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_info(unsigned long val, 164 struct netdev_notifier_info *info); 165 static int call_netdevice_notifiers_extack(unsigned long val, 166 struct net_device *dev, 167 struct netlink_ext_ack *extack); 168 static struct napi_struct *napi_by_id(unsigned int napi_id); 169 170 /* 171 * The @dev_base_head list is protected by @dev_base_lock and the rtnl 172 * semaphore. 173 * 174 * Pure readers hold dev_base_lock for reading, or rcu_read_lock() 175 * 176 * Writers must hold the rtnl semaphore while they loop through the 177 * dev_base_head list, and hold dev_base_lock for writing when they do the 178 * actual updates. This allows pure readers to access the list even 179 * while a writer is preparing to update it. 180 * 181 * To put it another way, dev_base_lock is held for writing only to 182 * protect against pure readers; the rtnl semaphore provides the 183 * protection against other writers. 184 * 185 * See, for example usages, register_netdevice() and 186 * unregister_netdevice(), which must be called with the rtnl 187 * semaphore held. 188 */ 189 DEFINE_RWLOCK(dev_base_lock); 190 EXPORT_SYMBOL(dev_base_lock); 191 192 static DEFINE_MUTEX(ifalias_mutex); 193 194 /* protects napi_hash addition/deletion and napi_gen_id */ 195 static DEFINE_SPINLOCK(napi_hash_lock); 196 197 static unsigned int napi_gen_id = NR_CPUS; 198 static DEFINE_READ_MOSTLY_HASHTABLE(napi_hash, 8); 199 200 static DECLARE_RWSEM(devnet_rename_sem); 201 202 static inline void dev_base_seq_inc(struct net *net) 203 { 204 while (++net->dev_base_seq == 0) 205 ; 206 } 207 208 static inline struct hlist_head *dev_name_hash(struct net *net, const char *name) 209 { 210 unsigned int hash = full_name_hash(net, name, strnlen(name, IFNAMSIZ)); 211 212 return &net->dev_name_head[hash_32(hash, NETDEV_HASHBITS)]; 213 } 214 215 static inline struct hlist_head *dev_index_hash(struct net *net, int ifindex) 216 { 217 return &net->dev_index_head[ifindex & (NETDEV_HASHENTRIES - 1)]; 218 } 219 220 static inline void rps_lock_irqsave(struct softnet_data *sd, 221 unsigned long *flags) 222 { 223 if (IS_ENABLED(CONFIG_RPS)) 224 spin_lock_irqsave(&sd->input_pkt_queue.lock, *flags); 225 else if (!IS_ENABLED(CONFIG_PREEMPT_RT)) 226 local_irq_save(*flags); 227 } 228 229 static inline void rps_lock_irq_disable(struct softnet_data *sd) 230 { 231 if (IS_ENABLED(CONFIG_RPS)) 232 spin_lock_irq(&sd->input_pkt_queue.lock); 233 else if (!IS_ENABLED(CONFIG_PREEMPT_RT)) 234 local_irq_disable(); 235 } 236 237 static inline void rps_unlock_irq_restore(struct softnet_data *sd, 238 unsigned long *flags) 239 { 240 if (IS_ENABLED(CONFIG_RPS)) 241 spin_unlock_irqrestore(&sd->input_pkt_queue.lock, *flags); 242 else if (!IS_ENABLED(CONFIG_PREEMPT_RT)) 243 local_irq_restore(*flags); 244 } 245 246 static inline void rps_unlock_irq_enable(struct softnet_data *sd) 247 { 248 if (IS_ENABLED(CONFIG_RPS)) 249 spin_unlock_irq(&sd->input_pkt_queue.lock); 250 else if (!IS_ENABLED(CONFIG_PREEMPT_RT)) 251 local_irq_enable(); 252 } 253 254 static struct netdev_name_node *netdev_name_node_alloc(struct net_device *dev, 255 const char *name) 256 { 257 struct netdev_name_node *name_node; 258 259 name_node = kmalloc(sizeof(*name_node), GFP_KERNEL); 260 if (!name_node) 261 return NULL; 262 INIT_HLIST_NODE(&name_node->hlist); 263 name_node->dev = dev; 264 name_node->name = name; 265 return name_node; 266 } 267 268 static struct netdev_name_node * 269 netdev_name_node_head_alloc(struct net_device *dev) 270 { 271 struct netdev_name_node *name_node; 272 273 name_node = netdev_name_node_alloc(dev, dev->name); 274 if (!name_node) 275 return NULL; 276 INIT_LIST_HEAD(&name_node->list); 277 return name_node; 278 } 279 280 static void netdev_name_node_free(struct netdev_name_node *name_node) 281 { 282 kfree(name_node); 283 } 284 285 static void netdev_name_node_add(struct net *net, 286 struct netdev_name_node *name_node) 287 { 288 hlist_add_head_rcu(&name_node->hlist, 289 dev_name_hash(net, name_node->name)); 290 } 291 292 static void netdev_name_node_del(struct netdev_name_node *name_node) 293 { 294 hlist_del_rcu(&name_node->hlist); 295 } 296 297 static struct netdev_name_node *netdev_name_node_lookup(struct net *net, 298 const char *name) 299 { 300 struct hlist_head *head = dev_name_hash(net, name); 301 struct netdev_name_node *name_node; 302 303 hlist_for_each_entry(name_node, head, hlist) 304 if (!strcmp(name_node->name, name)) 305 return name_node; 306 return NULL; 307 } 308 309 static struct netdev_name_node *netdev_name_node_lookup_rcu(struct net *net, 310 const char *name) 311 { 312 struct hlist_head *head = dev_name_hash(net, name); 313 struct netdev_name_node *name_node; 314 315 hlist_for_each_entry_rcu(name_node, head, hlist) 316 if (!strcmp(name_node->name, name)) 317 return name_node; 318 return NULL; 319 } 320 321 bool netdev_name_in_use(struct net *net, const char *name) 322 { 323 return netdev_name_node_lookup(net, name); 324 } 325 EXPORT_SYMBOL(netdev_name_in_use); 326 327 int netdev_name_node_alt_create(struct net_device *dev, const char *name) 328 { 329 struct netdev_name_node *name_node; 330 struct net *net = dev_net(dev); 331 332 name_node = netdev_name_node_lookup(net, name); 333 if (name_node) 334 return -EEXIST; 335 name_node = netdev_name_node_alloc(dev, name); 336 if (!name_node) 337 return -ENOMEM; 338 netdev_name_node_add(net, name_node); 339 /* The node that holds dev->name acts as a head of per-device list. */ 340 list_add_tail(&name_node->list, &dev->name_node->list); 341 342 return 0; 343 } 344 345 static void __netdev_name_node_alt_destroy(struct netdev_name_node *name_node) 346 { 347 list_del(&name_node->list); 348 netdev_name_node_del(name_node); 349 kfree(name_node->name); 350 netdev_name_node_free(name_node); 351 } 352 353 int netdev_name_node_alt_destroy(struct net_device *dev, const char *name) 354 { 355 struct netdev_name_node *name_node; 356 struct net *net = dev_net(dev); 357 358 name_node = netdev_name_node_lookup(net, name); 359 if (!name_node) 360 return -ENOENT; 361 /* lookup might have found our primary name or a name belonging 362 * to another device. 363 */ 364 if (name_node == dev->name_node || name_node->dev != dev) 365 return -EINVAL; 366 367 __netdev_name_node_alt_destroy(name_node); 368 369 return 0; 370 } 371 372 static void netdev_name_node_alt_flush(struct net_device *dev) 373 { 374 struct netdev_name_node *name_node, *tmp; 375 376 list_for_each_entry_safe(name_node, tmp, &dev->name_node->list, list) 377 __netdev_name_node_alt_destroy(name_node); 378 } 379 380 /* Device list insertion */ 381 static void list_netdevice(struct net_device *dev) 382 { 383 struct net *net = dev_net(dev); 384 385 ASSERT_RTNL(); 386 387 write_lock(&dev_base_lock); 388 list_add_tail_rcu(&dev->dev_list, &net->dev_base_head); 389 netdev_name_node_add(net, dev->name_node); 390 hlist_add_head_rcu(&dev->index_hlist, 391 dev_index_hash(net, dev->ifindex)); 392 write_unlock(&dev_base_lock); 393 394 dev_base_seq_inc(net); 395 } 396 397 /* Device list removal 398 * caller must respect a RCU grace period before freeing/reusing dev 399 */ 400 static void unlist_netdevice(struct net_device *dev, bool lock) 401 { 402 ASSERT_RTNL(); 403 404 /* Unlink dev from the device chain */ 405 if (lock) 406 write_lock(&dev_base_lock); 407 list_del_rcu(&dev->dev_list); 408 netdev_name_node_del(dev->name_node); 409 hlist_del_rcu(&dev->index_hlist); 410 if (lock) 411 write_unlock(&dev_base_lock); 412 413 dev_base_seq_inc(dev_net(dev)); 414 } 415 416 /* 417 * Our notifier list 418 */ 419 420 static RAW_NOTIFIER_HEAD(netdev_chain); 421 422 /* 423 * Device drivers call our routines to queue packets here. We empty the 424 * queue in the local softnet handler. 425 */ 426 427 DEFINE_PER_CPU_ALIGNED(struct softnet_data, softnet_data); 428 EXPORT_PER_CPU_SYMBOL(softnet_data); 429 430 #ifdef CONFIG_LOCKDEP 431 /* 432 * register_netdevice() inits txq->_xmit_lock and sets lockdep class 433 * according to dev->type 434 */ 435 static const unsigned short netdev_lock_type[] = { 436 ARPHRD_NETROM, ARPHRD_ETHER, ARPHRD_EETHER, ARPHRD_AX25, 437 ARPHRD_PRONET, ARPHRD_CHAOS, ARPHRD_IEEE802, ARPHRD_ARCNET, 438 ARPHRD_APPLETLK, ARPHRD_DLCI, ARPHRD_ATM, ARPHRD_METRICOM, 439 ARPHRD_IEEE1394, ARPHRD_EUI64, ARPHRD_INFINIBAND, ARPHRD_SLIP, 440 ARPHRD_CSLIP, ARPHRD_SLIP6, ARPHRD_CSLIP6, ARPHRD_RSRVD, 441 ARPHRD_ADAPT, ARPHRD_ROSE, ARPHRD_X25, ARPHRD_HWX25, 442 ARPHRD_PPP, ARPHRD_CISCO, ARPHRD_LAPB, ARPHRD_DDCMP, 443 ARPHRD_RAWHDLC, ARPHRD_TUNNEL, ARPHRD_TUNNEL6, ARPHRD_FRAD, 444 ARPHRD_SKIP, ARPHRD_LOOPBACK, ARPHRD_LOCALTLK, ARPHRD_FDDI, 445 ARPHRD_BIF, ARPHRD_SIT, ARPHRD_IPDDP, ARPHRD_IPGRE, 446 ARPHRD_PIMREG, ARPHRD_HIPPI, ARPHRD_ASH, ARPHRD_ECONET, 447 ARPHRD_IRDA, ARPHRD_FCPP, ARPHRD_FCAL, ARPHRD_FCPL, 448 ARPHRD_FCFABRIC, ARPHRD_IEEE80211, ARPHRD_IEEE80211_PRISM, 449 ARPHRD_IEEE80211_RADIOTAP, ARPHRD_PHONET, ARPHRD_PHONET_PIPE, 450 ARPHRD_IEEE802154, ARPHRD_VOID, ARPHRD_NONE}; 451 452 static const char *const netdev_lock_name[] = { 453 "_xmit_NETROM", "_xmit_ETHER", "_xmit_EETHER", "_xmit_AX25", 454 "_xmit_PRONET", "_xmit_CHAOS", "_xmit_IEEE802", "_xmit_ARCNET", 455 "_xmit_APPLETLK", "_xmit_DLCI", "_xmit_ATM", "_xmit_METRICOM", 456 "_xmit_IEEE1394", "_xmit_EUI64", "_xmit_INFINIBAND", "_xmit_SLIP", 457 "_xmit_CSLIP", "_xmit_SLIP6", "_xmit_CSLIP6", "_xmit_RSRVD", 458 "_xmit_ADAPT", "_xmit_ROSE", "_xmit_X25", "_xmit_HWX25", 459 "_xmit_PPP", "_xmit_CISCO", "_xmit_LAPB", "_xmit_DDCMP", 460 "_xmit_RAWHDLC", "_xmit_TUNNEL", "_xmit_TUNNEL6", "_xmit_FRAD", 461 "_xmit_SKIP", "_xmit_LOOPBACK", "_xmit_LOCALTLK", "_xmit_FDDI", 462 "_xmit_BIF", "_xmit_SIT", "_xmit_IPDDP", "_xmit_IPGRE", 463 "_xmit_PIMREG", "_xmit_HIPPI", "_xmit_ASH", "_xmit_ECONET", 464 "_xmit_IRDA", "_xmit_FCPP", "_xmit_FCAL", "_xmit_FCPL", 465 "_xmit_FCFABRIC", "_xmit_IEEE80211", "_xmit_IEEE80211_PRISM", 466 "_xmit_IEEE80211_RADIOTAP", "_xmit_PHONET", "_xmit_PHONET_PIPE", 467 "_xmit_IEEE802154", "_xmit_VOID", "_xmit_NONE"}; 468 469 static struct lock_class_key netdev_xmit_lock_key[ARRAY_SIZE(netdev_lock_type)]; 470 static struct lock_class_key netdev_addr_lock_key[ARRAY_SIZE(netdev_lock_type)]; 471 472 static inline unsigned short netdev_lock_pos(unsigned short dev_type) 473 { 474 int i; 475 476 for (i = 0; i < ARRAY_SIZE(netdev_lock_type); i++) 477 if (netdev_lock_type[i] == dev_type) 478 return i; 479 /* the last key is used by default */ 480 return ARRAY_SIZE(netdev_lock_type) - 1; 481 } 482 483 static inline void netdev_set_xmit_lockdep_class(spinlock_t *lock, 484 unsigned short dev_type) 485 { 486 int i; 487 488 i = netdev_lock_pos(dev_type); 489 lockdep_set_class_and_name(lock, &netdev_xmit_lock_key[i], 490 netdev_lock_name[i]); 491 } 492 493 static inline void netdev_set_addr_lockdep_class(struct net_device *dev) 494 { 495 int i; 496 497 i = netdev_lock_pos(dev->type); 498 lockdep_set_class_and_name(&dev->addr_list_lock, 499 &netdev_addr_lock_key[i], 500 netdev_lock_name[i]); 501 } 502 #else 503 static inline void netdev_set_xmit_lockdep_class(spinlock_t *lock, 504 unsigned short dev_type) 505 { 506 } 507 508 static inline void netdev_set_addr_lockdep_class(struct net_device *dev) 509 { 510 } 511 #endif 512 513 /******************************************************************************* 514 * 515 * Protocol management and registration routines 516 * 517 *******************************************************************************/ 518 519 520 /* 521 * Add a protocol ID to the list. Now that the input handler is 522 * smarter we can dispense with all the messy stuff that used to be 523 * here. 524 * 525 * BEWARE!!! Protocol handlers, mangling input packets, 526 * MUST BE last in hash buckets and checking protocol handlers 527 * MUST start from promiscuous ptype_all chain in net_bh. 528 * It is true now, do not change it. 529 * Explanation follows: if protocol handler, mangling packet, will 530 * be the first on list, it is not able to sense, that packet 531 * is cloned and should be copied-on-write, so that it will 532 * change it and subsequent readers will get broken packet. 533 * --ANK (980803) 534 */ 535 536 static inline struct list_head *ptype_head(const struct packet_type *pt) 537 { 538 if (pt->type == htons(ETH_P_ALL)) 539 return pt->dev ? &pt->dev->ptype_all : &ptype_all; 540 else 541 return pt->dev ? &pt->dev->ptype_specific : 542 &ptype_base[ntohs(pt->type) & PTYPE_HASH_MASK]; 543 } 544 545 /** 546 * dev_add_pack - add packet handler 547 * @pt: packet type declaration 548 * 549 * Add a protocol handler to the networking stack. The passed &packet_type 550 * is linked into kernel lists and may not be freed until it has been 551 * removed from the kernel lists. 552 * 553 * This call does not sleep therefore it can not 554 * guarantee all CPU's that are in middle of receiving packets 555 * will see the new packet type (until the next received packet). 556 */ 557 558 void dev_add_pack(struct packet_type *pt) 559 { 560 struct list_head *head = ptype_head(pt); 561 562 spin_lock(&ptype_lock); 563 list_add_rcu(&pt->list, head); 564 spin_unlock(&ptype_lock); 565 } 566 EXPORT_SYMBOL(dev_add_pack); 567 568 /** 569 * __dev_remove_pack - remove packet handler 570 * @pt: packet type declaration 571 * 572 * Remove a protocol handler that was previously added to the kernel 573 * protocol handlers by dev_add_pack(). The passed &packet_type is removed 574 * from the kernel lists and can be freed or reused once this function 575 * returns. 576 * 577 * The packet type might still be in use by receivers 578 * and must not be freed until after all the CPU's have gone 579 * through a quiescent state. 580 */ 581 void __dev_remove_pack(struct packet_type *pt) 582 { 583 struct list_head *head = ptype_head(pt); 584 struct packet_type *pt1; 585 586 spin_lock(&ptype_lock); 587 588 list_for_each_entry(pt1, head, list) { 589 if (pt == pt1) { 590 list_del_rcu(&pt->list); 591 goto out; 592 } 593 } 594 595 pr_warn("dev_remove_pack: %p not found\n", pt); 596 out: 597 spin_unlock(&ptype_lock); 598 } 599 EXPORT_SYMBOL(__dev_remove_pack); 600 601 /** 602 * dev_remove_pack - remove packet handler 603 * @pt: packet type declaration 604 * 605 * Remove a protocol handler that was previously added to the kernel 606 * protocol handlers by dev_add_pack(). The passed &packet_type is removed 607 * from the kernel lists and can be freed or reused once this function 608 * returns. 609 * 610 * This call sleeps to guarantee that no CPU is looking at the packet 611 * type after return. 612 */ 613 void dev_remove_pack(struct packet_type *pt) 614 { 615 __dev_remove_pack(pt); 616 617 synchronize_net(); 618 } 619 EXPORT_SYMBOL(dev_remove_pack); 620 621 622 /******************************************************************************* 623 * 624 * Device Interface Subroutines 625 * 626 *******************************************************************************/ 627 628 /** 629 * dev_get_iflink - get 'iflink' value of a interface 630 * @dev: targeted interface 631 * 632 * Indicates the ifindex the interface is linked to. 633 * Physical interfaces have the same 'ifindex' and 'iflink' values. 634 */ 635 636 int dev_get_iflink(const struct net_device *dev) 637 { 638 if (dev->netdev_ops && dev->netdev_ops->ndo_get_iflink) 639 return dev->netdev_ops->ndo_get_iflink(dev); 640 641 return dev->ifindex; 642 } 643 EXPORT_SYMBOL(dev_get_iflink); 644 645 /** 646 * dev_fill_metadata_dst - Retrieve tunnel egress information. 647 * @dev: targeted interface 648 * @skb: The packet. 649 * 650 * For better visibility of tunnel traffic OVS needs to retrieve 651 * egress tunnel information for a packet. Following API allows 652 * user to get this info. 653 */ 654 int dev_fill_metadata_dst(struct net_device *dev, struct sk_buff *skb) 655 { 656 struct ip_tunnel_info *info; 657 658 if (!dev->netdev_ops || !dev->netdev_ops->ndo_fill_metadata_dst) 659 return -EINVAL; 660 661 info = skb_tunnel_info_unclone(skb); 662 if (!info) 663 return -ENOMEM; 664 if (unlikely(!(info->mode & IP_TUNNEL_INFO_TX))) 665 return -EINVAL; 666 667 return dev->netdev_ops->ndo_fill_metadata_dst(dev, skb); 668 } 669 EXPORT_SYMBOL_GPL(dev_fill_metadata_dst); 670 671 static struct net_device_path *dev_fwd_path(struct net_device_path_stack *stack) 672 { 673 int k = stack->num_paths++; 674 675 if (WARN_ON_ONCE(k >= NET_DEVICE_PATH_STACK_MAX)) 676 return NULL; 677 678 return &stack->path[k]; 679 } 680 681 int dev_fill_forward_path(const struct net_device *dev, const u8 *daddr, 682 struct net_device_path_stack *stack) 683 { 684 const struct net_device *last_dev; 685 struct net_device_path_ctx ctx = { 686 .dev = dev, 687 }; 688 struct net_device_path *path; 689 int ret = 0; 690 691 memcpy(ctx.daddr, daddr, sizeof(ctx.daddr)); 692 stack->num_paths = 0; 693 while (ctx.dev && ctx.dev->netdev_ops->ndo_fill_forward_path) { 694 last_dev = ctx.dev; 695 path = dev_fwd_path(stack); 696 if (!path) 697 return -1; 698 699 memset(path, 0, sizeof(struct net_device_path)); 700 ret = ctx.dev->netdev_ops->ndo_fill_forward_path(&ctx, path); 701 if (ret < 0) 702 return -1; 703 704 if (WARN_ON_ONCE(last_dev == ctx.dev)) 705 return -1; 706 } 707 708 if (!ctx.dev) 709 return ret; 710 711 path = dev_fwd_path(stack); 712 if (!path) 713 return -1; 714 path->type = DEV_PATH_ETHERNET; 715 path->dev = ctx.dev; 716 717 return ret; 718 } 719 EXPORT_SYMBOL_GPL(dev_fill_forward_path); 720 721 /** 722 * __dev_get_by_name - find a device by its name 723 * @net: the applicable net namespace 724 * @name: name to find 725 * 726 * Find an interface by name. Must be called under RTNL semaphore 727 * or @dev_base_lock. If the name is found a pointer to the device 728 * is returned. If the name is not found then %NULL is returned. The 729 * reference counters are not incremented so the caller must be 730 * careful with locks. 731 */ 732 733 struct net_device *__dev_get_by_name(struct net *net, const char *name) 734 { 735 struct netdev_name_node *node_name; 736 737 node_name = netdev_name_node_lookup(net, name); 738 return node_name ? node_name->dev : NULL; 739 } 740 EXPORT_SYMBOL(__dev_get_by_name); 741 742 /** 743 * dev_get_by_name_rcu - find a device by its name 744 * @net: the applicable net namespace 745 * @name: name to find 746 * 747 * Find an interface by name. 748 * If the name is found a pointer to the device is returned. 749 * If the name is not found then %NULL is returned. 750 * The reference counters are not incremented so the caller must be 751 * careful with locks. The caller must hold RCU lock. 752 */ 753 754 struct net_device *dev_get_by_name_rcu(struct net *net, const char *name) 755 { 756 struct netdev_name_node *node_name; 757 758 node_name = netdev_name_node_lookup_rcu(net, name); 759 return node_name ? node_name->dev : NULL; 760 } 761 EXPORT_SYMBOL(dev_get_by_name_rcu); 762 763 /** 764 * dev_get_by_name - find a device by its name 765 * @net: the applicable net namespace 766 * @name: name to find 767 * 768 * Find an interface by name. This can be called from any 769 * context and does its own locking. The returned handle has 770 * the usage count incremented and the caller must use dev_put() to 771 * release it when it is no longer needed. %NULL is returned if no 772 * matching device is found. 773 */ 774 775 struct net_device *dev_get_by_name(struct net *net, const char *name) 776 { 777 struct net_device *dev; 778 779 rcu_read_lock(); 780 dev = dev_get_by_name_rcu(net, name); 781 dev_hold(dev); 782 rcu_read_unlock(); 783 return dev; 784 } 785 EXPORT_SYMBOL(dev_get_by_name); 786 787 /** 788 * __dev_get_by_index - find a device by its ifindex 789 * @net: the applicable net namespace 790 * @ifindex: index of device 791 * 792 * Search for an interface by index. Returns %NULL if the device 793 * is not found or a pointer to the device. The device has not 794 * had its reference counter increased so the caller must be careful 795 * about locking. The caller must hold either the RTNL semaphore 796 * or @dev_base_lock. 797 */ 798 799 struct net_device *__dev_get_by_index(struct net *net, int ifindex) 800 { 801 struct net_device *dev; 802 struct hlist_head *head = dev_index_hash(net, ifindex); 803 804 hlist_for_each_entry(dev, head, index_hlist) 805 if (dev->ifindex == ifindex) 806 return dev; 807 808 return NULL; 809 } 810 EXPORT_SYMBOL(__dev_get_by_index); 811 812 /** 813 * dev_get_by_index_rcu - find a device by its ifindex 814 * @net: the applicable net namespace 815 * @ifindex: index of device 816 * 817 * Search for an interface by index. Returns %NULL if the device 818 * is not found or a pointer to the device. The device has not 819 * had its reference counter increased so the caller must be careful 820 * about locking. The caller must hold RCU lock. 821 */ 822 823 struct net_device *dev_get_by_index_rcu(struct net *net, int ifindex) 824 { 825 struct net_device *dev; 826 struct hlist_head *head = dev_index_hash(net, ifindex); 827 828 hlist_for_each_entry_rcu(dev, head, index_hlist) 829 if (dev->ifindex == ifindex) 830 return dev; 831 832 return NULL; 833 } 834 EXPORT_SYMBOL(dev_get_by_index_rcu); 835 836 837 /** 838 * dev_get_by_index - find a device by its ifindex 839 * @net: the applicable net namespace 840 * @ifindex: index of device 841 * 842 * Search for an interface by index. Returns NULL if the device 843 * is not found or a pointer to the device. The device returned has 844 * had a reference added and the pointer is safe until the user calls 845 * dev_put to indicate they have finished with it. 846 */ 847 848 struct net_device *dev_get_by_index(struct net *net, int ifindex) 849 { 850 struct net_device *dev; 851 852 rcu_read_lock(); 853 dev = dev_get_by_index_rcu(net, ifindex); 854 dev_hold(dev); 855 rcu_read_unlock(); 856 return dev; 857 } 858 EXPORT_SYMBOL(dev_get_by_index); 859 860 /** 861 * dev_get_by_napi_id - find a device by napi_id 862 * @napi_id: ID of the NAPI struct 863 * 864 * Search for an interface by NAPI ID. Returns %NULL if the device 865 * is not found or a pointer to the device. The device has not had 866 * its reference counter increased so the caller must be careful 867 * about locking. The caller must hold RCU lock. 868 */ 869 870 struct net_device *dev_get_by_napi_id(unsigned int napi_id) 871 { 872 struct napi_struct *napi; 873 874 WARN_ON_ONCE(!rcu_read_lock_held()); 875 876 if (napi_id < MIN_NAPI_ID) 877 return NULL; 878 879 napi = napi_by_id(napi_id); 880 881 return napi ? napi->dev : NULL; 882 } 883 EXPORT_SYMBOL(dev_get_by_napi_id); 884 885 /** 886 * netdev_get_name - get a netdevice name, knowing its ifindex. 887 * @net: network namespace 888 * @name: a pointer to the buffer where the name will be stored. 889 * @ifindex: the ifindex of the interface to get the name from. 890 */ 891 int netdev_get_name(struct net *net, char *name, int ifindex) 892 { 893 struct net_device *dev; 894 int ret; 895 896 down_read(&devnet_rename_sem); 897 rcu_read_lock(); 898 899 dev = dev_get_by_index_rcu(net, ifindex); 900 if (!dev) { 901 ret = -ENODEV; 902 goto out; 903 } 904 905 strcpy(name, dev->name); 906 907 ret = 0; 908 out: 909 rcu_read_unlock(); 910 up_read(&devnet_rename_sem); 911 return ret; 912 } 913 914 /** 915 * dev_getbyhwaddr_rcu - find a device by its hardware address 916 * @net: the applicable net namespace 917 * @type: media type of device 918 * @ha: hardware address 919 * 920 * Search for an interface by MAC address. Returns NULL if the device 921 * is not found or a pointer to the device. 922 * The caller must hold RCU or RTNL. 923 * The returned device has not had its ref count increased 924 * and the caller must therefore be careful about locking 925 * 926 */ 927 928 struct net_device *dev_getbyhwaddr_rcu(struct net *net, unsigned short type, 929 const char *ha) 930 { 931 struct net_device *dev; 932 933 for_each_netdev_rcu(net, dev) 934 if (dev->type == type && 935 !memcmp(dev->dev_addr, ha, dev->addr_len)) 936 return dev; 937 938 return NULL; 939 } 940 EXPORT_SYMBOL(dev_getbyhwaddr_rcu); 941 942 struct net_device *dev_getfirstbyhwtype(struct net *net, unsigned short type) 943 { 944 struct net_device *dev, *ret = NULL; 945 946 rcu_read_lock(); 947 for_each_netdev_rcu(net, dev) 948 if (dev->type == type) { 949 dev_hold(dev); 950 ret = dev; 951 break; 952 } 953 rcu_read_unlock(); 954 return ret; 955 } 956 EXPORT_SYMBOL(dev_getfirstbyhwtype); 957 958 /** 959 * __dev_get_by_flags - find any device with given flags 960 * @net: the applicable net namespace 961 * @if_flags: IFF_* values 962 * @mask: bitmask of bits in if_flags to check 963 * 964 * Search for any interface with the given flags. Returns NULL if a device 965 * is not found or a pointer to the device. Must be called inside 966 * rtnl_lock(), and result refcount is unchanged. 967 */ 968 969 struct net_device *__dev_get_by_flags(struct net *net, unsigned short if_flags, 970 unsigned short mask) 971 { 972 struct net_device *dev, *ret; 973 974 ASSERT_RTNL(); 975 976 ret = NULL; 977 for_each_netdev(net, dev) { 978 if (((dev->flags ^ if_flags) & mask) == 0) { 979 ret = dev; 980 break; 981 } 982 } 983 return ret; 984 } 985 EXPORT_SYMBOL(__dev_get_by_flags); 986 987 /** 988 * dev_valid_name - check if name is okay for network device 989 * @name: name string 990 * 991 * Network device names need to be valid file names to 992 * allow sysfs to work. We also disallow any kind of 993 * whitespace. 994 */ 995 bool dev_valid_name(const char *name) 996 { 997 if (*name == '\0') 998 return false; 999 if (strnlen(name, IFNAMSIZ) == IFNAMSIZ) 1000 return false; 1001 if (!strcmp(name, ".") || !strcmp(name, "..")) 1002 return false; 1003 1004 while (*name) { 1005 if (*name == '/' || *name == ':' || isspace(*name)) 1006 return false; 1007 name++; 1008 } 1009 return true; 1010 } 1011 EXPORT_SYMBOL(dev_valid_name); 1012 1013 /** 1014 * __dev_alloc_name - allocate a name for a device 1015 * @net: network namespace to allocate the device name in 1016 * @name: name format string 1017 * @buf: scratch buffer and result name string 1018 * 1019 * Passed a format string - eg "lt%d" it will try and find a suitable 1020 * id. It scans list of devices to build up a free map, then chooses 1021 * the first empty slot. The caller must hold the dev_base or rtnl lock 1022 * while allocating the name and adding the device in order to avoid 1023 * duplicates. 1024 * Limited to bits_per_byte * page size devices (ie 32K on most platforms). 1025 * Returns the number of the unit assigned or a negative errno code. 1026 */ 1027 1028 static int __dev_alloc_name(struct net *net, const char *name, char *buf) 1029 { 1030 int i = 0; 1031 const char *p; 1032 const int max_netdevices = 8*PAGE_SIZE; 1033 unsigned long *inuse; 1034 struct net_device *d; 1035 1036 if (!dev_valid_name(name)) 1037 return -EINVAL; 1038 1039 p = strchr(name, '%'); 1040 if (p) { 1041 /* 1042 * Verify the string as this thing may have come from 1043 * the user. There must be either one "%d" and no other "%" 1044 * characters. 1045 */ 1046 if (p[1] != 'd' || strchr(p + 2, '%')) 1047 return -EINVAL; 1048 1049 /* Use one page as a bit array of possible slots */ 1050 inuse = (unsigned long *) get_zeroed_page(GFP_ATOMIC); 1051 if (!inuse) 1052 return -ENOMEM; 1053 1054 for_each_netdev(net, d) { 1055 struct netdev_name_node *name_node; 1056 list_for_each_entry(name_node, &d->name_node->list, list) { 1057 if (!sscanf(name_node->name, name, &i)) 1058 continue; 1059 if (i < 0 || i >= max_netdevices) 1060 continue; 1061 1062 /* avoid cases where sscanf is not exact inverse of printf */ 1063 snprintf(buf, IFNAMSIZ, name, i); 1064 if (!strncmp(buf, name_node->name, IFNAMSIZ)) 1065 __set_bit(i, inuse); 1066 } 1067 if (!sscanf(d->name, name, &i)) 1068 continue; 1069 if (i < 0 || i >= max_netdevices) 1070 continue; 1071 1072 /* avoid cases where sscanf is not exact inverse of printf */ 1073 snprintf(buf, IFNAMSIZ, name, i); 1074 if (!strncmp(buf, d->name, IFNAMSIZ)) 1075 __set_bit(i, inuse); 1076 } 1077 1078 i = find_first_zero_bit(inuse, max_netdevices); 1079 free_page((unsigned long) inuse); 1080 } 1081 1082 snprintf(buf, IFNAMSIZ, name, i); 1083 if (!netdev_name_in_use(net, buf)) 1084 return i; 1085 1086 /* It is possible to run out of possible slots 1087 * when the name is long and there isn't enough space left 1088 * for the digits, or if all bits are used. 1089 */ 1090 return -ENFILE; 1091 } 1092 1093 static int dev_alloc_name_ns(struct net *net, 1094 struct net_device *dev, 1095 const char *name) 1096 { 1097 char buf[IFNAMSIZ]; 1098 int ret; 1099 1100 BUG_ON(!net); 1101 ret = __dev_alloc_name(net, name, buf); 1102 if (ret >= 0) 1103 strscpy(dev->name, buf, IFNAMSIZ); 1104 return ret; 1105 } 1106 1107 /** 1108 * dev_alloc_name - allocate a name for a device 1109 * @dev: device 1110 * @name: name format string 1111 * 1112 * Passed a format string - eg "lt%d" it will try and find a suitable 1113 * id. It scans list of devices to build up a free map, then chooses 1114 * the first empty slot. The caller must hold the dev_base or rtnl lock 1115 * while allocating the name and adding the device in order to avoid 1116 * duplicates. 1117 * Limited to bits_per_byte * page size devices (ie 32K on most platforms). 1118 * Returns the number of the unit assigned or a negative errno code. 1119 */ 1120 1121 int dev_alloc_name(struct net_device *dev, const char *name) 1122 { 1123 return dev_alloc_name_ns(dev_net(dev), dev, name); 1124 } 1125 EXPORT_SYMBOL(dev_alloc_name); 1126 1127 static int dev_get_valid_name(struct net *net, struct net_device *dev, 1128 const char *name) 1129 { 1130 BUG_ON(!net); 1131 1132 if (!dev_valid_name(name)) 1133 return -EINVAL; 1134 1135 if (strchr(name, '%')) 1136 return dev_alloc_name_ns(net, dev, name); 1137 else if (netdev_name_in_use(net, name)) 1138 return -EEXIST; 1139 else if (dev->name != name) 1140 strscpy(dev->name, name, IFNAMSIZ); 1141 1142 return 0; 1143 } 1144 1145 /** 1146 * dev_change_name - change name of a device 1147 * @dev: device 1148 * @newname: name (or format string) must be at least IFNAMSIZ 1149 * 1150 * Change name of a device, can pass format strings "eth%d". 1151 * for wildcarding. 1152 */ 1153 int dev_change_name(struct net_device *dev, const char *newname) 1154 { 1155 unsigned char old_assign_type; 1156 char oldname[IFNAMSIZ]; 1157 int err = 0; 1158 int ret; 1159 struct net *net; 1160 1161 ASSERT_RTNL(); 1162 BUG_ON(!dev_net(dev)); 1163 1164 net = dev_net(dev); 1165 1166 down_write(&devnet_rename_sem); 1167 1168 if (strncmp(newname, dev->name, IFNAMSIZ) == 0) { 1169 up_write(&devnet_rename_sem); 1170 return 0; 1171 } 1172 1173 memcpy(oldname, dev->name, IFNAMSIZ); 1174 1175 err = dev_get_valid_name(net, dev, newname); 1176 if (err < 0) { 1177 up_write(&devnet_rename_sem); 1178 return err; 1179 } 1180 1181 if (oldname[0] && !strchr(oldname, '%')) 1182 netdev_info(dev, "renamed from %s%s\n", oldname, 1183 dev->flags & IFF_UP ? " (while UP)" : ""); 1184 1185 old_assign_type = dev->name_assign_type; 1186 dev->name_assign_type = NET_NAME_RENAMED; 1187 1188 rollback: 1189 ret = device_rename(&dev->dev, dev->name); 1190 if (ret) { 1191 memcpy(dev->name, oldname, IFNAMSIZ); 1192 dev->name_assign_type = old_assign_type; 1193 up_write(&devnet_rename_sem); 1194 return ret; 1195 } 1196 1197 up_write(&devnet_rename_sem); 1198 1199 netdev_adjacent_rename_links(dev, oldname); 1200 1201 write_lock(&dev_base_lock); 1202 netdev_name_node_del(dev->name_node); 1203 write_unlock(&dev_base_lock); 1204 1205 synchronize_rcu(); 1206 1207 write_lock(&dev_base_lock); 1208 netdev_name_node_add(net, dev->name_node); 1209 write_unlock(&dev_base_lock); 1210 1211 ret = call_netdevice_notifiers(NETDEV_CHANGENAME, dev); 1212 ret = notifier_to_errno(ret); 1213 1214 if (ret) { 1215 /* err >= 0 after dev_alloc_name() or stores the first errno */ 1216 if (err >= 0) { 1217 err = ret; 1218 down_write(&devnet_rename_sem); 1219 memcpy(dev->name, oldname, IFNAMSIZ); 1220 memcpy(oldname, newname, IFNAMSIZ); 1221 dev->name_assign_type = old_assign_type; 1222 old_assign_type = NET_NAME_RENAMED; 1223 goto rollback; 1224 } else { 1225 netdev_err(dev, "name change rollback failed: %d\n", 1226 ret); 1227 } 1228 } 1229 1230 return err; 1231 } 1232 1233 /** 1234 * dev_set_alias - change ifalias of a device 1235 * @dev: device 1236 * @alias: name up to IFALIASZ 1237 * @len: limit of bytes to copy from info 1238 * 1239 * Set ifalias for a device, 1240 */ 1241 int dev_set_alias(struct net_device *dev, const char *alias, size_t len) 1242 { 1243 struct dev_ifalias *new_alias = NULL; 1244 1245 if (len >= IFALIASZ) 1246 return -EINVAL; 1247 1248 if (len) { 1249 new_alias = kmalloc(sizeof(*new_alias) + len + 1, GFP_KERNEL); 1250 if (!new_alias) 1251 return -ENOMEM; 1252 1253 memcpy(new_alias->ifalias, alias, len); 1254 new_alias->ifalias[len] = 0; 1255 } 1256 1257 mutex_lock(&ifalias_mutex); 1258 new_alias = rcu_replace_pointer(dev->ifalias, new_alias, 1259 mutex_is_locked(&ifalias_mutex)); 1260 mutex_unlock(&ifalias_mutex); 1261 1262 if (new_alias) 1263 kfree_rcu(new_alias, rcuhead); 1264 1265 return len; 1266 } 1267 EXPORT_SYMBOL(dev_set_alias); 1268 1269 /** 1270 * dev_get_alias - get ifalias of a device 1271 * @dev: device 1272 * @name: buffer to store name of ifalias 1273 * @len: size of buffer 1274 * 1275 * get ifalias for a device. Caller must make sure dev cannot go 1276 * away, e.g. rcu read lock or own a reference count to device. 1277 */ 1278 int dev_get_alias(const struct net_device *dev, char *name, size_t len) 1279 { 1280 const struct dev_ifalias *alias; 1281 int ret = 0; 1282 1283 rcu_read_lock(); 1284 alias = rcu_dereference(dev->ifalias); 1285 if (alias) 1286 ret = snprintf(name, len, "%s", alias->ifalias); 1287 rcu_read_unlock(); 1288 1289 return ret; 1290 } 1291 1292 /** 1293 * netdev_features_change - device changes features 1294 * @dev: device to cause notification 1295 * 1296 * Called to indicate a device has changed features. 1297 */ 1298 void netdev_features_change(struct net_device *dev) 1299 { 1300 call_netdevice_notifiers(NETDEV_FEAT_CHANGE, dev); 1301 } 1302 EXPORT_SYMBOL(netdev_features_change); 1303 1304 /** 1305 * netdev_state_change - device changes state 1306 * @dev: device to cause notification 1307 * 1308 * Called to indicate a device has changed state. This function calls 1309 * the notifier chains for netdev_chain and sends a NEWLINK message 1310 * to the routing socket. 1311 */ 1312 void netdev_state_change(struct net_device *dev) 1313 { 1314 if (dev->flags & IFF_UP) { 1315 struct netdev_notifier_change_info change_info = { 1316 .info.dev = dev, 1317 }; 1318 1319 call_netdevice_notifiers_info(NETDEV_CHANGE, 1320 &change_info.info); 1321 rtmsg_ifinfo(RTM_NEWLINK, dev, 0, GFP_KERNEL, 0, NULL); 1322 } 1323 } 1324 EXPORT_SYMBOL(netdev_state_change); 1325 1326 /** 1327 * __netdev_notify_peers - notify network peers about existence of @dev, 1328 * to be called when rtnl lock is already held. 1329 * @dev: network device 1330 * 1331 * Generate traffic such that interested network peers are aware of 1332 * @dev, such as by generating a gratuitous ARP. This may be used when 1333 * a device wants to inform the rest of the network about some sort of 1334 * reconfiguration such as a failover event or virtual machine 1335 * migration. 1336 */ 1337 void __netdev_notify_peers(struct net_device *dev) 1338 { 1339 ASSERT_RTNL(); 1340 call_netdevice_notifiers(NETDEV_NOTIFY_PEERS, dev); 1341 call_netdevice_notifiers(NETDEV_RESEND_IGMP, dev); 1342 } 1343 EXPORT_SYMBOL(__netdev_notify_peers); 1344 1345 /** 1346 * netdev_notify_peers - notify network peers about existence of @dev 1347 * @dev: network device 1348 * 1349 * Generate traffic such that interested network peers are aware of 1350 * @dev, such as by generating a gratuitous ARP. This may be used when 1351 * a device wants to inform the rest of the network about some sort of 1352 * reconfiguration such as a failover event or virtual machine 1353 * migration. 1354 */ 1355 void netdev_notify_peers(struct net_device *dev) 1356 { 1357 rtnl_lock(); 1358 __netdev_notify_peers(dev); 1359 rtnl_unlock(); 1360 } 1361 EXPORT_SYMBOL(netdev_notify_peers); 1362 1363 static int napi_threaded_poll(void *data); 1364 1365 static int napi_kthread_create(struct napi_struct *n) 1366 { 1367 int err = 0; 1368 1369 /* Create and wake up the kthread once to put it in 1370 * TASK_INTERRUPTIBLE mode to avoid the blocked task 1371 * warning and work with loadavg. 1372 */ 1373 n->thread = kthread_run(napi_threaded_poll, n, "napi/%s-%d", 1374 n->dev->name, n->napi_id); 1375 if (IS_ERR(n->thread)) { 1376 err = PTR_ERR(n->thread); 1377 pr_err("kthread_run failed with err %d\n", err); 1378 n->thread = NULL; 1379 } 1380 1381 return err; 1382 } 1383 1384 static int __dev_open(struct net_device *dev, struct netlink_ext_ack *extack) 1385 { 1386 const struct net_device_ops *ops = dev->netdev_ops; 1387 int ret; 1388 1389 ASSERT_RTNL(); 1390 dev_addr_check(dev); 1391 1392 if (!netif_device_present(dev)) { 1393 /* may be detached because parent is runtime-suspended */ 1394 if (dev->dev.parent) 1395 pm_runtime_resume(dev->dev.parent); 1396 if (!netif_device_present(dev)) 1397 return -ENODEV; 1398 } 1399 1400 /* Block netpoll from trying to do any rx path servicing. 1401 * If we don't do this there is a chance ndo_poll_controller 1402 * or ndo_poll may be running while we open the device 1403 */ 1404 netpoll_poll_disable(dev); 1405 1406 ret = call_netdevice_notifiers_extack(NETDEV_PRE_UP, dev, extack); 1407 ret = notifier_to_errno(ret); 1408 if (ret) 1409 return ret; 1410 1411 set_bit(__LINK_STATE_START, &dev->state); 1412 1413 if (ops->ndo_validate_addr) 1414 ret = ops->ndo_validate_addr(dev); 1415 1416 if (!ret && ops->ndo_open) 1417 ret = ops->ndo_open(dev); 1418 1419 netpoll_poll_enable(dev); 1420 1421 if (ret) 1422 clear_bit(__LINK_STATE_START, &dev->state); 1423 else { 1424 dev->flags |= IFF_UP; 1425 dev_set_rx_mode(dev); 1426 dev_activate(dev); 1427 add_device_randomness(dev->dev_addr, dev->addr_len); 1428 } 1429 1430 return ret; 1431 } 1432 1433 /** 1434 * dev_open - prepare an interface for use. 1435 * @dev: device to open 1436 * @extack: netlink extended ack 1437 * 1438 * Takes a device from down to up state. The device's private open 1439 * function is invoked and then the multicast lists are loaded. Finally 1440 * the device is moved into the up state and a %NETDEV_UP message is 1441 * sent to the netdev notifier chain. 1442 * 1443 * Calling this function on an active interface is a nop. On a failure 1444 * a negative errno code is returned. 1445 */ 1446 int dev_open(struct net_device *dev, struct netlink_ext_ack *extack) 1447 { 1448 int ret; 1449 1450 if (dev->flags & IFF_UP) 1451 return 0; 1452 1453 ret = __dev_open(dev, extack); 1454 if (ret < 0) 1455 return ret; 1456 1457 rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP | IFF_RUNNING, GFP_KERNEL, 0, NULL); 1458 call_netdevice_notifiers(NETDEV_UP, dev); 1459 1460 return ret; 1461 } 1462 EXPORT_SYMBOL(dev_open); 1463 1464 static void __dev_close_many(struct list_head *head) 1465 { 1466 struct net_device *dev; 1467 1468 ASSERT_RTNL(); 1469 might_sleep(); 1470 1471 list_for_each_entry(dev, head, close_list) { 1472 /* Temporarily disable netpoll until the interface is down */ 1473 netpoll_poll_disable(dev); 1474 1475 call_netdevice_notifiers(NETDEV_GOING_DOWN, dev); 1476 1477 clear_bit(__LINK_STATE_START, &dev->state); 1478 1479 /* Synchronize to scheduled poll. We cannot touch poll list, it 1480 * can be even on different cpu. So just clear netif_running(). 1481 * 1482 * dev->stop() will invoke napi_disable() on all of it's 1483 * napi_struct instances on this device. 1484 */ 1485 smp_mb__after_atomic(); /* Commit netif_running(). */ 1486 } 1487 1488 dev_deactivate_many(head); 1489 1490 list_for_each_entry(dev, head, close_list) { 1491 const struct net_device_ops *ops = dev->netdev_ops; 1492 1493 /* 1494 * Call the device specific close. This cannot fail. 1495 * Only if device is UP 1496 * 1497 * We allow it to be called even after a DETACH hot-plug 1498 * event. 1499 */ 1500 if (ops->ndo_stop) 1501 ops->ndo_stop(dev); 1502 1503 dev->flags &= ~IFF_UP; 1504 netpoll_poll_enable(dev); 1505 } 1506 } 1507 1508 static void __dev_close(struct net_device *dev) 1509 { 1510 LIST_HEAD(single); 1511 1512 list_add(&dev->close_list, &single); 1513 __dev_close_many(&single); 1514 list_del(&single); 1515 } 1516 1517 void dev_close_many(struct list_head *head, bool unlink) 1518 { 1519 struct net_device *dev, *tmp; 1520 1521 /* Remove the devices that don't need to be closed */ 1522 list_for_each_entry_safe(dev, tmp, head, close_list) 1523 if (!(dev->flags & IFF_UP)) 1524 list_del_init(&dev->close_list); 1525 1526 __dev_close_many(head); 1527 1528 list_for_each_entry_safe(dev, tmp, head, close_list) { 1529 rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP | IFF_RUNNING, GFP_KERNEL, 0, NULL); 1530 call_netdevice_notifiers(NETDEV_DOWN, dev); 1531 if (unlink) 1532 list_del_init(&dev->close_list); 1533 } 1534 } 1535 EXPORT_SYMBOL(dev_close_many); 1536 1537 /** 1538 * dev_close - shutdown an interface. 