1 /* 2 * NET3 Protocol independent device support routines. 3 * 4 * This program is free software; you can redistribute it and/or 5 * modify it under the terms of the GNU General Public License 6 * as published by the Free Software Foundation; either version 7 * 2 of the License, or (at your option) any later version. 8 * 9 * Derived from the non IP parts of dev.c 1.0.19 10 * Authors: Ross Biro 11 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG> 12 * Mark Evans, <evansmp@uhura.aston.ac.uk> 13 * 14 * Additional Authors: 15 * Florian la Roche <rzsfl@rz.uni-sb.de> 16 * Alan Cox <gw4pts@gw4pts.ampr.org> 17 * David Hinds <dahinds@users.sourceforge.net> 18 * Alexey Kuznetsov <kuznet@ms2.inr.ac.ru> 19 * Adam Sulmicki <adam@cfar.umd.edu> 20 * Pekka Riikonen <priikone@poesidon.pspt.fi> 21 * 22 * Changes: 23 * D.J. Barrow : Fixed bug where dev->refcnt gets set 24 * to 2 if register_netdev gets called 25 * before net_dev_init & also removed a 26 * few lines of code in the process. 27 * Alan Cox : device private ioctl copies fields back. 28 * Alan Cox : Transmit queue code does relevant 29 * stunts to keep the queue safe. 30 * Alan Cox : Fixed double lock. 31 * Alan Cox : Fixed promisc NULL pointer trap 32 * ???????? : Support the full private ioctl range 33 * Alan Cox : Moved ioctl permission check into 34 * drivers 35 * Tim Kordas : SIOCADDMULTI/SIOCDELMULTI 36 * Alan Cox : 100 backlog just doesn't cut it when 37 * you start doing multicast video 8) 38 * Alan Cox : Rewrote net_bh and list manager. 39 * Alan Cox : Fix ETH_P_ALL echoback lengths. 40 * Alan Cox : Took out transmit every packet pass 41 * Saved a few bytes in the ioctl handler 42 * Alan Cox : Network driver sets packet type before 43 * calling netif_rx. Saves a function 44 * call a packet. 45 * Alan Cox : Hashed net_bh() 46 * Richard Kooijman: Timestamp fixes. 47 * Alan Cox : Wrong field in SIOCGIFDSTADDR 48 * Alan Cox : Device lock protection. 49 * Alan Cox : Fixed nasty side effect of device close 50 * changes. 51 * Rudi Cilibrasi : Pass the right thing to 52 * set_mac_address() 53 * Dave Miller : 32bit quantity for the device lock to 54 * make it work out on a Sparc. 55 * Bjorn Ekwall : Added KERNELD hack. 56 * Alan Cox : Cleaned up the backlog initialise. 57 * Craig Metz : SIOCGIFCONF fix if space for under 58 * 1 device. 59 * Thomas Bogendoerfer : Return ENODEV for dev_open, if there 60 * is no device open function. 61 * Andi Kleen : Fix error reporting for SIOCGIFCONF 62 * Michael Chastain : Fix signed/unsigned for SIOCGIFCONF 63 * Cyrus Durgin : Cleaned for KMOD 64 * Adam Sulmicki : Bug Fix : Network Device Unload 65 * A network device unload needs to purge 66 * the backlog queue. 67 * Paul Rusty Russell : SIOCSIFNAME 68 * Pekka Riikonen : Netdev boot-time settings code 69 * Andrew Morton : Make unregister_netdevice wait 70 * indefinitely on dev->refcnt 71 * J Hadi Salim : - Backlog queue sampling 72 * - netif_rx() feedback 73 */ 74 75 #include <asm/uaccess.h> 76 #include <asm/system.h> 77 #include <linux/bitops.h> 78 #include <linux/capability.h> 79 #include <linux/cpu.h> 80 #include <linux/types.h> 81 #include <linux/kernel.h> 82 #include <linux/hash.h> 83 #include <linux/slab.h> 84 #include <linux/sched.h> 85 #include <linux/mutex.h> 86 #include <linux/string.h> 87 #include <linux/mm.h> 88 #include <linux/socket.h> 89 #include <linux/sockios.h> 90 #include <linux/errno.h> 91 #include <linux/interrupt.h> 92 #include <linux/if_ether.h> 93 #include <linux/netdevice.h> 94 #include <linux/etherdevice.h> 95 #include <linux/ethtool.h> 96 #include <linux/notifier.h> 97 #include <linux/skbuff.h> 98 #include <net/net_namespace.h> 99 #include <net/sock.h> 100 #include <linux/rtnetlink.h> 101 #include <linux/proc_fs.h> 102 #include <linux/seq_file.h> 103 #include <linux/stat.h> 104 #include <linux/if_bridge.h> 105 #include <linux/if_macvlan.h> 106 #include <net/dst.h> 107 #include <net/pkt_sched.h> 108 #include <net/checksum.h> 109 #include <net/xfrm.h> 110 #include <linux/highmem.h> 111 #include <linux/init.h> 112 #include <linux/kmod.h> 113 #include <linux/module.h> 114 #include <linux/netpoll.h> 115 #include <linux/rcupdate.h> 116 #include <linux/delay.h> 117 #include <net/wext.h> 118 #include <net/iw_handler.h> 119 #include <asm/current.h> 120 #include <linux/audit.h> 121 #include <linux/dmaengine.h> 122 #include <linux/err.h> 123 #include <linux/ctype.h> 124 #include <linux/if_arp.h> 125 #include <linux/if_vlan.h> 126 #include <linux/ip.h> 127 #include <net/ip.h> 128 #include <linux/ipv6.h> 129 #include <linux/in.h> 130 #include <linux/jhash.h> 131 #include <linux/random.h> 132 #include <trace/events/napi.h> 133 #include <linux/pci.h> 134 135 #include "net-sysfs.h" 136 137 /* Instead of increasing this, you should create a hash table. */ 138 #define MAX_GRO_SKBS 8 139 140 /* This should be increased if a protocol with a bigger head is added. */ 141 #define GRO_MAX_HEAD (MAX_HEADER + 128) 142 143 /* 144 * The list of packet types we will receive (as opposed to discard) 145 * and the routines to invoke. 146 * 147 * Why 16. Because with 16 the only overlap we get on a hash of the 148 * low nibble of the protocol value is RARP/SNAP/X.25. 149 * 150 * NOTE: That is no longer true with the addition of VLAN tags. Not 151 * sure which should go first, but I bet it won't make much 152 * difference if we are running VLANs. The good news is that 153 * this protocol won't be in the list unless compiled in, so 154 * the average user (w/out VLANs) will not be adversely affected. 155 * --BLG 156 * 157 * 0800 IP 158 * 8100 802.1Q VLAN 159 * 0001 802.3 160 * 0002 AX.25 161 * 0004 802.2 162 * 8035 RARP 163 * 0005 SNAP 164 * 0805 X.25 165 * 0806 ARP 166 * 8137 IPX 167 * 0009 Localtalk 168 * 86DD IPv6 169 */ 170 171 #define PTYPE_HASH_SIZE (16) 172 #define PTYPE_HASH_MASK (PTYPE_HASH_SIZE - 1) 173 174 static DEFINE_SPINLOCK(ptype_lock); 175 static struct list_head ptype_base[PTYPE_HASH_SIZE] __read_mostly; 176 static struct list_head ptype_all __read_mostly; /* Taps */ 177 178 /* 179 * The @dev_base_head list is protected by @dev_base_lock and the rtnl 180 * semaphore. 181 * 182 * Pure readers hold dev_base_lock for reading, or rcu_read_lock() 183 * 184 * Writers must hold the rtnl semaphore while they loop through the 185 * dev_base_head list, and hold dev_base_lock for writing when they do the 186 * actual updates. This allows pure readers to access the list even 187 * while a writer is preparing to update it. 188 * 189 * To put it another way, dev_base_lock is held for writing only to 190 * protect against pure readers; the rtnl semaphore provides the 191 * protection against other writers. 192 * 193 * See, for example usages, register_netdevice() and 194 * unregister_netdevice(), which must be called with the rtnl 195 * semaphore held. 196 */ 197 DEFINE_RWLOCK(dev_base_lock); 198 EXPORT_SYMBOL(dev_base_lock); 199 200 static inline struct hlist_head *dev_name_hash(struct net *net, const char *name) 201 { 202 unsigned hash = full_name_hash(name, strnlen(name, IFNAMSIZ)); 203 return &net->dev_name_head[hash_32(hash, NETDEV_HASHBITS)]; 204 } 205 206 static inline struct hlist_head *dev_index_hash(struct net *net, int ifindex) 207 { 208 return &net->dev_index_head[ifindex & (NETDEV_HASHENTRIES - 1)]; 209 } 210 211 static inline void rps_lock(struct softnet_data *sd) 212 { 213 #ifdef CONFIG_RPS 214 spin_lock(&sd->input_pkt_queue.lock); 215 #endif 216 } 217 218 static inline void rps_unlock(struct softnet_data *sd) 219 { 220 #ifdef CONFIG_RPS 221 spin_unlock(&sd->input_pkt_queue.lock); 222 #endif 223 } 224 225 /* Device list insertion */ 226 static int list_netdevice(struct net_device *dev) 227 { 228 struct net *net = dev_net(dev); 229 230 ASSERT_RTNL(); 231 232 write_lock_bh(&dev_base_lock); 233 list_add_tail_rcu(&dev->dev_list, &net->dev_base_head); 234 hlist_add_head_rcu(&dev->name_hlist, dev_name_hash(net, dev->name)); 235 hlist_add_head_rcu(&dev->index_hlist, 236 dev_index_hash(net, dev->ifindex)); 237 write_unlock_bh(&dev_base_lock); 238 return 0; 239 } 240 241 /* Device list removal 242 * caller must respect a RCU grace period before freeing/reusing dev 243 */ 244 static void unlist_netdevice(struct net_device *dev) 245 { 246 ASSERT_RTNL(); 247 248 /* Unlink dev from the device chain */ 249 write_lock_bh(&dev_base_lock); 250 list_del_rcu(&dev->dev_list); 251 hlist_del_rcu(&dev->name_hlist); 252 hlist_del_rcu(&dev->index_hlist); 253 write_unlock_bh(&dev_base_lock); 254 } 255 256 /* 257 * Our notifier list 258 */ 259 260 static RAW_NOTIFIER_HEAD(netdev_chain); 261 262 /* 263 * Device drivers call our routines to queue packets here. We empty the 264 * queue in the local softnet handler. 265 */ 266 267 DEFINE_PER_CPU_ALIGNED(struct softnet_data, softnet_data); 268 EXPORT_PER_CPU_SYMBOL(softnet_data); 269 270 #ifdef CONFIG_LOCKDEP 271 /* 272 * register_netdevice() inits txq->_xmit_lock and sets lockdep class 273 * according to dev->type 274 */ 275 static const unsigned short netdev_lock_type[] = 276 {ARPHRD_NETROM, ARPHRD_ETHER, ARPHRD_EETHER, ARPHRD_AX25, 277 ARPHRD_PRONET, ARPHRD_CHAOS, ARPHRD_IEEE802, ARPHRD_ARCNET, 278 ARPHRD_APPLETLK, ARPHRD_DLCI, ARPHRD_ATM, ARPHRD_METRICOM, 279 ARPHRD_IEEE1394, ARPHRD_EUI64, ARPHRD_INFINIBAND, ARPHRD_SLIP, 280 ARPHRD_CSLIP, ARPHRD_SLIP6, ARPHRD_CSLIP6, ARPHRD_RSRVD, 281 ARPHRD_ADAPT, ARPHRD_ROSE, ARPHRD_X25, ARPHRD_HWX25, 282 ARPHRD_PPP, ARPHRD_CISCO, ARPHRD_LAPB, ARPHRD_DDCMP, 283 ARPHRD_RAWHDLC, ARPHRD_TUNNEL, ARPHRD_TUNNEL6, ARPHRD_FRAD, 284 ARPHRD_SKIP, ARPHRD_LOOPBACK, ARPHRD_LOCALTLK, ARPHRD_FDDI, 285 ARPHRD_BIF, ARPHRD_SIT, ARPHRD_IPDDP, ARPHRD_IPGRE, 286 ARPHRD_PIMREG, ARPHRD_HIPPI, ARPHRD_ASH, ARPHRD_ECONET, 287 ARPHRD_IRDA, ARPHRD_FCPP, ARPHRD_FCAL, ARPHRD_FCPL, 288 ARPHRD_FCFABRIC, ARPHRD_IEEE802_TR, ARPHRD_IEEE80211, 289 ARPHRD_IEEE80211_PRISM, ARPHRD_IEEE80211_RADIOTAP, ARPHRD_PHONET, 290 ARPHRD_PHONET_PIPE, ARPHRD_IEEE802154, 291 ARPHRD_VOID, ARPHRD_NONE}; 292 293 static const char *const netdev_lock_name[] = 294 {"_xmit_NETROM", "_xmit_ETHER", "_xmit_EETHER", "_xmit_AX25", 295 "_xmit_PRONET", "_xmit_CHAOS", "_xmit_IEEE802", "_xmit_ARCNET", 296 "_xmit_APPLETLK", "_xmit_DLCI", "_xmit_ATM", "_xmit_METRICOM", 297 "_xmit_IEEE1394", "_xmit_EUI64", "_xmit_INFINIBAND", "_xmit_SLIP", 298 "_xmit_CSLIP", "_xmit_SLIP6", "_xmit_CSLIP6", "_xmit_RSRVD", 299 "_xmit_ADAPT", "_xmit_ROSE", "_xmit_X25", "_xmit_HWX25", 300 "_xmit_PPP", "_xmit_CISCO", "_xmit_LAPB", "_xmit_DDCMP", 301 "_xmit_RAWHDLC", "_xmit_TUNNEL", "_xmit_TUNNEL6", "_xmit_FRAD", 302 "_xmit_SKIP", "_xmit_LOOPBACK", "_xmit_LOCALTLK", "_xmit_FDDI", 303 "_xmit_BIF", "_xmit_SIT", "_xmit_IPDDP", "_xmit_IPGRE", 304 "_xmit_PIMREG", "_xmit_HIPPI", "_xmit_ASH", "_xmit_ECONET", 305 "_xmit_IRDA", "_xmit_FCPP", "_xmit_FCAL", "_xmit_FCPL", 306 "_xmit_FCFABRIC", "_xmit_IEEE802_TR", "_xmit_IEEE80211", 307 "_xmit_IEEE80211_PRISM", "_xmit_IEEE80211_RADIOTAP", "_xmit_PHONET", 308 "_xmit_PHONET_PIPE", "_xmit_IEEE802154", 309 "_xmit_VOID", "_xmit_NONE"}; 310 311 static struct lock_class_key netdev_xmit_lock_key[ARRAY_SIZE(netdev_lock_type)]; 312 static struct lock_class_key netdev_addr_lock_key[ARRAY_SIZE(netdev_lock_type)]; 313 314 static inline unsigned short netdev_lock_pos(unsigned short dev_type) 315 { 316 int i; 317 318 for (i = 0; i < ARRAY_SIZE(netdev_lock_type); i++) 319 if (netdev_lock_type[i] == dev_type) 320 return i; 321 /* the last key is used by default */ 322 return ARRAY_SIZE(netdev_lock_type) - 1; 323 } 324 325 static inline void netdev_set_xmit_lockdep_class(spinlock_t *lock, 326 unsigned short dev_type) 327 { 328 int i; 329 330 i = netdev_lock_pos(dev_type); 331 lockdep_set_class_and_name(lock, &netdev_xmit_lock_key[i], 332 netdev_lock_name[i]); 333 } 334 335 static inline void netdev_set_addr_lockdep_class(struct net_device *dev) 336 { 337 int i; 338 339 i = netdev_lock_pos(dev->type); 340 lockdep_set_class_and_name(&dev->addr_list_lock, 341 &netdev_addr_lock_key[i], 342 netdev_lock_name[i]); 343 } 344 #else 345 static inline void netdev_set_xmit_lockdep_class(spinlock_t *lock, 346 unsigned short dev_type) 347 { 348 } 349 static inline void netdev_set_addr_lockdep_class(struct net_device *dev) 350 { 351 } 352 #endif 353 354 /******************************************************************************* 355 356 Protocol management and registration routines 357 358 *******************************************************************************/ 359 360 /* 361 * Add a protocol ID to the list. Now that the input handler is 362 * smarter we can dispense with all the messy stuff that used to be 363 * here. 364 * 365 * BEWARE!!! Protocol handlers, mangling input packets, 366 * MUST BE last in hash buckets and checking protocol handlers 367 * MUST start from promiscuous ptype_all chain in net_bh. 368 * It is true now, do not change it. 369 * Explanation follows: if protocol handler, mangling packet, will 370 * be the first on list, it is not able to sense, that packet 371 * is cloned and should be copied-on-write, so that it will 372 * change it and subsequent readers will get broken packet. 373 * --ANK (980803) 374 */ 375 376 /** 377 * dev_add_pack - add packet handler 378 * @pt: packet type declaration 379 * 380 * Add a protocol handler to the networking stack. The passed &packet_type 381 * is linked into kernel lists and may not be freed until it has been 382 * removed from the kernel lists. 383 * 384 * This call does not sleep therefore it can not 385 * guarantee all CPU's that are in middle of receiving packets 386 * will see the new packet type (until the next received packet). 387 */ 388 389 void dev_add_pack(struct packet_type *pt) 390 { 391 int hash; 392 393 spin_lock_bh(&ptype_lock); 394 if (pt->type == htons(ETH_P_ALL)) 395 list_add_rcu(&pt->list, &ptype_all); 396 else { 397 hash = ntohs(pt->type) & PTYPE_HASH_MASK; 398 list_add_rcu(&pt->list, &ptype_base[hash]); 399 } 400 spin_unlock_bh(&ptype_lock); 401 } 402 EXPORT_SYMBOL(dev_add_pack); 403 404 /** 405 * __dev_remove_pack - remove packet handler 406 * @pt: packet type declaration 407 * 408 * Remove a protocol handler that was previously added to the kernel 409 * protocol handlers by dev_add_pack(). The passed &packet_type is removed 410 * from the kernel lists and can be freed or reused once this function 411 * returns. 412 * 413 * The packet type might still be in use by receivers 414 * and must not be freed until after all the CPU's have gone 415 * through a quiescent state. 416 */ 417 void __dev_remove_pack(struct packet_type *pt) 418 { 419 struct list_head *head; 420 struct packet_type *pt1; 421 422 spin_lock_bh(&ptype_lock); 423 424 if (pt->type == htons(ETH_P_ALL)) 425 head = &ptype_all; 426 else 427 head = &ptype_base[ntohs(pt->type) & PTYPE_HASH_MASK]; 428 429 list_for_each_entry(pt1, head, list) { 430 if (pt == pt1) { 431 list_del_rcu(&pt->list); 432 goto out; 433 } 434 } 435 436 printk(KERN_WARNING "dev_remove_pack: %p not found.\n", pt); 437 out: 438 spin_unlock_bh(&ptype_lock); 439 } 440 EXPORT_SYMBOL(__dev_remove_pack); 441 442 /** 443 * dev_remove_pack - remove packet handler 444 * @pt: packet type declaration 445 * 446 * Remove a protocol handler that was previously added to the kernel 447 * protocol handlers by dev_add_pack(). The passed &packet_type is removed 448 * from the kernel lists and can be freed or reused once this function 449 * returns. 450 * 451 * This call sleeps to guarantee that no CPU is looking at the packet 452 * type after return. 453 */ 454 void dev_remove_pack(struct packet_type *pt) 455 { 456 __dev_remove_pack(pt); 457 458 synchronize_net(); 459 } 460 EXPORT_SYMBOL(dev_remove_pack); 461 462 /****************************************************************************** 463 464 Device Boot-time Settings Routines 465 466 *******************************************************************************/ 467 468 /* Boot time configuration table */ 469 static struct netdev_boot_setup dev_boot_setup[NETDEV_BOOT_SETUP_MAX]; 470 471 /** 472 * netdev_boot_setup_add - add new setup entry 473 * @name: name of the device 474 * @map: configured settings for the device 475 * 476 * Adds new setup entry to the dev_boot_setup list. The function 477 * returns 0 on error and 1 on success. This is a generic routine to 478 * all netdevices. 479 */ 480 static int netdev_boot_setup_add(char *name, struct ifmap *map) 481 { 482 struct netdev_boot_setup *s; 483 int i; 484 485 s = dev_boot_setup; 486 for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++) { 487 if (s[i].name[0] == '\0' || s[i].name[0] == ' ') { 488 memset(s[i].name, 0, sizeof(s[i].name)); 489 strlcpy(s[i].name, name, IFNAMSIZ); 490 memcpy(&s[i].map, map, sizeof(s[i].map)); 491 break; 492 } 493 } 494 495 return i >= NETDEV_BOOT_SETUP_MAX ? 0 : 1; 496 } 497 498 /** 499 * netdev_boot_setup_check - check boot time settings 500 * @dev: the netdevice 501 * 502 * Check boot time settings for the device. 503 * The found settings are set for the device to be used 504 * later in the device probing. 505 * Returns 0 if no settings found, 1 if they are. 506 */ 507 int netdev_boot_setup_check(struct net_device *dev) 508 { 509 struct netdev_boot_setup *s = dev_boot_setup; 510 int i; 511 512 for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++) { 513 if (s[i].name[0] != '\0' && s[i].name[0] != ' ' && 514 !strcmp(dev->name, s[i].name)) { 515 dev->irq = s[i].map.irq; 516 dev->base_addr = s[i].map.base_addr; 517 dev->mem_start = s[i].map.mem_start; 518 dev->mem_end = s[i].map.mem_end; 519 return 1; 520 } 521 } 522 return 0; 523 } 524 EXPORT_SYMBOL(netdev_boot_setup_check); 525 526 527 /** 528 * netdev_boot_base - get address from boot time settings 529 * @prefix: prefix for network device 530 * @unit: id for network device 531 * 532 * Check boot time settings for the base address of device. 533 * The found settings are set for the device to be used 534 * later in the device probing. 535 * Returns 0 if no settings found. 536 */ 537 unsigned long netdev_boot_base(const char *prefix, int unit) 538 { 539 const struct netdev_boot_setup *s = dev_boot_setup; 540 char name[IFNAMSIZ]; 541 int i; 542 543 sprintf(name, "%s%d", prefix, unit); 544 545 /* 546 * If device already registered then return base of 1 547 * to indicate not to probe for this interface 548 */ 549 if (__dev_get_by_name(&init_net, name)) 550 return 1; 551 552 for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++) 553 if (!strcmp(name, s[i].name)) 554 return s[i].map.base_addr; 555 return 0; 556 } 557 558 /* 559 * Saves at boot time configured settings for any netdevice. 560 */ 561 int __init netdev_boot_setup(char *str) 562 { 563 int ints[5]; 564 struct ifmap map; 565 566 str = get_options(str, ARRAY_SIZE(ints), ints); 567 if (!str || !*str) 568 return 0; 569 570 /* Save settings */ 571 memset(&map, 0, sizeof(map)); 572 if (ints[0] > 0) 573 map.irq = ints[1]; 574 if (ints[0] > 1) 575 map.base_addr = ints[2]; 576 if (ints[0] > 2) 577 map.mem_start = ints[3]; 578 if (ints[0] > 3) 579 map.mem_end = ints[4]; 580 581 /* Add new entry to the list */ 582 return netdev_boot_setup_add(str, &map); 583 } 584 585 __setup("netdev=", netdev_boot_setup); 586 587 /******************************************************************************* 588 589 Device Interface Subroutines 590 591 *******************************************************************************/ 592 593 /** 594 * __dev_get_by_name - find a device by its name 595 * @net: the applicable net namespace 596 * @name: name to find 597 * 598 * Find an interface by name. Must be called under RTNL semaphore 599 * or @dev_base_lock. If the name is found a pointer to the device 600 * is returned. If the name is not found then %NULL is returned. The 601 * reference counters are not incremented so the caller must be 602 * careful with locks. 603 */ 604 605 struct net_device *__dev_get_by_name(struct net *net, const char *name) 606 { 607 struct hlist_node *p; 608 struct net_device *dev; 609 struct hlist_head *head = dev_name_hash(net, name); 610 611 hlist_for_each_entry(dev, p, head, name_hlist) 612 if (!strncmp(dev->name, name, IFNAMSIZ)) 613 return dev; 614 615 return NULL; 616 } 617 EXPORT_SYMBOL(__dev_get_by_name); 618 619 /** 620 * dev_get_by_name_rcu - find a device by its name 621 * @net: the applicable net namespace 622 * @name: name to find 623 * 624 * Find an interface by name. 625 * If the name is found a pointer to the device is returned. 626 * If the name is not found then %NULL is returned. 