개념 설명 전체 · v6.18.37 / net/core/dev.c
1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * NET3 Protocol independent device support routines. 4 * 5 * Derived from the non IP parts of dev.c 1.0.19 6 * Authors: Ross Biro 7 * Fred N. van Kempen, <[email protected]> 8 * Mark Evans, <[email protected]> 9 * 10 * Additional Authors: 11 * Florian la Roche <[email protected]> 12 * Alan Cox <[email protected]> 13 * David Hinds <[email protected]> 14 * Alexey Kuznetsov <[email protected]> 15 * Adam Sulmicki <[email protected]> 16 * Pekka Riikonen <[email protected]> 17 * 18 * Changes: 19 * D.J. Barrow : Fixed bug where dev->refcnt gets set 20 * to 2 if register_netdev gets called 21 * before net_dev_init & also removed a 22 * few lines of code in the process. 23 * Alan Cox : device private ioctl copies fields back. 24 * Alan Cox : Transmit queue code does relevant 25 * stunts to keep the queue safe. 26 * Alan Cox : Fixed double lock. 27 * Alan Cox : Fixed promisc NULL pointer trap 28 * ???????? : Support the full private ioctl range 29 * Alan Cox : Moved ioctl permission check into 30 * drivers 31 * Tim Kordas : SIOCADDMULTI/SIOCDELMULTI 32 * Alan Cox : 100 backlog just doesn't cut it when 33 * you start doing multicast video 8) 34 * Alan Cox : Rewrote net_bh and list manager. 35 * Alan Cox : Fix ETH_P_ALL echoback lengths. 36 * Alan Cox : Took out transmit every packet pass 37 * Saved a few bytes in the ioctl handler 38 * Alan Cox : Network driver sets packet type before 39 * calling netif_rx. Saves a function 40 * call a packet. 41 * Alan Cox : Hashed net_bh() 42 * Richard Kooijman: Timestamp fixes. 43 * Alan Cox : Wrong field in SIOCGIFDSTADDR 44 * Alan Cox : Device lock protection. 45 * Alan Cox : Fixed nasty side effect of device close 46 * changes. 47 * Rudi Cilibrasi : Pass the right thing to 48 * set_mac_address() 49 * Dave Miller : 32bit quantity for the device lock to 50 * make it work out on a Sparc. 51 * Bjorn Ekwall : Added KERNELD hack. 52 * Alan Cox : Cleaned up the backlog initialise. 53 * Craig Metz : SIOCGIFCONF fix if space for under 54 * 1 device. 55 * Thomas Bogendoerfer : Return ENODEV for dev_open, if there 56 * is no device open function. 57 * Andi Kleen : Fix error reporting for SIOCGIFCONF 58 * Michael Chastain : Fix signed/unsigned for SIOCGIFCONF 59 * Cyrus Durgin : Cleaned for KMOD 60 * Adam Sulmicki : Bug Fix : Network Device Unload 61 * A network device unload needs to purge 62 * the backlog queue. 63 * Paul Rusty Russell : SIOCSIFNAME 64 * Pekka Riikonen : Netdev boot-time settings code 65 * Andrew Morton : Make unregister_netdevice wait 66 * indefinitely on dev->refcnt 67 * J Hadi Salim : - Backlog queue sampling 68 * - netif_rx() feedback 69 */ 70 71 #include <linux/uaccess.h> 72 #include <linux/bitmap.h> 73 #include <linux/capability.h> 74 #include <linux/cpu.h> 75 #include <linux/types.h> 76 #include <linux/kernel.h> 77 #include <linux/hash.h> 78 #include <linux/slab.h> 79 #include <linux/sched.h> 80 #include <linux/sched/isolation.h> 81 #include <linux/sched/mm.h> 82 #include <linux/smpboot.h> 83 #include <linux/mutex.h> 84 #include <linux/rwsem.h> 85 #include <linux/string.h> 86 #include <linux/mm.h> 87 #include <linux/socket.h> 88 #include <linux/sockios.h> 89 #include <linux/errno.h> 90 #include <linux/interrupt.h> 91 #include <linux/if_ether.h> 92 #include <linux/netdevice.h> 93 #include <linux/etherdevice.h> 94 #include <linux/ethtool.h> 95 #include <linux/ethtool_netlink.h> 96 #include <linux/skbuff.h> 97 #include <linux/kthread.h> 98 #include <linux/bpf.h> 99 #include <linux/bpf_trace.h> 100 #include <net/net_namespace.h> 101 #include <net/sock.h> 102 #include <net/busy_poll.h> 103 #include <linux/rtnetlink.h> 104 #include <linux/stat.h> 105 #include <net/dsa.h> 106 #include <net/dst.h> 107 #include <net/dst_metadata.h> 108 #include <net/gro.h> 109 #include <net/netdev_queues.h> 110 #include <net/pkt_sched.h> 111 #include <net/pkt_cls.h> 112 #include <net/checksum.h> 113 #include <net/xfrm.h> 114 #include <net/tcx.h> 115 #include <linux/highmem.h> 116 #include <linux/init.h> 117 #include <linux/module.h> 118 #include <linux/netpoll.h> 119 #include <linux/rcupdate.h> 120 #include <linux/delay.h> 121 #include <net/iw_handler.h> 122 #include <asm/current.h> 123 #include <linux/audit.h> 124 #include <linux/dmaengine.h> 125 #include <linux/err.h> 126 #include <linux/ctype.h> 127 #include <linux/if_arp.h> 128 #include <linux/if_vlan.h> 129 #include <linux/ip.h> 130 #include <net/ip.h> 131 #include <net/mpls.h> 132 #include <linux/ipv6.h> 133 #include <linux/in.h> 134 #include <linux/jhash.h> 135 #include <linux/random.h> 136 #include <trace/events/napi.h> 137 #include <trace/events/net.h> 138 #include <trace/events/skb.h> 139 #include <trace/events/qdisc.h> 140 #include <trace/events/xdp.h> 141 #include <linux/inetdevice.h> 142 #include <linux/cpu_rmap.h> 143 #include <linux/static_key.h> 144 #include <linux/hashtable.h> 145 #include <linux/vmalloc.h> 146 #include <linux/if_macvlan.h> 147 #include <linux/errqueue.h> 148 #include <linux/hrtimer.h> 149 #include <linux/netfilter_netdev.h> 150 #include <linux/crash_dump.h> 151 #include <linux/sctp.h> 152 #include <net/udp_tunnel.h> 153 #include <linux/net_namespace.h> 154 #include <linux/indirect_call_wrapper.h> 155 #include <net/devlink.h> 156 #include <linux/pm_runtime.h> 157 #include <linux/prandom.h> 158 #include <linux/once_lite.h> 159 #include <net/netdev_lock.h> 160 #include <net/netdev_rx_queue.h> 161 #include <net/page_pool/types.h> 162 #include <net/page_pool/helpers.h> 163 #include <net/page_pool/memory_provider.h> 164 #include <net/rps.h> 165 #include <linux/phy_link_topology.h> 166 167 #include "dev.h" 168 #include "devmem.h" 169 #include "net-sysfs.h" 170 171 static DEFINE_SPINLOCK(ptype_lock); 172 struct list_head ptype_base[PTYPE_HASH_SIZE] __read_mostly; 173 174 static int netif_rx_internal(struct sk_buff *skb); 175 static int call_netdevice_notifiers_extack(unsigned long val, 176 struct net_device *dev, 177 struct netlink_ext_ack *extack); 178 179 static DEFINE_MUTEX(ifalias_mutex); 180 181 /* protects napi_hash addition/deletion and napi_gen_id */ 182 static DEFINE_SPINLOCK(napi_hash_lock); 183 184 static unsigned int napi_gen_id = NR_CPUS; 185 static DEFINE_READ_MOSTLY_HASHTABLE(napi_hash, 8); 186 187 static inline void dev_base_seq_inc(struct net *net) 188 { 189 unsigned int val = net->dev_base_seq + 1; 190 191 WRITE_ONCE(net->dev_base_seq, val ?: 1); 192 } 193 194 static inline struct hlist_head *dev_name_hash(struct net *net, const char *name) 195 { 196 unsigned int hash = full_name_hash(net, name, strnlen(name, IFNAMSIZ)); 197 198 return &net->dev_name_head[hash_32(hash, NETDEV_HASHBITS)]; 199 } 200 201 static inline struct hlist_head *dev_index_hash(struct net *net, int ifindex) 202 { 203 return &net->dev_index_head[ifindex & (NETDEV_HASHENTRIES - 1)]; 204 } 205 206 #ifndef CONFIG_PREEMPT_RT 207 208 static DEFINE_STATIC_KEY_FALSE(use_backlog_threads_key); 209 210 static int __init setup_backlog_napi_threads(char *arg) 211 { 212 static_branch_enable(&use_backlog_threads_key); 213 return 0; 214 } 215 early_param("thread_backlog_napi", setup_backlog_napi_threads); 216 217 static bool use_backlog_threads(void) 218 { 219 return static_branch_unlikely(&use_backlog_threads_key); 220 } 221 222 #else 223 224 static bool use_backlog_threads(void) 225 { 226 return true; 227 } 228 229 #endif 230 231 static inline void backlog_lock_irq_save(struct softnet_data *sd, 232 unsigned long *flags) 233 { 234 if (IS_ENABLED(CONFIG_RPS) || use_backlog_threads()) 235 spin_lock_irqsave(&sd->input_pkt_queue.lock, *flags); 236 else 237 local_irq_save(*flags); 238 } 239 240 static inline void backlog_lock_irq_disable(struct softnet_data *sd) 241 { 242 if (IS_ENABLED(CONFIG_RPS) || use_backlog_threads()) 243 spin_lock_irq(&sd->input_pkt_queue.lock); 244 else 245 local_irq_disable(); 246 } 247 248 static inline void backlog_unlock_irq_restore(struct softnet_data *sd, 249 unsigned long *flags) 250 { 251 if (IS_ENABLED(CONFIG_RPS) || use_backlog_threads()) 252 spin_unlock_irqrestore(&sd->input_pkt_queue.lock, *flags); 253 else 254 local_irq_restore(*flags); 255 } 256 257 static inline void backlog_unlock_irq_enable(struct softnet_data *sd) 258 { 259 if (IS_ENABLED(CONFIG_RPS) || use_backlog_threads()) 260 spin_unlock_irq(&sd->input_pkt_queue.lock); 261 else 262 local_irq_enable(); 263 } 264 265 static struct netdev_name_node *netdev_name_node_alloc(struct net_device *dev, 266 const char *name) 267 { 268 struct netdev_name_node *name_node; 269 270 name_node = kmalloc(sizeof(*name_node), GFP_KERNEL); 271 if (!name_node) 272 return NULL; 273 INIT_HLIST_NODE(&name_node->hlist); 274 name_node->dev = dev; 275 name_node->name = name; 276 return name_node; 277 } 278 279 static struct netdev_name_node * 280 netdev_name_node_head_alloc(struct net_device *dev) 281 { 282 struct netdev_name_node *name_node; 283 284 name_node = netdev_name_node_alloc(dev, dev->name); 285 if (!name_node) 286 return NULL; 287 INIT_LIST_HEAD(&name_node->list); 288 return name_node; 289 } 290 291 static void netdev_name_node_free(struct netdev_name_node *name_node) 292 { 293 kfree(name_node); 294 } 295 296 static void netdev_name_node_add(struct net *net, 297 struct netdev_name_node *name_node) 298 { 299 hlist_add_head_rcu(&name_node->hlist, 300 dev_name_hash(net, name_node->name)); 301 } 302 303 static void netdev_name_node_del(struct netdev_name_node *name_node) 304 { 305 hlist_del_rcu(&name_node->hlist); 306 } 307 308 static struct netdev_name_node *netdev_name_node_lookup(struct net *net, 309 const char *name) 310 { 311 struct hlist_head *head = dev_name_hash(net, name); 312 struct netdev_name_node *name_node; 313 314 hlist_for_each_entry(name_node, head, hlist) 315 if (!strcmp(name_node->name, name)) 316 return name_node; 317 return NULL; 318 } 319 320 static struct netdev_name_node *netdev_name_node_lookup_rcu(struct net *net, 321 const char *name) 322 { 323 struct hlist_head *head = dev_name_hash(net, name); 324 struct netdev_name_node *name_node; 325 326 hlist_for_each_entry_rcu(name_node, head, hlist) 327 if (!strcmp(name_node->name, name)) 328 return name_node; 329 return NULL; 330 } 331 332 bool netdev_name_in_use(struct net *net, const char *name) 333 { 334 return netdev_name_node_lookup(net, name); 335 } 336 EXPORT_SYMBOL(netdev_name_in_use); 337 338 int netdev_name_node_alt_create(struct net_device *dev, const char *name) 339 { 340 struct netdev_name_node *name_node; 341 struct net *net = dev_net(dev); 342 343 name_node = netdev_name_node_lookup(net, name); 344 if (name_node) 345 return -EEXIST; 346 name_node = netdev_name_node_alloc(dev, name); 347 if (!name_node) 348 return -ENOMEM; 349 netdev_name_node_add(net, name_node); 350 /* The node that holds dev->name acts as a head of per-device list. */ 351 list_add_tail_rcu(&name_node->list, &dev->name_node->list); 352 353 return 0; 354 } 355 356 static void netdev_name_node_alt_free(struct rcu_head *head) 357 { 358 struct netdev_name_node *name_node = 359 container_of(head, struct netdev_name_node, rcu); 360 361 kfree(name_node->name); 362 netdev_name_node_free(name_node); 363 } 364 365 static void __netdev_name_node_alt_destroy(struct netdev_name_node *name_node) 366 { 367 netdev_name_node_del(name_node); 368 list_del(&name_node->list); 369 call_rcu(&name_node->rcu, netdev_name_node_alt_free); 370 } 371 372 int netdev_name_node_alt_destroy(struct net_device *dev, const char *name) 373 { 374 struct netdev_name_node *name_node; 375 struct net *net = dev_net(dev); 376 377 name_node = netdev_name_node_lookup(net, name); 378 if (!name_node) 379 return -ENOENT; 380 /* lookup might have found our primary name or a name belonging 381 * to another device. 382 */ 383 if (name_node == dev->name_node || name_node->dev != dev) 384 return -EINVAL; 385 386 __netdev_name_node_alt_destroy(name_node); 387 return 0; 388 } 389 390 static void netdev_name_node_alt_flush(struct net_device *dev) 391 { 392 struct netdev_name_node *name_node, *tmp; 393 394 list_for_each_entry_safe(name_node, tmp, &dev->name_node->list, list) { 395 list_del(&name_node->list); 396 netdev_name_node_alt_free(&name_node->rcu); 397 } 398 } 399 400 /* Device list insertion */ 401 static void list_netdevice(struct net_device *dev) 402 { 403 struct netdev_name_node *name_node; 404 struct net *net = dev_net(dev); 405 406 ASSERT_RTNL(); 407 408 list_add_tail_rcu(&dev->dev_list, &net->dev_base_head); 409 netdev_name_node_add(net, dev->name_node); 410 hlist_add_head_rcu(&dev->index_hlist, 411 dev_index_hash(net, dev->ifindex)); 412 413 netdev_for_each_altname(dev, name_node) 414 netdev_name_node_add(net, name_node); 415 416 /* We reserved the ifindex, this can't fail */ 417 WARN_ON(xa_store(&net->dev_by_index, dev->ifindex, dev, GFP_KERNEL)); 418 419 dev_base_seq_inc(net); 420 } 421 422 /* Device list removal 423 * caller must respect a RCU grace period before freeing/reusing dev 424 */ 425 static void unlist_netdevice(struct net_device *dev) 426 { 427 struct netdev_name_node *name_node; 428 struct net *net = dev_net(dev); 429 430 ASSERT_RTNL(); 431 432 xa_erase(&net->dev_by_index, dev->ifindex); 433 434 netdev_for_each_altname(dev, name_node) 435 netdev_name_node_del(name_node); 436 437 /* Unlink dev from the device chain */ 438 list_del_rcu(&dev->dev_list); 439 netdev_name_node_del(dev->name_node); 440 hlist_del_rcu(&dev->index_hlist); 441 442 dev_base_seq_inc(dev_net(dev)); 443 } 444 445 /* 446 * Our notifier list 447 */ 448 449 static RAW_NOTIFIER_HEAD(netdev_chain); 450 451 /* 452 * Device drivers call our routines to queue packets here. We empty the 453 * queue in the local softnet handler. 454 */ 455 456 DEFINE_PER_CPU_ALIGNED(struct softnet_data, softnet_data) = { 457 .process_queue_bh_lock = INIT_LOCAL_LOCK(process_queue_bh_lock), 458 }; 459 EXPORT_PER_CPU_SYMBOL(softnet_data); 460 461 /* Page_pool has a lockless array/stack to alloc/recycle pages. 462 * PP consumers must pay attention to run APIs in the appropriate context 463 * (e.g. NAPI context). 464 */ 465 DEFINE_PER_CPU(struct page_pool_bh, system_page_pool) = { 466 .bh_lock = INIT_LOCAL_LOCK(bh_lock), 467 }; 468 469 #ifdef CONFIG_LOCKDEP 470 /* 471 * register_netdevice() inits txq->_xmit_lock and sets lockdep class 472 * according to dev->type 473 */ 474 static const unsigned short netdev_lock_type[] = { 475 ARPHRD_NETROM, ARPHRD_ETHER, ARPHRD_EETHER, ARPHRD_AX25, 476 ARPHRD_PRONET, ARPHRD_CHAOS, ARPHRD_IEEE802, ARPHRD_ARCNET, 477 ARPHRD_APPLETLK, ARPHRD_DLCI, ARPHRD_ATM, ARPHRD_METRICOM, 478 ARPHRD_IEEE1394, ARPHRD_EUI64, ARPHRD_INFINIBAND, ARPHRD_SLIP, 479 ARPHRD_CSLIP, ARPHRD_SLIP6, ARPHRD_CSLIP6, ARPHRD_RSRVD, 480 ARPHRD_ADAPT, ARPHRD_ROSE, ARPHRD_X25, ARPHRD_HWX25, 481 ARPHRD_CAN, ARPHRD_MCTP, 482 ARPHRD_PPP, ARPHRD_CISCO, ARPHRD_LAPB, ARPHRD_DDCMP, 483 ARPHRD_RAWHDLC, ARPHRD_RAWIP, 484 ARPHRD_TUNNEL, ARPHRD_TUNNEL6, ARPHRD_FRAD, 485 ARPHRD_SKIP, ARPHRD_LOOPBACK, ARPHRD_LOCALTLK, ARPHRD_FDDI, 486 ARPHRD_BIF, ARPHRD_SIT, ARPHRD_IPDDP, ARPHRD_IPGRE, 487 ARPHRD_PIMREG, ARPHRD_HIPPI, ARPHRD_ASH, ARPHRD_ECONET, 488 ARPHRD_IRDA, ARPHRD_FCPP, ARPHRD_FCAL, ARPHRD_FCPL, 489 ARPHRD_FCFABRIC, ARPHRD_IEEE80211, ARPHRD_IEEE80211_PRISM, 490 ARPHRD_IEEE80211_RADIOTAP, 491 ARPHRD_IEEE802154, ARPHRD_IEEE802154_MONITOR, 492 ARPHRD_PHONET, ARPHRD_PHONET_PIPE, 493 ARPHRD_CAIF, ARPHRD_IP6GRE, ARPHRD_NETLINK, ARPHRD_6LOWPAN, 494 ARPHRD_VSOCKMON, 495 ARPHRD_VOID, ARPHRD_NONE}; 496 497 static const char *const netdev_lock_name[] = { 498 "_xmit_NETROM", "_xmit_ETHER", "_xmit_EETHER", "_xmit_AX25", 499 "_xmit_PRONET", "_xmit_CHAOS", "_xmit_IEEE802", "_xmit_ARCNET", 500 "_xmit_APPLETLK", "_xmit_DLCI", "_xmit_ATM", "_xmit_METRICOM", 501 "_xmit_IEEE1394", "_xmit_EUI64", "_xmit_INFINIBAND", "_xmit_SLIP", 502 "_xmit_CSLIP", "_xmit_SLIP6", "_xmit_CSLIP6", "_xmit_RSRVD", 503 "_xmit_ADAPT", "_xmit_ROSE", "_xmit_X25", "_xmit_HWX25", 504 "_xmit_CAN", "_xmit_MCTP", 505 "_xmit_PPP", "_xmit_CISCO", "_xmit_LAPB", "_xmit_DDCMP", 506 "_xmit_RAWHDLC", "_xmit_RAWIP", 507 "_xmit_TUNNEL", "_xmit_TUNNEL6", "_xmit_FRAD", 508 "_xmit_SKIP", "_xmit_LOOPBACK", "_xmit_LOCALTLK", "_xmit_FDDI", 509 "_xmit_BIF", "_xmit_SIT", "_xmit_IPDDP", "_xmit_IPGRE", 510 "_xmit_PIMREG", "_xmit_HIPPI", "_xmit_ASH", "_xmit_ECONET", 511 "_xmit_IRDA", "_xmit_FCPP", "_xmit_FCAL", "_xmit_FCPL", 512 "_xmit_FCFABRIC", "_xmit_IEEE80211", "_xmit_IEEE80211_PRISM", 513 "_xmit_IEEE80211_RADIOTAP", 514 "_xmit_IEEE802154", "_xmit_IEEE802154_MONITOR", 515 "_xmit_PHONET", "_xmit_PHONET_PIPE", 516 "_xmit_CAIF", "_xmit_IP6GRE", "_xmit_NETLINK", "_xmit_6LOWPAN", 517 "_xmit_VSOCKMON", 518 "_xmit_VOID", "_xmit_NONE"}; 519 520 static struct lock_class_key netdev_xmit_lock_key[ARRAY_SIZE(netdev_lock_type)]; 521 static struct lock_class_key netdev_addr_lock_key[ARRAY_SIZE(netdev_lock_type)]; 522 523 static inline unsigned short netdev_lock_pos(unsigned short dev_type) 524 { 525 int i; 526 527 for (i = 0; i < ARRAY_SIZE(netdev_lock_type); i++) 528 if (netdev_lock_type[i] == dev_type) 529 return i; 530 /* the last key is used by default */ 531 WARN_ONCE(1, "netdev_lock_pos() could not find dev_type=%u\n", dev_type); 532 return ARRAY_SIZE(netdev_lock_type) - 1; 533 } 534 535 static inline void netdev_set_xmit_lockdep_class(spinlock_t *lock, 536 unsigned short dev_type) 537 { 538 int i; 539 540 i = netdev_lock_pos(dev_type); 541 lockdep_set_class_and_name(lock, &netdev_xmit_lock_key[i], 542 netdev_lock_name[i]); 543 } 544 545 static inline void netdev_set_addr_lockdep_class(struct net_device *dev) 546 { 547 int i; 548 549 i = netdev_lock_pos(dev->type); 550 lockdep_set_class_and_name(&dev->addr_list_lock, 551 &netdev_addr_lock_key[i], 552 netdev_lock_name[i]); 553 } 554 #else 555 static inline void netdev_set_xmit_lockdep_class(spinlock_t *lock, 556 unsigned short dev_type) 557 { 558 } 559 560 static inline void netdev_set_addr_lockdep_class(struct net_device *dev) 561 { 562 } 563 #endif 564 565 /******************************************************************************* 566 * 567 * Protocol management and registration routines 568 * 569 *******************************************************************************/ 570 571 572 /* 573 * Add a protocol ID to the list. Now that the input handler is 574 * smarter we can dispense with all the messy stuff that used to be 575 * here. 576 * 577 * BEWARE!!! Protocol handlers, mangling input packets, 578 * MUST BE last in hash buckets and checking protocol handlers 579 * MUST start from promiscuous ptype_all chain in net_bh. 580 * It is true now, do not change it. 581 * Explanation follows: if protocol handler, mangling packet, will 582 * be the first on list, it is not able to sense, that packet 583 * is cloned and should be copied-on-write, so that it will 584 * change it and subsequent readers will get broken packet. 585 * --ANK (980803) 586 */ 587 588 static inline struct list_head *ptype_head(const struct packet_type *pt) 589 { 590 if (pt->type == htons(ETH_P_ALL)) { 591 if (!pt->af_packet_net && !pt->dev) 592 return NULL; 593 594 return pt->dev ? &pt->dev->ptype_all : 595 &pt->af_packet_net->ptype_all; 596 } 597 598 if (pt->dev) 599 return &pt->dev->ptype_specific; 600 601 return pt->af_packet_net ? &pt->af_packet_net->ptype_specific : 602 &ptype_base[ntohs(pt->type) & PTYPE_HASH_MASK]; 603 } 604 605 /** 606 * dev_add_pack - add packet handler 607 * @pt: packet type declaration 608 * 609 * Add a protocol handler to the networking stack. The passed &packet_type 610 * is linked into kernel lists and may not be freed until it has been 611 * removed from the kernel lists. 612 * 613 * This call does not sleep therefore it can not 614 * guarantee all CPU's that are in middle of receiving packets 615 * will see the new packet type (until the next received packet). 616 */ 617 618 void dev_add_pack(struct packet_type *pt) 619 { 620 struct list_head *head = ptype_head(pt); 621 622 if (WARN_ON_ONCE(!head)) 623 return; 624 625 spin_lock(&ptype_lock); 626 list_add_rcu(&pt->list, head); 627 spin_unlock(&ptype_lock); 628 } 629 EXPORT_SYMBOL(dev_add_pack); 630 631 /** 632 * __dev_remove_pack - remove packet handler 633 * @pt: packet type declaration 634 * 635 * Remove a protocol handler that was previously added to the kernel 636 * protocol handlers by dev_add_pack(). The passed &packet_type is removed 637 * from the kernel lists and can be freed or reused once this function 638 * returns. 639 * 640 * The packet type might still be in use by receivers 641 * and must not be freed until after all the CPU's have gone 642 * through a quiescent state. 643 */ 644 void __dev_remove_pack(struct packet_type *pt) 645 { 646 struct list_head *head = ptype_head(pt); 647 struct packet_type *pt1; 648 649 if (!head) 650 return; 651 652 spin_lock(&ptype_lock); 653 654 list_for_each_entry(pt1, head, list) { 655 if (pt == pt1) { 656 list_del_rcu(&pt->list); 657 goto out; 658 } 659 } 660 661 pr_warn("dev_remove_pack: %p not found\n", pt); 662 out: 663 spin_unlock(&ptype_lock); 664 } 665 EXPORT_SYMBOL(__dev_remove_pack); 666 667 /** 668 * dev_remove_pack - remove packet handler 669 * @pt: packet type declaration 670 * 671 * Remove a protocol handler that was previously added to the kernel 672 * protocol handlers by dev_add_pack(). The passed &packet_type is removed 673 * from the kernel lists and can be freed or reused once this function 674 * returns. 675 * 676 * This call sleeps to guarantee that no CPU is looking at the packet 677 * type after return. 678 */ 679 void dev_remove_pack(struct packet_type *pt) 680 { 681 __dev_remove_pack(pt); 682 683 synchronize_net(); 684 } 685 EXPORT_SYMBOL(dev_remove_pack); 686 687 688 /******************************************************************************* 689 * 690 * Device Interface Subroutines 691 * 692 *******************************************************************************/ 693 694 /** 695 * dev_get_iflink - get 'iflink' value of a interface 696 * @dev: targeted interface 697 * 698 * Indicates the ifindex the interface is linked to. 699 * Physical interfaces have the same 'ifindex' and 'iflink' values. 700 */ 701 702 int dev_get_iflink(const struct net_device *dev) 703 { 704 if (dev->netdev_ops && dev->netdev_ops->ndo_get_iflink) 705 return dev->netdev_ops->ndo_get_iflink(dev); 706 707 return READ_ONCE(dev->ifindex); 708 } 709 EXPORT_SYMBOL(dev_get_iflink); 710 711 /** 712 * dev_fill_metadata_dst - Retrieve tunnel egress information. 713 * @dev: targeted interface 714 * @skb: The packet. 715 * 716 * For better visibility of tunnel traffic OVS needs to retrieve 717 * egress tunnel information for a packet. Following API allows 718 * user to get this info. 719 */ 720 int dev_fill_metadata_dst(struct net_device *dev, struct sk_buff *skb) 721 { 722 struct ip_tunnel_info *info; 723 724 if (!dev->netdev_ops || !dev->netdev_ops->ndo_fill_metadata_dst) 725 return -EINVAL; 726 727 info = skb_tunnel_info_unclone(skb); 728 if (!info) 729 return -ENOMEM; 730 if (unlikely(!(info->mode & IP_TUNNEL_INFO_TX))) 731 return -EINVAL; 732 733 return dev->netdev_ops->ndo_fill_metadata_dst(dev, skb); 734 } 735 EXPORT_SYMBOL_GPL(dev_fill_metadata_dst); 736 737 static struct net_device_path *dev_fwd_path(struct net_device_path_stack *stack) 738 { 739 int k = stack->num_paths++; 740 741 if (k >= NET_DEVICE_PATH_STACK_MAX) 742 return NULL; 743 744 return &stack->path[k]; 745 } 746 747 int dev_fill_forward_path(const struct net_device *dev, const u8 *daddr, 748 struct net_device_path_stack *stack) 749 { 750 const struct net_device *last_dev; 751 struct net_device_path_ctx ctx = { 752 .dev = dev, 753 }; 754 struct net_device_path *path; 755 int ret = 0; 756 757 memcpy(ctx.daddr, daddr, sizeof(ctx.daddr)); 758 stack->num_paths = 0; 759 while (ctx.dev && ctx.dev->netdev_ops->ndo_fill_forward_path) { 760 last_dev = ctx.dev; 761 path = dev_fwd_path(stack); 762 if (!path) 763 return -1; 764 765 memset(path, 0, sizeof(struct net_device_path)); 766 ret = ctx.dev->netdev_ops->ndo_fill_forward_path(&ctx, path); 767 if (ret < 0) 768 return -1; 769 770 if (WARN_ON_ONCE(last_dev == ctx.dev)) 771 return -1; 772 } 773 774 if (!ctx.dev) 775 return ret; 776 777 path = dev_fwd_path(stack); 778 if (!path) 779 return -1; 780 path->type = DEV_PATH_ETHERNET; 781 path->dev = ctx.dev; 782 783 return ret; 784 } 785 EXPORT_SYMBOL_GPL(dev_fill_forward_path); 786 787 /* must be called under rcu_read_lock(), as we dont take a reference */ 788 static struct napi_struct *napi_by_id(unsigned int napi_id) 789 { 790 unsigned int hash = napi_id % HASH_SIZE(napi_hash); 791 struct napi_struct *napi; 792 793 hlist_for_each_entry_rcu(napi, &napi_hash[hash], napi_hash_node) 794 if (napi->napi_id == napi_id) 795 return napi; 796 797 return NULL; 798 } 799 800 /* must be called under rcu_read_lock(), as we dont take a reference */ 801 static struct napi_struct * 802 netdev_napi_by_id(struct net *net, unsigned int napi_id) 803 { 804 struct napi_struct *napi; 805 806 napi = napi_by_id(napi_id); 807 if (!napi) 808 return NULL; 809 810 if (WARN_ON_ONCE(!napi->dev)) 811 return NULL; 812 if (!net_eq(net, dev_net(napi->dev))) 813 return NULL; 814 815 return napi; 816 } 817 818 /** 819 * netdev_napi_by_id_lock() - find a device by NAPI ID and lock it 820 * @net: the applicable net namespace 821 * @napi_id: ID of a NAPI of a target device 822 * 823 * Find a NAPI instance with @napi_id. Lock its device. 824 * The device must be in %NETREG_REGISTERED state for lookup to succeed. 825 * netdev_unlock() must be called to release it. 826 * 827 * Return: pointer to NAPI, its device with lock held, NULL if not found. 828 */ 829 struct napi_struct * 830 netdev_napi_by_id_lock(struct net *net, unsigned int napi_id) 831 { 832 struct napi_struct *napi; 833 struct net_device *dev; 834 835 rcu_read_lock(); 836 napi = netdev_napi_by_id(net, napi_id); 837 if (!napi || READ_ONCE(napi->dev->reg_state) != NETREG_REGISTERED) { 838 rcu_read_unlock(); 839 return NULL; 840 } 841 842 dev = napi->dev; 843 dev_hold(dev); 844 rcu_read_unlock(); 845 846 dev = __netdev_put_lock(dev, net); 847 if (!dev) 848 return NULL; 849 850 rcu_read_lock(); 851 napi = netdev_napi_by_id(net, napi_id); 852 if (napi && napi->dev != dev) 853 napi = NULL; 854 rcu_read_unlock(); 855 856 if (!napi) 857 netdev_unlock(dev); 858 return napi; 859 } 860 861 /** 862 * __dev_get_by_name - find a device by its name 863 * @net: the applicable net namespace 864 * @name: name to find 865 * 866 * Find an interface by name. Must be called under RTNL semaphore. 867 * If the name is found a pointer to the device is returned. 868 * If the name is not found then %NULL is returned. The 869 * reference counters are not incremented so the caller must be 870 * careful with locks. 871 */ 872 873 struct net_device *__dev_get_by_name(struct net *net, const char *name) 874 { 875 struct netdev_name_node *node_name; 876 877 node_name = netdev_name_node_lookup(net, name); 878 return node_name ? node_name->dev : NULL; 879 } 880 EXPORT_SYMBOL(__dev_get_by_name); 881 882 /** 883 * dev_get_by_name_rcu - find a device by its name 884 * @net: the applicable net namespace 885 * @name: name to find 886 * 887 * Find an interface by name. 888 * If the name is found a pointer to the device is returned. 889 * If the name is not found then %NULL is returned. 890 * The reference counters are not incremented so the caller must be 891 * careful with locks. The caller must hold RCU lock. 892 */ 893 894 struct net_device *dev_get_by_name_rcu(struct net *net, const char *name) 895 { 896 struct netdev_name_node *node_name; 897 898 node_name = netdev_name_node_lookup_rcu(net, name); 899 return node_name ? node_name->dev : NULL; 900 } 901 EXPORT_SYMBOL(dev_get_by_name_rcu); 902 903 /* Deprecated for new users, call netdev_get_by_name() instead */ 904 struct net_device *dev_get_by_name(struct net *net, const char *name) 905 { 906 struct net_device *dev; 907 908 rcu_read_lock(); 909 dev = dev_get_by_name_rcu(net, name); 910 dev_hold(dev); 911 rcu_read_unlock(); 912 return dev; 913 } 914 EXPORT_SYMBOL(dev_get_by_name); 915 916 /** 917 * netdev_get_by_name() - find a device by its name 918 * @net: the applicable net namespace 919 * @name: name to find 920 * @tracker: tracking object for the acquired reference 921 * @gfp: allocation flags for the tracker 922 * 923 * Find an interface by name. This can be called from any 924 * context and does its own locking. The returned handle has 925 * the usage count incremented and the caller must use netdev_put() to 926 * release it when it is no longer needed. %NULL is returned if no 927 * matching device is found. 928 */ 929 struct net_device *netdev_get_by_name(struct net *net, const char *name, 930 netdevice_tracker *tracker, gfp_t gfp) 931 { 932 struct net_device *dev; 933 934 dev = dev_get_by_name(net, name); 935 if (dev) 936 netdev_tracker_alloc(dev, tracker, gfp); 937 return dev; 938 } 939 EXPORT_SYMBOL(netdev_get_by_name); 940 941 /** 942 * __dev_get_by_index - find a device by its ifindex 943 * @net: the applicable net namespace 944 * @ifindex: index of device 945 * 946 * Search for an interface by index. Returns %NULL if the device 947 * is not found or a pointer to the device. The device has not 948 * had its reference counter increased so the caller must be careful 949 * about locking. The caller must hold the RTNL semaphore. 950 */ 951 952 struct net_device *__dev_get_by_index(struct net *net, int ifindex) 953 { 954 struct net_device *dev; 955 struct hlist_head *head = dev_index_hash(net, ifindex); 956 957 hlist_for_each_entry(dev, head, index_hlist) 958 if (dev->ifindex == ifindex) 959 return dev; 960 961 return NULL; 962 } 963 EXPORT_SYMBOL(__dev_get_by_index); 964 965 /** 966 * dev_get_by_index_rcu - find a device by its ifindex 967 * @net: the applicable net namespace 968 * @ifindex: index of device 969 * 970 * Search for an interface by index. Returns %NULL if the device 971 * is not found or a pointer to the device. The device has not 972 * had its reference counter increased so the caller must be careful 973 * about locking. The caller must hold RCU lock. 974 */ 975 976 struct net_device *dev_get_by_index_rcu(struct net *net, int ifindex) 977 { 978 struct net_device *dev; 979 struct hlist_head *head = dev_index_hash(net, ifindex); 980 981 hlist_for_each_entry_rcu(dev, head, index_hlist) 982 if (dev->ifindex == ifindex) 983 return dev; 984 985 return NULL; 986 } 987 EXPORT_SYMBOL(dev_get_by_index_rcu); 988 989 /* Deprecated for new users, call netdev_get_by_index() instead */ 990 struct net_device *dev_get_by_index(struct net *net, int ifindex) 991 { 992 struct net_device *dev; 993 994 rcu_read_lock(); 995 dev = dev_get_by_index_rcu(net, ifindex); 996 dev_hold(dev); 997 rcu_read_unlock(); 998 return dev; 999 } 1000 EXPORT_SYMBOL(dev_get_by_index); 1001 1002 /** 1003 * netdev_get_by_index() - find a device by its ifindex 1004 * @net: the applicable net namespace 1005 * @ifindex: index of device 1006 * @tracker: tracking object for the acquired reference 1007 * @gfp: allocation flags for the tracker 1008 * 1009 * Search for an interface by index. Returns NULL if the device 1010 * is not found or a pointer to the device. The device returned has 1011 * had a reference added and the pointer is safe until the user calls 1012 * netdev_put() to indicate they have finished with it. 1013 */ 1014 struct net_device *netdev_get_by_index(struct net *net, int ifindex, 1015 netdevice_tracker *tracker, gfp_t gfp) 1016 { 1017 struct net_device *dev; 1018 1019 dev = dev_get_by_index(net, ifindex); 1020 if (dev) 1021 netdev_tracker_alloc(dev, tracker, gfp); 1022 return dev; 1023 } 1024 EXPORT_SYMBOL(netdev_get_by_index); 1025 1026 /** 1027 * dev_get_by_napi_id - find a device by napi_id 1028 * @napi_id: ID of the NAPI struct 1029 * 1030 * Search for an interface by NAPI ID. Returns %NULL if the device 1031 * is not found or a pointer to the device. The device has not had 1032 * its reference counter increased so the caller must be careful 1033 * about locking. The caller must hold RCU lock. 1034 */ 1035 struct net_device *dev_get_by_napi_id(unsigned int napi_id) 1036 { 1037 struct napi_struct *napi; 1038 1039 WARN_ON_ONCE(!rcu_read_lock_held()); 1040 1041 if (!napi_id_valid(napi_id)) 1042 return NULL; 1043 1044 napi = napi_by_id(napi_id); 1045 1046 return napi ? napi->dev : NULL; 1047 } 1048 1049 /* Release the held reference on the net_device, and if the net_device 1050 * is still registered try to lock the instance lock. If device is being 1051 * unregistered NULL will be returned (but the reference has been released, 1052 * either way!) 1053 * 1054 * This helper is intended for locking net_device after it has been looked up 1055 * using a lockless lookup helper. Lock prevents the instance from going away. 1056 */ 1057 struct net_device *__netdev_put_lock(struct net_device *dev, struct net *net) 1058 { 1059 netdev_lock(dev); 1060 if (dev->reg_state > NETREG_REGISTERED || 1061 dev->moving_ns || !net_eq(dev_net(dev), net)) { 1062 netdev_unlock(dev); 1063 dev_put(dev); 1064 return NULL; 1065 } 1066 dev_put(dev); 1067 return dev; 1068 } 1069 1070 static struct net_device * 1071 __netdev_put_lock_ops_compat(struct net_device *dev, struct net *net) 1072 { 1073 netdev_lock_ops_compat(dev); 1074 if (dev->reg_state > NETREG_REGISTERED || 1075 dev->moving_ns || !net_eq(dev_net(dev), net)) { 1076 netdev_unlock_ops_compat(dev); 1077 dev_put(dev); 1078 return NULL; 1079 } 1080 dev_put(dev); 1081 return dev; 1082 } 1083 1084 /** 1085 * netdev_get_by_index_lock() - find a device by its ifindex 1086 * @net: the applicable net namespace 1087 * @ifindex: index of device 1088 * 1089 * Search for an interface by index. If a valid device 1090 * with @ifindex is found it will be returned with netdev->lock held. 1091 * netdev_unlock() must be called to release it. 1092 * 1093 * Return: pointer to a device with lock held, NULL if not found. 1094 */ 1095 struct net_device *netdev_get_by_index_lock(struct net *net, int ifindex) 1096 { 1097 struct net_device *dev; 1098 1099 dev = dev_get_by_index(net, ifindex); 1100 if (!dev) 1101 return NULL; 1102 1103 return __netdev_put_lock(dev, net); 1104 } 1105 1106 struct net_device * 1107 netdev_get_by_index_lock_ops_compat(struct net *net, int ifindex) 1108 { 1109 struct net_device *dev; 1110 1111 dev = dev_get_by_index(net, ifindex); 1112 if (!dev) 1113 return NULL; 1114 1115 return __netdev_put_lock_ops_compat(dev, net); 1116 } 1117 1118 struct net_device * 1119 netdev_xa_find_lock(struct net *net, struct net_device *dev, 1120 unsigned long *index) 1121 { 1122 if (dev) 1123 netdev_unlock(dev); 1124 1125 do { 1126 rcu_read_lock(); 1127 dev = xa_find(&net->dev_by_index, index, ULONG_MAX, XA_PRESENT); 1128 if (!dev) { 1129 rcu_read_unlock(); 1130 return NULL; 1131 } 1132 dev_hold(dev); 1133 rcu_read_unlock(); 1134 1135 dev = __netdev_put_lock(dev, net); 1136 if (dev) 1137 return dev; 1138 1139 (*index)++; 1140 } while (true); 1141 } 1142 1143 struct net_device * 1144 netdev_xa_find_lock_ops_compat(struct net *net, struct net_device *dev, 1145 unsigned long *index) 1146 { 1147 if (dev) 1148 netdev_unlock_ops_compat(dev); 1149 1150 do { 1151 rcu_read_lock(); 1152 dev = xa_find(&net->dev_by_index, index, ULONG_MAX, XA_PRESENT); 1153 if (!dev) { 1154 rcu_read_unlock(); 1155 return NULL; 1156 } 1157 dev_hold(dev); 1158 rcu_read_unlock(); 1159 1160 dev = __netdev_put_lock_ops_compat(dev, net); 1161 if (dev) 1162 return dev; 1163 1164 (*index)++; 1165 } while (true); 1166 } 1167 1168 static DEFINE_SEQLOCK(netdev_rename_lock); 1169 1170 void netdev_copy_name(struct net_device *dev, char *name) 1171 { 1172 unsigned int seq; 1173 1174 do { 1175 seq = read_seqbegin(&netdev_rename_lock); 1176 strscpy(name, dev->name, IFNAMSIZ); 1177 } while (read_seqretry(&netdev_rename_lock, seq)); 1178 } 1179 1180 /** 1181 * netdev_get_name - get a netdevice name, knowing its ifindex. 1182 * @net: network namespace 1183 * @name: a pointer to the buffer where the name will be stored. 1184 * @ifindex: the ifindex of the interface to get the name from. 1185 */ 1186 int netdev_get_name(struct net *net, char *name, int ifindex) 1187 { 1188 struct net_device *dev; 1189 int ret; 1190 1191 rcu_read_lock(); 1192 1193 dev = dev_get_by_index_rcu(net, ifindex); 1194 if (!dev) { 1195 ret = -ENODEV; 1196 goto out; 1197 } 1198 1199 netdev_copy_name(dev, name); 1200 1201 ret = 0; 1202 out: 1203 rcu_read_unlock(); 1204 return ret; 1205 } 1206 1207 static bool dev_addr_cmp(struct net_device *dev, unsigned short type, 1208 const char *ha) 1209 { 1210 return dev->type == type && !memcmp(dev->dev_addr, ha, dev->addr_len); 1211 } 1212 1213 /** 1214 * dev_getbyhwaddr_rcu - find a device by its hardware address 1215 * @net: the applicable net namespace 1216 * @type: media type of device 1217 * @ha: hardware address 1218 * 1219 * Search for an interface by MAC address. Returns NULL if the device 1220 * is not found or a pointer to the device. 1221 * The caller must hold RCU. 1222 * The returned device has not had its ref count increased 1223 * and the caller must therefore be careful about locking 1224 * 1225 */ 1226 1227 struct net_device *dev_getbyhwaddr_rcu(struct net *net, unsigned short type, 1228 const char *ha) 1229 { 1230 struct net_device *dev; 1231 1232 for_each_netdev_rcu(net, dev) 1233 if (dev_addr_cmp(dev, type, ha)) 1234 return dev; 1235 1236 return NULL; 1237 } 1238 EXPORT_SYMBOL(dev_getbyhwaddr_rcu); 1239 1240 /** 1241 * dev_getbyhwaddr() - find a device by its hardware address 1242 * @net: the applicable net namespace 1243 * @type: media type of device 1244 * @ha: hardware address 1245 * 1246 * Similar to dev_getbyhwaddr_rcu(), but the owner needs to hold 1247 * rtnl_lock. 1248 * 1249 * Context: rtnl_lock() must be held. 1250 * Return: pointer to the net_device, or NULL if not found 1251 */ 1252 struct net_device *dev_getbyhwaddr(struct net *net, unsigned short type, 1253 const char *ha) 1254 { 1255 struct net_device *dev; 1256 1257 ASSERT_RTNL(); 1258 for_each_netdev(net, dev) 1259 if (dev_addr_cmp(dev, type, ha)) 1260 return dev; 1261 1262 return NULL; 1263 } 1264 EXPORT_SYMBOL(dev_getbyhwaddr); 1265 1266 struct net_device *dev_getfirstbyhwtype(struct net *net, unsigned short type) 1267 { 1268 struct net_device *dev, *ret = NULL; 1269 1270 rcu_read_lock(); 1271 for_each_netdev_rcu(net, dev) 1272 if (dev->type == type) { 1273 dev_hold(dev); 1274 ret = dev; 1275 break; 1276 } 1277 rcu_read_unlock(); 1278 return ret; 1279 } 1280 EXPORT_SYMBOL(dev_getfirstbyhwtype); 1281 1282 /** 1283 * netdev_get_by_flags_rcu - find any device with given flags 1284 * @net: the applicable net namespace 1285 * @tracker: tracking object for the acquired reference 1286 * @if_flags: IFF_* values 1287 * @mask: bitmask of bits in if_flags to check 1288 * 1289 * Search for any interface with the given flags. 1290 * 1291 * Context: rcu_read_lock() must be held. 1292 * Returns: NULL if a device is not found or a pointer to the device. 1293 */ 1294 struct net_device *netdev_get_by_flags_rcu(struct net *net, netdevice_tracker *tracker, 1295 unsigned short if_flags, unsigned short mask) 1296 { 1297 struct net_device *dev; 1298 1299 for_each_netdev_rcu(net, dev) { 1300 if (((READ_ONCE(dev->flags) ^ if_flags) & mask) == 0) { 1301 netdev_hold(dev, tracker, GFP_ATOMIC); 1302 return dev; 1303 } 1304 } 1305 1306 return NULL; 1307 } 1308 EXPORT_IPV6_MOD(netdev_get_by_flags_rcu); 1309 1310 /** 1311 * dev_valid_name - check if name is okay for network device 1312 * @name: name string 1313 * 1314 * Network device names need to be valid file names to 1315 * allow sysfs to work. We also disallow any kind of 1316 * whitespace. 1317 */ 1318 bool dev_valid_name(const char *name) 1319 { 1320 if (*name == '\0') 1321 return false; 1322 if (strnlen(name, IFNAMSIZ) == IFNAMSIZ) 1323 return false; 1324 if (!strcmp(name, ".") || !strcmp(name, "..")) 1325 return false; 1326 1327 while (*name) { 1328 if (*name == '/' || *name == ':' || isspace(*name)) 1329 return false; 1330 name++; 1331 } 1332 return true; 1333 } 1334 EXPORT_SYMBOL(dev_valid_name); 1335 1336 /** 1337 * __dev_alloc_name - allocate a name for a device 1338 * @net: network namespace to allocate the device name in 1339 * @name: name format string 1340 * @res: result name string 1341 * 1342 * Passed a format string - eg "lt%d" it will try and find a suitable 1343 * id. It scans list of devices to build up a free map, then chooses 1344 * the first empty slot. The caller must hold the dev_base or rtnl lock 1345 * while allocating the name and adding the device in order to avoid 1346 * duplicates. 1347 * Limited to bits_per_byte * page size devices (ie 32K on most platforms). 1348 * Returns the number of the unit assigned or a negative errno code. 1349 */ 1350 1351 static int __dev_alloc_name(struct net *net, const char *name, char *res) 1352 { 1353 int i = 0; 1354 const char *p; 1355 const int max_netdevices = 8*PAGE_SIZE; 1356 unsigned long *inuse; 1357 struct net_device *d; 1358 char buf[IFNAMSIZ]; 1359 1360 /* Verify the string as this thing may have come from the user. 1361 * There must be one "%d" and no other "%" characters. 1362 */ 1363 p = strchr(name, '%'); 1364 if (!p || p[1] != 'd' || strchr(p + 2, '%')) 1365 return -EINVAL; 1366 1367 /* Use one page as a bit array of possible slots */ 1368 inuse = bitmap_zalloc(max_netdevices, GFP_ATOMIC); 1369 if (!inuse) 1370 return -ENOMEM; 1371 1372 for_each_netdev(net, d) { 1373 struct netdev_name_node *name_node; 1374 1375 netdev_for_each_altname(d, name_node) { 1376 if (!sscanf(name_node->name, name, &i)) 1377 continue; 1378 if (i < 0 || i >= max_netdevices) 1379 continue; 1380 1381 /* avoid cases where sscanf is not exact inverse of printf */ 1382 snprintf(buf, IFNAMSIZ, name, i); 1383 if (!strncmp(buf, name_node->name, IFNAMSIZ)) 1384 __set_bit(i, inuse); 1385 } 1386 if (!sscanf(d->name, name, &i)) 1387 continue; 1388 if (i < 0 || i >= max_netdevices) 1389 continue; 1390 1391 /* avoid cases where sscanf is not exact inverse of printf */ 1392 snprintf(buf, IFNAMSIZ, name, i); 1393 if (!strncmp(buf, d->name, IFNAMSIZ)) 1394 __set_bit(i, inuse); 1395 } 1396 1397 i = find_first_zero_bit(inuse, max_netdevices); 1398 bitmap_free(inuse); 1399 if (i == max_netdevices) 1400 return -ENFILE; 1401 1402 /* 'res' and 'name' could overlap, use 'buf' as an intermediate buffer */ 1403 strscpy(buf, name, IFNAMSIZ); 1404 snprintf(res, IFNAMSIZ, buf, i); 1405 return i; 1406 } 1407 1408 /* Returns negative errno or allocated unit id (see __dev_alloc_name()) */ 1409 static int dev_prep_valid_name(struct net *net, struct net_device *dev, 1410 const char *want_name, char *out_name, 1411 int dup_errno) 1412 { 1413 if (!dev_valid_name(want_name)) 1414 return -EINVAL; 1415 1416 if (strchr(want_name, '%')) 1417 return __dev_alloc_name(net, want_name, out_name); 1418 1419 if (netdev_name_in_use(net, want_name)) 1420 return -dup_errno; 1421 if (out_name != want_name) 1422 strscpy(out_name, want_name, IFNAMSIZ); 1423 return 0; 1424 } 1425 1426 /** 1427 * dev_alloc_name - allocate a name for a device 1428 * @dev: device 1429 * @name: name format string 1430 * 1431 * Passed a format string - eg "lt%d" it will try and find a suitable 1432 * id. It scans list of devices to build up a free map, then chooses 1433 * the first empty slot. The caller must hold the dev_base or rtnl lock 1434 * while allocating the name and adding the device in order to avoid 1435 * duplicates. 1436 * Limited to bits_per_byte * page size devices (ie 32K on most platforms). 1437 * Returns the number of the unit assigned or a negative errno code. 1438 */ 1439 1440 int dev_alloc_name(struct net_device *dev, const char *name) 1441 { 1442 return dev_prep_valid_name(dev_net(dev), dev, name, dev->name, ENFILE); 1443 } 1444 EXPORT_SYMBOL(dev_alloc_name); 1445 1446 static int dev_get_valid_name(struct net *net, struct net_device *dev, 1447 const char *name) 1448 { 1449 int ret; 1450 1451 ret = dev_prep_valid_name(net, dev, name, dev->name, EEXIST); 1452 return ret < 0 ? ret : 0; 1453 } 1454 1455 int netif_change_name(struct net_device *dev, const char *newname) 1456 { 1457 struct net *net = dev_net(dev); 1458 unsigned char old_assign_type; 1459 char oldname[IFNAMSIZ]; 1460 int err = 0; 1461 int ret; 1462 1463 ASSERT_RTNL_NET(net); 1464 1465 if (!strncmp(newname, dev->name, IFNAMSIZ)) 1466 return 0; 1467 1468 memcpy(oldname, dev->name, IFNAMSIZ); 1469 1470 write_seqlock_bh(&netdev_rename_lock); 1471 err = dev_get_valid_name(net, dev, newname); 1472 write_sequnlock_bh(&netdev_rename_lock); 1473 1474 if (err < 0) 1475 return err; 1476 1477 if (oldname[0] && !strchr(oldname, '%')) 1478 netdev_info(dev, "renamed from %s%s\n", oldname, 1479 dev->flags & IFF_UP ? " (while UP)" : ""); 1480 1481 old_assign_type = dev->name_assign_type; 1482 WRITE_ONCE(dev->name_assign_type, NET_NAME_RENAMED); 1483 1484 rollback: 1485 ret = device_rename(&dev->dev, dev->name); 1486 if (ret) { 1487 write_seqlock_bh(&netdev_rename_lock); 1488 memcpy(dev->name, oldname, IFNAMSIZ); 1489 write_sequnlock_bh(&netdev_rename_lock); 1490 WRITE_ONCE(dev->name_assign_type, old_assign_type); 1491 return ret; 1492 } 1493 1494 netdev_adjacent_rename_links(dev, oldname); 1495 1496 netdev_name_node_del(dev->name_node); 1497 1498 synchronize_net(); 1499 1500 netdev_name_node_add(net, dev->name_node); 1501 1502 ret = call_netdevice_notifiers(NETDEV_CHANGENAME, dev); 1503 ret = notifier_to_errno(ret); 1504 1505 if (ret) { 1506 /* err >= 0 after dev_alloc_name() or stores the first errno */ 1507 if (err >= 0) { 1508 err = ret; 1509 write_seqlock_bh(&netdev_rename_lock); 1510 memcpy(dev->name, oldname, IFNAMSIZ); 1511 write_sequnlock_bh(&netdev_rename_lock); 1512 memcpy(oldname, newname, IFNAMSIZ); 1513 WRITE_ONCE(dev->name_assign_type, old_assign_type); 1514 old_assign_type = NET_NAME_RENAMED; 1515 goto rollback; 1516 } else { 1517 netdev_err(dev, "name change rollback failed: %d\n", 1518 ret); 1519 } 1520 } 1521 1522 return err; 1523 } 1524 1525 int netif_set_alias(struct net_device *dev, const char *alias, size_t len) 1526 { 1527 struct dev_ifalias *new_alias = NULL; 1528 1529 if (len >= IFALIASZ) 1530 return -EINVAL; 1531 1532 if (len) { 1533 new_alias = kmalloc(sizeof(*new_alias) + len + 1, GFP_KERNEL); 1534 if (!new_alias) 1535 return -ENOMEM; 1536 1537 memcpy(new_alias->ifalias, alias, len); 1538 new_alias->ifalias[len] = 0; 1539 } 1540 1541 mutex_lock(&ifalias_mutex); 1542 new_alias = rcu_replace_pointer(dev->ifalias, new_alias, 1543 mutex_is_locked(&ifalias_mutex)); 1544 mutex_unlock(&ifalias_mutex); 1545 1546 if (new_alias) 1547 kfree_rcu(new_alias, rcuhead); 1548 1549 return len; 1550 } 1551 1552 /** 1553 * dev_get_alias - get ifalias of a device 1554 * @dev: device 1555 * @name: buffer to store name of ifalias 1556 * @len: size of buffer 1557 * 1558 * get ifalias for a device. Caller must make sure dev cannot go 1559 * away, e.g. rcu read lock or own a reference count to device. 1560 */ 1561 int dev_get_alias(const struct net_device *dev, char *name, size_t len) 1562 { 1563 const struct dev_ifalias *alias; 1564 int ret = 0; 1565 1566 rcu_read_lock(); 1567 alias = rcu_dereference(dev->ifalias); 1568 if (alias) 1569 ret = snprintf(name, len, "%s", alias->ifalias); 1570 rcu_read_unlock(); 1571 1572 return ret; 1573 } 1574 1575 /** 1576 * netdev_features_change - device changes features 1577 * @dev: device to cause notification 1578 * 1579 * Called to indicate a device has changed features. 1580 */ 1581 void netdev_features_change(struct net_device *dev) 1582 { 1583 call_netdevice_notifiers(NETDEV_FEAT_CHANGE, dev); 1584 } 1585 EXPORT_SYMBOL(netdev_features_change); 1586 1587 void netif_state_change(struct net_device *dev) 1588 { 1589 netdev_ops_assert_locked_or_invisible(dev); 1590 1591 if (dev->flags & IFF_UP) { 1592 struct netdev_notifier_change_info change_info = { 1593 .info.dev = dev, 1594 }; 1595 1596 call_netdevice_notifiers_info(NETDEV_CHANGE, 1597 &change_info.info); 1598 rtmsg_ifinfo(RTM_NEWLINK, dev, 0, GFP_KERNEL, 0, NULL); 1599 } 1600 } 1601 1602 /** 1603 * __netdev_notify_peers - notify network peers about existence of @dev, 1604 * to be called when rtnl lock is already held. 1605 * @dev: network device 1606 * 1607 * Generate traffic such that interested network peers are aware of 1608 * @dev, such as by generating a gratuitous ARP. This may be used when 1609 * a device wants to inform the rest of the network about some sort of 1610 * reconfiguration such as a failover event or virtual machine 1611 * migration. 1612 */ 1613 void __netdev_notify_peers(struct net_device *dev) 1614 { 1615 ASSERT_RTNL(); 1616 call_netdevice_notifiers(NETDEV_NOTIFY_PEERS, dev); 1617 call_netdevice_notifiers(NETDEV_RESEND_IGMP, dev); 1618 } 1619 EXPORT_SYMBOL(__netdev_notify_peers); 1620 1621 /** 1622 * netdev_notify_peers - notify network peers about existence of @dev 1623 * @dev: network device 1624 * 1625 * Generate traffic such that interested network peers are aware of 1626 * @dev, such as by generating a gratuitous ARP. This may be used when 1627 * a device wants to inform the rest of the network about some sort of 1628 * reconfiguration such as a failover event or virtual machine 1629 * migration. 