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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 <linux/divert.h> 102#include <net/dst.h> 103#include <net/pkt_sched.h> 104#include <net/checksum.h> 105#include <linux/highmem.h> 106#include <linux/init.h> 107#include <linux/kmod.h> 108#include <linux/module.h> 109#include <linux/kallsyms.h> 110#include <linux/netpoll.h> 111#include <linux/rcupdate.h> 112#include <linux/delay.h> 113#include <linux/wireless.h> 114#include <net/iw_handler.h> 115#include <asm/current.h> 116#include <linux/audit.h> 117#include <linux/dmaengine.h> 118#include <linux/err.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 148static DEFINE_SPINLOCK(ptype_lock); 149static struct list_head ptype_base[16]; /* 16 way hashed list */ 150static struct list_head ptype_all; /* Taps */ 151 152#ifdef CONFIG_NET_DMA 153static struct dma_client *net_dma_client; 154static unsigned int net_dma_count; 155static 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 */ 177struct net_device *dev_base; 178static struct net_device **dev_tail = &dev_base; 179DEFINE_RWLOCK(dev_base_lock); 180 181EXPORT_SYMBOL(dev_base); 182EXPORT_SYMBOL(dev_base_lock); 183 184#define NETDEV_HASHBITS 8 185static struct hlist_head dev_name_head[1<<NETDEV_HASHBITS]; 186static struct hlist_head dev_index_head[1<<NETDEV_HASHBITS]; 187 188static 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 194static 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 203static 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 */ 209DEFINE_PER_CPU(struct softnet_data, softnet_data) = { NULL }; 210 211#ifdef CONFIG_SYSFS 212extern int netdev_sysfs_init(void); 213extern int netdev_register_sysfs(struct net_device *); 214extern 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 232static 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 263void 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 */ 291void __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); 312out: 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 */ 327void 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 */ 341static 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 */ 352static 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 */ 379int 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 */ 408unsigned 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 */ 432int __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 475struct 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 499struct 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 522struct 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 546struct 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 572struct 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 585EXPORT_SYMBOL(dev_getbyhwaddr); 586 587struct 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 602EXPORT_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 615struct 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 636 */ 637int dev_valid_name(const char *name) 638{ 639 return !(*name == '\0' 640 || !strcmp(name, ".") 641 || !strcmp(name, "..") 642 || strchr(name, '/')); 643} 644 645/** 646 * dev_alloc_name - allocate a name for a device 647 * @dev: device 648 * @name: name format string 649 * 650 * Passed a format string - eg "lt%d" it will try and find a suitable 651 * id. It scans list of devices to build up a free map, then chooses 652 * the first empty slot. The caller must hold the dev_base or rtnl lock 653 * while allocating the name and adding the device in order to avoid 654 * duplicates. 655 * Limited to bits_per_byte * page size devices (ie 32K on most platforms). 656 * Returns the number of the unit assigned or a negative errno code. 657 */ 658 659int dev_alloc_name(struct net_device *dev, const char *name) 660{ 661 int i = 0; 662 char buf[IFNAMSIZ]; 663 const char *p; 664 const int max_netdevices = 8*PAGE_SIZE; 665 long *inuse; 666 struct net_device *d; 667 668 p = strnchr(name, IFNAMSIZ-1, '%'); 669 if (p) { 670 /* 671 * Verify the string as this thing may have come from 672 * the user. There must be either one "%d" and no other "%" 673 * characters. 674 */ 675 if (p[1] != 'd' || strchr(p + 2, '%')) 676 return -EINVAL; 677 678 /* Use one page as a bit array of possible slots */ 679 inuse = (long *) get_zeroed_page(GFP_ATOMIC); 680 if (!inuse) 681 return -ENOMEM; 682 683 for (d = dev_base; d; d = d->next) { 684 if (!sscanf(d->name, name, &i)) 685 continue; 686 if (i < 0 || i >= max_netdevices) 687 continue; 688 689 /* avoid cases where sscanf is not exact inverse of printf */ 690 snprintf(buf, sizeof(buf), name, i); 691 if (!strncmp(buf, d->name, IFNAMSIZ)) 692 set_bit(i, inuse); 693 } 694 695 i = find_first_zero_bit(inuse, max_netdevices); 696 free_page((unsigned long) inuse); 697 } 698 699 snprintf(buf, sizeof(buf), name, i); 700 if (!__dev_get_by_name(buf)) { 701 strlcpy(dev->name, buf, IFNAMSIZ); 702 return i; 703 } 704 705 /* It is possible to run out of possible slots 706 * when the name is long and there isn't enough space left 707 * for the digits, or if all bits are used. 708 */ 709 return -ENFILE; 710} 711 712 713/** 714 * dev_change_name - change name of a device 715 * @dev: device 716 * @newname: name (or format string) must be at least IFNAMSIZ 717 * 718 * Change name of a device, can pass format strings "eth%d". 719 * for wildcarding. 720 */ 721int dev_change_name(struct net_device *dev, char *newname) 722{ 723 int err = 0; 724 725 ASSERT_RTNL(); 726 727 if (dev->flags & IFF_UP) 728 return -EBUSY; 729 730 if (!dev_valid_name(newname)) 731 return -EINVAL; 732 733 if (strchr(newname, '%')) { 734 err = dev_alloc_name(dev, newname); 735 if (err < 0) 736 return err; 737 strcpy(newname, dev->name); 738 } 739 else if (__dev_get_by_name(newname)) 740 return -EEXIST; 741 else 742 strlcpy(dev->name, newname, IFNAMSIZ); 743 744 err = class_device_rename(&dev->class_dev, dev->name); 745 if (!err) { 746 hlist_del(&dev->name_hlist); 747 hlist_add_head(&dev->name_hlist, dev_name_hash(dev->name)); 748 raw_notifier_call_chain(&netdev_chain, 749 NETDEV_CHANGENAME, dev); 750 } 751 752 return err; 753} 754 755/** 756 * netdev_features_change - device changes features 757 * @dev: device to cause notification 758 * 759 * Called to indicate a device has changed features. 760 */ 761void netdev_features_change(struct net_device *dev) 762{ 763 raw_notifier_call_chain(&netdev_chain, NETDEV_FEAT_CHANGE, dev); 764} 765EXPORT_SYMBOL(netdev_features_change); 766 767/** 768 * netdev_state_change - device changes state 769 * @dev: device to cause notification 770 * 771 * Called to indicate a device has changed state. This function calls 772 * the notifier chains for netdev_chain and sends a NEWLINK message 773 * to the routing socket. 774 */ 775void netdev_state_change(struct net_device *dev) 776{ 777 if (dev->flags & IFF_UP) { 778 raw_notifier_call_chain(&netdev_chain, 779 NETDEV_CHANGE, dev); 780 rtmsg_ifinfo(RTM_NEWLINK, dev, 0); 781 } 782} 783 784/** 785 * dev_load - load a network module 786 * @name: name of interface 787 * 788 * If a network interface is not present and the process has suitable 789 * privileges this function loads the module. If module loading is not 790 * available in this kernel then it becomes a nop. 791 */ 792 793void dev_load(const char *name) 794{ 795 struct net_device *dev; 796 797 read_lock(&dev_base_lock); 798 dev = __dev_get_by_name(name); 799 read_unlock(&dev_base_lock); 800 801 if (!dev && capable(CAP_SYS_MODULE)) 802 request_module("%s", name); 803} 804 805static int default_rebuild_header(struct sk_buff *skb) 806{ 807 printk(KERN_DEBUG "%s: default_rebuild_header called -- BUG!\n", 808 skb->dev ? skb->dev->name : "NULL!!!"); 809 kfree_skb(skb); 810 return 1; 811} 812 813 814/** 815 * dev_open - prepare an interface for use. 816 * @dev: device to open 817 * 818 * Takes a device from down to up state. The device's private open 819 * function is invoked and then the multicast lists are loaded. Finally 820 * the device is moved into the up state and a %NETDEV_UP message is 821 * sent to the netdev notifier chain. 822 * 823 * Calling this function on an active interface is a nop. On a failure 824 * a negative errno code is returned. 825 */ 826int dev_open(struct net_device *dev) 827{ 828 int ret = 0; 829 830 /* 831 * Is it already up? 832 */ 833 834 if (dev->flags & IFF_UP) 835 return 0; 836 837 /* 838 * Is it even present? 839 */ 840 if (!netif_device_present(dev)) 841 return -ENODEV; 842 843 /* 844 * Call device private open method 845 */ 846 set_bit(__LINK_STATE_START, &dev->state); 847 if (dev->open) { 848 ret = dev->open(dev); 849 if (ret) 850 clear_bit(__LINK_STATE_START, &dev->state); 851 } 852 853 /* 854 * If it went open OK then: 855 */ 856 857 if (!ret) { 858 /* 859 * Set the flags. 860 */ 861 dev->flags |= IFF_UP; 862 863 /* 864 * Initialize multicasting status 865 */ 866 dev_mc_upload(dev); 867 868 /* 869 * Wakeup transmit queue engine 870 */ 871 dev_activate(dev); 872 873 /* 874 * ... and announce new interface. 875 */ 876 raw_notifier_call_chain(&netdev_chain, NETDEV_UP, dev); 877 } 878 return ret; 879} 880 881/** 882 * dev_close - shutdown an interface. 883 * @dev: device to shutdown 884 * 885 * This function moves an active device into down state. A 886 * %NETDEV_GOING_DOWN is sent to the netdev notifier chain. The device 887 * is then deactivated and finally a %NETDEV_DOWN is sent to the notifier 888 * chain. 889 */ 890int dev_close(struct net_device *dev) 891{ 892 if (!(dev->flags & IFF_UP)) 893 return 0; 894 895 /* 896 * Tell people we are going down, so that they can 897 * prepare to death, when device is still operating. 898 */ 899 raw_notifier_call_chain(&netdev_chain, NETDEV_GOING_DOWN, dev); 900 901 dev_deactivate(dev); 902 903 clear_bit(__LINK_STATE_START, &dev->state); 904 905 /* Synchronize to scheduled poll. We cannot touch poll list, 906 * it can be even on different cpu. So just clear netif_running(), 907 * and wait when poll really will happen. Actually, the best place 908 * for this is inside dev->stop() after device stopped its irq 909 * engine, but this requires more changes in devices. */ 910 911 smp_mb__after_clear_bit(); /* Commit netif_running(). */ 912 while (test_bit(__LINK_STATE_RX_SCHED, &dev->state)) { 913 /* No hurry. */ 914 msleep(1); 915 } 916 917 /* 918 * Call the device specific close. This cannot fail. 919 * Only if device is UP 920 * 921 * We allow it to be called even after a DETACH hot-plug 922 * event. 