627 * The reference counters are not incremented so the caller must be 628 * careful with locks. The caller must hold RCU lock. 629 */ 630 631 struct net_device *dev_get_by_name_rcu(struct net *net, const char *name) 632 { 633 struct hlist_node *p; 634 struct net_device *dev; 635 struct hlist_head *head = dev_name_hash(net, name); 636 637 hlist_for_each_entry_rcu(dev, p, head, name_hlist) 638 if (!strncmp(dev->name, name, IFNAMSIZ)) 639 return dev; 640 641 return NULL; 642 } 643 EXPORT_SYMBOL(dev_get_by_name_rcu); 644 645 /** 646 * dev_get_by_name - find a device by its name 647 * @net: the applicable net namespace 648 * @name: name to find 649 * 650 * Find an interface by name. This can be called from any 651 * context and does its own locking. The returned handle has 652 * the usage count incremented and the caller must use dev_put() to 653 * release it when it is no longer needed. %NULL is returned if no 654 * matching device is found. 655 */ 656 657 struct net_device *dev_get_by_name(struct net *net, const char *name) 658 { 659 struct net_device *dev; 660 661 rcu_read_lock(); 662 dev = dev_get_by_name_rcu(net, name); 663 if (dev) 664 dev_hold(dev); 665 rcu_read_unlock(); 666 return dev; 667 } 668 EXPORT_SYMBOL(dev_get_by_name); 669 670 /** 671 * __dev_get_by_index - find a device by its ifindex 672 * @net: the applicable net namespace 673 * @ifindex: index of device 674 * 675 * Search for an interface by index. Returns %NULL if the device 676 * is not found or a pointer to the device. The device has not 677 * had its reference counter increased so the caller must be careful 678 * about locking. The caller must hold either the RTNL semaphore 679 * or @dev_base_lock. 680 */ 681 682 struct net_device *__dev_get_by_index(struct net *net, int ifindex) 683 { 684 struct hlist_node *p; 685 struct net_device *dev; 686 struct hlist_head *head = dev_index_hash(net, ifindex); 687 688 hlist_for_each_entry(dev, p, head, index_hlist) 689 if (dev->ifindex == ifindex) 690 return dev; 691 692 return NULL; 693 } 694 EXPORT_SYMBOL(__dev_get_by_index); 695 696 /** 697 * dev_get_by_index_rcu - find a device by its ifindex 698 * @net: the applicable net namespace 699 * @ifindex: index of device 700 * 701 * Search for an interface by index. Returns %NULL if the device 702 * is not found or a pointer to the device. The device has not 703 * had its reference counter increased so the caller must be careful 704 * about locking. The caller must hold RCU lock. 705 */ 706 707 struct net_device *dev_get_by_index_rcu(struct net *net, int ifindex) 708 { 709 struct hlist_node *p; 710 struct net_device *dev; 711 struct hlist_head *head = dev_index_hash(net, ifindex); 712 713 hlist_for_each_entry_rcu(dev, p, head, index_hlist) 714 if (dev->ifindex == ifindex) 715 return dev; 716 717 return NULL; 718 } 719 EXPORT_SYMBOL(dev_get_by_index_rcu); 720 721 722 /** 723 * dev_get_by_index - find a device by its ifindex 724 * @net: the applicable net namespace 725 * @ifindex: index of device 726 * 727 * Search for an interface by index. Returns NULL if the device 728 * is not found or a pointer to the device. The device returned has 729 * had a reference added and the pointer is safe until the user calls 730 * dev_put to indicate they have finished with it. 731 */ 732 733 struct net_device *dev_get_by_index(struct net *net, int ifindex) 734 { 735 struct net_device *dev; 736 737 rcu_read_lock(); 738 dev = dev_get_by_index_rcu(net, ifindex); 739 if (dev) 740 dev_hold(dev); 741 rcu_read_unlock(); 742 return dev; 743 } 744 EXPORT_SYMBOL(dev_get_by_index); 745 746 /** 747 * dev_getbyhwaddr - find a device by its hardware address 748 * @net: the applicable net namespace 749 * @type: media type of device 750 * @ha: hardware address 751 * 752 * Search for an interface by MAC address. Returns NULL if the device 753 * is not found or a pointer to the device. The caller must hold the 754 * rtnl semaphore. The returned device has not had its ref count increased 755 * and the caller must therefore be careful about locking 756 * 757 * BUGS: 758 * If the API was consistent this would be __dev_get_by_hwaddr 759 */ 760 761 struct net_device *dev_getbyhwaddr(struct net *net, unsigned short type, char *ha) 762 { 763 struct net_device *dev; 764 765 ASSERT_RTNL(); 766 767 for_each_netdev(net, dev) 768 if (dev->type == type && 769 !memcmp(dev->dev_addr, ha, dev->addr_len)) 770 return dev; 771 772 return NULL; 773 } 774 EXPORT_SYMBOL(dev_getbyhwaddr); 775 776 struct net_device *__dev_getfirstbyhwtype(struct net *net, unsigned short type) 777 { 778 struct net_device *dev; 779 780 ASSERT_RTNL(); 781 for_each_netdev(net, dev) 782 if (dev->type == type) 783 return dev; 784 785 return NULL; 786 } 787 EXPORT_SYMBOL(__dev_getfirstbyhwtype); 788 789 struct net_device *dev_getfirstbyhwtype(struct net *net, unsigned short type) 790 { 791 struct net_device *dev, *ret = NULL; 792 793 rcu_read_lock(); 794 for_each_netdev_rcu(net, dev) 795 if (dev->type == type) { 796 dev_hold(dev); 797 ret = dev; 798 break; 799 } 800 rcu_read_unlock(); 801 return ret; 802 } 803 EXPORT_SYMBOL(dev_getfirstbyhwtype); 804 805 /** 806 * dev_get_by_flags - find any device with given flags 807 * @net: the applicable net namespace 808 * @if_flags: IFF_* values 809 * @mask: bitmask of bits in if_flags to check 810 * 811 * Search for any interface with the given flags. Returns NULL if a device 812 * is not found or a pointer to the device. The device returned has 813 * had a reference added and the pointer is safe until the user calls 814 * dev_put to indicate they have finished with it. 815 */ 816 817 struct net_device *dev_get_by_flags(struct net *net, unsigned short if_flags, 818 unsigned short mask) 819 { 820 struct net_device *dev, *ret; 821 822 ret = NULL; 823 rcu_read_lock(); 824 for_each_netdev_rcu(net, dev) { 825 if (((dev->flags ^ if_flags) & mask) == 0) { 826 dev_hold(dev); 827 ret = dev; 828 break; 829 } 830 } 831 rcu_read_unlock(); 832 return ret; 833 } 834 EXPORT_SYMBOL(dev_get_by_flags); 835 836 /** 837 * dev_valid_name - check if name is okay for network device 838 * @name: name string 839 * 840 * Network device names need to be valid file names to 841 * to allow sysfs to work. We also disallow any kind of 842 * whitespace. 843 */ 844 int dev_valid_name(const char *name) 845 { 846 if (*name == '\0') 847 return 0; 848 if (strlen(name) >= IFNAMSIZ) 849 return 0; 850 if (!strcmp(name, ".") || !strcmp(name, "..")) 851 return 0; 852 853 while (*name) { 854 if (*name == '/' || isspace(*name)) 855 return 0; 856 name++; 857 } 858 return 1; 859 } 860 EXPORT_SYMBOL(dev_valid_name); 861 862 /** 863 * __dev_alloc_name - allocate a name for a device 864 * @net: network namespace to allocate the device name in 865 * @name: name format string 866 * @buf: scratch buffer and result name string 867 * 868 * Passed a format string - eg "lt%d" it will try and find a suitable 869 * id. It scans list of devices to build up a free map, then chooses 870 * the first empty slot. The caller must hold the dev_base or rtnl lock 871 * while allocating the name and adding the device in order to avoid 872 * duplicates. 873 * Limited to bits_per_byte * page size devices (ie 32K on most platforms). 874 * Returns the number of the unit assigned or a negative errno code. 875 */ 876 877 static int __dev_alloc_name(struct net *net, const char *name, char *buf) 878 { 879 int i = 0; 880 const char *p; 881 const int max_netdevices = 8*PAGE_SIZE; 882 unsigned long *inuse; 883 struct net_device *d; 884 885 p = strnchr(name, IFNAMSIZ-1, '%'); 886 if (p) { 887 /* 888 * Verify the string as this thing may have come from 889 * the user. There must be either one "%d" and no other "%" 890 * characters. 891 */ 892 if (p[1] != 'd' || strchr(p + 2, '%')) 893 return -EINVAL; 894 895 /* Use one page as a bit array of possible slots */ 896 inuse = (unsigned long *) get_zeroed_page(GFP_ATOMIC); 897 if (!inuse) 898 return -ENOMEM; 899 900 for_each_netdev(net, d) { 901 if (!sscanf(d->name, name, &i)) 902 continue; 903 if (i < 0 || i >= max_netdevices) 904 continue; 905 906 /* avoid cases where sscanf is not exact inverse of printf */ 907 snprintf(buf, IFNAMSIZ, name, i); 908 if (!strncmp(buf, d->name, IFNAMSIZ)) 909 set_bit(i, inuse); 910 } 911 912 i = find_first_zero_bit(inuse, max_netdevices); 913 free_page((unsigned long) inuse); 914 } 915 916 if (buf != name) 917 snprintf(buf, IFNAMSIZ, name, i); 918 if (!__dev_get_by_name(net, buf)) 919 return i; 920 921 /* It is possible to run out of possible slots 922 * when the name is long and there isn't enough space left 923 * for the digits, or if all bits are used. 924 */ 925 return -ENFILE; 926 } 927 928 /** 929 * dev_alloc_name - allocate a name for a device 930 * @dev: device 931 * @name: name format string 932 * 933 * Passed a format string - eg "lt%d" it will try and find a suitable 934 * id. It scans list of devices to build up a free map, then chooses 935 * the first empty slot. The caller must hold the dev_base or rtnl lock 936 * while allocating the name and adding the device in order to avoid 937 * duplicates. 938 * Limited to bits_per_byte * page size devices (ie 32K on most platforms). 939 * Returns the number of the unit assigned or a negative errno code. 940 */ 941 942 int dev_alloc_name(struct net_device *dev, const char *name) 943 { 944 char buf[IFNAMSIZ]; 945 struct net *net; 946 int ret; 947 948 BUG_ON(!dev_net(dev)); 949 net = dev_net(dev); 950 ret = __dev_alloc_name(net, name, buf); 951 if (ret >= 0) 952 strlcpy(dev->name, buf, IFNAMSIZ); 953 return ret; 954 } 955 EXPORT_SYMBOL(dev_alloc_name); 956 957 static int dev_get_valid_name(struct net_device *dev, const char *name, bool fmt) 958 { 959 struct net *net; 960 961 BUG_ON(!dev_net(dev)); 962 net = dev_net(dev); 963 964 if (!dev_valid_name(name)) 965 return -EINVAL; 966 967 if (fmt && strchr(name, '%')) 968 return dev_alloc_name(dev, name); 969 else if (__dev_get_by_name(net, name)) 970 return -EEXIST; 971 else if (dev->name != name) 972 strlcpy(dev->name, name, IFNAMSIZ); 973 974 return 0; 975 } 976 977 /** 978 * dev_change_name - change name of a device 979 * @dev: device 980 * @newname: name (or format string) must be at least IFNAMSIZ 981 * 982 * Change name of a device, can pass format strings "eth%d". 983 * for wildcarding. 984 */ 985 int dev_change_name(struct net_device *dev, const char *newname) 986 { 987 char oldname[IFNAMSIZ]; 988 int err = 0; 989 int ret; 990 struct net *net; 991 992 ASSERT_RTNL(); 993 BUG_ON(!dev_net(dev)); 994 995 net = dev_net(dev); 996 if (dev->flags & IFF_UP) 997 return -EBUSY; 998 999 if (strncmp(newname, dev->name, IFNAMSIZ) == 0) 1000 return 0; 1001 1002 memcpy(oldname, dev->name, IFNAMSIZ); 1003 1004 err = dev_get_valid_name(dev, newname, 1); 1005 if (err < 0) 1006 return err; 1007 1008 rollback: 1009 ret = device_rename(&dev->dev, dev->name); 1010 if (ret) { 1011 memcpy(dev->name, oldname, IFNAMSIZ); 1012 return ret; 1013 } 1014 1015 write_lock_bh(&dev_base_lock); 1016 hlist_del(&dev->name_hlist); 1017 write_unlock_bh(&dev_base_lock); 1018 1019 synchronize_rcu(); 1020 1021 write_lock_bh(&dev_base_lock); 1022 hlist_add_head_rcu(&dev->name_hlist, dev_name_hash(net, dev->name)); 1023 write_unlock_bh(&dev_base_lock); 1024 1025 ret = call_netdevice_notifiers(NETDEV_CHANGENAME, dev); 1026 ret = notifier_to_errno(ret); 1027 1028 if (ret) { 1029 /* err >= 0 after dev_alloc_name() or stores the first errno */ 1030 if (err >= 0) { 1031 err = ret; 1032 memcpy(dev->name, oldname, IFNAMSIZ); 1033 goto rollback; 1034 } else { 1035 printk(KERN_ERR 1036 "%s: name change rollback failed: %d.\n", 1037 dev->name, ret); 1038 } 1039 } 1040 1041 return err; 1042 } 1043 1044 /** 1045 * dev_set_alias - change ifalias of a device 1046 * @dev: device 1047 * @alias: name up to IFALIASZ 1048 * @len: limit of bytes to copy from info 1049 * 1050 * Set ifalias for a device, 1051 */ 1052 int dev_set_alias(struct net_device *dev, const char *alias, size_t len) 1053 { 1054 ASSERT_RTNL(); 1055 1056 if (len >= IFALIASZ) 1057 return -EINVAL; 1058 1059 if (!len) { 1060 if (dev->ifalias) { 1061 kfree(dev->ifalias); 1062 dev->ifalias = NULL; 1063 } 1064 return 0; 1065 } 1066 1067 dev->ifalias = krealloc(dev->ifalias, len + 1, GFP_KERNEL); 1068 if (!dev->ifalias) 1069 return -ENOMEM; 1070 1071 strlcpy(dev->ifalias, alias, len+1); 1072 return len; 1073 } 1074 1075 1076 /** 1077 * netdev_features_change - device changes features 1078 * @dev: device to cause notification 1079 * 1080 * Called to indicate a device has changed features. 1081 */ 1082 void netdev_features_change(struct net_device *dev) 1083 { 1084 call_netdevice_notifiers(NETDEV_FEAT_CHANGE, dev); 1085 } 1086 EXPORT_SYMBOL(netdev_features_change); 1087 1088 /** 1089 * netdev_state_change - device changes state 1090 * @dev: device to cause notification 1091 * 1092 * Called to indicate a device has changed state. This function calls 1093 * the notifier chains for netdev_chain and sends a NEWLINK message 1094 * to the routing socket. 1095 */ 1096 void netdev_state_change(struct net_device *dev) 1097 { 1098 if (dev->flags & IFF_UP) { 1099 call_netdevice_notifiers(NETDEV_CHANGE, dev); 1100 rtmsg_ifinfo(RTM_NEWLINK, dev, 0); 1101 } 1102 } 1103 EXPORT_SYMBOL(netdev_state_change); 1104 1105 int netdev_bonding_change(struct net_device *dev, unsigned long event) 1106 { 1107 return call_netdevice_notifiers(event, dev); 1108 } 1109 EXPORT_SYMBOL(netdev_bonding_change); 1110 1111 /** 1112 * dev_load - load a network module 1113 * @net: the applicable net namespace 1114 * @name: name of interface 1115 * 1116 * If a network interface is not present and the process has suitable 1117 * privileges this function loads the module. If module loading is not 1118 * available in this kernel then it becomes a nop. 1119 */ 1120 1121 void dev_load(struct net *net, const char *name) 1122 { 1123 struct net_device *dev; 1124 1125 rcu_read_lock(); 1126 dev = dev_get_by_name_rcu(net, name); 1127 rcu_read_unlock(); 1128 1129 if (!dev && capable(CAP_NET_ADMIN)) 1130 request_module("%s", name); 1131 } 1132 EXPORT_SYMBOL(dev_load); 1133 1134 static int __dev_open(struct net_device *dev) 1135 { 1136 const struct net_device_ops *ops = dev->netdev_ops; 1137 int ret; 1138 1139 ASSERT_RTNL(); 1140 1141 /* 1142 * Is it even present? 1143 */ 1144 if (!netif_device_present(dev)) 1145 return -ENODEV; 1146 1147 ret = call_netdevice_notifiers(NETDEV_PRE_UP, dev); 1148 ret = notifier_to_errno(ret); 1149 if (ret) 1150 return ret; 1151 1152 /* 1153 * Call device private open method 1154 */ 1155 set_bit(__LINK_STATE_START, &dev->state); 1156 1157 if (ops->ndo_validate_addr) 1158 ret = ops->ndo_validate_addr(dev); 1159 1160 if (!ret && ops->ndo_open) 1161 ret = ops->ndo_open(dev); 1162 1163 /* 1164 * If it went open OK then: 1165 */ 1166 1167 if (ret) 1168 clear_bit(__LINK_STATE_START, &dev->state); 1169 else { 1170 /* 1171 * Set the flags. 1172 */ 1173 dev->flags |= IFF_UP; 1174 1175 /* 1176 * Enable NET_DMA 1177 */ 1178 net_dmaengine_get(); 1179 1180 /* 1181 * Initialize multicasting status 1182 */ 1183 dev_set_rx_mode(dev); 1184 1185 /* 1186 * Wakeup transmit queue engine 1187 */ 1188 dev_activate(dev); 1189 } 1190 1191 return ret; 1192 } 1193 1194 /** 1195 * dev_open - prepare an interface for use. 1196 * @dev: device to open 1197 * 1198 * Takes a device from down to up state. The device's private open 1199 * function is invoked and then the multicast lists are loaded. Finally 1200 * the device is moved into the up state and a %NETDEV_UP message is 1201 * sent to the netdev notifier chain. 1202 * 1203 * Calling this function on an active interface is a nop. On a failure 1204 * a negative errno code is returned. 1205 */ 1206 int dev_open(struct net_device *dev) 1207 { 1208 int ret; 1209 1210 /* 1211 * Is it already up? 1212 */ 1213 if (dev->flags & IFF_UP) 1214 return 0; 1215 1216 /* 1217 * Open device 1218 */ 1219 ret = __dev_open(dev); 1220 if (ret < 0) 1221 return ret; 1222 1223 /* 1224 * ... and announce new interface. 1225 */ 1226 rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP|IFF_RUNNING); 1227 call_netdevice_notifiers(NETDEV_UP, dev); 1228 1229 return ret; 1230 } 1231 EXPORT_SYMBOL(dev_open); 1232 1233 static int __dev_close(struct net_device *dev) 1234 { 1235 const struct net_device_ops *ops = dev->netdev_ops; 1236 1237 ASSERT_RTNL(); 1238 might_sleep(); 1239 1240 /* 1241 * Tell people we are going down, so that they can 1242 * prepare to death, when device is still operating. 1243 */ 1244 call_netdevice_notifiers(NETDEV_GOING_DOWN, dev); 1245 1246 clear_bit(__LINK_STATE_START, &dev->state); 1247 1248 /* Synchronize to scheduled poll. We cannot touch poll list, 1249 * it can be even on different cpu. So just clear netif_running(). 1250 * 1251 * dev->stop() will invoke napi_disable() on all of it's 1252 * napi_struct instances on this device. 1253 */ 1254 smp_mb__after_clear_bit(); /* Commit netif_running(). */ 1255 1256 dev_deactivate(dev); 1257 1258 /* 1259 * Call the device specific close. This cannot fail. 1260 * Only if device is UP 1261 * 1262 * We allow it to be called even after a DETACH hot-plug 1263 * event. 1264 */ 1265 if (ops->ndo_stop) 1266 ops->ndo_stop(dev); 1267 1268 /* 1269 * Device is now down. 1270 */ 1271 1272 dev->flags &= ~IFF_UP; 1273 1274 /* 1275 * Shutdown NET_DMA 1276 */ 1277 net_dmaengine_put(); 1278 1279 return 0; 1280 } 1281 1282 /** 1283 * dev_close - shutdown an interface. 1284 * @dev: device to shutdown 1285 * 1286 * This function moves an active device into down state. A 1287 * %NETDEV_GOING_DOWN is sent to the netdev notifier chain. The device 1288 * is then deactivated and finally a %NETDEV_DOWN is sent to the notifier 1289 * chain. 1290 */ 1291 int dev_close(struct net_device *dev) 1292 { 1293 if (!(dev->flags & IFF_UP)) 1294 return 0; 1295 1296 __dev_close(dev); 1297 1298 /* 1299 * Tell people we are down 1300 */ 1301 rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP|IFF_RUNNING); 1302 call_netdevice_notifiers(NETDEV_DOWN, dev); 1303 1304 return 0; 1305 } 1306 EXPORT_SYMBOL(dev_close); 1307 1308 1309 /** 1310 * dev_disable_lro - disable Large Receive Offload on a device 1311 * @dev: device 1312 * 1313 * Disable Large Receive Offload (LRO) on a net device. Must be 1314 * called under RTNL. This is needed if received packets may be 1315 * forwarded to another interface. 1316 */ 1317 void dev_disable_lro(struct net_device *dev) 1318 { 1319 if (dev->ethtool_ops && dev->ethtool_ops->get_flags && 1320 dev->ethtool_ops->set_flags) { 1321 u32 flags = dev->ethtool_ops->get_flags(dev); 1322 if (flags & ETH_FLAG_LRO) { 1323 flags &= ~ETH_FLAG_LRO; 1324 dev->ethtool_ops->set_flags(dev, flags); 1325 } 1326 } 1327 WARN_ON(dev->features & NETIF_F_LRO); 1328 } 1329 EXPORT_SYMBOL(dev_disable_lro); 1330 1331 1332 static int dev_boot_phase = 1; 1333 1334 /* 1335 * Device change register/unregister. These are not inline or static 1336 * as we export them to the world. 1337 */ 1338 1339 /** 1340 * register_netdevice_notifier - register a network notifier block 1341 * @nb: notifier 1342 * 1343 * Register a notifier to be called when network device events occur. 1344 * The notifier passed is linked into the kernel structures and must 1345 * not be reused until it has been unregistered. A negative errno code 1346 * is returned on a failure. 1347 * 1348 * When registered all registration and up events are replayed 1349 * to the new notifier to allow device to have a race free 1350 * view of the network device list. 1351 */ 1352 1353 int register_netdevice_notifier(struct notifier_block *nb) 1354 { 1355 struct net_device *dev; 1356 struct net_device *last; 1357 struct net *net; 1358 int err; 1359 1360 rtnl_lock(); 1361 err = raw_notifier_chain_register(&netdev_chain, nb); 1362 if (err) 1363 goto unlock; 1364 if (dev_boot_phase) 1365 goto unlock; 1366 for_each_net(net) { 1367 for_each_netdev(net, dev) { 1368 err = nb->notifier_call(nb, NETDEV_REGISTER, dev); 1369 err = notifier_to_errno(err); 1370 if (err) 1371 goto rollback; 1372 1373 if (!(dev->flags & IFF_UP)) 1374 continue; 1375 1376 nb->notifier_call(nb, NETDEV_UP, dev); 1377 } 1378 } 1379 1380 unlock: 1381 rtnl_unlock(); 1382 return err; 1383 1384 rollback: 1385 last = dev; 1386 for_each_net(net) { 1387 for_each_netdev(net, dev) { 1388 if (dev == last) 1389 break; 1390 1391 if (dev->flags & IFF_UP) { 1392 nb->notifier_call(nb, NETDEV_GOING_DOWN, dev); 1393 nb->notifier_call(nb, NETDEV_DOWN, dev); 1394 } 1395 nb->notifier_call(nb, NETDEV_UNREGISTER, dev); 1396 nb->notifier_call(nb, NETDEV_UNREGISTER_BATCH, dev); 1397 } 1398 } 1399 1400 raw_notifier_chain_unregister(&netdev_chain, nb); 1401 goto unlock; 1402 } 1403 EXPORT_SYMBOL(register_netdevice_notifier); 1404 1405 /** 1406 * unregister_netdevice_notifier - unregister a network notifier block 1407 * @nb: notifier 1408 * 1409 * Unregister a notifier previously registered by 1410 * register_netdevice_notifier(). The notifier is unlinked into the 1411 * kernel structures and may then be reused. A negative errno code 1412 * is returned on a failure. 