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/sched.h> 83 #include <linux/mutex.h> 84 #include <linux/string.h> 85 #include <linux/mm.h> 86 #include <linux/socket.h> 87 #include <linux/sockios.h> 88 #include <linux/errno.h> 89 #include <linux/interrupt.h> 90 #include <linux/if_ether.h> 91 #include <linux/netdevice.h> 92 #include <linux/etherdevice.h> 93 #include <linux/notifier.h> 94 #include <linux/skbuff.h> 95 #include <net/sock.h> 96 #include <linux/rtnetlink.h> 97 #include <linux/proc_fs.h> 98 #include <linux/seq_file.h> 99 #include <linux/stat.h> 100 #include <linux/if_bridge.h> 101 #include <net/dst.h> 102 #include <net/pkt_sched.h> 103 #include <net/checksum.h> 104 #include <linux/highmem.h> 105 #include <linux/init.h> 106 #include <linux/kmod.h> 107 #include <linux/module.h> 108 #include <linux/kallsyms.h> 109 #include <linux/netpoll.h> 110 #include <linux/rcupdate.h> 111 #include <linux/delay.h> 112 #include <linux/wireless.h> 113 #include <net/iw_handler.h> 114 #include <asm/current.h> 115 #include <linux/audit.h> 116 #include <linux/dmaengine.h> 117 #include <linux/err.h> 118 #include <linux/ctype.h> 119 120 /* 121 * The list of packet types we will receive (as opposed to discard) 122 * and the routines to invoke. 123 * 124 * Why 16. Because with 16 the only overlap we get on a hash of the 125 * low nibble of the protocol value is RARP/SNAP/X.25. 126 * 127 * NOTE: That is no longer true with the addition of VLAN tags. Not 128 * sure which should go first, but I bet it won't make much 129 * difference if we are running VLANs. The good news is that 130 * this protocol won't be in the list unless compiled in, so 131 * the average user (w/out VLANs) will not be adversely affected. 132 * --BLG 133 * 134 * 0800 IP 135 * 8100 802.1Q VLAN 136 * 0001 802.3 137 * 0002 AX.25 138 * 0004 802.2 139 * 8035 RARP 140 * 0005 SNAP 141 * 0805 X.25 142 * 0806 ARP 143 * 8137 IPX 144 * 0009 Localtalk 145 * 86DD IPv6 146 */ 147 148 static DEFINE_SPINLOCK(ptype_lock); 149 static struct list_head ptype_base[16]; /* 16 way hashed list */ 150 static struct list_head ptype_all; /* Taps */ 151 152 #ifdef CONFIG_NET_DMA 153 static struct dma_client *net_dma_client; 154 static unsigned int net_dma_count; 155 static spinlock_t net_dma_event_lock; 156 #endif 157 158 /* 159 * The @dev_base list is protected by @dev_base_lock and the rtnl 160 * semaphore. 161 * 162 * Pure readers hold dev_base_lock for reading. 163 * 164 * Writers must hold the rtnl semaphore while they loop through the 165 * dev_base list, and hold dev_base_lock for writing when they do the 166 * actual updates. This allows pure readers to access the list even 167 * while a writer is preparing to update it. 168 * 169 * To put it another way, dev_base_lock is held for writing only to 170 * protect against pure readers; the rtnl semaphore provides the 171 * protection against other writers. 172 * 173 * See, for example usages, register_netdevice() and 174 * unregister_netdevice(), which must be called with the rtnl 175 * semaphore held. 176 */ 177 struct net_device *dev_base; 178 static struct net_device **dev_tail = &dev_base; 179 DEFINE_RWLOCK(dev_base_lock); 180 181 EXPORT_SYMBOL(dev_base); 182 EXPORT_SYMBOL(dev_base_lock); 183 184 #define NETDEV_HASHBITS 8 185 static struct hlist_head dev_name_head[1<<NETDEV_HASHBITS]; 186 static struct hlist_head dev_index_head[1<<NETDEV_HASHBITS]; 187 188 static inline struct hlist_head *dev_name_hash(const char *name) 189 { 190 unsigned hash = full_name_hash(name, strnlen(name, IFNAMSIZ)); 191 return &dev_name_head[hash & ((1<<NETDEV_HASHBITS)-1)]; 192 } 193 194 static inline struct hlist_head *dev_index_hash(int ifindex) 195 { 196 return &dev_index_head[ifindex & ((1<<NETDEV_HASHBITS)-1)]; 197 } 198 199 /* 200 * Our notifier list 201 */ 202 203 static RAW_NOTIFIER_HEAD(netdev_chain); 204 205 /* 206 * Device drivers call our routines to queue packets here. We empty the 207 * queue in the local softnet handler. 208 */ 209 DEFINE_PER_CPU(struct softnet_data, softnet_data) = { NULL }; 210 211 #ifdef CONFIG_SYSFS 212 extern int netdev_sysfs_init(void); 213 extern int netdev_register_sysfs(struct net_device *); 214 extern void netdev_unregister_sysfs(struct net_device *); 215 #else 216 #define netdev_sysfs_init() (0) 217 #define netdev_register_sysfs(dev) (0) 218 #define netdev_unregister_sysfs(dev) do { } while(0) 219 #endif 220 221 222 /******************************************************************************* 223 224 Protocol management and registration routines 225 226 *******************************************************************************/ 227 228 /* 229 * For efficiency 230 */ 231 232 static int netdev_nit; 233 234 /* 235 * Add a protocol ID to the list. Now that the input handler is 236 * smarter we can dispense with all the messy stuff that used to be 237 * here. 238 * 239 * BEWARE!!! Protocol handlers, mangling input packets, 240 * MUST BE last in hash buckets and checking protocol handlers 241 * MUST start from promiscuous ptype_all chain in net_bh. 242 * It is true now, do not change it. 243 * Explanation follows: if protocol handler, mangling packet, will 244 * be the first on list, it is not able to sense, that packet 245 * is cloned and should be copied-on-write, so that it will 246 * change it and subsequent readers will get broken packet. 247 * --ANK (980803) 248 */ 249 250 /** 251 * dev_add_pack - add packet handler 252 * @pt: packet type declaration 253 * 254 * Add a protocol handler to the networking stack. The passed &packet_type 255 * is linked into kernel lists and may not be freed until it has been 256 * removed from the kernel lists. 257 * 258 * This call does not sleep therefore it can not 259 * guarantee all CPU's that are in middle of receiving packets 260 * will see the new packet type (until the next received packet). 261 */ 262 263 void dev_add_pack(struct packet_type *pt) 264 { 265 int hash; 266 267 spin_lock_bh(&ptype_lock); 268 if (pt->type == htons(ETH_P_ALL)) { 269 netdev_nit++; 270 list_add_rcu(&pt->list, &ptype_all); 271 } else { 272 hash = ntohs(pt->type) & 15; 273 list_add_rcu(&pt->list, &ptype_base[hash]); 274 } 275 spin_unlock_bh(&ptype_lock); 276 } 277 278 /** 279 * __dev_remove_pack - remove packet handler 280 * @pt: packet type declaration 281 * 282 * Remove a protocol handler that was previously added to the kernel 283 * protocol handlers by dev_add_pack(). The passed &packet_type is removed 284 * from the kernel lists and can be freed or reused once this function 285 * returns. 286 * 287 * The packet type might still be in use by receivers 288 * and must not be freed until after all the CPU's have gone 289 * through a quiescent state. 290 */ 291 void __dev_remove_pack(struct packet_type *pt) 292 { 293 struct list_head *head; 294 struct packet_type *pt1; 295 296 spin_lock_bh(&ptype_lock); 297 298 if (pt->type == htons(ETH_P_ALL)) { 299 netdev_nit--; 300 head = &ptype_all; 301 } else 302 head = &ptype_base[ntohs(pt->type) & 15]; 303 304 list_for_each_entry(pt1, head, list) { 305 if (pt == pt1) { 306 list_del_rcu(&pt->list); 307 goto out; 308 } 309 } 310 311 printk(KERN_WARNING "dev_remove_pack: %p not found.\n", pt); 312 out: 313 spin_unlock_bh(&ptype_lock); 314 } 315 /** 316 * dev_remove_pack - remove packet handler 317 * @pt: packet type declaration 318 * 319 * Remove a protocol handler that was previously added to the kernel 320 * protocol handlers by dev_add_pack(). The passed &packet_type is removed 321 * from the kernel lists and can be freed or reused once this function 322 * returns. 323 * 324 * This call sleeps to guarantee that no CPU is looking at the packet 325 * type after return. 326 */ 327 void dev_remove_pack(struct packet_type *pt) 328 { 329 __dev_remove_pack(pt); 330 331 synchronize_net(); 332 } 333 334 /****************************************************************************** 335 336 Device Boot-time Settings Routines 337 338 *******************************************************************************/ 339 340 /* Boot time configuration table */ 341 static struct netdev_boot_setup dev_boot_setup[NETDEV_BOOT_SETUP_MAX]; 342 343 /** 344 * netdev_boot_setup_add - add new setup entry 345 * @name: name of the device 346 * @map: configured settings for the device 347 * 348 * Adds new setup entry to the dev_boot_setup list. The function 349 * returns 0 on error and 1 on success. This is a generic routine to 350 * all netdevices. 351 */ 352 static int netdev_boot_setup_add(char *name, struct ifmap *map) 353 { 354 struct netdev_boot_setup *s; 355 int i; 356 357 s = dev_boot_setup; 358 for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++) { 359 if (s[i].name[0] == '\0' || s[i].name[0] == ' ') { 360 memset(s[i].name, 0, sizeof(s[i].name)); 361 strcpy(s[i].name, name); 362 memcpy(&s[i].map, map, sizeof(s[i].map)); 363 break; 364 } 365 } 366 367 return i >= NETDEV_BOOT_SETUP_MAX ? 0 : 1; 368 } 369 370 /** 371 * netdev_boot_setup_check - check boot time settings 372 * @dev: the netdevice 373 * 374 * Check boot time settings for the device. 375 * The found settings are set for the device to be used 376 * later in the device probing. 377 * Returns 0 if no settings found, 1 if they are. 378 */ 379 int netdev_boot_setup_check(struct net_device *dev) 380 { 381 struct netdev_boot_setup *s = dev_boot_setup; 382 int i; 383 384 for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++) { 385 if (s[i].name[0] != '\0' && s[i].name[0] != ' ' && 386 !strncmp(dev->name, s[i].name, strlen(s[i].name))) { 387 dev->irq = s[i].map.irq; 388 dev->base_addr = s[i].map.base_addr; 389 dev->mem_start = s[i].map.mem_start; 390 dev->mem_end = s[i].map.mem_end; 391 return 1; 392 } 393 } 394 return 0; 395 } 396 397 398 /** 399 * netdev_boot_base - get address from boot time settings 400 * @prefix: prefix for network device 401 * @unit: id for network device 402 * 403 * Check boot time settings for the base address of device. 404 * The found settings are set for the device to be used 405 * later in the device probing. 406 * Returns 0 if no settings found. 407 */ 408 unsigned long netdev_boot_base(const char *prefix, int unit) 409 { 410 const struct netdev_boot_setup *s = dev_boot_setup; 411 char name[IFNAMSIZ]; 412 int i; 413 414 sprintf(name, "%s%d", prefix, unit); 415 416 /* 417 * If device already registered then return base of 1 418 * to indicate not to probe for this interface 419 */ 420 if (__dev_get_by_name(name)) 421 return 1; 422 423 for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++) 424 if (!strcmp(name, s[i].name)) 425 return s[i].map.base_addr; 426 return 0; 427 } 428 429 /* 430 * Saves at boot time configured settings for any netdevice. 431 */ 432 int __init netdev_boot_setup(char *str) 433 { 434 int ints[5]; 435 struct ifmap map; 436 437 str = get_options(str, ARRAY_SIZE(ints), ints); 438 if (!str || !*str) 439 return 0; 440 441 /* Save settings */ 442 memset(&map, 0, sizeof(map)); 443 if (ints[0] > 0) 444 map.irq = ints[1]; 445 if (ints[0] > 1) 446 map.base_addr = ints[2]; 447 if (ints[0] > 2) 448 map.mem_start = ints[3]; 449 if (ints[0] > 3) 450 map.mem_end = ints[4]; 451 452 /* Add new entry to the list */ 453 return netdev_boot_setup_add(str, &map); 454 } 455 456 __setup("netdev=", netdev_boot_setup); 457 458 /******************************************************************************* 459 460 Device Interface Subroutines 461 462 *******************************************************************************/ 463 464 /** 465 * __dev_get_by_name - find a device by its name 466 * @name: name to find 467 * 468 * Find an interface by name. Must be called under RTNL semaphore 469 * or @dev_base_lock. If the name is found a pointer to the device 470 * is returned. If the name is not found then %NULL is returned. The 471 * reference counters are not incremented so the caller must be 472 * careful with locks. 