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, <waltje@uWalt.NL.Mugnet.ORG> 8 * Mark Evans, <evansmp@uhura.aston.ac.uk> 9 * 10 * Additional Authors: 11 * Florian la Roche <rzsfl@rz.uni-sb.de> 12 * Alan Cox <gw4pts@gw4pts.ampr.org> 13 * David Hinds <dahinds@users.sourceforge.net> 14 * Alexey Kuznetsov <kuznet@ms2.inr.ac.ru> 15 * Adam Sulmicki <adam@cfar.umd.edu> 16 * Pekka Riikonen <priikone@poesidon.pspt.fi> 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/bitops.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/mm.h> 81 #include <linux/mutex.h> 82 #include <linux/rwsem.h> 83 #include <linux/string.h> 84 #include <linux/mm.h> 85 #include <linux/socket.h> 86 #include <linux/sockios.h> 87 #include <linux/errno.h> 88 #include <linux/interrupt.h> 89 #include <linux/if_ether.h> 90 #include <linux/netdevice.h> 91 #include <linux/etherdevice.h> 92 #include <linux/ethtool.h> 93 #include <linux/skbuff.h> 94 #include <linux/kthread.h> 95 #include <linux/bpf.h> 96 #include <linux/bpf_trace.h> 97 #include <net/net_namespace.h> 98 #include <net/sock.h> 99 #include <net/busy_poll.h> 100 #include <linux/rtnetlink.h> 101 #include <linux/stat.h> 102 #include <net/dsa.h> 103 #include <net/dst.h> 104 #include <net/dst_metadata.h> 105 #include <net/gro.h> 106 #include <net/pkt_sched.h> 107 #include <net/pkt_cls.h> 108 #include <net/checksum.h> 109 #include <net/xfrm.h> 110 #include <linux/highmem.h> 111 #include <linux/init.h> 112 #include <linux/module.h> 113 #include <linux/netpoll.h> 114 #include <linux/rcupdate.h> 115 #include <linux/delay.h> 116 #include <net/iw_handler.h> 117 #include <asm/current.h> 118 #include <linux/audit.h> 119 #include <linux/dmaengine.h> 120 #include <linux/err.h> 121 #include <linux/ctype.h> 122 #include <linux/if_arp.h> 123 #include <linux/if_vlan.h> 124 #include <linux/ip.h> 125 #include <net/ip.h> 126 #include <net/mpls.h> 127 #include <linux/ipv6.h> 128 #include <linux/in.h> 129 #include <linux/jhash.h> 130 #include <linux/random.h> 131 #include <trace/events/napi.h> 132 #include <trace/events/net.h> 133 #include <trace/events/skb.h> 134 #include <trace/events/qdisc.h> 135 #include <linux/inetdevice.h> 136 #include <linux/cpu_rmap.h> 137 #include <linux/static_key.h> 138 #include <linux/hashtable.h> 139 #include <linux/vmalloc.h> 140 #include <linux/if_macvlan.h> 141 #include <linux/errqueue.h> 142 #include <linux/hrtimer.h> 143 #include <linux/netfilter_netdev.h> 144 #include <linux/crash_dump.h> 145 #include <linux/sctp.h> 146 #include <net/udp_tunnel.h> 147 #include <linux/net_namespace.h> 148 #include <linux/indirect_call_wrapper.h> 149 #include <net/devlink.h> 150 #include <linux/pm_runtime.h> 151 #include <linux/prandom.h> 152 #include <linux/once_lite.h> 153 154 #include "dev.h" 155 #include "net-sysfs.h" 156 157 158 static DEFINE_SPINLOCK(ptype_lock); 159 struct list_head ptype_base[PTYPE_HASH_SIZE] __read_mostly; 160 struct list_head ptype_all __read_mostly; /* Taps */ 161 162 static int netif_rx_internal(struct sk_buff *skb); 163 static int call_netdevice_notifiers_extack(unsigned long val, 164 struct net_device *dev, 165 struct netlink_ext_ack *extack); 166 static struct napi_struct *napi_by_id(unsigned int napi_id); 167 168 /* 169 * The @dev_base_head list is protected by @dev_base_lock and the rtnl 170 * semaphore. 171 * 172 * Pure readers hold dev_base_lock for reading, or rcu_read_lock() 173 * 174 * Writers must hold the rtnl semaphore while they loop through the 175 * dev_base_head list, and hold dev_base_lock for writing when they do the 176 * actual updates. This allows pure readers to access the list even 177 * while a writer is preparing to update it. 178 * 179 * To put it another way, dev_base_lock is held for writing only to 180 * protect against pure readers; the rtnl semaphore provides the 181 * protection against other writers. 182 * 183 * See, for example usages, register_netdevice() and 184 * unregister_netdevice(), which must be called with the rtnl 185 * semaphore held. 186 */ 187 DEFINE_RWLOCK(dev_base_lock); 188 EXPORT_SYMBOL(dev_base_lock); 189 190 static DEFINE_MUTEX(ifalias_mutex); 191 192 /* protects napi_hash addition/deletion and napi_gen_id */ 193 static DEFINE_SPINLOCK(napi_hash_lock); 194 195 static unsigned int napi_gen_id = NR_CPUS; 196 static DEFINE_READ_MOSTLY_HASHTABLE(napi_hash, 8); 197 198 static DECLARE_RWSEM(devnet_rename_sem); 199 200 static inline void dev_base_seq_inc(struct net *net) 201 { 202 while (++net->dev_base_seq == 0) 203 ; 204 } 205 206 static inline struct hlist_head *dev_name_hash(struct net *net, const char *name) 207 { 208 unsigned int hash = full_name_hash(net, name, strnlen(name, IFNAMSIZ)); 209 210 return &net->dev_name_head[hash_32(hash, NETDEV_HASHBITS)]; 211 } 212 213 static inline struct hlist_head *dev_index_hash(struct net *net, int ifindex) 214 { 215 return &net->dev_index_head[ifindex & (NETDEV_HASHENTRIES - 1)]; 216 } 217 218 static inline void rps_lock_irqsave(struct softnet_data *sd, 219 unsigned long *flags) 220 { 221 if (IS_ENABLED(CONFIG_RPS)) 222 spin_lock_irqsave(&sd->input_pkt_queue.lock, *flags); 223 else if (!IS_ENABLED(CONFIG_PREEMPT_RT)) 224 local_irq_save(*flags); 225 } 226 227 static inline void rps_lock_irq_disable(struct softnet_data *sd) 228 { 229 if (IS_ENABLED(CONFIG_RPS)) 230 spin_lock_irq(&sd->input_pkt_queue.lock); 231 else if (!IS_ENABLED(CONFIG_PREEMPT_RT)) 232 local_irq_disable(); 233 } 234 235 static inline void rps_unlock_irq_restore(struct softnet_data *sd, 236 unsigned long *flags) 237 { 238 if (IS_ENABLED(CONFIG_RPS)) 239 spin_unlock_irqrestore(&sd->input_pkt_queue.lock, *flags); 240 else if (!IS_ENABLED(CONFIG_PREEMPT_RT)) 241 local_irq_restore(*flags); 242 } 243 244 static inline void rps_unlock_irq_enable(struct softnet_data *sd) 245 { 246 if (IS_ENABLED(CONFIG_RPS)) 247 spin_unlock_irq(&sd->input_pkt_queue.lock); 248 else if (!IS_ENABLED(CONFIG_PREEMPT_RT)) 249 local_irq_enable(); 250 } 251 252 static struct netdev_name_node *netdev_name_node_alloc(struct net_device *dev, 253 const char *name) 254 { 255 struct netdev_name_node *name_node; 256 257 name_node = kmalloc(sizeof(*name_node), GFP_KERNEL); 258 if (!name_node) 259 return NULL; 260 INIT_HLIST_NODE(&name_node->hlist); 261 name_node->dev = dev; 262 name_node->name = name; 263 return name_node; 264 } 265 266 static struct netdev_name_node * 267 netdev_name_node_head_alloc(struct net_device *dev) 268 { 269 struct netdev_name_node *name_node; 270 271 name_node = netdev_name_node_alloc(dev, dev->name); 272 if (!name_node) 273 return NULL; 274 INIT_LIST_HEAD(&name_node->list); 275 return name_node; 276 } 277 278 static void netdev_name_node_free(struct netdev_name_node *name_node) 279 { 280 kfree(name_node); 281 } 282 283 static void netdev_name_node_add(struct net *net, 284 struct netdev_name_node *name_node) 285 { 286 hlist_add_head_rcu(&name_node->hlist, 287 dev_name_hash(net, name_node->name)); 288 } 289 290 static void netdev_name_node_del(struct netdev_name_node *name_node) 291 { 292 hlist_del_rcu(&name_node->hlist); 293 } 294 295 static struct netdev_name_node *netdev_name_node_lookup(struct net *net, 296 const char *name) 297 { 298 struct hlist_head *head = dev_name_hash(net, name); 299 struct netdev_name_node *name_node; 300 301 hlist_for_each_entry(name_node, head, hlist) 302 if (!strcmp(name_node->name, name)) 303 return name_node; 304 return NULL; 305 } 306 307 static struct netdev_name_node *netdev_name_node_lookup_rcu(struct net *net, 308 const char *name) 309 { 310 struct hlist_head *head = dev_name_hash(net, name); 311 struct netdev_name_node *name_node; 312 313 hlist_for_each_entry_rcu(name_node, head, hlist) 314 if (!strcmp(name_node->name, name)) 315 return name_node; 316 return NULL; 317 } 318 319 bool netdev_name_in_use(struct net *net, const char *name) 320 { 321 return netdev_name_node_lookup(net, name); 322 } 323 EXPORT_SYMBOL(netdev_name_in_use); 324 325 int netdev_name_node_alt_create(struct net_device *dev, const char *name) 326 { 327 struct netdev_name_node *name_node; 328 struct net *net = dev_net(dev); 329 330 name_node = netdev_name_node_lookup(net, name); 331 if (name_node) 332 return -EEXIST; 333 name_node = netdev_name_node_alloc(dev, name); 334 if (!name_node) 335 return -ENOMEM; 336 netdev_name_node_add(net, name_node); 337 /* The node that holds dev->name acts as a head of per-device list. */ 338 list_add_tail(&name_node->list, &dev->name_node->list); 339 340 return 0; 341 } 342 343 static void __netdev_name_node_alt_destroy(struct netdev_name_node *name_node) 344 { 345 list_del(&name_node->list); 346 netdev_name_node_del(name_node); 347 kfree(name_node->name); 348 netdev_name_node_free(name_node); 349 } 350 351 int netdev_name_node_alt_destroy(struct net_device *dev, const char *name) 352 { 353 struct netdev_name_node *name_node; 354 struct net *net = dev_net(dev); 355 356 name_node = netdev_name_node_lookup(net, name); 357 if (!name_node) 358 return -ENOENT; 359 /* lookup might have found our primary name or a name belonging 360 * to another device. 361 */ 362 if (name_node == dev->name_node || name_node->dev != dev) 363 return -EINVAL; 364 365 __netdev_name_node_alt_destroy(name_node); 366 367 return 0; 368 } 369 370 static void netdev_name_node_alt_flush(struct net_device *dev) 371 { 372 struct netdev_name_node *name_node, *tmp; 373 374 list_for_each_entry_safe(name_node, tmp, &dev->name_node->list, list) 375 __netdev_name_node_alt_destroy(name_node); 376 } 377 378 /* Device list insertion */ 379 static void list_netdevice(struct net_device *dev) 380 { 381 struct net *net = dev_net(dev); 382 383 ASSERT_RTNL(); 384 385 write_lock(&dev_base_lock); 386 list_add_tail_rcu(&dev->dev_list, &net->dev_base_head); 387 netdev_name_node_add(net, dev->name_node); 388 hlist_add_head_rcu(&dev->index_hlist, 389 dev_index_hash(net, dev->ifindex)); 390 write_unlock(&dev_base_lock); 391 392 dev_base_seq_inc(net); 393 } 394 395 /* Device list removal 396 * caller must respect a RCU grace period before freeing/reusing dev 397 */ 398 static void unlist_netdevice(struct net_device *dev, bool lock) 399 { 400 ASSERT_RTNL(); 401 402 /* Unlink dev from the device chain */ 403 if (lock) 404 write_lock(&dev_base_lock); 405 list_del_rcu(&dev->dev_list); 406 netdev_name_node_del(dev->name_node); 407 hlist_del_rcu(&dev->index_hlist); 408 if (lock) 409 write_unlock(&dev_base_lock); 410 411 dev_base_seq_inc(dev_net(dev)); 412 } 413 414 /* 415 * Our notifier list 416 */ 417 418 static RAW_NOTIFIER_HEAD(netdev_chain); 419 420 /* 421 * Device drivers call our routines to queue packets here. We empty the 422 * queue in the local softnet handler. 423 */ 424 425 DEFINE_PER_CPU_ALIGNED(struct softnet_data, softnet_data); 426 EXPORT_PER_CPU_SYMBOL(softnet_data); 427 428 #ifdef CONFIG_LOCKDEP 429 /* 430 * register_netdevice() inits txq->_xmit_lock and sets lockdep class 431 * according to dev->type 432 */ 433 static const unsigned short netdev_lock_type[] = { 434 ARPHRD_NETROM, ARPHRD_ETHER, ARPHRD_EETHER, ARPHRD_AX25, 435 ARPHRD_PRONET, ARPHRD_CHAOS, ARPHRD_IEEE802, ARPHRD_ARCNET, 436 ARPHRD_APPLETLK, ARPHRD_DLCI, ARPHRD_ATM, ARPHRD_METRICOM, 437 ARPHRD_IEEE1394, ARPHRD_EUI64, ARPHRD_INFINIBAND, ARPHRD_SLIP, 438 ARPHRD_CSLIP, ARPHRD_SLIP6, ARPHRD_CSLIP6, ARPHRD_RSRVD, 439 ARPHRD_ADAPT, ARPHRD_ROSE, ARPHRD_X25, ARPHRD_HWX25, 440 ARPHRD_PPP, ARPHRD_CISCO, ARPHRD_LAPB, ARPHRD_DDCMP, 441 ARPHRD_RAWHDLC, ARPHRD_TUNNEL, ARPHRD_TUNNEL6, ARPHRD_FRAD, 442 ARPHRD_SKIP, ARPHRD_LOOPBACK, ARPHRD_LOCALTLK, ARPHRD_FDDI, 443 ARPHRD_BIF, ARPHRD_SIT, ARPHRD_IPDDP, ARPHRD_IPGRE, 444 ARPHRD_PIMREG, ARPHRD_HIPPI, ARPHRD_ASH, ARPHRD_ECONET, 445 ARPHRD_IRDA, ARPHRD_FCPP, ARPHRD_FCAL, ARPHRD_FCPL, 446 ARPHRD_FCFABRIC, ARPHRD_IEEE80211, ARPHRD_IEEE80211_PRISM, 447 ARPHRD_IEEE80211_RADIOTAP, ARPHRD_PHONET, ARPHRD_PHONET_PIPE, 448 ARPHRD_IEEE802154, ARPHRD_VOID, ARPHRD_NONE}; 449 450 static const char *const netdev_lock_name[] = { 451 "_xmit_NETROM", "_xmit_ETHER", "_xmit_EETHER", "_xmit_AX25", 452 "_xmit_PRONET", "_xmit_CHAOS", "_xmit_IEEE802", "_xmit_ARCNET", 453 "_xmit_APPLETLK", "_xmit_DLCI", "_xmit_ATM", "_xmit_METRICOM", 454 "_xmit_IEEE1394", "_xmit_EUI64", "_xmit_INFINIBAND", "_xmit_SLIP", 455 "_xmit_CSLIP", "_xmit_SLIP6", "_xmit_CSLIP6", "_xmit_RSRVD", 456 "_xmit_ADAPT", "_xmit_ROSE", "_xmit_X25", "_xmit_HWX25", 457 "_xmit_PPP", "_xmit_CISCO", "_xmit_LAPB", "_xmit_DDCMP", 458 "_xmit_RAWHDLC", "_xmit_TUNNEL", "_xmit_TUNNEL6", "_xmit_FRAD", 459 "_xmit_SKIP", "_xmit_LOOPBACK", "_xmit_LOCALTLK", "_xmit_FDDI", 460 "_xmit_BIF", "_xmit_SIT", "_xmit_IPDDP", "_xmit_IPGRE", 461 "_xmit_PIMREG", "_xmit_HIPPI", "_xmit_ASH", "_xmit_ECONET", 462 "_xmit_IRDA", "_xmit_FCPP", "_xmit_FCAL", "_xmit_FCPL", 463 "_xmit_FCFABRIC", "_xmit_IEEE80211", "_xmit_IEEE80211_PRISM", 464 "_xmit_IEEE80211_RADIOTAP", "_xmit_PHONET", "_xmit_PHONET_PIPE", 465 "_xmit_IEEE802154", "_xmit_VOID", "_xmit_NONE"}; 466 467 static struct lock_class_key netdev_xmit_lock_key[ARRAY_SIZE(netdev_lock_type)]; 468 static struct lock_class_key netdev_addr_lock_key[ARRAY_SIZE(netdev_lock_type)]; 469 470 static inline unsigned short netdev_lock_pos(unsigned short dev_type) 471 { 472 int i; 473 474 for (i = 0; i < ARRAY_SIZE(netdev_lock_type); i++) 475 if (netdev_lock_type[i] == dev_type) 476 return i; 477 /* the last key is used by default */ 478 return ARRAY_SIZE(netdev_lock_type) - 1; 479 } 480 481 static inline void netdev_set_xmit_lockdep_class(spinlock_t *lock, 482 unsigned short dev_type) 483 { 484 int i; 485 486 i = netdev_lock_pos(dev_type); 487 lockdep_set_class_and_name(lock, &netdev_xmit_lock_key[i], 488 netdev_lock_name[i]); 489 } 490 491 static inline void netdev_set_addr_lockdep_class(struct net_device *dev) 492 { 493 int i; 494 495 i = netdev_lock_pos(dev->type); 496 lockdep_set_class_and_name(&dev->addr_list_lock, 497 &netdev_addr_lock_key[i], 498 netdev_lock_name[i]); 499 } 500 #else 501 static inline void netdev_set_xmit_lockdep_class(spinlock_t *lock, 502 unsigned short dev_type) 503 { 504 } 505 506 static inline void netdev_set_addr_lockdep_class(struct net_device *dev) 507 { 508 } 509 #endif 510 511 /******************************************************************************* 512 * 513 * Protocol management and registration routines 514 * 515 *******************************************************************************/ 516 517 518 /* 519 * Add a protocol ID to the list. Now that the input handler is 520 * smarter we can dispense with all the messy stuff that used to be 521 * here. 522 * 523 * BEWARE!!! Protocol handlers, mangling input packets, 524 * MUST BE last in hash buckets and checking protocol handlers 525 * MUST start from promiscuous ptype_all chain in net_bh. 526 * It is true now, do not change it. 527 * Explanation follows: if protocol handler, mangling packet, will 528 * be the first on list, it is not able to sense, that packet 529 * is cloned and should be copied-on-write, so that it will 530 * change it and subsequent readers will get broken packet. 531 * --ANK (980803) 532 */ 533 534 static inline struct list_head *ptype_head(const struct packet_type *pt) 535 { 536 if (pt->type == htons(ETH_P_ALL)) 537 return pt->dev ? &pt->dev->ptype_all : &ptype_all; 538 else 539 return pt->dev ? &pt->dev->ptype_specific : 540 &ptype_base[ntohs(pt->type) & PTYPE_HASH_MASK]; 541 } 542 543 /** 544 * dev_add_pack - add packet handler 545 * @pt: packet type declaration 546 * 547 * Add a protocol handler to the networking stack. The passed &packet_type 548 * is linked into kernel lists and may not be freed until it has been 549 * removed from the kernel lists. 550 * 551 * This call does not sleep therefore it can not 552 * guarantee all CPU's that are in middle of receiving packets 553 * will see the new packet type (until the next received packet). 554 */ 555 556 void dev_add_pack(struct packet_type *pt) 557 { 558 struct list_head *head = ptype_head(pt); 559 560 spin_lock(&ptype_lock); 561 list_add_rcu(&pt->list, head); 562 spin_unlock(&ptype_lock); 563 } 564 EXPORT_SYMBOL(dev_add_pack); 565 566 /** 567 * __dev_remove_pack - remove packet handler 568 * @pt: packet type declaration 569 * 570 * Remove a protocol handler that was previously added to the kernel 571 * protocol handlers by dev_add_pack(). The passed &packet_type is removed 572 * from the kernel lists and can be freed or reused once this function 573 * returns. 574 * 575 * The packet type might still be in use by receivers 576 * and must not be freed until after all the CPU's have gone 577 * through a quiescent state. 578 */ 579 void __dev_remove_pack(struct packet_type *pt) 580 { 581 struct list_head *head = ptype_head(pt); 582 struct packet_type *pt1; 583 584 spin_lock(&ptype_lock); 585 586 list_for_each_entry(pt1, head, list) { 587 if (pt == pt1) { 588 list_del_rcu(&pt->list); 589 goto out; 590 } 591 } 592 593 pr_warn("dev_remove_pack: %p not found\n", pt); 594 out: 595 spin_unlock(&ptype_lock); 596 } 597 EXPORT_SYMBOL(__dev_remove_pack); 598 599 /** 600 * dev_remove_pack - remove packet handler 601 * @pt: packet type declaration 602 * 603 * Remove a protocol handler that was previously added to the kernel 604 * protocol handlers by dev_add_pack(). The passed &packet_type is removed 605 * from the kernel lists and can be freed or reused once this function 606 * returns. 607 * 608 * This call sleeps to guarantee that no CPU is looking at the packet 609 * type after return. 610 */ 611 void dev_remove_pack(struct packet_type *pt) 612 { 613 __dev_remove_pack(pt); 614 615 synchronize_net(); 616 } 617 EXPORT_SYMBOL(dev_remove_pack); 618 619 620 /******************************************************************************* 621 * 622 * Device Interface Subroutines 623 * 624 *******************************************************************************/ 625 626 /** 627 * dev_get_iflink - get 'iflink' value of a interface 628 * @dev: targeted interface 629 * 630 * Indicates the ifindex the interface is linked to. 631 * Physical interfaces have the same 'ifindex' and 'iflink' values. 632 */ 633 634 int dev_get_iflink(const struct net_device *dev) 635 { 636 if (dev->netdev_ops && dev->netdev_ops->ndo_get_iflink) 637 return dev->netdev_ops->ndo_get_iflink(dev); 638 639 return dev->ifindex; 640 } 641 EXPORT_SYMBOL(dev_get_iflink); 642 643 /** 644 * dev_fill_metadata_dst - Retrieve tunnel egress information. 645 * @dev: targeted interface 646 * @skb: The packet. 647 * 648 * For better visibility of tunnel traffic OVS needs to retrieve 649 * egress tunnel information for a packet. Following API allows 650 * user to get this info. 651 */ 652 int dev_fill_metadata_dst(struct net_device *dev, struct sk_buff *skb) 653 { 654 struct ip_tunnel_info *info; 655 656 if (!dev->netdev_ops || !dev->netdev_ops->ndo_fill_metadata_dst) 657 return -EINVAL; 658 659 info = skb_tunnel_info_unclone(skb); 660 if (!info) 661 return -ENOMEM; 662 if (unlikely(!(info->mode & IP_TUNNEL_INFO_TX))) 663 return -EINVAL; 664 665 return dev->netdev_ops->ndo_fill_metadata_dst(dev, skb); 666 } 667 EXPORT_SYMBOL_GPL(dev_fill_metadata_dst); 668 669 static struct net_device_path *dev_fwd_path(struct net_device_path_stack *stack) 670 { 671 int k = stack->num_paths++; 672 673 if (WARN_ON_ONCE(k >= NET_DEVICE_PATH_STACK_MAX)) 674 return NULL; 675 676 return &stack->path[k]; 677 } 678 679 int dev_fill_forward_path(const struct net_device *dev, const u8 *daddr, 680 struct net_device_path_stack *stack) 681 { 682 const struct net_device *last_dev; 683 struct net_device_path_ctx ctx = { 684 .dev = dev, 685 }; 686 struct net_device_path *path; 687 int ret = 0; 688 689 memcpy(ctx.daddr, daddr, sizeof(ctx.daddr)); 690 stack->num_paths = 0; 691 while (ctx.dev && ctx.dev->netdev_ops->ndo_fill_forward_path) { 692 last_dev = ctx.dev; 693 path = dev_fwd_path(stack); 694 if (!path) 695 return -1; 696 697 memset(path, 0, sizeof(struct net_device_path)); 698 ret = ctx.dev->netdev_ops->ndo_fill_forward_path(&ctx, path); 699 if (ret < 0) 700 return -1; 701 702 if (WARN_ON_ONCE(last_dev == ctx.dev)) 703 return -1; 704 } 705 706 if (!ctx.dev) 707 return ret; 708 709 path = dev_fwd_path(stack); 710 if (!path) 711 return -1; 712 path->type = DEV_PATH_ETHERNET; 713 path->dev = ctx.dev; 714 715 return ret; 716 } 717 EXPORT_SYMBOL_GPL(dev_fill_forward_path); 718 719 /** 720 * __dev_get_by_name - find a device by its name 721 * @net: the applicable net namespace 722 * @name: name to find 723 * 724 * Find an interface by name. Must be called under RTNL semaphore 725 * or @dev_base_lock. If the name is found a pointer to the device 726 * is returned. If the name is not found then %NULL is returned. The 727 * reference counters are not incremented so the caller must be 728 * careful with locks. 729 */ 730 731 struct net_device *__dev_get_by_name(struct net *net, const char *name) 732 { 733 struct netdev_name_node *node_name; 734 735 node_name = netdev_name_node_lookup(net, name); 736 return node_name ? node_name->dev : NULL; 737 } 738 EXPORT_SYMBOL(__dev_get_by_name); 739 740 /** 741 * dev_get_by_name_rcu - find a device by its name 742 * @net: the applicable net namespace 743 * @name: name to find 744 * 745 * Find an interface by name. 746 * If the name is found a pointer to the device is returned. 747 * If the name is not found then %NULL is returned. 748 * The reference counters are not incremented so the caller must be 749 * careful with locks. The caller must hold RCU lock. 750 */ 751 752 struct net_device *dev_get_by_name_rcu(struct net *net, const char *name) 753 { 754 struct netdev_name_node *node_name; 755 756 node_name = netdev_name_node_lookup_rcu(net, name); 757 return node_name ? node_name->dev : NULL; 758 } 759 EXPORT_SYMBOL(dev_get_by_name_rcu); 760 761 /** 762 * dev_get_by_name - find a device by its name 763 * @net: the applicable net namespace 764 * @name: name to find 765 * 766 * Find an interface by name. This can be called from any 767 * context and does its own locking. The returned handle has 768 * the usage count incremented and the caller must use dev_put() to 769 * release it when it is no longer needed. %NULL is returned if no 770 * matching device is found. 771 */ 772 773 struct net_device *dev_get_by_name(struct net *net, const char *name) 774 { 775 struct net_device *dev; 776 777 rcu_read_lock(); 778 dev = dev_get_by_name_rcu(net, name); 779 dev_hold(dev); 780 rcu_read_unlock(); 781 return dev; 782 } 783 EXPORT_SYMBOL(dev_get_by_name); 784 785 /** 786 * __dev_get_by_index - find a device by its ifindex 787 * @net: the applicable net namespace 788 * @ifindex: index of device 789 * 790 * Search for an interface by index. Returns %NULL if the device 791 * is not found or a pointer to the device. The device has not 792 * had its reference counter increased so the caller must be careful 793 * about locking. The caller must hold either the RTNL semaphore 794 * or @dev_base_lock. 795 */ 796 797 struct net_device *__dev_get_by_index(struct net *net, int ifindex) 798 { 799 struct net_device *dev; 800 struct hlist_head *head = dev_index_hash(net, ifindex); 801 802 hlist_for_each_entry(dev, head, index_hlist) 803 if (dev->ifindex == ifindex) 804 return dev; 805 806 return NULL; 807 } 808 EXPORT_SYMBOL(__dev_get_by_index); 809 810 /** 811 * dev_get_by_index_rcu - find a device by its ifindex 812 * @net: the applicable net namespace 813 * @ifindex: index of device 814 * 815 * Search for an interface by index. Returns %NULL if the device 816 * is not found or a pointer to the device. The device has not 817 * had its reference counter increased so the caller must be careful 818 * about locking. The caller must hold RCU lock. 819 */ 820 821 struct net_device *dev_get_by_index_rcu(struct net *net, int ifindex) 822 { 823 struct net_device *dev; 824 struct hlist_head *head = dev_index_hash(net, ifindex); 825 826 hlist_for_each_entry_rcu(dev, head, index_hlist) 827 if (dev->ifindex == ifindex) 828 return dev; 829 830 return NULL; 831 } 832 EXPORT_SYMBOL(dev_get_by_index_rcu); 833 834 835 /** 836 * dev_get_by_index - find a device by its ifindex 837 * @net: the applicable net namespace 838 * @ifindex: index of device 839 * 840 * Search for an interface by index. Returns NULL if the device 841 * is not found or a pointer to the device. The device returned has 842 * had a reference added and the pointer is safe until the user calls 843 * dev_put to indicate they have finished with it. 844 */ 845 846 struct net_device *dev_get_by_index(struct net *net, int ifindex) 847 { 848 struct net_device *dev; 849 850 rcu_read_lock(); 851 dev = dev_get_by_index_rcu(net, ifindex); 852 dev_hold(dev); 853 rcu_read_unlock(); 854 return dev; 855 } 856 EXPORT_SYMBOL(dev_get_by_index); 857 858 /** 859 * dev_get_by_napi_id - find a device by napi_id 860 * @napi_id: ID of the NAPI struct 861 * 862 * Search for an interface by NAPI ID. Returns %NULL if the device 863 * is not found or a pointer to the device. The device has not had 864 * its reference counter increased so the caller must be careful 865 * about locking. The caller must hold RCU lock. 866 */ 867 868 struct net_device *dev_get_by_napi_id(unsigned int napi_id) 869 { 870 struct napi_struct *napi; 871 872 WARN_ON_ONCE(!rcu_read_lock_held()); 873 874 if (napi_id < MIN_NAPI_ID) 875 return NULL; 876 877 napi = napi_by_id(napi_id); 878 879 return napi ? napi->dev : NULL; 880 } 881 EXPORT_SYMBOL(dev_get_by_napi_id); 882 883 /** 884 * netdev_get_name - get a netdevice name, knowing its ifindex. 885 * @net: network namespace 886 * @name: a pointer to the buffer where the name will be stored. 887 * @ifindex: the ifindex of the interface to get the name from. 888 */ 889 int netdev_get_name(struct net *net, char *name, int ifindex) 890 { 891 struct net_device *dev; 892 int ret; 893 894 down_read(&devnet_rename_sem); 895 rcu_read_lock(); 896 897 dev = dev_get_by_index_rcu(net, ifindex); 898 if (!dev) { 899 ret = -ENODEV; 900 goto out; 901 } 902 903 strcpy(name, dev->name); 904 905 ret = 0; 906 out: 907 rcu_read_unlock(); 908 up_read(&devnet_rename_sem); 909 return ret; 910 } 911 912 /** 913 * dev_getbyhwaddr_rcu - find a device by its hardware address 914 * @net: the applicable net namespace 915 * @type: media type of device 916 * @ha: hardware address 917 * 918 * Search for an interface by MAC address. Returns NULL if the device 919 * is not found or a pointer to the device. 920 * The caller must hold RCU or RTNL. 921 * The returned device has not had its ref count increased 922 * and the caller must therefore be careful about locking 923 * 924 */ 925 926 struct net_device *dev_getbyhwaddr_rcu(struct net *net, unsigned short type, 927 const char *ha) 928 { 929 struct net_device *dev; 930 931 for_each_netdev_rcu(net, dev) 932 if (dev->type == type && 933 !memcmp(dev->dev_addr, ha, dev->addr_len)) 934 return dev; 935 936 return NULL; 937 } 938 EXPORT_SYMBOL(dev_getbyhwaddr_rcu); 939 940 struct net_device *dev_getfirstbyhwtype(struct net *net, unsigned short type) 941 { 942 struct net_device *dev, *ret = NULL; 943 944 rcu_read_lock(); 945 for_each_netdev_rcu(net, dev) 946 if (dev->type == type) { 947 dev_hold(dev); 948 ret = dev; 949 break; 950 } 951 rcu_read_unlock(); 952 return ret; 953 } 954 EXPORT_SYMBOL(dev_getfirstbyhwtype); 955 956 /** 957 * __dev_get_by_flags - find any device with given flags 958 * @net: the applicable net namespace 959 * @if_flags: IFF_* values 960 * @mask: bitmask of bits in if_flags to check 961 * 962 * Search for any interface with the given flags. Returns NULL if a device 963 * is not found or a pointer to the device. Must be called inside 964 * rtnl_lock(), and result refcount is unchanged. 965 */ 966 967 struct net_device *__dev_get_by_flags(struct net *net, unsigned short if_flags, 968 unsigned short mask) 969 { 970 struct net_device *dev, *ret; 971 972 ASSERT_RTNL(); 973 974 ret = NULL; 975 for_each_netdev(net, dev) { 976 if (((dev->flags ^ if_flags) & mask) == 0) { 977 ret = dev; 978 break; 979 } 980 } 981 return ret; 982 } 983 EXPORT_SYMBOL(__dev_get_by_flags); 984 985 /** 986 * dev_valid_name - check if name is okay for network device 987 * @name: name string 988 * 989 * Network device names need to be valid file names to 990 * allow sysfs to work. We also disallow any kind of 991 * whitespace. 992 */ 993 bool dev_valid_name(const char *name) 994 { 995 if (*name == '\0') 996 return false; 997 if (strnlen(name, IFNAMSIZ) == IFNAMSIZ) 998 return false; 999 if (!strcmp(name, ".") || !strcmp(name, "..")) 1000 return false; 1001 1002 while (*name) { 1003 if (*name == '/' || *name == ':' || isspace(*name)) 1004 return false; 1005 name++; 1006 } 1007 return true; 1008 } 1009 EXPORT_SYMBOL(dev_valid_name); 1010 1011 /** 1012 * __dev_alloc_name - allocate a name for a device 1013 * @net: network namespace to allocate the device name in 1014 * @name: name format string 1015 * @buf: scratch buffer and result name string 1016 * 1017 * Passed a format string - eg "lt%d" it will try and find a suitable 1018 * id. It scans list of devices to build up a free map, then chooses 1019 * the first empty slot. The caller must hold the dev_base or rtnl lock 1020 * while allocating the name and adding the device in order to avoid 1021 * duplicates. 1022 * Limited to bits_per_byte * page size devices (ie 32K on most platforms). 1023 * Returns the number of the unit assigned or a negative errno code. 1024 */ 1025 1026 static int __dev_alloc_name(struct net *net, const char *name, char *buf) 1027 { 1028 int i = 0; 1029 const char *p; 1030 const int max_netdevices = 8*PAGE_SIZE; 1031 unsigned long *inuse; 1032 struct net_device *d; 1033 1034 if (!dev_valid_name(name)) 1035 return -EINVAL; 1036 1037 p = strchr(name, '%'); 1038 if (p) { 1039 /* 1040 * Verify the string as this thing may have come from 1041 * the user. There must be either one "%d" and no other "%" 1042 * characters. 1043 */ 1044 if (p[1] != 'd' || strchr(p + 2, '%')) 1045 return -EINVAL; 1046 1047 /* Use one page as a bit array of possible slots */ 1048 inuse = (unsigned long *) get_zeroed_page(GFP_ATOMIC); 1049 if (!inuse) 1050 return -ENOMEM; 1051 1052 for_each_netdev(net, d) { 1053 struct netdev_name_node *name_node; 1054 list_for_each_entry(name_node, &d->name_node->list, list) { 1055 if (!sscanf(name_node->name, name, &i)) 1056 continue; 1057 if (i < 0 || i >= max_netdevices) 1058 continue; 1059 1060 /* avoid cases where sscanf is not exact inverse of printf */ 1061 snprintf(buf, IFNAMSIZ, name, i); 1062 if (!strncmp(buf, name_node->name, IFNAMSIZ)) 1063 __set_bit(i, inuse); 1064 } 1065 if (!sscanf(d->name, name, &i)) 1066 continue; 1067 if (i < 0 || i >= max_netdevices) 1068 continue; 1069 1070 /* avoid cases where sscanf is not exact inverse of printf */ 1071 snprintf(buf, IFNAMSIZ, name, i); 1072 if (!strncmp(buf, d->name, IFNAMSIZ)) 1073 __set_bit(i, inuse); 1074 } 1075 1076 i = find_first_zero_bit(inuse, max_netdevices); 1077 free_page((unsigned long) inuse); 1078 } 1079 1080 snprintf(buf, IFNAMSIZ, name, i); 1081 if (!netdev_name_in_use(net, buf)) 1082 return i; 1083 1084 /* It is possible to run out of possible slots 1085 * when the name is long and there isn't enough space left 1086 * for the digits, or if all bits are used. 1087 */ 1088 return -ENFILE; 1089 } 1090 1091 static int dev_alloc_name_ns(struct net *net, 1092 struct net_device *dev, 1093 const char *name) 1094 { 1095 char buf[IFNAMSIZ]; 1096 int ret; 1097 1098 BUG_ON(!net); 1099 ret = __dev_alloc_name(net, name, buf); 1100 if (ret >= 0) 1101 strscpy(dev->name, buf, IFNAMSIZ); 1102 return ret; 1103 } 1104 1105 /** 1106 * dev_alloc_name - allocate a name for a device 1107 * @dev: device 1108 * @name: name format string 1109 * 1110 * Passed a format string - eg "lt%d" it will try and find a suitable 1111 * id. It scans list of devices to build up a free map, then chooses 1112 * the first empty slot. The caller must hold the dev_base or rtnl lock 1113 * while allocating the name and adding the device in order to avoid 1114 * duplicates. 1115 * Limited to bits_per_byte * page size devices (ie 32K on most platforms). 1116 * Returns the number of the unit assigned or a negative errno code. 1117 */ 1118 1119 int dev_alloc_name(struct net_device *dev, const char *name) 1120 { 1121 return dev_alloc_name_ns(dev_net(dev), dev, name); 1122 } 1123 EXPORT_SYMBOL(dev_alloc_name); 1124 1125 static int dev_get_valid_name(struct net *net, struct net_device *dev, 1126 const char *name) 1127 { 1128 BUG_ON(!net); 1129 1130 if (!dev_valid_name(name)) 1131 return -EINVAL; 1132 1133 if (strchr(name, '%')) 1134 return dev_alloc_name_ns(net, dev, name); 1135 else if (netdev_name_in_use(net, name)) 1136 return -EEXIST; 1137 else if (dev->name != name) 1138 strscpy(dev->name, name, IFNAMSIZ); 1139 1140 return 0; 1141 } 1142 1143 /** 1144 * dev_change_name - change name of a device 1145 * @dev: device 1146 * @newname: name (or format string) must be at least IFNAMSIZ 1147 * 1148 * Change name of a device, can pass format strings "eth%d". 1149 * for wildcarding. 1150 */ 1151 int dev_change_name(struct net_device *dev, const char *newname) 1152 { 1153 unsigned char old_assign_type; 1154 char oldname[IFNAMSIZ]; 1155 int err = 0; 1156 int ret; 1157 struct net *net; 1158 1159 ASSERT_RTNL(); 1160 BUG_ON(!dev_net(dev)); 1161 1162 net = dev_net(dev); 1163 1164 down_write(&devnet_rename_sem); 1165 1166 if (strncmp(newname, dev->name, IFNAMSIZ) == 0) { 1167 up_write(&devnet_rename_sem); 1168 return 0; 1169 } 1170 1171 memcpy(oldname, dev->name, IFNAMSIZ); 1172 1173 err = dev_get_valid_name(net, dev, newname); 1174 if (err < 0) { 1175 up_write(&devnet_rename_sem); 1176 return err; 1177 } 1178 1179 if (oldname[0] && !strchr(oldname, '%')) 1180 netdev_info(dev, "renamed from %s%s\n", oldname, 1181 dev->flags & IFF_UP ? " (while UP)" : ""); 1182 1183 old_assign_type = dev->name_assign_type; 1184 dev->name_assign_type = NET_NAME_RENAMED; 1185 1186 rollback: 1187 ret = device_rename(&dev->dev, dev->name); 1188 if (ret) { 1189 memcpy(dev->name, oldname, IFNAMSIZ); 1190 dev->name_assign_type = old_assign_type; 1191 up_write(&devnet_rename_sem); 1192 return ret; 1193 } 1194 1195 up_write(&devnet_rename_sem); 1196 1197 netdev_adjacent_rename_links(dev, oldname); 1198 1199 write_lock(&dev_base_lock); 1200 netdev_name_node_del(dev->name_node); 1201 write_unlock(&dev_base_lock); 1202 1203 synchronize_rcu(); 1204 1205 write_lock(&dev_base_lock); 1206 netdev_name_node_add(net, dev->name_node); 1207 write_unlock(&dev_base_lock); 1208 1209 ret = call_netdevice_notifiers(NETDEV_CHANGENAME, dev); 1210 ret = notifier_to_errno(ret); 1211 1212 if (ret) { 1213 /* err >= 0 after dev_alloc_name() or stores the first errno */ 1214 if (err >= 0) { 1215 err = ret; 1216 down_write(&devnet_rename_sem); 1217 memcpy(dev->name, oldname, IFNAMSIZ); 1218 memcpy(oldname, newname, IFNAMSIZ); 1219 dev->name_assign_type = old_assign_type; 1220 old_assign_type = NET_NAME_RENAMED; 1221 goto rollback; 1222 } else { 1223 netdev_err(dev, "name change rollback failed: %d\n", 1224 ret); 1225 } 1226 } 1227 1228 return err; 1229 } 1230 1231 /** 1232 * dev_set_alias - change ifalias of a device 1233 * @dev: device 1234 * @alias: name up to IFALIASZ 1235 * @len: limit of bytes to copy from info 1236 * 1237 * Set ifalias for a device, 1238 */ 1239 int dev_set_alias(struct net_device *dev, const char *alias, size_t len) 1240 { 1241 struct dev_ifalias *new_alias = NULL; 1242 1243 if (len >= IFALIASZ) 1244 return -EINVAL; 1245 1246 if (len) { 1247 new_alias = kmalloc(sizeof(*new_alias) + len + 1, GFP_KERNEL); 1248 if (!new_alias) 1249 return -ENOMEM; 1250 1251 memcpy(new_alias->ifalias, alias, len); 1252 new_alias->ifalias[len] = 0; 1253 } 1254 1255 mutex_lock(&ifalias_mutex); 1256 new_alias = rcu_replace_pointer(dev->ifalias, new_alias, 1257 mutex_is_locked(&ifalias_mutex)); 1258 mutex_unlock(&ifalias_mutex); 1259 1260 if (new_alias) 1261 kfree_rcu(new_alias, rcuhead); 1262 1263 return len; 1264 } 1265 EXPORT_SYMBOL(dev_set_alias); 1266 1267 /** 1268 * dev_get_alias - get ifalias of a device 1269 * @dev: device 1270 * @name: buffer to store name of ifalias 1271 * @len: size of buffer 1272 * 1273 * get ifalias for a device. Caller must make sure dev cannot go 1274 * away, e.g. rcu read lock or own a reference count to device. 1275 */ 1276 int dev_get_alias(const struct net_device *dev, char *name, size_t len) 1277 { 1278 const struct dev_ifalias *alias; 1279 int ret = 0; 1280 1281 rcu_read_lock(); 1282 alias = rcu_dereference(dev->ifalias); 1283 if (alias) 1284 ret = snprintf(name, len, "%s", alias->ifalias); 1285 rcu_read_unlock(); 1286 1287 return ret; 1288 } 1289 1290 /** 1291 * netdev_features_change - device changes features 1292 * @dev: device to cause notification 1293 * 1294 * Called to indicate a device has changed features. 1295 */ 1296 void netdev_features_change(struct net_device *dev) 1297 { 1298 call_netdevice_notifiers(NETDEV_FEAT_CHANGE, dev); 1299 } 1300 EXPORT_SYMBOL(netdev_features_change); 1301 1302 /** 1303 * netdev_state_change - device changes state 1304 * @dev: device to cause notification 1305 * 1306 * Called to indicate a device has changed state. This function calls 1307 * the notifier chains for netdev_chain and sends a NEWLINK message 1308 * to the routing socket. 1309 */ 1310 void netdev_state_change(struct net_device *dev) 1311 { 1312 if (dev->flags & IFF_UP) { 1313 struct netdev_notifier_change_info change_info = { 1314 .info.dev = dev, 1315 }; 1316 1317 call_netdevice_notifiers_info(NETDEV_CHANGE, 1318 &change_info.info); 1319 rtmsg_ifinfo(RTM_NEWLINK, dev, 0, GFP_KERNEL, 0, NULL); 1320 } 1321 } 1322 EXPORT_SYMBOL(netdev_state_change); 1323 1324 /** 1325 * __netdev_notify_peers - notify network peers about existence of @dev, 1326 * to be called when rtnl lock is already held. 1327 * @dev: network device 1328 * 1329 * Generate traffic such that interested network peers are aware of 1330 * @dev, such as by generating a gratuitous ARP. This may be used when 1331 * a device wants to inform the rest of the network about some sort of 1332 * reconfiguration such as a failover event or virtual machine 1333 * migration. 1334 */ 1335 void __netdev_notify_peers(struct net_device *dev) 1336 { 1337 ASSERT_RTNL(); 1338 call_netdevice_notifiers(NETDEV_NOTIFY_PEERS, dev); 1339 call_netdevice_notifiers(NETDEV_RESEND_IGMP, dev); 1340 } 1341 EXPORT_SYMBOL(__netdev_notify_peers); 1342 1343 /** 1344 * netdev_notify_peers - notify network peers about existence of @dev 1345 * @dev: network device 1346 * 1347 * Generate traffic such that interested network peers are aware of 1348 * @dev, such as by generating a gratuitous ARP. This may be used when 1349 * a device wants to inform the rest of the network about some sort of 1350 * reconfiguration such as a failover event or virtual machine 1351 * migration. 1352 */ 1353 void netdev_notify_peers(struct net_device *dev) 1354 { 1355 rtnl_lock(); 1356 __netdev_notify_peers(dev); 1357 rtnl_unlock(); 1358 } 1359 EXPORT_SYMBOL(netdev_notify_peers); 1360 1361 static int napi_threaded_poll(void *data); 1362 1363 static int napi_kthread_create(struct napi_struct *n) 1364 { 1365 int err = 0; 1366 1367 /* Create and wake up the kthread once to put it in 1368 * TASK_INTERRUPTIBLE mode to avoid the blocked task 1369 * warning and work with loadavg. 1370 */ 1371 n->thread = kthread_run(napi_threaded_poll, n, "napi/%s-%d", 1372 n->dev->name, n->napi_id); 1373 if (IS_ERR(n->thread)) { 1374 err = PTR_ERR(n->thread); 1375 pr_err("kthread_run failed with err %d\n", err); 1376 n->thread = NULL; 1377 } 1378 1379 return err; 1380 } 1381 1382 static int __dev_open(struct net_device *dev, struct netlink_ext_ack *extack) 1383 { 1384 const struct net_device_ops *ops = dev->netdev_ops; 1385 int ret; 1386 1387 ASSERT_RTNL(); 1388 dev_addr_check(dev); 1389 1390 if (!netif_device_present(dev)) { 1391 /* may be detached because parent is runtime-suspended */ 1392 if (dev->dev.parent) 1393 pm_runtime_resume(dev->dev.parent); 1394 if (!netif_device_present(dev)) 1395 return -ENODEV; 1396 } 1397 1398 /* Block netpoll from trying to do any rx path servicing. 1399 * If we don't do this there is a chance ndo_poll_controller 1400 * or ndo_poll may be running while we open the device 1401 */ 1402 netpoll_poll_disable(dev); 1403 1404 ret = call_netdevice_notifiers_extack(NETDEV_PRE_UP, dev, extack); 1405 ret = notifier_to_errno(ret); 1406 if (ret) 1407 return ret; 1408 1409 set_bit(__LINK_STATE_START, &dev->state); 1410 1411 if (ops->ndo_validate_addr) 1412 ret = ops->ndo_validate_addr(dev); 1413 1414 if (!ret && ops->ndo_open) 1415 ret = ops->ndo_open(dev); 1416 1417 netpoll_poll_enable(dev); 1418 1419 if (ret) 1420 clear_bit(__LINK_STATE_START, &dev->state); 1421 else { 1422 dev->flags |= IFF_UP; 1423 dev_set_rx_mode(dev); 1424 dev_activate(dev); 1425 add_device_randomness(dev->dev_addr, dev->addr_len); 1426 } 1427 1428 return ret; 1429 } 1430 1431 /** 1432 * dev_open - prepare an interface for use. 1433 * @dev: device to open 1434 * @extack: netlink extended ack 1435 * 1436 * Takes a device from down to up state. The device's private open 1437 * function is invoked and then the multicast lists are loaded. Finally 1438 * the device is moved into the up state and a %NETDEV_UP message is 1439 * sent to the netdev notifier chain. 1440 * 1441 * Calling this function on an active interface is a nop. On a failure 1442 * a negative errno code is returned. 