2 * NET3 Protocol independent device support routines.
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.
9 * Derived from the non IP parts of dev.c 1.0.19
11 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
12 * Mark Evans, <evansmp@uhura.aston.ac.uk>
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>
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
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
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
51 * Rudi Cilibrasi : Pass the right thing to
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
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
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
75 #include <asm/uaccess.h>
76 #include <asm/system.h>
77 #include <linux/bitops.h>
78 #include <linux/capability.h>
79 #include <linux/cpu.h>
80 #include <linux/types.h>
81 #include <linux/kernel.h>
82 #include <linux/hash.h>
83 #include <linux/slab.h>
84 #include <linux/sched.h>
85 #include <linux/mutex.h>
86 #include <linux/string.h>
88 #include <linux/socket.h>
89 #include <linux/sockios.h>
90 #include <linux/errno.h>
91 #include <linux/interrupt.h>
92 #include <linux/if_ether.h>
93 #include <linux/netdevice.h>
94 #include <linux/etherdevice.h>
95 #include <linux/ethtool.h>
96 #include <linux/notifier.h>
97 #include <linux/skbuff.h>
98 #include <net/net_namespace.h>
100 #include <linux/rtnetlink.h>
101 #include <linux/proc_fs.h>
102 #include <linux/seq_file.h>
103 #include <linux/stat.h>
105 #include <net/pkt_sched.h>
106 #include <net/checksum.h>
107 #include <net/xfrm.h>
108 #include <linux/highmem.h>
109 #include <linux/init.h>
110 #include <linux/kmod.h>
111 #include <linux/module.h>
112 #include <linux/netpoll.h>
113 #include <linux/rcupdate.h>
114 #include <linux/delay.h>
115 #include <net/wext.h>
116 #include <net/iw_handler.h>
117 #include <asm/current.h>
118 #include <linux/audit.h>
119 #include <linux/dmaengine.h>
120 #include <linux/err.h>
121 #include <linux/ctype.h>
122 #include <linux/if_arp.h>
123 #include <linux/if_vlan.h>
124 #include <linux/ip.h>
126 #include <linux/ipv6.h>
127 #include <linux/in.h>
128 #include <linux/jhash.h>
129 #include <linux/random.h>
130 #include <trace/events/napi.h>
131 #include <trace/events/net.h>
132 #include <trace/events/skb.h>
133 #include <linux/pci.h>
134 #include <linux/inetdevice.h>
136 #include "net-sysfs.h"
138 /* Instead of increasing this, you should create a hash table. */
139 #define MAX_GRO_SKBS 8
141 /* This should be increased if a protocol with a bigger head is added. */
142 #define GRO_MAX_HEAD (MAX_HEADER + 128)
145 * The list of packet types we will receive (as opposed to discard)
146 * and the routines to invoke.
148 * Why 16. Because with 16 the only overlap we get on a hash of the
149 * low nibble of the protocol value is RARP/SNAP/X.25.
151 * NOTE: That is no longer true with the addition of VLAN tags. Not
152 * sure which should go first, but I bet it won't make much
153 * difference if we are running VLANs. The good news is that
154 * this protocol won't be in the list unless compiled in, so
155 * the average user (w/out VLANs) will not be adversely affected.
172 #define PTYPE_HASH_SIZE (16)
173 #define PTYPE_HASH_MASK (PTYPE_HASH_SIZE - 1)
175 static DEFINE_SPINLOCK(ptype_lock);
176 static struct list_head ptype_base[PTYPE_HASH_SIZE] __read_mostly;
177 static struct list_head ptype_all __read_mostly; /* Taps */
180 * The @dev_base_head list is protected by @dev_base_lock and the rtnl
183 * Pure readers hold dev_base_lock for reading, or rcu_read_lock()
185 * Writers must hold the rtnl semaphore while they loop through the
186 * dev_base_head list, and hold dev_base_lock for writing when they do the
187 * actual updates. This allows pure readers to access the list even
188 * while a writer is preparing to update it.
190 * To put it another way, dev_base_lock is held for writing only to
191 * protect against pure readers; the rtnl semaphore provides the
192 * protection against other writers.
194 * See, for example usages, register_netdevice() and
195 * unregister_netdevice(), which must be called with the rtnl
198 DEFINE_RWLOCK(dev_base_lock);
199 EXPORT_SYMBOL(dev_base_lock);
201 static inline struct hlist_head *dev_name_hash(struct net *net, const char *name)
203 unsigned hash = full_name_hash(name, strnlen(name, IFNAMSIZ));
204 return &net->dev_name_head[hash_32(hash, NETDEV_HASHBITS)];
207 static inline struct hlist_head *dev_index_hash(struct net *net, int ifindex)
209 return &net->dev_index_head[ifindex & (NETDEV_HASHENTRIES - 1)];
212 static inline void rps_lock(struct softnet_data *sd)
215 spin_lock(&sd->input_pkt_queue.lock);
219 static inline void rps_unlock(struct softnet_data *sd)
222 spin_unlock(&sd->input_pkt_queue.lock);
226 /* Device list insertion */
227 static int list_netdevice(struct net_device *dev)
229 struct net *net = dev_net(dev);
233 write_lock_bh(&dev_base_lock);
234 list_add_tail_rcu(&dev->dev_list, &net->dev_base_head);
235 hlist_add_head_rcu(&dev->name_hlist, dev_name_hash(net, dev->name));
236 hlist_add_head_rcu(&dev->index_hlist,
237 dev_index_hash(net, dev->ifindex));
238 write_unlock_bh(&dev_base_lock);
242 /* Device list removal
243 * caller must respect a RCU grace period before freeing/reusing dev
245 static void unlist_netdevice(struct net_device *dev)
249 /* Unlink dev from the device chain */
250 write_lock_bh(&dev_base_lock);
251 list_del_rcu(&dev->dev_list);
252 hlist_del_rcu(&dev->name_hlist);
253 hlist_del_rcu(&dev->index_hlist);
254 write_unlock_bh(&dev_base_lock);
261 static RAW_NOTIFIER_HEAD(netdev_chain);
264 * Device drivers call our routines to queue packets here. We empty the
265 * queue in the local softnet handler.
268 DEFINE_PER_CPU_ALIGNED(struct softnet_data, softnet_data);
269 EXPORT_PER_CPU_SYMBOL(softnet_data);
271 #ifdef CONFIG_LOCKDEP
273 * register_netdevice() inits txq->_xmit_lock and sets lockdep class
274 * according to dev->type
276 static const unsigned short netdev_lock_type[] =
277 {ARPHRD_NETROM, ARPHRD_ETHER, ARPHRD_EETHER, ARPHRD_AX25,
278 ARPHRD_PRONET, ARPHRD_CHAOS, ARPHRD_IEEE802, ARPHRD_ARCNET,
279 ARPHRD_APPLETLK, ARPHRD_DLCI, ARPHRD_ATM, ARPHRD_METRICOM,
280 ARPHRD_IEEE1394, ARPHRD_EUI64, ARPHRD_INFINIBAND, ARPHRD_SLIP,
281 ARPHRD_CSLIP, ARPHRD_SLIP6, ARPHRD_CSLIP6, ARPHRD_RSRVD,
282 ARPHRD_ADAPT, ARPHRD_ROSE, ARPHRD_X25, ARPHRD_HWX25,
283 ARPHRD_PPP, ARPHRD_CISCO, ARPHRD_LAPB, ARPHRD_DDCMP,
284 ARPHRD_RAWHDLC, ARPHRD_TUNNEL, ARPHRD_TUNNEL6, ARPHRD_FRAD,
285 ARPHRD_SKIP, ARPHRD_LOOPBACK, ARPHRD_LOCALTLK, ARPHRD_FDDI,
286 ARPHRD_BIF, ARPHRD_SIT, ARPHRD_IPDDP, ARPHRD_IPGRE,
287 ARPHRD_PIMREG, ARPHRD_HIPPI, ARPHRD_ASH, ARPHRD_ECONET,
288 ARPHRD_IRDA, ARPHRD_FCPP, ARPHRD_FCAL, ARPHRD_FCPL,
289 ARPHRD_FCFABRIC, ARPHRD_IEEE802_TR, ARPHRD_IEEE80211,
290 ARPHRD_IEEE80211_PRISM, ARPHRD_IEEE80211_RADIOTAP, ARPHRD_PHONET,
291 ARPHRD_PHONET_PIPE, ARPHRD_IEEE802154,
292 ARPHRD_VOID, ARPHRD_NONE};
294 static const char *const netdev_lock_name[] =
295 {"_xmit_NETROM", "_xmit_ETHER", "_xmit_EETHER", "_xmit_AX25",
296 "_xmit_PRONET", "_xmit_CHAOS", "_xmit_IEEE802", "_xmit_ARCNET",
297 "_xmit_APPLETLK", "_xmit_DLCI", "_xmit_ATM", "_xmit_METRICOM",
298 "_xmit_IEEE1394", "_xmit_EUI64", "_xmit_INFINIBAND", "_xmit_SLIP",
299 "_xmit_CSLIP", "_xmit_SLIP6", "_xmit_CSLIP6", "_xmit_RSRVD",
300 "_xmit_ADAPT", "_xmit_ROSE", "_xmit_X25", "_xmit_HWX25",
301 "_xmit_PPP", "_xmit_CISCO", "_xmit_LAPB", "_xmit_DDCMP",
302 "_xmit_RAWHDLC", "_xmit_TUNNEL", "_xmit_TUNNEL6", "_xmit_FRAD",
303 "_xmit_SKIP", "_xmit_LOOPBACK", "_xmit_LOCALTLK", "_xmit_FDDI",
304 "_xmit_BIF", "_xmit_SIT", "_xmit_IPDDP", "_xmit_IPGRE",
305 "_xmit_PIMREG", "_xmit_HIPPI", "_xmit_ASH", "_xmit_ECONET",
306 "_xmit_IRDA", "_xmit_FCPP", "_xmit_FCAL", "_xmit_FCPL",
307 "_xmit_FCFABRIC", "_xmit_IEEE802_TR", "_xmit_IEEE80211",
308 "_xmit_IEEE80211_PRISM", "_xmit_IEEE80211_RADIOTAP", "_xmit_PHONET",
309 "_xmit_PHONET_PIPE", "_xmit_IEEE802154",
310 "_xmit_VOID", "_xmit_NONE"};
312 static struct lock_class_key netdev_xmit_lock_key[ARRAY_SIZE(netdev_lock_type)];
313 static struct lock_class_key netdev_addr_lock_key[ARRAY_SIZE(netdev_lock_type)];
315 static inline unsigned short netdev_lock_pos(unsigned short dev_type)
319 for (i = 0; i < ARRAY_SIZE(netdev_lock_type); i++)
320 if (netdev_lock_type[i] == dev_type)
322 /* the last key is used by default */
323 return ARRAY_SIZE(netdev_lock_type) - 1;
326 static inline void netdev_set_xmit_lockdep_class(spinlock_t *lock,
327 unsigned short dev_type)
331 i = netdev_lock_pos(dev_type);
332 lockdep_set_class_and_name(lock, &netdev_xmit_lock_key[i],
333 netdev_lock_name[i]);
336 static inline void netdev_set_addr_lockdep_class(struct net_device *dev)
340 i = netdev_lock_pos(dev->type);
341 lockdep_set_class_and_name(&dev->addr_list_lock,
342 &netdev_addr_lock_key[i],
343 netdev_lock_name[i]);
346 static inline void netdev_set_xmit_lockdep_class(spinlock_t *lock,
347 unsigned short dev_type)
350 static inline void netdev_set_addr_lockdep_class(struct net_device *dev)
355 /*******************************************************************************
357 Protocol management and registration routines
359 *******************************************************************************/
362 * Add a protocol ID to the list. Now that the input handler is
363 * smarter we can dispense with all the messy stuff that used to be
366 * BEWARE!!! Protocol handlers, mangling input packets,
367 * MUST BE last in hash buckets and checking protocol handlers
368 * MUST start from promiscuous ptype_all chain in net_bh.
369 * It is true now, do not change it.
370 * Explanation follows: if protocol handler, mangling packet, will
371 * be the first on list, it is not able to sense, that packet
372 * is cloned and should be copied-on-write, so that it will
373 * change it and subsequent readers will get broken packet.
377 static inline struct list_head *ptype_head(const struct packet_type *pt)
379 if (pt->type == htons(ETH_P_ALL))
382 return &ptype_base[ntohs(pt->type) & PTYPE_HASH_MASK];
386 * dev_add_pack - add packet handler
387 * @pt: packet type declaration
389 * Add a protocol handler to the networking stack. The passed &packet_type
390 * is linked into kernel lists and may not be freed until it has been
391 * removed from the kernel lists.
393 * This call does not sleep therefore it can not
394 * guarantee all CPU's that are in middle of receiving packets
395 * will see the new packet type (until the next received packet).
398 void dev_add_pack(struct packet_type *pt)
400 struct list_head *head = ptype_head(pt);
402 spin_lock(&ptype_lock);
403 list_add_rcu(&pt->list, head);
404 spin_unlock(&ptype_lock);
406 EXPORT_SYMBOL(dev_add_pack);
409 * __dev_remove_pack - remove packet handler
410 * @pt: packet type declaration
412 * Remove a protocol handler that was previously added to the kernel
413 * protocol handlers by dev_add_pack(). The passed &packet_type is removed
414 * from the kernel lists and can be freed or reused once this function
417 * The packet type might still be in use by receivers
418 * and must not be freed until after all the CPU's have gone
419 * through a quiescent state.
421 void __dev_remove_pack(struct packet_type *pt)
423 struct list_head *head = ptype_head(pt);
424 struct packet_type *pt1;
426 spin_lock(&ptype_lock);
428 list_for_each_entry(pt1, head, list) {
430 list_del_rcu(&pt->list);
435 printk(KERN_WARNING "dev_remove_pack: %p not found.\n", pt);
437 spin_unlock(&ptype_lock);
439 EXPORT_SYMBOL(__dev_remove_pack);
442 * dev_remove_pack - remove packet handler
443 * @pt: packet type declaration
445 * Remove a protocol handler that was previously added to the kernel
446 * protocol handlers by dev_add_pack(). The passed &packet_type is removed
447 * from the kernel lists and can be freed or reused once this function
450 * This call sleeps to guarantee that no CPU is looking at the packet
453 void dev_remove_pack(struct packet_type *pt)
455 __dev_remove_pack(pt);
459 EXPORT_SYMBOL(dev_remove_pack);
461 /******************************************************************************
463 Device Boot-time Settings Routines
465 *******************************************************************************/
467 /* Boot time configuration table */
468 static struct netdev_boot_setup dev_boot_setup[NETDEV_BOOT_SETUP_MAX];
471 * netdev_boot_setup_add - add new setup entry
472 * @name: name of the device
473 * @map: configured settings for the device
475 * Adds new setup entry to the dev_boot_setup list. The function
476 * returns 0 on error and 1 on success. This is a generic routine to
479 static int netdev_boot_setup_add(char *name, struct ifmap *map)
481 struct netdev_boot_setup *s;
485 for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++) {
486 if (s[i].name[0] == '\0' || s[i].name[0] == ' ') {
487 memset(s[i].name, 0, sizeof(s[i].name));
488 strlcpy(s[i].name, name, IFNAMSIZ);
489 memcpy(&s[i].map, map, sizeof(s[i].map));
494 return i >= NETDEV_BOOT_SETUP_MAX ? 0 : 1;
498 * netdev_boot_setup_check - check boot time settings
499 * @dev: the netdevice
501 * Check boot time settings for the device.
502 * The found settings are set for the device to be used
503 * later in the device probing.
504 * Returns 0 if no settings found, 1 if they are.
506 int netdev_boot_setup_check(struct net_device *dev)
508 struct netdev_boot_setup *s = dev_boot_setup;
511 for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++) {
512 if (s[i].name[0] != '\0' && s[i].name[0] != ' ' &&
513 !strcmp(dev->name, s[i].name)) {
514 dev->irq = s[i].map.irq;
515 dev->base_addr = s[i].map.base_addr;
516 dev->mem_start = s[i].map.mem_start;
517 dev->mem_end = s[i].map.mem_end;
523 EXPORT_SYMBOL(netdev_boot_setup_check);
527 * netdev_boot_base - get address from boot time settings
528 * @prefix: prefix for network device
529 * @unit: id for network device
531 * Check boot time settings for the base address of device.
532 * The found settings are set for the device to be used
533 * later in the device probing.
534 * Returns 0 if no settings found.
536 unsigned long netdev_boot_base(const char *prefix, int unit)
538 const struct netdev_boot_setup *s = dev_boot_setup;
542 sprintf(name, "%s%d", prefix, unit);
545 * If device already registered then return base of 1
546 * to indicate not to probe for this interface
548 if (__dev_get_by_name(&init_net, name))
551 for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++)
552 if (!strcmp(name, s[i].name))
553 return s[i].map.base_addr;
558 * Saves at boot time configured settings for any netdevice.
560 int __init netdev_boot_setup(char *str)
565 str = get_options(str, ARRAY_SIZE(ints), ints);
570 memset(&map, 0, sizeof(map));
574 map.base_addr = ints[2];
576 map.mem_start = ints[3];
578 map.mem_end = ints[4];
580 /* Add new entry to the list */
581 return netdev_boot_setup_add(str, &map);
584 __setup("netdev=", netdev_boot_setup);
586 /*******************************************************************************
588 Device Interface Subroutines
590 *******************************************************************************/
593 * __dev_get_by_name - find a device by its name
594 * @net: the applicable net namespace
595 * @name: name to find
597 * Find an interface by name. Must be called under RTNL semaphore
598 * or @dev_base_lock. If the name is found a pointer to the device
599 * is returned. If the name is not found then %NULL is returned. The
600 * reference counters are not incremented so the caller must be
601 * careful with locks.
604 struct net_device *__dev_get_by_name(struct net *net, const char *name)
606 struct hlist_node *p;
607 struct net_device *dev;
608 struct hlist_head *head = dev_name_hash(net, name);
610 hlist_for_each_entry(dev, p, head, name_hlist)
611 if (!strncmp(dev->name, name, IFNAMSIZ))
616 EXPORT_SYMBOL(__dev_get_by_name);
619 * dev_get_by_name_rcu - find a device by its name
620 * @net: the applicable net namespace
621 * @name: name to find
623 * Find an interface by name.
624 * If the name is found a pointer to the device is returned.
625 * If the name is not found then %NULL is returned.
626 * The reference counters are not incremented so the caller must be
627 * careful with locks. The caller must hold RCU lock.
630 struct net_device *dev_get_by_name_rcu(struct net *net, const char *name)
632 struct hlist_node *p;
633 struct net_device *dev;
634 struct hlist_head *head = dev_name_hash(net, name);
636 hlist_for_each_entry_rcu(dev, p, head, name_hlist)
637 if (!strncmp(dev->name, name, IFNAMSIZ))
642 EXPORT_SYMBOL(dev_get_by_name_rcu);
645 * dev_get_by_name - find a device by its name
646 * @net: the applicable net namespace
647 * @name: name to find
649 * Find an interface by name. This can be called from any
650 * context and does its own locking. The returned handle has
651 * the usage count incremented and the caller must use dev_put() to
652 * release it when it is no longer needed. %NULL is returned if no
653 * matching device is found.
656 struct net_device *dev_get_by_name(struct net *net, const char *name)
658 struct net_device *dev;
661 dev = dev_get_by_name_rcu(net, name);
667 EXPORT_SYMBOL(dev_get_by_name);
670 * __dev_get_by_index - find a device by its ifindex
671 * @net: the applicable net namespace
672 * @ifindex: index of device
674 * Search for an interface by index. Returns %NULL if the device
675 * is not found or a pointer to the device. The device has not
676 * had its reference counter increased so the caller must be careful
677 * about locking. The caller must hold either the RTNL semaphore
681 struct net_device *__dev_get_by_index(struct net *net, int ifindex)
683 struct hlist_node *p;
684 struct net_device *dev;
685 struct hlist_head *head = dev_index_hash(net, ifindex);
687 hlist_for_each_entry(dev, p, head, index_hlist)
688 if (dev->ifindex == ifindex)
693 EXPORT_SYMBOL(__dev_get_by_index);
696 * dev_get_by_index_rcu - find a device by its ifindex
697 * @net: the applicable net namespace
698 * @ifindex: index of device
700 * Search for an interface by index. Returns %NULL if the device
701 * is not found or a pointer to the device. The device has not
702 * had its reference counter increased so the caller must be careful
703 * about locking. The caller must hold RCU lock.
706 struct net_device *dev_get_by_index_rcu(struct net *net, int ifindex)
708 struct hlist_node *p;
709 struct net_device *dev;
710 struct hlist_head *head = dev_index_hash(net, ifindex);
712 hlist_for_each_entry_rcu(dev, p, head, index_hlist)
713 if (dev->ifindex == ifindex)
718 EXPORT_SYMBOL(dev_get_by_index_rcu);
722 * dev_get_by_index - find a device by its ifindex
723 * @net: the applicable net namespace
724 * @ifindex: index of device
726 * Search for an interface by index. Returns NULL if the device
727 * is not found or a pointer to the device. The device returned has
728 * had a reference added and the pointer is safe until the user calls
729 * dev_put to indicate they have finished with it.
