1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * NET3 Protocol independent device support routines. 4 * 5 * Derived from the non IP parts of dev.c 1.0.19 6 * Authors: Ross Biro 7 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG> 8 * Mark Evans, <evansmp@uhura.aston.ac.uk> 9 * 10 * Additional Authors: 11 * Florian la Roche <rzsfl@rz.uni-sb.de> 12 * Alan Cox <gw4pts@gw4pts.ampr.org> 13 * David Hinds <dahinds@users.sourceforge.net> 14 * Alexey Kuznetsov <kuznet@ms2.inr.ac.ru> 15 * Adam Sulmicki <adam@cfar.umd.edu> 16 * Pekka Riikonen <priikone@poesidon.pspt.fi> 17 * 18 * Changes: 19 * D.J. Barrow : Fixed bug where dev->refcnt gets set 20 * to 2 if register_netdev gets called 21 * before net_dev_init & also removed a 22 * few lines of code in the process. 23 * Alan Cox : device private ioctl copies fields back. 24 * Alan Cox : Transmit queue code does relevant 25 * stunts to keep the queue safe. 26 * Alan Cox : Fixed double lock. 27 * Alan Cox : Fixed promisc NULL pointer trap 28 * ???????? : Support the full private ioctl range 29 * Alan Cox : Moved ioctl permission check into 30 * drivers 31 * Tim Kordas : SIOCADDMULTI/SIOCDELMULTI 32 * Alan Cox : 100 backlog just doesn't cut it when 33 * you start doing multicast video 8) 34 * Alan Cox : Rewrote net_bh and list manager. 35 * Alan Cox : Fix ETH_P_ALL echoback lengths. 36 * Alan Cox : Took out transmit every packet pass 37 * Saved a few bytes in the ioctl handler 38 * Alan Cox : Network driver sets packet type before 39 * calling netif_rx. Saves a function 40 * call a packet. 41 * Alan Cox : Hashed net_bh() 42 * Richard Kooijman: Timestamp fixes. 43 * Alan Cox : Wrong field in SIOCGIFDSTADDR 44 * Alan Cox : Device lock protection. 45 * Alan Cox : Fixed nasty side effect of device close 46 * changes. 47 * Rudi Cilibrasi : Pass the right thing to 48 * set_mac_address() 49 * Dave Miller : 32bit quantity for the device lock to 50 * make it work out on a Sparc. 51 * Bjorn Ekwall : Added KERNELD hack. 52 * Alan Cox : Cleaned up the backlog initialise. 53 * Craig Metz : SIOCGIFCONF fix if space for under 54 * 1 device. 55 * Thomas Bogendoerfer : Return ENODEV for dev_open, if there 56 * is no device open function. 57 * Andi Kleen : Fix error reporting for SIOCGIFCONF 58 * Michael Chastain : Fix signed/unsigned for SIOCGIFCONF 59 * Cyrus Durgin : Cleaned for KMOD 60 * Adam Sulmicki : Bug Fix : Network Device Unload 61 * A network device unload needs to purge 62 * the backlog queue. 63 * Paul Rusty Russell : SIOCSIFNAME 64 * Pekka Riikonen : Netdev boot-time settings code 65 * Andrew Morton : Make unregister_netdevice wait 66 * indefinitely on dev->refcnt 67 * J Hadi Salim : - Backlog queue sampling 68 * - netif_rx() feedback 69 */ 70 71 #include <linux/uaccess.h> 72 #include <linux/bitops.h> 73 #include <linux/capability.h> 74 #include <linux/cpu.h> 75 #include <linux/types.h> 76 #include <linux/kernel.h> 77 #include <linux/hash.h> 78 #include <linux/slab.h> 79 #include <linux/sched.h> 80 #include <linux/sched/mm.h> 81 #include <linux/mutex.h> 82 #include <linux/rwsem.h> 83 #include <linux/string.h> 84 #include <linux/mm.h> 85 #include <linux/socket.h> 86 #include <linux/sockios.h> 87 #include <linux/errno.h> 88 #include <linux/interrupt.h> 89 #include <linux/if_ether.h> 90 #include <linux/netdevice.h> 91 #include <linux/etherdevice.h> 92 #include <linux/ethtool.h> 93 #include <linux/skbuff.h> 94 #include <linux/kthread.h> 95 #include <linux/bpf.h> 96 #include <linux/bpf_trace.h> 97 #include <net/net_namespace.h> 98 #include <net/sock.h> 99 #include <net/busy_poll.h> 100 #include <linux/rtnetlink.h> 101 #include <linux/stat.h> 102 #include <net/dsa.h> 103 #include <net/dst.h> 104 #include <net/dst_metadata.h> 105 #include <net/gro.h> 106 #include <net/pkt_sched.h> 107 #include <net/pkt_cls.h> 108 #include <net/checksum.h> 109 #include <net/xfrm.h> 110 #include <linux/highmem.h> 111 #include <linux/init.h> 112 #include <linux/module.h> 113 #include <linux/netpoll.h> 114 #include <linux/rcupdate.h> 115 #include <linux/delay.h> 116 #include <net/iw_handler.h> 117 #include <asm/current.h> 118 #include <linux/audit.h> 119 #include <linux/dmaengine.h> 120 #include <linux/err.h> 121 #include <linux/ctype.h> 122 #include <linux/if_arp.h> 123 #include <linux/if_vlan.h> 124 #include <linux/ip.h> 125 #include <net/ip.h> 126 #include <net/mpls.h> 127 #include <linux/ipv6.h> 128 #include <linux/in.h> 129 #include <linux/jhash.h> 130 #include <linux/random.h> 131 #include <trace/events/napi.h> 132 #include <trace/events/net.h> 133 #include <trace/events/skb.h> 134 #include <trace/events/qdisc.h> 135 #include <linux/inetdevice.h> 136 #include <linux/cpu_rmap.h> 137 #include <linux/static_key.h> 138 #include <linux/hashtable.h> 139 #include <linux/vmalloc.h> 140 #include <linux/if_macvlan.h> 141 #include <linux/errqueue.h> 142 #include <linux/hrtimer.h> 143 #include <linux/netfilter_netdev.h> 144 #include <linux/crash_dump.h> 145 #include <linux/sctp.h> 146 #include <net/udp_tunnel.h> 147 #include <linux/net_namespace.h> 148 #include <linux/indirect_call_wrapper.h> 149 #include <net/devlink.h> 150 #include <linux/pm_runtime.h> 151 #include <linux/prandom.h> 152 #include <linux/once_lite.h> 153 154 #include "net-sysfs.h" 155 156 157 static DEFINE_SPINLOCK(ptype_lock); 158 struct list_head ptype_base[PTYPE_HASH_SIZE] __read_mostly; 159 struct list_head ptype_all __read_mostly; /* Taps */ 160 161 static int netif_rx_internal(struct sk_buff *skb); 162 static int call_netdevice_notifiers_info(unsigned long val, 163 struct netdev_notifier_info *info); 164 static int call_netdevice_notifiers_extack(unsigned long val, 165 struct net_device *dev, 166 struct netlink_ext_ack *extack); 167 static struct napi_struct *napi_by_id(unsigned int napi_id); 168 169 /* 170 * The @dev_base_head list is protected by @dev_base_lock and the rtnl 171 * semaphore. 172 * 173 * Pure readers hold dev_base_lock for reading, or rcu_read_lock() 174 * 175 * Writers must hold the rtnl semaphore while they loop through the 176 * dev_base_head list, and hold dev_base_lock for writing when they do the 177 * actual updates. This allows pure readers to access the list even 178 * while a writer is preparing to update it. 179 * 180 * To put it another way, dev_base_lock is held for writing only to 181 * protect against pure readers; the rtnl semaphore provides the 182 * protection against other writers. 183 * 184 * See, for example usages, register_netdevice() and 185 * unregister_netdevice(), which must be called with the rtnl 186 * semaphore held. 187 */ 188 DEFINE_RWLOCK(dev_base_lock); 189 EXPORT_SYMBOL(dev_base_lock); 190 191 static DEFINE_MUTEX(ifalias_mutex); 192 193 /* protects napi_hash addition/deletion and napi_gen_id */ 194 static DEFINE_SPINLOCK(napi_hash_lock); 195 196 static unsigned int napi_gen_id = NR_CPUS; 197 static DEFINE_READ_MOSTLY_HASHTABLE(napi_hash, 8); 198 199 static DECLARE_RWSEM(devnet_rename_sem); 200 201 static inline void dev_base_seq_inc(struct net *net) 202 { 203 while (++net->dev_base_seq == 0) 204 ; 205 } 206 207 static inline struct hlist_head *dev_name_hash(struct net *net, const char *name) 208 { 209 unsigned int hash = full_name_hash(net, name, strnlen(name, IFNAMSIZ)); 210 211 return &net->dev_name_head[hash_32(hash, NETDEV_HASHBITS)]; 212 } 213 214 static inline struct hlist_head *dev_index_hash(struct net *net, int ifindex) 215 { 216 return &net->dev_index_head[ifindex & (NETDEV_HASHENTRIES - 1)]; 217 } 218 219 static inline void rps_lock(struct softnet_data *sd) 220 { 221 #ifdef CONFIG_RPS 222 spin_lock(&sd->input_pkt_queue.lock); 223 #endif 224 } 225 226 static inline void rps_unlock(struct softnet_data *sd) 227 { 228 #ifdef CONFIG_RPS 229 spin_unlock(&sd->input_pkt_queue.lock); 230 #endif 231 } 232 233 static struct netdev_name_node *netdev_name_node_alloc(struct net_device *dev, 234 const char *name) 235 { 236 struct netdev_name_node *name_node; 237 238 name_node = kmalloc(sizeof(*name_node), GFP_KERNEL); 239 if (!name_node) 240 return NULL; 241 INIT_HLIST_NODE(&name_node->hlist); 242 name_node->dev = dev; 243 name_node->name = name; 244 return name_node; 245 } 246 247 static struct netdev_name_node * 248 netdev_name_node_head_alloc(struct net_device *dev) 249 { 250 struct netdev_name_node *name_node; 251 252 name_node = netdev_name_node_alloc(dev, dev->name); 253 if (!name_node) 254 return NULL; 255 INIT_LIST_HEAD(&name_node->list); 256 return name_node; 257 } 258 259 static void netdev_name_node_free(struct netdev_name_node *name_node) 260 { 261 kfree(name_node); 262 } 263 264 static void netdev_name_node_add(struct net *net, 265 struct netdev_name_node *name_node) 266 { 267 hlist_add_head_rcu(&name_node->hlist, 268 dev_name_hash(net, name_node->name)); 269 } 270 271 static void netdev_name_node_del(struct netdev_name_node *name_node) 272 { 273 hlist_del_rcu(&name_node->hlist); 274 } 275 276 static struct netdev_name_node *netdev_name_node_lookup(struct net *net, 277 const char *name) 278 { 279 struct hlist_head *head = dev_name_hash(net, name); 280 struct netdev_name_node *name_node; 281 282 hlist_for_each_entry(name_node, head, hlist) 283 if (!strcmp(name_node->name, name)) 284 return name_node; 285 return NULL; 286 } 287 288 static struct netdev_name_node *netdev_name_node_lookup_rcu(struct net *net, 289 const char *name) 290 { 291 struct hlist_head *head = dev_name_hash(net, name); 292 struct netdev_name_node *name_node; 293 294 hlist_for_each_entry_rcu(name_node, head, hlist) 295 if (!strcmp(name_node->name, name)) 296 return name_node; 297 return NULL; 298 } 299 300 bool netdev_name_in_use(struct net *net, const char *name) 301 { 302 return netdev_name_node_lookup(net, name); 303 } 304 EXPORT_SYMBOL(netdev_name_in_use); 305 306 int netdev_name_node_alt_create(struct net_device *dev, const char *name) 307 { 308 struct netdev_name_node *name_node; 309 struct net *net = dev_net(dev); 310 311 name_node = netdev_name_node_lookup(net, name); 312 if (name_node) 313 return -EEXIST; 314 name_node = netdev_name_node_alloc(dev, name); 315 if (!name_node) 316 return -ENOMEM; 317 netdev_name_node_add(net, name_node); 318 /* The node that holds dev->name acts as a head of per-device list. */ 319 list_add_tail(&name_node->list, &dev->name_node->list); 320 321 return 0; 322 } 323 EXPORT_SYMBOL(netdev_name_node_alt_create); 324 325 static void __netdev_name_node_alt_destroy(struct netdev_name_node *name_node) 326 { 327 list_del(&name_node->list); 328 netdev_name_node_del(name_node); 329 kfree(name_node->name); 330 netdev_name_node_free(name_node); 331 } 332 333 int netdev_name_node_alt_destroy(struct net_device *dev, const char *name) 334 { 335 struct netdev_name_node *name_node; 336 struct net *net = dev_net(dev); 337 338 name_node = netdev_name_node_lookup(net, name); 339 if (!name_node) 340 return -ENOENT; 341 /* lookup might have found our primary name or a name belonging 342 * to another device. 343 */ 344 if (name_node == dev->name_node || name_node->dev != dev) 345 return -EINVAL; 346 347 __netdev_name_node_alt_destroy(name_node); 348 349 return 0; 350 } 351 EXPORT_SYMBOL(netdev_name_node_alt_destroy); 352 353 static void netdev_name_node_alt_flush(struct net_device *dev) 354 { 355 struct netdev_name_node *name_node, *tmp; 356 357 list_for_each_entry_safe(name_node, tmp, &dev->name_node->list, list) 358 __netdev_name_node_alt_destroy(name_node); 359 } 360 361 /* Device list insertion */ 362 static void list_netdevice(struct net_device *dev) 363 { 364 struct net *net = dev_net(dev); 365 366 ASSERT_RTNL(); 367 368 write_lock_bh(&dev_base_lock); 369 list_add_tail_rcu(&dev->dev_list, &net->dev_base_head); 370 netdev_name_node_add(net, dev->name_node); 371 hlist_add_head_rcu(&dev->index_hlist, 372 dev_index_hash(net, dev->ifindex)); 373 write_unlock_bh(&dev_base_lock); 374 375 dev_base_seq_inc(net); 376 } 377 378 /* Device list removal 379 * caller must respect a RCU grace period before freeing/reusing dev 380 */ 381 static void unlist_netdevice(struct net_device *dev) 382 { 383 ASSERT_RTNL(); 384 385 /* Unlink dev from the device chain */ 386 write_lock_bh(&dev_base_lock); 387 list_del_rcu(&dev->dev_list); 388 netdev_name_node_del(dev->name_node); 389 hlist_del_rcu(&dev->index_hlist); 390 write_unlock_bh(&dev_base_lock); 391 392 dev_base_seq_inc(dev_net(dev)); 393 } 394 395 /* 396 * Our notifier list 397 */ 398 399 static RAW_NOTIFIER_HEAD(netdev_chain); 400 401 /* 402 * Device drivers call our routines to queue packets here. We empty the 403 * queue in the local softnet handler. 404 */ 405 406 DEFINE_PER_CPU_ALIGNED(struct softnet_data, softnet_data); 407 EXPORT_PER_CPU_SYMBOL(softnet_data); 408 409 #ifdef CONFIG_LOCKDEP 410 /* 411 * register_netdevice() inits txq->_xmit_lock and sets lockdep class 412 * according to dev->type 413 */ 414 static const unsigned short netdev_lock_type[] = { 415 ARPHRD_NETROM, ARPHRD_ETHER, ARPHRD_EETHER, ARPHRD_AX25, 416 ARPHRD_PRONET, ARPHRD_CHAOS, ARPHRD_IEEE802, ARPHRD_ARCNET, 417 ARPHRD_APPLETLK, ARPHRD_DLCI, ARPHRD_ATM, ARPHRD_METRICOM, 418 ARPHRD_IEEE1394, ARPHRD_EUI64, ARPHRD_INFINIBAND, ARPHRD_SLIP, 419 ARPHRD_CSLIP, ARPHRD_SLIP6, ARPHRD_CSLIP6, ARPHRD_RSRVD, 420 ARPHRD_ADAPT, ARPHRD_ROSE, ARPHRD_X25, ARPHRD_HWX25, 421 ARPHRD_PPP, ARPHRD_CISCO, ARPHRD_LAPB, ARPHRD_DDCMP, 422 ARPHRD_RAWHDLC, ARPHRD_TUNNEL, ARPHRD_TUNNEL6, ARPHRD_FRAD, 423 ARPHRD_SKIP, ARPHRD_LOOPBACK, ARPHRD_LOCALTLK, ARPHRD_FDDI, 424 ARPHRD_BIF, ARPHRD_SIT, ARPHRD_IPDDP, ARPHRD_IPGRE, 425 ARPHRD_PIMREG, ARPHRD_HIPPI, ARPHRD_ASH, ARPHRD_ECONET, 426 ARPHRD_IRDA, ARPHRD_FCPP, ARPHRD_FCAL, ARPHRD_FCPL, 427 ARPHRD_FCFABRIC, ARPHRD_IEEE80211, ARPHRD_IEEE80211_PRISM, 428 ARPHRD_IEEE80211_RADIOTAP, ARPHRD_PHONET, ARPHRD_PHONET_PIPE, 429 ARPHRD_IEEE802154, ARPHRD_VOID, ARPHRD_NONE}; 430 431 static const char *const netdev_lock_name[] = { 432 "_xmit_NETROM", "_xmit_ETHER", "_xmit_EETHER", "_xmit_AX25", 433 "_xmit_PRONET", "_xmit_CHAOS", "_xmit_IEEE802", "_xmit_ARCNET", 434 "_xmit_APPLETLK", "_xmit_DLCI", "_xmit_ATM", "_xmit_METRICOM", 435 "_xmit_IEEE1394", "_xmit_EUI64", "_xmit_INFINIBAND", "_xmit_SLIP", 436 "_xmit_CSLIP", "_xmit_SLIP6", "_xmit_CSLIP6", "_xmit_RSRVD", 437 "_xmit_ADAPT", "_xmit_ROSE", "_xmit_X25", "_xmit_HWX25", 438 "_xmit_PPP", "_xmit_CISCO", "_xmit_LAPB", "_xmit_DDCMP", 439 "_xmit_RAWHDLC", "_xmit_TUNNEL", "_xmit_TUNNEL6", "_xmit_FRAD", 440 "_xmit_SKIP", "_xmit_LOOPBACK", "_xmit_LOCALTLK", "_xmit_FDDI", 441 "_xmit_BIF", "_xmit_SIT", "_xmit_IPDDP", "_xmit_IPGRE", 442 "_xmit_PIMREG", "_xmit_HIPPI", "_xmit_ASH", "_xmit_ECONET", 443 "_xmit_IRDA", "_xmit_FCPP", "_xmit_FCAL", "_xmit_FCPL", 444 "_xmit_FCFABRIC", "_xmit_IEEE80211", "_xmit_IEEE80211_PRISM", 445 "_xmit_IEEE80211_RADIOTAP", "_xmit_PHONET", "_xmit_PHONET_PIPE", 446 "_xmit_IEEE802154", "_xmit_VOID", "_xmit_NONE"}; 447 448 static struct lock_class_key netdev_xmit_lock_key[ARRAY_SIZE(netdev_lock_type)]; 449 static struct lock_class_key netdev_addr_lock_key[ARRAY_SIZE(netdev_lock_type)]; 450 451 static inline unsigned short netdev_lock_pos(unsigned short dev_type) 452 { 453 int i; 454 455 for (i = 0; i < ARRAY_SIZE(netdev_lock_type); i++) 456 if (netdev_lock_type[i] == dev_type) 457 return i; 458 /* the last key is used by default */ 459 return ARRAY_SIZE(netdev_lock_type) - 1; 460 } 461 462 static inline void netdev_set_xmit_lockdep_class(spinlock_t *lock, 463 unsigned short dev_type) 464 { 465 int i; 466 467 i = netdev_lock_pos(dev_type); 468 lockdep_set_class_and_name(lock, &netdev_xmit_lock_key[i], 469 netdev_lock_name[i]); 470 } 471 472 static inline void netdev_set_addr_lockdep_class(struct net_device *dev) 473 { 474 int i; 475 476 i = netdev_lock_pos(dev->type); 477 lockdep_set_class_and_name(&dev->addr_list_lock, 478 &netdev_addr_lock_key[i], 479 netdev_lock_name[i]); 480 } 481 #else 482 static inline void netdev_set_xmit_lockdep_class(spinlock_t *lock, 483 unsigned short dev_type) 484 { 485 } 486 487 static inline void netdev_set_addr_lockdep_class(struct net_device *dev) 488 { 489 } 490 #endif 491 492 /******************************************************************************* 493 * 494 * Protocol management and registration routines 495 * 496 *******************************************************************************/ 497 498 499 /* 500 * Add a protocol ID to the list. Now that the input handler is 501 * smarter we can dispense with all the messy stuff that used to be 502 * here. 503 * 504 * BEWARE!!! Protocol handlers, mangling input packets, 505 * MUST BE last in hash buckets and checking protocol handlers 506 * MUST start from promiscuous ptype_all chain in net_bh. 507 * It is true now, do not change it. 508 * Explanation follows: if protocol handler, mangling packet, will 509 * be the first on list, it is not able to sense, that packet 510 * is cloned and should be copied-on-write, so that it will 511 * change it and subsequent readers will get broken packet. 512 * --ANK (980803) 513 */ 514 515 static inline struct list_head *ptype_head(const struct packet_type *pt) 516 { 517 if (pt->type == htons(ETH_P_ALL)) 518 return pt->dev ? &pt->dev->ptype_all : &ptype_all; 519 else 520 return pt->dev ? &pt->dev->ptype_specific : 521 &ptype_base[ntohs(pt->type) & PTYPE_HASH_MASK]; 522 } 523 524 /** 525 * dev_add_pack - add packet handler 526 * @pt: packet type declaration 527 * 528 * Add a protocol handler to the networking stack. The passed &packet_type 529 * is linked into kernel lists and may not be freed until it has been 530 * removed from the kernel lists. 531 * 532 * This call does not sleep therefore it can not 533 * guarantee all CPU's that are in middle of receiving packets 534 * will see the new packet type (until the next received packet). 535 */ 536 537 void dev_add_pack(struct packet_type *pt) 538 { 539 struct list_head *head = ptype_head(pt); 540 541 spin_lock(&ptype_lock); 542 list_add_rcu(&pt->list, head); 543 spin_unlock(&ptype_lock); 544 } 545 EXPORT_SYMBOL(dev_add_pack); 546 547 /** 548 * __dev_remove_pack - remove packet handler 549 * @pt: packet type declaration 550 * 551 * Remove a protocol handler that was previously added to the kernel 552 * protocol handlers by dev_add_pack(). The passed &packet_type is removed 553 * from the kernel lists and can be freed or reused once this function 554 * returns. 555 * 556 * The packet type might still be in use by receivers 557 * and must not be freed until after all the CPU's have gone 558 * through a quiescent state. 559 */ 560 void __dev_remove_pack(struct packet_type *pt) 561 { 562 struct list_head *head = ptype_head(pt); 563 struct packet_type *pt1; 564 565 spin_lock(&ptype_lock); 566 567 list_for_each_entry(pt1, head, list) { 568 if (pt == pt1) { 569 list_del_rcu(&pt->list); 570 goto out; 571 } 572 } 573 574 pr_warn("dev_remove_pack: %p not found\n", pt); 575 out: 576 spin_unlock(&ptype_lock); 577 } 578 EXPORT_SYMBOL(__dev_remove_pack); 579 580 /** 581 * dev_remove_pack - remove packet handler 582 * @pt: packet type declaration 583 * 584 * Remove a protocol handler that was previously added to the kernel 585 * protocol handlers by dev_add_pack(). The passed &packet_type is removed 586 * from the kernel lists and can be freed or reused once this function 587 * returns. 588 * 589 * This call sleeps to guarantee that no CPU is looking at the packet 590 * type after return. 591 */ 592 void dev_remove_pack(struct packet_type *pt) 593 { 594 __dev_remove_pack(pt); 595 596 synchronize_net(); 597 } 598 EXPORT_SYMBOL(dev_remove_pack); 599 600 601 /******************************************************************************* 602 * 603 * Device Interface Subroutines 604 * 605 *******************************************************************************/ 606 607 /** 608 * dev_get_iflink - get 'iflink' value of a interface 609 * @dev: targeted interface 610 * 611 * Indicates the ifindex the interface is linked to. 612 * Physical interfaces have the same 'ifindex' and 'iflink' values. 613 */ 614 615 int dev_get_iflink(const struct net_device *dev) 616 { 617 if (dev->netdev_ops && dev->netdev_ops->ndo_get_iflink) 618 return dev->netdev_ops->ndo_get_iflink(dev); 619 620 return dev->ifindex; 621 } 622 EXPORT_SYMBOL(dev_get_iflink); 623 624 /** 625 * dev_fill_metadata_dst - Retrieve tunnel egress information. 626 * @dev: targeted interface 627 * @skb: The packet. 628 * 629 * For better visibility of tunnel traffic OVS needs to retrieve 630 * egress tunnel information for a packet. Following API allows 631 * user to get this info. 632 */ 633 int dev_fill_metadata_dst(struct net_device *dev, struct sk_buff *skb) 634 { 635 struct ip_tunnel_info *info; 636 637 if (!dev->netdev_ops || !dev->netdev_ops->ndo_fill_metadata_dst) 638 return -EINVAL; 639 640 info = skb_tunnel_info_unclone(skb); 641 if (!info) 642 return -ENOMEM; 643 if (unlikely(!(info->mode & IP_TUNNEL_INFO_TX))) 644 return -EINVAL; 645 646 return dev->netdev_ops->ndo_fill_metadata_dst(dev, skb); 647 } 648 EXPORT_SYMBOL_GPL(dev_fill_metadata_dst); 649 650 static struct net_device_path *dev_fwd_path(struct net_device_path_stack *stack) 651 { 652 int k = stack->num_paths++; 653 654 if (WARN_ON_ONCE(k >= NET_DEVICE_PATH_STACK_MAX)) 655 return NULL; 656 657 return &stack->path[k]; 658 } 659 660 int dev_fill_forward_path(const struct net_device *dev, const u8 *daddr, 661 struct net_device_path_stack *stack) 662 { 663 const struct net_device *last_dev; 664 struct net_device_path_ctx ctx = { 665 .dev = dev, 666 .daddr = daddr, 667 }; 668 struct net_device_path *path; 669 int ret = 0; 670 671 stack->num_paths = 0; 672 while (ctx.dev && ctx.dev->netdev_ops->ndo_fill_forward_path) { 673 last_dev = ctx.dev; 674 path = dev_fwd_path(stack); 675 if (!path) 676 return -1; 677 678 memset(path, 0, sizeof(struct net_device_path)); 679 ret = ctx.dev->netdev_ops->ndo_fill_forward_path(&ctx, path); 680 if (ret < 0) 681 return -1; 682 683 if (WARN_ON_ONCE(last_dev == ctx.dev)) 684 return -1; 685 } 686 path = dev_fwd_path(stack); 687 if (!path) 688 return -1; 689 path->type = DEV_PATH_ETHERNET; 690 path->dev = ctx.dev; 691 692 return ret; 693 } 694 EXPORT_SYMBOL_GPL(dev_fill_forward_path); 695 696 /** 697 * __dev_get_by_name - find a device by its name 698 * @net: the applicable net namespace 699 * @name: name to find 700 * 701 * Find an interface by name. Must be called under RTNL semaphore 702 * or @dev_base_lock. If the name is found a pointer to the device 703 * is returned. If the name is not found then %NULL is returned. The 704 * reference counters are not incremented so the caller must be 705 * careful with locks. 706 */ 707 708 struct net_device *__dev_get_by_name(struct net *net, const char *name) 709 { 710 struct netdev_name_node *node_name; 711 712 node_name = netdev_name_node_lookup(net, name); 713 return node_name ? node_name->dev : NULL; 714 } 715 EXPORT_SYMBOL(__dev_get_by_name); 716 717 /** 718 * dev_get_by_name_rcu - find a device by its name 719 * @net: the applicable net namespace 720 * @name: name to find 721 * 722 * Find an interface by name. 723 * If the name is found a pointer to the device is returned. 724 * If the name is not found then %NULL is returned. 725 * The reference counters are not incremented so the caller must be 726 * careful with locks. The caller must hold RCU lock. 727 */ 728 729 struct net_device *dev_get_by_name_rcu(struct net *net, const char *name) 730 { 731 struct netdev_name_node *node_name; 732 733 node_name = netdev_name_node_lookup_rcu(net, name); 734 return node_name ? node_name->dev : NULL; 735 } 736 EXPORT_SYMBOL(dev_get_by_name_rcu); 737 738 /** 739 * dev_get_by_name - find a device by its name 740 * @net: the applicable net namespace 741 * @name: name to find 742 * 743 * Find an interface by name. This can be called from any 744 * context and does its own locking. The returned handle has 745 * the usage count incremented and the caller must use dev_put() to 746 * release it when it is no longer needed. %NULL is returned if no 747 * matching device is found. 748 */ 749 750 struct net_device *dev_get_by_name(struct net *net, const char *name) 751 { 752 struct net_device *dev; 753 754 rcu_read_lock(); 755 dev = dev_get_by_name_rcu(net, name); 756 dev_hold(dev); 757 rcu_read_unlock(); 758 return dev; 759 } 760 EXPORT_SYMBOL(dev_get_by_name); 761 762 /** 763 * __dev_get_by_index - find a device by its ifindex 764 * @net: the applicable net namespace 765 * @ifindex: index of device 766 * 767 * Search for an interface by index. Returns %NULL if the device 768 * is not found or a pointer to the device. The device has not 769 * had its reference counter increased so the caller must be careful 770 * about locking. The caller must hold either the RTNL semaphore 771 * or @dev_base_lock. 772 */ 773 774 struct net_device *__dev_get_by_index(struct net *net, int ifindex) 775 { 776 struct net_device *dev; 777 struct hlist_head *head = dev_index_hash(net, ifindex); 778 779 hlist_for_each_entry(dev, head, index_hlist) 780 if (dev->ifindex == ifindex) 781 return dev; 782 783 return NULL; 784 } 785 EXPORT_SYMBOL(__dev_get_by_index); 786 787 /** 788 * dev_get_by_index_rcu - find a device by its ifindex 789 * @net: the applicable net namespace 790 * @ifindex: index of device 791 * 792 * Search for an interface by index. Returns %NULL if the device 793 * is not found or a pointer to the device. The device has not 794 * had its reference counter increased so the caller must be careful 795 * about locking. The caller must hold RCU lock. 796 */ 797 798 struct net_device *dev_get_by_index_rcu(struct net *net, int ifindex) 799 { 800 struct net_device *dev; 801 struct hlist_head *head = dev_index_hash(net, ifindex); 802 803 hlist_for_each_entry_rcu(dev, head, index_hlist) 804 if (dev->ifindex == ifindex) 805 return dev; 806 807 return NULL; 808 } 809 EXPORT_SYMBOL(dev_get_by_index_rcu); 810 811 812 /** 813 * dev_get_by_index - find a device by its ifindex 814 * @net: the applicable net namespace 815 * @ifindex: index of device 816 * 817 * Search for an interface by index. Returns NULL if the device 818 * is not found or a pointer to the device. The device returned has 819 * had a reference added and the pointer is safe until the user calls 820 * dev_put to indicate they have finished with it. 821 */ 822 823 struct net_device *dev_get_by_index(struct net *net, int ifindex) 824 { 825 struct net_device *dev; 826 827 rcu_read_lock(); 828 dev = dev_get_by_index_rcu(net, ifindex); 829 dev_hold(dev); 830 rcu_read_unlock(); 831 return dev; 832 } 833 EXPORT_SYMBOL(dev_get_by_index); 834 835 /** 836 * dev_get_by_napi_id - find a device by napi_id 837 * @napi_id: ID of the NAPI struct 838 * 839 * Search for an interface by NAPI ID. Returns %NULL if the device 840 * is not found or a pointer to the device. The device has not had 841 * its reference counter increased so the caller must be careful 842 * about locking. The caller must hold RCU lock. 843 */ 844 845 struct net_device *dev_get_by_napi_id(unsigned int napi_id) 846 { 847 struct napi_struct *napi; 848 849 WARN_ON_ONCE(!rcu_read_lock_held()); 850 851 if (napi_id < MIN_NAPI_ID) 852 return NULL; 853 854 napi = napi_by_id(napi_id); 855 856 return napi ? napi->dev : NULL; 857 } 858 EXPORT_SYMBOL(dev_get_by_napi_id); 859 860 /** 861 * netdev_get_name - get a netdevice name, knowing its ifindex. 862 * @net: network namespace 863 * @name: a pointer to the buffer where the name will be stored. 864 * @ifindex: the ifindex of the interface to get the name from. 865 */ 866 int netdev_get_name(struct net *net, char *name, int ifindex) 867 { 868 struct net_device *dev; 869 int ret; 870 871 down_read(&devnet_rename_sem); 872 rcu_read_lock(); 873 874 dev = dev_get_by_index_rcu(net, ifindex); 875 if (!dev) { 876 ret = -ENODEV; 877 goto out; 878 } 879 880 strcpy(name, dev->name); 881 882 ret = 0; 883 out: 884 rcu_read_unlock(); 885 up_read(&devnet_rename_sem); 886 return ret; 887 } 888 889 /** 890 * dev_getbyhwaddr_rcu - find a device by its hardware address 891 * @net: the applicable net namespace 892 * @type: media type of device 893 * @ha: hardware address 894 * 895 * Search for an interface by MAC address. Returns NULL if the device 896 * is not found or a pointer to the device. 897 * The caller must hold RCU or RTNL. 898 * The returned device has not had its ref count increased 899 * and the caller must therefore be careful about locking 900 * 901 */ 902 903 struct net_device *dev_getbyhwaddr_rcu(struct net *net, unsigned short type, 904 const char *ha) 905 { 906 struct net_device *dev; 907 908 for_each_netdev_rcu(net, dev) 909 if (dev->type == type && 910 !memcmp(dev->dev_addr, ha, dev->addr_len)) 911 return dev; 912 913 return NULL; 914 } 915 EXPORT_SYMBOL(dev_getbyhwaddr_rcu); 916 917 struct net_device *dev_getfirstbyhwtype(struct net *net, unsigned short type) 918 { 919 struct net_device *dev, *ret = NULL; 920 921 rcu_read_lock(); 922 for_each_netdev_rcu(net, dev) 923 if (dev->type == type) { 924 dev_hold(dev); 925 ret = dev; 926 break; 927 } 928 rcu_read_unlock(); 929 return ret; 930 } 931 EXPORT_SYMBOL(dev_getfirstbyhwtype); 932 933 /** 934 * __dev_get_by_flags - find any device with given flags 935 * @net: the applicable net namespace 936 * @if_flags: IFF_* values 937 * @mask: bitmask of bits in if_flags to check 938 * 939 * Search for any interface with the given flags. Returns NULL if a device 940 * is not found or a pointer to the device. Must be called inside 941 * rtnl_lock(), and result refcount is unchanged. 942 */ 943 944 struct net_device *__dev_get_by_flags(struct net *net, unsigned short if_flags, 945 unsigned short mask) 946 { 947 struct net_device *dev, *ret; 948 949 ASSERT_RTNL(); 950 951 ret = NULL; 952 for_each_netdev(net, dev) { 953 if (((dev->flags ^ if_flags) & mask) == 0) { 954 ret = dev; 955 break; 956 } 957 } 958 return ret; 959 } 960 EXPORT_SYMBOL(__dev_get_by_flags); 961 962 /** 963 * dev_valid_name - check if name is okay for network device 964 * @name: name string 965 * 966 * Network device names need to be valid file names to 967 * allow sysfs to work. We also disallow any kind of 968 * whitespace. 969 */ 970 bool dev_valid_name(const char *name) 971 { 972 if (*name == '\0') 973 return false; 974 if (strnlen(name, IFNAMSIZ) == IFNAMSIZ) 975 return false; 976 if (!strcmp(name, ".") || !strcmp(name, "..")) 977 return false; 978 979 while (*name) { 980 if (*name == '/' || *name == ':' || isspace(*name)) 981 return false; 982 name++; 983 } 984 return true; 985 } 986 EXPORT_SYMBOL(dev_valid_name); 987 988 /** 989 * __dev_alloc_name - allocate a name for a device 990 * @net: network namespace to allocate the device name in 991 * @name: name format string 992 * @buf: scratch buffer and result name string 993 * 994 * Passed a format string - eg "lt%d" it will try and find a suitable 995 * id. It scans list of devices to build up a free map, then chooses 996 * the first empty slot. The caller must hold the dev_base or rtnl lock 997 * while allocating the name and adding the device in order to avoid 998 * duplicates. 999 * Limited to bits_per_byte * page size devices (ie 32K on most platforms). 1000 * Returns the number of the unit assigned or a negative errno code. 1001 */ 1002 1003 static int __dev_alloc_name(struct net *net, const char *name, char *buf) 1004 { 1005 int i = 0; 1006 const char *p; 1007 const int max_netdevices = 8*PAGE_SIZE; 1008 unsigned long *inuse; 1009 struct net_device *d; 1010 1011 if (!dev_valid_name(name)) 1012 return -EINVAL; 1013 1014 p = strchr(name, '%'); 1015 if (p) { 1016 /* 1017 * Verify the string as this thing may have come from 1018 * the user. There must be either one "%d" and no other "%" 1019 * characters. 1020 */ 1021 if (p[1] != 'd' || strchr(p + 2, '%')) 1022 return -EINVAL; 1023 1024 /* Use one page as a bit array of possible slots */ 1025 inuse = (unsigned long *) get_zeroed_page(GFP_ATOMIC); 1026 if (!inuse) 1027 return -ENOMEM; 1028 1029 for_each_netdev(net, d) { 1030 struct netdev_name_node *name_node; 1031 list_for_each_entry(name_node, &d->name_node->list, list) { 1032 if (!sscanf(name_node->name, name, &i)) 1033 continue; 1034 if (i < 0 || i >= max_netdevices) 1035 continue; 1036 1037 /* avoid cases where sscanf is not exact inverse of printf */ 1038 snprintf(buf, IFNAMSIZ, name, i); 1039 if (!strncmp(buf, name_node->name, IFNAMSIZ)) 1040 set_bit(i, inuse); 1041 } 1042 if (!sscanf(d->name, name, &i)) 1043 continue; 1044 if (i < 0 || i >= max_netdevices) 1045 continue; 1046 1047 /* avoid cases where sscanf is not exact inverse of printf */ 1048 snprintf(buf, IFNAMSIZ, name, i); 1049 if (!strncmp(buf, d->name, IFNAMSIZ)) 1050 set_bit(i, inuse); 1051 } 1052 1053 i = find_first_zero_bit(inuse, max_netdevices); 1054 free_page((unsigned long) inuse); 1055 } 1056 1057 snprintf(buf, IFNAMSIZ, name, i); 1058 if (!netdev_name_in_use(net, buf)) 1059 return i; 1060 1061 /* It is possible to run out of possible slots 1062 * when the name is long and there isn't enough space left 1063 * for the digits, or if all bits are used. 1064 */ 1065 return -ENFILE; 1066 } 1067 1068 static int dev_alloc_name_ns(struct net *net, 1069 struct net_device *dev, 1070 const char *name) 1071 { 1072 char buf[IFNAMSIZ]; 1073 int ret; 1074 1075 BUG_ON(!net); 1076 ret = __dev_alloc_name(net, name, buf); 1077 if (ret >= 0) 1078 strlcpy(dev->name, buf, IFNAMSIZ); 1079 return ret; 1080 } 1081 1082 /** 1083 * dev_alloc_name - allocate a name for a device 1084 * @dev: device 1085 * @name: name format string 1086 * 1087 * Passed a format string - eg "lt%d" it will try and find a suitable 1088 * id. It scans list of devices to build up a free map, then chooses 1089 * the first empty slot. The caller must hold the dev_base or rtnl lock 1090 * while allocating the name and adding the device in order to avoid 1091 * duplicates. 1092 * Limited to bits_per_byte * page size devices (ie 32K on most platforms). 1093 * Returns the number of the unit assigned or a negative errno code. 1094 */ 1095 1096 int dev_alloc_name(struct net_device *dev, const char *name) 1097 { 1098 return dev_alloc_name_ns(dev_net(dev), dev, name); 1099 } 1100 EXPORT_SYMBOL(dev_alloc_name); 1101 1102 static int dev_get_valid_name(struct net *net, struct net_device *dev, 1103 const char *name) 1104 { 1105 BUG_ON(!net); 1106 1107 if (!dev_valid_name(name)) 1108 return -EINVAL; 1109 1110 if (strchr(name, '%')) 1111 return dev_alloc_name_ns(net, dev, name); 1112 else if (netdev_name_in_use(net, name)) 1113 return -EEXIST; 1114 else if (dev->name != name) 1115 strlcpy(dev->name, name, IFNAMSIZ); 1116 1117 return 0; 1118 } 1119 1120 /** 1121 * dev_change_name - change name of a device 1122 * @dev: device 1123 * @newname: name (or format string) must be at least IFNAMSIZ 1124 * 1125 * Change name of a device, can pass format strings "eth%d". 1126 * for wildcarding. 1127 */ 1128 int dev_change_name(struct net_device *dev, const char *newname) 1129 { 1130 unsigned char old_assign_type; 1131 char oldname[IFNAMSIZ]; 1132 int err = 0; 1133 int ret; 1134 struct net *net; 1135 1136 ASSERT_RTNL(); 1137 BUG_ON(!dev_net(dev)); 1138 1139 net = dev_net(dev); 1140 1141 /* Some auto-enslaved devices e.g. failover slaves are 1142 * special, as userspace might rename the device after 1143 * the interface had been brought up and running since 1144 * the point kernel initiated auto-enslavement. Allow 1145 * live name change even when these slave devices are 1146 * up and running. 1147 * 1148 * Typically, users of these auto-enslaving devices 1149 * don't actually care about slave name change, as 1150 * they are supposed to operate on master interface 1151 * directly. 1152 */ 1153 if (dev->flags & IFF_UP && 1154 likely(!(dev->priv_flags & IFF_LIVE_RENAME_OK))) 1155 return -EBUSY; 1156 1157 down_write(&devnet_rename_sem); 1158 1159 if (strncmp(newname, dev->name, IFNAMSIZ) == 0) { 1160 up_write(&devnet_rename_sem); 1161 return 0; 1162 } 1163 1164 memcpy(oldname, dev->name, IFNAMSIZ); 1165 1166 err = dev_get_valid_name(net, dev, newname); 1167 if (err < 0) { 1168 up_write(&devnet_rename_sem); 1169 return err; 1170 } 1171 1172 if (oldname[0] && !strchr(oldname, '%')) 1173 netdev_info(dev, "renamed from %s\n", oldname); 1174 1175 old_assign_type = dev->name_assign_type; 1176 dev->name_assign_type = NET_NAME_RENAMED; 1177 1178 rollback: 1179 ret = device_rename(&dev->dev, dev->name); 1180 if (ret) { 1181 memcpy(dev->name, oldname, IFNAMSIZ); 1182 dev->name_assign_type = old_assign_type; 1183 up_write(&devnet_rename_sem); 1184 return ret; 1185 } 1186 1187 up_write(&devnet_rename_sem); 1188 1189 netdev_adjacent_rename_links(dev, oldname); 1190 1191 write_lock_bh(&dev_base_lock); 1192 netdev_name_node_del(dev->name_node); 1193 write_unlock_bh(&dev_base_lock); 1194 1195 synchronize_rcu(); 1196 1197 write_lock_bh(&dev_base_lock); 1198 netdev_name_node_add(net, dev->name_node); 1199 write_unlock_bh(&dev_base_lock); 1200 1201 ret = call_netdevice_notifiers(NETDEV_CHANGENAME, dev); 1202 ret = notifier_to_errno(ret); 1203 1204 if (ret) { 1205 /* err >= 0 after dev_alloc_name() or stores the first errno */ 1206 if (err >= 0) { 1207 err = ret; 1208 down_write(&devnet_rename_sem); 1209 memcpy(dev->name, oldname, IFNAMSIZ); 1210 memcpy(oldname, newname, IFNAMSIZ); 1211 dev->name_assign_type = old_assign_type; 1212 old_assign_type = NET_NAME_RENAMED; 1213 goto rollback; 1214 } else { 1215 netdev_err(dev, "name change rollback failed: %d\n", 1216 ret); 1217 } 1218 } 1219 1220 return err; 1221 } 1222 1223 /** 1224 * dev_set_alias - change ifalias of a device 1225 * @dev: device 1226 * @alias: name up to IFALIASZ 1227 * @len: limit of bytes to copy from info 1228 * 1229 * Set ifalias for a device, 1230 */ 1231 int dev_set_alias(struct net_device *dev, const char *alias, size_t len) 1232 { 1233 struct dev_ifalias *new_alias = NULL; 1234 1235 if (len >= IFALIASZ) 1236 return -EINVAL; 1237 1238 if (len) { 1239 new_alias = kmalloc(sizeof(*new_alias) + len + 1, GFP_KERNEL); 1240 if (!new_alias) 1241 return -ENOMEM; 1242 1243 memcpy(new_alias->ifalias, alias, len); 1244 new_alias->ifalias[len] = 0; 1245 } 1246 1247 mutex_lock(&ifalias_mutex); 1248 new_alias = rcu_replace_pointer(dev->ifalias, new_alias, 1249 mutex_is_locked(&ifalias_mutex)); 1250 mutex_unlock(&ifalias_mutex); 1251 1252 if (new_alias) 1253 kfree_rcu(new_alias, rcuhead); 1254 1255 return len; 1256 } 1257 EXPORT_SYMBOL(dev_set_alias); 1258 1259 /** 1260 * dev_get_alias - get ifalias of a device 1261 * @dev: device 1262 * @name: buffer to store name of ifalias 1263 * @len: size of buffer 1264 * 1265 * get ifalias for a device. Caller must make sure dev cannot go 1266 * away, e.g. rcu read lock or own a reference count to device. 1267 */ 1268 int dev_get_alias(const struct net_device *dev, char *name, size_t len) 1269 { 1270 const struct dev_ifalias *alias; 1271 int ret = 0; 1272 1273 rcu_read_lock(); 1274 alias = rcu_dereference(dev->ifalias); 1275 if (alias) 1276 ret = snprintf(name, len, "%s", alias->ifalias); 1277 rcu_read_unlock(); 1278 1279 return ret; 1280 } 1281 1282 /** 1283 * netdev_features_change - device changes features 1284 * @dev: device to cause notification 1285 * 1286 * Called to indicate a device has changed features. 1287 */ 1288 void netdev_features_change(struct net_device *dev) 1289 { 1290 call_netdevice_notifiers(NETDEV_FEAT_CHANGE, dev); 1291 } 1292 EXPORT_SYMBOL(netdev_features_change); 1293 1294 /** 1295 * netdev_state_change - device changes state 1296 * @dev: device to cause notification 1297 * 1298 * Called to indicate a device has changed state. This function calls 1299 * the notifier chains for netdev_chain and sends a NEWLINK message 1300 * to the routing socket. 