1443 */ 1444 int dev_open(struct net_device *dev, struct netlink_ext_ack *extack) 1445 { 1446 int ret; 1447 1448 if (dev->flags & IFF_UP) 1449 return 0; 1450 1451 ret = __dev_open(dev, extack); 1452 if (ret < 0) 1453 return ret; 1454 1455 rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP | IFF_RUNNING, GFP_KERNEL, 0, NULL); 1456 call_netdevice_notifiers(NETDEV_UP, dev); 1457 1458 return ret; 1459 } 1460 EXPORT_SYMBOL(dev_open); 1461 1462 static void __dev_close_many(struct list_head *head) 1463 { 1464 struct net_device *dev; 1465 1466 ASSERT_RTNL(); 1467 might_sleep(); 1468 1469 list_for_each_entry(dev, head, close_list) { 1470 /* Temporarily disable netpoll until the interface is down */ 1471 netpoll_poll_disable(dev); 1472 1473 call_netdevice_notifiers(NETDEV_GOING_DOWN, dev); 1474 1475 clear_bit(__LINK_STATE_START, &dev->state); 1476 1477 /* Synchronize to scheduled poll. We cannot touch poll list, it 1478 * can be even on different cpu. So just clear netif_running(). 1479 * 1480 * dev->stop() will invoke napi_disable() on all of it's 1481 * napi_struct instances on this device. 1482 */ 1483 smp_mb__after_atomic(); /* Commit netif_running(). */ 1484 } 1485 1486 dev_deactivate_many(head); 1487 1488 list_for_each_entry(dev, head, close_list) { 1489 const struct net_device_ops *ops = dev->netdev_ops; 1490 1491 /* 1492 * Call the device specific close. This cannot fail. 1493 * Only if device is UP 1494 * 1495 * We allow it to be called even after a DETACH hot-plug 1496 * event. 1497 */ 1498 if (ops->ndo_stop) 1499 ops->ndo_stop(dev); 1500 1501 dev->flags &= ~IFF_UP; 1502 netpoll_poll_enable(dev); 1503 } 1504 } 1505 1506 static void __dev_close(struct net_device *dev) 1507 { 1508 LIST_HEAD(single); 1509 1510 list_add(&dev->close_list, &single); 1511 __dev_close_many(&single); 1512 list_del(&single); 1513 } 1514 1515 void dev_close_many(struct list_head *head, bool unlink) 1516 { 1517 struct net_device *dev, *tmp; 1518 1519 /* Remove the devices that don't need to be closed */ 1520 list_for_each_entry_safe(dev, tmp, head, close_list) 1521 if (!(dev->flags & IFF_UP)) 1522 list_del_init(&dev->close_list); 1523 1524 __dev_close_many(head); 1525 1526 list_for_each_entry_safe(dev, tmp, head, close_list) { 1527 rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP | IFF_RUNNING, GFP_KERNEL, 0, NULL); 1528 call_netdevice_notifiers(NETDEV_DOWN, dev); 1529 if (unlink) 1530 list_del_init(&dev->close_list); 1531 } 1532 } 1533 EXPORT_SYMBOL(dev_close_many); 1534 1535 /** 1536 * dev_close - shutdown an interface. 1537 * @dev: device to shutdown 1538 * 1539 * This function moves an active device into down state. A 1540 * %NETDEV_GOING_DOWN is sent to the netdev notifier chain. The device 1541 * is then deactivated and finally a %NETDEV_DOWN is sent to the notifier 1542 * chain. 1543 */ 1544 void dev_close(struct net_device *dev) 1545 { 1546 if (dev->flags & IFF_UP) { 1547 LIST_HEAD(single); 1548 1549 list_add(&dev->close_list, &single); 1550 dev_close_many(&single, true); 1551 list_del(&single); 1552 } 1553 } 1554 EXPORT_SYMBOL(dev_close); 1555 1556 1557 /** 1558 * dev_disable_lro - disable Large Receive Offload on a device 1559 * @dev: device 1560 * 1561 * Disable Large Receive Offload (LRO) on a net device. Must be 1562 * called under RTNL. This is needed if received packets may be 1563 * forwarded to another interface. 1564 */ 1565 void dev_disable_lro(struct net_device *dev) 1566 { 1567 struct net_device *lower_dev; 1568 struct list_head *iter; 1569 1570 dev->wanted_features &= ~NETIF_F_LRO; 1571 netdev_update_features(dev); 1572 1573 if (unlikely(dev->features & NETIF_F_LRO)) 1574 netdev_WARN(dev, "failed to disable LRO!\n"); 1575 1576 netdev_for_each_lower_dev(dev, lower_dev, iter) 1577 dev_disable_lro(lower_dev); 1578 } 1579 EXPORT_SYMBOL(dev_disable_lro); 1580 1581 /** 1582 * dev_disable_gro_hw - disable HW Generic Receive Offload on a device 1583 * @dev: device 1584 * 1585 * Disable HW Generic Receive Offload (GRO_HW) on a net device. Must be 1586 * called under RTNL. This is needed if Generic XDP is installed on 1587 * the device. 1588 */ 1589 static void dev_disable_gro_hw(struct net_device *dev) 1590 { 1591 dev->wanted_features &= ~NETIF_F_GRO_HW; 1592 netdev_update_features(dev); 1593 1594 if (unlikely(dev->features & NETIF_F_GRO_HW)) 1595 netdev_WARN(dev, "failed to disable GRO_HW!\n"); 1596 } 1597 1598 const char *netdev_cmd_to_name(enum netdev_cmd cmd) 1599 { 1600 #define N(val) \ 1601 case NETDEV_##val: \ 1602 return "NETDEV_" __stringify(val); 1603 switch (cmd) { 1604 N(UP) N(DOWN) N(REBOOT) N(CHANGE) N(REGISTER) N(UNREGISTER) 1605 N(CHANGEMTU) N(CHANGEADDR) N(GOING_DOWN) N(CHANGENAME) N(FEAT_CHANGE) 1606 N(BONDING_FAILOVER) N(PRE_UP) N(PRE_TYPE_CHANGE) N(POST_TYPE_CHANGE) 1607 N(POST_INIT) N(PRE_UNINIT) N(RELEASE) N(NOTIFY_PEERS) N(JOIN) 1608 N(CHANGEUPPER) N(RESEND_IGMP) N(PRECHANGEMTU) N(CHANGEINFODATA) 1609 N(BONDING_INFO) N(PRECHANGEUPPER) N(CHANGELOWERSTATE) 1610 N(UDP_TUNNEL_PUSH_INFO) N(UDP_TUNNEL_DROP_INFO) N(CHANGE_TX_QUEUE_LEN) 1611 N(CVLAN_FILTER_PUSH_INFO) N(CVLAN_FILTER_DROP_INFO) 1612 N(SVLAN_FILTER_PUSH_INFO) N(SVLAN_FILTER_DROP_INFO) 1613 N(PRE_CHANGEADDR) N(OFFLOAD_XSTATS_ENABLE) N(OFFLOAD_XSTATS_DISABLE) 1614 N(OFFLOAD_XSTATS_REPORT_USED) N(OFFLOAD_XSTATS_REPORT_DELTA) 1615 N(XDP_FEAT_CHANGE) 1616 } 1617 #undef N 1618 return "UNKNOWN_NETDEV_EVENT"; 1619 } 1620 EXPORT_SYMBOL_GPL(netdev_cmd_to_name); 1621 1622 static int call_netdevice_notifier(struct notifier_block *nb, unsigned long val, 1623 struct net_device *dev) 1624 { 1625 struct netdev_notifier_info info = { 1626 .dev = dev, 1627 }; 1628 1629 return nb->notifier_call(nb, val, &info); 1630 } 1631 1632 static int call_netdevice_register_notifiers(struct notifier_block *nb, 1633 struct net_device *dev) 1634 { 1635 int err; 1636 1637 err = call_netdevice_notifier(nb, NETDEV_REGISTER, dev); 1638 err = notifier_to_errno(err); 1639 if (err) 1640 return err; 1641 1642 if (!(dev->flags & IFF_UP)) 1643 return 0; 1644 1645 call_netdevice_notifier(nb, NETDEV_UP, dev); 1646 return 0; 1647 } 1648 1649 static void call_netdevice_unregister_notifiers(struct notifier_block *nb, 1650 struct net_device *dev) 1651 { 1652 if (dev->flags & IFF_UP) { 1653 call_netdevice_notifier(nb, NETDEV_GOING_DOWN, 1654 dev); 1655 call_netdevice_notifier(nb, NETDEV_DOWN, dev); 1656 } 1657 call_netdevice_notifier(nb, NETDEV_UNREGISTER, dev); 1658 } 1659 1660 static int call_netdevice_register_net_notifiers(struct notifier_block *nb, 1661 struct net *net) 1662 { 1663 struct net_device *dev; 1664 int err; 1665 1666 for_each_netdev(net, dev) { 1667 err = call_netdevice_register_notifiers(nb, dev); 1668 if (err) 1669 goto rollback; 1670 } 1671 return 0; 1672 1673 rollback: 1674 for_each_netdev_continue_reverse(net, dev) 1675 call_netdevice_unregister_notifiers(nb, dev); 1676 return err; 1677 } 1678 1679 static void call_netdevice_unregister_net_notifiers(struct notifier_block *nb, 1680 struct net *net) 1681 { 1682 struct net_device *dev; 1683 1684 for_each_netdev(net, dev) 1685 call_netdevice_unregister_notifiers(nb, dev); 1686 } 1687 1688 static int dev_boot_phase = 1; 1689 1690 /** 1691 * register_netdevice_notifier - register a network notifier block 1692 * @nb: notifier 1693 * 1694 * Register a notifier to be called when network device events occur. 1695 * The notifier passed is linked into the kernel structures and must 1696 * not be reused until it has been unregistered. A negative errno code 1697 * is returned on a failure. 1698 * 1699 * When registered all registration and up events are replayed 1700 * to the new notifier to allow device to have a race free 1701 * view of the network device list. 1702 */ 1703 1704 int register_netdevice_notifier(struct notifier_block *nb) 1705 { 1706 struct net *net; 1707 int err; 1708 1709 /* Close race with setup_net() and cleanup_net() */ 1710 down_write(&pernet_ops_rwsem); 1711 rtnl_lock(); 1712 err = raw_notifier_chain_register(&netdev_chain, nb); 1713 if (err) 1714 goto unlock; 1715 if (dev_boot_phase) 1716 goto unlock; 1717 for_each_net(net) { 1718 err = call_netdevice_register_net_notifiers(nb, net); 1719 if (err) 1720 goto rollback; 1721 } 1722 1723 unlock: 1724 rtnl_unlock(); 1725 up_write(&pernet_ops_rwsem); 1726 return err; 1727 1728 rollback: 1729 for_each_net_continue_reverse(net) 1730 call_netdevice_unregister_net_notifiers(nb, net); 1731 1732 raw_notifier_chain_unregister(&netdev_chain, nb); 1733 goto unlock; 1734 } 1735 EXPORT_SYMBOL(register_netdevice_notifier); 1736 1737 /** 1738 * unregister_netdevice_notifier - unregister a network notifier block 1739 * @nb: notifier 1740 * 1741 * Unregister a notifier previously registered by 1742 * register_netdevice_notifier(). The notifier is unlinked into the 1743 * kernel structures and may then be reused. A negative errno code 1744 * is returned on a failure. 1745 * 1746 * After unregistering unregister and down device events are synthesized 1747 * for all devices on the device list to the removed notifier to remove 1748 * the need for special case cleanup code. 1749 */ 1750 1751 int unregister_netdevice_notifier(struct notifier_block *nb) 1752 { 1753 struct net *net; 1754 int err; 1755 1756 /* Close race with setup_net() and cleanup_net() */ 1757 down_write(&pernet_ops_rwsem); 1758 rtnl_lock(); 1759 err = raw_notifier_chain_unregister(&netdev_chain, nb); 1760 if (err) 1761 goto unlock; 1762 1763 for_each_net(net) 1764 call_netdevice_unregister_net_notifiers(nb, net); 1765 1766 unlock: 1767 rtnl_unlock(); 1768 up_write(&pernet_ops_rwsem); 1769 return err; 1770 } 1771 EXPORT_SYMBOL(unregister_netdevice_notifier); 1772 1773 static int __register_netdevice_notifier_net(struct net *net, 1774 struct notifier_block *nb, 1775 bool ignore_call_fail) 1776 { 1777 int err; 1778 1779 err = raw_notifier_chain_register(&net->netdev_chain, nb); 1780 if (err) 1781 return err; 1782 if (dev_boot_phase) 1783 return 0; 1784 1785 err = call_netdevice_register_net_notifiers(nb, net); 1786 if (err && !ignore_call_fail) 1787 goto chain_unregister; 1788 1789 return 0; 1790 1791 chain_unregister: 1792 raw_notifier_chain_unregister(&net->netdev_chain, nb); 1793 return err; 1794 } 1795 1796 static int __unregister_netdevice_notifier_net(struct net *net, 1797 struct notifier_block *nb) 1798 { 1799 int err; 1800 1801 err = raw_notifier_chain_unregister(&net->netdev_chain, nb); 1802 if (err) 1803 return err; 1804 1805 call_netdevice_unregister_net_notifiers(nb, net); 1806 return 0; 1807 } 1808 1809 /** 1810 * register_netdevice_notifier_net - register a per-netns network notifier block 1811 * @net: network namespace 1812 * @nb: notifier 1813 * 1814 * Register a notifier to be called when network device events occur. 1815 * The notifier passed is linked into the kernel structures and must 1816 * not be reused until it has been unregistered. A negative errno code 1817 * is returned on a failure. 1818 * 1819 * When registered all registration and up events are replayed 1820 * to the new notifier to allow device to have a race free 1821 * view of the network device list. 1822 */ 1823 1824 int register_netdevice_notifier_net(struct net *net, struct notifier_block *nb) 1825 { 1826 int err; 1827 1828 rtnl_lock(); 1829 err = __register_netdevice_notifier_net(net, nb, false); 1830 rtnl_unlock(); 1831 return err; 1832 } 1833 EXPORT_SYMBOL(register_netdevice_notifier_net); 1834 1835 /** 1836 * unregister_netdevice_notifier_net - unregister a per-netns 1837 * network notifier block 1838 * @net: network namespace 1839 * @nb: notifier 1840 * 1841 * Unregister a notifier previously registered by 1842 * register_netdevice_notifier_net(). The notifier is unlinked from the 1843 * kernel structures and may then be reused. A negative errno code 1844 * is returned on a failure. 1845 * 1846 * After unregistering unregister and down device events are synthesized 1847 * for all devices on the device list to the removed notifier to remove 1848 * the need for special case cleanup code. 1849 */ 1850 1851 int unregister_netdevice_notifier_net(struct net *net, 1852 struct notifier_block *nb) 1853 { 1854 int err; 1855 1856 rtnl_lock(); 1857 err = __unregister_netdevice_notifier_net(net, nb); 1858 rtnl_unlock(); 1859 return err; 1860 } 1861 EXPORT_SYMBOL(unregister_netdevice_notifier_net); 1862 1863 static void __move_netdevice_notifier_net(struct net *src_net, 1864 struct net *dst_net, 1865 struct notifier_block *nb) 1866 { 1867 __unregister_netdevice_notifier_net(src_net, nb); 1868 __register_netdevice_notifier_net(dst_net, nb, true); 1869 } 1870 1871 int register_netdevice_notifier_dev_net(struct net_device *dev, 1872 struct notifier_block *nb, 1873 struct netdev_net_notifier *nn) 1874 { 1875 int err; 1876 1877 rtnl_lock(); 1878 err = __register_netdevice_notifier_net(dev_net(dev), nb, false); 1879 if (!err) { 1880 nn->nb = nb; 1881 list_add(&nn->list, &dev->net_notifier_list); 1882 } 1883 rtnl_unlock(); 1884 return err; 1885 } 1886 EXPORT_SYMBOL(register_netdevice_notifier_dev_net); 1887 1888 int unregister_netdevice_notifier_dev_net(struct net_device *dev, 1889 struct notifier_block *nb, 1890 struct netdev_net_notifier *nn) 1891 { 1892 int err; 1893 1894 rtnl_lock(); 1895 list_del(&nn->list); 1896 err = __unregister_netdevice_notifier_net(dev_net(dev), nb); 1897 rtnl_unlock(); 1898 return err; 1899 } 1900 EXPORT_SYMBOL(unregister_netdevice_notifier_dev_net); 1901 1902 static void move_netdevice_notifiers_dev_net(struct net_device *dev, 1903 struct net *net) 1904 { 1905 struct netdev_net_notifier *nn; 1906 1907 list_for_each_entry(nn, &dev->net_notifier_list, list) 1908 __move_netdevice_notifier_net(dev_net(dev), net, nn->nb); 1909 } 1910 1911 /** 1912 * call_netdevice_notifiers_info - call all network notifier blocks 1913 * @val: value passed unmodified to notifier function 1914 * @info: notifier information data 1915 * 1916 * Call all network notifier blocks. Parameters and return value 1917 * are as for raw_notifier_call_chain(). 1918 */ 1919 1920 int call_netdevice_notifiers_info(unsigned long val, 1921 struct netdev_notifier_info *info) 1922 { 1923 struct net *net = dev_net(info->dev); 1924 int ret; 1925 1926 ASSERT_RTNL(); 1927 1928 /* Run per-netns notifier block chain first, then run the global one. 1929 * Hopefully, one day, the global one is going to be removed after 1930 * all notifier block registrators get converted to be per-netns. 1931 */ 1932 ret = raw_notifier_call_chain(&net->netdev_chain, val, info); 1933 if (ret & NOTIFY_STOP_MASK) 1934 return ret; 1935 return raw_notifier_call_chain(&netdev_chain, val, info); 1936 } 1937 1938 /** 1939 * call_netdevice_notifiers_info_robust - call per-netns notifier blocks 1940 * for and rollback on error 1941 * @val_up: value passed unmodified to notifier function 1942 * @val_down: value passed unmodified to the notifier function when 1943 * recovering from an error on @val_up 1944 * @info: notifier information data 1945 * 1946 * Call all per-netns network notifier blocks, but not notifier blocks on 1947 * the global notifier chain. Parameters and return value are as for 1948 * raw_notifier_call_chain_robust(). 1949 */ 1950 1951 static int 1952 call_netdevice_notifiers_info_robust(unsigned long val_up, 1953 unsigned long val_down, 1954 struct netdev_notifier_info *info) 1955 { 1956 struct net *net = dev_net(info->dev); 1957 1958 ASSERT_RTNL(); 1959 1960 return raw_notifier_call_chain_robust(&net->netdev_chain, 1961 val_up, val_down, info); 1962 } 1963 1964 static int call_netdevice_notifiers_extack(unsigned long val, 1965 struct net_device *dev, 1966 struct netlink_ext_ack *extack) 1967 { 1968 struct netdev_notifier_info info = { 1969 .dev = dev, 1970 .extack = extack, 1971 }; 1972 1973 return call_netdevice_notifiers_info(val, &info); 1974 } 1975 1976 /** 1977 * call_netdevice_notifiers - call all network notifier blocks 1978 * @val: value passed unmodified to notifier function 1979 * @dev: net_device pointer passed unmodified to notifier function 1980 * 1981 * Call all network notifier blocks. Parameters and return value 1982 * are as for raw_notifier_call_chain(). 1983 */ 1984 1985 int call_netdevice_notifiers(unsigned long val, struct net_device *dev) 1986 { 1987 return call_netdevice_notifiers_extack(val, dev, NULL); 1988 } 1989 EXPORT_SYMBOL(call_netdevice_notifiers); 1990 1991 /** 1992 * call_netdevice_notifiers_mtu - call all network notifier blocks 1993 * @val: value passed unmodified to notifier function 1994 * @dev: net_device pointer passed unmodified to notifier function 1995 * @arg: additional u32 argument passed to the notifier function 1996 * 1997 * Call all network notifier blocks. Parameters and return value 1998 * are as for raw_notifier_call_chain(). 1999 */ 2000 static int call_netdevice_notifiers_mtu(unsigned long val, 2001 struct net_device *dev, u32 arg) 2002 { 2003 struct netdev_notifier_info_ext info = { 2004 .info.dev = dev, 2005 .ext.mtu = arg, 2006 }; 2007 2008 BUILD_BUG_ON(offsetof(struct netdev_notifier_info_ext, info) != 0); 2009 2010 return call_netdevice_notifiers_info(val, &info.info); 2011 } 2012 2013 #ifdef CONFIG_NET_INGRESS 2014 static DEFINE_STATIC_KEY_FALSE(ingress_needed_key); 2015 2016 void net_inc_ingress_queue(void) 2017 { 2018 static_branch_inc(&ingress_needed_key); 2019 } 2020 EXPORT_SYMBOL_GPL(net_inc_ingress_queue); 2021 2022 void net_dec_ingress_queue(void) 2023 { 2024 static_branch_dec(&ingress_needed_key); 2025 } 2026 EXPORT_SYMBOL_GPL(net_dec_ingress_queue); 2027 #endif 2028 2029 #ifdef CONFIG_NET_EGRESS 2030 static DEFINE_STATIC_KEY_FALSE(egress_needed_key); 2031 2032 void net_inc_egress_queue(void) 2033 { 2034 static_branch_inc(&egress_needed_key); 2035 } 2036 EXPORT_SYMBOL_GPL(net_inc_egress_queue); 2037 2038 void net_dec_egress_queue(void) 2039 { 2040 static_branch_dec(&egress_needed_key); 2041 } 2042 EXPORT_SYMBOL_GPL(net_dec_egress_queue); 2043 #endif 2044 2045 DEFINE_STATIC_KEY_FALSE(netstamp_needed_key); 2046 EXPORT_SYMBOL(netstamp_needed_key); 2047 #ifdef CONFIG_JUMP_LABEL 2048 static atomic_t netstamp_needed_deferred; 2049 static atomic_t netstamp_wanted; 2050 static void netstamp_clear(struct work_struct *work) 2051 { 2052 int deferred = atomic_xchg(&netstamp_needed_deferred, 0); 2053 int wanted; 2054 2055 wanted = atomic_add_return(deferred, &netstamp_wanted); 2056 if (wanted > 0) 2057 static_branch_enable(&netstamp_needed_key); 2058 else 2059 static_branch_disable(&netstamp_needed_key); 2060 } 2061 static DECLARE_WORK(netstamp_work, netstamp_clear); 2062 #endif 2063 2064 void net_enable_timestamp(void) 2065 { 2066 #ifdef CONFIG_JUMP_LABEL 2067 int wanted = atomic_read(&netstamp_wanted); 2068 2069 while (wanted > 0) { 2070 if (atomic_try_cmpxchg(&netstamp_wanted, &wanted, wanted + 1)) 2071 return; 2072 } 2073 atomic_inc(&netstamp_needed_deferred); 2074 schedule_work(&netstamp_work); 2075 #else 2076 static_branch_inc(&netstamp_needed_key); 2077 #endif 2078 } 2079 EXPORT_SYMBOL(net_enable_timestamp); 2080 2081 void net_disable_timestamp(void) 2082 { 2083 #ifdef CONFIG_JUMP_LABEL 2084 int wanted = atomic_read(&netstamp_wanted); 2085 2086 while (wanted > 1) { 2087 if (atomic_try_cmpxchg(&netstamp_wanted, &wanted, wanted - 1)) 2088 return; 2089 } 2090 atomic_dec(&netstamp_needed_deferred); 2091 schedule_work(&netstamp_work); 2092 #else 2093 static_branch_dec(&netstamp_needed_key); 2094 #endif 2095 } 2096 EXPORT_SYMBOL(net_disable_timestamp); 2097 2098 static inline void net_timestamp_set(struct sk_buff *skb) 2099 { 2100 skb->tstamp = 0; 2101 skb->mono_delivery_time = 0; 2102 if (static_branch_unlikely(&netstamp_needed_key)) 2103 skb->tstamp = ktime_get_real(); 2104 } 2105 2106 #define net_timestamp_check(COND, SKB) \ 2107 if (static_branch_unlikely(&netstamp_needed_key)) { \ 2108 if ((COND) && !(SKB)->tstamp) \ 2109 (SKB)->tstamp = ktime_get_real(); \ 2110 } \ 2111 2112 bool is_skb_forwardable(const struct net_device *dev, const struct sk_buff *skb) 2113 { 2114 return __is_skb_forwardable(dev, skb, true); 2115 } 2116 EXPORT_SYMBOL_GPL(is_skb_forwardable); 2117 2118 static int __dev_forward_skb2(struct net_device *dev, struct sk_buff *skb, 2119 bool check_mtu) 2120 { 2121 int ret = ____dev_forward_skb(dev, skb, check_mtu); 2122 2123 if (likely(!ret)) { 2124 skb->protocol = eth_type_trans(skb, dev); 2125 skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN); 2126 } 2127 2128 return ret; 2129 } 2130 2131 int __dev_forward_skb(struct net_device *dev, struct sk_buff *skb) 2132 { 2133 return __dev_forward_skb2(dev, skb, true); 2134 } 2135 EXPORT_SYMBOL_GPL(__dev_forward_skb); 2136 2137 /** 2138 * dev_forward_skb - loopback an skb to another netif 2139 * 2140 * @dev: destination network device 2141 * @skb: buffer to forward 2142 * 2143 * return values: 2144 * NET_RX_SUCCESS (no congestion) 2145 * NET_RX_DROP (packet was dropped, but freed) 2146 * 2147 * dev_forward_skb can be used for injecting an skb from the 2148 * start_xmit function of one device into the receive queue 2149 * of another device. 2150 * 2151 * The receiving device may be in another namespace, so 2152 * we have to clear all information in the skb that could 2153 * impact namespace isolation. 2154 */ 2155 int dev_forward_skb(struct net_device *dev, struct sk_buff *skb) 2156 { 2157 return __dev_forward_skb(dev, skb) ?: netif_rx_internal(skb); 2158 } 2159 EXPORT_SYMBOL_GPL(dev_forward_skb); 2160 2161 int dev_forward_skb_nomtu(struct net_device *dev, struct sk_buff *skb) 2162 { 2163 return __dev_forward_skb2(dev, skb, false) ?: netif_rx_internal(skb); 2164 } 2165 2166 static inline int deliver_skb(struct sk_buff *skb, 2167 struct packet_type *pt_prev, 2168 struct net_device *orig_dev) 2169 { 2170 if (unlikely(skb_orphan_frags_rx(skb, GFP_ATOMIC))) 2171 return -ENOMEM; 2172 refcount_inc(&skb->users); 2173 return pt_prev->func(skb, skb->dev, pt_prev, orig_dev); 2174 } 2175 2176 static inline void deliver_ptype_list_skb(struct sk_buff *skb, 2177 struct packet_type **pt, 2178 struct net_device *orig_dev, 2179 __be16 type, 2180 struct list_head *ptype_list) 2181 { 2182 struct packet_type *ptype, *pt_prev = *pt; 2183 2184 list_for_each_entry_rcu(ptype, ptype_list, list) { 2185 if (ptype->type != type) 2186 continue; 2187 if (pt_prev) 2188 deliver_skb(skb, pt_prev, orig_dev); 2189 pt_prev = ptype; 2190 } 2191 *pt = pt_prev; 2192 } 2193 2194 static inline bool skb_loop_sk(struct packet_type *ptype, struct sk_buff *skb) 2195 { 2196 if (!ptype->af_packet_priv || !skb->sk) 2197 return false; 2198 2199 if (ptype->id_match) 2200 return ptype->id_match(ptype, skb->sk); 2201 else if ((struct sock *)ptype->af_packet_priv == skb->sk) 2202 return true; 2203 2204 return false; 2205 } 2206 2207 /** 2208 * dev_nit_active - return true if any network interface taps are in use 2209 * 2210 * @dev: network device to check for the presence of taps 2211 */ 2212 bool dev_nit_active(struct net_device *dev) 2213 { 2214 return !list_empty(&ptype_all) || !list_empty(&dev->ptype_all); 2215 } 2216 EXPORT_SYMBOL_GPL(dev_nit_active); 2217 2218 /* 2219 * Support routine. Sends outgoing frames to any network 2220 * taps currently in use. 2221 */ 2222 2223 void dev_queue_xmit_nit(struct sk_buff *skb, struct net_device *dev) 2224 { 2225 struct packet_type *ptype; 2226 struct sk_buff *skb2 = NULL; 2227 struct packet_type *pt_prev = NULL; 2228 struct list_head *ptype_list = &ptype_all; 2229 2230 rcu_read_lock(); 2231 again: 2232 list_for_each_entry_rcu(ptype, ptype_list, list) { 2233 if (ptype->ignore_outgoing) 2234 continue; 2235 2236 /* Never send packets back to the socket 2237 * they originated from - MvS (miquels@drinkel.ow.org) 2238 */ 2239 if (skb_loop_sk(ptype, skb)) 2240 continue; 2241 2242 if (pt_prev) { 2243 deliver_skb(skb2, pt_prev, skb->dev); 2244 pt_prev = ptype; 2245 continue; 2246 } 2247 2248 /* need to clone skb, done only once */ 2249 skb2 = skb_clone(skb, GFP_ATOMIC); 2250 if (!skb2) 2251 goto out_unlock; 2252 2253 net_timestamp_set(skb2); 2254 2255 /* skb->nh should be correctly 2256 * set by sender, so that the second statement is 2257 * just protection against buggy protocols. 2258 */ 2259 skb_reset_mac_header(skb2); 2260 2261 if (skb_network_header(skb2) < skb2->data || 2262 skb_network_header(skb2) > skb_tail_pointer(skb2)) { 2263 net_crit_ratelimited("protocol %04x is buggy, dev %s\n", 2264 ntohs(skb2->protocol), 2265 dev->name); 2266 skb_reset_network_header(skb2); 2267 } 2268 2269 skb2->transport_header = skb2->network_header; 2270 skb2->pkt_type = PACKET_OUTGOING; 2271 pt_prev = ptype; 2272 } 2273 2274 if (ptype_list == &ptype_all) { 2275 ptype_list = &dev->ptype_all; 2276 goto again; 2277 } 2278 out_unlock: 2279 if (pt_prev) { 2280 if (!skb_orphan_frags_rx(skb2, GFP_ATOMIC)) 2281 pt_prev->func(skb2, skb->dev, pt_prev, skb->dev); 2282 else 2283 kfree_skb(skb2); 2284 } 2285 rcu_read_unlock(); 2286 } 2287 EXPORT_SYMBOL_GPL(dev_queue_xmit_nit); 2288 2289 /** 2290 * netif_setup_tc - Handle tc mappings on real_num_tx_queues change 2291 * @dev: Network device 2292 * @txq: number of queues available 2293 * 2294 * If real_num_tx_queues is changed the tc mappings may no longer be 2295 * valid. To resolve this verify the tc mapping remains valid and if 2296 * not NULL the mapping. With no priorities mapping to this 2297 * offset/count pair it will no longer be used. In the worst case TC0 2298 * is invalid nothing can be done so disable priority mappings. If is 2299 * expected that drivers will fix this mapping if they can before 2300 * calling netif_set_real_num_tx_queues. 2301 */ 2302 static void netif_setup_tc(struct net_device *dev, unsigned int txq) 2303 { 2304 int i; 2305 struct netdev_tc_txq *tc = &dev->tc_to_txq[0]; 2306 2307 /* If TC0 is invalidated disable TC mapping */ 2308 if (tc->offset + tc->count > txq) { 2309 netdev_warn(dev, "Number of in use tx queues changed invalidating tc mappings. Priority traffic classification disabled!\n"); 2310 dev->num_tc = 0; 2311 return; 2312 } 2313 2314 /* Invalidated prio to tc mappings set to TC0 */ 2315 for (i = 1; i < TC_BITMASK + 1; i++) { 2316 int q = netdev_get_prio_tc_map(dev, i); 2317 2318 tc = &dev->tc_to_txq[q]; 2319 if (tc->offset + tc->count > txq) { 2320 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", 2321 i, q); 2322 netdev_set_prio_tc_map(dev, i, 0); 2323 } 2324 } 2325 } 2326 2327 int netdev_txq_to_tc(struct net_device *dev, unsigned int txq) 2328 { 2329 if (dev->num_tc) { 2330 struct netdev_tc_txq *tc = &dev->tc_to_txq[0]; 2331 int i; 2332 2333 /* walk through the TCs and see if it falls into any of them */ 2334 for (i = 0; i < TC_MAX_QUEUE; i++, tc++) { 2335 if ((txq - tc->offset) < tc->count) 2336 return i; 2337 } 2338 2339 /* didn't find it, just return -1 to indicate no match */ 2340 return -1; 2341 } 2342 2343 return 0; 2344 } 2345 EXPORT_SYMBOL(netdev_txq_to_tc); 2346 2347 #ifdef CONFIG_XPS 2348 static struct static_key xps_needed __read_mostly; 2349 static struct static_key xps_rxqs_needed __read_mostly; 2350 static DEFINE_MUTEX(xps_map_mutex); 2351 #define xmap_dereference(P) \ 2352 rcu_dereference_protected((P), lockdep_is_held(&xps_map_mutex)) 2353 2354 static bool remove_xps_queue(struct xps_dev_maps *dev_maps, 2355 struct xps_dev_maps *old_maps, int tci, u16 index) 2356 { 2357 struct xps_map *map = NULL; 2358 int pos; 2359 2360 if (dev_maps) 2361 map = xmap_dereference(dev_maps->attr_map[tci]); 2362 if (!map) 2363 return false; 2364 2365 for (pos = map->len; pos--;) { 2366 if (map->queues[pos] != index) 2367 continue; 2368 2369 if (map->len > 1) { 2370 map->queues[pos] = map->queues[--map->len]; 2371 break; 2372 } 2373 2374 if (old_maps) 2375 RCU_INIT_POINTER(old_maps->attr_map[tci], NULL); 2376 RCU_INIT_POINTER(dev_maps->attr_map[tci], NULL); 2377 kfree_rcu(map, rcu); 2378 return false; 2379 } 2380 2381 return true; 2382 } 2383 2384 static bool remove_xps_queue_cpu(struct net_device *dev, 2385 struct xps_dev_maps *dev_maps, 2386 int cpu, u16 offset, u16 count) 2387 { 2388 int num_tc = dev_maps->num_tc; 2389 bool active = false; 2390 int tci; 2391 2392 for (tci = cpu * num_tc; num_tc--; tci++) { 2393 int i, j; 2394 2395 for (i = count, j = offset; i--; j++) { 2396 if (!remove_xps_queue(dev_maps, NULL, tci, j)) 2397 break; 2398 } 2399 2400 active |= i < 0; 2401 } 2402 2403 return active; 2404 } 2405 2406 static void reset_xps_maps(struct net_device *dev, 2407 struct xps_dev_maps *dev_maps, 2408 enum xps_map_type type) 2409 { 2410 static_key_slow_dec_cpuslocked(&xps_needed); 2411 if (type == XPS_RXQS) 2412 static_key_slow_dec_cpuslocked(&xps_rxqs_needed); 2413 2414 RCU_INIT_POINTER(dev->xps_maps[type], NULL); 2415 2416 kfree_rcu(dev_maps, rcu); 2417 } 2418 2419 static void clean_xps_maps(struct net_device *dev, enum xps_map_type type, 2420 u16 offset, u16 count) 2421 { 2422 struct xps_dev_maps *dev_maps; 2423 bool active = false; 2424 int i, j; 2425 2426 dev_maps = xmap_dereference(dev->xps_maps[type]); 2427 if (!dev_maps) 2428 return; 2429 2430 for (j = 0; j < dev_maps->nr_ids; j++) 2431 active |= remove_xps_queue_cpu(dev, dev_maps, j, offset, count); 2432 if (!active) 2433 reset_xps_maps(dev, dev_maps, type); 2434 2435 if (type == XPS_CPUS) { 2436 for (i = offset + (count - 1); count--; i--) 2437 netdev_queue_numa_node_write( 2438 netdev_get_tx_queue(dev, i), NUMA_NO_NODE); 2439 } 2440 } 2441 2442 static void netif_reset_xps_queues(struct net_device *dev, u16 offset, 2443 u16 count) 2444 { 2445 if (!static_key_false(&xps_needed)) 2446 return; 2447 2448 cpus_read_lock(); 2449 mutex_lock(&xps_map_mutex); 2450 2451 if (static_key_false(&xps_rxqs_needed)) 2452 clean_xps_maps(dev, XPS_RXQS, offset, count); 2453 2454 clean_xps_maps(dev, XPS_CPUS, offset, count); 2455 2456 mutex_unlock(&xps_map_mutex); 2457 cpus_read_unlock(); 2458 } 2459 2460 static void netif_reset_xps_queues_gt(struct net_device *dev, u16 index) 2461 { 2462 netif_reset_xps_queues(dev, index, dev->num_tx_queues - index); 2463 } 2464 2465 static struct xps_map *expand_xps_map(struct xps_map *map, int attr_index, 2466 u16 index, bool is_rxqs_map) 2467 { 2468 struct xps_map *new_map; 2469 int alloc_len = XPS_MIN_MAP_ALLOC; 2470 int i, pos; 2471 2472 for (pos = 0; map && pos < map->len; pos++) { 2473 if (map->queues[pos] != index) 2474 continue; 2475 return map; 2476 } 2477 2478 /* Need to add tx-queue to this CPU's/rx-queue's existing map */ 2479 if (map) { 2480 if (pos < map->alloc_len) 2481 return map; 2482 2483 alloc_len = map->alloc_len * 2; 2484 } 2485 2486 /* Need to allocate new map to store tx-queue on this CPU's/rx-queue's 2487 * map 2488 */ 2489 if (is_rxqs_map) 2490 new_map = kzalloc(XPS_MAP_SIZE(alloc_len), GFP_KERNEL); 2491 else 2492 new_map = kzalloc_node(XPS_MAP_SIZE(alloc_len), GFP_KERNEL, 2493 cpu_to_node(attr_index)); 2494 if (!new_map) 2495 return NULL; 2496 2497 for (i = 0; i < pos; i++) 2498 new_map->queues[i] = map->queues[i]; 2499 new_map->alloc_len = alloc_len; 2500 new_map->len = pos; 2501 2502 return new_map; 2503 } 2504 2505 /* Copy xps maps at a given index */ 2506 static void xps_copy_dev_maps(struct xps_dev_maps *dev_maps, 2507 struct xps_dev_maps *new_dev_maps, int index, 2508 int tc, bool skip_tc) 2509 { 2510 int i, tci = index * dev_maps->num_tc; 2511 struct xps_map *map; 2512 2513 /* copy maps belonging to foreign traffic classes */ 2514 for (i = 0; i < dev_maps->num_tc; i++, tci++) { 2515 if (i == tc && skip_tc) 2516 continue; 2517 2518 /* fill in the new device map from the old device map */ 2519 map = xmap_dereference(dev_maps->attr_map[tci]); 2520 RCU_INIT_POINTER(new_dev_maps->attr_map[tci], map); 2521 } 2522 } 2523 2524 /* Must be called under cpus_read_lock */ 2525 int __netif_set_xps_queue(struct net_device *dev, const unsigned long *mask, 2526 u16 index, enum xps_map_type type) 2527 { 2528 struct xps_dev_maps *dev_maps, *new_dev_maps = NULL, *old_dev_maps = NULL; 2529 const unsigned long *online_mask = NULL; 2530 bool active = false, copy = false; 2531 int i, j, tci, numa_node_id = -2; 2532 int maps_sz, num_tc = 1, tc = 0; 2533 struct xps_map *map, *new_map; 2534 unsigned int nr_ids; 2535 2536 WARN_ON_ONCE(index >= dev->num_tx_queues); 2537 2538 if (dev->num_tc) { 2539 /* Do not allow XPS on subordinate device directly */ 2540 num_tc = dev->num_tc; 2541 if (num_tc < 0) 2542 return -EINVAL; 2543 2544 /* If queue belongs to subordinate dev use its map */ 2545 dev = netdev_get_tx_queue(dev, index)->sb_dev ? : dev; 2546 2547 tc = netdev_txq_to_tc(dev, index); 2548 if (tc < 0) 2549 return -EINVAL; 2550 } 2551 2552 mutex_lock(&xps_map_mutex); 2553 2554 dev_maps = xmap_dereference(dev->xps_maps[type]); 2555 if (type == XPS_RXQS) { 2556 maps_sz = XPS_RXQ_DEV_MAPS_SIZE(num_tc, dev->num_rx_queues); 2557 nr_ids = dev->num_rx_queues; 2558 } else { 2559 maps_sz = XPS_CPU_DEV_MAPS_SIZE(num_tc); 2560 if (num_possible_cpus() > 1) 2561 online_mask = cpumask_bits(cpu_online_mask); 2562 nr_ids = nr_cpu_ids; 2563 } 2564 2565 if (maps_sz < L1_CACHE_BYTES) 2566 maps_sz = L1_CACHE_BYTES; 2567 2568 /* The old dev_maps could be larger or smaller than the one we're 2569 * setting up now, as dev->num_tc or nr_ids could have been updated in 2570 * between. We could try to be smart, but let's be safe instead and only 2571 * copy foreign traffic classes if the two map sizes match. 2572 */ 2573 if (dev_maps && 2574 dev_maps->num_tc == num_tc && dev_maps->nr_ids == nr_ids) 2575 copy = true; 2576 2577 /* allocate memory for queue storage */ 2578 for (j = -1; j = netif_attrmask_next_and(j, online_mask, mask, nr_ids), 2579 j < nr_ids;) { 2580 if (!new_dev_maps) { 2581 new_dev_maps = kzalloc(maps_sz, GFP_KERNEL); 2582 if (!new_dev_maps) { 2583 mutex_unlock(&xps_map_mutex); 2584 return -ENOMEM; 2585 } 2586 2587 new_dev_maps->nr_ids = nr_ids; 2588 new_dev_maps->num_tc = num_tc; 2589 } 2590 2591 tci = j * num_tc + tc; 2592 map = copy ? xmap_dereference(dev_maps->attr_map[tci]) : NULL; 2593 2594 map = expand_xps_map(map, j, index, type == XPS_RXQS); 2595 if (!map) 2596 goto error; 2597 2598 RCU_INIT_POINTER(new_dev_maps->attr_map[tci], map); 2599 } 2600 2601 if (!new_dev_maps) 2602 goto out_no_new_maps; 2603 2604 if (!dev_maps) { 2605 /* Increment static keys at most once per type */ 2606 static_key_slow_inc_cpuslocked(&xps_needed); 2607 if (type == XPS_RXQS) 2608 static_key_slow_inc_cpuslocked(&xps_rxqs_needed); 2609 } 2610 2611 for (j = 0; j < nr_ids; j++) { 2612 bool skip_tc = false; 2613 2614 tci = j * num_tc + tc; 2615 if (netif_attr_test_mask(j, mask, nr_ids) && 2616 netif_attr_test_online(j, online_mask, nr_ids)) { 2617 /* add tx-queue to CPU/rx-queue maps */ 2618 int pos = 0; 2619 2620 skip_tc = true; 2621 2622 map = xmap_dereference(new_dev_maps->attr_map[tci]); 2623 while ((pos < map->len) && (map->queues[pos] != index)) 2624 pos++; 2625 2626 if (pos == map->len) 2627 map->queues[map->len++] = index; 2628 #ifdef CONFIG_NUMA 2629 if (type == XPS_CPUS) { 2630 if (numa_node_id == -2) 2631 numa_node_id = cpu_to_node(j); 2632 else if (numa_node_id != cpu_to_node(j)) 2633 numa_node_id = -1; 2634 } 2635 #endif 2636 } 2637 2638 if (copy) 2639 xps_copy_dev_maps(dev_maps, new_dev_maps, j, tc, 2640 skip_tc); 2641 } 2642 2643 rcu_assign_pointer(dev->xps_maps[type], new_dev_maps); 2644 2645 /* Cleanup old maps */ 2646 if (!dev_maps) 2647 goto out_no_old_maps; 2648 2649 for (j = 0; j < dev_maps->nr_ids; j++) { 2650 for (i = num_tc, tci = j * dev_maps->num_tc; i--; tci++) { 2651 map = xmap_dereference(dev_maps->attr_map[tci]); 2652 if (!map) 2653 continue; 2654 2655 if (copy) { 2656 new_map = xmap_dereference(new_dev_maps->attr_map[tci]); 2657 if (map == new_map) 2658 continue; 2659 } 2660 2661 RCU_INIT_POINTER(dev_maps->attr_map[tci], NULL); 2662 kfree_rcu(map, rcu); 2663 } 2664 } 2665 2666 old_dev_maps = dev_maps; 2667 2668 out_no_old_maps: 2669 dev_maps = new_dev_maps; 2670 active = true; 2671 2672 out_no_new_maps: 2673 if (type == XPS_CPUS) 2674 /* update Tx queue numa node */ 2675 netdev_queue_numa_node_write(netdev_get_tx_queue(dev, index), 2676 (numa_node_id >= 0) ? 2677 numa_node_id : NUMA_NO_NODE); 2678 2679 if (!dev_maps) 2680 goto out_no_maps; 2681 2682 /* removes tx-queue from unused CPUs/rx-queues */ 2683 for (j = 0; j < dev_maps->nr_ids; j++) { 2684 tci = j * dev_maps->num_tc; 2685 2686 for (i = 0; i < dev_maps->num_tc; i++, tci++) { 2687 if (i == tc && 2688 netif_attr_test_mask(j, mask, dev_maps->nr_ids) && 2689 netif_attr_test_online(j, online_mask, dev_maps->nr_ids)) 2690 continue; 2691 2692 active |= remove_xps_queue(dev_maps, 2693 copy ? old_dev_maps : NULL, 2694 tci, index); 2695 } 2696 } 2697 2698 if (old_dev_maps) 2699 kfree_rcu(old_dev_maps, rcu); 2700 2701 /* free map if not active */ 2702 if (!active) 2703 reset_xps_maps(dev, dev_maps, type); 2704 2705 out_no_maps: 2706 mutex_unlock(&xps_map_mutex); 2707 2708 return 0; 2709 error: 2710 /* remove any maps that we added */ 2711 for (j = 0; j < nr_ids; j++) { 2712 for (i = num_tc, tci = j * num_tc; i--; tci++) { 2713 new_map = xmap_dereference(new_dev_maps->attr_map[tci]); 2714 map = copy ? 2715 xmap_dereference(dev_maps->attr_map[tci]) : 2716 NULL; 2717 if (new_map && new_map != map) 2718 kfree(new_map); 2719 } 2720 } 2721 2722 mutex_unlock(&xps_map_mutex); 2723 2724 kfree(new_dev_maps); 2725 return -ENOMEM; 2726 } 2727 EXPORT_SYMBOL_GPL(__netif_set_xps_queue); 2728 2729 int netif_set_xps_queue(struct net_device *dev, const struct cpumask *mask, 2730 u16 index) 2731 { 2732 int ret; 2733 2734 cpus_read_lock(); 2735 ret = __netif_set_xps_queue(dev, cpumask_bits(mask), index, XPS_CPUS); 2736 cpus_read_unlock(); 2737 2738 return ret; 2739 } 2740 EXPORT_SYMBOL(netif_set_xps_queue); 2741 2742 #endif 2743 static void netdev_unbind_all_sb_channels(struct net_device *dev) 2744 { 2745 struct netdev_queue *txq = &dev->_tx[dev->num_tx_queues]; 2746 2747 /* Unbind any subordinate channels */ 2748 while (txq-- != &dev->_tx[0]) { 2749 if (txq->sb_dev) 2750 netdev_unbind_sb_channel(dev, txq->sb_dev); 2751 } 2752 } 2753 2754 void netdev_reset_tc(struct net_device *dev) 2755 { 2756 #ifdef CONFIG_XPS 2757 netif_reset_xps_queues_gt(dev, 0); 2758 #endif 2759 netdev_unbind_all_sb_channels(dev); 2760 2761 /* Reset TC configuration of device */ 2762 dev->num_tc = 0; 2763 memset(dev->tc_to_txq, 0, sizeof(dev->tc_to_txq)); 2764 memset(dev->prio_tc_map, 0, sizeof(dev->prio_tc_map)); 2765 } 2766 EXPORT_SYMBOL(netdev_reset_tc); 2767 2768 int netdev_set_tc_queue(struct net_device *dev, u8 tc, u16 count, u16 offset) 2769 { 2770 if (tc >= dev->num_tc) 2771 return -EINVAL; 2772 2773 #ifdef CONFIG_XPS 2774 netif_reset_xps_queues(dev, offset, count); 2775 #endif 2776 dev->tc_to_txq[tc].count = count; 2777 dev->tc_to_txq[tc].offset = offset; 2778 return 0; 2779 } 2780 EXPORT_SYMBOL(netdev_set_tc_queue); 2781 2782 int netdev_set_num_tc(struct net_device *dev, u8 num_tc) 2783 { 2784 if (num_tc > TC_MAX_QUEUE) 2785 return -EINVAL; 2786 2787 #ifdef CONFIG_XPS 2788 netif_reset_xps_queues_gt(dev, 0); 2789 #endif 2790 netdev_unbind_all_sb_channels(dev); 2791 2792 dev->num_tc = num_tc; 2793 return 0; 2794 } 2795 EXPORT_SYMBOL(netdev_set_num_tc); 2796 2797 void netdev_unbind_sb_channel(struct net_device *dev, 2798 struct net_device *sb_dev) 2799 { 2800 struct netdev_queue *txq = &dev->_tx[dev->num_tx_queues]; 2801 2802 #ifdef CONFIG_XPS 2803 netif_reset_xps_queues_gt(sb_dev, 0); 2804 #endif 2805 memset(sb_dev->tc_to_txq, 0, sizeof(sb_dev->tc_to_txq)); 2806 memset(sb_dev->prio_tc_map, 0, sizeof(sb_dev->prio_tc_map)); 2807 2808 while (txq-- != &dev->_tx[0]) { 2809 if (txq->sb_dev == sb_dev) 2810 txq->sb_dev = NULL; 2811 } 2812 } 2813 EXPORT_SYMBOL(netdev_unbind_sb_channel); 2814 2815 int netdev_bind_sb_channel_queue(struct net_device *dev, 2816 struct net_device *sb_dev, 2817 u8 tc, u16 count, u16 offset) 2818 { 2819 /* Make certain the sb_dev and dev are already configured */ 2820 if (sb_dev->num_tc >= 0 || tc >= dev->num_tc) 2821 return -EINVAL; 2822 2823 /* We cannot hand out queues we don't have */ 2824 if ((offset + count) > dev->real_num_tx_queues) 2825 return -EINVAL; 2826 2827 /* Record the mapping */ 2828 sb_dev->tc_to_txq[tc].count = count; 2829 sb_dev->tc_to_txq[tc].offset = offset; 2830 2831 /* Provide a way for Tx queue to find the tc_to_txq map or 2832 * XPS map for itself. 2833 */ 2834 while (count--) 2835 netdev_get_tx_queue(dev, count + offset)->sb_dev = sb_dev; 2836 2837 return 0; 2838 } 2839 EXPORT_SYMBOL(netdev_bind_sb_channel_queue); 2840 2841 int netdev_set_sb_channel(struct net_device *dev, u16 channel) 2842 { 2843 /* Do not use a multiqueue device to represent a subordinate channel */ 2844 if (netif_is_multiqueue(dev)) 2845 return -ENODEV; 2846 2847 /* We allow channels 1 - 32767 to be used for subordinate channels. 2848 * Channel 0 is meant to be "native" mode and used only to represent 2849 * the main root device. We allow writing 0 to reset the device back 2850 * to normal mode after being used as a subordinate channel. 2851 */ 2852 if (channel > S16_MAX) 2853 return -EINVAL; 2854 2855 dev->num_tc = -channel; 2856 2857 return 0; 2858 } 2859 EXPORT_SYMBOL(netdev_set_sb_channel); 2860 2861 /* 2862 * Routine to help set real_num_tx_queues. To avoid skbs mapped to queues 2863 * greater than real_num_tx_queues stale skbs on the qdisc must be flushed. 