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/bitmap.h> 73 #include <linux/capability.h> 74 #include <linux/cpu.h> 75 #include <linux/types.h> 76 #include <linux/kernel.h> 77 #include <linux/hash.h> 78 #include <linux/slab.h> 79 #include <linux/sched.h> 80 #include <linux/sched/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 <net/tcx.h> 111 #include <linux/highmem.h> 112 #include <linux/init.h> 113 #include <linux/module.h> 114 #include <linux/netpoll.h> 115 #include <linux/rcupdate.h> 116 #include <linux/delay.h> 117 #include <net/iw_handler.h> 118 #include <asm/current.h> 119 #include <linux/audit.h> 120 #include <linux/dmaengine.h> 121 #include <linux/err.h> 122 #include <linux/ctype.h> 123 #include <linux/if_arp.h> 124 #include <linux/if_vlan.h> 125 #include <linux/ip.h> 126 #include <net/ip.h> 127 #include <net/mpls.h> 128 #include <linux/ipv6.h> 129 #include <linux/in.h> 130 #include <linux/jhash.h> 131 #include <linux/random.h> 132 #include <trace/events/napi.h> 133 #include <trace/events/net.h> 134 #include <trace/events/skb.h> 135 #include <trace/events/qdisc.h> 136 #include <trace/events/xdp.h> 137 #include <linux/inetdevice.h> 138 #include <linux/cpu_rmap.h> 139 #include <linux/static_key.h> 140 #include <linux/hashtable.h> 141 #include <linux/vmalloc.h> 142 #include <linux/if_macvlan.h> 143 #include <linux/errqueue.h> 144 #include <linux/hrtimer.h> 145 #include <linux/netfilter_netdev.h> 146 #include <linux/crash_dump.h> 147 #include <linux/sctp.h> 148 #include <net/udp_tunnel.h> 149 #include <linux/net_namespace.h> 150 #include <linux/indirect_call_wrapper.h> 151 #include <net/devlink.h> 152 #include <linux/pm_runtime.h> 153 #include <linux/prandom.h> 154 #include <linux/once_lite.h> 155 #include <net/netdev_rx_queue.h> 156 157 #include "dev.h" 158 #include "net-sysfs.h" 159 160 static DEFINE_SPINLOCK(ptype_lock); 161 struct list_head ptype_base[PTYPE_HASH_SIZE] __read_mostly; 162 struct list_head ptype_all __read_mostly; /* Taps */ 163 164 static int netif_rx_internal(struct sk_buff *skb); 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 kfree(name_node->name); 349 netdev_name_node_free(name_node); 350 } 351 352 int netdev_name_node_alt_destroy(struct net_device *dev, const char *name) 353 { 354 struct netdev_name_node *name_node; 355 struct net *net = dev_net(dev); 356 357 name_node = netdev_name_node_lookup(net, name); 358 if (!name_node) 359 return -ENOENT; 360 /* lookup might have found our primary name or a name belonging 361 * to another device. 362 */ 363 if (name_node == dev->name_node || name_node->dev != dev) 364 return -EINVAL; 365 366 netdev_name_node_del(name_node); 367 synchronize_rcu(); 368 __netdev_name_node_alt_destroy(name_node); 369 370 return 0; 371 } 372 373 static void netdev_name_node_alt_flush(struct net_device *dev) 374 { 375 struct netdev_name_node *name_node, *tmp; 376 377 list_for_each_entry_safe(name_node, tmp, &dev->name_node->list, list) 378 __netdev_name_node_alt_destroy(name_node); 379 } 380 381 /* Device list insertion */ 382 static void list_netdevice(struct net_device *dev) 383 { 384 struct netdev_name_node *name_node; 385 struct net *net = dev_net(dev); 386 387 ASSERT_RTNL(); 388 389 write_lock(&dev_base_lock); 390 list_add_tail_rcu(&dev->dev_list, &net->dev_base_head); 391 netdev_name_node_add(net, dev->name_node); 392 hlist_add_head_rcu(&dev->index_hlist, 393 dev_index_hash(net, dev->ifindex)); 394 write_unlock(&dev_base_lock); 395 396 netdev_for_each_altname(dev, name_node) 397 netdev_name_node_add(net, name_node); 398 399 /* We reserved the ifindex, this can't fail */ 400 WARN_ON(xa_store(&net->dev_by_index, dev->ifindex, dev, GFP_KERNEL)); 401 402 dev_base_seq_inc(net); 403 } 404 405 /* Device list removal 406 * caller must respect a RCU grace period before freeing/reusing dev 407 */ 408 static void unlist_netdevice(struct net_device *dev, bool lock) 409 { 410 struct netdev_name_node *name_node; 411 struct net *net = dev_net(dev); 412 413 ASSERT_RTNL(); 414 415 xa_erase(&net->dev_by_index, dev->ifindex); 416 417 netdev_for_each_altname(dev, name_node) 418 netdev_name_node_del(name_node); 419 420 /* Unlink dev from the device chain */ 421 if (lock) 422 write_lock(&dev_base_lock); 423 list_del_rcu(&dev->dev_list); 424 netdev_name_node_del(dev->name_node); 425 hlist_del_rcu(&dev->index_hlist); 426 if (lock) 427 write_unlock(&dev_base_lock); 428 429 dev_base_seq_inc(dev_net(dev)); 430 } 431 432 /* 433 * Our notifier list 434 */ 435 436 static RAW_NOTIFIER_HEAD(netdev_chain); 437 438 /* 439 * Device drivers call our routines to queue packets here. We empty the 440 * queue in the local softnet handler. 441 */ 442 443 DEFINE_PER_CPU_ALIGNED(struct softnet_data, softnet_data); 444 EXPORT_PER_CPU_SYMBOL(softnet_data); 445 446 #ifdef CONFIG_LOCKDEP 447 /* 448 * register_netdevice() inits txq->_xmit_lock and sets lockdep class 449 * according to dev->type 450 */ 451 static const unsigned short netdev_lock_type[] = { 452 ARPHRD_NETROM, ARPHRD_ETHER, ARPHRD_EETHER, ARPHRD_AX25, 453 ARPHRD_PRONET, ARPHRD_CHAOS, ARPHRD_IEEE802, ARPHRD_ARCNET, 454 ARPHRD_APPLETLK, ARPHRD_DLCI, ARPHRD_ATM, ARPHRD_METRICOM, 455 ARPHRD_IEEE1394, ARPHRD_EUI64, ARPHRD_INFINIBAND, ARPHRD_SLIP, 456 ARPHRD_CSLIP, ARPHRD_SLIP6, ARPHRD_CSLIP6, ARPHRD_RSRVD, 457 ARPHRD_ADAPT, ARPHRD_ROSE, ARPHRD_X25, ARPHRD_HWX25, 458 ARPHRD_PPP, ARPHRD_CISCO, ARPHRD_LAPB, ARPHRD_DDCMP, 459 ARPHRD_RAWHDLC, ARPHRD_TUNNEL, ARPHRD_TUNNEL6, ARPHRD_FRAD, 460 ARPHRD_SKIP, ARPHRD_LOOPBACK, ARPHRD_LOCALTLK, ARPHRD_FDDI, 461 ARPHRD_BIF, ARPHRD_SIT, ARPHRD_IPDDP, ARPHRD_IPGRE, 462 ARPHRD_PIMREG, ARPHRD_HIPPI, ARPHRD_ASH, ARPHRD_ECONET, 463 ARPHRD_IRDA, ARPHRD_FCPP, ARPHRD_FCAL, ARPHRD_FCPL, 464 ARPHRD_FCFABRIC, ARPHRD_IEEE80211, ARPHRD_IEEE80211_PRISM, 465 ARPHRD_IEEE80211_RADIOTAP, ARPHRD_PHONET, ARPHRD_PHONET_PIPE, 466 ARPHRD_IEEE802154, ARPHRD_VOID, ARPHRD_NONE}; 467 468 static const char *const netdev_lock_name[] = { 469 "_xmit_NETROM", "_xmit_ETHER", "_xmit_EETHER", "_xmit_AX25", 470 "_xmit_PRONET", "_xmit_CHAOS", "_xmit_IEEE802", "_xmit_ARCNET", 471 "_xmit_APPLETLK", "_xmit_DLCI", "_xmit_ATM", "_xmit_METRICOM", 472 "_xmit_IEEE1394", "_xmit_EUI64", "_xmit_INFINIBAND", "_xmit_SLIP", 473 "_xmit_CSLIP", "_xmit_SLIP6", "_xmit_CSLIP6", "_xmit_RSRVD", 474 "_xmit_ADAPT", "_xmit_ROSE", "_xmit_X25", "_xmit_HWX25", 475 "_xmit_PPP", "_xmit_CISCO", "_xmit_LAPB", "_xmit_DDCMP", 476 "_xmit_RAWHDLC", "_xmit_TUNNEL", "_xmit_TUNNEL6", "_xmit_FRAD", 477 "_xmit_SKIP", "_xmit_LOOPBACK", "_xmit_LOCALTLK", "_xmit_FDDI", 478 "_xmit_BIF", "_xmit_SIT", "_xmit_IPDDP", "_xmit_IPGRE", 479 "_xmit_PIMREG", "_xmit_HIPPI", "_xmit_ASH", "_xmit_ECONET", 480 "_xmit_IRDA", "_xmit_FCPP", "_xmit_FCAL", "_xmit_FCPL", 481 "_xmit_FCFABRIC", "_xmit_IEEE80211", "_xmit_IEEE80211_PRISM", 482 "_xmit_IEEE80211_RADIOTAP", "_xmit_PHONET", "_xmit_PHONET_PIPE", 483 "_xmit_IEEE802154", "_xmit_VOID", "_xmit_NONE"}; 484 485 static struct lock_class_key netdev_xmit_lock_key[ARRAY_SIZE(netdev_lock_type)]; 486 static struct lock_class_key netdev_addr_lock_key[ARRAY_SIZE(netdev_lock_type)]; 487 488 static inline unsigned short netdev_lock_pos(unsigned short dev_type) 489 { 490 int i; 491 492 for (i = 0; i < ARRAY_SIZE(netdev_lock_type); i++) 493 if (netdev_lock_type[i] == dev_type) 494 return i; 495 /* the last key is used by default */ 496 return ARRAY_SIZE(netdev_lock_type) - 1; 497 } 498 499 static inline void netdev_set_xmit_lockdep_class(spinlock_t *lock, 500 unsigned short dev_type) 501 { 502 int i; 503 504 i = netdev_lock_pos(dev_type); 505 lockdep_set_class_and_name(lock, &netdev_xmit_lock_key[i], 506 netdev_lock_name[i]); 507 } 508 509 static inline void netdev_set_addr_lockdep_class(struct net_device *dev) 510 { 511 int i; 512 513 i = netdev_lock_pos(dev->type); 514 lockdep_set_class_and_name(&dev->addr_list_lock, 515 &netdev_addr_lock_key[i], 516 netdev_lock_name[i]); 517 } 518 #else 519 static inline void netdev_set_xmit_lockdep_class(spinlock_t *lock, 520 unsigned short dev_type) 521 { 522 } 523 524 static inline void netdev_set_addr_lockdep_class(struct net_device *dev) 525 { 526 } 527 #endif 528 529 /******************************************************************************* 530 * 531 * Protocol management and registration routines 532 * 533 *******************************************************************************/ 534 535 536 /* 537 * Add a protocol ID to the list. Now that the input handler is 538 * smarter we can dispense with all the messy stuff that used to be 539 * here. 540 * 541 * BEWARE!!! Protocol handlers, mangling input packets, 542 * MUST BE last in hash buckets and checking protocol handlers 543 * MUST start from promiscuous ptype_all chain in net_bh. 544 * It is true now, do not change it. 545 * Explanation follows: if protocol handler, mangling packet, will 546 * be the first on list, it is not able to sense, that packet 547 * is cloned and should be copied-on-write, so that it will 548 * change it and subsequent readers will get broken packet. 549 * --ANK (980803) 550 */ 551 552 static inline struct list_head *ptype_head(const struct packet_type *pt) 553 { 554 if (pt->type == htons(ETH_P_ALL)) 555 return pt->dev ? &pt->dev->ptype_all : &ptype_all; 556 else 557 return pt->dev ? &pt->dev->ptype_specific : 558 &ptype_base[ntohs(pt->type) & PTYPE_HASH_MASK]; 559 } 560 561 /** 562 * dev_add_pack - add packet handler 563 * @pt: packet type declaration 564 * 565 * Add a protocol handler to the networking stack. The passed &packet_type 566 * is linked into kernel lists and may not be freed until it has been 567 * removed from the kernel lists. 568 * 569 * This call does not sleep therefore it can not 570 * guarantee all CPU's that are in middle of receiving packets 571 * will see the new packet type (until the next received packet). 572 */ 573 574 void dev_add_pack(struct packet_type *pt) 575 { 576 struct list_head *head = ptype_head(pt); 577 578 spin_lock(&ptype_lock); 579 list_add_rcu(&pt->list, head); 580 spin_unlock(&ptype_lock); 581 } 582 EXPORT_SYMBOL(dev_add_pack); 583 584 /** 585 * __dev_remove_pack - remove packet handler 586 * @pt: packet type declaration 587 * 588 * Remove a protocol handler that was previously added to the kernel 589 * protocol handlers by dev_add_pack(). The passed &packet_type is removed 590 * from the kernel lists and can be freed or reused once this function 591 * returns. 592 * 593 * The packet type might still be in use by receivers 594 * and must not be freed until after all the CPU's have gone 595 * through a quiescent state. 596 */ 597 void __dev_remove_pack(struct packet_type *pt) 598 { 599 struct list_head *head = ptype_head(pt); 600 struct packet_type *pt1; 601 602 spin_lock(&ptype_lock); 603 604 list_for_each_entry(pt1, head, list) { 605 if (pt == pt1) { 606 list_del_rcu(&pt->list); 607 goto out; 608 } 609 } 610 611 pr_warn("dev_remove_pack: %p not found\n", pt); 612 out: 613 spin_unlock(&ptype_lock); 614 } 615 EXPORT_SYMBOL(__dev_remove_pack); 616 617 /** 618 * dev_remove_pack - remove packet handler 619 * @pt: packet type declaration 620 * 621 * Remove a protocol handler that was previously added to the kernel 622 * protocol handlers by dev_add_pack(). The passed &packet_type is removed 623 * from the kernel lists and can be freed or reused once this function 624 * returns. 625 * 626 * This call sleeps to guarantee that no CPU is looking at the packet 627 * type after return. 628 */ 629 void dev_remove_pack(struct packet_type *pt) 630 { 631 __dev_remove_pack(pt); 632 633 synchronize_net(); 634 } 635 EXPORT_SYMBOL(dev_remove_pack); 636 637 638 /******************************************************************************* 639 * 640 * Device Interface Subroutines 641 * 642 *******************************************************************************/ 643 644 /** 645 * dev_get_iflink - get 'iflink' value of a interface 646 * @dev: targeted interface 647 * 648 * Indicates the ifindex the interface is linked to. 649 * Physical interfaces have the same 'ifindex' and 'iflink' values. 650 */ 651 652 int dev_get_iflink(const struct net_device *dev) 653 { 654 if (dev->netdev_ops && dev->netdev_ops->ndo_get_iflink) 655 return dev->netdev_ops->ndo_get_iflink(dev); 656 657 return dev->ifindex; 658 } 659 EXPORT_SYMBOL(dev_get_iflink); 660 661 /** 662 * dev_fill_metadata_dst - Retrieve tunnel egress information. 663 * @dev: targeted interface 664 * @skb: The packet. 665 * 666 * For better visibility of tunnel traffic OVS needs to retrieve 667 * egress tunnel information for a packet. Following API allows 668 * user to get this info. 669 */ 670 int dev_fill_metadata_dst(struct net_device *dev, struct sk_buff *skb) 671 { 672 struct ip_tunnel_info *info; 673 674 if (!dev->netdev_ops || !dev->netdev_ops->ndo_fill_metadata_dst) 675 return -EINVAL; 676 677 info = skb_tunnel_info_unclone(skb); 678 if (!info) 679 return -ENOMEM; 680 if (unlikely(!(info->mode & IP_TUNNEL_INFO_TX))) 681 return -EINVAL; 682 683 return dev->netdev_ops->ndo_fill_metadata_dst(dev, skb); 684 } 685 EXPORT_SYMBOL_GPL(dev_fill_metadata_dst); 686 687 static struct net_device_path *dev_fwd_path(struct net_device_path_stack *stack) 688 { 689 int k = stack->num_paths++; 690 691 if (WARN_ON_ONCE(k >= NET_DEVICE_PATH_STACK_MAX)) 692 return NULL; 693 694 return &stack->path[k]; 695 } 696 697 int dev_fill_forward_path(const struct net_device *dev, const u8 *daddr, 698 struct net_device_path_stack *stack) 699 { 700 const struct net_device *last_dev; 701 struct net_device_path_ctx ctx = { 702 .dev = dev, 703 }; 704 struct net_device_path *path; 705 int ret = 0; 706 707 memcpy(ctx.daddr, daddr, sizeof(ctx.daddr)); 708 stack->num_paths = 0; 709 while (ctx.dev && ctx.dev->netdev_ops->ndo_fill_forward_path) { 710 last_dev = ctx.dev; 711 path = dev_fwd_path(stack); 712 if (!path) 713 return -1; 714 715 memset(path, 0, sizeof(struct net_device_path)); 716 ret = ctx.dev->netdev_ops->ndo_fill_forward_path(&ctx, path); 717 if (ret < 0) 718 return -1; 719 720 if (WARN_ON_ONCE(last_dev == ctx.dev)) 721 return -1; 722 } 723 724 if (!ctx.dev) 725 return ret; 726 727 path = dev_fwd_path(stack); 728 if (!path) 729 return -1; 730 path->type = DEV_PATH_ETHERNET; 731 path->dev = ctx.dev; 732 733 return ret; 734 } 735 EXPORT_SYMBOL_GPL(dev_fill_forward_path); 736 737 /** 738 * __dev_get_by_name - find a device by its name 739 * @net: the applicable net namespace 740 * @name: name to find 741 * 742 * Find an interface by name. Must be called under RTNL semaphore 743 * or @dev_base_lock. If the name is found a pointer to the device 744 * is returned. If the name is not found then %NULL is returned. The 745 * reference counters are not incremented so the caller must be 746 * careful with locks. 747 */ 748 749 struct net_device *__dev_get_by_name(struct net *net, const char *name) 750 { 751 struct netdev_name_node *node_name; 752 753 node_name = netdev_name_node_lookup(net, name); 754 return node_name ? node_name->dev : NULL; 755 } 756 EXPORT_SYMBOL(__dev_get_by_name); 757 758 /** 759 * dev_get_by_name_rcu - find a device by its name 760 * @net: the applicable net namespace 761 * @name: name to find 762 * 763 * Find an interface by name. 764 * If the name is found a pointer to the device is returned. 765 * If the name is not found then %NULL is returned. 766 * The reference counters are not incremented so the caller must be 767 * careful with locks. The caller must hold RCU lock. 768 */ 769 770 struct net_device *dev_get_by_name_rcu(struct net *net, const char *name) 771 { 772 struct netdev_name_node *node_name; 773 774 node_name = netdev_name_node_lookup_rcu(net, name); 775 return node_name ? node_name->dev : NULL; 776 } 777 EXPORT_SYMBOL(dev_get_by_name_rcu); 778 779 /* Deprecated for new users, call netdev_get_by_name() instead */ 780 struct net_device *dev_get_by_name(struct net *net, const char *name) 781 { 782 struct net_device *dev; 783 784 rcu_read_lock(); 785 dev = dev_get_by_name_rcu(net, name); 786 dev_hold(dev); 787 rcu_read_unlock(); 788 return dev; 789 } 790 EXPORT_SYMBOL(dev_get_by_name); 791 792 /** 793 * netdev_get_by_name() - find a device by its name 794 * @net: the applicable net namespace 795 * @name: name to find 796 * @tracker: tracking object for the acquired reference 797 * @gfp: allocation flags for the tracker 798 * 799 * Find an interface by name. This can be called from any 800 * context and does its own locking. The returned handle has 801 * the usage count incremented and the caller must use netdev_put() to 802 * release it when it is no longer needed. %NULL is returned if no 803 * matching device is found. 804 */ 805 struct net_device *netdev_get_by_name(struct net *net, const char *name, 806 netdevice_tracker *tracker, gfp_t gfp) 807 { 808 struct net_device *dev; 809 810 dev = dev_get_by_name(net, name); 811 if (dev) 812 netdev_tracker_alloc(dev, tracker, gfp); 813 return dev; 814 } 815 EXPORT_SYMBOL(netdev_get_by_name); 816 817 /** 818 * __dev_get_by_index - find a device by its ifindex 819 * @net: the applicable net namespace 820 * @ifindex: index of device 821 * 822 * Search for an interface by index. Returns %NULL if the device 823 * is not found or a pointer to the device. The device has not 824 * had its reference counter increased so the caller must be careful 825 * about locking. The caller must hold either the RTNL semaphore 826 * or @dev_base_lock. 827 */ 828 829 struct net_device *__dev_get_by_index(struct net *net, int ifindex) 830 { 831 struct net_device *dev; 832 struct hlist_head *head = dev_index_hash(net, ifindex); 833 834 hlist_for_each_entry(dev, head, index_hlist) 835 if (dev->ifindex == ifindex) 836 return dev; 837 838 return NULL; 839 } 840 EXPORT_SYMBOL(__dev_get_by_index); 841 842 /** 843 * dev_get_by_index_rcu - find a device by its ifindex 844 * @net: the applicable net namespace 845 * @ifindex: index of device 846 * 847 * Search for an interface by index. Returns %NULL if the device 848 * is not found or a pointer to the device. The device has not 849 * had its reference counter increased so the caller must be careful 850 * about locking. The caller must hold RCU lock. 851 */ 852 853 struct net_device *dev_get_by_index_rcu(struct net *net, int ifindex) 854 { 855 struct net_device *dev; 856 struct hlist_head *head = dev_index_hash(net, ifindex); 857 858 hlist_for_each_entry_rcu(dev, head, index_hlist) 859 if (dev->ifindex == ifindex) 860 return dev; 861 862 return NULL; 863 } 864 EXPORT_SYMBOL(dev_get_by_index_rcu); 865 866 /* Deprecated for new users, call netdev_get_by_index() instead */ 867 struct net_device *dev_get_by_index(struct net *net, int ifindex) 868 { 869 struct net_device *dev; 870 871 rcu_read_lock(); 872 dev = dev_get_by_index_rcu(net, ifindex); 873 dev_hold(dev); 874 rcu_read_unlock(); 875 return dev; 876 } 877 EXPORT_SYMBOL(dev_get_by_index); 878 879 /** 880 * netdev_get_by_index() - find a device by its ifindex 881 * @net: the applicable net namespace 882 * @ifindex: index of device 883 * @tracker: tracking object for the acquired reference 884 * @gfp: allocation flags for the tracker 885 * 886 * Search for an interface by index. Returns NULL if the device 887 * is not found or a pointer to the device. The device returned has 888 * had a reference added and the pointer is safe until the user calls 889 * netdev_put() to indicate they have finished with it. 890 */ 891 struct net_device *netdev_get_by_index(struct net *net, int ifindex, 892 netdevice_tracker *tracker, gfp_t gfp) 893 { 894 struct net_device *dev; 895 896 dev = dev_get_by_index(net, ifindex); 897 if (dev) 898 netdev_tracker_alloc(dev, tracker, gfp); 899 return dev; 900 } 901 EXPORT_SYMBOL(netdev_get_by_index); 902 903 /** 904 * dev_get_by_napi_id - find a device by napi_id 905 * @napi_id: ID of the NAPI struct 906 * 907 * Search for an interface by NAPI ID. Returns %NULL if the device 908 * is not found or a pointer to the device. The device has not had 909 * its reference counter increased so the caller must be careful 910 * about locking. The caller must hold RCU lock. 911 */ 912 913 struct net_device *dev_get_by_napi_id(unsigned int napi_id) 914 { 915 struct napi_struct *napi; 916 917 WARN_ON_ONCE(!rcu_read_lock_held()); 918 919 if (napi_id < MIN_NAPI_ID) 920 return NULL; 921 922 napi = napi_by_id(napi_id); 923 924 return napi ? napi->dev : NULL; 925 } 926 EXPORT_SYMBOL(dev_get_by_napi_id); 927 928 /** 929 * netdev_get_name - get a netdevice name, knowing its ifindex. 930 * @net: network namespace 931 * @name: a pointer to the buffer where the name will be stored. 932 * @ifindex: the ifindex of the interface to get the name from. 933 */ 934 int netdev_get_name(struct net *net, char *name, int ifindex) 935 { 936 struct net_device *dev; 937 int ret; 938 939 down_read(&devnet_rename_sem); 940 rcu_read_lock(); 941 942 dev = dev_get_by_index_rcu(net, ifindex); 943 if (!dev) { 944 ret = -ENODEV; 945 goto out; 946 } 947 948 strcpy(name, dev->name); 949 950 ret = 0; 951 out: 952 rcu_read_unlock(); 953 up_read(&devnet_rename_sem); 954 return ret; 955 } 956 957 /** 958 * dev_getbyhwaddr_rcu - find a device by its hardware address 959 * @net: the applicable net namespace 960 * @type: media type of device 961 * @ha: hardware address 962 * 963 * Search for an interface by MAC address. Returns NULL if the device 964 * is not found or a pointer to the device. 965 * The caller must hold RCU or RTNL. 966 * The returned device has not had its ref count increased 967 * and the caller must therefore be careful about locking 968 * 969 */ 970 971 struct net_device *dev_getbyhwaddr_rcu(struct net *net, unsigned short type, 972 const char *ha) 973 { 974 struct net_device *dev; 975 976 for_each_netdev_rcu(net, dev) 977 if (dev->type == type && 978 !memcmp(dev->dev_addr, ha, dev->addr_len)) 979 return dev; 980 981 return NULL; 982 } 983 EXPORT_SYMBOL(dev_getbyhwaddr_rcu); 984 985 struct net_device *dev_getfirstbyhwtype(struct net *net, unsigned short type) 986 { 987 struct net_device *dev, *ret = NULL; 988 989 rcu_read_lock(); 990 for_each_netdev_rcu(net, dev) 991 if (dev->type == type) { 992 dev_hold(dev); 993 ret = dev; 994 break; 995 } 996 rcu_read_unlock(); 997 return ret; 998 } 999 EXPORT_SYMBOL(dev_getfirstbyhwtype); 1000 1001 /** 1002 * __dev_get_by_flags - find any device with given flags 1003 * @net: the applicable net namespace 1004 * @if_flags: IFF_* values 1005 * @mask: bitmask of bits in if_flags to check 1006 * 1007 * Search for any interface with the given flags. Returns NULL if a device 1008 * is not found or a pointer to the device. Must be called inside 1009 * rtnl_lock(), and result refcount is unchanged. 1010 */ 1011 1012 struct net_device *__dev_get_by_flags(struct net *net, unsigned short if_flags, 1013 unsigned short mask) 1014 { 1015 struct net_device *dev, *ret; 1016 1017 ASSERT_RTNL(); 1018 1019 ret = NULL; 1020 for_each_netdev(net, dev) { 1021 if (((dev->flags ^ if_flags) & mask) == 0) { 1022 ret = dev; 1023 break; 1024 } 1025 } 1026 return ret; 1027 } 1028 EXPORT_SYMBOL(__dev_get_by_flags); 1029 1030 /** 1031 * dev_valid_name - check if name is okay for network device 1032 * @name: name string 1033 * 1034 * Network device names need to be valid file names to 1035 * allow sysfs to work. We also disallow any kind of 1036 * whitespace. 1037 */ 1038 bool dev_valid_name(const char *name) 1039 { 1040 if (*name == '\0') 1041 return false; 1042 if (strnlen(name, IFNAMSIZ) == IFNAMSIZ) 1043 return false; 1044 if (!strcmp(name, ".") || !strcmp(name, "..")) 1045 return false; 1046 1047 while (*name) { 1048 if (*name == '/' || *name == ':' || isspace(*name)) 1049 return false; 1050 name++; 1051 } 1052 return true; 1053 } 1054 EXPORT_SYMBOL(dev_valid_name); 1055 1056 /** 1057 * __dev_alloc_name - allocate a name for a device 1058 * @net: network namespace to allocate the device name in 1059 * @name: name format string 1060 * @buf: scratch buffer and result name string 1061 * 1062 * Passed a format string - eg "lt%d" it will try and find a suitable 1063 * id. It scans list of devices to build up a free map, then chooses 1064 * the first empty slot. The caller must hold the dev_base or rtnl lock 1065 * while allocating the name and adding the device in order to avoid 1066 * duplicates. 1067 * Limited to bits_per_byte * page size devices (ie 32K on most platforms). 1068 * Returns the number of the unit assigned or a negative errno code. 1069 */ 1070 1071 static int __dev_alloc_name(struct net *net, const char *name, char *buf) 1072 { 1073 int i = 0; 1074 const char *p; 1075 const int max_netdevices = 8*PAGE_SIZE; 1076 unsigned long *inuse; 1077 struct net_device *d; 1078 1079 if (!dev_valid_name(name)) 1080 return -EINVAL; 1081 1082 p = strchr(name, '%'); 1083 if (p) { 1084 /* 1085 * Verify the string as this thing may have come from 1086 * the user. There must be either one "%d" and no other "%" 1087 * characters. 1088 */ 1089 if (p[1] != 'd' || strchr(p + 2, '%')) 1090 return -EINVAL; 1091 1092 /* Use one page as a bit array of possible slots */ 1093 inuse = bitmap_zalloc(max_netdevices, GFP_ATOMIC); 1094 if (!inuse) 1095 return -ENOMEM; 1096 1097 for_each_netdev(net, d) { 1098 struct netdev_name_node *name_node; 1099 1100 netdev_for_each_altname(d, name_node) { 1101 if (!sscanf(name_node->name, name, &i)) 1102 continue; 1103 if (i < 0 || i >= max_netdevices) 1104 continue; 1105 1106 /* avoid cases where sscanf is not exact inverse of printf */ 1107 snprintf(buf, IFNAMSIZ, name, i); 1108 if (!strncmp(buf, name_node->name, IFNAMSIZ)) 1109 __set_bit(i, inuse); 1110 } 1111 if (!sscanf(d->name, name, &i)) 1112 continue; 1113 if (i < 0 || i >= max_netdevices) 1114 continue; 1115 1116 /* avoid cases where sscanf is not exact inverse of printf */ 1117 snprintf(buf, IFNAMSIZ, name, i); 1118 if (!strncmp(buf, d->name, IFNAMSIZ)) 1119 __set_bit(i, inuse); 1120 } 1121 1122 i = find_first_zero_bit(inuse, max_netdevices); 1123 bitmap_free(inuse); 1124 } 1125 1126 snprintf(buf, IFNAMSIZ, name, i); 1127 if (!netdev_name_in_use(net, buf)) 1128 return i; 1129 1130 /* It is possible to run out of possible slots 1131 * when the name is long and there isn't enough space left 1132 * for the digits, or if all bits are used. 1133 */ 1134 return -ENFILE; 1135 } 1136 1137 static int dev_prep_valid_name(struct net *net, struct net_device *dev, 1138 const char *want_name, char *out_name) 1139 { 1140 int ret; 1141 1142 if (!dev_valid_name(want_name)) 1143 return -EINVAL; 1144 1145 if (strchr(want_name, '%')) { 1146 ret = __dev_alloc_name(net, want_name, out_name); 1147 return ret < 0 ? ret : 0; 1148 } else if (netdev_name_in_use(net, want_name)) { 1149 return -EEXIST; 1150 } else if (out_name != want_name) { 1151 strscpy(out_name, want_name, IFNAMSIZ); 1152 } 1153 1154 return 0; 1155 } 1156 1157 static int dev_alloc_name_ns(struct net *net, 1158 struct net_device *dev, 1159 const char *name) 1160 { 1161 char buf[IFNAMSIZ]; 1162 int ret; 1163 1164 BUG_ON(!net); 1165 ret = __dev_alloc_name(net, name, buf); 1166 if (ret >= 0) 1167 strscpy(dev->name, buf, IFNAMSIZ); 1168 return ret; 1169 } 1170 1171 /** 1172 * dev_alloc_name - allocate a name for a device 1173 * @dev: device 1174 * @name: name format string 1175 * 1176 * Passed a format string - eg "lt%d" it will try and find a suitable 1177 * id. It scans list of devices to build up a free map, then chooses 1178 * the first empty slot. The caller must hold the dev_base or rtnl lock 1179 * while allocating the name and adding the device in order to avoid 1180 * duplicates. 1181 * Limited to bits_per_byte * page size devices (ie 32K on most platforms). 1182 * Returns the number of the unit assigned or a negative errno code. 1183 */ 1184 1185 int dev_alloc_name(struct net_device *dev, const char *name) 1186 { 1187 return dev_alloc_name_ns(dev_net(dev), dev, name); 1188 } 1189 EXPORT_SYMBOL(dev_alloc_name); 1190 1191 static int dev_get_valid_name(struct net *net, struct net_device *dev, 1192 const char *name) 1193 { 1194 char buf[IFNAMSIZ]; 1195 int ret; 1196 1197 ret = dev_prep_valid_name(net, dev, name, buf); 1198 if (ret >= 0) 1199 strscpy(dev->name, buf, IFNAMSIZ); 1200 return ret; 1201 } 1202 1203 /** 1204 * dev_change_name - change name of a device 1205 * @dev: device 1206 * @newname: name (or format string) must be at least IFNAMSIZ 1207 * 1208 * Change name of a device, can pass format strings "eth%d". 1209 * for wildcarding. 1210 */ 1211 int dev_change_name(struct net_device *dev, const char *newname) 1212 { 1213 unsigned char old_assign_type; 1214 char oldname[IFNAMSIZ]; 1215 int err = 0; 1216 int ret; 1217 struct net *net; 1218 1219 ASSERT_RTNL(); 1220 BUG_ON(!dev_net(dev)); 1221 1222 net = dev_net(dev); 1223 1224 down_write(&devnet_rename_sem); 1225 1226 if (strncmp(newname, dev->name, IFNAMSIZ) == 0) { 1227 up_write(&devnet_rename_sem); 1228 return 0; 1229 } 1230 1231 memcpy(oldname, dev->name, IFNAMSIZ); 1232 1233 err = dev_get_valid_name(net, dev, newname); 1234 if (err < 0) { 1235 up_write(&devnet_rename_sem); 1236 return err; 1237 } 1238 1239 if (oldname[0] && !strchr(oldname, '%')) 1240 netdev_info(dev, "renamed from %s%s\n", oldname, 1241 dev->flags & IFF_UP ? " (while UP)" : ""); 1242 1243 old_assign_type = dev->name_assign_type; 1244 dev->name_assign_type = NET_NAME_RENAMED; 1245 1246 rollback: 1247 ret = device_rename(&dev->dev, dev->name); 1248 if (ret) { 1249 memcpy(dev->name, oldname, IFNAMSIZ); 1250 dev->name_assign_type = old_assign_type; 1251 up_write(&devnet_rename_sem); 1252 return ret; 1253 } 1254 1255 up_write(&devnet_rename_sem); 1256 1257 netdev_adjacent_rename_links(dev, oldname); 1258 1259 write_lock(&dev_base_lock); 1260 netdev_name_node_del(dev->name_node); 1261 write_unlock(&dev_base_lock); 1262 1263 synchronize_rcu(); 1264 1265 write_lock(&dev_base_lock); 1266 netdev_name_node_add(net, dev->name_node); 1267 write_unlock(&dev_base_lock); 1268 1269 ret = call_netdevice_notifiers(NETDEV_CHANGENAME, dev); 1270 ret = notifier_to_errno(ret); 1271 1272 if (ret) { 1273 /* err >= 0 after dev_alloc_name() or stores the first errno */ 1274 if (err >= 0) { 1275 err = ret; 1276 down_write(&devnet_rename_sem); 1277 memcpy(dev->name, oldname, IFNAMSIZ); 1278 memcpy(oldname, newname, IFNAMSIZ); 1279 dev->name_assign_type = old_assign_type; 1280 old_assign_type = NET_NAME_RENAMED; 1281 goto rollback; 1282 } else { 1283 netdev_err(dev, "name change rollback failed: %d\n", 1284 ret); 1285 } 1286 } 1287 1288 return err; 1289 } 1290 1291 /** 1292 * dev_set_alias - change ifalias of a device 1293 * @dev: device 1294 * @alias: name up to IFALIASZ 1295 * @len: limit of bytes to copy from info 1296 * 1297 * Set ifalias for a device, 1298 */ 1299 int dev_set_alias(struct net_device *dev, const char *alias, size_t len) 1300 { 1301 struct dev_ifalias *new_alias = NULL; 1302 1303 if (len >= IFALIASZ) 1304 return -EINVAL; 1305 1306 if (len) { 1307 new_alias = kmalloc(sizeof(*new_alias) + len + 1, GFP_KERNEL); 1308 if (!new_alias) 1309 return -ENOMEM; 1310 1311 memcpy(new_alias->ifalias, alias, len); 1312 new_alias->ifalias[len] = 0; 1313 } 1314 1315 mutex_lock(&ifalias_mutex); 1316 new_alias = rcu_replace_pointer(dev->ifalias, new_alias, 1317 mutex_is_locked(&ifalias_mutex)); 1318 mutex_unlock(&ifalias_mutex); 1319 1320 if (new_alias) 1321 kfree_rcu(new_alias, rcuhead); 1322 1323 return len; 1324 } 1325 EXPORT_SYMBOL(dev_set_alias); 1326 1327 /** 1328 * dev_get_alias - get ifalias of a device 1329 * @dev: device 1330 * @name: buffer to store name of ifalias 1331 * @len: size of buffer 1332 * 1333 * get ifalias for a device. Caller must make sure dev cannot go 1334 * away, e.g. rcu read lock or own a reference count to device. 1335 */ 1336 int dev_get_alias(const struct net_device *dev, char *name, size_t len) 1337 { 1338 const struct dev_ifalias *alias; 1339 int ret = 0; 1340 1341 rcu_read_lock(); 1342 alias = rcu_dereference(dev->ifalias); 1343 if (alias) 1344 ret = snprintf(name, len, "%s", alias->ifalias); 1345 rcu_read_unlock(); 1346 1347 return ret; 1348 } 1349 1350 /** 1351 * netdev_features_change - device changes features 1352 * @dev: device to cause notification 1353 * 1354 * Called to indicate a device has changed features. 1355 */ 1356 void netdev_features_change(struct net_device *dev) 1357 { 1358 call_netdevice_notifiers(NETDEV_FEAT_CHANGE, dev); 1359 } 1360 EXPORT_SYMBOL(netdev_features_change); 1361 1362 /** 1363 * netdev_state_change - device changes state 1364 * @dev: device to cause notification 1365 * 1366 * Called to indicate a device has changed state. This function calls 1367 * the notifier chains for netdev_chain and sends a NEWLINK message 1368 * to the routing socket. 1369 */ 1370 void netdev_state_change(struct net_device *dev) 1371 { 1372 if (dev->flags & IFF_UP) { 1373 struct netdev_notifier_change_info change_info = { 1374 .info.dev = dev, 1375 }; 1376 1377 call_netdevice_notifiers_info(NETDEV_CHANGE, 1378 &change_info.info); 1379 rtmsg_ifinfo(RTM_NEWLINK, dev, 0, GFP_KERNEL, 0, NULL); 1380 } 1381 } 1382 EXPORT_SYMBOL(netdev_state_change); 1383 1384 /** 1385 * __netdev_notify_peers - notify network peers about existence of @dev, 1386 * to be called when rtnl lock is already held. 1387 * @dev: network device 1388 * 1389 * Generate traffic such that interested network peers are aware of 1390 * @dev, such as by generating a gratuitous ARP. This may be used when 1391 * a device wants to inform the rest of the network about some sort of 1392 * reconfiguration such as a failover event or virtual machine 1393 * migration. 1394 */ 1395 void __netdev_notify_peers(struct net_device *dev) 1396 { 1397 ASSERT_RTNL(); 1398 call_netdevice_notifiers(NETDEV_NOTIFY_PEERS, dev); 1399 call_netdevice_notifiers(NETDEV_RESEND_IGMP, dev); 1400 } 1401 EXPORT_SYMBOL(__netdev_notify_peers); 1402 1403 /** 1404 * netdev_notify_peers - notify network peers about existence of @dev 1405 * @dev: network device 1406 * 1407 * Generate traffic such that interested network peers are aware of 1408 * @dev, such as by generating a gratuitous ARP. This may be used when 1409 * a device wants to inform the rest of the network about some sort of 1410 * reconfiguration such as a failover event or virtual machine 1411 * migration. 1412 */ 1413 void netdev_notify_peers(struct net_device *dev) 1414 { 1415 rtnl_lock(); 1416 __netdev_notify_peers(dev); 1417 rtnl_unlock(); 1418 } 1419 EXPORT_SYMBOL(netdev_notify_peers); 1420 1421 static int napi_threaded_poll(void *data); 1422 1423 static int napi_kthread_create(struct napi_struct *n) 1424 { 1425 int err = 0; 1426 1427 /* Create and wake up the kthread once to put it in 1428 * TASK_INTERRUPTIBLE mode to avoid the blocked task 1429 * warning and work with loadavg. 1430 */ 1431 n->thread = kthread_run(napi_threaded_poll, n, "napi/%s-%d", 1432 n->dev->name, n->napi_id); 1433 if (IS_ERR(n->thread)) { 1434 err = PTR_ERR(n->thread); 1435 pr_err("kthread_run failed with err %d\n", err); 1436 n->thread = NULL; 1437 } 1438 1439 return err; 1440 } 1441 1442 static int __dev_open(struct net_device *dev, struct netlink_ext_ack *extack) 1443 { 1444 const struct net_device_ops *ops = dev->netdev_ops; 1445 int ret; 1446 1447 ASSERT_RTNL(); 1448 dev_addr_check(dev); 1449 1450 if (!netif_device_present(dev)) { 1451 /* may be detached because parent is runtime-suspended */ 1452 if (dev->dev.parent) 1453 pm_runtime_resume(dev->dev.parent); 1454 if (!netif_device_present(dev)) 1455 return -ENODEV; 1456 } 1457 1458 /* Block netpoll from trying to do any rx path servicing. 1459 * If we don't do this there is a chance ndo_poll_controller 1460 * or ndo_poll may be running while we open the device 1461 */ 1462 netpoll_poll_disable(dev); 1463 1464 ret = call_netdevice_notifiers_extack(NETDEV_PRE_UP, dev, extack); 1465 ret = notifier_to_errno(ret); 1466 if (ret) 1467 return ret; 1468 1469 set_bit(__LINK_STATE_START, &dev->state); 1470 1471 if (ops->ndo_validate_addr) 1472 ret = ops->ndo_validate_addr(dev); 1473 1474 if (!ret && ops->ndo_open) 1475 ret = ops->ndo_open(dev); 1476 1477 netpoll_poll_enable(dev); 1478 1479 if (ret) 1480 clear_bit(__LINK_STATE_START, &dev->state); 1481 else { 1482 dev->flags |= IFF_UP; 1483 dev_set_rx_mode(dev); 1484 dev_activate(dev); 1485 add_device_randomness(dev->dev_addr, dev->addr_len); 1486 } 1487 1488 return ret; 1489 } 1490 1491 /** 1492 * dev_open - prepare an interface for use. 1493 * @dev: device to open 1494 * @extack: netlink extended ack 1495 * 1496 * Takes a device from down to up state. The device's private open 1497 * function is invoked and then the multicast lists are loaded. Finally 1498 * the device is moved into the up state and a %NETDEV_UP message is 1499 * sent to the netdev notifier chain. 1500 * 1501 * Calling this function on an active interface is a nop. On a failure 1502 * a negative errno code is returned. 1503 */ 1504 int dev_open(struct net_device *dev, struct netlink_ext_ack *extack) 1505 { 1506 int ret; 1507 1508 if (dev->flags & IFF_UP) 1509 return 0; 1510 1511 ret = __dev_open(dev, extack); 1512 if (ret < 0) 1513 return ret; 1514 1515 rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP | IFF_RUNNING, GFP_KERNEL, 0, NULL); 1516 call_netdevice_notifiers(NETDEV_UP, dev); 1517 1518 return ret; 1519 } 1520 EXPORT_SYMBOL(dev_open); 1521 1522 static void __dev_close_many(struct list_head *head) 1523 { 1524 struct net_device *dev; 1525 1526 ASSERT_RTNL(); 1527 might_sleep(); 1528 1529 list_for_each_entry(dev, head, close_list) { 1530 /* Temporarily disable netpoll until the interface is down */ 1531 netpoll_poll_disable(dev); 1532 1533 call_netdevice_notifiers(NETDEV_GOING_DOWN, dev); 1534 1535 clear_bit(__LINK_STATE_START, &dev->state); 1536 1537 /* Synchronize to scheduled poll. We cannot touch poll list, it 1538 * can be even on different cpu. So just clear netif_running(). 1539 * 1540 * dev->stop() will invoke napi_disable() on all of it's 1541 * napi_struct instances on this device. 1542 */ 1543 smp_mb__after_atomic(); /* Commit netif_running(). */ 1544 } 1545 1546 dev_deactivate_many(head); 1547 1548 list_for_each_entry(dev, head, close_list) { 1549 const struct net_device_ops *ops = dev->netdev_ops; 1550 1551 /* 1552 * Call the device specific close. This cannot fail. 1553 * Only if device is UP 1554 * 1555 * We allow it to be called even after a DETACH hot-plug 1556 * event. 1557 */ 1558 if (ops->ndo_stop) 1559 ops->ndo_stop(dev); 1560 1561 dev->flags &= ~IFF_UP; 1562 netpoll_poll_enable(dev); 1563 } 1564 } 1565 1566 static void __dev_close(struct net_device *dev) 1567 { 1568 LIST_HEAD(single); 1569 1570 list_add(&dev->close_list, &single); 1571 __dev_close_many(&single); 1572 list_del(&single); 1573 } 1574 1575 void dev_close_many(struct list_head *head, bool unlink) 1576 { 1577 struct net_device *dev, *tmp; 1578 1579 /* Remove the devices that don't need to be closed */ 1580 list_for_each_entry_safe(dev, tmp, head, close_list) 1581 if (!(dev->flags & IFF_UP)) 1582 list_del_init(&dev->close_list); 1583 1584 __dev_close_many(head); 1585 1586 list_for_each_entry_safe(dev, tmp, head, close_list) { 1587 rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP | IFF_RUNNING, GFP_KERNEL, 0, NULL); 1588 call_netdevice_notifiers(NETDEV_DOWN, dev); 1589 if (unlink) 1590 list_del_init(&dev->close_list); 1591 } 1592 } 1593 EXPORT_SYMBOL(dev_close_many); 1594 1595 /** 1596 * dev_close - shutdown an interface. 1597 * @dev: device to shutdown 1598 * 1599 * This function moves an active device into down state. A 1600 * %NETDEV_GOING_DOWN is sent to the netdev notifier chain. The device 1601 * is then deactivated and finally a %NETDEV_DOWN is sent to the notifier 1602 * chain. 1603 */ 1604 void dev_close(struct net_device *dev) 1605 { 1606 if (dev->flags & IFF_UP) { 1607 LIST_HEAD(single); 1608 1609 list_add(&dev->close_list, &single); 1610 dev_close_many(&single, true); 1611 list_del(&single); 1612 } 1613 } 1614 EXPORT_SYMBOL(dev_close); 1615 1616 1617 /** 1618 * dev_disable_lro - disable Large Receive Offload on a device 1619 * @dev: device 1620 * 1621 * Disable Large Receive Offload (LRO) on a net device. Must be 1622 * called under RTNL. This is needed if received packets may be 1623 * forwarded to another interface. 1624 */ 1625 void dev_disable_lro(struct net_device *dev) 1626 { 1627 struct net_device *lower_dev; 1628 struct list_head *iter; 1629 1630 dev->wanted_features &= ~NETIF_F_LRO; 1631 netdev_update_features(dev); 1632 1633 if (unlikely(dev->features & NETIF_F_LRO)) 1634 netdev_WARN(dev, "failed to disable LRO!\n"); 1635 1636 netdev_for_each_lower_dev(dev, lower_dev, iter) 1637 dev_disable_lro(lower_dev); 1638 } 1639 EXPORT_SYMBOL(dev_disable_lro); 1640 1641 /** 1642 * dev_disable_gro_hw - disable HW Generic Receive Offload on a device 1643 * @dev: device 1644 * 1645 * Disable HW Generic Receive Offload (GRO_HW) on a net device. Must be 1646 * called under RTNL. This is needed if Generic XDP is installed on 1647 * the device. 1648 */ 1649 static void dev_disable_gro_hw(struct net_device *dev) 1650 { 1651 dev->wanted_features &= ~NETIF_F_GRO_HW; 1652 netdev_update_features(dev); 1653 1654 if (unlikely(dev->features & NETIF_F_GRO_HW)) 1655 netdev_WARN(dev, "failed to disable GRO_HW!