1301 */ 1302 void netdev_state_change(struct net_device *dev) 1303 { 1304 if (dev->flags & IFF_UP) { 1305 struct netdev_notifier_change_info change_info = { 1306 .info.dev = dev, 1307 }; 1308 1309 call_netdevice_notifiers_info(NETDEV_CHANGE, 1310 &change_info.info); 1311 rtmsg_ifinfo(RTM_NEWLINK, dev, 0, GFP_KERNEL); 1312 } 1313 } 1314 EXPORT_SYMBOL(netdev_state_change); 1315 1316 /** 1317 * __netdev_notify_peers - notify network peers about existence of @dev, 1318 * to be called when rtnl lock is already held. 1319 * @dev: network device 1320 * 1321 * Generate traffic such that interested network peers are aware of 1322 * @dev, such as by generating a gratuitous ARP. This may be used when 1323 * a device wants to inform the rest of the network about some sort of 1324 * reconfiguration such as a failover event or virtual machine 1325 * migration. 1326 */ 1327 void __netdev_notify_peers(struct net_device *dev) 1328 { 1329 ASSERT_RTNL(); 1330 call_netdevice_notifiers(NETDEV_NOTIFY_PEERS, dev); 1331 call_netdevice_notifiers(NETDEV_RESEND_IGMP, dev); 1332 } 1333 EXPORT_SYMBOL(__netdev_notify_peers); 1334 1335 /** 1336 * netdev_notify_peers - notify network peers about existence of @dev 1337 * @dev: network device 1338 * 1339 * Generate traffic such that interested network peers are aware of 1340 * @dev, such as by generating a gratuitous ARP. This may be used when 1341 * a device wants to inform the rest of the network about some sort of 1342 * reconfiguration such as a failover event or virtual machine 1343 * migration. 1344 */ 1345 void netdev_notify_peers(struct net_device *dev) 1346 { 1347 rtnl_lock(); 1348 __netdev_notify_peers(dev); 1349 rtnl_unlock(); 1350 } 1351 EXPORT_SYMBOL(netdev_notify_peers); 1352 1353 static int napi_threaded_poll(void *data); 1354 1355 static int napi_kthread_create(struct napi_struct *n) 1356 { 1357 int err = 0; 1358 1359 /* Create and wake up the kthread once to put it in 1360 * TASK_INTERRUPTIBLE mode to avoid the blocked task 1361 * warning and work with loadavg. 1362 */ 1363 n->thread = kthread_run(napi_threaded_poll, n, "napi/%s-%d", 1364 n->dev->name, n->napi_id); 1365 if (IS_ERR(n->thread)) { 1366 err = PTR_ERR(n->thread); 1367 pr_err("kthread_run failed with err %d\n", err); 1368 n->thread = NULL; 1369 } 1370 1371 return err; 1372 } 1373 1374 static int __dev_open(struct net_device *dev, struct netlink_ext_ack *extack) 1375 { 1376 const struct net_device_ops *ops = dev->netdev_ops; 1377 int ret; 1378 1379 ASSERT_RTNL(); 1380 1381 if (!netif_device_present(dev)) { 1382 /* may be detached because parent is runtime-suspended */ 1383 if (dev->dev.parent) 1384 pm_runtime_resume(dev->dev.parent); 1385 if (!netif_device_present(dev)) 1386 return -ENODEV; 1387 } 1388 1389 /* Block netpoll from trying to do any rx path servicing. 1390 * If we don't do this there is a chance ndo_poll_controller 1391 * or ndo_poll may be running while we open the device 1392 */ 1393 netpoll_poll_disable(dev); 1394 1395 ret = call_netdevice_notifiers_extack(NETDEV_PRE_UP, dev, extack); 1396 ret = notifier_to_errno(ret); 1397 if (ret) 1398 return ret; 1399 1400 set_bit(__LINK_STATE_START, &dev->state); 1401 1402 if (ops->ndo_validate_addr) 1403 ret = ops->ndo_validate_addr(dev); 1404 1405 if (!ret && ops->ndo_open) 1406 ret = ops->ndo_open(dev); 1407 1408 netpoll_poll_enable(dev); 1409 1410 if (ret) 1411 clear_bit(__LINK_STATE_START, &dev->state); 1412 else { 1413 dev->flags |= IFF_UP; 1414 dev_set_rx_mode(dev); 1415 dev_activate(dev); 1416 add_device_randomness(dev->dev_addr, dev->addr_len); 1417 } 1418 1419 return ret; 1420 } 1421 1422 /** 1423 * dev_open - prepare an interface for use. 1424 * @dev: device to open 1425 * @extack: netlink extended ack 1426 * 1427 * Takes a device from down to up state. The device's private open 1428 * function is invoked and then the multicast lists are loaded. Finally 1429 * the device is moved into the up state and a %NETDEV_UP message is 1430 * sent to the netdev notifier chain. 1431 * 1432 * Calling this function on an active interface is a nop. On a failure 1433 * a negative errno code is returned. 1434 */ 1435 int dev_open(struct net_device *dev, struct netlink_ext_ack *extack) 1436 { 1437 int ret; 1438 1439 if (dev->flags & IFF_UP) 1440 return 0; 1441 1442 ret = __dev_open(dev, extack); 1443 if (ret < 0) 1444 return ret; 1445 1446 rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP|IFF_RUNNING, GFP_KERNEL); 1447 call_netdevice_notifiers(NETDEV_UP, dev); 1448 1449 return ret; 1450 } 1451 EXPORT_SYMBOL(dev_open); 1452 1453 static void __dev_close_many(struct list_head *head) 1454 { 1455 struct net_device *dev; 1456 1457 ASSERT_RTNL(); 1458 might_sleep(); 1459 1460 list_for_each_entry(dev, head, close_list) { 1461 /* Temporarily disable netpoll until the interface is down */ 1462 netpoll_poll_disable(dev); 1463 1464 call_netdevice_notifiers(NETDEV_GOING_DOWN, dev); 1465 1466 clear_bit(__LINK_STATE_START, &dev->state); 1467 1468 /* Synchronize to scheduled poll. We cannot touch poll list, it 1469 * can be even on different cpu. So just clear netif_running(). 1470 * 1471 * dev->stop() will invoke napi_disable() on all of it's 1472 * napi_struct instances on this device. 1473 */ 1474 smp_mb__after_atomic(); /* Commit netif_running(). */ 1475 } 1476 1477 dev_deactivate_many(head); 1478 1479 list_for_each_entry(dev, head, close_list) { 1480 const struct net_device_ops *ops = dev->netdev_ops; 1481 1482 /* 1483 * Call the device specific close. This cannot fail. 1484 * Only if device is UP 1485 * 1486 * We allow it to be called even after a DETACH hot-plug 1487 * event. 1488 */ 1489 if (ops->ndo_stop) 1490 ops->ndo_stop(dev); 1491 1492 dev->flags &= ~IFF_UP; 1493 netpoll_poll_enable(dev); 1494 } 1495 } 1496 1497 static void __dev_close(struct net_device *dev) 1498 { 1499 LIST_HEAD(single); 1500 1501 list_add(&dev->close_list, &single); 1502 __dev_close_many(&single); 1503 list_del(&single); 1504 } 1505 1506 void dev_close_many(struct list_head *head, bool unlink) 1507 { 1508 struct net_device *dev, *tmp; 1509 1510 /* Remove the devices that don't need to be closed */ 1511 list_for_each_entry_safe(dev, tmp, head, close_list) 1512 if (!(dev->flags & IFF_UP)) 1513 list_del_init(&dev->close_list); 1514 1515 __dev_close_many(head); 1516 1517 list_for_each_entry_safe(dev, tmp, head, close_list) { 1518 rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP|IFF_RUNNING, GFP_KERNEL); 1519 call_netdevice_notifiers(NETDEV_DOWN, dev); 1520 if (unlink) 1521 list_del_init(&dev->close_list); 1522 } 1523 } 1524 EXPORT_SYMBOL(dev_close_many); 1525 1526 /** 1527 * dev_close - shutdown an interface. 1528 * @dev: device to shutdown 1529 * 1530 * This function moves an active device into down state. A 1531 * %NETDEV_GOING_DOWN is sent to the netdev notifier chain. The device 1532 * is then deactivated and finally a %NETDEV_DOWN is sent to the notifier 1533 * chain. 1534 */ 1535 void dev_close(struct net_device *dev) 1536 { 1537 if (dev->flags & IFF_UP) { 1538 LIST_HEAD(single); 1539 1540 list_add(&dev->close_list, &single); 1541 dev_close_many(&single, true); 1542 list_del(&single); 1543 } 1544 } 1545 EXPORT_SYMBOL(dev_close); 1546 1547 1548 /** 1549 * dev_disable_lro - disable Large Receive Offload on a device 1550 * @dev: device 1551 * 1552 * Disable Large Receive Offload (LRO) on a net device. Must be 1553 * called under RTNL. This is needed if received packets may be 1554 * forwarded to another interface. 1555 */ 1556 void dev_disable_lro(struct net_device *dev) 1557 { 1558 struct net_device *lower_dev; 1559 struct list_head *iter; 1560 1561 dev->wanted_features &= ~NETIF_F_LRO; 1562 netdev_update_features(dev); 1563 1564 if (unlikely(dev->features & NETIF_F_LRO)) 1565 netdev_WARN(dev, "failed to disable LRO!\n"); 1566 1567 netdev_for_each_lower_dev(dev, lower_dev, iter) 1568 dev_disable_lro(lower_dev); 1569 } 1570 EXPORT_SYMBOL(dev_disable_lro); 1571 1572 /** 1573 * dev_disable_gro_hw - disable HW Generic Receive Offload on a device 1574 * @dev: device 1575 * 1576 * Disable HW Generic Receive Offload (GRO_HW) on a net device. Must be 1577 * called under RTNL. This is needed if Generic XDP is installed on 1578 * the device. 1579 */ 1580 static void dev_disable_gro_hw(struct net_device *dev) 1581 { 1582 dev->wanted_features &= ~NETIF_F_GRO_HW; 1583 netdev_update_features(dev); 1584 1585 if (unlikely(dev->features & NETIF_F_GRO_HW)) 1586 netdev_WARN(dev, "failed to disable GRO_HW!\n"); 1587 } 1588 1589 const char *netdev_cmd_to_name(enum netdev_cmd cmd) 1590 { 1591 #define N(val) \ 1592 case NETDEV_##val: \ 1593 return "NETDEV_" __stringify(val); 1594 switch (cmd) { 1595 N(UP) N(DOWN) N(REBOOT) N(CHANGE) N(REGISTER) N(UNREGISTER) 1596 N(CHANGEMTU) N(CHANGEADDR) N(GOING_DOWN) N(CHANGENAME) N(FEAT_CHANGE) 1597 N(BONDING_FAILOVER) N(PRE_UP) N(PRE_TYPE_CHANGE) N(POST_TYPE_CHANGE) 1598 N(POST_INIT) N(RELEASE) N(NOTIFY_PEERS) N(JOIN) N(CHANGEUPPER) 1599 N(RESEND_IGMP) N(PRECHANGEMTU) N(CHANGEINFODATA) N(BONDING_INFO) 1600 N(PRECHANGEUPPER) N(CHANGELOWERSTATE) N(UDP_TUNNEL_PUSH_INFO) 1601 N(UDP_TUNNEL_DROP_INFO) N(CHANGE_TX_QUEUE_LEN) 1602 N(CVLAN_FILTER_PUSH_INFO) N(CVLAN_FILTER_DROP_INFO) 1603 N(SVLAN_FILTER_PUSH_INFO) N(SVLAN_FILTER_DROP_INFO) 1604 N(PRE_CHANGEADDR) 1605 } 1606 #undef N 1607 return "UNKNOWN_NETDEV_EVENT"; 1608 } 1609 EXPORT_SYMBOL_GPL(netdev_cmd_to_name); 1610 1611 static int call_netdevice_notifier(struct notifier_block *nb, unsigned long val, 1612 struct net_device *dev) 1613 { 1614 struct netdev_notifier_info info = { 1615 .dev = dev, 1616 }; 1617 1618 return nb->notifier_call(nb, val, &info); 1619 } 1620 1621 static int call_netdevice_register_notifiers(struct notifier_block *nb, 1622 struct net_device *dev) 1623 { 1624 int err; 1625 1626 err = call_netdevice_notifier(nb, NETDEV_REGISTER, dev); 1627 err = notifier_to_errno(err); 1628 if (err) 1629 return err; 1630 1631 if (!(dev->flags & IFF_UP)) 1632 return 0; 1633 1634 call_netdevice_notifier(nb, NETDEV_UP, dev); 1635 return 0; 1636 } 1637 1638 static void call_netdevice_unregister_notifiers(struct notifier_block *nb, 1639 struct net_device *dev) 1640 { 1641 if (dev->flags & IFF_UP) { 1642 call_netdevice_notifier(nb, NETDEV_GOING_DOWN, 1643 dev); 1644 call_netdevice_notifier(nb, NETDEV_DOWN, dev); 1645 } 1646 call_netdevice_notifier(nb, NETDEV_UNREGISTER, dev); 1647 } 1648 1649 static int call_netdevice_register_net_notifiers(struct notifier_block *nb, 1650 struct net *net) 1651 { 1652 struct net_device *dev; 1653 int err; 1654 1655 for_each_netdev(net, dev) { 1656 err = call_netdevice_register_notifiers(nb, dev); 1657 if (err) 1658 goto rollback; 1659 } 1660 return 0; 1661 1662 rollback: 1663 for_each_netdev_continue_reverse(net, dev) 1664 call_netdevice_unregister_notifiers(nb, dev); 1665 return err; 1666 } 1667 1668 static void call_netdevice_unregister_net_notifiers(struct notifier_block *nb, 1669 struct net *net) 1670 { 1671 struct net_device *dev; 1672 1673 for_each_netdev(net, dev) 1674 call_netdevice_unregister_notifiers(nb, dev); 1675 } 1676 1677 static int dev_boot_phase = 1; 1678 1679 /** 1680 * register_netdevice_notifier - register a network notifier block 1681 * @nb: notifier 1682 * 1683 * Register a notifier to be called when network device events occur. 1684 * The notifier passed is linked into the kernel structures and must 1685 * not be reused until it has been unregistered. A negative errno code 1686 * is returned on a failure. 1687 * 1688 * When registered all registration and up events are replayed 1689 * to the new notifier to allow device to have a race free 1690 * view of the network device list. 1691 */ 1692 1693 int register_netdevice_notifier(struct notifier_block *nb) 1694 { 1695 struct net *net; 1696 int err; 1697 1698 /* Close race with setup_net() and cleanup_net() */ 1699 down_write(&pernet_ops_rwsem); 1700 rtnl_lock(); 1701 err = raw_notifier_chain_register(&netdev_chain, nb); 1702 if (err) 1703 goto unlock; 1704 if (dev_boot_phase) 1705 goto unlock; 1706 for_each_net(net) { 1707 err = call_netdevice_register_net_notifiers(nb, net); 1708 if (err) 1709 goto rollback; 1710 } 1711 1712 unlock: 1713 rtnl_unlock(); 1714 up_write(&pernet_ops_rwsem); 1715 return err; 1716 1717 rollback: 1718 for_each_net_continue_reverse(net) 1719 call_netdevice_unregister_net_notifiers(nb, net); 1720 1721 raw_notifier_chain_unregister(&netdev_chain, nb); 1722 goto unlock; 1723 } 1724 EXPORT_SYMBOL(register_netdevice_notifier); 1725 1726 /** 1727 * unregister_netdevice_notifier - unregister a network notifier block 1728 * @nb: notifier 1729 * 1730 * Unregister a notifier previously registered by 1731 * register_netdevice_notifier(). The notifier is unlinked into the 1732 * kernel structures and may then be reused. A negative errno code 1733 * is returned on a failure. 1734 * 1735 * After unregistering unregister and down device events are synthesized 1736 * for all devices on the device list to the removed notifier to remove 1737 * the need for special case cleanup code. 1738 */ 1739 1740 int unregister_netdevice_notifier(struct notifier_block *nb) 1741 { 1742 struct net *net; 1743 int err; 1744 1745 /* Close race with setup_net() and cleanup_net() */ 1746 down_write(&pernet_ops_rwsem); 1747 rtnl_lock(); 1748 err = raw_notifier_chain_unregister(&netdev_chain, nb); 1749 if (err) 1750 goto unlock; 1751 1752 for_each_net(net) 1753 call_netdevice_unregister_net_notifiers(nb, net); 1754 1755 unlock: 1756 rtnl_unlock(); 1757 up_write(&pernet_ops_rwsem); 1758 return err; 1759 } 1760 EXPORT_SYMBOL(unregister_netdevice_notifier); 1761 1762 static int __register_netdevice_notifier_net(struct net *net, 1763 struct notifier_block *nb, 1764 bool ignore_call_fail) 1765 { 1766 int err; 1767 1768 err = raw_notifier_chain_register(&net->netdev_chain, nb); 1769 if (err) 1770 return err; 1771 if (dev_boot_phase) 1772 return 0; 1773 1774 err = call_netdevice_register_net_notifiers(nb, net); 1775 if (err && !ignore_call_fail) 1776 goto chain_unregister; 1777 1778 return 0; 1779 1780 chain_unregister: 1781 raw_notifier_chain_unregister(&net->netdev_chain, nb); 1782 return err; 1783 } 1784 1785 static int __unregister_netdevice_notifier_net(struct net *net, 1786 struct notifier_block *nb) 1787 { 1788 int err; 1789 1790 err = raw_notifier_chain_unregister(&net->netdev_chain, nb); 1791 if (err) 1792 return err; 1793 1794 call_netdevice_unregister_net_notifiers(nb, net); 1795 return 0; 1796 } 1797 1798 /** 1799 * register_netdevice_notifier_net - register a per-netns network notifier block 1800 * @net: network namespace 1801 * @nb: notifier 1802 * 1803 * Register a notifier to be called when network device events occur. 1804 * The notifier passed is linked into the kernel structures and must 1805 * not be reused until it has been unregistered. A negative errno code 1806 * is returned on a failure. 1807 * 1808 * When registered all registration and up events are replayed 1809 * to the new notifier to allow device to have a race free 1810 * view of the network device list. 1811 */ 1812 1813 int register_netdevice_notifier_net(struct net *net, struct notifier_block *nb) 1814 { 1815 int err; 1816 1817 rtnl_lock(); 1818 err = __register_netdevice_notifier_net(net, nb, false); 1819 rtnl_unlock(); 1820 return err; 1821 } 1822 EXPORT_SYMBOL(register_netdevice_notifier_net); 1823 1824 /** 1825 * unregister_netdevice_notifier_net - unregister a per-netns 1826 * network notifier block 1827 * @net: network namespace 1828 * @nb: notifier 1829 * 1830 * Unregister a notifier previously registered by 1831 * register_netdevice_notifier(). The notifier is unlinked into the 1832 * kernel structures and may then be reused. A negative errno code 1833 * is returned on a failure. 1834 * 1835 * After unregistering unregister and down device events are synthesized 1836 * for all devices on the device list to the removed notifier to remove 1837 * the need for special case cleanup code. 1838 */ 1839 1840 int unregister_netdevice_notifier_net(struct net *net, 1841 struct notifier_block *nb) 1842 { 1843 int err; 1844 1845 rtnl_lock(); 1846 err = __unregister_netdevice_notifier_net(net, nb); 1847 rtnl_unlock(); 1848 return err; 1849 } 1850 EXPORT_SYMBOL(unregister_netdevice_notifier_net); 1851 1852 int register_netdevice_notifier_dev_net(struct net_device *dev, 1853 struct notifier_block *nb, 1854 struct netdev_net_notifier *nn) 1855 { 1856 int err; 1857 1858 rtnl_lock(); 1859 err = __register_netdevice_notifier_net(dev_net(dev), nb, false); 1860 if (!err) { 1861 nn->nb = nb; 1862 list_add(&nn->list, &dev->net_notifier_list); 1863 } 1864 rtnl_unlock(); 1865 return err; 1866 } 1867 EXPORT_SYMBOL(register_netdevice_notifier_dev_net); 1868 1869 int unregister_netdevice_notifier_dev_net(struct net_device *dev, 1870 struct notifier_block *nb, 1871 struct netdev_net_notifier *nn) 1872 { 1873 int err; 1874 1875 rtnl_lock(); 1876 list_del(&nn->list); 1877 err = __unregister_netdevice_notifier_net(dev_net(dev), nb); 1878 rtnl_unlock(); 1879 return err; 1880 } 1881 EXPORT_SYMBOL(unregister_netdevice_notifier_dev_net); 1882 1883 static void move_netdevice_notifiers_dev_net(struct net_device *dev, 1884 struct net *net) 1885 { 1886 struct netdev_net_notifier *nn; 1887 1888 list_for_each_entry(nn, &dev->net_notifier_list, list) { 1889 __unregister_netdevice_notifier_net(dev_net(dev), nn->nb); 1890 __register_netdevice_notifier_net(net, nn->nb, true); 1891 } 1892 } 1893 1894 /** 1895 * call_netdevice_notifiers_info - call all network notifier blocks 1896 * @val: value passed unmodified to notifier function 1897 * @info: notifier information data 1898 * 1899 * Call all network notifier blocks. Parameters and return value 1900 * are as for raw_notifier_call_chain(). 1901 */ 1902 1903 static int call_netdevice_notifiers_info(unsigned long val, 1904 struct netdev_notifier_info *info) 1905 { 1906 struct net *net = dev_net(info->dev); 1907 int ret; 1908 1909 ASSERT_RTNL(); 1910 1911 /* Run per-netns notifier block chain first, then run the global one. 1912 * Hopefully, one day, the global one is going to be removed after 1913 * all notifier block registrators get converted to be per-netns. 1914 */ 1915 ret = raw_notifier_call_chain(&net->netdev_chain, val, info); 1916 if (ret & NOTIFY_STOP_MASK) 1917 return ret; 1918 return raw_notifier_call_chain(&netdev_chain, val, info); 1919 } 1920 1921 static int call_netdevice_notifiers_extack(unsigned long val, 1922 struct net_device *dev, 1923 struct netlink_ext_ack *extack) 1924 { 1925 struct netdev_notifier_info info = { 1926 .dev = dev, 1927 .extack = extack, 1928 }; 1929 1930 return call_netdevice_notifiers_info(val, &info); 1931 } 1932 1933 /** 1934 * call_netdevice_notifiers - call all network notifier blocks 1935 * @val: value passed unmodified to notifier function 1936 * @dev: net_device pointer passed unmodified to notifier function 1937 * 1938 * Call all network notifier blocks. Parameters and return value 1939 * are as for raw_notifier_call_chain(). 1940 */ 1941 1942 int call_netdevice_notifiers(unsigned long val, struct net_device *dev) 1943 { 1944 return call_netdevice_notifiers_extack(val, dev, NULL); 1945 } 1946 EXPORT_SYMBOL(call_netdevice_notifiers); 1947 1948 /** 1949 * call_netdevice_notifiers_mtu - call all network notifier blocks 1950 * @val: value passed unmodified to notifier function 1951 * @dev: net_device pointer passed unmodified to notifier function 1952 * @arg: additional u32 argument passed to the notifier function 1953 * 1954 * Call all network notifier blocks. Parameters and return value 1955 * are as for raw_notifier_call_chain(). 1956 */ 1957 static int call_netdevice_notifiers_mtu(unsigned long val, 1958 struct net_device *dev, u32 arg) 1959 { 1960 struct netdev_notifier_info_ext info = { 1961 .info.dev = dev, 1962 .ext.mtu = arg, 1963 }; 1964 1965 BUILD_BUG_ON(offsetof(struct netdev_notifier_info_ext, info) != 0); 1966 1967 return call_netdevice_notifiers_info(val, &info.info); 1968 } 1969 1970 #ifdef CONFIG_NET_INGRESS 1971 static DEFINE_STATIC_KEY_FALSE(ingress_needed_key); 1972 1973 void net_inc_ingress_queue(void) 1974 { 1975 static_branch_inc(&ingress_needed_key); 1976 } 1977 EXPORT_SYMBOL_GPL(net_inc_ingress_queue); 1978 1979 void net_dec_ingress_queue(void) 1980 { 1981 static_branch_dec(&ingress_needed_key); 1982 } 1983 EXPORT_SYMBOL_GPL(net_dec_ingress_queue); 1984 #endif 1985 1986 #ifdef CONFIG_NET_EGRESS 1987 static DEFINE_STATIC_KEY_FALSE(egress_needed_key); 1988 1989 void net_inc_egress_queue(void) 1990 { 1991 static_branch_inc(&egress_needed_key); 1992 } 1993 EXPORT_SYMBOL_GPL(net_inc_egress_queue); 1994 1995 void net_dec_egress_queue(void) 1996 { 1997 static_branch_dec(&egress_needed_key); 1998 } 1999 EXPORT_SYMBOL_GPL(net_dec_egress_queue); 2000 #endif 2001 2002 static DEFINE_STATIC_KEY_FALSE(netstamp_needed_key); 2003 #ifdef CONFIG_JUMP_LABEL 2004 static atomic_t netstamp_needed_deferred; 2005 static atomic_t netstamp_wanted; 2006 static void netstamp_clear(struct work_struct *work) 2007 { 2008 int deferred = atomic_xchg(&netstamp_needed_deferred, 0); 2009 int wanted; 2010 2011 wanted = atomic_add_return(deferred, &netstamp_wanted); 2012 if (wanted > 0) 2013 static_branch_enable(&netstamp_needed_key); 2014 else 2015 static_branch_disable(&netstamp_needed_key); 2016 } 2017 static DECLARE_WORK(netstamp_work, netstamp_clear); 2018 #endif 2019 2020 void net_enable_timestamp(void) 2021 { 2022 #ifdef CONFIG_JUMP_LABEL 2023 int wanted; 2024 2025 while (1) { 2026 wanted = atomic_read(&netstamp_wanted); 2027 if (wanted <= 0) 2028 break; 2029 if (atomic_cmpxchg(&netstamp_wanted, wanted, wanted + 1) == wanted) 2030 return; 2031 } 2032 atomic_inc(&netstamp_needed_deferred); 2033 schedule_work(&netstamp_work); 2034 #else 2035 static_branch_inc(&netstamp_needed_key); 2036 #endif 2037 } 2038 EXPORT_SYMBOL(net_enable_timestamp); 2039 2040 void net_disable_timestamp(void) 2041 { 2042 #ifdef CONFIG_JUMP_LABEL 2043 int wanted; 2044 2045 while (1) { 2046 wanted = atomic_read(&netstamp_wanted); 2047 if (wanted <= 1) 2048 break; 2049 if (atomic_cmpxchg(&netstamp_wanted, wanted, wanted - 1) == wanted) 2050 return; 2051 } 2052 atomic_dec(&netstamp_needed_deferred); 2053 schedule_work(&netstamp_work); 2054 #else 2055 static_branch_dec(&netstamp_needed_key); 2056 #endif 2057 } 2058 EXPORT_SYMBOL(net_disable_timestamp); 2059 2060 static inline void net_timestamp_set(struct sk_buff *skb) 2061 { 2062 skb->tstamp = 0; 2063 if (static_branch_unlikely(&netstamp_needed_key)) 2064 __net_timestamp(skb); 2065 } 2066 2067 #define net_timestamp_check(COND, SKB) \ 2068 if (static_branch_unlikely(&netstamp_needed_key)) { \ 2069 if ((COND) && !(SKB)->tstamp) \ 2070 __net_timestamp(SKB); \ 2071 } \ 2072 2073 bool is_skb_forwardable(const struct net_device *dev, const struct sk_buff *skb) 2074 { 2075 return __is_skb_forwardable(dev, skb, true); 2076 } 2077 EXPORT_SYMBOL_GPL(is_skb_forwardable); 2078 2079 static int __dev_forward_skb2(struct net_device *dev, struct sk_buff *skb, 2080 bool check_mtu) 2081 { 2082 int ret = ____dev_forward_skb(dev, skb, check_mtu); 2083 2084 if (likely(!ret)) { 2085 skb->protocol = eth_type_trans(skb, dev); 2086 skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN); 2087 } 2088 2089 return ret; 2090 } 2091 2092 int __dev_forward_skb(struct net_device *dev, struct sk_buff *skb) 2093 { 2094 return __dev_forward_skb2(dev, skb, true); 2095 } 2096 EXPORT_SYMBOL_GPL(__dev_forward_skb); 2097 2098 /** 2099 * dev_forward_skb - loopback an skb to another netif 2100 * 2101 * @dev: destination network device 2102 * @skb: buffer to forward 2103 * 2104 * return values: 2105 * NET_RX_SUCCESS (no congestion) 2106 * NET_RX_DROP (packet was dropped, but freed) 2107 * 2108 * dev_forward_skb can be used for injecting an skb from the 2109 * start_xmit function of one device into the receive queue 2110 * of another device. 2111 * 2112 * The receiving device may be in another namespace, so 2113 * we have to clear all information in the skb that could 2114 * impact namespace isolation. 2115 */ 2116 int dev_forward_skb(struct net_device *dev, struct sk_buff *skb) 2117 { 2118 return __dev_forward_skb(dev, skb) ?: netif_rx_internal(skb); 2119 } 2120 EXPORT_SYMBOL_GPL(dev_forward_skb); 2121 2122 int dev_forward_skb_nomtu(struct net_device *dev, struct sk_buff *skb) 2123 { 2124 return __dev_forward_skb2(dev, skb, false) ?: netif_rx_internal(skb); 2125 } 2126 2127 static inline int deliver_skb(struct sk_buff *skb, 2128 struct packet_type *pt_prev, 2129 struct net_device *orig_dev) 2130 { 2131 if (unlikely(skb_orphan_frags_rx(skb, GFP_ATOMIC))) 2132 return -ENOMEM; 2133 refcount_inc(&skb->users); 2134 return pt_prev->func(skb, skb->dev, pt_prev, orig_dev); 2135 } 2136 2137 static inline void deliver_ptype_list_skb(struct sk_buff *skb, 2138 struct packet_type **pt, 2139 struct net_device *orig_dev, 2140 __be16 type, 2141 struct list_head *ptype_list) 2142 { 2143 struct packet_type *ptype, *pt_prev = *pt; 2144 2145 list_for_each_entry_rcu(ptype, ptype_list, list) { 2146 if (ptype->type != type) 2147 continue; 2148 if (pt_prev) 2149 deliver_skb(skb, pt_prev, orig_dev); 2150 pt_prev = ptype; 2151 } 2152 *pt = pt_prev; 2153 } 2154 2155 static inline bool skb_loop_sk(struct packet_type *ptype, struct sk_buff *skb) 2156 { 2157 if (!ptype->af_packet_priv || !skb->sk) 2158 return false; 2159 2160 if (ptype->id_match) 2161 return ptype->id_match(ptype, skb->sk); 2162 else if ((struct sock *)ptype->af_packet_priv == skb->sk) 2163 return true; 2164 2165 return false; 2166 } 2167 2168 /** 2169 * dev_nit_active - return true if any network interface taps are in use 2170 * 2171 * @dev: network device to check for the presence of taps 2172 */ 2173 bool dev_nit_active(struct net_device *dev) 2174 { 2175 return !list_empty(&ptype_all) || !list_empty(&dev->ptype_all); 2176 } 2177 EXPORT_SYMBOL_GPL(dev_nit_active); 2178 2179 /* 2180 * Support routine. Sends outgoing frames to any network 2181 * taps currently in use. 2182 */ 2183 2184 void dev_queue_xmit_nit(struct sk_buff *skb, struct net_device *dev) 2185 { 2186 struct packet_type *ptype; 2187 struct sk_buff *skb2 = NULL; 2188 struct packet_type *pt_prev = NULL; 2189 struct list_head *ptype_list = &ptype_all; 2190 2191 rcu_read_lock(); 2192 again: 2193 list_for_each_entry_rcu(ptype, ptype_list, list) { 2194 if (ptype->ignore_outgoing) 2195 continue; 2196 2197 /* Never send packets back to the socket 2198 * they originated from - MvS (miquels@drinkel.ow.org) 2199 */ 2200 if (skb_loop_sk(ptype, skb)) 2201 continue; 2202 2203 if (pt_prev) { 2204 deliver_skb(skb2, pt_prev, skb->dev); 2205 pt_prev = ptype; 2206 continue; 2207 } 2208 2209 /* need to clone skb, done only once */ 2210 skb2 = skb_clone(skb, GFP_ATOMIC); 2211 if (!skb2) 2212 goto out_unlock; 2213 2214 net_timestamp_set(skb2); 2215 2216 /* skb->nh should be correctly 2217 * set by sender, so that the second statement is 2218 * just protection against buggy protocols. 2219 */ 2220 skb_reset_mac_header(skb2); 2221 2222 if (skb_network_header(skb2) < skb2->data || 2223 skb_network_header(skb2) > skb_tail_pointer(skb2)) { 2224 net_crit_ratelimited("protocol %04x is buggy, dev %s\n", 2225 ntohs(skb2->protocol), 2226 dev->name); 2227 skb_reset_network_header(skb2); 2228 } 2229 2230 skb2->transport_header = skb2->network_header; 2231 skb2->pkt_type = PACKET_OUTGOING; 2232 pt_prev = ptype; 2233 } 2234 2235 if (ptype_list == &ptype_all) { 2236 ptype_list = &dev->ptype_all; 2237 goto again; 2238 } 2239 out_unlock: 2240 if (pt_prev) { 2241 if (!skb_orphan_frags_rx(skb2, GFP_ATOMIC)) 2242 pt_prev->func(skb2, skb->dev, pt_prev, skb->dev); 2243 else 2244 kfree_skb(skb2); 2245 } 2246 rcu_read_unlock(); 2247 } 2248 EXPORT_SYMBOL_GPL(dev_queue_xmit_nit); 2249 2250 /** 2251 * netif_setup_tc - Handle tc mappings on real_num_tx_queues change 2252 * @dev: Network device 2253 * @txq: number of queues available 2254 * 2255 * If real_num_tx_queues is changed the tc mappings may no longer be 2256 * valid. To resolve this verify the tc mapping remains valid and if 2257 * not NULL the mapping. With no priorities mapping to this 2258 * offset/count pair it will no longer be used. In the worst case TC0 2259 * is invalid nothing can be done so disable priority mappings. If is 2260 * expected that drivers will fix this mapping if they can before 2261 * calling netif_set_real_num_tx_queues. 2262 */ 2263 static void netif_setup_tc(struct net_device *dev, unsigned int txq) 2264 { 2265 int i; 2266 struct netdev_tc_txq *tc = &dev->tc_to_txq[0]; 2267 2268 /* If TC0 is invalidated disable TC mapping */ 2269 if (tc->offset + tc->count > txq) { 2270 netdev_warn(dev, "Number of in use tx queues changed invalidating tc mappings. Priority traffic classification disabled!\n"); 2271 dev->num_tc = 0; 2272 return; 2273 } 2274 2275 /* Invalidated prio to tc mappings set to TC0 */ 2276 for (i = 1; i < TC_BITMASK + 1; i++) { 2277 int q = netdev_get_prio_tc_map(dev, i); 2278 2279 tc = &dev->tc_to_txq[q]; 2280 if (tc->offset + tc->count > txq) { 2281 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", 2282 i, q); 2283 netdev_set_prio_tc_map(dev, i, 0); 2284 } 2285 } 2286 } 2287 2288 int netdev_txq_to_tc(struct net_device *dev, unsigned int txq) 2289 { 2290 if (dev->num_tc) { 2291 struct netdev_tc_txq *tc = &dev->tc_to_txq[0]; 2292 int i; 2293 2294 /* walk through the TCs and see if it falls into any of them */ 2295 for (i = 0; i < TC_MAX_QUEUE; i++, tc++) { 2296 if ((txq - tc->offset) < tc->count) 2297 return i; 2298 } 2299 2300 /* didn't find it, just return -1 to indicate no match */ 2301 return -1; 2302 } 2303 2304 return 0; 2305 } 2306 EXPORT_SYMBOL(netdev_txq_to_tc); 2307 2308 #ifdef CONFIG_XPS 2309 static struct static_key xps_needed __read_mostly; 2310 static struct static_key xps_rxqs_needed __read_mostly; 2311 static DEFINE_MUTEX(xps_map_mutex); 2312 #define xmap_dereference(P) \ 2313 rcu_dereference_protected((P), lockdep_is_held(&xps_map_mutex)) 2314 2315 static bool remove_xps_queue(struct xps_dev_maps *dev_maps, 2316 struct xps_dev_maps *old_maps, int tci, u16 index) 2317 { 2318 struct xps_map *map = NULL; 2319 int pos; 2320 2321 if (dev_maps) 2322 map = xmap_dereference(dev_maps->attr_map[tci]); 2323 if (!map) 2324 return false; 2325 2326 for (pos = map->len; pos--;) { 2327 if (map->queues[pos] != index) 2328 continue; 2329 2330 if (map->len > 1) { 2331 map->queues[pos] = map->queues[--map->len]; 2332 break; 2333 } 2334 2335 if (old_maps) 2336 RCU_INIT_POINTER(old_maps->attr_map[tci], NULL); 2337 RCU_INIT_POINTER(dev_maps->attr_map[tci], NULL); 2338 kfree_rcu(map, rcu); 2339 return false; 2340 } 2341 2342 return true; 2343 } 2344 2345 static bool remove_xps_queue_cpu(struct net_device *dev, 2346 struct xps_dev_maps *dev_maps, 2347 int cpu, u16 offset, u16 count) 2348 { 2349 int num_tc = dev_maps->num_tc; 2350 bool active = false; 2351 int tci; 2352 2353 for (tci = cpu * num_tc; num_tc--; tci++) { 2354 int i, j; 2355 2356 for (i = count, j = offset; i--; j++) { 2357 if (!remove_xps_queue(dev_maps, NULL, tci, j)) 2358 break; 2359 } 2360 2361 active |= i < 0; 2362 } 2363 2364 return active; 2365 } 2366 2367 static void reset_xps_maps(struct net_device *dev, 2368 struct xps_dev_maps *dev_maps, 2369 enum xps_map_type type) 2370 { 2371 static_key_slow_dec_cpuslocked(&xps_needed); 2372 if (type == XPS_RXQS) 2373 static_key_slow_dec_cpuslocked(&xps_rxqs_needed); 2374 2375 RCU_INIT_POINTER(dev->xps_maps[type], NULL); 2376 2377 kfree_rcu(dev_maps, rcu); 2378 } 2379 2380 static void clean_xps_maps(struct net_device *dev, enum xps_map_type type, 2381 u16 offset, u16 count) 2382 { 2383 struct xps_dev_maps *dev_maps; 2384 bool active = false; 2385 int i, j; 2386 2387 dev_maps = xmap_dereference(dev->xps_maps[type]); 2388 if (!dev_maps) 2389 return; 2390 2391 for (j = 0; j < dev_maps->nr_ids; j++) 2392 active |= remove_xps_queue_cpu(dev, dev_maps, j, offset, count); 2393 if (!active) 2394 reset_xps_maps(dev, dev_maps, type); 2395 2396 if (type == XPS_CPUS) { 2397 for (i = offset + (count - 1); count--; i--) 2398 netdev_queue_numa_node_write( 2399 netdev_get_tx_queue(dev, i), NUMA_NO_NODE); 2400 } 2401 } 2402 2403 static void netif_reset_xps_queues(struct net_device *dev, u16 offset, 2404 u16 count) 2405 { 2406 if (!static_key_false(&xps_needed)) 2407 return; 2408 2409 cpus_read_lock(); 2410 mutex_lock(&xps_map_mutex); 2411 2412 if (static_key_false(&xps_rxqs_needed)) 2413 clean_xps_maps(dev, XPS_RXQS, offset, count); 2414 2415 clean_xps_maps(dev, XPS_CPUS, offset, count); 2416 2417 mutex_unlock(&xps_map_mutex); 2418 cpus_read_unlock(); 2419 } 2420 2421 static void netif_reset_xps_queues_gt(struct net_device *dev, u16 index) 2422 { 2423 netif_reset_xps_queues(dev, index, dev->num_tx_queues - index); 2424 } 2425 2426 static struct xps_map *expand_xps_map(struct xps_map *map, int attr_index, 2427 u16 index, bool is_rxqs_map) 2428 { 2429 struct xps_map *new_map; 2430 int alloc_len = XPS_MIN_MAP_ALLOC; 2431 int i, pos; 2432 2433 for (pos = 0; map && pos < map->len; pos++) { 2434 if (map->queues[pos] != index) 2435 continue; 2436 return map; 2437 } 2438 2439 /* Need to add tx-queue to this CPU's/rx-queue's existing map */ 2440 if (map) { 2441 if (pos < map->alloc_len) 2442 return map; 2443 2444 alloc_len = map->alloc_len * 2; 2445 } 2446 2447 /* Need to allocate new map to store tx-queue on this CPU's/rx-queue's 2448 * map 2449 */ 2450 if (is_rxqs_map) 2451 new_map = kzalloc(XPS_MAP_SIZE(alloc_len), GFP_KERNEL); 2452 else 2453 new_map = kzalloc_node(XPS_MAP_SIZE(alloc_len), GFP_KERNEL, 2454 cpu_to_node(attr_index)); 2455 if (!new_map) 2456 return NULL; 2457 2458 for (i = 0; i < pos; i++) 2459 new_map->queues[i] = map->queues[i]; 2460 new_map->alloc_len = alloc_len; 2461 new_map->len = pos; 2462 2463 return new_map; 2464 } 2465 2466 /* Copy xps maps at a given index */ 2467 static void xps_copy_dev_maps(struct xps_dev_maps *dev_maps, 2468 struct xps_dev_maps *new_dev_maps, int index, 2469 int tc, bool skip_tc) 2470 { 2471 int i, tci = index * dev_maps->num_tc; 2472 struct xps_map *map; 2473 2474 /* copy maps belonging to foreign traffic classes */ 2475 for (i = 0; i < dev_maps->num_tc; i++, tci++) { 2476 if (i == tc && skip_tc) 2477 continue; 2478 2479 /* fill in the new device map from the old device map */ 2480 map = xmap_dereference(dev_maps->attr_map[tci]); 2481 RCU_INIT_POINTER(new_dev_maps->attr_map[tci], map); 2482 } 2483 } 2484 2485 /* Must be called under cpus_read_lock */ 2486 int __netif_set_xps_queue(struct net_device *dev, const unsigned long *mask, 2487 u16 index, enum xps_map_type type) 2488 { 2489 struct xps_dev_maps *dev_maps, *new_dev_maps = NULL, *old_dev_maps = NULL; 2490 const unsigned long *online_mask = NULL; 2491 bool active = false, copy = false; 2492 int i, j, tci, numa_node_id = -2; 2493 int maps_sz, num_tc = 1, tc = 0; 2494 struct xps_map *map, *new_map; 2495 unsigned int nr_ids; 2496 2497 if (dev->num_tc) { 2498 /* Do not allow XPS on subordinate device directly */ 2499 num_tc = dev->num_tc; 2500 if (num_tc < 0) 2501 return -EINVAL; 2502 2503 /* If queue belongs to subordinate dev use its map */ 2504 dev = netdev_get_tx_queue(dev, index)->sb_dev ? : dev; 2505 2506 tc = netdev_txq_to_tc(dev, index); 2507 if (tc < 0) 2508 return -EINVAL; 2509 } 2510 2511 mutex_lock(&xps_map_mutex); 2512 2513 dev_maps = xmap_dereference(dev->xps_maps[type]); 2514 if (type == XPS_RXQS) { 2515 maps_sz = XPS_RXQ_DEV_MAPS_SIZE(num_tc, dev->num_rx_queues); 2516 nr_ids = dev->num_rx_queues; 2517 } else { 2518 maps_sz = XPS_CPU_DEV_MAPS_SIZE(num_tc); 2519 if (num_possible_cpus() > 1) 2520 online_mask = cpumask_bits(cpu_online_mask); 2521 nr_ids = nr_cpu_ids; 2522 } 2523 2524 if (maps_sz < L1_CACHE_BYTES) 2525 maps_sz = L1_CACHE_BYTES; 2526 2527 /* The old dev_maps could be larger or smaller than the one we're 2528 * setting up now, as dev->num_tc or nr_ids could have been updated in 2529 * between. We could try to be smart, but let's be safe instead and only 2530 * copy foreign traffic classes if the two map sizes match. 2531 */ 2532 if (dev_maps && 2533 dev_maps->num_tc == num_tc && dev_maps->nr_ids == nr_ids) 2534 copy = true; 2535 2536 /* allocate memory for queue storage */ 2537 for (j = -1; j = netif_attrmask_next_and(j, online_mask, mask, nr_ids), 2538 j < nr_ids;) { 2539 if (!new_dev_maps) { 2540 new_dev_maps = kzalloc(maps_sz, GFP_KERNEL); 2541 if (!new_dev_maps) { 2542 mutex_unlock(&xps_map_mutex); 2543 return -ENOMEM; 2544 } 2545 2546 new_dev_maps->nr_ids = nr_ids; 2547 new_dev_maps->num_tc = num_tc; 2548 } 2549 2550 tci = j * num_tc + tc; 2551 map = copy ? xmap_dereference(dev_maps->attr_map[tci]) : NULL; 2552 2553 map = expand_xps_map(map, j, index, type == XPS_RXQS); 2554 if (!map) 2555 goto error; 2556 2557 RCU_INIT_POINTER(new_dev_maps->attr_map[tci], map); 2558 } 2559 2560 if (!new_dev_maps) 2561 goto out_no_new_maps; 2562 2563 if (!dev_maps) { 2564 /* Increment static keys at most once per type */ 2565 static_key_slow_inc_cpuslocked(&xps_needed); 2566 if (type == XPS_RXQS) 2567 static_key_slow_inc_cpuslocked(&xps_rxqs_needed); 2568 } 2569 2570 for (j = 0; j < nr_ids; j++) { 2571 bool skip_tc = false; 2572 2573 tci = j * num_tc + tc; 2574 if (netif_attr_test_mask(j, mask, nr_ids) && 2575 netif_attr_test_online(j, online_mask, nr_ids)) { 2576 /* add tx-queue to CPU/rx-queue maps */ 2577 int pos = 0; 2578 2579 skip_tc = true; 2580 2581 map = xmap_dereference(new_dev_maps->attr_map[tci]); 2582 while ((pos < map->len) && (map->queues[pos] != index)) 2583 pos++; 2584 2585 if (pos == map->len) 2586 map->queues[map->len++] = index; 2587 #ifdef CONFIG_NUMA 2588 if (type == XPS_CPUS) { 2589 if (numa_node_id == -2) 2590 numa_node_id = cpu_to_node(j); 2591 else if (numa_node_id != cpu_to_node(j)) 2592 numa_node_id = -1; 2593 } 2594 #endif 2595 } 2596 2597 if (copy) 2598 xps_copy_dev_maps(dev_maps, new_dev_maps, j, tc, 2599 skip_tc); 2600 } 2601 2602 rcu_assign_pointer(dev->xps_maps[type], new_dev_maps); 2603 2604 /* Cleanup old maps */ 2605 if (!dev_maps) 2606 goto out_no_old_maps; 2607 2608 for (j = 0; j < dev_maps->nr_ids; j++) { 2609 for (i = num_tc, tci = j * dev_maps->num_tc; i--; tci++) { 2610 map = xmap_dereference(dev_maps->attr_map[tci]); 2611 if (!map) 2612 continue; 2613 2614 if (copy) { 2615 new_map = xmap_dereference(new_dev_maps->attr_map[tci]); 2616 if (map == new_map) 2617 continue; 2618 } 2619 2620 RCU_INIT_POINTER(dev_maps->attr_map[tci], NULL); 2621 kfree_rcu(map, rcu); 2622 } 2623 } 2624 2625 old_dev_maps = dev_maps; 2626 2627 out_no_old_maps: 2628 dev_maps = new_dev_maps; 2629 active = true; 2630 2631 out_no_new_maps: 2632 if (type == XPS_CPUS) 2633 /* update Tx queue numa node */ 2634 netdev_queue_numa_node_write(netdev_get_tx_queue(dev, index), 2635 (numa_node_id >= 0) ? 2636 numa_node_id : NUMA_NO_NODE); 2637 2638 if (!dev_maps) 2639 goto out_no_maps; 2640 2641 /* removes tx-queue from unused CPUs/rx-queues */ 2642 for (j = 0; j < dev_maps->nr_ids; j++) { 2643 tci = j * dev_maps->num_tc; 2644 2645 for (i = 0; i < dev_maps->num_tc; i++, tci++) { 2646 if (i == tc && 2647 netif_attr_test_mask(j, mask, dev_maps->nr_ids) && 2648 netif_attr_test_online(j, online_mask, dev_maps->nr_ids)) 2649 continue; 2650 2651 active |= remove_xps_queue(dev_maps, 2652 copy ? old_dev_maps : NULL, 2653 tci, index); 2654 } 2655 } 2656 2657 if (old_dev_maps) 2658 kfree_rcu(old_dev_maps, rcu); 2659 2660 /* free map if not active */ 2661 if (!active) 2662 reset_xps_maps(dev, dev_maps, type); 2663 2664 out_no_maps: 2665 mutex_unlock(&xps_map_mutex); 2666 2667 return 0; 2668 error: 2669 /* remove any maps that we added */ 2670 for (j = 0; j < nr_ids; j++) { 2671 for (i = num_tc, tci = j * num_tc; i--; tci++) { 2672 new_map = xmap_dereference(new_dev_maps->attr_map[tci]); 2673 map = copy ? 