923 */ 924 if (dev->stop) 925 dev->stop(dev); 926 927 /* 928 * Device is now down. 929 */ 930 931 dev->flags &= ~IFF_UP; 932 933 /* 934 * Tell people we are down 935 */ 936 raw_notifier_call_chain(&netdev_chain, NETDEV_DOWN, dev); 937 938 return 0; 939} 940 941 942/* 943 * Device change register/unregister. These are not inline or static 944 * as we export them to the world. 945 */ 946 947/** 948 * register_netdevice_notifier - register a network notifier block 949 * @nb: notifier 950 * 951 * Register a notifier to be called when network device events occur. 952 * The notifier passed is linked into the kernel structures and must 953 * not be reused until it has been unregistered. A negative errno code 954 * is returned on a failure. 955 * 956 * When registered all registration and up events are replayed 957 * to the new notifier to allow device to have a race free 958 * view of the network device list. 959 */ 960 961int register_netdevice_notifier(struct notifier_block *nb) 962{ 963 struct net_device *dev; 964 int err; 965 966 rtnl_lock(); 967 err = raw_notifier_chain_register(&netdev_chain, nb); 968 if (!err) { 969 for (dev = dev_base; dev; dev = dev->next) { 970 nb->notifier_call(nb, NETDEV_REGISTER, dev); 971 972 if (dev->flags & IFF_UP) 973 nb->notifier_call(nb, NETDEV_UP, dev); 974 } 975 } 976 rtnl_unlock(); 977 return err; 978} 979 980/** 981 * unregister_netdevice_notifier - unregister a network notifier block 982 * @nb: notifier 983 * 984 * Unregister a notifier previously registered by 985 * register_netdevice_notifier(). The notifier is unlinked into the 986 * kernel structures and may then be reused. A negative errno code 987 * is returned on a failure. 988 */ 989 990int unregister_netdevice_notifier(struct notifier_block *nb) 991{ 992 int err; 993 994 rtnl_lock(); 995 err = raw_notifier_chain_unregister(&netdev_chain, nb); 996 rtnl_unlock(); 997 return err; 998} 999 1000/** 1001 * call_netdevice_notifiers - call all network notifier blocks 1002 * @val: value passed unmodified to notifier function 1003 * @v: pointer passed unmodified to notifier function 1004 * 1005 * Call all network notifier blocks. Parameters and return value 1006 * are as for raw_notifier_call_chain(). 1007 */ 1008 1009int call_netdevice_notifiers(unsigned long val, void *v) 1010{ 1011 return raw_notifier_call_chain(&netdev_chain, val, v); 1012} 1013 1014/* When > 0 there are consumers of rx skb time stamps */ 1015static atomic_t netstamp_needed = ATOMIC_INIT(0); 1016 1017void net_enable_timestamp(void) 1018{ 1019 atomic_inc(&netstamp_needed); 1020} 1021 1022void net_disable_timestamp(void) 1023{ 1024 atomic_dec(&netstamp_needed); 1025} 1026 1027void __net_timestamp(struct sk_buff *skb) 1028{ 1029 struct timeval tv; 1030 1031 do_gettimeofday(&tv); 1032 skb_set_timestamp(skb, &tv); 1033} 1034EXPORT_SYMBOL(__net_timestamp); 1035 1036static inline void net_timestamp(struct sk_buff *skb) 1037{ 1038 if (atomic_read(&netstamp_needed)) 1039 __net_timestamp(skb); 1040 else { 1041 skb->tstamp.off_sec = 0; 1042 skb->tstamp.off_usec = 0; 1043 } 1044} 1045 1046/* 1047 * Support routine. Sends outgoing frames to any network 1048 * taps currently in use. 1049 */ 1050 1051static void dev_queue_xmit_nit(struct sk_buff *skb, struct net_device *dev) 1052{ 1053 struct packet_type *ptype; 1054 1055 net_timestamp(skb); 1056 1057 rcu_read_lock(); 1058 list_for_each_entry_rcu(ptype, &ptype_all, list) { 1059 /* Never send packets back to the socket 1060 * they originated from - MvS (miquels@drinkel.ow.org) 1061 */ 1062 if ((ptype->dev == dev || !ptype->dev) && 1063 (ptype->af_packet_priv == NULL || 1064 (struct sock *)ptype->af_packet_priv != skb->sk)) { 1065 struct sk_buff *skb2= skb_clone(skb, GFP_ATOMIC); 1066 if (!skb2) 1067 break; 1068 1069 /* skb->nh should be correctly 1070 set by sender, so that the second statement is 1071 just protection against buggy protocols. 1072 */ 1073 skb2->mac.raw = skb2->data; 1074 1075 if (skb2->nh.raw < skb2->data || 1076 skb2->nh.raw > skb2->tail) { 1077 if (net_ratelimit()) 1078 printk(KERN_CRIT "protocol %04x is " 1079 "buggy, dev %s\n", 1080 skb2->protocol, dev->name); 1081 skb2->nh.raw = skb2->data; 1082 } 1083 1084 skb2->h.raw = skb2->nh.raw; 1085 skb2->pkt_type = PACKET_OUTGOING; 1086 ptype->func(skb2, skb->dev, ptype, skb->dev); 1087 } 1088 } 1089 rcu_read_unlock(); 1090} 1091 1092 1093void __netif_schedule(struct net_device *dev) 1094{ 1095 if (!test_and_set_bit(__LINK_STATE_SCHED, &dev->state)) { 1096 unsigned long flags; 1097 struct softnet_data *sd; 1098 1099 local_irq_save(flags); 1100 sd = &__get_cpu_var(softnet_data); 1101 dev->next_sched = sd->output_queue; 1102 sd->output_queue = dev; 1103 raise_softirq_irqoff(NET_TX_SOFTIRQ); 1104 local_irq_restore(flags); 1105 } 1106} 1107EXPORT_SYMBOL(__netif_schedule); 1108 1109void __netif_rx_schedule(struct net_device *dev) 1110{ 1111 unsigned long flags; 1112 1113 local_irq_save(flags); 1114 dev_hold(dev); 1115 list_add_tail(&dev->poll_list, &__get_cpu_var(softnet_data).poll_list); 1116 if (dev->quota < 0) 1117 dev->quota += dev->weight; 1118 else 1119 dev->quota = dev->weight; 1120 __raise_softirq_irqoff(NET_RX_SOFTIRQ); 1121 local_irq_restore(flags); 1122} 1123EXPORT_SYMBOL(__netif_rx_schedule); 1124 1125void dev_kfree_skb_any(struct sk_buff *skb) 1126{ 1127 if (in_irq() || irqs_disabled()) 1128 dev_kfree_skb_irq(skb); 1129 else 1130 dev_kfree_skb(skb); 1131} 1132EXPORT_SYMBOL(dev_kfree_skb_any); 1133 1134 1135/* Hot-plugging. */ 1136void netif_device_detach(struct net_device *dev) 1137{ 1138 if (test_and_clear_bit(__LINK_STATE_PRESENT, &dev->state) && 1139 netif_running(dev)) { 1140 netif_stop_queue(dev); 1141 } 1142} 1143EXPORT_SYMBOL(netif_device_detach); 1144 1145void netif_device_attach(struct net_device *dev) 1146{ 1147 if (!test_and_set_bit(__LINK_STATE_PRESENT, &dev->state) && 1148 netif_running(dev)) { 1149 netif_wake_queue(dev); 1150 __netdev_watchdog_up(dev); 1151 } 1152} 1153EXPORT_SYMBOL(netif_device_attach); 1154 1155 1156/* 1157 * Invalidate hardware checksum when packet is to be mangled, and 1158 * complete checksum manually on outgoing path. 1159 */ 1160int skb_checksum_help(struct sk_buff *skb, int inward) 1161{ 1162 unsigned int csum; 1163 int ret = 0, offset = skb->h.raw - skb->data; 1164 1165 if (inward) { 1166 skb->ip_summed = CHECKSUM_NONE; 1167 goto out; 1168 } 1169 1170 if (skb_cloned(skb)) { 1171 ret = pskb_expand_head(skb, 0, 0, GFP_ATOMIC); 1172 if (ret) 1173 goto out; 1174 } 1175 1176 BUG_ON(offset > (int)skb->len); 1177 csum = skb_checksum(skb, offset, skb->len-offset, 0); 1178 1179 offset = skb->tail - skb->h.raw; 1180 BUG_ON(offset <= 0); 1181 BUG_ON(skb->csum + 2 > offset); 1182 1183 *(u16*)(skb->h.raw + skb->csum) = csum_fold(csum); 1184 skb->ip_summed = CHECKSUM_NONE; 1185out: 1186 return ret; 1187} 1188 1189/** 1190 * skb_gso_segment - Perform segmentation on skb. 1191 * @skb: buffer to segment 1192 * @features: features for the output path (see dev->features) 1193 * 1194 * This function segments the given skb and returns a list of segments. 1195 * 1196 * It may return NULL if the skb requires no segmentation. This is 1197 * only possible when GSO is used for verifying header integrity. 1198 */ 1199struct sk_buff *skb_gso_segment(struct sk_buff *skb, int features) 1200{ 1201 struct sk_buff *segs = ERR_PTR(-EPROTONOSUPPORT); 1202 struct packet_type *ptype; 1203 int type = skb->protocol; 1204 1205 BUG_ON(skb_shinfo(skb)->frag_list); 1206 BUG_ON(skb->ip_summed != CHECKSUM_HW); 1207 1208 skb->mac.raw = skb->data; 1209 skb->mac_len = skb->nh.raw - skb->data; 1210 __skb_pull(skb, skb->mac_len); 1211 1212 rcu_read_lock(); 1213 list_for_each_entry_rcu(ptype, &ptype_base[ntohs(type) & 15], list) { 1214 if (ptype->type == type && !ptype->dev && ptype->gso_segment) { 1215 segs = ptype->gso_segment(skb, features); 1216 break; 1217 } 1218 } 1219 rcu_read_unlock(); 1220 1221 __skb_push(skb, skb->data - skb->mac.raw); 1222 1223 return segs; 1224} 1225 1226EXPORT_SYMBOL(skb_gso_segment); 1227 1228/* Take action when hardware reception checksum errors are detected. */ 1229#ifdef CONFIG_BUG 1230void netdev_rx_csum_fault(struct net_device *dev) 1231{ 1232 if (net_ratelimit()) { 1233 printk(KERN_ERR "%s: hw csum failure.\n", 1234 dev ? dev->name : "<unknown>"); 1235 dump_stack(); 1236 } 1237} 1238EXPORT_SYMBOL(netdev_rx_csum_fault); 1239#endif 1240 1241/* Actually, we should eliminate this check as soon as we know, that: 1242 * 1. IOMMU is present and allows to map all the memory. 1243 * 2. No high memory really exists on this machine. 1244 */ 1245 1246static inline int illegal_highdma(struct net_device *dev, struct sk_buff *skb) 1247{ 1248#ifdef CONFIG_HIGHMEM 1249 int i; 1250 1251 if (dev->features & NETIF_F_HIGHDMA) 1252 return 0; 1253 1254 for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) 1255 if (PageHighMem(skb_shinfo(skb)->frags[i].page)) 1256 return 1; 1257 1258#endif 1259 return 0; 1260} 1261 1262struct dev_gso_cb { 1263 void (*destructor)(struct sk_buff *skb); 1264}; 1265 1266#define DEV_GSO_CB(skb) ((struct dev_gso_cb *)(skb)->cb) 1267 1268static void dev_gso_skb_destructor(struct sk_buff *skb) 1269{ 1270 struct dev_gso_cb *cb; 1271 1272 do { 1273 struct sk_buff *nskb = skb->next; 1274 1275 skb->next = nskb->next; 1276 nskb->next = NULL; 1277 kfree_skb(nskb); 1278 } while (skb->next); 1279 1280 cb = DEV_GSO_CB(skb); 1281 if (cb->destructor) 1282 cb->destructor(skb); 1283} 1284 1285/** 1286 * dev_gso_segment - Perform emulated hardware segmentation on skb. 1287 * @skb: buffer to segment 1288 * 1289 * This function segments the given skb and stores the list of segments 1290 * in skb->next. 1291 */ 1292static int dev_gso_segment(struct sk_buff *skb) 1293{ 1294 struct net_device *dev = skb->dev; 1295 struct sk_buff *segs; 1296 int features = dev->features & ~(illegal_highdma(dev, skb) ? 