2864 */ 2865 int netif_set_real_num_tx_queues(struct net_device *dev, unsigned int txq) 2866 { 2867 bool disabling; 2868 int rc; 2869 2870 disabling = txq < dev->real_num_tx_queues; 2871 2872 if (txq < 1 || txq > dev->num_tx_queues) 2873 return -EINVAL; 2874 2875 if (dev->reg_state == NETREG_REGISTERED || 2876 dev->reg_state == NETREG_UNREGISTERING) { 2877 ASSERT_RTNL(); 2878 2879 rc = netdev_queue_update_kobjects(dev, dev->real_num_tx_queues, 2880 txq); 2881 if (rc) 2882 return rc; 2883 2884 if (dev->num_tc) 2885 netif_setup_tc(dev, txq); 2886 2887 dev_qdisc_change_real_num_tx(dev, txq); 2888 2889 dev->real_num_tx_queues = txq; 2890 2891 if (disabling) { 2892 synchronize_net(); 2893 qdisc_reset_all_tx_gt(dev, txq); 2894 #ifdef CONFIG_XPS 2895 netif_reset_xps_queues_gt(dev, txq); 2896 #endif 2897 } 2898 } else { 2899 dev->real_num_tx_queues = txq; 2900 } 2901 2902 return 0; 2903 } 2904 EXPORT_SYMBOL(netif_set_real_num_tx_queues); 2905 2906 #ifdef CONFIG_SYSFS 2907 /** 2908 * netif_set_real_num_rx_queues - set actual number of RX queues used 2909 * @dev: Network device 2910 * @rxq: Actual number of RX queues 2911 * 2912 * This must be called either with the rtnl_lock held or before 2913 * registration of the net device. Returns 0 on success, or a 2914 * negative error code. If called before registration, it always 2915 * succeeds. 2916 */ 2917 int netif_set_real_num_rx_queues(struct net_device *dev, unsigned int rxq) 2918 { 2919 int rc; 2920 2921 if (rxq < 1 || rxq > dev->num_rx_queues) 2922 return -EINVAL; 2923 2924 if (dev->reg_state == NETREG_REGISTERED) { 2925 ASSERT_RTNL(); 2926 2927 rc = net_rx_queue_update_kobjects(dev, dev->real_num_rx_queues, 2928 rxq); 2929 if (rc) 2930 return rc; 2931 } 2932 2933 dev->real_num_rx_queues = rxq; 2934 return 0; 2935 } 2936 EXPORT_SYMBOL(netif_set_real_num_rx_queues); 2937 #endif 2938 2939 /** 2940 * netif_set_real_num_queues - set actual number of RX and TX queues used 2941 * @dev: Network device 2942 * @txq: Actual number of TX queues 2943 * @rxq: Actual number of RX queues 2944 * 2945 * Set the real number of both TX and RX queues. 2946 * Does nothing if the number of queues is already correct. 2947 */ 2948 int netif_set_real_num_queues(struct net_device *dev, 2949 unsigned int txq, unsigned int rxq) 2950 { 2951 unsigned int old_rxq = dev->real_num_rx_queues; 2952 int err; 2953 2954 if (txq < 1 || txq > dev->num_tx_queues || 2955 rxq < 1 || rxq > dev->num_rx_queues) 2956 return -EINVAL; 2957 2958 /* Start from increases, so the error path only does decreases - 2959 * decreases can't fail. 2960 */ 2961 if (rxq > dev->real_num_rx_queues) { 2962 err = netif_set_real_num_rx_queues(dev, rxq); 2963 if (err) 2964 return err; 2965 } 2966 if (txq > dev->real_num_tx_queues) { 2967 err = netif_set_real_num_tx_queues(dev, txq); 2968 if (err) 2969 goto undo_rx; 2970 } 2971 if (rxq < dev->real_num_rx_queues) 2972 WARN_ON(netif_set_real_num_rx_queues(dev, rxq)); 2973 if (txq < dev->real_num_tx_queues) 2974 WARN_ON(netif_set_real_num_tx_queues(dev, txq)); 2975 2976 return 0; 2977 undo_rx: 2978 WARN_ON(netif_set_real_num_rx_queues(dev, old_rxq)); 2979 return err; 2980 } 2981 EXPORT_SYMBOL(netif_set_real_num_queues); 2982 2983 /** 2984 * netif_set_tso_max_size() - set the max size of TSO frames supported 2985 * @dev: netdev to update 2986 * @size: max skb->len of a TSO frame 2987 * 2988 * Set the limit on the size of TSO super-frames the device can handle. 2989 * Unless explicitly set the stack will assume the value of 2990 * %GSO_LEGACY_MAX_SIZE. 2991 */ 2992 void netif_set_tso_max_size(struct net_device *dev, unsigned int size) 2993 { 2994 dev->tso_max_size = min(GSO_MAX_SIZE, size); 2995 if (size < READ_ONCE(dev->gso_max_size)) 2996 netif_set_gso_max_size(dev, size); 2997 if (size < READ_ONCE(dev->gso_ipv4_max_size)) 2998 netif_set_gso_ipv4_max_size(dev, size); 2999 } 3000 EXPORT_SYMBOL(netif_set_tso_max_size); 3001 3002 /** 3003 * netif_set_tso_max_segs() - set the max number of segs supported for TSO 3004 * @dev: netdev to update 3005 * @segs: max number of TCP segments 3006 * 3007 * Set the limit on the number of TCP segments the device can generate from 3008 * a single TSO super-frame. 3009 * Unless explicitly set the stack will assume the value of %GSO_MAX_SEGS. 3010 */ 3011 void netif_set_tso_max_segs(struct net_device *dev, unsigned int segs) 3012 { 3013 dev->tso_max_segs = segs; 3014 if (segs < READ_ONCE(dev->gso_max_segs)) 3015 netif_set_gso_max_segs(dev, segs); 3016 } 3017 EXPORT_SYMBOL(netif_set_tso_max_segs); 3018 3019 /** 3020 * netif_inherit_tso_max() - copy all TSO limits from a lower device to an upper 3021 * @to: netdev to update 3022 * @from: netdev from which to copy the limits 3023 */ 3024 void netif_inherit_tso_max(struct net_device *to, const struct net_device *from) 3025 { 3026 netif_set_tso_max_size(to, from->tso_max_size); 3027 netif_set_tso_max_segs(to, from->tso_max_segs); 3028 } 3029 EXPORT_SYMBOL(netif_inherit_tso_max); 3030 3031 /** 3032 * netif_get_num_default_rss_queues - default number of RSS queues 3033 * 3034 * Default value is the number of physical cores if there are only 1 or 2, or 3035 * divided by 2 if there are more. 3036 */ 3037 int netif_get_num_default_rss_queues(void) 3038 { 3039 cpumask_var_t cpus; 3040 int cpu, count = 0; 3041 3042 if (unlikely(is_kdump_kernel() || !zalloc_cpumask_var(&cpus, GFP_KERNEL))) 3043 return 1; 3044 3045 cpumask_copy(cpus, cpu_online_mask); 3046 for_each_cpu(cpu, cpus) { 3047 ++count; 3048 cpumask_andnot(cpus, cpus, topology_sibling_cpumask(cpu)); 3049 } 3050 free_cpumask_var(cpus); 3051 3052 return count > 2 ? DIV_ROUND_UP(count, 2) : count; 3053 } 3054 EXPORT_SYMBOL(netif_get_num_default_rss_queues); 3055 3056 static void __netif_reschedule(struct Qdisc *q) 3057 { 3058 struct softnet_data *sd; 3059 unsigned long flags; 3060 3061 local_irq_save(flags); 3062 sd = this_cpu_ptr(&softnet_data); 3063 q->next_sched = NULL; 3064 *sd->output_queue_tailp = q; 3065 sd->output_queue_tailp = &q->next_sched; 3066 raise_softirq_irqoff(NET_TX_SOFTIRQ); 3067 local_irq_restore(flags); 3068 } 3069 3070 void __netif_schedule(struct Qdisc *q) 3071 { 3072 if (!test_and_set_bit(__QDISC_STATE_SCHED, &q->state)) 3073 __netif_reschedule(q); 3074 } 3075 EXPORT_SYMBOL(__netif_schedule); 3076 3077 struct dev_kfree_skb_cb { 3078 enum skb_drop_reason reason; 3079 }; 3080 3081 static struct dev_kfree_skb_cb *get_kfree_skb_cb(const struct sk_buff *skb) 3082 { 3083 return (struct dev_kfree_skb_cb *)skb->cb; 3084 } 3085 3086 void netif_schedule_queue(struct netdev_queue *txq) 3087 { 3088 rcu_read_lock(); 3089 if (!netif_xmit_stopped(txq)) { 3090 struct Qdisc *q = rcu_dereference(txq->qdisc); 3091 3092 __netif_schedule(q); 3093 } 3094 rcu_read_unlock(); 3095 } 3096 EXPORT_SYMBOL(netif_schedule_queue); 3097 3098 void netif_tx_wake_queue(struct netdev_queue *dev_queue) 3099 { 3100 if (test_and_clear_bit(__QUEUE_STATE_DRV_XOFF, &dev_queue->state)) { 3101 struct Qdisc *q; 3102 3103 rcu_read_lock(); 3104 q = rcu_dereference(dev_queue->qdisc); 3105 __netif_schedule(q); 3106 rcu_read_unlock(); 3107 } 3108 } 3109 EXPORT_SYMBOL(netif_tx_wake_queue); 3110 3111 void dev_kfree_skb_irq_reason(struct sk_buff *skb, enum skb_drop_reason reason) 3112 { 3113 unsigned long flags; 3114 3115 if (unlikely(!skb)) 3116 return; 3117 3118 if (likely(refcount_read(&skb->users) == 1)) { 3119 smp_rmb(); 3120 refcount_set(&skb->users, 0); 3121 } else if (likely(!refcount_dec_and_test(&skb->users))) { 3122 return; 3123 } 3124 get_kfree_skb_cb(skb)->reason = reason; 3125 local_irq_save(flags); 3126 skb->next = __this_cpu_read(softnet_data.completion_queue); 3127 __this_cpu_write(softnet_data.completion_queue, skb); 3128 raise_softirq_irqoff(NET_TX_SOFTIRQ); 3129 local_irq_restore(flags); 3130 } 3131 EXPORT_SYMBOL(dev_kfree_skb_irq_reason); 3132 3133 void dev_kfree_skb_any_reason(struct sk_buff *skb, enum skb_drop_reason reason) 3134 { 3135 if (in_hardirq() || irqs_disabled()) 3136 dev_kfree_skb_irq_reason(skb, reason); 3137 else 3138 kfree_skb_reason(skb, reason); 3139 } 3140 EXPORT_SYMBOL(dev_kfree_skb_any_reason); 3141 3142 3143 /** 3144 * netif_device_detach - mark device as removed 3145 * @dev: network device 3146 * 3147 * Mark device as removed from system and therefore no longer available. 3148 */ 3149 void netif_device_detach(struct net_device *dev) 3150 { 3151 if (test_and_clear_bit(__LINK_STATE_PRESENT, &dev->state) && 3152 netif_running(dev)) { 3153 netif_tx_stop_all_queues(dev); 3154 } 3155 } 3156 EXPORT_SYMBOL(netif_device_detach); 3157 3158 /** 3159 * netif_device_attach - mark device as attached 3160 * @dev: network device 3161 * 3162 * Mark device as attached from system and restart if needed. 3163 */ 3164 void netif_device_attach(struct net_device *dev) 3165 { 3166 if (!test_and_set_bit(__LINK_STATE_PRESENT, &dev->state) && 3167 netif_running(dev)) { 3168 netif_tx_wake_all_queues(dev); 3169 __netdev_watchdog_up(dev); 3170 } 3171 } 3172 EXPORT_SYMBOL(netif_device_attach); 3173 3174 /* 3175 * Returns a Tx hash based on the given packet descriptor a Tx queues' number 3176 * to be used as a distribution range. 3177 */ 3178 static u16 skb_tx_hash(const struct net_device *dev, 3179 const struct net_device *sb_dev, 3180 struct sk_buff *skb) 3181 { 3182 u32 hash; 3183 u16 qoffset = 0; 3184 u16 qcount = dev->real_num_tx_queues; 3185 3186 if (dev->num_tc) { 3187 u8 tc = netdev_get_prio_tc_map(dev, skb->priority); 3188 3189 qoffset = sb_dev->tc_to_txq[tc].offset; 3190 qcount = sb_dev->tc_to_txq[tc].count; 3191 if (unlikely(!qcount)) { 3192 net_warn_ratelimited("%s: invalid qcount, qoffset %u for tc %u\n", 3193 sb_dev->name, qoffset, tc); 3194 qoffset = 0; 3195 qcount = dev->real_num_tx_queues; 3196 } 3197 } 3198 3199 if (skb_rx_queue_recorded(skb)) { 3200 DEBUG_NET_WARN_ON_ONCE(qcount == 0); 3201 hash = skb_get_rx_queue(skb); 3202 if (hash >= qoffset) 3203 hash -= qoffset; 3204 while (unlikely(hash >= qcount)) 3205 hash -= qcount; 3206 return hash + qoffset; 3207 } 3208 3209 return (u16) reciprocal_scale(skb_get_hash(skb), qcount) + qoffset; 3210 } 3211 3212 void skb_warn_bad_offload(const struct sk_buff *skb) 3213 { 3214 static const netdev_features_t null_features; 3215 struct net_device *dev = skb->dev; 3216 const char *name = ""; 3217 3218 if (!net_ratelimit()) 3219 return; 3220 3221 if (dev) { 3222 if (dev->dev.parent) 3223 name = dev_driver_string(dev->dev.parent); 3224 else 3225 name = netdev_name(dev); 3226 } 3227 skb_dump(KERN_WARNING, skb, false); 3228 WARN(1, "%s: caps=(%pNF, %pNF)\n", 3229 name, dev ? &dev->features : &null_features, 3230 skb->sk ? &skb->sk->sk_route_caps : &null_features); 3231 } 3232 3233 /* 3234 * Invalidate hardware checksum when packet is to be mangled, and 3235 * complete checksum manually on outgoing path. 3236 */ 3237 int skb_checksum_help(struct sk_buff *skb) 3238 { 3239 __wsum csum; 3240 int ret = 0, offset; 3241 3242 if (skb->ip_summed == CHECKSUM_COMPLETE) 3243 goto out_set_summed; 3244 3245 if (unlikely(skb_is_gso(skb))) { 3246 skb_warn_bad_offload(skb); 3247 return -EINVAL; 3248 } 3249 3250 /* Before computing a checksum, we should make sure no frag could 3251 * be modified by an external entity : checksum could be wrong. 3252 */ 3253 if (skb_has_shared_frag(skb)) { 3254 ret = __skb_linearize(skb); 3255 if (ret) 3256 goto out; 3257 } 3258 3259 offset = skb_checksum_start_offset(skb); 3260 ret = -EINVAL; 3261 if (WARN_ON_ONCE(offset >= skb_headlen(skb))) { 3262 DO_ONCE_LITE(skb_dump, KERN_ERR, skb, false); 3263 goto out; 3264 } 3265 csum = skb_checksum(skb, offset, skb->len - offset, 0); 3266 3267 offset += skb->csum_offset; 3268 if (WARN_ON_ONCE(offset + sizeof(__sum16) > skb_headlen(skb))) { 3269 DO_ONCE_LITE(skb_dump, KERN_ERR, skb, false); 3270 goto out; 3271 } 3272 ret = skb_ensure_writable(skb, offset + sizeof(__sum16)); 3273 if (ret) 3274 goto out; 3275 3276 *(__sum16 *)(skb->data + offset) = csum_fold(csum) ?: CSUM_MANGLED_0; 3277 out_set_summed: 3278 skb->ip_summed = CHECKSUM_NONE; 3279 out: 3280 return ret; 3281 } 3282 EXPORT_SYMBOL(skb_checksum_help); 3283 3284 int skb_crc32c_csum_help(struct sk_buff *skb) 3285 { 3286 __le32 crc32c_csum; 3287 int ret = 0, offset, start; 3288 3289 if (skb->ip_summed != CHECKSUM_PARTIAL) 3290 goto out; 3291 3292 if (unlikely(skb_is_gso(skb))) 3293 goto out; 3294 3295 /* Before computing a checksum, we should make sure no frag could 3296 * be modified by an external entity : checksum could be wrong. 3297 */ 3298 if (unlikely(skb_has_shared_frag(skb))) { 3299 ret = __skb_linearize(skb); 3300 if (ret) 3301 goto out; 3302 } 3303 start = skb_checksum_start_offset(skb); 3304 offset = start + offsetof(struct sctphdr, checksum); 3305 if (WARN_ON_ONCE(offset >= skb_headlen(skb))) { 3306 ret = -EINVAL; 3307 goto out; 3308 } 3309 3310 ret = skb_ensure_writable(skb, offset + sizeof(__le32)); 3311 if (ret) 3312 goto out; 3313 3314 crc32c_csum = cpu_to_le32(~__skb_checksum(skb, start, 3315 skb->len - start, ~(__u32)0, 3316 crc32c_csum_stub)); 3317 *(__le32 *)(skb->data + offset) = crc32c_csum; 3318 skb_reset_csum_not_inet(skb); 3319 out: 3320 return ret; 3321 } 3322 3323 __be16 skb_network_protocol(struct sk_buff *skb, int *depth) 3324 { 3325 __be16 type = skb->protocol; 3326 3327 /* Tunnel gso handlers can set protocol to ethernet. */ 3328 if (type == htons(ETH_P_TEB)) { 3329 struct ethhdr *eth; 3330 3331 if (unlikely(!pskb_may_pull(skb, sizeof(struct ethhdr)))) 3332 return 0; 3333 3334 eth = (struct ethhdr *)skb->data; 3335 type = eth->h_proto; 3336 } 3337 3338 return vlan_get_protocol_and_depth(skb, type, depth); 3339 } 3340 3341 3342 /* Take action when hardware reception checksum errors are detected. */ 3343 #ifdef CONFIG_BUG 3344 static void do_netdev_rx_csum_fault(struct net_device *dev, struct sk_buff *skb) 3345 { 3346 netdev_err(dev, "hw csum failure\n"); 3347 skb_dump(KERN_ERR, skb, true); 3348 dump_stack(); 3349 } 3350 3351 void netdev_rx_csum_fault(struct net_device *dev, struct sk_buff *skb) 3352 { 3353 DO_ONCE_LITE(do_netdev_rx_csum_fault, dev, skb); 3354 } 3355 EXPORT_SYMBOL(netdev_rx_csum_fault); 3356 #endif 3357 3358 /* XXX: check that highmem exists at all on the given machine. */ 3359 static int illegal_highdma(struct net_device *dev, struct sk_buff *skb) 3360 { 3361 #ifdef CONFIG_HIGHMEM 3362 int i; 3363 3364 if (!(dev->features & NETIF_F_HIGHDMA)) { 3365 for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) { 3366 skb_frag_t *frag = &skb_shinfo(skb)->frags[i]; 3367 3368 if (PageHighMem(skb_frag_page(frag))) 3369 return 1; 3370 } 3371 } 3372 #endif 3373 return 0; 3374 } 3375 3376 /* If MPLS offload request, verify we are testing hardware MPLS features 3377 * instead of standard features for the netdev. 3378 */ 3379 #if IS_ENABLED(CONFIG_NET_MPLS_GSO) 3380 static netdev_features_t net_mpls_features(struct sk_buff *skb, 3381 netdev_features_t features, 3382 __be16 type) 3383 { 3384 if (eth_p_mpls(type)) 3385 features &= skb->dev->mpls_features; 3386 3387 return features; 3388 } 3389 #else 3390 static netdev_features_t net_mpls_features(struct sk_buff *skb, 3391 netdev_features_t features, 3392 __be16 type) 3393 { 3394 return features; 3395 } 3396 #endif 3397 3398 static netdev_features_t harmonize_features(struct sk_buff *skb, 3399 netdev_features_t features) 3400 { 3401 __be16 type; 3402 3403 type = skb_network_protocol(skb, NULL); 3404 features = net_mpls_features(skb, features, type); 3405 3406 if (skb->ip_summed != CHECKSUM_NONE && 3407 !can_checksum_protocol(features, type)) { 3408 features &= ~(NETIF_F_CSUM_MASK | NETIF_F_GSO_MASK); 3409 } 3410 if (illegal_highdma(skb->dev, skb)) 3411 features &= ~NETIF_F_SG; 3412 3413 return features; 3414 } 3415 3416 netdev_features_t passthru_features_check(struct sk_buff *skb, 3417 struct net_device *dev, 3418 netdev_features_t features) 3419 { 3420 return features; 3421 } 3422 EXPORT_SYMBOL(passthru_features_check); 3423 3424 static netdev_features_t dflt_features_check(struct sk_buff *skb, 3425 struct net_device *dev, 3426 netdev_features_t features) 3427 { 3428 return vlan_features_check(skb, features); 3429 } 3430 3431 static netdev_features_t gso_features_check(const struct sk_buff *skb, 3432 struct net_device *dev, 3433 netdev_features_t features) 3434 { 3435 u16 gso_segs = skb_shinfo(skb)->gso_segs; 3436 3437 if (gso_segs > READ_ONCE(dev->gso_max_segs)) 3438 return features & ~NETIF_F_GSO_MASK; 3439 3440 if (!skb_shinfo(skb)->gso_type) { 3441 skb_warn_bad_offload(skb); 3442 return features & ~NETIF_F_GSO_MASK; 3443 } 3444 3445 /* Support for GSO partial features requires software 3446 * intervention before we can actually process the packets 3447 * so we need to strip support for any partial features now 3448 * and we can pull them back in after we have partially 3449 * segmented the frame. 3450 */ 3451 if (!(skb_shinfo(skb)->gso_type & SKB_GSO_PARTIAL)) 3452 features &= ~dev->gso_partial_features; 3453 3454 /* Make sure to clear the IPv4 ID mangling feature if the 3455 * IPv4 header has the potential to be fragmented. 3456 */ 3457 if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV4) { 3458 struct iphdr *iph = skb->encapsulation ? 3459 inner_ip_hdr(skb) : ip_hdr(skb); 3460 3461 if (!(iph->frag_off & htons(IP_DF))) 3462 features &= ~NETIF_F_TSO_MANGLEID; 3463 } 3464 3465 return features; 3466 } 3467 3468 netdev_features_t netif_skb_features(struct sk_buff *skb) 3469 { 3470 struct net_device *dev = skb->dev; 3471 netdev_features_t features = dev->features; 3472 3473 if (skb_is_gso(skb)) 3474 features = gso_features_check(skb, dev, features); 3475 3476 /* If encapsulation offload request, verify we are testing 3477 * hardware encapsulation features instead of standard 3478 * features for the netdev 3479 */ 3480 if (skb->encapsulation) 3481 features &= dev->hw_enc_features; 3482 3483 if (skb_vlan_tagged(skb)) 3484 features = netdev_intersect_features(features, 3485 dev->vlan_features | 3486 NETIF_F_HW_VLAN_CTAG_TX | 3487 NETIF_F_HW_VLAN_STAG_TX); 3488 3489 if (dev->netdev_ops->ndo_features_check) 3490 features &= dev->netdev_ops->ndo_features_check(skb, dev, 3491 features); 3492 else 3493 features &= dflt_features_check(skb, dev, features); 3494 3495 return harmonize_features(skb, features); 3496 } 3497 EXPORT_SYMBOL(netif_skb_features); 3498 3499 static int xmit_one(struct sk_buff *skb, struct net_device *dev, 3500 struct netdev_queue *txq, bool more) 3501 { 3502 unsigned int len; 3503 int rc; 3504 3505 if (dev_nit_active(dev)) 3506 dev_queue_xmit_nit(skb, dev); 3507 3508 len = skb->len; 3509 trace_net_dev_start_xmit(skb, dev); 3510 rc = netdev_start_xmit(skb, dev, txq, more); 3511 trace_net_dev_xmit(skb, rc, dev, len); 3512 3513 return rc; 3514 } 3515 3516 struct sk_buff *dev_hard_start_xmit(struct sk_buff *first, struct net_device *dev, 3517 struct netdev_queue *txq, int *ret) 3518 { 3519 struct sk_buff *skb = first; 3520 int rc = NETDEV_TX_OK; 3521 3522 while (skb) { 3523 struct sk_buff *next = skb->next; 3524 3525 skb_mark_not_on_list(skb); 3526 rc = xmit_one(skb, dev, txq, next != NULL); 3527 if (unlikely(!dev_xmit_complete(rc))) { 3528 skb->next = next; 3529 goto out; 3530 } 3531 3532 skb = next; 3533 if (netif_tx_queue_stopped(txq) && skb) { 3534 rc = NETDEV_TX_BUSY; 3535 break; 3536 } 3537 } 3538 3539 out: 3540 *ret = rc; 3541 return skb; 3542 } 3543 3544 static struct sk_buff *validate_xmit_vlan(struct sk_buff *skb, 3545 netdev_features_t features) 3546 { 3547 if (skb_vlan_tag_present(skb) && 3548 !vlan_hw_offload_capable(features, skb->vlan_proto)) 3549 skb = __vlan_hwaccel_push_inside(skb); 3550 return skb; 3551 } 3552 3553 int skb_csum_hwoffload_help(struct sk_buff *skb, 3554 const netdev_features_t features) 3555 { 3556 if (unlikely(skb_csum_is_sctp(skb))) 3557 return !!(features & NETIF_F_SCTP_CRC) ? 0 : 3558 skb_crc32c_csum_help(skb); 3559 3560 if (features & NETIF_F_HW_CSUM) 3561 return 0; 3562 3563 if (features & (NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM)) { 3564 switch (skb->csum_offset) { 3565 case offsetof(struct tcphdr, check): 3566 case offsetof(struct udphdr, check): 3567 return 0; 3568 } 3569 } 3570 3571 return skb_checksum_help(skb); 3572 } 3573 EXPORT_SYMBOL(skb_csum_hwoffload_help); 3574 3575 static struct sk_buff *validate_xmit_skb(struct sk_buff *skb, struct net_device *dev, bool *again) 3576 { 3577 netdev_features_t features; 3578 3579 features = netif_skb_features(skb); 3580 skb = validate_xmit_vlan(skb, features); 3581 if (unlikely(!skb)) 3582 goto out_null; 3583 3584 skb = sk_validate_xmit_skb(skb, dev); 3585 if (unlikely(!skb)) 3586 goto out_null; 3587 3588 if (netif_needs_gso(skb, features)) { 3589 struct sk_buff *segs; 3590 3591 segs = skb_gso_segment(skb, features); 3592 if (IS_ERR(segs)) { 3593 goto out_kfree_skb; 3594 } else if (segs) { 3595 consume_skb(skb); 3596 skb = segs; 3597 } 3598 } else { 3599 if (skb_needs_linearize(skb, features) && 3600 __skb_linearize(skb)) 3601 goto out_kfree_skb; 3602 3603 /* If packet is not checksummed and device does not 3604 * support checksumming for this protocol, complete 3605 * checksumming here. 3606 */ 3607 if (skb->ip_summed == CHECKSUM_PARTIAL) { 3608 if (skb->encapsulation) 3609 skb_set_inner_transport_header(skb, 3610 skb_checksum_start_offset(skb)); 3611 else 3612 skb_set_transport_header(skb, 3613 skb_checksum_start_offset(skb)); 3614 if (skb_csum_hwoffload_help(skb, features)) 3615 goto out_kfree_skb; 3616 } 3617 } 3618 3619 skb = validate_xmit_xfrm(skb, features, again); 3620 3621 return skb; 3622 3623 out_kfree_skb: 3624 kfree_skb(skb); 3625 out_null: 3626 dev_core_stats_tx_dropped_inc(dev); 3627 return NULL; 3628 } 3629 3630 struct sk_buff *validate_xmit_skb_list(struct sk_buff *skb, struct net_device *dev, bool *again) 3631 { 3632 struct sk_buff *next, *head = NULL, *tail; 3633 3634 for (; skb != NULL; skb = next) { 3635 next = skb->next; 3636 skb_mark_not_on_list(skb); 3637 3638 /* in case skb wont be segmented, point to itself */ 3639 skb->prev = skb; 3640 3641 skb = validate_xmit_skb(skb, dev, again); 3642 if (!skb) 3643 continue; 3644 3645 if (!head) 3646 head = skb; 3647 else 3648 tail->next = skb; 3649 /* If skb was segmented, skb->prev points to 3650 * the last segment. If not, it still contains skb. 3651 */ 3652 tail = skb->prev; 3653 } 3654 return head; 3655 } 3656 EXPORT_SYMBOL_GPL(validate_xmit_skb_list); 3657 3658 static void qdisc_pkt_len_init(struct sk_buff *skb) 3659 { 3660 const struct skb_shared_info *shinfo = skb_shinfo(skb); 3661 3662 qdisc_skb_cb(skb)->pkt_len = skb->len; 3663 3664 /* To get more precise estimation of bytes sent on wire, 3665 * we add to pkt_len the headers size of all segments 3666 */ 3667 if (shinfo->gso_size && skb_transport_header_was_set(skb)) { 3668 u16 gso_segs = shinfo->gso_segs; 3669 unsigned int hdr_len; 3670 3671 /* mac layer + network layer */ 3672 hdr_len = skb_transport_offset(skb); 3673 3674 /* + transport layer */ 3675 if (likely(shinfo->gso_type & (SKB_GSO_TCPV4 | SKB_GSO_TCPV6))) { 3676 const struct tcphdr *th; 3677 struct tcphdr _tcphdr; 3678 3679 th = skb_header_pointer(skb, hdr_len, 3680 sizeof(_tcphdr), &_tcphdr); 3681 if (likely(th)) 3682 hdr_len += __tcp_hdrlen(th); 3683 } else { 3684 struct udphdr _udphdr; 3685 3686 if (skb_header_pointer(skb, hdr_len, 3687 sizeof(_udphdr), &_udphdr)) 3688 hdr_len += sizeof(struct udphdr); 3689 } 3690 3691 if (shinfo->gso_type & SKB_GSO_DODGY) 3692 gso_segs = DIV_ROUND_UP(skb->len - hdr_len, 3693 shinfo->gso_size); 3694 3695 qdisc_skb_cb(skb)->pkt_len += (gso_segs - 1) * hdr_len; 3696 } 3697 } 3698 3699 static int dev_qdisc_enqueue(struct sk_buff *skb, struct Qdisc *q, 3700 struct sk_buff **to_free, 3701 struct netdev_queue *txq) 3702 { 3703 int rc; 3704 3705 rc = q->enqueue(skb, q, to_free) & NET_XMIT_MASK; 3706 if (rc == NET_XMIT_SUCCESS) 3707 trace_qdisc_enqueue(q, txq, skb); 3708 return rc; 3709 } 3710 3711 static inline int __dev_xmit_skb(struct sk_buff *skb, struct Qdisc *q, 3712 struct net_device *dev, 3713 struct netdev_queue *txq) 3714 { 3715 spinlock_t *root_lock = qdisc_lock(q); 3716 struct sk_buff *to_free = NULL; 3717 bool contended; 3718 int rc; 3719 3720 qdisc_calculate_pkt_len(skb, q); 3721 3722 if (q->flags & TCQ_F_NOLOCK) { 3723 if (q->flags & TCQ_F_CAN_BYPASS && nolock_qdisc_is_empty(q) && 3724 qdisc_run_begin(q)) { 3725 /* Retest nolock_qdisc_is_empty() within the protection 3726 * of q->seqlock to protect from racing with requeuing. 3727 */ 3728 if (unlikely(!nolock_qdisc_is_empty(q))) { 3729 rc = dev_qdisc_enqueue(skb, q, &to_free, txq); 3730 __qdisc_run(q); 3731 qdisc_run_end(q); 3732 3733 goto no_lock_out; 3734 } 3735 3736 qdisc_bstats_cpu_update(q, skb); 3737 if (sch_direct_xmit(skb, q, dev, txq, NULL, true) && 3738 !nolock_qdisc_is_empty(q)) 3739 __qdisc_run(q); 3740 3741 qdisc_run_end(q); 3742 return NET_XMIT_SUCCESS; 3743 } 3744 3745 rc = dev_qdisc_enqueue(skb, q, &to_free, txq); 3746 qdisc_run(q); 3747 3748 no_lock_out: 3749 if (unlikely(to_free)) 3750 kfree_skb_list_reason(to_free, 3751 SKB_DROP_REASON_QDISC_DROP); 3752 return rc; 3753 } 3754 3755 /* 3756 * Heuristic to force contended enqueues to serialize on a 3757 * separate lock before trying to get qdisc main lock. 3758 * This permits qdisc->running owner to get the lock more 3759 * often and dequeue packets faster. 3760 * On PREEMPT_RT it is possible to preempt the qdisc owner during xmit 3761 * and then other tasks will only enqueue packets. The packets will be 3762 * sent after the qdisc owner is scheduled again. To prevent this 3763 * scenario the task always serialize on the lock. 3764 */ 3765 contended = qdisc_is_running(q) || IS_ENABLED(CONFIG_PREEMPT_RT); 3766 if (unlikely(contended)) 3767 spin_lock(&q->busylock); 3768 3769 spin_lock(root_lock); 3770 if (unlikely(test_bit(__QDISC_STATE_DEACTIVATED, &q->state))) { 3771 __qdisc_drop(skb, &to_free); 3772 rc = NET_XMIT_DROP; 3773 } else if ((q->flags & TCQ_F_CAN_BYPASS) && !qdisc_qlen(q) && 3774 qdisc_run_begin(q)) { 3775 /* 3776 * This is a work-conserving queue; there are no old skbs 3777 * waiting to be sent out; and the qdisc is not running - 3778 * xmit the skb directly. 3779 */ 3780 3781 qdisc_bstats_update(q, skb); 3782 3783 if (sch_direct_xmit(skb, q, dev, txq, root_lock, true)) { 3784 if (unlikely(contended)) { 3785 spin_unlock(&q->busylock); 3786 contended = false; 3787 } 3788 __qdisc_run(q); 3789 } 3790 3791 qdisc_run_end(q); 3792 rc = NET_XMIT_SUCCESS; 3793 } else { 3794 rc = dev_qdisc_enqueue(skb, q, &to_free, txq); 3795 if (qdisc_run_begin(q)) { 3796 if (unlikely(contended)) { 3797 spin_unlock(&q->busylock); 3798 contended = false; 3799 } 3800 __qdisc_run(q); 3801 qdisc_run_end(q); 3802 } 3803 } 3804 spin_unlock(root_lock); 3805 if (unlikely(to_free)) 3806 kfree_skb_list_reason(to_free, SKB_DROP_REASON_QDISC_DROP); 3807 if (unlikely(contended)) 3808 spin_unlock(&q->busylock); 3809 return rc; 3810 } 3811 3812 #if IS_ENABLED(CONFIG_CGROUP_NET_PRIO) 3813 static void skb_update_prio(struct sk_buff *skb) 3814 { 3815 const struct netprio_map *map; 3816 const struct sock *sk; 3817 unsigned int prioidx; 3818 3819 if (skb->priority) 3820 return; 3821 map = rcu_dereference_bh(skb->dev->priomap); 3822 if (!map) 3823 return; 3824 sk = skb_to_full_sk(skb); 3825 if (!sk) 3826 return; 3827 3828 prioidx = sock_cgroup_prioidx(&sk->sk_cgrp_data); 3829 3830 if (prioidx < map->priomap_len) 3831 skb->priority = map->priomap[prioidx]; 3832 } 3833 #else 3834 #define skb_update_prio(skb) 3835 #endif 3836 3837 /** 3838 * dev_loopback_xmit - loop back @skb 3839 * @net: network namespace this loopback is happening in 3840 * @sk: sk needed to be a netfilter okfn 3841 * @skb: buffer to transmit 3842 */ 3843 int dev_loopback_xmit(struct net *net, struct sock *sk, struct sk_buff *skb) 3844 { 3845 skb_reset_mac_header(skb); 3846 __skb_pull(skb, skb_network_offset(skb)); 3847 skb->pkt_type = PACKET_LOOPBACK; 3848 if (skb->ip_summed == CHECKSUM_NONE) 3849 skb->ip_summed = CHECKSUM_UNNECESSARY; 3850 DEBUG_NET_WARN_ON_ONCE(!skb_dst(skb)); 3851 skb_dst_force(skb); 3852 netif_rx(skb); 3853 return 0; 3854 } 3855 EXPORT_SYMBOL(dev_loopback_xmit); 3856 3857 #ifdef CONFIG_NET_EGRESS 3858 static struct sk_buff * 3859 sch_handle_egress(struct sk_buff *skb, int *ret, struct net_device *dev) 3860 { 3861 #ifdef CONFIG_NET_CLS_ACT 3862 struct mini_Qdisc *miniq = rcu_dereference_bh(dev->miniq_egress); 3863 struct tcf_result cl_res; 3864 3865 if (!miniq) 3866 return skb; 3867 3868 /* qdisc_skb_cb(skb)->pkt_len was already set by the caller. */ 3869 tc_skb_cb(skb)->mru = 0; 3870 tc_skb_cb(skb)->post_ct = false; 3871 mini_qdisc_bstats_cpu_update(miniq, skb); 3872 3873 switch (tcf_classify(skb, miniq->block, miniq->filter_list, &cl_res, false)) { 3874 case TC_ACT_OK: 3875 case TC_ACT_RECLASSIFY: 3876 skb->tc_index = TC_H_MIN(cl_res.classid); 3877 break; 3878 case TC_ACT_SHOT: 3879 mini_qdisc_qstats_cpu_drop(miniq); 3880 *ret = NET_XMIT_DROP; 3881 kfree_skb_reason(skb, SKB_DROP_REASON_TC_EGRESS); 3882 return NULL; 3883 case TC_ACT_STOLEN: 3884 case TC_ACT_QUEUED: 3885 case TC_ACT_TRAP: 3886 *ret = NET_XMIT_SUCCESS; 3887 consume_skb(skb); 3888 return NULL; 3889 case TC_ACT_REDIRECT: 3890 /* No need to push/pop skb's mac_header here on egress! */ 3891 skb_do_redirect(skb); 3892 *ret = NET_XMIT_SUCCESS; 3893 return NULL; 3894 default: 3895 break; 3896 } 3897 #endif /* CONFIG_NET_CLS_ACT */ 3898 3899 return skb; 3900 } 3901 3902 static struct netdev_queue * 3903 netdev_tx_queue_mapping(struct net_device *dev, struct sk_buff *skb) 3904 { 3905 int qm = skb_get_queue_mapping(skb); 3906 3907 return netdev_get_tx_queue(dev, netdev_cap_txqueue(dev, qm)); 3908 } 3909 3910 static bool netdev_xmit_txqueue_skipped(void) 3911 { 3912 return __this_cpu_read(softnet_data.xmit.skip_txqueue); 3913 } 3914 3915 void netdev_xmit_skip_txqueue(bool skip) 3916 { 3917 __this_cpu_write(softnet_data.xmit.skip_txqueue, skip); 3918 } 3919 EXPORT_SYMBOL_GPL(netdev_xmit_skip_txqueue); 3920 #endif /* CONFIG_NET_EGRESS */ 3921 3922 #ifdef CONFIG_XPS 3923 static int __get_xps_queue_idx(struct net_device *dev, struct sk_buff *skb, 3924 struct xps_dev_maps *dev_maps, unsigned int tci) 3925 { 3926 int tc = netdev_get_prio_tc_map(dev, skb->priority); 3927 struct xps_map *map; 3928 int queue_index = -1; 3929 3930 if (tc >= dev_maps->num_tc || tci >= dev_maps->nr_ids) 3931 return queue_index; 3932 3933 tci *= dev_maps->num_tc; 3934 tci += tc; 3935 3936 map = rcu_dereference(dev_maps->attr_map[tci]); 3937 if (map) { 3938 if (map->len == 1) 3939 queue_index = map->queues[0]; 3940 else 3941 queue_index = map->queues[reciprocal_scale( 3942 skb_get_hash(skb), map->len)]; 3943 if (unlikely(queue_index >= dev->real_num_tx_queues)) 3944 queue_index = -1; 3945 } 3946 return queue_index; 3947 } 3948 #endif 3949 3950 static int get_xps_queue(struct net_device *dev, struct net_device *sb_dev, 3951 struct sk_buff *skb) 3952 { 3953 #ifdef CONFIG_XPS 3954 struct xps_dev_maps *dev_maps; 3955 struct sock *sk = skb->sk; 3956 int queue_index = -1; 3957 3958 if (!static_key_false(&xps_needed)) 3959 return -1; 3960 3961 rcu_read_lock(); 3962 if (!static_key_false(&xps_rxqs_needed)) 3963 goto get_cpus_map; 3964 3965 dev_maps = rcu_dereference(sb_dev->xps_maps[XPS_RXQS]); 3966 if (dev_maps) { 3967 int tci = sk_rx_queue_get(sk); 3968 3969 if (tci >= 0) 3970 queue_index = __get_xps_queue_idx(dev, skb, dev_maps, 3971 tci); 3972 } 3973 3974 get_cpus_map: 3975 if (queue_index < 0) { 3976 dev_maps = rcu_dereference(sb_dev->xps_maps[XPS_CPUS]); 3977 if (dev_maps) { 3978 unsigned int tci = skb->sender_cpu - 1; 3979 3980 queue_index = __get_xps_queue_idx(dev, skb, dev_maps, 3981 tci); 3982 } 3983 } 3984 rcu_read_unlock(); 3985 3986 return queue_index; 3987 #else 3988 return -1; 3989 #endif 3990 } 3991 3992 u16 dev_pick_tx_zero(struct net_device *dev, struct sk_buff *skb, 3993 struct net_device *sb_dev) 3994 { 3995 return 0; 3996 } 3997 EXPORT_SYMBOL(dev_pick_tx_zero); 3998 3999 u16 dev_pick_tx_cpu_id(struct net_device *dev, struct sk_buff *skb, 4000 struct net_device *sb_dev) 4001 { 4002 return (u16)raw_smp_processor_id() % dev->real_num_tx_queues; 4003 } 4004 EXPORT_SYMBOL(dev_pick_tx_cpu_id); 4005 4006 u16 netdev_pick_tx(struct net_device *dev, struct sk_buff *skb, 4007 struct net_device *sb_dev) 4008 { 4009 struct sock *sk = skb->sk; 4010 int queue_index = sk_tx_queue_get(sk); 4011 4012 sb_dev = sb_dev ? : dev; 4013 4014 if (queue_index < 0 || skb->ooo_okay || 4015 queue_index >= dev->real_num_tx_queues) { 4016 int new_index = get_xps_queue(dev, sb_dev, skb); 4017 4018 if (new_index < 0) 4019 new_index = skb_tx_hash(dev, sb_dev, skb); 4020 4021 if (queue_index != new_index && sk && 4022 sk_fullsock(sk) && 4023 rcu_access_pointer(sk->sk_dst_cache)) 4024 sk_tx_queue_set(sk, new_index); 4025 4026 queue_index = new_index; 4027 } 4028 4029 return queue_index; 4030 } 4031 EXPORT_SYMBOL(netdev_pick_tx); 4032 4033 struct netdev_queue *netdev_core_pick_tx(struct net_device *dev, 4034 struct sk_buff *skb, 4035 struct net_device *sb_dev) 4036 { 4037 int queue_index = 0; 4038 4039 #ifdef CONFIG_XPS 4040 u32 sender_cpu = skb->sender_cpu - 1; 4041 4042 if (sender_cpu >= (u32)NR_CPUS) 4043 skb->sender_cpu = raw_smp_processor_id() + 1; 4044 #endif 4045 4046 if (dev->real_num_tx_queues != 1) { 4047 const struct net_device_ops *ops = dev->netdev_ops; 4048 4049 if (ops->ndo_select_queue) 4050 queue_index = ops->ndo_select_queue(dev, skb, sb_dev); 4051 else 4052 queue_index = netdev_pick_tx(dev, skb, sb_dev); 4053 4054 queue_index = netdev_cap_txqueue(dev, queue_index); 4055 } 4056 4057 skb_set_queue_mapping(skb, queue_index); 4058 return netdev_get_tx_queue(dev, queue_index); 4059 } 4060 4061 /** 4062 * __dev_queue_xmit() - transmit a buffer 4063 * @skb: buffer to transmit 4064 * @sb_dev: suboordinate device used for L2 forwarding offload 4065 * 4066 * Queue a buffer for transmission to a network device. The caller must 4067 * have set the device and priority and built the buffer before calling 4068 * this function. The function can be called from an interrupt. 4069 * 4070 * When calling this method, interrupts MUST be enabled. This is because 4071 * the BH enable code must have IRQs enabled so that it will not deadlock. 4072 * 4073 * Regardless of the return value, the skb is consumed, so it is currently 4074 * difficult to retry a send to this method. (You can bump the ref count 4075 * before sending to hold a reference for retry if you are careful.) 4076 * 4077 * Return: 4078 * * 0 - buffer successfully transmitted 4079 * * positive qdisc return code - NET_XMIT_DROP etc. 4080 * * negative errno - other errors 4081 */ 4082 int __dev_queue_xmit(struct sk_buff *skb, struct net_device *sb_dev) 4083 { 4084 struct net_device *dev = skb->dev; 4085 struct netdev_queue *txq = NULL; 4086 struct Qdisc *q; 4087 int rc = -ENOMEM; 4088 bool again = false; 4089 4090 skb_reset_mac_header(skb); 4091 skb_assert_len(skb); 4092 4093 if (unlikely(skb_shinfo(skb)->tx_flags & SKBTX_SCHED_TSTAMP)) 4094 __skb_tstamp_tx(skb, NULL, NULL, skb->sk, SCM_TSTAMP_SCHED); 4095 4096 /* Disable soft irqs for various locks below. Also 4097 * stops preemption for RCU. 4098 */ 4099 rcu_read_lock_bh(); 4100 4101 skb_update_prio(skb); 4102 4103 qdisc_pkt_len_init(skb); 4104 #ifdef CONFIG_NET_CLS_ACT 4105 skb->tc_at_ingress = 0; 4106 #endif 4107 #ifdef CONFIG_NET_EGRESS 4108 if (static_branch_unlikely(&egress_needed_key)) { 4109 if (nf_hook_egress_active()) { 4110 skb = nf_hook_egress(skb, &rc, dev); 4111 if (!skb) 4112 goto out; 4113 } 4114 4115 netdev_xmit_skip_txqueue(false); 4116 4117 nf_skip_egress(skb, true); 4118 skb = sch_handle_egress(skb, &rc, dev); 4119 if (!skb) 4120 goto out; 4121 nf_skip_egress(skb, false); 4122 4123 if (netdev_xmit_txqueue_skipped()) 4124 txq = netdev_tx_queue_mapping(dev, skb); 4125 } 4126 #endif 4127 /* If device/qdisc don't need skb->dst, release it right now while 4128 * its hot in this cpu cache. 4129 */ 4130 if (dev->priv_flags & IFF_XMIT_DST_RELEASE) 4131 skb_dst_drop(skb); 4132 else 4133 skb_dst_force(skb); 4134 4135 if (!txq) 4136 txq = netdev_core_pick_tx(dev, skb, sb_dev); 4137 4138 q = rcu_dereference_bh(txq->qdisc); 4139 4140 trace_net_dev_queue(skb); 4141 if (q->enqueue) { 4142 rc = __dev_xmit_skb(skb, q, dev, txq); 4143 goto out; 4144 } 4145 4146 /* The device has no queue. Common case for software devices: 4147 * loopback, all the sorts of tunnels... 4148 4149 * Really, it is unlikely that netif_tx_lock protection is necessary 4150 * here. (f.e. loopback and IP tunnels are clean ignoring statistics 4151 * counters.) 4152 * However, it is possible, that they rely on protection 4153 * made by us here. 4154 4155 * Check this and shot the lock. It is not prone from deadlocks. 4156 *Either shot noqueue qdisc, it is even simpler 8) 4157 */ 4158 if (dev->flags & IFF_UP) { 4159 int cpu = smp_processor_id(); /* ok because BHs are off */ 4160 4161 /* Other cpus might concurrently change txq->xmit_lock_owner 4162 * to -1 or to their cpu id, but not to our id. 4163 */ 4164 if (READ_ONCE(txq->xmit_lock_owner) != cpu) { 4165 if (dev_xmit_recursion()) 4166 goto recursion_alert; 4167 4168 skb = validate_xmit_skb(skb, dev, &again); 4169 if (!skb) 4170 goto out; 4171 4172 HARD_TX_LOCK(dev, txq, cpu); 4173 4174 if (!netif_xmit_stopped(txq)) { 4175 dev_xmit_recursion_inc(); 4176 skb = dev_hard_start_xmit(skb, dev, txq, &rc); 4177 dev_xmit_recursion_dec(); 4178 if (dev_xmit_complete(rc)) { 4179 HARD_TX_UNLOCK(dev, txq); 4180 goto out; 4181 } 4182 } 4183 HARD_TX_UNLOCK(dev, txq); 4184 net_crit_ratelimited("Virtual device %s asks to queue packet!\n", 4185 dev->name); 4186 } else { 4187 /* Recursion is detected! It is possible, 4188 * unfortunately 4189 */ 4190 recursion_alert: 4191 net_crit_ratelimited("Dead loop on virtual device %s, fix it urgently!\n", 4192 dev->name); 4193 } 4194 } 4195 4196 rc = -ENETDOWN; 4197 rcu_read_unlock_bh(); 4198 4199 dev_core_stats_tx_dropped_inc(dev); 4200 kfree_skb_list(skb); 4201 return rc; 4202 out: 4203 rcu_read_unlock_bh(); 4204 return rc; 4205 } 4206 EXPORT_SYMBOL(__dev_queue_xmit); 4207 4208 int __dev_direct_xmit(struct sk_buff *skb, u16 queue_id) 4209 { 4210 struct net_device *dev = skb->dev; 4211 struct sk_buff *orig_skb = skb; 4212 struct netdev_queue *txq; 4213 int ret = NETDEV_TX_BUSY; 4214 bool again = false; 4215 4216 if (unlikely(!netif_running(dev) || 4217 !netif_carrier_ok(dev))) 4218 goto drop; 4219 4220 skb = validate_xmit_skb_list(skb, dev, &again); 4221 if (skb != orig_skb) 4222 goto drop; 4223 4224 skb_set_queue_mapping(skb, queue_id); 4225 txq = skb_get_tx_queue(dev, skb); 4226 4227 local_bh_disable(); 4228 4229 dev_xmit_recursion_inc(); 4230 HARD_TX_LOCK(dev, txq, smp_processor_id()); 4231 if (!netif_xmit_frozen_or_drv_stopped(txq)) 4232 ret = netdev_start_xmit(skb, dev, txq, false); 4233 HARD_TX_UNLOCK(dev, txq); 4234 dev_xmit_recursion_dec(); 4235 4236 local_bh_enable(); 4237 return ret; 4238 drop: 4239 dev_core_stats_tx_dropped_inc(dev); 4240 kfree_skb_list(skb); 4241 return NET_XMIT_DROP; 4242 } 4243 EXPORT_SYMBOL(__dev_direct_xmit); 4244 4245 /************************************************************************* 4246 * Receiver routines 4247 *************************************************************************/ 4248 4249 int netdev_max_backlog __read_mostly = 1000; 4250 EXPORT_SYMBOL(netdev_max_backlog); 4251 4252 int netdev_tstamp_prequeue __read_mostly = 1; 4253 unsigned int sysctl_skb_defer_max __read_mostly = 64; 4254 int netdev_budget __read_mostly = 300; 4255 /* Must be at least 2 jiffes to guarantee 1 jiffy timeout */ 4256 unsigned int __read_mostly netdev_budget_usecs = 2 * USEC_PER_SEC / HZ; 4257 int weight_p __read_mostly = 64; /* old backlog weight */ 4258 int dev_weight_rx_bias __read_mostly = 1; /* bias for backlog weight */ 4259 int dev_weight_tx_bias __read_mostly = 1; /* bias for output_queue quota */ 4260 int dev_rx_weight __read_mostly = 64; 4261 int dev_tx_weight __read_mostly = 64; 4262 4263 /* Called with irq disabled */ 4264 static inline void ____napi_schedule(struct softnet_data *sd, 4265 struct napi_struct *napi) 4266 { 4267 struct task_struct *thread; 4268 4269 lockdep_assert_irqs_disabled(); 4270 4271 if (test_bit(NAPI_STATE_THREADED, &napi->state)) { 4272 /* Paired with smp_mb__before_atomic() in 4273 * napi_enable()/dev_set_threaded(). 4274 * Use READ_ONCE() to guarantee a complete 4275 * read on napi->thread. Only call 4276 * wake_up_process() when it's not NULL. 4277 */ 4278 thread = READ_ONCE(napi->thread); 4279 if (thread) { 4280 /* Avoid doing set_bit() if the thread is in 4281 * INTERRUPTIBLE state, cause napi_thread_wait() 4282 * makes sure to proceed with napi polling 4283 * if the thread is explicitly woken from here. 4284 */ 4285 if (READ_ONCE(thread->__state) != TASK_INTERRUPTIBLE) 4286 set_bit(NAPI_STATE_SCHED_THREADED, &napi->state); 4287 wake_up_process(thread); 4288 return; 4289 } 4290 } 4291 4292 list_add_tail(&napi->poll_list, &sd->poll_list); 4293 WRITE_ONCE(napi->list_owner, smp_processor_id()); 4294 /* If not called from net_rx_action() 4295 * we have to raise NET_RX_SOFTIRQ. 4296 */ 4297 if (!sd->in_net_rx_action) 4298 __raise_softirq_irqoff(NET_RX_SOFTIRQ); 4299 } 4300 4301 #ifdef CONFIG_RPS 4302 4303 /* One global table that all flow-based protocols share. */ 4304 struct rps_sock_flow_table __rcu *rps_sock_flow_table __read_mostly; 4305 EXPORT_SYMBOL(rps_sock_flow_table); 4306 u32 rps_cpu_mask __read_mostly; 4307 EXPORT_SYMBOL(rps_cpu_mask); 4308 4309 struct static_key_false rps_needed __read_mostly; 4310 EXPORT_SYMBOL(rps_needed); 4311 struct static_key_false rfs_needed __read_mostly; 4312 EXPORT_SYMBOL(rfs_needed); 4313 4314 static struct rps_dev_flow * 4315 set_rps_cpu(struct net_device *dev, struct sk_buff *skb, 4316 struct rps_dev_flow *rflow, u16 next_cpu) 4317 { 4318 if (next_cpu < nr_cpu_ids) { 4319 #ifdef CONFIG_RFS_ACCEL 4320 struct netdev_rx_queue *rxqueue; 4321 struct rps_dev_flow_table *flow_table; 4322 struct rps_dev_flow *old_rflow; 4323 u32 flow_id; 4324 u16 rxq_index; 4325 int rc; 4326 4327 /* Should we steer this flow to a different hardware queue? */ 4328 if (!skb_rx_queue_recorded(skb) || !dev->rx_cpu_rmap || 4329 !