2674 xmap_dereference(dev_maps->attr_map[tci]) : 2675 NULL; 2676 if (new_map && new_map != map) 2677 kfree(new_map); 2678 } 2679 } 2680 2681 mutex_unlock(&xps_map_mutex); 2682 2683 kfree(new_dev_maps); 2684 return -ENOMEM; 2685 } 2686 EXPORT_SYMBOL_GPL(__netif_set_xps_queue); 2687 2688 int netif_set_xps_queue(struct net_device *dev, const struct cpumask *mask, 2689 u16 index) 2690 { 2691 int ret; 2692 2693 cpus_read_lock(); 2694 ret = __netif_set_xps_queue(dev, cpumask_bits(mask), index, XPS_CPUS); 2695 cpus_read_unlock(); 2696 2697 return ret; 2698 } 2699 EXPORT_SYMBOL(netif_set_xps_queue); 2700 2701 #endif 2702 static void netdev_unbind_all_sb_channels(struct net_device *dev) 2703 { 2704 struct netdev_queue *txq = &dev->_tx[dev->num_tx_queues]; 2705 2706 /* Unbind any subordinate channels */ 2707 while (txq-- != &dev->_tx[0]) { 2708 if (txq->sb_dev) 2709 netdev_unbind_sb_channel(dev, txq->sb_dev); 2710 } 2711 } 2712 2713 void netdev_reset_tc(struct net_device *dev) 2714 { 2715 #ifdef CONFIG_XPS 2716 netif_reset_xps_queues_gt(dev, 0); 2717 #endif 2718 netdev_unbind_all_sb_channels(dev); 2719 2720 /* Reset TC configuration of device */ 2721 dev->num_tc = 0; 2722 memset(dev->tc_to_txq, 0, sizeof(dev->tc_to_txq)); 2723 memset(dev->prio_tc_map, 0, sizeof(dev->prio_tc_map)); 2724 } 2725 EXPORT_SYMBOL(netdev_reset_tc); 2726 2727 int netdev_set_tc_queue(struct net_device *dev, u8 tc, u16 count, u16 offset) 2728 { 2729 if (tc >= dev->num_tc) 2730 return -EINVAL; 2731 2732 #ifdef CONFIG_XPS 2733 netif_reset_xps_queues(dev, offset, count); 2734 #endif 2735 dev->tc_to_txq[tc].count = count; 2736 dev->tc_to_txq[tc].offset = offset; 2737 return 0; 2738 } 2739 EXPORT_SYMBOL(netdev_set_tc_queue); 2740 2741 int netdev_set_num_tc(struct net_device *dev, u8 num_tc) 2742 { 2743 if (num_tc > TC_MAX_QUEUE) 2744 return -EINVAL; 2745 2746 #ifdef CONFIG_XPS 2747 netif_reset_xps_queues_gt(dev, 0); 2748 #endif 2749 netdev_unbind_all_sb_channels(dev); 2750 2751 dev->num_tc = num_tc; 2752 return 0; 2753 } 2754 EXPORT_SYMBOL(netdev_set_num_tc); 2755 2756 void netdev_unbind_sb_channel(struct net_device *dev, 2757 struct net_device *sb_dev) 2758 { 2759 struct netdev_queue *txq = &dev->_tx[dev->num_tx_queues]; 2760 2761 #ifdef CONFIG_XPS 2762 netif_reset_xps_queues_gt(sb_dev, 0); 2763 #endif 2764 memset(sb_dev->tc_to_txq, 0, sizeof(sb_dev->tc_to_txq)); 2765 memset(sb_dev->prio_tc_map, 0, sizeof(sb_dev->prio_tc_map)); 2766 2767 while (txq-- != &dev->_tx[0]) { 2768 if (txq->sb_dev == sb_dev) 2769 txq->sb_dev = NULL; 2770 } 2771 } 2772 EXPORT_SYMBOL(netdev_unbind_sb_channel); 2773 2774 int netdev_bind_sb_channel_queue(struct net_device *dev, 2775 struct net_device *sb_dev, 2776 u8 tc, u16 count, u16 offset) 2777 { 2778 /* Make certain the sb_dev and dev are already configured */ 2779 if (sb_dev->num_tc >= 0 || tc >= dev->num_tc) 2780 return -EINVAL; 2781 2782 /* We cannot hand out queues we don't have */ 2783 if ((offset + count) > dev->real_num_tx_queues) 2784 return -EINVAL; 2785 2786 /* Record the mapping */ 2787 sb_dev->tc_to_txq[tc].count = count; 2788 sb_dev->tc_to_txq[tc].offset = offset; 2789 2790 /* Provide a way for Tx queue to find the tc_to_txq map or 2791 * XPS map for itself. 2792 */ 2793 while (count--) 2794 netdev_get_tx_queue(dev, count + offset)->sb_dev = sb_dev; 2795 2796 return 0; 2797 } 2798 EXPORT_SYMBOL(netdev_bind_sb_channel_queue); 2799 2800 int netdev_set_sb_channel(struct net_device *dev, u16 channel) 2801 { 2802 /* Do not use a multiqueue device to represent a subordinate channel */ 2803 if (netif_is_multiqueue(dev)) 2804 return -ENODEV; 2805 2806 /* We allow channels 1 - 32767 to be used for subordinate channels. 2807 * Channel 0 is meant to be "native" mode and used only to represent 2808 * the main root device. We allow writing 0 to reset the device back 2809 * to normal mode after being used as a subordinate channel. 2810 */ 2811 if (channel > S16_MAX) 2812 return -EINVAL; 2813 2814 dev->num_tc = -channel; 2815 2816 return 0; 2817 } 2818 EXPORT_SYMBOL(netdev_set_sb_channel); 2819 2820 /* 2821 * Routine to help set real_num_tx_queues. To avoid skbs mapped to queues 2822 * greater than real_num_tx_queues stale skbs on the qdisc must be flushed. 2823 */ 2824 int netif_set_real_num_tx_queues(struct net_device *dev, unsigned int txq) 2825 { 2826 bool disabling; 2827 int rc; 2828 2829 disabling = txq < dev->real_num_tx_queues; 2830 2831 if (txq < 1 || txq > dev->num_tx_queues) 2832 return -EINVAL; 2833 2834 if (dev->reg_state == NETREG_REGISTERED || 2835 dev->reg_state == NETREG_UNREGISTERING) { 2836 ASSERT_RTNL(); 2837 2838 rc = netdev_queue_update_kobjects(dev, dev->real_num_tx_queues, 2839 txq); 2840 if (rc) 2841 return rc; 2842 2843 if (dev->num_tc) 2844 netif_setup_tc(dev, txq); 2845 2846 dev_qdisc_change_real_num_tx(dev, txq); 2847 2848 dev->real_num_tx_queues = txq; 2849 2850 if (disabling) { 2851 synchronize_net(); 2852 qdisc_reset_all_tx_gt(dev, txq); 2853 #ifdef CONFIG_XPS 2854 netif_reset_xps_queues_gt(dev, txq); 2855 #endif 2856 } 2857 } else { 2858 dev->real_num_tx_queues = txq; 2859 } 2860 2861 return 0; 2862 } 2863 EXPORT_SYMBOL(netif_set_real_num_tx_queues); 2864 2865 #ifdef CONFIG_SYSFS 2866 /** 2867 * netif_set_real_num_rx_queues - set actual number of RX queues used 2868 * @dev: Network device 2869 * @rxq: Actual number of RX queues 2870 * 2871 * This must be called either with the rtnl_lock held or before 2872 * registration of the net device. Returns 0 on success, or a 2873 * negative error code. If called before registration, it always 2874 * succeeds. 2875 */ 2876 int netif_set_real_num_rx_queues(struct net_device *dev, unsigned int rxq) 2877 { 2878 int rc; 2879 2880 if (rxq < 1 || rxq > dev->num_rx_queues) 2881 return -EINVAL; 2882 2883 if (dev->reg_state == NETREG_REGISTERED) { 2884 ASSERT_RTNL(); 2885 2886 rc = net_rx_queue_update_kobjects(dev, dev->real_num_rx_queues, 2887 rxq); 2888 if (rc) 2889 return rc; 2890 } 2891 2892 dev->real_num_rx_queues = rxq; 2893 return 0; 2894 } 2895 EXPORT_SYMBOL(netif_set_real_num_rx_queues); 2896 #endif 2897 2898 /** 2899 * netif_set_real_num_queues - set actual number of RX and TX queues used 2900 * @dev: Network device 2901 * @txq: Actual number of TX queues 2902 * @rxq: Actual number of RX queues 2903 * 2904 * Set the real number of both TX and RX queues. 2905 * Does nothing if the number of queues is already correct. 2906 */ 2907 int netif_set_real_num_queues(struct net_device *dev, 2908 unsigned int txq, unsigned int rxq) 2909 { 2910 unsigned int old_rxq = dev->real_num_rx_queues; 2911 int err; 2912 2913 if (txq < 1 || txq > dev->num_tx_queues || 2914 rxq < 1 || rxq > dev->num_rx_queues) 2915 return -EINVAL; 2916 2917 /* Start from increases, so the error path only does decreases - 2918 * decreases can't fail. 2919 */ 2920 if (rxq > dev->real_num_rx_queues) { 2921 err = netif_set_real_num_rx_queues(dev, rxq); 2922 if (err) 2923 return err; 2924 } 2925 if (txq > dev->real_num_tx_queues) { 2926 err = netif_set_real_num_tx_queues(dev, txq); 2927 if (err) 2928 goto undo_rx; 2929 } 2930 if (rxq < dev->real_num_rx_queues) 2931 WARN_ON(netif_set_real_num_rx_queues(dev, rxq)); 2932 if (txq < dev->real_num_tx_queues) 2933 WARN_ON(netif_set_real_num_tx_queues(dev, txq)); 2934 2935 return 0; 2936 undo_rx: 2937 WARN_ON(netif_set_real_num_rx_queues(dev, old_rxq)); 2938 return err; 2939 } 2940 EXPORT_SYMBOL(netif_set_real_num_queues); 2941 2942 /** 2943 * netif_get_num_default_rss_queues - default number of RSS queues 2944 * 2945 * This routine should set an upper limit on the number of RSS queues 2946 * used by default by multiqueue devices. 2947 */ 2948 int netif_get_num_default_rss_queues(void) 2949 { 2950 return is_kdump_kernel() ? 2951 1 : min_t(int, DEFAULT_MAX_NUM_RSS_QUEUES, num_online_cpus()); 2952 } 2953 EXPORT_SYMBOL(netif_get_num_default_rss_queues); 2954 2955 static void __netif_reschedule(struct Qdisc *q) 2956 { 2957 struct softnet_data *sd; 2958 unsigned long flags; 2959 2960 local_irq_save(flags); 2961 sd = this_cpu_ptr(&softnet_data); 2962 q->next_sched = NULL; 2963 *sd->output_queue_tailp = q; 2964 sd->output_queue_tailp = &q->next_sched; 2965 raise_softirq_irqoff(NET_TX_SOFTIRQ); 2966 local_irq_restore(flags); 2967 } 2968 2969 void __netif_schedule(struct Qdisc *q) 2970 { 2971 if (!test_and_set_bit(__QDISC_STATE_SCHED, &q->state)) 2972 __netif_reschedule(q); 2973 } 2974 EXPORT_SYMBOL(__netif_schedule); 2975 2976 struct dev_kfree_skb_cb { 2977 enum skb_free_reason reason; 2978 }; 2979 2980 static struct dev_kfree_skb_cb *get_kfree_skb_cb(const struct sk_buff *skb) 2981 { 2982 return (struct dev_kfree_skb_cb *)skb->cb; 2983 } 2984 2985 void netif_schedule_queue(struct netdev_queue *txq) 2986 { 2987 rcu_read_lock(); 2988 if (!netif_xmit_stopped(txq)) { 2989 struct Qdisc *q = rcu_dereference(txq->qdisc); 2990 2991 __netif_schedule(q); 2992 } 2993 rcu_read_unlock(); 2994 } 2995 EXPORT_SYMBOL(netif_schedule_queue); 2996 2997 void netif_tx_wake_queue(struct netdev_queue *dev_queue) 2998 { 2999 if (test_and_clear_bit(__QUEUE_STATE_DRV_XOFF, &dev_queue->state)) { 3000 struct Qdisc *q; 3001 3002 rcu_read_lock(); 3003 q = rcu_dereference(dev_queue->qdisc); 3004 __netif_schedule(q); 3005 rcu_read_unlock(); 3006 } 3007 } 3008 EXPORT_SYMBOL(netif_tx_wake_queue); 3009 3010 void __dev_kfree_skb_irq(struct sk_buff *skb, enum skb_free_reason reason) 3011 { 3012 unsigned long flags; 3013 3014 if (unlikely(!skb)) 3015 return; 3016 3017 if (likely(refcount_read(&skb->users) == 1)) { 3018 smp_rmb(); 3019 refcount_set(&skb->users, 0); 3020 } else if (likely(!refcount_dec_and_test(&skb->users))) { 3021 return; 3022 } 3023 get_kfree_skb_cb(skb)->reason = reason; 3024 local_irq_save(flags); 3025 skb->next = __this_cpu_read(softnet_data.completion_queue); 3026 __this_cpu_write(softnet_data.completion_queue, skb); 3027 raise_softirq_irqoff(NET_TX_SOFTIRQ); 3028 local_irq_restore(flags); 3029 } 3030 EXPORT_SYMBOL(__dev_kfree_skb_irq); 3031 3032 void __dev_kfree_skb_any(struct sk_buff *skb, enum skb_free_reason reason) 3033 { 3034 if (in_hardirq() || irqs_disabled()) 3035 __dev_kfree_skb_irq(skb, reason); 3036 else 3037 dev_kfree_skb(skb); 3038 } 3039 EXPORT_SYMBOL(__dev_kfree_skb_any); 3040 3041 3042 /** 3043 * netif_device_detach - mark device as removed 3044 * @dev: network device 3045 * 3046 * Mark device as removed from system and therefore no longer available. 3047 */ 3048 void netif_device_detach(struct net_device *dev) 3049 { 3050 if (test_and_clear_bit(__LINK_STATE_PRESENT, &dev->state) && 3051 netif_running(dev)) { 3052 netif_tx_stop_all_queues(dev); 3053 } 3054 } 3055 EXPORT_SYMBOL(netif_device_detach); 3056 3057 /** 3058 * netif_device_attach - mark device as attached 3059 * @dev: network device 3060 * 3061 * Mark device as attached from system and restart if needed. 3062 */ 3063 void netif_device_attach(struct net_device *dev) 3064 { 3065 if (!test_and_set_bit(__LINK_STATE_PRESENT, &dev->state) && 3066 netif_running(dev)) { 3067 netif_tx_wake_all_queues(dev); 3068 __netdev_watchdog_up(dev); 3069 } 3070 } 3071 EXPORT_SYMBOL(netif_device_attach); 3072 3073 /* 3074 * Returns a Tx hash based on the given packet descriptor a Tx queues' number 3075 * to be used as a distribution range. 3076 */ 3077 static u16 skb_tx_hash(const struct net_device *dev, 3078 const struct net_device *sb_dev, 3079 struct sk_buff *skb) 3080 { 3081 u32 hash; 3082 u16 qoffset = 0; 3083 u16 qcount = dev->real_num_tx_queues; 3084 3085 if (dev->num_tc) { 3086 u8 tc = netdev_get_prio_tc_map(dev, skb->priority); 3087 3088 qoffset = sb_dev->tc_to_txq[tc].offset; 3089 qcount = sb_dev->tc_to_txq[tc].count; 3090 if (unlikely(!qcount)) { 3091 net_warn_ratelimited("%s: invalid qcount, qoffset %u for tc %u\n", 3092 sb_dev->name, qoffset, tc); 3093 qoffset = 0; 3094 qcount = dev->real_num_tx_queues; 3095 } 3096 } 3097 3098 if (skb_rx_queue_recorded(skb)) { 3099 hash = skb_get_rx_queue(skb); 3100 if (hash >= qoffset) 3101 hash -= qoffset; 3102 while (unlikely(hash >= qcount)) 3103 hash -= qcount; 3104 return hash + qoffset; 3105 } 3106 3107 return (u16) reciprocal_scale(skb_get_hash(skb), qcount) + qoffset; 3108 } 3109 3110 static void skb_warn_bad_offload(const struct sk_buff *skb) 3111 { 3112 static const netdev_features_t null_features; 3113 struct net_device *dev = skb->dev; 3114 const char *name = ""; 3115 3116 if (!net_ratelimit()) 3117 return; 3118 3119 if (dev) { 3120 if (dev->dev.parent) 3121 name = dev_driver_string(dev->dev.parent); 3122 else 3123 name = netdev_name(dev); 3124 } 3125 skb_dump(KERN_WARNING, skb, false); 3126 WARN(1, "%s: caps=(%pNF, %pNF)\n", 3127 name, dev ? &dev->features : &null_features, 3128 skb->sk ? &skb->sk->sk_route_caps : &null_features); 3129 } 3130 3131 /* 3132 * Invalidate hardware checksum when packet is to be mangled, and 3133 * complete checksum manually on outgoing path. 3134 */ 3135 int skb_checksum_help(struct sk_buff *skb) 3136 { 3137 __wsum csum; 3138 int ret = 0, offset; 3139 3140 if (skb->ip_summed == CHECKSUM_COMPLETE) 3141 goto out_set_summed; 3142 3143 if (unlikely(skb_is_gso(skb))) { 3144 skb_warn_bad_offload(skb); 3145 return -EINVAL; 3146 } 3147 3148 /* Before computing a checksum, we should make sure no frag could 3149 * be modified by an external entity : checksum could be wrong. 3150 */ 3151 if (skb_has_shared_frag(skb)) { 3152 ret = __skb_linearize(skb); 3153 if (ret) 3154 goto out; 3155 } 3156 3157 offset = skb_checksum_start_offset(skb); 3158 BUG_ON(offset >= skb_headlen(skb)); 3159 csum = skb_checksum(skb, offset, skb->len - offset, 0); 3160 3161 offset += skb->csum_offset; 3162 BUG_ON(offset + sizeof(__sum16) > skb_headlen(skb)); 3163 3164 ret = skb_ensure_writable(skb, offset + sizeof(__sum16)); 3165 if (ret) 3166 goto out; 3167 3168 *(__sum16 *)(skb->data + offset) = csum_fold(csum) ?: CSUM_MANGLED_0; 3169 out_set_summed: 3170 skb->ip_summed = CHECKSUM_NONE; 3171 out: 3172 return ret; 3173 } 3174 EXPORT_SYMBOL(skb_checksum_help); 3175 3176 int skb_crc32c_csum_help(struct sk_buff *skb) 3177 { 3178 __le32 crc32c_csum; 3179 int ret = 0, offset, start; 3180 3181 if (skb->ip_summed != CHECKSUM_PARTIAL) 3182 goto out; 3183 3184 if (unlikely(skb_is_gso(skb))) 3185 goto out; 3186 3187 /* Before computing a checksum, we should make sure no frag could 3188 * be modified by an external entity : checksum could be wrong. 3189 */ 3190 if (unlikely(skb_has_shared_frag(skb))) { 3191 ret = __skb_linearize(skb); 3192 if (ret) 3193 goto out; 3194 } 3195 start = skb_checksum_start_offset(skb); 3196 offset = start + offsetof(struct sctphdr, checksum); 3197 if (WARN_ON_ONCE(offset >= skb_headlen(skb))) { 3198 ret = -EINVAL; 3199 goto out; 3200 } 3201 3202 ret = skb_ensure_writable(skb, offset + sizeof(__le32)); 3203 if (ret) 3204 goto out; 3205 3206 crc32c_csum = cpu_to_le32(~__skb_checksum(skb, start, 3207 skb->len - start, ~(__u32)0, 3208 crc32c_csum_stub)); 3209 *(__le32 *)(skb->data + offset) = crc32c_csum; 3210 skb->ip_summed = CHECKSUM_NONE; 3211 skb->csum_not_inet = 0; 3212 out: 3213 return ret; 3214 } 3215 3216 __be16 skb_network_protocol(struct sk_buff *skb, int *depth) 3217 { 3218 __be16 type = skb->protocol; 3219 3220 /* Tunnel gso handlers can set protocol to ethernet. */ 3221 if (type == htons(ETH_P_TEB)) { 3222 struct ethhdr *eth; 3223 3224 if (unlikely(!pskb_may_pull(skb, sizeof(struct ethhdr)))) 3225 return 0; 3226 3227 eth = (struct ethhdr *)skb->data; 3228 type = eth->h_proto; 3229 } 3230 3231 return __vlan_get_protocol(skb, type, depth); 3232 } 3233 3234 /* openvswitch calls this on rx path, so we need a different check. 3235 */ 3236 static inline bool skb_needs_check(struct sk_buff *skb, bool tx_path) 3237 { 3238 if (tx_path) 3239 return skb->ip_summed != CHECKSUM_PARTIAL && 3240 skb->ip_summed != CHECKSUM_UNNECESSARY; 3241 3242 return skb->ip_summed == CHECKSUM_NONE; 3243 } 3244 3245 /** 3246 * __skb_gso_segment - Perform segmentation on skb. 3247 * @skb: buffer to segment 3248 * @features: features for the output path (see dev->features) 3249 * @tx_path: whether it is called in TX path 3250 * 3251 * This function segments the given skb and returns a list of segments. 3252 * 3253 * It may return NULL if the skb requires no segmentation. This is 3254 * only possible when GSO is used for verifying header integrity. 3255 * 3256 * Segmentation preserves SKB_GSO_CB_OFFSET bytes of previous skb cb. 3257 */ 3258 struct sk_buff *__skb_gso_segment(struct sk_buff *skb, 3259 netdev_features_t features, bool tx_path) 3260 { 3261 struct sk_buff *segs; 3262 3263 if (unlikely(skb_needs_check(skb, tx_path))) { 3264 int err; 3265 3266 /* We're going to init ->check field in TCP or UDP header */ 3267 err = skb_cow_head(skb, 0); 3268 if (err < 0) 3269 return ERR_PTR(err); 3270 } 3271 3272 /* Only report GSO partial support if it will enable us to 3273 * support segmentation on this frame without needing additional 3274 * work. 3275 */ 3276 if (features & NETIF_F_GSO_PARTIAL) { 3277 netdev_features_t partial_features = NETIF_F_GSO_ROBUST; 3278 struct net_device *dev = skb->dev; 3279 3280 partial_features |= dev->features & dev->gso_partial_features; 3281 if (!skb_gso_ok(skb, features | partial_features)) 3282 features &= ~NETIF_F_GSO_PARTIAL; 3283 } 3284 3285 BUILD_BUG_ON(SKB_GSO_CB_OFFSET + 3286 sizeof(*SKB_GSO_CB(skb)) > sizeof(skb->cb)); 3287 3288 SKB_GSO_CB(skb)->mac_offset = skb_headroom(skb); 3289 SKB_GSO_CB(skb)->encap_level = 0; 3290 3291 skb_reset_mac_header(skb); 3292 skb_reset_mac_len(skb); 3293 3294 segs = skb_mac_gso_segment(skb, features); 3295 3296 if (segs != skb && unlikely(skb_needs_check(skb, tx_path) && !IS_ERR(segs))) 3297 skb_warn_bad_offload(skb); 3298 3299 return segs; 3300 } 3301 EXPORT_SYMBOL(__skb_gso_segment); 3302 3303 /* Take action when hardware reception checksum errors are detected. */ 3304 #ifdef CONFIG_BUG 3305 static void do_netdev_rx_csum_fault(struct net_device *dev, struct sk_buff *skb) 3306 { 3307 netdev_err(dev, "hw csum failure\n"); 3308 skb_dump(KERN_ERR, skb, true); 3309 dump_stack(); 3310 } 3311 3312 void netdev_rx_csum_fault(struct net_device *dev, struct sk_buff *skb) 3313 { 3314 DO_ONCE_LITE(do_netdev_rx_csum_fault, dev, skb); 3315 } 3316 EXPORT_SYMBOL(netdev_rx_csum_fault); 3317 #endif 3318 3319 /* XXX: check that highmem exists at all on the given machine. */ 3320 static int illegal_highdma(struct net_device *dev, struct sk_buff *skb) 3321 { 3322 #ifdef CONFIG_HIGHMEM 3323 int i; 3324 3325 if (!(dev->features & NETIF_F_HIGHDMA)) { 3326 for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) { 3327 skb_frag_t *frag = &skb_shinfo(skb)->frags[i]; 3328 3329 if (PageHighMem(skb_frag_page(frag))) 3330 return 1; 3331 } 3332 } 3333 #endif 3334 return 0; 3335 } 3336 3337 /* If MPLS offload request, verify we are testing hardware MPLS features 3338 * instead of standard features for the netdev. 3339 */ 3340 #if IS_ENABLED(CONFIG_NET_MPLS_GSO) 3341 static netdev_features_t net_mpls_features(struct sk_buff *skb, 3342 netdev_features_t features, 3343 __be16 type) 3344 { 3345 if (eth_p_mpls(type)) 3346 features &= skb->dev->mpls_features; 3347 3348 return features; 3349 } 3350 #else 3351 static netdev_features_t net_mpls_features(struct sk_buff *skb, 3352 netdev_features_t features, 3353 __be16 type) 3354 { 3355 return features; 3356 } 3357 #endif 3358 3359 static netdev_features_t harmonize_features(struct sk_buff *skb, 3360 netdev_features_t features) 3361 { 3362 __be16 type; 3363 3364 type = skb_network_protocol(skb, NULL); 3365 features = net_mpls_features(skb, features, type); 3366 3367 if (skb->ip_summed != CHECKSUM_NONE && 3368 !can_checksum_protocol(features, type)) { 3369 features &= ~(NETIF_F_CSUM_MASK | NETIF_F_GSO_MASK); 3370 } 3371 if (illegal_highdma(skb->dev, skb)) 3372 features &= ~NETIF_F_SG; 3373 3374 return features; 3375 } 3376 3377 netdev_features_t passthru_features_check(struct sk_buff *skb, 3378 struct net_device *dev, 3379 netdev_features_t features) 3380 { 3381 return features; 3382 } 3383 EXPORT_SYMBOL(passthru_features_check); 3384 3385 static netdev_features_t dflt_features_check(struct sk_buff *skb, 3386 struct net_device *dev, 3387 netdev_features_t features) 3388 { 3389 return vlan_features_check(skb, features); 3390 } 3391 3392 static netdev_features_t gso_features_check(const struct sk_buff *skb, 3393 struct net_device *dev, 3394 netdev_features_t features) 3395 { 3396 u16 gso_segs = skb_shinfo(skb)->gso_segs; 3397 3398 if (gso_segs > dev->gso_max_segs) 3399 return features & ~NETIF_F_GSO_MASK; 3400 3401 if (!skb_shinfo(skb)->gso_type) { 3402 skb_warn_bad_offload(skb); 3403 return features & ~NETIF_F_GSO_MASK; 3404 } 3405 3406 /* Support for GSO partial features requires software 3407 * intervention before we can actually process the packets 3408 * so we need to strip support for any partial features now 3409 * and we can pull them back in after we have partially 3410 * segmented the frame. 3411 */ 3412 if (!(skb_shinfo(skb)->gso_type & SKB_GSO_PARTIAL)) 3413 features &= ~dev->gso_partial_features; 3414 3415 /* Make sure to clear the IPv4 ID mangling feature if the 3416 * IPv4 header has the potential to be fragmented. 3417 */ 3418 if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV4) { 3419 struct iphdr *iph = skb->encapsulation ? 3420 inner_ip_hdr(skb) : ip_hdr(skb); 3421 3422 if (!(iph->frag_off & htons(IP_DF))) 3423 features &= ~NETIF_F_TSO_MANGLEID; 3424 } 3425 3426 return features; 3427 } 3428 3429 netdev_features_t netif_skb_features(struct sk_buff *skb) 3430 { 3431 struct net_device *dev = skb->dev; 3432 netdev_features_t features = dev->features; 3433 3434 if (skb_is_gso(skb)) 3435 features = gso_features_check(skb, dev, features); 3436 3437 /* If encapsulation offload request, verify we are testing 3438 * hardware encapsulation features instead of standard 3439 * features for the netdev 3440 */ 3441 if (skb->encapsulation) 3442 features &= dev->hw_enc_features; 3443 3444 if (skb_vlan_tagged(skb)) 3445 features = netdev_intersect_features(features, 3446 dev->vlan_features | 3447 NETIF_F_HW_VLAN_CTAG_TX | 3448 NETIF_F_HW_VLAN_STAG_TX); 3449 3450 if (dev->netdev_ops->ndo_features_check) 3451 features &= dev->netdev_ops->ndo_features_check(skb, dev, 3452 features); 3453 else 3454 features &= dflt_features_check(skb, dev, features); 3455 3456 return harmonize_features(skb, features); 3457 } 3458 EXPORT_SYMBOL(netif_skb_features); 3459 3460 static int xmit_one(struct sk_buff *skb, struct net_device *dev, 3461 struct netdev_queue *txq, bool more) 3462 { 3463 unsigned int len; 3464 int rc; 3465 3466 if (dev_nit_active(dev)) 3467 dev_queue_xmit_nit(skb, dev); 3468 3469 len = skb->len; 3470 PRANDOM_ADD_NOISE(skb, dev, txq, len + jiffies); 3471 trace_net_dev_start_xmit(skb, dev); 3472 rc = netdev_start_xmit(skb, dev, txq, more); 3473 trace_net_dev_xmit(skb, rc, dev, len); 3474 3475 return rc; 3476 } 3477 3478 struct sk_buff *dev_hard_start_xmit(struct sk_buff *first, struct net_device *dev, 3479 struct netdev_queue *txq, int *ret) 3480 { 3481 struct sk_buff *skb = first; 3482 int rc = NETDEV_TX_OK; 3483 3484 while (skb) { 3485 struct sk_buff *next = skb->next; 3486 3487 skb_mark_not_on_list(skb); 3488 rc = xmit_one(skb, dev, txq, next != NULL); 3489 if (unlikely(!dev_xmit_complete(rc))) { 3490 skb->next = next; 3491 goto out; 3492 } 3493 3494 skb = next; 3495 if (netif_tx_queue_stopped(txq) && skb) { 3496 rc = NETDEV_TX_BUSY; 3497 break; 3498 } 3499 } 3500 3501 out: 3502 *ret = rc; 3503 return skb; 3504 } 3505 3506 static struct sk_buff *validate_xmit_vlan(struct sk_buff *skb, 3507 netdev_features_t features) 3508 { 3509 if (skb_vlan_tag_present(skb) && 3510 !vlan_hw_offload_capable(features, skb->vlan_proto)) 3511 skb = __vlan_hwaccel_push_inside(skb); 3512 return skb; 3513 } 3514 3515 int skb_csum_hwoffload_help(struct sk_buff *skb, 3516 const netdev_features_t features) 3517 { 3518 if (unlikely(skb_csum_is_sctp(skb))) 3519 return !!(features & NETIF_F_SCTP_CRC) ? 0 : 3520 skb_crc32c_csum_help(skb); 3521 3522 if (features & NETIF_F_HW_CSUM) 3523 return 0; 3524 3525 if (features & (NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM)) { 3526 switch (skb->csum_offset) { 3527 case offsetof(struct tcphdr, check): 3528 case offsetof(struct udphdr, check): 3529 return 0; 3530 } 3531 } 3532 3533 return skb_checksum_help(skb); 3534 } 3535 EXPORT_SYMBOL(skb_csum_hwoffload_help); 3536 3537 static struct sk_buff *validate_xmit_skb(struct sk_buff *skb, struct net_device *dev, bool *again) 3538 { 3539 netdev_features_t features; 3540 3541 features = netif_skb_features(skb); 3542 skb = validate_xmit_vlan(skb, features); 3543 if (unlikely(!skb)) 3544 goto out_null; 3545 3546 skb = sk_validate_xmit_skb(skb, dev); 3547 if (unlikely(!skb)) 3548 goto out_null; 3549 3550 if (netif_needs_gso(skb, features)) { 3551 struct sk_buff *segs; 3552 3553 segs = skb_gso_segment(skb, features); 3554 if (IS_ERR(segs)) { 3555 goto out_kfree_skb; 3556 } else if (segs) { 3557 consume_skb(skb); 3558 skb = segs; 3559 } 3560 } else { 3561 if (skb_needs_linearize(skb, features) && 3562 __skb_linearize(skb)) 3563 goto out_kfree_skb; 3564 3565 /* If packet is not checksummed and device does not 3566 * support checksumming for this protocol, complete 3567 * checksumming here. 3568 */ 3569 if (skb->ip_summed == CHECKSUM_PARTIAL) { 3570 if (skb->encapsulation) 3571 skb_set_inner_transport_header(skb, 3572 skb_checksum_start_offset(skb)); 3573 else 3574 skb_set_transport_header(skb, 3575 skb_checksum_start_offset(skb)); 3576 if (skb_csum_hwoffload_help(skb, features)) 3577 goto out_kfree_skb; 3578 } 3579 } 3580 3581 skb = validate_xmit_xfrm(skb, features, again); 3582 3583 return skb; 3584 3585 out_kfree_skb: 3586 kfree_skb(skb); 3587 out_null: 3588 atomic_long_inc(&dev->tx_dropped); 3589 return NULL; 3590 } 3591 3592 struct sk_buff *validate_xmit_skb_list(struct sk_buff *skb, struct net_device *dev, bool *again) 3593 { 3594 struct sk_buff *next, *head = NULL, *tail; 3595 3596 for (; skb != NULL; skb = next) { 3597 next = skb->next; 3598 skb_mark_not_on_list(skb); 3599 3600 /* in case skb wont be segmented, point to itself */ 3601 skb->prev = skb; 3602 3603 skb = validate_xmit_skb(skb, dev, again); 3604 if (!skb) 3605 continue; 3606 3607 if (!head) 3608 head = skb; 3609 else 3610 tail->next = skb; 3611 /* If skb was segmented, skb->prev points to 3612 * the last segment. If not, it still contains skb. 3613 */ 3614 tail = skb->prev; 3615 } 3616 return head; 3617 } 3618 EXPORT_SYMBOL_GPL(validate_xmit_skb_list); 3619 3620 static void qdisc_pkt_len_init(struct sk_buff *skb) 3621 { 3622 const struct skb_shared_info *shinfo = skb_shinfo(skb); 3623 3624 qdisc_skb_cb(skb)->pkt_len = skb->len; 3625 3626 /* To get more precise estimation of bytes sent on wire, 3627 * we add to pkt_len the headers size of all segments 3628 */ 3629 if (shinfo->gso_size && skb_transport_header_was_set(skb)) { 3630 unsigned int hdr_len; 3631 u16 gso_segs = shinfo->gso_segs; 3632 3633 /* mac layer + network layer */ 3634 hdr_len = skb_transport_header(skb) - skb_mac_header(skb); 3635 3636 /* + transport layer */ 3637 if (likely(shinfo->gso_type & (SKB_GSO_TCPV4 | SKB_GSO_TCPV6))) { 3638 const struct tcphdr *th; 3639 struct tcphdr _tcphdr; 3640 3641 th = skb_header_pointer(skb, skb_transport_offset(skb), 3642 sizeof(_tcphdr), &_tcphdr); 3643 if (likely(th)) 3644 hdr_len += __tcp_hdrlen(th); 3645 } else { 3646 struct udphdr _udphdr; 3647 3648 if (skb_header_pointer(skb, skb_transport_offset(skb), 3649 sizeof(_udphdr), &_udphdr)) 3650 hdr_len += sizeof(struct udphdr); 3651 } 3652 3653 if (shinfo->gso_type & SKB_GSO_DODGY) 3654 gso_segs = DIV_ROUND_UP(skb->len - hdr_len, 3655 shinfo->gso_size); 3656 3657 qdisc_skb_cb(skb)->pkt_len += (gso_segs - 1) * hdr_len; 3658 } 3659 } 3660 3661 static int dev_qdisc_enqueue(struct sk_buff *skb, struct Qdisc *q, 3662 struct sk_buff **to_free, 3663 struct netdev_queue *txq) 3664 { 3665 int rc; 3666 3667 rc = q->enqueue(skb, q, to_free) & NET_XMIT_MASK; 3668 if (rc == NET_XMIT_SUCCESS) 3669 trace_qdisc_enqueue(q, txq, skb); 3670 return rc; 3671 } 3672 3673 static inline int __dev_xmit_skb(struct sk_buff *skb, struct Qdisc *q, 3674 struct net_device *dev, 3675 struct netdev_queue *txq) 3676 { 3677 spinlock_t *root_lock = qdisc_lock(q); 3678 struct sk_buff *to_free = NULL; 3679 bool contended; 3680 int rc; 3681 3682 qdisc_calculate_pkt_len(skb, q); 3683 3684 if (q->flags & TCQ_F_NOLOCK) { 3685 if (q->flags & TCQ_F_CAN_BYPASS && nolock_qdisc_is_empty(q) && 3686 qdisc_run_begin(q)) { 3687 /* Retest nolock_qdisc_is_empty() within the protection 3688 * of q->seqlock to protect from racing with requeuing. 3689 */ 3690 if (unlikely(!nolock_qdisc_is_empty(q))) { 3691 rc = dev_qdisc_enqueue(skb, q, &to_free, txq); 3692 __qdisc_run(q); 3693 qdisc_run_end(q); 3694 3695 goto no_lock_out; 3696 } 3697 3698 qdisc_bstats_cpu_update(q, skb); 3699 if (sch_direct_xmit(skb, q, dev, txq, NULL, true) && 3700 !nolock_qdisc_is_empty(q)) 3701 __qdisc_run(q); 3702 3703 qdisc_run_end(q); 3704 return NET_XMIT_SUCCESS; 3705 } 3706 3707 rc = dev_qdisc_enqueue(skb, q, &to_free, txq); 3708 qdisc_run(q); 3709 3710 no_lock_out: 3711 if (unlikely(to_free)) 3712 kfree_skb_list(to_free); 3713 return rc; 3714 } 3715 3716 /* 3717 * Heuristic to force contended enqueues to serialize on a 3718 * separate lock before trying to get qdisc main lock. 3719 * This permits qdisc->running owner to get the lock more 3720 * often and dequeue packets faster. 3721 */ 3722 contended = qdisc_is_running(q); 3723 if (unlikely(contended)) 3724 spin_lock(&q->busylock); 3725 3726 spin_lock(root_lock); 3727 if (unlikely(test_bit(__QDISC_STATE_DEACTIVATED, &q->state))) { 3728 __qdisc_drop(skb, &to_free); 3729 rc = NET_XMIT_DROP; 3730 } else if ((q->flags & TCQ_F_CAN_BYPASS) && !qdisc_qlen(q) && 3731 qdisc_run_begin(q)) { 3732 /* 3733 * This is a work-conserving queue; there are no old skbs 3734 * waiting to be sent out; and the qdisc is not running - 3735 * xmit the skb directly. 3736 */ 3737 3738 qdisc_bstats_update(q, skb); 3739 3740 if (sch_direct_xmit(skb, q, dev, txq, root_lock, true)) { 3741 if (unlikely(contended)) { 3742 spin_unlock(&q->busylock); 3743 contended = false; 3744 } 3745 __qdisc_run(q); 3746 } 3747 3748 qdisc_run_end(q); 3749 rc = NET_XMIT_SUCCESS; 3750 } else { 3751 rc = dev_qdisc_enqueue(skb, q, &to_free, txq); 3752 if (qdisc_run_begin(q)) { 3753 if (unlikely(contended)) { 3754 spin_unlock(&q->busylock); 3755 contended = false; 3756 } 3757 __qdisc_run(q); 3758 qdisc_run_end(q); 3759 } 3760 } 3761 spin_unlock(root_lock); 3762 if (unlikely(to_free)) 3763 kfree_skb_list(to_free); 3764 if (unlikely(contended)) 3765 spin_unlock(&q->busylock); 3766 return rc; 3767 } 3768 3769 #if IS_ENABLED(CONFIG_CGROUP_NET_PRIO) 3770 static void skb_update_prio(struct sk_buff *skb) 3771 { 3772 const struct netprio_map *map; 3773 const struct sock *sk; 3774 unsigned int prioidx; 3775 3776 if (skb->priority) 3777 return; 3778 map = rcu_dereference_bh(skb->dev->priomap); 3779 if (!map) 3780 return; 3781 sk = skb_to_full_sk(skb); 3782 if (!sk) 3783 return; 3784 3785 prioidx = sock_cgroup_prioidx(&sk->sk_cgrp_data); 3786 3787 if (prioidx < map->priomap_len) 3788 skb->priority = map->priomap[prioidx]; 3789 } 3790 #else 3791 #define skb_update_prio(skb) 3792 #endif 3793 3794 /** 3795 * dev_loopback_xmit - loop back @skb 3796 * @net: network namespace this loopback is happening in 3797 * @sk: sk needed to be a netfilter okfn 3798 * @skb: buffer to transmit 3799 */ 3800 int dev_loopback_xmit(struct net *net, struct sock *sk, struct sk_buff *skb) 3801 { 3802 skb_reset_mac_header(skb); 3803 __skb_pull(skb, skb_network_offset(skb)); 3804 skb->pkt_type = PACKET_LOOPBACK; 3805 if (skb->ip_summed == CHECKSUM_NONE) 3806 skb->ip_summed = CHECKSUM_UNNECESSARY; 3807 WARN_ON(!skb_dst(skb)); 3808 skb_dst_force(skb); 3809 netif_rx_ni(skb); 3810 return 0; 3811 } 3812 EXPORT_SYMBOL(dev_loopback_xmit); 3813 3814 #ifdef CONFIG_NET_EGRESS 3815 static struct sk_buff * 3816 sch_handle_egress(struct sk_buff *skb, int *ret, struct net_device *dev) 3817 { 3818 #ifdef CONFIG_NET_CLS_ACT 3819 struct mini_Qdisc *miniq = rcu_dereference_bh(dev->miniq_egress); 3820 struct tcf_result cl_res; 3821 3822 if (!miniq) 3823 return skb; 3824 3825 /* qdisc_skb_cb(skb)->pkt_len was already set by the caller. */ 3826 qdisc_skb_cb(skb)->mru = 0; 3827 qdisc_skb_cb(skb)->post_ct = false; 3828 mini_qdisc_bstats_cpu_update(miniq, skb); 3829 3830 switch (tcf_classify(skb, miniq->block, miniq->filter_list, &cl_res, false)) { 3831 case TC_ACT_OK: 3832 case TC_ACT_RECLASSIFY: 3833 skb->tc_index = TC_H_MIN(cl_res.classid); 3834 break; 3835 case TC_ACT_SHOT: 3836 mini_qdisc_qstats_cpu_drop(miniq); 3837 *ret = NET_XMIT_DROP; 3838 kfree_skb(skb); 3839 return NULL; 3840 case TC_ACT_STOLEN: 3841 case TC_ACT_QUEUED: 3842 case TC_ACT_TRAP: 3843 *ret = NET_XMIT_SUCCESS; 3844 consume_skb(skb); 3845 return NULL; 3846 case TC_ACT_REDIRECT: 3847 /* No need to push/pop skb's mac_header here on egress! */ 3848 skb_do_redirect(skb); 3849 *ret = NET_XMIT_SUCCESS; 3850 return NULL; 3851 default: 3852 break; 3853 } 3854 #endif /* CONFIG_NET_CLS_ACT */ 3855 3856 return skb; 3857 } 3858 #endif /* CONFIG_NET_EGRESS */ 3859 3860 #ifdef CONFIG_XPS 3861 static int __get_xps_queue_idx(struct net_device *dev, struct sk_buff *skb, 3862 struct xps_dev_maps *dev_maps, unsigned int tci) 3863 { 3864 int tc = netdev_get_prio_tc_map(dev, skb->priority); 3865 struct xps_map *map; 3866 int queue_index = -1; 3867 3868 if (tc >= dev_maps->num_tc || tci >= dev_maps->nr_ids) 3869 return queue_index; 3870 3871 tci *= dev_maps->num_tc; 3872 tci += tc; 3873 3874 map = rcu_dereference(dev_maps->attr_map[tci]); 3875 if (map) { 3876 if (map->len == 1) 3877 queue_index = map->queues[0]; 3878 else 3879 queue_index = map->queues[reciprocal_scale( 3880 skb_get_hash(skb), map->len)]; 3881 if (unlikely(queue_index >= dev->real_num_tx_queues)) 3882 queue_index = -1; 3883 } 3884 return queue_index; 3885 } 3886 #endif 3887 3888 static int get_xps_queue(struct net_device *dev, struct net_device *sb_dev, 3889 struct sk_buff *skb) 3890 { 3891 #ifdef CONFIG_XPS 3892 struct xps_dev_maps *dev_maps; 3893 struct sock *sk = skb->sk; 3894 int queue_index = -1; 3895 3896 if (!static_key_false(&xps_needed)) 3897 return -1; 3898 3899 rcu_read_lock(); 3900 if (!static_key_false(&xps_rxqs_needed)) 3901 goto get_cpus_map; 3902 3903 dev_maps = rcu_dereference(sb_dev->xps_maps[XPS_RXQS]); 3904 if (dev_maps) { 3905 int tci = sk_rx_queue_get(sk); 3906 3907 if (tci >= 0) 3908 queue_index = __get_xps_queue_idx(dev, skb, dev_maps, 3909 tci); 3910 } 3911 3912 get_cpus_map: 3913 if (queue_index < 0) { 3914 dev_maps = rcu_dereference(sb_dev->xps_maps[XPS_CPUS]); 3915 if (dev_maps) { 3916 unsigned int tci = skb->sender_cpu - 1; 3917 3918 queue_index = __get_xps_queue_idx(dev, skb, dev_maps, 3919 tci); 3920 } 3921 } 3922 rcu_read_unlock(); 3923 3924 return queue_index; 3925 #else 3926 return -1; 3927 #endif 3928 } 3929 3930 u16 dev_pick_tx_zero(struct net_device *dev, struct sk_buff *skb, 3931 struct net_device *sb_dev) 3932 { 3933 return 0; 3934 } 3935 EXPORT_SYMBOL(dev_pick_tx_zero); 3936 3937 u16 dev_pick_tx_cpu_id(struct net_device *dev, struct sk_buff *skb, 3938 struct net_device *sb_dev) 3939 { 3940 return (u16)raw_smp_processor_id() % dev->real_num_tx_queues; 3941 } 3942 EXPORT_SYMBOL(dev_pick_tx_cpu_id); 3943 3944 u16 netdev_pick_tx(struct net_device *dev, struct sk_buff *skb, 3945 struct net_device *sb_dev) 3946 { 3947 struct sock *sk = skb->sk; 3948 int queue_index = sk_tx_queue_get(sk); 3949 3950 sb_dev = sb_dev ? : dev; 3951 3952 if (queue_index < 0 || skb->ooo_okay || 3953 queue_index >= dev->real_num_tx_queues) { 3954 int new_index = get_xps_queue(dev, sb_dev, skb); 3955 3956 if (new_index < 0) 3957 new_index = skb_tx_hash(dev, sb_dev, skb); 3958 3959 if (queue_index != new_index && sk && 3960 sk_fullsock(sk) && 3961 rcu_access_pointer(sk->sk_dst_cache)) 3962 sk_tx_queue_set(sk, new_index); 3963 3964 queue_index = new_index; 3965 } 3966 3967 return queue_index; 3968 } 3969 EXPORT_SYMBOL(netdev_pick_tx); 3970 3971 struct netdev_queue *netdev_core_pick_tx(struct net_device *dev, 3972 struct sk_buff *skb, 3973 struct net_device *sb_dev) 3974 { 3975 int queue_index = 0; 3976 3977 #ifdef CONFIG_XPS 3978 u32 sender_cpu = skb->sender_cpu - 1; 3979 3980 if (sender_cpu >= (u32)NR_CPUS) 3981 skb->sender_cpu = raw_smp_processor_id() + 1; 3982 #endif 3983 3984 if (dev->real_num_tx_queues != 1) { 3985 const struct net_device_ops *ops = dev->netdev_ops; 3986 3987 if (ops->ndo_select_queue) 3988 queue_index = ops->ndo_select_queue(dev, skb, sb_dev); 3989 else 3990 queue_index = netdev_pick_tx(dev, skb, sb_dev); 3991 3992 queue_index = netdev_cap_txqueue(dev, queue_index); 3993 } 3994 3995 skb_set_queue_mapping(skb, queue_index); 3996 return netdev_get_tx_queue(dev, queue_index); 3997 } 3998 3999 /** 4000 * __dev_queue_xmit - transmit a buffer 4001 * @skb: buffer to transmit 4002 * @sb_dev: suboordinate device used for L2 forwarding offload 4003 * 4004 * Queue a buffer for transmission to a network device. The caller must 4005 * have set the device and priority and built the buffer before calling 4006 * this function. The function can be called from an interrupt. 4007 * 4008 * A negative errno code is returned on a failure. A success does not 4009 * guarantee the frame will be transmitted as it may be dropped due 4010 * to congestion or traffic shaping. 4011 * 4012 * ----------------------------------------------------------------------------------- 4013 * I notice this method can also return errors from the queue disciplines, 4014 * including NET_XMIT_DROP, which is a positive value. So, errors can also 4015 * be positive. 4016 * 4017 * Regardless of the return value, the skb is consumed, so it is currently 4018 * difficult to retry a send to this method. (You can bump the ref count 4019 * before sending to hold a reference for retry if you are careful.) 4020 * 4021 * When calling this method, interrupts MUST be enabled. This is because 4022 * the BH enable code must have IRQs enabled so that it will not deadlock. 4023 * --BLG 4024 */ 4025 static int __dev_queue_xmit(struct sk_buff *skb, struct net_device *sb_dev) 4026 { 4027 struct net_device *dev = skb->dev; 4028 struct netdev_queue *txq; 4029 struct Qdisc *q; 4030 int rc = -ENOMEM; 4031 bool again = false; 4032 4033 skb_reset_mac_header(skb); 4034 4035 if (unlikely(skb_shinfo(skb)->tx_flags & SKBTX_SCHED_TSTAMP)) 4036 __skb_tstamp_tx(skb, NULL, NULL, skb->sk, SCM_TSTAMP_SCHED); 4037 4038 /* Disable soft irqs for various locks below. Also 4039 * stops preemption for RCU. 4040 */ 4041 rcu_read_lock_bh(); 4042 4043 skb_update_prio(skb); 4044 4045 qdisc_pkt_len_init(skb); 4046 #ifdef CONFIG_NET_CLS_ACT 4047 skb->tc_at_ingress = 0; 4048 #endif 4049 #ifdef CONFIG_NET_EGRESS 4050 if (static_branch_unlikely(&egress_needed_key)) { 4051 if (nf_hook_egress_active()) { 4052 skb = nf_hook_egress(skb, &rc, dev); 4053 if (!skb) 4054 goto out; 4055 } 4056 nf_skip_egress(skb, true); 4057 skb = sch_handle_egress(skb, &rc, dev); 4058 if (!skb) 4059 goto out; 4060 nf_skip_egress(skb, false); 4061 } 4062 #endif 4063 /* If device/qdisc don't need skb->dst, release it right now while 4064 * its hot in this cpu cache. 4065 */ 4066 if (dev->priv_flags & IFF_XMIT_DST_RELEASE) 4067 skb_dst_drop(skb); 4068 else 4069 skb_dst_force(skb); 4070 4071 txq = netdev_core_pick_tx(dev, skb, sb_dev); 4072 q = rcu_dereference_bh(txq->qdisc); 4073 4074 trace_net_dev_queue(skb); 4075 if (q->enqueue) { 4076 rc = __dev_xmit_skb(skb, q, dev, txq); 4077 goto out; 4078 } 4079 4080 /* The device has no queue. Common case for software devices: 4081 * loopback, all the sorts of tunnels... 4082 4083 * Really, it is unlikely that netif_tx_lock protection is necessary 4084 * here. (f.e. loopback and IP tunnels are clean ignoring statistics 4085 * counters.) 4086 * However, it is possible, that they rely on protection 4087 * made by us here. 4088 4089 * Check this and shot the lock. It is not prone from deadlocks. 4090 *Either shot noqueue qdisc, it is even simpler 8) 4091 */ 4092 if (dev->flags & IFF_UP) { 4093 int cpu = smp_processor_id(); /* ok because BHs are off */ 4094 4095 if (txq->xmit_lock_owner != cpu) { 4096 if (dev_xmit_recursion()) 4097 goto recursion_alert; 4098 4099 skb = validate_xmit_skb(skb, dev, &again); 4100 if (!skb) 4101 goto out; 4102 4103 PRANDOM_ADD_NOISE(skb, dev, txq, jiffies); 4104 HARD_TX_LOCK(dev, txq, cpu); 4105 4106 if (!netif_xmit_stopped(txq)) { 4107 dev_xmit_recursion_inc(); 4108 skb = dev_hard_start_xmit(skb, dev, txq, &rc); 4109 dev_xmit_recursion_dec(); 4110 if (dev_xmit_complete(rc)) { 4111 HARD_TX_UNLOCK(dev, txq); 4112 goto out; 4113 } 4114 } 4115 HARD_TX_UNLOCK(dev, txq); 4116 net_crit_ratelimited("Virtual device %s asks to queue packet!