\n"); 1656 } 1657 1658 const char *netdev_cmd_to_name(enum netdev_cmd cmd) 1659 { 1660 #define N(val) \ 1661 case NETDEV_##val: \ 1662 return "NETDEV_" __stringify(val); 1663 switch (cmd) { 1664 N(UP) N(DOWN) N(REBOOT) N(CHANGE) N(REGISTER) N(UNREGISTER) 1665 N(CHANGEMTU) N(CHANGEADDR) N(GOING_DOWN) N(CHANGENAME) N(FEAT_CHANGE) 1666 N(BONDING_FAILOVER) N(PRE_UP) N(PRE_TYPE_CHANGE) N(POST_TYPE_CHANGE) 1667 N(POST_INIT) N(PRE_UNINIT) N(RELEASE) N(NOTIFY_PEERS) N(JOIN) 1668 N(CHANGEUPPER) N(RESEND_IGMP) N(PRECHANGEMTU) N(CHANGEINFODATA) 1669 N(BONDING_INFO) N(PRECHANGEUPPER) N(CHANGELOWERSTATE) 1670 N(UDP_TUNNEL_PUSH_INFO) N(UDP_TUNNEL_DROP_INFO) N(CHANGE_TX_QUEUE_LEN) 1671 N(CVLAN_FILTER_PUSH_INFO) N(CVLAN_FILTER_DROP_INFO) 1672 N(SVLAN_FILTER_PUSH_INFO) N(SVLAN_FILTER_DROP_INFO) 1673 N(PRE_CHANGEADDR) N(OFFLOAD_XSTATS_ENABLE) N(OFFLOAD_XSTATS_DISABLE) 1674 N(OFFLOAD_XSTATS_REPORT_USED) N(OFFLOAD_XSTATS_REPORT_DELTA) 1675 N(XDP_FEAT_CHANGE) 1676 } 1677 #undef N 1678 return "UNKNOWN_NETDEV_EVENT"; 1679 } 1680 EXPORT_SYMBOL_GPL(netdev_cmd_to_name); 1681 1682 static int call_netdevice_notifier(struct notifier_block *nb, unsigned long val, 1683 struct net_device *dev) 1684 { 1685 struct netdev_notifier_info info = { 1686 .dev = dev, 1687 }; 1688 1689 return nb->notifier_call(nb, val, &info); 1690 } 1691 1692 static int call_netdevice_register_notifiers(struct notifier_block *nb, 1693 struct net_device *dev) 1694 { 1695 int err; 1696 1697 err = call_netdevice_notifier(nb, NETDEV_REGISTER, dev); 1698 err = notifier_to_errno(err); 1699 if (err) 1700 return err; 1701 1702 if (!(dev->flags & IFF_UP)) 1703 return 0; 1704 1705 call_netdevice_notifier(nb, NETDEV_UP, dev); 1706 return 0; 1707 } 1708 1709 static void call_netdevice_unregister_notifiers(struct notifier_block *nb, 1710 struct net_device *dev) 1711 { 1712 if (dev->flags & IFF_UP) { 1713 call_netdevice_notifier(nb, NETDEV_GOING_DOWN, 1714 dev); 1715 call_netdevice_notifier(nb, NETDEV_DOWN, dev); 1716 } 1717 call_netdevice_notifier(nb, NETDEV_UNREGISTER, dev); 1718 } 1719 1720 static int call_netdevice_register_net_notifiers(struct notifier_block *nb, 1721 struct net *net) 1722 { 1723 struct net_device *dev; 1724 int err; 1725 1726 for_each_netdev(net, dev) { 1727 err = call_netdevice_register_notifiers(nb, dev); 1728 if (err) 1729 goto rollback; 1730 } 1731 return 0; 1732 1733 rollback: 1734 for_each_netdev_continue_reverse(net, dev) 1735 call_netdevice_unregister_notifiers(nb, dev); 1736 return err; 1737 } 1738 1739 static void call_netdevice_unregister_net_notifiers(struct notifier_block *nb, 1740 struct net *net) 1741 { 1742 struct net_device *dev; 1743 1744 for_each_netdev(net, dev) 1745 call_netdevice_unregister_notifiers(nb, dev); 1746 } 1747 1748 static int dev_boot_phase = 1; 1749 1750 /** 1751 * register_netdevice_notifier - register a network notifier block 1752 * @nb: notifier 1753 * 1754 * Register a notifier to be called when network device events occur. 1755 * The notifier passed is linked into the kernel structures and must 1756 * not be reused until it has been unregistered. A negative errno code 1757 * is returned on a failure. 1758 * 1759 * When registered all registration and up events are replayed 1760 * to the new notifier to allow device to have a race free 1761 * view of the network device list. 1762 */ 1763 1764 int register_netdevice_notifier(struct notifier_block *nb) 1765 { 1766 struct net *net; 1767 int err; 1768 1769 /* Close race with setup_net() and cleanup_net() */ 1770 down_write(&pernet_ops_rwsem); 1771 rtnl_lock(); 1772 err = raw_notifier_chain_register(&netdev_chain, nb); 1773 if (err) 1774 goto unlock; 1775 if (dev_boot_phase) 1776 goto unlock; 1777 for_each_net(net) { 1778 err = call_netdevice_register_net_notifiers(nb, net); 1779 if (err) 1780 goto rollback; 1781 } 1782 1783 unlock: 1784 rtnl_unlock(); 1785 up_write(&pernet_ops_rwsem); 1786 return err; 1787 1788 rollback: 1789 for_each_net_continue_reverse(net) 1790 call_netdevice_unregister_net_notifiers(nb, net); 1791 1792 raw_notifier_chain_unregister(&netdev_chain, nb); 1793 goto unlock; 1794 } 1795 EXPORT_SYMBOL(register_netdevice_notifier); 1796 1797 /** 1798 * unregister_netdevice_notifier - unregister a network notifier block 1799 * @nb: notifier 1800 * 1801 * Unregister a notifier previously registered by 1802 * register_netdevice_notifier(). The notifier is unlinked into the 1803 * kernel structures and may then be reused. A negative errno code 1804 * is returned on a failure. 1805 * 1806 * After unregistering unregister and down device events are synthesized 1807 * for all devices on the device list to the removed notifier to remove 1808 * the need for special case cleanup code. 1809 */ 1810 1811 int unregister_netdevice_notifier(struct notifier_block *nb) 1812 { 1813 struct net *net; 1814 int err; 1815 1816 /* Close race with setup_net() and cleanup_net() */ 1817 down_write(&pernet_ops_rwsem); 1818 rtnl_lock(); 1819 err = raw_notifier_chain_unregister(&netdev_chain, nb); 1820 if (err) 1821 goto unlock; 1822 1823 for_each_net(net) 1824 call_netdevice_unregister_net_notifiers(nb, net); 1825 1826 unlock: 1827 rtnl_unlock(); 1828 up_write(&pernet_ops_rwsem); 1829 return err; 1830 } 1831 EXPORT_SYMBOL(unregister_netdevice_notifier); 1832 1833 static int __register_netdevice_notifier_net(struct net *net, 1834 struct notifier_block *nb, 1835 bool ignore_call_fail) 1836 { 1837 int err; 1838 1839 err = raw_notifier_chain_register(&net->netdev_chain, nb); 1840 if (err) 1841 return err; 1842 if (dev_boot_phase) 1843 return 0; 1844 1845 err = call_netdevice_register_net_notifiers(nb, net); 1846 if (err && !ignore_call_fail) 1847 goto chain_unregister; 1848 1849 return 0; 1850 1851 chain_unregister: 1852 raw_notifier_chain_unregister(&net->netdev_chain, nb); 1853 return err; 1854 } 1855 1856 static int __unregister_netdevice_notifier_net(struct net *net, 1857 struct notifier_block *nb) 1858 { 1859 int err; 1860 1861 err = raw_notifier_chain_unregister(&net->netdev_chain, nb); 1862 if (err) 1863 return err; 1864 1865 call_netdevice_unregister_net_notifiers(nb, net); 1866 return 0; 1867 } 1868 1869 /** 1870 * register_netdevice_notifier_net - register a per-netns network notifier block 1871 * @net: network namespace 1872 * @nb: notifier 1873 * 1874 * Register a notifier to be called when network device events occur. 1875 * The notifier passed is linked into the kernel structures and must 1876 * not be reused until it has been unregistered. A negative errno code 1877 * is returned on a failure. 1878 * 1879 * When registered all registration and up events are replayed 1880 * to the new notifier to allow device to have a race free 1881 * view of the network device list. 1882 */ 1883 1884 int register_netdevice_notifier_net(struct net *net, struct notifier_block *nb) 1885 { 1886 int err; 1887 1888 rtnl_lock(); 1889 err = __register_netdevice_notifier_net(net, nb, false); 1890 rtnl_unlock(); 1891 return err; 1892 } 1893 EXPORT_SYMBOL(register_netdevice_notifier_net); 1894 1895 /** 1896 * unregister_netdevice_notifier_net - unregister a per-netns 1897 * network notifier block 1898 * @net: network namespace 1899 * @nb: notifier 1900 * 1901 * Unregister a notifier previously registered by 1902 * register_netdevice_notifier_net(). The notifier is unlinked from the 1903 * kernel structures and may then be reused. A negative errno code 1904 * is returned on a failure. 1905 * 1906 * After unregistering unregister and down device events are synthesized 1907 * for all devices on the device list to the removed notifier to remove 1908 * the need for special case cleanup code. 1909 */ 1910 1911 int unregister_netdevice_notifier_net(struct net *net, 1912 struct notifier_block *nb) 1913 { 1914 int err; 1915 1916 rtnl_lock(); 1917 err = __unregister_netdevice_notifier_net(net, nb); 1918 rtnl_unlock(); 1919 return err; 1920 } 1921 EXPORT_SYMBOL(unregister_netdevice_notifier_net); 1922 1923 static void __move_netdevice_notifier_net(struct net *src_net, 1924 struct net *dst_net, 1925 struct notifier_block *nb) 1926 { 1927 __unregister_netdevice_notifier_net(src_net, nb); 1928 __register_netdevice_notifier_net(dst_net, nb, true); 1929 } 1930 1931 int register_netdevice_notifier_dev_net(struct net_device *dev, 1932 struct notifier_block *nb, 1933 struct netdev_net_notifier *nn) 1934 { 1935 int err; 1936 1937 rtnl_lock(); 1938 err = __register_netdevice_notifier_net(dev_net(dev), nb, false); 1939 if (!err) { 1940 nn->nb = nb; 1941 list_add(&nn->list, &dev->net_notifier_list); 1942 } 1943 rtnl_unlock(); 1944 return err; 1945 } 1946 EXPORT_SYMBOL(register_netdevice_notifier_dev_net); 1947 1948 int unregister_netdevice_notifier_dev_net(struct net_device *dev, 1949 struct notifier_block *nb, 1950 struct netdev_net_notifier *nn) 1951 { 1952 int err; 1953 1954 rtnl_lock(); 1955 list_del(&nn->list); 1956 err = __unregister_netdevice_notifier_net(dev_net(dev), nb); 1957 rtnl_unlock(); 1958 return err; 1959 } 1960 EXPORT_SYMBOL(unregister_netdevice_notifier_dev_net); 1961 1962 static void move_netdevice_notifiers_dev_net(struct net_device *dev, 1963 struct net *net) 1964 { 1965 struct netdev_net_notifier *nn; 1966 1967 list_for_each_entry(nn, &dev->net_notifier_list, list) 1968 __move_netdevice_notifier_net(dev_net(dev), net, nn->nb); 1969 } 1970 1971 /** 1972 * call_netdevice_notifiers_info - call all network notifier blocks 1973 * @val: value passed unmodified to notifier function 1974 * @info: notifier information data 1975 * 1976 * Call all network notifier blocks. Parameters and return value 1977 * are as for raw_notifier_call_chain(). 1978 */ 1979 1980 int call_netdevice_notifiers_info(unsigned long val, 1981 struct netdev_notifier_info *info) 1982 { 1983 struct net *net = dev_net(info->dev); 1984 int ret; 1985 1986 ASSERT_RTNL(); 1987 1988 /* Run per-netns notifier block chain first, then run the global one. 1989 * Hopefully, one day, the global one is going to be removed after 1990 * all notifier block registrators get converted to be per-netns. 1991 */ 1992 ret = raw_notifier_call_chain(&net->netdev_chain, val, info); 1993 if (ret & NOTIFY_STOP_MASK) 1994 return ret; 1995 return raw_notifier_call_chain(&netdev_chain, val, info); 1996 } 1997 1998 /** 1999 * call_netdevice_notifiers_info_robust - call per-netns notifier blocks 2000 * for and rollback on error 2001 * @val_up: value passed unmodified to notifier function 2002 * @val_down: value passed unmodified to the notifier function when 2003 * recovering from an error on @val_up 2004 * @info: notifier information data 2005 * 2006 * Call all per-netns network notifier blocks, but not notifier blocks on 2007 * the global notifier chain. Parameters and return value are as for 2008 * raw_notifier_call_chain_robust(). 2009 */ 2010 2011 static int 2012 call_netdevice_notifiers_info_robust(unsigned long val_up, 2013 unsigned long val_down, 2014 struct netdev_notifier_info *info) 2015 { 2016 struct net *net = dev_net(info->dev); 2017 2018 ASSERT_RTNL(); 2019 2020 return raw_notifier_call_chain_robust(&net->netdev_chain, 2021 val_up, val_down, info); 2022 } 2023 2024 static int call_netdevice_notifiers_extack(unsigned long val, 2025 struct net_device *dev, 2026 struct netlink_ext_ack *extack) 2027 { 2028 struct netdev_notifier_info info = { 2029 .dev = dev, 2030 .extack = extack, 2031 }; 2032 2033 return call_netdevice_notifiers_info(val, &info); 2034 } 2035 2036 /** 2037 * call_netdevice_notifiers - call all network notifier blocks 2038 * @val: value passed unmodified to notifier function 2039 * @dev: net_device pointer passed unmodified to notifier function 2040 * 2041 * Call all network notifier blocks. Parameters and return value 2042 * are as for raw_notifier_call_chain(). 2043 */ 2044 2045 int call_netdevice_notifiers(unsigned long val, struct net_device *dev) 2046 { 2047 return call_netdevice_notifiers_extack(val, dev, NULL); 2048 } 2049 EXPORT_SYMBOL(call_netdevice_notifiers); 2050 2051 /** 2052 * call_netdevice_notifiers_mtu - call all network notifier blocks 2053 * @val: value passed unmodified to notifier function 2054 * @dev: net_device pointer passed unmodified to notifier function 2055 * @arg: additional u32 argument passed to the notifier function 2056 * 2057 * Call all network notifier blocks. Parameters and return value 2058 * are as for raw_notifier_call_chain(). 2059 */ 2060 static int call_netdevice_notifiers_mtu(unsigned long val, 2061 struct net_device *dev, u32 arg) 2062 { 2063 struct netdev_notifier_info_ext info = { 2064 .info.dev = dev, 2065 .ext.mtu = arg, 2066 }; 2067 2068 BUILD_BUG_ON(offsetof(struct netdev_notifier_info_ext, info) != 0); 2069 2070 return call_netdevice_notifiers_info(val, &info.info); 2071 } 2072 2073 #ifdef CONFIG_NET_INGRESS 2074 static DEFINE_STATIC_KEY_FALSE(ingress_needed_key); 2075 2076 void net_inc_ingress_queue(void) 2077 { 2078 static_branch_inc(&ingress_needed_key); 2079 } 2080 EXPORT_SYMBOL_GPL(net_inc_ingress_queue); 2081 2082 void net_dec_ingress_queue(void) 2083 { 2084 static_branch_dec(&ingress_needed_key); 2085 } 2086 EXPORT_SYMBOL_GPL(net_dec_ingress_queue); 2087 #endif 2088 2089 #ifdef CONFIG_NET_EGRESS 2090 static DEFINE_STATIC_KEY_FALSE(egress_needed_key); 2091 2092 void net_inc_egress_queue(void) 2093 { 2094 static_branch_inc(&egress_needed_key); 2095 } 2096 EXPORT_SYMBOL_GPL(net_inc_egress_queue); 2097 2098 void net_dec_egress_queue(void) 2099 { 2100 static_branch_dec(&egress_needed_key); 2101 } 2102 EXPORT_SYMBOL_GPL(net_dec_egress_queue); 2103 #endif 2104 2105 DEFINE_STATIC_KEY_FALSE(netstamp_needed_key); 2106 EXPORT_SYMBOL(netstamp_needed_key); 2107 #ifdef CONFIG_JUMP_LABEL 2108 static atomic_t netstamp_needed_deferred; 2109 static atomic_t netstamp_wanted; 2110 static void netstamp_clear(struct work_struct *work) 2111 { 2112 int deferred = atomic_xchg(&netstamp_needed_deferred, 0); 2113 int wanted; 2114 2115 wanted = atomic_add_return(deferred, &netstamp_wanted); 2116 if (wanted > 0) 2117 static_branch_enable(&netstamp_needed_key); 2118 else 2119 static_branch_disable(&netstamp_needed_key); 2120 } 2121 static DECLARE_WORK(netstamp_work, netstamp_clear); 2122 #endif 2123 2124 void net_enable_timestamp(void) 2125 { 2126 #ifdef CONFIG_JUMP_LABEL 2127 int wanted = atomic_read(&netstamp_wanted); 2128 2129 while (wanted > 0) { 2130 if (atomic_try_cmpxchg(&netstamp_wanted, &wanted, wanted + 1)) 2131 return; 2132 } 2133 atomic_inc(&netstamp_needed_deferred); 2134 schedule_work(&netstamp_work); 2135 #else 2136 static_branch_inc(&netstamp_needed_key); 2137 #endif 2138 } 2139 EXPORT_SYMBOL(net_enable_timestamp); 2140 2141 void net_disable_timestamp(void) 2142 { 2143 #ifdef CONFIG_JUMP_LABEL 2144 int wanted = atomic_read(&netstamp_wanted); 2145 2146 while (wanted > 1) { 2147 if (atomic_try_cmpxchg(&netstamp_wanted, &wanted, wanted - 1)) 2148 return; 2149 } 2150 atomic_dec(&netstamp_needed_deferred); 2151 schedule_work(&netstamp_work); 2152 #else 2153 static_branch_dec(&netstamp_needed_key); 2154 #endif 2155 } 2156 EXPORT_SYMBOL(net_disable_timestamp); 2157 2158 static inline void net_timestamp_set(struct sk_buff *skb) 2159 { 2160 skb->tstamp = 0; 2161 skb->mono_delivery_time = 0; 2162 if (static_branch_unlikely(&netstamp_needed_key)) 2163 skb->tstamp = ktime_get_real(); 2164 } 2165 2166 #define net_timestamp_check(COND, SKB) \ 2167 if (static_branch_unlikely(&netstamp_needed_key)) { \ 2168 if ((COND) && !(SKB)->tstamp) \ 2169 (SKB)->tstamp = ktime_get_real(); \ 2170 } \ 2171 2172 bool is_skb_forwardable(const struct net_device *dev, const struct sk_buff *skb) 2173 { 2174 return __is_skb_forwardable(dev, skb, true); 2175 } 2176 EXPORT_SYMBOL_GPL(is_skb_forwardable); 2177 2178 static int __dev_forward_skb2(struct net_device *dev, struct sk_buff *skb, 2179 bool check_mtu) 2180 { 2181 int ret = ____dev_forward_skb(dev, skb, check_mtu); 2182 2183 if (likely(!ret)) { 2184 skb->protocol = eth_type_trans(skb, dev); 2185 skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN); 2186 } 2187 2188 return ret; 2189 } 2190 2191 int __dev_forward_skb(struct net_device *dev, struct sk_buff *skb) 2192 { 2193 return __dev_forward_skb2(dev, skb, true); 2194 } 2195 EXPORT_SYMBOL_GPL(__dev_forward_skb); 2196 2197 /** 2198 * dev_forward_skb - loopback an skb to another netif 2199 * 2200 * @dev: destination network device 2201 * @skb: buffer to forward 2202 * 2203 * return values: 2204 * NET_RX_SUCCESS (no congestion) 2205 * NET_RX_DROP (packet was dropped, but freed) 2206 * 2207 * dev_forward_skb can be used for injecting an skb from the 2208 * start_xmit function of one device into the receive queue 2209 * of another device. 2210 * 2211 * The receiving device may be in another namespace, so 2212 * we have to clear all information in the skb that could 2213 * impact namespace isolation. 2214 */ 2215 int dev_forward_skb(struct net_device *dev, struct sk_buff *skb) 2216 { 2217 return __dev_forward_skb(dev, skb) ?: netif_rx_internal(skb); 2218 } 2219 EXPORT_SYMBOL_GPL(dev_forward_skb); 2220 2221 int dev_forward_skb_nomtu(struct net_device *dev, struct sk_buff *skb) 2222 { 2223 return __dev_forward_skb2(dev, skb, false) ?: netif_rx_internal(skb); 2224 } 2225 2226 static inline int deliver_skb(struct sk_buff *skb, 2227 struct packet_type *pt_prev, 2228 struct net_device *orig_dev) 2229 { 2230 if (unlikely(skb_orphan_frags_rx(skb, GFP_ATOMIC))) 2231 return -ENOMEM; 2232 refcount_inc(&skb->users); 2233 return pt_prev->func(skb, skb->dev, pt_prev, orig_dev); 2234 } 2235 2236 static inline void deliver_ptype_list_skb(struct sk_buff *skb, 2237 struct packet_type **pt, 2238 struct net_device *orig_dev, 2239 __be16 type, 2240 struct list_head *ptype_list) 2241 { 2242 struct packet_type *ptype, *pt_prev = *pt; 2243 2244 list_for_each_entry_rcu(ptype, ptype_list, list) { 2245 if (ptype->type != type) 2246 continue; 2247 if (pt_prev) 2248 deliver_skb(skb, pt_prev, orig_dev); 2249 pt_prev = ptype; 2250 } 2251 *pt = pt_prev; 2252 } 2253 2254 static inline bool skb_loop_sk(struct packet_type *ptype, struct sk_buff *skb) 2255 { 2256 if (!ptype->af_packet_priv || !skb->sk) 2257 return false; 2258 2259 if (ptype->id_match) 2260 return ptype->id_match(ptype, skb->sk); 2261 else if ((struct sock *)ptype->af_packet_priv == skb->sk) 2262 return true; 2263 2264 return false; 2265 } 2266 2267 /** 2268 * dev_nit_active - return true if any network interface taps are in use 2269 * 2270 * @dev: network device to check for the presence of taps 2271 */ 2272 bool dev_nit_active(struct net_device *dev) 2273 { 2274 return !list_empty(&ptype_all) || !list_empty(&dev->ptype_all); 2275 } 2276 EXPORT_SYMBOL_GPL(dev_nit_active); 2277 2278 /* 2279 * Support routine. Sends outgoing frames to any network 2280 * taps currently in use. 2281 */ 2282 2283 void dev_queue_xmit_nit(struct sk_buff *skb, struct net_device *dev) 2284 { 2285 struct packet_type *ptype; 2286 struct sk_buff *skb2 = NULL; 2287 struct packet_type *pt_prev = NULL; 2288 struct list_head *ptype_list = &ptype_all; 2289 2290 rcu_read_lock(); 2291 again: 2292 list_for_each_entry_rcu(ptype, ptype_list, list) { 2293 if (READ_ONCE(ptype->ignore_outgoing)) 2294 continue; 2295 2296 /* Never send packets back to the socket 2297 * they originated from - MvS (miquels@drinkel.ow.org) 2298 */ 2299 if (skb_loop_sk(ptype, skb)) 2300 continue; 2301 2302 if (pt_prev) { 2303 deliver_skb(skb2, pt_prev, skb->dev); 2304 pt_prev = ptype; 2305 continue; 2306 } 2307 2308 /* need to clone skb, done only once */ 2309 skb2 = skb_clone(skb, GFP_ATOMIC); 2310 if (!skb2) 2311 goto out_unlock; 2312 2313 net_timestamp_set(skb2); 2314 2315 /* skb->nh should be correctly 2316 * set by sender, so that the second statement is 2317 * just protection against buggy protocols. 2318 */ 2319 skb_reset_mac_header(skb2); 2320 2321 if (skb_network_header(skb2) < skb2->data || 2322 skb_network_header(skb2) > skb_tail_pointer(skb2)) { 2323 net_crit_ratelimited("protocol %04x is buggy, dev %s\n", 2324 ntohs(skb2->protocol), 2325 dev->name); 2326 skb_reset_network_header(skb2); 2327 } 2328 2329 skb2->transport_header = skb2->network_header; 2330 skb2->pkt_type = PACKET_OUTGOING; 2331 pt_prev = ptype; 2332 } 2333 2334 if (ptype_list == &ptype_all) { 2335 ptype_list = &dev->ptype_all; 2336 goto again; 2337 } 2338 out_unlock: 2339 if (pt_prev) { 2340 if (!skb_orphan_frags_rx(skb2, GFP_ATOMIC)) 2341 pt_prev->func(skb2, skb->dev, pt_prev, skb->dev); 2342 else 2343 kfree_skb(skb2); 2344 } 2345 rcu_read_unlock(); 2346 } 2347 EXPORT_SYMBOL_GPL(dev_queue_xmit_nit); 2348 2349 /** 2350 * netif_setup_tc - Handle tc mappings on real_num_tx_queues change 2351 * @dev: Network device 2352 * @txq: number of queues available 2353 * 2354 * If real_num_tx_queues is changed the tc mappings may no longer be 2355 * valid. To resolve this verify the tc mapping remains valid and if 2356 * not NULL the mapping. With no priorities mapping to this 2357 * offset/count pair it will no longer be used. In the worst case TC0 2358 * is invalid nothing can be done so disable priority mappings. If is 2359 * expected that drivers will fix this mapping if they can before 2360 * calling netif_set_real_num_tx_queues. 2361 */ 2362 static void netif_setup_tc(struct net_device *dev, unsigned int txq) 2363 { 2364 int i; 2365 struct netdev_tc_txq *tc = &dev->tc_to_txq[0]; 2366 2367 /* If TC0 is invalidated disable TC mapping */ 2368 if (tc->offset + tc->count > txq) { 2369 netdev_warn(dev, "Number of in use tx queues changed invalidating tc mappings. Priority traffic classification disabled!\n"); 2370 dev->num_tc = 0; 2371 return; 2372 } 2373 2374 /* Invalidated prio to tc mappings set to TC0 */ 2375 for (i = 1; i < TC_BITMASK + 1; i++) { 2376 int q = netdev_get_prio_tc_map(dev, i); 2377 2378 tc = &dev->tc_to_txq[q]; 2379 if (tc->offset + tc->count > txq) { 2380 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", 2381 i, q); 2382 netdev_set_prio_tc_map(dev, i, 0); 2383 } 2384 } 2385 } 2386 2387 int netdev_txq_to_tc(struct net_device *dev, unsigned int txq) 2388 { 2389 if (dev->num_tc) { 2390 struct netdev_tc_txq *tc = &dev->tc_to_txq[0]; 2391 int i; 2392 2393 /* walk through the TCs and see if it falls into any of them */ 2394 for (i = 0; i < TC_MAX_QUEUE; i++, tc++) { 2395 if ((txq - tc->offset) < tc->count) 2396 return i; 2397 } 2398 2399 /* didn't find it, just return -1 to indicate no match */ 2400 return -1; 2401 } 2402 2403 return 0; 2404 } 2405 EXPORT_SYMBOL(netdev_txq_to_tc); 2406 2407 #ifdef CONFIG_XPS 2408 static struct static_key xps_needed __read_mostly; 2409 static struct static_key xps_rxqs_needed __read_mostly; 2410 static DEFINE_MUTEX(xps_map_mutex); 2411 #define xmap_dereference(P) \ 2412 rcu_dereference_protected((P), lockdep_is_held(&xps_map_mutex)) 2413 2414 static bool remove_xps_queue(struct xps_dev_maps *dev_maps, 2415 struct xps_dev_maps *old_maps, int tci, u16 index) 2416 { 2417 struct xps_map *map = NULL; 2418 int pos; 2419 2420 map = xmap_dereference(dev_maps->attr_map[tci]); 2421 if (!map) 2422 return false; 2423 2424 for (pos = map->len; pos--;) { 2425 if (map->queues[pos] != index) 2426 continue; 2427 2428 if (map->len > 1) { 2429 map->queues[pos] = map->queues[--map->len]; 2430 break; 2431 } 2432 2433 if (old_maps) 2434 RCU_INIT_POINTER(old_maps->attr_map[tci], NULL); 2435 RCU_INIT_POINTER(dev_maps->attr_map[tci], NULL); 2436 kfree_rcu(map, rcu); 2437 return false; 2438 } 2439 2440 return true; 2441 } 2442 2443 static bool remove_xps_queue_cpu(struct net_device *dev, 2444 struct xps_dev_maps *dev_maps, 2445 int cpu, u16 offset, u16 count) 2446 { 2447 int num_tc = dev_maps->num_tc; 2448 bool active = false; 2449 int tci; 2450 2451 for (tci = cpu * num_tc; num_tc--; tci++) { 2452 int i, j; 2453 2454 for (i = count, j = offset; i--; j++) { 2455 if (!remove_xps_queue(dev_maps, NULL, tci, j)) 2456 break; 2457 } 2458 2459 active |= i < 0; 2460 } 2461 2462 return active; 2463 } 2464 2465 static void reset_xps_maps(struct net_device *dev, 2466 struct xps_dev_maps *dev_maps, 2467 enum xps_map_type type) 2468 { 2469 static_key_slow_dec_cpuslocked(&xps_needed); 2470 if (type == XPS_RXQS) 2471 static_key_slow_dec_cpuslocked(&xps_rxqs_needed); 2472 2473 RCU_INIT_POINTER(dev->xps_maps[type], NULL); 2474 2475 kfree_rcu(dev_maps, rcu); 2476 } 2477 2478 static void clean_xps_maps(struct net_device *dev, enum xps_map_type type, 2479 u16 offset, u16 count) 2480 { 2481 struct xps_dev_maps *dev_maps; 2482 bool active = false; 2483 int i, j; 2484 2485 dev_maps = xmap_dereference(dev->xps_maps[type]); 2486 if (!dev_maps) 2487 return; 2488 2489 for (j = 0; j < dev_maps->nr_ids; j++) 2490 active |= remove_xps_queue_cpu(dev, dev_maps, j, offset, count); 2491 if (!active) 2492 reset_xps_maps(dev, dev_maps, type); 2493 2494 if (type == XPS_CPUS) { 2495 for (i = offset + (count - 1); count--; i--) 2496 netdev_queue_numa_node_write( 2497 netdev_get_tx_queue(dev, i), NUMA_NO_NODE); 2498 } 2499 } 2500 2501 static void netif_reset_xps_queues(struct net_device *dev, u16 offset, 2502 u16 count) 2503 { 2504 if (!static_key_false(&xps_needed)) 2505 return; 2506 2507 cpus_read_lock(); 2508 mutex_lock(&xps_map_mutex); 2509 2510 if (static_key_false(&xps_rxqs_needed)) 2511 clean_xps_maps(dev, XPS_RXQS, offset, count); 2512 2513 clean_xps_maps(dev, XPS_CPUS, offset, count); 2514 2515 mutex_unlock(&xps_map_mutex); 2516 cpus_read_unlock(); 2517 } 2518 2519 static void netif_reset_xps_queues_gt(struct net_device *dev, u16 index) 2520 { 2521 netif_reset_xps_queues(dev, index, dev->num_tx_queues - index); 2522 } 2523 2524 static struct xps_map *expand_xps_map(struct xps_map *map, int attr_index, 2525 u16 index, bool is_rxqs_map) 2526 { 2527 struct xps_map *new_map; 2528 int alloc_len = XPS_MIN_MAP_ALLOC; 2529 int i, pos; 2530 2531 for (pos = 0; map && pos < map->len; pos++) { 2532 if (map->queues[pos] != index) 2533 continue; 2534 return map; 2535 } 2536 2537 /* Need to add tx-queue to this CPU's/rx-queue's existing map */ 2538 if (map) { 2539 if (pos < map->alloc_len) 2540 return map; 2541 2542 alloc_len = map->alloc_len * 2; 2543 } 2544 2545 /* Need to allocate new map to store tx-queue on this CPU's/rx-queue's 2546 * map 2547 */ 2548 if (is_rxqs_map) 2549 new_map = kzalloc(XPS_MAP_SIZE(alloc_len), GFP_KERNEL); 2550 else 2551 new_map = kzalloc_node(XPS_MAP_SIZE(alloc_len), GFP_KERNEL, 2552 cpu_to_node(attr_index)); 2553 if (!new_map) 2554 return NULL; 2555 2556 for (i = 0; i < pos; i++) 2557 new_map->queues[i] = map->queues[i]; 2558 new_map->alloc_len = alloc_len; 2559 new_map->len = pos; 2560 2561 return new_map; 2562 } 2563 2564 /* Copy xps maps at a given index */ 2565 static void xps_copy_dev_maps(struct xps_dev_maps *dev_maps, 2566 struct xps_dev_maps *new_dev_maps, int index, 2567 int tc, bool skip_tc) 2568 { 2569 int i, tci = index * dev_maps->num_tc; 2570 struct xps_map *map; 2571 2572 /* copy maps belonging to foreign traffic classes */ 2573 for (i = 0; i < dev_maps->num_tc; i++, tci++) { 2574 if (i == tc && skip_tc) 2575 continue; 2576 2577 /* fill in the new device map from the old device map */ 2578 map = xmap_dereference(dev_maps->attr_map[tci]); 2579 RCU_INIT_POINTER(new_dev_maps->attr_map[tci], map); 2580 } 2581 } 2582 2583 /* Must be called under cpus_read_lock */ 2584 int __netif_set_xps_queue(struct net_device *dev, const unsigned long *mask, 2585 u16 index, enum xps_map_type type) 2586 { 2587 struct xps_dev_maps *dev_maps, *new_dev_maps = NULL, *old_dev_maps = NULL; 2588 const unsigned long *online_mask = NULL; 2589 bool active = false, copy = false; 2590 int i, j, tci, numa_node_id = -2; 2591 int maps_sz, num_tc = 1, tc = 0; 2592 struct xps_map *map, *new_map; 2593 unsigned int nr_ids; 2594 2595 WARN_ON_ONCE(index >= dev->num_tx_queues); 2596 2597 if (dev->num_tc) { 2598 /* Do not allow XPS on subordinate device directly */ 2599 num_tc = dev->num_tc; 2600 if (num_tc < 0) 2601 return -EINVAL; 2602 2603 /* If queue belongs to subordinate dev use its map */ 2604 dev = netdev_get_tx_queue(dev, index)->sb_dev ? : dev; 2605 2606 tc = netdev_txq_to_tc(dev, index); 2607 if (tc < 0) 2608 return -EINVAL; 2609 } 2610 2611 mutex_lock(&xps_map_mutex); 2612 2613 dev_maps = xmap_dereference(dev->xps_maps[type]); 2614 if (type == XPS_RXQS) { 2615 maps_sz = XPS_RXQ_DEV_MAPS_SIZE(num_tc, dev->num_rx_queues); 2616 nr_ids = dev->num_rx_queues; 2617 } else { 2618 maps_sz = XPS_CPU_DEV_MAPS_SIZE(num_tc); 2619 if (num_possible_cpus() > 1) 2620 online_mask = cpumask_bits(cpu_online_mask); 2621 nr_ids = nr_cpu_ids; 2622 } 2623 2624 if (maps_sz < L1_CACHE_BYTES) 2625 maps_sz = L1_CACHE_BYTES; 2626 2627 /* The old dev_maps could be larger or smaller than the one we're 2628 * setting up now, as dev->num_tc or nr_ids could have been updated in 2629 * between. We could try to be smart, but let's be safe instead and only 2630 * copy foreign traffic classes if the two map sizes match. 2631 */ 2632 if (dev_maps && 2633 dev_maps->num_tc == num_tc && dev_maps->nr_ids == nr_ids) 2634 copy = true; 2635 2636 /* allocate memory for queue storage */ 2637 for (j = -1; j = netif_attrmask_next_and(j, online_mask, mask, nr_ids), 2638 j < nr_ids;) { 2639 if (!new_dev_maps) { 2640 new_dev_maps = kzalloc(maps_sz, GFP_KERNEL); 2641 if (!new_dev_maps) { 2642 mutex_unlock(&xps_map_mutex); 2643 return -ENOMEM; 2644 } 2645 2646 new_dev_maps->nr_ids = nr_ids; 2647 new_dev_maps->num_tc = num_tc; 2648 } 2649 2650 tci = j * num_tc + tc; 2651 map = copy ? xmap_dereference(dev_maps->attr_map[tci]) : NULL; 2652 2653 map = expand_xps_map(map, j, index, type == XPS_RXQS); 2654 if (!map) 2655 goto error; 2656 2657 RCU_INIT_POINTER(new_dev_maps->attr_map[tci], map); 2658 } 2659 2660 if (!new_dev_maps) 2661 goto out_no_new_maps; 2662 2663 if (!dev_maps) { 2664 /* Increment static keys at most once per type */ 2665 static_key_slow_inc_cpuslocked(&xps_needed); 2666 if (type == XPS_RXQS) 2667 static_key_slow_inc_cpuslocked(&xps_rxqs_needed); 2668 } 2669 2670 for (j = 0; j < nr_ids; j++) { 2671 bool skip_tc = false; 2672 2673 tci = j * num_tc + tc; 2674 if (netif_attr_test_mask(j, mask, nr_ids) && 2675 netif_attr_test_online(j, online_mask, nr_ids)) { 2676 /* add tx-queue to CPU/rx-queue maps */ 2677 int pos = 0; 2678 2679 skip_tc = true; 2680 2681 map = xmap_dereference(new_dev_maps->attr_map[tci]); 2682 while ((pos < map->len) && (map->queues[pos] != index)) 2683 pos++; 2684 2685 if (pos == map->len) 2686 map->queues[map->len++] = index; 2687 #ifdef CONFIG_NUMA 2688 if (type == XPS_CPUS) { 2689 if (numa_node_id == -2) 2690 numa_node_id = cpu_to_node(j); 2691 else if (numa_node_id != cpu_to_node(j)) 2692 numa_node_id = -1; 2693 } 2694 #endif 2695 } 2696 2697 if (copy) 2698 xps_copy_dev_maps(dev_maps, new_dev_maps, j, tc, 2699 skip_tc); 2700 } 2701 2702 rcu_assign_pointer(dev->xps_maps[type], new_dev_maps); 2703 2704 /* Cleanup old maps */ 2705 if (!dev_maps) 2706 goto out_no_old_maps; 2707 2708 for (j = 0; j < dev_maps->nr_ids; j++) { 2709 for (i = num_tc, tci = j * dev_maps->num_tc; i--; tci++) { 2710 map = xmap_dereference(dev_maps->attr_map[tci]); 2711 if (!map) 2712 continue; 2713 2714 if (copy) { 2715 new_map = xmap_dereference(new_dev_maps->attr_map[tci]); 2716 if (map == new_map) 2717 continue; 2718 } 2719 2720 RCU_INIT_POINTER(dev_maps->attr_map[tci], NULL); 2721 kfree_rcu(map, rcu); 2722 } 2723 } 2724 2725 old_dev_maps = dev_maps; 2726 2727 out_no_old_maps: 2728 dev_maps = new_dev_maps; 2729 active = true; 2730 2731 out_no_new_maps: 2732 if (type == XPS_CPUS) 2733 /* update Tx queue numa node */ 2734 netdev_queue_numa_node_write(netdev_get_tx_queue(dev, index), 2735 (numa_node_id >= 0) ? 2736 numa_node_id : NUMA_NO_NODE); 2737 2738 if (!dev_maps) 2739 goto out_no_maps; 2740 2741 /* removes tx-queue from unused CPUs/rx-queues */ 2742 for (j = 0; j < dev_maps->nr_ids; j++) { 2743 tci = j * dev_maps->num_tc; 2744 2745 for (i = 0; i < dev_maps->num_tc; i++, tci++) { 2746 if (i == tc && 2747 netif_attr_test_mask(j, mask, dev_maps->nr_ids) && 2748 netif_attr_test_online(j, online_mask, dev_maps->nr_ids)) 2749 continue; 2750 2751 active |= remove_xps_queue(dev_maps, 2752 copy ? old_dev_maps : NULL, 2753 tci, index); 2754 } 2755 } 2756 2757 if (old_dev_maps) 2758 kfree_rcu(old_dev_maps, rcu); 2759 2760 /* free map if not active */ 2761 if (!active) 2762 reset_xps_maps(dev, dev_maps, type); 2763 2764 out_no_maps: 2765 mutex_unlock(&xps_map_mutex); 2766 2767 return 0; 2768 error: 2769 /* remove any maps that we added */ 2770 for (j = 0; j < nr_ids; j++) { 2771 for (i = num_tc, tci = j * num_tc; i--; tci++) { 2772 new_map = xmap_dereference(new_dev_maps->attr_map[tci]); 2773 map = copy ? 2774 xmap_dereference(dev_maps->attr_map[tci]) : 2775 NULL; 2776 if (new_map && new_map != map) 2777 kfree(new_map); 2778 } 2779 } 2780 2781 mutex_unlock(&xps_map_mutex); 2782 2783 kfree(new_dev_maps); 2784 return -ENOMEM; 2785 } 2786 EXPORT_SYMBOL_GPL(__netif_set_xps_queue); 2787 2788 int netif_set_xps_queue(struct net_device *dev, const struct cpumask *mask, 2789 u16 index) 2790 { 2791 int ret; 2792 2793 cpus_read_lock(); 2794 ret = __netif_set_xps_queue(dev, cpumask_bits(mask), index, XPS_CPUS); 2795 cpus_read_unlock(); 2796 2797 return ret; 2798 } 2799 EXPORT_SYMBOL(netif_set_xps_queue); 2800 2801 #endif 2802 static void netdev_unbind_all_sb_channels(struct net_device *dev) 2803 { 2804 struct netdev_queue *txq = &dev->_tx[dev->num_tx_queues]; 2805 2806 /* Unbind any subordinate channels */ 2807 while (txq-- != &dev->_tx[0]) { 2808 if (txq->sb_dev) 2809 netdev_unbind_sb_channel(dev, txq->sb_dev); 2810 } 2811 } 2812 2813 void netdev_reset_tc(struct net_device *dev) 2814 { 2815 #ifdef CONFIG_XPS 2816 netif_reset_xps_queues_gt(dev, 0); 2817 #endif 2818 netdev_unbind_all_sb_channels(dev); 2819 2820 /* Reset TC configuration of device */ 2821 dev->num_tc = 0; 2822 memset(dev->tc_to_txq, 0, sizeof(dev->tc_to_txq)); 2823 memset(dev->prio_tc_map, 0, sizeof(dev->prio_tc_map)); 2824 } 2825 EXPORT_SYMBOL(netdev_reset_tc); 2826 2827 int netdev_set_tc_queue(struct net_device *dev, u8 tc, u16 count, u16 offset) 2828 { 2829 if (tc >= dev->num_tc) 2830 return -EINVAL; 2831 2832 #ifdef CONFIG_XPS 2833 netif_reset_xps_queues(dev, offset, count); 2834 #endif 2835 dev->tc_to_txq[tc].count = count; 2836 dev->tc_to_txq[tc].offset = offset; 2837 return 0; 2838 } 2839 EXPORT_SYMBOL(netdev_set_tc_queue); 2840 2841 int netdev_set_num_tc(struct net_device *dev, u8 num_tc) 2842 { 2843 if (num_tc > TC_MAX_QUEUE) 2844 return -EINVAL; 2845 2846 #ifdef CONFIG_XPS 2847 netif_reset_xps_queues_gt(dev, 0); 2848 #endif 2849 netdev_unbind_all_sb_channels(dev); 2850 2851 dev->num_tc = num_tc; 2852 return 0; 2853 } 2854 EXPORT_SYMBOL(netdev_set_num_tc); 2855 2856 void netdev_unbind_sb_channel(struct net_device *dev, 2857 struct net_device *sb_dev) 2858 { 2859 struct netdev_queue *txq = &dev->_tx[dev->num_tx_queues]; 2860 2861 #ifdef CONFIG_XPS 2862 netif_reset_xps_queues_gt(sb_dev, 0); 2863 #endif 2864 memset(sb_dev->tc_to_txq, 0, sizeof(sb_dev->tc_to_txq)); 2865 memset(sb_dev->prio_tc_map, 0, sizeof(sb_dev->prio_tc_map)); 2866 2867 while (txq-- != &dev->_tx[0]) { 2868 if (txq->sb_dev == sb_dev) 2869 txq->sb_dev = NULL; 2870 } 2871 } 2872 EXPORT_SYMBOL(netdev_unbind_sb_channel); 2873 2874 int netdev_bind_sb_channel_queue(struct net_device *dev, 2875 struct net_device *sb_dev, 2876 u8 tc, u16 count, u16 offset) 2877 { 2878 /* Make certain the sb_dev and dev are already configured */ 2879 if (sb_dev->num_tc >= 0 || tc >= dev->num_tc) 2880 return -EINVAL; 2881 2882 /* We cannot hand out queues we don't have */ 2883 if ((offset + count) > dev->real_num_tx_queues) 2884 return -EINVAL; 2885 2886 /* Record the mapping */ 2887 sb_dev->tc_to_txq[tc].count = count; 2888 sb_dev->tc_to_txq[tc].offset = offset; 2889 2890 /* Provide a way for Tx queue to find the tc_to_txq map or 2891 * XPS map for itself. 2892 */ 2893 while (count--) 2894 netdev_get_tx_queue(dev, count + offset)->sb_dev = sb_dev; 2895 2896 return 0; 2897 } 2898 EXPORT_SYMBOL(netdev_bind_sb_channel_queue); 2899 2900 int netdev_set_sb_channel(struct net_device *dev, u16 channel) 2901 { 2902 /* Do not use a multiqueue device to represent a subordinate channel */ 2903 if (netif_is_multiqueue(dev)) 2904 return -ENODEV; 2905 2906 /* We allow channels 1 - 32767 to be used for subordinate channels. 2907 * Channel 0 is meant to be "native" mode and used only to represent 2908 * the main root device. We allow writing 0 to reset the device back 2909 * to normal mode after being used as a subordinate channel. 2910 */ 2911 if (channel > S16_MAX) 2912 return -EINVAL; 2913 2914 dev->num_tc = -channel; 2915 2916 return 0; 2917 } 2918 EXPORT_SYMBOL(netdev_set_sb_channel); 2919 2920 /* 2921 * Routine to help set real_num_tx_queues. To avoid skbs mapped to queues 2922 * greater than real_num_tx_queues stale skbs on the qdisc must be flushed. 2923 */ 2924 int netif_set_real_num_tx_queues(struct net_device *dev, unsigned int txq) 2925 { 2926 bool disabling; 2927 int rc; 2928 2929 disabling = txq < dev->real_num_tx_queues; 2930 2931 if (txq < 1 || txq > dev->num_tx_queues) 2932 return -EINVAL; 2933 2934 if (dev->reg_state == NETREG_REGISTERED || 2935 dev->reg_state == NETREG_UNREGISTERING) { 2936 ASSERT_RTNL(); 2937 2938 rc = netdev_queue_update_kobjects(dev, dev->real_num_tx_queues, 2939 txq); 2940 if (rc) 2941 return rc; 2942 2943 if (dev->num_tc) 2944 netif_setup_tc(dev, txq); 2945 2946 dev_qdisc_change_real_num_tx(dev, txq); 2947 2948 dev->real_num_tx_queues = txq; 2949 2950 if (disabling) { 2951 synchronize_net(); 2952 qdisc_reset_all_tx_gt(dev, txq); 2953 #ifdef CONFIG_XPS 2954 netif_reset_xps_queues_gt(dev, txq); 2955 #endif 2956 } 2957 } else { 2958 dev->real_num_tx_queues = txq; 2959 } 2960 2961 return 0; 2962 } 2963 EXPORT_SYMBOL(netif_set_real_num_tx_queues); 2964 2965 #ifdef CONFIG_SYSFS 2966 /** 2967 * netif_set_real_num_rx_queues - set actual number of RX queues used 2968 * @dev: Network device 2969 * @rxq: Actual number of RX queues 2970 * 2971 * This must be called either with the rtnl_lock held or before 2972 * registration of the net device. Returns 0 on success, or a 2973 * negative error code. If called before registration, it always 2974 * succeeds. 2975 */ 2976 int netif_set_real_num_rx_queues(struct net_device *dev, unsigned int rxq) 2977 { 2978 int rc; 2979 2980 if (rxq < 1 || rxq > dev->num_rx_queues) 2981 return -EINVAL; 2982 2983 if (dev->reg_state == NETREG_REGISTERED) { 2984 ASSERT_RTNL(); 2985 2986 rc = net_rx_queue_update_kobjects(dev, dev->real_num_rx_queues, 2987 rxq); 2988 if (rc) 2989 return rc; 2990 } 2991 2992 dev->real_num_rx_queues = rxq; 2993 return 0; 2994 } 2995 EXPORT_SYMBOL(netif_set_real_num_rx_queues); 2996 #endif 2997 2998 /** 2999 * netif_set_real_num_queues - set actual number of RX and TX queues used 3000 * @dev: Network device 3001 * @txq: Actual number of TX queues 3002 * @rxq: Actual number of RX queues 3003 * 3004 * Set the real number of both TX and RX queues. 3005 * Does nothing if the number of queues is already correct. 3006 */ 3007 int netif_set_real_num_queues(struct net_device *dev, 3008 unsigned int txq, unsigned int rxq) 3009 { 3010 unsigned int old_rxq = dev->real_num_rx_queues; 3011 int err; 3012 3013 if (txq < 1 || txq > dev->num_tx_queues || 3014 rxq < 1 || rxq > dev->num_rx_queues) 3015 return -EINVAL; 3016 3017 /* Start from increases, so the error path only does decreases - 3018 * decreases can't fail. 3019 */ 3020 if (rxq > dev->real_num_rx_queues) { 3021 err = netif_set_real_num_rx_queues(dev, rxq); 3022 if (err) 3023 return err; 3024 } 3025 if (txq > dev->real_num_tx_queues) { 3026 err = netif_set_real_num_tx_queues(dev, txq); 3027 if (err) 3028 goto undo_rx; 3029 } 3030 if (rxq < dev->real_num_rx_queues) 3031 WARN_ON(netif_set_real_num_rx_queues(dev, rxq)); 3032 if (txq < dev->real_num_tx_queues) 3033 WARN_ON(netif_set_real_num_tx_queues(dev, txq)); 3034 3035 return 0; 3036 undo_rx: 3037 WARN_ON(netif_set_real_num_rx_queues(dev, old_rxq)); 3038 return err; 3039 } 3040 EXPORT_SYMBOL(netif_set_real_num_queues); 3041 3042 /** 3043 * netif_set_tso_max_size() - set the max size of TSO frames supported 3044 * @dev: netdev to update 3045 * @size: max skb->len of a TSO frame 3046 * 3047 * Set the limit on the size of TSO super-frames the device can handle. 3048 * Unless explicitly set the stack will assume the value of 3049 * %GSO_LEGACY_MAX_SIZE. 3050 */ 3051 void netif_set_tso_max_size(struct net_device *dev, unsigned int size) 3052 { 3053 dev->tso_max_size = min(GSO_MAX_SIZE, size); 3054 if (size < READ_ONCE(dev->gso_max_size)) 3055 netif_set_gso_max_size(dev, size); 3056 if (size < READ_ONCE(dev->gso_ipv4_max_size)) 3057 netif_set_gso_ipv4_max_size(dev, size); 3058 } 3059 EXPORT_SYMBOL(netif_set_tso_max_size); 3060 3061 /** 3062 * netif_set_tso_max_segs() - set the max number of segs supported for TSO 3063 * @dev: netdev to update 3064 * @segs: max number of TCP segments 3065 * 3066 * Set the limit on the number of TCP segments the device can generate from 3067 * a single TSO super-frame. 