1630 */ 1631 void netdev_notify_peers(struct net_device *dev) 1632 { 1633 rtnl_lock(); 1634 __netdev_notify_peers(dev); 1635 rtnl_unlock(); 1636 } 1637 EXPORT_SYMBOL(netdev_notify_peers); 1638 1639 static int napi_threaded_poll(void *data); 1640 1641 static int napi_kthread_create(struct napi_struct *n) 1642 { 1643 int err = 0; 1644 1645 /* Create and wake up the kthread once to put it in 1646 * TASK_INTERRUPTIBLE mode to avoid the blocked task 1647 * warning and work with loadavg. 1648 */ 1649 n->thread = kthread_run(napi_threaded_poll, n, "napi/%s-%d", 1650 n->dev->name, n->napi_id); 1651 if (IS_ERR(n->thread)) { 1652 err = PTR_ERR(n->thread); 1653 pr_err("kthread_run failed with err %d\n", err); 1654 n->thread = NULL; 1655 } 1656 1657 return err; 1658 } 1659 1660 static int __dev_open(struct net_device *dev, struct netlink_ext_ack *extack) 1661 { 1662 const struct net_device_ops *ops = dev->netdev_ops; 1663 int ret; 1664 1665 ASSERT_RTNL(); 1666 dev_addr_check(dev); 1667 1668 if (!netif_device_present(dev)) { 1669 /* may be detached because parent is runtime-suspended */ 1670 if (dev->dev.parent) 1671 pm_runtime_resume(dev->dev.parent); 1672 if (!netif_device_present(dev)) 1673 return -ENODEV; 1674 } 1675 1676 /* Block netpoll from trying to do any rx path servicing. 1677 * If we don't do this there is a chance ndo_poll_controller 1678 * or ndo_poll may be running while we open the device 1679 */ 1680 netpoll_poll_disable(dev); 1681 1682 ret = call_netdevice_notifiers_extack(NETDEV_PRE_UP, dev, extack); 1683 ret = notifier_to_errno(ret); 1684 if (ret) 1685 return ret; 1686 1687 set_bit(__LINK_STATE_START, &dev->state); 1688 1689 netdev_ops_assert_locked(dev); 1690 1691 if (ops->ndo_validate_addr) 1692 ret = ops->ndo_validate_addr(dev); 1693 1694 if (!ret && ops->ndo_open) 1695 ret = ops->ndo_open(dev); 1696 1697 netpoll_poll_enable(dev); 1698 1699 if (ret) 1700 clear_bit(__LINK_STATE_START, &dev->state); 1701 else { 1702 netif_set_up(dev, true); 1703 dev_set_rx_mode(dev); 1704 dev_activate(dev); 1705 add_device_randomness(dev->dev_addr, dev->addr_len); 1706 } 1707 1708 return ret; 1709 } 1710 1711 int netif_open(struct net_device *dev, struct netlink_ext_ack *extack) 1712 { 1713 int ret; 1714 1715 if (dev->flags & IFF_UP) 1716 return 0; 1717 1718 ret = __dev_open(dev, extack); 1719 if (ret < 0) 1720 return ret; 1721 1722 rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP | IFF_RUNNING, GFP_KERNEL, 0, NULL); 1723 call_netdevice_notifiers(NETDEV_UP, dev); 1724 1725 return ret; 1726 } 1727 EXPORT_SYMBOL(netif_open); 1728 1729 static void __dev_close_many(struct list_head *head) 1730 { 1731 struct net_device *dev; 1732 1733 ASSERT_RTNL(); 1734 might_sleep(); 1735 1736 list_for_each_entry(dev, head, close_list) { 1737 /* Temporarily disable netpoll until the interface is down */ 1738 netpoll_poll_disable(dev); 1739 1740 call_netdevice_notifiers(NETDEV_GOING_DOWN, dev); 1741 1742 clear_bit(__LINK_STATE_START, &dev->state); 1743 1744 /* Synchronize to scheduled poll. We cannot touch poll list, it 1745 * can be even on different cpu. So just clear netif_running(). 1746 * 1747 * dev->stop() will invoke napi_disable() on all of it's 1748 * napi_struct instances on this device. 1749 */ 1750 smp_mb__after_atomic(); /* Commit netif_running(). */ 1751 } 1752 1753 dev_deactivate_many(head); 1754 1755 list_for_each_entry(dev, head, close_list) { 1756 const struct net_device_ops *ops = dev->netdev_ops; 1757 1758 /* 1759 * Call the device specific close. This cannot fail. 1760 * Only if device is UP 1761 * 1762 * We allow it to be called even after a DETACH hot-plug 1763 * event. 1764 */ 1765 1766 netdev_ops_assert_locked(dev); 1767 1768 if (ops->ndo_stop) 1769 ops->ndo_stop(dev); 1770 1771 netif_set_up(dev, false); 1772 netpoll_poll_enable(dev); 1773 } 1774 } 1775 1776 static void __dev_close(struct net_device *dev) 1777 { 1778 LIST_HEAD(single); 1779 1780 list_add(&dev->close_list, &single); 1781 __dev_close_many(&single); 1782 list_del(&single); 1783 } 1784 1785 void netif_close_many(struct list_head *head, bool unlink) 1786 { 1787 struct net_device *dev, *tmp; 1788 1789 /* Remove the devices that don't need to be closed */ 1790 list_for_each_entry_safe(dev, tmp, head, close_list) 1791 if (!(dev->flags & IFF_UP)) 1792 list_del_init(&dev->close_list); 1793 1794 __dev_close_many(head); 1795 1796 list_for_each_entry_safe(dev, tmp, head, close_list) { 1797 rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP | IFF_RUNNING, GFP_KERNEL, 0, NULL); 1798 call_netdevice_notifiers(NETDEV_DOWN, dev); 1799 if (unlink) 1800 list_del_init(&dev->close_list); 1801 } 1802 } 1803 EXPORT_SYMBOL_NS_GPL(netif_close_many, "NETDEV_INTERNAL"); 1804 1805 void netif_close(struct net_device *dev) 1806 { 1807 if (dev->flags & IFF_UP) { 1808 LIST_HEAD(single); 1809 1810 list_add(&dev->close_list, &single); 1811 netif_close_many(&single, true); 1812 list_del(&single); 1813 } 1814 } 1815 EXPORT_SYMBOL(netif_close); 1816 1817 void netif_disable_lro(struct net_device *dev) 1818 { 1819 struct net_device *lower_dev; 1820 struct list_head *iter; 1821 1822 dev->wanted_features &= ~NETIF_F_LRO; 1823 netdev_update_features(dev); 1824 1825 if (unlikely(dev->features & NETIF_F_LRO)) 1826 netdev_WARN(dev, "failed to disable LRO!\n"); 1827 1828 netdev_for_each_lower_dev(dev, lower_dev, iter) { 1829 netdev_lock_ops(lower_dev); 1830 netif_disable_lro(lower_dev); 1831 netdev_unlock_ops(lower_dev); 1832 } 1833 } 1834 EXPORT_IPV6_MOD(netif_disable_lro); 1835 1836 /** 1837 * dev_disable_gro_hw - disable HW Generic Receive Offload on a device 1838 * @dev: device 1839 * 1840 * Disable HW Generic Receive Offload (GRO_HW) on a net device. Must be 1841 * called under RTNL. This is needed if Generic XDP is installed on 1842 * the device. 1843 */ 1844 static void dev_disable_gro_hw(struct net_device *dev) 1845 { 1846 dev->wanted_features &= ~NETIF_F_GRO_HW; 1847 netdev_update_features(dev); 1848 1849 if (unlikely(dev->features & NETIF_F_GRO_HW)) 1850 netdev_WARN(dev, "failed to disable GRO_HW!\n"); 1851 } 1852 1853 const char *netdev_cmd_to_name(enum netdev_cmd cmd) 1854 { 1855 #define N(val) \ 1856 case NETDEV_##val: \ 1857 return "NETDEV_" __stringify(val); 1858 switch (cmd) { 1859 N(UP) N(DOWN) N(REBOOT) N(CHANGE) N(REGISTER) N(UNREGISTER) 1860 N(CHANGEMTU) N(CHANGEADDR) N(GOING_DOWN) N(CHANGENAME) N(FEAT_CHANGE) 1861 N(BONDING_FAILOVER) N(PRE_UP) N(PRE_TYPE_CHANGE) N(POST_TYPE_CHANGE) 1862 N(POST_INIT) N(PRE_UNINIT) N(RELEASE) N(NOTIFY_PEERS) N(JOIN) 1863 N(CHANGEUPPER) N(RESEND_IGMP) N(PRECHANGEMTU) N(CHANGEINFODATA) 1864 N(BONDING_INFO) N(PRECHANGEUPPER) N(CHANGELOWERSTATE) 1865 N(UDP_TUNNEL_PUSH_INFO) N(UDP_TUNNEL_DROP_INFO) N(CHANGE_TX_QUEUE_LEN) 1866 N(CVLAN_FILTER_PUSH_INFO) N(CVLAN_FILTER_DROP_INFO) 1867 N(SVLAN_FILTER_PUSH_INFO) N(SVLAN_FILTER_DROP_INFO) 1868 N(PRE_CHANGEADDR) N(OFFLOAD_XSTATS_ENABLE) N(OFFLOAD_XSTATS_DISABLE) 1869 N(OFFLOAD_XSTATS_REPORT_USED) N(OFFLOAD_XSTATS_REPORT_DELTA) 1870 N(XDP_FEAT_CHANGE) 1871 } 1872 #undef N 1873 return "UNKNOWN_NETDEV_EVENT"; 1874 } 1875 EXPORT_SYMBOL_GPL(netdev_cmd_to_name); 1876 1877 static int call_netdevice_notifier(struct notifier_block *nb, unsigned long val, 1878 struct net_device *dev) 1879 { 1880 struct netdev_notifier_info info = { 1881 .dev = dev, 1882 }; 1883 1884 return nb->notifier_call(nb, val, &info); 1885 } 1886 1887 static int call_netdevice_register_notifiers(struct notifier_block *nb, 1888 struct net_device *dev) 1889 { 1890 int err; 1891 1892 err = call_netdevice_notifier(nb, NETDEV_REGISTER, dev); 1893 err = notifier_to_errno(err); 1894 if (err) 1895 return err; 1896 1897 if (!(dev->flags & IFF_UP)) 1898 return 0; 1899 1900 call_netdevice_notifier(nb, NETDEV_UP, dev); 1901 return 0; 1902 } 1903 1904 static void call_netdevice_unregister_notifiers(struct notifier_block *nb, 1905 struct net_device *dev) 1906 { 1907 if (dev->flags & IFF_UP) { 1908 call_netdevice_notifier(nb, NETDEV_GOING_DOWN, 1909 dev); 1910 call_netdevice_notifier(nb, NETDEV_DOWN, dev); 1911 } 1912 call_netdevice_notifier(nb, NETDEV_UNREGISTER, dev); 1913 } 1914 1915 static int call_netdevice_register_net_notifiers(struct notifier_block *nb, 1916 struct net *net) 1917 { 1918 struct net_device *dev; 1919 int err; 1920 1921 for_each_netdev(net, dev) { 1922 netdev_lock_ops(dev); 1923 err = call_netdevice_register_notifiers(nb, dev); 1924 netdev_unlock_ops(dev); 1925 if (err) 1926 goto rollback; 1927 } 1928 return 0; 1929 1930 rollback: 1931 for_each_netdev_continue_reverse(net, dev) 1932 call_netdevice_unregister_notifiers(nb, dev); 1933 return err; 1934 } 1935 1936 static void call_netdevice_unregister_net_notifiers(struct notifier_block *nb, 1937 struct net *net) 1938 { 1939 struct net_device *dev; 1940 1941 for_each_netdev(net, dev) 1942 call_netdevice_unregister_notifiers(nb, dev); 1943 } 1944 1945 static int dev_boot_phase = 1; 1946 1947 /** 1948 * register_netdevice_notifier - register a network notifier block 1949 * @nb: notifier 1950 * 1951 * Register a notifier to be called when network device events occur. 1952 * The notifier passed is linked into the kernel structures and must 1953 * not be reused until it has been unregistered. A negative errno code 1954 * is returned on a failure. 1955 * 1956 * When registered all registration and up events are replayed 1957 * to the new notifier to allow device to have a race free 1958 * view of the network device list. 1959 */ 1960 1961 int register_netdevice_notifier(struct notifier_block *nb) 1962 { 1963 struct net *net; 1964 int err; 1965 1966 /* Close race with setup_net() and cleanup_net() */ 1967 down_write(&pernet_ops_rwsem); 1968 1969 /* When RTNL is removed, we need protection for netdev_chain. */ 1970 rtnl_lock(); 1971 1972 err = raw_notifier_chain_register(&netdev_chain, nb); 1973 if (err) 1974 goto unlock; 1975 if (dev_boot_phase) 1976 goto unlock; 1977 for_each_net(net) { 1978 __rtnl_net_lock(net); 1979 err = call_netdevice_register_net_notifiers(nb, net); 1980 __rtnl_net_unlock(net); 1981 if (err) 1982 goto rollback; 1983 } 1984 1985 unlock: 1986 rtnl_unlock(); 1987 up_write(&pernet_ops_rwsem); 1988 return err; 1989 1990 rollback: 1991 for_each_net_continue_reverse(net) { 1992 __rtnl_net_lock(net); 1993 call_netdevice_unregister_net_notifiers(nb, net); 1994 __rtnl_net_unlock(net); 1995 } 1996 1997 raw_notifier_chain_unregister(&netdev_chain, nb); 1998 goto unlock; 1999 } 2000 EXPORT_SYMBOL(register_netdevice_notifier); 2001 2002 /** 2003 * unregister_netdevice_notifier - unregister a network notifier block 2004 * @nb: notifier 2005 * 2006 * Unregister a notifier previously registered by 2007 * register_netdevice_notifier(). The notifier is unlinked into the 2008 * kernel structures and may then be reused. A negative errno code 2009 * is returned on a failure. 2010 * 2011 * After unregistering unregister and down device events are synthesized 2012 * for all devices on the device list to the removed notifier to remove 2013 * the need for special case cleanup code. 2014 */ 2015 2016 int unregister_netdevice_notifier(struct notifier_block *nb) 2017 { 2018 struct net *net; 2019 int err; 2020 2021 /* Close race with setup_net() and cleanup_net() */ 2022 down_write(&pernet_ops_rwsem); 2023 rtnl_lock(); 2024 err = raw_notifier_chain_unregister(&netdev_chain, nb); 2025 if (err) 2026 goto unlock; 2027 2028 for_each_net(net) { 2029 __rtnl_net_lock(net); 2030 call_netdevice_unregister_net_notifiers(nb, net); 2031 __rtnl_net_unlock(net); 2032 } 2033 2034 unlock: 2035 rtnl_unlock(); 2036 up_write(&pernet_ops_rwsem); 2037 return err; 2038 } 2039 EXPORT_SYMBOL(unregister_netdevice_notifier); 2040 2041 static int __register_netdevice_notifier_net(struct net *net, 2042 struct notifier_block *nb, 2043 bool ignore_call_fail) 2044 { 2045 int err; 2046 2047 err = raw_notifier_chain_register(&net->netdev_chain, nb); 2048 if (err) 2049 return err; 2050 if (dev_boot_phase) 2051 return 0; 2052 2053 err = call_netdevice_register_net_notifiers(nb, net); 2054 if (err && !ignore_call_fail) 2055 goto chain_unregister; 2056 2057 return 0; 2058 2059 chain_unregister: 2060 raw_notifier_chain_unregister(&net->netdev_chain, nb); 2061 return err; 2062 } 2063 2064 static int __unregister_netdevice_notifier_net(struct net *net, 2065 struct notifier_block *nb) 2066 { 2067 int err; 2068 2069 err = raw_notifier_chain_unregister(&net->netdev_chain, nb); 2070 if (err) 2071 return err; 2072 2073 call_netdevice_unregister_net_notifiers(nb, net); 2074 return 0; 2075 } 2076 2077 /** 2078 * register_netdevice_notifier_net - register a per-netns network notifier block 2079 * @net: network namespace 2080 * @nb: notifier 2081 * 2082 * Register a notifier to be called when network device events occur. 2083 * The notifier passed is linked into the kernel structures and must 2084 * not be reused until it has been unregistered. A negative errno code 2085 * is returned on a failure. 2086 * 2087 * When registered all registration and up events are replayed 2088 * to the new notifier to allow device to have a race free 2089 * view of the network device list. 2090 */ 2091 2092 int register_netdevice_notifier_net(struct net *net, struct notifier_block *nb) 2093 { 2094 int err; 2095 2096 rtnl_net_lock(net); 2097 err = __register_netdevice_notifier_net(net, nb, false); 2098 rtnl_net_unlock(net); 2099 2100 return err; 2101 } 2102 EXPORT_SYMBOL(register_netdevice_notifier_net); 2103 2104 /** 2105 * unregister_netdevice_notifier_net - unregister a per-netns 2106 * network notifier block 2107 * @net: network namespace 2108 * @nb: notifier 2109 * 2110 * Unregister a notifier previously registered by 2111 * register_netdevice_notifier_net(). The notifier is unlinked from the 2112 * kernel structures and may then be reused. A negative errno code 2113 * is returned on a failure. 2114 * 2115 * After unregistering unregister and down device events are synthesized 2116 * for all devices on the device list to the removed notifier to remove 2117 * the need for special case cleanup code. 2118 */ 2119 2120 int unregister_netdevice_notifier_net(struct net *net, 2121 struct notifier_block *nb) 2122 { 2123 int err; 2124 2125 rtnl_net_lock(net); 2126 err = __unregister_netdevice_notifier_net(net, nb); 2127 rtnl_net_unlock(net); 2128 2129 return err; 2130 } 2131 EXPORT_SYMBOL(unregister_netdevice_notifier_net); 2132 2133 static void __move_netdevice_notifier_net(struct net *src_net, 2134 struct net *dst_net, 2135 struct notifier_block *nb) 2136 { 2137 __unregister_netdevice_notifier_net(src_net, nb); 2138 __register_netdevice_notifier_net(dst_net, nb, true); 2139 } 2140 2141 static void rtnl_net_dev_lock(struct net_device *dev) 2142 { 2143 bool again; 2144 2145 do { 2146 struct net *net; 2147 2148 again = false; 2149 2150 /* netns might be being dismantled. */ 2151 rcu_read_lock(); 2152 net = dev_net_rcu(dev); 2153 net_passive_inc(net); 2154 rcu_read_unlock(); 2155 2156 rtnl_net_lock(net); 2157 2158 #ifdef CONFIG_NET_NS 2159 /* dev might have been moved to another netns. */ 2160 if (!net_eq(net, rcu_access_pointer(dev->nd_net.net))) { 2161 rtnl_net_unlock(net); 2162 net_passive_dec(net); 2163 again = true; 2164 } 2165 #endif 2166 } while (again); 2167 } 2168 2169 static void rtnl_net_dev_unlock(struct net_device *dev) 2170 { 2171 struct net *net = dev_net(dev); 2172 2173 rtnl_net_unlock(net); 2174 net_passive_dec(net); 2175 } 2176 2177 int register_netdevice_notifier_dev_net(struct net_device *dev, 2178 struct notifier_block *nb, 2179 struct netdev_net_notifier *nn) 2180 { 2181 int err; 2182 2183 rtnl_net_dev_lock(dev); 2184 err = __register_netdevice_notifier_net(dev_net(dev), nb, false); 2185 if (!err) { 2186 nn->nb = nb; 2187 list_add(&nn->list, &dev->net_notifier_list); 2188 } 2189 rtnl_net_dev_unlock(dev); 2190 2191 return err; 2192 } 2193 EXPORT_SYMBOL(register_netdevice_notifier_dev_net); 2194 2195 int unregister_netdevice_notifier_dev_net(struct net_device *dev, 2196 struct notifier_block *nb, 2197 struct netdev_net_notifier *nn) 2198 { 2199 int err; 2200 2201 rtnl_net_dev_lock(dev); 2202 list_del(&nn->list); 2203 err = __unregister_netdevice_notifier_net(dev_net(dev), nb); 2204 rtnl_net_dev_unlock(dev); 2205 2206 return err; 2207 } 2208 EXPORT_SYMBOL(unregister_netdevice_notifier_dev_net); 2209 2210 static void move_netdevice_notifiers_dev_net(struct net_device *dev, 2211 struct net *net) 2212 { 2213 struct netdev_net_notifier *nn; 2214 2215 list_for_each_entry(nn, &dev->net_notifier_list, list) 2216 __move_netdevice_notifier_net(dev_net(dev), net, nn->nb); 2217 } 2218 2219 /** 2220 * call_netdevice_notifiers_info - call all network notifier blocks 2221 * @val: value passed unmodified to notifier function 2222 * @info: notifier information data 2223 * 2224 * Call all network notifier blocks. Parameters and return value 2225 * are as for raw_notifier_call_chain(). 2226 */ 2227 2228 int call_netdevice_notifiers_info(unsigned long val, 2229 struct netdev_notifier_info *info) 2230 { 2231 struct net *net = dev_net(info->dev); 2232 int ret; 2233 2234 ASSERT_RTNL(); 2235 2236 /* Run per-netns notifier block chain first, then run the global one. 2237 * Hopefully, one day, the global one is going to be removed after 2238 * all notifier block registrators get converted to be per-netns. 2239 */ 2240 ret = raw_notifier_call_chain(&net->netdev_chain, val, info); 2241 if (ret & NOTIFY_STOP_MASK) 2242 return ret; 2243 return raw_notifier_call_chain(&netdev_chain, val, info); 2244 } 2245 2246 /** 2247 * call_netdevice_notifiers_info_robust - call per-netns notifier blocks 2248 * for and rollback on error 2249 * @val_up: value passed unmodified to notifier function 2250 * @val_down: value passed unmodified to the notifier function when 2251 * recovering from an error on @val_up 2252 * @info: notifier information data 2253 * 2254 * Call all per-netns network notifier blocks, but not notifier blocks on 2255 * the global notifier chain. Parameters and return value are as for 2256 * raw_notifier_call_chain_robust(). 2257 */ 2258 2259 static int 2260 call_netdevice_notifiers_info_robust(unsigned long val_up, 2261 unsigned long val_down, 2262 struct netdev_notifier_info *info) 2263 { 2264 struct net *net = dev_net(info->dev); 2265 2266 ASSERT_RTNL(); 2267 2268 return raw_notifier_call_chain_robust(&net->netdev_chain, 2269 val_up, val_down, info); 2270 } 2271 2272 static int call_netdevice_notifiers_extack(unsigned long val, 2273 struct net_device *dev, 2274 struct netlink_ext_ack *extack) 2275 { 2276 struct netdev_notifier_info info = { 2277 .dev = dev, 2278 .extack = extack, 2279 }; 2280 2281 return call_netdevice_notifiers_info(val, &info); 2282 } 2283 2284 /** 2285 * call_netdevice_notifiers - call all network notifier blocks 2286 * @val: value passed unmodified to notifier function 2287 * @dev: net_device pointer passed unmodified to notifier function 2288 * 2289 * Call all network notifier blocks. Parameters and return value 2290 * are as for raw_notifier_call_chain(). 2291 */ 2292 2293 int call_netdevice_notifiers(unsigned long val, struct net_device *dev) 2294 { 2295 return call_netdevice_notifiers_extack(val, dev, NULL); 2296 } 2297 EXPORT_SYMBOL(call_netdevice_notifiers); 2298 2299 /** 2300 * call_netdevice_notifiers_mtu - call all network notifier blocks 2301 * @val: value passed unmodified to notifier function 2302 * @dev: net_device pointer passed unmodified to notifier function 2303 * @arg: additional u32 argument passed to the notifier function 2304 * 2305 * Call all network notifier blocks. Parameters and return value 2306 * are as for raw_notifier_call_chain(). 2307 */ 2308 static int call_netdevice_notifiers_mtu(unsigned long val, 2309 struct net_device *dev, u32 arg) 2310 { 2311 struct netdev_notifier_info_ext info = { 2312 .info.dev = dev, 2313 .ext.mtu = arg, 2314 }; 2315 2316 BUILD_BUG_ON(offsetof(struct netdev_notifier_info_ext, info) != 0); 2317 2318 return call_netdevice_notifiers_info(val, &info.info); 2319 } 2320 2321 #ifdef CONFIG_NET_INGRESS 2322 static DEFINE_STATIC_KEY_FALSE(ingress_needed_key); 2323 2324 void net_inc_ingress_queue(void) 2325 { 2326 static_branch_inc(&ingress_needed_key); 2327 } 2328 EXPORT_SYMBOL_GPL(net_inc_ingress_queue); 2329 2330 void net_dec_ingress_queue(void) 2331 { 2332 static_branch_dec(&ingress_needed_key); 2333 } 2334 EXPORT_SYMBOL_GPL(net_dec_ingress_queue); 2335 #endif 2336 2337 #ifdef CONFIG_NET_EGRESS 2338 static DEFINE_STATIC_KEY_FALSE(egress_needed_key); 2339 2340 void net_inc_egress_queue(void) 2341 { 2342 static_branch_inc(&egress_needed_key); 2343 } 2344 EXPORT_SYMBOL_GPL(net_inc_egress_queue); 2345 2346 void net_dec_egress_queue(void) 2347 { 2348 static_branch_dec(&egress_needed_key); 2349 } 2350 EXPORT_SYMBOL_GPL(net_dec_egress_queue); 2351 #endif 2352 2353 #ifdef CONFIG_NET_CLS_ACT 2354 DEFINE_STATIC_KEY_FALSE(tcf_sw_enabled_key); 2355 EXPORT_SYMBOL(tcf_sw_enabled_key); 2356 #endif 2357 2358 DEFINE_STATIC_KEY_FALSE(netstamp_needed_key); 2359 EXPORT_SYMBOL(netstamp_needed_key); 2360 #ifdef CONFIG_JUMP_LABEL 2361 static atomic_t netstamp_needed_deferred; 2362 static atomic_t netstamp_wanted; 2363 static void netstamp_clear(struct work_struct *work) 2364 { 2365 int deferred = atomic_xchg(&netstamp_needed_deferred, 0); 2366 int wanted; 2367 2368 wanted = atomic_add_return(deferred, &netstamp_wanted); 2369 if (wanted > 0) 2370 static_branch_enable(&netstamp_needed_key); 2371 else 2372 static_branch_disable(&netstamp_needed_key); 2373 } 2374 static DECLARE_WORK(netstamp_work, netstamp_clear); 2375 #endif 2376 2377 void net_enable_timestamp(void) 2378 { 2379 #ifdef CONFIG_JUMP_LABEL 2380 int wanted = atomic_read(&netstamp_wanted); 2381 2382 while (wanted > 0) { 2383 if (atomic_try_cmpxchg(&netstamp_wanted, &wanted, wanted + 1)) 2384 return; 2385 } 2386 atomic_inc(&netstamp_needed_deferred); 2387 schedule_work(&netstamp_work); 2388 #else 2389 static_branch_inc(&netstamp_needed_key); 2390 #endif 2391 } 2392 EXPORT_SYMBOL(net_enable_timestamp); 2393 2394 void net_disable_timestamp(void) 2395 { 2396 #ifdef CONFIG_JUMP_LABEL 2397 int wanted = atomic_read(&netstamp_wanted); 2398 2399 while (wanted > 1) { 2400 if (atomic_try_cmpxchg(&netstamp_wanted, &wanted, wanted - 1)) 2401 return; 2402 } 2403 atomic_dec(&netstamp_needed_deferred); 2404 schedule_work(&netstamp_work); 2405 #else 2406 static_branch_dec(&netstamp_needed_key); 2407 #endif 2408 } 2409 EXPORT_SYMBOL(net_disable_timestamp); 2410 2411 static inline void net_timestamp_set(struct sk_buff *skb) 2412 { 2413 skb->tstamp = 0; 2414 skb->tstamp_type = SKB_CLOCK_REALTIME; 2415 if (static_branch_unlikely(&netstamp_needed_key)) 2416 skb->tstamp = ktime_get_real(); 2417 } 2418 2419 #define net_timestamp_check(COND, SKB) \ 2420 if (static_branch_unlikely(&netstamp_needed_key)) { \ 2421 if ((COND) && !(SKB)->tstamp) \ 2422 (SKB)->tstamp = ktime_get_real(); \ 2423 } \ 2424 2425 bool is_skb_forwardable(const struct net_device *dev, const struct sk_buff *skb) 2426 { 2427 return __is_skb_forwardable(dev, skb, true); 2428 } 2429 EXPORT_SYMBOL_GPL(is_skb_forwardable); 2430 2431 static int __dev_forward_skb2(struct net_device *dev, struct sk_buff *skb, 2432 bool check_mtu) 2433 { 2434 int ret = ____dev_forward_skb(dev, skb, check_mtu); 2435 2436 if (likely(!ret)) { 2437 skb->protocol = eth_type_trans(skb, dev); 2438 skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN); 2439 } 2440 2441 return ret; 2442 } 2443 2444 int __dev_forward_skb(struct net_device *dev, struct sk_buff *skb) 2445 { 2446 return __dev_forward_skb2(dev, skb, true); 2447 } 2448 EXPORT_SYMBOL_GPL(__dev_forward_skb); 2449 2450 /** 2451 * dev_forward_skb - loopback an skb to another netif 2452 * 2453 * @dev: destination network device 2454 * @skb: buffer to forward 2455 * 2456 * return values: 2457 * NET_RX_SUCCESS (no congestion) 2458 * NET_RX_DROP (packet was dropped, but freed) 2459 * 2460 * dev_forward_skb can be used for injecting an skb from the 2461 * start_xmit function of one device into the receive queue 2462 * of another device. 2463 * 2464 * The receiving device may be in another namespace, so 2465 * we have to clear all information in the skb that could 2466 * impact namespace isolation. 2467 */ 2468 int dev_forward_skb(struct net_device *dev, struct sk_buff *skb) 2469 { 2470 return __dev_forward_skb(dev, skb) ?: netif_rx_internal(skb); 2471 } 2472 EXPORT_SYMBOL_GPL(dev_forward_skb); 2473 2474 int dev_forward_skb_nomtu(struct net_device *dev, struct sk_buff *skb) 2475 { 2476 return __dev_forward_skb2(dev, skb, false) ?: netif_rx_internal(skb); 2477 } 2478 2479 static inline int deliver_skb(struct sk_buff *skb, 2480 struct packet_type *pt_prev, 2481 struct net_device *orig_dev) 2482 { 2483 if (unlikely(skb_orphan_frags_rx(skb, GFP_ATOMIC))) 2484 return -ENOMEM; 2485 refcount_inc(&skb->users); 2486 return pt_prev->func(skb, skb->dev, pt_prev, orig_dev); 2487 } 2488 2489 static inline void deliver_ptype_list_skb(struct sk_buff *skb, 2490 struct packet_type **pt, 2491 struct net_device *orig_dev, 2492 __be16 type, 2493 struct list_head *ptype_list) 2494 { 2495 struct packet_type *ptype, *pt_prev = *pt; 2496 2497 list_for_each_entry_rcu(ptype, ptype_list, list) { 2498 if (ptype->type != type) 2499 continue; 2500 if (pt_prev) 2501 deliver_skb(skb, pt_prev, orig_dev); 2502 pt_prev = ptype; 2503 } 2504 *pt = pt_prev; 2505 } 2506 2507 static inline bool skb_loop_sk(struct packet_type *ptype, struct sk_buff *skb) 2508 { 2509 if (!ptype->af_packet_priv || !skb->sk) 2510 return false; 2511 2512 if (ptype->id_match) 2513 return ptype->id_match(ptype, skb->sk); 2514 else if ((struct sock *)ptype->af_packet_priv == skb->sk) 2515 return true; 2516 2517 return false; 2518 } 2519 2520 /** 2521 * dev_nit_active_rcu - return true if any network interface taps are in use 2522 * 2523 * The caller must hold the RCU lock 2524 * 2525 * @dev: network device to check for the presence of taps 2526 */ 2527 bool dev_nit_active_rcu(const struct net_device *dev) 2528 { 2529 /* Callers may hold either RCU or RCU BH lock */ 2530 WARN_ON_ONCE(!rcu_read_lock_held() && !rcu_read_lock_bh_held()); 2531 2532 return !list_empty(&dev_net(dev)->ptype_all) || 2533 !list_empty(&dev->ptype_all); 2534 } 2535 EXPORT_SYMBOL_GPL(dev_nit_active_rcu); 2536 2537 /* 2538 * Support routine. Sends outgoing frames to any network 2539 * taps currently in use. 2540 */ 2541 2542 void dev_queue_xmit_nit(struct sk_buff *skb, struct net_device *dev) 2543 { 2544 struct packet_type *ptype, *pt_prev = NULL; 2545 struct list_head *ptype_list; 2546 struct sk_buff *skb2 = NULL; 2547 2548 rcu_read_lock(); 2549 ptype_list = &dev_net_rcu(dev)->ptype_all; 2550 again: 2551 list_for_each_entry_rcu(ptype, ptype_list, list) { 2552 if (READ_ONCE(ptype->ignore_outgoing)) 2553 continue; 2554 2555 /* Never send packets back to the socket 2556 * they originated from - MvS ([email protected]) 2557 */ 2558 if (skb_loop_sk(ptype, skb)) 2559 continue; 2560 2561 if (pt_prev) { 2562 deliver_skb(skb2, pt_prev, skb->dev); 2563 pt_prev = ptype; 2564 continue; 2565 } 2566 2567 /* need to clone skb, done only once */ 2568 skb2 = skb_clone(skb, GFP_ATOMIC); 2569 if (!skb2) 2570 goto out_unlock; 2571 2572 net_timestamp_set(skb2); 2573 2574 /* skb->nh should be correctly 2575 * set by sender, so that the second statement is 2576 * just protection against buggy protocols. 2577 */ 2578 skb_reset_mac_header(skb2); 2579 2580 if (skb_network_header(skb2) < skb2->data || 2581 skb_network_header(skb2) > skb_tail_pointer(skb2)) { 2582 net_crit_ratelimited("protocol %04x is buggy, dev %s\n", 2583 ntohs(skb2->protocol), 2584 dev->name); 2585 skb_reset_network_header(skb2); 2586 } 2587 2588 skb2->transport_header = skb2->network_header; 2589 skb2->pkt_type = PACKET_OUTGOING; 2590 pt_prev = ptype; 2591 } 2592 2593 if (ptype_list != &dev->ptype_all) { 2594 ptype_list = &dev->ptype_all; 2595 goto again; 2596 } 2597 out_unlock: 2598 if (pt_prev) { 2599 if (!skb_orphan_frags_rx(skb2, GFP_ATOMIC)) 2600 pt_prev->func(skb2, skb->dev, pt_prev, skb->dev); 2601 else 2602 kfree_skb(skb2); 2603 } 2604 rcu_read_unlock(); 2605 } 2606 EXPORT_SYMBOL_GPL(dev_queue_xmit_nit); 2607 2608 /** 2609 * netif_setup_tc - Handle tc mappings on real_num_tx_queues change 2610 * @dev: Network device 2611 * @txq: number of queues available 2612 * 2613 * If real_num_tx_queues is changed the tc mappings may no longer be 2614 * valid. To resolve this verify the tc mapping remains valid and if 2615 * not NULL the mapping. With no priorities mapping to this 2616 * offset/count pair it will no longer be used. In the worst case TC0 2617 * is invalid nothing can be done so disable priority mappings. If is 2618 * expected that drivers will fix this mapping if they can before 2619 * calling netif_set_real_num_tx_queues. 2620 */ 2621 static void netif_setup_tc(struct net_device *dev, unsigned int txq) 2622 { 2623 int i; 2624 struct netdev_tc_txq *tc = &dev->tc_to_txq[0]; 2625 2626 /* If TC0 is invalidated disable TC mapping */ 2627 if (tc->offset + tc->count > txq) { 2628 netdev_warn(dev, "Number of in use tx queues changed invalidating tc mappings. Priority traffic classification disabled!\n"); 2629 dev->num_tc = 0; 2630 return; 2631 } 2632 2633 /* Invalidated prio to tc mappings set to TC0 */ 2634 for (i = 1; i < TC_BITMASK + 1; i++) { 2635 int q = netdev_get_prio_tc_map(dev, i); 2636 2637 tc = &dev->tc_to_txq[q]; 2638 if (tc->offset + tc->count > txq) { 2639 netdev_warn(dev, "Number of in use tx queues changed. Priority %i to tc mapping %i is no longer valid. Setting map to 0\n", 2640 i, q); 2641 netdev_set_prio_tc_map(dev, i, 0); 2642 } 2643 } 2644 } 2645 2646 int netdev_txq_to_tc(struct net_device *dev, unsigned int txq) 2647 { 2648 if (dev->num_tc) { 2649 struct netdev_tc_txq *tc = &dev->tc_to_txq[0]; 2650 int i; 2651 2652 /* walk through the TCs and see if it falls into any of them */ 2653 for (i = 0; i < TC_MAX_QUEUE; i++, tc++) { 2654 if ((txq - tc->offset) < tc->count) 2655 return i; 2656 } 2657 2658 /* didn't find it, just return -1 to indicate no match */ 2659 return -1; 2660 } 2661 2662 return 0; 2663 } 2664 EXPORT_SYMBOL(netdev_txq_to_tc); 2665 2666 #ifdef CONFIG_XPS 2667 static struct static_key xps_needed __read_mostly; 2668 static struct static_key xps_rxqs_needed __read_mostly; 2669 static DEFINE_MUTEX(xps_map_mutex); 2670 #define xmap_dereference(P) \ 2671 rcu_dereference_protected((P), lockdep_is_held(&xps_map_mutex)) 2672 2673 static bool remove_xps_queue(struct xps_dev_maps *dev_maps, 2674 struct xps_dev_maps *old_maps, int tci, u16 index) 2675 { 2676 struct xps_map *map = NULL; 2677 int pos; 2678 2679 map = xmap_dereference(dev_maps->attr_map[tci]); 2680 if (!map) 2681 return false; 2682 2683 for (pos = map->len; pos--;) { 2684 if (map->queues[pos] != index) 2685 continue; 2686 2687 if (map->len > 1) { 2688 map->queues[pos] = map->queues[--map->len]; 2689 break; 2690 } 2691 2692 if (old_maps) 2693 RCU_INIT_POINTER(old_maps->attr_map[tci], NULL); 2694 RCU_INIT_POINTER(dev_maps->attr_map[tci], NULL); 2695 kfree_rcu(map, rcu); 2696 return false; 2697 } 2698 2699 return true; 2700 } 2701 2702 static bool remove_xps_queue_cpu(struct net_device *dev, 2703 struct xps_dev_maps *dev_maps, 2704 int cpu, u16 offset, u16 count) 2705 { 2706 int num_tc = dev_maps->num_tc; 2707 bool active = false; 2708 int tci; 2709 2710 for (tci = cpu * num_tc; num_tc--; tci++) { 2711 int i, j; 2712 2713 for (i = count, j = offset; i--; j++) { 2714 if (!remove_xps_queue(dev_maps, NULL, tci, j)) 2715 break; 2716 } 2717 2718 active |= i < 0; 2719 } 2720 2721 return active; 2722 } 2723 2724 static void reset_xps_maps(struct net_device *dev, 2725 struct xps_dev_maps *dev_maps, 2726 enum xps_map_type type) 2727 { 2728 static_key_slow_dec_cpuslocked(&xps_needed); 2729 if (type == XPS_RXQS) 2730 static_key_slow_dec_cpuslocked(&xps_rxqs_needed); 2731 2732 RCU_INIT_POINTER(dev->xps_maps[type], NULL); 2733 2734 kfree_rcu(dev_maps, rcu); 2735 } 2736 2737 static void clean_xps_maps(struct net_device *dev, enum xps_map_type type, 2738 u16 offset, u16 count) 2739 { 2740 struct xps_dev_maps *dev_maps; 2741 bool active = false; 2742 int i, j; 2743 2744 dev_maps = xmap_dereference(dev->xps_maps[type]); 2745 if (!dev_maps) 2746 return; 2747 2748 for (j = 0; j < dev_maps->nr_ids; j++) 2749 active |= remove_xps_queue_cpu(dev, dev_maps, j, offset, count); 2750 if (!active) 2751 reset_xps_maps(dev, dev_maps, type); 2752 2753 if (type == XPS_CPUS) { 2754 for (i = offset + (count - 1); count--; i--) 2755 netdev_queue_numa_node_write( 2756 netdev_get_tx_queue(dev, i), NUMA_NO_NODE); 2757 } 2758 } 2759 2760 static void netif_reset_xps_queues(struct net_device *dev, u16 offset, 2761 u16 count) 2762 { 2763 if (!static_key_false(&xps_needed)) 2764 return; 2765 2766 cpus_read_lock(); 2767 mutex_lock(&xps_map_mutex); 2768 2769 if (static_key_false(&xps_rxqs_needed)) 2770 clean_xps_maps(dev, XPS_RXQS, offset, count); 2771 2772 clean_xps_maps(dev, XPS_CPUS, offset, count); 2773 2774 mutex_unlock(&xps_map_mutex); 2775 cpus_read_unlock(); 2776 } 2777 2778 static void netif_reset_xps_queues_gt(struct net_device *dev, u16 index) 2779 { 2780 netif_reset_xps_queues(dev, index, dev->num_tx_queues - index); 2781 } 2782 2783 static struct xps_map *expand_xps_map(struct xps_map *map, int attr_index, 2784 u16 index, bool is_rxqs_map) 2785 { 2786 struct xps_map *new_map; 2787 int alloc_len = XPS_MIN_MAP_ALLOC; 2788 int i, pos; 2789 2790 for (pos = 0; map && pos < map->len; pos++) { 2791 if (map->queues[pos] != index) 2792 continue; 2793 return map; 2794 } 2795 2796 /* Need to add tx-queue to this CPU's/rx-queue's existing map */ 2797 if (map) { 2798 if (pos < map->alloc_len) 2799 return map; 2800 2801 alloc_len = map->alloc_len * 2; 2802 } 2803 2804 /* Need to allocate new map to store tx-queue on this CPU's/rx-queue's 2805 * map 2806 */ 2807 if (is_rxqs_map) 2808 new_map = kzalloc(XPS_MAP_SIZE(alloc_len), GFP_KERNEL); 2809 else 2810 new_map = kzalloc_node(XPS_MAP_SIZE(alloc_len), GFP_KERNEL, 2811 cpu_to_node(attr_index)); 2812 if (!new_map) 2813 return NULL; 2814 2815 for (i = 0; i < pos; i++) 2816 new_map->queues[i] = map->queues[i]; 2817 new_map->alloc_len = alloc_len; 2818 new_map->len = pos; 2819 2820 return new_map; 2821 } 2822 2823 /* Copy xps maps at a given index */ 2824 static void xps_copy_dev_maps(struct xps_dev_maps *dev_maps, 2825 struct xps_dev_maps *new_dev_maps, int index, 2826 int tc, bool skip_tc) 2827 { 2828 int i, tci = index * dev_maps->num_tc; 2829 struct xps_map *map; 2830 2831 /* copy maps belonging to foreign traffic classes */ 2832 for (i = 0; i < dev_maps->num_tc; i++, tci++) { 2833 if (i == tc && skip_tc) 2834 continue; 2835 2836 /* fill in the new device map from the old device map */ 2837 map = xmap_dereference(dev_maps->attr_map[tci]); 2838 RCU_INIT_POINTER(new_dev_maps->attr_map[tci], map); 2839 } 2840 } 2841 2842 /* Must be called under cpus_read_lock */ 2843 int __netif_set_xps_queue(struct net_device *dev, const unsigned long *mask, 2844 u16 index, enum xps_map_type type) 2845 { 2846 struct xps_dev_maps *dev_maps, *new_dev_maps = NULL, *old_dev_maps = NULL; 2847 const unsigned long *online_mask = NULL; 2848 bool active = false, copy = false; 2849 int i, j, tci, numa_node_id = -2; 2850 int maps_sz, num_tc = 1, tc = 0; 2851 struct xps_map *map, *new_map; 2852 unsigned int nr_ids; 2853 2854 WARN_ON_ONCE(index >= dev->num_tx_queues); 2855 2856 if (dev->num_tc) { 2857 /* Do not allow XPS on subordinate device directly */ 2858 num_tc = dev->num_tc; 2859 if (num_tc < 0) 2860 return -EINVAL; 2861 2862 /* If queue belongs to subordinate dev use its map */ 2863 dev = netdev_get_tx_queue(dev, index)->sb_dev ? : dev; 2864 2865 tc = netdev_txq_to_tc(dev, index); 2866 if (tc < 0) 2867 return -EINVAL; 2868 } 2869 2870 mutex_lock(&xps_map_mutex); 2871 2872 dev_maps = xmap_dereference(dev->xps_maps[type]); 2873 if (type == XPS_RXQS) { 2874 maps_sz = XPS_RXQ_DEV_MAPS_SIZE(num_tc, dev->num_rx_queues); 2875 nr_ids = dev->num_rx_queues; 2876 } else { 2877 maps_sz = XPS_CPU_DEV_MAPS_SIZE(num_tc); 2878 if (num_possible_cpus() > 1) 2879 online_mask = cpumask_bits(cpu_online_mask); 2880 nr_ids = nr_cpu_ids; 2881 } 2882 2883 if (maps_sz < L1_CACHE_BYTES) 2884 maps_sz = L1_CACHE_BYTES; 2885 2886 /* The old dev_maps could be larger or smaller than the one we're 2887 * setting up now, as dev->num_tc or nr_ids could have been updated in 2888 * between. We could try to be smart, but let's be safe instead and only 2889 * copy foreign traffic classes if the two map sizes match. 2890 */ 2891 if (dev_maps && 2892 dev_maps->num_tc == num_tc && dev_maps->nr_ids == nr_ids) 2893 copy = true; 2894 2895 /* allocate memory for queue storage */ 2896 for (j = -1; j = netif_attrmask_next_and(j, online_mask, mask, nr_ids), 2897 j < nr_ids;) { 2898 if (!new_dev_maps) { 2899 new_dev_maps = kzalloc(maps_sz, GFP_KERNEL); 2900 if (!new_dev_maps) { 2901 mutex_unlock(&xps_map_mutex); 2902 return -ENOMEM; 2903 } 2904 2905 new_dev_maps->nr_ids = nr_ids; 2906 new_dev_maps->num_tc = num_tc; 2907 } 2908 2909 tci = j * num_tc + tc; 2910 map = copy ? xmap_dereference(dev_maps->attr_map[tci]) : NULL; 2911 2912 map = expand_xps_map(map, j, index, type == XPS_RXQS); 2913 if (!map) 2914 goto error; 2915 2916 RCU_INIT_POINTER(new_dev_maps->attr_map[tci], map); 2917 } 2918 2919 if (!new_dev_maps) 2920 goto out_no_new_maps; 2921 2922 if (!dev_maps) { 2923 /* Increment static keys at most once per type */ 2924 static_key_slow_inc_cpuslocked(&xps_needed); 2925 if (type == XPS_RXQS) 2926 static_key_slow_inc_cpuslocked(&xps_rxqs_needed); 2927 } 2928 2929 for (j = 0; j < nr_ids; j++) { 2930 bool skip_tc = false; 2931 2932 tci = j * num_tc + tc; 2933 if (netif_attr_test_mask(j, mask, nr_ids) && 2934 netif_attr_test_online(j, online_mask, nr_ids)) { 2935 /* add tx-queue to CPU/rx-queue maps */ 2936 int pos = 0; 2937 2938 skip_tc = true; 2939 2940 map = xmap_dereference(new_dev_maps->attr_map[tci]); 2941 while ((pos < map->len) && (map->queues[pos] != index)) 2942 pos++; 2943 2944 if (pos == map->len) 2945 map->queues[map->len++] = index; 2946 #ifdef CONFIG_NUMA 2947 if (type == XPS_CPUS) { 2948 if (numa_node_id == -2) 2949 numa_node_id = cpu_to_node(j); 2950 else if (numa_node_id != cpu_to_node(j)) 2951 numa_node_id = -1; 2952 } 2953 #endif 2954 } 2955 2956 if (copy) 2957 xps_copy_dev_maps(dev_maps, new_dev_maps, j, tc, 2958 skip_tc); 2959 } 2960 2961 rcu_assign_pointer(dev->xps_maps[type], new_dev_maps); 2962 2963 /* Cleanup old maps */ 2964 if (!dev_maps) 2965 goto out_no_old_maps; 2966 2967 for (j = 0; j < dev_maps->nr_ids; j++) { 2968 for (i = num_tc, tci = j * dev_maps->num_tc; i--; tci++) { 2969 map = xmap_dereference(dev_maps->attr_map[tci]); 2970 if (!map) 2971 continue; 2972 2973 if (copy) { 2974 new_map = xmap_dereference(new_dev_maps->attr_map[tci]); 2975 if (map == new_map) 2976 continue; 2977 } 2978 2979 RCU_INIT_POINTER(dev_maps->attr_map[tci], NULL); 2980 kfree_rcu(map, rcu); 2981 } 2982 } 2983 2984 old_dev_maps = dev_maps; 2985 2986 out_no_old_maps: 2987 dev_maps = new_dev_maps; 2988 active = true; 2989 2990 out_no_new_maps: 2991 if (type == XPS_CPUS) 2992 /* update Tx queue numa node */ 2993 netdev_queue_numa_node_write(netdev_get_tx_queue(dev, index), 2994 (numa_node_id >= 0) ? 2995 numa_node_id : NUMA_NO_NODE); 2996 2997 if (!dev_maps) 2998 goto out_no_maps; 2999 3000 /* removes tx-queue from unused CPUs/rx-queues */ 3001 for (j = 0; j < dev_maps->nr_ids; j++) { 3002 tci = j * dev_maps->num_tc; 3003 3004 for (i = 0; i < dev_maps->num_tc; i++, tci++) { 3005 if (i == tc && 3006 netif_attr_test_mask(j, mask, dev_maps->nr_ids) && 3007 netif_attr_test_online(j, online_mask, dev_maps->nr_ids)) 3008 continue; 3009 3010 active |= remove_xps_queue(dev_maps, 3011 copy ? old_dev_maps : NULL, 3012 tci, index); 3013 } 3014 } 3015 3016 if (old_dev_maps) 3017 kfree_rcu(old_dev_maps, rcu); 3018 3019 /* free map if not active */ 3020 if (!active) 3021 reset_xps_maps(dev, dev_maps, type); 3022 3023 out_no_maps: 3024 mutex_unlock(&xps_map_mutex); 3025 3026 return 0; 3027 error: 3028 /* remove any maps that we added */ 3029 for (j = 0; j < nr_ids; j++) { 3030 for (i = num_tc, tci = j * num_tc; i--; tci++) { 3031 new_map = xmap_dereference(new_dev_maps->attr_map[tci]); 3032 map = copy ? 3033 xmap_dereference(dev_maps->attr_map[tci]) : 3034 NULL; 3035 if (new_map && new_map != map) 3036 kfree(new_map); 3037 } 3038 } 3039 3040 mutex_unlock(&xps_map_mutex); 3041 3042 kfree(new_dev_maps); 3043 return -ENOMEM; 3044 } 3045 EXPORT_SYMBOL_GPL(__netif_set_xps_queue); 3046 3047 int netif_set_xps_queue(struct net_device *dev, const struct cpumask *mask, 3048 u16 index) 3049 { 3050 int ret; 3051 3052 cpus_read_lock(); 3053 ret = __netif_set_xps_queue(dev, cpumask_bits(mask), index, XPS_CPUS); 3054 cpus_read_unlock(); 3055 3056 return ret; 3057 } 3058 EXPORT_SYMBOL(netif_set_xps_queue); 3059 3060 #endif 3061 static void netdev_unbind_all_sb_channels(struct net_device *dev) 3062 { 3063 struct netdev_queue *txq = &dev->_tx[dev->num_tx_queues]; 3064 3065 /* Unbind any subordinate channels */ 3066 while (txq-- != &dev->_tx[0]) { 3067 if (txq->sb_dev) 3068 netdev_unbind_sb_channel(dev, txq->sb_dev); 3069 } 3070 } 3071 3072 void netdev_reset_tc(struct net_device *dev) 3073 { 3074 #ifdef CONFIG_XPS 3075 netif_reset_xps_queues_gt(dev, 0); 3076 #endif 3077 netdev_unbind_all_sb_channels(dev); 3078 3079 /* Reset TC configuration of device */ 3080 dev->num_tc = 0; 3081 memset(dev->tc_to_txq, 0, sizeof(dev->tc_to_txq)); 3082 memset(dev->prio_tc_map, 0, sizeof(dev->prio_tc_map)); 3083 } 3084 EXPORT_SYMBOL(netdev_reset_tc); 3085 3086 int netdev_set_tc_queue(struct net_device *dev, u8 tc, u16 count, u16 offset) 3087 { 3088 if (tc >= dev->num_tc) 3089 return -EINVAL; 3090 3091 #ifdef CONFIG_XPS 3092 netif_reset_xps_queues(dev, offset, count); 3093 #endif 3094 dev->tc_to_txq[tc].count = count; 3095 dev->tc_to_txq[tc].offset = offset; 3096 return 0; 3097 } 3098 EXPORT_SYMBOL(netdev_set_tc_queue); 3099 3100 int netdev_set_num_tc(struct net_device *dev, u8 num_tc) 3101 { 3102 if (num_tc > TC_MAX_QUEUE) 3103 return -EINVAL; 3104 3105 #ifdef CONFIG_XPS 3106 netif_reset_xps_queues_gt(dev, 0); 3107 #endif 3108 netdev_unbind_all_sb_channels(dev); 3109 3110 dev->num_tc = num_tc; 3111 return 0; 3112 } 3113 EXPORT_SYMBOL(netdev_set_num_tc); 3114 3115 void netdev_unbind_sb_channel(struct net_device *dev, 3116 struct net_device *sb_dev) 3117 { 3118 struct netdev_queue *txq = &dev->_tx[dev->num_tx_queues]; 3119 3120 #ifdef CONFIG_XPS 3121 netif_reset_xps_queues_gt(sb_dev, 0); 3122 #endif 3123 memset(sb_dev->tc_to_txq, 0, sizeof(sb_dev->tc_to_txq)); 3124 memset(sb_dev->prio_tc_map, 0, sizeof(sb_dev->prio_tc_map)); 3125 3126 while (txq-- != &dev->_tx[0]) { 3127 if (txq->sb_dev == sb_dev) 3128 txq->sb_dev = NULL; 3129 } 3130 } 3131 EXPORT_SYMBOL(netdev_unbind_sb_channel); 3132 3133 int netdev_bind_sb_channel_queue(struct net_device *dev, 3134 struct net_device *sb_dev, 3135 u8 tc, u16 count, u16 offset) 3136 { 3137 /* Make certain the sb_dev and dev are already configured */ 3138 if (sb_dev->num_tc >= 0 || tc >= dev->num_tc) 3139 return -EINVAL; 3140 3141 /* We cannot hand out queues we don't have */ 3142 if ((offset + count) > dev->real_num_tx_queues) 3143 return -EINVAL; 3144 3145 /* Record the mapping */ 3146 sb_dev->tc_to_txq[tc].count = count; 3147 sb_dev->tc_to_txq[tc].offset = offset; 3148 3149 /* Provide a way for Tx queue to find the tc_to_txq map or 3150 * XPS map for itself. 3151 */ 3152 while (count--) 3153 netdev_get_tx_queue(dev, count + offset)->sb_dev = sb_dev; 3154 3155 return 0; 3156 } 3157 EXPORT_SYMBOL(netdev_bind_sb_channel_queue); 3158 3159 int netdev_set_sb_channel(struct net_device *dev, u16 channel) 3160 { 3161 /* Do not use a multiqueue device to represent a subordinate channel */ 3162 if (netif_is_multiqueue(dev)) 3163 return -ENODEV; 3164 3165 /* We allow channels 1 - 32767 to be used for subordinate channels. 3166 * Channel 0 is meant to be "native" mode and used only to represent 3167 * the main root device. We allow writing 0 to reset the device back 3168 * to normal mode after being used as a subordinate channel. 3169 */ 3170 if (channel > S16_MAX) 3171 return -EINVAL; 3172 3173 dev->num_tc = -channel; 3174 3175 return 0; 3176 } 3177 EXPORT_SYMBOL(netdev_set_sb_channel); 3178 3179 /* 3180 * Routine to help set real_num_tx_queues. To avoid skbs mapped to queues 3181 * greater than real_num_tx_queues stale skbs on the qdisc must be flushed. 3182 */ 3183 int netif_set_real_num_tx_queues(struct net_device *dev, unsigned int txq) 3184 { 3185 bool disabling; 3186 int rc; 3187 3188 disabling = txq < dev->real_num_tx_queues; 3189 3190 if (txq < 1 || txq > dev->num_tx_queues) 3191 return -EINVAL; 3192 3193 if (dev->reg_state == NETREG_REGISTERED || 3194 dev->reg_state == NETREG_UNREGISTERING) { 3195 netdev_ops_assert_locked(dev); 3196 3197 rc = netdev_queue_update_kobjects(dev, dev->real_num_tx_queues, 3198 txq); 3199 if (rc) 3200 return rc; 3201 3202 if (dev->num_tc) 3203 netif_setup_tc(dev, txq); 3204 3205 net_shaper_set_real_num_tx_queues(dev, txq); 3206 3207 dev_qdisc_change_real_num_tx(dev, txq); 3208 3209 dev->real_num_tx_queues = txq; 3210 3211 if (disabling) { 3212 synchronize_net(); 3213 qdisc_reset_all_tx_gt(dev, txq); 3214 #ifdef CONFIG_XPS 3215 netif_reset_xps_queues_gt(dev, txq); 3216 #endif 3217 } 3218 } else { 3219 dev->real_num_tx_queues = txq; 3220 } 3221 3222 return 0; 3223 } 3224 EXPORT_SYMBOL(netif_set_real_num_tx_queues); 3225 3226 /** 3227 * netif_set_real_num_rx_queues - set actual number of RX queues used 3228 * @dev: Network device 3229 * @rxq: Actual number of RX queues 3230 * 3231 * This must be called either with the rtnl_lock held or before 3232 * registration of the net device. Returns 0 on success, or a 3233 * negative error code. If called before registration, it always 3234 * succeeds. 3235 */ 3236 int netif_set_real_num_rx_queues(struct net_device *dev, unsigned int rxq) 3237 { 3238 int rc; 3239 3240 if (rxq < 1 || rxq > dev->num_rx_queues) 3241 return -EINVAL; 3242 3243 if (dev->reg_state == NETREG_REGISTERED) { 3244 netdev_ops_assert_locked(dev); 3245 3246 rc = net_rx_queue_update_kobjects(dev, dev->real_num_rx_queues, 3247 rxq); 3248 if (rc) 3249 return rc; 3250 } 3251 3252 dev->real_num_rx_queues = rxq; 3253 return 0; 3254 } 3255 EXPORT_SYMBOL(netif_set_real_num_rx_queues); 3256 3257 /** 3258 * netif_set_real_num_queues - set actual number of RX and TX queues used 3259 * @dev: Network device 3260 * @txq: Actual number of TX queues 3261 * @rxq: Actual number of RX queues 3262 * 3263 * Set the real number of both TX and RX queues. 3264 * Does nothing if the number of queues is already correct. 3265 */ 3266 int netif_set_real_num_queues(struct net_device *dev, 3267 unsigned int txq, unsigned int rxq) 3268 { 3269 unsigned int old_rxq = dev->real_num_rx_queues; 3270 int err; 3271 3272 if (txq < 1 || txq > dev->num_tx_queues || 3273 rxq < 1 || rxq > dev->num_rx_queues) 3274 return -EINVAL; 3275 3276 /* Start from increases, so the error path only does decreases - 3277 * decreases can't fail. 3278 */ 3279 if (rxq > dev->real_num_rx_queues) { 3280 err = netif_set_real_num_rx_queues(dev, rxq); 3281 if (err) 3282 return err; 3283 } 3284 if (txq > dev->real_num_tx_queues) { 3285 err = netif_set_real_num_tx_queues(dev, txq); 3286 if (err) 3287 goto undo_rx; 3288 } 3289 if (rxq < dev->real_num_rx_queues) 3290 WARN_ON(netif_set_real_num_rx_queues(dev, rxq)); 3291 if (txq < dev->real_num_tx_queues) 3292 WARN_ON(netif_set_real_num_tx_queues(dev, txq)); 3293 3294 return 0; 3295 undo_rx: 3296 WARN_ON(netif_set_real_num_rx_queues(dev, old_rxq)); 3297 return err; 3298 } 3299 EXPORT_SYMBOL(netif_set_real_num_queues); 3300 3301 /** 3302 * netif_set_tso_max_size() - set the max size of TSO frames supported 3303 * @dev: netdev to update 3304 * @size: max skb->len of a TSO frame 3305 * 3306 * Set the limit on the size of TSO super-frames the device can handle. 3307 * Unless explicitly set the stack will assume the value of 3308 * %GSO_LEGACY_MAX_SIZE. 3309 */ 3310 void netif_set_tso_max_size(struct net_device *dev, unsigned int size) 3311 { 3312 dev->tso_max_size = min(GSO_MAX_SIZE, size); 3313 if (size < READ_ONCE(dev->gso_max_size)) 3314 netif_set_gso_max_size(dev, size); 3315 if (size < READ_ONCE(dev->gso_ipv4_max_size)) 3316 netif_set_gso_ipv4_max_size(dev, size); 3317 } 3318 EXPORT_SYMBOL(netif_set_tso_max_size); 3319 3320 /** 3321 * netif_set_tso_max_segs() - set the max number of segs supported for TSO 3322 * @dev: netdev to update 3323 * @segs: max number of TCP segments 3324 * 3325 * Set the limit on the number of TCP segments the device can generate from 3326 * a single TSO super-frame. 