\n", 4117 dev->name); 4118 } else { 4119 /* Recursion is detected! It is possible, 4120 * unfortunately 4121 */ 4122 recursion_alert: 4123 net_crit_ratelimited("Dead loop on virtual device %s, fix it urgently!\n", 4124 dev->name); 4125 } 4126 } 4127 4128 rc = -ENETDOWN; 4129 rcu_read_unlock_bh(); 4130 4131 atomic_long_inc(&dev->tx_dropped); 4132 kfree_skb_list(skb); 4133 return rc; 4134 out: 4135 rcu_read_unlock_bh(); 4136 return rc; 4137 } 4138 4139 int dev_queue_xmit(struct sk_buff *skb) 4140 { 4141 return __dev_queue_xmit(skb, NULL); 4142 } 4143 EXPORT_SYMBOL(dev_queue_xmit); 4144 4145 int dev_queue_xmit_accel(struct sk_buff *skb, struct net_device *sb_dev) 4146 { 4147 return __dev_queue_xmit(skb, sb_dev); 4148 } 4149 EXPORT_SYMBOL(dev_queue_xmit_accel); 4150 4151 int __dev_direct_xmit(struct sk_buff *skb, u16 queue_id) 4152 { 4153 struct net_device *dev = skb->dev; 4154 struct sk_buff *orig_skb = skb; 4155 struct netdev_queue *txq; 4156 int ret = NETDEV_TX_BUSY; 4157 bool again = false; 4158 4159 if (unlikely(!netif_running(dev) || 4160 !netif_carrier_ok(dev))) 4161 goto drop; 4162 4163 skb = validate_xmit_skb_list(skb, dev, &again); 4164 if (skb != orig_skb) 4165 goto drop; 4166 4167 skb_set_queue_mapping(skb, queue_id); 4168 txq = skb_get_tx_queue(dev, skb); 4169 PRANDOM_ADD_NOISE(skb, dev, txq, jiffies); 4170 4171 local_bh_disable(); 4172 4173 dev_xmit_recursion_inc(); 4174 HARD_TX_LOCK(dev, txq, smp_processor_id()); 4175 if (!netif_xmit_frozen_or_drv_stopped(txq)) 4176 ret = netdev_start_xmit(skb, dev, txq, false); 4177 HARD_TX_UNLOCK(dev, txq); 4178 dev_xmit_recursion_dec(); 4179 4180 local_bh_enable(); 4181 return ret; 4182 drop: 4183 atomic_long_inc(&dev->tx_dropped); 4184 kfree_skb_list(skb); 4185 return NET_XMIT_DROP; 4186 } 4187 EXPORT_SYMBOL(__dev_direct_xmit); 4188 4189 /************************************************************************* 4190 * Receiver routines 4191 *************************************************************************/ 4192 4193 int netdev_max_backlog __read_mostly = 1000; 4194 EXPORT_SYMBOL(netdev_max_backlog); 4195 4196 int netdev_tstamp_prequeue __read_mostly = 1; 4197 int netdev_budget __read_mostly = 300; 4198 /* Must be at least 2 jiffes to guarantee 1 jiffy timeout */ 4199 unsigned int __read_mostly netdev_budget_usecs = 2 * USEC_PER_SEC / HZ; 4200 int weight_p __read_mostly = 64; /* old backlog weight */ 4201 int dev_weight_rx_bias __read_mostly = 1; /* bias for backlog weight */ 4202 int dev_weight_tx_bias __read_mostly = 1; /* bias for output_queue quota */ 4203 int dev_rx_weight __read_mostly = 64; 4204 int dev_tx_weight __read_mostly = 64; 4205 4206 /* Called with irq disabled */ 4207 static inline void ____napi_schedule(struct softnet_data *sd, 4208 struct napi_struct *napi) 4209 { 4210 struct task_struct *thread; 4211 4212 if (test_bit(NAPI_STATE_THREADED, &napi->state)) { 4213 /* Paired with smp_mb__before_atomic() in 4214 * napi_enable()/dev_set_threaded(). 4215 * Use READ_ONCE() to guarantee a complete 4216 * read on napi->thread. Only call 4217 * wake_up_process() when it's not NULL. 4218 */ 4219 thread = READ_ONCE(napi->thread); 4220 if (thread) { 4221 /* Avoid doing set_bit() if the thread is in 4222 * INTERRUPTIBLE state, cause napi_thread_wait() 4223 * makes sure to proceed with napi polling 4224 * if the thread is explicitly woken from here. 4225 */ 4226 if (READ_ONCE(thread->__state) != TASK_INTERRUPTIBLE) 4227 set_bit(NAPI_STATE_SCHED_THREADED, &napi->state); 4228 wake_up_process(thread); 4229 return; 4230 } 4231 } 4232 4233 list_add_tail(&napi->poll_list, &sd->poll_list); 4234 __raise_softirq_irqoff(NET_RX_SOFTIRQ); 4235 } 4236 4237 #ifdef CONFIG_RPS 4238 4239 /* One global table that all flow-based protocols share. */ 4240 struct rps_sock_flow_table __rcu *rps_sock_flow_table __read_mostly; 4241 EXPORT_SYMBOL(rps_sock_flow_table); 4242 u32 rps_cpu_mask __read_mostly; 4243 EXPORT_SYMBOL(rps_cpu_mask); 4244 4245 struct static_key_false rps_needed __read_mostly; 4246 EXPORT_SYMBOL(rps_needed); 4247 struct static_key_false rfs_needed __read_mostly; 4248 EXPORT_SYMBOL(rfs_needed); 4249 4250 static struct rps_dev_flow * 4251 set_rps_cpu(struct net_device *dev, struct sk_buff *skb, 4252 struct rps_dev_flow *rflow, u16 next_cpu) 4253 { 4254 if (next_cpu < nr_cpu_ids) { 4255 #ifdef CONFIG_RFS_ACCEL 4256 struct netdev_rx_queue *rxqueue; 4257 struct rps_dev_flow_table *flow_table; 4258 struct rps_dev_flow *old_rflow; 4259 u32 flow_id; 4260 u16 rxq_index; 4261 int rc; 4262 4263 /* Should we steer this flow to a different hardware queue? */ 4264 if (!skb_rx_queue_recorded(skb) || !dev->rx_cpu_rmap || 4265 !(dev->features & NETIF_F_NTUPLE)) 4266 goto out; 4267 rxq_index = cpu_rmap_lookup_index(dev->rx_cpu_rmap, next_cpu); 4268 if (rxq_index == skb_get_rx_queue(skb)) 4269 goto out; 4270 4271 rxqueue = dev->_rx + rxq_index; 4272 flow_table = rcu_dereference(rxqueue->rps_flow_table); 4273 if (!flow_table) 4274 goto out; 4275 flow_id = skb_get_hash(skb) & flow_table->mask; 4276 rc = dev->netdev_ops->ndo_rx_flow_steer(dev, skb, 4277 rxq_index, flow_id); 4278 if (rc < 0) 4279 goto out; 4280 old_rflow = rflow; 4281 rflow = &flow_table->flows[flow_id]; 4282 rflow->filter = rc; 4283 if (old_rflow->filter == rflow->filter) 4284 old_rflow->filter = RPS_NO_FILTER; 4285 out: 4286 #endif 4287 rflow->last_qtail = 4288 per_cpu(softnet_data, next_cpu).input_queue_head; 4289 } 4290 4291 rflow->cpu = next_cpu; 4292 return rflow; 4293 } 4294 4295 /* 4296 * get_rps_cpu is called from netif_receive_skb and returns the target 4297 * CPU from the RPS map of the receiving queue for a given skb. 4298 * rcu_read_lock must be held on entry. 4299 */ 4300 static int get_rps_cpu(struct net_device *dev, struct sk_buff *skb, 4301 struct rps_dev_flow **rflowp) 4302 { 4303 const struct rps_sock_flow_table *sock_flow_table; 4304 struct netdev_rx_queue *rxqueue = dev->_rx; 4305 struct rps_dev_flow_table *flow_table; 4306 struct rps_map *map; 4307 int cpu = -1; 4308 u32 tcpu; 4309 u32 hash; 4310 4311 if (skb_rx_queue_recorded(skb)) { 4312 u16 index = skb_get_rx_queue(skb); 4313 4314 if (unlikely(index >= dev->real_num_rx_queues)) { 4315 WARN_ONCE(dev->real_num_rx_queues > 1, 4316 "%s received packet on queue %u, but number " 4317 "of RX queues is %u\n", 4318 dev->name, index, dev->real_num_rx_queues); 4319 goto done; 4320 } 4321 rxqueue += index; 4322 } 4323 4324 /* Avoid computing hash if RFS/RPS is not active for this rxqueue */ 4325 4326 flow_table = rcu_dereference(rxqueue->rps_flow_table); 4327 map = rcu_dereference(rxqueue->rps_map); 4328 if (!flow_table && !map) 4329 goto done; 4330 4331 skb_reset_network_header(skb); 4332 hash = skb_get_hash(skb); 4333 if (!hash) 4334 goto done; 4335 4336 sock_flow_table = rcu_dereference(rps_sock_flow_table); 4337 if (flow_table && sock_flow_table) { 4338 struct rps_dev_flow *rflow; 4339 u32 next_cpu; 4340 u32 ident; 4341 4342 /* First check into global flow table if there is a match */ 4343 ident = sock_flow_table->ents[hash & sock_flow_table->mask]; 4344 if ((ident ^ hash) & ~rps_cpu_mask) 4345 goto try_rps; 4346 4347 next_cpu = ident & rps_cpu_mask; 4348 4349 /* OK, now we know there is a match, 4350 * we can look at the local (per receive queue) flow table 4351 */ 4352 rflow = &flow_table->flows[hash & flow_table->mask]; 4353 tcpu = rflow->cpu; 4354 4355 /* 4356 * If the desired CPU (where last recvmsg was done) is 4357 * different from current CPU (one in the rx-queue flow 4358 * table entry), switch if one of the following holds: 4359 * - Current CPU is unset (>= nr_cpu_ids). 4360 * - Current CPU is offline. 4361 * - The current CPU's queue tail has advanced beyond the 4362 * last packet that was enqueued using this table entry. 4363 * This guarantees that all previous packets for the flow 4364 * have been dequeued, thus preserving in order delivery. 4365 */ 4366 if (unlikely(tcpu != next_cpu) && 4367 (tcpu >= nr_cpu_ids || !cpu_online(tcpu) || 4368 ((int)(per_cpu(softnet_data, tcpu).input_queue_head - 4369 rflow->last_qtail)) >= 0)) { 4370 tcpu = next_cpu; 4371 rflow = set_rps_cpu(dev, skb, rflow, next_cpu); 4372 } 4373 4374 if (tcpu < nr_cpu_ids && cpu_online(tcpu)) { 4375 *rflowp = rflow; 4376 cpu = tcpu; 4377 goto done; 4378 } 4379 } 4380 4381 try_rps: 4382 4383 if (map) { 4384 tcpu = map->cpus[reciprocal_scale(hash, map->len)]; 4385 if (cpu_online(tcpu)) { 4386 cpu = tcpu; 4387 goto done; 4388 } 4389 } 4390 4391 done: 4392 return cpu; 4393 } 4394 4395 #ifdef CONFIG_RFS_ACCEL 4396 4397 /** 4398 * rps_may_expire_flow - check whether an RFS hardware filter may be removed 4399 * @dev: Device on which the filter was set 4400 * @rxq_index: RX queue index 4401 * @flow_id: Flow ID passed to ndo_rx_flow_steer() 4402 * @filter_id: Filter ID returned by ndo_rx_flow_steer() 4403 * 4404 * Drivers that implement ndo_rx_flow_steer() should periodically call 4405 * this function for each installed filter and remove the filters for 4406 * which it returns %true. 4407 */ 4408 bool rps_may_expire_flow(struct net_device *dev, u16 rxq_index, 4409 u32 flow_id, u16 filter_id) 4410 { 4411 struct netdev_rx_queue *rxqueue = dev->_rx + rxq_index; 4412 struct rps_dev_flow_table *flow_table; 4413 struct rps_dev_flow *rflow; 4414 bool expire = true; 4415 unsigned int cpu; 4416 4417 rcu_read_lock(); 4418 flow_table = rcu_dereference(rxqueue->rps_flow_table); 4419 if (flow_table && flow_id <= flow_table->mask) { 4420 rflow = &flow_table->flows[flow_id]; 4421 cpu = READ_ONCE(rflow->cpu); 4422 if (rflow->filter == filter_id && cpu < nr_cpu_ids && 4423 ((int)(per_cpu(softnet_data, cpu).input_queue_head - 4424 rflow->last_qtail) < 4425 (int)(10 * flow_table->mask))) 4426 expire = false; 4427 } 4428 rcu_read_unlock(); 4429 return expire; 4430 } 4431 EXPORT_SYMBOL(rps_may_expire_flow); 4432 4433 #endif /* CONFIG_RFS_ACCEL */ 4434 4435 /* Called from hardirq (IPI) context */ 4436 static void rps_trigger_softirq(void *data) 4437 { 4438 struct softnet_data *sd = data; 4439 4440 ____napi_schedule(sd, &sd->backlog); 4441 sd->received_rps++; 4442 } 4443 4444 #endif /* CONFIG_RPS */ 4445 4446 /* 4447 * Check if this softnet_data structure is another cpu one 4448 * If yes, queue it to our IPI list and return 1 4449 * If no, return 0 4450 */ 4451 static int rps_ipi_queued(struct softnet_data *sd) 4452 { 4453 #ifdef CONFIG_RPS 4454 struct softnet_data *mysd = this_cpu_ptr(&softnet_data); 4455 4456 if (sd != mysd) { 4457 sd->rps_ipi_next = mysd->rps_ipi_list; 4458 mysd->rps_ipi_list = sd; 4459 4460 __raise_softirq_irqoff(NET_RX_SOFTIRQ); 4461 return 1; 4462 } 4463 #endif /* CONFIG_RPS */ 4464 return 0; 4465 } 4466 4467 #ifdef CONFIG_NET_FLOW_LIMIT 4468 int netdev_flow_limit_table_len __read_mostly = (1 << 12); 4469 #endif 4470 4471 static bool skb_flow_limit(struct sk_buff *skb, unsigned int qlen) 4472 { 4473 #ifdef CONFIG_NET_FLOW_LIMIT 4474 struct sd_flow_limit *fl; 4475 struct softnet_data *sd; 4476 unsigned int old_flow, new_flow; 4477 4478 if (qlen < (netdev_max_backlog >> 1)) 4479 return false; 4480 4481 sd = this_cpu_ptr(&softnet_data); 4482 4483 rcu_read_lock(); 4484 fl = rcu_dereference(sd->flow_limit); 4485 if (fl) { 4486 new_flow = skb_get_hash(skb) & (fl->num_buckets - 1); 4487 old_flow = fl->history[fl->history_head]; 4488 fl->history[fl->history_head] = new_flow; 4489 4490 fl->history_head++; 4491 fl->history_head &= FLOW_LIMIT_HISTORY - 1; 4492 4493 if (likely(fl->buckets[old_flow])) 4494 fl->buckets[old_flow]--; 4495 4496 if (++fl->buckets[new_flow] > (FLOW_LIMIT_HISTORY >> 1)) { 4497 fl->count++; 4498 rcu_read_unlock(); 4499 return true; 4500 } 4501 } 4502 rcu_read_unlock(); 4503 #endif 4504 return false; 4505 } 4506 4507 /* 4508 * enqueue_to_backlog is called to queue an skb to a per CPU backlog 4509 * queue (may be a remote CPU queue). 4510 */ 4511 static int enqueue_to_backlog(struct sk_buff *skb, int cpu, 4512 unsigned int *qtail) 4513 { 4514 struct softnet_data *sd; 4515 unsigned long flags; 4516 unsigned int qlen; 4517 4518 sd = &per_cpu(softnet_data, cpu); 4519 4520 local_irq_save(flags); 4521 4522 rps_lock(sd); 4523 if (!netif_running(skb->dev)) 4524 goto drop; 4525 qlen = skb_queue_len(&sd->input_pkt_queue); 4526 if (qlen <= netdev_max_backlog && !skb_flow_limit(skb, qlen)) { 4527 if (qlen) { 4528 enqueue: 4529 __skb_queue_tail(&sd->input_pkt_queue, skb); 4530 input_queue_tail_incr_save(sd, qtail); 4531 rps_unlock(sd); 4532 local_irq_restore(flags); 4533 return NET_RX_SUCCESS; 4534 } 4535 4536 /* Schedule NAPI for backlog device 4537 * We can use non atomic operation since we own the queue lock 4538 */ 4539 if (!__test_and_set_bit(NAPI_STATE_SCHED, &sd->backlog.state)) { 4540 if (!rps_ipi_queued(sd)) 4541 ____napi_schedule(sd, &sd->backlog); 4542 } 4543 goto enqueue; 4544 } 4545 4546 drop: 4547 sd->dropped++; 4548 rps_unlock(sd); 4549 4550 local_irq_restore(flags); 4551 4552 atomic_long_inc(&skb->dev->rx_dropped); 4553 kfree_skb(skb); 4554 return NET_RX_DROP; 4555 } 4556 4557 static struct netdev_rx_queue *netif_get_rxqueue(struct sk_buff *skb) 4558 { 4559 struct net_device *dev = skb->dev; 4560 struct netdev_rx_queue *rxqueue; 4561 4562 rxqueue = dev->_rx; 4563 4564 if (skb_rx_queue_recorded(skb)) { 4565 u16 index = skb_get_rx_queue(skb); 4566 4567 if (unlikely(index >= dev->real_num_rx_queues)) { 4568 WARN_ONCE(dev->real_num_rx_queues > 1, 4569 "%s received packet on queue %u, but number " 4570 "of RX queues is %u\n", 4571 dev->name, index, dev->real_num_rx_queues); 4572 4573 return rxqueue; /* Return first rxqueue */ 4574 } 4575 rxqueue += index; 4576 } 4577 return rxqueue; 4578 } 4579 4580 u32 bpf_prog_run_generic_xdp(struct sk_buff *skb, struct xdp_buff *xdp, 4581 struct bpf_prog *xdp_prog) 4582 { 4583 void *orig_data, *orig_data_end, *hard_start; 4584 struct netdev_rx_queue *rxqueue; 4585 bool orig_bcast, orig_host; 4586 u32 mac_len, frame_sz; 4587 __be16 orig_eth_type; 4588 struct ethhdr *eth; 4589 u32 metalen, act; 4590 int off; 4591 4592 /* The XDP program wants to see the packet starting at the MAC 4593 * header. 4594 */ 4595 mac_len = skb->data - skb_mac_header(skb); 4596 hard_start = skb->data - skb_headroom(skb); 4597 4598 /* SKB "head" area always have tailroom for skb_shared_info */ 4599 frame_sz = (void *)skb_end_pointer(skb) - hard_start; 4600 frame_sz += SKB_DATA_ALIGN(sizeof(struct skb_shared_info)); 4601 4602 rxqueue = netif_get_rxqueue(skb); 4603 xdp_init_buff(xdp, frame_sz, &rxqueue->xdp_rxq); 4604 xdp_prepare_buff(xdp, hard_start, skb_headroom(skb) - mac_len, 4605 skb_headlen(skb) + mac_len, true); 4606 4607 orig_data_end = xdp->data_end; 4608 orig_data = xdp->data; 4609 eth = (struct ethhdr *)xdp->data; 4610 orig_host = ether_addr_equal_64bits(eth->h_dest, skb->dev->dev_addr); 4611 orig_bcast = is_multicast_ether_addr_64bits(eth->h_dest); 4612 orig_eth_type = eth->h_proto; 4613 4614 act = bpf_prog_run_xdp(xdp_prog, xdp); 4615 4616 /* check if bpf_xdp_adjust_head was used */ 4617 off = xdp->data - orig_data; 4618 if (off) { 4619 if (off > 0) 4620 __skb_pull(skb, off); 4621 else if (off < 0) 4622 __skb_push(skb, -off); 4623 4624 skb->mac_header += off; 4625 skb_reset_network_header(skb); 4626 } 4627 4628 /* check if bpf_xdp_adjust_tail was used */ 4629 off = xdp->data_end - orig_data_end; 4630 if (off != 0) { 4631 skb_set_tail_pointer(skb, xdp->data_end - xdp->data); 4632 skb->len += off; /* positive on grow, negative on shrink */ 4633 } 4634 4635 /* check if XDP changed eth hdr such SKB needs update */ 4636 eth = (struct ethhdr *)xdp->data; 4637 if ((orig_eth_type != eth->h_proto) || 4638 (orig_host != ether_addr_equal_64bits(eth->h_dest, 4639 skb->dev->dev_addr)) || 4640 (orig_bcast != is_multicast_ether_addr_64bits(eth->h_dest))) { 4641 __skb_push(skb, ETH_HLEN); 4642 skb->pkt_type = PACKET_HOST; 4643 skb->protocol = eth_type_trans(skb, skb->dev); 4644 } 4645 4646 /* Redirect/Tx gives L2 packet, code that will reuse skb must __skb_pull 4647 * before calling us again on redirect path. We do not call do_redirect 4648 * as we leave that up to the caller. 4649 * 4650 * Caller is responsible for managing lifetime of skb (i.e. calling 4651 * kfree_skb in response to actions it cannot handle/XDP_DROP). 4652 */ 4653 switch (act) { 4654 case XDP_REDIRECT: 4655 case XDP_TX: 4656 __skb_push(skb, mac_len); 4657 break; 4658 case XDP_PASS: 4659 metalen = xdp->data - xdp->data_meta; 4660 if (metalen) 4661 skb_metadata_set(skb, metalen); 4662 break; 4663 } 4664 4665 return act; 4666 } 4667 4668 static u32 netif_receive_generic_xdp(struct sk_buff *skb, 4669 struct xdp_buff *xdp, 4670 struct bpf_prog *xdp_prog) 4671 { 4672 u32 act = XDP_DROP; 4673 4674 /* Reinjected packets coming from act_mirred or similar should 4675 * not get XDP generic processing. 4676 */ 4677 if (skb_is_redirected(skb)) 4678 return XDP_PASS; 4679 4680 /* XDP packets must be linear and must have sufficient headroom 4681 * of XDP_PACKET_HEADROOM bytes. This is the guarantee that also 4682 * native XDP provides, thus we need to do it here as well. 4683 */ 4684 if (skb_cloned(skb) || skb_is_nonlinear(skb) || 4685 skb_headroom(skb) < XDP_PACKET_HEADROOM) { 4686 int hroom = XDP_PACKET_HEADROOM - skb_headroom(skb); 4687 int troom = skb->tail + skb->data_len - skb->end; 4688 4689 /* In case we have to go down the path and also linearize, 4690 * then lets do the pskb_expand_head() work just once here. 4691 */ 4692 if (pskb_expand_head(skb, 4693 hroom > 0 ? ALIGN(hroom, NET_SKB_PAD) : 0, 4694 troom > 0 ? troom + 128 : 0, GFP_ATOMIC)) 4695 goto do_drop; 4696 if (skb_linearize(skb)) 4697 goto do_drop; 4698 } 4699 4700 act = bpf_prog_run_generic_xdp(skb, xdp, xdp_prog); 4701 switch (act) { 4702 case XDP_REDIRECT: 4703 case XDP_TX: 4704 case XDP_PASS: 4705 break; 4706 default: 4707 bpf_warn_invalid_xdp_action(act); 4708 fallthrough; 4709 case XDP_ABORTED: 4710 trace_xdp_exception(skb->dev, xdp_prog, act); 4711 fallthrough; 4712 case XDP_DROP: 4713 do_drop: 4714 kfree_skb(skb); 4715 break; 4716 } 4717 4718 return act; 4719 } 4720 4721 /* When doing generic XDP we have to bypass the qdisc layer and the 4722 * network taps in order to match in-driver-XDP behavior. 4723 */ 4724 void generic_xdp_tx(struct sk_buff *skb, struct bpf_prog *xdp_prog) 4725 { 4726 struct net_device *dev = skb->dev; 4727 struct netdev_queue *txq; 4728 bool free_skb = true; 4729 int cpu, rc; 4730 4731 txq = netdev_core_pick_tx(dev, skb, NULL); 4732 cpu = smp_processor_id(); 4733 HARD_TX_LOCK(dev, txq, cpu); 4734 if (!netif_xmit_stopped(txq)) { 4735 rc = netdev_start_xmit(skb, dev, txq, 0); 4736 if (dev_xmit_complete(rc)) 4737 free_skb = false; 4738 } 4739 HARD_TX_UNLOCK(dev, txq); 4740 if (free_skb) { 4741 trace_xdp_exception(dev, xdp_prog, XDP_TX); 4742 kfree_skb(skb); 4743 } 4744 } 4745 4746 static DEFINE_STATIC_KEY_FALSE(generic_xdp_needed_key); 4747 4748 int do_xdp_generic(struct bpf_prog *xdp_prog, struct sk_buff *skb) 4749 { 4750 if (xdp_prog) { 4751 struct xdp_buff xdp; 4752 u32 act; 4753 int err; 4754 4755 act = netif_receive_generic_xdp(skb, &xdp, xdp_prog); 4756 if (act != XDP_PASS) { 4757 switch (act) { 4758 case XDP_REDIRECT: 4759 err = xdp_do_generic_redirect(skb->dev, skb, 4760 &xdp, xdp_prog); 4761 if (err) 4762 goto out_redir; 4763 break; 4764 case XDP_TX: 4765 generic_xdp_tx(skb, xdp_prog); 4766 break; 4767 } 4768 return XDP_DROP; 4769 } 4770 } 4771 return XDP_PASS; 4772 out_redir: 4773 kfree_skb(skb); 4774 return XDP_DROP; 4775 } 4776 EXPORT_SYMBOL_GPL(do_xdp_generic); 4777 4778 static int netif_rx_internal(struct sk_buff *skb) 4779 { 4780 int ret; 4781 4782 net_timestamp_check(netdev_tstamp_prequeue, skb); 4783 4784 trace_netif_rx(skb); 4785 4786 #ifdef CONFIG_RPS 4787 if (static_branch_unlikely(&rps_needed)) { 4788 struct rps_dev_flow voidflow, *rflow = &voidflow; 4789 int cpu; 4790 4791 preempt_disable(); 4792 rcu_read_lock(); 4793 4794 cpu = get_rps_cpu(skb->dev, skb, &rflow); 4795 if (cpu < 0) 4796 cpu = smp_processor_id(); 4797 4798 ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail); 4799 4800 rcu_read_unlock(); 4801 preempt_enable(); 4802 } else 4803 #endif 4804 { 4805 unsigned int qtail; 4806 4807 ret = enqueue_to_backlog(skb, get_cpu(), &qtail); 4808 put_cpu(); 4809 } 4810 return ret; 4811 } 4812 4813 /** 4814 * netif_rx - post buffer to the network code 4815 * @skb: buffer to post 4816 * 4817 * This function receives a packet from a device driver and queues it for 4818 * the upper (protocol) levels to process. It always succeeds. The buffer 4819 * may be dropped during processing for congestion control or by the 4820 * protocol layers. 4821 * 4822 * return values: 4823 * NET_RX_SUCCESS (no congestion) 4824 * NET_RX_DROP (packet was dropped) 4825 * 4826 */ 4827 4828 int netif_rx(struct sk_buff *skb) 4829 { 4830 int ret; 4831 4832 trace_netif_rx_entry(skb); 4833 4834 ret = netif_rx_internal(skb); 4835 trace_netif_rx_exit(ret); 4836 4837 return ret; 4838 } 4839 EXPORT_SYMBOL(netif_rx); 4840 4841 int netif_rx_ni(struct sk_buff *skb) 4842 { 4843 int err; 4844 4845 trace_netif_rx_ni_entry(skb); 4846 4847 preempt_disable(); 4848 err = netif_rx_internal(skb); 4849 if (local_softirq_pending()) 4850 do_softirq(); 4851 preempt_enable(); 4852 trace_netif_rx_ni_exit(err); 4853 4854 return err; 4855 } 4856 EXPORT_SYMBOL(netif_rx_ni); 4857 4858 int netif_rx_any_context(struct sk_buff *skb) 4859 { 4860 /* 4861 * If invoked from contexts which do not invoke bottom half 4862 * processing either at return from interrupt or when softrqs are 4863 * reenabled, use netif_rx_ni() which invokes bottomhalf processing 4864 * directly. 4865 */ 4866 if (in_interrupt()) 4867 return netif_rx(skb); 4868 else 4869 return netif_rx_ni(skb); 4870 } 4871 EXPORT_SYMBOL(netif_rx_any_context); 4872 4873 static __latent_entropy void net_tx_action(struct softirq_action *h) 4874 { 4875 struct softnet_data *sd = this_cpu_ptr(&softnet_data); 4876 4877 if (sd->completion_queue) { 4878 struct sk_buff *clist; 4879 4880 local_irq_disable(); 4881 clist = sd->completion_queue; 4882 sd->completion_queue = NULL; 4883 local_irq_enable(); 4884 4885 while (clist) { 4886 struct sk_buff *skb = clist; 4887 4888 clist = clist->next; 4889 4890 WARN_ON(refcount_read(&skb->users)); 4891 if (likely(get_kfree_skb_cb(skb)->reason == SKB_REASON_CONSUMED)) 4892 trace_consume_skb(skb); 4893 else 4894 trace_kfree_skb(skb, net_tx_action); 4895 4896 if (skb->fclone != SKB_FCLONE_UNAVAILABLE) 4897 __kfree_skb(skb); 4898 else 4899 __kfree_skb_defer(skb); 4900 } 4901 } 4902 4903 if (sd->output_queue) { 4904 struct Qdisc *head; 4905 4906 local_irq_disable(); 4907 head = sd->output_queue; 4908 sd->output_queue = NULL; 4909 sd->output_queue_tailp = &sd->output_queue; 4910 local_irq_enable(); 4911 4912 rcu_read_lock(); 4913 4914 while (head) { 4915 struct Qdisc *q = head; 4916 spinlock_t *root_lock = NULL; 4917 4918 head = head->next_sched; 4919 4920 /* We need to make sure head->next_sched is read 4921 * before clearing __QDISC_STATE_SCHED 4922 */ 4923 smp_mb__before_atomic(); 4924 4925 if (!(q->flags & TCQ_F_NOLOCK)) { 4926 root_lock = qdisc_lock(q); 4927 spin_lock(root_lock); 4928 } else if (unlikely(test_bit(__QDISC_STATE_DEACTIVATED, 4929 &q->state))) { 4930 /* There is a synchronize_net() between 4931 * STATE_DEACTIVATED flag being set and 4932 * qdisc_reset()/some_qdisc_is_busy() in 4933 * dev_deactivate(), so we can safely bail out 4934 * early here to avoid data race between 4935 * qdisc_deactivate() and some_qdisc_is_busy() 4936 * for lockless qdisc. 4937 */ 4938 clear_bit(__QDISC_STATE_SCHED, &q->state); 4939 continue; 4940 } 4941 4942 clear_bit(__QDISC_STATE_SCHED, &q->state); 4943 qdisc_run(q); 4944 if (root_lock) 4945 spin_unlock(root_lock); 4946 } 4947 4948 rcu_read_unlock(); 4949 } 4950 4951 xfrm_dev_backlog(sd); 4952 } 4953 4954 #if IS_ENABLED(CONFIG_BRIDGE) && IS_ENABLED(CONFIG_ATM_LANE) 4955 /* This hook is defined here for ATM LANE */ 4956 int (*br_fdb_test_addr_hook)(struct net_device *dev, 4957 unsigned char *addr) __read_mostly; 4958 EXPORT_SYMBOL_GPL(br_fdb_test_addr_hook); 4959 #endif 4960 4961 static inline struct sk_buff * 4962 sch_handle_ingress(struct sk_buff *skb, struct packet_type **pt_prev, int *ret, 4963 struct net_device *orig_dev, bool *another) 4964 { 4965 #ifdef CONFIG_NET_CLS_ACT 4966 struct mini_Qdisc *miniq = rcu_dereference_bh(skb->dev->miniq_ingress); 4967 struct tcf_result cl_res; 4968 4969 /* If there's at least one ingress present somewhere (so 4970 * we get here via enabled static key), remaining devices 4971 * that are not configured with an ingress qdisc will bail 4972 * out here. 4973 */ 4974 if (!miniq) 4975 return skb; 4976 4977 if (*pt_prev) { 4978 *ret = deliver_skb(skb, *pt_prev, orig_dev); 4979 *pt_prev = NULL; 4980 } 4981 4982 qdisc_skb_cb(skb)->pkt_len = skb->len; 4983 qdisc_skb_cb(skb)->mru = 0; 4984 qdisc_skb_cb(skb)->post_ct = false; 4985 skb->tc_at_ingress = 1; 4986 mini_qdisc_bstats_cpu_update(miniq, skb); 4987 4988 switch (tcf_classify(skb, miniq->block, miniq->filter_list, &cl_res, false)) { 4989 case TC_ACT_OK: 4990 case TC_ACT_RECLASSIFY: 4991 skb->tc_index = TC_H_MIN(cl_res.classid); 4992 break; 4993 case TC_ACT_SHOT: 4994 mini_qdisc_qstats_cpu_drop(miniq); 4995 kfree_skb(skb); 4996 return NULL; 4997 case TC_ACT_STOLEN: 4998 case TC_ACT_QUEUED: 4999 case TC_ACT_TRAP: 5000 consume_skb(skb); 5001 return NULL; 5002 case TC_ACT_REDIRECT: 5003 /* skb_mac_header check was done by cls/act_bpf, so 5004 * we can safely push the L2 header back before 5005 * redirecting to another netdev 5006 */ 5007 __skb_push(skb, skb->mac_len); 5008 if (skb_do_redirect(skb) == -EAGAIN) { 5009 __skb_pull(skb, skb->mac_len); 5010 *another = true; 5011 break; 5012 } 5013 return NULL; 5014 case TC_ACT_CONSUMED: 5015 return NULL; 5016 default: 5017 break; 5018 } 5019 #endif /* CONFIG_NET_CLS_ACT */ 5020 return skb; 5021 } 5022 5023 /** 5024 * netdev_is_rx_handler_busy - check if receive handler is registered 5025 * @dev: device to check 5026 * 5027 * Check if a receive handler is already registered for a given device. 5028 * Return true if there one. 5029 * 5030 * The caller must hold the rtnl_mutex. 5031 */ 5032 bool netdev_is_rx_handler_busy(struct net_device *dev) 5033 { 5034 ASSERT_RTNL(); 5035 return dev && rtnl_dereference(dev->rx_handler); 5036 } 5037 EXPORT_SYMBOL_GPL(netdev_is_rx_handler_busy); 5038 5039 /** 5040 * netdev_rx_handler_register - register receive handler 5041 * @dev: device to register a handler for 5042 * @rx_handler: receive handler to register 5043 * @rx_handler_data: data pointer that is used by rx handler 5044 * 5045 * Register a receive handler for a device. This handler will then be 5046 * called from __netif_receive_skb. A negative errno code is returned 5047 * on a failure. 5048 * 5049 * The caller must hold the rtnl_mutex. 5050 * 5051 * For a general description of rx_handler, see enum rx_handler_result. 5052 */ 5053 int netdev_rx_handler_register(struct net_device *dev, 5054 rx_handler_func_t *rx_handler, 5055 void *rx_handler_data) 5056 { 5057 if (netdev_is_rx_handler_busy(dev)) 5058 return -EBUSY; 5059 5060 if (dev->priv_flags & IFF_NO_RX_HANDLER) 5061 return -EINVAL; 5062 5063 /* Note: rx_handler_data must be set before rx_handler */ 5064 rcu_assign_pointer(dev->rx_handler_data, rx_handler_data); 5065 rcu_assign_pointer(dev->rx_handler, rx_handler); 5066 5067 return 0; 5068 } 5069 EXPORT_SYMBOL_GPL(netdev_rx_handler_register); 5070 5071 /** 5072 * netdev_rx_handler_unregister - unregister receive handler 5073 * @dev: device to unregister a handler from 5074 * 5075 * Unregister a receive handler from a device. 5076 * 5077 * The caller must hold the rtnl_mutex. 5078 */ 5079 void netdev_rx_handler_unregister(struct net_device *dev) 5080 { 5081 5082 ASSERT_RTNL(); 5083 RCU_INIT_POINTER(dev->rx_handler, NULL); 5084 /* a reader seeing a non NULL rx_handler in a rcu_read_lock() 5085 * section has a guarantee to see a non NULL rx_handler_data 5086 * as well. 5087 */ 5088 synchronize_net(); 5089 RCU_INIT_POINTER(dev->rx_handler_data, NULL); 5090 } 5091 EXPORT_SYMBOL_GPL(netdev_rx_handler_unregister); 5092 5093 /* 5094 * Limit the use of PFMEMALLOC reserves to those protocols that implement 5095 * the special handling of PFMEMALLOC skbs. 5096 */ 5097 static bool skb_pfmemalloc_protocol(struct sk_buff *skb) 5098 { 5099 switch (skb->protocol) { 5100 case htons(ETH_P_ARP): 5101 case htons(ETH_P_IP): 5102 case htons(ETH_P_IPV6): 5103 case htons(ETH_P_8021Q): 5104 case htons(ETH_P_8021AD): 5105 return true; 5106 default: 5107 return false; 5108 } 5109 } 5110 5111 static inline int nf_ingress(struct sk_buff *skb, struct packet_type **pt_prev, 5112 int *ret, struct net_device *orig_dev) 5113 { 5114 if (nf_hook_ingress_active(skb)) { 5115 int ingress_retval; 5116 5117 if (*pt_prev) { 5118 *ret = deliver_skb(skb, *pt_prev, orig_dev); 5119 *pt_prev = NULL; 5120 } 5121 5122 rcu_read_lock(); 5123 ingress_retval = nf_hook_ingress(skb); 5124 rcu_read_unlock(); 5125 return ingress_retval; 5126 } 5127 return 0; 5128 } 5129 5130 static int __netif_receive_skb_core(struct sk_buff **pskb, bool pfmemalloc, 5131 struct packet_type **ppt_prev) 5132 { 5133 struct packet_type *ptype, *pt_prev; 5134 rx_handler_func_t *rx_handler; 5135 struct sk_buff *skb = *pskb; 5136 struct net_device *orig_dev; 5137 bool deliver_exact = false; 5138 int ret = NET_RX_DROP; 5139 __be16 type; 5140 5141 net_timestamp_check(!netdev_tstamp_prequeue, skb); 5142 5143 trace_netif_receive_skb(skb); 5144 5145 orig_dev = skb->dev; 5146 5147 skb_reset_network_header(skb); 5148 if (!skb_transport_header_was_set(skb)) 5149 skb_reset_transport_header(skb); 5150 skb_reset_mac_len(skb); 5151 5152 pt_prev = NULL; 5153 5154 another_round: 5155 skb->skb_iif = skb->dev->ifindex; 5156 5157 __this_cpu_inc(softnet_data.processed); 5158 5159 if (static_branch_unlikely(&generic_xdp_needed_key)) { 5160 int ret2; 5161 5162 migrate_disable(); 5163 ret2 = do_xdp_generic(rcu_dereference(skb->dev->xdp_prog), skb); 5164 migrate_enable(); 5165 5166 if (ret2 != XDP_PASS) { 5167 ret = NET_RX_DROP; 5168 goto out; 5169 } 5170 } 5171 5172 if (eth_type_vlan(skb->protocol)) { 5173 skb = skb_vlan_untag(skb); 5174 if (unlikely(!skb)) 5175 goto out; 5176 } 5177 5178 if (skb_skip_tc_classify(skb)) 5179 goto skip_classify; 5180 5181 if (pfmemalloc) 5182 goto skip_taps; 5183 5184 list_for_each_entry_rcu(ptype, &ptype_all, list) { 5185 if (pt_prev) 5186 ret = deliver_skb(skb, pt_prev, orig_dev); 5187 pt_prev = ptype; 5188 } 5189 5190 list_for_each_entry_rcu(ptype, &skb->dev->ptype_all, list) { 5191 if (pt_prev) 5192 ret = deliver_skb(skb, pt_prev, orig_dev); 5193 pt_prev = ptype; 5194 } 5195 5196 skip_taps: 5197 #ifdef CONFIG_NET_INGRESS 5198 if (static_branch_unlikely(&ingress_needed_key)) { 5199 bool another = false; 5200 5201 nf_skip_egress(skb, true); 5202 skb = sch_handle_ingress(skb, &pt_prev, &ret, orig_dev, 5203 &another); 5204 if (another) 5205 goto another_round; 5206 if (!skb) 5207 goto out; 5208 5209 nf_skip_egress(skb, false); 5210 if (nf_ingress(skb, &pt_prev, &ret, orig_dev) < 0) 5211 goto out; 5212 } 5213 #endif 5214 skb_reset_redirect(skb); 5215 skip_classify: 5216 if (pfmemalloc && !skb_pfmemalloc_protocol(skb)) 5217 goto drop; 5218 5219 if (skb_vlan_tag_present(skb)) { 5220 if (pt_prev) { 5221 ret = deliver_skb(skb, pt_prev, orig_dev); 5222 pt_prev = NULL; 5223 } 5224 if (vlan_do_receive(&skb)) 5225 goto another_round; 5226 else if (unlikely(!skb)) 5227 goto out; 5228 } 5229 5230 rx_handler = rcu_dereference(skb->dev->rx_handler); 5231 if (rx_handler) { 5232 if (pt_prev) { 5233 ret = deliver_skb(skb, pt_prev, orig_dev); 5234 pt_prev = NULL; 5235 } 5236 switch (rx_handler(&skb)) { 5237 case RX_HANDLER_CONSUMED: 5238 ret = NET_RX_SUCCESS; 5239 goto out; 5240 case RX_HANDLER_ANOTHER: 5241 goto another_round; 5242 case RX_HANDLER_EXACT: 5243 deliver_exact = true; 5244 break; 5245 case RX_HANDLER_PASS: 5246 break; 5247 default: 5248 BUG(); 5249 } 5250 } 5251 5252 if (unlikely(skb_vlan_tag_present(skb)) && !netdev_uses_dsa(skb->dev)) { 5253 check_vlan_id: 5254 if (skb_vlan_tag_get_id(skb)) { 5255 /* Vlan id is non 0 and vlan_do_receive() above couldn't 5256 * find vlan device. 5257 */ 5258 skb->pkt_type = PACKET_OTHERHOST; 5259 } else if (eth_type_vlan(skb->protocol)) { 5260 /* Outer header is 802.1P with vlan 0, inner header is 5261 * 802.1Q or 802.1AD and vlan_do_receive() above could 5262 * not find vlan dev for vlan id 0. 5263 */ 5264 __vlan_hwaccel_clear_tag(skb); 5265 skb = skb_vlan_untag(skb); 5266 if (unlikely(!skb)) 5267 goto out; 5268 if (vlan_do_receive(&skb)) 5269 /* After stripping off 802.1P header with vlan 0 5270 * vlan dev is found for inner header. 5271 */ 5272 goto another_round; 5273 else if (unlikely(!skb)) 5274 goto out; 5275 else 5276 /* We have stripped outer 802.1P vlan 0 header. 5277 * But could not find vlan dev. 5278 * check again for vlan id to set OTHERHOST. 5279 */ 5280 goto check_vlan_id; 5281 } 5282 /* Note: we might in the future use prio bits 5283 * and set skb->priority like in vlan_do_receive() 5284 * For the time being, just ignore Priority Code Point 5285 */ 5286 __vlan_hwaccel_clear_tag(skb); 5287 } 5288 5289 type = skb->protocol; 5290 5291 /* deliver only exact match when indicated */ 5292 if (likely(!deliver_exact)) { 5293 deliver_ptype_list_skb(skb, &pt_prev, orig_dev, type, 5294 &ptype_base[ntohs(type) & 5295 PTYPE_HASH_MASK]); 5296 } 5297 5298 deliver_ptype_list_skb(skb, &pt_prev, orig_dev, type, 5299 &orig_dev->ptype_specific); 5300 5301 if (unlikely(skb->dev != orig_dev)) { 5302 deliver_ptype_list_skb(skb, &pt_prev, orig_dev, type, 5303 &skb->dev->ptype_specific); 5304 } 5305 5306 if (pt_prev) { 5307 if (unlikely(skb_orphan_frags_rx(skb, GFP_ATOMIC))) 5308 goto drop; 5309 *ppt_prev = pt_prev; 5310 } else { 5311 drop: 5312 if (!deliver_exact) 5313 atomic_long_inc(&skb->dev->rx_dropped); 5314 else 5315 atomic_long_inc(&skb->dev->rx_nohandler); 5316 kfree_skb(skb); 5317 /* Jamal, now you will not able to escape explaining 5318 * me how you were going to use this. :-) 5319 */ 5320 ret = NET_RX_DROP; 5321 } 5322 5323 out: 5324 /* The invariant here is that if *ppt_prev is not NULL 5325 * then skb should also be non-NULL. 5326 * 5327 * Apparently *ppt_prev assignment above holds this invariant due to 5328 * skb dereferencing near it. 5329 */ 5330 *pskb = skb; 5331 return ret; 5332 } 5333 5334 static int __netif_receive_skb_one_core(struct sk_buff *skb, bool pfmemalloc) 5335 { 5336 struct net_device *orig_dev = skb->dev; 5337 struct packet_type *pt_prev = NULL; 5338 int ret; 5339 5340 ret = __netif_receive_skb_core(&skb, pfmemalloc, &pt_prev); 5341 if (pt_prev) 5342 ret = INDIRECT_CALL_INET(pt_prev->func, ipv6_rcv, ip_rcv, skb, 5343 skb->dev, pt_prev, orig_dev); 5344 return ret; 5345 } 5346 5347 /** 5348 * netif_receive_skb_core - special purpose version of netif_receive_skb 5349 * @skb: buffer to process 5350 * 5351 * More direct receive version of netif_receive_skb(). It should 5352 * only be used by callers that have a need to skip RPS and Generic XDP. 5353 * Caller must also take care of handling if ``(page_is_)pfmemalloc``. 5354 * 5355 * This function may only be called from softirq context and interrupts 5356 * should be enabled. 5357 * 5358 * Return values (usually ignored): 5359 * NET_RX_SUCCESS: no congestion 5360 * NET_RX_DROP: packet was dropped 5361 */ 5362 int netif_receive_skb_core(struct sk_buff *skb) 5363 { 5364 int ret; 5365 5366 rcu_read_lock(); 5367 ret = __netif_receive_skb_one_core(skb, false); 5368 rcu_read_unlock(); 5369 5370 return ret; 5371 } 5372 EXPORT_SYMBOL(netif_receive_skb_core); 5373 5374 static inline void __netif_receive_skb_list_ptype(struct list_head *head, 5375 struct packet_type *pt_prev, 5376 struct net_device *orig_dev) 5377 { 5378 struct sk_buff *skb, *next; 5379 5380 if (!pt_prev) 5381 return; 5382 if (list_empty(head)) 5383 return; 5384 if (pt_prev->list_func != NULL) 5385 INDIRECT_CALL_INET(pt_prev->list_func, ipv6_list_rcv, 5386 ip_list_rcv, head, pt_prev, orig_dev); 5387 else 5388 list_for_each_entry_safe(skb, next, head, list) { 5389 skb_list_del_init(skb); 5390 pt_prev->func(skb, skb->dev, pt_prev, orig_dev); 5391 } 5392 } 5393 5394 static void __netif_receive_skb_list_core(struct list_head *head, bool pfmemalloc) 5395 { 5396 /* Fast-path assumptions: 5397 * - There is no RX handler. 5398 * - Only one packet_type matches. 5399 * If either of these fails, we will end up doing some per-packet 5400 * processing in-line, then handling the 'last ptype' for the whole 5401 * sublist. This can't cause out-of-order delivery to any single ptype, 5402 * because the 'last ptype' must be constant across the sublist, and all 5403 * other ptypes are handled per-packet. 5404 */ 5405 /* Current (common) ptype of sublist */ 5406 struct packet_type *pt_curr = NULL; 5407 /* Current (common) orig_dev of sublist */ 5408 struct net_device *od_curr = NULL; 5409 struct list_head sublist; 5410 struct sk_buff *skb, *next; 5411 5412 INIT_LIST_HEAD(&sublist); 5413 list_for_each_entry_safe(skb, next, head, list) { 5414 struct net_device *orig_dev = skb->dev; 5415 struct packet_type *pt_prev = NULL; 5416 5417 skb_list_del_init(skb); 5418 __netif_receive_skb_core(&skb, pfmemalloc, &pt_prev); 5419 if (!pt_prev) 5420 continue; 5421 if (pt_curr != pt_prev || od_curr != orig_dev) { 5422 /* dispatch old sublist */ 5423 __netif_receive_skb_list_ptype(&sublist, pt_curr, od_curr); 5424 /* start new sublist */ 5425 INIT_LIST_HEAD(&sublist); 5426 pt_curr = pt_prev; 5427 od_curr = orig_dev; 5428 } 5429 list_add_tail(&skb->list, &sublist); 5430 } 5431 5432 /* dispatch final sublist */ 5433 __netif_receive_skb_list_ptype(&sublist, pt_curr, od_curr); 5434 } 5435 5436 static int __netif_receive_skb(struct sk_buff *skb) 5437 { 5438 int ret; 5439 5440 if (sk_memalloc_socks() && skb_pfmemalloc(skb)) { 5441 unsigned int noreclaim_flag; 5442 5443 /* 5444 * PFMEMALLOC skbs are special, they should 5445 * - be delivered to SOCK_MEMALLOC sockets only 5446 * - stay away from userspace 5447 * - have bounded memory usage 5448 * 5449 * Use PF_MEMALLOC as this saves us from propagating the allocation 5450 * context down to all allocation sites. 