3068 * Unless explicitly set the stack will assume the value of %GSO_MAX_SEGS. 3069 */ 3070 void netif_set_tso_max_segs(struct net_device *dev, unsigned int segs) 3071 { 3072 dev->tso_max_segs = segs; 3073 if (segs < READ_ONCE(dev->gso_max_segs)) 3074 netif_set_gso_max_segs(dev, segs); 3075 } 3076 EXPORT_SYMBOL(netif_set_tso_max_segs); 3077 3078 /** 3079 * netif_inherit_tso_max() - copy all TSO limits from a lower device to an upper 3080 * @to: netdev to update 3081 * @from: netdev from which to copy the limits 3082 */ 3083 void netif_inherit_tso_max(struct net_device *to, const struct net_device *from) 3084 { 3085 netif_set_tso_max_size(to, from->tso_max_size); 3086 netif_set_tso_max_segs(to, from->tso_max_segs); 3087 } 3088 EXPORT_SYMBOL(netif_inherit_tso_max); 3089 3090 /** 3091 * netif_get_num_default_rss_queues - default number of RSS queues 3092 * 3093 * Default value is the number of physical cores if there are only 1 or 2, or 3094 * divided by 2 if there are more. 3095 */ 3096 int netif_get_num_default_rss_queues(void) 3097 { 3098 cpumask_var_t cpus; 3099 int cpu, count = 0; 3100 3101 if (unlikely(is_kdump_kernel() || !zalloc_cpumask_var(&cpus, GFP_KERNEL))) 3102 return 1; 3103 3104 cpumask_copy(cpus, cpu_online_mask); 3105 for_each_cpu(cpu, cpus) { 3106 ++count; 3107 cpumask_andnot(cpus, cpus, topology_sibling_cpumask(cpu)); 3108 } 3109 free_cpumask_var(cpus); 3110 3111 return count > 2 ? DIV_ROUND_UP(count, 2) : count; 3112 } 3113 EXPORT_SYMBOL(netif_get_num_default_rss_queues); 3114 3115 static void __netif_reschedule(struct Qdisc *q) 3116 { 3117 struct softnet_data *sd; 3118 unsigned long flags; 3119 3120 local_irq_save(flags); 3121 sd = this_cpu_ptr(&softnet_data); 3122 q->next_sched = NULL; 3123 *sd->output_queue_tailp = q; 3124 sd->output_queue_tailp = &q->next_sched; 3125 raise_softirq_irqoff(NET_TX_SOFTIRQ); 3126 local_irq_restore(flags); 3127 } 3128 3129 void __netif_schedule(struct Qdisc *q) 3130 { 3131 if (!test_and_set_bit(__QDISC_STATE_SCHED, &q->state)) 3132 __netif_reschedule(q); 3133 } 3134 EXPORT_SYMBOL(__netif_schedule); 3135 3136 struct dev_kfree_skb_cb { 3137 enum skb_drop_reason reason; 3138 }; 3139 3140 static struct dev_kfree_skb_cb *get_kfree_skb_cb(const struct sk_buff *skb) 3141 { 3142 return (struct dev_kfree_skb_cb *)skb->cb; 3143 } 3144 3145 void netif_schedule_queue(struct netdev_queue *txq) 3146 { 3147 rcu_read_lock(); 3148 if (!netif_xmit_stopped(txq)) { 3149 struct Qdisc *q = rcu_dereference(txq->qdisc); 3150 3151 __netif_schedule(q); 3152 } 3153 rcu_read_unlock(); 3154 } 3155 EXPORT_SYMBOL(netif_schedule_queue); 3156 3157 void netif_tx_wake_queue(struct netdev_queue *dev_queue) 3158 { 3159 if (test_and_clear_bit(__QUEUE_STATE_DRV_XOFF, &dev_queue->state)) { 3160 struct Qdisc *q; 3161 3162 rcu_read_lock(); 3163 q = rcu_dereference(dev_queue->qdisc); 3164 __netif_schedule(q); 3165 rcu_read_unlock(); 3166 } 3167 } 3168 EXPORT_SYMBOL(netif_tx_wake_queue); 3169 3170 void dev_kfree_skb_irq_reason(struct sk_buff *skb, enum skb_drop_reason reason) 3171 { 3172 unsigned long flags; 3173 3174 if (unlikely(!skb)) 3175 return; 3176 3177 if (likely(refcount_read(&skb->users) == 1)) { 3178 smp_rmb(); 3179 refcount_set(&skb->users, 0); 3180 } else if (likely(!refcount_dec_and_test(&skb->users))) { 3181 return; 3182 } 3183 get_kfree_skb_cb(skb)->reason = reason; 3184 local_irq_save(flags); 3185 skb->next = __this_cpu_read(softnet_data.completion_queue); 3186 __this_cpu_write(softnet_data.completion_queue, skb); 3187 raise_softirq_irqoff(NET_TX_SOFTIRQ); 3188 local_irq_restore(flags); 3189 } 3190 EXPORT_SYMBOL(dev_kfree_skb_irq_reason); 3191 3192 void dev_kfree_skb_any_reason(struct sk_buff *skb, enum skb_drop_reason reason) 3193 { 3194 if (in_hardirq() || irqs_disabled()) 3195 dev_kfree_skb_irq_reason(skb, reason); 3196 else 3197 kfree_skb_reason(skb, reason); 3198 } 3199 EXPORT_SYMBOL(dev_kfree_skb_any_reason); 3200 3201 3202 /** 3203 * netif_device_detach - mark device as removed 3204 * @dev: network device 3205 * 3206 * Mark device as removed from system and therefore no longer available. 3207 */ 3208 void netif_device_detach(struct net_device *dev) 3209 { 3210 if (test_and_clear_bit(__LINK_STATE_PRESENT, &dev->state) && 3211 netif_running(dev)) { 3212 netif_tx_stop_all_queues(dev); 3213 } 3214 } 3215 EXPORT_SYMBOL(netif_device_detach); 3216 3217 /** 3218 * netif_device_attach - mark device as attached 3219 * @dev: network device 3220 * 3221 * Mark device as attached from system and restart if needed. 3222 */ 3223 void netif_device_attach(struct net_device *dev) 3224 { 3225 if (!test_and_set_bit(__LINK_STATE_PRESENT, &dev->state) && 3226 netif_running(dev)) { 3227 netif_tx_wake_all_queues(dev); 3228 __netdev_watchdog_up(dev); 3229 } 3230 } 3231 EXPORT_SYMBOL(netif_device_attach); 3232 3233 /* 3234 * Returns a Tx hash based on the given packet descriptor a Tx queues' number 3235 * to be used as a distribution range. 3236 */ 3237 static u16 skb_tx_hash(const struct net_device *dev, 3238 const struct net_device *sb_dev, 3239 struct sk_buff *skb) 3240 { 3241 u32 hash; 3242 u16 qoffset = 0; 3243 u16 qcount = dev->real_num_tx_queues; 3244 3245 if (dev->num_tc) { 3246 u8 tc = netdev_get_prio_tc_map(dev, skb->priority); 3247 3248 qoffset = sb_dev->tc_to_txq[tc].offset; 3249 qcount = sb_dev->tc_to_txq[tc].count; 3250 if (unlikely(!qcount)) { 3251 net_warn_ratelimited("%s: invalid qcount, qoffset %u for tc %u\n", 3252 sb_dev->name, qoffset, tc); 3253 qoffset = 0; 3254 qcount = dev->real_num_tx_queues; 3255 } 3256 } 3257 3258 if (skb_rx_queue_recorded(skb)) { 3259 DEBUG_NET_WARN_ON_ONCE(qcount == 0); 3260 hash = skb_get_rx_queue(skb); 3261 if (hash >= qoffset) 3262 hash -= qoffset; 3263 while (unlikely(hash >= qcount)) 3264 hash -= qcount; 3265 return hash + qoffset; 3266 } 3267 3268 return (u16) reciprocal_scale(skb_get_hash(skb), qcount) + qoffset; 3269 } 3270 3271 void skb_warn_bad_offload(const struct sk_buff *skb) 3272 { 3273 static const netdev_features_t null_features; 3274 struct net_device *dev = skb->dev; 3275 const char *name = ""; 3276 3277 if (!net_ratelimit()) 3278 return; 3279 3280 if (dev) { 3281 if (dev->dev.parent) 3282 name = dev_driver_string(dev->dev.parent); 3283 else 3284 name = netdev_name(dev); 3285 } 3286 skb_dump(KERN_WARNING, skb, false); 3287 WARN(1, "%s: caps=(%pNF, %pNF)\n", 3288 name, dev ? &dev->features : &null_features, 3289 skb->sk ? &skb->sk->sk_route_caps : &null_features); 3290 } 3291 3292 /* 3293 * Invalidate hardware checksum when packet is to be mangled, and 3294 * complete checksum manually on outgoing path. 3295 */ 3296 int skb_checksum_help(struct sk_buff *skb) 3297 { 3298 __wsum csum; 3299 int ret = 0, offset; 3300 3301 if (skb->ip_summed == CHECKSUM_COMPLETE) 3302 goto out_set_summed; 3303 3304 if (unlikely(skb_is_gso(skb))) { 3305 skb_warn_bad_offload(skb); 3306 return -EINVAL; 3307 } 3308 3309 /* Before computing a checksum, we should make sure no frag could 3310 * be modified by an external entity : checksum could be wrong. 3311 */ 3312 if (skb_has_shared_frag(skb)) { 3313 ret = __skb_linearize(skb); 3314 if (ret) 3315 goto out; 3316 } 3317 3318 offset = skb_checksum_start_offset(skb); 3319 ret = -EINVAL; 3320 if (unlikely(offset >= skb_headlen(skb))) { 3321 DO_ONCE_LITE(skb_dump, KERN_ERR, skb, false); 3322 WARN_ONCE(true, "offset (%d) >= skb_headlen() (%u)\n", 3323 offset, skb_headlen(skb)); 3324 goto out; 3325 } 3326 csum = skb_checksum(skb, offset, skb->len - offset, 0); 3327 3328 offset += skb->csum_offset; 3329 if (unlikely(offset + sizeof(__sum16) > skb_headlen(skb))) { 3330 DO_ONCE_LITE(skb_dump, KERN_ERR, skb, false); 3331 WARN_ONCE(true, "offset+2 (%zu) > skb_headlen() (%u)\n", 3332 offset + sizeof(__sum16), skb_headlen(skb)); 3333 goto out; 3334 } 3335 ret = skb_ensure_writable(skb, offset + sizeof(__sum16)); 3336 if (ret) 3337 goto out; 3338 3339 *(__sum16 *)(skb->data + offset) = csum_fold(csum) ?: CSUM_MANGLED_0; 3340 out_set_summed: 3341 skb->ip_summed = CHECKSUM_NONE; 3342 out: 3343 return ret; 3344 } 3345 EXPORT_SYMBOL(skb_checksum_help); 3346 3347 int skb_crc32c_csum_help(struct sk_buff *skb) 3348 { 3349 __le32 crc32c_csum; 3350 int ret = 0, offset, start; 3351 3352 if (skb->ip_summed != CHECKSUM_PARTIAL) 3353 goto out; 3354 3355 if (unlikely(skb_is_gso(skb))) 3356 goto out; 3357 3358 /* Before computing a checksum, we should make sure no frag could 3359 * be modified by an external entity : checksum could be wrong. 3360 */ 3361 if (unlikely(skb_has_shared_frag(skb))) { 3362 ret = __skb_linearize(skb); 3363 if (ret) 3364 goto out; 3365 } 3366 start = skb_checksum_start_offset(skb); 3367 offset = start + offsetof(struct sctphdr, checksum); 3368 if (WARN_ON_ONCE(offset >= skb_headlen(skb))) { 3369 ret = -EINVAL; 3370 goto out; 3371 } 3372 3373 ret = skb_ensure_writable(skb, offset + sizeof(__le32)); 3374 if (ret) 3375 goto out; 3376 3377 crc32c_csum = cpu_to_le32(~__skb_checksum(skb, start, 3378 skb->len - start, ~(__u32)0, 3379 crc32c_csum_stub)); 3380 *(__le32 *)(skb->data + offset) = crc32c_csum; 3381 skb_reset_csum_not_inet(skb); 3382 out: 3383 return ret; 3384 } 3385 3386 __be16 skb_network_protocol(struct sk_buff *skb, int *depth) 3387 { 3388 __be16 type = skb->protocol; 3389 3390 /* Tunnel gso handlers can set protocol to ethernet. */ 3391 if (type == htons(ETH_P_TEB)) { 3392 struct ethhdr *eth; 3393 3394 if (unlikely(!pskb_may_pull(skb, sizeof(struct ethhdr)))) 3395 return 0; 3396 3397 eth = (struct ethhdr *)skb->data; 3398 type = eth->h_proto; 3399 } 3400 3401 return vlan_get_protocol_and_depth(skb, type, depth); 3402 } 3403 3404 3405 /* Take action when hardware reception checksum errors are detected. */ 3406 #ifdef CONFIG_BUG 3407 static void do_netdev_rx_csum_fault(struct net_device *dev, struct sk_buff *skb) 3408 { 3409 netdev_err(dev, "hw csum failure\n"); 3410 skb_dump(KERN_ERR, skb, true); 3411 dump_stack(); 3412 } 3413 3414 void netdev_rx_csum_fault(struct net_device *dev, struct sk_buff *skb) 3415 { 3416 DO_ONCE_LITE(do_netdev_rx_csum_fault, dev, skb); 3417 } 3418 EXPORT_SYMBOL(netdev_rx_csum_fault); 3419 #endif 3420 3421 /* XXX: check that highmem exists at all on the given machine. */ 3422 static int illegal_highdma(struct net_device *dev, struct sk_buff *skb) 3423 { 3424 #ifdef CONFIG_HIGHMEM 3425 int i; 3426 3427 if (!(dev->features & NETIF_F_HIGHDMA)) { 3428 for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) { 3429 skb_frag_t *frag = &skb_shinfo(skb)->frags[i]; 3430 3431 if (PageHighMem(skb_frag_page(frag))) 3432 return 1; 3433 } 3434 } 3435 #endif 3436 return 0; 3437 } 3438 3439 /* If MPLS offload request, verify we are testing hardware MPLS features 3440 * instead of standard features for the netdev. 3441 */ 3442 #if IS_ENABLED(CONFIG_NET_MPLS_GSO) 3443 static netdev_features_t net_mpls_features(struct sk_buff *skb, 3444 netdev_features_t features, 3445 __be16 type) 3446 { 3447 if (eth_p_mpls(type)) 3448 features &= skb->dev->mpls_features; 3449 3450 return features; 3451 } 3452 #else 3453 static netdev_features_t net_mpls_features(struct sk_buff *skb, 3454 netdev_features_t features, 3455 __be16 type) 3456 { 3457 return features; 3458 } 3459 #endif 3460 3461 static netdev_features_t harmonize_features(struct sk_buff *skb, 3462 netdev_features_t features) 3463 { 3464 __be16 type; 3465 3466 type = skb_network_protocol(skb, NULL); 3467 features = net_mpls_features(skb, features, type); 3468 3469 if (skb->ip_summed != CHECKSUM_NONE && 3470 !can_checksum_protocol(features, type)) { 3471 features &= ~(NETIF_F_CSUM_MASK | NETIF_F_GSO_MASK); 3472 } 3473 if (illegal_highdma(skb->dev, skb)) 3474 features &= ~NETIF_F_SG; 3475 3476 return features; 3477 } 3478 3479 netdev_features_t passthru_features_check(struct sk_buff *skb, 3480 struct net_device *dev, 3481 netdev_features_t features) 3482 { 3483 return features; 3484 } 3485 EXPORT_SYMBOL(passthru_features_check); 3486 3487 static netdev_features_t dflt_features_check(struct sk_buff *skb, 3488 struct net_device *dev, 3489 netdev_features_t features) 3490 { 3491 return vlan_features_check(skb, features); 3492 } 3493 3494 static netdev_features_t gso_features_check(const struct sk_buff *skb, 3495 struct net_device *dev, 3496 netdev_features_t features) 3497 { 3498 u16 gso_segs = skb_shinfo(skb)->gso_segs; 3499 3500 if (gso_segs > READ_ONCE(dev->gso_max_segs)) 3501 return features & ~NETIF_F_GSO_MASK; 3502 3503 if (unlikely(skb->len >= netif_get_gso_max_size(dev, skb))) 3504 return features & ~NETIF_F_GSO_MASK; 3505 3506 if (!skb_shinfo(skb)->gso_type) { 3507 skb_warn_bad_offload(skb); 3508 return features & ~NETIF_F_GSO_MASK; 3509 } 3510 3511 /* Support for GSO partial features requires software 3512 * intervention before we can actually process the packets 3513 * so we need to strip support for any partial features now 3514 * and we can pull them back in after we have partially 3515 * segmented the frame. 3516 */ 3517 if (!(skb_shinfo(skb)->gso_type & SKB_GSO_PARTIAL)) 3518 features &= ~dev->gso_partial_features; 3519 3520 /* Make sure to clear the IPv4 ID mangling feature if the 3521 * IPv4 header has the potential to be fragmented. 3522 */ 3523 if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV4) { 3524 struct iphdr *iph = skb->encapsulation ? 3525 inner_ip_hdr(skb) : ip_hdr(skb); 3526 3527 if (!(iph->frag_off & htons(IP_DF))) 3528 features &= ~NETIF_F_TSO_MANGLEID; 3529 } 3530 3531 return features; 3532 } 3533 3534 netdev_features_t netif_skb_features(struct sk_buff *skb) 3535 { 3536 struct net_device *dev = skb->dev; 3537 netdev_features_t features = dev->features; 3538 3539 if (skb_is_gso(skb)) 3540 features = gso_features_check(skb, dev, features); 3541 3542 /* If encapsulation offload request, verify we are testing 3543 * hardware encapsulation features instead of standard 3544 * features for the netdev 3545 */ 3546 if (skb->encapsulation) 3547 features &= dev->hw_enc_features; 3548 3549 if (skb_vlan_tagged(skb)) 3550 features = netdev_intersect_features(features, 3551 dev->vlan_features | 3552 NETIF_F_HW_VLAN_CTAG_TX | 3553 NETIF_F_HW_VLAN_STAG_TX); 3554 3555 if (dev->netdev_ops->ndo_features_check) 3556 features &= dev->netdev_ops->ndo_features_check(skb, dev, 3557 features); 3558 else 3559 features &= dflt_features_check(skb, dev, features); 3560 3561 return harmonize_features(skb, features); 3562 } 3563 EXPORT_SYMBOL(netif_skb_features); 3564 3565 static int xmit_one(struct sk_buff *skb, struct net_device *dev, 3566 struct netdev_queue *txq, bool more) 3567 { 3568 unsigned int len; 3569 int rc; 3570 3571 if (dev_nit_active(dev)) 3572 dev_queue_xmit_nit(skb, dev); 3573 3574 len = skb->len; 3575 trace_net_dev_start_xmit(skb, dev); 3576 rc = netdev_start_xmit(skb, dev, txq, more); 3577 trace_net_dev_xmit(skb, rc, dev, len); 3578 3579 return rc; 3580 } 3581 3582 struct sk_buff *dev_hard_start_xmit(struct sk_buff *first, struct net_device *dev, 3583 struct netdev_queue *txq, int *ret) 3584 { 3585 struct sk_buff *skb = first; 3586 int rc = NETDEV_TX_OK; 3587 3588 while (skb) { 3589 struct sk_buff *next = skb->next; 3590 3591 skb_mark_not_on_list(skb); 3592 rc = xmit_one(skb, dev, txq, next != NULL); 3593 if (unlikely(!dev_xmit_complete(rc))) { 3594 skb->next = next; 3595 goto out; 3596 } 3597 3598 skb = next; 3599 if (netif_tx_queue_stopped(txq) && skb) { 3600 rc = NETDEV_TX_BUSY; 3601 break; 3602 } 3603 } 3604 3605 out: 3606 *ret = rc; 3607 return skb; 3608 } 3609 3610 static struct sk_buff *validate_xmit_vlan(struct sk_buff *skb, 3611 netdev_features_t features) 3612 { 3613 if (skb_vlan_tag_present(skb) && 3614 !vlan_hw_offload_capable(features, skb->vlan_proto)) 3615 skb = __vlan_hwaccel_push_inside(skb); 3616 return skb; 3617 } 3618 3619 int skb_csum_hwoffload_help(struct sk_buff *skb, 3620 const netdev_features_t features) 3621 { 3622 if (unlikely(skb_csum_is_sctp(skb))) 3623 return !!(features & NETIF_F_SCTP_CRC) ? 0 : 3624 skb_crc32c_csum_help(skb); 3625 3626 if (features & NETIF_F_HW_CSUM) 3627 return 0; 3628 3629 if (features & (NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM)) { 3630 switch (skb->csum_offset) { 3631 case offsetof(struct tcphdr, check): 3632 case offsetof(struct udphdr, check): 3633 return 0; 3634 } 3635 } 3636 3637 return skb_checksum_help(skb); 3638 } 3639 EXPORT_SYMBOL(skb_csum_hwoffload_help); 3640 3641 static struct sk_buff *validate_xmit_skb(struct sk_buff *skb, struct net_device *dev, bool *again) 3642 { 3643 netdev_features_t features; 3644 3645 features = netif_skb_features(skb); 3646 skb = validate_xmit_vlan(skb, features); 3647 if (unlikely(!skb)) 3648 goto out_null; 3649 3650 skb = sk_validate_xmit_skb(skb, dev); 3651 if (unlikely(!skb)) 3652 goto out_null; 3653 3654 if (netif_needs_gso(skb, features)) { 3655 struct sk_buff *segs; 3656 3657 segs = skb_gso_segment(skb, features); 3658 if (IS_ERR(segs)) { 3659 goto out_kfree_skb; 3660 } else if (segs) { 3661 consume_skb(skb); 3662 skb = segs; 3663 } 3664 } else { 3665 if (skb_needs_linearize(skb, features) && 3666 __skb_linearize(skb)) 3667 goto out_kfree_skb; 3668 3669 /* If packet is not checksummed and device does not 3670 * support checksumming for this protocol, complete 3671 * checksumming here. 3672 */ 3673 if (skb->ip_summed == CHECKSUM_PARTIAL) { 3674 if (skb->encapsulation) 3675 skb_set_inner_transport_header(skb, 3676 skb_checksum_start_offset(skb)); 3677 else 3678 skb_set_transport_header(skb, 3679 skb_checksum_start_offset(skb)); 3680 if (skb_csum_hwoffload_help(skb, features)) 3681 goto out_kfree_skb; 3682 } 3683 } 3684 3685 skb = validate_xmit_xfrm(skb, features, again); 3686 3687 return skb; 3688 3689 out_kfree_skb: 3690 kfree_skb(skb); 3691 out_null: 3692 dev_core_stats_tx_dropped_inc(dev); 3693 return NULL; 3694 } 3695 3696 struct sk_buff *validate_xmit_skb_list(struct sk_buff *skb, struct net_device *dev, bool *again) 3697 { 3698 struct sk_buff *next, *head = NULL, *tail; 3699 3700 for (; skb != NULL; skb = next) { 3701 next = skb->next; 3702 skb_mark_not_on_list(skb); 3703 3704 /* in case skb wont be segmented, point to itself */ 3705 skb->prev = skb; 3706 3707 skb = validate_xmit_skb(skb, dev, again); 3708 if (!skb) 3709 continue; 3710 3711 if (!head) 3712 head = skb; 3713 else 3714 tail->next = skb; 3715 /* If skb was segmented, skb->prev points to 3716 * the last segment. If not, it still contains skb. 3717 */ 3718 tail = skb->prev; 3719 } 3720 return head; 3721 } 3722 EXPORT_SYMBOL_GPL(validate_xmit_skb_list); 3723 3724 static void qdisc_pkt_len_init(struct sk_buff *skb) 3725 { 3726 const struct skb_shared_info *shinfo = skb_shinfo(skb); 3727 3728 qdisc_skb_cb(skb)->pkt_len = skb->len; 3729 3730 /* To get more precise estimation of bytes sent on wire, 3731 * we add to pkt_len the headers size of all segments 3732 */ 3733 if (shinfo->gso_size && skb_transport_header_was_set(skb)) { 3734 u16 gso_segs = shinfo->gso_segs; 3735 unsigned int hdr_len; 3736 3737 /* mac layer + network layer */ 3738 hdr_len = skb_transport_offset(skb); 3739 3740 /* + transport layer */ 3741 if (likely(shinfo->gso_type & (SKB_GSO_TCPV4 | SKB_GSO_TCPV6))) { 3742 const struct tcphdr *th; 3743 struct tcphdr _tcphdr; 3744 3745 th = skb_header_pointer(skb, hdr_len, 3746 sizeof(_tcphdr), &_tcphdr); 3747 if (likely(th)) 3748 hdr_len += __tcp_hdrlen(th); 3749 } else if (shinfo->gso_type & SKB_GSO_UDP_L4) { 3750 struct udphdr _udphdr; 3751 3752 if (skb_header_pointer(skb, hdr_len, 3753 sizeof(_udphdr), &_udphdr)) 3754 hdr_len += sizeof(struct udphdr); 3755 } 3756 3757 if (unlikely(shinfo->gso_type & SKB_GSO_DODGY)) { 3758 int payload = skb->len - hdr_len; 3759 3760 /* Malicious packet. */ 3761 if (payload <= 0) 3762 return; 3763 gso_segs = DIV_ROUND_UP(payload, shinfo->gso_size); 3764 } 3765 qdisc_skb_cb(skb)->pkt_len += (gso_segs - 1) * hdr_len; 3766 } 3767 } 3768 3769 static int dev_qdisc_enqueue(struct sk_buff *skb, struct Qdisc *q, 3770 struct sk_buff **to_free, 3771 struct netdev_queue *txq) 3772 { 3773 int rc; 3774 3775 rc = q->enqueue(skb, q, to_free) & NET_XMIT_MASK; 3776 if (rc == NET_XMIT_SUCCESS) 3777 trace_qdisc_enqueue(q, txq, skb); 3778 return rc; 3779 } 3780 3781 static inline int __dev_xmit_skb(struct sk_buff *skb, struct Qdisc *q, 3782 struct net_device *dev, 3783 struct netdev_queue *txq) 3784 { 3785 spinlock_t *root_lock = qdisc_lock(q); 3786 struct sk_buff *to_free = NULL; 3787 bool contended; 3788 int rc; 3789 3790 qdisc_calculate_pkt_len(skb, q); 3791 3792 if (q->flags & TCQ_F_NOLOCK) { 3793 if (q->flags & TCQ_F_CAN_BYPASS && nolock_qdisc_is_empty(q) && 3794 qdisc_run_begin(q)) { 3795 /* Retest nolock_qdisc_is_empty() within the protection 3796 * of q->seqlock to protect from racing with requeuing. 3797 */ 3798 if (unlikely(!nolock_qdisc_is_empty(q))) { 3799 rc = dev_qdisc_enqueue(skb, q, &to_free, txq); 3800 __qdisc_run(q); 3801 qdisc_run_end(q); 3802 3803 goto no_lock_out; 3804 } 3805 3806 qdisc_bstats_cpu_update(q, skb); 3807 if (sch_direct_xmit(skb, q, dev, txq, NULL, true) && 3808 !nolock_qdisc_is_empty(q)) 3809 __qdisc_run(q); 3810 3811 qdisc_run_end(q); 3812 return NET_XMIT_SUCCESS; 3813 } 3814 3815 rc = dev_qdisc_enqueue(skb, q, &to_free, txq); 3816 qdisc_run(q); 3817 3818 no_lock_out: 3819 if (unlikely(to_free)) 3820 kfree_skb_list_reason(to_free, 3821 SKB_DROP_REASON_QDISC_DROP); 3822 return rc; 3823 } 3824 3825 /* 3826 * Heuristic to force contended enqueues to serialize on a 3827 * separate lock before trying to get qdisc main lock. 3828 * This permits qdisc->running owner to get the lock more 3829 * often and dequeue packets faster. 3830 * On PREEMPT_RT it is possible to preempt the qdisc owner during xmit 3831 * and then other tasks will only enqueue packets. The packets will be 3832 * sent after the qdisc owner is scheduled again. To prevent this 3833 * scenario the task always serialize on the lock. 3834 */ 3835 contended = qdisc_is_running(q) || IS_ENABLED(CONFIG_PREEMPT_RT); 3836 if (unlikely(contended)) 3837 spin_lock(&q->busylock); 3838 3839 spin_lock(root_lock); 3840 if (unlikely(test_bit(__QDISC_STATE_DEACTIVATED, &q->state))) { 3841 __qdisc_drop(skb, &to_free); 3842 rc = NET_XMIT_DROP; 3843 } else if ((q->flags & TCQ_F_CAN_BYPASS) && !qdisc_qlen(q) && 3844 qdisc_run_begin(q)) { 3845 /* 3846 * This is a work-conserving queue; there are no old skbs 3847 * waiting to be sent out; and the qdisc is not running - 3848 * xmit the skb directly. 3849 */ 3850 3851 qdisc_bstats_update(q, skb); 3852 3853 if (sch_direct_xmit(skb, q, dev, txq, root_lock, true)) { 3854 if (unlikely(contended)) { 3855 spin_unlock(&q->busylock); 3856 contended = false; 3857 } 3858 __qdisc_run(q); 3859 } 3860 3861 qdisc_run_end(q); 3862 rc = NET_XMIT_SUCCESS; 3863 } else { 3864 rc = dev_qdisc_enqueue(skb, q, &to_free, txq); 3865 if (qdisc_run_begin(q)) { 3866 if (unlikely(contended)) { 3867 spin_unlock(&q->busylock); 3868 contended = false; 3869 } 3870 __qdisc_run(q); 3871 qdisc_run_end(q); 3872 } 3873 } 3874 spin_unlock(root_lock); 3875 if (unlikely(to_free)) 3876 kfree_skb_list_reason(to_free, SKB_DROP_REASON_QDISC_DROP); 3877 if (unlikely(contended)) 3878 spin_unlock(&q->busylock); 3879 return rc; 3880 } 3881 3882 #if IS_ENABLED(CONFIG_CGROUP_NET_PRIO) 3883 static void skb_update_prio(struct sk_buff *skb) 3884 { 3885 const struct netprio_map *map; 3886 const struct sock *sk; 3887 unsigned int prioidx; 3888 3889 if (skb->priority) 3890 return; 3891 map = rcu_dereference_bh(skb->dev->priomap); 3892 if (!map) 3893 return; 3894 sk = skb_to_full_sk(skb); 3895 if (!sk) 3896 return; 3897 3898 prioidx = sock_cgroup_prioidx(&sk->sk_cgrp_data); 3899 3900 if (prioidx < map->priomap_len) 3901 skb->priority = map->priomap[prioidx]; 3902 } 3903 #else 3904 #define skb_update_prio(skb) 3905 #endif 3906 3907 /** 3908 * dev_loopback_xmit - loop back @skb 3909 * @net: network namespace this loopback is happening in 3910 * @sk: sk needed to be a netfilter okfn 3911 * @skb: buffer to transmit 3912 */ 3913 int dev_loopback_xmit(struct net *net, struct sock *sk, struct sk_buff *skb) 3914 { 3915 skb_reset_mac_header(skb); 3916 __skb_pull(skb, skb_network_offset(skb)); 3917 skb->pkt_type = PACKET_LOOPBACK; 3918 if (skb->ip_summed == CHECKSUM_NONE) 3919 skb->ip_summed = CHECKSUM_UNNECESSARY; 3920 DEBUG_NET_WARN_ON_ONCE(!skb_dst(skb)); 3921 skb_dst_force(skb); 3922 netif_rx(skb); 3923 return 0; 3924 } 3925 EXPORT_SYMBOL(dev_loopback_xmit); 3926 3927 #ifdef CONFIG_NET_EGRESS 3928 static struct netdev_queue * 3929 netdev_tx_queue_mapping(struct net_device *dev, struct sk_buff *skb) 3930 { 3931 int qm = skb_get_queue_mapping(skb); 3932 3933 return netdev_get_tx_queue(dev, netdev_cap_txqueue(dev, qm)); 3934 } 3935 3936 static bool netdev_xmit_txqueue_skipped(void) 3937 { 3938 return __this_cpu_read(softnet_data.xmit.skip_txqueue); 3939 } 3940 3941 void netdev_xmit_skip_txqueue(bool skip) 3942 { 3943 __this_cpu_write(softnet_data.xmit.skip_txqueue, skip); 3944 } 3945 EXPORT_SYMBOL_GPL(netdev_xmit_skip_txqueue); 3946 #endif /* CONFIG_NET_EGRESS */ 3947 3948 #ifdef CONFIG_NET_XGRESS 3949 static int tc_run(struct tcx_entry *entry, struct sk_buff *skb) 3950 { 3951 int ret = TC_ACT_UNSPEC; 3952 #ifdef CONFIG_NET_CLS_ACT 3953 struct mini_Qdisc *miniq = rcu_dereference_bh(entry->miniq); 3954 struct tcf_result res; 3955 3956 if (!miniq) 3957 return ret; 3958 3959 tc_skb_cb(skb)->mru = 0; 3960 tc_skb_cb(skb)->post_ct = false; 3961 3962 mini_qdisc_bstats_cpu_update(miniq, skb); 3963 ret = tcf_classify(skb, miniq->block, miniq->filter_list, &res, false); 3964 /* Only tcf related quirks below. */ 3965 switch (ret) { 3966 case TC_ACT_SHOT: 3967 mini_qdisc_qstats_cpu_drop(miniq); 3968 break; 3969 case TC_ACT_OK: 3970 case TC_ACT_RECLASSIFY: 3971 skb->tc_index = TC_H_MIN(res.classid); 3972 break; 3973 } 3974 #endif /* CONFIG_NET_CLS_ACT */ 3975 return ret; 3976 } 3977 3978 static DEFINE_STATIC_KEY_FALSE(tcx_needed_key); 3979 3980 void tcx_inc(void) 3981 { 3982 static_branch_inc(&tcx_needed_key); 3983 } 3984 3985 void tcx_dec(void) 3986 { 3987 static_branch_dec(&tcx_needed_key); 3988 } 3989 3990 static __always_inline enum tcx_action_base 3991 tcx_run(const struct bpf_mprog_entry *entry, struct sk_buff *skb, 3992 const bool needs_mac) 3993 { 3994 const struct bpf_mprog_fp *fp; 3995 const struct bpf_prog *prog; 3996 int ret = TCX_NEXT; 3997 3998 if (needs_mac) 3999 __skb_push(skb, skb->mac_len); 4000 bpf_mprog_foreach_prog(entry, fp, prog) { 4001 bpf_compute_data_pointers(skb); 4002 ret = bpf_prog_run(prog, skb); 4003 if (ret != TCX_NEXT) 4004 break; 4005 } 4006 if (needs_mac) 4007 __skb_pull(skb, skb->mac_len); 4008 return tcx_action_code(skb, ret); 4009 } 4010 4011 static __always_inline struct sk_buff * 4012 sch_handle_ingress(struct sk_buff *skb, struct packet_type **pt_prev, int *ret, 4013 struct net_device *orig_dev, bool *another) 4014 { 4015 struct bpf_mprog_entry *entry = rcu_dereference_bh(skb->dev->tcx_ingress); 4016 int sch_ret; 4017 4018 if (!entry) 4019 return skb; 4020 if (*pt_prev) { 4021 *ret = deliver_skb(skb, *pt_prev, orig_dev); 4022 *pt_prev = NULL; 4023 } 4024 4025 qdisc_skb_cb(skb)->pkt_len = skb->len; 4026 tcx_set_ingress(skb, true); 4027 4028 if (static_branch_unlikely(&tcx_needed_key)) { 4029 sch_ret = tcx_run(entry, skb, true); 4030 if (sch_ret != TC_ACT_UNSPEC) 4031 goto ingress_verdict; 4032 } 4033 sch_ret = tc_run(tcx_entry(entry), skb); 4034 ingress_verdict: 4035 switch (sch_ret) { 4036 case TC_ACT_REDIRECT: 4037 /* skb_mac_header check was done by BPF, so we can safely 4038 * push the L2 header back before redirecting to another 4039 * netdev. 4040 */ 4041 __skb_push(skb, skb->mac_len); 4042 if (skb_do_redirect(skb) == -EAGAIN) { 4043 __skb_pull(skb, skb->mac_len); 4044 *another = true; 4045 break; 4046 } 4047 *ret = NET_RX_SUCCESS; 4048 return NULL; 4049 case TC_ACT_SHOT: 4050 kfree_skb_reason(skb, SKB_DROP_REASON_TC_INGRESS); 4051 *ret = NET_RX_DROP; 4052 return NULL; 4053 /* used by tc_run */ 4054 case TC_ACT_STOLEN: 4055 case TC_ACT_QUEUED: 4056 case TC_ACT_TRAP: 4057 consume_skb(skb); 4058 fallthrough; 4059 case TC_ACT_CONSUMED: 4060 *ret = NET_RX_SUCCESS; 4061 return NULL; 4062 } 4063 4064 return skb; 4065 } 4066 4067 static __always_inline struct sk_buff * 4068 sch_handle_egress(struct sk_buff *skb, int *ret, struct net_device *dev) 4069 { 4070 struct bpf_mprog_entry *entry = rcu_dereference_bh(dev->tcx_egress); 4071 int sch_ret; 4072 4073 if (!entry) 4074 return skb; 4075 4076 /* qdisc_skb_cb(skb)->pkt_len & tcx_set_ingress() was 4077 * already set by the caller. 4078 */ 4079 if (static_branch_unlikely(&tcx_needed_key)) { 4080 sch_ret = tcx_run(entry, skb, false); 4081 if (sch_ret != TC_ACT_UNSPEC) 4082 goto egress_verdict; 4083 } 4084 sch_ret = tc_run(tcx_entry(entry), skb); 4085 egress_verdict: 4086 switch (sch_ret) { 4087 case TC_ACT_REDIRECT: 4088 /* No need to push/pop skb's mac_header here on egress! */ 4089 skb_do_redirect(skb); 4090 *ret = NET_XMIT_SUCCESS; 4091 return NULL; 4092 case TC_ACT_SHOT: 4093 kfree_skb_reason(skb, SKB_DROP_REASON_TC_EGRESS); 4094 *ret = NET_XMIT_DROP; 4095 return NULL; 4096 /* used by tc_run */ 4097 case TC_ACT_STOLEN: 4098 case TC_ACT_QUEUED: 4099 case TC_ACT_TRAP: 4100 consume_skb(skb); 4101 fallthrough; 4102 case TC_ACT_CONSUMED: 4103 *ret = NET_XMIT_SUCCESS; 4104 return NULL; 4105 } 4106 4107 return skb; 4108 } 4109 #else 4110 static __always_inline struct sk_buff * 4111 sch_handle_ingress(struct sk_buff *skb, struct packet_type **pt_prev, int *ret, 4112 struct net_device *orig_dev, bool *another) 4113 { 4114 return skb; 4115 } 4116 4117 static __always_inline struct sk_buff * 4118 sch_handle_egress(struct sk_buff *skb, int *ret, struct net_device *dev) 4119 { 4120 return skb; 4121 } 4122 #endif /* CONFIG_NET_XGRESS */ 4123 4124 #ifdef CONFIG_XPS 4125 static int __get_xps_queue_idx(struct net_device *dev, struct sk_buff *skb, 4126 struct xps_dev_maps *dev_maps, unsigned int tci) 4127 { 4128 int tc = netdev_get_prio_tc_map(dev, skb->priority); 4129 struct xps_map *map; 4130 int queue_index = -1; 4131 4132 if (tc >= dev_maps->num_tc || tci >= dev_maps->nr_ids) 4133 return queue_index; 4134 4135 tci *= dev_maps->num_tc; 4136 tci += tc; 4137 4138 map = rcu_dereference(dev_maps->attr_map[tci]); 4139 if (map) { 4140 if (map->len == 1) 4141 queue_index = map->queues[0]; 4142 else 4143 queue_index = map->queues[reciprocal_scale( 4144 skb_get_hash(skb), map->len)]; 4145 if (unlikely(queue_index >= dev->real_num_tx_queues)) 4146 queue_index = -1; 4147 } 4148 return queue_index; 4149 } 4150 #endif 4151 4152 static int get_xps_queue(struct net_device *dev, struct net_device *sb_dev, 4153 struct sk_buff *skb) 4154 { 4155 #ifdef CONFIG_XPS 4156 struct xps_dev_maps *dev_maps; 4157 struct sock *sk = skb->sk; 4158 int queue_index = -1; 4159 4160 if (!static_key_false(&xps_needed)) 4161 return -1; 4162 4163 rcu_read_lock(); 4164 if (!static_key_false(&xps_rxqs_needed)) 4165 goto get_cpus_map; 4166 4167 dev_maps = rcu_dereference(sb_dev->xps_maps[XPS_RXQS]); 4168 if (dev_maps) { 4169 int tci = sk_rx_queue_get(sk); 4170 4171 if (tci >= 0) 4172 queue_index = __get_xps_queue_idx(dev, skb, dev_maps, 4173 tci); 4174 } 4175 4176 get_cpus_map: 4177 if (queue_index < 0) { 4178 dev_maps = rcu_dereference(sb_dev->xps_maps[XPS_CPUS]); 4179 if (dev_maps) { 4180 unsigned int tci = skb->sender_cpu - 1; 4181 4182 queue_index = __get_xps_queue_idx(dev, skb, dev_maps, 4183 tci); 4184 } 4185 } 4186 rcu_read_unlock(); 4187 4188 return queue_index; 4189 #else 4190 return -1; 4191 #endif 4192 } 4193 4194 u16 dev_pick_tx_zero(struct net_device *dev, struct sk_buff *skb, 4195 struct net_device *sb_dev) 4196 { 4197 return 0; 4198 } 4199 EXPORT_SYMBOL(dev_pick_tx_zero); 4200 4201 u16 dev_pick_tx_cpu_id(struct net_device *dev, struct sk_buff *skb, 4202 struct net_device *sb_dev) 4203 { 4204 return (u16)raw_smp_processor_id() % dev->real_num_tx_queues; 4205 } 4206 EXPORT_SYMBOL(dev_pick_tx_cpu_id); 4207 4208 u16 netdev_pick_tx(struct net_device *dev, struct sk_buff *skb, 4209 struct net_device *sb_dev) 4210 { 4211 struct sock *sk = skb->sk; 4212 int queue_index = sk_tx_queue_get(sk); 4213 4214 sb_dev = sb_dev ? : dev; 4215 4216 if (queue_index < 0 || skb->ooo_okay || 4217 queue_index >= dev->real_num_tx_queues) { 4218 int new_index = get_xps_queue(dev, sb_dev, skb); 4219 4220 if (new_index < 0) 4221 new_index = skb_tx_hash(dev, sb_dev, skb); 4222 4223 if (queue_index != new_index && sk && 4224 sk_fullsock(sk) && 4225 rcu_access_pointer(sk->sk_dst_cache)) 4226 sk_tx_queue_set(sk, new_index); 4227 4228 queue_index = new_index; 4229 } 4230 4231 return queue_index; 4232 } 4233 EXPORT_SYMBOL(netdev_pick_tx); 4234 4235 struct netdev_queue *netdev_core_pick_tx(struct net_device *dev, 4236 struct sk_buff *skb, 4237 struct net_device *sb_dev) 4238 { 4239 int queue_index = 0; 4240 4241 #ifdef CONFIG_XPS 4242 u32 sender_cpu = skb->sender_cpu - 1; 4243 4244 if (sender_cpu >= (u32)NR_CPUS) 4245 skb->sender_cpu = raw_smp_processor_id() + 1; 4246 #endif 4247 4248 if (dev->real_num_tx_queues != 1) { 4249 const struct net_device_ops *ops = dev->netdev_ops; 4250 4251 if (ops->ndo_select_queue) 4252 queue_index = ops->ndo_select_queue(dev, skb, sb_dev); 4253 else 4254 queue_index = netdev_pick_tx(dev, skb, sb_dev); 4255 4256 queue_index = netdev_cap_txqueue(dev, queue_index); 4257 } 4258 4259 skb_set_queue_mapping(skb, queue_index); 4260 return netdev_get_tx_queue(dev, queue_index); 4261 } 4262 4263 /** 4264 * __dev_queue_xmit() - transmit a buffer 4265 * @skb: buffer to transmit 4266 * @sb_dev: suboordinate device used for L2 forwarding offload 4267 * 4268 * Queue a buffer for transmission to a network device. The caller must 4269 * have set the device and priority and built the buffer before calling 4270 * this function. The function can be called from an interrupt. 4271 * 4272 * When calling this method, interrupts MUST be enabled. This is because 4273 * the BH enable code must have IRQs enabled so that it will not deadlock. 4274 * 4275 * Regardless of the return value, the skb is consumed, so it is currently 4276 * difficult to retry a send to this method. (You can bump the ref count 4277 * before sending to hold a reference for retry if you are careful.) 4278 * 4279 * Return: 4280 * * 0 - buffer successfully transmitted 4281 * * positive qdisc return code - NET_XMIT_DROP etc. 4282 * * negative errno - other errors 4283 */ 4284 int __dev_queue_xmit(struct sk_buff *skb, struct net_device *sb_dev) 4285 { 4286 struct net_device *dev = skb->dev; 4287 struct netdev_queue *txq = NULL; 4288 struct Qdisc *q; 4289 int rc = -ENOMEM; 4290 bool again = false; 4291 4292 skb_reset_mac_header(skb); 4293 skb_assert_len(skb); 4294 4295 if (unlikely(skb_shinfo(skb)->tx_flags & SKBTX_SCHED_TSTAMP)) 4296 __skb_tstamp_tx(skb, NULL, NULL, skb->sk, SCM_TSTAMP_SCHED); 4297 4298 /* Disable soft irqs for various locks below. Also 4299 * stops preemption for RCU. 4300 */ 4301 rcu_read_lock_bh(); 4302 4303 skb_update_prio(skb); 4304 4305 qdisc_pkt_len_init(skb); 4306 tcx_set_ingress(skb, false); 4307 #ifdef CONFIG_NET_EGRESS 4308 if (static_branch_unlikely(&egress_needed_key)) { 4309 if (nf_hook_egress_active()) { 4310 skb = nf_hook_egress(skb, &rc, dev); 4311 if (!skb) 4312 goto out; 4313 } 4314 4315 netdev_xmit_skip_txqueue(false); 4316 4317 nf_skip_egress(skb, true); 4318 skb = sch_handle_egress(skb, &rc, dev); 4319 if (!skb) 4320 goto out; 4321 nf_skip_egress(skb, false); 4322 4323 if (netdev_xmit_txqueue_skipped()) 4324 txq = netdev_tx_queue_mapping(dev, skb); 4325 } 4326 #endif 4327 /* If device/qdisc don't need skb->dst, release it right now while 4328 * its hot in this cpu cache. 4329 */ 4330 if (dev->priv_flags & IFF_XMIT_DST_RELEASE) 4331 skb_dst_drop(skb); 4332 else 4333 skb_dst_force(skb); 4334 4335 if (!txq) 4336 txq = netdev_core_pick_tx(dev, skb, sb_dev); 4337 4338 q = rcu_dereference_bh(txq->qdisc); 4339 4340 trace_net_dev_queue(skb); 4341 if (q->enqueue) { 4342 rc = __dev_xmit_skb(skb, q, dev, txq); 4343 goto out; 4344 } 4345 4346 /* The device has no queue. Common case for software devices: 4347 * loopback, all the sorts of tunnels... 4348 4349 * Really, it is unlikely that netif_tx_lock protection is necessary 4350 * here. (f.e. loopback and IP tunnels are clean ignoring statistics 4351 * counters.) 4352 * However, it is possible, that they rely on protection 4353 * made by us here. 4354 4355 * Check this and shot the lock. It is not prone from deadlocks. 4356 *Either shot noqueue qdisc, it is even simpler 8) 4357 */ 4358 if (dev->flags & IFF_UP) { 4359 int cpu = smp_processor_id(); /* ok because BHs are off */ 4360 4361 /* Other cpus might concurrently change txq->xmit_lock_owner 4362 * to -1 or to their cpu id, but not to our id. 4363 */ 4364 if (READ_ONCE(txq->xmit_lock_owner) != cpu) { 4365 if (dev_xmit_recursion()) 4366 goto recursion_alert; 4367 4368 skb = validate_xmit_skb(skb, dev, &again); 4369 if (!skb) 4370 goto out; 4371 4372 HARD_TX_LOCK(dev, txq, cpu); 4373 4374 if (!netif_xmit_stopped(txq)) { 4375 dev_xmit_recursion_inc(); 4376 skb = dev_hard_start_xmit(skb, dev, txq, &rc); 4377 dev_xmit_recursion_dec(); 4378 if (dev_xmit_complete(rc)) { 4379 HARD_TX_UNLOCK(dev, txq); 4380 goto out; 4381 } 4382 } 4383 HARD_TX_UNLOCK(dev, txq); 4384 net_crit_ratelimited("Virtual device %s asks to queue packet!\n", 4385 dev->name); 4386 } else { 4387 /* Recursion is detected! It is possible, 4388 * unfortunately 4389 */ 4390 recursion_alert: 4391 net_crit_ratelimited("Dead loop on virtual device %s, fix it urgently!\n", 4392 dev->name); 4393 } 4394 } 4395 4396 rc = -ENETDOWN; 4397 rcu_read_unlock_bh(); 4398 4399 dev_core_stats_tx_dropped_inc(dev); 4400 kfree_skb_list(skb); 4401 return rc; 4402 out: 4403 rcu_read_unlock_bh(); 4404 return rc; 4405 } 4406 EXPORT_SYMBOL(__dev_queue_xmit); 4407 4408 int __dev_direct_xmit(struct sk_buff *skb, u16 queue_id) 4409 { 4410 struct net_device *dev = skb->dev; 4411 struct sk_buff *orig_skb = skb; 4412 struct netdev_queue *txq; 4413 int ret = NETDEV_TX_BUSY; 4414 bool again = false; 4415 4416 if (unlikely(!netif_running(dev) || 4417 !netif_carrier_ok(dev))) 4418 goto drop; 4419 4420 skb = validate_xmit_skb_list(skb, dev, &again); 4421 if (skb != orig_skb) 4422 goto drop; 4423 4424 skb_set_queue_mapping(skb, queue_id); 4425 txq = skb_get_tx_queue(dev, skb); 4426 4427 local_bh_disable(); 4428 4429 dev_xmit_recursion_inc(); 4430 HARD_TX_LOCK(dev, txq, smp_processor_id()); 4431 if (!netif_xmit_frozen_or_drv_stopped(txq)) 4432 ret = netdev_start_xmit(skb, dev, txq, false); 4433 HARD_TX_UNLOCK(dev, txq); 4434 dev_xmit_recursion_dec(); 4435 4436 local_bh_enable(); 4437 return ret; 4438 drop: 4439 dev_core_stats_tx_dropped_inc(dev); 4440 kfree_skb_list(skb); 4441 return NET_XMIT_DROP; 4442 } 4443 EXPORT_SYMBOL(__dev_direct_xmit); 4444 4445 /************************************************************************* 4446 * Receiver routines 4447 *************************************************************************/ 4448 4449 int netdev_max_backlog __read_mostly = 1000; 4450 EXPORT_SYMBOL(netdev_max_backlog); 4451 4452 int netdev_tstamp_prequeue __read_mostly = 1; 4453 unsigned int sysctl_skb_defer_max __read_mostly = 64; 4454 int netdev_budget __read_mostly = 300; 4455 /* Must be at least 2 jiffes to guarantee 1 jiffy timeout */ 4456 unsigned int __read_mostly netdev_budget_usecs = 2 * USEC_PER_SEC / HZ; 4457 int weight_p __read_mostly = 64; /* old backlog weight */ 4458 int dev_weight_rx_bias __read_mostly = 1; /* bias for backlog weight */ 4459 int dev_weight_tx_bias __read_mostly = 1; /* bias for output_queue quota */ 4460 int dev_rx_weight __read_mostly = 64; 4461 int dev_tx_weight __read_mostly = 64; 4462 4463 /* Called with irq disabled */ 4464 static inline void ____napi_schedule(struct softnet_data *sd, 4465 struct napi_struct *napi) 4466 { 4467 struct task_struct *thread; 4468 4469 lockdep_assert_irqs_disabled(); 4470 4471 if (test_bit(NAPI_STATE_THREADED, &napi->state)) { 4472 /* Paired with smp_mb__before_atomic() in 4473 * napi_enable()/dev_set_threaded(). 4474 * Use READ_ONCE() to guarantee a complete 4475 * read on napi->thread. Only call 4476 * wake_up_process() when it's not NULL. 4477 */ 4478 thread = READ_ONCE(napi->thread); 4479 if (thread) { 4480 /* Avoid doing set_bit() if the thread is in 4481 * INTERRUPTIBLE state, cause napi_thread_wait() 4482 * makes sure to proceed with napi polling 4483 * if the thread is explicitly woken from here. 4484 */ 4485 if (READ_ONCE(thread->__state) != TASK_INTERRUPTIBLE) 4486 set_bit(NAPI_STATE_SCHED_THREADED, &napi->state); 4487 wake_up_process(thread); 4488 return; 4489 } 4490 } 4491 4492 list_add_tail(&napi->poll_list, &sd->poll_list); 4493 WRITE_ONCE(napi->list_owner, smp_processor_id()); 4494 /* If not called from net_rx_action() 4495 * we have to raise NET_RX_SOFTIRQ. 4496 */ 4497 if (!sd->in_net_rx_action) 4498 __raise_softirq_irqoff(NET_RX_SOFTIRQ); 4499 } 4500 4501 #ifdef CONFIG_RPS 4502 4503 /* One global table that all flow-based protocols share. */ 4504 struct rps_sock_flow_table __rcu *rps_sock_flow_table __read_mostly; 4505 EXPORT_SYMBOL(rps_sock_flow_table); 4506 u32 rps_cpu_mask __read_mostly; 4507 EXPORT_SYMBOL(rps_cpu_mask); 4508 4509 struct static_key_false rps_needed __read_mostly; 4510 EXPORT_SYMBOL(rps_needed); 4511 struct static_key_false rfs_needed __read_mostly; 4512 EXPORT_SYMBOL(rfs_needed); 4513 4514 static struct rps_dev_flow * 4515 set_rps_cpu(struct net_device *dev, struct sk_buff *skb, 4516 struct rps_dev_flow *rflow, u16 next_cpu) 4517 { 4518 if (next_cpu < nr_cpu_ids) { 4519 #ifdef CONFIG_RFS_ACCEL 4520 struct netdev_rx_queue *rxqueue; 4521 struct rps_dev_flow_table *flow_table; 4522 struct rps_dev_flow *old_rflow; 4523 u32 flow_id; 4524 u16 rxq_index; 4525 int rc; 4526 4527 /* Should we steer this flow to a different hardware queue? */ 4528 if (!skb_rx_queue_recorded(skb) || !dev->rx_cpu_rmap || 4529 !