3327 * Unless explicitly set the stack will assume the value of %GSO_MAX_SEGS. 3328 */ 3329 void netif_set_tso_max_segs(struct net_device *dev, unsigned int segs) 3330 { 3331 dev->tso_max_segs = segs; 3332 if (segs < READ_ONCE(dev->gso_max_segs)) 3333 netif_set_gso_max_segs(dev, segs); 3334 } 3335 EXPORT_SYMBOL(netif_set_tso_max_segs); 3336 3337 /** 3338 * netif_inherit_tso_max() - copy all TSO limits from a lower device to an upper 3339 * @to: netdev to update 3340 * @from: netdev from which to copy the limits 3341 */ 3342 void netif_inherit_tso_max(struct net_device *to, const struct net_device *from) 3343 { 3344 netif_set_tso_max_size(to, from->tso_max_size); 3345 netif_set_tso_max_segs(to, from->tso_max_segs); 3346 } 3347 EXPORT_SYMBOL(netif_inherit_tso_max); 3348 3349 /** 3350 * netif_get_num_default_rss_queues - default number of RSS queues 3351 * 3352 * Default value is the number of physical cores if there are only 1 or 2, or 3353 * divided by 2 if there are more. 3354 */ 3355 int netif_get_num_default_rss_queues(void) 3356 { 3357 cpumask_var_t cpus; 3358 int cpu, count = 0; 3359 3360 if (unlikely(is_kdump_kernel() || !zalloc_cpumask_var(&cpus, GFP_KERNEL))) 3361 return 1; 3362 3363 cpumask_copy(cpus, cpu_online_mask); 3364 for_each_cpu(cpu, cpus) { 3365 ++count; 3366 cpumask_andnot(cpus, cpus, topology_sibling_cpumask(cpu)); 3367 } 3368 free_cpumask_var(cpus); 3369 3370 return count > 2 ? DIV_ROUND_UP(count, 2) : count; 3371 } 3372 EXPORT_SYMBOL(netif_get_num_default_rss_queues); 3373 3374 static void __netif_reschedule(struct Qdisc *q) 3375 { 3376 struct softnet_data *sd; 3377 unsigned long flags; 3378 3379 local_irq_save(flags); 3380 sd = this_cpu_ptr(&softnet_data); 3381 q->next_sched = NULL; 3382 *sd->output_queue_tailp = q; 3383 sd->output_queue_tailp = &q->next_sched; 3384 raise_softirq_irqoff(NET_TX_SOFTIRQ); 3385 local_irq_restore(flags); 3386 } 3387 3388 void __netif_schedule(struct Qdisc *q) 3389 { 3390 if (!test_and_set_bit(__QDISC_STATE_SCHED, &q->state)) 3391 __netif_reschedule(q); 3392 } 3393 EXPORT_SYMBOL(__netif_schedule); 3394 3395 struct dev_kfree_skb_cb { 3396 enum skb_drop_reason reason; 3397 }; 3398 3399 static struct dev_kfree_skb_cb *get_kfree_skb_cb(const struct sk_buff *skb) 3400 { 3401 return (struct dev_kfree_skb_cb *)skb->cb; 3402 } 3403 3404 void netif_schedule_queue(struct netdev_queue *txq) 3405 { 3406 rcu_read_lock(); 3407 if (!netif_xmit_stopped(txq)) { 3408 struct Qdisc *q = rcu_dereference(txq->qdisc); 3409 3410 __netif_schedule(q); 3411 } 3412 rcu_read_unlock(); 3413 } 3414 EXPORT_SYMBOL(netif_schedule_queue); 3415 3416 void netif_tx_wake_queue(struct netdev_queue *dev_queue) 3417 { 3418 if (test_and_clear_bit(__QUEUE_STATE_DRV_XOFF, &dev_queue->state)) { 3419 struct Qdisc *q; 3420 3421 rcu_read_lock(); 3422 q = rcu_dereference(dev_queue->qdisc); 3423 __netif_schedule(q); 3424 rcu_read_unlock(); 3425 } 3426 } 3427 EXPORT_SYMBOL(netif_tx_wake_queue); 3428 3429 void dev_kfree_skb_irq_reason(struct sk_buff *skb, enum skb_drop_reason reason) 3430 { 3431 unsigned long flags; 3432 3433 if (unlikely(!skb)) 3434 return; 3435 3436 if (likely(refcount_read(&skb->users) == 1)) { 3437 smp_rmb(); 3438 refcount_set(&skb->users, 0); 3439 } else if (likely(!refcount_dec_and_test(&skb->users))) { 3440 return; 3441 } 3442 get_kfree_skb_cb(skb)->reason = reason; 3443 local_irq_save(flags); 3444 skb->next = __this_cpu_read(softnet_data.completion_queue); 3445 __this_cpu_write(softnet_data.completion_queue, skb); 3446 raise_softirq_irqoff(NET_TX_SOFTIRQ); 3447 local_irq_restore(flags); 3448 } 3449 EXPORT_SYMBOL(dev_kfree_skb_irq_reason); 3450 3451 void dev_kfree_skb_any_reason(struct sk_buff *skb, enum skb_drop_reason reason) 3452 { 3453 if (in_hardirq() || irqs_disabled()) 3454 dev_kfree_skb_irq_reason(skb, reason); 3455 else 3456 kfree_skb_reason(skb, reason); 3457 } 3458 EXPORT_SYMBOL(dev_kfree_skb_any_reason); 3459 3460 3461 /** 3462 * netif_device_detach - mark device as removed 3463 * @dev: network device 3464 * 3465 * Mark device as removed from system and therefore no longer available. 3466 */ 3467 void netif_device_detach(struct net_device *dev) 3468 { 3469 if (test_and_clear_bit(__LINK_STATE_PRESENT, &dev->state) && 3470 netif_running(dev)) { 3471 netif_tx_stop_all_queues(dev); 3472 } 3473 } 3474 EXPORT_SYMBOL(netif_device_detach); 3475 3476 /** 3477 * netif_device_attach - mark device as attached 3478 * @dev: network device 3479 * 3480 * Mark device as attached from system and restart if needed. 3481 */ 3482 void netif_device_attach(struct net_device *dev) 3483 { 3484 if (!test_and_set_bit(__LINK_STATE_PRESENT, &dev->state) && 3485 netif_running(dev)) { 3486 netif_tx_wake_all_queues(dev); 3487 netdev_watchdog_up(dev); 3488 } 3489 } 3490 EXPORT_SYMBOL(netif_device_attach); 3491 3492 /* 3493 * Returns a Tx hash based on the given packet descriptor a Tx queues' number 3494 * to be used as a distribution range. 3495 */ 3496 static u16 skb_tx_hash(const struct net_device *dev, 3497 const struct net_device *sb_dev, 3498 struct sk_buff *skb) 3499 { 3500 u32 hash; 3501 u16 qoffset = 0; 3502 u16 qcount = dev->real_num_tx_queues; 3503 3504 if (dev->num_tc) { 3505 u8 tc = netdev_get_prio_tc_map(dev, skb->priority); 3506 3507 qoffset = sb_dev->tc_to_txq[tc].offset; 3508 qcount = sb_dev->tc_to_txq[tc].count; 3509 if (unlikely(!qcount)) { 3510 net_warn_ratelimited("%s: invalid qcount, qoffset %u for tc %u\n", 3511 sb_dev->name, qoffset, tc); 3512 qoffset = 0; 3513 qcount = dev->real_num_tx_queues; 3514 } 3515 } 3516 3517 if (skb_rx_queue_recorded(skb)) { 3518 DEBUG_NET_WARN_ON_ONCE(qcount == 0); 3519 hash = skb_get_rx_queue(skb); 3520 if (hash >= qoffset) 3521 hash -= qoffset; 3522 while (unlikely(hash >= qcount)) 3523 hash -= qcount; 3524 return hash + qoffset; 3525 } 3526 3527 return (u16) reciprocal_scale(skb_get_hash(skb), qcount) + qoffset; 3528 } 3529 3530 void skb_warn_bad_offload(const struct sk_buff *skb) 3531 { 3532 static const netdev_features_t null_features; 3533 struct net_device *dev = skb->dev; 3534 const char *name = ""; 3535 3536 if (!net_ratelimit()) 3537 return; 3538 3539 if (dev) { 3540 if (dev->dev.parent) 3541 name = dev_driver_string(dev->dev.parent); 3542 else 3543 name = netdev_name(dev); 3544 } 3545 skb_dump(KERN_WARNING, skb, false); 3546 WARN(1, "%s: caps=(%pNF, %pNF)\n", 3547 name, dev ? &dev->features : &null_features, 3548 skb->sk ? &skb->sk->sk_route_caps : &null_features); 3549 } 3550 3551 /* 3552 * Invalidate hardware checksum when packet is to be mangled, and 3553 * complete checksum manually on outgoing path. 3554 */ 3555 int skb_checksum_help(struct sk_buff *skb) 3556 { 3557 __wsum csum; 3558 int ret = 0, offset; 3559 3560 if (skb->ip_summed == CHECKSUM_COMPLETE) 3561 goto out_set_summed; 3562 3563 if (unlikely(skb_is_gso(skb))) { 3564 skb_warn_bad_offload(skb); 3565 return -EINVAL; 3566 } 3567 3568 if (!skb_frags_readable(skb)) { 3569 return -EFAULT; 3570 } 3571 3572 /* Before computing a checksum, we should make sure no frag could 3573 * be modified by an external entity : checksum could be wrong. 3574 */ 3575 if (skb_has_shared_frag(skb)) { 3576 ret = __skb_linearize(skb); 3577 if (ret) 3578 goto out; 3579 } 3580 3581 offset = skb_checksum_start_offset(skb); 3582 ret = -EINVAL; 3583 if (unlikely(offset >= skb_headlen(skb))) { 3584 DO_ONCE_LITE(skb_dump, KERN_ERR, skb, false); 3585 WARN_ONCE(true, "offset (%d) >= skb_headlen() (%u)\n", 3586 offset, skb_headlen(skb)); 3587 goto out; 3588 } 3589 csum = skb_checksum(skb, offset, skb->len - offset, 0); 3590 3591 offset += skb->csum_offset; 3592 if (unlikely(offset + sizeof(__sum16) > skb_headlen(skb))) { 3593 DO_ONCE_LITE(skb_dump, KERN_ERR, skb, false); 3594 WARN_ONCE(true, "offset+2 (%zu) > skb_headlen() (%u)\n", 3595 offset + sizeof(__sum16), skb_headlen(skb)); 3596 goto out; 3597 } 3598 ret = skb_ensure_writable(skb, offset + sizeof(__sum16)); 3599 if (ret) 3600 goto out; 3601 3602 *(__sum16 *)(skb->data + offset) = csum_fold(csum) ?: CSUM_MANGLED_0; 3603 out_set_summed: 3604 skb->ip_summed = CHECKSUM_NONE; 3605 out: 3606 return ret; 3607 } 3608 EXPORT_SYMBOL(skb_checksum_help); 3609 3610 #ifdef CONFIG_NET_CRC32C 3611 int skb_crc32c_csum_help(struct sk_buff *skb) 3612 { 3613 u32 crc; 3614 int ret = 0, offset, start; 3615 3616 if (skb->ip_summed != CHECKSUM_PARTIAL) 3617 goto out; 3618 3619 if (unlikely(skb_is_gso(skb))) 3620 goto out; 3621 3622 /* Before computing a checksum, we should make sure no frag could 3623 * be modified by an external entity : checksum could be wrong. 3624 */ 3625 if (unlikely(skb_has_shared_frag(skb))) { 3626 ret = __skb_linearize(skb); 3627 if (ret) 3628 goto out; 3629 } 3630 start = skb_checksum_start_offset(skb); 3631 offset = start + offsetof(struct sctphdr, checksum); 3632 if (WARN_ON_ONCE(offset >= skb_headlen(skb))) { 3633 ret = -EINVAL; 3634 goto out; 3635 } 3636 3637 ret = skb_ensure_writable(skb, offset + sizeof(__le32)); 3638 if (ret) 3639 goto out; 3640 3641 crc = ~skb_crc32c(skb, start, skb->len - start, ~0); 3642 *(__le32 *)(skb->data + offset) = cpu_to_le32(crc); 3643 skb_reset_csum_not_inet(skb); 3644 out: 3645 return ret; 3646 } 3647 EXPORT_SYMBOL(skb_crc32c_csum_help); 3648 #endif /* CONFIG_NET_CRC32C */ 3649 3650 __be16 skb_network_protocol(struct sk_buff *skb, int *depth) 3651 { 3652 __be16 type = skb->protocol; 3653 3654 /* Tunnel gso handlers can set protocol to ethernet. */ 3655 if (type == htons(ETH_P_TEB)) { 3656 struct ethhdr *eth; 3657 3658 if (unlikely(!pskb_may_pull(skb, sizeof(struct ethhdr)))) 3659 return 0; 3660 3661 eth = (struct ethhdr *)skb->data; 3662 type = eth->h_proto; 3663 } 3664 3665 return vlan_get_protocol_and_depth(skb, type, depth); 3666 } 3667 3668 3669 /* Take action when hardware reception checksum errors are detected. */ 3670 #ifdef CONFIG_BUG 3671 static void do_netdev_rx_csum_fault(struct net_device *dev, struct sk_buff *skb) 3672 { 3673 netdev_err(dev, "hw csum failure\n"); 3674 skb_dump(KERN_ERR, skb, true); 3675 dump_stack(); 3676 } 3677 3678 void netdev_rx_csum_fault(struct net_device *dev, struct sk_buff *skb) 3679 { 3680 DO_ONCE_LITE(do_netdev_rx_csum_fault, dev, skb); 3681 } 3682 EXPORT_SYMBOL(netdev_rx_csum_fault); 3683 #endif 3684 3685 /* XXX: check that highmem exists at all on the given machine. */ 3686 static int illegal_highdma(struct net_device *dev, struct sk_buff *skb) 3687 { 3688 #ifdef CONFIG_HIGHMEM 3689 int i; 3690 3691 if (!(dev->features & NETIF_F_HIGHDMA)) { 3692 for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) { 3693 skb_frag_t *frag = &skb_shinfo(skb)->frags[i]; 3694 struct page *page = skb_frag_page(frag); 3695 3696 if (page && PageHighMem(page)) 3697 return 1; 3698 } 3699 } 3700 #endif 3701 return 0; 3702 } 3703 3704 /* If MPLS offload request, verify we are testing hardware MPLS features 3705 * instead of standard features for the netdev. 3706 */ 3707 #if IS_ENABLED(CONFIG_NET_MPLS_GSO) 3708 static netdev_features_t net_mpls_features(struct sk_buff *skb, 3709 netdev_features_t features, 3710 __be16 type) 3711 { 3712 if (eth_p_mpls(type)) 3713 features &= skb->dev->mpls_features; 3714 3715 return features; 3716 } 3717 #else 3718 static netdev_features_t net_mpls_features(struct sk_buff *skb, 3719 netdev_features_t features, 3720 __be16 type) 3721 { 3722 return features; 3723 } 3724 #endif 3725 3726 static netdev_features_t harmonize_features(struct sk_buff *skb, 3727 netdev_features_t features) 3728 { 3729 __be16 type; 3730 3731 type = skb_network_protocol(skb, NULL); 3732 features = net_mpls_features(skb, features, type); 3733 3734 if (skb->ip_summed != CHECKSUM_NONE && 3735 !can_checksum_protocol(features, type)) { 3736 features &= ~(NETIF_F_CSUM_MASK | NETIF_F_GSO_MASK); 3737 } 3738 if (illegal_highdma(skb->dev, skb)) 3739 features &= ~NETIF_F_SG; 3740 3741 return features; 3742 } 3743 3744 netdev_features_t passthru_features_check(struct sk_buff *skb, 3745 struct net_device *dev, 3746 netdev_features_t features) 3747 { 3748 return features; 3749 } 3750 EXPORT_SYMBOL(passthru_features_check); 3751 3752 static netdev_features_t dflt_features_check(struct sk_buff *skb, 3753 struct net_device *dev, 3754 netdev_features_t features) 3755 { 3756 return vlan_features_check(skb, features); 3757 } 3758 3759 static bool skb_gso_has_extension_hdr(const struct sk_buff *skb) 3760 { 3761 if (!skb->encapsulation) 3762 return ((skb_shinfo(skb)->gso_type & SKB_GSO_TCPV6 || 3763 (skb_shinfo(skb)->gso_type & SKB_GSO_UDP_L4 && 3764 vlan_get_protocol(skb) == htons(ETH_P_IPV6))) && 3765 skb_transport_header_was_set(skb) && 3766 skb_network_header_len(skb) != sizeof(struct ipv6hdr)); 3767 else 3768 return (!skb_inner_network_header_was_set(skb) || 3769 ((skb_shinfo(skb)->gso_type & SKB_GSO_TCPV6 || 3770 (skb_shinfo(skb)->gso_type & SKB_GSO_UDP_L4 && 3771 inner_ip_hdr(skb)->version == 6)) && 3772 skb_inner_network_header_len(skb) != sizeof(struct ipv6hdr))); 3773 } 3774 3775 static netdev_features_t gso_features_check(const struct sk_buff *skb, 3776 struct net_device *dev, 3777 netdev_features_t features) 3778 { 3779 u16 gso_segs = skb_shinfo(skb)->gso_segs; 3780 3781 if (gso_segs > READ_ONCE(dev->gso_max_segs)) 3782 return features & ~NETIF_F_GSO_MASK; 3783 3784 if (unlikely(skb->len >= netif_get_gso_max_size(dev, skb))) 3785 return features & ~NETIF_F_GSO_MASK; 3786 3787 if (!skb_shinfo(skb)->gso_type) { 3788 skb_warn_bad_offload(skb); 3789 return features & ~NETIF_F_GSO_MASK; 3790 } 3791 3792 /* Support for GSO partial features requires software 3793 * intervention before we can actually process the packets 3794 * so we need to strip support for any partial features now 3795 * and we can pull them back in after we have partially 3796 * segmented the frame. 3797 */ 3798 if (!(skb_shinfo(skb)->gso_type & SKB_GSO_PARTIAL)) 3799 features &= ~dev->gso_partial_features; 3800 3801 /* Make sure to clear the IPv4 ID mangling feature if the IPv4 header 3802 * has the potential to be fragmented so that TSO does not generate 3803 * segments with the same ID. For encapsulated packets, the ID mangling 3804 * feature is guaranteed not to use the same ID for the outer IPv4 3805 * headers of the generated segments if the headers have the potential 3806 * to be fragmented, so there is no need to clear the IPv4 ID mangling 3807 * feature (see the section about NETIF_F_TSO_MANGLEID in 3808 * segmentation-offloads.rst). 3809 */ 3810 if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV4) { 3811 const struct iphdr *iph; 3812 struct iphdr _iph; 3813 int nhoff = skb->encapsulation ? 3814 skb_inner_network_offset(skb) : 3815 skb_network_offset(skb); 3816 3817 iph = skb_header_pointer(skb, nhoff, sizeof(_iph), &_iph); 3818 3819 if (!iph || !(iph->frag_off & htons(IP_DF))) 3820 features &= ~dev->mangleid_features; 3821 } 3822 3823 /* NETIF_F_IPV6_CSUM does not support IPv6 extension headers, 3824 * so neither does TSO that depends on it. 3825 */ 3826 if (features & NETIF_F_IPV6_CSUM && 3827 skb_gso_has_extension_hdr(skb) && 3828 !ipv6_has_hopopt_jumbo(skb)) 3829 features &= ~(NETIF_F_IPV6_CSUM | NETIF_F_TSO6 | NETIF_F_GSO_UDP_L4); 3830 3831 return features; 3832 } 3833 3834 netdev_features_t netif_skb_features(struct sk_buff *skb) 3835 { 3836 struct net_device *dev = skb->dev; 3837 netdev_features_t features = dev->features; 3838 3839 if (skb_is_gso(skb)) 3840 features = gso_features_check(skb, dev, features); 3841 3842 /* If encapsulation offload request, verify we are testing 3843 * hardware encapsulation features instead of standard 3844 * features for the netdev 3845 */ 3846 if (skb->encapsulation) 3847 features &= dev->hw_enc_features; 3848 3849 if (skb_vlan_tagged(skb)) 3850 features = netdev_intersect_features(features, 3851 dev->vlan_features | 3852 NETIF_F_HW_VLAN_CTAG_TX | 3853 NETIF_F_HW_VLAN_STAG_TX); 3854 3855 if (dev->netdev_ops->ndo_features_check) 3856 features &= dev->netdev_ops->ndo_features_check(skb, dev, 3857 features); 3858 else 3859 features &= dflt_features_check(skb, dev, features); 3860 3861 return harmonize_features(skb, features); 3862 } 3863 EXPORT_SYMBOL(netif_skb_features); 3864 3865 static int xmit_one(struct sk_buff *skb, struct net_device *dev, 3866 struct netdev_queue *txq, bool more) 3867 { 3868 unsigned int len; 3869 int rc; 3870 3871 if (dev_nit_active_rcu(dev)) 3872 dev_queue_xmit_nit(skb, dev); 3873 3874 len = skb->len; 3875 trace_net_dev_start_xmit(skb, dev); 3876 rc = netdev_start_xmit(skb, dev, txq, more); 3877 trace_net_dev_xmit(skb, rc, dev, len); 3878 3879 return rc; 3880 } 3881 3882 struct sk_buff *dev_hard_start_xmit(struct sk_buff *first, struct net_device *dev, 3883 struct netdev_queue *txq, int *ret) 3884 { 3885 struct sk_buff *skb = first; 3886 int rc = NETDEV_TX_OK; 3887 3888 while (skb) { 3889 struct sk_buff *next = skb->next; 3890 3891 skb_mark_not_on_list(skb); 3892 rc = xmit_one(skb, dev, txq, next != NULL); 3893 if (unlikely(!dev_xmit_complete(rc))) { 3894 skb->next = next; 3895 goto out; 3896 } 3897 3898 skb = next; 3899 if (netif_tx_queue_stopped(txq) && skb) { 3900 rc = NETDEV_TX_BUSY; 3901 break; 3902 } 3903 } 3904 3905 out: 3906 *ret = rc; 3907 return skb; 3908 } 3909 3910 static struct sk_buff *validate_xmit_vlan(struct sk_buff *skb, 3911 netdev_features_t features) 3912 { 3913 if (skb_vlan_tag_present(skb) && 3914 !vlan_hw_offload_capable(features, skb->vlan_proto)) 3915 skb = __vlan_hwaccel_push_inside(skb); 3916 return skb; 3917 } 3918 3919 int skb_csum_hwoffload_help(struct sk_buff *skb, 3920 const netdev_features_t features) 3921 { 3922 if (unlikely(skb_csum_is_sctp(skb))) 3923 return !!(features & NETIF_F_SCTP_CRC) ? 0 : 3924 skb_crc32c_csum_help(skb); 3925 3926 if (features & NETIF_F_HW_CSUM) 3927 return 0; 3928 3929 if (features & (NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM)) { 3930 if (vlan_get_protocol(skb) == htons(ETH_P_IPV6) && 3931 skb_network_header_len(skb) != sizeof(struct ipv6hdr) && 3932 !ipv6_has_hopopt_jumbo(skb)) 3933 goto sw_checksum; 3934 3935 switch (skb->csum_offset) { 3936 case offsetof(struct tcphdr, check): 3937 case offsetof(struct udphdr, check): 3938 return 0; 3939 } 3940 } 3941 3942 sw_checksum: 3943 return skb_checksum_help(skb); 3944 } 3945 EXPORT_SYMBOL(skb_csum_hwoffload_help); 3946 3947 /* Checks if this SKB belongs to an HW offloaded socket 3948 * and whether any SW fallbacks are required based on dev. 3949 * Check decrypted mark in case skb_orphan() cleared socket. 3950 */ 3951 static struct sk_buff *sk_validate_xmit_skb(struct sk_buff *skb, 3952 struct net_device *dev) 3953 { 3954 #ifdef CONFIG_SOCK_VALIDATE_XMIT 3955 struct sk_buff *(*sk_validate)(struct sock *sk, struct net_device *dev, 3956 struct sk_buff *skb); 3957 struct sock *sk = skb->sk; 3958 3959 sk_validate = NULL; 3960 if (sk) { 3961 if (sk_fullsock(sk)) 3962 sk_validate = sk->sk_validate_xmit_skb; 3963 else if (sk_is_inet(sk) && sk->sk_state == TCP_TIME_WAIT) 3964 sk_validate = inet_twsk(sk)->tw_validate_xmit_skb; 3965 } 3966 3967 if (sk_validate) { 3968 skb = sk_validate(sk, dev, skb); 3969 } else if (unlikely(skb_is_decrypted(skb))) { 3970 pr_warn_ratelimited("unencrypted skb with no associated socket - dropping\n"); 3971 kfree_skb(skb); 3972 skb = NULL; 3973 } 3974 #endif 3975 3976 return skb; 3977 } 3978 3979 static struct sk_buff *validate_xmit_unreadable_skb(struct sk_buff *skb, 3980 struct net_device *dev) 3981 { 3982 struct skb_shared_info *shinfo; 3983 struct net_iov *niov; 3984 3985 if (likely(skb_frags_readable(skb))) 3986 goto out; 3987 3988 if (!dev->netmem_tx) 3989 goto out_free; 3990 3991 shinfo = skb_shinfo(skb); 3992 3993 if (shinfo->nr_frags > 0) { 3994 niov = netmem_to_net_iov(skb_frag_netmem(&shinfo->frags[0])); 3995 if (net_is_devmem_iov(niov) && 3996 READ_ONCE(net_devmem_iov_binding(niov)->dev) != dev) 3997 goto out_free; 3998 } 3999 4000 out: 4001 return skb; 4002 4003 out_free: 4004 kfree_skb(skb); 4005 return NULL; 4006 } 4007 4008 static struct sk_buff *validate_xmit_skb(struct sk_buff *skb, struct net_device *dev, bool *again) 4009 { 4010 netdev_features_t features; 4011 4012 skb = validate_xmit_unreadable_skb(skb, dev); 4013 if (unlikely(!skb)) 4014 goto out_null; 4015 4016 features = netif_skb_features(skb); 4017 skb = validate_xmit_vlan(skb, features); 4018 if (unlikely(!skb)) 4019 goto out_null; 4020 4021 skb = sk_validate_xmit_skb(skb, dev); 4022 if (unlikely(!skb)) 4023 goto out_null; 4024 4025 if (netif_needs_gso(skb, features)) { 4026 struct sk_buff *segs; 4027 4028 segs = skb_gso_segment(skb, features); 4029 if (IS_ERR(segs)) { 4030 goto out_kfree_skb; 4031 } else if (segs) { 4032 consume_skb(skb); 4033 skb = segs; 4034 } 4035 } else { 4036 if (skb_needs_linearize(skb, features) && 4037 __skb_linearize(skb)) 4038 goto out_kfree_skb; 4039 4040 /* If packet is not checksummed and device does not 4041 * support checksumming for this protocol, complete 4042 * checksumming here. 4043 */ 4044 if (skb->ip_summed == CHECKSUM_PARTIAL) { 4045 if (skb->encapsulation) 4046 skb_set_inner_transport_header(skb, 4047 skb_checksum_start_offset(skb)); 4048 else 4049 skb_set_transport_header(skb, 4050 skb_checksum_start_offset(skb)); 4051 if (skb_csum_hwoffload_help(skb, features)) 4052 goto out_kfree_skb; 4053 } 4054 } 4055 4056 skb = validate_xmit_xfrm(skb, features, again); 4057 4058 return skb; 4059 4060 out_kfree_skb: 4061 kfree_skb(skb); 4062 out_null: 4063 dev_core_stats_tx_dropped_inc(dev); 4064 return NULL; 4065 } 4066 4067 struct sk_buff *validate_xmit_skb_list(struct sk_buff *skb, struct net_device *dev, bool *again) 4068 { 4069 struct sk_buff *next, *head = NULL, *tail; 4070 4071 for (; skb != NULL; skb = next) { 4072 next = skb->next; 4073 skb_mark_not_on_list(skb); 4074 4075 /* in case skb won't be segmented, point to itself */ 4076 skb->prev = skb; 4077 4078 skb = validate_xmit_skb(skb, dev, again); 4079 if (!skb) 4080 continue; 4081 4082 if (!head) 4083 head = skb; 4084 else 4085 tail->next = skb; 4086 /* If skb was segmented, skb->prev points to 4087 * the last segment. If not, it still contains skb. 4088 */ 4089 tail = skb->prev; 4090 } 4091 return head; 4092 } 4093 EXPORT_SYMBOL_GPL(validate_xmit_skb_list); 4094 4095 static void qdisc_pkt_len_init(struct sk_buff *skb) 4096 { 4097 const struct skb_shared_info *shinfo = skb_shinfo(skb); 4098 4099 qdisc_skb_cb(skb)->pkt_len = skb->len; 4100 4101 /* To get more precise estimation of bytes sent on wire, 4102 * we add to pkt_len the headers size of all segments 4103 */ 4104 if (shinfo->gso_size && skb_transport_header_was_set(skb)) { 4105 u16 gso_segs = shinfo->gso_segs; 4106 unsigned int hdr_len; 4107 4108 /* mac layer + network layer */ 4109 if (!skb->encapsulation) 4110 hdr_len = skb_transport_offset(skb); 4111 else 4112 hdr_len = skb_inner_transport_offset(skb); 4113 4114 /* + transport layer */ 4115 if (likely(shinfo->gso_type & (SKB_GSO_TCPV4 | SKB_GSO_TCPV6))) { 4116 const struct tcphdr *th; 4117 struct tcphdr _tcphdr; 4118 4119 th = skb_header_pointer(skb, hdr_len, 4120 sizeof(_tcphdr), &_tcphdr); 4121 if (likely(th)) 4122 hdr_len += __tcp_hdrlen(th); 4123 } else if (shinfo->gso_type & SKB_GSO_UDP_L4) { 4124 struct udphdr _udphdr; 4125 4126 if (skb_header_pointer(skb, hdr_len, 4127 sizeof(_udphdr), &_udphdr)) 4128 hdr_len += sizeof(struct udphdr); 4129 } 4130 4131 if (unlikely(shinfo->gso_type & SKB_GSO_DODGY)) { 4132 int payload = skb->len - hdr_len; 4133 4134 /* Malicious packet. */ 4135 if (payload <= 0) 4136 return; 4137 gso_segs = DIV_ROUND_UP(payload, shinfo->gso_size); 4138 } 4139 qdisc_skb_cb(skb)->pkt_len += (gso_segs - 1) * hdr_len; 4140 } 4141 } 4142 4143 static int dev_qdisc_enqueue(struct sk_buff *skb, struct Qdisc *q, 4144 struct sk_buff **to_free, 4145 struct netdev_queue *txq) 4146 { 4147 int rc; 4148 4149 rc = q->enqueue(skb, q, to_free) & NET_XMIT_MASK; 4150 if (rc == NET_XMIT_SUCCESS) 4151 trace_qdisc_enqueue(q, txq, skb); 4152 return rc; 4153 } 4154 4155 static inline int __dev_xmit_skb(struct sk_buff *skb, struct Qdisc *q, 4156 struct net_device *dev, 4157 struct netdev_queue *txq) 4158 { 4159 spinlock_t *root_lock = qdisc_lock(q); 4160 struct sk_buff *to_free = NULL; 4161 bool contended; 4162 int rc; 4163 4164 qdisc_calculate_pkt_len(skb, q); 4165 4166 tcf_set_drop_reason(skb, SKB_DROP_REASON_QDISC_DROP); 4167 4168 if (q->flags & TCQ_F_NOLOCK) { 4169 if (q->flags & TCQ_F_CAN_BYPASS && nolock_qdisc_is_empty(q) && 4170 qdisc_run_begin(q)) { 4171 /* Retest nolock_qdisc_is_empty() within the protection 4172 * of q->seqlock to protect from racing with requeuing. 4173 */ 4174 if (unlikely(!nolock_qdisc_is_empty(q))) { 4175 rc = dev_qdisc_enqueue(skb, q, &to_free, txq); 4176 __qdisc_run(q); 4177 qdisc_run_end(q); 4178 4179 goto no_lock_out; 4180 } 4181 4182 qdisc_bstats_cpu_update(q, skb); 4183 if (sch_direct_xmit(skb, q, dev, txq, NULL, true) && 4184 !nolock_qdisc_is_empty(q)) 4185 __qdisc_run(q); 4186 4187 qdisc_run_end(q); 4188 return NET_XMIT_SUCCESS; 4189 } 4190 4191 rc = dev_qdisc_enqueue(skb, q, &to_free, txq); 4192 qdisc_run(q); 4193 4194 no_lock_out: 4195 if (unlikely(to_free)) 4196 kfree_skb_list_reason(to_free, 4197 tcf_get_drop_reason(to_free)); 4198 return rc; 4199 } 4200 4201 if (unlikely(READ_ONCE(q->owner) == smp_processor_id())) { 4202 kfree_skb_reason(skb, SKB_DROP_REASON_TC_RECLASSIFY_LOOP); 4203 return NET_XMIT_DROP; 4204 } 4205 /* 4206 * Heuristic to force contended enqueues to serialize on a 4207 * separate lock before trying to get qdisc main lock. 4208 * This permits qdisc->running owner to get the lock more 4209 * often and dequeue packets faster. 4210 * On PREEMPT_RT it is possible to preempt the qdisc owner during xmit 4211 * and then other tasks will only enqueue packets. The packets will be 4212 * sent after the qdisc owner is scheduled again. To prevent this 4213 * scenario the task always serialize on the lock. 4214 */ 4215 contended = qdisc_is_running(q) || IS_ENABLED(CONFIG_PREEMPT_RT); 4216 if (unlikely(contended)) 4217 spin_lock(&q->busylock); 4218 4219 spin_lock(root_lock); 4220 if (unlikely(test_bit(__QDISC_STATE_DEACTIVATED, &q->state))) { 4221 __qdisc_drop(skb, &to_free); 4222 rc = NET_XMIT_DROP; 4223 } else if ((q->flags & TCQ_F_CAN_BYPASS) && !qdisc_qlen(q) && 4224 qdisc_run_begin(q)) { 4225 /* 4226 * This is a work-conserving queue; there are no old skbs 4227 * waiting to be sent out; and the qdisc is not running - 4228 * xmit the skb directly. 4229 */ 4230 4231 qdisc_bstats_update(q, skb); 4232 4233 if (sch_direct_xmit(skb, q, dev, txq, root_lock, true)) { 4234 if (unlikely(contended)) { 4235 spin_unlock(&q->busylock); 4236 contended = false; 4237 } 4238 __qdisc_run(q); 4239 } 4240 4241 qdisc_run_end(q); 4242 rc = NET_XMIT_SUCCESS; 4243 } else { 4244 WRITE_ONCE(q->owner, smp_processor_id()); 4245 rc = dev_qdisc_enqueue(skb, q, &to_free, txq); 4246 WRITE_ONCE(q->owner, -1); 4247 if (qdisc_run_begin(q)) { 4248 if (unlikely(contended)) { 4249 spin_unlock(&q->busylock); 4250 contended = false; 4251 } 4252 __qdisc_run(q); 4253 qdisc_run_end(q); 4254 } 4255 } 4256 spin_unlock(root_lock); 4257 if (unlikely(to_free)) 4258 kfree_skb_list_reason(to_free, 4259 tcf_get_drop_reason(to_free)); 4260 if (unlikely(contended)) 4261 spin_unlock(&q->busylock); 4262 return rc; 4263 } 4264 4265 #if IS_ENABLED(CONFIG_CGROUP_NET_PRIO) 4266 static void skb_update_prio(struct sk_buff *skb) 4267 { 4268 const struct netprio_map *map; 4269 const struct sock *sk; 4270 unsigned int prioidx; 4271 4272 if (skb->priority) 4273 return; 4274 map = rcu_dereference_bh(skb->dev->priomap); 4275 if (!map) 4276 return; 4277 sk = skb_to_full_sk(skb); 4278 if (!sk) 4279 return; 4280 4281 prioidx = sock_cgroup_prioidx(&sk->sk_cgrp_data); 4282 4283 if (prioidx < map->priomap_len) 4284 skb->priority = map->priomap[prioidx]; 4285 } 4286 #else 4287 #define skb_update_prio(skb) 4288 #endif 4289 4290 /** 4291 * dev_loopback_xmit - loop back @skb 4292 * @net: network namespace this loopback is happening in 4293 * @sk: sk needed to be a netfilter okfn 4294 * @skb: buffer to transmit 4295 */ 4296 int dev_loopback_xmit(struct net *net, struct sock *sk, struct sk_buff *skb) 4297 { 4298 skb_reset_mac_header(skb); 4299 __skb_pull(skb, skb_network_offset(skb)); 4300 skb->pkt_type = PACKET_LOOPBACK; 4301 if (skb->ip_summed == CHECKSUM_NONE) 4302 skb->ip_summed = CHECKSUM_UNNECESSARY; 4303 DEBUG_NET_WARN_ON_ONCE(!skb_dst(skb)); 4304 skb_dst_force(skb); 4305 netif_rx(skb); 4306 return 0; 4307 } 4308 EXPORT_SYMBOL(dev_loopback_xmit); 4309 4310 #ifdef CONFIG_NET_EGRESS 4311 static struct netdev_queue * 4312 netdev_tx_queue_mapping(struct net_device *dev, struct sk_buff *skb) 4313 { 4314 int qm = skb_get_queue_mapping(skb); 4315 4316 return netdev_get_tx_queue(dev, netdev_cap_txqueue(dev, qm)); 4317 } 4318 4319 #ifndef CONFIG_PREEMPT_RT 4320 static bool netdev_xmit_txqueue_skipped(void) 4321 { 4322 return __this_cpu_read(softnet_data.xmit.skip_txqueue); 4323 } 4324 4325 void netdev_xmit_skip_txqueue(bool skip) 4326 { 4327 __this_cpu_write(softnet_data.xmit.skip_txqueue, skip); 4328 } 4329 EXPORT_SYMBOL_GPL(netdev_xmit_skip_txqueue); 4330 4331 #else 4332 static bool netdev_xmit_txqueue_skipped(void) 4333 { 4334 return current->net_xmit.skip_txqueue; 4335 } 4336 4337 void netdev_xmit_skip_txqueue(bool skip) 4338 { 4339 current->net_xmit.skip_txqueue = skip; 4340 } 4341 EXPORT_SYMBOL_GPL(netdev_xmit_skip_txqueue); 4342 #endif 4343 #endif /* CONFIG_NET_EGRESS */ 4344 4345 #ifdef CONFIG_NET_XGRESS 4346 static int tc_run(struct tcx_entry *entry, struct sk_buff *skb, 4347 enum skb_drop_reason *drop_reason) 4348 { 4349 int ret = TC_ACT_UNSPEC; 4350 #ifdef CONFIG_NET_CLS_ACT 4351 struct mini_Qdisc *miniq = rcu_dereference_bh(entry->miniq); 4352 struct tcf_result res; 4353 4354 if (!miniq) 4355 return ret; 4356 4357 /* Global bypass */ 4358 if (!static_branch_likely(&tcf_sw_enabled_key)) 4359 return ret; 4360 4361 /* Block-wise bypass */ 4362 if (tcf_block_bypass_sw(miniq->block)) 4363 return ret; 4364 4365 tc_skb_cb(skb)->mru = 0; 4366 tc_skb_cb(skb)->post_ct = false; 4367 tcf_set_drop_reason(skb, *drop_reason); 4368 4369 mini_qdisc_bstats_cpu_update(miniq, skb); 4370 ret = tcf_classify(skb, miniq->block, miniq->filter_list, &res, false); 4371 /* Only tcf related quirks below. */ 4372 switch (ret) { 4373 case TC_ACT_SHOT: 4374 *drop_reason = tcf_get_drop_reason(skb); 4375 mini_qdisc_qstats_cpu_drop(miniq); 4376 break; 4377 case TC_ACT_OK: 4378 case TC_ACT_RECLASSIFY: 4379 skb->tc_index = TC_H_MIN(res.classid); 4380 break; 4381 } 4382 #endif /* CONFIG_NET_CLS_ACT */ 4383 return ret; 4384 } 4385 4386 static DEFINE_STATIC_KEY_FALSE(tcx_needed_key); 4387 4388 void tcx_inc(void) 4389 { 4390 static_branch_inc(&tcx_needed_key); 4391 } 4392 4393 void tcx_dec(void) 4394 { 4395 static_branch_dec(&tcx_needed_key); 4396 } 4397 4398 static __always_inline enum tcx_action_base 4399 tcx_run(const struct bpf_mprog_entry *entry, struct sk_buff *skb, 4400 const bool needs_mac) 4401 { 4402 const struct bpf_mprog_fp *fp; 4403 const struct bpf_prog *prog; 4404 int ret = TCX_NEXT; 4405 4406 if (needs_mac) 4407 __skb_push(skb, skb->mac_len); 4408 bpf_mprog_foreach_prog(entry, fp, prog) { 4409 bpf_compute_data_pointers(skb); 4410 ret = bpf_prog_run(prog, skb); 4411 if (ret != TCX_NEXT) 4412 break; 4413 } 4414 if (needs_mac) 4415 __skb_pull(skb, skb->mac_len); 4416 return tcx_action_code(skb, ret); 4417 } 4418 4419 static __always_inline struct sk_buff * 4420 sch_handle_ingress(struct sk_buff *skb, struct packet_type **pt_prev, int *ret, 4421 struct net_device *orig_dev, bool *another) 4422 { 4423 struct bpf_mprog_entry *entry = rcu_dereference_bh(skb->dev->tcx_ingress); 4424 enum skb_drop_reason drop_reason = SKB_DROP_REASON_TC_INGRESS; 4425 struct bpf_net_context __bpf_net_ctx, *bpf_net_ctx; 4426 int sch_ret; 4427 4428 if (!entry) 4429 return skb; 4430 4431 bpf_net_ctx = bpf_net_ctx_set(&__bpf_net_ctx); 4432 if (*pt_prev) { 4433 *ret = deliver_skb(skb, *pt_prev, orig_dev); 4434 *pt_prev = NULL; 4435 } 4436 4437 qdisc_skb_cb(skb)->pkt_len = skb->len; 4438 tcx_set_ingress(skb, true); 4439 4440 if (static_branch_unlikely(&tcx_needed_key)) { 4441 sch_ret = tcx_run(entry, skb, true); 4442 if (sch_ret != TC_ACT_UNSPEC) 4443 goto ingress_verdict; 4444 } 4445 sch_ret = tc_run(tcx_entry(entry), skb, &drop_reason); 4446 ingress_verdict: 4447 switch (sch_ret) { 4448 case TC_ACT_REDIRECT: 4449 /* skb_mac_header check was done by BPF, so we can safely 4450 * push the L2 header back before redirecting to another 4451 * netdev. 4452 */ 4453 __skb_push(skb, skb->mac_len); 4454 if (skb_do_redirect(skb) == -EAGAIN) { 4455 __skb_pull(skb, skb->mac_len); 4456 *another = true; 4457 break; 4458 } 4459 *ret = NET_RX_SUCCESS; 4460 bpf_net_ctx_clear(bpf_net_ctx); 4461 return NULL; 4462 case TC_ACT_SHOT: 4463 kfree_skb_reason(skb, drop_reason); 4464 *ret = NET_RX_DROP; 4465 bpf_net_ctx_clear(bpf_net_ctx); 4466 return NULL; 4467 /* used by tc_run */ 4468 case TC_ACT_STOLEN: 4469 case TC_ACT_QUEUED: 4470 case TC_ACT_TRAP: 4471 consume_skb(skb); 4472 fallthrough; 4473 case TC_ACT_CONSUMED: 4474 *ret = NET_RX_SUCCESS; 4475 bpf_net_ctx_clear(bpf_net_ctx); 4476 return NULL; 4477 } 4478 bpf_net_ctx_clear(bpf_net_ctx); 4479 4480 return skb; 4481 } 4482 4483 static __always_inline struct sk_buff * 4484 sch_handle_egress(struct sk_buff *skb, int *ret, struct net_device *dev) 4485 { 4486 struct bpf_mprog_entry *entry = rcu_dereference_bh(dev->tcx_egress); 4487 enum skb_drop_reason drop_reason = SKB_DROP_REASON_TC_EGRESS; 4488 struct bpf_net_context __bpf_net_ctx, *bpf_net_ctx; 4489 int sch_ret; 4490 4491 if (!entry) 4492 return skb; 4493 4494 bpf_net_ctx = bpf_net_ctx_set(&__bpf_net_ctx); 4495 4496 /* qdisc_skb_cb(skb)->pkt_len & tcx_set_ingress() was 4497 * already set by the caller. 4498 */ 4499 if (static_branch_unlikely(&tcx_needed_key)) { 4500 sch_ret = tcx_run(entry, skb, false); 4501 if (sch_ret != TC_ACT_UNSPEC) 4502 goto egress_verdict; 4503 } 4504 sch_ret = tc_run(tcx_entry(entry), skb, &drop_reason); 4505 egress_verdict: 4506 switch (sch_ret) { 4507 case TC_ACT_REDIRECT: 4508 /* No need to push/pop skb's mac_header here on egress! */ 4509 skb_do_redirect(skb); 4510 *ret = NET_XMIT_SUCCESS; 4511 bpf_net_ctx_clear(bpf_net_ctx); 4512 return NULL; 4513 case TC_ACT_SHOT: 4514 kfree_skb_reason(skb, drop_reason); 4515 *ret = NET_XMIT_DROP; 4516 bpf_net_ctx_clear(bpf_net_ctx); 4517 return NULL; 4518 /* used by tc_run */ 4519 case TC_ACT_STOLEN: 4520 case TC_ACT_QUEUED: 4521 case TC_ACT_TRAP: 4522 consume_skb(skb); 4523 fallthrough; 4524 case TC_ACT_CONSUMED: 4525 *ret = NET_XMIT_SUCCESS; 4526 bpf_net_ctx_clear(bpf_net_ctx); 4527 return NULL; 4528 } 4529 bpf_net_ctx_clear(bpf_net_ctx); 4530 4531 return skb; 4532 } 4533 #else 4534 static __always_inline struct sk_buff * 4535 sch_handle_ingress(struct sk_buff *skb, struct packet_type **pt_prev, int *ret, 4536 struct net_device *orig_dev, bool *another) 4537 { 4538 return skb; 4539 } 4540 4541 static __always_inline struct sk_buff * 4542 sch_handle_egress(struct sk_buff *skb, int *ret, struct net_device *dev) 4543 { 4544 return skb; 4545 } 4546 #endif /* CONFIG_NET_XGRESS */ 4547 4548 #ifdef CONFIG_XPS 4549 static int __get_xps_queue_idx(struct net_device *dev, struct sk_buff *skb, 4550 struct xps_dev_maps *dev_maps, unsigned int tci) 4551 { 4552 int tc = netdev_get_prio_tc_map(dev, skb->priority); 4553 struct xps_map *map; 4554 int queue_index = -1; 4555 4556 if (tc >= dev_maps->num_tc || tci >= dev_maps->nr_ids) 4557 return queue_index; 4558 4559 tci *= dev_maps->num_tc; 4560 tci += tc; 4561 4562 map = rcu_dereference(dev_maps->attr_map[tci]); 4563 if (map) { 4564 if (map->len == 1) 4565 queue_index = map->queues[0]; 4566 else 4567 queue_index = map->queues[reciprocal_scale( 4568 skb_get_hash(skb), map->len)]; 4569 if (unlikely(queue_index >= dev->real_num_tx_queues)) 4570 queue_index = -1; 4571 } 4572 return queue_index; 4573 } 4574 #endif 4575 4576 static int get_xps_queue(struct net_device *dev, struct net_device *sb_dev, 4577 struct sk_buff *skb) 4578 { 4579 #ifdef CONFIG_XPS 4580 struct xps_dev_maps *dev_maps; 4581 struct sock *sk = skb->sk; 4582 int queue_index = -1; 4583 4584 if (!static_key_false(&xps_needed)) 4585 return -1; 4586 4587 rcu_read_lock(); 4588 if (!static_key_false(&xps_rxqs_needed)) 4589 goto get_cpus_map; 4590 4591 dev_maps = rcu_dereference(sb_dev->xps_maps[XPS_RXQS]); 4592 if (dev_maps) { 4593 int tci = sk_rx_queue_get(sk); 4594 4595 if (tci >= 0) 4596 queue_index = __get_xps_queue_idx(dev, skb, dev_maps, 4597 tci); 4598 } 4599 4600 get_cpus_map: 4601 if (queue_index < 0) { 4602 dev_maps = rcu_dereference(sb_dev->xps_maps[XPS_CPUS]); 4603 if (dev_maps) { 4604 unsigned int tci = skb->sender_cpu - 1; 4605 4606 queue_index = __get_xps_queue_idx(dev, skb, dev_maps, 4607 tci); 4608 } 4609 } 4610 rcu_read_unlock(); 4611 4612 return queue_index; 4613 #else 4614 return -1; 4615 #endif 4616 } 4617 4618 u16 dev_pick_tx_zero(struct net_device *dev, struct sk_buff *skb, 4619 struct net_device *sb_dev) 4620 { 4621 return 0; 4622 } 4623 EXPORT_SYMBOL(dev_pick_tx_zero); 4624 4625 u16 netdev_pick_tx(struct net_device *dev, struct sk_buff *skb, 4626 struct net_device *sb_dev) 4627 { 4628 struct sock *sk = skb->sk; 4629 int queue_index = sk_tx_queue_get(sk); 4630 4631 sb_dev = sb_dev ? : dev; 4632 4633 if (queue_index < 0 || skb->ooo_okay || 4634 queue_index >= dev->real_num_tx_queues) { 4635 int new_index = get_xps_queue(dev, sb_dev, skb); 4636 4637 if (new_index < 0) 4638 new_index = skb_tx_hash(dev, sb_dev, skb); 4639 4640 if (queue_index != new_index && sk && 4641 sk_fullsock(sk) && 4642 rcu_access_pointer(sk->sk_dst_cache)) 4643 sk_tx_queue_set(sk, new_index); 4644 4645 queue_index = new_index; 4646 } 4647 4648 return queue_index; 4649 } 4650 EXPORT_SYMBOL(netdev_pick_tx); 4651 4652 struct netdev_queue *netdev_core_pick_tx(struct net_device *dev, 4653 struct sk_buff *skb, 4654 struct net_device *sb_dev) 4655 { 4656 int queue_index = 0; 4657 4658 #ifdef CONFIG_XPS 4659 u32 sender_cpu = skb->sender_cpu - 1; 4660 4661 if (sender_cpu >= (u32)NR_CPUS) 4662 skb->sender_cpu = raw_smp_processor_id() + 1; 4663 #endif 4664 4665 if (dev->real_num_tx_queues != 1) { 4666 const struct net_device_ops *ops = dev->netdev_ops; 4667 4668 if (ops->ndo_select_queue) 4669 queue_index = ops->ndo_select_queue(dev, skb, sb_dev); 4670 else 4671 queue_index = netdev_pick_tx(dev, skb, sb_dev); 4672 4673 queue_index = netdev_cap_txqueue(dev, queue_index); 4674 } 4675 4676 skb_set_queue_mapping(skb, queue_index); 4677 return netdev_get_tx_queue(dev, queue_index); 4678 } 4679 4680 /** 4681 * __dev_queue_xmit() - transmit a buffer 4682 * @skb: buffer to transmit 4683 * @sb_dev: suboordinate device used for L2 forwarding offload 4684 * 4685 * Queue a buffer for transmission to a network device. The caller must 4686 * have set the device and priority and built the buffer before calling 4687 * this function. The function can be called from an interrupt. 4688 * 4689 * When calling this method, interrupts MUST be enabled. This is because 4690 * the BH enable code must have IRQs enabled so that it will not deadlock. 4691 * 4692 * Regardless of the return value, the skb is consumed, so it is currently 4693 * difficult to retry a send to this method. (You can bump the ref count 4694 * before sending to hold a reference for retry if you are careful.) 4695 * 4696 * Return: 4697 * * 0 - buffer successfully transmitted 4698 * * positive qdisc return code - NET_XMIT_DROP etc. 4699 * * negative errno - other errors 4700 */ 4701 int __dev_queue_xmit(struct sk_buff *skb, struct net_device *sb_dev) 4702 { 4703 struct net_device *dev = skb->dev; 4704 struct netdev_queue *txq = NULL; 4705 struct Qdisc *q; 4706 int rc = -ENOMEM; 4707 bool again = false; 4708 4709 skb_reset_mac_header(skb); 4710 skb_assert_len(skb); 4711 4712 if (unlikely(skb_shinfo(skb)->tx_flags & 4713 (SKBTX_SCHED_TSTAMP | SKBTX_BPF))) 4714 __skb_tstamp_tx(skb, NULL, NULL, skb->sk, SCM_TSTAMP_SCHED); 4715 4716 /* Disable soft irqs for various locks below. Also 4717 * stops preemption for RCU. 4718 */ 4719 rcu_read_lock_bh(); 4720 4721 skb_update_prio(skb); 4722 4723 qdisc_pkt_len_init(skb); 4724 tcx_set_ingress(skb, false); 4725 #ifdef CONFIG_NET_EGRESS 4726 if (static_branch_unlikely(&egress_needed_key)) { 4727 if (nf_hook_egress_active()) { 4728 skb = nf_hook_egress(skb, &rc, dev); 4729 if (!skb) 4730 goto out; 4731 } 4732 4733 netdev_xmit_skip_txqueue(false); 4734 4735 nf_skip_egress(skb, true); 4736 skb = sch_handle_egress(skb, &rc, dev); 4737 if (!skb) 4738 goto out; 4739 nf_skip_egress(skb, false); 4740 4741 if (netdev_xmit_txqueue_skipped()) 4742 txq = netdev_tx_queue_mapping(dev, skb); 4743 } 4744 #endif 4745 /* If device/qdisc don't need skb->dst, release it right now while 4746 * its hot in this cpu cache. 4747 */ 4748 if (dev->priv_flags & IFF_XMIT_DST_RELEASE) 4749 skb_dst_drop(skb); 4750 else 4751 skb_dst_force(skb); 4752 4753 if (!txq) 4754 txq = netdev_core_pick_tx(dev, skb, sb_dev); 4755 4756 q = rcu_dereference_bh(txq->qdisc); 4757 4758 trace_net_dev_queue(skb); 4759 if (q->enqueue) { 4760 rc = __dev_xmit_skb(skb, q, dev, txq); 4761 goto out; 4762 } 4763 4764 /* The device has no queue. Common case for software devices: 4765 * loopback, all the sorts of tunnels... 4766 4767 * Really, it is unlikely that netif_tx_lock protection is necessary 4768 * here. (f.e. loopback and IP tunnels are clean ignoring statistics 4769 * counters.) 4770 * However, it is possible, that they rely on protection 4771 * made by us here. 4772 4773 * Check this and shot the lock. It is not prone from deadlocks. 4774 *Either shot noqueue qdisc, it is even simpler 8) 4775 */ 4776 if (dev->flags & IFF_UP) { 4777 int cpu = smp_processor_id(); /* ok because BHs are off */ 4778 4779 if (!netif_tx_owned(txq, cpu)) { 4780 bool is_list = false; 4781 4782 if (dev_xmit_recursion()) 4783 goto recursion_alert; 4784 4785 skb = validate_xmit_skb(skb, dev, &again); 4786 if (!skb) 4787 goto out; 4788 4789 HARD_TX_LOCK(dev, txq, cpu); 4790 4791 if (!netif_xmit_stopped(txq)) { 4792 is_list = !!skb->next; 4793 4794 dev_xmit_recursion_inc(); 4795 skb = dev_hard_start_xmit(skb, dev, txq, &rc); 4796 dev_xmit_recursion_dec(); 4797 4798 /* GSO segments a single SKB into 4799 * a list of frames. TCP expects error 4800 * to mean none of the data was sent. 4801 */ 4802 if (is_list) 4803 rc = NETDEV_TX_OK; 4804 } 4805 HARD_TX_UNLOCK(dev, txq); 4806 if (!skb) /* xmit completed */ 4807 goto out; 4808 4809 net_crit_ratelimited("Virtual device %s asks to queue packet!\n", 4810 dev->name); 4811 /* NETDEV_TX_BUSY or queue was stopped */ 4812 if (!is_list) 4813 rc = -ENETDOWN; 4814 } else { 4815 /* Recursion is detected! It is possible, 4816 * unfortunately 4817 */ 4818 recursion_alert: 4819 net_crit_ratelimited("Dead loop on virtual device %s, fix it urgently!\n", 4820 dev->name); 4821 rc = -ENETDOWN; 4822 } 4823 } 4824 4825 rcu_read_unlock_bh(); 4826 4827 dev_core_stats_tx_dropped_inc(dev); 4828 kfree_skb_list(skb); 4829 return rc; 4830 out: 4831 rcu_read_unlock_bh(); 4832 return rc; 4833 } 4834 EXPORT_SYMBOL(__dev_queue_xmit); 4835 4836 int __dev_direct_xmit(struct sk_buff *skb, u16 queue_id) 4837 { 4838 struct net_device *dev = skb->dev; 4839 struct sk_buff *orig_skb = skb; 4840 struct netdev_queue *txq; 4841 int ret = NETDEV_TX_BUSY; 4842 bool again = false; 4843 4844 if (unlikely(!netif_running(dev) || 4845 !netif_carrier_ok(dev))) 4846 goto drop; 4847 4848 skb = validate_xmit_skb_list(skb, dev, &again); 4849 if (skb != orig_skb) 4850 goto drop; 4851 4852 skb_set_queue_mapping(skb, queue_id); 4853 txq = skb_get_tx_queue(dev, skb); 4854 4855 local_bh_disable(); 4856 4857 dev_xmit_recursion_inc(); 4858 HARD_TX_LOCK(dev, txq, smp_processor_id()); 4859 if (!netif_xmit_frozen_or_drv_stopped(txq)) 4860 ret = netdev_start_xmit(skb, dev, txq, false); 4861 HARD_TX_UNLOCK(dev, txq); 4862 dev_xmit_recursion_dec(); 4863 4864 local_bh_enable(); 4865 return ret; 4866 drop: 4867 dev_core_stats_tx_dropped_inc(dev); 4868 kfree_skb_list(skb); 4869 return NET_XMIT_DROP; 4870 } 4871 EXPORT_SYMBOL(__dev_direct_xmit); 4872 4873 /************************************************************************* 4874 * Receiver routines 4875 *************************************************************************/ 4876 static DEFINE_PER_CPU(struct task_struct *, backlog_napi); 4877 4878 int weight_p __read_mostly = 64; /* old backlog weight */ 4879 int dev_weight_rx_bias __read_mostly = 1; /* bias for backlog weight */ 4880 int dev_weight_tx_bias __read_mostly = 1; /* bias for output_queue quota */ 4881 4882 /* Called with irq disabled */ 4883 static inline void ____napi_schedule(struct softnet_data *sd, 4884 struct napi_struct *napi) 4885 { 4886 struct task_struct *thread; 4887 4888 lockdep_assert_irqs_disabled(); 4889 4890 if (test_bit(NAPI_STATE_THREADED, &napi->state)) { 4891 /* Paired with smp_mb__before_atomic() in 4892 * napi_enable()/netif_set_threaded(). 4893 * Use READ_ONCE() to guarantee a complete 4894 * read on napi->thread. Only call 4895 * wake_up_process() when it's not NULL. 4896 */ 4897 thread = READ_ONCE(napi->thread); 4898 if (thread) { 4899 if (use_backlog_threads() && thread == raw_cpu_read(backlog_napi)) 4900 goto use_local_napi; 4901 4902 set_bit(NAPI_STATE_SCHED_THREADED, &napi->state); 4903 wake_up_process(thread); 4904 return; 4905 } 4906 } 4907 4908 use_local_napi: 4909 DEBUG_NET_WARN_ON_ONCE(!list_empty(&napi->poll_list)); 4910 list_add_tail(&napi->poll_list, &sd->poll_list); 4911 WRITE_ONCE(napi->list_owner, smp_processor_id()); 4912 /* If not called from net_rx_action() 4913 * we have to raise NET_RX_SOFTIRQ. 4914 */ 4915 if (!sd->in_net_rx_action) 4916 raise_softirq_irqoff(NET_RX_SOFTIRQ); 4917 } 4918 4919 #ifdef CONFIG_RPS 4920 4921 struct static_key_false rps_needed __read_mostly; 4922 EXPORT_SYMBOL(rps_needed); 4923 struct static_key_false rfs_needed __read_mostly; 4924 EXPORT_SYMBOL(rfs_needed); 4925 4926 static u32 rfs_slot(u32 hash, const struct rps_dev_flow_table *flow_table) 4927 { 4928 return hash_32(hash, flow_table->log); 4929 } 4930 4931 #ifdef CONFIG_RFS_ACCEL 4932 /** 4933 * rps_flow_is_active - check whether the flow is recently active. 4934 * @rflow: Specific flow to check activity. 4935 * @flow_table: per-queue flowtable that @rflow belongs to. 4936 * @cpu: CPU saved in @rflow. 4937 * 4938 * If the CPU has processed many packets since the flow's last activity 4939 * (beyond 10 times the table size), the flow is considered stale. 4940 * 4941 * Return: true if flow was recently active. 4942 */ 4943 static bool rps_flow_is_active(struct rps_dev_flow *rflow, 4944 struct rps_dev_flow_table *flow_table, 4945 unsigned int cpu) 4946 { 4947 unsigned int flow_last_active; 4948 unsigned int sd_input_head; 4949 4950 if (cpu >= nr_cpu_ids) 4951 return false; 4952 4953 sd_input_head = READ_ONCE(per_cpu(softnet_data, cpu).input_queue_head); 4954 flow_last_active = READ_ONCE(rflow->last_qtail); 4955 4956 return (int)(sd_input_head - flow_last_active) < 4957 (int)(10 << flow_table->log); 4958 } 4959 #endif 4960 4961 static struct rps_dev_flow * 4962 set_rps_cpu(struct net_device *dev, struct sk_buff *skb, 4963 struct rps_dev_flow *rflow, u16 next_cpu, u32 hash) 4964 { 4965 if (next_cpu < nr_cpu_ids) { 4966 u32 head; 4967 #ifdef CONFIG_RFS_ACCEL 4968 struct netdev_rx_queue *rxqueue; 4969 struct rps_dev_flow_table *flow_table; 4970 struct rps_dev_flow *old_rflow; 4971 struct rps_dev_flow *tmp_rflow; 4972 unsigned int tmp_cpu; 4973 u16 rxq_index; 4974 u32 flow_id; 4975 int rc; 4976 4977 /* Should we steer this flow to a different hardware queue? */ 4978 if (!skb_rx_queue_recorded(skb) || !dev->rx_cpu_rmap || 4979 !(dev->features & NETIF_F_NTUPLE)) 4980 goto out; 4981 rxq_index = cpu_rmap_lookup_index(dev->rx_cpu_rmap, next_cpu); 4982 if (rxq_index == skb_get_rx_queue(skb)) 4983 goto out; 4984 4985 rxqueue = dev->_rx + rxq_index; 4986 flow_table = rcu_dereference(rxqueue->rps_flow_table); 4987 if (!flow_table) 4988 goto out; 4989 4990 flow_id = rfs_slot(hash, flow_table); 4991 tmp_rflow = &flow_table->flows[flow_id]; 4992 tmp_cpu = READ_ONCE(tmp_rflow->cpu); 4993 4994 if (READ_ONCE(tmp_rflow->filter) != RPS_NO_FILTER) { 4995 if (rps_flow_is_active(tmp_rflow, flow_table, 4996 tmp_cpu)) { 4997 if (hash != READ_ONCE(tmp_rflow->hash) || 4998 next_cpu == tmp_cpu) 4999 goto out; 5000 } 5001 } 5002 5003 rc = dev->netdev_ops->ndo_rx_flow_steer(dev, skb, 5004 rxq_index, flow_id); 5005 if (rc < 0) 5006 goto out; 5007 5008 old_rflow = rflow; 5009 rflow = tmp_rflow; 5010 WRITE_ONCE(rflow->filter, rc); 5011 WRITE_ONCE(rflow->hash, hash); 5012 5013 if (old_rflow->filter == rc) 5014 WRITE_ONCE(old_rflow->filter, RPS_NO_FILTER); 5015 out: 5016 #endif 5017 head = READ_ONCE(per_cpu(softnet_data, next_cpu).input_queue_head); 5018 rps_input_queue_tail_save(&rflow->last_qtail, head); 5019 } 5020 5021 WRITE_ONCE(rflow->cpu, next_cpu); 5022 return rflow; 5023 } 5024 5025 /* 5026 * get_rps_cpu is called from netif_receive_skb and returns the target 5027 * CPU from the RPS map of the receiving queue for a given skb. 5028 * rcu_read_lock must be held on entry. 