(dev->features & NETIF_F_NTUPLE)) 4330 goto out; 4331 rxq_index = cpu_rmap_lookup_index(dev->rx_cpu_rmap, next_cpu); 4332 if (rxq_index == skb_get_rx_queue(skb)) 4333 goto out; 4334 4335 rxqueue = dev->_rx + rxq_index; 4336 flow_table = rcu_dereference(rxqueue->rps_flow_table); 4337 if (!flow_table) 4338 goto out; 4339 flow_id = skb_get_hash(skb) & flow_table->mask; 4340 rc = dev->netdev_ops->ndo_rx_flow_steer(dev, skb, 4341 rxq_index, flow_id); 4342 if (rc < 0) 4343 goto out; 4344 old_rflow = rflow; 4345 rflow = &flow_table->flows[flow_id]; 4346 rflow->filter = rc; 4347 if (old_rflow->filter == rflow->filter) 4348 old_rflow->filter = RPS_NO_FILTER; 4349 out: 4350 #endif 4351 rflow->last_qtail = 4352 per_cpu(softnet_data, next_cpu).input_queue_head; 4353 } 4354 4355 rflow->cpu = next_cpu; 4356 return rflow; 4357 } 4358 4359 /* 4360 * get_rps_cpu is called from netif_receive_skb and returns the target 4361 * CPU from the RPS map of the receiving queue for a given skb. 4362 * rcu_read_lock must be held on entry. 4363 */ 4364 static int get_rps_cpu(struct net_device *dev, struct sk_buff *skb, 4365 struct rps_dev_flow **rflowp) 4366 { 4367 const struct rps_sock_flow_table *sock_flow_table; 4368 struct netdev_rx_queue *rxqueue = dev->_rx; 4369 struct rps_dev_flow_table *flow_table; 4370 struct rps_map *map; 4371 int cpu = -1; 4372 u32 tcpu; 4373 u32 hash; 4374 4375 if (skb_rx_queue_recorded(skb)) { 4376 u16 index = skb_get_rx_queue(skb); 4377 4378 if (unlikely(index >= dev->real_num_rx_queues)) { 4379 WARN_ONCE(dev->real_num_rx_queues > 1, 4380 "%s received packet on queue %u, but number " 4381 "of RX queues is %u\n", 4382 dev->name, index, dev->real_num_rx_queues); 4383 goto done; 4384 } 4385 rxqueue += index; 4386 } 4387 4388 /* Avoid computing hash if RFS/RPS is not active for this rxqueue */ 4389 4390 flow_table = rcu_dereference(rxqueue->rps_flow_table); 4391 map = rcu_dereference(rxqueue->rps_map); 4392 if (!flow_table && !map) 4393 goto done; 4394 4395 skb_reset_network_header(skb); 4396 hash = skb_get_hash(skb); 4397 if (!hash) 4398 goto done; 4399 4400 sock_flow_table = rcu_dereference(rps_sock_flow_table); 4401 if (flow_table && sock_flow_table) { 4402 struct rps_dev_flow *rflow; 4403 u32 next_cpu; 4404 u32 ident; 4405 4406 /* First check into global flow table if there is a match. 4407 * This READ_ONCE() pairs with WRITE_ONCE() from rps_record_sock_flow(). 4408 */ 4409 ident = READ_ONCE(sock_flow_table->ents[hash & sock_flow_table->mask]); 4410 if ((ident ^ hash) & ~rps_cpu_mask) 4411 goto try_rps; 4412 4413 next_cpu = ident & rps_cpu_mask; 4414 4415 /* OK, now we know there is a match, 4416 * we can look at the local (per receive queue) flow table 4417 */ 4418 rflow = &flow_table->flows[hash & flow_table->mask]; 4419 tcpu = rflow->cpu; 4420 4421 /* 4422 * If the desired CPU (where last recvmsg was done) is 4423 * different from current CPU (one in the rx-queue flow 4424 * table entry), switch if one of the following holds: 4425 * - Current CPU is unset (>= nr_cpu_ids). 4426 * - Current CPU is offline. 4427 * - The current CPU's queue tail has advanced beyond the 4428 * last packet that was enqueued using this table entry. 4429 * This guarantees that all previous packets for the flow 4430 * have been dequeued, thus preserving in order delivery. 4431 */ 4432 if (unlikely(tcpu != next_cpu) && 4433 (tcpu >= nr_cpu_ids || !cpu_online(tcpu) || 4434 ((int)(per_cpu(softnet_data, tcpu).input_queue_head - 4435 rflow->last_qtail)) >= 0)) { 4436 tcpu = next_cpu; 4437 rflow = set_rps_cpu(dev, skb, rflow, next_cpu); 4438 } 4439 4440 if (tcpu < nr_cpu_ids && cpu_online(tcpu)) { 4441 *rflowp = rflow; 4442 cpu = tcpu; 4443 goto done; 4444 } 4445 } 4446 4447 try_rps: 4448 4449 if (map) { 4450 tcpu = map->cpus[reciprocal_scale(hash, map->len)]; 4451 if (cpu_online(tcpu)) { 4452 cpu = tcpu; 4453 goto done; 4454 } 4455 } 4456 4457 done: 4458 return cpu; 4459 } 4460 4461 #ifdef CONFIG_RFS_ACCEL 4462 4463 /** 4464 * rps_may_expire_flow - check whether an RFS hardware filter may be removed 4465 * @dev: Device on which the filter was set 4466 * @rxq_index: RX queue index 4467 * @flow_id: Flow ID passed to ndo_rx_flow_steer() 4468 * @filter_id: Filter ID returned by ndo_rx_flow_steer() 4469 * 4470 * Drivers that implement ndo_rx_flow_steer() should periodically call 4471 * this function for each installed filter and remove the filters for 4472 * which it returns %true. 4473 */ 4474 bool rps_may_expire_flow(struct net_device *dev, u16 rxq_index, 4475 u32 flow_id, u16 filter_id) 4476 { 4477 struct netdev_rx_queue *rxqueue = dev->_rx + rxq_index; 4478 struct rps_dev_flow_table *flow_table; 4479 struct rps_dev_flow *rflow; 4480 bool expire = true; 4481 unsigned int cpu; 4482 4483 rcu_read_lock(); 4484 flow_table = rcu_dereference(rxqueue->rps_flow_table); 4485 if (flow_table && flow_id <= flow_table->mask) { 4486 rflow = &flow_table->flows[flow_id]; 4487 cpu = READ_ONCE(rflow->cpu); 4488 if (rflow->filter == filter_id && cpu < nr_cpu_ids && 4489 ((int)(per_cpu(softnet_data, cpu).input_queue_head - 4490 rflow->last_qtail) < 4491 (int)(10 * flow_table->mask))) 4492 expire = false; 4493 } 4494 rcu_read_unlock(); 4495 return expire; 4496 } 4497 EXPORT_SYMBOL(rps_may_expire_flow); 4498 4499 #endif /* CONFIG_RFS_ACCEL */ 4500 4501 /* Called from hardirq (IPI) context */ 4502 static void rps_trigger_softirq(void *data) 4503 { 4504 struct softnet_data *sd = data; 4505 4506 ____napi_schedule(sd, &sd->backlog); 4507 sd->received_rps++; 4508 } 4509 4510 #endif /* CONFIG_RPS */ 4511 4512 /* Called from hardirq (IPI) context */ 4513 static void trigger_rx_softirq(void *data) 4514 { 4515 struct softnet_data *sd = data; 4516 4517 __raise_softirq_irqoff(NET_RX_SOFTIRQ); 4518 smp_store_release(&sd->defer_ipi_scheduled, 0); 4519 } 4520 4521 /* 4522 * After we queued a packet into sd->input_pkt_queue, 4523 * we need to make sure this queue is serviced soon. 4524 * 4525 * - If this is another cpu queue, link it to our rps_ipi_list, 4526 * and make sure we will process rps_ipi_list from net_rx_action(). 4527 * 4528 * - If this is our own queue, NAPI schedule our backlog. 4529 * Note that this also raises NET_RX_SOFTIRQ. 4530 */ 4531 static void napi_schedule_rps(struct softnet_data *sd) 4532 { 4533 struct softnet_data *mysd = this_cpu_ptr(&softnet_data); 4534 4535 #ifdef CONFIG_RPS 4536 if (sd != mysd) { 4537 sd->rps_ipi_next = mysd->rps_ipi_list; 4538 mysd->rps_ipi_list = sd; 4539 4540 /* If not called from net_rx_action() or napi_threaded_poll() 4541 * we have to raise NET_RX_SOFTIRQ. 4542 */ 4543 if (!mysd->in_net_rx_action && !mysd->in_napi_threaded_poll) 4544 __raise_softirq_irqoff(NET_RX_SOFTIRQ); 4545 return; 4546 } 4547 #endif /* CONFIG_RPS */ 4548 __napi_schedule_irqoff(&mysd->backlog); 4549 } 4550 4551 #ifdef CONFIG_NET_FLOW_LIMIT 4552 int netdev_flow_limit_table_len __read_mostly = (1 << 12); 4553 #endif 4554 4555 static bool skb_flow_limit(struct sk_buff *skb, unsigned int qlen) 4556 { 4557 #ifdef CONFIG_NET_FLOW_LIMIT 4558 struct sd_flow_limit *fl; 4559 struct softnet_data *sd; 4560 unsigned int old_flow, new_flow; 4561 4562 if (qlen < (READ_ONCE(netdev_max_backlog) >> 1)) 4563 return false; 4564 4565 sd = this_cpu_ptr(&softnet_data); 4566 4567 rcu_read_lock(); 4568 fl = rcu_dereference(sd->flow_limit); 4569 if (fl) { 4570 new_flow = skb_get_hash(skb) & (fl->num_buckets - 1); 4571 old_flow = fl->history[fl->history_head]; 4572 fl->history[fl->history_head] = new_flow; 4573 4574 fl->history_head++; 4575 fl->history_head &= FLOW_LIMIT_HISTORY - 1; 4576 4577 if (likely(fl->buckets[old_flow])) 4578 fl->buckets[old_flow]--; 4579 4580 if (++fl->buckets[new_flow] > (FLOW_LIMIT_HISTORY >> 1)) { 4581 fl->count++; 4582 rcu_read_unlock(); 4583 return true; 4584 } 4585 } 4586 rcu_read_unlock(); 4587 #endif 4588 return false; 4589 } 4590 4591 /* 4592 * enqueue_to_backlog is called to queue an skb to a per CPU backlog 4593 * queue (may be a remote CPU queue). 4594 */ 4595 static int enqueue_to_backlog(struct sk_buff *skb, int cpu, 4596 unsigned int *qtail) 4597 { 4598 enum skb_drop_reason reason; 4599 struct softnet_data *sd; 4600 unsigned long flags; 4601 unsigned int qlen; 4602 4603 reason = SKB_DROP_REASON_NOT_SPECIFIED; 4604 sd = &per_cpu(softnet_data, cpu); 4605 4606 rps_lock_irqsave(sd, &flags); 4607 if (!netif_running(skb->dev)) 4608 goto drop; 4609 qlen = skb_queue_len(&sd->input_pkt_queue); 4610 if (qlen <= READ_ONCE(netdev_max_backlog) && !skb_flow_limit(skb, qlen)) { 4611 if (qlen) { 4612 enqueue: 4613 __skb_queue_tail(&sd->input_pkt_queue, skb); 4614 input_queue_tail_incr_save(sd, qtail); 4615 rps_unlock_irq_restore(sd, &flags); 4616 return NET_RX_SUCCESS; 4617 } 4618 4619 /* Schedule NAPI for backlog device 4620 * We can use non atomic operation since we own the queue lock 4621 */ 4622 if (!__test_and_set_bit(NAPI_STATE_SCHED, &sd->backlog.state)) 4623 napi_schedule_rps(sd); 4624 goto enqueue; 4625 } 4626 reason = SKB_DROP_REASON_CPU_BACKLOG; 4627 4628 drop: 4629 sd->dropped++; 4630 rps_unlock_irq_restore(sd, &flags); 4631 4632 dev_core_stats_rx_dropped_inc(skb->dev); 4633 kfree_skb_reason(skb, reason); 4634 return NET_RX_DROP; 4635 } 4636 4637 static struct netdev_rx_queue *netif_get_rxqueue(struct sk_buff *skb) 4638 { 4639 struct net_device *dev = skb->dev; 4640 struct netdev_rx_queue *rxqueue; 4641 4642 rxqueue = dev->_rx; 4643 4644 if (skb_rx_queue_recorded(skb)) { 4645 u16 index = skb_get_rx_queue(skb); 4646 4647 if (unlikely(index >= dev->real_num_rx_queues)) { 4648 WARN_ONCE(dev->real_num_rx_queues > 1, 4649 "%s received packet on queue %u, but number " 4650 "of RX queues is %u\n", 4651 dev->name, index, dev->real_num_rx_queues); 4652 4653 return rxqueue; /* Return first rxqueue */ 4654 } 4655 rxqueue += index; 4656 } 4657 return rxqueue; 4658 } 4659 4660 u32 bpf_prog_run_generic_xdp(struct sk_buff *skb, struct xdp_buff *xdp, 4661 struct bpf_prog *xdp_prog) 4662 { 4663 void *orig_data, *orig_data_end, *hard_start; 4664 struct netdev_rx_queue *rxqueue; 4665 bool orig_bcast, orig_host; 4666 u32 mac_len, frame_sz; 4667 __be16 orig_eth_type; 4668 struct ethhdr *eth; 4669 u32 metalen, act; 4670 int off; 4671 4672 /* The XDP program wants to see the packet starting at the MAC 4673 * header. 4674 */ 4675 mac_len = skb->data - skb_mac_header(skb); 4676 hard_start = skb->data - skb_headroom(skb); 4677 4678 /* SKB "head" area always have tailroom for skb_shared_info */ 4679 frame_sz = (void *)skb_end_pointer(skb) - hard_start; 4680 frame_sz += SKB_DATA_ALIGN(sizeof(struct skb_shared_info)); 4681 4682 rxqueue = netif_get_rxqueue(skb); 4683 xdp_init_buff(xdp, frame_sz, &rxqueue->xdp_rxq); 4684 xdp_prepare_buff(xdp, hard_start, skb_headroom(skb) - mac_len, 4685 skb_headlen(skb) + mac_len, true); 4686 4687 orig_data_end = xdp->data_end; 4688 orig_data = xdp->data; 4689 eth = (struct ethhdr *)xdp->data; 4690 orig_host = ether_addr_equal_64bits(eth->h_dest, skb->dev->dev_addr); 4691 orig_bcast = is_multicast_ether_addr_64bits(eth->h_dest); 4692 orig_eth_type = eth->h_proto; 4693 4694 act = bpf_prog_run_xdp(xdp_prog, xdp); 4695 4696 /* check if bpf_xdp_adjust_head was used */ 4697 off = xdp->data - orig_data; 4698 if (off) { 4699 if (off > 0) 4700 __skb_pull(skb, off); 4701 else if (off < 0) 4702 __skb_push(skb, -off); 4703 4704 skb->mac_header += off; 4705 skb_reset_network_header(skb); 4706 } 4707 4708 /* check if bpf_xdp_adjust_tail was used */ 4709 off = xdp->data_end - orig_data_end; 4710 if (off != 0) { 4711 skb_set_tail_pointer(skb, xdp->data_end - xdp->data); 4712 skb->len += off; /* positive on grow, negative on shrink */ 4713 } 4714 4715 /* check if XDP changed eth hdr such SKB needs update */ 4716 eth = (struct ethhdr *)xdp->data; 4717 if ((orig_eth_type != eth->h_proto) || 4718 (orig_host != ether_addr_equal_64bits(eth->h_dest, 4719 skb->dev->dev_addr)) || 4720 (orig_bcast != is_multicast_ether_addr_64bits(eth->h_dest))) { 4721 __skb_push(skb, ETH_HLEN); 4722 skb->pkt_type = PACKET_HOST; 4723 skb->protocol = eth_type_trans(skb, skb->dev); 4724 } 4725 4726 /* Redirect/Tx gives L2 packet, code that will reuse skb must __skb_pull 4727 * before calling us again on redirect path. We do not call do_redirect 4728 * as we leave that up to the caller. 4729 * 4730 * Caller is responsible for managing lifetime of skb (i.e. calling 4731 * kfree_skb in response to actions it cannot handle/XDP_DROP). 4732 */ 4733 switch (act) { 4734 case XDP_REDIRECT: 4735 case XDP_TX: 4736 __skb_push(skb, mac_len); 4737 break; 4738 case XDP_PASS: 4739 metalen = xdp->data - xdp->data_meta; 4740 if (metalen) 4741 skb_metadata_set(skb, metalen); 4742 break; 4743 } 4744 4745 return act; 4746 } 4747 4748 static u32 netif_receive_generic_xdp(struct sk_buff *skb, 4749 struct xdp_buff *xdp, 4750 struct bpf_prog *xdp_prog) 4751 { 4752 u32 act = XDP_DROP; 4753 4754 /* Reinjected packets coming from act_mirred or similar should 4755 * not get XDP generic processing. 4756 */ 4757 if (skb_is_redirected(skb)) 4758 return XDP_PASS; 4759 4760 /* XDP packets must be linear and must have sufficient headroom 4761 * of XDP_PACKET_HEADROOM bytes. This is the guarantee that also 4762 * native XDP provides, thus we need to do it here as well. 4763 */ 4764 if (skb_cloned(skb) || skb_is_nonlinear(skb) || 4765 skb_headroom(skb) < XDP_PACKET_HEADROOM) { 4766 int hroom = XDP_PACKET_HEADROOM - skb_headroom(skb); 4767 int troom = skb->tail + skb->data_len - skb->end; 4768 4769 /* In case we have to go down the path and also linearize, 4770 * then lets do the pskb_expand_head() work just once here. 4771 */ 4772 if (pskb_expand_head(skb, 4773 hroom > 0 ? ALIGN(hroom, NET_SKB_PAD) : 0, 4774 troom > 0 ? troom + 128 : 0, GFP_ATOMIC)) 4775 goto do_drop; 4776 if (skb_linearize(skb)) 4777 goto do_drop; 4778 } 4779 4780 act = bpf_prog_run_generic_xdp(skb, xdp, xdp_prog); 4781 switch (act) { 4782 case XDP_REDIRECT: 4783 case XDP_TX: 4784 case XDP_PASS: 4785 break; 4786 default: 4787 bpf_warn_invalid_xdp_action(skb->dev, xdp_prog, act); 4788 fallthrough; 4789 case XDP_ABORTED: 4790 trace_xdp_exception(skb->dev, xdp_prog, act); 4791 fallthrough; 4792 case XDP_DROP: 4793 do_drop: 4794 kfree_skb(skb); 4795 break; 4796 } 4797 4798 return act; 4799 } 4800 4801 /* When doing generic XDP we have to bypass the qdisc layer and the 4802 * network taps in order to match in-driver-XDP behavior. This also means 4803 * that XDP packets are able to starve other packets going through a qdisc, 4804 * and DDOS attacks will be more effective. In-driver-XDP use dedicated TX 4805 * queues, so they do not have this starvation issue. 4806 */ 4807 void generic_xdp_tx(struct sk_buff *skb, struct bpf_prog *xdp_prog) 4808 { 4809 struct net_device *dev = skb->dev; 4810 struct netdev_queue *txq; 4811 bool free_skb = true; 4812 int cpu, rc; 4813 4814 txq = netdev_core_pick_tx(dev, skb, NULL); 4815 cpu = smp_processor_id(); 4816 HARD_TX_LOCK(dev, txq, cpu); 4817 if (!netif_xmit_frozen_or_drv_stopped(txq)) { 4818 rc = netdev_start_xmit(skb, dev, txq, 0); 4819 if (dev_xmit_complete(rc)) 4820 free_skb = false; 4821 } 4822 HARD_TX_UNLOCK(dev, txq); 4823 if (free_skb) { 4824 trace_xdp_exception(dev, xdp_prog, XDP_TX); 4825 dev_core_stats_tx_dropped_inc(dev); 4826 kfree_skb(skb); 4827 } 4828 } 4829 4830 static DEFINE_STATIC_KEY_FALSE(generic_xdp_needed_key); 4831 4832 int do_xdp_generic(struct bpf_prog *xdp_prog, struct sk_buff *skb) 4833 { 4834 if (xdp_prog) { 4835 struct xdp_buff xdp; 4836 u32 act; 4837 int err; 4838 4839 act = netif_receive_generic_xdp(skb, &xdp, xdp_prog); 4840 if (act != XDP_PASS) { 4841 switch (act) { 4842 case XDP_REDIRECT: 4843 err = xdp_do_generic_redirect(skb->dev, skb, 4844 &xdp, xdp_prog); 4845 if (err) 4846 goto out_redir; 4847 break; 4848 case XDP_TX: 4849 generic_xdp_tx(skb, xdp_prog); 4850 break; 4851 } 4852 return XDP_DROP; 4853 } 4854 } 4855 return XDP_PASS; 4856 out_redir: 4857 kfree_skb_reason(skb, SKB_DROP_REASON_XDP); 4858 return XDP_DROP; 4859 } 4860 EXPORT_SYMBOL_GPL(do_xdp_generic); 4861 4862 static int netif_rx_internal(struct sk_buff *skb) 4863 { 4864 int ret; 4865 4866 net_timestamp_check(READ_ONCE(netdev_tstamp_prequeue), skb); 4867 4868 trace_netif_rx(skb); 4869 4870 #ifdef CONFIG_RPS 4871 if (static_branch_unlikely(&rps_needed)) { 4872 struct rps_dev_flow voidflow, *rflow = &voidflow; 4873 int cpu; 4874 4875 rcu_read_lock(); 4876 4877 cpu = get_rps_cpu(skb->dev, skb, &rflow); 4878 if (cpu < 0) 4879 cpu = smp_processor_id(); 4880 4881 ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail); 4882 4883 rcu_read_unlock(); 4884 } else 4885 #endif 4886 { 4887 unsigned int qtail; 4888 4889 ret = enqueue_to_backlog(skb, smp_processor_id(), &qtail); 4890 } 4891 return ret; 4892 } 4893 4894 /** 4895 * __netif_rx - Slightly optimized version of netif_rx 4896 * @skb: buffer to post 4897 * 4898 * This behaves as netif_rx except that it does not disable bottom halves. 4899 * As a result this function may only be invoked from the interrupt context 4900 * (either hard or soft interrupt). 4901 */ 4902 int __netif_rx(struct sk_buff *skb) 4903 { 4904 int ret; 4905 4906 lockdep_assert_once(hardirq_count() | softirq_count()); 4907 4908 trace_netif_rx_entry(skb); 4909 ret = netif_rx_internal(skb); 4910 trace_netif_rx_exit(ret); 4911 return ret; 4912 } 4913 EXPORT_SYMBOL(__netif_rx); 4914 4915 /** 4916 * netif_rx - post buffer to the network code 4917 * @skb: buffer to post 4918 * 4919 * This function receives a packet from a device driver and queues it for 4920 * the upper (protocol) levels to process via the backlog NAPI device. It 4921 * always succeeds. The buffer may be dropped during processing for 4922 * congestion control or by the protocol layers. 4923 * The network buffer is passed via the backlog NAPI device. Modern NIC 4924 * driver should use NAPI and GRO. 4925 * This function can used from interrupt and from process context. The 4926 * caller from process context must not disable interrupts before invoking 4927 * this function. 4928 * 4929 * return values: 4930 * NET_RX_SUCCESS (no congestion) 4931 * NET_RX_DROP (packet was dropped) 4932 * 4933 */ 4934 int netif_rx(struct sk_buff *skb) 4935 { 4936 bool need_bh_off = !(hardirq_count() | softirq_count()); 4937 int ret; 4938 4939 if (need_bh_off) 4940 local_bh_disable(); 4941 trace_netif_rx_entry(skb); 4942 ret = netif_rx_internal(skb); 4943 trace_netif_rx_exit(ret); 4944 if (need_bh_off) 4945 local_bh_enable(); 4946 return ret; 4947 } 4948 EXPORT_SYMBOL(netif_rx); 4949 4950 static __latent_entropy void net_tx_action(struct softirq_action *h) 4951 { 4952 struct softnet_data *sd = this_cpu_ptr(&softnet_data); 4953 4954 if (sd->completion_queue) { 4955 struct sk_buff *clist; 4956 4957 local_irq_disable(); 4958 clist = sd->completion_queue; 4959 sd->completion_queue = NULL; 4960 local_irq_enable(); 4961 4962 while (clist) { 4963 struct sk_buff *skb = clist; 4964 4965 clist = clist->next; 4966 4967 WARN_ON(refcount_read(&skb->users)); 4968 if (likely(get_kfree_skb_cb(skb)->reason == SKB_CONSUMED)) 4969 trace_consume_skb(skb, net_tx_action); 4970 else 4971 trace_kfree_skb(skb, net_tx_action, 4972 get_kfree_skb_cb(skb)->reason); 4973 4974 if (skb->fclone != SKB_FCLONE_UNAVAILABLE) 4975 __kfree_skb(skb); 4976 else 4977 __napi_kfree_skb(skb, 4978 get_kfree_skb_cb(skb)->reason); 4979 } 4980 } 4981 4982 if (sd->output_queue) { 4983 struct Qdisc *head; 4984 4985 local_irq_disable(); 4986 head = sd->output_queue; 4987 sd->output_queue = NULL; 4988 sd->output_queue_tailp = &sd->output_queue; 4989 local_irq_enable(); 4990 4991 rcu_read_lock(); 4992 4993 while (head) { 4994 struct Qdisc *q = head; 4995 spinlock_t *root_lock = NULL; 4996 4997 head = head->next_sched; 4998 4999 /* We need to make sure head->next_sched is read 5000 * before clearing __QDISC_STATE_SCHED 5001 */ 5002 smp_mb__before_atomic(); 5003 5004 if (!(q->flags & TCQ_F_NOLOCK)) { 5005 root_lock = qdisc_lock(q); 5006 spin_lock(root_lock); 5007 } else if (unlikely(test_bit(__QDISC_STATE_DEACTIVATED, 5008 &q->state))) { 5009 /* There is a synchronize_net() between 5010 * STATE_DEACTIVATED flag being set and 5011 * qdisc_reset()/some_qdisc_is_busy() in 5012 * dev_deactivate(), so we can safely bail out 5013 * early here to avoid data race between 5014 * qdisc_deactivate() and some_qdisc_is_busy() 5015 * for lockless qdisc. 5016 */ 5017 clear_bit(__QDISC_STATE_SCHED, &q->state); 5018 continue; 5019 } 5020 5021 clear_bit(__QDISC_STATE_SCHED, &q->state); 5022 qdisc_run(q); 5023 if (root_lock) 5024 spin_unlock(root_lock); 5025 } 5026 5027 rcu_read_unlock(); 5028 } 5029 5030 xfrm_dev_backlog(sd); 5031 } 5032 5033 #if IS_ENABLED(CONFIG_BRIDGE) && IS_ENABLED(CONFIG_ATM_LANE) 5034 /* This hook is defined here for ATM LANE */ 5035 int (*br_fdb_test_addr_hook)(struct net_device *dev, 5036 unsigned char *addr) __read_mostly; 5037 EXPORT_SYMBOL_GPL(br_fdb_test_addr_hook); 5038 #endif 5039 5040 static inline struct sk_buff * 5041 sch_handle_ingress(struct sk_buff *skb, struct packet_type **pt_prev, int *ret, 5042 struct net_device *orig_dev, bool *another) 5043 { 5044 #ifdef CONFIG_NET_CLS_ACT 5045 struct mini_Qdisc *miniq = rcu_dereference_bh(skb->dev->miniq_ingress); 5046 struct tcf_result cl_res; 5047 5048 /* If there's at least one ingress present somewhere (so 5049 * we get here via enabled static key), remaining devices 5050 * that are not configured with an ingress qdisc will bail 5051 * out here. 5052 */ 5053 if (!miniq) 5054 return skb; 5055 5056 if (*pt_prev) { 5057 *ret = deliver_skb(skb, *pt_prev, orig_dev); 5058 *pt_prev = NULL; 5059 } 5060 5061 qdisc_skb_cb(skb)->pkt_len = skb->len; 5062 tc_skb_cb(skb)->mru = 0; 5063 tc_skb_cb(skb)->post_ct = false; 5064 skb->tc_at_ingress = 1; 5065 mini_qdisc_bstats_cpu_update(miniq, skb); 5066 5067 switch (tcf_classify(skb, miniq->block, miniq->filter_list, &cl_res, false)) { 5068 case TC_ACT_OK: 5069 case TC_ACT_RECLASSIFY: 5070 skb->tc_index = TC_H_MIN(cl_res.classid); 5071 break; 5072 case TC_ACT_SHOT: 5073 mini_qdisc_qstats_cpu_drop(miniq); 5074 kfree_skb_reason(skb, SKB_DROP_REASON_TC_INGRESS); 5075 *ret = NET_RX_DROP; 5076 return NULL; 5077 case TC_ACT_STOLEN: 5078 case TC_ACT_QUEUED: 5079 case TC_ACT_TRAP: 5080 consume_skb(skb); 5081 *ret = NET_RX_SUCCESS; 5082 return NULL; 5083 case TC_ACT_REDIRECT: 5084 /* skb_mac_header check was done by cls/act_bpf, so 5085 * we can safely push the L2 header back before 5086 * redirecting to another netdev 5087 */ 5088 __skb_push(skb, skb->mac_len); 5089 if (skb_do_redirect(skb) == -EAGAIN) { 5090 __skb_pull(skb, skb->mac_len); 5091 *another = true; 5092 break; 5093 } 5094 *ret = NET_RX_SUCCESS; 5095 return NULL; 5096 case TC_ACT_CONSUMED: 5097 *ret = NET_RX_SUCCESS; 5098 return NULL; 5099 default: 5100 break; 5101 } 5102 #endif /* CONFIG_NET_CLS_ACT */ 5103 return skb; 5104 } 5105 5106 /** 5107 * netdev_is_rx_handler_busy - check if receive handler is registered 5108 * @dev: device to check 5109 * 5110 * Check if a receive handler is already registered for a given device. 5111 * Return true if there one. 5112 * 5113 * The caller must hold the rtnl_mutex. 5114 */ 5115 bool netdev_is_rx_handler_busy(struct net_device *dev) 5116 { 5117 ASSERT_RTNL(); 5118 return dev && rtnl_dereference(dev->rx_handler); 5119 } 5120 EXPORT_SYMBOL_GPL(netdev_is_rx_handler_busy); 5121 5122 /** 5123 * netdev_rx_handler_register - register receive handler 5124 * @dev: device to register a handler for 5125 * @rx_handler: receive handler to register 5126 * @rx_handler_data: data pointer that is used by rx handler 5127 * 5128 * Register a receive handler for a device. This handler will then be 5129 * called from __netif_receive_skb. A negative errno code is returned 5130 * on a failure. 5131 * 5132 * The caller must hold the rtnl_mutex. 5133 * 5134 * For a general description of rx_handler, see enum rx_handler_result. 5135 */ 5136 int netdev_rx_handler_register(struct net_device *dev, 5137 rx_handler_func_t *rx_handler, 5138 void *rx_handler_data) 5139 { 5140 if (netdev_is_rx_handler_busy(dev)) 5141 return -EBUSY; 5142 5143 if (dev->priv_flags & IFF_NO_RX_HANDLER) 5144 return -EINVAL; 5145 5146 /* Note: rx_handler_data must be set before rx_handler */ 5147 rcu_assign_pointer(dev->rx_handler_data, rx_handler_data); 5148 rcu_assign_pointer(dev->rx_handler, rx_handler); 5149 5150 return 0; 5151 } 5152 EXPORT_SYMBOL_GPL(netdev_rx_handler_register); 5153 5154 /** 5155 * netdev_rx_handler_unregister - unregister receive handler 5156 * @dev: device to unregister a handler from 5157 * 5158 * Unregister a receive handler from a device. 5159 * 5160 * The caller must hold the rtnl_mutex. 5161 */ 5162 void netdev_rx_handler_unregister(struct net_device *dev) 5163 { 5164 5165 ASSERT_RTNL(); 5166 RCU_INIT_POINTER(dev->rx_handler, NULL); 5167 /* a reader seeing a non NULL rx_handler in a rcu_read_lock() 5168 * section has a guarantee to see a non NULL rx_handler_data 5169 * as well. 5170 */ 5171 synchronize_net(); 5172 RCU_INIT_POINTER(dev->rx_handler_data, NULL); 5173 } 5174 EXPORT_SYMBOL_GPL(netdev_rx_handler_unregister); 5175 5176 /* 5177 * Limit the use of PFMEMALLOC reserves to those protocols that implement 5178 * the special handling of PFMEMALLOC skbs. 5179 */ 5180 static bool skb_pfmemalloc_protocol(struct sk_buff *skb) 5181 { 5182 switch (skb->protocol) { 5183 case htons(ETH_P_ARP): 5184 case htons(ETH_P_IP): 5185 case htons(ETH_P_IPV6): 5186 case htons(ETH_P_8021Q): 5187 case htons(ETH_P_8021AD): 5188 return true; 5189 default: 5190 return false; 5191 } 5192 } 5193 5194 static inline int nf_ingress(struct sk_buff *skb, struct packet_type **pt_prev, 5195 int *ret, struct net_device *orig_dev) 5196 { 5197 if (nf_hook_ingress_active(skb)) { 5198 int ingress_retval; 5199 5200 if (*pt_prev) { 5201 *ret = deliver_skb(skb, *pt_prev, orig_dev); 5202 *pt_prev = NULL; 5203 } 5204 5205 rcu_read_lock(); 5206 ingress_retval = nf_hook_ingress(skb); 5207 rcu_read_unlock(); 5208 return ingress_retval; 5209 } 5210 return 0; 5211 } 5212 5213 static int __netif_receive_skb_core(struct sk_buff **pskb, bool pfmemalloc, 5214 struct packet_type **ppt_prev) 5215 { 5216 struct packet_type *ptype, *pt_prev; 5217 rx_handler_func_t *rx_handler; 5218 struct sk_buff *skb = *pskb; 5219 struct net_device *orig_dev; 5220 bool deliver_exact = false; 5221 int ret = NET_RX_DROP; 5222 __be16 type; 5223 5224 net_timestamp_check(!READ_ONCE(netdev_tstamp_prequeue), skb); 5225 5226 trace_netif_receive_skb(skb); 5227 5228 orig_dev = skb->dev; 5229 5230 skb_reset_network_header(skb); 5231 if (!skb_transport_header_was_set(skb)) 5232 skb_reset_transport_header(skb); 5233 skb_reset_mac_len(skb); 5234 5235 pt_prev = NULL; 5236 5237 another_round: 5238 skb->skb_iif = skb->dev->ifindex; 5239 5240 __this_cpu_inc(softnet_data.processed); 5241 5242 if (static_branch_unlikely(&generic_xdp_needed_key)) { 5243 int ret2; 5244 5245 migrate_disable(); 5246 ret2 = do_xdp_generic(rcu_dereference(skb->dev->xdp_prog), skb); 5247 migrate_enable(); 5248 5249 if (ret2 != XDP_PASS) { 5250 ret = NET_RX_DROP; 5251 goto out; 5252 } 5253 } 5254 5255 if (eth_type_vlan(skb->protocol)) { 5256 skb = skb_vlan_untag(skb); 5257 if (unlikely(!skb)) 5258 goto out; 5259 } 5260 5261 if (skb_skip_tc_classify(skb)) 5262 goto skip_classify; 5263 5264 if (pfmemalloc) 5265 goto skip_taps; 5266 5267 list_for_each_entry_rcu(ptype, &ptype_all, list) { 5268 if (pt_prev) 5269 ret = deliver_skb(skb, pt_prev, orig_dev); 5270 pt_prev = ptype; 5271 } 5272 5273 list_for_each_entry_rcu(ptype, &skb->dev->ptype_all, list) { 5274 if (pt_prev) 5275 ret = deliver_skb(skb, pt_prev, orig_dev); 5276 pt_prev = ptype; 5277 } 5278 5279 skip_taps: 5280 #ifdef CONFIG_NET_INGRESS 5281 if (static_branch_unlikely(&ingress_needed_key)) { 5282 bool another = false; 5283 5284 nf_skip_egress(skb, true); 5285 skb = sch_handle_ingress(skb, &pt_prev, &ret, orig_dev, 5286 &another); 5287 if (another) 5288 goto another_round; 5289 if (!skb) 5290 goto out; 5291 5292 nf_skip_egress(skb, false); 5293 if (nf_ingress(skb, &pt_prev, &ret, orig_dev) < 0) 5294 goto out; 5295 } 5296 #endif 5297 skb_reset_redirect(skb); 5298 skip_classify: 5299 if (pfmemalloc && !skb_pfmemalloc_protocol(skb)) 5300 goto drop; 5301 5302 if (skb_vlan_tag_present(skb)) { 5303 if (pt_prev) { 5304 ret = deliver_skb(skb, pt_prev, orig_dev); 5305 pt_prev = NULL; 5306 } 5307 if (vlan_do_receive(&skb)) 5308 goto another_round; 5309 else if (unlikely(!skb)) 5310 goto out; 5311 } 5312 5313 rx_handler = rcu_dereference(skb->dev->rx_handler); 5314 if (rx_handler) { 5315 if (pt_prev) { 5316 ret = deliver_skb(skb, pt_prev, orig_dev); 5317 pt_prev = NULL; 5318 } 5319 switch (rx_handler(&skb)) { 5320 case RX_HANDLER_CONSUMED: 5321 ret = NET_RX_SUCCESS; 5322 goto out; 5323 case RX_HANDLER_ANOTHER: 5324 goto another_round; 5325 case RX_HANDLER_EXACT: 5326 deliver_exact = true; 5327 break; 5328 case RX_HANDLER_PASS: 5329 break; 5330 default: 5331 BUG(); 5332 } 5333 } 5334 5335 if (unlikely(skb_vlan_tag_present(skb)) && !netdev_uses_dsa(skb->dev)) { 5336 check_vlan_id: 5337 if (skb_vlan_tag_get_id(skb)) { 5338 /* Vlan id is non 0 and vlan_do_receive() above couldn't 5339 * find vlan device. 5340 */ 5341 skb->pkt_type = PACKET_OTHERHOST; 5342 } else if (eth_type_vlan(skb->protocol)) { 5343 /* Outer header is 802.1P with vlan 0, inner header is 5344 * 802.1Q or 802.1AD and vlan_do_receive() above could 5345 * not find vlan dev for vlan id 0. 5346 */ 5347 __vlan_hwaccel_clear_tag(skb); 5348 skb = skb_vlan_untag(skb); 5349 if (unlikely(!skb)) 5350 goto out; 5351 if (vlan_do_receive(&skb)) 5352 /* After stripping off 802.1P header with vlan 0 5353 * vlan dev is found for inner header. 5354 */ 5355 goto another_round; 5356 else if (unlikely(!skb)) 5357 goto out; 5358 else 5359 /* We have stripped outer 802.1P vlan 0 header. 5360 * But could not find vlan dev. 5361 * check again for vlan id to set OTHERHOST. 5362 */ 5363 goto check_vlan_id; 5364 } 5365 /* Note: we might in the future use prio bits 5366 * and set skb->priority like in vlan_do_receive() 5367 * For the time being, just ignore Priority Code Point 5368 */ 5369 __vlan_hwaccel_clear_tag(skb); 5370 } 5371 5372 type = skb->protocol; 5373 5374 /* deliver only exact match when indicated */ 5375 if (likely(!deliver_exact)) { 5376 deliver_ptype_list_skb(skb, &pt_prev, orig_dev, type, 5377 &ptype_base[ntohs(type) & 5378 PTYPE_HASH_MASK]); 5379 } 5380 5381 deliver_ptype_list_skb(skb, &pt_prev, orig_dev, type, 5382 &orig_dev->ptype_specific); 5383 5384 if (unlikely(skb->dev != orig_dev)) { 5385 deliver_ptype_list_skb(skb, &pt_prev, orig_dev, type, 5386 &skb->dev->ptype_specific); 5387 } 5388 5389 if (pt_prev) { 5390 if (unlikely(skb_orphan_frags_rx(skb, GFP_ATOMIC))) 5391 goto drop; 5392 *ppt_prev = pt_prev; 5393 } else { 5394 drop: 5395 if (!deliver_exact) 5396 dev_core_stats_rx_dropped_inc(skb->dev); 5397 else 5398 dev_core_stats_rx_nohandler_inc(skb->dev); 5399 kfree_skb_reason(skb, SKB_DROP_REASON_UNHANDLED_PROTO); 5400 /* Jamal, now you will not able to escape explaining 5401 * me how you were going to use this. :-) 5402 */ 5403 ret = NET_RX_DROP; 5404 } 5405 5406 out: 5407 /* The invariant here is that if *ppt_prev is not NULL 5408 * then skb should also be non-NULL. 5409 * 5410 * Apparently *ppt_prev assignment above holds this invariant due to 5411 * skb dereferencing near it. 5412 */ 5413 *pskb = skb; 5414 return ret; 5415 } 5416 5417 static int __netif_receive_skb_one_core(struct sk_buff *skb, bool pfmemalloc) 5418 { 5419 struct net_device *orig_dev = skb->dev; 5420 struct packet_type *pt_prev = NULL; 5421 int ret; 5422 5423 ret = __netif_receive_skb_core(&skb, pfmemalloc, &pt_prev); 5424 if (pt_prev) 5425 ret = INDIRECT_CALL_INET(pt_prev->func, ipv6_rcv, ip_rcv, skb, 5426 skb->dev, pt_prev, orig_dev); 5427 return ret; 5428 } 5429 5430 /** 5431 * netif_receive_skb_core - special purpose version of netif_receive_skb 5432 * @skb: buffer to process 5433 * 5434 * More direct receive version of netif_receive_skb(). It should 5435 * only be used by callers that have a need to skip RPS and Generic XDP. 5436 * Caller must also take care of handling if ``(page_is_)pfmemalloc``. 5437 * 5438 * This function may only be called from softirq context and interrupts 5439 * should be enabled. 5440 * 5441 * Return values (usually ignored): 5442 * NET_RX_SUCCESS: no congestion 5443 * NET_RX_DROP: packet was dropped 5444 */ 5445 int netif_receive_skb_core(struct sk_buff *skb) 5446 { 5447 int ret; 5448 5449 rcu_read_lock(); 5450 ret = __netif_receive_skb_one_core(skb, false); 5451 rcu_read_unlock(); 5452 5453 return ret; 5454 } 5455 EXPORT_SYMBOL(netif_receive_skb_core); 5456 5457 static inline void __netif_receive_skb_list_ptype(struct list_head *head, 5458 struct packet_type *pt_prev, 5459 struct net_device *orig_dev) 5460 { 5461 struct sk_buff *skb, *next; 5462 5463 if (!pt_prev) 5464 return; 5465 if (list_empty(head)) 5466 return; 5467 if (pt_prev->list_func != NULL) 5468 INDIRECT_CALL_INET(pt_prev->list_func, ipv6_list_rcv, 5469 ip_list_rcv, head, pt_prev, orig_dev); 5470 else 5471 list_for_each_entry_safe(skb, next, head, list) { 5472 skb_list_del_init(skb); 5473 pt_prev->func(skb, skb->dev, pt_prev, orig_dev); 5474 } 5475 } 5476 5477 static void __netif_receive_skb_list_core(struct list_head *head, bool pfmemalloc) 5478 { 5479 /* Fast-path assumptions: 5480 * - There is no RX handler. 5481 * - Only one packet_type matches. 5482 * If either of these fails, we will end up doing some per-packet 5483 * processing in-line, then handling the 'last ptype' for the whole 5484 * sublist. This can't cause out-of-order delivery to any single ptype, 5485 * because the 'last ptype' must be constant across the sublist, and all 5486 * other ptypes are handled per-packet. 5487 */ 5488 /* Current (common) ptype of sublist */ 5489 struct packet_type *pt_curr = NULL; 5490 /* Current (common) orig_dev of sublist */ 5491 struct net_device *od_curr = NULL; 5492 struct list_head sublist; 5493 struct sk_buff *skb, *next; 5494 5495 INIT_LIST_HEAD(&sublist); 5496 list_for_each_entry_safe(skb, next, head, list) { 5497 struct net_device *orig_dev = skb->dev; 5498 struct packet_type *pt_prev = NULL; 5499 5500 skb_list_del_init(skb); 5501 __netif_receive_skb_core(&skb, pfmemalloc, &pt_prev); 5502 if (!pt_prev) 5503 continue; 5504 if (pt_curr != pt_prev || od_curr != orig_dev) { 5505 /* dispatch old sublist */ 5506 __netif_receive_skb_list_ptype(&sublist, pt_curr, od_curr); 5507 /* start new sublist */ 5508 INIT_LIST_HEAD(&sublist); 5509 pt_curr = pt_prev; 5510 od_curr = orig_dev; 5511 } 5512 list_add_tail(&skb->list, &sublist); 5513 } 5514 5515 /* dispatch final sublist */ 5516 __netif_receive_skb_list_ptype(&sublist, pt_curr, od_curr); 5517 } 5518 5519 static int __netif_receive_skb(struct sk_buff *skb) 5520 { 5521 int ret; 5522 5523 if (sk_memalloc_socks() && skb_pfmemalloc(skb)) { 5524 unsigned int noreclaim_flag; 5525 5526 /* 5527 * PFMEMALLOC skbs are special, they should 5528 * - be delivered to SOCK_MEMALLOC sockets only 5529 * - stay away from userspace 5530 * - have bounded memory usage 5531 * 5532 * Use PF_MEMALLOC as this saves us from propagating the allocation 5533 * context down to all allocation sites. 5534 */ 5535 noreclaim_flag = memalloc_noreclaim_save(); 5536 ret = __netif_receive_skb_one_core(skb, true); 5537 memalloc_noreclaim_restore(noreclaim_flag); 5538 } else 5539 ret = __netif_receive_skb_one_core(skb, false); 5540 5541 return ret; 5542 } 5543 5544 static void __netif_receive_skb_list(struct list_head *head) 5545 { 5546 unsigned long noreclaim_flag = 0; 5547 struct sk_buff *skb, *next; 5548 bool pfmemalloc = false; /* Is current sublist PF_MEMALLOC? */ 5549 5550 list_for_each_entry_safe(skb, next, head, list) { 5551 if ((sk_memalloc_socks() && skb_pfmemalloc(skb)) != pfmemalloc) { 5552 struct list_head sublist; 5553 5554 /* Handle the previous sublist */ 5555 list_cut_before(&sublist, head, &skb->list); 5556 if (!list_empty(&sublist)) 5557 __netif_receive_skb_list_core(&sublist, pfmemalloc); 5558 pfmemalloc = !pfmemalloc; 5559 /* See comments in __netif_receive_skb */ 5560 if (pfmemalloc) 5561 noreclaim_flag = memalloc_noreclaim_save(); 5562 else 5563 memalloc_noreclaim_restore(noreclaim_flag); 5564 } 5565 } 5566 /* Handle the remaining sublist */ 5567 if (!list_empty(head)) 5568 __netif_receive_skb_list_core(head, pfmemalloc); 5569 /* Restore pflags */ 5570 if (pfmemalloc) 5571 memalloc_noreclaim_restore(noreclaim_flag); 5572 } 5573 5574 static int generic_xdp_install(struct net_device *dev, struct netdev_bpf *xdp) 5575 { 5576 struct bpf_prog *old = rtnl_dereference(dev->xdp_prog); 5577 struct bpf_prog *new = xdp->prog; 5578 int ret = 0; 5579 5580 switch (xdp->command) { 5581 case XDP_SETUP_PROG: 5582 rcu_assign_pointer(dev->xdp_prog, new); 5583 if (old) 5584 bpf_prog_put(old); 5585 5586 if (old && !new) { 5587 static_branch_dec(&generic_xdp_needed_key); 5588 } else if (new && !old) { 5589 static_branch_inc(&generic_xdp_needed_key); 5590 dev_disable_lro(dev); 5591 dev_disable_gro_hw(dev); 5592 } 5593 break; 5594 5595 default: 5596 ret = -EINVAL; 5597 break; 5598 } 5599 5600 return ret; 5601 } 5602 5603 static int netif_receive_skb_internal(struct sk_buff *skb) 5604 { 5605 int ret; 5606 5607 net_timestamp_check(READ_ONCE(netdev_tstamp_prequeue), skb); 5608 5609 if (skb_defer_rx_timestamp(skb)) 5610 return NET_RX_SUCCESS; 5611 5612 rcu_read_lock(); 5613 #ifdef CONFIG_RPS 5614 if (static_branch_unlikely(&rps_needed)) { 5615 struct rps_dev_flow voidflow, *rflow = &voidflow; 5616 int cpu = get_rps_cpu(skb->dev, skb, &rflow); 5617 5618 if (cpu >= 0) { 5619 ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail); 5620 rcu_read_unlock(); 5621 return ret; 5622 } 5623 } 5624 #endif 5625 ret = __netif_receive_skb(skb); 5626 rcu_read_unlock(); 5627 return ret; 5628 } 5629 5630 void netif_receive_skb_list_internal(struct list_head *head) 5631 { 5632 struct sk_buff *skb, *next; 5633 struct list_head sublist; 5634 5635 INIT_LIST_HEAD(&sublist); 5636 list_for_each_entry_safe(skb, next, head, list) { 5637 net_timestamp_check(READ_ONCE(netdev_tstamp_prequeue), skb); 5638 skb_list_del_init(skb); 5639 if (!skb_defer_rx_timestamp(skb)) 5640 list_add_tail(&skb->list, &sublist); 5641 } 5642 list_splice_init(&sublist, head); 5643 5644 rcu_read_lock(); 5645 #ifdef CONFIG_RPS 5646 if (static_branch_unlikely(&rps_needed)) { 5647 list_for_each_entry_safe(skb, next, head, list) { 5648 struct rps_dev_flow voidflow, *rflow = &voidflow; 5649 int cpu = get_rps_cpu(skb->dev, skb, &rflow); 5650 5651 if (cpu >= 0) { 5652 /* Will be handled, remove from list */ 5653 skb_list_del_init(skb); 5654 enqueue_to_backlog(skb, cpu, &rflow->last_qtail); 5655 } 5656 } 5657 } 5658 #endif 5659 __netif_receive_skb_list(head); 5660 rcu_read_unlock(); 5661 } 5662 5663 /** 5664 * netif_receive_skb - process receive buffer from network 5665 * @skb: buffer to process 5666 * 5667 * netif_receive_skb() is the main receive data processing function. 5668 * It always succeeds. The buffer may be dropped during processing 5669 * for congestion control or by the protocol layers. 5670 * 5671 * This function may only be called from softirq context and interrupts 5672 * should be enabled. 5673 * 5674 * Return values (usually ignored): 5675 * NET_RX_SUCCESS: no congestion 5676 * NET_RX_DROP: packet was dropped 5677 */ 5678 int netif_receive_skb(struct sk_buff *skb) 5679 { 5680 int ret; 5681 5682 trace_netif_receive_skb_entry(skb); 5683 5684 ret = netif_receive_skb_internal(skb); 5685 trace_netif_receive_skb_exit(ret); 5686 5687 return ret; 5688 } 5689 EXPORT_SYMBOL(netif_receive_skb); 5690 5691 /** 5692 * netif_receive_skb_list - process many receive buffers from network 5693 * @head: list of skbs to process. 5694 * 5695 * Since return value of netif_receive_skb() is normally ignored, and 5696 * wouldn't be meaningful for a list, this function returns void. 5697 * 5698 * This function may only be called from softirq context and interrupts 5699 * should be enabled. 