(dev->features & NETIF_F_NTUPLE)) 4530 goto out; 4531 rxq_index = cpu_rmap_lookup_index(dev->rx_cpu_rmap, next_cpu); 4532 if (rxq_index == skb_get_rx_queue(skb)) 4533 goto out; 4534 4535 rxqueue = dev->_rx + rxq_index; 4536 flow_table = rcu_dereference(rxqueue->rps_flow_table); 4537 if (!flow_table) 4538 goto out; 4539 flow_id = skb_get_hash(skb) & flow_table->mask; 4540 rc = dev->netdev_ops->ndo_rx_flow_steer(dev, skb, 4541 rxq_index, flow_id); 4542 if (rc < 0) 4543 goto out; 4544 old_rflow = rflow; 4545 rflow = &flow_table->flows[flow_id]; 4546 rflow->filter = rc; 4547 if (old_rflow->filter == rflow->filter) 4548 old_rflow->filter = RPS_NO_FILTER; 4549 out: 4550 #endif 4551 rflow->last_qtail = 4552 per_cpu(softnet_data, next_cpu).input_queue_head; 4553 } 4554 4555 rflow->cpu = next_cpu; 4556 return rflow; 4557 } 4558 4559 /* 4560 * get_rps_cpu is called from netif_receive_skb and returns the target 4561 * CPU from the RPS map of the receiving queue for a given skb. 4562 * rcu_read_lock must be held on entry. 4563 */ 4564 static int get_rps_cpu(struct net_device *dev, struct sk_buff *skb, 4565 struct rps_dev_flow **rflowp) 4566 { 4567 const struct rps_sock_flow_table *sock_flow_table; 4568 struct netdev_rx_queue *rxqueue = dev->_rx; 4569 struct rps_dev_flow_table *flow_table; 4570 struct rps_map *map; 4571 int cpu = -1; 4572 u32 tcpu; 4573 u32 hash; 4574 4575 if (skb_rx_queue_recorded(skb)) { 4576 u16 index = skb_get_rx_queue(skb); 4577 4578 if (unlikely(index >= dev->real_num_rx_queues)) { 4579 WARN_ONCE(dev->real_num_rx_queues > 1, 4580 "%s received packet on queue %u, but number " 4581 "of RX queues is %u\n", 4582 dev->name, index, dev->real_num_rx_queues); 4583 goto done; 4584 } 4585 rxqueue += index; 4586 } 4587 4588 /* Avoid computing hash if RFS/RPS is not active for this rxqueue */ 4589 4590 flow_table = rcu_dereference(rxqueue->rps_flow_table); 4591 map = rcu_dereference(rxqueue->rps_map); 4592 if (!flow_table && !map) 4593 goto done; 4594 4595 skb_reset_network_header(skb); 4596 hash = skb_get_hash(skb); 4597 if (!hash) 4598 goto done; 4599 4600 sock_flow_table = rcu_dereference(rps_sock_flow_table); 4601 if (flow_table && sock_flow_table) { 4602 struct rps_dev_flow *rflow; 4603 u32 next_cpu; 4604 u32 ident; 4605 4606 /* First check into global flow table if there is a match. 4607 * This READ_ONCE() pairs with WRITE_ONCE() from rps_record_sock_flow(). 4608 */ 4609 ident = READ_ONCE(sock_flow_table->ents[hash & sock_flow_table->mask]); 4610 if ((ident ^ hash) & ~rps_cpu_mask) 4611 goto try_rps; 4612 4613 next_cpu = ident & rps_cpu_mask; 4614 4615 /* OK, now we know there is a match, 4616 * we can look at the local (per receive queue) flow table 4617 */ 4618 rflow = &flow_table->flows[hash & flow_table->mask]; 4619 tcpu = rflow->cpu; 4620 4621 /* 4622 * If the desired CPU (where last recvmsg was done) is 4623 * different from current CPU (one in the rx-queue flow 4624 * table entry), switch if one of the following holds: 4625 * - Current CPU is unset (>= nr_cpu_ids). 4626 * - Current CPU is offline. 4627 * - The current CPU's queue tail has advanced beyond the 4628 * last packet that was enqueued using this table entry. 4629 * This guarantees that all previous packets for the flow 4630 * have been dequeued, thus preserving in order delivery. 4631 */ 4632 if (unlikely(tcpu != next_cpu) && 4633 (tcpu >= nr_cpu_ids || !cpu_online(tcpu) || 4634 ((int)(per_cpu(softnet_data, tcpu).input_queue_head - 4635 rflow->last_qtail)) >= 0)) { 4636 tcpu = next_cpu; 4637 rflow = set_rps_cpu(dev, skb, rflow, next_cpu); 4638 } 4639 4640 if (tcpu < nr_cpu_ids && cpu_online(tcpu)) { 4641 *rflowp = rflow; 4642 cpu = tcpu; 4643 goto done; 4644 } 4645 } 4646 4647 try_rps: 4648 4649 if (map) { 4650 tcpu = map->cpus[reciprocal_scale(hash, map->len)]; 4651 if (cpu_online(tcpu)) { 4652 cpu = tcpu; 4653 goto done; 4654 } 4655 } 4656 4657 done: 4658 return cpu; 4659 } 4660 4661 #ifdef CONFIG_RFS_ACCEL 4662 4663 /** 4664 * rps_may_expire_flow - check whether an RFS hardware filter may be removed 4665 * @dev: Device on which the filter was set 4666 * @rxq_index: RX queue index 4667 * @flow_id: Flow ID passed to ndo_rx_flow_steer() 4668 * @filter_id: Filter ID returned by ndo_rx_flow_steer() 4669 * 4670 * Drivers that implement ndo_rx_flow_steer() should periodically call 4671 * this function for each installed filter and remove the filters for 4672 * which it returns %true. 4673 */ 4674 bool rps_may_expire_flow(struct net_device *dev, u16 rxq_index, 4675 u32 flow_id, u16 filter_id) 4676 { 4677 struct netdev_rx_queue *rxqueue = dev->_rx + rxq_index; 4678 struct rps_dev_flow_table *flow_table; 4679 struct rps_dev_flow *rflow; 4680 bool expire = true; 4681 unsigned int cpu; 4682 4683 rcu_read_lock(); 4684 flow_table = rcu_dereference(rxqueue->rps_flow_table); 4685 if (flow_table && flow_id <= flow_table->mask) { 4686 rflow = &flow_table->flows[flow_id]; 4687 cpu = READ_ONCE(rflow->cpu); 4688 if (rflow->filter == filter_id && cpu < nr_cpu_ids && 4689 ((int)(per_cpu(softnet_data, cpu).input_queue_head - 4690 rflow->last_qtail) < 4691 (int)(10 * flow_table->mask))) 4692 expire = false; 4693 } 4694 rcu_read_unlock(); 4695 return expire; 4696 } 4697 EXPORT_SYMBOL(rps_may_expire_flow); 4698 4699 #endif /* CONFIG_RFS_ACCEL */ 4700 4701 /* Called from hardirq (IPI) context */ 4702 static void rps_trigger_softirq(void *data) 4703 { 4704 struct softnet_data *sd = data; 4705 4706 ____napi_schedule(sd, &sd->backlog); 4707 sd->received_rps++; 4708 } 4709 4710 #endif /* CONFIG_RPS */ 4711 4712 /* Called from hardirq (IPI) context */ 4713 static void trigger_rx_softirq(void *data) 4714 { 4715 struct softnet_data *sd = data; 4716 4717 __raise_softirq_irqoff(NET_RX_SOFTIRQ); 4718 smp_store_release(&sd->defer_ipi_scheduled, 0); 4719 } 4720 4721 /* 4722 * After we queued a packet into sd->input_pkt_queue, 4723 * we need to make sure this queue is serviced soon. 4724 * 4725 * - If this is another cpu queue, link it to our rps_ipi_list, 4726 * and make sure we will process rps_ipi_list from net_rx_action(). 4727 * 4728 * - If this is our own queue, NAPI schedule our backlog. 4729 * Note that this also raises NET_RX_SOFTIRQ. 4730 */ 4731 static void napi_schedule_rps(struct softnet_data *sd) 4732 { 4733 struct softnet_data *mysd = this_cpu_ptr(&softnet_data); 4734 4735 #ifdef CONFIG_RPS 4736 if (sd != mysd) { 4737 sd->rps_ipi_next = mysd->rps_ipi_list; 4738 mysd->rps_ipi_list = sd; 4739 4740 /* If not called from net_rx_action() or napi_threaded_poll() 4741 * we have to raise NET_RX_SOFTIRQ. 4742 */ 4743 if (!mysd->in_net_rx_action && !mysd->in_napi_threaded_poll) 4744 __raise_softirq_irqoff(NET_RX_SOFTIRQ); 4745 return; 4746 } 4747 #endif /* CONFIG_RPS */ 4748 __napi_schedule_irqoff(&mysd->backlog); 4749 } 4750 4751 #ifdef CONFIG_NET_FLOW_LIMIT 4752 int netdev_flow_limit_table_len __read_mostly = (1 << 12); 4753 #endif 4754 4755 static bool skb_flow_limit(struct sk_buff *skb, unsigned int qlen) 4756 { 4757 #ifdef CONFIG_NET_FLOW_LIMIT 4758 struct sd_flow_limit *fl; 4759 struct softnet_data *sd; 4760 unsigned int old_flow, new_flow; 4761 4762 if (qlen < (READ_ONCE(netdev_max_backlog) >> 1)) 4763 return false; 4764 4765 sd = this_cpu_ptr(&softnet_data); 4766 4767 rcu_read_lock(); 4768 fl = rcu_dereference(sd->flow_limit); 4769 if (fl) { 4770 new_flow = skb_get_hash(skb) & (fl->num_buckets - 1); 4771 old_flow = fl->history[fl->history_head]; 4772 fl->history[fl->history_head] = new_flow; 4773 4774 fl->history_head++; 4775 fl->history_head &= FLOW_LIMIT_HISTORY - 1; 4776 4777 if (likely(fl->buckets[old_flow])) 4778 fl->buckets[old_flow]--; 4779 4780 if (++fl->buckets[new_flow] > (FLOW_LIMIT_HISTORY >> 1)) { 4781 fl->count++; 4782 rcu_read_unlock(); 4783 return true; 4784 } 4785 } 4786 rcu_read_unlock(); 4787 #endif 4788 return false; 4789 } 4790 4791 /* 4792 * enqueue_to_backlog is called to queue an skb to a per CPU backlog 4793 * queue (may be a remote CPU queue). 4794 */ 4795 static int enqueue_to_backlog(struct sk_buff *skb, int cpu, 4796 unsigned int *qtail) 4797 { 4798 enum skb_drop_reason reason; 4799 struct softnet_data *sd; 4800 unsigned long flags; 4801 unsigned int qlen; 4802 4803 reason = SKB_DROP_REASON_NOT_SPECIFIED; 4804 sd = &per_cpu(softnet_data, cpu); 4805 4806 rps_lock_irqsave(sd, &flags); 4807 if (!netif_running(skb->dev)) 4808 goto drop; 4809 qlen = skb_queue_len(&sd->input_pkt_queue); 4810 if (qlen <= READ_ONCE(netdev_max_backlog) && !skb_flow_limit(skb, qlen)) { 4811 if (qlen) { 4812 enqueue: 4813 __skb_queue_tail(&sd->input_pkt_queue, skb); 4814 input_queue_tail_incr_save(sd, qtail); 4815 rps_unlock_irq_restore(sd, &flags); 4816 return NET_RX_SUCCESS; 4817 } 4818 4819 /* Schedule NAPI for backlog device 4820 * We can use non atomic operation since we own the queue lock 4821 */ 4822 if (!__test_and_set_bit(NAPI_STATE_SCHED, &sd->backlog.state)) 4823 napi_schedule_rps(sd); 4824 goto enqueue; 4825 } 4826 reason = SKB_DROP_REASON_CPU_BACKLOG; 4827 4828 drop: 4829 sd->dropped++; 4830 rps_unlock_irq_restore(sd, &flags); 4831 4832 dev_core_stats_rx_dropped_inc(skb->dev); 4833 kfree_skb_reason(skb, reason); 4834 return NET_RX_DROP; 4835 } 4836 4837 static struct netdev_rx_queue *netif_get_rxqueue(struct sk_buff *skb) 4838 { 4839 struct net_device *dev = skb->dev; 4840 struct netdev_rx_queue *rxqueue; 4841 4842 rxqueue = dev->_rx; 4843 4844 if (skb_rx_queue_recorded(skb)) { 4845 u16 index = skb_get_rx_queue(skb); 4846 4847 if (unlikely(index >= dev->real_num_rx_queues)) { 4848 WARN_ONCE(dev->real_num_rx_queues > 1, 4849 "%s received packet on queue %u, but number " 4850 "of RX queues is %u\n", 4851 dev->name, index, dev->real_num_rx_queues); 4852 4853 return rxqueue; /* Return first rxqueue */ 4854 } 4855 rxqueue += index; 4856 } 4857 return rxqueue; 4858 } 4859 4860 u32 bpf_prog_run_generic_xdp(struct sk_buff *skb, struct xdp_buff *xdp, 4861 struct bpf_prog *xdp_prog) 4862 { 4863 void *orig_data, *orig_data_end, *hard_start; 4864 struct netdev_rx_queue *rxqueue; 4865 bool orig_bcast, orig_host; 4866 u32 mac_len, frame_sz; 4867 __be16 orig_eth_type; 4868 struct ethhdr *eth; 4869 u32 metalen, act; 4870 int off; 4871 4872 /* The XDP program wants to see the packet starting at the MAC 4873 * header. 4874 */ 4875 mac_len = skb->data - skb_mac_header(skb); 4876 hard_start = skb->data - skb_headroom(skb); 4877 4878 /* SKB "head" area always have tailroom for skb_shared_info */ 4879 frame_sz = (void *)skb_end_pointer(skb) - hard_start; 4880 frame_sz += SKB_DATA_ALIGN(sizeof(struct skb_shared_info)); 4881 4882 rxqueue = netif_get_rxqueue(skb); 4883 xdp_init_buff(xdp, frame_sz, &rxqueue->xdp_rxq); 4884 xdp_prepare_buff(xdp, hard_start, skb_headroom(skb) - mac_len, 4885 skb_headlen(skb) + mac_len, true); 4886 4887 orig_data_end = xdp->data_end; 4888 orig_data = xdp->data; 4889 eth = (struct ethhdr *)xdp->data; 4890 orig_host = ether_addr_equal_64bits(eth->h_dest, skb->dev->dev_addr); 4891 orig_bcast = is_multicast_ether_addr_64bits(eth->h_dest); 4892 orig_eth_type = eth->h_proto; 4893 4894 act = bpf_prog_run_xdp(xdp_prog, xdp); 4895 4896 /* check if bpf_xdp_adjust_head was used */ 4897 off = xdp->data - orig_data; 4898 if (off) { 4899 if (off > 0) 4900 __skb_pull(skb, off); 4901 else if (off < 0) 4902 __skb_push(skb, -off); 4903 4904 skb->mac_header += off; 4905 skb_reset_network_header(skb); 4906 } 4907 4908 /* check if bpf_xdp_adjust_tail was used */ 4909 off = xdp->data_end - orig_data_end; 4910 if (off != 0) { 4911 skb_set_tail_pointer(skb, xdp->data_end - xdp->data); 4912 skb->len += off; /* positive on grow, negative on shrink */ 4913 } 4914 4915 /* check if XDP changed eth hdr such SKB needs update */ 4916 eth = (struct ethhdr *)xdp->data; 4917 if ((orig_eth_type != eth->h_proto) || 4918 (orig_host != ether_addr_equal_64bits(eth->h_dest, 4919 skb->dev->dev_addr)) || 4920 (orig_bcast != is_multicast_ether_addr_64bits(eth->h_dest))) { 4921 __skb_push(skb, ETH_HLEN); 4922 skb->pkt_type = PACKET_HOST; 4923 skb->protocol = eth_type_trans(skb, skb->dev); 4924 } 4925 4926 /* Redirect/Tx gives L2 packet, code that will reuse skb must __skb_pull 4927 * before calling us again on redirect path. We do not call do_redirect 4928 * as we leave that up to the caller. 4929 * 4930 * Caller is responsible for managing lifetime of skb (i.e. calling 4931 * kfree_skb in response to actions it cannot handle/XDP_DROP). 4932 */ 4933 switch (act) { 4934 case XDP_REDIRECT: 4935 case XDP_TX: 4936 __skb_push(skb, mac_len); 4937 break; 4938 case XDP_PASS: 4939 metalen = xdp->data - xdp->data_meta; 4940 if (metalen) 4941 skb_metadata_set(skb, metalen); 4942 break; 4943 } 4944 4945 return act; 4946 } 4947 4948 static u32 netif_receive_generic_xdp(struct sk_buff *skb, 4949 struct xdp_buff *xdp, 4950 struct bpf_prog *xdp_prog) 4951 { 4952 u32 act = XDP_DROP; 4953 4954 /* Reinjected packets coming from act_mirred or similar should 4955 * not get XDP generic processing. 4956 */ 4957 if (skb_is_redirected(skb)) 4958 return XDP_PASS; 4959 4960 /* XDP packets must be linear and must have sufficient headroom 4961 * of XDP_PACKET_HEADROOM bytes. This is the guarantee that also 4962 * native XDP provides, thus we need to do it here as well. 4963 */ 4964 if (skb_cloned(skb) || skb_is_nonlinear(skb) || 4965 skb_headroom(skb) < XDP_PACKET_HEADROOM) { 4966 int hroom = XDP_PACKET_HEADROOM - skb_headroom(skb); 4967 int troom = skb->tail + skb->data_len - skb->end; 4968 4969 /* In case we have to go down the path and also linearize, 4970 * then lets do the pskb_expand_head() work just once here. 4971 */ 4972 if (pskb_expand_head(skb, 4973 hroom > 0 ? ALIGN(hroom, NET_SKB_PAD) : 0, 4974 troom > 0 ? troom + 128 : 0, GFP_ATOMIC)) 4975 goto do_drop; 4976 if (skb_linearize(skb)) 4977 goto do_drop; 4978 } 4979 4980 act = bpf_prog_run_generic_xdp(skb, xdp, xdp_prog); 4981 switch (act) { 4982 case XDP_REDIRECT: 4983 case XDP_TX: 4984 case XDP_PASS: 4985 break; 4986 default: 4987 bpf_warn_invalid_xdp_action(skb->dev, xdp_prog, act); 4988 fallthrough; 4989 case XDP_ABORTED: 4990 trace_xdp_exception(skb->dev, xdp_prog, act); 4991 fallthrough; 4992 case XDP_DROP: 4993 do_drop: 4994 kfree_skb(skb); 4995 break; 4996 } 4997 4998 return act; 4999 } 5000 5001 /* When doing generic XDP we have to bypass the qdisc layer and the 5002 * network taps in order to match in-driver-XDP behavior. This also means 5003 * that XDP packets are able to starve other packets going through a qdisc, 5004 * and DDOS attacks will be more effective. In-driver-XDP use dedicated TX 5005 * queues, so they do not have this starvation issue. 5006 */ 5007 void generic_xdp_tx(struct sk_buff *skb, struct bpf_prog *xdp_prog) 5008 { 5009 struct net_device *dev = skb->dev; 5010 struct netdev_queue *txq; 5011 bool free_skb = true; 5012 int cpu, rc; 5013 5014 txq = netdev_core_pick_tx(dev, skb, NULL); 5015 cpu = smp_processor_id(); 5016 HARD_TX_LOCK(dev, txq, cpu); 5017 if (!netif_xmit_frozen_or_drv_stopped(txq)) { 5018 rc = netdev_start_xmit(skb, dev, txq, 0); 5019 if (dev_xmit_complete(rc)) 5020 free_skb = false; 5021 } 5022 HARD_TX_UNLOCK(dev, txq); 5023 if (free_skb) { 5024 trace_xdp_exception(dev, xdp_prog, XDP_TX); 5025 dev_core_stats_tx_dropped_inc(dev); 5026 kfree_skb(skb); 5027 } 5028 } 5029 5030 static DEFINE_STATIC_KEY_FALSE(generic_xdp_needed_key); 5031 5032 int do_xdp_generic(struct bpf_prog *xdp_prog, struct sk_buff *skb) 5033 { 5034 if (xdp_prog) { 5035 struct xdp_buff xdp; 5036 u32 act; 5037 int err; 5038 5039 act = netif_receive_generic_xdp(skb, &xdp, xdp_prog); 5040 if (act != XDP_PASS) { 5041 switch (act) { 5042 case XDP_REDIRECT: 5043 err = xdp_do_generic_redirect(skb->dev, skb, 5044 &xdp, xdp_prog); 5045 if (err) 5046 goto out_redir; 5047 break; 5048 case XDP_TX: 5049 generic_xdp_tx(skb, xdp_prog); 5050 break; 5051 } 5052 return XDP_DROP; 5053 } 5054 } 5055 return XDP_PASS; 5056 out_redir: 5057 kfree_skb_reason(skb, SKB_DROP_REASON_XDP); 5058 return XDP_DROP; 5059 } 5060 EXPORT_SYMBOL_GPL(do_xdp_generic); 5061 5062 static int netif_rx_internal(struct sk_buff *skb) 5063 { 5064 int ret; 5065 5066 net_timestamp_check(READ_ONCE(netdev_tstamp_prequeue), skb); 5067 5068 trace_netif_rx(skb); 5069 5070 #ifdef CONFIG_RPS 5071 if (static_branch_unlikely(&rps_needed)) { 5072 struct rps_dev_flow voidflow, *rflow = &voidflow; 5073 int cpu; 5074 5075 rcu_read_lock(); 5076 5077 cpu = get_rps_cpu(skb->dev, skb, &rflow); 5078 if (cpu < 0) 5079 cpu = smp_processor_id(); 5080 5081 ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail); 5082 5083 rcu_read_unlock(); 5084 } else 5085 #endif 5086 { 5087 unsigned int qtail; 5088 5089 ret = enqueue_to_backlog(skb, smp_processor_id(), &qtail); 5090 } 5091 return ret; 5092 } 5093 5094 /** 5095 * __netif_rx - Slightly optimized version of netif_rx 5096 * @skb: buffer to post 5097 * 5098 * This behaves as netif_rx except that it does not disable bottom halves. 5099 * As a result this function may only be invoked from the interrupt context 5100 * (either hard or soft interrupt). 5101 */ 5102 int __netif_rx(struct sk_buff *skb) 5103 { 5104 int ret; 5105 5106 lockdep_assert_once(hardirq_count() | softirq_count()); 5107 5108 trace_netif_rx_entry(skb); 5109 ret = netif_rx_internal(skb); 5110 trace_netif_rx_exit(ret); 5111 return ret; 5112 } 5113 EXPORT_SYMBOL(__netif_rx); 5114 5115 /** 5116 * netif_rx - post buffer to the network code 5117 * @skb: buffer to post 5118 * 5119 * This function receives a packet from a device driver and queues it for 5120 * the upper (protocol) levels to process via the backlog NAPI device. It 5121 * always succeeds. The buffer may be dropped during processing for 5122 * congestion control or by the protocol layers. 5123 * The network buffer is passed via the backlog NAPI device. Modern NIC 5124 * driver should use NAPI and GRO. 5125 * This function can used from interrupt and from process context. The 5126 * caller from process context must not disable interrupts before invoking 5127 * this function. 5128 * 5129 * return values: 5130 * NET_RX_SUCCESS (no congestion) 5131 * NET_RX_DROP (packet was dropped) 5132 * 5133 */ 5134 int netif_rx(struct sk_buff *skb) 5135 { 5136 bool need_bh_off = !(hardirq_count() | softirq_count()); 5137 int ret; 5138 5139 if (need_bh_off) 5140 local_bh_disable(); 5141 trace_netif_rx_entry(skb); 5142 ret = netif_rx_internal(skb); 5143 trace_netif_rx_exit(ret); 5144 if (need_bh_off) 5145 local_bh_enable(); 5146 return ret; 5147 } 5148 EXPORT_SYMBOL(netif_rx); 5149 5150 static __latent_entropy void net_tx_action(struct softirq_action *h) 5151 { 5152 struct softnet_data *sd = this_cpu_ptr(&softnet_data); 5153 5154 if (sd->completion_queue) { 5155 struct sk_buff *clist; 5156 5157 local_irq_disable(); 5158 clist = sd->completion_queue; 5159 sd->completion_queue = NULL; 5160 local_irq_enable(); 5161 5162 while (clist) { 5163 struct sk_buff *skb = clist; 5164 5165 clist = clist->next; 5166 5167 WARN_ON(refcount_read(&skb->users)); 5168 if (likely(get_kfree_skb_cb(skb)->reason == SKB_CONSUMED)) 5169 trace_consume_skb(skb, net_tx_action); 5170 else 5171 trace_kfree_skb(skb, net_tx_action, 5172 get_kfree_skb_cb(skb)->reason); 5173 5174 if (skb->fclone != SKB_FCLONE_UNAVAILABLE) 5175 __kfree_skb(skb); 5176 else 5177 __napi_kfree_skb(skb, 5178 get_kfree_skb_cb(skb)->reason); 5179 } 5180 } 5181 5182 if (sd->output_queue) { 5183 struct Qdisc *head; 5184 5185 local_irq_disable(); 5186 head = sd->output_queue; 5187 sd->output_queue = NULL; 5188 sd->output_queue_tailp = &sd->output_queue; 5189 local_irq_enable(); 5190 5191 rcu_read_lock(); 5192 5193 while (head) { 5194 struct Qdisc *q = head; 5195 spinlock_t *root_lock = NULL; 5196 5197 head = head->next_sched; 5198 5199 /* We need to make sure head->next_sched is read 5200 * before clearing __QDISC_STATE_SCHED 5201 */ 5202 smp_mb__before_atomic(); 5203 5204 if (!(q->flags & TCQ_F_NOLOCK)) { 5205 root_lock = qdisc_lock(q); 5206 spin_lock(root_lock); 5207 } else if (unlikely(test_bit(__QDISC_STATE_DEACTIVATED, 5208 &q->state))) { 5209 /* There is a synchronize_net() between 5210 * STATE_DEACTIVATED flag being set and 5211 * qdisc_reset()/some_qdisc_is_busy() in 5212 * dev_deactivate(), so we can safely bail out 5213 * early here to avoid data race between 5214 * qdisc_deactivate() and some_qdisc_is_busy() 5215 * for lockless qdisc. 5216 */ 5217 clear_bit(__QDISC_STATE_SCHED, &q->state); 5218 continue; 5219 } 5220 5221 clear_bit(__QDISC_STATE_SCHED, &q->state); 5222 qdisc_run(q); 5223 if (root_lock) 5224 spin_unlock(root_lock); 5225 } 5226 5227 rcu_read_unlock(); 5228 } 5229 5230 xfrm_dev_backlog(sd); 5231 } 5232 5233 #if IS_ENABLED(CONFIG_BRIDGE) && IS_ENABLED(CONFIG_ATM_LANE) 5234 /* This hook is defined here for ATM LANE */ 5235 int (*br_fdb_test_addr_hook)(struct net_device *dev, 5236 unsigned char *addr) __read_mostly; 5237 EXPORT_SYMBOL_GPL(br_fdb_test_addr_hook); 5238 #endif 5239 5240 /** 5241 * netdev_is_rx_handler_busy - check if receive handler is registered 5242 * @dev: device to check 5243 * 5244 * Check if a receive handler is already registered for a given device. 5245 * Return true if there one. 5246 * 5247 * The caller must hold the rtnl_mutex. 5248 */ 5249 bool netdev_is_rx_handler_busy(struct net_device *dev) 5250 { 5251 ASSERT_RTNL(); 5252 return dev && rtnl_dereference(dev->rx_handler); 5253 } 5254 EXPORT_SYMBOL_GPL(netdev_is_rx_handler_busy); 5255 5256 /** 5257 * netdev_rx_handler_register - register receive handler 5258 * @dev: device to register a handler for 5259 * @rx_handler: receive handler to register 5260 * @rx_handler_data: data pointer that is used by rx handler 5261 * 5262 * Register a receive handler for a device. This handler will then be 5263 * called from __netif_receive_skb. A negative errno code is returned 5264 * on a failure. 5265 * 5266 * The caller must hold the rtnl_mutex. 5267 * 5268 * For a general description of rx_handler, see enum rx_handler_result. 5269 */ 5270 int netdev_rx_handler_register(struct net_device *dev, 5271 rx_handler_func_t *rx_handler, 5272 void *rx_handler_data) 5273 { 5274 if (netdev_is_rx_handler_busy(dev)) 5275 return -EBUSY; 5276 5277 if (dev->priv_flags & IFF_NO_RX_HANDLER) 5278 return -EINVAL; 5279 5280 /* Note: rx_handler_data must be set before rx_handler */ 5281 rcu_assign_pointer(dev->rx_handler_data, rx_handler_data); 5282 rcu_assign_pointer(dev->rx_handler, rx_handler); 5283 5284 return 0; 5285 } 5286 EXPORT_SYMBOL_GPL(netdev_rx_handler_register); 5287 5288 /** 5289 * netdev_rx_handler_unregister - unregister receive handler 5290 * @dev: device to unregister a handler from 5291 * 5292 * Unregister a receive handler from a device. 5293 * 5294 * The caller must hold the rtnl_mutex. 5295 */ 5296 void netdev_rx_handler_unregister(struct net_device *dev) 5297 { 5298 5299 ASSERT_RTNL(); 5300 RCU_INIT_POINTER(dev->rx_handler, NULL); 5301 /* a reader seeing a non NULL rx_handler in a rcu_read_lock() 5302 * section has a guarantee to see a non NULL rx_handler_data 5303 * as well. 5304 */ 5305 synchronize_net(); 5306 RCU_INIT_POINTER(dev->rx_handler_data, NULL); 5307 } 5308 EXPORT_SYMBOL_GPL(netdev_rx_handler_unregister); 5309 5310 /* 5311 * Limit the use of PFMEMALLOC reserves to those protocols that implement 5312 * the special handling of PFMEMALLOC skbs. 5313 */ 5314 static bool skb_pfmemalloc_protocol(struct sk_buff *skb) 5315 { 5316 switch (skb->protocol) { 5317 case htons(ETH_P_ARP): 5318 case htons(ETH_P_IP): 5319 case htons(ETH_P_IPV6): 5320 case htons(ETH_P_8021Q): 5321 case htons(ETH_P_8021AD): 5322 return true; 5323 default: 5324 return false; 5325 } 5326 } 5327 5328 static inline int nf_ingress(struct sk_buff *skb, struct packet_type **pt_prev, 5329 int *ret, struct net_device *orig_dev) 5330 { 5331 if (nf_hook_ingress_active(skb)) { 5332 int ingress_retval; 5333 5334 if (*pt_prev) { 5335 *ret = deliver_skb(skb, *pt_prev, orig_dev); 5336 *pt_prev = NULL; 5337 } 5338 5339 rcu_read_lock(); 5340 ingress_retval = nf_hook_ingress(skb); 5341 rcu_read_unlock(); 5342 return ingress_retval; 5343 } 5344 return 0; 5345 } 5346 5347 static int __netif_receive_skb_core(struct sk_buff **pskb, bool pfmemalloc, 5348 struct packet_type **ppt_prev) 5349 { 5350 struct packet_type *ptype, *pt_prev; 5351 rx_handler_func_t *rx_handler; 5352 struct sk_buff *skb = *pskb; 5353 struct net_device *orig_dev; 5354 bool deliver_exact = false; 5355 int ret = NET_RX_DROP; 5356 __be16 type; 5357 5358 net_timestamp_check(!READ_ONCE(netdev_tstamp_prequeue), skb); 5359 5360 trace_netif_receive_skb(skb); 5361 5362 orig_dev = skb->dev; 5363 5364 skb_reset_network_header(skb); 5365 if (!skb_transport_header_was_set(skb)) 5366 skb_reset_transport_header(skb); 5367 skb_reset_mac_len(skb); 5368 5369 pt_prev = NULL; 5370 5371 another_round: 5372 skb->skb_iif = skb->dev->ifindex; 5373 5374 __this_cpu_inc(softnet_data.processed); 5375 5376 if (static_branch_unlikely(&generic_xdp_needed_key)) { 5377 int ret2; 5378 5379 migrate_disable(); 5380 ret2 = do_xdp_generic(rcu_dereference(skb->dev->xdp_prog), skb); 5381 migrate_enable(); 5382 5383 if (ret2 != XDP_PASS) { 5384 ret = NET_RX_DROP; 5385 goto out; 5386 } 5387 } 5388 5389 if (eth_type_vlan(skb->protocol)) { 5390 skb = skb_vlan_untag(skb); 5391 if (unlikely(!skb)) 5392 goto out; 5393 } 5394 5395 if (skb_skip_tc_classify(skb)) 5396 goto skip_classify; 5397 5398 if (pfmemalloc) 5399 goto skip_taps; 5400 5401 list_for_each_entry_rcu(ptype, &ptype_all, list) { 5402 if (pt_prev) 5403 ret = deliver_skb(skb, pt_prev, orig_dev); 5404 pt_prev = ptype; 5405 } 5406 5407 list_for_each_entry_rcu(ptype, &skb->dev->ptype_all, list) { 5408 if (pt_prev) 5409 ret = deliver_skb(skb, pt_prev, orig_dev); 5410 pt_prev = ptype; 5411 } 5412 5413 skip_taps: 5414 #ifdef CONFIG_NET_INGRESS 5415 if (static_branch_unlikely(&ingress_needed_key)) { 5416 bool another = false; 5417 5418 nf_skip_egress(skb, true); 5419 skb = sch_handle_ingress(skb, &pt_prev, &ret, orig_dev, 5420 &another); 5421 if (another) 5422 goto another_round; 5423 if (!skb) 5424 goto out; 5425 5426 nf_skip_egress(skb, false); 5427 if (nf_ingress(skb, &pt_prev, &ret, orig_dev) < 0) 5428 goto out; 5429 } 5430 #endif 5431 skb_reset_redirect(skb); 5432 skip_classify: 5433 if (pfmemalloc && !skb_pfmemalloc_protocol(skb)) 5434 goto drop; 5435 5436 if (skb_vlan_tag_present(skb)) { 5437 if (pt_prev) { 5438 ret = deliver_skb(skb, pt_prev, orig_dev); 5439 pt_prev = NULL; 5440 } 5441 if (vlan_do_receive(&skb)) 5442 goto another_round; 5443 else if (unlikely(!skb)) 5444 goto out; 5445 } 5446 5447 rx_handler = rcu_dereference(skb->dev->rx_handler); 5448 if (rx_handler) { 5449 if (pt_prev) { 5450 ret = deliver_skb(skb, pt_prev, orig_dev); 5451 pt_prev = NULL; 5452 } 5453 switch (rx_handler(&skb)) { 5454 case RX_HANDLER_CONSUMED: 5455 ret = NET_RX_SUCCESS; 5456 goto out; 5457 case RX_HANDLER_ANOTHER: 5458 goto another_round; 5459 case RX_HANDLER_EXACT: 5460 deliver_exact = true; 5461 break; 5462 case RX_HANDLER_PASS: 5463 break; 5464 default: 5465 BUG(); 5466 } 5467 } 5468 5469 if (unlikely(skb_vlan_tag_present(skb)) && !netdev_uses_dsa(skb->dev)) { 5470 check_vlan_id: 5471 if (skb_vlan_tag_get_id(skb)) { 5472 /* Vlan id is non 0 and vlan_do_receive() above couldn't 5473 * find vlan device. 5474 */ 5475 skb->pkt_type = PACKET_OTHERHOST; 5476 } else if (eth_type_vlan(skb->protocol)) { 5477 /* Outer header is 802.1P with vlan 0, inner header is 5478 * 802.1Q or 802.1AD and vlan_do_receive() above could 5479 * not find vlan dev for vlan id 0. 5480 */ 5481 __vlan_hwaccel_clear_tag(skb); 5482 skb = skb_vlan_untag(skb); 5483 if (unlikely(!skb)) 5484 goto out; 5485 if (vlan_do_receive(&skb)) 5486 /* After stripping off 802.1P header with vlan 0 5487 * vlan dev is found for inner header. 5488 */ 5489 goto another_round; 5490 else if (unlikely(!skb)) 5491 goto out; 5492 else 5493 /* We have stripped outer 802.1P vlan 0 header. 5494 * But could not find vlan dev. 5495 * check again for vlan id to set OTHERHOST. 5496 */ 5497 goto check_vlan_id; 5498 } 5499 /* Note: we might in the future use prio bits 5500 * and set skb->priority like in vlan_do_receive() 5501 * For the time being, just ignore Priority Code Point 5502 */ 5503 __vlan_hwaccel_clear_tag(skb); 5504 } 5505 5506 type = skb->protocol; 5507 5508 /* deliver only exact match when indicated */ 5509 if (likely(!deliver_exact)) { 5510 deliver_ptype_list_skb(skb, &pt_prev, orig_dev, type, 5511 &ptype_base[ntohs(type) & 5512 PTYPE_HASH_MASK]); 5513 } 5514 5515 deliver_ptype_list_skb(skb, &pt_prev, orig_dev, type, 5516 &orig_dev->ptype_specific); 5517 5518 if (unlikely(skb->dev != orig_dev)) { 5519 deliver_ptype_list_skb(skb, &pt_prev, orig_dev, type, 5520 &skb->dev->ptype_specific); 5521 } 5522 5523 if (pt_prev) { 5524 if (unlikely(skb_orphan_frags_rx(skb, GFP_ATOMIC))) 5525 goto drop; 5526 *ppt_prev = pt_prev; 5527 } else { 5528 drop: 5529 if (!deliver_exact) 5530 dev_core_stats_rx_dropped_inc(skb->dev); 5531 else 5532 dev_core_stats_rx_nohandler_inc(skb->dev); 5533 kfree_skb_reason(skb, SKB_DROP_REASON_UNHANDLED_PROTO); 5534 /* Jamal, now you will not able to escape explaining 5535 * me how you were going to use this. :-) 5536 */ 5537 ret = NET_RX_DROP; 5538 } 5539 5540 out: 5541 /* The invariant here is that if *ppt_prev is not NULL 5542 * then skb should also be non-NULL. 5543 * 5544 * Apparently *ppt_prev assignment above holds this invariant due to 5545 * skb dereferencing near it. 5546 */ 5547 *pskb = skb; 5548 return ret; 5549 } 5550 5551 static int __netif_receive_skb_one_core(struct sk_buff *skb, bool pfmemalloc) 5552 { 5553 struct net_device *orig_dev = skb->dev; 5554 struct packet_type *pt_prev = NULL; 5555 int ret; 5556 5557 ret = __netif_receive_skb_core(&skb, pfmemalloc, &pt_prev); 5558 if (pt_prev) 5559 ret = INDIRECT_CALL_INET(pt_prev->func, ipv6_rcv, ip_rcv, skb, 5560 skb->dev, pt_prev, orig_dev); 5561 return ret; 5562 } 5563 5564 /** 5565 * netif_receive_skb_core - special purpose version of netif_receive_skb 5566 * @skb: buffer to process 5567 * 5568 * More direct receive version of netif_receive_skb(). It should 5569 * only be used by callers that have a need to skip RPS and Generic XDP. 5570 * Caller must also take care of handling if ``(page_is_)pfmemalloc``. 5571 * 5572 * This function may only be called from softirq context and interrupts 5573 * should be enabled. 5574 * 5575 * Return values (usually ignored): 5576 * NET_RX_SUCCESS: no congestion 5577 * NET_RX_DROP: packet was dropped 5578 */ 5579 int netif_receive_skb_core(struct sk_buff *skb) 5580 { 5581 int ret; 5582 5583 rcu_read_lock(); 5584 ret = __netif_receive_skb_one_core(skb, false); 5585 rcu_read_unlock(); 5586 5587 return ret; 5588 } 5589 EXPORT_SYMBOL(netif_receive_skb_core); 5590 5591 static inline void __netif_receive_skb_list_ptype(struct list_head *head, 5592 struct packet_type *pt_prev, 5593 struct net_device *orig_dev) 5594 { 5595 struct sk_buff *skb, *next; 5596 5597 if (!pt_prev) 5598 return; 5599 if (list_empty(head)) 5600 return; 5601 if (pt_prev->list_func != NULL) 5602 INDIRECT_CALL_INET(pt_prev->list_func, ipv6_list_rcv, 5603 ip_list_rcv, head, pt_prev, orig_dev); 5604 else 5605 list_for_each_entry_safe(skb, next, head, list) { 5606 skb_list_del_init(skb); 5607 pt_prev->func(skb, skb->dev, pt_prev, orig_dev); 5608 } 5609 } 5610 5611 static void __netif_receive_skb_list_core(struct list_head *head, bool pfmemalloc) 5612 { 5613 /* Fast-path assumptions: 5614 * - There is no RX handler. 5615 * - Only one packet_type matches. 5616 * If either of these fails, we will end up doing some per-packet 5617 * processing in-line, then handling the 'last ptype' for the whole 5618 * sublist. This can't cause out-of-order delivery to any single ptype, 5619 * because the 'last ptype' must be constant across the sublist, and all 5620 * other ptypes are handled per-packet. 5621 */ 5622 /* Current (common) ptype of sublist */ 5623 struct packet_type *pt_curr = NULL; 5624 /* Current (common) orig_dev of sublist */ 5625 struct net_device *od_curr = NULL; 5626 struct list_head sublist; 5627 struct sk_buff *skb, *next; 5628 5629 INIT_LIST_HEAD(&sublist); 5630 list_for_each_entry_safe(skb, next, head, list) { 5631 struct net_device *orig_dev = skb->dev; 5632 struct packet_type *pt_prev = NULL; 5633 5634 skb_list_del_init(skb); 5635 __netif_receive_skb_core(&skb, pfmemalloc, &pt_prev); 5636 if (!pt_prev) 5637 continue; 5638 if (pt_curr != pt_prev || od_curr != orig_dev) { 5639 /* dispatch old sublist */ 5640 __netif_receive_skb_list_ptype(&sublist, pt_curr, od_curr); 5641 /* start new sublist */ 5642 INIT_LIST_HEAD(&sublist); 5643 pt_curr = pt_prev; 5644 od_curr = orig_dev; 5645 } 5646 list_add_tail(&skb->list, &sublist); 5647 } 5648 5649 /* dispatch final sublist */ 5650 __netif_receive_skb_list_ptype(&sublist, pt_curr, od_curr); 5651 } 5652 5653 static int __netif_receive_skb(struct sk_buff *skb) 5654 { 5655 int ret; 5656 5657 if (sk_memalloc_socks() && skb_pfmemalloc(skb)) { 5658 unsigned int noreclaim_flag; 5659 5660 /* 5661 * PFMEMALLOC skbs are special, they should 5662 * - be delivered to SOCK_MEMALLOC sockets only 5663 * - stay away from userspace 5664 * - have bounded memory usage 5665 * 5666 * Use PF_MEMALLOC as this saves us from propagating the allocation 5667 * context down to all allocation sites. 5668 */ 5669 noreclaim_flag = memalloc_noreclaim_save(); 5670 ret = __netif_receive_skb_one_core(skb, true); 5671 memalloc_noreclaim_restore(noreclaim_flag); 5672 } else 5673 ret = __netif_receive_skb_one_core(skb, false); 5674 5675 return ret; 5676 } 5677 5678 static void __netif_receive_skb_list(struct list_head *head) 5679 { 5680 unsigned long noreclaim_flag = 0; 5681 struct sk_buff *skb, *next; 5682 bool pfmemalloc = false; /* Is current sublist PF_MEMALLOC? */ 5683 5684 list_for_each_entry_safe(skb, next, head, list) { 5685 if ((sk_memalloc_socks() && skb_pfmemalloc(skb)) != pfmemalloc) { 5686 struct list_head sublist; 5687 5688 /* Handle the previous sublist */ 5689 list_cut_before(&sublist, head, &skb->list); 5690 if (!list_empty(&sublist)) 5691 __netif_receive_skb_list_core(&sublist, pfmemalloc); 5692 pfmemalloc = !pfmemalloc; 5693 /* See comments in __netif_receive_skb */ 5694 if (pfmemalloc) 5695 noreclaim_flag = memalloc_noreclaim_save(); 5696 else 5697 memalloc_noreclaim_restore(noreclaim_flag); 5698 } 5699 } 5700 /* Handle the remaining sublist */ 5701 if (!list_empty(head)) 5702 __netif_receive_skb_list_core(head, pfmemalloc); 5703 /* Restore pflags */ 5704 if (pfmemalloc) 5705 memalloc_noreclaim_restore(noreclaim_flag); 5706 } 5707 5708 static int generic_xdp_install(struct net_device *dev, struct netdev_bpf *xdp) 5709 { 5710 struct bpf_prog *old = rtnl_dereference(dev->xdp_prog); 5711 struct bpf_prog *new = xdp->prog; 5712 int ret = 0; 5713 5714 switch (xdp->command) { 5715 case XDP_SETUP_PROG: 5716 rcu_assign_pointer(dev->xdp_prog, new); 5717 if (old) 5718 bpf_prog_put(old); 5719 5720 if (old && !new) { 5721 static_branch_dec(&generic_xdp_needed_key); 5722 } else if (new && !old) { 5723 static_branch_inc(&generic_xdp_needed_key); 5724 dev_disable_lro(dev); 5725 dev_disable_gro_hw(dev); 5726 } 5727 break; 5728 5729 default: 5730 ret = -EINVAL; 5731 break; 5732 } 5733 5734 return ret; 5735 } 5736 5737 static int netif_receive_skb_internal(struct sk_buff *skb) 5738 { 5739 int ret; 5740 5741 net_timestamp_check(READ_ONCE(netdev_tstamp_prequeue), skb); 5742 5743 if (skb_defer_rx_timestamp(skb)) 5744 return NET_RX_SUCCESS; 5745 5746 rcu_read_lock(); 5747 #ifdef CONFIG_RPS 5748 if (static_branch_unlikely(&rps_needed)) { 5749 struct rps_dev_flow voidflow, *rflow = &voidflow; 5750 int cpu = get_rps_cpu(skb->dev, skb, &rflow); 5751 5752 if (cpu >= 0) { 5753 ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail); 5754 rcu_read_unlock(); 5755 return ret; 5756 } 5757 } 5758 #endif 5759 ret = __netif_receive_skb(skb); 5760 rcu_read_unlock(); 5761 return ret; 5762 } 5763 5764 void netif_receive_skb_list_internal(struct list_head *head) 5765 { 5766 struct sk_buff *skb, *next; 5767 struct list_head sublist; 5768 5769 INIT_LIST_HEAD(&sublist); 5770 list_for_each_entry_safe(skb, next, head, list) { 5771 net_timestamp_check(READ_ONCE(netdev_tstamp_prequeue), skb); 5772 skb_list_del_init(skb); 5773 if (!skb_defer_rx_timestamp(skb)) 5774 list_add_tail(&skb->list, &sublist); 5775 } 5776 list_splice_init(&sublist, head); 5777 5778 rcu_read_lock(); 5779 #ifdef CONFIG_RPS 5780 if (static_branch_unlikely(&rps_needed)) { 5781 list_for_each_entry_safe(skb, next, head, list) { 5782 struct rps_dev_flow voidflow, *rflow = &voidflow; 5783 int cpu = get_rps_cpu(skb->dev, skb, &rflow); 5784 5785 if (cpu >= 0) { 5786 /* Will be handled, remove from list */ 5787 skb_list_del_init(skb); 5788 enqueue_to_backlog(skb, cpu, &rflow->last_qtail); 5789 } 5790 } 5791 } 5792 #endif 5793 __netif_receive_skb_list(head); 5794 rcu_read_unlock(); 5795 } 5796 5797 /** 5798 * netif_receive_skb - process receive buffer from network 5799 * @skb: buffer to process 5800 * 5801 * netif_receive_skb() is the main receive data processing function. 5802 * It always succeeds. The buffer may be dropped during processing 5803 * for congestion control or by the protocol layers. 5804 * 5805 * This function may only be called from softirq context and interrupts 5806 * should be enabled. 5807 * 5808 * Return values (usually ignored): 5809 * NET_RX_SUCCESS: no congestion 5810 * NET_RX_DROP: packet was dropped 5811 */ 5812 int netif_receive_skb(struct sk_buff *skb) 5813 { 5814 int ret; 5815 5816 trace_netif_receive_skb_entry(skb); 5817 5818 ret = netif_receive_skb_internal(skb); 5819 trace_netif_receive_skb_exit(ret); 5820 5821 return ret; 5822 } 5823 EXPORT_SYMBOL(netif_receive_skb); 5824 5825 /** 5826 * netif_receive_skb_list - process many receive buffers from network 5827 * @head: list of skbs to process. 5828 * 5829 * Since return value of netif_receive_skb() is normally ignored, and 5830 * wouldn't be meaningful for a list, this function returns void. 5831 * 5832 * This function may only be called from softirq context and interrupts 5833 * should be enabled. 5834 */ 5835 void netif_receive_skb_list(struct list_head *head) 5836 { 5837 struct sk_buff *skb; 5838 5839 if (list_empty(head)) 5840 return; 5841 if (trace_netif_receive_skb_list_entry_enabled()) { 5842 list_for_each_entry(skb, head, list) 5843 trace_netif_receive_skb_list_entry(skb); 5844 } 5845 netif_receive_skb_list_internal(head); 5846 trace_netif_receive_skb_list_exit(0); 5847 } 5848 EXPORT_SYMBOL(netif_receive_skb_list); 5849 5850 static DEFINE_PER_CPU(struct work_struct, flush_works); 5851 5852 /* Network device is going away, flush any packets still pending */ 5853 static void flush_backlog(struct work_struct *work) 5854 { 5855 struct sk_buff *skb, *tmp; 5856 struct softnet_data *sd; 5857 5858 local_bh_disable(); 5859 sd = this_cpu_ptr(&softnet_data); 5860 5861 rps_lock_irq_disable(sd); 5862 skb_queue_walk_safe(&sd->input_pkt_queue, skb, tmp) { 5863 if (skb->dev->reg_state == NETREG_UNREGISTERING) { 5864 __skb_unlink(skb, &sd->input_pkt_queue); 5865 dev_kfree_skb_irq(skb); 5866 input_queue_head_incr(sd); 5867 } 5868 } 5869 rps_unlock_irq_enable(sd); 5870 5871 skb_queue_walk_safe(&sd->process_queue, skb, tmp) { 5872 if (skb->dev->reg_state == NETREG_UNREGISTERING) { 5873 __skb_unlink(skb, &sd->process_queue); 5874 kfree_skb(skb); 5875 input_queue_head_incr(sd); 5876 } 5877 } 5878 local_bh_enable(); 5879 } 5880 5881 static bool flush_required(int cpu) 5882 { 5883 #if IS_ENABLED(CONFIG_RPS) 5884 struct softnet_data *sd = &per_cpu(softnet_data, cpu); 5885 bool do_flush; 5886 5887 rps_lock_irq_disable(sd); 5888 5889 /* as insertion into process_queue happens with the rps lock held, 5890 * process_queue access may race only with dequeue 5891 */ 5892 do_flush = !skb_queue_empty(&sd->input_pkt_queue) || 5893 !skb_queue_empty_lockless(&sd->process_queue); 5894 rps_unlock_irq_enable(sd); 5895 5896 return do_flush; 5897 #endif 5898 /* without RPS we can't safely check input_pkt_queue: during a 5899 * concurrent remote skb_queue_splice() we can detect as empty both 5900 * input_pkt_queue and process_queue even if the latter could end-up 5901 * containing a lot of packets. 5902 */ 5903 return true; 5904 } 5905 5906 static void flush_all_backlogs(void) 5907 { 5908 static cpumask_t flush_cpus; 5909 unsigned int cpu; 5910 5911 /* since we are under rtnl lock protection we can use static data 5912 * for the cpumask and avoid allocating on stack the possibly 5913 * large mask 5914 */ 5915 ASSERT_RTNL(); 5916 5917 cpus_read_lock(); 5918 5919 cpumask_clear(&flush_cpus); 5920 for_each_online_cpu(cpu) { 5921 if (flush_required(cpu)) { 5922 queue_work_on(cpu, system_highpri_wq, 5923 per_cpu_ptr(&flush_works, cpu)); 5924 cpumask_set_cpu(cpu, &flush_cpus); 5925 } 5926 } 5927 5928 /* we can have in flight packet[s] on the cpus we are not flushing, 5929 * synchronize_net() in unregister_netdevice_many() will take care of 5930 * them 5931 */ 5932 for_each_cpu(cpu, &flush_cpus) 5933 flush_work(per_cpu_ptr(&flush_works, cpu)); 5934 5935 cpus_read_unlock(); 5936 } 5937 5938 static void net_rps_send_ipi(struct softnet_data *remsd) 5939 { 5940 #ifdef CONFIG_RPS 5941 while (remsd) { 5942 struct softnet_data *next = remsd->rps_ipi_next; 5943 5944 if (cpu_online(remsd->cpu)) 5945 smp_call_function_single_async(remsd->cpu, &remsd->csd); 5946 remsd = next; 5947 } 5948 #endif 5949 } 5950 5951 /* 5952 * net_rps_action_and_irq_enable sends any pending IPI's for rps. 5953 * Note: called with local irq disabled, but exits with local irq enabled. 