732 struct net_device *dev_get_by_index(struct net *net, int ifindex)
734 struct net_device *dev;
737 dev = dev_get_by_index_rcu(net, ifindex);
743 EXPORT_SYMBOL(dev_get_by_index);
746 * dev_getbyhwaddr_rcu - find a device by its hardware address
747 * @net: the applicable net namespace
748 * @type: media type of device
749 * @ha: hardware address
751 * Search for an interface by MAC address. Returns NULL if the device
752 * is not found or a pointer to the device. The caller must hold RCU
753 * The returned device has not had its ref count increased
754 * and the caller must therefore be careful about locking
758 struct net_device *dev_getbyhwaddr_rcu(struct net *net, unsigned short type,
761 struct net_device *dev;
763 for_each_netdev_rcu(net, dev)
764 if (dev->type == type &&
765 !memcmp(dev->dev_addr, ha, dev->addr_len))
770 EXPORT_SYMBOL(dev_getbyhwaddr_rcu);
772 struct net_device *__dev_getfirstbyhwtype(struct net *net, unsigned short type)
774 struct net_device *dev;
777 for_each_netdev(net, dev)
778 if (dev->type == type)
783 EXPORT_SYMBOL(__dev_getfirstbyhwtype);
785 struct net_device *dev_getfirstbyhwtype(struct net *net, unsigned short type)
787 struct net_device *dev, *ret = NULL;
790 for_each_netdev_rcu(net, dev)
791 if (dev->type == type) {
799 EXPORT_SYMBOL(dev_getfirstbyhwtype);
802 * dev_get_by_flags_rcu - find any device with given flags
803 * @net: the applicable net namespace
804 * @if_flags: IFF_* values
805 * @mask: bitmask of bits in if_flags to check
807 * Search for any interface with the given flags. Returns NULL if a device
808 * is not found or a pointer to the device. Must be called inside
809 * rcu_read_lock(), and result refcount is unchanged.
812 struct net_device *dev_get_by_flags_rcu(struct net *net, unsigned short if_flags,
815 struct net_device *dev, *ret;
818 for_each_netdev_rcu(net, dev) {
819 if (((dev->flags ^ if_flags) & mask) == 0) {
826 EXPORT_SYMBOL(dev_get_by_flags_rcu);
829 * dev_valid_name - check if name is okay for network device
832 * Network device names need to be valid file names to
833 * to allow sysfs to work. We also disallow any kind of
836 int dev_valid_name(const char *name)
840 if (strlen(name) >= IFNAMSIZ)
842 if (!strcmp(name, ".") || !strcmp(name, ".."))
846 if (*name == '/' || isspace(*name))
852 EXPORT_SYMBOL(dev_valid_name);
855 * __dev_alloc_name - allocate a name for a device
856 * @net: network namespace to allocate the device name in
857 * @name: name format string
858 * @buf: scratch buffer and result name string
860 * Passed a format string - eg "lt%d" it will try and find a suitable
861 * id. It scans list of devices to build up a free map, then chooses
862 * the first empty slot. The caller must hold the dev_base or rtnl lock
863 * while allocating the name and adding the device in order to avoid
865 * Limited to bits_per_byte * page size devices (ie 32K on most platforms).
866 * Returns the number of the unit assigned or a negative errno code.
869 static int __dev_alloc_name(struct net *net, const char *name, char *buf)
873 const int max_netdevices = 8*PAGE_SIZE;
874 unsigned long *inuse;
875 struct net_device *d;
877 p = strnchr(name, IFNAMSIZ-1, '%');
880 * Verify the string as this thing may have come from
881 * the user. There must be either one "%d" and no other "%"
884 if (p[1] != 'd' || strchr(p + 2, '%'))
887 /* Use one page as a bit array of possible slots */
888 inuse = (unsigned long *) get_zeroed_page(GFP_ATOMIC);
892 for_each_netdev(net, d) {
893 if (!sscanf(d->name, name, &i))
895 if (i < 0 || i >= max_netdevices)
898 /* avoid cases where sscanf is not exact inverse of printf */
899 snprintf(buf, IFNAMSIZ, name, i);
900 if (!strncmp(buf, d->name, IFNAMSIZ))
904 i = find_first_zero_bit(inuse, max_netdevices);
905 free_page((unsigned long) inuse);
909 snprintf(buf, IFNAMSIZ, name, i);
910 if (!__dev_get_by_name(net, buf))
913 /* It is possible to run out of possible slots
914 * when the name is long and there isn't enough space left
915 * for the digits, or if all bits are used.
921 * dev_alloc_name - allocate a name for a device
923 * @name: name format string
925 * Passed a format string - eg "lt%d" it will try and find a suitable
926 * id. It scans list of devices to build up a free map, then chooses
927 * the first empty slot. The caller must hold the dev_base or rtnl lock
928 * while allocating the name and adding the device in order to avoid
930 * Limited to bits_per_byte * page size devices (ie 32K on most platforms).
931 * Returns the number of the unit assigned or a negative errno code.
934 int dev_alloc_name(struct net_device *dev, const char *name)
940 BUG_ON(!dev_net(dev));
942 ret = __dev_alloc_name(net, name, buf);
944 strlcpy(dev->name, buf, IFNAMSIZ);
947 EXPORT_SYMBOL(dev_alloc_name);
949 static int dev_get_valid_name(struct net_device *dev, const char *name, bool fmt)
953 BUG_ON(!dev_net(dev));
956 if (!dev_valid_name(name))
959 if (fmt && strchr(name, '%'))
960 return dev_alloc_name(dev, name);
961 else if (__dev_get_by_name(net, name))
963 else if (dev->name != name)
964 strlcpy(dev->name, name, IFNAMSIZ);
970 * dev_change_name - change name of a device
972 * @newname: name (or format string) must be at least IFNAMSIZ
974 * Change name of a device, can pass format strings "eth%d".
977 int dev_change_name(struct net_device *dev, const char *newname)
979 char oldname[IFNAMSIZ];
985 BUG_ON(!dev_net(dev));
988 if (dev->flags & IFF_UP)
991 if (strncmp(newname, dev->name, IFNAMSIZ) == 0)
994 memcpy(oldname, dev->name, IFNAMSIZ);
996 err = dev_get_valid_name(dev, newname, 1);
1001 ret = device_rename(&dev->dev, dev->name);
1003 memcpy(dev->name, oldname, IFNAMSIZ);
1007 write_lock_bh(&dev_base_lock);
1008 hlist_del(&dev->name_hlist);
1009 write_unlock_bh(&dev_base_lock);
1013 write_lock_bh(&dev_base_lock);
1014 hlist_add_head_rcu(&dev->name_hlist, dev_name_hash(net, dev->name));
1015 write_unlock_bh(&dev_base_lock);
1017 ret = call_netdevice_notifiers(NETDEV_CHANGENAME, dev);
1018 ret = notifier_to_errno(ret);
1021 /* err >= 0 after dev_alloc_name() or stores the first errno */
1024 memcpy(dev->name, oldname, IFNAMSIZ);
1028 "%s: name change rollback failed: %d.\n",
1037 * dev_set_alias - change ifalias of a device
1039 * @alias: name up to IFALIASZ
1040 * @len: limit of bytes to copy from info
1042 * Set ifalias for a device,
1044 int dev_set_alias(struct net_device *dev, const char *alias, size_t len)
1048 if (len >= IFALIASZ)
1053 kfree(dev->ifalias);
1054 dev->ifalias = NULL;
1059 dev->ifalias = krealloc(dev->ifalias, len + 1, GFP_KERNEL);
1063 strlcpy(dev->ifalias, alias, len+1);
1069 * netdev_features_change - device changes features
1070 * @dev: device to cause notification
1072 * Called to indicate a device has changed features.
1074 void netdev_features_change(struct net_device *dev)
1076 call_netdevice_notifiers(NETDEV_FEAT_CHANGE, dev);
1078 EXPORT_SYMBOL(netdev_features_change);
1081 * netdev_state_change - device changes state
1082 * @dev: device to cause notification
1084 * Called to indicate a device has changed state. This function calls
1085 * the notifier chains for netdev_chain and sends a NEWLINK message
1086 * to the routing socket.
1088 void netdev_state_change(struct net_device *dev)
1090 if (dev->flags & IFF_UP) {
1091 call_netdevice_notifiers(NETDEV_CHANGE, dev);
1092 rtmsg_ifinfo(RTM_NEWLINK, dev, 0);
1095 EXPORT_SYMBOL(netdev_state_change);
1097 int netdev_bonding_change(struct net_device *dev, unsigned long event)
1099 return call_netdevice_notifiers(event, dev);
1101 EXPORT_SYMBOL(netdev_bonding_change);
1104 * dev_load - load a network module
1105 * @net: the applicable net namespace
1106 * @name: name of interface
1108 * If a network interface is not present and the process has suitable
1109 * privileges this function loads the module. If module loading is not
1110 * available in this kernel then it becomes a nop.
1113 void dev_load(struct net *net, const char *name)
1115 struct net_device *dev;
1118 dev = dev_get_by_name_rcu(net, name);
1121 if (!dev && capable(CAP_NET_ADMIN))
1122 request_module("%s", name);
1124 EXPORT_SYMBOL(dev_load);
1126 static int __dev_open(struct net_device *dev)
1128 const struct net_device_ops *ops = dev->netdev_ops;
1134 * Is it even present?
1136 if (!netif_device_present(dev))
1139 ret = call_netdevice_notifiers(NETDEV_PRE_UP, dev);
1140 ret = notifier_to_errno(ret);
1145 * Call device private open method
1147 set_bit(__LINK_STATE_START, &dev->state);
1149 if (ops->ndo_validate_addr)
1150 ret = ops->ndo_validate_addr(dev);
1152 if (!ret && ops->ndo_open)
1153 ret = ops->ndo_open(dev);
1156 * If it went open OK then:
1160 clear_bit(__LINK_STATE_START, &dev->state);
1165 dev->flags |= IFF_UP;
1170 net_dmaengine_get();
1173 * Initialize multicasting status
1175 dev_set_rx_mode(dev);
1178 * Wakeup transmit queue engine
1187 * dev_open - prepare an interface for use.
1188 * @dev: device to open
1190 * Takes a device from down to up state. The device's private open
1191 * function is invoked and then the multicast lists are loaded. Finally
1192 * the device is moved into the up state and a %NETDEV_UP message is
1193 * sent to the netdev notifier chain.
1195 * Calling this function on an active interface is a nop. On a failure
1196 * a negative errno code is returned.
1198 int dev_open(struct net_device *dev)
1205 if (dev->flags & IFF_UP)
1211 ret = __dev_open(dev);
1216 * ... and announce new interface.
1218 rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP|IFF_RUNNING);
1219 call_netdevice_notifiers(NETDEV_UP, dev);
1223 EXPORT_SYMBOL(dev_open);
1225 static int __dev_close_many(struct list_head *head)
1227 struct net_device *dev;
1232 list_for_each_entry(dev, head, unreg_list) {
1234 * Tell people we are going down, so that they can
1235 * prepare to death, when device is still operating.
1237 call_netdevice_notifiers(NETDEV_GOING_DOWN, dev);
1239 clear_bit(__LINK_STATE_START, &dev->state);
1241 /* Synchronize to scheduled poll. We cannot touch poll list, it
1242 * can be even on different cpu. So just clear netif_running().
1244 * dev->stop() will invoke napi_disable() on all of it's
1245 * napi_struct instances on this device.
1247 smp_mb__after_clear_bit(); /* Commit netif_running(). */
1250 dev_deactivate_many(head);
1252 list_for_each_entry(dev, head, unreg_list) {
1253 const struct net_device_ops *ops = dev->netdev_ops;
1256 * Call the device specific close. This cannot fail.
1257 * Only if device is UP
1259 * We allow it to be called even after a DETACH hot-plug
1266 * Device is now down.
1269 dev->flags &= ~IFF_UP;
1274 net_dmaengine_put();
1280 static int __dev_close(struct net_device *dev)
1284 list_add(&dev->unreg_list, &single);
1285 return __dev_close_many(&single);
1288 int dev_close_many(struct list_head *head)
1290 struct net_device *dev, *tmp;
1291 LIST_HEAD(tmp_list);
1293 list_for_each_entry_safe(dev, tmp, head, unreg_list)
1294 if (!(dev->flags & IFF_UP))
1295 list_move(&dev->unreg_list, &tmp_list);
1297 __dev_close_many(head);
1300 * Tell people we are down
1302 list_for_each_entry(dev, head, unreg_list) {
1303 rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP|IFF_RUNNING);
1304 call_netdevice_notifiers(NETDEV_DOWN, dev);
1307 /* rollback_registered_many needs the complete original list */
1308 list_splice(&tmp_list, head);
1313 * dev_close - shutdown an interface.
1314 * @dev: device to shutdown
1316 * This function moves an active device into down state. A
1317 * %NETDEV_GOING_DOWN is sent to the netdev notifier chain. The device
1318 * is then deactivated and finally a %NETDEV_DOWN is sent to the notifier
1321 int dev_close(struct net_device *dev)
1325 list_add(&dev->unreg_list, &single);
1326 dev_close_many(&single);
1330 EXPORT_SYMBOL(dev_close);
1334 * dev_disable_lro - disable Large Receive Offload on a device
1337 * Disable Large Receive Offload (LRO) on a net device. Must be
1338 * called under RTNL. This is needed if received packets may be
1339 * forwarded to another interface.
1341 void dev_disable_lro(struct net_device *dev)
1343 if (dev->ethtool_ops && dev->ethtool_ops->get_flags &&
1344 dev->ethtool_ops->set_flags) {
1345 u32 flags = dev->ethtool_ops->get_flags(dev);
1346 if (flags & ETH_FLAG_LRO) {
1347 flags &= ~ETH_FLAG_LRO;
1348 dev->ethtool_ops->set_flags(dev, flags);
1351 WARN_ON(dev->features & NETIF_F_LRO);
1353 EXPORT_SYMBOL(dev_disable_lro);
1356 static int dev_boot_phase = 1;
1359 * Device change register/unregister. These are not inline or static
1360 * as we export them to the world.
1364 * register_netdevice_notifier - register a network notifier block
1367 * Register a notifier to be called when network device events occur.
1368 * The notifier passed is linked into the kernel structures and must
1369 * not be reused until it has been unregistered. A negative errno code
1370 * is returned on a failure.
1372 * When registered all registration and up events are replayed
1373 * to the new notifier to allow device to have a race free
1374 * view of the network device list.
1377 int register_netdevice_notifier(struct notifier_block *nb)
1379 struct net_device *dev;
1380 struct net_device *last;
1385 err = raw_notifier_chain_register(&netdev_chain, nb);
1391 for_each_netdev(net, dev) {
1392 err = nb->notifier_call(nb, NETDEV_REGISTER, dev);
1393 err = notifier_to_errno(err);
1397 if (!(dev->flags & IFF_UP))
1400 nb->notifier_call(nb, NETDEV_UP, dev);
1411 for_each_netdev(net, dev) {
1415 if (dev->flags & IFF_UP) {
1416 nb->notifier_call(nb, NETDEV_GOING_DOWN, dev);
1417 nb->notifier_call(nb, NETDEV_DOWN, dev);
1419 nb->notifier_call(nb, NETDEV_UNREGISTER, dev);
1420 nb->notifier_call(nb, NETDEV_UNREGISTER_BATCH, dev);
1424 raw_notifier_chain_unregister(&netdev_chain, nb);
1427 EXPORT_SYMBOL(register_netdevice_notifier);
1430 * unregister_netdevice_notifier - unregister a network notifier block
1433 * Unregister a notifier previously registered by
1434 * register_netdevice_notifier(). The notifier is unlinked into the
1435 * kernel structures and may then be reused. A negative errno code
1436 * is returned on a failure.
1439 int unregister_netdevice_notifier(struct notifier_block *nb)
1444 err = raw_notifier_chain_unregister(&netdev_chain, nb);
1448 EXPORT_SYMBOL(unregister_netdevice_notifier);
1451 * call_netdevice_notifiers - call all network notifier blocks
1452 * @val: value passed unmodified to notifier function
1453 * @dev: net_device pointer passed unmodified to notifier function
1455 * Call all network notifier blocks. Parameters and return value
1456 * are as for raw_notifier_call_chain().
1459 int call_netdevice_notifiers(unsigned long val, struct net_device *dev)
1462 return raw_notifier_call_chain(&netdev_chain, val, dev);
1465 /* When > 0 there are consumers of rx skb time stamps */
1466 static atomic_t netstamp_needed = ATOMIC_INIT(0);
1468 void net_enable_timestamp(void)
1470 atomic_inc(&netstamp_needed);
1472 EXPORT_SYMBOL(net_enable_timestamp);
1474 void net_disable_timestamp(void)
1476 atomic_dec(&netstamp_needed);
1478 EXPORT_SYMBOL(net_disable_timestamp);
1480 static inline void net_timestamp_set(struct sk_buff *skb)
1482 if (atomic_read(&netstamp_needed))
1483 __net_timestamp(skb);
1485 skb->tstamp.tv64 = 0;
1488 static inline void net_timestamp_check(struct sk_buff *skb)
1490 if (!skb->tstamp.tv64 && atomic_read(&netstamp_needed))
1491 __net_timestamp(skb);
1495 * dev_forward_skb - loopback an skb to another netif
1497 * @dev: destination network device
1498 * @skb: buffer to forward
1501 * NET_RX_SUCCESS (no congestion)
1502 * NET_RX_DROP (packet was dropped, but freed)
1504 * dev_forward_skb can be used for injecting an skb from the
1505 * start_xmit function of one device into the receive queue
1506 * of another device.
1508 * The receiving device may be in another namespace, so
1509 * we have to clear all information in the skb that could
1510 * impact namespace isolation.
1512 int dev_forward_skb(struct net_device *dev, struct sk_buff *skb)
1517 if (unlikely(!(dev->flags & IFF_UP) ||
1518 (skb->len > (dev->mtu + dev->hard_header_len + VLAN_HLEN)))) {
1519 atomic_long_inc(&dev->rx_dropped);
1523 skb_set_dev(skb, dev);
1524 skb->tstamp.tv64 = 0;
1525 skb->pkt_type = PACKET_HOST;
1526 skb->protocol = eth_type_trans(skb, dev);
1527 return netif_rx(skb);
1529 EXPORT_SYMBOL_GPL(dev_forward_skb);
1531 static inline int deliver_skb(struct sk_buff *skb,
1532 struct packet_type *pt_prev,
1533 struct net_device *orig_dev)
1535 atomic_inc(&skb->users);
1536 return pt_prev->func(skb, skb->dev, pt_prev, orig_dev);
1540 * Support routine. Sends outgoing frames to any network
1541 * taps currently in use.
1544 static void dev_queue_xmit_nit(struct sk_buff *skb, struct net_device *dev)
1546 struct packet_type *ptype;
1547 struct sk_buff *skb2 = NULL;
1548 struct packet_type *pt_prev = NULL;
1551 list_for_each_entry_rcu(ptype, &ptype_all, list) {
1552 /* Never send packets back to the socket
1553 * they originated from - MvS (miquels@drinkel.ow.org)
1555 if ((ptype->dev == dev || !ptype->dev) &&
1556 (ptype->af_packet_priv == NULL ||
1557 (struct sock *)ptype->af_packet_priv != skb->sk)) {
1559 deliver_skb(skb2, pt_prev, skb->dev);
1564 skb2 = skb_clone(skb, GFP_ATOMIC);
1568 net_timestamp_set(skb2);
1570 /* skb->nh should be correctly
1571 set by sender, so that the second statement is
1572 just protection against buggy protocols.
1574 skb_reset_mac_header(skb2);
1576 if (skb_network_header(skb2) < skb2->data ||
1577 skb2->network_header > skb2->tail) {
1578 if (net_ratelimit())
1579 printk(KERN_CRIT "protocol %04x is "
1581 ntohs(skb2->protocol),
1583 skb_reset_network_header(skb2);
1586 skb2->transport_header = skb2->network_header;
1587 skb2->pkt_type = PACKET_OUTGOING;
1592 pt_prev->func(skb2, skb->dev, pt_prev, skb->dev);
1597 * Routine to help set real_num_tx_queues. To avoid skbs mapped to queues
1598 * greater then real_num_tx_queues stale skbs on the qdisc must be flushed.