1297 NETIF_F_SG : 0); 1298 1299 segs = skb_gso_segment(skb, features); 1300 1301 /* Verifying header integrity only. */ 1302 if (!segs) 1303 return 0; 1304 1305 if (unlikely(IS_ERR(segs))) 1306 return PTR_ERR(segs); 1307 1308 skb->next = segs; 1309 DEV_GSO_CB(skb)->destructor = skb->destructor; 1310 skb->destructor = dev_gso_skb_destructor; 1311 1312 return 0; 1313} 1314 1315int dev_hard_start_xmit(struct sk_buff *skb, struct net_device *dev) 1316{ 1317 if (likely(!skb->next)) { 1318 if (netdev_nit) 1319 dev_queue_xmit_nit(skb, dev); 1320 1321 if (netif_needs_gso(dev, skb)) { 1322 if (unlikely(dev_gso_segment(skb))) 1323 goto out_kfree_skb; 1324 if (skb->next) 1325 goto gso; 1326 } 1327 1328 return dev->hard_start_xmit(skb, dev); 1329 } 1330 1331gso: 1332 do { 1333 struct sk_buff *nskb = skb->next; 1334 int rc; 1335 1336 skb->next = nskb->next; 1337 nskb->next = NULL; 1338 rc = dev->hard_start_xmit(nskb, dev); 1339 if (unlikely(rc)) { 1340 nskb->next = skb->next; 1341 skb->next = nskb; 1342 return rc; 1343 } 1344 if (unlikely(netif_queue_stopped(dev) && skb->next)) 1345 return NETDEV_TX_BUSY; 1346 } while (skb->next); 1347 1348 skb->destructor = DEV_GSO_CB(skb)->destructor; 1349 1350out_kfree_skb: 1351 kfree_skb(skb); 1352 return 0; 1353} 1354 1355#define HARD_TX_LOCK(dev, cpu) { \ 1356 if ((dev->features & NETIF_F_LLTX) == 0) { \ 1357 netif_tx_lock(dev); \ 1358 } \ 1359} 1360 1361#define HARD_TX_UNLOCK(dev) { \ 1362 if ((dev->features & NETIF_F_LLTX) == 0) { \ 1363 netif_tx_unlock(dev); \ 1364 } \ 1365} 1366 1367/** 1368 * dev_queue_xmit - transmit a buffer 1369 * @skb: buffer to transmit 1370 * 1371 * Queue a buffer for transmission to a network device. The caller must 1372 * have set the device and priority and built the buffer before calling 1373 * this function. The function can be called from an interrupt. 1374 * 1375 * A negative errno code is returned on a failure. A success does not 1376 * guarantee the frame will be transmitted as it may be dropped due 1377 * to congestion or traffic shaping. 1378 * 1379 * ----------------------------------------------------------------------------------- 1380 * I notice this method can also return errors from the queue disciplines, 1381 * including NET_XMIT_DROP, which is a positive value. So, errors can also 1382 * be positive. 1383 * 1384 * Regardless of the return value, the skb is consumed, so it is currently 1385 * difficult to retry a send to this method. (You can bump the ref count 1386 * before sending to hold a reference for retry if you are careful.) 1387 * 1388 * When calling this method, interrupts MUST be enabled. This is because 1389 * the BH enable code must have IRQs enabled so that it will not deadlock. 1390 * --BLG 1391 */ 1392 1393int dev_queue_xmit(struct sk_buff *skb) 1394{ 1395 struct net_device *dev = skb->dev; 1396 struct Qdisc *q; 1397 int rc = -ENOMEM; 1398 1399 /* GSO will handle the following emulations directly. */ 1400 if (netif_needs_gso(dev, skb)) 1401 goto gso; 1402 1403 if (skb_shinfo(skb)->frag_list && 1404 !(dev->features & NETIF_F_FRAGLIST) && 1405 __skb_linearize(skb)) 1406 goto out_kfree_skb; 1407 1408 /* Fragmented skb is linearized if device does not support SG, 1409 * or if at least one of fragments is in highmem and device 1410 * does not support DMA from it. 1411 */ 1412 if (skb_shinfo(skb)->nr_frags && 1413 (!(dev->features & NETIF_F_SG) || illegal_highdma(dev, skb)) && 1414 __skb_linearize(skb)) 1415 goto out_kfree_skb; 1416 1417 /* If packet is not checksummed and device does not support 1418 * checksumming for this protocol, complete checksumming here. 1419 */ 1420 if (skb->ip_summed == CHECKSUM_HW && 1421 (!(dev->features & NETIF_F_GEN_CSUM) && 1422 (!(dev->features & NETIF_F_IP_CSUM) || 1423 skb->protocol != htons(ETH_P_IP)))) 1424 if (skb_checksum_help(skb, 0)) 1425 goto out_kfree_skb; 1426 1427gso: 1428 spin_lock_prefetch(&dev->queue_lock); 1429 1430 /* Disable soft irqs for various locks below. Also 1431 * stops preemption for RCU. 1432 */ 1433 rcu_read_lock_bh(); 1434 1435 /* Updates of qdisc are serialized by queue_lock. 1436 * The struct Qdisc which is pointed to by qdisc is now a 1437 * rcu structure - it may be accessed without acquiring 1438 * a lock (but the structure may be stale.) The freeing of the 1439 * qdisc will be deferred until it's known that there are no 1440 * more references to it. 1441 * 1442 * If the qdisc has an enqueue function, we still need to 1443 * hold the queue_lock before calling it, since queue_lock 1444 * also serializes access to the device queue. 1445 */ 1446 1447 q = rcu_dereference(dev->qdisc); 1448#ifdef CONFIG_NET_CLS_ACT 1449 skb->tc_verd = SET_TC_AT(skb->tc_verd,AT_EGRESS); 1450#endif 1451 if (q->enqueue) { 1452 /* Grab device queue */ 1453 spin_lock(&dev->queue_lock); 1454 1455 rc = q->enqueue(skb, q); 1456 1457 qdisc_run(dev); 1458 1459 spin_unlock(&dev->queue_lock); 1460 rc = rc == NET_XMIT_BYPASS ? NET_XMIT_SUCCESS : rc; 1461 goto out; 1462 } 1463 1464 /* The device has no queue. Common case for software devices: 1465 loopback, all the sorts of tunnels... 1466 1467 Really, it is unlikely that netif_tx_lock protection is necessary 1468 here. (f.e. loopback and IP tunnels are clean ignoring statistics 1469 counters.) 1470 However, it is possible, that they rely on protection 1471 made by us here. 1472 1473 Check this and shot the lock. It is not prone from deadlocks. 1474 Either shot noqueue qdisc, it is even simpler 8) 1475 */ 1476 if (dev->flags & IFF_UP) { 1477 int cpu = smp_processor_id(); /* ok because BHs are off */ 1478 1479 if (dev->xmit_lock_owner != cpu) { 1480 1481 HARD_TX_LOCK(dev, cpu); 1482 1483 if (!netif_queue_stopped(dev)) { 1484 rc = 0; 1485 if (!dev_hard_start_xmit(skb, dev)) { 1486 HARD_TX_UNLOCK(dev); 1487 goto out; 1488 } 1489 } 1490 HARD_TX_UNLOCK(dev); 1491 if (net_ratelimit()) 1492 printk(KERN_CRIT "Virtual device %s asks to " 1493 "queue packet!\n", dev->name); 1494 } else { 1495 /* Recursion is detected! It is possible, 1496 * unfortunately */ 1497 if (net_ratelimit()) 1498 printk(KERN_CRIT "Dead loop on virtual device " 1499 "%s, fix it urgently!\n", dev->name); 1500 } 1501 } 1502 1503 rc = -ENETDOWN; 1504 rcu_read_unlock_bh(); 1505 1506out_kfree_skb: 1507 kfree_skb(skb); 1508 return rc; 1509out: 1510 rcu_read_unlock_bh(); 1511 return rc; 1512} 1513 1514 1515/*======================================================================= 1516 Receiver routines 1517 =======================================================================*/ 1518 1519int netdev_max_backlog = 1000; 1520int netdev_budget = 300; 1521int weight_p = 64; /* old backlog weight */ 1522 1523DEFINE_PER_CPU(struct netif_rx_stats, netdev_rx_stat) = { 0, }; 1524 1525 1526/** 1527 * netif_rx - post buffer to the network code 1528 * @skb: buffer to post 1529 * 1530 * This function receives a packet from a device driver and queues it for 1531 * the upper (protocol) levels to process. It always succeeds. The buffer 1532 * may be dropped during processing for congestion control or by the 1533 * protocol layers. 1534 * 1535 * return values: 1536 * NET_RX_SUCCESS (no congestion) 1537 * NET_RX_CN_LOW (low congestion) 1538 * NET_RX_CN_MOD (moderate congestion) 1539 * NET_RX_CN_HIGH (high congestion) 1540 * NET_RX_DROP (packet was dropped) 1541 * 1542 */ 1543 1544int netif_rx(struct sk_buff *skb) 1545{ 1546 struct softnet_data *queue; 1547 unsigned long flags; 1548 1549 /* if netpoll wants it, pretend we never saw it */ 1550 if (netpoll_rx(skb)) 1551 return NET_RX_DROP; 1552 1553 if (!skb->tstamp.off_sec) 1554 net_timestamp(skb); 1555 1556 /* 1557 * The code is rearranged so that the path is the most 1558 * short when CPU is congested, but is still operating. 1559 */ 1560 local_irq_save(flags); 1561 queue = &__get_cpu_var(softnet_data); 1562 1563 __get_cpu_var(netdev_rx_stat).total++; 1564 if (queue->input_pkt_queue.qlen <= netdev_max_backlog) { 1565 if (queue->input_pkt_queue.qlen) { 1566enqueue: 1567 dev_hold(skb->dev); 1568 __skb_queue_tail(&queue->input_pkt_queue, skb); 1569 local_irq_restore(flags); 1570 return NET_RX_SUCCESS; 1571 } 1572 1573 netif_rx_schedule(&queue->backlog_dev); 1574 goto enqueue; 1575 } 1576 1577 __get_cpu_var(netdev_rx_stat).dropped++; 1578 local_irq_restore(flags); 1579 1580 kfree_skb(skb); 1581 return NET_RX_DROP; 1582} 1583 1584int netif_rx_ni(struct sk_buff *skb) 1585{ 1586 int err; 1587 1588 preempt_disable(); 1589 err = netif_rx(skb); 1590 if (local_softirq_pending()) 1591 do_softirq(); 1592 preempt_enable(); 1593 1594 return err; 1595} 1596 1597EXPORT_SYMBOL(netif_rx_ni); 1598 1599static inline struct net_device *skb_bond(struct sk_buff *skb) 1600{ 1601 struct net_device *dev = skb->dev; 1602 1603 if (dev->master) { 1604 /* 1605 * On bonding slaves other than the currently active 1606 * slave, suppress duplicates except for 802.3ad 1607 * ETH_P_SLOW and alb non-mcast/bcast. 1608 */ 1609 if (dev->priv_flags & IFF_SLAVE_INACTIVE) { 1610 if (dev->master->priv_flags & IFF_MASTER_ALB) { 1611 if (skb->pkt_type != PACKET_BROADCAST && 1612 skb->pkt_type != PACKET_MULTICAST) 1613 goto keep; 1614 } 1615 1616 if (dev->master->priv_flags & IFF_MASTER_8023AD && 1617 skb->protocol == __constant_htons(ETH_P_SLOW)) 1618 goto keep; 1619 1620 kfree_skb(skb); 1621 return NULL; 1622 } 1623keep: 1624 skb->dev = dev->master; 1625 } 1626 1627 return dev; 1628} 1629 1630static void net_tx_action(struct softirq_action *h) 1631{ 1632 struct softnet_data *sd = &__get_cpu_var(softnet_data); 1633 1634 if (sd->completion_queue) { 1635 struct sk_buff *clist; 1636 1637 local_irq_disable(); 1638 clist = sd->completion_queue; 1639 sd->completion_queue = NULL; 1640 local_irq_enable(); 1641 1642 while (clist) { 1643 struct sk_buff *skb = clist; 1644 clist = clist->next; 1645 1646 BUG_TRAP(!atomic_read(&skb->users)); 1647 __kfree_skb(skb); 1648 } 1649 } 1650 1651 if (sd->output_queue) { 1652 struct net_device *head; 1653 1654 local_irq_disable(); 1655 head = sd->output_queue; 1656 sd->output_queue = NULL; 1657 local_irq_enable(); 1658 1659 while (head) { 1660 struct net_device *dev = head; 1661 head = head->next_sched; 1662 1663 smp_mb__before_clear_bit(); 1664 clear_bit(__LINK_STATE_SCHED, &dev->state); 1665 1666 if (spin_trylock(&dev->queue_lock)) { 1667 qdisc_run(dev); 1668 spin_unlock(&dev->queue_lock); 1669 } else { 1670 netif_schedule(dev); 1671 } 1672 } 1673 } 1674} 1675 1676static __inline__ int deliver_skb(struct sk_buff *skb, 1677 struct packet_type *pt_prev, 1678 struct net_device *orig_dev) 1679{ 1680 atomic_inc(&skb->users); 1681 return pt_prev->func(skb, skb->dev, pt_prev, orig_dev); 1682} 1683 1684#if defined(CONFIG_BRIDGE) || defined (CONFIG_BRIDGE_MODULE) 1685int (*br_handle_frame_hook)(struct net_bridge_port *p, struct sk_buff **pskb); 1686struct net_bridge; 1687struct net_bridge_fdb_entry *(*br_fdb_get_hook)(struct net_bridge *br, 1688 unsigned char *addr); 1689void (*br_fdb_put_hook)(struct net_bridge_fdb_entry *ent); 1690 1691static __inline__ int handle_bridge(struct sk_buff **pskb, 1692 struct packet_type **pt_prev, int *ret, 1693 struct net_device *orig_dev) 1694{ 1695 struct net_bridge_port *port; 1696 1697 if ((*pskb)->pkt_type == PACKET_LOOPBACK || 1698 (port = rcu_dereference((*pskb)->dev->br_port)) == NULL) 1699 return 0; 1700 1701 if (*pt_prev) { 1702 *ret = deliver_skb(*pskb, *pt_prev, orig_dev); 1703 *pt_prev = NULL; 1704 } 1705 1706 return br_handle_frame_hook(port, pskb); 1707} 1708#else 1709#define handle_bridge(skb, pt_prev, ret, orig_dev) (0) 1710#endif 1711 1712#ifdef CONFIG_NET_CLS_ACT 1713/* TODO: Maybe we should just force sch_ingress to be compiled in 1714 * when CONFIG_NET_CLS_ACT is? otherwise some useless instructions 1715 * a compare and 2 stores extra right now if we dont have it on 1716 * but have CONFIG_NET_CLS_ACT 1717 * NOTE: This doesnt stop any functionality; if you dont have 1718 * the ingress scheduler, you just cant add policies on ingress. 