473 */ 474 475 struct net_device *__dev_get_by_name(const char *name) 476 { 477 struct hlist_node *p; 478 479 hlist_for_each(p, dev_name_hash(name)) { 480 struct net_device *dev 481 = hlist_entry(p, struct net_device, name_hlist); 482 if (!strncmp(dev->name, name, IFNAMSIZ)) 483 return dev; 484 } 485 return NULL; 486 } 487 488 /** 489 * dev_get_by_name - find a device by its name 490 * @name: name to find 491 * 492 * Find an interface by name. This can be called from any 493 * context and does its own locking. The returned handle has 494 * the usage count incremented and the caller must use dev_put() to 495 * release it when it is no longer needed. %NULL is returned if no 496 * matching device is found. 497 */ 498 499 struct net_device *dev_get_by_name(const char *name) 500 { 501 struct net_device *dev; 502 503 read_lock(&dev_base_lock); 504 dev = __dev_get_by_name(name); 505 if (dev) 506 dev_hold(dev); 507 read_unlock(&dev_base_lock); 508 return dev; 509 } 510 511 /** 512 * __dev_get_by_index - find a device by its ifindex 513 * @ifindex: index of device 514 * 515 * Search for an interface by index. Returns %NULL if the device 516 * is not found or a pointer to the device. The device has not 517 * had its reference counter increased so the caller must be careful 518 * about locking. The caller must hold either the RTNL semaphore 519 * or @dev_base_lock. 520 */ 521 522 struct net_device *__dev_get_by_index(int ifindex) 523 { 524 struct hlist_node *p; 525 526 hlist_for_each(p, dev_index_hash(ifindex)) { 527 struct net_device *dev 528 = hlist_entry(p, struct net_device, index_hlist); 529 if (dev->ifindex == ifindex) 530 return dev; 531 } 532 return NULL; 533 } 534 535 536 /** 537 * dev_get_by_index - find a device by its ifindex 538 * @ifindex: index of device 539 * 540 * Search for an interface by index. Returns NULL if the device 541 * is not found or a pointer to the device. The device returned has 542 * had a reference added and the pointer is safe until the user calls 543 * dev_put to indicate they have finished with it. 544 */ 545 546 struct net_device *dev_get_by_index(int ifindex) 547 { 548 struct net_device *dev; 549 550 read_lock(&dev_base_lock); 551 dev = __dev_get_by_index(ifindex); 552 if (dev) 553 dev_hold(dev); 554 read_unlock(&dev_base_lock); 555 return dev; 556 } 557 558 /** 559 * dev_getbyhwaddr - find a device by its hardware address 560 * @type: media type of device 561 * @ha: hardware address 562 * 563 * Search for an interface by MAC address. Returns NULL if the device 564 * is not found or a pointer to the device. The caller must hold the 565 * rtnl semaphore. The returned device has not had its ref count increased 566 * and the caller must therefore be careful about locking 567 * 568 * BUGS: 569 * If the API was consistent this would be __dev_get_by_hwaddr 570 */ 571 572 struct net_device *dev_getbyhwaddr(unsigned short type, char *ha) 573 { 574 struct net_device *dev; 575 576 ASSERT_RTNL(); 577 578 for (dev = dev_base; dev; dev = dev->next) 579 if (dev->type == type && 580 !memcmp(dev->dev_addr, ha, dev->addr_len)) 581 break; 582 return dev; 583 } 584 585 EXPORT_SYMBOL(dev_getbyhwaddr); 586 587 struct net_device *dev_getfirstbyhwtype(unsigned short type) 588 { 589 struct net_device *dev; 590 591 rtnl_lock(); 592 for (dev = dev_base; dev; dev = dev->next) { 593 if (dev->type == type) { 594 dev_hold(dev); 595 break; 596 } 597 } 598 rtnl_unlock(); 599 return dev; 600 } 601 602 EXPORT_SYMBOL(dev_getfirstbyhwtype); 603 604 /** 605 * dev_get_by_flags - find any device with given flags 606 * @if_flags: IFF_* values 607 * @mask: bitmask of bits in if_flags to check 608 * 609 * Search for any interface with the given flags. Returns NULL if a device 610 * is not found or a pointer to the device. The device returned has 611 * had a reference added and the pointer is safe until the user calls 612 * dev_put to indicate they have finished with it. 613 */ 614 615 struct net_device * dev_get_by_flags(unsigned short if_flags, unsigned short mask) 616 { 617 struct net_device *dev; 618 619 read_lock(&dev_base_lock); 620 for (dev = dev_base; dev != NULL; dev = dev->next) { 621 if (((dev->flags ^ if_flags) & mask) == 0) { 622 dev_hold(dev); 623 break; 624 } 625 } 626 read_unlock(&dev_base_lock); 627 return dev; 628 } 629 630 /** 631 * dev_valid_name - check if name is okay for network device 632 * @name: name string 633 * 634 * Network device names need to be valid file names to 635 * to allow sysfs to work. We also disallow any kind of 636 * whitespace. 637 */ 638 int dev_valid_name(const char *name) 639 { 640 if (*name == '\0') 641 return 0; 642 if (strlen(name) >= IFNAMSIZ) 643 return 0; 644 if (!strcmp(name, ".") || !strcmp(name, "..")) 645 return 0; 646 647 while (*name) { 648 if (*name == '/' || isspace(*name)) 649 return 0; 650 name++; 651 } 652 return 1; 653 } 654 655 /** 656 * dev_alloc_name - allocate a name for a device 657 * @dev: device 658 * @name: name format string 659 * 660 * Passed a format string - eg "lt%d" it will try and find a suitable 661 * id. It scans list of devices to build up a free map, then chooses 662 * the first empty slot. The caller must hold the dev_base or rtnl lock 663 * while allocating the name and adding the device in order to avoid 664 * duplicates. 665 * Limited to bits_per_byte * page size devices (ie 32K on most platforms). 666 * Returns the number of the unit assigned or a negative errno code. 667 */ 668 669 int dev_alloc_name(struct net_device *dev, const char *name) 670 { 671 int i = 0; 672 char buf[IFNAMSIZ]; 673 const char *p; 674 const int max_netdevices = 8*PAGE_SIZE; 675 long *inuse; 676 struct net_device *d; 677 678 p = strnchr(name, IFNAMSIZ-1, '%'); 679 if (p) { 680 /* 681 * Verify the string as this thing may have come from 682 * the user. There must be either one "%d" and no other "%" 683 * characters. 684 */ 685 if (p[1] != 'd' || strchr(p + 2, '%')) 686 return -EINVAL; 687 688 /* Use one page as a bit array of possible slots */ 689 inuse = (long *) get_zeroed_page(GFP_ATOMIC); 690 if (!inuse) 691 return -ENOMEM; 692 693 for (d = dev_base; d; d = d->next) { 694 if (!sscanf(d->name, name, &i)) 695 continue; 696 if (i < 0 || i >= max_netdevices) 697 continue; 698 699 /* avoid cases where sscanf is not exact inverse of printf */ 700 snprintf(buf, sizeof(buf), name, i); 701 if (!strncmp(buf, d->name, IFNAMSIZ)) 702 set_bit(i, inuse); 703 } 704 705 i = find_first_zero_bit(inuse, max_netdevices); 706 free_page((unsigned long) inuse); 707 } 708 709 snprintf(buf, sizeof(buf), name, i); 710 if (!__dev_get_by_name(buf)) { 711 strlcpy(dev->name, buf, IFNAMSIZ); 712 return i; 713 } 714 715 /* It is possible to run out of possible slots 716 * when the name is long and there isn't enough space left 717 * for the digits, or if all bits are used. 718 */ 719 return -ENFILE; 720 } 721 722 723 /** 724 * dev_change_name - change name of a device 725 * @dev: device 726 * @newname: name (or format string) must be at least IFNAMSIZ 727 * 728 * Change name of a device, can pass format strings "eth%d". 729 * for wildcarding. 730 */ 731 int dev_change_name(struct net_device *dev, char *newname) 732 { 733 int err = 0; 734 735 ASSERT_RTNL(); 736 737 if (dev->flags & IFF_UP) 738 return -EBUSY; 739 740 if (!dev_valid_name(newname)) 741 return -EINVAL; 742 743 if (strchr(newname, '%')) { 744 err = dev_alloc_name(dev, newname); 745 if (err < 0) 746 return err; 747 strcpy(newname, dev->name); 748 } 749 else if (__dev_get_by_name(newname)) 750 return -EEXIST; 751 else 752 strlcpy(dev->name, newname, IFNAMSIZ); 753 754 err = device_rename(&dev->dev, dev->name); 755 if (!err) { 756 hlist_del(&dev->name_hlist); 757 hlist_add_head(&dev->name_hlist, dev_name_hash(dev->name)); 758 raw_notifier_call_chain(&netdev_chain, 759 NETDEV_CHANGENAME, dev); 760 } 761 762 return err; 763 } 764 765 /** 766 * netdev_features_change - device changes features 767 * @dev: device to cause notification 768 * 769 * Called to indicate a device has changed features. 770 */ 771 void netdev_features_change(struct net_device *dev) 772 { 773 raw_notifier_call_chain(&netdev_chain, NETDEV_FEAT_CHANGE, dev); 774 } 775 EXPORT_SYMBOL(netdev_features_change); 776 777 /** 778 * netdev_state_change - device changes state 779 * @dev: device to cause notification 780 * 781 * Called to indicate a device has changed state. This function calls 782 * the notifier chains for netdev_chain and sends a NEWLINK message 783 * to the routing socket. 784 */ 785 void netdev_state_change(struct net_device *dev) 786 { 787 if (dev->flags & IFF_UP) { 788 raw_notifier_call_chain(&netdev_chain, 789 NETDEV_CHANGE, dev); 790 rtmsg_ifinfo(RTM_NEWLINK, dev, 0); 791 } 792 } 793 794 /** 795 * dev_load - load a network module 796 * @name: name of interface 797 * 798 * If a network interface is not present and the process has suitable 799 * privileges this function loads the module. If module loading is not 800 * available in this kernel then it becomes a nop. 801 */ 802 803 void dev_load(const char *name) 804 { 805 struct net_device *dev; 806 807 read_lock(&dev_base_lock); 808 dev = __dev_get_by_name(name); 809 read_unlock(&dev_base_lock); 810 811 if (!dev && capable(CAP_SYS_MODULE)) 812 request_module("%s", name); 813 } 814 815 static int default_rebuild_header(struct sk_buff *skb) 816 { 817 printk(KERN_DEBUG "%s: default_rebuild_header called -- BUG!\n", 818 skb->dev ? skb->dev->name : "NULL!!!"); 819 kfree_skb(skb); 820 return 1; 821 } 822 823 824 /** 825 * dev_open - prepare an interface for use. 826 * @dev: device to open 827 * 828 * Takes a device from down to up state. The device's private open 829 * function is invoked and then the multicast lists are loaded. Finally 830 * the device is moved into the up state and a %NETDEV_UP message is 831 * sent to the netdev notifier chain. 832 * 833 * Calling this function on an active interface is a nop. On a failure 834 * a negative errno code is returned. 835 */ 836 int dev_open(struct net_device *dev) 837 { 838 int ret = 0; 839 840 /* 841 * Is it already up? 842 */ 843 844 if (dev->flags & IFF_UP) 845 return 0; 846 847 /* 848 * Is it even present? 849 */ 850 if (!netif_device_present(dev)) 851 return -ENODEV; 852 853 /* 854 * Call device private open method 855 */ 856 set_bit(__LINK_STATE_START, &dev->state); 857 if (dev->open) { 858 ret = dev->open(dev); 859 if (ret) 860 clear_bit(__LINK_STATE_START, &dev->state); 861 } 862 863 /* 864 * If it went open OK then: 865 */ 866 867 if (!ret) { 868 /* 869 * Set the flags. 870 */ 871 dev->flags |= IFF_UP; 872 873 /* 874 * Initialize multicasting status 875 */ 876 dev_mc_upload(dev); 877 878 /* 879 * Wakeup transmit queue engine 880 */ 881 dev_activate(dev); 882 883 /* 884 * ... and announce new interface. 885 */ 886 raw_notifier_call_chain(&netdev_chain, NETDEV_UP, dev); 887 } 888 return ret; 889 } 890 891 /** 892 * dev_close - shutdown an interface. 893 * @dev: device to shutdown 894 * 895 * This function moves an active device into down state. A 896 * %NETDEV_GOING_DOWN is sent to the netdev notifier chain. The device 897 * is then deactivated and finally a %NETDEV_DOWN is sent to the notifier 898 * chain. 899 */ 900 int dev_close(struct net_device *dev) 901 { 902 if (!(dev->flags & IFF_UP)) 903 return 0; 904 905 /* 906 * Tell people we are going down, so that they can 907 * prepare to death, when device is still operating. 908 */ 909 raw_notifier_call_chain(&netdev_chain, NETDEV_GOING_DOWN, dev); 910 911 dev_deactivate(dev); 912 913 clear_bit(__LINK_STATE_START, &dev->state); 914 915 /* Synchronize to scheduled poll. We cannot touch poll list, 916 * it can be even on different cpu. So just clear netif_running(), 917 * and wait when poll really will happen. Actually, the best place 918 * for this is inside dev->stop() after device stopped its irq 919 * engine, but this requires more changes in devices. */ 920 921 smp_mb__after_clear_bit(); /* Commit netif_running(). */ 922 while (test_bit(__LINK_STATE_RX_SCHED, &dev->state)) { 923 /* No hurry. */ 924 msleep(1); 925 } 926 927 /* 928 * Call the device specific close. This cannot fail. 929 * Only if device is UP 930 * 931 * We allow it to be called even after a DETACH hot-plug 932 * event. 