5029 */ 5030 static int get_rps_cpu(struct net_device *dev, struct sk_buff *skb, 5031 struct rps_dev_flow **rflowp) 5032 { 5033 const struct rps_sock_flow_table *sock_flow_table; 5034 struct netdev_rx_queue *rxqueue = dev->_rx; 5035 struct rps_dev_flow_table *flow_table; 5036 struct rps_map *map; 5037 int cpu = -1; 5038 u32 tcpu; 5039 u32 hash; 5040 5041 if (skb_rx_queue_recorded(skb)) { 5042 u16 index = skb_get_rx_queue(skb); 5043 5044 if (unlikely(index >= dev->real_num_rx_queues)) { 5045 WARN_ONCE(dev->real_num_rx_queues > 1, 5046 "%s received packet on queue %u, but number " 5047 "of RX queues is %u\n", 5048 dev->name, index, dev->real_num_rx_queues); 5049 goto done; 5050 } 5051 rxqueue += index; 5052 } 5053 5054 /* Avoid computing hash if RFS/RPS is not active for this rxqueue */ 5055 5056 flow_table = rcu_dereference(rxqueue->rps_flow_table); 5057 map = rcu_dereference(rxqueue->rps_map); 5058 if (!flow_table && !map) 5059 goto done; 5060 5061 skb_reset_network_header(skb); 5062 hash = skb_get_hash(skb); 5063 if (!hash) 5064 goto done; 5065 5066 sock_flow_table = rcu_dereference(net_hotdata.rps_sock_flow_table); 5067 if (flow_table && sock_flow_table) { 5068 struct rps_dev_flow *rflow; 5069 u32 next_cpu; 5070 u32 ident; 5071 5072 /* First check into global flow table if there is a match. 5073 * This READ_ONCE() pairs with WRITE_ONCE() from rps_record_sock_flow(). 5074 */ 5075 ident = READ_ONCE(sock_flow_table->ents[hash & sock_flow_table->mask]); 5076 if ((ident ^ hash) & ~net_hotdata.rps_cpu_mask) 5077 goto try_rps; 5078 5079 next_cpu = ident & net_hotdata.rps_cpu_mask; 5080 5081 /* OK, now we know there is a match, 5082 * we can look at the local (per receive queue) flow table 5083 */ 5084 rflow = &flow_table->flows[rfs_slot(hash, flow_table)]; 5085 tcpu = rflow->cpu; 5086 5087 /* 5088 * If the desired CPU (where last recvmsg was done) is 5089 * different from current CPU (one in the rx-queue flow 5090 * table entry), switch if one of the following holds: 5091 * - Current CPU is unset (>= nr_cpu_ids). 5092 * - Current CPU is offline. 5093 * - The current CPU's queue tail has advanced beyond the 5094 * last packet that was enqueued using this table entry. 5095 * This guarantees that all previous packets for the flow 5096 * have been dequeued, thus preserving in order delivery. 5097 */ 5098 if (unlikely(tcpu != next_cpu) && 5099 (tcpu >= nr_cpu_ids || !cpu_online(tcpu) || 5100 ((int)(READ_ONCE(per_cpu(softnet_data, tcpu).input_queue_head) - 5101 rflow->last_qtail)) >= 0)) { 5102 tcpu = next_cpu; 5103 rflow = set_rps_cpu(dev, skb, rflow, next_cpu, hash); 5104 } 5105 5106 if (tcpu < nr_cpu_ids && cpu_online(tcpu)) { 5107 *rflowp = rflow; 5108 cpu = tcpu; 5109 goto done; 5110 } 5111 } 5112 5113 try_rps: 5114 5115 if (map) { 5116 tcpu = map->cpus[reciprocal_scale(hash, map->len)]; 5117 if (cpu_online(tcpu)) { 5118 cpu = tcpu; 5119 goto done; 5120 } 5121 } 5122 5123 done: 5124 return cpu; 5125 } 5126 5127 #ifdef CONFIG_RFS_ACCEL 5128 5129 /** 5130 * rps_may_expire_flow - check whether an RFS hardware filter may be removed 5131 * @dev: Device on which the filter was set 5132 * @rxq_index: RX queue index 5133 * @flow_id: Flow ID passed to ndo_rx_flow_steer() 5134 * @filter_id: Filter ID returned by ndo_rx_flow_steer() 5135 * 5136 * Drivers that implement ndo_rx_flow_steer() should periodically call 5137 * this function for each installed filter and remove the filters for 5138 * which it returns %true. 5139 */ 5140 bool rps_may_expire_flow(struct net_device *dev, u16 rxq_index, 5141 u32 flow_id, u16 filter_id) 5142 { 5143 struct netdev_rx_queue *rxqueue = dev->_rx + rxq_index; 5144 struct rps_dev_flow_table *flow_table; 5145 struct rps_dev_flow *rflow; 5146 bool expire = true; 5147 5148 rcu_read_lock(); 5149 flow_table = rcu_dereference(rxqueue->rps_flow_table); 5150 if (flow_table && flow_id < (1UL << flow_table->log)) { 5151 unsigned int cpu; 5152 5153 rflow = &flow_table->flows[flow_id]; 5154 cpu = READ_ONCE(rflow->cpu); 5155 if (READ_ONCE(rflow->filter) == filter_id && 5156 rps_flow_is_active(rflow, flow_table, cpu)) 5157 expire = false; 5158 } 5159 rcu_read_unlock(); 5160 return expire; 5161 } 5162 EXPORT_SYMBOL(rps_may_expire_flow); 5163 5164 #endif /* CONFIG_RFS_ACCEL */ 5165 5166 /* Called from hardirq (IPI) context */ 5167 static void rps_trigger_softirq(void *data) 5168 { 5169 struct softnet_data *sd = data; 5170 5171 ____napi_schedule(sd, &sd->backlog); 5172 /* Pairs with READ_ONCE() in softnet_seq_show() */ 5173 WRITE_ONCE(sd->received_rps, sd->received_rps + 1); 5174 } 5175 5176 #endif /* CONFIG_RPS */ 5177 5178 /* Called from hardirq (IPI) context */ 5179 static void trigger_rx_softirq(void *data) 5180 { 5181 struct softnet_data *sd = data; 5182 5183 __raise_softirq_irqoff(NET_RX_SOFTIRQ); 5184 smp_store_release(&sd->defer_ipi_scheduled, 0); 5185 } 5186 5187 /* 5188 * After we queued a packet into sd->input_pkt_queue, 5189 * we need to make sure this queue is serviced soon. 5190 * 5191 * - If this is another cpu queue, link it to our rps_ipi_list, 5192 * and make sure we will process rps_ipi_list from net_rx_action(). 5193 * 5194 * - If this is our own queue, NAPI schedule our backlog. 5195 * Note that this also raises NET_RX_SOFTIRQ. 5196 */ 5197 static void napi_schedule_rps(struct softnet_data *sd) 5198 { 5199 struct softnet_data *mysd = this_cpu_ptr(&softnet_data); 5200 5201 #ifdef CONFIG_RPS 5202 if (sd != mysd) { 5203 if (use_backlog_threads()) { 5204 __napi_schedule_irqoff(&sd->backlog); 5205 return; 5206 } 5207 5208 sd->rps_ipi_next = mysd->rps_ipi_list; 5209 mysd->rps_ipi_list = sd; 5210 5211 /* If not called from net_rx_action() or napi_threaded_poll() 5212 * we have to raise NET_RX_SOFTIRQ. 5213 */ 5214 if (!mysd->in_net_rx_action && !mysd->in_napi_threaded_poll) 5215 __raise_softirq_irqoff(NET_RX_SOFTIRQ); 5216 return; 5217 } 5218 #endif /* CONFIG_RPS */ 5219 __napi_schedule_irqoff(&mysd->backlog); 5220 } 5221 5222 void kick_defer_list_purge(unsigned int cpu) 5223 { 5224 struct softnet_data *sd = &per_cpu(softnet_data, cpu); 5225 unsigned long flags; 5226 5227 if (use_backlog_threads()) { 5228 backlog_lock_irq_save(sd, &flags); 5229 5230 if (!__test_and_set_bit(NAPI_STATE_SCHED, &sd->backlog.state)) 5231 __napi_schedule_irqoff(&sd->backlog); 5232 5233 backlog_unlock_irq_restore(sd, &flags); 5234 5235 } else if (!cmpxchg(&sd->defer_ipi_scheduled, 0, 1)) { 5236 smp_call_function_single_async(cpu, &sd->defer_csd); 5237 } 5238 } 5239 5240 #ifdef CONFIG_NET_FLOW_LIMIT 5241 int netdev_flow_limit_table_len __read_mostly = (1 << 12); 5242 #endif 5243 5244 static bool skb_flow_limit(struct sk_buff *skb, unsigned int qlen) 5245 { 5246 #ifdef CONFIG_NET_FLOW_LIMIT 5247 struct sd_flow_limit *fl; 5248 struct softnet_data *sd; 5249 unsigned int old_flow, new_flow; 5250 5251 if (qlen < (READ_ONCE(net_hotdata.max_backlog) >> 1)) 5252 return false; 5253 5254 sd = this_cpu_ptr(&softnet_data); 5255 5256 rcu_read_lock(); 5257 fl = rcu_dereference(sd->flow_limit); 5258 if (fl) { 5259 new_flow = hash_32(skb_get_hash(skb), fl->log_buckets); 5260 old_flow = fl->history[fl->history_head]; 5261 fl->history[fl->history_head] = new_flow; 5262 5263 fl->history_head++; 5264 fl->history_head &= FLOW_LIMIT_HISTORY - 1; 5265 5266 if (likely(fl->buckets[old_flow])) 5267 fl->buckets[old_flow]--; 5268 5269 if (++fl->buckets[new_flow] > (FLOW_LIMIT_HISTORY >> 1)) { 5270 /* Pairs with READ_ONCE() in softnet_seq_show() */ 5271 WRITE_ONCE(fl->count, fl->count + 1); 5272 rcu_read_unlock(); 5273 return true; 5274 } 5275 } 5276 rcu_read_unlock(); 5277 #endif 5278 return false; 5279 } 5280 5281 /* 5282 * enqueue_to_backlog is called to queue an skb to a per CPU backlog 5283 * queue (may be a remote CPU queue). 5284 */ 5285 static int enqueue_to_backlog(struct sk_buff *skb, int cpu, 5286 unsigned int *qtail) 5287 { 5288 enum skb_drop_reason reason; 5289 struct softnet_data *sd; 5290 unsigned long flags; 5291 unsigned int qlen; 5292 int max_backlog; 5293 u32 tail; 5294 5295 reason = SKB_DROP_REASON_DEV_READY; 5296 if (!netif_running(skb->dev)) 5297 goto bad_dev; 5298 5299 reason = SKB_DROP_REASON_CPU_BACKLOG; 5300 sd = &per_cpu(softnet_data, cpu); 5301 5302 qlen = skb_queue_len_lockless(&sd->input_pkt_queue); 5303 max_backlog = READ_ONCE(net_hotdata.max_backlog); 5304 if (unlikely(qlen > max_backlog)) 5305 goto cpu_backlog_drop; 5306 backlog_lock_irq_save(sd, &flags); 5307 qlen = skb_queue_len(&sd->input_pkt_queue); 5308 if (qlen <= max_backlog && !skb_flow_limit(skb, qlen)) { 5309 if (!qlen) { 5310 /* Schedule NAPI for backlog device. We can use 5311 * non atomic operation as we own the queue lock. 5312 */ 5313 if (!__test_and_set_bit(NAPI_STATE_SCHED, 5314 &sd->backlog.state)) 5315 napi_schedule_rps(sd); 5316 } 5317 __skb_queue_tail(&sd->input_pkt_queue, skb); 5318 tail = rps_input_queue_tail_incr(sd); 5319 backlog_unlock_irq_restore(sd, &flags); 5320 5321 /* save the tail outside of the critical section */ 5322 rps_input_queue_tail_save(qtail, tail); 5323 return NET_RX_SUCCESS; 5324 } 5325 5326 backlog_unlock_irq_restore(sd, &flags); 5327 5328 cpu_backlog_drop: 5329 numa_drop_add(&sd->drop_counters, 1); 5330 bad_dev: 5331 dev_core_stats_rx_dropped_inc(skb->dev); 5332 kfree_skb_reason(skb, reason); 5333 return NET_RX_DROP; 5334 } 5335 5336 static struct netdev_rx_queue *netif_get_rxqueue(struct sk_buff *skb) 5337 { 5338 struct net_device *dev = skb->dev; 5339 struct netdev_rx_queue *rxqueue; 5340 5341 rxqueue = dev->_rx; 5342 5343 if (skb_rx_queue_recorded(skb)) { 5344 u16 index = skb_get_rx_queue(skb); 5345 5346 if (unlikely(index >= dev->real_num_rx_queues)) { 5347 WARN_ONCE(dev->real_num_rx_queues > 1, 5348 "%s received packet on queue %u, but number " 5349 "of RX queues is %u\n", 5350 dev->name, index, dev->real_num_rx_queues); 5351 5352 return rxqueue; /* Return first rxqueue */ 5353 } 5354 rxqueue += index; 5355 } 5356 return rxqueue; 5357 } 5358 5359 u32 bpf_prog_run_generic_xdp(struct sk_buff *skb, struct xdp_buff *xdp, 5360 const struct bpf_prog *xdp_prog) 5361 { 5362 void *orig_data, *orig_data_end, *hard_start; 5363 struct netdev_rx_queue *rxqueue; 5364 bool orig_bcast, orig_host; 5365 u32 mac_len, frame_sz; 5366 __be16 orig_eth_type; 5367 struct ethhdr *eth; 5368 u32 metalen, act; 5369 int off; 5370 5371 /* The XDP program wants to see the packet starting at the MAC 5372 * header. 5373 */ 5374 mac_len = skb->data - skb_mac_header(skb); 5375 hard_start = skb->data - skb_headroom(skb); 5376 5377 /* SKB "head" area always have tailroom for skb_shared_info */ 5378 frame_sz = (void *)skb_end_pointer(skb) - hard_start; 5379 frame_sz += SKB_DATA_ALIGN(sizeof(struct skb_shared_info)); 5380 5381 rxqueue = netif_get_rxqueue(skb); 5382 xdp_init_buff(xdp, frame_sz, &rxqueue->xdp_rxq); 5383 xdp_prepare_buff(xdp, hard_start, skb_headroom(skb) - mac_len, 5384 skb_headlen(skb) + mac_len, true); 5385 if (skb_is_nonlinear(skb)) { 5386 skb_shinfo(skb)->xdp_frags_size = skb->data_len; 5387 xdp_buff_set_frags_flag(xdp); 5388 } else { 5389 xdp_buff_clear_frags_flag(xdp); 5390 } 5391 5392 orig_data_end = xdp->data_end; 5393 orig_data = xdp->data; 5394 eth = (struct ethhdr *)xdp->data; 5395 orig_host = ether_addr_equal_64bits(eth->h_dest, skb->dev->dev_addr); 5396 orig_bcast = is_multicast_ether_addr_64bits(eth->h_dest); 5397 orig_eth_type = eth->h_proto; 5398 5399 act = bpf_prog_run_xdp(xdp_prog, xdp); 5400 5401 /* check if bpf_xdp_adjust_head was used */ 5402 off = xdp->data - orig_data; 5403 if (off) { 5404 if (off > 0) 5405 __skb_pull(skb, off); 5406 else if (off < 0) 5407 __skb_push(skb, -off); 5408 5409 skb->mac_header += off; 5410 skb_reset_network_header(skb); 5411 } 5412 5413 /* check if bpf_xdp_adjust_tail was used */ 5414 off = xdp->data_end - orig_data_end; 5415 if (off != 0) { 5416 skb_set_tail_pointer(skb, xdp->data_end - xdp->data); 5417 skb->len += off; /* positive on grow, negative on shrink */ 5418 } 5419 5420 /* XDP frag metadata (e.g. nr_frags) are updated in eBPF helpers 5421 * (e.g. bpf_xdp_adjust_tail), we need to update data_len here. 5422 */ 5423 if (xdp_buff_has_frags(xdp)) 5424 skb->data_len = skb_shinfo(skb)->xdp_frags_size; 5425 else 5426 skb->data_len = 0; 5427 5428 /* check if XDP changed eth hdr such SKB needs update */ 5429 eth = (struct ethhdr *)xdp->data; 5430 if ((orig_eth_type != eth->h_proto) || 5431 (orig_host != ether_addr_equal_64bits(eth->h_dest, 5432 skb->dev->dev_addr)) || 5433 (orig_bcast != is_multicast_ether_addr_64bits(eth->h_dest))) { 5434 __skb_push(skb, ETH_HLEN); 5435 skb->pkt_type = PACKET_HOST; 5436 skb->protocol = eth_type_trans(skb, skb->dev); 5437 } 5438 5439 /* Redirect/Tx gives L2 packet, code that will reuse skb must __skb_pull 5440 * before calling us again on redirect path. We do not call do_redirect 5441 * as we leave that up to the caller. 5442 * 5443 * Caller is responsible for managing lifetime of skb (i.e. calling 5444 * kfree_skb in response to actions it cannot handle/XDP_DROP). 5445 */ 5446 switch (act) { 5447 case XDP_REDIRECT: 5448 case XDP_TX: 5449 __skb_push(skb, mac_len); 5450 break; 5451 case XDP_PASS: 5452 metalen = xdp->data - xdp->data_meta; 5453 if (metalen) 5454 skb_metadata_set(skb, metalen); 5455 break; 5456 } 5457 5458 return act; 5459 } 5460 5461 static int 5462 netif_skb_check_for_xdp(struct sk_buff **pskb, const struct bpf_prog *prog) 5463 { 5464 struct sk_buff *skb = *pskb; 5465 int err, hroom, troom; 5466 5467 local_lock_nested_bh(&system_page_pool.bh_lock); 5468 err = skb_cow_data_for_xdp(this_cpu_read(system_page_pool.pool), pskb, prog); 5469 local_unlock_nested_bh(&system_page_pool.bh_lock); 5470 if (!err) 5471 return 0; 5472 5473 /* In case we have to go down the path and also linearize, 5474 * then lets do the pskb_expand_head() work just once here. 5475 */ 5476 hroom = XDP_PACKET_HEADROOM - skb_headroom(skb); 5477 troom = skb->tail + skb->data_len - skb->end; 5478 err = pskb_expand_head(skb, 5479 hroom > 0 ? ALIGN(hroom, NET_SKB_PAD) : 0, 5480 troom > 0 ? troom + 128 : 0, GFP_ATOMIC); 5481 if (err) 5482 return err; 5483 5484 return skb_linearize(skb); 5485 } 5486 5487 static u32 netif_receive_generic_xdp(struct sk_buff **pskb, 5488 struct xdp_buff *xdp, 5489 const struct bpf_prog *xdp_prog) 5490 { 5491 struct sk_buff *skb = *pskb; 5492 u32 mac_len, act = XDP_DROP; 5493 5494 /* Reinjected packets coming from act_mirred or similar should 5495 * not get XDP generic processing. 5496 */ 5497 if (skb_is_redirected(skb)) 5498 return XDP_PASS; 5499 5500 /* XDP packets must have sufficient headroom of XDP_PACKET_HEADROOM 5501 * bytes. This is the guarantee that also native XDP provides, 5502 * thus we need to do it here as well. 5503 */ 5504 mac_len = skb->data - skb_mac_header(skb); 5505 __skb_push(skb, mac_len); 5506 5507 if (skb_cloned(skb) || skb_is_nonlinear(skb) || 5508 skb_headroom(skb) < XDP_PACKET_HEADROOM) { 5509 if (netif_skb_check_for_xdp(pskb, xdp_prog)) 5510 goto do_drop; 5511 } 5512 5513 __skb_pull(*pskb, mac_len); 5514 5515 act = bpf_prog_run_generic_xdp(*pskb, xdp, xdp_prog); 5516 switch (act) { 5517 case XDP_REDIRECT: 5518 case XDP_TX: 5519 case XDP_PASS: 5520 break; 5521 default: 5522 bpf_warn_invalid_xdp_action((*pskb)->dev, xdp_prog, act); 5523 fallthrough; 5524 case XDP_ABORTED: 5525 trace_xdp_exception((*pskb)->dev, xdp_prog, act); 5526 fallthrough; 5527 case XDP_DROP: 5528 do_drop: 5529 kfree_skb(*pskb); 5530 break; 5531 } 5532 5533 return act; 5534 } 5535 5536 /* When doing generic XDP we have to bypass the qdisc layer and the 5537 * network taps in order to match in-driver-XDP behavior. This also means 5538 * that XDP packets are able to starve other packets going through a qdisc, 5539 * and DDOS attacks will be more effective. In-driver-XDP use dedicated TX 5540 * queues, so they do not have this starvation issue. 5541 */ 5542 void generic_xdp_tx(struct sk_buff *skb, const struct bpf_prog *xdp_prog) 5543 { 5544 struct net_device *dev = skb->dev; 5545 struct netdev_queue *txq; 5546 bool free_skb = true; 5547 int cpu, rc; 5548 5549 txq = netdev_core_pick_tx(dev, skb, NULL); 5550 cpu = smp_processor_id(); 5551 HARD_TX_LOCK(dev, txq, cpu); 5552 if (!netif_xmit_frozen_or_drv_stopped(txq)) { 5553 rc = netdev_start_xmit(skb, dev, txq, 0); 5554 if (dev_xmit_complete(rc)) 5555 free_skb = false; 5556 } 5557 HARD_TX_UNLOCK(dev, txq); 5558 if (free_skb) { 5559 trace_xdp_exception(dev, xdp_prog, XDP_TX); 5560 dev_core_stats_tx_dropped_inc(dev); 5561 kfree_skb(skb); 5562 } 5563 } 5564 5565 static DEFINE_STATIC_KEY_FALSE(generic_xdp_needed_key); 5566 5567 int do_xdp_generic(const struct bpf_prog *xdp_prog, struct sk_buff **pskb) 5568 { 5569 struct bpf_net_context __bpf_net_ctx, *bpf_net_ctx; 5570 5571 if (xdp_prog) { 5572 struct xdp_buff xdp; 5573 u32 act; 5574 int err; 5575 5576 bpf_net_ctx = bpf_net_ctx_set(&__bpf_net_ctx); 5577 act = netif_receive_generic_xdp(pskb, &xdp, xdp_prog); 5578 if (act != XDP_PASS) { 5579 switch (act) { 5580 case XDP_REDIRECT: 5581 err = xdp_do_generic_redirect((*pskb)->dev, *pskb, 5582 &xdp, xdp_prog); 5583 if (err) 5584 goto out_redir; 5585 break; 5586 case XDP_TX: 5587 generic_xdp_tx(*pskb, xdp_prog); 5588 break; 5589 } 5590 bpf_net_ctx_clear(bpf_net_ctx); 5591 return XDP_DROP; 5592 } 5593 bpf_net_ctx_clear(bpf_net_ctx); 5594 } 5595 return XDP_PASS; 5596 out_redir: 5597 bpf_net_ctx_clear(bpf_net_ctx); 5598 kfree_skb_reason(*pskb, SKB_DROP_REASON_XDP); 5599 return XDP_DROP; 5600 } 5601 EXPORT_SYMBOL_GPL(do_xdp_generic); 5602 5603 static int netif_rx_internal(struct sk_buff *skb) 5604 { 5605 int ret; 5606 5607 net_timestamp_check(READ_ONCE(net_hotdata.tstamp_prequeue), skb); 5608 5609 trace_netif_rx(skb); 5610 5611 #ifdef CONFIG_RPS 5612 if (static_branch_unlikely(&rps_needed)) { 5613 struct rps_dev_flow voidflow, *rflow = &voidflow; 5614 int cpu; 5615 5616 rcu_read_lock(); 5617 5618 cpu = get_rps_cpu(skb->dev, skb, &rflow); 5619 if (cpu < 0) 5620 cpu = smp_processor_id(); 5621 5622 ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail); 5623 5624 rcu_read_unlock(); 5625 } else 5626 #endif 5627 { 5628 unsigned int qtail; 5629 5630 ret = enqueue_to_backlog(skb, smp_processor_id(), &qtail); 5631 } 5632 return ret; 5633 } 5634 5635 /** 5636 * __netif_rx - Slightly optimized version of netif_rx 5637 * @skb: buffer to post 5638 * 5639 * This behaves as netif_rx except that it does not disable bottom halves. 5640 * As a result this function may only be invoked from the interrupt context 5641 * (either hard or soft interrupt). 5642 */ 5643 int __netif_rx(struct sk_buff *skb) 5644 { 5645 int ret; 5646 5647 lockdep_assert_once(hardirq_count() | softirq_count()); 5648 5649 trace_netif_rx_entry(skb); 5650 ret = netif_rx_internal(skb); 5651 trace_netif_rx_exit(ret); 5652 return ret; 5653 } 5654 EXPORT_SYMBOL(__netif_rx); 5655 5656 /** 5657 * netif_rx - post buffer to the network code 5658 * @skb: buffer to post 5659 * 5660 * This function receives a packet from a device driver and queues it for 5661 * the upper (protocol) levels to process via the backlog NAPI device. It 5662 * always succeeds. The buffer may be dropped during processing for 5663 * congestion control or by the protocol layers. 5664 * The network buffer is passed via the backlog NAPI device. Modern NIC 5665 * driver should use NAPI and GRO. 5666 * This function can used from interrupt and from process context. The 5667 * caller from process context must not disable interrupts before invoking 5668 * this function. 5669 * 5670 * return values: 5671 * NET_RX_SUCCESS (no congestion) 5672 * NET_RX_DROP (packet was dropped) 5673 * 5674 */ 5675 int netif_rx(struct sk_buff *skb) 5676 { 5677 bool need_bh_off = !(hardirq_count() | softirq_count()); 5678 int ret; 5679 5680 if (need_bh_off) 5681 local_bh_disable(); 5682 trace_netif_rx_entry(skb); 5683 ret = netif_rx_internal(skb); 5684 trace_netif_rx_exit(ret); 5685 if (need_bh_off) 5686 local_bh_enable(); 5687 return ret; 5688 } 5689 EXPORT_SYMBOL(netif_rx); 5690 5691 static __latent_entropy void net_tx_action(void) 5692 { 5693 struct softnet_data *sd = this_cpu_ptr(&softnet_data); 5694 5695 if (sd->completion_queue) { 5696 struct sk_buff *clist; 5697 5698 local_irq_disable(); 5699 clist = sd->completion_queue; 5700 sd->completion_queue = NULL; 5701 local_irq_enable(); 5702 5703 while (clist) { 5704 struct sk_buff *skb = clist; 5705 5706 clist = clist->next; 5707 5708 WARN_ON(refcount_read(&skb->users)); 5709 if (likely(get_kfree_skb_cb(skb)->reason == SKB_CONSUMED)) 5710 trace_consume_skb(skb, net_tx_action); 5711 else 5712 trace_kfree_skb(skb, net_tx_action, 5713 get_kfree_skb_cb(skb)->reason, NULL); 5714 5715 if (skb->fclone != SKB_FCLONE_UNAVAILABLE) 5716 __kfree_skb(skb); 5717 else 5718 __napi_kfree_skb(skb, 5719 get_kfree_skb_cb(skb)->reason); 5720 } 5721 } 5722 5723 if (sd->output_queue) { 5724 struct Qdisc *head; 5725 5726 local_irq_disable(); 5727 head = sd->output_queue; 5728 sd->output_queue = NULL; 5729 sd->output_queue_tailp = &sd->output_queue; 5730 local_irq_enable(); 5731 5732 rcu_read_lock(); 5733 5734 while (head) { 5735 struct Qdisc *q = head; 5736 spinlock_t *root_lock = NULL; 5737 5738 head = head->next_sched; 5739 5740 /* We need to make sure head->next_sched is read 5741 * before clearing __QDISC_STATE_SCHED 5742 */ 5743 smp_mb__before_atomic(); 5744 5745 if (!(q->flags & TCQ_F_NOLOCK)) { 5746 root_lock = qdisc_lock(q); 5747 spin_lock(root_lock); 5748 } else if (unlikely(test_bit(__QDISC_STATE_DEACTIVATED, 5749 &q->state))) { 5750 /* There is a synchronize_net() between 5751 * STATE_DEACTIVATED flag being set and 5752 * qdisc_reset()/some_qdisc_is_busy() in 5753 * dev_deactivate(), so we can safely bail out 5754 * early here to avoid data race between 5755 * qdisc_deactivate() and some_qdisc_is_busy() 5756 * for lockless qdisc. 5757 */ 5758 clear_bit(__QDISC_STATE_SCHED, &q->state); 5759 continue; 5760 } 5761 5762 clear_bit(__QDISC_STATE_SCHED, &q->state); 5763 qdisc_run(q); 5764 if (root_lock) 5765 spin_unlock(root_lock); 5766 } 5767 5768 rcu_read_unlock(); 5769 } 5770 5771 xfrm_dev_backlog(sd); 5772 } 5773 5774 #if IS_ENABLED(CONFIG_BRIDGE) && IS_ENABLED(CONFIG_ATM_LANE) 5775 /* This hook is defined here for ATM LANE */ 5776 int (*br_fdb_test_addr_hook)(struct net_device *dev, 5777 unsigned char *addr) __read_mostly; 5778 EXPORT_SYMBOL_GPL(br_fdb_test_addr_hook); 5779 #endif 5780 5781 /** 5782 * netdev_is_rx_handler_busy - check if receive handler is registered 5783 * @dev: device to check 5784 * 5785 * Check if a receive handler is already registered for a given device. 5786 * Return true if there one. 5787 * 5788 * The caller must hold the rtnl_mutex. 5789 */ 5790 bool netdev_is_rx_handler_busy(struct net_device *dev) 5791 { 5792 ASSERT_RTNL(); 5793 return dev && rtnl_dereference(dev->rx_handler); 5794 } 5795 EXPORT_SYMBOL_GPL(netdev_is_rx_handler_busy); 5796 5797 /** 5798 * netdev_rx_handler_register - register receive handler 5799 * @dev: device to register a handler for 5800 * @rx_handler: receive handler to register 5801 * @rx_handler_data: data pointer that is used by rx handler 5802 * 5803 * Register a receive handler for a device. This handler will then be 5804 * called from __netif_receive_skb. A negative errno code is returned 5805 * on a failure. 5806 * 5807 * The caller must hold the rtnl_mutex. 5808 * 5809 * For a general description of rx_handler, see enum rx_handler_result. 5810 */ 5811 int netdev_rx_handler_register(struct net_device *dev, 5812 rx_handler_func_t *rx_handler, 5813 void *rx_handler_data) 5814 { 5815 if (netdev_is_rx_handler_busy(dev)) 5816 return -EBUSY; 5817 5818 if (dev->priv_flags & IFF_NO_RX_HANDLER) 5819 return -EINVAL; 5820 5821 /* Note: rx_handler_data must be set before rx_handler */ 5822 rcu_assign_pointer(dev->rx_handler_data, rx_handler_data); 5823 rcu_assign_pointer(dev->rx_handler, rx_handler); 5824 5825 return 0; 5826 } 5827 EXPORT_SYMBOL_GPL(netdev_rx_handler_register); 5828 5829 /** 5830 * netdev_rx_handler_unregister - unregister receive handler 5831 * @dev: device to unregister a handler from 5832 * 5833 * Unregister a receive handler from a device. 5834 * 5835 * The caller must hold the rtnl_mutex. 5836 */ 5837 void netdev_rx_handler_unregister(struct net_device *dev) 5838 { 5839 5840 ASSERT_RTNL(); 5841 RCU_INIT_POINTER(dev->rx_handler, NULL); 5842 /* a reader seeing a non NULL rx_handler in a rcu_read_lock() 5843 * section has a guarantee to see a non NULL rx_handler_data 5844 * as well. 5845 */ 5846 synchronize_net(); 5847 RCU_INIT_POINTER(dev->rx_handler_data, NULL); 5848 } 5849 EXPORT_SYMBOL_GPL(netdev_rx_handler_unregister); 5850 5851 /* 5852 * Limit the use of PFMEMALLOC reserves to those protocols that implement 5853 * the special handling of PFMEMALLOC skbs. 5854 */ 5855 static bool skb_pfmemalloc_protocol(struct sk_buff *skb) 5856 { 5857 switch (skb->protocol) { 5858 case htons(ETH_P_ARP): 5859 case htons(ETH_P_IP): 5860 case htons(ETH_P_IPV6): 5861 case htons(ETH_P_8021Q): 5862 case htons(ETH_P_8021AD): 5863 return true; 5864 default: 5865 return false; 5866 } 5867 } 5868 5869 static inline int nf_ingress(struct sk_buff *skb, struct packet_type **pt_prev, 5870 int *ret, struct net_device *orig_dev) 5871 { 5872 if (nf_hook_ingress_active(skb)) { 5873 int ingress_retval; 5874 5875 if (*pt_prev) { 5876 *ret = deliver_skb(skb, *pt_prev, orig_dev); 5877 *pt_prev = NULL; 5878 } 5879 5880 rcu_read_lock(); 5881 ingress_retval = nf_hook_ingress(skb); 5882 rcu_read_unlock(); 5883 return ingress_retval; 5884 } 5885 return 0; 5886 } 5887 5888 static int __netif_receive_skb_core(struct sk_buff **pskb, bool pfmemalloc, 5889 struct packet_type **ppt_prev) 5890 { 5891 enum skb_drop_reason drop_reason = SKB_DROP_REASON_UNHANDLED_PROTO; 5892 struct packet_type *ptype, *pt_prev; 5893 rx_handler_func_t *rx_handler; 5894 struct sk_buff *skb = *pskb; 5895 struct net_device *orig_dev; 5896 bool deliver_exact = false; 5897 int ret = NET_RX_DROP; 5898 __be16 type; 5899 5900 net_timestamp_check(!READ_ONCE(net_hotdata.tstamp_prequeue), skb); 5901 5902 trace_netif_receive_skb(skb); 5903 5904 orig_dev = skb->dev; 5905 5906 skb_reset_network_header(skb); 5907 #if !defined(CONFIG_DEBUG_NET) 5908 /* We plan to no longer reset the transport header here. 5909 * Give some time to fuzzers and dev build to catch bugs 5910 * in network stacks. 5911 */ 5912 if (!skb_transport_header_was_set(skb)) 5913 skb_reset_transport_header(skb); 5914 #endif 5915 skb_reset_mac_len(skb); 5916 5917 pt_prev = NULL; 5918 5919 another_round: 5920 skb->skb_iif = skb->dev->ifindex; 5921 5922 __this_cpu_inc(softnet_data.processed); 5923 5924 if (static_branch_unlikely(&generic_xdp_needed_key)) { 5925 int ret2; 5926 5927 migrate_disable(); 5928 ret2 = do_xdp_generic(rcu_dereference(skb->dev->xdp_prog), 5929 &skb); 5930 migrate_enable(); 5931 5932 if (ret2 != XDP_PASS) { 5933 ret = NET_RX_DROP; 5934 goto out; 5935 } 5936 } 5937 5938 if (eth_type_vlan(skb->protocol)) { 5939 skb = skb_vlan_untag(skb); 5940 if (unlikely(!skb)) 5941 goto out; 5942 } 5943 5944 if (skb_skip_tc_classify(skb)) 5945 goto skip_classify; 5946 5947 if (pfmemalloc) 5948 goto skip_taps; 5949 5950 list_for_each_entry_rcu(ptype, &dev_net_rcu(skb->dev)->ptype_all, 5951 list) { 5952 if (pt_prev) 5953 ret = deliver_skb(skb, pt_prev, orig_dev); 5954 pt_prev = ptype; 5955 } 5956 5957 list_for_each_entry_rcu(ptype, &skb->dev->ptype_all, list) { 5958 if (pt_prev) 5959 ret = deliver_skb(skb, pt_prev, orig_dev); 5960 pt_prev = ptype; 5961 } 5962 5963 skip_taps: 5964 #ifdef CONFIG_NET_INGRESS 5965 if (static_branch_unlikely(&ingress_needed_key)) { 5966 bool another = false; 5967 5968 nf_skip_egress(skb, true); 5969 skb = sch_handle_ingress(skb, &pt_prev, &ret, orig_dev, 5970 &another); 5971 if (another) 5972 goto another_round; 5973 if (!skb) 5974 goto out; 5975 5976 nf_skip_egress(skb, false); 5977 if (nf_ingress(skb, &pt_prev, &ret, orig_dev) < 0) 5978 goto out; 5979 } 5980 #endif 5981 skb_reset_redirect(skb); 5982 skip_classify: 5983 if (pfmemalloc && !skb_pfmemalloc_protocol(skb)) { 5984 drop_reason = SKB_DROP_REASON_PFMEMALLOC; 5985 goto drop; 5986 } 5987 5988 if (skb_vlan_tag_present(skb)) { 5989 if (pt_prev) { 5990 ret = deliver_skb(skb, pt_prev, orig_dev); 5991 pt_prev = NULL; 5992 } 5993 if (vlan_do_receive(&skb)) 5994 goto another_round; 5995 else if (unlikely(!skb)) 5996 goto out; 5997 } 5998 5999 rx_handler = rcu_dereference(skb->dev->rx_handler); 6000 if (rx_handler) { 6001 if (pt_prev) { 6002 ret = deliver_skb(skb, pt_prev, orig_dev); 6003 pt_prev = NULL; 6004 } 6005 switch (rx_handler(&skb)) { 6006 case RX_HANDLER_CONSUMED: 6007 ret = NET_RX_SUCCESS; 6008 goto out; 6009 case RX_HANDLER_ANOTHER: 6010 goto another_round; 6011 case RX_HANDLER_EXACT: 6012 deliver_exact = true; 6013 break; 6014 case RX_HANDLER_PASS: 6015 break; 6016 default: 6017 BUG(); 6018 } 6019 } 6020 6021 if (unlikely(skb_vlan_tag_present(skb)) && !netdev_uses_dsa(skb->dev)) { 6022 check_vlan_id: 6023 if (skb_vlan_tag_get_id(skb)) { 6024 /* Vlan id is non 0 and vlan_do_receive() above couldn't 6025 * find vlan device. 6026 */ 6027 skb->pkt_type = PACKET_OTHERHOST; 6028 } else if (eth_type_vlan(skb->protocol)) { 6029 /* Outer header is 802.1P with vlan 0, inner header is 6030 * 802.1Q or 802.1AD and vlan_do_receive() above could 6031 * not find vlan dev for vlan id 0. 6032 */ 6033 __vlan_hwaccel_clear_tag(skb); 6034 skb = skb_vlan_untag(skb); 6035 if (unlikely(!skb)) 6036 goto out; 6037 if (vlan_do_receive(&skb)) 6038 /* After stripping off 802.1P header with vlan 0 6039 * vlan dev is found for inner header. 6040 */ 6041 goto another_round; 6042 else if (unlikely(!skb)) 6043 goto out; 6044 else 6045 /* We have stripped outer 802.1P vlan 0 header. 6046 * But could not find vlan dev. 6047 * check again for vlan id to set OTHERHOST. 6048 */ 6049 goto check_vlan_id; 6050 } 6051 /* Note: we might in the future use prio bits 6052 * and set skb->priority like in vlan_do_receive() 6053 * For the time being, just ignore Priority Code Point 6054 */ 6055 __vlan_hwaccel_clear_tag(skb); 6056 } 6057 6058 type = skb->protocol; 6059 6060 /* deliver only exact match when indicated */ 6061 if (likely(!deliver_exact)) { 6062 deliver_ptype_list_skb(skb, &pt_prev, orig_dev, type, 6063 &ptype_base[ntohs(type) & 6064 PTYPE_HASH_MASK]); 6065 6066 /* orig_dev and skb->dev could belong to different netns; 6067 * Even in such case we need to traverse only the list 6068 * coming from skb->dev, as the ptype owner (packet socket) 6069 * will use dev_net(skb->dev) to do namespace filtering. 6070 */ 6071 deliver_ptype_list_skb(skb, &pt_prev, orig_dev, type, 6072 &dev_net_rcu(skb->dev)->ptype_specific); 6073 } 6074 6075 deliver_ptype_list_skb(skb, &pt_prev, orig_dev, type, 6076 &orig_dev->ptype_specific); 6077 6078 if (unlikely(skb->dev != orig_dev)) { 6079 deliver_ptype_list_skb(skb, &pt_prev, orig_dev, type, 6080 &skb->dev->ptype_specific); 6081 } 6082 6083 if (pt_prev) { 6084 *ppt_prev = pt_prev; 6085 } else { 6086 drop: 6087 if (!deliver_exact) 6088 dev_core_stats_rx_dropped_inc(skb->dev); 6089 else 6090 dev_core_stats_rx_nohandler_inc(skb->dev); 6091 6092 kfree_skb_reason(skb, drop_reason); 6093 /* Jamal, now you will not able to escape explaining 6094 * me how you were going to use this. :-) 6095 */ 6096 ret = NET_RX_DROP; 6097 } 6098 6099 out: 6100 /* The invariant here is that if *ppt_prev is not NULL 6101 * then skb should also be non-NULL. 6102 * 6103 * Apparently *ppt_prev assignment above holds this invariant due to 6104 * skb dereferencing near it. 6105 */ 6106 *pskb = skb; 6107 return ret; 6108 } 6109 6110 static int __netif_receive_skb_one_core(struct sk_buff *skb, bool pfmemalloc) 6111 { 6112 struct net_device *orig_dev = skb->dev; 6113 struct packet_type *pt_prev = NULL; 6114 int ret; 6115 6116 ret = __netif_receive_skb_core(&skb, pfmemalloc, &pt_prev); 6117 if (pt_prev) 6118 ret = INDIRECT_CALL_INET(pt_prev->func, ipv6_rcv, ip_rcv, skb, 6119 skb->dev, pt_prev, orig_dev); 6120 return ret; 6121 } 6122 6123 /** 6124 * netif_receive_skb_core - special purpose version of netif_receive_skb 6125 * @skb: buffer to process 6126 * 6127 * More direct receive version of netif_receive_skb(). It should 6128 * only be used by callers that have a need to skip RPS and Generic XDP. 6129 * Caller must also take care of handling if ``(page_is_)pfmemalloc``. 6130 * 6131 * This function may only be called from softirq context and interrupts 6132 * should be enabled. 6133 * 6134 * Return values (usually ignored): 6135 * NET_RX_SUCCESS: no congestion 6136 * NET_RX_DROP: packet was dropped 6137 */ 6138 int netif_receive_skb_core(struct sk_buff *skb) 6139 { 6140 int ret; 6141 6142 rcu_read_lock(); 6143 ret = __netif_receive_skb_one_core(skb, false); 6144 rcu_read_unlock(); 6145 6146 return ret; 6147 } 6148 EXPORT_SYMBOL(netif_receive_skb_core); 6149 6150 static inline void __netif_receive_skb_list_ptype(struct list_head *head, 6151 struct packet_type *pt_prev, 6152 struct net_device *orig_dev) 6153 { 6154 struct sk_buff *skb, *next; 6155 6156 if (!pt_prev) 6157 return; 6158 if (list_empty(head)) 6159 return; 6160 if (pt_prev->list_func != NULL) 6161 INDIRECT_CALL_INET(pt_prev->list_func, ipv6_list_rcv, 6162 ip_list_rcv, head, pt_prev, orig_dev); 6163 else 6164 list_for_each_entry_safe(skb, next, head, list) { 6165 skb_list_del_init(skb); 6166 pt_prev->func(skb, skb->dev, pt_prev, orig_dev); 6167 } 6168 } 6169 6170 static void __netif_receive_skb_list_core(struct list_head *head, bool pfmemalloc) 6171 { 6172 /* Fast-path assumptions: 6173 * - There is no RX handler. 6174 * - Only one packet_type matches. 6175 * If either of these fails, we will end up doing some per-packet 6176 * processing in-line, then handling the 'last ptype' for the whole 6177 * sublist. This can't cause out-of-order delivery to any single ptype, 6178 * because the 'last ptype' must be constant across the sublist, and all 6179 * other ptypes are handled per-packet. 6180 */ 6181 /* Current (common) ptype of sublist */ 6182 struct packet_type *pt_curr = NULL; 6183 /* Current (common) orig_dev of sublist */ 6184 struct net_device *od_curr = NULL; 6185 struct sk_buff *skb, *next; 6186 LIST_HEAD(sublist); 6187 6188 list_for_each_entry_safe(skb, next, head, list) { 6189 struct net_device *orig_dev = skb->dev; 6190 struct packet_type *pt_prev = NULL; 6191 6192 skb_list_del_init(skb); 6193 __netif_receive_skb_core(&skb, pfmemalloc, &pt_prev); 6194 if (!pt_prev) 6195 continue; 6196 if (pt_curr != pt_prev || od_curr != orig_dev) { 6197 /* dispatch old sublist */ 6198 __netif_receive_skb_list_ptype(&sublist, pt_curr, od_curr); 6199 /* start new sublist */ 6200 INIT_LIST_HEAD(&sublist); 6201 pt_curr = pt_prev; 6202 od_curr = orig_dev; 6203 } 6204 list_add_tail(&skb->list, &sublist); 6205 } 6206 6207 /* dispatch final sublist */ 6208 __netif_receive_skb_list_ptype(&sublist, pt_curr, od_curr); 6209 } 6210 6211 static int __netif_receive_skb(struct sk_buff *skb) 6212 { 6213 int ret; 6214 6215 if (sk_memalloc_socks() && skb_pfmemalloc(skb)) { 6216 unsigned int noreclaim_flag; 6217 6218 /* 6219 * PFMEMALLOC skbs are special, they should 6220 * - be delivered to SOCK_MEMALLOC sockets only 6221 * - stay away from userspace 6222 * - have bounded memory usage 6223 * 6224 * Use PF_MEMALLOC as this saves us from propagating the allocation 6225 * context down to all allocation sites. 6226 */ 6227 noreclaim_flag = memalloc_noreclaim_save(); 6228 ret = __netif_receive_skb_one_core(skb, true); 6229 memalloc_noreclaim_restore(noreclaim_flag); 6230 } else 6231 ret = __netif_receive_skb_one_core(skb, false); 6232 6233 return ret; 6234 } 6235 6236 static void __netif_receive_skb_list(struct list_head *head) 6237 { 6238 unsigned long noreclaim_flag = 0; 6239 struct sk_buff *skb, *next; 6240 bool pfmemalloc = false; /* Is current sublist PF_MEMALLOC? */ 6241 6242 list_for_each_entry_safe(skb, next, head, list) { 6243 if ((sk_memalloc_socks() && skb_pfmemalloc(skb)) != pfmemalloc) { 6244 struct list_head sublist; 6245 6246 /* Handle the previous sublist */ 6247 list_cut_before(&sublist, head, &skb->list); 6248 if (!list_empty(&sublist)) 6249 __netif_receive_skb_list_core(&sublist, pfmemalloc); 6250 pfmemalloc = !pfmemalloc; 6251 /* See comments in __netif_receive_skb */ 6252 if (pfmemalloc) 6253 noreclaim_flag = memalloc_noreclaim_save(); 6254 else 6255 memalloc_noreclaim_restore(noreclaim_flag); 6256 } 6257 } 6258 /* Handle the remaining sublist */ 6259 if (!list_empty(head)) 6260 __netif_receive_skb_list_core(head, pfmemalloc); 6261 /* Restore pflags */ 6262 if (pfmemalloc) 6263 memalloc_noreclaim_restore(noreclaim_flag); 6264 } 6265 6266 static int generic_xdp_install(struct net_device *dev, struct netdev_bpf *xdp) 6267 { 6268 struct bpf_prog *old = rtnl_dereference(dev->xdp_prog); 6269 struct bpf_prog *new = xdp->prog; 6270 int ret = 0; 6271 6272 switch (xdp->command) { 6273 case XDP_SETUP_PROG: 6274 rcu_assign_pointer(dev->xdp_prog, new); 6275 if (old) 6276 bpf_prog_put(old); 6277 6278 if (old && !new) { 6279 static_branch_dec(&generic_xdp_needed_key); 6280 } else if (new && !old) { 6281 static_branch_inc(&generic_xdp_needed_key); 6282 netif_disable_lro(dev); 6283 dev_disable_gro_hw(dev); 6284 } 6285 break; 6286 6287 default: 6288 ret = -EINVAL; 6289 break; 6290 } 6291 6292 return ret; 6293 } 6294 6295 static int netif_receive_skb_internal(struct sk_buff *skb) 6296 { 6297 int ret; 6298 6299 net_timestamp_check(READ_ONCE(net_hotdata.tstamp_prequeue), skb); 6300 6301 if (skb_defer_rx_timestamp(skb)) 6302 return NET_RX_SUCCESS; 6303 6304 rcu_read_lock(); 6305 #ifdef CONFIG_RPS 6306 if (static_branch_unlikely(&rps_needed)) { 6307 struct rps_dev_flow voidflow, *rflow = &voidflow; 6308 int cpu = get_rps_cpu(skb->dev, skb, &rflow); 6309 6310 if (cpu >= 0) { 6311 ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail); 6312 rcu_read_unlock(); 6313 return ret; 6314 } 6315 } 6316 #endif 6317 ret = __netif_receive_skb(skb); 6318 rcu_read_unlock(); 6319 return ret; 6320 } 6321 6322 void netif_receive_skb_list_internal(struct list_head *head) 6323 { 6324 struct sk_buff *skb, *next; 6325 LIST_HEAD(sublist); 6326 6327 list_for_each_entry_safe(skb, next, head, list) { 6328 net_timestamp_check(READ_ONCE(net_hotdata.tstamp_prequeue), 6329 skb); 6330 skb_list_del_init(skb); 6331 if (!skb_defer_rx_timestamp(skb)) 6332 list_add_tail(&skb->list, &sublist); 6333 } 6334 list_splice_init(&sublist, head); 6335 6336 rcu_read_lock(); 6337 #ifdef CONFIG_RPS 6338 if (static_branch_unlikely(&rps_needed)) { 6339 list_for_each_entry_safe(skb, next, head, list) { 6340 struct rps_dev_flow voidflow, *rflow = &voidflow; 6341 int cpu = get_rps_cpu(skb->dev, skb, &rflow); 6342 6343 if (cpu >= 0) { 6344 /* Will be handled, remove from list */ 6345 skb_list_del_init(skb); 6346 enqueue_to_backlog(skb, cpu, &rflow->last_qtail); 6347 } 6348 } 6349 } 6350 #endif 6351 __netif_receive_skb_list(head); 6352 rcu_read_unlock(); 6353 } 6354 6355 /** 6356 * netif_receive_skb - process receive buffer from network 6357 * @skb: buffer to process 6358 * 6359 * netif_receive_skb() is the main receive data processing function. 6360 * It always succeeds. The buffer may be dropped during processing 6361 * for congestion control or by the protocol layers. 6362 * 6363 * This function may only be called from softirq context and interrupts 6364 * should be enabled. 6365 * 6366 * Return values (usually ignored): 6367 * NET_RX_SUCCESS: no congestion 6368 * NET_RX_DROP: packet was dropped 6369 */ 6370 int netif_receive_skb(struct sk_buff *skb) 6371 { 6372 int ret; 6373 6374 trace_netif_receive_skb_entry(skb); 6375 6376 ret = netif_receive_skb_internal(skb); 6377 trace_netif_receive_skb_exit(ret); 6378 6379 return ret; 6380 } 6381 EXPORT_SYMBOL(netif_receive_skb); 6382 6383 /** 6384 * netif_receive_skb_list - process many receive buffers from network 6385 * @head: list of skbs to process. 6386 * 6387 * Since return value of netif_receive_skb() is normally ignored, and 6388 * wouldn't be meaningful for a list, this function returns void. 6389 * 6390 * This function may only be called from softirq context and interrupts 6391 * should be enabled. 6392 */ 6393 void netif_receive_skb_list(struct list_head *head) 6394 { 6395 struct sk_buff *skb; 6396 6397 if (list_empty(head)) 6398 return; 6399 if (trace_netif_receive_skb_list_entry_enabled()) { 6400 list_for_each_entry(skb, head, list) 6401 trace_netif_receive_skb_list_entry(skb); 6402 } 6403 netif_receive_skb_list_internal(head); 6404 trace_netif_receive_skb_list_exit(0); 6405 } 6406 EXPORT_SYMBOL(netif_receive_skb_list); 6407 6408 /* Network device is going away, flush any packets still pending */ 6409 static void flush_backlog(struct work_struct *work) 6410 { 6411 struct sk_buff *skb, *tmp; 6412 struct sk_buff_head list; 6413 struct softnet_data *sd; 6414 6415 __skb_queue_head_init(&list); 6416 local_bh_disable(); 6417 sd = this_cpu_ptr(&softnet_data); 6418 6419 backlog_lock_irq_disable(sd); 6420 skb_queue_walk_safe(&sd->input_pkt_queue, skb, tmp) { 6421 if (READ_ONCE(skb->dev->reg_state) == NETREG_UNREGISTERING) { 6422 __skb_unlink(skb, &sd->input_pkt_queue); 6423 __skb_queue_tail(&list, skb); 6424 rps_input_queue_head_incr(sd); 6425 } 6426 } 6427 backlog_unlock_irq_enable(sd); 6428 6429 local_lock_nested_bh(&softnet_data.process_queue_bh_lock); 6430 skb_queue_walk_safe(&sd->process_queue, skb, tmp) { 6431 if (READ_ONCE(skb->dev->reg_state) == NETREG_UNREGISTERING) { 6432 __skb_unlink(skb, &sd->process_queue); 6433 __skb_queue_tail(&list, skb); 6434 rps_input_queue_head_incr(sd); 6435 } 6436 } 6437 local_unlock_nested_bh(&softnet_data.process_queue_bh_lock); 6438 local_bh_enable(); 6439 6440 __skb_queue_purge_reason(&list, SKB_DROP_REASON_DEV_READY); 6441 } 6442 6443 static bool flush_required(int cpu) 6444 { 6445 #if IS_ENABLED(CONFIG_RPS) 6446 struct softnet_data *sd = &per_cpu(softnet_data, cpu); 6447 bool do_flush; 6448 6449 backlog_lock_irq_disable(sd); 6450 6451 /* as insertion into process_queue happens with the rps lock held, 6452 * process_queue access may race only with dequeue 6453 */ 6454 do_flush = !skb_queue_empty(&sd->input_pkt_queue) || 6455 !skb_queue_empty_lockless(&sd->process_queue); 6456 backlog_unlock_irq_enable(sd); 6457 6458 return do_flush; 6459 #endif 6460 /* without RPS we can't safely check input_pkt_queue: during a 6461 * concurrent remote skb_queue_splice() we can detect as empty both 6462 * input_pkt_queue and process_queue even if the latter could end-up 6463 * containing a lot of packets. 6464 */ 6465 return true; 6466 } 6467 6468 struct flush_backlogs { 6469 cpumask_t flush_cpus; 6470 struct work_struct w[]; 6471 }; 6472 6473 static struct flush_backlogs *flush_backlogs_alloc(void) 6474 { 6475 return kmalloc(struct_size_t(struct flush_backlogs, w, nr_cpu_ids), 6476 GFP_KERNEL); 6477 } 6478 6479 static struct flush_backlogs *flush_backlogs_fallback; 6480 static DEFINE_MUTEX(flush_backlogs_mutex); 6481 6482 static void flush_all_backlogs(void) 6483 { 6484 struct flush_backlogs *ptr = flush_backlogs_alloc(); 6485 unsigned int cpu; 6486 6487 if (!ptr) { 6488 mutex_lock(&flush_backlogs_mutex); 6489 ptr = flush_backlogs_fallback; 6490 } 6491 cpumask_clear(&ptr->flush_cpus); 6492 6493 cpus_read_lock(); 6494 6495 for_each_online_cpu(cpu) { 6496 if (flush_required(cpu)) { 6497 INIT_WORK(&ptr->w[cpu], flush_backlog); 6498 queue_work_on(cpu, system_highpri_wq, &ptr->w[cpu]); 6499 __cpumask_set_cpu(cpu, &ptr->flush_cpus); 6500 } 6501 } 6502 6503 /* we can have in flight packet[s] on the cpus we are not flushing, 6504 * synchronize_net() in unregister_netdevice_many() will take care of 6505 * them. 6506 */ 6507 for_each_cpu(cpu, &ptr->flush_cpus) 6508 flush_work(&ptr->w[cpu]); 6509 6510 cpus_read_unlock(); 6511 6512 if (ptr != flush_backlogs_fallback) 6513 kfree(ptr); 6514 else 6515 mutex_unlock(&flush_backlogs_mutex); 6516 } 6517 6518 static void net_rps_send_ipi(struct softnet_data *remsd) 6519 { 6520 #ifdef CONFIG_RPS 6521 while (remsd) { 6522 struct softnet_data *next = remsd->rps_ipi_next; 6523 6524 if (cpu_online(remsd->cpu)) 6525 smp_call_function_single_async(remsd->cpu, &remsd->csd); 6526 remsd = next; 6527 } 6528 #endif 6529 } 6530 6531 /* 6532 * net_rps_action_and_irq_enable sends any pending IPI's for rps. 6533 * Note: called with local irq disabled, but exits with local irq enabled. 6534 */ 6535 static void net_rps_action_and_irq_enable(struct softnet_data *sd) 6536 { 6537 #ifdef CONFIG_RPS 6538 struct softnet_data *remsd = sd->rps_ipi_list; 6539 6540 if (!use_backlog_threads() && remsd) { 6541 sd->rps_ipi_list = NULL; 6542 6543 local_irq_enable(); 6544 6545 /* Send pending IPI's to kick RPS processing on remote cpus. */ 6546 net_rps_send_ipi(remsd); 6547 } else 6548 #endif 6549 local_irq_enable(); 6550 } 6551 6552 static bool sd_has_rps_ipi_waiting(struct softnet_data *sd) 6553 { 6554 #ifdef CONFIG_RPS 6555 return !use_backlog_threads() && sd->rps_ipi_list; 6556 #else 6557 return false; 6558 #endif 6559 } 6560 6561 static int process_backlog(struct napi_struct *napi, int quota) 6562 { 6563 struct softnet_data *sd = container_of(napi, struct softnet_data, backlog); 6564 bool again = true; 6565 int work = 0; 6566 6567 /* Check if we have pending ipi, its better to send them now, 6568 * not waiting net_rx_action() end. 6569 */ 6570 if (sd_has_rps_ipi_waiting(sd)) { 6571 local_irq_disable(); 6572 net_rps_action_and_irq_enable(sd); 6573 } 6574 6575 napi->weight = READ_ONCE(net_hotdata.dev_rx_weight); 6576 while (again) { 6577 struct sk_buff *skb; 6578 6579 local_lock_nested_bh(&softnet_data.process_queue_bh_lock); 6580 while ((skb = __skb_dequeue(&sd->process_queue))) { 6581 local_unlock_nested_bh(&softnet_data.process_queue_bh_lock); 6582 rcu_read_lock(); 6583 __netif_receive_skb(skb); 6584 rcu_read_unlock(); 6585 if (++work >= quota) { 6586 rps_input_queue_head_add(sd, work); 6587 return work; 6588 } 6589 6590 local_lock_nested_bh(&softnet_data.process_queue_bh_lock); 6591 } 6592 local_unlock_nested_bh(&softnet_data.process_queue_bh_lock); 6593 6594 backlog_lock_irq_disable(sd); 6595 if (skb_queue_empty(&sd->input_pkt_queue)) { 6596 /* 6597 * Inline a custom version of __napi_complete(). 6598 * only current cpu owns and manipulates this napi, 6599 * and NAPI_STATE_SCHED is the only possible flag set 6600 * on backlog. 6601 * We can use a plain write instead of clear_bit(), 6602 * and we dont need an smp_mb() memory barrier. 6603 */ 6604 napi->state &= NAPIF_STATE_THREADED; 6605 again = false; 6606 } else { 6607 local_lock_nested_bh(&softnet_data.process_queue_bh_lock); 6608 skb_queue_splice_tail_init(&sd->input_pkt_queue, 6609 &sd->process_queue); 6610 local_unlock_nested_bh(&softnet_data.process_queue_bh_lock); 6611 } 6612 backlog_unlock_irq_enable(sd); 6613 } 6614 6615 if (work) 6616 rps_input_queue_head_add(sd, work); 6617 return work; 6618 } 6619 6620 /** 6621 * __napi_schedule - schedule for receive 6622 * @n: entry to schedule 6623 * 6624 * The entry's receive function will be scheduled to run. 6625 * Consider using __napi_schedule_irqoff() if hard irqs are masked. 6626 */ 6627 void __napi_schedule(struct napi_struct *n) 6628 { 6629 unsigned long flags; 6630 6631 local_irq_save(flags); 6632 ____napi_schedule(this_cpu_ptr(&softnet_data), n); 6633 local_irq_restore(flags); 6634 } 6635 EXPORT_SYMBOL(__napi_schedule); 6636 6637 /** 6638 * napi_schedule_prep - check if napi can be scheduled 6639 * @n: napi context 6640 * 6641 * Test if NAPI routine is already running, and if not mark 6642 * it as running. This is used as a condition variable to 6643 * insure only one NAPI poll instance runs. We also make 6644 * sure there is no pending NAPI disable. 6645 */ 6646 bool napi_schedule_prep(struct napi_struct *n) 6647 { 6648 unsigned long new, val = READ_ONCE(n->state); 6649 6650 do { 6651 if (unlikely(val & NAPIF_STATE_DISABLE)) 6652 return false; 6653 new = val | NAPIF_STATE_SCHED; 6654 6655 /* Sets STATE_MISSED bit if STATE_SCHED was already set 6656 * This was suggested by Alexander Duyck, as compiler 6657 * emits better code than : 6658 * if (val & NAPIF_STATE_SCHED) 6659 * new |= NAPIF_STATE_MISSED; 6660 */ 6661 new |= (val & NAPIF_STATE_SCHED) / NAPIF_STATE_SCHED * 6662 NAPIF_STATE_MISSED; 6663 } while (!try_cmpxchg(&n->state, &val, new)); 6664 6665 return !(val & NAPIF_STATE_SCHED); 6666 } 6667 EXPORT_SYMBOL(napi_schedule_prep); 6668 6669 /** 6670 * __napi_schedule_irqoff - schedule for receive 6671 * @n: entry to schedule 6672 * 6673 * Variant of __napi_schedule() assuming hard irqs are masked. 6674 * 6675 * On PREEMPT_RT enabled kernels this maps to __napi_schedule() 6676 * because the interrupt disabled assumption might not be true 6677 * due to force-threaded interrupts and spinlock substitution. 