1719 * 1720 */ 1721static int ing_filter(struct sk_buff *skb) 1722{ 1723 struct Qdisc *q; 1724 struct net_device *dev = skb->dev; 1725 int result = TC_ACT_OK; 1726 1727 if (dev->qdisc_ingress) { 1728 __u32 ttl = (__u32) G_TC_RTTL(skb->tc_verd); 1729 if (MAX_RED_LOOP < ttl++) { 1730 printk("Redir loop detected Dropping packet (%s->%s)\n", 1731 skb->input_dev->name, skb->dev->name); 1732 return TC_ACT_SHOT; 1733 } 1734 1735 skb->tc_verd = SET_TC_RTTL(skb->tc_verd,ttl); 1736 1737 skb->tc_verd = SET_TC_AT(skb->tc_verd,AT_INGRESS); 1738 1739 spin_lock(&dev->ingress_lock); 1740 if ((q = dev->qdisc_ingress) != NULL) 1741 result = q->enqueue(skb, q); 1742 spin_unlock(&dev->ingress_lock); 1743 1744 } 1745 1746 return result; 1747} 1748#endif 1749 1750int netif_receive_skb(struct sk_buff *skb) 1751{ 1752 struct packet_type *ptype, *pt_prev; 1753 struct net_device *orig_dev; 1754 int ret = NET_RX_DROP; 1755 unsigned short type; 1756 1757 /* if we've gotten here through NAPI, check netpoll */ 1758 if (skb->dev->poll && netpoll_rx(skb)) 1759 return NET_RX_DROP; 1760 1761 if (!skb->tstamp.off_sec) 1762 net_timestamp(skb); 1763 1764 if (!skb->input_dev) 1765 skb->input_dev = skb->dev; 1766 1767 orig_dev = skb_bond(skb); 1768 1769 if (!orig_dev) 1770 return NET_RX_DROP; 1771 1772 __get_cpu_var(netdev_rx_stat).total++; 1773 1774 skb->h.raw = skb->nh.raw = skb->data; 1775 skb->mac_len = skb->nh.raw - skb->mac.raw; 1776 1777 pt_prev = NULL; 1778 1779 rcu_read_lock(); 1780 1781#ifdef CONFIG_NET_CLS_ACT 1782 if (skb->tc_verd & TC_NCLS) { 1783 skb->tc_verd = CLR_TC_NCLS(skb->tc_verd); 1784 goto ncls; 1785 } 1786#endif 1787 1788 list_for_each_entry_rcu(ptype, &ptype_all, list) { 1789 if (!ptype->dev || ptype->dev == skb->dev) { 1790 if (pt_prev) 1791 ret = deliver_skb(skb, pt_prev, orig_dev); 1792 pt_prev = ptype; 1793 } 1794 } 1795 1796#ifdef CONFIG_NET_CLS_ACT 1797 if (pt_prev) { 1798 ret = deliver_skb(skb, pt_prev, orig_dev); 1799 pt_prev = NULL; /* noone else should process this after*/ 1800 } else { 1801 skb->tc_verd = SET_TC_OK2MUNGE(skb->tc_verd); 1802 } 1803 1804 ret = ing_filter(skb); 1805 1806 if (ret == TC_ACT_SHOT || (ret == TC_ACT_STOLEN)) { 1807 kfree_skb(skb); 1808 goto out; 1809 } 1810 1811 skb->tc_verd = 0; 1812ncls: 1813#endif 1814 1815 handle_diverter(skb); 1816 1817 if (handle_bridge(&skb, &pt_prev, &ret, orig_dev)) 1818 goto out; 1819 1820 type = skb->protocol; 1821 list_for_each_entry_rcu(ptype, &ptype_base[ntohs(type)&15], list) { 1822 if (ptype->type == type && 1823 (!ptype->dev || ptype->dev == skb->dev)) { 1824 if (pt_prev) 1825 ret = deliver_skb(skb, pt_prev, orig_dev); 1826 pt_prev = ptype; 1827 } 1828 } 1829 1830 if (pt_prev) { 1831 ret = pt_prev->func(skb, skb->dev, pt_prev, orig_dev); 1832 } else { 1833 kfree_skb(skb); 1834 /* Jamal, now you will not able to escape explaining 1835 * me how you were going to use this. :-) 1836 */ 1837 ret = NET_RX_DROP; 1838 } 1839 1840out: 1841 rcu_read_unlock(); 1842 return ret; 1843} 1844 1845static int process_backlog(struct net_device *backlog_dev, int *budget) 1846{ 1847 int work = 0; 1848 int quota = min(backlog_dev->quota, *budget); 1849 struct softnet_data *queue = &__get_cpu_var(softnet_data); 1850 unsigned long start_time = jiffies; 1851 1852 backlog_dev->weight = weight_p; 1853 for (;;) { 1854 struct sk_buff *skb; 1855 struct net_device *dev; 1856 1857 local_irq_disable(); 1858 skb = __skb_dequeue(&queue->input_pkt_queue); 1859 if (!skb) 1860 goto job_done; 1861 local_irq_enable(); 1862 1863 dev = skb->dev; 1864 1865 netif_receive_skb(skb); 1866 1867 dev_put(dev); 1868 1869 work++; 1870 1871 if (work >= quota || jiffies - start_time > 1) 1872 break; 1873 1874 } 1875 1876 backlog_dev->quota -= work; 1877 *budget -= work; 1878 return -1; 1879 1880job_done: 1881 backlog_dev->quota -= work; 1882 *budget -= work; 1883 1884 list_del(&backlog_dev->poll_list); 1885 smp_mb__before_clear_bit(); 1886 netif_poll_enable(backlog_dev); 1887 1888 local_irq_enable(); 1889 return 0; 1890} 1891 1892static void net_rx_action(struct softirq_action *h) 1893{ 1894 struct softnet_data *queue = &__get_cpu_var(softnet_data); 1895 unsigned long start_time = jiffies; 1896 int budget = netdev_budget; 1897 void *have; 1898 1899 local_irq_disable(); 1900 1901 while (!list_empty(&queue->poll_list)) { 1902 struct net_device *dev; 1903 1904 if (budget <= 0 || jiffies - start_time > 1) 1905 goto softnet_break; 1906 1907 local_irq_enable(); 1908 1909 dev = list_entry(queue->poll_list.next, 1910 struct net_device, poll_list); 1911 have = netpoll_poll_lock(dev); 1912 1913 if (dev->quota <= 0 || dev->poll(dev, &budget)) { 1914 netpoll_poll_unlock(have); 1915 local_irq_disable(); 1916 list_move_tail(&dev->poll_list, &queue->poll_list); 1917 if (dev->quota < 0) 1918 dev->quota += dev->weight; 1919 else 1920 dev->quota = dev->weight; 1921 } else { 1922 netpoll_poll_unlock(have); 1923 dev_put(dev); 1924 local_irq_disable(); 1925 } 1926 } 1927out: 1928#ifdef CONFIG_NET_DMA 1929 /* 1930 * There may not be any more sk_buffs coming right now, so push 1931 * any pending DMA copies to hardware 1932 */ 1933 if (net_dma_client) { 1934 struct dma_chan *chan; 1935 rcu_read_lock(); 1936 list_for_each_entry_rcu(chan, &net_dma_client->channels, client_node) 1937 dma_async_memcpy_issue_pending(chan); 1938 rcu_read_unlock(); 1939 } 1940#endif 1941 local_irq_enable(); 1942 return; 1943 1944softnet_break: 1945 __get_cpu_var(netdev_rx_stat).time_squeeze++; 1946 __raise_softirq_irqoff(NET_RX_SOFTIRQ); 1947 goto out; 1948} 1949 1950static gifconf_func_t * gifconf_list [NPROTO]; 1951 1952/** 1953 * register_gifconf - register a SIOCGIF handler 1954 * @family: Address family 1955 * @gifconf: Function handler 1956 * 1957 * Register protocol dependent address dumping routines. The handler 1958 * that is passed must not be freed or reused until it has been replaced 1959 * by another handler. 1960 */ 1961int register_gifconf(unsigned int family, gifconf_func_t * gifconf) 1962{ 1963 if (family >= NPROTO) 1964 return -EINVAL; 1965 gifconf_list[family] = gifconf; 1966 return 0; 1967} 1968 1969 1970/* 1971 * Map an interface index to its name (SIOCGIFNAME) 1972 */ 1973 1974/* 1975 * We need this ioctl for efficient implementation of the 1976 * if_indextoname() function required by the IPv6 API. Without 1977 * it, we would have to search all the interfaces to find a 1978 * match. --pb 1979 */ 1980 1981static int dev_ifname(struct ifreq __user *arg) 1982{ 1983 struct net_device *dev; 1984 struct ifreq ifr; 1985 1986 /* 1987 * Fetch the caller's info block. 1988 */ 1989 1990 if (copy_from_user(&ifr, arg, sizeof(struct ifreq))) 1991 return -EFAULT; 1992 1993 read_lock(&dev_base_lock); 1994 dev = __dev_get_by_index(ifr.ifr_ifindex); 1995 if (!dev) { 1996 read_unlock(&dev_base_lock); 1997 return -ENODEV; 1998 } 1999 2000 strcpy(ifr.ifr_name, dev->name); 2001 read_unlock(&dev_base_lock); 2002 2003 if (copy_to_user(arg, &ifr, sizeof(struct ifreq))) 2004 return -EFAULT; 2005 return 0; 2006} 2007 2008/* 2009 * Perform a SIOCGIFCONF call. This structure will change 2010 * size eventually, and there is nothing I can do about it. 2011 * Thus we will need a 'compatibility mode'. 2012 */ 2013 2014static int dev_ifconf(char __user *arg) 2015{ 2016 struct ifconf ifc; 2017 struct net_device *dev; 2018 char __user *pos; 2019 int len; 2020 int total; 2021 int i; 2022 2023 /* 2024 * Fetch the caller's info block. 2025 */ 2026 2027 if (copy_from_user(&ifc, arg, sizeof(struct ifconf))) 2028 return -EFAULT; 2029 2030 pos = ifc.ifc_buf; 2031 len = ifc.ifc_len; 2032 2033 /* 2034 * Loop over the interfaces, and write an info block for each. 2035 */ 2036 2037 total = 0; 2038 for (dev = dev_base; dev; dev = dev->next) { 2039 for (i = 0; i < NPROTO; i++) { 2040 if (gifconf_list[i]) { 2041 int done; 2042 if (!pos) 2043 done = gifconf_list[i](dev, NULL, 0); 2044 else 2045 done = gifconf_list[i](dev, pos + total, 2046 len - total); 2047 if (done < 0) 2048 return -EFAULT; 2049 total += done; 2050 } 2051 } 2052 } 2053 2054 /* 2055 * All done. Write the updated control block back to the caller. 2056 */ 2057 ifc.ifc_len = total; 2058 2059 /* 2060 * Both BSD and Solaris return 0 here, so we do too. 2061 */ 2062 return copy_to_user(arg, &ifc, sizeof(struct ifconf)) ? -EFAULT : 0; 2063} 2064 2065#ifdef CONFIG_PROC_FS 2066/* 2067 * This is invoked by the /proc filesystem handler to display a device 2068 * in detail. 