933 */ 934 if (dev->stop) 935 dev->stop(dev); 936 937 /* 938 * Device is now down. 939 */ 940 941 dev->flags &= ~IFF_UP; 942 943 /* 944 * Tell people we are down 945 */ 946 raw_notifier_call_chain(&netdev_chain, NETDEV_DOWN, dev); 947 948 return 0; 949 } 950 951 952 /* 953 * Device change register/unregister. These are not inline or static 954 * as we export them to the world. 955 */ 956 957 /** 958 * register_netdevice_notifier - register a network notifier block 959 * @nb: notifier 960 * 961 * Register a notifier to be called when network device events occur. 962 * The notifier passed is linked into the kernel structures and must 963 * not be reused until it has been unregistered. A negative errno code 964 * is returned on a failure. 965 * 966 * When registered all registration and up events are replayed 967 * to the new notifier to allow device to have a race free 968 * view of the network device list. 969 */ 970 971 int register_netdevice_notifier(struct notifier_block *nb) 972 { 973 struct net_device *dev; 974 int err; 975 976 rtnl_lock(); 977 err = raw_notifier_chain_register(&netdev_chain, nb); 978 if (!err) { 979 for (dev = dev_base; dev; dev = dev->next) { 980 nb->notifier_call(nb, NETDEV_REGISTER, dev); 981 982 if (dev->flags & IFF_UP) 983 nb->notifier_call(nb, NETDEV_UP, dev); 984 } 985 } 986 rtnl_unlock(); 987 return err; 988 } 989 990 /** 991 * unregister_netdevice_notifier - unregister a network notifier block 992 * @nb: notifier 993 * 994 * Unregister a notifier previously registered by 995 * register_netdevice_notifier(). The notifier is unlinked into the 996 * kernel structures and may then be reused. A negative errno code 997 * is returned on a failure. 998 */ 999 1000 int unregister_netdevice_notifier(struct notifier_block *nb) 1001 { 1002 int err; 1003 1004 rtnl_lock(); 1005 err = raw_notifier_chain_unregister(&netdev_chain, nb); 1006 rtnl_unlock(); 1007 return err; 1008 } 1009 1010 /** 1011 * call_netdevice_notifiers - call all network notifier blocks 1012 * @val: value passed unmodified to notifier function 1013 * @v: pointer passed unmodified to notifier function 1014 * 1015 * Call all network notifier blocks. Parameters and return value 1016 * are as for raw_notifier_call_chain(). 1017 */ 1018 1019 int call_netdevice_notifiers(unsigned long val, void *v) 1020 { 1021 return raw_notifier_call_chain(&netdev_chain, val, v); 1022 } 1023 1024 /* When > 0 there are consumers of rx skb time stamps */ 1025 static atomic_t netstamp_needed = ATOMIC_INIT(0); 1026 1027 void net_enable_timestamp(void) 1028 { 1029 atomic_inc(&netstamp_needed); 1030 } 1031 1032 void net_disable_timestamp(void) 1033 { 1034 atomic_dec(&netstamp_needed); 1035 } 1036 1037 void __net_timestamp(struct sk_buff *skb) 1038 { 1039 struct timeval tv; 1040 1041 do_gettimeofday(&tv); 1042 skb_set_timestamp(skb, &tv); 1043 } 1044 EXPORT_SYMBOL(__net_timestamp); 1045 1046 static inline void net_timestamp(struct sk_buff *skb) 1047 { 1048 if (atomic_read(&netstamp_needed)) 1049 __net_timestamp(skb); 1050 else { 1051 skb->tstamp.off_sec = 0; 1052 skb->tstamp.off_usec = 0; 1053 } 1054 } 1055 1056 /* 1057 * Support routine. Sends outgoing frames to any network 1058 * taps currently in use. 1059 */ 1060 1061 static void dev_queue_xmit_nit(struct sk_buff *skb, struct net_device *dev) 1062 { 1063 struct packet_type *ptype; 1064 1065 net_timestamp(skb); 1066 1067 rcu_read_lock(); 1068 list_for_each_entry_rcu(ptype, &ptype_all, list) { 1069 /* Never send packets back to the socket 1070 * they originated from - MvS (miquels@drinkel.ow.org) 1071 */ 1072 if ((ptype->dev == dev || !ptype->dev) && 1073 (ptype->af_packet_priv == NULL || 1074 (struct sock *)ptype->af_packet_priv != skb->sk)) { 1075 struct sk_buff *skb2= skb_clone(skb, GFP_ATOMIC); 1076 if (!skb2) 1077 break; 1078 1079 /* skb->nh should be correctly 1080 set by sender, so that the second statement is 1081 just protection against buggy protocols. 1082 */ 1083 skb2->mac.raw = skb2->data; 1084 1085 if (skb2->nh.raw < skb2->data || 1086 skb2->nh.raw > skb2->tail) { 1087 if (net_ratelimit()) 1088 printk(KERN_CRIT "protocol %04x is " 1089 "buggy, dev %s\n", 1090 skb2->protocol, dev->name); 1091 skb2->nh.raw = skb2->data; 1092 } 1093 1094 skb2->h.raw = skb2->nh.raw; 1095 skb2->pkt_type = PACKET_OUTGOING; 1096 ptype->func(skb2, skb->dev, ptype, skb->dev); 1097 } 1098 } 1099 rcu_read_unlock(); 1100 } 1101 1102 1103 void __netif_schedule(struct net_device *dev) 1104 { 1105 if (!test_and_set_bit(__LINK_STATE_SCHED, &dev->state)) { 1106 unsigned long flags; 1107 struct softnet_data *sd; 1108 1109 local_irq_save(flags); 1110 sd = &__get_cpu_var(softnet_data); 1111 dev->next_sched = sd->output_queue; 1112 sd->output_queue = dev; 1113 raise_softirq_irqoff(NET_TX_SOFTIRQ); 1114 local_irq_restore(flags); 1115 } 1116 } 1117 EXPORT_SYMBOL(__netif_schedule); 1118 1119 void __netif_rx_schedule(struct net_device *dev) 1120 { 1121 unsigned long flags; 1122 1123 local_irq_save(flags); 1124 dev_hold(dev); 1125 list_add_tail(&dev->poll_list, &__get_cpu_var(softnet_data).poll_list); 1126 if (dev->quota < 0) 1127 dev->quota += dev->weight; 1128 else 1129 dev->quota = dev->weight; 1130 __raise_softirq_irqoff(NET_RX_SOFTIRQ); 1131 local_irq_restore(flags); 1132 } 1133 EXPORT_SYMBOL(__netif_rx_schedule); 1134 1135 void dev_kfree_skb_any(struct sk_buff *skb) 1136 { 1137 if (in_irq() || irqs_disabled()) 1138 dev_kfree_skb_irq(skb); 1139 else 1140 dev_kfree_skb(skb); 1141 } 1142 EXPORT_SYMBOL(dev_kfree_skb_any); 1143 1144 1145 /* Hot-plugging. */ 1146 void netif_device_detach(struct net_device *dev) 1147 { 1148 if (test_and_clear_bit(__LINK_STATE_PRESENT, &dev->state) && 1149 netif_running(dev)) { 1150 netif_stop_queue(dev); 1151 } 1152 } 1153 EXPORT_SYMBOL(netif_device_detach); 1154 1155 void netif_device_attach(struct net_device *dev) 1156 { 1157 if (!test_and_set_bit(__LINK_STATE_PRESENT, &dev->state) && 1158 netif_running(dev)) { 1159 netif_wake_queue(dev); 1160 __netdev_watchdog_up(dev); 1161 } 1162 } 1163 EXPORT_SYMBOL(netif_device_attach); 1164 1165 1166 /* 1167 * Invalidate hardware checksum when packet is to be mangled, and 1168 * complete checksum manually on outgoing path. 1169 */ 1170 int skb_checksum_help(struct sk_buff *skb) 1171 { 1172 __wsum csum; 1173 int ret = 0, offset = skb->h.raw - skb->data; 1174 1175 if (skb->ip_summed == CHECKSUM_COMPLETE) 1176 goto out_set_summed; 1177 1178 if (unlikely(skb_shinfo(skb)->gso_size)) { 1179 /* Let GSO fix up the checksum. */ 1180 goto out_set_summed; 1181 } 1182 1183 if (skb_cloned(skb)) { 1184 ret = pskb_expand_head(skb, 0, 0, GFP_ATOMIC); 1185 if (ret) 1186 goto out; 1187 } 1188 1189 BUG_ON(offset > (int)skb->len); 1190 csum = skb_checksum(skb, offset, skb->len-offset, 0); 1191 1192 offset = skb->tail - skb->h.raw; 1193 BUG_ON(offset <= 0); 1194 BUG_ON(skb->csum_offset + 2 > offset); 1195 1196 *(__sum16*)(skb->h.raw + skb->csum_offset) = csum_fold(csum); 1197 1198 out_set_summed: 1199 skb->ip_summed = CHECKSUM_NONE; 1200 out: 1201 return ret; 1202 } 1203 1204 /** 1205 * skb_gso_segment - Perform segmentation on skb. 1206 * @skb: buffer to segment 1207 * @features: features for the output path (see dev->features) 1208 * 1209 * This function segments the given skb and returns a list of segments. 1210 * 1211 * It may return NULL if the skb requires no segmentation. This is 1212 * only possible when GSO is used for verifying header integrity. 1213 */ 1214 struct sk_buff *skb_gso_segment(struct sk_buff *skb, int features) 1215 { 1216 struct sk_buff *segs = ERR_PTR(-EPROTONOSUPPORT); 1217 struct packet_type *ptype; 1218 __be16 type = skb->protocol; 1219 int err; 1220 1221 BUG_ON(skb_shinfo(skb)->frag_list); 1222 1223 skb->mac.raw = skb->data; 1224 skb->mac_len = skb->nh.raw - skb->data; 1225 __skb_pull(skb, skb->mac_len); 1226 1227 if (unlikely(skb->ip_summed != CHECKSUM_PARTIAL)) { 1228 if (skb_header_cloned(skb) && 1229 (err = pskb_expand_head(skb, 0, 0, GFP_ATOMIC))) 1230 return ERR_PTR(err); 1231 } 1232 1233 rcu_read_lock(); 1234 list_for_each_entry_rcu(ptype, &ptype_base[ntohs(type) & 15], list) { 1235 if (ptype->type == type && !ptype->dev && ptype->gso_segment) { 1236 if (unlikely(skb->ip_summed != CHECKSUM_PARTIAL)) { 1237 err = ptype->gso_send_check(skb); 1238 segs = ERR_PTR(err); 1239 if (err || skb_gso_ok(skb, features)) 1240 break; 1241 __skb_push(skb, skb->data - skb->nh.raw); 1242 } 1243 segs = ptype->gso_segment(skb, features); 1244 break; 1245 } 1246 } 1247 rcu_read_unlock(); 1248 1249 __skb_push(skb, skb->data - skb->mac.raw); 1250 1251 return segs; 1252 } 1253 1254 EXPORT_SYMBOL(skb_gso_segment); 1255 1256 /* Take action when hardware reception checksum errors are detected. */ 1257 #ifdef CONFIG_BUG 1258 void netdev_rx_csum_fault(struct net_device *dev) 1259 { 1260 if (net_ratelimit()) { 1261 printk(KERN_ERR "%s: hw csum failure.\n", 1262 dev ? dev->name : "<unknown>"); 1263 dump_stack(); 1264 } 1265 } 1266 EXPORT_SYMBOL(netdev_rx_csum_fault); 1267 #endif 1268 1269 /* Actually, we should eliminate this check as soon as we know, that: 1270 * 1. IOMMU is present and allows to map all the memory. 1271 * 2. No high memory really exists on this machine. 1272 */ 1273 1274 static inline int illegal_highdma(struct net_device *dev, struct sk_buff *skb) 1275 { 1276 #ifdef CONFIG_HIGHMEM 1277 int i; 1278 1279 if (dev->features & NETIF_F_HIGHDMA) 1280 return 0; 1281 1282 for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) 1283 if (PageHighMem(skb_shinfo(skb)->frags[i].page)) 1284 return 1; 1285 1286 #endif 1287 return 0; 1288 } 1289 1290 struct dev_gso_cb { 1291 void (*destructor)(struct sk_buff *skb); 1292 }; 1293 1294 #define DEV_GSO_CB(skb) ((struct dev_gso_cb *)(skb)->cb) 1295 1296 static void dev_gso_skb_destructor(struct sk_buff *skb) 1297 { 1298 struct dev_gso_cb *cb; 1299 1300 do { 1301 struct sk_buff *nskb = skb->next; 1302 1303 skb->next = nskb->next; 1304 nskb->next = NULL; 1305 kfree_skb(nskb); 1306 } while (skb->next); 1307 1308 cb = DEV_GSO_CB(skb); 1309 if (cb->destructor) 1310 cb->destructor(skb); 1311 } 1312 1313 /** 1314 * dev_gso_segment - Perform emulated hardware segmentation on skb. 1315 * @skb: buffer to segment 1316 * 1317 * This function segments the given skb and stores the list of segments 1318 * in skb->next. 1319 */ 1320 static int dev_gso_segment(struct sk_buff *skb) 1321 { 1322 struct net_device *dev = skb->dev; 1323 struct sk_buff *segs; 1324 int features = dev->features & ~(illegal_highdma(dev, skb) ? 1325 NETIF_F_SG : 0); 1326 1327 segs = skb_gso_segment(skb, features); 1328 1329 /* Verifying header integrity only. */ 1330 if (!segs) 1331 return 0; 1332 1333 if (unlikely(IS_ERR(segs))) 1334 return PTR_ERR(segs); 1335 1336 skb->next = segs; 1337 DEV_GSO_CB(skb)->destructor = skb->destructor; 1338 skb->destructor = dev_gso_skb_destructor; 1339 1340 return 0; 1341 } 1342 1343 int dev_hard_start_xmit(struct sk_buff *skb, struct net_device *dev) 1344 { 1345 if (likely(!skb->next)) { 1346 if (netdev_nit) 1347 dev_queue_xmit_nit(skb, dev); 1348 1349 if (netif_needs_gso(dev, skb)) { 1350 if (unlikely(dev_gso_segment(skb))) 1351 goto out_kfree_skb; 1352 if (skb->next) 1353 goto gso; 1354 } 1355 1356 return dev->hard_start_xmit(skb, dev); 1357 } 1358 1359 gso: 1360 do { 1361 struct sk_buff *nskb = skb->next; 1362 int rc; 1363 1364 skb->next = nskb->next; 1365 nskb->next = NULL; 1366 rc = dev->hard_start_xmit(nskb, dev); 1367 if (unlikely(rc)) { 1368 nskb->next = skb->next; 1369 skb->next = nskb; 1370 return rc; 1371 } 1372 if (unlikely(netif_queue_stopped(dev) && skb->next)) 1373 return NETDEV_TX_BUSY; 1374 } while (skb->next); 1375 1376 skb->destructor = DEV_GSO_CB(skb)->destructor; 1377 1378 out_kfree_skb: 1379 kfree_skb(skb); 1380 return 0; 1381 } 1382 1383 #define HARD_TX_LOCK(dev, cpu) { \ 1384 if ((dev->features & NETIF_F_LLTX) == 0) { \ 1385 netif_tx_lock(dev); \ 1386 } \ 1387 } 1388 1389 #define HARD_TX_UNLOCK(dev) { \ 1390 if ((dev->features & NETIF_F_LLTX) == 0) { \ 1391 netif_tx_unlock(dev); \ 1392 } \ 1393 } 1394 1395 /** 1396 * dev_queue_xmit - transmit a buffer 1397 * @skb: buffer to transmit 1398 * 1399 * Queue a buffer for transmission to a network device. The caller must 1400 * have set the device and priority and built the buffer before calling 1401 * this function. The function can be called from an interrupt. 