6678 */ 6679 void __napi_schedule_irqoff(struct napi_struct *n) 6680 { 6681 if (!IS_ENABLED(CONFIG_PREEMPT_RT)) 6682 ____napi_schedule(this_cpu_ptr(&softnet_data), n); 6683 else 6684 __napi_schedule(n); 6685 } 6686 EXPORT_SYMBOL(__napi_schedule_irqoff); 6687 6688 bool napi_complete_done(struct napi_struct *n, int work_done) 6689 { 6690 unsigned long flags, val, new, timeout = 0; 6691 bool ret = true; 6692 6693 /* 6694 * 1) Don't let napi dequeue from the cpu poll list 6695 * just in case its running on a different cpu. 6696 * 2) If we are busy polling, do nothing here, we have 6697 * the guarantee we will be called later. 6698 */ 6699 if (unlikely(n->state & (NAPIF_STATE_NPSVC | 6700 NAPIF_STATE_IN_BUSY_POLL))) 6701 return false; 6702 6703 if (work_done) { 6704 if (n->gro.bitmask) 6705 timeout = napi_get_gro_flush_timeout(n); 6706 n->defer_hard_irqs_count = napi_get_defer_hard_irqs(n); 6707 } 6708 if (n->defer_hard_irqs_count > 0) { 6709 n->defer_hard_irqs_count--; 6710 timeout = napi_get_gro_flush_timeout(n); 6711 if (timeout) 6712 ret = false; 6713 } 6714 6715 /* 6716 * When the NAPI instance uses a timeout and keeps postponing 6717 * it, we need to bound somehow the time packets are kept in 6718 * the GRO layer. 6719 */ 6720 gro_flush_normal(&n->gro, !!timeout); 6721 6722 if (unlikely(!list_empty(&n->poll_list))) { 6723 /* If n->poll_list is not empty, we need to mask irqs */ 6724 local_irq_save(flags); 6725 list_del_init(&n->poll_list); 6726 local_irq_restore(flags); 6727 } 6728 WRITE_ONCE(n->list_owner, -1); 6729 6730 val = READ_ONCE(n->state); 6731 do { 6732 WARN_ON_ONCE(!(val & NAPIF_STATE_SCHED)); 6733 6734 new = val & ~(NAPIF_STATE_MISSED | NAPIF_STATE_SCHED | 6735 NAPIF_STATE_SCHED_THREADED | 6736 NAPIF_STATE_PREFER_BUSY_POLL); 6737 6738 /* If STATE_MISSED was set, leave STATE_SCHED set, 6739 * because we will call napi->poll() one more time. 6740 * This C code was suggested by Alexander Duyck to help gcc. 6741 */ 6742 new |= (val & NAPIF_STATE_MISSED) / NAPIF_STATE_MISSED * 6743 NAPIF_STATE_SCHED; 6744 } while (!try_cmpxchg(&n->state, &val, new)); 6745 6746 if (unlikely(val & NAPIF_STATE_MISSED)) { 6747 __napi_schedule(n); 6748 return false; 6749 } 6750 6751 if (timeout) 6752 hrtimer_start(&n->timer, ns_to_ktime(timeout), 6753 HRTIMER_MODE_REL_PINNED); 6754 return ret; 6755 } 6756 EXPORT_SYMBOL(napi_complete_done); 6757 6758 static void skb_defer_free_flush(void) 6759 { 6760 struct llist_node *free_list; 6761 struct sk_buff *skb, *next; 6762 struct skb_defer_node *sdn; 6763 int node; 6764 6765 for_each_node(node) { 6766 sdn = this_cpu_ptr(net_hotdata.skb_defer_nodes) + node; 6767 6768 if (llist_empty(&sdn->defer_list)) 6769 continue; 6770 atomic_long_set(&sdn->defer_count, 0); 6771 free_list = llist_del_all(&sdn->defer_list); 6772 6773 llist_for_each_entry_safe(skb, next, free_list, ll_node) { 6774 napi_consume_skb(skb, 1); 6775 } 6776 } 6777 } 6778 6779 #if defined(CONFIG_NET_RX_BUSY_POLL) 6780 6781 static void __busy_poll_stop(struct napi_struct *napi, unsigned long timeout) 6782 { 6783 if (!timeout) { 6784 gro_normal_list(&napi->gro); 6785 __napi_schedule(napi); 6786 return; 6787 } 6788 6789 /* Flush too old packets. If HZ < 1000, flush all packets */ 6790 gro_flush_normal(&napi->gro, HZ >= 1000); 6791 6792 clear_bit(NAPI_STATE_SCHED, &napi->state); 6793 hrtimer_start(&napi->timer, ns_to_ktime(timeout), 6794 HRTIMER_MODE_REL_PINNED); 6795 } 6796 6797 enum { 6798 NAPI_F_PREFER_BUSY_POLL = 1, 6799 NAPI_F_END_ON_RESCHED = 2, 6800 }; 6801 6802 static void busy_poll_stop(struct napi_struct *napi, void *have_poll_lock, 6803 unsigned flags, u16 budget) 6804 { 6805 struct bpf_net_context __bpf_net_ctx, *bpf_net_ctx; 6806 unsigned long timeout = 0; 6807 int rc; 6808 6809 /* Busy polling means there is a high chance device driver hard irq 6810 * could not grab NAPI_STATE_SCHED, and that NAPI_STATE_MISSED was 6811 * set in napi_schedule_prep(). 6812 * Since we are about to call napi->poll() once more, we can safely 6813 * clear NAPI_STATE_MISSED. 6814 * 6815 * Note: x86 could use a single "lock and ..." instruction 6816 * to perform these two clear_bit() 6817 */ 6818 clear_bit(NAPI_STATE_MISSED, &napi->state); 6819 clear_bit(NAPI_STATE_IN_BUSY_POLL, &napi->state); 6820 6821 local_bh_disable(); 6822 bpf_net_ctx = bpf_net_ctx_set(&__bpf_net_ctx); 6823 6824 if (flags & NAPI_F_PREFER_BUSY_POLL) { 6825 napi->defer_hard_irqs_count = napi_get_defer_hard_irqs(napi); 6826 if (napi->defer_hard_irqs_count) { 6827 /* A short enough gro flush timeout and long enough 6828 * poll can result in timer firing too early. 6829 * Timer will be armed later if necessary. 6830 */ 6831 timeout = napi_get_gro_flush_timeout(napi); 6832 } 6833 } 6834 6835 /* All we really want here is to re-enable device interrupts. 6836 * Ideally, a new ndo_busy_poll_stop() could avoid another round. 6837 */ 6838 rc = napi->poll(napi, budget); 6839 /* We can't gro_normal_list() here, because napi->poll() might have 6840 * rearmed the napi (napi_complete_done()) in which case it could 6841 * already be running on another CPU. 6842 */ 6843 trace_napi_poll(napi, rc, budget); 6844 netpoll_poll_unlock(have_poll_lock); 6845 if (rc == budget) 6846 __busy_poll_stop(napi, timeout); 6847 bpf_net_ctx_clear(bpf_net_ctx); 6848 local_bh_enable(); 6849 } 6850 6851 static void __napi_busy_loop(unsigned int napi_id, 6852 bool (*loop_end)(void *, unsigned long), 6853 void *loop_end_arg, unsigned flags, u16 budget) 6854 { 6855 unsigned long start_time = loop_end ? busy_loop_current_time() : 0; 6856 int (*napi_poll)(struct napi_struct *napi, int budget); 6857 struct bpf_net_context __bpf_net_ctx, *bpf_net_ctx; 6858 void *have_poll_lock = NULL; 6859 struct napi_struct *napi; 6860 6861 WARN_ON_ONCE(!rcu_read_lock_held()); 6862 6863 restart: 6864 napi_poll = NULL; 6865 6866 napi = napi_by_id(napi_id); 6867 if (!napi) 6868 return; 6869 6870 if (!IS_ENABLED(CONFIG_PREEMPT_RT)) 6871 preempt_disable(); 6872 for (;;) { 6873 int work = 0; 6874 6875 local_bh_disable(); 6876 bpf_net_ctx = bpf_net_ctx_set(&__bpf_net_ctx); 6877 if (!napi_poll) { 6878 unsigned long val = READ_ONCE(napi->state); 6879 6880 /* If multiple threads are competing for this napi, 6881 * we avoid dirtying napi->state as much as we can. 6882 */ 6883 if (val & (NAPIF_STATE_DISABLE | NAPIF_STATE_SCHED | 6884 NAPIF_STATE_IN_BUSY_POLL)) { 6885 if (flags & NAPI_F_PREFER_BUSY_POLL) 6886 set_bit(NAPI_STATE_PREFER_BUSY_POLL, &napi->state); 6887 goto count; 6888 } 6889 if (cmpxchg(&napi->state, val, 6890 val | NAPIF_STATE_IN_BUSY_POLL | 6891 NAPIF_STATE_SCHED) != val) { 6892 if (flags & NAPI_F_PREFER_BUSY_POLL) 6893 set_bit(NAPI_STATE_PREFER_BUSY_POLL, &napi->state); 6894 goto count; 6895 } 6896 have_poll_lock = netpoll_poll_lock(napi); 6897 napi_poll = napi->poll; 6898 } 6899 work = napi_poll(napi, budget); 6900 trace_napi_poll(napi, work, budget); 6901 gro_normal_list(&napi->gro); 6902 count: 6903 if (work > 0) 6904 __NET_ADD_STATS(dev_net(napi->dev), 6905 LINUX_MIB_BUSYPOLLRXPACKETS, work); 6906 skb_defer_free_flush(); 6907 bpf_net_ctx_clear(bpf_net_ctx); 6908 local_bh_enable(); 6909 6910 if (!loop_end || loop_end(loop_end_arg, start_time)) 6911 break; 6912 6913 if (unlikely(need_resched())) { 6914 if (flags & NAPI_F_END_ON_RESCHED) 6915 break; 6916 if (napi_poll) 6917 busy_poll_stop(napi, have_poll_lock, flags, budget); 6918 if (!IS_ENABLED(CONFIG_PREEMPT_RT)) 6919 preempt_enable(); 6920 rcu_read_unlock(); 6921 cond_resched(); 6922 rcu_read_lock(); 6923 if (loop_end(loop_end_arg, start_time)) 6924 return; 6925 goto restart; 6926 } 6927 cpu_relax(); 6928 } 6929 if (napi_poll) 6930 busy_poll_stop(napi, have_poll_lock, flags, budget); 6931 if (!IS_ENABLED(CONFIG_PREEMPT_RT)) 6932 preempt_enable(); 6933 } 6934 6935 void napi_busy_loop_rcu(unsigned int napi_id, 6936 bool (*loop_end)(void *, unsigned long), 6937 void *loop_end_arg, bool prefer_busy_poll, u16 budget) 6938 { 6939 unsigned flags = NAPI_F_END_ON_RESCHED; 6940 6941 if (prefer_busy_poll) 6942 flags |= NAPI_F_PREFER_BUSY_POLL; 6943 6944 __napi_busy_loop(napi_id, loop_end, loop_end_arg, flags, budget); 6945 } 6946 6947 void napi_busy_loop(unsigned int napi_id, 6948 bool (*loop_end)(void *, unsigned long), 6949 void *loop_end_arg, bool prefer_busy_poll, u16 budget) 6950 { 6951 unsigned flags = prefer_busy_poll ? NAPI_F_PREFER_BUSY_POLL : 0; 6952 6953 rcu_read_lock(); 6954 __napi_busy_loop(napi_id, loop_end, loop_end_arg, flags, budget); 6955 rcu_read_unlock(); 6956 } 6957 EXPORT_SYMBOL(napi_busy_loop); 6958 6959 void napi_suspend_irqs(unsigned int napi_id) 6960 { 6961 struct napi_struct *napi; 6962 6963 rcu_read_lock(); 6964 napi = napi_by_id(napi_id); 6965 if (napi) { 6966 unsigned long timeout = napi_get_irq_suspend_timeout(napi); 6967 6968 if (timeout) 6969 hrtimer_start(&napi->timer, ns_to_ktime(timeout), 6970 HRTIMER_MODE_REL_PINNED); 6971 } 6972 rcu_read_unlock(); 6973 } 6974 6975 void napi_resume_irqs(unsigned int napi_id) 6976 { 6977 struct napi_struct *napi; 6978 6979 rcu_read_lock(); 6980 napi = napi_by_id(napi_id); 6981 if (napi) { 6982 /* If irq_suspend_timeout is set to 0 between the call to 6983 * napi_suspend_irqs and now, the original value still 6984 * determines the safety timeout as intended and napi_watchdog 6985 * will resume irq processing. 6986 */ 6987 if (napi_get_irq_suspend_timeout(napi)) { 6988 local_bh_disable(); 6989 napi_schedule(napi); 6990 local_bh_enable(); 6991 } 6992 } 6993 rcu_read_unlock(); 6994 } 6995 6996 #endif /* CONFIG_NET_RX_BUSY_POLL */ 6997 6998 static void __napi_hash_add_with_id(struct napi_struct *napi, 6999 unsigned int napi_id) 7000 { 7001 napi->gro.cached_napi_id = napi_id; 7002 7003 WRITE_ONCE(napi->napi_id, napi_id); 7004 hlist_add_head_rcu(&napi->napi_hash_node, 7005 &napi_hash[napi->napi_id % HASH_SIZE(napi_hash)]); 7006 } 7007 7008 static void napi_hash_add_with_id(struct napi_struct *napi, 7009 unsigned int napi_id) 7010 { 7011 unsigned long flags; 7012 7013 spin_lock_irqsave(&napi_hash_lock, flags); 7014 WARN_ON_ONCE(napi_by_id(napi_id)); 7015 __napi_hash_add_with_id(napi, napi_id); 7016 spin_unlock_irqrestore(&napi_hash_lock, flags); 7017 } 7018 7019 static void napi_hash_add(struct napi_struct *napi) 7020 { 7021 unsigned long flags; 7022 7023 if (test_bit(NAPI_STATE_NO_BUSY_POLL, &napi->state)) 7024 return; 7025 7026 spin_lock_irqsave(&napi_hash_lock, flags); 7027 7028 /* 0..NR_CPUS range is reserved for sender_cpu use */ 7029 do { 7030 if (unlikely(!napi_id_valid(++napi_gen_id))) 7031 napi_gen_id = MIN_NAPI_ID; 7032 } while (napi_by_id(napi_gen_id)); 7033 7034 __napi_hash_add_with_id(napi, napi_gen_id); 7035 7036 spin_unlock_irqrestore(&napi_hash_lock, flags); 7037 } 7038 7039 /* Warning : caller is responsible to make sure rcu grace period 7040 * is respected before freeing memory containing @napi 7041 */ 7042 static void napi_hash_del(struct napi_struct *napi) 7043 { 7044 unsigned long flags; 7045 7046 spin_lock_irqsave(&napi_hash_lock, flags); 7047 7048 hlist_del_init_rcu(&napi->napi_hash_node); 7049 7050 spin_unlock_irqrestore(&napi_hash_lock, flags); 7051 } 7052 7053 static enum hrtimer_restart napi_watchdog(struct hrtimer *timer) 7054 { 7055 struct napi_struct *napi; 7056 7057 napi = container_of(timer, struct napi_struct, timer); 7058 7059 /* Note : we use a relaxed variant of napi_schedule_prep() not setting 7060 * NAPI_STATE_MISSED, since we do not react to a device IRQ. 7061 */ 7062 if (!napi_disable_pending(napi) && 7063 !test_and_set_bit(NAPI_STATE_SCHED, &napi->state)) { 7064 clear_bit(NAPI_STATE_PREFER_BUSY_POLL, &napi->state); 7065 __napi_schedule_irqoff(napi); 7066 } 7067 7068 return HRTIMER_NORESTART; 7069 } 7070 7071 static void napi_stop_kthread(struct napi_struct *napi) 7072 { 7073 unsigned long val, new; 7074 7075 /* Wait until the napi STATE_THREADED is unset. */ 7076 while (true) { 7077 val = READ_ONCE(napi->state); 7078 7079 /* If napi kthread own this napi or the napi is idle, 7080 * STATE_THREADED can be unset here. 7081 */ 7082 if ((val & NAPIF_STATE_SCHED_THREADED) || 7083 !(val & NAPIF_STATE_SCHED)) { 7084 new = val & (~NAPIF_STATE_THREADED); 7085 } else { 7086 msleep(20); 7087 continue; 7088 } 7089 7090 if (try_cmpxchg(&napi->state, &val, new)) 7091 break; 7092 } 7093 7094 /* Once STATE_THREADED is unset, wait for SCHED_THREADED to be unset by 7095 * the kthread. 7096 */ 7097 while (true) { 7098 if (!test_bit(NAPI_STATE_SCHED_THREADED, &napi->state)) 7099 break; 7100 7101 msleep(20); 7102 } 7103 7104 kthread_stop(napi->thread); 7105 napi->thread = NULL; 7106 } 7107 7108 int napi_set_threaded(struct napi_struct *napi, 7109 enum netdev_napi_threaded threaded) 7110 { 7111 if (threaded) { 7112 if (!napi->thread) { 7113 int err = napi_kthread_create(napi); 7114 7115 if (err) 7116 return err; 7117 } 7118 } 7119 7120 if (napi->config) 7121 napi->config->threaded = threaded; 7122 7123 /* Setting/unsetting threaded mode on a napi might not immediately 7124 * take effect, if the current napi instance is actively being 7125 * polled. In this case, the switch between threaded mode and 7126 * softirq mode will happen in the next round of napi_schedule(). 7127 * This should not cause hiccups/stalls to the live traffic. 7128 */ 7129 if (!threaded && napi->thread) { 7130 napi_stop_kthread(napi); 7131 } else { 7132 /* Make sure kthread is created before THREADED bit is set. */ 7133 smp_mb__before_atomic(); 7134 assign_bit(NAPI_STATE_THREADED, &napi->state, threaded); 7135 } 7136 7137 return 0; 7138 } 7139 7140 int netif_set_threaded(struct net_device *dev, 7141 enum netdev_napi_threaded threaded) 7142 { 7143 struct napi_struct *napi; 7144 int i, err = 0; 7145 7146 netdev_assert_locked_or_invisible(dev); 7147 7148 if (threaded) { 7149 list_for_each_entry(napi, &dev->napi_list, dev_list) { 7150 if (!napi->thread) { 7151 err = napi_kthread_create(napi); 7152 if (err) { 7153 threaded = NETDEV_NAPI_THREADED_DISABLED; 7154 break; 7155 } 7156 } 7157 } 7158 } 7159 7160 WRITE_ONCE(dev->threaded, threaded); 7161 7162 /* The error should not occur as the kthreads are already created. */ 7163 list_for_each_entry(napi, &dev->napi_list, dev_list) 7164 WARN_ON_ONCE(napi_set_threaded(napi, threaded)); 7165 7166 /* Override the config for all NAPIs even if currently not listed */ 7167 for (i = 0; i < dev->num_napi_configs; i++) 7168 dev->napi_config[i].threaded = threaded; 7169 7170 return err; 7171 } 7172 7173 /** 7174 * netif_threaded_enable() - enable threaded NAPIs 7175 * @dev: net_device instance 7176 * 7177 * Enable threaded mode for the NAPI instances of the device. This may be useful 7178 * for devices where multiple NAPI instances get scheduled by a single 7179 * interrupt. Threaded NAPI allows moving the NAPI processing to cores other 7180 * than the core where IRQ is mapped. 7181 * 7182 * This function should be called before @dev is registered. 7183 */ 7184 void netif_threaded_enable(struct net_device *dev) 7185 { 7186 WARN_ON_ONCE(netif_set_threaded(dev, NETDEV_NAPI_THREADED_ENABLED)); 7187 } 7188 EXPORT_SYMBOL(netif_threaded_enable); 7189 7190 /** 7191 * netif_queue_set_napi - Associate queue with the napi 7192 * @dev: device to which NAPI and queue belong 7193 * @queue_index: Index of queue 7194 * @type: queue type as RX or TX 7195 * @napi: NAPI context, pass NULL to clear previously set NAPI 7196 * 7197 * Set queue with its corresponding napi context. This should be done after 7198 * registering the NAPI handler for the queue-vector and the queues have been 7199 * mapped to the corresponding interrupt vector. 7200 */ 7201 void netif_queue_set_napi(struct net_device *dev, unsigned int queue_index, 7202 enum netdev_queue_type type, struct napi_struct *napi) 7203 { 7204 struct netdev_rx_queue *rxq; 7205 struct netdev_queue *txq; 7206 7207 if (WARN_ON_ONCE(napi && !napi->dev)) 7208 return; 7209 netdev_ops_assert_locked_or_invisible(dev); 7210 7211 switch (type) { 7212 case NETDEV_QUEUE_TYPE_RX: 7213 rxq = __netif_get_rx_queue(dev, queue_index); 7214 rxq->napi = napi; 7215 return; 7216 case NETDEV_QUEUE_TYPE_TX: 7217 txq = netdev_get_tx_queue(dev, queue_index); 7218 txq->napi = napi; 7219 return; 7220 default: 7221 return; 7222 } 7223 } 7224 EXPORT_SYMBOL(netif_queue_set_napi); 7225 7226 static void 7227 netif_napi_irq_notify(struct irq_affinity_notify *notify, 7228 const cpumask_t *mask) 7229 { 7230 struct napi_struct *napi = 7231 container_of(notify, struct napi_struct, notify); 7232 #ifdef CONFIG_RFS_ACCEL 7233 struct cpu_rmap *rmap = napi->dev->rx_cpu_rmap; 7234 int err; 7235 #endif 7236 7237 if (napi->config && napi->dev->irq_affinity_auto) 7238 cpumask_copy(&napi->config->affinity_mask, mask); 7239 7240 #ifdef CONFIG_RFS_ACCEL 7241 if (napi->dev->rx_cpu_rmap_auto) { 7242 err = cpu_rmap_update(rmap, napi->napi_rmap_idx, mask); 7243 if (err) 7244 netdev_warn(napi->dev, "RMAP update failed (%d)\n", 7245 err); 7246 } 7247 #endif 7248 } 7249 7250 #ifdef CONFIG_RFS_ACCEL 7251 static void netif_napi_affinity_release(struct kref *ref) 7252 { 7253 struct napi_struct *napi = 7254 container_of(ref, struct napi_struct, notify.kref); 7255 struct cpu_rmap *rmap = napi->dev->rx_cpu_rmap; 7256 7257 netdev_assert_locked(napi->dev); 7258 WARN_ON(test_and_clear_bit(NAPI_STATE_HAS_NOTIFIER, 7259 &napi->state)); 7260 7261 if (!napi->dev->rx_cpu_rmap_auto) 7262 return; 7263 rmap->obj[napi->napi_rmap_idx] = NULL; 7264 napi->napi_rmap_idx = -1; 7265 cpu_rmap_put(rmap); 7266 } 7267 7268 int netif_enable_cpu_rmap(struct net_device *dev, unsigned int num_irqs) 7269 { 7270 if (dev->rx_cpu_rmap_auto) 7271 return 0; 7272 7273 dev->rx_cpu_rmap = alloc_irq_cpu_rmap(num_irqs); 7274 if (!dev->rx_cpu_rmap) 7275 return -ENOMEM; 7276 7277 dev->rx_cpu_rmap_auto = true; 7278 return 0; 7279 } 7280 EXPORT_SYMBOL(netif_enable_cpu_rmap); 7281 7282 static void netif_del_cpu_rmap(struct net_device *dev) 7283 { 7284 struct cpu_rmap *rmap = dev->rx_cpu_rmap; 7285 7286 if (!dev->rx_cpu_rmap_auto) 7287 return; 7288 7289 /* Free the rmap */ 7290 cpu_rmap_put(rmap); 7291 dev->rx_cpu_rmap = NULL; 7292 dev->rx_cpu_rmap_auto = false; 7293 } 7294 7295 #else 7296 static void netif_napi_affinity_release(struct kref *ref) 7297 { 7298 } 7299 7300 int netif_enable_cpu_rmap(struct net_device *dev, unsigned int num_irqs) 7301 { 7302 return 0; 7303 } 7304 EXPORT_SYMBOL(netif_enable_cpu_rmap); 7305 7306 static void netif_del_cpu_rmap(struct net_device *dev) 7307 { 7308 } 7309 #endif 7310 7311 void netif_set_affinity_auto(struct net_device *dev) 7312 { 7313 unsigned int i, maxqs, numa; 7314 7315 maxqs = max(dev->num_tx_queues, dev->num_rx_queues); 7316 numa = dev_to_node(&dev->dev); 7317 7318 for (i = 0; i < maxqs; i++) 7319 cpumask_set_cpu(cpumask_local_spread(i, numa), 7320 &dev->napi_config[i].affinity_mask); 7321 7322 dev->irq_affinity_auto = true; 7323 } 7324 EXPORT_SYMBOL(netif_set_affinity_auto); 7325 7326 void netif_napi_set_irq_locked(struct napi_struct *napi, int irq) 7327 { 7328 int rc; 7329 7330 netdev_assert_locked_or_invisible(napi->dev); 7331 7332 if (napi->irq == irq) 7333 return; 7334 7335 /* Remove existing resources */ 7336 if (test_and_clear_bit(NAPI_STATE_HAS_NOTIFIER, &napi->state)) 7337 irq_set_affinity_notifier(napi->irq, NULL); 7338 7339 napi->irq = irq; 7340 if (irq < 0 || 7341 (!napi->dev->rx_cpu_rmap_auto && !napi->dev->irq_affinity_auto)) 7342 return; 7343 7344 /* Abort for buggy drivers */ 7345 if (napi->dev->irq_affinity_auto && WARN_ON_ONCE(!napi->config)) 7346 return; 7347 7348 #ifdef CONFIG_RFS_ACCEL 7349 if (napi->dev->rx_cpu_rmap_auto) { 7350 rc = cpu_rmap_add(napi->dev->rx_cpu_rmap, napi); 7351 if (rc < 0) 7352 return; 7353 7354 cpu_rmap_get(napi->dev->rx_cpu_rmap); 7355 napi->napi_rmap_idx = rc; 7356 } 7357 #endif 7358 7359 /* Use core IRQ notifier */ 7360 napi->notify.notify = netif_napi_irq_notify; 7361 napi->notify.release = netif_napi_affinity_release; 7362 rc = irq_set_affinity_notifier(irq, &napi->notify); 7363 if (rc) { 7364 netdev_warn(napi->dev, "Unable to set IRQ notifier (%d)\n", 7365 rc); 7366 goto put_rmap; 7367 } 7368 7369 set_bit(NAPI_STATE_HAS_NOTIFIER, &napi->state); 7370 return; 7371 7372 put_rmap: 7373 #ifdef CONFIG_RFS_ACCEL 7374 if (napi->dev->rx_cpu_rmap_auto) { 7375 napi->dev->rx_cpu_rmap->obj[napi->napi_rmap_idx] = NULL; 7376 cpu_rmap_put(napi->dev->rx_cpu_rmap); 7377 napi->napi_rmap_idx = -1; 7378 } 7379 #endif 7380 napi->notify.notify = NULL; 7381 napi->notify.release = NULL; 7382 } 7383 EXPORT_SYMBOL(netif_napi_set_irq_locked); 7384 7385 static void napi_restore_config(struct napi_struct *n) 7386 { 7387 n->defer_hard_irqs = n->config->defer_hard_irqs; 7388 n->gro_flush_timeout = n->config->gro_flush_timeout; 7389 n->irq_suspend_timeout = n->config->irq_suspend_timeout; 7390 7391 if (n->dev->irq_affinity_auto && 7392 test_bit(NAPI_STATE_HAS_NOTIFIER, &n->state)) 7393 irq_set_affinity(n->irq, &n->config->affinity_mask); 7394 7395 /* a NAPI ID might be stored in the config, if so use it. if not, use 7396 * napi_hash_add to generate one for us. 7397 */ 7398 if (n->config->napi_id) { 7399 napi_hash_add_with_id(n, n->config->napi_id); 7400 } else { 7401 napi_hash_add(n); 7402 n->config->napi_id = n->napi_id; 7403 } 7404 7405 WARN_ON_ONCE(napi_set_threaded(n, n->config->threaded)); 7406 } 7407 7408 static void napi_save_config(struct napi_struct *n) 7409 { 7410 n->config->defer_hard_irqs = n->defer_hard_irqs; 7411 n->config->gro_flush_timeout = n->gro_flush_timeout; 7412 n->config->irq_suspend_timeout = n->irq_suspend_timeout; 7413 napi_hash_del(n); 7414 } 7415 7416 /* Netlink wants the NAPI list to be sorted by ID, if adding a NAPI which will 7417 * inherit an existing ID try to insert it at the right position. 7418 */ 7419 static void 7420 netif_napi_dev_list_add(struct net_device *dev, struct napi_struct *napi) 7421 { 7422 unsigned int new_id, pos_id; 7423 struct list_head *higher; 7424 struct napi_struct *pos; 7425 7426 new_id = UINT_MAX; 7427 if (napi->config && napi->config->napi_id) 7428 new_id = napi->config->napi_id; 7429 7430 higher = &dev->napi_list; 7431 list_for_each_entry(pos, &dev->napi_list, dev_list) { 7432 if (napi_id_valid(pos->napi_id)) 7433 pos_id = pos->napi_id; 7434 else if (pos->config) 7435 pos_id = pos->config->napi_id; 7436 else 7437 pos_id = UINT_MAX; 7438 7439 if (pos_id <= new_id) 7440 break; 7441 higher = &pos->dev_list; 7442 } 7443 list_add_rcu(&napi->dev_list, higher); /* adds after higher */ 7444 } 7445 7446 /* Double check that napi_get_frags() allocates skbs with 7447 * skb->head being backed by slab, not a page fragment. 7448 * This is to make sure bug fixed in 3226b158e67c 7449 * ("net: avoid 32 x truesize under-estimation for tiny skbs") 7450 * does not accidentally come back. 7451 */ 7452 static void napi_get_frags_check(struct napi_struct *napi) 7453 { 7454 struct sk_buff *skb; 7455 7456 local_bh_disable(); 7457 skb = napi_get_frags(napi); 7458 WARN_ON_ONCE(skb && skb->head_frag); 7459 napi_free_frags(napi); 7460 local_bh_enable(); 7461 } 7462 7463 void netif_napi_add_weight_locked(struct net_device *dev, 7464 struct napi_struct *napi, 7465 int (*poll)(struct napi_struct *, int), 7466 int weight) 7467 { 7468 netdev_assert_locked(dev); 7469 if (WARN_ON(test_and_set_bit(NAPI_STATE_LISTED, &napi->state))) 7470 return; 7471 7472 INIT_LIST_HEAD(&napi->poll_list); 7473 INIT_HLIST_NODE(&napi->napi_hash_node); 7474 hrtimer_setup(&napi->timer, napi_watchdog, CLOCK_MONOTONIC, HRTIMER_MODE_REL_PINNED); 7475 gro_init(&napi->gro); 7476 napi->skb = NULL; 7477 napi->poll = poll; 7478 if (weight > NAPI_POLL_WEIGHT) 7479 netdev_err_once(dev, "%s() called with weight %d\n", __func__, 7480 weight); 7481 napi->weight = weight; 7482 napi->dev = dev; 7483 #ifdef CONFIG_NETPOLL 7484 napi->poll_owner = -1; 7485 #endif 7486 napi->list_owner = -1; 7487 set_bit(NAPI_STATE_SCHED, &napi->state); 7488 set_bit(NAPI_STATE_NPSVC, &napi->state); 7489 netif_napi_dev_list_add(dev, napi); 7490 7491 /* default settings from sysfs are applied to all NAPIs. any per-NAPI 7492 * configuration will be loaded in napi_enable 7493 */ 7494 napi_set_defer_hard_irqs(napi, READ_ONCE(dev->napi_defer_hard_irqs)); 7495 napi_set_gro_flush_timeout(napi, READ_ONCE(dev->gro_flush_timeout)); 7496 7497 napi_get_frags_check(napi); 7498 /* Create kthread for this napi if dev->threaded is set. 7499 * Clear dev->threaded if kthread creation failed so that 7500 * threaded mode will not be enabled in napi_enable(). 7501 */ 7502 if (napi_get_threaded_config(dev, napi)) 7503 if (napi_kthread_create(napi)) 7504 dev->threaded = NETDEV_NAPI_THREADED_DISABLED; 7505 netif_napi_set_irq_locked(napi, -1); 7506 } 7507 EXPORT_SYMBOL(netif_napi_add_weight_locked); 7508 7509 void napi_disable_locked(struct napi_struct *n) 7510 { 7511 unsigned long val, new; 7512 7513 might_sleep(); 7514 netdev_assert_locked(n->dev); 7515 7516 set_bit(NAPI_STATE_DISABLE, &n->state); 7517 7518 val = READ_ONCE(n->state); 7519 do { 7520 while (val & (NAPIF_STATE_SCHED | NAPIF_STATE_NPSVC)) { 7521 usleep_range(20, 200); 7522 val = READ_ONCE(n->state); 7523 } 7524 7525 new = val | NAPIF_STATE_SCHED | NAPIF_STATE_NPSVC; 7526 new &= ~(NAPIF_STATE_THREADED | NAPIF_STATE_PREFER_BUSY_POLL); 7527 } while (!try_cmpxchg(&n->state, &val, new)); 7528 7529 hrtimer_cancel(&n->timer); 7530 7531 if (n->config) 7532 napi_save_config(n); 7533 else 7534 napi_hash_del(n); 7535 7536 clear_bit(NAPI_STATE_DISABLE, &n->state); 7537 } 7538 EXPORT_SYMBOL(napi_disable_locked); 7539 7540 /** 7541 * napi_disable() - prevent NAPI from scheduling 7542 * @n: NAPI context 7543 * 7544 * Stop NAPI from being scheduled on this context. 7545 * Waits till any outstanding processing completes. 7546 * Takes netdev_lock() for associated net_device. 7547 */ 7548 void napi_disable(struct napi_struct *n) 7549 { 7550 netdev_lock(n->dev); 7551 napi_disable_locked(n); 7552 netdev_unlock(n->dev); 7553 } 7554 EXPORT_SYMBOL(napi_disable); 7555 7556 void napi_enable_locked(struct napi_struct *n) 7557 { 7558 unsigned long new, val = READ_ONCE(n->state); 7559 7560 if (n->config) 7561 napi_restore_config(n); 7562 else 7563 napi_hash_add(n); 7564 7565 do { 7566 BUG_ON(!test_bit(NAPI_STATE_SCHED, &val)); 7567 7568 new = val & ~(NAPIF_STATE_SCHED | NAPIF_STATE_NPSVC); 7569 if (n->dev->threaded && n->thread) 7570 new |= NAPIF_STATE_THREADED; 7571 } while (!try_cmpxchg(&n->state, &val, new)); 7572 } 7573 EXPORT_SYMBOL(napi_enable_locked); 7574 7575 /** 7576 * napi_enable() - enable NAPI scheduling 7577 * @n: NAPI context 7578 * 7579 * Enable scheduling of a NAPI instance. 7580 * Must be paired with napi_disable(). 7581 * Takes netdev_lock() for associated net_device. 7582 */ 7583 void napi_enable(struct napi_struct *n) 7584 { 7585 netdev_lock(n->dev); 7586 napi_enable_locked(n); 7587 netdev_unlock(n->dev); 7588 } 7589 EXPORT_SYMBOL(napi_enable); 7590 7591 /* Must be called in process context */ 7592 void __netif_napi_del_locked(struct napi_struct *napi) 7593 { 7594 netdev_assert_locked(napi->dev); 7595 7596 if (!test_and_clear_bit(NAPI_STATE_LISTED, &napi->state)) 7597 return; 7598 7599 /* Make sure NAPI is disabled (or was never enabled). */ 7600 WARN_ON(!test_bit(NAPI_STATE_SCHED, &napi->state)); 7601 7602 if (test_and_clear_bit(NAPI_STATE_HAS_NOTIFIER, &napi->state)) 7603 irq_set_affinity_notifier(napi->irq, NULL); 7604 7605 if (napi->config) { 7606 napi->index = -1; 7607 napi->config = NULL; 7608 } 7609 7610 list_del_rcu(&napi->dev_list); 7611 napi_free_frags(napi); 7612 7613 gro_cleanup(&napi->gro); 7614 7615 if (napi->thread) { 7616 kthread_stop(napi->thread); 7617 napi->thread = NULL; 7618 } 7619 } 7620 EXPORT_SYMBOL(__netif_napi_del_locked); 7621 7622 static int __napi_poll(struct napi_struct *n, bool *repoll) 7623 { 7624 int work, weight; 7625 7626 weight = n->weight; 7627 7628 /* This NAPI_STATE_SCHED test is for avoiding a race 7629 * with netpoll's poll_napi(). Only the entity which 7630 * obtains the lock and sees NAPI_STATE_SCHED set will 7631 * actually make the ->poll() call. Therefore we avoid 7632 * accidentally calling ->poll() when NAPI is not scheduled. 7633 */ 7634 work = 0; 7635 if (napi_is_scheduled(n)) { 7636 work = n->poll(n, weight); 7637 trace_napi_poll(n, work, weight); 7638 7639 xdp_do_check_flushed(n); 7640 } 7641 7642 if (unlikely(work > weight)) 7643 netdev_err_once(n->dev, "NAPI poll function %pS returned %d, exceeding its budget of %d.\n", 7644 n->poll, work, weight); 7645 7646 if (likely(work < weight)) 7647 return work; 7648 7649 /* Drivers must not modify the NAPI state if they 7650 * consume the entire weight. In such cases this code 7651 * still "owns" the NAPI instance and therefore can 7652 * move the instance around on the list at-will. 7653 */ 7654 if (unlikely(napi_disable_pending(n))) { 7655 napi_complete(n); 7656 return work; 7657 } 7658 7659 /* The NAPI context has more processing work, but busy-polling 7660 * is preferred. Exit early. 7661 */ 7662 if (napi_prefer_busy_poll(n)) { 7663 if (napi_complete_done(n, work)) { 7664 /* If timeout is not set, we need to make sure 7665 * that the NAPI is re-scheduled. 7666 */ 7667 napi_schedule(n); 7668 } 7669 return work; 7670 } 7671 7672 /* Flush too old packets. If HZ < 1000, flush all packets */ 7673 gro_flush_normal(&n->gro, HZ >= 1000); 7674 7675 /* Some drivers may have called napi_schedule 7676 * prior to exhausting their budget. 7677 */ 7678 if (unlikely(!list_empty(&n->poll_list))) { 7679 pr_warn_once("%s: Budget exhausted after napi rescheduled\n", 7680 n->dev ? n->dev->name : "backlog"); 7681 return work; 7682 } 7683 7684 *repoll = true; 7685 7686 return work; 7687 } 7688 7689 static int napi_poll(struct napi_struct *n, struct list_head *repoll) 7690 { 7691 bool do_repoll = false; 7692 void *have; 7693 int work; 7694 7695 list_del_init(&n->poll_list); 7696 7697 have = netpoll_poll_lock(n); 7698 7699 work = __napi_poll(n, &do_repoll); 7700 7701 if (do_repoll) { 7702 #if defined(CONFIG_DEBUG_NET) 7703 if (unlikely(!napi_is_scheduled(n))) 7704 pr_crit("repoll requested for device %s %ps but napi is not scheduled.\n", 7705 n->dev->name, n->poll); 7706 #endif 7707 list_add_tail(&n->poll_list, repoll); 7708 } 7709 netpoll_poll_unlock(have); 7710 7711 return work; 7712 } 7713 7714 static int napi_thread_wait(struct napi_struct *napi) 7715 { 7716 set_current_state(TASK_INTERRUPTIBLE); 7717 7718 while (!kthread_should_stop()) { 7719 /* Testing SCHED_THREADED bit here to make sure the current 7720 * kthread owns this napi and could poll on this napi. 7721 * Testing SCHED bit is not enough because SCHED bit might be 7722 * set by some other busy poll thread or by napi_disable(). 7723 */ 7724 if (test_bit(NAPI_STATE_SCHED_THREADED, &napi->state)) { 7725 WARN_ON(!list_empty(&napi->poll_list)); 7726 __set_current_state(TASK_RUNNING); 7727 return 0; 7728 } 7729 7730 schedule(); 7731 set_current_state(TASK_INTERRUPTIBLE); 7732 } 7733 __set_current_state(TASK_RUNNING); 7734 7735 return -1; 7736 } 7737 7738 static void napi_threaded_poll_loop(struct napi_struct *napi) 7739 { 7740 struct bpf_net_context __bpf_net_ctx, *bpf_net_ctx; 7741 struct softnet_data *sd; 7742 unsigned long last_qs = jiffies; 7743 7744 for (;;) { 7745 bool repoll = false; 7746 void *have; 7747 7748 local_bh_disable(); 7749 bpf_net_ctx = bpf_net_ctx_set(&__bpf_net_ctx); 7750 7751 sd = this_cpu_ptr(&softnet_data); 7752 sd->in_napi_threaded_poll = true; 7753 7754 have = netpoll_poll_lock(napi); 7755 __napi_poll(napi, &repoll); 7756 netpoll_poll_unlock(have); 7757 7758 sd->in_napi_threaded_poll = false; 7759 barrier(); 7760 7761 if (sd_has_rps_ipi_waiting(sd)) { 7762 local_irq_disable(); 7763 net_rps_action_and_irq_enable(sd); 7764 } 7765 skb_defer_free_flush(); 7766 bpf_net_ctx_clear(bpf_net_ctx); 7767 local_bh_enable(); 7768 7769 if (!repoll) 7770 break; 7771 7772 rcu_softirq_qs_periodic(last_qs); 7773 cond_resched(); 7774 } 7775 } 7776 7777 static int napi_threaded_poll(void *data) 7778 { 7779 struct napi_struct *napi = data; 7780 7781 while (!napi_thread_wait(napi)) 7782 napi_threaded_poll_loop(napi); 7783 7784 return 0; 7785 } 7786 7787 static __latent_entropy void net_rx_action(void) 7788 { 7789 struct softnet_data *sd = this_cpu_ptr(&softnet_data); 7790 unsigned long time_limit = jiffies + 7791 usecs_to_jiffies(READ_ONCE(net_hotdata.netdev_budget_usecs)); 7792 struct bpf_net_context __bpf_net_ctx, *bpf_net_ctx; 7793 int budget = READ_ONCE(net_hotdata.netdev_budget); 7794 LIST_HEAD(list); 7795 LIST_HEAD(repoll); 7796 7797 bpf_net_ctx = bpf_net_ctx_set(&__bpf_net_ctx); 7798 start: 7799 sd->in_net_rx_action = true; 7800 local_irq_disable(); 7801 list_splice_init(&sd->poll_list, &list); 7802 local_irq_enable(); 7803 7804 for (;;) { 7805 struct napi_struct *n; 7806 7807 skb_defer_free_flush(); 7808 7809 if (list_empty(&list)) { 7810 if (list_empty(&repoll)) { 7811 sd->in_net_rx_action = false; 7812 barrier(); 7813 /* We need to check if ____napi_schedule() 7814 * had refilled poll_list while 7815 * sd->in_net_rx_action was true. 7816 */ 7817 if (!list_empty(&sd->poll_list)) 7818 goto start; 7819 if (!sd_has_rps_ipi_waiting(sd)) 7820 goto end; 7821 } 7822 break; 7823 } 7824 7825 n = list_first_entry(&list, struct napi_struct, poll_list); 7826 budget -= napi_poll(n, &repoll); 7827 7828 /* If softirq window is exhausted then punt. 7829 * Allow this to run for 2 jiffies since which will allow 7830 * an average latency of 1.5/HZ. 7831 */ 7832 if (unlikely(budget <= 0 || 7833 time_after_eq(jiffies, time_limit))) { 7834 /* Pairs with READ_ONCE() in softnet_seq_show() */ 7835 WRITE_ONCE(sd->time_squeeze, sd->time_squeeze + 1); 7836 break; 7837 } 7838 } 7839 7840 local_irq_disable(); 7841 7842 list_splice_tail_init(&sd->poll_list, &list); 7843 list_splice_tail(&repoll, &list); 7844 list_splice(&list, &sd->poll_list); 7845 if (!list_empty(&sd->poll_list)) 7846 __raise_softirq_irqoff(NET_RX_SOFTIRQ); 7847 else 7848 sd->in_net_rx_action = false; 7849 7850 net_rps_action_and_irq_enable(sd); 7851 end: 7852 bpf_net_ctx_clear(bpf_net_ctx); 7853 } 7854 7855 struct netdev_adjacent { 7856 struct net_device *dev; 7857 netdevice_tracker dev_tracker; 7858 7859 /* upper master flag, there can only be one master device per list */ 7860 bool master; 7861 7862 /* lookup ignore flag */ 7863 bool ignore; 7864 7865 /* counter for the number of times this device was added to us */ 7866 u16 ref_nr; 7867 7868 /* private field for the users */ 7869 void *private; 7870 7871 struct list_head list; 7872 struct rcu_head rcu; 7873 }; 7874 7875 static struct netdev_adjacent *__netdev_find_adj(struct net_device *adj_dev, 7876 struct list_head *adj_list) 7877 { 7878 struct netdev_adjacent *adj; 7879 7880 list_for_each_entry(adj, adj_list, list) { 7881 if (adj->dev == adj_dev) 7882 return adj; 7883 } 7884 return NULL; 7885 } 7886 7887 static int ____netdev_has_upper_dev(struct net_device *upper_dev, 7888 struct netdev_nested_priv *priv) 7889 { 7890 struct net_device *dev = (struct net_device *)priv->data; 7891 7892 return upper_dev == dev; 7893 } 7894 7895 /** 7896 * netdev_has_upper_dev - Check if device is linked to an upper device 7897 * @dev: device 7898 * @upper_dev: upper device to check 7899 * 7900 * Find out if a device is linked to specified upper device and return true 7901 * in case it is. Note that this checks only immediate upper device, 7902 * not through a complete stack of devices. The caller must hold the RTNL lock. 7903 */ 7904 bool netdev_has_upper_dev(struct net_device *dev, 7905 struct net_device *upper_dev) 7906 { 7907 struct netdev_nested_priv priv = { 7908 .data = (void *)upper_dev, 7909 }; 7910 7911 ASSERT_RTNL(); 7912 7913 return netdev_walk_all_upper_dev_rcu(dev, ____netdev_has_upper_dev, 7914 &priv); 7915 } 7916 EXPORT_SYMBOL(netdev_has_upper_dev); 7917 7918 /** 7919 * netdev_has_upper_dev_all_rcu - Check if device is linked to an upper device 7920 * @dev: device 7921 * @upper_dev: upper device to check 7922 * 7923 * Find out if a device is linked to specified upper device and return true 7924 * in case it is. Note that this checks the entire upper device chain. 7925 * The caller must hold rcu lock. 7926 */ 7927 7928 bool netdev_has_upper_dev_all_rcu(struct net_device *dev, 7929 struct net_device *upper_dev) 7930 { 7931 struct netdev_nested_priv priv = { 7932 .data = (void *)upper_dev, 7933 }; 7934 7935 return !!netdev_walk_all_upper_dev_rcu(dev, ____netdev_has_upper_dev, 7936 &priv); 7937 } 7938 EXPORT_SYMBOL(netdev_has_upper_dev_all_rcu); 7939 7940 /** 7941 * netdev_has_any_upper_dev - Check if device is linked to some device 7942 * @dev: device 7943 * 7944 * Find out if a device is linked to an upper device and return true in case 7945 * it is. The caller must hold the RTNL lock. 7946 */ 7947 bool netdev_has_any_upper_dev(struct net_device *dev) 7948 { 7949 ASSERT_RTNL(); 7950 7951 return !list_empty(&dev->adj_list.upper); 7952 } 7953 EXPORT_SYMBOL(netdev_has_any_upper_dev); 7954 7955 /** 7956 * netdev_master_upper_dev_get - Get master upper device 7957 * @dev: device 7958 * 7959 * Find a master upper device and return pointer to it or NULL in case 7960 * it's not there. The caller must hold the RTNL lock. 7961 */ 7962 struct net_device *netdev_master_upper_dev_get(struct net_device *dev) 7963 { 7964 struct netdev_adjacent *upper; 7965 7966 ASSERT_RTNL(); 7967 7968 if (list_empty(&dev->adj_list.upper)) 7969 return NULL; 7970 7971 upper = list_first_entry(&dev->adj_list.upper, 7972 struct netdev_adjacent, list); 7973 if (likely(upper->master)) 7974 return upper->dev; 7975 return NULL; 7976 } 7977 EXPORT_SYMBOL(netdev_master_upper_dev_get); 7978 7979 static struct net_device *__netdev_master_upper_dev_get(struct net_device *dev) 7980 { 7981 struct netdev_adjacent *upper; 7982 7983 ASSERT_RTNL(); 7984 7985 if (list_empty(&dev->adj_list.upper)) 7986 return NULL; 7987 7988 upper = list_first_entry(&dev->adj_list.upper, 7989 struct netdev_adjacent, list); 7990 if (likely(upper->master) && !upper->ignore) 7991 return upper->dev; 7992 return NULL; 7993 } 7994 7995 /** 7996 * netdev_has_any_lower_dev - Check if device is linked to some device 7997 * @dev: device 7998 * 7999 * Find out if a device is linked to a lower device and return true in case 8000 * it is. The caller must hold the RTNL lock. 8001 */ 8002 static bool netdev_has_any_lower_dev(struct net_device *dev) 8003 { 8004 ASSERT_RTNL(); 8005 8006 return !list_empty(&dev->adj_list.lower); 8007 } 8008 8009 void *netdev_adjacent_get_private(struct list_head *adj_list) 8010 { 8011 struct netdev_adjacent *adj; 8012 8013 adj = list_entry(adj_list, struct netdev_adjacent, list); 8014 8015 return adj->private; 8016 } 8017 EXPORT_SYMBOL(netdev_adjacent_get_private); 8018 8019 /** 8020 * netdev_upper_get_next_dev_rcu - Get the next dev from upper list 8021 * @dev: device 8022 * @iter: list_head ** of the current position 8023 * 8024 * Gets the next device from the dev's upper list, starting from iter 8025 * position. The caller must hold RCU read lock. 8026 */ 8027 struct net_device *netdev_upper_get_next_dev_rcu(struct net_device *dev, 8028 struct list_head **iter) 8029 { 8030 struct netdev_adjacent *upper; 8031 8032 WARN_ON_ONCE(!rcu_read_lock_held() && !lockdep_rtnl_is_held()); 8033 8034 upper = list_entry_rcu((*iter)->next, struct netdev_adjacent, list); 8035 8036 if (&upper->list == &dev->adj_list.upper) 8037 return NULL; 8038 8039 *iter = &upper->list; 8040 8041 return upper->dev; 8042 } 8043 EXPORT_SYMBOL(netdev_upper_get_next_dev_rcu); 8044 8045 static struct net_device *__netdev_next_upper_dev(struct net_device *dev, 8046 struct list_head **iter, 8047 bool *ignore) 8048 { 8049 struct netdev_adjacent *upper; 8050 8051 upper = list_entry((*iter)->next, struct netdev_adjacent, list); 8052 8053 if (&upper->list == &dev->adj_list.upper) 8054 return NULL; 8055 8056 *iter = &upper->list; 8057 *ignore = upper->ignore; 8058 8059 return upper->dev; 8060 } 8061 8062 static struct net_device *netdev_next_upper_dev_rcu(struct net_device *dev, 8063 struct list_head **iter) 8064 { 8065 struct netdev_adjacent *upper; 8066 8067 WARN_ON_ONCE(!rcu_read_lock_held() && !lockdep_rtnl_is_held()); 8068 8069 upper = list_entry_rcu((*iter)->next, struct netdev_adjacent, list); 8070 8071 if (&upper->list == &dev->adj_list.upper) 8072 return NULL; 8073 8074 *iter = &upper->list; 8075 8076 return upper->dev; 8077 } 8078 8079 static int __netdev_walk_all_upper_dev(struct net_device *dev, 8080 int (*fn)(struct net_device *dev, 8081 struct netdev_nested_priv *priv), 8082 struct netdev_nested_priv *priv) 8083 { 8084 struct net_device *udev, *next, *now, *dev_stack[MAX_NEST_DEV + 1]; 8085 struct list_head *niter, *iter, *iter_stack[MAX_NEST_DEV + 1]; 8086 int ret, cur = 0; 8087 bool ignore; 8088 8089 now = dev; 8090 iter = &dev->adj_list.upper; 8091 8092 while (1) { 8093 if (now != dev) { 8094 ret = fn(now, priv); 8095 if (ret) 8096 return ret; 8097 } 8098 8099 next = NULL; 8100 while (1) { 8101 udev = __netdev_next_upper_dev(now, &iter, &ignore); 8102 if (!udev) 8103 break; 8104 if (ignore) 8105 continue; 8106 8107 next = udev; 8108 niter = &udev->adj_list.upper; 8109 dev_stack[cur] = now; 8110 iter_stack[cur++] = iter; 8111 break; 8112 } 8113 8114 if (!next) { 8115 if (!cur) 8116 return 0; 8117 next = dev_stack[--cur]; 8118 niter = iter_stack[cur]; 8119 } 8120 8121 now = next; 8122 iter = niter; 8123 } 8124 8125 return 0; 8126 } 8127 8128 int netdev_walk_all_upper_dev_rcu(struct net_device *dev, 8129 int (*fn)(struct net_device *dev, 8130 struct netdev_nested_priv *priv), 8131 struct netdev_nested_priv *priv) 8132 { 8133 struct net_device *udev, *next, *now, *dev_stack[MAX_NEST_DEV + 1]; 8134 struct list_head *niter, *iter, *iter_stack[MAX_NEST_DEV + 1]; 8135 int ret, cur = 0; 8136 8137 now = dev; 8138 iter = &dev->adj_list.upper; 8139 8140 while (1) { 8141 if (now != dev) { 8142 ret = fn(now, priv); 8143 if (ret) 8144 return ret; 8145 } 8146 8147 next = NULL; 8148 while (1) { 8149 udev = netdev_next_upper_dev_rcu(now, &iter); 8150 if (!udev) 8151 break; 8152 8153 next = udev; 8154 niter = &udev->adj_list.upper; 8155 dev_stack[cur] = now; 8156 iter_stack[cur++] = iter; 8157 break; 8158 } 8159 8160 if (!next) { 8161 if (!cur) 8162 return 0; 8163 next = dev_stack[--cur]; 8164 niter = iter_stack[cur]; 8165 } 8166 8167 now = next; 8168 iter = niter; 8169 } 8170 8171 return 0; 8172 } 8173 EXPORT_SYMBOL_GPL(netdev_walk_all_upper_dev_rcu); 8174 8175 static bool __netdev_has_upper_dev(struct net_device *dev, 8176 struct net_device *upper_dev) 8177 { 8178 struct netdev_nested_priv priv = { 8179 .flags = 0, 8180 .data = (void *)upper_dev, 8181 }; 8182 8183 ASSERT_RTNL(); 8184 8185 return __netdev_walk_all_upper_dev(dev, ____netdev_has_upper_dev, 8186 &priv); 8187 } 8188 8189 /** 8190 * netdev_lower_get_next_private - Get the next ->private from the 8191 * lower neighbour list 8192 * @dev: device 8193 * @iter: list_head ** of the current position 8194 * 8195 * Gets the next netdev_adjacent->private from the dev's lower neighbour 8196 * list, starting from iter position. The caller must hold either hold the 8197 * RTNL lock or its own locking that guarantees that the neighbour lower 8198 * list will remain unchanged. 8199 */ 8200 void *netdev_lower_get_next_private(struct net_device *dev, 8201 struct list_head **iter) 8202 { 8203 struct netdev_adjacent *lower; 8204 8205 lower = list_entry(*iter, struct netdev_adjacent, list); 8206 8207 if (&lower->list == &dev->adj_list.lower) 8208 return NULL; 8209 8210 *iter = lower->list.next; 8211 8212 return lower->private; 8213 } 8214 EXPORT_SYMBOL(netdev_lower_get_next_private); 8215 8216 /** 8217 * netdev_lower_get_next_private_rcu - Get the next ->private from the 8218 * lower neighbour list, RCU 8219 * variant 8220 * @dev: device 8221 * @iter: list_head ** of the current position 8222 * 8223 * Gets the next netdev_adjacent->private from the dev's lower neighbour 8224 * list, starting from iter position. The caller must hold RCU read lock. 8225 */ 8226 void *netdev_lower_get_next_private_rcu(struct net_device *dev, 8227 struct list_head **iter) 8228 { 8229 struct netdev_adjacent *lower; 8230 8231 WARN_ON_ONCE(!rcu_read_lock_held() && !rcu_read_lock_bh_held()); 8232 8233 lower = list_entry_rcu((*iter)->next, struct netdev_adjacent, list); 8234 8235 if (&lower->list == &dev->adj_list.lower) 8236 return NULL; 8237 8238 *iter = &lower->list; 8239 8240 return lower->private; 8241 } 8242 EXPORT_SYMBOL(netdev_lower_get_next_private_rcu); 8243 8244 /** 8245 * netdev_lower_get_next - Get the next device from the lower neighbour 8246 * list 8247 * @dev: device 8248 * @iter: list_head ** of the current position 8249 * 8250 * Gets the next netdev_adjacent from the dev's lower neighbour 8251 * list, starting from iter position. The caller must hold RTNL lock or 8252 * its own locking that guarantees that the neighbour lower 8253 * list will remain unchanged. 8254 */ 8255 void *netdev_lower_get_next(struct net_device *dev, struct list_head **iter) 8256 { 8257 struct netdev_adjacent *lower; 8258 8259 lower = list_entry(*iter, struct netdev_adjacent, list); 8260 8261 if (&lower->list == &dev->adj_list.lower) 8262 return NULL; 8263 8264 *iter = lower->list.next; 8265 8266 return lower->dev; 8267 } 8268 EXPORT_SYMBOL(netdev_lower_get_next); 8269 8270 static struct net_device *netdev_next_lower_dev(struct net_device *dev, 8271 struct list_head **iter) 8272 { 8273 struct netdev_adjacent *lower; 8274 8275 lower = list_entry((*iter)->next, struct netdev_adjacent, list); 8276 8277 if (&lower->list == &dev->adj_list.lower) 8278 return NULL; 8279 8280 *iter = &lower->list; 8281 8282 return lower->dev; 8283 } 8284 8285 static struct net_device *__netdev_next_lower_dev(struct net_device *dev, 8286 struct list_head **iter, 8287 bool *ignore) 8288 { 8289 struct netdev_adjacent *lower; 8290 8291 lower = list_entry((*iter)->next, struct netdev_adjacent, list); 8292 8293 if (&lower->list == &dev->adj_list.lower) 8294 return NULL; 8295 8296 *iter = &lower->list; 8297 *ignore = lower->ignore; 8298 8299 return lower->dev; 8300 } 8301 8302 int netdev_walk_all_lower_dev(struct net_device *dev, 8303 int (*fn)(struct net_device *dev, 8304 struct netdev_nested_priv *priv), 8305 struct netdev_nested_priv *priv) 8306 { 8307 struct net_device *ldev, *next, *now, *dev_stack[MAX_NEST_DEV + 1]; 8308 struct list_head *niter, *iter, *iter_stack[MAX_NEST_DEV + 1]; 8309 int ret, cur = 0; 8310 8311 now = dev; 8312 iter = &dev->adj_list.lower; 8313 8314 while (1) { 8315 if (now != dev) { 8316 ret = fn(now, priv); 8317 if (ret) 8318 return ret; 8319 } 8320 8321 next = NULL; 8322 while (1) { 8323 ldev = netdev_next_lower_dev(now, &iter); 8324 if (!ldev) 8325 break; 8326 8327 next = ldev; 8328 niter = &ldev->adj_list.lower; 8329 dev_stack[cur] = now; 8330 iter_stack[cur++] = iter; 8331 break; 8332 } 8333 8334 if (!next) { 8335 if (!cur) 8336 return 0; 8337 next = dev_stack[--cur]; 8338 niter = iter_stack[cur]; 8339 } 8340 8341 now = next; 8342 iter = niter; 8343 } 8344 8345 return 0; 8346 } 8347 EXPORT_SYMBOL_GPL(netdev_walk_all_lower_dev); 8348 8349 static int __netdev_walk_all_lower_dev(struct net_device *dev, 8350 int (*fn)(struct net_device *dev, 8351 struct netdev_nested_priv *priv), 8352 struct netdev_nested_priv *priv) 8353 { 8354 struct net_device *ldev, *next, *now, *dev_stack[MAX_NEST_DEV + 1]; 8355 struct list_head *niter, *iter, *iter_stack[MAX_NEST_DEV + 1]; 8356 int ret, cur = 0; 8357 bool ignore; 8358 8359 now = dev; 8360 iter = &dev->adj_list.lower; 8361 8362 while (1) { 8363 if (now != dev) { 8364 ret = fn(now, priv); 8365 if (ret) 8366 return ret; 8367 } 8368 8369 next = NULL; 8370 while (1) { 8371 ldev = __netdev_next_lower_dev(now, &iter, &ignore); 8372 if (!ldev) 8373 break; 8374 if (ignore) 8375 continue; 8376 8377 next = ldev; 8378 niter = &ldev->adj_list.lower; 8379 dev_stack[cur] = now; 8380 iter_stack[cur++] = iter; 8381 break; 8382 } 8383 8384 if (!next) { 8385 if (!cur) 8386 return 0; 8387 next = dev_stack[--cur]; 8388 niter = iter_stack[cur]; 8389 } 8390 8391 now = next; 8392 iter = niter; 8393 } 8394 8395 return 0; 8396 } 8397 8398 struct net_device *netdev_next_lower_dev_rcu(struct net_device *dev, 8399 struct list_head **iter) 8400 { 8401 struct netdev_adjacent *lower; 8402 8403 lower = list_entry_rcu((*iter)->next, struct netdev_adjacent, list); 8404 if (&lower->list == &dev->adj_list.lower) 8405 return NULL; 8406 8407 *iter = &lower->list; 8408 8409 return lower->dev; 8410 } 8411 EXPORT_SYMBOL(netdev_next_lower_dev_rcu); 8412 8413 static u8 __netdev_upper_depth(struct net_device *dev) 8414 { 8415 struct net_device *udev; 8416 struct list_head *iter; 8417 u8 max_depth = 0; 8418 bool ignore; 8419 8420 for (iter = &dev->adj_list.upper, 8421 udev = __netdev_next_upper_dev(dev, &iter, &ignore); 8422 udev; 8423 udev = __netdev_next_upper_dev(dev, &iter, &ignore)) { 8424 if (ignore) 8425 continue; 8426 if (max_depth < udev->upper_level) 8427 max_depth = udev->upper_level; 8428 } 8429 8430 return max_depth; 8431 } 8432 8433 static u8 __netdev_lower_depth(struct net_device *dev) 8434 { 8435 struct net_device *ldev; 8436 struct list_head *iter; 8437 u8 max_depth = 0; 8438 bool ignore; 8439 8440 for (iter = &dev->adj_list.lower, 8441 ldev = __netdev_next_lower_dev(dev, &iter, &ignore); 8442 ldev; 8443 ldev = __netdev_next_lower_dev(dev, &iter, &ignore)) { 8444 if (ignore) 8445 continue; 8446 if (max_depth < ldev->lower_level) 8447 max_depth = ldev->lower_level; 8448 } 8449 8450 return max_depth; 8451 } 8452 8453 static int __netdev_update_upper_level(struct net_device *dev, 8454 struct netdev_nested_priv *__unused) 8455 { 8456 dev->upper_level = __netdev_upper_depth(dev) + 1; 8457 return 0; 8458 } 8459 8460 #ifdef CONFIG_LOCKDEP 8461 static LIST_HEAD(net_unlink_list); 8462 8463 static void net_unlink_todo(struct net_device *dev) 8464 { 8465 if (list_empty(&dev->unlink_list)) 8466 list_add_tail(&dev->unlink_list, &net_unlink_list); 8467 } 8468 #endif 8469 8470 static int __netdev_update_lower_level(struct net_device *dev, 8471 struct netdev_nested_priv *priv) 8472 { 8473 dev->lower_level = __netdev_lower_depth(dev) + 1; 8474 8475 #ifdef CONFIG_LOCKDEP 8476 if (!priv) 8477 return 0; 8478 8479 if (priv->flags & NESTED_SYNC_IMM) 8480 dev->nested_level = dev->lower_level - 1; 8481 if (priv->flags & NESTED_SYNC_TODO) 8482 net_unlink_todo(dev); 8483 #endif 8484 return 0; 8485 } 8486 8487 int netdev_walk_all_lower_dev_rcu(struct net_device *dev, 8488 int (*fn)(struct net_device *dev, 8489 struct netdev_nested_priv *priv), 8490 struct netdev_nested_priv *priv) 8491 { 8492 struct net_device *ldev, *next, *now, *dev_stack[MAX_NEST_DEV + 1]; 8493 struct list_head *niter, *iter, *iter_stack[MAX_NEST_DEV + 1]; 8494 int ret, cur = 0; 8495 8496 now = dev; 8497 iter = &dev->adj_list.lower; 8498 8499 while (1) { 8500 if (now != dev) { 8501 ret = fn(now, priv); 8502 if (ret) 8503 return ret; 8504 } 8505 8506 next = NULL; 8507 while (1) { 8508 ldev = netdev_next_lower_dev_rcu(now, &iter); 8509 if (!ldev) 8510 break; 8511 8512 next = ldev; 8513 niter = &ldev->adj_list.lower; 8514 dev_stack[cur] = now; 8515 iter_stack[cur++] = iter; 8516 break; 8517 } 8518 8519 if (!next) { 8520 if (!cur) 8521 return 0; 8522 next = dev_stack[--cur]; 8523 niter = iter_stack[cur]; 8524 } 8525 8526 now = next; 8527 iter = niter; 8528 } 8529 8530 return 0; 8531 } 8532 EXPORT_SYMBOL_GPL(netdev_walk_all_lower_dev_rcu); 8533 8534 /** 8535 * netdev_lower_get_first_private_rcu - Get the first ->private from the 8536 * lower neighbour list, RCU 8537 * variant 8538 * @dev: device 8539 * 8540 * Gets the first netdev_adjacent->private from the dev's lower neighbour 8541 * list. The caller must hold RCU read lock. 8542 */ 8543 void *netdev_lower_get_first_private_rcu(struct net_device *dev) 8544 { 8545 struct netdev_adjacent *lower; 8546 8547 lower = list_first_or_null_rcu(&dev->adj_list.lower, 8548 struct netdev_adjacent, list); 8549 if (lower) 8550 return lower->private; 8551 return NULL; 8552 } 8553 EXPORT_SYMBOL(netdev_lower_get_first_private_rcu); 8554 8555 /** 8556 * netdev_master_upper_dev_get_rcu - Get master upper device 8557 * @dev: device 8558 * 8559 * Find a master upper device and return pointer to it or NULL in case 8560 * it's not there. The caller must hold the RCU read lock. 8561 */ 8562 struct net_device *netdev_master_upper_dev_get_rcu(struct net_device *dev) 8563 { 8564 struct netdev_adjacent *upper; 8565 8566 upper = list_first_or_null_rcu(&dev->adj_list.upper, 8567 struct netdev_adjacent, list); 8568 if (upper && likely(upper->master)) 8569 return upper->dev; 8570 return NULL; 8571 } 8572 EXPORT_SYMBOL(netdev_master_upper_dev_get_rcu); 8573 8574 static int netdev_adjacent_sysfs_add(struct net_device *dev, 8575 struct net_device *adj_dev, 8576 struct list_head *dev_list) 8577 { 8578 char linkname[IFNAMSIZ+7]; 8579 8580 sprintf(linkname, dev_list == &dev->adj_list.upper ? 