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 <linux/bitops.h>
77 #include <linux/capability.h>
78 #include <linux/cpu.h>
79 #include <linux/types.h>
80 #include <linux/kernel.h>
81 #include <linux/hash.h>
82 #include <linux/slab.h>
83 #include <linux/sched.h>
84 #include <linux/mutex.h>
85 #include <linux/string.h>
87 #include <linux/socket.h>
88 #include <linux/sockios.h>
89 #include <linux/errno.h>
90 #include <linux/interrupt.h>
91 #include <linux/if_ether.h>
92 #include <linux/netdevice.h>
93 #include <linux/etherdevice.h>
94 #include <linux/ethtool.h>
95 #include <linux/notifier.h>
96 #include <linux/skbuff.h>
97 #include <net/net_namespace.h>
99 #include <linux/rtnetlink.h>
100 #include <linux/stat.h>
102 #include <net/pkt_sched.h>
103 #include <net/checksum.h>
104 #include <net/xfrm.h>
105 #include <linux/highmem.h>
106 #include <linux/init.h>
107 #include <linux/module.h>
108 #include <linux/netpoll.h>
109 #include <linux/rcupdate.h>
110 #include <linux/delay.h>
111 #include <net/iw_handler.h>
112 #include <asm/current.h>
113 #include <linux/audit.h>
114 #include <linux/dmaengine.h>
115 #include <linux/err.h>
116 #include <linux/ctype.h>
117 #include <linux/if_arp.h>
118 #include <linux/if_vlan.h>
119 #include <linux/ip.h>
121 #include <linux/ipv6.h>
122 #include <linux/in.h>
123 #include <linux/jhash.h>
124 #include <linux/random.h>
125 #include <trace/events/napi.h>
126 #include <trace/events/net.h>
127 #include <trace/events/skb.h>
128 #include <linux/pci.h>
129 #include <linux/inetdevice.h>
130 #include <linux/cpu_rmap.h>
131 #include <linux/static_key.h>
132 #include <linux/hashtable.h>
133 #include <linux/vmalloc.h>
134 #include <linux/if_macvlan.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)
144 static DEFINE_SPINLOCK(ptype_lock);
145 static DEFINE_SPINLOCK(offload_lock);
146 struct list_head ptype_base[PTYPE_HASH_SIZE] __read_mostly;
147 struct list_head ptype_all __read_mostly; /* Taps */
148 static struct list_head offload_base __read_mostly;
151 * The @dev_base_head list is protected by @dev_base_lock and the rtnl
154 * Pure readers hold dev_base_lock for reading, or rcu_read_lock()
156 * Writers must hold the rtnl semaphore while they loop through the
157 * dev_base_head list, and hold dev_base_lock for writing when they do the
158 * actual updates. This allows pure readers to access the list even
159 * while a writer is preparing to update it.
161 * To put it another way, dev_base_lock is held for writing only to
162 * protect against pure readers; the rtnl semaphore provides the
163 * protection against other writers.
165 * See, for example usages, register_netdevice() and
166 * unregister_netdevice(), which must be called with the rtnl
169 DEFINE_RWLOCK(dev_base_lock);
170 EXPORT_SYMBOL(dev_base_lock);
172 /* protects napi_hash addition/deletion and napi_gen_id */
173 static DEFINE_SPINLOCK(napi_hash_lock);
175 static unsigned int napi_gen_id;
176 static DEFINE_HASHTABLE(napi_hash, 8);
178 static seqcount_t devnet_rename_seq;
180 static inline void dev_base_seq_inc(struct net *net)
182 while (++net->dev_base_seq == 0);
185 static inline struct hlist_head *dev_name_hash(struct net *net, const char *name)
187 unsigned int hash = full_name_hash(name, strnlen(name, IFNAMSIZ));
189 return &net->dev_name_head[hash_32(hash, NETDEV_HASHBITS)];
192 static inline struct hlist_head *dev_index_hash(struct net *net, int ifindex)
194 return &net->dev_index_head[ifindex & (NETDEV_HASHENTRIES - 1)];
197 static inline void rps_lock(struct softnet_data *sd)
200 spin_lock(&sd->input_pkt_queue.lock);
204 static inline void rps_unlock(struct softnet_data *sd)
207 spin_unlock(&sd->input_pkt_queue.lock);
211 /* Device list insertion */
212 static void list_netdevice(struct net_device *dev)
214 struct net *net = dev_net(dev);
218 write_lock_bh(&dev_base_lock);
219 list_add_tail_rcu(&dev->dev_list, &net->dev_base_head);
220 hlist_add_head_rcu(&dev->name_hlist, dev_name_hash(net, dev->name));
221 hlist_add_head_rcu(&dev->index_hlist,
222 dev_index_hash(net, dev->ifindex));
223 write_unlock_bh(&dev_base_lock);
225 dev_base_seq_inc(net);
228 /* Device list removal
229 * caller must respect a RCU grace period before freeing/reusing dev
231 static void unlist_netdevice(struct net_device *dev)
235 /* Unlink dev from the device chain */
236 write_lock_bh(&dev_base_lock);
237 list_del_rcu(&dev->dev_list);
238 hlist_del_rcu(&dev->name_hlist);
239 hlist_del_rcu(&dev->index_hlist);
240 write_unlock_bh(&dev_base_lock);
242 dev_base_seq_inc(dev_net(dev));
249 static RAW_NOTIFIER_HEAD(netdev_chain);
252 * Device drivers call our routines to queue packets here. We empty the
253 * queue in the local softnet handler.
256 DEFINE_PER_CPU_ALIGNED(struct softnet_data, softnet_data);
257 EXPORT_PER_CPU_SYMBOL(softnet_data);
259 #ifdef CONFIG_LOCKDEP
261 * register_netdevice() inits txq->_xmit_lock and sets lockdep class
262 * according to dev->type
264 static const unsigned short netdev_lock_type[] =
265 {ARPHRD_NETROM, ARPHRD_ETHER, ARPHRD_EETHER, ARPHRD_AX25,
266 ARPHRD_PRONET, ARPHRD_CHAOS, ARPHRD_IEEE802, ARPHRD_ARCNET,
267 ARPHRD_APPLETLK, ARPHRD_DLCI, ARPHRD_ATM, ARPHRD_METRICOM,
268 ARPHRD_IEEE1394, ARPHRD_EUI64, ARPHRD_INFINIBAND, ARPHRD_SLIP,
269 ARPHRD_CSLIP, ARPHRD_SLIP6, ARPHRD_CSLIP6, ARPHRD_RSRVD,
270 ARPHRD_ADAPT, ARPHRD_ROSE, ARPHRD_X25, ARPHRD_HWX25,
271 ARPHRD_PPP, ARPHRD_CISCO, ARPHRD_LAPB, ARPHRD_DDCMP,
272 ARPHRD_RAWHDLC, ARPHRD_TUNNEL, ARPHRD_TUNNEL6, ARPHRD_FRAD,
273 ARPHRD_SKIP, ARPHRD_LOOPBACK, ARPHRD_LOCALTLK, ARPHRD_FDDI,
274 ARPHRD_BIF, ARPHRD_SIT, ARPHRD_IPDDP, ARPHRD_IPGRE,
275 ARPHRD_PIMREG, ARPHRD_HIPPI, ARPHRD_ASH, ARPHRD_ECONET,
276 ARPHRD_IRDA, ARPHRD_FCPP, ARPHRD_FCAL, ARPHRD_FCPL,
277 ARPHRD_FCFABRIC, ARPHRD_IEEE80211, ARPHRD_IEEE80211_PRISM,
278 ARPHRD_IEEE80211_RADIOTAP, ARPHRD_PHONET, ARPHRD_PHONET_PIPE,
279 ARPHRD_IEEE802154, ARPHRD_VOID, ARPHRD_NONE};
281 static const char *const netdev_lock_name[] =
282 {"_xmit_NETROM", "_xmit_ETHER", "_xmit_EETHER", "_xmit_AX25",
283 "_xmit_PRONET", "_xmit_CHAOS", "_xmit_IEEE802", "_xmit_ARCNET",
284 "_xmit_APPLETLK", "_xmit_DLCI", "_xmit_ATM", "_xmit_METRICOM",
285 "_xmit_IEEE1394", "_xmit_EUI64", "_xmit_INFINIBAND", "_xmit_SLIP",
286 "_xmit_CSLIP", "_xmit_SLIP6", "_xmit_CSLIP6", "_xmit_RSRVD",
287 "_xmit_ADAPT", "_xmit_ROSE", "_xmit_X25", "_xmit_HWX25",
288 "_xmit_PPP", "_xmit_CISCO", "_xmit_LAPB", "_xmit_DDCMP",
289 "_xmit_RAWHDLC", "_xmit_TUNNEL", "_xmit_TUNNEL6", "_xmit_FRAD",
290 "_xmit_SKIP", "_xmit_LOOPBACK", "_xmit_LOCALTLK", "_xmit_FDDI",
291 "_xmit_BIF", "_xmit_SIT", "_xmit_IPDDP", "_xmit_IPGRE",
292 "_xmit_PIMREG", "_xmit_HIPPI", "_xmit_ASH", "_xmit_ECONET",
293 "_xmit_IRDA", "_xmit_FCPP", "_xmit_FCAL", "_xmit_FCPL",
294 "_xmit_FCFABRIC", "_xmit_IEEE80211", "_xmit_IEEE80211_PRISM",
295 "_xmit_IEEE80211_RADIOTAP", "_xmit_PHONET", "_xmit_PHONET_PIPE",
296 "_xmit_IEEE802154", "_xmit_VOID", "_xmit_NONE"};
298 static struct lock_class_key netdev_xmit_lock_key[ARRAY_SIZE(netdev_lock_type)];
299 static struct lock_class_key netdev_addr_lock_key[ARRAY_SIZE(netdev_lock_type)];
301 static inline unsigned short netdev_lock_pos(unsigned short dev_type)
305 for (i = 0; i < ARRAY_SIZE(netdev_lock_type); i++)
306 if (netdev_lock_type[i] == dev_type)
308 /* the last key is used by default */
309 return ARRAY_SIZE(netdev_lock_type) - 1;
312 static inline void netdev_set_xmit_lockdep_class(spinlock_t *lock,
313 unsigned short dev_type)
317 i = netdev_lock_pos(dev_type);
318 lockdep_set_class_and_name(lock, &netdev_xmit_lock_key[i],
319 netdev_lock_name[i]);
322 static inline void netdev_set_addr_lockdep_class(struct net_device *dev)
326 i = netdev_lock_pos(dev->type);
327 lockdep_set_class_and_name(&dev->addr_list_lock,
328 &netdev_addr_lock_key[i],
329 netdev_lock_name[i]);
332 static inline void netdev_set_xmit_lockdep_class(spinlock_t *lock,
333 unsigned short dev_type)
336 static inline void netdev_set_addr_lockdep_class(struct net_device *dev)
341 /*******************************************************************************
343 Protocol management and registration routines
345 *******************************************************************************/
348 * Add a protocol ID to the list. Now that the input handler is
349 * smarter we can dispense with all the messy stuff that used to be
352 * BEWARE!!! Protocol handlers, mangling input packets,
353 * MUST BE last in hash buckets and checking protocol handlers
354 * MUST start from promiscuous ptype_all chain in net_bh.
355 * It is true now, do not change it.
356 * Explanation follows: if protocol handler, mangling packet, will
357 * be the first on list, it is not able to sense, that packet
358 * is cloned and should be copied-on-write, so that it will
359 * change it and subsequent readers will get broken packet.
363 static inline struct list_head *ptype_head(const struct packet_type *pt)
365 if (pt->type == htons(ETH_P_ALL))
368 return &ptype_base[ntohs(pt->type) & PTYPE_HASH_MASK];
372 * dev_add_pack - add packet handler
373 * @pt: packet type declaration
375 * Add a protocol handler to the networking stack. The passed &packet_type
376 * is linked into kernel lists and may not be freed until it has been
377 * removed from the kernel lists.
379 * This call does not sleep therefore it can not
380 * guarantee all CPU's that are in middle of receiving packets
381 * will see the new packet type (until the next received packet).
384 void dev_add_pack(struct packet_type *pt)
386 struct list_head *head = ptype_head(pt);
388 spin_lock(&ptype_lock);
389 list_add_rcu(&pt->list, head);
390 spin_unlock(&ptype_lock);
392 EXPORT_SYMBOL(dev_add_pack);
395 * __dev_remove_pack - remove packet handler
396 * @pt: packet type declaration
398 * Remove a protocol handler that was previously added to the kernel
399 * protocol handlers by dev_add_pack(). The passed &packet_type is removed
400 * from the kernel lists and can be freed or reused once this function
403 * The packet type might still be in use by receivers
404 * and must not be freed until after all the CPU's have gone
405 * through a quiescent state.
407 void __dev_remove_pack(struct packet_type *pt)
409 struct list_head *head = ptype_head(pt);
410 struct packet_type *pt1;
412 spin_lock(&ptype_lock);
414 list_for_each_entry(pt1, head, list) {
416 list_del_rcu(&pt->list);
421 pr_warn("dev_remove_pack: %p not found\n", pt);
423 spin_unlock(&ptype_lock);
425 EXPORT_SYMBOL(__dev_remove_pack);
428 * dev_remove_pack - remove packet handler
429 * @pt: packet type declaration
431 * Remove a protocol handler that was previously added to the kernel
432 * protocol handlers by dev_add_pack(). The passed &packet_type is removed
433 * from the kernel lists and can be freed or reused once this function
436 * This call sleeps to guarantee that no CPU is looking at the packet
439 void dev_remove_pack(struct packet_type *pt)
441 __dev_remove_pack(pt);
445 EXPORT_SYMBOL(dev_remove_pack);
449 * dev_add_offload - register offload handlers
450 * @po: protocol offload declaration
452 * Add protocol offload handlers to the networking stack. The passed
453 * &proto_offload is linked into kernel lists and may not be freed until
454 * it has been removed from the kernel lists.
456 * This call does not sleep therefore it can not
457 * guarantee all CPU's that are in middle of receiving packets
458 * will see the new offload handlers (until the next received packet).
460 void dev_add_offload(struct packet_offload *po)
462 struct list_head *head = &offload_base;
464 spin_lock(&offload_lock);
465 list_add_rcu(&po->list, head);
466 spin_unlock(&offload_lock);
468 EXPORT_SYMBOL(dev_add_offload);
471 * __dev_remove_offload - remove offload handler
472 * @po: packet offload declaration
474 * Remove a protocol offload handler that was previously added to the
475 * kernel offload handlers by dev_add_offload(). The passed &offload_type
476 * is removed from the kernel lists and can be freed or reused once this
479 * The packet type might still be in use by receivers
480 * and must not be freed until after all the CPU's have gone
481 * through a quiescent state.
483 void __dev_remove_offload(struct packet_offload *po)
485 struct list_head *head = &offload_base;
486 struct packet_offload *po1;
488 spin_lock(&offload_lock);
490 list_for_each_entry(po1, head, list) {
492 list_del_rcu(&po->list);
497 pr_warn("dev_remove_offload: %p not found\n", po);
499 spin_unlock(&offload_lock);
501 EXPORT_SYMBOL(__dev_remove_offload);
504 * dev_remove_offload - remove packet offload handler
505 * @po: packet offload declaration
507 * Remove a packet offload handler that was previously added to the kernel
508 * offload handlers by dev_add_offload(). The passed &offload_type is
509 * removed from the kernel lists and can be freed or reused once this
512 * This call sleeps to guarantee that no CPU is looking at the packet
515 void dev_remove_offload(struct packet_offload *po)
517 __dev_remove_offload(po);
521 EXPORT_SYMBOL(dev_remove_offload);
523 /******************************************************************************
525 Device Boot-time Settings Routines
527 *******************************************************************************/
529 /* Boot time configuration table */
530 static struct netdev_boot_setup dev_boot_setup[NETDEV_BOOT_SETUP_MAX];
533 * netdev_boot_setup_add - add new setup entry
534 * @name: name of the device
535 * @map: configured settings for the device
537 * Adds new setup entry to the dev_boot_setup list. The function
538 * returns 0 on error and 1 on success. This is a generic routine to
541 static int netdev_boot_setup_add(char *name, struct ifmap *map)
543 struct netdev_boot_setup *s;
547 for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++) {
548 if (s[i].name[0] == '\0' || s[i].name[0] == ' ') {
549 memset(s[i].name, 0, sizeof(s[i].name));
550 strlcpy(s[i].name, name, IFNAMSIZ);
551 memcpy(&s[i].map, map, sizeof(s[i].map));
556 return i >= NETDEV_BOOT_SETUP_MAX ? 0 : 1;
560 * netdev_boot_setup_check - check boot time settings
561 * @dev: the netdevice
563 * Check boot time settings for the device.
564 * The found settings are set for the device to be used
565 * later in the device probing.
566 * Returns 0 if no settings found, 1 if they are.
568 int netdev_boot_setup_check(struct net_device *dev)
570 struct netdev_boot_setup *s = dev_boot_setup;
573 for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++) {
574 if (s[i].name[0] != '\0' && s[i].name[0] != ' ' &&
575 !strcmp(dev->name, s[i].name)) {
576 dev->irq = s[i].map.irq;
577 dev->base_addr = s[i].map.base_addr;
578 dev->mem_start = s[i].map.mem_start;
579 dev->mem_end = s[i].map.mem_end;
585 EXPORT_SYMBOL(netdev_boot_setup_check);
589 * netdev_boot_base - get address from boot time settings
590 * @prefix: prefix for network device
591 * @unit: id for network device
593 * Check boot time settings for the base address of device.
594 * The found settings are set for the device to be used
595 * later in the device probing.
596 * Returns 0 if no settings found.
598 unsigned long netdev_boot_base(const char *prefix, int unit)
600 const struct netdev_boot_setup *s = dev_boot_setup;
604 sprintf(name, "%s%d", prefix, unit);
607 * If device already registered then return base of 1
608 * to indicate not to probe for this interface
610 if (__dev_get_by_name(&init_net, name))
613 for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++)
614 if (!strcmp(name, s[i].name))
615 return s[i].map.base_addr;
620 * Saves at boot time configured settings for any netdevice.