1539 * @dev: device to shutdown 1540 * 1541 * This function moves an active device into down state. A 1542 * %NETDEV_GOING_DOWN is sent to the netdev notifier chain. The device 1543 * is then deactivated and finally a %NETDEV_DOWN is sent to the notifier 1544 * chain. 1545 */ 1546 void dev_close(struct net_device *dev) 1547 { 1548 if (dev->flags & IFF_UP) { 1549 LIST_HEAD(single); 1550 1551 list_add(&dev->close_list, &single); 1552 dev_close_many(&single, true); 1553 list_del(&single); 1554 } 1555 } 1556 EXPORT_SYMBOL(dev_close); 1557 1558 1559 /** 1560 * dev_disable_lro - disable Large Receive Offload on a device 1561 * @dev: device 1562 * 1563 * Disable Large Receive Offload (LRO) on a net device. Must be 1564 * called under RTNL. This is needed if received packets may be 1565 * forwarded to another interface. 1566 */ 1567 void dev_disable_lro(struct net_device *dev) 1568 { 1569 struct net_device *lower_dev; 1570 struct list_head *iter; 1571 1572 dev->wanted_features &= ~NETIF_F_LRO; 1573 netdev_update_features(dev); 1574 1575 if (unlikely(dev->features & NETIF_F_LRO)) 1576 netdev_WARN(dev, "failed to disable LRO!\n"); 1577 1578 netdev_for_each_lower_dev(dev, lower_dev, iter) 1579 dev_disable_lro(lower_dev); 1580 } 1581 EXPORT_SYMBOL(dev_disable_lro); 1582 1583 /** 1584 * dev_disable_gro_hw - disable HW Generic Receive Offload on a device 1585 * @dev: device 1586 * 1587 * Disable HW Generic Receive Offload (GRO_HW) on a net device. Must be 1588 * called under RTNL. This is needed if Generic XDP is installed on 1589 * the device. 1590 */ 1591 static void dev_disable_gro_hw(struct net_device *dev) 1592 { 1593 dev->wanted_features &= ~NETIF_F_GRO_HW; 1594 netdev_update_features(dev); 1595 1596 if (unlikely(dev->features & NETIF_F_GRO_HW)) 1597 netdev_WARN(dev, "failed to disable GRO_HW!\n"); 1598 } 1599 1600 const char *netdev_cmd_to_name(enum netdev_cmd cmd) 1601 { 1602 #define N(val) \ 1603 case NETDEV_##val: \ 1604 return "NETDEV_" __stringify(val); 1605 switch (cmd) { 1606 N(UP) N(DOWN) N(REBOOT) N(CHANGE) N(REGISTER) N(UNREGISTER) 1607 N(CHANGEMTU) N(CHANGEADDR) N(GOING_DOWN) N(CHANGENAME) N(FEAT_CHANGE) 1608 N(BONDING_FAILOVER) N(PRE_UP) N(PRE_TYPE_CHANGE) N(POST_TYPE_CHANGE) 1609 N(POST_INIT) N(PRE_UNINIT) N(RELEASE) N(NOTIFY_PEERS) N(JOIN) 1610 N(CHANGEUPPER) N(RESEND_IGMP) N(PRECHANGEMTU) N(CHANGEINFODATA) 1611 N(BONDING_INFO) N(PRECHANGEUPPER) N(CHANGELOWERSTATE) 1612 N(UDP_TUNNEL_PUSH_INFO) N(UDP_TUNNEL_DROP_INFO) N(CHANGE_TX_QUEUE_LEN) 1613 N(CVLAN_FILTER_PUSH_INFO) N(CVLAN_FILTER_DROP_INFO) 1614 N(SVLAN_FILTER_PUSH_INFO) N(SVLAN_FILTER_DROP_INFO) 1615 N(PRE_CHANGEADDR) N(OFFLOAD_XSTATS_ENABLE) N(OFFLOAD_XSTATS_DISABLE) 1616 N(OFFLOAD_XSTATS_REPORT_USED) N(OFFLOAD_XSTATS_REPORT_DELTA) 1617 } 1618 #undef N 1619 return "UNKNOWN_NETDEV_EVENT"; 1620 } 1621 EXPORT_SYMBOL_GPL(netdev_cmd_to_name); 1622 1623 static int call_netdevice_notifier(struct notifier_block *nb, unsigned long val, 1624 struct net_device *dev) 1625 { 1626 struct netdev_notifier_info info = { 1627 .dev = dev, 1628 }; 1629 1630 return nb->notifier_call(nb, val, &info); 1631 } 1632 1633 static int call_netdevice_register_notifiers(struct notifier_block *nb, 1634 struct net_device *dev) 1635 { 1636 int err; 1637 1638 err = call_netdevice_notifier(nb, NETDEV_REGISTER, dev); 1639 err = notifier_to_errno(err); 1640 if (err) 1641 return err; 1642 1643 if (!(dev->flags & IFF_UP)) 1644 return 0; 1645 1646 call_netdevice_notifier(nb, NETDEV_UP, dev); 1647 return 0; 1648 } 1649 1650 static void call_netdevice_unregister_notifiers(struct notifier_block *nb, 1651 struct net_device *dev) 1652 { 1653 if (dev->flags & IFF_UP) { 1654 call_netdevice_notifier(nb, NETDEV_GOING_DOWN, 1655 dev); 1656 call_netdevice_notifier(nb, NETDEV_DOWN, dev); 1657 } 1658 call_netdevice_notifier(nb, NETDEV_UNREGISTER, dev); 1659 } 1660 1661 static int call_netdevice_register_net_notifiers(struct notifier_block *nb, 1662 struct net *net) 1663 { 1664 struct net_device *dev; 1665 int err; 1666 1667 for_each_netdev(net, dev) { 1668 err = call_netdevice_register_notifiers(nb, dev); 1669 if (err) 1670 goto rollback; 1671 } 1672 return 0; 1673 1674 rollback: 1675 for_each_netdev_continue_reverse(net, dev) 1676 call_netdevice_unregister_notifiers(nb, dev); 1677 return err; 1678 } 1679 1680 static void call_netdevice_unregister_net_notifiers(struct notifier_block *nb, 1681 struct net *net) 1682 { 1683 struct net_device *dev; 1684 1685 for_each_netdev(net, dev) 1686 call_netdevice_unregister_notifiers(nb, dev); 1687 } 1688 1689 static int dev_boot_phase = 1; 1690 1691 /** 1692 * register_netdevice_notifier - register a network notifier block 1693 * @nb: notifier 1694 * 1695 * Register a notifier to be called when network device events occur. 1696 * The notifier passed is linked into the kernel structures and must 1697 * not be reused until it has been unregistered. A negative errno code 1698 * is returned on a failure. 1699 * 1700 * When registered all registration and up events are replayed 1701 * to the new notifier to allow device to have a race free 1702 * view of the network device list. 1703 */ 1704 1705 int register_netdevice_notifier(struct notifier_block *nb) 1706 { 1707 struct net *net; 1708 int err; 1709 1710 /* Close race with setup_net() and cleanup_net() */ 1711 down_write(&pernet_ops_rwsem); 1712 rtnl_lock(); 1713 err = raw_notifier_chain_register(&netdev_chain, nb); 1714 if (err) 1715 goto unlock; 1716 if (dev_boot_phase) 1717 goto unlock; 1718 for_each_net(net) { 1719 err = call_netdevice_register_net_notifiers(nb, net); 1720 if (err) 1721 goto rollback; 1722 } 1723 1724 unlock: 1725 rtnl_unlock(); 1726 up_write(&pernet_ops_rwsem); 1727 return err; 1728 1729 rollback: 1730 for_each_net_continue_reverse(net) 1731 call_netdevice_unregister_net_notifiers(nb, net); 1732 1733 raw_notifier_chain_unregister(&netdev_chain, nb); 1734 goto unlock; 1735 } 1736 EXPORT_SYMBOL(register_netdevice_notifier); 1737 1738 /** 1739 * unregister_netdevice_notifier - unregister a network notifier block 1740 * @nb: notifier 1741 * 1742 * Unregister a notifier previously registered by 1743 * register_netdevice_notifier(). The notifier is unlinked into the 1744 * kernel structures and may then be reused. A negative errno code 1745 * is returned on a failure. 1746 * 1747 * After unregistering unregister and down device events are synthesized 1748 * for all devices on the device list to the removed notifier to remove 1749 * the need for special case cleanup code. 1750 */ 1751 1752 int unregister_netdevice_notifier(struct notifier_block *nb) 1753 { 1754 struct net *net; 1755 int err; 1756 1757 /* Close race with setup_net() and cleanup_net() */ 1758 down_write(&pernet_ops_rwsem); 1759 rtnl_lock(); 1760 err = raw_notifier_chain_unregister(&netdev_chain, nb); 1761 if (err) 1762 goto unlock; 1763 1764 for_each_net(net) 1765 call_netdevice_unregister_net_notifiers(nb, net); 1766 1767 unlock: 1768 rtnl_unlock(); 1769 up_write(&pernet_ops_rwsem); 1770 return err; 1771 } 1772 EXPORT_SYMBOL(unregister_netdevice_notifier); 1773 1774 static int __register_netdevice_notifier_net(struct net *net, 1775 struct notifier_block *nb, 1776 bool ignore_call_fail) 1777 { 1778 int err; 1779 1780 err = raw_notifier_chain_register(&net->netdev_chain, nb); 1781 if (err) 1782 return err; 1783 if (dev_boot_phase) 1784 return 0; 1785 1786 err = call_netdevice_register_net_notifiers(nb, net); 1787 if (err && !ignore_call_fail) 1788 goto chain_unregister; 1789 1790 return 0; 1791 1792 chain_unregister: 1793 raw_notifier_chain_unregister(&net->netdev_chain, nb); 1794 return err; 1795 } 1796 1797 static int __unregister_netdevice_notifier_net(struct net *net, 1798 struct notifier_block *nb) 1799 { 1800 int err; 1801 1802 err = raw_notifier_chain_unregister(&net->netdev_chain, nb); 1803 if (err) 1804 return err; 1805 1806 call_netdevice_unregister_net_notifiers(nb, net); 1807 return 0; 1808 } 1809 1810 /** 1811 * register_netdevice_notifier_net - register a per-netns network notifier block 1812 * @net: network namespace 1813 * @nb: notifier 1814 * 1815 * Register a notifier to be called when network device events occur. 1816 * The notifier passed is linked into the kernel structures and must 1817 * not be reused until it has been unregistered. A negative errno code 1818 * is returned on a failure. 1819 * 1820 * When registered all registration and up events are replayed 1821 * to the new notifier to allow device to have a race free 1822 * view of the network device list. 1823 */ 1824 1825 int register_netdevice_notifier_net(struct net *net, struct notifier_block *nb) 1826 { 1827 int err; 1828 1829 rtnl_lock(); 1830 err = __register_netdevice_notifier_net(net, nb, false); 1831 rtnl_unlock(); 1832 return err; 1833 } 1834 EXPORT_SYMBOL(register_netdevice_notifier_net); 1835 1836 /** 1837 * unregister_netdevice_notifier_net - unregister a per-netns 1838 * network notifier block 1839 * @net: network namespace 1840 * @nb: notifier 1841 * 1842 * Unregister a notifier previously registered by 1843 * register_netdevice_notifier(). The notifier is unlinked into the 1844 * kernel structures and may then be reused. A negative errno code 1845 * is returned on a failure. 1846 * 1847 * After unregistering unregister and down device events are synthesized 1848 * for all devices on the device list to the removed notifier to remove 1849 * the need for special case cleanup code. 1850 */ 1851 1852 int unregister_netdevice_notifier_net(struct net *net, 1853 struct notifier_block *nb) 1854 { 1855 int err; 1856 1857 rtnl_lock(); 1858 err = __unregister_netdevice_notifier_net(net, nb); 1859 rtnl_unlock(); 1860 return err; 1861 } 1862 EXPORT_SYMBOL(unregister_netdevice_notifier_net); 1863 1864 static void __move_netdevice_notifier_net(struct net *src_net, 1865 struct net *dst_net, 1866 struct notifier_block *nb) 1867 { 1868 __unregister_netdevice_notifier_net(src_net, nb); 1869 __register_netdevice_notifier_net(dst_net, nb, true); 1870 } 1871 1872 void move_netdevice_notifier_net(struct net *src_net, struct net *dst_net, 1873 struct notifier_block *nb) 1874 { 1875 rtnl_lock(); 1876 __move_netdevice_notifier_net(src_net, dst_net, nb); 1877 rtnl_unlock(); 1878 } 1879 1880 int register_netdevice_notifier_dev_net(struct net_device *dev, 1881 struct notifier_block *nb, 1882 struct netdev_net_notifier *nn) 1883 { 1884 int err; 1885 1886 rtnl_lock(); 1887 err = __register_netdevice_notifier_net(dev_net(dev), nb, false); 1888 if (!err) { 1889 nn->nb = nb; 1890 list_add(&nn->list, &dev->net_notifier_list); 1891 } 1892 rtnl_unlock(); 1893 return err; 1894 } 1895 EXPORT_SYMBOL(register_netdevice_notifier_dev_net); 1896 1897 int unregister_netdevice_notifier_dev_net(struct net_device *dev, 1898 struct notifier_block *nb, 1899 struct netdev_net_notifier *nn) 1900 { 1901 int err; 1902 1903 rtnl_lock(); 1904 list_del(&nn->list); 1905 err = __unregister_netdevice_notifier_net(dev_net(dev), nb); 1906 rtnl_unlock(); 1907 return err; 1908 } 1909 EXPORT_SYMBOL(unregister_netdevice_notifier_dev_net); 1910 1911 static void move_netdevice_notifiers_dev_net(struct net_device *dev, 1912 struct net *net) 1913 { 1914 struct netdev_net_notifier *nn; 1915 1916 list_for_each_entry(nn, &dev->net_notifier_list, list) 1917 __move_netdevice_notifier_net(dev_net(dev), net, nn->nb); 1918 } 1919 1920 /** 1921 * call_netdevice_notifiers_info - call all network notifier blocks 1922 * @val: value passed unmodified to notifier function 1923 * @info: notifier information data 1924 * 1925 * Call all network notifier blocks. Parameters and return value 1926 * are as for raw_notifier_call_chain(). 1927 */ 1928 1929 static int call_netdevice_notifiers_info(unsigned long val, 1930 struct netdev_notifier_info *info) 1931 { 1932 struct net *net = dev_net(info->dev); 1933 int ret; 1934 1935 ASSERT_RTNL(); 1936 1937 /* Run per-netns notifier block chain first, then run the global one. 1938 * Hopefully, one day, the global one is going to be removed after 1939 * all notifier block registrators get converted to be per-netns. 1940 */ 1941 ret = raw_notifier_call_chain(&net->netdev_chain, val, info); 1942 if (ret & NOTIFY_STOP_MASK) 1943 return ret; 1944 return raw_notifier_call_chain(&netdev_chain, val, info); 1945 } 1946 1947 /** 1948 * call_netdevice_notifiers_info_robust - call per-netns notifier blocks 1949 * for and rollback on error 1950 * @val_up: value passed unmodified to notifier function 1951 * @val_down: value passed unmodified to the notifier function when 1952 * recovering from an error on @val_up 1953 * @info: notifier information data 1954 * 1955 * Call all per-netns network notifier blocks, but not notifier blocks on 1956 * the global notifier chain. Parameters and return value are as for 1957 * raw_notifier_call_chain_robust(). 1958 */ 1959 1960 static int 1961 call_netdevice_notifiers_info_robust(unsigned long val_up, 1962 unsigned long val_down, 1963 struct netdev_notifier_info *info) 1964 { 1965 struct net *net = dev_net(info->dev); 1966 1967 ASSERT_RTNL(); 1968 1969 return raw_notifier_call_chain_robust(&net->netdev_chain, 1970 val_up, val_down, info); 1971 } 1972 1973 static int call_netdevice_notifiers_extack(unsigned long val, 1974 struct net_device *dev, 1975 struct netlink_ext_ack *extack) 1976 { 1977 struct netdev_notifier_info info = { 1978 .dev = dev, 1979 .extack = extack, 1980 }; 1981 1982 return call_netdevice_notifiers_info(val, &info); 1983 } 1984 1985 /** 1986 * call_netdevice_notifiers - call all network notifier blocks 1987 * @val: value passed unmodified to notifier function 1988 * @dev: net_device pointer passed unmodified to notifier function 1989 * 1990 * Call all network notifier blocks. Parameters and return value 1991 * are as for raw_notifier_call_chain(). 1992 */ 1993 1994 int call_netdevice_notifiers(unsigned long val, struct net_device *dev) 1995 { 1996 return call_netdevice_notifiers_extack(val, dev, NULL); 1997 } 1998 EXPORT_SYMBOL(call_netdevice_notifiers); 1999 2000 /** 2001 * call_netdevice_notifiers_mtu - call all network notifier blocks 2002 * @val: value passed unmodified to notifier function 2003 * @dev: net_device pointer passed unmodified to notifier function 2004 * @arg: additional u32 argument passed to the notifier function 2005 * 2006 * Call all network notifier blocks. Parameters and return value 2007 * are as for raw_notifier_call_chain(). 2008 */ 2009 static int call_netdevice_notifiers_mtu(unsigned long val, 2010 struct net_device *dev, u32 arg) 2011 { 2012 struct netdev_notifier_info_ext info = { 2013 .info.dev = dev, 2014 .ext.mtu = arg, 2015 }; 2016 2017 BUILD_BUG_ON(offsetof(struct netdev_notifier_info_ext, info) != 0); 2018 2019 return call_netdevice_notifiers_info(val, &info.info); 2020 } 2021 2022 #ifdef CONFIG_NET_INGRESS 2023 static DEFINE_STATIC_KEY_FALSE(ingress_needed_key); 2024 2025 void net_inc_ingress_queue(void) 2026 { 2027 static_branch_inc(&ingress_needed_key); 2028 } 2029 EXPORT_SYMBOL_GPL(net_inc_ingress_queue); 2030 2031 void net_dec_ingress_queue(void) 2032 { 2033 static_branch_dec(&ingress_needed_key); 2034 } 2035 EXPORT_SYMBOL_GPL(net_dec_ingress_queue); 2036 #endif 2037 2038 #ifdef CONFIG_NET_EGRESS 2039 static DEFINE_STATIC_KEY_FALSE(egress_needed_key); 2040 2041 void net_inc_egress_queue(void) 2042 { 2043 static_branch_inc(&egress_needed_key); 2044 } 2045 EXPORT_SYMBOL_GPL(net_inc_egress_queue); 2046 2047 void net_dec_egress_queue(void) 2048 { 2049 static_branch_dec(&egress_needed_key); 2050 } 2051 EXPORT_SYMBOL_GPL(net_dec_egress_queue); 2052 #endif 2053 2054 DEFINE_STATIC_KEY_FALSE(netstamp_needed_key); 2055 EXPORT_SYMBOL(netstamp_needed_key); 2056 #ifdef CONFIG_JUMP_LABEL 2057 static atomic_t netstamp_needed_deferred; 2058 static atomic_t netstamp_wanted; 2059 static void netstamp_clear(struct work_struct *work) 2060 { 2061 int deferred = atomic_xchg(&netstamp_needed_deferred, 0); 2062 int wanted; 2063 2064 wanted = atomic_add_return(deferred, &netstamp_wanted); 2065 if (wanted > 0) 2066 static_branch_enable(&netstamp_needed_key); 2067 else 2068 static_branch_disable(&netstamp_needed_key); 2069 } 2070 static DECLARE_WORK(netstamp_work, netstamp_clear); 2071 #endif 2072 2073 void net_enable_timestamp(void) 2074 { 2075 #ifdef CONFIG_JUMP_LABEL 2076 int wanted; 2077 2078 while (1) { 2079 wanted = atomic_read(&netstamp_wanted); 2080 if (wanted <= 0) 2081 break; 2082 if (atomic_cmpxchg(&netstamp_wanted, wanted, wanted + 1) == wanted) 2083 return; 2084 } 2085 atomic_inc(&netstamp_needed_deferred); 2086 schedule_work(&netstamp_work); 2087 #else 2088 static_branch_inc(&netstamp_needed_key); 2089 #endif 2090 } 2091 EXPORT_SYMBOL(net_enable_timestamp); 2092 2093 void net_disable_timestamp(void) 2094 { 2095 #ifdef CONFIG_JUMP_LABEL 2096 int wanted; 2097 2098 while (1) { 2099 wanted = atomic_read(&netstamp_wanted); 2100 if (wanted <= 1) 2101 break; 2102 if (atomic_cmpxchg(&netstamp_wanted, wanted, wanted - 1) == wanted) 2103 return; 2104 } 2105 atomic_dec(&netstamp_needed_deferred); 2106 schedule_work(&netstamp_work); 2107 #else 2108 static_branch_dec(&netstamp_needed_key); 2109 #endif 2110 } 2111 EXPORT_SYMBOL(net_disable_timestamp); 2112 2113 static inline void net_timestamp_set(struct sk_buff *skb) 2114 { 2115 skb->tstamp = 0; 2116 skb->mono_delivery_time = 0; 2117 if (static_branch_unlikely(&netstamp_needed_key)) 2118 skb->tstamp = ktime_get_real(); 2119 } 2120 2121 #define net_timestamp_check(COND, SKB) \ 2122 if (static_branch_unlikely(&netstamp_needed_key)) { \ 2123 if ((COND) && !(SKB)->tstamp) \ 2124 (SKB)->tstamp = ktime_get_real(); \ 2125 } \ 2126 2127 bool is_skb_forwardable(const struct net_device *dev, const struct sk_buff *skb) 2128 { 2129 return __is_skb_forwardable(dev, skb, true); 2130 } 2131 EXPORT_SYMBOL_GPL(is_skb_forwardable); 2132 2133 static int __dev_forward_skb2(struct net_device *dev, struct sk_buff *skb, 2134 bool check_mtu) 2135 { 2136 int ret = ____dev_forward_skb(dev, skb, check_mtu); 2137 2138 if (likely(!ret)) { 2139 skb->protocol = eth_type_trans(skb, dev); 2140 skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN); 2141 } 2142 2143 return ret; 2144 } 2145 2146 int __dev_forward_skb(struct net_device *dev, struct sk_buff *skb) 2147 { 2148 return __dev_forward_skb2(dev, skb, true); 2149 } 2150 EXPORT_SYMBOL_GPL(__dev_forward_skb); 2151 2152 /** 2153 * dev_forward_skb - loopback an skb to another netif 2154 * 2155 * @dev: destination network device 2156 * @skb: buffer to forward 2157 * 2158 * return values: 2159 * NET_RX_SUCCESS (no congestion) 2160 * NET_RX_DROP (packet was dropped, but freed) 2161 * 2162 * dev_forward_skb can be used for injecting an skb from the 2163 * start_xmit function of one device into the receive queue 2164 * of another device. 2165 * 2166 * The receiving device may be in another namespace, so 2167 * we have to clear all information in the skb that could 2168 * impact namespace isolation. 2169 */ 2170 int dev_forward_skb(struct net_device *dev, struct sk_buff *skb) 2171 { 2172 return __dev_forward_skb(dev, skb) ?: netif_rx_internal(skb); 2173 } 2174 EXPORT_SYMBOL_GPL(dev_forward_skb); 2175 2176 int dev_forward_skb_nomtu(struct net_device *dev, struct sk_buff *skb) 2177 { 2178 return __dev_forward_skb2(dev, skb, false) ?: netif_rx_internal(skb); 2179 } 2180 2181 static inline int deliver_skb(struct sk_buff *skb, 2182 struct packet_type *pt_prev, 2183 struct net_device *orig_dev) 2184 { 2185 if (unlikely(skb_orphan_frags_rx(skb, GFP_ATOMIC))) 2186 return -ENOMEM; 2187 refcount_inc(&skb->users); 2188 return pt_prev->func(skb, skb->dev, pt_prev, orig_dev); 2189 } 2190 2191 static inline void deliver_ptype_list_skb(struct sk_buff *skb, 2192 struct packet_type **pt, 2193 struct net_device *orig_dev, 2194 __be16 type, 2195 struct list_head *ptype_list) 2196 { 2197 struct packet_type *ptype, *pt_prev = *pt; 2198 2199 list_for_each_entry_rcu(ptype, ptype_list, list) { 2200 if (ptype->type != type) 2201 continue; 2202 if (pt_prev) 2203 deliver_skb(skb, pt_prev, orig_dev); 2204 pt_prev = ptype; 2205 } 2206 *pt = pt_prev; 2207 } 2208 2209 static inline bool skb_loop_sk(struct packet_type *ptype, struct sk_buff *skb) 2210 { 2211 if (!ptype->af_packet_priv || !skb->sk) 2212 return false; 2213 2214 if (ptype->id_match) 2215 return ptype->id_match(ptype, skb->sk); 2216 else if ((struct sock *)ptype->af_packet_priv == skb->sk) 2217 return true; 2218 2219 return false; 2220 } 2221 2222 /** 2223 * dev_nit_active - return true if any network interface taps are in use 2224 * 2225 * @dev: network device to check for the presence of taps 2226 */ 2227 bool dev_nit_active(struct net_device *dev) 2228 { 2229 return !list_empty(&ptype_all) || !list_empty(&dev->ptype_all); 2230 } 2231 EXPORT_SYMBOL_GPL(dev_nit_active); 2232 2233 /* 2234 * Support routine. Sends outgoing frames to any network 2235 * taps currently in use. 2236 */ 2237 2238 void dev_queue_xmit_nit(struct sk_buff *skb, struct net_device *dev) 2239 { 2240 struct packet_type *ptype; 2241 struct sk_buff *skb2 = NULL; 2242 struct packet_type *pt_prev = NULL; 2243 struct list_head *ptype_list = &ptype_all; 2244 2245 rcu_read_lock(); 2246 again: 2247 list_for_each_entry_rcu(ptype, ptype_list, list) { 2248 if (ptype->ignore_outgoing) 2249 continue; 2250 2251 /* Never send packets back to the socket 2252 * they originated from - MvS (miquels@drinkel.ow.org) 2253 */ 2254 if (skb_loop_sk(ptype, skb)) 2255 continue; 2256 2257 if (pt_prev) { 2258 deliver_skb(skb2, pt_prev, skb->dev); 2259 pt_prev = ptype; 2260 continue; 2261 } 2262 2263 /* need to clone skb, done only once */ 2264 skb2 = skb_clone(skb, GFP_ATOMIC); 2265 if (!skb2) 2266 goto out_unlock; 2267 2268 net_timestamp_set(skb2); 2269 2270 /* skb->nh should be correctly 2271 * set by sender, so that the second statement is 2272 * just protection against buggy protocols. 2273 */ 2274 skb_reset_mac_header(skb2); 2275 2276 if (skb_network_header(skb2) < skb2->data || 2277 skb_network_header(skb2) > skb_tail_pointer(skb2)) { 2278 net_crit_ratelimited("protocol %04x is buggy, dev %s\n", 2279 ntohs(skb2->protocol), 2280 dev->name); 2281 skb_reset_network_header(skb2); 2282 } 2283 2284 skb2->transport_header = skb2->network_header; 2285 skb2->pkt_type = PACKET_OUTGOING; 2286 pt_prev = ptype; 2287 } 2288 2289 if (ptype_list == &ptype_all) { 2290 ptype_list = &dev->ptype_all; 2291 goto again; 2292 } 2293 out_unlock: 2294 if (pt_prev) { 2295 if (!skb_orphan_frags_rx(skb2, GFP_ATOMIC)) 2296 pt_prev->func(skb2, skb->dev, pt_prev, skb->dev); 2297 else 2298 kfree_skb(skb2); 2299 } 2300 rcu_read_unlock(); 2301 } 2302 EXPORT_SYMBOL_GPL(dev_queue_xmit_nit); 2303 2304 /** 2305 * netif_setup_tc - Handle tc mappings on real_num_tx_queues change 2306 * @dev: Network device 2307 * @txq: number of queues available 2308 * 2309 * If real_num_tx_queues is changed the tc mappings may no longer be 2310 * valid. To resolve this verify the tc mapping remains valid and if 2311 * not NULL the mapping. With no priorities mapping to this 2312 * offset/count pair it will no longer be used. In the worst case TC0 2313 * is invalid nothing can be done so disable priority mappings. If is 2314 * expected that drivers will fix this mapping if they can before 2315 * calling netif_set_real_num_tx_queues. 2316 */ 2317 static void netif_setup_tc(struct net_device *dev, unsigned int txq) 2318 { 2319 int i; 2320 struct netdev_tc_txq *tc = &dev->tc_to_txq[0]; 2321 2322 /* If TC0 is invalidated disable TC mapping */ 2323 if (tc->offset + tc->count > txq) { 2324 netdev_warn(dev, "Number of in use tx queues changed invalidating tc mappings. Priority traffic classification disabled!\n"); 2325 dev->num_tc = 0; 2326 return; 2327 } 2328 2329 /* Invalidated prio to tc mappings set to TC0 */ 2330 for (i = 1; i < TC_BITMASK + 1; i++) { 2331 int q = netdev_get_prio_tc_map(dev, i); 2332 2333 tc = &dev->tc_to_txq[q]; 2334 if (tc->offset + tc->count > txq) { 2335 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", 2336 i, q); 2337 netdev_set_prio_tc_map(dev, i, 0); 2338 } 2339 } 2340 } 2341 2342 int netdev_txq_to_tc(struct net_device *dev, unsigned int txq) 2343 { 2344 if (dev->num_tc) { 2345 struct netdev_tc_txq *tc = &dev->tc_to_txq[0]; 2346 int i; 2347 2348 /* walk through the TCs and see if it falls into any of them */ 2349 for (i = 0; i < TC_MAX_QUEUE; i++, tc++) { 2350 if ((txq - tc->offset) < tc->count) 2351 return i; 2352 } 2353 2354 /* didn't find it, just return -1 to indicate no match */ 2355 return -1; 2356 } 2357 2358 return 0; 2359 } 2360 EXPORT_SYMBOL(netdev_txq_to_tc); 2361 2362 #ifdef CONFIG_XPS 2363 static struct static_key xps_needed __read_mostly; 2364 static struct static_key xps_rxqs_needed __read_mostly; 2365 static DEFINE_MUTEX(xps_map_mutex); 2366 #define xmap_dereference(P) \ 2367 rcu_dereference_protected((P), lockdep_is_held(&xps_map_mutex)) 2368 2369 static bool remove_xps_queue(struct xps_dev_maps *dev_maps, 2370 struct xps_dev_maps *old_maps, int tci, u16 index) 2371 { 2372 struct xps_map *map = NULL; 2373 int pos; 2374 2375 if (dev_maps) 2376 map = xmap_dereference(dev_maps->attr_map[tci]); 2377 if (!map) 2378 return false; 2379 2380 for (pos = map->len; pos--;) { 2381 if (map->queues[pos] != index) 2382 continue; 2383 2384 if (map->len > 1) { 2385 map->queues[pos] = map->queues[--map->len]; 2386 break; 2387 } 2388 2389 if (old_maps) 2390 RCU_INIT_POINTER(old_maps->attr_map[tci], NULL); 2391 RCU_INIT_POINTER(dev_maps->attr_map[tci], NULL); 2392 kfree_rcu(map, rcu); 2393 return false; 2394 } 2395 2396 return true; 2397 } 2398 2399 static bool remove_xps_queue_cpu(struct net_device *dev, 2400 struct xps_dev_maps *dev_maps, 2401 int cpu, u16 offset, u16 count) 2402 { 2403 int num_tc = dev_maps->num_tc; 2404 bool active = false; 2405 int tci; 2406 2407 for (tci = cpu * num_tc; num_tc--; tci++) { 2408 int i, j; 2409 2410 for (i = count, j = offset; i--; j++) { 2411 if (!remove_xps_queue(dev_maps, NULL, tci, j)) 2412 break; 2413 } 2414 2415 active |= i < 0; 2416 } 2417 2418 return active; 2419 } 2420 2421 static void reset_xps_maps(struct net_device *dev, 2422 struct xps_dev_maps *dev_maps, 2423 enum xps_map_type type) 2424 { 2425 static_key_slow_dec_cpuslocked(&xps_needed); 2426 if (type == XPS_RXQS) 2427 static_key_slow_dec_cpuslocked(&xps_rxqs_needed); 2428 2429 RCU_INIT_POINTER(dev->xps_maps[type], NULL); 2430 2431 kfree_rcu(dev_maps, rcu); 2432 } 2433 2434 static void clean_xps_maps(struct net_device *dev, enum xps_map_type type, 2435 u16 offset, u16 count) 2436 { 2437 struct xps_dev_maps *dev_maps; 2438 bool active = false; 2439 int i, j; 2440 2441 dev_maps = xmap_dereference(dev->xps_maps[type]); 2442 if (!dev_maps) 2443 return; 2444 2445 for (j = 0; j < dev_maps->nr_ids; j++) 2446 active |= remove_xps_queue_cpu(dev, dev_maps, j, offset, count); 2447 if (!active) 2448 reset_xps_maps(dev, dev_maps, type); 2449 2450 if (type == XPS_CPUS) { 2451 for (i = offset + (count - 1); count--; i--) 2452 netdev_queue_numa_node_write( 2453 netdev_get_tx_queue(dev, i), NUMA_NO_NODE); 2454 } 2455 } 2456 2457 static void netif_reset_xps_queues(struct net_device *dev, u16 offset, 2458 u16 count) 2459 { 2460 if (!static_key_false(&xps_needed)) 2461 return; 2462 2463 cpus_read_lock(); 2464 mutex_lock(&xps_map_mutex); 2465 2466 if (static_key_false(&xps_rxqs_needed)) 2467 clean_xps_maps(dev, XPS_RXQS, offset, count); 2468 2469 clean_xps_maps(dev, XPS_CPUS, offset, count); 2470 2471 mutex_unlock(&xps_map_mutex); 2472 cpus_read_unlock(); 2473 } 2474 2475 static void netif_reset_xps_queues_gt(struct net_device *dev, u16 index) 2476 { 2477 netif_reset_xps_queues(dev, index, dev->num_tx_queues - index); 2478 } 2479 2480 static struct xps_map *expand_xps_map(struct xps_map *map, int attr_index, 2481 u16 index, bool is_rxqs_map) 2482 { 2483 struct xps_map *new_map; 2484 int alloc_len = XPS_MIN_MAP_ALLOC; 2485 int i, pos; 2486 2487 for (pos = 0; map && pos < map->len; pos++) { 2488 if (map->queues[pos] != index) 2489 continue; 2490 return map; 2491 } 2492 2493 /* Need to add tx-queue to this CPU's/rx-queue's existing map */ 2494 if (map) { 2495 if (pos < map->alloc_len) 2496 return map; 2497 2498 alloc_len = map->alloc_len * 2; 2499 } 2500 2501 /* Need to allocate new map to store tx-queue on this CPU's/rx-queue's 2502 * map 2503 */ 2504 if (is_rxqs_map) 2505 new_map = kzalloc(XPS_MAP_SIZE(alloc_len), GFP_KERNEL); 2506 else 2507 new_map = kzalloc_node(XPS_MAP_SIZE(alloc_len), GFP_KERNEL, 2508 cpu_to_node(attr_index)); 2509 if (!new_map) 2510 return NULL; 2511 2512 for (i = 0; i < pos; i++) 2513 new_map->queues[i] = map->queues[i]; 2514 new_map->alloc_len = alloc_len; 2515 new_map->len = pos; 2516 2517 return new_map; 2518 } 2519 2520 /* Copy xps maps at a given index */ 2521 static void xps_copy_dev_maps(struct xps_dev_maps *dev_maps, 2522 struct xps_dev_maps *new_dev_maps, int index, 2523 int tc, bool skip_tc) 2524 { 2525 int i, tci = index * dev_maps->num_tc; 2526 struct xps_map *map; 2527 2528 /* copy maps belonging to foreign traffic classes */ 2529 for (i = 0; i < dev_maps->num_tc; i++, tci++) { 2530 if (i == tc && skip_tc) 2531 continue; 2532 2533 /* fill in the new device map from the old device map */ 2534 map = xmap_dereference(dev_maps->attr_map[tci]); 2535 RCU_INIT_POINTER(new_dev_maps->attr_map[tci], map); 2536 } 2537 } 2538 2539 /* Must be called under cpus_read_lock */ 2540 int __netif_set_xps_queue(struct net_device *dev, const unsigned long *mask, 2541 u16 index, enum xps_map_type type) 2542 { 2543 struct xps_dev_maps *dev_maps, *new_dev_maps = NULL, *old_dev_maps = NULL; 2544 const unsigned long *online_mask = NULL; 2545 bool active = false, copy = false; 2546 int i, j, tci, numa_node_id = -2; 2547 int maps_sz, num_tc = 1, tc = 0; 2548 struct xps_map *map, *new_map; 2549 unsigned int nr_ids; 2550 2551 if (dev->num_tc) { 2552 /* Do not allow XPS on subordinate device directly */ 2553 num_tc = dev->num_tc; 2554 if (num_tc < 0) 2555 return -EINVAL; 2556 2557 /* If queue belongs to subordinate dev use its map */ 2558 dev = netdev_get_tx_queue(dev, index)->sb_dev ? : dev; 2559 2560 tc = netdev_txq_to_tc(dev, index); 2561 if (tc < 0) 2562 return -EINVAL; 2563 } 2564 2565 mutex_lock(&xps_map_mutex); 2566 2567 dev_maps = xmap_dereference(dev->xps_maps[type]); 2568 if (type == XPS_RXQS) { 2569 maps_sz = XPS_RXQ_DEV_MAPS_SIZE(num_tc, dev->num_rx_queues); 2570 nr_ids = dev->num_rx_queues; 2571 } else { 2572 maps_sz = XPS_CPU_DEV_MAPS_SIZE(num_tc); 2573 if (num_possible_cpus() > 1) 2574 online_mask = cpumask_bits(cpu_online_mask); 2575 nr_ids = nr_cpu_ids; 2576 } 2577 2578 if (maps_sz < L1_CACHE_BYTES) 2579 maps_sz = L1_CACHE_BYTES; 2580 2581 /* The old dev_maps could be larger or smaller than the one we're 2582 * setting up now, as dev->num_tc or nr_ids could have been updated in 2583 * between. We could try to be smart, but let's be safe instead and only 2584 * copy foreign traffic classes if the two map sizes match. 2585 */ 2586 if (dev_maps && 2587 dev_maps->num_tc == num_tc && dev_maps->nr_ids == nr_ids) 2588 copy = true; 2589 2590 /* allocate memory for queue storage */ 2591 for (j = -1; j = netif_attrmask_next_and(j, online_mask, mask, nr_ids), 2592 j < nr_ids;) { 2593 if (!new_dev_maps) { 2594 new_dev_maps = kzalloc(maps_sz, GFP_KERNEL); 2595 if (!new_dev_maps) { 2596 mutex_unlock(&xps_map_mutex); 2597 return -ENOMEM; 2598 } 2599 2600 new_dev_maps->nr_ids = nr_ids; 2601 new_dev_maps->num_tc = num_tc; 2602 } 2603 2604 tci = j * num_tc + tc; 2605 map = copy ? xmap_dereference(dev_maps->attr_map[tci]) : NULL; 2606 2607 map = expand_xps_map(map, j, index, type == XPS_RXQS); 2608 if (!map) 2609 goto error; 2610 2611 RCU_INIT_POINTER(new_dev_maps->attr_map[tci], map); 2612 } 2613 2614 if (!new_dev_maps) 2615 goto out_no_new_maps; 2616 2617 if (!dev_maps) { 2618 /* Increment static keys at most once per type */ 2619 static_key_slow_inc_cpuslocked(&xps_needed); 2620 if (type == XPS_RXQS) 2621 static_key_slow_inc_cpuslocked(&xps_rxqs_needed); 2622 } 2623 2624 for (j = 0; j < nr_ids; j++) { 2625 bool skip_tc = false; 2626 2627 tci = j * num_tc + tc; 2628 if (netif_attr_test_mask(j, mask, nr_ids) && 2629 netif_attr_test_online(j, online_mask, nr_ids)) { 2630 /* add tx-queue to CPU/rx-queue maps */ 2631 int pos = 0; 2632 2633 skip_tc = true; 2634 2635 map = xmap_dereference(new_dev_maps->attr_map[tci]); 2636 while ((pos < map->len) && (map->queues[pos] != index)) 2637 pos++; 2638 2639 if (pos == map->len) 2640 map->queues[map->len++] = index; 2641 #ifdef CONFIG_NUMA 2642 if (type == XPS_CPUS) { 2643 if (numa_node_id == -2) 2644 numa_node_id = cpu_to_node(j); 2645 else if (numa_node_id != cpu_to_node(j)) 2646 numa_node_id = -1; 2647 } 2648 #endif 2649 } 2650 2651 if (copy) 2652 xps_copy_dev_maps(dev_maps, new_dev_maps, j, tc, 2653 skip_tc); 2654 } 2655 2656 rcu_assign_pointer(dev->xps_maps[type], new_dev_maps); 2657 2658 /* Cleanup old maps */ 2659 if (!dev_maps) 2660 goto out_no_old_maps; 2661 2662 for (j = 0; j < dev_maps->nr_ids; j++) { 2663 for (i = num_tc, tci = j * dev_maps->num_tc; i--; tci++) { 2664 map = xmap_dereference(dev_maps->attr_map[tci]); 2665 if (!map) 2666 continue; 2667 2668 if (copy) { 2669 new_map = xmap_dereference(new_dev_maps->attr_map[tci]); 2670 if (map == new_map) 2671 continue; 2672 } 2673 2674 RCU_INIT_POINTER(dev_maps->attr_map[tci], NULL); 2675 kfree_rcu(map, rcu); 2676 } 2677 } 2678 2679 old_dev_maps = dev_maps; 2680 2681 out_no_old_maps: 2682 dev_maps = new_dev_maps; 2683 active = true; 2684 2685 out_no_new_maps: 2686 if (type == XPS_CPUS) 2687 /* update Tx queue numa node */ 2688 netdev_queue_numa_node_write(netdev_get_tx_queue(dev, index), 2689 (numa_node_id >= 0) ? 2690 numa_node_id : NUMA_NO_NODE); 2691 2692 if (!dev_maps) 2693 goto out_no_maps; 2694 2695 /* removes tx-queue from unused CPUs/rx-queues */ 2696 for (j = 0; j < dev_maps->nr_ids; j++) { 2697 tci = j * dev_maps->num_tc; 2698 2699 for (i = 0; i < dev_maps->num_tc; i++, tci++) { 2700 if (i == tc && 2701 netif_attr_test_mask(j, mask, dev_maps->nr_ids) && 2702 netif_attr_test_online(j, online_mask, dev_maps->nr_ids)) 2703 continue; 2704 2705 active |= remove_xps_queue(dev_maps, 2706 copy ? old_dev_maps : NULL, 2707 tci, index); 2708 } 2709 } 2710 2711 if (old_dev_maps) 2712 kfree_rcu(old_dev_maps, rcu); 2713 2714 /* free map if not active */ 2715 if (!active) 2716 reset_xps_maps(dev, dev_maps, type); 2717 2718 out_no_maps: 2719 mutex_unlock(&xps_map_mutex); 2720 2721 return 0; 2722 error: 2723 /* remove any maps that we added */ 2724 for (j = 0; j < nr_ids; j++) { 2725 for (i = num_tc, tci = j * num_tc; i--; tci++) { 2726 new_map = xmap_dereference(new_dev_maps->attr_map[tci]); 2727 map = copy ? 2728 xmap_dereference(dev_maps->attr_map[tci]) : 2729 NULL; 2730 if (new_map && new_map != map) 2731 kfree(new_map); 2732 } 2733 } 2734 2735 mutex_unlock(&xps_map_mutex); 2736 2737 kfree(new_dev_maps); 2738 return -ENOMEM; 2739 } 2740 EXPORT_SYMBOL_GPL(__netif_set_xps_queue); 2741 2742 int netif_set_xps_queue(struct net_device *dev, const struct cpumask *mask, 2743 u16 index) 2744 { 2745 int ret; 2746 2747 cpus_read_lock(); 2748 ret = __netif_set_xps_queue(dev, cpumask_bits(mask), index, XPS_CPUS); 2749 cpus_read_unlock(); 2750 2751 return ret; 2752 } 2753 EXPORT_SYMBOL(netif_set_xps_queue); 2754 2755 #endif 2756 static void netdev_unbind_all_sb_channels(struct net_device *dev) 2757 { 2758 struct netdev_queue *txq = &dev->_tx[dev->num_tx_queues]; 2759 2760 /* Unbind any subordinate channels */ 2761 while (txq-- != &dev->_tx[0]) { 2762 if (txq->sb_dev) 2763 netdev_unbind_sb_channel(dev, txq->sb_dev); 2764 } 2765 } 2766 2767 void netdev_reset_tc(struct net_device *dev) 2768 { 2769 #ifdef CONFIG_XPS 2770 netif_reset_xps_queues_gt(dev, 0); 2771 #endif 2772 netdev_unbind_all_sb_channels(dev); 2773 2774 /* Reset TC configuration of device */ 2775 dev->num_tc = 0; 2776 memset(dev->tc_to_txq, 0, sizeof(dev->tc_to_txq)); 2777 memset(dev->prio_tc_map, 0, sizeof(dev->prio_tc_map)); 2778 } 2779 EXPORT_SYMBOL(netdev_reset_tc); 2780 2781 int netdev_set_tc_queue(struct net_device *dev, u8 tc, u16 count, u16 offset) 2782 { 2783 if (tc >= dev->num_tc) 2784 return -EINVAL; 2785 2786 #ifdef CONFIG_XPS 2787 netif_reset_xps_queues(dev, offset, count); 2788 #endif 2789 dev->tc_to_txq[tc].count = count; 2790 dev->tc_to_txq[tc].offset = offset; 2791 return 0; 2792 } 2793 EXPORT_SYMBOL(netdev_set_tc_queue); 2794 2795 int netdev_set_num_tc(struct net_device *dev, u8 num_tc) 2796 { 2797 if (num_tc > TC_MAX_QUEUE) 2798 return -EINVAL; 2799 2800 #ifdef CONFIG_XPS 2801 netif_reset_xps_queues_gt(dev, 0); 2802 #endif 2803 netdev_unbind_all_sb_channels(dev); 2804 2805 dev->num_tc = num_tc; 2806 return 0; 2807 } 2808 EXPORT_SYMBOL(netdev_set_num_tc); 2809 2810 void netdev_unbind_sb_channel(struct net_device *dev, 2811 struct net_device *sb_dev) 2812 { 2813 struct netdev_queue *txq = &dev->_tx[dev->num_tx_queues]; 2814 2815 #ifdef CONFIG_XPS 2816 netif_reset_xps_queues_gt(sb_dev, 0); 2817 #endif 2818 memset(sb_dev->tc_to_txq, 0, sizeof(sb_dev->tc_to_txq)); 2819 memset(sb_dev->prio_tc_map, 0, sizeof(sb_dev->prio_tc_map)); 2820 2821 while (txq-- != &dev->_tx[0]) { 2822 if (txq->sb_dev == sb_dev) 2823 txq->sb_dev = NULL; 2824 } 2825 } 2826 EXPORT_SYMBOL(netdev_unbind_sb_channel); 2827 2828 int netdev_bind_sb_channel_queue(struct net_device *dev, 2829 struct net_device *sb_dev, 2830 u8 tc, u16 count, u16 offset) 2831 { 2832 /* Make certain the sb_dev and dev are already configured */ 2833 if (sb_dev->num_tc >= 0 || tc >= dev->num_tc) 2834 return -EINVAL; 2835 2836 /* We cannot hand out queues we don't have */ 2837 if ((offset + count) > dev->real_num_tx_queues) 2838 return -EINVAL; 2839 2840 /* Record the mapping */ 2841 sb_dev->tc_to_txq[tc].count = count; 2842 sb_dev->tc_to_txq[tc].offset = offset; 2843 2844 /* Provide a way for Tx queue to find the tc_to_txq map or 2845 * XPS map for itself. 2846 */ 2847 while (count--) 2848 netdev_get_tx_queue(dev, count + offset)->sb_dev = sb_dev; 2849 2850 return 0; 2851 } 2852 EXPORT_SYMBOL(netdev_bind_sb_channel_queue); 2853 2854 int netdev_set_sb_channel(struct net_device *dev, u16 channel) 2855 { 2856 /* Do not use a multiqueue device to represent a subordinate channel */ 2857 if (netif_is_multiqueue(dev)) 2858 return -ENODEV; 2859 2860 /* We allow channels 1 - 32767 to be used for subordinate channels. 2861 * Channel 0 is meant to be "native" mode and used only to represent 2862 * the main root device. We allow writing 0 to reset the device back 2863 * to normal mode after being used as a subordinate channel. 2864 */ 2865 if (channel > S16_MAX) 2866 return -EINVAL; 2867 2868 dev->num_tc = -channel; 2869 2870 return 0; 2871 } 2872 EXPORT_SYMBOL(netdev_set_sb_channel); 2873 2874 /* 2875 * Routine to help set real_num_tx_queues. To avoid skbs mapped to queues 2876 * greater than real_num_tx_queues stale skbs on the qdisc must be flushed. 2877 */ 2878 int netif_set_real_num_tx_queues(struct net_device *dev, unsigned int txq) 2879 { 2880 bool disabling; 2881 int rc; 2882 2883 disabling = txq < dev->real_num_tx_queues; 2884 2885 if (txq < 1 || txq > dev->num_tx_queues) 2886 return -EINVAL; 2887 2888 if (dev->reg_state == NETREG_REGISTERED || 2889 dev->reg_state == NETREG_UNREGISTERING) { 2890 ASSERT_RTNL(); 2891 2892 rc = netdev_queue_update_kobjects(dev, dev->real_num_tx_queues, 2893 txq); 2894 if (rc) 2895 return rc; 2896 2897 if (dev->num_tc) 2898 netif_setup_tc(dev, txq); 2899 2900 dev_qdisc_change_real_num_tx(dev, txq); 2901 2902 dev->real_num_tx_queues = txq; 2903 2904 if (disabling) { 2905 synchronize_net(); 2906 qdisc_reset_all_tx_gt(dev, txq); 2907 #ifdef CONFIG_XPS 2908 netif_reset_xps_queues_gt(dev, txq); 2909 #endif 2910 } 2911 } else { 2912 dev->real_num_tx_queues = txq; 2913 } 2914 2915 return 0; 2916 } 2917 EXPORT_SYMBOL(netif_set_real_num_tx_queues); 2918 2919 #ifdef CONFIG_SYSFS 2920 /** 2921 * netif_set_real_num_rx_queues - set actual number of RX queues used 2922 * @dev: Network device 2923 * @rxq: Actual number of RX queues 2924 * 2925 * This must be called either with the rtnl_lock held or before 2926 * registration of the net device. Returns 0 on success, or a 2927 * negative error code. If called before registration, it always 2928 * succeeds. 2929 */ 2930 int netif_set_real_num_rx_queues(struct net_device *dev, unsigned int rxq) 2931 { 2932 int rc; 2933 2934 if (rxq < 1 || rxq > dev->num_rx_queues) 2935 return -EINVAL; 2936 2937 if (dev->reg_state == NETREG_REGISTERED) { 2938 ASSERT_RTNL(); 2939 2940 rc = net_rx_queue_update_kobjects(dev, dev->real_num_rx_queues, 2941 rxq); 2942 if (rc) 2943 return rc; 2944 } 2945 2946 dev->real_num_rx_queues = rxq; 2947 return 0; 2948 } 2949 EXPORT_SYMBOL(netif_set_real_num_rx_queues); 2950 #endif 2951 2952 /** 2953 * netif_set_real_num_queues - set actual number of RX and TX queues used 2954 * @dev: Network device 2955 * @txq: Actual number of TX queues 2956 * @rxq: Actual number of RX queues 2957 * 2958 * Set the real number of both TX and RX queues. 2959 * Does nothing if the number of queues is already correct. 