5700 */ 5701 void netif_receive_skb_list(struct list_head *head) 5702 { 5703 struct sk_buff *skb; 5704 5705 if (list_empty(head)) 5706 return; 5707 if (trace_netif_receive_skb_list_entry_enabled()) { 5708 list_for_each_entry(skb, head, list) 5709 trace_netif_receive_skb_list_entry(skb); 5710 } 5711 netif_receive_skb_list_internal(head); 5712 trace_netif_receive_skb_list_exit(0); 5713 } 5714 EXPORT_SYMBOL(netif_receive_skb_list); 5715 5716 static DEFINE_PER_CPU(struct work_struct, flush_works); 5717 5718 /* Network device is going away, flush any packets still pending */ 5719 static void flush_backlog(struct work_struct *work) 5720 { 5721 struct sk_buff *skb, *tmp; 5722 struct softnet_data *sd; 5723 5724 local_bh_disable(); 5725 sd = this_cpu_ptr(&softnet_data); 5726 5727 rps_lock_irq_disable(sd); 5728 skb_queue_walk_safe(&sd->input_pkt_queue, skb, tmp) { 5729 if (skb->dev->reg_state == NETREG_UNREGISTERING) { 5730 __skb_unlink(skb, &sd->input_pkt_queue); 5731 dev_kfree_skb_irq(skb); 5732 input_queue_head_incr(sd); 5733 } 5734 } 5735 rps_unlock_irq_enable(sd); 5736 5737 skb_queue_walk_safe(&sd->process_queue, skb, tmp) { 5738 if (skb->dev->reg_state == NETREG_UNREGISTERING) { 5739 __skb_unlink(skb, &sd->process_queue); 5740 kfree_skb(skb); 5741 input_queue_head_incr(sd); 5742 } 5743 } 5744 local_bh_enable(); 5745 } 5746 5747 static bool flush_required(int cpu) 5748 { 5749 #if IS_ENABLED(CONFIG_RPS) 5750 struct softnet_data *sd = &per_cpu(softnet_data, cpu); 5751 bool do_flush; 5752 5753 rps_lock_irq_disable(sd); 5754 5755 /* as insertion into process_queue happens with the rps lock held, 5756 * process_queue access may race only with dequeue 5757 */ 5758 do_flush = !skb_queue_empty(&sd->input_pkt_queue) || 5759 !skb_queue_empty_lockless(&sd->process_queue); 5760 rps_unlock_irq_enable(sd); 5761 5762 return do_flush; 5763 #endif 5764 /* without RPS we can't safely check input_pkt_queue: during a 5765 * concurrent remote skb_queue_splice() we can detect as empty both 5766 * input_pkt_queue and process_queue even if the latter could end-up 5767 * containing a lot of packets. 5768 */ 5769 return true; 5770 } 5771 5772 static void flush_all_backlogs(void) 5773 { 5774 static cpumask_t flush_cpus; 5775 unsigned int cpu; 5776 5777 /* since we are under rtnl lock protection we can use static data 5778 * for the cpumask and avoid allocating on stack the possibly 5779 * large mask 5780 */ 5781 ASSERT_RTNL(); 5782 5783 cpus_read_lock(); 5784 5785 cpumask_clear(&flush_cpus); 5786 for_each_online_cpu(cpu) { 5787 if (flush_required(cpu)) { 5788 queue_work_on(cpu, system_highpri_wq, 5789 per_cpu_ptr(&flush_works, cpu)); 5790 cpumask_set_cpu(cpu, &flush_cpus); 5791 } 5792 } 5793 5794 /* we can have in flight packet[s] on the cpus we are not flushing, 5795 * synchronize_net() in unregister_netdevice_many() will take care of 5796 * them 5797 */ 5798 for_each_cpu(cpu, &flush_cpus) 5799 flush_work(per_cpu_ptr(&flush_works, cpu)); 5800 5801 cpus_read_unlock(); 5802 } 5803 5804 static void net_rps_send_ipi(struct softnet_data *remsd) 5805 { 5806 #ifdef CONFIG_RPS 5807 while (remsd) { 5808 struct softnet_data *next = remsd->rps_ipi_next; 5809 5810 if (cpu_online(remsd->cpu)) 5811 smp_call_function_single_async(remsd->cpu, &remsd->csd); 5812 remsd = next; 5813 } 5814 #endif 5815 } 5816 5817 /* 5818 * net_rps_action_and_irq_enable sends any pending IPI's for rps. 5819 * Note: called with local irq disabled, but exits with local irq enabled. 5820 */ 5821 static void net_rps_action_and_irq_enable(struct softnet_data *sd) 5822 { 5823 #ifdef CONFIG_RPS 5824 struct softnet_data *remsd = sd->rps_ipi_list; 5825 5826 if (remsd) { 5827 sd->rps_ipi_list = NULL; 5828 5829 local_irq_enable(); 5830 5831 /* Send pending IPI's to kick RPS processing on remote cpus. */ 5832 net_rps_send_ipi(remsd); 5833 } else 5834 #endif 5835 local_irq_enable(); 5836 } 5837 5838 static bool sd_has_rps_ipi_waiting(struct softnet_data *sd) 5839 { 5840 #ifdef CONFIG_RPS 5841 return sd->rps_ipi_list != NULL; 5842 #else 5843 return false; 5844 #endif 5845 } 5846 5847 static int process_backlog(struct napi_struct *napi, int quota) 5848 { 5849 struct softnet_data *sd = container_of(napi, struct softnet_data, backlog); 5850 bool again = true; 5851 int work = 0; 5852 5853 /* Check if we have pending ipi, its better to send them now, 5854 * not waiting net_rx_action() end. 5855 */ 5856 if (sd_has_rps_ipi_waiting(sd)) { 5857 local_irq_disable(); 5858 net_rps_action_and_irq_enable(sd); 5859 } 5860 5861 napi->weight = READ_ONCE(dev_rx_weight); 5862 while (again) { 5863 struct sk_buff *skb; 5864 5865 while ((skb = __skb_dequeue(&sd->process_queue))) { 5866 rcu_read_lock(); 5867 __netif_receive_skb(skb); 5868 rcu_read_unlock(); 5869 input_queue_head_incr(sd); 5870 if (++work >= quota) 5871 return work; 5872 5873 } 5874 5875 rps_lock_irq_disable(sd); 5876 if (skb_queue_empty(&sd->input_pkt_queue)) { 5877 /* 5878 * Inline a custom version of __napi_complete(). 5879 * only current cpu owns and manipulates this napi, 5880 * and NAPI_STATE_SCHED is the only possible flag set 5881 * on backlog. 5882 * We can use a plain write instead of clear_bit(), 5883 * and we dont need an smp_mb() memory barrier. 5884 */ 5885 napi->state = 0; 5886 again = false; 5887 } else { 5888 skb_queue_splice_tail_init(&sd->input_pkt_queue, 5889 &sd->process_queue); 5890 } 5891 rps_unlock_irq_enable(sd); 5892 } 5893 5894 return work; 5895 } 5896 5897 /** 5898 * __napi_schedule - schedule for receive 5899 * @n: entry to schedule 5900 * 5901 * The entry's receive function will be scheduled to run. 5902 * Consider using __napi_schedule_irqoff() if hard irqs are masked. 5903 */ 5904 void __napi_schedule(struct napi_struct *n) 5905 { 5906 unsigned long flags; 5907 5908 local_irq_save(flags); 5909 ____napi_schedule(this_cpu_ptr(&softnet_data), n); 5910 local_irq_restore(flags); 5911 } 5912 EXPORT_SYMBOL(__napi_schedule); 5913 5914 /** 5915 * napi_schedule_prep - check if napi can be scheduled 5916 * @n: napi context 5917 * 5918 * Test if NAPI routine is already running, and if not mark 5919 * it as running. This is used as a condition variable to 5920 * insure only one NAPI poll instance runs. We also make 5921 * sure there is no pending NAPI disable. 5922 */ 5923 bool napi_schedule_prep(struct napi_struct *n) 5924 { 5925 unsigned long new, val = READ_ONCE(n->state); 5926 5927 do { 5928 if (unlikely(val & NAPIF_STATE_DISABLE)) 5929 return false; 5930 new = val | NAPIF_STATE_SCHED; 5931 5932 /* Sets STATE_MISSED bit if STATE_SCHED was already set 5933 * This was suggested by Alexander Duyck, as compiler 5934 * emits better code than : 5935 * if (val & NAPIF_STATE_SCHED) 5936 * new |= NAPIF_STATE_MISSED; 5937 */ 5938 new |= (val & NAPIF_STATE_SCHED) / NAPIF_STATE_SCHED * 5939 NAPIF_STATE_MISSED; 5940 } while (!try_cmpxchg(&n->state, &val, new)); 5941 5942 return !(val & NAPIF_STATE_SCHED); 5943 } 5944 EXPORT_SYMBOL(napi_schedule_prep); 5945 5946 /** 5947 * __napi_schedule_irqoff - schedule for receive 5948 * @n: entry to schedule 5949 * 5950 * Variant of __napi_schedule() assuming hard irqs are masked. 5951 * 5952 * On PREEMPT_RT enabled kernels this maps to __napi_schedule() 5953 * because the interrupt disabled assumption might not be true 5954 * due to force-threaded interrupts and spinlock substitution. 5955 */ 5956 void __napi_schedule_irqoff(struct napi_struct *n) 5957 { 5958 if (!IS_ENABLED(CONFIG_PREEMPT_RT)) 5959 ____napi_schedule(this_cpu_ptr(&softnet_data), n); 5960 else 5961 __napi_schedule(n); 5962 } 5963 EXPORT_SYMBOL(__napi_schedule_irqoff); 5964 5965 bool napi_complete_done(struct napi_struct *n, int work_done) 5966 { 5967 unsigned long flags, val, new, timeout = 0; 5968 bool ret = true; 5969 5970 /* 5971 * 1) Don't let napi dequeue from the cpu poll list 5972 * just in case its running on a different cpu. 5973 * 2) If we are busy polling, do nothing here, we have 5974 * the guarantee we will be called later. 5975 */ 5976 if (unlikely(n->state & (NAPIF_STATE_NPSVC | 5977 NAPIF_STATE_IN_BUSY_POLL))) 5978 return false; 5979 5980 if (work_done) { 5981 if (n->gro_bitmask) 5982 timeout = READ_ONCE(n->dev->gro_flush_timeout); 5983 n->defer_hard_irqs_count = READ_ONCE(n->dev->napi_defer_hard_irqs); 5984 } 5985 if (n->defer_hard_irqs_count > 0) { 5986 n->defer_hard_irqs_count--; 5987 timeout = READ_ONCE(n->dev->gro_flush_timeout); 5988 if (timeout) 5989 ret = false; 5990 } 5991 if (n->gro_bitmask) { 5992 /* When the NAPI instance uses a timeout and keeps postponing 5993 * it, we need to bound somehow the time packets are kept in 5994 * the GRO layer 5995 */ 5996 napi_gro_flush(n, !!timeout); 5997 } 5998 5999 gro_normal_list(n); 6000 6001 if (unlikely(!list_empty(&n->poll_list))) { 6002 /* If n->poll_list is not empty, we need to mask irqs */ 6003 local_irq_save(flags); 6004 list_del_init(&n->poll_list); 6005 local_irq_restore(flags); 6006 } 6007 WRITE_ONCE(n->list_owner, -1); 6008 6009 val = READ_ONCE(n->state); 6010 do { 6011 WARN_ON_ONCE(!(val & NAPIF_STATE_SCHED)); 6012 6013 new = val & ~(NAPIF_STATE_MISSED | NAPIF_STATE_SCHED | 6014 NAPIF_STATE_SCHED_THREADED | 6015 NAPIF_STATE_PREFER_BUSY_POLL); 6016 6017 /* If STATE_MISSED was set, leave STATE_SCHED set, 6018 * because we will call napi->poll() one more time. 6019 * This C code was suggested by Alexander Duyck to help gcc. 6020 */ 6021 new |= (val & NAPIF_STATE_MISSED) / NAPIF_STATE_MISSED * 6022 NAPIF_STATE_SCHED; 6023 } while (!try_cmpxchg(&n->state, &val, new)); 6024 6025 if (unlikely(val & NAPIF_STATE_MISSED)) { 6026 __napi_schedule(n); 6027 return false; 6028 } 6029 6030 if (timeout) 6031 hrtimer_start(&n->timer, ns_to_ktime(timeout), 6032 HRTIMER_MODE_REL_PINNED); 6033 return ret; 6034 } 6035 EXPORT_SYMBOL(napi_complete_done); 6036 6037 /* must be called under rcu_read_lock(), as we dont take a reference */ 6038 static struct napi_struct *napi_by_id(unsigned int napi_id) 6039 { 6040 unsigned int hash = napi_id % HASH_SIZE(napi_hash); 6041 struct napi_struct *napi; 6042 6043 hlist_for_each_entry_rcu(napi, &napi_hash[hash], napi_hash_node) 6044 if (napi->napi_id == napi_id) 6045 return napi; 6046 6047 return NULL; 6048 } 6049 6050 #if defined(CONFIG_NET_RX_BUSY_POLL) 6051 6052 static void __busy_poll_stop(struct napi_struct *napi, bool skip_schedule) 6053 { 6054 if (!skip_schedule) { 6055 gro_normal_list(napi); 6056 __napi_schedule(napi); 6057 return; 6058 } 6059 6060 if (napi->gro_bitmask) { 6061 /* flush too old packets 6062 * If HZ < 1000, flush all packets. 6063 */ 6064 napi_gro_flush(napi, HZ >= 1000); 6065 } 6066 6067 gro_normal_list(napi); 6068 clear_bit(NAPI_STATE_SCHED, &napi->state); 6069 } 6070 6071 static void busy_poll_stop(struct napi_struct *napi, void *have_poll_lock, bool prefer_busy_poll, 6072 u16 budget) 6073 { 6074 bool skip_schedule = false; 6075 unsigned long timeout; 6076 int rc; 6077 6078 /* Busy polling means there is a high chance device driver hard irq 6079 * could not grab NAPI_STATE_SCHED, and that NAPI_STATE_MISSED was 6080 * set in napi_schedule_prep(). 6081 * Since we are about to call napi->poll() once more, we can safely 6082 * clear NAPI_STATE_MISSED. 6083 * 6084 * Note: x86 could use a single "lock and ..." instruction 6085 * to perform these two clear_bit() 6086 */ 6087 clear_bit(NAPI_STATE_MISSED, &napi->state); 6088 clear_bit(NAPI_STATE_IN_BUSY_POLL, &napi->state); 6089 6090 local_bh_disable(); 6091 6092 if (prefer_busy_poll) { 6093 napi->defer_hard_irqs_count = READ_ONCE(napi->dev->napi_defer_hard_irqs); 6094 timeout = READ_ONCE(napi->dev->gro_flush_timeout); 6095 if (napi->defer_hard_irqs_count && timeout) { 6096 hrtimer_start(&napi->timer, ns_to_ktime(timeout), HRTIMER_MODE_REL_PINNED); 6097 skip_schedule = true; 6098 } 6099 } 6100 6101 /* All we really want here is to re-enable device interrupts. 6102 * Ideally, a new ndo_busy_poll_stop() could avoid another round. 6103 */ 6104 rc = napi->poll(napi, budget); 6105 /* We can't gro_normal_list() here, because napi->poll() might have 6106 * rearmed the napi (napi_complete_done()) in which case it could 6107 * already be running on another CPU. 6108 */ 6109 trace_napi_poll(napi, rc, budget); 6110 netpoll_poll_unlock(have_poll_lock); 6111 if (rc == budget) 6112 __busy_poll_stop(napi, skip_schedule); 6113 local_bh_enable(); 6114 } 6115 6116 void napi_busy_loop(unsigned int napi_id, 6117 bool (*loop_end)(void *, unsigned long), 6118 void *loop_end_arg, bool prefer_busy_poll, u16 budget) 6119 { 6120 unsigned long start_time = loop_end ? busy_loop_current_time() : 0; 6121 int (*napi_poll)(struct napi_struct *napi, int budget); 6122 void *have_poll_lock = NULL; 6123 struct napi_struct *napi; 6124 6125 restart: 6126 napi_poll = NULL; 6127 6128 rcu_read_lock(); 6129 6130 napi = napi_by_id(napi_id); 6131 if (!napi) 6132 goto out; 6133 6134 if (!IS_ENABLED(CONFIG_PREEMPT_RT)) 6135 preempt_disable(); 6136 for (;;) { 6137 int work = 0; 6138 6139 local_bh_disable(); 6140 if (!napi_poll) { 6141 unsigned long val = READ_ONCE(napi->state); 6142 6143 /* If multiple threads are competing for this napi, 6144 * we avoid dirtying napi->state as much as we can. 6145 */ 6146 if (val & (NAPIF_STATE_DISABLE | NAPIF_STATE_SCHED | 6147 NAPIF_STATE_IN_BUSY_POLL)) { 6148 if (prefer_busy_poll) 6149 set_bit(NAPI_STATE_PREFER_BUSY_POLL, &napi->state); 6150 goto count; 6151 } 6152 if (cmpxchg(&napi->state, val, 6153 val | NAPIF_STATE_IN_BUSY_POLL | 6154 NAPIF_STATE_SCHED) != val) { 6155 if (prefer_busy_poll) 6156 set_bit(NAPI_STATE_PREFER_BUSY_POLL, &napi->state); 6157 goto count; 6158 } 6159 have_poll_lock = netpoll_poll_lock(napi); 6160 napi_poll = napi->poll; 6161 } 6162 work = napi_poll(napi, budget); 6163 trace_napi_poll(napi, work, budget); 6164 gro_normal_list(napi); 6165 count: 6166 if (work > 0) 6167 __NET_ADD_STATS(dev_net(napi->dev), 6168 LINUX_MIB_BUSYPOLLRXPACKETS, work); 6169 local_bh_enable(); 6170 6171 if (!loop_end || loop_end(loop_end_arg, start_time)) 6172 break; 6173 6174 if (unlikely(need_resched())) { 6175 if (napi_poll) 6176 busy_poll_stop(napi, have_poll_lock, prefer_busy_poll, budget); 6177 if (!IS_ENABLED(CONFIG_PREEMPT_RT)) 6178 preempt_enable(); 6179 rcu_read_unlock(); 6180 cond_resched(); 6181 if (loop_end(loop_end_arg, start_time)) 6182 return; 6183 goto restart; 6184 } 6185 cpu_relax(); 6186 } 6187 if (napi_poll) 6188 busy_poll_stop(napi, have_poll_lock, prefer_busy_poll, budget); 6189 if (!IS_ENABLED(CONFIG_PREEMPT_RT)) 6190 preempt_enable(); 6191 out: 6192 rcu_read_unlock(); 6193 } 6194 EXPORT_SYMBOL(napi_busy_loop); 6195 6196 #endif /* CONFIG_NET_RX_BUSY_POLL */ 6197 6198 static void napi_hash_add(struct napi_struct *napi) 6199 { 6200 if (test_bit(NAPI_STATE_NO_BUSY_POLL, &napi->state)) 6201 return; 6202 6203 spin_lock(&napi_hash_lock); 6204 6205 /* 0..NR_CPUS range is reserved for sender_cpu use */ 6206 do { 6207 if (unlikely(++napi_gen_id < MIN_NAPI_ID)) 6208 napi_gen_id = MIN_NAPI_ID; 6209 } while (napi_by_id(napi_gen_id)); 6210 napi->napi_id = napi_gen_id; 6211 6212 hlist_add_head_rcu(&napi->napi_hash_node, 6213 &napi_hash[napi->napi_id % HASH_SIZE(napi_hash)]); 6214 6215 spin_unlock(&napi_hash_lock); 6216 } 6217 6218 /* Warning : caller is responsible to make sure rcu grace period 6219 * is respected before freeing memory containing @napi 6220 */ 6221 static void napi_hash_del(struct napi_struct *napi) 6222 { 6223 spin_lock(&napi_hash_lock); 6224 6225 hlist_del_init_rcu(&napi->napi_hash_node); 6226 6227 spin_unlock(&napi_hash_lock); 6228 } 6229 6230 static enum hrtimer_restart napi_watchdog(struct hrtimer *timer) 6231 { 6232 struct napi_struct *napi; 6233 6234 napi = container_of(timer, struct napi_struct, timer); 6235 6236 /* Note : we use a relaxed variant of napi_schedule_prep() not setting 6237 * NAPI_STATE_MISSED, since we do not react to a device IRQ. 6238 */ 6239 if (!napi_disable_pending(napi) && 6240 !test_and_set_bit(NAPI_STATE_SCHED, &napi->state)) { 6241 clear_bit(NAPI_STATE_PREFER_BUSY_POLL, &napi->state); 6242 __napi_schedule_irqoff(napi); 6243 } 6244 6245 return HRTIMER_NORESTART; 6246 } 6247 6248 static void init_gro_hash(struct napi_struct *napi) 6249 { 6250 int i; 6251 6252 for (i = 0; i < GRO_HASH_BUCKETS; i++) { 6253 INIT_LIST_HEAD(&napi->gro_hash[i].list); 6254 napi->gro_hash[i].count = 0; 6255 } 6256 napi->gro_bitmask = 0; 6257 } 6258 6259 int dev_set_threaded(struct net_device *dev, bool threaded) 6260 { 6261 struct napi_struct *napi; 6262 int err = 0; 6263 6264 if (dev->threaded == threaded) 6265 return 0; 6266 6267 if (threaded) { 6268 list_for_each_entry(napi, &dev->napi_list, dev_list) { 6269 if (!napi->thread) { 6270 err = napi_kthread_create(napi); 6271 if (err) { 6272 threaded = false; 6273 break; 6274 } 6275 } 6276 } 6277 } 6278 6279 dev->threaded = threaded; 6280 6281 /* Make sure kthread is created before THREADED bit 6282 * is set. 6283 */ 6284 smp_mb__before_atomic(); 6285 6286 /* Setting/unsetting threaded mode on a napi might not immediately 6287 * take effect, if the current napi instance is actively being 6288 * polled. In this case, the switch between threaded mode and 6289 * softirq mode will happen in the next round of napi_schedule(). 6290 * This should not cause hiccups/stalls to the live traffic. 6291 */ 6292 list_for_each_entry(napi, &dev->napi_list, dev_list) { 6293 if (threaded) 6294 set_bit(NAPI_STATE_THREADED, &napi->state); 6295 else 6296 clear_bit(NAPI_STATE_THREADED, &napi->state); 6297 } 6298 6299 return err; 6300 } 6301 EXPORT_SYMBOL(dev_set_threaded); 6302 6303 void netif_napi_add_weight(struct net_device *dev, struct napi_struct *napi, 6304 int (*poll)(struct napi_struct *, int), int weight) 6305 { 6306 if (WARN_ON(test_and_set_bit(NAPI_STATE_LISTED, &napi->state))) 6307 return; 6308 6309 INIT_LIST_HEAD(&napi->poll_list); 6310 INIT_HLIST_NODE(&napi->napi_hash_node); 6311 hrtimer_init(&napi->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_PINNED); 6312 napi->timer.function = napi_watchdog; 6313 init_gro_hash(napi); 6314 napi->skb = NULL; 6315 INIT_LIST_HEAD(&napi->rx_list); 6316 napi->rx_count = 0; 6317 napi->poll = poll; 6318 if (weight > NAPI_POLL_WEIGHT) 6319 netdev_err_once(dev, "%s() called with weight %d\n", __func__, 6320 weight); 6321 napi->weight = weight; 6322 napi->dev = dev; 6323 #ifdef CONFIG_NETPOLL 6324 napi->poll_owner = -1; 6325 #endif 6326 napi->list_owner = -1; 6327 set_bit(NAPI_STATE_SCHED, &napi->state); 6328 set_bit(NAPI_STATE_NPSVC, &napi->state); 6329 list_add_rcu(&napi->dev_list, &dev->napi_list); 6330 napi_hash_add(napi); 6331 napi_get_frags_check(napi); 6332 /* Create kthread for this napi if dev->threaded is set. 6333 * Clear dev->threaded if kthread creation failed so that 6334 * threaded mode will not be enabled in napi_enable(). 6335 */ 6336 if (dev->threaded && napi_kthread_create(napi)) 6337 dev->threaded = 0; 6338 } 6339 EXPORT_SYMBOL(netif_napi_add_weight); 6340 6341 void napi_disable(struct napi_struct *n) 6342 { 6343 unsigned long val, new; 6344 6345 might_sleep(); 6346 set_bit(NAPI_STATE_DISABLE, &n->state); 6347 6348 val = READ_ONCE(n->state); 6349 do { 6350 while (val & (NAPIF_STATE_SCHED | NAPIF_STATE_NPSVC)) { 6351 usleep_range(20, 200); 6352 val = READ_ONCE(n->state); 6353 } 6354 6355 new = val | NAPIF_STATE_SCHED | NAPIF_STATE_NPSVC; 6356 new &= ~(NAPIF_STATE_THREADED | NAPIF_STATE_PREFER_BUSY_POLL); 6357 } while (!try_cmpxchg(&n->state, &val, new)); 6358 6359 hrtimer_cancel(&n->timer); 6360 6361 clear_bit(NAPI_STATE_DISABLE, &n->state); 6362 } 6363 EXPORT_SYMBOL(napi_disable); 6364 6365 /** 6366 * napi_enable - enable NAPI scheduling 6367 * @n: NAPI context 6368 * 6369 * Resume NAPI from being scheduled on this context. 6370 * Must be paired with napi_disable. 6371 */ 6372 void napi_enable(struct napi_struct *n) 6373 { 6374 unsigned long new, val = READ_ONCE(n->state); 6375 6376 do { 6377 BUG_ON(!test_bit(NAPI_STATE_SCHED, &val)); 6378 6379 new = val & ~(NAPIF_STATE_SCHED | NAPIF_STATE_NPSVC); 6380 if (n->dev->threaded && n->thread) 6381 new |= NAPIF_STATE_THREADED; 6382 } while (!try_cmpxchg(&n->state, &val, new)); 6383 } 6384 EXPORT_SYMBOL(napi_enable); 6385 6386 static void flush_gro_hash(struct napi_struct *napi) 6387 { 6388 int i; 6389 6390 for (i = 0; i < GRO_HASH_BUCKETS; i++) { 6391 struct sk_buff *skb, *n; 6392 6393 list_for_each_entry_safe(skb, n, &napi->gro_hash[i].list, list) 6394 kfree_skb(skb); 6395 napi->gro_hash[i].count = 0; 6396 } 6397 } 6398 6399 /* Must be called in process context */ 6400 void __netif_napi_del(struct napi_struct *napi) 6401 { 6402 if (!test_and_clear_bit(NAPI_STATE_LISTED, &napi->state)) 6403 return; 6404 6405 napi_hash_del(napi); 6406 list_del_rcu(&napi->dev_list); 6407 napi_free_frags(napi); 6408 6409 flush_gro_hash(napi); 6410 napi->gro_bitmask = 0; 6411 6412 if (napi->thread) { 6413 kthread_stop(napi->thread); 6414 napi->thread = NULL; 6415 } 6416 } 6417 EXPORT_SYMBOL(__netif_napi_del); 6418 6419 static int __napi_poll(struct napi_struct *n, bool *repoll) 6420 { 6421 int work, weight; 6422 6423 weight = n->weight; 6424 6425 /* This NAPI_STATE_SCHED test is for avoiding a race 6426 * with netpoll's poll_napi(). Only the entity which 6427 * obtains the lock and sees NAPI_STATE_SCHED set will 6428 * actually make the ->poll() call. Therefore we avoid 6429 * accidentally calling ->poll() when NAPI is not scheduled. 6430 */ 6431 work = 0; 6432 if (test_bit(NAPI_STATE_SCHED, &n->state)) { 6433 work = n->poll(n, weight); 6434 trace_napi_poll(n, work, weight); 6435 } 6436 6437 if (unlikely(work > weight)) 6438 netdev_err_once(n->dev, "NAPI poll function %pS returned %d, exceeding its budget of %d.\n", 6439 n->poll, work, weight); 6440 6441 if (likely(work < weight)) 6442 return work; 6443 6444 /* Drivers must not modify the NAPI state if they 6445 * consume the entire weight. In such cases this code 6446 * still "owns" the NAPI instance and therefore can 6447 * move the instance around on the list at-will. 6448 */ 6449 if (unlikely(napi_disable_pending(n))) { 6450 napi_complete(n); 6451 return work; 6452 } 6453 6454 /* The NAPI context has more processing work, but busy-polling 6455 * is preferred. Exit early. 6456 */ 6457 if (napi_prefer_busy_poll(n)) { 6458 if (napi_complete_done(n, work)) { 6459 /* If timeout is not set, we need to make sure 6460 * that the NAPI is re-scheduled. 6461 */ 6462 napi_schedule(n); 6463 } 6464 return work; 6465 } 6466 6467 if (n->gro_bitmask) { 6468 /* flush too old packets 6469 * If HZ < 1000, flush all packets. 6470 */ 6471 napi_gro_flush(n, HZ >= 1000); 6472 } 6473 6474 gro_normal_list(n); 6475 6476 /* Some drivers may have called napi_schedule 6477 * prior to exhausting their budget. 6478 */ 6479 if (unlikely(!list_empty(&n->poll_list))) { 6480 pr_warn_once("%s: Budget exhausted after napi rescheduled\n", 6481 n->dev ? n->dev->name : "backlog"); 6482 return work; 6483 } 6484 6485 *repoll = true; 6486 6487 return work; 6488 } 6489 6490 static int napi_poll(struct napi_struct *n, struct list_head *repoll) 6491 { 6492 bool do_repoll = false; 6493 void *have; 6494 int work; 6495 6496 list_del_init(&n->poll_list); 6497 6498 have = netpoll_poll_lock(n); 6499 6500 work = __napi_poll(n, &do_repoll); 6501 6502 if (do_repoll) 6503 list_add_tail(&n->poll_list, repoll); 6504 6505 netpoll_poll_unlock(have); 6506 6507 return work; 6508 } 6509 6510 static int napi_thread_wait(struct napi_struct *napi) 6511 { 6512 bool woken = false; 6513 6514 set_current_state(TASK_INTERRUPTIBLE); 6515 6516 while (!kthread_should_stop()) { 6517 /* Testing SCHED_THREADED bit here to make sure the current 6518 * kthread owns this napi and could poll on this napi. 6519 * Testing SCHED bit is not enough because SCHED bit might be 6520 * set by some other busy poll thread or by napi_disable(). 6521 */ 6522 if (test_bit(NAPI_STATE_SCHED_THREADED, &napi->state) || woken) { 6523 WARN_ON(!list_empty(&napi->poll_list)); 6524 __set_current_state(TASK_RUNNING); 6525 return 0; 6526 } 6527 6528 schedule(); 6529 /* woken being true indicates this thread owns this napi. */ 6530 woken = true; 6531 set_current_state(TASK_INTERRUPTIBLE); 6532 } 6533 __set_current_state(TASK_RUNNING); 6534 6535 return -1; 6536 } 6537 6538 static void skb_defer_free_flush(struct softnet_data *sd) 6539 { 6540 struct sk_buff *skb, *next; 6541 6542 /* Paired with WRITE_ONCE() in skb_attempt_defer_free() */ 6543 if (!READ_ONCE(sd->defer_list)) 6544 return; 6545 6546 spin_lock(&sd->defer_lock); 6547 skb = sd->defer_list; 6548 sd->defer_list = NULL; 6549 sd->defer_count = 0; 6550 spin_unlock(&sd->defer_lock); 6551 6552 while (skb != NULL) { 6553 next = skb->next; 6554 napi_consume_skb(skb, 1); 6555 skb = next; 6556 } 6557 } 6558 6559 static int napi_threaded_poll(void *data) 6560 { 6561 struct napi_struct *napi = data; 6562 struct softnet_data *sd; 6563 void *have; 6564 6565 while (!napi_thread_wait(napi)) { 6566 for (;;) { 6567 bool repoll = false; 6568 6569 local_bh_disable(); 6570 sd = this_cpu_ptr(&softnet_data); 6571 sd->in_napi_threaded_poll = true; 6572 6573 have = netpoll_poll_lock(napi); 6574 __napi_poll(napi, &repoll); 6575 netpoll_poll_unlock(have); 6576 6577 sd->in_napi_threaded_poll = false; 6578 barrier(); 6579 6580 if (sd_has_rps_ipi_waiting(sd)) { 6581 local_irq_disable(); 6582 net_rps_action_and_irq_enable(sd); 6583 } 6584 skb_defer_free_flush(sd); 6585 local_bh_enable(); 6586 6587 if (!repoll) 6588 break; 6589 6590 cond_resched(); 6591 } 6592 } 6593 return 0; 6594 } 6595 6596 static __latent_entropy void net_rx_action(struct softirq_action *h) 6597 { 6598 struct softnet_data *sd = this_cpu_ptr(&softnet_data); 6599 unsigned long time_limit = jiffies + 6600 usecs_to_jiffies(READ_ONCE(netdev_budget_usecs)); 6601 int budget = READ_ONCE(netdev_budget); 6602 LIST_HEAD(list); 6603 LIST_HEAD(repoll); 6604 6605 start: 6606 sd->in_net_rx_action = true; 6607 local_irq_disable(); 6608 list_splice_init(&sd->poll_list, &list); 6609 local_irq_enable(); 6610 6611 for (;;) { 6612 struct napi_struct *n; 6613 6614 skb_defer_free_flush(sd); 6615 6616 if (list_empty(&list)) { 6617 if (list_empty(&repoll)) { 6618 sd->in_net_rx_action = false; 6619 barrier(); 6620 /* We need to check if ____napi_schedule() 6621 * had refilled poll_list while 6622 * sd->in_net_rx_action was true. 6623 */ 6624 if (!list_empty(&sd->poll_list)) 6625 goto start; 6626 if (!sd_has_rps_ipi_waiting(sd)) 6627 goto end; 6628 } 6629 break; 6630 } 6631 6632 n = list_first_entry(&list, struct napi_struct, poll_list); 6633 budget -= napi_poll(n, &repoll); 6634 6635 /* If softirq window is exhausted then punt. 6636 * Allow this to run for 2 jiffies since which will allow 6637 * an average latency of 1.5/HZ. 6638 */ 6639 if (unlikely(budget <= 0 || 6640 time_after_eq(jiffies, time_limit))) { 6641 sd->time_squeeze++; 6642 break; 6643 } 6644 } 6645 6646 local_irq_disable(); 6647 6648 list_splice_tail_init(&sd->poll_list, &list); 6649 list_splice_tail(&repoll, &list); 6650 list_splice(&list, &sd->poll_list); 6651 if (!list_empty(&sd->poll_list)) 6652 __raise_softirq_irqoff(NET_RX_SOFTIRQ); 6653 else 6654 sd->in_net_rx_action = false; 6655 6656 net_rps_action_and_irq_enable(sd); 6657 end:; 6658 } 6659 6660 struct netdev_adjacent { 6661 struct net_device *dev; 6662 netdevice_tracker dev_tracker; 6663 6664 /* upper master flag, there can only be one master device per list */ 6665 bool master; 6666 6667 /* lookup ignore flag */ 6668 bool ignore; 6669 6670 /* counter for the number of times this device was added to us */ 6671 u16 ref_nr; 6672 6673 /* private field for the users */ 6674 void *private; 6675 6676 struct list_head list; 6677 struct rcu_head rcu; 6678 }; 6679 6680 static struct netdev_adjacent *__netdev_find_adj(struct net_device *adj_dev, 6681 struct list_head *adj_list) 6682 { 6683 struct netdev_adjacent *adj; 6684 6685 list_for_each_entry(adj, adj_list, list) { 6686 if (adj->dev == adj_dev) 6687 return adj; 6688 } 6689 return NULL; 6690 } 6691 6692 static int ____netdev_has_upper_dev(struct net_device *upper_dev, 6693 struct netdev_nested_priv *priv) 6694 { 6695 struct net_device *dev = (struct net_device *)priv->data; 6696 6697 return upper_dev == dev; 6698 } 6699 6700 /** 6701 * netdev_has_upper_dev - Check if device is linked to an upper device 6702 * @dev: device 6703 * @upper_dev: upper device to check 6704 * 6705 * Find out if a device is linked to specified upper device and return true 6706 * in case it is. Note that this checks only immediate upper device, 6707 * not through a complete stack of devices. The caller must hold the RTNL lock. 6708 */ 6709 bool netdev_has_upper_dev(struct net_device *dev, 6710 struct net_device *upper_dev) 6711 { 6712 struct netdev_nested_priv priv = { 6713 .data = (void *)upper_dev, 6714 }; 6715 6716 ASSERT_RTNL(); 6717 6718 return netdev_walk_all_upper_dev_rcu(dev, ____netdev_has_upper_dev, 6719 &priv); 6720 } 6721 EXPORT_SYMBOL(netdev_has_upper_dev); 6722 6723 /** 6724 * netdev_has_upper_dev_all_rcu - Check if device is linked to an upper device 6725 * @dev: device 6726 * @upper_dev: upper device to check 6727 * 6728 * Find out if a device is linked to specified upper device and return true 6729 * in case it is. Note that this checks the entire upper device chain. 6730 * The caller must hold rcu lock. 6731 */ 6732 6733 bool netdev_has_upper_dev_all_rcu(struct net_device *dev, 6734 struct net_device *upper_dev) 6735 { 6736 struct netdev_nested_priv priv = { 6737 .data = (void *)upper_dev, 6738 }; 6739 6740 return !!netdev_walk_all_upper_dev_rcu(dev, ____netdev_has_upper_dev, 6741 &priv); 6742 } 6743 EXPORT_SYMBOL(netdev_has_upper_dev_all_rcu); 6744 6745 /** 6746 * netdev_has_any_upper_dev - Check if device is linked to some device 6747 * @dev: device 6748 * 6749 * Find out if a device is linked to an upper device and return true in case 6750 * it is. The caller must hold the RTNL lock. 6751 */ 6752 bool netdev_has_any_upper_dev(struct net_device *dev) 6753 { 6754 ASSERT_RTNL(); 6755 6756 return !list_empty(&dev->adj_list.upper); 6757 } 6758 EXPORT_SYMBOL(netdev_has_any_upper_dev); 6759 6760 /** 6761 * netdev_master_upper_dev_get - Get master upper device 6762 * @dev: device 6763 * 6764 * Find a master upper device and return pointer to it or NULL in case 6765 * it's not there. The caller must hold the RTNL lock. 6766 */ 6767 struct net_device *netdev_master_upper_dev_get(struct net_device *dev) 6768 { 6769 struct netdev_adjacent *upper; 6770 6771 ASSERT_RTNL(); 6772 6773 if (list_empty(&dev->adj_list.upper)) 6774 return NULL; 6775 6776 upper = list_first_entry(&dev->adj_list.upper, 6777 struct netdev_adjacent, list); 6778 if (likely(upper->master)) 6779 return upper->dev; 6780 return NULL; 6781 } 6782 EXPORT_SYMBOL(netdev_master_upper_dev_get); 6783 6784 static struct net_device *__netdev_master_upper_dev_get(struct net_device *dev) 6785 { 6786 struct netdev_adjacent *upper; 6787 6788 ASSERT_RTNL(); 6789 6790 if (list_empty(&dev->adj_list.upper)) 6791 return NULL; 6792 6793 upper = list_first_entry(&dev->adj_list.upper, 6794 struct netdev_adjacent, list); 6795 if (likely(upper->master) && !upper->ignore) 6796 return upper->dev; 6797 return NULL; 6798 } 6799 6800 /** 6801 * netdev_has_any_lower_dev - Check if device is linked to some device 6802 * @dev: device 6803 * 6804 * Find out if a device is linked to a lower device and return true in case 6805 * it is. The caller must hold the RTNL lock. 6806 */ 6807 static bool netdev_has_any_lower_dev(struct net_device *dev) 6808 { 6809 ASSERT_RTNL(); 6810 6811 return !list_empty(&dev->adj_list.lower); 6812 } 6813 6814 void *netdev_adjacent_get_private(struct list_head *adj_list) 6815 { 6816 struct netdev_adjacent *adj; 6817 6818 adj = list_entry(adj_list, struct netdev_adjacent, list); 6819 6820 return adj->private; 6821 } 6822 EXPORT_SYMBOL(netdev_adjacent_get_private); 6823 6824 /** 6825 * netdev_upper_get_next_dev_rcu - Get the next dev from upper list 6826 * @dev: device 6827 * @iter: list_head ** of the current position 6828 * 6829 * Gets the next device from the dev's upper list, starting from iter 6830 * position. The caller must hold RCU read lock. 6831 */ 6832 struct net_device *netdev_upper_get_next_dev_rcu(struct net_device *dev, 6833 struct list_head **iter) 6834 { 6835 struct netdev_adjacent *upper; 6836 6837 WARN_ON_ONCE(!rcu_read_lock_held() && !lockdep_rtnl_is_held()); 6838 6839 upper = list_entry_rcu((*iter)->next, struct netdev_adjacent, list); 6840 6841 if (&upper->list == &dev->adj_list.upper) 6842 return NULL; 6843 6844 *iter = &upper->list; 6845 6846 return upper->dev; 6847 } 6848 EXPORT_SYMBOL(netdev_upper_get_next_dev_rcu); 6849 6850 static struct net_device *__netdev_next_upper_dev(struct net_device *dev, 6851 struct list_head **iter, 6852 bool *ignore) 6853 { 6854 struct netdev_adjacent *upper; 6855 6856 upper = list_entry((*iter)->next, struct netdev_adjacent, list); 6857 6858 if (&upper->list == &dev->adj_list.upper) 6859 return NULL; 6860 6861 *iter = &upper->list; 6862 *ignore = upper->ignore; 6863 6864 return upper->dev; 6865 } 6866 6867 static struct net_device *netdev_next_upper_dev_rcu(struct net_device *dev, 6868 struct list_head **iter) 6869 { 6870 struct netdev_adjacent *upper; 6871 6872 WARN_ON_ONCE(!rcu_read_lock_held() && !lockdep_rtnl_is_held()); 6873 6874 upper = list_entry_rcu((*iter)->next, struct netdev_adjacent, list); 6875 6876 if (&upper->list == &dev->adj_list.upper) 6877 return NULL; 6878 6879 *iter = &upper->list; 6880 6881 return upper->dev; 6882 } 6883 6884 static int __netdev_walk_all_upper_dev(struct net_device *dev, 6885 int (*fn)(struct net_device *dev, 6886 struct netdev_nested_priv *priv), 6887 struct netdev_nested_priv *priv) 6888 { 6889 struct net_device *udev, *next, *now, *dev_stack[MAX_NEST_DEV + 1]; 6890 struct list_head *niter, *iter, *iter_stack[MAX_NEST_DEV + 1]; 6891 int ret, cur = 0; 6892 bool ignore; 6893 6894 now = dev; 6895 iter = &dev->adj_list.upper; 6896 6897 while (1) { 6898 if (now != dev) { 6899 ret = fn(now, priv); 6900 if (ret) 6901 return ret; 6902 } 6903 6904 next = NULL; 6905 while (1) { 6906 udev = __netdev_next_upper_dev(now, &iter, &ignore); 6907 if (!udev) 6908 break; 6909 if (ignore) 6910 continue; 6911 6912 next = udev; 6913 niter = &udev->adj_list.upper; 6914 dev_stack[cur] = now; 6915 iter_stack[cur++] = iter; 6916 break; 6917 } 6918 6919 if (!next) { 6920 if (!cur) 6921 return 0; 6922 next = dev_stack[--cur]; 6923 niter = iter_stack[cur]; 6924 } 6925 6926 now = next; 6927 iter = niter; 6928 } 6929 6930 return 0; 6931 } 6932 6933 int netdev_walk_all_upper_dev_rcu(struct net_device *dev, 6934 int (*fn)(struct net_device *dev, 6935 struct netdev_nested_priv *priv), 6936 struct netdev_nested_priv *priv) 6937 { 6938 struct net_device *udev, *next, *now, *dev_stack[MAX_NEST_DEV + 1]; 6939 struct list_head *niter, *iter, *iter_stack[MAX_NEST_DEV + 1]; 6940 int ret, cur = 0; 6941 6942 now = dev; 6943 iter = &dev->adj_list.upper; 6944 6945 while (1) { 6946 if (now != dev) { 6947 ret = fn(now, priv); 6948 if (ret) 6949 return ret; 6950 } 6951 6952 next = NULL; 6953 while (1) { 6954 udev = netdev_next_upper_dev_rcu(now, &iter); 6955 if (!udev) 6956 break; 6957 6958 next = udev; 6959 niter = &udev->adj_list.upper; 6960 dev_stack[cur] = now; 6961 iter_stack[cur++] = iter; 6962 break; 6963 } 6964 6965 if (!next) { 6966 if (!cur) 6967 return 0; 6968 next = dev_stack[--cur]; 6969 niter = iter_stack[cur]; 6970 } 6971 6972 now = next; 6973 iter = niter; 6974 } 6975 6976 return 0; 6977 } 6978 EXPORT_SYMBOL_GPL(netdev_walk_all_upper_dev_rcu); 6979 6980 static bool __netdev_has_upper_dev(struct net_device *dev, 6981 struct net_device *upper_dev) 6982 { 6983 struct netdev_nested_priv priv = { 6984 .flags = 0, 6985 .data = (void *)upper_dev, 6986 }; 6987 6988 ASSERT_RTNL(); 6989 6990 return __netdev_walk_all_upper_dev(dev, ____netdev_has_upper_dev, 6991 &priv); 6992 } 6993 6994 /** 6995 * netdev_lower_get_next_private - Get the next ->private from the 6996 * lower neighbour list 6997 * @dev: device 6998 * @iter: list_head ** of the current position 6999 * 7000 * Gets the next netdev_adjacent->private from the dev's lower neighbour 7001 * list, starting from iter position. The caller must hold either hold the 7002 * RTNL lock or its own locking that guarantees that the neighbour lower 7003 * list will remain unchanged. 7004 */ 7005 void *netdev_lower_get_next_private(struct net_device *dev, 7006 struct list_head **iter) 7007 { 7008 struct netdev_adjacent *lower; 7009 7010 lower = list_entry(*iter, struct netdev_adjacent, list); 7011 7012 if (&lower->list == &dev->adj_list.lower) 7013 return NULL; 7014 7015 *iter = lower->list.next; 7016 7017 return lower->private; 7018 } 7019 EXPORT_SYMBOL(netdev_lower_get_next_private); 7020 7021 /** 7022 * netdev_lower_get_next_private_rcu - Get the next ->private from the 7023 * lower neighbour list, RCU 7024 * variant 7025 * @dev: device 7026 * @iter: list_head ** of the current position 7027 * 7028 * Gets the next netdev_adjacent->private from the dev's lower neighbour 7029 * list, starting from iter position. The caller must hold RCU read lock. 7030 */ 7031 void *netdev_lower_get_next_private_rcu(struct net_device *dev, 7032 struct list_head **iter) 7033 { 7034 struct netdev_adjacent *lower; 7035 7036 WARN_ON_ONCE(!rcu_read_lock_held() && !rcu_read_lock_bh_held()); 7037 7038 lower = list_entry_rcu((*iter)->next, struct netdev_adjacent, list); 7039 7040 if (&lower->list == &dev->adj_list.lower) 7041 return NULL; 7042 7043 *iter = &lower->list; 7044 7045 return lower->private; 7046 } 7047 EXPORT_SYMBOL(netdev_lower_get_next_private_rcu); 7048 7049 /** 7050 * netdev_lower_get_next - Get the next device from the lower neighbour 7051 * list 7052 * @dev: device 7053 * @iter: list_head ** of the current position 7054 * 7055 * Gets the next netdev_adjacent from the dev's lower neighbour 7056 * list, starting from iter position. The caller must hold RTNL lock or 7057 * its own locking that guarantees that the neighbour lower 7058 * list will remain unchanged. 7059 */ 7060 void *netdev_lower_get_next(struct net_device *dev, struct list_head **iter) 7061 { 7062 struct netdev_adjacent *lower; 7063 7064 lower = list_entry(*iter, struct netdev_adjacent, list); 7065 7066 if (&lower->list == &dev->adj_list.lower) 7067 return NULL; 7068 7069 *iter = lower->list.next; 7070 7071 return lower->dev; 7072 } 7073 EXPORT_SYMBOL(netdev_lower_get_next); 7074 7075 static struct net_device *netdev_next_lower_dev(struct net_device *dev, 7076 struct list_head **iter) 7077 { 7078 struct netdev_adjacent *lower; 7079 7080 lower = list_entry((*iter)->next, struct netdev_adjacent, list); 7081 7082 if (&lower->list == &dev->adj_list.lower) 7083 return NULL; 7084 7085 *iter = &lower->list; 7086 7087 return lower->dev; 7088 } 7089 7090 static struct net_device *__netdev_next_lower_dev(struct net_device *dev, 7091 struct list_head **iter, 7092 bool *ignore) 7093 { 7094 struct netdev_adjacent *lower; 7095 7096 lower = list_entry((*iter)->next, struct netdev_adjacent, list); 7097 7098 if (&lower->list == &dev->adj_list.lower) 7099 return NULL; 7100 7101 *iter = &lower->list; 7102 *ignore = lower->ignore; 7103 7104 return lower->dev; 7105 } 7106 7107 int netdev_walk_all_lower_dev(struct net_device *dev, 7108 int (*fn)(struct net_device *dev, 7109 struct netdev_nested_priv *priv), 7110 struct netdev_nested_priv *priv) 7111 { 7112 struct net_device *ldev, *next, *now, *dev_stack[MAX_NEST_DEV + 1]; 7113 struct list_head *niter, *iter, *iter_stack[MAX_NEST_DEV + 1]; 7114 int ret, cur = 0; 7115 7116 now = dev; 7117 iter = &dev->adj_list.lower; 7118 7119 while (1) { 7120 if (now != dev) { 7121 ret = fn(now, priv); 7122 if (ret) 7123 return ret; 7124 } 7125 7126 next = NULL; 7127 while (1) { 7128 ldev = netdev_next_lower_dev(now, &iter); 7129 if (!ldev) 7130 break; 7131 7132 next = ldev; 7133 niter = &ldev->adj_list.lower; 7134 dev_stack[cur] = now; 7135 iter_stack[cur++] = iter; 7136 break; 7137 } 7138 7139 if (!next) { 7140 if (!cur) 7141 return 0; 7142 next = dev_stack[--cur]; 7143 niter = iter_stack[cur]; 7144 } 7145 7146 now = next; 7147 iter = niter; 7148 } 7149 7150 return 0; 7151 } 7152 EXPORT_SYMBOL_GPL(netdev_walk_all_lower_dev); 7153 7154 static int __netdev_walk_all_lower_dev(struct net_device *dev, 7155 int (*fn)(struct net_device *dev, 7156 struct netdev_nested_priv *priv), 7157 struct netdev_nested_priv *priv) 7158 { 7159 struct net_device *ldev, *next, *now, *dev_stack[MAX_NEST_DEV + 1]; 7160 struct list_head *niter, *iter, *iter_stack[MAX_NEST_DEV + 1]; 7161 int ret, cur = 0; 7162 bool ignore; 7163 7164 now = dev; 7165 iter = &dev->adj_list.lower; 7166 7167 while (1) { 7168 if (now != dev) { 7169 ret = fn(now, priv); 7170 if (ret) 7171 return ret; 7172 } 7173 7174 next = NULL; 7175 while (1) { 7176 ldev = __netdev_next_lower_dev(now, &iter, &ignore); 7177 if (!ldev) 7178 break; 7179 if (ignore) 7180 continue; 7181 7182 next = ldev; 7183 niter = &ldev->adj_list.lower; 7184 dev_stack[cur] = now; 7185 iter_stack[cur++] = iter; 7186 break; 7187 } 7188 7189 if (!next) { 7190 if (!cur) 7191 return 0; 7192 next = dev_stack[--cur]; 7193 niter = iter_stack[cur]; 7194 } 7195 7196 now = next; 7197 iter = niter; 7198 } 7199 7200 return 0; 7201 } 7202 7203 struct net_device *netdev_next_lower_dev_rcu(struct net_device *dev, 7204 struct list_head **iter) 7205 { 7206 struct netdev_adjacent *lower; 7207 7208 lower = list_entry_rcu((*iter)->next, struct netdev_adjacent, list); 7209 if (&lower->list == &dev->adj_list.lower) 7210 return NULL; 7211 7212 *iter = &lower->list; 7213 7214 return lower->dev; 7215 } 7216 EXPORT_SYMBOL(netdev_next_lower_dev_rcu); 7217 7218 static u8 __netdev_upper_depth(struct net_device *dev) 7219 { 7220 struct net_device *udev; 7221 struct list_head *iter; 7222 u8 max_depth = 0; 7223 bool ignore; 7224 7225 for (iter = &dev->adj_list.upper, 7226 udev = __netdev_next_upper_dev(dev, &iter, &ignore); 7227 udev; 7228 udev = __netdev_next_upper_dev(dev, &iter, &ignore)) { 7229 if (ignore) 7230 continue; 7231 if (max_depth < udev->upper_level) 7232 max_depth = udev->upper_level; 7233 } 7234 7235 return max_depth; 7236 } 7237 7238 static u8 __netdev_lower_depth(struct net_device *dev) 7239 { 7240 struct net_device *ldev; 7241 struct list_head *iter; 7242 u8 max_depth = 0; 7243 bool ignore; 7244 7245 for (iter = &dev->adj_list.lower, 7246 ldev = __netdev_next_lower_dev(dev, &iter, &ignore); 7247 ldev; 7248 ldev = __netdev_next_lower_dev(dev, &iter, &ignore)) { 7249 if (ignore) 7250 continue; 7251 if (max_depth < ldev->lower_level) 7252 max_depth = ldev->lower_level; 7253 } 7254 7255 return max_depth; 7256 } 7257 7258 static int __netdev_update_upper_level(struct net_device *dev, 7259 struct netdev_nested_priv *__unused) 7260 { 7261 dev->upper_level = __netdev_upper_depth(dev) + 1; 7262 return 0; 7263 } 7264 7265 #ifdef CONFIG_LOCKDEP 7266 static LIST_HEAD(net_unlink_list); 7267 7268 static void net_unlink_todo(struct net_device *dev) 7269 { 7270 if (list_empty(&dev->unlink_list)) 7271 list_add_tail(&dev->unlink_list, &net_unlink_list); 7272 } 7273 #endif 7274 7275 static int __netdev_update_lower_level(struct net_device *dev, 7276 struct netdev_nested_priv *priv) 7277 { 7278 dev->lower_level = __netdev_lower_depth(dev) + 1; 7279 7280 #ifdef CONFIG_LOCKDEP 7281 if (!priv) 7282 return 0; 7283 7284 if (priv->flags & NESTED_SYNC_IMM) 7285 dev->nested_level = dev->lower_level - 1; 7286 if (priv->flags & NESTED_SYNC_TODO) 7287 net_unlink_todo(dev); 7288 #endif 7289 return 0; 7290 } 7291 7292 int netdev_walk_all_lower_dev_rcu(struct net_device *dev, 7293 int (*fn)(struct net_device *dev, 7294 struct netdev_nested_priv *priv), 7295 struct netdev_nested_priv *priv) 7296 { 7297 struct net_device *ldev, *next, *now, *dev_stack[MAX_NEST_DEV + 1]; 7298 struct list_head *niter, *iter, *iter_stack[MAX_NEST_DEV + 1]; 7299 int ret, cur = 0; 7300 7301 now = dev; 7302 iter = &dev->adj_list.lower; 7303 7304 while (1) { 7305 if (now != dev) { 7306 ret = fn(now, priv); 7307 if (ret) 7308 return ret; 7309 } 7310 7311 next = NULL; 7312 while (1) { 7313 ldev = netdev_next_lower_dev_rcu(now, &iter); 7314 if (!ldev) 7315 break; 7316 7317 next = ldev; 7318 niter = &ldev->adj_list.lower; 7319 dev_stack[cur] = now; 7320 iter_stack[cur++] = iter; 7321 break; 7322 } 7323 7324 if (!next) { 7325 if (!cur) 7326 return 0; 7327 next = dev_stack[--cur]; 7328 niter = iter_stack[cur]; 7329 } 7330 7331 now = next; 7332 iter = niter; 7333 } 7334 7335 return 0; 7336 } 7337 EXPORT_SYMBOL_GPL(netdev_walk_all_lower_dev_rcu); 7338 7339 /** 7340 * netdev_lower_get_first_private_rcu - Get the first ->private from the 7341 * lower neighbour list, RCU 7342 * variant 7343 * @dev: device 7344 * 7345 * Gets the first netdev_adjacent->private from the dev's lower neighbour 7346 * list. The caller must hold RCU read lock. 7347 */ 7348 void *netdev_lower_get_first_private_rcu(struct net_device *dev) 7349 { 7350 struct netdev_adjacent *lower; 7351 7352 lower = list_first_or_null_rcu(&dev->adj_list.lower, 7353 struct netdev_adjacent, list); 7354 if (lower) 7355 return lower->private; 7356 return NULL; 7357 } 7358 EXPORT_SYMBOL(netdev_lower_get_first_private_rcu); 7359 7360 /** 7361 * netdev_master_upper_dev_get_rcu - Get master upper device 7362 * @dev: device 7363 * 7364 * Find a master upper device and return pointer to it or NULL in case 7365 * it's not there. The caller must hold the RCU read lock. 7366 */ 7367 struct net_device *netdev_master_upper_dev_get_rcu(struct net_device *dev) 7368 { 7369 struct netdev_adjacent *upper; 7370 7371 upper = list_first_or_null_rcu(&dev->adj_list.upper, 7372 struct netdev_adjacent, list); 7373 if (upper && likely(upper->master)) 7374 return upper->dev; 7375 return NULL; 7376 } 7377 EXPORT_SYMBOL(netdev_master_upper_dev_get_rcu); 7378 7379 static int netdev_adjacent_sysfs_add(struct net_device *dev, 7380 struct net_device *adj_dev, 7381 struct list_head *dev_list) 7382 { 7383 char linkname[IFNAMSIZ+7]; 7384 7385 sprintf(linkname, dev_list == &dev->adj_list.upper ? 