622 int __init netdev_boot_setup(char *str)
627 str = get_options(str, ARRAY_SIZE(ints), ints);
632 memset(&map, 0, sizeof(map));
636 map.base_addr = ints[2];
638 map.mem_start = ints[3];
640 map.mem_end = ints[4];
642 /* Add new entry to the list */
643 return netdev_boot_setup_add(str, &map);
646 __setup("netdev=", netdev_boot_setup);
648 /*******************************************************************************
650 Device Interface Subroutines
652 *******************************************************************************/
655 * __dev_get_by_name - find a device by its name
656 * @net: the applicable net namespace
657 * @name: name to find
659 * Find an interface by name. Must be called under RTNL semaphore
660 * or @dev_base_lock. If the name is found a pointer to the device
661 * is returned. If the name is not found then %NULL is returned. The
662 * reference counters are not incremented so the caller must be
663 * careful with locks.
666 struct net_device *__dev_get_by_name(struct net *net, const char *name)
668 struct net_device *dev;
669 struct hlist_head *head = dev_name_hash(net, name);
671 hlist_for_each_entry(dev, head, name_hlist)
672 if (!strncmp(dev->name, name, IFNAMSIZ))
677 EXPORT_SYMBOL(__dev_get_by_name);
680 * dev_get_by_name_rcu - find a device by its name
681 * @net: the applicable net namespace
682 * @name: name to find
684 * Find an interface by name.
685 * If the name is found a pointer to the device is returned.
686 * If the name is not found then %NULL is returned.
687 * The reference counters are not incremented so the caller must be
688 * careful with locks. The caller must hold RCU lock.
691 struct net_device *dev_get_by_name_rcu(struct net *net, const char *name)
693 struct net_device *dev;
694 struct hlist_head *head = dev_name_hash(net, name);
696 hlist_for_each_entry_rcu(dev, head, name_hlist)
697 if (!strncmp(dev->name, name, IFNAMSIZ))
702 EXPORT_SYMBOL(dev_get_by_name_rcu);
705 * dev_get_by_name - find a device by its name
706 * @net: the applicable net namespace
707 * @name: name to find
709 * Find an interface by name. This can be called from any
710 * context and does its own locking. The returned handle has
711 * the usage count incremented and the caller must use dev_put() to
712 * release it when it is no longer needed. %NULL is returned if no
713 * matching device is found.
716 struct net_device *dev_get_by_name(struct net *net, const char *name)
718 struct net_device *dev;
721 dev = dev_get_by_name_rcu(net, name);
727 EXPORT_SYMBOL(dev_get_by_name);
730 * __dev_get_by_index - find a device by its ifindex
731 * @net: the applicable net namespace
732 * @ifindex: index of device
734 * Search for an interface by index. Returns %NULL if the device
735 * is not found or a pointer to the device. The device has not
736 * had its reference counter increased so the caller must be careful
737 * about locking. The caller must hold either the RTNL semaphore
741 struct net_device *__dev_get_by_index(struct net *net, int ifindex)
743 struct net_device *dev;
744 struct hlist_head *head = dev_index_hash(net, ifindex);
746 hlist_for_each_entry(dev, head, index_hlist)
747 if (dev->ifindex == ifindex)
752 EXPORT_SYMBOL(__dev_get_by_index);
755 * dev_get_by_index_rcu - find a device by its ifindex
756 * @net: the applicable net namespace
757 * @ifindex: index of device
759 * Search for an interface by index. Returns %NULL if the device
760 * is not found or a pointer to the device. The device has not
761 * had its reference counter increased so the caller must be careful
762 * about locking. The caller must hold RCU lock.
765 struct net_device *dev_get_by_index_rcu(struct net *net, int ifindex)
767 struct net_device *dev;
768 struct hlist_head *head = dev_index_hash(net, ifindex);
770 hlist_for_each_entry_rcu(dev, head, index_hlist)
771 if (dev->ifindex == ifindex)
776 EXPORT_SYMBOL(dev_get_by_index_rcu);
780 * dev_get_by_index - find a device by its ifindex
781 * @net: the applicable net namespace
782 * @ifindex: index of device
784 * Search for an interface by index. Returns NULL if the device
785 * is not found or a pointer to the device. The device returned has
786 * had a reference added and the pointer is safe until the user calls
787 * dev_put to indicate they have finished with it.
790 struct net_device *dev_get_by_index(struct net *net, int ifindex)
792 struct net_device *dev;
795 dev = dev_get_by_index_rcu(net, ifindex);
801 EXPORT_SYMBOL(dev_get_by_index);
804 * netdev_get_name - get a netdevice name, knowing its ifindex.
805 * @net: network namespace
806 * @name: a pointer to the buffer where the name will be stored.
807 * @ifindex: the ifindex of the interface to get the name from.
809 * The use of raw_seqcount_begin() and cond_resched() before
810 * retrying is required as we want to give the writers a chance
811 * to complete when CONFIG_PREEMPT is not set.
813 int netdev_get_name(struct net *net, char *name, int ifindex)
815 struct net_device *dev;
819 seq = raw_seqcount_begin(&devnet_rename_seq);
821 dev = dev_get_by_index_rcu(net, ifindex);
827 strcpy(name, dev->name);
829 if (read_seqcount_retry(&devnet_rename_seq, seq)) {
838 * dev_getbyhwaddr_rcu - find a device by its hardware address
839 * @net: the applicable net namespace
840 * @type: media type of device
841 * @ha: hardware address
843 * Search for an interface by MAC address. Returns NULL if the device
844 * is not found or a pointer to the device.
845 * The caller must hold RCU or RTNL.
846 * The returned device has not had its ref count increased
847 * and the caller must therefore be careful about locking
851 struct net_device *dev_getbyhwaddr_rcu(struct net *net, unsigned short type,
854 struct net_device *dev;
856 for_each_netdev_rcu(net, dev)
857 if (dev->type == type &&
858 !memcmp(dev->dev_addr, ha, dev->addr_len))
863 EXPORT_SYMBOL(dev_getbyhwaddr_rcu);
865 struct net_device *__dev_getfirstbyhwtype(struct net *net, unsigned short type)
867 struct net_device *dev;
870 for_each_netdev(net, dev)
871 if (dev->type == type)
876 EXPORT_SYMBOL(__dev_getfirstbyhwtype);
878 struct net_device *dev_getfirstbyhwtype(struct net *net, unsigned short type)
880 struct net_device *dev, *ret = NULL;
883 for_each_netdev_rcu(net, dev)
884 if (dev->type == type) {
892 EXPORT_SYMBOL(dev_getfirstbyhwtype);
895 * dev_get_by_flags_rcu - find any device with given flags
896 * @net: the applicable net namespace
897 * @if_flags: IFF_* values
898 * @mask: bitmask of bits in if_flags to check
900 * Search for any interface with the given flags. Returns NULL if a device
901 * is not found or a pointer to the device. Must be called inside
902 * rcu_read_lock(), and result refcount is unchanged.
905 struct net_device *dev_get_by_flags_rcu(struct net *net, unsigned short if_flags,
908 struct net_device *dev, *ret;
911 for_each_netdev_rcu(net, dev) {
912 if (((dev->flags ^ if_flags) & mask) == 0) {
919 EXPORT_SYMBOL(dev_get_by_flags_rcu);
922 * dev_valid_name - check if name is okay for network device
925 * Network device names need to be valid file names to
926 * to allow sysfs to work. We also disallow any kind of
929 bool dev_valid_name(const char *name)
933 if (strlen(name) >= IFNAMSIZ)
935 if (!strcmp(name, ".") || !strcmp(name, ".."))
939 if (*name == '/' || isspace(*name))
945 EXPORT_SYMBOL(dev_valid_name);
948 * __dev_alloc_name - allocate a name for a device
949 * @net: network namespace to allocate the device name in
950 * @name: name format string
951 * @buf: scratch buffer and result name string
953 * Passed a format string - eg "lt%d" it will try and find a suitable
954 * id. It scans list of devices to build up a free map, then chooses
955 * the first empty slot. The caller must hold the dev_base or rtnl lock
956 * while allocating the name and adding the device in order to avoid
958 * Limited to bits_per_byte * page size devices (ie 32K on most platforms).
959 * Returns the number of the unit assigned or a negative errno code.
962 static int __dev_alloc_name(struct net *net, const char *name, char *buf)
966 const int max_netdevices = 8*PAGE_SIZE;
967 unsigned long *inuse;
968 struct net_device *d;
970 p = strnchr(name, IFNAMSIZ-1, '%');
973 * Verify the string as this thing may have come from
974 * the user. There must be either one "%d" and no other "%"
977 if (p[1] != 'd' || strchr(p + 2, '%'))
980 /* Use one page as a bit array of possible slots */
981 inuse = (unsigned long *) get_zeroed_page(GFP_ATOMIC);
985 for_each_netdev(net, d) {
986 if (!sscanf(d->name, name, &i))
988 if (i < 0 || i >= max_netdevices)
991 /* avoid cases where sscanf is not exact inverse of printf */
992 snprintf(buf, IFNAMSIZ, name, i);
993 if (!strncmp(buf, d->name, IFNAMSIZ))
997 i = find_first_zero_bit(inuse, max_netdevices);
998 free_page((unsigned long) inuse);
1002 snprintf(buf, IFNAMSIZ, name, i);
1003 if (!__dev_get_by_name(net, buf))
1006 /* It is possible to run out of possible slots
1007 * when the name is long and there isn't enough space left
1008 * for the digits, or if all bits are used.
1014 * dev_alloc_name - allocate a name for a device
1016 * @name: name format string
1018 * Passed a format string - eg "lt%d" it will try and find a suitable
1019 * id. It scans list of devices to build up a free map, then chooses
1020 * the first empty slot. The caller must hold the dev_base or rtnl lock
1021 * while allocating the name and adding the device in order to avoid
1023 * Limited to bits_per_byte * page size devices (ie 32K on most platforms).
1024 * Returns the number of the unit assigned or a negative errno code.
1027 int dev_alloc_name(struct net_device *dev, const char *name)
1033 BUG_ON(!dev_net(dev));
1035 ret = __dev_alloc_name(net, name, buf);
1037 strlcpy(dev->name, buf, IFNAMSIZ);
1040 EXPORT_SYMBOL(dev_alloc_name);
1042 static int dev_alloc_name_ns(struct net *net,
1043 struct net_device *dev,
1049 ret = __dev_alloc_name(net, name, buf);
1051 strlcpy(dev->name, buf, IFNAMSIZ);
1055 static int dev_get_valid_name(struct net *net,
1056 struct net_device *dev,
1061 if (!dev_valid_name(name))
1064 if (strchr(name, '%'))
1065 return dev_alloc_name_ns(net, dev, name);
1066 else if (__dev_get_by_name(net, name))
1068 else if (dev->name != name)
1069 strlcpy(dev->name, name, IFNAMSIZ);
1075 * dev_change_name - change name of a device
1077 * @newname: name (or format string) must be at least IFNAMSIZ
1079 * Change name of a device, can pass format strings "eth%d".
1082 int dev_change_name(struct net_device *dev, const char *newname)
1084 char oldname[IFNAMSIZ];
1090 BUG_ON(!dev_net(dev));
1093 if (dev->flags & IFF_UP)
1096 write_seqcount_begin(&devnet_rename_seq);
1098 if (strncmp(newname, dev->name, IFNAMSIZ) == 0) {
1099 write_seqcount_end(&devnet_rename_seq);
1103 memcpy(oldname, dev->name, IFNAMSIZ);
1105 err = dev_get_valid_name(net, dev, newname);
1107 write_seqcount_end(&devnet_rename_seq);
1112 ret = device_rename(&dev->dev, dev->name);
1114 memcpy(dev->name, oldname, IFNAMSIZ);
1115 write_seqcount_end(&devnet_rename_seq);
1119 write_seqcount_end(&devnet_rename_seq);
1121 write_lock_bh(&dev_base_lock);
1122 hlist_del_rcu(&dev->name_hlist);
1123 write_unlock_bh(&dev_base_lock);
1127 write_lock_bh(&dev_base_lock);
1128 hlist_add_head_rcu(&dev->name_hlist, dev_name_hash(net, dev->name));
1129 write_unlock_bh(&dev_base_lock);
1131 ret = call_netdevice_notifiers(NETDEV_CHANGENAME, dev);
1132 ret = notifier_to_errno(ret);
1135 /* err >= 0 after dev_alloc_name() or stores the first errno */
1138 write_seqcount_begin(&devnet_rename_seq);
1139 memcpy(dev->name, oldname, IFNAMSIZ);
1142 pr_err("%s: name change rollback failed: %d\n",
1151 * dev_set_alias - change ifalias of a device
1153 * @alias: name up to IFALIASZ
1154 * @len: limit of bytes to copy from info
1156 * Set ifalias for a device,
1158 int dev_set_alias(struct net_device *dev, const char *alias, size_t len)
1164 if (len >= IFALIASZ)
1168 kfree(dev->ifalias);
1169 dev->ifalias = NULL;
1173 new_ifalias = krealloc(dev->ifalias, len + 1, GFP_KERNEL);
1176 dev->ifalias = new_ifalias;
1178 strlcpy(dev->ifalias, alias, len+1);
1184 * netdev_features_change - device changes features
1185 * @dev: device to cause notification
1187 * Called to indicate a device has changed features.
1189 void netdev_features_change(struct net_device *dev)
1191 call_netdevice_notifiers(NETDEV_FEAT_CHANGE, dev);
1193 EXPORT_SYMBOL(netdev_features_change);
1196 * netdev_state_change - device changes state
1197 * @dev: device to cause notification
1199 * Called to indicate a device has changed state. This function calls
1200 * the notifier chains for netdev_chain and sends a NEWLINK message
1201 * to the routing socket.
1203 void netdev_state_change(struct net_device *dev)
1205 if (dev->flags & IFF_UP) {
1206 call_netdevice_notifiers(NETDEV_CHANGE, dev);
1207 rtmsg_ifinfo(RTM_NEWLINK, dev, 0, GFP_KERNEL);
1210 EXPORT_SYMBOL(netdev_state_change);
1213 * netdev_notify_peers - notify network peers about existence of @dev
1214 * @dev: network device
1216 * Generate traffic such that interested network peers are aware of
1217 * @dev, such as by generating a gratuitous ARP. This may be used when
1218 * a device wants to inform the rest of the network about some sort of
1219 * reconfiguration such as a failover event or virtual machine
1222 void netdev_notify_peers(struct net_device *dev)
1225 call_netdevice_notifiers(NETDEV_NOTIFY_PEERS, dev);
1228 EXPORT_SYMBOL(netdev_notify_peers);
1230 static int __dev_open(struct net_device *dev)
1232 const struct net_device_ops *ops = dev->netdev_ops;
1237 if (!netif_device_present(dev))
1240 /* Block netpoll from trying to do any rx path servicing.
1241 * If we don't do this there is a chance ndo_poll_controller
1242 * or ndo_poll may be running while we open the device
1244 netpoll_rx_disable(dev);
1246 ret = call_netdevice_notifiers(NETDEV_PRE_UP, dev);
1247 ret = notifier_to_errno(ret);
1251 set_bit(__LINK_STATE_START, &dev->state);
1253 if (ops->ndo_validate_addr)
1254 ret = ops->ndo_validate_addr(dev);
1256 if (!ret && ops->ndo_open)
1257 ret = ops->ndo_open(dev);
1259 netpoll_rx_enable(dev);
1262 clear_bit(__LINK_STATE_START, &dev->state);
1264 dev->flags |= IFF_UP;
1265 net_dmaengine_get();
1266 dev_set_rx_mode(dev);
1268 add_device_randomness(dev->dev_addr, dev->addr_len);
1275 * dev_open - prepare an interface for use.
1276 * @dev: device to open
1278 * Takes a device from down to up state. The device's private open
1279 * function is invoked and then the multicast lists are loaded. Finally
1280 * the device is moved into the up state and a %NETDEV_UP message is
1281 * sent to the netdev notifier chain.
1283 * Calling this function on an active interface is a nop. On a failure
1284 * a negative errno code is returned.
1286 int dev_open(struct net_device *dev)
1290 if (dev->flags & IFF_UP)
1293 ret = __dev_open(dev);
1297 rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP|IFF_RUNNING, GFP_KERNEL);
1298 call_netdevice_notifiers(NETDEV_UP, dev);
1302 EXPORT_SYMBOL(dev_open);
1304 static int __dev_close_many(struct list_head *head)
1306 struct net_device *dev;
1311 list_for_each_entry(dev, head, close_list) {
1312 call_netdevice_notifiers(NETDEV_GOING_DOWN, dev);
1314 clear_bit(__LINK_STATE_START, &dev->state);
1316 /* Synchronize to scheduled poll. We cannot touch poll list, it
1317 * can be even on different cpu. So just clear netif_running().
1319 * dev->stop() will invoke napi_disable() on all of it's
1320 * napi_struct instances on this device.
1322 smp_mb__after_clear_bit(); /* Commit netif_running(). */
1325 dev_deactivate_many(head);
1327 list_for_each_entry(dev, head, close_list) {
1328 const struct net_device_ops *ops = dev->netdev_ops;
1331 * Call the device specific close. This cannot fail.
1332 * Only if device is UP
1334 * We allow it to be called even after a DETACH hot-plug
1340 dev->flags &= ~IFF_UP;
1341 net_dmaengine_put();
1347 static int __dev_close(struct net_device *dev)
1352 /* Temporarily disable netpoll until the interface is down */
1353 netpoll_rx_disable(dev);
1355 list_add(&dev->close_list, &single);
1356 retval = __dev_close_many(&single);
1359 netpoll_rx_enable(dev);
1363 static int dev_close_many(struct list_head *head)
1365 struct net_device *dev, *tmp;
1367 /* Remove the devices that don't need to be closed */
1368 list_for_each_entry_safe(dev, tmp, head, close_list)
1369 if (!(dev->flags & IFF_UP))
1370 list_del_init(&dev->close_list);
1372 __dev_close_many(head);
1374 list_for_each_entry_safe(dev, tmp, head, close_list) {
1375 rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP|IFF_RUNNING, GFP_KERNEL);
1376 call_netdevice_notifiers(NETDEV_DOWN, dev);
1377 list_del_init(&dev->close_list);
1384 * dev_close - shutdown an interface.