5954 */ 5955 static void net_rps_action_and_irq_enable(struct softnet_data *sd) 5956 { 5957 #ifdef CONFIG_RPS 5958 struct softnet_data *remsd = sd->rps_ipi_list; 5959 5960 if (remsd) { 5961 sd->rps_ipi_list = NULL; 5962 5963 local_irq_enable(); 5964 5965 /* Send pending IPI's to kick RPS processing on remote cpus. */ 5966 net_rps_send_ipi(remsd); 5967 } else 5968 #endif 5969 local_irq_enable(); 5970 } 5971 5972 static bool sd_has_rps_ipi_waiting(struct softnet_data *sd) 5973 { 5974 #ifdef CONFIG_RPS 5975 return sd->rps_ipi_list != NULL; 5976 #else 5977 return false; 5978 #endif 5979 } 5980 5981 static int process_backlog(struct napi_struct *napi, int quota) 5982 { 5983 struct softnet_data *sd = container_of(napi, struct softnet_data, backlog); 5984 bool again = true; 5985 int work = 0; 5986 5987 /* Check if we have pending ipi, its better to send them now, 5988 * not waiting net_rx_action() end. 5989 */ 5990 if (sd_has_rps_ipi_waiting(sd)) { 5991 local_irq_disable(); 5992 net_rps_action_and_irq_enable(sd); 5993 } 5994 5995 napi->weight = READ_ONCE(dev_rx_weight); 5996 while (again) { 5997 struct sk_buff *skb; 5998 5999 while ((skb = __skb_dequeue(&sd->process_queue))) { 6000 rcu_read_lock(); 6001 __netif_receive_skb(skb); 6002 rcu_read_unlock(); 6003 input_queue_head_incr(sd); 6004 if (++work >= quota) 6005 return work; 6006 6007 } 6008 6009 rps_lock_irq_disable(sd); 6010 if (skb_queue_empty(&sd->input_pkt_queue)) { 6011 /* 6012 * Inline a custom version of __napi_complete(). 6013 * only current cpu owns and manipulates this napi, 6014 * and NAPI_STATE_SCHED is the only possible flag set 6015 * on backlog. 6016 * We can use a plain write instead of clear_bit(), 6017 * and we dont need an smp_mb() memory barrier. 6018 */ 6019 napi->state = 0; 6020 again = false; 6021 } else { 6022 skb_queue_splice_tail_init(&sd->input_pkt_queue, 6023 &sd->process_queue); 6024 } 6025 rps_unlock_irq_enable(sd); 6026 } 6027 6028 return work; 6029 } 6030 6031 /** 6032 * __napi_schedule - schedule for receive 6033 * @n: entry to schedule 6034 * 6035 * The entry's receive function will be scheduled to run. 6036 * Consider using __napi_schedule_irqoff() if hard irqs are masked. 6037 */ 6038 void __napi_schedule(struct napi_struct *n) 6039 { 6040 unsigned long flags; 6041 6042 local_irq_save(flags); 6043 ____napi_schedule(this_cpu_ptr(&softnet_data), n); 6044 local_irq_restore(flags); 6045 } 6046 EXPORT_SYMBOL(__napi_schedule); 6047 6048 /** 6049 * napi_schedule_prep - check if napi can be scheduled 6050 * @n: napi context 6051 * 6052 * Test if NAPI routine is already running, and if not mark 6053 * it as running. This is used as a condition variable to 6054 * insure only one NAPI poll instance runs. We also make 6055 * sure there is no pending NAPI disable. 6056 */ 6057 bool napi_schedule_prep(struct napi_struct *n) 6058 { 6059 unsigned long new, val = READ_ONCE(n->state); 6060 6061 do { 6062 if (unlikely(val & NAPIF_STATE_DISABLE)) 6063 return false; 6064 new = val | NAPIF_STATE_SCHED; 6065 6066 /* Sets STATE_MISSED bit if STATE_SCHED was already set 6067 * This was suggested by Alexander Duyck, as compiler 6068 * emits better code than : 6069 * if (val & NAPIF_STATE_SCHED) 6070 * new |= NAPIF_STATE_MISSED; 6071 */ 6072 new |= (val & NAPIF_STATE_SCHED) / NAPIF_STATE_SCHED * 6073 NAPIF_STATE_MISSED; 6074 } while (!try_cmpxchg(&n->state, &val, new)); 6075 6076 return !(val & NAPIF_STATE_SCHED); 6077 } 6078 EXPORT_SYMBOL(napi_schedule_prep); 6079 6080 /** 6081 * __napi_schedule_irqoff - schedule for receive 6082 * @n: entry to schedule 6083 * 6084 * Variant of __napi_schedule() assuming hard irqs are masked. 6085 * 6086 * On PREEMPT_RT enabled kernels this maps to __napi_schedule() 6087 * because the interrupt disabled assumption might not be true 6088 * due to force-threaded interrupts and spinlock substitution. 6089 */ 6090 void __napi_schedule_irqoff(struct napi_struct *n) 6091 { 6092 if (!IS_ENABLED(CONFIG_PREEMPT_RT)) 6093 ____napi_schedule(this_cpu_ptr(&softnet_data), n); 6094 else 6095 __napi_schedule(n); 6096 } 6097 EXPORT_SYMBOL(__napi_schedule_irqoff); 6098 6099 bool napi_complete_done(struct napi_struct *n, int work_done) 6100 { 6101 unsigned long flags, val, new, timeout = 0; 6102 bool ret = true; 6103 6104 /* 6105 * 1) Don't let napi dequeue from the cpu poll list 6106 * just in case its running on a different cpu. 6107 * 2) If we are busy polling, do nothing here, we have 6108 * the guarantee we will be called later. 6109 */ 6110 if (unlikely(n->state & (NAPIF_STATE_NPSVC | 6111 NAPIF_STATE_IN_BUSY_POLL))) 6112 return false; 6113 6114 if (work_done) { 6115 if (n->gro_bitmask) 6116 timeout = READ_ONCE(n->dev->gro_flush_timeout); 6117 n->defer_hard_irqs_count = READ_ONCE(n->dev->napi_defer_hard_irqs); 6118 } 6119 if (n->defer_hard_irqs_count > 0) { 6120 n->defer_hard_irqs_count--; 6121 timeout = READ_ONCE(n->dev->gro_flush_timeout); 6122 if (timeout) 6123 ret = false; 6124 } 6125 if (n->gro_bitmask) { 6126 /* When the NAPI instance uses a timeout and keeps postponing 6127 * it, we need to bound somehow the time packets are kept in 6128 * the GRO layer 6129 */ 6130 napi_gro_flush(n, !!timeout); 6131 } 6132 6133 gro_normal_list(n); 6134 6135 if (unlikely(!list_empty(&n->poll_list))) { 6136 /* If n->poll_list is not empty, we need to mask irqs */ 6137 local_irq_save(flags); 6138 list_del_init(&n->poll_list); 6139 local_irq_restore(flags); 6140 } 6141 WRITE_ONCE(n->list_owner, -1); 6142 6143 val = READ_ONCE(n->state); 6144 do { 6145 WARN_ON_ONCE(!(val & NAPIF_STATE_SCHED)); 6146 6147 new = val & ~(NAPIF_STATE_MISSED | NAPIF_STATE_SCHED | 6148 NAPIF_STATE_SCHED_THREADED | 6149 NAPIF_STATE_PREFER_BUSY_POLL); 6150 6151 /* If STATE_MISSED was set, leave STATE_SCHED set, 6152 * because we will call napi->poll() one more time. 6153 * This C code was suggested by Alexander Duyck to help gcc. 6154 */ 6155 new |= (val & NAPIF_STATE_MISSED) / NAPIF_STATE_MISSED * 6156 NAPIF_STATE_SCHED; 6157 } while (!try_cmpxchg(&n->state, &val, new)); 6158 6159 if (unlikely(val & NAPIF_STATE_MISSED)) { 6160 __napi_schedule(n); 6161 return false; 6162 } 6163 6164 if (timeout) 6165 hrtimer_start(&n->timer, ns_to_ktime(timeout), 6166 HRTIMER_MODE_REL_PINNED); 6167 return ret; 6168 } 6169 EXPORT_SYMBOL(napi_complete_done); 6170 6171 /* must be called under rcu_read_lock(), as we dont take a reference */ 6172 static struct napi_struct *napi_by_id(unsigned int napi_id) 6173 { 6174 unsigned int hash = napi_id % HASH_SIZE(napi_hash); 6175 struct napi_struct *napi; 6176 6177 hlist_for_each_entry_rcu(napi, &napi_hash[hash], napi_hash_node) 6178 if (napi->napi_id == napi_id) 6179 return napi; 6180 6181 return NULL; 6182 } 6183 6184 #if defined(CONFIG_NET_RX_BUSY_POLL) 6185 6186 static void __busy_poll_stop(struct napi_struct *napi, bool skip_schedule) 6187 { 6188 if (!skip_schedule) { 6189 gro_normal_list(napi); 6190 __napi_schedule(napi); 6191 return; 6192 } 6193 6194 if (napi->gro_bitmask) { 6195 /* flush too old packets 6196 * If HZ < 1000, flush all packets. 6197 */ 6198 napi_gro_flush(napi, HZ >= 1000); 6199 } 6200 6201 gro_normal_list(napi); 6202 clear_bit(NAPI_STATE_SCHED, &napi->state); 6203 } 6204 6205 static void busy_poll_stop(struct napi_struct *napi, void *have_poll_lock, bool prefer_busy_poll, 6206 u16 budget) 6207 { 6208 bool skip_schedule = false; 6209 unsigned long timeout; 6210 int rc; 6211 6212 /* Busy polling means there is a high chance device driver hard irq 6213 * could not grab NAPI_STATE_SCHED, and that NAPI_STATE_MISSED was 6214 * set in napi_schedule_prep(). 6215 * Since we are about to call napi->poll() once more, we can safely 6216 * clear NAPI_STATE_MISSED. 6217 * 6218 * Note: x86 could use a single "lock and ..." instruction 6219 * to perform these two clear_bit() 6220 */ 6221 clear_bit(NAPI_STATE_MISSED, &napi->state); 6222 clear_bit(NAPI_STATE_IN_BUSY_POLL, &napi->state); 6223 6224 local_bh_disable(); 6225 6226 if (prefer_busy_poll) { 6227 napi->defer_hard_irqs_count = READ_ONCE(napi->dev->napi_defer_hard_irqs); 6228 timeout = READ_ONCE(napi->dev->gro_flush_timeout); 6229 if (napi->defer_hard_irqs_count && timeout) { 6230 hrtimer_start(&napi->timer, ns_to_ktime(timeout), HRTIMER_MODE_REL_PINNED); 6231 skip_schedule = true; 6232 } 6233 } 6234 6235 /* All we really want here is to re-enable device interrupts. 6236 * Ideally, a new ndo_busy_poll_stop() could avoid another round. 6237 */ 6238 rc = napi->poll(napi, budget); 6239 /* We can't gro_normal_list() here, because napi->poll() might have 6240 * rearmed the napi (napi_complete_done()) in which case it could 6241 * already be running on another CPU. 6242 */ 6243 trace_napi_poll(napi, rc, budget); 6244 netpoll_poll_unlock(have_poll_lock); 6245 if (rc == budget) 6246 __busy_poll_stop(napi, skip_schedule); 6247 local_bh_enable(); 6248 } 6249 6250 void napi_busy_loop(unsigned int napi_id, 6251 bool (*loop_end)(void *, unsigned long), 6252 void *loop_end_arg, bool prefer_busy_poll, u16 budget) 6253 { 6254 unsigned long start_time = loop_end ? busy_loop_current_time() : 0; 6255 int (*napi_poll)(struct napi_struct *napi, int budget); 6256 void *have_poll_lock = NULL; 6257 struct napi_struct *napi; 6258 6259 restart: 6260 napi_poll = NULL; 6261 6262 rcu_read_lock(); 6263 6264 napi = napi_by_id(napi_id); 6265 if (!napi) 6266 goto out; 6267 6268 if (!IS_ENABLED(CONFIG_PREEMPT_RT)) 6269 preempt_disable(); 6270 for (;;) { 6271 int work = 0; 6272 6273 local_bh_disable(); 6274 if (!napi_poll) { 6275 unsigned long val = READ_ONCE(napi->state); 6276 6277 /* If multiple threads are competing for this napi, 6278 * we avoid dirtying napi->state as much as we can. 6279 */ 6280 if (val & (NAPIF_STATE_DISABLE | NAPIF_STATE_SCHED | 6281 NAPIF_STATE_IN_BUSY_POLL)) { 6282 if (prefer_busy_poll) 6283 set_bit(NAPI_STATE_PREFER_BUSY_POLL, &napi->state); 6284 goto count; 6285 } 6286 if (cmpxchg(&napi->state, val, 6287 val | NAPIF_STATE_IN_BUSY_POLL | 6288 NAPIF_STATE_SCHED) != val) { 6289 if (prefer_busy_poll) 6290 set_bit(NAPI_STATE_PREFER_BUSY_POLL, &napi->state); 6291 goto count; 6292 } 6293 have_poll_lock = netpoll_poll_lock(napi); 6294 napi_poll = napi->poll; 6295 } 6296 work = napi_poll(napi, budget); 6297 trace_napi_poll(napi, work, budget); 6298 gro_normal_list(napi); 6299 count: 6300 if (work > 0) 6301 __NET_ADD_STATS(dev_net(napi->dev), 6302 LINUX_MIB_BUSYPOLLRXPACKETS, work); 6303 local_bh_enable(); 6304 6305 if (!loop_end || loop_end(loop_end_arg, start_time)) 6306 break; 6307 6308 if (unlikely(need_resched())) { 6309 if (napi_poll) 6310 busy_poll_stop(napi, have_poll_lock, prefer_busy_poll, budget); 6311 if (!IS_ENABLED(CONFIG_PREEMPT_RT)) 6312 preempt_enable(); 6313 rcu_read_unlock(); 6314 cond_resched(); 6315 if (loop_end(loop_end_arg, start_time)) 6316 return; 6317 goto restart; 6318 } 6319 cpu_relax(); 6320 } 6321 if (napi_poll) 6322 busy_poll_stop(napi, have_poll_lock, prefer_busy_poll, budget); 6323 if (!IS_ENABLED(CONFIG_PREEMPT_RT)) 6324 preempt_enable(); 6325 out: 6326 rcu_read_unlock(); 6327 } 6328 EXPORT_SYMBOL(napi_busy_loop); 6329 6330 #endif /* CONFIG_NET_RX_BUSY_POLL */ 6331 6332 static void napi_hash_add(struct napi_struct *napi) 6333 { 6334 if (test_bit(NAPI_STATE_NO_BUSY_POLL, &napi->state)) 6335 return; 6336 6337 spin_lock(&napi_hash_lock); 6338 6339 /* 0..NR_CPUS range is reserved for sender_cpu use */ 6340 do { 6341 if (unlikely(++napi_gen_id < MIN_NAPI_ID)) 6342 napi_gen_id = MIN_NAPI_ID; 6343 } while (napi_by_id(napi_gen_id)); 6344 napi->napi_id = napi_gen_id; 6345 6346 hlist_add_head_rcu(&napi->napi_hash_node, 6347 &napi_hash[napi->napi_id % HASH_SIZE(napi_hash)]); 6348 6349 spin_unlock(&napi_hash_lock); 6350 } 6351 6352 /* Warning : caller is responsible to make sure rcu grace period 6353 * is respected before freeing memory containing @napi 6354 */ 6355 static void napi_hash_del(struct napi_struct *napi) 6356 { 6357 spin_lock(&napi_hash_lock); 6358 6359 hlist_del_init_rcu(&napi->napi_hash_node); 6360 6361 spin_unlock(&napi_hash_lock); 6362 } 6363 6364 static enum hrtimer_restart napi_watchdog(struct hrtimer *timer) 6365 { 6366 struct napi_struct *napi; 6367 6368 napi = container_of(timer, struct napi_struct, timer); 6369 6370 /* Note : we use a relaxed variant of napi_schedule_prep() not setting 6371 * NAPI_STATE_MISSED, since we do not react to a device IRQ. 6372 */ 6373 if (!napi_disable_pending(napi) && 6374 !test_and_set_bit(NAPI_STATE_SCHED, &napi->state)) { 6375 clear_bit(NAPI_STATE_PREFER_BUSY_POLL, &napi->state); 6376 __napi_schedule_irqoff(napi); 6377 } 6378 6379 return HRTIMER_NORESTART; 6380 } 6381 6382 static void init_gro_hash(struct napi_struct *napi) 6383 { 6384 int i; 6385 6386 for (i = 0; i < GRO_HASH_BUCKETS; i++) { 6387 INIT_LIST_HEAD(&napi->gro_hash[i].list); 6388 napi->gro_hash[i].count = 0; 6389 } 6390 napi->gro_bitmask = 0; 6391 } 6392 6393 int dev_set_threaded(struct net_device *dev, bool threaded) 6394 { 6395 struct napi_struct *napi; 6396 int err = 0; 6397 6398 if (dev->threaded == threaded) 6399 return 0; 6400 6401 if (threaded) { 6402 list_for_each_entry(napi, &dev->napi_list, dev_list) { 6403 if (!napi->thread) { 6404 err = napi_kthread_create(napi); 6405 if (err) { 6406 threaded = false; 6407 break; 6408 } 6409 } 6410 } 6411 } 6412 6413 dev->threaded = threaded; 6414 6415 /* Make sure kthread is created before THREADED bit 6416 * is set. 6417 */ 6418 smp_mb__before_atomic(); 6419 6420 /* Setting/unsetting threaded mode on a napi might not immediately 6421 * take effect, if the current napi instance is actively being 6422 * polled. In this case, the switch between threaded mode and 6423 * softirq mode will happen in the next round of napi_schedule(). 6424 * This should not cause hiccups/stalls to the live traffic. 6425 */ 6426 list_for_each_entry(napi, &dev->napi_list, dev_list) 6427 assign_bit(NAPI_STATE_THREADED, &napi->state, threaded); 6428 6429 return err; 6430 } 6431 EXPORT_SYMBOL(dev_set_threaded); 6432 6433 void netif_napi_add_weight(struct net_device *dev, struct napi_struct *napi, 6434 int (*poll)(struct napi_struct *, int), int weight) 6435 { 6436 if (WARN_ON(test_and_set_bit(NAPI_STATE_LISTED, &napi->state))) 6437 return; 6438 6439 INIT_LIST_HEAD(&napi->poll_list); 6440 INIT_HLIST_NODE(&napi->napi_hash_node); 6441 hrtimer_init(&napi->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_PINNED); 6442 napi->timer.function = napi_watchdog; 6443 init_gro_hash(napi); 6444 napi->skb = NULL; 6445 INIT_LIST_HEAD(&napi->rx_list); 6446 napi->rx_count = 0; 6447 napi->poll = poll; 6448 if (weight > NAPI_POLL_WEIGHT) 6449 netdev_err_once(dev, "%s() called with weight %d\n", __func__, 6450 weight); 6451 napi->weight = weight; 6452 napi->dev = dev; 6453 #ifdef CONFIG_NETPOLL 6454 napi->poll_owner = -1; 6455 #endif 6456 napi->list_owner = -1; 6457 set_bit(NAPI_STATE_SCHED, &napi->state); 6458 set_bit(NAPI_STATE_NPSVC, &napi->state); 6459 list_add_rcu(&napi->dev_list, &dev->napi_list); 6460 napi_hash_add(napi); 6461 napi_get_frags_check(napi); 6462 /* Create kthread for this napi if dev->threaded is set. 6463 * Clear dev->threaded if kthread creation failed so that 6464 * threaded mode will not be enabled in napi_enable(). 6465 */ 6466 if (dev->threaded && napi_kthread_create(napi)) 6467 dev->threaded = 0; 6468 } 6469 EXPORT_SYMBOL(netif_napi_add_weight); 6470 6471 void napi_disable(struct napi_struct *n) 6472 { 6473 unsigned long val, new; 6474 6475 might_sleep(); 6476 set_bit(NAPI_STATE_DISABLE, &n->state); 6477 6478 val = READ_ONCE(n->state); 6479 do { 6480 while (val & (NAPIF_STATE_SCHED | NAPIF_STATE_NPSVC)) { 6481 usleep_range(20, 200); 6482 val = READ_ONCE(n->state); 6483 } 6484 6485 new = val | NAPIF_STATE_SCHED | NAPIF_STATE_NPSVC; 6486 new &= ~(NAPIF_STATE_THREADED | NAPIF_STATE_PREFER_BUSY_POLL); 6487 } while (!try_cmpxchg(&n->state, &val, new)); 6488 6489 hrtimer_cancel(&n->timer); 6490 6491 clear_bit(NAPI_STATE_DISABLE, &n->state); 6492 } 6493 EXPORT_SYMBOL(napi_disable); 6494 6495 /** 6496 * napi_enable - enable NAPI scheduling 6497 * @n: NAPI context 6498 * 6499 * Resume NAPI from being scheduled on this context. 6500 * Must be paired with napi_disable. 6501 */ 6502 void napi_enable(struct napi_struct *n) 6503 { 6504 unsigned long new, val = READ_ONCE(n->state); 6505 6506 do { 6507 BUG_ON(!test_bit(NAPI_STATE_SCHED, &val)); 6508 6509 new = val & ~(NAPIF_STATE_SCHED | NAPIF_STATE_NPSVC); 6510 if (n->dev->threaded && n->thread) 6511 new |= NAPIF_STATE_THREADED; 6512 } while (!try_cmpxchg(&n->state, &val, new)); 6513 } 6514 EXPORT_SYMBOL(napi_enable); 6515 6516 static void flush_gro_hash(struct napi_struct *napi) 6517 { 6518 int i; 6519 6520 for (i = 0; i < GRO_HASH_BUCKETS; i++) { 6521 struct sk_buff *skb, *n; 6522 6523 list_for_each_entry_safe(skb, n, &napi->gro_hash[i].list, list) 6524 kfree_skb(skb); 6525 napi->gro_hash[i].count = 0; 6526 } 6527 } 6528 6529 /* Must be called in process context */ 6530 void __netif_napi_del(struct napi_struct *napi) 6531 { 6532 if (!test_and_clear_bit(NAPI_STATE_LISTED, &napi->state)) 6533 return; 6534 6535 napi_hash_del(napi); 6536 list_del_rcu(&napi->dev_list); 6537 napi_free_frags(napi); 6538 6539 flush_gro_hash(napi); 6540 napi->gro_bitmask = 0; 6541 6542 if (napi->thread) { 6543 kthread_stop(napi->thread); 6544 napi->thread = NULL; 6545 } 6546 } 6547 EXPORT_SYMBOL(__netif_napi_del); 6548 6549 static int __napi_poll(struct napi_struct *n, bool *repoll) 6550 { 6551 int work, weight; 6552 6553 weight = n->weight; 6554 6555 /* This NAPI_STATE_SCHED test is for avoiding a race 6556 * with netpoll's poll_napi(). Only the entity which 6557 * obtains the lock and sees NAPI_STATE_SCHED set will 6558 * actually make the ->poll() call. Therefore we avoid 6559 * accidentally calling ->poll() when NAPI is not scheduled. 6560 */ 6561 work = 0; 6562 if (test_bit(NAPI_STATE_SCHED, &n->state)) { 6563 work = n->poll(n, weight); 6564 trace_napi_poll(n, work, weight); 6565 } 6566 6567 if (unlikely(work > weight)) 6568 netdev_err_once(n->dev, "NAPI poll function %pS returned %d, exceeding its budget of %d.\n", 6569 n->poll, work, weight); 6570 6571 if (likely(work < weight)) 6572 return work; 6573 6574 /* Drivers must not modify the NAPI state if they 6575 * consume the entire weight. In such cases this code 6576 * still "owns" the NAPI instance and therefore can 6577 * move the instance around on the list at-will. 6578 */ 6579 if (unlikely(napi_disable_pending(n))) { 6580 napi_complete(n); 6581 return work; 6582 } 6583 6584 /* The NAPI context has more processing work, but busy-polling 6585 * is preferred. Exit early. 6586 */ 6587 if (napi_prefer_busy_poll(n)) { 6588 if (napi_complete_done(n, work)) { 6589 /* If timeout is not set, we need to make sure 6590 * that the NAPI is re-scheduled. 6591 */ 6592 napi_schedule(n); 6593 } 6594 return work; 6595 } 6596 6597 if (n->gro_bitmask) { 6598 /* flush too old packets 6599 * If HZ < 1000, flush all packets. 6600 */ 6601 napi_gro_flush(n, HZ >= 1000); 6602 } 6603 6604 gro_normal_list(n); 6605 6606 /* Some drivers may have called napi_schedule 6607 * prior to exhausting their budget. 6608 */ 6609 if (unlikely(!list_empty(&n->poll_list))) { 6610 pr_warn_once("%s: Budget exhausted after napi rescheduled\n", 6611 n->dev ? n->dev->name : "backlog"); 6612 return work; 6613 } 6614 6615 *repoll = true; 6616 6617 return work; 6618 } 6619 6620 static int napi_poll(struct napi_struct *n, struct list_head *repoll) 6621 { 6622 bool do_repoll = false; 6623 void *have; 6624 int work; 6625 6626 list_del_init(&n->poll_list); 6627 6628 have = netpoll_poll_lock(n); 6629 6630 work = __napi_poll(n, &do_repoll); 6631 6632 if (do_repoll) 6633 list_add_tail(&n->poll_list, repoll); 6634 6635 netpoll_poll_unlock(have); 6636 6637 return work; 6638 } 6639 6640 static int napi_thread_wait(struct napi_struct *napi) 6641 { 6642 bool woken = false; 6643 6644 set_current_state(TASK_INTERRUPTIBLE); 6645 6646 while (!kthread_should_stop()) { 6647 /* Testing SCHED_THREADED bit here to make sure the current 6648 * kthread owns this napi and could poll on this napi. 6649 * Testing SCHED bit is not enough because SCHED bit might be 6650 * set by some other busy poll thread or by napi_disable(). 6651 */ 6652 if (test_bit(NAPI_STATE_SCHED_THREADED, &napi->state) || woken) { 6653 WARN_ON(!list_empty(&napi->poll_list)); 6654 __set_current_state(TASK_RUNNING); 6655 return 0; 6656 } 6657 6658 schedule(); 6659 /* woken being true indicates this thread owns this napi. */ 6660 woken = true; 6661 set_current_state(TASK_INTERRUPTIBLE); 6662 } 6663 __set_current_state(TASK_RUNNING); 6664 6665 return -1; 6666 } 6667 6668 static void skb_defer_free_flush(struct softnet_data *sd) 6669 { 6670 struct sk_buff *skb, *next; 6671 6672 /* Paired with WRITE_ONCE() in skb_attempt_defer_free() */ 6673 if (!READ_ONCE(sd->defer_list)) 6674 return; 6675 6676 spin_lock(&sd->defer_lock); 6677 skb = sd->defer_list; 6678 sd->defer_list = NULL; 6679 sd->defer_count = 0; 6680 spin_unlock(&sd->defer_lock); 6681 6682 while (skb != NULL) { 6683 next = skb->next; 6684 napi_consume_skb(skb, 1); 6685 skb = next; 6686 } 6687 } 6688 6689 static int napi_threaded_poll(void *data) 6690 { 6691 struct napi_struct *napi = data; 6692 struct softnet_data *sd; 6693 void *have; 6694 6695 while (!napi_thread_wait(napi)) { 6696 unsigned long last_qs = jiffies; 6697 6698 for (;;) { 6699 bool repoll = false; 6700 6701 local_bh_disable(); 6702 sd = this_cpu_ptr(&softnet_data); 6703 sd->in_napi_threaded_poll = true; 6704 6705 have = netpoll_poll_lock(napi); 6706 __napi_poll(napi, &repoll); 6707 netpoll_poll_unlock(have); 6708 6709 sd->in_napi_threaded_poll = false; 6710 barrier(); 6711 6712 if (sd_has_rps_ipi_waiting(sd)) { 6713 local_irq_disable(); 6714 net_rps_action_and_irq_enable(sd); 6715 } 6716 skb_defer_free_flush(sd); 6717 local_bh_enable(); 6718 6719 if (!repoll) 6720 break; 6721 6722 rcu_softirq_qs_periodic(last_qs); 6723 cond_resched(); 6724 } 6725 } 6726 return 0; 6727 } 6728 6729 static __latent_entropy void net_rx_action(struct softirq_action *h) 6730 { 6731 struct softnet_data *sd = this_cpu_ptr(&softnet_data); 6732 unsigned long time_limit = jiffies + 6733 usecs_to_jiffies(READ_ONCE(netdev_budget_usecs)); 6734 int budget = READ_ONCE(netdev_budget); 6735 LIST_HEAD(list); 6736 LIST_HEAD(repoll); 6737 6738 start: 6739 sd->in_net_rx_action = true; 6740 local_irq_disable(); 6741 list_splice_init(&sd->poll_list, &list); 6742 local_irq_enable(); 6743 6744 for (;;) { 6745 struct napi_struct *n; 6746 6747 skb_defer_free_flush(sd); 6748 6749 if (list_empty(&list)) { 6750 if (list_empty(&repoll)) { 6751 sd->in_net_rx_action = false; 6752 barrier(); 6753 /* We need to check if ____napi_schedule() 6754 * had refilled poll_list while 6755 * sd->in_net_rx_action was true. 6756 */ 6757 if (!list_empty(&sd->poll_list)) 6758 goto start; 6759 if (!sd_has_rps_ipi_waiting(sd)) 6760 goto end; 6761 } 6762 break; 6763 } 6764 6765 n = list_first_entry(&list, struct napi_struct, poll_list); 6766 budget -= napi_poll(n, &repoll); 6767 6768 /* If softirq window is exhausted then punt. 6769 * Allow this to run for 2 jiffies since which will allow 6770 * an average latency of 1.5/HZ. 6771 */ 6772 if (unlikely(budget <= 0 || 6773 time_after_eq(jiffies, time_limit))) { 6774 sd->time_squeeze++; 6775 break; 6776 } 6777 } 6778 6779 local_irq_disable(); 6780 6781 list_splice_tail_init(&sd->poll_list, &list); 6782 list_splice_tail(&repoll, &list); 6783 list_splice(&list, &sd->poll_list); 6784 if (!list_empty(&sd->poll_list)) 6785 __raise_softirq_irqoff(NET_RX_SOFTIRQ); 6786 else 6787 sd->in_net_rx_action = false; 6788 6789 net_rps_action_and_irq_enable(sd); 6790 end:; 6791 } 6792 6793 struct netdev_adjacent { 6794 struct net_device *dev; 6795 netdevice_tracker dev_tracker; 6796 6797 /* upper master flag, there can only be one master device per list */ 6798 bool master; 6799 6800 /* lookup ignore flag */ 6801 bool ignore; 6802 6803 /* counter for the number of times this device was added to us */ 6804 u16 ref_nr; 6805 6806 /* private field for the users */ 6807 void *private; 6808 6809 struct list_head list; 6810 struct rcu_head rcu; 6811 }; 6812 6813 static struct netdev_adjacent *__netdev_find_adj(struct net_device *adj_dev, 6814 struct list_head *adj_list) 6815 { 6816 struct netdev_adjacent *adj; 6817 6818 list_for_each_entry(adj, adj_list, list) { 6819 if (adj->dev == adj_dev) 6820 return adj; 6821 } 6822 return NULL; 6823 } 6824 6825 static int ____netdev_has_upper_dev(struct net_device *upper_dev, 6826 struct netdev_nested_priv *priv) 6827 { 6828 struct net_device *dev = (struct net_device *)priv->data; 6829 6830 return upper_dev == dev; 6831 } 6832 6833 /** 6834 * netdev_has_upper_dev - Check if device is linked to an upper device 6835 * @dev: device 6836 * @upper_dev: upper device to check 6837 * 6838 * Find out if a device is linked to specified upper device and return true 6839 * in case it is. Note that this checks only immediate upper device, 6840 * not through a complete stack of devices. The caller must hold the RTNL lock. 6841 */ 6842 bool netdev_has_upper_dev(struct net_device *dev, 6843 struct net_device *upper_dev) 6844 { 6845 struct netdev_nested_priv priv = { 6846 .data = (void *)upper_dev, 6847 }; 6848 6849 ASSERT_RTNL(); 6850 6851 return netdev_walk_all_upper_dev_rcu(dev, ____netdev_has_upper_dev, 6852 &priv); 6853 } 6854 EXPORT_SYMBOL(netdev_has_upper_dev); 6855 6856 /** 6857 * netdev_has_upper_dev_all_rcu - Check if device is linked to an upper device 6858 * @dev: device 6859 * @upper_dev: upper device to check 6860 * 6861 * Find out if a device is linked to specified upper device and return true 6862 * in case it is. Note that this checks the entire upper device chain. 6863 * The caller must hold rcu lock. 6864 */ 6865 6866 bool netdev_has_upper_dev_all_rcu(struct net_device *dev, 6867 struct net_device *upper_dev) 6868 { 6869 struct netdev_nested_priv priv = { 6870 .data = (void *)upper_dev, 6871 }; 6872 6873 return !!netdev_walk_all_upper_dev_rcu(dev, ____netdev_has_upper_dev, 6874 &priv); 6875 } 6876 EXPORT_SYMBOL(netdev_has_upper_dev_all_rcu); 6877 6878 /** 6879 * netdev_has_any_upper_dev - Check if device is linked to some device 6880 * @dev: device 6881 * 6882 * Find out if a device is linked to an upper device and return true in case 6883 * it is. The caller must hold the RTNL lock. 6884 */ 6885 bool netdev_has_any_upper_dev(struct net_device *dev) 6886 { 6887 ASSERT_RTNL(); 6888 6889 return !list_empty(&dev->adj_list.upper); 6890 } 6891 EXPORT_SYMBOL(netdev_has_any_upper_dev); 6892 6893 /** 6894 * netdev_master_upper_dev_get - Get master upper device 6895 * @dev: device 6896 * 6897 * Find a master upper device and return pointer to it or NULL in case 6898 * it's not there. The caller must hold the RTNL lock. 6899 */ 6900 struct net_device *netdev_master_upper_dev_get(struct net_device *dev) 6901 { 6902 struct netdev_adjacent *upper; 6903 6904 ASSERT_RTNL(); 6905 6906 if (list_empty(&dev->adj_list.upper)) 6907 return NULL; 6908 6909 upper = list_first_entry(&dev->adj_list.upper, 6910 struct netdev_adjacent, list); 6911 if (likely(upper->master)) 6912 return upper->dev; 6913 return NULL; 6914 } 6915 EXPORT_SYMBOL(netdev_master_upper_dev_get); 6916 6917 static struct net_device *__netdev_master_upper_dev_get(struct net_device *dev) 6918 { 6919 struct netdev_adjacent *upper; 6920 6921 ASSERT_RTNL(); 6922 6923 if (list_empty(&dev->adj_list.upper)) 6924 return NULL; 6925 6926 upper = list_first_entry(&dev->adj_list.upper, 6927 struct netdev_adjacent, list); 6928 if (likely(upper->master) && !upper->ignore) 6929 return upper->dev; 6930 return NULL; 6931 } 6932 6933 /** 6934 * netdev_has_any_lower_dev - Check if device is linked to some device 6935 * @dev: device 6936 * 6937 * Find out if a device is linked to a lower device and return true in case 6938 * it is. The caller must hold the RTNL lock. 6939 */ 6940 static bool netdev_has_any_lower_dev(struct net_device *dev) 6941 { 6942 ASSERT_RTNL(); 6943 6944 return !list_empty(&dev->adj_list.lower); 6945 } 6946 6947 void *netdev_adjacent_get_private(struct list_head *adj_list) 6948 { 6949 struct netdev_adjacent *adj; 6950 6951 adj = list_entry(adj_list, struct netdev_adjacent, list); 6952 6953 return adj->private; 6954 } 6955 EXPORT_SYMBOL(netdev_adjacent_get_private); 6956 6957 /** 6958 * netdev_upper_get_next_dev_rcu - Get the next dev from upper list 6959 * @dev: device 6960 * @iter: list_head ** of the current position 6961 * 6962 * Gets the next device from the dev's upper list, starting from iter 6963 * position. The caller must hold RCU read lock. 6964 */ 6965 struct net_device *netdev_upper_get_next_dev_rcu(struct net_device *dev, 6966 struct list_head **iter) 6967 { 6968 struct netdev_adjacent *upper; 6969 6970 WARN_ON_ONCE(!rcu_read_lock_held() && !lockdep_rtnl_is_held()); 6971 6972 upper = list_entry_rcu((*iter)->next, struct netdev_adjacent, list); 6973 6974 if (&upper->list == &dev->adj_list.upper) 6975 return NULL; 6976 6977 *iter = &upper->list; 6978 6979 return upper->dev; 6980 } 6981 EXPORT_SYMBOL(netdev_upper_get_next_dev_rcu); 6982 6983 static struct net_device *__netdev_next_upper_dev(struct net_device *dev, 6984 struct list_head **iter, 6985 bool *ignore) 6986 { 6987 struct netdev_adjacent *upper; 6988 6989 upper = list_entry((*iter)->next, struct netdev_adjacent, list); 6990 6991 if (&upper->list == &dev->adj_list.upper) 6992 return NULL; 6993 6994 *iter = &upper->list; 6995 *ignore = upper->ignore; 6996 6997 return upper->dev; 6998 } 6999 7000 static struct net_device *netdev_next_upper_dev_rcu(struct net_device *dev, 7001 struct list_head **iter) 7002 { 7003 struct netdev_adjacent *upper; 7004 7005 WARN_ON_ONCE(!rcu_read_lock_held() && !lockdep_rtnl_is_held()); 7006 7007 upper = list_entry_rcu((*iter)->next, struct netdev_adjacent, list); 7008 7009 if (&upper->list == &dev->adj_list.upper) 7010 return NULL; 7011 7012 *iter = &upper->list; 7013 7014 return upper->dev; 7015 } 7016 7017 static int __netdev_walk_all_upper_dev(struct net_device *dev, 7018 int (*fn)(struct net_device *dev, 7019 struct netdev_nested_priv *priv), 7020 struct netdev_nested_priv *priv) 7021 { 7022 struct net_device *udev, *next, *now, *dev_stack[MAX_NEST_DEV + 1]; 7023 struct list_head *niter, *iter, *iter_stack[MAX_NEST_DEV + 1]; 7024 int ret, cur = 0; 7025 bool ignore; 7026 7027 now = dev; 7028 iter = &dev->adj_list.upper; 7029 7030 while (1) { 7031 if (now != dev) { 7032 ret = fn(now, priv); 7033 if (ret) 7034 return ret; 7035 } 7036 7037 next = NULL; 7038 while (1) { 7039 udev = __netdev_next_upper_dev(now, &iter, &ignore); 7040 if (!udev) 7041 break; 7042 if (ignore) 7043 continue; 7044 7045 next = udev; 7046 niter = &udev->adj_list.upper; 7047 dev_stack[cur] = now; 7048 iter_stack[cur++] = iter; 7049 break; 7050 } 7051 7052 if (!next) { 7053 if (!cur) 7054 return 0; 7055 next = dev_stack[--cur]; 7056 niter = iter_stack[cur]; 7057 } 7058 7059 now = next; 7060 iter = niter; 7061 } 7062 7063 return 0; 7064 } 7065 7066 int netdev_walk_all_upper_dev_rcu(struct net_device *dev, 7067 int (*fn)(struct net_device *dev, 7068 struct netdev_nested_priv *priv), 7069 struct netdev_nested_priv *priv) 7070 { 7071 struct net_device *udev, *next, *now, *dev_stack[MAX_NEST_DEV + 1]; 7072 struct list_head *niter, *iter, *iter_stack[MAX_NEST_DEV + 1]; 7073 int ret, cur = 0; 7074 7075 now = dev; 7076 iter = &dev->adj_list.upper; 7077 7078 while (1) { 7079 if (now != dev) { 7080 ret = fn(now, priv); 7081 if (ret) 7082 return ret; 7083 } 7084 7085 next = NULL; 7086 while (1) { 7087 udev = netdev_next_upper_dev_rcu(now, &iter); 7088 if (!udev) 7089 break; 7090 7091 next = udev; 7092 niter = &udev->adj_list.upper; 7093 dev_stack[cur] = now; 7094 iter_stack[cur++] = iter; 7095 break; 7096 } 7097 7098 if (!next) { 7099 if (!cur) 7100 return 0; 7101 next = dev_stack[--cur]; 7102 niter = iter_stack[cur]; 7103 } 7104 7105 now = next; 7106 iter = niter; 7107 } 7108 7109 return 0; 7110 } 7111 EXPORT_SYMBOL_GPL(netdev_walk_all_upper_dev_rcu); 7112 7113 static bool __netdev_has_upper_dev(struct net_device *dev, 7114 struct net_device *upper_dev) 7115 { 7116 struct netdev_nested_priv priv = { 7117 .flags = 0, 7118 .data = (void *)upper_dev, 7119 }; 7120 7121 ASSERT_RTNL(); 7122 7123 return __netdev_walk_all_upper_dev(dev, ____netdev_has_upper_dev, 7124 &priv); 7125 } 7126 7127 /** 7128 * netdev_lower_get_next_private - Get the next ->private from the 7129 * lower neighbour list 7130 * @dev: device 7131 * @iter: list_head ** of the current position 7132 * 7133 * Gets the next netdev_adjacent->private from the dev's lower neighbour 7134 * list, starting from iter position. The caller must hold either hold the 7135 * RTNL lock or its own locking that guarantees that the neighbour lower 7136 * list will remain unchanged. 7137 */ 7138 void *netdev_lower_get_next_private(struct net_device *dev, 7139 struct list_head **iter) 7140 { 7141 struct netdev_adjacent *lower; 7142 7143 lower = list_entry(*iter, struct netdev_adjacent, list); 7144 7145 if (&lower->list == &dev->adj_list.lower) 7146 return NULL; 7147 7148 *iter = lower->list.next; 7149 7150 return lower->private; 7151 } 7152 EXPORT_SYMBOL(netdev_lower_get_next_private); 7153 7154 /** 7155 * netdev_lower_get_next_private_rcu - Get the next ->private from the 7156 * lower neighbour list, RCU 7157 * variant 7158 * @dev: device 7159 * @iter: list_head ** of the current position 7160 * 7161 * Gets the next netdev_adjacent->private from the dev's lower neighbour 7162 * list, starting from iter position. The caller must hold RCU read lock. 7163 */ 7164 void *netdev_lower_get_next_private_rcu(struct net_device *dev, 7165 struct list_head **iter) 7166 { 7167 struct netdev_adjacent *lower; 7168 7169 WARN_ON_ONCE(!rcu_read_lock_held() && !rcu_read_lock_bh_held()); 7170 7171 lower = list_entry_rcu((*iter)->next, struct netdev_adjacent, list); 7172 7173 if (&lower->list == &dev->adj_list.lower) 7174 return NULL; 7175 7176 *iter = &lower->list; 7177 7178 return lower->private; 7179 } 7180 EXPORT_SYMBOL(netdev_lower_get_next_private_rcu); 7181 7182 /** 7183 * netdev_lower_get_next - Get the next device from the lower neighbour 7184 * list 7185 * @dev: device 7186 * @iter: list_head ** of the current position 7187 * 7188 * Gets the next netdev_adjacent from the dev's lower neighbour 7189 * list, starting from iter position. The caller must hold RTNL lock or 7190 * its own locking that guarantees that the neighbour lower 7191 * list will remain unchanged. 7192 */ 7193 void *netdev_lower_get_next(struct net_device *dev, struct list_head **iter) 7194 { 7195 struct netdev_adjacent *lower; 7196 7197 lower = list_entry(*iter, struct netdev_adjacent, list); 7198 7199 if (&lower->list == &dev->adj_list.lower) 7200 return NULL; 7201 7202 *iter = lower->list.next; 7203 7204 return lower->dev; 7205 } 7206 EXPORT_SYMBOL(netdev_lower_get_next); 7207 7208 static struct net_device *netdev_next_lower_dev(struct net_device *dev, 7209 struct list_head **iter) 7210 { 7211 struct netdev_adjacent *lower; 7212 7213 lower = list_entry((*iter)->next, struct netdev_adjacent, list); 7214 7215 if (&lower->list == &dev->adj_list.lower) 7216 return NULL; 7217 7218 *iter = &lower->list; 7219 7220 return lower->dev; 7221 } 7222 7223 static struct net_device *__netdev_next_lower_dev(struct net_device *dev, 7224 struct list_head **iter, 7225 bool *ignore) 7226 { 7227 struct netdev_adjacent *lower; 7228 7229 lower = list_entry((*iter)->next, struct netdev_adjacent, list); 7230 7231 if (&lower->list == &dev->adj_list.lower) 7232 return NULL; 7233 7234 *iter = &lower->list; 7235 *ignore = lower->ignore; 7236 7237 return lower->dev; 7238 } 7239 7240 int netdev_walk_all_lower_dev(struct net_device *dev, 7241 int (*fn)(struct net_device *dev, 7242 struct netdev_nested_priv *priv), 7243 struct netdev_nested_priv *priv) 7244 { 7245 struct net_device *ldev, *next, *now, *dev_stack[MAX_NEST_DEV + 1]; 7246 struct list_head *niter, *iter, *iter_stack[MAX_NEST_DEV + 1]; 7247 int ret, cur = 0; 7248 7249 now = dev; 7250 iter = &dev->adj_list.lower; 7251 7252 while (1) { 7253 if (now != dev) { 7254 ret = fn(now, priv); 7255 if (ret) 7256 return ret; 7257 } 7258 7259 next = NULL; 7260 while (1) { 7261 ldev = netdev_next_lower_dev(now, &iter); 7262 if (!ldev) 7263 break; 7264 7265 next = ldev; 7266 niter = &ldev->adj_list.lower; 7267 dev_stack[cur] = now; 7268 iter_stack[cur++] = iter; 7269 break; 7270 } 7271 7272 if (!next) { 7273 if (!cur) 7274 return 0; 7275 next = dev_stack[--cur]; 7276 niter = iter_stack[cur]; 7277 } 7278 7279 now = next; 7280 iter = niter; 7281 } 7282 7283 return 0; 7284 } 7285 EXPORT_SYMBOL_GPL(netdev_walk_all_lower_dev); 7286 7287 static int __netdev_walk_all_lower_dev(struct net_device *dev, 7288 int (*fn)(struct net_device *dev, 7289 struct netdev_nested_priv *priv), 7290 struct netdev_nested_priv *priv) 7291 { 7292 struct net_device *ldev, *next, *now, *dev_stack[MAX_NEST_DEV + 1]; 7293 struct list_head *niter, *iter, *iter_stack[MAX_NEST_DEV + 1]; 7294 int ret, cur = 0; 7295 bool ignore; 7296 7297 now = dev; 7298 iter = &dev->adj_list.lower; 7299 7300 while (1) { 7301 if (now != dev) { 7302 ret = fn(now, priv); 7303 if (ret) 7304 return ret; 7305 } 7306 7307 next = NULL; 7308 while (1) { 7309 ldev = __netdev_next_lower_dev(now, &iter, &ignore); 7310 if (!ldev) 7311 break; 7312 if (ignore) 7313 continue; 7314 7315 next = ldev; 7316 niter = &ldev->adj_list.lower; 7317 dev_stack[cur] = now; 7318 iter_stack[cur++] = iter; 7319 break; 7320 } 7321 7322 if (!next) { 7323 if (!cur) 7324 return 0; 7325 next = dev_stack[--cur]; 7326 niter = iter_stack[cur]; 7327 } 7328 7329 now = next; 7330 iter = niter; 7331 } 7332 7333 return 0; 7334 } 7335 7336 struct net_device *netdev_next_lower_dev_rcu(struct net_device *dev, 7337 struct list_head **iter) 7338 { 7339 struct netdev_adjacent *lower; 7340 7341 lower = list_entry_rcu((*iter)->next, struct netdev_adjacent, list); 7342 if (&lower->list == &dev->adj_list.lower) 7343 return NULL; 7344 7345 *iter = &lower->list; 7346 7347 return lower->dev; 7348 } 7349 EXPORT_SYMBOL(netdev_next_lower_dev_rcu); 7350 7351 static u8 __netdev_upper_depth(struct net_device *dev) 7352 { 7353 struct net_device *udev; 7354 struct list_head *iter; 7355 u8 max_depth = 0; 7356 bool ignore; 7357 7358 for (iter = &dev->adj_list.upper, 7359 udev = __netdev_next_upper_dev(dev, &iter, &ignore); 7360 udev; 7361 udev = __netdev_next_upper_dev(dev, &iter, &ignore)) { 7362 if (ignore) 7363 continue; 7364 if (max_depth < udev->upper_level) 7365 max_depth = udev->upper_level; 7366 } 7367 7368 return max_depth; 7369 } 7370 7371 static u8 __netdev_lower_depth(struct net_device *dev) 7372 { 7373 struct net_device *ldev; 7374 struct list_head *iter; 7375 u8 max_depth = 0; 7376 bool ignore; 7377 7378 for (iter = &dev->adj_list.lower, 7379 ldev = __netdev_next_lower_dev(dev, &iter, &ignore); 7380 ldev; 7381 ldev = __netdev_next_lower_dev(dev, &iter, &ignore)) { 7382 if (ignore) 7383 continue; 7384 if (max_depth < ldev->lower_level) 7385 max_depth = ldev->lower_level; 7386 } 7387 7388 return max_depth; 7389 } 7390 7391 static int __netdev_update_upper_level(struct net_device *dev, 7392 struct netdev_nested_priv *__unused) 7393 { 7394 dev->upper_level = __netdev_upper_depth(dev) + 1; 7395 return 0; 7396 } 7397 7398 #ifdef CONFIG_LOCKDEP 7399 static LIST_HEAD(net_unlink_list); 7400 7401 static void net_unlink_todo(struct net_device *dev) 7402 { 7403 if (list_empty(&dev->unlink_list)) 7404 list_add_tail(&dev->unlink_list, &net_unlink_list); 7405 } 7406 #endif 7407 7408 static int __netdev_update_lower_level(struct net_device *dev, 7409 struct netdev_nested_priv *priv) 7410 { 7411 dev->lower_level = __netdev_lower_depth(dev) + 1; 7412 7413 #ifdef CONFIG_LOCKDEP 7414 if (!priv) 7415 return 0; 7416 7417 if (priv->flags & NESTED_SYNC_IMM) 7418 dev->nested_level = dev->lower_level - 1; 7419 if (priv->flags & NESTED_SYNC_TODO) 7420 net_unlink_todo(dev); 7421 #endif 7422 return 0; 7423 } 7424 7425 int netdev_walk_all_lower_dev_rcu(struct net_device *dev, 7426 int (*fn)(struct net_device *dev, 7427 struct netdev_nested_priv *priv), 7428 struct netdev_nested_priv *priv) 7429 { 7430 struct net_device *ldev, *next, *now, *dev_stack[MAX_NEST_DEV + 1]; 7431 struct list_head *niter, *iter, *iter_stack[MAX_NEST_DEV + 1]; 7432 int ret, cur = 0; 7433 7434 now = dev; 7435 iter = &dev->adj_list.lower; 7436 7437 while (1) { 7438 if (now != dev) { 7439 ret = fn(now, priv); 7440 if (ret) 7441 return ret; 7442 } 7443 7444 next = NULL; 7445 while (1) { 7446 ldev = netdev_next_lower_dev_rcu(now, &iter); 7447 if (!ldev) 7448 break; 7449 7450 next = ldev; 7451 niter = &ldev->adj_list.lower; 7452 dev_stack[cur] = now; 7453 iter_stack[cur++] = iter; 7454 break; 7455 } 7456 7457 if (!next) { 7458 if (!cur) 7459 return 0; 7460 next = dev_stack[--cur]; 7461 niter = iter_stack[cur]; 7462 } 7463 7464 now = next; 7465 iter = niter; 7466 } 7467 7468 return 0; 7469 } 7470 EXPORT_SYMBOL_GPL(netdev_walk_all_lower_dev_rcu); 7471 7472 /** 7473 * netdev_lower_get_first_private_rcu - Get the first ->private from the 7474 * lower neighbour list, RCU 7475 * variant 7476 * @dev: device 7477 * 7478 * Gets the first netdev_adjacent->private from the dev's lower neighbour 7479 * list. The caller must hold RCU read lock. 7480 */ 7481 void *netdev_lower_get_first_private_rcu(struct net_device *dev) 7482 { 7483 struct netdev_adjacent *lower; 7484 7485 lower = list_first_or_null_rcu(&dev->adj_list.lower, 7486 struct netdev_adjacent, list); 7487 if (lower) 7488 return lower->private; 7489 return NULL; 7490 } 7491 EXPORT_SYMBOL(netdev_lower_get_first_private_rcu); 7492 7493 /** 7494 * netdev_master_upper_dev_get_rcu - Get master upper device 7495 * @dev: device 7496 * 7497 * Find a master upper device and return pointer to it or NULL in case 7498 * it's not there. The caller must hold the RCU read lock. 7499 */ 7500 struct net_device *netdev_master_upper_dev_get_rcu(struct net_device *dev) 7501 { 7502 struct netdev_adjacent *upper; 7503 7504 upper = list_first_or_null_rcu(&dev->adj_list.upper, 7505 struct netdev_adjacent, list); 7506 if (upper && likely(upper->master)) 7507 return upper->dev; 7508 return NULL; 7509 } 7510 EXPORT_SYMBOL(netdev_master_upper_dev_get_rcu); 7511 7512 static int netdev_adjacent_sysfs_add(struct net_device *dev, 7513 struct net_device *adj_dev, 7514 struct list_head *dev_list) 7515 { 7516 char linkname[IFNAMSIZ+7]; 7517 7518 sprintf(linkname, dev_list == &dev->adj_list.upper ? 