1402 * 1403 * A negative errno code is returned on a failure. A success does not 1404 * guarantee the frame will be transmitted as it may be dropped due 1405 * to congestion or traffic shaping. 1406 * 1407 * ----------------------------------------------------------------------------------- 1408 * I notice this method can also return errors from the queue disciplines, 1409 * including NET_XMIT_DROP, which is a positive value. So, errors can also 1410 * be positive. 1411 * 1412 * Regardless of the return value, the skb is consumed, so it is currently 1413 * difficult to retry a send to this method. (You can bump the ref count 1414 * before sending to hold a reference for retry if you are careful.) 1415 * 1416 * When calling this method, interrupts MUST be enabled. This is because 1417 * the BH enable code must have IRQs enabled so that it will not deadlock. 1418 * --BLG 1419 */ 1420 1421 int dev_queue_xmit(struct sk_buff *skb) 1422 { 1423 struct net_device *dev = skb->dev; 1424 struct Qdisc *q; 1425 int rc = -ENOMEM; 1426 1427 /* GSO will handle the following emulations directly. */ 1428 if (netif_needs_gso(dev, skb)) 1429 goto gso; 1430 1431 if (skb_shinfo(skb)->frag_list && 1432 !(dev->features & NETIF_F_FRAGLIST) && 1433 __skb_linearize(skb)) 1434 goto out_kfree_skb; 1435 1436 /* Fragmented skb is linearized if device does not support SG, 1437 * or if at least one of fragments is in highmem and device 1438 * does not support DMA from it. 1439 */ 1440 if (skb_shinfo(skb)->nr_frags && 1441 (!(dev->features & NETIF_F_SG) || illegal_highdma(dev, skb)) && 1442 __skb_linearize(skb)) 1443 goto out_kfree_skb; 1444 1445 /* If packet is not checksummed and device does not support 1446 * checksumming for this protocol, complete checksumming here. 1447 */ 1448 if (skb->ip_summed == CHECKSUM_PARTIAL && 1449 (!(dev->features & NETIF_F_GEN_CSUM) && 1450 (!(dev->features & NETIF_F_IP_CSUM) || 1451 skb->protocol != htons(ETH_P_IP)))) 1452 if (skb_checksum_help(skb)) 1453 goto out_kfree_skb; 1454 1455 gso: 1456 spin_lock_prefetch(&dev->queue_lock); 1457 1458 /* Disable soft irqs for various locks below. Also 1459 * stops preemption for RCU. 1460 */ 1461 rcu_read_lock_bh(); 1462 1463 /* Updates of qdisc are serialized by queue_lock. 1464 * The struct Qdisc which is pointed to by qdisc is now a 1465 * rcu structure - it may be accessed without acquiring 1466 * a lock (but the structure may be stale.) The freeing of the 1467 * qdisc will be deferred until it's known that there are no 1468 * more references to it. 1469 * 1470 * If the qdisc has an enqueue function, we still need to 1471 * hold the queue_lock before calling it, since queue_lock 1472 * also serializes access to the device queue. 1473 */ 1474 1475 q = rcu_dereference(dev->qdisc); 1476 #ifdef CONFIG_NET_CLS_ACT 1477 skb->tc_verd = SET_TC_AT(skb->tc_verd,AT_EGRESS); 1478 #endif 1479 if (q->enqueue) { 1480 /* Grab device queue */ 1481 spin_lock(&dev->queue_lock); 1482 q = dev->qdisc; 1483 if (q->enqueue) { 1484 rc = q->enqueue(skb, q); 1485 qdisc_run(dev); 1486 spin_unlock(&dev->queue_lock); 1487 1488 rc = rc == NET_XMIT_BYPASS ? NET_XMIT_SUCCESS : rc; 1489 goto out; 1490 } 1491 spin_unlock(&dev->queue_lock); 1492 } 1493 1494 /* The device has no queue. Common case for software devices: 1495 loopback, all the sorts of tunnels... 1496 1497 Really, it is unlikely that netif_tx_lock protection is necessary 1498 here. (f.e. loopback and IP tunnels are clean ignoring statistics 1499 counters.) 1500 However, it is possible, that they rely on protection 1501 made by us here. 1502 1503 Check this and shot the lock. It is not prone from deadlocks. 1504 Either shot noqueue qdisc, it is even simpler 8) 1505 */ 1506 if (dev->flags & IFF_UP) { 1507 int cpu = smp_processor_id(); /* ok because BHs are off */ 1508 1509 if (dev->xmit_lock_owner != cpu) { 1510 1511 HARD_TX_LOCK(dev, cpu); 1512 1513 if (!netif_queue_stopped(dev)) { 1514 rc = 0; 1515 if (!dev_hard_start_xmit(skb, dev)) { 1516 HARD_TX_UNLOCK(dev); 1517 goto out; 1518 } 1519 } 1520 HARD_TX_UNLOCK(dev); 1521 if (net_ratelimit()) 1522 printk(KERN_CRIT "Virtual device %s asks to " 1523 "queue packet!\n", dev->name); 1524 } else { 1525 /* Recursion is detected! It is possible, 1526 * unfortunately */ 1527 if (net_ratelimit()) 1528 printk(KERN_CRIT "Dead loop on virtual device " 1529 "%s, fix it urgently!\n", dev->name); 1530 } 1531 } 1532 1533 rc = -ENETDOWN; 1534 rcu_read_unlock_bh(); 1535 1536 out_kfree_skb: 1537 kfree_skb(skb); 1538 return rc; 1539 out: 1540 rcu_read_unlock_bh(); 1541 return rc; 1542 } 1543 1544 1545 /*======================================================================= 1546 Receiver routines 1547 =======================================================================*/ 1548 1549 int netdev_max_backlog = 1000; 1550 int netdev_budget = 300; 1551 int weight_p = 64; /* old backlog weight */ 1552 1553 DEFINE_PER_CPU(struct netif_rx_stats, netdev_rx_stat) = { 0, }; 1554 1555 1556 /** 1557 * netif_rx - post buffer to the network code 1558 * @skb: buffer to post 1559 * 1560 * This function receives a packet from a device driver and queues it for 1561 * the upper (protocol) levels to process. It always succeeds. The buffer 1562 * may be dropped during processing for congestion control or by the 1563 * protocol layers. 1564 * 1565 * return values: 1566 * NET_RX_SUCCESS (no congestion) 1567 * NET_RX_CN_LOW (low congestion) 1568 * NET_RX_CN_MOD (moderate congestion) 1569 * NET_RX_CN_HIGH (high congestion) 1570 * NET_RX_DROP (packet was dropped) 1571 * 1572 */ 1573 1574 int netif_rx(struct sk_buff *skb) 1575 { 1576 struct softnet_data *queue; 1577 unsigned long flags; 1578 1579 /* if netpoll wants it, pretend we never saw it */ 1580 if (netpoll_rx(skb)) 1581 return NET_RX_DROP; 1582 1583 if (!skb->tstamp.off_sec) 1584 net_timestamp(skb); 1585 1586 /* 1587 * The code is rearranged so that the path is the most 1588 * short when CPU is congested, but is still operating. 1589 */ 1590 local_irq_save(flags); 1591 queue = &__get_cpu_var(softnet_data); 1592 1593 __get_cpu_var(netdev_rx_stat).total++; 1594 if (queue->input_pkt_queue.qlen <= netdev_max_backlog) { 1595 if (queue->input_pkt_queue.qlen) { 1596 enqueue: 1597 dev_hold(skb->dev); 1598 __skb_queue_tail(&queue->input_pkt_queue, skb); 1599 local_irq_restore(flags); 1600 return NET_RX_SUCCESS; 1601 } 1602 1603 netif_rx_schedule(&queue->backlog_dev); 1604 goto enqueue; 1605 } 1606 1607 __get_cpu_var(netdev_rx_stat).dropped++; 1608 local_irq_restore(flags); 1609 1610 kfree_skb(skb); 1611 return NET_RX_DROP; 1612 } 1613 1614 int netif_rx_ni(struct sk_buff *skb) 1615 { 1616 int err; 1617 1618 preempt_disable(); 1619 err = netif_rx(skb); 1620 if (local_softirq_pending()) 1621 do_softirq(); 1622 preempt_enable(); 1623 1624 return err; 1625 } 1626 1627 EXPORT_SYMBOL(netif_rx_ni); 1628 1629 static inline struct net_device *skb_bond(struct sk_buff *skb) 1630 { 1631 struct net_device *dev = skb->dev; 1632 1633 if (dev->master) { 1634 if (skb_bond_should_drop(skb)) { 1635 kfree_skb(skb); 1636 return NULL; 1637 } 1638 skb->dev = dev->master; 1639 } 1640 1641 return dev; 1642 } 1643 1644 static void net_tx_action(struct softirq_action *h) 1645 { 1646 struct softnet_data *sd = &__get_cpu_var(softnet_data); 1647 1648 if (sd->completion_queue) { 1649 struct sk_buff *clist; 1650 1651 local_irq_disable(); 1652 clist = sd->completion_queue; 1653 sd->completion_queue = NULL; 1654 local_irq_enable(); 1655 1656 while (clist) { 1657 struct sk_buff *skb = clist; 1658 clist = clist->next; 1659 1660 BUG_TRAP(!atomic_read(&skb->users)); 1661 __kfree_skb(skb); 1662 } 1663 } 1664 1665 if (sd->output_queue) { 1666 struct net_device *head; 1667 1668 local_irq_disable(); 1669 head = sd->output_queue; 1670 sd->output_queue = NULL; 1671 local_irq_enable(); 1672 1673 while (head) { 1674 struct net_device *dev = head; 1675 head = head->next_sched; 1676 1677 smp_mb__before_clear_bit(); 1678 clear_bit(__LINK_STATE_SCHED, &dev->state); 1679 1680 if (spin_trylock(&dev->queue_lock)) { 1681 qdisc_run(dev); 1682 spin_unlock(&dev->queue_lock); 1683 } else { 1684 netif_schedule(dev); 1685 } 1686 } 1687 } 1688 } 1689 1690 static __inline__ int deliver_skb(struct sk_buff *skb, 1691 struct packet_type *pt_prev, 1692 struct net_device *orig_dev) 1693 { 1694 atomic_inc(&skb->users); 1695 return pt_prev->func(skb, skb->dev, pt_prev, orig_dev); 1696 } 1697 1698 #if defined(CONFIG_BRIDGE) || defined (CONFIG_BRIDGE_MODULE) 1699 int (*br_handle_frame_hook)(struct net_bridge_port *p, struct sk_buff **pskb); 1700 struct net_bridge; 1701 struct net_bridge_fdb_entry *(*br_fdb_get_hook)(struct net_bridge *br, 1702 unsigned char *addr); 1703 void (*br_fdb_put_hook)(struct net_bridge_fdb_entry *ent); 1704 1705 static __inline__ int handle_bridge(struct sk_buff **pskb, 1706 struct packet_type **pt_prev, int *ret, 1707 struct net_device *orig_dev) 1708 { 1709 struct net_bridge_port *port; 1710 1711 if ((*pskb)->pkt_type == PACKET_LOOPBACK || 1712 (port = rcu_dereference((*pskb)->dev->br_port)) == NULL) 1713 return 0; 1714 1715 if (*pt_prev) { 1716 *ret = deliver_skb(*pskb, *pt_prev, orig_dev); 1717 *pt_prev = NULL; 1718 } 1719 1720 return br_handle_frame_hook(port, pskb); 1721 } 1722 #else 1723 #define handle_bridge(skb, pt_prev, ret, orig_dev) (0) 1724 #endif 1725 1726 #ifdef CONFIG_NET_CLS_ACT 1727 /* TODO: Maybe we should just force sch_ingress to be compiled in 1728 * when CONFIG_NET_CLS_ACT is? otherwise some useless instructions 1729 * a compare and 2 stores extra right now if we dont have it on 1730 * but have CONFIG_NET_CLS_ACT 1731 * NOTE: This doesnt stop any functionality; if you dont have 1732 * the ingress scheduler, you just cant add policies on ingress. 