2960 */ 2961 int netif_set_real_num_queues(struct net_device *dev, 2962 unsigned int txq, unsigned int rxq) 2963 { 2964 unsigned int old_rxq = dev->real_num_rx_queues; 2965 int err; 2966 2967 if (txq < 1 || txq > dev->num_tx_queues || 2968 rxq < 1 || rxq > dev->num_rx_queues) 2969 return -EINVAL; 2970 2971 /* Start from increases, so the error path only does decreases - 2972 * decreases can't fail. 2973 */ 2974 if (rxq > dev->real_num_rx_queues) { 2975 err = netif_set_real_num_rx_queues(dev, rxq); 2976 if (err) 2977 return err; 2978 } 2979 if (txq > dev->real_num_tx_queues) { 2980 err = netif_set_real_num_tx_queues(dev, txq); 2981 if (err) 2982 goto undo_rx; 2983 } 2984 if (rxq < dev->real_num_rx_queues) 2985 WARN_ON(netif_set_real_num_rx_queues(dev, rxq)); 2986 if (txq < dev->real_num_tx_queues) 2987 WARN_ON(netif_set_real_num_tx_queues(dev, txq)); 2988 2989 return 0; 2990 undo_rx: 2991 WARN_ON(netif_set_real_num_rx_queues(dev, old_rxq)); 2992 return err; 2993 } 2994 EXPORT_SYMBOL(netif_set_real_num_queues); 2995 2996 /** 2997 * netif_set_tso_max_size() - set the max size of TSO frames supported 2998 * @dev: netdev to update 2999 * @size: max skb->len of a TSO frame 3000 * 3001 * Set the limit on the size of TSO super-frames the device can handle. 3002 * Unless explicitly set the stack will assume the value of 3003 * %GSO_LEGACY_MAX_SIZE. 3004 */ 3005 void netif_set_tso_max_size(struct net_device *dev, unsigned int size) 3006 { 3007 dev->tso_max_size = min(GSO_MAX_SIZE, size); 3008 if (size < READ_ONCE(dev->gso_max_size)) 3009 netif_set_gso_max_size(dev, size); 3010 } 3011 EXPORT_SYMBOL(netif_set_tso_max_size); 3012 3013 /** 3014 * netif_set_tso_max_segs() - set the max number of segs supported for TSO 3015 * @dev: netdev to update 3016 * @segs: max number of TCP segments 3017 * 3018 * Set the limit on the number of TCP segments the device can generate from 3019 * a single TSO super-frame. 3020 * Unless explicitly set the stack will assume the value of %GSO_MAX_SEGS. 3021 */ 3022 void netif_set_tso_max_segs(struct net_device *dev, unsigned int segs) 3023 { 3024 dev->tso_max_segs = segs; 3025 if (segs < READ_ONCE(dev->gso_max_segs)) 3026 netif_set_gso_max_segs(dev, segs); 3027 } 3028 EXPORT_SYMBOL(netif_set_tso_max_segs); 3029 3030 /** 3031 * netif_inherit_tso_max() - copy all TSO limits from a lower device to an upper 3032 * @to: netdev to update 3033 * @from: netdev from which to copy the limits 3034 */ 3035 void netif_inherit_tso_max(struct net_device *to, const struct net_device *from) 3036 { 3037 netif_set_tso_max_size(to, from->tso_max_size); 3038 netif_set_tso_max_segs(to, from->tso_max_segs); 3039 } 3040 EXPORT_SYMBOL(netif_inherit_tso_max); 3041 3042 /** 3043 * netif_get_num_default_rss_queues - default number of RSS queues 3044 * 3045 * Default value is the number of physical cores if there are only 1 or 2, or 3046 * divided by 2 if there are more. 3047 */ 3048 int netif_get_num_default_rss_queues(void) 3049 { 3050 cpumask_var_t cpus; 3051 int cpu, count = 0; 3052 3053 if (unlikely(is_kdump_kernel() || !zalloc_cpumask_var(&cpus, GFP_KERNEL))) 3054 return 1; 3055 3056 cpumask_copy(cpus, cpu_online_mask); 3057 for_each_cpu(cpu, cpus) { 3058 ++count; 3059 cpumask_andnot(cpus, cpus, topology_sibling_cpumask(cpu)); 3060 } 3061 free_cpumask_var(cpus); 3062 3063 return count > 2 ? DIV_ROUND_UP(count, 2) : count; 3064 } 3065 EXPORT_SYMBOL(netif_get_num_default_rss_queues); 3066 3067 static void __netif_reschedule(struct Qdisc *q) 3068 { 3069 struct softnet_data *sd; 3070 unsigned long flags; 3071 3072 local_irq_save(flags); 3073 sd = this_cpu_ptr(&softnet_data); 3074 q->next_sched = NULL; 3075 *sd->output_queue_tailp = q; 3076 sd->output_queue_tailp = &q->next_sched; 3077 raise_softirq_irqoff(NET_TX_SOFTIRQ); 3078 local_irq_restore(flags); 3079 } 3080 3081 void __netif_schedule(struct Qdisc *q) 3082 { 3083 if (!test_and_set_bit(__QDISC_STATE_SCHED, &q->state)) 3084 __netif_reschedule(q); 3085 } 3086 EXPORT_SYMBOL(__netif_schedule); 3087 3088 struct dev_kfree_skb_cb { 3089 enum skb_free_reason reason; 3090 }; 3091 3092 static struct dev_kfree_skb_cb *get_kfree_skb_cb(const struct sk_buff *skb) 3093 { 3094 return (struct dev_kfree_skb_cb *)skb->cb; 3095 } 3096 3097 void netif_schedule_queue(struct netdev_queue *txq) 3098 { 3099 rcu_read_lock(); 3100 if (!netif_xmit_stopped(txq)) { 3101 struct Qdisc *q = rcu_dereference(txq->qdisc); 3102 3103 __netif_schedule(q); 3104 } 3105 rcu_read_unlock(); 3106 } 3107 EXPORT_SYMBOL(netif_schedule_queue); 3108 3109 void netif_tx_wake_queue(struct netdev_queue *dev_queue) 3110 { 3111 if (test_and_clear_bit(__QUEUE_STATE_DRV_XOFF, &dev_queue->state)) { 3112 struct Qdisc *q; 3113 3114 rcu_read_lock(); 3115 q = rcu_dereference(dev_queue->qdisc); 3116 __netif_schedule(q); 3117 rcu_read_unlock(); 3118 } 3119 } 3120 EXPORT_SYMBOL(netif_tx_wake_queue); 3121 3122 void __dev_kfree_skb_irq(struct sk_buff *skb, enum skb_free_reason reason) 3123 { 3124 unsigned long flags; 3125 3126 if (unlikely(!skb)) 3127 return; 3128 3129 if (likely(refcount_read(&skb->users) == 1)) { 3130 smp_rmb(); 3131 refcount_set(&skb->users, 0); 3132 } else if (likely(!refcount_dec_and_test(&skb->users))) { 3133 return; 3134 } 3135 get_kfree_skb_cb(skb)->reason = reason; 3136 local_irq_save(flags); 3137 skb->next = __this_cpu_read(softnet_data.completion_queue); 3138 __this_cpu_write(softnet_data.completion_queue, skb); 3139 raise_softirq_irqoff(NET_TX_SOFTIRQ); 3140 local_irq_restore(flags); 3141 } 3142 EXPORT_SYMBOL(__dev_kfree_skb_irq); 3143 3144 void __dev_kfree_skb_any(struct sk_buff *skb, enum skb_free_reason reason) 3145 { 3146 if (in_hardirq() || irqs_disabled()) 3147 __dev_kfree_skb_irq(skb, reason); 3148 else 3149 dev_kfree_skb(skb); 3150 } 3151 EXPORT_SYMBOL(__dev_kfree_skb_any); 3152 3153 3154 /** 3155 * netif_device_detach - mark device as removed 3156 * @dev: network device 3157 * 3158 * Mark device as removed from system and therefore no longer available. 3159 */ 3160 void netif_device_detach(struct net_device *dev) 3161 { 3162 if (test_and_clear_bit(__LINK_STATE_PRESENT, &dev->state) && 3163 netif_running(dev)) { 3164 netif_tx_stop_all_queues(dev); 3165 } 3166 } 3167 EXPORT_SYMBOL(netif_device_detach); 3168 3169 /** 3170 * netif_device_attach - mark device as attached 3171 * @dev: network device 3172 * 3173 * Mark device as attached from system and restart if needed. 3174 */ 3175 void netif_device_attach(struct net_device *dev) 3176 { 3177 if (!test_and_set_bit(__LINK_STATE_PRESENT, &dev->state) && 3178 netif_running(dev)) { 3179 netif_tx_wake_all_queues(dev); 3180 __netdev_watchdog_up(dev); 3181 } 3182 } 3183 EXPORT_SYMBOL(netif_device_attach); 3184 3185 /* 3186 * Returns a Tx hash based on the given packet descriptor a Tx queues' number 3187 * to be used as a distribution range. 3188 */ 3189 static u16 skb_tx_hash(const struct net_device *dev, 3190 const struct net_device *sb_dev, 3191 struct sk_buff *skb) 3192 { 3193 u32 hash; 3194 u16 qoffset = 0; 3195 u16 qcount = dev->real_num_tx_queues; 3196 3197 if (dev->num_tc) { 3198 u8 tc = netdev_get_prio_tc_map(dev, skb->priority); 3199 3200 qoffset = sb_dev->tc_to_txq[tc].offset; 3201 qcount = sb_dev->tc_to_txq[tc].count; 3202 if (unlikely(!qcount)) { 3203 net_warn_ratelimited("%s: invalid qcount, qoffset %u for tc %u\n", 3204 sb_dev->name, qoffset, tc); 3205 qoffset = 0; 3206 qcount = dev->real_num_tx_queues; 3207 } 3208 } 3209 3210 if (skb_rx_queue_recorded(skb)) { 3211 hash = skb_get_rx_queue(skb); 3212 if (hash >= qoffset) 3213 hash -= qoffset; 3214 while (unlikely(hash >= qcount)) 3215 hash -= qcount; 3216 return hash + qoffset; 3217 } 3218 3219 return (u16) reciprocal_scale(skb_get_hash(skb), qcount) + qoffset; 3220 } 3221 3222 static void skb_warn_bad_offload(const struct sk_buff *skb) 3223 { 3224 static const netdev_features_t null_features; 3225 struct net_device *dev = skb->dev; 3226 const char *name = ""; 3227 3228 if (!net_ratelimit()) 3229 return; 3230 3231 if (dev) { 3232 if (dev->dev.parent) 3233 name = dev_driver_string(dev->dev.parent); 3234 else 3235 name = netdev_name(dev); 3236 } 3237 skb_dump(KERN_WARNING, skb, false); 3238 WARN(1, "%s: caps=(%pNF, %pNF)\n", 3239 name, dev ? &dev->features : &null_features, 3240 skb->sk ? &skb->sk->sk_route_caps : &null_features); 3241 } 3242 3243 /* 3244 * Invalidate hardware checksum when packet is to be mangled, and 3245 * complete checksum manually on outgoing path. 3246 */ 3247 int skb_checksum_help(struct sk_buff *skb) 3248 { 3249 __wsum csum; 3250 int ret = 0, offset; 3251 3252 if (skb->ip_summed == CHECKSUM_COMPLETE) 3253 goto out_set_summed; 3254 3255 if (unlikely(skb_is_gso(skb))) { 3256 skb_warn_bad_offload(skb); 3257 return -EINVAL; 3258 } 3259 3260 /* Before computing a checksum, we should make sure no frag could 3261 * be modified by an external entity : checksum could be wrong. 3262 */ 3263 if (skb_has_shared_frag(skb)) { 3264 ret = __skb_linearize(skb); 3265 if (ret) 3266 goto out; 3267 } 3268 3269 offset = skb_checksum_start_offset(skb); 3270 ret = -EINVAL; 3271 if (WARN_ON_ONCE(offset >= skb_headlen(skb))) { 3272 DO_ONCE_LITE(skb_dump, KERN_ERR, skb, false); 3273 goto out; 3274 } 3275 csum = skb_checksum(skb, offset, skb->len - offset, 0); 3276 3277 offset += skb->csum_offset; 3278 if (WARN_ON_ONCE(offset + sizeof(__sum16) > skb_headlen(skb))) { 3279 DO_ONCE_LITE(skb_dump, KERN_ERR, skb, false); 3280 goto out; 3281 } 3282 ret = skb_ensure_writable(skb, offset + sizeof(__sum16)); 3283 if (ret) 3284 goto out; 3285 3286 *(__sum16 *)(skb->data + offset) = csum_fold(csum) ?: CSUM_MANGLED_0; 3287 out_set_summed: 3288 skb->ip_summed = CHECKSUM_NONE; 3289 out: 3290 return ret; 3291 } 3292 EXPORT_SYMBOL(skb_checksum_help); 3293 3294 int skb_crc32c_csum_help(struct sk_buff *skb) 3295 { 3296 __le32 crc32c_csum; 3297 int ret = 0, offset, start; 3298 3299 if (skb->ip_summed != CHECKSUM_PARTIAL) 3300 goto out; 3301 3302 if (unlikely(skb_is_gso(skb))) 3303 goto out; 3304 3305 /* Before computing a checksum, we should make sure no frag could 3306 * be modified by an external entity : checksum could be wrong. 3307 */ 3308 if (unlikely(skb_has_shared_frag(skb))) { 3309 ret = __skb_linearize(skb); 3310 if (ret) 3311 goto out; 3312 } 3313 start = skb_checksum_start_offset(skb); 3314 offset = start + offsetof(struct sctphdr, checksum); 3315 if (WARN_ON_ONCE(offset >= skb_headlen(skb))) { 3316 ret = -EINVAL; 3317 goto out; 3318 } 3319 3320 ret = skb_ensure_writable(skb, offset + sizeof(__le32)); 3321 if (ret) 3322 goto out; 3323 3324 crc32c_csum = cpu_to_le32(~__skb_checksum(skb, start, 3325 skb->len - start, ~(__u32)0, 3326 crc32c_csum_stub)); 3327 *(__le32 *)(skb->data + offset) = crc32c_csum; 3328 skb->ip_summed = CHECKSUM_NONE; 3329 skb->csum_not_inet = 0; 3330 out: 3331 return ret; 3332 } 3333 3334 __be16 skb_network_protocol(struct sk_buff *skb, int *depth) 3335 { 3336 __be16 type = skb->protocol; 3337 3338 /* Tunnel gso handlers can set protocol to ethernet. */ 3339 if (type == htons(ETH_P_TEB)) { 3340 struct ethhdr *eth; 3341 3342 if (unlikely(!pskb_may_pull(skb, sizeof(struct ethhdr)))) 3343 return 0; 3344 3345 eth = (struct ethhdr *)skb->data; 3346 type = eth->h_proto; 3347 } 3348 3349 return __vlan_get_protocol(skb, type, depth); 3350 } 3351 3352 /* openvswitch calls this on rx path, so we need a different check. 3353 */ 3354 static inline bool skb_needs_check(struct sk_buff *skb, bool tx_path) 3355 { 3356 if (tx_path) 3357 return skb->ip_summed != CHECKSUM_PARTIAL && 3358 skb->ip_summed != CHECKSUM_UNNECESSARY; 3359 3360 return skb->ip_summed == CHECKSUM_NONE; 3361 } 3362 3363 /** 3364 * __skb_gso_segment - Perform segmentation on skb. 3365 * @skb: buffer to segment 3366 * @features: features for the output path (see dev->features) 3367 * @tx_path: whether it is called in TX path 3368 * 3369 * This function segments the given skb and returns a list of segments. 3370 * 3371 * It may return NULL if the skb requires no segmentation. This is 3372 * only possible when GSO is used for verifying header integrity. 3373 * 3374 * Segmentation preserves SKB_GSO_CB_OFFSET bytes of previous skb cb. 3375 */ 3376 struct sk_buff *__skb_gso_segment(struct sk_buff *skb, 3377 netdev_features_t features, bool tx_path) 3378 { 3379 struct sk_buff *segs; 3380 3381 if (unlikely(skb_needs_check(skb, tx_path))) { 3382 int err; 3383 3384 /* We're going to init ->check field in TCP or UDP header */ 3385 err = skb_cow_head(skb, 0); 3386 if (err < 0) 3387 return ERR_PTR(err); 3388 } 3389 3390 /* Only report GSO partial support if it will enable us to 3391 * support segmentation on this frame without needing additional 3392 * work. 3393 */ 3394 if (features & NETIF_F_GSO_PARTIAL) { 3395 netdev_features_t partial_features = NETIF_F_GSO_ROBUST; 3396 struct net_device *dev = skb->dev; 3397 3398 partial_features |= dev->features & dev->gso_partial_features; 3399 if (!skb_gso_ok(skb, features | partial_features)) 3400 features &= ~NETIF_F_GSO_PARTIAL; 3401 } 3402 3403 BUILD_BUG_ON(SKB_GSO_CB_OFFSET + 3404 sizeof(*SKB_GSO_CB(skb)) > sizeof(skb->cb)); 3405 3406 SKB_GSO_CB(skb)->mac_offset = skb_headroom(skb); 3407 SKB_GSO_CB(skb)->encap_level = 0; 3408 3409 skb_reset_mac_header(skb); 3410 skb_reset_mac_len(skb); 3411 3412 segs = skb_mac_gso_segment(skb, features); 3413 3414 if (segs != skb && unlikely(skb_needs_check(skb, tx_path) && !IS_ERR(segs))) 3415 skb_warn_bad_offload(skb); 3416 3417 return segs; 3418 } 3419 EXPORT_SYMBOL(__skb_gso_segment); 3420 3421 /* Take action when hardware reception checksum errors are detected. */ 3422 #ifdef CONFIG_BUG 3423 static void do_netdev_rx_csum_fault(struct net_device *dev, struct sk_buff *skb) 3424 { 3425 netdev_err(dev, "hw csum failure\n"); 3426 skb_dump(KERN_ERR, skb, true); 3427 dump_stack(); 3428 } 3429 3430 void netdev_rx_csum_fault(struct net_device *dev, struct sk_buff *skb) 3431 { 3432 DO_ONCE_LITE(do_netdev_rx_csum_fault, dev, skb); 3433 } 3434 EXPORT_SYMBOL(netdev_rx_csum_fault); 3435 #endif 3436 3437 /* XXX: check that highmem exists at all on the given machine. */ 3438 static int illegal_highdma(struct net_device *dev, struct sk_buff *skb) 3439 { 3440 #ifdef CONFIG_HIGHMEM 3441 int i; 3442 3443 if (!(dev->features & NETIF_F_HIGHDMA)) { 3444 for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) { 3445 skb_frag_t *frag = &skb_shinfo(skb)->frags[i]; 3446 3447 if (PageHighMem(skb_frag_page(frag))) 3448 return 1; 3449 } 3450 } 3451 #endif 3452 return 0; 3453 } 3454 3455 /* If MPLS offload request, verify we are testing hardware MPLS features 3456 * instead of standard features for the netdev. 3457 */ 3458 #if IS_ENABLED(CONFIG_NET_MPLS_GSO) 3459 static netdev_features_t net_mpls_features(struct sk_buff *skb, 3460 netdev_features_t features, 3461 __be16 type) 3462 { 3463 if (eth_p_mpls(type)) 3464 features &= skb->dev->mpls_features; 3465 3466 return features; 3467 } 3468 #else 3469 static netdev_features_t net_mpls_features(struct sk_buff *skb, 3470 netdev_features_t features, 3471 __be16 type) 3472 { 3473 return features; 3474 } 3475 #endif 3476 3477 static netdev_features_t harmonize_features(struct sk_buff *skb, 3478 netdev_features_t features) 3479 { 3480 __be16 type; 3481 3482 type = skb_network_protocol(skb, NULL); 3483 features = net_mpls_features(skb, features, type); 3484 3485 if (skb->ip_summed != CHECKSUM_NONE && 3486 !can_checksum_protocol(features, type)) { 3487 features &= ~(NETIF_F_CSUM_MASK | NETIF_F_GSO_MASK); 3488 } 3489 if (illegal_highdma(skb->dev, skb)) 3490 features &= ~NETIF_F_SG; 3491 3492 return features; 3493 } 3494 3495 netdev_features_t passthru_features_check(struct sk_buff *skb, 3496 struct net_device *dev, 3497 netdev_features_t features) 3498 { 3499 return features; 3500 } 3501 EXPORT_SYMBOL(passthru_features_check); 3502 3503 static netdev_features_t dflt_features_check(struct sk_buff *skb, 3504 struct net_device *dev, 3505 netdev_features_t features) 3506 { 3507 return vlan_features_check(skb, features); 3508 } 3509 3510 static netdev_features_t gso_features_check(const struct sk_buff *skb, 3511 struct net_device *dev, 3512 netdev_features_t features) 3513 { 3514 u16 gso_segs = skb_shinfo(skb)->gso_segs; 3515 3516 if (gso_segs > READ_ONCE(dev->gso_max_segs)) 3517 return features & ~NETIF_F_GSO_MASK; 3518 3519 if (!skb_shinfo(skb)->gso_type) { 3520 skb_warn_bad_offload(skb); 3521 return features & ~NETIF_F_GSO_MASK; 3522 } 3523 3524 /* Support for GSO partial features requires software 3525 * intervention before we can actually process the packets 3526 * so we need to strip support for any partial features now 3527 * and we can pull them back in after we have partially 3528 * segmented the frame. 3529 */ 3530 if (!(skb_shinfo(skb)->gso_type & SKB_GSO_PARTIAL)) 3531 features &= ~dev->gso_partial_features; 3532 3533 /* Make sure to clear the IPv4 ID mangling feature if the 3534 * IPv4 header has the potential to be fragmented. 3535 */ 3536 if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV4) { 3537 struct iphdr *iph = skb->encapsulation ? 3538 inner_ip_hdr(skb) : ip_hdr(skb); 3539 3540 if (!(iph->frag_off & htons(IP_DF))) 3541 features &= ~NETIF_F_TSO_MANGLEID; 3542 } 3543 3544 return features; 3545 } 3546 3547 netdev_features_t netif_skb_features(struct sk_buff *skb) 3548 { 3549 struct net_device *dev = skb->dev; 3550 netdev_features_t features = dev->features; 3551 3552 if (skb_is_gso(skb)) 3553 features = gso_features_check(skb, dev, features); 3554 3555 /* If encapsulation offload request, verify we are testing 3556 * hardware encapsulation features instead of standard 3557 * features for the netdev 3558 */ 3559 if (skb->encapsulation) 3560 features &= dev->hw_enc_features; 3561 3562 if (skb_vlan_tagged(skb)) 3563 features = netdev_intersect_features(features, 3564 dev->vlan_features | 3565 NETIF_F_HW_VLAN_CTAG_TX | 3566 NETIF_F_HW_VLAN_STAG_TX); 3567 3568 if (dev->netdev_ops->ndo_features_check) 3569 features &= dev->netdev_ops->ndo_features_check(skb, dev, 3570 features); 3571 else 3572 features &= dflt_features_check(skb, dev, features); 3573 3574 return harmonize_features(skb, features); 3575 } 3576 EXPORT_SYMBOL(netif_skb_features); 3577 3578 static int xmit_one(struct sk_buff *skb, struct net_device *dev, 3579 struct netdev_queue *txq, bool more) 3580 { 3581 unsigned int len; 3582 int rc; 3583 3584 if (dev_nit_active(dev)) 3585 dev_queue_xmit_nit(skb, dev); 3586 3587 len = skb->len; 3588 trace_net_dev_start_xmit(skb, dev); 3589 rc = netdev_start_xmit(skb, dev, txq, more); 3590 trace_net_dev_xmit(skb, rc, dev, len); 3591 3592 return rc; 3593 } 3594 3595 struct sk_buff *dev_hard_start_xmit(struct sk_buff *first, struct net_device *dev, 3596 struct netdev_queue *txq, int *ret) 3597 { 3598 struct sk_buff *skb = first; 3599 int rc = NETDEV_TX_OK; 3600 3601 while (skb) { 3602 struct sk_buff *next = skb->next; 3603 3604 skb_mark_not_on_list(skb); 3605 rc = xmit_one(skb, dev, txq, next != NULL); 3606 if (unlikely(!dev_xmit_complete(rc))) { 3607 skb->next = next; 3608 goto out; 3609 } 3610 3611 skb = next; 3612 if (netif_tx_queue_stopped(txq) && skb) { 3613 rc = NETDEV_TX_BUSY; 3614 break; 3615 } 3616 } 3617 3618 out: 3619 *ret = rc; 3620 return skb; 3621 } 3622 3623 static struct sk_buff *validate_xmit_vlan(struct sk_buff *skb, 3624 netdev_features_t features) 3625 { 3626 if (skb_vlan_tag_present(skb) && 3627 !vlan_hw_offload_capable(features, skb->vlan_proto)) 3628 skb = __vlan_hwaccel_push_inside(skb); 3629 return skb; 3630 } 3631 3632 int skb_csum_hwoffload_help(struct sk_buff *skb, 3633 const netdev_features_t features) 3634 { 3635 if (unlikely(skb_csum_is_sctp(skb))) 3636 return !!(features & NETIF_F_SCTP_CRC) ? 0 : 3637 skb_crc32c_csum_help(skb); 3638 3639 if (features & NETIF_F_HW_CSUM) 3640 return 0; 3641 3642 if (features & (NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM)) { 3643 switch (skb->csum_offset) { 3644 case offsetof(struct tcphdr, check): 3645 case offsetof(struct udphdr, check): 3646 return 0; 3647 } 3648 } 3649 3650 return skb_checksum_help(skb); 3651 } 3652 EXPORT_SYMBOL(skb_csum_hwoffload_help); 3653 3654 static struct sk_buff *validate_xmit_skb(struct sk_buff *skb, struct net_device *dev, bool *again) 3655 { 3656 netdev_features_t features; 3657 3658 features = netif_skb_features(skb); 3659 skb = validate_xmit_vlan(skb, features); 3660 if (unlikely(!skb)) 3661 goto out_null; 3662 3663 skb = sk_validate_xmit_skb(skb, dev); 3664 if (unlikely(!skb)) 3665 goto out_null; 3666 3667 if (netif_needs_gso(skb, features)) { 3668 struct sk_buff *segs; 3669 3670 segs = skb_gso_segment(skb, features); 3671 if (IS_ERR(segs)) { 3672 goto out_kfree_skb; 3673 } else if (segs) { 3674 consume_skb(skb); 3675 skb = segs; 3676 } 3677 } else { 3678 if (skb_needs_linearize(skb, features) && 3679 __skb_linearize(skb)) 3680 goto out_kfree_skb; 3681 3682 /* If packet is not checksummed and device does not 3683 * support checksumming for this protocol, complete 3684 * checksumming here. 3685 */ 3686 if (skb->ip_summed == CHECKSUM_PARTIAL) { 3687 if (skb->encapsulation) 3688 skb_set_inner_transport_header(skb, 3689 skb_checksum_start_offset(skb)); 3690 else 3691 skb_set_transport_header(skb, 3692 skb_checksum_start_offset(skb)); 3693 if (skb_csum_hwoffload_help(skb, features)) 3694 goto out_kfree_skb; 3695 } 3696 } 3697 3698 skb = validate_xmit_xfrm(skb, features, again); 3699 3700 return skb; 3701 3702 out_kfree_skb: 3703 kfree_skb(skb); 3704 out_null: 3705 dev_core_stats_tx_dropped_inc(dev); 3706 return NULL; 3707 } 3708 3709 struct sk_buff *validate_xmit_skb_list(struct sk_buff *skb, struct net_device *dev, bool *again) 3710 { 3711 struct sk_buff *next, *head = NULL, *tail; 3712 3713 for (; skb != NULL; skb = next) { 3714 next = skb->next; 3715 skb_mark_not_on_list(skb); 3716 3717 /* in case skb wont be segmented, point to itself */ 3718 skb->prev = skb; 3719 3720 skb = validate_xmit_skb(skb, dev, again); 3721 if (!skb) 3722 continue; 3723 3724 if (!head) 3725 head = skb; 3726 else 3727 tail->next = skb; 3728 /* If skb was segmented, skb->prev points to 3729 * the last segment. If not, it still contains skb. 3730 */ 3731 tail = skb->prev; 3732 } 3733 return head; 3734 } 3735 EXPORT_SYMBOL_GPL(validate_xmit_skb_list); 3736 3737 static void qdisc_pkt_len_init(struct sk_buff *skb) 3738 { 3739 const struct skb_shared_info *shinfo = skb_shinfo(skb); 3740 3741 qdisc_skb_cb(skb)->pkt_len = skb->len; 3742 3743 /* To get more precise estimation of bytes sent on wire, 3744 * we add to pkt_len the headers size of all segments 3745 */ 3746 if (shinfo->gso_size && skb_transport_header_was_set(skb)) { 3747 unsigned int hdr_len; 3748 u16 gso_segs = shinfo->gso_segs; 3749 3750 /* mac layer + network layer */ 3751 hdr_len = skb_transport_header(skb) - skb_mac_header(skb); 3752 3753 /* + transport layer */ 3754 if (likely(shinfo->gso_type & (SKB_GSO_TCPV4 | SKB_GSO_TCPV6))) { 3755 const struct tcphdr *th; 3756 struct tcphdr _tcphdr; 3757 3758 th = skb_header_pointer(skb, skb_transport_offset(skb), 3759 sizeof(_tcphdr), &_tcphdr); 3760 if (likely(th)) 3761 hdr_len += __tcp_hdrlen(th); 3762 } else { 3763 struct udphdr _udphdr; 3764 3765 if (skb_header_pointer(skb, skb_transport_offset(skb), 3766 sizeof(_udphdr), &_udphdr)) 3767 hdr_len += sizeof(struct udphdr); 3768 } 3769 3770 if (shinfo->gso_type & SKB_GSO_DODGY) 3771 gso_segs = DIV_ROUND_UP(skb->len - hdr_len, 3772 shinfo->gso_size); 3773 3774 qdisc_skb_cb(skb)->pkt_len += (gso_segs - 1) * hdr_len; 3775 } 3776 } 3777 3778 static int dev_qdisc_enqueue(struct sk_buff *skb, struct Qdisc *q, 3779 struct sk_buff **to_free, 3780 struct netdev_queue *txq) 3781 { 3782 int rc; 3783 3784 rc = q->enqueue(skb, q, to_free) & NET_XMIT_MASK; 3785 if (rc == NET_XMIT_SUCCESS) 3786 trace_qdisc_enqueue(q, txq, skb); 3787 return rc; 3788 } 3789 3790 static inline int __dev_xmit_skb(struct sk_buff *skb, struct Qdisc *q, 3791 struct net_device *dev, 3792 struct netdev_queue *txq) 3793 { 3794 spinlock_t *root_lock = qdisc_lock(q); 3795 struct sk_buff *to_free = NULL; 3796 bool contended; 3797 int rc; 3798 3799 qdisc_calculate_pkt_len(skb, q); 3800 3801 if (q->flags & TCQ_F_NOLOCK) { 3802 if (q->flags & TCQ_F_CAN_BYPASS && nolock_qdisc_is_empty(q) && 3803 qdisc_run_begin(q)) { 3804 /* Retest nolock_qdisc_is_empty() within the protection 3805 * of q->seqlock to protect from racing with requeuing. 3806 */ 3807 if (unlikely(!nolock_qdisc_is_empty(q))) { 3808 rc = dev_qdisc_enqueue(skb, q, &to_free, txq); 3809 __qdisc_run(q); 3810 qdisc_run_end(q); 3811 3812 goto no_lock_out; 3813 } 3814 3815 qdisc_bstats_cpu_update(q, skb); 3816 if (sch_direct_xmit(skb, q, dev, txq, NULL, true) && 3817 !nolock_qdisc_is_empty(q)) 3818 __qdisc_run(q); 3819 3820 qdisc_run_end(q); 3821 return NET_XMIT_SUCCESS; 3822 } 3823 3824 rc = dev_qdisc_enqueue(skb, q, &to_free, txq); 3825 qdisc_run(q); 3826 3827 no_lock_out: 3828 if (unlikely(to_free)) 3829 kfree_skb_list_reason(to_free, 3830 SKB_DROP_REASON_QDISC_DROP); 3831 return rc; 3832 } 3833 3834 /* 3835 * Heuristic to force contended enqueues to serialize on a 3836 * separate lock before trying to get qdisc main lock. 3837 * This permits qdisc->running owner to get the lock more 3838 * often and dequeue packets faster. 3839 * On PREEMPT_RT it is possible to preempt the qdisc owner during xmit 3840 * and then other tasks will only enqueue packets. The packets will be 3841 * sent after the qdisc owner is scheduled again. To prevent this 3842 * scenario the task always serialize on the lock. 3843 */ 3844 contended = qdisc_is_running(q) || IS_ENABLED(CONFIG_PREEMPT_RT); 3845 if (unlikely(contended)) 3846 spin_lock(&q->busylock); 3847 3848 spin_lock(root_lock); 3849 if (unlikely(test_bit(__QDISC_STATE_DEACTIVATED, &q->state))) { 3850 __qdisc_drop(skb, &to_free); 3851 rc = NET_XMIT_DROP; 3852 } else if ((q->flags & TCQ_F_CAN_BYPASS) && !qdisc_qlen(q) && 3853 qdisc_run_begin(q)) { 3854 /* 3855 * This is a work-conserving queue; there are no old skbs 3856 * waiting to be sent out; and the qdisc is not running - 3857 * xmit the skb directly. 3858 */ 3859 3860 qdisc_bstats_update(q, skb); 3861 3862 if (sch_direct_xmit(skb, q, dev, txq, root_lock, true)) { 3863 if (unlikely(contended)) { 3864 spin_unlock(&q->busylock); 3865 contended = false; 3866 } 3867 __qdisc_run(q); 3868 } 3869 3870 qdisc_run_end(q); 3871 rc = NET_XMIT_SUCCESS; 3872 } else { 3873 rc = dev_qdisc_enqueue(skb, q, &to_free, txq); 3874 if (qdisc_run_begin(q)) { 3875 if (unlikely(contended)) { 3876 spin_unlock(&q->busylock); 3877 contended = false; 3878 } 3879 __qdisc_run(q); 3880 qdisc_run_end(q); 3881 } 3882 } 3883 spin_unlock(root_lock); 3884 if (unlikely(to_free)) 3885 kfree_skb_list_reason(to_free, SKB_DROP_REASON_QDISC_DROP); 3886 if (unlikely(contended)) 3887 spin_unlock(&q->busylock); 3888 return rc; 3889 } 3890 3891 #if IS_ENABLED(CONFIG_CGROUP_NET_PRIO) 3892 static void skb_update_prio(struct sk_buff *skb) 3893 { 3894 const struct netprio_map *map; 3895 const struct sock *sk; 3896 unsigned int prioidx; 3897 3898 if (skb->priority) 3899 return; 3900 map = rcu_dereference_bh(skb->dev->priomap); 3901 if (!map) 3902 return; 3903 sk = skb_to_full_sk(skb); 3904 if (!sk) 3905 return; 3906 3907 prioidx = sock_cgroup_prioidx(&sk->sk_cgrp_data); 3908 3909 if (prioidx < map->priomap_len) 3910 skb->priority = map->priomap[prioidx]; 3911 } 3912 #else 3913 #define skb_update_prio(skb) 3914 #endif 3915 3916 /** 3917 * dev_loopback_xmit - loop back @skb 3918 * @net: network namespace this loopback is happening in 3919 * @sk: sk needed to be a netfilter okfn 3920 * @skb: buffer to transmit 3921 */ 3922 int dev_loopback_xmit(struct net *net, struct sock *sk, struct sk_buff *skb) 3923 { 3924 skb_reset_mac_header(skb); 3925 __skb_pull(skb, skb_network_offset(skb)); 3926 skb->pkt_type = PACKET_LOOPBACK; 3927 if (skb->ip_summed == CHECKSUM_NONE) 3928 skb->ip_summed = CHECKSUM_UNNECESSARY; 3929 DEBUG_NET_WARN_ON_ONCE(!skb_dst(skb)); 3930 skb_dst_force(skb); 3931 netif_rx(skb); 3932 return 0; 3933 } 3934 EXPORT_SYMBOL(dev_loopback_xmit); 3935 3936 #ifdef CONFIG_NET_EGRESS 3937 static struct sk_buff * 3938 sch_handle_egress(struct sk_buff *skb, int *ret, struct net_device *dev) 3939 { 3940 #ifdef CONFIG_NET_CLS_ACT 3941 struct mini_Qdisc *miniq = rcu_dereference_bh(dev->miniq_egress); 3942 struct tcf_result cl_res; 3943 3944 if (!miniq) 3945 return skb; 3946 3947 /* qdisc_skb_cb(skb)->pkt_len was already set by the caller. */ 3948 tc_skb_cb(skb)->mru = 0; 3949 tc_skb_cb(skb)->post_ct = false; 3950 mini_qdisc_bstats_cpu_update(miniq, skb); 3951 3952 switch (tcf_classify(skb, miniq->block, miniq->filter_list, &cl_res, false)) { 3953 case TC_ACT_OK: 3954 case TC_ACT_RECLASSIFY: 3955 skb->tc_index = TC_H_MIN(cl_res.classid); 3956 break; 3957 case TC_ACT_SHOT: 3958 mini_qdisc_qstats_cpu_drop(miniq); 3959 *ret = NET_XMIT_DROP; 3960 kfree_skb_reason(skb, SKB_DROP_REASON_TC_EGRESS); 3961 return NULL; 3962 case TC_ACT_STOLEN: 3963 case TC_ACT_QUEUED: 3964 case TC_ACT_TRAP: 3965 *ret = NET_XMIT_SUCCESS; 3966 consume_skb(skb); 3967 return NULL; 3968 case TC_ACT_REDIRECT: 3969 /* No need to push/pop skb's mac_header here on egress! */ 3970 skb_do_redirect(skb); 3971 *ret = NET_XMIT_SUCCESS; 3972 return NULL; 3973 default: 3974 break; 3975 } 3976 #endif /* CONFIG_NET_CLS_ACT */ 3977 3978 return skb; 3979 } 3980 3981 static struct netdev_queue * 3982 netdev_tx_queue_mapping(struct net_device *dev, struct sk_buff *skb) 3983 { 3984 int qm = skb_get_queue_mapping(skb); 3985 3986 return netdev_get_tx_queue(dev, netdev_cap_txqueue(dev, qm)); 3987 } 3988 3989 static bool netdev_xmit_txqueue_skipped(void) 3990 { 3991 return __this_cpu_read(softnet_data.xmit.skip_txqueue); 3992 } 3993 3994 void netdev_xmit_skip_txqueue(bool skip) 3995 { 3996 __this_cpu_write(softnet_data.xmit.skip_txqueue, skip); 3997 } 3998 EXPORT_SYMBOL_GPL(netdev_xmit_skip_txqueue); 3999 #endif /* CONFIG_NET_EGRESS */ 4000 4001 #ifdef CONFIG_XPS 4002 static int __get_xps_queue_idx(struct net_device *dev, struct sk_buff *skb, 4003 struct xps_dev_maps *dev_maps, unsigned int tci) 4004 { 4005 int tc = netdev_get_prio_tc_map(dev, skb->priority); 4006 struct xps_map *map; 4007 int queue_index = -1; 4008 4009 if (tc >= dev_maps->num_tc || tci >= dev_maps->nr_ids) 4010 return queue_index; 4011 4012 tci *= dev_maps->num_tc; 4013 tci += tc; 4014 4015 map = rcu_dereference(dev_maps->attr_map[tci]); 4016 if (map) { 4017 if (map->len == 1) 4018 queue_index = map->queues[0]; 4019 else 4020 queue_index = map->queues[reciprocal_scale( 4021 skb_get_hash(skb), map->len)]; 4022 if (unlikely(queue_index >= dev->real_num_tx_queues)) 4023 queue_index = -1; 4024 } 4025 return queue_index; 4026 } 4027 #endif 4028 4029 static int get_xps_queue(struct net_device *dev, struct net_device *sb_dev, 4030 struct sk_buff *skb) 4031 { 4032 #ifdef CONFIG_XPS 4033 struct xps_dev_maps *dev_maps; 4034 struct sock *sk = skb->sk; 4035 int queue_index = -1; 4036 4037 if (!static_key_false(&xps_needed)) 4038 return -1; 4039 4040 rcu_read_lock(); 4041 if (!static_key_false(&xps_rxqs_needed)) 4042 goto get_cpus_map; 4043 4044 dev_maps = rcu_dereference(sb_dev->xps_maps[XPS_RXQS]); 4045 if (dev_maps) { 4046 int tci = sk_rx_queue_get(sk); 4047 4048 if (tci >= 0) 4049 queue_index = __get_xps_queue_idx(dev, skb, dev_maps, 4050 tci); 4051 } 4052 4053 get_cpus_map: 4054 if (queue_index < 0) { 4055 dev_maps = rcu_dereference(sb_dev->xps_maps[XPS_CPUS]); 4056 if (dev_maps) { 4057 unsigned int tci = skb->sender_cpu - 1; 4058 4059 queue_index = __get_xps_queue_idx(dev, skb, dev_maps, 4060 tci); 4061 } 4062 } 4063 rcu_read_unlock(); 4064 4065 return queue_index; 4066 #else 4067 return -1; 4068 #endif 4069 } 4070 4071 u16 dev_pick_tx_zero(struct net_device *dev, struct sk_buff *skb, 4072 struct net_device *sb_dev) 4073 { 4074 return 0; 4075 } 4076 EXPORT_SYMBOL(dev_pick_tx_zero); 4077 4078 u16 dev_pick_tx_cpu_id(struct net_device *dev, struct sk_buff *skb, 4079 struct net_device *sb_dev) 4080 { 4081 return (u16)raw_smp_processor_id() % dev->real_num_tx_queues; 4082 } 4083 EXPORT_SYMBOL(dev_pick_tx_cpu_id); 4084 4085 u16 netdev_pick_tx(struct net_device *dev, struct sk_buff *skb, 4086 struct net_device *sb_dev) 4087 { 4088 struct sock *sk = skb->sk; 4089 int queue_index = sk_tx_queue_get(sk); 4090 4091 sb_dev = sb_dev ? : dev; 4092 4093 if (queue_index < 0 || skb->ooo_okay || 4094 queue_index >= dev->real_num_tx_queues) { 4095 int new_index = get_xps_queue(dev, sb_dev, skb); 4096 4097 if (new_index < 0) 4098 new_index = skb_tx_hash(dev, sb_dev, skb); 4099 4100 if (queue_index != new_index && sk && 4101 sk_fullsock(sk) && 4102 rcu_access_pointer(sk->sk_dst_cache)) 4103 sk_tx_queue_set(sk, new_index); 4104 4105 queue_index = new_index; 4106 } 4107 4108 return queue_index; 4109 } 4110 EXPORT_SYMBOL(netdev_pick_tx); 4111 4112 struct netdev_queue *netdev_core_pick_tx(struct net_device *dev, 4113 struct sk_buff *skb, 4114 struct net_device *sb_dev) 4115 { 4116 int queue_index = 0; 4117 4118 #ifdef CONFIG_XPS 4119 u32 sender_cpu = skb->sender_cpu - 1; 4120 4121 if (sender_cpu >= (u32)NR_CPUS) 4122 skb->sender_cpu = raw_smp_processor_id() + 1; 4123 #endif 4124 4125 if (dev->real_num_tx_queues != 1) { 4126 const struct net_device_ops *ops = dev->netdev_ops; 4127 4128 if (ops->ndo_select_queue) 4129 queue_index = ops->ndo_select_queue(dev, skb, sb_dev); 4130 else 4131 queue_index = netdev_pick_tx(dev, skb, sb_dev); 4132 4133 queue_index = netdev_cap_txqueue(dev, queue_index); 4134 } 4135 4136 skb_set_queue_mapping(skb, queue_index); 4137 return netdev_get_tx_queue(dev, queue_index); 4138 } 4139 4140 /** 4141 * __dev_queue_xmit() - transmit a buffer 4142 * @skb: buffer to transmit 4143 * @sb_dev: suboordinate device used for L2 forwarding offload 4144 * 4145 * Queue a buffer for transmission to a network device. The caller must 4146 * have set the device and priority and built the buffer before calling 4147 * this function. The function can be called from an interrupt. 4148 * 4149 * When calling this method, interrupts MUST be enabled. This is because 4150 * the BH enable code must have IRQs enabled so that it will not deadlock. 4151 * 4152 * Regardless of the return value, the skb is consumed, so it is currently 4153 * difficult to retry a send to this method. (You can bump the ref count 4154 * before sending to hold a reference for retry if you are careful.) 4155 * 4156 * Return: 4157 * * 0 - buffer successfully transmitted 4158 * * positive qdisc return code - NET_XMIT_DROP etc. 4159 * * negative errno - other errors 4160 */ 4161 int __dev_queue_xmit(struct sk_buff *skb, struct net_device *sb_dev) 4162 { 4163 struct net_device *dev = skb->dev; 4164 struct netdev_queue *txq = NULL; 4165 struct Qdisc *q; 4166 int rc = -ENOMEM; 4167 bool again = false; 4168 4169 skb_reset_mac_header(skb); 4170 skb_assert_len(skb); 4171 4172 if (unlikely(skb_shinfo(skb)->tx_flags & SKBTX_SCHED_TSTAMP)) 4173 __skb_tstamp_tx(skb, NULL, NULL, skb->sk, SCM_TSTAMP_SCHED); 4174 4175 /* Disable soft irqs for various locks below. Also 4176 * stops preemption for RCU. 4177 */ 4178 rcu_read_lock_bh(); 4179 4180 skb_update_prio(skb); 4181 4182 qdisc_pkt_len_init(skb); 4183 #ifdef CONFIG_NET_CLS_ACT 4184 skb->tc_at_ingress = 0; 4185 #endif 4186 #ifdef CONFIG_NET_EGRESS 4187 if (static_branch_unlikely(&egress_needed_key)) { 4188 if (nf_hook_egress_active()) { 4189 skb = nf_hook_egress(skb, &rc, dev); 4190 if (!skb) 4191 goto out; 4192 } 4193 4194 netdev_xmit_skip_txqueue(false); 4195 4196 nf_skip_egress(skb, true); 4197 skb = sch_handle_egress(skb, &rc, dev); 4198 if (!skb) 4199 goto out; 4200 nf_skip_egress(skb, false); 4201 4202 if (netdev_xmit_txqueue_skipped()) 4203 txq = netdev_tx_queue_mapping(dev, skb); 4204 } 4205 #endif 4206 /* If device/qdisc don't need skb->dst, release it right now while 4207 * its hot in this cpu cache. 4208 */ 4209 if (dev->priv_flags & IFF_XMIT_DST_RELEASE) 4210 skb_dst_drop(skb); 4211 else 4212 skb_dst_force(skb); 4213 4214 if (!txq) 4215 txq = netdev_core_pick_tx(dev, skb, sb_dev); 4216 4217 q = rcu_dereference_bh(txq->qdisc); 4218 4219 trace_net_dev_queue(skb); 4220 if (q->enqueue) { 4221 rc = __dev_xmit_skb(skb, q, dev, txq); 4222 goto out; 4223 } 4224 4225 /* The device has no queue. Common case for software devices: 4226 * loopback, all the sorts of tunnels... 4227 4228 * Really, it is unlikely that netif_tx_lock protection is necessary 4229 * here. (f.e. loopback and IP tunnels are clean ignoring statistics 4230 * counters.) 4231 * However, it is possible, that they rely on protection 4232 * made by us here. 4233 4234 * Check this and shot the lock. It is not prone from deadlocks. 4235 *Either shot noqueue qdisc, it is even simpler 8) 4236 */ 4237 if (dev->flags & IFF_UP) { 4238 int cpu = smp_processor_id(); /* ok because BHs are off */ 4239 4240 /* Other cpus might concurrently change txq->xmit_lock_owner 4241 * to -1 or to their cpu id, but not to our id. 4242 */ 4243 if (READ_ONCE(txq->xmit_lock_owner) != cpu) { 4244 if (dev_xmit_recursion()) 4245 goto recursion_alert; 4246 4247 skb = validate_xmit_skb(skb, dev, &again); 4248 if (!skb) 4249 goto out; 4250 4251 HARD_TX_LOCK(dev, txq, cpu); 4252 4253 if (!netif_xmit_stopped(txq)) { 4254 dev_xmit_recursion_inc(); 4255 skb = dev_hard_start_xmit(skb, dev, txq, &rc); 4256 dev_xmit_recursion_dec(); 4257 if (dev_xmit_complete(rc)) { 4258 HARD_TX_UNLOCK(dev, txq); 4259 goto out; 4260 } 4261 } 4262 HARD_TX_UNLOCK(dev, txq); 4263 net_crit_ratelimited("Virtual device %s asks to queue packet!\n", 4264 dev->name); 4265 } else { 4266 /* Recursion is detected! It is possible, 4267 * unfortunately 4268 */ 4269 recursion_alert: 4270 net_crit_ratelimited("Dead loop on virtual device %s, fix it urgently!\n", 4271 dev->name); 4272 } 4273 } 4274 4275 rc = -ENETDOWN; 4276 rcu_read_unlock_bh(); 4277 4278 dev_core_stats_tx_dropped_inc(dev); 4279 kfree_skb_list(skb); 4280 return rc; 4281 out: 4282 rcu_read_unlock_bh(); 4283 return rc; 4284 } 4285 EXPORT_SYMBOL(__dev_queue_xmit); 4286 4287 int __dev_direct_xmit(struct sk_buff *skb, u16 queue_id) 4288 { 4289 struct net_device *dev = skb->dev; 4290 struct sk_buff *orig_skb = skb; 4291 struct netdev_queue *txq; 4292 int ret = NETDEV_TX_BUSY; 4293 bool again = false; 4294 4295 if (unlikely(!netif_running(dev) || 4296 !netif_carrier_ok(dev))) 4297 goto drop; 4298 4299 skb = validate_xmit_skb_list(skb, dev, &again); 4300 if (skb != orig_skb) 4301 goto drop; 4302 4303 skb_set_queue_mapping(skb, queue_id); 4304 txq = skb_get_tx_queue(dev, skb); 4305 4306 local_bh_disable(); 4307 4308 dev_xmit_recursion_inc(); 4309 HARD_TX_LOCK(dev, txq, smp_processor_id()); 4310 if (!netif_xmit_frozen_or_drv_stopped(txq)) 4311 ret = netdev_start_xmit(skb, dev, txq, false); 4312 HARD_TX_UNLOCK(dev, txq); 4313 dev_xmit_recursion_dec(); 4314 4315 local_bh_enable(); 4316 return ret; 4317 drop: 4318 dev_core_stats_tx_dropped_inc(dev); 4319 kfree_skb_list(skb); 4320 return NET_XMIT_DROP; 4321 } 4322 EXPORT_SYMBOL(__dev_direct_xmit); 4323 4324 /************************************************************************* 4325 * Receiver routines 4326 *************************************************************************/ 4327 4328 int netdev_max_backlog __read_mostly = 1000; 4329 EXPORT_SYMBOL(netdev_max_backlog); 4330 4331 int netdev_tstamp_prequeue __read_mostly = 1; 4332 unsigned int sysctl_skb_defer_max __read_mostly = 64; 4333 int netdev_budget __read_mostly = 300; 4334 /* Must be at least 2 jiffes to guarantee 1 jiffy timeout */ 4335 unsigned int __read_mostly netdev_budget_usecs = 2 * USEC_PER_SEC / HZ; 4336 int weight_p __read_mostly = 64; /* old backlog weight */ 4337 int dev_weight_rx_bias __read_mostly = 1; /* bias for backlog weight */ 4338 int dev_weight_tx_bias __read_mostly = 1; /* bias for output_queue quota */ 4339 int dev_rx_weight __read_mostly = 64; 4340 int dev_tx_weight __read_mostly = 64; 4341 4342 /* Called with irq disabled */ 4343 static inline void ____napi_schedule(struct softnet_data *sd, 4344 struct napi_struct *napi) 4345 { 4346 struct task_struct *thread; 4347 4348 lockdep_assert_irqs_disabled(); 4349 4350 if (test_bit(NAPI_STATE_THREADED, &napi->state)) { 4351 /* Paired with smp_mb__before_atomic() in 4352 * napi_enable()/dev_set_threaded(). 4353 * Use READ_ONCE() to guarantee a complete 4354 * read on napi->thread. Only call 4355 * wake_up_process() when it's not NULL. 4356 */ 4357 thread = READ_ONCE(napi->thread); 4358 if (thread) { 4359 /* Avoid doing set_bit() if the thread is in 4360 * INTERRUPTIBLE state, cause napi_thread_wait() 4361 * makes sure to proceed with napi polling 4362 * if the thread is explicitly woken from here. 4363 */ 4364 if (READ_ONCE(thread->__state) != TASK_INTERRUPTIBLE) 4365 set_bit(NAPI_STATE_SCHED_THREADED, &napi->state); 4366 wake_up_process(thread); 4367 return; 4368 } 4369 } 4370 4371 list_add_tail(&napi->poll_list, &sd->poll_list); 4372 __raise_softirq_irqoff(NET_RX_SOFTIRQ); 4373 } 4374 4375 #ifdef CONFIG_RPS 4376 4377 /* One global table that all flow-based protocols share. */ 4378 struct rps_sock_flow_table __rcu *rps_sock_flow_table __read_mostly; 4379 EXPORT_SYMBOL(rps_sock_flow_table); 4380 u32 rps_cpu_mask __read_mostly; 4381 EXPORT_SYMBOL(rps_cpu_mask); 4382 4383 struct static_key_false rps_needed __read_mostly; 4384 EXPORT_SYMBOL(rps_needed); 4385 struct static_key_false rfs_needed __read_mostly; 4386 EXPORT_SYMBOL(rfs_needed); 4387 4388 static struct rps_dev_flow * 4389 set_rps_cpu(struct net_device *dev, struct sk_buff *skb, 4390 struct rps_dev_flow *rflow, u16 next_cpu) 4391 { 4392 if (next_cpu < nr_cpu_ids) { 4393 #ifdef CONFIG_RFS_ACCEL 4394 struct netdev_rx_queue *rxqueue; 4395 struct rps_dev_flow_table *flow_table; 4396 struct rps_dev_flow *old_rflow; 4397 u32 flow_id; 4398 u16 rxq_index; 4399 int rc; 4400 4401 /* Should we steer this flow to a different hardware queue? */ 4402 if (!skb_rx_queue_recorded(skb) || !dev->rx_cpu_rmap || 4403 !