1600 int netif_set_real_num_tx_queues(struct net_device *dev, unsigned int txq)
1604 if (txq < 1 || txq > dev->num_tx_queues)
1607 if (dev->reg_state == NETREG_REGISTERED) {
1610 rc = netdev_queue_update_kobjects(dev, dev->real_num_tx_queues,
1615 if (txq < dev->real_num_tx_queues)
1616 qdisc_reset_all_tx_gt(dev, txq);
1619 dev->real_num_tx_queues = txq;
1622 EXPORT_SYMBOL(netif_set_real_num_tx_queues);
1626 * netif_set_real_num_rx_queues - set actual number of RX queues used
1627 * @dev: Network device
1628 * @rxq: Actual number of RX queues
1630 * This must be called either with the rtnl_lock held or before
1631 * registration of the net device. Returns 0 on success, or a
1632 * negative error code. If called before registration, it always
1635 int netif_set_real_num_rx_queues(struct net_device *dev, unsigned int rxq)
1639 if (rxq < 1 || rxq > dev->num_rx_queues)
1642 if (dev->reg_state == NETREG_REGISTERED) {
1645 rc = net_rx_queue_update_kobjects(dev, dev->real_num_rx_queues,
1651 dev->real_num_rx_queues = rxq;
1654 EXPORT_SYMBOL(netif_set_real_num_rx_queues);
1657 static inline void __netif_reschedule(struct Qdisc *q)
1659 struct softnet_data *sd;
1660 unsigned long flags;
1662 local_irq_save(flags);
1663 sd = &__get_cpu_var(softnet_data);
1664 q->next_sched = NULL;
1665 *sd->output_queue_tailp = q;
1666 sd->output_queue_tailp = &q->next_sched;
1667 raise_softirq_irqoff(NET_TX_SOFTIRQ);
1668 local_irq_restore(flags);
1671 void __netif_schedule(struct Qdisc *q)
1673 if (!test_and_set_bit(__QDISC_STATE_SCHED, &q->state))
1674 __netif_reschedule(q);
1676 EXPORT_SYMBOL(__netif_schedule);
1678 void dev_kfree_skb_irq(struct sk_buff *skb)
1680 if (atomic_dec_and_test(&skb->users)) {
1681 struct softnet_data *sd;
1682 unsigned long flags;
1684 local_irq_save(flags);
1685 sd = &__get_cpu_var(softnet_data);
1686 skb->next = sd->completion_queue;
1687 sd->completion_queue = skb;
1688 raise_softirq_irqoff(NET_TX_SOFTIRQ);
1689 local_irq_restore(flags);
1692 EXPORT_SYMBOL(dev_kfree_skb_irq);
1694 void dev_kfree_skb_any(struct sk_buff *skb)
1696 if (in_irq() || irqs_disabled())
1697 dev_kfree_skb_irq(skb);
1701 EXPORT_SYMBOL(dev_kfree_skb_any);
1705 * netif_device_detach - mark device as removed
1706 * @dev: network device
1708 * Mark device as removed from system and therefore no longer available.
1710 void netif_device_detach(struct net_device *dev)
1712 if (test_and_clear_bit(__LINK_STATE_PRESENT, &dev->state) &&
1713 netif_running(dev)) {
1714 netif_tx_stop_all_queues(dev);
1717 EXPORT_SYMBOL(netif_device_detach);
1720 * netif_device_attach - mark device as attached
1721 * @dev: network device
1723 * Mark device as attached from system and restart if needed.
1725 void netif_device_attach(struct net_device *dev)
1727 if (!test_and_set_bit(__LINK_STATE_PRESENT, &dev->state) &&
1728 netif_running(dev)) {
1729 netif_tx_wake_all_queues(dev);
1730 __netdev_watchdog_up(dev);
1733 EXPORT_SYMBOL(netif_device_attach);
1735 static bool can_checksum_protocol(unsigned long features, __be16 protocol)
1737 return ((features & NETIF_F_GEN_CSUM) ||
1738 ((features & NETIF_F_V4_CSUM) &&
1739 protocol == htons(ETH_P_IP)) ||
1740 ((features & NETIF_F_V6_CSUM) &&
1741 protocol == htons(ETH_P_IPV6)) ||
1742 ((features & NETIF_F_FCOE_CRC) &&
1743 protocol == htons(ETH_P_FCOE)));
1746 static bool dev_can_checksum(struct net_device *dev, struct sk_buff *skb)
1748 __be16 protocol = skb->protocol;
1749 int features = dev->features;
1751 if (vlan_tx_tag_present(skb)) {
1752 features &= dev->vlan_features;
1753 } else if (protocol == htons(ETH_P_8021Q)) {
1754 struct vlan_ethhdr *veh = (struct vlan_ethhdr *)skb->data;
1755 protocol = veh->h_vlan_encapsulated_proto;
1756 features &= dev->vlan_features;
1759 return can_checksum_protocol(features, protocol);
1763 * skb_dev_set -- assign a new device to a buffer
1764 * @skb: buffer for the new device
1765 * @dev: network device
1767 * If an skb is owned by a device already, we have to reset
1768 * all data private to the namespace a device belongs to
1769 * before assigning it a new device.
1771 #ifdef CONFIG_NET_NS
1772 void skb_set_dev(struct sk_buff *skb, struct net_device *dev)
1775 if (skb->dev && !net_eq(dev_net(skb->dev), dev_net(dev))) {
1778 skb_init_secmark(skb);
1782 skb->ipvs_property = 0;
1783 #ifdef CONFIG_NET_SCHED
1789 EXPORT_SYMBOL(skb_set_dev);
1790 #endif /* CONFIG_NET_NS */
1793 * Invalidate hardware checksum when packet is to be mangled, and
1794 * complete checksum manually on outgoing path.
1796 int skb_checksum_help(struct sk_buff *skb)
1799 int ret = 0, offset;
1801 if (skb->ip_summed == CHECKSUM_COMPLETE)
1802 goto out_set_summed;
1804 if (unlikely(skb_shinfo(skb)->gso_size)) {
1805 /* Let GSO fix up the checksum. */
1806 goto out_set_summed;
1809 offset = skb_checksum_start_offset(skb);
1810 BUG_ON(offset >= skb_headlen(skb));
1811 csum = skb_checksum(skb, offset, skb->len - offset, 0);
1813 offset += skb->csum_offset;
1814 BUG_ON(offset + sizeof(__sum16) > skb_headlen(skb));
1816 if (skb_cloned(skb) &&
1817 !skb_clone_writable(skb, offset + sizeof(__sum16))) {
1818 ret = pskb_expand_head(skb, 0, 0, GFP_ATOMIC);
1823 *(__sum16 *)(skb->data + offset) = csum_fold(csum);
1825 skb->ip_summed = CHECKSUM_NONE;
1829 EXPORT_SYMBOL(skb_checksum_help);
1832 * skb_gso_segment - Perform segmentation on skb.
1833 * @skb: buffer to segment
1834 * @features: features for the output path (see dev->features)
1836 * This function segments the given skb and returns a list of segments.
1838 * It may return NULL if the skb requires no segmentation. This is
1839 * only possible when GSO is used for verifying header integrity.
1841 struct sk_buff *skb_gso_segment(struct sk_buff *skb, int features)
1843 struct sk_buff *segs = ERR_PTR(-EPROTONOSUPPORT);
1844 struct packet_type *ptype;
1845 __be16 type = skb->protocol;
1846 int vlan_depth = ETH_HLEN;
1849 while (type == htons(ETH_P_8021Q)) {
1850 struct vlan_hdr *vh;
1852 if (unlikely(!pskb_may_pull(skb, vlan_depth + VLAN_HLEN)))
1853 return ERR_PTR(-EINVAL);
1855 vh = (struct vlan_hdr *)(skb->data + vlan_depth);
1856 type = vh->h_vlan_encapsulated_proto;
1857 vlan_depth += VLAN_HLEN;
1860 skb_reset_mac_header(skb);
1861 skb->mac_len = skb->network_header - skb->mac_header;
1862 __skb_pull(skb, skb->mac_len);
1864 if (unlikely(skb->ip_summed != CHECKSUM_PARTIAL)) {
1865 struct net_device *dev = skb->dev;
1866 struct ethtool_drvinfo info = {};
1868 if (dev && dev->ethtool_ops && dev->ethtool_ops->get_drvinfo)
1869 dev->ethtool_ops->get_drvinfo(dev, &info);
1871 WARN(1, "%s: caps=(0x%lx, 0x%lx) len=%d data_len=%d ip_summed=%d\n",
1872 info.driver, dev ? dev->features : 0L,
1873 skb->sk ? skb->sk->sk_route_caps : 0L,
1874 skb->len, skb->data_len, skb->ip_summed);
1876 if (skb_header_cloned(skb) &&
1877 (err = pskb_expand_head(skb, 0, 0, GFP_ATOMIC)))
1878 return ERR_PTR(err);
1882 list_for_each_entry_rcu(ptype,
1883 &ptype_base[ntohs(type) & PTYPE_HASH_MASK], list) {
1884 if (ptype->type == type && !ptype->dev && ptype->gso_segment) {
1885 if (unlikely(skb->ip_summed != CHECKSUM_PARTIAL)) {
1886 err = ptype->gso_send_check(skb);
1887 segs = ERR_PTR(err);
1888 if (err || skb_gso_ok(skb, features))
1890 __skb_push(skb, (skb->data -
1891 skb_network_header(skb)));
1893 segs = ptype->gso_segment(skb, features);
1899 __skb_push(skb, skb->data - skb_mac_header(skb));
1903 EXPORT_SYMBOL(skb_gso_segment);
1905 /* Take action when hardware reception checksum errors are detected. */
1907 void netdev_rx_csum_fault(struct net_device *dev)
1909 if (net_ratelimit()) {
1910 printk(KERN_ERR "%s: hw csum failure.\n",
1911 dev ? dev->name : "<unknown>");
1915 EXPORT_SYMBOL(netdev_rx_csum_fault);
1918 /* Actually, we should eliminate this check as soon as we know, that:
1919 * 1. IOMMU is present and allows to map all the memory.
1920 * 2. No high memory really exists on this machine.
1923 static int illegal_highdma(struct net_device *dev, struct sk_buff *skb)
1925 #ifdef CONFIG_HIGHMEM
1927 if (!(dev->features & NETIF_F_HIGHDMA)) {
1928 for (i = 0; i < skb_shinfo(skb)->nr_frags; i++)
1929 if (PageHighMem(skb_shinfo(skb)->frags[i].page))
1933 if (PCI_DMA_BUS_IS_PHYS) {
1934 struct device *pdev = dev->dev.parent;
1938 for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
1939 dma_addr_t addr = page_to_phys(skb_shinfo(skb)->frags[i].page);
1940 if (!pdev->dma_mask || addr + PAGE_SIZE - 1 > *pdev->dma_mask)
1949 void (*destructor)(struct sk_buff *skb);
1952 #define DEV_GSO_CB(skb) ((struct dev_gso_cb *)(skb)->cb)
1954 static void dev_gso_skb_destructor(struct sk_buff *skb)
1956 struct dev_gso_cb *cb;
1959 struct sk_buff *nskb = skb->next;
1961 skb->next = nskb->next;
1964 } while (skb->next);
1966 cb = DEV_GSO_CB(skb);
1968 cb->destructor(skb);
1972 * dev_gso_segment - Perform emulated hardware segmentation on skb.
1973 * @skb: buffer to segment
1975 * This function segments the given skb and stores the list of segments
1978 static int dev_gso_segment(struct sk_buff *skb)
1980 struct net_device *dev = skb->dev;
1981 struct sk_buff *segs;
1982 int features = dev->features & ~(illegal_highdma(dev, skb) ?
1985 segs = skb_gso_segment(skb, features);
1987 /* Verifying header integrity only. */
1992 return PTR_ERR(segs);
1995 DEV_GSO_CB(skb)->destructor = skb->destructor;
1996 skb->destructor = dev_gso_skb_destructor;
2002 * Try to orphan skb early, right before transmission by the device.
2003 * We cannot orphan skb if tx timestamp is requested or the sk-reference
2004 * is needed on driver level for other reasons, e.g. see net/can/raw.c
2006 static inline void skb_orphan_try(struct sk_buff *skb)
2008 struct sock *sk = skb->sk;
2010 if (sk && !skb_shinfo(skb)->tx_flags) {
2011 /* skb_tx_hash() wont be able to get sk.
2012 * We copy sk_hash into skb->rxhash
2015 skb->rxhash = sk->sk_hash;
2020 static int harmonize_features(struct sk_buff *skb, __be16 protocol, int features)
2022 if (!can_checksum_protocol(protocol, features)) {
2023 features &= ~NETIF_F_ALL_CSUM;
2024 features &= ~NETIF_F_SG;
2025 } else if (illegal_highdma(skb->dev, skb)) {
2026 features &= ~NETIF_F_SG;
2032 int netif_skb_features(struct sk_buff *skb)
2034 __be16 protocol = skb->protocol;
2035 int features = skb->dev->features;
2037 if (protocol == htons(ETH_P_8021Q)) {
2038 struct vlan_ethhdr *veh = (struct vlan_ethhdr *)skb->data;
2039 protocol = veh->h_vlan_encapsulated_proto;
2040 } else if (!vlan_tx_tag_present(skb)) {
2041 return harmonize_features(skb, protocol, features);
2044 features &= skb->dev->vlan_features;
2046 if (protocol != htons(ETH_P_8021Q)) {
2047 return harmonize_features(skb, protocol, features);
2049 features &= NETIF_F_SG | NETIF_F_HIGHDMA | NETIF_F_FRAGLIST |
2051 return harmonize_features(skb, protocol, features);
2054 EXPORT_SYMBOL(netif_skb_features);
2057 * Returns true if either:
2058 * 1. skb has frag_list and the device doesn't support FRAGLIST, or
2059 * 2. skb is fragmented and the device does not support SG, or if
2060 * at least one of fragments is in highmem and device does not
2061 * support DMA from it.
2063 static inline int skb_needs_linearize(struct sk_buff *skb,
2064 struct net_device *dev)
2066 if (skb_is_nonlinear(skb)) {
2067 int features = dev->features;
2069 if (vlan_tx_tag_present(skb))
2070 features &= dev->vlan_features;
2072 return (skb_has_frag_list(skb) &&
2073 !(features & NETIF_F_FRAGLIST)) ||
2074 (skb_shinfo(skb)->nr_frags &&
2075 (!(features & NETIF_F_SG) ||
2076 illegal_highdma(dev, skb)));
2082 int dev_hard_start_xmit(struct sk_buff *skb, struct net_device *dev,
2083 struct netdev_queue *txq)
2085 const struct net_device_ops *ops = dev->netdev_ops;
2086 int rc = NETDEV_TX_OK;
2088 if (likely(!skb->next)) {
2090 * If device doesnt need skb->dst, release it right now while
2091 * its hot in this cpu cache
2093 if (dev->priv_flags & IFF_XMIT_DST_RELEASE)
2096 if (!list_empty(&ptype_all))
2097 dev_queue_xmit_nit(skb, dev);
2099 skb_orphan_try(skb);
2101 if (vlan_tx_tag_present(skb) &&
2102 !(dev->features & NETIF_F_HW_VLAN_TX)) {
2103 skb = __vlan_put_tag(skb, vlan_tx_tag_get(skb));
2110 if (netif_needs_gso(dev, skb)) {
2111 if (unlikely(dev_gso_segment(skb)))
2116 if (skb_needs_linearize(skb, dev) &&
2117 __skb_linearize(skb))
2120 /* If packet is not checksummed and device does not
2121 * support checksumming for this protocol, complete
2122 * checksumming here.
2124 if (skb->ip_summed == CHECKSUM_PARTIAL) {
2125 skb_set_transport_header(skb,
2126 skb_checksum_start_offset(skb));
2127 if (!dev_can_checksum(dev, skb) &&
2128 skb_checksum_help(skb))
2133 rc = ops->ndo_start_xmit(skb, dev);
2134 trace_net_dev_xmit(skb, rc);
2135 if (rc == NETDEV_TX_OK)
2136 txq_trans_update(txq);
2142 struct sk_buff *nskb = skb->next;
2144 skb->next = nskb->next;
2148 * If device doesnt need nskb->dst, release it right now while
2149 * its hot in this cpu cache
2151 if (dev->priv_flags & IFF_XMIT_DST_RELEASE)
2154 rc = ops->ndo_start_xmit(nskb, dev);
2155 trace_net_dev_xmit(nskb, rc);
2156 if (unlikely(rc != NETDEV_TX_OK)) {
2157 if (rc & ~NETDEV_TX_MASK)
2158 goto out_kfree_gso_skb;
2159 nskb->next = skb->next;
2163 txq_trans_update(txq);
2164 if (unlikely(netif_tx_queue_stopped(txq) && skb->next))
2165 return NETDEV_TX_BUSY;
2166 } while (skb->next);
2169 if (likely(skb->next == NULL))
2170 skb->destructor = DEV_GSO_CB(skb)->destructor;
2177 static u32 hashrnd __read_mostly;
2180 * Returns a Tx hash based on the given packet descriptor a Tx queues' number
2181 * to be used as a distribution range.
2183 u16 __skb_tx_hash(const struct net_device *dev, const struct sk_buff *skb,
2184 unsigned int num_tx_queues)
2188 if (skb_rx_queue_recorded(skb)) {
2189 hash = skb_get_rx_queue(skb);
2190 while (unlikely(hash >= num_tx_queues))
2191 hash -= num_tx_queues;
2195 if (skb->sk && skb->sk->sk_hash)
2196 hash = skb->sk->sk_hash;
2198 hash = (__force u16) skb->protocol ^ skb->rxhash;
2199 hash = jhash_1word(hash, hashrnd);
2201 return (u16) (((u64) hash * num_tx_queues) >> 32);
2203 EXPORT_SYMBOL(__skb_tx_hash);
2205 static inline u16 dev_cap_txqueue(struct net_device *dev, u16 queue_index)
2207 if (unlikely(queue_index >= dev->real_num_tx_queues)) {
2208 if (net_ratelimit()) {
2209 pr_warning("%s selects TX queue %d, but "
2210 "real number of TX queues is %d\n",
2211 dev->name, queue_index, dev->real_num_tx_queues);
2218 static inline int get_xps_queue(struct net_device *dev, struct sk_buff *skb)
2221 struct xps_dev_maps *dev_maps;
2222 struct xps_map *map;
2223 int queue_index = -1;
2226 dev_maps = rcu_dereference(dev->xps_maps);
2228 map = rcu_dereference(
2229 dev_maps->cpu_map[raw_smp_processor_id()]);
2232 queue_index = map->queues[0];
2235 if (skb->sk && skb->sk->sk_hash)
2236 hash = skb->sk->sk_hash;
2238 hash = (__force u16) skb->protocol ^
2240 hash = jhash_1word(hash, hashrnd);
2241 queue_index = map->queues[
2242 ((u64)hash * map->len) >> 32];
2244 if (unlikely(queue_index >= dev->real_num_tx_queues))
2256 static struct netdev_queue *dev_pick_tx(struct net_device *dev,
2257 struct sk_buff *skb)
2260 const struct net_device_ops *ops = dev->netdev_ops;
2262 if (dev->real_num_tx_queues == 1)
2264 else if (ops->ndo_select_queue) {
2265 queue_index = ops->ndo_select_queue(dev, skb);
2266 queue_index = dev_cap_txqueue(dev, queue_index);
2268 struct sock *sk = skb->sk;
2269 queue_index = sk_tx_queue_get(sk);
2271 if (queue_index < 0 || skb->ooo_okay ||
2272 queue_index >= dev->real_num_tx_queues) {
2273 int old_index = queue_index;
2275 queue_index = get_xps_queue(dev, skb);
2276 if (queue_index < 0)
2277 queue_index = skb_tx_hash(dev, skb);
2279 if (queue_index != old_index && sk) {
2280 struct dst_entry *dst =
2281 rcu_dereference_check(sk->sk_dst_cache, 1);
2283 if (dst && skb_dst(skb) == dst)
2284 sk_tx_queue_set(sk, queue_index);
2289 skb_set_queue_mapping(skb, queue_index);
2290 return netdev_get_tx_queue(dev, queue_index);
2293 static inline int __dev_xmit_skb(struct sk_buff *skb, struct Qdisc *q,
2294 struct net_device *dev,
2295 struct netdev_queue *txq)
2297 spinlock_t *root_lock = qdisc_lock(q);
2298 bool contended = qdisc_is_running(q);
2302 * Heuristic to force contended enqueues to serialize on a
2303 * separate lock before trying to get qdisc main lock.
2304 * This permits __QDISC_STATE_RUNNING owner to get the lock more often
2305 * and dequeue packets faster.
2307 if (unlikely(contended))
2308 spin_lock(&q->busylock);
2310 spin_lock(root_lock);
2311 if (unlikely(test_bit(__QDISC_STATE_DEACTIVATED, &q->state))) {
2314 } else if ((q->flags & TCQ_F_CAN_BYPASS) && !qdisc_qlen(q) &&
2315 qdisc_run_begin(q)) {
2317 * This is a work-conserving queue; there are no old skbs
2318 * waiting to be sent out; and the qdisc is not running -
2319 * xmit the skb directly.
2321 if (!(dev->priv_flags & IFF_XMIT_DST_RELEASE))
2323 __qdisc_update_bstats(q, skb->len);
2324 if (sch_direct_xmit(skb, q, dev, txq, root_lock)) {
2325 if (unlikely(contended)) {
2326 spin_unlock(&q->busylock);
2333 rc = NET_XMIT_SUCCESS;
2336 rc = qdisc_enqueue_root(skb, q);
2337 if (qdisc_run_begin(q)) {
2338 if (unlikely(contended)) {
2339 spin_unlock(&q->busylock);
2345 spin_unlock(root_lock);
2346 if (unlikely(contended))
2347 spin_unlock(&q->busylock);
2351 static DEFINE_PER_CPU(int, xmit_recursion);
2352 #define RECURSION_LIMIT 10
2355 * dev_queue_xmit - transmit a buffer
2356 * @skb: buffer to transmit
2358 * Queue a buffer for transmission to a network device. The caller must
2359 * have set the device and priority and built the buffer before calling
2360 * this function. The function can be called from an interrupt.