5451 */ 5452 noreclaim_flag = memalloc_noreclaim_save(); 5453 ret = __netif_receive_skb_one_core(skb, true); 5454 memalloc_noreclaim_restore(noreclaim_flag); 5455 } else 5456 ret = __netif_receive_skb_one_core(skb, false); 5457 5458 return ret; 5459 } 5460 5461 static void __netif_receive_skb_list(struct list_head *head) 5462 { 5463 unsigned long noreclaim_flag = 0; 5464 struct sk_buff *skb, *next; 5465 bool pfmemalloc = false; /* Is current sublist PF_MEMALLOC? */ 5466 5467 list_for_each_entry_safe(skb, next, head, list) { 5468 if ((sk_memalloc_socks() && skb_pfmemalloc(skb)) != pfmemalloc) { 5469 struct list_head sublist; 5470 5471 /* Handle the previous sublist */ 5472 list_cut_before(&sublist, head, &skb->list); 5473 if (!list_empty(&sublist)) 5474 __netif_receive_skb_list_core(&sublist, pfmemalloc); 5475 pfmemalloc = !pfmemalloc; 5476 /* See comments in __netif_receive_skb */ 5477 if (pfmemalloc) 5478 noreclaim_flag = memalloc_noreclaim_save(); 5479 else 5480 memalloc_noreclaim_restore(noreclaim_flag); 5481 } 5482 } 5483 /* Handle the remaining sublist */ 5484 if (!list_empty(head)) 5485 __netif_receive_skb_list_core(head, pfmemalloc); 5486 /* Restore pflags */ 5487 if (pfmemalloc) 5488 memalloc_noreclaim_restore(noreclaim_flag); 5489 } 5490 5491 static int generic_xdp_install(struct net_device *dev, struct netdev_bpf *xdp) 5492 { 5493 struct bpf_prog *old = rtnl_dereference(dev->xdp_prog); 5494 struct bpf_prog *new = xdp->prog; 5495 int ret = 0; 5496 5497 switch (xdp->command) { 5498 case XDP_SETUP_PROG: 5499 rcu_assign_pointer(dev->xdp_prog, new); 5500 if (old) 5501 bpf_prog_put(old); 5502 5503 if (old && !new) { 5504 static_branch_dec(&generic_xdp_needed_key); 5505 } else if (new && !old) { 5506 static_branch_inc(&generic_xdp_needed_key); 5507 dev_disable_lro(dev); 5508 dev_disable_gro_hw(dev); 5509 } 5510 break; 5511 5512 default: 5513 ret = -EINVAL; 5514 break; 5515 } 5516 5517 return ret; 5518 } 5519 5520 static int netif_receive_skb_internal(struct sk_buff *skb) 5521 { 5522 int ret; 5523 5524 net_timestamp_check(netdev_tstamp_prequeue, skb); 5525 5526 if (skb_defer_rx_timestamp(skb)) 5527 return NET_RX_SUCCESS; 5528 5529 rcu_read_lock(); 5530 #ifdef CONFIG_RPS 5531 if (static_branch_unlikely(&rps_needed)) { 5532 struct rps_dev_flow voidflow, *rflow = &voidflow; 5533 int cpu = get_rps_cpu(skb->dev, skb, &rflow); 5534 5535 if (cpu >= 0) { 5536 ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail); 5537 rcu_read_unlock(); 5538 return ret; 5539 } 5540 } 5541 #endif 5542 ret = __netif_receive_skb(skb); 5543 rcu_read_unlock(); 5544 return ret; 5545 } 5546 5547 void netif_receive_skb_list_internal(struct list_head *head) 5548 { 5549 struct sk_buff *skb, *next; 5550 struct list_head sublist; 5551 5552 INIT_LIST_HEAD(&sublist); 5553 list_for_each_entry_safe(skb, next, head, list) { 5554 net_timestamp_check(netdev_tstamp_prequeue, skb); 5555 skb_list_del_init(skb); 5556 if (!skb_defer_rx_timestamp(skb)) 5557 list_add_tail(&skb->list, &sublist); 5558 } 5559 list_splice_init(&sublist, head); 5560 5561 rcu_read_lock(); 5562 #ifdef CONFIG_RPS 5563 if (static_branch_unlikely(&rps_needed)) { 5564 list_for_each_entry_safe(skb, next, head, list) { 5565 struct rps_dev_flow voidflow, *rflow = &voidflow; 5566 int cpu = get_rps_cpu(skb->dev, skb, &rflow); 5567 5568 if (cpu >= 0) { 5569 /* Will be handled, remove from list */ 5570 skb_list_del_init(skb); 5571 enqueue_to_backlog(skb, cpu, &rflow->last_qtail); 5572 } 5573 } 5574 } 5575 #endif 5576 __netif_receive_skb_list(head); 5577 rcu_read_unlock(); 5578 } 5579 5580 /** 5581 * netif_receive_skb - process receive buffer from network 5582 * @skb: buffer to process 5583 * 5584 * netif_receive_skb() is the main receive data processing function. 5585 * It always succeeds. The buffer may be dropped during processing 5586 * for congestion control or by the protocol layers. 5587 * 5588 * This function may only be called from softirq context and interrupts 5589 * should be enabled. 5590 * 5591 * Return values (usually ignored): 5592 * NET_RX_SUCCESS: no congestion 5593 * NET_RX_DROP: packet was dropped 5594 */ 5595 int netif_receive_skb(struct sk_buff *skb) 5596 { 5597 int ret; 5598 5599 trace_netif_receive_skb_entry(skb); 5600 5601 ret = netif_receive_skb_internal(skb); 5602 trace_netif_receive_skb_exit(ret); 5603 5604 return ret; 5605 } 5606 EXPORT_SYMBOL(netif_receive_skb); 5607 5608 /** 5609 * netif_receive_skb_list - process many receive buffers from network 5610 * @head: list of skbs to process. 5611 * 5612 * Since return value of netif_receive_skb() is normally ignored, and 5613 * wouldn't be meaningful for a list, this function returns void. 5614 * 5615 * This function may only be called from softirq context and interrupts 5616 * should be enabled. 5617 */ 5618 void netif_receive_skb_list(struct list_head *head) 5619 { 5620 struct sk_buff *skb; 5621 5622 if (list_empty(head)) 5623 return; 5624 if (trace_netif_receive_skb_list_entry_enabled()) { 5625 list_for_each_entry(skb, head, list) 5626 trace_netif_receive_skb_list_entry(skb); 5627 } 5628 netif_receive_skb_list_internal(head); 5629 trace_netif_receive_skb_list_exit(0); 5630 } 5631 EXPORT_SYMBOL(netif_receive_skb_list); 5632 5633 static DEFINE_PER_CPU(struct work_struct, flush_works); 5634 5635 /* Network device is going away, flush any packets still pending */ 5636 static void flush_backlog(struct work_struct *work) 5637 { 5638 struct sk_buff *skb, *tmp; 5639 struct softnet_data *sd; 5640 5641 local_bh_disable(); 5642 sd = this_cpu_ptr(&softnet_data); 5643 5644 local_irq_disable(); 5645 rps_lock(sd); 5646 skb_queue_walk_safe(&sd->input_pkt_queue, skb, tmp) { 5647 if (skb->dev->reg_state == NETREG_UNREGISTERING) { 5648 __skb_unlink(skb, &sd->input_pkt_queue); 5649 dev_kfree_skb_irq(skb); 5650 input_queue_head_incr(sd); 5651 } 5652 } 5653 rps_unlock(sd); 5654 local_irq_enable(); 5655 5656 skb_queue_walk_safe(&sd->process_queue, skb, tmp) { 5657 if (skb->dev->reg_state == NETREG_UNREGISTERING) { 5658 __skb_unlink(skb, &sd->process_queue); 5659 kfree_skb(skb); 5660 input_queue_head_incr(sd); 5661 } 5662 } 5663 local_bh_enable(); 5664 } 5665 5666 static bool flush_required(int cpu) 5667 { 5668 #if IS_ENABLED(CONFIG_RPS) 5669 struct softnet_data *sd = &per_cpu(softnet_data, cpu); 5670 bool do_flush; 5671 5672 local_irq_disable(); 5673 rps_lock(sd); 5674 5675 /* as insertion into process_queue happens with the rps lock held, 5676 * process_queue access may race only with dequeue 5677 */ 5678 do_flush = !skb_queue_empty(&sd->input_pkt_queue) || 5679 !skb_queue_empty_lockless(&sd->process_queue); 5680 rps_unlock(sd); 5681 local_irq_enable(); 5682 5683 return do_flush; 5684 #endif 5685 /* without RPS we can't safely check input_pkt_queue: during a 5686 * concurrent remote skb_queue_splice() we can detect as empty both 5687 * input_pkt_queue and process_queue even if the latter could end-up 5688 * containing a lot of packets. 5689 */ 5690 return true; 5691 } 5692 5693 static void flush_all_backlogs(void) 5694 { 5695 static cpumask_t flush_cpus; 5696 unsigned int cpu; 5697 5698 /* since we are under rtnl lock protection we can use static data 5699 * for the cpumask and avoid allocating on stack the possibly 5700 * large mask 5701 */ 5702 ASSERT_RTNL(); 5703 5704 cpus_read_lock(); 5705 5706 cpumask_clear(&flush_cpus); 5707 for_each_online_cpu(cpu) { 5708 if (flush_required(cpu)) { 5709 queue_work_on(cpu, system_highpri_wq, 5710 per_cpu_ptr(&flush_works, cpu)); 5711 cpumask_set_cpu(cpu, &flush_cpus); 5712 } 5713 } 5714 5715 /* we can have in flight packet[s] on the cpus we are not flushing, 5716 * synchronize_net() in unregister_netdevice_many() will take care of 5717 * them 5718 */ 5719 for_each_cpu(cpu, &flush_cpus) 5720 flush_work(per_cpu_ptr(&flush_works, cpu)); 5721 5722 cpus_read_unlock(); 5723 } 5724 5725 static void net_rps_send_ipi(struct softnet_data *remsd) 5726 { 5727 #ifdef CONFIG_RPS 5728 while (remsd) { 5729 struct softnet_data *next = remsd->rps_ipi_next; 5730 5731 if (cpu_online(remsd->cpu)) 5732 smp_call_function_single_async(remsd->cpu, &remsd->csd); 5733 remsd = next; 5734 } 5735 #endif 5736 } 5737 5738 /* 5739 * net_rps_action_and_irq_enable sends any pending IPI's for rps. 5740 * Note: called with local irq disabled, but exits with local irq enabled. 5741 */ 5742 static void net_rps_action_and_irq_enable(struct softnet_data *sd) 5743 { 5744 #ifdef CONFIG_RPS 5745 struct softnet_data *remsd = sd->rps_ipi_list; 5746 5747 if (remsd) { 5748 sd->rps_ipi_list = NULL; 5749 5750 local_irq_enable(); 5751 5752 /* Send pending IPI's to kick RPS processing on remote cpus. */ 5753 net_rps_send_ipi(remsd); 5754 } else 5755 #endif 5756 local_irq_enable(); 5757 } 5758 5759 static bool sd_has_rps_ipi_waiting(struct softnet_data *sd) 5760 { 5761 #ifdef CONFIG_RPS 5762 return sd->rps_ipi_list != NULL; 5763 #else 5764 return false; 5765 #endif 5766 } 5767 5768 static int process_backlog(struct napi_struct *napi, int quota) 5769 { 5770 struct softnet_data *sd = container_of(napi, struct softnet_data, backlog); 5771 bool again = true; 5772 int work = 0; 5773 5774 /* Check if we have pending ipi, its better to send them now, 5775 * not waiting net_rx_action() end. 5776 */ 5777 if (sd_has_rps_ipi_waiting(sd)) { 5778 local_irq_disable(); 5779 net_rps_action_and_irq_enable(sd); 5780 } 5781 5782 napi->weight = dev_rx_weight; 5783 while (again) { 5784 struct sk_buff *skb; 5785 5786 while ((skb = __skb_dequeue(&sd->process_queue))) { 5787 rcu_read_lock(); 5788 __netif_receive_skb(skb); 5789 rcu_read_unlock(); 5790 input_queue_head_incr(sd); 5791 if (++work >= quota) 5792 return work; 5793 5794 } 5795 5796 local_irq_disable(); 5797 rps_lock(sd); 5798 if (skb_queue_empty(&sd->input_pkt_queue)) { 5799 /* 5800 * Inline a custom version of __napi_complete(). 5801 * only current cpu owns and manipulates this napi, 5802 * and NAPI_STATE_SCHED is the only possible flag set 5803 * on backlog. 5804 * We can use a plain write instead of clear_bit(), 5805 * and we dont need an smp_mb() memory barrier. 5806 */ 5807 napi->state = 0; 5808 again = false; 5809 } else { 5810 skb_queue_splice_tail_init(&sd->input_pkt_queue, 5811 &sd->process_queue); 5812 } 5813 rps_unlock(sd); 5814 local_irq_enable(); 5815 } 5816 5817 return work; 5818 } 5819 5820 /** 5821 * __napi_schedule - schedule for receive 5822 * @n: entry to schedule 5823 * 5824 * The entry's receive function will be scheduled to run. 5825 * Consider using __napi_schedule_irqoff() if hard irqs are masked. 5826 */ 5827 void __napi_schedule(struct napi_struct *n) 5828 { 5829 unsigned long flags; 5830 5831 local_irq_save(flags); 5832 ____napi_schedule(this_cpu_ptr(&softnet_data), n); 5833 local_irq_restore(flags); 5834 } 5835 EXPORT_SYMBOL(__napi_schedule); 5836 5837 /** 5838 * napi_schedule_prep - check if napi can be scheduled 5839 * @n: napi context 5840 * 5841 * Test if NAPI routine is already running, and if not mark 5842 * it as running. This is used as a condition variable to 5843 * insure only one NAPI poll instance runs. We also make 5844 * sure there is no pending NAPI disable. 5845 */ 5846 bool napi_schedule_prep(struct napi_struct *n) 5847 { 5848 unsigned long val, new; 5849 5850 do { 5851 val = READ_ONCE(n->state); 5852 if (unlikely(val & NAPIF_STATE_DISABLE)) 5853 return false; 5854 new = val | NAPIF_STATE_SCHED; 5855 5856 /* Sets STATE_MISSED bit if STATE_SCHED was already set 5857 * This was suggested by Alexander Duyck, as compiler 5858 * emits better code than : 5859 * if (val & NAPIF_STATE_SCHED) 5860 * new |= NAPIF_STATE_MISSED; 5861 */ 5862 new |= (val & NAPIF_STATE_SCHED) / NAPIF_STATE_SCHED * 5863 NAPIF_STATE_MISSED; 5864 } while (cmpxchg(&n->state, val, new) != val); 5865 5866 return !(val & NAPIF_STATE_SCHED); 5867 } 5868 EXPORT_SYMBOL(napi_schedule_prep); 5869 5870 /** 5871 * __napi_schedule_irqoff - schedule for receive 5872 * @n: entry to schedule 5873 * 5874 * Variant of __napi_schedule() assuming hard irqs are masked. 5875 * 5876 * On PREEMPT_RT enabled kernels this maps to __napi_schedule() 5877 * because the interrupt disabled assumption might not be true 5878 * due to force-threaded interrupts and spinlock substitution. 5879 */ 5880 void __napi_schedule_irqoff(struct napi_struct *n) 5881 { 5882 if (!IS_ENABLED(CONFIG_PREEMPT_RT)) 5883 ____napi_schedule(this_cpu_ptr(&softnet_data), n); 5884 else 5885 __napi_schedule(n); 5886 } 5887 EXPORT_SYMBOL(__napi_schedule_irqoff); 5888 5889 bool napi_complete_done(struct napi_struct *n, int work_done) 5890 { 5891 unsigned long flags, val, new, timeout = 0; 5892 bool ret = true; 5893 5894 /* 5895 * 1) Don't let napi dequeue from the cpu poll list 5896 * just in case its running on a different cpu. 5897 * 2) If we are busy polling, do nothing here, we have 5898 * the guarantee we will be called later. 5899 */ 5900 if (unlikely(n->state & (NAPIF_STATE_NPSVC | 5901 NAPIF_STATE_IN_BUSY_POLL))) 5902 return false; 5903 5904 if (work_done) { 5905 if (n->gro_bitmask) 5906 timeout = READ_ONCE(n->dev->gro_flush_timeout); 5907 n->defer_hard_irqs_count = READ_ONCE(n->dev->napi_defer_hard_irqs); 5908 } 5909 if (n->defer_hard_irqs_count > 0) { 5910 n->defer_hard_irqs_count--; 5911 timeout = READ_ONCE(n->dev->gro_flush_timeout); 5912 if (timeout) 5913 ret = false; 5914 } 5915 if (n->gro_bitmask) { 5916 /* When the NAPI instance uses a timeout and keeps postponing 5917 * it, we need to bound somehow the time packets are kept in 5918 * the GRO layer 5919 */ 5920 napi_gro_flush(n, !!timeout); 5921 } 5922 5923 gro_normal_list(n); 5924 5925 if (unlikely(!list_empty(&n->poll_list))) { 5926 /* If n->poll_list is not empty, we need to mask irqs */ 5927 local_irq_save(flags); 5928 list_del_init(&n->poll_list); 5929 local_irq_restore(flags); 5930 } 5931 5932 do { 5933 val = READ_ONCE(n->state); 5934 5935 WARN_ON_ONCE(!(val & NAPIF_STATE_SCHED)); 5936 5937 new = val & ~(NAPIF_STATE_MISSED | NAPIF_STATE_SCHED | 5938 NAPIF_STATE_SCHED_THREADED | 5939 NAPIF_STATE_PREFER_BUSY_POLL); 5940 5941 /* If STATE_MISSED was set, leave STATE_SCHED set, 5942 * because we will call napi->poll() one more time. 5943 * This C code was suggested by Alexander Duyck to help gcc. 5944 */ 5945 new |= (val & NAPIF_STATE_MISSED) / NAPIF_STATE_MISSED * 5946 NAPIF_STATE_SCHED; 5947 } while (cmpxchg(&n->state, val, new) != val); 5948 5949 if (unlikely(val & NAPIF_STATE_MISSED)) { 5950 __napi_schedule(n); 5951 return false; 5952 } 5953 5954 if (timeout) 5955 hrtimer_start(&n->timer, ns_to_ktime(timeout), 5956 HRTIMER_MODE_REL_PINNED); 5957 return ret; 5958 } 5959 EXPORT_SYMBOL(napi_complete_done); 5960 5961 /* must be called under rcu_read_lock(), as we dont take a reference */ 5962 static struct napi_struct *napi_by_id(unsigned int napi_id) 5963 { 5964 unsigned int hash = napi_id % HASH_SIZE(napi_hash); 5965 struct napi_struct *napi; 5966 5967 hlist_for_each_entry_rcu(napi, &napi_hash[hash], napi_hash_node) 5968 if (napi->napi_id == napi_id) 5969 return napi; 5970 5971 return NULL; 5972 } 5973 5974 #if defined(CONFIG_NET_RX_BUSY_POLL) 5975 5976 static void __busy_poll_stop(struct napi_struct *napi, bool skip_schedule) 5977 { 5978 if (!skip_schedule) { 5979 gro_normal_list(napi); 5980 __napi_schedule(napi); 5981 return; 5982 } 5983 5984 if (napi->gro_bitmask) { 5985 /* flush too old packets 5986 * If HZ < 1000, flush all packets. 5987 */ 5988 napi_gro_flush(napi, HZ >= 1000); 5989 } 5990 5991 gro_normal_list(napi); 5992 clear_bit(NAPI_STATE_SCHED, &napi->state); 5993 } 5994 5995 static void busy_poll_stop(struct napi_struct *napi, void *have_poll_lock, bool prefer_busy_poll, 5996 u16 budget) 5997 { 5998 bool skip_schedule = false; 5999 unsigned long timeout; 6000 int rc; 6001 6002 /* Busy polling means there is a high chance device driver hard irq 6003 * could not grab NAPI_STATE_SCHED, and that NAPI_STATE_MISSED was 6004 * set in napi_schedule_prep(). 6005 * Since we are about to call napi->poll() once more, we can safely 6006 * clear NAPI_STATE_MISSED. 6007 * 6008 * Note: x86 could use a single "lock and ..." instruction 6009 * to perform these two clear_bit() 6010 */ 6011 clear_bit(NAPI_STATE_MISSED, &napi->state); 6012 clear_bit(NAPI_STATE_IN_BUSY_POLL, &napi->state); 6013 6014 local_bh_disable(); 6015 6016 if (prefer_busy_poll) { 6017 napi->defer_hard_irqs_count = READ_ONCE(napi->dev->napi_defer_hard_irqs); 6018 timeout = READ_ONCE(napi->dev->gro_flush_timeout); 6019 if (napi->defer_hard_irqs_count && timeout) { 6020 hrtimer_start(&napi->timer, ns_to_ktime(timeout), HRTIMER_MODE_REL_PINNED); 6021 skip_schedule = true; 6022 } 6023 } 6024 6025 /* All we really want here is to re-enable device interrupts. 6026 * Ideally, a new ndo_busy_poll_stop() could avoid another round. 6027 */ 6028 rc = napi->poll(napi, budget); 6029 /* We can't gro_normal_list() here, because napi->poll() might have 6030 * rearmed the napi (napi_complete_done()) in which case it could 6031 * already be running on another CPU. 6032 */ 6033 trace_napi_poll(napi, rc, budget); 6034 netpoll_poll_unlock(have_poll_lock); 6035 if (rc == budget) 6036 __busy_poll_stop(napi, skip_schedule); 6037 local_bh_enable(); 6038 } 6039 6040 void napi_busy_loop(unsigned int napi_id, 6041 bool (*loop_end)(void *, unsigned long), 6042 void *loop_end_arg, bool prefer_busy_poll, u16 budget) 6043 { 6044 unsigned long start_time = loop_end ? busy_loop_current_time() : 0; 6045 int (*napi_poll)(struct napi_struct *napi, int budget); 6046 void *have_poll_lock = NULL; 6047 struct napi_struct *napi; 6048 6049 restart: 6050 napi_poll = NULL; 6051 6052 rcu_read_lock(); 6053 6054 napi = napi_by_id(napi_id); 6055 if (!napi) 6056 goto out; 6057 6058 preempt_disable(); 6059 for (;;) { 6060 int work = 0; 6061 6062 local_bh_disable(); 6063 if (!napi_poll) { 6064 unsigned long val = READ_ONCE(napi->state); 6065 6066 /* If multiple threads are competing for this napi, 6067 * we avoid dirtying napi->state as much as we can. 6068 */ 6069 if (val & (NAPIF_STATE_DISABLE | NAPIF_STATE_SCHED | 6070 NAPIF_STATE_IN_BUSY_POLL)) { 6071 if (prefer_busy_poll) 6072 set_bit(NAPI_STATE_PREFER_BUSY_POLL, &napi->state); 6073 goto count; 6074 } 6075 if (cmpxchg(&napi->state, val, 6076 val | NAPIF_STATE_IN_BUSY_POLL | 6077 NAPIF_STATE_SCHED) != val) { 6078 if (prefer_busy_poll) 6079 set_bit(NAPI_STATE_PREFER_BUSY_POLL, &napi->state); 6080 goto count; 6081 } 6082 have_poll_lock = netpoll_poll_lock(napi); 6083 napi_poll = napi->poll; 6084 } 6085 work = napi_poll(napi, budget); 6086 trace_napi_poll(napi, work, budget); 6087 gro_normal_list(napi); 6088 count: 6089 if (work > 0) 6090 __NET_ADD_STATS(dev_net(napi->dev), 6091 LINUX_MIB_BUSYPOLLRXPACKETS, work); 6092 local_bh_enable(); 6093 6094 if (!loop_end || loop_end(loop_end_arg, start_time)) 6095 break; 6096 6097 if (unlikely(need_resched())) { 6098 if (napi_poll) 6099 busy_poll_stop(napi, have_poll_lock, prefer_busy_poll, budget); 6100 preempt_enable(); 6101 rcu_read_unlock(); 6102 cond_resched(); 6103 if (loop_end(loop_end_arg, start_time)) 6104 return; 6105 goto restart; 6106 } 6107 cpu_relax(); 6108 } 6109 if (napi_poll) 6110 busy_poll_stop(napi, have_poll_lock, prefer_busy_poll, budget); 6111 preempt_enable(); 6112 out: 6113 rcu_read_unlock(); 6114 } 6115 EXPORT_SYMBOL(napi_busy_loop); 6116 6117 #endif /* CONFIG_NET_RX_BUSY_POLL */ 6118 6119 static void napi_hash_add(struct napi_struct *napi) 6120 { 6121 if (test_bit(NAPI_STATE_NO_BUSY_POLL, &napi->state)) 6122 return; 6123 6124 spin_lock(&napi_hash_lock); 6125 6126 /* 0..NR_CPUS range is reserved for sender_cpu use */ 6127 do { 6128 if (unlikely(++napi_gen_id < MIN_NAPI_ID)) 6129 napi_gen_id = MIN_NAPI_ID; 6130 } while (napi_by_id(napi_gen_id)); 6131 napi->napi_id = napi_gen_id; 6132 6133 hlist_add_head_rcu(&napi->napi_hash_node, 6134 &napi_hash[napi->napi_id % HASH_SIZE(napi_hash)]); 6135 6136 spin_unlock(&napi_hash_lock); 6137 } 6138 6139 /* Warning : caller is responsible to make sure rcu grace period 6140 * is respected before freeing memory containing @napi 6141 */ 6142 static void napi_hash_del(struct napi_struct *napi) 6143 { 6144 spin_lock(&napi_hash_lock); 6145 6146 hlist_del_init_rcu(&napi->napi_hash_node); 6147 6148 spin_unlock(&napi_hash_lock); 6149 } 6150 6151 static enum hrtimer_restart napi_watchdog(struct hrtimer *timer) 6152 { 6153 struct napi_struct *napi; 6154 6155 napi = container_of(timer, struct napi_struct, timer); 6156 6157 /* Note : we use a relaxed variant of napi_schedule_prep() not setting 6158 * NAPI_STATE_MISSED, since we do not react to a device IRQ. 6159 */ 6160 if (!napi_disable_pending(napi) && 6161 !test_and_set_bit(NAPI_STATE_SCHED, &napi->state)) { 6162 clear_bit(NAPI_STATE_PREFER_BUSY_POLL, &napi->state); 6163 __napi_schedule_irqoff(napi); 6164 } 6165 6166 return HRTIMER_NORESTART; 6167 } 6168 6169 static void init_gro_hash(struct napi_struct *napi) 6170 { 6171 int i; 6172 6173 for (i = 0; i < GRO_HASH_BUCKETS; i++) { 6174 INIT_LIST_HEAD(&napi->gro_hash[i].list); 6175 napi->gro_hash[i].count = 0; 6176 } 6177 napi->gro_bitmask = 0; 6178 } 6179 6180 int dev_set_threaded(struct net_device *dev, bool threaded) 6181 { 6182 struct napi_struct *napi; 6183 int err = 0; 6184 6185 if (dev->threaded == threaded) 6186 return 0; 6187 6188 if (threaded) { 6189 list_for_each_entry(napi, &dev->napi_list, dev_list) { 6190 if (!napi->thread) { 6191 err = napi_kthread_create(napi); 6192 if (err) { 6193 threaded = false; 6194 break; 6195 } 6196 } 6197 } 6198 } 6199 6200 dev->threaded = threaded; 6201 6202 /* Make sure kthread is created before THREADED bit 6203 * is set. 6204 */ 6205 smp_mb__before_atomic(); 6206 6207 /* Setting/unsetting threaded mode on a napi might not immediately 6208 * take effect, if the current napi instance is actively being 6209 * polled. In this case, the switch between threaded mode and 6210 * softirq mode will happen in the next round of napi_schedule(). 6211 * This should not cause hiccups/stalls to the live traffic. 6212 */ 6213 list_for_each_entry(napi, &dev->napi_list, dev_list) { 6214 if (threaded) 6215 set_bit(NAPI_STATE_THREADED, &napi->state); 6216 else 6217 clear_bit(NAPI_STATE_THREADED, &napi->state); 6218 } 6219 6220 return err; 6221 } 6222 EXPORT_SYMBOL(dev_set_threaded); 6223 6224 void netif_napi_add(struct net_device *dev, struct napi_struct *napi, 6225 int (*poll)(struct napi_struct *, int), int weight) 6226 { 6227 if (WARN_ON(test_and_set_bit(NAPI_STATE_LISTED, &napi->state))) 6228 return; 6229 6230 INIT_LIST_HEAD(&napi->poll_list); 6231 INIT_HLIST_NODE(&napi->napi_hash_node); 6232 hrtimer_init(&napi->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_PINNED); 6233 napi->timer.function = napi_watchdog; 6234 init_gro_hash(napi); 6235 napi->skb = NULL; 6236 INIT_LIST_HEAD(&napi->rx_list); 6237 napi->rx_count = 0; 6238 napi->poll = poll; 6239 if (weight > NAPI_POLL_WEIGHT) 6240 netdev_err_once(dev, "%s() called with weight %d\n", __func__, 6241 weight); 6242 napi->weight = weight; 6243 napi->dev = dev; 6244 #ifdef CONFIG_NETPOLL 6245 napi->poll_owner = -1; 6246 #endif 6247 set_bit(NAPI_STATE_SCHED, &napi->state); 6248 set_bit(NAPI_STATE_NPSVC, &napi->state); 6249 list_add_rcu(&napi->dev_list, &dev->napi_list); 6250 napi_hash_add(napi); 6251 /* Create kthread for this napi if dev->threaded is set. 6252 * Clear dev->threaded if kthread creation failed so that 6253 * threaded mode will not be enabled in napi_enable(). 6254 */ 6255 if (dev->threaded && napi_kthread_create(napi)) 6256 dev->threaded = 0; 6257 } 6258 EXPORT_SYMBOL(netif_napi_add); 6259 6260 void napi_disable(struct napi_struct *n) 6261 { 6262 unsigned long val, new; 6263 6264 might_sleep(); 6265 set_bit(NAPI_STATE_DISABLE, &n->state); 6266 6267 for ( ; ; ) { 6268 val = READ_ONCE(n->state); 6269 if (val & (NAPIF_STATE_SCHED | NAPIF_STATE_NPSVC)) { 6270 usleep_range(20, 200); 6271 continue; 6272 } 6273 6274 new = val | NAPIF_STATE_SCHED | NAPIF_STATE_NPSVC; 6275 new &= ~(NAPIF_STATE_THREADED | NAPIF_STATE_PREFER_BUSY_POLL); 6276 6277 if (cmpxchg(&n->state, val, new) == val) 6278 break; 6279 } 6280 6281 hrtimer_cancel(&n->timer); 6282 6283 clear_bit(NAPI_STATE_DISABLE, &n->state); 6284 } 6285 EXPORT_SYMBOL(napi_disable); 6286 6287 /** 6288 * napi_enable - enable NAPI scheduling 6289 * @n: NAPI context 6290 * 6291 * Resume NAPI from being scheduled on this context. 6292 * Must be paired with napi_disable. 6293 */ 6294 void napi_enable(struct napi_struct *n) 6295 { 6296 unsigned long val, new; 6297 6298 do { 6299 val = READ_ONCE(n->state); 6300 BUG_ON(!test_bit(NAPI_STATE_SCHED, &val)); 6301 6302 new = val & ~(NAPIF_STATE_SCHED | NAPIF_STATE_NPSVC); 6303 if (n->dev->threaded && n->thread) 6304 new |= NAPIF_STATE_THREADED; 6305 } while (cmpxchg(&n->state, val, new) != val); 6306 } 6307 EXPORT_SYMBOL(napi_enable); 6308 6309 static void flush_gro_hash(struct napi_struct *napi) 6310 { 6311 int i; 6312 6313 for (i = 0; i < GRO_HASH_BUCKETS; i++) { 6314 struct sk_buff *skb, *n; 6315 6316 list_for_each_entry_safe(skb, n, &napi->gro_hash[i].list, list) 6317 kfree_skb(skb); 6318 napi->gro_hash[i].count = 0; 6319 } 6320 } 6321 6322 /* Must be called in process context */ 6323 void __netif_napi_del(struct napi_struct *napi) 6324 { 6325 if (!test_and_clear_bit(NAPI_STATE_LISTED, &napi->state)) 6326 return; 6327 6328 napi_hash_del(napi); 6329 list_del_rcu(&napi->dev_list); 6330 napi_free_frags(napi); 6331 6332 flush_gro_hash(napi); 6333 napi->gro_bitmask = 0; 6334 6335 if (napi->thread) { 6336 kthread_stop(napi->thread); 6337 napi->thread = NULL; 6338 } 6339 } 6340 EXPORT_SYMBOL(__netif_napi_del); 6341 6342 static int __napi_poll(struct napi_struct *n, bool *repoll) 6343 { 6344 int work, weight; 6345 6346 weight = n->weight; 6347 6348 /* This NAPI_STATE_SCHED test is for avoiding a race 6349 * with netpoll's poll_napi(). Only the entity which 6350 * obtains the lock and sees NAPI_STATE_SCHED set will 6351 * actually make the ->poll() call. Therefore we avoid 6352 * accidentally calling ->poll() when NAPI is not scheduled. 6353 */ 6354 work = 0; 6355 if (test_bit(NAPI_STATE_SCHED, &n->state)) { 6356 work = n->poll(n, weight); 6357 trace_napi_poll(n, work, weight); 6358 } 6359 6360 if (unlikely(work > weight)) 6361 netdev_err_once(n->dev, "NAPI poll function %pS returned %d, exceeding its budget of %d.\n", 6362 n->poll, work, weight); 6363 6364 if (likely(work < weight)) 6365 return work; 6366 6367 /* Drivers must not modify the NAPI state if they 6368 * consume the entire weight. In such cases this code 6369 * still "owns" the NAPI instance and therefore can 6370 * move the instance around on the list at-will. 6371 */ 6372 if (unlikely(napi_disable_pending(n))) { 6373 napi_complete(n); 6374 return work; 6375 } 6376 6377 /* The NAPI context has more processing work, but busy-polling 6378 * is preferred. Exit early. 6379 */ 6380 if (napi_prefer_busy_poll(n)) { 6381 if (napi_complete_done(n, work)) { 6382 /* If timeout is not set, we need to make sure 6383 * that the NAPI is re-scheduled. 6384 */ 6385 napi_schedule(n); 6386 } 6387 return work; 6388 } 6389 6390 if (n->gro_bitmask) { 6391 /* flush too old packets 6392 * If HZ < 1000, flush all packets. 6393 */ 6394 napi_gro_flush(n, HZ >= 1000); 6395 } 6396 6397 gro_normal_list(n); 6398 6399 /* Some drivers may have called napi_schedule 6400 * prior to exhausting their budget. 6401 */ 6402 if (unlikely(!list_empty(&n->poll_list))) { 6403 pr_warn_once("%s: Budget exhausted after napi rescheduled\n", 6404 n->dev ? n->dev->name : "backlog"); 6405 return work; 6406 } 6407 6408 *repoll = true; 6409 6410 return work; 6411 } 6412 6413 static int napi_poll(struct napi_struct *n, struct list_head *repoll) 6414 { 6415 bool do_repoll = false; 6416 void *have; 6417 int work; 6418 6419 list_del_init(&n->poll_list); 6420 6421 have = netpoll_poll_lock(n); 6422 6423 work = __napi_poll(n, &do_repoll); 6424 6425 if (do_repoll) 6426 list_add_tail(&n->poll_list, repoll); 6427 6428 netpoll_poll_unlock(have); 6429 6430 return work; 6431 } 6432 6433 static int napi_thread_wait(struct napi_struct *napi) 6434 { 6435 bool woken = false; 6436 6437 set_current_state(TASK_INTERRUPTIBLE); 6438 6439 while (!kthread_should_stop()) { 6440 /* Testing SCHED_THREADED bit here to make sure the current 6441 * kthread owns this napi and could poll on this napi. 6442 * Testing SCHED bit is not enough because SCHED bit might be 6443 * set by some other busy poll thread or by napi_disable(). 6444 */ 6445 if (test_bit(NAPI_STATE_SCHED_THREADED, &napi->state) || woken) { 6446 WARN_ON(!list_empty(&napi->poll_list)); 6447 __set_current_state(TASK_RUNNING); 6448 return 0; 6449 } 6450 6451 schedule(); 6452 /* woken being true indicates this thread owns this napi. */ 6453 woken = true; 6454 set_current_state(TASK_INTERRUPTIBLE); 6455 } 6456 __set_current_state(TASK_RUNNING); 6457 6458 return -1; 6459 } 6460 6461 static int napi_threaded_poll(void *data) 6462 { 6463 struct napi_struct *napi = data; 6464 void *have; 6465 6466 while (!napi_thread_wait(napi)) { 6467 for (;;) { 6468 bool repoll = false; 6469 6470 local_bh_disable(); 6471 6472 have = netpoll_poll_lock(napi); 6473 __napi_poll(napi, &repoll); 6474 netpoll_poll_unlock(have); 6475 6476 local_bh_enable(); 6477 6478 if (!repoll) 6479 break; 6480 6481 cond_resched(); 6482 } 6483 } 6484 return 0; 6485 } 6486 6487 static __latent_entropy void net_rx_action(struct softirq_action *h) 6488 { 6489 struct softnet_data *sd = this_cpu_ptr(&softnet_data); 6490 unsigned long time_limit = jiffies + 6491 usecs_to_jiffies(netdev_budget_usecs); 6492 int budget = netdev_budget; 6493 LIST_HEAD(list); 6494 LIST_HEAD(repoll); 6495 6496 local_irq_disable(); 6497 list_splice_init(&sd->poll_list, &list); 6498 local_irq_enable(); 6499 6500 for (;;) { 6501 struct napi_struct *n; 6502 6503 if (list_empty(&list)) { 6504 if (!sd_has_rps_ipi_waiting(sd) && list_empty(&repoll)) 6505 return; 6506 break; 6507 } 6508 6509 n = list_first_entry(&list, struct napi_struct, poll_list); 6510 budget -= napi_poll(n, &repoll); 6511 6512 /* If softirq window is exhausted then punt. 6513 * Allow this to run for 2 jiffies since which will allow 6514 * an average latency of 1.5/HZ. 6515 */ 6516 if (unlikely(budget <= 0 || 6517 time_after_eq(jiffies, time_limit))) { 6518 sd->time_squeeze++; 6519 break; 6520 } 6521 } 6522 6523 local_irq_disable(); 6524 6525 list_splice_tail_init(&sd->poll_list, &list); 6526 list_splice_tail(&repoll, &list); 6527 list_splice(&list, &sd->poll_list); 6528 if (!list_empty(&sd->poll_list)) 6529 __raise_softirq_irqoff(NET_RX_SOFTIRQ); 6530 6531 net_rps_action_and_irq_enable(sd); 6532 } 6533 6534 struct netdev_adjacent { 6535 struct net_device *dev; 6536 6537 /* upper master flag, there can only be one master device per list */ 6538 bool master; 6539 6540 /* lookup ignore flag */ 6541 bool ignore; 6542 6543 /* counter for the number of times this device was added to us */ 6544 u16 ref_nr; 6545 6546 /* private field for the users */ 6547 void *private; 6548 6549 struct list_head list; 6550 struct rcu_head rcu; 6551 }; 6552 6553 static struct netdev_adjacent *__netdev_find_adj(struct net_device *adj_dev, 6554 struct list_head *adj_list) 6555 { 6556 struct netdev_adjacent *adj; 6557 6558 list_for_each_entry(adj, adj_list, list) { 6559 if (adj->dev == adj_dev) 6560 return adj; 6561 } 6562 return NULL; 6563 } 6564 6565 static int ____netdev_has_upper_dev(struct net_device *upper_dev, 6566 struct netdev_nested_priv *priv) 6567 { 6568 struct net_device *dev = (struct net_device *)priv->data; 6569 6570 return upper_dev == dev; 6571 } 6572 6573 /** 6574 * netdev_has_upper_dev - Check if device is linked to an upper device 6575 * @dev: device 6576 * @upper_dev: upper device to check 6577 * 6578 * Find out if a device is linked to specified upper device and return true 6579 * in case it is. Note that this checks only immediate upper device, 6580 * not through a complete stack of devices. The caller must hold the RTNL lock. 6581 */ 6582 bool netdev_has_upper_dev(struct net_device *dev, 6583 struct net_device *upper_dev) 6584 { 6585 struct netdev_nested_priv priv = { 6586 .data = (void *)upper_dev, 6587 }; 6588 6589 ASSERT_RTNL(); 6590 6591 return netdev_walk_all_upper_dev_rcu(dev, ____netdev_has_upper_dev, 6592 &priv); 6593 } 6594 EXPORT_SYMBOL(netdev_has_upper_dev); 6595 6596 /** 6597 * netdev_has_upper_dev_all_rcu - Check if device is linked to an upper device 6598 * @dev: device 6599 * @upper_dev: upper device to check 6600 * 6601 * Find out if a device is linked to specified upper device and return true 6602 * in case it is. Note that this checks the entire upper device chain. 6603 * The caller must hold rcu lock. 6604 */ 6605 6606 bool netdev_has_upper_dev_all_rcu(struct net_device *dev, 6607 struct net_device *upper_dev) 6608 { 6609 struct netdev_nested_priv priv = { 6610 .data = (void *)upper_dev, 6611 }; 6612 6613 return !!netdev_walk_all_upper_dev_rcu(dev, ____netdev_has_upper_dev, 6614 &priv); 6615 } 6616 EXPORT_SYMBOL(netdev_has_upper_dev_all_rcu); 6617 6618 /** 6619 * netdev_has_any_upper_dev - Check if device is linked to some device 6620 * @dev: device 6621 * 6622 * Find out if a device is linked to an upper device and return true in case 6623 * it is. The caller must hold the RTNL lock. 6624 */ 6625 bool netdev_has_any_upper_dev(struct net_device *dev) 6626 { 6627 ASSERT_RTNL(); 6628 6629 return !list_empty(&dev->adj_list.upper); 6630 } 6631 EXPORT_SYMBOL(netdev_has_any_upper_dev); 6632 6633 /** 6634 * netdev_master_upper_dev_get - Get master upper device 6635 * @dev: device 6636 * 6637 * Find a master upper device and return pointer to it or NULL in case 6638 * it's not there. The caller must hold the RTNL lock. 6639 */ 6640 struct net_device *netdev_master_upper_dev_get(struct net_device *dev) 6641 { 6642 struct netdev_adjacent *upper; 6643 6644 ASSERT_RTNL(); 6645 6646 if (list_empty(&dev->adj_list.upper)) 6647 return NULL; 6648 6649 upper = list_first_entry(&dev->adj_list.upper, 6650 struct netdev_adjacent, list); 6651 if (likely(upper->master)) 6652 return upper->dev; 6653 return NULL; 6654 } 6655 EXPORT_SYMBOL(netdev_master_upper_dev_get); 6656 6657 static struct net_device *__netdev_master_upper_dev_get(struct net_device *dev) 6658 { 6659 struct netdev_adjacent *upper; 6660 6661 ASSERT_RTNL(); 6662 6663 if (list_empty(&dev->adj_list.upper)) 6664 return NULL; 6665 6666 upper = list_first_entry(&dev->adj_list.upper, 6667 struct netdev_adjacent, list); 6668 if (likely(upper->master) && !upper->ignore) 6669 return upper->dev; 6670 return NULL; 6671 } 6672 6673 /** 6674 * netdev_has_any_lower_dev - Check if device is linked to some device 6675 * @dev: device 6676 * 6677 * Find out if a device is linked to a lower device and return true in case 6678 * it is. The caller must hold the RTNL lock. 6679 */ 6680 static bool netdev_has_any_lower_dev(struct net_device *dev) 6681 { 6682 ASSERT_RTNL(); 6683 6684 return !list_empty(&dev->adj_list.lower); 6685 } 6686 6687 void *netdev_adjacent_get_private(struct list_head *adj_list) 6688 { 6689 struct netdev_adjacent *adj; 6690 6691 adj = list_entry(adj_list, struct netdev_adjacent, list); 6692 6693 return adj->private; 6694 } 6695 EXPORT_SYMBOL(netdev_adjacent_get_private); 6696 6697 /** 6698 * netdev_upper_get_next_dev_rcu - Get the next dev from upper list 6699 * @dev: device 6700 * @iter: list_head ** of the current position 6701 * 6702 * Gets the next device from the dev's upper list, starting from iter 6703 * position. The caller must hold RCU read lock. 6704 */ 6705 struct net_device *netdev_upper_get_next_dev_rcu(struct net_device *dev, 6706 struct list_head **iter) 6707 { 6708 struct netdev_adjacent *upper; 6709 6710 WARN_ON_ONCE(!rcu_read_lock_held() && !lockdep_rtnl_is_held()); 6711 6712 upper = list_entry_rcu((*iter)->next, struct netdev_adjacent, list); 6713 6714 if (&upper->list == &dev->adj_list.upper) 6715 return NULL; 6716 6717 *iter = &upper->list; 6718 6719 return upper->dev; 6720 } 6721 EXPORT_SYMBOL(netdev_upper_get_next_dev_rcu); 6722 6723 static struct net_device *__netdev_next_upper_dev(struct net_device *dev, 6724 struct list_head **iter, 6725 bool *ignore) 6726 { 6727 struct netdev_adjacent *upper; 6728 6729 upper = list_entry((*iter)->next, struct netdev_adjacent, list); 6730 6731 if (&upper->list == &dev->adj_list.upper) 6732 return NULL; 6733 6734 *iter = &upper->list; 6735 *ignore = upper->ignore; 6736 6737 return upper->dev; 6738 } 6739 6740 static struct net_device *netdev_next_upper_dev_rcu(struct net_device *dev, 6741 struct list_head **iter) 6742 { 6743 struct netdev_adjacent *upper; 6744 6745 WARN_ON_ONCE(!rcu_read_lock_held() && !lockdep_rtnl_is_held()); 6746 6747 upper = list_entry_rcu((*iter)->next, struct netdev_adjacent, list); 6748 6749 if (&upper->list == &dev->adj_list.upper) 6750 return NULL; 6751 6752 *iter = &upper->list; 6753 6754 return upper->dev; 6755 } 6756 6757 static int __netdev_walk_all_upper_dev(struct net_device *dev, 6758 int (*fn)(struct net_device *dev, 6759 struct netdev_nested_priv *priv), 6760 struct netdev_nested_priv *priv) 6761 { 6762 struct net_device *udev, *next, *now, *dev_stack[MAX_NEST_DEV + 1]; 6763 struct list_head *niter, *iter, *iter_stack[MAX_NEST_DEV + 1]; 6764 int ret, cur = 0; 6765 bool ignore; 6766 6767 now = dev; 6768 iter = &dev->adj_list.upper; 6769 6770 while (1) { 6771 if (now != dev) { 6772 ret = fn(now, priv); 6773 if (ret) 6774 return ret; 6775 } 6776 6777 next = NULL; 6778 while (1) { 6779 udev = __netdev_next_upper_dev(now, &iter, &ignore); 6780 if (!udev) 6781 break; 6782 if (ignore) 6783 continue; 6784 6785 next = udev; 6786 niter = &udev->adj_list.upper; 6787 dev_stack[cur] = now; 6788 iter_stack[cur++] = iter; 6789 break; 6790 } 6791 6792 if (!next) { 6793 if (!cur) 6794 return 0; 6795 next = dev_stack[--cur]; 6796 niter = iter_stack[cur]; 6797 } 6798 6799 now = next; 6800 iter = niter; 6801 } 6802 6803 return 0; 6804 } 6805 6806 int netdev_walk_all_upper_dev_rcu(struct net_device *dev, 6807 int (*fn)(struct net_device *dev, 6808 struct netdev_nested_priv *priv), 6809 struct netdev_nested_priv *priv) 6810 { 6811 struct net_device *udev, *next, *now, *dev_stack[MAX_NEST_DEV + 1]; 6812 struct list_head *niter, *iter, *iter_stack[MAX_NEST_DEV + 1]; 6813 int ret, cur = 0; 6814 6815 now = dev; 6816 iter = &dev->adj_list.upper; 6817 6818 while (1) { 6819 if (now != dev) { 6820 ret = fn(now, priv); 6821 if (ret) 6822 return ret; 6823 } 6824 6825 next = NULL; 6826 while (1) { 6827 udev = netdev_next_upper_dev_rcu(now, &iter); 6828 if (!udev) 6829 break; 6830 6831 next = udev; 6832 niter = &udev->adj_list.upper; 6833 dev_stack[cur] = now; 6834 iter_stack[cur++] = iter; 6835 break; 6836 } 6837 6838 if (!next) { 6839 if (!cur) 6840 return 0; 6841 next = dev_stack[--cur]; 6842 niter = iter_stack[cur]; 6843 } 6844 6845 now = next; 6846 iter = niter; 6847 } 6848 6849 return 0; 6850 } 6851 EXPORT_SYMBOL_GPL(netdev_walk_all_upper_dev_rcu); 6852 6853 static bool __netdev_has_upper_dev(struct net_device *dev, 6854 struct net_device *upper_dev) 6855 { 6856 struct netdev_nested_priv priv = { 6857 .flags = 0, 6858 .data = (void *)upper_dev, 6859 }; 6860 6861 ASSERT_RTNL(); 6862 6863 return __netdev_walk_all_upper_dev(dev, ____netdev_has_upper_dev, 6864 &priv); 6865 } 6866 6867 /** 6868 * netdev_lower_get_next_private - Get the next ->private from the 6869 * lower neighbour list 6870 * @dev: device 6871 * @iter: list_head ** of the current position 6872 * 6873 * Gets the next netdev_adjacent->private from the dev's lower neighbour 6874 * list, starting from iter position. The caller must hold either hold the 6875 * RTNL lock or its own locking that guarantees that the neighbour lower 6876 * list will remain unchanged. 6877 */ 6878 void *netdev_lower_get_next_private(struct net_device *dev, 6879 struct list_head **iter) 6880 { 6881 struct netdev_adjacent *lower; 6882 6883 lower = list_entry(*iter, struct netdev_adjacent, list); 6884 6885 if (&lower->list == &dev->adj_list.lower) 6886 return NULL; 6887 6888 *iter = lower->list.next; 6889 6890 return lower->private; 6891 } 6892 EXPORT_SYMBOL(netdev_lower_get_next_private); 6893 6894 /** 6895 * netdev_lower_get_next_private_rcu - Get the next ->private from the 6896 * lower neighbour list, RCU 6897 * variant 6898 * @dev: device 6899 * @iter: list_head ** of the current position 6900 * 6901 * Gets the next netdev_adjacent->private from the dev's lower neighbour 6902 * list, starting from iter position. The caller must hold RCU read lock. 6903 */ 6904 void *netdev_lower_get_next_private_rcu(struct net_device *dev, 6905 struct list_head **iter) 6906 { 6907 struct netdev_adjacent *lower; 6908 6909 WARN_ON_ONCE(!rcu_read_lock_held() && !rcu_read_lock_bh_held()); 6910 6911 lower = list_entry_rcu((*iter)->next, struct netdev_adjacent, list); 6912 6913 if (&lower->list == &dev->adj_list.lower) 6914 return NULL; 6915 6916 *iter = &lower->list; 6917 6918 return lower->private; 6919 } 6920 EXPORT_SYMBOL(netdev_lower_get_next_private_rcu); 6921 6922 /** 6923 * netdev_lower_get_next - Get the next device from the lower neighbour 6924 * list 6925 * @dev: device 6926 * @iter: list_head ** of the current position 6927 * 6928 * Gets the next netdev_adjacent from the dev's lower neighbour 6929 * list, starting from iter position. The caller must hold RTNL lock or 6930 * its own locking that guarantees that the neighbour lower 6931 * list will remain unchanged. 