(dev->features & NETIF_F_NTUPLE)) 4404 goto out; 4405 rxq_index = cpu_rmap_lookup_index(dev->rx_cpu_rmap, next_cpu); 4406 if (rxq_index == skb_get_rx_queue(skb)) 4407 goto out; 4408 4409 rxqueue = dev->_rx + rxq_index; 4410 flow_table = rcu_dereference(rxqueue->rps_flow_table); 4411 if (!flow_table) 4412 goto out; 4413 flow_id = skb_get_hash(skb) & flow_table->mask; 4414 rc = dev->netdev_ops->ndo_rx_flow_steer(dev, skb, 4415 rxq_index, flow_id); 4416 if (rc < 0) 4417 goto out; 4418 old_rflow = rflow; 4419 rflow = &flow_table->flows[flow_id]; 4420 rflow->filter = rc; 4421 if (old_rflow->filter == rflow->filter) 4422 old_rflow->filter = RPS_NO_FILTER; 4423 out: 4424 #endif 4425 rflow->last_qtail = 4426 per_cpu(softnet_data, next_cpu).input_queue_head; 4427 } 4428 4429 rflow->cpu = next_cpu; 4430 return rflow; 4431 } 4432 4433 /* 4434 * get_rps_cpu is called from netif_receive_skb and returns the target 4435 * CPU from the RPS map of the receiving queue for a given skb. 4436 * rcu_read_lock must be held on entry. 4437 */ 4438 static int get_rps_cpu(struct net_device *dev, struct sk_buff *skb, 4439 struct rps_dev_flow **rflowp) 4440 { 4441 const struct rps_sock_flow_table *sock_flow_table; 4442 struct netdev_rx_queue *rxqueue = dev->_rx; 4443 struct rps_dev_flow_table *flow_table; 4444 struct rps_map *map; 4445 int cpu = -1; 4446 u32 tcpu; 4447 u32 hash; 4448 4449 if (skb_rx_queue_recorded(skb)) { 4450 u16 index = skb_get_rx_queue(skb); 4451 4452 if (unlikely(index >= dev->real_num_rx_queues)) { 4453 WARN_ONCE(dev->real_num_rx_queues > 1, 4454 "%s received packet on queue %u, but number " 4455 "of RX queues is %u\n", 4456 dev->name, index, dev->real_num_rx_queues); 4457 goto done; 4458 } 4459 rxqueue += index; 4460 } 4461 4462 /* Avoid computing hash if RFS/RPS is not active for this rxqueue */ 4463 4464 flow_table = rcu_dereference(rxqueue->rps_flow_table); 4465 map = rcu_dereference(rxqueue->rps_map); 4466 if (!flow_table && !map) 4467 goto done; 4468 4469 skb_reset_network_header(skb); 4470 hash = skb_get_hash(skb); 4471 if (!hash) 4472 goto done; 4473 4474 sock_flow_table = rcu_dereference(rps_sock_flow_table); 4475 if (flow_table && sock_flow_table) { 4476 struct rps_dev_flow *rflow; 4477 u32 next_cpu; 4478 u32 ident; 4479 4480 /* First check into global flow table if there is a match */ 4481 ident = sock_flow_table->ents[hash & sock_flow_table->mask]; 4482 if ((ident ^ hash) & ~rps_cpu_mask) 4483 goto try_rps; 4484 4485 next_cpu = ident & rps_cpu_mask; 4486 4487 /* OK, now we know there is a match, 4488 * we can look at the local (per receive queue) flow table 4489 */ 4490 rflow = &flow_table->flows[hash & flow_table->mask]; 4491 tcpu = rflow->cpu; 4492 4493 /* 4494 * If the desired CPU (where last recvmsg was done) is 4495 * different from current CPU (one in the rx-queue flow 4496 * table entry), switch if one of the following holds: 4497 * - Current CPU is unset (>= nr_cpu_ids). 4498 * - Current CPU is offline. 4499 * - The current CPU's queue tail has advanced beyond the 4500 * last packet that was enqueued using this table entry. 4501 * This guarantees that all previous packets for the flow 4502 * have been dequeued, thus preserving in order delivery. 4503 */ 4504 if (unlikely(tcpu != next_cpu) && 4505 (tcpu >= nr_cpu_ids || !cpu_online(tcpu) || 4506 ((int)(per_cpu(softnet_data, tcpu).input_queue_head - 4507 rflow->last_qtail)) >= 0)) { 4508 tcpu = next_cpu; 4509 rflow = set_rps_cpu(dev, skb, rflow, next_cpu); 4510 } 4511 4512 if (tcpu < nr_cpu_ids && cpu_online(tcpu)) { 4513 *rflowp = rflow; 4514 cpu = tcpu; 4515 goto done; 4516 } 4517 } 4518 4519 try_rps: 4520 4521 if (map) { 4522 tcpu = map->cpus[reciprocal_scale(hash, map->len)]; 4523 if (cpu_online(tcpu)) { 4524 cpu = tcpu; 4525 goto done; 4526 } 4527 } 4528 4529 done: 4530 return cpu; 4531 } 4532 4533 #ifdef CONFIG_RFS_ACCEL 4534 4535 /** 4536 * rps_may_expire_flow - check whether an RFS hardware filter may be removed 4537 * @dev: Device on which the filter was set 4538 * @rxq_index: RX queue index 4539 * @flow_id: Flow ID passed to ndo_rx_flow_steer() 4540 * @filter_id: Filter ID returned by ndo_rx_flow_steer() 4541 * 4542 * Drivers that implement ndo_rx_flow_steer() should periodically call 4543 * this function for each installed filter and remove the filters for 4544 * which it returns %true. 4545 */ 4546 bool rps_may_expire_flow(struct net_device *dev, u16 rxq_index, 4547 u32 flow_id, u16 filter_id) 4548 { 4549 struct netdev_rx_queue *rxqueue = dev->_rx + rxq_index; 4550 struct rps_dev_flow_table *flow_table; 4551 struct rps_dev_flow *rflow; 4552 bool expire = true; 4553 unsigned int cpu; 4554 4555 rcu_read_lock(); 4556 flow_table = rcu_dereference(rxqueue->rps_flow_table); 4557 if (flow_table && flow_id <= flow_table->mask) { 4558 rflow = &flow_table->flows[flow_id]; 4559 cpu = READ_ONCE(rflow->cpu); 4560 if (rflow->filter == filter_id && cpu < nr_cpu_ids && 4561 ((int)(per_cpu(softnet_data, cpu).input_queue_head - 4562 rflow->last_qtail) < 4563 (int)(10 * flow_table->mask))) 4564 expire = false; 4565 } 4566 rcu_read_unlock(); 4567 return expire; 4568 } 4569 EXPORT_SYMBOL(rps_may_expire_flow); 4570 4571 #endif /* CONFIG_RFS_ACCEL */ 4572 4573 /* Called from hardirq (IPI) context */ 4574 static void rps_trigger_softirq(void *data) 4575 { 4576 struct softnet_data *sd = data; 4577 4578 ____napi_schedule(sd, &sd->backlog); 4579 sd->received_rps++; 4580 } 4581 4582 #endif /* CONFIG_RPS */ 4583 4584 /* Called from hardirq (IPI) context */ 4585 static void trigger_rx_softirq(void *data) 4586 { 4587 struct softnet_data *sd = data; 4588 4589 __raise_softirq_irqoff(NET_RX_SOFTIRQ); 4590 smp_store_release(&sd->defer_ipi_scheduled, 0); 4591 } 4592 4593 /* 4594 * Check if this softnet_data structure is another cpu one 4595 * If yes, queue it to our IPI list and return 1 4596 * If no, return 0 4597 */ 4598 static int napi_schedule_rps(struct softnet_data *sd) 4599 { 4600 struct softnet_data *mysd = this_cpu_ptr(&softnet_data); 4601 4602 #ifdef CONFIG_RPS 4603 if (sd != mysd) { 4604 sd->rps_ipi_next = mysd->rps_ipi_list; 4605 mysd->rps_ipi_list = sd; 4606 4607 __raise_softirq_irqoff(NET_RX_SOFTIRQ); 4608 return 1; 4609 } 4610 #endif /* CONFIG_RPS */ 4611 __napi_schedule_irqoff(&mysd->backlog); 4612 return 0; 4613 } 4614 4615 #ifdef CONFIG_NET_FLOW_LIMIT 4616 int netdev_flow_limit_table_len __read_mostly = (1 << 12); 4617 #endif 4618 4619 static bool skb_flow_limit(struct sk_buff *skb, unsigned int qlen) 4620 { 4621 #ifdef CONFIG_NET_FLOW_LIMIT 4622 struct sd_flow_limit *fl; 4623 struct softnet_data *sd; 4624 unsigned int old_flow, new_flow; 4625 4626 if (qlen < (READ_ONCE(netdev_max_backlog) >> 1)) 4627 return false; 4628 4629 sd = this_cpu_ptr(&softnet_data); 4630 4631 rcu_read_lock(); 4632 fl = rcu_dereference(sd->flow_limit); 4633 if (fl) { 4634 new_flow = skb_get_hash(skb) & (fl->num_buckets - 1); 4635 old_flow = fl->history[fl->history_head]; 4636 fl->history[fl->history_head] = new_flow; 4637 4638 fl->history_head++; 4639 fl->history_head &= FLOW_LIMIT_HISTORY - 1; 4640 4641 if (likely(fl->buckets[old_flow])) 4642 fl->buckets[old_flow]--; 4643 4644 if (++fl->buckets[new_flow] > (FLOW_LIMIT_HISTORY >> 1)) { 4645 fl->count++; 4646 rcu_read_unlock(); 4647 return true; 4648 } 4649 } 4650 rcu_read_unlock(); 4651 #endif 4652 return false; 4653 } 4654 4655 /* 4656 * enqueue_to_backlog is called to queue an skb to a per CPU backlog 4657 * queue (may be a remote CPU queue). 4658 */ 4659 static int enqueue_to_backlog(struct sk_buff *skb, int cpu, 4660 unsigned int *qtail) 4661 { 4662 enum skb_drop_reason reason; 4663 struct softnet_data *sd; 4664 unsigned long flags; 4665 unsigned int qlen; 4666 4667 reason = SKB_DROP_REASON_NOT_SPECIFIED; 4668 sd = &per_cpu(softnet_data, cpu); 4669 4670 rps_lock_irqsave(sd, &flags); 4671 if (!netif_running(skb->dev)) 4672 goto drop; 4673 qlen = skb_queue_len(&sd->input_pkt_queue); 4674 if (qlen <= READ_ONCE(netdev_max_backlog) && !skb_flow_limit(skb, qlen)) { 4675 if (qlen) { 4676 enqueue: 4677 __skb_queue_tail(&sd->input_pkt_queue, skb); 4678 input_queue_tail_incr_save(sd, qtail); 4679 rps_unlock_irq_restore(sd, &flags); 4680 return NET_RX_SUCCESS; 4681 } 4682 4683 /* Schedule NAPI for backlog device 4684 * We can use non atomic operation since we own the queue lock 4685 */ 4686 if (!__test_and_set_bit(NAPI_STATE_SCHED, &sd->backlog.state)) 4687 napi_schedule_rps(sd); 4688 goto enqueue; 4689 } 4690 reason = SKB_DROP_REASON_CPU_BACKLOG; 4691 4692 drop: 4693 sd->dropped++; 4694 rps_unlock_irq_restore(sd, &flags); 4695 4696 dev_core_stats_rx_dropped_inc(skb->dev); 4697 kfree_skb_reason(skb, reason); 4698 return NET_RX_DROP; 4699 } 4700 4701 static struct netdev_rx_queue *netif_get_rxqueue(struct sk_buff *skb) 4702 { 4703 struct net_device *dev = skb->dev; 4704 struct netdev_rx_queue *rxqueue; 4705 4706 rxqueue = dev->_rx; 4707 4708 if (skb_rx_queue_recorded(skb)) { 4709 u16 index = skb_get_rx_queue(skb); 4710 4711 if (unlikely(index >= dev->real_num_rx_queues)) { 4712 WARN_ONCE(dev->real_num_rx_queues > 1, 4713 "%s received packet on queue %u, but number " 4714 "of RX queues is %u\n", 4715 dev->name, index, dev->real_num_rx_queues); 4716 4717 return rxqueue; /* Return first rxqueue */ 4718 } 4719 rxqueue += index; 4720 } 4721 return rxqueue; 4722 } 4723 4724 u32 bpf_prog_run_generic_xdp(struct sk_buff *skb, struct xdp_buff *xdp, 4725 struct bpf_prog *xdp_prog) 4726 { 4727 void *orig_data, *orig_data_end, *hard_start; 4728 struct netdev_rx_queue *rxqueue; 4729 bool orig_bcast, orig_host; 4730 u32 mac_len, frame_sz; 4731 __be16 orig_eth_type; 4732 struct ethhdr *eth; 4733 u32 metalen, act; 4734 int off; 4735 4736 /* The XDP program wants to see the packet starting at the MAC 4737 * header. 4738 */ 4739 mac_len = skb->data - skb_mac_header(skb); 4740 hard_start = skb->data - skb_headroom(skb); 4741 4742 /* SKB "head" area always have tailroom for skb_shared_info */ 4743 frame_sz = (void *)skb_end_pointer(skb) - hard_start; 4744 frame_sz += SKB_DATA_ALIGN(sizeof(struct skb_shared_info)); 4745 4746 rxqueue = netif_get_rxqueue(skb); 4747 xdp_init_buff(xdp, frame_sz, &rxqueue->xdp_rxq); 4748 xdp_prepare_buff(xdp, hard_start, skb_headroom(skb) - mac_len, 4749 skb_headlen(skb) + mac_len, true); 4750 4751 orig_data_end = xdp->data_end; 4752 orig_data = xdp->data; 4753 eth = (struct ethhdr *)xdp->data; 4754 orig_host = ether_addr_equal_64bits(eth->h_dest, skb->dev->dev_addr); 4755 orig_bcast = is_multicast_ether_addr_64bits(eth->h_dest); 4756 orig_eth_type = eth->h_proto; 4757 4758 act = bpf_prog_run_xdp(xdp_prog, xdp); 4759 4760 /* check if bpf_xdp_adjust_head was used */ 4761 off = xdp->data - orig_data; 4762 if (off) { 4763 if (off > 0) 4764 __skb_pull(skb, off); 4765 else if (off < 0) 4766 __skb_push(skb, -off); 4767 4768 skb->mac_header += off; 4769 skb_reset_network_header(skb); 4770 } 4771 4772 /* check if bpf_xdp_adjust_tail was used */ 4773 off = xdp->data_end - orig_data_end; 4774 if (off != 0) { 4775 skb_set_tail_pointer(skb, xdp->data_end - xdp->data); 4776 skb->len += off; /* positive on grow, negative on shrink */ 4777 } 4778 4779 /* check if XDP changed eth hdr such SKB needs update */ 4780 eth = (struct ethhdr *)xdp->data; 4781 if ((orig_eth_type != eth->h_proto) || 4782 (orig_host != ether_addr_equal_64bits(eth->h_dest, 4783 skb->dev->dev_addr)) || 4784 (orig_bcast != is_multicast_ether_addr_64bits(eth->h_dest))) { 4785 __skb_push(skb, ETH_HLEN); 4786 skb->pkt_type = PACKET_HOST; 4787 skb->protocol = eth_type_trans(skb, skb->dev); 4788 } 4789 4790 /* Redirect/Tx gives L2 packet, code that will reuse skb must __skb_pull 4791 * before calling us again on redirect path. We do not call do_redirect 4792 * as we leave that up to the caller. 4793 * 4794 * Caller is responsible for managing lifetime of skb (i.e. calling 4795 * kfree_skb in response to actions it cannot handle/XDP_DROP). 4796 */ 4797 switch (act) { 4798 case XDP_REDIRECT: 4799 case XDP_TX: 4800 __skb_push(skb, mac_len); 4801 break; 4802 case XDP_PASS: 4803 metalen = xdp->data - xdp->data_meta; 4804 if (metalen) 4805 skb_metadata_set(skb, metalen); 4806 break; 4807 } 4808 4809 return act; 4810 } 4811 4812 static u32 netif_receive_generic_xdp(struct sk_buff *skb, 4813 struct xdp_buff *xdp, 4814 struct bpf_prog *xdp_prog) 4815 { 4816 u32 act = XDP_DROP; 4817 4818 /* Reinjected packets coming from act_mirred or similar should 4819 * not get XDP generic processing. 4820 */ 4821 if (skb_is_redirected(skb)) 4822 return XDP_PASS; 4823 4824 /* XDP packets must be linear and must have sufficient headroom 4825 * of XDP_PACKET_HEADROOM bytes. This is the guarantee that also 4826 * native XDP provides, thus we need to do it here as well. 4827 */ 4828 if (skb_cloned(skb) || skb_is_nonlinear(skb) || 4829 skb_headroom(skb) < XDP_PACKET_HEADROOM) { 4830 int hroom = XDP_PACKET_HEADROOM - skb_headroom(skb); 4831 int troom = skb->tail + skb->data_len - skb->end; 4832 4833 /* In case we have to go down the path and also linearize, 4834 * then lets do the pskb_expand_head() work just once here. 4835 */ 4836 if (pskb_expand_head(skb, 4837 hroom > 0 ? ALIGN(hroom, NET_SKB_PAD) : 0, 4838 troom > 0 ? troom + 128 : 0, GFP_ATOMIC)) 4839 goto do_drop; 4840 if (skb_linearize(skb)) 4841 goto do_drop; 4842 } 4843 4844 act = bpf_prog_run_generic_xdp(skb, xdp, xdp_prog); 4845 switch (act) { 4846 case XDP_REDIRECT: 4847 case XDP_TX: 4848 case XDP_PASS: 4849 break; 4850 default: 4851 bpf_warn_invalid_xdp_action(skb->dev, xdp_prog, act); 4852 fallthrough; 4853 case XDP_ABORTED: 4854 trace_xdp_exception(skb->dev, xdp_prog, act); 4855 fallthrough; 4856 case XDP_DROP: 4857 do_drop: 4858 kfree_skb(skb); 4859 break; 4860 } 4861 4862 return act; 4863 } 4864 4865 /* When doing generic XDP we have to bypass the qdisc layer and the 4866 * network taps in order to match in-driver-XDP behavior. This also means 4867 * that XDP packets are able to starve other packets going through a qdisc, 4868 * and DDOS attacks will be more effective. In-driver-XDP use dedicated TX 4869 * queues, so they do not have this starvation issue. 4870 */ 4871 void generic_xdp_tx(struct sk_buff *skb, struct bpf_prog *xdp_prog) 4872 { 4873 struct net_device *dev = skb->dev; 4874 struct netdev_queue *txq; 4875 bool free_skb = true; 4876 int cpu, rc; 4877 4878 txq = netdev_core_pick_tx(dev, skb, NULL); 4879 cpu = smp_processor_id(); 4880 HARD_TX_LOCK(dev, txq, cpu); 4881 if (!netif_xmit_frozen_or_drv_stopped(txq)) { 4882 rc = netdev_start_xmit(skb, dev, txq, 0); 4883 if (dev_xmit_complete(rc)) 4884 free_skb = false; 4885 } 4886 HARD_TX_UNLOCK(dev, txq); 4887 if (free_skb) { 4888 trace_xdp_exception(dev, xdp_prog, XDP_TX); 4889 dev_core_stats_tx_dropped_inc(dev); 4890 kfree_skb(skb); 4891 } 4892 } 4893 4894 static DEFINE_STATIC_KEY_FALSE(generic_xdp_needed_key); 4895 4896 int do_xdp_generic(struct bpf_prog *xdp_prog, struct sk_buff *skb) 4897 { 4898 if (xdp_prog) { 4899 struct xdp_buff xdp; 4900 u32 act; 4901 int err; 4902 4903 act = netif_receive_generic_xdp(skb, &xdp, xdp_prog); 4904 if (act != XDP_PASS) { 4905 switch (act) { 4906 case XDP_REDIRECT: 4907 err = xdp_do_generic_redirect(skb->dev, skb, 4908 &xdp, xdp_prog); 4909 if (err) 4910 goto out_redir; 4911 break; 4912 case XDP_TX: 4913 generic_xdp_tx(skb, xdp_prog); 4914 break; 4915 } 4916 return XDP_DROP; 4917 } 4918 } 4919 return XDP_PASS; 4920 out_redir: 4921 kfree_skb_reason(skb, SKB_DROP_REASON_XDP); 4922 return XDP_DROP; 4923 } 4924 EXPORT_SYMBOL_GPL(do_xdp_generic); 4925 4926 static int netif_rx_internal(struct sk_buff *skb) 4927 { 4928 int ret; 4929 4930 net_timestamp_check(READ_ONCE(netdev_tstamp_prequeue), skb); 4931 4932 trace_netif_rx(skb); 4933 4934 #ifdef CONFIG_RPS 4935 if (static_branch_unlikely(&rps_needed)) { 4936 struct rps_dev_flow voidflow, *rflow = &voidflow; 4937 int cpu; 4938 4939 rcu_read_lock(); 4940 4941 cpu = get_rps_cpu(skb->dev, skb, &rflow); 4942 if (cpu < 0) 4943 cpu = smp_processor_id(); 4944 4945 ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail); 4946 4947 rcu_read_unlock(); 4948 } else 4949 #endif 4950 { 4951 unsigned int qtail; 4952 4953 ret = enqueue_to_backlog(skb, smp_processor_id(), &qtail); 4954 } 4955 return ret; 4956 } 4957 4958 /** 4959 * __netif_rx - Slightly optimized version of netif_rx 4960 * @skb: buffer to post 4961 * 4962 * This behaves as netif_rx except that it does not disable bottom halves. 4963 * As a result this function may only be invoked from the interrupt context 4964 * (either hard or soft interrupt). 4965 */ 4966 int __netif_rx(struct sk_buff *skb) 4967 { 4968 int ret; 4969 4970 lockdep_assert_once(hardirq_count() | softirq_count()); 4971 4972 trace_netif_rx_entry(skb); 4973 ret = netif_rx_internal(skb); 4974 trace_netif_rx_exit(ret); 4975 return ret; 4976 } 4977 EXPORT_SYMBOL(__netif_rx); 4978 4979 /** 4980 * netif_rx - post buffer to the network code 4981 * @skb: buffer to post 4982 * 4983 * This function receives a packet from a device driver and queues it for 4984 * the upper (protocol) levels to process via the backlog NAPI device. It 4985 * always succeeds. The buffer may be dropped during processing for 4986 * congestion control or by the protocol layers. 4987 * The network buffer is passed via the backlog NAPI device. Modern NIC 4988 * driver should use NAPI and GRO. 4989 * This function can used from interrupt and from process context. The 4990 * caller from process context must not disable interrupts before invoking 4991 * this function. 4992 * 4993 * return values: 4994 * NET_RX_SUCCESS (no congestion) 4995 * NET_RX_DROP (packet was dropped) 4996 * 4997 */ 4998 int netif_rx(struct sk_buff *skb) 4999 { 5000 bool need_bh_off = !(hardirq_count() | softirq_count()); 5001 int ret; 5002 5003 if (need_bh_off) 5004 local_bh_disable(); 5005 trace_netif_rx_entry(skb); 5006 ret = netif_rx_internal(skb); 5007 trace_netif_rx_exit(ret); 5008 if (need_bh_off) 5009 local_bh_enable(); 5010 return ret; 5011 } 5012 EXPORT_SYMBOL(netif_rx); 5013 5014 static __latent_entropy void net_tx_action(struct softirq_action *h) 5015 { 5016 struct softnet_data *sd = this_cpu_ptr(&softnet_data); 5017 5018 if (sd->completion_queue) { 5019 struct sk_buff *clist; 5020 5021 local_irq_disable(); 5022 clist = sd->completion_queue; 5023 sd->completion_queue = NULL; 5024 local_irq_enable(); 5025 5026 while (clist) { 5027 struct sk_buff *skb = clist; 5028 5029 clist = clist->next; 5030 5031 WARN_ON(refcount_read(&skb->users)); 5032 if (likely(get_kfree_skb_cb(skb)->reason == SKB_REASON_CONSUMED)) 5033 trace_consume_skb(skb); 5034 else 5035 trace_kfree_skb(skb, net_tx_action, 5036 SKB_DROP_REASON_NOT_SPECIFIED); 5037 5038 if (skb->fclone != SKB_FCLONE_UNAVAILABLE) 5039 __kfree_skb(skb); 5040 else 5041 __kfree_skb_defer(skb); 5042 } 5043 } 5044 5045 if (sd->output_queue) { 5046 struct Qdisc *head; 5047 5048 local_irq_disable(); 5049 head = sd->output_queue; 5050 sd->output_queue = NULL; 5051 sd->output_queue_tailp = &sd->output_queue; 5052 local_irq_enable(); 5053 5054 rcu_read_lock(); 5055 5056 while (head) { 5057 struct Qdisc *q = head; 5058 spinlock_t *root_lock = NULL; 5059 5060 head = head->next_sched; 5061 5062 /* We need to make sure head->next_sched is read 5063 * before clearing __QDISC_STATE_SCHED 5064 */ 5065 smp_mb__before_atomic(); 5066 5067 if (!(q->flags & TCQ_F_NOLOCK)) { 5068 root_lock = qdisc_lock(q); 5069 spin_lock(root_lock); 5070 } else if (unlikely(test_bit(__QDISC_STATE_DEACTIVATED, 5071 &q->state))) { 5072 /* There is a synchronize_net() between 5073 * STATE_DEACTIVATED flag being set and 5074 * qdisc_reset()/some_qdisc_is_busy() in 5075 * dev_deactivate(), so we can safely bail out 5076 * early here to avoid data race between 5077 * qdisc_deactivate() and some_qdisc_is_busy() 5078 * for lockless qdisc. 5079 */ 5080 clear_bit(__QDISC_STATE_SCHED, &q->state); 5081 continue; 5082 } 5083 5084 clear_bit(__QDISC_STATE_SCHED, &q->state); 5085 qdisc_run(q); 5086 if (root_lock) 5087 spin_unlock(root_lock); 5088 } 5089 5090 rcu_read_unlock(); 5091 } 5092 5093 xfrm_dev_backlog(sd); 5094 } 5095 5096 #if IS_ENABLED(CONFIG_BRIDGE) && IS_ENABLED(CONFIG_ATM_LANE) 5097 /* This hook is defined here for ATM LANE */ 5098 int (*br_fdb_test_addr_hook)(struct net_device *dev, 5099 unsigned char *addr) __read_mostly; 5100 EXPORT_SYMBOL_GPL(br_fdb_test_addr_hook); 5101 #endif 5102 5103 static inline struct sk_buff * 5104 sch_handle_ingress(struct sk_buff *skb, struct packet_type **pt_prev, int *ret, 5105 struct net_device *orig_dev, bool *another) 5106 { 5107 #ifdef CONFIG_NET_CLS_ACT 5108 struct mini_Qdisc *miniq = rcu_dereference_bh(skb->dev->miniq_ingress); 5109 struct tcf_result cl_res; 5110 5111 /* If there's at least one ingress present somewhere (so 5112 * we get here via enabled static key), remaining devices 5113 * that are not configured with an ingress qdisc will bail 5114 * out here. 5115 */ 5116 if (!miniq) 5117 return skb; 5118 5119 if (*pt_prev) { 5120 *ret = deliver_skb(skb, *pt_prev, orig_dev); 5121 *pt_prev = NULL; 5122 } 5123 5124 qdisc_skb_cb(skb)->pkt_len = skb->len; 5125 tc_skb_cb(skb)->mru = 0; 5126 tc_skb_cb(skb)->post_ct = false; 5127 skb->tc_at_ingress = 1; 5128 mini_qdisc_bstats_cpu_update(miniq, skb); 5129 5130 switch (tcf_classify(skb, miniq->block, miniq->filter_list, &cl_res, false)) { 5131 case TC_ACT_OK: 5132 case TC_ACT_RECLASSIFY: 5133 skb->tc_index = TC_H_MIN(cl_res.classid); 5134 break; 5135 case TC_ACT_SHOT: 5136 mini_qdisc_qstats_cpu_drop(miniq); 5137 kfree_skb_reason(skb, SKB_DROP_REASON_TC_INGRESS); 5138 *ret = NET_RX_DROP; 5139 return NULL; 5140 case TC_ACT_STOLEN: 5141 case TC_ACT_QUEUED: 5142 case TC_ACT_TRAP: 5143 consume_skb(skb); 5144 *ret = NET_RX_SUCCESS; 5145 return NULL; 5146 case TC_ACT_REDIRECT: 5147 /* skb_mac_header check was done by cls/act_bpf, so 5148 * we can safely push the L2 header back before 5149 * redirecting to another netdev 5150 */ 5151 __skb_push(skb, skb->mac_len); 5152 if (skb_do_redirect(skb) == -EAGAIN) { 5153 __skb_pull(skb, skb->mac_len); 5154 *another = true; 5155 break; 5156 } 5157 *ret = NET_RX_SUCCESS; 5158 return NULL; 5159 case TC_ACT_CONSUMED: 5160 *ret = NET_RX_SUCCESS; 5161 return NULL; 5162 default: 5163 break; 5164 } 5165 #endif /* CONFIG_NET_CLS_ACT */ 5166 return skb; 5167 } 5168 5169 /** 5170 * netdev_is_rx_handler_busy - check if receive handler is registered 5171 * @dev: device to check 5172 * 5173 * Check if a receive handler is already registered for a given device. 5174 * Return true if there one. 5175 * 5176 * The caller must hold the rtnl_mutex. 5177 */ 5178 bool netdev_is_rx_handler_busy(struct net_device *dev) 5179 { 5180 ASSERT_RTNL(); 5181 return dev && rtnl_dereference(dev->rx_handler); 5182 } 5183 EXPORT_SYMBOL_GPL(netdev_is_rx_handler_busy); 5184 5185 /** 5186 * netdev_rx_handler_register - register receive handler 5187 * @dev: device to register a handler for 5188 * @rx_handler: receive handler to register 5189 * @rx_handler_data: data pointer that is used by rx handler 5190 * 5191 * Register a receive handler for a device. This handler will then be 5192 * called from __netif_receive_skb. A negative errno code is returned 5193 * on a failure. 5194 * 5195 * The caller must hold the rtnl_mutex. 5196 * 5197 * For a general description of rx_handler, see enum rx_handler_result. 5198 */ 5199 int netdev_rx_handler_register(struct net_device *dev, 5200 rx_handler_func_t *rx_handler, 5201 void *rx_handler_data) 5202 { 5203 if (netdev_is_rx_handler_busy(dev)) 5204 return -EBUSY; 5205 5206 if (dev->priv_flags & IFF_NO_RX_HANDLER) 5207 return -EINVAL; 5208 5209 /* Note: rx_handler_data must be set before rx_handler */ 5210 rcu_assign_pointer(dev->rx_handler_data, rx_handler_data); 5211 rcu_assign_pointer(dev->rx_handler, rx_handler); 5212 5213 return 0; 5214 } 5215 EXPORT_SYMBOL_GPL(netdev_rx_handler_register); 5216 5217 /** 5218 * netdev_rx_handler_unregister - unregister receive handler 5219 * @dev: device to unregister a handler from 5220 * 5221 * Unregister a receive handler from a device. 5222 * 5223 * The caller must hold the rtnl_mutex. 5224 */ 5225 void netdev_rx_handler_unregister(struct net_device *dev) 5226 { 5227 5228 ASSERT_RTNL(); 5229 RCU_INIT_POINTER(dev->rx_handler, NULL); 5230 /* a reader seeing a non NULL rx_handler in a rcu_read_lock() 5231 * section has a guarantee to see a non NULL rx_handler_data 5232 * as well. 5233 */ 5234 synchronize_net(); 5235 RCU_INIT_POINTER(dev->rx_handler_data, NULL); 5236 } 5237 EXPORT_SYMBOL_GPL(netdev_rx_handler_unregister); 5238 5239 /* 5240 * Limit the use of PFMEMALLOC reserves to those protocols that implement 5241 * the special handling of PFMEMALLOC skbs. 5242 */ 5243 static bool skb_pfmemalloc_protocol(struct sk_buff *skb) 5244 { 5245 switch (skb->protocol) { 5246 case htons(ETH_P_ARP): 5247 case htons(ETH_P_IP): 5248 case htons(ETH_P_IPV6): 5249 case htons(ETH_P_8021Q): 5250 case htons(ETH_P_8021AD): 5251 return true; 5252 default: 5253 return false; 5254 } 5255 } 5256 5257 static inline int nf_ingress(struct sk_buff *skb, struct packet_type **pt_prev, 5258 int *ret, struct net_device *orig_dev) 5259 { 5260 if (nf_hook_ingress_active(skb)) { 5261 int ingress_retval; 5262 5263 if (*pt_prev) { 5264 *ret = deliver_skb(skb, *pt_prev, orig_dev); 5265 *pt_prev = NULL; 5266 } 5267 5268 rcu_read_lock(); 5269 ingress_retval = nf_hook_ingress(skb); 5270 rcu_read_unlock(); 5271 return ingress_retval; 5272 } 5273 return 0; 5274 } 5275 5276 static int __netif_receive_skb_core(struct sk_buff **pskb, bool pfmemalloc, 5277 struct packet_type **ppt_prev) 5278 { 5279 struct packet_type *ptype, *pt_prev; 5280 rx_handler_func_t *rx_handler; 5281 struct sk_buff *skb = *pskb; 5282 struct net_device *orig_dev; 5283 bool deliver_exact = false; 5284 int ret = NET_RX_DROP; 5285 __be16 type; 5286 5287 net_timestamp_check(!READ_ONCE(netdev_tstamp_prequeue), skb); 5288 5289 trace_netif_receive_skb(skb); 5290 5291 orig_dev = skb->dev; 5292 5293 skb_reset_network_header(skb); 5294 if (!skb_transport_header_was_set(skb)) 5295 skb_reset_transport_header(skb); 5296 skb_reset_mac_len(skb); 5297 5298 pt_prev = NULL; 5299 5300 another_round: 5301 skb->skb_iif = skb->dev->ifindex; 5302 5303 __this_cpu_inc(softnet_data.processed); 5304 5305 if (static_branch_unlikely(&generic_xdp_needed_key)) { 5306 int ret2; 5307 5308 migrate_disable(); 5309 ret2 = do_xdp_generic(rcu_dereference(skb->dev->xdp_prog), skb); 5310 migrate_enable(); 5311 5312 if (ret2 != XDP_PASS) { 5313 ret = NET_RX_DROP; 5314 goto out; 5315 } 5316 } 5317 5318 if (eth_type_vlan(skb->protocol)) { 5319 skb = skb_vlan_untag(skb); 5320 if (unlikely(!skb)) 5321 goto out; 5322 } 5323 5324 if (skb_skip_tc_classify(skb)) 5325 goto skip_classify; 5326 5327 if (pfmemalloc) 5328 goto skip_taps; 5329 5330 list_for_each_entry_rcu(ptype, &ptype_all, list) { 5331 if (pt_prev) 5332 ret = deliver_skb(skb, pt_prev, orig_dev); 5333 pt_prev = ptype; 5334 } 5335 5336 list_for_each_entry_rcu(ptype, &skb->dev->ptype_all, list) { 5337 if (pt_prev) 5338 ret = deliver_skb(skb, pt_prev, orig_dev); 5339 pt_prev = ptype; 5340 } 5341 5342 skip_taps: 5343 #ifdef CONFIG_NET_INGRESS 5344 if (static_branch_unlikely(&ingress_needed_key)) { 5345 bool another = false; 5346 5347 nf_skip_egress(skb, true); 5348 skb = sch_handle_ingress(skb, &pt_prev, &ret, orig_dev, 5349 &another); 5350 if (another) 5351 goto another_round; 5352 if (!skb) 5353 goto out; 5354 5355 nf_skip_egress(skb, false); 5356 if (nf_ingress(skb, &pt_prev, &ret, orig_dev) < 0) 5357 goto out; 5358 } 5359 #endif 5360 skb_reset_redirect(skb); 5361 skip_classify: 5362 if (pfmemalloc && !skb_pfmemalloc_protocol(skb)) 5363 goto drop; 5364 5365 if (skb_vlan_tag_present(skb)) { 5366 if (pt_prev) { 5367 ret = deliver_skb(skb, pt_prev, orig_dev); 5368 pt_prev = NULL; 5369 } 5370 if (vlan_do_receive(&skb)) 5371 goto another_round; 5372 else if (unlikely(!skb)) 5373 goto out; 5374 } 5375 5376 rx_handler = rcu_dereference(skb->dev->rx_handler); 5377 if (rx_handler) { 5378 if (pt_prev) { 5379 ret = deliver_skb(skb, pt_prev, orig_dev); 5380 pt_prev = NULL; 5381 } 5382 switch (rx_handler(&skb)) { 5383 case RX_HANDLER_CONSUMED: 5384 ret = NET_RX_SUCCESS; 5385 goto out; 5386 case RX_HANDLER_ANOTHER: 5387 goto another_round; 5388 case RX_HANDLER_EXACT: 5389 deliver_exact = true; 5390 break; 5391 case RX_HANDLER_PASS: 5392 break; 5393 default: 5394 BUG(); 5395 } 5396 } 5397 5398 if (unlikely(skb_vlan_tag_present(skb)) && !netdev_uses_dsa(skb->dev)) { 5399 check_vlan_id: 5400 if (skb_vlan_tag_get_id(skb)) { 5401 /* Vlan id is non 0 and vlan_do_receive() above couldn't 5402 * find vlan device. 5403 */ 5404 skb->pkt_type = PACKET_OTHERHOST; 5405 } else if (eth_type_vlan(skb->protocol)) { 5406 /* Outer header is 802.1P with vlan 0, inner header is 5407 * 802.1Q or 802.1AD and vlan_do_receive() above could 5408 * not find vlan dev for vlan id 0. 5409 */ 5410 __vlan_hwaccel_clear_tag(skb); 5411 skb = skb_vlan_untag(skb); 5412 if (unlikely(!skb)) 5413 goto out; 5414 if (vlan_do_receive(&skb)) 5415 /* After stripping off 802.1P header with vlan 0 5416 * vlan dev is found for inner header. 5417 */ 5418 goto another_round; 5419 else if (unlikely(!skb)) 5420 goto out; 5421 else 5422 /* We have stripped outer 802.1P vlan 0 header. 5423 * But could not find vlan dev. 5424 * check again for vlan id to set OTHERHOST. 5425 */ 5426 goto check_vlan_id; 5427 } 5428 /* Note: we might in the future use prio bits 5429 * and set skb->priority like in vlan_do_receive() 5430 * For the time being, just ignore Priority Code Point 5431 */ 5432 __vlan_hwaccel_clear_tag(skb); 5433 } 5434 5435 type = skb->protocol; 5436 5437 /* deliver only exact match when indicated */ 5438 if (likely(!deliver_exact)) { 5439 deliver_ptype_list_skb(skb, &pt_prev, orig_dev, type, 5440 &ptype_base[ntohs(type) & 5441 PTYPE_HASH_MASK]); 5442 } 5443 5444 deliver_ptype_list_skb(skb, &pt_prev, orig_dev, type, 5445 &orig_dev->ptype_specific); 5446 5447 if (unlikely(skb->dev != orig_dev)) { 5448 deliver_ptype_list_skb(skb, &pt_prev, orig_dev, type, 5449 &skb->dev->ptype_specific); 5450 } 5451 5452 if (pt_prev) { 5453 if (unlikely(skb_orphan_frags_rx(skb, GFP_ATOMIC))) 5454 goto drop; 5455 *ppt_prev = pt_prev; 5456 } else { 5457 drop: 5458 if (!deliver_exact) 5459 dev_core_stats_rx_dropped_inc(skb->dev); 5460 else 5461 dev_core_stats_rx_nohandler_inc(skb->dev); 5462 kfree_skb_reason(skb, SKB_DROP_REASON_UNHANDLED_PROTO); 5463 /* Jamal, now you will not able to escape explaining 5464 * me how you were going to use this. :-) 5465 */ 5466 ret = NET_RX_DROP; 5467 } 5468 5469 out: 5470 /* The invariant here is that if *ppt_prev is not NULL 5471 * then skb should also be non-NULL. 5472 * 5473 * Apparently *ppt_prev assignment above holds this invariant due to 5474 * skb dereferencing near it. 5475 */ 5476 *pskb = skb; 5477 return ret; 5478 } 5479 5480 static int __netif_receive_skb_one_core(struct sk_buff *skb, bool pfmemalloc) 5481 { 5482 struct net_device *orig_dev = skb->dev; 5483 struct packet_type *pt_prev = NULL; 5484 int ret; 5485 5486 ret = __netif_receive_skb_core(&skb, pfmemalloc, &pt_prev); 5487 if (pt_prev) 5488 ret = INDIRECT_CALL_INET(pt_prev->func, ipv6_rcv, ip_rcv, skb, 5489 skb->dev, pt_prev, orig_dev); 5490 return ret; 5491 } 5492 5493 /** 5494 * netif_receive_skb_core - special purpose version of netif_receive_skb 5495 * @skb: buffer to process 5496 * 5497 * More direct receive version of netif_receive_skb(). It should 5498 * only be used by callers that have a need to skip RPS and Generic XDP. 5499 * Caller must also take care of handling if ``(page_is_)pfmemalloc``. 5500 * 5501 * This function may only be called from softirq context and interrupts 5502 * should be enabled. 5503 * 5504 * Return values (usually ignored): 5505 * NET_RX_SUCCESS: no congestion 5506 * NET_RX_DROP: packet was dropped 5507 */ 5508 int netif_receive_skb_core(struct sk_buff *skb) 5509 { 5510 int ret; 5511 5512 rcu_read_lock(); 5513 ret = __netif_receive_skb_one_core(skb, false); 5514 rcu_read_unlock(); 5515 5516 return ret; 5517 } 5518 EXPORT_SYMBOL(netif_receive_skb_core); 5519 5520 static inline void __netif_receive_skb_list_ptype(struct list_head *head, 5521 struct packet_type *pt_prev, 5522 struct net_device *orig_dev) 5523 { 5524 struct sk_buff *skb, *next; 5525 5526 if (!pt_prev) 5527 return; 5528 if (list_empty(head)) 5529 return; 5530 if (pt_prev->list_func != NULL) 5531 INDIRECT_CALL_INET(pt_prev->list_func, ipv6_list_rcv, 5532 ip_list_rcv, head, pt_prev, orig_dev); 5533 else 5534 list_for_each_entry_safe(skb, next, head, list) { 5535 skb_list_del_init(skb); 5536 pt_prev->func(skb, skb->dev, pt_prev, orig_dev); 5537 } 5538 } 5539 5540 static void __netif_receive_skb_list_core(struct list_head *head, bool pfmemalloc) 5541 { 5542 /* Fast-path assumptions: 5543 * - There is no RX handler. 5544 * - Only one packet_type matches. 5545 * If either of these fails, we will end up doing some per-packet 5546 * processing in-line, then handling the 'last ptype' for the whole 5547 * sublist. This can't cause out-of-order delivery to any single ptype, 5548 * because the 'last ptype' must be constant across the sublist, and all 5549 * other ptypes are handled per-packet. 5550 */ 5551 /* Current (common) ptype of sublist */ 5552 struct packet_type *pt_curr = NULL; 5553 /* Current (common) orig_dev of sublist */ 5554 struct net_device *od_curr = NULL; 5555 struct list_head sublist; 5556 struct sk_buff *skb, *next; 5557 5558 INIT_LIST_HEAD(&sublist); 5559 list_for_each_entry_safe(skb, next, head, list) { 5560 struct net_device *orig_dev = skb->dev; 5561 struct packet_type *pt_prev = NULL; 5562 5563 skb_list_del_init(skb); 5564 __netif_receive_skb_core(&skb, pfmemalloc, &pt_prev); 5565 if (!pt_prev) 5566 continue; 5567 if (pt_curr != pt_prev || od_curr != orig_dev) { 5568 /* dispatch old sublist */ 5569 __netif_receive_skb_list_ptype(&sublist, pt_curr, od_curr); 5570 /* start new sublist */ 5571 INIT_LIST_HEAD(&sublist); 5572 pt_curr = pt_prev; 5573 od_curr = orig_dev; 5574 } 5575 list_add_tail(&skb->list, &sublist); 5576 } 5577 5578 /* dispatch final sublist */ 5579 __netif_receive_skb_list_ptype(&sublist, pt_curr, od_curr); 5580 } 5581 5582 static int __netif_receive_skb(struct sk_buff *skb) 5583 { 5584 int ret; 5585 5586 if (sk_memalloc_socks() && skb_pfmemalloc(skb)) { 5587 unsigned int noreclaim_flag; 5588 5589 /* 5590 * PFMEMALLOC skbs are special, they should 5591 * - be delivered to SOCK_MEMALLOC sockets only 5592 * - stay away from userspace 5593 * - have bounded memory usage 5594 * 5595 * Use PF_MEMALLOC as this saves us from propagating the allocation 5596 * context down to all allocation sites. 5597 */ 5598 noreclaim_flag = memalloc_noreclaim_save(); 5599 ret = __netif_receive_skb_one_core(skb, true); 5600 memalloc_noreclaim_restore(noreclaim_flag); 5601 } else 5602 ret = __netif_receive_skb_one_core(skb, false); 5603 5604 return ret; 5605 } 5606 5607 static void __netif_receive_skb_list(struct list_head *head) 5608 { 5609 unsigned long noreclaim_flag = 0; 5610 struct sk_buff *skb, *next; 5611 bool pfmemalloc = false; /* Is current sublist PF_MEMALLOC? */ 5612 5613 list_for_each_entry_safe(skb, next, head, list) { 5614 if ((sk_memalloc_socks() && skb_pfmemalloc(skb)) != pfmemalloc) { 5615 struct list_head sublist; 5616 5617 /* Handle the previous sublist */ 5618 list_cut_before(&sublist, head, &skb->list); 5619 if (!list_empty(&sublist)) 5620 __netif_receive_skb_list_core(&sublist, pfmemalloc); 5621 pfmemalloc = !pfmemalloc; 5622 /* See comments in __netif_receive_skb */ 5623 if (pfmemalloc) 5624 noreclaim_flag = memalloc_noreclaim_save(); 5625 else 5626 memalloc_noreclaim_restore(noreclaim_flag); 5627 } 5628 } 5629 /* Handle the remaining sublist */ 5630 if (!list_empty(head)) 5631 __netif_receive_skb_list_core(head, pfmemalloc); 5632 /* Restore pflags */ 5633 if (pfmemalloc) 5634 memalloc_noreclaim_restore(noreclaim_flag); 5635 } 5636 5637 static int generic_xdp_install(struct net_device *dev, struct netdev_bpf *xdp) 5638 { 5639 struct bpf_prog *old = rtnl_dereference(dev->xdp_prog); 5640 struct bpf_prog *new = xdp->prog; 5641 int ret = 0; 5642 5643 switch (xdp->command) { 5644 case XDP_SETUP_PROG: 5645 rcu_assign_pointer(dev->xdp_prog, new); 5646 if (old) 5647 bpf_prog_put(old); 5648 5649 if (old && !new) { 5650 static_branch_dec(&generic_xdp_needed_key); 5651 } else if (new && !old) { 5652 static_branch_inc(&generic_xdp_needed_key); 5653 dev_disable_lro(dev); 5654 dev_disable_gro_hw(dev); 5655 } 5656 break; 5657 5658 default: 5659 ret = -EINVAL; 5660 break; 5661 } 5662 5663 return ret; 5664 } 5665 5666 static int netif_receive_skb_internal(struct sk_buff *skb) 5667 { 5668 int ret; 5669 5670 net_timestamp_check(READ_ONCE(netdev_tstamp_prequeue), skb); 5671 5672 if (skb_defer_rx_timestamp(skb)) 5673 return NET_RX_SUCCESS; 5674 5675 rcu_read_lock(); 5676 #ifdef CONFIG_RPS 5677 if (static_branch_unlikely(&rps_needed)) { 5678 struct rps_dev_flow voidflow, *rflow = &voidflow; 5679 int cpu = get_rps_cpu(skb->dev, skb, &rflow); 5680 5681 if (cpu >= 0) { 5682 ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail); 5683 rcu_read_unlock(); 5684 return ret; 5685 } 5686 } 5687 #endif 5688 ret = __netif_receive_skb(skb); 5689 rcu_read_unlock(); 5690 return ret; 5691 } 5692 5693 void netif_receive_skb_list_internal(struct list_head *head) 5694 { 5695 struct sk_buff *skb, *next; 5696 struct list_head sublist; 5697 5698 INIT_LIST_HEAD(&sublist); 5699 list_for_each_entry_safe(skb, next, head, list) { 5700 net_timestamp_check(READ_ONCE(netdev_tstamp_prequeue), skb); 5701 skb_list_del_init(skb); 5702 if (!skb_defer_rx_timestamp(skb)) 5703 list_add_tail(&skb->list, &sublist); 5704 } 5705 list_splice_init(&sublist, head); 5706 5707 rcu_read_lock(); 5708 #ifdef CONFIG_RPS 5709 if (static_branch_unlikely(&rps_needed)) { 5710 list_for_each_entry_safe(skb, next, head, list) { 5711 struct rps_dev_flow voidflow, *rflow = &voidflow; 5712 int cpu = get_rps_cpu(skb->dev, skb, &rflow); 5713 5714 if (cpu >= 0) { 5715 /* Will be handled, remove from list */ 5716 skb_list_del_init(skb); 5717 enqueue_to_backlog(skb, cpu, &rflow->last_qtail); 5718 } 5719 } 5720 } 5721 #endif 5722 __netif_receive_skb_list(head); 5723 rcu_read_unlock(); 5724 } 5725 5726 /** 5727 * netif_receive_skb - process receive buffer from network 5728 * @skb: buffer to process 5729 * 5730 * netif_receive_skb() is the main receive data processing function. 5731 * It always succeeds. The buffer may be dropped during processing 5732 * for congestion control or by the protocol layers. 5733 * 5734 * This function may only be called from softirq context and interrupts 5735 * should be enabled. 5736 * 5737 * Return values (usually ignored): 5738 * NET_RX_SUCCESS: no congestion 5739 * NET_RX_DROP: packet was dropped 5740 */ 5741 int netif_receive_skb(struct sk_buff *skb) 5742 { 5743 int ret; 5744 5745 trace_netif_receive_skb_entry(skb); 5746 5747 ret = netif_receive_skb_internal(skb); 5748 trace_netif_receive_skb_exit(ret); 5749 5750 return ret; 5751 } 5752 EXPORT_SYMBOL(netif_receive_skb); 5753 5754 /** 5755 * netif_receive_skb_list - process many receive buffers from network 5756 * @head: list of skbs to process. 5757 * 5758 * Since return value of netif_receive_skb() is normally ignored, and 5759 * wouldn't be meaningful for a list, this function returns void. 5760 * 5761 * This function may only be called from softirq context and interrupts 5762 * should be enabled. 