2362 * A negative errno code is returned on a failure. A success does not
2363 * guarantee the frame will be transmitted as it may be dropped due
2364 * to congestion or traffic shaping.
2366 * -----------------------------------------------------------------------------------
2367 * I notice this method can also return errors from the queue disciplines,
2368 * including NET_XMIT_DROP, which is a positive value. So, errors can also
2371 * Regardless of the return value, the skb is consumed, so it is currently
2372 * difficult to retry a send to this method. (You can bump the ref count
2373 * before sending to hold a reference for retry if you are careful.)
2375 * When calling this method, interrupts MUST be enabled. This is because
2376 * the BH enable code must have IRQs enabled so that it will not deadlock.
2379 int dev_queue_xmit(struct sk_buff *skb)
2381 struct net_device *dev = skb->dev;
2382 struct netdev_queue *txq;
2386 /* Disable soft irqs for various locks below. Also
2387 * stops preemption for RCU.
2391 txq = dev_pick_tx(dev, skb);
2392 q = rcu_dereference_bh(txq->qdisc);
2394 #ifdef CONFIG_NET_CLS_ACT
2395 skb->tc_verd = SET_TC_AT(skb->tc_verd, AT_EGRESS);
2397 trace_net_dev_queue(skb);
2399 rc = __dev_xmit_skb(skb, q, dev, txq);
2403 /* The device has no queue. Common case for software devices:
2404 loopback, all the sorts of tunnels...
2406 Really, it is unlikely that netif_tx_lock protection is necessary
2407 here. (f.e. loopback and IP tunnels are clean ignoring statistics
2409 However, it is possible, that they rely on protection
2412 Check this and shot the lock. It is not prone from deadlocks.
2413 Either shot noqueue qdisc, it is even simpler 8)
2415 if (dev->flags & IFF_UP) {
2416 int cpu = smp_processor_id(); /* ok because BHs are off */
2418 if (txq->xmit_lock_owner != cpu) {
2420 if (__this_cpu_read(xmit_recursion) > RECURSION_LIMIT)
2421 goto recursion_alert;
2423 HARD_TX_LOCK(dev, txq, cpu);
2425 if (!netif_tx_queue_stopped(txq)) {
2426 __this_cpu_inc(xmit_recursion);
2427 rc = dev_hard_start_xmit(skb, dev, txq);
2428 __this_cpu_dec(xmit_recursion);
2429 if (dev_xmit_complete(rc)) {
2430 HARD_TX_UNLOCK(dev, txq);
2434 HARD_TX_UNLOCK(dev, txq);
2435 if (net_ratelimit())
2436 printk(KERN_CRIT "Virtual device %s asks to "
2437 "queue packet!\n", dev->name);
2439 /* Recursion is detected! It is possible,
2443 if (net_ratelimit())
2444 printk(KERN_CRIT "Dead loop on virtual device "
2445 "%s, fix it urgently!\n", dev->name);
2450 rcu_read_unlock_bh();
2455 rcu_read_unlock_bh();
2458 EXPORT_SYMBOL(dev_queue_xmit);
2461 /*=======================================================================
2463 =======================================================================*/
2465 int netdev_max_backlog __read_mostly = 1000;
2466 int netdev_tstamp_prequeue __read_mostly = 1;
2467 int netdev_budget __read_mostly = 300;
2468 int weight_p __read_mostly = 64; /* old backlog weight */
2470 /* Called with irq disabled */
2471 static inline void ____napi_schedule(struct softnet_data *sd,
2472 struct napi_struct *napi)
2474 list_add_tail(&napi->poll_list, &sd->poll_list);
2475 __raise_softirq_irqoff(NET_RX_SOFTIRQ);
2479 * __skb_get_rxhash: calculate a flow hash based on src/dst addresses
2480 * and src/dst port numbers. Returns a non-zero hash number on success
2483 __u32 __skb_get_rxhash(struct sk_buff *skb)
2485 int nhoff, hash = 0, poff;
2486 struct ipv6hdr *ip6;
2489 u32 addr1, addr2, ihl;
2495 nhoff = skb_network_offset(skb);
2497 switch (skb->protocol) {
2498 case __constant_htons(ETH_P_IP):
2499 if (!pskb_may_pull(skb, sizeof(*ip) + nhoff))
2502 ip = (struct iphdr *) (skb->data + nhoff);
2503 if (ip->frag_off & htons(IP_MF | IP_OFFSET))
2506 ip_proto = ip->protocol;
2507 addr1 = (__force u32) ip->saddr;
2508 addr2 = (__force u32) ip->daddr;
2511 case __constant_htons(ETH_P_IPV6):
2512 if (!pskb_may_pull(skb, sizeof(*ip6) + nhoff))
2515 ip6 = (struct ipv6hdr *) (skb->data + nhoff);
2516 ip_proto = ip6->nexthdr;
2517 addr1 = (__force u32) ip6->saddr.s6_addr32[3];
2518 addr2 = (__force u32) ip6->daddr.s6_addr32[3];
2526 poff = proto_ports_offset(ip_proto);
2528 nhoff += ihl * 4 + poff;
2529 if (pskb_may_pull(skb, nhoff + 4)) {
2530 ports.v32 = * (__force u32 *) (skb->data + nhoff);
2531 if (ports.v16[1] < ports.v16[0])
2532 swap(ports.v16[0], ports.v16[1]);
2536 /* get a consistent hash (same value on both flow directions) */
2540 hash = jhash_3words(addr1, addr2, ports.v32, hashrnd);
2547 EXPORT_SYMBOL(__skb_get_rxhash);
2551 /* One global table that all flow-based protocols share. */
2552 struct rps_sock_flow_table __rcu *rps_sock_flow_table __read_mostly;
2553 EXPORT_SYMBOL(rps_sock_flow_table);
2556 * get_rps_cpu is called from netif_receive_skb and returns the target
2557 * CPU from the RPS map of the receiving queue for a given skb.
2558 * rcu_read_lock must be held on entry.
2560 static int get_rps_cpu(struct net_device *dev, struct sk_buff *skb,
2561 struct rps_dev_flow **rflowp)
2563 struct netdev_rx_queue *rxqueue;
2564 struct rps_map *map;
2565 struct rps_dev_flow_table *flow_table;
2566 struct rps_sock_flow_table *sock_flow_table;
2570 if (skb_rx_queue_recorded(skb)) {
2571 u16 index = skb_get_rx_queue(skb);
2572 if (unlikely(index >= dev->real_num_rx_queues)) {
2573 WARN_ONCE(dev->real_num_rx_queues > 1,
2574 "%s received packet on queue %u, but number "
2575 "of RX queues is %u\n",
2576 dev->name, index, dev->real_num_rx_queues);
2579 rxqueue = dev->_rx + index;
2583 map = rcu_dereference(rxqueue->rps_map);
2585 if (map->len == 1) {
2586 tcpu = map->cpus[0];
2587 if (cpu_online(tcpu))
2591 } else if (!rcu_dereference_raw(rxqueue->rps_flow_table)) {
2595 skb_reset_network_header(skb);
2596 if (!skb_get_rxhash(skb))
2599 flow_table = rcu_dereference(rxqueue->rps_flow_table);
2600 sock_flow_table = rcu_dereference(rps_sock_flow_table);
2601 if (flow_table && sock_flow_table) {
2603 struct rps_dev_flow *rflow;
2605 rflow = &flow_table->flows[skb->rxhash & flow_table->mask];
2608 next_cpu = sock_flow_table->ents[skb->rxhash &
2609 sock_flow_table->mask];
2612 * If the desired CPU (where last recvmsg was done) is
2613 * different from current CPU (one in the rx-queue flow
2614 * table entry), switch if one of the following holds:
2615 * - Current CPU is unset (equal to RPS_NO_CPU).
2616 * - Current CPU is offline.
2617 * - The current CPU's queue tail has advanced beyond the
2618 * last packet that was enqueued using this table entry.
2619 * This guarantees that all previous packets for the flow
2620 * have been dequeued, thus preserving in order delivery.
2622 if (unlikely(tcpu != next_cpu) &&
2623 (tcpu == RPS_NO_CPU || !cpu_online(tcpu) ||
2624 ((int)(per_cpu(softnet_data, tcpu).input_queue_head -
2625 rflow->last_qtail)) >= 0)) {
2626 tcpu = rflow->cpu = next_cpu;
2627 if (tcpu != RPS_NO_CPU)
2628 rflow->last_qtail = per_cpu(softnet_data,
2629 tcpu).input_queue_head;
2631 if (tcpu != RPS_NO_CPU && cpu_online(tcpu)) {
2639 tcpu = map->cpus[((u64) skb->rxhash * map->len) >> 32];
2641 if (cpu_online(tcpu)) {
2651 /* Called from hardirq (IPI) context */
2652 static void rps_trigger_softirq(void *data)
2654 struct softnet_data *sd = data;
2656 ____napi_schedule(sd, &sd->backlog);
2660 #endif /* CONFIG_RPS */
2663 * Check if this softnet_data structure is another cpu one
2664 * If yes, queue it to our IPI list and return 1
2667 static int rps_ipi_queued(struct softnet_data *sd)
2670 struct softnet_data *mysd = &__get_cpu_var(softnet_data);
2673 sd->rps_ipi_next = mysd->rps_ipi_list;
2674 mysd->rps_ipi_list = sd;
2676 __raise_softirq_irqoff(NET_RX_SOFTIRQ);
2679 #endif /* CONFIG_RPS */
2684 * enqueue_to_backlog is called to queue an skb to a per CPU backlog
2685 * queue (may be a remote CPU queue).
2687 static int enqueue_to_backlog(struct sk_buff *skb, int cpu,
2688 unsigned int *qtail)
2690 struct softnet_data *sd;
2691 unsigned long flags;
2693 sd = &per_cpu(softnet_data, cpu);
2695 local_irq_save(flags);
2698 if (skb_queue_len(&sd->input_pkt_queue) <= netdev_max_backlog) {
2699 if (skb_queue_len(&sd->input_pkt_queue)) {
2701 __skb_queue_tail(&sd->input_pkt_queue, skb);
2702 input_queue_tail_incr_save(sd, qtail);
2704 local_irq_restore(flags);
2705 return NET_RX_SUCCESS;
2708 /* Schedule NAPI for backlog device
2709 * We can use non atomic operation since we own the queue lock
2711 if (!__test_and_set_bit(NAPI_STATE_SCHED, &sd->backlog.state)) {
2712 if (!rps_ipi_queued(sd))
2713 ____napi_schedule(sd, &sd->backlog);
2721 local_irq_restore(flags);
2723 atomic_long_inc(&skb->dev->rx_dropped);
2729 * netif_rx - post buffer to the network code
2730 * @skb: buffer to post
2732 * This function receives a packet from a device driver and queues it for
2733 * the upper (protocol) levels to process. It always succeeds. The buffer
2734 * may be dropped during processing for congestion control or by the
2738 * NET_RX_SUCCESS (no congestion)
2739 * NET_RX_DROP (packet was dropped)
2743 int netif_rx(struct sk_buff *skb)
2747 /* if netpoll wants it, pretend we never saw it */
2748 if (netpoll_rx(skb))
2751 if (netdev_tstamp_prequeue)
2752 net_timestamp_check(skb);
2754 trace_netif_rx(skb);
2757 struct rps_dev_flow voidflow, *rflow = &voidflow;
2763 cpu = get_rps_cpu(skb->dev, skb, &rflow);
2765 cpu = smp_processor_id();
2767 ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail);
2775 ret = enqueue_to_backlog(skb, get_cpu(), &qtail);
2781 EXPORT_SYMBOL(netif_rx);
2783 int netif_rx_ni(struct sk_buff *skb)
2788 err = netif_rx(skb);
2789 if (local_softirq_pending())
2795 EXPORT_SYMBOL(netif_rx_ni);
2797 static void net_tx_action(struct softirq_action *h)
2799 struct softnet_data *sd = &__get_cpu_var(softnet_data);
2801 if (sd->completion_queue) {
2802 struct sk_buff *clist;
2804 local_irq_disable();
2805 clist = sd->completion_queue;
2806 sd->completion_queue = NULL;
2810 struct sk_buff *skb = clist;
2811 clist = clist->next;
2813 WARN_ON(atomic_read(&skb->users));
2814 trace_kfree_skb(skb, net_tx_action);
2819 if (sd->output_queue) {
2822 local_irq_disable();
2823 head = sd->output_queue;
2824 sd->output_queue = NULL;
2825 sd->output_queue_tailp = &sd->output_queue;
2829 struct Qdisc *q = head;
2830 spinlock_t *root_lock;
2832 head = head->next_sched;
2834 root_lock = qdisc_lock(q);
2835 if (spin_trylock(root_lock)) {
2836 smp_mb__before_clear_bit();
2837 clear_bit(__QDISC_STATE_SCHED,
2840 spin_unlock(root_lock);
2842 if (!test_bit(__QDISC_STATE_DEACTIVATED,
2844 __netif_reschedule(q);
2846 smp_mb__before_clear_bit();
2847 clear_bit(__QDISC_STATE_SCHED,
2855 #if (defined(CONFIG_BRIDGE) || defined(CONFIG_BRIDGE_MODULE)) && \
2856 (defined(CONFIG_ATM_LANE) || defined(CONFIG_ATM_LANE_MODULE))
2857 /* This hook is defined here for ATM LANE */
2858 int (*br_fdb_test_addr_hook)(struct net_device *dev,
2859 unsigned char *addr) __read_mostly;
2860 EXPORT_SYMBOL_GPL(br_fdb_test_addr_hook);
2863 #ifdef CONFIG_NET_CLS_ACT
2864 /* TODO: Maybe we should just force sch_ingress to be compiled in
2865 * when CONFIG_NET_CLS_ACT is? otherwise some useless instructions
2866 * a compare and 2 stores extra right now if we dont have it on
2867 * but have CONFIG_NET_CLS_ACT
2868 * NOTE: This doesnt stop any functionality; if you dont have
2869 * the ingress scheduler, you just cant add policies on ingress.
2872 static int ing_filter(struct sk_buff *skb, struct netdev_queue *rxq)
2874 struct net_device *dev = skb->dev;
2875 u32 ttl = G_TC_RTTL(skb->tc_verd);
2876 int result = TC_ACT_OK;
2879 if (unlikely(MAX_RED_LOOP < ttl++)) {
2880 if (net_ratelimit())
2881 pr_warning( "Redir loop detected Dropping packet (%d->%d)\n",
2882 skb->skb_iif, dev->ifindex);
2886 skb->tc_verd = SET_TC_RTTL(skb->tc_verd, ttl);
2887 skb->tc_verd = SET_TC_AT(skb->tc_verd, AT_INGRESS);
2890 if (q != &noop_qdisc) {
2891 spin_lock(qdisc_lock(q));
2892 if (likely(!test_bit(__QDISC_STATE_DEACTIVATED, &q->state)))
2893 result = qdisc_enqueue_root(skb, q);
2894 spin_unlock(qdisc_lock(q));
2900 static inline struct sk_buff *handle_ing(struct sk_buff *skb,
2901 struct packet_type **pt_prev,
2902 int *ret, struct net_device *orig_dev)
2904 struct netdev_queue *rxq = rcu_dereference(skb->dev->ingress_queue);
2906 if (!rxq || rxq->qdisc == &noop_qdisc)
2910 *ret = deliver_skb(skb, *pt_prev, orig_dev);
2914 switch (ing_filter(skb, rxq)) {
2928 * netdev_rx_handler_register - register receive handler
2929 * @dev: device to register a handler for
2930 * @rx_handler: receive handler to register
2931 * @rx_handler_data: data pointer that is used by rx handler
2933 * Register a receive hander for a device. This handler will then be
2934 * called from __netif_receive_skb. A negative errno code is returned
2937 * The caller must hold the rtnl_mutex.
2939 int netdev_rx_handler_register(struct net_device *dev,
2940 rx_handler_func_t *rx_handler,
2941 void *rx_handler_data)
2945 if (dev->rx_handler)
2948 rcu_assign_pointer(dev->rx_handler_data, rx_handler_data);
2949 rcu_assign_pointer(dev->rx_handler, rx_handler);
2953 EXPORT_SYMBOL_GPL(netdev_rx_handler_register);
2956 * netdev_rx_handler_unregister - unregister receive handler
2957 * @dev: device to unregister a handler from
2959 * Unregister a receive hander from a device.
2961 * The caller must hold the rtnl_mutex.
2963 void netdev_rx_handler_unregister(struct net_device *dev)
2967 rcu_assign_pointer(dev->rx_handler, NULL);
2968 rcu_assign_pointer(dev->rx_handler_data, NULL);
2970 EXPORT_SYMBOL_GPL(netdev_rx_handler_unregister);
2972 static inline void skb_bond_set_mac_by_master(struct sk_buff *skb,
2973 struct net_device *master)
2975 if (skb->pkt_type == PACKET_HOST) {
2976 u16 *dest = (u16 *) eth_hdr(skb)->h_dest;
2978 memcpy(dest, master->dev_addr, ETH_ALEN);
2982 /* On bonding slaves other than the currently active slave, suppress
2983 * duplicates except for 802.3ad ETH_P_SLOW, alb non-mcast/bcast, and
2984 * ARP on active-backup slaves with arp_validate enabled.
2986 int __skb_bond_should_drop(struct sk_buff *skb, struct net_device *master)
2988 struct net_device *dev = skb->dev;
2990 if (master->priv_flags & IFF_MASTER_ARPMON)
2991 dev->last_rx = jiffies;
2993 if ((master->priv_flags & IFF_MASTER_ALB) &&
2994 (master->priv_flags & IFF_BRIDGE_PORT)) {
2995 /* Do address unmangle. The local destination address
2996 * will be always the one master has. Provides the right
2997 * functionality in a bridge.
2999 skb_bond_set_mac_by_master(skb, master);
3002 if (dev->priv_flags & IFF_SLAVE_INACTIVE) {
3003 if ((dev->priv_flags & IFF_SLAVE_NEEDARP) &&
3004 skb->protocol == __cpu_to_be16(ETH_P_ARP))
3007 if (master->priv_flags & IFF_MASTER_ALB) {
3008 if (skb->pkt_type != PACKET_BROADCAST &&
3009 skb->pkt_type != PACKET_MULTICAST)
3012 if (master->priv_flags & IFF_MASTER_8023AD &&
3013 skb->protocol == __cpu_to_be16(ETH_P_SLOW))
3020 EXPORT_SYMBOL(__skb_bond_should_drop);
3022 static int __netif_receive_skb(struct sk_buff *skb)
3024 struct packet_type *ptype, *pt_prev;
3025 rx_handler_func_t *rx_handler;
3026 struct net_device *orig_dev;
3027 struct net_device *master;
3028 struct net_device *null_or_orig;
3029 struct net_device *orig_or_bond;
3030 int ret = NET_RX_DROP;
3033 if (!netdev_tstamp_prequeue)
3034 net_timestamp_check(skb);
3036 trace_netif_receive_skb(skb);
3038 /* if we've gotten here through NAPI, check netpoll */
3039 if (netpoll_receive_skb(skb))
3043 skb->skb_iif = skb->dev->ifindex;
3046 * bonding note: skbs received on inactive slaves should only
3047 * be delivered to pkt handlers that are exact matches. Also
3048 * the deliver_no_wcard flag will be set. If packet handlers
3049 * are sensitive to duplicate packets these skbs will need to
3050 * be dropped at the handler.
3052 null_or_orig = NULL;
3053 orig_dev = skb->dev;
3054 master = ACCESS_ONCE(orig_dev->master);
3055 if (skb->deliver_no_wcard)
3056 null_or_orig = orig_dev;
3058 if (skb_bond_should_drop(skb, master)) {
3059 skb->deliver_no_wcard = 1;
3060 null_or_orig = orig_dev; /* deliver only exact match */
3065 __this_cpu_inc(softnet_data.processed);
3066 skb_reset_network_header(skb);
3067 skb_reset_transport_header(skb);
3068 skb->mac_len = skb->network_header - skb->mac_header;
3074 #ifdef CONFIG_NET_CLS_ACT
3075 if (skb->tc_verd & TC_NCLS) {
3076 skb->tc_verd = CLR_TC_NCLS(skb->tc_verd);
3081 list_for_each_entry_rcu(ptype, &ptype_all, list) {
3082 if (ptype->dev == null_or_orig || ptype->dev == skb->dev ||
3083 ptype->dev == orig_dev) {
3085 ret = deliver_skb(skb, pt_prev, orig_dev);
3090 #ifdef CONFIG_NET_CLS_ACT
3091 skb = handle_ing(skb, &pt_prev, &ret, orig_dev);
3097 /* Handle special case of bridge or macvlan */
3098 rx_handler = rcu_dereference(skb->dev->rx_handler);
3101 ret = deliver_skb(skb, pt_prev, orig_dev);
3104 skb = rx_handler(skb);
3109 if (vlan_tx_tag_present(skb)) {
3111 ret = deliver_skb(skb, pt_prev, orig_dev);
3114 if (vlan_hwaccel_do_receive(&skb)) {
3115 ret = __netif_receive_skb(skb);
3117 } else if (unlikely(!skb))
3122 * Make sure frames received on VLAN interfaces stacked on
3123 * bonding interfaces still make their way to any base bonding
3124 * device that may have registered for a specific ptype. The
3125 * handler may have to adjust skb->dev and orig_dev.