1385 * @dev: device to shutdown
1387 * This function moves an active device into down state. A
1388 * %NETDEV_GOING_DOWN is sent to the netdev notifier chain. The device
1389 * is then deactivated and finally a %NETDEV_DOWN is sent to the notifier
1392 int dev_close(struct net_device *dev)
1394 if (dev->flags & IFF_UP) {
1397 /* Block netpoll rx while the interface is going down */
1398 netpoll_rx_disable(dev);
1400 list_add(&dev->close_list, &single);
1401 dev_close_many(&single);
1404 netpoll_rx_enable(dev);
1408 EXPORT_SYMBOL(dev_close);
1412 * dev_disable_lro - disable Large Receive Offload on a device
1415 * Disable Large Receive Offload (LRO) on a net device. Must be
1416 * called under RTNL. This is needed if received packets may be
1417 * forwarded to another interface.
1419 void dev_disable_lro(struct net_device *dev)
1422 * If we're trying to disable lro on a vlan device
1423 * use the underlying physical device instead
1425 if (is_vlan_dev(dev))
1426 dev = vlan_dev_real_dev(dev);
1428 /* the same for macvlan devices */
1429 if (netif_is_macvlan(dev))
1430 dev = macvlan_dev_real_dev(dev);
1432 dev->wanted_features &= ~NETIF_F_LRO;
1433 netdev_update_features(dev);
1435 if (unlikely(dev->features & NETIF_F_LRO))
1436 netdev_WARN(dev, "failed to disable LRO!\n");
1438 EXPORT_SYMBOL(dev_disable_lro);
1440 static int call_netdevice_notifier(struct notifier_block *nb, unsigned long val,
1441 struct net_device *dev)
1443 struct netdev_notifier_info info;
1445 netdev_notifier_info_init(&info, dev);
1446 return nb->notifier_call(nb, val, &info);
1449 static int dev_boot_phase = 1;
1452 * register_netdevice_notifier - register a network notifier block
1455 * Register a notifier to be called when network device events occur.
1456 * The notifier passed is linked into the kernel structures and must
1457 * not be reused until it has been unregistered. A negative errno code
1458 * is returned on a failure.
1460 * When registered all registration and up events are replayed
1461 * to the new notifier to allow device to have a race free
1462 * view of the network device list.
1465 int register_netdevice_notifier(struct notifier_block *nb)
1467 struct net_device *dev;
1468 struct net_device *last;
1473 err = raw_notifier_chain_register(&netdev_chain, nb);
1479 for_each_netdev(net, dev) {
1480 err = call_netdevice_notifier(nb, NETDEV_REGISTER, dev);
1481 err = notifier_to_errno(err);
1485 if (!(dev->flags & IFF_UP))
1488 call_netdevice_notifier(nb, NETDEV_UP, dev);
1499 for_each_netdev(net, dev) {
1503 if (dev->flags & IFF_UP) {
1504 call_netdevice_notifier(nb, NETDEV_GOING_DOWN,
1506 call_netdevice_notifier(nb, NETDEV_DOWN, dev);
1508 call_netdevice_notifier(nb, NETDEV_UNREGISTER, dev);
1513 raw_notifier_chain_unregister(&netdev_chain, nb);
1516 EXPORT_SYMBOL(register_netdevice_notifier);
1519 * unregister_netdevice_notifier - unregister a network notifier block
1522 * Unregister a notifier previously registered by
1523 * register_netdevice_notifier(). The notifier is unlinked into the
1524 * kernel structures and may then be reused. A negative errno code
1525 * is returned on a failure.
1527 * After unregistering unregister and down device events are synthesized
1528 * for all devices on the device list to the removed notifier to remove
1529 * the need for special case cleanup code.
1532 int unregister_netdevice_notifier(struct notifier_block *nb)
1534 struct net_device *dev;
1539 err = raw_notifier_chain_unregister(&netdev_chain, nb);
1544 for_each_netdev(net, dev) {
1545 if (dev->flags & IFF_UP) {
1546 call_netdevice_notifier(nb, NETDEV_GOING_DOWN,
1548 call_netdevice_notifier(nb, NETDEV_DOWN, dev);
1550 call_netdevice_notifier(nb, NETDEV_UNREGISTER, dev);
1557 EXPORT_SYMBOL(unregister_netdevice_notifier);
1560 * call_netdevice_notifiers_info - call all network notifier blocks
1561 * @val: value passed unmodified to notifier function
1562 * @dev: net_device pointer passed unmodified to notifier function
1563 * @info: notifier information data
1565 * Call all network notifier blocks. Parameters and return value
1566 * are as for raw_notifier_call_chain().
1569 int call_netdevice_notifiers_info(unsigned long val, struct net_device *dev,
1570 struct netdev_notifier_info *info)
1573 netdev_notifier_info_init(info, dev);
1574 return raw_notifier_call_chain(&netdev_chain, val, info);
1576 EXPORT_SYMBOL(call_netdevice_notifiers_info);
1579 * call_netdevice_notifiers - call all network notifier blocks
1580 * @val: value passed unmodified to notifier function
1581 * @dev: net_device pointer passed unmodified to notifier function
1583 * Call all network notifier blocks. Parameters and return value
1584 * are as for raw_notifier_call_chain().
1587 int call_netdevice_notifiers(unsigned long val, struct net_device *dev)
1589 struct netdev_notifier_info info;
1591 return call_netdevice_notifiers_info(val, dev, &info);
1593 EXPORT_SYMBOL(call_netdevice_notifiers);
1595 static struct static_key netstamp_needed __read_mostly;
1596 #ifdef HAVE_JUMP_LABEL
1597 /* We are not allowed to call static_key_slow_dec() from irq context
1598 * If net_disable_timestamp() is called from irq context, defer the
1599 * static_key_slow_dec() calls.
1601 static atomic_t netstamp_needed_deferred;
1604 void net_enable_timestamp(void)
1606 #ifdef HAVE_JUMP_LABEL
1607 int deferred = atomic_xchg(&netstamp_needed_deferred, 0);
1611 static_key_slow_dec(&netstamp_needed);
1615 static_key_slow_inc(&netstamp_needed);
1617 EXPORT_SYMBOL(net_enable_timestamp);
1619 void net_disable_timestamp(void)
1621 #ifdef HAVE_JUMP_LABEL
1622 if (in_interrupt()) {
1623 atomic_inc(&netstamp_needed_deferred);
1627 static_key_slow_dec(&netstamp_needed);
1629 EXPORT_SYMBOL(net_disable_timestamp);
1631 static inline void net_timestamp_set(struct sk_buff *skb)
1633 skb->tstamp.tv64 = 0;
1634 if (static_key_false(&netstamp_needed))
1635 __net_timestamp(skb);
1638 #define net_timestamp_check(COND, SKB) \
1639 if (static_key_false(&netstamp_needed)) { \
1640 if ((COND) && !(SKB)->tstamp.tv64) \
1641 __net_timestamp(SKB); \
1644 static inline bool is_skb_forwardable(struct net_device *dev,
1645 struct sk_buff *skb)
1649 if (!(dev->flags & IFF_UP))
1652 len = dev->mtu + dev->hard_header_len + VLAN_HLEN;
1653 if (skb->len <= len)
1656 /* if TSO is enabled, we don't care about the length as the packet
1657 * could be forwarded without being segmented before
1659 if (skb_is_gso(skb))
1666 * dev_forward_skb - loopback an skb to another netif
1668 * @dev: destination network device
1669 * @skb: buffer to forward
1672 * NET_RX_SUCCESS (no congestion)
1673 * NET_RX_DROP (packet was dropped, but freed)
1675 * dev_forward_skb can be used for injecting an skb from the
1676 * start_xmit function of one device into the receive queue
1677 * of another device.
1679 * The receiving device may be in another namespace, so
1680 * we have to clear all information in the skb that could
1681 * impact namespace isolation.
1683 int dev_forward_skb(struct net_device *dev, struct sk_buff *skb)
1685 if (skb_shinfo(skb)->tx_flags & SKBTX_DEV_ZEROCOPY) {
1686 if (skb_copy_ubufs(skb, GFP_ATOMIC)) {
1687 atomic_long_inc(&dev->rx_dropped);
1693 if (unlikely(!is_skb_forwardable(dev, skb))) {
1694 atomic_long_inc(&dev->rx_dropped);
1699 skb_scrub_packet(skb, true);
1700 skb->protocol = eth_type_trans(skb, dev);
1702 return netif_rx(skb);
1704 EXPORT_SYMBOL_GPL(dev_forward_skb);
1706 static inline int deliver_skb(struct sk_buff *skb,
1707 struct packet_type *pt_prev,
1708 struct net_device *orig_dev)
1710 if (unlikely(skb_orphan_frags(skb, GFP_ATOMIC)))
1712 atomic_inc(&skb->users);
1713 return pt_prev->func(skb, skb->dev, pt_prev, orig_dev);
1716 static inline bool skb_loop_sk(struct packet_type *ptype, struct sk_buff *skb)
1718 if (!ptype->af_packet_priv || !skb->sk)
1721 if (ptype->id_match)
1722 return ptype->id_match(ptype, skb->sk);
1723 else if ((struct sock *)ptype->af_packet_priv == skb->sk)
1730 * Support routine. Sends outgoing frames to any network
1731 * taps currently in use.
1734 static void dev_queue_xmit_nit(struct sk_buff *skb, struct net_device *dev)
1736 struct packet_type *ptype;
1737 struct sk_buff *skb2 = NULL;
1738 struct packet_type *pt_prev = NULL;
1741 list_for_each_entry_rcu(ptype, &ptype_all, list) {
1742 /* Never send packets back to the socket
1743 * they originated from - MvS (miquels@drinkel.ow.org)
1745 if ((ptype->dev == dev || !ptype->dev) &&
1746 (!skb_loop_sk(ptype, skb))) {
1748 deliver_skb(skb2, pt_prev, skb->dev);
1753 skb2 = skb_clone(skb, GFP_ATOMIC);
1757 net_timestamp_set(skb2);
1759 /* skb->nh should be correctly
1760 set by sender, so that the second statement is
1761 just protection against buggy protocols.
1763 skb_reset_mac_header(skb2);
1765 if (skb_network_header(skb2) < skb2->data ||
1766 skb_network_header(skb2) > skb_tail_pointer(skb2)) {
1767 net_crit_ratelimited("protocol %04x is buggy, dev %s\n",
1768 ntohs(skb2->protocol),
1770 skb_reset_network_header(skb2);
1773 skb2->transport_header = skb2->network_header;
1774 skb2->pkt_type = PACKET_OUTGOING;
1779 pt_prev->func(skb2, skb->dev, pt_prev, skb->dev);
1784 * netif_setup_tc - Handle tc mappings on real_num_tx_queues change
1785 * @dev: Network device
1786 * @txq: number of queues available
1788 * If real_num_tx_queues is changed the tc mappings may no longer be
1789 * valid. To resolve this verify the tc mapping remains valid and if
1790 * not NULL the mapping. With no priorities mapping to this
1791 * offset/count pair it will no longer be used. In the worst case TC0
1792 * is invalid nothing can be done so disable priority mappings. If is
1793 * expected that drivers will fix this mapping if they can before
1794 * calling netif_set_real_num_tx_queues.
1796 static void netif_setup_tc(struct net_device *dev, unsigned int txq)
1799 struct netdev_tc_txq *tc = &dev->tc_to_txq[0];
1801 /* If TC0 is invalidated disable TC mapping */
1802 if (tc->offset + tc->count > txq) {
1803 pr_warn("Number of in use tx queues changed invalidating tc mappings. Priority traffic classification disabled!\n");
1808 /* Invalidated prio to tc mappings set to TC0 */
1809 for (i = 1; i < TC_BITMASK + 1; i++) {
1810 int q = netdev_get_prio_tc_map(dev, i);
1812 tc = &dev->tc_to_txq[q];
1813 if (tc->offset + tc->count > txq) {
1814 pr_warn("Number of in use tx queues changed. Priority %i to tc mapping %i is no longer valid. Setting map to 0\n",
1816 netdev_set_prio_tc_map(dev, i, 0);
1822 static DEFINE_MUTEX(xps_map_mutex);
1823 #define xmap_dereference(P) \
1824 rcu_dereference_protected((P), lockdep_is_held(&xps_map_mutex))
1826 static struct xps_map *remove_xps_queue(struct xps_dev_maps *dev_maps,
1829 struct xps_map *map = NULL;
1833 map = xmap_dereference(dev_maps->cpu_map[cpu]);
1835 for (pos = 0; map && pos < map->len; pos++) {
1836 if (map->queues[pos] == index) {
1838 map->queues[pos] = map->queues[--map->len];
1840 RCU_INIT_POINTER(dev_maps->cpu_map[cpu], NULL);
1841 kfree_rcu(map, rcu);
1851 static void netif_reset_xps_queues_gt(struct net_device *dev, u16 index)
1853 struct xps_dev_maps *dev_maps;
1855 bool active = false;
1857 mutex_lock(&xps_map_mutex);
1858 dev_maps = xmap_dereference(dev->xps_maps);
1863 for_each_possible_cpu(cpu) {
1864 for (i = index; i < dev->num_tx_queues; i++) {
1865 if (!remove_xps_queue(dev_maps, cpu, i))
1868 if (i == dev->num_tx_queues)
1873 RCU_INIT_POINTER(dev->xps_maps, NULL);
1874 kfree_rcu(dev_maps, rcu);
1877 for (i = index; i < dev->num_tx_queues; i++)
1878 netdev_queue_numa_node_write(netdev_get_tx_queue(dev, i),
1882 mutex_unlock(&xps_map_mutex);
1885 static struct xps_map *expand_xps_map(struct xps_map *map,
1888 struct xps_map *new_map;
1889 int alloc_len = XPS_MIN_MAP_ALLOC;
1892 for (pos = 0; map && pos < map->len; pos++) {
1893 if (map->queues[pos] != index)
1898 /* Need to add queue to this CPU's existing map */
1900 if (pos < map->alloc_len)
1903 alloc_len = map->alloc_len * 2;
1906 /* Need to allocate new map to store queue on this CPU's map */
1907 new_map = kzalloc_node(XPS_MAP_SIZE(alloc_len), GFP_KERNEL,
1912 for (i = 0; i < pos; i++)
1913 new_map->queues[i] = map->queues[i];
1914 new_map->alloc_len = alloc_len;
1920 int netif_set_xps_queue(struct net_device *dev, const struct cpumask *mask,
1923 struct xps_dev_maps *dev_maps, *new_dev_maps = NULL;
1924 struct xps_map *map, *new_map;
1925 int maps_sz = max_t(unsigned int, XPS_DEV_MAPS_SIZE, L1_CACHE_BYTES);
1926 int cpu, numa_node_id = -2;
1927 bool active = false;
1929 mutex_lock(&xps_map_mutex);
1931 dev_maps = xmap_dereference(dev->xps_maps);
1933 /* allocate memory for queue storage */
1934 for_each_online_cpu(cpu) {
1935 if (!cpumask_test_cpu(cpu, mask))
1939 new_dev_maps = kzalloc(maps_sz, GFP_KERNEL);
1940 if (!new_dev_maps) {
1941 mutex_unlock(&xps_map_mutex);
1945 map = dev_maps ? xmap_dereference(dev_maps->cpu_map[cpu]) :
1948 map = expand_xps_map(map, cpu, index);
1952 RCU_INIT_POINTER(new_dev_maps->cpu_map[cpu], map);
1956 goto out_no_new_maps;
1958 for_each_possible_cpu(cpu) {
1959 if (cpumask_test_cpu(cpu, mask) && cpu_online(cpu)) {
1960 /* add queue to CPU maps */
1963 map = xmap_dereference(new_dev_maps->cpu_map[cpu]);
1964 while ((pos < map->len) && (map->queues[pos] != index))
1967 if (pos == map->len)
1968 map->queues[map->len++] = index;
1970 if (numa_node_id == -2)
1971 numa_node_id = cpu_to_node(cpu);
1972 else if (numa_node_id != cpu_to_node(cpu))
1975 } else if (dev_maps) {
1976 /* fill in the new device map from the old device map */
1977 map = xmap_dereference(dev_maps->cpu_map[cpu]);
1978 RCU_INIT_POINTER(new_dev_maps->cpu_map[cpu], map);
1983 rcu_assign_pointer(dev->xps_maps, new_dev_maps);
1985 /* Cleanup old maps */
1987 for_each_possible_cpu(cpu) {
1988 new_map = xmap_dereference(new_dev_maps->cpu_map[cpu]);
1989 map = xmap_dereference(dev_maps->cpu_map[cpu]);
1990 if (map && map != new_map)
1991 kfree_rcu(map, rcu);
1994 kfree_rcu(dev_maps, rcu);
1997 dev_maps = new_dev_maps;
2001 /* update Tx queue numa node */
2002 netdev_queue_numa_node_write(netdev_get_tx_queue(dev, index),
2003 (numa_node_id >= 0) ? numa_node_id :
2009 /* removes queue from unused CPUs */
2010 for_each_possible_cpu(cpu) {
2011 if (cpumask_test_cpu(cpu, mask) && cpu_online(cpu))
2014 if (remove_xps_queue(dev_maps, cpu, index))
2018 /* free map if not active */
2020 RCU_INIT_POINTER(dev->xps_maps, NULL);
2021 kfree_rcu(dev_maps, rcu);
2025 mutex_unlock(&xps_map_mutex);
2029 /* remove any maps that we added */
2030 for_each_possible_cpu(cpu) {
2031 new_map = xmap_dereference(new_dev_maps->cpu_map[cpu]);
2032 map = dev_maps ? xmap_dereference(dev_maps->cpu_map[cpu]) :
2034 if (new_map && new_map != map)
2038 mutex_unlock(&xps_map_mutex);
2040 kfree(new_dev_maps);
2043 EXPORT_SYMBOL(netif_set_xps_queue);
2047 * Routine to help set real_num_tx_queues. To avoid skbs mapped to queues
2048 * greater then real_num_tx_queues stale skbs on the qdisc must be flushed.