8581 "upper_%s" : "lower_%s", adj_dev->name); 8582 return sysfs_create_link(&(dev->dev.kobj), &(adj_dev->dev.kobj), 8583 linkname); 8584 } 8585 static void netdev_adjacent_sysfs_del(struct net_device *dev, 8586 char *name, 8587 struct list_head *dev_list) 8588 { 8589 char linkname[IFNAMSIZ+7]; 8590 8591 sprintf(linkname, dev_list == &dev->adj_list.upper ? 8592 "upper_%s" : "lower_%s", name); 8593 sysfs_remove_link(&(dev->dev.kobj), linkname); 8594 } 8595 8596 static inline bool netdev_adjacent_is_neigh_list(struct net_device *dev, 8597 struct net_device *adj_dev, 8598 struct list_head *dev_list) 8599 { 8600 return (dev_list == &dev->adj_list.upper || 8601 dev_list == &dev->adj_list.lower) && 8602 net_eq(dev_net(dev), dev_net(adj_dev)); 8603 } 8604 8605 static int __netdev_adjacent_dev_insert(struct net_device *dev, 8606 struct net_device *adj_dev, 8607 struct list_head *dev_list, 8608 void *private, bool master) 8609 { 8610 struct netdev_adjacent *adj; 8611 int ret; 8612 8613 adj = __netdev_find_adj(adj_dev, dev_list); 8614 8615 if (adj) { 8616 adj->ref_nr += 1; 8617 pr_debug("Insert adjacency: dev %s adj_dev %s adj->ref_nr %d\n", 8618 dev->name, adj_dev->name, adj->ref_nr); 8619 8620 return 0; 8621 } 8622 8623 adj = kmalloc(sizeof(*adj), GFP_KERNEL); 8624 if (!adj) 8625 return -ENOMEM; 8626 8627 adj->dev = adj_dev; 8628 adj->master = master; 8629 adj->ref_nr = 1; 8630 adj->private = private; 8631 adj->ignore = false; 8632 netdev_hold(adj_dev, &adj->dev_tracker, GFP_KERNEL); 8633 8634 pr_debug("Insert adjacency: dev %s adj_dev %s adj->ref_nr %d; dev_hold on %s\n", 8635 dev->name, adj_dev->name, adj->ref_nr, adj_dev->name); 8636 8637 if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list)) { 8638 ret = netdev_adjacent_sysfs_add(dev, adj_dev, dev_list); 8639 if (ret) 8640 goto free_adj; 8641 } 8642 8643 /* Ensure that master link is always the first item in list. */ 8644 if (master) { 8645 ret = sysfs_create_link(&(dev->dev.kobj), 8646 &(adj_dev->dev.kobj), "master"); 8647 if (ret) 8648 goto remove_symlinks; 8649 8650 list_add_rcu(&adj->list, dev_list); 8651 } else { 8652 list_add_tail_rcu(&adj->list, dev_list); 8653 } 8654 8655 return 0; 8656 8657 remove_symlinks: 8658 if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list)) 8659 netdev_adjacent_sysfs_del(dev, adj_dev->name, dev_list); 8660 free_adj: 8661 netdev_put(adj_dev, &adj->dev_tracker); 8662 kfree(adj); 8663 8664 return ret; 8665 } 8666 8667 static void __netdev_adjacent_dev_remove(struct net_device *dev, 8668 struct net_device *adj_dev, 8669 u16 ref_nr, 8670 struct list_head *dev_list) 8671 { 8672 struct netdev_adjacent *adj; 8673 8674 pr_debug("Remove adjacency: dev %s adj_dev %s ref_nr %d\n", 8675 dev->name, adj_dev->name, ref_nr); 8676 8677 adj = __netdev_find_adj(adj_dev, dev_list); 8678 8679 if (!adj) { 8680 pr_err("Adjacency does not exist for device %s from %s\n", 8681 dev->name, adj_dev->name); 8682 WARN_ON(1); 8683 return; 8684 } 8685 8686 if (adj->ref_nr > ref_nr) { 8687 pr_debug("adjacency: %s to %s ref_nr - %d = %d\n", 8688 dev->name, adj_dev->name, ref_nr, 8689 adj->ref_nr - ref_nr); 8690 adj->ref_nr -= ref_nr; 8691 return; 8692 } 8693 8694 if (adj->master) 8695 sysfs_remove_link(&(dev->dev.kobj), "master"); 8696 8697 if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list)) 8698 netdev_adjacent_sysfs_del(dev, adj_dev->name, dev_list); 8699 8700 list_del_rcu(&adj->list); 8701 pr_debug("adjacency: dev_put for %s, because link removed from %s to %s\n", 8702 adj_dev->name, dev->name, adj_dev->name); 8703 netdev_put(adj_dev, &adj->dev_tracker); 8704 kfree_rcu(adj, rcu); 8705 } 8706 8707 static int __netdev_adjacent_dev_link_lists(struct net_device *dev, 8708 struct net_device *upper_dev, 8709 struct list_head *up_list, 8710 struct list_head *down_list, 8711 void *private, bool master) 8712 { 8713 int ret; 8714 8715 ret = __netdev_adjacent_dev_insert(dev, upper_dev, up_list, 8716 private, master); 8717 if (ret) 8718 return ret; 8719 8720 ret = __netdev_adjacent_dev_insert(upper_dev, dev, down_list, 8721 private, false); 8722 if (ret) { 8723 __netdev_adjacent_dev_remove(dev, upper_dev, 1, up_list); 8724 return ret; 8725 } 8726 8727 return 0; 8728 } 8729 8730 static void __netdev_adjacent_dev_unlink_lists(struct net_device *dev, 8731 struct net_device *upper_dev, 8732 u16 ref_nr, 8733 struct list_head *up_list, 8734 struct list_head *down_list) 8735 { 8736 __netdev_adjacent_dev_remove(dev, upper_dev, ref_nr, up_list); 8737 __netdev_adjacent_dev_remove(upper_dev, dev, ref_nr, down_list); 8738 } 8739 8740 static int __netdev_adjacent_dev_link_neighbour(struct net_device *dev, 8741 struct net_device *upper_dev, 8742 void *private, bool master) 8743 { 8744 return __netdev_adjacent_dev_link_lists(dev, upper_dev, 8745 &dev->adj_list.upper, 8746 &upper_dev->adj_list.lower, 8747 private, master); 8748 } 8749 8750 static void __netdev_adjacent_dev_unlink_neighbour(struct net_device *dev, 8751 struct net_device *upper_dev) 8752 { 8753 __netdev_adjacent_dev_unlink_lists(dev, upper_dev, 1, 8754 &dev->adj_list.upper, 8755 &upper_dev->adj_list.lower); 8756 } 8757 8758 static int __netdev_upper_dev_link(struct net_device *dev, 8759 struct net_device *upper_dev, bool master, 8760 void *upper_priv, void *upper_info, 8761 struct netdev_nested_priv *priv, 8762 struct netlink_ext_ack *extack) 8763 { 8764 struct netdev_notifier_changeupper_info changeupper_info = { 8765 .info = { 8766 .dev = dev, 8767 .extack = extack, 8768 }, 8769 .upper_dev = upper_dev, 8770 .master = master, 8771 .linking = true, 8772 .upper_info = upper_info, 8773 }; 8774 struct net_device *master_dev; 8775 int ret = 0; 8776 8777 ASSERT_RTNL(); 8778 8779 if (dev == upper_dev) 8780 return -EBUSY; 8781 8782 /* To prevent loops, check if dev is not upper device to upper_dev. */ 8783 if (__netdev_has_upper_dev(upper_dev, dev)) 8784 return -EBUSY; 8785 8786 if ((dev->lower_level + upper_dev->upper_level) > MAX_NEST_DEV) 8787 return -EMLINK; 8788 8789 if (!master) { 8790 if (__netdev_has_upper_dev(dev, upper_dev)) 8791 return -EEXIST; 8792 } else { 8793 master_dev = __netdev_master_upper_dev_get(dev); 8794 if (master_dev) 8795 return master_dev == upper_dev ? -EEXIST : -EBUSY; 8796 } 8797 8798 ret = call_netdevice_notifiers_info(NETDEV_PRECHANGEUPPER, 8799 &changeupper_info.info); 8800 ret = notifier_to_errno(ret); 8801 if (ret) 8802 return ret; 8803 8804 ret = __netdev_adjacent_dev_link_neighbour(dev, upper_dev, upper_priv, 8805 master); 8806 if (ret) 8807 return ret; 8808 8809 ret = call_netdevice_notifiers_info(NETDEV_CHANGEUPPER, 8810 &changeupper_info.info); 8811 ret = notifier_to_errno(ret); 8812 if (ret) 8813 goto rollback; 8814 8815 __netdev_update_upper_level(dev, NULL); 8816 __netdev_walk_all_lower_dev(dev, __netdev_update_upper_level, NULL); 8817 8818 __netdev_update_lower_level(upper_dev, priv); 8819 __netdev_walk_all_upper_dev(upper_dev, __netdev_update_lower_level, 8820 priv); 8821 8822 return 0; 8823 8824 rollback: 8825 __netdev_adjacent_dev_unlink_neighbour(dev, upper_dev); 8826 8827 return ret; 8828 } 8829 8830 /** 8831 * netdev_upper_dev_link - Add a link to the upper device 8832 * @dev: device 8833 * @upper_dev: new upper device 8834 * @extack: netlink extended ack 8835 * 8836 * Adds a link to device which is upper to this one. The caller must hold 8837 * the RTNL lock. On a failure a negative errno code is returned. 8838 * On success the reference counts are adjusted and the function 8839 * returns zero. 8840 */ 8841 int netdev_upper_dev_link(struct net_device *dev, 8842 struct net_device *upper_dev, 8843 struct netlink_ext_ack *extack) 8844 { 8845 struct netdev_nested_priv priv = { 8846 .flags = NESTED_SYNC_IMM | NESTED_SYNC_TODO, 8847 .data = NULL, 8848 }; 8849 8850 return __netdev_upper_dev_link(dev, upper_dev, false, 8851 NULL, NULL, &priv, extack); 8852 } 8853 EXPORT_SYMBOL(netdev_upper_dev_link); 8854 8855 /** 8856 * netdev_master_upper_dev_link - Add a master link to the upper device 8857 * @dev: device 8858 * @upper_dev: new upper device 8859 * @upper_priv: upper device private 8860 * @upper_info: upper info to be passed down via notifier 8861 * @extack: netlink extended ack 8862 * 8863 * Adds a link to device which is upper to this one. In this case, only 8864 * one master upper device can be linked, although other non-master devices 8865 * might be linked as well. The caller must hold the RTNL lock. 8866 * On a failure a negative errno code is returned. On success the reference 8867 * counts are adjusted and the function returns zero. 8868 */ 8869 int netdev_master_upper_dev_link(struct net_device *dev, 8870 struct net_device *upper_dev, 8871 void *upper_priv, void *upper_info, 8872 struct netlink_ext_ack *extack) 8873 { 8874 struct netdev_nested_priv priv = { 8875 .flags = NESTED_SYNC_IMM | NESTED_SYNC_TODO, 8876 .data = NULL, 8877 }; 8878 8879 return __netdev_upper_dev_link(dev, upper_dev, true, 8880 upper_priv, upper_info, &priv, extack); 8881 } 8882 EXPORT_SYMBOL(netdev_master_upper_dev_link); 8883 8884 static void __netdev_upper_dev_unlink(struct net_device *dev, 8885 struct net_device *upper_dev, 8886 struct netdev_nested_priv *priv) 8887 { 8888 struct netdev_notifier_changeupper_info changeupper_info = { 8889 .info = { 8890 .dev = dev, 8891 }, 8892 .upper_dev = upper_dev, 8893 .linking = false, 8894 }; 8895 8896 ASSERT_RTNL(); 8897 8898 changeupper_info.master = netdev_master_upper_dev_get(dev) == upper_dev; 8899 8900 call_netdevice_notifiers_info(NETDEV_PRECHANGEUPPER, 8901 &changeupper_info.info); 8902 8903 __netdev_adjacent_dev_unlink_neighbour(dev, upper_dev); 8904 8905 call_netdevice_notifiers_info(NETDEV_CHANGEUPPER, 8906 &changeupper_info.info); 8907 8908 __netdev_update_upper_level(dev, NULL); 8909 __netdev_walk_all_lower_dev(dev, __netdev_update_upper_level, NULL); 8910 8911 __netdev_update_lower_level(upper_dev, priv); 8912 __netdev_walk_all_upper_dev(upper_dev, __netdev_update_lower_level, 8913 priv); 8914 } 8915 8916 /** 8917 * netdev_upper_dev_unlink - Removes a link to upper device 8918 * @dev: device 8919 * @upper_dev: new upper device 8920 * 8921 * Removes a link to device which is upper to this one. The caller must hold 8922 * the RTNL lock. 8923 */ 8924 void netdev_upper_dev_unlink(struct net_device *dev, 8925 struct net_device *upper_dev) 8926 { 8927 struct netdev_nested_priv priv = { 8928 .flags = NESTED_SYNC_TODO, 8929 .data = NULL, 8930 }; 8931 8932 __netdev_upper_dev_unlink(dev, upper_dev, &priv); 8933 } 8934 EXPORT_SYMBOL(netdev_upper_dev_unlink); 8935 8936 static void __netdev_adjacent_dev_set(struct net_device *upper_dev, 8937 struct net_device *lower_dev, 8938 bool val) 8939 { 8940 struct netdev_adjacent *adj; 8941 8942 adj = __netdev_find_adj(lower_dev, &upper_dev->adj_list.lower); 8943 if (adj) 8944 adj->ignore = val; 8945 8946 adj = __netdev_find_adj(upper_dev, &lower_dev->adj_list.upper); 8947 if (adj) 8948 adj->ignore = val; 8949 } 8950 8951 static void netdev_adjacent_dev_disable(struct net_device *upper_dev, 8952 struct net_device *lower_dev) 8953 { 8954 __netdev_adjacent_dev_set(upper_dev, lower_dev, true); 8955 } 8956 8957 static void netdev_adjacent_dev_enable(struct net_device *upper_dev, 8958 struct net_device *lower_dev) 8959 { 8960 __netdev_adjacent_dev_set(upper_dev, lower_dev, false); 8961 } 8962 8963 int netdev_adjacent_change_prepare(struct net_device *old_dev, 8964 struct net_device *new_dev, 8965 struct net_device *dev, 8966 struct netlink_ext_ack *extack) 8967 { 8968 struct netdev_nested_priv priv = { 8969 .flags = 0, 8970 .data = NULL, 8971 }; 8972 int err; 8973 8974 if (!new_dev) 8975 return 0; 8976 8977 if (old_dev && new_dev != old_dev) 8978 netdev_adjacent_dev_disable(dev, old_dev); 8979 err = __netdev_upper_dev_link(new_dev, dev, false, NULL, NULL, &priv, 8980 extack); 8981 if (err) { 8982 if (old_dev && new_dev != old_dev) 8983 netdev_adjacent_dev_enable(dev, old_dev); 8984 return err; 8985 } 8986 8987 return 0; 8988 } 8989 EXPORT_SYMBOL(netdev_adjacent_change_prepare); 8990 8991 void netdev_adjacent_change_commit(struct net_device *old_dev, 8992 struct net_device *new_dev, 8993 struct net_device *dev) 8994 { 8995 struct netdev_nested_priv priv = { 8996 .flags = NESTED_SYNC_IMM | NESTED_SYNC_TODO, 8997 .data = NULL, 8998 }; 8999 9000 if (!new_dev || !old_dev) 9001 return; 9002 9003 if (new_dev == old_dev) 9004 return; 9005 9006 netdev_adjacent_dev_enable(dev, old_dev); 9007 __netdev_upper_dev_unlink(old_dev, dev, &priv); 9008 } 9009 EXPORT_SYMBOL(netdev_adjacent_change_commit); 9010 9011 void netdev_adjacent_change_abort(struct net_device *old_dev, 9012 struct net_device *new_dev, 9013 struct net_device *dev) 9014 { 9015 struct netdev_nested_priv priv = { 9016 .flags = 0, 9017 .data = NULL, 9018 }; 9019 9020 if (!new_dev) 9021 return; 9022 9023 if (old_dev && new_dev != old_dev) 9024 netdev_adjacent_dev_enable(dev, old_dev); 9025 9026 __netdev_upper_dev_unlink(new_dev, dev, &priv); 9027 } 9028 EXPORT_SYMBOL(netdev_adjacent_change_abort); 9029 9030 /** 9031 * netdev_bonding_info_change - Dispatch event about slave change 9032 * @dev: device 9033 * @bonding_info: info to dispatch 9034 * 9035 * Send NETDEV_BONDING_INFO to netdev notifiers with info. 9036 * The caller must hold the RTNL lock. 9037 */ 9038 void netdev_bonding_info_change(struct net_device *dev, 9039 struct netdev_bonding_info *bonding_info) 9040 { 9041 struct netdev_notifier_bonding_info info = { 9042 .info.dev = dev, 9043 }; 9044 9045 memcpy(&info.bonding_info, bonding_info, 9046 sizeof(struct netdev_bonding_info)); 9047 call_netdevice_notifiers_info(NETDEV_BONDING_INFO, 9048 &info.info); 9049 } 9050 EXPORT_SYMBOL(netdev_bonding_info_change); 9051 9052 static int netdev_offload_xstats_enable_l3(struct net_device *dev, 9053 struct netlink_ext_ack *extack) 9054 { 9055 struct netdev_notifier_offload_xstats_info info = { 9056 .info.dev = dev, 9057 .info.extack = extack, 9058 .type = NETDEV_OFFLOAD_XSTATS_TYPE_L3, 9059 }; 9060 int err; 9061 int rc; 9062 9063 dev->offload_xstats_l3 = kzalloc(sizeof(*dev->offload_xstats_l3), 9064 GFP_KERNEL); 9065 if (!dev->offload_xstats_l3) 9066 return -ENOMEM; 9067 9068 rc = call_netdevice_notifiers_info_robust(NETDEV_OFFLOAD_XSTATS_ENABLE, 9069 NETDEV_OFFLOAD_XSTATS_DISABLE, 9070 &info.info); 9071 err = notifier_to_errno(rc); 9072 if (err) 9073 goto free_stats; 9074 9075 return 0; 9076 9077 free_stats: 9078 kfree(dev->offload_xstats_l3); 9079 dev->offload_xstats_l3 = NULL; 9080 return err; 9081 } 9082 9083 int netdev_offload_xstats_enable(struct net_device *dev, 9084 enum netdev_offload_xstats_type type, 9085 struct netlink_ext_ack *extack) 9086 { 9087 ASSERT_RTNL(); 9088 9089 if (netdev_offload_xstats_enabled(dev, type)) 9090 return -EALREADY; 9091 9092 switch (type) { 9093 case NETDEV_OFFLOAD_XSTATS_TYPE_L3: 9094 return netdev_offload_xstats_enable_l3(dev, extack); 9095 } 9096 9097 WARN_ON(1); 9098 return -EINVAL; 9099 } 9100 EXPORT_SYMBOL(netdev_offload_xstats_enable); 9101 9102 static void netdev_offload_xstats_disable_l3(struct net_device *dev) 9103 { 9104 struct netdev_notifier_offload_xstats_info info = { 9105 .info.dev = dev, 9106 .type = NETDEV_OFFLOAD_XSTATS_TYPE_L3, 9107 }; 9108 9109 call_netdevice_notifiers_info(NETDEV_OFFLOAD_XSTATS_DISABLE, 9110 &info.info); 9111 kfree(dev->offload_xstats_l3); 9112 dev->offload_xstats_l3 = NULL; 9113 } 9114 9115 int netdev_offload_xstats_disable(struct net_device *dev, 9116 enum netdev_offload_xstats_type type) 9117 { 9118 ASSERT_RTNL(); 9119 9120 if (!netdev_offload_xstats_enabled(dev, type)) 9121 return -EALREADY; 9122 9123 switch (type) { 9124 case NETDEV_OFFLOAD_XSTATS_TYPE_L3: 9125 netdev_offload_xstats_disable_l3(dev); 9126 return 0; 9127 } 9128 9129 WARN_ON(1); 9130 return -EINVAL; 9131 } 9132 EXPORT_SYMBOL(netdev_offload_xstats_disable); 9133 9134 static void netdev_offload_xstats_disable_all(struct net_device *dev) 9135 { 9136 netdev_offload_xstats_disable(dev, NETDEV_OFFLOAD_XSTATS_TYPE_L3); 9137 } 9138 9139 static struct rtnl_hw_stats64 * 9140 netdev_offload_xstats_get_ptr(const struct net_device *dev, 9141 enum netdev_offload_xstats_type type) 9142 { 9143 switch (type) { 9144 case NETDEV_OFFLOAD_XSTATS_TYPE_L3: 9145 return dev->offload_xstats_l3; 9146 } 9147 9148 WARN_ON(1); 9149 return NULL; 9150 } 9151 9152 bool netdev_offload_xstats_enabled(const struct net_device *dev, 9153 enum netdev_offload_xstats_type type) 9154 { 9155 ASSERT_RTNL(); 9156 9157 return netdev_offload_xstats_get_ptr(dev, type); 9158 } 9159 EXPORT_SYMBOL(netdev_offload_xstats_enabled); 9160 9161 struct netdev_notifier_offload_xstats_ru { 9162 bool used; 9163 }; 9164 9165 struct netdev_notifier_offload_xstats_rd { 9166 struct rtnl_hw_stats64 stats; 9167 bool used; 9168 }; 9169 9170 static void netdev_hw_stats64_add(struct rtnl_hw_stats64 *dest, 9171 const struct rtnl_hw_stats64 *src) 9172 { 9173 dest->rx_packets += src->rx_packets; 9174 dest->tx_packets += src->tx_packets; 9175 dest->rx_bytes += src->rx_bytes; 9176 dest->tx_bytes += src->tx_bytes; 9177 dest->rx_errors += src->rx_errors; 9178 dest->tx_errors += src->tx_errors; 9179 dest->rx_dropped += src->rx_dropped; 9180 dest->tx_dropped += src->tx_dropped; 9181 dest->multicast += src->multicast; 9182 } 9183 9184 static int netdev_offload_xstats_get_used(struct net_device *dev, 9185 enum netdev_offload_xstats_type type, 9186 bool *p_used, 9187 struct netlink_ext_ack *extack) 9188 { 9189 struct netdev_notifier_offload_xstats_ru report_used = {}; 9190 struct netdev_notifier_offload_xstats_info info = { 9191 .info.dev = dev, 9192 .info.extack = extack, 9193 .type = type, 9194 .report_used = &report_used, 9195 }; 9196 int rc; 9197 9198 WARN_ON(!netdev_offload_xstats_enabled(dev, type)); 9199 rc = call_netdevice_notifiers_info(NETDEV_OFFLOAD_XSTATS_REPORT_USED, 9200 &info.info); 9201 *p_used = report_used.used; 9202 return notifier_to_errno(rc); 9203 } 9204 9205 static int netdev_offload_xstats_get_stats(struct net_device *dev, 9206 enum netdev_offload_xstats_type type, 9207 struct rtnl_hw_stats64 *p_stats, 9208 bool *p_used, 9209 struct netlink_ext_ack *extack) 9210 { 9211 struct netdev_notifier_offload_xstats_rd report_delta = {}; 9212 struct netdev_notifier_offload_xstats_info info = { 9213 .info.dev = dev, 9214 .info.extack = extack, 9215 .type = type, 9216 .report_delta = &report_delta, 9217 }; 9218 struct rtnl_hw_stats64 *stats; 9219 int rc; 9220 9221 stats = netdev_offload_xstats_get_ptr(dev, type); 9222 if (WARN_ON(!stats)) 9223 return -EINVAL; 9224 9225 rc = call_netdevice_notifiers_info(NETDEV_OFFLOAD_XSTATS_REPORT_DELTA, 9226 &info.info); 9227 9228 /* Cache whatever we got, even if there was an error, otherwise the 9229 * successful stats retrievals would get lost. 9230 */ 9231 netdev_hw_stats64_add(stats, &report_delta.stats); 9232 9233 if (p_stats) 9234 *p_stats = *stats; 9235 *p_used = report_delta.used; 9236 9237 return notifier_to_errno(rc); 9238 } 9239 9240 int netdev_offload_xstats_get(struct net_device *dev, 9241 enum netdev_offload_xstats_type type, 9242 struct rtnl_hw_stats64 *p_stats, bool *p_used, 9243 struct netlink_ext_ack *extack) 9244 { 9245 ASSERT_RTNL(); 9246 9247 if (p_stats) 9248 return netdev_offload_xstats_get_stats(dev, type, p_stats, 9249 p_used, extack); 9250 else 9251 return netdev_offload_xstats_get_used(dev, type, p_used, 9252 extack); 9253 } 9254 EXPORT_SYMBOL(netdev_offload_xstats_get); 9255 9256 void 9257 netdev_offload_xstats_report_delta(struct netdev_notifier_offload_xstats_rd *report_delta, 9258 const struct rtnl_hw_stats64 *stats) 9259 { 9260 report_delta->used = true; 9261 netdev_hw_stats64_add(&report_delta->stats, stats); 9262 } 9263 EXPORT_SYMBOL(netdev_offload_xstats_report_delta); 9264 9265 void 9266 netdev_offload_xstats_report_used(struct netdev_notifier_offload_xstats_ru *report_used) 9267 { 9268 report_used->used = true; 9269 } 9270 EXPORT_SYMBOL(netdev_offload_xstats_report_used); 9271 9272 void netdev_offload_xstats_push_delta(struct net_device *dev, 9273 enum netdev_offload_xstats_type type, 9274 const struct rtnl_hw_stats64 *p_stats) 9275 { 9276 struct rtnl_hw_stats64 *stats; 9277 9278 ASSERT_RTNL(); 9279 9280 stats = netdev_offload_xstats_get_ptr(dev, type); 9281 if (WARN_ON(!stats)) 9282 return; 9283 9284 netdev_hw_stats64_add(stats, p_stats); 9285 } 9286 EXPORT_SYMBOL(netdev_offload_xstats_push_delta); 9287 9288 /** 9289 * netdev_get_xmit_slave - Get the xmit slave of master device 9290 * @dev: device 9291 * @skb: The packet 9292 * @all_slaves: assume all the slaves are active 9293 * 9294 * The reference counters are not incremented so the caller must be 9295 * careful with locks. The caller must hold RCU lock. 9296 * %NULL is returned if no slave is found. 9297 */ 9298 9299 struct net_device *netdev_get_xmit_slave(struct net_device *dev, 9300 struct sk_buff *skb, 9301 bool all_slaves) 9302 { 9303 const struct net_device_ops *ops = dev->netdev_ops; 9304 9305 if (!ops->ndo_get_xmit_slave) 9306 return NULL; 9307 return ops->ndo_get_xmit_slave(dev, skb, all_slaves); 9308 } 9309 EXPORT_SYMBOL(netdev_get_xmit_slave); 9310 9311 static struct net_device *netdev_sk_get_lower_dev(struct net_device *dev, 9312 struct sock *sk) 9313 { 9314 const struct net_device_ops *ops = dev->netdev_ops; 9315 9316 if (!ops->ndo_sk_get_lower_dev) 9317 return NULL; 9318 return ops->ndo_sk_get_lower_dev(dev, sk); 9319 } 9320 9321 /** 9322 * netdev_sk_get_lowest_dev - Get the lowest device in chain given device and socket 9323 * @dev: device 9324 * @sk: the socket 9325 * 9326 * %NULL is returned if no lower device is found. 9327 */ 9328 9329 struct net_device *netdev_sk_get_lowest_dev(struct net_device *dev, 9330 struct sock *sk) 9331 { 9332 struct net_device *lower; 9333 9334 lower = netdev_sk_get_lower_dev(dev, sk); 9335 while (lower) { 9336 dev = lower; 9337 lower = netdev_sk_get_lower_dev(dev, sk); 9338 } 9339 9340 return dev; 9341 } 9342 EXPORT_SYMBOL(netdev_sk_get_lowest_dev); 9343 9344 static void netdev_adjacent_add_links(struct net_device *dev) 9345 { 9346 struct netdev_adjacent *iter; 9347 9348 struct net *net = dev_net(dev); 9349 9350 list_for_each_entry(iter, &dev->adj_list.upper, list) { 9351 if (!net_eq(net, dev_net(iter->dev))) 9352 continue; 9353 netdev_adjacent_sysfs_add(iter->dev, dev, 9354 &iter->dev->adj_list.lower); 9355 netdev_adjacent_sysfs_add(dev, iter->dev, 9356 &dev->adj_list.upper); 9357 } 9358 9359 list_for_each_entry(iter, &dev->adj_list.lower, list) { 9360 if (!net_eq(net, dev_net(iter->dev))) 9361 continue; 9362 netdev_adjacent_sysfs_add(iter->dev, dev, 9363 &iter->dev->adj_list.upper); 9364 netdev_adjacent_sysfs_add(dev, iter->dev, 9365 &dev->adj_list.lower); 9366 } 9367 } 9368 9369 static void netdev_adjacent_del_links(struct net_device *dev) 9370 { 9371 struct netdev_adjacent *iter; 9372 9373 struct net *net = dev_net(dev); 9374 9375 list_for_each_entry(iter, &dev->adj_list.upper, list) { 9376 if (!net_eq(net, dev_net(iter->dev))) 9377 continue; 9378 netdev_adjacent_sysfs_del(iter->dev, dev->name, 9379 &iter->dev->adj_list.lower); 9380 netdev_adjacent_sysfs_del(dev, iter->dev->name, 9381 &dev->adj_list.upper); 9382 } 9383 9384 list_for_each_entry(iter, &dev->adj_list.lower, list) { 9385 if (!net_eq(net, dev_net(iter->dev))) 9386 continue; 9387 netdev_adjacent_sysfs_del(iter->dev, dev->name, 9388 &iter->dev->adj_list.upper); 9389 netdev_adjacent_sysfs_del(dev, iter->dev->name, 9390 &dev->adj_list.lower); 9391 } 9392 } 9393 9394 void netdev_adjacent_rename_links(struct net_device *dev, char *oldname) 9395 { 9396 struct netdev_adjacent *iter; 9397 9398 struct net *net = dev_net(dev); 9399 9400 list_for_each_entry(iter, &dev->adj_list.upper, list) { 9401 if (!net_eq(net, dev_net(iter->dev))) 9402 continue; 9403 netdev_adjacent_sysfs_del(iter->dev, oldname, 9404 &iter->dev->adj_list.lower); 9405 netdev_adjacent_sysfs_add(iter->dev, dev, 9406 &iter->dev->adj_list.lower); 9407 } 9408 9409 list_for_each_entry(iter, &dev->adj_list.lower, list) { 9410 if (!net_eq(net, dev_net(iter->dev))) 9411 continue; 9412 netdev_adjacent_sysfs_del(iter->dev, oldname, 9413 &iter->dev->adj_list.upper); 9414 netdev_adjacent_sysfs_add(iter->dev, dev, 9415 &iter->dev->adj_list.upper); 9416 } 9417 } 9418 9419 void *netdev_lower_dev_get_private(struct net_device *dev, 9420 struct net_device *lower_dev) 9421 { 9422 struct netdev_adjacent *lower; 9423 9424 if (!lower_dev) 9425 return NULL; 9426 lower = __netdev_find_adj(lower_dev, &dev->adj_list.lower); 9427 if (!lower) 9428 return NULL; 9429 9430 return lower->private; 9431 } 9432 EXPORT_SYMBOL(netdev_lower_dev_get_private); 9433 9434 9435 /** 9436 * netdev_lower_state_changed - Dispatch event about lower device state change 9437 * @lower_dev: device 9438 * @lower_state_info: state to dispatch 9439 * 9440 * Send NETDEV_CHANGELOWERSTATE to netdev notifiers with info. 9441 * The caller must hold the RTNL lock. 9442 */ 9443 void netdev_lower_state_changed(struct net_device *lower_dev, 9444 void *lower_state_info) 9445 { 9446 struct netdev_notifier_changelowerstate_info changelowerstate_info = { 9447 .info.dev = lower_dev, 9448 }; 9449 9450 ASSERT_RTNL(); 9451 changelowerstate_info.lower_state_info = lower_state_info; 9452 call_netdevice_notifiers_info(NETDEV_CHANGELOWERSTATE, 9453 &changelowerstate_info.info); 9454 } 9455 EXPORT_SYMBOL(netdev_lower_state_changed); 9456 9457 static void dev_change_rx_flags(struct net_device *dev, int flags) 9458 { 9459 const struct net_device_ops *ops = dev->netdev_ops; 9460 9461 if (ops->ndo_change_rx_flags) 9462 ops->ndo_change_rx_flags(dev, flags); 9463 } 9464 9465 static int __dev_set_promiscuity(struct net_device *dev, int inc, bool notify) 9466 { 9467 unsigned int old_flags = dev->flags; 9468 unsigned int promiscuity, flags; 9469 kuid_t uid; 9470 kgid_t gid; 9471 9472 ASSERT_RTNL(); 9473 9474 promiscuity = dev->promiscuity + inc; 9475 if (promiscuity == 0) { 9476 /* 9477 * Avoid overflow. 9478 * If inc causes overflow, untouch promisc and return error. 9479 */ 9480 if (unlikely(inc > 0)) { 9481 netdev_warn(dev, "promiscuity touches roof, set promiscuity failed. promiscuity feature of device might be broken.\n"); 9482 return -EOVERFLOW; 9483 } 9484 flags = old_flags & ~IFF_PROMISC; 9485 } else { 9486 flags = old_flags | IFF_PROMISC; 9487 } 9488 WRITE_ONCE(dev->promiscuity, promiscuity); 9489 if (flags != old_flags) { 9490 WRITE_ONCE(dev->flags, flags); 9491 netdev_info(dev, "%s promiscuous mode\n", 9492 dev->flags & IFF_PROMISC ? "entered" : "left"); 9493 if (audit_enabled) { 9494 current_uid_gid(&uid, &gid); 9495 audit_log(audit_context(), GFP_ATOMIC, 9496 AUDIT_ANOM_PROMISCUOUS, 9497 "dev=%s prom=%d old_prom=%d auid=%u uid=%u gid=%u ses=%u", 9498 dev->name, (dev->flags & IFF_PROMISC), 9499 (old_flags & IFF_PROMISC), 9500 from_kuid(&init_user_ns, audit_get_loginuid(current)), 9501 from_kuid(&init_user_ns, uid), 9502 from_kgid(&init_user_ns, gid), 9503 audit_get_sessionid(current)); 9504 } 9505 9506 dev_change_rx_flags(dev, IFF_PROMISC); 9507 } 9508 if (notify) { 9509 /* The ops lock is only required to ensure consistent locking 9510 * for `NETDEV_CHANGE` notifiers. This function is sometimes 9511 * called without the lock, even for devices that are ops 9512 * locked, such as in `dev_uc_sync_multiple` when using 9513 * bonding or teaming. 9514 */ 9515 netdev_ops_assert_locked(dev); 9516 __dev_notify_flags(dev, old_flags, IFF_PROMISC, 0, NULL); 9517 } 9518 return 0; 9519 } 9520 9521 int netif_set_promiscuity(struct net_device *dev, int inc) 9522 { 9523 unsigned int old_flags = dev->flags; 9524 int err; 9525 9526 err = __dev_set_promiscuity(dev, inc, true); 9527 if (err < 0) 9528 return err; 9529 if (dev->flags != old_flags) 9530 dev_set_rx_mode(dev); 9531 return err; 9532 } 9533 9534 int netif_set_allmulti(struct net_device *dev, int inc, bool notify) 9535 { 9536 unsigned int old_flags = dev->flags, old_gflags = dev->gflags; 9537 unsigned int allmulti, flags; 9538 9539 ASSERT_RTNL(); 9540 9541 allmulti = dev->allmulti + inc; 9542 if (allmulti == 0) { 9543 /* 9544 * Avoid overflow. 9545 * If inc causes overflow, untouch allmulti and return error. 9546 */ 9547 if (unlikely(inc > 0)) { 9548 netdev_warn(dev, "allmulti touches roof, set allmulti failed. allmulti feature of device might be broken.\n"); 9549 return -EOVERFLOW; 9550 } 9551 flags = old_flags & ~IFF_ALLMULTI; 9552 } else { 9553 flags = old_flags | IFF_ALLMULTI; 9554 } 9555 WRITE_ONCE(dev->allmulti, allmulti); 9556 if (flags != old_flags) { 9557 WRITE_ONCE(dev->flags, flags); 9558 netdev_info(dev, "%s allmulticast mode\n", 9559 dev->flags & IFF_ALLMULTI ? "entered" : "left"); 9560 dev_change_rx_flags(dev, IFF_ALLMULTI); 9561 dev_set_rx_mode(dev); 9562 if (notify) 9563 __dev_notify_flags(dev, old_flags, 9564 dev->gflags ^ old_gflags, 0, NULL); 9565 } 9566 return 0; 9567 } 9568 9569 /* 9570 * Upload unicast and multicast address lists to device and 9571 * configure RX filtering. When the device doesn't support unicast 9572 * filtering it is put in promiscuous mode while unicast addresses 9573 * are present. 9574 */ 9575 void __dev_set_rx_mode(struct net_device *dev) 9576 { 9577 const struct net_device_ops *ops = dev->netdev_ops; 9578 9579 /* dev_open will call this function so the list will stay sane. */ 9580 if (!(dev->flags&IFF_UP)) 9581 return; 9582 9583 if (!netif_device_present(dev)) 9584 return; 9585 9586 if (!(dev->priv_flags & IFF_UNICAST_FLT)) { 9587 /* Unicast addresses changes may only happen under the rtnl, 9588 * therefore calling __dev_set_promiscuity here is safe. 9589 */ 9590 if (!netdev_uc_empty(dev) && !dev->uc_promisc) { 9591 __dev_set_promiscuity(dev, 1, false); 9592 dev->uc_promisc = true; 9593 } else if (netdev_uc_empty(dev) && dev->uc_promisc) { 9594 __dev_set_promiscuity(dev, -1, false); 9595 dev->uc_promisc = false; 9596 } 9597 } 9598 9599 if (ops->ndo_set_rx_mode) 9600 ops->ndo_set_rx_mode(dev); 9601 } 9602 9603 void dev_set_rx_mode(struct net_device *dev) 9604 { 9605 netif_addr_lock_bh(dev); 9606 __dev_set_rx_mode(dev); 9607 netif_addr_unlock_bh(dev); 9608 } 9609 9610 /** 9611 * netif_get_flags() - get flags reported to userspace 9612 * @dev: device 9613 * 9614 * Get the combination of flag bits exported through APIs to userspace. 9615 */ 9616 unsigned int netif_get_flags(const struct net_device *dev) 9617 { 9618 unsigned int flags; 9619 9620 flags = (READ_ONCE(dev->flags) & ~(IFF_PROMISC | 9621 IFF_ALLMULTI | 9622 IFF_RUNNING | 9623 IFF_LOWER_UP | 9624 IFF_DORMANT)) | 9625 (READ_ONCE(dev->gflags) & (IFF_PROMISC | 9626 IFF_ALLMULTI)); 9627 9628 if (netif_running(dev)) { 9629 if (netif_oper_up(dev)) 9630 flags |= IFF_RUNNING; 9631 if (netif_carrier_ok(dev)) 9632 flags |= IFF_LOWER_UP; 9633 if (netif_dormant(dev)) 9634 flags |= IFF_DORMANT; 9635 } 9636 9637 return flags; 9638 } 9639 EXPORT_SYMBOL(netif_get_flags); 9640 9641 int __dev_change_flags(struct net_device *dev, unsigned int flags, 9642 struct netlink_ext_ack *extack) 9643 { 9644 unsigned int old_flags = dev->flags; 9645 int ret; 9646 9647 ASSERT_RTNL(); 9648 9649 /* 9650 * Set the flags on our device. 9651 */ 9652 9653 dev->flags = (flags & (IFF_DEBUG | IFF_NOTRAILERS | IFF_NOARP | 9654 IFF_DYNAMIC | IFF_MULTICAST | IFF_PORTSEL | 9655 IFF_AUTOMEDIA)) | 9656 (dev->flags & (IFF_UP | IFF_VOLATILE | IFF_PROMISC | 9657 IFF_ALLMULTI)); 9658 9659 /* 9660 * Load in the correct multicast list now the flags have changed. 9661 */ 9662 9663 if ((old_flags ^ flags) & IFF_MULTICAST) 9664 dev_change_rx_flags(dev, IFF_MULTICAST); 9665 9666 dev_set_rx_mode(dev); 9667 9668 /* 9669 * Have we downed the interface. We handle IFF_UP ourselves 9670 * according to user attempts to set it, rather than blindly 9671 * setting it. 9672 */ 9673 9674 ret = 0; 9675 if ((old_flags ^ flags) & IFF_UP) { 9676 if (old_flags & IFF_UP) 9677 __dev_close(dev); 9678 else 9679 ret = __dev_open(dev, extack); 9680 } 9681 9682 if ((flags ^ dev->gflags) & IFF_PROMISC) { 9683 int inc = (flags & IFF_PROMISC) ? 1 : -1; 9684 old_flags = dev->flags; 9685 9686 dev->gflags ^= IFF_PROMISC; 9687 9688 if (__dev_set_promiscuity(dev, inc, false) >= 0) 9689 if (dev->flags != old_flags) 9690 dev_set_rx_mode(dev); 9691 } 9692 9693 /* NOTE: order of synchronization of IFF_PROMISC and IFF_ALLMULTI 9694 * is important. Some (broken) drivers set IFF_PROMISC, when 9695 * IFF_ALLMULTI is requested not asking us and not reporting. 9696 */ 9697 if ((flags ^ dev->gflags) & IFF_ALLMULTI) { 9698 int inc = (flags & IFF_ALLMULTI) ? 1 : -1; 9699 9700 dev->gflags ^= IFF_ALLMULTI; 9701 netif_set_allmulti(dev, inc, false); 9702 } 9703 9704 return ret; 9705 } 9706 9707 void __dev_notify_flags(struct net_device *dev, unsigned int old_flags, 9708 unsigned int gchanges, u32 portid, 9709 const struct nlmsghdr *nlh) 9710 { 9711 unsigned int changes = dev->flags ^ old_flags; 9712 9713 if (gchanges) 9714 rtmsg_ifinfo(RTM_NEWLINK, dev, gchanges, GFP_ATOMIC, portid, nlh); 9715 9716 if (changes & IFF_UP) { 9717 if (dev->flags & IFF_UP) 9718 call_netdevice_notifiers(NETDEV_UP, dev); 9719 else 9720 call_netdevice_notifiers(NETDEV_DOWN, dev); 9721 } 9722 9723 if (dev->flags & IFF_UP && 9724 (changes & ~(IFF_UP | IFF_PROMISC | IFF_ALLMULTI | IFF_VOLATILE))) { 9725 struct netdev_notifier_change_info change_info = { 9726 .info = { 9727 .dev = dev, 9728 }, 9729 .flags_changed = changes, 9730 }; 9731 9732 call_netdevice_notifiers_info(NETDEV_CHANGE, &change_info.info); 9733 } 9734 } 9735 9736 int netif_change_flags(struct net_device *dev, unsigned int flags, 9737 struct netlink_ext_ack *extack) 9738 { 9739 int ret; 9740 unsigned int changes, old_flags = dev->flags, old_gflags = dev->gflags; 9741 9742 ret = __dev_change_flags(dev, flags, extack); 9743 if (ret < 0) 9744 return ret; 9745 9746 changes = (old_flags ^ dev->flags) | (old_gflags ^ dev->gflags); 9747 __dev_notify_flags(dev, old_flags, changes, 0, NULL); 9748 return ret; 9749 } 9750 9751 int __netif_set_mtu(struct net_device *dev, int new_mtu) 9752 { 9753 const struct net_device_ops *ops = dev->netdev_ops; 9754 9755 if (ops->ndo_change_mtu) 9756 return ops->ndo_change_mtu(dev, new_mtu); 9757 9758 /* Pairs with all the lockless reads of dev->mtu in the stack */ 9759 WRITE_ONCE(dev->mtu, new_mtu); 9760 return 0; 9761 } 9762 EXPORT_SYMBOL_NS_GPL(__netif_set_mtu, "NETDEV_INTERNAL"); 9763 9764 int dev_validate_mtu(struct net_device *dev, int new_mtu, 9765 struct netlink_ext_ack *extack) 9766 { 9767 /* MTU must be positive, and in range */ 9768 if (new_mtu < 0 || new_mtu < dev->min_mtu) { 9769 NL_SET_ERR_MSG(extack, "mtu less than device minimum"); 9770 return -EINVAL; 9771 } 9772 9773 if (dev->max_mtu > 0 && new_mtu > dev->max_mtu) { 9774 NL_SET_ERR_MSG(extack, "mtu greater than device maximum"); 9775 return -EINVAL; 9776 } 9777 return 0; 9778 } 9779 9780 /** 9781 * netif_set_mtu_ext() - Change maximum transfer unit 9782 * @dev: device 9783 * @new_mtu: new transfer unit 9784 * @extack: netlink extended ack 9785 * 9786 * Change the maximum transfer size of the network device. 9787 * 9788 * Return: 0 on success, -errno on failure. 9789 */ 9790 int netif_set_mtu_ext(struct net_device *dev, int new_mtu, 9791 struct netlink_ext_ack *extack) 9792 { 9793 int err, orig_mtu; 9794 9795 netdev_ops_assert_locked(dev); 9796 9797 if (new_mtu == dev->mtu) 9798 return 0; 9799 9800 err = dev_validate_mtu(dev, new_mtu, extack); 9801 if (err) 9802 return err; 9803 9804 if (!netif_device_present(dev)) 9805 return -ENODEV; 9806 9807 err = call_netdevice_notifiers(NETDEV_PRECHANGEMTU, dev); 9808 err = notifier_to_errno(err); 9809 if (err) 9810 return err; 9811 9812 orig_mtu = dev->mtu; 9813 err = __netif_set_mtu(dev, new_mtu); 9814 9815 if (!err) { 9816 err = call_netdevice_notifiers_mtu(NETDEV_CHANGEMTU, dev, 9817 orig_mtu); 9818 err = notifier_to_errno(err); 9819 if (err) { 9820 /* setting mtu back and notifying everyone again, 9821 * so that they have a chance to revert changes. 9822 */ 9823 __netif_set_mtu(dev, orig_mtu); 9824 call_netdevice_notifiers_mtu(NETDEV_CHANGEMTU, dev, 9825 new_mtu); 9826 } 9827 } 9828 return err; 9829 } 9830 9831 int netif_set_mtu(struct net_device *dev, int new_mtu) 9832 { 9833 struct netlink_ext_ack extack; 9834 int err; 9835 9836 memset(&extack, 0, sizeof(extack)); 9837 err = netif_set_mtu_ext(dev, new_mtu, &extack); 9838 if (err && extack._msg) 9839 net_err_ratelimited("%s: %s\n", dev->name, extack._msg); 9840 return err; 9841 } 9842 EXPORT_SYMBOL(netif_set_mtu); 9843 9844 int netif_change_tx_queue_len(struct net_device *dev, unsigned long new_len) 9845 { 9846 unsigned int orig_len = dev->tx_queue_len; 9847 int res; 9848 9849 if (new_len != (unsigned int)new_len) 9850 return -ERANGE; 9851 9852 if (new_len != orig_len) { 9853 WRITE_ONCE(dev->tx_queue_len, new_len); 9854 res = call_netdevice_notifiers(NETDEV_CHANGE_TX_QUEUE_LEN, dev); 9855 res = notifier_to_errno(res); 9856 if (res) 9857 goto err_rollback; 9858 res = dev_qdisc_change_tx_queue_len(dev); 9859 if (res) 9860 goto err_rollback; 9861 } 9862 9863 return 0; 9864 9865 err_rollback: 9866 netdev_err(dev, "refused to change device tx_queue_len\n"); 9867 WRITE_ONCE(dev->tx_queue_len, orig_len); 9868 return res; 9869 } 9870 9871 void netif_set_group(struct net_device *dev, int new_group) 9872 { 9873 dev->group = new_group; 9874 } 9875 9876 /** 9877 * netif_pre_changeaddr_notify() - Call NETDEV_PRE_CHANGEADDR. 9878 * @dev: device 9879 * @addr: new address 9880 * @extack: netlink extended ack 9881 * 9882 * Return: 0 on success, -errno on failure. 9883 */ 9884 int netif_pre_changeaddr_notify(struct net_device *dev, const char *addr, 9885 struct netlink_ext_ack *extack) 9886 { 9887 struct netdev_notifier_pre_changeaddr_info info = { 9888 .info.dev = dev, 9889 .info.extack = extack, 9890 .dev_addr = addr, 9891 }; 9892 int rc; 9893 9894 rc = call_netdevice_notifiers_info(NETDEV_PRE_CHANGEADDR, &info.info); 9895 return notifier_to_errno(rc); 9896 } 9897 EXPORT_SYMBOL_NS_GPL(netif_pre_changeaddr_notify, "NETDEV_INTERNAL"); 9898 9899 int netif_set_mac_address(struct net_device *dev, struct sockaddr_storage *ss, 9900 struct netlink_ext_ack *extack) 9901 { 9902 const struct net_device_ops *ops = dev->netdev_ops; 9903 int err; 9904 9905 if (!ops->ndo_set_mac_address) 9906 return -EOPNOTSUPP; 9907 if (ss->ss_family != dev->type) 9908 return -EINVAL; 9909 if (!netif_device_present(dev)) 9910 return -ENODEV; 9911 err = netif_pre_changeaddr_notify(dev, ss->__data, extack); 9912 if (err) 9913 return err; 9914 if (memcmp(dev->dev_addr, ss->__data, dev->addr_len)) { 9915 err = ops->ndo_set_mac_address(dev, ss); 9916 if (err) 9917 return err; 9918 } 9919 dev->addr_assign_type = NET_ADDR_SET; 9920 call_netdevice_notifiers(NETDEV_CHANGEADDR, dev); 9921 add_device_randomness(dev->dev_addr, dev->addr_len); 9922 return 0; 9923 } 9924 9925 DECLARE_RWSEM(dev_addr_sem); 9926 9927 /* "sa" is a true struct sockaddr with limited "sa_data" member. */ 9928 int netif_get_mac_address(struct sockaddr *sa, struct net *net, char *dev_name) 9929 { 9930 size_t size = sizeof(sa->sa_data_min); 9931 struct net_device *dev; 9932 int ret = 0; 9933 9934 down_read(&dev_addr_sem); 9935 rcu_read_lock(); 9936 9937 dev = dev_get_by_name_rcu(net, dev_name); 9938 if (!dev) { 9939 ret = -ENODEV; 9940 goto unlock; 9941 } 9942 if (!dev->addr_len) 9943 memset(sa->sa_data, 0, size); 9944 else 9945 memcpy(sa->sa_data, dev->dev_addr, 9946 min_t(size_t, size, dev->addr_len)); 9947 sa->sa_family = dev->type; 9948 9949 unlock: 9950 rcu_read_unlock(); 9951 up_read(&dev_addr_sem); 9952 return ret; 9953 } 9954 EXPORT_SYMBOL_NS_GPL(netif_get_mac_address, "NETDEV_INTERNAL"); 9955 9956 int netif_change_carrier(struct net_device *dev, bool new_carrier) 9957 { 9958 const struct net_device_ops *ops = dev->netdev_ops; 9959 9960 if (!ops->ndo_change_carrier) 9961 return -EOPNOTSUPP; 9962 if (!netif_device_present(dev)) 9963 return -ENODEV; 9964 return ops->ndo_change_carrier(dev, new_carrier); 9965 } 9966 9967 /** 9968 * dev_get_phys_port_id - Get device physical port ID 9969 * @dev: device 9970 * @ppid: port ID 9971 * 9972 * Get device physical port ID 9973 */ 9974 int dev_get_phys_port_id(struct net_device *dev, 9975 struct netdev_phys_item_id *ppid) 9976 { 9977 const struct net_device_ops *ops = dev->netdev_ops; 9978 9979 if (!ops->ndo_get_phys_port_id) 9980 return -EOPNOTSUPP; 9981 return ops->ndo_get_phys_port_id(dev, ppid); 9982 } 9983 9984 /** 9985 * dev_get_phys_port_name - Get device physical port name 9986 * @dev: device 9987 * @name: port name 9988 * @len: limit of bytes to copy to name 9989 * 9990 * Get device physical port name 9991 */ 9992 int dev_get_phys_port_name(struct net_device *dev, 9993 char *name, size_t len) 9994 { 9995 const struct net_device_ops *ops = dev->netdev_ops; 9996 int err; 9997 9998 if (ops->ndo_get_phys_port_name) { 9999 err = ops->ndo_get_phys_port_name(dev, name, len); 10000 if (err != -EOPNOTSUPP) 10001 return err; 10002 } 10003 return devlink_compat_phys_port_name_get(dev, name, len); 10004 } 10005 10006 /** 10007 * netif_get_port_parent_id() - Get the device's port parent identifier 10008 * @dev: network device 10009 * @ppid: pointer to a storage for the port's parent identifier 10010 * @recurse: allow/disallow recursion to lower devices 10011 * 10012 * Get the devices's port parent identifier. 10013 * 10014 * Return: 0 on success, -errno on failure. 10015 */ 10016 int netif_get_port_parent_id(struct net_device *dev, 10017 struct netdev_phys_item_id *ppid, bool recurse) 10018 { 10019 const struct net_device_ops *ops = dev->netdev_ops; 10020 struct netdev_phys_item_id first = { }; 10021 struct net_device *lower_dev; 10022 struct list_head *iter; 10023 int err; 10024 10025 if (ops->ndo_get_port_parent_id) { 10026 err = ops->ndo_get_port_parent_id(dev, ppid); 10027 if (err != -EOPNOTSUPP) 10028 return err; 10029 } 10030 10031 err = devlink_compat_switch_id_get(dev, ppid); 10032 if (!recurse || err != -EOPNOTSUPP) 10033 return err; 10034 10035 netdev_for_each_lower_dev(dev, lower_dev, iter) { 10036 err = netif_get_port_parent_id(lower_dev, ppid, true); 10037 if (err) 10038 break; 10039 if (!first.id_len) 10040 first = *ppid; 10041 else if (memcmp(&first, ppid, sizeof(*ppid))) 10042 return -EOPNOTSUPP; 10043 } 10044 10045 return err; 10046 } 10047 EXPORT_SYMBOL(netif_get_port_parent_id); 10048 10049 /** 10050 * netdev_port_same_parent_id - Indicate if two network devices have 10051 * the same port parent identifier 10052 * @a: first network device 10053 * @b: second network device 10054 */ 10055 bool netdev_port_same_parent_id(struct net_device *a, struct net_device *b) 10056 { 10057 struct netdev_phys_item_id a_id = { }; 10058 struct netdev_phys_item_id b_id = { }; 10059 10060 if (netif_get_port_parent_id(a, &a_id, true) || 10061 netif_get_port_parent_id(b, &b_id, true)) 10062 return false; 10063 10064 return netdev_phys_item_id_same(&a_id, &b_id); 10065 } 10066 EXPORT_SYMBOL(netdev_port_same_parent_id); 10067 10068 int netif_change_proto_down(struct net_device *dev, bool proto_down) 10069 { 10070 if (!dev->change_proto_down) 10071 return -EOPNOTSUPP; 10072 if (!netif_device_present(dev)) 10073 return -ENODEV; 10074 if (proto_down) 10075 netif_carrier_off(dev); 10076 else 10077 netif_carrier_on(dev); 10078 WRITE_ONCE(dev->proto_down, proto_down); 10079 return 0; 10080 } 10081 10082 /** 10083 * netdev_change_proto_down_reason_locked - proto down reason 10084 * 10085 * @dev: device 10086 * @mask: proto down mask 10087 * @value: proto down value 10088 */ 10089 void netdev_change_proto_down_reason_locked(struct net_device *dev, 10090 unsigned long mask, u32 value) 10091 { 10092 u32 proto_down_reason; 10093 int b; 10094 10095 if (!mask) { 10096 proto_down_reason = value; 10097 } else { 10098 proto_down_reason = dev->proto_down_reason; 10099 for_each_set_bit(b, &mask, 32) { 10100 if (value & (1 << b)) 10101 proto_down_reason |= BIT(b); 10102 else 10103 proto_down_reason &= ~BIT(b); 10104 } 10105 } 10106 WRITE_ONCE(dev->proto_down_reason, proto_down_reason); 10107 } 10108 10109 struct bpf_xdp_link { 10110 struct bpf_link link; 10111 struct net_device *dev; /* protected by rtnl_lock, no refcnt held */ 10112 int flags; 10113 }; 10114 10115 static enum bpf_xdp_mode dev_xdp_mode(struct net_device *dev, u32 flags) 10116 { 10117 if (flags & XDP_FLAGS_HW_MODE) 10118 return XDP_MODE_HW; 10119 if (flags & XDP_FLAGS_DRV_MODE) 10120 return XDP_MODE_DRV; 10121 if (flags & XDP_FLAGS_SKB_MODE) 10122 return XDP_MODE_SKB; 10123 return dev->netdev_ops->ndo_bpf ? XDP_MODE_DRV : XDP_MODE_SKB; 10124 } 10125 10126 static bpf_op_t dev_xdp_bpf_op(struct net_device *dev, enum bpf_xdp_mode mode) 10127 { 10128 switch (mode) { 10129 case XDP_MODE_SKB: 10130 return generic_xdp_install; 10131 case XDP_MODE_DRV: 10132 case XDP_MODE_HW: 10133 return dev->netdev_ops->ndo_bpf; 10134 default: 10135 return NULL; 10136 } 10137 } 10138 10139 static struct bpf_xdp_link *dev_xdp_link(struct net_device *dev, 10140 enum bpf_xdp_mode mode) 10141 { 10142 return dev->xdp_state[mode].link; 10143 } 10144 10145 static struct bpf_prog *dev_xdp_prog(struct net_device *dev, 10146 enum bpf_xdp_mode mode) 10147 { 10148 struct bpf_xdp_link *link = dev_xdp_link(dev, mode); 10149 10150 if (link) 10151 return link->link.prog; 10152 return dev->xdp_state[mode].prog; 10153 } 10154 10155 u8 dev_xdp_prog_count(struct net_device *dev) 10156 { 10157 u8 count = 0; 10158 int i; 10159 10160 for (i = 0; i < __MAX_XDP_MODE; i++) 10161 if (dev->xdp_state[i].prog || dev->xdp_state[i].link) 10162 count++; 10163 return count; 10164 } 10165 EXPORT_SYMBOL_GPL(dev_xdp_prog_count); 10166 10167 u8 dev_xdp_sb_prog_count(struct net_device *dev) 10168 { 10169 u8 count = 0; 10170 int i; 10171 10172 for (i = 0; i < __MAX_XDP_MODE; i++) 10173 if (dev->xdp_state[i].prog && 10174 !dev->xdp_state[i].prog->aux->xdp_has_frags) 10175 count++; 10176 return count; 10177 } 10178 10179 int netif_xdp_propagate(struct net_device *dev, struct netdev_bpf *bpf) 10180 { 10181 if (!dev->netdev_ops->ndo_bpf) 10182 return -EOPNOTSUPP; 10183 10184 if (dev->cfg->hds_config == ETHTOOL_TCP_DATA_SPLIT_ENABLED && 10185 bpf->command == XDP_SETUP_PROG && 10186 bpf->prog && !bpf->prog->aux->xdp_has_frags) { 10187 NL_SET_ERR_MSG(bpf->extack, 10188 "unable to propagate XDP to device using tcp-data-split"); 10189 return -EBUSY; 10190 } 10191 10192 if (dev_get_min_mp_channel_count(dev)) { 10193 NL_SET_ERR_MSG(bpf->extack, "unable to propagate XDP to device using memory provider"); 10194 return -EBUSY; 10195 } 10196 10197 return dev->netdev_ops->ndo_bpf(dev, bpf); 10198 } 10199 EXPORT_SYMBOL_GPL(netif_xdp_propagate); 10200 10201 u32 dev_xdp_prog_id(struct net_device *dev, enum bpf_xdp_mode mode) 10202 { 10203 struct bpf_prog *prog = dev_xdp_prog(dev, mode); 10204 10205 return prog ? prog->aux->id : 0; 10206 } 10207 10208 static void dev_xdp_set_link(struct net_device *dev, enum bpf_xdp_mode mode, 10209 struct bpf_xdp_link *link) 10210 { 10211 dev->xdp_state[mode].link = link; 10212 dev->xdp_state[mode].prog = NULL; 10213 } 10214 10215 static void dev_xdp_set_prog(struct net_device *dev, enum bpf_xdp_mode mode, 10216 struct bpf_prog *prog) 10217 { 10218 dev->xdp_state[mode].link = NULL; 10219 dev->xdp_state[mode].prog = prog; 10220 } 10221 10222 static int dev_xdp_install(struct net_device *dev, enum bpf_xdp_mode mode, 10223 bpf_op_t bpf_op, struct netlink_ext_ack *extack, 10224 u32 flags, struct bpf_prog *prog) 10225 { 10226 struct netdev_bpf xdp; 10227 int err; 10228 10229 netdev_ops_assert_locked(dev); 10230 10231 if (dev->cfg->hds_config == ETHTOOL_TCP_DATA_SPLIT_ENABLED && 10232 prog && !prog->aux->xdp_has_frags) { 10233 NL_SET_ERR_MSG(extack, "unable to install XDP to device using tcp-data-split"); 10234 return -EBUSY; 10235 } 10236 10237 if (dev_get_min_mp_channel_count(dev)) { 10238 NL_SET_ERR_MSG(extack, "unable to install XDP to device using memory provider"); 10239 return -EBUSY; 10240 } 10241 10242 memset(&xdp, 0, sizeof(xdp)); 10243 xdp.command = mode == XDP_MODE_HW ? XDP_SETUP_PROG_HW : XDP_SETUP_PROG; 10244 xdp.extack = extack; 10245 xdp.flags = flags; 10246 xdp.prog = prog; 10247 10248 /* Drivers assume refcnt is already incremented (i.e, prog pointer is 10249 * "moved" into driver), so they don't increment it on their own, but 10250 * they do decrement refcnt when program is detached or replaced. 