5763 */ 5764 void netif_receive_skb_list(struct list_head *head) 5765 { 5766 struct sk_buff *skb; 5767 5768 if (list_empty(head)) 5769 return; 5770 if (trace_netif_receive_skb_list_entry_enabled()) { 5771 list_for_each_entry(skb, head, list) 5772 trace_netif_receive_skb_list_entry(skb); 5773 } 5774 netif_receive_skb_list_internal(head); 5775 trace_netif_receive_skb_list_exit(0); 5776 } 5777 EXPORT_SYMBOL(netif_receive_skb_list); 5778 5779 static DEFINE_PER_CPU(struct work_struct, flush_works); 5780 5781 /* Network device is going away, flush any packets still pending */ 5782 static void flush_backlog(struct work_struct *work) 5783 { 5784 struct sk_buff *skb, *tmp; 5785 struct softnet_data *sd; 5786 5787 local_bh_disable(); 5788 sd = this_cpu_ptr(&softnet_data); 5789 5790 rps_lock_irq_disable(sd); 5791 skb_queue_walk_safe(&sd->input_pkt_queue, skb, tmp) { 5792 if (skb->dev->reg_state == NETREG_UNREGISTERING) { 5793 __skb_unlink(skb, &sd->input_pkt_queue); 5794 dev_kfree_skb_irq(skb); 5795 input_queue_head_incr(sd); 5796 } 5797 } 5798 rps_unlock_irq_enable(sd); 5799 5800 skb_queue_walk_safe(&sd->process_queue, skb, tmp) { 5801 if (skb->dev->reg_state == NETREG_UNREGISTERING) { 5802 __skb_unlink(skb, &sd->process_queue); 5803 kfree_skb(skb); 5804 input_queue_head_incr(sd); 5805 } 5806 } 5807 local_bh_enable(); 5808 } 5809 5810 static bool flush_required(int cpu) 5811 { 5812 #if IS_ENABLED(CONFIG_RPS) 5813 struct softnet_data *sd = &per_cpu(softnet_data, cpu); 5814 bool do_flush; 5815 5816 rps_lock_irq_disable(sd); 5817 5818 /* as insertion into process_queue happens with the rps lock held, 5819 * process_queue access may race only with dequeue 5820 */ 5821 do_flush = !skb_queue_empty(&sd->input_pkt_queue) || 5822 !skb_queue_empty_lockless(&sd->process_queue); 5823 rps_unlock_irq_enable(sd); 5824 5825 return do_flush; 5826 #endif 5827 /* without RPS we can't safely check input_pkt_queue: during a 5828 * concurrent remote skb_queue_splice() we can detect as empty both 5829 * input_pkt_queue and process_queue even if the latter could end-up 5830 * containing a lot of packets. 5831 */ 5832 return true; 5833 } 5834 5835 static void flush_all_backlogs(void) 5836 { 5837 static cpumask_t flush_cpus; 5838 unsigned int cpu; 5839 5840 /* since we are under rtnl lock protection we can use static data 5841 * for the cpumask and avoid allocating on stack the possibly 5842 * large mask 5843 */ 5844 ASSERT_RTNL(); 5845 5846 cpus_read_lock(); 5847 5848 cpumask_clear(&flush_cpus); 5849 for_each_online_cpu(cpu) { 5850 if (flush_required(cpu)) { 5851 queue_work_on(cpu, system_highpri_wq, 5852 per_cpu_ptr(&flush_works, cpu)); 5853 cpumask_set_cpu(cpu, &flush_cpus); 5854 } 5855 } 5856 5857 /* we can have in flight packet[s] on the cpus we are not flushing, 5858 * synchronize_net() in unregister_netdevice_many() will take care of 5859 * them 5860 */ 5861 for_each_cpu(cpu, &flush_cpus) 5862 flush_work(per_cpu_ptr(&flush_works, cpu)); 5863 5864 cpus_read_unlock(); 5865 } 5866 5867 static void net_rps_send_ipi(struct softnet_data *remsd) 5868 { 5869 #ifdef CONFIG_RPS 5870 while (remsd) { 5871 struct softnet_data *next = remsd->rps_ipi_next; 5872 5873 if (cpu_online(remsd->cpu)) 5874 smp_call_function_single_async(remsd->cpu, &remsd->csd); 5875 remsd = next; 5876 } 5877 #endif 5878 } 5879 5880 /* 5881 * net_rps_action_and_irq_enable sends any pending IPI's for rps. 5882 * Note: called with local irq disabled, but exits with local irq enabled. 5883 */ 5884 static void net_rps_action_and_irq_enable(struct softnet_data *sd) 5885 { 5886 #ifdef CONFIG_RPS 5887 struct softnet_data *remsd = sd->rps_ipi_list; 5888 5889 if (remsd) { 5890 sd->rps_ipi_list = NULL; 5891 5892 local_irq_enable(); 5893 5894 /* Send pending IPI's to kick RPS processing on remote cpus. */ 5895 net_rps_send_ipi(remsd); 5896 } else 5897 #endif 5898 local_irq_enable(); 5899 } 5900 5901 static bool sd_has_rps_ipi_waiting(struct softnet_data *sd) 5902 { 5903 #ifdef CONFIG_RPS 5904 return sd->rps_ipi_list != NULL; 5905 #else 5906 return false; 5907 #endif 5908 } 5909 5910 static int process_backlog(struct napi_struct *napi, int quota) 5911 { 5912 struct softnet_data *sd = container_of(napi, struct softnet_data, backlog); 5913 bool again = true; 5914 int work = 0; 5915 5916 /* Check if we have pending ipi, its better to send them now, 5917 * not waiting net_rx_action() end. 5918 */ 5919 if (sd_has_rps_ipi_waiting(sd)) { 5920 local_irq_disable(); 5921 net_rps_action_and_irq_enable(sd); 5922 } 5923 5924 napi->weight = READ_ONCE(dev_rx_weight); 5925 while (again) { 5926 struct sk_buff *skb; 5927 5928 while ((skb = __skb_dequeue(&sd->process_queue))) { 5929 rcu_read_lock(); 5930 __netif_receive_skb(skb); 5931 rcu_read_unlock(); 5932 input_queue_head_incr(sd); 5933 if (++work >= quota) 5934 return work; 5935 5936 } 5937 5938 rps_lock_irq_disable(sd); 5939 if (skb_queue_empty(&sd->input_pkt_queue)) { 5940 /* 5941 * Inline a custom version of __napi_complete(). 5942 * only current cpu owns and manipulates this napi, 5943 * and NAPI_STATE_SCHED is the only possible flag set 5944 * on backlog. 5945 * We can use a plain write instead of clear_bit(), 5946 * and we dont need an smp_mb() memory barrier. 5947 */ 5948 napi->state = 0; 5949 again = false; 5950 } else { 5951 skb_queue_splice_tail_init(&sd->input_pkt_queue, 5952 &sd->process_queue); 5953 } 5954 rps_unlock_irq_enable(sd); 5955 } 5956 5957 return work; 5958 } 5959 5960 /** 5961 * __napi_schedule - schedule for receive 5962 * @n: entry to schedule 5963 * 5964 * The entry's receive function will be scheduled to run. 5965 * Consider using __napi_schedule_irqoff() if hard irqs are masked. 5966 */ 5967 void __napi_schedule(struct napi_struct *n) 5968 { 5969 unsigned long flags; 5970 5971 local_irq_save(flags); 5972 ____napi_schedule(this_cpu_ptr(&softnet_data), n); 5973 local_irq_restore(flags); 5974 } 5975 EXPORT_SYMBOL(__napi_schedule); 5976 5977 /** 5978 * napi_schedule_prep - check if napi can be scheduled 5979 * @n: napi context 5980 * 5981 * Test if NAPI routine is already running, and if not mark 5982 * it as running. This is used as a condition variable to 5983 * insure only one NAPI poll instance runs. We also make 5984 * sure there is no pending NAPI disable. 5985 */ 5986 bool napi_schedule_prep(struct napi_struct *n) 5987 { 5988 unsigned long val, new; 5989 5990 do { 5991 val = READ_ONCE(n->state); 5992 if (unlikely(val & NAPIF_STATE_DISABLE)) 5993 return false; 5994 new = val | NAPIF_STATE_SCHED; 5995 5996 /* Sets STATE_MISSED bit if STATE_SCHED was already set 5997 * This was suggested by Alexander Duyck, as compiler 5998 * emits better code than : 5999 * if (val & NAPIF_STATE_SCHED) 6000 * new |= NAPIF_STATE_MISSED; 6001 */ 6002 new |= (val & NAPIF_STATE_SCHED) / NAPIF_STATE_SCHED * 6003 NAPIF_STATE_MISSED; 6004 } while (cmpxchg(&n->state, val, new) != val); 6005 6006 return !(val & NAPIF_STATE_SCHED); 6007 } 6008 EXPORT_SYMBOL(napi_schedule_prep); 6009 6010 /** 6011 * __napi_schedule_irqoff - schedule for receive 6012 * @n: entry to schedule 6013 * 6014 * Variant of __napi_schedule() assuming hard irqs are masked. 6015 * 6016 * On PREEMPT_RT enabled kernels this maps to __napi_schedule() 6017 * because the interrupt disabled assumption might not be true 6018 * due to force-threaded interrupts and spinlock substitution. 6019 */ 6020 void __napi_schedule_irqoff(struct napi_struct *n) 6021 { 6022 if (!IS_ENABLED(CONFIG_PREEMPT_RT)) 6023 ____napi_schedule(this_cpu_ptr(&softnet_data), n); 6024 else 6025 __napi_schedule(n); 6026 } 6027 EXPORT_SYMBOL(__napi_schedule_irqoff); 6028 6029 bool napi_complete_done(struct napi_struct *n, int work_done) 6030 { 6031 unsigned long flags, val, new, timeout = 0; 6032 bool ret = true; 6033 6034 /* 6035 * 1) Don't let napi dequeue from the cpu poll list 6036 * just in case its running on a different cpu. 6037 * 2) If we are busy polling, do nothing here, we have 6038 * the guarantee we will be called later. 6039 */ 6040 if (unlikely(n->state & (NAPIF_STATE_NPSVC | 6041 NAPIF_STATE_IN_BUSY_POLL))) 6042 return false; 6043 6044 if (work_done) { 6045 if (n->gro_bitmask) 6046 timeout = READ_ONCE(n->dev->gro_flush_timeout); 6047 n->defer_hard_irqs_count = READ_ONCE(n->dev->napi_defer_hard_irqs); 6048 } 6049 if (n->defer_hard_irqs_count > 0) { 6050 n->defer_hard_irqs_count--; 6051 timeout = READ_ONCE(n->dev->gro_flush_timeout); 6052 if (timeout) 6053 ret = false; 6054 } 6055 if (n->gro_bitmask) { 6056 /* When the NAPI instance uses a timeout and keeps postponing 6057 * it, we need to bound somehow the time packets are kept in 6058 * the GRO layer 6059 */ 6060 napi_gro_flush(n, !!timeout); 6061 } 6062 6063 gro_normal_list(n); 6064 6065 if (unlikely(!list_empty(&n->poll_list))) { 6066 /* If n->poll_list is not empty, we need to mask irqs */ 6067 local_irq_save(flags); 6068 list_del_init(&n->poll_list); 6069 local_irq_restore(flags); 6070 } 6071 6072 do { 6073 val = READ_ONCE(n->state); 6074 6075 WARN_ON_ONCE(!(val & NAPIF_STATE_SCHED)); 6076 6077 new = val & ~(NAPIF_STATE_MISSED | NAPIF_STATE_SCHED | 6078 NAPIF_STATE_SCHED_THREADED | 6079 NAPIF_STATE_PREFER_BUSY_POLL); 6080 6081 /* If STATE_MISSED was set, leave STATE_SCHED set, 6082 * because we will call napi->poll() one more time. 6083 * This C code was suggested by Alexander Duyck to help gcc. 6084 */ 6085 new |= (val & NAPIF_STATE_MISSED) / NAPIF_STATE_MISSED * 6086 NAPIF_STATE_SCHED; 6087 } while (cmpxchg(&n->state, val, new) != val); 6088 6089 if (unlikely(val & NAPIF_STATE_MISSED)) { 6090 __napi_schedule(n); 6091 return false; 6092 } 6093 6094 if (timeout) 6095 hrtimer_start(&n->timer, ns_to_ktime(timeout), 6096 HRTIMER_MODE_REL_PINNED); 6097 return ret; 6098 } 6099 EXPORT_SYMBOL(napi_complete_done); 6100 6101 /* must be called under rcu_read_lock(), as we dont take a reference */ 6102 static struct napi_struct *napi_by_id(unsigned int napi_id) 6103 { 6104 unsigned int hash = napi_id % HASH_SIZE(napi_hash); 6105 struct napi_struct *napi; 6106 6107 hlist_for_each_entry_rcu(napi, &napi_hash[hash], napi_hash_node) 6108 if (napi->napi_id == napi_id) 6109 return napi; 6110 6111 return NULL; 6112 } 6113 6114 #if defined(CONFIG_NET_RX_BUSY_POLL) 6115 6116 static void __busy_poll_stop(struct napi_struct *napi, bool skip_schedule) 6117 { 6118 if (!skip_schedule) { 6119 gro_normal_list(napi); 6120 __napi_schedule(napi); 6121 return; 6122 } 6123 6124 if (napi->gro_bitmask) { 6125 /* flush too old packets 6126 * If HZ < 1000, flush all packets. 6127 */ 6128 napi_gro_flush(napi, HZ >= 1000); 6129 } 6130 6131 gro_normal_list(napi); 6132 clear_bit(NAPI_STATE_SCHED, &napi->state); 6133 } 6134 6135 static void busy_poll_stop(struct napi_struct *napi, void *have_poll_lock, bool prefer_busy_poll, 6136 u16 budget) 6137 { 6138 bool skip_schedule = false; 6139 unsigned long timeout; 6140 int rc; 6141 6142 /* Busy polling means there is a high chance device driver hard irq 6143 * could not grab NAPI_STATE_SCHED, and that NAPI_STATE_MISSED was 6144 * set in napi_schedule_prep(). 6145 * Since we are about to call napi->poll() once more, we can safely 6146 * clear NAPI_STATE_MISSED. 6147 * 6148 * Note: x86 could use a single "lock and ..." instruction 6149 * to perform these two clear_bit() 6150 */ 6151 clear_bit(NAPI_STATE_MISSED, &napi->state); 6152 clear_bit(NAPI_STATE_IN_BUSY_POLL, &napi->state); 6153 6154 local_bh_disable(); 6155 6156 if (prefer_busy_poll) { 6157 napi->defer_hard_irqs_count = READ_ONCE(napi->dev->napi_defer_hard_irqs); 6158 timeout = READ_ONCE(napi->dev->gro_flush_timeout); 6159 if (napi->defer_hard_irqs_count && timeout) { 6160 hrtimer_start(&napi->timer, ns_to_ktime(timeout), HRTIMER_MODE_REL_PINNED); 6161 skip_schedule = true; 6162 } 6163 } 6164 6165 /* All we really want here is to re-enable device interrupts. 6166 * Ideally, a new ndo_busy_poll_stop() could avoid another round. 6167 */ 6168 rc = napi->poll(napi, budget); 6169 /* We can't gro_normal_list() here, because napi->poll() might have 6170 * rearmed the napi (napi_complete_done()) in which case it could 6171 * already be running on another CPU. 6172 */ 6173 trace_napi_poll(napi, rc, budget); 6174 netpoll_poll_unlock(have_poll_lock); 6175 if (rc == budget) 6176 __busy_poll_stop(napi, skip_schedule); 6177 local_bh_enable(); 6178 } 6179 6180 void napi_busy_loop(unsigned int napi_id, 6181 bool (*loop_end)(void *, unsigned long), 6182 void *loop_end_arg, bool prefer_busy_poll, u16 budget) 6183 { 6184 unsigned long start_time = loop_end ? busy_loop_current_time() : 0; 6185 int (*napi_poll)(struct napi_struct *napi, int budget); 6186 void *have_poll_lock = NULL; 6187 struct napi_struct *napi; 6188 6189 restart: 6190 napi_poll = NULL; 6191 6192 rcu_read_lock(); 6193 6194 napi = napi_by_id(napi_id); 6195 if (!napi) 6196 goto out; 6197 6198 preempt_disable(); 6199 for (;;) { 6200 int work = 0; 6201 6202 local_bh_disable(); 6203 if (!napi_poll) { 6204 unsigned long val = READ_ONCE(napi->state); 6205 6206 /* If multiple threads are competing for this napi, 6207 * we avoid dirtying napi->state as much as we can. 6208 */ 6209 if (val & (NAPIF_STATE_DISABLE | NAPIF_STATE_SCHED | 6210 NAPIF_STATE_IN_BUSY_POLL)) { 6211 if (prefer_busy_poll) 6212 set_bit(NAPI_STATE_PREFER_BUSY_POLL, &napi->state); 6213 goto count; 6214 } 6215 if (cmpxchg(&napi->state, val, 6216 val | NAPIF_STATE_IN_BUSY_POLL | 6217 NAPIF_STATE_SCHED) != val) { 6218 if (prefer_busy_poll) 6219 set_bit(NAPI_STATE_PREFER_BUSY_POLL, &napi->state); 6220 goto count; 6221 } 6222 have_poll_lock = netpoll_poll_lock(napi); 6223 napi_poll = napi->poll; 6224 } 6225 work = napi_poll(napi, budget); 6226 trace_napi_poll(napi, work, budget); 6227 gro_normal_list(napi); 6228 count: 6229 if (work > 0) 6230 __NET_ADD_STATS(dev_net(napi->dev), 6231 LINUX_MIB_BUSYPOLLRXPACKETS, work); 6232 local_bh_enable(); 6233 6234 if (!loop_end || loop_end(loop_end_arg, start_time)) 6235 break; 6236 6237 if (unlikely(need_resched())) { 6238 if (napi_poll) 6239 busy_poll_stop(napi, have_poll_lock, prefer_busy_poll, budget); 6240 preempt_enable(); 6241 rcu_read_unlock(); 6242 cond_resched(); 6243 if (loop_end(loop_end_arg, start_time)) 6244 return; 6245 goto restart; 6246 } 6247 cpu_relax(); 6248 } 6249 if (napi_poll) 6250 busy_poll_stop(napi, have_poll_lock, prefer_busy_poll, budget); 6251 preempt_enable(); 6252 out: 6253 rcu_read_unlock(); 6254 } 6255 EXPORT_SYMBOL(napi_busy_loop); 6256 6257 #endif /* CONFIG_NET_RX_BUSY_POLL */ 6258 6259 static void napi_hash_add(struct napi_struct *napi) 6260 { 6261 if (test_bit(NAPI_STATE_NO_BUSY_POLL, &napi->state)) 6262 return; 6263 6264 spin_lock(&napi_hash_lock); 6265 6266 /* 0..NR_CPUS range is reserved for sender_cpu use */ 6267 do { 6268 if (unlikely(++napi_gen_id < MIN_NAPI_ID)) 6269 napi_gen_id = MIN_NAPI_ID; 6270 } while (napi_by_id(napi_gen_id)); 6271 napi->napi_id = napi_gen_id; 6272 6273 hlist_add_head_rcu(&napi->napi_hash_node, 6274 &napi_hash[napi->napi_id % HASH_SIZE(napi_hash)]); 6275 6276 spin_unlock(&napi_hash_lock); 6277 } 6278 6279 /* Warning : caller is responsible to make sure rcu grace period 6280 * is respected before freeing memory containing @napi 6281 */ 6282 static void napi_hash_del(struct napi_struct *napi) 6283 { 6284 spin_lock(&napi_hash_lock); 6285 6286 hlist_del_init_rcu(&napi->napi_hash_node); 6287 6288 spin_unlock(&napi_hash_lock); 6289 } 6290 6291 static enum hrtimer_restart napi_watchdog(struct hrtimer *timer) 6292 { 6293 struct napi_struct *napi; 6294 6295 napi = container_of(timer, struct napi_struct, timer); 6296 6297 /* Note : we use a relaxed variant of napi_schedule_prep() not setting 6298 * NAPI_STATE_MISSED, since we do not react to a device IRQ. 6299 */ 6300 if (!napi_disable_pending(napi) && 6301 !test_and_set_bit(NAPI_STATE_SCHED, &napi->state)) { 6302 clear_bit(NAPI_STATE_PREFER_BUSY_POLL, &napi->state); 6303 __napi_schedule_irqoff(napi); 6304 } 6305 6306 return HRTIMER_NORESTART; 6307 } 6308 6309 static void init_gro_hash(struct napi_struct *napi) 6310 { 6311 int i; 6312 6313 for (i = 0; i < GRO_HASH_BUCKETS; i++) { 6314 INIT_LIST_HEAD(&napi->gro_hash[i].list); 6315 napi->gro_hash[i].count = 0; 6316 } 6317 napi->gro_bitmask = 0; 6318 } 6319 6320 int dev_set_threaded(struct net_device *dev, bool threaded) 6321 { 6322 struct napi_struct *napi; 6323 int err = 0; 6324 6325 if (dev->threaded == threaded) 6326 return 0; 6327 6328 if (threaded) { 6329 list_for_each_entry(napi, &dev->napi_list, dev_list) { 6330 if (!napi->thread) { 6331 err = napi_kthread_create(napi); 6332 if (err) { 6333 threaded = false; 6334 break; 6335 } 6336 } 6337 } 6338 } 6339 6340 dev->threaded = threaded; 6341 6342 /* Make sure kthread is created before THREADED bit 6343 * is set. 6344 */ 6345 smp_mb__before_atomic(); 6346 6347 /* Setting/unsetting threaded mode on a napi might not immediately 6348 * take effect, if the current napi instance is actively being 6349 * polled. In this case, the switch between threaded mode and 6350 * softirq mode will happen in the next round of napi_schedule(). 6351 * This should not cause hiccups/stalls to the live traffic. 6352 */ 6353 list_for_each_entry(napi, &dev->napi_list, dev_list) { 6354 if (threaded) 6355 set_bit(NAPI_STATE_THREADED, &napi->state); 6356 else 6357 clear_bit(NAPI_STATE_THREADED, &napi->state); 6358 } 6359 6360 return err; 6361 } 6362 EXPORT_SYMBOL(dev_set_threaded); 6363 6364 void netif_napi_add_weight(struct net_device *dev, struct napi_struct *napi, 6365 int (*poll)(struct napi_struct *, int), int weight) 6366 { 6367 if (WARN_ON(test_and_set_bit(NAPI_STATE_LISTED, &napi->state))) 6368 return; 6369 6370 INIT_LIST_HEAD(&napi->poll_list); 6371 INIT_HLIST_NODE(&napi->napi_hash_node); 6372 hrtimer_init(&napi->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_PINNED); 6373 napi->timer.function = napi_watchdog; 6374 init_gro_hash(napi); 6375 napi->skb = NULL; 6376 INIT_LIST_HEAD(&napi->rx_list); 6377 napi->rx_count = 0; 6378 napi->poll = poll; 6379 if (weight > NAPI_POLL_WEIGHT) 6380 netdev_err_once(dev, "%s() called with weight %d\n", __func__, 6381 weight); 6382 napi->weight = weight; 6383 napi->dev = dev; 6384 #ifdef CONFIG_NETPOLL 6385 napi->poll_owner = -1; 6386 #endif 6387 set_bit(NAPI_STATE_SCHED, &napi->state); 6388 set_bit(NAPI_STATE_NPSVC, &napi->state); 6389 list_add_rcu(&napi->dev_list, &dev->napi_list); 6390 napi_hash_add(napi); 6391 napi_get_frags_check(napi); 6392 /* Create kthread for this napi if dev->threaded is set. 6393 * Clear dev->threaded if kthread creation failed so that 6394 * threaded mode will not be enabled in napi_enable(). 6395 */ 6396 if (dev->threaded && napi_kthread_create(napi)) 6397 dev->threaded = 0; 6398 } 6399 EXPORT_SYMBOL(netif_napi_add_weight); 6400 6401 void napi_disable(struct napi_struct *n) 6402 { 6403 unsigned long val, new; 6404 6405 might_sleep(); 6406 set_bit(NAPI_STATE_DISABLE, &n->state); 6407 6408 for ( ; ; ) { 6409 val = READ_ONCE(n->state); 6410 if (val & (NAPIF_STATE_SCHED | NAPIF_STATE_NPSVC)) { 6411 usleep_range(20, 200); 6412 continue; 6413 } 6414 6415 new = val | NAPIF_STATE_SCHED | NAPIF_STATE_NPSVC; 6416 new &= ~(NAPIF_STATE_THREADED | NAPIF_STATE_PREFER_BUSY_POLL); 6417 6418 if (cmpxchg(&n->state, val, new) == val) 6419 break; 6420 } 6421 6422 hrtimer_cancel(&n->timer); 6423 6424 clear_bit(NAPI_STATE_DISABLE, &n->state); 6425 } 6426 EXPORT_SYMBOL(napi_disable); 6427 6428 /** 6429 * napi_enable - enable NAPI scheduling 6430 * @n: NAPI context 6431 * 6432 * Resume NAPI from being scheduled on this context. 6433 * Must be paired with napi_disable. 6434 */ 6435 void napi_enable(struct napi_struct *n) 6436 { 6437 unsigned long val, new; 6438 6439 do { 6440 val = READ_ONCE(n->state); 6441 BUG_ON(!test_bit(NAPI_STATE_SCHED, &val)); 6442 6443 new = val & ~(NAPIF_STATE_SCHED | NAPIF_STATE_NPSVC); 6444 if (n->dev->threaded && n->thread) 6445 new |= NAPIF_STATE_THREADED; 6446 } while (cmpxchg(&n->state, val, new) != val); 6447 } 6448 EXPORT_SYMBOL(napi_enable); 6449 6450 static void flush_gro_hash(struct napi_struct *napi) 6451 { 6452 int i; 6453 6454 for (i = 0; i < GRO_HASH_BUCKETS; i++) { 6455 struct sk_buff *skb, *n; 6456 6457 list_for_each_entry_safe(skb, n, &napi->gro_hash[i].list, list) 6458 kfree_skb(skb); 6459 napi->gro_hash[i].count = 0; 6460 } 6461 } 6462 6463 /* Must be called in process context */ 6464 void __netif_napi_del(struct napi_struct *napi) 6465 { 6466 if (!test_and_clear_bit(NAPI_STATE_LISTED, &napi->state)) 6467 return; 6468 6469 napi_hash_del(napi); 6470 list_del_rcu(&napi->dev_list); 6471 napi_free_frags(napi); 6472 6473 flush_gro_hash(napi); 6474 napi->gro_bitmask = 0; 6475 6476 if (napi->thread) { 6477 kthread_stop(napi->thread); 6478 napi->thread = NULL; 6479 } 6480 } 6481 EXPORT_SYMBOL(__netif_napi_del); 6482 6483 static int __napi_poll(struct napi_struct *n, bool *repoll) 6484 { 6485 int work, weight; 6486 6487 weight = n->weight; 6488 6489 /* This NAPI_STATE_SCHED test is for avoiding a race 6490 * with netpoll's poll_napi(). Only the entity which 6491 * obtains the lock and sees NAPI_STATE_SCHED set will 6492 * actually make the ->poll() call. Therefore we avoid 6493 * accidentally calling ->poll() when NAPI is not scheduled. 6494 */ 6495 work = 0; 6496 if (test_bit(NAPI_STATE_SCHED, &n->state)) { 6497 work = n->poll(n, weight); 6498 trace_napi_poll(n, work, weight); 6499 } 6500 6501 if (unlikely(work > weight)) 6502 netdev_err_once(n->dev, "NAPI poll function %pS returned %d, exceeding its budget of %d.\n", 6503 n->poll, work, weight); 6504 6505 if (likely(work < weight)) 6506 return work; 6507 6508 /* Drivers must not modify the NAPI state if they 6509 * consume the entire weight. In such cases this code 6510 * still "owns" the NAPI instance and therefore can 6511 * move the instance around on the list at-will. 6512 */ 6513 if (unlikely(napi_disable_pending(n))) { 6514 napi_complete(n); 6515 return work; 6516 } 6517 6518 /* The NAPI context has more processing work, but busy-polling 6519 * is preferred. Exit early. 6520 */ 6521 if (napi_prefer_busy_poll(n)) { 6522 if (napi_complete_done(n, work)) { 6523 /* If timeout is not set, we need to make sure 6524 * that the NAPI is re-scheduled. 6525 */ 6526 napi_schedule(n); 6527 } 6528 return work; 6529 } 6530 6531 if (n->gro_bitmask) { 6532 /* flush too old packets 6533 * If HZ < 1000, flush all packets. 6534 */ 6535 napi_gro_flush(n, HZ >= 1000); 6536 } 6537 6538 gro_normal_list(n); 6539 6540 /* Some drivers may have called napi_schedule 6541 * prior to exhausting their budget. 6542 */ 6543 if (unlikely(!list_empty(&n->poll_list))) { 6544 pr_warn_once("%s: Budget exhausted after napi rescheduled\n", 6545 n->dev ? n->dev->name : "backlog"); 6546 return work; 6547 } 6548 6549 *repoll = true; 6550 6551 return work; 6552 } 6553 6554 static int napi_poll(struct napi_struct *n, struct list_head *repoll) 6555 { 6556 bool do_repoll = false; 6557 void *have; 6558 int work; 6559 6560 list_del_init(&n->poll_list); 6561 6562 have = netpoll_poll_lock(n); 6563 6564 work = __napi_poll(n, &do_repoll); 6565 6566 if (do_repoll) 6567 list_add_tail(&n->poll_list, repoll); 6568 6569 netpoll_poll_unlock(have); 6570 6571 return work; 6572 } 6573 6574 static int napi_thread_wait(struct napi_struct *napi) 6575 { 6576 bool woken = false; 6577 6578 set_current_state(TASK_INTERRUPTIBLE); 6579 6580 while (!kthread_should_stop()) { 6581 /* Testing SCHED_THREADED bit here to make sure the current 6582 * kthread owns this napi and could poll on this napi. 6583 * Testing SCHED bit is not enough because SCHED bit might be 6584 * set by some other busy poll thread or by napi_disable(). 6585 */ 6586 if (test_bit(NAPI_STATE_SCHED_THREADED, &napi->state) || woken) { 6587 WARN_ON(!list_empty(&napi->poll_list)); 6588 __set_current_state(TASK_RUNNING); 6589 return 0; 6590 } 6591 6592 schedule(); 6593 /* woken being true indicates this thread owns this napi. */ 6594 woken = true; 6595 set_current_state(TASK_INTERRUPTIBLE); 6596 } 6597 __set_current_state(TASK_RUNNING); 6598 6599 return -1; 6600 } 6601 6602 static int napi_threaded_poll(void *data) 6603 { 6604 struct napi_struct *napi = data; 6605 void *have; 6606 6607 while (!napi_thread_wait(napi)) { 6608 for (;;) { 6609 bool repoll = false; 6610 6611 local_bh_disable(); 6612 6613 have = netpoll_poll_lock(napi); 6614 __napi_poll(napi, &repoll); 6615 netpoll_poll_unlock(have); 6616 6617 local_bh_enable(); 6618 6619 if (!repoll) 6620 break; 6621 6622 cond_resched(); 6623 } 6624 } 6625 return 0; 6626 } 6627 6628 static void skb_defer_free_flush(struct softnet_data *sd) 6629 { 6630 struct sk_buff *skb, *next; 6631 unsigned long flags; 6632 6633 /* Paired with WRITE_ONCE() in skb_attempt_defer_free() */ 6634 if (!READ_ONCE(sd->defer_list)) 6635 return; 6636 6637 spin_lock_irqsave(&sd->defer_lock, flags); 6638 skb = sd->defer_list; 6639 sd->defer_list = NULL; 6640 sd->defer_count = 0; 6641 spin_unlock_irqrestore(&sd->defer_lock, flags); 6642 6643 while (skb != NULL) { 6644 next = skb->next; 6645 napi_consume_skb(skb, 1); 6646 skb = next; 6647 } 6648 } 6649 6650 static __latent_entropy void net_rx_action(struct softirq_action *h) 6651 { 6652 struct softnet_data *sd = this_cpu_ptr(&softnet_data); 6653 unsigned long time_limit = jiffies + 6654 usecs_to_jiffies(READ_ONCE(netdev_budget_usecs)); 6655 int budget = READ_ONCE(netdev_budget); 6656 LIST_HEAD(list); 6657 LIST_HEAD(repoll); 6658 6659 local_irq_disable(); 6660 list_splice_init(&sd->poll_list, &list); 6661 local_irq_enable(); 6662 6663 for (;;) { 6664 struct napi_struct *n; 6665 6666 skb_defer_free_flush(sd); 6667 6668 if (list_empty(&list)) { 6669 if (!sd_has_rps_ipi_waiting(sd) && list_empty(&repoll)) 6670 goto end; 6671 break; 6672 } 6673 6674 n = list_first_entry(&list, struct napi_struct, poll_list); 6675 budget -= napi_poll(n, &repoll); 6676 6677 /* If softirq window is exhausted then punt. 6678 * Allow this to run for 2 jiffies since which will allow 6679 * an average latency of 1.5/HZ. 6680 */ 6681 if (unlikely(budget <= 0 || 6682 time_after_eq(jiffies, time_limit))) { 6683 sd->time_squeeze++; 6684 break; 6685 } 6686 } 6687 6688 local_irq_disable(); 6689 6690 list_splice_tail_init(&sd->poll_list, &list); 6691 list_splice_tail(&repoll, &list); 6692 list_splice(&list, &sd->poll_list); 6693 if (!list_empty(&sd->poll_list)) 6694 __raise_softirq_irqoff(NET_RX_SOFTIRQ); 6695 6696 net_rps_action_and_irq_enable(sd); 6697 end:; 6698 } 6699 6700 struct netdev_adjacent { 6701 struct net_device *dev; 6702 netdevice_tracker dev_tracker; 6703 6704 /* upper master flag, there can only be one master device per list */ 6705 bool master; 6706 6707 /* lookup ignore flag */ 6708 bool ignore; 6709 6710 /* counter for the number of times this device was added to us */ 6711 u16 ref_nr; 6712 6713 /* private field for the users */ 6714 void *private; 6715 6716 struct list_head list; 6717 struct rcu_head rcu; 6718 }; 6719 6720 static struct netdev_adjacent *__netdev_find_adj(struct net_device *adj_dev, 6721 struct list_head *adj_list) 6722 { 6723 struct netdev_adjacent *adj; 6724 6725 list_for_each_entry(adj, adj_list, list) { 6726 if (adj->dev == adj_dev) 6727 return adj; 6728 } 6729 return NULL; 6730 } 6731 6732 static int ____netdev_has_upper_dev(struct net_device *upper_dev, 6733 struct netdev_nested_priv *priv) 6734 { 6735 struct net_device *dev = (struct net_device *)priv->data; 6736 6737 return upper_dev == dev; 6738 } 6739 6740 /** 6741 * netdev_has_upper_dev - Check if device is linked to an upper device 6742 * @dev: device 6743 * @upper_dev: upper device to check 6744 * 6745 * Find out if a device is linked to specified upper device and return true 6746 * in case it is. Note that this checks only immediate upper device, 6747 * not through a complete stack of devices. The caller must hold the RTNL lock. 6748 */ 6749 bool netdev_has_upper_dev(struct net_device *dev, 6750 struct net_device *upper_dev) 6751 { 6752 struct netdev_nested_priv priv = { 6753 .data = (void *)upper_dev, 6754 }; 6755 6756 ASSERT_RTNL(); 6757 6758 return netdev_walk_all_upper_dev_rcu(dev, ____netdev_has_upper_dev, 6759 &priv); 6760 } 6761 EXPORT_SYMBOL(netdev_has_upper_dev); 6762 6763 /** 6764 * netdev_has_upper_dev_all_rcu - Check if device is linked to an upper device 6765 * @dev: device 6766 * @upper_dev: upper device to check 6767 * 6768 * Find out if a device is linked to specified upper device and return true 6769 * in case it is. Note that this checks the entire upper device chain. 6770 * The caller must hold rcu lock. 6771 */ 6772 6773 bool netdev_has_upper_dev_all_rcu(struct net_device *dev, 6774 struct net_device *upper_dev) 6775 { 6776 struct netdev_nested_priv priv = { 6777 .data = (void *)upper_dev, 6778 }; 6779 6780 return !!netdev_walk_all_upper_dev_rcu(dev, ____netdev_has_upper_dev, 6781 &priv); 6782 } 6783 EXPORT_SYMBOL(netdev_has_upper_dev_all_rcu); 6784 6785 /** 6786 * netdev_has_any_upper_dev - Check if device is linked to some device 6787 * @dev: device 6788 * 6789 * Find out if a device is linked to an upper device and return true in case 6790 * it is. The caller must hold the RTNL lock. 6791 */ 6792 bool netdev_has_any_upper_dev(struct net_device *dev) 6793 { 6794 ASSERT_RTNL(); 6795 6796 return !list_empty(&dev->adj_list.upper); 6797 } 6798 EXPORT_SYMBOL(netdev_has_any_upper_dev); 6799 6800 /** 6801 * netdev_master_upper_dev_get - Get master upper device 6802 * @dev: device 6803 * 6804 * Find a master upper device and return pointer to it or NULL in case 6805 * it's not there. The caller must hold the RTNL lock. 6806 */ 6807 struct net_device *netdev_master_upper_dev_get(struct net_device *dev) 6808 { 6809 struct netdev_adjacent *upper; 6810 6811 ASSERT_RTNL(); 6812 6813 if (list_empty(&dev->adj_list.upper)) 6814 return NULL; 6815 6816 upper = list_first_entry(&dev->adj_list.upper, 6817 struct netdev_adjacent, list); 6818 if (likely(upper->master)) 6819 return upper->dev; 6820 return NULL; 6821 } 6822 EXPORT_SYMBOL(netdev_master_upper_dev_get); 6823 6824 static struct net_device *__netdev_master_upper_dev_get(struct net_device *dev) 6825 { 6826 struct netdev_adjacent *upper; 6827 6828 ASSERT_RTNL(); 6829 6830 if (list_empty(&dev->adj_list.upper)) 6831 return NULL; 6832 6833 upper = list_first_entry(&dev->adj_list.upper, 6834 struct netdev_adjacent, list); 6835 if (likely(upper->master) && !upper->ignore) 6836 return upper->dev; 6837 return NULL; 6838 } 6839 6840 /** 6841 * netdev_has_any_lower_dev - Check if device is linked to some device 6842 * @dev: device 6843 * 6844 * Find out if a device is linked to a lower device and return true in case 6845 * it is. The caller must hold the RTNL lock. 6846 */ 6847 static bool netdev_has_any_lower_dev(struct net_device *dev) 6848 { 6849 ASSERT_RTNL(); 6850 6851 return !list_empty(&dev->adj_list.lower); 6852 } 6853 6854 void *netdev_adjacent_get_private(struct list_head *adj_list) 6855 { 6856 struct netdev_adjacent *adj; 6857 6858 adj = list_entry(adj_list, struct netdev_adjacent, list); 6859 6860 return adj->private; 6861 } 6862 EXPORT_SYMBOL(netdev_adjacent_get_private); 6863 6864 /** 6865 * netdev_upper_get_next_dev_rcu - Get the next dev from upper list 6866 * @dev: device 6867 * @iter: list_head ** of the current position 6868 * 6869 * Gets the next device from the dev's upper list, starting from iter 6870 * position. The caller must hold RCU read lock. 6871 */ 6872 struct net_device *netdev_upper_get_next_dev_rcu(struct net_device *dev, 6873 struct list_head **iter) 6874 { 6875 struct netdev_adjacent *upper; 6876 6877 WARN_ON_ONCE(!rcu_read_lock_held() && !lockdep_rtnl_is_held()); 6878 6879 upper = list_entry_rcu((*iter)->next, struct netdev_adjacent, list); 6880 6881 if (&upper->list == &dev->adj_list.upper) 6882 return NULL; 6883 6884 *iter = &upper->list; 6885 6886 return upper->dev; 6887 } 6888 EXPORT_SYMBOL(netdev_upper_get_next_dev_rcu); 6889 6890 static struct net_device *__netdev_next_upper_dev(struct net_device *dev, 6891 struct list_head **iter, 6892 bool *ignore) 6893 { 6894 struct netdev_adjacent *upper; 6895 6896 upper = list_entry((*iter)->next, struct netdev_adjacent, list); 6897 6898 if (&upper->list == &dev->adj_list.upper) 6899 return NULL; 6900 6901 *iter = &upper->list; 6902 *ignore = upper->ignore; 6903 6904 return upper->dev; 6905 } 6906 6907 static struct net_device *netdev_next_upper_dev_rcu(struct net_device *dev, 6908 struct list_head **iter) 6909 { 6910 struct netdev_adjacent *upper; 6911 6912 WARN_ON_ONCE(!rcu_read_lock_held() && !lockdep_rtnl_is_held()); 6913 6914 upper = list_entry_rcu((*iter)->next, struct netdev_adjacent, list); 6915 6916 if (&upper->list == &dev->adj_list.upper) 6917 return NULL; 6918 6919 *iter = &upper->list; 6920 6921 return upper->dev; 6922 } 6923 6924 static int __netdev_walk_all_upper_dev(struct net_device *dev, 6925 int (*fn)(struct net_device *dev, 6926 struct netdev_nested_priv *priv), 6927 struct netdev_nested_priv *priv) 6928 { 6929 struct net_device *udev, *next, *now, *dev_stack[MAX_NEST_DEV + 1]; 6930 struct list_head *niter, *iter, *iter_stack[MAX_NEST_DEV + 1]; 6931 int ret, cur = 0; 6932 bool ignore; 6933 6934 now = dev; 6935 iter = &dev->adj_list.upper; 6936 6937 while (1) { 6938 if (now != dev) { 6939 ret = fn(now, priv); 6940 if (ret) 6941 return ret; 6942 } 6943 6944 next = NULL; 6945 while (1) { 6946 udev = __netdev_next_upper_dev(now, &iter, &ignore); 6947 if (!udev) 6948 break; 6949 if (ignore) 6950 continue; 6951 6952 next = udev; 6953 niter = &udev->adj_list.upper; 6954 dev_stack[cur] = now; 6955 iter_stack[cur++] = iter; 6956 break; 6957 } 6958 6959 if (!next) { 6960 if (!cur) 6961 return 0; 6962 next = dev_stack[--cur]; 6963 niter = iter_stack[cur]; 6964 } 6965 6966 now = next; 6967 iter = niter; 6968 } 6969 6970 return 0; 6971 } 6972 6973 int netdev_walk_all_upper_dev_rcu(struct net_device *dev, 6974 int (*fn)(struct net_device *dev, 6975 struct netdev_nested_priv *priv), 6976 struct netdev_nested_priv *priv) 6977 { 6978 struct net_device *udev, *next, *now, *dev_stack[MAX_NEST_DEV + 1]; 6979 struct list_head *niter, *iter, *iter_stack[MAX_NEST_DEV + 1]; 6980 int ret, cur = 0; 6981 6982 now = dev; 6983 iter = &dev->adj_list.upper; 6984 6985 while (1) { 6986 if (now != dev) { 6987 ret = fn(now, priv); 6988 if (ret) 6989 return ret; 6990 } 6991 6992 next = NULL; 6993 while (1) { 6994 udev = netdev_next_upper_dev_rcu(now, &iter); 6995 if (!udev) 6996 break; 6997 6998 next = udev; 6999 niter = &udev->adj_list.upper; 7000 dev_stack[cur] = now; 7001 iter_stack[cur++] = iter; 7002 break; 7003 } 7004 7005 if (!next) { 7006 if (!cur) 7007 return 0; 7008 next = dev_stack[--cur]; 7009 niter = iter_stack[cur]; 7010 } 7011 7012 now = next; 7013 iter = niter; 7014 } 7015 7016 return 0; 7017 } 7018 EXPORT_SYMBOL_GPL(netdev_walk_all_upper_dev_rcu); 7019 7020 static bool __netdev_has_upper_dev(struct net_device *dev, 7021 struct net_device *upper_dev) 7022 { 7023 struct netdev_nested_priv priv = { 7024 .flags = 0, 7025 .data = (void *)upper_dev, 7026 }; 7027 7028 ASSERT_RTNL(); 7029 7030 return __netdev_walk_all_upper_dev(dev, ____netdev_has_upper_dev, 7031 &priv); 7032 } 7033 7034 /** 7035 * netdev_lower_get_next_private - Get the next ->private from the 7036 * lower neighbour list 7037 * @dev: device 7038 * @iter: list_head ** of the current position 7039 * 7040 * Gets the next netdev_adjacent->private from the dev's lower neighbour 7041 * list, starting from iter position. The caller must hold either hold the 7042 * RTNL lock or its own locking that guarantees that the neighbour lower 7043 * list will remain unchanged. 7044 */ 7045 void *netdev_lower_get_next_private(struct net_device *dev, 7046 struct list_head **iter) 7047 { 7048 struct netdev_adjacent *lower; 7049 7050 lower = list_entry(*iter, struct netdev_adjacent, list); 7051 7052 if (&lower->list == &dev->adj_list.lower) 7053 return NULL; 7054 7055 *iter = lower->list.next; 7056 7057 return lower->private; 7058 } 7059 EXPORT_SYMBOL(netdev_lower_get_next_private); 7060 7061 /** 7062 * netdev_lower_get_next_private_rcu - Get the next ->private from the 7063 * lower neighbour list, RCU 7064 * variant 7065 * @dev: device 7066 * @iter: list_head ** of the current position 7067 * 7068 * Gets the next netdev_adjacent->private from the dev's lower neighbour 7069 * list, starting from iter position. The caller must hold RCU read lock. 7070 */ 7071 void *netdev_lower_get_next_private_rcu(struct net_device *dev, 7072 struct list_head **iter) 7073 { 7074 struct netdev_adjacent *lower; 7075 7076 WARN_ON_ONCE(!rcu_read_lock_held() && !rcu_read_lock_bh_held()); 7077 7078 lower = list_entry_rcu((*iter)->next, struct netdev_adjacent, list); 7079 7080 if (&lower->list == &dev->adj_list.lower) 7081 return NULL; 7082 7083 *iter = &lower->list; 7084 7085 return lower->private; 7086 } 7087 EXPORT_SYMBOL(netdev_lower_get_next_private_rcu); 7088 7089 /** 7090 * netdev_lower_get_next - Get the next device from the lower neighbour 7091 * list 7092 * @dev: device 7093 * @iter: list_head ** of the current position 7094 * 7095 * Gets the next netdev_adjacent from the dev's lower neighbour 7096 * list, starting from iter position. The caller must hold RTNL lock or 7097 * its own locking that guarantees that the neighbour lower 7098 * list will remain unchanged. 7099 */ 7100 void *netdev_lower_get_next(struct net_device *dev, struct list_head **iter) 7101 { 7102 struct netdev_adjacent *lower; 7103 7104 lower = list_entry(*iter, struct netdev_adjacent, list); 7105 7106 if (&lower->list == &dev->adj_list.lower) 7107 return NULL; 7108 7109 *iter = lower->list.next; 7110 7111 return lower->dev; 7112 } 7113 EXPORT_SYMBOL(netdev_lower_get_next); 7114 7115 static struct net_device *netdev_next_lower_dev(struct net_device *dev, 7116 struct list_head **iter) 7117 { 7118 struct netdev_adjacent *lower; 7119 7120 lower = list_entry((*iter)->next, struct netdev_adjacent, list); 7121 7122 if (&lower->list == &dev->adj_list.lower) 7123 return NULL; 7124 7125 *iter = &lower->list; 7126 7127 return lower->dev; 7128 } 7129 7130 static struct net_device *__netdev_next_lower_dev(struct net_device *dev, 7131 struct list_head **iter, 7132 bool *ignore) 7133 { 7134 struct netdev_adjacent *lower; 7135 7136 lower = list_entry((*iter)->next, struct netdev_adjacent, list); 7137 7138 if (&lower->list == &dev->adj_list.lower) 7139 return NULL; 7140 7141 *iter = &lower->list; 7142 *ignore = lower->ignore; 7143 7144 return lower->dev; 7145 } 7146 7147 int netdev_walk_all_lower_dev(struct net_device *dev, 7148 int (*fn)(struct net_device *dev, 7149 struct netdev_nested_priv *priv), 7150 struct netdev_nested_priv *priv) 7151 { 7152 struct net_device *ldev, *next, *now, *dev_stack[MAX_NEST_DEV + 1]; 7153 struct list_head *niter, *iter, *iter_stack[MAX_NEST_DEV + 1]; 7154 int ret, cur = 0; 7155 7156 now = dev; 7157 iter = &dev->adj_list.lower; 7158 7159 while (1) { 7160 if (now != dev) { 7161 ret = fn(now, priv); 7162 if (ret) 7163 return ret; 7164 } 7165 7166 next = NULL; 7167 while (1) { 7168 ldev = netdev_next_lower_dev(now, &iter); 7169 if (!ldev) 7170 break; 7171 7172 next = ldev; 7173 niter = &ldev->adj_list.lower; 7174 dev_stack[cur] = now; 7175 iter_stack[cur++] = iter; 7176 break; 7177 } 7178 7179 if (!next) { 7180 if (!cur) 7181 return 0; 7182 next = dev_stack[--cur]; 7183 niter = iter_stack[cur]; 7184 } 7185 7186 now = next; 7187 iter = niter; 7188 } 7189 7190 return 0; 7191 } 7192 EXPORT_SYMBOL_GPL(netdev_walk_all_lower_dev); 7193 7194 static int __netdev_walk_all_lower_dev(struct net_device *dev, 7195 int (*fn)(struct net_device *dev, 7196 struct netdev_nested_priv *priv), 7197 struct netdev_nested_priv *priv) 7198 { 7199 struct net_device *ldev, *next, *now, *dev_stack[MAX_NEST_DEV + 1]; 7200 struct list_head *niter, *iter, *iter_stack[MAX_NEST_DEV + 1]; 7201 int ret, cur = 0; 7202 bool ignore; 7203 7204 now = dev; 7205 iter = &dev->adj_list.lower; 7206 7207 while (1) { 7208 if (now != dev) { 7209 ret = fn(now, priv); 7210 if (ret) 7211 return ret; 7212 } 7213 7214 next = NULL; 7215 while (1) { 7216 ldev = __netdev_next_lower_dev(now, &iter, &ignore); 7217 if (!ldev) 7218 break; 7219 if (ignore) 7220 continue; 7221 7222 next = ldev; 7223 niter = &ldev->adj_list.lower; 7224 dev_stack[cur] = now; 7225 iter_stack[cur++] = iter; 7226 break; 7227 } 7228 7229 if (!next) { 7230 if (!cur) 7231 return 0; 7232 next = dev_stack[--cur]; 7233 niter = iter_stack[cur]; 7234 } 7235 7236 now = next; 7237 iter = niter; 7238 } 7239 7240 return 0; 7241 } 7242 7243 struct net_device *netdev_next_lower_dev_rcu(struct net_device *dev, 7244 struct list_head **iter) 7245 { 7246 struct netdev_adjacent *lower; 7247 7248 lower = list_entry_rcu((*iter)->next, struct netdev_adjacent, list); 7249 if (&lower->list == &dev->adj_list.lower) 7250 return NULL; 7251 7252 *iter = &lower->list; 7253 7254 return lower->dev; 7255 } 7256 EXPORT_SYMBOL(netdev_next_lower_dev_rcu); 7257 7258 static u8 __netdev_upper_depth(struct net_device *dev) 7259 { 7260 struct net_device *udev; 7261 struct list_head *iter; 7262 u8 max_depth = 0; 7263 bool ignore; 7264 7265 for (iter = &dev->adj_list.upper, 7266 udev = __netdev_next_upper_dev(dev, &iter, &ignore); 7267 udev; 7268 udev = __netdev_next_upper_dev(dev, &iter, &ignore)) { 7269 if (ignore) 7270 continue; 7271 if (max_depth < udev->upper_level) 7272 max_depth = udev->upper_level; 7273 } 7274 7275 return max_depth; 7276 } 7277 7278 static u8 __netdev_lower_depth(struct net_device *dev) 7279 { 7280 struct net_device *ldev; 7281 struct list_head *iter; 7282 u8 max_depth = 0; 7283 bool ignore; 7284 7285 for (iter = &dev->adj_list.lower, 7286 ldev = __netdev_next_lower_dev(dev, &iter, &ignore); 7287 ldev; 7288 ldev = __netdev_next_lower_dev(dev, &iter, &ignore)) { 7289 if (ignore) 7290 continue; 7291 if (max_depth < ldev->lower_level) 7292 max_depth = ldev->lower_level; 7293 } 7294 7295 return max_depth; 7296 } 7297 7298 static int __netdev_update_upper_level(struct net_device *dev, 7299 struct netdev_nested_priv *__unused) 7300 { 7301 dev->upper_level = __netdev_upper_depth(dev) + 1; 7302 return 0; 7303 } 7304 7305 #ifdef CONFIG_LOCKDEP 7306 static LIST_HEAD(net_unlink_list); 7307 7308 static void net_unlink_todo(struct net_device *dev) 7309 { 7310 if (list_empty(&dev->unlink_list)) 7311 list_add_tail(&dev->unlink_list, &net_unlink_list); 7312 } 7313 #endif 7314 7315 static int __netdev_update_lower_level(struct net_device *dev, 7316 struct netdev_nested_priv *priv) 7317 { 7318 dev->lower_level = __netdev_lower_depth(dev) + 1; 7319 7320 #ifdef CONFIG_LOCKDEP 7321 if (!priv) 7322 return 0; 7323 7324 if (priv->flags & NESTED_SYNC_IMM) 7325 dev->nested_level = dev->lower_level - 1; 7326 if (priv->flags & NESTED_SYNC_TODO) 7327 net_unlink_todo(dev); 7328 #endif 7329 return 0; 7330 } 7331 7332 int netdev_walk_all_lower_dev_rcu(struct net_device *dev, 7333 int (*fn)(struct net_device *dev, 7334 struct netdev_nested_priv *priv), 7335 struct netdev_nested_priv *priv) 7336 { 7337 struct net_device *ldev, *next, *now, *dev_stack[MAX_NEST_DEV + 1]; 7338 struct list_head *niter, *iter, *iter_stack[MAX_NEST_DEV + 1]; 7339 int ret, cur = 0; 7340 7341 now = dev; 7342 iter = &dev->adj_list.lower; 7343 7344 while (1) { 7345 if (now != dev) { 7346 ret = fn(now, priv); 7347 if (ret) 7348 return ret; 7349 } 7350 7351 next = NULL; 7352 while (1) { 7353 ldev = netdev_next_lower_dev_rcu(now, &iter); 7354 if (!ldev) 7355 break; 7356 7357 next = ldev; 7358 niter = &ldev->adj_list.lower; 7359 dev_stack[cur] = now; 7360 iter_stack[cur++] = iter; 7361 break; 7362 } 7363 7364 if (!next) { 7365 if (!cur) 7366 return 0; 7367 next = dev_stack[--cur]; 7368 niter = iter_stack[cur]; 7369 } 7370 7371 now = next; 7372 iter = niter; 7373 } 7374 7375 return 0; 7376 } 7377 EXPORT_SYMBOL_GPL(netdev_walk_all_lower_dev_rcu); 7378 7379 /** 7380 * netdev_lower_get_first_private_rcu - Get the first ->private from the 7381 * lower neighbour list, RCU 7382 * variant 7383 * @dev: device 7384 * 7385 * Gets the first netdev_adjacent->private from the dev's lower neighbour 7386 * list. The caller must hold RCU read lock. 7387 */ 7388 void *netdev_lower_get_first_private_rcu(struct net_device *dev) 7389 { 7390 struct netdev_adjacent *lower; 7391 7392 lower = list_first_or_null_rcu(&dev->adj_list.lower, 7393 struct netdev_adjacent, list); 7394 if (lower) 7395 return lower->private; 7396 return NULL; 7397 } 7398 EXPORT_SYMBOL(netdev_lower_get_first_private_rcu); 7399 7400 /** 7401 * netdev_master_upper_dev_get_rcu - Get master upper device 7402 * @dev: device 7403 * 7404 * Find a master upper device and return pointer to it or NULL in case 7405 * it's not there. The caller must hold the RCU read lock. 7406 */ 7407 struct net_device *netdev_master_upper_dev_get_rcu(struct net_device *dev) 7408 { 7409 struct netdev_adjacent *upper; 7410 7411 upper = list_first_or_null_rcu(&dev->adj_list.upper, 7412 struct netdev_adjacent, list); 7413 if (upper && likely(upper->master)) 7414 return upper->dev; 7415 return NULL; 7416 } 7417 EXPORT_SYMBOL(netdev_master_upper_dev_get_rcu); 7418 7419 static int netdev_adjacent_sysfs_add(struct net_device *dev, 7420 struct net_device *adj_dev, 7421 struct list_head *dev_list) 7422 { 7423 char linkname[IFNAMSIZ+7]; 7424 7425 sprintf(linkname, dev_list == &dev->adj_list.upper ? 