3127 orig_or_bond = orig_dev;
3128 if ((skb->dev->priv_flags & IFF_802_1Q_VLAN) &&
3129 (vlan_dev_real_dev(skb->dev)->priv_flags & IFF_BONDING)) {
3130 orig_or_bond = vlan_dev_real_dev(skb->dev);
3133 type = skb->protocol;
3134 list_for_each_entry_rcu(ptype,
3135 &ptype_base[ntohs(type) & PTYPE_HASH_MASK], list) {
3136 if (ptype->type == type && (ptype->dev == null_or_orig ||
3137 ptype->dev == skb->dev || ptype->dev == orig_dev ||
3138 ptype->dev == orig_or_bond)) {
3140 ret = deliver_skb(skb, pt_prev, orig_dev);
3146 ret = pt_prev->func(skb, skb->dev, pt_prev, orig_dev);
3148 atomic_long_inc(&skb->dev->rx_dropped);
3150 /* Jamal, now you will not able to escape explaining
3151 * me how you were going to use this. :-)
3162 * netif_receive_skb - process receive buffer from network
3163 * @skb: buffer to process
3165 * netif_receive_skb() is the main receive data processing function.
3166 * It always succeeds. The buffer may be dropped during processing
3167 * for congestion control or by the protocol layers.
3169 * This function may only be called from softirq context and interrupts
3170 * should be enabled.
3172 * Return values (usually ignored):
3173 * NET_RX_SUCCESS: no congestion
3174 * NET_RX_DROP: packet was dropped
3176 int netif_receive_skb(struct sk_buff *skb)
3178 if (netdev_tstamp_prequeue)
3179 net_timestamp_check(skb);
3181 if (skb_defer_rx_timestamp(skb))
3182 return NET_RX_SUCCESS;
3186 struct rps_dev_flow voidflow, *rflow = &voidflow;
3191 cpu = get_rps_cpu(skb->dev, skb, &rflow);
3194 ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail);
3198 ret = __netif_receive_skb(skb);
3204 return __netif_receive_skb(skb);
3207 EXPORT_SYMBOL(netif_receive_skb);
3209 /* Network device is going away, flush any packets still pending
3210 * Called with irqs disabled.
3212 static void flush_backlog(void *arg)
3214 struct net_device *dev = arg;
3215 struct softnet_data *sd = &__get_cpu_var(softnet_data);
3216 struct sk_buff *skb, *tmp;
3219 skb_queue_walk_safe(&sd->input_pkt_queue, skb, tmp) {
3220 if (skb->dev == dev) {
3221 __skb_unlink(skb, &sd->input_pkt_queue);
3223 input_queue_head_incr(sd);
3228 skb_queue_walk_safe(&sd->process_queue, skb, tmp) {
3229 if (skb->dev == dev) {
3230 __skb_unlink(skb, &sd->process_queue);
3232 input_queue_head_incr(sd);
3237 static int napi_gro_complete(struct sk_buff *skb)
3239 struct packet_type *ptype;
3240 __be16 type = skb->protocol;
3241 struct list_head *head = &ptype_base[ntohs(type) & PTYPE_HASH_MASK];
3244 if (NAPI_GRO_CB(skb)->count == 1) {
3245 skb_shinfo(skb)->gso_size = 0;
3250 list_for_each_entry_rcu(ptype, head, list) {
3251 if (ptype->type != type || ptype->dev || !ptype->gro_complete)
3254 err = ptype->gro_complete(skb);
3260 WARN_ON(&ptype->list == head);
3262 return NET_RX_SUCCESS;
3266 return netif_receive_skb(skb);
3269 inline void napi_gro_flush(struct napi_struct *napi)
3271 struct sk_buff *skb, *next;
3273 for (skb = napi->gro_list; skb; skb = next) {
3276 napi_gro_complete(skb);
3279 napi->gro_count = 0;
3280 napi->gro_list = NULL;
3282 EXPORT_SYMBOL(napi_gro_flush);
3284 enum gro_result dev_gro_receive(struct napi_struct *napi, struct sk_buff *skb)
3286 struct sk_buff **pp = NULL;
3287 struct packet_type *ptype;
3288 __be16 type = skb->protocol;
3289 struct list_head *head = &ptype_base[ntohs(type) & PTYPE_HASH_MASK];
3292 enum gro_result ret;
3294 if (!(skb->dev->features & NETIF_F_GRO) || netpoll_rx_on(skb))
3297 if (skb_is_gso(skb) || skb_has_frag_list(skb))
3301 list_for_each_entry_rcu(ptype, head, list) {
3302 if (ptype->type != type || ptype->dev || !ptype->gro_receive)
3305 skb_set_network_header(skb, skb_gro_offset(skb));
3306 mac_len = skb->network_header - skb->mac_header;
3307 skb->mac_len = mac_len;
3308 NAPI_GRO_CB(skb)->same_flow = 0;
3309 NAPI_GRO_CB(skb)->flush = 0;
3310 NAPI_GRO_CB(skb)->free = 0;
3312 pp = ptype->gro_receive(&napi->gro_list, skb);
3317 if (&ptype->list == head)
3320 same_flow = NAPI_GRO_CB(skb)->same_flow;
3321 ret = NAPI_GRO_CB(skb)->free ? GRO_MERGED_FREE : GRO_MERGED;
3324 struct sk_buff *nskb = *pp;
3328 napi_gro_complete(nskb);
3335 if (NAPI_GRO_CB(skb)->flush || napi->gro_count >= MAX_GRO_SKBS)
3339 NAPI_GRO_CB(skb)->count = 1;
3340 skb_shinfo(skb)->gso_size = skb_gro_len(skb);
3341 skb->next = napi->gro_list;
3342 napi->gro_list = skb;
3346 if (skb_headlen(skb) < skb_gro_offset(skb)) {
3347 int grow = skb_gro_offset(skb) - skb_headlen(skb);
3349 BUG_ON(skb->end - skb->tail < grow);
3351 memcpy(skb_tail_pointer(skb), NAPI_GRO_CB(skb)->frag0, grow);
3354 skb->data_len -= grow;
3356 skb_shinfo(skb)->frags[0].page_offset += grow;
3357 skb_shinfo(skb)->frags[0].size -= grow;
3359 if (unlikely(!skb_shinfo(skb)->frags[0].size)) {
3360 put_page(skb_shinfo(skb)->frags[0].page);
3361 memmove(skb_shinfo(skb)->frags,
3362 skb_shinfo(skb)->frags + 1,
3363 --skb_shinfo(skb)->nr_frags * sizeof(skb_frag_t));
3374 EXPORT_SYMBOL(dev_gro_receive);
3376 static inline gro_result_t
3377 __napi_gro_receive(struct napi_struct *napi, struct sk_buff *skb)
3381 for (p = napi->gro_list; p; p = p->next) {
3382 unsigned long diffs;
3384 diffs = (unsigned long)p->dev ^ (unsigned long)skb->dev;
3385 diffs |= p->vlan_tci ^ skb->vlan_tci;
3386 diffs |= compare_ether_header(skb_mac_header(p),
3387 skb_gro_mac_header(skb));
3388 NAPI_GRO_CB(p)->same_flow = !diffs;
3389 NAPI_GRO_CB(p)->flush = 0;
3392 return dev_gro_receive(napi, skb);
3395 gro_result_t napi_skb_finish(gro_result_t ret, struct sk_buff *skb)
3399 if (netif_receive_skb(skb))
3404 case GRO_MERGED_FREE:
3415 EXPORT_SYMBOL(napi_skb_finish);
3417 void skb_gro_reset_offset(struct sk_buff *skb)
3419 NAPI_GRO_CB(skb)->data_offset = 0;
3420 NAPI_GRO_CB(skb)->frag0 = NULL;
3421 NAPI_GRO_CB(skb)->frag0_len = 0;
3423 if (skb->mac_header == skb->tail &&
3424 !PageHighMem(skb_shinfo(skb)->frags[0].page)) {
3425 NAPI_GRO_CB(skb)->frag0 =
3426 page_address(skb_shinfo(skb)->frags[0].page) +
3427 skb_shinfo(skb)->frags[0].page_offset;
3428 NAPI_GRO_CB(skb)->frag0_len = skb_shinfo(skb)->frags[0].size;
3431 EXPORT_SYMBOL(skb_gro_reset_offset);
3433 gro_result_t napi_gro_receive(struct napi_struct *napi, struct sk_buff *skb)
3435 skb_gro_reset_offset(skb);
3437 return napi_skb_finish(__napi_gro_receive(napi, skb), skb);
3439 EXPORT_SYMBOL(napi_gro_receive);
3441 static void napi_reuse_skb(struct napi_struct *napi, struct sk_buff *skb)
3443 __skb_pull(skb, skb_headlen(skb));
3444 skb_reserve(skb, NET_IP_ALIGN - skb_headroom(skb));
3450 struct sk_buff *napi_get_frags(struct napi_struct *napi)
3452 struct sk_buff *skb = napi->skb;
3455 skb = netdev_alloc_skb_ip_align(napi->dev, GRO_MAX_HEAD);
3461 EXPORT_SYMBOL(napi_get_frags);
3463 gro_result_t napi_frags_finish(struct napi_struct *napi, struct sk_buff *skb,
3469 skb->protocol = eth_type_trans(skb, skb->dev);
3471 if (ret == GRO_HELD)
3472 skb_gro_pull(skb, -ETH_HLEN);
3473 else if (netif_receive_skb(skb))
3478 case GRO_MERGED_FREE:
3479 napi_reuse_skb(napi, skb);
3488 EXPORT_SYMBOL(napi_frags_finish);
3490 struct sk_buff *napi_frags_skb(struct napi_struct *napi)
3492 struct sk_buff *skb = napi->skb;
3499 skb_reset_mac_header(skb);
3500 skb_gro_reset_offset(skb);
3502 off = skb_gro_offset(skb);
3503 hlen = off + sizeof(*eth);
3504 eth = skb_gro_header_fast(skb, off);
3505 if (skb_gro_header_hard(skb, hlen)) {
3506 eth = skb_gro_header_slow(skb, hlen, off);
3507 if (unlikely(!eth)) {
3508 napi_reuse_skb(napi, skb);
3514 skb_gro_pull(skb, sizeof(*eth));
3517 * This works because the only protocols we care about don't require
3518 * special handling. We'll fix it up properly at the end.
3520 skb->protocol = eth->h_proto;
3525 EXPORT_SYMBOL(napi_frags_skb);
3527 gro_result_t napi_gro_frags(struct napi_struct *napi)
3529 struct sk_buff *skb = napi_frags_skb(napi);
3534 return napi_frags_finish(napi, skb, __napi_gro_receive(napi, skb));
3536 EXPORT_SYMBOL(napi_gro_frags);
3539 * net_rps_action sends any pending IPI's for rps.
3540 * Note: called with local irq disabled, but exits with local irq enabled.
3542 static void net_rps_action_and_irq_enable(struct softnet_data *sd)
3545 struct softnet_data *remsd = sd->rps_ipi_list;
3548 sd->rps_ipi_list = NULL;
3552 /* Send pending IPI's to kick RPS processing on remote cpus. */
3554 struct softnet_data *next = remsd->rps_ipi_next;
3556 if (cpu_online(remsd->cpu))
3557 __smp_call_function_single(remsd->cpu,
3566 static int process_backlog(struct napi_struct *napi, int quota)
3569 struct softnet_data *sd = container_of(napi, struct softnet_data, backlog);
3572 /* Check if we have pending ipi, its better to send them now,
3573 * not waiting net_rx_action() end.
3575 if (sd->rps_ipi_list) {
3576 local_irq_disable();
3577 net_rps_action_and_irq_enable(sd);
3580 napi->weight = weight_p;
3581 local_irq_disable();
3582 while (work < quota) {
3583 struct sk_buff *skb;
3586 while ((skb = __skb_dequeue(&sd->process_queue))) {
3588 __netif_receive_skb(skb);
3589 local_irq_disable();
3590 input_queue_head_incr(sd);
3591 if (++work >= quota) {
3598 qlen = skb_queue_len(&sd->input_pkt_queue);
3600 skb_queue_splice_tail_init(&sd->input_pkt_queue,
3601 &sd->process_queue);
3603 if (qlen < quota - work) {
3605 * Inline a custom version of __napi_complete().
3606 * only current cpu owns and manipulates this napi,
3607 * and NAPI_STATE_SCHED is the only possible flag set on backlog.
3608 * we can use a plain write instead of clear_bit(),
3609 * and we dont need an smp_mb() memory barrier.
3611 list_del(&napi->poll_list);
3614 quota = work + qlen;
3624 * __napi_schedule - schedule for receive
3625 * @n: entry to schedule
3627 * The entry's receive function will be scheduled to run
3629 void __napi_schedule(struct napi_struct *n)
3631 unsigned long flags;
3633 local_irq_save(flags);
3634 ____napi_schedule(&__get_cpu_var(softnet_data), n);
3635 local_irq_restore(flags);
3637 EXPORT_SYMBOL(__napi_schedule);
3639 void __napi_complete(struct napi_struct *n)
3641 BUG_ON(!test_bit(NAPI_STATE_SCHED, &n->state));
3642 BUG_ON(n->gro_list);
3644 list_del(&n->poll_list);
3645 smp_mb__before_clear_bit();
3646 clear_bit(NAPI_STATE_SCHED, &n->state);
3648 EXPORT_SYMBOL(__napi_complete);
3650 void napi_complete(struct napi_struct *n)
3652 unsigned long flags;
3655 * don't let napi dequeue from the cpu poll list
3656 * just in case its running on a different cpu
3658 if (unlikely(test_bit(NAPI_STATE_NPSVC, &n->state)))
3662 local_irq_save(flags);
3664 local_irq_restore(flags);
3666 EXPORT_SYMBOL(napi_complete);
3668 void netif_napi_add(struct net_device *dev, struct napi_struct *napi,
3669 int (*poll)(struct napi_struct *, int), int weight)
3671 INIT_LIST_HEAD(&napi->poll_list);
3672 napi->gro_count = 0;
3673 napi->gro_list = NULL;
3676 napi->weight = weight;
3677 list_add(&napi->dev_list, &dev->napi_list);
3679 #ifdef CONFIG_NETPOLL
3680 spin_lock_init(&napi->poll_lock);
3681 napi->poll_owner = -1;
3683 set_bit(NAPI_STATE_SCHED, &napi->state);
3685 EXPORT_SYMBOL(netif_napi_add);
3687 void netif_napi_del(struct napi_struct *napi)
3689 struct sk_buff *skb, *next;
3691 list_del_init(&napi->dev_list);
3692 napi_free_frags(napi);
3694 for (skb = napi->gro_list; skb; skb = next) {
3700 napi->gro_list = NULL;
3701 napi->gro_count = 0;
3703 EXPORT_SYMBOL(netif_napi_del);
3705 static void net_rx_action(struct softirq_action *h)
3707 struct softnet_data *sd = &__get_cpu_var(softnet_data);
3708 unsigned long time_limit = jiffies + 2;
3709 int budget = netdev_budget;
3712 local_irq_disable();
3714 while (!list_empty(&sd->poll_list)) {
3715 struct napi_struct *n;
3718 /* If softirq window is exhuasted then punt.
3719 * Allow this to run for 2 jiffies since which will allow
3720 * an average latency of 1.5/HZ.
3722 if (unlikely(budget <= 0 || time_after(jiffies, time_limit)))
3727 /* Even though interrupts have been re-enabled, this
3728 * access is safe because interrupts can only add new
3729 * entries to the tail of this list, and only ->poll()
3730 * calls can remove this head entry from the list.
3732 n = list_first_entry(&sd->poll_list, struct napi_struct, poll_list);
3734 have = netpoll_poll_lock(n);
3738 /* This NAPI_STATE_SCHED test is for avoiding a race
3739 * with netpoll's poll_napi(). Only the entity which
3740 * obtains the lock and sees NAPI_STATE_SCHED set will
3741 * actually make the ->poll() call. Therefore we avoid
3742 * accidently calling ->poll() when NAPI is not scheduled.
3745 if (test_bit(NAPI_STATE_SCHED, &n->state)) {
3746 work = n->poll(n, weight);
3750 WARN_ON_ONCE(work > weight);
3754 local_irq_disable();
3756 /* Drivers must not modify the NAPI state if they
3757 * consume the entire weight. In such cases this code
3758 * still "owns" the NAPI instance and therefore can
3759 * move the instance around on the list at-will.
3761 if (unlikely(work == weight)) {
3762 if (unlikely(napi_disable_pending(n))) {
3765 local_irq_disable();
3767 list_move_tail(&n->poll_list, &sd->poll_list);
3770 netpoll_poll_unlock(have);
3773 net_rps_action_and_irq_enable(sd);
3775 #ifdef CONFIG_NET_DMA
3777 * There may not be any more sk_buffs coming right now, so push
3778 * any pending DMA copies to hardware
3780 dma_issue_pending_all();
3787 __raise_softirq_irqoff(NET_RX_SOFTIRQ);
3791 static gifconf_func_t *gifconf_list[NPROTO];
3794 * register_gifconf - register a SIOCGIF handler
3795 * @family: Address family
3796 * @gifconf: Function handler
3798 * Register protocol dependent address dumping routines. The handler
3799 * that is passed must not be freed or reused until it has been replaced
3800 * by another handler.
3802 int register_gifconf(unsigned int family, gifconf_func_t *gifconf)
3804 if (family >= NPROTO)
3806 gifconf_list[family] = gifconf;
3809 EXPORT_SYMBOL(register_gifconf);
3813 * Map an interface index to its name (SIOCGIFNAME)
3817 * We need this ioctl for efficient implementation of the
3818 * if_indextoname() function required by the IPv6 API. Without
3819 * it, we would have to search all the interfaces to find a
3823 static int dev_ifname(struct net *net, struct ifreq __user *arg)
3825 struct net_device *dev;
3829 * Fetch the caller's info block.
3832 if (copy_from_user(&ifr, arg, sizeof(struct ifreq)))
3836 dev = dev_get_by_index_rcu(net, ifr.ifr_ifindex);
3842 strcpy(ifr.ifr_name, dev->name);
3845 if (copy_to_user(arg, &ifr, sizeof(struct ifreq)))
3851 * Perform a SIOCGIFCONF call. This structure will change
3852 * size eventually, and there is nothing I can do about it.
3853 * Thus we will need a 'compatibility mode'.
3856 static int dev_ifconf(struct net *net, char __user *arg)
3859 struct net_device *dev;
3866 * Fetch the caller's info block.
3869 if (copy_from_user(&ifc, arg, sizeof(struct ifconf)))
3876 * Loop over the interfaces, and write an info block for each.
3880 for_each_netdev(net, dev) {
3881 for (i = 0; i < NPROTO; i++) {
3882 if (gifconf_list[i]) {
3885 done = gifconf_list[i](dev, NULL, 0);
3887 done = gifconf_list[i](dev, pos + total,
3897 * All done. Write the updated control block back to the caller.
3899 ifc.ifc_len = total;
3902 * Both BSD and Solaris return 0 here, so we do too.
3904 return copy_to_user(arg, &ifc, sizeof(struct ifconf)) ? -EFAULT : 0;
3907 #ifdef CONFIG_PROC_FS
3909 * This is invoked by the /proc filesystem handler to display a device
3912 void *dev_seq_start(struct seq_file *seq, loff_t *pos)
3915 struct net *net = seq_file_net(seq);
3917 struct net_device *dev;
3921 return SEQ_START_TOKEN;
3924 for_each_netdev_rcu(net, dev)
3931 void *dev_seq_next(struct seq_file *seq, void *v, loff_t *pos)
3933 struct net_device *dev = (v == SEQ_START_TOKEN) ?