10251 * Given net_device also owns link/prog, we need to bump refcnt here 10252 * to prevent drivers from underflowing it. 10253 */ 10254 if (prog) 10255 bpf_prog_inc(prog); 10256 err = bpf_op(dev, &xdp); 10257 if (err) { 10258 if (prog) 10259 bpf_prog_put(prog); 10260 return err; 10261 } 10262 10263 if (mode != XDP_MODE_HW) 10264 bpf_prog_change_xdp(dev_xdp_prog(dev, mode), prog); 10265 10266 return 0; 10267 } 10268 10269 static void dev_xdp_uninstall(struct net_device *dev) 10270 { 10271 struct bpf_xdp_link *link; 10272 struct bpf_prog *prog; 10273 enum bpf_xdp_mode mode; 10274 bpf_op_t bpf_op; 10275 10276 ASSERT_RTNL(); 10277 10278 for (mode = XDP_MODE_SKB; mode < __MAX_XDP_MODE; mode++) { 10279 prog = dev_xdp_prog(dev, mode); 10280 if (!prog) 10281 continue; 10282 10283 bpf_op = dev_xdp_bpf_op(dev, mode); 10284 if (!bpf_op) 10285 continue; 10286 10287 WARN_ON(dev_xdp_install(dev, mode, bpf_op, NULL, 0, NULL)); 10288 10289 /* auto-detach link from net device */ 10290 link = dev_xdp_link(dev, mode); 10291 if (link) 10292 link->dev = NULL; 10293 else 10294 bpf_prog_put(prog); 10295 10296 dev_xdp_set_link(dev, mode, NULL); 10297 } 10298 } 10299 10300 static int dev_xdp_attach(struct net_device *dev, struct netlink_ext_ack *extack, 10301 struct bpf_xdp_link *link, struct bpf_prog *new_prog, 10302 struct bpf_prog *old_prog, u32 flags) 10303 { 10304 unsigned int num_modes = hweight32(flags & XDP_FLAGS_MODES); 10305 struct bpf_prog *cur_prog; 10306 struct net_device *upper; 10307 struct list_head *iter; 10308 enum bpf_xdp_mode mode; 10309 bpf_op_t bpf_op; 10310 int err; 10311 10312 ASSERT_RTNL(); 10313 10314 /* either link or prog attachment, never both */ 10315 if (link && (new_prog || old_prog)) 10316 return -EINVAL; 10317 /* link supports only XDP mode flags */ 10318 if (link && (flags & ~XDP_FLAGS_MODES)) { 10319 NL_SET_ERR_MSG(extack, "Invalid XDP flags for BPF link attachment"); 10320 return -EINVAL; 10321 } 10322 /* just one XDP mode bit should be set, zero defaults to drv/skb mode */ 10323 if (num_modes > 1) { 10324 NL_SET_ERR_MSG(extack, "Only one XDP mode flag can be set"); 10325 return -EINVAL; 10326 } 10327 /* avoid ambiguity if offload + drv/skb mode progs are both loaded */ 10328 if (!num_modes && dev_xdp_prog_count(dev) > 1) { 10329 NL_SET_ERR_MSG(extack, 10330 "More than one program loaded, unset mode is ambiguous"); 10331 return -EINVAL; 10332 } 10333 /* old_prog != NULL implies XDP_FLAGS_REPLACE is set */ 10334 if (old_prog && !(flags & XDP_FLAGS_REPLACE)) { 10335 NL_SET_ERR_MSG(extack, "XDP_FLAGS_REPLACE is not specified"); 10336 return -EINVAL; 10337 } 10338 10339 mode = dev_xdp_mode(dev, flags); 10340 /* can't replace attached link */ 10341 if (dev_xdp_link(dev, mode)) { 10342 NL_SET_ERR_MSG(extack, "Can't replace active BPF XDP link"); 10343 return -EBUSY; 10344 } 10345 10346 /* don't allow if an upper device already has a program */ 10347 netdev_for_each_upper_dev_rcu(dev, upper, iter) { 10348 if (dev_xdp_prog_count(upper) > 0) { 10349 NL_SET_ERR_MSG(extack, "Cannot attach when an upper device already has a program"); 10350 return -EEXIST; 10351 } 10352 } 10353 10354 cur_prog = dev_xdp_prog(dev, mode); 10355 /* can't replace attached prog with link */ 10356 if (link && cur_prog) { 10357 NL_SET_ERR_MSG(extack, "Can't replace active XDP program with BPF link"); 10358 return -EBUSY; 10359 } 10360 if ((flags & XDP_FLAGS_REPLACE) && cur_prog != old_prog) { 10361 NL_SET_ERR_MSG(extack, "Active program does not match expected"); 10362 return -EEXIST; 10363 } 10364 10365 /* put effective new program into new_prog */ 10366 if (link) 10367 new_prog = link->link.prog; 10368 10369 if (new_prog) { 10370 bool offload = mode == XDP_MODE_HW; 10371 enum bpf_xdp_mode other_mode = mode == XDP_MODE_SKB 10372 ? XDP_MODE_DRV : XDP_MODE_SKB; 10373 10374 if ((flags & XDP_FLAGS_UPDATE_IF_NOEXIST) && cur_prog) { 10375 NL_SET_ERR_MSG(extack, "XDP program already attached"); 10376 return -EBUSY; 10377 } 10378 if (!offload && dev_xdp_prog(dev, other_mode)) { 10379 NL_SET_ERR_MSG(extack, "Native and generic XDP can't be active at the same time"); 10380 return -EEXIST; 10381 } 10382 if (!offload && bpf_prog_is_offloaded(new_prog->aux)) { 10383 NL_SET_ERR_MSG(extack, "Using offloaded program without HW_MODE flag is not supported"); 10384 return -EINVAL; 10385 } 10386 if (bpf_prog_is_dev_bound(new_prog->aux) && !bpf_offload_dev_match(new_prog, dev)) { 10387 NL_SET_ERR_MSG(extack, "Program bound to different device"); 10388 return -EINVAL; 10389 } 10390 if (bpf_prog_is_dev_bound(new_prog->aux) && mode == XDP_MODE_SKB) { 10391 NL_SET_ERR_MSG(extack, "Can't attach device-bound programs in generic mode"); 10392 return -EINVAL; 10393 } 10394 if (new_prog->expected_attach_type == BPF_XDP_DEVMAP) { 10395 NL_SET_ERR_MSG(extack, "BPF_XDP_DEVMAP programs can not be attached to a device"); 10396 return -EINVAL; 10397 } 10398 if (new_prog->expected_attach_type == BPF_XDP_CPUMAP) { 10399 NL_SET_ERR_MSG(extack, "BPF_XDP_CPUMAP programs can not be attached to a device"); 10400 return -EINVAL; 10401 } 10402 } 10403 10404 /* don't call drivers if the effective program didn't change */ 10405 if (new_prog != cur_prog) { 10406 bpf_op = dev_xdp_bpf_op(dev, mode); 10407 if (!bpf_op) { 10408 NL_SET_ERR_MSG(extack, "Underlying driver does not support XDP in native mode"); 10409 return -EOPNOTSUPP; 10410 } 10411 10412 err = dev_xdp_install(dev, mode, bpf_op, extack, flags, new_prog); 10413 if (err) 10414 return err; 10415 } 10416 10417 if (link) 10418 dev_xdp_set_link(dev, mode, link); 10419 else 10420 dev_xdp_set_prog(dev, mode, new_prog); 10421 if (cur_prog) 10422 bpf_prog_put(cur_prog); 10423 10424 return 0; 10425 } 10426 10427 static int dev_xdp_attach_link(struct net_device *dev, 10428 struct netlink_ext_ack *extack, 10429 struct bpf_xdp_link *link) 10430 { 10431 return dev_xdp_attach(dev, extack, link, NULL, NULL, link->flags); 10432 } 10433 10434 static int dev_xdp_detach_link(struct net_device *dev, 10435 struct netlink_ext_ack *extack, 10436 struct bpf_xdp_link *link) 10437 { 10438 enum bpf_xdp_mode mode; 10439 bpf_op_t bpf_op; 10440 10441 ASSERT_RTNL(); 10442 10443 mode = dev_xdp_mode(dev, link->flags); 10444 if (dev_xdp_link(dev, mode) != link) 10445 return -EINVAL; 10446 10447 bpf_op = dev_xdp_bpf_op(dev, mode); 10448 WARN_ON(dev_xdp_install(dev, mode, bpf_op, NULL, 0, NULL)); 10449 dev_xdp_set_link(dev, mode, NULL); 10450 return 0; 10451 } 10452 10453 static void bpf_xdp_link_release(struct bpf_link *link) 10454 { 10455 struct bpf_xdp_link *xdp_link = container_of(link, struct bpf_xdp_link, link); 10456 10457 rtnl_lock(); 10458 10459 /* if racing with net_device's tear down, xdp_link->dev might be 10460 * already NULL, in which case link was already auto-detached 10461 */ 10462 if (xdp_link->dev) { 10463 netdev_lock_ops(xdp_link->dev); 10464 WARN_ON(dev_xdp_detach_link(xdp_link->dev, NULL, xdp_link)); 10465 netdev_unlock_ops(xdp_link->dev); 10466 xdp_link->dev = NULL; 10467 } 10468 10469 rtnl_unlock(); 10470 } 10471 10472 static int bpf_xdp_link_detach(struct bpf_link *link) 10473 { 10474 bpf_xdp_link_release(link); 10475 return 0; 10476 } 10477 10478 static void bpf_xdp_link_dealloc(struct bpf_link *link) 10479 { 10480 struct bpf_xdp_link *xdp_link = container_of(link, struct bpf_xdp_link, link); 10481 10482 kfree(xdp_link); 10483 } 10484 10485 static void bpf_xdp_link_show_fdinfo(const struct bpf_link *link, 10486 struct seq_file *seq) 10487 { 10488 struct bpf_xdp_link *xdp_link = container_of(link, struct bpf_xdp_link, link); 10489 u32 ifindex = 0; 10490 10491 rtnl_lock(); 10492 if (xdp_link->dev) 10493 ifindex = xdp_link->dev->ifindex; 10494 rtnl_unlock(); 10495 10496 seq_printf(seq, "ifindex:\t%u\n", ifindex); 10497 } 10498 10499 static int bpf_xdp_link_fill_link_info(const struct bpf_link *link, 10500 struct bpf_link_info *info) 10501 { 10502 struct bpf_xdp_link *xdp_link = container_of(link, struct bpf_xdp_link, link); 10503 u32 ifindex = 0; 10504 10505 rtnl_lock(); 10506 if (xdp_link->dev) 10507 ifindex = xdp_link->dev->ifindex; 10508 rtnl_unlock(); 10509 10510 info->xdp.ifindex = ifindex; 10511 return 0; 10512 } 10513 10514 static int bpf_xdp_link_update(struct bpf_link *link, struct bpf_prog *new_prog, 10515 struct bpf_prog *old_prog) 10516 { 10517 struct bpf_xdp_link *xdp_link = container_of(link, struct bpf_xdp_link, link); 10518 enum bpf_xdp_mode mode; 10519 bpf_op_t bpf_op; 10520 int err = 0; 10521 10522 rtnl_lock(); 10523 10524 /* link might have been auto-released already, so fail */ 10525 if (!xdp_link->dev) { 10526 err = -ENOLINK; 10527 goto out_unlock; 10528 } 10529 10530 if (old_prog && link->prog != old_prog) { 10531 err = -EPERM; 10532 goto out_unlock; 10533 } 10534 old_prog = link->prog; 10535 if (old_prog->type != new_prog->type || 10536 old_prog->expected_attach_type != new_prog->expected_attach_type) { 10537 err = -EINVAL; 10538 goto out_unlock; 10539 } 10540 10541 if (old_prog == new_prog) { 10542 /* no-op, don't disturb drivers */ 10543 bpf_prog_put(new_prog); 10544 goto out_unlock; 10545 } 10546 10547 netdev_lock_ops(xdp_link->dev); 10548 mode = dev_xdp_mode(xdp_link->dev, xdp_link->flags); 10549 bpf_op = dev_xdp_bpf_op(xdp_link->dev, mode); 10550 err = dev_xdp_install(xdp_link->dev, mode, bpf_op, NULL, 10551 xdp_link->flags, new_prog); 10552 netdev_unlock_ops(xdp_link->dev); 10553 if (err) 10554 goto out_unlock; 10555 10556 old_prog = xchg(&link->prog, new_prog); 10557 bpf_prog_put(old_prog); 10558 10559 out_unlock: 10560 rtnl_unlock(); 10561 return err; 10562 } 10563 10564 static const struct bpf_link_ops bpf_xdp_link_lops = { 10565 .release = bpf_xdp_link_release, 10566 .dealloc = bpf_xdp_link_dealloc, 10567 .detach = bpf_xdp_link_detach, 10568 .show_fdinfo = bpf_xdp_link_show_fdinfo, 10569 .fill_link_info = bpf_xdp_link_fill_link_info, 10570 .update_prog = bpf_xdp_link_update, 10571 }; 10572 10573 int bpf_xdp_link_attach(const union bpf_attr *attr, struct bpf_prog *prog) 10574 { 10575 struct net *net = current->nsproxy->net_ns; 10576 struct bpf_link_primer link_primer; 10577 struct netlink_ext_ack extack = {}; 10578 struct bpf_xdp_link *link; 10579 struct net_device *dev; 10580 int err, fd; 10581 10582 rtnl_lock(); 10583 dev = dev_get_by_index(net, attr->link_create.target_ifindex); 10584 if (!dev) { 10585 rtnl_unlock(); 10586 return -EINVAL; 10587 } 10588 10589 link = kzalloc(sizeof(*link), GFP_USER); 10590 if (!link) { 10591 err = -ENOMEM; 10592 goto unlock; 10593 } 10594 10595 bpf_link_init(&link->link, BPF_LINK_TYPE_XDP, &bpf_xdp_link_lops, prog, 10596 attr->link_create.attach_type); 10597 link->dev = dev; 10598 link->flags = attr->link_create.flags; 10599 10600 err = bpf_link_prime(&link->link, &link_primer); 10601 if (err) { 10602 kfree(link); 10603 goto unlock; 10604 } 10605 10606 netdev_lock_ops(dev); 10607 err = dev_xdp_attach_link(dev, &extack, link); 10608 netdev_unlock_ops(dev); 10609 rtnl_unlock(); 10610 10611 if (err) { 10612 link->dev = NULL; 10613 bpf_link_cleanup(&link_primer); 10614 trace_bpf_xdp_link_attach_failed(extack._msg); 10615 goto out_put_dev; 10616 } 10617 10618 fd = bpf_link_settle(&link_primer); 10619 /* link itself doesn't hold dev's refcnt to not complicate shutdown */ 10620 dev_put(dev); 10621 return fd; 10622 10623 unlock: 10624 rtnl_unlock(); 10625 10626 out_put_dev: 10627 dev_put(dev); 10628 return err; 10629 } 10630 10631 /** 10632 * dev_change_xdp_fd - set or clear a bpf program for a device rx path 10633 * @dev: device 10634 * @extack: netlink extended ack 10635 * @fd: new program fd or negative value to clear 10636 * @expected_fd: old program fd that userspace expects to replace or clear 10637 * @flags: xdp-related flags 10638 * 10639 * Set or clear a bpf program for a device 10640 */ 10641 int dev_change_xdp_fd(struct net_device *dev, struct netlink_ext_ack *extack, 10642 int fd, int expected_fd, u32 flags) 10643 { 10644 enum bpf_xdp_mode mode = dev_xdp_mode(dev, flags); 10645 struct bpf_prog *new_prog = NULL, *old_prog = NULL; 10646 int err; 10647 10648 ASSERT_RTNL(); 10649 10650 if (fd >= 0) { 10651 new_prog = bpf_prog_get_type_dev(fd, BPF_PROG_TYPE_XDP, 10652 mode != XDP_MODE_SKB); 10653 if (IS_ERR(new_prog)) 10654 return PTR_ERR(new_prog); 10655 } 10656 10657 if (expected_fd >= 0) { 10658 old_prog = bpf_prog_get_type_dev(expected_fd, BPF_PROG_TYPE_XDP, 10659 mode != XDP_MODE_SKB); 10660 if (IS_ERR(old_prog)) { 10661 err = PTR_ERR(old_prog); 10662 old_prog = NULL; 10663 goto err_out; 10664 } 10665 } 10666 10667 err = dev_xdp_attach(dev, extack, NULL, new_prog, old_prog, flags); 10668 10669 err_out: 10670 if (err && new_prog) 10671 bpf_prog_put(new_prog); 10672 if (old_prog) 10673 bpf_prog_put(old_prog); 10674 return err; 10675 } 10676 10677 u32 dev_get_min_mp_channel_count(const struct net_device *dev) 10678 { 10679 int i; 10680 10681 netdev_ops_assert_locked(dev); 10682 10683 for (i = dev->real_num_rx_queues - 1; i >= 0; i--) 10684 if (dev->_rx[i].mp_params.mp_priv) 10685 /* The channel count is the idx plus 1. */ 10686 return i + 1; 10687 10688 return 0; 10689 } 10690 10691 /** 10692 * dev_index_reserve() - allocate an ifindex in a namespace 10693 * @net: the applicable net namespace 10694 * @ifindex: requested ifindex, pass %0 to get one allocated 10695 * 10696 * Allocate a ifindex for a new device. Caller must either use the ifindex 10697 * to store the device (via list_netdevice()) or call dev_index_release() 10698 * to give the index up. 10699 * 10700 * Return: a suitable unique value for a new device interface number or -errno. 10701 */ 10702 static int dev_index_reserve(struct net *net, u32 ifindex) 10703 { 10704 int err; 10705 10706 if (ifindex > INT_MAX) { 10707 DEBUG_NET_WARN_ON_ONCE(1); 10708 return -EINVAL; 10709 } 10710 10711 if (!ifindex) 10712 err = xa_alloc_cyclic(&net->dev_by_index, &ifindex, NULL, 10713 xa_limit_31b, &net->ifindex, GFP_KERNEL); 10714 else 10715 err = xa_insert(&net->dev_by_index, ifindex, NULL, GFP_KERNEL); 10716 if (err < 0) 10717 return err; 10718 10719 return ifindex; 10720 } 10721 10722 static void dev_index_release(struct net *net, int ifindex) 10723 { 10724 /* Expect only unused indexes, unlist_netdevice() removes the used */ 10725 WARN_ON(xa_erase(&net->dev_by_index, ifindex)); 10726 } 10727 10728 static bool from_cleanup_net(void) 10729 { 10730 #ifdef CONFIG_NET_NS 10731 return current == READ_ONCE(cleanup_net_task); 10732 #else 10733 return false; 10734 #endif 10735 } 10736 10737 /* Delayed registration/unregisteration */ 10738 LIST_HEAD(net_todo_list); 10739 DECLARE_WAIT_QUEUE_HEAD(netdev_unregistering_wq); 10740 atomic_t dev_unreg_count = ATOMIC_INIT(0); 10741 10742 static void net_set_todo(struct net_device *dev) 10743 { 10744 list_add_tail(&dev->todo_list, &net_todo_list); 10745 } 10746 10747 static netdev_features_t netdev_sync_upper_features(struct net_device *lower, 10748 struct net_device *upper, netdev_features_t features) 10749 { 10750 netdev_features_t upper_disables = NETIF_F_UPPER_DISABLES; 10751 netdev_features_t feature; 10752 int feature_bit; 10753 10754 for_each_netdev_feature(upper_disables, feature_bit) { 10755 feature = __NETIF_F_BIT(feature_bit); 10756 if (!(upper->wanted_features & feature) 10757 && (features & feature)) { 10758 netdev_dbg(lower, "Dropping feature %pNF, upper dev %s has it off.\n", 10759 &feature, upper->name); 10760 features &= ~feature; 10761 } 10762 } 10763 10764 return features; 10765 } 10766 10767 static void netdev_sync_lower_features(struct net_device *upper, 10768 struct net_device *lower, netdev_features_t features) 10769 { 10770 netdev_features_t upper_disables = NETIF_F_UPPER_DISABLES; 10771 netdev_features_t feature; 10772 int feature_bit; 10773 10774 for_each_netdev_feature(upper_disables, feature_bit) { 10775 feature = __NETIF_F_BIT(feature_bit); 10776 if (!(features & feature) && (lower->features & feature)) { 10777 netdev_dbg(upper, "Disabling feature %pNF on lower dev %s.\n", 10778 &feature, lower->name); 10779 netdev_lock_ops(lower); 10780 lower->wanted_features &= ~feature; 10781 __netdev_update_features(lower); 10782 10783 if (unlikely(lower->features & feature)) 10784 netdev_WARN(upper, "failed to disable %pNF on %s!\n", 10785 &feature, lower->name); 10786 else 10787 netdev_features_change(lower); 10788 netdev_unlock_ops(lower); 10789 } 10790 } 10791 } 10792 10793 static bool netdev_has_ip_or_hw_csum(netdev_features_t features) 10794 { 10795 netdev_features_t ip_csum_mask = NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM; 10796 bool ip_csum = (features & ip_csum_mask) == ip_csum_mask; 10797 bool hw_csum = features & NETIF_F_HW_CSUM; 10798 10799 return ip_csum || hw_csum; 10800 } 10801 10802 static netdev_features_t netdev_fix_features(struct net_device *dev, 10803 netdev_features_t features) 10804 { 10805 /* Fix illegal checksum combinations */ 10806 if ((features & NETIF_F_HW_CSUM) && 10807 (features & (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))) { 10808 netdev_warn(dev, "mixed HW and IP checksum settings.\n"); 10809 features &= ~(NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM); 10810 } 10811 10812 /* TSO requires that SG is present as well. */ 10813 if ((features & NETIF_F_ALL_TSO) && !(features & NETIF_F_SG)) { 10814 netdev_dbg(dev, "Dropping TSO features since no SG feature.\n"); 10815 features &= ~NETIF_F_ALL_TSO; 10816 } 10817 10818 if ((features & NETIF_F_TSO) && !(features & NETIF_F_HW_CSUM) && 10819 !(features & NETIF_F_IP_CSUM)) { 10820 netdev_dbg(dev, "Dropping TSO features since no CSUM feature.\n"); 10821 features &= ~NETIF_F_TSO; 10822 features &= ~NETIF_F_TSO_ECN; 10823 } 10824 10825 if ((features & NETIF_F_TSO6) && !(features & NETIF_F_HW_CSUM) && 10826 !(features & NETIF_F_IPV6_CSUM)) { 10827 netdev_dbg(dev, "Dropping TSO6 features since no CSUM feature.\n"); 10828 features &= ~NETIF_F_TSO6; 10829 } 10830 10831 /* TSO with IPv4 ID mangling requires IPv4 TSO be enabled */ 10832 if ((features & NETIF_F_TSO_MANGLEID) && !(features & NETIF_F_TSO)) 10833 features &= ~NETIF_F_TSO_MANGLEID; 10834 10835 /* TSO ECN requires that TSO is present as well. */ 10836 if ((features & NETIF_F_ALL_TSO) == NETIF_F_TSO_ECN) 10837 features &= ~NETIF_F_TSO_ECN; 10838 10839 /* Software GSO depends on SG. */ 10840 if ((features & NETIF_F_GSO) && !(features & NETIF_F_SG)) { 10841 netdev_dbg(dev, "Dropping NETIF_F_GSO since no SG feature.\n"); 10842 features &= ~NETIF_F_GSO; 10843 } 10844 10845 /* GSO partial features require GSO partial be set */ 10846 if ((features & dev->gso_partial_features) && 10847 !(features & NETIF_F_GSO_PARTIAL)) { 10848 netdev_dbg(dev, 10849 "Dropping partially supported GSO features since no GSO partial.\n"); 10850 features &= ~dev->gso_partial_features; 10851 } 10852 10853 if (!(features & NETIF_F_RXCSUM)) { 10854 /* NETIF_F_GRO_HW implies doing RXCSUM since every packet 10855 * successfully merged by hardware must also have the 10856 * checksum verified by hardware. If the user does not 10857 * want to enable RXCSUM, logically, we should disable GRO_HW. 10858 */ 10859 if (features & NETIF_F_GRO_HW) { 10860 netdev_dbg(dev, "Dropping NETIF_F_GRO_HW since no RXCSUM feature.\n"); 10861 features &= ~NETIF_F_GRO_HW; 10862 } 10863 } 10864 10865 /* LRO/HW-GRO features cannot be combined with RX-FCS */ 10866 if (features & NETIF_F_RXFCS) { 10867 if (features & NETIF_F_LRO) { 10868 netdev_dbg(dev, "Dropping LRO feature since RX-FCS is requested.\n"); 10869 features &= ~NETIF_F_LRO; 10870 } 10871 10872 if (features & NETIF_F_GRO_HW) { 10873 netdev_dbg(dev, "Dropping HW-GRO feature since RX-FCS is requested.\n"); 10874 features &= ~NETIF_F_GRO_HW; 10875 } 10876 } 10877 10878 if ((features & NETIF_F_GRO_HW) && (features & NETIF_F_LRO)) { 10879 netdev_dbg(dev, "Dropping LRO feature since HW-GRO is requested.\n"); 10880 features &= ~NETIF_F_LRO; 10881 } 10882 10883 if ((features & NETIF_F_HW_TLS_TX) && !netdev_has_ip_or_hw_csum(features)) { 10884 netdev_dbg(dev, "Dropping TLS TX HW offload feature since no CSUM feature.\n"); 10885 features &= ~NETIF_F_HW_TLS_TX; 10886 } 10887 10888 if ((features & NETIF_F_HW_TLS_RX) && !(features & NETIF_F_RXCSUM)) { 10889 netdev_dbg(dev, "Dropping TLS RX HW offload feature since no RXCSUM feature.\n"); 10890 features &= ~NETIF_F_HW_TLS_RX; 10891 } 10892 10893 if ((features & NETIF_F_GSO_UDP_L4) && !netdev_has_ip_or_hw_csum(features)) { 10894 netdev_dbg(dev, "Dropping USO feature since no CSUM feature.\n"); 10895 features &= ~NETIF_F_GSO_UDP_L4; 10896 } 10897 10898 return features; 10899 } 10900 10901 int __netdev_update_features(struct net_device *dev) 10902 { 10903 struct net_device *upper, *lower; 10904 netdev_features_t features; 10905 struct list_head *iter; 10906 int err = -1; 10907 10908 ASSERT_RTNL(); 10909 netdev_ops_assert_locked(dev); 10910 10911 features = netdev_get_wanted_features(dev); 10912 10913 if (dev->netdev_ops->ndo_fix_features) 10914 features = dev->netdev_ops->ndo_fix_features(dev, features); 10915 10916 /* driver might be less strict about feature dependencies */ 10917 features = netdev_fix_features(dev, features); 10918 10919 /* some features can't be enabled if they're off on an upper device */ 10920 netdev_for_each_upper_dev_rcu(dev, upper, iter) 10921 features = netdev_sync_upper_features(dev, upper, features); 10922 10923 if (dev->features == features) 10924 goto sync_lower; 10925 10926 netdev_dbg(dev, "Features changed: %pNF -> %pNF\n", 10927 &dev->features, &features); 10928 10929 if (dev->netdev_ops->ndo_set_features) 10930 err = dev->netdev_ops->ndo_set_features(dev, features); 10931 else 10932 err = 0; 10933 10934 if (unlikely(err < 0)) { 10935 netdev_err(dev, 10936 "set_features() failed (%d); wanted %pNF, left %pNF\n", 10937 err, &features, &dev->features); 10938 /* return non-0 since some features might have changed and 10939 * it's better to fire a spurious notification than miss it 10940 */ 10941 return -1; 10942 } 10943 10944 sync_lower: 10945 /* some features must be disabled on lower devices when disabled 10946 * on an upper device (think: bonding master or bridge) 10947 */ 10948 netdev_for_each_lower_dev(dev, lower, iter) 10949 netdev_sync_lower_features(dev, lower, features); 10950 10951 if (!err) { 10952 netdev_features_t diff = features ^ dev->features; 10953 10954 if (diff & NETIF_F_RX_UDP_TUNNEL_PORT) { 10955 /* udp_tunnel_{get,drop}_rx_info both need 10956 * NETIF_F_RX_UDP_TUNNEL_PORT enabled on the 10957 * device, or they won't do anything. 10958 * Thus we need to update dev->features 10959 * *before* calling udp_tunnel_get_rx_info, 10960 * but *after* calling udp_tunnel_drop_rx_info. 10961 */ 10962 udp_tunnel_nic_lock(dev); 10963 if (features & NETIF_F_RX_UDP_TUNNEL_PORT) { 10964 dev->features = features; 10965 udp_tunnel_get_rx_info(dev); 10966 } else { 10967 udp_tunnel_drop_rx_info(dev); 10968 } 10969 udp_tunnel_nic_unlock(dev); 10970 } 10971 10972 if (diff & NETIF_F_HW_VLAN_CTAG_FILTER) { 10973 if (features & NETIF_F_HW_VLAN_CTAG_FILTER) { 10974 dev->features = features; 10975 err |= vlan_get_rx_ctag_filter_info(dev); 10976 } else { 10977 vlan_drop_rx_ctag_filter_info(dev); 10978 } 10979 } 10980 10981 if (diff & NETIF_F_HW_VLAN_STAG_FILTER) { 10982 if (features & NETIF_F_HW_VLAN_STAG_FILTER) { 10983 dev->features = features; 10984 err |= vlan_get_rx_stag_filter_info(dev); 10985 } else { 10986 vlan_drop_rx_stag_filter_info(dev); 10987 } 10988 } 10989 10990 dev->features = features; 10991 } 10992 10993 return err < 0 ? 0 : 1; 10994 } 10995 10996 /** 10997 * netdev_update_features - recalculate device features 10998 * @dev: the device to check 10999 * 11000 * Recalculate dev->features set and send notifications if it 11001 * has changed. Should be called after driver or hardware dependent 11002 * conditions might have changed that influence the features. 11003 */ 11004 void netdev_update_features(struct net_device *dev) 11005 { 11006 if (__netdev_update_features(dev)) 11007 netdev_features_change(dev); 11008 } 11009 EXPORT_SYMBOL(netdev_update_features); 11010 11011 /** 11012 * netdev_change_features - recalculate device features 11013 * @dev: the device to check 11014 * 11015 * Recalculate dev->features set and send notifications even 11016 * if they have not changed. Should be called instead of 11017 * netdev_update_features() if also dev->vlan_features might 11018 * have changed to allow the changes to be propagated to stacked 11019 * VLAN devices. 11020 */ 11021 void netdev_change_features(struct net_device *dev) 11022 { 11023 __netdev_update_features(dev); 11024 netdev_features_change(dev); 11025 } 11026 EXPORT_SYMBOL(netdev_change_features); 11027 11028 /** 11029 * netif_stacked_transfer_operstate - transfer operstate 11030 * @rootdev: the root or lower level device to transfer state from 11031 * @dev: the device to transfer operstate to 11032 * 11033 * Transfer operational state from root to device. This is normally 11034 * called when a stacking relationship exists between the root 11035 * device and the device(a leaf device). 11036 */ 11037 void netif_stacked_transfer_operstate(const struct net_device *rootdev, 11038 struct net_device *dev) 11039 { 11040 if (rootdev->operstate == IF_OPER_DORMANT) 11041 netif_dormant_on(dev); 11042 else 11043 netif_dormant_off(dev); 11044 11045 if (rootdev->operstate == IF_OPER_TESTING) 11046 netif_testing_on(dev); 11047 else 11048 netif_testing_off(dev); 11049 11050 if (netif_carrier_ok(rootdev)) 11051 netif_carrier_on(dev); 11052 else 11053 netif_carrier_off(dev); 11054 } 11055 EXPORT_SYMBOL(netif_stacked_transfer_operstate); 11056 11057 static int netif_alloc_rx_queues(struct net_device *dev) 11058 { 11059 unsigned int i, count = dev->num_rx_queues; 11060 struct netdev_rx_queue *rx; 11061 size_t sz = count * sizeof(*rx); 11062 int err = 0; 11063 11064 BUG_ON(count < 1); 11065 11066 rx = kvzalloc(sz, GFP_KERNEL_ACCOUNT | __GFP_RETRY_MAYFAIL); 11067 if (!rx) 11068 return -ENOMEM; 11069 11070 dev->_rx = rx; 11071 11072 for (i = 0; i < count; i++) { 11073 rx[i].dev = dev; 11074 11075 /* XDP RX-queue setup */ 11076 err = xdp_rxq_info_reg(&rx[i].xdp_rxq, dev, i, 0); 11077 if (err < 0) 11078 goto err_rxq_info; 11079 } 11080 return 0; 11081 11082 err_rxq_info: 11083 /* Rollback successful reg's and free other resources */ 11084 while (i--) 11085 xdp_rxq_info_unreg(&rx[i].xdp_rxq); 11086 kvfree(dev->_rx); 11087 dev->_rx = NULL; 11088 return err; 11089 } 11090 11091 static void netif_free_rx_queues(struct net_device *dev) 11092 { 11093 unsigned int i, count = dev->num_rx_queues; 11094 11095 /* netif_alloc_rx_queues alloc failed, resources have been unreg'ed */ 11096 if (!dev->_rx) 11097 return; 11098 11099 for (i = 0; i < count; i++) 11100 xdp_rxq_info_unreg(&dev->_rx[i].xdp_rxq); 11101 11102 kvfree(dev->_rx); 11103 } 11104 11105 static void netdev_init_one_queue(struct net_device *dev, 11106 struct netdev_queue *queue, void *_unused) 11107 { 11108 /* Initialize queue lock */ 11109 spin_lock_init(&queue->_xmit_lock); 11110 netdev_set_xmit_lockdep_class(&queue->_xmit_lock, dev->type); 11111 queue->xmit_lock_owner = -1; 11112 netdev_queue_numa_node_write(queue, NUMA_NO_NODE); 11113 queue->dev = dev; 11114 #ifdef CONFIG_BQL 11115 dql_init(&queue->dql, HZ); 11116 #endif 11117 } 11118 11119 static void netif_free_tx_queues(struct net_device *dev) 11120 { 11121 kvfree(dev->_tx); 11122 } 11123 11124 static int netif_alloc_netdev_queues(struct net_device *dev) 11125 { 11126 unsigned int count = dev->num_tx_queues; 11127 struct netdev_queue *tx; 11128 size_t sz = count * sizeof(*tx); 11129 11130 if (count < 1 || count > 0xffff) 11131 return -EINVAL; 11132 11133 tx = kvzalloc(sz, GFP_KERNEL_ACCOUNT | __GFP_RETRY_MAYFAIL); 11134 if (!tx) 11135 return -ENOMEM; 11136 11137 dev->_tx = tx; 11138 11139 netdev_for_each_tx_queue(dev, netdev_init_one_queue, NULL); 11140 spin_lock_init(&dev->tx_global_lock); 11141 11142 return 0; 11143 } 11144 11145 void netif_tx_stop_all_queues(struct net_device *dev) 11146 { 11147 unsigned int i; 11148 11149 for (i = 0; i < dev->num_tx_queues; i++) { 11150 struct netdev_queue *txq = netdev_get_tx_queue(dev, i); 11151 11152 netif_tx_stop_queue(txq); 11153 } 11154 } 11155 EXPORT_SYMBOL(netif_tx_stop_all_queues); 11156 11157 static int netdev_do_alloc_pcpu_stats(struct net_device *dev) 11158 { 11159 void __percpu *v; 11160 11161 /* Drivers implementing ndo_get_peer_dev must support tstat 11162 * accounting, so that skb_do_redirect() can bump the dev's 11163 * RX stats upon network namespace switch. 11164 */ 11165 if (dev->netdev_ops->ndo_get_peer_dev && 11166 dev->pcpu_stat_type != NETDEV_PCPU_STAT_TSTATS) 11167 return -EOPNOTSUPP; 11168 11169 switch (dev->pcpu_stat_type) { 11170 case NETDEV_PCPU_STAT_NONE: 11171 return 0; 11172 case NETDEV_PCPU_STAT_LSTATS: 11173 v = dev->lstats = netdev_alloc_pcpu_stats(struct pcpu_lstats); 11174 break; 11175 case NETDEV_PCPU_STAT_TSTATS: 11176 v = dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats); 11177 break; 11178 case NETDEV_PCPU_STAT_DSTATS: 11179 v = dev->dstats = netdev_alloc_pcpu_stats(struct pcpu_dstats); 11180 break; 11181 default: 11182 return -EINVAL; 11183 } 11184 11185 return v ? 0 : -ENOMEM; 11186 } 11187 11188 static void netdev_do_free_pcpu_stats(struct net_device *dev) 11189 { 11190 switch (dev->pcpu_stat_type) { 11191 case NETDEV_PCPU_STAT_NONE: 11192 return; 11193 case NETDEV_PCPU_STAT_LSTATS: 11194 free_percpu(dev->lstats); 11195 break; 11196 case NETDEV_PCPU_STAT_TSTATS: 11197 free_percpu(dev->tstats); 11198 break; 11199 case NETDEV_PCPU_STAT_DSTATS: 11200 free_percpu(dev->dstats); 11201 break; 11202 } 11203 } 11204 11205 static void netdev_free_phy_link_topology(struct net_device *dev) 11206 { 11207 struct phy_link_topology *topo = dev->link_topo; 11208 11209 if (IS_ENABLED(CONFIG_PHYLIB) && topo) { 11210 xa_destroy(&topo->phys); 11211 kfree(topo); 11212 dev->link_topo = NULL; 11213 } 11214 } 11215 11216 /** 11217 * register_netdevice() - register a network device 11218 * @dev: device to register 11219 * 11220 * Take a prepared network device structure and make it externally accessible. 11221 * A %NETDEV_REGISTER message is sent to the netdev notifier chain. 11222 * Callers must hold the rtnl lock - you may want register_netdev() 11223 * instead of this. 11224 */ 11225 int register_netdevice(struct net_device *dev) 11226 { 11227 int ret; 11228 struct net *net = dev_net(dev); 11229 11230 BUILD_BUG_ON(sizeof(netdev_features_t) * BITS_PER_BYTE < 11231 NETDEV_FEATURE_COUNT); 11232 BUG_ON(dev_boot_phase); 11233 ASSERT_RTNL(); 11234 11235 might_sleep(); 11236 11237 /* When net_device's are persistent, this will be fatal. */ 11238 BUG_ON(dev->reg_state != NETREG_UNINITIALIZED); 11239 BUG_ON(!net); 11240 11241 ret = ethtool_check_ops(dev->ethtool_ops); 11242 if (ret) 11243 return ret; 11244 11245 /* rss ctx ID 0 is reserved for the default context, start from 1 */ 11246 xa_init_flags(&dev->ethtool->rss_ctx, XA_FLAGS_ALLOC1); 11247 mutex_init(&dev->ethtool->rss_lock); 11248 11249 spin_lock_init(&dev->addr_list_lock); 11250 netdev_set_addr_lockdep_class(dev); 11251 11252 ret = dev_get_valid_name(net, dev, dev->name); 11253 if (ret < 0) 11254 goto out; 11255 11256 ret = -ENOMEM; 11257 dev->name_node = netdev_name_node_head_alloc(dev); 11258 if (!dev->name_node) 11259 goto out; 11260 11261 /* Init, if this function is available */ 11262 if (dev->netdev_ops->ndo_init) { 11263 ret = dev->netdev_ops->ndo_init(dev); 11264 if (ret) { 11265 if (ret > 0) 11266 ret = -EIO; 11267 goto err_free_name; 11268 } 11269 } 11270 11271 if (((dev->hw_features | dev->features) & 11272 NETIF_F_HW_VLAN_CTAG_FILTER) && 11273 (!dev->netdev_ops->ndo_vlan_rx_add_vid || 11274 !dev->netdev_ops->ndo_vlan_rx_kill_vid)) { 11275 netdev_WARN(dev, "Buggy VLAN acceleration in driver!\n"); 11276 ret = -EINVAL; 11277 goto err_uninit; 11278 } 11279 11280 ret = netdev_do_alloc_pcpu_stats(dev); 11281 if (ret) 11282 goto err_uninit; 11283 11284 ret = dev_index_reserve(net, dev->ifindex); 11285 if (ret < 0) 11286 goto err_free_pcpu; 11287 dev->ifindex = ret; 11288 11289 /* Transfer changeable features to wanted_features and enable 11290 * software offloads (GSO and GRO). 11291 */ 11292 dev->hw_features |= (NETIF_F_SOFT_FEATURES | NETIF_F_SOFT_FEATURES_OFF); 11293 dev->features |= NETIF_F_SOFT_FEATURES; 11294 11295 if (dev->udp_tunnel_nic_info) { 11296 dev->features |= NETIF_F_RX_UDP_TUNNEL_PORT; 11297 dev->hw_features |= NETIF_F_RX_UDP_TUNNEL_PORT; 11298 } 11299 11300 dev->wanted_features = dev->features & dev->hw_features; 11301 11302 if (!(dev->flags & IFF_LOOPBACK)) 11303 dev->hw_features |= NETIF_F_NOCACHE_COPY; 11304 11305 /* If IPv4 TCP segmentation offload is supported we should also 11306 * allow the device to enable segmenting the frame with the option 11307 * of ignoring a static IP ID value. This doesn't enable the 11308 * feature itself but allows the user to enable it later. 11309 */ 11310 if (dev->hw_features & NETIF_F_TSO) 11311 dev->hw_features |= NETIF_F_TSO_MANGLEID; 11312 if (dev->vlan_features & NETIF_F_TSO) 11313 dev->vlan_features |= NETIF_F_TSO_MANGLEID; 11314 if (dev->mpls_features & NETIF_F_TSO) 11315 dev->mpls_features |= NETIF_F_TSO_MANGLEID; 11316 if (dev->hw_enc_features & NETIF_F_TSO) 11317 dev->hw_enc_features |= NETIF_F_TSO_MANGLEID; 11318 11319 /* TSO_MANGLEID belongs in mangleid_features by definition */ 11320 dev->mangleid_features |= NETIF_F_TSO_MANGLEID; 11321 11322 /* Make NETIF_F_HIGHDMA inheritable to VLAN devices. 11323 */ 11324 dev->vlan_features |= NETIF_F_HIGHDMA; 11325 11326 /* Make NETIF_F_SG inheritable to tunnel devices. 11327 */ 11328 dev->hw_enc_features |= NETIF_F_SG | NETIF_F_GSO_PARTIAL; 11329 11330 /* Make NETIF_F_SG inheritable to MPLS. 11331 */ 11332 dev->mpls_features |= NETIF_F_SG; 11333 11334 ret = call_netdevice_notifiers(NETDEV_POST_INIT, dev); 11335 ret = notifier_to_errno(ret); 11336 if (ret) 11337 goto err_ifindex_release; 11338 11339 ret = netdev_register_kobject(dev); 11340 11341 netdev_lock(dev); 11342 WRITE_ONCE(dev->reg_state, ret ? NETREG_UNREGISTERED : NETREG_REGISTERED); 11343 netdev_unlock(dev); 11344 11345 if (ret) 11346 goto err_uninit_notify; 11347 11348 netdev_lock_ops(dev); 11349 __netdev_update_features(dev); 11350 netdev_unlock_ops(dev); 11351 11352 /* 11353 * Default initial state at registry is that the 11354 * device is present. 11355 */ 11356 11357 set_bit(__LINK_STATE_PRESENT, &dev->state); 11358 11359 linkwatch_init_dev(dev); 11360 11361 dev_init_scheduler(dev); 11362 11363 netdev_hold(dev, &dev->dev_registered_tracker, GFP_KERNEL); 11364 list_netdevice(dev); 11365 11366 add_device_randomness(dev->dev_addr, dev->addr_len); 11367 11368 /* If the device has permanent device address, driver should 11369 * set dev_addr and also addr_assign_type should be set to 11370 * NET_ADDR_PERM (default value). 11371 */ 11372 if (dev->addr_assign_type == NET_ADDR_PERM) 11373 memcpy(dev->perm_addr, dev->dev_addr, dev->addr_len); 11374 11375 /* Notify protocols, that a new device appeared. */ 11376 netdev_lock_ops(dev); 11377 ret = call_netdevice_notifiers(NETDEV_REGISTER, dev); 11378 netdev_unlock_ops(dev); 11379 ret = notifier_to_errno(ret); 11380 if (ret) { 11381 /* Expect explicit free_netdev() on failure */ 11382 dev->needs_free_netdev = false; 11383 unregister_netdevice_queue(dev, NULL); 11384 goto out; 11385 } 11386 /* 11387 * Prevent userspace races by waiting until the network 11388 * device is fully setup before sending notifications. 11389 */ 11390 if (!(dev->rtnl_link_ops && dev->rtnl_link_initializing)) 11391 rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U, GFP_KERNEL, 0, NULL); 11392 11393 out: 11394 return ret; 11395 11396 err_uninit_notify: 11397 call_netdevice_notifiers(NETDEV_PRE_UNINIT, dev); 11398 err_ifindex_release: 11399 dev_index_release(net, dev->ifindex); 11400 err_free_pcpu: 11401 netdev_do_free_pcpu_stats(dev); 11402 err_uninit: 11403 if (dev->netdev_ops->ndo_uninit) 11404 dev->netdev_ops->ndo_uninit(dev); 11405 if (dev->priv_destructor) 11406 dev->priv_destructor(dev); 11407 err_free_name: 11408 netdev_name_node_free(dev->name_node); 11409 goto out; 11410 } 11411 EXPORT_SYMBOL(register_netdevice); 11412 11413 /* Initialize the core of a dummy net device. 11414 * The setup steps dummy netdevs need which normal netdevs get by going 11415 * through register_netdevice(). 11416 */ 11417 static void init_dummy_netdev(struct net_device *dev) 11418 { 11419 /* make sure we BUG if trying to hit standard 11420 * register/unregister code path 11421 */ 11422 dev->reg_state = NETREG_DUMMY; 11423 11424 /* a dummy interface is started by default */ 11425 set_bit(__LINK_STATE_PRESENT, &dev->state); 11426 set_bit(__LINK_STATE_START, &dev->state); 11427 11428 /* Note : We dont allocate pcpu_refcnt for dummy devices, 11429 * because users of this 'device' dont need to change 11430 * its refcount. 11431 */ 11432 } 11433 11434 /** 11435 * register_netdev - register a network device 11436 * @dev: device to register 11437 * 11438 * Take a completed network device structure and add it to the kernel 11439 * interfaces. A %NETDEV_REGISTER message is sent to the netdev notifier 11440 * chain. 0 is returned on success. A negative errno code is returned 11441 * on a failure to set up the device, or if the name is a duplicate. 11442 * 11443 * This is a wrapper around register_netdevice that takes the rtnl semaphore 11444 * and expands the device name if you passed a format string to 11445 * alloc_netdev. 11446 */ 11447 int register_netdev(struct net_device *dev) 11448 { 11449 struct net *net = dev_net(dev); 11450 int err; 11451 11452 if (rtnl_net_lock_killable(net)) 11453 return -EINTR; 11454 11455 err = register_netdevice(dev); 11456 11457 rtnl_net_unlock(net); 11458 11459 return err; 11460 } 11461 EXPORT_SYMBOL(register_netdev); 11462 11463 int netdev_refcnt_read(const struct net_device *dev) 11464 { 11465 #ifdef CONFIG_PCPU_DEV_REFCNT 11466 int i, refcnt = 0; 11467 11468 for_each_possible_cpu(i) 11469 refcnt += *per_cpu_ptr(dev->pcpu_refcnt, i); 11470 return refcnt; 11471 #else 11472 return refcount_read(&dev->dev_refcnt); 11473 #endif 11474 } 11475 EXPORT_SYMBOL(netdev_refcnt_read); 11476 11477 int netdev_unregister_timeout_secs __read_mostly = 10; 11478 11479 #define WAIT_REFS_MIN_MSECS 1 11480 #define WAIT_REFS_MAX_MSECS 250 11481 /** 11482 * netdev_wait_allrefs_any - wait until all references are gone. 11483 * @list: list of net_devices to wait on 11484 * 11485 * This is called when unregistering network devices. 11486 * 11487 * Any protocol or device that holds a reference should register 11488 * for netdevice notification, and cleanup and put back the 11489 * reference if they receive an UNREGISTER event. 11490 * We can get stuck here if buggy protocols don't correctly 11491 * call dev_put. 11492 */ 11493 static struct net_device *netdev_wait_allrefs_any(struct list_head *list) 11494 { 11495 unsigned long rebroadcast_time, warning_time; 11496 struct net_device *dev; 11497 int wait = 0; 11498 11499 rebroadcast_time = warning_time = jiffies; 11500 11501 list_for_each_entry(dev, list, todo_list) 11502 if (netdev_refcnt_read(dev) == 1) 11503 return dev; 11504 11505 while (true) { 11506 if (time_after(jiffies, rebroadcast_time + 1 * HZ)) { 11507 rtnl_lock(); 11508 11509 /* Rebroadcast unregister notification */ 11510 list_for_each_entry(dev, list, todo_list) 11511 call_netdevice_notifiers(NETDEV_UNREGISTER, dev); 11512 11513 __rtnl_unlock(); 11514 rcu_barrier(); 11515 rtnl_lock(); 11516 11517 list_for_each_entry(dev, list, todo_list) 11518 if (test_bit(__LINK_STATE_LINKWATCH_PENDING, 11519 &dev->state)) { 11520 /* We must not have linkwatch events 11521 * pending on unregister. If this 11522 * happens, we simply run the queue 11523 * unscheduled, resulting in a noop 11524 * for this device. 11525 */ 11526 linkwatch_run_queue(); 11527 break; 11528 } 11529 11530 __rtnl_unlock(); 11531 11532 rebroadcast_time = jiffies; 11533 } 11534 11535 rcu_barrier(); 11536 11537 if (!wait) { 11538 wait = WAIT_REFS_MIN_MSECS; 11539 } else { 11540 msleep(wait); 11541 wait = min(wait << 1, WAIT_REFS_MAX_MSECS); 11542 } 11543 11544 list_for_each_entry(dev, list, todo_list) 11545 if (netdev_refcnt_read(dev) == 1) 11546 return dev; 11547 11548 if (time_after(jiffies, warning_time + 11549 READ_ONCE(netdev_unregister_timeout_secs) * HZ)) { 11550 list_for_each_entry(dev, list, todo_list) { 11551 pr_emerg("unregister_netdevice: waiting for %s to become free. Usage count = %d\n", 11552 dev->name, netdev_refcnt_read(dev)); 11553 ref_tracker_dir_print(&dev->refcnt_tracker, 10); 11554 } 11555 11556 warning_time = jiffies; 11557 } 11558 } 11559 } 11560 11561 /* The sequence is: 11562 * 11563 * rtnl_lock(); 11564 * ... 11565 * register_netdevice(x1); 11566 * register_netdevice(x2); 11567 * ... 11568 * unregister_netdevice(y1); 11569 * unregister_netdevice(y2); 11570 * ... 11571 * rtnl_unlock(); 11572 * free_netdev(y1); 11573 * free_netdev(y2); 11574 * 11575 * We are invoked by rtnl_unlock(). 11576 * This allows us to deal with problems: 11577 * 1) We can delete sysfs objects which invoke hotplug 11578 * without deadlocking with linkwatch via keventd. 11579 * 2) Since we run with the RTNL semaphore not held, we can sleep 11580 * safely in order to wait for the netdev refcnt to drop to zero. 11581 * 11582 * We must not return until all unregister events added during 11583 * the interval the lock was held have been completed. 11584 */ 11585 void netdev_run_todo(void) 11586 { 11587 struct net_device *dev, *tmp; 11588 struct list_head list; 11589 int cnt; 11590 #ifdef CONFIG_LOCKDEP 11591 struct list_head unlink_list; 11592 11593 list_replace_init(&net_unlink_list, &unlink_list); 11594 11595 while (!list_empty(&unlink_list)) { 11596 dev = list_first_entry(&unlink_list, struct net_device, 11597 unlink_list); 11598 list_del_init(&dev->unlink_list); 11599 dev->nested_level = dev->lower_level - 1; 11600 } 11601 #endif 11602 11603 /* Snapshot list, allow later requests */ 11604 list_replace_init(&net_todo_list, &list); 11605 11606 __rtnl_unlock(); 11607 11608 /* Wait for rcu callbacks to finish before next phase */ 11609 if (!list_empty(&list)) 11610 rcu_barrier(); 11611 11612 list_for_each_entry_safe(dev, tmp, &list, todo_list) { 11613 if (unlikely(dev->reg_state != NETREG_UNREGISTERING)) { 11614 netdev_WARN(dev, "run_todo but not unregistering\n"); 11615 list_del(&dev->todo_list); 11616 continue; 11617 } 11618 11619 netdev_lock(dev); 11620 WRITE_ONCE(dev->reg_state, NETREG_UNREGISTERED); 11621 netdev_unlock(dev); 11622 linkwatch_sync_dev(dev); 11623 } 11624 11625 cnt = 0; 11626 while (!list_empty(&list)) { 11627 dev = netdev_wait_allrefs_any(&list); 11628 list_del(&dev->todo_list); 11629 11630 /* paranoia */ 11631 BUG_ON(netdev_refcnt_read(dev) != 1); 11632 BUG_ON(!list_empty(&dev->ptype_all)); 11633 BUG_ON(!list_empty(&dev->ptype_specific)); 11634 WARN_ON(rcu_access_pointer(dev->ip_ptr)); 11635 WARN_ON(rcu_access_pointer(dev->ip6_ptr)); 11636 11637 netdev_do_free_pcpu_stats(dev); 11638 if (dev->priv_destructor) 11639 dev->priv_destructor(dev); 11640 if (dev->needs_free_netdev) 11641 free_netdev(dev); 11642 11643 cnt++; 11644 11645 /* Free network device */ 11646 kobject_put(&dev->dev.kobj); 11647 } 11648 if (cnt && atomic_sub_and_test(cnt, &dev_unreg_count)) 11649 wake_up(&netdev_unregistering_wq); 11650 } 11651 11652 /* Collate per-cpu network dstats statistics 11653 * 11654 * Read per-cpu network statistics from dev->dstats and populate the related 11655 * fields in @s. 11656 */ 11657 static void dev_fetch_dstats(struct rtnl_link_stats64 *s, 11658 const struct pcpu_dstats __percpu *dstats) 11659 { 11660 int cpu; 11661 11662 for_each_possible_cpu(cpu) { 11663 u64 rx_packets, rx_bytes, rx_drops; 11664 u64 tx_packets, tx_bytes, tx_drops; 11665 const struct pcpu_dstats *stats; 11666 unsigned int start; 11667 11668 stats = per_cpu_ptr(dstats, cpu); 11669 do { 11670 start = u64_stats_fetch_begin(&stats->syncp); 11671 rx_packets = u64_stats_read(&stats->rx_packets); 11672 rx_bytes = u64_stats_read(&stats->rx_bytes); 11673 rx_drops = u64_stats_read(&stats->rx_drops); 11674 tx_packets = u64_stats_read(&stats->tx_packets); 11675 tx_bytes = u64_stats_read(&stats->tx_bytes); 11676 tx_drops = u64_stats_read(&stats->tx_drops); 11677 } while (u64_stats_fetch_retry(&stats->syncp, start)); 11678 11679 s->rx_packets += rx_packets; 11680 s->rx_bytes += rx_bytes; 11681 s->rx_dropped += rx_drops; 11682 s->tx_packets += tx_packets; 11683 s->tx_bytes += tx_bytes; 11684 s->tx_dropped += tx_drops; 11685 } 11686 } 11687 11688 /* ndo_get_stats64 implementation for dtstats-based accounting. 11689 * 11690 * Populate @s from dev->stats and dev->dstats. This is used internally by the 11691 * core for NETDEV_PCPU_STAT_DSTAT-type stats collection. 11692 */ 11693 static void dev_get_dstats64(const struct net_device *dev, 11694 struct rtnl_link_stats64 *s) 11695 { 11696 netdev_stats_to_stats64(s, &dev->stats); 11697 dev_fetch_dstats(s, dev->dstats); 11698 } 11699 11700 /* Convert net_device_stats to rtnl_link_stats64. rtnl_link_stats64 has 11701 * all the same fields in the same order as net_device_stats, with only 11702 * the type differing, but rtnl_link_stats64 may have additional fields 11703 * at the end for newer counters. 