1413 */ 1414 1415 int unregister_netdevice_notifier(struct notifier_block *nb) 1416 { 1417 int err; 1418 1419 rtnl_lock(); 1420 err = raw_notifier_chain_unregister(&netdev_chain, nb); 1421 rtnl_unlock(); 1422 return err; 1423 } 1424 EXPORT_SYMBOL(unregister_netdevice_notifier); 1425 1426 /** 1427 * call_netdevice_notifiers - call all network notifier blocks 1428 * @val: value passed unmodified to notifier function 1429 * @dev: net_device pointer passed unmodified to notifier function 1430 * 1431 * Call all network notifier blocks. Parameters and return value 1432 * are as for raw_notifier_call_chain(). 1433 */ 1434 1435 int call_netdevice_notifiers(unsigned long val, struct net_device *dev) 1436 { 1437 ASSERT_RTNL(); 1438 return raw_notifier_call_chain(&netdev_chain, val, dev); 1439 } 1440 1441 /* When > 0 there are consumers of rx skb time stamps */ 1442 static atomic_t netstamp_needed = ATOMIC_INIT(0); 1443 1444 void net_enable_timestamp(void) 1445 { 1446 atomic_inc(&netstamp_needed); 1447 } 1448 EXPORT_SYMBOL(net_enable_timestamp); 1449 1450 void net_disable_timestamp(void) 1451 { 1452 atomic_dec(&netstamp_needed); 1453 } 1454 EXPORT_SYMBOL(net_disable_timestamp); 1455 1456 static inline void net_timestamp_set(struct sk_buff *skb) 1457 { 1458 if (atomic_read(&netstamp_needed)) 1459 __net_timestamp(skb); 1460 else 1461 skb->tstamp.tv64 = 0; 1462 } 1463 1464 static inline void net_timestamp_check(struct sk_buff *skb) 1465 { 1466 if (!skb->tstamp.tv64 && atomic_read(&netstamp_needed)) 1467 __net_timestamp(skb); 1468 } 1469 1470 /** 1471 * dev_forward_skb - loopback an skb to another netif 1472 * 1473 * @dev: destination network device 1474 * @skb: buffer to forward 1475 * 1476 * return values: 1477 * NET_RX_SUCCESS (no congestion) 1478 * NET_RX_DROP (packet was dropped, but freed) 1479 * 1480 * dev_forward_skb can be used for injecting an skb from the 1481 * start_xmit function of one device into the receive queue 1482 * of another device. 1483 * 1484 * The receiving device may be in another namespace, so 1485 * we have to clear all information in the skb that could 1486 * impact namespace isolation. 1487 */ 1488 int dev_forward_skb(struct net_device *dev, struct sk_buff *skb) 1489 { 1490 skb_orphan(skb); 1491 1492 if (!(dev->flags & IFF_UP) || 1493 (skb->len > (dev->mtu + dev->hard_header_len))) { 1494 kfree_skb(skb); 1495 return NET_RX_DROP; 1496 } 1497 skb_set_dev(skb, dev); 1498 skb->tstamp.tv64 = 0; 1499 skb->pkt_type = PACKET_HOST; 1500 skb->protocol = eth_type_trans(skb, dev); 1501 return netif_rx(skb); 1502 } 1503 EXPORT_SYMBOL_GPL(dev_forward_skb); 1504 1505 /* 1506 * Support routine. Sends outgoing frames to any network 1507 * taps currently in use. 1508 */ 1509 1510 static void dev_queue_xmit_nit(struct sk_buff *skb, struct net_device *dev) 1511 { 1512 struct packet_type *ptype; 1513 1514 #ifdef CONFIG_NET_CLS_ACT 1515 if (!(skb->tstamp.tv64 && (G_TC_FROM(skb->tc_verd) & AT_INGRESS))) 1516 net_timestamp_set(skb); 1517 #else 1518 net_timestamp_set(skb); 1519 #endif 1520 1521 rcu_read_lock(); 1522 list_for_each_entry_rcu(ptype, &ptype_all, list) { 1523 /* Never send packets back to the socket 1524 * they originated from - MvS (miquels@drinkel.ow.org) 1525 */ 1526 if ((ptype->dev == dev || !ptype->dev) && 1527 (ptype->af_packet_priv == NULL || 1528 (struct sock *)ptype->af_packet_priv != skb->sk)) { 1529 struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC); 1530 if (!skb2) 1531 break; 1532 1533 /* skb->nh should be correctly 1534 set by sender, so that the second statement is 1535 just protection against buggy protocols. 1536 */ 1537 skb_reset_mac_header(skb2); 1538 1539 if (skb_network_header(skb2) < skb2->data || 1540 skb2->network_header > skb2->tail) { 1541 if (net_ratelimit()) 1542 printk(KERN_CRIT "protocol %04x is " 1543 "buggy, dev %s\n", 1544 skb2->protocol, dev->name); 1545 skb_reset_network_header(skb2); 1546 } 1547 1548 skb2->transport_header = skb2->network_header; 1549 skb2->pkt_type = PACKET_OUTGOING; 1550 ptype->func(skb2, skb->dev, ptype, skb->dev); 1551 } 1552 } 1553 rcu_read_unlock(); 1554 } 1555 1556 1557 static inline void __netif_reschedule(struct Qdisc *q) 1558 { 1559 struct softnet_data *sd; 1560 unsigned long flags; 1561 1562 local_irq_save(flags); 1563 sd = &__get_cpu_var(softnet_data); 1564 q->next_sched = NULL; 1565 *sd->output_queue_tailp = q; 1566 sd->output_queue_tailp = &q->next_sched; 1567 raise_softirq_irqoff(NET_TX_SOFTIRQ); 1568 local_irq_restore(flags); 1569 } 1570 1571 void __netif_schedule(struct Qdisc *q) 1572 { 1573 if (!test_and_set_bit(__QDISC_STATE_SCHED, &q->state)) 1574 __netif_reschedule(q); 1575 } 1576 EXPORT_SYMBOL(__netif_schedule); 1577 1578 void dev_kfree_skb_irq(struct sk_buff *skb) 1579 { 1580 if (atomic_dec_and_test(&skb->users)) { 1581 struct softnet_data *sd; 1582 unsigned long flags; 1583 1584 local_irq_save(flags); 1585 sd = &__get_cpu_var(softnet_data); 1586 skb->next = sd->completion_queue; 1587 sd->completion_queue = skb; 1588 raise_softirq_irqoff(NET_TX_SOFTIRQ); 1589 local_irq_restore(flags); 1590 } 1591 } 1592 EXPORT_SYMBOL(dev_kfree_skb_irq); 1593 1594 void dev_kfree_skb_any(struct sk_buff *skb) 1595 { 1596 if (in_irq() || irqs_disabled()) 1597 dev_kfree_skb_irq(skb); 1598 else 1599 dev_kfree_skb(skb); 1600 } 1601 EXPORT_SYMBOL(dev_kfree_skb_any); 1602 1603 1604 /** 1605 * netif_device_detach - mark device as removed 1606 * @dev: network device 1607 * 1608 * Mark device as removed from system and therefore no longer available. 1609 */ 1610 void netif_device_detach(struct net_device *dev) 1611 { 1612 if (test_and_clear_bit(__LINK_STATE_PRESENT, &dev->state) && 1613 netif_running(dev)) { 1614 netif_tx_stop_all_queues(dev); 1615 } 1616 } 1617 EXPORT_SYMBOL(netif_device_detach); 1618 1619 /** 1620 * netif_device_attach - mark device as attached 1621 * @dev: network device 1622 * 1623 * Mark device as attached from system and restart if needed. 1624 */ 1625 void netif_device_attach(struct net_device *dev) 1626 { 1627 if (!test_and_set_bit(__LINK_STATE_PRESENT, &dev->state) && 1628 netif_running(dev)) { 1629 netif_tx_wake_all_queues(dev); 1630 __netdev_watchdog_up(dev); 1631 } 1632 } 1633 EXPORT_SYMBOL(netif_device_attach); 1634 1635 static bool can_checksum_protocol(unsigned long features, __be16 protocol) 1636 { 1637 return ((features & NETIF_F_GEN_CSUM) || 1638 ((features & NETIF_F_IP_CSUM) && 1639 protocol == htons(ETH_P_IP)) || 1640 ((features & NETIF_F_IPV6_CSUM) && 1641 protocol == htons(ETH_P_IPV6)) || 1642 ((features & NETIF_F_FCOE_CRC) && 1643 protocol == htons(ETH_P_FCOE))); 1644 } 1645 1646 static bool dev_can_checksum(struct net_device *dev, struct sk_buff *skb) 1647 { 1648 if (can_checksum_protocol(dev->features, skb->protocol)) 1649 return true; 1650 1651 if (skb->protocol == htons(ETH_P_8021Q)) { 1652 struct vlan_ethhdr *veh = (struct vlan_ethhdr *)skb->data; 1653 if (can_checksum_protocol(dev->features & dev->vlan_features, 1654 veh->h_vlan_encapsulated_proto)) 1655 return true; 1656 } 1657 1658 return false; 1659 } 1660 1661 /** 1662 * skb_dev_set -- assign a new device to a buffer 1663 * @skb: buffer for the new device 1664 * @dev: network device 1665 * 1666 * If an skb is owned by a device already, we have to reset 1667 * all data private to the namespace a device belongs to 1668 * before assigning it a new device. 1669 */ 1670 #ifdef CONFIG_NET_NS 1671 void skb_set_dev(struct sk_buff *skb, struct net_device *dev) 1672 { 1673 skb_dst_drop(skb); 1674 if (skb->dev && !net_eq(dev_net(skb->dev), dev_net(dev))) { 1675 secpath_reset(skb); 1676 nf_reset(skb); 1677 skb_init_secmark(skb); 1678 skb->mark = 0; 1679 skb->priority = 0; 1680 skb->nf_trace = 0; 1681 skb->ipvs_property = 0; 1682 #ifdef CONFIG_NET_SCHED 1683 skb->tc_index = 0; 1684 #endif 1685 } 1686 skb->dev = dev; 1687 } 1688 EXPORT_SYMBOL(skb_set_dev); 1689 #endif /* CONFIG_NET_NS */ 1690 1691 /* 1692 * Invalidate hardware checksum when packet is to be mangled, and 1693 * complete checksum manually on outgoing path. 1694 */ 1695 int skb_checksum_help(struct sk_buff *skb) 1696 { 1697 __wsum csum; 1698 int ret = 0, offset; 1699 1700 if (skb->ip_summed == CHECKSUM_COMPLETE) 1701 goto out_set_summed; 1702 1703 if (unlikely(skb_shinfo(skb)->gso_size)) { 1704 /* Let GSO fix up the checksum. */ 1705 goto out_set_summed; 1706 } 1707 1708 offset = skb->csum_start - skb_headroom(skb); 1709 BUG_ON(offset >= skb_headlen(skb)); 1710 csum = skb_checksum(skb, offset, skb->len - offset, 0); 1711 1712 offset += skb->csum_offset; 1713 BUG_ON(offset + sizeof(__sum16) > skb_headlen(skb)); 1714 1715 if (skb_cloned(skb) && 1716 !skb_clone_writable(skb, offset + sizeof(__sum16))) { 1717 ret = pskb_expand_head(skb, 0, 0, GFP_ATOMIC); 1718 if (ret) 1719 goto out; 1720 } 1721 1722 *(__sum16 *)(skb->data + offset) = csum_fold(csum); 1723 out_set_summed: 1724 skb->ip_summed = CHECKSUM_NONE; 1725 out: 1726 return ret; 1727 } 1728 EXPORT_SYMBOL(skb_checksum_help); 1729 1730 /** 1731 * skb_gso_segment - Perform segmentation on skb. 1732 * @skb: buffer to segment 1733 * @features: features for the output path (see dev->features) 1734 * 1735 * This function segments the given skb and returns a list of segments. 1736 * 1737 * It may return NULL if the skb requires no segmentation. This is 1738 * only possible when GSO is used for verifying header integrity. 1739 */ 1740 struct sk_buff *skb_gso_segment(struct sk_buff *skb, int features) 1741 { 1742 struct sk_buff *segs = ERR_PTR(-EPROTONOSUPPORT); 1743 struct packet_type *ptype; 1744 __be16 type = skb->protocol; 1745 int err; 1746 1747 skb_reset_mac_header(skb); 1748 skb->mac_len = skb->network_header - skb->mac_header; 1749 __skb_pull(skb, skb->mac_len); 1750 1751 if (unlikely(skb->ip_summed != CHECKSUM_PARTIAL)) { 1752 struct net_device *dev = skb->dev; 1753 struct ethtool_drvinfo info = {}; 1754 1755 if (dev && dev->ethtool_ops && dev->ethtool_ops->get_drvinfo) 1756 dev->ethtool_ops->get_drvinfo(dev, &info); 1757 1758 WARN(1, "%s: caps=(0x%lx, 0x%lx) len=%d data_len=%d " 1759 "ip_summed=%d", 1760 info.driver, dev ? dev->features : 0L, 1761 skb->sk ? skb->sk->sk_route_caps : 0L, 1762 skb->len, skb->data_len, skb->ip_summed); 1763 1764 if (skb_header_cloned(skb) && 1765 (err = pskb_expand_head(skb, 0, 0, GFP_ATOMIC))) 1766 return ERR_PTR(err); 1767 } 1768 1769 rcu_read_lock(); 1770 list_for_each_entry_rcu(ptype, 1771 &ptype_base[ntohs(type) & PTYPE_HASH_MASK], list) { 1772 if (ptype->type == type && !ptype->dev && ptype->gso_segment) { 1773 if (unlikely(skb->ip_summed != CHECKSUM_PARTIAL)) { 1774 err = ptype->gso_send_check(skb); 1775 segs = ERR_PTR(err); 1776 if (err || skb_gso_ok(skb, features)) 1777 break; 1778 __skb_push(skb, (skb->data - 1779 skb_network_header(skb))); 1780 } 1781 segs = ptype->gso_segment(skb, features); 1782 break; 1783 } 1784 } 1785 rcu_read_unlock(); 1786 1787 __skb_push(skb, skb->data - skb_mac_header(skb)); 1788 1789 return segs; 1790 } 1791 EXPORT_SYMBOL(skb_gso_segment); 1792 1793 /* Take action when hardware reception checksum errors are detected. */ 1794 #ifdef CONFIG_BUG 1795 void netdev_rx_csum_fault(struct net_device *dev) 1796 { 1797 if (net_ratelimit()) { 1798 printk(KERN_ERR "%s: hw csum failure.\n", 1799 dev ? dev->name : "<unknown>"); 1800 dump_stack(); 1801 } 1802 } 1803 EXPORT_SYMBOL(netdev_rx_csum_fault); 1804 #endif 1805 1806 /* Actually, we should eliminate this check as soon as we know, that: 1807 * 1. IOMMU is present and allows to map all the memory. 1808 * 2. No high memory really exists on this machine. 1809 */ 1810 1811 static int illegal_highdma(struct net_device *dev, struct sk_buff *skb) 1812 { 1813 #ifdef CONFIG_HIGHMEM 1814 int i; 1815 if (!(dev->features & NETIF_F_HIGHDMA)) { 1816 for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) 1817 if (PageHighMem(skb_shinfo(skb)->frags[i].page)) 1818 return 1; 1819 } 1820 1821 if (PCI_DMA_BUS_IS_PHYS) { 1822 struct device *pdev = dev->dev.parent; 1823 1824 if (!pdev) 1825 return 0; 1826 for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) { 1827 dma_addr_t addr = page_to_phys(skb_shinfo(skb)->frags[i].page); 1828 if (!pdev->dma_mask || addr + PAGE_SIZE - 1 > *pdev->dma_mask) 1829 return 1; 1830 } 1831 } 1832 #endif 1833 return 0; 1834 } 1835 1836 struct dev_gso_cb { 1837 void (*destructor)(struct sk_buff *skb); 1838 }; 1839 1840 #define DEV_GSO_CB(skb) ((struct dev_gso_cb *)(skb)->cb) 1841 1842 static void dev_gso_skb_destructor(struct sk_buff *skb) 1843 { 1844 struct dev_gso_cb *cb; 1845 1846 do { 1847 struct sk_buff *nskb = skb->next; 1848 1849 skb->next = nskb->next; 1850 nskb->next = NULL; 1851 kfree_skb(nskb); 1852 } while (skb->next); 1853 1854 cb = DEV_GSO_CB(skb); 1855 if (cb->destructor) 1856 cb->destructor(skb); 1857 } 1858 1859 /** 1860 * dev_gso_segment - Perform emulated hardware segmentation on skb. 1861 * @skb: buffer to segment 1862 * 1863 * This function segments the given skb and stores the list of segments 1864 * in skb->next. 1865 */ 1866 static int dev_gso_segment(struct sk_buff *skb) 1867 { 1868 struct net_device *dev = skb->dev; 1869 struct sk_buff *segs; 1870 int features = dev->features & ~(illegal_highdma(dev, skb) ? 1871 NETIF_F_SG : 0); 1872 1873 segs = skb_gso_segment(skb, features); 1874 1875 /* Verifying header integrity only. */ 1876 if (!segs) 1877 return 0; 1878 1879 if (IS_ERR(segs)) 1880 return PTR_ERR(segs); 1881 1882 skb->next = segs; 1883 DEV_GSO_CB(skb)->destructor = skb->destructor; 1884 skb->destructor = dev_gso_skb_destructor; 1885 1886 return 0; 1887 } 1888 1889 /* 1890 * Try to orphan skb early, right before transmission by the device. 1891 * We cannot orphan skb if tx timestamp is requested, since 1892 * drivers need to call skb_tstamp_tx() to send the timestamp. 1893 */ 1894 static inline void skb_orphan_try(struct sk_buff *skb) 1895 { 1896 if (!skb_tx(skb)->flags) 1897 skb_orphan(skb); 1898 } 1899 1900 int dev_hard_start_xmit(struct sk_buff *skb, struct net_device *dev, 1901 struct netdev_queue *txq) 1902 { 1903 const struct net_device_ops *ops = dev->netdev_ops; 1904 int rc = NETDEV_TX_OK; 1905 1906 if (likely(!skb->next)) { 1907 if (!list_empty(&ptype_all)) 1908 dev_queue_xmit_nit(skb, dev); 1909 1910 /* 1911 * If device doesnt need skb->dst, release it right now while 1912 * its hot in this cpu cache 1913 */ 1914 if (dev->priv_flags & IFF_XMIT_DST_RELEASE) 1915 skb_dst_drop(skb); 1916 1917 skb_orphan_try(skb); 1918 1919 if (netif_needs_gso(dev, skb)) { 1920 if (unlikely(dev_gso_segment(skb))) 1921 goto out_kfree_skb; 1922 if (skb->next) 1923 goto gso; 1924 } 1925 1926 rc = ops->ndo_start_xmit(skb, dev); 1927 if (rc == NETDEV_TX_OK) 1928 txq_trans_update(txq); 1929 return rc; 1930 } 1931 1932 gso: 1933 do { 1934 struct sk_buff *nskb = skb->next; 1935 1936 skb->next = nskb->next; 1937 nskb->next = NULL; 1938 1939 /* 1940 * If device doesnt need nskb->dst, release it right now while 1941 * its hot in this cpu cache 1942 */ 1943 if (dev->priv_flags & IFF_XMIT_DST_RELEASE) 1944 skb_dst_drop(nskb); 1945 1946 rc = ops->ndo_start_xmit(nskb, dev); 1947 if (unlikely(rc != NETDEV_TX_OK)) { 1948 if (rc & ~NETDEV_TX_MASK) 1949 goto out_kfree_gso_skb; 1950 nskb->next = skb->next; 1951 skb->next = nskb; 1952 return rc; 1953 } 1954 txq_trans_update(txq); 1955 if (unlikely(netif_tx_queue_stopped(txq) && skb->next)) 1956 return NETDEV_TX_BUSY; 1957 } while (skb->next); 1958 1959 out_kfree_gso_skb: 1960 if (likely(skb->next == NULL)) 1961 skb->destructor = DEV_GSO_CB(skb)->destructor; 1962 out_kfree_skb: 1963 kfree_skb(skb); 1964 return rc; 1965 } 1966 1967 static u32 hashrnd __read_mostly; 1968 1969 u16 skb_tx_hash(const struct net_device *dev, const struct sk_buff *skb) 1970 { 1971 u32 hash; 1972 1973 if (skb_rx_queue_recorded(skb)) { 1974 hash = skb_get_rx_queue(skb); 1975 while (unlikely(hash >= dev->real_num_tx_queues)) 1976 hash -= dev->real_num_tx_queues; 1977 return hash; 1978 } 1979 1980 if (skb->sk && skb->sk->sk_hash) 1981 hash = skb->sk->sk_hash; 1982 else 1983 hash = (__force u16) skb->protocol; 1984 1985 hash = jhash_1word(hash, hashrnd); 1986 1987 return (u16) (((u64) hash * dev->real_num_tx_queues) >> 32); 1988 } 1989 EXPORT_SYMBOL(skb_tx_hash); 1990 1991 static inline u16 dev_cap_txqueue(struct net_device *dev, u16 queue_index) 1992 { 1993 if (unlikely(queue_index >= dev->real_num_tx_queues)) { 1994 if (net_ratelimit()) { 1995 pr_warning("%s selects TX queue %d, but " 1996 "real number of TX queues is %d\n", 1997 dev->name, queue_index, dev->real_num_tx_queues); 1998 } 1999 return 0; 2000 } 2001 return queue_index; 2002 } 2003 2004 static struct netdev_queue *dev_pick_tx(struct net_device *dev, 2005 struct sk_buff *skb) 2006 { 2007 u16 queue_index; 2008 struct sock *sk = skb->sk; 2009 2010 if (sk_tx_queue_recorded(sk)) { 2011 queue_index = sk_tx_queue_get(sk); 2012 } else { 2013 const struct net_device_ops *ops = dev->netdev_ops; 2014 2015 if (ops->ndo_select_queue) { 2016 queue_index = ops->ndo_select_queue(dev, skb); 2017 queue_index = dev_cap_txqueue(dev, queue_index); 2018 } else { 2019 queue_index = 0; 2020 if (dev->real_num_tx_queues > 1) 2021 queue_index = skb_tx_hash(dev, skb); 2022 2023 if (sk) { 2024 struct dst_entry *dst = rcu_dereference_check(sk->sk_dst_cache, 1); 2025 2026 if (dst && skb_dst(skb) == dst) 2027 sk_tx_queue_set(sk, queue_index); 2028 } 2029 } 2030 } 2031 2032 skb_set_queue_mapping(skb, queue_index); 2033 return netdev_get_tx_queue(dev, queue_index); 2034 } 2035 2036 static inline int __dev_xmit_skb(struct sk_buff *skb, struct Qdisc *q, 2037 struct net_device *dev, 2038 struct netdev_queue *txq) 2039 { 2040 spinlock_t *root_lock = qdisc_lock(q); 2041 int rc; 2042 2043 spin_lock(root_lock); 2044 if (unlikely(test_bit(__QDISC_STATE_DEACTIVATED, &q->state))) { 2045 kfree_skb(skb); 2046 rc = NET_XMIT_DROP; 2047 } else if ((q->flags & TCQ_F_CAN_BYPASS) && !qdisc_qlen(q) && 2048 !test_and_set_bit(__QDISC_STATE_RUNNING, &q->state)) { 2049 /* 2050 * This is a work-conserving queue; there are no old skbs 2051 * waiting to be sent out; and the qdisc is not running - 2052 * xmit the skb directly. 2053 */ 2054 if (!(dev->priv_flags & IFF_XMIT_DST_RELEASE)) 2055 skb_dst_force(skb); 2056 __qdisc_update_bstats(q, skb->len); 2057 if (sch_direct_xmit(skb, q, dev, txq, root_lock)) 2058 __qdisc_run(q); 2059 else 2060 clear_bit(__QDISC_STATE_RUNNING, &q->state); 2061 2062 rc = NET_XMIT_SUCCESS; 2063 } else { 2064 skb_dst_force(skb); 2065 rc = qdisc_enqueue_root(skb, q); 2066 qdisc_run(q); 2067 } 2068 spin_unlock(root_lock); 2069 2070 return rc; 2071 } 2072 2073 /* 2074 * Returns true if either: 2075 * 1. skb has frag_list and the device doesn't support FRAGLIST, or 2076 * 2. skb is fragmented and the device does not support SG, or if 2077 * at least one of fragments is in highmem and device does not 2078 * support DMA from it. 2079 */ 2080 static inline int skb_needs_linearize(struct sk_buff *skb, 2081 struct net_device *dev) 2082 { 2083 return (skb_has_frags(skb) && !(dev->features & NETIF_F_FRAGLIST)) || 2084 (skb_shinfo(skb)->nr_frags && (!(dev->features & NETIF_F_SG) || 2085 illegal_highdma(dev, skb))); 2086 } 2087 2088 /** 2089 * dev_queue_xmit - transmit a buffer 2090 * @skb: buffer to transmit 2091 * 2092 * Queue a buffer for transmission to a network device. The caller must 2093 * have set the device and priority and built the buffer before calling 2094 * this function. The function can be called from an interrupt. 2095 * 2096 * A negative errno code is returned on a failure. A success does not 2097 * guarantee the frame will be transmitted as it may be dropped due 2098 * to congestion or traffic shaping. 2099 * 2100 * ----------------------------------------------------------------------------------- 2101 * I notice this method can also return errors from the queue disciplines, 2102 * including NET_XMIT_DROP, which is a positive value. So, errors can also 2103 * be positive. 2104 * 2105 * Regardless of the return value, the skb is consumed, so it is currently 2106 * difficult to retry a send to this method. (You can bump the ref count 2107 * before sending to hold a reference for retry if you are careful.) 2108 * 2109 * When calling this method, interrupts MUST be enabled. This is because 2110 * the BH enable code must have IRQs enabled so that it will not deadlock. 2111 * --BLG 2112 */ 2113 int dev_queue_xmit(struct sk_buff *skb) 2114 { 2115 struct net_device *dev = skb->dev; 2116 struct netdev_queue *txq; 2117 struct Qdisc *q; 2118 int rc = -ENOMEM; 2119 2120 /* GSO will handle the following emulations directly. */ 2121 if (netif_needs_gso(dev, skb)) 2122 goto gso; 2123 2124 /* Convert a paged skb to linear, if required */ 2125 if (skb_needs_linearize(skb, dev) && __skb_linearize(skb)) 2126 goto out_kfree_skb; 2127 2128 /* If packet is not checksummed and device does not support 2129 * checksumming for this protocol, complete checksumming here. 2130 */ 2131 if (skb->ip_summed == CHECKSUM_PARTIAL) { 2132 skb_set_transport_header(skb, skb->csum_start - 2133 skb_headroom(skb)); 2134 if (!dev_can_checksum(dev, skb) && skb_checksum_help(skb)) 2135 goto out_kfree_skb; 2136 } 2137 2138 gso: 2139 /* Disable soft irqs for various locks below. Also 2140 * stops preemption for RCU. 2141 */ 2142 rcu_read_lock_bh(); 2143 2144 txq = dev_pick_tx(dev, skb); 2145 q = rcu_dereference_bh(txq->qdisc); 2146 2147 #ifdef CONFIG_NET_CLS_ACT 2148 skb->tc_verd = SET_TC_AT(skb->tc_verd, AT_EGRESS); 2149 #endif 2150 if (q->enqueue) { 2151 rc = __dev_xmit_skb(skb, q, dev, txq); 2152 goto out; 2153 } 2154 2155 /* The device has no queue. Common case for software devices: 2156 loopback, all the sorts of tunnels... 