2069 */ 2070static __inline__ struct net_device *dev_get_idx(loff_t pos) 2071{ 2072 struct net_device *dev; 2073 loff_t i; 2074 2075 for (i = 0, dev = dev_base; dev && i < pos; ++i, dev = dev->next); 2076 2077 return i == pos ? dev : NULL; 2078} 2079 2080void *dev_seq_start(struct seq_file *seq, loff_t *pos) 2081{ 2082 read_lock(&dev_base_lock); 2083 return *pos ? dev_get_idx(*pos - 1) : SEQ_START_TOKEN; 2084} 2085 2086void *dev_seq_next(struct seq_file *seq, void *v, loff_t *pos) 2087{ 2088 ++*pos; 2089 return v == SEQ_START_TOKEN ? dev_base : ((struct net_device *)v)->next; 2090} 2091 2092void dev_seq_stop(struct seq_file *seq, void *v) 2093{ 2094 read_unlock(&dev_base_lock); 2095} 2096 2097static void dev_seq_printf_stats(struct seq_file *seq, struct net_device *dev) 2098{ 2099 if (dev->get_stats) { 2100 struct net_device_stats *stats = dev->get_stats(dev); 2101 2102 seq_printf(seq, "%6s:%8lu %7lu %4lu %4lu %4lu %5lu %10lu %9lu " 2103 "%8lu %7lu %4lu %4lu %4lu %5lu %7lu %10lu\n", 2104 dev->name, stats->rx_bytes, stats->rx_packets, 2105 stats->rx_errors, 2106 stats->rx_dropped + stats->rx_missed_errors, 2107 stats->rx_fifo_errors, 2108 stats->rx_length_errors + stats->rx_over_errors + 2109 stats->rx_crc_errors + stats->rx_frame_errors, 2110 stats->rx_compressed, stats->multicast, 2111 stats->tx_bytes, stats->tx_packets, 2112 stats->tx_errors, stats->tx_dropped, 2113 stats->tx_fifo_errors, stats->collisions, 2114 stats->tx_carrier_errors + 2115 stats->tx_aborted_errors + 2116 stats->tx_window_errors + 2117 stats->tx_heartbeat_errors, 2118 stats->tx_compressed); 2119 } else 2120 seq_printf(seq, "%6s: No statistics available.\n", dev->name); 2121} 2122 2123/* 2124 * Called from the PROCfs module. This now uses the new arbitrary sized 2125 * /proc/net interface to create /proc/net/dev 2126 */ 2127static int dev_seq_show(struct seq_file *seq, void *v) 2128{ 2129 if (v == SEQ_START_TOKEN) 2130 seq_puts(seq, "Inter-| Receive " 2131 " | Transmit\n" 2132 " face |bytes packets errs drop fifo frame " 2133 "compressed multicast|bytes packets errs " 2134 "drop fifo colls carrier compressed\n"); 2135 else 2136 dev_seq_printf_stats(seq, v); 2137 return 0; 2138} 2139 2140static struct netif_rx_stats *softnet_get_online(loff_t *pos) 2141{ 2142 struct netif_rx_stats *rc = NULL; 2143 2144 while (*pos < NR_CPUS) 2145 if (cpu_online(*pos)) { 2146 rc = &per_cpu(netdev_rx_stat, *pos); 2147 break; 2148 } else 2149 ++*pos; 2150 return rc; 2151} 2152 2153static void *softnet_seq_start(struct seq_file *seq, loff_t *pos) 2154{ 2155 return softnet_get_online(pos); 2156} 2157 2158static void *softnet_seq_next(struct seq_file *seq, void *v, loff_t *pos) 2159{ 2160 ++*pos; 2161 return softnet_get_online(pos); 2162} 2163 2164static void softnet_seq_stop(struct seq_file *seq, void *v) 2165{ 2166} 2167 2168static int softnet_seq_show(struct seq_file *seq, void *v) 2169{ 2170 struct netif_rx_stats *s = v; 2171 2172 seq_printf(seq, "%08x %08x %08x %08x %08x %08x %08x %08x %08x\n", 2173 s->total, s->dropped, s->time_squeeze, 0, 2174 0, 0, 0, 0, /* was fastroute */ 2175 s->cpu_collision ); 2176 return 0; 2177} 2178 2179static struct seq_operations dev_seq_ops = { 2180 .start = dev_seq_start, 2181 .next = dev_seq_next, 2182 .stop = dev_seq_stop, 2183 .show = dev_seq_show, 2184}; 2185 2186static int dev_seq_open(struct inode *inode, struct file *file) 2187{ 2188 return seq_open(file, &dev_seq_ops); 2189} 2190 2191static struct file_operations dev_seq_fops = { 2192 .owner = THIS_MODULE, 2193 .open = dev_seq_open, 2194 .read = seq_read, 2195 .llseek = seq_lseek, 2196 .release = seq_release, 2197}; 2198 2199static struct seq_operations softnet_seq_ops = { 2200 .start = softnet_seq_start, 2201 .next = softnet_seq_next, 2202 .stop = softnet_seq_stop, 2203 .show = softnet_seq_show, 2204}; 2205 2206static int softnet_seq_open(struct inode *inode, struct file *file) 2207{ 2208 return seq_open(file, &softnet_seq_ops); 2209} 2210 2211static struct file_operations softnet_seq_fops = { 2212 .owner = THIS_MODULE, 2213 .open = softnet_seq_open, 2214 .read = seq_read, 2215 .llseek = seq_lseek, 2216 .release = seq_release, 2217}; 2218 2219#ifdef CONFIG_WIRELESS_EXT 2220extern int wireless_proc_init(void); 2221#else 2222#define wireless_proc_init() 0 2223#endif 2224 2225static int __init dev_proc_init(void) 2226{ 2227 int rc = -ENOMEM; 2228 2229 if (!proc_net_fops_create("dev", S_IRUGO, &dev_seq_fops)) 2230 goto out; 2231 if (!proc_net_fops_create("softnet_stat", S_IRUGO, &softnet_seq_fops)) 2232 goto out_dev; 2233 if (wireless_proc_init()) 2234 goto out_softnet; 2235 rc = 0; 2236out: 2237 return rc; 2238out_softnet: 2239 proc_net_remove("softnet_stat"); 2240out_dev: 2241 proc_net_remove("dev"); 2242 goto out; 2243} 2244#else 2245#define dev_proc_init() 0 2246#endif /* CONFIG_PROC_FS */ 2247 2248 2249/** 2250 * netdev_set_master - set up master/slave pair 2251 * @slave: slave device 2252 * @master: new master device 2253 * 2254 * Changes the master device of the slave. Pass %NULL to break the 2255 * bonding. The caller must hold the RTNL semaphore. On a failure 2256 * a negative errno code is returned. On success the reference counts 2257 * are adjusted, %RTM_NEWLINK is sent to the routing socket and the 2258 * function returns zero. 2259 */ 2260int netdev_set_master(struct net_device *slave, struct net_device *master) 2261{ 2262 struct net_device *old = slave->master; 2263 2264 ASSERT_RTNL(); 2265 2266 if (master) { 2267 if (old) 2268 return -EBUSY; 2269 dev_hold(master); 2270 } 2271 2272 slave->master = master; 2273 2274 synchronize_net(); 2275 2276 if (old) 2277 dev_put(old); 2278 2279 if (master) 2280 slave->flags |= IFF_SLAVE; 2281 else 2282 slave->flags &= ~IFF_SLAVE; 2283 2284 rtmsg_ifinfo(RTM_NEWLINK, slave, IFF_SLAVE); 2285 return 0; 2286} 2287 2288/** 2289 * dev_set_promiscuity - update promiscuity count on a device 2290 * @dev: device 2291 * @inc: modifier 2292 * 2293 * Add or remove promiscuity from a device. While the count in the device 2294 * remains above zero the interface remains promiscuous. Once it hits zero 2295 * the device reverts back to normal filtering operation. A negative inc 2296 * value is used to drop promiscuity on the device. 2297 */ 2298void dev_set_promiscuity(struct net_device *dev, int inc) 2299{ 2300 unsigned short old_flags = dev->flags; 2301 2302 if ((dev->promiscuity += inc) == 0) 2303 dev->flags &= ~IFF_PROMISC; 2304 else 2305 dev->flags |= IFF_PROMISC; 2306 if (dev->flags != old_flags) { 2307 dev_mc_upload(dev); 2308 printk(KERN_INFO "device %s %s promiscuous mode\n", 2309 dev->name, (dev->flags & IFF_PROMISC) ? "entered" : 2310 "left"); 2311 audit_log(current->audit_context, GFP_ATOMIC, 2312 AUDIT_ANOM_PROMISCUOUS, 2313 "dev=%s prom=%d old_prom=%d auid=%u", 2314 dev->name, (dev->flags & IFF_PROMISC), 2315 (old_flags & IFF_PROMISC), 2316 audit_get_loginuid(current->audit_context)); 2317 } 2318} 2319 2320/** 2321 * dev_set_allmulti - update allmulti count on a device 2322 * @dev: device 2323 * @inc: modifier 2324 * 2325 * Add or remove reception of all multicast frames to a device. While the 2326 * count in the device remains above zero the interface remains listening 2327 * to all interfaces. Once it hits zero the device reverts back to normal 2328 * filtering operation. A negative @inc value is used to drop the counter 2329 * when releasing a resource needing all multicasts. 2330 */ 2331 2332void dev_set_allmulti(struct net_device *dev, int inc) 2333{ 2334 unsigned short old_flags = dev->flags; 2335 2336 dev->flags |= IFF_ALLMULTI; 2337 if ((dev->allmulti += inc) == 0) 2338 dev->flags &= ~IFF_ALLMULTI; 2339 if (dev->flags ^ old_flags) 2340 dev_mc_upload(dev); 2341} 2342 2343unsigned dev_get_flags(const struct net_device *dev) 2344{ 2345 unsigned flags; 2346 2347 flags = (dev->flags & ~(IFF_PROMISC | 2348 IFF_ALLMULTI | 2349 IFF_RUNNING | 2350 IFF_LOWER_UP | 2351 IFF_DORMANT)) | 2352 (dev->gflags & (IFF_PROMISC | 2353 IFF_ALLMULTI)); 2354 2355 if (netif_running(dev)) { 2356 if (netif_oper_up(dev)) 2357 flags |= IFF_RUNNING; 2358 if (netif_carrier_ok(dev)) 2359 flags |= IFF_LOWER_UP; 2360 if (netif_dormant(dev)) 2361 flags |= IFF_DORMANT; 2362 } 2363 2364 return flags; 2365} 2366 2367int dev_change_flags(struct net_device *dev, unsigned flags) 2368{ 2369 int ret; 2370 int old_flags = dev->flags; 2371 2372 /* 2373 * Set the flags on our device. 2374 */ 2375 2376 dev->flags = (flags & (IFF_DEBUG | IFF_NOTRAILERS | IFF_NOARP | 2377 IFF_DYNAMIC | IFF_MULTICAST | IFF_PORTSEL | 2378 IFF_AUTOMEDIA)) | 2379 (dev->flags & (IFF_UP | IFF_VOLATILE | IFF_PROMISC | 2380 IFF_ALLMULTI)); 2381 2382 /* 2383 * Load in the correct multicast list now the flags have changed. 2384 */ 2385 2386 dev_mc_upload(dev); 2387 2388 /* 2389 * Have we downed the interface. We handle IFF_UP ourselves 2390 * according to user attempts to set it, rather than blindly 2391 * setting it. 2392 */ 2393 2394 ret = 0; 2395 if ((old_flags ^ flags) & IFF_UP) { /* Bit is different ? */ 2396 ret = ((old_flags & IFF_UP) ? dev_close : dev_open)(dev); 2397 2398 if (!ret) 2399 dev_mc_upload(dev); 2400 } 2401 2402 if (dev->flags & IFF_UP && 2403 ((old_flags ^ dev->flags) &~ (IFF_UP | IFF_PROMISC | IFF_ALLMULTI | 2404 IFF_VOLATILE))) 2405 raw_notifier_call_chain(&netdev_chain, 2406 NETDEV_CHANGE, dev); 2407 2408 if ((flags ^ dev->gflags) & IFF_PROMISC) { 2409 int inc = (flags & IFF_PROMISC) ? +1 : -1; 2410 dev->gflags ^= IFF_PROMISC; 2411 dev_set_promiscuity(dev, inc); 2412 } 2413 2414 /* NOTE: order of synchronization of IFF_PROMISC and IFF_ALLMULTI 2415 is important. Some (broken) drivers set IFF_PROMISC, when 2416 IFF_ALLMULTI is requested not asking us and not reporting. 2417 */ 2418 if ((flags ^ dev->gflags) & IFF_ALLMULTI) { 2419 int inc = (flags & IFF_ALLMULTI) ? +1 : -1; 2420 dev->gflags ^= IFF_ALLMULTI; 2421 dev_set_allmulti(dev, inc); 2422 } 2423 2424 if (old_flags ^ dev->flags) 2425 rtmsg_ifinfo(RTM_NEWLINK, dev, old_flags ^ dev->flags); 2426 2427 return ret; 2428} 2429 2430int dev_set_mtu(struct net_device *dev, int new_mtu) 2431{ 2432 int err; 2433 2434 if (new_mtu == dev->mtu) 2435 return 0; 2436 2437 /* MTU must be positive. */ 2438 if (new_mtu < 0) 2439 return -EINVAL; 2440 2441 if (!netif_device_present(dev)) 2442 return -ENODEV; 2443 2444 err = 0; 2445 if (dev->change_mtu) 2446 err = dev->change_mtu(dev, new_mtu); 2447 else 2448 dev->mtu = new_mtu; 2449 if (!err && dev->flags & IFF_UP) 2450 raw_notifier_call_chain(&netdev_chain, 2451 NETDEV_CHANGEMTU, dev); 2452 return err; 2453} 2454 2455int dev_set_mac_address(struct net_device *dev, struct sockaddr *sa) 2456{ 2457 int err; 2458 2459 if (!dev->set_mac_address) 2460 return -EOPNOTSUPP; 2461 if (sa->sa_family != dev->type) 2462 return -EINVAL; 2463 if (!netif_device_present(dev)) 2464 return -ENODEV; 2465 err = dev->set_mac_address(dev, sa); 2466 if (!err) 2467 raw_notifier_call_chain(&netdev_chain, 2468 NETDEV_CHANGEADDR, dev); 2469 return err; 2470} 2471 2472/* 2473 * Perform the SIOCxIFxxx calls. 