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