11704 */ 11705 void netdev_stats_to_stats64(struct rtnl_link_stats64 *stats64, 11706 const struct net_device_stats *netdev_stats) 11707 { 11708 size_t i, n = sizeof(*netdev_stats) / sizeof(atomic_long_t); 11709 const atomic_long_t *src = (atomic_long_t *)netdev_stats; 11710 u64 *dst = (u64 *)stats64; 11711 11712 BUILD_BUG_ON(n > sizeof(*stats64) / sizeof(u64)); 11713 for (i = 0; i < n; i++) 11714 dst[i] = (unsigned long)atomic_long_read(&src[i]); 11715 /* zero out counters that only exist in rtnl_link_stats64 */ 11716 memset((char *)stats64 + n * sizeof(u64), 0, 11717 sizeof(*stats64) - n * sizeof(u64)); 11718 } 11719 EXPORT_SYMBOL(netdev_stats_to_stats64); 11720 11721 static __cold struct net_device_core_stats __percpu *netdev_core_stats_alloc( 11722 struct net_device *dev) 11723 { 11724 struct net_device_core_stats __percpu *p; 11725 11726 p = alloc_percpu_gfp(struct net_device_core_stats, 11727 GFP_ATOMIC | __GFP_NOWARN); 11728 11729 if (p && cmpxchg(&dev->core_stats, NULL, p)) 11730 free_percpu(p); 11731 11732 /* This READ_ONCE() pairs with the cmpxchg() above */ 11733 return READ_ONCE(dev->core_stats); 11734 } 11735 11736 noinline void netdev_core_stats_inc(struct net_device *dev, u32 offset) 11737 { 11738 /* This READ_ONCE() pairs with the write in netdev_core_stats_alloc() */ 11739 struct net_device_core_stats __percpu *p = READ_ONCE(dev->core_stats); 11740 unsigned long __percpu *field; 11741 11742 if (unlikely(!p)) { 11743 p = netdev_core_stats_alloc(dev); 11744 if (!p) 11745 return; 11746 } 11747 11748 field = (unsigned long __percpu *)((void __percpu *)p + offset); 11749 this_cpu_inc(*field); 11750 } 11751 EXPORT_SYMBOL_GPL(netdev_core_stats_inc); 11752 11753 /** 11754 * dev_get_stats - get network device statistics 11755 * @dev: device to get statistics from 11756 * @storage: place to store stats 11757 * 11758 * Get network statistics from device. Return @storage. 11759 * The device driver may provide its own method by setting 11760 * dev->netdev_ops->get_stats64 or dev->netdev_ops->get_stats; 11761 * otherwise the internal statistics structure is used. 11762 */ 11763 struct rtnl_link_stats64 *dev_get_stats(struct net_device *dev, 11764 struct rtnl_link_stats64 *storage) 11765 { 11766 const struct net_device_ops *ops = dev->netdev_ops; 11767 const struct net_device_core_stats __percpu *p; 11768 11769 /* 11770 * IPv{4,6} and udp tunnels share common stat helpers and use 11771 * different stat type (NETDEV_PCPU_STAT_TSTATS vs 11772 * NETDEV_PCPU_STAT_DSTATS). Ensure the accounting is consistent. 11773 */ 11774 BUILD_BUG_ON(offsetof(struct pcpu_sw_netstats, rx_bytes) != 11775 offsetof(struct pcpu_dstats, rx_bytes)); 11776 BUILD_BUG_ON(offsetof(struct pcpu_sw_netstats, rx_packets) != 11777 offsetof(struct pcpu_dstats, rx_packets)); 11778 BUILD_BUG_ON(offsetof(struct pcpu_sw_netstats, tx_bytes) != 11779 offsetof(struct pcpu_dstats, tx_bytes)); 11780 BUILD_BUG_ON(offsetof(struct pcpu_sw_netstats, tx_packets) != 11781 offsetof(struct pcpu_dstats, tx_packets)); 11782 11783 if (ops->ndo_get_stats64) { 11784 memset(storage, 0, sizeof(*storage)); 11785 ops->ndo_get_stats64(dev, storage); 11786 } else if (ops->ndo_get_stats) { 11787 netdev_stats_to_stats64(storage, ops->ndo_get_stats(dev)); 11788 } else if (dev->pcpu_stat_type == NETDEV_PCPU_STAT_TSTATS) { 11789 dev_get_tstats64(dev, storage); 11790 } else if (dev->pcpu_stat_type == NETDEV_PCPU_STAT_DSTATS) { 11791 dev_get_dstats64(dev, storage); 11792 } else { 11793 netdev_stats_to_stats64(storage, &dev->stats); 11794 } 11795 11796 /* This READ_ONCE() pairs with the write in netdev_core_stats_alloc() */ 11797 p = READ_ONCE(dev->core_stats); 11798 if (p) { 11799 const struct net_device_core_stats *core_stats; 11800 int i; 11801 11802 for_each_possible_cpu(i) { 11803 core_stats = per_cpu_ptr(p, i); 11804 storage->rx_dropped += READ_ONCE(core_stats->rx_dropped); 11805 storage->tx_dropped += READ_ONCE(core_stats->tx_dropped); 11806 storage->rx_nohandler += READ_ONCE(core_stats->rx_nohandler); 11807 storage->rx_otherhost_dropped += READ_ONCE(core_stats->rx_otherhost_dropped); 11808 } 11809 } 11810 return storage; 11811 } 11812 EXPORT_SYMBOL(dev_get_stats); 11813 11814 /** 11815 * dev_fetch_sw_netstats - get per-cpu network device statistics 11816 * @s: place to store stats 11817 * @netstats: per-cpu network stats to read from 11818 * 11819 * Read per-cpu network statistics and populate the related fields in @s. 11820 */ 11821 void dev_fetch_sw_netstats(struct rtnl_link_stats64 *s, 11822 const struct pcpu_sw_netstats __percpu *netstats) 11823 { 11824 int cpu; 11825 11826 for_each_possible_cpu(cpu) { 11827 u64 rx_packets, rx_bytes, tx_packets, tx_bytes; 11828 const struct pcpu_sw_netstats *stats; 11829 unsigned int start; 11830 11831 stats = per_cpu_ptr(netstats, cpu); 11832 do { 11833 start = u64_stats_fetch_begin(&stats->syncp); 11834 rx_packets = u64_stats_read(&stats->rx_packets); 11835 rx_bytes = u64_stats_read(&stats->rx_bytes); 11836 tx_packets = u64_stats_read(&stats->tx_packets); 11837 tx_bytes = u64_stats_read(&stats->tx_bytes); 11838 } while (u64_stats_fetch_retry(&stats->syncp, start)); 11839 11840 s->rx_packets += rx_packets; 11841 s->rx_bytes += rx_bytes; 11842 s->tx_packets += tx_packets; 11843 s->tx_bytes += tx_bytes; 11844 } 11845 } 11846 EXPORT_SYMBOL_GPL(dev_fetch_sw_netstats); 11847 11848 /** 11849 * dev_get_tstats64 - ndo_get_stats64 implementation 11850 * @dev: device to get statistics from 11851 * @s: place to store stats 11852 * 11853 * Populate @s from dev->stats and dev->tstats. Can be used as 11854 * ndo_get_stats64() callback. 11855 */ 11856 void dev_get_tstats64(struct net_device *dev, struct rtnl_link_stats64 *s) 11857 { 11858 netdev_stats_to_stats64(s, &dev->stats); 11859 dev_fetch_sw_netstats(s, dev->tstats); 11860 } 11861 EXPORT_SYMBOL_GPL(dev_get_tstats64); 11862 11863 struct netdev_queue *dev_ingress_queue_create(struct net_device *dev) 11864 { 11865 struct netdev_queue *queue = dev_ingress_queue(dev); 11866 11867 #ifdef CONFIG_NET_CLS_ACT 11868 if (queue) 11869 return queue; 11870 queue = kzalloc(sizeof(*queue), GFP_KERNEL); 11871 if (!queue) 11872 return NULL; 11873 netdev_init_one_queue(dev, queue, NULL); 11874 RCU_INIT_POINTER(queue->qdisc, &noop_qdisc); 11875 RCU_INIT_POINTER(queue->qdisc_sleeping, &noop_qdisc); 11876 rcu_assign_pointer(dev->ingress_queue, queue); 11877 #endif 11878 return queue; 11879 } 11880 11881 static const struct ethtool_ops default_ethtool_ops; 11882 11883 void netdev_set_default_ethtool_ops(struct net_device *dev, 11884 const struct ethtool_ops *ops) 11885 { 11886 if (dev->ethtool_ops == &default_ethtool_ops) 11887 dev->ethtool_ops = ops; 11888 } 11889 EXPORT_SYMBOL_GPL(netdev_set_default_ethtool_ops); 11890 11891 /** 11892 * netdev_sw_irq_coalesce_default_on() - enable SW IRQ coalescing by default 11893 * @dev: netdev to enable the IRQ coalescing on 11894 * 11895 * Sets a conservative default for SW IRQ coalescing. Users can use 11896 * sysfs attributes to override the default values. 11897 */ 11898 void netdev_sw_irq_coalesce_default_on(struct net_device *dev) 11899 { 11900 WARN_ON(dev->reg_state == NETREG_REGISTERED); 11901 11902 if (!IS_ENABLED(CONFIG_PREEMPT_RT)) { 11903 netdev_set_gro_flush_timeout(dev, 20000); 11904 netdev_set_defer_hard_irqs(dev, 1); 11905 } 11906 } 11907 EXPORT_SYMBOL_GPL(netdev_sw_irq_coalesce_default_on); 11908 11909 /** 11910 * alloc_netdev_mqs - allocate network device 11911 * @sizeof_priv: size of private data to allocate space for 11912 * @name: device name format string 11913 * @name_assign_type: origin of device name 11914 * @setup: callback to initialize device 11915 * @txqs: the number of TX subqueues to allocate 11916 * @rxqs: the number of RX subqueues to allocate 11917 * 11918 * Allocates a struct net_device with private data area for driver use 11919 * and performs basic initialization. Also allocates subqueue structs 11920 * for each queue on the device. 11921 */ 11922 struct net_device *alloc_netdev_mqs(int sizeof_priv, const char *name, 11923 unsigned char name_assign_type, 11924 void (*setup)(struct net_device *), 11925 unsigned int txqs, unsigned int rxqs) 11926 { 11927 struct net_device *dev; 11928 size_t napi_config_sz; 11929 unsigned int maxqs; 11930 11931 BUG_ON(strlen(name) >= sizeof(dev->name)); 11932 11933 if (txqs < 1) { 11934 pr_err("alloc_netdev: Unable to allocate device with zero queues\n"); 11935 return NULL; 11936 } 11937 11938 if (rxqs < 1) { 11939 pr_err("alloc_netdev: Unable to allocate device with zero RX queues\n"); 11940 return NULL; 11941 } 11942 11943 maxqs = max(txqs, rxqs); 11944 11945 dev = kvzalloc(struct_size(dev, priv, sizeof_priv), 11946 GFP_KERNEL_ACCOUNT | __GFP_RETRY_MAYFAIL); 11947 if (!dev) 11948 return NULL; 11949 11950 dev->priv_len = sizeof_priv; 11951 11952 ref_tracker_dir_init(&dev->refcnt_tracker, 128, "netdev"); 11953 #ifdef CONFIG_PCPU_DEV_REFCNT 11954 dev->pcpu_refcnt = alloc_percpu(int); 11955 if (!dev->pcpu_refcnt) 11956 goto free_dev; 11957 __dev_hold(dev); 11958 #else 11959 refcount_set(&dev->dev_refcnt, 1); 11960 #endif 11961 11962 if (dev_addr_init(dev)) 11963 goto free_pcpu; 11964 11965 dev_mc_init(dev); 11966 dev_uc_init(dev); 11967 11968 dev_net_set(dev, &init_net); 11969 11970 dev->gso_max_size = GSO_LEGACY_MAX_SIZE; 11971 dev->xdp_zc_max_segs = 1; 11972 dev->gso_max_segs = GSO_MAX_SEGS; 11973 dev->gro_max_size = GRO_LEGACY_MAX_SIZE; 11974 dev->gso_ipv4_max_size = GSO_LEGACY_MAX_SIZE; 11975 dev->gro_ipv4_max_size = GRO_LEGACY_MAX_SIZE; 11976 dev->tso_max_size = TSO_LEGACY_MAX_SIZE; 11977 dev->tso_max_segs = TSO_MAX_SEGS; 11978 dev->upper_level = 1; 11979 dev->lower_level = 1; 11980 #ifdef CONFIG_LOCKDEP 11981 dev->nested_level = 0; 11982 INIT_LIST_HEAD(&dev->unlink_list); 11983 #endif 11984 11985 INIT_LIST_HEAD(&dev->napi_list); 11986 INIT_LIST_HEAD(&dev->unreg_list); 11987 INIT_LIST_HEAD(&dev->close_list); 11988 INIT_LIST_HEAD(&dev->link_watch_list); 11989 INIT_LIST_HEAD(&dev->adj_list.upper); 11990 INIT_LIST_HEAD(&dev->adj_list.lower); 11991 INIT_LIST_HEAD(&dev->ptype_all); 11992 INIT_LIST_HEAD(&dev->ptype_specific); 11993 INIT_LIST_HEAD(&dev->net_notifier_list); 11994 #ifdef CONFIG_NET_SCHED 11995 hash_init(dev->qdisc_hash); 11996 #endif 11997 11998 mutex_init(&dev->lock); 11999 12000 dev->priv_flags = IFF_XMIT_DST_RELEASE | IFF_XMIT_DST_RELEASE_PERM; 12001 setup(dev); 12002 12003 if (!dev->tx_queue_len) { 12004 dev->priv_flags |= IFF_NO_QUEUE; 12005 dev->tx_queue_len = DEFAULT_TX_QUEUE_LEN; 12006 } 12007 12008 dev->num_tx_queues = txqs; 12009 dev->real_num_tx_queues = txqs; 12010 if (netif_alloc_netdev_queues(dev)) 12011 goto free_all; 12012 12013 dev->num_rx_queues = rxqs; 12014 dev->real_num_rx_queues = rxqs; 12015 if (netif_alloc_rx_queues(dev)) 12016 goto free_all; 12017 dev->ethtool = kzalloc(sizeof(*dev->ethtool), GFP_KERNEL_ACCOUNT); 12018 if (!dev->ethtool) 12019 goto free_all; 12020 12021 dev->cfg = kzalloc(sizeof(*dev->cfg), GFP_KERNEL_ACCOUNT); 12022 if (!dev->cfg) 12023 goto free_all; 12024 dev->cfg_pending = dev->cfg; 12025 12026 dev->num_napi_configs = maxqs; 12027 napi_config_sz = array_size(maxqs, sizeof(*dev->napi_config)); 12028 dev->napi_config = kvzalloc(napi_config_sz, GFP_KERNEL_ACCOUNT); 12029 if (!dev->napi_config) 12030 goto free_all; 12031 12032 strscpy(dev->name, name); 12033 dev->name_assign_type = name_assign_type; 12034 dev->group = INIT_NETDEV_GROUP; 12035 if (!dev->ethtool_ops) 12036 dev->ethtool_ops = &default_ethtool_ops; 12037 12038 nf_hook_netdev_init(dev); 12039 12040 return dev; 12041 12042 free_all: 12043 free_netdev(dev); 12044 return NULL; 12045 12046 free_pcpu: 12047 #ifdef CONFIG_PCPU_DEV_REFCNT 12048 free_percpu(dev->pcpu_refcnt); 12049 free_dev: 12050 #endif 12051 kvfree(dev); 12052 return NULL; 12053 } 12054 EXPORT_SYMBOL(alloc_netdev_mqs); 12055 12056 static void netdev_napi_exit(struct net_device *dev) 12057 { 12058 if (!list_empty(&dev->napi_list)) { 12059 struct napi_struct *p, *n; 12060 12061 netdev_lock(dev); 12062 list_for_each_entry_safe(p, n, &dev->napi_list, dev_list) 12063 __netif_napi_del_locked(p); 12064 netdev_unlock(dev); 12065 12066 synchronize_net(); 12067 } 12068 12069 kvfree(dev->napi_config); 12070 } 12071 12072 /** 12073 * free_netdev - free network device 12074 * @dev: device 12075 * 12076 * This function does the last stage of destroying an allocated device 12077 * interface. The reference to the device object is released. If this 12078 * is the last reference then it will be freed.Must be called in process 12079 * context. 12080 */ 12081 void free_netdev(struct net_device *dev) 12082 { 12083 might_sleep(); 12084 12085 /* When called immediately after register_netdevice() failed the unwind 12086 * handling may still be dismantling the device. Handle that case by 12087 * deferring the free. 12088 */ 12089 if (dev->reg_state == NETREG_UNREGISTERING) { 12090 ASSERT_RTNL(); 12091 dev->needs_free_netdev = true; 12092 return; 12093 } 12094 12095 WARN_ON(dev->cfg != dev->cfg_pending); 12096 kfree(dev->cfg); 12097 kfree(dev->ethtool); 12098 netif_free_tx_queues(dev); 12099 netif_free_rx_queues(dev); 12100 12101 kfree(rcu_dereference_protected(dev->ingress_queue, 1)); 12102 12103 /* Flush device addresses */ 12104 dev_addr_flush(dev); 12105 12106 netdev_napi_exit(dev); 12107 12108 netif_del_cpu_rmap(dev); 12109 12110 ref_tracker_dir_exit(&dev->refcnt_tracker); 12111 #ifdef CONFIG_PCPU_DEV_REFCNT 12112 free_percpu(dev->pcpu_refcnt); 12113 dev->pcpu_refcnt = NULL; 12114 #endif 12115 free_percpu(dev->core_stats); 12116 dev->core_stats = NULL; 12117 free_percpu(dev->xdp_bulkq); 12118 dev->xdp_bulkq = NULL; 12119 12120 netdev_free_phy_link_topology(dev); 12121 12122 mutex_destroy(&dev->lock); 12123 12124 /* Compatibility with error handling in drivers */ 12125 if (dev->reg_state == NETREG_UNINITIALIZED || 12126 dev->reg_state == NETREG_DUMMY) { 12127 kvfree(dev); 12128 return; 12129 } 12130 12131 BUG_ON(dev->reg_state != NETREG_UNREGISTERED); 12132 WRITE_ONCE(dev->reg_state, NETREG_RELEASED); 12133 12134 /* will free via device release */ 12135 put_device(&dev->dev); 12136 } 12137 EXPORT_SYMBOL(free_netdev); 12138 12139 /** 12140 * alloc_netdev_dummy - Allocate and initialize a dummy net device. 12141 * @sizeof_priv: size of private data to allocate space for 12142 * 12143 * Return: the allocated net_device on success, NULL otherwise 12144 */ 12145 struct net_device *alloc_netdev_dummy(int sizeof_priv) 12146 { 12147 return alloc_netdev(sizeof_priv, "dummy#", NET_NAME_UNKNOWN, 12148 init_dummy_netdev); 12149 } 12150 EXPORT_SYMBOL_GPL(alloc_netdev_dummy); 12151 12152 /** 12153 * synchronize_net - Synchronize with packet receive processing 12154 * 12155 * Wait for packets currently being received to be done. 12156 * Does not block later packets from starting. 12157 */ 12158 void synchronize_net(void) 12159 { 12160 might_sleep(); 12161 if (from_cleanup_net() || rtnl_is_locked()) 12162 synchronize_rcu_expedited(); 12163 else 12164 synchronize_rcu(); 12165 } 12166 EXPORT_SYMBOL(synchronize_net); 12167 12168 static void netdev_rss_contexts_free(struct net_device *dev) 12169 { 12170 struct ethtool_rxfh_context *ctx; 12171 unsigned long context; 12172 12173 mutex_lock(&dev->ethtool->rss_lock); 12174 xa_for_each(&dev->ethtool->rss_ctx, context, ctx) { 12175 xa_erase(&dev->ethtool->rss_ctx, context); 12176 dev->ethtool_ops->remove_rxfh_context(dev, ctx, context, NULL); 12177 kfree(ctx); 12178 } 12179 xa_destroy(&dev->ethtool->rss_ctx); 12180 mutex_unlock(&dev->ethtool->rss_lock); 12181 } 12182 12183 /** 12184 * unregister_netdevice_queue - remove device from the kernel 12185 * @dev: device 12186 * @head: list 12187 * 12188 * This function shuts down a device interface and removes it 12189 * from the kernel tables. 12190 * If head not NULL, device is queued to be unregistered later. 12191 * 12192 * Callers must hold the rtnl semaphore. You may want 12193 * unregister_netdev() instead of this. 12194 */ 12195 12196 void unregister_netdevice_queue(struct net_device *dev, struct list_head *head) 12197 { 12198 ASSERT_RTNL(); 12199 12200 if (head) { 12201 list_move_tail(&dev->unreg_list, head); 12202 } else { 12203 LIST_HEAD(single); 12204 12205 list_add(&dev->unreg_list, &single); 12206 unregister_netdevice_many(&single); 12207 } 12208 } 12209 EXPORT_SYMBOL(unregister_netdevice_queue); 12210 12211 static void dev_memory_provider_uninstall(struct net_device *dev) 12212 { 12213 unsigned int i; 12214 12215 for (i = 0; i < dev->real_num_rx_queues; i++) { 12216 struct netdev_rx_queue *rxq = &dev->_rx[i]; 12217 struct pp_memory_provider_params *p = &rxq->mp_params; 12218 12219 if (p->mp_ops && p->mp_ops->uninstall) 12220 p->mp_ops->uninstall(rxq->mp_params.mp_priv, rxq); 12221 } 12222 } 12223 12224 /* devices must be UP and netdev_lock()'d */ 12225 static void netif_close_many_and_unlock(struct list_head *close_head) 12226 { 12227 struct net_device *dev, *tmp; 12228 12229 netif_close_many(close_head, false); 12230 12231 /* ... now unlock them */ 12232 list_for_each_entry_safe(dev, tmp, close_head, close_list) { 12233 netdev_unlock(dev); 12234 list_del_init(&dev->close_list); 12235 } 12236 } 12237 12238 static void netif_close_many_and_unlock_cond(struct list_head *close_head) 12239 { 12240 #ifdef CONFIG_LOCKDEP 12241 /* We can only track up to MAX_LOCK_DEPTH locks per task. 12242 * 12243 * Reserve half the available slots for additional locks possibly 12244 * taken by notifiers and (soft)irqs. 12245 */ 12246 unsigned int limit = MAX_LOCK_DEPTH / 2; 12247 12248 if (lockdep_depth(current) > limit) 12249 netif_close_many_and_unlock(close_head); 12250 #endif 12251 } 12252 12253 void unregister_netdevice_many_notify(struct list_head *head, 12254 u32 portid, const struct nlmsghdr *nlh) 12255 { 12256 struct net_device *dev, *tmp; 12257 LIST_HEAD(close_head); 12258 int cnt = 0; 12259 12260 BUG_ON(dev_boot_phase); 12261 ASSERT_RTNL(); 12262 12263 if (list_empty(head)) 12264 return; 12265 12266 list_for_each_entry_safe(dev, tmp, head, unreg_list) { 12267 /* Some devices call without registering 12268 * for initialization unwind. Remove those 12269 * devices and proceed with the remaining. 12270 */ 12271 if (dev->reg_state == NETREG_UNINITIALIZED) { 12272 pr_debug("unregister_netdevice: device %s/%p never was registered\n", 12273 dev->name, dev); 12274 12275 WARN_ON(1); 12276 list_del(&dev->unreg_list); 12277 continue; 12278 } 12279 dev->dismantle = true; 12280 BUG_ON(dev->reg_state != NETREG_REGISTERED); 12281 } 12282 12283 /* If device is running, close it first. Start with ops locked... */ 12284 list_for_each_entry(dev, head, unreg_list) { 12285 if (!(dev->flags & IFF_UP)) 12286 continue; 12287 if (netdev_need_ops_lock(dev)) { 12288 list_add_tail(&dev->close_list, &close_head); 12289 netdev_lock(dev); 12290 } 12291 netif_close_many_and_unlock_cond(&close_head); 12292 } 12293 netif_close_many_and_unlock(&close_head); 12294 /* ... now go over the rest. */ 12295 list_for_each_entry(dev, head, unreg_list) { 12296 if (!netdev_need_ops_lock(dev)) 12297 list_add_tail(&dev->close_list, &close_head); 12298 } 12299 netif_close_many(&close_head, true); 12300 12301 list_for_each_entry(dev, head, unreg_list) { 12302 /* And unlink it from device chain. */ 12303 unlist_netdevice(dev); 12304 netdev_lock(dev); 12305 WRITE_ONCE(dev->reg_state, NETREG_UNREGISTERING); 12306 netdev_unlock(dev); 12307 } 12308 flush_all_backlogs(); 12309 12310 synchronize_net(); 12311 12312 list_for_each_entry(dev, head, unreg_list) { 12313 struct sk_buff *skb = NULL; 12314 12315 /* Shutdown queueing discipline. */ 12316 netdev_lock_ops(dev); 12317 dev_shutdown(dev); 12318 dev_tcx_uninstall(dev); 12319 dev_xdp_uninstall(dev); 12320 dev_memory_provider_uninstall(dev); 12321 netdev_unlock_ops(dev); 12322 bpf_dev_bound_netdev_unregister(dev); 12323 12324 netdev_offload_xstats_disable_all(dev); 12325 12326 /* Notify protocols, that we are about to destroy 12327 * this device. They should clean all the things. 12328 */ 12329 call_netdevice_notifiers(NETDEV_UNREGISTER, dev); 12330 12331 if (!(dev->rtnl_link_ops && dev->rtnl_link_initializing)) 12332 skb = rtmsg_ifinfo_build_skb(RTM_DELLINK, dev, ~0U, 0, 12333 GFP_KERNEL, NULL, 0, 12334 portid, nlh); 12335 12336 /* 12337 * Flush the unicast and multicast chains 12338 */ 12339 dev_uc_flush(dev); 12340 dev_mc_flush(dev); 12341 12342 netdev_name_node_alt_flush(dev); 12343 netdev_name_node_free(dev->name_node); 12344 12345 netdev_rss_contexts_free(dev); 12346 12347 call_netdevice_notifiers(NETDEV_PRE_UNINIT, dev); 12348 12349 if (dev->netdev_ops->ndo_uninit) 12350 dev->netdev_ops->ndo_uninit(dev); 12351 12352 mutex_destroy(&dev->ethtool->rss_lock); 12353 12354 net_shaper_flush_netdev(dev); 12355 12356 if (skb) 12357 rtmsg_ifinfo_send(skb, dev, GFP_KERNEL, portid, nlh); 12358 12359 /* Notifier chain MUST detach us all upper devices. */ 12360 WARN_ON(netdev_has_any_upper_dev(dev)); 12361 WARN_ON(netdev_has_any_lower_dev(dev)); 12362 12363 /* Remove entries from kobject tree */ 12364 netdev_unregister_kobject(dev); 12365 #ifdef CONFIG_XPS 12366 /* Remove XPS queueing entries */ 12367 netif_reset_xps_queues_gt(dev, 0); 12368 #endif 12369 } 12370 12371 synchronize_net(); 12372 12373 list_for_each_entry(dev, head, unreg_list) { 12374 netdev_put(dev, &dev->dev_registered_tracker); 12375 net_set_todo(dev); 12376 cnt++; 12377 } 12378 atomic_add(cnt, &dev_unreg_count); 12379 12380 list_del(head); 12381 } 12382 12383 /** 12384 * unregister_netdevice_many - unregister many devices 12385 * @head: list of devices 12386 * 12387 * Note: As most callers use a stack allocated list_head, 12388 * we force a list_del() to make sure stack won't be corrupted later. 12389 */ 12390 void unregister_netdevice_many(struct list_head *head) 12391 { 12392 unregister_netdevice_many_notify(head, 0, NULL); 12393 } 12394 EXPORT_SYMBOL(unregister_netdevice_many); 12395 12396 /** 12397 * unregister_netdev - remove device from the kernel 12398 * @dev: device 12399 * 12400 * This function shuts down a device interface and removes it 12401 * from the kernel tables. 12402 * 12403 * This is just a wrapper for unregister_netdevice that takes 12404 * the rtnl semaphore. In general you want to use this and not 12405 * unregister_netdevice. 12406 */ 12407 void unregister_netdev(struct net_device *dev) 12408 { 12409 rtnl_net_dev_lock(dev); 12410 unregister_netdevice(dev); 12411 rtnl_net_dev_unlock(dev); 12412 } 12413 EXPORT_SYMBOL(unregister_netdev); 12414 12415 int __dev_change_net_namespace(struct net_device *dev, struct net *net, 12416 const char *pat, int new_ifindex, 12417 struct netlink_ext_ack *extack) 12418 { 12419 struct netdev_name_node *name_node; 12420 struct net *net_old = dev_net(dev); 12421 char new_name[IFNAMSIZ] = {}; 12422 int err, new_nsid; 12423 12424 ASSERT_RTNL(); 12425 12426 /* Don't allow namespace local devices to be moved. */ 12427 err = -EINVAL; 12428 if (dev->netns_immutable) { 12429 NL_SET_ERR_MSG(extack, "The interface netns is immutable"); 12430 goto out; 12431 } 12432 12433 /* Ensure the device has been registered */ 12434 if (dev->reg_state != NETREG_REGISTERED) { 12435 NL_SET_ERR_MSG(extack, "The interface isn't registered"); 12436 goto out; 12437 } 12438 12439 /* Get out if there is nothing todo */ 12440 err = 0; 12441 if (net_eq(net_old, net)) 12442 goto out; 12443 12444 /* Pick the destination device name, and ensure 12445 * we can use it in the destination network namespace. 12446 */ 12447 err = -EEXIST; 12448 if (netdev_name_in_use(net, dev->name)) { 12449 /* We get here if we can't use the current device name */ 12450 if (!pat) { 12451 NL_SET_ERR_MSG(extack, 12452 "An interface with the same name exists in the target netns"); 12453 goto out; 12454 } 12455 err = dev_prep_valid_name(net, dev, pat, new_name, EEXIST); 12456 if (err < 0) { 12457 NL_SET_ERR_MSG_FMT(extack, 12458 "Unable to use '%s' for the new interface name in the target netns", 12459 pat); 12460 goto out; 12461 } 12462 } 12463 /* Check that none of the altnames conflicts. */ 12464 err = -EEXIST; 12465 netdev_for_each_altname(dev, name_node) { 12466 if (netdev_name_in_use(net, name_node->name)) { 12467 NL_SET_ERR_MSG_FMT(extack, 12468 "An interface with the altname %s exists in the target netns", 12469 name_node->name); 12470 goto out; 12471 } 12472 } 12473 12474 /* Check that new_ifindex isn't used yet. */ 12475 if (new_ifindex) { 12476 err = dev_index_reserve(net, new_ifindex); 12477 if (err < 0) { 12478 NL_SET_ERR_MSG_FMT(extack, 12479 "The ifindex %d is not available in the target netns", 12480 new_ifindex); 12481 goto out; 12482 } 12483 } else { 12484 /* If there is an ifindex conflict assign a new one */ 12485 err = dev_index_reserve(net, dev->ifindex); 12486 if (err == -EBUSY) 12487 err = dev_index_reserve(net, 0); 12488 if (err < 0) { 12489 NL_SET_ERR_MSG(extack, 12490 "Unable to allocate a new ifindex in the target netns"); 12491 goto out; 12492 } 12493 new_ifindex = err; 12494 } 12495 12496 /* 12497 * And now a mini version of register_netdevice unregister_netdevice. 12498 */ 12499 12500 netdev_lock_ops(dev); 12501 /* If device is running close it first. */ 12502 netif_close(dev); 12503 /* And unlink it from device chain */ 12504 unlist_netdevice(dev); 12505 12506 if (!netdev_need_ops_lock(dev)) 12507 netdev_lock(dev); 12508 dev->moving_ns = true; 12509 netdev_unlock(dev); 12510 12511 synchronize_net(); 12512 12513 /* Shutdown queueing discipline. */ 12514 netdev_lock_ops(dev); 12515 dev_shutdown(dev); 12516 netdev_unlock_ops(dev); 12517 12518 /* Notify protocols, that we are about to destroy 12519 * this device. They should clean all the things. 12520 * 12521 * Note that dev->reg_state stays at NETREG_REGISTERED. 12522 * This is wanted because this way 8021q and macvlan know 12523 * the device is just moving and can keep their slaves up. 12524 */ 12525 call_netdevice_notifiers(NETDEV_UNREGISTER, dev); 12526 rcu_barrier(); 12527 12528 new_nsid = peernet2id_alloc(dev_net(dev), net, GFP_KERNEL); 12529 12530 rtmsg_ifinfo_newnet(RTM_DELLINK, dev, ~0U, GFP_KERNEL, &new_nsid, 12531 new_ifindex); 12532 12533 /* 12534 * Flush the unicast and multicast chains 12535 */ 12536 dev_uc_flush(dev); 12537 dev_mc_flush(dev); 12538 12539 /* Send a netdev-removed uevent to the old namespace */ 12540 kobject_uevent(&dev->dev.kobj, KOBJ_REMOVE); 12541 netdev_adjacent_del_links(dev); 12542 12543 /* Move per-net netdevice notifiers that are following the netdevice */ 12544 move_netdevice_notifiers_dev_net(dev, net); 12545 12546 /* Actually switch the network namespace */ 12547 netdev_lock(dev); 12548 dev_net_set(dev, net); 12549 netdev_unlock(dev); 12550 dev->ifindex = new_ifindex; 12551 12552 if (new_name[0]) { 12553 /* Rename the netdev to prepared name */ 12554 write_seqlock_bh(&netdev_rename_lock); 12555 strscpy(dev->name, new_name, IFNAMSIZ); 12556 write_sequnlock_bh(&netdev_rename_lock); 12557 } 12558 12559 /* Fixup kobjects */ 12560 dev_set_uevent_suppress(&dev->dev, 1); 12561 err = device_rename(&dev->dev, dev->name); 12562 dev_set_uevent_suppress(&dev->dev, 0); 12563 WARN_ON(err); 12564 12565 /* Send a netdev-add uevent to the new namespace */ 12566 kobject_uevent(&dev->dev.kobj, KOBJ_ADD); 12567 netdev_adjacent_add_links(dev); 12568 12569 /* Adapt owner in case owning user namespace of target network 12570 * namespace is different from the original one. 12571 */ 12572 err = netdev_change_owner(dev, net_old, net); 12573 WARN_ON(err); 12574 12575 netdev_lock(dev); 12576 dev->moving_ns = false; 12577 if (!netdev_need_ops_lock(dev)) 12578 netdev_unlock(dev); 12579 12580 /* Add the device back in the hashes */ 12581 list_netdevice(dev); 12582 /* Notify protocols, that a new device appeared. */ 12583 call_netdevice_notifiers(NETDEV_REGISTER, dev); 12584 netdev_unlock_ops(dev); 12585 12586 /* 12587 * Prevent userspace races by waiting until the network 12588 * device is fully setup before sending notifications. 12589 */ 12590 rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U, GFP_KERNEL, 0, NULL); 12591 12592 synchronize_net(); 12593 err = 0; 12594 out: 12595 return err; 12596 } 12597 12598 static int dev_cpu_dead(unsigned int oldcpu) 12599 { 12600 struct sk_buff **list_skb; 12601 struct sk_buff *skb; 12602 unsigned int cpu; 12603 struct softnet_data *sd, *oldsd, *remsd = NULL; 12604 12605 local_irq_disable(); 12606 cpu = smp_processor_id(); 12607 sd = &per_cpu(softnet_data, cpu); 12608 oldsd = &per_cpu(softnet_data, oldcpu); 12609 12610 /* Find end of our completion_queue. */ 12611 list_skb = &sd->completion_queue; 12612 while (*list_skb) 12613 list_skb = &(*list_skb)->next; 12614 /* Append completion queue from offline CPU. */ 12615 *list_skb = oldsd->completion_queue; 12616 oldsd->completion_queue = NULL; 12617 12618 /* Append output queue from offline CPU. */ 12619 if (oldsd->output_queue) { 12620 *sd->output_queue_tailp = oldsd->output_queue; 12621 sd->output_queue_tailp = oldsd->output_queue_tailp; 12622 oldsd->output_queue = NULL; 12623 oldsd->output_queue_tailp = &oldsd->output_queue; 12624 } 12625 /* Append NAPI poll list from offline CPU, with one exception : 12626 * process_backlog() must be called by cpu owning percpu backlog. 12627 * We properly handle process_queue & input_pkt_queue later. 12628 */ 12629 while (!list_empty(&oldsd->poll_list)) { 12630 struct napi_struct *napi = list_first_entry(&oldsd->poll_list, 12631 struct napi_struct, 12632 poll_list); 12633 12634 list_del_init(&napi->poll_list); 12635 if (napi->poll == process_backlog) 12636 napi->state &= NAPIF_STATE_THREADED; 12637 else 12638 ____napi_schedule(sd, napi); 12639 } 12640 12641 raise_softirq_irqoff(NET_TX_SOFTIRQ); 12642 local_irq_enable(); 12643 12644 if (!use_backlog_threads()) { 12645 #ifdef CONFIG_RPS 12646 remsd = oldsd->rps_ipi_list; 12647 oldsd->rps_ipi_list = NULL; 12648 #endif 12649 /* send out pending IPI's on offline CPU */ 12650 net_rps_send_ipi(remsd); 12651 } 12652 12653 /* Process offline CPU's input_pkt_queue */ 12654 while ((skb = __skb_dequeue(&oldsd->process_queue))) { 12655 netif_rx(skb); 12656 rps_input_queue_head_incr(oldsd); 12657 } 12658 while ((skb = skb_dequeue(&oldsd->input_pkt_queue))) { 12659 netif_rx(skb); 12660 rps_input_queue_head_incr(oldsd); 12661 } 12662 12663 return 0; 12664 } 12665 12666 /** 12667 * netdev_increment_features - increment feature set by one 12668 * @all: current feature set 12669 * @one: new feature set 12670 * @mask: mask feature set 12671 * 12672 * Computes a new feature set after adding a device with feature set 12673 * @one to the master device with current feature set @all. Will not 12674 * enable anything that is off in @mask. Returns the new feature set. 12675 */ 12676 netdev_features_t netdev_increment_features(netdev_features_t all, 12677 netdev_features_t one, netdev_features_t mask) 12678 { 12679 if (mask & NETIF_F_HW_CSUM) 12680 mask |= NETIF_F_CSUM_MASK; 12681 mask |= NETIF_F_VLAN_CHALLENGED; 12682 12683 all |= one & (NETIF_F_ONE_FOR_ALL | NETIF_F_CSUM_MASK) & mask; 12684 all &= one | ~NETIF_F_ALL_FOR_ALL; 12685 12686 /* If one device supports hw checksumming, set for all. */ 12687 if (all & NETIF_F_HW_CSUM) 12688 all &= ~(NETIF_F_CSUM_MASK & ~NETIF_F_HW_CSUM); 12689 12690 return all; 12691 } 12692 EXPORT_SYMBOL(netdev_increment_features); 12693 12694 /** 12695 * netdev_compute_master_upper_features - compute feature from lowers 12696 * @dev: the upper device 12697 * @update_header: whether to update upper device's header_len/headroom/tailroom 12698 * 12699 * Recompute the upper device's feature based on all lower devices. 12700 */ 12701 void netdev_compute_master_upper_features(struct net_device *dev, bool update_header) 12702 { 12703 unsigned int dst_release_flag = IFF_XMIT_DST_RELEASE | IFF_XMIT_DST_RELEASE_PERM; 12704 netdev_features_t gso_partial_features = MASTER_UPPER_DEV_GSO_PARTIAL_FEATURES; 12705 netdev_features_t xfrm_features = MASTER_UPPER_DEV_XFRM_FEATURES; 12706 netdev_features_t mpls_features = MASTER_UPPER_DEV_MPLS_FEATURES; 12707 netdev_features_t vlan_features = MASTER_UPPER_DEV_VLAN_FEATURES; 12708 netdev_features_t enc_features = MASTER_UPPER_DEV_ENC_FEATURES; 12709 unsigned short max_header_len = ETH_HLEN; 12710 unsigned int tso_max_size = TSO_MAX_SIZE; 12711 unsigned short max_headroom = 0; 12712 unsigned short max_tailroom = 0; 12713 u16 tso_max_segs = TSO_MAX_SEGS; 12714 struct net_device *lower_dev; 12715 struct list_head *iter; 12716 12717 mpls_features = netdev_base_features(mpls_features); 12718 vlan_features = netdev_base_features(vlan_features); 12719 enc_features = netdev_base_features(enc_features); 12720 12721 netdev_for_each_lower_dev(dev, lower_dev, iter) { 12722 gso_partial_features = netdev_increment_features(gso_partial_features, 12723 lower_dev->gso_partial_features, 12724 MASTER_UPPER_DEV_GSO_PARTIAL_FEATURES); 12725 12726 vlan_features = netdev_increment_features(vlan_features, 12727 lower_dev->vlan_features, 12728 MASTER_UPPER_DEV_VLAN_FEATURES); 12729 12730 enc_features = netdev_increment_features(enc_features, 12731 lower_dev->hw_enc_features, 12732 MASTER_UPPER_DEV_ENC_FEATURES); 12733 12734 if (IS_ENABLED(CONFIG_XFRM_OFFLOAD)) 12735 xfrm_features = netdev_increment_features(xfrm_features, 12736 lower_dev->hw_enc_features, 12737 MASTER_UPPER_DEV_XFRM_FEATURES); 12738 12739 mpls_features = netdev_increment_features(mpls_features, 12740 lower_dev->mpls_features, 12741 MASTER_UPPER_DEV_MPLS_FEATURES); 12742 12743 dst_release_flag &= lower_dev->priv_flags; 12744 12745 if (update_header) { 12746 max_header_len = max(max_header_len, lower_dev->hard_header_len); 12747 max_headroom = max(max_headroom, lower_dev->needed_headroom); 12748 max_tailroom = max(max_tailroom, lower_dev->needed_tailroom); 12749 } 12750 12751 tso_max_size = min(tso_max_size, lower_dev->tso_max_size); 12752 tso_max_segs = min(tso_max_segs, lower_dev->tso_max_segs); 12753 } 12754 12755 dev->gso_partial_features = gso_partial_features; 12756 dev->vlan_features = vlan_features; 12757 dev->hw_enc_features = enc_features | NETIF_F_GSO_ENCAP_ALL | 12758 NETIF_F_HW_VLAN_CTAG_TX | 12759 NETIF_F_HW_VLAN_STAG_TX; 12760 if (IS_ENABLED(CONFIG_XFRM_OFFLOAD)) 12761 dev->hw_enc_features |= xfrm_features; 12762 dev->mpls_features = mpls_features; 12763 12764 dev->priv_flags &= ~IFF_XMIT_DST_RELEASE; 12765 if ((dev->priv_flags & IFF_XMIT_DST_RELEASE_PERM) && 12766 dst_release_flag == (IFF_XMIT_DST_RELEASE | IFF_XMIT_DST_RELEASE_PERM)) 12767 dev->priv_flags |= IFF_XMIT_DST_RELEASE; 12768 12769 if (update_header) { 12770 dev->hard_header_len = max_header_len; 12771 dev->needed_headroom = max_headroom; 12772 dev->needed_tailroom = max_tailroom; 12773 } 12774 12775 netif_set_tso_max_segs(dev, tso_max_segs); 12776 netif_set_tso_max_size(dev, tso_max_size); 12777 12778 netdev_change_features(dev); 12779 } 12780 EXPORT_SYMBOL(netdev_compute_master_upper_features); 12781 12782 static struct hlist_head * __net_init netdev_create_hash(void) 12783 { 12784 int i; 12785 struct hlist_head *hash; 12786 12787 hash = kmalloc_array(NETDEV_HASHENTRIES, sizeof(*hash), GFP_KERNEL); 12788 if (hash != NULL) 12789 for (i = 0; i < NETDEV_HASHENTRIES; i++) 12790 INIT_HLIST_HEAD(&hash[i]); 12791 12792 return hash; 12793 } 12794 12795 /* Initialize per network namespace state */ 12796 static int __net_init netdev_init(struct net *net) 12797 { 12798 BUILD_BUG_ON(GRO_HASH_BUCKETS > 12799 BITS_PER_BYTE * sizeof_field(struct gro_node, bitmask)); 12800 12801 INIT_LIST_HEAD(&net->dev_base_head); 12802 12803 net->dev_name_head = netdev_create_hash(); 12804 if (net->dev_name_head == NULL) 12805 goto err_name; 12806 12807 net->dev_index_head = netdev_create_hash(); 12808 if (net->dev_index_head == NULL) 12809 goto err_idx; 12810 12811 xa_init_flags(&net->dev_by_index, XA_FLAGS_ALLOC1); 12812 12813 RAW_INIT_NOTIFIER_HEAD(&net->netdev_chain); 12814 12815 return 0; 12816 12817 err_idx: 12818 kfree(net->dev_name_head); 12819 err_name: 12820 return -ENOMEM; 12821 } 12822 12823 /** 12824 * netdev_drivername - network driver for the device 12825 * @dev: network device 12826 * 12827 * Determine network driver for device. 12828 */ 12829 const char *netdev_drivername(const struct net_device *dev) 12830 { 12831 const struct device_driver *driver; 12832 const struct device *parent; 12833 const char *empty = ""; 12834 12835 parent = dev->dev.parent; 12836 if (!parent) 12837 return empty; 12838 12839 driver = parent->driver; 12840 if (driver && driver->name) 12841 return driver->name; 12842 return empty; 12843 } 12844 12845 static void __netdev_printk(const char *level, const struct net_device *dev, 12846 struct va_format *vaf) 12847 { 12848 if (dev && dev->dev.parent) { 12849 dev_printk_emit(level[1] - '0', 12850 dev->dev.parent, 12851 "%s %s %s%s: %pV", 12852 dev_driver_string(dev->dev.parent), 12853 dev_name(dev->dev.parent), 12854 netdev_name(dev), netdev_reg_state(dev), 12855 vaf); 12856 } else if (dev) { 12857 printk("%s%s%s: %pV", 12858 level, netdev_name(dev), netdev_reg_state(dev), vaf); 12859 } else { 12860 printk("%s(NULL net_device): %pV", level, vaf); 12861 } 12862 } 12863 12864 void netdev_printk(const char *level, const struct net_device *dev, 12865 const char *format, ...) 12866 { 12867 struct va_format vaf; 12868 va_list args; 12869 12870 va_start(args, format); 12871 12872 vaf.fmt = format; 12873 vaf.va = &args; 12874 12875 __netdev_printk(level, dev, &vaf); 12876 12877 va_end(args); 12878 } 12879 EXPORT_SYMBOL(netdev_printk); 12880 12881 #define define_netdev_printk_level(func, level) \ 12882 void func(const struct net_device *dev, const char *fmt, ...) \ 12883 { \ 12884 struct va_format vaf; \ 12885 va_list args; \ 12886 \ 12887 va_start(args, fmt); \ 12888 \ 12889 vaf.fmt = fmt; \ 12890 vaf.va = &args; \ 12891 \ 12892 __netdev_printk(level, dev, &vaf); \ 12893 \ 12894 va_end(args); \ 12895 } \ 12896 EXPORT_SYMBOL(func); 12897 12898 define_netdev_printk_level(netdev_emerg, KERN_EMERG); 12899 define_netdev_printk_level(netdev_alert, KERN_ALERT); 12900 define_netdev_printk_level(netdev_crit, KERN_CRIT); 12901 define_netdev_printk_level(netdev_err, KERN_ERR); 12902 define_netdev_printk_level(netdev_warn, KERN_WARNING); 12903 define_netdev_printk_level(netdev_notice, KERN_NOTICE); 12904 define_netdev_printk_level(netdev_info, KERN_INFO); 12905 12906 static void __net_exit netdev_exit(struct net *net) 12907 { 12908 kfree(net->dev_name_head); 12909 kfree(net->dev_index_head); 12910 xa_destroy(&net->dev_by_index); 12911 if (net != &init_net) 12912 WARN_ON_ONCE(!list_empty(&net->dev_base_head)); 12913 } 12914 12915 static struct pernet_operations __net_initdata netdev_net_ops = { 12916 .init = netdev_init, 12917 .exit = netdev_exit, 12918 }; 12919 12920 static void __net_exit default_device_exit_net(struct net *net) 12921 { 12922 struct netdev_name_node *name_node, *tmp; 12923 struct net_device *dev, *aux; 12924 /* 12925 * Push all migratable network devices back to the 12926 * initial network namespace 12927 */ 12928 ASSERT_RTNL(); 12929 for_each_netdev_safe(net, dev, aux) { 12930 int err; 12931 char fb_name[IFNAMSIZ]; 12932 12933 /* Ignore unmoveable devices (i.e. loopback) */ 12934 if (dev->netns_immutable) 12935 continue; 12936 12937 /* Leave virtual devices for the generic cleanup */ 12938 if (dev->rtnl_link_ops && !dev->rtnl_link_ops->netns_refund) 12939 continue; 12940 12941 /* Push remaining network devices to init_net */ 12942 snprintf(fb_name, IFNAMSIZ, "dev%d", dev->ifindex); 12943 if (netdev_name_in_use(&init_net, fb_name)) 12944 snprintf(fb_name, IFNAMSIZ, "dev%%d"); 12945 12946 netdev_for_each_altname_safe(dev, name_node, tmp) 12947 if (netdev_name_in_use(&init_net, name_node->name)) 12948 __netdev_name_node_alt_destroy(name_node); 12949 12950 err = dev_change_net_namespace(dev, &init_net, fb_name); 12951 if (err) { 12952 pr_emerg("%s: failed to move %s to init_net: %d\n", 12953 __func__, dev->name, err); 12954 BUG(); 12955 } 12956 } 12957 } 12958 12959 static void __net_exit default_device_exit_batch(struct list_head *net_list) 12960 { 12961 /* At exit all network devices most be removed from a network 12962 * namespace. Do this in the reverse order of registration. 12963 * Do this across as many network namespaces as possible to 12964 * improve batching efficiency. 12965 */ 12966 struct net_device *dev; 12967 struct net *net; 12968 LIST_HEAD(dev_kill_list); 12969 12970 rtnl_lock(); 12971 list_for_each_entry(net, net_list, exit_list) { 12972 default_device_exit_net(net); 12973 cond_resched(); 12974 } 12975 12976 list_for_each_entry(net, net_list, exit_list) { 12977 for_each_netdev_reverse(net, dev) { 12978 if (dev->rtnl_link_ops && dev->rtnl_link_ops->dellink) 12979 dev->rtnl_link_ops->dellink(dev, &dev_kill_list); 12980 else 12981 unregister_netdevice_queue(dev, &dev_kill_list); 12982 } 12983 } 12984 unregister_netdevice_many(&dev_kill_list); 12985 rtnl_unlock(); 12986 } 12987 12988 static struct pernet_operations __net_initdata default_device_ops = { 12989 .exit_batch = default_device_exit_batch, 12990 }; 12991 12992 static void __init net_dev_struct_check(void) 12993 { 12994 /* TX read-mostly hotpath */ 12995 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_tx, priv_flags_fast); 12996 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_tx, netdev_ops); 12997 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_tx, header_ops); 12998 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_tx, _tx); 12999 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_tx, real_num_tx_queues); 13000 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_tx, gso_max_size); 13001 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_tx, gso_ipv4_max_size); 13002 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_tx, gso_max_segs); 13003 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_tx, gso_partial_features); 13004 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_tx, num_tc); 13005 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_tx, mtu); 13006 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_tx, needed_headroom); 13007 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_tx, tc_to_txq); 13008 #ifdef CONFIG_XPS 13009 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_tx, xps_maps); 13010 #endif 13011 #ifdef CONFIG_NETFILTER_EGRESS 13012 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_tx, nf_hooks_egress); 13013 #endif 13014 #ifdef CONFIG_NET_XGRESS 13015 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_tx, tcx_egress); 13016 #endif 13017 CACHELINE_ASSERT_GROUP_SIZE(struct net_device, net_device_read_tx, 160); 13018 13019 /* TXRX read-mostly hotpath */ 13020 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_txrx, lstats); 13021 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_txrx, state); 13022 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_txrx, flags); 13023 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_txrx, hard_header_len); 13024 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_txrx, features); 13025 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_txrx, ip6_ptr); 13026 CACHELINE_ASSERT_GROUP_SIZE(struct net_device, net_device_read_txrx, 46); 13027 13028 /* RX read-mostly hotpath */ 13029 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_rx, ptype_specific); 13030 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_rx, ifindex); 13031 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_rx, real_num_rx_queues); 13032 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_rx, _rx); 13033 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_rx, gro_max_size); 13034 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_rx, gro_ipv4_max_size); 13035 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_rx, rx_handler); 13036 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_rx, rx_handler_data); 13037 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_rx, nd_net); 13038 #ifdef CONFIG_NETPOLL 13039 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_rx, npinfo); 13040 #endif 13041 #ifdef CONFIG_NET_XGRESS 13042 CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_rx, tcx_ingress); 13043 #endif 13044 CACHELINE_ASSERT_GROUP_SIZE(struct net_device, net_device_read_rx, 92); 13045 } 13046 13047 /* 13048 * Initialize the DEV module. At boot time this walks the device list and 13049 * unhooks any devices that fail to initialise (normally hardware not 13050 * present) and leaves us with a valid list of present and active devices. 13051 * 13052 */ 13053 13054 /* We allocate 256 pages for each CPU if PAGE_SHIFT is 12 */ 13055 #define SYSTEM_PERCPU_PAGE_POOL_SIZE ((1 << 20) / PAGE_SIZE) 13056 13057 static int net_page_pool_create(int cpuid) 13058 { 13059 #if IS_ENABLED(CONFIG_PAGE_POOL) 13060 struct page_pool_params page_pool_params = { 13061 .pool_size = SYSTEM_PERCPU_PAGE_POOL_SIZE, 13062 .flags = PP_FLAG_SYSTEM_POOL, 13063 .nid = cpu_to_mem(cpuid), 13064 }; 13065 struct page_pool *pp_ptr; 13066 int err; 13067 13068 pp_ptr = page_pool_create_percpu(&page_pool_params, cpuid); 13069 if (IS_ERR(pp_ptr)) 13070 return -ENOMEM; 13071 13072 err = xdp_reg_page_pool(pp_ptr); 13073 if (err) { 13074 page_pool_destroy(pp_ptr); 13075 return err; 13076 } 13077 13078 per_cpu(system_page_pool.pool, cpuid) = pp_ptr; 13079 #endif 13080 return 0; 13081 } 13082 13083 static int backlog_napi_should_run(unsigned int cpu) 13084 { 13085 struct softnet_data *sd = per_cpu_ptr(&softnet_data, cpu); 13086 struct napi_struct *napi = &sd->backlog; 13087 13088 return test_bit(NAPI_STATE_SCHED_THREADED, &napi->state); 13089 } 13090 13091 static void run_backlog_napi(unsigned int cpu) 13092 { 13093 struct softnet_data *sd = per_cpu_ptr(&softnet_data, cpu); 13094 13095 napi_threaded_poll_loop(&sd->backlog); 13096 } 13097 13098 static void backlog_napi_setup(unsigned int cpu) 13099 { 13100 struct softnet_data *sd = per_cpu_ptr(&softnet_data, cpu); 13101 struct napi_struct *napi = &sd->backlog; 13102 13103 napi->thread = this_cpu_read(backlog_napi); 13104 set_bit(NAPI_STATE_THREADED, &napi->state); 13105 } 13106 13107 static struct smp_hotplug_thread backlog_threads = { 13108 .store = &backlog_napi, 13109 .thread_should_run = backlog_napi_should_run, 13110 .thread_fn = run_backlog_napi, 13111 .thread_comm = "backlog_napi/%u", 13112 .setup = backlog_napi_setup, 13113 }; 13114 13115 /* 13116 * This is called single threaded during boot, so no need 13117 * to take the rtnl semaphore. 13118 */ 13119 static int __init net_dev_init(void) 13120 { 13121 int i, rc = -ENOMEM; 13122 13123 BUG_ON(!dev_boot_phase); 13124 13125 net_dev_struct_check(); 13126 13127 if (dev_proc_init()) 13128 goto out; 13129 13130 if (netdev_kobject_init()) 13131 goto out; 13132 13133 for (i = 0; i < PTYPE_HASH_SIZE; i++) 13134 INIT_LIST_HEAD(&ptype_base[i]); 13135 13136 if (register_pernet_subsys(&netdev_net_ops)) 13137 goto out; 13138 13139 /* 13140 * Initialise the packet receive queues. 13141 */ 13142 13143 flush_backlogs_fallback = flush_backlogs_alloc(); 13144 if (!flush_backlogs_fallback) 13145 goto out; 13146 13147 for_each_possible_cpu(i) { 13148 struct softnet_data *sd = &per_cpu(softnet_data, i); 13149 13150 skb_queue_head_init(&sd->input_pkt_queue); 13151 skb_queue_head_init(&sd->process_queue); 13152 #ifdef CONFIG_XFRM_OFFLOAD 13153 skb_queue_head_init(&sd->xfrm_backlog); 13154 #endif 13155 INIT_LIST_HEAD(&sd->poll_list); 13156 sd->output_queue_tailp = &sd->output_queue; 13157 #ifdef CONFIG_RPS 13158 INIT_CSD(&sd->csd, rps_trigger_softirq, sd); 13159 sd->cpu = i; 13160 #endif 13161 INIT_CSD(&sd->defer_csd, trigger_rx_softirq, sd); 13162 13163 gro_init(&sd->backlog.gro); 13164 sd->backlog.poll = process_backlog; 13165 sd->backlog.weight = weight_p; 13166 INIT_LIST_HEAD(&sd->backlog.poll_list); 13167 13168 if (net_page_pool_create(i)) 13169 goto out; 13170 } 13171 net_hotdata.skb_defer_nodes = 13172 __alloc_percpu(sizeof(struct skb_defer_node) * nr_node_ids, 13173 __alignof__(struct skb_defer_node)); 13174 if (!net_hotdata.skb_defer_nodes) 13175 goto out; 13176 if (use_backlog_threads()) 13177 smpboot_register_percpu_thread(&backlog_threads); 13178 13179 dev_boot_phase = 0; 13180 13181 /* The loopback device is special if any other network devices 13182 * is present in a network namespace the loopback device must 13183 * be present. Since we now dynamically allocate and free the 13184 * loopback device ensure this invariant is maintained by 13185 * keeping the loopback device as the first device on the 13186 * list of network devices. Ensuring the loopback devices 13187 * is the first device that appears and the last network device 13188 * that disappears. 13189 */ 13190 if (register_pernet_device(&loopback_net_ops)) 13191 goto out; 13192 13193 if (register_pernet_device(&default_device_ops)) 13194 goto out; 13195 13196 open_softirq(NET_TX_SOFTIRQ, net_tx_action); 13197 open_softirq(NET_RX_SOFTIRQ, net_rx_action); 13198 13199 rc = cpuhp_setup_state_nocalls(CPUHP_NET_DEV_DEAD, "net/dev:dead", 13200 NULL, dev_cpu_dead); 13201 WARN_ON(rc < 0); 13202 rc = 0; 13203 13204 /* avoid static key IPIs to isolated CPUs */ 13205 if (housekeeping_enabled(HK_TYPE_MISC)) 13206 net_enable_timestamp(); 13207 out: 13208 if (rc < 0) { 13209 for_each_possible_cpu(i) { 13210 struct page_pool *pp_ptr; 13211 13212 pp_ptr = per_cpu(system_page_pool.pool, i); 13213 if (!pp_ptr) 13214 continue; 13215 13216 xdp_unreg_page_pool(pp_ptr); 13217 page_pool_destroy(pp_ptr); 13218 per_cpu(system_page_pool.pool, i) = NULL; 13219 } 13220 } 13221 13222 return rc; 13223 } 13224 13225 subsys_initcall(net_dev_init);