1733 * 1734 */ 1735 static int ing_filter(struct sk_buff *skb) 1736 { 1737 struct Qdisc *q; 1738 struct net_device *dev = skb->dev; 1739 int result = TC_ACT_OK; 1740 1741 if (dev->qdisc_ingress) { 1742 __u32 ttl = (__u32) G_TC_RTTL(skb->tc_verd); 1743 if (MAX_RED_LOOP < ttl++) { 1744 printk(KERN_WARNING "Redir loop detected Dropping packet (%s->%s)\n", 1745 skb->input_dev->name, skb->dev->name); 1746 return TC_ACT_SHOT; 1747 } 1748 1749 skb->tc_verd = SET_TC_RTTL(skb->tc_verd,ttl); 1750 1751 skb->tc_verd = SET_TC_AT(skb->tc_verd,AT_INGRESS); 1752 1753 spin_lock(&dev->ingress_lock); 1754 if ((q = dev->qdisc_ingress) != NULL) 1755 result = q->enqueue(skb, q); 1756 spin_unlock(&dev->ingress_lock); 1757 1758 } 1759 1760 return result; 1761 } 1762 #endif 1763 1764 int netif_receive_skb(struct sk_buff *skb) 1765 { 1766 struct packet_type *ptype, *pt_prev; 1767 struct net_device *orig_dev; 1768 int ret = NET_RX_DROP; 1769 __be16 type; 1770 1771 /* if we've gotten here through NAPI, check netpoll */ 1772 if (skb->dev->poll && netpoll_rx(skb)) 1773 return NET_RX_DROP; 1774 1775 if (!skb->tstamp.off_sec) 1776 net_timestamp(skb); 1777 1778 if (!skb->input_dev) 1779 skb->input_dev = skb->dev; 1780 1781 orig_dev = skb_bond(skb); 1782 1783 if (!orig_dev) 1784 return NET_RX_DROP; 1785 1786 __get_cpu_var(netdev_rx_stat).total++; 1787 1788 skb->h.raw = skb->nh.raw = skb->data; 1789 skb->mac_len = skb->nh.raw - skb->mac.raw; 1790 1791 pt_prev = NULL; 1792 1793 rcu_read_lock(); 1794 1795 #ifdef CONFIG_NET_CLS_ACT 1796 if (skb->tc_verd & TC_NCLS) { 1797 skb->tc_verd = CLR_TC_NCLS(skb->tc_verd); 1798 goto ncls; 1799 } 1800 #endif 1801 1802 list_for_each_entry_rcu(ptype, &ptype_all, list) { 1803 if (!ptype->dev || ptype->dev == skb->dev) { 1804 if (pt_prev) 1805 ret = deliver_skb(skb, pt_prev, orig_dev); 1806 pt_prev = ptype; 1807 } 1808 } 1809 1810 #ifdef CONFIG_NET_CLS_ACT 1811 if (pt_prev) { 1812 ret = deliver_skb(skb, pt_prev, orig_dev); 1813 pt_prev = NULL; /* noone else should process this after*/ 1814 } else { 1815 skb->tc_verd = SET_TC_OK2MUNGE(skb->tc_verd); 1816 } 1817 1818 ret = ing_filter(skb); 1819 1820 if (ret == TC_ACT_SHOT || (ret == TC_ACT_STOLEN)) { 1821 kfree_skb(skb); 1822 goto out; 1823 } 1824 1825 skb->tc_verd = 0; 1826 ncls: 1827 #endif 1828 1829 if (handle_bridge(&skb, &pt_prev, &ret, orig_dev)) 1830 goto out; 1831 1832 type = skb->protocol; 1833 list_for_each_entry_rcu(ptype, &ptype_base[ntohs(type)&15], list) { 1834 if (ptype->type == type && 1835 (!ptype->dev || ptype->dev == skb->dev)) { 1836 if (pt_prev) 1837 ret = deliver_skb(skb, pt_prev, orig_dev); 1838 pt_prev = ptype; 1839 } 1840 } 1841 1842 if (pt_prev) { 1843 ret = pt_prev->func(skb, skb->dev, pt_prev, orig_dev); 1844 } else { 1845 kfree_skb(skb); 1846 /* Jamal, now you will not able to escape explaining 1847 * me how you were going to use this. :-) 1848 */ 1849 ret = NET_RX_DROP; 1850 } 1851 1852 out: 1853 rcu_read_unlock(); 1854 return ret; 1855 } 1856 1857 static int process_backlog(struct net_device *backlog_dev, int *budget) 1858 { 1859 int work = 0; 1860 int quota = min(backlog_dev->quota, *budget); 1861 struct softnet_data *queue = &__get_cpu_var(softnet_data); 1862 unsigned long start_time = jiffies; 1863 1864 backlog_dev->weight = weight_p; 1865 for (;;) { 1866 struct sk_buff *skb; 1867 struct net_device *dev; 1868 1869 local_irq_disable(); 1870 skb = __skb_dequeue(&queue->input_pkt_queue); 1871 if (!skb) 1872 goto job_done; 1873 local_irq_enable(); 1874 1875 dev = skb->dev; 1876 1877 netif_receive_skb(skb); 1878 1879 dev_put(dev); 1880 1881 work++; 1882 1883 if (work >= quota || jiffies - start_time > 1) 1884 break; 1885 1886 } 1887 1888 backlog_dev->quota -= work; 1889 *budget -= work; 1890 return -1; 1891 1892 job_done: 1893 backlog_dev->quota -= work; 1894 *budget -= work; 1895 1896 list_del(&backlog_dev->poll_list); 1897 smp_mb__before_clear_bit(); 1898 netif_poll_enable(backlog_dev); 1899 1900 local_irq_enable(); 1901 return 0; 1902 } 1903 1904 static void net_rx_action(struct softirq_action *h) 1905 { 1906 struct softnet_data *queue = &__get_cpu_var(softnet_data); 1907 unsigned long start_time = jiffies; 1908 int budget = netdev_budget; 1909 void *have; 1910 1911 local_irq_disable(); 1912 1913 while (!list_empty(&queue->poll_list)) { 1914 struct net_device *dev; 1915 1916 if (budget <= 0 || jiffies - start_time > 1) 1917 goto softnet_break; 1918 1919 local_irq_enable(); 1920 1921 dev = list_entry(queue->poll_list.next, 1922 struct net_device, poll_list); 1923 have = netpoll_poll_lock(dev); 1924 1925 if (dev->quota <= 0 || dev->poll(dev, &budget)) { 1926 netpoll_poll_unlock(have); 1927 local_irq_disable(); 1928 list_move_tail(&dev->poll_list, &queue->poll_list); 1929 if (dev->quota < 0) 1930 dev->quota += dev->weight; 1931 else 1932 dev->quota = dev->weight; 1933 } else { 1934 netpoll_poll_unlock(have); 1935 dev_put(dev); 1936 local_irq_disable(); 1937 } 1938 } 1939 out: 1940 #ifdef CONFIG_NET_DMA 1941 /* 1942 * There may not be any more sk_buffs coming right now, so push 1943 * any pending DMA copies to hardware 1944 */ 1945 if (net_dma_client) { 1946 struct dma_chan *chan; 1947 rcu_read_lock(); 1948 list_for_each_entry_rcu(chan, &net_dma_client->channels, client_node) 1949 dma_async_memcpy_issue_pending(chan); 1950 rcu_read_unlock(); 1951 } 1952 #endif 1953 local_irq_enable(); 1954 return; 1955 1956 softnet_break: 1957 __get_cpu_var(netdev_rx_stat).time_squeeze++; 1958 __raise_softirq_irqoff(NET_RX_SOFTIRQ); 1959 goto out; 1960 } 1961 1962 static gifconf_func_t * gifconf_list [NPROTO]; 1963 1964 /** 1965 * register_gifconf - register a SIOCGIF handler 1966 * @family: Address family 1967 * @gifconf: Function handler 1968 * 1969 * Register protocol dependent address dumping routines. The handler 1970 * that is passed must not be freed or reused until it has been replaced 1971 * by another handler. 1972 */ 1973 int register_gifconf(unsigned int family, gifconf_func_t * gifconf) 1974 { 1975 if (family >= NPROTO) 1976 return -EINVAL; 1977 gifconf_list[family] = gifconf; 1978 return 0; 1979 } 1980 1981 1982 /* 1983 * Map an interface index to its name (SIOCGIFNAME) 1984 */ 1985 1986 /* 1987 * We need this ioctl for efficient implementation of the 1988 * if_indextoname() function required by the IPv6 API. Without 1989 * it, we would have to search all the interfaces to find a 1990 * match. --pb 1991 */ 1992 1993 static int dev_ifname(struct ifreq __user *arg) 1994 { 1995 struct net_device *dev; 1996 struct ifreq ifr; 1997 1998 /* 1999 * Fetch the caller's info block. 2000 */ 2001 2002 if (copy_from_user(&ifr, arg, sizeof(struct ifreq))) 2003 return -EFAULT; 2004 2005 read_lock(&dev_base_lock); 2006 dev = __dev_get_by_index(ifr.ifr_ifindex); 2007 if (!dev) { 2008 read_unlock(&dev_base_lock); 2009 return -ENODEV; 2010 } 2011 2012 strcpy(ifr.ifr_name, dev->name); 2013 read_unlock(&dev_base_lock); 2014 2015 if (copy_to_user(arg, &ifr, sizeof(struct ifreq))) 2016 return -EFAULT; 2017 return 0; 2018 } 2019 2020 /* 2021 * Perform a SIOCGIFCONF call. This structure will change 2022 * size eventually, and there is nothing I can do about it. 2023 * Thus we will need a 'compatibility mode'. 2024 */ 2025 2026 static int dev_ifconf(char __user *arg) 2027 { 2028 struct ifconf ifc; 2029 struct net_device *dev; 2030 char __user *pos; 2031 int len; 2032 int total; 2033 int i; 2034 2035 /* 2036 * Fetch the caller's info block. 2037 */ 2038 2039 if (copy_from_user(&ifc, arg, sizeof(struct ifconf))) 2040 return -EFAULT; 2041 2042 pos = ifc.ifc_buf; 2043 len = ifc.ifc_len; 2044 2045 /* 2046 * Loop over the interfaces, and write an info block for each. 2047 */ 2048 2049 total = 0; 2050 for (dev = dev_base; dev; dev = dev->next) { 2051 for (i = 0; i < NPROTO; i++) { 2052 if (gifconf_list[i]) { 2053 int done; 2054 if (!pos) 2055 done = gifconf_list[i](dev, NULL, 0); 2056 else 2057 done = gifconf_list[i](dev, pos + total, 2058 len - total); 2059 if (done < 0) 2060 return -EFAULT; 2061 total += done; 2062 } 2063 } 2064 } 2065 2066 /* 2067 * All done. Write the updated control block back to the caller. 2068 */ 2069 ifc.ifc_len = total; 2070 2071 /* 2072 * Both BSD and Solaris return 0 here, so we do too. 2073 */ 2074 return copy_to_user(arg, &ifc, sizeof(struct ifconf)) ? -EFAULT : 0; 2075 } 2076 2077 #ifdef CONFIG_PROC_FS 2078 /* 2079 * This is invoked by the /proc filesystem handler to display a device 2080 * in detail. 2081 */ 2082 static __inline__ struct net_device *dev_get_idx(loff_t pos) 2083 { 2084 struct net_device *dev; 2085 loff_t i; 2086 2087 for (i = 0, dev = dev_base; dev && i < pos; ++i, dev = dev->next); 2088 2089 return i == pos ? dev : NULL; 2090 } 2091 2092 void *dev_seq_start(struct seq_file *seq, loff_t *pos) 2093 { 2094 read_lock(&dev_base_lock); 2095 return *pos ? dev_get_idx(*pos - 1) : SEQ_START_TOKEN; 2096 } 2097 2098 void *dev_seq_next(struct seq_file *seq, void *v, loff_t *pos) 2099 { 2100 ++*pos; 2101 return v == SEQ_START_TOKEN ? dev_base : ((struct net_device *)v)->next; 2102 } 2103 2104 void dev_seq_stop(struct seq_file *seq, void *v) 2105 { 2106 read_unlock(&dev_base_lock); 2107 } 2108 2109 static void dev_seq_printf_stats(struct seq_file *seq, struct net_device *dev) 2110 { 2111 if (dev->get_stats) { 2112 struct net_device_stats *stats = dev->get_stats(dev); 2113 2114 seq_printf(seq, "%6s:%8lu %7lu %4lu %4lu %4lu %5lu %10lu %9lu " 2115 "%8lu %7lu %4lu %4lu %4lu %5lu %7lu %10lu\n", 2116 dev->name, stats->rx_bytes, stats->rx_packets, 2117 stats->rx_errors, 2118 stats->rx_dropped + stats->rx_missed_errors, 2119 stats->rx_fifo_errors, 2120 stats->rx_length_errors + stats->rx_over_errors + 2121 stats->rx_crc_errors + stats->rx_frame_errors, 2122 stats->rx_compressed, stats->multicast, 2123 stats->tx_bytes, stats->tx_packets, 2124 stats->tx_errors, stats->tx_dropped, 2125 stats->tx_fifo_errors, stats->collisions, 2126 stats->tx_carrier_errors + 2127 stats->tx_aborted_errors + 2128 stats->tx_window_errors + 2129 stats->tx_heartbeat_errors, 2130 stats->tx_compressed); 2131 } else 2132 seq_printf(seq, "%6s: No statistics available.\n", dev->name); 2133 } 2134 2135 /* 2136 * Called from the PROCfs module. This now uses the new arbitrary sized 2137 * /proc/net interface to create /proc/net/dev 2138 */ 2139 static int dev_seq_show(struct seq_file *seq, void *v) 2140 { 2141 if (v == SEQ_START_TOKEN) 2142 seq_puts(seq, "Inter-| Receive " 2143 " | Transmit\n" 2144 " face |bytes packets errs drop fifo frame " 2145 "compressed multicast|bytes packets errs " 2146 "drop fifo colls carrier compressed\n"); 2147 else 2148 dev_seq_printf_stats(seq, v); 2149 return 0; 2150 } 2151 2152 static struct netif_rx_stats *softnet_get_online(loff_t *pos) 2153 { 2154 struct netif_rx_stats *rc = NULL; 2155 2156 while (*pos < NR_CPUS) 2157 if (cpu_online(*pos)) { 2158 rc = &per_cpu(netdev_rx_stat, *pos); 2159 break; 2160 } else 2161 ++*pos; 2162 return rc; 2163 } 2164 2165 static void *softnet_seq_start(struct seq_file *seq, loff_t *pos) 2166 { 2167 return softnet_get_online(pos); 2168 } 2169 2170 static void *softnet_seq_next(struct seq_file *seq, void *v, loff_t *pos) 2171 { 2172 ++*pos; 2173 return softnet_get_online(pos); 2174 } 2175 2176 static void softnet_seq_stop(struct seq_file *seq, void *v) 2177 { 2178 } 2179 2180 static int softnet_seq_show(struct seq_file *seq, void *v) 2181 { 2182 struct netif_rx_stats *s = v; 2183 2184 seq_printf(seq, "%08x %08x %08x %08x %08x %08x %08x %08x %08x\n", 2185 s->total, s->dropped, s->time_squeeze, 0, 2186 0, 0, 0, 0, /* was fastroute */ 2187 s->cpu_collision ); 2188 return 0; 2189 } 2190 2191 static struct seq_operations dev_seq_ops = { 2192 .start = dev_seq_start, 2193 .next = dev_seq_next, 2194 .stop = dev_seq_stop, 2195 .show = dev_seq_show, 2196 }; 2197 2198 static int dev_seq_open(struct inode *inode, struct file *file) 2199 { 2200 return seq_open(file, &dev_seq_ops); 2201 } 2202 2203 static struct file_operations dev_seq_fops = { 2204 .owner = THIS_MODULE, 2205 .open = dev_seq_open, 2206 .read = seq_read, 2207 .llseek = seq_lseek, 2208 .release = seq_release, 2209 }; 2210 2211 static struct seq_operations softnet_seq_ops = { 2212 .start = softnet_seq_start, 2213 .next = softnet_seq_next, 2214 .stop = softnet_seq_stop, 2215 .show = softnet_seq_show, 2216 }; 2217 2218 static int softnet_seq_open(struct inode *inode, struct file *file) 2219 { 2220 return seq_open(file, &softnet_seq_ops); 2221 } 2222 2223 static struct file_operations softnet_seq_fops = { 2224 .owner = THIS_MODULE, 2225 .open = softnet_seq_open, 2226 .read = seq_read, 2227 .llseek = seq_lseek, 2228 .release = seq_release, 2229 }; 2230 2231 #ifdef CONFIG_WIRELESS_EXT 2232 extern int wireless_proc_init(void); 2233 #else 2234 #define wireless_proc_init() 0 2235 #endif 2236 2237 static int __init dev_proc_init(void) 2238 { 2239 int rc = -ENOMEM; 2240 2241 if (!proc_net_fops_create("dev", S_IRUGO, &dev_seq_fops)) 2242 goto out; 2243 if (!proc_net_fops_create("softnet_stat", S_IRUGO, &softnet_seq_fops)) 2244 goto out_dev; 2245 if (wireless_proc_init()) 2246 goto out_softnet; 2247 rc = 0; 2248 out: 2249 return rc; 2250 out_softnet: 2251 proc_net_remove("softnet_stat"); 2252 out_dev: 2253 proc_net_remove("dev"); 2254 goto out; 2255 } 2256 #else 2257 #define dev_proc_init() 0 2258 #endif /* CONFIG_PROC_FS */ 2259 2260 2261 /** 2262 * netdev_set_master - set up master/slave pair 2263 * @slave: slave device 2264 * @master: new master device 2265 * 2266 * Changes the master device of the slave. Pass %NULL to break the 2267 * bonding. The caller must hold the RTNL semaphore. On a failure 2268 * a negative errno code is returned. On success the reference counts 2269 * are adjusted, %RTM_NEWLINK is sent to the routing socket and the 2270 * function returns zero. 2271 */ 2272 int netdev_set_master(struct net_device *slave, struct net_device *master) 2273 { 2274 struct net_device *old = slave->master; 2275 2276 ASSERT_RTNL(); 2277 2278 if (master) { 2279 if (old) 2280 return -EBUSY; 2281 dev_hold(master); 2282 } 2283 2284 slave->master = master; 2285 2286 synchronize_net(); 2287 2288 if (old) 2289 dev_put(old); 2290 2291 if (master) 2292 slave->flags |= IFF_SLAVE; 2293 else 2294 slave->flags &= ~IFF_SLAVE; 2295 2296 rtmsg_ifinfo(RTM_NEWLINK, slave, IFF_SLAVE); 2297 return 0; 2298 } 2299 2300 /** 2301 * dev_set_promiscuity - update promiscuity count on a device 2302 * @dev: device 2303 * @inc: modifier 2304 * 2305 * Add or remove promiscuity from a device. While the count in the device 2306 * remains above zero the interface remains promiscuous. Once it hits zero 2307 * the device reverts back to normal filtering operation. A negative inc 2308 * value is used to drop promiscuity on the device. 