7386 "upper_%s" : "lower_%s", adj_dev->name); 7387 return sysfs_create_link(&(dev->dev.kobj), &(adj_dev->dev.kobj), 7388 linkname); 7389 } 7390 static void netdev_adjacent_sysfs_del(struct net_device *dev, 7391 char *name, 7392 struct list_head *dev_list) 7393 { 7394 char linkname[IFNAMSIZ+7]; 7395 7396 sprintf(linkname, dev_list == &dev->adj_list.upper ? 7397 "upper_%s" : "lower_%s", name); 7398 sysfs_remove_link(&(dev->dev.kobj), linkname); 7399 } 7400 7401 static inline bool netdev_adjacent_is_neigh_list(struct net_device *dev, 7402 struct net_device *adj_dev, 7403 struct list_head *dev_list) 7404 { 7405 return (dev_list == &dev->adj_list.upper || 7406 dev_list == &dev->adj_list.lower) && 7407 net_eq(dev_net(dev), dev_net(adj_dev)); 7408 } 7409 7410 static int __netdev_adjacent_dev_insert(struct net_device *dev, 7411 struct net_device *adj_dev, 7412 struct list_head *dev_list, 7413 void *private, bool master) 7414 { 7415 struct netdev_adjacent *adj; 7416 int ret; 7417 7418 adj = __netdev_find_adj(adj_dev, dev_list); 7419 7420 if (adj) { 7421 adj->ref_nr += 1; 7422 pr_debug("Insert adjacency: dev %s adj_dev %s adj->ref_nr %d\n", 7423 dev->name, adj_dev->name, adj->ref_nr); 7424 7425 return 0; 7426 } 7427 7428 adj = kmalloc(sizeof(*adj), GFP_KERNEL); 7429 if (!adj) 7430 return -ENOMEM; 7431 7432 adj->dev = adj_dev; 7433 adj->master = master; 7434 adj->ref_nr = 1; 7435 adj->private = private; 7436 adj->ignore = false; 7437 netdev_hold(adj_dev, &adj->dev_tracker, GFP_KERNEL); 7438 7439 pr_debug("Insert adjacency: dev %s adj_dev %s adj->ref_nr %d; dev_hold on %s\n", 7440 dev->name, adj_dev->name, adj->ref_nr, adj_dev->name); 7441 7442 if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list)) { 7443 ret = netdev_adjacent_sysfs_add(dev, adj_dev, dev_list); 7444 if (ret) 7445 goto free_adj; 7446 } 7447 7448 /* Ensure that master link is always the first item in list. */ 7449 if (master) { 7450 ret = sysfs_create_link(&(dev->dev.kobj), 7451 &(adj_dev->dev.kobj), "master"); 7452 if (ret) 7453 goto remove_symlinks; 7454 7455 list_add_rcu(&adj->list, dev_list); 7456 } else { 7457 list_add_tail_rcu(&adj->list, dev_list); 7458 } 7459 7460 return 0; 7461 7462 remove_symlinks: 7463 if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list)) 7464 netdev_adjacent_sysfs_del(dev, adj_dev->name, dev_list); 7465 free_adj: 7466 netdev_put(adj_dev, &adj->dev_tracker); 7467 kfree(adj); 7468 7469 return ret; 7470 } 7471 7472 static void __netdev_adjacent_dev_remove(struct net_device *dev, 7473 struct net_device *adj_dev, 7474 u16 ref_nr, 7475 struct list_head *dev_list) 7476 { 7477 struct netdev_adjacent *adj; 7478 7479 pr_debug("Remove adjacency: dev %s adj_dev %s ref_nr %d\n", 7480 dev->name, adj_dev->name, ref_nr); 7481 7482 adj = __netdev_find_adj(adj_dev, dev_list); 7483 7484 if (!adj) { 7485 pr_err("Adjacency does not exist for device %s from %s\n", 7486 dev->name, adj_dev->name); 7487 WARN_ON(1); 7488 return; 7489 } 7490 7491 if (adj->ref_nr > ref_nr) { 7492 pr_debug("adjacency: %s to %s ref_nr - %d = %d\n", 7493 dev->name, adj_dev->name, ref_nr, 7494 adj->ref_nr - ref_nr); 7495 adj->ref_nr -= ref_nr; 7496 return; 7497 } 7498 7499 if (adj->master) 7500 sysfs_remove_link(&(dev->dev.kobj), "master"); 7501 7502 if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list)) 7503 netdev_adjacent_sysfs_del(dev, adj_dev->name, dev_list); 7504 7505 list_del_rcu(&adj->list); 7506 pr_debug("adjacency: dev_put for %s, because link removed from %s to %s\n", 7507 adj_dev->name, dev->name, adj_dev->name); 7508 netdev_put(adj_dev, &adj->dev_tracker); 7509 kfree_rcu(adj, rcu); 7510 } 7511 7512 static int __netdev_adjacent_dev_link_lists(struct net_device *dev, 7513 struct net_device *upper_dev, 7514 struct list_head *up_list, 7515 struct list_head *down_list, 7516 void *private, bool master) 7517 { 7518 int ret; 7519 7520 ret = __netdev_adjacent_dev_insert(dev, upper_dev, up_list, 7521 private, master); 7522 if (ret) 7523 return ret; 7524 7525 ret = __netdev_adjacent_dev_insert(upper_dev, dev, down_list, 7526 private, false); 7527 if (ret) { 7528 __netdev_adjacent_dev_remove(dev, upper_dev, 1, up_list); 7529 return ret; 7530 } 7531 7532 return 0; 7533 } 7534 7535 static void __netdev_adjacent_dev_unlink_lists(struct net_device *dev, 7536 struct net_device *upper_dev, 7537 u16 ref_nr, 7538 struct list_head *up_list, 7539 struct list_head *down_list) 7540 { 7541 __netdev_adjacent_dev_remove(dev, upper_dev, ref_nr, up_list); 7542 __netdev_adjacent_dev_remove(upper_dev, dev, ref_nr, down_list); 7543 } 7544 7545 static int __netdev_adjacent_dev_link_neighbour(struct net_device *dev, 7546 struct net_device *upper_dev, 7547 void *private, bool master) 7548 { 7549 return __netdev_adjacent_dev_link_lists(dev, upper_dev, 7550 &dev->adj_list.upper, 7551 &upper_dev->adj_list.lower, 7552 private, master); 7553 } 7554 7555 static void __netdev_adjacent_dev_unlink_neighbour(struct net_device *dev, 7556 struct net_device *upper_dev) 7557 { 7558 __netdev_adjacent_dev_unlink_lists(dev, upper_dev, 1, 7559 &dev->adj_list.upper, 7560 &upper_dev->adj_list.lower); 7561 } 7562 7563 static int __netdev_upper_dev_link(struct net_device *dev, 7564 struct net_device *upper_dev, bool master, 7565 void *upper_priv, void *upper_info, 7566 struct netdev_nested_priv *priv, 7567 struct netlink_ext_ack *extack) 7568 { 7569 struct netdev_notifier_changeupper_info changeupper_info = { 7570 .info = { 7571 .dev = dev, 7572 .extack = extack, 7573 }, 7574 .upper_dev = upper_dev, 7575 .master = master, 7576 .linking = true, 7577 .upper_info = upper_info, 7578 }; 7579 struct net_device *master_dev; 7580 int ret = 0; 7581 7582 ASSERT_RTNL(); 7583 7584 if (dev == upper_dev) 7585 return -EBUSY; 7586 7587 /* To prevent loops, check if dev is not upper device to upper_dev. */ 7588 if (__netdev_has_upper_dev(upper_dev, dev)) 7589 return -EBUSY; 7590 7591 if ((dev->lower_level + upper_dev->upper_level) > MAX_NEST_DEV) 7592 return -EMLINK; 7593 7594 if (!master) { 7595 if (__netdev_has_upper_dev(dev, upper_dev)) 7596 return -EEXIST; 7597 } else { 7598 master_dev = __netdev_master_upper_dev_get(dev); 7599 if (master_dev) 7600 return master_dev == upper_dev ? -EEXIST : -EBUSY; 7601 } 7602 7603 ret = call_netdevice_notifiers_info(NETDEV_PRECHANGEUPPER, 7604 &changeupper_info.info); 7605 ret = notifier_to_errno(ret); 7606 if (ret) 7607 return ret; 7608 7609 ret = __netdev_adjacent_dev_link_neighbour(dev, upper_dev, upper_priv, 7610 master); 7611 if (ret) 7612 return ret; 7613 7614 ret = call_netdevice_notifiers_info(NETDEV_CHANGEUPPER, 7615 &changeupper_info.info); 7616 ret = notifier_to_errno(ret); 7617 if (ret) 7618 goto rollback; 7619 7620 __netdev_update_upper_level(dev, NULL); 7621 __netdev_walk_all_lower_dev(dev, __netdev_update_upper_level, NULL); 7622 7623 __netdev_update_lower_level(upper_dev, priv); 7624 __netdev_walk_all_upper_dev(upper_dev, __netdev_update_lower_level, 7625 priv); 7626 7627 return 0; 7628 7629 rollback: 7630 __netdev_adjacent_dev_unlink_neighbour(dev, upper_dev); 7631 7632 return ret; 7633 } 7634 7635 /** 7636 * netdev_upper_dev_link - Add a link to the upper device 7637 * @dev: device 7638 * @upper_dev: new upper device 7639 * @extack: netlink extended ack 7640 * 7641 * Adds a link to device which is upper to this one. The caller must hold 7642 * the RTNL lock. On a failure a negative errno code is returned. 7643 * On success the reference counts are adjusted and the function 7644 * returns zero. 7645 */ 7646 int netdev_upper_dev_link(struct net_device *dev, 7647 struct net_device *upper_dev, 7648 struct netlink_ext_ack *extack) 7649 { 7650 struct netdev_nested_priv priv = { 7651 .flags = NESTED_SYNC_IMM | NESTED_SYNC_TODO, 7652 .data = NULL, 7653 }; 7654 7655 return __netdev_upper_dev_link(dev, upper_dev, false, 7656 NULL, NULL, &priv, extack); 7657 } 7658 EXPORT_SYMBOL(netdev_upper_dev_link); 7659 7660 /** 7661 * netdev_master_upper_dev_link - Add a master link to the upper device 7662 * @dev: device 7663 * @upper_dev: new upper device 7664 * @upper_priv: upper device private 7665 * @upper_info: upper info to be passed down via notifier 7666 * @extack: netlink extended ack 7667 * 7668 * Adds a link to device which is upper to this one. In this case, only 7669 * one master upper device can be linked, although other non-master devices 7670 * might be linked as well. The caller must hold the RTNL lock. 7671 * On a failure a negative errno code is returned. On success the reference 7672 * counts are adjusted and the function returns zero. 7673 */ 7674 int netdev_master_upper_dev_link(struct net_device *dev, 7675 struct net_device *upper_dev, 7676 void *upper_priv, void *upper_info, 7677 struct netlink_ext_ack *extack) 7678 { 7679 struct netdev_nested_priv priv = { 7680 .flags = NESTED_SYNC_IMM | NESTED_SYNC_TODO, 7681 .data = NULL, 7682 }; 7683 7684 return __netdev_upper_dev_link(dev, upper_dev, true, 7685 upper_priv, upper_info, &priv, extack); 7686 } 7687 EXPORT_SYMBOL(netdev_master_upper_dev_link); 7688 7689 static void __netdev_upper_dev_unlink(struct net_device *dev, 7690 struct net_device *upper_dev, 7691 struct netdev_nested_priv *priv) 7692 { 7693 struct netdev_notifier_changeupper_info changeupper_info = { 7694 .info = { 7695 .dev = dev, 7696 }, 7697 .upper_dev = upper_dev, 7698 .linking = false, 7699 }; 7700 7701 ASSERT_RTNL(); 7702 7703 changeupper_info.master = netdev_master_upper_dev_get(dev) == upper_dev; 7704 7705 call_netdevice_notifiers_info(NETDEV_PRECHANGEUPPER, 7706 &changeupper_info.info); 7707 7708 __netdev_adjacent_dev_unlink_neighbour(dev, upper_dev); 7709 7710 call_netdevice_notifiers_info(NETDEV_CHANGEUPPER, 7711 &changeupper_info.info); 7712 7713 __netdev_update_upper_level(dev, NULL); 7714 __netdev_walk_all_lower_dev(dev, __netdev_update_upper_level, NULL); 7715 7716 __netdev_update_lower_level(upper_dev, priv); 7717 __netdev_walk_all_upper_dev(upper_dev, __netdev_update_lower_level, 7718 priv); 7719 } 7720 7721 /** 7722 * netdev_upper_dev_unlink - Removes a link to upper device 7723 * @dev: device 7724 * @upper_dev: new upper device 7725 * 7726 * Removes a link to device which is upper to this one. The caller must hold 7727 * the RTNL lock. 7728 */ 7729 void netdev_upper_dev_unlink(struct net_device *dev, 7730 struct net_device *upper_dev) 7731 { 7732 struct netdev_nested_priv priv = { 7733 .flags = NESTED_SYNC_TODO, 7734 .data = NULL, 7735 }; 7736 7737 __netdev_upper_dev_unlink(dev, upper_dev, &priv); 7738 } 7739 EXPORT_SYMBOL(netdev_upper_dev_unlink); 7740 7741 static void __netdev_adjacent_dev_set(struct net_device *upper_dev, 7742 struct net_device *lower_dev, 7743 bool val) 7744 { 7745 struct netdev_adjacent *adj; 7746 7747 adj = __netdev_find_adj(lower_dev, &upper_dev->adj_list.lower); 7748 if (adj) 7749 adj->ignore = val; 7750 7751 adj = __netdev_find_adj(upper_dev, &lower_dev->adj_list.upper); 7752 if (adj) 7753 adj->ignore = val; 7754 } 7755 7756 static void netdev_adjacent_dev_disable(struct net_device *upper_dev, 7757 struct net_device *lower_dev) 7758 { 7759 __netdev_adjacent_dev_set(upper_dev, lower_dev, true); 7760 } 7761 7762 static void netdev_adjacent_dev_enable(struct net_device *upper_dev, 7763 struct net_device *lower_dev) 7764 { 7765 __netdev_adjacent_dev_set(upper_dev, lower_dev, false); 7766 } 7767 7768 int netdev_adjacent_change_prepare(struct net_device *old_dev, 7769 struct net_device *new_dev, 7770 struct net_device *dev, 7771 struct netlink_ext_ack *extack) 7772 { 7773 struct netdev_nested_priv priv = { 7774 .flags = 0, 7775 .data = NULL, 7776 }; 7777 int err; 7778 7779 if (!new_dev) 7780 return 0; 7781 7782 if (old_dev && new_dev != old_dev) 7783 netdev_adjacent_dev_disable(dev, old_dev); 7784 err = __netdev_upper_dev_link(new_dev, dev, false, NULL, NULL, &priv, 7785 extack); 7786 if (err) { 7787 if (old_dev && new_dev != old_dev) 7788 netdev_adjacent_dev_enable(dev, old_dev); 7789 return err; 7790 } 7791 7792 return 0; 7793 } 7794 EXPORT_SYMBOL(netdev_adjacent_change_prepare); 7795 7796 void netdev_adjacent_change_commit(struct net_device *old_dev, 7797 struct net_device *new_dev, 7798 struct net_device *dev) 7799 { 7800 struct netdev_nested_priv priv = { 7801 .flags = NESTED_SYNC_IMM | NESTED_SYNC_TODO, 7802 .data = NULL, 7803 }; 7804 7805 if (!new_dev || !old_dev) 7806 return; 7807 7808 if (new_dev == old_dev) 7809 return; 7810 7811 netdev_adjacent_dev_enable(dev, old_dev); 7812 __netdev_upper_dev_unlink(old_dev, dev, &priv); 7813 } 7814 EXPORT_SYMBOL(netdev_adjacent_change_commit); 7815 7816 void netdev_adjacent_change_abort(struct net_device *old_dev, 7817 struct net_device *new_dev, 7818 struct net_device *dev) 7819 { 7820 struct netdev_nested_priv priv = { 7821 .flags = 0, 7822 .data = NULL, 7823 }; 7824 7825 if (!new_dev) 7826 return; 7827 7828 if (old_dev && new_dev != old_dev) 7829 netdev_adjacent_dev_enable(dev, old_dev); 7830 7831 __netdev_upper_dev_unlink(new_dev, dev, &priv); 7832 } 7833 EXPORT_SYMBOL(netdev_adjacent_change_abort); 7834 7835 /** 7836 * netdev_bonding_info_change - Dispatch event about slave change 7837 * @dev: device 7838 * @bonding_info: info to dispatch 7839 * 7840 * Send NETDEV_BONDING_INFO to netdev notifiers with info. 7841 * The caller must hold the RTNL lock. 7842 */ 7843 void netdev_bonding_info_change(struct net_device *dev, 7844 struct netdev_bonding_info *bonding_info) 7845 { 7846 struct netdev_notifier_bonding_info info = { 7847 .info.dev = dev, 7848 }; 7849 7850 memcpy(&info.bonding_info, bonding_info, 7851 sizeof(struct netdev_bonding_info)); 7852 call_netdevice_notifiers_info(NETDEV_BONDING_INFO, 7853 &info.info); 7854 } 7855 EXPORT_SYMBOL(netdev_bonding_info_change); 7856 7857 static int netdev_offload_xstats_enable_l3(struct net_device *dev, 7858 struct netlink_ext_ack *extack) 7859 { 7860 struct netdev_notifier_offload_xstats_info info = { 7861 .info.dev = dev, 7862 .info.extack = extack, 7863 .type = NETDEV_OFFLOAD_XSTATS_TYPE_L3, 7864 }; 7865 int err; 7866 int rc; 7867 7868 dev->offload_xstats_l3 = kzalloc(sizeof(*dev->offload_xstats_l3), 7869 GFP_KERNEL); 7870 if (!dev->offload_xstats_l3) 7871 return -ENOMEM; 7872 7873 rc = call_netdevice_notifiers_info_robust(NETDEV_OFFLOAD_XSTATS_ENABLE, 7874 NETDEV_OFFLOAD_XSTATS_DISABLE, 7875 &info.info); 7876 err = notifier_to_errno(rc); 7877 if (err) 7878 goto free_stats; 7879 7880 return 0; 7881 7882 free_stats: 7883 kfree(dev->offload_xstats_l3); 7884 dev->offload_xstats_l3 = NULL; 7885 return err; 7886 } 7887 7888 int netdev_offload_xstats_enable(struct net_device *dev, 7889 enum netdev_offload_xstats_type type, 7890 struct netlink_ext_ack *extack) 7891 { 7892 ASSERT_RTNL(); 7893 7894 if (netdev_offload_xstats_enabled(dev, type)) 7895 return -EALREADY; 7896 7897 switch (type) { 7898 case NETDEV_OFFLOAD_XSTATS_TYPE_L3: 7899 return netdev_offload_xstats_enable_l3(dev, extack); 7900 } 7901 7902 WARN_ON(1); 7903 return -EINVAL; 7904 } 7905 EXPORT_SYMBOL(netdev_offload_xstats_enable); 7906 7907 static void netdev_offload_xstats_disable_l3(struct net_device *dev) 7908 { 7909 struct netdev_notifier_offload_xstats_info info = { 7910 .info.dev = dev, 7911 .type = NETDEV_OFFLOAD_XSTATS_TYPE_L3, 7912 }; 7913 7914 call_netdevice_notifiers_info(NETDEV_OFFLOAD_XSTATS_DISABLE, 7915 &info.info); 7916 kfree(dev->offload_xstats_l3); 7917 dev->offload_xstats_l3 = NULL; 7918 } 7919 7920 int netdev_offload_xstats_disable(struct net_device *dev, 7921 enum netdev_offload_xstats_type type) 7922 { 7923 ASSERT_RTNL(); 7924 7925 if (!netdev_offload_xstats_enabled(dev, type)) 7926 return -EALREADY; 7927 7928 switch (type) { 7929 case NETDEV_OFFLOAD_XSTATS_TYPE_L3: 7930 netdev_offload_xstats_disable_l3(dev); 7931 return 0; 7932 } 7933 7934 WARN_ON(1); 7935 return -EINVAL; 7936 } 7937 EXPORT_SYMBOL(netdev_offload_xstats_disable); 7938 7939 static void netdev_offload_xstats_disable_all(struct net_device *dev) 7940 { 7941 netdev_offload_xstats_disable(dev, NETDEV_OFFLOAD_XSTATS_TYPE_L3); 7942 } 7943 7944 static struct rtnl_hw_stats64 * 7945 netdev_offload_xstats_get_ptr(const struct net_device *dev, 7946 enum netdev_offload_xstats_type type) 7947 { 7948 switch (type) { 7949 case NETDEV_OFFLOAD_XSTATS_TYPE_L3: 7950 return dev->offload_xstats_l3; 7951 } 7952 7953 WARN_ON(1); 7954 return NULL; 7955 } 7956 7957 bool netdev_offload_xstats_enabled(const struct net_device *dev, 7958 enum netdev_offload_xstats_type type) 7959 { 7960 ASSERT_RTNL(); 7961 7962 return netdev_offload_xstats_get_ptr(dev, type); 7963 } 7964 EXPORT_SYMBOL(netdev_offload_xstats_enabled); 7965 7966 struct netdev_notifier_offload_xstats_ru { 7967 bool used; 7968 }; 7969 7970 struct netdev_notifier_offload_xstats_rd { 7971 struct rtnl_hw_stats64 stats; 7972 bool used; 7973 }; 7974 7975 static void netdev_hw_stats64_add(struct rtnl_hw_stats64 *dest, 7976 const struct rtnl_hw_stats64 *src) 7977 { 7978 dest->rx_packets += src->rx_packets; 7979 dest->tx_packets += src->tx_packets; 7980 dest->rx_bytes += src->rx_bytes; 7981 dest->tx_bytes += src->tx_bytes; 7982 dest->rx_errors += src->rx_errors; 7983 dest->tx_errors += src->tx_errors; 7984 dest->rx_dropped += src->rx_dropped; 7985 dest->tx_dropped += src->tx_dropped; 7986 dest->multicast += src->multicast; 7987 } 7988 7989 static int netdev_offload_xstats_get_used(struct net_device *dev, 7990 enum netdev_offload_xstats_type type, 7991 bool *p_used, 7992 struct netlink_ext_ack *extack) 7993 { 7994 struct netdev_notifier_offload_xstats_ru report_used = {}; 7995 struct netdev_notifier_offload_xstats_info info = { 7996 .info.dev = dev, 7997 .info.extack = extack, 7998 .type = type, 7999 .report_used = &report_used, 8000 }; 8001 int rc; 8002 8003 WARN_ON(!netdev_offload_xstats_enabled(dev, type)); 8004 rc = call_netdevice_notifiers_info(NETDEV_OFFLOAD_XSTATS_REPORT_USED, 8005 &info.info); 8006 *p_used = report_used.used; 8007 return notifier_to_errno(rc); 8008 } 8009 8010 static int netdev_offload_xstats_get_stats(struct net_device *dev, 8011 enum netdev_offload_xstats_type type, 8012 struct rtnl_hw_stats64 *p_stats, 8013 bool *p_used, 8014 struct netlink_ext_ack *extack) 8015 { 8016 struct netdev_notifier_offload_xstats_rd report_delta = {}; 8017 struct netdev_notifier_offload_xstats_info info = { 8018 .info.dev = dev, 8019 .info.extack = extack, 8020 .type = type, 8021 .report_delta = &report_delta, 8022 }; 8023 struct rtnl_hw_stats64 *stats; 8024 int rc; 8025 8026 stats = netdev_offload_xstats_get_ptr(dev, type); 8027 if (WARN_ON(!stats)) 8028 return -EINVAL; 8029 8030 rc = call_netdevice_notifiers_info(NETDEV_OFFLOAD_XSTATS_REPORT_DELTA, 8031 &info.info); 8032 8033 /* Cache whatever we got, even if there was an error, otherwise the 8034 * successful stats retrievals would get lost. 8035 */ 8036 netdev_hw_stats64_add(stats, &report_delta.stats); 8037 8038 if (p_stats) 8039 *p_stats = *stats; 8040 *p_used = report_delta.used; 8041 8042 return notifier_to_errno(rc); 8043 } 8044 8045 int netdev_offload_xstats_get(struct net_device *dev, 8046 enum netdev_offload_xstats_type type, 8047 struct rtnl_hw_stats64 *p_stats, bool *p_used, 8048 struct netlink_ext_ack *extack) 8049 { 8050 ASSERT_RTNL(); 8051 8052 if (p_stats) 8053 return netdev_offload_xstats_get_stats(dev, type, p_stats, 8054 p_used, extack); 8055 else 8056 return netdev_offload_xstats_get_used(dev, type, p_used, 8057 extack); 8058 } 8059 EXPORT_SYMBOL(netdev_offload_xstats_get); 8060 8061 void 8062 netdev_offload_xstats_report_delta(struct netdev_notifier_offload_xstats_rd *report_delta, 8063 const struct rtnl_hw_stats64 *stats) 8064 { 8065 report_delta->used = true; 8066 netdev_hw_stats64_add(&report_delta->stats, stats); 8067 } 8068 EXPORT_SYMBOL(netdev_offload_xstats_report_delta); 8069 8070 void 8071 netdev_offload_xstats_report_used(struct netdev_notifier_offload_xstats_ru *report_used) 8072 { 8073 report_used->used = true; 8074 } 8075 EXPORT_SYMBOL(netdev_offload_xstats_report_used); 8076 8077 void netdev_offload_xstats_push_delta(struct net_device *dev, 8078 enum netdev_offload_xstats_type type, 8079 const struct rtnl_hw_stats64 *p_stats) 8080 { 8081 struct rtnl_hw_stats64 *stats; 8082 8083 ASSERT_RTNL(); 8084 8085 stats = netdev_offload_xstats_get_ptr(dev, type); 8086 if (WARN_ON(!stats)) 8087 return; 8088 8089 netdev_hw_stats64_add(stats, p_stats); 8090 } 8091 EXPORT_SYMBOL(netdev_offload_xstats_push_delta); 8092 8093 /** 8094 * netdev_get_xmit_slave - Get the xmit slave of master device 8095 * @dev: device 8096 * @skb: The packet 8097 * @all_slaves: assume all the slaves are active 8098 * 8099 * The reference counters are not incremented so the caller must be 8100 * careful with locks. The caller must hold RCU lock. 8101 * %NULL is returned if no slave is found. 8102 */ 8103 8104 struct net_device *netdev_get_xmit_slave(struct net_device *dev, 8105 struct sk_buff *skb, 8106 bool all_slaves) 8107 { 8108 const struct net_device_ops *ops = dev->netdev_ops; 8109 8110 if (!ops->ndo_get_xmit_slave) 8111 return NULL; 8112 return ops->ndo_get_xmit_slave(dev, skb, all_slaves); 8113 } 8114 EXPORT_SYMBOL(netdev_get_xmit_slave); 8115 8116 static struct net_device *netdev_sk_get_lower_dev(struct net_device *dev, 8117 struct sock *sk) 8118 { 8119 const struct net_device_ops *ops = dev->netdev_ops; 8120 8121 if (!ops->ndo_sk_get_lower_dev) 8122 return NULL; 8123 return ops->ndo_sk_get_lower_dev(dev, sk); 8124 } 8125 8126 /** 8127 * netdev_sk_get_lowest_dev - Get the lowest device in chain given device and socket 8128 * @dev: device 8129 * @sk: the socket 8130 * 8131 * %NULL is returned if no lower device is found. 8132 */ 8133 8134 struct net_device *netdev_sk_get_lowest_dev(struct net_device *dev, 8135 struct sock *sk) 8136 { 8137 struct net_device *lower; 8138 8139 lower = netdev_sk_get_lower_dev(dev, sk); 8140 while (lower) { 8141 dev = lower; 8142 lower = netdev_sk_get_lower_dev(dev, sk); 8143 } 8144 8145 return dev; 8146 } 8147 EXPORT_SYMBOL(netdev_sk_get_lowest_dev); 8148 8149 static void netdev_adjacent_add_links(struct net_device *dev) 8150 { 8151 struct netdev_adjacent *iter; 8152 8153 struct net *net = dev_net(dev); 8154 8155 list_for_each_entry(iter, &dev->adj_list.upper, list) { 8156 if (!net_eq(net, dev_net(iter->dev))) 8157 continue; 8158 netdev_adjacent_sysfs_add(iter->dev, dev, 8159 &iter->dev->adj_list.lower); 8160 netdev_adjacent_sysfs_add(dev, iter->dev, 8161 &dev->adj_list.upper); 8162 } 8163 8164 list_for_each_entry(iter, &dev->adj_list.lower, list) { 8165 if (!net_eq(net, dev_net(iter->dev))) 8166 continue; 8167 netdev_adjacent_sysfs_add(iter->dev, dev, 8168 &iter->dev->adj_list.upper); 8169 netdev_adjacent_sysfs_add(dev, iter->dev, 8170 &dev->adj_list.lower); 8171 } 8172 } 8173 8174 static void netdev_adjacent_del_links(struct net_device *dev) 8175 { 8176 struct netdev_adjacent *iter; 8177 8178 struct net *net = dev_net(dev); 8179 8180 list_for_each_entry(iter, &dev->adj_list.upper, list) { 8181 if (!net_eq(net, dev_net(iter->dev))) 8182 continue; 8183 netdev_adjacent_sysfs_del(iter->dev, dev->name, 8184 &iter->dev->adj_list.lower); 8185 netdev_adjacent_sysfs_del(dev, iter->dev->name, 8186 &dev->adj_list.upper); 8187 } 8188 8189 list_for_each_entry(iter, &dev->adj_list.lower, list) { 8190 if (!net_eq(net, dev_net(iter->dev))) 8191 continue; 8192 netdev_adjacent_sysfs_del(iter->dev, dev->name, 8193 &iter->dev->adj_list.upper); 8194 netdev_adjacent_sysfs_del(dev, iter->dev->name, 8195 &dev->adj_list.lower); 8196 } 8197 } 8198 8199 void netdev_adjacent_rename_links(struct net_device *dev, char *oldname) 8200 { 8201 struct netdev_adjacent *iter; 8202 8203 struct net *net = dev_net(dev); 8204 8205 list_for_each_entry(iter, &dev->adj_list.upper, list) { 8206 if (!net_eq(net, dev_net(iter->dev))) 8207 continue; 8208 netdev_adjacent_sysfs_del(iter->dev, oldname, 8209 &iter->dev->adj_list.lower); 8210 netdev_adjacent_sysfs_add(iter->dev, dev, 8211 &iter->dev->adj_list.lower); 8212 } 8213 8214 list_for_each_entry(iter, &dev->adj_list.lower, list) { 8215 if (!net_eq(net, dev_net(iter->dev))) 8216 continue; 8217 netdev_adjacent_sysfs_del(iter->dev, oldname, 8218 &iter->dev->adj_list.upper); 8219 netdev_adjacent_sysfs_add(iter->dev, dev, 8220 &iter->dev->adj_list.upper); 8221 } 8222 } 8223 8224 void *netdev_lower_dev_get_private(struct net_device *dev, 8225 struct net_device *lower_dev) 8226 { 8227 struct netdev_adjacent *lower; 8228 8229 if (!lower_dev) 8230 return NULL; 8231 lower = __netdev_find_adj(lower_dev, &dev->adj_list.lower); 8232 if (!lower) 8233 return NULL; 8234 8235 return lower->private; 8236 } 8237 EXPORT_SYMBOL(netdev_lower_dev_get_private); 8238 8239 8240 /** 8241 * netdev_lower_state_changed - Dispatch event about lower device state change 8242 * @lower_dev: device 8243 * @lower_state_info: state to dispatch 8244 * 8245 * Send NETDEV_CHANGELOWERSTATE to netdev notifiers with info. 8246 * The caller must hold the RTNL lock. 8247 */ 8248 void netdev_lower_state_changed(struct net_device *lower_dev, 8249 void *lower_state_info) 8250 { 8251 struct netdev_notifier_changelowerstate_info changelowerstate_info = { 8252 .info.dev = lower_dev, 8253 }; 8254 8255 ASSERT_RTNL(); 8256 changelowerstate_info.lower_state_info = lower_state_info; 8257 call_netdevice_notifiers_info(NETDEV_CHANGELOWERSTATE, 8258 &changelowerstate_info.info); 8259 } 8260 EXPORT_SYMBOL(netdev_lower_state_changed); 8261 8262 static void dev_change_rx_flags(struct net_device *dev, int flags) 8263 { 8264 const struct net_device_ops *ops = dev->netdev_ops; 8265 8266 if (ops->ndo_change_rx_flags) 8267 ops->ndo_change_rx_flags(dev, flags); 8268 } 8269 8270 static int __dev_set_promiscuity(struct net_device *dev, int inc, bool notify) 8271 { 8272 unsigned int old_flags = dev->flags; 8273 kuid_t uid; 8274 kgid_t gid; 8275 8276 ASSERT_RTNL(); 8277 8278 dev->flags |= IFF_PROMISC; 8279 dev->promiscuity += inc; 8280 if (dev->promiscuity == 0) { 8281 /* 8282 * Avoid overflow. 8283 * If inc causes overflow, untouch promisc and return error. 8284 */ 8285 if (inc < 0) 8286 dev->flags &= ~IFF_PROMISC; 8287 else { 8288 dev->promiscuity -= inc; 8289 netdev_warn(dev, "promiscuity touches roof, set promiscuity failed. promiscuity feature of device might be broken.\n"); 8290 return -EOVERFLOW; 8291 } 8292 } 8293 if (dev->flags != old_flags) { 8294 netdev_info(dev, "%s promiscuous mode\n", 8295 dev->flags & IFF_PROMISC ? "entered" : "left"); 8296 if (audit_enabled) { 8297 current_uid_gid(&uid, &gid); 8298 audit_log(audit_context(), GFP_ATOMIC, 8299 AUDIT_ANOM_PROMISCUOUS, 8300 "dev=%s prom=%d old_prom=%d auid=%u uid=%u gid=%u ses=%u", 8301 dev->name, (dev->flags & IFF_PROMISC), 8302 (old_flags & IFF_PROMISC), 8303 from_kuid(&init_user_ns, audit_get_loginuid(current)), 8304 from_kuid(&init_user_ns, uid), 8305 from_kgid(&init_user_ns, gid), 8306 audit_get_sessionid(current)); 8307 } 8308 8309 dev_change_rx_flags(dev, IFF_PROMISC); 8310 } 8311 if (notify) 8312 __dev_notify_flags(dev, old_flags, IFF_PROMISC, 0, NULL); 8313 return 0; 8314 } 8315 8316 /** 8317 * dev_set_promiscuity - update promiscuity count on a device 8318 * @dev: device 8319 * @inc: modifier 8320 * 8321 * Add or remove promiscuity from a device. While the count in the device 8322 * remains above zero the interface remains promiscuous. Once it hits zero 8323 * the device reverts back to normal filtering operation. A negative inc 8324 * value is used to drop promiscuity on the device. 8325 * Return 0 if successful or a negative errno code on error. 8326 */ 8327 int dev_set_promiscuity(struct net_device *dev, int inc) 8328 { 8329 unsigned int old_flags = dev->flags; 8330 int err; 8331 8332 err = __dev_set_promiscuity(dev, inc, true); 8333 if (err < 0) 8334 return err; 8335 if (dev->flags != old_flags) 8336 dev_set_rx_mode(dev); 8337 return err; 8338 } 8339 EXPORT_SYMBOL(dev_set_promiscuity); 8340 8341 static int __dev_set_allmulti(struct net_device *dev, int inc, bool notify) 8342 { 8343 unsigned int old_flags = dev->flags, old_gflags = dev->gflags; 8344 8345 ASSERT_RTNL(); 8346 8347 dev->flags |= IFF_ALLMULTI; 8348 dev->allmulti += inc; 8349 if (dev->allmulti == 0) { 8350 /* 8351 * Avoid overflow. 8352 * If inc causes overflow, untouch allmulti and return error. 8353 */ 8354 if (inc < 0) 8355 dev->flags &= ~IFF_ALLMULTI; 8356 else { 8357 dev->allmulti -= inc; 8358 netdev_warn(dev, "allmulti touches roof, set allmulti failed. allmulti feature of device might be broken.\n"); 8359 return -EOVERFLOW; 8360 } 8361 } 8362 if (dev->flags ^ old_flags) { 8363 netdev_info(dev, "%s allmulticast mode\n", 8364 dev->flags & IFF_ALLMULTI ? "entered" : "left"); 8365 dev_change_rx_flags(dev, IFF_ALLMULTI); 8366 dev_set_rx_mode(dev); 8367 if (notify) 8368 __dev_notify_flags(dev, old_flags, 8369 dev->gflags ^ old_gflags, 0, NULL); 8370 } 8371 return 0; 8372 } 8373 8374 /** 8375 * dev_set_allmulti - update allmulti count on a device 8376 * @dev: device 8377 * @inc: modifier 8378 * 8379 * Add or remove reception of all multicast frames to a device. While the 8380 * count in the device remains above zero the interface remains listening 8381 * to all interfaces. Once it hits zero the device reverts back to normal 8382 * filtering operation. A negative @inc value is used to drop the counter 8383 * when releasing a resource needing all multicasts. 8384 * Return 0 if successful or a negative errno code on error. 8385 */ 8386 8387 int dev_set_allmulti(struct net_device *dev, int inc) 8388 { 8389 return __dev_set_allmulti(dev, inc, true); 8390 } 8391 EXPORT_SYMBOL(dev_set_allmulti); 8392 8393 /* 8394 * Upload unicast and multicast address lists to device and 8395 * configure RX filtering. When the device doesn't support unicast 8396 * filtering it is put in promiscuous mode while unicast addresses 8397 * are present. 8398 */ 8399 void __dev_set_rx_mode(struct net_device *dev) 8400 { 8401 const struct net_device_ops *ops = dev->netdev_ops; 8402 8403 /* dev_open will call this function so the list will stay sane. */ 8404 if (!(dev->flags&IFF_UP)) 8405 return; 8406 8407 if (!netif_device_present(dev)) 8408 return; 8409 8410 if (!(dev->priv_flags & IFF_UNICAST_FLT)) { 8411 /* Unicast addresses changes may only happen under the rtnl, 8412 * therefore calling __dev_set_promiscuity here is safe. 8413 */ 8414 if (!netdev_uc_empty(dev) && !dev->uc_promisc) { 8415 __dev_set_promiscuity(dev, 1, false); 8416 dev->uc_promisc = true; 8417 } else if (netdev_uc_empty(dev) && dev->uc_promisc) { 8418 __dev_set_promiscuity(dev, -1, false); 8419 dev->uc_promisc = false; 8420 } 8421 } 8422 8423 if (ops->ndo_set_rx_mode) 8424 ops->ndo_set_rx_mode(dev); 8425 } 8426 8427 void dev_set_rx_mode(struct net_device *dev) 8428 { 8429 netif_addr_lock_bh(dev); 8430 __dev_set_rx_mode(dev); 8431 netif_addr_unlock_bh(dev); 8432 } 8433 8434 /** 8435 * dev_get_flags - get flags reported to userspace 8436 * @dev: device 8437 * 8438 * Get the combination of flag bits exported through APIs to userspace. 8439 */ 8440 unsigned int dev_get_flags(const struct net_device *dev) 8441 { 8442 unsigned int flags; 8443 8444 flags = (dev->flags & ~(IFF_PROMISC | 8445 IFF_ALLMULTI | 8446 IFF_RUNNING | 8447 IFF_LOWER_UP | 8448 IFF_DORMANT)) | 8449 (dev->gflags & (IFF_PROMISC | 8450 IFF_ALLMULTI)); 8451 8452 if (netif_running(dev)) { 8453 if (netif_oper_up(dev)) 8454 flags |= IFF_RUNNING; 8455 if (netif_carrier_ok(dev)) 8456 flags |= IFF_LOWER_UP; 8457 if (netif_dormant(dev)) 8458 flags |= IFF_DORMANT; 8459 } 8460 8461 return flags; 8462 } 8463 EXPORT_SYMBOL(dev_get_flags); 8464 8465 int __dev_change_flags(struct net_device *dev, unsigned int flags, 8466 struct netlink_ext_ack *extack) 8467 { 8468 unsigned int old_flags = dev->flags; 8469 int ret; 8470 8471 ASSERT_RTNL(); 8472 8473 /* 8474 * Set the flags on our device. 8475 */ 8476 8477 dev->flags = (flags & (IFF_DEBUG | IFF_NOTRAILERS | IFF_NOARP | 8478 IFF_DYNAMIC | IFF_MULTICAST | IFF_PORTSEL | 8479 IFF_AUTOMEDIA)) | 8480 (dev->flags & (IFF_UP | IFF_VOLATILE | IFF_PROMISC | 8481 IFF_ALLMULTI)); 8482 8483 /* 8484 * Load in the correct multicast list now the flags have changed. 8485 */ 8486 8487 if ((old_flags ^ flags) & IFF_MULTICAST) 8488 dev_change_rx_flags(dev, IFF_MULTICAST); 8489 8490 dev_set_rx_mode(dev); 8491 8492 /* 8493 * Have we downed the interface. We handle IFF_UP ourselves 8494 * according to user attempts to set it, rather than blindly 8495 * setting it. 8496 */ 8497 8498 ret = 0; 8499 if ((old_flags ^ flags) & IFF_UP) { 8500 if (old_flags & IFF_UP) 8501 __dev_close(dev); 8502 else 8503 ret = __dev_open(dev, extack); 8504 } 8505 8506 if ((flags ^ dev->gflags) & IFF_PROMISC) { 8507 int inc = (flags & IFF_PROMISC) ? 1 : -1; 8508 unsigned int old_flags = dev->flags; 8509 8510 dev->gflags ^= IFF_PROMISC; 8511 8512 if (__dev_set_promiscuity(dev, inc, false) >= 0) 8513 if (dev->flags != old_flags) 8514 dev_set_rx_mode(dev); 8515 } 8516 8517 /* NOTE: order of synchronization of IFF_PROMISC and IFF_ALLMULTI 8518 * is important. Some (broken) drivers set IFF_PROMISC, when 8519 * IFF_ALLMULTI is requested not asking us and not reporting. 8520 */ 8521 if ((flags ^ dev->gflags) & IFF_ALLMULTI) { 8522 int inc = (flags & IFF_ALLMULTI) ? 1 : -1; 8523 8524 dev->gflags ^= IFF_ALLMULTI; 8525 __dev_set_allmulti(dev, inc, false); 8526 } 8527 8528 return ret; 8529 } 8530 8531 void __dev_notify_flags(struct net_device *dev, unsigned int old_flags, 8532 unsigned int gchanges, u32 portid, 8533 const struct nlmsghdr *nlh) 8534 { 8535 unsigned int changes = dev->flags ^ old_flags; 8536 8537 if (gchanges) 8538 rtmsg_ifinfo(RTM_NEWLINK, dev, gchanges, GFP_ATOMIC, portid, nlh); 8539 8540 if (changes & IFF_UP) { 8541 if (dev->flags & IFF_UP) 8542 call_netdevice_notifiers(NETDEV_UP, dev); 8543 else 8544 call_netdevice_notifiers(NETDEV_DOWN, dev); 8545 } 8546 8547 if (dev->flags & IFF_UP && 8548 (changes & ~(IFF_UP | IFF_PROMISC | IFF_ALLMULTI | IFF_VOLATILE))) { 8549 struct netdev_notifier_change_info change_info = { 8550 .info = { 8551 .dev = dev, 8552 }, 8553 .flags_changed = changes, 8554 }; 8555 8556 call_netdevice_notifiers_info(NETDEV_CHANGE, &change_info.info); 8557 } 8558 } 8559 8560 /** 8561 * dev_change_flags - change device settings 8562 * @dev: device 8563 * @flags: device state flags 8564 * @extack: netlink extended ack 8565 * 8566 * Change settings on device based state flags. The flags are 8567 * in the userspace exported format. 8568 */ 8569 int dev_change_flags(struct net_device *dev, unsigned int flags, 8570 struct netlink_ext_ack *extack) 8571 { 8572 int ret; 8573 unsigned int changes, old_flags = dev->flags, old_gflags = dev->gflags; 8574 8575 ret = __dev_change_flags(dev, flags, extack); 8576 if (ret < 0) 8577 return ret; 8578 8579 changes = (old_flags ^ dev->flags) | (old_gflags ^ dev->gflags); 8580 __dev_notify_flags(dev, old_flags, changes, 0, NULL); 8581 return ret; 8582 } 8583 EXPORT_SYMBOL(dev_change_flags); 8584 8585 int __dev_set_mtu(struct net_device *dev, int new_mtu) 8586 { 8587 const struct net_device_ops *ops = dev->netdev_ops; 8588 8589 if (ops->ndo_change_mtu) 8590 return ops->ndo_change_mtu(dev, new_mtu); 8591 8592 /* Pairs with all the lockless reads of dev->mtu in the stack */ 8593 WRITE_ONCE(dev->mtu, new_mtu); 8594 return 0; 8595 } 8596 EXPORT_SYMBOL(__dev_set_mtu); 8597 8598 int dev_validate_mtu(struct net_device *dev, int new_mtu, 8599 struct netlink_ext_ack *extack) 8600 { 8601 /* MTU must be positive, and in range */ 8602 if (new_mtu < 0 || new_mtu < dev->min_mtu) { 8603 NL_SET_ERR_MSG(extack, "mtu less than device minimum"); 8604 return -EINVAL; 8605 } 8606 8607 if (dev->max_mtu > 0 && new_mtu > dev->max_mtu) { 8608 NL_SET_ERR_MSG(extack, "mtu greater than device maximum"); 8609 return -EINVAL; 8610 } 8611 return 0; 8612 } 8613 8614 /** 8615 * dev_set_mtu_ext - Change maximum transfer unit 8616 * @dev: device 8617 * @new_mtu: new transfer unit 8618 * @extack: netlink extended ack 8619 * 8620 * Change the maximum transfer size of the network device. 8621 */ 8622 int dev_set_mtu_ext(struct net_device *dev, int new_mtu, 8623 struct netlink_ext_ack *extack) 8624 { 8625 int err, orig_mtu; 8626 8627 if (new_mtu == dev->mtu) 8628 return 0; 8629 8630 err = dev_validate_mtu(dev, new_mtu, extack); 8631 if (err) 8632 return err; 8633 8634 if (!netif_device_present(dev)) 8635 return -ENODEV; 8636 8637 err = call_netdevice_notifiers(NETDEV_PRECHANGEMTU, dev); 8638 err = notifier_to_errno(err); 8639 if (err) 8640 return err; 8641 8642 orig_mtu = dev->mtu; 8643 err = __dev_set_mtu(dev, new_mtu); 8644 8645 if (!err) { 8646 err = call_netdevice_notifiers_mtu(NETDEV_CHANGEMTU, dev, 8647 orig_mtu); 8648 err = notifier_to_errno(err); 8649 if (err) { 8650 /* setting mtu back and notifying everyone again, 8651 * so that they have a chance to revert changes. 8652 */ 8653 __dev_set_mtu(dev, orig_mtu); 8654 call_netdevice_notifiers_mtu(NETDEV_CHANGEMTU, dev, 8655 new_mtu); 8656 } 8657 } 8658 return err; 8659 } 8660 8661 int dev_set_mtu(struct net_device *dev, int new_mtu) 8662 { 8663 struct netlink_ext_ack extack; 8664 int err; 8665 8666 memset(&extack, 0, sizeof(extack)); 8667 err = dev_set_mtu_ext(dev, new_mtu, &extack); 8668 if (err && extack._msg) 8669 net_err_ratelimited("%s: %s\n", dev->name, extack._msg); 8670 return err; 8671 } 8672 EXPORT_SYMBOL(dev_set_mtu); 8673 8674 /** 8675 * dev_change_tx_queue_len - Change TX queue length of a netdevice 8676 * @dev: device 8677 * @new_len: new tx queue length 8678 */ 8679 int dev_change_tx_queue_len(struct net_device *dev, unsigned long new_len) 8680 { 8681 unsigned int orig_len = dev->tx_queue_len; 8682 int res; 8683 8684 if (new_len != (unsigned int)new_len) 8685 return -ERANGE; 8686 8687 if (new_len != orig_len) { 8688 dev->tx_queue_len = new_len; 8689 res = call_netdevice_notifiers(NETDEV_CHANGE_TX_QUEUE_LEN, dev); 8690 res = notifier_to_errno(res); 8691 if (res) 8692 goto err_rollback; 8693 res = dev_qdisc_change_tx_queue_len(dev); 8694 if (res) 8695 goto err_rollback; 8696 } 8697 8698 return 0; 8699 8700 err_rollback: 8701 netdev_err(dev, "refused to change device tx_queue_len\n"); 8702 dev->tx_queue_len = orig_len; 8703 return res; 8704 } 8705 8706 /** 8707 * dev_set_group - Change group this device belongs to 8708 * @dev: device 8709 * @new_group: group this device should belong to 8710 */ 8711 void dev_set_group(struct net_device *dev, int new_group) 8712 { 8713 dev->group = new_group; 8714 } 8715 8716 /** 8717 * dev_pre_changeaddr_notify - Call NETDEV_PRE_CHANGEADDR. 