2050 int netif_set_real_num_tx_queues(struct net_device *dev, unsigned int txq)
2054 if (txq < 1 || txq > dev->num_tx_queues)
2057 if (dev->reg_state == NETREG_REGISTERED ||
2058 dev->reg_state == NETREG_UNREGISTERING) {
2061 rc = netdev_queue_update_kobjects(dev, dev->real_num_tx_queues,
2067 netif_setup_tc(dev, txq);
2069 if (txq < dev->real_num_tx_queues) {
2070 qdisc_reset_all_tx_gt(dev, txq);
2072 netif_reset_xps_queues_gt(dev, txq);
2077 dev->real_num_tx_queues = txq;
2080 EXPORT_SYMBOL(netif_set_real_num_tx_queues);
2084 * netif_set_real_num_rx_queues - set actual number of RX queues used
2085 * @dev: Network device
2086 * @rxq: Actual number of RX queues
2088 * This must be called either with the rtnl_lock held or before
2089 * registration of the net device. Returns 0 on success, or a
2090 * negative error code. If called before registration, it always
2093 int netif_set_real_num_rx_queues(struct net_device *dev, unsigned int rxq)
2097 if (rxq < 1 || rxq > dev->num_rx_queues)
2100 if (dev->reg_state == NETREG_REGISTERED) {
2103 rc = net_rx_queue_update_kobjects(dev, dev->real_num_rx_queues,
2109 dev->real_num_rx_queues = rxq;
2112 EXPORT_SYMBOL(netif_set_real_num_rx_queues);
2116 * netif_get_num_default_rss_queues - default number of RSS queues
2118 * This routine should set an upper limit on the number of RSS queues
2119 * used by default by multiqueue devices.
2121 int netif_get_num_default_rss_queues(void)
2123 return min_t(int, DEFAULT_MAX_NUM_RSS_QUEUES, num_online_cpus());
2125 EXPORT_SYMBOL(netif_get_num_default_rss_queues);
2127 static inline void __netif_reschedule(struct Qdisc *q)
2129 struct softnet_data *sd;
2130 unsigned long flags;
2132 local_irq_save(flags);
2133 sd = &__get_cpu_var(softnet_data);
2134 q->next_sched = NULL;
2135 *sd->output_queue_tailp = q;
2136 sd->output_queue_tailp = &q->next_sched;
2137 raise_softirq_irqoff(NET_TX_SOFTIRQ);
2138 local_irq_restore(flags);
2141 void __netif_schedule(struct Qdisc *q)
2143 if (!test_and_set_bit(__QDISC_STATE_SCHED, &q->state))
2144 __netif_reschedule(q);
2146 EXPORT_SYMBOL(__netif_schedule);
2148 struct dev_kfree_skb_cb {
2149 enum skb_free_reason reason;
2152 static struct dev_kfree_skb_cb *get_kfree_skb_cb(const struct sk_buff *skb)
2154 return (struct dev_kfree_skb_cb *)skb->cb;
2157 void __dev_kfree_skb_irq(struct sk_buff *skb, enum skb_free_reason reason)
2159 unsigned long flags;
2161 if (likely(atomic_read(&skb->users) == 1)) {
2163 atomic_set(&skb->users, 0);
2164 } else if (likely(!atomic_dec_and_test(&skb->users))) {
2167 get_kfree_skb_cb(skb)->reason = reason;
2168 local_irq_save(flags);
2169 skb->next = __this_cpu_read(softnet_data.completion_queue);
2170 __this_cpu_write(softnet_data.completion_queue, skb);
2171 raise_softirq_irqoff(NET_TX_SOFTIRQ);
2172 local_irq_restore(flags);
2174 EXPORT_SYMBOL(__dev_kfree_skb_irq);
2176 void __dev_kfree_skb_any(struct sk_buff *skb, enum skb_free_reason reason)
2178 if (in_irq() || irqs_disabled())
2179 __dev_kfree_skb_irq(skb, reason);
2183 EXPORT_SYMBOL(__dev_kfree_skb_any);
2187 * netif_device_detach - mark device as removed
2188 * @dev: network device
2190 * Mark device as removed from system and therefore no longer available.
2192 void netif_device_detach(struct net_device *dev)
2194 if (test_and_clear_bit(__LINK_STATE_PRESENT, &dev->state) &&
2195 netif_running(dev)) {
2196 netif_tx_stop_all_queues(dev);
2199 EXPORT_SYMBOL(netif_device_detach);
2202 * netif_device_attach - mark device as attached
2203 * @dev: network device
2205 * Mark device as attached from system and restart if needed.
2207 void netif_device_attach(struct net_device *dev)
2209 if (!test_and_set_bit(__LINK_STATE_PRESENT, &dev->state) &&
2210 netif_running(dev)) {
2211 netif_tx_wake_all_queues(dev);
2212 __netdev_watchdog_up(dev);
2215 EXPORT_SYMBOL(netif_device_attach);
2217 static void skb_warn_bad_offload(const struct sk_buff *skb)
2219 static const netdev_features_t null_features = 0;
2220 struct net_device *dev = skb->dev;
2221 const char *driver = "";
2223 if (!net_ratelimit())
2226 if (dev && dev->dev.parent)
2227 driver = dev_driver_string(dev->dev.parent);
2229 WARN(1, "%s: caps=(%pNF, %pNF) len=%d data_len=%d gso_size=%d "
2230 "gso_type=%d ip_summed=%d\n",
2231 driver, dev ? &dev->features : &null_features,
2232 skb->sk ? &skb->sk->sk_route_caps : &null_features,
2233 skb->len, skb->data_len, skb_shinfo(skb)->gso_size,
2234 skb_shinfo(skb)->gso_type, skb->ip_summed);
2238 * Invalidate hardware checksum when packet is to be mangled, and
2239 * complete checksum manually on outgoing path.
2241 int skb_checksum_help(struct sk_buff *skb)
2244 int ret = 0, offset;
2246 if (skb->ip_summed == CHECKSUM_COMPLETE)
2247 goto out_set_summed;
2249 if (unlikely(skb_shinfo(skb)->gso_size)) {
2250 skb_warn_bad_offload(skb);
2254 /* Before computing a checksum, we should make sure no frag could
2255 * be modified by an external entity : checksum could be wrong.
2257 if (skb_has_shared_frag(skb)) {
2258 ret = __skb_linearize(skb);
2263 offset = skb_checksum_start_offset(skb);
2264 BUG_ON(offset >= skb_headlen(skb));
2265 csum = skb_checksum(skb, offset, skb->len - offset, 0);
2267 offset += skb->csum_offset;
2268 BUG_ON(offset + sizeof(__sum16) > skb_headlen(skb));
2270 if (skb_cloned(skb) &&
2271 !skb_clone_writable(skb, offset + sizeof(__sum16))) {
2272 ret = pskb_expand_head(skb, 0, 0, GFP_ATOMIC);
2277 *(__sum16 *)(skb->data + offset) = csum_fold(csum);
2279 skb->ip_summed = CHECKSUM_NONE;
2283 EXPORT_SYMBOL(skb_checksum_help);
2285 __be16 skb_network_protocol(struct sk_buff *skb)
2287 __be16 type = skb->protocol;
2288 int vlan_depth = ETH_HLEN;
2290 /* Tunnel gso handlers can set protocol to ethernet. */
2291 if (type == htons(ETH_P_TEB)) {
2294 if (unlikely(!pskb_may_pull(skb, sizeof(struct ethhdr))))
2297 eth = (struct ethhdr *)skb_mac_header(skb);
2298 type = eth->h_proto;
2301 while (type == htons(ETH_P_8021Q) || type == htons(ETH_P_8021AD)) {
2302 struct vlan_hdr *vh;
2304 if (unlikely(!pskb_may_pull(skb, vlan_depth + VLAN_HLEN)))
2307 vh = (struct vlan_hdr *)(skb->data + vlan_depth);
2308 type = vh->h_vlan_encapsulated_proto;
2309 vlan_depth += VLAN_HLEN;
2316 * skb_mac_gso_segment - mac layer segmentation handler.
2317 * @skb: buffer to segment
2318 * @features: features for the output path (see dev->features)
2320 struct sk_buff *skb_mac_gso_segment(struct sk_buff *skb,
2321 netdev_features_t features)
2323 struct sk_buff *segs = ERR_PTR(-EPROTONOSUPPORT);
2324 struct packet_offload *ptype;
2325 __be16 type = skb_network_protocol(skb);
2327 if (unlikely(!type))
2328 return ERR_PTR(-EINVAL);
2330 __skb_pull(skb, skb->mac_len);
2333 list_for_each_entry_rcu(ptype, &offload_base, list) {
2334 if (ptype->type == type && ptype->callbacks.gso_segment) {
2335 if (unlikely(skb->ip_summed != CHECKSUM_PARTIAL)) {
2338 err = ptype->callbacks.gso_send_check(skb);
2339 segs = ERR_PTR(err);
2340 if (err || skb_gso_ok(skb, features))
2342 __skb_push(skb, (skb->data -
2343 skb_network_header(skb)));
2345 segs = ptype->callbacks.gso_segment(skb, features);
2351 __skb_push(skb, skb->data - skb_mac_header(skb));
2355 EXPORT_SYMBOL(skb_mac_gso_segment);
2358 /* openvswitch calls this on rx path, so we need a different check.
2360 static inline bool skb_needs_check(struct sk_buff *skb, bool tx_path)
2363 return skb->ip_summed != CHECKSUM_PARTIAL;
2365 return skb->ip_summed == CHECKSUM_NONE;
2369 * __skb_gso_segment - Perform segmentation on skb.
2370 * @skb: buffer to segment
2371 * @features: features for the output path (see dev->features)
2372 * @tx_path: whether it is called in TX path
2374 * This function segments the given skb and returns a list of segments.
2376 * It may return NULL if the skb requires no segmentation. This is
2377 * only possible when GSO is used for verifying header integrity.
2379 struct sk_buff *__skb_gso_segment(struct sk_buff *skb,
2380 netdev_features_t features, bool tx_path)
2382 if (unlikely(skb_needs_check(skb, tx_path))) {
2385 skb_warn_bad_offload(skb);
2387 if (skb_header_cloned(skb) &&
2388 (err = pskb_expand_head(skb, 0, 0, GFP_ATOMIC)))
2389 return ERR_PTR(err);
2392 SKB_GSO_CB(skb)->mac_offset = skb_headroom(skb);
2393 SKB_GSO_CB(skb)->encap_level = 0;
2395 skb_reset_mac_header(skb);
2396 skb_reset_mac_len(skb);
2398 return skb_mac_gso_segment(skb, features);
2400 EXPORT_SYMBOL(__skb_gso_segment);
2402 /* Take action when hardware reception checksum errors are detected. */
2404 void netdev_rx_csum_fault(struct net_device *dev)
2406 if (net_ratelimit()) {
2407 pr_err("%s: hw csum failure\n", dev ? dev->name : "<unknown>");
2411 EXPORT_SYMBOL(netdev_rx_csum_fault);
2414 /* Actually, we should eliminate this check as soon as we know, that:
2415 * 1. IOMMU is present and allows to map all the memory.
2416 * 2. No high memory really exists on this machine.
2419 static int illegal_highdma(struct net_device *dev, struct sk_buff *skb)
2421 #ifdef CONFIG_HIGHMEM
2423 if (!(dev->features & NETIF_F_HIGHDMA)) {
2424 for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
2425 skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
2426 if (PageHighMem(skb_frag_page(frag)))
2431 if (PCI_DMA_BUS_IS_PHYS) {
2432 struct device *pdev = dev->dev.parent;
2436 for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
2437 skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
2438 dma_addr_t addr = page_to_phys(skb_frag_page(frag));
2439 if (!pdev->dma_mask || addr + PAGE_SIZE - 1 > *pdev->dma_mask)
2448 void (*destructor)(struct sk_buff *skb);
2451 #define DEV_GSO_CB(skb) ((struct dev_gso_cb *)(skb)->cb)
2453 static void dev_gso_skb_destructor(struct sk_buff *skb)
2455 struct dev_gso_cb *cb;
2457 kfree_skb_list(skb->next);
2460 cb = DEV_GSO_CB(skb);
2462 cb->destructor(skb);
2466 * dev_gso_segment - Perform emulated hardware segmentation on skb.
2467 * @skb: buffer to segment
2468 * @features: device features as applicable to this skb
2470 * This function segments the given skb and stores the list of segments
2473 static int dev_gso_segment(struct sk_buff *skb, netdev_features_t features)
2475 struct sk_buff *segs;
2477 segs = skb_gso_segment(skb, features);
2479 /* Verifying header integrity only. */
2484 return PTR_ERR(segs);
2487 DEV_GSO_CB(skb)->destructor = skb->destructor;
2488 skb->destructor = dev_gso_skb_destructor;
2493 static netdev_features_t harmonize_features(struct sk_buff *skb,
2494 netdev_features_t features)
2496 if (skb->ip_summed != CHECKSUM_NONE &&
2497 !can_checksum_protocol(features, skb_network_protocol(skb))) {
2498 features &= ~NETIF_F_ALL_CSUM;
2499 } else if (illegal_highdma(skb->dev, skb)) {
2500 features &= ~NETIF_F_SG;
2506 netdev_features_t netif_skb_features(struct sk_buff *skb)
2508 __be16 protocol = skb->protocol;
2509 netdev_features_t features = skb->dev->features;
2511 if (skb_shinfo(skb)->gso_segs > skb->dev->gso_max_segs)
2512 features &= ~NETIF_F_GSO_MASK;
2514 if (protocol == htons(ETH_P_8021Q) || protocol == htons(ETH_P_8021AD)) {
2515 struct vlan_ethhdr *veh = (struct vlan_ethhdr *)skb->data;
2516 protocol = veh->h_vlan_encapsulated_proto;
2517 } else if (!vlan_tx_tag_present(skb)) {
2518 return harmonize_features(skb, features);
2521 features &= (skb->dev->vlan_features | NETIF_F_HW_VLAN_CTAG_TX |
2522 NETIF_F_HW_VLAN_STAG_TX);
2524 if (protocol == htons(ETH_P_8021Q) || protocol == htons(ETH_P_8021AD))
2525 features &= NETIF_F_SG | NETIF_F_HIGHDMA | NETIF_F_FRAGLIST |
2526 NETIF_F_GEN_CSUM | NETIF_F_HW_VLAN_CTAG_TX |
2527 NETIF_F_HW_VLAN_STAG_TX;
2529 return harmonize_features(skb, features);
2531 EXPORT_SYMBOL(netif_skb_features);
2533 int dev_hard_start_xmit(struct sk_buff *skb, struct net_device *dev,
2534 struct netdev_queue *txq, void *accel_priv)
2536 const struct net_device_ops *ops = dev->netdev_ops;
2537 int rc = NETDEV_TX_OK;
2538 unsigned int skb_len;
2540 if (likely(!skb->next)) {
2541 netdev_features_t features;
2544 * If device doesn't need skb->dst, release it right now while
2545 * its hot in this cpu cache
2547 if (dev->priv_flags & IFF_XMIT_DST_RELEASE)
2550 features = netif_skb_features(skb);
2552 if (vlan_tx_tag_present(skb) &&
2553 !vlan_hw_offload_capable(features, skb->vlan_proto)) {
2554 skb = __vlan_put_tag(skb, skb->vlan_proto,
2555 vlan_tx_tag_get(skb));
2562 /* If encapsulation offload request, verify we are testing
2563 * hardware encapsulation features instead of standard
2564 * features for the netdev
2566 if (skb->encapsulation)
2567 features &= dev->hw_enc_features;
2569 if (netif_needs_gso(skb, features)) {
2570 if (unlikely(dev_gso_segment(skb, features)))
2575 if (skb_needs_linearize(skb, features) &&
2576 __skb_linearize(skb))
2579 /* If packet is not checksummed and device does not
2580 * support checksumming for this protocol, complete
2581 * checksumming here.
2583 if (skb->ip_summed == CHECKSUM_PARTIAL) {
2584 if (skb->encapsulation)
2585 skb_set_inner_transport_header(skb,
2586 skb_checksum_start_offset(skb));
2588 skb_set_transport_header(skb,
2589 skb_checksum_start_offset(skb));
2590 if (!(features & NETIF_F_ALL_CSUM) &&
2591 skb_checksum_help(skb))
2596 if (!list_empty(&ptype_all))
2597 dev_queue_xmit_nit(skb, dev);
2601 rc = ops->ndo_dfwd_start_xmit(skb, dev, accel_priv);
2603 rc = ops->ndo_start_xmit(skb, dev);
2605 trace_net_dev_xmit(skb, rc, dev, skb_len);
2606 if (rc == NETDEV_TX_OK && txq)
2607 txq_trans_update(txq);
2613 struct sk_buff *nskb = skb->next;
2615 skb->next = nskb->next;
2618 if (!list_empty(&ptype_all))
2619 dev_queue_xmit_nit(nskb, dev);
2621 skb_len = nskb->len;
2623 rc = ops->ndo_dfwd_start_xmit(nskb, dev, accel_priv);
2625 rc = ops->ndo_start_xmit(nskb, dev);
2626 trace_net_dev_xmit(nskb, rc, dev, skb_len);
2627 if (unlikely(rc != NETDEV_TX_OK)) {
2628 if (rc & ~NETDEV_TX_MASK)
2629 goto out_kfree_gso_skb;
2630 nskb->next = skb->next;
2634 txq_trans_update(txq);
2635 if (unlikely(netif_xmit_stopped(txq) && skb->next))
2636 return NETDEV_TX_BUSY;
2637 } while (skb->next);
2640 if (likely(skb->next == NULL)) {
2641 skb->destructor = DEV_GSO_CB(skb)->destructor;
2650 EXPORT_SYMBOL_GPL(dev_hard_start_xmit);
2652 static void qdisc_pkt_len_init(struct sk_buff *skb)
2654 const struct skb_shared_info *shinfo = skb_shinfo(skb);
2656 qdisc_skb_cb(skb)->pkt_len = skb->len;
2658 /* To get more precise estimation of bytes sent on wire,
2659 * we add to pkt_len the headers size of all segments
2661 if (shinfo->gso_size) {
2662 unsigned int hdr_len;
2663 u16 gso_segs = shinfo->gso_segs;
2665 /* mac layer + network layer */
2666 hdr_len = skb_transport_header(skb) - skb_mac_header(skb);
2668 /* + transport layer */
2669 if (likely(shinfo->gso_type & (SKB_GSO_TCPV4 | SKB_GSO_TCPV6)))
2670 hdr_len += tcp_hdrlen(skb);
2672 hdr_len += sizeof(struct udphdr);
2674 if (shinfo->gso_type & SKB_GSO_DODGY)
2675 gso_segs = DIV_ROUND_UP(skb->len - hdr_len,
2678 qdisc_skb_cb(skb)->pkt_len += (gso_segs - 1) * hdr_len;
2682 static inline int __dev_xmit_skb(struct sk_buff *skb, struct Qdisc *q,
2683 struct net_device *dev,
2684 struct netdev_queue *txq)
2686 spinlock_t *root_lock = qdisc_lock(q);
2690 qdisc_pkt_len_init(skb);
2691 qdisc_calculate_pkt_len(skb, q);
2693 * Heuristic to force contended enqueues to serialize on a
2694 * separate lock before trying to get qdisc main lock.