2309 */ 2310 void dev_set_promiscuity(struct net_device *dev, int inc) 2311 { 2312 unsigned short old_flags = dev->flags; 2313 2314 if ((dev->promiscuity += inc) == 0) 2315 dev->flags &= ~IFF_PROMISC; 2316 else 2317 dev->flags |= IFF_PROMISC; 2318 if (dev->flags != old_flags) { 2319 dev_mc_upload(dev); 2320 printk(KERN_INFO "device %s %s promiscuous mode\n", 2321 dev->name, (dev->flags & IFF_PROMISC) ? "entered" : 2322 "left"); 2323 audit_log(current->audit_context, GFP_ATOMIC, 2324 AUDIT_ANOM_PROMISCUOUS, 2325 "dev=%s prom=%d old_prom=%d auid=%u", 2326 dev->name, (dev->flags & IFF_PROMISC), 2327 (old_flags & IFF_PROMISC), 2328 audit_get_loginuid(current->audit_context)); 2329 } 2330 } 2331 2332 /** 2333 * dev_set_allmulti - update allmulti count on a device 2334 * @dev: device 2335 * @inc: modifier 2336 * 2337 * Add or remove reception of all multicast frames to a device. While the 2338 * count in the device remains above zero the interface remains listening 2339 * to all interfaces. Once it hits zero the device reverts back to normal 2340 * filtering operation. A negative @inc value is used to drop the counter 2341 * when releasing a resource needing all multicasts. 2342 */ 2343 2344 void dev_set_allmulti(struct net_device *dev, int inc) 2345 { 2346 unsigned short old_flags = dev->flags; 2347 2348 dev->flags |= IFF_ALLMULTI; 2349 if ((dev->allmulti += inc) == 0) 2350 dev->flags &= ~IFF_ALLMULTI; 2351 if (dev->flags ^ old_flags) 2352 dev_mc_upload(dev); 2353 } 2354 2355 unsigned dev_get_flags(const struct net_device *dev) 2356 { 2357 unsigned flags; 2358 2359 flags = (dev->flags & ~(IFF_PROMISC | 2360 IFF_ALLMULTI | 2361 IFF_RUNNING | 2362 IFF_LOWER_UP | 2363 IFF_DORMANT)) | 2364 (dev->gflags & (IFF_PROMISC | 2365 IFF_ALLMULTI)); 2366 2367 if (netif_running(dev)) { 2368 if (netif_oper_up(dev)) 2369 flags |= IFF_RUNNING; 2370 if (netif_carrier_ok(dev)) 2371 flags |= IFF_LOWER_UP; 2372 if (netif_dormant(dev)) 2373 flags |= IFF_DORMANT; 2374 } 2375 2376 return flags; 2377 } 2378 2379 int dev_change_flags(struct net_device *dev, unsigned flags) 2380 { 2381 int ret; 2382 int old_flags = dev->flags; 2383 2384 /* 2385 * Set the flags on our device. 2386 */ 2387 2388 dev->flags = (flags & (IFF_DEBUG | IFF_NOTRAILERS | IFF_NOARP | 2389 IFF_DYNAMIC | IFF_MULTICAST | IFF_PORTSEL | 2390 IFF_AUTOMEDIA)) | 2391 (dev->flags & (IFF_UP | IFF_VOLATILE | IFF_PROMISC | 2392 IFF_ALLMULTI)); 2393 2394 /* 2395 * Load in the correct multicast list now the flags have changed. 2396 */ 2397 2398 dev_mc_upload(dev); 2399 2400 /* 2401 * Have we downed the interface. We handle IFF_UP ourselves 2402 * according to user attempts to set it, rather than blindly 2403 * setting it. 2404 */ 2405 2406 ret = 0; 2407 if ((old_flags ^ flags) & IFF_UP) { /* Bit is different ? */ 2408 ret = ((old_flags & IFF_UP) ? dev_close : dev_open)(dev); 2409 2410 if (!ret) 2411 dev_mc_upload(dev); 2412 } 2413 2414 if (dev->flags & IFF_UP && 2415 ((old_flags ^ dev->flags) &~ (IFF_UP | IFF_PROMISC | IFF_ALLMULTI | 2416 IFF_VOLATILE))) 2417 raw_notifier_call_chain(&netdev_chain, 2418 NETDEV_CHANGE, dev); 2419 2420 if ((flags ^ dev->gflags) & IFF_PROMISC) { 2421 int inc = (flags & IFF_PROMISC) ? +1 : -1; 2422 dev->gflags ^= IFF_PROMISC; 2423 dev_set_promiscuity(dev, inc); 2424 } 2425 2426 /* NOTE: order of synchronization of IFF_PROMISC and IFF_ALLMULTI 2427 is important. Some (broken) drivers set IFF_PROMISC, when 2428 IFF_ALLMULTI is requested not asking us and not reporting. 2429 */ 2430 if ((flags ^ dev->gflags) & IFF_ALLMULTI) { 2431 int inc = (flags & IFF_ALLMULTI) ? +1 : -1; 2432 dev->gflags ^= IFF_ALLMULTI; 2433 dev_set_allmulti(dev, inc); 2434 } 2435 2436 if (old_flags ^ dev->flags) 2437 rtmsg_ifinfo(RTM_NEWLINK, dev, old_flags ^ dev->flags); 2438 2439 return ret; 2440 } 2441 2442 int dev_set_mtu(struct net_device *dev, int new_mtu) 2443 { 2444 int err; 2445 2446 if (new_mtu == dev->mtu) 2447 return 0; 2448 2449 /* MTU must be positive. */ 2450 if (new_mtu < 0) 2451 return -EINVAL; 2452 2453 if (!netif_device_present(dev)) 2454 return -ENODEV; 2455 2456 err = 0; 2457 if (dev->change_mtu) 2458 err = dev->change_mtu(dev, new_mtu); 2459 else 2460 dev->mtu = new_mtu; 2461 if (!err && dev->flags & IFF_UP) 2462 raw_notifier_call_chain(&netdev_chain, 2463 NETDEV_CHANGEMTU, dev); 2464 return err; 2465 } 2466 2467 int dev_set_mac_address(struct net_device *dev, struct sockaddr *sa) 2468 { 2469 int err; 2470 2471 if (!dev->set_mac_address) 2472 return -EOPNOTSUPP; 2473 if (sa->sa_family != dev->type) 2474 return -EINVAL; 2475 if (!netif_device_present(dev)) 2476 return -ENODEV; 2477 err = dev->set_mac_address(dev, sa); 2478 if (!err) 2479 raw_notifier_call_chain(&netdev_chain, 2480 NETDEV_CHANGEADDR, dev); 2481 return err; 2482 } 2483 2484 /* 2485 * Perform the SIOCxIFxxx calls. 2486 */ 2487 static int dev_ifsioc(struct ifreq *ifr, unsigned int cmd) 2488 { 2489 int err; 2490 struct net_device *dev = __dev_get_by_name(ifr->ifr_name); 2491 2492 if (!dev) 2493 return -ENODEV; 2494 2495 switch (cmd) { 2496 case SIOCGIFFLAGS: /* Get interface flags */ 2497 ifr->ifr_flags = dev_get_flags(dev); 2498 return 0; 2499 2500 case SIOCSIFFLAGS: /* Set interface flags */ 2501 return dev_change_flags(dev, ifr->ifr_flags); 2502 2503 case SIOCGIFMETRIC: /* Get the metric on the interface 2504 (currently unused) */ 2505 ifr->ifr_metric = 0; 2506 return 0; 2507 2508 case SIOCSIFMETRIC: /* Set the metric on the interface 2509 (currently unused) */ 2510 return -EOPNOTSUPP; 2511 2512 case SIOCGIFMTU: /* Get the MTU of a device */ 2513 ifr->ifr_mtu = dev->mtu; 2514 return 0; 2515 2516 case SIOCSIFMTU: /* Set the MTU of a device */ 2517 return dev_set_mtu(dev, ifr->ifr_mtu); 2518 2519 case SIOCGIFHWADDR: 2520 if (!dev->addr_len) 2521 memset(ifr->ifr_hwaddr.sa_data, 0, sizeof ifr->ifr_hwaddr.sa_data); 2522 else 2523 memcpy(ifr->ifr_hwaddr.sa_data, dev->dev_addr, 2524 min(sizeof ifr->ifr_hwaddr.sa_data, (size_t) dev->addr_len)); 2525 ifr->ifr_hwaddr.sa_family = dev->type; 2526 return 0; 2527 2528 case SIOCSIFHWADDR: 2529 return dev_set_mac_address(dev, &ifr->ifr_hwaddr); 2530 2531 case SIOCSIFHWBROADCAST: 2532 if (ifr->ifr_hwaddr.sa_family != dev->type) 2533 return -EINVAL; 2534 memcpy(dev->broadcast, ifr->ifr_hwaddr.sa_data, 2535 min(sizeof ifr->ifr_hwaddr.sa_data, (size_t) dev->addr_len)); 2536 raw_notifier_call_chain(&netdev_chain, 2537 NETDEV_CHANGEADDR, dev); 2538 return 0; 2539 2540 case SIOCGIFMAP: 2541 ifr->ifr_map.mem_start = dev->mem_start; 2542 ifr->ifr_map.mem_end = dev->mem_end; 2543 ifr->ifr_map.base_addr = dev->base_addr; 2544 ifr->ifr_map.irq = dev->irq; 2545 ifr->ifr_map.dma = dev->dma; 2546 ifr->ifr_map.port = dev->if_port; 2547 return 0; 2548 2549 case SIOCSIFMAP: 2550 if (dev->set_config) { 2551 if (!netif_device_present(dev)) 2552 return -ENODEV; 2553 return dev->set_config(dev, &ifr->ifr_map); 2554 } 2555 return -EOPNOTSUPP; 2556 2557 case SIOCADDMULTI: 2558 if (!dev->set_multicast_list || 2559 ifr->ifr_hwaddr.sa_family != AF_UNSPEC) 2560 return -EINVAL; 2561 if (!netif_device_present(dev)) 2562 return -ENODEV; 2563 return dev_mc_add(dev, ifr->ifr_hwaddr.sa_data, 2564 dev->addr_len, 1); 2565 2566 case SIOCDELMULTI: 2567 if (!dev->set_multicast_list || 2568 ifr->ifr_hwaddr.sa_family != AF_UNSPEC) 2569 return -EINVAL; 2570 if (!netif_device_present(dev)) 2571 return -ENODEV; 2572 return dev_mc_delete(dev, ifr->ifr_hwaddr.sa_data, 2573 dev->addr_len, 1); 2574 2575 case SIOCGIFINDEX: 2576 ifr->ifr_ifindex = dev->ifindex; 2577 return 0; 2578 2579 case SIOCGIFTXQLEN: 2580 ifr->ifr_qlen = dev->tx_queue_len; 2581 return 0; 2582 2583 case SIOCSIFTXQLEN: 2584 if (ifr->ifr_qlen < 0) 2585 return -EINVAL; 2586 dev->tx_queue_len = ifr->ifr_qlen; 2587 return 0; 2588 2589 case SIOCSIFNAME: 2590 ifr->ifr_newname[IFNAMSIZ-1] = '\0'; 2591 return dev_change_name(dev, ifr->ifr_newname); 2592 2593 /* 2594 * Unknown or private ioctl 2595 */ 2596 2597 default: 2598 if ((cmd >= SIOCDEVPRIVATE && 2599 cmd <= SIOCDEVPRIVATE + 15) || 2600 cmd == SIOCBONDENSLAVE || 2601 cmd == SIOCBONDRELEASE || 2602 cmd == SIOCBONDSETHWADDR || 2603 cmd == SIOCBONDSLAVEINFOQUERY || 2604 cmd == SIOCBONDINFOQUERY || 2605 cmd == SIOCBONDCHANGEACTIVE || 2606 cmd == SIOCGMIIPHY || 2607 cmd == SIOCGMIIREG || 2608 cmd == SIOCSMIIREG || 2609 cmd == SIOCBRADDIF || 2610 cmd == SIOCBRDELIF || 2611 cmd == SIOCWANDEV) { 2612 err = -EOPNOTSUPP; 2613 if (dev->do_ioctl) { 2614 if (netif_device_present(dev)) 2615 err = dev->do_ioctl(dev, ifr, 2616 cmd); 2617 else 2618 err = -ENODEV; 2619 } 2620 } else 2621 err = -EINVAL; 2622 2623 } 2624 return err; 2625 } 2626 2627 /* 2628 * This function handles all "interface"-type I/O control requests. The actual 2629 * 'doing' part of this is dev_ifsioc above. 2630 */ 2631 2632 /** 2633 * dev_ioctl - network device ioctl 2634 * @cmd: command to issue 2635 * @arg: pointer to a struct ifreq in user space 2636 * 2637 * Issue ioctl functions to devices. This is normally called by the 2638 * user space syscall interfaces but can sometimes be useful for 2639 * other purposes. The return value is the return from the syscall if 2640 * positive or a negative errno code on error. 2641 */ 2642 2643 int dev_ioctl(unsigned int cmd, void __user *arg) 2644 { 2645 struct ifreq ifr; 2646 int ret; 2647 char *colon; 2648 2649 /* One special case: SIOCGIFCONF takes ifconf argument 2650 and requires shared lock, because it sleeps writing 2651 to user space. 2652 */ 2653 2654 if (cmd == SIOCGIFCONF) { 2655 rtnl_lock(); 2656 ret = dev_ifconf((char __user *) arg); 2657 rtnl_unlock(); 2658 return ret; 2659 } 2660 if (cmd == SIOCGIFNAME) 2661 return dev_ifname((struct ifreq __user *)arg); 2662 2663 if (copy_from_user(&ifr, arg, sizeof(struct ifreq))) 2664 return -EFAULT; 2665 2666 ifr.ifr_name[IFNAMSIZ-1] = 0; 2667 2668 colon = strchr(ifr.ifr_name, ':'); 2669 if (colon) 2670 *colon = 0; 2671 2672 /* 2673 * See which interface the caller is talking about. 2674 */ 2675 2676 switch (cmd) { 2677 /* 2678 * These ioctl calls: 2679 * - can be done by all. 2680 * - atomic and do not require locking. 2681 * - return a value 2682 */ 2683 case SIOCGIFFLAGS: 2684 case SIOCGIFMETRIC: 2685 case SIOCGIFMTU: 2686 case SIOCGIFHWADDR: 2687 case SIOCGIFSLAVE: 2688 case SIOCGIFMAP: 2689 case SIOCGIFINDEX: 2690 case SIOCGIFTXQLEN: 2691 dev_load(ifr.ifr_name); 2692 read_lock(&dev_base_lock); 2693 ret = dev_ifsioc(&ifr, cmd); 2694 read_unlock(&dev_base_lock); 2695 if (!ret) { 2696 if (colon) 2697 *colon = ':'; 2698 if (copy_to_user(arg, &ifr, 2699 sizeof(struct ifreq))) 2700 ret = -EFAULT; 2701 } 2702 return ret; 2703 2704 case SIOCETHTOOL: 2705 dev_load(ifr.ifr_name); 2706 rtnl_lock(); 2707 ret = dev_ethtool(&ifr); 2708 rtnl_unlock(); 2709 if (!ret) { 2710 if (colon) 2711 *colon = ':'; 2712 if (copy_to_user(arg, &ifr, 2713 sizeof(struct ifreq))) 2714 ret = -EFAULT; 2715 } 2716 return ret; 2717 2718 /* 2719 * These ioctl calls: 2720 * - require superuser power. 2721 * - require strict serialization. 