7426 "upper_%s" : "lower_%s", adj_dev->name); 7427 return sysfs_create_link(&(dev->dev.kobj), &(adj_dev->dev.kobj), 7428 linkname); 7429 } 7430 static void netdev_adjacent_sysfs_del(struct net_device *dev, 7431 char *name, 7432 struct list_head *dev_list) 7433 { 7434 char linkname[IFNAMSIZ+7]; 7435 7436 sprintf(linkname, dev_list == &dev->adj_list.upper ? 7437 "upper_%s" : "lower_%s", name); 7438 sysfs_remove_link(&(dev->dev.kobj), linkname); 7439 } 7440 7441 static inline bool netdev_adjacent_is_neigh_list(struct net_device *dev, 7442 struct net_device *adj_dev, 7443 struct list_head *dev_list) 7444 { 7445 return (dev_list == &dev->adj_list.upper || 7446 dev_list == &dev->adj_list.lower) && 7447 net_eq(dev_net(dev), dev_net(adj_dev)); 7448 } 7449 7450 static int __netdev_adjacent_dev_insert(struct net_device *dev, 7451 struct net_device *adj_dev, 7452 struct list_head *dev_list, 7453 void *private, bool master) 7454 { 7455 struct netdev_adjacent *adj; 7456 int ret; 7457 7458 adj = __netdev_find_adj(adj_dev, dev_list); 7459 7460 if (adj) { 7461 adj->ref_nr += 1; 7462 pr_debug("Insert adjacency: dev %s adj_dev %s adj->ref_nr %d\n", 7463 dev->name, adj_dev->name, adj->ref_nr); 7464 7465 return 0; 7466 } 7467 7468 adj = kmalloc(sizeof(*adj), GFP_KERNEL); 7469 if (!adj) 7470 return -ENOMEM; 7471 7472 adj->dev = adj_dev; 7473 adj->master = master; 7474 adj->ref_nr = 1; 7475 adj->private = private; 7476 adj->ignore = false; 7477 netdev_hold(adj_dev, &adj->dev_tracker, GFP_KERNEL); 7478 7479 pr_debug("Insert adjacency: dev %s adj_dev %s adj->ref_nr %d; dev_hold on %s\n", 7480 dev->name, adj_dev->name, adj->ref_nr, adj_dev->name); 7481 7482 if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list)) { 7483 ret = netdev_adjacent_sysfs_add(dev, adj_dev, dev_list); 7484 if (ret) 7485 goto free_adj; 7486 } 7487 7488 /* Ensure that master link is always the first item in list. */ 7489 if (master) { 7490 ret = sysfs_create_link(&(dev->dev.kobj), 7491 &(adj_dev->dev.kobj), "master"); 7492 if (ret) 7493 goto remove_symlinks; 7494 7495 list_add_rcu(&adj->list, dev_list); 7496 } else { 7497 list_add_tail_rcu(&adj->list, dev_list); 7498 } 7499 7500 return 0; 7501 7502 remove_symlinks: 7503 if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list)) 7504 netdev_adjacent_sysfs_del(dev, adj_dev->name, dev_list); 7505 free_adj: 7506 netdev_put(adj_dev, &adj->dev_tracker); 7507 kfree(adj); 7508 7509 return ret; 7510 } 7511 7512 static void __netdev_adjacent_dev_remove(struct net_device *dev, 7513 struct net_device *adj_dev, 7514 u16 ref_nr, 7515 struct list_head *dev_list) 7516 { 7517 struct netdev_adjacent *adj; 7518 7519 pr_debug("Remove adjacency: dev %s adj_dev %s ref_nr %d\n", 7520 dev->name, adj_dev->name, ref_nr); 7521 7522 adj = __netdev_find_adj(adj_dev, dev_list); 7523 7524 if (!adj) { 7525 pr_err("Adjacency does not exist for device %s from %s\n", 7526 dev->name, adj_dev->name); 7527 WARN_ON(1); 7528 return; 7529 } 7530 7531 if (adj->ref_nr > ref_nr) { 7532 pr_debug("adjacency: %s to %s ref_nr - %d = %d\n", 7533 dev->name, adj_dev->name, ref_nr, 7534 adj->ref_nr - ref_nr); 7535 adj->ref_nr -= ref_nr; 7536 return; 7537 } 7538 7539 if (adj->master) 7540 sysfs_remove_link(&(dev->dev.kobj), "master"); 7541 7542 if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list)) 7543 netdev_adjacent_sysfs_del(dev, adj_dev->name, dev_list); 7544 7545 list_del_rcu(&adj->list); 7546 pr_debug("adjacency: dev_put for %s, because link removed from %s to %s\n", 7547 adj_dev->name, dev->name, adj_dev->name); 7548 netdev_put(adj_dev, &adj->dev_tracker); 7549 kfree_rcu(adj, rcu); 7550 } 7551 7552 static int __netdev_adjacent_dev_link_lists(struct net_device *dev, 7553 struct net_device *upper_dev, 7554 struct list_head *up_list, 7555 struct list_head *down_list, 7556 void *private, bool master) 7557 { 7558 int ret; 7559 7560 ret = __netdev_adjacent_dev_insert(dev, upper_dev, up_list, 7561 private, master); 7562 if (ret) 7563 return ret; 7564 7565 ret = __netdev_adjacent_dev_insert(upper_dev, dev, down_list, 7566 private, false); 7567 if (ret) { 7568 __netdev_adjacent_dev_remove(dev, upper_dev, 1, up_list); 7569 return ret; 7570 } 7571 7572 return 0; 7573 } 7574 7575 static void __netdev_adjacent_dev_unlink_lists(struct net_device *dev, 7576 struct net_device *upper_dev, 7577 u16 ref_nr, 7578 struct list_head *up_list, 7579 struct list_head *down_list) 7580 { 7581 __netdev_adjacent_dev_remove(dev, upper_dev, ref_nr, up_list); 7582 __netdev_adjacent_dev_remove(upper_dev, dev, ref_nr, down_list); 7583 } 7584 7585 static int __netdev_adjacent_dev_link_neighbour(struct net_device *dev, 7586 struct net_device *upper_dev, 7587 void *private, bool master) 7588 { 7589 return __netdev_adjacent_dev_link_lists(dev, upper_dev, 7590 &dev->adj_list.upper, 7591 &upper_dev->adj_list.lower, 7592 private, master); 7593 } 7594 7595 static void __netdev_adjacent_dev_unlink_neighbour(struct net_device *dev, 7596 struct net_device *upper_dev) 7597 { 7598 __netdev_adjacent_dev_unlink_lists(dev, upper_dev, 1, 7599 &dev->adj_list.upper, 7600 &upper_dev->adj_list.lower); 7601 } 7602 7603 static int __netdev_upper_dev_link(struct net_device *dev, 7604 struct net_device *upper_dev, bool master, 7605 void *upper_priv, void *upper_info, 7606 struct netdev_nested_priv *priv, 7607 struct netlink_ext_ack *extack) 7608 { 7609 struct netdev_notifier_changeupper_info changeupper_info = { 7610 .info = { 7611 .dev = dev, 7612 .extack = extack, 7613 }, 7614 .upper_dev = upper_dev, 7615 .master = master, 7616 .linking = true, 7617 .upper_info = upper_info, 7618 }; 7619 struct net_device *master_dev; 7620 int ret = 0; 7621 7622 ASSERT_RTNL(); 7623 7624 if (dev == upper_dev) 7625 return -EBUSY; 7626 7627 /* To prevent loops, check if dev is not upper device to upper_dev. */ 7628 if (__netdev_has_upper_dev(upper_dev, dev)) 7629 return -EBUSY; 7630 7631 if ((dev->lower_level + upper_dev->upper_level) > MAX_NEST_DEV) 7632 return -EMLINK; 7633 7634 if (!master) { 7635 if (__netdev_has_upper_dev(dev, upper_dev)) 7636 return -EEXIST; 7637 } else { 7638 master_dev = __netdev_master_upper_dev_get(dev); 7639 if (master_dev) 7640 return master_dev == upper_dev ? -EEXIST : -EBUSY; 7641 } 7642 7643 ret = call_netdevice_notifiers_info(NETDEV_PRECHANGEUPPER, 7644 &changeupper_info.info); 7645 ret = notifier_to_errno(ret); 7646 if (ret) 7647 return ret; 7648 7649 ret = __netdev_adjacent_dev_link_neighbour(dev, upper_dev, upper_priv, 7650 master); 7651 if (ret) 7652 return ret; 7653 7654 ret = call_netdevice_notifiers_info(NETDEV_CHANGEUPPER, 7655 &changeupper_info.info); 7656 ret = notifier_to_errno(ret); 7657 if (ret) 7658 goto rollback; 7659 7660 __netdev_update_upper_level(dev, NULL); 7661 __netdev_walk_all_lower_dev(dev, __netdev_update_upper_level, NULL); 7662 7663 __netdev_update_lower_level(upper_dev, priv); 7664 __netdev_walk_all_upper_dev(upper_dev, __netdev_update_lower_level, 7665 priv); 7666 7667 return 0; 7668 7669 rollback: 7670 __netdev_adjacent_dev_unlink_neighbour(dev, upper_dev); 7671 7672 return ret; 7673 } 7674 7675 /** 7676 * netdev_upper_dev_link - Add a link to the upper device 7677 * @dev: device 7678 * @upper_dev: new upper device 7679 * @extack: netlink extended ack 7680 * 7681 * Adds a link to device which is upper to this one. The caller must hold 7682 * the RTNL lock. On a failure a negative errno code is returned. 7683 * On success the reference counts are adjusted and the function 7684 * returns zero. 7685 */ 7686 int netdev_upper_dev_link(struct net_device *dev, 7687 struct net_device *upper_dev, 7688 struct netlink_ext_ack *extack) 7689 { 7690 struct netdev_nested_priv priv = { 7691 .flags = NESTED_SYNC_IMM | NESTED_SYNC_TODO, 7692 .data = NULL, 7693 }; 7694 7695 return __netdev_upper_dev_link(dev, upper_dev, false, 7696 NULL, NULL, &priv, extack); 7697 } 7698 EXPORT_SYMBOL(netdev_upper_dev_link); 7699 7700 /** 7701 * netdev_master_upper_dev_link - Add a master link to the upper device 7702 * @dev: device 7703 * @upper_dev: new upper device 7704 * @upper_priv: upper device private 7705 * @upper_info: upper info to be passed down via notifier 7706 * @extack: netlink extended ack 7707 * 7708 * Adds a link to device which is upper to this one. In this case, only 7709 * one master upper device can be linked, although other non-master devices 7710 * might be linked as well. The caller must hold the RTNL lock. 7711 * On a failure a negative errno code is returned. On success the reference 7712 * counts are adjusted and the function returns zero. 7713 */ 7714 int netdev_master_upper_dev_link(struct net_device *dev, 7715 struct net_device *upper_dev, 7716 void *upper_priv, void *upper_info, 7717 struct netlink_ext_ack *extack) 7718 { 7719 struct netdev_nested_priv priv = { 7720 .flags = NESTED_SYNC_IMM | NESTED_SYNC_TODO, 7721 .data = NULL, 7722 }; 7723 7724 return __netdev_upper_dev_link(dev, upper_dev, true, 7725 upper_priv, upper_info, &priv, extack); 7726 } 7727 EXPORT_SYMBOL(netdev_master_upper_dev_link); 7728 7729 static void __netdev_upper_dev_unlink(struct net_device *dev, 7730 struct net_device *upper_dev, 7731 struct netdev_nested_priv *priv) 7732 { 7733 struct netdev_notifier_changeupper_info changeupper_info = { 7734 .info = { 7735 .dev = dev, 7736 }, 7737 .upper_dev = upper_dev, 7738 .linking = false, 7739 }; 7740 7741 ASSERT_RTNL(); 7742 7743 changeupper_info.master = netdev_master_upper_dev_get(dev) == upper_dev; 7744 7745 call_netdevice_notifiers_info(NETDEV_PRECHANGEUPPER, 7746 &changeupper_info.info); 7747 7748 __netdev_adjacent_dev_unlink_neighbour(dev, upper_dev); 7749 7750 call_netdevice_notifiers_info(NETDEV_CHANGEUPPER, 7751 &changeupper_info.info); 7752 7753 __netdev_update_upper_level(dev, NULL); 7754 __netdev_walk_all_lower_dev(dev, __netdev_update_upper_level, NULL); 7755 7756 __netdev_update_lower_level(upper_dev, priv); 7757 __netdev_walk_all_upper_dev(upper_dev, __netdev_update_lower_level, 7758 priv); 7759 } 7760 7761 /** 7762 * netdev_upper_dev_unlink - Removes a link to upper device 7763 * @dev: device 7764 * @upper_dev: new upper device 7765 * 7766 * Removes a link to device which is upper to this one. The caller must hold 7767 * the RTNL lock. 7768 */ 7769 void netdev_upper_dev_unlink(struct net_device *dev, 7770 struct net_device *upper_dev) 7771 { 7772 struct netdev_nested_priv priv = { 7773 .flags = NESTED_SYNC_TODO, 7774 .data = NULL, 7775 }; 7776 7777 __netdev_upper_dev_unlink(dev, upper_dev, &priv); 7778 } 7779 EXPORT_SYMBOL(netdev_upper_dev_unlink); 7780 7781 static void __netdev_adjacent_dev_set(struct net_device *upper_dev, 7782 struct net_device *lower_dev, 7783 bool val) 7784 { 7785 struct netdev_adjacent *adj; 7786 7787 adj = __netdev_find_adj(lower_dev, &upper_dev->adj_list.lower); 7788 if (adj) 7789 adj->ignore = val; 7790 7791 adj = __netdev_find_adj(upper_dev, &lower_dev->adj_list.upper); 7792 if (adj) 7793 adj->ignore = val; 7794 } 7795 7796 static void netdev_adjacent_dev_disable(struct net_device *upper_dev, 7797 struct net_device *lower_dev) 7798 { 7799 __netdev_adjacent_dev_set(upper_dev, lower_dev, true); 7800 } 7801 7802 static void netdev_adjacent_dev_enable(struct net_device *upper_dev, 7803 struct net_device *lower_dev) 7804 { 7805 __netdev_adjacent_dev_set(upper_dev, lower_dev, false); 7806 } 7807 7808 int netdev_adjacent_change_prepare(struct net_device *old_dev, 7809 struct net_device *new_dev, 7810 struct net_device *dev, 7811 struct netlink_ext_ack *extack) 7812 { 7813 struct netdev_nested_priv priv = { 7814 .flags = 0, 7815 .data = NULL, 7816 }; 7817 int err; 7818 7819 if (!new_dev) 7820 return 0; 7821 7822 if (old_dev && new_dev != old_dev) 7823 netdev_adjacent_dev_disable(dev, old_dev); 7824 err = __netdev_upper_dev_link(new_dev, dev, false, NULL, NULL, &priv, 7825 extack); 7826 if (err) { 7827 if (old_dev && new_dev != old_dev) 7828 netdev_adjacent_dev_enable(dev, old_dev); 7829 return err; 7830 } 7831 7832 return 0; 7833 } 7834 EXPORT_SYMBOL(netdev_adjacent_change_prepare); 7835 7836 void netdev_adjacent_change_commit(struct net_device *old_dev, 7837 struct net_device *new_dev, 7838 struct net_device *dev) 7839 { 7840 struct netdev_nested_priv priv = { 7841 .flags = NESTED_SYNC_IMM | NESTED_SYNC_TODO, 7842 .data = NULL, 7843 }; 7844 7845 if (!new_dev || !old_dev) 7846 return; 7847 7848 if (new_dev == old_dev) 7849 return; 7850 7851 netdev_adjacent_dev_enable(dev, old_dev); 7852 __netdev_upper_dev_unlink(old_dev, dev, &priv); 7853 } 7854 EXPORT_SYMBOL(netdev_adjacent_change_commit); 7855 7856 void netdev_adjacent_change_abort(struct net_device *old_dev, 7857 struct net_device *new_dev, 7858 struct net_device *dev) 7859 { 7860 struct netdev_nested_priv priv = { 7861 .flags = 0, 7862 .data = NULL, 7863 }; 7864 7865 if (!new_dev) 7866 return; 7867 7868 if (old_dev && new_dev != old_dev) 7869 netdev_adjacent_dev_enable(dev, old_dev); 7870 7871 __netdev_upper_dev_unlink(new_dev, dev, &priv); 7872 } 7873 EXPORT_SYMBOL(netdev_adjacent_change_abort); 7874 7875 /** 7876 * netdev_bonding_info_change - Dispatch event about slave change 7877 * @dev: device 7878 * @bonding_info: info to dispatch 7879 * 7880 * Send NETDEV_BONDING_INFO to netdev notifiers with info. 7881 * The caller must hold the RTNL lock. 7882 */ 7883 void netdev_bonding_info_change(struct net_device *dev, 7884 struct netdev_bonding_info *bonding_info) 7885 { 7886 struct netdev_notifier_bonding_info info = { 7887 .info.dev = dev, 7888 }; 7889 7890 memcpy(&info.bonding_info, bonding_info, 7891 sizeof(struct netdev_bonding_info)); 7892 call_netdevice_notifiers_info(NETDEV_BONDING_INFO, 7893 &info.info); 7894 } 7895 EXPORT_SYMBOL(netdev_bonding_info_change); 7896 7897 static int netdev_offload_xstats_enable_l3(struct net_device *dev, 7898 struct netlink_ext_ack *extack) 7899 { 7900 struct netdev_notifier_offload_xstats_info info = { 7901 .info.dev = dev, 7902 .info.extack = extack, 7903 .type = NETDEV_OFFLOAD_XSTATS_TYPE_L3, 7904 }; 7905 int err; 7906 int rc; 7907 7908 dev->offload_xstats_l3 = kzalloc(sizeof(*dev->offload_xstats_l3), 7909 GFP_KERNEL); 7910 if (!dev->offload_xstats_l3) 7911 return -ENOMEM; 7912 7913 rc = call_netdevice_notifiers_info_robust(NETDEV_OFFLOAD_XSTATS_ENABLE, 7914 NETDEV_OFFLOAD_XSTATS_DISABLE, 7915 &info.info); 7916 err = notifier_to_errno(rc); 7917 if (err) 7918 goto free_stats; 7919 7920 return 0; 7921 7922 free_stats: 7923 kfree(dev->offload_xstats_l3); 7924 dev->offload_xstats_l3 = NULL; 7925 return err; 7926 } 7927 7928 int netdev_offload_xstats_enable(struct net_device *dev, 7929 enum netdev_offload_xstats_type type, 7930 struct netlink_ext_ack *extack) 7931 { 7932 ASSERT_RTNL(); 7933 7934 if (netdev_offload_xstats_enabled(dev, type)) 7935 return -EALREADY; 7936 7937 switch (type) { 7938 case NETDEV_OFFLOAD_XSTATS_TYPE_L3: 7939 return netdev_offload_xstats_enable_l3(dev, extack); 7940 } 7941 7942 WARN_ON(1); 7943 return -EINVAL; 7944 } 7945 EXPORT_SYMBOL(netdev_offload_xstats_enable); 7946 7947 static void netdev_offload_xstats_disable_l3(struct net_device *dev) 7948 { 7949 struct netdev_notifier_offload_xstats_info info = { 7950 .info.dev = dev, 7951 .type = NETDEV_OFFLOAD_XSTATS_TYPE_L3, 7952 }; 7953 7954 call_netdevice_notifiers_info(NETDEV_OFFLOAD_XSTATS_DISABLE, 7955 &info.info); 7956 kfree(dev->offload_xstats_l3); 7957 dev->offload_xstats_l3 = NULL; 7958 } 7959 7960 int netdev_offload_xstats_disable(struct net_device *dev, 7961 enum netdev_offload_xstats_type type) 7962 { 7963 ASSERT_RTNL(); 7964 7965 if (!netdev_offload_xstats_enabled(dev, type)) 7966 return -EALREADY; 7967 7968 switch (type) { 7969 case NETDEV_OFFLOAD_XSTATS_TYPE_L3: 7970 netdev_offload_xstats_disable_l3(dev); 7971 return 0; 7972 } 7973 7974 WARN_ON(1); 7975 return -EINVAL; 7976 } 7977 EXPORT_SYMBOL(netdev_offload_xstats_disable); 7978 7979 static void netdev_offload_xstats_disable_all(struct net_device *dev) 7980 { 7981 netdev_offload_xstats_disable(dev, NETDEV_OFFLOAD_XSTATS_TYPE_L3); 7982 } 7983 7984 static struct rtnl_hw_stats64 * 7985 netdev_offload_xstats_get_ptr(const struct net_device *dev, 7986 enum netdev_offload_xstats_type type) 7987 { 7988 switch (type) { 7989 case NETDEV_OFFLOAD_XSTATS_TYPE_L3: 7990 return dev->offload_xstats_l3; 7991 } 7992 7993 WARN_ON(1); 7994 return NULL; 7995 } 7996 7997 bool netdev_offload_xstats_enabled(const struct net_device *dev, 7998 enum netdev_offload_xstats_type type) 7999 { 8000 ASSERT_RTNL(); 8001 8002 return netdev_offload_xstats_get_ptr(dev, type); 8003 } 8004 EXPORT_SYMBOL(netdev_offload_xstats_enabled); 8005 8006 struct netdev_notifier_offload_xstats_ru { 8007 bool used; 8008 }; 8009 8010 struct netdev_notifier_offload_xstats_rd { 8011 struct rtnl_hw_stats64 stats; 8012 bool used; 8013 }; 8014 8015 static void netdev_hw_stats64_add(struct rtnl_hw_stats64 *dest, 8016 const struct rtnl_hw_stats64 *src) 8017 { 8018 dest->rx_packets += src->rx_packets; 8019 dest->tx_packets += src->tx_packets; 8020 dest->rx_bytes += src->rx_bytes; 8021 dest->tx_bytes += src->tx_bytes; 8022 dest->rx_errors += src->rx_errors; 8023 dest->tx_errors += src->tx_errors; 8024 dest->rx_dropped += src->rx_dropped; 8025 dest->tx_dropped += src->tx_dropped; 8026 dest->multicast += src->multicast; 8027 } 8028 8029 static int netdev_offload_xstats_get_used(struct net_device *dev, 8030 enum netdev_offload_xstats_type type, 8031 bool *p_used, 8032 struct netlink_ext_ack *extack) 8033 { 8034 struct netdev_notifier_offload_xstats_ru report_used = {}; 8035 struct netdev_notifier_offload_xstats_info info = { 8036 .info.dev = dev, 8037 .info.extack = extack, 8038 .type = type, 8039 .report_used = &report_used, 8040 }; 8041 int rc; 8042 8043 WARN_ON(!netdev_offload_xstats_enabled(dev, type)); 8044 rc = call_netdevice_notifiers_info(NETDEV_OFFLOAD_XSTATS_REPORT_USED, 8045 &info.info); 8046 *p_used = report_used.used; 8047 return notifier_to_errno(rc); 8048 } 8049 8050 static int netdev_offload_xstats_get_stats(struct net_device *dev, 8051 enum netdev_offload_xstats_type type, 8052 struct rtnl_hw_stats64 *p_stats, 8053 bool *p_used, 8054 struct netlink_ext_ack *extack) 8055 { 8056 struct netdev_notifier_offload_xstats_rd report_delta = {}; 8057 struct netdev_notifier_offload_xstats_info info = { 8058 .info.dev = dev, 8059 .info.extack = extack, 8060 .type = type, 8061 .report_delta = &report_delta, 8062 }; 8063 struct rtnl_hw_stats64 *stats; 8064 int rc; 8065 8066 stats = netdev_offload_xstats_get_ptr(dev, type); 8067 if (WARN_ON(!stats)) 8068 return -EINVAL; 8069 8070 rc = call_netdevice_notifiers_info(NETDEV_OFFLOAD_XSTATS_REPORT_DELTA, 8071 &info.info); 8072 8073 /* Cache whatever we got, even if there was an error, otherwise the 8074 * successful stats retrievals would get lost. 8075 */ 8076 netdev_hw_stats64_add(stats, &report_delta.stats); 8077 8078 if (p_stats) 8079 *p_stats = *stats; 8080 *p_used = report_delta.used; 8081 8082 return notifier_to_errno(rc); 8083 } 8084 8085 int netdev_offload_xstats_get(struct net_device *dev, 8086 enum netdev_offload_xstats_type type, 8087 struct rtnl_hw_stats64 *p_stats, bool *p_used, 8088 struct netlink_ext_ack *extack) 8089 { 8090 ASSERT_RTNL(); 8091 8092 if (p_stats) 8093 return netdev_offload_xstats_get_stats(dev, type, p_stats, 8094 p_used, extack); 8095 else 8096 return netdev_offload_xstats_get_used(dev, type, p_used, 8097 extack); 8098 } 8099 EXPORT_SYMBOL(netdev_offload_xstats_get); 8100 8101 void 8102 netdev_offload_xstats_report_delta(struct netdev_notifier_offload_xstats_rd *report_delta, 8103 const struct rtnl_hw_stats64 *stats) 8104 { 8105 report_delta->used = true; 8106 netdev_hw_stats64_add(&report_delta->stats, stats); 8107 } 8108 EXPORT_SYMBOL(netdev_offload_xstats_report_delta); 8109 8110 void 8111 netdev_offload_xstats_report_used(struct netdev_notifier_offload_xstats_ru *report_used) 8112 { 8113 report_used->used = true; 8114 } 8115 EXPORT_SYMBOL(netdev_offload_xstats_report_used); 8116 8117 void netdev_offload_xstats_push_delta(struct net_device *dev, 8118 enum netdev_offload_xstats_type type, 8119 const struct rtnl_hw_stats64 *p_stats) 8120 { 8121 struct rtnl_hw_stats64 *stats; 8122 8123 ASSERT_RTNL(); 8124 8125 stats = netdev_offload_xstats_get_ptr(dev, type); 8126 if (WARN_ON(!stats)) 8127 return; 8128 8129 netdev_hw_stats64_add(stats, p_stats); 8130 } 8131 EXPORT_SYMBOL(netdev_offload_xstats_push_delta); 8132 8133 /** 8134 * netdev_get_xmit_slave - Get the xmit slave of master device 8135 * @dev: device 8136 * @skb: The packet 8137 * @all_slaves: assume all the slaves are active 8138 * 8139 * The reference counters are not incremented so the caller must be 8140 * careful with locks. The caller must hold RCU lock. 8141 * %NULL is returned if no slave is found. 8142 */ 8143 8144 struct net_device *netdev_get_xmit_slave(struct net_device *dev, 8145 struct sk_buff *skb, 8146 bool all_slaves) 8147 { 8148 const struct net_device_ops *ops = dev->netdev_ops; 8149 8150 if (!ops->ndo_get_xmit_slave) 8151 return NULL; 8152 return ops->ndo_get_xmit_slave(dev, skb, all_slaves); 8153 } 8154 EXPORT_SYMBOL(netdev_get_xmit_slave); 8155 8156 static struct net_device *netdev_sk_get_lower_dev(struct net_device *dev, 8157 struct sock *sk) 8158 { 8159 const struct net_device_ops *ops = dev->netdev_ops; 8160 8161 if (!ops->ndo_sk_get_lower_dev) 8162 return NULL; 8163 return ops->ndo_sk_get_lower_dev(dev, sk); 8164 } 8165 8166 /** 8167 * netdev_sk_get_lowest_dev - Get the lowest device in chain given device and socket 8168 * @dev: device 8169 * @sk: the socket 8170 * 8171 * %NULL is returned if no lower device is found. 8172 */ 8173 8174 struct net_device *netdev_sk_get_lowest_dev(struct net_device *dev, 8175 struct sock *sk) 8176 { 8177 struct net_device *lower; 8178 8179 lower = netdev_sk_get_lower_dev(dev, sk); 8180 while (lower) { 8181 dev = lower; 8182 lower = netdev_sk_get_lower_dev(dev, sk); 8183 } 8184 8185 return dev; 8186 } 8187 EXPORT_SYMBOL(netdev_sk_get_lowest_dev); 8188 8189 static void netdev_adjacent_add_links(struct net_device *dev) 8190 { 8191 struct netdev_adjacent *iter; 8192 8193 struct net *net = dev_net(dev); 8194 8195 list_for_each_entry(iter, &dev->adj_list.upper, list) { 8196 if (!net_eq(net, dev_net(iter->dev))) 8197 continue; 8198 netdev_adjacent_sysfs_add(iter->dev, dev, 8199 &iter->dev->adj_list.lower); 8200 netdev_adjacent_sysfs_add(dev, iter->dev, 8201 &dev->adj_list.upper); 8202 } 8203 8204 list_for_each_entry(iter, &dev->adj_list.lower, list) { 8205 if (!net_eq(net, dev_net(iter->dev))) 8206 continue; 8207 netdev_adjacent_sysfs_add(iter->dev, dev, 8208 &iter->dev->adj_list.upper); 8209 netdev_adjacent_sysfs_add(dev, iter->dev, 8210 &dev->adj_list.lower); 8211 } 8212 } 8213 8214 static void netdev_adjacent_del_links(struct net_device *dev) 8215 { 8216 struct netdev_adjacent *iter; 8217 8218 struct net *net = dev_net(dev); 8219 8220 list_for_each_entry(iter, &dev->adj_list.upper, list) { 8221 if (!net_eq(net, dev_net(iter->dev))) 8222 continue; 8223 netdev_adjacent_sysfs_del(iter->dev, dev->name, 8224 &iter->dev->adj_list.lower); 8225 netdev_adjacent_sysfs_del(dev, iter->dev->name, 8226 &dev->adj_list.upper); 8227 } 8228 8229 list_for_each_entry(iter, &dev->adj_list.lower, list) { 8230 if (!net_eq(net, dev_net(iter->dev))) 8231 continue; 8232 netdev_adjacent_sysfs_del(iter->dev, dev->name, 8233 &iter->dev->adj_list.upper); 8234 netdev_adjacent_sysfs_del(dev, iter->dev->name, 8235 &dev->adj_list.lower); 8236 } 8237 } 8238 8239 void netdev_adjacent_rename_links(struct net_device *dev, char *oldname) 8240 { 8241 struct netdev_adjacent *iter; 8242 8243 struct net *net = dev_net(dev); 8244 8245 list_for_each_entry(iter, &dev->adj_list.upper, list) { 8246 if (!net_eq(net, dev_net(iter->dev))) 8247 continue; 8248 netdev_adjacent_sysfs_del(iter->dev, oldname, 8249 &iter->dev->adj_list.lower); 8250 netdev_adjacent_sysfs_add(iter->dev, dev, 8251 &iter->dev->adj_list.lower); 8252 } 8253 8254 list_for_each_entry(iter, &dev->adj_list.lower, list) { 8255 if (!net_eq(net, dev_net(iter->dev))) 8256 continue; 8257 netdev_adjacent_sysfs_del(iter->dev, oldname, 8258 &iter->dev->adj_list.upper); 8259 netdev_adjacent_sysfs_add(iter->dev, dev, 8260 &iter->dev->adj_list.upper); 8261 } 8262 } 8263 8264 void *netdev_lower_dev_get_private(struct net_device *dev, 8265 struct net_device *lower_dev) 8266 { 8267 struct netdev_adjacent *lower; 8268 8269 if (!lower_dev) 8270 return NULL; 8271 lower = __netdev_find_adj(lower_dev, &dev->adj_list.lower); 8272 if (!lower) 8273 return NULL; 8274 8275 return lower->private; 8276 } 8277 EXPORT_SYMBOL(netdev_lower_dev_get_private); 8278 8279 8280 /** 8281 * netdev_lower_state_changed - Dispatch event about lower device state change 8282 * @lower_dev: device 8283 * @lower_state_info: state to dispatch 8284 * 8285 * Send NETDEV_CHANGELOWERSTATE to netdev notifiers with info. 8286 * The caller must hold the RTNL lock. 8287 */ 8288 void netdev_lower_state_changed(struct net_device *lower_dev, 8289 void *lower_state_info) 8290 { 8291 struct netdev_notifier_changelowerstate_info changelowerstate_info = { 8292 .info.dev = lower_dev, 8293 }; 8294 8295 ASSERT_RTNL(); 8296 changelowerstate_info.lower_state_info = lower_state_info; 8297 call_netdevice_notifiers_info(NETDEV_CHANGELOWERSTATE, 8298 &changelowerstate_info.info); 8299 } 8300 EXPORT_SYMBOL(netdev_lower_state_changed); 8301 8302 static void dev_change_rx_flags(struct net_device *dev, int flags) 8303 { 8304 const struct net_device_ops *ops = dev->netdev_ops; 8305 8306 if (ops->ndo_change_rx_flags) 8307 ops->ndo_change_rx_flags(dev, flags); 8308 } 8309 8310 static int __dev_set_promiscuity(struct net_device *dev, int inc, bool notify) 8311 { 8312 unsigned int old_flags = dev->flags; 8313 kuid_t uid; 8314 kgid_t gid; 8315 8316 ASSERT_RTNL(); 8317 8318 dev->flags |= IFF_PROMISC; 8319 dev->promiscuity += inc; 8320 if (dev->promiscuity == 0) { 8321 /* 8322 * Avoid overflow. 8323 * If inc causes overflow, untouch promisc and return error. 8324 */ 8325 if (inc < 0) 8326 dev->flags &= ~IFF_PROMISC; 8327 else { 8328 dev->promiscuity -= inc; 8329 netdev_warn(dev, "promiscuity touches roof, set promiscuity failed. promiscuity feature of device might be broken.\n"); 8330 return -EOVERFLOW; 8331 } 8332 } 8333 if (dev->flags != old_flags) { 8334 pr_info("device %s %s promiscuous mode\n", 8335 dev->name, 8336 dev->flags & IFF_PROMISC ? "entered" : "left"); 8337 if (audit_enabled) { 8338 current_uid_gid(&uid, &gid); 8339 audit_log(audit_context(), GFP_ATOMIC, 8340 AUDIT_ANOM_PROMISCUOUS, 8341 "dev=%s prom=%d old_prom=%d auid=%u uid=%u gid=%u ses=%u", 8342 dev->name, (dev->flags & IFF_PROMISC), 8343 (old_flags & IFF_PROMISC), 8344 from_kuid(&init_user_ns, audit_get_loginuid(current)), 8345 from_kuid(&init_user_ns, uid), 8346 from_kgid(&init_user_ns, gid), 8347 audit_get_sessionid(current)); 8348 } 8349 8350 dev_change_rx_flags(dev, IFF_PROMISC); 8351 } 8352 if (notify) 8353 __dev_notify_flags(dev, old_flags, IFF_PROMISC, 0, NULL); 8354 return 0; 8355 } 8356 8357 /** 8358 * dev_set_promiscuity - update promiscuity count on a device 8359 * @dev: device 8360 * @inc: modifier 8361 * 8362 * Add or remove promiscuity from a device. While the count in the device 8363 * remains above zero the interface remains promiscuous. Once it hits zero 8364 * the device reverts back to normal filtering operation. A negative inc 8365 * value is used to drop promiscuity on the device. 8366 * Return 0 if successful or a negative errno code on error. 8367 */ 8368 int dev_set_promiscuity(struct net_device *dev, int inc) 8369 { 8370 unsigned int old_flags = dev->flags; 8371 int err; 8372 8373 err = __dev_set_promiscuity(dev, inc, true); 8374 if (err < 0) 8375 return err; 8376 if (dev->flags != old_flags) 8377 dev_set_rx_mode(dev); 8378 return err; 8379 } 8380 EXPORT_SYMBOL(dev_set_promiscuity); 8381 8382 static int __dev_set_allmulti(struct net_device *dev, int inc, bool notify) 8383 { 8384 unsigned int old_flags = dev->flags, old_gflags = dev->gflags; 8385 8386 ASSERT_RTNL(); 8387 8388 dev->flags |= IFF_ALLMULTI; 8389 dev->allmulti += inc; 8390 if (dev->allmulti == 0) { 8391 /* 8392 * Avoid overflow. 8393 * If inc causes overflow, untouch allmulti and return error. 8394 */ 8395 if (inc < 0) 8396 dev->flags &= ~IFF_ALLMULTI; 8397 else { 8398 dev->allmulti -= inc; 8399 netdev_warn(dev, "allmulti touches roof, set allmulti failed. allmulti feature of device might be broken.\n"); 8400 return -EOVERFLOW; 8401 } 8402 } 8403 if (dev->flags ^ old_flags) { 8404 dev_change_rx_flags(dev, IFF_ALLMULTI); 8405 dev_set_rx_mode(dev); 8406 if (notify) 8407 __dev_notify_flags(dev, old_flags, 8408 dev->gflags ^ old_gflags, 0, NULL); 8409 } 8410 return 0; 8411 } 8412 8413 /** 8414 * dev_set_allmulti - update allmulti count on a device 8415 * @dev: device 8416 * @inc: modifier 8417 * 8418 * Add or remove reception of all multicast frames to a device. While the 8419 * count in the device remains above zero the interface remains listening 8420 * to all interfaces. Once it hits zero the device reverts back to normal 8421 * filtering operation. A negative @inc value is used to drop the counter 8422 * when releasing a resource needing all multicasts. 8423 * Return 0 if successful or a negative errno code on error. 8424 */ 8425 8426 int dev_set_allmulti(struct net_device *dev, int inc) 8427 { 8428 return __dev_set_allmulti(dev, inc, true); 8429 } 8430 EXPORT_SYMBOL(dev_set_allmulti); 8431 8432 /* 8433 * Upload unicast and multicast address lists to device and 8434 * configure RX filtering. When the device doesn't support unicast 8435 * filtering it is put in promiscuous mode while unicast addresses 8436 * are present. 8437 */ 8438 void __dev_set_rx_mode(struct net_device *dev) 8439 { 8440 const struct net_device_ops *ops = dev->netdev_ops; 8441 8442 /* dev_open will call this function so the list will stay sane. */ 8443 if (!(dev->flags&IFF_UP)) 8444 return; 8445 8446 if (!netif_device_present(dev)) 8447 return; 8448 8449 if (!(dev->priv_flags & IFF_UNICAST_FLT)) { 8450 /* Unicast addresses changes may only happen under the rtnl, 8451 * therefore calling __dev_set_promiscuity here is safe. 8452 */ 8453 if (!netdev_uc_empty(dev) && !dev->uc_promisc) { 8454 __dev_set_promiscuity(dev, 1, false); 8455 dev->uc_promisc = true; 8456 } else if (netdev_uc_empty(dev) && dev->uc_promisc) { 8457 __dev_set_promiscuity(dev, -1, false); 8458 dev->uc_promisc = false; 8459 } 8460 } 8461 8462 if (ops->ndo_set_rx_mode) 8463 ops->ndo_set_rx_mode(dev); 8464 } 8465 8466 void dev_set_rx_mode(struct net_device *dev) 8467 { 8468 netif_addr_lock_bh(dev); 8469 __dev_set_rx_mode(dev); 8470 netif_addr_unlock_bh(dev); 8471 } 8472 8473 /** 8474 * dev_get_flags - get flags reported to userspace 8475 * @dev: device 8476 * 8477 * Get the combination of flag bits exported through APIs to userspace. 8478 */ 8479 unsigned int dev_get_flags(const struct net_device *dev) 8480 { 8481 unsigned int flags; 8482 8483 flags = (dev->flags & ~(IFF_PROMISC | 8484 IFF_ALLMULTI | 8485 IFF_RUNNING | 8486 IFF_LOWER_UP | 8487 IFF_DORMANT)) | 8488 (dev->gflags & (IFF_PROMISC | 8489 IFF_ALLMULTI)); 8490 8491 if (netif_running(dev)) { 8492 if (netif_oper_up(dev)) 8493 flags |= IFF_RUNNING; 8494 if (netif_carrier_ok(dev)) 8495 flags |= IFF_LOWER_UP; 8496 if (netif_dormant(dev)) 8497 flags |= IFF_DORMANT; 8498 } 8499 8500 return flags; 8501 } 8502 EXPORT_SYMBOL(dev_get_flags); 8503 8504 int __dev_change_flags(struct net_device *dev, unsigned int flags, 8505 struct netlink_ext_ack *extack) 8506 { 8507 unsigned int old_flags = dev->flags; 8508 int ret; 8509 8510 ASSERT_RTNL(); 8511 8512 /* 8513 * Set the flags on our device. 8514 */ 8515 8516 dev->flags = (flags & (IFF_DEBUG | IFF_NOTRAILERS | IFF_NOARP | 8517 IFF_DYNAMIC | IFF_MULTICAST | IFF_PORTSEL | 8518 IFF_AUTOMEDIA)) | 8519 (dev->flags & (IFF_UP | IFF_VOLATILE | IFF_PROMISC | 8520 IFF_ALLMULTI)); 8521 8522 /* 8523 * Load in the correct multicast list now the flags have changed. 8524 */ 8525 8526 if ((old_flags ^ flags) & IFF_MULTICAST) 8527 dev_change_rx_flags(dev, IFF_MULTICAST); 8528 8529 dev_set_rx_mode(dev); 8530 8531 /* 8532 * Have we downed the interface. We handle IFF_UP ourselves 8533 * according to user attempts to set it, rather than blindly 8534 * setting it. 8535 */ 8536 8537 ret = 0; 8538 if ((old_flags ^ flags) & IFF_UP) { 8539 if (old_flags & IFF_UP) 8540 __dev_close(dev); 8541 else 8542 ret = __dev_open(dev, extack); 8543 } 8544 8545 if ((flags ^ dev->gflags) & IFF_PROMISC) { 8546 int inc = (flags & IFF_PROMISC) ? 1 : -1; 8547 unsigned int old_flags = dev->flags; 8548 8549 dev->gflags ^= IFF_PROMISC; 8550 8551 if (__dev_set_promiscuity(dev, inc, false) >= 0) 8552 if (dev->flags != old_flags) 8553 dev_set_rx_mode(dev); 8554 } 8555 8556 /* NOTE: order of synchronization of IFF_PROMISC and IFF_ALLMULTI 8557 * is important. Some (broken) drivers set IFF_PROMISC, when 8558 * IFF_ALLMULTI is requested not asking us and not reporting. 8559 */ 8560 if ((flags ^ dev->gflags) & IFF_ALLMULTI) { 8561 int inc = (flags & IFF_ALLMULTI) ? 1 : -1; 8562 8563 dev->gflags ^= IFF_ALLMULTI; 8564 __dev_set_allmulti(dev, inc, false); 8565 } 8566 8567 return ret; 8568 } 8569 8570 void __dev_notify_flags(struct net_device *dev, unsigned int old_flags, 8571 unsigned int gchanges, u32 portid, 8572 const struct nlmsghdr *nlh) 8573 { 8574 unsigned int changes = dev->flags ^ old_flags; 8575 8576 if (gchanges) 8577 rtmsg_ifinfo(RTM_NEWLINK, dev, gchanges, GFP_ATOMIC, portid, nlh); 8578 8579 if (changes & IFF_UP) { 8580 if (dev->flags & IFF_UP) 8581 call_netdevice_notifiers(NETDEV_UP, dev); 8582 else 8583 call_netdevice_notifiers(NETDEV_DOWN, dev); 8584 } 8585 8586 if (dev->flags & IFF_UP && 8587 (changes & ~(IFF_UP | IFF_PROMISC | IFF_ALLMULTI | IFF_VOLATILE))) { 8588 struct netdev_notifier_change_info change_info = { 8589 .info = { 8590 .dev = dev, 8591 }, 8592 .flags_changed = changes, 8593 }; 8594 8595 call_netdevice_notifiers_info(NETDEV_CHANGE, &change_info.info); 8596 } 8597 } 8598 8599 /** 8600 * dev_change_flags - change device settings 8601 * @dev: device 8602 * @flags: device state flags 8603 * @extack: netlink extended ack 8604 * 8605 * Change settings on device based state flags. The flags are 8606 * in the userspace exported format. 8607 */ 8608 int dev_change_flags(struct net_device *dev, unsigned int flags, 8609 struct netlink_ext_ack *extack) 8610 { 8611 int ret; 8612 unsigned int changes, old_flags = dev->flags, old_gflags = dev->gflags; 8613 8614 ret = __dev_change_flags(dev, flags, extack); 8615 if (ret < 0) 8616 return ret; 8617 8618 changes = (old_flags ^ dev->flags) | (old_gflags ^ dev->gflags); 8619 __dev_notify_flags(dev, old_flags, changes, 0, NULL); 8620 return ret; 8621 } 8622 EXPORT_SYMBOL(dev_change_flags); 8623 8624 int __dev_set_mtu(struct net_device *dev, int new_mtu) 8625 { 8626 const struct net_device_ops *ops = dev->netdev_ops; 8627 8628 if (ops->ndo_change_mtu) 8629 return ops->ndo_change_mtu(dev, new_mtu); 8630 8631 /* Pairs with all the lockless reads of dev->mtu in the stack */ 8632 WRITE_ONCE(dev->mtu, new_mtu); 8633 return 0; 8634 } 8635 EXPORT_SYMBOL(__dev_set_mtu); 8636 8637 int dev_validate_mtu(struct net_device *dev, int new_mtu, 8638 struct netlink_ext_ack *extack) 8639 { 8640 /* MTU must be positive, and in range */ 8641 if (new_mtu < 0 || new_mtu < dev->min_mtu) { 8642 NL_SET_ERR_MSG(extack, "mtu less than device minimum"); 8643 return -EINVAL; 8644 } 8645 8646 if (dev->max_mtu > 0 && new_mtu > dev->max_mtu) { 8647 NL_SET_ERR_MSG(extack, "mtu greater than device maximum"); 8648 return -EINVAL; 8649 } 8650 return 0; 8651 } 8652 8653 /** 8654 * dev_set_mtu_ext - Change maximum transfer unit 8655 * @dev: device 8656 * @new_mtu: new transfer unit 8657 * @extack: netlink extended ack 8658 * 8659 * Change the maximum transfer size of the network device. 8660 */ 8661 int dev_set_mtu_ext(struct net_device *dev, int new_mtu, 8662 struct netlink_ext_ack *extack) 8663 { 8664 int err, orig_mtu; 8665 8666 if (new_mtu == dev->mtu) 8667 return 0; 8668 8669 err = dev_validate_mtu(dev, new_mtu, extack); 8670 if (err) 8671 return err; 8672 8673 if (!netif_device_present(dev)) 8674 return -ENODEV; 8675 8676 err = call_netdevice_notifiers(NETDEV_PRECHANGEMTU, dev); 8677 err = notifier_to_errno(err); 8678 if (err) 8679 return err; 8680 8681 orig_mtu = dev->mtu; 8682 err = __dev_set_mtu(dev, new_mtu); 8683 8684 if (!err) { 8685 err = call_netdevice_notifiers_mtu(NETDEV_CHANGEMTU, dev, 8686 orig_mtu); 8687 err = notifier_to_errno(err); 8688 if (err) { 8689 /* setting mtu back and notifying everyone again, 8690 * so that they have a chance to revert changes. 8691 */ 8692 __dev_set_mtu(dev, orig_mtu); 8693 call_netdevice_notifiers_mtu(NETDEV_CHANGEMTU, dev, 8694 new_mtu); 8695 } 8696 } 8697 return err; 8698 } 8699 8700 int dev_set_mtu(struct net_device *dev, int new_mtu) 8701 { 8702 struct netlink_ext_ack extack; 8703 int err; 8704 8705 memset(&extack, 0, sizeof(extack)); 8706 err = dev_set_mtu_ext(dev, new_mtu, &extack); 8707 if (err && extack._msg) 8708 net_err_ratelimited("%s: %s\n", dev->name, extack._msg); 8709 return err; 8710 } 8711 EXPORT_SYMBOL(dev_set_mtu); 8712 8713 /** 8714 * dev_change_tx_queue_len - Change TX queue length of a netdevice 8715 * @dev: device 8716 * @new_len: new tx queue length 8717 */ 8718 int dev_change_tx_queue_len(struct net_device *dev, unsigned long new_len) 8719 { 8720 unsigned int orig_len = dev->tx_queue_len; 8721 int res; 8722 8723 if (new_len != (unsigned int)new_len) 8724 return -ERANGE; 8725 8726 if (new_len != orig_len) { 8727 dev->tx_queue_len = new_len; 8728 res = call_netdevice_notifiers(NETDEV_CHANGE_TX_QUEUE_LEN, dev); 8729 res = notifier_to_errno(res); 8730 if (res) 8731 goto err_rollback; 8732 res = dev_qdisc_change_tx_queue_len(dev); 8733 if (res) 8734 goto err_rollback; 8735 } 8736 8737 return 0; 8738 8739 err_rollback: 8740 netdev_err(dev, "refused to change device tx_queue_len\n"); 8741 dev->tx_queue_len = orig_len; 8742 return res; 8743 } 8744 8745 /** 8746 * dev_set_group - Change group this device belongs to 8747 * @dev: device 8748 * @new_group: group this device should belong to 8749 */ 8750 void dev_set_group(struct net_device *dev, int new_group) 8751 { 8752 dev->group = new_group; 8753 } 8754 8755 /** 8756 * dev_pre_changeaddr_notify - Call NETDEV_PRE_CHANGEADDR. 