2695 * This permits __QDISC_STATE_RUNNING owner to get the lock more often
2696 * and dequeue packets faster.
2698 contended = qdisc_is_running(q);
2699 if (unlikely(contended))
2700 spin_lock(&q->busylock);
2702 spin_lock(root_lock);
2703 if (unlikely(test_bit(__QDISC_STATE_DEACTIVATED, &q->state))) {
2706 } else if ((q->flags & TCQ_F_CAN_BYPASS) && !qdisc_qlen(q) &&
2707 qdisc_run_begin(q)) {
2709 * This is a work-conserving queue; there are no old skbs
2710 * waiting to be sent out; and the qdisc is not running -
2711 * xmit the skb directly.
2713 if (!(dev->priv_flags & IFF_XMIT_DST_RELEASE))
2716 qdisc_bstats_update(q, skb);
2718 if (sch_direct_xmit(skb, q, dev, txq, root_lock)) {
2719 if (unlikely(contended)) {
2720 spin_unlock(&q->busylock);
2727 rc = NET_XMIT_SUCCESS;
2730 rc = q->enqueue(skb, q) & NET_XMIT_MASK;
2731 if (qdisc_run_begin(q)) {
2732 if (unlikely(contended)) {
2733 spin_unlock(&q->busylock);
2739 spin_unlock(root_lock);
2740 if (unlikely(contended))
2741 spin_unlock(&q->busylock);
2745 #if IS_ENABLED(CONFIG_NETPRIO_CGROUP)
2746 static void skb_update_prio(struct sk_buff *skb)
2748 struct netprio_map *map = rcu_dereference_bh(skb->dev->priomap);
2750 if (!skb->priority && skb->sk && map) {
2751 unsigned int prioidx = skb->sk->sk_cgrp_prioidx;
2753 if (prioidx < map->priomap_len)
2754 skb->priority = map->priomap[prioidx];
2758 #define skb_update_prio(skb)
2761 static DEFINE_PER_CPU(int, xmit_recursion);
2762 #define RECURSION_LIMIT 10
2765 * dev_loopback_xmit - loop back @skb
2766 * @skb: buffer to transmit
2768 int dev_loopback_xmit(struct sk_buff *skb)
2770 skb_reset_mac_header(skb);
2771 __skb_pull(skb, skb_network_offset(skb));
2772 skb->pkt_type = PACKET_LOOPBACK;
2773 skb->ip_summed = CHECKSUM_UNNECESSARY;
2774 WARN_ON(!skb_dst(skb));
2779 EXPORT_SYMBOL(dev_loopback_xmit);
2782 * dev_queue_xmit - transmit a buffer
2783 * @skb: buffer to transmit
2785 * Queue a buffer for transmission to a network device. The caller must
2786 * have set the device and priority and built the buffer before calling
2787 * this function. The function can be called from an interrupt.
2789 * A negative errno code is returned on a failure. A success does not
2790 * guarantee the frame will be transmitted as it may be dropped due
2791 * to congestion or traffic shaping.
2793 * -----------------------------------------------------------------------------------
2794 * I notice this method can also return errors from the queue disciplines,
2795 * including NET_XMIT_DROP, which is a positive value. So, errors can also
2798 * Regardless of the return value, the skb is consumed, so it is currently
2799 * difficult to retry a send to this method. (You can bump the ref count
2800 * before sending to hold a reference for retry if you are careful.)
2802 * When calling this method, interrupts MUST be enabled. This is because
2803 * the BH enable code must have IRQs enabled so that it will not deadlock.
2806 int dev_queue_xmit(struct sk_buff *skb)
2808 struct net_device *dev = skb->dev;
2809 struct netdev_queue *txq;
2813 skb_reset_mac_header(skb);
2815 /* Disable soft irqs for various locks below. Also
2816 * stops preemption for RCU.
2820 skb_update_prio(skb);
2822 txq = netdev_pick_tx(dev, skb);
2823 q = rcu_dereference_bh(txq->qdisc);
2825 #ifdef CONFIG_NET_CLS_ACT
2826 skb->tc_verd = SET_TC_AT(skb->tc_verd, AT_EGRESS);
2828 trace_net_dev_queue(skb);
2830 rc = __dev_xmit_skb(skb, q, dev, txq);
2834 /* The device has no queue. Common case for software devices:
2835 loopback, all the sorts of tunnels...
2837 Really, it is unlikely that netif_tx_lock protection is necessary
2838 here. (f.e. loopback and IP tunnels are clean ignoring statistics
2840 However, it is possible, that they rely on protection
2843 Check this and shot the lock. It is not prone from deadlocks.
2844 Either shot noqueue qdisc, it is even simpler 8)
2846 if (dev->flags & IFF_UP) {
2847 int cpu = smp_processor_id(); /* ok because BHs are off */
2849 if (txq->xmit_lock_owner != cpu) {
2851 if (__this_cpu_read(xmit_recursion) > RECURSION_LIMIT)
2852 goto recursion_alert;
2854 HARD_TX_LOCK(dev, txq, cpu);
2856 if (!netif_xmit_stopped(txq)) {
2857 __this_cpu_inc(xmit_recursion);
2858 rc = dev_hard_start_xmit(skb, dev, txq, NULL);
2859 __this_cpu_dec(xmit_recursion);
2860 if (dev_xmit_complete(rc)) {
2861 HARD_TX_UNLOCK(dev, txq);
2865 HARD_TX_UNLOCK(dev, txq);
2866 net_crit_ratelimited("Virtual device %s asks to queue packet!\n",
2869 /* Recursion is detected! It is possible,
2873 net_crit_ratelimited("Dead loop on virtual device %s, fix it urgently!\n",
2879 rcu_read_unlock_bh();
2884 rcu_read_unlock_bh();
2887 EXPORT_SYMBOL(dev_queue_xmit);
2890 /*=======================================================================
2892 =======================================================================*/
2894 int netdev_max_backlog __read_mostly = 1000;
2895 EXPORT_SYMBOL(netdev_max_backlog);
2897 int netdev_tstamp_prequeue __read_mostly = 1;
2898 int netdev_budget __read_mostly = 300;
2899 int weight_p __read_mostly = 64; /* old backlog weight */
2901 /* Called with irq disabled */
2902 static inline void ____napi_schedule(struct softnet_data *sd,
2903 struct napi_struct *napi)
2905 list_add_tail(&napi->poll_list, &sd->poll_list);
2906 __raise_softirq_irqoff(NET_RX_SOFTIRQ);
2911 /* One global table that all flow-based protocols share. */
2912 struct rps_sock_flow_table __rcu *rps_sock_flow_table __read_mostly;
2913 EXPORT_SYMBOL(rps_sock_flow_table);
2915 struct static_key rps_needed __read_mostly;
2917 static struct rps_dev_flow *
2918 set_rps_cpu(struct net_device *dev, struct sk_buff *skb,
2919 struct rps_dev_flow *rflow, u16 next_cpu)
2921 if (next_cpu != RPS_NO_CPU) {
2922 #ifdef CONFIG_RFS_ACCEL
2923 struct netdev_rx_queue *rxqueue;
2924 struct rps_dev_flow_table *flow_table;
2925 struct rps_dev_flow *old_rflow;
2930 /* Should we steer this flow to a different hardware queue? */
2931 if (!skb_rx_queue_recorded(skb) || !dev->rx_cpu_rmap ||
2932 !(dev->features & NETIF_F_NTUPLE))
2934 rxq_index = cpu_rmap_lookup_index(dev->rx_cpu_rmap, next_cpu);
2935 if (rxq_index == skb_get_rx_queue(skb))
2938 rxqueue = dev->_rx + rxq_index;
2939 flow_table = rcu_dereference(rxqueue->rps_flow_table);
2942 flow_id = skb->rxhash & flow_table->mask;
2943 rc = dev->netdev_ops->ndo_rx_flow_steer(dev, skb,
2944 rxq_index, flow_id);
2948 rflow = &flow_table->flows[flow_id];
2950 if (old_rflow->filter == rflow->filter)
2951 old_rflow->filter = RPS_NO_FILTER;
2955 per_cpu(softnet_data, next_cpu).input_queue_head;
2958 rflow->cpu = next_cpu;
2963 * get_rps_cpu is called from netif_receive_skb and returns the target
2964 * CPU from the RPS map of the receiving queue for a given skb.
2965 * rcu_read_lock must be held on entry.
2967 static int get_rps_cpu(struct net_device *dev, struct sk_buff *skb,
2968 struct rps_dev_flow **rflowp)
2970 struct netdev_rx_queue *rxqueue;
2971 struct rps_map *map;
2972 struct rps_dev_flow_table *flow_table;
2973 struct rps_sock_flow_table *sock_flow_table;
2977 if (skb_rx_queue_recorded(skb)) {
2978 u16 index = skb_get_rx_queue(skb);
2979 if (unlikely(index >= dev->real_num_rx_queues)) {
2980 WARN_ONCE(dev->real_num_rx_queues > 1,
2981 "%s received packet on queue %u, but number "
2982 "of RX queues is %u\n",
2983 dev->name, index, dev->real_num_rx_queues);
2986 rxqueue = dev->_rx + index;
2990 map = rcu_dereference(rxqueue->rps_map);
2992 if (map->len == 1 &&
2993 !rcu_access_pointer(rxqueue->rps_flow_table)) {
2994 tcpu = map->cpus[0];
2995 if (cpu_online(tcpu))
2999 } else if (!rcu_access_pointer(rxqueue->rps_flow_table)) {
3003 skb_reset_network_header(skb);
3004 if (!skb_get_hash(skb))
3007 flow_table = rcu_dereference(rxqueue->rps_flow_table);
3008 sock_flow_table = rcu_dereference(rps_sock_flow_table);
3009 if (flow_table && sock_flow_table) {
3011 struct rps_dev_flow *rflow;
3013 rflow = &flow_table->flows[skb->rxhash & flow_table->mask];
3016 next_cpu = sock_flow_table->ents[skb->rxhash &
3017 sock_flow_table->mask];
3020 * If the desired CPU (where last recvmsg was done) is
3021 * different from current CPU (one in the rx-queue flow
3022 * table entry), switch if one of the following holds:
3023 * - Current CPU is unset (equal to RPS_NO_CPU).
3024 * - Current CPU is offline.
3025 * - The current CPU's queue tail has advanced beyond the
3026 * last packet that was enqueued using this table entry.
3027 * This guarantees that all previous packets for the flow
3028 * have been dequeued, thus preserving in order delivery.
3030 if (unlikely(tcpu != next_cpu) &&
3031 (tcpu == RPS_NO_CPU || !cpu_online(tcpu) ||
3032 ((int)(per_cpu(softnet_data, tcpu).input_queue_head -
3033 rflow->last_qtail)) >= 0)) {
3035 rflow = set_rps_cpu(dev, skb, rflow, next_cpu);
3038 if (tcpu != RPS_NO_CPU && cpu_online(tcpu)) {
3046 tcpu = map->cpus[((u64) skb->rxhash * map->len) >> 32];
3048 if (cpu_online(tcpu)) {
3058 #ifdef CONFIG_RFS_ACCEL
3061 * rps_may_expire_flow - check whether an RFS hardware filter may be removed
3062 * @dev: Device on which the filter was set
3063 * @rxq_index: RX queue index
3064 * @flow_id: Flow ID passed to ndo_rx_flow_steer()
3065 * @filter_id: Filter ID returned by ndo_rx_flow_steer()
3067 * Drivers that implement ndo_rx_flow_steer() should periodically call
3068 * this function for each installed filter and remove the filters for
3069 * which it returns %true.
3071 bool rps_may_expire_flow(struct net_device *dev, u16 rxq_index,
3072 u32 flow_id, u16 filter_id)
3074 struct netdev_rx_queue *rxqueue = dev->_rx + rxq_index;
3075 struct rps_dev_flow_table *flow_table;
3076 struct rps_dev_flow *rflow;
3081 flow_table = rcu_dereference(rxqueue->rps_flow_table);
3082 if (flow_table && flow_id <= flow_table->mask) {
3083 rflow = &flow_table->flows[flow_id];
3084 cpu = ACCESS_ONCE(rflow->cpu);
3085 if (rflow->filter == filter_id && cpu != RPS_NO_CPU &&
3086 ((int)(per_cpu(softnet_data, cpu).input_queue_head -
3087 rflow->last_qtail) <
3088 (int)(10 * flow_table->mask)))
3094 EXPORT_SYMBOL(rps_may_expire_flow);
3096 #endif /* CONFIG_RFS_ACCEL */
3098 /* Called from hardirq (IPI) context */
3099 static void rps_trigger_softirq(void *data)
3101 struct softnet_data *sd = data;
3103 ____napi_schedule(sd, &sd->backlog);
3107 #endif /* CONFIG_RPS */
3110 * Check if this softnet_data structure is another cpu one
3111 * If yes, queue it to our IPI list and return 1
3114 static int rps_ipi_queued(struct softnet_data *sd)
3117 struct softnet_data *mysd = &__get_cpu_var(softnet_data);
3120 sd->rps_ipi_next = mysd->rps_ipi_list;
3121 mysd->rps_ipi_list = sd;
3123 __raise_softirq_irqoff(NET_RX_SOFTIRQ);
3126 #endif /* CONFIG_RPS */
3130 #ifdef CONFIG_NET_FLOW_LIMIT
3131 int netdev_flow_limit_table_len __read_mostly = (1 << 12);
3134 static bool skb_flow_limit(struct sk_buff *skb, unsigned int qlen)
3136 #ifdef CONFIG_NET_FLOW_LIMIT
3137 struct sd_flow_limit *fl;
3138 struct softnet_data *sd;
3139 unsigned int old_flow, new_flow;
3141 if (qlen < (netdev_max_backlog >> 1))
3144 sd = &__get_cpu_var(softnet_data);
3147 fl = rcu_dereference(sd->flow_limit);
3149 new_flow = skb_get_hash(skb) & (fl->num_buckets - 1);
3150 old_flow = fl->history[fl->history_head];
3151 fl->history[fl->history_head] = new_flow;
3154 fl->history_head &= FLOW_LIMIT_HISTORY - 1;
3156 if (likely(fl->buckets[old_flow]))
3157 fl->buckets[old_flow]--;
3159 if (++fl->buckets[new_flow] > (FLOW_LIMIT_HISTORY >> 1)) {
3171 * enqueue_to_backlog is called to queue an skb to a per CPU backlog
3172 * queue (may be a remote CPU queue).
3174 static int enqueue_to_backlog(struct sk_buff *skb, int cpu,
3175 unsigned int *qtail)
3177 struct softnet_data *sd;
3178 unsigned long flags;
3181 sd = &per_cpu(softnet_data, cpu);
3183 local_irq_save(flags);
3186 qlen = skb_queue_len(&sd->input_pkt_queue);
3187 if (qlen <= netdev_max_backlog && !skb_flow_limit(skb, qlen)) {
3188 if (skb_queue_len(&sd->input_pkt_queue)) {
3190 __skb_queue_tail(&sd->input_pkt_queue, skb);
3191 input_queue_tail_incr_save(sd, qtail);
3193 local_irq_restore(flags);
3194 return NET_RX_SUCCESS;
3197 /* Schedule NAPI for backlog device
3198 * We can use non atomic operation since we own the queue lock
3200 if (!__test_and_set_bit(NAPI_STATE_SCHED, &sd->backlog.state)) {
3201 if (!rps_ipi_queued(sd))
3202 ____napi_schedule(sd, &sd->backlog);
3210 local_irq_restore(flags);
3212 atomic_long_inc(&skb->dev->rx_dropped);
3218 * netif_rx - post buffer to the network code
3219 * @skb: buffer to post
3221 * This function receives a packet from a device driver and queues it for
3222 * the upper (protocol) levels to process. It always succeeds. The buffer
3223 * may be dropped during processing for congestion control or by the
3227 * NET_RX_SUCCESS (no congestion)
3228 * NET_RX_DROP (packet was dropped)
3232 int netif_rx(struct sk_buff *skb)
3236 /* if netpoll wants it, pretend we never saw it */
3237 if (netpoll_rx(skb))
3240 net_timestamp_check(netdev_tstamp_prequeue, skb);
3242 trace_netif_rx(skb);
3244 if (static_key_false(&rps_needed)) {
3245 struct rps_dev_flow voidflow, *rflow = &voidflow;
3251 cpu = get_rps_cpu(skb->dev, skb, &rflow);
3253 cpu = smp_processor_id();
3255 ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail);
3263 ret = enqueue_to_backlog(skb, get_cpu(), &qtail);
3268 EXPORT_SYMBOL(netif_rx);
3270 int netif_rx_ni(struct sk_buff *skb)
3275 err = netif_rx(skb);
3276 if (local_softirq_pending())
3282 EXPORT_SYMBOL(netif_rx_ni);
3284 static void net_tx_action(struct softirq_action *h)
3286 struct softnet_data *sd = &__get_cpu_var(softnet_data);
3288 if (sd->completion_queue) {
3289 struct sk_buff *clist;
3291 local_irq_disable();
3292 clist = sd->completion_queue;
3293 sd->completion_queue = NULL;
3297 struct sk_buff *skb = clist;
3298 clist = clist->next;
3300 WARN_ON(atomic_read(&skb->users));
3301 if (likely(get_kfree_skb_cb(skb)->reason == SKB_REASON_CONSUMED))
3302 trace_consume_skb(skb);
3304 trace_kfree_skb(skb, net_tx_action);
3309 if (sd->output_queue) {
3312 local_irq_disable();
3313 head = sd->output_queue;
3314 sd->output_queue = NULL;
3315 sd->output_queue_tailp = &sd->output_queue;
3319 struct Qdisc *q = head;
3320 spinlock_t *root_lock;
3322 head = head->next_sched;
3324 root_lock = qdisc_lock(q);
3325 if (spin_trylock(root_lock)) {
3326 smp_mb__before_clear_bit();
3327 clear_bit(__QDISC_STATE_SCHED,
3330 spin_unlock(root_lock);
3332 if (!test_bit(__QDISC_STATE_DEACTIVATED,
3334 __netif_reschedule(q);
3336 smp_mb__before_clear_bit();
3337 clear_bit(__QDISC_STATE_SCHED,
3345 #if (defined(CONFIG_BRIDGE) || defined(CONFIG_BRIDGE_MODULE)) && \
3346 (defined(CONFIG_ATM_LANE) || defined(CONFIG_ATM_LANE_MODULE))
3347 /* This hook is defined here for ATM LANE */
3348 int (*br_fdb_test_addr_hook)(struct net_device *dev,
3349 unsigned char *addr) __read_mostly;
3350 EXPORT_SYMBOL_GPL(br_fdb_test_addr_hook);
3353 #ifdef CONFIG_NET_CLS_ACT
3354 /* TODO: Maybe we should just force sch_ingress to be compiled in
3355 * when CONFIG_NET_CLS_ACT is? otherwise some useless instructions
3356 * a compare and 2 stores extra right now if we dont have it on
3357 * but have CONFIG_NET_CLS_ACT
3358 * NOTE: This doesn't stop any functionality; if you dont have
3359 * the ingress scheduler, you just can't add policies on ingress.