2474 */ 2475static int dev_ifsioc(struct ifreq *ifr, unsigned int cmd) 2476{ 2477 int err; 2478 struct net_device *dev = __dev_get_by_name(ifr->ifr_name); 2479 2480 if (!dev) 2481 return -ENODEV; 2482 2483 switch (cmd) { 2484 case SIOCGIFFLAGS: /* Get interface flags */ 2485 ifr->ifr_flags = dev_get_flags(dev); 2486 return 0; 2487 2488 case SIOCSIFFLAGS: /* Set interface flags */ 2489 return dev_change_flags(dev, ifr->ifr_flags); 2490 2491 case SIOCGIFMETRIC: /* Get the metric on the interface 2492 (currently unused) */ 2493 ifr->ifr_metric = 0; 2494 return 0; 2495 2496 case SIOCSIFMETRIC: /* Set the metric on the interface 2497 (currently unused) */ 2498 return -EOPNOTSUPP; 2499 2500 case SIOCGIFMTU: /* Get the MTU of a device */ 2501 ifr->ifr_mtu = dev->mtu; 2502 return 0; 2503 2504 case SIOCSIFMTU: /* Set the MTU of a device */ 2505 return dev_set_mtu(dev, ifr->ifr_mtu); 2506 2507 case SIOCGIFHWADDR: 2508 if (!dev->addr_len) 2509 memset(ifr->ifr_hwaddr.sa_data, 0, sizeof ifr->ifr_hwaddr.sa_data); 2510 else 2511 memcpy(ifr->ifr_hwaddr.sa_data, dev->dev_addr, 2512 min(sizeof ifr->ifr_hwaddr.sa_data, (size_t) dev->addr_len)); 2513 ifr->ifr_hwaddr.sa_family = dev->type; 2514 return 0; 2515 2516 case SIOCSIFHWADDR: 2517 return dev_set_mac_address(dev, &ifr->ifr_hwaddr); 2518 2519 case SIOCSIFHWBROADCAST: 2520 if (ifr->ifr_hwaddr.sa_family != dev->type) 2521 return -EINVAL; 2522 memcpy(dev->broadcast, ifr->ifr_hwaddr.sa_data, 2523 min(sizeof ifr->ifr_hwaddr.sa_data, (size_t) dev->addr_len)); 2524 raw_notifier_call_chain(&netdev_chain, 2525 NETDEV_CHANGEADDR, dev); 2526 return 0; 2527 2528 case SIOCGIFMAP: 2529 ifr->ifr_map.mem_start = dev->mem_start; 2530 ifr->ifr_map.mem_end = dev->mem_end; 2531 ifr->ifr_map.base_addr = dev->base_addr; 2532 ifr->ifr_map.irq = dev->irq; 2533 ifr->ifr_map.dma = dev->dma; 2534 ifr->ifr_map.port = dev->if_port; 2535 return 0; 2536 2537 case SIOCSIFMAP: 2538 if (dev->set_config) { 2539 if (!netif_device_present(dev)) 2540 return -ENODEV; 2541 return dev->set_config(dev, &ifr->ifr_map); 2542 } 2543 return -EOPNOTSUPP; 2544 2545 case SIOCADDMULTI: 2546 if (!dev->set_multicast_list || 2547 ifr->ifr_hwaddr.sa_family != AF_UNSPEC) 2548 return -EINVAL; 2549 if (!netif_device_present(dev)) 2550 return -ENODEV; 2551 return dev_mc_add(dev, ifr->ifr_hwaddr.sa_data, 2552 dev->addr_len, 1); 2553 2554 case SIOCDELMULTI: 2555 if (!dev->set_multicast_list || 2556 ifr->ifr_hwaddr.sa_family != AF_UNSPEC) 2557 return -EINVAL; 2558 if (!netif_device_present(dev)) 2559 return -ENODEV; 2560 return dev_mc_delete(dev, ifr->ifr_hwaddr.sa_data, 2561 dev->addr_len, 1); 2562 2563 case SIOCGIFINDEX: 2564 ifr->ifr_ifindex = dev->ifindex; 2565 return 0; 2566 2567 case SIOCGIFTXQLEN: 2568 ifr->ifr_qlen = dev->tx_queue_len; 2569 return 0; 2570 2571 case SIOCSIFTXQLEN: 2572 if (ifr->ifr_qlen < 0) 2573 return -EINVAL; 2574 dev->tx_queue_len = ifr->ifr_qlen; 2575 return 0; 2576 2577 case SIOCSIFNAME: 2578 ifr->ifr_newname[IFNAMSIZ-1] = '\0'; 2579 return dev_change_name(dev, ifr->ifr_newname); 2580 2581 /* 2582 * Unknown or private ioctl 2583 */ 2584 2585 default: 2586 if ((cmd >= SIOCDEVPRIVATE && 2587 cmd <= SIOCDEVPRIVATE + 15) || 2588 cmd == SIOCBONDENSLAVE || 2589 cmd == SIOCBONDRELEASE || 2590 cmd == SIOCBONDSETHWADDR || 2591 cmd == SIOCBONDSLAVEINFOQUERY || 2592 cmd == SIOCBONDINFOQUERY || 2593 cmd == SIOCBONDCHANGEACTIVE || 2594 cmd == SIOCGMIIPHY || 2595 cmd == SIOCGMIIREG || 2596 cmd == SIOCSMIIREG || 2597 cmd == SIOCBRADDIF || 2598 cmd == SIOCBRDELIF || 2599 cmd == SIOCWANDEV) { 2600 err = -EOPNOTSUPP; 2601 if (dev->do_ioctl) { 2602 if (netif_device_present(dev)) 2603 err = dev->do_ioctl(dev, ifr, 2604 cmd); 2605 else 2606 err = -ENODEV; 2607 } 2608 } else 2609 err = -EINVAL; 2610 2611 } 2612 return err; 2613} 2614 2615/* 2616 * This function handles all "interface"-type I/O control requests. The actual 2617 * 'doing' part of this is dev_ifsioc above. 2618 */ 2619 2620/** 2621 * dev_ioctl - network device ioctl 2622 * @cmd: command to issue 2623 * @arg: pointer to a struct ifreq in user space 2624 * 2625 * Issue ioctl functions to devices. This is normally called by the 2626 * user space syscall interfaces but can sometimes be useful for 2627 * other purposes. The return value is the return from the syscall if 2628 * positive or a negative errno code on error. 2629 */ 2630 2631int dev_ioctl(unsigned int cmd, void __user *arg) 2632{ 2633 struct ifreq ifr; 2634 int ret; 2635 char *colon; 2636 2637 /* One special case: SIOCGIFCONF takes ifconf argument 2638 and requires shared lock, because it sleeps writing 2639 to user space. 2640 */ 2641 2642 if (cmd == SIOCGIFCONF) { 2643 rtnl_lock(); 2644 ret = dev_ifconf((char __user *) arg); 2645 rtnl_unlock(); 2646 return ret; 2647 } 2648 if (cmd == SIOCGIFNAME) 2649 return dev_ifname((struct ifreq __user *)arg); 2650 2651 if (copy_from_user(&ifr, arg, sizeof(struct ifreq))) 2652 return -EFAULT; 2653 2654 ifr.ifr_name[IFNAMSIZ-1] = 0; 2655 2656 colon = strchr(ifr.ifr_name, ':'); 2657 if (colon) 2658 *colon = 0; 2659 2660 /* 2661 * See which interface the caller is talking about. 2662 */ 2663 2664 switch (cmd) { 2665 /* 2666 * These ioctl calls: 2667 * - can be done by all. 2668 * - atomic and do not require locking. 2669 * - return a value 2670 */ 2671 case SIOCGIFFLAGS: 2672 case SIOCGIFMETRIC: 2673 case SIOCGIFMTU: 2674 case SIOCGIFHWADDR: 2675 case SIOCGIFSLAVE: 2676 case SIOCGIFMAP: 2677 case SIOCGIFINDEX: 2678 case SIOCGIFTXQLEN: 2679 dev_load(ifr.ifr_name); 2680 read_lock(&dev_base_lock); 2681 ret = dev_ifsioc(&ifr, cmd); 2682 read_unlock(&dev_base_lock); 2683 if (!ret) { 2684 if (colon) 2685 *colon = ':'; 2686 if (copy_to_user(arg, &ifr, 2687 sizeof(struct ifreq))) 2688 ret = -EFAULT; 2689 } 2690 return ret; 2691 2692 case SIOCETHTOOL: 2693 dev_load(ifr.ifr_name); 2694 rtnl_lock(); 2695 ret = dev_ethtool(&ifr); 2696 rtnl_unlock(); 2697 if (!ret) { 2698 if (colon) 2699 *colon = ':'; 2700 if (copy_to_user(arg, &ifr, 2701 sizeof(struct ifreq))) 2702 ret = -EFAULT; 2703 } 2704 return ret; 2705 2706 /* 2707 * These ioctl calls: 2708 * - require superuser power. 2709 * - require strict serialization. 2710 * - return a value 2711 */ 2712 case SIOCGMIIPHY: 2713 case SIOCGMIIREG: 2714 case SIOCSIFNAME: 2715 if (!capable(CAP_NET_ADMIN)) 2716 return -EPERM; 2717 dev_load(ifr.ifr_name); 2718 rtnl_lock(); 2719 ret = dev_ifsioc(&ifr, cmd); 2720 rtnl_unlock(); 2721 if (!ret) { 2722 if (colon) 2723 *colon = ':'; 2724 if (copy_to_user(arg, &ifr, 2725 sizeof(struct ifreq))) 2726 ret = -EFAULT; 2727 } 2728 return ret; 2729 2730 /* 2731 * These ioctl calls: 2732 * - require superuser power. 2733 * - require strict serialization. 2734 * - do not return a value 2735 */ 2736 case SIOCSIFFLAGS: 2737 case SIOCSIFMETRIC: 2738 case SIOCSIFMTU: 2739 case SIOCSIFMAP: 2740 case SIOCSIFHWADDR: 2741 case SIOCSIFSLAVE: 2742 case SIOCADDMULTI: 2743 case SIOCDELMULTI: 2744 case SIOCSIFHWBROADCAST: 2745 case SIOCSIFTXQLEN: 2746 case SIOCSMIIREG: 2747 case SIOCBONDENSLAVE: 2748 case SIOCBONDRELEASE: 2749 case SIOCBONDSETHWADDR: 2750 case SIOCBONDCHANGEACTIVE: 2751 case SIOCBRADDIF: 2752 case SIOCBRDELIF: 2753 if (!capable(CAP_NET_ADMIN)) 2754 return -EPERM; 2755 /* fall through */ 2756 case SIOCBONDSLAVEINFOQUERY: 2757 case SIOCBONDINFOQUERY: 2758 dev_load(ifr.ifr_name); 2759 rtnl_lock(); 2760 ret = dev_ifsioc(&ifr, cmd); 2761 rtnl_unlock(); 2762 return ret; 2763 2764 case SIOCGIFMEM: 2765 /* Get the per device memory space. We can add this but 2766 * currently do not support it */ 2767 case SIOCSIFMEM: 2768 /* Set the per device memory buffer space. 2769 * Not applicable in our case */ 2770 case SIOCSIFLINK: 2771 return -EINVAL; 2772 2773 /* 2774 * Unknown or private ioctl. 2775 */ 2776 default: 2777 if (cmd == SIOCWANDEV || 2778 (cmd >= SIOCDEVPRIVATE && 2779 cmd <= SIOCDEVPRIVATE + 15)) { 2780 dev_load(ifr.ifr_name); 2781 rtnl_lock(); 2782 ret = dev_ifsioc(&ifr, cmd); 2783 rtnl_unlock(); 2784 if (!ret && copy_to_user(arg, &ifr, 2785 sizeof(struct ifreq))) 2786 ret = -EFAULT; 2787 return ret; 2788 } 2789#ifdef CONFIG_WIRELESS_EXT 2790 /* Take care of Wireless Extensions */ 2791 if (cmd >= SIOCIWFIRST && cmd <= SIOCIWLAST) { 2792 /* If command is `set a parameter', or 2793 * `get the encoding parameters', check if 2794 * the user has the right to do it */ 2795 if (IW_IS_SET(cmd) || cmd == SIOCGIWENCODE 2796 || cmd == SIOCGIWENCODEEXT) { 2797 if (!capable(CAP_NET_ADMIN)) 2798 return -EPERM; 2799 } 2800 dev_load(ifr.ifr_name); 2801 rtnl_lock(); 2802 /* Follow me in net/core/wireless.c */ 2803 ret = wireless_process_ioctl(&ifr, cmd); 2804 rtnl_unlock(); 2805 if (IW_IS_GET(cmd) && 2806 copy_to_user(arg, &ifr, 2807 sizeof(struct ifreq))) 2808 ret = -EFAULT; 2809 return ret; 2810 } 2811#endif /* CONFIG_WIRELESS_EXT */ 2812 return -EINVAL; 2813 } 2814} 2815 2816 2817/** 2818 * dev_new_index - allocate an ifindex 2819 * 2820 * Returns a suitable unique value for a new device interface 2821 * number. The caller must hold the rtnl semaphore or the 2822 * dev_base_lock to be sure it remains unique. 2823 */ 2824static int dev_new_index(void) 2825{ 2826 static int ifindex; 2827 for (;;) { 2828 if (++ifindex <= 0) 2829 ifindex = 1; 2830 if (!__dev_get_by_index(ifindex)) 2831 return ifindex; 2832 } 2833} 2834 2835static int dev_boot_phase = 1; 2836 2837/* Delayed registration/unregisteration */ 2838static DEFINE_SPINLOCK(net_todo_list_lock); 2839static struct list_head net_todo_list = LIST_HEAD_INIT(net_todo_list); 2840 2841static inline void net_set_todo(struct net_device *dev) 2842{ 2843 spin_lock(&net_todo_list_lock); 2844 list_add_tail(&dev->todo_list, &net_todo_list); 2845 spin_unlock(&net_todo_list_lock); 2846} 2847 2848/** 2849 * register_netdevice - register a network device 2850 * @dev: device to register 2851 * 2852 * Take a completed network device structure and add it to the kernel 2853 * interfaces. A %NETDEV_REGISTER message is sent to the netdev notifier 2854 * chain. 