8757 * @dev: device 8758 * @addr: new address 8759 * @extack: netlink extended ack 8760 */ 8761 int dev_pre_changeaddr_notify(struct net_device *dev, const char *addr, 8762 struct netlink_ext_ack *extack) 8763 { 8764 struct netdev_notifier_pre_changeaddr_info info = { 8765 .info.dev = dev, 8766 .info.extack = extack, 8767 .dev_addr = addr, 8768 }; 8769 int rc; 8770 8771 rc = call_netdevice_notifiers_info(NETDEV_PRE_CHANGEADDR, &info.info); 8772 return notifier_to_errno(rc); 8773 } 8774 EXPORT_SYMBOL(dev_pre_changeaddr_notify); 8775 8776 /** 8777 * dev_set_mac_address - Change Media Access Control Address 8778 * @dev: device 8779 * @sa: new address 8780 * @extack: netlink extended ack 8781 * 8782 * Change the hardware (MAC) address of the device 8783 */ 8784 int dev_set_mac_address(struct net_device *dev, struct sockaddr *sa, 8785 struct netlink_ext_ack *extack) 8786 { 8787 const struct net_device_ops *ops = dev->netdev_ops; 8788 int err; 8789 8790 if (!ops->ndo_set_mac_address) 8791 return -EOPNOTSUPP; 8792 if (sa->sa_family != dev->type) 8793 return -EINVAL; 8794 if (!netif_device_present(dev)) 8795 return -ENODEV; 8796 err = dev_pre_changeaddr_notify(dev, sa->sa_data, extack); 8797 if (err) 8798 return err; 8799 err = ops->ndo_set_mac_address(dev, sa); 8800 if (err) 8801 return err; 8802 dev->addr_assign_type = NET_ADDR_SET; 8803 call_netdevice_notifiers(NETDEV_CHANGEADDR, dev); 8804 add_device_randomness(dev->dev_addr, dev->addr_len); 8805 return 0; 8806 } 8807 EXPORT_SYMBOL(dev_set_mac_address); 8808 8809 static DECLARE_RWSEM(dev_addr_sem); 8810 8811 int dev_set_mac_address_user(struct net_device *dev, struct sockaddr *sa, 8812 struct netlink_ext_ack *extack) 8813 { 8814 int ret; 8815 8816 down_write(&dev_addr_sem); 8817 ret = dev_set_mac_address(dev, sa, extack); 8818 up_write(&dev_addr_sem); 8819 return ret; 8820 } 8821 EXPORT_SYMBOL(dev_set_mac_address_user); 8822 8823 int dev_get_mac_address(struct sockaddr *sa, struct net *net, char *dev_name) 8824 { 8825 size_t size = sizeof(sa->sa_data_min); 8826 struct net_device *dev; 8827 int ret = 0; 8828 8829 down_read(&dev_addr_sem); 8830 rcu_read_lock(); 8831 8832 dev = dev_get_by_name_rcu(net, dev_name); 8833 if (!dev) { 8834 ret = -ENODEV; 8835 goto unlock; 8836 } 8837 if (!dev->addr_len) 8838 memset(sa->sa_data, 0, size); 8839 else 8840 memcpy(sa->sa_data, dev->dev_addr, 8841 min_t(size_t, size, dev->addr_len)); 8842 sa->sa_family = dev->type; 8843 8844 unlock: 8845 rcu_read_unlock(); 8846 up_read(&dev_addr_sem); 8847 return ret; 8848 } 8849 EXPORT_SYMBOL(dev_get_mac_address); 8850 8851 /** 8852 * dev_change_carrier - Change device carrier 8853 * @dev: device 8854 * @new_carrier: new value 8855 * 8856 * Change device carrier 8857 */ 8858 int dev_change_carrier(struct net_device *dev, bool new_carrier) 8859 { 8860 const struct net_device_ops *ops = dev->netdev_ops; 8861 8862 if (!ops->ndo_change_carrier) 8863 return -EOPNOTSUPP; 8864 if (!netif_device_present(dev)) 8865 return -ENODEV; 8866 return ops->ndo_change_carrier(dev, new_carrier); 8867 } 8868 8869 /** 8870 * dev_get_phys_port_id - Get device physical port ID 8871 * @dev: device 8872 * @ppid: port ID 8873 * 8874 * Get device physical port ID 8875 */ 8876 int dev_get_phys_port_id(struct net_device *dev, 8877 struct netdev_phys_item_id *ppid) 8878 { 8879 const struct net_device_ops *ops = dev->netdev_ops; 8880 8881 if (!ops->ndo_get_phys_port_id) 8882 return -EOPNOTSUPP; 8883 return ops->ndo_get_phys_port_id(dev, ppid); 8884 } 8885 8886 /** 8887 * dev_get_phys_port_name - Get device physical port name 8888 * @dev: device 8889 * @name: port name 8890 * @len: limit of bytes to copy to name 8891 * 8892 * Get device physical port name 8893 */ 8894 int dev_get_phys_port_name(struct net_device *dev, 8895 char *name, size_t len) 8896 { 8897 const struct net_device_ops *ops = dev->netdev_ops; 8898 int err; 8899 8900 if (ops->ndo_get_phys_port_name) { 8901 err = ops->ndo_get_phys_port_name(dev, name, len); 8902 if (err != -EOPNOTSUPP) 8903 return err; 8904 } 8905 return devlink_compat_phys_port_name_get(dev, name, len); 8906 } 8907 8908 /** 8909 * dev_get_port_parent_id - Get the device's port parent identifier 8910 * @dev: network device 8911 * @ppid: pointer to a storage for the port's parent identifier 8912 * @recurse: allow/disallow recursion to lower devices 8913 * 8914 * Get the devices's port parent identifier 8915 */ 8916 int dev_get_port_parent_id(struct net_device *dev, 8917 struct netdev_phys_item_id *ppid, 8918 bool recurse) 8919 { 8920 const struct net_device_ops *ops = dev->netdev_ops; 8921 struct netdev_phys_item_id first = { }; 8922 struct net_device *lower_dev; 8923 struct list_head *iter; 8924 int err; 8925 8926 if (ops->ndo_get_port_parent_id) { 8927 err = ops->ndo_get_port_parent_id(dev, ppid); 8928 if (err != -EOPNOTSUPP) 8929 return err; 8930 } 8931 8932 err = devlink_compat_switch_id_get(dev, ppid); 8933 if (!recurse || err != -EOPNOTSUPP) 8934 return err; 8935 8936 netdev_for_each_lower_dev(dev, lower_dev, iter) { 8937 err = dev_get_port_parent_id(lower_dev, ppid, true); 8938 if (err) 8939 break; 8940 if (!first.id_len) 8941 first = *ppid; 8942 else if (memcmp(&first, ppid, sizeof(*ppid))) 8943 return -EOPNOTSUPP; 8944 } 8945 8946 return err; 8947 } 8948 EXPORT_SYMBOL(dev_get_port_parent_id); 8949 8950 /** 8951 * netdev_port_same_parent_id - Indicate if two network devices have 8952 * the same port parent identifier 8953 * @a: first network device 8954 * @b: second network device 8955 */ 8956 bool netdev_port_same_parent_id(struct net_device *a, struct net_device *b) 8957 { 8958 struct netdev_phys_item_id a_id = { }; 8959 struct netdev_phys_item_id b_id = { }; 8960 8961 if (dev_get_port_parent_id(a, &a_id, true) || 8962 dev_get_port_parent_id(b, &b_id, true)) 8963 return false; 8964 8965 return netdev_phys_item_id_same(&a_id, &b_id); 8966 } 8967 EXPORT_SYMBOL(netdev_port_same_parent_id); 8968 8969 /** 8970 * dev_change_proto_down - set carrier according to proto_down. 8971 * 8972 * @dev: device 8973 * @proto_down: new value 8974 */ 8975 int dev_change_proto_down(struct net_device *dev, bool proto_down) 8976 { 8977 if (!(dev->priv_flags & IFF_CHANGE_PROTO_DOWN)) 8978 return -EOPNOTSUPP; 8979 if (!netif_device_present(dev)) 8980 return -ENODEV; 8981 if (proto_down) 8982 netif_carrier_off(dev); 8983 else 8984 netif_carrier_on(dev); 8985 dev->proto_down = proto_down; 8986 return 0; 8987 } 8988 8989 /** 8990 * dev_change_proto_down_reason - proto down reason 8991 * 8992 * @dev: device 8993 * @mask: proto down mask 8994 * @value: proto down value 8995 */ 8996 void dev_change_proto_down_reason(struct net_device *dev, unsigned long mask, 8997 u32 value) 8998 { 8999 int b; 9000 9001 if (!mask) { 9002 dev->proto_down_reason = value; 9003 } else { 9004 for_each_set_bit(b, &mask, 32) { 9005 if (value & (1 << b)) 9006 dev->proto_down_reason |= BIT(b); 9007 else 9008 dev->proto_down_reason &= ~BIT(b); 9009 } 9010 } 9011 } 9012 9013 struct bpf_xdp_link { 9014 struct bpf_link link; 9015 struct net_device *dev; /* protected by rtnl_lock, no refcnt held */ 9016 int flags; 9017 }; 9018 9019 static enum bpf_xdp_mode dev_xdp_mode(struct net_device *dev, u32 flags) 9020 { 9021 if (flags & XDP_FLAGS_HW_MODE) 9022 return XDP_MODE_HW; 9023 if (flags & XDP_FLAGS_DRV_MODE) 9024 return XDP_MODE_DRV; 9025 if (flags & XDP_FLAGS_SKB_MODE) 9026 return XDP_MODE_SKB; 9027 return dev->netdev_ops->ndo_bpf ? XDP_MODE_DRV : XDP_MODE_SKB; 9028 } 9029 9030 static bpf_op_t dev_xdp_bpf_op(struct net_device *dev, enum bpf_xdp_mode mode) 9031 { 9032 switch (mode) { 9033 case XDP_MODE_SKB: 9034 return generic_xdp_install; 9035 case XDP_MODE_DRV: 9036 case XDP_MODE_HW: 9037 return dev->netdev_ops->ndo_bpf; 9038 default: 9039 return NULL; 9040 } 9041 } 9042 9043 static struct bpf_xdp_link *dev_xdp_link(struct net_device *dev, 9044 enum bpf_xdp_mode mode) 9045 { 9046 return dev->xdp_state[mode].link; 9047 } 9048 9049 static struct bpf_prog *dev_xdp_prog(struct net_device *dev, 9050 enum bpf_xdp_mode mode) 9051 { 9052 struct bpf_xdp_link *link = dev_xdp_link(dev, mode); 9053 9054 if (link) 9055 return link->link.prog; 9056 return dev->xdp_state[mode].prog; 9057 } 9058 9059 u8 dev_xdp_prog_count(struct net_device *dev) 9060 { 9061 u8 count = 0; 9062 int i; 9063 9064 for (i = 0; i < __MAX_XDP_MODE; i++) 9065 if (dev->xdp_state[i].prog || dev->xdp_state[i].link) 9066 count++; 9067 return count; 9068 } 9069 EXPORT_SYMBOL_GPL(dev_xdp_prog_count); 9070 9071 u32 dev_xdp_prog_id(struct net_device *dev, enum bpf_xdp_mode mode) 9072 { 9073 struct bpf_prog *prog = dev_xdp_prog(dev, mode); 9074 9075 return prog ? prog->aux->id : 0; 9076 } 9077 9078 static void dev_xdp_set_link(struct net_device *dev, enum bpf_xdp_mode mode, 9079 struct bpf_xdp_link *link) 9080 { 9081 dev->xdp_state[mode].link = link; 9082 dev->xdp_state[mode].prog = NULL; 9083 } 9084 9085 static void dev_xdp_set_prog(struct net_device *dev, enum bpf_xdp_mode mode, 9086 struct bpf_prog *prog) 9087 { 9088 dev->xdp_state[mode].link = NULL; 9089 dev->xdp_state[mode].prog = prog; 9090 } 9091 9092 static int dev_xdp_install(struct net_device *dev, enum bpf_xdp_mode mode, 9093 bpf_op_t bpf_op, struct netlink_ext_ack *extack, 9094 u32 flags, struct bpf_prog *prog) 9095 { 9096 struct netdev_bpf xdp; 9097 int err; 9098 9099 memset(&xdp, 0, sizeof(xdp)); 9100 xdp.command = mode == XDP_MODE_HW ? XDP_SETUP_PROG_HW : XDP_SETUP_PROG; 9101 xdp.extack = extack; 9102 xdp.flags = flags; 9103 xdp.prog = prog; 9104 9105 /* Drivers assume refcnt is already incremented (i.e, prog pointer is 9106 * "moved" into driver), so they don't increment it on their own, but 9107 * they do decrement refcnt when program is detached or replaced. 9108 * Given net_device also owns link/prog, we need to bump refcnt here 9109 * to prevent drivers from underflowing it. 9110 */ 9111 if (prog) 9112 bpf_prog_inc(prog); 9113 err = bpf_op(dev, &xdp); 9114 if (err) { 9115 if (prog) 9116 bpf_prog_put(prog); 9117 return err; 9118 } 9119 9120 if (mode != XDP_MODE_HW) 9121 bpf_prog_change_xdp(dev_xdp_prog(dev, mode), prog); 9122 9123 return 0; 9124 } 9125 9126 static void dev_xdp_uninstall(struct net_device *dev) 9127 { 9128 struct bpf_xdp_link *link; 9129 struct bpf_prog *prog; 9130 enum bpf_xdp_mode mode; 9131 bpf_op_t bpf_op; 9132 9133 ASSERT_RTNL(); 9134 9135 for (mode = XDP_MODE_SKB; mode < __MAX_XDP_MODE; mode++) { 9136 prog = dev_xdp_prog(dev, mode); 9137 if (!prog) 9138 continue; 9139 9140 bpf_op = dev_xdp_bpf_op(dev, mode); 9141 if (!bpf_op) 9142 continue; 9143 9144 WARN_ON(dev_xdp_install(dev, mode, bpf_op, NULL, 0, NULL)); 9145 9146 /* auto-detach link from net device */ 9147 link = dev_xdp_link(dev, mode); 9148 if (link) 9149 link->dev = NULL; 9150 else 9151 bpf_prog_put(prog); 9152 9153 dev_xdp_set_link(dev, mode, NULL); 9154 } 9155 } 9156 9157 static int dev_xdp_attach(struct net_device *dev, struct netlink_ext_ack *extack, 9158 struct bpf_xdp_link *link, struct bpf_prog *new_prog, 9159 struct bpf_prog *old_prog, u32 flags) 9160 { 9161 unsigned int num_modes = hweight32(flags & XDP_FLAGS_MODES); 9162 struct bpf_prog *cur_prog; 9163 struct net_device *upper; 9164 struct list_head *iter; 9165 enum bpf_xdp_mode mode; 9166 bpf_op_t bpf_op; 9167 int err; 9168 9169 ASSERT_RTNL(); 9170 9171 /* either link or prog attachment, never both */ 9172 if (link && (new_prog || old_prog)) 9173 return -EINVAL; 9174 /* link supports only XDP mode flags */ 9175 if (link && (flags & ~XDP_FLAGS_MODES)) { 9176 NL_SET_ERR_MSG(extack, "Invalid XDP flags for BPF link attachment"); 9177 return -EINVAL; 9178 } 9179 /* just one XDP mode bit should be set, zero defaults to drv/skb mode */ 9180 if (num_modes > 1) { 9181 NL_SET_ERR_MSG(extack, "Only one XDP mode flag can be set"); 9182 return -EINVAL; 9183 } 9184 /* avoid ambiguity if offload + drv/skb mode progs are both loaded */ 9185 if (!num_modes && dev_xdp_prog_count(dev) > 1) { 9186 NL_SET_ERR_MSG(extack, 9187 "More than one program loaded, unset mode is ambiguous"); 9188 return -EINVAL; 9189 } 9190 /* old_prog != NULL implies XDP_FLAGS_REPLACE is set */ 9191 if (old_prog && !(flags & XDP_FLAGS_REPLACE)) { 9192 NL_SET_ERR_MSG(extack, "XDP_FLAGS_REPLACE is not specified"); 9193 return -EINVAL; 9194 } 9195 9196 mode = dev_xdp_mode(dev, flags); 9197 /* can't replace attached link */ 9198 if (dev_xdp_link(dev, mode)) { 9199 NL_SET_ERR_MSG(extack, "Can't replace active BPF XDP link"); 9200 return -EBUSY; 9201 } 9202 9203 /* don't allow if an upper device already has a program */ 9204 netdev_for_each_upper_dev_rcu(dev, upper, iter) { 9205 if (dev_xdp_prog_count(upper) > 0) { 9206 NL_SET_ERR_MSG(extack, "Cannot attach when an upper device already has a program"); 9207 return -EEXIST; 9208 } 9209 } 9210 9211 cur_prog = dev_xdp_prog(dev, mode); 9212 /* can't replace attached prog with link */ 9213 if (link && cur_prog) { 9214 NL_SET_ERR_MSG(extack, "Can't replace active XDP program with BPF link"); 9215 return -EBUSY; 9216 } 9217 if ((flags & XDP_FLAGS_REPLACE) && cur_prog != old_prog) { 9218 NL_SET_ERR_MSG(extack, "Active program does not match expected"); 9219 return -EEXIST; 9220 } 9221 9222 /* put effective new program into new_prog */ 9223 if (link) 9224 new_prog = link->link.prog; 9225 9226 if (new_prog) { 9227 bool offload = mode == XDP_MODE_HW; 9228 enum bpf_xdp_mode other_mode = mode == XDP_MODE_SKB 9229 ? XDP_MODE_DRV : XDP_MODE_SKB; 9230 9231 if ((flags & XDP_FLAGS_UPDATE_IF_NOEXIST) && cur_prog) { 9232 NL_SET_ERR_MSG(extack, "XDP program already attached"); 9233 return -EBUSY; 9234 } 9235 if (!offload && dev_xdp_prog(dev, other_mode)) { 9236 NL_SET_ERR_MSG(extack, "Native and generic XDP can't be active at the same time"); 9237 return -EEXIST; 9238 } 9239 if (!offload && bpf_prog_is_dev_bound(new_prog->aux)) { 9240 NL_SET_ERR_MSG(extack, "Using device-bound program without HW_MODE flag is not supported"); 9241 return -EINVAL; 9242 } 9243 if (new_prog->expected_attach_type == BPF_XDP_DEVMAP) { 9244 NL_SET_ERR_MSG(extack, "BPF_XDP_DEVMAP programs can not be attached to a device"); 9245 return -EINVAL; 9246 } 9247 if (new_prog->expected_attach_type == BPF_XDP_CPUMAP) { 9248 NL_SET_ERR_MSG(extack, "BPF_XDP_CPUMAP programs can not be attached to a device"); 9249 return -EINVAL; 9250 } 9251 } 9252 9253 /* don't call drivers if the effective program didn't change */ 9254 if (new_prog != cur_prog) { 9255 bpf_op = dev_xdp_bpf_op(dev, mode); 9256 if (!bpf_op) { 9257 NL_SET_ERR_MSG(extack, "Underlying driver does not support XDP in native mode"); 9258 return -EOPNOTSUPP; 9259 } 9260 9261 err = dev_xdp_install(dev, mode, bpf_op, extack, flags, new_prog); 9262 if (err) 9263 return err; 9264 } 9265 9266 if (link) 9267 dev_xdp_set_link(dev, mode, link); 9268 else 9269 dev_xdp_set_prog(dev, mode, new_prog); 9270 if (cur_prog) 9271 bpf_prog_put(cur_prog); 9272 9273 return 0; 9274 } 9275 9276 static int dev_xdp_attach_link(struct net_device *dev, 9277 struct netlink_ext_ack *extack, 9278 struct bpf_xdp_link *link) 9279 { 9280 return dev_xdp_attach(dev, extack, link, NULL, NULL, link->flags); 9281 } 9282 9283 static int dev_xdp_detach_link(struct net_device *dev, 9284 struct netlink_ext_ack *extack, 9285 struct bpf_xdp_link *link) 9286 { 9287 enum bpf_xdp_mode mode; 9288 bpf_op_t bpf_op; 9289 9290 ASSERT_RTNL(); 9291 9292 mode = dev_xdp_mode(dev, link->flags); 9293 if (dev_xdp_link(dev, mode) != link) 9294 return -EINVAL; 9295 9296 bpf_op = dev_xdp_bpf_op(dev, mode); 9297 WARN_ON(dev_xdp_install(dev, mode, bpf_op, NULL, 0, NULL)); 9298 dev_xdp_set_link(dev, mode, NULL); 9299 return 0; 9300 } 9301 9302 static void bpf_xdp_link_release(struct bpf_link *link) 9303 { 9304 struct bpf_xdp_link *xdp_link = container_of(link, struct bpf_xdp_link, link); 9305 9306 rtnl_lock(); 9307 9308 /* if racing with net_device's tear down, xdp_link->dev might be 9309 * already NULL, in which case link was already auto-detached 9310 */ 9311 if (xdp_link->dev) { 9312 WARN_ON(dev_xdp_detach_link(xdp_link->dev, NULL, xdp_link)); 9313 xdp_link->dev = NULL; 9314 } 9315 9316 rtnl_unlock(); 9317 } 9318 9319 static int bpf_xdp_link_detach(struct bpf_link *link) 9320 { 9321 bpf_xdp_link_release(link); 9322 return 0; 9323 } 9324 9325 static void bpf_xdp_link_dealloc(struct bpf_link *link) 9326 { 9327 struct bpf_xdp_link *xdp_link = container_of(link, struct bpf_xdp_link, link); 9328 9329 kfree(xdp_link); 9330 } 9331 9332 static void bpf_xdp_link_show_fdinfo(const struct bpf_link *link, 9333 struct seq_file *seq) 9334 { 9335 struct bpf_xdp_link *xdp_link = container_of(link, struct bpf_xdp_link, link); 9336 u32 ifindex = 0; 9337 9338 rtnl_lock(); 9339 if (xdp_link->dev) 9340 ifindex = xdp_link->dev->ifindex; 9341 rtnl_unlock(); 9342 9343 seq_printf(seq, "ifindex:\t%u\n", ifindex); 9344 } 9345 9346 static int bpf_xdp_link_fill_link_info(const struct bpf_link *link, 9347 struct bpf_link_info *info) 9348 { 9349 struct bpf_xdp_link *xdp_link = container_of(link, struct bpf_xdp_link, link); 9350 u32 ifindex = 0; 9351 9352 rtnl_lock(); 9353 if (xdp_link->dev) 9354 ifindex = xdp_link->dev->ifindex; 9355 rtnl_unlock(); 9356 9357 info->xdp.ifindex = ifindex; 9358 return 0; 9359 } 9360 9361 static int bpf_xdp_link_update(struct bpf_link *link, struct bpf_prog *new_prog, 9362 struct bpf_prog *old_prog) 9363 { 9364 struct bpf_xdp_link *xdp_link = container_of(link, struct bpf_xdp_link, link); 9365 enum bpf_xdp_mode mode; 9366 bpf_op_t bpf_op; 9367 int err = 0; 9368 9369 rtnl_lock(); 9370 9371 /* link might have been auto-released already, so fail */ 9372 if (!xdp_link->dev) { 9373 err = -ENOLINK; 9374 goto out_unlock; 9375 } 9376 9377 if (old_prog && link->prog != old_prog) { 9378 err = -EPERM; 9379 goto out_unlock; 9380 } 9381 old_prog = link->prog; 9382 if (old_prog->type != new_prog->type || 9383 old_prog->expected_attach_type != new_prog->expected_attach_type) { 9384 err = -EINVAL; 9385 goto out_unlock; 9386 } 9387 9388 if (old_prog == new_prog) { 9389 /* no-op, don't disturb drivers */ 9390 bpf_prog_put(new_prog); 9391 goto out_unlock; 9392 } 9393 9394 mode = dev_xdp_mode(xdp_link->dev, xdp_link->flags); 9395 bpf_op = dev_xdp_bpf_op(xdp_link->dev, mode); 9396 err = dev_xdp_install(xdp_link->dev, mode, bpf_op, NULL, 9397 xdp_link->flags, new_prog); 9398 if (err) 9399 goto out_unlock; 9400 9401 old_prog = xchg(&link->prog, new_prog); 9402 bpf_prog_put(old_prog); 9403 9404 out_unlock: 9405 rtnl_unlock(); 9406 return err; 9407 } 9408 9409 static const struct bpf_link_ops bpf_xdp_link_lops = { 9410 .release = bpf_xdp_link_release, 9411 .dealloc = bpf_xdp_link_dealloc, 9412 .detach = bpf_xdp_link_detach, 9413 .show_fdinfo = bpf_xdp_link_show_fdinfo, 9414 .fill_link_info = bpf_xdp_link_fill_link_info, 9415 .update_prog = bpf_xdp_link_update, 9416 }; 9417 9418 int bpf_xdp_link_attach(const union bpf_attr *attr, struct bpf_prog *prog) 9419 { 9420 struct net *net = current->nsproxy->net_ns; 9421 struct bpf_link_primer link_primer; 9422 struct bpf_xdp_link *link; 9423 struct net_device *dev; 9424 int err, fd; 9425 9426 rtnl_lock(); 9427 dev = dev_get_by_index(net, attr->link_create.target_ifindex); 9428 if (!dev) { 9429 rtnl_unlock(); 9430 return -EINVAL; 9431 } 9432 9433 link = kzalloc(sizeof(*link), GFP_USER); 9434 if (!link) { 9435 err = -ENOMEM; 9436 goto unlock; 9437 } 9438 9439 bpf_link_init(&link->link, BPF_LINK_TYPE_XDP, &bpf_xdp_link_lops, prog); 9440 link->dev = dev; 9441 link->flags = attr->link_create.flags; 9442 9443 err = bpf_link_prime(&link->link, &link_primer); 9444 if (err) { 9445 kfree(link); 9446 goto unlock; 9447 } 9448 9449 err = dev_xdp_attach_link(dev, NULL, link); 9450 rtnl_unlock(); 9451 9452 if (err) { 9453 link->dev = NULL; 9454 bpf_link_cleanup(&link_primer); 9455 goto out_put_dev; 9456 } 9457 9458 fd = bpf_link_settle(&link_primer); 9459 /* link itself doesn't hold dev's refcnt to not complicate shutdown */ 9460 dev_put(dev); 9461 return fd; 9462 9463 unlock: 9464 rtnl_unlock(); 9465 9466 out_put_dev: 9467 dev_put(dev); 9468 return err; 9469 } 9470 9471 /** 9472 * dev_change_xdp_fd - set or clear a bpf program for a device rx path 9473 * @dev: device 9474 * @extack: netlink extended ack 9475 * @fd: new program fd or negative value to clear 9476 * @expected_fd: old program fd that userspace expects to replace or clear 9477 * @flags: xdp-related flags 9478 * 9479 * Set or clear a bpf program for a device 9480 */ 9481 int dev_change_xdp_fd(struct net_device *dev, struct netlink_ext_ack *extack, 9482 int fd, int expected_fd, u32 flags) 9483 { 9484 enum bpf_xdp_mode mode = dev_xdp_mode(dev, flags); 9485 struct bpf_prog *new_prog = NULL, *old_prog = NULL; 9486 int err; 9487 9488 ASSERT_RTNL(); 9489 9490 if (fd >= 0) { 9491 new_prog = bpf_prog_get_type_dev(fd, BPF_PROG_TYPE_XDP, 9492 mode != XDP_MODE_SKB); 9493 if (IS_ERR(new_prog)) 9494 return PTR_ERR(new_prog); 9495 } 9496 9497 if (expected_fd >= 0) { 9498 old_prog = bpf_prog_get_type_dev(expected_fd, BPF_PROG_TYPE_XDP, 9499 mode != XDP_MODE_SKB); 9500 if (IS_ERR(old_prog)) { 9501 err = PTR_ERR(old_prog); 9502 old_prog = NULL; 9503 goto err_out; 9504 } 9505 } 9506 9507 err = dev_xdp_attach(dev, extack, NULL, new_prog, old_prog, flags); 9508 9509 err_out: 9510 if (err && new_prog) 9511 bpf_prog_put(new_prog); 9512 if (old_prog) 9513 bpf_prog_put(old_prog); 9514 return err; 9515 } 9516 9517 /** 9518 * dev_new_index - allocate an ifindex 9519 * @net: the applicable net namespace 9520 * 9521 * Returns a suitable unique value for a new device interface 9522 * number. The caller must hold the rtnl semaphore or the 9523 * dev_base_lock to be sure it remains unique. 9524 */ 9525 static int dev_new_index(struct net *net) 9526 { 9527 int ifindex = net->ifindex; 9528 9529 for (;;) { 9530 if (++ifindex <= 0) 9531 ifindex = 1; 9532 if (!__dev_get_by_index(net, ifindex)) 9533 return net->ifindex = ifindex; 9534 } 9535 } 9536 9537 /* Delayed registration/unregisteration */ 9538 LIST_HEAD(net_todo_list); 9539 DECLARE_WAIT_QUEUE_HEAD(netdev_unregistering_wq); 9540 9541 static void net_set_todo(struct net_device *dev) 9542 { 9543 list_add_tail(&dev->todo_list, &net_todo_list); 9544 atomic_inc(&dev_net(dev)->dev_unreg_count); 9545 } 9546 9547 static netdev_features_t netdev_sync_upper_features(struct net_device *lower, 9548 struct net_device *upper, netdev_features_t features) 9549 { 9550 netdev_features_t upper_disables = NETIF_F_UPPER_DISABLES; 9551 netdev_features_t feature; 9552 int feature_bit; 9553 9554 for_each_netdev_feature(upper_disables, feature_bit) { 9555 feature = __NETIF_F_BIT(feature_bit); 9556 if (!(upper->wanted_features & feature) 9557 && (features & feature)) { 9558 netdev_dbg(lower, "Dropping feature %pNF, upper dev %s has it off.\n", 9559 &feature, upper->name); 9560 features &= ~feature; 9561 } 9562 } 9563 9564 return features; 9565 } 9566 9567 static void netdev_sync_lower_features(struct net_device *upper, 9568 struct net_device *lower, netdev_features_t features) 9569 { 9570 netdev_features_t upper_disables = NETIF_F_UPPER_DISABLES; 9571 netdev_features_t feature; 9572 int feature_bit; 9573 9574 for_each_netdev_feature(upper_disables, feature_bit) { 9575 feature = __NETIF_F_BIT(feature_bit); 9576 if (!(features & feature) && (lower->features & feature)) { 9577 netdev_dbg(upper, "Disabling feature %pNF on lower dev %s.\n", 9578 &feature, lower->name); 9579 lower->wanted_features &= ~feature; 9580 __netdev_update_features(lower); 9581 9582 if (unlikely(lower->features & feature)) 9583 netdev_WARN(upper, "failed to disable %pNF on %s!\n", 9584 &feature, lower->name); 9585 else 9586 netdev_features_change(lower); 9587 } 9588 } 9589 } 9590 9591 static netdev_features_t netdev_fix_features(struct net_device *dev, 9592 netdev_features_t features) 9593 { 9594 /* Fix illegal checksum combinations */ 9595 if ((features & NETIF_F_HW_CSUM) && 9596 (features & (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))) { 9597 netdev_warn(dev, "mixed HW and IP checksum settings.\n"); 9598 features &= ~(NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM); 9599 } 9600 9601 /* TSO requires that SG is present as well. */ 9602 if ((features & NETIF_F_ALL_TSO) && !(features & NETIF_F_SG)) { 9603 netdev_dbg(dev, "Dropping TSO features since no SG feature.\n"); 9604 features &= ~NETIF_F_ALL_TSO; 9605 } 9606 9607 if ((features & NETIF_F_TSO) && !(features & NETIF_F_HW_CSUM) && 9608 !(features & NETIF_F_IP_CSUM)) { 9609 netdev_dbg(dev, "Dropping TSO features since no CSUM feature.\n"); 9610 features &= ~NETIF_F_TSO; 9611 features &= ~NETIF_F_TSO_ECN; 9612 } 9613 9614 if ((features & NETIF_F_TSO6) && !(features & NETIF_F_HW_CSUM) && 9615 !(features & NETIF_F_IPV6_CSUM)) { 9616 netdev_dbg(dev, "Dropping TSO6 features since no CSUM feature.\n"); 9617 features &= ~NETIF_F_TSO6; 9618 } 9619 9620 /* TSO with IPv4 ID mangling requires IPv4 TSO be enabled */ 9621 if ((features & NETIF_F_TSO_MANGLEID) && !(features & NETIF_F_TSO)) 9622 features &= ~NETIF_F_TSO_MANGLEID; 9623 9624 /* TSO ECN requires that TSO is present as well. */ 9625 if ((features & NETIF_F_ALL_TSO) == NETIF_F_TSO_ECN) 9626 features &= ~NETIF_F_TSO_ECN; 9627 9628 /* Software GSO depends on SG. */ 9629 if ((features & NETIF_F_GSO) && !(features & NETIF_F_SG)) { 9630 netdev_dbg(dev, "Dropping NETIF_F_GSO since no SG feature.\n"); 9631 features &= ~NETIF_F_GSO; 9632 } 9633 9634 /* GSO partial features require GSO partial be set */ 9635 if ((features & dev->gso_partial_features) && 9636 !(features & NETIF_F_GSO_PARTIAL)) { 9637 netdev_dbg(dev, 9638 "Dropping partially supported GSO features since no GSO partial.\n"); 9639 features &= ~dev->gso_partial_features; 9640 } 9641 9642 if (!(features & NETIF_F_RXCSUM)) { 9643 /* NETIF_F_GRO_HW implies doing RXCSUM since every packet 9644 * successfully merged by hardware must also have the 9645 * checksum verified by hardware. If the user does not 9646 * want to enable RXCSUM, logically, we should disable GRO_HW. 9647 */ 9648 if (features & NETIF_F_GRO_HW) { 9649 netdev_dbg(dev, "Dropping NETIF_F_GRO_HW since no RXCSUM feature.\n"); 9650 features &= ~NETIF_F_GRO_HW; 9651 } 9652 } 9653 9654 /* LRO/HW-GRO features cannot be combined with RX-FCS */ 9655 if (features & NETIF_F_RXFCS) { 9656 if (features & NETIF_F_LRO) { 9657 netdev_dbg(dev, "Dropping LRO feature since RX-FCS is requested.\n"); 9658 features &= ~NETIF_F_LRO; 9659 } 9660 9661 if (features & NETIF_F_GRO_HW) { 9662 netdev_dbg(dev, "Dropping HW-GRO feature since RX-FCS is requested.\n"); 9663 features &= ~NETIF_F_GRO_HW; 9664 } 9665 } 9666 9667 if ((features & NETIF_F_GRO_HW) && (features & NETIF_F_LRO)) { 9668 netdev_dbg(dev, "Dropping LRO feature since HW-GRO is requested.\n"); 9669 features &= ~NETIF_F_LRO; 9670 } 9671 9672 if (features & NETIF_F_HW_TLS_TX) { 9673 bool ip_csum = (features & (NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM)) == 9674 (NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM); 9675 bool hw_csum = features & NETIF_F_HW_CSUM; 9676 9677 if (!ip_csum && !hw_csum) { 9678 netdev_dbg(dev, "Dropping TLS TX HW offload feature since no CSUM feature.\n"); 9679 features &= ~NETIF_F_HW_TLS_TX; 9680 } 9681 } 9682 9683 if ((features & NETIF_F_HW_TLS_RX) && !(features & NETIF_F_RXCSUM)) { 9684 netdev_dbg(dev, "Dropping TLS RX HW offload feature since no RXCSUM feature.\n"); 9685 features &= ~NETIF_F_HW_TLS_RX; 9686 } 9687 9688 return features; 9689 } 9690 9691 int __netdev_update_features(struct net_device *dev) 9692 { 9693 struct net_device *upper, *lower; 9694 netdev_features_t features; 9695 struct list_head *iter; 9696 int err = -1; 9697 9698 ASSERT_RTNL(); 9699 9700 features = netdev_get_wanted_features(dev); 9701 9702 if (dev->netdev_ops->ndo_fix_features) 9703 features = dev->netdev_ops->ndo_fix_features(dev, features); 9704 9705 /* driver might be less strict about feature dependencies */ 9706 features = netdev_fix_features(dev, features); 9707 9708 /* some features can't be enabled if they're off on an upper device */ 9709 netdev_for_each_upper_dev_rcu(dev, upper, iter) 9710 features = netdev_sync_upper_features(dev, upper, features); 9711 9712 if (dev->features == features) 9713 goto sync_lower; 9714 9715 netdev_dbg(dev, "Features changed: %pNF -> %pNF\n", 9716 &dev->features, &features); 9717 9718 if (dev->netdev_ops->ndo_set_features) 9719 err = dev->netdev_ops->ndo_set_features(dev, features); 9720 else 9721 err = 0; 9722 9723 if (unlikely(err < 0)) { 9724 netdev_err(dev, 9725 "set_features() failed (%d); wanted %pNF, left %pNF\n", 9726 err, &features, &dev->features); 9727 /* return non-0 since some features might have changed and 9728 * it's better to fire a spurious notification than miss it 9729 */ 9730 return -1; 9731 } 9732 9733 sync_lower: 9734 /* some features must be disabled on lower devices when disabled 9735 * on an upper device (think: bonding master or bridge) 9736 */ 9737 netdev_for_each_lower_dev(dev, lower, iter) 9738 netdev_sync_lower_features(dev, lower, features); 9739 9740 if (!err) { 9741 netdev_features_t diff = features ^ dev->features; 9742 9743 if (diff & NETIF_F_RX_UDP_TUNNEL_PORT) { 9744 /* udp_tunnel_{get,drop}_rx_info both need 9745 * NETIF_F_RX_UDP_TUNNEL_PORT enabled on the 9746 * device, or they won't do anything. 9747 * Thus we need to update dev->features 9748 * *before* calling udp_tunnel_get_rx_info, 9749 * but *after* calling udp_tunnel_drop_rx_info. 9750 */ 9751 if (features & NETIF_F_RX_UDP_TUNNEL_PORT) { 9752 dev->features = features; 9753 udp_tunnel_get_rx_info(dev); 9754 } else { 9755 udp_tunnel_drop_rx_info(dev); 9756 } 9757 } 9758 9759 if (diff & NETIF_F_HW_VLAN_CTAG_FILTER) { 9760 if (features & NETIF_F_HW_VLAN_CTAG_FILTER) { 9761 dev->features = features; 9762 err |= vlan_get_rx_ctag_filter_info(dev); 9763 } else { 9764 vlan_drop_rx_ctag_filter_info(dev); 9765 } 9766 } 9767 9768 if (diff & NETIF_F_HW_VLAN_STAG_FILTER) { 9769 if (features & NETIF_F_HW_VLAN_STAG_FILTER) { 9770 dev->features = features; 9771 err |= vlan_get_rx_stag_filter_info(dev); 9772 } else { 9773 vlan_drop_rx_stag_filter_info(dev); 9774 } 9775 } 9776 9777 dev->features = features; 9778 } 9779 9780 return err < 0 ? 0 : 1; 9781 } 9782 9783 /** 9784 * netdev_update_features - recalculate device features 9785 * @dev: the device to check 9786 * 9787 * Recalculate dev->features set and send notifications if it 9788 * has changed. Should be called after driver or hardware dependent 9789 * conditions might have changed that influence the features. 9790 */ 9791 void netdev_update_features(struct net_device *dev) 9792 { 9793 if (__netdev_update_features(dev)) 9794 netdev_features_change(dev); 9795 } 9796 EXPORT_SYMBOL(netdev_update_features); 9797 9798 /** 9799 * netdev_change_features - recalculate device features 9800 * @dev: the device to check 9801 * 9802 * Recalculate dev->features set and send notifications even 9803 * if they have not changed. Should be called instead of 9804 * netdev_update_features() if also dev->vlan_features might 9805 * have changed to allow the changes to be propagated to stacked 9806 * VLAN devices. 9807 */ 9808 void netdev_change_features(struct net_device *dev) 9809 { 9810 __netdev_update_features(dev); 9811 netdev_features_change(dev); 9812 } 9813 EXPORT_SYMBOL(netdev_change_features); 9814 9815 /** 9816 * netif_stacked_transfer_operstate - transfer operstate 9817 * @rootdev: the root or lower level device to transfer state from 9818 * @dev: the device to transfer operstate to 9819 * 9820 * Transfer operational state from root to device. This is normally 9821 * called when a stacking relationship exists between the root 9822 * device and the device(a leaf device). 9823 */ 9824 void netif_stacked_transfer_operstate(const struct net_device *rootdev, 9825 struct net_device *dev) 9826 { 9827 if (rootdev->operstate == IF_OPER_DORMANT) 9828 netif_dormant_on(dev); 9829 else 9830 netif_dormant_off(dev); 9831 9832 if (rootdev->operstate == IF_OPER_TESTING) 9833 netif_testing_on(dev); 9834 else 9835 netif_testing_off(dev); 9836 9837 if (netif_carrier_ok(rootdev)) 9838 netif_carrier_on(dev); 9839 else 9840 netif_carrier_off(dev); 9841 } 9842 EXPORT_SYMBOL(netif_stacked_transfer_operstate); 9843 9844 static int netif_alloc_rx_queues(struct net_device *dev) 9845 { 9846 unsigned int i, count = dev->num_rx_queues; 9847 struct netdev_rx_queue *rx; 9848 size_t sz = count * sizeof(*rx); 9849 int err = 0; 9850 9851 BUG_ON(count < 1); 9852 9853 rx = kvzalloc(sz, GFP_KERNEL_ACCOUNT | __GFP_RETRY_MAYFAIL); 9854 if (!rx) 9855 return -ENOMEM; 9856 9857 dev->_rx = rx; 9858 9859 for (i = 0; i < count; i++) { 9860 rx[i].dev = dev; 9861 9862 /* XDP RX-queue setup */ 9863 err = xdp_rxq_info_reg(&rx[i].xdp_rxq, dev, i, 0); 9864 if (err < 0) 9865 goto err_rxq_info; 9866 } 9867 return 0; 9868 9869 err_rxq_info: 9870 /* Rollback successful reg's and free other resources */ 9871 while (i--) 9872 xdp_rxq_info_unreg(&rx[i].xdp_rxq); 9873 kvfree(dev->_rx); 9874 dev->_rx = NULL; 9875 return err; 9876 } 9877 9878 static void netif_free_rx_queues(struct net_device *dev) 9879 { 9880 unsigned int i, count = dev->num_rx_queues; 9881 9882 /* netif_alloc_rx_queues alloc failed, resources have been unreg'ed */ 9883 if (!dev->_rx) 9884 return; 9885 9886 for (i = 0; i < count; i++) 9887 xdp_rxq_info_unreg(&dev->_rx[i].xdp_rxq); 9888 9889 kvfree(dev->_rx); 9890 } 9891 9892 static void netdev_init_one_queue(struct net_device *dev, 9893 struct netdev_queue *queue, void *_unused) 9894 { 9895 /* Initialize queue lock */ 9896 spin_lock_init(&queue->_xmit_lock); 9897 netdev_set_xmit_lockdep_class(&queue->_xmit_lock, dev->type); 9898 queue->xmit_lock_owner = -1; 9899 netdev_queue_numa_node_write(queue, NUMA_NO_NODE); 9900 queue->dev = dev; 9901 #ifdef CONFIG_BQL 9902 dql_init(&queue->dql, HZ); 9903 #endif 9904 } 9905 9906 static void netif_free_tx_queues(struct net_device *dev) 9907 { 9908 kvfree(dev->_tx); 9909 } 9910 9911 static int netif_alloc_netdev_queues(struct net_device *dev) 9912 { 9913 unsigned int count = dev->num_tx_queues; 9914 struct netdev_queue *tx; 9915 size_t sz = count * sizeof(*tx); 9916 9917 if (count < 1 || count > 0xffff) 9918 return -EINVAL; 9919 9920 tx = kvzalloc(sz, GFP_KERNEL_ACCOUNT | __GFP_RETRY_MAYFAIL); 9921 if (!tx) 9922 return -ENOMEM; 9923 9924 dev->_tx = tx; 9925 9926 netdev_for_each_tx_queue(dev, netdev_init_one_queue, NULL); 9927 spin_lock_init(&dev->tx_global_lock); 9928 9929 return 0; 9930 } 9931 9932 void netif_tx_stop_all_queues(struct net_device *dev) 9933 { 9934 unsigned int i; 9935 9936 for (i = 0; i < dev->num_tx_queues; i++) { 9937 struct netdev_queue *txq = netdev_get_tx_queue(dev, i); 9938 9939 netif_tx_stop_queue(txq); 9940 } 9941 } 9942 EXPORT_SYMBOL(netif_tx_stop_all_queues); 9943 9944 /** 9945 * register_netdevice() - register a network device 9946 * @dev: device to register 9947 * 9948 * Take a prepared network device structure and make it externally accessible. 9949 * A %NETDEV_REGISTER message is sent to the netdev notifier chain. 9950 * Callers must hold the rtnl lock - you may want register_netdev() 9951 * instead of this. 9952 */ 9953 int register_netdevice(struct net_device *dev) 9954 { 9955 int ret; 9956 struct net *net = dev_net(dev); 9957 9958 BUILD_BUG_ON(sizeof(netdev_features_t) * BITS_PER_BYTE < 9959 NETDEV_FEATURE_COUNT); 9960 BUG_ON(dev_boot_phase); 9961 ASSERT_RTNL(); 9962 9963 might_sleep(); 9964 9965 /* When net_device's are persistent, this will be fatal. */ 9966 BUG_ON(dev->reg_state != NETREG_UNINITIALIZED); 9967 BUG_ON(!net); 9968 9969 ret = ethtool_check_ops(dev->ethtool_ops); 9970 if (ret) 9971 return ret; 9972 9973 spin_lock_init(&dev->addr_list_lock); 9974 netdev_set_addr_lockdep_class(dev); 9975 9976 ret = dev_get_valid_name(net, dev, dev->name); 9977 if (ret < 0) 9978 goto out; 9979 9980 ret = -ENOMEM; 9981 dev->name_node = netdev_name_node_head_alloc(dev); 9982 if (!dev->name_node) 9983 goto out; 9984 9985 /* Init, if this function is available */ 9986 if (dev->netdev_ops->ndo_init) { 9987 ret = dev->netdev_ops->ndo_init(dev); 9988 if (ret) { 9989 if (ret > 0) 9990 ret = -EIO; 9991 goto err_free_name; 9992 } 9993 } 9994 9995 if (((dev->hw_features | dev->features) & 9996 NETIF_F_HW_VLAN_CTAG_FILTER) && 9997 (!dev->netdev_ops->ndo_vlan_rx_add_vid || 9998 !dev->netdev_ops->ndo_vlan_rx_kill_vid)) { 9999 netdev_WARN(dev, "Buggy VLAN acceleration in driver!\n"); 10000 ret = -EINVAL; 10001 goto err_uninit; 10002 } 10003 10004 ret = -EBUSY; 10005 if (!dev->ifindex) 10006 dev->ifindex = dev_new_index(net); 10007 else if (__dev_get_by_index(net, dev->ifindex)) 10008 goto err_uninit; 10009 10010 /* Transfer changeable features to wanted_features and enable 10011 * software offloads (GSO and GRO). 10012 */ 10013 dev->hw_features |= (NETIF_F_SOFT_FEATURES | NETIF_F_SOFT_FEATURES_OFF); 10014 dev->features |= NETIF_F_SOFT_FEATURES; 10015 10016 if (dev->udp_tunnel_nic_info) { 10017 dev->features |= NETIF_F_RX_UDP_TUNNEL_PORT; 10018 dev->hw_features |= NETIF_F_RX_UDP_TUNNEL_PORT; 10019 } 10020 10021 dev->wanted_features = dev->features & dev->hw_features; 10022 10023 if (!(dev->flags & IFF_LOOPBACK)) 10024 dev->hw_features |= NETIF_F_NOCACHE_COPY; 10025 10026 /* If IPv4 TCP segmentation offload is supported we should also 10027 * allow the device to enable segmenting the frame with the option 10028 * of ignoring a static IP ID value. This doesn't enable the 10029 * feature itself but allows the user to enable it later. 10030 */ 10031 if (dev->hw_features & NETIF_F_TSO) 10032 dev->hw_features |= NETIF_F_TSO_MANGLEID; 10033 if (dev->vlan_features & NETIF_F_TSO) 10034 dev->vlan_features |= NETIF_F_TSO_MANGLEID; 10035 if (dev->mpls_features & NETIF_F_TSO) 10036 dev->mpls_features |= NETIF_F_TSO_MANGLEID; 10037 if (dev->hw_enc_features & NETIF_F_TSO) 10038 dev->hw_enc_features |= NETIF_F_TSO_MANGLEID; 10039 10040 /* Make NETIF_F_HIGHDMA inheritable to VLAN devices. 10041 */ 10042 dev->vlan_features |= NETIF_F_HIGHDMA; 10043 10044 /* Make NETIF_F_SG inheritable to tunnel devices. 10045 */ 10046 dev->hw_enc_features |= NETIF_F_SG | NETIF_F_GSO_PARTIAL; 10047 10048 /* Make NETIF_F_SG inheritable to MPLS. 10049 */ 10050 dev->mpls_features |= NETIF_F_SG; 10051 10052 ret = call_netdevice_notifiers(NETDEV_POST_INIT, dev); 10053 ret = notifier_to_errno(ret); 10054 if (ret) 10055 goto err_uninit; 10056 10057 ret = netdev_register_kobject(dev); 10058 write_lock(&dev_base_lock); 10059 dev->reg_state = ret ? NETREG_UNREGISTERED : NETREG_REGISTERED; 10060 write_unlock(&dev_base_lock); 10061 if (ret) 10062 goto err_uninit_notify; 10063 10064 __netdev_update_features(dev); 10065 10066 /* 10067 * Default initial state at registry is that the 10068 * device is present. 10069 */ 10070 10071 set_bit(__LINK_STATE_PRESENT, &dev->state); 10072 10073 linkwatch_init_dev(dev); 10074 10075 dev_init_scheduler(dev); 10076 10077 netdev_hold(dev, &dev->dev_registered_tracker, GFP_KERNEL); 10078 list_netdevice(dev); 10079 10080 add_device_randomness(dev->dev_addr, dev->addr_len); 10081 10082 /* If the device has permanent device address, driver should 10083 * set dev_addr and also addr_assign_type should be set to 10084 * NET_ADDR_PERM (default value). 10085 */ 10086 if (dev->addr_assign_type == NET_ADDR_PERM) 10087 memcpy(dev->perm_addr, dev->dev_addr, dev->addr_len); 10088 10089 /* Notify protocols, that a new device appeared. */ 10090 ret = call_netdevice_notifiers(NETDEV_REGISTER, dev); 10091 ret = notifier_to_errno(ret); 10092 if (ret) { 10093 /* Expect explicit free_netdev() on failure */ 10094 dev->needs_free_netdev = false; 10095 unregister_netdevice_queue(dev, NULL); 10096 goto out; 10097 } 10098 /* 10099 * Prevent userspace races by waiting until the network 10100 * device is fully setup before sending notifications. 10101 */ 10102 if (!dev->rtnl_link_ops || 10103 dev->rtnl_link_state == RTNL_LINK_INITIALIZED) 10104 rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U, GFP_KERNEL, 0, NULL); 10105 10106 out: 10107 return ret; 10108 10109 err_uninit_notify: 10110 call_netdevice_notifiers(NETDEV_PRE_UNINIT, dev); 10111 err_uninit: 10112 if (dev->netdev_ops->ndo_uninit) 10113 dev->netdev_ops->ndo_uninit(dev); 10114 if (dev->priv_destructor) 10115 dev->priv_destructor(dev); 10116 err_free_name: 10117 netdev_name_node_free(dev->name_node); 10118 goto out; 10119 } 10120 EXPORT_SYMBOL(register_netdevice); 10121 10122 /** 10123 * init_dummy_netdev - init a dummy network device for NAPI 10124 * @dev: device to init 10125 * 10126 * This takes a network device structure and initialize the minimum 10127 * amount of fields so it can be used to schedule NAPI polls without 10128 * registering a full blown interface. This is to be used by drivers 10129 * that need to tie several hardware interfaces to a single NAPI 10130 * poll scheduler due to HW limitations. 