2157 2158 Really, it is unlikely that netif_tx_lock protection is necessary 2159 here. (f.e. loopback and IP tunnels are clean ignoring statistics 2160 counters.) 2161 However, it is possible, that they rely on protection 2162 made by us here. 2163 2164 Check this and shot the lock. It is not prone from deadlocks. 2165 Either shot noqueue qdisc, it is even simpler 8) 2166 */ 2167 if (dev->flags & IFF_UP) { 2168 int cpu = smp_processor_id(); /* ok because BHs are off */ 2169 2170 if (txq->xmit_lock_owner != cpu) { 2171 2172 HARD_TX_LOCK(dev, txq, cpu); 2173 2174 if (!netif_tx_queue_stopped(txq)) { 2175 rc = dev_hard_start_xmit(skb, dev, txq); 2176 if (dev_xmit_complete(rc)) { 2177 HARD_TX_UNLOCK(dev, txq); 2178 goto out; 2179 } 2180 } 2181 HARD_TX_UNLOCK(dev, txq); 2182 if (net_ratelimit()) 2183 printk(KERN_CRIT "Virtual device %s asks to " 2184 "queue packet!\n", dev->name); 2185 } else { 2186 /* Recursion is detected! It is possible, 2187 * unfortunately */ 2188 if (net_ratelimit()) 2189 printk(KERN_CRIT "Dead loop on virtual device " 2190 "%s, fix it urgently!\n", dev->name); 2191 } 2192 } 2193 2194 rc = -ENETDOWN; 2195 rcu_read_unlock_bh(); 2196 2197 out_kfree_skb: 2198 kfree_skb(skb); 2199 return rc; 2200 out: 2201 rcu_read_unlock_bh(); 2202 return rc; 2203 } 2204 EXPORT_SYMBOL(dev_queue_xmit); 2205 2206 2207 /*======================================================================= 2208 Receiver routines 2209 =======================================================================*/ 2210 2211 int netdev_max_backlog __read_mostly = 1000; 2212 int netdev_tstamp_prequeue __read_mostly = 1; 2213 int netdev_budget __read_mostly = 300; 2214 int weight_p __read_mostly = 64; /* old backlog weight */ 2215 2216 /* Called with irq disabled */ 2217 static inline void ____napi_schedule(struct softnet_data *sd, 2218 struct napi_struct *napi) 2219 { 2220 list_add_tail(&napi->poll_list, &sd->poll_list); 2221 __raise_softirq_irqoff(NET_RX_SOFTIRQ); 2222 } 2223 2224 #ifdef CONFIG_RPS 2225 2226 /* One global table that all flow-based protocols share. */ 2227 struct rps_sock_flow_table *rps_sock_flow_table __read_mostly; 2228 EXPORT_SYMBOL(rps_sock_flow_table); 2229 2230 /* 2231 * get_rps_cpu is called from netif_receive_skb and returns the target 2232 * CPU from the RPS map of the receiving queue for a given skb. 2233 * rcu_read_lock must be held on entry. 2234 */ 2235 static int get_rps_cpu(struct net_device *dev, struct sk_buff *skb, 2236 struct rps_dev_flow **rflowp) 2237 { 2238 struct ipv6hdr *ip6; 2239 struct iphdr *ip; 2240 struct netdev_rx_queue *rxqueue; 2241 struct rps_map *map; 2242 struct rps_dev_flow_table *flow_table; 2243 struct rps_sock_flow_table *sock_flow_table; 2244 int cpu = -1; 2245 u8 ip_proto; 2246 u16 tcpu; 2247 u32 addr1, addr2, ihl; 2248 union { 2249 u32 v32; 2250 u16 v16[2]; 2251 } ports; 2252 2253 if (skb_rx_queue_recorded(skb)) { 2254 u16 index = skb_get_rx_queue(skb); 2255 if (unlikely(index >= dev->num_rx_queues)) { 2256 WARN_ONCE(dev->num_rx_queues > 1, "%s received packet " 2257 "on queue %u, but number of RX queues is %u\n", 2258 dev->name, index, dev->num_rx_queues); 2259 goto done; 2260 } 2261 rxqueue = dev->_rx + index; 2262 } else 2263 rxqueue = dev->_rx; 2264 2265 if (!rxqueue->rps_map && !rxqueue->rps_flow_table) 2266 goto done; 2267 2268 if (skb->rxhash) 2269 goto got_hash; /* Skip hash computation on packet header */ 2270 2271 switch (skb->protocol) { 2272 case __constant_htons(ETH_P_IP): 2273 if (!pskb_may_pull(skb, sizeof(*ip))) 2274 goto done; 2275 2276 ip = (struct iphdr *) skb->data; 2277 ip_proto = ip->protocol; 2278 addr1 = (__force u32) ip->saddr; 2279 addr2 = (__force u32) ip->daddr; 2280 ihl = ip->ihl; 2281 break; 2282 case __constant_htons(ETH_P_IPV6): 2283 if (!pskb_may_pull(skb, sizeof(*ip6))) 2284 goto done; 2285 2286 ip6 = (struct ipv6hdr *) skb->data; 2287 ip_proto = ip6->nexthdr; 2288 addr1 = (__force u32) ip6->saddr.s6_addr32[3]; 2289 addr2 = (__force u32) ip6->daddr.s6_addr32[3]; 2290 ihl = (40 >> 2); 2291 break; 2292 default: 2293 goto done; 2294 } 2295 switch (ip_proto) { 2296 case IPPROTO_TCP: 2297 case IPPROTO_UDP: 2298 case IPPROTO_DCCP: 2299 case IPPROTO_ESP: 2300 case IPPROTO_AH: 2301 case IPPROTO_SCTP: 2302 case IPPROTO_UDPLITE: 2303 if (pskb_may_pull(skb, (ihl * 4) + 4)) { 2304 ports.v32 = * (__force u32 *) (skb->data + (ihl * 4)); 2305 if (ports.v16[1] < ports.v16[0]) 2306 swap(ports.v16[0], ports.v16[1]); 2307 break; 2308 } 2309 default: 2310 ports.v32 = 0; 2311 break; 2312 } 2313 2314 /* get a consistent hash (same value on both flow directions) */ 2315 if (addr2 < addr1) 2316 swap(addr1, addr2); 2317 skb->rxhash = jhash_3words(addr1, addr2, ports.v32, hashrnd); 2318 if (!skb->rxhash) 2319 skb->rxhash = 1; 2320 2321 got_hash: 2322 flow_table = rcu_dereference(rxqueue->rps_flow_table); 2323 sock_flow_table = rcu_dereference(rps_sock_flow_table); 2324 if (flow_table && sock_flow_table) { 2325 u16 next_cpu; 2326 struct rps_dev_flow *rflow; 2327 2328 rflow = &flow_table->flows[skb->rxhash & flow_table->mask]; 2329 tcpu = rflow->cpu; 2330 2331 next_cpu = sock_flow_table->ents[skb->rxhash & 2332 sock_flow_table->mask]; 2333 2334 /* 2335 * If the desired CPU (where last recvmsg was done) is 2336 * different from current CPU (one in the rx-queue flow 2337 * table entry), switch if one of the following holds: 2338 * - Current CPU is unset (equal to RPS_NO_CPU). 2339 * - Current CPU is offline. 2340 * - The current CPU's queue tail has advanced beyond the 2341 * last packet that was enqueued using this table entry. 2342 * This guarantees that all previous packets for the flow 2343 * have been dequeued, thus preserving in order delivery. 2344 */ 2345 if (unlikely(tcpu != next_cpu) && 2346 (tcpu == RPS_NO_CPU || !cpu_online(tcpu) || 2347 ((int)(per_cpu(softnet_data, tcpu).input_queue_head - 2348 rflow->last_qtail)) >= 0)) { 2349 tcpu = rflow->cpu = next_cpu; 2350 if (tcpu != RPS_NO_CPU) 2351 rflow->last_qtail = per_cpu(softnet_data, 2352 tcpu).input_queue_head; 2353 } 2354 if (tcpu != RPS_NO_CPU && cpu_online(tcpu)) { 2355 *rflowp = rflow; 2356 cpu = tcpu; 2357 goto done; 2358 } 2359 } 2360 2361 map = rcu_dereference(rxqueue->rps_map); 2362 if (map) { 2363 tcpu = map->cpus[((u64) skb->rxhash * map->len) >> 32]; 2364 2365 if (cpu_online(tcpu)) { 2366 cpu = tcpu; 2367 goto done; 2368 } 2369 } 2370 2371 done: 2372 return cpu; 2373 } 2374 2375 /* Called from hardirq (IPI) context */ 2376 static void rps_trigger_softirq(void *data) 2377 { 2378 struct softnet_data *sd = data; 2379 2380 ____napi_schedule(sd, &sd->backlog); 2381 sd->received_rps++; 2382 } 2383 2384 #endif /* CONFIG_RPS */ 2385 2386 /* 2387 * Check if this softnet_data structure is another cpu one 2388 * If yes, queue it to our IPI list and return 1 2389 * If no, return 0 2390 */ 2391 static int rps_ipi_queued(struct softnet_data *sd) 2392 { 2393 #ifdef CONFIG_RPS 2394 struct softnet_data *mysd = &__get_cpu_var(softnet_data); 2395 2396 if (sd != mysd) { 2397 sd->rps_ipi_next = mysd->rps_ipi_list; 2398 mysd->rps_ipi_list = sd; 2399 2400 __raise_softirq_irqoff(NET_RX_SOFTIRQ); 2401 return 1; 2402 } 2403 #endif /* CONFIG_RPS */ 2404 return 0; 2405 } 2406 2407 /* 2408 * enqueue_to_backlog is called to queue an skb to a per CPU backlog 2409 * queue (may be a remote CPU queue). 2410 */ 2411 static int enqueue_to_backlog(struct sk_buff *skb, int cpu, 2412 unsigned int *qtail) 2413 { 2414 struct softnet_data *sd; 2415 unsigned long flags; 2416 2417 sd = &per_cpu(softnet_data, cpu); 2418 2419 local_irq_save(flags); 2420 2421 rps_lock(sd); 2422 if (skb_queue_len(&sd->input_pkt_queue) <= netdev_max_backlog) { 2423 if (skb_queue_len(&sd->input_pkt_queue)) { 2424 enqueue: 2425 __skb_queue_tail(&sd->input_pkt_queue, skb); 2426 input_queue_tail_incr_save(sd, qtail); 2427 rps_unlock(sd); 2428 local_irq_restore(flags); 2429 return NET_RX_SUCCESS; 2430 } 2431 2432 /* Schedule NAPI for backlog device 2433 * We can use non atomic operation since we own the queue lock 2434 */ 2435 if (!__test_and_set_bit(NAPI_STATE_SCHED, &sd->backlog.state)) { 2436 if (!rps_ipi_queued(sd)) 2437 ____napi_schedule(sd, &sd->backlog); 2438 } 2439 goto enqueue; 2440 } 2441 2442 sd->dropped++; 2443 rps_unlock(sd); 2444 2445 local_irq_restore(flags); 2446 2447 kfree_skb(skb); 2448 return NET_RX_DROP; 2449 } 2450 2451 /** 2452 * netif_rx - post buffer to the network code 2453 * @skb: buffer to post 2454 * 2455 * This function receives a packet from a device driver and queues it for 2456 * the upper (protocol) levels to process. It always succeeds. The buffer 2457 * may be dropped during processing for congestion control or by the 2458 * protocol layers. 2459 * 2460 * return values: 2461 * NET_RX_SUCCESS (no congestion) 2462 * NET_RX_DROP (packet was dropped) 2463 * 2464 */ 2465 2466 int netif_rx(struct sk_buff *skb) 2467 { 2468 int ret; 2469 2470 /* if netpoll wants it, pretend we never saw it */ 2471 if (netpoll_rx(skb)) 2472 return NET_RX_DROP; 2473 2474 if (netdev_tstamp_prequeue) 2475 net_timestamp_check(skb); 2476 2477 #ifdef CONFIG_RPS 2478 { 2479 struct rps_dev_flow voidflow, *rflow = &voidflow; 2480 int cpu; 2481 2482 rcu_read_lock(); 2483 2484 cpu = get_rps_cpu(skb->dev, skb, &rflow); 2485 if (cpu < 0) 2486 cpu = smp_processor_id(); 2487 2488 ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail); 2489 2490 rcu_read_unlock(); 2491 } 2492 #else 2493 { 2494 unsigned int qtail; 2495 ret = enqueue_to_backlog(skb, get_cpu(), &qtail); 2496 put_cpu(); 2497 } 2498 #endif 2499 return ret; 2500 } 2501 EXPORT_SYMBOL(netif_rx); 2502 2503 int netif_rx_ni(struct sk_buff *skb) 2504 { 2505 int err; 2506 2507 preempt_disable(); 2508 err = netif_rx(skb); 2509 if (local_softirq_pending()) 2510 do_softirq(); 2511 preempt_enable(); 2512 2513 return err; 2514 } 2515 EXPORT_SYMBOL(netif_rx_ni); 2516 2517 static void net_tx_action(struct softirq_action *h) 2518 { 2519 struct softnet_data *sd = &__get_cpu_var(softnet_data); 2520 2521 if (sd->completion_queue) { 2522 struct sk_buff *clist; 2523 2524 local_irq_disable(); 2525 clist = sd->completion_queue; 2526 sd->completion_queue = NULL; 2527 local_irq_enable(); 2528 2529 while (clist) { 2530 struct sk_buff *skb = clist; 2531 clist = clist->next; 2532 2533 WARN_ON(atomic_read(&skb->users)); 2534 __kfree_skb(skb); 2535 } 2536 } 2537 2538 if (sd->output_queue) { 2539 struct Qdisc *head; 2540 2541 local_irq_disable(); 2542 head = sd->output_queue; 2543 sd->output_queue = NULL; 2544 sd->output_queue_tailp = &sd->output_queue; 2545 local_irq_enable(); 2546 2547 while (head) { 2548 struct Qdisc *q = head; 2549 spinlock_t *root_lock; 2550 2551 head = head->next_sched; 2552 2553 root_lock = qdisc_lock(q); 2554 if (spin_trylock(root_lock)) { 2555 smp_mb__before_clear_bit(); 2556 clear_bit(__QDISC_STATE_SCHED, 2557 &q->state); 2558 qdisc_run(q); 2559 spin_unlock(root_lock); 2560 } else { 2561 if (!test_bit(__QDISC_STATE_DEACTIVATED, 2562 &q->state)) { 2563 __netif_reschedule(q); 2564 } else { 2565 smp_mb__before_clear_bit(); 2566 clear_bit(__QDISC_STATE_SCHED, 2567 &q->state); 2568 } 2569 } 2570 } 2571 } 2572 } 2573 2574 static inline int deliver_skb(struct sk_buff *skb, 2575 struct packet_type *pt_prev, 2576 struct net_device *orig_dev) 2577 { 2578 atomic_inc(&skb->users); 2579 return pt_prev->func(skb, skb->dev, pt_prev, orig_dev); 2580 } 2581 2582 #if defined(CONFIG_BRIDGE) || defined (CONFIG_BRIDGE_MODULE) 2583 2584 #if defined(CONFIG_ATM_LANE) || defined(CONFIG_ATM_LANE_MODULE) 2585 /* This hook is defined here for ATM LANE */ 2586 int (*br_fdb_test_addr_hook)(struct net_device *dev, 2587 unsigned char *addr) __read_mostly; 2588 EXPORT_SYMBOL_GPL(br_fdb_test_addr_hook); 2589 #endif 2590 2591 /* 2592 * If bridge module is loaded call bridging hook. 2593 * returns NULL if packet was consumed. 2594 */ 2595 struct sk_buff *(*br_handle_frame_hook)(struct net_bridge_port *p, 2596 struct sk_buff *skb) __read_mostly; 2597 EXPORT_SYMBOL_GPL(br_handle_frame_hook); 2598 2599 static inline struct sk_buff *handle_bridge(struct sk_buff *skb, 2600 struct packet_type **pt_prev, int *ret, 2601 struct net_device *orig_dev) 2602 { 2603 struct net_bridge_port *port; 2604 2605 if (skb->pkt_type == PACKET_LOOPBACK || 2606 (port = rcu_dereference(skb->dev->br_port)) == NULL) 2607 return skb; 2608 2609 if (*pt_prev) { 2610 *ret = deliver_skb(skb, *pt_prev, orig_dev); 2611 *pt_prev = NULL; 2612 } 2613 2614 return br_handle_frame_hook(port, skb); 2615 } 2616 #else 2617 #define handle_bridge(skb, pt_prev, ret, orig_dev) (skb) 2618 #endif 2619 2620 #if defined(CONFIG_MACVLAN) || defined(CONFIG_MACVLAN_MODULE) 2621 struct sk_buff *(*macvlan_handle_frame_hook)(struct macvlan_port *p, 2622 struct sk_buff *skb) __read_mostly; 2623 EXPORT_SYMBOL_GPL(macvlan_handle_frame_hook); 2624 2625 static inline struct sk_buff *handle_macvlan(struct sk_buff *skb, 2626 struct packet_type **pt_prev, 2627 int *ret, 2628 struct net_device *orig_dev) 2629 { 2630 struct macvlan_port *port; 2631 2632 port = rcu_dereference(skb->dev->macvlan_port); 2633 if (!port) 2634 return skb; 2635 2636 if (*pt_prev) { 2637 *ret = deliver_skb(skb, *pt_prev, orig_dev); 2638 *pt_prev = NULL; 2639 } 2640 return macvlan_handle_frame_hook(port, skb); 2641 } 2642 #else 2643 #define handle_macvlan(skb, pt_prev, ret, orig_dev) (skb) 2644 #endif 2645 2646 #ifdef CONFIG_NET_CLS_ACT 2647 /* TODO: Maybe we should just force sch_ingress to be compiled in 2648 * when CONFIG_NET_CLS_ACT is? otherwise some useless instructions 2649 * a compare and 2 stores extra right now if we dont have it on 2650 * but have CONFIG_NET_CLS_ACT 2651 * NOTE: This doesnt stop any functionality; if you dont have 2652 * the ingress scheduler, you just cant add policies on ingress. 2653 * 2654 */ 2655 static int ing_filter(struct sk_buff *skb) 2656 { 2657 struct net_device *dev = skb->dev; 2658 u32 ttl = G_TC_RTTL(skb->tc_verd); 2659 struct netdev_queue *rxq; 2660 int result = TC_ACT_OK; 2661 struct Qdisc *q; 2662 2663 if (MAX_RED_LOOP < ttl++) { 2664 printk(KERN_WARNING 2665 "Redir loop detected Dropping packet (%d->%d)\n", 2666 skb->skb_iif, dev->ifindex); 2667 return TC_ACT_SHOT; 2668 } 2669 2670 skb->tc_verd = SET_TC_RTTL(skb->tc_verd, ttl); 2671 skb->tc_verd = SET_TC_AT(skb->tc_verd, AT_INGRESS); 2672 2673 rxq = &dev->rx_queue; 2674 2675 q = rxq->qdisc; 2676 if (q != &noop_qdisc) { 2677 spin_lock(qdisc_lock(q)); 2678 if (likely(!test_bit(__QDISC_STATE_DEACTIVATED, &q->state))) 2679 result = qdisc_enqueue_root(skb, q); 2680 spin_unlock(qdisc_lock(q)); 2681 } 2682 2683 return result; 2684 } 2685 2686 static inline struct sk_buff *handle_ing(struct sk_buff *skb, 2687 struct packet_type **pt_prev, 2688 int *ret, struct net_device *orig_dev) 2689 { 2690 if (skb->dev->rx_queue.qdisc == &noop_qdisc) 2691 goto out; 2692 2693 if (*pt_prev) { 2694 *ret = deliver_skb(skb, *pt_prev, orig_dev); 2695 *pt_prev = NULL; 2696 } else { 2697 /* Huh? Why does turning on AF_PACKET affect this? */ 2698 skb->tc_verd = SET_TC_OK2MUNGE(skb->tc_verd); 2699 } 2700 2701 switch (ing_filter(skb)) { 2702 case TC_ACT_SHOT: 2703 case TC_ACT_STOLEN: 2704 kfree_skb(skb); 2705 return NULL; 2706 } 2707 2708 out: 2709 skb->tc_verd = 0; 2710 return skb; 2711 } 2712 #endif 2713 2714 /* 2715 * netif_nit_deliver - deliver received packets to network taps 2716 * @skb: buffer 2717 * 2718 * This function is used to deliver incoming packets to network 2719 * taps. It should be used when the normal netif_receive_skb path 2720 * is bypassed, for example because of VLAN acceleration. 2721 */ 2722 void netif_nit_deliver(struct sk_buff *skb) 2723 { 2724 struct packet_type *ptype; 2725 2726 if (list_empty(&ptype_all)) 2727 return; 2728 2729 skb_reset_network_header(skb); 2730 skb_reset_transport_header(skb); 2731 skb->mac_len = skb->network_header - skb->mac_header; 2732 2733 rcu_read_lock(); 2734 list_for_each_entry_rcu(ptype, &ptype_all, list) { 2735 if (!ptype->dev || ptype->dev == skb->dev) 2736 deliver_skb(skb, ptype, skb->dev); 2737 } 2738 rcu_read_unlock(); 2739 } 2740 2741 static inline void skb_bond_set_mac_by_master(struct sk_buff *skb, 2742 struct net_device *master) 2743 { 2744 if (skb->pkt_type == PACKET_HOST) { 2745 u16 *dest = (u16 *) eth_hdr(skb)->h_dest; 2746 2747 memcpy(dest, master->dev_addr, ETH_ALEN); 2748 } 2749 } 2750 2751 /* On bonding slaves other than the currently active slave, suppress 2752 * duplicates except for 802.3ad ETH_P_SLOW, alb non-mcast/bcast, and 2753 * ARP on active-backup slaves with arp_validate enabled. 2754 */ 2755 int __skb_bond_should_drop(struct sk_buff *skb, struct net_device *master) 2756 { 2757 struct net_device *dev = skb->dev; 2758 2759 if (master->priv_flags & IFF_MASTER_ARPMON) 2760 dev->last_rx = jiffies; 2761 2762 if ((master->priv_flags & IFF_MASTER_ALB) && master->br_port) { 2763 /* Do address unmangle. The local destination address 2764 * will be always the one master has. Provides the right 2765 * functionality in a bridge. 2766 */ 2767 skb_bond_set_mac_by_master(skb, master); 2768 } 2769 2770 if (dev->priv_flags & IFF_SLAVE_INACTIVE) { 2771 if ((dev->priv_flags & IFF_SLAVE_NEEDARP) && 2772 skb->protocol == __cpu_to_be16(ETH_P_ARP)) 2773 return 0; 2774 2775 if (master->priv_flags & IFF_MASTER_ALB) { 2776 if (skb->pkt_type != PACKET_BROADCAST && 2777 skb->pkt_type != PACKET_MULTICAST) 2778 return 0; 2779 } 2780 if (master->priv_flags & IFF_MASTER_8023AD && 2781 skb->protocol == __cpu_to_be16(ETH_P_SLOW)) 2782 return 0; 2783 2784 return 1; 2785 } 2786 return 0; 2787 } 2788 EXPORT_SYMBOL(__skb_bond_should_drop); 2789 2790 static int __netif_receive_skb(struct sk_buff *skb) 2791 { 2792 struct packet_type *ptype, *pt_prev; 2793 struct net_device *orig_dev; 2794 struct net_device *master; 2795 struct net_device *null_or_orig; 2796 struct net_device *orig_or_bond; 2797 int ret = NET_RX_DROP; 2798 __be16 type; 2799 2800 if (!netdev_tstamp_prequeue) 2801 net_timestamp_check(skb); 2802 2803 if (vlan_tx_tag_present(skb) && vlan_hwaccel_do_receive(skb)) 2804 return NET_RX_SUCCESS; 2805 2806 /* if we've gotten here through NAPI, check netpoll */ 2807 if (netpoll_receive_skb(skb)) 2808 return NET_RX_DROP; 2809 2810 if (!skb->skb_iif) 2811 skb->skb_iif = skb->dev->ifindex; 2812 2813 /* 2814 * bonding note: skbs received on inactive slaves should only 2815 * be delivered to pkt handlers that are exact matches. Also 2816 * the deliver_no_wcard flag will be set. If packet handlers 2817 * are sensitive to duplicate packets these skbs will need to 2818 * be dropped at the handler. The vlan accel path may have 2819 * already set the deliver_no_wcard flag. 2820 */ 2821 null_or_orig = NULL; 2822 orig_dev = skb->dev; 2823 master = ACCESS_ONCE(orig_dev->master); 2824 if (skb->deliver_no_wcard) 2825 null_or_orig = orig_dev; 2826 else if (master) { 2827 if (skb_bond_should_drop(skb, master)) { 2828 skb->deliver_no_wcard = 1; 2829 null_or_orig = orig_dev; /* deliver only exact match */ 2830 } else 2831 skb->dev = master; 2832 } 2833 2834 __get_cpu_var(softnet_data).processed++; 2835 2836 skb_reset_network_header(skb); 2837 skb_reset_transport_header(skb); 2838 skb->mac_len = skb->network_header - skb->mac_header; 2839 2840 pt_prev = NULL; 2841 2842 rcu_read_lock(); 2843 2844 #ifdef CONFIG_NET_CLS_ACT 2845 if (skb->tc_verd & TC_NCLS) { 2846 skb->tc_verd = CLR_TC_NCLS(skb->tc_verd); 2847 goto ncls; 2848 } 2849 #endif 2850 2851 list_for_each_entry_rcu(ptype, &ptype_all, list) { 2852 if (ptype->dev == null_or_orig || ptype->dev == skb->dev || 2853 ptype->dev == orig_dev) { 2854 if (pt_prev) 2855 ret = deliver_skb(skb, pt_prev, orig_dev); 2856 pt_prev = ptype; 2857 } 2858 } 2859 2860 #ifdef CONFIG_NET_CLS_ACT 2861 skb = handle_ing(skb, &pt_prev, &ret, orig_dev); 2862 if (!skb) 2863 goto out; 2864 ncls: 2865 #endif 2866 2867 skb = handle_bridge(skb, &pt_prev, &ret, orig_dev); 2868 if (!skb) 2869 goto out; 2870 skb = handle_macvlan(skb, &pt_prev, &ret, orig_dev); 2871 if (!skb) 2872 goto out; 2873 2874 /* 2875 * Make sure frames received on VLAN interfaces stacked on 2876 * bonding interfaces still make their way to any base bonding 2877 * device that may have registered for a specific ptype. The 2878 * handler may have to adjust skb->dev and orig_dev. 2879 */ 2880 orig_or_bond = orig_dev; 2881 if ((skb->dev->priv_flags & IFF_802_1Q_VLAN) && 2882 (vlan_dev_real_dev(skb->dev)->priv_flags & IFF_BONDING)) { 2883 orig_or_bond = vlan_dev_real_dev(skb->dev); 2884 } 2885 2886 type = skb->protocol; 2887 list_for_each_entry_rcu(ptype, 2888 &ptype_base[ntohs(type) & PTYPE_HASH_MASK], list) { 2889 if (ptype->type == type && (ptype->dev == null_or_orig || 2890 ptype->dev == skb->dev || ptype->dev == orig_dev || 2891 ptype->dev == orig_or_bond)) { 2892 if (pt_prev) 2893 ret = deliver_skb(skb, pt_prev, orig_dev); 2894 pt_prev = ptype; 2895 } 2896 } 2897 2898 if (pt_prev) { 2899 ret = pt_prev->func(skb, skb->dev, pt_prev, orig_dev); 2900 } else { 2901 kfree_skb(skb); 2902 /* Jamal, now you will not able to escape explaining 2903 * me how you were going to use this. :-) 2904 */ 2905 ret = NET_RX_DROP; 2906 } 2907 2908 out: 2909 rcu_read_unlock(); 2910 return ret; 2911 } 2912 2913 /** 2914 * netif_receive_skb - process receive buffer from network 2915 * @skb: buffer to process 2916 * 2917 * netif_receive_skb() is the main receive data processing function. 