3934 first_net_device(seq_file_net(seq)) :
3935 next_net_device((struct net_device *)v);
3938 return rcu_dereference(dev);
3941 void dev_seq_stop(struct seq_file *seq, void *v)
3947 static void dev_seq_printf_stats(struct seq_file *seq, struct net_device *dev)
3949 struct rtnl_link_stats64 temp;
3950 const struct rtnl_link_stats64 *stats = dev_get_stats(dev, &temp);
3952 seq_printf(seq, "%6s: %7llu %7llu %4llu %4llu %4llu %5llu %10llu %9llu "
3953 "%8llu %7llu %4llu %4llu %4llu %5llu %7llu %10llu\n",
3954 dev->name, stats->rx_bytes, stats->rx_packets,
3956 stats->rx_dropped + stats->rx_missed_errors,
3957 stats->rx_fifo_errors,
3958 stats->rx_length_errors + stats->rx_over_errors +
3959 stats->rx_crc_errors + stats->rx_frame_errors,
3960 stats->rx_compressed, stats->multicast,
3961 stats->tx_bytes, stats->tx_packets,
3962 stats->tx_errors, stats->tx_dropped,
3963 stats->tx_fifo_errors, stats->collisions,
3964 stats->tx_carrier_errors +
3965 stats->tx_aborted_errors +
3966 stats->tx_window_errors +
3967 stats->tx_heartbeat_errors,
3968 stats->tx_compressed);
3972 * Called from the PROCfs module. This now uses the new arbitrary sized
3973 * /proc/net interface to create /proc/net/dev
3975 static int dev_seq_show(struct seq_file *seq, void *v)
3977 if (v == SEQ_START_TOKEN)
3978 seq_puts(seq, "Inter-| Receive "
3980 " face |bytes packets errs drop fifo frame "
3981 "compressed multicast|bytes packets errs "
3982 "drop fifo colls carrier compressed\n");
3984 dev_seq_printf_stats(seq, v);
3988 static struct softnet_data *softnet_get_online(loff_t *pos)
3990 struct softnet_data *sd = NULL;
3992 while (*pos < nr_cpu_ids)
3993 if (cpu_online(*pos)) {
3994 sd = &per_cpu(softnet_data, *pos);
4001 static void *softnet_seq_start(struct seq_file *seq, loff_t *pos)
4003 return softnet_get_online(pos);
4006 static void *softnet_seq_next(struct seq_file *seq, void *v, loff_t *pos)
4009 return softnet_get_online(pos);
4012 static void softnet_seq_stop(struct seq_file *seq, void *v)
4016 static int softnet_seq_show(struct seq_file *seq, void *v)
4018 struct softnet_data *sd = v;
4020 seq_printf(seq, "%08x %08x %08x %08x %08x %08x %08x %08x %08x %08x\n",
4021 sd->processed, sd->dropped, sd->time_squeeze, 0,
4022 0, 0, 0, 0, /* was fastroute */
4023 sd->cpu_collision, sd->received_rps);
4027 static const struct seq_operations dev_seq_ops = {
4028 .start = dev_seq_start,
4029 .next = dev_seq_next,
4030 .stop = dev_seq_stop,
4031 .show = dev_seq_show,
4034 static int dev_seq_open(struct inode *inode, struct file *file)
4036 return seq_open_net(inode, file, &dev_seq_ops,
4037 sizeof(struct seq_net_private));
4040 static const struct file_operations dev_seq_fops = {
4041 .owner = THIS_MODULE,
4042 .open = dev_seq_open,
4044 .llseek = seq_lseek,
4045 .release = seq_release_net,
4048 static const struct seq_operations softnet_seq_ops = {
4049 .start = softnet_seq_start,
4050 .next = softnet_seq_next,
4051 .stop = softnet_seq_stop,
4052 .show = softnet_seq_show,
4055 static int softnet_seq_open(struct inode *inode, struct file *file)
4057 return seq_open(file, &softnet_seq_ops);
4060 static const struct file_operations softnet_seq_fops = {
4061 .owner = THIS_MODULE,
4062 .open = softnet_seq_open,
4064 .llseek = seq_lseek,
4065 .release = seq_release,
4068 static void *ptype_get_idx(loff_t pos)
4070 struct packet_type *pt = NULL;
4074 list_for_each_entry_rcu(pt, &ptype_all, list) {
4080 for (t = 0; t < PTYPE_HASH_SIZE; t++) {
4081 list_for_each_entry_rcu(pt, &ptype_base[t], list) {
4090 static void *ptype_seq_start(struct seq_file *seq, loff_t *pos)
4094 return *pos ? ptype_get_idx(*pos - 1) : SEQ_START_TOKEN;
4097 static void *ptype_seq_next(struct seq_file *seq, void *v, loff_t *pos)
4099 struct packet_type *pt;
4100 struct list_head *nxt;
4104 if (v == SEQ_START_TOKEN)
4105 return ptype_get_idx(0);
4108 nxt = pt->list.next;
4109 if (pt->type == htons(ETH_P_ALL)) {
4110 if (nxt != &ptype_all)
4113 nxt = ptype_base[0].next;
4115 hash = ntohs(pt->type) & PTYPE_HASH_MASK;
4117 while (nxt == &ptype_base[hash]) {
4118 if (++hash >= PTYPE_HASH_SIZE)
4120 nxt = ptype_base[hash].next;
4123 return list_entry(nxt, struct packet_type, list);
4126 static void ptype_seq_stop(struct seq_file *seq, void *v)
4132 static int ptype_seq_show(struct seq_file *seq, void *v)
4134 struct packet_type *pt = v;
4136 if (v == SEQ_START_TOKEN)
4137 seq_puts(seq, "Type Device Function\n");
4138 else if (pt->dev == NULL || dev_net(pt->dev) == seq_file_net(seq)) {
4139 if (pt->type == htons(ETH_P_ALL))
4140 seq_puts(seq, "ALL ");
4142 seq_printf(seq, "%04x", ntohs(pt->type));
4144 seq_printf(seq, " %-8s %pF\n",
4145 pt->dev ? pt->dev->name : "", pt->func);
4151 static const struct seq_operations ptype_seq_ops = {
4152 .start = ptype_seq_start,
4153 .next = ptype_seq_next,
4154 .stop = ptype_seq_stop,
4155 .show = ptype_seq_show,
4158 static int ptype_seq_open(struct inode *inode, struct file *file)
4160 return seq_open_net(inode, file, &ptype_seq_ops,
4161 sizeof(struct seq_net_private));
4164 static const struct file_operations ptype_seq_fops = {
4165 .owner = THIS_MODULE,
4166 .open = ptype_seq_open,
4168 .llseek = seq_lseek,
4169 .release = seq_release_net,
4173 static int __net_init dev_proc_net_init(struct net *net)
4177 if (!proc_net_fops_create(net, "dev", S_IRUGO, &dev_seq_fops))
4179 if (!proc_net_fops_create(net, "softnet_stat", S_IRUGO, &softnet_seq_fops))
4181 if (!proc_net_fops_create(net, "ptype", S_IRUGO, &ptype_seq_fops))
4184 if (wext_proc_init(net))
4190 proc_net_remove(net, "ptype");
4192 proc_net_remove(net, "softnet_stat");
4194 proc_net_remove(net, "dev");
4198 static void __net_exit dev_proc_net_exit(struct net *net)
4200 wext_proc_exit(net);
4202 proc_net_remove(net, "ptype");
4203 proc_net_remove(net, "softnet_stat");
4204 proc_net_remove(net, "dev");
4207 static struct pernet_operations __net_initdata dev_proc_ops = {
4208 .init = dev_proc_net_init,
4209 .exit = dev_proc_net_exit,
4212 static int __init dev_proc_init(void)
4214 return register_pernet_subsys(&dev_proc_ops);
4217 #define dev_proc_init() 0
4218 #endif /* CONFIG_PROC_FS */
4222 * netdev_set_master - set up master/slave pair
4223 * @slave: slave device
4224 * @master: new master device
4226 * Changes the master device of the slave. Pass %NULL to break the
4227 * bonding. The caller must hold the RTNL semaphore. On a failure
4228 * a negative errno code is returned. On success the reference counts
4229 * are adjusted, %RTM_NEWLINK is sent to the routing socket and the
4230 * function returns zero.
4232 int netdev_set_master(struct net_device *slave, struct net_device *master)
4234 struct net_device *old = slave->master;
4244 slave->master = master;
4251 slave->flags |= IFF_SLAVE;
4253 slave->flags &= ~IFF_SLAVE;
4255 rtmsg_ifinfo(RTM_NEWLINK, slave, IFF_SLAVE);
4258 EXPORT_SYMBOL(netdev_set_master);
4260 static void dev_change_rx_flags(struct net_device *dev, int flags)
4262 const struct net_device_ops *ops = dev->netdev_ops;
4264 if ((dev->flags & IFF_UP) && ops->ndo_change_rx_flags)
4265 ops->ndo_change_rx_flags(dev, flags);
4268 static int __dev_set_promiscuity(struct net_device *dev, int inc)
4270 unsigned short old_flags = dev->flags;
4276 dev->flags |= IFF_PROMISC;
4277 dev->promiscuity += inc;
4278 if (dev->promiscuity == 0) {
4281 * If inc causes overflow, untouch promisc and return error.
4284 dev->flags &= ~IFF_PROMISC;
4286 dev->promiscuity -= inc;
4287 printk(KERN_WARNING "%s: promiscuity touches roof, "
4288 "set promiscuity failed, promiscuity feature "
4289 "of device might be broken.\n", dev->name);
4293 if (dev->flags != old_flags) {
4294 printk(KERN_INFO "device %s %s promiscuous mode\n",
4295 dev->name, (dev->flags & IFF_PROMISC) ? "entered" :
4297 if (audit_enabled) {
4298 current_uid_gid(&uid, &gid);
4299 audit_log(current->audit_context, GFP_ATOMIC,
4300 AUDIT_ANOM_PROMISCUOUS,
4301 "dev=%s prom=%d old_prom=%d auid=%u uid=%u gid=%u ses=%u",
4302 dev->name, (dev->flags & IFF_PROMISC),
4303 (old_flags & IFF_PROMISC),
4304 audit_get_loginuid(current),
4306 audit_get_sessionid(current));
4309 dev_change_rx_flags(dev, IFF_PROMISC);
4315 * dev_set_promiscuity - update promiscuity count on a device
4319 * Add or remove promiscuity from a device. While the count in the device
4320 * remains above zero the interface remains promiscuous. Once it hits zero
4321 * the device reverts back to normal filtering operation. A negative inc
4322 * value is used to drop promiscuity on the device.
4323 * Return 0 if successful or a negative errno code on error.
4325 int dev_set_promiscuity(struct net_device *dev, int inc)
4327 unsigned short old_flags = dev->flags;
4330 err = __dev_set_promiscuity(dev, inc);
4333 if (dev->flags != old_flags)
4334 dev_set_rx_mode(dev);
4337 EXPORT_SYMBOL(dev_set_promiscuity);
4340 * dev_set_allmulti - update allmulti count on a device
4344 * Add or remove reception of all multicast frames to a device. While the
4345 * count in the device remains above zero the interface remains listening
4346 * to all interfaces. Once it hits zero the device reverts back to normal
4347 * filtering operation. A negative @inc value is used to drop the counter
4348 * when releasing a resource needing all multicasts.
4349 * Return 0 if successful or a negative errno code on error.
4352 int dev_set_allmulti(struct net_device *dev, int inc)
4354 unsigned short old_flags = dev->flags;
4358 dev->flags |= IFF_ALLMULTI;
4359 dev->allmulti += inc;
4360 if (dev->allmulti == 0) {
4363 * If inc causes overflow, untouch allmulti and return error.
4366 dev->flags &= ~IFF_ALLMULTI;
4368 dev->allmulti -= inc;
4369 printk(KERN_WARNING "%s: allmulti touches roof, "
4370 "set allmulti failed, allmulti feature of "
4371 "device might be broken.\n", dev->name);
4375 if (dev->flags ^ old_flags) {
4376 dev_change_rx_flags(dev, IFF_ALLMULTI);
4377 dev_set_rx_mode(dev);
4381 EXPORT_SYMBOL(dev_set_allmulti);
4384 * Upload unicast and multicast address lists to device and
4385 * configure RX filtering. When the device doesn't support unicast
4386 * filtering it is put in promiscuous mode while unicast addresses
4389 void __dev_set_rx_mode(struct net_device *dev)
4391 const struct net_device_ops *ops = dev->netdev_ops;
4393 /* dev_open will call this function so the list will stay sane. */
4394 if (!(dev->flags&IFF_UP))
4397 if (!netif_device_present(dev))
4400 if (ops->ndo_set_rx_mode)
4401 ops->ndo_set_rx_mode(dev);
4403 /* Unicast addresses changes may only happen under the rtnl,
4404 * therefore calling __dev_set_promiscuity here is safe.
4406 if (!netdev_uc_empty(dev) && !dev->uc_promisc) {
4407 __dev_set_promiscuity(dev, 1);
4408 dev->uc_promisc = 1;
4409 } else if (netdev_uc_empty(dev) && dev->uc_promisc) {
4410 __dev_set_promiscuity(dev, -1);
4411 dev->uc_promisc = 0;
4414 if (ops->ndo_set_multicast_list)
4415 ops->ndo_set_multicast_list(dev);
4419 void dev_set_rx_mode(struct net_device *dev)
4421 netif_addr_lock_bh(dev);
4422 __dev_set_rx_mode(dev);
4423 netif_addr_unlock_bh(dev);
4427 * dev_get_flags - get flags reported to userspace
4430 * Get the combination of flag bits exported through APIs to userspace.
4432 unsigned dev_get_flags(const struct net_device *dev)
4436 flags = (dev->flags & ~(IFF_PROMISC |
4441 (dev->gflags & (IFF_PROMISC |
4444 if (netif_running(dev)) {
4445 if (netif_oper_up(dev))
4446 flags |= IFF_RUNNING;
4447 if (netif_carrier_ok(dev))
4448 flags |= IFF_LOWER_UP;
4449 if (netif_dormant(dev))
4450 flags |= IFF_DORMANT;
4455 EXPORT_SYMBOL(dev_get_flags);
4457 int __dev_change_flags(struct net_device *dev, unsigned int flags)
4459 int old_flags = dev->flags;
4465 * Set the flags on our device.
4468 dev->flags = (flags & (IFF_DEBUG | IFF_NOTRAILERS | IFF_NOARP |
4469 IFF_DYNAMIC | IFF_MULTICAST | IFF_PORTSEL |
4471 (dev->flags & (IFF_UP | IFF_VOLATILE | IFF_PROMISC |
4475 * Load in the correct multicast list now the flags have changed.
4478 if ((old_flags ^ flags) & IFF_MULTICAST)
4479 dev_change_rx_flags(dev, IFF_MULTICAST);
4481 dev_set_rx_mode(dev);
4484 * Have we downed the interface. We handle IFF_UP ourselves
4485 * according to user attempts to set it, rather than blindly
4490 if ((old_flags ^ flags) & IFF_UP) { /* Bit is different ? */
4491 ret = ((old_flags & IFF_UP) ? __dev_close : __dev_open)(dev);
4494 dev_set_rx_mode(dev);
4497 if ((flags ^ dev->gflags) & IFF_PROMISC) {
4498 int inc = (flags & IFF_PROMISC) ? 1 : -1;
4500 dev->gflags ^= IFF_PROMISC;
4501 dev_set_promiscuity(dev, inc);
4504 /* NOTE: order of synchronization of IFF_PROMISC and IFF_ALLMULTI
4505 is important. Some (broken) drivers set IFF_PROMISC, when
4506 IFF_ALLMULTI is requested not asking us and not reporting.
4508 if ((flags ^ dev->gflags) & IFF_ALLMULTI) {
4509 int inc = (flags & IFF_ALLMULTI) ? 1 : -1;
4511 dev->gflags ^= IFF_ALLMULTI;
4512 dev_set_allmulti(dev, inc);
4518 void __dev_notify_flags(struct net_device *dev, unsigned int old_flags)
4520 unsigned int changes = dev->flags ^ old_flags;
4522 if (changes & IFF_UP) {
4523 if (dev->flags & IFF_UP)
4524 call_netdevice_notifiers(NETDEV_UP, dev);
4526 call_netdevice_notifiers(NETDEV_DOWN, dev);
4529 if (dev->flags & IFF_UP &&
4530 (changes & ~(IFF_UP | IFF_PROMISC | IFF_ALLMULTI | IFF_VOLATILE)))
4531 call_netdevice_notifiers(NETDEV_CHANGE, dev);
4535 * dev_change_flags - change device settings
4537 * @flags: device state flags
4539 * Change settings on device based state flags. The flags are
4540 * in the userspace exported format.
4542 int dev_change_flags(struct net_device *dev, unsigned flags)
4545 int old_flags = dev->flags;
4547 ret = __dev_change_flags(dev, flags);
4551 changes = old_flags ^ dev->flags;
4553 rtmsg_ifinfo(RTM_NEWLINK, dev, changes);
4555 __dev_notify_flags(dev, old_flags);
4558 EXPORT_SYMBOL(dev_change_flags);
4561 * dev_set_mtu - Change maximum transfer unit
4563 * @new_mtu: new transfer unit
4565 * Change the maximum transfer size of the network device.
4567 int dev_set_mtu(struct net_device *dev, int new_mtu)
4569 const struct net_device_ops *ops = dev->netdev_ops;
4572 if (new_mtu == dev->mtu)
4575 /* MTU must be positive. */
4579 if (!netif_device_present(dev))
4583 if (ops->ndo_change_mtu)
4584 err = ops->ndo_change_mtu(dev, new_mtu);
4588 if (!err && dev->flags & IFF_UP)
4589 call_netdevice_notifiers(NETDEV_CHANGEMTU, dev);
4592 EXPORT_SYMBOL(dev_set_mtu);
4595 * dev_set_mac_address - Change Media Access Control Address
4599 * Change the hardware (MAC) address of the device
4601 int dev_set_mac_address(struct net_device *dev, struct sockaddr *sa)
4603 const struct net_device_ops *ops = dev->netdev_ops;
4606 if (!ops->ndo_set_mac_address)
4608 if (sa->sa_family != dev->type)
4610 if (!netif_device_present(dev))
4612 err = ops->ndo_set_mac_address(dev, sa);
4614 call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
4617 EXPORT_SYMBOL(dev_set_mac_address);
4620 * Perform the SIOCxIFxxx calls, inside rcu_read_lock()
4622 static int dev_ifsioc_locked(struct net *net, struct ifreq *ifr, unsigned int cmd)
4625 struct net_device *dev = dev_get_by_name_rcu(net, ifr->ifr_name);
4631 case SIOCGIFFLAGS: /* Get interface flags */
4632 ifr->ifr_flags = (short) dev_get_flags(dev);
4635 case SIOCGIFMETRIC: /* Get the metric on the interface
4636 (currently unused) */
4637 ifr->ifr_metric = 0;
4640 case SIOCGIFMTU: /* Get the MTU of a device */
4641 ifr->ifr_mtu = dev->mtu;
4646 memset(ifr->ifr_hwaddr.sa_data, 0, sizeof ifr->ifr_hwaddr.sa_data);
4648 memcpy(ifr->ifr_hwaddr.sa_data, dev->dev_addr,
4649 min(sizeof ifr->ifr_hwaddr.sa_data, (size_t) dev->addr_len));
4650 ifr->ifr_hwaddr.sa_family = dev->type;
4658 ifr->ifr_map.mem_start = dev->mem_start;
4659 ifr->ifr_map.mem_end = dev->mem_end;
4660 ifr->ifr_map.base_addr = dev->base_addr;
4661 ifr->ifr_map.irq = dev->irq;
4662 ifr->ifr_map.dma = dev->dma;
4663 ifr->ifr_map.port = dev->if_port;
4667 ifr->ifr_ifindex = dev->ifindex;
4671 ifr->ifr_qlen = dev->tx_queue_len;
4675 /* dev_ioctl() should ensure this case
4687 * Perform the SIOCxIFxxx calls, inside rtnl_lock()
4689 static int dev_ifsioc(struct net *net, struct ifreq *ifr, unsigned int cmd)
4692 struct net_device *dev = __dev_get_by_name(net, ifr->ifr_name);
4693 const struct net_device_ops *ops;
4698 ops = dev->netdev_ops;
4701 case SIOCSIFFLAGS: /* Set interface flags */
4702 return dev_change_flags(dev, ifr->ifr_flags);
4704 case SIOCSIFMETRIC: /* Set the metric on the interface
4705 (currently unused) */
4708 case SIOCSIFMTU: /* Set the MTU of a device */
4709 return dev_set_mtu(dev, ifr->ifr_mtu);
4712 return dev_set_mac_address(dev, &ifr->ifr_hwaddr);
4714 case SIOCSIFHWBROADCAST:
4715 if (ifr->ifr_hwaddr.sa_family != dev->type)
4717 memcpy(dev->broadcast, ifr->ifr_hwaddr.sa_data,
4718 min(sizeof ifr->ifr_hwaddr.sa_data, (size_t) dev->addr_len));
4719 call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
4723 if (ops->ndo_set_config) {
4724 if (!netif_device_present(dev))
4726 return ops->ndo_set_config(dev, &ifr->ifr_map);
4731 if ((!ops->ndo_set_multicast_list && !ops->ndo_set_rx_mode) ||
4732 ifr->ifr_hwaddr.sa_family != AF_UNSPEC)
4734 if (!netif_device_present(dev))
4736 return dev_mc_add_global(dev, ifr->ifr_hwaddr.sa_data);
4739 if ((!ops->ndo_set_multicast_list && !ops->ndo_set_rx_mode) ||
4740 ifr->ifr_hwaddr.sa_family != AF_UNSPEC)
4742 if (!netif_device_present(dev))
4744 return dev_mc_del_global(dev, ifr->ifr_hwaddr.sa_data);
4747 if (ifr->ifr_qlen < 0)
4749 dev->tx_queue_len = ifr->ifr_qlen;
4753 ifr->ifr_newname[IFNAMSIZ-1] = '\0';
4754 return dev_change_name(dev, ifr->ifr_newname);
4757 * Unknown or private ioctl
4760 if ((cmd >= SIOCDEVPRIVATE &&
4761 cmd <= SIOCDEVPRIVATE + 15) ||
4762 cmd == SIOCBONDENSLAVE ||
4763 cmd == SIOCBONDRELEASE ||
4764 cmd == SIOCBONDSETHWADDR ||
4765 cmd == SIOCBONDSLAVEINFOQUERY ||
4766 cmd == SIOCBONDINFOQUERY ||
4767 cmd == SIOCBONDCHANGEACTIVE ||
4768 cmd == SIOCGMIIPHY ||
4769 cmd == SIOCGMIIREG ||
4770 cmd == SIOCSMIIREG ||
4771 cmd == SIOCBRADDIF ||
4772 cmd == SIOCBRDELIF ||
4773 cmd == SIOCSHWTSTAMP ||
4774 cmd == SIOCWANDEV) {
4776 if (ops->ndo_do_ioctl) {
4777 if (netif_device_present(dev))
4778 err = ops->ndo_do_ioctl(dev, ifr, cmd);
4790 * This function handles all "interface"-type I/O control requests. The actual
4791 * 'doing' part of this is dev_ifsioc above.