10131 */ 10132 int init_dummy_netdev(struct net_device *dev) 10133 { 10134 /* Clear everything. Note we don't initialize spinlocks 10135 * are they aren't supposed to be taken by any of the 10136 * NAPI code and this dummy netdev is supposed to be 10137 * only ever used for NAPI polls 10138 */ 10139 memset(dev, 0, sizeof(struct net_device)); 10140 10141 /* make sure we BUG if trying to hit standard 10142 * register/unregister code path 10143 */ 10144 dev->reg_state = NETREG_DUMMY; 10145 10146 /* NAPI wants this */ 10147 INIT_LIST_HEAD(&dev->napi_list); 10148 10149 /* a dummy interface is started by default */ 10150 set_bit(__LINK_STATE_PRESENT, &dev->state); 10151 set_bit(__LINK_STATE_START, &dev->state); 10152 10153 /* napi_busy_loop stats accounting wants this */ 10154 dev_net_set(dev, &init_net); 10155 10156 /* Note : We dont allocate pcpu_refcnt for dummy devices, 10157 * because users of this 'device' dont need to change 10158 * its refcount. 10159 */ 10160 10161 return 0; 10162 } 10163 EXPORT_SYMBOL_GPL(init_dummy_netdev); 10164 10165 10166 /** 10167 * register_netdev - register a network device 10168 * @dev: device to register 10169 * 10170 * Take a completed network device structure and add it to the kernel 10171 * interfaces. A %NETDEV_REGISTER message is sent to the netdev notifier 10172 * chain. 0 is returned on success. A negative errno code is returned 10173 * on a failure to set up the device, or if the name is a duplicate. 10174 * 10175 * This is a wrapper around register_netdevice that takes the rtnl semaphore 10176 * and expands the device name if you passed a format string to 10177 * alloc_netdev. 10178 */ 10179 int register_netdev(struct net_device *dev) 10180 { 10181 int err; 10182 10183 if (rtnl_lock_killable()) 10184 return -EINTR; 10185 err = register_netdevice(dev); 10186 rtnl_unlock(); 10187 return err; 10188 } 10189 EXPORT_SYMBOL(register_netdev); 10190 10191 int netdev_refcnt_read(const struct net_device *dev) 10192 { 10193 #ifdef CONFIG_PCPU_DEV_REFCNT 10194 int i, refcnt = 0; 10195 10196 for_each_possible_cpu(i) 10197 refcnt += *per_cpu_ptr(dev->pcpu_refcnt, i); 10198 return refcnt; 10199 #else 10200 return refcount_read(&dev->dev_refcnt); 10201 #endif 10202 } 10203 EXPORT_SYMBOL(netdev_refcnt_read); 10204 10205 int netdev_unregister_timeout_secs __read_mostly = 10; 10206 10207 #define WAIT_REFS_MIN_MSECS 1 10208 #define WAIT_REFS_MAX_MSECS 250 10209 /** 10210 * netdev_wait_allrefs_any - wait until all references are gone. 10211 * @list: list of net_devices to wait on 10212 * 10213 * This is called when unregistering network devices. 10214 * 10215 * Any protocol or device that holds a reference should register 10216 * for netdevice notification, and cleanup and put back the 10217 * reference if they receive an UNREGISTER event. 10218 * We can get stuck here if buggy protocols don't correctly 10219 * call dev_put. 10220 */ 10221 static struct net_device *netdev_wait_allrefs_any(struct list_head *list) 10222 { 10223 unsigned long rebroadcast_time, warning_time; 10224 struct net_device *dev; 10225 int wait = 0; 10226 10227 rebroadcast_time = warning_time = jiffies; 10228 10229 list_for_each_entry(dev, list, todo_list) 10230 if (netdev_refcnt_read(dev) == 1) 10231 return dev; 10232 10233 while (true) { 10234 if (time_after(jiffies, rebroadcast_time + 1 * HZ)) { 10235 rtnl_lock(); 10236 10237 /* Rebroadcast unregister notification */ 10238 list_for_each_entry(dev, list, todo_list) 10239 call_netdevice_notifiers(NETDEV_UNREGISTER, dev); 10240 10241 __rtnl_unlock(); 10242 rcu_barrier(); 10243 rtnl_lock(); 10244 10245 list_for_each_entry(dev, list, todo_list) 10246 if (test_bit(__LINK_STATE_LINKWATCH_PENDING, 10247 &dev->state)) { 10248 /* We must not have linkwatch events 10249 * pending on unregister. If this 10250 * happens, we simply run the queue 10251 * unscheduled, resulting in a noop 10252 * for this device. 10253 */ 10254 linkwatch_run_queue(); 10255 break; 10256 } 10257 10258 __rtnl_unlock(); 10259 10260 rebroadcast_time = jiffies; 10261 } 10262 10263 if (!wait) { 10264 rcu_barrier(); 10265 wait = WAIT_REFS_MIN_MSECS; 10266 } else { 10267 msleep(wait); 10268 wait = min(wait << 1, WAIT_REFS_MAX_MSECS); 10269 } 10270 10271 list_for_each_entry(dev, list, todo_list) 10272 if (netdev_refcnt_read(dev) == 1) 10273 return dev; 10274 10275 if (time_after(jiffies, warning_time + 10276 READ_ONCE(netdev_unregister_timeout_secs) * HZ)) { 10277 list_for_each_entry(dev, list, todo_list) { 10278 pr_emerg("unregister_netdevice: waiting for %s to become free. Usage count = %d\n", 10279 dev->name, netdev_refcnt_read(dev)); 10280 ref_tracker_dir_print(&dev->refcnt_tracker, 10); 10281 } 10282 10283 warning_time = jiffies; 10284 } 10285 } 10286 } 10287 10288 /* The sequence is: 10289 * 10290 * rtnl_lock(); 10291 * ... 10292 * register_netdevice(x1); 10293 * register_netdevice(x2); 10294 * ... 10295 * unregister_netdevice(y1); 10296 * unregister_netdevice(y2); 10297 * ... 10298 * rtnl_unlock(); 10299 * free_netdev(y1); 10300 * free_netdev(y2); 10301 * 10302 * We are invoked by rtnl_unlock(). 10303 * This allows us to deal with problems: 10304 * 1) We can delete sysfs objects which invoke hotplug 10305 * without deadlocking with linkwatch via keventd. 10306 * 2) Since we run with the RTNL semaphore not held, we can sleep 10307 * safely in order to wait for the netdev refcnt to drop to zero. 10308 * 10309 * We must not return until all unregister events added during 10310 * the interval the lock was held have been completed. 10311 */ 10312 void netdev_run_todo(void) 10313 { 10314 struct net_device *dev, *tmp; 10315 struct list_head list; 10316 #ifdef CONFIG_LOCKDEP 10317 struct list_head unlink_list; 10318 10319 list_replace_init(&net_unlink_list, &unlink_list); 10320 10321 while (!list_empty(&unlink_list)) { 10322 struct net_device *dev = list_first_entry(&unlink_list, 10323 struct net_device, 10324 unlink_list); 10325 list_del_init(&dev->unlink_list); 10326 dev->nested_level = dev->lower_level - 1; 10327 } 10328 #endif 10329 10330 /* Snapshot list, allow later requests */ 10331 list_replace_init(&net_todo_list, &list); 10332 10333 __rtnl_unlock(); 10334 10335 /* Wait for rcu callbacks to finish before next phase */ 10336 if (!list_empty(&list)) 10337 rcu_barrier(); 10338 10339 list_for_each_entry_safe(dev, tmp, &list, todo_list) { 10340 if (unlikely(dev->reg_state != NETREG_UNREGISTERING)) { 10341 netdev_WARN(dev, "run_todo but not unregistering\n"); 10342 list_del(&dev->todo_list); 10343 continue; 10344 } 10345 10346 write_lock(&dev_base_lock); 10347 dev->reg_state = NETREG_UNREGISTERED; 10348 write_unlock(&dev_base_lock); 10349 linkwatch_forget_dev(dev); 10350 } 10351 10352 while (!list_empty(&list)) { 10353 dev = netdev_wait_allrefs_any(&list); 10354 list_del(&dev->todo_list); 10355 10356 /* paranoia */ 10357 BUG_ON(netdev_refcnt_read(dev) != 1); 10358 BUG_ON(!list_empty(&dev->ptype_all)); 10359 BUG_ON(!list_empty(&dev->ptype_specific)); 10360 WARN_ON(rcu_access_pointer(dev->ip_ptr)); 10361 WARN_ON(rcu_access_pointer(dev->ip6_ptr)); 10362 10363 if (dev->priv_destructor) 10364 dev->priv_destructor(dev); 10365 if (dev->needs_free_netdev) 10366 free_netdev(dev); 10367 10368 if (atomic_dec_and_test(&dev_net(dev)->dev_unreg_count)) 10369 wake_up(&netdev_unregistering_wq); 10370 10371 /* Free network device */ 10372 kobject_put(&dev->dev.kobj); 10373 } 10374 } 10375 10376 /* Convert net_device_stats to rtnl_link_stats64. rtnl_link_stats64 has 10377 * all the same fields in the same order as net_device_stats, with only 10378 * the type differing, but rtnl_link_stats64 may have additional fields 10379 * at the end for newer counters. 10380 */ 10381 void netdev_stats_to_stats64(struct rtnl_link_stats64 *stats64, 10382 const struct net_device_stats *netdev_stats) 10383 { 10384 #if BITS_PER_LONG == 64 10385 BUILD_BUG_ON(sizeof(*stats64) < sizeof(*netdev_stats)); 10386 memcpy(stats64, netdev_stats, sizeof(*netdev_stats)); 10387 /* zero out counters that only exist in rtnl_link_stats64 */ 10388 memset((char *)stats64 + sizeof(*netdev_stats), 0, 10389 sizeof(*stats64) - sizeof(*netdev_stats)); 10390 #else 10391 size_t i, n = sizeof(*netdev_stats) / sizeof(unsigned long); 10392 const unsigned long *src = (const unsigned long *)netdev_stats; 10393 u64 *dst = (u64 *)stats64; 10394 10395 BUILD_BUG_ON(n > sizeof(*stats64) / sizeof(u64)); 10396 for (i = 0; i < n; i++) 10397 dst[i] = src[i]; 10398 /* zero out counters that only exist in rtnl_link_stats64 */ 10399 memset((char *)stats64 + n * sizeof(u64), 0, 10400 sizeof(*stats64) - n * sizeof(u64)); 10401 #endif 10402 } 10403 EXPORT_SYMBOL(netdev_stats_to_stats64); 10404 10405 struct net_device_core_stats __percpu *netdev_core_stats_alloc(struct net_device *dev) 10406 { 10407 struct net_device_core_stats __percpu *p; 10408 10409 p = alloc_percpu_gfp(struct net_device_core_stats, 10410 GFP_ATOMIC | __GFP_NOWARN); 10411 10412 if (p && cmpxchg(&dev->core_stats, NULL, p)) 10413 free_percpu(p); 10414 10415 /* This READ_ONCE() pairs with the cmpxchg() above */ 10416 return READ_ONCE(dev->core_stats); 10417 } 10418 EXPORT_SYMBOL(netdev_core_stats_alloc); 10419 10420 /** 10421 * dev_get_stats - get network device statistics 10422 * @dev: device to get statistics from 10423 * @storage: place to store stats 10424 * 10425 * Get network statistics from device. Return @storage. 10426 * The device driver may provide its own method by setting 10427 * dev->netdev_ops->get_stats64 or dev->netdev_ops->get_stats; 10428 * otherwise the internal statistics structure is used. 10429 */ 10430 struct rtnl_link_stats64 *dev_get_stats(struct net_device *dev, 10431 struct rtnl_link_stats64 *storage) 10432 { 10433 const struct net_device_ops *ops = dev->netdev_ops; 10434 const struct net_device_core_stats __percpu *p; 10435 10436 if (ops->ndo_get_stats64) { 10437 memset(storage, 0, sizeof(*storage)); 10438 ops->ndo_get_stats64(dev, storage); 10439 } else if (ops->ndo_get_stats) { 10440 netdev_stats_to_stats64(storage, ops->ndo_get_stats(dev)); 10441 } else { 10442 netdev_stats_to_stats64(storage, &dev->stats); 10443 } 10444 10445 /* This READ_ONCE() pairs with the write in netdev_core_stats_alloc() */ 10446 p = READ_ONCE(dev->core_stats); 10447 if (p) { 10448 const struct net_device_core_stats *core_stats; 10449 int i; 10450 10451 for_each_possible_cpu(i) { 10452 core_stats = per_cpu_ptr(p, i); 10453 storage->rx_dropped += READ_ONCE(core_stats->rx_dropped); 10454 storage->tx_dropped += READ_ONCE(core_stats->tx_dropped); 10455 storage->rx_nohandler += READ_ONCE(core_stats->rx_nohandler); 10456 storage->rx_otherhost_dropped += READ_ONCE(core_stats->rx_otherhost_dropped); 10457 } 10458 } 10459 return storage; 10460 } 10461 EXPORT_SYMBOL(dev_get_stats); 10462 10463 /** 10464 * dev_fetch_sw_netstats - get per-cpu network device statistics 10465 * @s: place to store stats 10466 * @netstats: per-cpu network stats to read from 10467 * 10468 * Read per-cpu network statistics and populate the related fields in @s. 10469 */ 10470 void dev_fetch_sw_netstats(struct rtnl_link_stats64 *s, 10471 const struct pcpu_sw_netstats __percpu *netstats) 10472 { 10473 int cpu; 10474 10475 for_each_possible_cpu(cpu) { 10476 u64 rx_packets, rx_bytes, tx_packets, tx_bytes; 10477 const struct pcpu_sw_netstats *stats; 10478 unsigned int start; 10479 10480 stats = per_cpu_ptr(netstats, cpu); 10481 do { 10482 start = u64_stats_fetch_begin(&stats->syncp); 10483 rx_packets = u64_stats_read(&stats->rx_packets); 10484 rx_bytes = u64_stats_read(&stats->rx_bytes); 10485 tx_packets = u64_stats_read(&stats->tx_packets); 10486 tx_bytes = u64_stats_read(&stats->tx_bytes); 10487 } while (u64_stats_fetch_retry(&stats->syncp, start)); 10488 10489 s->rx_packets += rx_packets; 10490 s->rx_bytes += rx_bytes; 10491 s->tx_packets += tx_packets; 10492 s->tx_bytes += tx_bytes; 10493 } 10494 } 10495 EXPORT_SYMBOL_GPL(dev_fetch_sw_netstats); 10496 10497 /** 10498 * dev_get_tstats64 - ndo_get_stats64 implementation 10499 * @dev: device to get statistics from 10500 * @s: place to store stats 10501 * 10502 * Populate @s from dev->stats and dev->tstats. Can be used as 10503 * ndo_get_stats64() callback. 10504 */ 10505 void dev_get_tstats64(struct net_device *dev, struct rtnl_link_stats64 *s) 10506 { 10507 netdev_stats_to_stats64(s, &dev->stats); 10508 dev_fetch_sw_netstats(s, dev->tstats); 10509 } 10510 EXPORT_SYMBOL_GPL(dev_get_tstats64); 10511 10512 struct netdev_queue *dev_ingress_queue_create(struct net_device *dev) 10513 { 10514 struct netdev_queue *queue = dev_ingress_queue(dev); 10515 10516 #ifdef CONFIG_NET_CLS_ACT 10517 if (queue) 10518 return queue; 10519 queue = kzalloc(sizeof(*queue), GFP_KERNEL); 10520 if (!queue) 10521 return NULL; 10522 netdev_init_one_queue(dev, queue, NULL); 10523 RCU_INIT_POINTER(queue->qdisc, &noop_qdisc); 10524 queue->qdisc_sleeping = &noop_qdisc; 10525 rcu_assign_pointer(dev->ingress_queue, queue); 10526 #endif 10527 return queue; 10528 } 10529 10530 static const struct ethtool_ops default_ethtool_ops; 10531 10532 void netdev_set_default_ethtool_ops(struct net_device *dev, 10533 const struct ethtool_ops *ops) 10534 { 10535 if (dev->ethtool_ops == &default_ethtool_ops) 10536 dev->ethtool_ops = ops; 10537 } 10538 EXPORT_SYMBOL_GPL(netdev_set_default_ethtool_ops); 10539 10540 void netdev_freemem(struct net_device *dev) 10541 { 10542 char *addr = (char *)dev - dev->padded; 10543 10544 kvfree(addr); 10545 } 10546 10547 /** 10548 * alloc_netdev_mqs - allocate network device 10549 * @sizeof_priv: size of private data to allocate space for 10550 * @name: device name format string 10551 * @name_assign_type: origin of device name 10552 * @setup: callback to initialize device 10553 * @txqs: the number of TX subqueues to allocate 10554 * @rxqs: the number of RX subqueues to allocate 10555 * 10556 * Allocates a struct net_device with private data area for driver use 10557 * and performs basic initialization. Also allocates subqueue structs 10558 * for each queue on the device. 10559 */ 10560 struct net_device *alloc_netdev_mqs(int sizeof_priv, const char *name, 10561 unsigned char name_assign_type, 10562 void (*setup)(struct net_device *), 10563 unsigned int txqs, unsigned int rxqs) 10564 { 10565 struct net_device *dev; 10566 unsigned int alloc_size; 10567 struct net_device *p; 10568 10569 BUG_ON(strlen(name) >= sizeof(dev->name)); 10570 10571 if (txqs < 1) { 10572 pr_err("alloc_netdev: Unable to allocate device with zero queues\n"); 10573 return NULL; 10574 } 10575 10576 if (rxqs < 1) { 10577 pr_err("alloc_netdev: Unable to allocate device with zero RX queues\n"); 10578 return NULL; 10579 } 10580 10581 alloc_size = sizeof(struct net_device); 10582 if (sizeof_priv) { 10583 /* ensure 32-byte alignment of private area */ 10584 alloc_size = ALIGN(alloc_size, NETDEV_ALIGN); 10585 alloc_size += sizeof_priv; 10586 } 10587 /* ensure 32-byte alignment of whole construct */ 10588 alloc_size += NETDEV_ALIGN - 1; 10589 10590 p = kvzalloc(alloc_size, GFP_KERNEL_ACCOUNT | __GFP_RETRY_MAYFAIL); 10591 if (!p) 10592 return NULL; 10593 10594 dev = PTR_ALIGN(p, NETDEV_ALIGN); 10595 dev->padded = (char *)dev - (char *)p; 10596 10597 ref_tracker_dir_init(&dev->refcnt_tracker, 128); 10598 #ifdef CONFIG_PCPU_DEV_REFCNT 10599 dev->pcpu_refcnt = alloc_percpu(int); 10600 if (!dev->pcpu_refcnt) 10601 goto free_dev; 10602 __dev_hold(dev); 10603 #else 10604 refcount_set(&dev->dev_refcnt, 1); 10605 #endif 10606 10607 if (dev_addr_init(dev)) 10608 goto free_pcpu; 10609 10610 dev_mc_init(dev); 10611 dev_uc_init(dev); 10612 10613 dev_net_set(dev, &init_net); 10614 10615 dev->gso_max_size = GSO_LEGACY_MAX_SIZE; 10616 dev->gso_max_segs = GSO_MAX_SEGS; 10617 dev->gro_max_size = GRO_LEGACY_MAX_SIZE; 10618 dev->tso_max_size = TSO_LEGACY_MAX_SIZE; 10619 dev->tso_max_segs = TSO_MAX_SEGS; 10620 dev->upper_level = 1; 10621 dev->lower_level = 1; 10622 #ifdef CONFIG_LOCKDEP 10623 dev->nested_level = 0; 10624 INIT_LIST_HEAD(&dev->unlink_list); 10625 #endif 10626 10627 INIT_LIST_HEAD(&dev->napi_list); 10628 INIT_LIST_HEAD(&dev->unreg_list); 10629 INIT_LIST_HEAD(&dev->close_list); 10630 INIT_LIST_HEAD(&dev->link_watch_list); 10631 INIT_LIST_HEAD(&dev->adj_list.upper); 10632 INIT_LIST_HEAD(&dev->adj_list.lower); 10633 INIT_LIST_HEAD(&dev->ptype_all); 10634 INIT_LIST_HEAD(&dev->ptype_specific); 10635 INIT_LIST_HEAD(&dev->net_notifier_list); 10636 #ifdef CONFIG_NET_SCHED 10637 hash_init(dev->qdisc_hash); 10638 #endif 10639 dev->priv_flags = IFF_XMIT_DST_RELEASE | IFF_XMIT_DST_RELEASE_PERM; 10640 setup(dev); 10641 10642 if (!dev->tx_queue_len) { 10643 dev->priv_flags |= IFF_NO_QUEUE; 10644 dev->tx_queue_len = DEFAULT_TX_QUEUE_LEN; 10645 } 10646 10647 dev->num_tx_queues = txqs; 10648 dev->real_num_tx_queues = txqs; 10649 if (netif_alloc_netdev_queues(dev)) 10650 goto free_all; 10651 10652 dev->num_rx_queues = rxqs; 10653 dev->real_num_rx_queues = rxqs; 10654 if (netif_alloc_rx_queues(dev)) 10655 goto free_all; 10656 10657 strcpy(dev->name, name); 10658 dev->name_assign_type = name_assign_type; 10659 dev->group = INIT_NETDEV_GROUP; 10660 if (!dev->ethtool_ops) 10661 dev->ethtool_ops = &default_ethtool_ops; 10662 10663 nf_hook_netdev_init(dev); 10664 10665 return dev; 10666 10667 free_all: 10668 free_netdev(dev); 10669 return NULL; 10670 10671 free_pcpu: 10672 #ifdef CONFIG_PCPU_DEV_REFCNT 10673 free_percpu(dev->pcpu_refcnt); 10674 free_dev: 10675 #endif 10676 netdev_freemem(dev); 10677 return NULL; 10678 } 10679 EXPORT_SYMBOL(alloc_netdev_mqs); 10680 10681 /** 10682 * free_netdev - free network device 10683 * @dev: device 10684 * 10685 * This function does the last stage of destroying an allocated device 10686 * interface. The reference to the device object is released. If this 10687 * is the last reference then it will be freed.Must be called in process 10688 * context. 10689 */ 10690 void free_netdev(struct net_device *dev) 10691 { 10692 struct napi_struct *p, *n; 10693 10694 might_sleep(); 10695 10696 /* When called immediately after register_netdevice() failed the unwind 10697 * handling may still be dismantling the device. Handle that case by 10698 * deferring the free. 10699 */ 10700 if (dev->reg_state == NETREG_UNREGISTERING) { 10701 ASSERT_RTNL(); 10702 dev->needs_free_netdev = true; 10703 return; 10704 } 10705 10706 netif_free_tx_queues(dev); 10707 netif_free_rx_queues(dev); 10708 10709 kfree(rcu_dereference_protected(dev->ingress_queue, 1)); 10710 10711 /* Flush device addresses */ 10712 dev_addr_flush(dev); 10713 10714 list_for_each_entry_safe(p, n, &dev->napi_list, dev_list) 10715 netif_napi_del(p); 10716 10717 ref_tracker_dir_exit(&dev->refcnt_tracker); 10718 #ifdef CONFIG_PCPU_DEV_REFCNT 10719 free_percpu(dev->pcpu_refcnt); 10720 dev->pcpu_refcnt = NULL; 10721 #endif 10722 free_percpu(dev->core_stats); 10723 dev->core_stats = NULL; 10724 free_percpu(dev->xdp_bulkq); 10725 dev->xdp_bulkq = NULL; 10726 10727 /* Compatibility with error handling in drivers */ 10728 if (dev->reg_state == NETREG_UNINITIALIZED) { 10729 netdev_freemem(dev); 10730 return; 10731 } 10732 10733 BUG_ON(dev->reg_state != NETREG_UNREGISTERED); 10734 dev->reg_state = NETREG_RELEASED; 10735 10736 /* will free via device release */ 10737 put_device(&dev->dev); 10738 } 10739 EXPORT_SYMBOL(free_netdev); 10740 10741 /** 10742 * synchronize_net - Synchronize with packet receive processing 10743 * 10744 * Wait for packets currently being received to be done. 10745 * Does not block later packets from starting. 10746 */ 10747 void synchronize_net(void) 10748 { 10749 might_sleep(); 10750 if (rtnl_is_locked()) 10751 synchronize_rcu_expedited(); 10752 else 10753 synchronize_rcu(); 10754 } 10755 EXPORT_SYMBOL(synchronize_net); 10756 10757 /** 10758 * unregister_netdevice_queue - remove device from the kernel 10759 * @dev: device 10760 * @head: list 10761 * 10762 * This function shuts down a device interface and removes it 10763 * from the kernel tables. 10764 * If head not NULL, device is queued to be unregistered later. 10765 * 10766 * Callers must hold the rtnl semaphore. You may want 10767 * unregister_netdev() instead of this. 10768 */ 10769 10770 void unregister_netdevice_queue(struct net_device *dev, struct list_head *head) 10771 { 10772 ASSERT_RTNL(); 10773 10774 if (head) { 10775 list_move_tail(&dev->unreg_list, head); 10776 } else { 10777 LIST_HEAD(single); 10778 10779 list_add(&dev->unreg_list, &single); 10780 unregister_netdevice_many(&single); 10781 } 10782 } 10783 EXPORT_SYMBOL(unregister_netdevice_queue); 10784 10785 void unregister_netdevice_many_notify(struct list_head *head, 10786 u32 portid, const struct nlmsghdr *nlh) 10787 { 10788 struct net_device *dev, *tmp; 10789 LIST_HEAD(close_head); 10790 10791 BUG_ON(dev_boot_phase); 10792 ASSERT_RTNL(); 10793 10794 if (list_empty(head)) 10795 return; 10796 10797 list_for_each_entry_safe(dev, tmp, head, unreg_list) { 10798 /* Some devices call without registering 10799 * for initialization unwind. Remove those 10800 * devices and proceed with the remaining. 10801 */ 10802 if (dev->reg_state == NETREG_UNINITIALIZED) { 10803 pr_debug("unregister_netdevice: device %s/%p never was registered\n", 10804 dev->name, dev); 10805 10806 WARN_ON(1); 10807 list_del(&dev->unreg_list); 10808 continue; 10809 } 10810 dev->dismantle = true; 10811 BUG_ON(dev->reg_state != NETREG_REGISTERED); 10812 } 10813 10814 /* If device is running, close it first. */ 10815 list_for_each_entry(dev, head, unreg_list) 10816 list_add_tail(&dev->close_list, &close_head); 10817 dev_close_many(&close_head, true); 10818 10819 list_for_each_entry(dev, head, unreg_list) { 10820 /* And unlink it from device chain. */ 10821 write_lock(&dev_base_lock); 10822 unlist_netdevice(dev, false); 10823 dev->reg_state = NETREG_UNREGISTERING; 10824 write_unlock(&dev_base_lock); 10825 } 10826 flush_all_backlogs(); 10827 10828 synchronize_net(); 10829 10830 list_for_each_entry(dev, head, unreg_list) { 10831 struct sk_buff *skb = NULL; 10832 10833 /* Shutdown queueing discipline. */ 10834 dev_shutdown(dev); 10835 10836 dev_xdp_uninstall(dev); 10837 10838 netdev_offload_xstats_disable_all(dev); 10839 10840 /* Notify protocols, that we are about to destroy 10841 * this device. They should clean all the things. 10842 */ 10843 call_netdevice_notifiers(NETDEV_UNREGISTER, dev); 10844 10845 if (!dev->rtnl_link_ops || 10846 dev->rtnl_link_state == RTNL_LINK_INITIALIZED) 10847 skb = rtmsg_ifinfo_build_skb(RTM_DELLINK, dev, ~0U, 0, 10848 GFP_KERNEL, NULL, 0, 10849 portid, nlmsg_seq(nlh)); 10850 10851 /* 10852 * Flush the unicast and multicast chains 10853 */ 10854 dev_uc_flush(dev); 10855 dev_mc_flush(dev); 10856 10857 netdev_name_node_alt_flush(dev); 10858 netdev_name_node_free(dev->name_node); 10859 10860 call_netdevice_notifiers(NETDEV_PRE_UNINIT, dev); 10861 10862 if (dev->netdev_ops->ndo_uninit) 10863 dev->netdev_ops->ndo_uninit(dev); 10864 10865 if (skb) 10866 rtmsg_ifinfo_send(skb, dev, GFP_KERNEL, portid, nlh); 10867 10868 /* Notifier chain MUST detach us all upper devices. */ 10869 WARN_ON(netdev_has_any_upper_dev(dev)); 10870 WARN_ON(netdev_has_any_lower_dev(dev)); 10871 10872 /* Remove entries from kobject tree */ 10873 netdev_unregister_kobject(dev); 10874 #ifdef CONFIG_XPS 10875 /* Remove XPS queueing entries */ 10876 netif_reset_xps_queues_gt(dev, 0); 10877 #endif 10878 } 10879 10880 synchronize_net(); 10881 10882 list_for_each_entry(dev, head, unreg_list) { 10883 netdev_put(dev, &dev->dev_registered_tracker); 10884 net_set_todo(dev); 10885 } 10886 10887 list_del(head); 10888 } 10889 10890 /** 10891 * unregister_netdevice_many - unregister many devices 10892 * @head: list of devices 10893 * 10894 * Note: As most callers use a stack allocated list_head, 10895 * we force a list_del() to make sure stack wont be corrupted later. 10896 */ 10897 void unregister_netdevice_many(struct list_head *head) 10898 { 10899 unregister_netdevice_many_notify(head, 0, NULL); 10900 } 10901 EXPORT_SYMBOL(unregister_netdevice_many); 10902 10903 /** 10904 * unregister_netdev - remove device from the kernel 10905 * @dev: device 10906 * 10907 * This function shuts down a device interface and removes it 10908 * from the kernel tables. 10909 * 10910 * This is just a wrapper for unregister_netdevice that takes 10911 * the rtnl semaphore. In general you want to use this and not 10912 * unregister_netdevice. 10913 */ 10914 void unregister_netdev(struct net_device *dev) 10915 { 10916 rtnl_lock(); 10917 unregister_netdevice(dev); 10918 rtnl_unlock(); 10919 } 10920 EXPORT_SYMBOL(unregister_netdev); 10921 10922 /** 10923 * __dev_change_net_namespace - move device to different nethost namespace 10924 * @dev: device 10925 * @net: network namespace 10926 * @pat: If not NULL name pattern to try if the current device name 10927 * is already taken in the destination network namespace. 10928 * @new_ifindex: If not zero, specifies device index in the target 10929 * namespace. 10930 * 10931 * This function shuts down a device interface and moves it 10932 * to a new network namespace. On success 0 is returned, on 10933 * a failure a netagive errno code is returned. 10934 * 10935 * Callers must hold the rtnl semaphore. 10936 */ 10937 10938 int __dev_change_net_namespace(struct net_device *dev, struct net *net, 10939 const char *pat, int new_ifindex) 10940 { 10941 struct net *net_old = dev_net(dev); 10942 int err, new_nsid; 10943 10944 ASSERT_RTNL(); 10945 10946 /* Don't allow namespace local devices to be moved. */ 10947 err = -EINVAL; 10948 if (dev->features & NETIF_F_NETNS_LOCAL) 10949 goto out; 10950 10951 /* Ensure the device has been registrered */ 10952 if (dev->reg_state != NETREG_REGISTERED) 10953 goto out; 10954 10955 /* Get out if there is nothing todo */ 10956 err = 0; 10957 if (net_eq(net_old, net)) 10958 goto out; 10959 10960 /* Pick the destination device name, and ensure 10961 * we can use it in the destination network namespace. 10962 */ 10963 err = -EEXIST; 10964 if (netdev_name_in_use(net, dev->name)) { 10965 /* We get here if we can't use the current device name */ 10966 if (!pat) 10967 goto out; 10968 err = dev_get_valid_name(net, dev, pat); 10969 if (err < 0) 10970 goto out; 10971 } 10972 10973 /* Check that new_ifindex isn't used yet. */ 10974 err = -EBUSY; 10975 if (new_ifindex && __dev_get_by_index(net, new_ifindex)) 10976 goto out; 10977 10978 /* 10979 * And now a mini version of register_netdevice unregister_netdevice. 10980 */ 10981 10982 /* If device is running close it first. */ 10983 dev_close(dev); 10984 10985 /* And unlink it from device chain */ 10986 unlist_netdevice(dev, true); 10987 10988 synchronize_net(); 10989 10990 /* Shutdown queueing discipline. */ 10991 dev_shutdown(dev); 10992 10993 /* Notify protocols, that we are about to destroy 10994 * this device. They should clean all the things. 10995 * 10996 * Note that dev->reg_state stays at NETREG_REGISTERED. 10997 * This is wanted because this way 8021q and macvlan know 10998 * the device is just moving and can keep their slaves up. 10999 */ 11000 call_netdevice_notifiers(NETDEV_UNREGISTER, dev); 11001 rcu_barrier(); 11002 11003 new_nsid = peernet2id_alloc(dev_net(dev), net, GFP_KERNEL); 11004 /* If there is an ifindex conflict assign a new one */ 11005 if (!new_ifindex) { 11006 if (__dev_get_by_index(net, dev->ifindex)) 11007 new_ifindex = dev_new_index(net); 11008 else 11009 new_ifindex = dev->ifindex; 11010 } 11011 11012 rtmsg_ifinfo_newnet(RTM_DELLINK, dev, ~0U, GFP_KERNEL, &new_nsid, 11013 new_ifindex); 11014 11015 /* 11016 * Flush the unicast and multicast chains 11017 */ 11018 dev_uc_flush(dev); 11019 dev_mc_flush(dev); 11020 11021 /* Send a netdev-removed uevent to the old namespace */ 11022 kobject_uevent(&dev->dev.kobj, KOBJ_REMOVE); 11023 netdev_adjacent_del_links(dev); 11024 11025 /* Move per-net netdevice notifiers that are following the netdevice */ 11026 move_netdevice_notifiers_dev_net(dev, net); 11027 11028 /* Actually switch the network namespace */ 11029 dev_net_set(dev, net); 11030 dev->ifindex = new_ifindex; 11031 11032 /* Send a netdev-add uevent to the new namespace */ 11033 kobject_uevent(&dev->dev.kobj, KOBJ_ADD); 11034 netdev_adjacent_add_links(dev); 11035 11036 /* Fixup kobjects */ 11037 err = device_rename(&dev->dev, dev->name); 11038 WARN_ON(err); 11039 11040 /* Adapt owner in case owning user namespace of target network 11041 * namespace is different from the original one. 11042 */ 11043 err = netdev_change_owner(dev, net_old, net); 11044 WARN_ON(err); 11045 11046 /* Add the device back in the hashes */ 11047 list_netdevice(dev); 11048 11049 /* Notify protocols, that a new device appeared. */ 11050 call_netdevice_notifiers(NETDEV_REGISTER, dev); 11051 11052 /* 11053 * Prevent userspace races by waiting until the network 11054 * device is fully setup before sending notifications. 11055 */ 11056 rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U, GFP_KERNEL, 0, NULL); 11057 11058 synchronize_net(); 11059 err = 0; 11060 out: 11061 return err; 11062 } 11063 EXPORT_SYMBOL_GPL(__dev_change_net_namespace); 11064 11065 static int dev_cpu_dead(unsigned int oldcpu) 11066 { 11067 struct sk_buff **list_skb; 11068 struct sk_buff *skb; 11069 unsigned int cpu; 11070 struct softnet_data *sd, *oldsd, *remsd = NULL; 11071 11072 local_irq_disable(); 11073 cpu = smp_processor_id(); 11074 sd = &per_cpu(softnet_data, cpu); 11075 oldsd = &per_cpu(softnet_data, oldcpu); 11076 11077 /* Find end of our completion_queue. */ 11078 list_skb = &sd->completion_queue; 11079 while (*list_skb) 11080 list_skb = &(*list_skb)->next; 11081 /* Append completion queue from offline CPU. */ 11082 *list_skb = oldsd->completion_queue; 11083 oldsd->completion_queue = NULL; 11084 11085 /* Append output queue from offline CPU. */ 11086 if (oldsd->output_queue) { 11087 *sd->output_queue_tailp = oldsd->output_queue; 11088 sd->output_queue_tailp = oldsd->output_queue_tailp; 11089 oldsd->output_queue = NULL; 11090 oldsd->output_queue_tailp = &oldsd->output_queue; 11091 } 11092 /* Append NAPI poll list from offline CPU, with one exception : 11093 * process_backlog() must be called by cpu owning percpu backlog. 11094 * We properly handle process_queue & input_pkt_queue later. 11095 */ 11096 while (!list_empty(&oldsd->poll_list)) { 11097 struct napi_struct *napi = list_first_entry(&oldsd->poll_list, 11098 struct napi_struct, 11099 poll_list); 11100 11101 list_del_init(&napi->poll_list); 11102 if (napi->poll == process_backlog) 11103 napi->state = 0; 11104 else 11105 ____napi_schedule(sd, napi); 11106 } 11107 11108 raise_softirq_irqoff(NET_TX_SOFTIRQ); 11109 local_irq_enable(); 11110 11111 #ifdef CONFIG_RPS 11112 remsd = oldsd->rps_ipi_list; 11113 oldsd->rps_ipi_list = NULL; 11114 #endif 11115 /* send out pending IPI's on offline CPU */ 11116 net_rps_send_ipi(remsd); 11117 11118 /* Process offline CPU's input_pkt_queue */ 11119 while ((skb = __skb_dequeue(&oldsd->process_queue))) { 11120 netif_rx(skb); 11121 input_queue_head_incr(oldsd); 11122 } 11123 while ((skb = skb_dequeue(&oldsd->input_pkt_queue))) { 11124 netif_rx(skb); 11125 input_queue_head_incr(oldsd); 11126 } 11127 11128 return 0; 11129 } 11130 11131 /** 11132 * netdev_increment_features - increment feature set by one 11133 * @all: current feature set 11134 * @one: new feature set 11135 * @mask: mask feature set 11136 * 11137 * Computes a new feature set after adding a device with feature set 11138 * @one to the master device with current feature set @all. Will not 11139 * enable anything that is off in @mask. Returns the new feature set. 11140 */ 11141 netdev_features_t netdev_increment_features(netdev_features_t all, 11142 netdev_features_t one, netdev_features_t mask) 11143 { 11144 if (mask & NETIF_F_HW_CSUM) 11145 mask |= NETIF_F_CSUM_MASK; 11146 mask |= NETIF_F_VLAN_CHALLENGED; 11147 11148 all |= one & (NETIF_F_ONE_FOR_ALL | NETIF_F_CSUM_MASK) & mask; 11149 all &= one | ~NETIF_F_ALL_FOR_ALL; 11150 11151 /* If one device supports hw checksumming, set for all. */ 11152 if (all & NETIF_F_HW_CSUM) 11153 all &= ~(NETIF_F_CSUM_MASK & ~NETIF_F_HW_CSUM); 11154 11155 return all; 11156 } 11157 EXPORT_SYMBOL(netdev_increment_features); 11158 11159 static struct hlist_head * __net_init netdev_create_hash(void) 11160 { 11161 int i; 11162 struct hlist_head *hash; 11163 11164 hash = kmalloc_array(NETDEV_HASHENTRIES, sizeof(*hash), GFP_KERNEL); 11165 if (hash != NULL) 11166 for (i = 0; i < NETDEV_HASHENTRIES; i++) 11167 INIT_HLIST_HEAD(&hash[i]); 11168 11169 return hash; 11170 } 11171 11172 /* Initialize per network namespace state */ 11173 static int __net_init netdev_init(struct net *net) 11174 { 11175 BUILD_BUG_ON(GRO_HASH_BUCKETS > 11176 8 * sizeof_field(struct napi_struct, gro_bitmask)); 11177 11178 INIT_LIST_HEAD(&net->dev_base_head); 11179 11180 net->dev_name_head = netdev_create_hash(); 11181 if (net->dev_name_head == NULL) 11182 goto err_name; 11183 11184 net->dev_index_head = netdev_create_hash(); 11185 if (net->dev_index_head == NULL) 11186 goto err_idx; 11187 11188 RAW_INIT_NOTIFIER_HEAD(&net->netdev_chain); 11189 11190 return 0; 11191 11192 err_idx: 11193 kfree(net->dev_name_head); 11194 err_name: 11195 return -ENOMEM; 11196 } 11197 11198 /** 11199 * netdev_drivername - network driver for the device 11200 * @dev: network device 11201 * 11202 * Determine network driver for device. 11203 */ 11204 const char *netdev_drivername(const struct net_device *dev) 11205 { 11206 const struct device_driver *driver; 11207 const struct device *parent; 11208 const char *empty = ""; 11209 11210 parent = dev->dev.parent; 11211 if (!parent) 11212 return empty; 11213 11214 driver = parent->driver; 11215 if (driver && driver->name) 11216 return driver->name; 11217 return empty; 11218 } 11219 11220 static void __netdev_printk(const char *level, const struct net_device *dev, 11221 struct va_format *vaf) 11222 { 11223 if (dev && dev->dev.parent) { 11224 dev_printk_emit(level[1] - '0', 11225 dev->dev.parent, 11226 "%s %s %s%s: %pV", 11227 dev_driver_string(dev->dev.parent), 11228 dev_name(dev->dev.parent), 11229 netdev_name(dev), netdev_reg_state(dev), 11230 vaf); 11231 } else if (dev) { 11232 printk("%s%s%s: %pV", 11233 level, netdev_name(dev), netdev_reg_state(dev), vaf); 11234 } else { 11235 printk("%s(NULL net_device): %pV", level, vaf); 11236 } 11237 } 11238 11239 void netdev_printk(const char *level, const struct net_device *dev, 11240 const char *format, ...) 11241 { 11242 struct va_format vaf; 11243 va_list args; 11244 11245 va_start(args, format); 11246 11247 vaf.fmt = format; 11248 vaf.va = &args; 11249 11250 __netdev_printk(level, dev, &vaf); 11251 11252 va_end(args); 11253 } 11254 EXPORT_SYMBOL(netdev_printk); 11255 11256 #define define_netdev_printk_level(func, level) \ 11257 void func(const struct net_device *dev, const char *fmt, ...) \ 11258 { \ 11259 struct va_format vaf; \ 11260 va_list args; \ 11261 \ 11262 va_start(args, fmt); \ 11263 \ 11264 vaf.fmt = fmt; \ 11265 vaf.va = &args; \ 11266 \ 11267 __netdev_printk(level, dev, &vaf); \ 11268 \ 11269 va_end(args); \ 11270 } \ 11271 EXPORT_SYMBOL(func); 11272 11273 define_netdev_printk_level(netdev_emerg, KERN_EMERG); 11274 define_netdev_printk_level(netdev_alert, KERN_ALERT); 11275 define_netdev_printk_level(netdev_crit, KERN_CRIT); 11276 define_netdev_printk_level(netdev_err, KERN_ERR); 11277 define_netdev_printk_level(netdev_warn, KERN_WARNING); 11278 define_netdev_printk_level(netdev_notice, KERN_NOTICE); 11279 define_netdev_printk_level(netdev_info, KERN_INFO); 11280 11281 static void __net_exit netdev_exit(struct net *net) 11282 { 11283 kfree(net->dev_name_head); 11284 kfree(net->dev_index_head); 11285 if (net != &init_net) 11286 WARN_ON_ONCE(!list_empty(&net->dev_base_head)); 11287 } 11288 11289 static struct pernet_operations __net_initdata netdev_net_ops = { 11290 .init = netdev_init, 11291 .exit = netdev_exit, 11292 }; 11293 11294 static void __net_exit default_device_exit_net(struct net *net) 11295 { 11296 struct net_device *dev, *aux; 11297 /* 11298 * Push all migratable network devices back to the 11299 * initial network namespace 11300 */ 11301 ASSERT_RTNL(); 11302 for_each_netdev_safe(net, dev, aux) { 11303 int err; 11304 char fb_name[IFNAMSIZ]; 11305 11306 /* Ignore unmoveable devices (i.e. loopback) */ 11307 if (dev->features & NETIF_F_NETNS_LOCAL) 11308 continue; 11309 11310 /* Leave virtual devices for the generic cleanup */ 11311 if (dev->rtnl_link_ops && !dev->rtnl_link_ops->netns_refund) 11312 continue; 11313 11314 /* Push remaining network devices to init_net */ 11315 snprintf(fb_name, IFNAMSIZ, "dev%d", dev->ifindex); 11316 if (netdev_name_in_use(&init_net, fb_name)) 11317 snprintf(fb_name, IFNAMSIZ, "dev%%d"); 11318 err = dev_change_net_namespace(dev, &init_net, fb_name); 11319 if (err) { 11320 pr_emerg("%s: failed to move %s to init_net: %d\n", 11321 __func__, dev->name, err); 11322 BUG(); 11323 } 11324 } 11325 } 11326 11327 static void __net_exit default_device_exit_batch(struct list_head *net_list) 11328 { 11329 /* At exit all network devices most be removed from a network 11330 * namespace. Do this in the reverse order of registration. 11331 * Do this across as many network namespaces as possible to 11332 * improve batching efficiency. 11333 */ 11334 struct net_device *dev; 11335 struct net *net; 11336 LIST_HEAD(dev_kill_list); 11337 11338 rtnl_lock(); 11339 list_for_each_entry(net, net_list, exit_list) { 11340 default_device_exit_net(net); 11341 cond_resched(); 11342 } 11343 11344 list_for_each_entry(net, net_list, exit_list) { 11345 for_each_netdev_reverse(net, dev) { 11346 if (dev->rtnl_link_ops && dev->rtnl_link_ops->dellink) 11347 dev->rtnl_link_ops->dellink(dev, &dev_kill_list); 11348 else 11349 unregister_netdevice_queue(dev, &dev_kill_list); 11350 } 11351 } 11352 unregister_netdevice_many(&dev_kill_list); 11353 rtnl_unlock(); 11354 } 11355 11356 static struct pernet_operations __net_initdata default_device_ops = { 11357 .exit_batch = default_device_exit_batch, 11358 }; 11359 11360 /* 11361 * Initialize the DEV module. At boot time this walks the device list and 11362 * unhooks any devices that fail to initialise (normally hardware not 11363 * present) and leaves us with a valid list of present and active devices. 11364 * 11365 */ 11366 11367 /* 11368 * This is called single threaded during boot, so no need 11369 * to take the rtnl semaphore. 11370 */ 11371 static int __init net_dev_init(void) 11372 { 11373 int i, rc = -ENOMEM; 11374 11375 BUG_ON(!dev_boot_phase); 11376 11377 if (dev_proc_init()) 11378 goto out; 11379 11380 if (netdev_kobject_init()) 11381 goto out; 11382 11383 INIT_LIST_HEAD(&ptype_all); 11384 for (i = 0; i < PTYPE_HASH_SIZE; i++) 11385 INIT_LIST_HEAD(&ptype_base[i]); 11386 11387 if (register_pernet_subsys(&netdev_net_ops)) 11388 goto out; 11389 11390 /* 11391 * Initialise the packet receive queues. 11392 */ 11393 11394 for_each_possible_cpu(i) { 11395 struct work_struct *flush = per_cpu_ptr(&flush_works, i); 11396 struct softnet_data *sd = &per_cpu(softnet_data, i); 11397 11398 INIT_WORK(flush, flush_backlog); 11399 11400 skb_queue_head_init(&sd->input_pkt_queue); 11401 skb_queue_head_init(&sd->process_queue); 11402 #ifdef CONFIG_XFRM_OFFLOAD 11403 skb_queue_head_init(&sd->xfrm_backlog); 11404 #endif 11405 INIT_LIST_HEAD(&sd->poll_list); 11406 sd->output_queue_tailp = &sd->output_queue; 11407 #ifdef CONFIG_RPS 11408 INIT_CSD(&sd->csd, rps_trigger_softirq, sd); 11409 sd->cpu = i; 11410 #endif 11411 INIT_CSD(&sd->defer_csd, trigger_rx_softirq, sd); 11412 spin_lock_init(&sd->defer_lock); 11413 11414 init_gro_hash(&sd->backlog); 11415 sd->backlog.poll = process_backlog; 11416 sd->backlog.weight = weight_p; 11417 } 11418 11419 dev_boot_phase = 0; 11420 11421 /* The loopback device is special if any other network devices 11422 * is present in a network namespace the loopback device must 11423 * be present. Since we now dynamically allocate and free the 11424 * loopback device ensure this invariant is maintained by 11425 * keeping the loopback device as the first device on the 11426 * list of network devices. Ensuring the loopback devices 11427 * is the first device that appears and the last network device 11428 * that disappears. 11429 */ 11430 if (register_pernet_device(&loopback_net_ops)) 11431 goto out; 11432 11433 if (register_pernet_device(&default_device_ops)) 11434 goto out; 11435 11436 open_softirq(NET_TX_SOFTIRQ, net_tx_action); 11437 open_softirq(NET_RX_SOFTIRQ, net_rx_action); 11438 11439 rc = cpuhp_setup_state_nocalls(CPUHP_NET_DEV_DEAD, "net/dev:dead", 11440 NULL, dev_cpu_dead); 11441 WARN_ON(rc < 0); 11442 rc = 0; 11443 out: 11444 return rc; 11445 } 11446 11447 subsys_initcall(net_dev_init); 11448