7519 "upper_%s" : "lower_%s", adj_dev->name); 7520 return sysfs_create_link(&(dev->dev.kobj), &(adj_dev->dev.kobj), 7521 linkname); 7522 } 7523 static void netdev_adjacent_sysfs_del(struct net_device *dev, 7524 char *name, 7525 struct list_head *dev_list) 7526 { 7527 char linkname[IFNAMSIZ+7]; 7528 7529 sprintf(linkname, dev_list == &dev->adj_list.upper ? 7530 "upper_%s" : "lower_%s", name); 7531 sysfs_remove_link(&(dev->dev.kobj), linkname); 7532 } 7533 7534 static inline bool netdev_adjacent_is_neigh_list(struct net_device *dev, 7535 struct net_device *adj_dev, 7536 struct list_head *dev_list) 7537 { 7538 return (dev_list == &dev->adj_list.upper || 7539 dev_list == &dev->adj_list.lower) && 7540 net_eq(dev_net(dev), dev_net(adj_dev)); 7541 } 7542 7543 static int __netdev_adjacent_dev_insert(struct net_device *dev, 7544 struct net_device *adj_dev, 7545 struct list_head *dev_list, 7546 void *private, bool master) 7547 { 7548 struct netdev_adjacent *adj; 7549 int ret; 7550 7551 adj = __netdev_find_adj(adj_dev, dev_list); 7552 7553 if (adj) { 7554 adj->ref_nr += 1; 7555 pr_debug("Insert adjacency: dev %s adj_dev %s adj->ref_nr %d\n", 7556 dev->name, adj_dev->name, adj->ref_nr); 7557 7558 return 0; 7559 } 7560 7561 adj = kmalloc(sizeof(*adj), GFP_KERNEL); 7562 if (!adj) 7563 return -ENOMEM; 7564 7565 adj->dev = adj_dev; 7566 adj->master = master; 7567 adj->ref_nr = 1; 7568 adj->private = private; 7569 adj->ignore = false; 7570 netdev_hold(adj_dev, &adj->dev_tracker, GFP_KERNEL); 7571 7572 pr_debug("Insert adjacency: dev %s adj_dev %s adj->ref_nr %d; dev_hold on %s\n", 7573 dev->name, adj_dev->name, adj->ref_nr, adj_dev->name); 7574 7575 if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list)) { 7576 ret = netdev_adjacent_sysfs_add(dev, adj_dev, dev_list); 7577 if (ret) 7578 goto free_adj; 7579 } 7580 7581 /* Ensure that master link is always the first item in list. */ 7582 if (master) { 7583 ret = sysfs_create_link(&(dev->dev.kobj), 7584 &(adj_dev->dev.kobj), "master"); 7585 if (ret) 7586 goto remove_symlinks; 7587 7588 list_add_rcu(&adj->list, dev_list); 7589 } else { 7590 list_add_tail_rcu(&adj->list, dev_list); 7591 } 7592 7593 return 0; 7594 7595 remove_symlinks: 7596 if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list)) 7597 netdev_adjacent_sysfs_del(dev, adj_dev->name, dev_list); 7598 free_adj: 7599 netdev_put(adj_dev, &adj->dev_tracker); 7600 kfree(adj); 7601 7602 return ret; 7603 } 7604 7605 static void __netdev_adjacent_dev_remove(struct net_device *dev, 7606 struct net_device *adj_dev, 7607 u16 ref_nr, 7608 struct list_head *dev_list) 7609 { 7610 struct netdev_adjacent *adj; 7611 7612 pr_debug("Remove adjacency: dev %s adj_dev %s ref_nr %d\n", 7613 dev->name, adj_dev->name, ref_nr); 7614 7615 adj = __netdev_find_adj(adj_dev, dev_list); 7616 7617 if (!adj) { 7618 pr_err("Adjacency does not exist for device %s from %s\n", 7619 dev->name, adj_dev->name); 7620 WARN_ON(1); 7621 return; 7622 } 7623 7624 if (adj->ref_nr > ref_nr) { 7625 pr_debug("adjacency: %s to %s ref_nr - %d = %d\n", 7626 dev->name, adj_dev->name, ref_nr, 7627 adj->ref_nr - ref_nr); 7628 adj->ref_nr -= ref_nr; 7629 return; 7630 } 7631 7632 if (adj->master) 7633 sysfs_remove_link(&(dev->dev.kobj), "master"); 7634 7635 if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list)) 7636 netdev_adjacent_sysfs_del(dev, adj_dev->name, dev_list); 7637 7638 list_del_rcu(&adj->list); 7639 pr_debug("adjacency: dev_put for %s, because link removed from %s to %s\n", 7640 adj_dev->name, dev->name, adj_dev->name); 7641 netdev_put(adj_dev, &adj->dev_tracker); 7642 kfree_rcu(adj, rcu); 7643 } 7644 7645 static int __netdev_adjacent_dev_link_lists(struct net_device *dev, 7646 struct net_device *upper_dev, 7647 struct list_head *up_list, 7648 struct list_head *down_list, 7649 void *private, bool master) 7650 { 7651 int ret; 7652 7653 ret = __netdev_adjacent_dev_insert(dev, upper_dev, up_list, 7654 private, master); 7655 if (ret) 7656 return ret; 7657 7658 ret = __netdev_adjacent_dev_insert(upper_dev, dev, down_list, 7659 private, false); 7660 if (ret) { 7661 __netdev_adjacent_dev_remove(dev, upper_dev, 1, up_list); 7662 return ret; 7663 } 7664 7665 return 0; 7666 } 7667 7668 static void __netdev_adjacent_dev_unlink_lists(struct net_device *dev, 7669 struct net_device *upper_dev, 7670 u16 ref_nr, 7671 struct list_head *up_list, 7672 struct list_head *down_list) 7673 { 7674 __netdev_adjacent_dev_remove(dev, upper_dev, ref_nr, up_list); 7675 __netdev_adjacent_dev_remove(upper_dev, dev, ref_nr, down_list); 7676 } 7677 7678 static int __netdev_adjacent_dev_link_neighbour(struct net_device *dev, 7679 struct net_device *upper_dev, 7680 void *private, bool master) 7681 { 7682 return __netdev_adjacent_dev_link_lists(dev, upper_dev, 7683 &dev->adj_list.upper, 7684 &upper_dev->adj_list.lower, 7685 private, master); 7686 } 7687 7688 static void __netdev_adjacent_dev_unlink_neighbour(struct net_device *dev, 7689 struct net_device *upper_dev) 7690 { 7691 __netdev_adjacent_dev_unlink_lists(dev, upper_dev, 1, 7692 &dev->adj_list.upper, 7693 &upper_dev->adj_list.lower); 7694 } 7695 7696 static int __netdev_upper_dev_link(struct net_device *dev, 7697 struct net_device *upper_dev, bool master, 7698 void *upper_priv, void *upper_info, 7699 struct netdev_nested_priv *priv, 7700 struct netlink_ext_ack *extack) 7701 { 7702 struct netdev_notifier_changeupper_info changeupper_info = { 7703 .info = { 7704 .dev = dev, 7705 .extack = extack, 7706 }, 7707 .upper_dev = upper_dev, 7708 .master = master, 7709 .linking = true, 7710 .upper_info = upper_info, 7711 }; 7712 struct net_device *master_dev; 7713 int ret = 0; 7714 7715 ASSERT_RTNL(); 7716 7717 if (dev == upper_dev) 7718 return -EBUSY; 7719 7720 /* To prevent loops, check if dev is not upper device to upper_dev. */ 7721 if (__netdev_has_upper_dev(upper_dev, dev)) 7722 return -EBUSY; 7723 7724 if ((dev->lower_level + upper_dev->upper_level) > MAX_NEST_DEV) 7725 return -EMLINK; 7726 7727 if (!master) { 7728 if (__netdev_has_upper_dev(dev, upper_dev)) 7729 return -EEXIST; 7730 } else { 7731 master_dev = __netdev_master_upper_dev_get(dev); 7732 if (master_dev) 7733 return master_dev == upper_dev ? -EEXIST : -EBUSY; 7734 } 7735 7736 ret = call_netdevice_notifiers_info(NETDEV_PRECHANGEUPPER, 7737 &changeupper_info.info); 7738 ret = notifier_to_errno(ret); 7739 if (ret) 7740 return ret; 7741 7742 ret = __netdev_adjacent_dev_link_neighbour(dev, upper_dev, upper_priv, 7743 master); 7744 if (ret) 7745 return ret; 7746 7747 ret = call_netdevice_notifiers_info(NETDEV_CHANGEUPPER, 7748 &changeupper_info.info); 7749 ret = notifier_to_errno(ret); 7750 if (ret) 7751 goto rollback; 7752 7753 __netdev_update_upper_level(dev, NULL); 7754 __netdev_walk_all_lower_dev(dev, __netdev_update_upper_level, NULL); 7755 7756 __netdev_update_lower_level(upper_dev, priv); 7757 __netdev_walk_all_upper_dev(upper_dev, __netdev_update_lower_level, 7758 priv); 7759 7760 return 0; 7761 7762 rollback: 7763 __netdev_adjacent_dev_unlink_neighbour(dev, upper_dev); 7764 7765 return ret; 7766 } 7767 7768 /** 7769 * netdev_upper_dev_link - Add a link to the upper device 7770 * @dev: device 7771 * @upper_dev: new upper device 7772 * @extack: netlink extended ack 7773 * 7774 * Adds a link to device which is upper to this one. The caller must hold 7775 * the RTNL lock. On a failure a negative errno code is returned. 7776 * On success the reference counts are adjusted and the function 7777 * returns zero. 7778 */ 7779 int netdev_upper_dev_link(struct net_device *dev, 7780 struct net_device *upper_dev, 7781 struct netlink_ext_ack *extack) 7782 { 7783 struct netdev_nested_priv priv = { 7784 .flags = NESTED_SYNC_IMM | NESTED_SYNC_TODO, 7785 .data = NULL, 7786 }; 7787 7788 return __netdev_upper_dev_link(dev, upper_dev, false, 7789 NULL, NULL, &priv, extack); 7790 } 7791 EXPORT_SYMBOL(netdev_upper_dev_link); 7792 7793 /** 7794 * netdev_master_upper_dev_link - Add a master link to the upper device 7795 * @dev: device 7796 * @upper_dev: new upper device 7797 * @upper_priv: upper device private 7798 * @upper_info: upper info to be passed down via notifier 7799 * @extack: netlink extended ack 7800 * 7801 * Adds a link to device which is upper to this one. In this case, only 7802 * one master upper device can be linked, although other non-master devices 7803 * might be linked as well. The caller must hold the RTNL lock. 7804 * On a failure a negative errno code is returned. On success the reference 7805 * counts are adjusted and the function returns zero. 7806 */ 7807 int netdev_master_upper_dev_link(struct net_device *dev, 7808 struct net_device *upper_dev, 7809 void *upper_priv, void *upper_info, 7810 struct netlink_ext_ack *extack) 7811 { 7812 struct netdev_nested_priv priv = { 7813 .flags = NESTED_SYNC_IMM | NESTED_SYNC_TODO, 7814 .data = NULL, 7815 }; 7816 7817 return __netdev_upper_dev_link(dev, upper_dev, true, 7818 upper_priv, upper_info, &priv, extack); 7819 } 7820 EXPORT_SYMBOL(netdev_master_upper_dev_link); 7821 7822 static void __netdev_upper_dev_unlink(struct net_device *dev, 7823 struct net_device *upper_dev, 7824 struct netdev_nested_priv *priv) 7825 { 7826 struct netdev_notifier_changeupper_info changeupper_info = { 7827 .info = { 7828 .dev = dev, 7829 }, 7830 .upper_dev = upper_dev, 7831 .linking = false, 7832 }; 7833 7834 ASSERT_RTNL(); 7835 7836 changeupper_info.master = netdev_master_upper_dev_get(dev) == upper_dev; 7837 7838 call_netdevice_notifiers_info(NETDEV_PRECHANGEUPPER, 7839 &changeupper_info.info); 7840 7841 __netdev_adjacent_dev_unlink_neighbour(dev, upper_dev); 7842 7843 call_netdevice_notifiers_info(NETDEV_CHANGEUPPER, 7844 &changeupper_info.info); 7845 7846 __netdev_update_upper_level(dev, NULL); 7847 __netdev_walk_all_lower_dev(dev, __netdev_update_upper_level, NULL); 7848 7849 __netdev_update_lower_level(upper_dev, priv); 7850 __netdev_walk_all_upper_dev(upper_dev, __netdev_update_lower_level, 7851 priv); 7852 } 7853 7854 /** 7855 * netdev_upper_dev_unlink - Removes a link to upper device 7856 * @dev: device 7857 * @upper_dev: new upper device 7858 * 7859 * Removes a link to device which is upper to this one. The caller must hold 7860 * the RTNL lock. 7861 */ 7862 void netdev_upper_dev_unlink(struct net_device *dev, 7863 struct net_device *upper_dev) 7864 { 7865 struct netdev_nested_priv priv = { 7866 .flags = NESTED_SYNC_TODO, 7867 .data = NULL, 7868 }; 7869 7870 __netdev_upper_dev_unlink(dev, upper_dev, &priv); 7871 } 7872 EXPORT_SYMBOL(netdev_upper_dev_unlink); 7873 7874 static void __netdev_adjacent_dev_set(struct net_device *upper_dev, 7875 struct net_device *lower_dev, 7876 bool val) 7877 { 7878 struct netdev_adjacent *adj; 7879 7880 adj = __netdev_find_adj(lower_dev, &upper_dev->adj_list.lower); 7881 if (adj) 7882 adj->ignore = val; 7883 7884 adj = __netdev_find_adj(upper_dev, &lower_dev->adj_list.upper); 7885 if (adj) 7886 adj->ignore = val; 7887 } 7888 7889 static void netdev_adjacent_dev_disable(struct net_device *upper_dev, 7890 struct net_device *lower_dev) 7891 { 7892 __netdev_adjacent_dev_set(upper_dev, lower_dev, true); 7893 } 7894 7895 static void netdev_adjacent_dev_enable(struct net_device *upper_dev, 7896 struct net_device *lower_dev) 7897 { 7898 __netdev_adjacent_dev_set(upper_dev, lower_dev, false); 7899 } 7900 7901 int netdev_adjacent_change_prepare(struct net_device *old_dev, 7902 struct net_device *new_dev, 7903 struct net_device *dev, 7904 struct netlink_ext_ack *extack) 7905 { 7906 struct netdev_nested_priv priv = { 7907 .flags = 0, 7908 .data = NULL, 7909 }; 7910 int err; 7911 7912 if (!new_dev) 7913 return 0; 7914 7915 if (old_dev && new_dev != old_dev) 7916 netdev_adjacent_dev_disable(dev, old_dev); 7917 err = __netdev_upper_dev_link(new_dev, dev, false, NULL, NULL, &priv, 7918 extack); 7919 if (err) { 7920 if (old_dev && new_dev != old_dev) 7921 netdev_adjacent_dev_enable(dev, old_dev); 7922 return err; 7923 } 7924 7925 return 0; 7926 } 7927 EXPORT_SYMBOL(netdev_adjacent_change_prepare); 7928 7929 void netdev_adjacent_change_commit(struct net_device *old_dev, 7930 struct net_device *new_dev, 7931 struct net_device *dev) 7932 { 7933 struct netdev_nested_priv priv = { 7934 .flags = NESTED_SYNC_IMM | NESTED_SYNC_TODO, 7935 .data = NULL, 7936 }; 7937 7938 if (!new_dev || !old_dev) 7939 return; 7940 7941 if (new_dev == old_dev) 7942 return; 7943 7944 netdev_adjacent_dev_enable(dev, old_dev); 7945 __netdev_upper_dev_unlink(old_dev, dev, &priv); 7946 } 7947 EXPORT_SYMBOL(netdev_adjacent_change_commit); 7948 7949 void netdev_adjacent_change_abort(struct net_device *old_dev, 7950 struct net_device *new_dev, 7951 struct net_device *dev) 7952 { 7953 struct netdev_nested_priv priv = { 7954 .flags = 0, 7955 .data = NULL, 7956 }; 7957 7958 if (!new_dev) 7959 return; 7960 7961 if (old_dev && new_dev != old_dev) 7962 netdev_adjacent_dev_enable(dev, old_dev); 7963 7964 __netdev_upper_dev_unlink(new_dev, dev, &priv); 7965 } 7966 EXPORT_SYMBOL(netdev_adjacent_change_abort); 7967 7968 /** 7969 * netdev_bonding_info_change - Dispatch event about slave change 7970 * @dev: device 7971 * @bonding_info: info to dispatch 7972 * 7973 * Send NETDEV_BONDING_INFO to netdev notifiers with info. 7974 * The caller must hold the RTNL lock. 7975 */ 7976 void netdev_bonding_info_change(struct net_device *dev, 7977 struct netdev_bonding_info *bonding_info) 7978 { 7979 struct netdev_notifier_bonding_info info = { 7980 .info.dev = dev, 7981 }; 7982 7983 memcpy(&info.bonding_info, bonding_info, 7984 sizeof(struct netdev_bonding_info)); 7985 call_netdevice_notifiers_info(NETDEV_BONDING_INFO, 7986 &info.info); 7987 } 7988 EXPORT_SYMBOL(netdev_bonding_info_change); 7989 7990 static int netdev_offload_xstats_enable_l3(struct net_device *dev, 7991 struct netlink_ext_ack *extack) 7992 { 7993 struct netdev_notifier_offload_xstats_info info = { 7994 .info.dev = dev, 7995 .info.extack = extack, 7996 .type = NETDEV_OFFLOAD_XSTATS_TYPE_L3, 7997 }; 7998 int err; 7999 int rc; 8000 8001 dev->offload_xstats_l3 = kzalloc(sizeof(*dev->offload_xstats_l3), 8002 GFP_KERNEL); 8003 if (!dev->offload_xstats_l3) 8004 return -ENOMEM; 8005 8006 rc = call_netdevice_notifiers_info_robust(NETDEV_OFFLOAD_XSTATS_ENABLE, 8007 NETDEV_OFFLOAD_XSTATS_DISABLE, 8008 &info.info); 8009 err = notifier_to_errno(rc); 8010 if (err) 8011 goto free_stats; 8012 8013 return 0; 8014 8015 free_stats: 8016 kfree(dev->offload_xstats_l3); 8017 dev->offload_xstats_l3 = NULL; 8018 return err; 8019 } 8020 8021 int netdev_offload_xstats_enable(struct net_device *dev, 8022 enum netdev_offload_xstats_type type, 8023 struct netlink_ext_ack *extack) 8024 { 8025 ASSERT_RTNL(); 8026 8027 if (netdev_offload_xstats_enabled(dev, type)) 8028 return -EALREADY; 8029 8030 switch (type) { 8031 case NETDEV_OFFLOAD_XSTATS_TYPE_L3: 8032 return netdev_offload_xstats_enable_l3(dev, extack); 8033 } 8034 8035 WARN_ON(1); 8036 return -EINVAL; 8037 } 8038 EXPORT_SYMBOL(netdev_offload_xstats_enable); 8039 8040 static void netdev_offload_xstats_disable_l3(struct net_device *dev) 8041 { 8042 struct netdev_notifier_offload_xstats_info info = { 8043 .info.dev = dev, 8044 .type = NETDEV_OFFLOAD_XSTATS_TYPE_L3, 8045 }; 8046 8047 call_netdevice_notifiers_info(NETDEV_OFFLOAD_XSTATS_DISABLE, 8048 &info.info); 8049 kfree(dev->offload_xstats_l3); 8050 dev->offload_xstats_l3 = NULL; 8051 } 8052 8053 int netdev_offload_xstats_disable(struct net_device *dev, 8054 enum netdev_offload_xstats_type type) 8055 { 8056 ASSERT_RTNL(); 8057 8058 if (!netdev_offload_xstats_enabled(dev, type)) 8059 return -EALREADY; 8060 8061 switch (type) { 8062 case NETDEV_OFFLOAD_XSTATS_TYPE_L3: 8063 netdev_offload_xstats_disable_l3(dev); 8064 return 0; 8065 } 8066 8067 WARN_ON(1); 8068 return -EINVAL; 8069 } 8070 EXPORT_SYMBOL(netdev_offload_xstats_disable); 8071 8072 static void netdev_offload_xstats_disable_all(struct net_device *dev) 8073 { 8074 netdev_offload_xstats_disable(dev, NETDEV_OFFLOAD_XSTATS_TYPE_L3); 8075 } 8076 8077 static struct rtnl_hw_stats64 * 8078 netdev_offload_xstats_get_ptr(const struct net_device *dev, 8079 enum netdev_offload_xstats_type type) 8080 { 8081 switch (type) { 8082 case NETDEV_OFFLOAD_XSTATS_TYPE_L3: 8083 return dev->offload_xstats_l3; 8084 } 8085 8086 WARN_ON(1); 8087 return NULL; 8088 } 8089 8090 bool netdev_offload_xstats_enabled(const struct net_device *dev, 8091 enum netdev_offload_xstats_type type) 8092 { 8093 ASSERT_RTNL(); 8094 8095 return netdev_offload_xstats_get_ptr(dev, type); 8096 } 8097 EXPORT_SYMBOL(netdev_offload_xstats_enabled); 8098 8099 struct netdev_notifier_offload_xstats_ru { 8100 bool used; 8101 }; 8102 8103 struct netdev_notifier_offload_xstats_rd { 8104 struct rtnl_hw_stats64 stats; 8105 bool used; 8106 }; 8107 8108 static void netdev_hw_stats64_add(struct rtnl_hw_stats64 *dest, 8109 const struct rtnl_hw_stats64 *src) 8110 { 8111 dest->rx_packets += src->rx_packets; 8112 dest->tx_packets += src->tx_packets; 8113 dest->rx_bytes += src->rx_bytes; 8114 dest->tx_bytes += src->tx_bytes; 8115 dest->rx_errors += src->rx_errors; 8116 dest->tx_errors += src->tx_errors; 8117 dest->rx_dropped += src->rx_dropped; 8118 dest->tx_dropped += src->tx_dropped; 8119 dest->multicast += src->multicast; 8120 } 8121 8122 static int netdev_offload_xstats_get_used(struct net_device *dev, 8123 enum netdev_offload_xstats_type type, 8124 bool *p_used, 8125 struct netlink_ext_ack *extack) 8126 { 8127 struct netdev_notifier_offload_xstats_ru report_used = {}; 8128 struct netdev_notifier_offload_xstats_info info = { 8129 .info.dev = dev, 8130 .info.extack = extack, 8131 .type = type, 8132 .report_used = &report_used, 8133 }; 8134 int rc; 8135 8136 WARN_ON(!netdev_offload_xstats_enabled(dev, type)); 8137 rc = call_netdevice_notifiers_info(NETDEV_OFFLOAD_XSTATS_REPORT_USED, 8138 &info.info); 8139 *p_used = report_used.used; 8140 return notifier_to_errno(rc); 8141 } 8142 8143 static int netdev_offload_xstats_get_stats(struct net_device *dev, 8144 enum netdev_offload_xstats_type type, 8145 struct rtnl_hw_stats64 *p_stats, 8146 bool *p_used, 8147 struct netlink_ext_ack *extack) 8148 { 8149 struct netdev_notifier_offload_xstats_rd report_delta = {}; 8150 struct netdev_notifier_offload_xstats_info info = { 8151 .info.dev = dev, 8152 .info.extack = extack, 8153 .type = type, 8154 .report_delta = &report_delta, 8155 }; 8156 struct rtnl_hw_stats64 *stats; 8157 int rc; 8158 8159 stats = netdev_offload_xstats_get_ptr(dev, type); 8160 if (WARN_ON(!stats)) 8161 return -EINVAL; 8162 8163 rc = call_netdevice_notifiers_info(NETDEV_OFFLOAD_XSTATS_REPORT_DELTA, 8164 &info.info); 8165 8166 /* Cache whatever we got, even if there was an error, otherwise the 8167 * successful stats retrievals would get lost. 8168 */ 8169 netdev_hw_stats64_add(stats, &report_delta.stats); 8170 8171 if (p_stats) 8172 *p_stats = *stats; 8173 *p_used = report_delta.used; 8174 8175 return notifier_to_errno(rc); 8176 } 8177 8178 int netdev_offload_xstats_get(struct net_device *dev, 8179 enum netdev_offload_xstats_type type, 8180 struct rtnl_hw_stats64 *p_stats, bool *p_used, 8181 struct netlink_ext_ack *extack) 8182 { 8183 ASSERT_RTNL(); 8184 8185 if (p_stats) 8186 return netdev_offload_xstats_get_stats(dev, type, p_stats, 8187 p_used, extack); 8188 else 8189 return netdev_offload_xstats_get_used(dev, type, p_used, 8190 extack); 8191 } 8192 EXPORT_SYMBOL(netdev_offload_xstats_get); 8193 8194 void 8195 netdev_offload_xstats_report_delta(struct netdev_notifier_offload_xstats_rd *report_delta, 8196 const struct rtnl_hw_stats64 *stats) 8197 { 8198 report_delta->used = true; 8199 netdev_hw_stats64_add(&report_delta->stats, stats); 8200 } 8201 EXPORT_SYMBOL(netdev_offload_xstats_report_delta); 8202 8203 void 8204 netdev_offload_xstats_report_used(struct netdev_notifier_offload_xstats_ru *report_used) 8205 { 8206 report_used->used = true; 8207 } 8208 EXPORT_SYMBOL(netdev_offload_xstats_report_used); 8209 8210 void netdev_offload_xstats_push_delta(struct net_device *dev, 8211 enum netdev_offload_xstats_type type, 8212 const struct rtnl_hw_stats64 *p_stats) 8213 { 8214 struct rtnl_hw_stats64 *stats; 8215 8216 ASSERT_RTNL(); 8217 8218 stats = netdev_offload_xstats_get_ptr(dev, type); 8219 if (WARN_ON(!stats)) 8220 return; 8221 8222 netdev_hw_stats64_add(stats, p_stats); 8223 } 8224 EXPORT_SYMBOL(netdev_offload_xstats_push_delta); 8225 8226 /** 8227 * netdev_get_xmit_slave - Get the xmit slave of master device 8228 * @dev: device 8229 * @skb: The packet 8230 * @all_slaves: assume all the slaves are active 8231 * 8232 * The reference counters are not incremented so the caller must be 8233 * careful with locks. The caller must hold RCU lock. 8234 * %NULL is returned if no slave is found. 8235 */ 8236 8237 struct net_device *netdev_get_xmit_slave(struct net_device *dev, 8238 struct sk_buff *skb, 8239 bool all_slaves) 8240 { 8241 const struct net_device_ops *ops = dev->netdev_ops; 8242 8243 if (!ops->ndo_get_xmit_slave) 8244 return NULL; 8245 return ops->ndo_get_xmit_slave(dev, skb, all_slaves); 8246 } 8247 EXPORT_SYMBOL(netdev_get_xmit_slave); 8248 8249 static struct net_device *netdev_sk_get_lower_dev(struct net_device *dev, 8250 struct sock *sk) 8251 { 8252 const struct net_device_ops *ops = dev->netdev_ops; 8253 8254 if (!ops->ndo_sk_get_lower_dev) 8255 return NULL; 8256 return ops->ndo_sk_get_lower_dev(dev, sk); 8257 } 8258 8259 /** 8260 * netdev_sk_get_lowest_dev - Get the lowest device in chain given device and socket 8261 * @dev: device 8262 * @sk: the socket 8263 * 8264 * %NULL is returned if no lower device is found. 8265 */ 8266 8267 struct net_device *netdev_sk_get_lowest_dev(struct net_device *dev, 8268 struct sock *sk) 8269 { 8270 struct net_device *lower; 8271 8272 lower = netdev_sk_get_lower_dev(dev, sk); 8273 while (lower) { 8274 dev = lower; 8275 lower = netdev_sk_get_lower_dev(dev, sk); 8276 } 8277 8278 return dev; 8279 } 8280 EXPORT_SYMBOL(netdev_sk_get_lowest_dev); 8281 8282 static void netdev_adjacent_add_links(struct net_device *dev) 8283 { 8284 struct netdev_adjacent *iter; 8285 8286 struct net *net = dev_net(dev); 8287 8288 list_for_each_entry(iter, &dev->adj_list.upper, list) { 8289 if (!net_eq(net, dev_net(iter->dev))) 8290 continue; 8291 netdev_adjacent_sysfs_add(iter->dev, dev, 8292 &iter->dev->adj_list.lower); 8293 netdev_adjacent_sysfs_add(dev, iter->dev, 8294 &dev->adj_list.upper); 8295 } 8296 8297 list_for_each_entry(iter, &dev->adj_list.lower, list) { 8298 if (!net_eq(net, dev_net(iter->dev))) 8299 continue; 8300 netdev_adjacent_sysfs_add(iter->dev, dev, 8301 &iter->dev->adj_list.upper); 8302 netdev_adjacent_sysfs_add(dev, iter->dev, 8303 &dev->adj_list.lower); 8304 } 8305 } 8306 8307 static void netdev_adjacent_del_links(struct net_device *dev) 8308 { 8309 struct netdev_adjacent *iter; 8310 8311 struct net *net = dev_net(dev); 8312 8313 list_for_each_entry(iter, &dev->adj_list.upper, list) { 8314 if (!net_eq(net, dev_net(iter->dev))) 8315 continue; 8316 netdev_adjacent_sysfs_del(iter->dev, dev->name, 8317 &iter->dev->adj_list.lower); 8318 netdev_adjacent_sysfs_del(dev, iter->dev->name, 8319 &dev->adj_list.upper); 8320 } 8321 8322 list_for_each_entry(iter, &dev->adj_list.lower, list) { 8323 if (!net_eq(net, dev_net(iter->dev))) 8324 continue; 8325 netdev_adjacent_sysfs_del(iter->dev, dev->name, 8326 &iter->dev->adj_list.upper); 8327 netdev_adjacent_sysfs_del(dev, iter->dev->name, 8328 &dev->adj_list.lower); 8329 } 8330 } 8331 8332 void netdev_adjacent_rename_links(struct net_device *dev, char *oldname) 8333 { 8334 struct netdev_adjacent *iter; 8335 8336 struct net *net = dev_net(dev); 8337 8338 list_for_each_entry(iter, &dev->adj_list.upper, list) { 8339 if (!net_eq(net, dev_net(iter->dev))) 8340 continue; 8341 netdev_adjacent_sysfs_del(iter->dev, oldname, 8342 &iter->dev->adj_list.lower); 8343 netdev_adjacent_sysfs_add(iter->dev, dev, 8344 &iter->dev->adj_list.lower); 8345 } 8346 8347 list_for_each_entry(iter, &dev->adj_list.lower, list) { 8348 if (!net_eq(net, dev_net(iter->dev))) 8349 continue; 8350 netdev_adjacent_sysfs_del(iter->dev, oldname, 8351 &iter->dev->adj_list.upper); 8352 netdev_adjacent_sysfs_add(iter->dev, dev, 8353 &iter->dev->adj_list.upper); 8354 } 8355 } 8356 8357 void *netdev_lower_dev_get_private(struct net_device *dev, 8358 struct net_device *lower_dev) 8359 { 8360 struct netdev_adjacent *lower; 8361 8362 if (!lower_dev) 8363 return NULL; 8364 lower = __netdev_find_adj(lower_dev, &dev->adj_list.lower); 8365 if (!lower) 8366 return NULL; 8367 8368 return lower->private; 8369 } 8370 EXPORT_SYMBOL(netdev_lower_dev_get_private); 8371 8372 8373 /** 8374 * netdev_lower_state_changed - Dispatch event about lower device state change 8375 * @lower_dev: device 8376 * @lower_state_info: state to dispatch 8377 * 8378 * Send NETDEV_CHANGELOWERSTATE to netdev notifiers with info. 8379 * The caller must hold the RTNL lock. 8380 */ 8381 void netdev_lower_state_changed(struct net_device *lower_dev, 8382 void *lower_state_info) 8383 { 8384 struct netdev_notifier_changelowerstate_info changelowerstate_info = { 8385 .info.dev = lower_dev, 8386 }; 8387 8388 ASSERT_RTNL(); 8389 changelowerstate_info.lower_state_info = lower_state_info; 8390 call_netdevice_notifiers_info(NETDEV_CHANGELOWERSTATE, 8391 &changelowerstate_info.info); 8392 } 8393 EXPORT_SYMBOL(netdev_lower_state_changed); 8394 8395 static void dev_change_rx_flags(struct net_device *dev, int flags) 8396 { 8397 const struct net_device_ops *ops = dev->netdev_ops; 8398 8399 if (ops->ndo_change_rx_flags) 8400 ops->ndo_change_rx_flags(dev, flags); 8401 } 8402 8403 static int __dev_set_promiscuity(struct net_device *dev, int inc, bool notify) 8404 { 8405 unsigned int old_flags = dev->flags; 8406 kuid_t uid; 8407 kgid_t gid; 8408 8409 ASSERT_RTNL(); 8410 8411 dev->flags |= IFF_PROMISC; 8412 dev->promiscuity += inc; 8413 if (dev->promiscuity == 0) { 8414 /* 8415 * Avoid overflow. 8416 * If inc causes overflow, untouch promisc and return error. 8417 */ 8418 if (inc < 0) 8419 dev->flags &= ~IFF_PROMISC; 8420 else { 8421 dev->promiscuity -= inc; 8422 netdev_warn(dev, "promiscuity touches roof, set promiscuity failed. promiscuity feature of device might be broken.\n"); 8423 return -EOVERFLOW; 8424 } 8425 } 8426 if (dev->flags != old_flags) { 8427 netdev_info(dev, "%s promiscuous mode\n", 8428 dev->flags & IFF_PROMISC ? "entered" : "left"); 8429 if (audit_enabled) { 8430 current_uid_gid(&uid, &gid); 8431 audit_log(audit_context(), GFP_ATOMIC, 8432 AUDIT_ANOM_PROMISCUOUS, 8433 "dev=%s prom=%d old_prom=%d auid=%u uid=%u gid=%u ses=%u", 8434 dev->name, (dev->flags & IFF_PROMISC), 8435 (old_flags & IFF_PROMISC), 8436 from_kuid(&init_user_ns, audit_get_loginuid(current)), 8437 from_kuid(&init_user_ns, uid), 8438 from_kgid(&init_user_ns, gid), 8439 audit_get_sessionid(current)); 8440 } 8441 8442 dev_change_rx_flags(dev, IFF_PROMISC); 8443 } 8444 if (notify) 8445 __dev_notify_flags(dev, old_flags, IFF_PROMISC, 0, NULL); 8446 return 0; 8447 } 8448 8449 /** 8450 * dev_set_promiscuity - update promiscuity count on a device 8451 * @dev: device 8452 * @inc: modifier 8453 * 8454 * Add or remove promiscuity from a device. While the count in the device 8455 * remains above zero the interface remains promiscuous. Once it hits zero 8456 * the device reverts back to normal filtering operation. A negative inc 8457 * value is used to drop promiscuity on the device. 8458 * Return 0 if successful or a negative errno code on error. 8459 */ 8460 int dev_set_promiscuity(struct net_device *dev, int inc) 8461 { 8462 unsigned int old_flags = dev->flags; 8463 int err; 8464 8465 err = __dev_set_promiscuity(dev, inc, true); 8466 if (err < 0) 8467 return err; 8468 if (dev->flags != old_flags) 8469 dev_set_rx_mode(dev); 8470 return err; 8471 } 8472 EXPORT_SYMBOL(dev_set_promiscuity); 8473 8474 static int __dev_set_allmulti(struct net_device *dev, int inc, bool notify) 8475 { 8476 unsigned int old_flags = dev->flags, old_gflags = dev->gflags; 8477 8478 ASSERT_RTNL(); 8479 8480 dev->flags |= IFF_ALLMULTI; 8481 dev->allmulti += inc; 8482 if (dev->allmulti == 0) { 8483 /* 8484 * Avoid overflow. 8485 * If inc causes overflow, untouch allmulti and return error. 8486 */ 8487 if (inc < 0) 8488 dev->flags &= ~IFF_ALLMULTI; 8489 else { 8490 dev->allmulti -= inc; 8491 netdev_warn(dev, "allmulti touches roof, set allmulti failed. allmulti feature of device might be broken.\n"); 8492 return -EOVERFLOW; 8493 } 8494 } 8495 if (dev->flags ^ old_flags) { 8496 netdev_info(dev, "%s allmulticast mode\n", 8497 dev->flags & IFF_ALLMULTI ? "entered" : "left"); 8498 dev_change_rx_flags(dev, IFF_ALLMULTI); 8499 dev_set_rx_mode(dev); 8500 if (notify) 8501 __dev_notify_flags(dev, old_flags, 8502 dev->gflags ^ old_gflags, 0, NULL); 8503 } 8504 return 0; 8505 } 8506 8507 /** 8508 * dev_set_allmulti - update allmulti count on a device 8509 * @dev: device 8510 * @inc: modifier 8511 * 8512 * Add or remove reception of all multicast frames to a device. While the 8513 * count in the device remains above zero the interface remains listening 8514 * to all interfaces. Once it hits zero the device reverts back to normal 8515 * filtering operation. A negative @inc value is used to drop the counter 8516 * when releasing a resource needing all multicasts. 8517 * Return 0 if successful or a negative errno code on error. 8518 */ 8519 8520 int dev_set_allmulti(struct net_device *dev, int inc) 8521 { 8522 return __dev_set_allmulti(dev, inc, true); 8523 } 8524 EXPORT_SYMBOL(dev_set_allmulti); 8525 8526 /* 8527 * Upload unicast and multicast address lists to device and 8528 * configure RX filtering. When the device doesn't support unicast 8529 * filtering it is put in promiscuous mode while unicast addresses 8530 * are present. 8531 */ 8532 void __dev_set_rx_mode(struct net_device *dev) 8533 { 8534 const struct net_device_ops *ops = dev->netdev_ops; 8535 8536 /* dev_open will call this function so the list will stay sane. */ 8537 if (!(dev->flags&IFF_UP)) 8538 return; 8539 8540 if (!netif_device_present(dev)) 8541 return; 8542 8543 if (!(dev->priv_flags & IFF_UNICAST_FLT)) { 8544 /* Unicast addresses changes may only happen under the rtnl, 8545 * therefore calling __dev_set_promiscuity here is safe. 8546 */ 8547 if (!netdev_uc_empty(dev) && !dev->uc_promisc) { 8548 __dev_set_promiscuity(dev, 1, false); 8549 dev->uc_promisc = true; 8550 } else if (netdev_uc_empty(dev) && dev->uc_promisc) { 8551 __dev_set_promiscuity(dev, -1, false); 8552 dev->uc_promisc = false; 8553 } 8554 } 8555 8556 if (ops->ndo_set_rx_mode) 8557 ops->ndo_set_rx_mode(dev); 8558 } 8559 8560 void dev_set_rx_mode(struct net_device *dev) 8561 { 8562 netif_addr_lock_bh(dev); 8563 __dev_set_rx_mode(dev); 8564 netif_addr_unlock_bh(dev); 8565 } 8566 8567 /** 8568 * dev_get_flags - get flags reported to userspace 8569 * @dev: device 8570 * 8571 * Get the combination of flag bits exported through APIs to userspace. 8572 */ 8573 unsigned int dev_get_flags(const struct net_device *dev) 8574 { 8575 unsigned int flags; 8576 8577 flags = (dev->flags & ~(IFF_PROMISC | 8578 IFF_ALLMULTI | 8579 IFF_RUNNING | 8580 IFF_LOWER_UP | 8581 IFF_DORMANT)) | 8582 (dev->gflags & (IFF_PROMISC | 8583 IFF_ALLMULTI)); 8584 8585 if (netif_running(dev)) { 8586 if (netif_oper_up(dev)) 8587 flags |= IFF_RUNNING; 8588 if (netif_carrier_ok(dev)) 8589 flags |= IFF_LOWER_UP; 8590 if (netif_dormant(dev)) 8591 flags |= IFF_DORMANT; 8592 } 8593 8594 return flags; 8595 } 8596 EXPORT_SYMBOL(dev_get_flags); 8597 8598 int __dev_change_flags(struct net_device *dev, unsigned int flags, 8599 struct netlink_ext_ack *extack) 8600 { 8601 unsigned int old_flags = dev->flags; 8602 int ret; 8603 8604 ASSERT_RTNL(); 8605 8606 /* 8607 * Set the flags on our device. 8608 */ 8609 8610 dev->flags = (flags & (IFF_DEBUG | IFF_NOTRAILERS | IFF_NOARP | 8611 IFF_DYNAMIC | IFF_MULTICAST | IFF_PORTSEL | 8612 IFF_AUTOMEDIA)) | 8613 (dev->flags & (IFF_UP | IFF_VOLATILE | IFF_PROMISC | 8614 IFF_ALLMULTI)); 8615 8616 /* 8617 * Load in the correct multicast list now the flags have changed. 8618 */ 8619 8620 if ((old_flags ^ flags) & IFF_MULTICAST) 8621 dev_change_rx_flags(dev, IFF_MULTICAST); 8622 8623 dev_set_rx_mode(dev); 8624 8625 /* 8626 * Have we downed the interface. We handle IFF_UP ourselves 8627 * according to user attempts to set it, rather than blindly 8628 * setting it. 8629 */ 8630 8631 ret = 0; 8632 if ((old_flags ^ flags) & IFF_UP) { 8633 if (old_flags & IFF_UP) 8634 __dev_close(dev); 8635 else 8636 ret = __dev_open(dev, extack); 8637 } 8638 8639 if ((flags ^ dev->gflags) & IFF_PROMISC) { 8640 int inc = (flags & IFF_PROMISC) ? 1 : -1; 8641 unsigned int old_flags = dev->flags; 8642 8643 dev->gflags ^= IFF_PROMISC; 8644 8645 if (__dev_set_promiscuity(dev, inc, false) >= 0) 8646 if (dev->flags != old_flags) 8647 dev_set_rx_mode(dev); 8648 } 8649 8650 /* NOTE: order of synchronization of IFF_PROMISC and IFF_ALLMULTI 8651 * is important. Some (broken) drivers set IFF_PROMISC, when 8652 * IFF_ALLMULTI is requested not asking us and not reporting. 8653 */ 8654 if ((flags ^ dev->gflags) & IFF_ALLMULTI) { 8655 int inc = (flags & IFF_ALLMULTI) ? 1 : -1; 8656 8657 dev->gflags ^= IFF_ALLMULTI; 8658 __dev_set_allmulti(dev, inc, false); 8659 } 8660 8661 return ret; 8662 } 8663 8664 void __dev_notify_flags(struct net_device *dev, unsigned int old_flags, 8665 unsigned int gchanges, u32 portid, 8666 const struct nlmsghdr *nlh) 8667 { 8668 unsigned int changes = dev->flags ^ old_flags; 8669 8670 if (gchanges) 8671 rtmsg_ifinfo(RTM_NEWLINK, dev, gchanges, GFP_ATOMIC, portid, nlh); 8672 8673 if (changes & IFF_UP) { 8674 if (dev->flags & IFF_UP) 8675 call_netdevice_notifiers(NETDEV_UP, dev); 8676 else 8677 call_netdevice_notifiers(NETDEV_DOWN, dev); 8678 } 8679 8680 if (dev->flags & IFF_UP && 8681 (changes & ~(IFF_UP | IFF_PROMISC | IFF_ALLMULTI | IFF_VOLATILE))) { 8682 struct netdev_notifier_change_info change_info = { 8683 .info = { 8684 .dev = dev, 8685 }, 8686 .flags_changed = changes, 8687 }; 8688 8689 call_netdevice_notifiers_info(NETDEV_CHANGE, &change_info.info); 8690 } 8691 } 8692 8693 /** 8694 * dev_change_flags - change device settings 8695 * @dev: device 8696 * @flags: device state flags 8697 * @extack: netlink extended ack 8698 * 8699 * Change settings on device based state flags. The flags are 8700 * in the userspace exported format. 8701 */ 8702 int dev_change_flags(struct net_device *dev, unsigned int flags, 8703 struct netlink_ext_ack *extack) 8704 { 8705 int ret; 8706 unsigned int changes, old_flags = dev->flags, old_gflags = dev->gflags; 8707 8708 ret = __dev_change_flags(dev, flags, extack); 8709 if (ret < 0) 8710 return ret; 8711 8712 changes = (old_flags ^ dev->flags) | (old_gflags ^ dev->gflags); 8713 __dev_notify_flags(dev, old_flags, changes, 0, NULL); 8714 return ret; 8715 } 8716 EXPORT_SYMBOL(dev_change_flags); 8717 8718 int __dev_set_mtu(struct net_device *dev, int new_mtu) 8719 { 8720 const struct net_device_ops *ops = dev->netdev_ops; 8721 8722 if (ops->ndo_change_mtu) 8723 return ops->ndo_change_mtu(dev, new_mtu); 8724 8725 /* Pairs with all the lockless reads of dev->mtu in the stack */ 8726 WRITE_ONCE(dev->mtu, new_mtu); 8727 return 0; 8728 } 8729 EXPORT_SYMBOL(__dev_set_mtu); 8730 8731 int dev_validate_mtu(struct net_device *dev, int new_mtu, 8732 struct netlink_ext_ack *extack) 8733 { 8734 /* MTU must be positive, and in range */ 8735 if (new_mtu < 0 || new_mtu < dev->min_mtu) { 8736 NL_SET_ERR_MSG(extack, "mtu less than device minimum"); 8737 return -EINVAL; 8738 } 8739 8740 if (dev->max_mtu > 0 && new_mtu > dev->max_mtu) { 8741 NL_SET_ERR_MSG(extack, "mtu greater than device maximum"); 8742 return -EINVAL; 8743 } 8744 return 0; 8745 } 8746 8747 /** 8748 * dev_set_mtu_ext - Change maximum transfer unit 8749 * @dev: device 8750 * @new_mtu: new transfer unit 8751 * @extack: netlink extended ack 8752 * 8753 * Change the maximum transfer size of the network device. 8754 */ 8755 int dev_set_mtu_ext(struct net_device *dev, int new_mtu, 8756 struct netlink_ext_ack *extack) 8757 { 8758 int err, orig_mtu; 8759 8760 if (new_mtu == dev->mtu) 8761 return 0; 8762 8763 err = dev_validate_mtu(dev, new_mtu, extack); 8764 if (err) 8765 return err; 8766 8767 if (!netif_device_present(dev)) 8768 return -ENODEV; 8769 8770 err = call_netdevice_notifiers(NETDEV_PRECHANGEMTU, dev); 8771 err = notifier_to_errno(err); 8772 if (err) 8773 return err; 8774 8775 orig_mtu = dev->mtu; 8776 err = __dev_set_mtu(dev, new_mtu); 8777 8778 if (!err) { 8779 err = call_netdevice_notifiers_mtu(NETDEV_CHANGEMTU, dev, 8780 orig_mtu); 8781 err = notifier_to_errno(err); 8782 if (err) { 8783 /* setting mtu back and notifying everyone again, 8784 * so that they have a chance to revert changes. 8785 */ 8786 __dev_set_mtu(dev, orig_mtu); 8787 call_netdevice_notifiers_mtu(NETDEV_CHANGEMTU, dev, 8788 new_mtu); 8789 } 8790 } 8791 return err; 8792 } 8793 8794 int dev_set_mtu(struct net_device *dev, int new_mtu) 8795 { 8796 struct netlink_ext_ack extack; 8797 int err; 8798 8799 memset(&extack, 0, sizeof(extack)); 8800 err = dev_set_mtu_ext(dev, new_mtu, &extack); 8801 if (err && extack._msg) 8802 net_err_ratelimited("%s: %s\n", dev->name, extack._msg); 8803 return err; 8804 } 8805 EXPORT_SYMBOL(dev_set_mtu); 8806 8807 /** 8808 * dev_change_tx_queue_len - Change TX queue length of a netdevice 8809 * @dev: device 8810 * @new_len: new tx queue length 8811 */ 8812 int dev_change_tx_queue_len(struct net_device *dev, unsigned long new_len) 8813 { 8814 unsigned int orig_len = dev->tx_queue_len; 8815 int res; 8816 8817 if (new_len != (unsigned int)new_len) 8818 return -ERANGE; 8819 8820 if (new_len != orig_len) { 8821 dev->tx_queue_len = new_len; 8822 res = call_netdevice_notifiers(NETDEV_CHANGE_TX_QUEUE_LEN, dev); 8823 res = notifier_to_errno(res); 8824 if (res) 8825 goto err_rollback; 8826 res = dev_qdisc_change_tx_queue_len(dev); 8827 if (res) 8828 goto err_rollback; 8829 } 8830 8831 return 0; 8832 8833 err_rollback: 8834 netdev_err(dev, "refused to change device tx_queue_len\n"); 8835 dev->tx_queue_len = orig_len; 8836 return res; 8837 } 8838 8839 /** 8840 * dev_set_group - Change group this device belongs to 8841 * @dev: device 8842 * @new_group: group this device should belong to 8843 */ 8844 void dev_set_group(struct net_device *dev, int new_group) 8845 { 8846 dev->group = new_group; 8847 } 8848 8849 /** 8850 * dev_pre_changeaddr_notify - Call NETDEV_PRE_CHANGEADDR. 