2918 * It always succeeds. The buffer may be dropped during processing 2919 * for congestion control or by the protocol layers. 2920 * 2921 * This function may only be called from softirq context and interrupts 2922 * should be enabled. 2923 * 2924 * Return values (usually ignored): 2925 * NET_RX_SUCCESS: no congestion 2926 * NET_RX_DROP: packet was dropped 2927 */ 2928 int netif_receive_skb(struct sk_buff *skb) 2929 { 2930 if (netdev_tstamp_prequeue) 2931 net_timestamp_check(skb); 2932 2933 #ifdef CONFIG_RPS 2934 { 2935 struct rps_dev_flow voidflow, *rflow = &voidflow; 2936 int cpu, ret; 2937 2938 rcu_read_lock(); 2939 2940 cpu = get_rps_cpu(skb->dev, skb, &rflow); 2941 2942 if (cpu >= 0) { 2943 ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail); 2944 rcu_read_unlock(); 2945 } else { 2946 rcu_read_unlock(); 2947 ret = __netif_receive_skb(skb); 2948 } 2949 2950 return ret; 2951 } 2952 #else 2953 return __netif_receive_skb(skb); 2954 #endif 2955 } 2956 EXPORT_SYMBOL(netif_receive_skb); 2957 2958 /* Network device is going away, flush any packets still pending 2959 * Called with irqs disabled. 2960 */ 2961 static void flush_backlog(void *arg) 2962 { 2963 struct net_device *dev = arg; 2964 struct softnet_data *sd = &__get_cpu_var(softnet_data); 2965 struct sk_buff *skb, *tmp; 2966 2967 rps_lock(sd); 2968 skb_queue_walk_safe(&sd->input_pkt_queue, skb, tmp) { 2969 if (skb->dev == dev) { 2970 __skb_unlink(skb, &sd->input_pkt_queue); 2971 kfree_skb(skb); 2972 input_queue_head_incr(sd); 2973 } 2974 } 2975 rps_unlock(sd); 2976 2977 skb_queue_walk_safe(&sd->process_queue, skb, tmp) { 2978 if (skb->dev == dev) { 2979 __skb_unlink(skb, &sd->process_queue); 2980 kfree_skb(skb); 2981 input_queue_head_incr(sd); 2982 } 2983 } 2984 } 2985 2986 static int napi_gro_complete(struct sk_buff *skb) 2987 { 2988 struct packet_type *ptype; 2989 __be16 type = skb->protocol; 2990 struct list_head *head = &ptype_base[ntohs(type) & PTYPE_HASH_MASK]; 2991 int err = -ENOENT; 2992 2993 if (NAPI_GRO_CB(skb)->count == 1) { 2994 skb_shinfo(skb)->gso_size = 0; 2995 goto out; 2996 } 2997 2998 rcu_read_lock(); 2999 list_for_each_entry_rcu(ptype, head, list) { 3000 if (ptype->type != type || ptype->dev || !ptype->gro_complete) 3001 continue; 3002 3003 err = ptype->gro_complete(skb); 3004 break; 3005 } 3006 rcu_read_unlock(); 3007 3008 if (err) { 3009 WARN_ON(&ptype->list == head); 3010 kfree_skb(skb); 3011 return NET_RX_SUCCESS; 3012 } 3013 3014 out: 3015 return netif_receive_skb(skb); 3016 } 3017 3018 static void napi_gro_flush(struct napi_struct *napi) 3019 { 3020 struct sk_buff *skb, *next; 3021 3022 for (skb = napi->gro_list; skb; skb = next) { 3023 next = skb->next; 3024 skb->next = NULL; 3025 napi_gro_complete(skb); 3026 } 3027 3028 napi->gro_count = 0; 3029 napi->gro_list = NULL; 3030 } 3031 3032 enum gro_result dev_gro_receive(struct napi_struct *napi, struct sk_buff *skb) 3033 { 3034 struct sk_buff **pp = NULL; 3035 struct packet_type *ptype; 3036 __be16 type = skb->protocol; 3037 struct list_head *head = &ptype_base[ntohs(type) & PTYPE_HASH_MASK]; 3038 int same_flow; 3039 int mac_len; 3040 enum gro_result ret; 3041 3042 if (!(skb->dev->features & NETIF_F_GRO)) 3043 goto normal; 3044 3045 if (skb_is_gso(skb) || skb_has_frags(skb)) 3046 goto normal; 3047 3048 rcu_read_lock(); 3049 list_for_each_entry_rcu(ptype, head, list) { 3050 if (ptype->type != type || ptype->dev || !ptype->gro_receive) 3051 continue; 3052 3053 skb_set_network_header(skb, skb_gro_offset(skb)); 3054 mac_len = skb->network_header - skb->mac_header; 3055 skb->mac_len = mac_len; 3056 NAPI_GRO_CB(skb)->same_flow = 0; 3057 NAPI_GRO_CB(skb)->flush = 0; 3058 NAPI_GRO_CB(skb)->free = 0; 3059 3060 pp = ptype->gro_receive(&napi->gro_list, skb); 3061 break; 3062 } 3063 rcu_read_unlock(); 3064 3065 if (&ptype->list == head) 3066 goto normal; 3067 3068 same_flow = NAPI_GRO_CB(skb)->same_flow; 3069 ret = NAPI_GRO_CB(skb)->free ? GRO_MERGED_FREE : GRO_MERGED; 3070 3071 if (pp) { 3072 struct sk_buff *nskb = *pp; 3073 3074 *pp = nskb->next; 3075 nskb->next = NULL; 3076 napi_gro_complete(nskb); 3077 napi->gro_count--; 3078 } 3079 3080 if (same_flow) 3081 goto ok; 3082 3083 if (NAPI_GRO_CB(skb)->flush || napi->gro_count >= MAX_GRO_SKBS) 3084 goto normal; 3085 3086 napi->gro_count++; 3087 NAPI_GRO_CB(skb)->count = 1; 3088 skb_shinfo(skb)->gso_size = skb_gro_len(skb); 3089 skb->next = napi->gro_list; 3090 napi->gro_list = skb; 3091 ret = GRO_HELD; 3092 3093 pull: 3094 if (skb_headlen(skb) < skb_gro_offset(skb)) { 3095 int grow = skb_gro_offset(skb) - skb_headlen(skb); 3096 3097 BUG_ON(skb->end - skb->tail < grow); 3098 3099 memcpy(skb_tail_pointer(skb), NAPI_GRO_CB(skb)->frag0, grow); 3100 3101 skb->tail += grow; 3102 skb->data_len -= grow; 3103 3104 skb_shinfo(skb)->frags[0].page_offset += grow; 3105 skb_shinfo(skb)->frags[0].size -= grow; 3106 3107 if (unlikely(!skb_shinfo(skb)->frags[0].size)) { 3108 put_page(skb_shinfo(skb)->frags[0].page); 3109 memmove(skb_shinfo(skb)->frags, 3110 skb_shinfo(skb)->frags + 1, 3111 --skb_shinfo(skb)->nr_frags); 3112 } 3113 } 3114 3115 ok: 3116 return ret; 3117 3118 normal: 3119 ret = GRO_NORMAL; 3120 goto pull; 3121 } 3122 EXPORT_SYMBOL(dev_gro_receive); 3123 3124 static gro_result_t 3125 __napi_gro_receive(struct napi_struct *napi, struct sk_buff *skb) 3126 { 3127 struct sk_buff *p; 3128 3129 if (netpoll_rx_on(skb)) 3130 return GRO_NORMAL; 3131 3132 for (p = napi->gro_list; p; p = p->next) { 3133 NAPI_GRO_CB(p)->same_flow = 3134 (p->dev == skb->dev) && 3135 !compare_ether_header(skb_mac_header(p), 3136 skb_gro_mac_header(skb)); 3137 NAPI_GRO_CB(p)->flush = 0; 3138 } 3139 3140 return dev_gro_receive(napi, skb); 3141 } 3142 3143 gro_result_t napi_skb_finish(gro_result_t ret, struct sk_buff *skb) 3144 { 3145 switch (ret) { 3146 case GRO_NORMAL: 3147 if (netif_receive_skb(skb)) 3148 ret = GRO_DROP; 3149 break; 3150 3151 case GRO_DROP: 3152 case GRO_MERGED_FREE: 3153 kfree_skb(skb); 3154 break; 3155 3156 case GRO_HELD: 3157 case GRO_MERGED: 3158 break; 3159 } 3160 3161 return ret; 3162 } 3163 EXPORT_SYMBOL(napi_skb_finish); 3164 3165 void skb_gro_reset_offset(struct sk_buff *skb) 3166 { 3167 NAPI_GRO_CB(skb)->data_offset = 0; 3168 NAPI_GRO_CB(skb)->frag0 = NULL; 3169 NAPI_GRO_CB(skb)->frag0_len = 0; 3170 3171 if (skb->mac_header == skb->tail && 3172 !PageHighMem(skb_shinfo(skb)->frags[0].page)) { 3173 NAPI_GRO_CB(skb)->frag0 = 3174 page_address(skb_shinfo(skb)->frags[0].page) + 3175 skb_shinfo(skb)->frags[0].page_offset; 3176 NAPI_GRO_CB(skb)->frag0_len = skb_shinfo(skb)->frags[0].size; 3177 } 3178 } 3179 EXPORT_SYMBOL(skb_gro_reset_offset); 3180 3181 gro_result_t napi_gro_receive(struct napi_struct *napi, struct sk_buff *skb) 3182 { 3183 skb_gro_reset_offset(skb); 3184 3185 return napi_skb_finish(__napi_gro_receive(napi, skb), skb); 3186 } 3187 EXPORT_SYMBOL(napi_gro_receive); 3188 3189 void napi_reuse_skb(struct napi_struct *napi, struct sk_buff *skb) 3190 { 3191 __skb_pull(skb, skb_headlen(skb)); 3192 skb_reserve(skb, NET_IP_ALIGN - skb_headroom(skb)); 3193 3194 napi->skb = skb; 3195 } 3196 EXPORT_SYMBOL(napi_reuse_skb); 3197 3198 struct sk_buff *napi_get_frags(struct napi_struct *napi) 3199 { 3200 struct sk_buff *skb = napi->skb; 3201 3202 if (!skb) { 3203 skb = netdev_alloc_skb_ip_align(napi->dev, GRO_MAX_HEAD); 3204 if (skb) 3205 napi->skb = skb; 3206 } 3207 return skb; 3208 } 3209 EXPORT_SYMBOL(napi_get_frags); 3210 3211 gro_result_t napi_frags_finish(struct napi_struct *napi, struct sk_buff *skb, 3212 gro_result_t ret) 3213 { 3214 switch (ret) { 3215 case GRO_NORMAL: 3216 case GRO_HELD: 3217 skb->protocol = eth_type_trans(skb, skb->dev); 3218 3219 if (ret == GRO_HELD) 3220 skb_gro_pull(skb, -ETH_HLEN); 3221 else if (netif_receive_skb(skb)) 3222 ret = GRO_DROP; 3223 break; 3224 3225 case GRO_DROP: 3226 case GRO_MERGED_FREE: 3227 napi_reuse_skb(napi, skb); 3228 break; 3229 3230 case GRO_MERGED: 3231 break; 3232 } 3233 3234 return ret; 3235 } 3236 EXPORT_SYMBOL(napi_frags_finish); 3237 3238 struct sk_buff *napi_frags_skb(struct napi_struct *napi) 3239 { 3240 struct sk_buff *skb = napi->skb; 3241 struct ethhdr *eth; 3242 unsigned int hlen; 3243 unsigned int off; 3244 3245 napi->skb = NULL; 3246 3247 skb_reset_mac_header(skb); 3248 skb_gro_reset_offset(skb); 3249 3250 off = skb_gro_offset(skb); 3251 hlen = off + sizeof(*eth); 3252 eth = skb_gro_header_fast(skb, off); 3253 if (skb_gro_header_hard(skb, hlen)) { 3254 eth = skb_gro_header_slow(skb, hlen, off); 3255 if (unlikely(!eth)) { 3256 napi_reuse_skb(napi, skb); 3257 skb = NULL; 3258 goto out; 3259 } 3260 } 3261 3262 skb_gro_pull(skb, sizeof(*eth)); 3263 3264 /* 3265 * This works because the only protocols we care about don't require 3266 * special handling. We'll fix it up properly at the end. 3267 */ 3268 skb->protocol = eth->h_proto; 3269 3270 out: 3271 return skb; 3272 } 3273 EXPORT_SYMBOL(napi_frags_skb); 3274 3275 gro_result_t napi_gro_frags(struct napi_struct *napi) 3276 { 3277 struct sk_buff *skb = napi_frags_skb(napi); 3278 3279 if (!skb) 3280 return GRO_DROP; 3281 3282 return napi_frags_finish(napi, skb, __napi_gro_receive(napi, skb)); 3283 } 3284 EXPORT_SYMBOL(napi_gro_frags); 3285 3286 /* 3287 * net_rps_action sends any pending IPI's for rps. 3288 * Note: called with local irq disabled, but exits with local irq enabled. 3289 */ 3290 static void net_rps_action_and_irq_enable(struct softnet_data *sd) 3291 { 3292 #ifdef CONFIG_RPS 3293 struct softnet_data *remsd = sd->rps_ipi_list; 3294 3295 if (remsd) { 3296 sd->rps_ipi_list = NULL; 3297 3298 local_irq_enable(); 3299 3300 /* Send pending IPI's to kick RPS processing on remote cpus. */ 3301 while (remsd) { 3302 struct softnet_data *next = remsd->rps_ipi_next; 3303 3304 if (cpu_online(remsd->cpu)) 3305 __smp_call_function_single(remsd->cpu, 3306 &remsd->csd, 0); 3307 remsd = next; 3308 } 3309 } else 3310 #endif 3311 local_irq_enable(); 3312 } 3313 3314 static int process_backlog(struct napi_struct *napi, int quota) 3315 { 3316 int work = 0; 3317 struct softnet_data *sd = container_of(napi, struct softnet_data, backlog); 3318 3319 #ifdef CONFIG_RPS 3320 /* Check if we have pending ipi, its better to send them now, 3321 * not waiting net_rx_action() end. 3322 */ 3323 if (sd->rps_ipi_list) { 3324 local_irq_disable(); 3325 net_rps_action_and_irq_enable(sd); 3326 } 3327 #endif 3328 napi->weight = weight_p; 3329 local_irq_disable(); 3330 while (work < quota) { 3331 struct sk_buff *skb; 3332 unsigned int qlen; 3333 3334 while ((skb = __skb_dequeue(&sd->process_queue))) { 3335 local_irq_enable(); 3336 __netif_receive_skb(skb); 3337 local_irq_disable(); 3338 input_queue_head_incr(sd); 3339 if (++work >= quota) { 3340 local_irq_enable(); 3341 return work; 3342 } 3343 } 3344 3345 rps_lock(sd); 3346 qlen = skb_queue_len(&sd->input_pkt_queue); 3347 if (qlen) 3348 skb_queue_splice_tail_init(&sd->input_pkt_queue, 3349 &sd->process_queue); 3350 3351 if (qlen < quota - work) { 3352 /* 3353 * Inline a custom version of __napi_complete(). 3354 * only current cpu owns and manipulates this napi, 3355 * and NAPI_STATE_SCHED is the only possible flag set on backlog. 3356 * we can use a plain write instead of clear_bit(), 3357 * and we dont need an smp_mb() memory barrier. 3358 */ 3359 list_del(&napi->poll_list); 3360 napi->state = 0; 3361 3362 quota = work + qlen; 3363 } 3364 rps_unlock(sd); 3365 } 3366 local_irq_enable(); 3367 3368 return work; 3369 } 3370 3371 /** 3372 * __napi_schedule - schedule for receive 3373 * @n: entry to schedule 3374 * 3375 * The entry's receive function will be scheduled to run 3376 */ 3377 void __napi_schedule(struct napi_struct *n) 3378 { 3379 unsigned long flags; 3380 3381 local_irq_save(flags); 3382 ____napi_schedule(&__get_cpu_var(softnet_data), n); 3383 local_irq_restore(flags); 3384 } 3385 EXPORT_SYMBOL(__napi_schedule); 3386 3387 void __napi_complete(struct napi_struct *n) 3388 { 3389 BUG_ON(!test_bit(NAPI_STATE_SCHED, &n->state)); 3390 BUG_ON(n->gro_list); 3391 3392 list_del(&n->poll_list); 3393 smp_mb__before_clear_bit(); 3394 clear_bit(NAPI_STATE_SCHED, &n->state); 3395 } 3396 EXPORT_SYMBOL(__napi_complete); 3397 3398 void napi_complete(struct napi_struct *n) 3399 { 3400 unsigned long flags; 3401 3402 /* 3403 * don't let napi dequeue from the cpu poll list 3404 * just in case its running on a different cpu 3405 */ 3406 if (unlikely(test_bit(NAPI_STATE_NPSVC, &n->state))) 3407 return; 3408 3409 napi_gro_flush(n); 3410 local_irq_save(flags); 3411 __napi_complete(n); 3412 local_irq_restore(flags); 3413 } 3414 EXPORT_SYMBOL(napi_complete); 3415 3416 void netif_napi_add(struct net_device *dev, struct napi_struct *napi, 3417 int (*poll)(struct napi_struct *, int), int weight) 3418 { 3419 INIT_LIST_HEAD(&napi->poll_list); 3420 napi->gro_count = 0; 3421 napi->gro_list = NULL; 3422 napi->skb = NULL; 3423 napi->poll = poll; 3424 napi->weight = weight; 3425 list_add(&napi->dev_list, &dev->napi_list); 3426 napi->dev = dev; 3427 #ifdef CONFIG_NETPOLL 3428 spin_lock_init(&napi->poll_lock); 3429 napi->poll_owner = -1; 3430 #endif 3431 set_bit(NAPI_STATE_SCHED, &napi->state); 3432 } 3433 EXPORT_SYMBOL(netif_napi_add); 3434 3435 void netif_napi_del(struct napi_struct *napi) 3436 { 3437 struct sk_buff *skb, *next; 3438 3439 list_del_init(&napi->dev_list); 3440 napi_free_frags(napi); 3441 3442 for (skb = napi->gro_list; skb; skb = next) { 3443 next = skb->next; 3444 skb->next = NULL; 3445 kfree_skb(skb); 3446 } 3447 3448 napi->gro_list = NULL; 3449 napi->gro_count = 0; 3450 } 3451 EXPORT_SYMBOL(netif_napi_del); 3452 3453 static void net_rx_action(struct softirq_action *h) 3454 { 3455 struct softnet_data *sd = &__get_cpu_var(softnet_data); 3456 unsigned long time_limit = jiffies + 2; 3457 int budget = netdev_budget; 3458 void *have; 3459 3460 local_irq_disable(); 3461 3462 while (!list_empty(&sd->poll_list)) { 3463 struct napi_struct *n; 3464 int work, weight; 3465 3466 /* If softirq window is exhuasted then punt. 3467 * Allow this to run for 2 jiffies since which will allow 3468 * an average latency of 1.5/HZ. 3469 */ 3470 if (unlikely(budget <= 0 || time_after(jiffies, time_limit))) 3471 goto softnet_break; 3472 3473 local_irq_enable(); 3474 3475 /* Even though interrupts have been re-enabled, this 3476 * access is safe because interrupts can only add new 3477 * entries to the tail of this list, and only ->poll() 3478 * calls can remove this head entry from the list. 3479 */ 3480 n = list_first_entry(&sd->poll_list, struct napi_struct, poll_list); 3481 3482 have = netpoll_poll_lock(n); 3483 3484 weight = n->weight; 3485 3486 /* This NAPI_STATE_SCHED test is for avoiding a race 3487 * with netpoll's poll_napi(). Only the entity which 3488 * obtains the lock and sees NAPI_STATE_SCHED set will 3489 * actually make the ->poll() call. Therefore we avoid 3490 * accidently calling ->poll() when NAPI is not scheduled. 3491 */ 3492 work = 0; 3493 if (test_bit(NAPI_STATE_SCHED, &n->state)) { 3494 work = n->poll(n, weight); 3495 trace_napi_poll(n); 3496 } 3497 3498 WARN_ON_ONCE(work > weight); 3499 3500 budget -= work; 3501 3502 local_irq_disable(); 3503 3504 /* Drivers must not modify the NAPI state if they 3505 * consume the entire weight. In such cases this code 3506 * still "owns" the NAPI instance and therefore can 3507 * move the instance around on the list at-will. 3508 */ 3509 if (unlikely(work == weight)) { 3510 if (unlikely(napi_disable_pending(n))) { 3511 local_irq_enable(); 3512 napi_complete(n); 3513 local_irq_disable(); 3514 } else 3515 list_move_tail(&n->poll_list, &sd->poll_list); 3516 } 3517 3518 netpoll_poll_unlock(have); 3519 } 3520 out: 3521 net_rps_action_and_irq_enable(sd); 3522 3523 #ifdef CONFIG_NET_DMA 3524 /* 3525 * There may not be any more sk_buffs coming right now, so push 3526 * any pending DMA copies to hardware 3527 */ 3528 dma_issue_pending_all(); 3529 #endif 3530 3531 return; 3532 3533 softnet_break: 3534 sd->time_squeeze++; 3535 __raise_softirq_irqoff(NET_RX_SOFTIRQ); 3536 goto out; 3537 } 3538 3539 static gifconf_func_t *gifconf_list[NPROTO]; 3540 3541 /** 3542 * register_gifconf - register a SIOCGIF handler 3543 * @family: Address family 3544 * @gifconf: Function handler 3545 * 3546 * Register protocol dependent address dumping routines. The handler 3547 * that is passed must not be freed or reused until it has been replaced 3548 * by another handler. 3549 */ 3550 int register_gifconf(unsigned int family, gifconf_func_t *gifconf) 3551 { 3552 if (family >= NPROTO) 3553 return -EINVAL; 3554 gifconf_list[family] = gifconf; 3555 return 0; 3556 } 3557 EXPORT_SYMBOL(register_gifconf); 3558 3559 3560 /* 3561 * Map an interface index to its name (SIOCGIFNAME) 3562 */ 3563 3564 /* 3565 * We need this ioctl for efficient implementation of the 3566 * if_indextoname() function required by the IPv6 API. Without 3567 * it, we would have to search all the interfaces to find a 3568 * match. --pb 3569 */ 3570 3571 static int dev_ifname(struct net *net, struct ifreq __user *arg) 3572 { 3573 struct net_device *dev; 3574 struct ifreq ifr; 3575 3576 /* 3577 * Fetch the caller's info block. 3578 */ 3579 3580 if (copy_from_user(&ifr, arg, sizeof(struct ifreq))) 3581 return -EFAULT; 3582 3583 rcu_read_lock(); 3584 dev = dev_get_by_index_rcu(net, ifr.ifr_ifindex); 3585 if (!dev) { 3586 rcu_read_unlock(); 3587 return -ENODEV; 3588 } 3589 3590 strcpy(ifr.ifr_name, dev->name); 3591 rcu_read_unlock(); 3592 3593 if (copy_to_user(arg, &ifr, sizeof(struct ifreq))) 3594 return -EFAULT; 3595 return 0; 3596 } 3597 3598 /* 3599 * Perform a SIOCGIFCONF call. This structure will change 3600 * size eventually, and there is nothing I can do about it. 3601 * Thus we will need a 'compatibility mode'. 3602 */ 3603 3604 static int dev_ifconf(struct net *net, char __user *arg) 3605 { 3606 struct ifconf ifc; 3607 struct net_device *dev; 3608 char __user *pos; 3609 int len; 3610 int total; 3611 int i; 3612 3613 /* 3614 * Fetch the caller's info block. 3615 */ 3616 3617 if (copy_from_user(&ifc, arg, sizeof(struct ifconf))) 3618 return -EFAULT; 3619 3620 pos = ifc.ifc_buf; 3621 len = ifc.ifc_len; 3622 3623 /* 3624 * Loop over the interfaces, and write an info block for each. 3625 */ 3626 3627 total = 0; 3628 for_each_netdev(net, dev) { 3629 for (i = 0; i < NPROTO; i++) { 3630 if (gifconf_list[i]) { 3631 int done; 3632 if (!pos) 3633 done = gifconf_list[i](dev, NULL, 0); 3634 else 3635 done = gifconf_list[i](dev, pos + total, 3636 len - total); 3637 if (done < 0) 3638 return -EFAULT; 3639 total += done; 3640 } 3641 } 3642 } 3643 3644 /* 3645 * All done. Write the updated control block back to the caller. 3646 */ 3647 ifc.ifc_len = total; 3648 3649 /* 3650 * Both BSD and Solaris return 0 here, so we do too. 3651 */ 3652 return copy_to_user(arg, &ifc, sizeof(struct ifconf)) ? -EFAULT : 0; 3653 } 3654 3655 #ifdef CONFIG_PROC_FS 3656 /* 3657 * This is invoked by the /proc filesystem handler to display a device 3658 * in detail. 3659 */ 3660 void *dev_seq_start(struct seq_file *seq, loff_t *pos) 3661 __acquires(RCU) 3662 { 3663 struct net *net = seq_file_net(seq); 3664 loff_t off; 3665 struct net_device *dev; 3666 3667 rcu_read_lock(); 3668 if (!*pos) 3669 return SEQ_START_TOKEN; 3670 3671 off = 1; 3672 for_each_netdev_rcu(net, dev) 3673 if (off++ == *pos) 3674 return dev; 3675 3676 return NULL; 3677 } 3678 3679 void *dev_seq_next(struct seq_file *seq, void *v, loff_t *pos) 3680 { 3681 struct net_device *dev = (v == SEQ_START_TOKEN) ? 