0 is returned on success. A negative errno code is returned 2855 * on a failure to set up the device, or if the name is a duplicate. 2856 * 2857 * Callers must hold the rtnl semaphore. You may want 2858 * register_netdev() instead of this. 2859 * 2860 * BUGS: 2861 * The locking appears insufficient to guarantee two parallel registers 2862 * will not get the same name. 2863 */ 2864 2865int register_netdevice(struct net_device *dev) 2866{ 2867 struct hlist_head *head; 2868 struct hlist_node *p; 2869 int ret; 2870 2871 BUG_ON(dev_boot_phase); 2872 ASSERT_RTNL(); 2873 2874 might_sleep(); 2875 2876 /* When net_device's are persistent, this will be fatal. */ 2877 BUG_ON(dev->reg_state != NETREG_UNINITIALIZED); 2878 2879 spin_lock_init(&dev->queue_lock); 2880 spin_lock_init(&dev->_xmit_lock); 2881 dev->xmit_lock_owner = -1; 2882#ifdef CONFIG_NET_CLS_ACT 2883 spin_lock_init(&dev->ingress_lock); 2884#endif 2885 2886 ret = alloc_divert_blk(dev); 2887 if (ret) 2888 goto out; 2889 2890 dev->iflink = -1; 2891 2892 /* Init, if this function is available */ 2893 if (dev->init) { 2894 ret = dev->init(dev); 2895 if (ret) { 2896 if (ret > 0) 2897 ret = -EIO; 2898 goto out_err; 2899 } 2900 } 2901 2902 if (!dev_valid_name(dev->name)) { 2903 ret = -EINVAL; 2904 goto out_err; 2905 } 2906 2907 dev->ifindex = dev_new_index(); 2908 if (dev->iflink == -1) 2909 dev->iflink = dev->ifindex; 2910 2911 /* Check for existence of name */ 2912 head = dev_name_hash(dev->name); 2913 hlist_for_each(p, head) { 2914 struct net_device *d 2915 = hlist_entry(p, struct net_device, name_hlist); 2916 if (!strncmp(d->name, dev->name, IFNAMSIZ)) { 2917 ret = -EEXIST; 2918 goto out_err; 2919 } 2920 } 2921 2922 /* Fix illegal SG+CSUM combinations. */ 2923 if ((dev->features & NETIF_F_SG) && 2924 !(dev->features & NETIF_F_ALL_CSUM)) { 2925 printk("%s: Dropping NETIF_F_SG since no checksum feature.\n", 2926 dev->name); 2927 dev->features &= ~NETIF_F_SG; 2928 } 2929 2930 /* TSO requires that SG is present as well. */ 2931 if ((dev->features & NETIF_F_TSO) && 2932 !(dev->features & NETIF_F_SG)) { 2933 printk("%s: Dropping NETIF_F_TSO since no SG feature.\n", 2934 dev->name); 2935 dev->features &= ~NETIF_F_TSO; 2936 } 2937 if (dev->features & NETIF_F_UFO) { 2938 if (!(dev->features & NETIF_F_HW_CSUM)) { 2939 printk(KERN_ERR "%s: Dropping NETIF_F_UFO since no " 2940 "NETIF_F_HW_CSUM feature.\n", 2941 dev->name); 2942 dev->features &= ~NETIF_F_UFO; 2943 } 2944 if (!(dev->features & NETIF_F_SG)) { 2945 printk(KERN_ERR "%s: Dropping NETIF_F_UFO since no " 2946 "NETIF_F_SG feature.\n", 2947 dev->name); 2948 dev->features &= ~NETIF_F_UFO; 2949 } 2950 } 2951 2952 /* 2953 * nil rebuild_header routine, 2954 * that should be never called and used as just bug trap. 2955 */ 2956 2957 if (!dev->rebuild_header) 2958 dev->rebuild_header = default_rebuild_header; 2959 2960 ret = netdev_register_sysfs(dev); 2961 if (ret) 2962 goto out_err; 2963 dev->reg_state = NETREG_REGISTERED; 2964 2965 /* 2966 * Default initial state at registry is that the 2967 * device is present. 2968 */ 2969 2970 set_bit(__LINK_STATE_PRESENT, &dev->state); 2971 2972 dev->next = NULL; 2973 dev_init_scheduler(dev); 2974 write_lock_bh(&dev_base_lock); 2975 *dev_tail = dev; 2976 dev_tail = &dev->next; 2977 hlist_add_head(&dev->name_hlist, head); 2978 hlist_add_head(&dev->index_hlist, dev_index_hash(dev->ifindex)); 2979 dev_hold(dev); 2980 write_unlock_bh(&dev_base_lock); 2981 2982 /* Notify protocols, that a new device appeared. */ 2983 raw_notifier_call_chain(&netdev_chain, NETDEV_REGISTER, dev); 2984 2985 ret = 0; 2986 2987out: 2988 return ret; 2989out_err: 2990 free_divert_blk(dev); 2991 goto out; 2992} 2993 2994/** 2995 * register_netdev - register a network device 2996 * @dev: device to register 2997 * 2998 * Take a completed network device structure and add it to the kernel 2999 * interfaces. A %NETDEV_REGISTER message is sent to the netdev notifier 3000 * chain. 0 is returned on success. A negative errno code is returned 3001 * on a failure to set up the device, or if the name is a duplicate. 3002 * 3003 * This is a wrapper around register_netdev that takes the rtnl semaphore 3004 * and expands the device name if you passed a format string to 3005 * alloc_netdev. 3006 */ 3007int register_netdev(struct net_device *dev) 3008{ 3009 int err; 3010 3011 rtnl_lock(); 3012 3013 /* 3014 * If the name is a format string the caller wants us to do a 3015 * name allocation. 3016 */ 3017 if (strchr(dev->name, '%')) { 3018 err = dev_alloc_name(dev, dev->name); 3019 if (err < 0) 3020 goto out; 3021 } 3022 3023 /* 3024 * Back compatibility hook. Kill this one in 2.5 3025 */ 3026 if (dev->name[0] == 0 || dev->name[0] == ' ') { 3027 err = dev_alloc_name(dev, "eth%d"); 3028 if (err < 0) 3029 goto out; 3030 } 3031 3032 err = register_netdevice(dev); 3033out: 3034 rtnl_unlock(); 3035 return err; 3036} 3037EXPORT_SYMBOL(register_netdev); 3038 3039/* 3040 * netdev_wait_allrefs - wait until all references are gone. 3041 * 3042 * This is called when unregistering network devices. 3043 * 3044 * Any protocol or device that holds a reference should register 3045 * for netdevice notification, and cleanup and put back the 3046 * reference if they receive an UNREGISTER event. 3047 * We can get stuck here if buggy protocols don't correctly 3048 * call dev_put. 3049 */ 3050static void netdev_wait_allrefs(struct net_device *dev) 3051{ 3052 unsigned long rebroadcast_time, warning_time; 3053 3054 rebroadcast_time = warning_time = jiffies; 3055 while (atomic_read(&dev->refcnt) != 0) { 3056 if (time_after(jiffies, rebroadcast_time + 1 * HZ)) { 3057 rtnl_lock(); 3058 3059 /* Rebroadcast unregister notification */ 3060 raw_notifier_call_chain(&netdev_chain, 3061 NETDEV_UNREGISTER, dev); 3062 3063 if (test_bit(__LINK_STATE_LINKWATCH_PENDING, 3064 &dev->state)) { 3065 /* We must not have linkwatch events 3066 * pending on unregister. If this 3067 * happens, we simply run the queue 3068 * unscheduled, resulting in a noop 3069 * for this device. 3070 */ 3071 linkwatch_run_queue(); 3072 } 3073 3074 __rtnl_unlock(); 3075 3076 rebroadcast_time = jiffies; 3077 } 3078 3079 msleep(250); 3080 3081 if (time_after(jiffies, warning_time + 10 * HZ)) { 3082 printk(KERN_EMERG "unregister_netdevice: " 3083 "waiting for %s to become free. Usage " 3084 "count = %d\n", 3085 dev->name, atomic_read(&dev->refcnt)); 3086 warning_time = jiffies; 3087 } 3088 } 3089} 3090 3091/* The sequence is: 3092 * 3093 * rtnl_lock(); 3094 * ... 3095 * register_netdevice(x1); 3096 * register_netdevice(x2); 3097 * ... 3098 * unregister_netdevice(y1); 3099 * unregister_netdevice(y2); 3100 * ... 3101 * rtnl_unlock(); 3102 * free_netdev(y1); 3103 * free_netdev(y2); 3104 * 3105 * We are invoked by rtnl_unlock() after it drops the semaphore. 3106 * This allows us to deal with problems: 3107 * 1) We can delete sysfs objects which invoke hotplug 3108 * without deadlocking with linkwatch via keventd. 3109 * 2) Since we run with the RTNL semaphore not held, we can sleep 3110 * safely in order to wait for the netdev refcnt to drop to zero. 3111 */ 3112static DEFINE_MUTEX(net_todo_run_mutex); 3113void netdev_run_todo(void) 3114{ 3115 struct list_head list; 3116 3117 /* Need to guard against multiple cpu's getting out of order. */ 3118 mutex_lock(&net_todo_run_mutex); 3119 3120 /* Not safe to do outside the semaphore. We must not return 3121 * until all unregister events invoked by the local processor 3122 * have been completed (either by this todo run, or one on 3123 * another cpu). 3124 */ 3125 if (list_empty(&net_todo_list)) 3126 goto out; 3127 3128 /* Snapshot list, allow later requests */ 3129 spin_lock(&net_todo_list_lock); 3130 list_replace_init(&net_todo_list, &list); 3131 spin_unlock(&net_todo_list_lock); 3132 3133 while (!list_empty(&list)) { 3134 struct net_device *dev 3135 = list_entry(list.next, struct net_device, todo_list); 3136 list_del(&dev->todo_list); 3137 3138 if (unlikely(dev->reg_state != NETREG_UNREGISTERING)) { 3139 printk(KERN_ERR "network todo '%s' but state %d\n", 3140 dev->name, dev->reg_state); 3141 dump_stack(); 3142 continue; 3143 } 3144 3145 netdev_unregister_sysfs(dev); 3146 dev->reg_state = NETREG_UNREGISTERED; 3147 3148 netdev_wait_allrefs(dev); 3149 3150 /* paranoia */ 3151 BUG_ON(atomic_read(&dev->refcnt)); 3152 BUG_TRAP(!dev->ip_ptr); 3153 BUG_TRAP(!dev->ip6_ptr); 3154 BUG_TRAP(!dev->dn_ptr); 3155 3156 /* It must be the very last action, 3157 * after this 'dev' may point to freed up memory. 3158 */ 3159 if (dev->destructor) 3160 dev->destructor(dev); 3161 } 3162 3163out: 3164 mutex_unlock(&net_todo_run_mutex); 3165} 3166 3167/** 3168 * alloc_netdev - allocate network device 3169 * @sizeof_priv: size of private data to allocate space for 3170 * @name: device name format string 3171 * @setup: callback to initialize device 3172 * 3173 * Allocates a struct net_device with private data area for driver use 3174 * and performs basic initialization. 3175 */ 3176struct net_device *alloc_netdev(int sizeof_priv, const char *name, 3177 void (*setup)(struct net_device *)) 3178{ 3179 void *p; 3180 struct net_device *dev; 3181 int alloc_size; 3182 3183 /* ensure 32-byte alignment of both the device and private area */ 3184 alloc_size = (sizeof(*dev) + NETDEV_ALIGN_CONST) & ~NETDEV_ALIGN_CONST; 3185 alloc_size += sizeof_priv + NETDEV_ALIGN_CONST; 3186 3187 p = kzalloc(alloc_size, GFP_KERNEL); 3188 if (!p) { 3189 printk(KERN_ERR "alloc_dev: Unable to allocate device.\n"); 3190 return NULL; 3191 } 3192 3193 dev = (struct net_device *) 3194 (((long)p + NETDEV_ALIGN_CONST) & ~NETDEV_ALIGN_CONST); 3195 dev->padded = (char *)dev - (char *)p; 3196 3197 if (sizeof_priv) 3198 dev->priv = netdev_priv(dev); 3199 3200 setup(dev); 3201 strcpy(dev->name, name); 3202 return dev; 3203} 3204EXPORT_SYMBOL(alloc_netdev); 3205 3206/** 3207 * free_netdev - free network device 3208 * @dev: device 3209 * 3210 * This function does the last stage of destroying an allocated device 3211 * interface. The reference to the device object is released. 3212 * If this is the last reference then it will be freed. 