3362 static int ing_filter(struct sk_buff *skb, struct netdev_queue *rxq)
3364 struct net_device *dev = skb->dev;
3365 u32 ttl = G_TC_RTTL(skb->tc_verd);
3366 int result = TC_ACT_OK;
3369 if (unlikely(MAX_RED_LOOP < ttl++)) {
3370 net_warn_ratelimited("Redir loop detected Dropping packet (%d->%d)\n",
3371 skb->skb_iif, dev->ifindex);
3375 skb->tc_verd = SET_TC_RTTL(skb->tc_verd, ttl);
3376 skb->tc_verd = SET_TC_AT(skb->tc_verd, AT_INGRESS);
3379 if (q != &noop_qdisc) {
3380 spin_lock(qdisc_lock(q));
3381 if (likely(!test_bit(__QDISC_STATE_DEACTIVATED, &q->state)))
3382 result = qdisc_enqueue_root(skb, q);
3383 spin_unlock(qdisc_lock(q));
3389 static inline struct sk_buff *handle_ing(struct sk_buff *skb,
3390 struct packet_type **pt_prev,
3391 int *ret, struct net_device *orig_dev)
3393 struct netdev_queue *rxq = rcu_dereference(skb->dev->ingress_queue);
3395 if (!rxq || rxq->qdisc == &noop_qdisc)
3399 *ret = deliver_skb(skb, *pt_prev, orig_dev);
3403 switch (ing_filter(skb, rxq)) {
3417 * netdev_rx_handler_register - register receive handler
3418 * @dev: device to register a handler for
3419 * @rx_handler: receive handler to register
3420 * @rx_handler_data: data pointer that is used by rx handler
3422 * Register a receive hander for a device. This handler will then be
3423 * called from __netif_receive_skb. A negative errno code is returned
3426 * The caller must hold the rtnl_mutex.
3428 * For a general description of rx_handler, see enum rx_handler_result.
3430 int netdev_rx_handler_register(struct net_device *dev,
3431 rx_handler_func_t *rx_handler,
3432 void *rx_handler_data)
3436 if (dev->rx_handler)
3439 /* Note: rx_handler_data must be set before rx_handler */
3440 rcu_assign_pointer(dev->rx_handler_data, rx_handler_data);
3441 rcu_assign_pointer(dev->rx_handler, rx_handler);
3445 EXPORT_SYMBOL_GPL(netdev_rx_handler_register);
3448 * netdev_rx_handler_unregister - unregister receive handler
3449 * @dev: device to unregister a handler from
3451 * Unregister a receive handler from a device.
3453 * The caller must hold the rtnl_mutex.
3455 void netdev_rx_handler_unregister(struct net_device *dev)
3459 RCU_INIT_POINTER(dev->rx_handler, NULL);
3460 /* a reader seeing a non NULL rx_handler in a rcu_read_lock()
3461 * section has a guarantee to see a non NULL rx_handler_data
3465 RCU_INIT_POINTER(dev->rx_handler_data, NULL);
3467 EXPORT_SYMBOL_GPL(netdev_rx_handler_unregister);
3470 * Limit the use of PFMEMALLOC reserves to those protocols that implement
3471 * the special handling of PFMEMALLOC skbs.
3473 static bool skb_pfmemalloc_protocol(struct sk_buff *skb)
3475 switch (skb->protocol) {
3476 case __constant_htons(ETH_P_ARP):
3477 case __constant_htons(ETH_P_IP):
3478 case __constant_htons(ETH_P_IPV6):
3479 case __constant_htons(ETH_P_8021Q):
3480 case __constant_htons(ETH_P_8021AD):
3487 static int __netif_receive_skb_core(struct sk_buff *skb, bool pfmemalloc)
3489 struct packet_type *ptype, *pt_prev;
3490 rx_handler_func_t *rx_handler;
3491 struct net_device *orig_dev;
3492 struct net_device *null_or_dev;
3493 bool deliver_exact = false;
3494 int ret = NET_RX_DROP;
3497 net_timestamp_check(!netdev_tstamp_prequeue, skb);
3499 trace_netif_receive_skb(skb);
3501 /* if we've gotten here through NAPI, check netpoll */
3502 if (netpoll_receive_skb(skb))
3505 orig_dev = skb->dev;
3507 skb_reset_network_header(skb);
3508 if (!skb_transport_header_was_set(skb))
3509 skb_reset_transport_header(skb);
3510 skb_reset_mac_len(skb);
3517 skb->skb_iif = skb->dev->ifindex;
3519 __this_cpu_inc(softnet_data.processed);
3521 if (skb->protocol == cpu_to_be16(ETH_P_8021Q) ||
3522 skb->protocol == cpu_to_be16(ETH_P_8021AD)) {
3523 skb = vlan_untag(skb);
3528 #ifdef CONFIG_NET_CLS_ACT
3529 if (skb->tc_verd & TC_NCLS) {
3530 skb->tc_verd = CLR_TC_NCLS(skb->tc_verd);
3538 list_for_each_entry_rcu(ptype, &ptype_all, list) {
3539 if (!ptype->dev || ptype->dev == skb->dev) {
3541 ret = deliver_skb(skb, pt_prev, orig_dev);
3547 #ifdef CONFIG_NET_CLS_ACT
3548 skb = handle_ing(skb, &pt_prev, &ret, orig_dev);
3554 if (pfmemalloc && !skb_pfmemalloc_protocol(skb))
3557 if (vlan_tx_tag_present(skb)) {
3559 ret = deliver_skb(skb, pt_prev, orig_dev);
3562 if (vlan_do_receive(&skb))
3564 else if (unlikely(!skb))
3568 rx_handler = rcu_dereference(skb->dev->rx_handler);
3571 ret = deliver_skb(skb, pt_prev, orig_dev);
3574 switch (rx_handler(&skb)) {
3575 case RX_HANDLER_CONSUMED:
3576 ret = NET_RX_SUCCESS;
3578 case RX_HANDLER_ANOTHER:
3580 case RX_HANDLER_EXACT:
3581 deliver_exact = true;
3582 case RX_HANDLER_PASS:
3589 if (unlikely(vlan_tx_tag_present(skb))) {
3590 if (vlan_tx_tag_get_id(skb))
3591 skb->pkt_type = PACKET_OTHERHOST;
3592 /* Note: we might in the future use prio bits
3593 * and set skb->priority like in vlan_do_receive()
3594 * For the time being, just ignore Priority Code Point
3599 /* deliver only exact match when indicated */
3600 null_or_dev = deliver_exact ? skb->dev : NULL;
3602 type = skb->protocol;
3603 list_for_each_entry_rcu(ptype,
3604 &ptype_base[ntohs(type) & PTYPE_HASH_MASK], list) {
3605 if (ptype->type == type &&
3606 (ptype->dev == null_or_dev || ptype->dev == skb->dev ||
3607 ptype->dev == orig_dev)) {
3609 ret = deliver_skb(skb, pt_prev, orig_dev);
3615 if (unlikely(skb_orphan_frags(skb, GFP_ATOMIC)))
3618 ret = pt_prev->func(skb, skb->dev, pt_prev, orig_dev);
3621 atomic_long_inc(&skb->dev->rx_dropped);
3623 /* Jamal, now you will not able to escape explaining
3624 * me how you were going to use this. :-)
3635 static int __netif_receive_skb(struct sk_buff *skb)
3639 if (sk_memalloc_socks() && skb_pfmemalloc(skb)) {
3640 unsigned long pflags = current->flags;
3643 * PFMEMALLOC skbs are special, they should
3644 * - be delivered to SOCK_MEMALLOC sockets only
3645 * - stay away from userspace
3646 * - have bounded memory usage
3648 * Use PF_MEMALLOC as this saves us from propagating the allocation
3649 * context down to all allocation sites.
3651 current->flags |= PF_MEMALLOC;
3652 ret = __netif_receive_skb_core(skb, true);
3653 tsk_restore_flags(current, pflags, PF_MEMALLOC);
3655 ret = __netif_receive_skb_core(skb, false);
3661 * netif_receive_skb - process receive buffer from network
3662 * @skb: buffer to process
3664 * netif_receive_skb() is the main receive data processing function.
3665 * It always succeeds. The buffer may be dropped during processing
3666 * for congestion control or by the protocol layers.
3668 * This function may only be called from softirq context and interrupts
3669 * should be enabled.
3671 * Return values (usually ignored):
3672 * NET_RX_SUCCESS: no congestion
3673 * NET_RX_DROP: packet was dropped
3675 int netif_receive_skb(struct sk_buff *skb)
3677 net_timestamp_check(netdev_tstamp_prequeue, skb);
3679 if (skb_defer_rx_timestamp(skb))
3680 return NET_RX_SUCCESS;
3683 if (static_key_false(&rps_needed)) {
3684 struct rps_dev_flow voidflow, *rflow = &voidflow;
3689 cpu = get_rps_cpu(skb->dev, skb, &rflow);
3692 ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail);
3699 return __netif_receive_skb(skb);
3701 EXPORT_SYMBOL(netif_receive_skb);
3703 /* Network device is going away, flush any packets still pending
3704 * Called with irqs disabled.
3706 static void flush_backlog(void *arg)
3708 struct net_device *dev = arg;
3709 struct softnet_data *sd = &__get_cpu_var(softnet_data);
3710 struct sk_buff *skb, *tmp;
3713 skb_queue_walk_safe(&sd->input_pkt_queue, skb, tmp) {
3714 if (skb->dev == dev) {
3715 __skb_unlink(skb, &sd->input_pkt_queue);
3717 input_queue_head_incr(sd);
3722 skb_queue_walk_safe(&sd->process_queue, skb, tmp) {
3723 if (skb->dev == dev) {
3724 __skb_unlink(skb, &sd->process_queue);
3726 input_queue_head_incr(sd);
3731 static int napi_gro_complete(struct sk_buff *skb)
3733 struct packet_offload *ptype;
3734 __be16 type = skb->protocol;
3735 struct list_head *head = &offload_base;
3738 BUILD_BUG_ON(sizeof(struct napi_gro_cb) > sizeof(skb->cb));
3740 if (NAPI_GRO_CB(skb)->count == 1) {
3741 skb_shinfo(skb)->gso_size = 0;
3746 list_for_each_entry_rcu(ptype, head, list) {
3747 if (ptype->type != type || !ptype->callbacks.gro_complete)
3750 err = ptype->callbacks.gro_complete(skb, 0);
3756 WARN_ON(&ptype->list == head);
3758 return NET_RX_SUCCESS;
3762 return netif_receive_skb(skb);
3765 /* napi->gro_list contains packets ordered by age.
3766 * youngest packets at the head of it.
3767 * Complete skbs in reverse order to reduce latencies.
3769 void napi_gro_flush(struct napi_struct *napi, bool flush_old)
3771 struct sk_buff *skb, *prev = NULL;
3773 /* scan list and build reverse chain */
3774 for (skb = napi->gro_list; skb != NULL; skb = skb->next) {
3779 for (skb = prev; skb; skb = prev) {
3782 if (flush_old && NAPI_GRO_CB(skb)->age == jiffies)
3786 napi_gro_complete(skb);
3790 napi->gro_list = NULL;
3792 EXPORT_SYMBOL(napi_gro_flush);
3794 static void gro_list_prepare(struct napi_struct *napi, struct sk_buff *skb)
3797 unsigned int maclen = skb->dev->hard_header_len;
3799 for (p = napi->gro_list; p; p = p->next) {
3800 unsigned long diffs;
3802 diffs = (unsigned long)p->dev ^ (unsigned long)skb->dev;
3803 diffs |= p->vlan_tci ^ skb->vlan_tci;
3804 if (maclen == ETH_HLEN)
3805 diffs |= compare_ether_header(skb_mac_header(p),
3806 skb_gro_mac_header(skb));
3808 diffs = memcmp(skb_mac_header(p),
3809 skb_gro_mac_header(skb),
3811 NAPI_GRO_CB(p)->same_flow = !diffs;
3812 NAPI_GRO_CB(p)->flush = 0;
3816 static void skb_gro_reset_offset(struct sk_buff *skb)
3818 const struct skb_shared_info *pinfo = skb_shinfo(skb);
3819 const skb_frag_t *frag0 = &pinfo->frags[0];
3821 NAPI_GRO_CB(skb)->data_offset = 0;
3822 NAPI_GRO_CB(skb)->frag0 = NULL;
3823 NAPI_GRO_CB(skb)->frag0_len = 0;
3825 if (skb_mac_header(skb) == skb_tail_pointer(skb) &&
3827 !PageHighMem(skb_frag_page(frag0))) {
3828 NAPI_GRO_CB(skb)->frag0 = skb_frag_address(frag0);
3829 NAPI_GRO_CB(skb)->frag0_len = skb_frag_size(frag0);
3833 static enum gro_result dev_gro_receive(struct napi_struct *napi, struct sk_buff *skb)
3835 struct sk_buff **pp = NULL;
3836 struct packet_offload *ptype;
3837 __be16 type = skb->protocol;
3838 struct list_head *head = &offload_base;
3840 enum gro_result ret;
3842 if (!(skb->dev->features & NETIF_F_GRO) || netpoll_rx_on(skb))
3845 if (skb_is_gso(skb) || skb_has_frag_list(skb))
3848 skb_gro_reset_offset(skb);
3849 gro_list_prepare(napi, skb);
3852 list_for_each_entry_rcu(ptype, head, list) {
3853 if (ptype->type != type || !ptype->callbacks.gro_receive)
3856 skb_set_network_header(skb, skb_gro_offset(skb));
3857 skb_reset_mac_len(skb);
3858 NAPI_GRO_CB(skb)->same_flow = 0;
3859 NAPI_GRO_CB(skb)->flush = 0;
3860 NAPI_GRO_CB(skb)->free = 0;
3862 pp = ptype->callbacks.gro_receive(&napi->gro_list, skb);
3867 if (&ptype->list == head)
3870 same_flow = NAPI_GRO_CB(skb)->same_flow;
3871 ret = NAPI_GRO_CB(skb)->free ? GRO_MERGED_FREE : GRO_MERGED;
3874 struct sk_buff *nskb = *pp;
3878 napi_gro_complete(nskb);
3885 if (NAPI_GRO_CB(skb)->flush || napi->gro_count >= MAX_GRO_SKBS)
3889 NAPI_GRO_CB(skb)->count = 1;
3890 NAPI_GRO_CB(skb)->age = jiffies;
3891 skb_shinfo(skb)->gso_size = skb_gro_len(skb);
3892 skb->next = napi->gro_list;
3893 napi->gro_list = skb;
3897 if (skb_headlen(skb) < skb_gro_offset(skb)) {
3898 int grow = skb_gro_offset(skb) - skb_headlen(skb);
3900 BUG_ON(skb->end - skb->tail < grow);
3902 memcpy(skb_tail_pointer(skb), NAPI_GRO_CB(skb)->frag0, grow);
3905 skb->data_len -= grow;
3907 skb_shinfo(skb)->frags[0].page_offset += grow;
3908 skb_frag_size_sub(&skb_shinfo(skb)->frags[0], grow);
3910 if (unlikely(!skb_frag_size(&skb_shinfo(skb)->frags[0]))) {
3911 skb_frag_unref(skb, 0);
3912 memmove(skb_shinfo(skb)->frags,
3913 skb_shinfo(skb)->frags + 1,
3914 --skb_shinfo(skb)->nr_frags * sizeof(skb_frag_t));
3927 static gro_result_t napi_skb_finish(gro_result_t ret, struct sk_buff *skb)
3931 if (netif_receive_skb(skb))
3939 case GRO_MERGED_FREE:
3940 if (NAPI_GRO_CB(skb)->free == NAPI_GRO_FREE_STOLEN_HEAD)
3941 kmem_cache_free(skbuff_head_cache, skb);
3954 gro_result_t napi_gro_receive(struct napi_struct *napi, struct sk_buff *skb)
3956 return napi_skb_finish(dev_gro_receive(napi, skb), skb);
3958 EXPORT_SYMBOL(napi_gro_receive);
3960 static void napi_reuse_skb(struct napi_struct *napi, struct sk_buff *skb)
3962 __skb_pull(skb, skb_headlen(skb));
3963 /* restore the reserve we had after netdev_alloc_skb_ip_align() */
3964 skb_reserve(skb, NET_SKB_PAD + NET_IP_ALIGN - skb_headroom(skb));
3966 skb->dev = napi->dev;
3972 struct sk_buff *napi_get_frags(struct napi_struct *napi)
3974 struct sk_buff *skb = napi->skb;
3977 skb = netdev_alloc_skb_ip_align(napi->dev, GRO_MAX_HEAD);
3982 EXPORT_SYMBOL(napi_get_frags);
3984 static gro_result_t napi_frags_finish(struct napi_struct *napi, struct sk_buff *skb,
3989 if (netif_receive_skb(skb))
3994 case GRO_MERGED_FREE:
3995 napi_reuse_skb(napi, skb);
4006 static struct sk_buff *napi_frags_skb(struct napi_struct *napi)
4008 struct sk_buff *skb = napi->skb;
4012 if (unlikely(!pskb_may_pull(skb, sizeof(struct ethhdr)))) {
4013 napi_reuse_skb(napi, skb);
4016 skb->protocol = eth_type_trans(skb, skb->dev);
4021 gro_result_t napi_gro_frags(struct napi_struct *napi)
4023 struct sk_buff *skb = napi_frags_skb(napi);
4028 return napi_frags_finish(napi, skb, dev_gro_receive(napi, skb));
4030 EXPORT_SYMBOL(napi_gro_frags);
4033 * net_rps_action sends any pending IPI's for rps.