8718 * @dev: device 8719 * @addr: new address 8720 * @extack: netlink extended ack 8721 */ 8722 int dev_pre_changeaddr_notify(struct net_device *dev, const char *addr, 8723 struct netlink_ext_ack *extack) 8724 { 8725 struct netdev_notifier_pre_changeaddr_info info = { 8726 .info.dev = dev, 8727 .info.extack = extack, 8728 .dev_addr = addr, 8729 }; 8730 int rc; 8731 8732 rc = call_netdevice_notifiers_info(NETDEV_PRE_CHANGEADDR, &info.info); 8733 return notifier_to_errno(rc); 8734 } 8735 EXPORT_SYMBOL(dev_pre_changeaddr_notify); 8736 8737 /** 8738 * dev_set_mac_address - Change Media Access Control Address 8739 * @dev: device 8740 * @sa: new address 8741 * @extack: netlink extended ack 8742 * 8743 * Change the hardware (MAC) address of the device 8744 */ 8745 int dev_set_mac_address(struct net_device *dev, struct sockaddr *sa, 8746 struct netlink_ext_ack *extack) 8747 { 8748 const struct net_device_ops *ops = dev->netdev_ops; 8749 int err; 8750 8751 if (!ops->ndo_set_mac_address) 8752 return -EOPNOTSUPP; 8753 if (sa->sa_family != dev->type) 8754 return -EINVAL; 8755 if (!netif_device_present(dev)) 8756 return -ENODEV; 8757 err = dev_pre_changeaddr_notify(dev, sa->sa_data, extack); 8758 if (err) 8759 return err; 8760 err = ops->ndo_set_mac_address(dev, sa); 8761 if (err) 8762 return err; 8763 dev->addr_assign_type = NET_ADDR_SET; 8764 call_netdevice_notifiers(NETDEV_CHANGEADDR, dev); 8765 add_device_randomness(dev->dev_addr, dev->addr_len); 8766 return 0; 8767 } 8768 EXPORT_SYMBOL(dev_set_mac_address); 8769 8770 static DECLARE_RWSEM(dev_addr_sem); 8771 8772 int dev_set_mac_address_user(struct net_device *dev, struct sockaddr *sa, 8773 struct netlink_ext_ack *extack) 8774 { 8775 int ret; 8776 8777 down_write(&dev_addr_sem); 8778 ret = dev_set_mac_address(dev, sa, extack); 8779 up_write(&dev_addr_sem); 8780 return ret; 8781 } 8782 EXPORT_SYMBOL(dev_set_mac_address_user); 8783 8784 int dev_get_mac_address(struct sockaddr *sa, struct net *net, char *dev_name) 8785 { 8786 size_t size = sizeof(sa->sa_data_min); 8787 struct net_device *dev; 8788 int ret = 0; 8789 8790 down_read(&dev_addr_sem); 8791 rcu_read_lock(); 8792 8793 dev = dev_get_by_name_rcu(net, dev_name); 8794 if (!dev) { 8795 ret = -ENODEV; 8796 goto unlock; 8797 } 8798 if (!dev->addr_len) 8799 memset(sa->sa_data, 0, size); 8800 else 8801 memcpy(sa->sa_data, dev->dev_addr, 8802 min_t(size_t, size, dev->addr_len)); 8803 sa->sa_family = dev->type; 8804 8805 unlock: 8806 rcu_read_unlock(); 8807 up_read(&dev_addr_sem); 8808 return ret; 8809 } 8810 EXPORT_SYMBOL(dev_get_mac_address); 8811 8812 /** 8813 * dev_change_carrier - Change device carrier 8814 * @dev: device 8815 * @new_carrier: new value 8816 * 8817 * Change device carrier 8818 */ 8819 int dev_change_carrier(struct net_device *dev, bool new_carrier) 8820 { 8821 const struct net_device_ops *ops = dev->netdev_ops; 8822 8823 if (!ops->ndo_change_carrier) 8824 return -EOPNOTSUPP; 8825 if (!netif_device_present(dev)) 8826 return -ENODEV; 8827 return ops->ndo_change_carrier(dev, new_carrier); 8828 } 8829 8830 /** 8831 * dev_get_phys_port_id - Get device physical port ID 8832 * @dev: device 8833 * @ppid: port ID 8834 * 8835 * Get device physical port ID 8836 */ 8837 int dev_get_phys_port_id(struct net_device *dev, 8838 struct netdev_phys_item_id *ppid) 8839 { 8840 const struct net_device_ops *ops = dev->netdev_ops; 8841 8842 if (!ops->ndo_get_phys_port_id) 8843 return -EOPNOTSUPP; 8844 return ops->ndo_get_phys_port_id(dev, ppid); 8845 } 8846 8847 /** 8848 * dev_get_phys_port_name - Get device physical port name 8849 * @dev: device 8850 * @name: port name 8851 * @len: limit of bytes to copy to name 8852 * 8853 * Get device physical port name 8854 */ 8855 int dev_get_phys_port_name(struct net_device *dev, 8856 char *name, size_t len) 8857 { 8858 const struct net_device_ops *ops = dev->netdev_ops; 8859 int err; 8860 8861 if (ops->ndo_get_phys_port_name) { 8862 err = ops->ndo_get_phys_port_name(dev, name, len); 8863 if (err != -EOPNOTSUPP) 8864 return err; 8865 } 8866 return devlink_compat_phys_port_name_get(dev, name, len); 8867 } 8868 8869 /** 8870 * dev_get_port_parent_id - Get the device's port parent identifier 8871 * @dev: network device 8872 * @ppid: pointer to a storage for the port's parent identifier 8873 * @recurse: allow/disallow recursion to lower devices 8874 * 8875 * Get the devices's port parent identifier 8876 */ 8877 int dev_get_port_parent_id(struct net_device *dev, 8878 struct netdev_phys_item_id *ppid, 8879 bool recurse) 8880 { 8881 const struct net_device_ops *ops = dev->netdev_ops; 8882 struct netdev_phys_item_id first = { }; 8883 struct net_device *lower_dev; 8884 struct list_head *iter; 8885 int err; 8886 8887 if (ops->ndo_get_port_parent_id) { 8888 err = ops->ndo_get_port_parent_id(dev, ppid); 8889 if (err != -EOPNOTSUPP) 8890 return err; 8891 } 8892 8893 err = devlink_compat_switch_id_get(dev, ppid); 8894 if (!recurse || err != -EOPNOTSUPP) 8895 return err; 8896 8897 netdev_for_each_lower_dev(dev, lower_dev, iter) { 8898 err = dev_get_port_parent_id(lower_dev, ppid, true); 8899 if (err) 8900 break; 8901 if (!first.id_len) 8902 first = *ppid; 8903 else if (memcmp(&first, ppid, sizeof(*ppid))) 8904 return -EOPNOTSUPP; 8905 } 8906 8907 return err; 8908 } 8909 EXPORT_SYMBOL(dev_get_port_parent_id); 8910 8911 /** 8912 * netdev_port_same_parent_id - Indicate if two network devices have 8913 * the same port parent identifier 8914 * @a: first network device 8915 * @b: second network device 8916 */ 8917 bool netdev_port_same_parent_id(struct net_device *a, struct net_device *b) 8918 { 8919 struct netdev_phys_item_id a_id = { }; 8920 struct netdev_phys_item_id b_id = { }; 8921 8922 if (dev_get_port_parent_id(a, &a_id, true) || 8923 dev_get_port_parent_id(b, &b_id, true)) 8924 return false; 8925 8926 return netdev_phys_item_id_same(&a_id, &b_id); 8927 } 8928 EXPORT_SYMBOL(netdev_port_same_parent_id); 8929 8930 /** 8931 * dev_change_proto_down - set carrier according to proto_down. 8932 * 8933 * @dev: device 8934 * @proto_down: new value 8935 */ 8936 int dev_change_proto_down(struct net_device *dev, bool proto_down) 8937 { 8938 if (!(dev->priv_flags & IFF_CHANGE_PROTO_DOWN)) 8939 return -EOPNOTSUPP; 8940 if (!netif_device_present(dev)) 8941 return -ENODEV; 8942 if (proto_down) 8943 netif_carrier_off(dev); 8944 else 8945 netif_carrier_on(dev); 8946 dev->proto_down = proto_down; 8947 return 0; 8948 } 8949 8950 /** 8951 * dev_change_proto_down_reason - proto down reason 8952 * 8953 * @dev: device 8954 * @mask: proto down mask 8955 * @value: proto down value 8956 */ 8957 void dev_change_proto_down_reason(struct net_device *dev, unsigned long mask, 8958 u32 value) 8959 { 8960 int b; 8961 8962 if (!mask) { 8963 dev->proto_down_reason = value; 8964 } else { 8965 for_each_set_bit(b, &mask, 32) { 8966 if (value & (1 << b)) 8967 dev->proto_down_reason |= BIT(b); 8968 else 8969 dev->proto_down_reason &= ~BIT(b); 8970 } 8971 } 8972 } 8973 8974 struct bpf_xdp_link { 8975 struct bpf_link link; 8976 struct net_device *dev; /* protected by rtnl_lock, no refcnt held */ 8977 int flags; 8978 }; 8979 8980 static enum bpf_xdp_mode dev_xdp_mode(struct net_device *dev, u32 flags) 8981 { 8982 if (flags & XDP_FLAGS_HW_MODE) 8983 return XDP_MODE_HW; 8984 if (flags & XDP_FLAGS_DRV_MODE) 8985 return XDP_MODE_DRV; 8986 if (flags & XDP_FLAGS_SKB_MODE) 8987 return XDP_MODE_SKB; 8988 return dev->netdev_ops->ndo_bpf ? XDP_MODE_DRV : XDP_MODE_SKB; 8989 } 8990 8991 static bpf_op_t dev_xdp_bpf_op(struct net_device *dev, enum bpf_xdp_mode mode) 8992 { 8993 switch (mode) { 8994 case XDP_MODE_SKB: 8995 return generic_xdp_install; 8996 case XDP_MODE_DRV: 8997 case XDP_MODE_HW: 8998 return dev->netdev_ops->ndo_bpf; 8999 default: 9000 return NULL; 9001 } 9002 } 9003 9004 static struct bpf_xdp_link *dev_xdp_link(struct net_device *dev, 9005 enum bpf_xdp_mode mode) 9006 { 9007 return dev->xdp_state[mode].link; 9008 } 9009 9010 static struct bpf_prog *dev_xdp_prog(struct net_device *dev, 9011 enum bpf_xdp_mode mode) 9012 { 9013 struct bpf_xdp_link *link = dev_xdp_link(dev, mode); 9014 9015 if (link) 9016 return link->link.prog; 9017 return dev->xdp_state[mode].prog; 9018 } 9019 9020 u8 dev_xdp_prog_count(struct net_device *dev) 9021 { 9022 u8 count = 0; 9023 int i; 9024 9025 for (i = 0; i < __MAX_XDP_MODE; i++) 9026 if (dev->xdp_state[i].prog || dev->xdp_state[i].link) 9027 count++; 9028 return count; 9029 } 9030 EXPORT_SYMBOL_GPL(dev_xdp_prog_count); 9031 9032 u32 dev_xdp_prog_id(struct net_device *dev, enum bpf_xdp_mode mode) 9033 { 9034 struct bpf_prog *prog = dev_xdp_prog(dev, mode); 9035 9036 return prog ? prog->aux->id : 0; 9037 } 9038 9039 static void dev_xdp_set_link(struct net_device *dev, enum bpf_xdp_mode mode, 9040 struct bpf_xdp_link *link) 9041 { 9042 dev->xdp_state[mode].link = link; 9043 dev->xdp_state[mode].prog = NULL; 9044 } 9045 9046 static void dev_xdp_set_prog(struct net_device *dev, enum bpf_xdp_mode mode, 9047 struct bpf_prog *prog) 9048 { 9049 dev->xdp_state[mode].link = NULL; 9050 dev->xdp_state[mode].prog = prog; 9051 } 9052 9053 static int dev_xdp_install(struct net_device *dev, enum bpf_xdp_mode mode, 9054 bpf_op_t bpf_op, struct netlink_ext_ack *extack, 9055 u32 flags, struct bpf_prog *prog) 9056 { 9057 struct netdev_bpf xdp; 9058 int err; 9059 9060 memset(&xdp, 0, sizeof(xdp)); 9061 xdp.command = mode == XDP_MODE_HW ? XDP_SETUP_PROG_HW : XDP_SETUP_PROG; 9062 xdp.extack = extack; 9063 xdp.flags = flags; 9064 xdp.prog = prog; 9065 9066 /* Drivers assume refcnt is already incremented (i.e, prog pointer is 9067 * "moved" into driver), so they don't increment it on their own, but 9068 * they do decrement refcnt when program is detached or replaced. 9069 * Given net_device also owns link/prog, we need to bump refcnt here 9070 * to prevent drivers from underflowing it. 9071 */ 9072 if (prog) 9073 bpf_prog_inc(prog); 9074 err = bpf_op(dev, &xdp); 9075 if (err) { 9076 if (prog) 9077 bpf_prog_put(prog); 9078 return err; 9079 } 9080 9081 if (mode != XDP_MODE_HW) 9082 bpf_prog_change_xdp(dev_xdp_prog(dev, mode), prog); 9083 9084 return 0; 9085 } 9086 9087 static void dev_xdp_uninstall(struct net_device *dev) 9088 { 9089 struct bpf_xdp_link *link; 9090 struct bpf_prog *prog; 9091 enum bpf_xdp_mode mode; 9092 bpf_op_t bpf_op; 9093 9094 ASSERT_RTNL(); 9095 9096 for (mode = XDP_MODE_SKB; mode < __MAX_XDP_MODE; mode++) { 9097 prog = dev_xdp_prog(dev, mode); 9098 if (!prog) 9099 continue; 9100 9101 bpf_op = dev_xdp_bpf_op(dev, mode); 9102 if (!bpf_op) 9103 continue; 9104 9105 WARN_ON(dev_xdp_install(dev, mode, bpf_op, NULL, 0, NULL)); 9106 9107 /* auto-detach link from net device */ 9108 link = dev_xdp_link(dev, mode); 9109 if (link) 9110 link->dev = NULL; 9111 else 9112 bpf_prog_put(prog); 9113 9114 dev_xdp_set_link(dev, mode, NULL); 9115 } 9116 } 9117 9118 static int dev_xdp_attach(struct net_device *dev, struct netlink_ext_ack *extack, 9119 struct bpf_xdp_link *link, struct bpf_prog *new_prog, 9120 struct bpf_prog *old_prog, u32 flags) 9121 { 9122 unsigned int num_modes = hweight32(flags & XDP_FLAGS_MODES); 9123 struct bpf_prog *cur_prog; 9124 struct net_device *upper; 9125 struct list_head *iter; 9126 enum bpf_xdp_mode mode; 9127 bpf_op_t bpf_op; 9128 int err; 9129 9130 ASSERT_RTNL(); 9131 9132 /* either link or prog attachment, never both */ 9133 if (link && (new_prog || old_prog)) 9134 return -EINVAL; 9135 /* link supports only XDP mode flags */ 9136 if (link && (flags & ~XDP_FLAGS_MODES)) { 9137 NL_SET_ERR_MSG(extack, "Invalid XDP flags for BPF link attachment"); 9138 return -EINVAL; 9139 } 9140 /* just one XDP mode bit should be set, zero defaults to drv/skb mode */ 9141 if (num_modes > 1) { 9142 NL_SET_ERR_MSG(extack, "Only one XDP mode flag can be set"); 9143 return -EINVAL; 9144 } 9145 /* avoid ambiguity if offload + drv/skb mode progs are both loaded */ 9146 if (!num_modes && dev_xdp_prog_count(dev) > 1) { 9147 NL_SET_ERR_MSG(extack, 9148 "More than one program loaded, unset mode is ambiguous"); 9149 return -EINVAL; 9150 } 9151 /* old_prog != NULL implies XDP_FLAGS_REPLACE is set */ 9152 if (old_prog && !(flags & XDP_FLAGS_REPLACE)) { 9153 NL_SET_ERR_MSG(extack, "XDP_FLAGS_REPLACE is not specified"); 9154 return -EINVAL; 9155 } 9156 9157 mode = dev_xdp_mode(dev, flags); 9158 /* can't replace attached link */ 9159 if (dev_xdp_link(dev, mode)) { 9160 NL_SET_ERR_MSG(extack, "Can't replace active BPF XDP link"); 9161 return -EBUSY; 9162 } 9163 9164 /* don't allow if an upper device already has a program */ 9165 netdev_for_each_upper_dev_rcu(dev, upper, iter) { 9166 if (dev_xdp_prog_count(upper) > 0) { 9167 NL_SET_ERR_MSG(extack, "Cannot attach when an upper device already has a program"); 9168 return -EEXIST; 9169 } 9170 } 9171 9172 cur_prog = dev_xdp_prog(dev, mode); 9173 /* can't replace attached prog with link */ 9174 if (link && cur_prog) { 9175 NL_SET_ERR_MSG(extack, "Can't replace active XDP program with BPF link"); 9176 return -EBUSY; 9177 } 9178 if ((flags & XDP_FLAGS_REPLACE) && cur_prog != old_prog) { 9179 NL_SET_ERR_MSG(extack, "Active program does not match expected"); 9180 return -EEXIST; 9181 } 9182 9183 /* put effective new program into new_prog */ 9184 if (link) 9185 new_prog = link->link.prog; 9186 9187 if (new_prog) { 9188 bool offload = mode == XDP_MODE_HW; 9189 enum bpf_xdp_mode other_mode = mode == XDP_MODE_SKB 9190 ? XDP_MODE_DRV : XDP_MODE_SKB; 9191 9192 if ((flags & XDP_FLAGS_UPDATE_IF_NOEXIST) && cur_prog) { 9193 NL_SET_ERR_MSG(extack, "XDP program already attached"); 9194 return -EBUSY; 9195 } 9196 if (!offload && dev_xdp_prog(dev, other_mode)) { 9197 NL_SET_ERR_MSG(extack, "Native and generic XDP can't be active at the same time"); 9198 return -EEXIST; 9199 } 9200 if (!offload && bpf_prog_is_offloaded(new_prog->aux)) { 9201 NL_SET_ERR_MSG(extack, "Using offloaded program without HW_MODE flag is not supported"); 9202 return -EINVAL; 9203 } 9204 if (bpf_prog_is_dev_bound(new_prog->aux) && !bpf_offload_dev_match(new_prog, dev)) { 9205 NL_SET_ERR_MSG(extack, "Program bound to different device"); 9206 return -EINVAL; 9207 } 9208 if (new_prog->expected_attach_type == BPF_XDP_DEVMAP) { 9209 NL_SET_ERR_MSG(extack, "BPF_XDP_DEVMAP programs can not be attached to a device"); 9210 return -EINVAL; 9211 } 9212 if (new_prog->expected_attach_type == BPF_XDP_CPUMAP) { 9213 NL_SET_ERR_MSG(extack, "BPF_XDP_CPUMAP programs can not be attached to a device"); 9214 return -EINVAL; 9215 } 9216 } 9217 9218 /* don't call drivers if the effective program didn't change */ 9219 if (new_prog != cur_prog) { 9220 bpf_op = dev_xdp_bpf_op(dev, mode); 9221 if (!bpf_op) { 9222 NL_SET_ERR_MSG(extack, "Underlying driver does not support XDP in native mode"); 9223 return -EOPNOTSUPP; 9224 } 9225 9226 err = dev_xdp_install(dev, mode, bpf_op, extack, flags, new_prog); 9227 if (err) 9228 return err; 9229 } 9230 9231 if (link) 9232 dev_xdp_set_link(dev, mode, link); 9233 else 9234 dev_xdp_set_prog(dev, mode, new_prog); 9235 if (cur_prog) 9236 bpf_prog_put(cur_prog); 9237 9238 return 0; 9239 } 9240 9241 static int dev_xdp_attach_link(struct net_device *dev, 9242 struct netlink_ext_ack *extack, 9243 struct bpf_xdp_link *link) 9244 { 9245 return dev_xdp_attach(dev, extack, link, NULL, NULL, link->flags); 9246 } 9247 9248 static int dev_xdp_detach_link(struct net_device *dev, 9249 struct netlink_ext_ack *extack, 9250 struct bpf_xdp_link *link) 9251 { 9252 enum bpf_xdp_mode mode; 9253 bpf_op_t bpf_op; 9254 9255 ASSERT_RTNL(); 9256 9257 mode = dev_xdp_mode(dev, link->flags); 9258 if (dev_xdp_link(dev, mode) != link) 9259 return -EINVAL; 9260 9261 bpf_op = dev_xdp_bpf_op(dev, mode); 9262 WARN_ON(dev_xdp_install(dev, mode, bpf_op, NULL, 0, NULL)); 9263 dev_xdp_set_link(dev, mode, NULL); 9264 return 0; 9265 } 9266 9267 static void bpf_xdp_link_release(struct bpf_link *link) 9268 { 9269 struct bpf_xdp_link *xdp_link = container_of(link, struct bpf_xdp_link, link); 9270 9271 rtnl_lock(); 9272 9273 /* if racing with net_device's tear down, xdp_link->dev might be 9274 * already NULL, in which case link was already auto-detached 9275 */ 9276 if (xdp_link->dev) { 9277 WARN_ON(dev_xdp_detach_link(xdp_link->dev, NULL, xdp_link)); 9278 xdp_link->dev = NULL; 9279 } 9280 9281 rtnl_unlock(); 9282 } 9283 9284 static int bpf_xdp_link_detach(struct bpf_link *link) 9285 { 9286 bpf_xdp_link_release(link); 9287 return 0; 9288 } 9289 9290 static void bpf_xdp_link_dealloc(struct bpf_link *link) 9291 { 9292 struct bpf_xdp_link *xdp_link = container_of(link, struct bpf_xdp_link, link); 9293 9294 kfree(xdp_link); 9295 } 9296 9297 static void bpf_xdp_link_show_fdinfo(const struct bpf_link *link, 9298 struct seq_file *seq) 9299 { 9300 struct bpf_xdp_link *xdp_link = container_of(link, struct bpf_xdp_link, link); 9301 u32 ifindex = 0; 9302 9303 rtnl_lock(); 9304 if (xdp_link->dev) 9305 ifindex = xdp_link->dev->ifindex; 9306 rtnl_unlock(); 9307 9308 seq_printf(seq, "ifindex:\t%u\n", ifindex); 9309 } 9310 9311 static int bpf_xdp_link_fill_link_info(const struct bpf_link *link, 9312 struct bpf_link_info *info) 9313 { 9314 struct bpf_xdp_link *xdp_link = container_of(link, struct bpf_xdp_link, link); 9315 u32 ifindex = 0; 9316 9317 rtnl_lock(); 9318 if (xdp_link->dev) 9319 ifindex = xdp_link->dev->ifindex; 9320 rtnl_unlock(); 9321 9322 info->xdp.ifindex = ifindex; 9323 return 0; 9324 } 9325 9326 static int bpf_xdp_link_update(struct bpf_link *link, struct bpf_prog *new_prog, 9327 struct bpf_prog *old_prog) 9328 { 9329 struct bpf_xdp_link *xdp_link = container_of(link, struct bpf_xdp_link, link); 9330 enum bpf_xdp_mode mode; 9331 bpf_op_t bpf_op; 9332 int err = 0; 9333 9334 rtnl_lock(); 9335 9336 /* link might have been auto-released already, so fail */ 9337 if (!xdp_link->dev) { 9338 err = -ENOLINK; 9339 goto out_unlock; 9340 } 9341 9342 if (old_prog && link->prog != old_prog) { 9343 err = -EPERM; 9344 goto out_unlock; 9345 } 9346 old_prog = link->prog; 9347 if (old_prog->type != new_prog->type || 9348 old_prog->expected_attach_type != new_prog->expected_attach_type) { 9349 err = -EINVAL; 9350 goto out_unlock; 9351 } 9352 9353 if (old_prog == new_prog) { 9354 /* no-op, don't disturb drivers */ 9355 bpf_prog_put(new_prog); 9356 goto out_unlock; 9357 } 9358 9359 mode = dev_xdp_mode(xdp_link->dev, xdp_link->flags); 9360 bpf_op = dev_xdp_bpf_op(xdp_link->dev, mode); 9361 err = dev_xdp_install(xdp_link->dev, mode, bpf_op, NULL, 9362 xdp_link->flags, new_prog); 9363 if (err) 9364 goto out_unlock; 9365 9366 old_prog = xchg(&link->prog, new_prog); 9367 bpf_prog_put(old_prog); 9368 9369 out_unlock: 9370 rtnl_unlock(); 9371 return err; 9372 } 9373 9374 static const struct bpf_link_ops bpf_xdp_link_lops = { 9375 .release = bpf_xdp_link_release, 9376 .dealloc = bpf_xdp_link_dealloc, 9377 .detach = bpf_xdp_link_detach, 9378 .show_fdinfo = bpf_xdp_link_show_fdinfo, 9379 .fill_link_info = bpf_xdp_link_fill_link_info, 9380 .update_prog = bpf_xdp_link_update, 9381 }; 9382 9383 int bpf_xdp_link_attach(const union bpf_attr *attr, struct bpf_prog *prog) 9384 { 9385 struct net *net = current->nsproxy->net_ns; 9386 struct bpf_link_primer link_primer; 9387 struct bpf_xdp_link *link; 9388 struct net_device *dev; 9389 int err, fd; 9390 9391 rtnl_lock(); 9392 dev = dev_get_by_index(net, attr->link_create.target_ifindex); 9393 if (!dev) { 9394 rtnl_unlock(); 9395 return -EINVAL; 9396 } 9397 9398 link = kzalloc(sizeof(*link), GFP_USER); 9399 if (!link) { 9400 err = -ENOMEM; 9401 goto unlock; 9402 } 9403 9404 bpf_link_init(&link->link, BPF_LINK_TYPE_XDP, &bpf_xdp_link_lops, prog); 9405 link->dev = dev; 9406 link->flags = attr->link_create.flags; 9407 9408 err = bpf_link_prime(&link->link, &link_primer); 9409 if (err) { 9410 kfree(link); 9411 goto unlock; 9412 } 9413 9414 err = dev_xdp_attach_link(dev, NULL, link); 9415 rtnl_unlock(); 9416 9417 if (err) { 9418 link->dev = NULL; 9419 bpf_link_cleanup(&link_primer); 9420 goto out_put_dev; 9421 } 9422 9423 fd = bpf_link_settle(&link_primer); 9424 /* link itself doesn't hold dev's refcnt to not complicate shutdown */ 9425 dev_put(dev); 9426 return fd; 9427 9428 unlock: 9429 rtnl_unlock(); 9430 9431 out_put_dev: 9432 dev_put(dev); 9433 return err; 9434 } 9435 9436 /** 9437 * dev_change_xdp_fd - set or clear a bpf program for a device rx path 9438 * @dev: device 9439 * @extack: netlink extended ack 9440 * @fd: new program fd or negative value to clear 9441 * @expected_fd: old program fd that userspace expects to replace or clear 9442 * @flags: xdp-related flags 9443 * 9444 * Set or clear a bpf program for a device 9445 */ 9446 int dev_change_xdp_fd(struct net_device *dev, struct netlink_ext_ack *extack, 9447 int fd, int expected_fd, u32 flags) 9448 { 9449 enum bpf_xdp_mode mode = dev_xdp_mode(dev, flags); 9450 struct bpf_prog *new_prog = NULL, *old_prog = NULL; 9451 int err; 9452 9453 ASSERT_RTNL(); 9454 9455 if (fd >= 0) { 9456 new_prog = bpf_prog_get_type_dev(fd, BPF_PROG_TYPE_XDP, 9457 mode != XDP_MODE_SKB); 9458 if (IS_ERR(new_prog)) 9459 return PTR_ERR(new_prog); 9460 } 9461 9462 if (expected_fd >= 0) { 9463 old_prog = bpf_prog_get_type_dev(expected_fd, BPF_PROG_TYPE_XDP, 9464 mode != XDP_MODE_SKB); 9465 if (IS_ERR(old_prog)) { 9466 err = PTR_ERR(old_prog); 9467 old_prog = NULL; 9468 goto err_out; 9469 } 9470 } 9471 9472 err = dev_xdp_attach(dev, extack, NULL, new_prog, old_prog, flags); 9473 9474 err_out: 9475 if (err && new_prog) 9476 bpf_prog_put(new_prog); 9477 if (old_prog) 9478 bpf_prog_put(old_prog); 9479 return err; 9480 } 9481 9482 /** 9483 * dev_new_index - allocate an ifindex 9484 * @net: the applicable net namespace 9485 * 9486 * Returns a suitable unique value for a new device interface 9487 * number. The caller must hold the rtnl semaphore or the 9488 * dev_base_lock to be sure it remains unique. 9489 */ 9490 static int dev_new_index(struct net *net) 9491 { 9492 int ifindex = net->ifindex; 9493 9494 for (;;) { 9495 if (++ifindex <= 0) 9496 ifindex = 1; 9497 if (!__dev_get_by_index(net, ifindex)) 9498 return net->ifindex = ifindex; 9499 } 9500 } 9501 9502 /* Delayed registration/unregisteration */ 9503 LIST_HEAD(net_todo_list); 9504 DECLARE_WAIT_QUEUE_HEAD(netdev_unregistering_wq); 9505 9506 static void net_set_todo(struct net_device *dev) 9507 { 9508 list_add_tail(&dev->todo_list, &net_todo_list); 9509 atomic_inc(&dev_net(dev)->dev_unreg_count); 9510 } 9511 9512 static netdev_features_t netdev_sync_upper_features(struct net_device *lower, 9513 struct net_device *upper, netdev_features_t features) 9514 { 9515 netdev_features_t upper_disables = NETIF_F_UPPER_DISABLES; 9516 netdev_features_t feature; 9517 int feature_bit; 9518 9519 for_each_netdev_feature(upper_disables, feature_bit) { 9520 feature = __NETIF_F_BIT(feature_bit); 9521 if (!(upper->wanted_features & feature) 9522 && (features & feature)) { 9523 netdev_dbg(lower, "Dropping feature %pNF, upper dev %s has it off.\n", 9524 &feature, upper->name); 9525 features &= ~feature; 9526 } 9527 } 9528 9529 return features; 9530 } 9531 9532 static void netdev_sync_lower_features(struct net_device *upper, 9533 struct net_device *lower, netdev_features_t features) 9534 { 9535 netdev_features_t upper_disables = NETIF_F_UPPER_DISABLES; 9536 netdev_features_t feature; 9537 int feature_bit; 9538 9539 for_each_netdev_feature(upper_disables, feature_bit) { 9540 feature = __NETIF_F_BIT(feature_bit); 9541 if (!(features & feature) && (lower->features & feature)) { 9542 netdev_dbg(upper, "Disabling feature %pNF on lower dev %s.\n", 9543 &feature, lower->name); 9544 lower->wanted_features &= ~feature; 9545 __netdev_update_features(lower); 9546 9547 if (unlikely(lower->features & feature)) 9548 netdev_WARN(upper, "failed to disable %pNF on %s!\n", 9549 &feature, lower->name); 9550 else 9551 netdev_features_change(lower); 9552 } 9553 } 9554 } 9555 9556 static netdev_features_t netdev_fix_features(struct net_device *dev, 9557 netdev_features_t features) 9558 { 9559 /* Fix illegal checksum combinations */ 9560 if ((features & NETIF_F_HW_CSUM) && 9561 (features & (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))) { 9562 netdev_warn(dev, "mixed HW and IP checksum settings.\n"); 9563 features &= ~(NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM); 9564 } 9565 9566 /* TSO requires that SG is present as well. */ 9567 if ((features & NETIF_F_ALL_TSO) && !(features & NETIF_F_SG)) { 9568 netdev_dbg(dev, "Dropping TSO features since no SG feature.\n"); 9569 features &= ~NETIF_F_ALL_TSO; 9570 } 9571 9572 if ((features & NETIF_F_TSO) && !(features & NETIF_F_HW_CSUM) && 9573 !(features & NETIF_F_IP_CSUM)) { 9574 netdev_dbg(dev, "Dropping TSO features since no CSUM feature.\n"); 9575 features &= ~NETIF_F_TSO; 9576 features &= ~NETIF_F_TSO_ECN; 9577 } 9578 9579 if ((features & NETIF_F_TSO6) && !(features & NETIF_F_HW_CSUM) && 9580 !(features & NETIF_F_IPV6_CSUM)) { 9581 netdev_dbg(dev, "Dropping TSO6 features since no CSUM feature.\n"); 9582 features &= ~NETIF_F_TSO6; 9583 } 9584 9585 /* TSO with IPv4 ID mangling requires IPv4 TSO be enabled */ 9586 if ((features & NETIF_F_TSO_MANGLEID) && !(features & NETIF_F_TSO)) 9587 features &= ~NETIF_F_TSO_MANGLEID; 9588 9589 /* TSO ECN requires that TSO is present as well. */ 9590 if ((features & NETIF_F_ALL_TSO) == NETIF_F_TSO_ECN) 9591 features &= ~NETIF_F_TSO_ECN; 9592 9593 /* Software GSO depends on SG. */ 9594 if ((features & NETIF_F_GSO) && !(features & NETIF_F_SG)) { 9595 netdev_dbg(dev, "Dropping NETIF_F_GSO since no SG feature.\n"); 9596 features &= ~NETIF_F_GSO; 9597 } 9598 9599 /* GSO partial features require GSO partial be set */ 9600 if ((features & dev->gso_partial_features) && 9601 !(features & NETIF_F_GSO_PARTIAL)) { 9602 netdev_dbg(dev, 9603 "Dropping partially supported GSO features since no GSO partial.\n"); 9604 features &= ~dev->gso_partial_features; 9605 } 9606 9607 if (!(features & NETIF_F_RXCSUM)) { 9608 /* NETIF_F_GRO_HW implies doing RXCSUM since every packet 9609 * successfully merged by hardware must also have the 9610 * checksum verified by hardware. If the user does not 9611 * want to enable RXCSUM, logically, we should disable GRO_HW. 9612 */ 9613 if (features & NETIF_F_GRO_HW) { 9614 netdev_dbg(dev, "Dropping NETIF_F_GRO_HW since no RXCSUM feature.\n"); 9615 features &= ~NETIF_F_GRO_HW; 9616 } 9617 } 9618 9619 /* LRO/HW-GRO features cannot be combined with RX-FCS */ 9620 if (features & NETIF_F_RXFCS) { 9621 if (features & NETIF_F_LRO) { 9622 netdev_dbg(dev, "Dropping LRO feature since RX-FCS is requested.\n"); 9623 features &= ~NETIF_F_LRO; 9624 } 9625 9626 if (features & NETIF_F_GRO_HW) { 9627 netdev_dbg(dev, "Dropping HW-GRO feature since RX-FCS is requested.\n"); 9628 features &= ~NETIF_F_GRO_HW; 9629 } 9630 } 9631 9632 if ((features & NETIF_F_GRO_HW) && (features & NETIF_F_LRO)) { 9633 netdev_dbg(dev, "Dropping LRO feature since HW-GRO is requested.\n"); 9634 features &= ~NETIF_F_LRO; 9635 } 9636 9637 if (features & NETIF_F_HW_TLS_TX) { 9638 bool ip_csum = (features & (NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM)) == 9639 (NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM); 9640 bool hw_csum = features & NETIF_F_HW_CSUM; 9641 9642 if (!ip_csum && !hw_csum) { 9643 netdev_dbg(dev, "Dropping TLS TX HW offload feature since no CSUM feature.\n"); 9644 features &= ~NETIF_F_HW_TLS_TX; 9645 } 9646 } 9647 9648 if ((features & NETIF_F_HW_TLS_RX) && !(features & NETIF_F_RXCSUM)) { 9649 netdev_dbg(dev, "Dropping TLS RX HW offload feature since no RXCSUM feature.\n"); 9650 features &= ~NETIF_F_HW_TLS_RX; 9651 } 9652 9653 return features; 9654 } 9655 9656 int __netdev_update_features(struct net_device *dev) 9657 { 9658 struct net_device *upper, *lower; 9659 netdev_features_t features; 9660 struct list_head *iter; 9661 int err = -1; 9662 9663 ASSERT_RTNL(); 9664 9665 features = netdev_get_wanted_features(dev); 9666 9667 if (dev->netdev_ops->ndo_fix_features) 9668 features = dev->netdev_ops->ndo_fix_features(dev, features); 9669 9670 /* driver might be less strict about feature dependencies */ 9671 features = netdev_fix_features(dev, features); 9672 9673 /* some features can't be enabled if they're off on an upper device */ 9674 netdev_for_each_upper_dev_rcu(dev, upper, iter) 9675 features = netdev_sync_upper_features(dev, upper, features); 9676 9677 if (dev->features == features) 9678 goto sync_lower; 9679 9680 netdev_dbg(dev, "Features changed: %pNF -> %pNF\n", 9681 &dev->features, &features); 9682 9683 if (dev->netdev_ops->ndo_set_features) 9684 err = dev->netdev_ops->ndo_set_features(dev, features); 9685 else 9686 err = 0; 9687 9688 if (unlikely(err < 0)) { 9689 netdev_err(dev, 9690 "set_features() failed (%d); wanted %pNF, left %pNF\n", 9691 err, &features, &dev->features); 9692 /* return non-0 since some features might have changed and 9693 * it's better to fire a spurious notification than miss it 9694 */ 9695 return -1; 9696 } 9697 9698 sync_lower: 9699 /* some features must be disabled on lower devices when disabled 9700 * on an upper device (think: bonding master or bridge) 9701 */ 9702 netdev_for_each_lower_dev(dev, lower, iter) 9703 netdev_sync_lower_features(dev, lower, features); 9704 9705 if (!err) { 9706 netdev_features_t diff = features ^ dev->features; 9707 9708 if (diff & NETIF_F_RX_UDP_TUNNEL_PORT) { 9709 /* udp_tunnel_{get,drop}_rx_info both need 9710 * NETIF_F_RX_UDP_TUNNEL_PORT enabled on the 9711 * device, or they won't do anything. 9712 * Thus we need to update dev->features 9713 * *before* calling udp_tunnel_get_rx_info, 9714 * but *after* calling udp_tunnel_drop_rx_info. 9715 */ 9716 if (features & NETIF_F_RX_UDP_TUNNEL_PORT) { 9717 dev->features = features; 9718 udp_tunnel_get_rx_info(dev); 9719 } else { 9720 udp_tunnel_drop_rx_info(dev); 9721 } 9722 } 9723 9724 if (diff & NETIF_F_HW_VLAN_CTAG_FILTER) { 9725 if (features & NETIF_F_HW_VLAN_CTAG_FILTER) { 9726 dev->features = features; 9727 err |= vlan_get_rx_ctag_filter_info(dev); 9728 } else { 9729 vlan_drop_rx_ctag_filter_info(dev); 9730 } 9731 } 9732 9733 if (diff & NETIF_F_HW_VLAN_STAG_FILTER) { 9734 if (features & NETIF_F_HW_VLAN_STAG_FILTER) { 9735 dev->features = features; 9736 err |= vlan_get_rx_stag_filter_info(dev); 9737 } else { 9738 vlan_drop_rx_stag_filter_info(dev); 9739 } 9740 } 9741 9742 dev->features = features; 9743 } 9744 9745 return err < 0 ? 0 : 1; 9746 } 9747 9748 /** 9749 * netdev_update_features - recalculate device features 9750 * @dev: the device to check 9751 * 9752 * Recalculate dev->features set and send notifications if it 9753 * has changed. Should be called after driver or hardware dependent 9754 * conditions might have changed that influence the features. 9755 */ 9756 void netdev_update_features(struct net_device *dev) 9757 { 9758 if (__netdev_update_features(dev)) 9759 netdev_features_change(dev); 9760 } 9761 EXPORT_SYMBOL(netdev_update_features); 9762 9763 /** 9764 * netdev_change_features - recalculate device features 9765 * @dev: the device to check 9766 * 9767 * Recalculate dev->features set and send notifications even 9768 * if they have not changed. Should be called instead of 9769 * netdev_update_features() if also dev->vlan_features might 9770 * have changed to allow the changes to be propagated to stacked 9771 * VLAN devices. 9772 */ 9773 void netdev_change_features(struct net_device *dev) 9774 { 9775 __netdev_update_features(dev); 9776 netdev_features_change(dev); 9777 } 9778 EXPORT_SYMBOL(netdev_change_features); 9779 9780 /** 9781 * netif_stacked_transfer_operstate - transfer operstate 9782 * @rootdev: the root or lower level device to transfer state from 9783 * @dev: the device to transfer operstate to 9784 * 9785 * Transfer operational state from root to device. This is normally 9786 * called when a stacking relationship exists between the root 9787 * device and the device(a leaf device). 9788 */ 9789 void netif_stacked_transfer_operstate(const struct net_device *rootdev, 9790 struct net_device *dev) 9791 { 9792 if (rootdev->operstate == IF_OPER_DORMANT) 9793 netif_dormant_on(dev); 9794 else 9795 netif_dormant_off(dev); 9796 9797 if (rootdev->operstate == IF_OPER_TESTING) 9798 netif_testing_on(dev); 9799 else 9800 netif_testing_off(dev); 9801 9802 if (netif_carrier_ok(rootdev)) 9803 netif_carrier_on(dev); 9804 else 9805 netif_carrier_off(dev); 9806 } 9807 EXPORT_SYMBOL(netif_stacked_transfer_operstate); 9808 9809 static int netif_alloc_rx_queues(struct net_device *dev) 9810 { 9811 unsigned int i, count = dev->num_rx_queues; 9812 struct netdev_rx_queue *rx; 9813 size_t sz = count * sizeof(*rx); 9814 int err = 0; 9815 9816 BUG_ON(count < 1); 9817 9818 rx = kvzalloc(sz, GFP_KERNEL_ACCOUNT | __GFP_RETRY_MAYFAIL); 9819 if (!rx) 9820 return -ENOMEM; 9821 9822 dev->_rx = rx; 9823 9824 for (i = 0; i < count; i++) { 9825 rx[i].dev = dev; 9826 9827 /* XDP RX-queue setup */ 9828 err = xdp_rxq_info_reg(&rx[i].xdp_rxq, dev, i, 0); 9829 if (err < 0) 9830 goto err_rxq_info; 9831 } 9832 return 0; 9833 9834 err_rxq_info: 9835 /* Rollback successful reg's and free other resources */ 9836 while (i--) 9837 xdp_rxq_info_unreg(&rx[i].xdp_rxq); 9838 kvfree(dev->_rx); 9839 dev->_rx = NULL; 9840 return err; 9841 } 9842 9843 static void netif_free_rx_queues(struct net_device *dev) 9844 { 9845 unsigned int i, count = dev->num_rx_queues; 9846 9847 /* netif_alloc_rx_queues alloc failed, resources have been unreg'ed */ 9848 if (!dev->_rx) 9849 return; 9850 9851 for (i = 0; i < count; i++) 9852 xdp_rxq_info_unreg(&dev->_rx[i].xdp_rxq); 9853 9854 kvfree(dev->_rx); 9855 } 9856 9857 static void netdev_init_one_queue(struct net_device *dev, 9858 struct netdev_queue *queue, void *_unused) 9859 { 9860 /* Initialize queue lock */ 9861 spin_lock_init(&queue->_xmit_lock); 9862 netdev_set_xmit_lockdep_class(&queue->_xmit_lock, dev->type); 9863 queue->xmit_lock_owner = -1; 9864 netdev_queue_numa_node_write(queue, NUMA_NO_NODE); 9865 queue->dev = dev; 9866 #ifdef CONFIG_BQL 9867 dql_init(&queue->dql, HZ); 9868 #endif 9869 } 9870 9871 static void netif_free_tx_queues(struct net_device *dev) 9872 { 9873 kvfree(dev->_tx); 9874 } 9875 9876 static int netif_alloc_netdev_queues(struct net_device *dev) 9877 { 9878 unsigned int count = dev->num_tx_queues; 9879 struct netdev_queue *tx; 9880 size_t sz = count * sizeof(*tx); 9881 9882 if (count < 1 || count > 0xffff) 9883 return -EINVAL; 9884 9885 tx = kvzalloc(sz, GFP_KERNEL_ACCOUNT | __GFP_RETRY_MAYFAIL); 9886 if (!tx) 9887 return -ENOMEM; 9888 9889 dev->_tx = tx; 9890 9891 netdev_for_each_tx_queue(dev, netdev_init_one_queue, NULL); 9892 spin_lock_init(&dev->tx_global_lock); 9893 9894 return 0; 9895 } 9896 9897 void netif_tx_stop_all_queues(struct net_device *dev) 9898 { 9899 unsigned int i; 9900 9901 for (i = 0; i < dev->num_tx_queues; i++) { 9902 struct netdev_queue *txq = netdev_get_tx_queue(dev, i); 9903 9904 netif_tx_stop_queue(txq); 9905 } 9906 } 9907 EXPORT_SYMBOL(netif_tx_stop_all_queues); 9908 9909 /** 9910 * register_netdevice() - register a network device 9911 * @dev: device to register 9912 * 9913 * Take a prepared network device structure and make it externally accessible. 9914 * A %NETDEV_REGISTER message is sent to the netdev notifier chain. 9915 * Callers must hold the rtnl lock - you may want register_netdev() 9916 * instead of this. 9917 */ 9918 int register_netdevice(struct net_device *dev) 9919 { 9920 int ret; 9921 struct net *net = dev_net(dev); 9922 9923 BUILD_BUG_ON(sizeof(netdev_features_t) * BITS_PER_BYTE < 9924 NETDEV_FEATURE_COUNT); 9925 BUG_ON(dev_boot_phase); 9926 ASSERT_RTNL(); 9927 9928 might_sleep(); 9929 9930 /* When net_device's are persistent, this will be fatal. */ 9931 BUG_ON(dev->reg_state != NETREG_UNINITIALIZED); 9932 BUG_ON(!net); 9933 9934 ret = ethtool_check_ops(dev->ethtool_ops); 9935 if (ret) 9936 return ret; 9937 9938 spin_lock_init(&dev->addr_list_lock); 9939 netdev_set_addr_lockdep_class(dev); 9940 9941 ret = dev_get_valid_name(net, dev, dev->name); 9942 if (ret < 0) 9943 goto out; 9944 9945 ret = -ENOMEM; 9946 dev->name_node = netdev_name_node_head_alloc(dev); 9947 if (!dev->name_node) 9948 goto out; 9949 9950 /* Init, if this function is available */ 9951 if (dev->netdev_ops->ndo_init) { 9952 ret = dev->netdev_ops->ndo_init(dev); 9953 if (ret) { 9954 if (ret > 0) 9955 ret = -EIO; 9956 goto err_free_name; 9957 } 9958 } 9959 9960 if (((dev->hw_features | dev->features) & 9961 NETIF_F_HW_VLAN_CTAG_FILTER) && 9962 (!dev->netdev_ops->ndo_vlan_rx_add_vid || 9963 !dev->netdev_ops->ndo_vlan_rx_kill_vid)) { 9964 netdev_WARN(dev, "Buggy VLAN acceleration in driver!\n"); 9965 ret = -EINVAL; 9966 goto err_uninit; 9967 } 9968 9969 ret = -EBUSY; 9970 if (!dev->ifindex) 9971 dev->ifindex = dev_new_index(net); 9972 else if (__dev_get_by_index(net, dev->ifindex)) 9973 goto err_uninit; 9974 9975 /* Transfer changeable features to wanted_features and enable 9976 * software offloads (GSO and GRO). 9977 */ 9978 dev->hw_features |= (NETIF_F_SOFT_FEATURES | NETIF_F_SOFT_FEATURES_OFF); 9979 dev->features |= NETIF_F_SOFT_FEATURES; 9980 9981 if (dev->udp_tunnel_nic_info) { 9982 dev->features |= NETIF_F_RX_UDP_TUNNEL_PORT; 9983 dev->hw_features |= NETIF_F_RX_UDP_TUNNEL_PORT; 9984 } 9985 9986 dev->wanted_features = dev->features & dev->hw_features; 9987 9988 if (!(dev->flags & IFF_LOOPBACK)) 9989 dev->hw_features |= NETIF_F_NOCACHE_COPY; 9990 9991 /* If IPv4 TCP segmentation offload is supported we should also 9992 * allow the device to enable segmenting the frame with the option 9993 * of ignoring a static IP ID value. This doesn't enable the 9994 * feature itself but allows the user to enable it later. 9995 */ 9996 if (dev->hw_features & NETIF_F_TSO) 9997 dev->hw_features |= NETIF_F_TSO_MANGLEID; 9998 if (dev->vlan_features & NETIF_F_TSO) 9999 dev->vlan_features |= NETIF_F_TSO_MANGLEID; 10000 if (dev->mpls_features & NETIF_F_TSO) 10001 dev->mpls_features |= NETIF_F_TSO_MANGLEID; 10002 if (dev->hw_enc_features & NETIF_F_TSO) 10003 dev->hw_enc_features |= NETIF_F_TSO_MANGLEID; 10004 10005 /* Make NETIF_F_HIGHDMA inheritable to VLAN devices. 10006 */ 10007 dev->vlan_features |= NETIF_F_HIGHDMA; 10008 10009 /* Make NETIF_F_SG inheritable to tunnel devices. 10010 */ 10011 dev->hw_enc_features |= NETIF_F_SG | NETIF_F_GSO_PARTIAL; 10012 10013 /* Make NETIF_F_SG inheritable to MPLS. 10014 */ 10015 dev->mpls_features |= NETIF_F_SG; 10016 10017 ret = call_netdevice_notifiers(NETDEV_POST_INIT, dev); 10018 ret = notifier_to_errno(ret); 10019 if (ret) 10020 goto err_uninit; 10021 10022 ret = netdev_register_kobject(dev); 10023 write_lock(&dev_base_lock); 10024 dev->reg_state = ret ? NETREG_UNREGISTERED : NETREG_REGISTERED; 10025 write_unlock(&dev_base_lock); 10026 if (ret) 10027 goto err_uninit_notify; 10028 10029 __netdev_update_features(dev); 10030 10031 /* 10032 * Default initial state at registry is that the 10033 * device is present. 10034 */ 10035 10036 set_bit(__LINK_STATE_PRESENT, &dev->state); 10037 10038 linkwatch_init_dev(dev); 10039 10040 dev_init_scheduler(dev); 10041 10042 netdev_hold(dev, &dev->dev_registered_tracker, GFP_KERNEL); 10043 list_netdevice(dev); 10044 10045 add_device_randomness(dev->dev_addr, dev->addr_len); 10046 10047 /* If the device has permanent device address, driver should 10048 * set dev_addr and also addr_assign_type should be set to 10049 * NET_ADDR_PERM (default value). 10050 */ 10051 if (dev->addr_assign_type == NET_ADDR_PERM) 10052 memcpy(dev->perm_addr, dev->dev_addr, dev->addr_len); 10053 10054 /* Notify protocols, that a new device appeared. */ 10055 ret = call_netdevice_notifiers(NETDEV_REGISTER, dev); 10056 ret = notifier_to_errno(ret); 10057 if (ret) { 10058 /* Expect explicit free_netdev() on failure */ 10059 dev->needs_free_netdev = false; 10060 unregister_netdevice_queue(dev, NULL); 10061 goto out; 10062 } 10063 /* 10064 * Prevent userspace races by waiting until the network 10065 * device is fully setup before sending notifications. 10066 */ 10067 if (!dev->rtnl_link_ops || 10068 dev->rtnl_link_state == RTNL_LINK_INITIALIZED) 10069 rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U, GFP_KERNEL, 0, NULL); 10070 10071 out: 10072 return ret; 10073 10074 err_uninit_notify: 10075 call_netdevice_notifiers(NETDEV_PRE_UNINIT, dev); 10076 err_uninit: 10077 if (dev->netdev_ops->ndo_uninit) 10078 dev->netdev_ops->ndo_uninit(dev); 10079 if (dev->priv_destructor) 10080 dev->priv_destructor(dev); 10081 err_free_name: 10082 netdev_name_node_free(dev->name_node); 10083 goto out; 10084 } 10085 EXPORT_SYMBOL(register_netdevice); 10086 10087 /** 10088 * init_dummy_netdev - init a dummy network device for NAPI 10089 * @dev: device to init 10090 * 10091 * This takes a network device structure and initialize the minimum 10092 * amount of fields so it can be used to schedule NAPI polls without 10093 * registering a full blown interface. This is to be used by drivers 10094 * that need to tie several hardware interfaces to a single NAPI 10095 * poll scheduler due to HW limitations. 