8851 * @dev: device 8852 * @addr: new address 8853 * @extack: netlink extended ack 8854 */ 8855 int dev_pre_changeaddr_notify(struct net_device *dev, const char *addr, 8856 struct netlink_ext_ack *extack) 8857 { 8858 struct netdev_notifier_pre_changeaddr_info info = { 8859 .info.dev = dev, 8860 .info.extack = extack, 8861 .dev_addr = addr, 8862 }; 8863 int rc; 8864 8865 rc = call_netdevice_notifiers_info(NETDEV_PRE_CHANGEADDR, &info.info); 8866 return notifier_to_errno(rc); 8867 } 8868 EXPORT_SYMBOL(dev_pre_changeaddr_notify); 8869 8870 /** 8871 * dev_set_mac_address - Change Media Access Control Address 8872 * @dev: device 8873 * @sa: new address 8874 * @extack: netlink extended ack 8875 * 8876 * Change the hardware (MAC) address of the device 8877 */ 8878 int dev_set_mac_address(struct net_device *dev, struct sockaddr *sa, 8879 struct netlink_ext_ack *extack) 8880 { 8881 const struct net_device_ops *ops = dev->netdev_ops; 8882 int err; 8883 8884 if (!ops->ndo_set_mac_address) 8885 return -EOPNOTSUPP; 8886 if (sa->sa_family != dev->type) 8887 return -EINVAL; 8888 if (!netif_device_present(dev)) 8889 return -ENODEV; 8890 err = dev_pre_changeaddr_notify(dev, sa->sa_data, extack); 8891 if (err) 8892 return err; 8893 if (memcmp(dev->dev_addr, sa->sa_data, dev->addr_len)) { 8894 err = ops->ndo_set_mac_address(dev, sa); 8895 if (err) 8896 return err; 8897 } 8898 dev->addr_assign_type = NET_ADDR_SET; 8899 call_netdevice_notifiers(NETDEV_CHANGEADDR, dev); 8900 add_device_randomness(dev->dev_addr, dev->addr_len); 8901 return 0; 8902 } 8903 EXPORT_SYMBOL(dev_set_mac_address); 8904 8905 static DECLARE_RWSEM(dev_addr_sem); 8906 8907 int dev_set_mac_address_user(struct net_device *dev, struct sockaddr *sa, 8908 struct netlink_ext_ack *extack) 8909 { 8910 int ret; 8911 8912 down_write(&dev_addr_sem); 8913 ret = dev_set_mac_address(dev, sa, extack); 8914 up_write(&dev_addr_sem); 8915 return ret; 8916 } 8917 EXPORT_SYMBOL(dev_set_mac_address_user); 8918 8919 int dev_get_mac_address(struct sockaddr *sa, struct net *net, char *dev_name) 8920 { 8921 size_t size = sizeof(sa->sa_data_min); 8922 struct net_device *dev; 8923 int ret = 0; 8924 8925 down_read(&dev_addr_sem); 8926 rcu_read_lock(); 8927 8928 dev = dev_get_by_name_rcu(net, dev_name); 8929 if (!dev) { 8930 ret = -ENODEV; 8931 goto unlock; 8932 } 8933 if (!dev->addr_len) 8934 memset(sa->sa_data, 0, size); 8935 else 8936 memcpy(sa->sa_data, dev->dev_addr, 8937 min_t(size_t, size, dev->addr_len)); 8938 sa->sa_family = dev->type; 8939 8940 unlock: 8941 rcu_read_unlock(); 8942 up_read(&dev_addr_sem); 8943 return ret; 8944 } 8945 EXPORT_SYMBOL(dev_get_mac_address); 8946 8947 /** 8948 * dev_change_carrier - Change device carrier 8949 * @dev: device 8950 * @new_carrier: new value 8951 * 8952 * Change device carrier 8953 */ 8954 int dev_change_carrier(struct net_device *dev, bool new_carrier) 8955 { 8956 const struct net_device_ops *ops = dev->netdev_ops; 8957 8958 if (!ops->ndo_change_carrier) 8959 return -EOPNOTSUPP; 8960 if (!netif_device_present(dev)) 8961 return -ENODEV; 8962 return ops->ndo_change_carrier(dev, new_carrier); 8963 } 8964 8965 /** 8966 * dev_get_phys_port_id - Get device physical port ID 8967 * @dev: device 8968 * @ppid: port ID 8969 * 8970 * Get device physical port ID 8971 */ 8972 int dev_get_phys_port_id(struct net_device *dev, 8973 struct netdev_phys_item_id *ppid) 8974 { 8975 const struct net_device_ops *ops = dev->netdev_ops; 8976 8977 if (!ops->ndo_get_phys_port_id) 8978 return -EOPNOTSUPP; 8979 return ops->ndo_get_phys_port_id(dev, ppid); 8980 } 8981 8982 /** 8983 * dev_get_phys_port_name - Get device physical port name 8984 * @dev: device 8985 * @name: port name 8986 * @len: limit of bytes to copy to name 8987 * 8988 * Get device physical port name 8989 */ 8990 int dev_get_phys_port_name(struct net_device *dev, 8991 char *name, size_t len) 8992 { 8993 const struct net_device_ops *ops = dev->netdev_ops; 8994 int err; 8995 8996 if (ops->ndo_get_phys_port_name) { 8997 err = ops->ndo_get_phys_port_name(dev, name, len); 8998 if (err != -EOPNOTSUPP) 8999 return err; 9000 } 9001 return devlink_compat_phys_port_name_get(dev, name, len); 9002 } 9003 9004 /** 9005 * dev_get_port_parent_id - Get the device's port parent identifier 9006 * @dev: network device 9007 * @ppid: pointer to a storage for the port's parent identifier 9008 * @recurse: allow/disallow recursion to lower devices 9009 * 9010 * Get the devices's port parent identifier 9011 */ 9012 int dev_get_port_parent_id(struct net_device *dev, 9013 struct netdev_phys_item_id *ppid, 9014 bool recurse) 9015 { 9016 const struct net_device_ops *ops = dev->netdev_ops; 9017 struct netdev_phys_item_id first = { }; 9018 struct net_device *lower_dev; 9019 struct list_head *iter; 9020 int err; 9021 9022 if (ops->ndo_get_port_parent_id) { 9023 err = ops->ndo_get_port_parent_id(dev, ppid); 9024 if (err != -EOPNOTSUPP) 9025 return err; 9026 } 9027 9028 err = devlink_compat_switch_id_get(dev, ppid); 9029 if (!recurse || err != -EOPNOTSUPP) 9030 return err; 9031 9032 netdev_for_each_lower_dev(dev, lower_dev, iter) { 9033 err = dev_get_port_parent_id(lower_dev, ppid, true); 9034 if (err) 9035 break; 9036 if (!first.id_len) 9037 first = *ppid; 9038 else if (memcmp(&first, ppid, sizeof(*ppid))) 9039 return -EOPNOTSUPP; 9040 } 9041 9042 return err; 9043 } 9044 EXPORT_SYMBOL(dev_get_port_parent_id); 9045 9046 /** 9047 * netdev_port_same_parent_id - Indicate if two network devices have 9048 * the same port parent identifier 9049 * @a: first network device 9050 * @b: second network device 9051 */ 9052 bool netdev_port_same_parent_id(struct net_device *a, struct net_device *b) 9053 { 9054 struct netdev_phys_item_id a_id = { }; 9055 struct netdev_phys_item_id b_id = { }; 9056 9057 if (dev_get_port_parent_id(a, &a_id, true) || 9058 dev_get_port_parent_id(b, &b_id, true)) 9059 return false; 9060 9061 return netdev_phys_item_id_same(&a_id, &b_id); 9062 } 9063 EXPORT_SYMBOL(netdev_port_same_parent_id); 9064 9065 /** 9066 * dev_change_proto_down - set carrier according to proto_down. 9067 * 9068 * @dev: device 9069 * @proto_down: new value 9070 */ 9071 int dev_change_proto_down(struct net_device *dev, bool proto_down) 9072 { 9073 if (!(dev->priv_flags & IFF_CHANGE_PROTO_DOWN)) 9074 return -EOPNOTSUPP; 9075 if (!netif_device_present(dev)) 9076 return -ENODEV; 9077 if (proto_down) 9078 netif_carrier_off(dev); 9079 else 9080 netif_carrier_on(dev); 9081 dev->proto_down = proto_down; 9082 return 0; 9083 } 9084 9085 /** 9086 * dev_change_proto_down_reason - proto down reason 9087 * 9088 * @dev: device 9089 * @mask: proto down mask 9090 * @value: proto down value 9091 */ 9092 void dev_change_proto_down_reason(struct net_device *dev, unsigned long mask, 9093 u32 value) 9094 { 9095 int b; 9096 9097 if (!mask) { 9098 dev->proto_down_reason = value; 9099 } else { 9100 for_each_set_bit(b, &mask, 32) { 9101 if (value & (1 << b)) 9102 dev->proto_down_reason |= BIT(b); 9103 else 9104 dev->proto_down_reason &= ~BIT(b); 9105 } 9106 } 9107 } 9108 9109 struct bpf_xdp_link { 9110 struct bpf_link link; 9111 struct net_device *dev; /* protected by rtnl_lock, no refcnt held */ 9112 int flags; 9113 }; 9114 9115 static enum bpf_xdp_mode dev_xdp_mode(struct net_device *dev, u32 flags) 9116 { 9117 if (flags & XDP_FLAGS_HW_MODE) 9118 return XDP_MODE_HW; 9119 if (flags & XDP_FLAGS_DRV_MODE) 9120 return XDP_MODE_DRV; 9121 if (flags & XDP_FLAGS_SKB_MODE) 9122 return XDP_MODE_SKB; 9123 return dev->netdev_ops->ndo_bpf ? XDP_MODE_DRV : XDP_MODE_SKB; 9124 } 9125 9126 static bpf_op_t dev_xdp_bpf_op(struct net_device *dev, enum bpf_xdp_mode mode) 9127 { 9128 switch (mode) { 9129 case XDP_MODE_SKB: 9130 return generic_xdp_install; 9131 case XDP_MODE_DRV: 9132 case XDP_MODE_HW: 9133 return dev->netdev_ops->ndo_bpf; 9134 default: 9135 return NULL; 9136 } 9137 } 9138 9139 static struct bpf_xdp_link *dev_xdp_link(struct net_device *dev, 9140 enum bpf_xdp_mode mode) 9141 { 9142 return dev->xdp_state[mode].link; 9143 } 9144 9145 static struct bpf_prog *dev_xdp_prog(struct net_device *dev, 9146 enum bpf_xdp_mode mode) 9147 { 9148 struct bpf_xdp_link *link = dev_xdp_link(dev, mode); 9149 9150 if (link) 9151 return link->link.prog; 9152 return dev->xdp_state[mode].prog; 9153 } 9154 9155 u8 dev_xdp_prog_count(struct net_device *dev) 9156 { 9157 u8 count = 0; 9158 int i; 9159 9160 for (i = 0; i < __MAX_XDP_MODE; i++) 9161 if (dev->xdp_state[i].prog || dev->xdp_state[i].link) 9162 count++; 9163 return count; 9164 } 9165 EXPORT_SYMBOL_GPL(dev_xdp_prog_count); 9166 9167 u32 dev_xdp_prog_id(struct net_device *dev, enum bpf_xdp_mode mode) 9168 { 9169 struct bpf_prog *prog = dev_xdp_prog(dev, mode); 9170 9171 return prog ? prog->aux->id : 0; 9172 } 9173 9174 static void dev_xdp_set_link(struct net_device *dev, enum bpf_xdp_mode mode, 9175 struct bpf_xdp_link *link) 9176 { 9177 dev->xdp_state[mode].link = link; 9178 dev->xdp_state[mode].prog = NULL; 9179 } 9180 9181 static void dev_xdp_set_prog(struct net_device *dev, enum bpf_xdp_mode mode, 9182 struct bpf_prog *prog) 9183 { 9184 dev->xdp_state[mode].link = NULL; 9185 dev->xdp_state[mode].prog = prog; 9186 } 9187 9188 static int dev_xdp_install(struct net_device *dev, enum bpf_xdp_mode mode, 9189 bpf_op_t bpf_op, struct netlink_ext_ack *extack, 9190 u32 flags, struct bpf_prog *prog) 9191 { 9192 struct netdev_bpf xdp; 9193 int err; 9194 9195 memset(&xdp, 0, sizeof(xdp)); 9196 xdp.command = mode == XDP_MODE_HW ? XDP_SETUP_PROG_HW : XDP_SETUP_PROG; 9197 xdp.extack = extack; 9198 xdp.flags = flags; 9199 xdp.prog = prog; 9200 9201 /* Drivers assume refcnt is already incremented (i.e, prog pointer is 9202 * "moved" into driver), so they don't increment it on their own, but 9203 * they do decrement refcnt when program is detached or replaced. 9204 * Given net_device also owns link/prog, we need to bump refcnt here 9205 * to prevent drivers from underflowing it. 9206 */ 9207 if (prog) 9208 bpf_prog_inc(prog); 9209 err = bpf_op(dev, &xdp); 9210 if (err) { 9211 if (prog) 9212 bpf_prog_put(prog); 9213 return err; 9214 } 9215 9216 if (mode != XDP_MODE_HW) 9217 bpf_prog_change_xdp(dev_xdp_prog(dev, mode), prog); 9218 9219 return 0; 9220 } 9221 9222 static void dev_xdp_uninstall(struct net_device *dev) 9223 { 9224 struct bpf_xdp_link *link; 9225 struct bpf_prog *prog; 9226 enum bpf_xdp_mode mode; 9227 bpf_op_t bpf_op; 9228 9229 ASSERT_RTNL(); 9230 9231 for (mode = XDP_MODE_SKB; mode < __MAX_XDP_MODE; mode++) { 9232 prog = dev_xdp_prog(dev, mode); 9233 if (!prog) 9234 continue; 9235 9236 bpf_op = dev_xdp_bpf_op(dev, mode); 9237 if (!bpf_op) 9238 continue; 9239 9240 WARN_ON(dev_xdp_install(dev, mode, bpf_op, NULL, 0, NULL)); 9241 9242 /* auto-detach link from net device */ 9243 link = dev_xdp_link(dev, mode); 9244 if (link) 9245 link->dev = NULL; 9246 else 9247 bpf_prog_put(prog); 9248 9249 dev_xdp_set_link(dev, mode, NULL); 9250 } 9251 } 9252 9253 static int dev_xdp_attach(struct net_device *dev, struct netlink_ext_ack *extack, 9254 struct bpf_xdp_link *link, struct bpf_prog *new_prog, 9255 struct bpf_prog *old_prog, u32 flags) 9256 { 9257 unsigned int num_modes = hweight32(flags & XDP_FLAGS_MODES); 9258 struct bpf_prog *cur_prog; 9259 struct net_device *upper; 9260 struct list_head *iter; 9261 enum bpf_xdp_mode mode; 9262 bpf_op_t bpf_op; 9263 int err; 9264 9265 ASSERT_RTNL(); 9266 9267 /* either link or prog attachment, never both */ 9268 if (link && (new_prog || old_prog)) 9269 return -EINVAL; 9270 /* link supports only XDP mode flags */ 9271 if (link && (flags & ~XDP_FLAGS_MODES)) { 9272 NL_SET_ERR_MSG(extack, "Invalid XDP flags for BPF link attachment"); 9273 return -EINVAL; 9274 } 9275 /* just one XDP mode bit should be set, zero defaults to drv/skb mode */ 9276 if (num_modes > 1) { 9277 NL_SET_ERR_MSG(extack, "Only one XDP mode flag can be set"); 9278 return -EINVAL; 9279 } 9280 /* avoid ambiguity if offload + drv/skb mode progs are both loaded */ 9281 if (!num_modes && dev_xdp_prog_count(dev) > 1) { 9282 NL_SET_ERR_MSG(extack, 9283 "More than one program loaded, unset mode is ambiguous"); 9284 return -EINVAL; 9285 } 9286 /* old_prog != NULL implies XDP_FLAGS_REPLACE is set */ 9287 if (old_prog && !(flags & XDP_FLAGS_REPLACE)) { 9288 NL_SET_ERR_MSG(extack, "XDP_FLAGS_REPLACE is not specified"); 9289 return -EINVAL; 9290 } 9291 9292 mode = dev_xdp_mode(dev, flags); 9293 /* can't replace attached link */ 9294 if (dev_xdp_link(dev, mode)) { 9295 NL_SET_ERR_MSG(extack, "Can't replace active BPF XDP link"); 9296 return -EBUSY; 9297 } 9298 9299 /* don't allow if an upper device already has a program */ 9300 netdev_for_each_upper_dev_rcu(dev, upper, iter) { 9301 if (dev_xdp_prog_count(upper) > 0) { 9302 NL_SET_ERR_MSG(extack, "Cannot attach when an upper device already has a program"); 9303 return -EEXIST; 9304 } 9305 } 9306 9307 cur_prog = dev_xdp_prog(dev, mode); 9308 /* can't replace attached prog with link */ 9309 if (link && cur_prog) { 9310 NL_SET_ERR_MSG(extack, "Can't replace active XDP program with BPF link"); 9311 return -EBUSY; 9312 } 9313 if ((flags & XDP_FLAGS_REPLACE) && cur_prog != old_prog) { 9314 NL_SET_ERR_MSG(extack, "Active program does not match expected"); 9315 return -EEXIST; 9316 } 9317 9318 /* put effective new program into new_prog */ 9319 if (link) 9320 new_prog = link->link.prog; 9321 9322 if (new_prog) { 9323 bool offload = mode == XDP_MODE_HW; 9324 enum bpf_xdp_mode other_mode = mode == XDP_MODE_SKB 9325 ? XDP_MODE_DRV : XDP_MODE_SKB; 9326 9327 if ((flags & XDP_FLAGS_UPDATE_IF_NOEXIST) && cur_prog) { 9328 NL_SET_ERR_MSG(extack, "XDP program already attached"); 9329 return -EBUSY; 9330 } 9331 if (!offload && dev_xdp_prog(dev, other_mode)) { 9332 NL_SET_ERR_MSG(extack, "Native and generic XDP can't be active at the same time"); 9333 return -EEXIST; 9334 } 9335 if (!offload && bpf_prog_is_offloaded(new_prog->aux)) { 9336 NL_SET_ERR_MSG(extack, "Using offloaded program without HW_MODE flag is not supported"); 9337 return -EINVAL; 9338 } 9339 if (bpf_prog_is_dev_bound(new_prog->aux) && !bpf_offload_dev_match(new_prog, dev)) { 9340 NL_SET_ERR_MSG(extack, "Program bound to different device"); 9341 return -EINVAL; 9342 } 9343 if (new_prog->expected_attach_type == BPF_XDP_DEVMAP) { 9344 NL_SET_ERR_MSG(extack, "BPF_XDP_DEVMAP programs can not be attached to a device"); 9345 return -EINVAL; 9346 } 9347 if (new_prog->expected_attach_type == BPF_XDP_CPUMAP) { 9348 NL_SET_ERR_MSG(extack, "BPF_XDP_CPUMAP programs can not be attached to a device"); 9349 return -EINVAL; 9350 } 9351 } 9352 9353 /* don't call drivers if the effective program didn't change */ 9354 if (new_prog != cur_prog) { 9355 bpf_op = dev_xdp_bpf_op(dev, mode); 9356 if (!bpf_op) { 9357 NL_SET_ERR_MSG(extack, "Underlying driver does not support XDP in native mode"); 9358 return -EOPNOTSUPP; 9359 } 9360 9361 err = dev_xdp_install(dev, mode, bpf_op, extack, flags, new_prog); 9362 if (err) 9363 return err; 9364 } 9365 9366 if (link) 9367 dev_xdp_set_link(dev, mode, link); 9368 else 9369 dev_xdp_set_prog(dev, mode, new_prog); 9370 if (cur_prog) 9371 bpf_prog_put(cur_prog); 9372 9373 return 0; 9374 } 9375 9376 static int dev_xdp_attach_link(struct net_device *dev, 9377 struct netlink_ext_ack *extack, 9378 struct bpf_xdp_link *link) 9379 { 9380 return dev_xdp_attach(dev, extack, link, NULL, NULL, link->flags); 9381 } 9382 9383 static int dev_xdp_detach_link(struct net_device *dev, 9384 struct netlink_ext_ack *extack, 9385 struct bpf_xdp_link *link) 9386 { 9387 enum bpf_xdp_mode mode; 9388 bpf_op_t bpf_op; 9389 9390 ASSERT_RTNL(); 9391 9392 mode = dev_xdp_mode(dev, link->flags); 9393 if (dev_xdp_link(dev, mode) != link) 9394 return -EINVAL; 9395 9396 bpf_op = dev_xdp_bpf_op(dev, mode); 9397 WARN_ON(dev_xdp_install(dev, mode, bpf_op, NULL, 0, NULL)); 9398 dev_xdp_set_link(dev, mode, NULL); 9399 return 0; 9400 } 9401 9402 static void bpf_xdp_link_release(struct bpf_link *link) 9403 { 9404 struct bpf_xdp_link *xdp_link = container_of(link, struct bpf_xdp_link, link); 9405 9406 rtnl_lock(); 9407 9408 /* if racing with net_device's tear down, xdp_link->dev might be 9409 * already NULL, in which case link was already auto-detached 9410 */ 9411 if (xdp_link->dev) { 9412 WARN_ON(dev_xdp_detach_link(xdp_link->dev, NULL, xdp_link)); 9413 xdp_link->dev = NULL; 9414 } 9415 9416 rtnl_unlock(); 9417 } 9418 9419 static int bpf_xdp_link_detach(struct bpf_link *link) 9420 { 9421 bpf_xdp_link_release(link); 9422 return 0; 9423 } 9424 9425 static void bpf_xdp_link_dealloc(struct bpf_link *link) 9426 { 9427 struct bpf_xdp_link *xdp_link = container_of(link, struct bpf_xdp_link, link); 9428 9429 kfree(xdp_link); 9430 } 9431 9432 static void bpf_xdp_link_show_fdinfo(const struct bpf_link *link, 9433 struct seq_file *seq) 9434 { 9435 struct bpf_xdp_link *xdp_link = container_of(link, struct bpf_xdp_link, link); 9436 u32 ifindex = 0; 9437 9438 rtnl_lock(); 9439 if (xdp_link->dev) 9440 ifindex = xdp_link->dev->ifindex; 9441 rtnl_unlock(); 9442 9443 seq_printf(seq, "ifindex:\t%u\n", ifindex); 9444 } 9445 9446 static int bpf_xdp_link_fill_link_info(const struct bpf_link *link, 9447 struct bpf_link_info *info) 9448 { 9449 struct bpf_xdp_link *xdp_link = container_of(link, struct bpf_xdp_link, link); 9450 u32 ifindex = 0; 9451 9452 rtnl_lock(); 9453 if (xdp_link->dev) 9454 ifindex = xdp_link->dev->ifindex; 9455 rtnl_unlock(); 9456 9457 info->xdp.ifindex = ifindex; 9458 return 0; 9459 } 9460 9461 static int bpf_xdp_link_update(struct bpf_link *link, struct bpf_prog *new_prog, 9462 struct bpf_prog *old_prog) 9463 { 9464 struct bpf_xdp_link *xdp_link = container_of(link, struct bpf_xdp_link, link); 9465 enum bpf_xdp_mode mode; 9466 bpf_op_t bpf_op; 9467 int err = 0; 9468 9469 rtnl_lock(); 9470 9471 /* link might have been auto-released already, so fail */ 9472 if (!xdp_link->dev) { 9473 err = -ENOLINK; 9474 goto out_unlock; 9475 } 9476 9477 if (old_prog && link->prog != old_prog) { 9478 err = -EPERM; 9479 goto out_unlock; 9480 } 9481 old_prog = link->prog; 9482 if (old_prog->type != new_prog->type || 9483 old_prog->expected_attach_type != new_prog->expected_attach_type) { 9484 err = -EINVAL; 9485 goto out_unlock; 9486 } 9487 9488 if (old_prog == new_prog) { 9489 /* no-op, don't disturb drivers */ 9490 bpf_prog_put(new_prog); 9491 goto out_unlock; 9492 } 9493 9494 mode = dev_xdp_mode(xdp_link->dev, xdp_link->flags); 9495 bpf_op = dev_xdp_bpf_op(xdp_link->dev, mode); 9496 err = dev_xdp_install(xdp_link->dev, mode, bpf_op, NULL, 9497 xdp_link->flags, new_prog); 9498 if (err) 9499 goto out_unlock; 9500 9501 old_prog = xchg(&link->prog, new_prog); 9502 bpf_prog_put(old_prog); 9503 9504 out_unlock: 9505 rtnl_unlock(); 9506 return err; 9507 } 9508 9509 static const struct bpf_link_ops bpf_xdp_link_lops = { 9510 .release = bpf_xdp_link_release, 9511 .dealloc = bpf_xdp_link_dealloc, 9512 .detach = bpf_xdp_link_detach, 9513 .show_fdinfo = bpf_xdp_link_show_fdinfo, 9514 .fill_link_info = bpf_xdp_link_fill_link_info, 9515 .update_prog = bpf_xdp_link_update, 9516 }; 9517 9518 int bpf_xdp_link_attach(const union bpf_attr *attr, struct bpf_prog *prog) 9519 { 9520 struct net *net = current->nsproxy->net_ns; 9521 struct bpf_link_primer link_primer; 9522 struct netlink_ext_ack extack = {}; 9523 struct bpf_xdp_link *link; 9524 struct net_device *dev; 9525 int err, fd; 9526 9527 rtnl_lock(); 9528 dev = dev_get_by_index(net, attr->link_create.target_ifindex); 9529 if (!dev) { 9530 rtnl_unlock(); 9531 return -EINVAL; 9532 } 9533 9534 link = kzalloc(sizeof(*link), GFP_USER); 9535 if (!link) { 9536 err = -ENOMEM; 9537 goto unlock; 9538 } 9539 9540 bpf_link_init(&link->link, BPF_LINK_TYPE_XDP, &bpf_xdp_link_lops, prog); 9541 link->dev = dev; 9542 link->flags = attr->link_create.flags; 9543 9544 err = bpf_link_prime(&link->link, &link_primer); 9545 if (err) { 9546 kfree(link); 9547 goto unlock; 9548 } 9549 9550 err = dev_xdp_attach_link(dev, &extack, link); 9551 rtnl_unlock(); 9552 9553 if (err) { 9554 link->dev = NULL; 9555 bpf_link_cleanup(&link_primer); 9556 trace_bpf_xdp_link_attach_failed(extack._msg); 9557 goto out_put_dev; 9558 } 9559 9560 fd = bpf_link_settle(&link_primer); 9561 /* link itself doesn't hold dev's refcnt to not complicate shutdown */ 9562 dev_put(dev); 9563 return fd; 9564 9565 unlock: 9566 rtnl_unlock(); 9567 9568 out_put_dev: 9569 dev_put(dev); 9570 return err; 9571 } 9572 9573 /** 9574 * dev_change_xdp_fd - set or clear a bpf program for a device rx path 9575 * @dev: device 9576 * @extack: netlink extended ack 9577 * @fd: new program fd or negative value to clear 9578 * @expected_fd: old program fd that userspace expects to replace or clear 9579 * @flags: xdp-related flags 9580 * 9581 * Set or clear a bpf program for a device 9582 */ 9583 int dev_change_xdp_fd(struct net_device *dev, struct netlink_ext_ack *extack, 9584 int fd, int expected_fd, u32 flags) 9585 { 9586 enum bpf_xdp_mode mode = dev_xdp_mode(dev, flags); 9587 struct bpf_prog *new_prog = NULL, *old_prog = NULL; 9588 int err; 9589 9590 ASSERT_RTNL(); 9591 9592 if (fd >= 0) { 9593 new_prog = bpf_prog_get_type_dev(fd, BPF_PROG_TYPE_XDP, 9594 mode != XDP_MODE_SKB); 9595 if (IS_ERR(new_prog)) 9596 return PTR_ERR(new_prog); 9597 } 9598 9599 if (expected_fd >= 0) { 9600 old_prog = bpf_prog_get_type_dev(expected_fd, BPF_PROG_TYPE_XDP, 9601 mode != XDP_MODE_SKB); 9602 if (IS_ERR(old_prog)) { 9603 err = PTR_ERR(old_prog); 9604 old_prog = NULL; 9605 goto err_out; 9606 } 9607 } 9608 9609 err = dev_xdp_attach(dev, extack, NULL, new_prog, old_prog, flags); 9610 9611 err_out: 9612 if (err && new_prog) 9613 bpf_prog_put(new_prog); 9614 if (old_prog) 9615 bpf_prog_put(old_prog); 9616 return err; 9617 } 9618 9619 /** 9620 * dev_index_reserve() - allocate an ifindex in a namespace 9621 * @net: the applicable net namespace 9622 * @ifindex: requested ifindex, pass %0 to get one allocated 9623 * 9624 * Allocate a ifindex for a new device. Caller must either use the ifindex 9625 * to store the device (via list_netdevice()) or call dev_index_release() 9626 * to give the index up. 9627 * 9628 * Return: a suitable unique value for a new device interface number or -errno. 9629 */ 9630 static int dev_index_reserve(struct net *net, u32 ifindex) 9631 { 9632 int err; 9633 9634 if (ifindex > INT_MAX) { 9635 DEBUG_NET_WARN_ON_ONCE(1); 9636 return -EINVAL; 9637 } 9638 9639 if (!ifindex) 9640 err = xa_alloc_cyclic(&net->dev_by_index, &ifindex, NULL, 9641 xa_limit_31b, &net->ifindex, GFP_KERNEL); 9642 else 9643 err = xa_insert(&net->dev_by_index, ifindex, NULL, GFP_KERNEL); 9644 if (err < 0) 9645 return err; 9646 9647 return ifindex; 9648 } 9649 9650 static void dev_index_release(struct net *net, int ifindex) 9651 { 9652 /* Expect only unused indexes, unlist_netdevice() removes the used */ 9653 WARN_ON(xa_erase(&net->dev_by_index, ifindex)); 9654 } 9655 9656 /* Delayed registration/unregisteration */ 9657 LIST_HEAD(net_todo_list); 9658 DECLARE_WAIT_QUEUE_HEAD(netdev_unregistering_wq); 9659 9660 static void net_set_todo(struct net_device *dev) 9661 { 9662 list_add_tail(&dev->todo_list, &net_todo_list); 9663 atomic_inc(&dev_net(dev)->dev_unreg_count); 9664 } 9665 9666 static netdev_features_t netdev_sync_upper_features(struct net_device *lower, 9667 struct net_device *upper, netdev_features_t features) 9668 { 9669 netdev_features_t upper_disables = NETIF_F_UPPER_DISABLES; 9670 netdev_features_t feature; 9671 int feature_bit; 9672 9673 for_each_netdev_feature(upper_disables, feature_bit) { 9674 feature = __NETIF_F_BIT(feature_bit); 9675 if (!(upper->wanted_features & feature) 9676 && (features & feature)) { 9677 netdev_dbg(lower, "Dropping feature %pNF, upper dev %s has it off.\n", 9678 &feature, upper->name); 9679 features &= ~feature; 9680 } 9681 } 9682 9683 return features; 9684 } 9685 9686 static void netdev_sync_lower_features(struct net_device *upper, 9687 struct net_device *lower, netdev_features_t features) 9688 { 9689 netdev_features_t upper_disables = NETIF_F_UPPER_DISABLES; 9690 netdev_features_t feature; 9691 int feature_bit; 9692 9693 for_each_netdev_feature(upper_disables, feature_bit) { 9694 feature = __NETIF_F_BIT(feature_bit); 9695 if (!(features & feature) && (lower->features & feature)) { 9696 netdev_dbg(upper, "Disabling feature %pNF on lower dev %s.\n", 9697 &feature, lower->name); 9698 lower->wanted_features &= ~feature; 9699 __netdev_update_features(lower); 9700 9701 if (unlikely(lower->features & feature)) 9702 netdev_WARN(upper, "failed to disable %pNF on %s!\n", 9703 &feature, lower->name); 9704 else 9705 netdev_features_change(lower); 9706 } 9707 } 9708 } 9709 9710 static netdev_features_t netdev_fix_features(struct net_device *dev, 9711 netdev_features_t features) 9712 { 9713 /* Fix illegal checksum combinations */ 9714 if ((features & NETIF_F_HW_CSUM) && 9715 (features & (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))) { 9716 netdev_warn(dev, "mixed HW and IP checksum settings.\n"); 9717 features &= ~(NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM); 9718 } 9719 9720 /* TSO requires that SG is present as well. */ 9721 if ((features & NETIF_F_ALL_TSO) && !(features & NETIF_F_SG)) { 9722 netdev_dbg(dev, "Dropping TSO features since no SG feature.\n"); 9723 features &= ~NETIF_F_ALL_TSO; 9724 } 9725 9726 if ((features & NETIF_F_TSO) && !(features & NETIF_F_HW_CSUM) && 9727 !(features & NETIF_F_IP_CSUM)) { 9728 netdev_dbg(dev, "Dropping TSO features since no CSUM feature.\n"); 9729 features &= ~NETIF_F_TSO; 9730 features &= ~NETIF_F_TSO_ECN; 9731 } 9732 9733 if ((features & NETIF_F_TSO6) && !(features & NETIF_F_HW_CSUM) && 9734 !(features & NETIF_F_IPV6_CSUM)) { 9735 netdev_dbg(dev, "Dropping TSO6 features since no CSUM feature.\n"); 9736 features &= ~NETIF_F_TSO6; 9737 } 9738 9739 /* TSO with IPv4 ID mangling requires IPv4 TSO be enabled */ 9740 if ((features & NETIF_F_TSO_MANGLEID) && !(features & NETIF_F_TSO)) 9741 features &= ~NETIF_F_TSO_MANGLEID; 9742 9743 /* TSO ECN requires that TSO is present as well. */ 9744 if ((features & NETIF_F_ALL_TSO) == NETIF_F_TSO_ECN) 9745 features &= ~NETIF_F_TSO_ECN; 9746 9747 /* Software GSO depends on SG. */ 9748 if ((features & NETIF_F_GSO) && !(features & NETIF_F_SG)) { 9749 netdev_dbg(dev, "Dropping NETIF_F_GSO since no SG feature.\n"); 9750 features &= ~NETIF_F_GSO; 9751 } 9752 9753 /* GSO partial features require GSO partial be set */ 9754 if ((features & dev->gso_partial_features) && 9755 !(features & NETIF_F_GSO_PARTIAL)) { 9756 netdev_dbg(dev, 9757 "Dropping partially supported GSO features since no GSO partial.\n"); 9758 features &= ~dev->gso_partial_features; 9759 } 9760 9761 if (!(features & NETIF_F_RXCSUM)) { 9762 /* NETIF_F_GRO_HW implies doing RXCSUM since every packet 9763 * successfully merged by hardware must also have the 9764 * checksum verified by hardware. If the user does not 9765 * want to enable RXCSUM, logically, we should disable GRO_HW. 9766 */ 9767 if (features & NETIF_F_GRO_HW) { 9768 netdev_dbg(dev, "Dropping NETIF_F_GRO_HW since no RXCSUM feature.\n"); 9769 features &= ~NETIF_F_GRO_HW; 9770 } 9771 } 9772 9773 /* LRO/HW-GRO features cannot be combined with RX-FCS */ 9774 if (features & NETIF_F_RXFCS) { 9775 if (features & NETIF_F_LRO) { 9776 netdev_dbg(dev, "Dropping LRO feature since RX-FCS is requested.\n"); 9777 features &= ~NETIF_F_LRO; 9778 } 9779 9780 if (features & NETIF_F_GRO_HW) { 9781 netdev_dbg(dev, "Dropping HW-GRO feature since RX-FCS is requested.\n"); 9782 features &= ~NETIF_F_GRO_HW; 9783 } 9784 } 9785 9786 if ((features & NETIF_F_GRO_HW) && (features & NETIF_F_LRO)) { 9787 netdev_dbg(dev, "Dropping LRO feature since HW-GRO is requested.\n"); 9788 features &= ~NETIF_F_LRO; 9789 } 9790 9791 if (features & NETIF_F_HW_TLS_TX) { 9792 bool ip_csum = (features & (NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM)) == 9793 (NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM); 9794 bool hw_csum = features & NETIF_F_HW_CSUM; 9795 9796 if (!ip_csum && !hw_csum) { 9797 netdev_dbg(dev, "Dropping TLS TX HW offload feature since no CSUM feature.\n"); 9798 features &= ~NETIF_F_HW_TLS_TX; 9799 } 9800 } 9801 9802 if ((features & NETIF_F_HW_TLS_RX) && !(features & NETIF_F_RXCSUM)) { 9803 netdev_dbg(dev, "Dropping TLS RX HW offload feature since no RXCSUM feature.\n"); 9804 features &= ~NETIF_F_HW_TLS_RX; 9805 } 9806 9807 return features; 9808 } 9809 9810 int __netdev_update_features(struct net_device *dev) 9811 { 9812 struct net_device *upper, *lower; 9813 netdev_features_t features; 9814 struct list_head *iter; 9815 int err = -1; 9816 9817 ASSERT_RTNL(); 9818 9819 features = netdev_get_wanted_features(dev); 9820 9821 if (dev->netdev_ops->ndo_fix_features) 9822 features = dev->netdev_ops->ndo_fix_features(dev, features); 9823 9824 /* driver might be less strict about feature dependencies */ 9825 features = netdev_fix_features(dev, features); 9826 9827 /* some features can't be enabled if they're off on an upper device */ 9828 netdev_for_each_upper_dev_rcu(dev, upper, iter) 9829 features = netdev_sync_upper_features(dev, upper, features); 9830 9831 if (dev->features == features) 9832 goto sync_lower; 9833 9834 netdev_dbg(dev, "Features changed: %pNF -> %pNF\n", 9835 &dev->features, &features); 9836 9837 if (dev->netdev_ops->ndo_set_features) 9838 err = dev->netdev_ops->ndo_set_features(dev, features); 9839 else 9840 err = 0; 9841 9842 if (unlikely(err < 0)) { 9843 netdev_err(dev, 9844 "set_features() failed (%d); wanted %pNF, left %pNF\n", 9845 err, &features, &dev->features); 9846 /* return non-0 since some features might have changed and 9847 * it's better to fire a spurious notification than miss it 9848 */ 9849 return -1; 9850 } 9851 9852 sync_lower: 9853 /* some features must be disabled on lower devices when disabled 9854 * on an upper device (think: bonding master or bridge) 9855 */ 9856 netdev_for_each_lower_dev(dev, lower, iter) 9857 netdev_sync_lower_features(dev, lower, features); 9858 9859 if (!err) { 9860 netdev_features_t diff = features ^ dev->features; 9861 9862 if (diff & NETIF_F_RX_UDP_TUNNEL_PORT) { 9863 /* udp_tunnel_{get,drop}_rx_info both need 9864 * NETIF_F_RX_UDP_TUNNEL_PORT enabled on the 9865 * device, or they won't do anything. 9866 * Thus we need to update dev->features 9867 * *before* calling udp_tunnel_get_rx_info, 9868 * but *after* calling udp_tunnel_drop_rx_info. 9869 */ 9870 if (features & NETIF_F_RX_UDP_TUNNEL_PORT) { 9871 dev->features = features; 9872 udp_tunnel_get_rx_info(dev); 9873 } else { 9874 udp_tunnel_drop_rx_info(dev); 9875 } 9876 } 9877 9878 if (diff & NETIF_F_HW_VLAN_CTAG_FILTER) { 9879 if (features & NETIF_F_HW_VLAN_CTAG_FILTER) { 9880 dev->features = features; 9881 err |= vlan_get_rx_ctag_filter_info(dev); 9882 } else { 9883 vlan_drop_rx_ctag_filter_info(dev); 9884 } 9885 } 9886 9887 if (diff & NETIF_F_HW_VLAN_STAG_FILTER) { 9888 if (features & NETIF_F_HW_VLAN_STAG_FILTER) { 9889 dev->features = features; 9890 err |= vlan_get_rx_stag_filter_info(dev); 9891 } else { 9892 vlan_drop_rx_stag_filter_info(dev); 9893 } 9894 } 9895 9896 dev->features = features; 9897 } 9898 9899 return err < 0 ? 0 : 1; 9900 } 9901 9902 /** 9903 * netdev_update_features - recalculate device features 9904 * @dev: the device to check 9905 * 9906 * Recalculate dev->features set and send notifications if it 9907 * has changed. Should be called after driver or hardware dependent 9908 * conditions might have changed that influence the features. 9909 */ 9910 void netdev_update_features(struct net_device *dev) 9911 { 9912 if (__netdev_update_features(dev)) 9913 netdev_features_change(dev); 9914 } 9915 EXPORT_SYMBOL(netdev_update_features); 9916 9917 /** 9918 * netdev_change_features - recalculate device features 9919 * @dev: the device to check 9920 * 9921 * Recalculate dev->features set and send notifications even 9922 * if they have not changed. Should be called instead of 9923 * netdev_update_features() if also dev->vlan_features might 9924 * have changed to allow the changes to be propagated to stacked 9925 * VLAN devices. 9926 */ 9927 void netdev_change_features(struct net_device *dev) 9928 { 9929 __netdev_update_features(dev); 9930 netdev_features_change(dev); 9931 } 9932 EXPORT_SYMBOL(netdev_change_features); 9933 9934 /** 9935 * netif_stacked_transfer_operstate - transfer operstate 9936 * @rootdev: the root or lower level device to transfer state from 9937 * @dev: the device to transfer operstate to 9938 * 9939 * Transfer operational state from root to device. This is normally 9940 * called when a stacking relationship exists between the root 9941 * device and the device(a leaf device). 9942 */ 9943 void netif_stacked_transfer_operstate(const struct net_device *rootdev, 9944 struct net_device *dev) 9945 { 9946 if (rootdev->operstate == IF_OPER_DORMANT) 9947 netif_dormant_on(dev); 9948 else 9949 netif_dormant_off(dev); 9950 9951 if (rootdev->operstate == IF_OPER_TESTING) 9952 netif_testing_on(dev); 9953 else 9954 netif_testing_off(dev); 9955 9956 if (netif_carrier_ok(rootdev)) 9957 netif_carrier_on(dev); 9958 else 9959 netif_carrier_off(dev); 9960 } 9961 EXPORT_SYMBOL(netif_stacked_transfer_operstate); 9962 9963 static int netif_alloc_rx_queues(struct net_device *dev) 9964 { 9965 unsigned int i, count = dev->num_rx_queues; 9966 struct netdev_rx_queue *rx; 9967 size_t sz = count * sizeof(*rx); 9968 int err = 0; 9969 9970 BUG_ON(count < 1); 9971 9972 rx = kvzalloc(sz, GFP_KERNEL_ACCOUNT | __GFP_RETRY_MAYFAIL); 9973 if (!rx) 9974 return -ENOMEM; 9975 9976 dev->_rx = rx; 9977 9978 for (i = 0; i < count; i++) { 9979 rx[i].dev = dev; 9980 9981 /* XDP RX-queue setup */ 9982 err = xdp_rxq_info_reg(&rx[i].xdp_rxq, dev, i, 0); 9983 if (err < 0) 9984 goto err_rxq_info; 9985 } 9986 return 0; 9987 9988 err_rxq_info: 9989 /* Rollback successful reg's and free other resources */ 9990 while (i--) 9991 xdp_rxq_info_unreg(&rx[i].xdp_rxq); 9992 kvfree(dev->_rx); 9993 dev->_rx = NULL; 9994 return err; 9995 } 9996 9997 static void netif_free_rx_queues(struct net_device *dev) 9998 { 9999 unsigned int i, count = dev->num_rx_queues; 10000 10001 /* netif_alloc_rx_queues alloc failed, resources have been unreg'ed */ 10002 if (!dev->_rx) 10003 return; 10004 10005 for (i = 0; i < count; i++) 10006 xdp_rxq_info_unreg(&dev->_rx[i].xdp_rxq); 10007 10008 kvfree(dev->_rx); 10009 } 10010 10011 static void netdev_init_one_queue(struct net_device *dev, 10012 struct netdev_queue *queue, void *_unused) 10013 { 10014 /* Initialize queue lock */ 10015 spin_lock_init(&queue->_xmit_lock); 10016 netdev_set_xmit_lockdep_class(&queue->_xmit_lock, dev->type); 10017 queue->xmit_lock_owner = -1; 10018 netdev_queue_numa_node_write(queue, NUMA_NO_NODE); 10019 queue->dev = dev; 10020 #ifdef CONFIG_BQL 10021 dql_init(&queue->dql, HZ); 10022 #endif 10023 } 10024 10025 static void netif_free_tx_queues(struct net_device *dev) 10026 { 10027 kvfree(dev->_tx); 10028 } 10029 10030 static int netif_alloc_netdev_queues(struct net_device *dev) 10031 { 10032 unsigned int count = dev->num_tx_queues; 10033 struct netdev_queue *tx; 10034 size_t sz = count * sizeof(*tx); 10035 10036 if (count < 1 || count > 0xffff) 10037 return -EINVAL; 10038 10039 tx = kvzalloc(sz, GFP_KERNEL_ACCOUNT | __GFP_RETRY_MAYFAIL); 10040 if (!tx) 10041 return -ENOMEM; 10042 10043 dev->_tx = tx; 10044 10045 netdev_for_each_tx_queue(dev, netdev_init_one_queue, NULL); 10046 spin_lock_init(&dev->tx_global_lock); 10047 10048 return 0; 10049 } 10050 10051 void netif_tx_stop_all_queues(struct net_device *dev) 10052 { 10053 unsigned int i; 10054 10055 for (i = 0; i < dev->num_tx_queues; i++) { 10056 struct netdev_queue *txq = netdev_get_tx_queue(dev, i); 10057 10058 netif_tx_stop_queue(txq); 10059 } 10060 } 10061 EXPORT_SYMBOL(netif_tx_stop_all_queues); 10062 10063 static int netdev_do_alloc_pcpu_stats(struct net_device *dev) 10064 { 10065 void __percpu *v; 10066 10067 /* Drivers implementing ndo_get_peer_dev must support tstat 10068 * accounting, so that skb_do_redirect() can bump the dev's 10069 * RX stats upon network namespace switch. 10070 */ 10071 if (dev->netdev_ops->ndo_get_peer_dev && 10072 dev->pcpu_stat_type != NETDEV_PCPU_STAT_TSTATS) 10073 return -EOPNOTSUPP; 10074 10075 switch (dev->pcpu_stat_type) { 10076 case NETDEV_PCPU_STAT_NONE: 10077 return 0; 10078 case NETDEV_PCPU_STAT_LSTATS: 10079 v = dev->lstats = netdev_alloc_pcpu_stats(struct pcpu_lstats); 10080 break; 10081 case NETDEV_PCPU_STAT_TSTATS: 10082 v = dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats); 10083 break; 10084 case NETDEV_PCPU_STAT_DSTATS: 10085 v = dev->dstats = netdev_alloc_pcpu_stats(struct pcpu_dstats); 10086 break; 10087 default: 10088 return -EINVAL; 10089 } 10090 10091 return v ? 0 : -ENOMEM; 10092 } 10093 10094 static void netdev_do_free_pcpu_stats(struct net_device *dev) 10095 { 10096 switch (dev->pcpu_stat_type) { 10097 case NETDEV_PCPU_STAT_NONE: 10098 return; 10099 case NETDEV_PCPU_STAT_LSTATS: 10100 free_percpu(dev->lstats); 10101 break; 10102 case NETDEV_PCPU_STAT_TSTATS: 10103 free_percpu(dev->tstats); 10104 break; 10105 case NETDEV_PCPU_STAT_DSTATS: 10106 free_percpu(dev->dstats); 10107 break; 10108 } 10109 } 10110 10111 /** 10112 * register_netdevice() - register a network device 10113 * @dev: device to register 10114 * 10115 * Take a prepared network device structure and make it externally accessible. 10116 * A %NETDEV_REGISTER message is sent to the netdev notifier chain. 10117 * Callers must hold the rtnl lock - you may want register_netdev() 10118 * instead of this. 10119 */ 10120 int register_netdevice(struct net_device *dev) 10121 { 10122 int ret; 10123 struct net *net = dev_net(dev); 10124 10125 BUILD_BUG_ON(sizeof(netdev_features_t) * BITS_PER_BYTE < 10126 NETDEV_FEATURE_COUNT); 10127 BUG_ON(dev_boot_phase); 10128 ASSERT_RTNL(); 10129 10130 might_sleep(); 10131 10132 /* When net_device's are persistent, this will be fatal. */ 10133 BUG_ON(dev->reg_state != NETREG_UNINITIALIZED); 10134 BUG_ON(!net); 10135 10136 ret = ethtool_check_ops(dev->ethtool_ops); 10137 if (ret) 10138 return ret; 10139 10140 spin_lock_init(&dev->addr_list_lock); 10141 netdev_set_addr_lockdep_class(dev); 10142 10143 ret = dev_get_valid_name(net, dev, dev->name); 10144 if (ret < 0) 10145 goto out; 10146 10147 ret = -ENOMEM; 10148 dev->name_node = netdev_name_node_head_alloc(dev); 10149 if (!dev->name_node) 10150 goto out; 10151 10152 /* Init, if this function is available */ 10153 if (dev->netdev_ops->ndo_init) { 10154 ret = dev->netdev_ops->ndo_init(dev); 10155 if (ret) { 10156 if (ret > 0) 10157 ret = -EIO; 10158 goto err_free_name; 10159 } 10160 } 10161 10162 if (((dev->hw_features | dev->features) & 10163 NETIF_F_HW_VLAN_CTAG_FILTER) && 10164 (!dev->netdev_ops->ndo_vlan_rx_add_vid || 10165 !dev->netdev_ops->ndo_vlan_rx_kill_vid)) { 10166 netdev_WARN(dev, "Buggy VLAN acceleration in driver!\n"); 10167 ret = -EINVAL; 10168 goto err_uninit; 10169 } 10170 10171 ret = netdev_do_alloc_pcpu_stats(dev); 10172 if (ret) 10173 goto err_uninit; 10174 10175 ret = dev_index_reserve(net, dev->ifindex); 10176 if (ret < 0) 10177 goto err_free_pcpu; 10178 dev->ifindex = ret; 10179 10180 /* Transfer changeable features to wanted_features and enable 10181 * software offloads (GSO and GRO). 10182 */ 10183 dev->hw_features |= (NETIF_F_SOFT_FEATURES | NETIF_F_SOFT_FEATURES_OFF); 10184 dev->features |= NETIF_F_SOFT_FEATURES; 10185 10186 if (dev->udp_tunnel_nic_info) { 10187 dev->features |= NETIF_F_RX_UDP_TUNNEL_PORT; 10188 dev->hw_features |= NETIF_F_RX_UDP_TUNNEL_PORT; 10189 } 10190 10191 dev->wanted_features = dev->features & dev->hw_features; 10192 10193 if (!(dev->flags & IFF_LOOPBACK)) 10194 dev->hw_features |= NETIF_F_NOCACHE_COPY; 10195 10196 /* If IPv4 TCP segmentation offload is supported we should also 10197 * allow the device to enable segmenting the frame with the option 10198 * of ignoring a static IP ID value. This doesn't enable the 10199 * feature itself but allows the user to enable it later. 10200 */ 10201 if (dev->hw_features & NETIF_F_TSO) 10202 dev->hw_features |= NETIF_F_TSO_MANGLEID; 10203 if (dev->vlan_features & NETIF_F_TSO) 10204 dev->vlan_features |= NETIF_F_TSO_MANGLEID; 10205 if (dev->mpls_features & NETIF_F_TSO) 10206 dev->mpls_features |= NETIF_F_TSO_MANGLEID; 10207 if (dev->hw_enc_features & NETIF_F_TSO) 10208 dev->hw_enc_features |= NETIF_F_TSO_MANGLEID; 10209 10210 /* Make NETIF_F_HIGHDMA inheritable to VLAN devices. 10211 */ 10212 dev->vlan_features |= NETIF_F_HIGHDMA; 10213 10214 /* Make NETIF_F_SG inheritable to tunnel devices. 10215 */ 10216 dev->hw_enc_features |= NETIF_F_SG | NETIF_F_GSO_PARTIAL; 10217 10218 /* Make NETIF_F_SG inheritable to MPLS. 10219 */ 10220 dev->mpls_features |= NETIF_F_SG; 10221 10222 ret = call_netdevice_notifiers(NETDEV_POST_INIT, dev); 10223 ret = notifier_to_errno(ret); 10224 if (ret) 10225 goto err_ifindex_release; 10226 10227 ret = netdev_register_kobject(dev); 10228 write_lock(&dev_base_lock); 10229 dev->reg_state = ret ? NETREG_UNREGISTERED : NETREG_REGISTERED; 10230 write_unlock(&dev_base_lock); 10231 if (ret) 10232 goto err_uninit_notify; 10233 10234 __netdev_update_features(dev); 10235 10236 /* 10237 * Default initial state at registry is that the 10238 * device is present. 10239 */ 10240 10241 set_bit(__LINK_STATE_PRESENT, &dev->state); 10242 10243 linkwatch_init_dev(dev); 10244 10245 dev_init_scheduler(dev); 10246 10247 netdev_hold(dev, &dev->dev_registered_tracker, GFP_KERNEL); 10248 list_netdevice(dev); 10249 10250 add_device_randomness(dev->dev_addr, dev->addr_len); 10251 10252 /* If the device has permanent device address, driver should 10253 * set dev_addr and also addr_assign_type should be set to 10254 * NET_ADDR_PERM (default value). 10255 */ 10256 if (dev->addr_assign_type == NET_ADDR_PERM) 10257 memcpy(dev->perm_addr, dev->dev_addr, dev->addr_len); 10258 10259 /* Notify protocols, that a new device appeared. */ 10260 ret = call_netdevice_notifiers(NETDEV_REGISTER, dev); 10261 ret = notifier_to_errno(ret); 10262 if (ret) { 10263 /* Expect explicit free_netdev() on failure */ 10264 dev->needs_free_netdev = false; 10265 unregister_netdevice_queue(dev, NULL); 10266 goto out; 10267 } 10268 /* 10269 * Prevent userspace races by waiting until the network 10270 * device is fully setup before sending notifications. 10271 */ 10272 if (!dev->rtnl_link_ops || 10273 dev->rtnl_link_state == RTNL_LINK_INITIALIZED) 10274 rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U, GFP_KERNEL, 0, NULL); 10275 10276 out: 10277 return ret; 10278 10279 err_uninit_notify: 10280 call_netdevice_notifiers(NETDEV_PRE_UNINIT, dev); 10281 err_ifindex_release: 10282 dev_index_release(net, dev->ifindex); 10283 err_free_pcpu: 10284 netdev_do_free_pcpu_stats(dev); 10285 err_uninit: 10286 if (dev->netdev_ops->ndo_uninit) 10287 dev->netdev_ops->ndo_uninit(dev); 10288 if (dev->priv_destructor) 10289 dev->priv_destructor(dev); 10290 err_free_name: 10291 netdev_name_node_free(dev->name_node); 10292 goto out; 10293 } 10294 EXPORT_SYMBOL(register_netdevice); 10295 10296 /** 10297 * init_dummy_netdev - init a dummy network device for NAPI 10298 * @dev: device to init 10299 * 10300 * This takes a network device structure and initialize the minimum 10301 * amount of fields so it can be used to schedule NAPI polls without 10302 * registering a full blown interface. This is to be used by drivers 10303 * that need to tie several hardware interfaces to a single NAPI 10304 * poll scheduler due to HW limitations. 10305 */ 10306 int init_dummy_netdev(struct net_device *dev) 10307 { 10308 /* Clear everything. Note we don't initialize spinlocks 10309 * are they aren't supposed to be taken by any of the 10310 * NAPI code and this dummy netdev is supposed to be 10311 * only ever used for NAPI polls 10312 */ 10313 memset(dev, 0, sizeof(struct net_device)); 10314 10315 /* make sure we BUG if trying to hit standard 10316 * register/unregister code path 10317 */ 10318 dev->reg_state = NETREG_DUMMY; 10319 10320 /* NAPI wants this */ 10321 INIT_LIST_HEAD(&dev->napi_list); 10322 10323 /* a dummy interface is started by default */ 10324 set_bit(__LINK_STATE_PRESENT, &dev->state); 10325 set_bit(__LINK_STATE_START, &dev->state); 10326 10327 /* napi_busy_loop stats accounting wants this */ 10328 dev_net_set(dev, &init_net); 10329 10330 /* Note : We dont allocate pcpu_refcnt for dummy devices, 10331 * because users of this 'device' dont need to change 10332 * its refcount. 