4034 * Note: called with local irq disabled, but exits with local irq enabled.
4036 static void net_rps_action_and_irq_enable(struct softnet_data *sd)
4039 struct softnet_data *remsd = sd->rps_ipi_list;
4042 sd->rps_ipi_list = NULL;
4046 /* Send pending IPI's to kick RPS processing on remote cpus. */
4048 struct softnet_data *next = remsd->rps_ipi_next;
4050 if (cpu_online(remsd->cpu))
4051 __smp_call_function_single(remsd->cpu,
4060 static int process_backlog(struct napi_struct *napi, int quota)
4063 struct softnet_data *sd = container_of(napi, struct softnet_data, backlog);
4066 /* Check if we have pending ipi, its better to send them now,
4067 * not waiting net_rx_action() end.
4069 if (sd->rps_ipi_list) {
4070 local_irq_disable();
4071 net_rps_action_and_irq_enable(sd);
4074 napi->weight = weight_p;
4075 local_irq_disable();
4076 while (work < quota) {
4077 struct sk_buff *skb;
4080 while ((skb = __skb_dequeue(&sd->process_queue))) {
4082 __netif_receive_skb(skb);
4083 local_irq_disable();
4084 input_queue_head_incr(sd);
4085 if (++work >= quota) {
4092 qlen = skb_queue_len(&sd->input_pkt_queue);
4094 skb_queue_splice_tail_init(&sd->input_pkt_queue,
4095 &sd->process_queue);
4097 if (qlen < quota - work) {
4099 * Inline a custom version of __napi_complete().
4100 * only current cpu owns and manipulates this napi,
4101 * and NAPI_STATE_SCHED is the only possible flag set on backlog.
4102 * we can use a plain write instead of clear_bit(),
4103 * and we dont need an smp_mb() memory barrier.
4105 list_del(&napi->poll_list);
4108 quota = work + qlen;
4118 * __napi_schedule - schedule for receive
4119 * @n: entry to schedule
4121 * The entry's receive function will be scheduled to run
4123 void __napi_schedule(struct napi_struct *n)
4125 unsigned long flags;
4127 local_irq_save(flags);
4128 ____napi_schedule(&__get_cpu_var(softnet_data), n);
4129 local_irq_restore(flags);
4131 EXPORT_SYMBOL(__napi_schedule);
4133 void __napi_complete(struct napi_struct *n)
4135 BUG_ON(!test_bit(NAPI_STATE_SCHED, &n->state));
4136 BUG_ON(n->gro_list);
4138 list_del(&n->poll_list);
4139 smp_mb__before_clear_bit();
4140 clear_bit(NAPI_STATE_SCHED, &n->state);
4142 EXPORT_SYMBOL(__napi_complete);
4144 void napi_complete(struct napi_struct *n)
4146 unsigned long flags;
4149 * don't let napi dequeue from the cpu poll list
4150 * just in case its running on a different cpu
4152 if (unlikely(test_bit(NAPI_STATE_NPSVC, &n->state)))
4155 napi_gro_flush(n, false);
4156 local_irq_save(flags);
4158 local_irq_restore(flags);
4160 EXPORT_SYMBOL(napi_complete);
4162 /* must be called under rcu_read_lock(), as we dont take a reference */
4163 struct napi_struct *napi_by_id(unsigned int napi_id)
4165 unsigned int hash = napi_id % HASH_SIZE(napi_hash);
4166 struct napi_struct *napi;
4168 hlist_for_each_entry_rcu(napi, &napi_hash[hash], napi_hash_node)
4169 if (napi->napi_id == napi_id)
4174 EXPORT_SYMBOL_GPL(napi_by_id);
4176 void napi_hash_add(struct napi_struct *napi)
4178 if (!test_and_set_bit(NAPI_STATE_HASHED, &napi->state)) {
4180 spin_lock(&napi_hash_lock);
4182 /* 0 is not a valid id, we also skip an id that is taken
4183 * we expect both events to be extremely rare
4186 while (!napi->napi_id) {
4187 napi->napi_id = ++napi_gen_id;
4188 if (napi_by_id(napi->napi_id))
4192 hlist_add_head_rcu(&napi->napi_hash_node,
4193 &napi_hash[napi->napi_id % HASH_SIZE(napi_hash)]);
4195 spin_unlock(&napi_hash_lock);
4198 EXPORT_SYMBOL_GPL(napi_hash_add);
4200 /* Warning : caller is responsible to make sure rcu grace period
4201 * is respected before freeing memory containing @napi
4203 void napi_hash_del(struct napi_struct *napi)
4205 spin_lock(&napi_hash_lock);
4207 if (test_and_clear_bit(NAPI_STATE_HASHED, &napi->state))
4208 hlist_del_rcu(&napi->napi_hash_node);
4210 spin_unlock(&napi_hash_lock);
4212 EXPORT_SYMBOL_GPL(napi_hash_del);
4214 void netif_napi_add(struct net_device *dev, struct napi_struct *napi,
4215 int (*poll)(struct napi_struct *, int), int weight)
4217 INIT_LIST_HEAD(&napi->poll_list);
4218 napi->gro_count = 0;
4219 napi->gro_list = NULL;
4222 if (weight > NAPI_POLL_WEIGHT)
4223 pr_err_once("netif_napi_add() called with weight %d on device %s\n",
4225 napi->weight = weight;
4226 list_add(&napi->dev_list, &dev->napi_list);
4228 #ifdef CONFIG_NETPOLL
4229 spin_lock_init(&napi->poll_lock);
4230 napi->poll_owner = -1;
4232 set_bit(NAPI_STATE_SCHED, &napi->state);
4234 EXPORT_SYMBOL(netif_napi_add);
4236 void netif_napi_del(struct napi_struct *napi)
4238 list_del_init(&napi->dev_list);
4239 napi_free_frags(napi);
4241 kfree_skb_list(napi->gro_list);
4242 napi->gro_list = NULL;
4243 napi->gro_count = 0;
4245 EXPORT_SYMBOL(netif_napi_del);
4247 static void net_rx_action(struct softirq_action *h)
4249 struct softnet_data *sd = &__get_cpu_var(softnet_data);
4250 unsigned long time_limit = jiffies + 2;
4251 int budget = netdev_budget;
4254 local_irq_disable();
4256 while (!list_empty(&sd->poll_list)) {
4257 struct napi_struct *n;
4260 /* If softirq window is exhuasted then punt.
4261 * Allow this to run for 2 jiffies since which will allow
4262 * an average latency of 1.5/HZ.
4264 if (unlikely(budget <= 0 || time_after_eq(jiffies, time_limit)))
4269 /* Even though interrupts have been re-enabled, this
4270 * access is safe because interrupts can only add new
4271 * entries to the tail of this list, and only ->poll()
4272 * calls can remove this head entry from the list.
4274 n = list_first_entry(&sd->poll_list, struct napi_struct, poll_list);
4276 have = netpoll_poll_lock(n);
4280 /* This NAPI_STATE_SCHED test is for avoiding a race
4281 * with netpoll's poll_napi(). Only the entity which
4282 * obtains the lock and sees NAPI_STATE_SCHED set will
4283 * actually make the ->poll() call. Therefore we avoid
4284 * accidentally calling ->poll() when NAPI is not scheduled.
4287 if (test_bit(NAPI_STATE_SCHED, &n->state)) {
4288 work = n->poll(n, weight);
4292 WARN_ON_ONCE(work > weight);
4296 local_irq_disable();
4298 /* Drivers must not modify the NAPI state if they
4299 * consume the entire weight. In such cases this code
4300 * still "owns" the NAPI instance and therefore can
4301 * move the instance around on the list at-will.
4303 if (unlikely(work == weight)) {
4304 if (unlikely(napi_disable_pending(n))) {
4307 local_irq_disable();
4310 /* flush too old packets
4311 * If HZ < 1000, flush all packets.
4314 napi_gro_flush(n, HZ >= 1000);
4315 local_irq_disable();
4317 list_move_tail(&n->poll_list, &sd->poll_list);
4321 netpoll_poll_unlock(have);
4324 net_rps_action_and_irq_enable(sd);
4326 #ifdef CONFIG_NET_DMA
4328 * There may not be any more sk_buffs coming right now, so push
4329 * any pending DMA copies to hardware
4331 dma_issue_pending_all();
4338 __raise_softirq_irqoff(NET_RX_SOFTIRQ);
4342 struct netdev_adjacent {
4343 struct net_device *dev;
4345 /* upper master flag, there can only be one master device per list */
4348 /* counter for the number of times this device was added to us */
4351 /* private field for the users */
4354 struct list_head list;
4355 struct rcu_head rcu;
4358 static struct netdev_adjacent *__netdev_find_adj_rcu(struct net_device *dev,
4359 struct net_device *adj_dev,
4360 struct list_head *adj_list)
4362 struct netdev_adjacent *adj;
4364 list_for_each_entry_rcu(adj, adj_list, list) {
4365 if (adj->dev == adj_dev)
4371 static struct netdev_adjacent *__netdev_find_adj(struct net_device *dev,
4372 struct net_device *adj_dev,
4373 struct list_head *adj_list)
4375 struct netdev_adjacent *adj;
4377 list_for_each_entry(adj, adj_list, list) {
4378 if (adj->dev == adj_dev)
4385 * netdev_has_upper_dev - Check if device is linked to an upper device
4387 * @upper_dev: upper device to check
4389 * Find out if a device is linked to specified upper device and return true
4390 * in case it is. Note that this checks only immediate upper device,
4391 * not through a complete stack of devices. The caller must hold the RTNL lock.
4393 bool netdev_has_upper_dev(struct net_device *dev,
4394 struct net_device *upper_dev)
4398 return __netdev_find_adj(dev, upper_dev, &dev->all_adj_list.upper);
4400 EXPORT_SYMBOL(netdev_has_upper_dev);
4403 * netdev_has_any_upper_dev - Check if device is linked to some device
4406 * Find out if a device is linked to an upper device and return true in case
4407 * it is. The caller must hold the RTNL lock.
4409 bool netdev_has_any_upper_dev(struct net_device *dev)
4413 return !list_empty(&dev->all_adj_list.upper);
4415 EXPORT_SYMBOL(netdev_has_any_upper_dev);
4418 * netdev_master_upper_dev_get - Get master upper device
4421 * Find a master upper device and return pointer to it or NULL in case
4422 * it's not there. The caller must hold the RTNL lock.
4424 struct net_device *netdev_master_upper_dev_get(struct net_device *dev)
4426 struct netdev_adjacent *upper;
4430 if (list_empty(&dev->adj_list.upper))
4433 upper = list_first_entry(&dev->adj_list.upper,
4434 struct netdev_adjacent, list);
4435 if (likely(upper->master))
4439 EXPORT_SYMBOL(netdev_master_upper_dev_get);
4441 void *netdev_adjacent_get_private(struct list_head *adj_list)
4443 struct netdev_adjacent *adj;
4445 adj = list_entry(adj_list, struct netdev_adjacent, list);
4447 return adj->private;
4449 EXPORT_SYMBOL(netdev_adjacent_get_private);
4452 * netdev_all_upper_get_next_dev_rcu - Get the next dev from upper list
4454 * @iter: list_head ** of the current position
4456 * Gets the next device from the dev's upper list, starting from iter
4457 * position. The caller must hold RCU read lock.
4459 struct net_device *netdev_all_upper_get_next_dev_rcu(struct net_device *dev,
4460 struct list_head **iter)
4462 struct netdev_adjacent *upper;
4464 WARN_ON_ONCE(!rcu_read_lock_held());
4466 upper = list_entry_rcu((*iter)->next, struct netdev_adjacent, list);
4468 if (&upper->list == &dev->all_adj_list.upper)
4471 *iter = &upper->list;
4475 EXPORT_SYMBOL(netdev_all_upper_get_next_dev_rcu);
4478 * netdev_lower_get_next_private - Get the next ->private from the
4479 * lower neighbour list
4481 * @iter: list_head ** of the current position
4483 * Gets the next netdev_adjacent->private from the dev's lower neighbour
4484 * list, starting from iter position. The caller must hold either hold the
4485 * RTNL lock or its own locking that guarantees that the neighbour lower
4486 * list will remain unchainged.
4488 void *netdev_lower_get_next_private(struct net_device *dev,
4489 struct list_head **iter)
4491 struct netdev_adjacent *lower;
4493 lower = list_entry(*iter, struct netdev_adjacent, list);
4495 if (&lower->list == &dev->adj_list.lower)
4499 *iter = lower->list.next;
4501 return lower->private;
4503 EXPORT_SYMBOL(netdev_lower_get_next_private);
4506 * netdev_lower_get_next_private_rcu - Get the next ->private from the
4507 * lower neighbour list, RCU
4510 * @iter: list_head ** of the current position
4512 * Gets the next netdev_adjacent->private from the dev's lower neighbour
4513 * list, starting from iter position. The caller must hold RCU read lock.
4515 void *netdev_lower_get_next_private_rcu(struct net_device *dev,
4516 struct list_head **iter)
4518 struct netdev_adjacent *lower;
4520 WARN_ON_ONCE(!rcu_read_lock_held());
4522 lower = list_entry_rcu((*iter)->next, struct netdev_adjacent, list);
4524 if (&lower->list == &dev->adj_list.lower)
4528 *iter = &lower->list;
4530 return lower->private;
4532 EXPORT_SYMBOL(netdev_lower_get_next_private_rcu);
4535 * netdev_lower_get_first_private_rcu - Get the first ->private from the
4536 * lower neighbour list, RCU
4540 * Gets the first netdev_adjacent->private from the dev's lower neighbour
4541 * list. The caller must hold RCU read lock.
4543 void *netdev_lower_get_first_private_rcu(struct net_device *dev)
4545 struct netdev_adjacent *lower;
4547 lower = list_first_or_null_rcu(&dev->adj_list.lower,
4548 struct netdev_adjacent, list);
4550 return lower->private;
4553 EXPORT_SYMBOL(netdev_lower_get_first_private_rcu);
4556 * netdev_master_upper_dev_get_rcu - Get master upper device
4559 * Find a master upper device and return pointer to it or NULL in case
4560 * it's not there. The caller must hold the RCU read lock.
4562 struct net_device *netdev_master_upper_dev_get_rcu(struct net_device *dev)
4564 struct netdev_adjacent *upper;
4566 upper = list_first_or_null_rcu(&dev->adj_list.upper,
4567 struct netdev_adjacent, list);
4568 if (upper && likely(upper->master))
4572 EXPORT_SYMBOL(netdev_master_upper_dev_get_rcu);
4574 static int __netdev_adjacent_dev_insert(struct net_device *dev,
4575 struct net_device *adj_dev,
4576 struct list_head *dev_list,
4577 void *private, bool master)
4579 struct netdev_adjacent *adj;
4580 char linkname[IFNAMSIZ+7];
4583 adj = __netdev_find_adj(dev, adj_dev, dev_list);
4590 adj = kmalloc(sizeof(*adj), GFP_KERNEL);
4595 adj->master = master;
4597 adj->private = private;
4600 pr_debug("dev_hold for %s, because of link added from %s to %s\n",
4601 adj_dev->name, dev->name, adj_dev->name);
4603 if (dev_list == &dev->adj_list.lower) {
4604 sprintf(linkname, "lower_%s", adj_dev->name);
4605 ret = sysfs_create_link(&(dev->dev.kobj),
4606 &(adj_dev->dev.kobj), linkname);
4609 } else if (dev_list == &dev->adj_list.upper) {
4610 sprintf(linkname, "upper_%s", adj_dev->name);
4611 ret = sysfs_create_link(&(dev->dev.kobj),
4612 &(adj_dev->dev.kobj), linkname);
4617 /* Ensure that master link is always the first item in list. */
4619 ret = sysfs_create_link(&(dev->dev.kobj),
4620 &(adj_dev->dev.kobj), "master");
4622 goto remove_symlinks;
4624 list_add_rcu(&adj->list, dev_list);
4626 list_add_tail_rcu(&adj->list, dev_list);
4632 if (dev_list == &dev->adj_list.lower) {
4633 sprintf(linkname, "lower_%s", adj_dev->name);
4634 sysfs_remove_link(&(dev->dev.kobj), linkname);
4635 } else if (dev_list == &dev->adj_list.upper) {
4636 sprintf(linkname, "upper_%s", adj_dev->name);
4637 sysfs_remove_link(&(dev->dev.kobj), linkname);
4647 void __netdev_adjacent_dev_remove(struct net_device *dev,
4648 struct net_device *adj_dev,
4649 struct list_head *dev_list)
4651 struct netdev_adjacent *adj;
4652 char linkname[IFNAMSIZ+7];
4654 adj = __netdev_find_adj(dev, adj_dev, dev_list);
4657 pr_err("tried to remove device %s from %s\n",
4658 dev->name, adj_dev->name);
4662 if (adj->ref_nr > 1) {
4663 pr_debug("%s to %s ref_nr-- = %d\n", dev->name, adj_dev->name,
4670 sysfs_remove_link(&(dev->dev.kobj), "master");
4672 if (dev_list == &dev->adj_list.lower) {
4673 sprintf(linkname, "lower_%s", adj_dev->name);
4674 sysfs_remove_link(&(dev->dev.kobj), linkname);
4675 } else if (dev_list == &dev->adj_list.upper) {
4676 sprintf(linkname, "upper_%s", adj_dev->name);
4677 sysfs_remove_link(&(dev->dev.kobj), linkname);
4680 list_del_rcu(&adj->list);
4681 pr_debug("dev_put for %s, because link removed from %s to %s\n",
4682 adj_dev->name, dev->name, adj_dev->name);
4684 kfree_rcu(adj, rcu);
4687 int __netdev_adjacent_dev_link_lists(struct net_device *dev,
4688 struct net_device *upper_dev,
4689 struct list_head *up_list,
4690 struct list_head *down_list,
4691 void *private, bool master)
4695 ret = __netdev_adjacent_dev_insert(dev, upper_dev, up_list, private,
4700 ret = __netdev_adjacent_dev_insert(upper_dev, dev, down_list, private,
4703 __netdev_adjacent_dev_remove(dev, upper_dev, up_list);
4710 int __netdev_adjacent_dev_link(struct net_device *dev,
4711 struct net_device *upper_dev)
4713 return __netdev_adjacent_dev_link_lists(dev, upper_dev,
4714 &dev->all_adj_list.upper,
4715 &upper_dev->all_adj_list.lower,
4719 void __netdev_adjacent_dev_unlink_lists(struct net_device *dev,
4720 struct net_device *upper_dev,
4721 struct list_head *up_list,
4722 struct list_head *down_list)
4724 __netdev_adjacent_dev_remove(dev, upper_dev, up_list);
4725 __netdev_adjacent_dev_remove(upper_dev, dev, down_list);
4728 void __netdev_adjacent_dev_unlink(struct net_device *dev,
4729 struct net_device *upper_dev)
4731 __netdev_adjacent_dev_unlink_lists(dev, upper_dev,
4732 &dev->all_adj_list.upper,
4733 &upper_dev->all_adj_list.lower);
4736 int __netdev_adjacent_dev_link_neighbour(struct net_device *dev,
4737 struct net_device *upper_dev,
4738 void *private, bool master)
4740 int ret = __netdev_adjacent_dev_link(dev, upper_dev);
4745 ret = __netdev_adjacent_dev_link_lists(dev, upper_dev,
4746 &dev->adj_list.upper,
4747 &upper_dev->adj_list.lower,
4750 __netdev_adjacent_dev_unlink(dev, upper_dev);
4757 void __netdev_adjacent_dev_unlink_neighbour(struct net_device *dev,
4758 struct net_device *upper_dev)
4760 __netdev_adjacent_dev_unlink(dev, upper_dev);
4761 __netdev_adjacent_dev_unlink_lists(dev, upper_dev,
4762 &dev->adj_list.upper,
4763 &upper_dev->adj_list.lower);
4766 static int __netdev_upper_dev_link(struct net_device *dev,
4767 struct net_device *upper_dev, bool master,
4770 struct netdev_adjacent *i, *j, *to_i, *to_j;
4775 if (dev == upper_dev)
4778 /* To prevent loops, check if dev is not upper device to upper_dev. */
4779 if (__netdev_find_adj(upper_dev, dev, &upper_dev->all_adj_list.upper))
4782 if (__netdev_find_adj(dev, upper_dev, &dev->all_adj_list.upper))
4785 if (master && netdev_master_upper_dev_get(dev))
4788 ret = __netdev_adjacent_dev_link_neighbour(dev, upper_dev, private,
4793 /* Now that we linked these devs, make all the upper_dev's
4794 * all_adj_list.upper visible to every dev's all_adj_list.lower an
4795 * versa, and don't forget the devices itself. All of these
4796 * links are non-neighbours.