2722 * - return a value 2723 */ 2724 case SIOCGMIIPHY: 2725 case SIOCGMIIREG: 2726 case SIOCSIFNAME: 2727 if (!capable(CAP_NET_ADMIN)) 2728 return -EPERM; 2729 dev_load(ifr.ifr_name); 2730 rtnl_lock(); 2731 ret = dev_ifsioc(&ifr, cmd); 2732 rtnl_unlock(); 2733 if (!ret) { 2734 if (colon) 2735 *colon = ':'; 2736 if (copy_to_user(arg, &ifr, 2737 sizeof(struct ifreq))) 2738 ret = -EFAULT; 2739 } 2740 return ret; 2741 2742 /* 2743 * These ioctl calls: 2744 * - require superuser power. 2745 * - require strict serialization. 2746 * - do not return a value 2747 */ 2748 case SIOCSIFFLAGS: 2749 case SIOCSIFMETRIC: 2750 case SIOCSIFMTU: 2751 case SIOCSIFMAP: 2752 case SIOCSIFHWADDR: 2753 case SIOCSIFSLAVE: 2754 case SIOCADDMULTI: 2755 case SIOCDELMULTI: 2756 case SIOCSIFHWBROADCAST: 2757 case SIOCSIFTXQLEN: 2758 case SIOCSMIIREG: 2759 case SIOCBONDENSLAVE: 2760 case SIOCBONDRELEASE: 2761 case SIOCBONDSETHWADDR: 2762 case SIOCBONDCHANGEACTIVE: 2763 case SIOCBRADDIF: 2764 case SIOCBRDELIF: 2765 if (!capable(CAP_NET_ADMIN)) 2766 return -EPERM; 2767 /* fall through */ 2768 case SIOCBONDSLAVEINFOQUERY: 2769 case SIOCBONDINFOQUERY: 2770 dev_load(ifr.ifr_name); 2771 rtnl_lock(); 2772 ret = dev_ifsioc(&ifr, cmd); 2773 rtnl_unlock(); 2774 return ret; 2775 2776 case SIOCGIFMEM: 2777 /* Get the per device memory space. We can add this but 2778 * currently do not support it */ 2779 case SIOCSIFMEM: 2780 /* Set the per device memory buffer space. 2781 * Not applicable in our case */ 2782 case SIOCSIFLINK: 2783 return -EINVAL; 2784 2785 /* 2786 * Unknown or private ioctl. 2787 */ 2788 default: 2789 if (cmd == SIOCWANDEV || 2790 (cmd >= SIOCDEVPRIVATE && 2791 cmd <= SIOCDEVPRIVATE + 15)) { 2792 dev_load(ifr.ifr_name); 2793 rtnl_lock(); 2794 ret = dev_ifsioc(&ifr, cmd); 2795 rtnl_unlock(); 2796 if (!ret && copy_to_user(arg, &ifr, 2797 sizeof(struct ifreq))) 2798 ret = -EFAULT; 2799 return ret; 2800 } 2801 #ifdef CONFIG_WIRELESS_EXT 2802 /* Take care of Wireless Extensions */ 2803 if (cmd >= SIOCIWFIRST && cmd <= SIOCIWLAST) { 2804 /* If command is `set a parameter', or 2805 * `get the encoding parameters', check if 2806 * the user has the right to do it */ 2807 if (IW_IS_SET(cmd) || cmd == SIOCGIWENCODE 2808 || cmd == SIOCGIWENCODEEXT) { 2809 if (!capable(CAP_NET_ADMIN)) 2810 return -EPERM; 2811 } 2812 dev_load(ifr.ifr_name); 2813 rtnl_lock(); 2814 /* Follow me in net/core/wireless.c */ 2815 ret = wireless_process_ioctl(&ifr, cmd); 2816 rtnl_unlock(); 2817 if (IW_IS_GET(cmd) && 2818 copy_to_user(arg, &ifr, 2819 sizeof(struct ifreq))) 2820 ret = -EFAULT; 2821 return ret; 2822 } 2823 #endif /* CONFIG_WIRELESS_EXT */ 2824 return -EINVAL; 2825 } 2826 } 2827 2828 2829 /** 2830 * dev_new_index - allocate an ifindex 2831 * 2832 * Returns a suitable unique value for a new device interface 2833 * number. The caller must hold the rtnl semaphore or the 2834 * dev_base_lock to be sure it remains unique. 2835 */ 2836 static int dev_new_index(void) 2837 { 2838 static int ifindex; 2839 for (;;) { 2840 if (++ifindex <= 0) 2841 ifindex = 1; 2842 if (!__dev_get_by_index(ifindex)) 2843 return ifindex; 2844 } 2845 } 2846 2847 static int dev_boot_phase = 1; 2848 2849 /* Delayed registration/unregisteration */ 2850 static DEFINE_SPINLOCK(net_todo_list_lock); 2851 static struct list_head net_todo_list = LIST_HEAD_INIT(net_todo_list); 2852 2853 static inline void net_set_todo(struct net_device *dev) 2854 { 2855 spin_lock(&net_todo_list_lock); 2856 list_add_tail(&dev->todo_list, &net_todo_list); 2857 spin_unlock(&net_todo_list_lock); 2858 } 2859 2860 /** 2861 * register_netdevice - register a network device 2862 * @dev: device to register 2863 * 2864 * Take a completed network device structure and add it to the kernel 2865 * interfaces. A %NETDEV_REGISTER message is sent to the netdev notifier 2866 * chain. 0 is returned on success. A negative errno code is returned 2867 * on a failure to set up the device, or if the name is a duplicate. 2868 * 2869 * Callers must hold the rtnl semaphore. You may want 2870 * register_netdev() instead of this. 2871 * 2872 * BUGS: 2873 * The locking appears insufficient to guarantee two parallel registers 2874 * will not get the same name. 2875 */ 2876 2877 int register_netdevice(struct net_device *dev) 2878 { 2879 struct hlist_head *head; 2880 struct hlist_node *p; 2881 int ret; 2882 2883 BUG_ON(dev_boot_phase); 2884 ASSERT_RTNL(); 2885 2886 might_sleep(); 2887 2888 /* When net_device's are persistent, this will be fatal. */ 2889 BUG_ON(dev->reg_state != NETREG_UNINITIALIZED); 2890 2891 spin_lock_init(&dev->queue_lock); 2892 spin_lock_init(&dev->_xmit_lock); 2893 dev->xmit_lock_owner = -1; 2894 #ifdef CONFIG_NET_CLS_ACT 2895 spin_lock_init(&dev->ingress_lock); 2896 #endif 2897 2898 dev->iflink = -1; 2899 2900 /* Init, if this function is available */ 2901 if (dev->init) { 2902 ret = dev->init(dev); 2903 if (ret) { 2904 if (ret > 0) 2905 ret = -EIO; 2906 goto out; 2907 } 2908 } 2909 2910 if (!dev_valid_name(dev->name)) { 2911 ret = -EINVAL; 2912 goto out; 2913 } 2914 2915 dev->ifindex = dev_new_index(); 2916 if (dev->iflink == -1) 2917 dev->iflink = dev->ifindex; 2918 2919 /* Check for existence of name */ 2920 head = dev_name_hash(dev->name); 2921 hlist_for_each(p, head) { 2922 struct net_device *d 2923 = hlist_entry(p, struct net_device, name_hlist); 2924 if (!strncmp(d->name, dev->name, IFNAMSIZ)) { 2925 ret = -EEXIST; 2926 goto out; 2927 } 2928 } 2929 2930 /* Fix illegal SG+CSUM combinations. */ 2931 if ((dev->features & NETIF_F_SG) && 2932 !(dev->features & NETIF_F_ALL_CSUM)) { 2933 printk(KERN_NOTICE "%s: Dropping NETIF_F_SG since no checksum feature.\n", 2934 dev->name); 2935 dev->features &= ~NETIF_F_SG; 2936 } 2937 2938 /* TSO requires that SG is present as well. */ 2939 if ((dev->features & NETIF_F_TSO) && 2940 !(dev->features & NETIF_F_SG)) { 2941 printk(KERN_NOTICE "%s: Dropping NETIF_F_TSO since no SG feature.\n", 2942 dev->name); 2943 dev->features &= ~NETIF_F_TSO; 2944 } 2945 if (dev->features & NETIF_F_UFO) { 2946 if (!(dev->features & NETIF_F_HW_CSUM)) { 2947 printk(KERN_ERR "%s: Dropping NETIF_F_UFO since no " 2948 "NETIF_F_HW_CSUM feature.\n", 2949 dev->name); 2950 dev->features &= ~NETIF_F_UFO; 2951 } 2952 if (!(dev->features & NETIF_F_SG)) { 2953 printk(KERN_ERR "%s: Dropping NETIF_F_UFO since no " 2954 "NETIF_F_SG feature.\n", 2955 dev->name); 2956 dev->features &= ~NETIF_F_UFO; 2957 } 2958 } 2959 2960 /* 2961 * nil rebuild_header routine, 2962 * that should be never called and used as just bug trap. 2963 */ 2964 2965 if (!dev->rebuild_header) 2966 dev->rebuild_header = default_rebuild_header; 2967 2968 ret = netdev_register_sysfs(dev); 2969 if (ret) 2970 goto out; 2971 dev->reg_state = NETREG_REGISTERED; 2972 2973 /* 2974 * Default initial state at registry is that the 2975 * device is present. 2976 */ 2977 2978 set_bit(__LINK_STATE_PRESENT, &dev->state); 2979 2980 dev->next = NULL; 2981 dev_init_scheduler(dev); 2982 write_lock_bh(&dev_base_lock); 2983 *dev_tail = dev; 2984 dev_tail = &dev->next; 2985 hlist_add_head(&dev->name_hlist, head); 2986 hlist_add_head(&dev->index_hlist, dev_index_hash(dev->ifindex)); 2987 dev_hold(dev); 2988 write_unlock_bh(&dev_base_lock); 2989 2990 /* Notify protocols, that a new device appeared. */ 2991 raw_notifier_call_chain(&netdev_chain, NETDEV_REGISTER, dev); 2992 2993 ret = 0; 2994 2995 out: 2996 return ret; 2997 } 2998 2999 /** 3000 * register_netdev - register a network device 3001 * @dev: device to register 3002 * 3003 * Take a completed network device structure and add it to the kernel 3004 * interfaces. A %NETDEV_REGISTER message is sent to the netdev notifier 3005 * chain. 0 is returned on success. A negative errno code is returned 3006 * on a failure to set up the device, or if the name is a duplicate. 3007 * 3008 * This is a wrapper around register_netdev that takes the rtnl semaphore 3009 * and expands the device name if you passed a format string to 3010 * alloc_netdev. 3011 */ 3012 int register_netdev(struct net_device *dev) 3013 { 3014 int err; 3015 3016 rtnl_lock(); 3017 3018 /* 3019 * If the name is a format string the caller wants us to do a 3020 * name allocation. 3021 */ 3022 if (strchr(dev->name, '%')) { 3023 err = dev_alloc_name(dev, dev->name); 3024 if (err < 0) 3025 goto out; 3026 } 3027 3028 err = register_netdevice(dev); 3029 out: 3030 rtnl_unlock(); 3031 return err; 3032 } 3033 EXPORT_SYMBOL(register_netdev); 3034 3035 /* 3036 * netdev_wait_allrefs - wait until all references are gone. 3037 * 3038 * This is called when unregistering network devices. 3039 * 3040 * Any protocol or device that holds a reference should register 3041 * for netdevice notification, and cleanup and put back the 3042 * reference if they receive an UNREGISTER event. 3043 * We can get stuck here if buggy protocols don't correctly 3044 * call dev_put. 3045 */ 3046 static void netdev_wait_allrefs(struct net_device *dev) 3047 { 3048 unsigned long rebroadcast_time, warning_time; 3049 3050 rebroadcast_time = warning_time = jiffies; 3051 while (atomic_read(&dev->refcnt) != 0) { 3052 if (time_after(jiffies, rebroadcast_time + 1 * HZ)) { 3053 rtnl_lock(); 3054 3055 /* Rebroadcast unregister notification */ 3056 raw_notifier_call_chain(&netdev_chain, 3057 NETDEV_UNREGISTER, dev); 3058 3059 if (test_bit(__LINK_STATE_LINKWATCH_PENDING, 3060 &dev->state)) { 3061 /* We must not have linkwatch events 3062 * pending on unregister. If this 3063 * happens, we simply run the queue 3064 * unscheduled, resulting in a noop 3065 * for this device. 3066 */ 3067 linkwatch_run_queue(); 3068 } 3069 3070 __rtnl_unlock(); 3071 3072 rebroadcast_time = jiffies; 3073 } 3074 3075 msleep(250); 3076 3077 if (time_after(jiffies, warning_time + 10 * HZ)) { 3078 printk(KERN_EMERG "unregister_netdevice: " 3079 "waiting for %s to become free. Usage " 3080 "count = %d\n", 3081 dev->name, atomic_read(&dev->refcnt)); 3082 warning_time = jiffies; 3083 } 3084 } 3085 } 3086 3087 /* The sequence is: 3088 * 3089 * rtnl_lock(); 3090 * ... 3091 * register_netdevice(x1); 3092 * register_netdevice(x2); 3093 * ... 3094 * unregister_netdevice(y1); 3095 * unregister_netdevice(y2); 3096 * ... 3097 * rtnl_unlock(); 3098 * free_netdev(y1); 3099 * free_netdev(y2); 3100 * 3101 * We are invoked by rtnl_unlock() after it drops the semaphore. 3102 * This allows us to deal with problems: 3103 * 1) We can delete sysfs objects which invoke hotplug 3104 * without deadlocking with linkwatch via keventd. 3105 * 2) Since we run with the RTNL semaphore not held, we can sleep 3106 * safely in order to wait for the netdev refcnt to drop to zero. 3107 */ 3108 static DEFINE_MUTEX(net_todo_run_mutex); 3109 void netdev_run_todo(void) 3110 { 3111 struct list_head list; 3112 3113 /* Need to guard against multiple cpu's getting out of order. */ 3114 mutex_lock(&net_todo_run_mutex); 3115 3116 /* Not safe to do outside the semaphore. We must not return 3117 * until all unregister events invoked by the local processor 3118 * have been completed (either by this todo run, or one on 3119 * another cpu). 3120 */ 3121 if (list_empty(&net_todo_list)) 3122 goto out; 3123 3124 /* Snapshot list, allow later requests */ 3125 spin_lock(&net_todo_list_lock); 3126 list_replace_init(&net_todo_list, &list); 3127 spin_unlock(&net_todo_list_lock); 3128 3129 while (!list_empty(&list)) { 3130 struct net_device *dev 3131 = list_entry(list.next, struct net_device, todo_list); 3132 list_del(&dev->todo_list); 3133 3134 if (unlikely(dev->reg_state != NETREG_UNREGISTERING)) { 3135 printk(KERN_ERR "network todo '%s' but state %d\n", 3136 dev->name, dev->reg_state); 3137 dump_stack(); 3138 continue; 3139 } 3140 3141 netdev_unregister_sysfs(dev); 3142 dev->reg_state = NETREG_UNREGISTERED; 3143 3144 netdev_wait_allrefs(dev); 3145 3146 /* paranoia */ 3147 BUG_ON(atomic_read(&dev->refcnt)); 3148 BUG_TRAP(!dev->ip_ptr); 3149 BUG_TRAP(!dev->ip6_ptr); 3150 BUG_TRAP(!dev->dn_ptr); 3151 3152 /* It must be the very last action, 3153 * after this 'dev' may point to freed up memory. 