6932 */ 6933 void *netdev_lower_get_next(struct net_device *dev, struct list_head **iter) 6934 { 6935 struct netdev_adjacent *lower; 6936 6937 lower = list_entry(*iter, struct netdev_adjacent, list); 6938 6939 if (&lower->list == &dev->adj_list.lower) 6940 return NULL; 6941 6942 *iter = lower->list.next; 6943 6944 return lower->dev; 6945 } 6946 EXPORT_SYMBOL(netdev_lower_get_next); 6947 6948 static struct net_device *netdev_next_lower_dev(struct net_device *dev, 6949 struct list_head **iter) 6950 { 6951 struct netdev_adjacent *lower; 6952 6953 lower = list_entry((*iter)->next, struct netdev_adjacent, list); 6954 6955 if (&lower->list == &dev->adj_list.lower) 6956 return NULL; 6957 6958 *iter = &lower->list; 6959 6960 return lower->dev; 6961 } 6962 6963 static struct net_device *__netdev_next_lower_dev(struct net_device *dev, 6964 struct list_head **iter, 6965 bool *ignore) 6966 { 6967 struct netdev_adjacent *lower; 6968 6969 lower = list_entry((*iter)->next, struct netdev_adjacent, list); 6970 6971 if (&lower->list == &dev->adj_list.lower) 6972 return NULL; 6973 6974 *iter = &lower->list; 6975 *ignore = lower->ignore; 6976 6977 return lower->dev; 6978 } 6979 6980 int netdev_walk_all_lower_dev(struct net_device *dev, 6981 int (*fn)(struct net_device *dev, 6982 struct netdev_nested_priv *priv), 6983 struct netdev_nested_priv *priv) 6984 { 6985 struct net_device *ldev, *next, *now, *dev_stack[MAX_NEST_DEV + 1]; 6986 struct list_head *niter, *iter, *iter_stack[MAX_NEST_DEV + 1]; 6987 int ret, cur = 0; 6988 6989 now = dev; 6990 iter = &dev->adj_list.lower; 6991 6992 while (1) { 6993 if (now != dev) { 6994 ret = fn(now, priv); 6995 if (ret) 6996 return ret; 6997 } 6998 6999 next = NULL; 7000 while (1) { 7001 ldev = netdev_next_lower_dev(now, &iter); 7002 if (!ldev) 7003 break; 7004 7005 next = ldev; 7006 niter = &ldev->adj_list.lower; 7007 dev_stack[cur] = now; 7008 iter_stack[cur++] = iter; 7009 break; 7010 } 7011 7012 if (!next) { 7013 if (!cur) 7014 return 0; 7015 next = dev_stack[--cur]; 7016 niter = iter_stack[cur]; 7017 } 7018 7019 now = next; 7020 iter = niter; 7021 } 7022 7023 return 0; 7024 } 7025 EXPORT_SYMBOL_GPL(netdev_walk_all_lower_dev); 7026 7027 static int __netdev_walk_all_lower_dev(struct net_device *dev, 7028 int (*fn)(struct net_device *dev, 7029 struct netdev_nested_priv *priv), 7030 struct netdev_nested_priv *priv) 7031 { 7032 struct net_device *ldev, *next, *now, *dev_stack[MAX_NEST_DEV + 1]; 7033 struct list_head *niter, *iter, *iter_stack[MAX_NEST_DEV + 1]; 7034 int ret, cur = 0; 7035 bool ignore; 7036 7037 now = dev; 7038 iter = &dev->adj_list.lower; 7039 7040 while (1) { 7041 if (now != dev) { 7042 ret = fn(now, priv); 7043 if (ret) 7044 return ret; 7045 } 7046 7047 next = NULL; 7048 while (1) { 7049 ldev = __netdev_next_lower_dev(now, &iter, &ignore); 7050 if (!ldev) 7051 break; 7052 if (ignore) 7053 continue; 7054 7055 next = ldev; 7056 niter = &ldev->adj_list.lower; 7057 dev_stack[cur] = now; 7058 iter_stack[cur++] = iter; 7059 break; 7060 } 7061 7062 if (!next) { 7063 if (!cur) 7064 return 0; 7065 next = dev_stack[--cur]; 7066 niter = iter_stack[cur]; 7067 } 7068 7069 now = next; 7070 iter = niter; 7071 } 7072 7073 return 0; 7074 } 7075 7076 struct net_device *netdev_next_lower_dev_rcu(struct net_device *dev, 7077 struct list_head **iter) 7078 { 7079 struct netdev_adjacent *lower; 7080 7081 lower = list_entry_rcu((*iter)->next, struct netdev_adjacent, list); 7082 if (&lower->list == &dev->adj_list.lower) 7083 return NULL; 7084 7085 *iter = &lower->list; 7086 7087 return lower->dev; 7088 } 7089 EXPORT_SYMBOL(netdev_next_lower_dev_rcu); 7090 7091 static u8 __netdev_upper_depth(struct net_device *dev) 7092 { 7093 struct net_device *udev; 7094 struct list_head *iter; 7095 u8 max_depth = 0; 7096 bool ignore; 7097 7098 for (iter = &dev->adj_list.upper, 7099 udev = __netdev_next_upper_dev(dev, &iter, &ignore); 7100 udev; 7101 udev = __netdev_next_upper_dev(dev, &iter, &ignore)) { 7102 if (ignore) 7103 continue; 7104 if (max_depth < udev->upper_level) 7105 max_depth = udev->upper_level; 7106 } 7107 7108 return max_depth; 7109 } 7110 7111 static u8 __netdev_lower_depth(struct net_device *dev) 7112 { 7113 struct net_device *ldev; 7114 struct list_head *iter; 7115 u8 max_depth = 0; 7116 bool ignore; 7117 7118 for (iter = &dev->adj_list.lower, 7119 ldev = __netdev_next_lower_dev(dev, &iter, &ignore); 7120 ldev; 7121 ldev = __netdev_next_lower_dev(dev, &iter, &ignore)) { 7122 if (ignore) 7123 continue; 7124 if (max_depth < ldev->lower_level) 7125 max_depth = ldev->lower_level; 7126 } 7127 7128 return max_depth; 7129 } 7130 7131 static int __netdev_update_upper_level(struct net_device *dev, 7132 struct netdev_nested_priv *__unused) 7133 { 7134 dev->upper_level = __netdev_upper_depth(dev) + 1; 7135 return 0; 7136 } 7137 7138 static int __netdev_update_lower_level(struct net_device *dev, 7139 struct netdev_nested_priv *priv) 7140 { 7141 dev->lower_level = __netdev_lower_depth(dev) + 1; 7142 7143 #ifdef CONFIG_LOCKDEP 7144 if (!priv) 7145 return 0; 7146 7147 if (priv->flags & NESTED_SYNC_IMM) 7148 dev->nested_level = dev->lower_level - 1; 7149 if (priv->flags & NESTED_SYNC_TODO) 7150 net_unlink_todo(dev); 7151 #endif 7152 return 0; 7153 } 7154 7155 int netdev_walk_all_lower_dev_rcu(struct net_device *dev, 7156 int (*fn)(struct net_device *dev, 7157 struct netdev_nested_priv *priv), 7158 struct netdev_nested_priv *priv) 7159 { 7160 struct net_device *ldev, *next, *now, *dev_stack[MAX_NEST_DEV + 1]; 7161 struct list_head *niter, *iter, *iter_stack[MAX_NEST_DEV + 1]; 7162 int ret, cur = 0; 7163 7164 now = dev; 7165 iter = &dev->adj_list.lower; 7166 7167 while (1) { 7168 if (now != dev) { 7169 ret = fn(now, priv); 7170 if (ret) 7171 return ret; 7172 } 7173 7174 next = NULL; 7175 while (1) { 7176 ldev = netdev_next_lower_dev_rcu(now, &iter); 7177 if (!ldev) 7178 break; 7179 7180 next = ldev; 7181 niter = &ldev->adj_list.lower; 7182 dev_stack[cur] = now; 7183 iter_stack[cur++] = iter; 7184 break; 7185 } 7186 7187 if (!next) { 7188 if (!cur) 7189 return 0; 7190 next = dev_stack[--cur]; 7191 niter = iter_stack[cur]; 7192 } 7193 7194 now = next; 7195 iter = niter; 7196 } 7197 7198 return 0; 7199 } 7200 EXPORT_SYMBOL_GPL(netdev_walk_all_lower_dev_rcu); 7201 7202 /** 7203 * netdev_lower_get_first_private_rcu - Get the first ->private from the 7204 * lower neighbour list, RCU 7205 * variant 7206 * @dev: device 7207 * 7208 * Gets the first netdev_adjacent->private from the dev's lower neighbour 7209 * list. The caller must hold RCU read lock. 7210 */ 7211 void *netdev_lower_get_first_private_rcu(struct net_device *dev) 7212 { 7213 struct netdev_adjacent *lower; 7214 7215 lower = list_first_or_null_rcu(&dev->adj_list.lower, 7216 struct netdev_adjacent, list); 7217 if (lower) 7218 return lower->private; 7219 return NULL; 7220 } 7221 EXPORT_SYMBOL(netdev_lower_get_first_private_rcu); 7222 7223 /** 7224 * netdev_master_upper_dev_get_rcu - Get master upper device 7225 * @dev: device 7226 * 7227 * Find a master upper device and return pointer to it or NULL in case 7228 * it's not there. The caller must hold the RCU read lock. 7229 */ 7230 struct net_device *netdev_master_upper_dev_get_rcu(struct net_device *dev) 7231 { 7232 struct netdev_adjacent *upper; 7233 7234 upper = list_first_or_null_rcu(&dev->adj_list.upper, 7235 struct netdev_adjacent, list); 7236 if (upper && likely(upper->master)) 7237 return upper->dev; 7238 return NULL; 7239 } 7240 EXPORT_SYMBOL(netdev_master_upper_dev_get_rcu); 7241 7242 static int netdev_adjacent_sysfs_add(struct net_device *dev, 7243 struct net_device *adj_dev, 7244 struct list_head *dev_list) 7245 { 7246 char linkname[IFNAMSIZ+7]; 7247 7248 sprintf(linkname, dev_list == &dev->adj_list.upper ? 7249 "upper_%s" : "lower_%s", adj_dev->name); 7250 return sysfs_create_link(&(dev->dev.kobj), &(adj_dev->dev.kobj), 7251 linkname); 7252 } 7253 static void netdev_adjacent_sysfs_del(struct net_device *dev, 7254 char *name, 7255 struct list_head *dev_list) 7256 { 7257 char linkname[IFNAMSIZ+7]; 7258 7259 sprintf(linkname, dev_list == &dev->adj_list.upper ? 7260 "upper_%s" : "lower_%s", name); 7261 sysfs_remove_link(&(dev->dev.kobj), linkname); 7262 } 7263 7264 static inline bool netdev_adjacent_is_neigh_list(struct net_device *dev, 7265 struct net_device *adj_dev, 7266 struct list_head *dev_list) 7267 { 7268 return (dev_list == &dev->adj_list.upper || 7269 dev_list == &dev->adj_list.lower) && 7270 net_eq(dev_net(dev), dev_net(adj_dev)); 7271 } 7272 7273 static int __netdev_adjacent_dev_insert(struct net_device *dev, 7274 struct net_device *adj_dev, 7275 struct list_head *dev_list, 7276 void *private, bool master) 7277 { 7278 struct netdev_adjacent *adj; 7279 int ret; 7280 7281 adj = __netdev_find_adj(adj_dev, dev_list); 7282 7283 if (adj) { 7284 adj->ref_nr += 1; 7285 pr_debug("Insert adjacency: dev %s adj_dev %s adj->ref_nr %d\n", 7286 dev->name, adj_dev->name, adj->ref_nr); 7287 7288 return 0; 7289 } 7290 7291 adj = kmalloc(sizeof(*adj), GFP_KERNEL); 7292 if (!adj) 7293 return -ENOMEM; 7294 7295 adj->dev = adj_dev; 7296 adj->master = master; 7297 adj->ref_nr = 1; 7298 adj->private = private; 7299 adj->ignore = false; 7300 dev_hold(adj_dev); 7301 7302 pr_debug("Insert adjacency: dev %s adj_dev %s adj->ref_nr %d; dev_hold on %s\n", 7303 dev->name, adj_dev->name, adj->ref_nr, adj_dev->name); 7304 7305 if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list)) { 7306 ret = netdev_adjacent_sysfs_add(dev, adj_dev, dev_list); 7307 if (ret) 7308 goto free_adj; 7309 } 7310 7311 /* Ensure that master link is always the first item in list. */ 7312 if (master) { 7313 ret = sysfs_create_link(&(dev->dev.kobj), 7314 &(adj_dev->dev.kobj), "master"); 7315 if (ret) 7316 goto remove_symlinks; 7317 7318 list_add_rcu(&adj->list, dev_list); 7319 } else { 7320 list_add_tail_rcu(&adj->list, dev_list); 7321 } 7322 7323 return 0; 7324 7325 remove_symlinks: 7326 if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list)) 7327 netdev_adjacent_sysfs_del(dev, adj_dev->name, dev_list); 7328 free_adj: 7329 kfree(adj); 7330 dev_put(adj_dev); 7331 7332 return ret; 7333 } 7334 7335 static void __netdev_adjacent_dev_remove(struct net_device *dev, 7336 struct net_device *adj_dev, 7337 u16 ref_nr, 7338 struct list_head *dev_list) 7339 { 7340 struct netdev_adjacent *adj; 7341 7342 pr_debug("Remove adjacency: dev %s adj_dev %s ref_nr %d\n", 7343 dev->name, adj_dev->name, ref_nr); 7344 7345 adj = __netdev_find_adj(adj_dev, dev_list); 7346 7347 if (!adj) { 7348 pr_err("Adjacency does not exist for device %s from %s\n", 7349 dev->name, adj_dev->name); 7350 WARN_ON(1); 7351 return; 7352 } 7353 7354 if (adj->ref_nr > ref_nr) { 7355 pr_debug("adjacency: %s to %s ref_nr - %d = %d\n", 7356 dev->name, adj_dev->name, ref_nr, 7357 adj->ref_nr - ref_nr); 7358 adj->ref_nr -= ref_nr; 7359 return; 7360 } 7361 7362 if (adj->master) 7363 sysfs_remove_link(&(dev->dev.kobj), "master"); 7364 7365 if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list)) 7366 netdev_adjacent_sysfs_del(dev, adj_dev->name, dev_list); 7367 7368 list_del_rcu(&adj->list); 7369 pr_debug("adjacency: dev_put for %s, because link removed from %s to %s\n", 7370 adj_dev->name, dev->name, adj_dev->name); 7371 dev_put(adj_dev); 7372 kfree_rcu(adj, rcu); 7373 } 7374 7375 static int __netdev_adjacent_dev_link_lists(struct net_device *dev, 7376 struct net_device *upper_dev, 7377 struct list_head *up_list, 7378 struct list_head *down_list, 7379 void *private, bool master) 7380 { 7381 int ret; 7382 7383 ret = __netdev_adjacent_dev_insert(dev, upper_dev, up_list, 7384 private, master); 7385 if (ret) 7386 return ret; 7387 7388 ret = __netdev_adjacent_dev_insert(upper_dev, dev, down_list, 7389 private, false); 7390 if (ret) { 7391 __netdev_adjacent_dev_remove(dev, upper_dev, 1, up_list); 7392 return ret; 7393 } 7394 7395 return 0; 7396 } 7397 7398 static void __netdev_adjacent_dev_unlink_lists(struct net_device *dev, 7399 struct net_device *upper_dev, 7400 u16 ref_nr, 7401 struct list_head *up_list, 7402 struct list_head *down_list) 7403 { 7404 __netdev_adjacent_dev_remove(dev, upper_dev, ref_nr, up_list); 7405 __netdev_adjacent_dev_remove(upper_dev, dev, ref_nr, down_list); 7406 } 7407 7408 static int __netdev_adjacent_dev_link_neighbour(struct net_device *dev, 7409 struct net_device *upper_dev, 7410 void *private, bool master) 7411 { 7412 return __netdev_adjacent_dev_link_lists(dev, upper_dev, 7413 &dev->adj_list.upper, 7414 &upper_dev->adj_list.lower, 7415 private, master); 7416 } 7417 7418 static void __netdev_adjacent_dev_unlink_neighbour(struct net_device *dev, 7419 struct net_device *upper_dev) 7420 { 7421 __netdev_adjacent_dev_unlink_lists(dev, upper_dev, 1, 7422 &dev->adj_list.upper, 7423 &upper_dev->adj_list.lower); 7424 } 7425 7426 static int __netdev_upper_dev_link(struct net_device *dev, 7427 struct net_device *upper_dev, bool master, 7428 void *upper_priv, void *upper_info, 7429 struct netdev_nested_priv *priv, 7430 struct netlink_ext_ack *extack) 7431 { 7432 struct netdev_notifier_changeupper_info changeupper_info = { 7433 .info = { 7434 .dev = dev, 7435 .extack = extack, 7436 }, 7437 .upper_dev = upper_dev, 7438 .master = master, 7439 .linking = true, 7440 .upper_info = upper_info, 7441 }; 7442 struct net_device *master_dev; 7443 int ret = 0; 7444 7445 ASSERT_RTNL(); 7446 7447 if (dev == upper_dev) 7448 return -EBUSY; 7449 7450 /* To prevent loops, check if dev is not upper device to upper_dev. */ 7451 if (__netdev_has_upper_dev(upper_dev, dev)) 7452 return -EBUSY; 7453 7454 if ((dev->lower_level + upper_dev->upper_level) > MAX_NEST_DEV) 7455 return -EMLINK; 7456 7457 if (!master) { 7458 if (__netdev_has_upper_dev(dev, upper_dev)) 7459 return -EEXIST; 7460 } else { 7461 master_dev = __netdev_master_upper_dev_get(dev); 7462 if (master_dev) 7463 return master_dev == upper_dev ? -EEXIST : -EBUSY; 7464 } 7465 7466 ret = call_netdevice_notifiers_info(NETDEV_PRECHANGEUPPER, 7467 &changeupper_info.info); 7468 ret = notifier_to_errno(ret); 7469 if (ret) 7470 return ret; 7471 7472 ret = __netdev_adjacent_dev_link_neighbour(dev, upper_dev, upper_priv, 7473 master); 7474 if (ret) 7475 return ret; 7476 7477 ret = call_netdevice_notifiers_info(NETDEV_CHANGEUPPER, 7478 &changeupper_info.info); 7479 ret = notifier_to_errno(ret); 7480 if (ret) 7481 goto rollback; 7482 7483 __netdev_update_upper_level(dev, NULL); 7484 __netdev_walk_all_lower_dev(dev, __netdev_update_upper_level, NULL); 7485 7486 __netdev_update_lower_level(upper_dev, priv); 7487 __netdev_walk_all_upper_dev(upper_dev, __netdev_update_lower_level, 7488 priv); 7489 7490 return 0; 7491 7492 rollback: 7493 __netdev_adjacent_dev_unlink_neighbour(dev, upper_dev); 7494 7495 return ret; 7496 } 7497 7498 /** 7499 * netdev_upper_dev_link - Add a link to the upper device 7500 * @dev: device 7501 * @upper_dev: new upper device 7502 * @extack: netlink extended ack 7503 * 7504 * Adds a link to device which is upper to this one. The caller must hold 7505 * the RTNL lock. On a failure a negative errno code is returned. 7506 * On success the reference counts are adjusted and the function 7507 * returns zero. 7508 */ 7509 int netdev_upper_dev_link(struct net_device *dev, 7510 struct net_device *upper_dev, 7511 struct netlink_ext_ack *extack) 7512 { 7513 struct netdev_nested_priv priv = { 7514 .flags = NESTED_SYNC_IMM | NESTED_SYNC_TODO, 7515 .data = NULL, 7516 }; 7517 7518 return __netdev_upper_dev_link(dev, upper_dev, false, 7519 NULL, NULL, &priv, extack); 7520 } 7521 EXPORT_SYMBOL(netdev_upper_dev_link); 7522 7523 /** 7524 * netdev_master_upper_dev_link - Add a master link to the upper device 7525 * @dev: device 7526 * @upper_dev: new upper device 7527 * @upper_priv: upper device private 7528 * @upper_info: upper info to be passed down via notifier 7529 * @extack: netlink extended ack 7530 * 7531 * Adds a link to device which is upper to this one. In this case, only 7532 * one master upper device can be linked, although other non-master devices 7533 * might be linked as well. The caller must hold the RTNL lock. 7534 * On a failure a negative errno code is returned. On success the reference 7535 * counts are adjusted and the function returns zero. 7536 */ 7537 int netdev_master_upper_dev_link(struct net_device *dev, 7538 struct net_device *upper_dev, 7539 void *upper_priv, void *upper_info, 7540 struct netlink_ext_ack *extack) 7541 { 7542 struct netdev_nested_priv priv = { 7543 .flags = NESTED_SYNC_IMM | NESTED_SYNC_TODO, 7544 .data = NULL, 7545 }; 7546 7547 return __netdev_upper_dev_link(dev, upper_dev, true, 7548 upper_priv, upper_info, &priv, extack); 7549 } 7550 EXPORT_SYMBOL(netdev_master_upper_dev_link); 7551 7552 static void __netdev_upper_dev_unlink(struct net_device *dev, 7553 struct net_device *upper_dev, 7554 struct netdev_nested_priv *priv) 7555 { 7556 struct netdev_notifier_changeupper_info changeupper_info = { 7557 .info = { 7558 .dev = dev, 7559 }, 7560 .upper_dev = upper_dev, 7561 .linking = false, 7562 }; 7563 7564 ASSERT_RTNL(); 7565 7566 changeupper_info.master = netdev_master_upper_dev_get(dev) == upper_dev; 7567 7568 call_netdevice_notifiers_info(NETDEV_PRECHANGEUPPER, 7569 &changeupper_info.info); 7570 7571 __netdev_adjacent_dev_unlink_neighbour(dev, upper_dev); 7572 7573 call_netdevice_notifiers_info(NETDEV_CHANGEUPPER, 7574 &changeupper_info.info); 7575 7576 __netdev_update_upper_level(dev, NULL); 7577 __netdev_walk_all_lower_dev(dev, __netdev_update_upper_level, NULL); 7578 7579 __netdev_update_lower_level(upper_dev, priv); 7580 __netdev_walk_all_upper_dev(upper_dev, __netdev_update_lower_level, 7581 priv); 7582 } 7583 7584 /** 7585 * netdev_upper_dev_unlink - Removes a link to upper device 7586 * @dev: device 7587 * @upper_dev: new upper device 7588 * 7589 * Removes a link to device which is upper to this one. The caller must hold 7590 * the RTNL lock. 7591 */ 7592 void netdev_upper_dev_unlink(struct net_device *dev, 7593 struct net_device *upper_dev) 7594 { 7595 struct netdev_nested_priv priv = { 7596 .flags = NESTED_SYNC_TODO, 7597 .data = NULL, 7598 }; 7599 7600 __netdev_upper_dev_unlink(dev, upper_dev, &priv); 7601 } 7602 EXPORT_SYMBOL(netdev_upper_dev_unlink); 7603 7604 static void __netdev_adjacent_dev_set(struct net_device *upper_dev, 7605 struct net_device *lower_dev, 7606 bool val) 7607 { 7608 struct netdev_adjacent *adj; 7609 7610 adj = __netdev_find_adj(lower_dev, &upper_dev->adj_list.lower); 7611 if (adj) 7612 adj->ignore = val; 7613 7614 adj = __netdev_find_adj(upper_dev, &lower_dev->adj_list.upper); 7615 if (adj) 7616 adj->ignore = val; 7617 } 7618 7619 static void netdev_adjacent_dev_disable(struct net_device *upper_dev, 7620 struct net_device *lower_dev) 7621 { 7622 __netdev_adjacent_dev_set(upper_dev, lower_dev, true); 7623 } 7624 7625 static void netdev_adjacent_dev_enable(struct net_device *upper_dev, 7626 struct net_device *lower_dev) 7627 { 7628 __netdev_adjacent_dev_set(upper_dev, lower_dev, false); 7629 } 7630 7631 int netdev_adjacent_change_prepare(struct net_device *old_dev, 7632 struct net_device *new_dev, 7633 struct net_device *dev, 7634 struct netlink_ext_ack *extack) 7635 { 7636 struct netdev_nested_priv priv = { 7637 .flags = 0, 7638 .data = NULL, 7639 }; 7640 int err; 7641 7642 if (!new_dev) 7643 return 0; 7644 7645 if (old_dev && new_dev != old_dev) 7646 netdev_adjacent_dev_disable(dev, old_dev); 7647 err = __netdev_upper_dev_link(new_dev, dev, false, NULL, NULL, &priv, 7648 extack); 7649 if (err) { 7650 if (old_dev && new_dev != old_dev) 7651 netdev_adjacent_dev_enable(dev, old_dev); 7652 return err; 7653 } 7654 7655 return 0; 7656 } 7657 EXPORT_SYMBOL(netdev_adjacent_change_prepare); 7658 7659 void netdev_adjacent_change_commit(struct net_device *old_dev, 7660 struct net_device *new_dev, 7661 struct net_device *dev) 7662 { 7663 struct netdev_nested_priv priv = { 7664 .flags = NESTED_SYNC_IMM | NESTED_SYNC_TODO, 7665 .data = NULL, 7666 }; 7667 7668 if (!new_dev || !old_dev) 7669 return; 7670 7671 if (new_dev == old_dev) 7672 return; 7673 7674 netdev_adjacent_dev_enable(dev, old_dev); 7675 __netdev_upper_dev_unlink(old_dev, dev, &priv); 7676 } 7677 EXPORT_SYMBOL(netdev_adjacent_change_commit); 7678 7679 void netdev_adjacent_change_abort(struct net_device *old_dev, 7680 struct net_device *new_dev, 7681 struct net_device *dev) 7682 { 7683 struct netdev_nested_priv priv = { 7684 .flags = 0, 7685 .data = NULL, 7686 }; 7687 7688 if (!new_dev) 7689 return; 7690 7691 if (old_dev && new_dev != old_dev) 7692 netdev_adjacent_dev_enable(dev, old_dev); 7693 7694 __netdev_upper_dev_unlink(new_dev, dev, &priv); 7695 } 7696 EXPORT_SYMBOL(netdev_adjacent_change_abort); 7697 7698 /** 7699 * netdev_bonding_info_change - Dispatch event about slave change 7700 * @dev: device 7701 * @bonding_info: info to dispatch 7702 * 7703 * Send NETDEV_BONDING_INFO to netdev notifiers with info. 7704 * The caller must hold the RTNL lock. 7705 */ 7706 void netdev_bonding_info_change(struct net_device *dev, 7707 struct netdev_bonding_info *bonding_info) 7708 { 7709 struct netdev_notifier_bonding_info info = { 7710 .info.dev = dev, 7711 }; 7712 7713 memcpy(&info.bonding_info, bonding_info, 7714 sizeof(struct netdev_bonding_info)); 7715 call_netdevice_notifiers_info(NETDEV_BONDING_INFO, 7716 &info.info); 7717 } 7718 EXPORT_SYMBOL(netdev_bonding_info_change); 7719 7720 /** 7721 * netdev_get_xmit_slave - Get the xmit slave of master device 7722 * @dev: device 7723 * @skb: The packet 7724 * @all_slaves: assume all the slaves are active 7725 * 7726 * The reference counters are not incremented so the caller must be 7727 * careful with locks. The caller must hold RCU lock. 7728 * %NULL is returned if no slave is found. 7729 */ 7730 7731 struct net_device *netdev_get_xmit_slave(struct net_device *dev, 7732 struct sk_buff *skb, 7733 bool all_slaves) 7734 { 7735 const struct net_device_ops *ops = dev->netdev_ops; 7736 7737 if (!ops->ndo_get_xmit_slave) 7738 return NULL; 7739 return ops->ndo_get_xmit_slave(dev, skb, all_slaves); 7740 } 7741 EXPORT_SYMBOL(netdev_get_xmit_slave); 7742 7743 static struct net_device *netdev_sk_get_lower_dev(struct net_device *dev, 7744 struct sock *sk) 7745 { 7746 const struct net_device_ops *ops = dev->netdev_ops; 7747 7748 if (!ops->ndo_sk_get_lower_dev) 7749 return NULL; 7750 return ops->ndo_sk_get_lower_dev(dev, sk); 7751 } 7752 7753 /** 7754 * netdev_sk_get_lowest_dev - Get the lowest device in chain given device and socket 7755 * @dev: device 7756 * @sk: the socket 7757 * 7758 * %NULL is returned if no lower device is found. 7759 */ 7760 7761 struct net_device *netdev_sk_get_lowest_dev(struct net_device *dev, 7762 struct sock *sk) 7763 { 7764 struct net_device *lower; 7765 7766 lower = netdev_sk_get_lower_dev(dev, sk); 7767 while (lower) { 7768 dev = lower; 7769 lower = netdev_sk_get_lower_dev(dev, sk); 7770 } 7771 7772 return dev; 7773 } 7774 EXPORT_SYMBOL(netdev_sk_get_lowest_dev); 7775 7776 static void netdev_adjacent_add_links(struct net_device *dev) 7777 { 7778 struct netdev_adjacent *iter; 7779 7780 struct net *net = dev_net(dev); 7781 7782 list_for_each_entry(iter, &dev->adj_list.upper, list) { 7783 if (!net_eq(net, dev_net(iter->dev))) 7784 continue; 7785 netdev_adjacent_sysfs_add(iter->dev, dev, 7786 &iter->dev->adj_list.lower); 7787 netdev_adjacent_sysfs_add(dev, iter->dev, 7788 &dev->adj_list.upper); 7789 } 7790 7791 list_for_each_entry(iter, &dev->adj_list.lower, list) { 7792 if (!net_eq(net, dev_net(iter->dev))) 7793 continue; 7794 netdev_adjacent_sysfs_add(iter->dev, dev, 7795 &iter->dev->adj_list.upper); 7796 netdev_adjacent_sysfs_add(dev, iter->dev, 7797 &dev->adj_list.lower); 7798 } 7799 } 7800 7801 static void netdev_adjacent_del_links(struct net_device *dev) 7802 { 7803 struct netdev_adjacent *iter; 7804 7805 struct net *net = dev_net(dev); 7806 7807 list_for_each_entry(iter, &dev->adj_list.upper, list) { 7808 if (!net_eq(net, dev_net(iter->dev))) 7809 continue; 7810 netdev_adjacent_sysfs_del(iter->dev, dev->name, 7811 &iter->dev->adj_list.lower); 7812 netdev_adjacent_sysfs_del(dev, iter->dev->name, 7813 &dev->adj_list.upper); 7814 } 7815 7816 list_for_each_entry(iter, &dev->adj_list.lower, list) { 7817 if (!net_eq(net, dev_net(iter->dev))) 7818 continue; 7819 netdev_adjacent_sysfs_del(iter->dev, dev->name, 7820 &iter->dev->adj_list.upper); 7821 netdev_adjacent_sysfs_del(dev, iter->dev->name, 7822 &dev->adj_list.lower); 7823 } 7824 } 7825 7826 void netdev_adjacent_rename_links(struct net_device *dev, char *oldname) 7827 { 7828 struct netdev_adjacent *iter; 7829 7830 struct net *net = dev_net(dev); 7831 7832 list_for_each_entry(iter, &dev->adj_list.upper, list) { 7833 if (!net_eq(net, dev_net(iter->dev))) 7834 continue; 7835 netdev_adjacent_sysfs_del(iter->dev, oldname, 7836 &iter->dev->adj_list.lower); 7837 netdev_adjacent_sysfs_add(iter->dev, dev, 7838 &iter->dev->adj_list.lower); 7839 } 7840 7841 list_for_each_entry(iter, &dev->adj_list.lower, list) { 7842 if (!net_eq(net, dev_net(iter->dev))) 7843 continue; 7844 netdev_adjacent_sysfs_del(iter->dev, oldname, 7845 &iter->dev->adj_list.upper); 7846 netdev_adjacent_sysfs_add(iter->dev, dev, 7847 &iter->dev->adj_list.upper); 7848 } 7849 } 7850 7851 void *netdev_lower_dev_get_private(struct net_device *dev, 7852 struct net_device *lower_dev) 7853 { 7854 struct netdev_adjacent *lower; 7855 7856 if (!lower_dev) 7857 return NULL; 7858 lower = __netdev_find_adj(lower_dev, &dev->adj_list.lower); 7859 if (!lower) 7860 return NULL; 7861 7862 return lower->private; 7863 } 7864 EXPORT_SYMBOL(netdev_lower_dev_get_private); 7865 7866 7867 /** 7868 * netdev_lower_state_changed - Dispatch event about lower device state change 7869 * @lower_dev: device 7870 * @lower_state_info: state to dispatch 7871 * 7872 * Send NETDEV_CHANGELOWERSTATE to netdev notifiers with info. 7873 * The caller must hold the RTNL lock. 7874 */ 7875 void netdev_lower_state_changed(struct net_device *lower_dev, 7876 void *lower_state_info) 7877 { 7878 struct netdev_notifier_changelowerstate_info changelowerstate_info = { 7879 .info.dev = lower_dev, 7880 }; 7881 7882 ASSERT_RTNL(); 7883 changelowerstate_info.lower_state_info = lower_state_info; 7884 call_netdevice_notifiers_info(NETDEV_CHANGELOWERSTATE, 7885 &changelowerstate_info.info); 7886 } 7887 EXPORT_SYMBOL(netdev_lower_state_changed); 7888 7889 static void dev_change_rx_flags(struct net_device *dev, int flags) 7890 { 7891 const struct net_device_ops *ops = dev->netdev_ops; 7892 7893 if (ops->ndo_change_rx_flags) 7894 ops->ndo_change_rx_flags(dev, flags); 7895 } 7896 7897 static int __dev_set_promiscuity(struct net_device *dev, int inc, bool notify) 7898 { 7899 unsigned int old_flags = dev->flags; 7900 kuid_t uid; 7901 kgid_t gid; 7902 7903 ASSERT_RTNL(); 7904 7905 dev->flags |= IFF_PROMISC; 7906 dev->promiscuity += inc; 7907 if (dev->promiscuity == 0) { 7908 /* 7909 * Avoid overflow. 7910 * If inc causes overflow, untouch promisc and return error. 7911 */ 7912 if (inc < 0) 7913 dev->flags &= ~IFF_PROMISC; 7914 else { 7915 dev->promiscuity -= inc; 7916 netdev_warn(dev, "promiscuity touches roof, set promiscuity failed. promiscuity feature of device might be broken.\n"); 7917 return -EOVERFLOW; 7918 } 7919 } 7920 if (dev->flags != old_flags) { 7921 pr_info("device %s %s promiscuous mode\n", 7922 dev->name, 7923 dev->flags & IFF_PROMISC ? "entered" : "left"); 7924 if (audit_enabled) { 7925 current_uid_gid(&uid, &gid); 7926 audit_log(audit_context(), GFP_ATOMIC, 7927 AUDIT_ANOM_PROMISCUOUS, 7928 "dev=%s prom=%d old_prom=%d auid=%u uid=%u gid=%u ses=%u", 7929 dev->name, (dev->flags & IFF_PROMISC), 7930 (old_flags & IFF_PROMISC), 7931 from_kuid(&init_user_ns, audit_get_loginuid(current)), 7932 from_kuid(&init_user_ns, uid), 7933 from_kgid(&init_user_ns, gid), 7934 audit_get_sessionid(current)); 7935 } 7936 7937 dev_change_rx_flags(dev, IFF_PROMISC); 7938 } 7939 if (notify) 7940 __dev_notify_flags(dev, old_flags, IFF_PROMISC); 7941 return 0; 7942 } 7943 7944 /** 7945 * dev_set_promiscuity - update promiscuity count on a device 7946 * @dev: device 7947 * @inc: modifier 7948 * 7949 * Add or remove promiscuity from a device. While the count in the device 7950 * remains above zero the interface remains promiscuous. Once it hits zero 7951 * the device reverts back to normal filtering operation. A negative inc 7952 * value is used to drop promiscuity on the device. 7953 * Return 0 if successful or a negative errno code on error. 7954 */ 7955 int dev_set_promiscuity(struct net_device *dev, int inc) 7956 { 7957 unsigned int old_flags = dev->flags; 7958 int err; 7959 7960 err = __dev_set_promiscuity(dev, inc, true); 7961 if (err < 0) 7962 return err; 7963 if (dev->flags != old_flags) 7964 dev_set_rx_mode(dev); 7965 return err; 7966 } 7967 EXPORT_SYMBOL(dev_set_promiscuity); 7968 7969 static int __dev_set_allmulti(struct net_device *dev, int inc, bool notify) 7970 { 7971 unsigned int old_flags = dev->flags, old_gflags = dev->gflags; 7972 7973 ASSERT_RTNL(); 7974 7975 dev->flags |= IFF_ALLMULTI; 7976 dev->allmulti += inc; 7977 if (dev->allmulti == 0) { 7978 /* 7979 * Avoid overflow. 7980 * If inc causes overflow, untouch allmulti and return error. 7981 */ 7982 if (inc < 0) 7983 dev->flags &= ~IFF_ALLMULTI; 7984 else { 7985 dev->allmulti -= inc; 7986 netdev_warn(dev, "allmulti touches roof, set allmulti failed. allmulti feature of device might be broken.\n"); 7987 return -EOVERFLOW; 7988 } 7989 } 7990 if (dev->flags ^ old_flags) { 7991 dev_change_rx_flags(dev, IFF_ALLMULTI); 7992 dev_set_rx_mode(dev); 7993 if (notify) 7994 __dev_notify_flags(dev, old_flags, 7995 dev->gflags ^ old_gflags); 7996 } 7997 return 0; 7998 } 7999 8000 /** 8001 * dev_set_allmulti - update allmulti count on a device 8002 * @dev: device 8003 * @inc: modifier 8004 * 8005 * Add or remove reception of all multicast frames to a device. While the 8006 * count in the device remains above zero the interface remains listening 8007 * to all interfaces. Once it hits zero the device reverts back to normal 8008 * filtering operation. A negative @inc value is used to drop the counter 8009 * when releasing a resource needing all multicasts. 8010 * Return 0 if successful or a negative errno code on error. 8011 */ 8012 8013 int dev_set_allmulti(struct net_device *dev, int inc) 8014 { 8015 return __dev_set_allmulti(dev, inc, true); 8016 } 8017 EXPORT_SYMBOL(dev_set_allmulti); 8018 8019 /* 8020 * Upload unicast and multicast address lists to device and 8021 * configure RX filtering. When the device doesn't support unicast 8022 * filtering it is put in promiscuous mode while unicast addresses 8023 * are present. 8024 */ 8025 void __dev_set_rx_mode(struct net_device *dev) 8026 { 8027 const struct net_device_ops *ops = dev->netdev_ops; 8028 8029 /* dev_open will call this function so the list will stay sane. */ 8030 if (!(dev->flags&IFF_UP)) 8031 return; 8032 8033 if (!netif_device_present(dev)) 8034 return; 8035 8036 if (!(dev->priv_flags & IFF_UNICAST_FLT)) { 8037 /* Unicast addresses changes may only happen under the rtnl, 8038 * therefore calling __dev_set_promiscuity here is safe. 8039 */ 8040 if (!netdev_uc_empty(dev) && !dev->uc_promisc) { 8041 __dev_set_promiscuity(dev, 1, false); 8042 dev->uc_promisc = true; 8043 } else if (netdev_uc_empty(dev) && dev->uc_promisc) { 8044 __dev_set_promiscuity(dev, -1, false); 8045 dev->uc_promisc = false; 8046 } 8047 } 8048 8049 if (ops->ndo_set_rx_mode) 8050 ops->ndo_set_rx_mode(dev); 8051 } 8052 8053 void dev_set_rx_mode(struct net_device *dev) 8054 { 8055 netif_addr_lock_bh(dev); 8056 __dev_set_rx_mode(dev); 8057 netif_addr_unlock_bh(dev); 8058 } 8059 8060 /** 8061 * dev_get_flags - get flags reported to userspace 8062 * @dev: device 8063 * 8064 * Get the combination of flag bits exported through APIs to userspace. 8065 */ 8066 unsigned int dev_get_flags(const struct net_device *dev) 8067 { 8068 unsigned int flags; 8069 8070 flags = (dev->flags & ~(IFF_PROMISC | 8071 IFF_ALLMULTI | 8072 IFF_RUNNING | 8073 IFF_LOWER_UP | 8074 IFF_DORMANT)) | 8075 (dev->gflags & (IFF_PROMISC | 8076 IFF_ALLMULTI)); 8077 8078 if (netif_running(dev)) { 8079 if (netif_oper_up(dev)) 8080 flags |= IFF_RUNNING; 8081 if (netif_carrier_ok(dev)) 8082 flags |= IFF_LOWER_UP; 8083 if (netif_dormant(dev)) 8084 flags |= IFF_DORMANT; 8085 } 8086 8087 return flags; 8088 } 8089 EXPORT_SYMBOL(dev_get_flags); 8090 8091 int __dev_change_flags(struct net_device *dev, unsigned int flags, 8092 struct netlink_ext_ack *extack) 8093 { 8094 unsigned int old_flags = dev->flags; 8095 int ret; 8096 8097 ASSERT_RTNL(); 8098 8099 /* 8100 * Set the flags on our device. 8101 */ 8102 8103 dev->flags = (flags & (IFF_DEBUG | IFF_NOTRAILERS | IFF_NOARP | 8104 IFF_DYNAMIC | IFF_MULTICAST | IFF_PORTSEL | 8105 IFF_AUTOMEDIA)) | 8106 (dev->flags & (IFF_UP | IFF_VOLATILE | IFF_PROMISC | 8107 IFF_ALLMULTI)); 8108 8109 /* 8110 * Load in the correct multicast list now the flags have changed. 8111 */ 8112 8113 if ((old_flags ^ flags) & IFF_MULTICAST) 8114 dev_change_rx_flags(dev, IFF_MULTICAST); 8115 8116 dev_set_rx_mode(dev); 8117 8118 /* 8119 * Have we downed the interface. We handle IFF_UP ourselves 8120 * according to user attempts to set it, rather than blindly 8121 * setting it. 8122 */ 8123 8124 ret = 0; 8125 if ((old_flags ^ flags) & IFF_UP) { 8126 if (old_flags & IFF_UP) 8127 __dev_close(dev); 8128 else 8129 ret = __dev_open(dev, extack); 8130 } 8131 8132 if ((flags ^ dev->gflags) & IFF_PROMISC) { 8133 int inc = (flags & IFF_PROMISC) ? 1 : -1; 8134 unsigned int old_flags = dev->flags; 8135 8136 dev->gflags ^= IFF_PROMISC; 8137 8138 if (__dev_set_promiscuity(dev, inc, false) >= 0) 8139 if (dev->flags != old_flags) 8140 dev_set_rx_mode(dev); 8141 } 8142 8143 /* NOTE: order of synchronization of IFF_PROMISC and IFF_ALLMULTI 8144 * is important. Some (broken) drivers set IFF_PROMISC, when 8145 * IFF_ALLMULTI is requested not asking us and not reporting. 8146 */ 8147 if ((flags ^ dev->gflags) & IFF_ALLMULTI) { 8148 int inc = (flags & IFF_ALLMULTI) ? 1 : -1; 8149 8150 dev->gflags ^= IFF_ALLMULTI; 8151 __dev_set_allmulti(dev, inc, false); 8152 } 8153 8154 return ret; 8155 } 8156 8157 void __dev_notify_flags(struct net_device *dev, unsigned int old_flags, 8158 unsigned int gchanges) 8159 { 8160 unsigned int changes = dev->flags ^ old_flags; 8161 8162 if (gchanges) 8163 rtmsg_ifinfo(RTM_NEWLINK, dev, gchanges, GFP_ATOMIC); 8164 8165 if (changes & IFF_UP) { 8166 if (dev->flags & IFF_UP) 8167 call_netdevice_notifiers(NETDEV_UP, dev); 8168 else 8169 call_netdevice_notifiers(NETDEV_DOWN, dev); 8170 } 8171 8172 if (dev->flags & IFF_UP && 8173 (changes & ~(IFF_UP | IFF_PROMISC | IFF_ALLMULTI | IFF_VOLATILE))) { 8174 struct netdev_notifier_change_info change_info = { 8175 .info = { 8176 .dev = dev, 8177 }, 8178 .flags_changed = changes, 8179 }; 8180 8181 call_netdevice_notifiers_info(NETDEV_CHANGE, &change_info.info); 8182 } 8183 } 8184 8185 /** 8186 * dev_change_flags - change device settings 8187 * @dev: device 8188 * @flags: device state flags 8189 * @extack: netlink extended ack 8190 * 8191 * Change settings on device based state flags. The flags are 8192 * in the userspace exported format. 8193 */ 8194 int dev_change_flags(struct net_device *dev, unsigned int flags, 8195 struct netlink_ext_ack *extack) 8196 { 8197 int ret; 8198 unsigned int changes, old_flags = dev->flags, old_gflags = dev->gflags; 8199 8200 ret = __dev_change_flags(dev, flags, extack); 8201 if (ret < 0) 8202 return ret; 8203 8204 changes = (old_flags ^ dev->flags) | (old_gflags ^ dev->gflags); 8205 __dev_notify_flags(dev, old_flags, changes); 8206 return ret; 8207 } 8208 EXPORT_SYMBOL(dev_change_flags); 8209 8210 int __dev_set_mtu(struct net_device *dev, int new_mtu) 8211 { 8212 const struct net_device_ops *ops = dev->netdev_ops; 8213 8214 if (ops->ndo_change_mtu) 8215 return ops->ndo_change_mtu(dev, new_mtu); 8216 8217 /* Pairs with all the lockless reads of dev->mtu in the stack */ 8218 WRITE_ONCE(dev->mtu, new_mtu); 8219 return 0; 8220 } 8221 EXPORT_SYMBOL(__dev_set_mtu); 8222 8223 int dev_validate_mtu(struct net_device *dev, int new_mtu, 8224 struct netlink_ext_ack *extack) 8225 { 8226 /* MTU must be positive, and in range */ 8227 if (new_mtu < 0 || new_mtu < dev->min_mtu) { 8228 NL_SET_ERR_MSG(extack, "mtu less than device minimum"); 8229 return -EINVAL; 8230 } 8231 8232 if (dev->max_mtu > 0 && new_mtu > dev->max_mtu) { 8233 NL_SET_ERR_MSG(extack, "mtu greater than device maximum"); 8234 return -EINVAL; 8235 } 8236 return 0; 8237 } 8238 8239 /** 8240 * dev_set_mtu_ext - Change maximum transfer unit 8241 * @dev: device 8242 * @new_mtu: new transfer unit 8243 * @extack: netlink extended ack 8244 * 8245 * Change the maximum transfer size of the network device. 8246 */ 8247 int dev_set_mtu_ext(struct net_device *dev, int new_mtu, 8248 struct netlink_ext_ack *extack) 8249 { 8250 int err, orig_mtu; 8251 8252 if (new_mtu == dev->mtu) 8253 return 0; 8254 8255 err = dev_validate_mtu(dev, new_mtu, extack); 8256 if (err) 8257 return err; 8258 8259 if (!netif_device_present(dev)) 8260 return -ENODEV; 8261 8262 err = call_netdevice_notifiers(NETDEV_PRECHANGEMTU, dev); 8263 err = notifier_to_errno(err); 8264 if (err) 8265 return err; 8266 8267 orig_mtu = dev->mtu; 8268 err = __dev_set_mtu(dev, new_mtu); 8269 8270 if (!err) { 8271 err = call_netdevice_notifiers_mtu(NETDEV_CHANGEMTU, dev, 8272 orig_mtu); 8273 err = notifier_to_errno(err); 8274 if (err) { 8275 /* setting mtu back and notifying everyone again, 8276 * so that they have a chance to revert changes. 8277 */ 8278 __dev_set_mtu(dev, orig_mtu); 8279 call_netdevice_notifiers_mtu(NETDEV_CHANGEMTU, dev, 8280 new_mtu); 8281 } 8282 } 8283 return err; 8284 } 8285 8286 int dev_set_mtu(struct net_device *dev, int new_mtu) 8287 { 8288 struct netlink_ext_ack extack; 8289 int err; 8290 8291 memset(&extack, 0, sizeof(extack)); 8292 err = dev_set_mtu_ext(dev, new_mtu, &extack); 8293 if (err && extack._msg) 8294 net_err_ratelimited("%s: %s\n", dev->name, extack._msg); 8295 return err; 8296 } 8297 EXPORT_SYMBOL(dev_set_mtu); 8298 8299 /** 8300 * dev_change_tx_queue_len - Change TX queue length of a netdevice 8301 * @dev: device 8302 * @new_len: new tx queue length 8303 */ 8304 int dev_change_tx_queue_len(struct net_device *dev, unsigned long new_len) 8305 { 8306 unsigned int orig_len = dev->tx_queue_len; 8307 int res; 8308 8309 if (new_len != (unsigned int)new_len) 8310 return -ERANGE; 8311 8312 if (new_len != orig_len) { 8313 dev->tx_queue_len = new_len; 8314 res = call_netdevice_notifiers(NETDEV_CHANGE_TX_QUEUE_LEN, dev); 8315 res = notifier_to_errno(res); 8316 if (res) 8317 goto err_rollback; 8318 res = dev_qdisc_change_tx_queue_len(dev); 8319 if (res) 8320 goto err_rollback; 8321 } 8322 8323 return 0; 8324 8325 err_rollback: 8326 netdev_err(dev, "refused to change device tx_queue_len\n"); 8327 dev->tx_queue_len = orig_len; 8328 return res; 8329 } 8330 8331 /** 8332 * dev_set_group - Change group this device belongs to 8333 * @dev: device 8334 * @new_group: group this device should belong to 8335 */ 8336 void dev_set_group(struct net_device *dev, int new_group) 8337 { 8338 dev->group = new_group; 8339 } 8340 EXPORT_SYMBOL(dev_set_group); 8341 8342 /** 8343 * dev_pre_changeaddr_notify - Call NETDEV_PRE_CHANGEADDR. 