3213 */ 3214void free_netdev(struct net_device *dev) 3215{ 3216#ifdef CONFIG_SYSFS 3217 /* Compatibility with error handling in drivers */ 3218 if (dev->reg_state == NETREG_UNINITIALIZED) { 3219 kfree((char *)dev - dev->padded); 3220 return; 3221 } 3222 3223 BUG_ON(dev->reg_state != NETREG_UNREGISTERED); 3224 dev->reg_state = NETREG_RELEASED; 3225 3226 /* will free via class release */ 3227 class_device_put(&dev->class_dev); 3228#else 3229 kfree((char *)dev - dev->padded); 3230#endif 3231} 3232 3233/* Synchronize with packet receive processing. */ 3234void synchronize_net(void) 3235{ 3236 might_sleep(); 3237 synchronize_rcu(); 3238} 3239 3240/** 3241 * unregister_netdevice - remove device from the kernel 3242 * @dev: device 3243 * 3244 * This function shuts down a device interface and removes it 3245 * from the kernel tables. On success 0 is returned, on a failure 3246 * a negative errno code is returned. 3247 * 3248 * Callers must hold the rtnl semaphore. You may want 3249 * unregister_netdev() instead of this. 3250 */ 3251 3252int unregister_netdevice(struct net_device *dev) 3253{ 3254 struct net_device *d, **dp; 3255 3256 BUG_ON(dev_boot_phase); 3257 ASSERT_RTNL(); 3258 3259 /* Some devices call without registering for initialization unwind. */ 3260 if (dev->reg_state == NETREG_UNINITIALIZED) { 3261 printk(KERN_DEBUG "unregister_netdevice: device %s/%p never " 3262 "was registered\n", dev->name, dev); 3263 return -ENODEV; 3264 } 3265 3266 BUG_ON(dev->reg_state != NETREG_REGISTERED); 3267 3268 /* If device is running, close it first. */ 3269 if (dev->flags & IFF_UP) 3270 dev_close(dev); 3271 3272 /* And unlink it from device chain. */ 3273 for (dp = &dev_base; (d = *dp) != NULL; dp = &d->next) { 3274 if (d == dev) { 3275 write_lock_bh(&dev_base_lock); 3276 hlist_del(&dev->name_hlist); 3277 hlist_del(&dev->index_hlist); 3278 if (dev_tail == &dev->next) 3279 dev_tail = dp; 3280 *dp = d->next; 3281 write_unlock_bh(&dev_base_lock); 3282 break; 3283 } 3284 } 3285 if (!d) { 3286 printk(KERN_ERR "unregister net_device: '%s' not found\n", 3287 dev->name); 3288 return -ENODEV; 3289 } 3290 3291 dev->reg_state = NETREG_UNREGISTERING; 3292 3293 synchronize_net(); 3294 3295 /* Shutdown queueing discipline. */ 3296 dev_shutdown(dev); 3297 3298 3299 /* Notify protocols, that we are about to destroy 3300 this device. They should clean all the things. 3301 */ 3302 raw_notifier_call_chain(&netdev_chain, NETDEV_UNREGISTER, dev); 3303 3304 /* 3305 * Flush the multicast chain 3306 */ 3307 dev_mc_discard(dev); 3308 3309 if (dev->uninit) 3310 dev->uninit(dev); 3311 3312 /* Notifier chain MUST detach us from master device. */ 3313 BUG_TRAP(!dev->master); 3314 3315 free_divert_blk(dev); 3316 3317 /* Finish processing unregister after unlock */ 3318 net_set_todo(dev); 3319 3320 synchronize_net(); 3321 3322 dev_put(dev); 3323 return 0; 3324} 3325 3326/** 3327 * unregister_netdev - remove device from the kernel 3328 * @dev: device 3329 * 3330 * This function shuts down a device interface and removes it 3331 * from the kernel tables. On success 0 is returned, on a failure 3332 * a negative errno code is returned. 3333 * 3334 * This is just a wrapper for unregister_netdevice that takes 3335 * the rtnl semaphore. In general you want to use this and not 3336 * unregister_netdevice. 3337 */ 3338void unregister_netdev(struct net_device *dev) 3339{ 3340 rtnl_lock(); 3341 unregister_netdevice(dev); 3342 rtnl_unlock(); 3343} 3344 3345EXPORT_SYMBOL(unregister_netdev); 3346 3347#ifdef CONFIG_HOTPLUG_CPU 3348static int dev_cpu_callback(struct notifier_block *nfb, 3349 unsigned long action, 3350 void *ocpu) 3351{ 3352 struct sk_buff **list_skb; 3353 struct net_device **list_net; 3354 struct sk_buff *skb; 3355 unsigned int cpu, oldcpu = (unsigned long)ocpu; 3356 struct softnet_data *sd, *oldsd; 3357 3358 if (action != CPU_DEAD) 3359 return NOTIFY_OK; 3360 3361 local_irq_disable(); 3362 cpu = smp_processor_id(); 3363 sd = &per_cpu(softnet_data, cpu); 3364 oldsd = &per_cpu(softnet_data, oldcpu); 3365 3366 /* Find end of our completion_queue. */ 3367 list_skb = &sd->completion_queue; 3368 while (*list_skb) 3369 list_skb = &(*list_skb)->next; 3370 /* Append completion queue from offline CPU. */ 3371 *list_skb = oldsd->completion_queue; 3372 oldsd->completion_queue = NULL; 3373 3374 /* Find end of our output_queue. */ 3375 list_net = &sd->output_queue; 3376 while (*list_net) 3377 list_net = &(*list_net)->next_sched; 3378 /* Append output queue from offline CPU. */ 3379 *list_net = oldsd->output_queue; 3380 oldsd->output_queue = NULL; 3381 3382 raise_softirq_irqoff(NET_TX_SOFTIRQ); 3383 local_irq_enable(); 3384 3385 /* Process offline CPU's input_pkt_queue */ 3386 while ((skb = __skb_dequeue(&oldsd->input_pkt_queue))) 3387 netif_rx(skb); 3388 3389 return NOTIFY_OK; 3390} 3391#endif /* CONFIG_HOTPLUG_CPU */ 3392 3393#ifdef CONFIG_NET_DMA 3394/** 3395 * net_dma_rebalance - 3396 * This is called when the number of channels allocated to the net_dma_client 3397 * changes. The net_dma_client tries to have one DMA channel per CPU. 3398 */ 3399static void net_dma_rebalance(void) 3400{ 3401 unsigned int cpu, i, n; 3402 struct dma_chan *chan; 3403 3404 lock_cpu_hotplug(); 3405 3406 if (net_dma_count == 0) { 3407 for_each_online_cpu(cpu) 3408 rcu_assign_pointer(per_cpu(softnet_data.net_dma, cpu), NULL); 3409 unlock_cpu_hotplug(); 3410 return; 3411 } 3412 3413 i = 0; 3414 cpu = first_cpu(cpu_online_map); 3415 3416 rcu_read_lock(); 3417 list_for_each_entry(chan, &net_dma_client->channels, client_node) { 3418 n = ((num_online_cpus() / net_dma_count) 3419 + (i < (num_online_cpus() % net_dma_count) ? 1 : 0)); 3420 3421 while(n) { 3422 per_cpu(softnet_data.net_dma, cpu) = chan; 3423 cpu = next_cpu(cpu, cpu_online_map); 3424 n--; 3425 } 3426 i++; 3427 } 3428 rcu_read_unlock(); 3429 3430 unlock_cpu_hotplug(); 3431} 3432 3433/** 3434 * netdev_dma_event - event callback for the net_dma_client 3435 * @client: should always be net_dma_client 3436 * @chan: DMA channel for the event 3437 * @event: event type 3438 */ 3439static void netdev_dma_event(struct dma_client *client, struct dma_chan *chan, 3440 enum dma_event event) 3441{ 3442 spin_lock(&net_dma_event_lock); 3443 switch (event) { 3444 case DMA_RESOURCE_ADDED: 3445 net_dma_count++; 3446 net_dma_rebalance(); 3447 break; 3448 case DMA_RESOURCE_REMOVED: 3449 net_dma_count--; 3450 net_dma_rebalance(); 3451 break; 3452 default: 3453 break; 3454 } 3455 spin_unlock(&net_dma_event_lock); 3456} 3457 3458/** 3459 * netdev_dma_regiser - register the networking subsystem as a DMA client 3460 */ 3461static int __init netdev_dma_register(void) 3462{ 3463 spin_lock_init(&net_dma_event_lock); 3464 net_dma_client = dma_async_client_register(netdev_dma_event); 3465 if (net_dma_client == NULL) 3466 return -ENOMEM; 3467 3468 dma_async_client_chan_request(net_dma_client, num_online_cpus()); 3469 return 0; 3470} 3471 3472#else 3473static int __init netdev_dma_register(void) { return -ENODEV; } 3474#endif /* CONFIG_NET_DMA */ 3475 3476/* 3477 * Initialize the DEV module. At boot time this walks the device list and 3478 * unhooks any devices that fail to initialise (normally hardware not 3479 * present) and leaves us with a valid list of present and active devices. 3480 * 3481 */ 3482 3483/* 3484 * This is called single threaded during boot, so no need 3485 * to take the rtnl semaphore. 3486 */ 3487static int __init net_dev_init(void) 3488{ 3489 int i, rc = -ENOMEM; 3490 3491 BUG_ON(!dev_boot_phase); 3492 3493 net_random_init(); 3494 3495 if (dev_proc_init()) 3496 goto out; 3497 3498 if (netdev_sysfs_init()) 3499 goto out; 3500 3501 INIT_LIST_HEAD(&ptype_all); 3502 for (i = 0; i < 16; i++) 3503 INIT_LIST_HEAD(&ptype_base[i]); 3504 3505 for (i = 0; i < ARRAY_SIZE(dev_name_head); i++) 3506 INIT_HLIST_HEAD(&dev_name_head[i]); 3507 3508 for (i = 0; i < ARRAY_SIZE(dev_index_head); i++) 3509 INIT_HLIST_HEAD(&dev_index_head[i]); 3510 3511 /* 3512 * Initialise the packet receive queues. 3513 */ 3514 3515 for_each_possible_cpu(i) { 3516 struct softnet_data *queue; 3517 3518 queue = &per_cpu(softnet_data, i); 3519 skb_queue_head_init(&queue->input_pkt_queue); 3520 queue->completion_queue = NULL; 3521 INIT_LIST_HEAD(&queue->poll_list); 3522 set_bit(__LINK_STATE_START, &queue->backlog_dev.state); 3523 queue->backlog_dev.weight = weight_p; 3524 queue->backlog_dev.poll = process_backlog; 3525 atomic_set(&queue->backlog_dev.refcnt, 1); 3526 } 3527 3528 netdev_dma_register(); 3529 3530 dev_boot_phase = 0; 3531 3532 open_softirq(NET_TX_SOFTIRQ, net_tx_action, NULL); 3533 open_softirq(NET_RX_SOFTIRQ, net_rx_action, NULL); 3534 3535 hotcpu_notifier(dev_cpu_callback, 0); 3536 dst_init(); 3537 dev_mcast_init(); 3538 rc = 0; 3539out: 3540 return rc; 3541} 3542 3543subsys_initcall(net_dev_init); 3544 3545EXPORT_SYMBOL(__dev_get_by_index); 3546EXPORT_SYMBOL(__dev_get_by_name); 3547EXPORT_SYMBOL(__dev_remove_pack); 3548EXPORT_SYMBOL(dev_valid_name); 3549EXPORT_SYMBOL(dev_add_pack); 3550EXPORT_SYMBOL(dev_alloc_name); 3551EXPORT_SYMBOL(dev_close); 3552EXPORT_SYMBOL(dev_get_by_flags); 3553EXPORT_SYMBOL(dev_get_by_index); 3554EXPORT_SYMBOL(dev_get_by_name); 3555EXPORT_SYMBOL(dev_open); 3556EXPORT_SYMBOL(dev_queue_xmit); 3557EXPORT_SYMBOL(dev_remove_pack); 3558EXPORT_SYMBOL(dev_set_allmulti); 3559EXPORT_SYMBOL(dev_set_promiscuity); 3560EXPORT_SYMBOL(dev_change_flags); 3561EXPORT_SYMBOL(dev_set_mtu); 3562EXPORT_SYMBOL(dev_set_mac_address); 3563EXPORT_SYMBOL(free_netdev); 3564EXPORT_SYMBOL(netdev_boot_setup_check); 3565EXPORT_SYMBOL(netdev_set_master); 3566EXPORT_SYMBOL(netdev_state_change); 3567EXPORT_SYMBOL(netif_receive_skb); 3568EXPORT_SYMBOL(netif_rx); 3569EXPORT_SYMBOL(register_gifconf); 3570EXPORT_SYMBOL(register_netdevice); 3571EXPORT_SYMBOL(register_netdevice_notifier); 3572EXPORT_SYMBOL(skb_checksum_help); 3573EXPORT_SYMBOL(synchronize_net); 3574EXPORT_SYMBOL(unregister_netdevice); 3575EXPORT_SYMBOL(unregister_netdevice_notifier); 3576EXPORT_SYMBOL(net_enable_timestamp); 3577EXPORT_SYMBOL(net_disable_timestamp); 3578EXPORT_SYMBOL(dev_get_flags); 3579 3580#if defined(CONFIG_BRIDGE) || defined(CONFIG_BRIDGE_MODULE) 3581EXPORT_SYMBOL(br_handle_frame_hook); 3582EXPORT_SYMBOL(br_fdb_get_hook); 3583EXPORT_SYMBOL(br_fdb_put_hook); 3584#endif 3585 3586#ifdef CONFIG_KMOD 3587EXPORT_SYMBOL(dev_load); 3588#endif 3589 3590EXPORT_PER_CPU_SYMBOL(softnet_data);