3682 first_net_device(seq_file_net(seq)) : 3683 next_net_device((struct net_device *)v); 3684 3685 ++*pos; 3686 return rcu_dereference(dev); 3687 } 3688 3689 void dev_seq_stop(struct seq_file *seq, void *v) 3690 __releases(RCU) 3691 { 3692 rcu_read_unlock(); 3693 } 3694 3695 static void dev_seq_printf_stats(struct seq_file *seq, struct net_device *dev) 3696 { 3697 const struct net_device_stats *stats = dev_get_stats(dev); 3698 3699 seq_printf(seq, "%6s: %7lu %7lu %4lu %4lu %4lu %5lu %10lu %9lu " 3700 "%8lu %7lu %4lu %4lu %4lu %5lu %7lu %10lu\n", 3701 dev->name, stats->rx_bytes, stats->rx_packets, 3702 stats->rx_errors, 3703 stats->rx_dropped + stats->rx_missed_errors, 3704 stats->rx_fifo_errors, 3705 stats->rx_length_errors + stats->rx_over_errors + 3706 stats->rx_crc_errors + stats->rx_frame_errors, 3707 stats->rx_compressed, stats->multicast, 3708 stats->tx_bytes, stats->tx_packets, 3709 stats->tx_errors, stats->tx_dropped, 3710 stats->tx_fifo_errors, stats->collisions, 3711 stats->tx_carrier_errors + 3712 stats->tx_aborted_errors + 3713 stats->tx_window_errors + 3714 stats->tx_heartbeat_errors, 3715 stats->tx_compressed); 3716 } 3717 3718 /* 3719 * Called from the PROCfs module. This now uses the new arbitrary sized 3720 * /proc/net interface to create /proc/net/dev 3721 */ 3722 static int dev_seq_show(struct seq_file *seq, void *v) 3723 { 3724 if (v == SEQ_START_TOKEN) 3725 seq_puts(seq, "Inter-| Receive " 3726 " | Transmit\n" 3727 " face |bytes packets errs drop fifo frame " 3728 "compressed multicast|bytes packets errs " 3729 "drop fifo colls carrier compressed\n"); 3730 else 3731 dev_seq_printf_stats(seq, v); 3732 return 0; 3733 } 3734 3735 static struct softnet_data *softnet_get_online(loff_t *pos) 3736 { 3737 struct softnet_data *sd = NULL; 3738 3739 while (*pos < nr_cpu_ids) 3740 if (cpu_online(*pos)) { 3741 sd = &per_cpu(softnet_data, *pos); 3742 break; 3743 } else 3744 ++*pos; 3745 return sd; 3746 } 3747 3748 static void *softnet_seq_start(struct seq_file *seq, loff_t *pos) 3749 { 3750 return softnet_get_online(pos); 3751 } 3752 3753 static void *softnet_seq_next(struct seq_file *seq, void *v, loff_t *pos) 3754 { 3755 ++*pos; 3756 return softnet_get_online(pos); 3757 } 3758 3759 static void softnet_seq_stop(struct seq_file *seq, void *v) 3760 { 3761 } 3762 3763 static int softnet_seq_show(struct seq_file *seq, void *v) 3764 { 3765 struct softnet_data *sd = v; 3766 3767 seq_printf(seq, "%08x %08x %08x %08x %08x %08x %08x %08x %08x %08x\n", 3768 sd->processed, sd->dropped, sd->time_squeeze, 0, 3769 0, 0, 0, 0, /* was fastroute */ 3770 sd->cpu_collision, sd->received_rps); 3771 return 0; 3772 } 3773 3774 static const struct seq_operations dev_seq_ops = { 3775 .start = dev_seq_start, 3776 .next = dev_seq_next, 3777 .stop = dev_seq_stop, 3778 .show = dev_seq_show, 3779 }; 3780 3781 static int dev_seq_open(struct inode *inode, struct file *file) 3782 { 3783 return seq_open_net(inode, file, &dev_seq_ops, 3784 sizeof(struct seq_net_private)); 3785 } 3786 3787 static const struct file_operations dev_seq_fops = { 3788 .owner = THIS_MODULE, 3789 .open = dev_seq_open, 3790 .read = seq_read, 3791 .llseek = seq_lseek, 3792 .release = seq_release_net, 3793 }; 3794 3795 static const struct seq_operations softnet_seq_ops = { 3796 .start = softnet_seq_start, 3797 .next = softnet_seq_next, 3798 .stop = softnet_seq_stop, 3799 .show = softnet_seq_show, 3800 }; 3801 3802 static int softnet_seq_open(struct inode *inode, struct file *file) 3803 { 3804 return seq_open(file, &softnet_seq_ops); 3805 } 3806 3807 static const struct file_operations softnet_seq_fops = { 3808 .owner = THIS_MODULE, 3809 .open = softnet_seq_open, 3810 .read = seq_read, 3811 .llseek = seq_lseek, 3812 .release = seq_release, 3813 }; 3814 3815 static void *ptype_get_idx(loff_t pos) 3816 { 3817 struct packet_type *pt = NULL; 3818 loff_t i = 0; 3819 int t; 3820 3821 list_for_each_entry_rcu(pt, &ptype_all, list) { 3822 if (i == pos) 3823 return pt; 3824 ++i; 3825 } 3826 3827 for (t = 0; t < PTYPE_HASH_SIZE; t++) { 3828 list_for_each_entry_rcu(pt, &ptype_base[t], list) { 3829 if (i == pos) 3830 return pt; 3831 ++i; 3832 } 3833 } 3834 return NULL; 3835 } 3836 3837 static void *ptype_seq_start(struct seq_file *seq, loff_t *pos) 3838 __acquires(RCU) 3839 { 3840 rcu_read_lock(); 3841 return *pos ? ptype_get_idx(*pos - 1) : SEQ_START_TOKEN; 3842 } 3843 3844 static void *ptype_seq_next(struct seq_file *seq, void *v, loff_t *pos) 3845 { 3846 struct packet_type *pt; 3847 struct list_head *nxt; 3848 int hash; 3849 3850 ++*pos; 3851 if (v == SEQ_START_TOKEN) 3852 return ptype_get_idx(0); 3853 3854 pt = v; 3855 nxt = pt->list.next; 3856 if (pt->type == htons(ETH_P_ALL)) { 3857 if (nxt != &ptype_all) 3858 goto found; 3859 hash = 0; 3860 nxt = ptype_base[0].next; 3861 } else 3862 hash = ntohs(pt->type) & PTYPE_HASH_MASK; 3863 3864 while (nxt == &ptype_base[hash]) { 3865 if (++hash >= PTYPE_HASH_SIZE) 3866 return NULL; 3867 nxt = ptype_base[hash].next; 3868 } 3869 found: 3870 return list_entry(nxt, struct packet_type, list); 3871 } 3872 3873 static void ptype_seq_stop(struct seq_file *seq, void *v) 3874 __releases(RCU) 3875 { 3876 rcu_read_unlock(); 3877 } 3878 3879 static int ptype_seq_show(struct seq_file *seq, void *v) 3880 { 3881 struct packet_type *pt = v; 3882 3883 if (v == SEQ_START_TOKEN) 3884 seq_puts(seq, "Type Device Function\n"); 3885 else if (pt->dev == NULL || dev_net(pt->dev) == seq_file_net(seq)) { 3886 if (pt->type == htons(ETH_P_ALL)) 3887 seq_puts(seq, "ALL "); 3888 else 3889 seq_printf(seq, "%04x", ntohs(pt->type)); 3890 3891 seq_printf(seq, " %-8s %pF\n", 3892 pt->dev ? pt->dev->name : "", pt->func); 3893 } 3894 3895 return 0; 3896 } 3897 3898 static const struct seq_operations ptype_seq_ops = { 3899 .start = ptype_seq_start, 3900 .next = ptype_seq_next, 3901 .stop = ptype_seq_stop, 3902 .show = ptype_seq_show, 3903 }; 3904 3905 static int ptype_seq_open(struct inode *inode, struct file *file) 3906 { 3907 return seq_open_net(inode, file, &ptype_seq_ops, 3908 sizeof(struct seq_net_private)); 3909 } 3910 3911 static const struct file_operations ptype_seq_fops = { 3912 .owner = THIS_MODULE, 3913 .open = ptype_seq_open, 3914 .read = seq_read, 3915 .llseek = seq_lseek, 3916 .release = seq_release_net, 3917 }; 3918 3919 3920 static int __net_init dev_proc_net_init(struct net *net) 3921 { 3922 int rc = -ENOMEM; 3923 3924 if (!proc_net_fops_create(net, "dev", S_IRUGO, &dev_seq_fops)) 3925 goto out; 3926 if (!proc_net_fops_create(net, "softnet_stat", S_IRUGO, &softnet_seq_fops)) 3927 goto out_dev; 3928 if (!proc_net_fops_create(net, "ptype", S_IRUGO, &ptype_seq_fops)) 3929 goto out_softnet; 3930 3931 if (wext_proc_init(net)) 3932 goto out_ptype; 3933 rc = 0; 3934 out: 3935 return rc; 3936 out_ptype: 3937 proc_net_remove(net, "ptype"); 3938 out_softnet: 3939 proc_net_remove(net, "softnet_stat"); 3940 out_dev: 3941 proc_net_remove(net, "dev"); 3942 goto out; 3943 } 3944 3945 static void __net_exit dev_proc_net_exit(struct net *net) 3946 { 3947 wext_proc_exit(net); 3948 3949 proc_net_remove(net, "ptype"); 3950 proc_net_remove(net, "softnet_stat"); 3951 proc_net_remove(net, "dev"); 3952 } 3953 3954 static struct pernet_operations __net_initdata dev_proc_ops = { 3955 .init = dev_proc_net_init, 3956 .exit = dev_proc_net_exit, 3957 }; 3958 3959 static int __init dev_proc_init(void) 3960 { 3961 return register_pernet_subsys(&dev_proc_ops); 3962 } 3963 #else 3964 #define dev_proc_init() 0 3965 #endif /* CONFIG_PROC_FS */ 3966 3967 3968 /** 3969 * netdev_set_master - set up master/slave pair 3970 * @slave: slave device 3971 * @master: new master device 3972 * 3973 * Changes the master device of the slave. Pass %NULL to break the 3974 * bonding. The caller must hold the RTNL semaphore. On a failure 3975 * a negative errno code is returned. On success the reference counts 3976 * are adjusted, %RTM_NEWLINK is sent to the routing socket and the 3977 * function returns zero. 3978 */ 3979 int netdev_set_master(struct net_device *slave, struct net_device *master) 3980 { 3981 struct net_device *old = slave->master; 3982 3983 ASSERT_RTNL(); 3984 3985 if (master) { 3986 if (old) 3987 return -EBUSY; 3988 dev_hold(master); 3989 } 3990 3991 slave->master = master; 3992 3993 if (old) { 3994 synchronize_net(); 3995 dev_put(old); 3996 } 3997 if (master) 3998 slave->flags |= IFF_SLAVE; 3999 else 4000 slave->flags &= ~IFF_SLAVE; 4001 4002 rtmsg_ifinfo(RTM_NEWLINK, slave, IFF_SLAVE); 4003 return 0; 4004 } 4005 EXPORT_SYMBOL(netdev_set_master); 4006 4007 static void dev_change_rx_flags(struct net_device *dev, int flags) 4008 { 4009 const struct net_device_ops *ops = dev->netdev_ops; 4010 4011 if ((dev->flags & IFF_UP) && ops->ndo_change_rx_flags) 4012 ops->ndo_change_rx_flags(dev, flags); 4013 } 4014 4015 static int __dev_set_promiscuity(struct net_device *dev, int inc) 4016 { 4017 unsigned short old_flags = dev->flags; 4018 uid_t uid; 4019 gid_t gid; 4020 4021 ASSERT_RTNL(); 4022 4023 dev->flags |= IFF_PROMISC; 4024 dev->promiscuity += inc; 4025 if (dev->promiscuity == 0) { 4026 /* 4027 * Avoid overflow. 4028 * If inc causes overflow, untouch promisc and return error. 4029 */ 4030 if (inc < 0) 4031 dev->flags &= ~IFF_PROMISC; 4032 else { 4033 dev->promiscuity -= inc; 4034 printk(KERN_WARNING "%s: promiscuity touches roof, " 4035 "set promiscuity failed, promiscuity feature " 4036 "of device might be broken.\n", dev->name); 4037 return -EOVERFLOW; 4038 } 4039 } 4040 if (dev->flags != old_flags) { 4041 printk(KERN_INFO "device %s %s promiscuous mode\n", 4042 dev->name, (dev->flags & IFF_PROMISC) ? "entered" : 4043 "left"); 4044 if (audit_enabled) { 4045 current_uid_gid(&uid, &gid); 4046 audit_log(current->audit_context, GFP_ATOMIC, 4047 AUDIT_ANOM_PROMISCUOUS, 4048 "dev=%s prom=%d old_prom=%d auid=%u uid=%u gid=%u ses=%u", 4049 dev->name, (dev->flags & IFF_PROMISC), 4050 (old_flags & IFF_PROMISC), 4051 audit_get_loginuid(current), 4052 uid, gid, 4053 audit_get_sessionid(current)); 4054 } 4055 4056 dev_change_rx_flags(dev, IFF_PROMISC); 4057 } 4058 return 0; 4059 } 4060 4061 /** 4062 * dev_set_promiscuity - update promiscuity count on a device 4063 * @dev: device 4064 * @inc: modifier 4065 * 4066 * Add or remove promiscuity from a device. While the count in the device 4067 * remains above zero the interface remains promiscuous. Once it hits zero 4068 * the device reverts back to normal filtering operation. A negative inc 4069 * value is used to drop promiscuity on the device. 4070 * Return 0 if successful or a negative errno code on error. 4071 */ 4072 int dev_set_promiscuity(struct net_device *dev, int inc) 4073 { 4074 unsigned short old_flags = dev->flags; 4075 int err; 4076 4077 err = __dev_set_promiscuity(dev, inc); 4078 if (err < 0) 4079 return err; 4080 if (dev->flags != old_flags) 4081 dev_set_rx_mode(dev); 4082 return err; 4083 } 4084 EXPORT_SYMBOL(dev_set_promiscuity); 4085 4086 /** 4087 * dev_set_allmulti - update allmulti count on a device 4088 * @dev: device 4089 * @inc: modifier 4090 * 4091 * Add or remove reception of all multicast frames to a device. While the 4092 * count in the device remains above zero the interface remains listening 4093 * to all interfaces. Once it hits zero the device reverts back to normal 4094 * filtering operation. A negative @inc value is used to drop the counter 4095 * when releasing a resource needing all multicasts. 4096 * Return 0 if successful or a negative errno code on error. 4097 */ 4098 4099 int dev_set_allmulti(struct net_device *dev, int inc) 4100 { 4101 unsigned short old_flags = dev->flags; 4102 4103 ASSERT_RTNL(); 4104 4105 dev->flags |= IFF_ALLMULTI; 4106 dev->allmulti += inc; 4107 if (dev->allmulti == 0) { 4108 /* 4109 * Avoid overflow. 4110 * If inc causes overflow, untouch allmulti and return error. 4111 */ 4112 if (inc < 0) 4113 dev->flags &= ~IFF_ALLMULTI; 4114 else { 4115 dev->allmulti -= inc; 4116 printk(KERN_WARNING "%s: allmulti touches roof, " 4117 "set allmulti failed, allmulti feature of " 4118 "device might be broken.\n", dev->name); 4119 return -EOVERFLOW; 4120 } 4121 } 4122 if (dev->flags ^ old_flags) { 4123 dev_change_rx_flags(dev, IFF_ALLMULTI); 4124 dev_set_rx_mode(dev); 4125 } 4126 return 0; 4127 } 4128 EXPORT_SYMBOL(dev_set_allmulti); 4129 4130 /* 4131 * Upload unicast and multicast address lists to device and 4132 * configure RX filtering. When the device doesn't support unicast 4133 * filtering it is put in promiscuous mode while unicast addresses 4134 * are present. 4135 */ 4136 void __dev_set_rx_mode(struct net_device *dev) 4137 { 4138 const struct net_device_ops *ops = dev->netdev_ops; 4139 4140 /* dev_open will call this function so the list will stay sane. */ 4141 if (!(dev->flags&IFF_UP)) 4142 return; 4143 4144 if (!netif_device_present(dev)) 4145 return; 4146 4147 if (ops->ndo_set_rx_mode) 4148 ops->ndo_set_rx_mode(dev); 4149 else { 4150 /* Unicast addresses changes may only happen under the rtnl, 4151 * therefore calling __dev_set_promiscuity here is safe. 4152 */ 4153 if (!netdev_uc_empty(dev) && !dev->uc_promisc) { 4154 __dev_set_promiscuity(dev, 1); 4155 dev->uc_promisc = 1; 4156 } else if (netdev_uc_empty(dev) && dev->uc_promisc) { 4157 __dev_set_promiscuity(dev, -1); 4158 dev->uc_promisc = 0; 4159 } 4160 4161 if (ops->ndo_set_multicast_list) 4162 ops->ndo_set_multicast_list(dev); 4163 } 4164 } 4165 4166 void dev_set_rx_mode(struct net_device *dev) 4167 { 4168 netif_addr_lock_bh(dev); 4169 __dev_set_rx_mode(dev); 4170 netif_addr_unlock_bh(dev); 4171 } 4172 4173 /** 4174 * dev_get_flags - get flags reported to userspace 4175 * @dev: device 4176 * 4177 * Get the combination of flag bits exported through APIs to userspace. 4178 */ 4179 unsigned dev_get_flags(const struct net_device *dev) 4180 { 4181 unsigned flags; 4182 4183 flags = (dev->flags & ~(IFF_PROMISC | 4184 IFF_ALLMULTI | 4185 IFF_RUNNING | 4186 IFF_LOWER_UP | 4187 IFF_DORMANT)) | 4188 (dev->gflags & (IFF_PROMISC | 4189 IFF_ALLMULTI)); 4190 4191 if (netif_running(dev)) { 4192 if (netif_oper_up(dev)) 4193 flags |= IFF_RUNNING; 4194 if (netif_carrier_ok(dev)) 4195 flags |= IFF_LOWER_UP; 4196 if (netif_dormant(dev)) 4197 flags |= IFF_DORMANT; 4198 } 4199 4200 return flags; 4201 } 4202 EXPORT_SYMBOL(dev_get_flags); 4203 4204 int __dev_change_flags(struct net_device *dev, unsigned int flags) 4205 { 4206 int old_flags = dev->flags; 4207 int ret; 4208 4209 ASSERT_RTNL(); 4210 4211 /* 4212 * Set the flags on our device. 4213 */ 4214 4215 dev->flags = (flags & (IFF_DEBUG | IFF_NOTRAILERS | IFF_NOARP | 4216 IFF_DYNAMIC | IFF_MULTICAST | IFF_PORTSEL | 4217 IFF_AUTOMEDIA)) | 4218 (dev->flags & (IFF_UP | IFF_VOLATILE | IFF_PROMISC | 4219 IFF_ALLMULTI)); 4220 4221 /* 4222 * Load in the correct multicast list now the flags have changed. 4223 */ 4224 4225 if ((old_flags ^ flags) & IFF_MULTICAST) 4226 dev_change_rx_flags(dev, IFF_MULTICAST); 4227 4228 dev_set_rx_mode(dev); 4229 4230 /* 4231 * Have we downed the interface. We handle IFF_UP ourselves 4232 * according to user attempts to set it, rather than blindly 4233 * setting it. 4234 */ 4235 4236 ret = 0; 4237 if ((old_flags ^ flags) & IFF_UP) { /* Bit is different ? */ 4238 ret = ((old_flags & IFF_UP) ? __dev_close : __dev_open)(dev); 4239 4240 if (!ret) 4241 dev_set_rx_mode(dev); 4242 } 4243 4244 if ((flags ^ dev->gflags) & IFF_PROMISC) { 4245 int inc = (flags & IFF_PROMISC) ? 1 : -1; 4246 4247 dev->gflags ^= IFF_PROMISC; 4248 dev_set_promiscuity(dev, inc); 4249 } 4250 4251 /* NOTE: order of synchronization of IFF_PROMISC and IFF_ALLMULTI 4252 is important. Some (broken) drivers set IFF_PROMISC, when 4253 IFF_ALLMULTI is requested not asking us and not reporting. 4254 */ 4255 if ((flags ^ dev->gflags) & IFF_ALLMULTI) { 4256 int inc = (flags & IFF_ALLMULTI) ? 1 : -1; 4257 4258 dev->gflags ^= IFF_ALLMULTI; 4259 dev_set_allmulti(dev, inc); 4260 } 4261 4262 return ret; 4263 } 4264 4265 void __dev_notify_flags(struct net_device *dev, unsigned int old_flags) 4266 { 4267 unsigned int changes = dev->flags ^ old_flags; 4268 4269 if (changes & IFF_UP) { 4270 if (dev->flags & IFF_UP) 4271 call_netdevice_notifiers(NETDEV_UP, dev); 4272 else 4273 call_netdevice_notifiers(NETDEV_DOWN, dev); 4274 } 4275 4276 if (dev->flags & IFF_UP && 4277 (changes & ~(IFF_UP | IFF_PROMISC | IFF_ALLMULTI | IFF_VOLATILE))) 4278 call_netdevice_notifiers(NETDEV_CHANGE, dev); 4279 } 4280 4281 /** 4282 * dev_change_flags - change device settings 4283 * @dev: device 4284 * @flags: device state flags 4285 * 4286 * Change settings on device based state flags. The flags are 4287 * in the userspace exported format. 4288 */ 4289 int dev_change_flags(struct net_device *dev, unsigned flags) 4290 { 4291 int ret, changes; 4292 int old_flags = dev->flags; 4293 4294 ret = __dev_change_flags(dev, flags); 4295 if (ret < 0) 4296 return ret; 4297 4298 changes = old_flags ^ dev->flags; 4299 if (changes) 4300 rtmsg_ifinfo(RTM_NEWLINK, dev, changes); 4301 4302 __dev_notify_flags(dev, old_flags); 4303 return ret; 4304 } 4305 EXPORT_SYMBOL(dev_change_flags); 4306 4307 /** 4308 * dev_set_mtu - Change maximum transfer unit 4309 * @dev: device 4310 * @new_mtu: new transfer unit 4311 * 4312 * Change the maximum transfer size of the network device. 4313 */ 4314 int dev_set_mtu(struct net_device *dev, int new_mtu) 4315 { 4316 const struct net_device_ops *ops = dev->netdev_ops; 4317 int err; 4318 4319 if (new_mtu == dev->mtu) 4320 return 0; 4321 4322 /* MTU must be positive. */ 4323 if (new_mtu < 0) 4324 return -EINVAL; 4325 4326 if (!netif_device_present(dev)) 4327 return -ENODEV; 4328 4329 err = 0; 4330 if (ops->ndo_change_mtu) 4331 err = ops->ndo_change_mtu(dev, new_mtu); 4332 else 4333 dev->mtu = new_mtu; 4334 4335 if (!err && dev->flags & IFF_UP) 4336 call_netdevice_notifiers(NETDEV_CHANGEMTU, dev); 4337 return err; 4338 } 4339 EXPORT_SYMBOL(dev_set_mtu); 4340 4341 /** 4342 * dev_set_mac_address - Change Media Access Control Address 4343 * @dev: device 4344 * @sa: new address 4345 * 4346 * Change the hardware (MAC) address of the device 4347 */ 4348 int dev_set_mac_address(struct net_device *dev, struct sockaddr *sa) 4349 { 4350 const struct net_device_ops *ops = dev->netdev_ops; 4351 int err; 4352 4353 if (!ops->ndo_set_mac_address) 4354 return -EOPNOTSUPP; 4355 if (sa->sa_family != dev->type) 4356 return -EINVAL; 4357 if (!netif_device_present(dev)) 4358 return -ENODEV; 4359 err = ops->ndo_set_mac_address(dev, sa); 4360 if (!err) 4361 call_netdevice_notifiers(NETDEV_CHANGEADDR, dev); 4362 return err; 4363 } 4364 EXPORT_SYMBOL(dev_set_mac_address); 4365 4366 /* 4367 * Perform the SIOCxIFxxx calls, inside rcu_read_lock() 4368 */ 4369 static int dev_ifsioc_locked(struct net *net, struct ifreq *ifr, unsigned int cmd) 4370 { 4371 int err; 4372 struct net_device *dev = dev_get_by_name_rcu(net, ifr->ifr_name); 4373 4374 if (!dev) 4375 return -ENODEV; 4376 4377 switch (cmd) { 4378 case SIOCGIFFLAGS: /* Get interface flags */ 4379 ifr->ifr_flags = (short) dev_get_flags(dev); 4380 return 0; 4381 4382 case SIOCGIFMETRIC: /* Get the metric on the interface 4383 (currently unused) */ 4384 ifr->ifr_metric = 0; 4385 return 0; 4386 4387 case SIOCGIFMTU: /* Get the MTU of a device */ 4388 ifr->ifr_mtu = dev->mtu; 4389 return 0; 4390 4391 case SIOCGIFHWADDR: 4392 if (!dev->addr_len) 4393 memset(ifr->ifr_hwaddr.sa_data, 0, sizeof ifr->ifr_hwaddr.sa_data); 4394 else 4395 memcpy(ifr->ifr_hwaddr.sa_data, dev->dev_addr, 4396 min(sizeof ifr->ifr_hwaddr.sa_data, (size_t) dev->addr_len)); 4397 ifr->ifr_hwaddr.sa_family = dev->type; 4398 return 0; 4399 4400 case SIOCGIFSLAVE: 4401 err = -EINVAL; 4402 break; 4403 4404 case SIOCGIFMAP: 4405 ifr->ifr_map.mem_start = dev->mem_start; 4406 ifr->ifr_map.mem_end = dev->mem_end; 4407 ifr->ifr_map.base_addr = dev->base_addr; 4408 ifr->ifr_map.irq = dev->irq; 4409 ifr->ifr_map.dma = dev->dma; 4410 ifr->ifr_map.port = dev->if_port; 4411 return 0; 4412 4413 case SIOCGIFINDEX: 4414 ifr->ifr_ifindex = dev->ifindex; 4415 return 0; 4416 4417 case SIOCGIFTXQLEN: 4418 ifr->ifr_qlen = dev->tx_queue_len; 4419 return 0; 4420 4421 default: 4422 /* dev_ioctl() should ensure this case 4423 * is never reached 4424 */ 4425 WARN_ON(1); 4426 err = -EINVAL; 4427 break; 4428 4429 } 4430 return err; 4431 } 4432 4433 /* 4434 * Perform the SIOCxIFxxx calls, inside rtnl_lock() 4435 */ 4436 static int dev_ifsioc(struct net *net, struct ifreq *ifr, unsigned int cmd) 4437 { 4438 int err; 4439 struct net_device *dev = __dev_get_by_name(net, ifr->ifr_name); 4440 const struct net_device_ops *ops; 4441 4442 if (!dev) 4443 return -ENODEV; 4444 4445 ops = dev->netdev_ops; 4446 4447 switch (cmd) { 4448 case SIOCSIFFLAGS: /* Set interface flags */ 4449 return dev_change_flags(dev, ifr->ifr_flags); 4450 4451 case SIOCSIFMETRIC: /* Set the metric on the interface 4452 (currently unused) */ 4453 return -EOPNOTSUPP; 4454 4455 case SIOCSIFMTU: /* Set the MTU of a device */ 4456 return dev_set_mtu(dev, ifr->ifr_mtu); 4457 4458 case SIOCSIFHWADDR: 4459 return dev_set_mac_address(dev, &ifr->ifr_hwaddr); 4460 4461 case SIOCSIFHWBROADCAST: 4462 if (ifr->ifr_hwaddr.sa_family != dev->type) 4463 return -EINVAL; 4464 memcpy(dev->broadcast, ifr->ifr_hwaddr.sa_data, 4465 min(sizeof ifr->ifr_hwaddr.sa_data, (size_t) dev->addr_len)); 4466 call_netdevice_notifiers(NETDEV_CHANGEADDR, dev); 4467 return 0; 4468 4469 case SIOCSIFMAP: 4470 if (ops->ndo_set_config) { 4471 if (!netif_device_present(dev)) 4472 return -ENODEV; 4473 return ops->ndo_set_config(dev, &ifr->ifr_map); 4474 } 4475 return -EOPNOTSUPP; 4476 4477 case SIOCADDMULTI: 4478 if ((!ops->ndo_set_multicast_list && !ops->ndo_set_rx_mode) || 4479 ifr->ifr_hwaddr.sa_family != AF_UNSPEC) 4480 return -EINVAL; 4481 if (!netif_device_present(dev)) 4482 return -ENODEV; 4483 return dev_mc_add_global(dev, ifr->ifr_hwaddr.sa_data); 4484 4485 case SIOCDELMULTI: 4486 if ((!ops->ndo_set_multicast_list && !ops->ndo_set_rx_mode) || 4487 ifr->ifr_hwaddr.sa_family != AF_UNSPEC) 4488 return -EINVAL; 4489 if (!netif_device_present(dev)) 4490 return -ENODEV; 4491 return dev_mc_del_global(dev, ifr->ifr_hwaddr.sa_data); 4492 4493 case SIOCSIFTXQLEN: 4494 if (ifr->ifr_qlen < 0) 4495 return -EINVAL; 4496 dev->tx_queue_len = ifr->ifr_qlen; 4497 return 0; 4498 4499 case SIOCSIFNAME: 4500 ifr->ifr_newname[IFNAMSIZ-1] = '\0'; 4501 return dev_change_name(dev, ifr->ifr_newname); 4502 4503 /* 4504 * Unknown or private ioctl 4505 */ 4506 default: 4507 if ((cmd >= SIOCDEVPRIVATE && 4508 cmd <= SIOCDEVPRIVATE + 15) || 4509 cmd == SIOCBONDENSLAVE || 4510 cmd == SIOCBONDRELEASE || 4511 cmd == SIOCBONDSETHWADDR || 4512 cmd == SIOCBONDSLAVEINFOQUERY || 4513 cmd == SIOCBONDINFOQUERY || 4514 cmd == SIOCBONDCHANGEACTIVE || 4515 cmd == SIOCGMIIPHY || 4516 cmd == SIOCGMIIREG || 4517 cmd == SIOCSMIIREG || 4518 cmd == SIOCBRADDIF || 4519 cmd == SIOCBRDELIF || 4520 cmd == SIOCSHWTSTAMP || 4521 cmd == SIOCWANDEV) { 4522 err = -EOPNOTSUPP; 4523 if (ops->ndo_do_ioctl) { 4524 if (netif_device_present(dev)) 4525 err = ops->ndo_do_ioctl(dev, ifr, cmd); 4526 else 4527 err = -ENODEV; 4528 } 4529 } else 4530 err = -EINVAL; 4531 4532 } 4533 return err; 4534 } 4535 4536 /* 4537 * This function handles all "interface"-type I/O control requests. The actual 4538 * 'doing' part of this is dev_ifsioc above. 