8344 * @dev: device 8345 * @addr: new address 8346 * @extack: netlink extended ack 8347 */ 8348 int dev_pre_changeaddr_notify(struct net_device *dev, const char *addr, 8349 struct netlink_ext_ack *extack) 8350 { 8351 struct netdev_notifier_pre_changeaddr_info info = { 8352 .info.dev = dev, 8353 .info.extack = extack, 8354 .dev_addr = addr, 8355 }; 8356 int rc; 8357 8358 rc = call_netdevice_notifiers_info(NETDEV_PRE_CHANGEADDR, &info.info); 8359 return notifier_to_errno(rc); 8360 } 8361 EXPORT_SYMBOL(dev_pre_changeaddr_notify); 8362 8363 /** 8364 * dev_set_mac_address - Change Media Access Control Address 8365 * @dev: device 8366 * @sa: new address 8367 * @extack: netlink extended ack 8368 * 8369 * Change the hardware (MAC) address of the device 8370 */ 8371 int dev_set_mac_address(struct net_device *dev, struct sockaddr *sa, 8372 struct netlink_ext_ack *extack) 8373 { 8374 const struct net_device_ops *ops = dev->netdev_ops; 8375 int err; 8376 8377 if (!ops->ndo_set_mac_address) 8378 return -EOPNOTSUPP; 8379 if (sa->sa_family != dev->type) 8380 return -EINVAL; 8381 if (!netif_device_present(dev)) 8382 return -ENODEV; 8383 err = dev_pre_changeaddr_notify(dev, sa->sa_data, extack); 8384 if (err) 8385 return err; 8386 err = ops->ndo_set_mac_address(dev, sa); 8387 if (err) 8388 return err; 8389 dev->addr_assign_type = NET_ADDR_SET; 8390 call_netdevice_notifiers(NETDEV_CHANGEADDR, dev); 8391 add_device_randomness(dev->dev_addr, dev->addr_len); 8392 return 0; 8393 } 8394 EXPORT_SYMBOL(dev_set_mac_address); 8395 8396 static DECLARE_RWSEM(dev_addr_sem); 8397 8398 int dev_set_mac_address_user(struct net_device *dev, struct sockaddr *sa, 8399 struct netlink_ext_ack *extack) 8400 { 8401 int ret; 8402 8403 down_write(&dev_addr_sem); 8404 ret = dev_set_mac_address(dev, sa, extack); 8405 up_write(&dev_addr_sem); 8406 return ret; 8407 } 8408 EXPORT_SYMBOL(dev_set_mac_address_user); 8409 8410 int dev_get_mac_address(struct sockaddr *sa, struct net *net, char *dev_name) 8411 { 8412 size_t size = sizeof(sa->sa_data); 8413 struct net_device *dev; 8414 int ret = 0; 8415 8416 down_read(&dev_addr_sem); 8417 rcu_read_lock(); 8418 8419 dev = dev_get_by_name_rcu(net, dev_name); 8420 if (!dev) { 8421 ret = -ENODEV; 8422 goto unlock; 8423 } 8424 if (!dev->addr_len) 8425 memset(sa->sa_data, 0, size); 8426 else 8427 memcpy(sa->sa_data, dev->dev_addr, 8428 min_t(size_t, size, dev->addr_len)); 8429 sa->sa_family = dev->type; 8430 8431 unlock: 8432 rcu_read_unlock(); 8433 up_read(&dev_addr_sem); 8434 return ret; 8435 } 8436 EXPORT_SYMBOL(dev_get_mac_address); 8437 8438 /** 8439 * dev_change_carrier - Change device carrier 8440 * @dev: device 8441 * @new_carrier: new value 8442 * 8443 * Change device carrier 8444 */ 8445 int dev_change_carrier(struct net_device *dev, bool new_carrier) 8446 { 8447 const struct net_device_ops *ops = dev->netdev_ops; 8448 8449 if (!ops->ndo_change_carrier) 8450 return -EOPNOTSUPP; 8451 if (!netif_device_present(dev)) 8452 return -ENODEV; 8453 return ops->ndo_change_carrier(dev, new_carrier); 8454 } 8455 EXPORT_SYMBOL(dev_change_carrier); 8456 8457 /** 8458 * dev_get_phys_port_id - Get device physical port ID 8459 * @dev: device 8460 * @ppid: port ID 8461 * 8462 * Get device physical port ID 8463 */ 8464 int dev_get_phys_port_id(struct net_device *dev, 8465 struct netdev_phys_item_id *ppid) 8466 { 8467 const struct net_device_ops *ops = dev->netdev_ops; 8468 8469 if (!ops->ndo_get_phys_port_id) 8470 return -EOPNOTSUPP; 8471 return ops->ndo_get_phys_port_id(dev, ppid); 8472 } 8473 EXPORT_SYMBOL(dev_get_phys_port_id); 8474 8475 /** 8476 * dev_get_phys_port_name - Get device physical port name 8477 * @dev: device 8478 * @name: port name 8479 * @len: limit of bytes to copy to name 8480 * 8481 * Get device physical port name 8482 */ 8483 int dev_get_phys_port_name(struct net_device *dev, 8484 char *name, size_t len) 8485 { 8486 const struct net_device_ops *ops = dev->netdev_ops; 8487 int err; 8488 8489 if (ops->ndo_get_phys_port_name) { 8490 err = ops->ndo_get_phys_port_name(dev, name, len); 8491 if (err != -EOPNOTSUPP) 8492 return err; 8493 } 8494 return devlink_compat_phys_port_name_get(dev, name, len); 8495 } 8496 EXPORT_SYMBOL(dev_get_phys_port_name); 8497 8498 /** 8499 * dev_get_port_parent_id - Get the device's port parent identifier 8500 * @dev: network device 8501 * @ppid: pointer to a storage for the port's parent identifier 8502 * @recurse: allow/disallow recursion to lower devices 8503 * 8504 * Get the devices's port parent identifier 8505 */ 8506 int dev_get_port_parent_id(struct net_device *dev, 8507 struct netdev_phys_item_id *ppid, 8508 bool recurse) 8509 { 8510 const struct net_device_ops *ops = dev->netdev_ops; 8511 struct netdev_phys_item_id first = { }; 8512 struct net_device *lower_dev; 8513 struct list_head *iter; 8514 int err; 8515 8516 if (ops->ndo_get_port_parent_id) { 8517 err = ops->ndo_get_port_parent_id(dev, ppid); 8518 if (err != -EOPNOTSUPP) 8519 return err; 8520 } 8521 8522 err = devlink_compat_switch_id_get(dev, ppid); 8523 if (!recurse || err != -EOPNOTSUPP) 8524 return err; 8525 8526 netdev_for_each_lower_dev(dev, lower_dev, iter) { 8527 err = dev_get_port_parent_id(lower_dev, ppid, true); 8528 if (err) 8529 break; 8530 if (!first.id_len) 8531 first = *ppid; 8532 else if (memcmp(&first, ppid, sizeof(*ppid))) 8533 return -EOPNOTSUPP; 8534 } 8535 8536 return err; 8537 } 8538 EXPORT_SYMBOL(dev_get_port_parent_id); 8539 8540 /** 8541 * netdev_port_same_parent_id - Indicate if two network devices have 8542 * the same port parent identifier 8543 * @a: first network device 8544 * @b: second network device 8545 */ 8546 bool netdev_port_same_parent_id(struct net_device *a, struct net_device *b) 8547 { 8548 struct netdev_phys_item_id a_id = { }; 8549 struct netdev_phys_item_id b_id = { }; 8550 8551 if (dev_get_port_parent_id(a, &a_id, true) || 8552 dev_get_port_parent_id(b, &b_id, true)) 8553 return false; 8554 8555 return netdev_phys_item_id_same(&a_id, &b_id); 8556 } 8557 EXPORT_SYMBOL(netdev_port_same_parent_id); 8558 8559 /** 8560 * dev_change_proto_down - update protocol port state information 8561 * @dev: device 8562 * @proto_down: new value 8563 * 8564 * This info can be used by switch drivers to set the phys state of the 8565 * port. 8566 */ 8567 int dev_change_proto_down(struct net_device *dev, bool proto_down) 8568 { 8569 const struct net_device_ops *ops = dev->netdev_ops; 8570 8571 if (!ops->ndo_change_proto_down) 8572 return -EOPNOTSUPP; 8573 if (!netif_device_present(dev)) 8574 return -ENODEV; 8575 return ops->ndo_change_proto_down(dev, proto_down); 8576 } 8577 EXPORT_SYMBOL(dev_change_proto_down); 8578 8579 /** 8580 * dev_change_proto_down_generic - generic implementation for 8581 * ndo_change_proto_down that sets carrier according to 8582 * proto_down. 8583 * 8584 * @dev: device 8585 * @proto_down: new value 8586 */ 8587 int dev_change_proto_down_generic(struct net_device *dev, bool proto_down) 8588 { 8589 if (proto_down) 8590 netif_carrier_off(dev); 8591 else 8592 netif_carrier_on(dev); 8593 dev->proto_down = proto_down; 8594 return 0; 8595 } 8596 EXPORT_SYMBOL(dev_change_proto_down_generic); 8597 8598 /** 8599 * dev_change_proto_down_reason - proto down reason 8600 * 8601 * @dev: device 8602 * @mask: proto down mask 8603 * @value: proto down value 8604 */ 8605 void dev_change_proto_down_reason(struct net_device *dev, unsigned long mask, 8606 u32 value) 8607 { 8608 int b; 8609 8610 if (!mask) { 8611 dev->proto_down_reason = value; 8612 } else { 8613 for_each_set_bit(b, &mask, 32) { 8614 if (value & (1 << b)) 8615 dev->proto_down_reason |= BIT(b); 8616 else 8617 dev->proto_down_reason &= ~BIT(b); 8618 } 8619 } 8620 } 8621 EXPORT_SYMBOL(dev_change_proto_down_reason); 8622 8623 struct bpf_xdp_link { 8624 struct bpf_link link; 8625 struct net_device *dev; /* protected by rtnl_lock, no refcnt held */ 8626 int flags; 8627 }; 8628 8629 static enum bpf_xdp_mode dev_xdp_mode(struct net_device *dev, u32 flags) 8630 { 8631 if (flags & XDP_FLAGS_HW_MODE) 8632 return XDP_MODE_HW; 8633 if (flags & XDP_FLAGS_DRV_MODE) 8634 return XDP_MODE_DRV; 8635 if (flags & XDP_FLAGS_SKB_MODE) 8636 return XDP_MODE_SKB; 8637 return dev->netdev_ops->ndo_bpf ? XDP_MODE_DRV : XDP_MODE_SKB; 8638 } 8639 8640 static bpf_op_t dev_xdp_bpf_op(struct net_device *dev, enum bpf_xdp_mode mode) 8641 { 8642 switch (mode) { 8643 case XDP_MODE_SKB: 8644 return generic_xdp_install; 8645 case XDP_MODE_DRV: 8646 case XDP_MODE_HW: 8647 return dev->netdev_ops->ndo_bpf; 8648 default: 8649 return NULL; 8650 } 8651 } 8652 8653 static struct bpf_xdp_link *dev_xdp_link(struct net_device *dev, 8654 enum bpf_xdp_mode mode) 8655 { 8656 return dev->xdp_state[mode].link; 8657 } 8658 8659 static struct bpf_prog *dev_xdp_prog(struct net_device *dev, 8660 enum bpf_xdp_mode mode) 8661 { 8662 struct bpf_xdp_link *link = dev_xdp_link(dev, mode); 8663 8664 if (link) 8665 return link->link.prog; 8666 return dev->xdp_state[mode].prog; 8667 } 8668 8669 u8 dev_xdp_prog_count(struct net_device *dev) 8670 { 8671 u8 count = 0; 8672 int i; 8673 8674 for (i = 0; i < __MAX_XDP_MODE; i++) 8675 if (dev->xdp_state[i].prog || dev->xdp_state[i].link) 8676 count++; 8677 return count; 8678 } 8679 EXPORT_SYMBOL_GPL(dev_xdp_prog_count); 8680 8681 u32 dev_xdp_prog_id(struct net_device *dev, enum bpf_xdp_mode mode) 8682 { 8683 struct bpf_prog *prog = dev_xdp_prog(dev, mode); 8684 8685 return prog ? prog->aux->id : 0; 8686 } 8687 8688 static void dev_xdp_set_link(struct net_device *dev, enum bpf_xdp_mode mode, 8689 struct bpf_xdp_link *link) 8690 { 8691 dev->xdp_state[mode].link = link; 8692 dev->xdp_state[mode].prog = NULL; 8693 } 8694 8695 static void dev_xdp_set_prog(struct net_device *dev, enum bpf_xdp_mode mode, 8696 struct bpf_prog *prog) 8697 { 8698 dev->xdp_state[mode].link = NULL; 8699 dev->xdp_state[mode].prog = prog; 8700 } 8701 8702 static int dev_xdp_install(struct net_device *dev, enum bpf_xdp_mode mode, 8703 bpf_op_t bpf_op, struct netlink_ext_ack *extack, 8704 u32 flags, struct bpf_prog *prog) 8705 { 8706 struct netdev_bpf xdp; 8707 int err; 8708 8709 memset(&xdp, 0, sizeof(xdp)); 8710 xdp.command = mode == XDP_MODE_HW ? XDP_SETUP_PROG_HW : XDP_SETUP_PROG; 8711 xdp.extack = extack; 8712 xdp.flags = flags; 8713 xdp.prog = prog; 8714 8715 /* Drivers assume refcnt is already incremented (i.e, prog pointer is 8716 * "moved" into driver), so they don't increment it on their own, but 8717 * they do decrement refcnt when program is detached or replaced. 8718 * Given net_device also owns link/prog, we need to bump refcnt here 8719 * to prevent drivers from underflowing it. 8720 */ 8721 if (prog) 8722 bpf_prog_inc(prog); 8723 err = bpf_op(dev, &xdp); 8724 if (err) { 8725 if (prog) 8726 bpf_prog_put(prog); 8727 return err; 8728 } 8729 8730 if (mode != XDP_MODE_HW) 8731 bpf_prog_change_xdp(dev_xdp_prog(dev, mode), prog); 8732 8733 return 0; 8734 } 8735 8736 static void dev_xdp_uninstall(struct net_device *dev) 8737 { 8738 struct bpf_xdp_link *link; 8739 struct bpf_prog *prog; 8740 enum bpf_xdp_mode mode; 8741 bpf_op_t bpf_op; 8742 8743 ASSERT_RTNL(); 8744 8745 for (mode = XDP_MODE_SKB; mode < __MAX_XDP_MODE; mode++) { 8746 prog = dev_xdp_prog(dev, mode); 8747 if (!prog) 8748 continue; 8749 8750 bpf_op = dev_xdp_bpf_op(dev, mode); 8751 if (!bpf_op) 8752 continue; 8753 8754 WARN_ON(dev_xdp_install(dev, mode, bpf_op, NULL, 0, NULL)); 8755 8756 /* auto-detach link from net device */ 8757 link = dev_xdp_link(dev, mode); 8758 if (link) 8759 link->dev = NULL; 8760 else 8761 bpf_prog_put(prog); 8762 8763 dev_xdp_set_link(dev, mode, NULL); 8764 } 8765 } 8766 8767 static int dev_xdp_attach(struct net_device *dev, struct netlink_ext_ack *extack, 8768 struct bpf_xdp_link *link, struct bpf_prog *new_prog, 8769 struct bpf_prog *old_prog, u32 flags) 8770 { 8771 unsigned int num_modes = hweight32(flags & XDP_FLAGS_MODES); 8772 struct bpf_prog *cur_prog; 8773 struct net_device *upper; 8774 struct list_head *iter; 8775 enum bpf_xdp_mode mode; 8776 bpf_op_t bpf_op; 8777 int err; 8778 8779 ASSERT_RTNL(); 8780 8781 /* either link or prog attachment, never both */ 8782 if (link && (new_prog || old_prog)) 8783 return -EINVAL; 8784 /* link supports only XDP mode flags */ 8785 if (link && (flags & ~XDP_FLAGS_MODES)) { 8786 NL_SET_ERR_MSG(extack, "Invalid XDP flags for BPF link attachment"); 8787 return -EINVAL; 8788 } 8789 /* just one XDP mode bit should be set, zero defaults to drv/skb mode */ 8790 if (num_modes > 1) { 8791 NL_SET_ERR_MSG(extack, "Only one XDP mode flag can be set"); 8792 return -EINVAL; 8793 } 8794 /* avoid ambiguity if offload + drv/skb mode progs are both loaded */ 8795 if (!num_modes && dev_xdp_prog_count(dev) > 1) { 8796 NL_SET_ERR_MSG(extack, 8797 "More than one program loaded, unset mode is ambiguous"); 8798 return -EINVAL; 8799 } 8800 /* old_prog != NULL implies XDP_FLAGS_REPLACE is set */ 8801 if (old_prog && !(flags & XDP_FLAGS_REPLACE)) { 8802 NL_SET_ERR_MSG(extack, "XDP_FLAGS_REPLACE is not specified"); 8803 return -EINVAL; 8804 } 8805 8806 mode = dev_xdp_mode(dev, flags); 8807 /* can't replace attached link */ 8808 if (dev_xdp_link(dev, mode)) { 8809 NL_SET_ERR_MSG(extack, "Can't replace active BPF XDP link"); 8810 return -EBUSY; 8811 } 8812 8813 /* don't allow if an upper device already has a program */ 8814 netdev_for_each_upper_dev_rcu(dev, upper, iter) { 8815 if (dev_xdp_prog_count(upper) > 0) { 8816 NL_SET_ERR_MSG(extack, "Cannot attach when an upper device already has a program"); 8817 return -EEXIST; 8818 } 8819 } 8820 8821 cur_prog = dev_xdp_prog(dev, mode); 8822 /* can't replace attached prog with link */ 8823 if (link && cur_prog) { 8824 NL_SET_ERR_MSG(extack, "Can't replace active XDP program with BPF link"); 8825 return -EBUSY; 8826 } 8827 if ((flags & XDP_FLAGS_REPLACE) && cur_prog != old_prog) { 8828 NL_SET_ERR_MSG(extack, "Active program does not match expected"); 8829 return -EEXIST; 8830 } 8831 8832 /* put effective new program into new_prog */ 8833 if (link) 8834 new_prog = link->link.prog; 8835 8836 if (new_prog) { 8837 bool offload = mode == XDP_MODE_HW; 8838 enum bpf_xdp_mode other_mode = mode == XDP_MODE_SKB 8839 ? XDP_MODE_DRV : XDP_MODE_SKB; 8840 8841 if ((flags & XDP_FLAGS_UPDATE_IF_NOEXIST) && cur_prog) { 8842 NL_SET_ERR_MSG(extack, "XDP program already attached"); 8843 return -EBUSY; 8844 } 8845 if (!offload && dev_xdp_prog(dev, other_mode)) { 8846 NL_SET_ERR_MSG(extack, "Native and generic XDP can't be active at the same time"); 8847 return -EEXIST; 8848 } 8849 if (!offload && bpf_prog_is_dev_bound(new_prog->aux)) { 8850 NL_SET_ERR_MSG(extack, "Using device-bound program without HW_MODE flag is not supported"); 8851 return -EINVAL; 8852 } 8853 if (new_prog->expected_attach_type == BPF_XDP_DEVMAP) { 8854 NL_SET_ERR_MSG(extack, "BPF_XDP_DEVMAP programs can not be attached to a device"); 8855 return -EINVAL; 8856 } 8857 if (new_prog->expected_attach_type == BPF_XDP_CPUMAP) { 8858 NL_SET_ERR_MSG(extack, "BPF_XDP_CPUMAP programs can not be attached to a device"); 8859 return -EINVAL; 8860 } 8861 } 8862 8863 /* don't call drivers if the effective program didn't change */ 8864 if (new_prog != cur_prog) { 8865 bpf_op = dev_xdp_bpf_op(dev, mode); 8866 if (!bpf_op) { 8867 NL_SET_ERR_MSG(extack, "Underlying driver does not support XDP in native mode"); 8868 return -EOPNOTSUPP; 8869 } 8870 8871 err = dev_xdp_install(dev, mode, bpf_op, extack, flags, new_prog); 8872 if (err) 8873 return err; 8874 } 8875 8876 if (link) 8877 dev_xdp_set_link(dev, mode, link); 8878 else 8879 dev_xdp_set_prog(dev, mode, new_prog); 8880 if (cur_prog) 8881 bpf_prog_put(cur_prog); 8882 8883 return 0; 8884 } 8885 8886 static int dev_xdp_attach_link(struct net_device *dev, 8887 struct netlink_ext_ack *extack, 8888 struct bpf_xdp_link *link) 8889 { 8890 return dev_xdp_attach(dev, extack, link, NULL, NULL, link->flags); 8891 } 8892 8893 static int dev_xdp_detach_link(struct net_device *dev, 8894 struct netlink_ext_ack *extack, 8895 struct bpf_xdp_link *link) 8896 { 8897 enum bpf_xdp_mode mode; 8898 bpf_op_t bpf_op; 8899 8900 ASSERT_RTNL(); 8901 8902 mode = dev_xdp_mode(dev, link->flags); 8903 if (dev_xdp_link(dev, mode) != link) 8904 return -EINVAL; 8905 8906 bpf_op = dev_xdp_bpf_op(dev, mode); 8907 WARN_ON(dev_xdp_install(dev, mode, bpf_op, NULL, 0, NULL)); 8908 dev_xdp_set_link(dev, mode, NULL); 8909 return 0; 8910 } 8911 8912 static void bpf_xdp_link_release(struct bpf_link *link) 8913 { 8914 struct bpf_xdp_link *xdp_link = container_of(link, struct bpf_xdp_link, link); 8915 8916 rtnl_lock(); 8917 8918 /* if racing with net_device's tear down, xdp_link->dev might be 8919 * already NULL, in which case link was already auto-detached 8920 */ 8921 if (xdp_link->dev) { 8922 WARN_ON(dev_xdp_detach_link(xdp_link->dev, NULL, xdp_link)); 8923 xdp_link->dev = NULL; 8924 } 8925 8926 rtnl_unlock(); 8927 } 8928 8929 static int bpf_xdp_link_detach(struct bpf_link *link) 8930 { 8931 bpf_xdp_link_release(link); 8932 return 0; 8933 } 8934 8935 static void bpf_xdp_link_dealloc(struct bpf_link *link) 8936 { 8937 struct bpf_xdp_link *xdp_link = container_of(link, struct bpf_xdp_link, link); 8938 8939 kfree(xdp_link); 8940 } 8941 8942 static void bpf_xdp_link_show_fdinfo(const struct bpf_link *link, 8943 struct seq_file *seq) 8944 { 8945 struct bpf_xdp_link *xdp_link = container_of(link, struct bpf_xdp_link, link); 8946 u32 ifindex = 0; 8947 8948 rtnl_lock(); 8949 if (xdp_link->dev) 8950 ifindex = xdp_link->dev->ifindex; 8951 rtnl_unlock(); 8952 8953 seq_printf(seq, "ifindex:\t%u\n", ifindex); 8954 } 8955 8956 static int bpf_xdp_link_fill_link_info(const struct bpf_link *link, 8957 struct bpf_link_info *info) 8958 { 8959 struct bpf_xdp_link *xdp_link = container_of(link, struct bpf_xdp_link, link); 8960 u32 ifindex = 0; 8961 8962 rtnl_lock(); 8963 if (xdp_link->dev) 8964 ifindex = xdp_link->dev->ifindex; 8965 rtnl_unlock(); 8966 8967 info->xdp.ifindex = ifindex; 8968 return 0; 8969 } 8970 8971 static int bpf_xdp_link_update(struct bpf_link *link, struct bpf_prog *new_prog, 8972 struct bpf_prog *old_prog) 8973 { 8974 struct bpf_xdp_link *xdp_link = container_of(link, struct bpf_xdp_link, link); 8975 enum bpf_xdp_mode mode; 8976 bpf_op_t bpf_op; 8977 int err = 0; 8978 8979 rtnl_lock(); 8980 8981 /* link might have been auto-released already, so fail */ 8982 if (!xdp_link->dev) { 8983 err = -ENOLINK; 8984 goto out_unlock; 8985 } 8986 8987 if (old_prog && link->prog != old_prog) { 8988 err = -EPERM; 8989 goto out_unlock; 8990 } 8991 old_prog = link->prog; 8992 if (old_prog == new_prog) { 8993 /* no-op, don't disturb drivers */ 8994 bpf_prog_put(new_prog); 8995 goto out_unlock; 8996 } 8997 8998 mode = dev_xdp_mode(xdp_link->dev, xdp_link->flags); 8999 bpf_op = dev_xdp_bpf_op(xdp_link->dev, mode); 9000 err = dev_xdp_install(xdp_link->dev, mode, bpf_op, NULL, 9001 xdp_link->flags, new_prog); 9002 if (err) 9003 goto out_unlock; 9004 9005 old_prog = xchg(&link->prog, new_prog); 9006 bpf_prog_put(old_prog); 9007 9008 out_unlock: 9009 rtnl_unlock(); 9010 return err; 9011 } 9012 9013 static const struct bpf_link_ops bpf_xdp_link_lops = { 9014 .release = bpf_xdp_link_release, 9015 .dealloc = bpf_xdp_link_dealloc, 9016 .detach = bpf_xdp_link_detach, 9017 .show_fdinfo = bpf_xdp_link_show_fdinfo, 9018 .fill_link_info = bpf_xdp_link_fill_link_info, 9019 .update_prog = bpf_xdp_link_update, 9020 }; 9021 9022 int bpf_xdp_link_attach(const union bpf_attr *attr, struct bpf_prog *prog) 9023 { 9024 struct net *net = current->nsproxy->net_ns; 9025 struct bpf_link_primer link_primer; 9026 struct bpf_xdp_link *link; 9027 struct net_device *dev; 9028 int err, fd; 9029 9030 rtnl_lock(); 9031 dev = dev_get_by_index(net, attr->link_create.target_ifindex); 9032 if (!dev) { 9033 rtnl_unlock(); 9034 return -EINVAL; 9035 } 9036 9037 link = kzalloc(sizeof(*link), GFP_USER); 9038 if (!link) { 9039 err = -ENOMEM; 9040 goto unlock; 9041 } 9042 9043 bpf_link_init(&link->link, BPF_LINK_TYPE_XDP, &bpf_xdp_link_lops, prog); 9044 link->dev = dev; 9045 link->flags = attr->link_create.flags; 9046 9047 err = bpf_link_prime(&link->link, &link_primer); 9048 if (err) { 9049 kfree(link); 9050 goto unlock; 9051 } 9052 9053 err = dev_xdp_attach_link(dev, NULL, link); 9054 rtnl_unlock(); 9055 9056 if (err) { 9057 link->dev = NULL; 9058 bpf_link_cleanup(&link_primer); 9059 goto out_put_dev; 9060 } 9061 9062 fd = bpf_link_settle(&link_primer); 9063 /* link itself doesn't hold dev's refcnt to not complicate shutdown */ 9064 dev_put(dev); 9065 return fd; 9066 9067 unlock: 9068 rtnl_unlock(); 9069 9070 out_put_dev: 9071 dev_put(dev); 9072 return err; 9073 } 9074 9075 /** 9076 * dev_change_xdp_fd - set or clear a bpf program for a device rx path 9077 * @dev: device 9078 * @extack: netlink extended ack 9079 * @fd: new program fd or negative value to clear 9080 * @expected_fd: old program fd that userspace expects to replace or clear 9081 * @flags: xdp-related flags 9082 * 9083 * Set or clear a bpf program for a device 9084 */ 9085 int dev_change_xdp_fd(struct net_device *dev, struct netlink_ext_ack *extack, 9086 int fd, int expected_fd, u32 flags) 9087 { 9088 enum bpf_xdp_mode mode = dev_xdp_mode(dev, flags); 9089 struct bpf_prog *new_prog = NULL, *old_prog = NULL; 9090 int err; 9091 9092 ASSERT_RTNL(); 9093 9094 if (fd >= 0) { 9095 new_prog = bpf_prog_get_type_dev(fd, BPF_PROG_TYPE_XDP, 9096 mode != XDP_MODE_SKB); 9097 if (IS_ERR(new_prog)) 9098 return PTR_ERR(new_prog); 9099 } 9100 9101 if (expected_fd >= 0) { 9102 old_prog = bpf_prog_get_type_dev(expected_fd, BPF_PROG_TYPE_XDP, 9103 mode != XDP_MODE_SKB); 9104 if (IS_ERR(old_prog)) { 9105 err = PTR_ERR(old_prog); 9106 old_prog = NULL; 9107 goto err_out; 9108 } 9109 } 9110 9111 err = dev_xdp_attach(dev, extack, NULL, new_prog, old_prog, flags); 9112 9113 err_out: 9114 if (err && new_prog) 9115 bpf_prog_put(new_prog); 9116 if (old_prog) 9117 bpf_prog_put(old_prog); 9118 return err; 9119 } 9120 9121 /** 9122 * dev_new_index - allocate an ifindex 9123 * @net: the applicable net namespace 9124 * 9125 * Returns a suitable unique value for a new device interface 9126 * number. The caller must hold the rtnl semaphore or the 9127 * dev_base_lock to be sure it remains unique. 9128 */ 9129 static int dev_new_index(struct net *net) 9130 { 9131 int ifindex = net->ifindex; 9132 9133 for (;;) { 9134 if (++ifindex <= 0) 9135 ifindex = 1; 9136 if (!__dev_get_by_index(net, ifindex)) 9137 return net->ifindex = ifindex; 9138 } 9139 } 9140 9141 /* Delayed registration/unregisteration */ 9142 static LIST_HEAD(net_todo_list); 9143 DECLARE_WAIT_QUEUE_HEAD(netdev_unregistering_wq); 9144 9145 static void net_set_todo(struct net_device *dev) 9146 { 9147 list_add_tail(&dev->todo_list, &net_todo_list); 9148 dev_net(dev)->dev_unreg_count++; 9149 } 9150 9151 static netdev_features_t netdev_sync_upper_features(struct net_device *lower, 9152 struct net_device *upper, netdev_features_t features) 9153 { 9154 netdev_features_t upper_disables = NETIF_F_UPPER_DISABLES; 9155 netdev_features_t feature; 9156 int feature_bit; 9157 9158 for_each_netdev_feature(upper_disables, feature_bit) { 9159 feature = __NETIF_F_BIT(feature_bit); 9160 if (!(upper->wanted_features & feature) 9161 && (features & feature)) { 9162 netdev_dbg(lower, "Dropping feature %pNF, upper dev %s has it off.\n", 9163 &feature, upper->name); 9164 features &= ~feature; 9165 } 9166 } 9167 9168 return features; 9169 } 9170 9171 static void netdev_sync_lower_features(struct net_device *upper, 9172 struct net_device *lower, netdev_features_t features) 9173 { 9174 netdev_features_t upper_disables = NETIF_F_UPPER_DISABLES; 9175 netdev_features_t feature; 9176 int feature_bit; 9177 9178 for_each_netdev_feature(upper_disables, feature_bit) { 9179 feature = __NETIF_F_BIT(feature_bit); 9180 if (!(features & feature) && (lower->features & feature)) { 9181 netdev_dbg(upper, "Disabling feature %pNF on lower dev %s.\n", 9182 &feature, lower->name); 9183 lower->wanted_features &= ~feature; 9184 __netdev_update_features(lower); 9185 9186 if (unlikely(lower->features & feature)) 9187 netdev_WARN(upper, "failed to disable %pNF on %s!\n", 9188 &feature, lower->name); 9189 else 9190 netdev_features_change(lower); 9191 } 9192 } 9193 } 9194 9195 static netdev_features_t netdev_fix_features(struct net_device *dev, 9196 netdev_features_t features) 9197 { 9198 /* Fix illegal checksum combinations */ 9199 if ((features & NETIF_F_HW_CSUM) && 9200 (features & (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))) { 9201 netdev_warn(dev, "mixed HW and IP checksum settings.\n"); 9202 features &= ~(NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM); 9203 } 9204 9205 /* TSO requires that SG is present as well. */ 9206 if ((features & NETIF_F_ALL_TSO) && !(features & NETIF_F_SG)) { 9207 netdev_dbg(dev, "Dropping TSO features since no SG feature.\n"); 9208 features &= ~NETIF_F_ALL_TSO; 9209 } 9210 9211 if ((features & NETIF_F_TSO) && !(features & NETIF_F_HW_CSUM) && 9212 !(features & NETIF_F_IP_CSUM)) { 9213 netdev_dbg(dev, "Dropping TSO features since no CSUM feature.\n"); 9214 features &= ~NETIF_F_TSO; 9215 features &= ~NETIF_F_TSO_ECN; 9216 } 9217 9218 if ((features & NETIF_F_TSO6) && !(features & NETIF_F_HW_CSUM) && 9219 !(features & NETIF_F_IPV6_CSUM)) { 9220 netdev_dbg(dev, "Dropping TSO6 features since no CSUM feature.\n"); 9221 features &= ~NETIF_F_TSO6; 9222 } 9223 9224 /* TSO with IPv4 ID mangling requires IPv4 TSO be enabled */ 9225 if ((features & NETIF_F_TSO_MANGLEID) && !(features & NETIF_F_TSO)) 9226 features &= ~NETIF_F_TSO_MANGLEID; 9227 9228 /* TSO ECN requires that TSO is present as well. */ 9229 if ((features & NETIF_F_ALL_TSO) == NETIF_F_TSO_ECN) 9230 features &= ~NETIF_F_TSO_ECN; 9231 9232 /* Software GSO depends on SG. */ 9233 if ((features & NETIF_F_GSO) && !(features & NETIF_F_SG)) { 9234 netdev_dbg(dev, "Dropping NETIF_F_GSO since no SG feature.\n"); 9235 features &= ~NETIF_F_GSO; 9236 } 9237 9238 /* GSO partial features require GSO partial be set */ 9239 if ((features & dev->gso_partial_features) && 9240 !(features & NETIF_F_GSO_PARTIAL)) { 9241 netdev_dbg(dev, 9242 "Dropping partially supported GSO features since no GSO partial.\n"); 9243 features &= ~dev->gso_partial_features; 9244 } 9245 9246 if (!(features & NETIF_F_RXCSUM)) { 9247 /* NETIF_F_GRO_HW implies doing RXCSUM since every packet 9248 * successfully merged by hardware must also have the 9249 * checksum verified by hardware. If the user does not 9250 * want to enable RXCSUM, logically, we should disable GRO_HW. 9251 */ 9252 if (features & NETIF_F_GRO_HW) { 9253 netdev_dbg(dev, "Dropping NETIF_F_GRO_HW since no RXCSUM feature.\n"); 9254 features &= ~NETIF_F_GRO_HW; 9255 } 9256 } 9257 9258 /* LRO/HW-GRO features cannot be combined with RX-FCS */ 9259 if (features & NETIF_F_RXFCS) { 9260 if (features & NETIF_F_LRO) { 9261 netdev_dbg(dev, "Dropping LRO feature since RX-FCS is requested.\n"); 9262 features &= ~NETIF_F_LRO; 9263 } 9264 9265 if (features & NETIF_F_GRO_HW) { 9266 netdev_dbg(dev, "Dropping HW-GRO feature since RX-FCS is requested.\n"); 9267 features &= ~NETIF_F_GRO_HW; 9268 } 9269 } 9270 9271 if ((features & NETIF_F_GRO_HW) && (features & NETIF_F_LRO)) { 9272 netdev_dbg(dev, "Dropping LRO feature since HW-GRO is requested.\n"); 9273 features &= ~NETIF_F_LRO; 9274 } 9275 9276 if (features & NETIF_F_HW_TLS_TX) { 9277 bool ip_csum = (features & (NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM)) == 9278 (NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM); 9279 bool hw_csum = features & NETIF_F_HW_CSUM; 9280 9281 if (!ip_csum && !hw_csum) { 9282 netdev_dbg(dev, "Dropping TLS TX HW offload feature since no CSUM feature.\n"); 9283 features &= ~NETIF_F_HW_TLS_TX; 9284 } 9285 } 9286 9287 if ((features & NETIF_F_HW_TLS_RX) && !(features & NETIF_F_RXCSUM)) { 9288 netdev_dbg(dev, "Dropping TLS RX HW offload feature since no RXCSUM feature.\n"); 9289 features &= ~NETIF_F_HW_TLS_RX; 9290 } 9291 9292 return features; 9293 } 9294 9295 int __netdev_update_features(struct net_device *dev) 9296 { 9297 struct net_device *upper, *lower; 9298 netdev_features_t features; 9299 struct list_head *iter; 9300 int err = -1; 9301 9302 ASSERT_RTNL(); 9303 9304 features = netdev_get_wanted_features(dev); 9305 9306 if (dev->netdev_ops->ndo_fix_features) 9307 features = dev->netdev_ops->ndo_fix_features(dev, features); 9308 9309 /* driver might be less strict about feature dependencies */ 9310 features = netdev_fix_features(dev, features); 9311 9312 /* some features can't be enabled if they're off on an upper device */ 9313 netdev_for_each_upper_dev_rcu(dev, upper, iter) 9314 features = netdev_sync_upper_features(dev, upper, features); 9315 9316 if (dev->features == features) 9317 goto sync_lower; 9318 9319 netdev_dbg(dev, "Features changed: %pNF -> %pNF\n", 9320 &dev->features, &features); 9321 9322 if (dev->netdev_ops->ndo_set_features) 9323 err = dev->netdev_ops->ndo_set_features(dev, features); 9324 else 9325 err = 0; 9326 9327 if (unlikely(err < 0)) { 9328 netdev_err(dev, 9329 "set_features() failed (%d); wanted %pNF, left %pNF\n", 9330 err, &features, &dev->features); 9331 /* return non-0 since some features might have changed and 9332 * it's better to fire a spurious notification than miss it 9333 */ 9334 return -1; 9335 } 9336 9337 sync_lower: 9338 /* some features must be disabled on lower devices when disabled 9339 * on an upper device (think: bonding master or bridge) 9340 */ 9341 netdev_for_each_lower_dev(dev, lower, iter) 9342 netdev_sync_lower_features(dev, lower, features); 9343 9344 if (!err) { 9345 netdev_features_t diff = features ^ dev->features; 9346 9347 if (diff & NETIF_F_RX_UDP_TUNNEL_PORT) { 9348 /* udp_tunnel_{get,drop}_rx_info both need 9349 * NETIF_F_RX_UDP_TUNNEL_PORT enabled on the 9350 * device, or they won't do anything. 9351 * Thus we need to update dev->features 9352 * *before* calling udp_tunnel_get_rx_info, 9353 * but *after* calling udp_tunnel_drop_rx_info. 9354 */ 9355 if (features & NETIF_F_RX_UDP_TUNNEL_PORT) { 9356 dev->features = features; 9357 udp_tunnel_get_rx_info(dev); 9358 } else { 9359 udp_tunnel_drop_rx_info(dev); 9360 } 9361 } 9362 9363 if (diff & NETIF_F_HW_VLAN_CTAG_FILTER) { 9364 if (features & NETIF_F_HW_VLAN_CTAG_FILTER) { 9365 dev->features = features; 9366 err |= vlan_get_rx_ctag_filter_info(dev); 9367 } else { 9368 vlan_drop_rx_ctag_filter_info(dev); 9369 } 9370 } 9371 9372 if (diff & NETIF_F_HW_VLAN_STAG_FILTER) { 9373 if (features & NETIF_F_HW_VLAN_STAG_FILTER) { 9374 dev->features = features; 9375 err |= vlan_get_rx_stag_filter_info(dev); 9376 } else { 9377 vlan_drop_rx_stag_filter_info(dev); 9378 } 9379 } 9380 9381 dev->features = features; 9382 } 9383 9384 return err < 0 ? 0 : 1; 9385 } 9386 9387 /** 9388 * netdev_update_features - recalculate device features 9389 * @dev: the device to check 9390 * 9391 * Recalculate dev->features set and send notifications if it 9392 * has changed. Should be called after driver or hardware dependent 9393 * conditions might have changed that influence the features. 9394 */ 9395 void netdev_update_features(struct net_device *dev) 9396 { 9397 if (__netdev_update_features(dev)) 9398 netdev_features_change(dev); 9399 } 9400 EXPORT_SYMBOL(netdev_update_features); 9401 9402 /** 9403 * netdev_change_features - recalculate device features 9404 * @dev: the device to check 9405 * 9406 * Recalculate dev->features set and send notifications even 9407 * if they have not changed. Should be called instead of 9408 * netdev_update_features() if also dev->vlan_features might 9409 * have changed to allow the changes to be propagated to stacked 9410 * VLAN devices. 9411 */ 9412 void netdev_change_features(struct net_device *dev) 9413 { 9414 __netdev_update_features(dev); 9415 netdev_features_change(dev); 9416 } 9417 EXPORT_SYMBOL(netdev_change_features); 9418 9419 /** 9420 * netif_stacked_transfer_operstate - transfer operstate 9421 * @rootdev: the root or lower level device to transfer state from 9422 * @dev: the device to transfer operstate to 9423 * 9424 * Transfer operational state from root to device. This is normally 9425 * called when a stacking relationship exists between the root 9426 * device and the device(a leaf device). 9427 */ 9428 void netif_stacked_transfer_operstate(const struct net_device *rootdev, 9429 struct net_device *dev) 9430 { 9431 if (rootdev->operstate == IF_OPER_DORMANT) 9432 netif_dormant_on(dev); 9433 else 9434 netif_dormant_off(dev); 9435 9436 if (rootdev->operstate == IF_OPER_TESTING) 9437 netif_testing_on(dev); 9438 else 9439 netif_testing_off(dev); 9440 9441 if (netif_carrier_ok(rootdev)) 9442 netif_carrier_on(dev); 9443 else 9444 netif_carrier_off(dev); 9445 } 9446 EXPORT_SYMBOL(netif_stacked_transfer_operstate); 9447 9448 static int netif_alloc_rx_queues(struct net_device *dev) 9449 { 9450 unsigned int i, count = dev->num_rx_queues; 9451 struct netdev_rx_queue *rx; 9452 size_t sz = count * sizeof(*rx); 9453 int err = 0; 9454 9455 BUG_ON(count < 1); 9456 9457 rx = kvzalloc(sz, GFP_KERNEL_ACCOUNT | __GFP_RETRY_MAYFAIL); 9458 if (!rx) 9459 return -ENOMEM; 9460 9461 dev->_rx = rx; 9462 9463 for (i = 0; i < count; i++) { 9464 rx[i].dev = dev; 9465 9466 /* XDP RX-queue setup */ 9467 err = xdp_rxq_info_reg(&rx[i].xdp_rxq, dev, i, 0); 9468 if (err < 0) 9469 goto err_rxq_info; 9470 } 9471 return 0; 9472 9473 err_rxq_info: 9474 /* Rollback successful reg's and free other resources */ 9475 while (i--) 9476 xdp_rxq_info_unreg(&rx[i].xdp_rxq); 9477 kvfree(dev->_rx); 9478 dev->_rx = NULL; 9479 return err; 9480 } 9481 9482 static void netif_free_rx_queues(struct net_device *dev) 9483 { 9484 unsigned int i, count = dev->num_rx_queues; 9485 9486 /* netif_alloc_rx_queues alloc failed, resources have been unreg'ed */ 9487 if (!dev->_rx) 9488 return; 9489 9490 for (i = 0; i < count; i++) 9491 xdp_rxq_info_unreg(&dev->_rx[i].xdp_rxq); 9492 9493 kvfree(dev->_rx); 9494 } 9495 9496 static void netdev_init_one_queue(struct net_device *dev, 9497 struct netdev_queue *queue, void *_unused) 9498 { 9499 /* Initialize queue lock */ 9500 spin_lock_init(&queue->_xmit_lock); 9501 netdev_set_xmit_lockdep_class(&queue->_xmit_lock, dev->type); 9502 queue->xmit_lock_owner = -1; 9503 netdev_queue_numa_node_write(queue, NUMA_NO_NODE); 9504 queue->dev = dev; 9505 #ifdef CONFIG_BQL 9506 dql_init(&queue->dql, HZ); 9507 #endif 9508 } 9509 9510 static void netif_free_tx_queues(struct net_device *dev) 9511 { 9512 kvfree(dev->_tx); 9513 } 9514 9515 static int netif_alloc_netdev_queues(struct net_device *dev) 9516 { 9517 unsigned int count = dev->num_tx_queues; 9518 struct netdev_queue *tx; 9519 size_t sz = count * sizeof(*tx); 9520 9521 if (count < 1 || count > 0xffff) 9522 return -EINVAL; 9523 9524 tx = kvzalloc(sz, GFP_KERNEL_ACCOUNT | __GFP_RETRY_MAYFAIL); 9525 if (!tx) 9526 return -ENOMEM; 9527 9528 dev->_tx = tx; 9529 9530 netdev_for_each_tx_queue(dev, netdev_init_one_queue, NULL); 9531 spin_lock_init(&dev->tx_global_lock); 9532 9533 return 0; 9534 } 9535 9536 void netif_tx_stop_all_queues(struct net_device *dev) 9537 { 9538 unsigned int i; 9539 9540 for (i = 0; i < dev->num_tx_queues; i++) { 9541 struct netdev_queue *txq = netdev_get_tx_queue(dev, i); 9542 9543 netif_tx_stop_queue(txq); 9544 } 9545 } 9546 EXPORT_SYMBOL(netif_tx_stop_all_queues); 9547 9548 /** 9549 * register_netdevice - register a network device 9550 * @dev: device to register 9551 * 9552 * Take a completed network device structure and add it to the kernel 9553 * interfaces. A %NETDEV_REGISTER message is sent to the netdev notifier 9554 * chain. 0 is returned on success. A negative errno code is returned 9555 * on a failure to set up the device, or if the name is a duplicate. 9556 * 9557 * Callers must hold the rtnl semaphore. You may want 9558 * register_netdev() instead of this. 9559 * 9560 * BUGS: 9561 * The locking appears insufficient to guarantee two parallel registers 9562 * will not get the same name. 9563 */ 9564 9565 int register_netdevice(struct net_device *dev) 9566 { 9567 int ret; 9568 struct net *net = dev_net(dev); 9569 9570 BUILD_BUG_ON(sizeof(netdev_features_t) * BITS_PER_BYTE < 9571 NETDEV_FEATURE_COUNT); 9572 BUG_ON(dev_boot_phase); 9573 ASSERT_RTNL(); 9574 9575 might_sleep(); 9576 9577 /* When net_device's are persistent, this will be fatal. */ 9578 BUG_ON(dev->reg_state != NETREG_UNINITIALIZED); 9579 BUG_ON(!net); 9580 9581 ret = ethtool_check_ops(dev->ethtool_ops); 9582 if (ret) 9583 return ret; 9584 9585 spin_lock_init(&dev->addr_list_lock); 9586 netdev_set_addr_lockdep_class(dev); 9587 9588 ret = dev_get_valid_name(net, dev, dev->name); 9589 if (ret < 0) 9590 goto out; 9591 9592 ret = -ENOMEM; 9593 dev->name_node = netdev_name_node_head_alloc(dev); 9594 if (!dev->name_node) 9595 goto out; 9596 9597 /* Init, if this function is available */ 9598 if (dev->netdev_ops->ndo_init) { 9599 ret = dev->netdev_ops->ndo_init(dev); 9600 if (ret) { 9601 if (ret > 0) 9602 ret = -EIO; 9603 goto err_free_name; 9604 } 9605 } 9606 9607 if (((dev->hw_features | dev->features) & 9608 NETIF_F_HW_VLAN_CTAG_FILTER) && 9609 (!dev->netdev_ops->ndo_vlan_rx_add_vid || 9610 !dev->netdev_ops->ndo_vlan_rx_kill_vid)) { 9611 netdev_WARN(dev, "Buggy VLAN acceleration in driver!\n"); 9612 ret = -EINVAL; 9613 goto err_uninit; 9614 } 9615 9616 ret = -EBUSY; 9617 if (!dev->ifindex) 9618 dev->ifindex = dev_new_index(net); 9619 else if (__dev_get_by_index(net, dev->ifindex)) 9620 goto err_uninit; 9621 9622 /* Transfer changeable features to wanted_features and enable 9623 * software offloads (GSO and GRO). 9624 */ 9625 dev->hw_features |= (NETIF_F_SOFT_FEATURES | NETIF_F_SOFT_FEATURES_OFF); 9626 dev->features |= NETIF_F_SOFT_FEATURES; 9627 9628 if (dev->udp_tunnel_nic_info) { 9629 dev->features |= NETIF_F_RX_UDP_TUNNEL_PORT; 9630 dev->hw_features |= NETIF_F_RX_UDP_TUNNEL_PORT; 9631 } 9632 9633 dev->wanted_features = dev->features & dev->hw_features; 9634 9635 if (!(dev->flags & IFF_LOOPBACK)) 9636 dev->hw_features |= NETIF_F_NOCACHE_COPY; 9637 9638 /* If IPv4 TCP segmentation offload is supported we should also 9639 * allow the device to enable segmenting the frame with the option 9640 * of ignoring a static IP ID value. This doesn't enable the 9641 * feature itself but allows the user to enable it later. 9642 */ 9643 if (dev->hw_features & NETIF_F_TSO) 9644 dev->hw_features |= NETIF_F_TSO_MANGLEID; 9645 if (dev->vlan_features & NETIF_F_TSO) 9646 dev->vlan_features |= NETIF_F_TSO_MANGLEID; 9647 if (dev->mpls_features & NETIF_F_TSO) 9648 dev->mpls_features |= NETIF_F_TSO_MANGLEID; 9649 if (dev->hw_enc_features & NETIF_F_TSO) 9650 dev->hw_enc_features |= NETIF_F_TSO_MANGLEID; 9651 9652 /* Make NETIF_F_HIGHDMA inheritable to VLAN devices. 9653 */ 9654 dev->vlan_features |= NETIF_F_HIGHDMA; 9655 9656 /* Make NETIF_F_SG inheritable to tunnel devices. 9657 */ 9658 dev->hw_enc_features |= NETIF_F_SG | NETIF_F_GSO_PARTIAL; 9659 9660 /* Make NETIF_F_SG inheritable to MPLS. 9661 */ 9662 dev->mpls_features |= NETIF_F_SG; 9663 9664 ret = call_netdevice_notifiers(NETDEV_POST_INIT, dev); 9665 ret = notifier_to_errno(ret); 9666 if (ret) 9667 goto err_uninit; 9668 9669 ret = netdev_register_kobject(dev); 9670 if (ret) { 9671 dev->reg_state = NETREG_UNREGISTERED; 9672 goto err_uninit; 9673 } 9674 dev->reg_state = NETREG_REGISTERED; 9675 9676 __netdev_update_features(dev); 9677 9678 /* 9679 * Default initial state at registry is that the 9680 * device is present. 9681 */ 9682 9683 set_bit(__LINK_STATE_PRESENT, &dev->state); 9684 9685 linkwatch_init_dev(dev); 9686 9687 dev_init_scheduler(dev); 9688 dev_hold(dev); 9689 list_netdevice(dev); 9690 add_device_randomness(dev->dev_addr, dev->addr_len); 9691 9692 /* If the device has permanent device address, driver should 9693 * set dev_addr and also addr_assign_type should be set to 9694 * NET_ADDR_PERM (default value). 9695 */ 9696 if (dev->addr_assign_type == NET_ADDR_PERM) 9697 memcpy(dev->perm_addr, dev->dev_addr, dev->addr_len); 9698 9699 /* Notify protocols, that a new device appeared. */ 9700 ret = call_netdevice_notifiers(NETDEV_REGISTER, dev); 9701 ret = notifier_to_errno(ret); 9702 if (ret) { 9703 /* Expect explicit free_netdev() on failure */ 9704 dev->needs_free_netdev = false; 9705 unregister_netdevice_queue(dev, NULL); 9706 goto out; 9707 } 9708 /* 9709 * Prevent userspace races by waiting until the network 9710 * device is fully setup before sending notifications. 9711 */ 9712 if (!dev->rtnl_link_ops || 9713 dev->rtnl_link_state == RTNL_LINK_INITIALIZED) 9714 rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U, GFP_KERNEL); 9715 9716 out: 9717 return ret; 9718 9719 err_uninit: 9720 if (dev->netdev_ops->ndo_uninit) 9721 dev->netdev_ops->ndo_uninit(dev); 9722 if (dev->priv_destructor) 9723 dev->priv_destructor(dev); 9724 err_free_name: 9725 netdev_name_node_free(dev->name_node); 9726 goto out; 9727 } 9728 EXPORT_SYMBOL(register_netdevice); 9729 9730 /** 9731 * init_dummy_netdev - init a dummy network device for NAPI 9732 * @dev: device to init 9733 * 9734 * This takes a network device structure and initialize the minimum 9735 * amount of fields so it can be used to schedule NAPI polls without 9736 * registering a full blown interface. This is to be used by drivers 9737 * that need to tie several hardware interfaces to a single NAPI 9738 * poll scheduler due to HW limitations. 