4795 * dev_ioctl - network device ioctl
4796 * @net: the applicable net namespace
4797 * @cmd: command to issue
4798 * @arg: pointer to a struct ifreq in user space
4800 * Issue ioctl functions to devices. This is normally called by the
4801 * user space syscall interfaces but can sometimes be useful for
4802 * other purposes. The return value is the return from the syscall if
4803 * positive or a negative errno code on error.
4806 int dev_ioctl(struct net *net, unsigned int cmd, void __user *arg)
4812 /* One special case: SIOCGIFCONF takes ifconf argument
4813 and requires shared lock, because it sleeps writing
4817 if (cmd == SIOCGIFCONF) {
4819 ret = dev_ifconf(net, (char __user *) arg);
4823 if (cmd == SIOCGIFNAME)
4824 return dev_ifname(net, (struct ifreq __user *)arg);
4826 if (copy_from_user(&ifr, arg, sizeof(struct ifreq)))
4829 ifr.ifr_name[IFNAMSIZ-1] = 0;
4831 colon = strchr(ifr.ifr_name, ':');
4836 * See which interface the caller is talking about.
4841 * These ioctl calls:
4842 * - can be done by all.
4843 * - atomic and do not require locking.
4854 dev_load(net, ifr.ifr_name);
4856 ret = dev_ifsioc_locked(net, &ifr, cmd);
4861 if (copy_to_user(arg, &ifr,
4862 sizeof(struct ifreq)))
4868 dev_load(net, ifr.ifr_name);
4870 ret = dev_ethtool(net, &ifr);
4875 if (copy_to_user(arg, &ifr,
4876 sizeof(struct ifreq)))
4882 * These ioctl calls:
4883 * - require superuser power.
4884 * - require strict serialization.
4890 if (!capable(CAP_NET_ADMIN))
4892 dev_load(net, ifr.ifr_name);
4894 ret = dev_ifsioc(net, &ifr, cmd);
4899 if (copy_to_user(arg, &ifr,
4900 sizeof(struct ifreq)))
4906 * These ioctl calls:
4907 * - require superuser power.
4908 * - require strict serialization.
4909 * - do not return a value
4919 case SIOCSIFHWBROADCAST:
4922 case SIOCBONDENSLAVE:
4923 case SIOCBONDRELEASE:
4924 case SIOCBONDSETHWADDR:
4925 case SIOCBONDCHANGEACTIVE:
4929 if (!capable(CAP_NET_ADMIN))
4932 case SIOCBONDSLAVEINFOQUERY:
4933 case SIOCBONDINFOQUERY:
4934 dev_load(net, ifr.ifr_name);
4936 ret = dev_ifsioc(net, &ifr, cmd);
4941 /* Get the per device memory space. We can add this but
4942 * currently do not support it */
4944 /* Set the per device memory buffer space.
4945 * Not applicable in our case */
4950 * Unknown or private ioctl.
4953 if (cmd == SIOCWANDEV ||
4954 (cmd >= SIOCDEVPRIVATE &&
4955 cmd <= SIOCDEVPRIVATE + 15)) {
4956 dev_load(net, ifr.ifr_name);
4958 ret = dev_ifsioc(net, &ifr, cmd);
4960 if (!ret && copy_to_user(arg, &ifr,
4961 sizeof(struct ifreq)))
4965 /* Take care of Wireless Extensions */
4966 if (cmd >= SIOCIWFIRST && cmd <= SIOCIWLAST)
4967 return wext_handle_ioctl(net, &ifr, cmd, arg);
4974 * dev_new_index - allocate an ifindex
4975 * @net: the applicable net namespace
4977 * Returns a suitable unique value for a new device interface
4978 * number. The caller must hold the rtnl semaphore or the
4979 * dev_base_lock to be sure it remains unique.
4981 static int dev_new_index(struct net *net)
4987 if (!__dev_get_by_index(net, ifindex))
4992 /* Delayed registration/unregisteration */
4993 static LIST_HEAD(net_todo_list);
4995 static void net_set_todo(struct net_device *dev)
4997 list_add_tail(&dev->todo_list, &net_todo_list);
5000 static void rollback_registered_many(struct list_head *head)
5002 struct net_device *dev, *tmp;
5004 BUG_ON(dev_boot_phase);
5007 list_for_each_entry_safe(dev, tmp, head, unreg_list) {
5008 /* Some devices call without registering
5009 * for initialization unwind. Remove those
5010 * devices and proceed with the remaining.
5012 if (dev->reg_state == NETREG_UNINITIALIZED) {
5013 pr_debug("unregister_netdevice: device %s/%p never "
5014 "was registered\n", dev->name, dev);
5017 list_del(&dev->unreg_list);
5021 BUG_ON(dev->reg_state != NETREG_REGISTERED);
5024 /* If device is running, close it first. */
5025 dev_close_many(head);
5027 list_for_each_entry(dev, head, unreg_list) {
5028 /* And unlink it from device chain. */
5029 unlist_netdevice(dev);
5031 dev->reg_state = NETREG_UNREGISTERING;
5036 list_for_each_entry(dev, head, unreg_list) {
5037 /* Shutdown queueing discipline. */
5041 /* Notify protocols, that we are about to destroy
5042 this device. They should clean all the things.
5044 call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
5046 if (!dev->rtnl_link_ops ||
5047 dev->rtnl_link_state == RTNL_LINK_INITIALIZED)
5048 rtmsg_ifinfo(RTM_DELLINK, dev, ~0U);
5051 * Flush the unicast and multicast chains
5056 if (dev->netdev_ops->ndo_uninit)
5057 dev->netdev_ops->ndo_uninit(dev);
5059 /* Notifier chain MUST detach us from master device. */
5060 WARN_ON(dev->master);
5062 /* Remove entries from kobject tree */
5063 netdev_unregister_kobject(dev);
5066 /* Process any work delayed until the end of the batch */
5067 dev = list_first_entry(head, struct net_device, unreg_list);
5068 call_netdevice_notifiers(NETDEV_UNREGISTER_BATCH, dev);
5072 list_for_each_entry(dev, head, unreg_list)
5076 static void rollback_registered(struct net_device *dev)
5080 list_add(&dev->unreg_list, &single);
5081 rollback_registered_many(&single);
5084 unsigned long netdev_fix_features(unsigned long features, const char *name)
5086 /* Fix illegal SG+CSUM combinations. */
5087 if ((features & NETIF_F_SG) &&
5088 !(features & NETIF_F_ALL_CSUM)) {
5090 printk(KERN_NOTICE "%s: Dropping NETIF_F_SG since no "
5091 "checksum feature.\n", name);
5092 features &= ~NETIF_F_SG;
5095 /* TSO requires that SG is present as well. */
5096 if ((features & NETIF_F_TSO) && !(features & NETIF_F_SG)) {
5098 printk(KERN_NOTICE "%s: Dropping NETIF_F_TSO since no "
5099 "SG feature.\n", name);
5100 features &= ~NETIF_F_TSO;
5103 if (features & NETIF_F_UFO) {
5104 /* maybe split UFO into V4 and V6? */
5105 if (!((features & NETIF_F_GEN_CSUM) ||
5106 (features & (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))
5107 == (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))) {
5109 printk(KERN_ERR "%s: Dropping NETIF_F_UFO "
5110 "since no checksum offload features.\n",
5112 features &= ~NETIF_F_UFO;
5115 if (!(features & NETIF_F_SG)) {
5117 printk(KERN_ERR "%s: Dropping NETIF_F_UFO "
5118 "since no NETIF_F_SG feature.\n", name);
5119 features &= ~NETIF_F_UFO;
5125 EXPORT_SYMBOL(netdev_fix_features);
5128 * netif_stacked_transfer_operstate - transfer operstate
5129 * @rootdev: the root or lower level device to transfer state from
5130 * @dev: the device to transfer operstate to
5132 * Transfer operational state from root to device. This is normally
5133 * called when a stacking relationship exists between the root
5134 * device and the device(a leaf device).
5136 void netif_stacked_transfer_operstate(const struct net_device *rootdev,
5137 struct net_device *dev)
5139 if (rootdev->operstate == IF_OPER_DORMANT)
5140 netif_dormant_on(dev);
5142 netif_dormant_off(dev);
5144 if (netif_carrier_ok(rootdev)) {
5145 if (!netif_carrier_ok(dev))
5146 netif_carrier_on(dev);
5148 if (netif_carrier_ok(dev))
5149 netif_carrier_off(dev);
5152 EXPORT_SYMBOL(netif_stacked_transfer_operstate);
5155 static int netif_alloc_rx_queues(struct net_device *dev)
5157 unsigned int i, count = dev->num_rx_queues;
5158 struct netdev_rx_queue *rx;
5162 rx = kcalloc(count, sizeof(struct netdev_rx_queue), GFP_KERNEL);
5164 pr_err("netdev: Unable to allocate %u rx queues.\n", count);
5169 for (i = 0; i < count; i++)
5175 static void netdev_init_one_queue(struct net_device *dev,
5176 struct netdev_queue *queue, void *_unused)
5178 /* Initialize queue lock */
5179 spin_lock_init(&queue->_xmit_lock);
5180 netdev_set_xmit_lockdep_class(&queue->_xmit_lock, dev->type);
5181 queue->xmit_lock_owner = -1;
5182 netdev_queue_numa_node_write(queue, NUMA_NO_NODE);
5186 static int netif_alloc_netdev_queues(struct net_device *dev)
5188 unsigned int count = dev->num_tx_queues;
5189 struct netdev_queue *tx;
5193 tx = kcalloc(count, sizeof(struct netdev_queue), GFP_KERNEL);
5195 pr_err("netdev: Unable to allocate %u tx queues.\n",
5201 netdev_for_each_tx_queue(dev, netdev_init_one_queue, NULL);
5202 spin_lock_init(&dev->tx_global_lock);
5208 * register_netdevice - register a network device
5209 * @dev: device to register
5211 * Take a completed network device structure and add it to the kernel
5212 * interfaces. A %NETDEV_REGISTER message is sent to the netdev notifier
5213 * chain. 0 is returned on success. A negative errno code is returned
5214 * on a failure to set up the device, or if the name is a duplicate.
5216 * Callers must hold the rtnl semaphore. You may want
5217 * register_netdev() instead of this.
5220 * The locking appears insufficient to guarantee two parallel registers
5221 * will not get the same name.
5224 int register_netdevice(struct net_device *dev)
5227 struct net *net = dev_net(dev);
5229 BUG_ON(dev_boot_phase);
5234 /* When net_device's are persistent, this will be fatal. */
5235 BUG_ON(dev->reg_state != NETREG_UNINITIALIZED);
5238 spin_lock_init(&dev->addr_list_lock);
5239 netdev_set_addr_lockdep_class(dev);
5243 /* Init, if this function is available */
5244 if (dev->netdev_ops->ndo_init) {
5245 ret = dev->netdev_ops->ndo_init(dev);
5253 ret = dev_get_valid_name(dev, dev->name, 0);
5257 dev->ifindex = dev_new_index(net);
5258 if (dev->iflink == -1)
5259 dev->iflink = dev->ifindex;
5261 /* Fix illegal checksum combinations */
5262 if ((dev->features & NETIF_F_HW_CSUM) &&
5263 (dev->features & (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))) {
5264 printk(KERN_NOTICE "%s: mixed HW and IP checksum settings.\n",
5266 dev->features &= ~(NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM);
5269 if ((dev->features & NETIF_F_NO_CSUM) &&
5270 (dev->features & (NETIF_F_HW_CSUM|NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))) {
5271 printk(KERN_NOTICE "%s: mixed no checksumming and other settings.\n",
5273 dev->features &= ~(NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM|NETIF_F_HW_CSUM);
5276 dev->features = netdev_fix_features(dev->features, dev->name);
5278 /* Enable software GSO if SG is supported. */
5279 if (dev->features & NETIF_F_SG)
5280 dev->features |= NETIF_F_GSO;
5282 /* Enable GRO and NETIF_F_HIGHDMA for vlans by default,
5283 * vlan_dev_init() will do the dev->features check, so these features
5284 * are enabled only if supported by underlying device.
5286 dev->vlan_features |= (NETIF_F_GRO | NETIF_F_HIGHDMA);
5288 ret = call_netdevice_notifiers(NETDEV_POST_INIT, dev);
5289 ret = notifier_to_errno(ret);
5293 ret = netdev_register_kobject(dev);
5296 dev->reg_state = NETREG_REGISTERED;
5299 * Default initial state at registry is that the
5300 * device is present.
5303 set_bit(__LINK_STATE_PRESENT, &dev->state);
5305 dev_init_scheduler(dev);
5307 list_netdevice(dev);
5309 /* Notify protocols, that a new device appeared. */
5310 ret = call_netdevice_notifiers(NETDEV_REGISTER, dev);
5311 ret = notifier_to_errno(ret);
5313 rollback_registered(dev);
5314 dev->reg_state = NETREG_UNREGISTERED;
5317 * Prevent userspace races by waiting until the network
5318 * device is fully setup before sending notifications.
5320 if (!dev->rtnl_link_ops ||
5321 dev->rtnl_link_state == RTNL_LINK_INITIALIZED)
5322 rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U);
5328 if (dev->netdev_ops->ndo_uninit)
5329 dev->netdev_ops->ndo_uninit(dev);
5332 EXPORT_SYMBOL(register_netdevice);
5335 * init_dummy_netdev - init a dummy network device for NAPI
5336 * @dev: device to init
5338 * This takes a network device structure and initialize the minimum
5339 * amount of fields so it can be used to schedule NAPI polls without
5340 * registering a full blown interface. This is to be used by drivers
5341 * that need to tie several hardware interfaces to a single NAPI
5342 * poll scheduler due to HW limitations.
5344 int init_dummy_netdev(struct net_device *dev)
5346 /* Clear everything. Note we don't initialize spinlocks
5347 * are they aren't supposed to be taken by any of the
5348 * NAPI code and this dummy netdev is supposed to be
5349 * only ever used for NAPI polls
5351 memset(dev, 0, sizeof(struct net_device));
5353 /* make sure we BUG if trying to hit standard
5354 * register/unregister code path
5356 dev->reg_state = NETREG_DUMMY;
5358 /* NAPI wants this */
5359 INIT_LIST_HEAD(&dev->napi_list);
5361 /* a dummy interface is started by default */
5362 set_bit(__LINK_STATE_PRESENT, &dev->state);
5363 set_bit(__LINK_STATE_START, &dev->state);
5365 /* Note : We dont allocate pcpu_refcnt for dummy devices,
5366 * because users of this 'device' dont need to change
5372 EXPORT_SYMBOL_GPL(init_dummy_netdev);
5376 * register_netdev - register a network device
5377 * @dev: device to register
5379 * Take a completed network device structure and add it to the kernel
5380 * interfaces. A %NETDEV_REGISTER message is sent to the netdev notifier
5381 * chain. 0 is returned on success. A negative errno code is returned
5382 * on a failure to set up the device, or if the name is a duplicate.
5384 * This is a wrapper around register_netdevice that takes the rtnl semaphore
5385 * and expands the device name if you passed a format string to
5388 int register_netdev(struct net_device *dev)
5395 * If the name is a format string the caller wants us to do a
5398 if (strchr(dev->name, '%')) {
5399 err = dev_alloc_name(dev, dev->name);
5404 err = register_netdevice(dev);
5409 EXPORT_SYMBOL(register_netdev);
5411 int netdev_refcnt_read(const struct net_device *dev)
5415 for_each_possible_cpu(i)
5416 refcnt += *per_cpu_ptr(dev->pcpu_refcnt, i);
5419 EXPORT_SYMBOL(netdev_refcnt_read);
5422 * netdev_wait_allrefs - wait until all references are gone.
5424 * This is called when unregistering network devices.
5426 * Any protocol or device that holds a reference should register
5427 * for netdevice notification, and cleanup and put back the
5428 * reference if they receive an UNREGISTER event.
5429 * We can get stuck here if buggy protocols don't correctly
5432 static void netdev_wait_allrefs(struct net_device *dev)
5434 unsigned long rebroadcast_time, warning_time;
5437 linkwatch_forget_dev(dev);
5439 rebroadcast_time = warning_time = jiffies;
5440 refcnt = netdev_refcnt_read(dev);
5442 while (refcnt != 0) {
5443 if (time_after(jiffies, rebroadcast_time + 1 * HZ)) {
5446 /* Rebroadcast unregister notification */
5447 call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
5448 /* don't resend NETDEV_UNREGISTER_BATCH, _BATCH users
5449 * should have already handle it the first time */
5451 if (test_bit(__LINK_STATE_LINKWATCH_PENDING,
5453 /* We must not have linkwatch events
5454 * pending on unregister. If this
5455 * happens, we simply run the queue
5456 * unscheduled, resulting in a noop
5459 linkwatch_run_queue();
5464 rebroadcast_time = jiffies;
5469 refcnt = netdev_refcnt_read(dev);
5471 if (time_after(jiffies, warning_time + 10 * HZ)) {
5472 printk(KERN_EMERG "unregister_netdevice: "
5473 "waiting for %s to become free. Usage "
5476 warning_time = jiffies;
5485 * register_netdevice(x1);
5486 * register_netdevice(x2);
5488 * unregister_netdevice(y1);
5489 * unregister_netdevice(y2);
5495 * We are invoked by rtnl_unlock().
5496 * This allows us to deal with problems:
5497 * 1) We can delete sysfs objects which invoke hotplug
5498 * without deadlocking with linkwatch via keventd.
5499 * 2) Since we run with the RTNL semaphore not held, we can sleep
5500 * safely in order to wait for the netdev refcnt to drop to zero.
5502 * We must not return until all unregister events added during
5503 * the interval the lock was held have been completed.
5505 void netdev_run_todo(void)
5507 struct list_head list;
5509 /* Snapshot list, allow later requests */
5510 list_replace_init(&net_todo_list, &list);
5514 while (!list_empty(&list)) {
5515 struct net_device *dev
5516 = list_first_entry(&list, struct net_device, todo_list);
5517 list_del(&dev->todo_list);
5519 if (unlikely(dev->reg_state != NETREG_UNREGISTERING)) {
5520 printk(KERN_ERR "network todo '%s' but state %d\n",
5521 dev->name, dev->reg_state);
5526 dev->reg_state = NETREG_UNREGISTERED;
5528 on_each_cpu(flush_backlog, dev, 1);
5530 netdev_wait_allrefs(dev);
5533 BUG_ON(netdev_refcnt_read(dev));
5534 WARN_ON(rcu_dereference_raw(dev->ip_ptr));
5535 WARN_ON(rcu_dereference_raw(dev->ip6_ptr));
5536 WARN_ON(dev->dn_ptr);
5538 if (dev->destructor)
5539 dev->destructor(dev);
5541 /* Free network device */
5542 kobject_put(&dev->dev.kobj);
5547 * dev_txq_stats_fold - fold tx_queues stats
5548 * @dev: device to get statistics from
5549 * @stats: struct rtnl_link_stats64 to hold results
5551 void dev_txq_stats_fold(const struct net_device *dev,
5552 struct rtnl_link_stats64 *stats)
5554 u64 tx_bytes = 0, tx_packets = 0, tx_dropped = 0;
5556 struct netdev_queue *txq;
5558 for (i = 0; i < dev->num_tx_queues; i++) {
5559 txq = netdev_get_tx_queue(dev, i);
5560 spin_lock_bh(&txq->_xmit_lock);
5561 tx_bytes += txq->tx_bytes;
5562 tx_packets += txq->tx_packets;
5563 tx_dropped += txq->tx_dropped;
5564 spin_unlock_bh(&txq->_xmit_lock);
5566 if (tx_bytes || tx_packets || tx_dropped) {
5567 stats->tx_bytes = tx_bytes;
5568 stats->tx_packets = tx_packets;
5569 stats->tx_dropped = tx_dropped;
5572 EXPORT_SYMBOL(dev_txq_stats_fold);
5574 /* Convert net_device_stats to rtnl_link_stats64. They have the same
5575 * fields in the same order, with only the type differing.