10333 */ 10334 10335 return 0; 10336 } 10337 EXPORT_SYMBOL_GPL(init_dummy_netdev); 10338 10339 10340 /** 10341 * register_netdev - register a network device 10342 * @dev: device to register 10343 * 10344 * Take a completed network device structure and add it to the kernel 10345 * interfaces. A %NETDEV_REGISTER message is sent to the netdev notifier 10346 * chain. 0 is returned on success. A negative errno code is returned 10347 * on a failure to set up the device, or if the name is a duplicate. 10348 * 10349 * This is a wrapper around register_netdevice that takes the rtnl semaphore 10350 * and expands the device name if you passed a format string to 10351 * alloc_netdev. 10352 */ 10353 int register_netdev(struct net_device *dev) 10354 { 10355 int err; 10356 10357 if (rtnl_lock_killable()) 10358 return -EINTR; 10359 err = register_netdevice(dev); 10360 rtnl_unlock(); 10361 return err; 10362 } 10363 EXPORT_SYMBOL(register_netdev); 10364 10365 int netdev_refcnt_read(const struct net_device *dev) 10366 { 10367 #ifdef CONFIG_PCPU_DEV_REFCNT 10368 int i, refcnt = 0; 10369 10370 for_each_possible_cpu(i) 10371 refcnt += *per_cpu_ptr(dev->pcpu_refcnt, i); 10372 return refcnt; 10373 #else 10374 return refcount_read(&dev->dev_refcnt); 10375 #endif 10376 } 10377 EXPORT_SYMBOL(netdev_refcnt_read); 10378 10379 int netdev_unregister_timeout_secs __read_mostly = 10; 10380 10381 #define WAIT_REFS_MIN_MSECS 1 10382 #define WAIT_REFS_MAX_MSECS 250 10383 /** 10384 * netdev_wait_allrefs_any - wait until all references are gone. 10385 * @list: list of net_devices to wait on 10386 * 10387 * This is called when unregistering network devices. 10388 * 10389 * Any protocol or device that holds a reference should register 10390 * for netdevice notification, and cleanup and put back the 10391 * reference if they receive an UNREGISTER event. 10392 * We can get stuck here if buggy protocols don't correctly 10393 * call dev_put. 10394 */ 10395 static struct net_device *netdev_wait_allrefs_any(struct list_head *list) 10396 { 10397 unsigned long rebroadcast_time, warning_time; 10398 struct net_device *dev; 10399 int wait = 0; 10400 10401 rebroadcast_time = warning_time = jiffies; 10402 10403 list_for_each_entry(dev, list, todo_list) 10404 if (netdev_refcnt_read(dev) == 1) 10405 return dev; 10406 10407 while (true) { 10408 if (time_after(jiffies, rebroadcast_time + 1 * HZ)) { 10409 rtnl_lock(); 10410 10411 /* Rebroadcast unregister notification */ 10412 list_for_each_entry(dev, list, todo_list) 10413 call_netdevice_notifiers(NETDEV_UNREGISTER, dev); 10414 10415 __rtnl_unlock(); 10416 rcu_barrier(); 10417 rtnl_lock(); 10418 10419 list_for_each_entry(dev, list, todo_list) 10420 if (test_bit(__LINK_STATE_LINKWATCH_PENDING, 10421 &dev->state)) { 10422 /* We must not have linkwatch events 10423 * pending on unregister. If this 10424 * happens, we simply run the queue 10425 * unscheduled, resulting in a noop 10426 * for this device. 10427 */ 10428 linkwatch_run_queue(); 10429 break; 10430 } 10431 10432 __rtnl_unlock(); 10433 10434 rebroadcast_time = jiffies; 10435 } 10436 10437 rcu_barrier(); 10438 10439 if (!wait) { 10440 wait = WAIT_REFS_MIN_MSECS; 10441 } else { 10442 msleep(wait); 10443 wait = min(wait << 1, WAIT_REFS_MAX_MSECS); 10444 } 10445 10446 list_for_each_entry(dev, list, todo_list) 10447 if (netdev_refcnt_read(dev) == 1) 10448 return dev; 10449 10450 if (time_after(jiffies, warning_time + 10451 READ_ONCE(netdev_unregister_timeout_secs) * HZ)) { 10452 list_for_each_entry(dev, list, todo_list) { 10453 pr_emerg("unregister_netdevice: waiting for %s to become free. Usage count = %d\n", 10454 dev->name, netdev_refcnt_read(dev)); 10455 ref_tracker_dir_print(&dev->refcnt_tracker, 10); 10456 } 10457 10458 warning_time = jiffies; 10459 } 10460 } 10461 } 10462 10463 /* The sequence is: 10464 * 10465 * rtnl_lock(); 10466 * ... 10467 * register_netdevice(x1); 10468 * register_netdevice(x2); 10469 * ... 10470 * unregister_netdevice(y1); 10471 * unregister_netdevice(y2); 10472 * ... 10473 * rtnl_unlock(); 10474 * free_netdev(y1); 10475 * free_netdev(y2); 10476 * 10477 * We are invoked by rtnl_unlock(). 10478 * This allows us to deal with problems: 10479 * 1) We can delete sysfs objects which invoke hotplug 10480 * without deadlocking with linkwatch via keventd. 10481 * 2) Since we run with the RTNL semaphore not held, we can sleep 10482 * safely in order to wait for the netdev refcnt to drop to zero. 10483 * 10484 * We must not return until all unregister events added during 10485 * the interval the lock was held have been completed. 10486 */ 10487 void netdev_run_todo(void) 10488 { 10489 struct net_device *dev, *tmp; 10490 struct list_head list; 10491 #ifdef CONFIG_LOCKDEP 10492 struct list_head unlink_list; 10493 10494 list_replace_init(&net_unlink_list, &unlink_list); 10495 10496 while (!list_empty(&unlink_list)) { 10497 struct net_device *dev = list_first_entry(&unlink_list, 10498 struct net_device, 10499 unlink_list); 10500 list_del_init(&dev->unlink_list); 10501 dev->nested_level = dev->lower_level - 1; 10502 } 10503 #endif 10504 10505 /* Snapshot list, allow later requests */ 10506 list_replace_init(&net_todo_list, &list); 10507 10508 __rtnl_unlock(); 10509 10510 /* Wait for rcu callbacks to finish before next phase */ 10511 if (!list_empty(&list)) 10512 rcu_barrier(); 10513 10514 list_for_each_entry_safe(dev, tmp, &list, todo_list) { 10515 if (unlikely(dev->reg_state != NETREG_UNREGISTERING)) { 10516 netdev_WARN(dev, "run_todo but not unregistering\n"); 10517 list_del(&dev->todo_list); 10518 continue; 10519 } 10520 10521 write_lock(&dev_base_lock); 10522 dev->reg_state = NETREG_UNREGISTERED; 10523 write_unlock(&dev_base_lock); 10524 linkwatch_forget_dev(dev); 10525 } 10526 10527 while (!list_empty(&list)) { 10528 dev = netdev_wait_allrefs_any(&list); 10529 list_del(&dev->todo_list); 10530 10531 /* paranoia */ 10532 BUG_ON(netdev_refcnt_read(dev) != 1); 10533 BUG_ON(!list_empty(&dev->ptype_all)); 10534 BUG_ON(!list_empty(&dev->ptype_specific)); 10535 WARN_ON(rcu_access_pointer(dev->ip_ptr)); 10536 WARN_ON(rcu_access_pointer(dev->ip6_ptr)); 10537 10538 netdev_do_free_pcpu_stats(dev); 10539 if (dev->priv_destructor) 10540 dev->priv_destructor(dev); 10541 if (dev->needs_free_netdev) 10542 free_netdev(dev); 10543 10544 if (atomic_dec_and_test(&dev_net(dev)->dev_unreg_count)) 10545 wake_up(&netdev_unregistering_wq); 10546 10547 /* Free network device */ 10548 kobject_put(&dev->dev.kobj); 10549 } 10550 } 10551 10552 /* Convert net_device_stats to rtnl_link_stats64. rtnl_link_stats64 has 10553 * all the same fields in the same order as net_device_stats, with only 10554 * the type differing, but rtnl_link_stats64 may have additional fields 10555 * at the end for newer counters. 10556 */ 10557 void netdev_stats_to_stats64(struct rtnl_link_stats64 *stats64, 10558 const struct net_device_stats *netdev_stats) 10559 { 10560 size_t i, n = sizeof(*netdev_stats) / sizeof(atomic_long_t); 10561 const atomic_long_t *src = (atomic_long_t *)netdev_stats; 10562 u64 *dst = (u64 *)stats64; 10563 10564 BUILD_BUG_ON(n > sizeof(*stats64) / sizeof(u64)); 10565 for (i = 0; i < n; i++) 10566 dst[i] = (unsigned long)atomic_long_read(&src[i]); 10567 /* zero out counters that only exist in rtnl_link_stats64 */ 10568 memset((char *)stats64 + n * sizeof(u64), 0, 10569 sizeof(*stats64) - n * sizeof(u64)); 10570 } 10571 EXPORT_SYMBOL(netdev_stats_to_stats64); 10572 10573 struct net_device_core_stats __percpu *netdev_core_stats_alloc(struct net_device *dev) 10574 { 10575 struct net_device_core_stats __percpu *p; 10576 10577 p = alloc_percpu_gfp(struct net_device_core_stats, 10578 GFP_ATOMIC | __GFP_NOWARN); 10579 10580 if (p && cmpxchg(&dev->core_stats, NULL, p)) 10581 free_percpu(p); 10582 10583 /* This READ_ONCE() pairs with the cmpxchg() above */ 10584 return READ_ONCE(dev->core_stats); 10585 } 10586 EXPORT_SYMBOL(netdev_core_stats_alloc); 10587 10588 /** 10589 * dev_get_stats - get network device statistics 10590 * @dev: device to get statistics from 10591 * @storage: place to store stats 10592 * 10593 * Get network statistics from device. Return @storage. 10594 * The device driver may provide its own method by setting 10595 * dev->netdev_ops->get_stats64 or dev->netdev_ops->get_stats; 10596 * otherwise the internal statistics structure is used. 10597 */ 10598 struct rtnl_link_stats64 *dev_get_stats(struct net_device *dev, 10599 struct rtnl_link_stats64 *storage) 10600 { 10601 const struct net_device_ops *ops = dev->netdev_ops; 10602 const struct net_device_core_stats __percpu *p; 10603 10604 if (ops->ndo_get_stats64) { 10605 memset(storage, 0, sizeof(*storage)); 10606 ops->ndo_get_stats64(dev, storage); 10607 } else if (ops->ndo_get_stats) { 10608 netdev_stats_to_stats64(storage, ops->ndo_get_stats(dev)); 10609 } else { 10610 netdev_stats_to_stats64(storage, &dev->stats); 10611 } 10612 10613 /* This READ_ONCE() pairs with the write in netdev_core_stats_alloc() */ 10614 p = READ_ONCE(dev->core_stats); 10615 if (p) { 10616 const struct net_device_core_stats *core_stats; 10617 int i; 10618 10619 for_each_possible_cpu(i) { 10620 core_stats = per_cpu_ptr(p, i); 10621 storage->rx_dropped += READ_ONCE(core_stats->rx_dropped); 10622 storage->tx_dropped += READ_ONCE(core_stats->tx_dropped); 10623 storage->rx_nohandler += READ_ONCE(core_stats->rx_nohandler); 10624 storage->rx_otherhost_dropped += READ_ONCE(core_stats->rx_otherhost_dropped); 10625 } 10626 } 10627 return storage; 10628 } 10629 EXPORT_SYMBOL(dev_get_stats); 10630 10631 /** 10632 * dev_fetch_sw_netstats - get per-cpu network device statistics 10633 * @s: place to store stats 10634 * @netstats: per-cpu network stats to read from 10635 * 10636 * Read per-cpu network statistics and populate the related fields in @s. 10637 */ 10638 void dev_fetch_sw_netstats(struct rtnl_link_stats64 *s, 10639 const struct pcpu_sw_netstats __percpu *netstats) 10640 { 10641 int cpu; 10642 10643 for_each_possible_cpu(cpu) { 10644 u64 rx_packets, rx_bytes, tx_packets, tx_bytes; 10645 const struct pcpu_sw_netstats *stats; 10646 unsigned int start; 10647 10648 stats = per_cpu_ptr(netstats, cpu); 10649 do { 10650 start = u64_stats_fetch_begin(&stats->syncp); 10651 rx_packets = u64_stats_read(&stats->rx_packets); 10652 rx_bytes = u64_stats_read(&stats->rx_bytes); 10653 tx_packets = u64_stats_read(&stats->tx_packets); 10654 tx_bytes = u64_stats_read(&stats->tx_bytes); 10655 } while (u64_stats_fetch_retry(&stats->syncp, start)); 10656 10657 s->rx_packets += rx_packets; 10658 s->rx_bytes += rx_bytes; 10659 s->tx_packets += tx_packets; 10660 s->tx_bytes += tx_bytes; 10661 } 10662 } 10663 EXPORT_SYMBOL_GPL(dev_fetch_sw_netstats); 10664 10665 /** 10666 * dev_get_tstats64 - ndo_get_stats64 implementation 10667 * @dev: device to get statistics from 10668 * @s: place to store stats 10669 * 10670 * Populate @s from dev->stats and dev->tstats. Can be used as 10671 * ndo_get_stats64() callback. 10672 */ 10673 void dev_get_tstats64(struct net_device *dev, struct rtnl_link_stats64 *s) 10674 { 10675 netdev_stats_to_stats64(s, &dev->stats); 10676 dev_fetch_sw_netstats(s, dev->tstats); 10677 } 10678 EXPORT_SYMBOL_GPL(dev_get_tstats64); 10679 10680 struct netdev_queue *dev_ingress_queue_create(struct net_device *dev) 10681 { 10682 struct netdev_queue *queue = dev_ingress_queue(dev); 10683 10684 #ifdef CONFIG_NET_CLS_ACT 10685 if (queue) 10686 return queue; 10687 queue = kzalloc(sizeof(*queue), GFP_KERNEL); 10688 if (!queue) 10689 return NULL; 10690 netdev_init_one_queue(dev, queue, NULL); 10691 RCU_INIT_POINTER(queue->qdisc, &noop_qdisc); 10692 RCU_INIT_POINTER(queue->qdisc_sleeping, &noop_qdisc); 10693 rcu_assign_pointer(dev->ingress_queue, queue); 10694 #endif 10695 return queue; 10696 } 10697 10698 static const struct ethtool_ops default_ethtool_ops; 10699 10700 void netdev_set_default_ethtool_ops(struct net_device *dev, 10701 const struct ethtool_ops *ops) 10702 { 10703 if (dev->ethtool_ops == &default_ethtool_ops) 10704 dev->ethtool_ops = ops; 10705 } 10706 EXPORT_SYMBOL_GPL(netdev_set_default_ethtool_ops); 10707 10708 /** 10709 * netdev_sw_irq_coalesce_default_on() - enable SW IRQ coalescing by default 10710 * @dev: netdev to enable the IRQ coalescing on 10711 * 10712 * Sets a conservative default for SW IRQ coalescing. Users can use 10713 * sysfs attributes to override the default values. 10714 */ 10715 void netdev_sw_irq_coalesce_default_on(struct net_device *dev) 10716 { 10717 WARN_ON(dev->reg_state == NETREG_REGISTERED); 10718 10719 if (!IS_ENABLED(CONFIG_PREEMPT_RT)) { 10720 dev->gro_flush_timeout = 20000; 10721 dev->napi_defer_hard_irqs = 1; 10722 } 10723 } 10724 EXPORT_SYMBOL_GPL(netdev_sw_irq_coalesce_default_on); 10725 10726 void netdev_freemem(struct net_device *dev) 10727 { 10728 char *addr = (char *)dev - dev->padded; 10729 10730 kvfree(addr); 10731 } 10732 10733 /** 10734 * alloc_netdev_mqs - allocate network device 10735 * @sizeof_priv: size of private data to allocate space for 10736 * @name: device name format string 10737 * @name_assign_type: origin of device name 10738 * @setup: callback to initialize device 10739 * @txqs: the number of TX subqueues to allocate 10740 * @rxqs: the number of RX subqueues to allocate 10741 * 10742 * Allocates a struct net_device with private data area for driver use 10743 * and performs basic initialization. Also allocates subqueue structs 10744 * for each queue on the device. 10745 */ 10746 struct net_device *alloc_netdev_mqs(int sizeof_priv, const char *name, 10747 unsigned char name_assign_type, 10748 void (*setup)(struct net_device *), 10749 unsigned int txqs, unsigned int rxqs) 10750 { 10751 struct net_device *dev; 10752 unsigned int alloc_size; 10753 struct net_device *p; 10754 10755 BUG_ON(strlen(name) >= sizeof(dev->name)); 10756 10757 if (txqs < 1) { 10758 pr_err("alloc_netdev: Unable to allocate device with zero queues\n"); 10759 return NULL; 10760 } 10761 10762 if (rxqs < 1) { 10763 pr_err("alloc_netdev: Unable to allocate device with zero RX queues\n"); 10764 return NULL; 10765 } 10766 10767 alloc_size = sizeof(struct net_device); 10768 if (sizeof_priv) { 10769 /* ensure 32-byte alignment of private area */ 10770 alloc_size = ALIGN(alloc_size, NETDEV_ALIGN); 10771 alloc_size += sizeof_priv; 10772 } 10773 /* ensure 32-byte alignment of whole construct */ 10774 alloc_size += NETDEV_ALIGN - 1; 10775 10776 p = kvzalloc(alloc_size, GFP_KERNEL_ACCOUNT | __GFP_RETRY_MAYFAIL); 10777 if (!p) 10778 return NULL; 10779 10780 dev = PTR_ALIGN(p, NETDEV_ALIGN); 10781 dev->padded = (char *)dev - (char *)p; 10782 10783 ref_tracker_dir_init(&dev->refcnt_tracker, 128, name); 10784 #ifdef CONFIG_PCPU_DEV_REFCNT 10785 dev->pcpu_refcnt = alloc_percpu(int); 10786 if (!dev->pcpu_refcnt) 10787 goto free_dev; 10788 __dev_hold(dev); 10789 #else 10790 refcount_set(&dev->dev_refcnt, 1); 10791 #endif 10792 10793 if (dev_addr_init(dev)) 10794 goto free_pcpu; 10795 10796 dev_mc_init(dev); 10797 dev_uc_init(dev); 10798 10799 dev_net_set(dev, &init_net); 10800 10801 dev->gso_max_size = GSO_LEGACY_MAX_SIZE; 10802 dev->xdp_zc_max_segs = 1; 10803 dev->gso_max_segs = GSO_MAX_SEGS; 10804 dev->gro_max_size = GRO_LEGACY_MAX_SIZE; 10805 dev->gso_ipv4_max_size = GSO_LEGACY_MAX_SIZE; 10806 dev->gro_ipv4_max_size = GRO_LEGACY_MAX_SIZE; 10807 dev->tso_max_size = TSO_LEGACY_MAX_SIZE; 10808 dev->tso_max_segs = TSO_MAX_SEGS; 10809 dev->upper_level = 1; 10810 dev->lower_level = 1; 10811 #ifdef CONFIG_LOCKDEP 10812 dev->nested_level = 0; 10813 INIT_LIST_HEAD(&dev->unlink_list); 10814 #endif 10815 10816 INIT_LIST_HEAD(&dev->napi_list); 10817 INIT_LIST_HEAD(&dev->unreg_list); 10818 INIT_LIST_HEAD(&dev->close_list); 10819 INIT_LIST_HEAD(&dev->link_watch_list); 10820 INIT_LIST_HEAD(&dev->adj_list.upper); 10821 INIT_LIST_HEAD(&dev->adj_list.lower); 10822 INIT_LIST_HEAD(&dev->ptype_all); 10823 INIT_LIST_HEAD(&dev->ptype_specific); 10824 INIT_LIST_HEAD(&dev->net_notifier_list); 10825 #ifdef CONFIG_NET_SCHED 10826 hash_init(dev->qdisc_hash); 10827 #endif 10828 dev->priv_flags = IFF_XMIT_DST_RELEASE | IFF_XMIT_DST_RELEASE_PERM; 10829 setup(dev); 10830 10831 if (!dev->tx_queue_len) { 10832 dev->priv_flags |= IFF_NO_QUEUE; 10833 dev->tx_queue_len = DEFAULT_TX_QUEUE_LEN; 10834 } 10835 10836 dev->num_tx_queues = txqs; 10837 dev->real_num_tx_queues = txqs; 10838 if (netif_alloc_netdev_queues(dev)) 10839 goto free_all; 10840 10841 dev->num_rx_queues = rxqs; 10842 dev->real_num_rx_queues = rxqs; 10843 if (netif_alloc_rx_queues(dev)) 10844 goto free_all; 10845 10846 strcpy(dev->name, name); 10847 dev->name_assign_type = name_assign_type; 10848 dev->group = INIT_NETDEV_GROUP; 10849 if (!dev->ethtool_ops) 10850 dev->ethtool_ops = &default_ethtool_ops; 10851 10852 nf_hook_netdev_init(dev); 10853 10854 return dev; 10855 10856 free_all: 10857 free_netdev(dev); 10858 return NULL; 10859 10860 free_pcpu: 10861 #ifdef CONFIG_PCPU_DEV_REFCNT 10862 free_percpu(dev->pcpu_refcnt); 10863 free_dev: 10864 #endif 10865 netdev_freemem(dev); 10866 return NULL; 10867 } 10868 EXPORT_SYMBOL(alloc_netdev_mqs); 10869 10870 /** 10871 * free_netdev - free network device 10872 * @dev: device 10873 * 10874 * This function does the last stage of destroying an allocated device 10875 * interface. The reference to the device object is released. If this 10876 * is the last reference then it will be freed.Must be called in process 10877 * context. 10878 */ 10879 void free_netdev(struct net_device *dev) 10880 { 10881 struct napi_struct *p, *n; 10882 10883 might_sleep(); 10884 10885 /* When called immediately after register_netdevice() failed the unwind 10886 * handling may still be dismantling the device. Handle that case by 10887 * deferring the free. 10888 */ 10889 if (dev->reg_state == NETREG_UNREGISTERING) { 10890 ASSERT_RTNL(); 10891 dev->needs_free_netdev = true; 10892 return; 10893 } 10894 10895 netif_free_tx_queues(dev); 10896 netif_free_rx_queues(dev); 10897 10898 kfree(rcu_dereference_protected(dev->ingress_queue, 1)); 10899 10900 /* Flush device addresses */ 10901 dev_addr_flush(dev); 10902 10903 list_for_each_entry_safe(p, n, &dev->napi_list, dev_list) 10904 netif_napi_del(p); 10905 10906 ref_tracker_dir_exit(&dev->refcnt_tracker); 10907 #ifdef CONFIG_PCPU_DEV_REFCNT 10908 free_percpu(dev->pcpu_refcnt); 10909 dev->pcpu_refcnt = NULL; 10910 #endif 10911 free_percpu(dev->core_stats); 10912 dev->core_stats = NULL; 10913 free_percpu(dev->xdp_bulkq); 10914 dev->xdp_bulkq = NULL; 10915 10916 /* Compatibility with error handling in drivers */ 10917 if (dev->reg_state == NETREG_UNINITIALIZED) { 10918 netdev_freemem(dev); 10919 return; 10920 } 10921 10922 BUG_ON(dev->reg_state != NETREG_UNREGISTERED); 10923 dev->reg_state = NETREG_RELEASED; 10924 10925 /* will free via device release */ 10926 put_device(&dev->dev); 10927 } 10928 EXPORT_SYMBOL(free_netdev); 10929 10930 /** 10931 * synchronize_net - Synchronize with packet receive processing 10932 * 10933 * Wait for packets currently being received to be done. 10934 * Does not block later packets from starting. 10935 */ 10936 void synchronize_net(void) 10937 { 10938 might_sleep(); 10939 if (rtnl_is_locked()) 10940 synchronize_rcu_expedited(); 10941 else 10942 synchronize_rcu(); 10943 } 10944 EXPORT_SYMBOL(synchronize_net); 10945 10946 /** 10947 * unregister_netdevice_queue - remove device from the kernel 10948 * @dev: device 10949 * @head: list 10950 * 10951 * This function shuts down a device interface and removes it 10952 * from the kernel tables. 10953 * If head not NULL, device is queued to be unregistered later. 10954 * 10955 * Callers must hold the rtnl semaphore. You may want 10956 * unregister_netdev() instead of this. 10957 */ 10958 10959 void unregister_netdevice_queue(struct net_device *dev, struct list_head *head) 10960 { 10961 ASSERT_RTNL(); 10962 10963 if (head) { 10964 list_move_tail(&dev->unreg_list, head); 10965 } else { 10966 LIST_HEAD(single); 10967 10968 list_add(&dev->unreg_list, &single); 10969 unregister_netdevice_many(&single); 10970 } 10971 } 10972 EXPORT_SYMBOL(unregister_netdevice_queue); 10973 10974 void unregister_netdevice_many_notify(struct list_head *head, 10975 u32 portid, const struct nlmsghdr *nlh) 10976 { 10977 struct net_device *dev, *tmp; 10978 LIST_HEAD(close_head); 10979 10980 BUG_ON(dev_boot_phase); 10981 ASSERT_RTNL(); 10982 10983 if (list_empty(head)) 10984 return; 10985 10986 list_for_each_entry_safe(dev, tmp, head, unreg_list) { 10987 /* Some devices call without registering 10988 * for initialization unwind. Remove those 10989 * devices and proceed with the remaining. 10990 */ 10991 if (dev->reg_state == NETREG_UNINITIALIZED) { 10992 pr_debug("unregister_netdevice: device %s/%p never was registered\n", 10993 dev->name, dev); 10994 10995 WARN_ON(1); 10996 list_del(&dev->unreg_list); 10997 continue; 10998 } 10999 dev->dismantle = true; 11000 BUG_ON(dev->reg_state != NETREG_REGISTERED); 11001 } 11002 11003 /* If device is running, close it first. */ 11004 list_for_each_entry(dev, head, unreg_list) 11005 list_add_tail(&dev->close_list, &close_head); 11006 dev_close_many(&close_head, true); 11007 11008 list_for_each_entry(dev, head, unreg_list) { 11009 /* And unlink it from device chain. */ 11010 write_lock(&dev_base_lock); 11011 unlist_netdevice(dev, false); 11012 dev->reg_state = NETREG_UNREGISTERING; 11013 write_unlock(&dev_base_lock); 11014 } 11015 flush_all_backlogs(); 11016 11017 synchronize_net(); 11018 11019 list_for_each_entry(dev, head, unreg_list) { 11020 struct sk_buff *skb = NULL; 11021 11022 /* Shutdown queueing discipline. */ 11023 dev_shutdown(dev); 11024 dev_tcx_uninstall(dev); 11025 dev_xdp_uninstall(dev); 11026 bpf_dev_bound_netdev_unregister(dev); 11027 11028 netdev_offload_xstats_disable_all(dev); 11029 11030 /* Notify protocols, that we are about to destroy 11031 * this device. They should clean all the things. 11032 */ 11033 call_netdevice_notifiers(NETDEV_UNREGISTER, dev); 11034 11035 if (!dev->rtnl_link_ops || 11036 dev->rtnl_link_state == RTNL_LINK_INITIALIZED) 11037 skb = rtmsg_ifinfo_build_skb(RTM_DELLINK, dev, ~0U, 0, 11038 GFP_KERNEL, NULL, 0, 11039 portid, nlh); 11040 11041 /* 11042 * Flush the unicast and multicast chains 11043 */ 11044 dev_uc_flush(dev); 11045 dev_mc_flush(dev); 11046 11047 netdev_name_node_alt_flush(dev); 11048 netdev_name_node_free(dev->name_node); 11049 11050 call_netdevice_notifiers(NETDEV_PRE_UNINIT, dev); 11051 11052 if (dev->netdev_ops->ndo_uninit) 11053 dev->netdev_ops->ndo_uninit(dev); 11054 11055 if (skb) 11056 rtmsg_ifinfo_send(skb, dev, GFP_KERNEL, portid, nlh); 11057 11058 /* Notifier chain MUST detach us all upper devices. */ 11059 WARN_ON(netdev_has_any_upper_dev(dev)); 11060 WARN_ON(netdev_has_any_lower_dev(dev)); 11061 11062 /* Remove entries from kobject tree */ 11063 netdev_unregister_kobject(dev); 11064 #ifdef CONFIG_XPS 11065 /* Remove XPS queueing entries */ 11066 netif_reset_xps_queues_gt(dev, 0); 11067 #endif 11068 } 11069 11070 synchronize_net(); 11071 11072 list_for_each_entry(dev, head, unreg_list) { 11073 netdev_put(dev, &dev->dev_registered_tracker); 11074 net_set_todo(dev); 11075 } 11076 11077 list_del(head); 11078 } 11079 11080 /** 11081 * unregister_netdevice_many - unregister many devices 11082 * @head: list of devices 11083 * 11084 * Note: As most callers use a stack allocated list_head, 11085 * we force a list_del() to make sure stack wont be corrupted later. 11086 */ 11087 void unregister_netdevice_many(struct list_head *head) 11088 { 11089 unregister_netdevice_many_notify(head, 0, NULL); 11090 } 11091 EXPORT_SYMBOL(unregister_netdevice_many); 11092 11093 /** 11094 * unregister_netdev - remove device from the kernel 11095 * @dev: device 11096 * 11097 * This function shuts down a device interface and removes it 11098 * from the kernel tables. 11099 * 11100 * This is just a wrapper for unregister_netdevice that takes 11101 * the rtnl semaphore. In general you want to use this and not 11102 * unregister_netdevice. 11103 */ 11104 void unregister_netdev(struct net_device *dev) 11105 { 11106 rtnl_lock(); 11107 unregister_netdevice(dev); 11108 rtnl_unlock(); 11109 } 11110 EXPORT_SYMBOL(unregister_netdev); 11111 11112 /** 11113 * __dev_change_net_namespace - move device to different nethost namespace 11114 * @dev: device 11115 * @net: network namespace 11116 * @pat: If not NULL name pattern to try if the current device name 11117 * is already taken in the destination network namespace. 11118 * @new_ifindex: If not zero, specifies device index in the target 11119 * namespace. 11120 * 11121 * This function shuts down a device interface and moves it 11122 * to a new network namespace. On success 0 is returned, on 11123 * a failure a netagive errno code is returned. 11124 * 11125 * Callers must hold the rtnl semaphore. 11126 */ 11127 11128 int __dev_change_net_namespace(struct net_device *dev, struct net *net, 11129 const char *pat, int new_ifindex) 11130 { 11131 struct netdev_name_node *name_node; 11132 struct net *net_old = dev_net(dev); 11133 char new_name[IFNAMSIZ] = {}; 11134 int err, new_nsid; 11135 11136 ASSERT_RTNL(); 11137 11138 /* Don't allow namespace local devices to be moved. */ 11139 err = -EINVAL; 11140 if (dev->features & NETIF_F_NETNS_LOCAL) 11141 goto out; 11142 11143 /* Ensure the device has been registrered */ 11144 if (dev->reg_state != NETREG_REGISTERED) 11145 goto out; 11146 11147 /* Get out if there is nothing todo */ 11148 err = 0; 11149 if (net_eq(net_old, net)) 11150 goto out; 11151 11152 /* Pick the destination device name, and ensure 11153 * we can use it in the destination network namespace. 11154 */ 11155 err = -EEXIST; 11156 if (netdev_name_in_use(net, dev->name)) { 11157 /* We get here if we can't use the current device name */ 11158 if (!pat) 11159 goto out; 11160 err = dev_prep_valid_name(net, dev, pat, new_name); 11161 if (err < 0) 11162 goto out; 11163 } 11164 /* Check that none of the altnames conflicts. */ 11165 err = -EEXIST; 11166 netdev_for_each_altname(dev, name_node) 11167 if (netdev_name_in_use(net, name_node->name)) 11168 goto out; 11169 11170 /* Check that new_ifindex isn't used yet. */ 11171 if (new_ifindex) { 11172 err = dev_index_reserve(net, new_ifindex); 11173 if (err < 0) 11174 goto out; 11175 } else { 11176 /* If there is an ifindex conflict assign a new one */ 11177 err = dev_index_reserve(net, dev->ifindex); 11178 if (err == -EBUSY) 11179 err = dev_index_reserve(net, 0); 11180 if (err < 0) 11181 goto out; 11182 new_ifindex = err; 11183 } 11184 11185 /* 11186 * And now a mini version of register_netdevice unregister_netdevice. 11187 */ 11188 11189 /* If device is running close it first. */ 11190 dev_close(dev); 11191 11192 /* And unlink it from device chain */ 11193 unlist_netdevice(dev, true); 11194 11195 synchronize_net(); 11196 11197 /* Shutdown queueing discipline. */ 11198 dev_shutdown(dev); 11199 11200 /* Notify protocols, that we are about to destroy 11201 * this device. They should clean all the things. 11202 * 11203 * Note that dev->reg_state stays at NETREG_REGISTERED. 11204 * This is wanted because this way 8021q and macvlan know 11205 * the device is just moving and can keep their slaves up. 11206 */ 11207 call_netdevice_notifiers(NETDEV_UNREGISTER, dev); 11208 rcu_barrier(); 11209 11210 new_nsid = peernet2id_alloc(dev_net(dev), net, GFP_KERNEL); 11211 11212 rtmsg_ifinfo_newnet(RTM_DELLINK, dev, ~0U, GFP_KERNEL, &new_nsid, 11213 new_ifindex); 11214 11215 /* 11216 * Flush the unicast and multicast chains 11217 */ 11218 dev_uc_flush(dev); 11219 dev_mc_flush(dev); 11220 11221 /* Send a netdev-removed uevent to the old namespace */ 11222 kobject_uevent(&dev->dev.kobj, KOBJ_REMOVE); 11223 netdev_adjacent_del_links(dev); 11224 11225 /* Move per-net netdevice notifiers that are following the netdevice */ 11226 move_netdevice_notifiers_dev_net(dev, net); 11227 11228 /* Actually switch the network namespace */ 11229 dev_net_set(dev, net); 11230 dev->ifindex = new_ifindex; 11231 11232 /* Send a netdev-add uevent to the new namespace */ 11233 kobject_uevent(&dev->dev.kobj, KOBJ_ADD); 11234 netdev_adjacent_add_links(dev); 11235 11236 if (new_name[0]) /* Rename the netdev to prepared name */ 11237 strscpy(dev->name, new_name, IFNAMSIZ); 11238 11239 /* Fixup kobjects */ 11240 err = device_rename(&dev->dev, dev->name); 11241 WARN_ON(err); 11242 11243 /* Adapt owner in case owning user namespace of target network 11244 * namespace is different from the original one. 11245 */ 11246 err = netdev_change_owner(dev, net_old, net); 11247 WARN_ON(err); 11248 11249 /* Add the device back in the hashes */ 11250 list_netdevice(dev); 11251 11252 /* Notify protocols, that a new device appeared. */ 11253 call_netdevice_notifiers(NETDEV_REGISTER, dev); 11254 11255 /* 11256 * Prevent userspace races by waiting until the network 11257 * device is fully setup before sending notifications. 11258 */ 11259 rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U, GFP_KERNEL, 0, NULL); 11260 11261 synchronize_net(); 11262 err = 0; 11263 out: 11264 return err; 11265 } 11266 EXPORT_SYMBOL_GPL(__dev_change_net_namespace); 11267 11268 static int dev_cpu_dead(unsigned int oldcpu) 11269 { 11270 struct sk_buff **list_skb; 11271 struct sk_buff *skb; 11272 unsigned int cpu; 11273 struct softnet_data *sd, *oldsd, *remsd = NULL; 11274 11275 local_irq_disable(); 11276 cpu = smp_processor_id(); 11277 sd = &per_cpu(softnet_data, cpu); 11278 oldsd = &per_cpu(softnet_data, oldcpu); 11279 11280 /* Find end of our completion_queue. */ 11281 list_skb = &sd->completion_queue; 11282 while (*list_skb) 11283 list_skb = &(*list_skb)->next; 11284 /* Append completion queue from offline CPU. */ 11285 *list_skb = oldsd->completion_queue; 11286 oldsd->completion_queue = NULL; 11287 11288 /* Append output queue from offline CPU. */ 11289 if (oldsd->output_queue) { 11290 *sd->output_queue_tailp = oldsd->output_queue; 11291 sd->output_queue_tailp = oldsd->output_queue_tailp; 11292 oldsd->output_queue = NULL; 11293 oldsd->output_queue_tailp = &oldsd->output_queue; 11294 } 11295 /* Append NAPI poll list from offline CPU, with one exception : 11296 * process_backlog() must be called by cpu owning percpu backlog. 11297 * We properly handle process_queue & input_pkt_queue later. 11298 */ 11299 while (!list_empty(&oldsd->poll_list)) { 11300 struct napi_struct *napi = list_first_entry(&oldsd->poll_list, 11301 struct napi_struct, 11302 poll_list); 11303 11304 list_del_init(&napi->poll_list); 11305 if (napi->poll == process_backlog) 11306 napi->state = 0; 11307 else 11308 ____napi_schedule(sd, napi); 11309 } 11310 11311 raise_softirq_irqoff(NET_TX_SOFTIRQ); 11312 local_irq_enable(); 11313 11314 #ifdef CONFIG_RPS 11315 remsd = oldsd->rps_ipi_list; 11316 oldsd->rps_ipi_list = NULL; 11317 #endif 11318 /* send out pending IPI's on offline CPU */ 11319 net_rps_send_ipi(remsd); 11320 11321 /* Process offline CPU's input_pkt_queue */ 11322 while ((skb = __skb_dequeue(&oldsd->process_queue))) { 11323 netif_rx(skb); 11324 input_queue_head_incr(oldsd); 11325 } 11326 while ((skb = skb_dequeue(&oldsd->input_pkt_queue))) { 11327 netif_rx(skb); 11328 input_queue_head_incr(oldsd); 11329 } 11330 11331 return 0; 11332 } 11333 11334 /** 11335 * netdev_increment_features - increment feature set by one 11336 * @all: current feature set 11337 * @one: new feature set 11338 * @mask: mask feature set 11339 * 11340 * Computes a new feature set after adding a device with feature set 11341 * @one to the master device with current feature set @all. Will not 11342 * enable anything that is off in @mask. Returns the new feature set. 11343 */ 11344 netdev_features_t netdev_increment_features(netdev_features_t all, 11345 netdev_features_t one, netdev_features_t mask) 11346 { 11347 if (mask & NETIF_F_HW_CSUM) 11348 mask |= NETIF_F_CSUM_MASK; 11349 mask |= NETIF_F_VLAN_CHALLENGED; 11350 11351 all |= one & (NETIF_F_ONE_FOR_ALL | NETIF_F_CSUM_MASK) & mask; 11352 all &= one | ~NETIF_F_ALL_FOR_ALL; 11353 11354 /* If one device supports hw checksumming, set for all. */ 11355 if (all & NETIF_F_HW_CSUM) 11356 all &= ~(NETIF_F_CSUM_MASK & ~NETIF_F_HW_CSUM); 11357 11358 return all; 11359 } 11360 EXPORT_SYMBOL(netdev_increment_features); 11361 11362 static struct hlist_head * __net_init netdev_create_hash(void) 11363 { 11364 int i; 11365 struct hlist_head *hash; 11366 11367 hash = kmalloc_array(NETDEV_HASHENTRIES, sizeof(*hash), GFP_KERNEL); 11368 if (hash != NULL) 11369 for (i = 0; i < NETDEV_HASHENTRIES; i++) 11370 INIT_HLIST_HEAD(&hash[i]); 11371 11372 return hash; 11373 } 11374 11375 /* Initialize per network namespace state */ 11376 static int __net_init netdev_init(struct net *net) 11377 { 11378 BUILD_BUG_ON(GRO_HASH_BUCKETS > 11379 8 * sizeof_field(struct napi_struct, gro_bitmask)); 11380 11381 INIT_LIST_HEAD(&net->dev_base_head); 11382 11383 net->dev_name_head = netdev_create_hash(); 11384 if (net->dev_name_head == NULL) 11385 goto err_name; 11386 11387 net->dev_index_head = netdev_create_hash(); 11388 if (net->dev_index_head == NULL) 11389 goto err_idx; 11390 11391 xa_init_flags(&net->dev_by_index, XA_FLAGS_ALLOC1); 11392 11393 RAW_INIT_NOTIFIER_HEAD(&net->netdev_chain); 11394 11395 return 0; 11396 11397 err_idx: 11398 kfree(net->dev_name_head); 11399 err_name: 11400 return -ENOMEM; 11401 } 11402 11403 /** 11404 * netdev_drivername - network driver for the device 11405 * @dev: network device 11406 * 11407 * Determine network driver for device. 11408 */ 11409 const char *netdev_drivername(const struct net_device *dev) 11410 { 11411 const struct device_driver *driver; 11412 const struct device *parent; 11413 const char *empty = ""; 11414 11415 parent = dev->dev.parent; 11416 if (!parent) 11417 return empty; 11418 11419 driver = parent->driver; 11420 if (driver && driver->name) 11421 return driver->name; 11422 return empty; 11423 } 11424 11425 static void __netdev_printk(const char *level, const struct net_device *dev, 11426 struct va_format *vaf) 11427 { 11428 if (dev && dev->dev.parent) { 11429 dev_printk_emit(level[1] - '0', 11430 dev->dev.parent, 11431 "%s %s %s%s: %pV", 11432 dev_driver_string(dev->dev.parent), 11433 dev_name(dev->dev.parent), 11434 netdev_name(dev), netdev_reg_state(dev), 11435 vaf); 11436 } else if (dev) { 11437 printk("%s%s%s: %pV", 11438 level, netdev_name(dev), netdev_reg_state(dev), vaf); 11439 } else { 11440 printk("%s(NULL net_device): %pV", level, vaf); 11441 } 11442 } 11443 11444 void netdev_printk(const char *level, const struct net_device *dev, 11445 const char *format, ...) 11446 { 11447 struct va_format vaf; 11448 va_list args; 11449 11450 va_start(args, format); 11451 11452 vaf.fmt = format; 11453 vaf.va = &args; 11454 11455 __netdev_printk(level, dev, &vaf); 11456 11457 va_end(args); 11458 } 11459 EXPORT_SYMBOL(netdev_printk); 11460 11461 #define define_netdev_printk_level(func, level) \ 11462 void func(const struct net_device *dev, const char *fmt, ...) \ 11463 { \ 11464 struct va_format vaf; \ 11465 va_list args; \ 11466 \ 11467 va_start(args, fmt); \ 11468 \ 11469 vaf.fmt = fmt; \ 11470 vaf.va = &args; \ 11471 \ 11472 __netdev_printk(level, dev, &vaf); \ 11473 \ 11474 va_end(args); \ 11475 } \ 11476 EXPORT_SYMBOL(func); 11477 11478 define_netdev_printk_level(netdev_emerg, KERN_EMERG); 11479 define_netdev_printk_level(netdev_alert, KERN_ALERT); 11480 define_netdev_printk_level(netdev_crit, KERN_CRIT); 11481 define_netdev_printk_level(netdev_err, KERN_ERR); 11482 define_netdev_printk_level(netdev_warn, KERN_WARNING); 11483 define_netdev_printk_level(netdev_notice, KERN_NOTICE); 11484 define_netdev_printk_level(netdev_info, KERN_INFO); 11485 11486 static void __net_exit netdev_exit(struct net *net) 11487 { 11488 kfree(net->dev_name_head); 11489 kfree(net->dev_index_head); 11490 xa_destroy(&net->dev_by_index); 11491 if (net != &init_net) 11492 WARN_ON_ONCE(!list_empty(&net->dev_base_head)); 11493 } 11494 11495 static struct pernet_operations __net_initdata netdev_net_ops = { 11496 .init = netdev_init, 11497 .exit = netdev_exit, 11498 }; 11499 11500 static void __net_exit default_device_exit_net(struct net *net) 11501 { 11502 struct netdev_name_node *name_node, *tmp; 11503 struct net_device *dev, *aux; 11504 /* 11505 * Push all migratable network devices back to the 11506 * initial network namespace 11507 */ 11508 ASSERT_RTNL(); 11509 for_each_netdev_safe(net, dev, aux) { 11510 int err; 11511 char fb_name[IFNAMSIZ]; 11512 11513 /* Ignore unmoveable devices (i.e. loopback) */ 11514 if (dev->features & NETIF_F_NETNS_LOCAL) 11515 continue; 11516 11517 /* Leave virtual devices for the generic cleanup */ 11518 if (dev->rtnl_link_ops && !dev->rtnl_link_ops->netns_refund) 11519 continue; 11520 11521 /* Push remaining network devices to init_net */ 11522 snprintf(fb_name, IFNAMSIZ, "dev%d", dev->ifindex); 11523 if (netdev_name_in_use(&init_net, fb_name)) 11524 snprintf(fb_name, IFNAMSIZ, "dev%%d"); 11525 11526 netdev_for_each_altname_safe(dev, name_node, tmp) 11527 if (netdev_name_in_use(&init_net, name_node->name)) { 11528 netdev_name_node_del(name_node); 11529 synchronize_rcu(); 11530 __netdev_name_node_alt_destroy(name_node); 11531 } 11532 11533 err = dev_change_net_namespace(dev, &init_net, fb_name); 11534 if (err) { 11535 pr_emerg("%s: failed to move %s to init_net: %d\n", 11536 __func__, dev->name, err); 11537 BUG(); 11538 } 11539 } 11540 } 11541 11542 static void __net_exit default_device_exit_batch(struct list_head *net_list) 11543 { 11544 /* At exit all network devices most be removed from a network 11545 * namespace. Do this in the reverse order of registration. 11546 * Do this across as many network namespaces as possible to 11547 * improve batching efficiency. 11548 */ 11549 struct net_device *dev; 11550 struct net *net; 11551 LIST_HEAD(dev_kill_list); 11552 11553 rtnl_lock(); 11554 list_for_each_entry(net, net_list, exit_list) { 11555 default_device_exit_net(net); 11556 cond_resched(); 11557 } 11558 11559 list_for_each_entry(net, net_list, exit_list) { 11560 for_each_netdev_reverse(net, dev) { 11561 if (dev->rtnl_link_ops && dev->rtnl_link_ops->dellink) 11562 dev->rtnl_link_ops->dellink(dev, &dev_kill_list); 11563 else 11564 unregister_netdevice_queue(dev, &dev_kill_list); 11565 } 11566 } 11567 unregister_netdevice_many(&dev_kill_list); 11568 rtnl_unlock(); 11569 } 11570 11571 static struct pernet_operations __net_initdata default_device_ops = { 11572 .exit_batch = default_device_exit_batch, 11573 }; 11574 11575 /* 11576 * Initialize the DEV module. At boot time this walks the device list and 11577 * unhooks any devices that fail to initialise (normally hardware not 11578 * present) and leaves us with a valid list of present and active devices. 11579 * 11580 */ 11581 11582 /* 11583 * This is called single threaded during boot, so no need 11584 * to take the rtnl semaphore. 11585 */ 11586 static int __init net_dev_init(void) 11587 { 11588 int i, rc = -ENOMEM; 11589 11590 BUG_ON(!dev_boot_phase); 11591 11592 if (dev_proc_init()) 11593 goto out; 11594 11595 if (netdev_kobject_init()) 11596 goto out; 11597 11598 INIT_LIST_HEAD(&ptype_all); 11599 for (i = 0; i < PTYPE_HASH_SIZE; i++) 11600 INIT_LIST_HEAD(&ptype_base[i]); 11601 11602 if (register_pernet_subsys(&netdev_net_ops)) 11603 goto out; 11604 11605 /* 11606 * Initialise the packet receive queues. 11607 */ 11608 11609 for_each_possible_cpu(i) { 11610 struct work_struct *flush = per_cpu_ptr(&flush_works, i); 11611 struct softnet_data *sd = &per_cpu(softnet_data, i); 11612 11613 INIT_WORK(flush, flush_backlog); 11614 11615 skb_queue_head_init(&sd->input_pkt_queue); 11616 skb_queue_head_init(&sd->process_queue); 11617 #ifdef CONFIG_XFRM_OFFLOAD 11618 skb_queue_head_init(&sd->xfrm_backlog); 11619 #endif 11620 INIT_LIST_HEAD(&sd->poll_list); 11621 sd->output_queue_tailp = &sd->output_queue; 11622 #ifdef CONFIG_RPS 11623 INIT_CSD(&sd->csd, rps_trigger_softirq, sd); 11624 sd->cpu = i; 11625 #endif 11626 INIT_CSD(&sd->defer_csd, trigger_rx_softirq, sd); 11627 spin_lock_init(&sd->defer_lock); 11628 11629 init_gro_hash(&sd->backlog); 11630 sd->backlog.poll = process_backlog; 11631 sd->backlog.weight = weight_p; 11632 } 11633 11634 dev_boot_phase = 0; 11635 11636 /* The loopback device is special if any other network devices 11637 * is present in a network namespace the loopback device must 11638 * be present. Since we now dynamically allocate and free the 11639 * loopback device ensure this invariant is maintained by 11640 * keeping the loopback device as the first device on the 11641 * list of network devices. Ensuring the loopback devices 11642 * is the first device that appears and the last network device 11643 * that disappears. 11644 */ 11645 if (register_pernet_device(&loopback_net_ops)) 11646 goto out; 11647 11648 if (register_pernet_device(&default_device_ops)) 11649 goto out; 11650 11651 open_softirq(NET_TX_SOFTIRQ, net_tx_action); 11652 open_softirq(NET_RX_SOFTIRQ, net_rx_action); 11653 11654 rc = cpuhp_setup_state_nocalls(CPUHP_NET_DEV_DEAD, "net/dev:dead", 11655 NULL, dev_cpu_dead); 11656 WARN_ON(rc < 0); 11657 rc = 0; 11658 out: 11659 return rc; 11660 } 11661 11662 subsys_initcall(net_dev_init); 11663