9739 */ 9740 int init_dummy_netdev(struct net_device *dev) 9741 { 9742 /* Clear everything. Note we don't initialize spinlocks 9743 * are they aren't supposed to be taken by any of the 9744 * NAPI code and this dummy netdev is supposed to be 9745 * only ever used for NAPI polls 9746 */ 9747 memset(dev, 0, sizeof(struct net_device)); 9748 9749 /* make sure we BUG if trying to hit standard 9750 * register/unregister code path 9751 */ 9752 dev->reg_state = NETREG_DUMMY; 9753 9754 /* NAPI wants this */ 9755 INIT_LIST_HEAD(&dev->napi_list); 9756 9757 /* a dummy interface is started by default */ 9758 set_bit(__LINK_STATE_PRESENT, &dev->state); 9759 set_bit(__LINK_STATE_START, &dev->state); 9760 9761 /* napi_busy_loop stats accounting wants this */ 9762 dev_net_set(dev, &init_net); 9763 9764 /* Note : We dont allocate pcpu_refcnt for dummy devices, 9765 * because users of this 'device' dont need to change 9766 * its refcount. 9767 */ 9768 9769 return 0; 9770 } 9771 EXPORT_SYMBOL_GPL(init_dummy_netdev); 9772 9773 9774 /** 9775 * register_netdev - register a network device 9776 * @dev: device to register 9777 * 9778 * Take a completed network device structure and add it to the kernel 9779 * interfaces. A %NETDEV_REGISTER message is sent to the netdev notifier 9780 * chain. 0 is returned on success. A negative errno code is returned 9781 * on a failure to set up the device, or if the name is a duplicate. 9782 * 9783 * This is a wrapper around register_netdevice that takes the rtnl semaphore 9784 * and expands the device name if you passed a format string to 9785 * alloc_netdev. 9786 */ 9787 int register_netdev(struct net_device *dev) 9788 { 9789 int err; 9790 9791 if (rtnl_lock_killable()) 9792 return -EINTR; 9793 err = register_netdevice(dev); 9794 rtnl_unlock(); 9795 return err; 9796 } 9797 EXPORT_SYMBOL(register_netdev); 9798 9799 int netdev_refcnt_read(const struct net_device *dev) 9800 { 9801 #ifdef CONFIG_PCPU_DEV_REFCNT 9802 int i, refcnt = 0; 9803 9804 for_each_possible_cpu(i) 9805 refcnt += *per_cpu_ptr(dev->pcpu_refcnt, i); 9806 return refcnt; 9807 #else 9808 return refcount_read(&dev->dev_refcnt); 9809 #endif 9810 } 9811 EXPORT_SYMBOL(netdev_refcnt_read); 9812 9813 int netdev_unregister_timeout_secs __read_mostly = 10; 9814 9815 #define WAIT_REFS_MIN_MSECS 1 9816 #define WAIT_REFS_MAX_MSECS 250 9817 /** 9818 * netdev_wait_allrefs - wait until all references are gone. 9819 * @dev: target net_device 9820 * 9821 * This is called when unregistering network devices. 9822 * 9823 * Any protocol or device that holds a reference should register 9824 * for netdevice notification, and cleanup and put back the 9825 * reference if they receive an UNREGISTER event. 9826 * We can get stuck here if buggy protocols don't correctly 9827 * call dev_put. 9828 */ 9829 static void netdev_wait_allrefs(struct net_device *dev) 9830 { 9831 unsigned long rebroadcast_time, warning_time; 9832 int wait = 0, refcnt; 9833 9834 linkwatch_forget_dev(dev); 9835 9836 rebroadcast_time = warning_time = jiffies; 9837 refcnt = netdev_refcnt_read(dev); 9838 9839 while (refcnt != 1) { 9840 if (time_after(jiffies, rebroadcast_time + 1 * HZ)) { 9841 rtnl_lock(); 9842 9843 /* Rebroadcast unregister notification */ 9844 call_netdevice_notifiers(NETDEV_UNREGISTER, dev); 9845 9846 __rtnl_unlock(); 9847 rcu_barrier(); 9848 rtnl_lock(); 9849 9850 if (test_bit(__LINK_STATE_LINKWATCH_PENDING, 9851 &dev->state)) { 9852 /* We must not have linkwatch events 9853 * pending on unregister. If this 9854 * happens, we simply run the queue 9855 * unscheduled, resulting in a noop 9856 * for this device. 9857 */ 9858 linkwatch_run_queue(); 9859 } 9860 9861 __rtnl_unlock(); 9862 9863 rebroadcast_time = jiffies; 9864 } 9865 9866 if (!wait) { 9867 rcu_barrier(); 9868 wait = WAIT_REFS_MIN_MSECS; 9869 } else { 9870 msleep(wait); 9871 wait = min(wait << 1, WAIT_REFS_MAX_MSECS); 9872 } 9873 9874 refcnt = netdev_refcnt_read(dev); 9875 9876 if (refcnt != 1 && 9877 time_after(jiffies, warning_time + 9878 netdev_unregister_timeout_secs * HZ)) { 9879 pr_emerg("unregister_netdevice: waiting for %s to become free. Usage count = %d\n", 9880 dev->name, refcnt); 9881 warning_time = jiffies; 9882 } 9883 } 9884 } 9885 9886 /* The sequence is: 9887 * 9888 * rtnl_lock(); 9889 * ... 9890 * register_netdevice(x1); 9891 * register_netdevice(x2); 9892 * ... 9893 * unregister_netdevice(y1); 9894 * unregister_netdevice(y2); 9895 * ... 9896 * rtnl_unlock(); 9897 * free_netdev(y1); 9898 * free_netdev(y2); 9899 * 9900 * We are invoked by rtnl_unlock(). 9901 * This allows us to deal with problems: 9902 * 1) We can delete sysfs objects which invoke hotplug 9903 * without deadlocking with linkwatch via keventd. 9904 * 2) Since we run with the RTNL semaphore not held, we can sleep 9905 * safely in order to wait for the netdev refcnt to drop to zero. 9906 * 9907 * We must not return until all unregister events added during 9908 * the interval the lock was held have been completed. 9909 */ 9910 void netdev_run_todo(void) 9911 { 9912 struct list_head list; 9913 #ifdef CONFIG_LOCKDEP 9914 struct list_head unlink_list; 9915 9916 list_replace_init(&net_unlink_list, &unlink_list); 9917 9918 while (!list_empty(&unlink_list)) { 9919 struct net_device *dev = list_first_entry(&unlink_list, 9920 struct net_device, 9921 unlink_list); 9922 list_del_init(&dev->unlink_list); 9923 dev->nested_level = dev->lower_level - 1; 9924 } 9925 #endif 9926 9927 /* Snapshot list, allow later requests */ 9928 list_replace_init(&net_todo_list, &list); 9929 9930 __rtnl_unlock(); 9931 9932 9933 /* Wait for rcu callbacks to finish before next phase */ 9934 if (!list_empty(&list)) 9935 rcu_barrier(); 9936 9937 while (!list_empty(&list)) { 9938 struct net_device *dev 9939 = list_first_entry(&list, struct net_device, todo_list); 9940 list_del(&dev->todo_list); 9941 9942 if (unlikely(dev->reg_state != NETREG_UNREGISTERING)) { 9943 pr_err("network todo '%s' but state %d\n", 9944 dev->name, dev->reg_state); 9945 dump_stack(); 9946 continue; 9947 } 9948 9949 dev->reg_state = NETREG_UNREGISTERED; 9950 9951 netdev_wait_allrefs(dev); 9952 9953 /* paranoia */ 9954 BUG_ON(netdev_refcnt_read(dev) != 1); 9955 BUG_ON(!list_empty(&dev->ptype_all)); 9956 BUG_ON(!list_empty(&dev->ptype_specific)); 9957 WARN_ON(rcu_access_pointer(dev->ip_ptr)); 9958 WARN_ON(rcu_access_pointer(dev->ip6_ptr)); 9959 #if IS_ENABLED(CONFIG_DECNET) 9960 WARN_ON(dev->dn_ptr); 9961 #endif 9962 if (dev->priv_destructor) 9963 dev->priv_destructor(dev); 9964 if (dev->needs_free_netdev) 9965 free_netdev(dev); 9966 9967 /* Report a network device has been unregistered */ 9968 rtnl_lock(); 9969 dev_net(dev)->dev_unreg_count--; 9970 __rtnl_unlock(); 9971 wake_up(&netdev_unregistering_wq); 9972 9973 /* Free network device */ 9974 kobject_put(&dev->dev.kobj); 9975 } 9976 } 9977 9978 /* Convert net_device_stats to rtnl_link_stats64. rtnl_link_stats64 has 9979 * all the same fields in the same order as net_device_stats, with only 9980 * the type differing, but rtnl_link_stats64 may have additional fields 9981 * at the end for newer counters. 9982 */ 9983 void netdev_stats_to_stats64(struct rtnl_link_stats64 *stats64, 9984 const struct net_device_stats *netdev_stats) 9985 { 9986 #if BITS_PER_LONG == 64 9987 BUILD_BUG_ON(sizeof(*stats64) < sizeof(*netdev_stats)); 9988 memcpy(stats64, netdev_stats, sizeof(*netdev_stats)); 9989 /* zero out counters that only exist in rtnl_link_stats64 */ 9990 memset((char *)stats64 + sizeof(*netdev_stats), 0, 9991 sizeof(*stats64) - sizeof(*netdev_stats)); 9992 #else 9993 size_t i, n = sizeof(*netdev_stats) / sizeof(unsigned long); 9994 const unsigned long *src = (const unsigned long *)netdev_stats; 9995 u64 *dst = (u64 *)stats64; 9996 9997 BUILD_BUG_ON(n > sizeof(*stats64) / sizeof(u64)); 9998 for (i = 0; i < n; i++) 9999 dst[i] = src[i]; 10000 /* zero out counters that only exist in rtnl_link_stats64 */ 10001 memset((char *)stats64 + n * sizeof(u64), 0, 10002 sizeof(*stats64) - n * sizeof(u64)); 10003 #endif 10004 } 10005 EXPORT_SYMBOL(netdev_stats_to_stats64); 10006 10007 /** 10008 * dev_get_stats - get network device statistics 10009 * @dev: device to get statistics from 10010 * @storage: place to store stats 10011 * 10012 * Get network statistics from device. Return @storage. 10013 * The device driver may provide its own method by setting 10014 * dev->netdev_ops->get_stats64 or dev->netdev_ops->get_stats; 10015 * otherwise the internal statistics structure is used. 10016 */ 10017 struct rtnl_link_stats64 *dev_get_stats(struct net_device *dev, 10018 struct rtnl_link_stats64 *storage) 10019 { 10020 const struct net_device_ops *ops = dev->netdev_ops; 10021 10022 if (ops->ndo_get_stats64) { 10023 memset(storage, 0, sizeof(*storage)); 10024 ops->ndo_get_stats64(dev, storage); 10025 } else if (ops->ndo_get_stats) { 10026 netdev_stats_to_stats64(storage, ops->ndo_get_stats(dev)); 10027 } else { 10028 netdev_stats_to_stats64(storage, &dev->stats); 10029 } 10030 storage->rx_dropped += (unsigned long)atomic_long_read(&dev->rx_dropped); 10031 storage->tx_dropped += (unsigned long)atomic_long_read(&dev->tx_dropped); 10032 storage->rx_nohandler += (unsigned long)atomic_long_read(&dev->rx_nohandler); 10033 return storage; 10034 } 10035 EXPORT_SYMBOL(dev_get_stats); 10036 10037 /** 10038 * dev_fetch_sw_netstats - get per-cpu network device statistics 10039 * @s: place to store stats 10040 * @netstats: per-cpu network stats to read from 10041 * 10042 * Read per-cpu network statistics and populate the related fields in @s. 10043 */ 10044 void dev_fetch_sw_netstats(struct rtnl_link_stats64 *s, 10045 const struct pcpu_sw_netstats __percpu *netstats) 10046 { 10047 int cpu; 10048 10049 for_each_possible_cpu(cpu) { 10050 const struct pcpu_sw_netstats *stats; 10051 struct pcpu_sw_netstats tmp; 10052 unsigned int start; 10053 10054 stats = per_cpu_ptr(netstats, cpu); 10055 do { 10056 start = u64_stats_fetch_begin_irq(&stats->syncp); 10057 tmp.rx_packets = stats->rx_packets; 10058 tmp.rx_bytes = stats->rx_bytes; 10059 tmp.tx_packets = stats->tx_packets; 10060 tmp.tx_bytes = stats->tx_bytes; 10061 } while (u64_stats_fetch_retry_irq(&stats->syncp, start)); 10062 10063 s->rx_packets += tmp.rx_packets; 10064 s->rx_bytes += tmp.rx_bytes; 10065 s->tx_packets += tmp.tx_packets; 10066 s->tx_bytes += tmp.tx_bytes; 10067 } 10068 } 10069 EXPORT_SYMBOL_GPL(dev_fetch_sw_netstats); 10070 10071 /** 10072 * dev_get_tstats64 - ndo_get_stats64 implementation 10073 * @dev: device to get statistics from 10074 * @s: place to store stats 10075 * 10076 * Populate @s from dev->stats and dev->tstats. Can be used as 10077 * ndo_get_stats64() callback. 10078 */ 10079 void dev_get_tstats64(struct net_device *dev, struct rtnl_link_stats64 *s) 10080 { 10081 netdev_stats_to_stats64(s, &dev->stats); 10082 dev_fetch_sw_netstats(s, dev->tstats); 10083 } 10084 EXPORT_SYMBOL_GPL(dev_get_tstats64); 10085 10086 struct netdev_queue *dev_ingress_queue_create(struct net_device *dev) 10087 { 10088 struct netdev_queue *queue = dev_ingress_queue(dev); 10089 10090 #ifdef CONFIG_NET_CLS_ACT 10091 if (queue) 10092 return queue; 10093 queue = kzalloc(sizeof(*queue), GFP_KERNEL); 10094 if (!queue) 10095 return NULL; 10096 netdev_init_one_queue(dev, queue, NULL); 10097 RCU_INIT_POINTER(queue->qdisc, &noop_qdisc); 10098 queue->qdisc_sleeping = &noop_qdisc; 10099 rcu_assign_pointer(dev->ingress_queue, queue); 10100 #endif 10101 return queue; 10102 } 10103 10104 static const struct ethtool_ops default_ethtool_ops; 10105 10106 void netdev_set_default_ethtool_ops(struct net_device *dev, 10107 const struct ethtool_ops *ops) 10108 { 10109 if (dev->ethtool_ops == &default_ethtool_ops) 10110 dev->ethtool_ops = ops; 10111 } 10112 EXPORT_SYMBOL_GPL(netdev_set_default_ethtool_ops); 10113 10114 void netdev_freemem(struct net_device *dev) 10115 { 10116 char *addr = (char *)dev - dev->padded; 10117 10118 kvfree(addr); 10119 } 10120 10121 /** 10122 * alloc_netdev_mqs - allocate network device 10123 * @sizeof_priv: size of private data to allocate space for 10124 * @name: device name format string 10125 * @name_assign_type: origin of device name 10126 * @setup: callback to initialize device 10127 * @txqs: the number of TX subqueues to allocate 10128 * @rxqs: the number of RX subqueues to allocate 10129 * 10130 * Allocates a struct net_device with private data area for driver use 10131 * and performs basic initialization. Also allocates subqueue structs 10132 * for each queue on the device. 10133 */ 10134 struct net_device *alloc_netdev_mqs(int sizeof_priv, const char *name, 10135 unsigned char name_assign_type, 10136 void (*setup)(struct net_device *), 10137 unsigned int txqs, unsigned int rxqs) 10138 { 10139 struct net_device *dev; 10140 unsigned int alloc_size; 10141 struct net_device *p; 10142 10143 BUG_ON(strlen(name) >= sizeof(dev->name)); 10144 10145 if (txqs < 1) { 10146 pr_err("alloc_netdev: Unable to allocate device with zero queues\n"); 10147 return NULL; 10148 } 10149 10150 if (rxqs < 1) { 10151 pr_err("alloc_netdev: Unable to allocate device with zero RX queues\n"); 10152 return NULL; 10153 } 10154 10155 alloc_size = sizeof(struct net_device); 10156 if (sizeof_priv) { 10157 /* ensure 32-byte alignment of private area */ 10158 alloc_size = ALIGN(alloc_size, NETDEV_ALIGN); 10159 alloc_size += sizeof_priv; 10160 } 10161 /* ensure 32-byte alignment of whole construct */ 10162 alloc_size += NETDEV_ALIGN - 1; 10163 10164 p = kvzalloc(alloc_size, GFP_KERNEL_ACCOUNT | __GFP_RETRY_MAYFAIL); 10165 if (!p) 10166 return NULL; 10167 10168 dev = PTR_ALIGN(p, NETDEV_ALIGN); 10169 dev->padded = (char *)dev - (char *)p; 10170 10171 #ifdef CONFIG_PCPU_DEV_REFCNT 10172 dev->pcpu_refcnt = alloc_percpu(int); 10173 if (!dev->pcpu_refcnt) 10174 goto free_dev; 10175 dev_hold(dev); 10176 #else 10177 refcount_set(&dev->dev_refcnt, 1); 10178 #endif 10179 10180 if (dev_addr_init(dev)) 10181 goto free_pcpu; 10182 10183 dev_mc_init(dev); 10184 dev_uc_init(dev); 10185 10186 dev_net_set(dev, &init_net); 10187 10188 dev->gso_max_size = GSO_MAX_SIZE; 10189 dev->gso_max_segs = GSO_MAX_SEGS; 10190 dev->upper_level = 1; 10191 dev->lower_level = 1; 10192 #ifdef CONFIG_LOCKDEP 10193 dev->nested_level = 0; 10194 INIT_LIST_HEAD(&dev->unlink_list); 10195 #endif 10196 10197 INIT_LIST_HEAD(&dev->napi_list); 10198 INIT_LIST_HEAD(&dev->unreg_list); 10199 INIT_LIST_HEAD(&dev->close_list); 10200 INIT_LIST_HEAD(&dev->link_watch_list); 10201 INIT_LIST_HEAD(&dev->adj_list.upper); 10202 INIT_LIST_HEAD(&dev->adj_list.lower); 10203 INIT_LIST_HEAD(&dev->ptype_all); 10204 INIT_LIST_HEAD(&dev->ptype_specific); 10205 INIT_LIST_HEAD(&dev->net_notifier_list); 10206 #ifdef CONFIG_NET_SCHED 10207 hash_init(dev->qdisc_hash); 10208 #endif 10209 dev->priv_flags = IFF_XMIT_DST_RELEASE | IFF_XMIT_DST_RELEASE_PERM; 10210 setup(dev); 10211 10212 if (!dev->tx_queue_len) { 10213 dev->priv_flags |= IFF_NO_QUEUE; 10214 dev->tx_queue_len = DEFAULT_TX_QUEUE_LEN; 10215 } 10216 10217 dev->num_tx_queues = txqs; 10218 dev->real_num_tx_queues = txqs; 10219 if (netif_alloc_netdev_queues(dev)) 10220 goto free_all; 10221 10222 dev->num_rx_queues = rxqs; 10223 dev->real_num_rx_queues = rxqs; 10224 if (netif_alloc_rx_queues(dev)) 10225 goto free_all; 10226 10227 strcpy(dev->name, name); 10228 dev->name_assign_type = name_assign_type; 10229 dev->group = INIT_NETDEV_GROUP; 10230 if (!dev->ethtool_ops) 10231 dev->ethtool_ops = &default_ethtool_ops; 10232 10233 nf_hook_netdev_init(dev); 10234 10235 return dev; 10236 10237 free_all: 10238 free_netdev(dev); 10239 return NULL; 10240 10241 free_pcpu: 10242 #ifdef CONFIG_PCPU_DEV_REFCNT 10243 free_percpu(dev->pcpu_refcnt); 10244 free_dev: 10245 #endif 10246 netdev_freemem(dev); 10247 return NULL; 10248 } 10249 EXPORT_SYMBOL(alloc_netdev_mqs); 10250 10251 /** 10252 * free_netdev - free network device 10253 * @dev: device 10254 * 10255 * This function does the last stage of destroying an allocated device 10256 * interface. The reference to the device object is released. If this 10257 * is the last reference then it will be freed.Must be called in process 10258 * context. 10259 */ 10260 void free_netdev(struct net_device *dev) 10261 { 10262 struct napi_struct *p, *n; 10263 10264 might_sleep(); 10265 10266 /* When called immediately after register_netdevice() failed the unwind 10267 * handling may still be dismantling the device. Handle that case by 10268 * deferring the free. 10269 */ 10270 if (dev->reg_state == NETREG_UNREGISTERING) { 10271 ASSERT_RTNL(); 10272 dev->needs_free_netdev = true; 10273 return; 10274 } 10275 10276 netif_free_tx_queues(dev); 10277 netif_free_rx_queues(dev); 10278 10279 kfree(rcu_dereference_protected(dev->ingress_queue, 1)); 10280 10281 /* Flush device addresses */ 10282 dev_addr_flush(dev); 10283 10284 list_for_each_entry_safe(p, n, &dev->napi_list, dev_list) 10285 netif_napi_del(p); 10286 10287 #ifdef CONFIG_PCPU_DEV_REFCNT 10288 free_percpu(dev->pcpu_refcnt); 10289 dev->pcpu_refcnt = NULL; 10290 #endif 10291 free_percpu(dev->xdp_bulkq); 10292 dev->xdp_bulkq = NULL; 10293 10294 /* Compatibility with error handling in drivers */ 10295 if (dev->reg_state == NETREG_UNINITIALIZED) { 10296 netdev_freemem(dev); 10297 return; 10298 } 10299 10300 BUG_ON(dev->reg_state != NETREG_UNREGISTERED); 10301 dev->reg_state = NETREG_RELEASED; 10302 10303 /* will free via device release */ 10304 put_device(&dev->dev); 10305 } 10306 EXPORT_SYMBOL(free_netdev); 10307 10308 /** 10309 * synchronize_net - Synchronize with packet receive processing 10310 * 10311 * Wait for packets currently being received to be done. 10312 * Does not block later packets from starting. 10313 */ 10314 void synchronize_net(void) 10315 { 10316 might_sleep(); 10317 if (rtnl_is_locked()) 10318 synchronize_rcu_expedited(); 10319 else 10320 synchronize_rcu(); 10321 } 10322 EXPORT_SYMBOL(synchronize_net); 10323 10324 /** 10325 * unregister_netdevice_queue - remove device from the kernel 10326 * @dev: device 10327 * @head: list 10328 * 10329 * This function shuts down a device interface and removes it 10330 * from the kernel tables. 10331 * If head not NULL, device is queued to be unregistered later. 10332 * 10333 * Callers must hold the rtnl semaphore. You may want 10334 * unregister_netdev() instead of this. 10335 */ 10336 10337 void unregister_netdevice_queue(struct net_device *dev, struct list_head *head) 10338 { 10339 ASSERT_RTNL(); 10340 10341 if (head) { 10342 list_move_tail(&dev->unreg_list, head); 10343 } else { 10344 LIST_HEAD(single); 10345 10346 list_add(&dev->unreg_list, &single); 10347 unregister_netdevice_many(&single); 10348 } 10349 } 10350 EXPORT_SYMBOL(unregister_netdevice_queue); 10351 10352 /** 10353 * unregister_netdevice_many - unregister many devices 10354 * @head: list of devices 10355 * 10356 * Note: As most callers use a stack allocated list_head, 10357 * we force a list_del() to make sure stack wont be corrupted later. 10358 */ 10359 void unregister_netdevice_many(struct list_head *head) 10360 { 10361 struct net_device *dev, *tmp; 10362 LIST_HEAD(close_head); 10363 10364 BUG_ON(dev_boot_phase); 10365 ASSERT_RTNL(); 10366 10367 if (list_empty(head)) 10368 return; 10369 10370 list_for_each_entry_safe(dev, tmp, head, unreg_list) { 10371 /* Some devices call without registering 10372 * for initialization unwind. Remove those 10373 * devices and proceed with the remaining. 10374 */ 10375 if (dev->reg_state == NETREG_UNINITIALIZED) { 10376 pr_debug("unregister_netdevice: device %s/%p never was registered\n", 10377 dev->name, dev); 10378 10379 WARN_ON(1); 10380 list_del(&dev->unreg_list); 10381 continue; 10382 } 10383 dev->dismantle = true; 10384 BUG_ON(dev->reg_state != NETREG_REGISTERED); 10385 } 10386 10387 /* If device is running, close it first. */ 10388 list_for_each_entry(dev, head, unreg_list) 10389 list_add_tail(&dev->close_list, &close_head); 10390 dev_close_many(&close_head, true); 10391 10392 list_for_each_entry(dev, head, unreg_list) { 10393 /* And unlink it from device chain. */ 10394 unlist_netdevice(dev); 10395 10396 dev->reg_state = NETREG_UNREGISTERING; 10397 } 10398 flush_all_backlogs(); 10399 10400 synchronize_net(); 10401 10402 list_for_each_entry(dev, head, unreg_list) { 10403 struct sk_buff *skb = NULL; 10404 10405 /* Shutdown queueing discipline. */ 10406 dev_shutdown(dev); 10407 10408 dev_xdp_uninstall(dev); 10409 10410 /* Notify protocols, that we are about to destroy 10411 * this device. They should clean all the things. 10412 */ 10413 call_netdevice_notifiers(NETDEV_UNREGISTER, dev); 10414 10415 if (!dev->rtnl_link_ops || 10416 dev->rtnl_link_state == RTNL_LINK_INITIALIZED) 10417 skb = rtmsg_ifinfo_build_skb(RTM_DELLINK, dev, ~0U, 0, 10418 GFP_KERNEL, NULL, 0); 10419 10420 /* 10421 * Flush the unicast and multicast chains 10422 */ 10423 dev_uc_flush(dev); 10424 dev_mc_flush(dev); 10425 10426 netdev_name_node_alt_flush(dev); 10427 netdev_name_node_free(dev->name_node); 10428 10429 if (dev->netdev_ops->ndo_uninit) 10430 dev->netdev_ops->ndo_uninit(dev); 10431 10432 if (skb) 10433 rtmsg_ifinfo_send(skb, dev, GFP_KERNEL); 10434 10435 /* Notifier chain MUST detach us all upper devices. */ 10436 WARN_ON(netdev_has_any_upper_dev(dev)); 10437 WARN_ON(netdev_has_any_lower_dev(dev)); 10438 10439 /* Remove entries from kobject tree */ 10440 netdev_unregister_kobject(dev); 10441 #ifdef CONFIG_XPS 10442 /* Remove XPS queueing entries */ 10443 netif_reset_xps_queues_gt(dev, 0); 10444 #endif 10445 } 10446 10447 synchronize_net(); 10448 10449 list_for_each_entry(dev, head, unreg_list) { 10450 dev_put(dev); 10451 net_set_todo(dev); 10452 } 10453 10454 list_del(head); 10455 } 10456 EXPORT_SYMBOL(unregister_netdevice_many); 10457 10458 /** 10459 * unregister_netdev - remove device from the kernel 10460 * @dev: device 10461 * 10462 * This function shuts down a device interface and removes it 10463 * from the kernel tables. 10464 * 10465 * This is just a wrapper for unregister_netdevice that takes 10466 * the rtnl semaphore. In general you want to use this and not 10467 * unregister_netdevice. 10468 */ 10469 void unregister_netdev(struct net_device *dev) 10470 { 10471 rtnl_lock(); 10472 unregister_netdevice(dev); 10473 rtnl_unlock(); 10474 } 10475 EXPORT_SYMBOL(unregister_netdev); 10476 10477 /** 10478 * __dev_change_net_namespace - move device to different nethost namespace 10479 * @dev: device 10480 * @net: network namespace 10481 * @pat: If not NULL name pattern to try if the current device name 10482 * is already taken in the destination network namespace. 10483 * @new_ifindex: If not zero, specifies device index in the target 10484 * namespace. 10485 * 10486 * This function shuts down a device interface and moves it 10487 * to a new network namespace. On success 0 is returned, on 10488 * a failure a netagive errno code is returned. 10489 * 10490 * Callers must hold the rtnl semaphore. 10491 */ 10492 10493 int __dev_change_net_namespace(struct net_device *dev, struct net *net, 10494 const char *pat, int new_ifindex) 10495 { 10496 struct net *net_old = dev_net(dev); 10497 int err, new_nsid; 10498 10499 ASSERT_RTNL(); 10500 10501 /* Don't allow namespace local devices to be moved. */ 10502 err = -EINVAL; 10503 if (dev->features & NETIF_F_NETNS_LOCAL) 10504 goto out; 10505 10506 /* Ensure the device has been registrered */ 10507 if (dev->reg_state != NETREG_REGISTERED) 10508 goto out; 10509 10510 /* Get out if there is nothing todo */ 10511 err = 0; 10512 if (net_eq(net_old, net)) 10513 goto out; 10514 10515 /* Pick the destination device name, and ensure 10516 * we can use it in the destination network namespace. 10517 */ 10518 err = -EEXIST; 10519 if (netdev_name_in_use(net, dev->name)) { 10520 /* We get here if we can't use the current device name */ 10521 if (!pat) 10522 goto out; 10523 err = dev_get_valid_name(net, dev, pat); 10524 if (err < 0) 10525 goto out; 10526 } 10527 10528 /* Check that new_ifindex isn't used yet. */ 10529 err = -EBUSY; 10530 if (new_ifindex && __dev_get_by_index(net, new_ifindex)) 10531 goto out; 10532 10533 /* 10534 * And now a mini version of register_netdevice unregister_netdevice. 10535 */ 10536 10537 /* If device is running close it first. */ 10538 dev_close(dev); 10539 10540 /* And unlink it from device chain */ 10541 unlist_netdevice(dev); 10542 10543 synchronize_net(); 10544 10545 /* Shutdown queueing discipline. */ 10546 dev_shutdown(dev); 10547 10548 /* Notify protocols, that we are about to destroy 10549 * this device. They should clean all the things. 10550 * 10551 * Note that dev->reg_state stays at NETREG_REGISTERED. 10552 * This is wanted because this way 8021q and macvlan know 10553 * the device is just moving and can keep their slaves up. 10554 */ 10555 call_netdevice_notifiers(NETDEV_UNREGISTER, dev); 10556 rcu_barrier(); 10557 10558 new_nsid = peernet2id_alloc(dev_net(dev), net, GFP_KERNEL); 10559 /* If there is an ifindex conflict assign a new one */ 10560 if (!new_ifindex) { 10561 if (__dev_get_by_index(net, dev->ifindex)) 10562 new_ifindex = dev_new_index(net); 10563 else 10564 new_ifindex = dev->ifindex; 10565 } 10566 10567 rtmsg_ifinfo_newnet(RTM_DELLINK, dev, ~0U, GFP_KERNEL, &new_nsid, 10568 new_ifindex); 10569 10570 /* 10571 * Flush the unicast and multicast chains 10572 */ 10573 dev_uc_flush(dev); 10574 dev_mc_flush(dev); 10575 10576 /* Send a netdev-removed uevent to the old namespace */ 10577 kobject_uevent(&dev->dev.kobj, KOBJ_REMOVE); 10578 netdev_adjacent_del_links(dev); 10579 10580 /* Move per-net netdevice notifiers that are following the netdevice */ 10581 move_netdevice_notifiers_dev_net(dev, net); 10582 10583 /* Actually switch the network namespace */ 10584 dev_net_set(dev, net); 10585 dev->ifindex = new_ifindex; 10586 10587 /* Send a netdev-add uevent to the new namespace */ 10588 kobject_uevent(&dev->dev.kobj, KOBJ_ADD); 10589 netdev_adjacent_add_links(dev); 10590 10591 /* Fixup kobjects */ 10592 err = device_rename(&dev->dev, dev->name); 10593 WARN_ON(err); 10594 10595 /* Adapt owner in case owning user namespace of target network 10596 * namespace is different from the original one. 10597 */ 10598 err = netdev_change_owner(dev, net_old, net); 10599 WARN_ON(err); 10600 10601 /* Add the device back in the hashes */ 10602 list_netdevice(dev); 10603 10604 /* Notify protocols, that a new device appeared. */ 10605 call_netdevice_notifiers(NETDEV_REGISTER, dev); 10606 10607 /* 10608 * Prevent userspace races by waiting until the network 10609 * device is fully setup before sending notifications. 10610 */ 10611 rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U, GFP_KERNEL); 10612 10613 synchronize_net(); 10614 err = 0; 10615 out: 10616 return err; 10617 } 10618 EXPORT_SYMBOL_GPL(__dev_change_net_namespace); 10619 10620 static int dev_cpu_dead(unsigned int oldcpu) 10621 { 10622 struct sk_buff **list_skb; 10623 struct sk_buff *skb; 10624 unsigned int cpu; 10625 struct softnet_data *sd, *oldsd, *remsd = NULL; 10626 10627 local_irq_disable(); 10628 cpu = smp_processor_id(); 10629 sd = &per_cpu(softnet_data, cpu); 10630 oldsd = &per_cpu(softnet_data, oldcpu); 10631 10632 /* Find end of our completion_queue. */ 10633 list_skb = &sd->completion_queue; 10634 while (*list_skb) 10635 list_skb = &(*list_skb)->next; 10636 /* Append completion queue from offline CPU. */ 10637 *list_skb = oldsd->completion_queue; 10638 oldsd->completion_queue = NULL; 10639 10640 /* Append output queue from offline CPU. */ 10641 if (oldsd->output_queue) { 10642 *sd->output_queue_tailp = oldsd->output_queue; 10643 sd->output_queue_tailp = oldsd->output_queue_tailp; 10644 oldsd->output_queue = NULL; 10645 oldsd->output_queue_tailp = &oldsd->output_queue; 10646 } 10647 /* Append NAPI poll list from offline CPU, with one exception : 10648 * process_backlog() must be called by cpu owning percpu backlog. 10649 * We properly handle process_queue & input_pkt_queue later. 10650 */ 10651 while (!list_empty(&oldsd->poll_list)) { 10652 struct napi_struct *napi = list_first_entry(&oldsd->poll_list, 10653 struct napi_struct, 10654 poll_list); 10655 10656 list_del_init(&napi->poll_list); 10657 if (napi->poll == process_backlog) 10658 napi->state = 0; 10659 else 10660 ____napi_schedule(sd, napi); 10661 } 10662 10663 raise_softirq_irqoff(NET_TX_SOFTIRQ); 10664 local_irq_enable(); 10665 10666 #ifdef CONFIG_RPS 10667 remsd = oldsd->rps_ipi_list; 10668 oldsd->rps_ipi_list = NULL; 10669 #endif 10670 /* send out pending IPI's on offline CPU */ 10671 net_rps_send_ipi(remsd); 10672 10673 /* Process offline CPU's input_pkt_queue */ 10674 while ((skb = __skb_dequeue(&oldsd->process_queue))) { 10675 netif_rx_ni(skb); 10676 input_queue_head_incr(oldsd); 10677 } 10678 while ((skb = skb_dequeue(&oldsd->input_pkt_queue))) { 10679 netif_rx_ni(skb); 10680 input_queue_head_incr(oldsd); 10681 } 10682 10683 return 0; 10684 } 10685 10686 /** 10687 * netdev_increment_features - increment feature set by one 10688 * @all: current feature set 10689 * @one: new feature set 10690 * @mask: mask feature set 10691 * 10692 * Computes a new feature set after adding a device with feature set 10693 * @one to the master device with current feature set @all. Will not 10694 * enable anything that is off in @mask. Returns the new feature set. 10695 */ 10696 netdev_features_t netdev_increment_features(netdev_features_t all, 10697 netdev_features_t one, netdev_features_t mask) 10698 { 10699 if (mask & NETIF_F_HW_CSUM) 10700 mask |= NETIF_F_CSUM_MASK; 10701 mask |= NETIF_F_VLAN_CHALLENGED; 10702 10703 all |= one & (NETIF_F_ONE_FOR_ALL | NETIF_F_CSUM_MASK) & mask; 10704 all &= one | ~NETIF_F_ALL_FOR_ALL; 10705 10706 /* If one device supports hw checksumming, set for all. */ 10707 if (all & NETIF_F_HW_CSUM) 10708 all &= ~(NETIF_F_CSUM_MASK & ~NETIF_F_HW_CSUM); 10709 10710 return all; 10711 } 10712 EXPORT_SYMBOL(netdev_increment_features); 10713 10714 static struct hlist_head * __net_init netdev_create_hash(void) 10715 { 10716 int i; 10717 struct hlist_head *hash; 10718 10719 hash = kmalloc_array(NETDEV_HASHENTRIES, sizeof(*hash), GFP_KERNEL); 10720 if (hash != NULL) 10721 for (i = 0; i < NETDEV_HASHENTRIES; i++) 10722 INIT_HLIST_HEAD(&hash[i]); 10723 10724 return hash; 10725 } 10726 10727 /* Initialize per network namespace state */ 10728 static int __net_init netdev_init(struct net *net) 10729 { 10730 BUILD_BUG_ON(GRO_HASH_BUCKETS > 10731 8 * sizeof_field(struct napi_struct, gro_bitmask)); 10732 10733 if (net != &init_net) 10734 INIT_LIST_HEAD(&net->dev_base_head); 10735 10736 net->dev_name_head = netdev_create_hash(); 10737 if (net->dev_name_head == NULL) 10738 goto err_name; 10739 10740 net->dev_index_head = netdev_create_hash(); 10741 if (net->dev_index_head == NULL) 10742 goto err_idx; 10743 10744 RAW_INIT_NOTIFIER_HEAD(&net->netdev_chain); 10745 10746 return 0; 10747 10748 err_idx: 10749 kfree(net->dev_name_head); 10750 err_name: 10751 return -ENOMEM; 10752 } 10753 10754 /** 10755 * netdev_drivername - network driver for the device 10756 * @dev: network device 10757 * 10758 * Determine network driver for device. 10759 */ 10760 const char *netdev_drivername(const struct net_device *dev) 10761 { 10762 const struct device_driver *driver; 10763 const struct device *parent; 10764 const char *empty = ""; 10765 10766 parent = dev->dev.parent; 10767 if (!parent) 10768 return empty; 10769 10770 driver = parent->driver; 10771 if (driver && driver->name) 10772 return driver->name; 10773 return empty; 10774 } 10775 10776 static void __netdev_printk(const char *level, const struct net_device *dev, 10777 struct va_format *vaf) 10778 { 10779 if (dev && dev->dev.parent) { 10780 dev_printk_emit(level[1] - '0', 10781 dev->dev.parent, 10782 "%s %s %s%s: %pV", 10783 dev_driver_string(dev->dev.parent), 10784 dev_name(dev->dev.parent), 10785 netdev_name(dev), netdev_reg_state(dev), 10786 vaf); 10787 } else if (dev) { 10788 printk("%s%s%s: %pV", 10789 level, netdev_name(dev), netdev_reg_state(dev), vaf); 10790 } else { 10791 printk("%s(NULL net_device): %pV", level, vaf); 10792 } 10793 } 10794 10795 void netdev_printk(const char *level, const struct net_device *dev, 10796 const char *format, ...) 10797 { 10798 struct va_format vaf; 10799 va_list args; 10800 10801 va_start(args, format); 10802 10803 vaf.fmt = format; 10804 vaf.va = &args; 10805 10806 __netdev_printk(level, dev, &vaf); 10807 10808 va_end(args); 10809 } 10810 EXPORT_SYMBOL(netdev_printk); 10811 10812 #define define_netdev_printk_level(func, level) \ 10813 void func(const struct net_device *dev, const char *fmt, ...) \ 10814 { \ 10815 struct va_format vaf; \ 10816 va_list args; \ 10817 \ 10818 va_start(args, fmt); \ 10819 \ 10820 vaf.fmt = fmt; \ 10821 vaf.va = &args; \ 10822 \ 10823 __netdev_printk(level, dev, &vaf); \ 10824 \ 10825 va_end(args); \ 10826 } \ 10827 EXPORT_SYMBOL(func); 10828 10829 define_netdev_printk_level(netdev_emerg, KERN_EMERG); 10830 define_netdev_printk_level(netdev_alert, KERN_ALERT); 10831 define_netdev_printk_level(netdev_crit, KERN_CRIT); 10832 define_netdev_printk_level(netdev_err, KERN_ERR); 10833 define_netdev_printk_level(netdev_warn, KERN_WARNING); 10834 define_netdev_printk_level(netdev_notice, KERN_NOTICE); 10835 define_netdev_printk_level(netdev_info, KERN_INFO); 10836 10837 static void __net_exit netdev_exit(struct net *net) 10838 { 10839 kfree(net->dev_name_head); 10840 kfree(net->dev_index_head); 10841 if (net != &init_net) 10842 WARN_ON_ONCE(!list_empty(&net->dev_base_head)); 10843 } 10844 10845 static struct pernet_operations __net_initdata netdev_net_ops = { 10846 .init = netdev_init, 10847 .exit = netdev_exit, 10848 }; 10849 10850 static void __net_exit default_device_exit(struct net *net) 10851 { 10852 struct net_device *dev, *aux; 10853 /* 10854 * Push all migratable network devices back to the 10855 * initial network namespace 10856 */ 10857 rtnl_lock(); 10858 for_each_netdev_safe(net, dev, aux) { 10859 int err; 10860 char fb_name[IFNAMSIZ]; 10861 10862 /* Ignore unmoveable devices (i.e. loopback) */ 10863 if (dev->features & NETIF_F_NETNS_LOCAL) 10864 continue; 10865 10866 /* Leave virtual devices for the generic cleanup */ 10867 if (dev->rtnl_link_ops && !dev->rtnl_link_ops->netns_refund) 10868 continue; 10869 10870 /* Push remaining network devices to init_net */ 10871 snprintf(fb_name, IFNAMSIZ, "dev%d", dev->ifindex); 10872 if (netdev_name_in_use(&init_net, fb_name)) 10873 snprintf(fb_name, IFNAMSIZ, "dev%%d"); 10874 err = dev_change_net_namespace(dev, &init_net, fb_name); 10875 if (err) { 10876 pr_emerg("%s: failed to move %s to init_net: %d\n", 10877 __func__, dev->name, err); 10878 BUG(); 10879 } 10880 } 10881 rtnl_unlock(); 10882 } 10883 10884 static void __net_exit rtnl_lock_unregistering(struct list_head *net_list) 10885 { 10886 /* Return with the rtnl_lock held when there are no network 10887 * devices unregistering in any network namespace in net_list. 10888 */ 10889 struct net *net; 10890 bool unregistering; 10891 DEFINE_WAIT_FUNC(wait, woken_wake_function); 10892 10893 add_wait_queue(&netdev_unregistering_wq, &wait); 10894 for (;;) { 10895 unregistering = false; 10896 rtnl_lock(); 10897 list_for_each_entry(net, net_list, exit_list) { 10898 if (net->dev_unreg_count > 0) { 10899 unregistering = true; 10900 break; 10901 } 10902 } 10903 if (!unregistering) 10904 break; 10905 __rtnl_unlock(); 10906 10907 wait_woken(&wait, TASK_UNINTERRUPTIBLE, MAX_SCHEDULE_TIMEOUT); 10908 } 10909 remove_wait_queue(&netdev_unregistering_wq, &wait); 10910 } 10911 10912 static void __net_exit default_device_exit_batch(struct list_head *net_list) 10913 { 10914 /* At exit all network devices most be removed from a network 10915 * namespace. Do this in the reverse order of registration. 10916 * Do this across as many network namespaces as possible to 10917 * improve batching efficiency. 10918 */ 10919 struct net_device *dev; 10920 struct net *net; 10921 LIST_HEAD(dev_kill_list); 10922 10923 /* To prevent network device cleanup code from dereferencing 10924 * loopback devices or network devices that have been freed 10925 * wait here for all pending unregistrations to complete, 10926 * before unregistring the loopback device and allowing the 10927 * network namespace be freed. 10928 * 10929 * The netdev todo list containing all network devices 10930 * unregistrations that happen in default_device_exit_batch 10931 * will run in the rtnl_unlock() at the end of 10932 * default_device_exit_batch. 10933 */ 10934 rtnl_lock_unregistering(net_list); 10935 list_for_each_entry(net, net_list, exit_list) { 10936 for_each_netdev_reverse(net, dev) { 10937 if (dev->rtnl_link_ops && dev->rtnl_link_ops->dellink) 10938 dev->rtnl_link_ops->dellink(dev, &dev_kill_list); 10939 else 10940 unregister_netdevice_queue(dev, &dev_kill_list); 10941 } 10942 } 10943 unregister_netdevice_many(&dev_kill_list); 10944 rtnl_unlock(); 10945 } 10946 10947 static struct pernet_operations __net_initdata default_device_ops = { 10948 .exit = default_device_exit, 10949 .exit_batch = default_device_exit_batch, 10950 }; 10951 10952 /* 10953 * Initialize the DEV module. At boot time this walks the device list and 10954 * unhooks any devices that fail to initialise (normally hardware not 10955 * present) and leaves us with a valid list of present and active devices. 10956 * 10957 */ 10958 10959 /* 10960 * This is called single threaded during boot, so no need 10961 * to take the rtnl semaphore. 10962 */ 10963 static int __init net_dev_init(void) 10964 { 10965 int i, rc = -ENOMEM; 10966 10967 BUG_ON(!dev_boot_phase); 10968 10969 if (dev_proc_init()) 10970 goto out; 10971 10972 if (netdev_kobject_init()) 10973 goto out; 10974 10975 INIT_LIST_HEAD(&ptype_all); 10976 for (i = 0; i < PTYPE_HASH_SIZE; i++) 10977 INIT_LIST_HEAD(&ptype_base[i]); 10978 10979 if (register_pernet_subsys(&netdev_net_ops)) 10980 goto out; 10981 10982 /* 10983 * Initialise the packet receive queues. 10984 */ 10985 10986 for_each_possible_cpu(i) { 10987 struct work_struct *flush = per_cpu_ptr(&flush_works, i); 10988 struct softnet_data *sd = &per_cpu(softnet_data, i); 10989 10990 INIT_WORK(flush, flush_backlog); 10991 10992 skb_queue_head_init(&sd->input_pkt_queue); 10993 skb_queue_head_init(&sd->process_queue); 10994 #ifdef CONFIG_XFRM_OFFLOAD 10995 skb_queue_head_init(&sd->xfrm_backlog); 10996 #endif 10997 INIT_LIST_HEAD(&sd->poll_list); 10998 sd->output_queue_tailp = &sd->output_queue; 10999 #ifdef CONFIG_RPS 11000 INIT_CSD(&sd->csd, rps_trigger_softirq, sd); 11001 sd->cpu = i; 11002 #endif 11003 11004 init_gro_hash(&sd->backlog); 11005 sd->backlog.poll = process_backlog; 11006 sd->backlog.weight = weight_p; 11007 } 11008 11009 dev_boot_phase = 0; 11010 11011 /* The loopback device is special if any other network devices 11012 * is present in a network namespace the loopback device must 11013 * be present. Since we now dynamically allocate and free the 11014 * loopback device ensure this invariant is maintained by 11015 * keeping the loopback device as the first device on the 11016 * list of network devices. Ensuring the loopback devices 11017 * is the first device that appears and the last network device 11018 * that disappears. 11019 */ 11020 if (register_pernet_device(&loopback_net_ops)) 11021 goto out; 11022 11023 if (register_pernet_device(&default_device_ops)) 11024 goto out; 11025 11026 open_softirq(NET_TX_SOFTIRQ, net_tx_action); 11027 open_softirq(NET_RX_SOFTIRQ, net_rx_action); 11028 11029 rc = cpuhp_setup_state_nocalls(CPUHP_NET_DEV_DEAD, "net/dev:dead", 11030 NULL, dev_cpu_dead); 11031 WARN_ON(rc < 0); 11032 rc = 0; 11033 out: 11034 return rc; 11035 } 11036 11037 subsys_initcall(net_dev_init); 11038