4539 */ 4540 4541 /** 4542 * dev_ioctl - network device ioctl 4543 * @net: the applicable net namespace 4544 * @cmd: command to issue 4545 * @arg: pointer to a struct ifreq in user space 4546 * 4547 * Issue ioctl functions to devices. This is normally called by the 4548 * user space syscall interfaces but can sometimes be useful for 4549 * other purposes. The return value is the return from the syscall if 4550 * positive or a negative errno code on error. 4551 */ 4552 4553 int dev_ioctl(struct net *net, unsigned int cmd, void __user *arg) 4554 { 4555 struct ifreq ifr; 4556 int ret; 4557 char *colon; 4558 4559 /* One special case: SIOCGIFCONF takes ifconf argument 4560 and requires shared lock, because it sleeps writing 4561 to user space. 4562 */ 4563 4564 if (cmd == SIOCGIFCONF) { 4565 rtnl_lock(); 4566 ret = dev_ifconf(net, (char __user *) arg); 4567 rtnl_unlock(); 4568 return ret; 4569 } 4570 if (cmd == SIOCGIFNAME) 4571 return dev_ifname(net, (struct ifreq __user *)arg); 4572 4573 if (copy_from_user(&ifr, arg, sizeof(struct ifreq))) 4574 return -EFAULT; 4575 4576 ifr.ifr_name[IFNAMSIZ-1] = 0; 4577 4578 colon = strchr(ifr.ifr_name, ':'); 4579 if (colon) 4580 *colon = 0; 4581 4582 /* 4583 * See which interface the caller is talking about. 4584 */ 4585 4586 switch (cmd) { 4587 /* 4588 * These ioctl calls: 4589 * - can be done by all. 4590 * - atomic and do not require locking. 4591 * - return a value 4592 */ 4593 case SIOCGIFFLAGS: 4594 case SIOCGIFMETRIC: 4595 case SIOCGIFMTU: 4596 case SIOCGIFHWADDR: 4597 case SIOCGIFSLAVE: 4598 case SIOCGIFMAP: 4599 case SIOCGIFINDEX: 4600 case SIOCGIFTXQLEN: 4601 dev_load(net, ifr.ifr_name); 4602 rcu_read_lock(); 4603 ret = dev_ifsioc_locked(net, &ifr, cmd); 4604 rcu_read_unlock(); 4605 if (!ret) { 4606 if (colon) 4607 *colon = ':'; 4608 if (copy_to_user(arg, &ifr, 4609 sizeof(struct ifreq))) 4610 ret = -EFAULT; 4611 } 4612 return ret; 4613 4614 case SIOCETHTOOL: 4615 dev_load(net, ifr.ifr_name); 4616 rtnl_lock(); 4617 ret = dev_ethtool(net, &ifr); 4618 rtnl_unlock(); 4619 if (!ret) { 4620 if (colon) 4621 *colon = ':'; 4622 if (copy_to_user(arg, &ifr, 4623 sizeof(struct ifreq))) 4624 ret = -EFAULT; 4625 } 4626 return ret; 4627 4628 /* 4629 * These ioctl calls: 4630 * - require superuser power. 4631 * - require strict serialization. 4632 * - return a value 4633 */ 4634 case SIOCGMIIPHY: 4635 case SIOCGMIIREG: 4636 case SIOCSIFNAME: 4637 if (!capable(CAP_NET_ADMIN)) 4638 return -EPERM; 4639 dev_load(net, ifr.ifr_name); 4640 rtnl_lock(); 4641 ret = dev_ifsioc(net, &ifr, cmd); 4642 rtnl_unlock(); 4643 if (!ret) { 4644 if (colon) 4645 *colon = ':'; 4646 if (copy_to_user(arg, &ifr, 4647 sizeof(struct ifreq))) 4648 ret = -EFAULT; 4649 } 4650 return ret; 4651 4652 /* 4653 * These ioctl calls: 4654 * - require superuser power. 4655 * - require strict serialization. 4656 * - do not return a value 4657 */ 4658 case SIOCSIFFLAGS: 4659 case SIOCSIFMETRIC: 4660 case SIOCSIFMTU: 4661 case SIOCSIFMAP: 4662 case SIOCSIFHWADDR: 4663 case SIOCSIFSLAVE: 4664 case SIOCADDMULTI: 4665 case SIOCDELMULTI: 4666 case SIOCSIFHWBROADCAST: 4667 case SIOCSIFTXQLEN: 4668 case SIOCSMIIREG: 4669 case SIOCBONDENSLAVE: 4670 case SIOCBONDRELEASE: 4671 case SIOCBONDSETHWADDR: 4672 case SIOCBONDCHANGEACTIVE: 4673 case SIOCBRADDIF: 4674 case SIOCBRDELIF: 4675 case SIOCSHWTSTAMP: 4676 if (!capable(CAP_NET_ADMIN)) 4677 return -EPERM; 4678 /* fall through */ 4679 case SIOCBONDSLAVEINFOQUERY: 4680 case SIOCBONDINFOQUERY: 4681 dev_load(net, ifr.ifr_name); 4682 rtnl_lock(); 4683 ret = dev_ifsioc(net, &ifr, cmd); 4684 rtnl_unlock(); 4685 return ret; 4686 4687 case SIOCGIFMEM: 4688 /* Get the per device memory space. We can add this but 4689 * currently do not support it */ 4690 case SIOCSIFMEM: 4691 /* Set the per device memory buffer space. 4692 * Not applicable in our case */ 4693 case SIOCSIFLINK: 4694 return -EINVAL; 4695 4696 /* 4697 * Unknown or private ioctl. 4698 */ 4699 default: 4700 if (cmd == SIOCWANDEV || 4701 (cmd >= SIOCDEVPRIVATE && 4702 cmd <= SIOCDEVPRIVATE + 15)) { 4703 dev_load(net, ifr.ifr_name); 4704 rtnl_lock(); 4705 ret = dev_ifsioc(net, &ifr, cmd); 4706 rtnl_unlock(); 4707 if (!ret && copy_to_user(arg, &ifr, 4708 sizeof(struct ifreq))) 4709 ret = -EFAULT; 4710 return ret; 4711 } 4712 /* Take care of Wireless Extensions */ 4713 if (cmd >= SIOCIWFIRST && cmd <= SIOCIWLAST) 4714 return wext_handle_ioctl(net, &ifr, cmd, arg); 4715 return -EINVAL; 4716 } 4717 } 4718 4719 4720 /** 4721 * dev_new_index - allocate an ifindex 4722 * @net: the applicable net namespace 4723 * 4724 * Returns a suitable unique value for a new device interface 4725 * number. The caller must hold the rtnl semaphore or the 4726 * dev_base_lock to be sure it remains unique. 4727 */ 4728 static int dev_new_index(struct net *net) 4729 { 4730 static int ifindex; 4731 for (;;) { 4732 if (++ifindex <= 0) 4733 ifindex = 1; 4734 if (!__dev_get_by_index(net, ifindex)) 4735 return ifindex; 4736 } 4737 } 4738 4739 /* Delayed registration/unregisteration */ 4740 static LIST_HEAD(net_todo_list); 4741 4742 static void net_set_todo(struct net_device *dev) 4743 { 4744 list_add_tail(&dev->todo_list, &net_todo_list); 4745 } 4746 4747 static void rollback_registered_many(struct list_head *head) 4748 { 4749 struct net_device *dev, *tmp; 4750 4751 BUG_ON(dev_boot_phase); 4752 ASSERT_RTNL(); 4753 4754 list_for_each_entry_safe(dev, tmp, head, unreg_list) { 4755 /* Some devices call without registering 4756 * for initialization unwind. Remove those 4757 * devices and proceed with the remaining. 4758 */ 4759 if (dev->reg_state == NETREG_UNINITIALIZED) { 4760 pr_debug("unregister_netdevice: device %s/%p never " 4761 "was registered\n", dev->name, dev); 4762 4763 WARN_ON(1); 4764 list_del(&dev->unreg_list); 4765 continue; 4766 } 4767 4768 BUG_ON(dev->reg_state != NETREG_REGISTERED); 4769 4770 /* If device is running, close it first. */ 4771 dev_close(dev); 4772 4773 /* And unlink it from device chain. */ 4774 unlist_netdevice(dev); 4775 4776 dev->reg_state = NETREG_UNREGISTERING; 4777 } 4778 4779 synchronize_net(); 4780 4781 list_for_each_entry(dev, head, unreg_list) { 4782 /* Shutdown queueing discipline. */ 4783 dev_shutdown(dev); 4784 4785 4786 /* Notify protocols, that we are about to destroy 4787 this device. They should clean all the things. 4788 */ 4789 call_netdevice_notifiers(NETDEV_UNREGISTER, dev); 4790 4791 if (!dev->rtnl_link_ops || 4792 dev->rtnl_link_state == RTNL_LINK_INITIALIZED) 4793 rtmsg_ifinfo(RTM_DELLINK, dev, ~0U); 4794 4795 /* 4796 * Flush the unicast and multicast chains 4797 */ 4798 dev_uc_flush(dev); 4799 dev_mc_flush(dev); 4800 4801 if (dev->netdev_ops->ndo_uninit) 4802 dev->netdev_ops->ndo_uninit(dev); 4803 4804 /* Notifier chain MUST detach us from master device. */ 4805 WARN_ON(dev->master); 4806 4807 /* Remove entries from kobject tree */ 4808 netdev_unregister_kobject(dev); 4809 } 4810 4811 /* Process any work delayed until the end of the batch */ 4812 dev = list_first_entry(head, struct net_device, unreg_list); 4813 call_netdevice_notifiers(NETDEV_UNREGISTER_BATCH, dev); 4814 4815 synchronize_net(); 4816 4817 list_for_each_entry(dev, head, unreg_list) 4818 dev_put(dev); 4819 } 4820 4821 static void rollback_registered(struct net_device *dev) 4822 { 4823 LIST_HEAD(single); 4824 4825 list_add(&dev->unreg_list, &single); 4826 rollback_registered_many(&single); 4827 } 4828 4829 static void __netdev_init_queue_locks_one(struct net_device *dev, 4830 struct netdev_queue *dev_queue, 4831 void *_unused) 4832 { 4833 spin_lock_init(&dev_queue->_xmit_lock); 4834 netdev_set_xmit_lockdep_class(&dev_queue->_xmit_lock, dev->type); 4835 dev_queue->xmit_lock_owner = -1; 4836 } 4837 4838 static void netdev_init_queue_locks(struct net_device *dev) 4839 { 4840 netdev_for_each_tx_queue(dev, __netdev_init_queue_locks_one, NULL); 4841 __netdev_init_queue_locks_one(dev, &dev->rx_queue, NULL); 4842 } 4843 4844 unsigned long netdev_fix_features(unsigned long features, const char *name) 4845 { 4846 /* Fix illegal SG+CSUM combinations. */ 4847 if ((features & NETIF_F_SG) && 4848 !(features & NETIF_F_ALL_CSUM)) { 4849 if (name) 4850 printk(KERN_NOTICE "%s: Dropping NETIF_F_SG since no " 4851 "checksum feature.\n", name); 4852 features &= ~NETIF_F_SG; 4853 } 4854 4855 /* TSO requires that SG is present as well. */ 4856 if ((features & NETIF_F_TSO) && !(features & NETIF_F_SG)) { 4857 if (name) 4858 printk(KERN_NOTICE "%s: Dropping NETIF_F_TSO since no " 4859 "SG feature.\n", name); 4860 features &= ~NETIF_F_TSO; 4861 } 4862 4863 if (features & NETIF_F_UFO) { 4864 if (!(features & NETIF_F_GEN_CSUM)) { 4865 if (name) 4866 printk(KERN_ERR "%s: Dropping NETIF_F_UFO " 4867 "since no NETIF_F_HW_CSUM feature.\n", 4868 name); 4869 features &= ~NETIF_F_UFO; 4870 } 4871 4872 if (!(features & NETIF_F_SG)) { 4873 if (name) 4874 printk(KERN_ERR "%s: Dropping NETIF_F_UFO " 4875 "since no NETIF_F_SG feature.\n", name); 4876 features &= ~NETIF_F_UFO; 4877 } 4878 } 4879 4880 return features; 4881 } 4882 EXPORT_SYMBOL(netdev_fix_features); 4883 4884 /** 4885 * netif_stacked_transfer_operstate - transfer operstate 4886 * @rootdev: the root or lower level device to transfer state from 4887 * @dev: the device to transfer operstate to 4888 * 4889 * Transfer operational state from root to device. This is normally 4890 * called when a stacking relationship exists between the root 4891 * device and the device(a leaf device). 4892 */ 4893 void netif_stacked_transfer_operstate(const struct net_device *rootdev, 4894 struct net_device *dev) 4895 { 4896 if (rootdev->operstate == IF_OPER_DORMANT) 4897 netif_dormant_on(dev); 4898 else 4899 netif_dormant_off(dev); 4900 4901 if (netif_carrier_ok(rootdev)) { 4902 if (!netif_carrier_ok(dev)) 4903 netif_carrier_on(dev); 4904 } else { 4905 if (netif_carrier_ok(dev)) 4906 netif_carrier_off(dev); 4907 } 4908 } 4909 EXPORT_SYMBOL(netif_stacked_transfer_operstate); 4910 4911 /** 4912 * register_netdevice - register a network device 4913 * @dev: device to register 4914 * 4915 * Take a completed network device structure and add it to the kernel 4916 * interfaces. A %NETDEV_REGISTER message is sent to the netdev notifier 4917 * chain. 0 is returned on success. A negative errno code is returned 4918 * on a failure to set up the device, or if the name is a duplicate. 4919 * 4920 * Callers must hold the rtnl semaphore. You may want 4921 * register_netdev() instead of this. 4922 * 4923 * BUGS: 4924 * The locking appears insufficient to guarantee two parallel registers 4925 * will not get the same name. 4926 */ 4927 4928 int register_netdevice(struct net_device *dev) 4929 { 4930 int ret; 4931 struct net *net = dev_net(dev); 4932 4933 BUG_ON(dev_boot_phase); 4934 ASSERT_RTNL(); 4935 4936 might_sleep(); 4937 4938 /* When net_device's are persistent, this will be fatal. */ 4939 BUG_ON(dev->reg_state != NETREG_UNINITIALIZED); 4940 BUG_ON(!net); 4941 4942 spin_lock_init(&dev->addr_list_lock); 4943 netdev_set_addr_lockdep_class(dev); 4944 netdev_init_queue_locks(dev); 4945 4946 dev->iflink = -1; 4947 4948 #ifdef CONFIG_RPS 4949 if (!dev->num_rx_queues) { 4950 /* 4951 * Allocate a single RX queue if driver never called 4952 * alloc_netdev_mq 4953 */ 4954 4955 dev->_rx = kzalloc(sizeof(struct netdev_rx_queue), GFP_KERNEL); 4956 if (!dev->_rx) { 4957 ret = -ENOMEM; 4958 goto out; 4959 } 4960 4961 dev->_rx->first = dev->_rx; 4962 atomic_set(&dev->_rx->count, 1); 4963 dev->num_rx_queues = 1; 4964 } 4965 #endif 4966 /* Init, if this function is available */ 4967 if (dev->netdev_ops->ndo_init) { 4968 ret = dev->netdev_ops->ndo_init(dev); 4969 if (ret) { 4970 if (ret > 0) 4971 ret = -EIO; 4972 goto out; 4973 } 4974 } 4975 4976 ret = dev_get_valid_name(dev, dev->name, 0); 4977 if (ret) 4978 goto err_uninit; 4979 4980 dev->ifindex = dev_new_index(net); 4981 if (dev->iflink == -1) 4982 dev->iflink = dev->ifindex; 4983 4984 /* Fix illegal checksum combinations */ 4985 if ((dev->features & NETIF_F_HW_CSUM) && 4986 (dev->features & (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))) { 4987 printk(KERN_NOTICE "%s: mixed HW and IP checksum settings.\n", 4988 dev->name); 4989 dev->features &= ~(NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM); 4990 } 4991 4992 if ((dev->features & NETIF_F_NO_CSUM) && 4993 (dev->features & (NETIF_F_HW_CSUM|NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))) { 4994 printk(KERN_NOTICE "%s: mixed no checksumming and other settings.\n", 4995 dev->name); 4996 dev->features &= ~(NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM|NETIF_F_HW_CSUM); 4997 } 4998 4999 dev->features = netdev_fix_features(dev->features, dev->name); 5000 5001 /* Enable software GSO if SG is supported. */ 5002 if (dev->features & NETIF_F_SG) 5003 dev->features |= NETIF_F_GSO; 5004 5005 ret = call_netdevice_notifiers(NETDEV_POST_INIT, dev); 5006 ret = notifier_to_errno(ret); 5007 if (ret) 5008 goto err_uninit; 5009 5010 ret = netdev_register_kobject(dev); 5011 if (ret) 5012 goto err_uninit; 5013 dev->reg_state = NETREG_REGISTERED; 5014 5015 /* 5016 * Default initial state at registry is that the 5017 * device is present. 5018 */ 5019 5020 set_bit(__LINK_STATE_PRESENT, &dev->state); 5021 5022 dev_init_scheduler(dev); 5023 dev_hold(dev); 5024 list_netdevice(dev); 5025 5026 /* Notify protocols, that a new device appeared. */ 5027 ret = call_netdevice_notifiers(NETDEV_REGISTER, dev); 5028 ret = notifier_to_errno(ret); 5029 if (ret) { 5030 rollback_registered(dev); 5031 dev->reg_state = NETREG_UNREGISTERED; 5032 } 5033 /* 5034 * Prevent userspace races by waiting until the network 5035 * device is fully setup before sending notifications. 5036 */ 5037 if (!dev->rtnl_link_ops || 5038 dev->rtnl_link_state == RTNL_LINK_INITIALIZED) 5039 rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U); 5040 5041 out: 5042 return ret; 5043 5044 err_uninit: 5045 if (dev->netdev_ops->ndo_uninit) 5046 dev->netdev_ops->ndo_uninit(dev); 5047 goto out; 5048 } 5049 EXPORT_SYMBOL(register_netdevice); 5050 5051 /** 5052 * init_dummy_netdev - init a dummy network device for NAPI 5053 * @dev: device to init 5054 * 5055 * This takes a network device structure and initialize the minimum 5056 * amount of fields so it can be used to schedule NAPI polls without 5057 * registering a full blown interface. This is to be used by drivers 5058 * that need to tie several hardware interfaces to a single NAPI 5059 * poll scheduler due to HW limitations. 5060 */ 5061 int init_dummy_netdev(struct net_device *dev) 5062 { 5063 /* Clear everything. Note we don't initialize spinlocks 5064 * are they aren't supposed to be taken by any of the 5065 * NAPI code and this dummy netdev is supposed to be 5066 * only ever used for NAPI polls 5067 */ 5068 memset(dev, 0, sizeof(struct net_device)); 5069 5070 /* make sure we BUG if trying to hit standard 5071 * register/unregister code path 5072 */ 5073 dev->reg_state = NETREG_DUMMY; 5074 5075 /* initialize the ref count */ 5076 atomic_set(&dev->refcnt, 1); 5077 5078 /* NAPI wants this */ 5079 INIT_LIST_HEAD(&dev->napi_list); 5080 5081 /* a dummy interface is started by default */ 5082 set_bit(__LINK_STATE_PRESENT, &dev->state); 5083 set_bit(__LINK_STATE_START, &dev->state); 5084 5085 return 0; 5086 } 5087 EXPORT_SYMBOL_GPL(init_dummy_netdev); 5088 5089 5090 /** 5091 * register_netdev - register a network device 5092 * @dev: device to register 5093 * 5094 * Take a completed network device structure and add it to the kernel 5095 * interfaces. A %NETDEV_REGISTER message is sent to the netdev notifier 5096 * chain. 0 is returned on success. A negative errno code is returned 5097 * on a failure to set up the device, or if the name is a duplicate. 5098 * 5099 * This is a wrapper around register_netdevice that takes the rtnl semaphore 5100 * and expands the device name if you passed a format string to 5101 * alloc_netdev. 5102 */ 5103 int register_netdev(struct net_device *dev) 5104 { 5105 int err; 5106 5107 rtnl_lock(); 5108 5109 /* 5110 * If the name is a format string the caller wants us to do a 5111 * name allocation. 5112 */ 5113 if (strchr(dev->name, '%')) { 5114 err = dev_alloc_name(dev, dev->name); 5115 if (err < 0) 5116 goto out; 5117 } 5118 5119 err = register_netdevice(dev); 5120 out: 5121 rtnl_unlock(); 5122 return err; 5123 } 5124 EXPORT_SYMBOL(register_netdev); 5125 5126 /* 5127 * netdev_wait_allrefs - wait until all references are gone. 5128 * 5129 * This is called when unregistering network devices. 5130 * 5131 * Any protocol or device that holds a reference should register 5132 * for netdevice notification, and cleanup and put back the 5133 * reference if they receive an UNREGISTER event. 5134 * We can get stuck here if buggy protocols don't correctly 5135 * call dev_put. 5136 */ 5137 static void netdev_wait_allrefs(struct net_device *dev) 5138 { 5139 unsigned long rebroadcast_time, warning_time; 5140 5141 linkwatch_forget_dev(dev); 5142 5143 rebroadcast_time = warning_time = jiffies; 5144 while (atomic_read(&dev->refcnt) != 0) { 5145 if (time_after(jiffies, rebroadcast_time + 1 * HZ)) { 5146 rtnl_lock(); 5147 5148 /* Rebroadcast unregister notification */ 5149 call_netdevice_notifiers(NETDEV_UNREGISTER, dev); 5150 /* don't resend NETDEV_UNREGISTER_BATCH, _BATCH users 5151 * should have already handle it the first time */ 5152 5153 if (test_bit(__LINK_STATE_LINKWATCH_PENDING, 5154 &dev->state)) { 5155 /* We must not have linkwatch events 5156 * pending on unregister. If this 5157 * happens, we simply run the queue 5158 * unscheduled, resulting in a noop 5159 * for this device. 5160 */ 5161 linkwatch_run_queue(); 5162 } 5163 5164 __rtnl_unlock(); 5165 5166 rebroadcast_time = jiffies; 5167 } 5168 5169 msleep(250); 5170 5171 if (time_after(jiffies, warning_time + 10 * HZ)) { 5172 printk(KERN_EMERG "unregister_netdevice: " 5173 "waiting for %s to become free. Usage " 5174 "count = %d\n", 5175 dev->name, atomic_read(&dev->refcnt)); 5176 warning_time = jiffies; 5177 } 5178 } 5179 } 5180 5181 /* The sequence is: 5182 * 5183 * rtnl_lock(); 5184 * ... 5185 * register_netdevice(x1); 5186 * register_netdevice(x2); 5187 * ... 5188 * unregister_netdevice(y1); 5189 * unregister_netdevice(y2); 5190 * ... 5191 * rtnl_unlock(); 5192 * free_netdev(y1); 5193 * free_netdev(y2); 5194 * 5195 * We are invoked by rtnl_unlock(). 5196 * This allows us to deal with problems: 5197 * 1) We can delete sysfs objects which invoke hotplug 5198 * without deadlocking with linkwatch via keventd. 5199 * 2) Since we run with the RTNL semaphore not held, we can sleep 5200 * safely in order to wait for the netdev refcnt to drop to zero. 5201 * 5202 * We must not return until all unregister events added during 5203 * the interval the lock was held have been completed. 