5577 static void netdev_stats_to_stats64(struct rtnl_link_stats64 *stats64,
5578 const struct net_device_stats *netdev_stats)
5580 #if BITS_PER_LONG == 64
5581 BUILD_BUG_ON(sizeof(*stats64) != sizeof(*netdev_stats));
5582 memcpy(stats64, netdev_stats, sizeof(*stats64));
5584 size_t i, n = sizeof(*stats64) / sizeof(u64);
5585 const unsigned long *src = (const unsigned long *)netdev_stats;
5586 u64 *dst = (u64 *)stats64;
5588 BUILD_BUG_ON(sizeof(*netdev_stats) / sizeof(unsigned long) !=
5589 sizeof(*stats64) / sizeof(u64));
5590 for (i = 0; i < n; i++)
5596 * dev_get_stats - get network device statistics
5597 * @dev: device to get statistics from
5598 * @storage: place to store stats
5600 * Get network statistics from device. Return @storage.
5601 * The device driver may provide its own method by setting
5602 * dev->netdev_ops->get_stats64 or dev->netdev_ops->get_stats;
5603 * otherwise the internal statistics structure is used.
5605 struct rtnl_link_stats64 *dev_get_stats(struct net_device *dev,
5606 struct rtnl_link_stats64 *storage)
5608 const struct net_device_ops *ops = dev->netdev_ops;
5610 if (ops->ndo_get_stats64) {
5611 memset(storage, 0, sizeof(*storage));
5612 ops->ndo_get_stats64(dev, storage);
5613 } else if (ops->ndo_get_stats) {
5614 netdev_stats_to_stats64(storage, ops->ndo_get_stats(dev));
5616 netdev_stats_to_stats64(storage, &dev->stats);
5617 dev_txq_stats_fold(dev, storage);
5619 storage->rx_dropped += atomic_long_read(&dev->rx_dropped);
5622 EXPORT_SYMBOL(dev_get_stats);
5624 struct netdev_queue *dev_ingress_queue_create(struct net_device *dev)
5626 struct netdev_queue *queue = dev_ingress_queue(dev);
5628 #ifdef CONFIG_NET_CLS_ACT
5631 queue = kzalloc(sizeof(*queue), GFP_KERNEL);
5634 netdev_init_one_queue(dev, queue, NULL);
5635 queue->qdisc = &noop_qdisc;
5636 queue->qdisc_sleeping = &noop_qdisc;
5637 rcu_assign_pointer(dev->ingress_queue, queue);
5643 * alloc_netdev_mq - allocate network device
5644 * @sizeof_priv: size of private data to allocate space for
5645 * @name: device name format string
5646 * @setup: callback to initialize device
5647 * @queue_count: the number of subqueues to allocate
5649 * Allocates a struct net_device with private data area for driver use
5650 * and performs basic initialization. Also allocates subquue structs
5651 * for each queue on the device at the end of the netdevice.
5653 struct net_device *alloc_netdev_mq(int sizeof_priv, const char *name,
5654 void (*setup)(struct net_device *), unsigned int queue_count)
5656 struct net_device *dev;
5658 struct net_device *p;
5660 BUG_ON(strlen(name) >= sizeof(dev->name));
5662 if (queue_count < 1) {
5663 pr_err("alloc_netdev: Unable to allocate device "
5664 "with zero queues.\n");
5668 alloc_size = sizeof(struct net_device);
5670 /* ensure 32-byte alignment of private area */
5671 alloc_size = ALIGN(alloc_size, NETDEV_ALIGN);
5672 alloc_size += sizeof_priv;
5674 /* ensure 32-byte alignment of whole construct */
5675 alloc_size += NETDEV_ALIGN - 1;
5677 p = kzalloc(alloc_size, GFP_KERNEL);
5679 printk(KERN_ERR "alloc_netdev: Unable to allocate device.\n");
5683 dev = PTR_ALIGN(p, NETDEV_ALIGN);
5684 dev->padded = (char *)dev - (char *)p;
5686 dev->pcpu_refcnt = alloc_percpu(int);
5687 if (!dev->pcpu_refcnt)
5690 if (dev_addr_init(dev))
5696 dev_net_set(dev, &init_net);
5698 dev->num_tx_queues = queue_count;
5699 dev->real_num_tx_queues = queue_count;
5700 if (netif_alloc_netdev_queues(dev))
5704 dev->num_rx_queues = queue_count;
5705 dev->real_num_rx_queues = queue_count;
5706 if (netif_alloc_rx_queues(dev))
5710 dev->gso_max_size = GSO_MAX_SIZE;
5712 INIT_LIST_HEAD(&dev->ethtool_ntuple_list.list);
5713 dev->ethtool_ntuple_list.count = 0;
5714 INIT_LIST_HEAD(&dev->napi_list);
5715 INIT_LIST_HEAD(&dev->unreg_list);
5716 INIT_LIST_HEAD(&dev->link_watch_list);
5717 dev->priv_flags = IFF_XMIT_DST_RELEASE;
5719 strcpy(dev->name, name);
5723 free_percpu(dev->pcpu_refcnt);
5733 EXPORT_SYMBOL(alloc_netdev_mq);
5736 * free_netdev - free network device
5739 * This function does the last stage of destroying an allocated device
5740 * interface. The reference to the device object is released.
5741 * If this is the last reference then it will be freed.
5743 void free_netdev(struct net_device *dev)
5745 struct napi_struct *p, *n;
5747 release_net(dev_net(dev));
5754 kfree(rcu_dereference_raw(dev->ingress_queue));
5756 /* Flush device addresses */
5757 dev_addr_flush(dev);
5759 /* Clear ethtool n-tuple list */
5760 ethtool_ntuple_flush(dev);
5762 list_for_each_entry_safe(p, n, &dev->napi_list, dev_list)
5765 free_percpu(dev->pcpu_refcnt);
5766 dev->pcpu_refcnt = NULL;
5768 /* Compatibility with error handling in drivers */
5769 if (dev->reg_state == NETREG_UNINITIALIZED) {
5770 kfree((char *)dev - dev->padded);
5774 BUG_ON(dev->reg_state != NETREG_UNREGISTERED);
5775 dev->reg_state = NETREG_RELEASED;
5777 /* will free via device release */
5778 put_device(&dev->dev);
5780 EXPORT_SYMBOL(free_netdev);
5783 * synchronize_net - Synchronize with packet receive processing
5785 * Wait for packets currently being received to be done.
5786 * Does not block later packets from starting.
5788 void synchronize_net(void)
5793 EXPORT_SYMBOL(synchronize_net);
5796 * unregister_netdevice_queue - remove device from the kernel
5800 * This function shuts down a device interface and removes it
5801 * from the kernel tables.
5802 * If head not NULL, device is queued to be unregistered later.
5804 * Callers must hold the rtnl semaphore. You may want
5805 * unregister_netdev() instead of this.
5808 void unregister_netdevice_queue(struct net_device *dev, struct list_head *head)
5813 list_move_tail(&dev->unreg_list, head);
5815 rollback_registered(dev);
5816 /* Finish processing unregister after unlock */
5820 EXPORT_SYMBOL(unregister_netdevice_queue);
5823 * unregister_netdevice_many - unregister many devices
5824 * @head: list of devices
5826 void unregister_netdevice_many(struct list_head *head)
5828 struct net_device *dev;
5830 if (!list_empty(head)) {
5831 rollback_registered_many(head);
5832 list_for_each_entry(dev, head, unreg_list)
5836 EXPORT_SYMBOL(unregister_netdevice_many);
5839 * unregister_netdev - remove device from the kernel
5842 * This function shuts down a device interface and removes it
5843 * from the kernel tables.
5845 * This is just a wrapper for unregister_netdevice that takes
5846 * the rtnl semaphore. In general you want to use this and not
5847 * unregister_netdevice.
5849 void unregister_netdev(struct net_device *dev)
5852 unregister_netdevice(dev);
5855 EXPORT_SYMBOL(unregister_netdev);
5858 * dev_change_net_namespace - move device to different nethost namespace
5860 * @net: network namespace
5861 * @pat: If not NULL name pattern to try if the current device name
5862 * is already taken in the destination network namespace.
5864 * This function shuts down a device interface and moves it
5865 * to a new network namespace. On success 0 is returned, on
5866 * a failure a netagive errno code is returned.
5868 * Callers must hold the rtnl semaphore.
5871 int dev_change_net_namespace(struct net_device *dev, struct net *net, const char *pat)
5877 /* Don't allow namespace local devices to be moved. */
5879 if (dev->features & NETIF_F_NETNS_LOCAL)
5882 /* Ensure the device has been registrered */
5884 if (dev->reg_state != NETREG_REGISTERED)
5887 /* Get out if there is nothing todo */
5889 if (net_eq(dev_net(dev), net))
5892 /* Pick the destination device name, and ensure
5893 * we can use it in the destination network namespace.
5896 if (__dev_get_by_name(net, dev->name)) {
5897 /* We get here if we can't use the current device name */
5900 if (dev_get_valid_name(dev, pat, 1))
5905 * And now a mini version of register_netdevice unregister_netdevice.
5908 /* If device is running close it first. */
5911 /* And unlink it from device chain */
5913 unlist_netdevice(dev);
5917 /* Shutdown queueing discipline. */
5920 /* Notify protocols, that we are about to destroy
5921 this device. They should clean all the things.
5923 Note that dev->reg_state stays at NETREG_REGISTERED.
5924 This is wanted because this way 8021q and macvlan know
5925 the device is just moving and can keep their slaves up.
5927 call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
5928 call_netdevice_notifiers(NETDEV_UNREGISTER_BATCH, dev);
5931 * Flush the unicast and multicast chains
5936 /* Actually switch the network namespace */
5937 dev_net_set(dev, net);
5939 /* If there is an ifindex conflict assign a new one */
5940 if (__dev_get_by_index(net, dev->ifindex)) {
5941 int iflink = (dev->iflink == dev->ifindex);
5942 dev->ifindex = dev_new_index(net);
5944 dev->iflink = dev->ifindex;
5947 /* Fixup kobjects */
5948 err = device_rename(&dev->dev, dev->name);
5951 /* Add the device back in the hashes */
5952 list_netdevice(dev);
5954 /* Notify protocols, that a new device appeared. */
5955 call_netdevice_notifiers(NETDEV_REGISTER, dev);
5958 * Prevent userspace races by waiting until the network
5959 * device is fully setup before sending notifications.
5961 rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U);
5968 EXPORT_SYMBOL_GPL(dev_change_net_namespace);
5970 static int dev_cpu_callback(struct notifier_block *nfb,
5971 unsigned long action,
5974 struct sk_buff **list_skb;
5975 struct sk_buff *skb;
5976 unsigned int cpu, oldcpu = (unsigned long)ocpu;
5977 struct softnet_data *sd, *oldsd;
5979 if (action != CPU_DEAD && action != CPU_DEAD_FROZEN)
5982 local_irq_disable();
5983 cpu = smp_processor_id();
5984 sd = &per_cpu(softnet_data, cpu);
5985 oldsd = &per_cpu(softnet_data, oldcpu);
5987 /* Find end of our completion_queue. */
5988 list_skb = &sd->completion_queue;
5990 list_skb = &(*list_skb)->next;
5991 /* Append completion queue from offline CPU. */
5992 *list_skb = oldsd->completion_queue;
5993 oldsd->completion_queue = NULL;
5995 /* Append output queue from offline CPU. */
5996 if (oldsd->output_queue) {
5997 *sd->output_queue_tailp = oldsd->output_queue;
5998 sd->output_queue_tailp = oldsd->output_queue_tailp;
5999 oldsd->output_queue = NULL;
6000 oldsd->output_queue_tailp = &oldsd->output_queue;
6003 raise_softirq_irqoff(NET_TX_SOFTIRQ);
6006 /* Process offline CPU's input_pkt_queue */
6007 while ((skb = __skb_dequeue(&oldsd->process_queue))) {
6009 input_queue_head_incr(oldsd);
6011 while ((skb = __skb_dequeue(&oldsd->input_pkt_queue))) {
6013 input_queue_head_incr(oldsd);
6021 * netdev_increment_features - increment feature set by one
6022 * @all: current feature set
6023 * @one: new feature set
6024 * @mask: mask feature set
6026 * Computes a new feature set after adding a device with feature set
6027 * @one to the master device with current feature set @all. Will not
6028 * enable anything that is off in @mask. Returns the new feature set.
6030 unsigned long netdev_increment_features(unsigned long all, unsigned long one,
6033 /* If device needs checksumming, downgrade to it. */
6034 if (all & NETIF_F_NO_CSUM && !(one & NETIF_F_NO_CSUM))
6035 all ^= NETIF_F_NO_CSUM | (one & NETIF_F_ALL_CSUM);
6036 else if (mask & NETIF_F_ALL_CSUM) {
6037 /* If one device supports v4/v6 checksumming, set for all. */
6038 if (one & (NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM) &&
6039 !(all & NETIF_F_GEN_CSUM)) {
6040 all &= ~NETIF_F_ALL_CSUM;
6041 all |= one & (NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM);
6044 /* If one device supports hw checksumming, set for all. */
6045 if (one & NETIF_F_GEN_CSUM && !(all & NETIF_F_GEN_CSUM)) {
6046 all &= ~NETIF_F_ALL_CSUM;
6047 all |= NETIF_F_HW_CSUM;
6051 one |= NETIF_F_ALL_CSUM;
6053 one |= all & NETIF_F_ONE_FOR_ALL;
6054 all &= one | NETIF_F_LLTX | NETIF_F_GSO | NETIF_F_UFO;
6055 all |= one & mask & NETIF_F_ONE_FOR_ALL;
6059 EXPORT_SYMBOL(netdev_increment_features);
6061 static struct hlist_head *netdev_create_hash(void)
6064 struct hlist_head *hash;
6066 hash = kmalloc(sizeof(*hash) * NETDEV_HASHENTRIES, GFP_KERNEL);
6068 for (i = 0; i < NETDEV_HASHENTRIES; i++)
6069 INIT_HLIST_HEAD(&hash[i]);
6074 /* Initialize per network namespace state */
6075 static int __net_init netdev_init(struct net *net)
6077 INIT_LIST_HEAD(&net->dev_base_head);
6079 net->dev_name_head = netdev_create_hash();
6080 if (net->dev_name_head == NULL)
6083 net->dev_index_head = netdev_create_hash();
6084 if (net->dev_index_head == NULL)
6090 kfree(net->dev_name_head);
6096 * netdev_drivername - network driver for the device
6097 * @dev: network device
6098 * @buffer: buffer for resulting name
6099 * @len: size of buffer
6101 * Determine network driver for device.
6103 char *netdev_drivername(const struct net_device *dev, char *buffer, int len)
6105 const struct device_driver *driver;
6106 const struct device *parent;
6108 if (len <= 0 || !buffer)
6112 parent = dev->dev.parent;
6117 driver = parent->driver;
6118 if (driver && driver->name)
6119 strlcpy(buffer, driver->name, len);
6123 static int __netdev_printk(const char *level, const struct net_device *dev,
6124 struct va_format *vaf)
6128 if (dev && dev->dev.parent)
6129 r = dev_printk(level, dev->dev.parent, "%s: %pV",
6130 netdev_name(dev), vaf);
6132 r = printk("%s%s: %pV", level, netdev_name(dev), vaf);
6134 r = printk("%s(NULL net_device): %pV", level, vaf);
6139 int netdev_printk(const char *level, const struct net_device *dev,
6140 const char *format, ...)
6142 struct va_format vaf;
6146 va_start(args, format);
6151 r = __netdev_printk(level, dev, &vaf);
6156 EXPORT_SYMBOL(netdev_printk);
6158 #define define_netdev_printk_level(func, level) \
6159 int func(const struct net_device *dev, const char *fmt, ...) \
6162 struct va_format vaf; \
6165 va_start(args, fmt); \
6170 r = __netdev_printk(level, dev, &vaf); \
6175 EXPORT_SYMBOL(func);
6177 define_netdev_printk_level(netdev_emerg, KERN_EMERG);
6178 define_netdev_printk_level(netdev_alert, KERN_ALERT);
6179 define_netdev_printk_level(netdev_crit, KERN_CRIT);
6180 define_netdev_printk_level(netdev_err, KERN_ERR);
6181 define_netdev_printk_level(netdev_warn, KERN_WARNING);
6182 define_netdev_printk_level(netdev_notice, KERN_NOTICE);
6183 define_netdev_printk_level(netdev_info, KERN_INFO);
6185 static void __net_exit netdev_exit(struct net *net)
6187 kfree(net->dev_name_head);
6188 kfree(net->dev_index_head);
6191 static struct pernet_operations __net_initdata netdev_net_ops = {
6192 .init = netdev_init,
6193 .exit = netdev_exit,
6196 static void __net_exit default_device_exit(struct net *net)
6198 struct net_device *dev, *aux;
6200 * Push all migratable network devices back to the
6201 * initial network namespace
6204 for_each_netdev_safe(net, dev, aux) {
6206 char fb_name[IFNAMSIZ];
6208 /* Ignore unmoveable devices (i.e. loopback) */
6209 if (dev->features & NETIF_F_NETNS_LOCAL)
6212 /* Leave virtual devices for the generic cleanup */
6213 if (dev->rtnl_link_ops)
6216 /* Push remaing network devices to init_net */
6217 snprintf(fb_name, IFNAMSIZ, "dev%d", dev->ifindex);
6218 err = dev_change_net_namespace(dev, &init_net, fb_name);
6220 printk(KERN_EMERG "%s: failed to move %s to init_net: %d\n",
6221 __func__, dev->name, err);
6228 static void __net_exit default_device_exit_batch(struct list_head *net_list)
6230 /* At exit all network devices most be removed from a network
6231 * namespace. Do this in the reverse order of registeration.
6232 * Do this across as many network namespaces as possible to
6233 * improve batching efficiency.
6235 struct net_device *dev;
6237 LIST_HEAD(dev_kill_list);
6240 list_for_each_entry(net, net_list, exit_list) {
6241 for_each_netdev_reverse(net, dev) {
6242 if (dev->rtnl_link_ops)
6243 dev->rtnl_link_ops->dellink(dev, &dev_kill_list);
6245 unregister_netdevice_queue(dev, &dev_kill_list);
6248 unregister_netdevice_many(&dev_kill_list);
6252 static struct pernet_operations __net_initdata default_device_ops = {
6253 .exit = default_device_exit,
6254 .exit_batch = default_device_exit_batch,
6258 * Initialize the DEV module. At boot time this walks the device list and
6259 * unhooks any devices that fail to initialise (normally hardware not
6260 * present) and leaves us with a valid list of present and active devices.
6265 * This is called single threaded during boot, so no need
6266 * to take the rtnl semaphore.
6268 static int __init net_dev_init(void)
6270 int i, rc = -ENOMEM;
6272 BUG_ON(!dev_boot_phase);
6274 if (dev_proc_init())
6277 if (netdev_kobject_init())
6280 INIT_LIST_HEAD(&ptype_all);
6281 for (i = 0; i < PTYPE_HASH_SIZE; i++)
6282 INIT_LIST_HEAD(&ptype_base[i]);
6284 if (register_pernet_subsys(&netdev_net_ops))
6288 * Initialise the packet receive queues.
6291 for_each_possible_cpu(i) {
6292 struct softnet_data *sd = &per_cpu(softnet_data, i);
6294 memset(sd, 0, sizeof(*sd));
6295 skb_queue_head_init(&sd->input_pkt_queue);
6296 skb_queue_head_init(&sd->process_queue);
6297 sd->completion_queue = NULL;
6298 INIT_LIST_HEAD(&sd->poll_list);
6299 sd->output_queue = NULL;
6300 sd->output_queue_tailp = &sd->output_queue;
6302 sd->csd.func = rps_trigger_softirq;
6308 sd->backlog.poll = process_backlog;
6309 sd->backlog.weight = weight_p;
6310 sd->backlog.gro_list = NULL;
6311 sd->backlog.gro_count = 0;
6316 /* The loopback device is special if any other network devices
6317 * is present in a network namespace the loopback device must
6318 * be present. Since we now dynamically allocate and free the
6319 * loopback device ensure this invariant is maintained by
6320 * keeping the loopback device as the first device on the
6321 * list of network devices. Ensuring the loopback devices
6322 * is the first device that appears and the last network device
6325 if (register_pernet_device(&loopback_net_ops))
6328 if (register_pernet_device(&default_device_ops))
6331 open_softirq(NET_TX_SOFTIRQ, net_tx_action);
6332 open_softirq(NET_RX_SOFTIRQ, net_rx_action);
6334 hotcpu_notifier(dev_cpu_callback, 0);
6342 subsys_initcall(net_dev_init);
6344 static int __init initialize_hashrnd(void)
6346 get_random_bytes(&hashrnd, sizeof(hashrnd));
6350 late_initcall_sync(initialize_hashrnd);