10096 */ 10097 int init_dummy_netdev(struct net_device *dev) 10098 { 10099 /* Clear everything. Note we don't initialize spinlocks 10100 * are they aren't supposed to be taken by any of the 10101 * NAPI code and this dummy netdev is supposed to be 10102 * only ever used for NAPI polls 10103 */ 10104 memset(dev, 0, sizeof(struct net_device)); 10105 10106 /* make sure we BUG if trying to hit standard 10107 * register/unregister code path 10108 */ 10109 dev->reg_state = NETREG_DUMMY; 10110 10111 /* NAPI wants this */ 10112 INIT_LIST_HEAD(&dev->napi_list); 10113 10114 /* a dummy interface is started by default */ 10115 set_bit(__LINK_STATE_PRESENT, &dev->state); 10116 set_bit(__LINK_STATE_START, &dev->state); 10117 10118 /* napi_busy_loop stats accounting wants this */ 10119 dev_net_set(dev, &init_net); 10120 10121 /* Note : We dont allocate pcpu_refcnt for dummy devices, 10122 * because users of this 'device' dont need to change 10123 * its refcount. 10124 */ 10125 10126 return 0; 10127 } 10128 EXPORT_SYMBOL_GPL(init_dummy_netdev); 10129 10130 10131 /** 10132 * register_netdev - register a network device 10133 * @dev: device to register 10134 * 10135 * Take a completed network device structure and add it to the kernel 10136 * interfaces. A %NETDEV_REGISTER message is sent to the netdev notifier 10137 * chain. 0 is returned on success. A negative errno code is returned 10138 * on a failure to set up the device, or if the name is a duplicate. 10139 * 10140 * This is a wrapper around register_netdevice that takes the rtnl semaphore 10141 * and expands the device name if you passed a format string to 10142 * alloc_netdev. 10143 */ 10144 int register_netdev(struct net_device *dev) 10145 { 10146 int err; 10147 10148 if (rtnl_lock_killable()) 10149 return -EINTR; 10150 err = register_netdevice(dev); 10151 rtnl_unlock(); 10152 return err; 10153 } 10154 EXPORT_SYMBOL(register_netdev); 10155 10156 int netdev_refcnt_read(const struct net_device *dev) 10157 { 10158 #ifdef CONFIG_PCPU_DEV_REFCNT 10159 int i, refcnt = 0; 10160 10161 for_each_possible_cpu(i) 10162 refcnt += *per_cpu_ptr(dev->pcpu_refcnt, i); 10163 return refcnt; 10164 #else 10165 return refcount_read(&dev->dev_refcnt); 10166 #endif 10167 } 10168 EXPORT_SYMBOL(netdev_refcnt_read); 10169 10170 int netdev_unregister_timeout_secs __read_mostly = 10; 10171 10172 #define WAIT_REFS_MIN_MSECS 1 10173 #define WAIT_REFS_MAX_MSECS 250 10174 /** 10175 * netdev_wait_allrefs_any - wait until all references are gone. 10176 * @list: list of net_devices to wait on 10177 * 10178 * This is called when unregistering network devices. 10179 * 10180 * Any protocol or device that holds a reference should register 10181 * for netdevice notification, and cleanup and put back the 10182 * reference if they receive an UNREGISTER event. 10183 * We can get stuck here if buggy protocols don't correctly 10184 * call dev_put. 10185 */ 10186 static struct net_device *netdev_wait_allrefs_any(struct list_head *list) 10187 { 10188 unsigned long rebroadcast_time, warning_time; 10189 struct net_device *dev; 10190 int wait = 0; 10191 10192 rebroadcast_time = warning_time = jiffies; 10193 10194 list_for_each_entry(dev, list, todo_list) 10195 if (netdev_refcnt_read(dev) == 1) 10196 return dev; 10197 10198 while (true) { 10199 if (time_after(jiffies, rebroadcast_time + 1 * HZ)) { 10200 rtnl_lock(); 10201 10202 /* Rebroadcast unregister notification */ 10203 list_for_each_entry(dev, list, todo_list) 10204 call_netdevice_notifiers(NETDEV_UNREGISTER, dev); 10205 10206 __rtnl_unlock(); 10207 rcu_barrier(); 10208 rtnl_lock(); 10209 10210 list_for_each_entry(dev, list, todo_list) 10211 if (test_bit(__LINK_STATE_LINKWATCH_PENDING, 10212 &dev->state)) { 10213 /* We must not have linkwatch events 10214 * pending on unregister. If this 10215 * happens, we simply run the queue 10216 * unscheduled, resulting in a noop 10217 * for this device. 10218 */ 10219 linkwatch_run_queue(); 10220 break; 10221 } 10222 10223 __rtnl_unlock(); 10224 10225 rebroadcast_time = jiffies; 10226 } 10227 10228 if (!wait) { 10229 rcu_barrier(); 10230 wait = WAIT_REFS_MIN_MSECS; 10231 } else { 10232 msleep(wait); 10233 wait = min(wait << 1, WAIT_REFS_MAX_MSECS); 10234 } 10235 10236 list_for_each_entry(dev, list, todo_list) 10237 if (netdev_refcnt_read(dev) == 1) 10238 return dev; 10239 10240 if (time_after(jiffies, warning_time + 10241 READ_ONCE(netdev_unregister_timeout_secs) * HZ)) { 10242 list_for_each_entry(dev, list, todo_list) { 10243 pr_emerg("unregister_netdevice: waiting for %s to become free. Usage count = %d\n", 10244 dev->name, netdev_refcnt_read(dev)); 10245 ref_tracker_dir_print(&dev->refcnt_tracker, 10); 10246 } 10247 10248 warning_time = jiffies; 10249 } 10250 } 10251 } 10252 10253 /* The sequence is: 10254 * 10255 * rtnl_lock(); 10256 * ... 10257 * register_netdevice(x1); 10258 * register_netdevice(x2); 10259 * ... 10260 * unregister_netdevice(y1); 10261 * unregister_netdevice(y2); 10262 * ... 10263 * rtnl_unlock(); 10264 * free_netdev(y1); 10265 * free_netdev(y2); 10266 * 10267 * We are invoked by rtnl_unlock(). 10268 * This allows us to deal with problems: 10269 * 1) We can delete sysfs objects which invoke hotplug 10270 * without deadlocking with linkwatch via keventd. 10271 * 2) Since we run with the RTNL semaphore not held, we can sleep 10272 * safely in order to wait for the netdev refcnt to drop to zero. 10273 * 10274 * We must not return until all unregister events added during 10275 * the interval the lock was held have been completed. 10276 */ 10277 void netdev_run_todo(void) 10278 { 10279 struct net_device *dev, *tmp; 10280 struct list_head list; 10281 #ifdef CONFIG_LOCKDEP 10282 struct list_head unlink_list; 10283 10284 list_replace_init(&net_unlink_list, &unlink_list); 10285 10286 while (!list_empty(&unlink_list)) { 10287 struct net_device *dev = list_first_entry(&unlink_list, 10288 struct net_device, 10289 unlink_list); 10290 list_del_init(&dev->unlink_list); 10291 dev->nested_level = dev->lower_level - 1; 10292 } 10293 #endif 10294 10295 /* Snapshot list, allow later requests */ 10296 list_replace_init(&net_todo_list, &list); 10297 10298 __rtnl_unlock(); 10299 10300 /* Wait for rcu callbacks to finish before next phase */ 10301 if (!list_empty(&list)) 10302 rcu_barrier(); 10303 10304 list_for_each_entry_safe(dev, tmp, &list, todo_list) { 10305 if (unlikely(dev->reg_state != NETREG_UNREGISTERING)) { 10306 netdev_WARN(dev, "run_todo but not unregistering\n"); 10307 list_del(&dev->todo_list); 10308 continue; 10309 } 10310 10311 write_lock(&dev_base_lock); 10312 dev->reg_state = NETREG_UNREGISTERED; 10313 write_unlock(&dev_base_lock); 10314 linkwatch_forget_dev(dev); 10315 } 10316 10317 while (!list_empty(&list)) { 10318 dev = netdev_wait_allrefs_any(&list); 10319 list_del(&dev->todo_list); 10320 10321 /* paranoia */ 10322 BUG_ON(netdev_refcnt_read(dev) != 1); 10323 BUG_ON(!list_empty(&dev->ptype_all)); 10324 BUG_ON(!list_empty(&dev->ptype_specific)); 10325 WARN_ON(rcu_access_pointer(dev->ip_ptr)); 10326 WARN_ON(rcu_access_pointer(dev->ip6_ptr)); 10327 10328 if (dev->priv_destructor) 10329 dev->priv_destructor(dev); 10330 if (dev->needs_free_netdev) 10331 free_netdev(dev); 10332 10333 if (atomic_dec_and_test(&dev_net(dev)->dev_unreg_count)) 10334 wake_up(&netdev_unregistering_wq); 10335 10336 /* Free network device */ 10337 kobject_put(&dev->dev.kobj); 10338 } 10339 } 10340 10341 /* Convert net_device_stats to rtnl_link_stats64. rtnl_link_stats64 has 10342 * all the same fields in the same order as net_device_stats, with only 10343 * the type differing, but rtnl_link_stats64 may have additional fields 10344 * at the end for newer counters. 10345 */ 10346 void netdev_stats_to_stats64(struct rtnl_link_stats64 *stats64, 10347 const struct net_device_stats *netdev_stats) 10348 { 10349 size_t i, n = sizeof(*netdev_stats) / sizeof(atomic_long_t); 10350 const atomic_long_t *src = (atomic_long_t *)netdev_stats; 10351 u64 *dst = (u64 *)stats64; 10352 10353 BUILD_BUG_ON(n > sizeof(*stats64) / sizeof(u64)); 10354 for (i = 0; i < n; i++) 10355 dst[i] = (unsigned long)atomic_long_read(&src[i]); 10356 /* zero out counters that only exist in rtnl_link_stats64 */ 10357 memset((char *)stats64 + n * sizeof(u64), 0, 10358 sizeof(*stats64) - n * sizeof(u64)); 10359 } 10360 EXPORT_SYMBOL(netdev_stats_to_stats64); 10361 10362 struct net_device_core_stats __percpu *netdev_core_stats_alloc(struct net_device *dev) 10363 { 10364 struct net_device_core_stats __percpu *p; 10365 10366 p = alloc_percpu_gfp(struct net_device_core_stats, 10367 GFP_ATOMIC | __GFP_NOWARN); 10368 10369 if (p && cmpxchg(&dev->core_stats, NULL, p)) 10370 free_percpu(p); 10371 10372 /* This READ_ONCE() pairs with the cmpxchg() above */ 10373 return READ_ONCE(dev->core_stats); 10374 } 10375 EXPORT_SYMBOL(netdev_core_stats_alloc); 10376 10377 /** 10378 * dev_get_stats - get network device statistics 10379 * @dev: device to get statistics from 10380 * @storage: place to store stats 10381 * 10382 * Get network statistics from device. Return @storage. 10383 * The device driver may provide its own method by setting 10384 * dev->netdev_ops->get_stats64 or dev->netdev_ops->get_stats; 10385 * otherwise the internal statistics structure is used. 10386 */ 10387 struct rtnl_link_stats64 *dev_get_stats(struct net_device *dev, 10388 struct rtnl_link_stats64 *storage) 10389 { 10390 const struct net_device_ops *ops = dev->netdev_ops; 10391 const struct net_device_core_stats __percpu *p; 10392 10393 if (ops->ndo_get_stats64) { 10394 memset(storage, 0, sizeof(*storage)); 10395 ops->ndo_get_stats64(dev, storage); 10396 } else if (ops->ndo_get_stats) { 10397 netdev_stats_to_stats64(storage, ops->ndo_get_stats(dev)); 10398 } else { 10399 netdev_stats_to_stats64(storage, &dev->stats); 10400 } 10401 10402 /* This READ_ONCE() pairs with the write in netdev_core_stats_alloc() */ 10403 p = READ_ONCE(dev->core_stats); 10404 if (p) { 10405 const struct net_device_core_stats *core_stats; 10406 int i; 10407 10408 for_each_possible_cpu(i) { 10409 core_stats = per_cpu_ptr(p, i); 10410 storage->rx_dropped += READ_ONCE(core_stats->rx_dropped); 10411 storage->tx_dropped += READ_ONCE(core_stats->tx_dropped); 10412 storage->rx_nohandler += READ_ONCE(core_stats->rx_nohandler); 10413 storage->rx_otherhost_dropped += READ_ONCE(core_stats->rx_otherhost_dropped); 10414 } 10415 } 10416 return storage; 10417 } 10418 EXPORT_SYMBOL(dev_get_stats); 10419 10420 /** 10421 * dev_fetch_sw_netstats - get per-cpu network device statistics 10422 * @s: place to store stats 10423 * @netstats: per-cpu network stats to read from 10424 * 10425 * Read per-cpu network statistics and populate the related fields in @s. 10426 */ 10427 void dev_fetch_sw_netstats(struct rtnl_link_stats64 *s, 10428 const struct pcpu_sw_netstats __percpu *netstats) 10429 { 10430 int cpu; 10431 10432 for_each_possible_cpu(cpu) { 10433 u64 rx_packets, rx_bytes, tx_packets, tx_bytes; 10434 const struct pcpu_sw_netstats *stats; 10435 unsigned int start; 10436 10437 stats = per_cpu_ptr(netstats, cpu); 10438 do { 10439 start = u64_stats_fetch_begin(&stats->syncp); 10440 rx_packets = u64_stats_read(&stats->rx_packets); 10441 rx_bytes = u64_stats_read(&stats->rx_bytes); 10442 tx_packets = u64_stats_read(&stats->tx_packets); 10443 tx_bytes = u64_stats_read(&stats->tx_bytes); 10444 } while (u64_stats_fetch_retry(&stats->syncp, start)); 10445 10446 s->rx_packets += rx_packets; 10447 s->rx_bytes += rx_bytes; 10448 s->tx_packets += tx_packets; 10449 s->tx_bytes += tx_bytes; 10450 } 10451 } 10452 EXPORT_SYMBOL_GPL(dev_fetch_sw_netstats); 10453 10454 /** 10455 * dev_get_tstats64 - ndo_get_stats64 implementation 10456 * @dev: device to get statistics from 10457 * @s: place to store stats 10458 * 10459 * Populate @s from dev->stats and dev->tstats. Can be used as 10460 * ndo_get_stats64() callback. 10461 */ 10462 void dev_get_tstats64(struct net_device *dev, struct rtnl_link_stats64 *s) 10463 { 10464 netdev_stats_to_stats64(s, &dev->stats); 10465 dev_fetch_sw_netstats(s, dev->tstats); 10466 } 10467 EXPORT_SYMBOL_GPL(dev_get_tstats64); 10468 10469 struct netdev_queue *dev_ingress_queue_create(struct net_device *dev) 10470 { 10471 struct netdev_queue *queue = dev_ingress_queue(dev); 10472 10473 #ifdef CONFIG_NET_CLS_ACT 10474 if (queue) 10475 return queue; 10476 queue = kzalloc(sizeof(*queue), GFP_KERNEL); 10477 if (!queue) 10478 return NULL; 10479 netdev_init_one_queue(dev, queue, NULL); 10480 RCU_INIT_POINTER(queue->qdisc, &noop_qdisc); 10481 RCU_INIT_POINTER(queue->qdisc_sleeping, &noop_qdisc); 10482 rcu_assign_pointer(dev->ingress_queue, queue); 10483 #endif 10484 return queue; 10485 } 10486 10487 static const struct ethtool_ops default_ethtool_ops; 10488 10489 void netdev_set_default_ethtool_ops(struct net_device *dev, 10490 const struct ethtool_ops *ops) 10491 { 10492 if (dev->ethtool_ops == &default_ethtool_ops) 10493 dev->ethtool_ops = ops; 10494 } 10495 EXPORT_SYMBOL_GPL(netdev_set_default_ethtool_ops); 10496 10497 /** 10498 * netdev_sw_irq_coalesce_default_on() - enable SW IRQ coalescing by default 10499 * @dev: netdev to enable the IRQ coalescing on 10500 * 10501 * Sets a conservative default for SW IRQ coalescing. Users can use 10502 * sysfs attributes to override the default values. 10503 */ 10504 void netdev_sw_irq_coalesce_default_on(struct net_device *dev) 10505 { 10506 WARN_ON(dev->reg_state == NETREG_REGISTERED); 10507 10508 if (!IS_ENABLED(CONFIG_PREEMPT_RT)) { 10509 dev->gro_flush_timeout = 20000; 10510 dev->napi_defer_hard_irqs = 1; 10511 } 10512 } 10513 EXPORT_SYMBOL_GPL(netdev_sw_irq_coalesce_default_on); 10514 10515 void netdev_freemem(struct net_device *dev) 10516 { 10517 char *addr = (char *)dev - dev->padded; 10518 10519 kvfree(addr); 10520 } 10521 10522 /** 10523 * alloc_netdev_mqs - allocate network device 10524 * @sizeof_priv: size of private data to allocate space for 10525 * @name: device name format string 10526 * @name_assign_type: origin of device name 10527 * @setup: callback to initialize device 10528 * @txqs: the number of TX subqueues to allocate 10529 * @rxqs: the number of RX subqueues to allocate 10530 * 10531 * Allocates a struct net_device with private data area for driver use 10532 * and performs basic initialization. Also allocates subqueue structs 10533 * for each queue on the device. 10534 */ 10535 struct net_device *alloc_netdev_mqs(int sizeof_priv, const char *name, 10536 unsigned char name_assign_type, 10537 void (*setup)(struct net_device *), 10538 unsigned int txqs, unsigned int rxqs) 10539 { 10540 struct net_device *dev; 10541 unsigned int alloc_size; 10542 struct net_device *p; 10543 10544 BUG_ON(strlen(name) >= sizeof(dev->name)); 10545 10546 if (txqs < 1) { 10547 pr_err("alloc_netdev: Unable to allocate device with zero queues\n"); 10548 return NULL; 10549 } 10550 10551 if (rxqs < 1) { 10552 pr_err("alloc_netdev: Unable to allocate device with zero RX queues\n"); 10553 return NULL; 10554 } 10555 10556 alloc_size = sizeof(struct net_device); 10557 if (sizeof_priv) { 10558 /* ensure 32-byte alignment of private area */ 10559 alloc_size = ALIGN(alloc_size, NETDEV_ALIGN); 10560 alloc_size += sizeof_priv; 10561 } 10562 /* ensure 32-byte alignment of whole construct */ 10563 alloc_size += NETDEV_ALIGN - 1; 10564 10565 p = kvzalloc(alloc_size, GFP_KERNEL_ACCOUNT | __GFP_RETRY_MAYFAIL); 10566 if (!p) 10567 return NULL; 10568 10569 dev = PTR_ALIGN(p, NETDEV_ALIGN); 10570 dev->padded = (char *)dev - (char *)p; 10571 10572 ref_tracker_dir_init(&dev->refcnt_tracker, 128, name); 10573 #ifdef CONFIG_PCPU_DEV_REFCNT 10574 dev->pcpu_refcnt = alloc_percpu(int); 10575 if (!dev->pcpu_refcnt) 10576 goto free_dev; 10577 __dev_hold(dev); 10578 #else 10579 refcount_set(&dev->dev_refcnt, 1); 10580 #endif 10581 10582 if (dev_addr_init(dev)) 10583 goto free_pcpu; 10584 10585 dev_mc_init(dev); 10586 dev_uc_init(dev); 10587 10588 dev_net_set(dev, &init_net); 10589 10590 dev->gso_max_size = GSO_LEGACY_MAX_SIZE; 10591 dev->gso_max_segs = GSO_MAX_SEGS; 10592 dev->gro_max_size = GRO_LEGACY_MAX_SIZE; 10593 dev->gso_ipv4_max_size = GSO_LEGACY_MAX_SIZE; 10594 dev->gro_ipv4_max_size = GRO_LEGACY_MAX_SIZE; 10595 dev->tso_max_size = TSO_LEGACY_MAX_SIZE; 10596 dev->tso_max_segs = TSO_MAX_SEGS; 10597 dev->upper_level = 1; 10598 dev->lower_level = 1; 10599 #ifdef CONFIG_LOCKDEP 10600 dev->nested_level = 0; 10601 INIT_LIST_HEAD(&dev->unlink_list); 10602 #endif 10603 10604 INIT_LIST_HEAD(&dev->napi_list); 10605 INIT_LIST_HEAD(&dev->unreg_list); 10606 INIT_LIST_HEAD(&dev->close_list); 10607 INIT_LIST_HEAD(&dev->link_watch_list); 10608 INIT_LIST_HEAD(&dev->adj_list.upper); 10609 INIT_LIST_HEAD(&dev->adj_list.lower); 10610 INIT_LIST_HEAD(&dev->ptype_all); 10611 INIT_LIST_HEAD(&dev->ptype_specific); 10612 INIT_LIST_HEAD(&dev->net_notifier_list); 10613 #ifdef CONFIG_NET_SCHED 10614 hash_init(dev->qdisc_hash); 10615 #endif 10616 dev->priv_flags = IFF_XMIT_DST_RELEASE | IFF_XMIT_DST_RELEASE_PERM; 10617 setup(dev); 10618 10619 if (!dev->tx_queue_len) { 10620 dev->priv_flags |= IFF_NO_QUEUE; 10621 dev->tx_queue_len = DEFAULT_TX_QUEUE_LEN; 10622 } 10623 10624 dev->num_tx_queues = txqs; 10625 dev->real_num_tx_queues = txqs; 10626 if (netif_alloc_netdev_queues(dev)) 10627 goto free_all; 10628 10629 dev->num_rx_queues = rxqs; 10630 dev->real_num_rx_queues = rxqs; 10631 if (netif_alloc_rx_queues(dev)) 10632 goto free_all; 10633 10634 strcpy(dev->name, name); 10635 dev->name_assign_type = name_assign_type; 10636 dev->group = INIT_NETDEV_GROUP; 10637 if (!dev->ethtool_ops) 10638 dev->ethtool_ops = &default_ethtool_ops; 10639 10640 nf_hook_netdev_init(dev); 10641 10642 return dev; 10643 10644 free_all: 10645 free_netdev(dev); 10646 return NULL; 10647 10648 free_pcpu: 10649 #ifdef CONFIG_PCPU_DEV_REFCNT 10650 free_percpu(dev->pcpu_refcnt); 10651 free_dev: 10652 #endif 10653 netdev_freemem(dev); 10654 return NULL; 10655 } 10656 EXPORT_SYMBOL(alloc_netdev_mqs); 10657 10658 /** 10659 * free_netdev - free network device 10660 * @dev: device 10661 * 10662 * This function does the last stage of destroying an allocated device 10663 * interface. The reference to the device object is released. If this 10664 * is the last reference then it will be freed.Must be called in process 10665 * context. 10666 */ 10667 void free_netdev(struct net_device *dev) 10668 { 10669 struct napi_struct *p, *n; 10670 10671 might_sleep(); 10672 10673 /* When called immediately after register_netdevice() failed the unwind 10674 * handling may still be dismantling the device. Handle that case by 10675 * deferring the free. 10676 */ 10677 if (dev->reg_state == NETREG_UNREGISTERING) { 10678 ASSERT_RTNL(); 10679 dev->needs_free_netdev = true; 10680 return; 10681 } 10682 10683 netif_free_tx_queues(dev); 10684 netif_free_rx_queues(dev); 10685 10686 kfree(rcu_dereference_protected(dev->ingress_queue, 1)); 10687 10688 /* Flush device addresses */ 10689 dev_addr_flush(dev); 10690 10691 list_for_each_entry_safe(p, n, &dev->napi_list, dev_list) 10692 netif_napi_del(p); 10693 10694 ref_tracker_dir_exit(&dev->refcnt_tracker); 10695 #ifdef CONFIG_PCPU_DEV_REFCNT 10696 free_percpu(dev->pcpu_refcnt); 10697 dev->pcpu_refcnt = NULL; 10698 #endif 10699 free_percpu(dev->core_stats); 10700 dev->core_stats = NULL; 10701 free_percpu(dev->xdp_bulkq); 10702 dev->xdp_bulkq = NULL; 10703 10704 /* Compatibility with error handling in drivers */ 10705 if (dev->reg_state == NETREG_UNINITIALIZED) { 10706 netdev_freemem(dev); 10707 return; 10708 } 10709 10710 BUG_ON(dev->reg_state != NETREG_UNREGISTERED); 10711 dev->reg_state = NETREG_RELEASED; 10712 10713 /* will free via device release */ 10714 put_device(&dev->dev); 10715 } 10716 EXPORT_SYMBOL(free_netdev); 10717 10718 /** 10719 * synchronize_net - Synchronize with packet receive processing 10720 * 10721 * Wait for packets currently being received to be done. 10722 * Does not block later packets from starting. 10723 */ 10724 void synchronize_net(void) 10725 { 10726 might_sleep(); 10727 if (rtnl_is_locked()) 10728 synchronize_rcu_expedited(); 10729 else 10730 synchronize_rcu(); 10731 } 10732 EXPORT_SYMBOL(synchronize_net); 10733 10734 /** 10735 * unregister_netdevice_queue - remove device from the kernel 10736 * @dev: device 10737 * @head: list 10738 * 10739 * This function shuts down a device interface and removes it 10740 * from the kernel tables. 10741 * If head not NULL, device is queued to be unregistered later. 10742 * 10743 * Callers must hold the rtnl semaphore. You may want 10744 * unregister_netdev() instead of this. 10745 */ 10746 10747 void unregister_netdevice_queue(struct net_device *dev, struct list_head *head) 10748 { 10749 ASSERT_RTNL(); 10750 10751 if (head) { 10752 list_move_tail(&dev->unreg_list, head); 10753 } else { 10754 LIST_HEAD(single); 10755 10756 list_add(&dev->unreg_list, &single); 10757 unregister_netdevice_many(&single); 10758 } 10759 } 10760 EXPORT_SYMBOL(unregister_netdevice_queue); 10761 10762 void unregister_netdevice_many_notify(struct list_head *head, 10763 u32 portid, const struct nlmsghdr *nlh) 10764 { 10765 struct net_device *dev, *tmp; 10766 LIST_HEAD(close_head); 10767 10768 BUG_ON(dev_boot_phase); 10769 ASSERT_RTNL(); 10770 10771 if (list_empty(head)) 10772 return; 10773 10774 list_for_each_entry_safe(dev, tmp, head, unreg_list) { 10775 /* Some devices call without registering 10776 * for initialization unwind. Remove those 10777 * devices and proceed with the remaining. 10778 */ 10779 if (dev->reg_state == NETREG_UNINITIALIZED) { 10780 pr_debug("unregister_netdevice: device %s/%p never was registered\n", 10781 dev->name, dev); 10782 10783 WARN_ON(1); 10784 list_del(&dev->unreg_list); 10785 continue; 10786 } 10787 dev->dismantle = true; 10788 BUG_ON(dev->reg_state != NETREG_REGISTERED); 10789 } 10790 10791 /* If device is running, close it first. */ 10792 list_for_each_entry(dev, head, unreg_list) 10793 list_add_tail(&dev->close_list, &close_head); 10794 dev_close_many(&close_head, true); 10795 10796 list_for_each_entry(dev, head, unreg_list) { 10797 /* And unlink it from device chain. */ 10798 write_lock(&dev_base_lock); 10799 unlist_netdevice(dev, false); 10800 dev->reg_state = NETREG_UNREGISTERING; 10801 write_unlock(&dev_base_lock); 10802 } 10803 flush_all_backlogs(); 10804 10805 synchronize_net(); 10806 10807 list_for_each_entry(dev, head, unreg_list) { 10808 struct sk_buff *skb = NULL; 10809 10810 /* Shutdown queueing discipline. */ 10811 dev_shutdown(dev); 10812 10813 dev_xdp_uninstall(dev); 10814 bpf_dev_bound_netdev_unregister(dev); 10815 10816 netdev_offload_xstats_disable_all(dev); 10817 10818 /* Notify protocols, that we are about to destroy 10819 * this device. They should clean all the things. 10820 */ 10821 call_netdevice_notifiers(NETDEV_UNREGISTER, dev); 10822 10823 if (!dev->rtnl_link_ops || 10824 dev->rtnl_link_state == RTNL_LINK_INITIALIZED) 10825 skb = rtmsg_ifinfo_build_skb(RTM_DELLINK, dev, ~0U, 0, 10826 GFP_KERNEL, NULL, 0, 10827 portid, nlh); 10828 10829 /* 10830 * Flush the unicast and multicast chains 10831 */ 10832 dev_uc_flush(dev); 10833 dev_mc_flush(dev); 10834 10835 netdev_name_node_alt_flush(dev); 10836 netdev_name_node_free(dev->name_node); 10837 10838 call_netdevice_notifiers(NETDEV_PRE_UNINIT, dev); 10839 10840 if (dev->netdev_ops->ndo_uninit) 10841 dev->netdev_ops->ndo_uninit(dev); 10842 10843 if (skb) 10844 rtmsg_ifinfo_send(skb, dev, GFP_KERNEL, portid, nlh); 10845 10846 /* Notifier chain MUST detach us all upper devices. */ 10847 WARN_ON(netdev_has_any_upper_dev(dev)); 10848 WARN_ON(netdev_has_any_lower_dev(dev)); 10849 10850 /* Remove entries from kobject tree */ 10851 netdev_unregister_kobject(dev); 10852 #ifdef CONFIG_XPS 10853 /* Remove XPS queueing entries */ 10854 netif_reset_xps_queues_gt(dev, 0); 10855 #endif 10856 } 10857 10858 synchronize_net(); 10859 10860 list_for_each_entry(dev, head, unreg_list) { 10861 netdev_put(dev, &dev->dev_registered_tracker); 10862 net_set_todo(dev); 10863 } 10864 10865 list_del(head); 10866 } 10867 10868 /** 10869 * unregister_netdevice_many - unregister many devices 10870 * @head: list of devices 10871 * 10872 * Note: As most callers use a stack allocated list_head, 10873 * we force a list_del() to make sure stack wont be corrupted later. 10874 */ 10875 void unregister_netdevice_many(struct list_head *head) 10876 { 10877 unregister_netdevice_many_notify(head, 0, NULL); 10878 } 10879 EXPORT_SYMBOL(unregister_netdevice_many); 10880 10881 /** 10882 * unregister_netdev - remove device from the kernel 10883 * @dev: device 10884 * 10885 * This function shuts down a device interface and removes it 10886 * from the kernel tables. 10887 * 10888 * This is just a wrapper for unregister_netdevice that takes 10889 * the rtnl semaphore. In general you want to use this and not 10890 * unregister_netdevice. 10891 */ 10892 void unregister_netdev(struct net_device *dev) 10893 { 10894 rtnl_lock(); 10895 unregister_netdevice(dev); 10896 rtnl_unlock(); 10897 } 10898 EXPORT_SYMBOL(unregister_netdev); 10899 10900 /** 10901 * __dev_change_net_namespace - move device to different nethost namespace 10902 * @dev: device 10903 * @net: network namespace 10904 * @pat: If not NULL name pattern to try if the current device name 10905 * is already taken in the destination network namespace. 10906 * @new_ifindex: If not zero, specifies device index in the target 10907 * namespace. 10908 * 10909 * This function shuts down a device interface and moves it 10910 * to a new network namespace. On success 0 is returned, on 10911 * a failure a netagive errno code is returned. 10912 * 10913 * Callers must hold the rtnl semaphore. 10914 */ 10915 10916 int __dev_change_net_namespace(struct net_device *dev, struct net *net, 10917 const char *pat, int new_ifindex) 10918 { 10919 struct net *net_old = dev_net(dev); 10920 int err, new_nsid; 10921 10922 ASSERT_RTNL(); 10923 10924 /* Don't allow namespace local devices to be moved. */ 10925 err = -EINVAL; 10926 if (dev->features & NETIF_F_NETNS_LOCAL) 10927 goto out; 10928 10929 /* Ensure the device has been registrered */ 10930 if (dev->reg_state != NETREG_REGISTERED) 10931 goto out; 10932 10933 /* Get out if there is nothing todo */ 10934 err = 0; 10935 if (net_eq(net_old, net)) 10936 goto out; 10937 10938 /* Pick the destination device name, and ensure 10939 * we can use it in the destination network namespace. 10940 */ 10941 err = -EEXIST; 10942 if (netdev_name_in_use(net, dev->name)) { 10943 /* We get here if we can't use the current device name */ 10944 if (!pat) 10945 goto out; 10946 err = dev_get_valid_name(net, dev, pat); 10947 if (err < 0) 10948 goto out; 10949 } 10950 10951 /* Check that new_ifindex isn't used yet. */ 10952 err = -EBUSY; 10953 if (new_ifindex && __dev_get_by_index(net, new_ifindex)) 10954 goto out; 10955 10956 /* 10957 * And now a mini version of register_netdevice unregister_netdevice. 10958 */ 10959 10960 /* If device is running close it first. */ 10961 dev_close(dev); 10962 10963 /* And unlink it from device chain */ 10964 unlist_netdevice(dev, true); 10965 10966 synchronize_net(); 10967 10968 /* Shutdown queueing discipline. */ 10969 dev_shutdown(dev); 10970 10971 /* Notify protocols, that we are about to destroy 10972 * this device. They should clean all the things. 10973 * 10974 * Note that dev->reg_state stays at NETREG_REGISTERED. 10975 * This is wanted because this way 8021q and macvlan know 10976 * the device is just moving and can keep their slaves up. 10977 */ 10978 call_netdevice_notifiers(NETDEV_UNREGISTER, dev); 10979 rcu_barrier(); 10980 10981 new_nsid = peernet2id_alloc(dev_net(dev), net, GFP_KERNEL); 10982 /* If there is an ifindex conflict assign a new one */ 10983 if (!new_ifindex) { 10984 if (__dev_get_by_index(net, dev->ifindex)) 10985 new_ifindex = dev_new_index(net); 10986 else 10987 new_ifindex = dev->ifindex; 10988 } 10989 10990 rtmsg_ifinfo_newnet(RTM_DELLINK, dev, ~0U, GFP_KERNEL, &new_nsid, 10991 new_ifindex); 10992 10993 /* 10994 * Flush the unicast and multicast chains 10995 */ 10996 dev_uc_flush(dev); 10997 dev_mc_flush(dev); 10998 10999 /* Send a netdev-removed uevent to the old namespace */ 11000 kobject_uevent(&dev->dev.kobj, KOBJ_REMOVE); 11001 netdev_adjacent_del_links(dev); 11002 11003 /* Move per-net netdevice notifiers that are following the netdevice */ 11004 move_netdevice_notifiers_dev_net(dev, net); 11005 11006 /* Actually switch the network namespace */ 11007 dev_net_set(dev, net); 11008 dev->ifindex = new_ifindex; 11009 11010 /* Send a netdev-add uevent to the new namespace */ 11011 kobject_uevent(&dev->dev.kobj, KOBJ_ADD); 11012 netdev_adjacent_add_links(dev); 11013 11014 /* Fixup kobjects */ 11015 err = device_rename(&dev->dev, dev->name); 11016 WARN_ON(err); 11017 11018 /* Adapt owner in case owning user namespace of target network 11019 * namespace is different from the original one. 11020 */ 11021 err = netdev_change_owner(dev, net_old, net); 11022 WARN_ON(err); 11023 11024 /* Add the device back in the hashes */ 11025 list_netdevice(dev); 11026 11027 /* Notify protocols, that a new device appeared. */ 11028 call_netdevice_notifiers(NETDEV_REGISTER, dev); 11029 11030 /* 11031 * Prevent userspace races by waiting until the network 11032 * device is fully setup before sending notifications. 11033 */ 11034 rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U, GFP_KERNEL, 0, NULL); 11035 11036 synchronize_net(); 11037 err = 0; 11038 out: 11039 return err; 11040 } 11041 EXPORT_SYMBOL_GPL(__dev_change_net_namespace); 11042 11043 static int dev_cpu_dead(unsigned int oldcpu) 11044 { 11045 struct sk_buff **list_skb; 11046 struct sk_buff *skb; 11047 unsigned int cpu; 11048 struct softnet_data *sd, *oldsd, *remsd = NULL; 11049 11050 local_irq_disable(); 11051 cpu = smp_processor_id(); 11052 sd = &per_cpu(softnet_data, cpu); 11053 oldsd = &per_cpu(softnet_data, oldcpu); 11054 11055 /* Find end of our completion_queue. */ 11056 list_skb = &sd->completion_queue; 11057 while (*list_skb) 11058 list_skb = &(*list_skb)->next; 11059 /* Append completion queue from offline CPU. */ 11060 *list_skb = oldsd->completion_queue; 11061 oldsd->completion_queue = NULL; 11062 11063 /* Append output queue from offline CPU. */ 11064 if (oldsd->output_queue) { 11065 *sd->output_queue_tailp = oldsd->output_queue; 11066 sd->output_queue_tailp = oldsd->output_queue_tailp; 11067 oldsd->output_queue = NULL; 11068 oldsd->output_queue_tailp = &oldsd->output_queue; 11069 } 11070 /* Append NAPI poll list from offline CPU, with one exception : 11071 * process_backlog() must be called by cpu owning percpu backlog. 11072 * We properly handle process_queue & input_pkt_queue later. 11073 */ 11074 while (!list_empty(&oldsd->poll_list)) { 11075 struct napi_struct *napi = list_first_entry(&oldsd->poll_list, 11076 struct napi_struct, 11077 poll_list); 11078 11079 list_del_init(&napi->poll_list); 11080 if (napi->poll == process_backlog) 11081 napi->state = 0; 11082 else 11083 ____napi_schedule(sd, napi); 11084 } 11085 11086 raise_softirq_irqoff(NET_TX_SOFTIRQ); 11087 local_irq_enable(); 11088 11089 #ifdef CONFIG_RPS 11090 remsd = oldsd->rps_ipi_list; 11091 oldsd->rps_ipi_list = NULL; 11092 #endif 11093 /* send out pending IPI's on offline CPU */ 11094 net_rps_send_ipi(remsd); 11095 11096 /* Process offline CPU's input_pkt_queue */ 11097 while ((skb = __skb_dequeue(&oldsd->process_queue))) { 11098 netif_rx(skb); 11099 input_queue_head_incr(oldsd); 11100 } 11101 while ((skb = skb_dequeue(&oldsd->input_pkt_queue))) { 11102 netif_rx(skb); 11103 input_queue_head_incr(oldsd); 11104 } 11105 11106 return 0; 11107 } 11108 11109 /** 11110 * netdev_increment_features - increment feature set by one 11111 * @all: current feature set 11112 * @one: new feature set 11113 * @mask: mask feature set 11114 * 11115 * Computes a new feature set after adding a device with feature set 11116 * @one to the master device with current feature set @all. Will not 11117 * enable anything that is off in @mask. Returns the new feature set. 11118 */ 11119 netdev_features_t netdev_increment_features(netdev_features_t all, 11120 netdev_features_t one, netdev_features_t mask) 11121 { 11122 if (mask & NETIF_F_HW_CSUM) 11123 mask |= NETIF_F_CSUM_MASK; 11124 mask |= NETIF_F_VLAN_CHALLENGED; 11125 11126 all |= one & (NETIF_F_ONE_FOR_ALL | NETIF_F_CSUM_MASK) & mask; 11127 all &= one | ~NETIF_F_ALL_FOR_ALL; 11128 11129 /* If one device supports hw checksumming, set for all. */ 11130 if (all & NETIF_F_HW_CSUM) 11131 all &= ~(NETIF_F_CSUM_MASK & ~NETIF_F_HW_CSUM); 11132 11133 return all; 11134 } 11135 EXPORT_SYMBOL(netdev_increment_features); 11136 11137 static struct hlist_head * __net_init netdev_create_hash(void) 11138 { 11139 int i; 11140 struct hlist_head *hash; 11141 11142 hash = kmalloc_array(NETDEV_HASHENTRIES, sizeof(*hash), GFP_KERNEL); 11143 if (hash != NULL) 11144 for (i = 0; i < NETDEV_HASHENTRIES; i++) 11145 INIT_HLIST_HEAD(&hash[i]); 11146 11147 return hash; 11148 } 11149 11150 /* Initialize per network namespace state */ 11151 static int __net_init netdev_init(struct net *net) 11152 { 11153 BUILD_BUG_ON(GRO_HASH_BUCKETS > 11154 8 * sizeof_field(struct napi_struct, gro_bitmask)); 11155 11156 INIT_LIST_HEAD(&net->dev_base_head); 11157 11158 net->dev_name_head = netdev_create_hash(); 11159 if (net->dev_name_head == NULL) 11160 goto err_name; 11161 11162 net->dev_index_head = netdev_create_hash(); 11163 if (net->dev_index_head == NULL) 11164 goto err_idx; 11165 11166 RAW_INIT_NOTIFIER_HEAD(&net->netdev_chain); 11167 11168 return 0; 11169 11170 err_idx: 11171 kfree(net->dev_name_head); 11172 err_name: 11173 return -ENOMEM; 11174 } 11175 11176 /** 11177 * netdev_drivername - network driver for the device 11178 * @dev: network device 11179 * 11180 * Determine network driver for device. 11181 */ 11182 const char *netdev_drivername(const struct net_device *dev) 11183 { 11184 const struct device_driver *driver; 11185 const struct device *parent; 11186 const char *empty = ""; 11187 11188 parent = dev->dev.parent; 11189 if (!parent) 11190 return empty; 11191 11192 driver = parent->driver; 11193 if (driver && driver->name) 11194 return driver->name; 11195 return empty; 11196 } 11197 11198 static void __netdev_printk(const char *level, const struct net_device *dev, 11199 struct va_format *vaf) 11200 { 11201 if (dev && dev->dev.parent) { 11202 dev_printk_emit(level[1] - '0', 11203 dev->dev.parent, 11204 "%s %s %s%s: %pV", 11205 dev_driver_string(dev->dev.parent), 11206 dev_name(dev->dev.parent), 11207 netdev_name(dev), netdev_reg_state(dev), 11208 vaf); 11209 } else if (dev) { 11210 printk("%s%s%s: %pV", 11211 level, netdev_name(dev), netdev_reg_state(dev), vaf); 11212 } else { 11213 printk("%s(NULL net_device): %pV", level, vaf); 11214 } 11215 } 11216 11217 void netdev_printk(const char *level, const struct net_device *dev, 11218 const char *format, ...) 11219 { 11220 struct va_format vaf; 11221 va_list args; 11222 11223 va_start(args, format); 11224 11225 vaf.fmt = format; 11226 vaf.va = &args; 11227 11228 __netdev_printk(level, dev, &vaf); 11229 11230 va_end(args); 11231 } 11232 EXPORT_SYMBOL(netdev_printk); 11233 11234 #define define_netdev_printk_level(func, level) \ 11235 void func(const struct net_device *dev, const char *fmt, ...) \ 11236 { \ 11237 struct va_format vaf; \ 11238 va_list args; \ 11239 \ 11240 va_start(args, fmt); \ 11241 \ 11242 vaf.fmt = fmt; \ 11243 vaf.va = &args; \ 11244 \ 11245 __netdev_printk(level, dev, &vaf); \ 11246 \ 11247 va_end(args); \ 11248 } \ 11249 EXPORT_SYMBOL(func); 11250 11251 define_netdev_printk_level(netdev_emerg, KERN_EMERG); 11252 define_netdev_printk_level(netdev_alert, KERN_ALERT); 11253 define_netdev_printk_level(netdev_crit, KERN_CRIT); 11254 define_netdev_printk_level(netdev_err, KERN_ERR); 11255 define_netdev_printk_level(netdev_warn, KERN_WARNING); 11256 define_netdev_printk_level(netdev_notice, KERN_NOTICE); 11257 define_netdev_printk_level(netdev_info, KERN_INFO); 11258 11259 static void __net_exit netdev_exit(struct net *net) 11260 { 11261 kfree(net->dev_name_head); 11262 kfree(net->dev_index_head); 11263 if (net != &init_net) 11264 WARN_ON_ONCE(!list_empty(&net->dev_base_head)); 11265 } 11266 11267 static struct pernet_operations __net_initdata netdev_net_ops = { 11268 .init = netdev_init, 11269 .exit = netdev_exit, 11270 }; 11271 11272 static void __net_exit default_device_exit_net(struct net *net) 11273 { 11274 struct net_device *dev, *aux; 11275 /* 11276 * Push all migratable network devices back to the 11277 * initial network namespace 11278 */ 11279 ASSERT_RTNL(); 11280 for_each_netdev_safe(net, dev, aux) { 11281 int err; 11282 char fb_name[IFNAMSIZ]; 11283 11284 /* Ignore unmoveable devices (i.e. loopback) */ 11285 if (dev->features & NETIF_F_NETNS_LOCAL) 11286 continue; 11287 11288 /* Leave virtual devices for the generic cleanup */ 11289 if (dev->rtnl_link_ops && !dev->rtnl_link_ops->netns_refund) 11290 continue; 11291 11292 /* Push remaining network devices to init_net */ 11293 snprintf(fb_name, IFNAMSIZ, "dev%d", dev->ifindex); 11294 if (netdev_name_in_use(&init_net, fb_name)) 11295 snprintf(fb_name, IFNAMSIZ, "dev%%d"); 11296 err = dev_change_net_namespace(dev, &init_net, fb_name); 11297 if (err) { 11298 pr_emerg("%s: failed to move %s to init_net: %d\n", 11299 __func__, dev->name, err); 11300 BUG(); 11301 } 11302 } 11303 } 11304 11305 static void __net_exit default_device_exit_batch(struct list_head *net_list) 11306 { 11307 /* At exit all network devices most be removed from a network 11308 * namespace. Do this in the reverse order of registration. 11309 * Do this across as many network namespaces as possible to 11310 * improve batching efficiency. 11311 */ 11312 struct net_device *dev; 11313 struct net *net; 11314 LIST_HEAD(dev_kill_list); 11315 11316 rtnl_lock(); 11317 list_for_each_entry(net, net_list, exit_list) { 11318 default_device_exit_net(net); 11319 cond_resched(); 11320 } 11321 11322 list_for_each_entry(net, net_list, exit_list) { 11323 for_each_netdev_reverse(net, dev) { 11324 if (dev->rtnl_link_ops && dev->rtnl_link_ops->dellink) 11325 dev->rtnl_link_ops->dellink(dev, &dev_kill_list); 11326 else 11327 unregister_netdevice_queue(dev, &dev_kill_list); 11328 } 11329 } 11330 unregister_netdevice_many(&dev_kill_list); 11331 rtnl_unlock(); 11332 } 11333 11334 static struct pernet_operations __net_initdata default_device_ops = { 11335 .exit_batch = default_device_exit_batch, 11336 }; 11337 11338 /* 11339 * Initialize the DEV module. At boot time this walks the device list and 11340 * unhooks any devices that fail to initialise (normally hardware not 11341 * present) and leaves us with a valid list of present and active devices. 11342 * 11343 */ 11344 11345 /* 11346 * This is called single threaded during boot, so no need 11347 * to take the rtnl semaphore. 11348 */ 11349 static int __init net_dev_init(void) 11350 { 11351 int i, rc = -ENOMEM; 11352 11353 BUG_ON(!dev_boot_phase); 11354 11355 if (dev_proc_init()) 11356 goto out; 11357 11358 if (netdev_kobject_init()) 11359 goto out; 11360 11361 INIT_LIST_HEAD(&ptype_all); 11362 for (i = 0; i < PTYPE_HASH_SIZE; i++) 11363 INIT_LIST_HEAD(&ptype_base[i]); 11364 11365 if (register_pernet_subsys(&netdev_net_ops)) 11366 goto out; 11367 11368 /* 11369 * Initialise the packet receive queues. 11370 */ 11371 11372 for_each_possible_cpu(i) { 11373 struct work_struct *flush = per_cpu_ptr(&flush_works, i); 11374 struct softnet_data *sd = &per_cpu(softnet_data, i); 11375 11376 INIT_WORK(flush, flush_backlog); 11377 11378 skb_queue_head_init(&sd->input_pkt_queue); 11379 skb_queue_head_init(&sd->process_queue); 11380 #ifdef CONFIG_XFRM_OFFLOAD 11381 skb_queue_head_init(&sd->xfrm_backlog); 11382 #endif 11383 INIT_LIST_HEAD(&sd->poll_list); 11384 sd->output_queue_tailp = &sd->output_queue; 11385 #ifdef CONFIG_RPS 11386 INIT_CSD(&sd->csd, rps_trigger_softirq, sd); 11387 sd->cpu = i; 11388 #endif 11389 INIT_CSD(&sd->defer_csd, trigger_rx_softirq, sd); 11390 spin_lock_init(&sd->defer_lock); 11391 11392 init_gro_hash(&sd->backlog); 11393 sd->backlog.poll = process_backlog; 11394 sd->backlog.weight = weight_p; 11395 } 11396 11397 dev_boot_phase = 0; 11398 11399 /* The loopback device is special if any other network devices 11400 * is present in a network namespace the loopback device must 11401 * be present. Since we now dynamically allocate and free the 11402 * loopback device ensure this invariant is maintained by 11403 * keeping the loopback device as the first device on the 11404 * list of network devices. Ensuring the loopback devices 11405 * is the first device that appears and the last network device 11406 * that disappears. 11407 */ 11408 if (register_pernet_device(&loopback_net_ops)) 11409 goto out; 11410 11411 if (register_pernet_device(&default_device_ops)) 11412 goto out; 11413 11414 open_softirq(NET_TX_SOFTIRQ, net_tx_action); 11415 open_softirq(NET_RX_SOFTIRQ, net_rx_action); 11416 11417 rc = cpuhp_setup_state_nocalls(CPUHP_NET_DEV_DEAD, "net/dev:dead", 11418 NULL, dev_cpu_dead); 11419 WARN_ON(rc < 0); 11420 rc = 0; 11421 out: 11422 return rc; 11423 } 11424 11425 subsys_initcall(net_dev_init); 11426