3154 */ 3155 if (dev->destructor) 3156 dev->destructor(dev); 3157 } 3158 3159 out: 3160 mutex_unlock(&net_todo_run_mutex); 3161 } 3162 3163 /** 3164 * alloc_netdev - allocate network device 3165 * @sizeof_priv: size of private data to allocate space for 3166 * @name: device name format string 3167 * @setup: callback to initialize device 3168 * 3169 * Allocates a struct net_device with private data area for driver use 3170 * and performs basic initialization. 3171 */ 3172 struct net_device *alloc_netdev(int sizeof_priv, const char *name, 3173 void (*setup)(struct net_device *)) 3174 { 3175 void *p; 3176 struct net_device *dev; 3177 int alloc_size; 3178 3179 BUG_ON(strlen(name) >= sizeof(dev->name)); 3180 3181 /* ensure 32-byte alignment of both the device and private area */ 3182 alloc_size = (sizeof(*dev) + NETDEV_ALIGN_CONST) & ~NETDEV_ALIGN_CONST; 3183 alloc_size += sizeof_priv + NETDEV_ALIGN_CONST; 3184 3185 p = kzalloc(alloc_size, GFP_KERNEL); 3186 if (!p) { 3187 printk(KERN_ERR "alloc_netdev: Unable to allocate device.\n"); 3188 return NULL; 3189 } 3190 3191 dev = (struct net_device *) 3192 (((long)p + NETDEV_ALIGN_CONST) & ~NETDEV_ALIGN_CONST); 3193 dev->padded = (char *)dev - (char *)p; 3194 3195 if (sizeof_priv) 3196 dev->priv = netdev_priv(dev); 3197 3198 setup(dev); 3199 strcpy(dev->name, name); 3200 return dev; 3201 } 3202 EXPORT_SYMBOL(alloc_netdev); 3203 3204 /** 3205 * free_netdev - free network device 3206 * @dev: device 3207 * 3208 * This function does the last stage of destroying an allocated device 3209 * interface. The reference to the device object is released. 3210 * If this is the last reference then it will be freed. 3211 */ 3212 void free_netdev(struct net_device *dev) 3213 { 3214 #ifdef CONFIG_SYSFS 3215 /* Compatibility with error handling in drivers */ 3216 if (dev->reg_state == NETREG_UNINITIALIZED) { 3217 kfree((char *)dev - dev->padded); 3218 return; 3219 } 3220 3221 BUG_ON(dev->reg_state != NETREG_UNREGISTERED); 3222 dev->reg_state = NETREG_RELEASED; 3223 3224 /* will free via device release */ 3225 put_device(&dev->dev); 3226 #else 3227 kfree((char *)dev - dev->padded); 3228 #endif 3229 } 3230 3231 /* Synchronize with packet receive processing. */ 3232 void synchronize_net(void) 3233 { 3234 might_sleep(); 3235 synchronize_rcu(); 3236 } 3237 3238 /** 3239 * unregister_netdevice - remove device from the kernel 3240 * @dev: device 3241 * 3242 * This function shuts down a device interface and removes it 3243 * from the kernel tables. On success 0 is returned, on a failure 3244 * a negative errno code is returned. 3245 * 3246 * Callers must hold the rtnl semaphore. You may want 3247 * unregister_netdev() instead of this. 3248 */ 3249 3250 int unregister_netdevice(struct net_device *dev) 3251 { 3252 struct net_device *d, **dp; 3253 3254 BUG_ON(dev_boot_phase); 3255 ASSERT_RTNL(); 3256 3257 /* Some devices call without registering for initialization unwind. */ 3258 if (dev->reg_state == NETREG_UNINITIALIZED) { 3259 printk(KERN_DEBUG "unregister_netdevice: device %s/%p never " 3260 "was registered\n", dev->name, dev); 3261 return -ENODEV; 3262 } 3263 3264 BUG_ON(dev->reg_state != NETREG_REGISTERED); 3265 3266 /* If device is running, close it first. */ 3267 if (dev->flags & IFF_UP) 3268 dev_close(dev); 3269 3270 /* And unlink it from device chain. */ 3271 for (dp = &dev_base; (d = *dp) != NULL; dp = &d->next) { 3272 if (d == dev) { 3273 write_lock_bh(&dev_base_lock); 3274 hlist_del(&dev->name_hlist); 3275 hlist_del(&dev->index_hlist); 3276 if (dev_tail == &dev->next) 3277 dev_tail = dp; 3278 *dp = d->next; 3279 write_unlock_bh(&dev_base_lock); 3280 break; 3281 } 3282 } 3283 if (!d) { 3284 printk(KERN_ERR "unregister net_device: '%s' not found\n", 3285 dev->name); 3286 return -ENODEV; 3287 } 3288 3289 dev->reg_state = NETREG_UNREGISTERING; 3290 3291 synchronize_net(); 3292 3293 /* Shutdown queueing discipline. */ 3294 dev_shutdown(dev); 3295 3296 3297 /* Notify protocols, that we are about to destroy 3298 this device. They should clean all the things. 3299 */ 3300 raw_notifier_call_chain(&netdev_chain, NETDEV_UNREGISTER, dev); 3301 3302 /* 3303 * Flush the multicast chain 3304 */ 3305 dev_mc_discard(dev); 3306 3307 if (dev->uninit) 3308 dev->uninit(dev); 3309 3310 /* Notifier chain MUST detach us from master device. */ 3311 BUG_TRAP(!dev->master); 3312 3313 /* Finish processing unregister after unlock */ 3314 net_set_todo(dev); 3315 3316 synchronize_net(); 3317 3318 dev_put(dev); 3319 return 0; 3320 } 3321 3322 /** 3323 * unregister_netdev - remove device from the kernel 3324 * @dev: device 3325 * 3326 * This function shuts down a device interface and removes it 3327 * from the kernel tables. On success 0 is returned, on a failure 3328 * a negative errno code is returned. 3329 * 3330 * This is just a wrapper for unregister_netdevice that takes 3331 * the rtnl semaphore. In general you want to use this and not 3332 * unregister_netdevice. 3333 */ 3334 void unregister_netdev(struct net_device *dev) 3335 { 3336 rtnl_lock(); 3337 unregister_netdevice(dev); 3338 rtnl_unlock(); 3339 } 3340 3341 EXPORT_SYMBOL(unregister_netdev); 3342 3343 static int dev_cpu_callback(struct notifier_block *nfb, 3344 unsigned long action, 3345 void *ocpu) 3346 { 3347 struct sk_buff **list_skb; 3348 struct net_device **list_net; 3349 struct sk_buff *skb; 3350 unsigned int cpu, oldcpu = (unsigned long)ocpu; 3351 struct softnet_data *sd, *oldsd; 3352 3353 if (action != CPU_DEAD) 3354 return NOTIFY_OK; 3355 3356 local_irq_disable(); 3357 cpu = smp_processor_id(); 3358 sd = &per_cpu(softnet_data, cpu); 3359 oldsd = &per_cpu(softnet_data, oldcpu); 3360 3361 /* Find end of our completion_queue. */ 3362 list_skb = &sd->completion_queue; 3363 while (*list_skb) 3364 list_skb = &(*list_skb)->next; 3365 /* Append completion queue from offline CPU. */ 3366 *list_skb = oldsd->completion_queue; 3367 oldsd->completion_queue = NULL; 3368 3369 /* Find end of our output_queue. */ 3370 list_net = &sd->output_queue; 3371 while (*list_net) 3372 list_net = &(*list_net)->next_sched; 3373 /* Append output queue from offline CPU. */ 3374 *list_net = oldsd->output_queue; 3375 oldsd->output_queue = NULL; 3376 3377 raise_softirq_irqoff(NET_TX_SOFTIRQ); 3378 local_irq_enable(); 3379 3380 /* Process offline CPU's input_pkt_queue */ 3381 while ((skb = __skb_dequeue(&oldsd->input_pkt_queue))) 3382 netif_rx(skb); 3383 3384 return NOTIFY_OK; 3385 } 3386 3387 #ifdef CONFIG_NET_DMA 3388 /** 3389 * net_dma_rebalance - 3390 * This is called when the number of channels allocated to the net_dma_client 3391 * changes. The net_dma_client tries to have one DMA channel per CPU. 3392 */ 3393 static void net_dma_rebalance(void) 3394 { 3395 unsigned int cpu, i, n; 3396 struct dma_chan *chan; 3397 3398 if (net_dma_count == 0) { 3399 for_each_online_cpu(cpu) 3400 rcu_assign_pointer(per_cpu(softnet_data, cpu).net_dma, NULL); 3401 return; 3402 } 3403 3404 i = 0; 3405 cpu = first_cpu(cpu_online_map); 3406 3407 rcu_read_lock(); 3408 list_for_each_entry(chan, &net_dma_client->channels, client_node) { 3409 n = ((num_online_cpus() / net_dma_count) 3410 + (i < (num_online_cpus() % net_dma_count) ? 1 : 0)); 3411 3412 while(n) { 3413 per_cpu(softnet_data, cpu).net_dma = chan; 3414 cpu = next_cpu(cpu, cpu_online_map); 3415 n--; 3416 } 3417 i++; 3418 } 3419 rcu_read_unlock(); 3420 } 3421 3422 /** 3423 * netdev_dma_event - event callback for the net_dma_client 3424 * @client: should always be net_dma_client 3425 * @chan: DMA channel for the event 3426 * @event: event type 3427 */ 3428 static void netdev_dma_event(struct dma_client *client, struct dma_chan *chan, 3429 enum dma_event event) 3430 { 3431 spin_lock(&net_dma_event_lock); 3432 switch (event) { 3433 case DMA_RESOURCE_ADDED: 3434 net_dma_count++; 3435 net_dma_rebalance(); 3436 break; 3437 case DMA_RESOURCE_REMOVED: 3438 net_dma_count--; 3439 net_dma_rebalance(); 3440 break; 3441 default: 3442 break; 3443 } 3444 spin_unlock(&net_dma_event_lock); 3445 } 3446 3447 /** 3448 * netdev_dma_regiser - register the networking subsystem as a DMA client 3449 */ 3450 static int __init netdev_dma_register(void) 3451 { 3452 spin_lock_init(&net_dma_event_lock); 3453 net_dma_client = dma_async_client_register(netdev_dma_event); 3454 if (net_dma_client == NULL) 3455 return -ENOMEM; 3456 3457 dma_async_client_chan_request(net_dma_client, num_online_cpus()); 3458 return 0; 3459 } 3460 3461 #else 3462 static int __init netdev_dma_register(void) { return -ENODEV; } 3463 #endif /* CONFIG_NET_DMA */ 3464 3465 /* 3466 * Initialize the DEV module. At boot time this walks the device list and 3467 * unhooks any devices that fail to initialise (normally hardware not 3468 * present) and leaves us with a valid list of present and active devices. 3469 * 3470 */ 3471 3472 /* 3473 * This is called single threaded during boot, so no need 3474 * to take the rtnl semaphore. 3475 */ 3476 static int __init net_dev_init(void) 3477 { 3478 int i, rc = -ENOMEM; 3479 3480 BUG_ON(!dev_boot_phase); 3481 3482 if (dev_proc_init()) 3483 goto out; 3484 3485 if (netdev_sysfs_init()) 3486 goto out; 3487 3488 INIT_LIST_HEAD(&ptype_all); 3489 for (i = 0; i < 16; i++) 3490 INIT_LIST_HEAD(&ptype_base[i]); 3491 3492 for (i = 0; i < ARRAY_SIZE(dev_name_head); i++) 3493 INIT_HLIST_HEAD(&dev_name_head[i]); 3494 3495 for (i = 0; i < ARRAY_SIZE(dev_index_head); i++) 3496 INIT_HLIST_HEAD(&dev_index_head[i]); 3497 3498 /* 3499 * Initialise the packet receive queues. 3500 */ 3501 3502 for_each_possible_cpu(i) { 3503 struct softnet_data *queue; 3504 3505 queue = &per_cpu(softnet_data, i); 3506 skb_queue_head_init(&queue->input_pkt_queue); 3507 queue->completion_queue = NULL; 3508 INIT_LIST_HEAD(&queue->poll_list); 3509 set_bit(__LINK_STATE_START, &queue->backlog_dev.state); 3510 queue->backlog_dev.weight = weight_p; 3511 queue->backlog_dev.poll = process_backlog; 3512 atomic_set(&queue->backlog_dev.refcnt, 1); 3513 } 3514 3515 netdev_dma_register(); 3516 3517 dev_boot_phase = 0; 3518 3519 open_softirq(NET_TX_SOFTIRQ, net_tx_action, NULL); 3520 open_softirq(NET_RX_SOFTIRQ, net_rx_action, NULL); 3521 3522 hotcpu_notifier(dev_cpu_callback, 0); 3523 dst_init(); 3524 dev_mcast_init(); 3525 rc = 0; 3526 out: 3527 return rc; 3528 } 3529 3530 subsys_initcall(net_dev_init); 3531 3532 EXPORT_SYMBOL(__dev_get_by_index); 3533 EXPORT_SYMBOL(__dev_get_by_name); 3534 EXPORT_SYMBOL(__dev_remove_pack); 3535 EXPORT_SYMBOL(dev_valid_name); 3536 EXPORT_SYMBOL(dev_add_pack); 3537 EXPORT_SYMBOL(dev_alloc_name); 3538 EXPORT_SYMBOL(dev_close); 3539 EXPORT_SYMBOL(dev_get_by_flags); 3540 EXPORT_SYMBOL(dev_get_by_index); 3541 EXPORT_SYMBOL(dev_get_by_name); 3542 EXPORT_SYMBOL(dev_open); 3543 EXPORT_SYMBOL(dev_queue_xmit); 3544 EXPORT_SYMBOL(dev_remove_pack); 3545 EXPORT_SYMBOL(dev_set_allmulti); 3546 EXPORT_SYMBOL(dev_set_promiscuity); 3547 EXPORT_SYMBOL(dev_change_flags); 3548 EXPORT_SYMBOL(dev_set_mtu); 3549 EXPORT_SYMBOL(dev_set_mac_address); 3550 EXPORT_SYMBOL(free_netdev); 3551 EXPORT_SYMBOL(netdev_boot_setup_check); 3552 EXPORT_SYMBOL(netdev_set_master); 3553 EXPORT_SYMBOL(netdev_state_change); 3554 EXPORT_SYMBOL(netif_receive_skb); 3555 EXPORT_SYMBOL(netif_rx); 3556 EXPORT_SYMBOL(register_gifconf); 3557 EXPORT_SYMBOL(register_netdevice); 3558 EXPORT_SYMBOL(register_netdevice_notifier); 3559 EXPORT_SYMBOL(skb_checksum_help); 3560 EXPORT_SYMBOL(synchronize_net); 3561 EXPORT_SYMBOL(unregister_netdevice); 3562 EXPORT_SYMBOL(unregister_netdevice_notifier); 3563 EXPORT_SYMBOL(net_enable_timestamp); 3564 EXPORT_SYMBOL(net_disable_timestamp); 3565 EXPORT_SYMBOL(dev_get_flags); 3566 3567 #if defined(CONFIG_BRIDGE) || defined(CONFIG_BRIDGE_MODULE) 3568 EXPORT_SYMBOL(br_handle_frame_hook); 3569 EXPORT_SYMBOL(br_fdb_get_hook); 3570 EXPORT_SYMBOL(br_fdb_put_hook); 3571 #endif 3572 3573 #ifdef CONFIG_KMOD 3574 EXPORT_SYMBOL(dev_load); 3575 #endif 3576 3577 EXPORT_PER_CPU_SYMBOL(softnet_data); 3578