5204 */ 5205 void netdev_run_todo(void) 5206 { 5207 struct list_head list; 5208 5209 /* Snapshot list, allow later requests */ 5210 list_replace_init(&net_todo_list, &list); 5211 5212 __rtnl_unlock(); 5213 5214 while (!list_empty(&list)) { 5215 struct net_device *dev 5216 = list_first_entry(&list, struct net_device, todo_list); 5217 list_del(&dev->todo_list); 5218 5219 if (unlikely(dev->reg_state != NETREG_UNREGISTERING)) { 5220 printk(KERN_ERR "network todo '%s' but state %d\n", 5221 dev->name, dev->reg_state); 5222 dump_stack(); 5223 continue; 5224 } 5225 5226 dev->reg_state = NETREG_UNREGISTERED; 5227 5228 on_each_cpu(flush_backlog, dev, 1); 5229 5230 netdev_wait_allrefs(dev); 5231 5232 /* paranoia */ 5233 BUG_ON(atomic_read(&dev->refcnt)); 5234 WARN_ON(dev->ip_ptr); 5235 WARN_ON(dev->ip6_ptr); 5236 WARN_ON(dev->dn_ptr); 5237 5238 if (dev->destructor) 5239 dev->destructor(dev); 5240 5241 /* Free network device */ 5242 kobject_put(&dev->dev.kobj); 5243 } 5244 } 5245 5246 /** 5247 * dev_txq_stats_fold - fold tx_queues stats 5248 * @dev: device to get statistics from 5249 * @stats: struct net_device_stats to hold results 5250 */ 5251 void dev_txq_stats_fold(const struct net_device *dev, 5252 struct net_device_stats *stats) 5253 { 5254 unsigned long tx_bytes = 0, tx_packets = 0, tx_dropped = 0; 5255 unsigned int i; 5256 struct netdev_queue *txq; 5257 5258 for (i = 0; i < dev->num_tx_queues; i++) { 5259 txq = netdev_get_tx_queue(dev, i); 5260 tx_bytes += txq->tx_bytes; 5261 tx_packets += txq->tx_packets; 5262 tx_dropped += txq->tx_dropped; 5263 } 5264 if (tx_bytes || tx_packets || tx_dropped) { 5265 stats->tx_bytes = tx_bytes; 5266 stats->tx_packets = tx_packets; 5267 stats->tx_dropped = tx_dropped; 5268 } 5269 } 5270 EXPORT_SYMBOL(dev_txq_stats_fold); 5271 5272 /** 5273 * dev_get_stats - get network device statistics 5274 * @dev: device to get statistics from 5275 * 5276 * Get network statistics from device. The device driver may provide 5277 * its own method by setting dev->netdev_ops->get_stats; otherwise 5278 * the internal statistics structure is used. 5279 */ 5280 const struct net_device_stats *dev_get_stats(struct net_device *dev) 5281 { 5282 const struct net_device_ops *ops = dev->netdev_ops; 5283 5284 if (ops->ndo_get_stats) 5285 return ops->ndo_get_stats(dev); 5286 5287 dev_txq_stats_fold(dev, &dev->stats); 5288 return &dev->stats; 5289 } 5290 EXPORT_SYMBOL(dev_get_stats); 5291 5292 static void netdev_init_one_queue(struct net_device *dev, 5293 struct netdev_queue *queue, 5294 void *_unused) 5295 { 5296 queue->dev = dev; 5297 } 5298 5299 static void netdev_init_queues(struct net_device *dev) 5300 { 5301 netdev_init_one_queue(dev, &dev->rx_queue, NULL); 5302 netdev_for_each_tx_queue(dev, netdev_init_one_queue, NULL); 5303 spin_lock_init(&dev->tx_global_lock); 5304 } 5305 5306 /** 5307 * alloc_netdev_mq - allocate network device 5308 * @sizeof_priv: size of private data to allocate space for 5309 * @name: device name format string 5310 * @setup: callback to initialize device 5311 * @queue_count: the number of subqueues to allocate 5312 * 5313 * Allocates a struct net_device with private data area for driver use 5314 * and performs basic initialization. Also allocates subquue structs 5315 * for each queue on the device at the end of the netdevice. 5316 */ 5317 struct net_device *alloc_netdev_mq(int sizeof_priv, const char *name, 5318 void (*setup)(struct net_device *), unsigned int queue_count) 5319 { 5320 struct netdev_queue *tx; 5321 struct net_device *dev; 5322 size_t alloc_size; 5323 struct net_device *p; 5324 #ifdef CONFIG_RPS 5325 struct netdev_rx_queue *rx; 5326 int i; 5327 #endif 5328 5329 BUG_ON(strlen(name) >= sizeof(dev->name)); 5330 5331 alloc_size = sizeof(struct net_device); 5332 if (sizeof_priv) { 5333 /* ensure 32-byte alignment of private area */ 5334 alloc_size = ALIGN(alloc_size, NETDEV_ALIGN); 5335 alloc_size += sizeof_priv; 5336 } 5337 /* ensure 32-byte alignment of whole construct */ 5338 alloc_size += NETDEV_ALIGN - 1; 5339 5340 p = kzalloc(alloc_size, GFP_KERNEL); 5341 if (!p) { 5342 printk(KERN_ERR "alloc_netdev: Unable to allocate device.\n"); 5343 return NULL; 5344 } 5345 5346 tx = kcalloc(queue_count, sizeof(struct netdev_queue), GFP_KERNEL); 5347 if (!tx) { 5348 printk(KERN_ERR "alloc_netdev: Unable to allocate " 5349 "tx qdiscs.\n"); 5350 goto free_p; 5351 } 5352 5353 #ifdef CONFIG_RPS 5354 rx = kcalloc(queue_count, sizeof(struct netdev_rx_queue), GFP_KERNEL); 5355 if (!rx) { 5356 printk(KERN_ERR "alloc_netdev: Unable to allocate " 5357 "rx queues.\n"); 5358 goto free_tx; 5359 } 5360 5361 atomic_set(&rx->count, queue_count); 5362 5363 /* 5364 * Set a pointer to first element in the array which holds the 5365 * reference count. 5366 */ 5367 for (i = 0; i < queue_count; i++) 5368 rx[i].first = rx; 5369 #endif 5370 5371 dev = PTR_ALIGN(p, NETDEV_ALIGN); 5372 dev->padded = (char *)dev - (char *)p; 5373 5374 if (dev_addr_init(dev)) 5375 goto free_rx; 5376 5377 dev_mc_init(dev); 5378 dev_uc_init(dev); 5379 5380 dev_net_set(dev, &init_net); 5381 5382 dev->_tx = tx; 5383 dev->num_tx_queues = queue_count; 5384 dev->real_num_tx_queues = queue_count; 5385 5386 #ifdef CONFIG_RPS 5387 dev->_rx = rx; 5388 dev->num_rx_queues = queue_count; 5389 #endif 5390 5391 dev->gso_max_size = GSO_MAX_SIZE; 5392 5393 netdev_init_queues(dev); 5394 5395 INIT_LIST_HEAD(&dev->ethtool_ntuple_list.list); 5396 dev->ethtool_ntuple_list.count = 0; 5397 INIT_LIST_HEAD(&dev->napi_list); 5398 INIT_LIST_HEAD(&dev->unreg_list); 5399 INIT_LIST_HEAD(&dev->link_watch_list); 5400 dev->priv_flags = IFF_XMIT_DST_RELEASE; 5401 setup(dev); 5402 strcpy(dev->name, name); 5403 return dev; 5404 5405 free_rx: 5406 #ifdef CONFIG_RPS 5407 kfree(rx); 5408 free_tx: 5409 #endif 5410 kfree(tx); 5411 free_p: 5412 kfree(p); 5413 return NULL; 5414 } 5415 EXPORT_SYMBOL(alloc_netdev_mq); 5416 5417 /** 5418 * free_netdev - free network device 5419 * @dev: device 5420 * 5421 * This function does the last stage of destroying an allocated device 5422 * interface. The reference to the device object is released. 5423 * If this is the last reference then it will be freed. 5424 */ 5425 void free_netdev(struct net_device *dev) 5426 { 5427 struct napi_struct *p, *n; 5428 5429 release_net(dev_net(dev)); 5430 5431 kfree(dev->_tx); 5432 5433 /* Flush device addresses */ 5434 dev_addr_flush(dev); 5435 5436 /* Clear ethtool n-tuple list */ 5437 ethtool_ntuple_flush(dev); 5438 5439 list_for_each_entry_safe(p, n, &dev->napi_list, dev_list) 5440 netif_napi_del(p); 5441 5442 /* Compatibility with error handling in drivers */ 5443 if (dev->reg_state == NETREG_UNINITIALIZED) { 5444 kfree((char *)dev - dev->padded); 5445 return; 5446 } 5447 5448 BUG_ON(dev->reg_state != NETREG_UNREGISTERED); 5449 dev->reg_state = NETREG_RELEASED; 5450 5451 /* will free via device release */ 5452 put_device(&dev->dev); 5453 } 5454 EXPORT_SYMBOL(free_netdev); 5455 5456 /** 5457 * synchronize_net - Synchronize with packet receive processing 5458 * 5459 * Wait for packets currently being received to be done. 5460 * Does not block later packets from starting. 5461 */ 5462 void synchronize_net(void) 5463 { 5464 might_sleep(); 5465 synchronize_rcu(); 5466 } 5467 EXPORT_SYMBOL(synchronize_net); 5468 5469 /** 5470 * unregister_netdevice_queue - remove device from the kernel 5471 * @dev: device 5472 * @head: list 5473 * 5474 * This function shuts down a device interface and removes it 5475 * from the kernel tables. 5476 * If head not NULL, device is queued to be unregistered later. 5477 * 5478 * Callers must hold the rtnl semaphore. You may want 5479 * unregister_netdev() instead of this. 5480 */ 5481 5482 void unregister_netdevice_queue(struct net_device *dev, struct list_head *head) 5483 { 5484 ASSERT_RTNL(); 5485 5486 if (head) { 5487 list_move_tail(&dev->unreg_list, head); 5488 } else { 5489 rollback_registered(dev); 5490 /* Finish processing unregister after unlock */ 5491 net_set_todo(dev); 5492 } 5493 } 5494 EXPORT_SYMBOL(unregister_netdevice_queue); 5495 5496 /** 5497 * unregister_netdevice_many - unregister many devices 5498 * @head: list of devices 5499 */ 5500 void unregister_netdevice_many(struct list_head *head) 5501 { 5502 struct net_device *dev; 5503 5504 if (!list_empty(head)) { 5505 rollback_registered_many(head); 5506 list_for_each_entry(dev, head, unreg_list) 5507 net_set_todo(dev); 5508 } 5509 } 5510 EXPORT_SYMBOL(unregister_netdevice_many); 5511 5512 /** 5513 * unregister_netdev - remove device from the kernel 5514 * @dev: device 5515 * 5516 * This function shuts down a device interface and removes it 5517 * from the kernel tables. 5518 * 5519 * This is just a wrapper for unregister_netdevice that takes 5520 * the rtnl semaphore. In general you want to use this and not 5521 * unregister_netdevice. 5522 */ 5523 void unregister_netdev(struct net_device *dev) 5524 { 5525 rtnl_lock(); 5526 unregister_netdevice(dev); 5527 rtnl_unlock(); 5528 } 5529 EXPORT_SYMBOL(unregister_netdev); 5530 5531 /** 5532 * dev_change_net_namespace - move device to different nethost namespace 5533 * @dev: device 5534 * @net: network namespace 5535 * @pat: If not NULL name pattern to try if the current device name 5536 * is already taken in the destination network namespace. 5537 * 5538 * This function shuts down a device interface and moves it 5539 * to a new network namespace. On success 0 is returned, on 5540 * a failure a netagive errno code is returned. 5541 * 5542 * Callers must hold the rtnl semaphore. 5543 */ 5544 5545 int dev_change_net_namespace(struct net_device *dev, struct net *net, const char *pat) 5546 { 5547 int err; 5548 5549 ASSERT_RTNL(); 5550 5551 /* Don't allow namespace local devices to be moved. */ 5552 err = -EINVAL; 5553 if (dev->features & NETIF_F_NETNS_LOCAL) 5554 goto out; 5555 5556 /* Ensure the device has been registrered */ 5557 err = -EINVAL; 5558 if (dev->reg_state != NETREG_REGISTERED) 5559 goto out; 5560 5561 /* Get out if there is nothing todo */ 5562 err = 0; 5563 if (net_eq(dev_net(dev), net)) 5564 goto out; 5565 5566 /* Pick the destination device name, and ensure 5567 * we can use it in the destination network namespace. 5568 */ 5569 err = -EEXIST; 5570 if (__dev_get_by_name(net, dev->name)) { 5571 /* We get here if we can't use the current device name */ 5572 if (!pat) 5573 goto out; 5574 if (dev_get_valid_name(dev, pat, 1)) 5575 goto out; 5576 } 5577 5578 /* 5579 * And now a mini version of register_netdevice unregister_netdevice. 5580 */ 5581 5582 /* If device is running close it first. */ 5583 dev_close(dev); 5584 5585 /* And unlink it from device chain */ 5586 err = -ENODEV; 5587 unlist_netdevice(dev); 5588 5589 synchronize_net(); 5590 5591 /* Shutdown queueing discipline. */ 5592 dev_shutdown(dev); 5593 5594 /* Notify protocols, that we are about to destroy 5595 this device. They should clean all the things. 5596 */ 5597 call_netdevice_notifiers(NETDEV_UNREGISTER, dev); 5598 call_netdevice_notifiers(NETDEV_UNREGISTER_BATCH, dev); 5599 5600 /* 5601 * Flush the unicast and multicast chains 5602 */ 5603 dev_uc_flush(dev); 5604 dev_mc_flush(dev); 5605 5606 /* Actually switch the network namespace */ 5607 dev_net_set(dev, net); 5608 5609 /* If there is an ifindex conflict assign a new one */ 5610 if (__dev_get_by_index(net, dev->ifindex)) { 5611 int iflink = (dev->iflink == dev->ifindex); 5612 dev->ifindex = dev_new_index(net); 5613 if (iflink) 5614 dev->iflink = dev->ifindex; 5615 } 5616 5617 /* Fixup kobjects */ 5618 err = device_rename(&dev->dev, dev->name); 5619 WARN_ON(err); 5620 5621 /* Add the device back in the hashes */ 5622 list_netdevice(dev); 5623 5624 /* Notify protocols, that a new device appeared. */ 5625 call_netdevice_notifiers(NETDEV_REGISTER, dev); 5626 5627 /* 5628 * Prevent userspace races by waiting until the network 5629 * device is fully setup before sending notifications. 5630 */ 5631 rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U); 5632 5633 synchronize_net(); 5634 err = 0; 5635 out: 5636 return err; 5637 } 5638 EXPORT_SYMBOL_GPL(dev_change_net_namespace); 5639 5640 static int dev_cpu_callback(struct notifier_block *nfb, 5641 unsigned long action, 5642 void *ocpu) 5643 { 5644 struct sk_buff **list_skb; 5645 struct sk_buff *skb; 5646 unsigned int cpu, oldcpu = (unsigned long)ocpu; 5647 struct softnet_data *sd, *oldsd; 5648 5649 if (action != CPU_DEAD && action != CPU_DEAD_FROZEN) 5650 return NOTIFY_OK; 5651 5652 local_irq_disable(); 5653 cpu = smp_processor_id(); 5654 sd = &per_cpu(softnet_data, cpu); 5655 oldsd = &per_cpu(softnet_data, oldcpu); 5656 5657 /* Find end of our completion_queue. */ 5658 list_skb = &sd->completion_queue; 5659 while (*list_skb) 5660 list_skb = &(*list_skb)->next; 5661 /* Append completion queue from offline CPU. */ 5662 *list_skb = oldsd->completion_queue; 5663 oldsd->completion_queue = NULL; 5664 5665 /* Append output queue from offline CPU. */ 5666 if (oldsd->output_queue) { 5667 *sd->output_queue_tailp = oldsd->output_queue; 5668 sd->output_queue_tailp = oldsd->output_queue_tailp; 5669 oldsd->output_queue = NULL; 5670 oldsd->output_queue_tailp = &oldsd->output_queue; 5671 } 5672 5673 raise_softirq_irqoff(NET_TX_SOFTIRQ); 5674 local_irq_enable(); 5675 5676 /* Process offline CPU's input_pkt_queue */ 5677 while ((skb = __skb_dequeue(&oldsd->process_queue))) { 5678 netif_rx(skb); 5679 input_queue_head_incr(oldsd); 5680 } 5681 while ((skb = __skb_dequeue(&oldsd->input_pkt_queue))) { 5682 netif_rx(skb); 5683 input_queue_head_incr(oldsd); 5684 } 5685 5686 return NOTIFY_OK; 5687 } 5688 5689 5690 /** 5691 * netdev_increment_features - increment feature set by one 5692 * @all: current feature set 5693 * @one: new feature set 5694 * @mask: mask feature set 5695 * 5696 * Computes a new feature set after adding a device with feature set 5697 * @one to the master device with current feature set @all. Will not 5698 * enable anything that is off in @mask. Returns the new feature set. 5699 */ 5700 unsigned long netdev_increment_features(unsigned long all, unsigned long one, 5701 unsigned long mask) 5702 { 5703 /* If device needs checksumming, downgrade to it. */ 5704 if (all & NETIF_F_NO_CSUM && !(one & NETIF_F_NO_CSUM)) 5705 all ^= NETIF_F_NO_CSUM | (one & NETIF_F_ALL_CSUM); 5706 else if (mask & NETIF_F_ALL_CSUM) { 5707 /* If one device supports v4/v6 checksumming, set for all. */ 5708 if (one & (NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM) && 5709 !(all & NETIF_F_GEN_CSUM)) { 5710 all &= ~NETIF_F_ALL_CSUM; 5711 all |= one & (NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM); 5712 } 5713 5714 /* If one device supports hw checksumming, set for all. */ 5715 if (one & NETIF_F_GEN_CSUM && !(all & NETIF_F_GEN_CSUM)) { 5716 all &= ~NETIF_F_ALL_CSUM; 5717 all |= NETIF_F_HW_CSUM; 5718 } 5719 } 5720 5721 one |= NETIF_F_ALL_CSUM; 5722 5723 one |= all & NETIF_F_ONE_FOR_ALL; 5724 all &= one | NETIF_F_LLTX | NETIF_F_GSO | NETIF_F_UFO; 5725 all |= one & mask & NETIF_F_ONE_FOR_ALL; 5726 5727 return all; 5728 } 5729 EXPORT_SYMBOL(netdev_increment_features); 5730 5731 static struct hlist_head *netdev_create_hash(void) 5732 { 5733 int i; 5734 struct hlist_head *hash; 5735 5736 hash = kmalloc(sizeof(*hash) * NETDEV_HASHENTRIES, GFP_KERNEL); 5737 if (hash != NULL) 5738 for (i = 0; i < NETDEV_HASHENTRIES; i++) 5739 INIT_HLIST_HEAD(&hash[i]); 5740 5741 return hash; 5742 } 5743 5744 /* Initialize per network namespace state */ 5745 static int __net_init netdev_init(struct net *net) 5746 { 5747 INIT_LIST_HEAD(&net->dev_base_head); 5748 5749 net->dev_name_head = netdev_create_hash(); 5750 if (net->dev_name_head == NULL) 5751 goto err_name; 5752 5753 net->dev_index_head = netdev_create_hash(); 5754 if (net->dev_index_head == NULL) 5755 goto err_idx; 5756 5757 return 0; 5758 5759 err_idx: 5760 kfree(net->dev_name_head); 5761 err_name: 5762 return -ENOMEM; 5763 } 5764 5765 /** 5766 * netdev_drivername - network driver for the device 5767 * @dev: network device 5768 * @buffer: buffer for resulting name 5769 * @len: size of buffer 5770 * 5771 * Determine network driver for device. 5772 */ 5773 char *netdev_drivername(const struct net_device *dev, char *buffer, int len) 5774 { 5775 const struct device_driver *driver; 5776 const struct device *parent; 5777 5778 if (len <= 0 || !buffer) 5779 return buffer; 5780 buffer[0] = 0; 5781 5782 parent = dev->dev.parent; 5783 5784 if (!parent) 5785 return buffer; 5786 5787 driver = parent->driver; 5788 if (driver && driver->name) 5789 strlcpy(buffer, driver->name, len); 5790 return buffer; 5791 } 5792 5793 static void __net_exit netdev_exit(struct net *net) 5794 { 5795 kfree(net->dev_name_head); 5796 kfree(net->dev_index_head); 5797 } 5798 5799 static struct pernet_operations __net_initdata netdev_net_ops = { 5800 .init = netdev_init, 5801 .exit = netdev_exit, 5802 }; 5803 5804 static void __net_exit default_device_exit(struct net *net) 5805 { 5806 struct net_device *dev, *aux; 5807 /* 5808 * Push all migratable network devices back to the 5809 * initial network namespace 5810 */ 5811 rtnl_lock(); 5812 for_each_netdev_safe(net, dev, aux) { 5813 int err; 5814 char fb_name[IFNAMSIZ]; 5815 5816 /* Ignore unmoveable devices (i.e. loopback) */ 5817 if (dev->features & NETIF_F_NETNS_LOCAL) 5818 continue; 5819 5820 /* Leave virtual devices for the generic cleanup */ 5821 if (dev->rtnl_link_ops) 5822 continue; 5823 5824 /* Push remaing network devices to init_net */ 5825 snprintf(fb_name, IFNAMSIZ, "dev%d", dev->ifindex); 5826 err = dev_change_net_namespace(dev, &init_net, fb_name); 5827 if (err) { 5828 printk(KERN_EMERG "%s: failed to move %s to init_net: %d\n", 5829 __func__, dev->name, err); 5830 BUG(); 5831 } 5832 } 5833 rtnl_unlock(); 5834 } 5835 5836 static void __net_exit default_device_exit_batch(struct list_head *net_list) 5837 { 5838 /* At exit all network devices most be removed from a network 5839 * namespace. Do this in the reverse order of registeration. 5840 * Do this across as many network namespaces as possible to 5841 * improve batching efficiency. 5842 */ 5843 struct net_device *dev; 5844 struct net *net; 5845 LIST_HEAD(dev_kill_list); 5846 5847 rtnl_lock(); 5848 list_for_each_entry(net, net_list, exit_list) { 5849 for_each_netdev_reverse(net, dev) { 5850 if (dev->rtnl_link_ops) 5851 dev->rtnl_link_ops->dellink(dev, &dev_kill_list); 5852 else 5853 unregister_netdevice_queue(dev, &dev_kill_list); 5854 } 5855 } 5856 unregister_netdevice_many(&dev_kill_list); 5857 rtnl_unlock(); 5858 } 5859 5860 static struct pernet_operations __net_initdata default_device_ops = { 5861 .exit = default_device_exit, 5862 .exit_batch = default_device_exit_batch, 5863 }; 5864 5865 /* 5866 * Initialize the DEV module. At boot time this walks the device list and 5867 * unhooks any devices that fail to initialise (normally hardware not 5868 * present) and leaves us with a valid list of present and active devices. 5869 * 5870 */ 5871 5872 /* 5873 * This is called single threaded during boot, so no need 5874 * to take the rtnl semaphore. 5875 */ 5876 static int __init net_dev_init(void) 5877 { 5878 int i, rc = -ENOMEM; 5879 5880 BUG_ON(!dev_boot_phase); 5881 5882 if (dev_proc_init()) 5883 goto out; 5884 5885 if (netdev_kobject_init()) 5886 goto out; 5887 5888 INIT_LIST_HEAD(&ptype_all); 5889 for (i = 0; i < PTYPE_HASH_SIZE; i++) 5890 INIT_LIST_HEAD(&ptype_base[i]); 5891 5892 if (register_pernet_subsys(&netdev_net_ops)) 5893 goto out; 5894 5895 /* 5896 * Initialise the packet receive queues. 5897 */ 5898 5899 for_each_possible_cpu(i) { 5900 struct softnet_data *sd = &per_cpu(softnet_data, i); 5901 5902 memset(sd, 0, sizeof(*sd)); 5903 skb_queue_head_init(&sd->input_pkt_queue); 5904 skb_queue_head_init(&sd->process_queue); 5905 sd->completion_queue = NULL; 5906 INIT_LIST_HEAD(&sd->poll_list); 5907 sd->output_queue = NULL; 5908 sd->output_queue_tailp = &sd->output_queue; 5909 #ifdef CONFIG_RPS 5910 sd->csd.func = rps_trigger_softirq; 5911 sd->csd.info = sd; 5912 sd->csd.flags = 0; 5913 sd->cpu = i; 5914 #endif 5915 5916 sd->backlog.poll = process_backlog; 5917 sd->backlog.weight = weight_p; 5918 sd->backlog.gro_list = NULL; 5919 sd->backlog.gro_count = 0; 5920 } 5921 5922 dev_boot_phase = 0; 5923 5924 /* The loopback device is special if any other network devices 5925 * is present in a network namespace the loopback device must 5926 * be present. Since we now dynamically allocate and free the 5927 * loopback device ensure this invariant is maintained by 5928 * keeping the loopback device as the first device on the 5929 * list of network devices. Ensuring the loopback devices 5930 * is the first device that appears and the last network device 5931 * that disappears. 5932 */ 5933 if (register_pernet_device(&loopback_net_ops)) 5934 goto out; 5935 5936 if (register_pernet_device(&default_device_ops)) 5937 goto out; 5938 5939 open_softirq(NET_TX_SOFTIRQ, net_tx_action); 5940 open_softirq(NET_RX_SOFTIRQ, net_rx_action); 5941 5942 hotcpu_notifier(dev_cpu_callback, 0); 5943 dst_init(); 5944 dev_mcast_init(); 5945 rc = 0; 5946 out: 5947 return rc; 5948 } 5949 5950 subsys_initcall(net_dev_init); 5951 5952 static int __init initialize_hashrnd(void) 5953 { 5954 get_random_bytes(&hashrnd, sizeof(hashrnd)); 5955 return 0; 5956 } 5957 5958 late_initcall_sync(initialize_hashrnd); 5959 5960