4798 list_for_each_entry(i, &dev->all_adj_list.lower, list) {
4799 list_for_each_entry(j, &upper_dev->all_adj_list.upper, list) {
4800 pr_debug("Interlinking %s with %s, non-neighbour\n",
4801 i->dev->name, j->dev->name);
4802 ret = __netdev_adjacent_dev_link(i->dev, j->dev);
4808 /* add dev to every upper_dev's upper device */
4809 list_for_each_entry(i, &upper_dev->all_adj_list.upper, list) {
4810 pr_debug("linking %s's upper device %s with %s\n",
4811 upper_dev->name, i->dev->name, dev->name);
4812 ret = __netdev_adjacent_dev_link(dev, i->dev);
4814 goto rollback_upper_mesh;
4817 /* add upper_dev to every dev's lower device */
4818 list_for_each_entry(i, &dev->all_adj_list.lower, list) {
4819 pr_debug("linking %s's lower device %s with %s\n", dev->name,
4820 i->dev->name, upper_dev->name);
4821 ret = __netdev_adjacent_dev_link(i->dev, upper_dev);
4823 goto rollback_lower_mesh;
4826 call_netdevice_notifiers(NETDEV_CHANGEUPPER, dev);
4829 rollback_lower_mesh:
4831 list_for_each_entry(i, &dev->all_adj_list.lower, list) {
4834 __netdev_adjacent_dev_unlink(i->dev, upper_dev);
4839 rollback_upper_mesh:
4841 list_for_each_entry(i, &upper_dev->all_adj_list.upper, list) {
4844 __netdev_adjacent_dev_unlink(dev, i->dev);
4852 list_for_each_entry(i, &dev->all_adj_list.lower, list) {
4853 list_for_each_entry(j, &upper_dev->all_adj_list.upper, list) {
4854 if (i == to_i && j == to_j)
4856 __netdev_adjacent_dev_unlink(i->dev, j->dev);
4862 __netdev_adjacent_dev_unlink_neighbour(dev, upper_dev);
4868 * netdev_upper_dev_link - Add a link to the upper device
4870 * @upper_dev: new upper device
4872 * Adds a link to device which is upper to this one. The caller must hold
4873 * the RTNL lock. On a failure a negative errno code is returned.
4874 * On success the reference counts are adjusted and the function
4877 int netdev_upper_dev_link(struct net_device *dev,
4878 struct net_device *upper_dev)
4880 return __netdev_upper_dev_link(dev, upper_dev, false, NULL);
4882 EXPORT_SYMBOL(netdev_upper_dev_link);
4885 * netdev_master_upper_dev_link - Add a master link to the upper device
4887 * @upper_dev: new upper device
4889 * Adds a link to device which is upper to this one. In this case, only
4890 * one master upper device can be linked, although other non-master devices
4891 * might be linked as well. The caller must hold the RTNL lock.
4892 * On a failure a negative errno code is returned. On success the reference
4893 * counts are adjusted and the function returns zero.
4895 int netdev_master_upper_dev_link(struct net_device *dev,
4896 struct net_device *upper_dev)
4898 return __netdev_upper_dev_link(dev, upper_dev, true, NULL);
4900 EXPORT_SYMBOL(netdev_master_upper_dev_link);
4902 int netdev_master_upper_dev_link_private(struct net_device *dev,
4903 struct net_device *upper_dev,
4906 return __netdev_upper_dev_link(dev, upper_dev, true, private);
4908 EXPORT_SYMBOL(netdev_master_upper_dev_link_private);
4911 * netdev_upper_dev_unlink - Removes a link to upper device
4913 * @upper_dev: new upper device
4915 * Removes a link to device which is upper to this one. The caller must hold
4918 void netdev_upper_dev_unlink(struct net_device *dev,
4919 struct net_device *upper_dev)
4921 struct netdev_adjacent *i, *j;
4924 __netdev_adjacent_dev_unlink_neighbour(dev, upper_dev);
4926 /* Here is the tricky part. We must remove all dev's lower
4927 * devices from all upper_dev's upper devices and vice
4928 * versa, to maintain the graph relationship.
4930 list_for_each_entry(i, &dev->all_adj_list.lower, list)
4931 list_for_each_entry(j, &upper_dev->all_adj_list.upper, list)
4932 __netdev_adjacent_dev_unlink(i->dev, j->dev);
4934 /* remove also the devices itself from lower/upper device
4937 list_for_each_entry(i, &dev->all_adj_list.lower, list)
4938 __netdev_adjacent_dev_unlink(i->dev, upper_dev);
4940 list_for_each_entry(i, &upper_dev->all_adj_list.upper, list)
4941 __netdev_adjacent_dev_unlink(dev, i->dev);
4943 call_netdevice_notifiers(NETDEV_CHANGEUPPER, dev);
4945 EXPORT_SYMBOL(netdev_upper_dev_unlink);
4947 void *netdev_lower_dev_get_private_rcu(struct net_device *dev,
4948 struct net_device *lower_dev)
4950 struct netdev_adjacent *lower;
4954 lower = __netdev_find_adj_rcu(dev, lower_dev, &dev->adj_list.lower);
4958 return lower->private;
4960 EXPORT_SYMBOL(netdev_lower_dev_get_private_rcu);
4962 void *netdev_lower_dev_get_private(struct net_device *dev,
4963 struct net_device *lower_dev)
4965 struct netdev_adjacent *lower;
4969 lower = __netdev_find_adj(dev, lower_dev, &dev->adj_list.lower);
4973 return lower->private;
4975 EXPORT_SYMBOL(netdev_lower_dev_get_private);
4977 static void dev_change_rx_flags(struct net_device *dev, int flags)
4979 const struct net_device_ops *ops = dev->netdev_ops;
4981 if (ops->ndo_change_rx_flags)
4982 ops->ndo_change_rx_flags(dev, flags);
4985 static int __dev_set_promiscuity(struct net_device *dev, int inc, bool notify)
4987 unsigned int old_flags = dev->flags;
4993 dev->flags |= IFF_PROMISC;
4994 dev->promiscuity += inc;
4995 if (dev->promiscuity == 0) {
4998 * If inc causes overflow, untouch promisc and return error.
5001 dev->flags &= ~IFF_PROMISC;
5003 dev->promiscuity -= inc;
5004 pr_warn("%s: promiscuity touches roof, set promiscuity failed. promiscuity feature of device might be broken.\n",
5009 if (dev->flags != old_flags) {
5010 pr_info("device %s %s promiscuous mode\n",
5012 dev->flags & IFF_PROMISC ? "entered" : "left");
5013 if (audit_enabled) {
5014 current_uid_gid(&uid, &gid);
5015 audit_log(current->audit_context, GFP_ATOMIC,
5016 AUDIT_ANOM_PROMISCUOUS,
5017 "dev=%s prom=%d old_prom=%d auid=%u uid=%u gid=%u ses=%u",
5018 dev->name, (dev->flags & IFF_PROMISC),
5019 (old_flags & IFF_PROMISC),
5020 from_kuid(&init_user_ns, audit_get_loginuid(current)),
5021 from_kuid(&init_user_ns, uid),
5022 from_kgid(&init_user_ns, gid),
5023 audit_get_sessionid(current));
5026 dev_change_rx_flags(dev, IFF_PROMISC);
5029 __dev_notify_flags(dev, old_flags, IFF_PROMISC);
5034 * dev_set_promiscuity - update promiscuity count on a device
5038 * Add or remove promiscuity from a device. While the count in the device
5039 * remains above zero the interface remains promiscuous. Once it hits zero
5040 * the device reverts back to normal filtering operation. A negative inc
5041 * value is used to drop promiscuity on the device.
5042 * Return 0 if successful or a negative errno code on error.
5044 int dev_set_promiscuity(struct net_device *dev, int inc)
5046 unsigned int old_flags = dev->flags;
5049 err = __dev_set_promiscuity(dev, inc, true);
5052 if (dev->flags != old_flags)
5053 dev_set_rx_mode(dev);
5056 EXPORT_SYMBOL(dev_set_promiscuity);
5058 static int __dev_set_allmulti(struct net_device *dev, int inc, bool notify)
5060 unsigned int old_flags = dev->flags, old_gflags = dev->gflags;
5064 dev->flags |= IFF_ALLMULTI;
5065 dev->allmulti += inc;
5066 if (dev->allmulti == 0) {
5069 * If inc causes overflow, untouch allmulti and return error.
5072 dev->flags &= ~IFF_ALLMULTI;
5074 dev->allmulti -= inc;
5075 pr_warn("%s: allmulti touches roof, set allmulti failed. allmulti feature of device might be broken.\n",
5080 if (dev->flags ^ old_flags) {
5081 dev_change_rx_flags(dev, IFF_ALLMULTI);
5082 dev_set_rx_mode(dev);
5084 __dev_notify_flags(dev, old_flags,
5085 dev->gflags ^ old_gflags);
5091 * dev_set_allmulti - update allmulti count on a device
5095 * Add or remove reception of all multicast frames to a device. While the
5096 * count in the device remains above zero the interface remains listening
5097 * to all interfaces. Once it hits zero the device reverts back to normal
5098 * filtering operation. A negative @inc value is used to drop the counter
5099 * when releasing a resource needing all multicasts.
5100 * Return 0 if successful or a negative errno code on error.
5103 int dev_set_allmulti(struct net_device *dev, int inc)
5105 return __dev_set_allmulti(dev, inc, true);
5107 EXPORT_SYMBOL(dev_set_allmulti);
5110 * Upload unicast and multicast address lists to device and
5111 * configure RX filtering. When the device doesn't support unicast
5112 * filtering it is put in promiscuous mode while unicast addresses
5115 void __dev_set_rx_mode(struct net_device *dev)
5117 const struct net_device_ops *ops = dev->netdev_ops;
5119 /* dev_open will call this function so the list will stay sane. */
5120 if (!(dev->flags&IFF_UP))
5123 if (!netif_device_present(dev))
5126 if (!(dev->priv_flags & IFF_UNICAST_FLT)) {
5127 /* Unicast addresses changes may only happen under the rtnl,
5128 * therefore calling __dev_set_promiscuity here is safe.
5130 if (!netdev_uc_empty(dev) && !dev->uc_promisc) {
5131 __dev_set_promiscuity(dev, 1, false);
5132 dev->uc_promisc = true;
5133 } else if (netdev_uc_empty(dev) && dev->uc_promisc) {
5134 __dev_set_promiscuity(dev, -1, false);
5135 dev->uc_promisc = false;
5139 if (ops->ndo_set_rx_mode)
5140 ops->ndo_set_rx_mode(dev);
5143 void dev_set_rx_mode(struct net_device *dev)
5145 netif_addr_lock_bh(dev);
5146 __dev_set_rx_mode(dev);
5147 netif_addr_unlock_bh(dev);
5151 * dev_get_flags - get flags reported to userspace
5154 * Get the combination of flag bits exported through APIs to userspace.
5156 unsigned int dev_get_flags(const struct net_device *dev)
5160 flags = (dev->flags & ~(IFF_PROMISC |
5165 (dev->gflags & (IFF_PROMISC |
5168 if (netif_running(dev)) {
5169 if (netif_oper_up(dev))
5170 flags |= IFF_RUNNING;
5171 if (netif_carrier_ok(dev))
5172 flags |= IFF_LOWER_UP;
5173 if (netif_dormant(dev))
5174 flags |= IFF_DORMANT;
5179 EXPORT_SYMBOL(dev_get_flags);
5181 int __dev_change_flags(struct net_device *dev, unsigned int flags)
5183 unsigned int old_flags = dev->flags;
5189 * Set the flags on our device.
5192 dev->flags = (flags & (IFF_DEBUG | IFF_NOTRAILERS | IFF_NOARP |
5193 IFF_DYNAMIC | IFF_MULTICAST | IFF_PORTSEL |
5195 (dev->flags & (IFF_UP | IFF_VOLATILE | IFF_PROMISC |
5199 * Load in the correct multicast list now the flags have changed.
5202 if ((old_flags ^ flags) & IFF_MULTICAST)
5203 dev_change_rx_flags(dev, IFF_MULTICAST);
5205 dev_set_rx_mode(dev);
5208 * Have we downed the interface. We handle IFF_UP ourselves
5209 * according to user attempts to set it, rather than blindly
5214 if ((old_flags ^ flags) & IFF_UP) { /* Bit is different ? */
5215 ret = ((old_flags & IFF_UP) ? __dev_close : __dev_open)(dev);
5218 dev_set_rx_mode(dev);
5221 if ((flags ^ dev->gflags) & IFF_PROMISC) {
5222 int inc = (flags & IFF_PROMISC) ? 1 : -1;
5223 unsigned int old_flags = dev->flags;
5225 dev->gflags ^= IFF_PROMISC;
5227 if (__dev_set_promiscuity(dev, inc, false) >= 0)
5228 if (dev->flags != old_flags)
5229 dev_set_rx_mode(dev);
5232 /* NOTE: order of synchronization of IFF_PROMISC and IFF_ALLMULTI
5233 is important. Some (broken) drivers set IFF_PROMISC, when
5234 IFF_ALLMULTI is requested not asking us and not reporting.
5236 if ((flags ^ dev->gflags) & IFF_ALLMULTI) {
5237 int inc = (flags & IFF_ALLMULTI) ? 1 : -1;
5239 dev->gflags ^= IFF_ALLMULTI;
5240 __dev_set_allmulti(dev, inc, false);
5246 void __dev_notify_flags(struct net_device *dev, unsigned int old_flags,
5247 unsigned int gchanges)
5249 unsigned int changes = dev->flags ^ old_flags;
5252 rtmsg_ifinfo(RTM_NEWLINK, dev, gchanges, GFP_ATOMIC);
5254 if (changes & IFF_UP) {
5255 if (dev->flags & IFF_UP)
5256 call_netdevice_notifiers(NETDEV_UP, dev);
5258 call_netdevice_notifiers(NETDEV_DOWN, dev);
5261 if (dev->flags & IFF_UP &&
5262 (changes & ~(IFF_UP | IFF_PROMISC | IFF_ALLMULTI | IFF_VOLATILE))) {
5263 struct netdev_notifier_change_info change_info;
5265 change_info.flags_changed = changes;
5266 call_netdevice_notifiers_info(NETDEV_CHANGE, dev,
5272 * dev_change_flags - change device settings
5274 * @flags: device state flags
5276 * Change settings on device based state flags. The flags are
5277 * in the userspace exported format.
5279 int dev_change_flags(struct net_device *dev, unsigned int flags)
5282 unsigned int changes, old_flags = dev->flags, old_gflags = dev->gflags;
5284 ret = __dev_change_flags(dev, flags);
5288 changes = (old_flags ^ dev->flags) | (old_gflags ^ dev->gflags);
5289 __dev_notify_flags(dev, old_flags, changes);
5292 EXPORT_SYMBOL(dev_change_flags);
5295 * dev_set_mtu - Change maximum transfer unit
5297 * @new_mtu: new transfer unit
5299 * Change the maximum transfer size of the network device.
5301 int dev_set_mtu(struct net_device *dev, int new_mtu)
5303 const struct net_device_ops *ops = dev->netdev_ops;
5306 if (new_mtu == dev->mtu)
5309 /* MTU must be positive. */
5313 if (!netif_device_present(dev))
5317 if (ops->ndo_change_mtu)
5318 err = ops->ndo_change_mtu(dev, new_mtu);
5323 call_netdevice_notifiers(NETDEV_CHANGEMTU, dev);
5326 EXPORT_SYMBOL(dev_set_mtu);
5329 * dev_set_group - Change group this device belongs to
5331 * @new_group: group this device should belong to
5333 void dev_set_group(struct net_device *dev, int new_group)
5335 dev->group = new_group;
5337 EXPORT_SYMBOL(dev_set_group);
5340 * dev_set_mac_address - Change Media Access Control Address
5344 * Change the hardware (MAC) address of the device
5346 int dev_set_mac_address(struct net_device *dev, struct sockaddr *sa)
5348 const struct net_device_ops *ops = dev->netdev_ops;
5351 if (!ops->ndo_set_mac_address)
5353 if (sa->sa_family != dev->type)
5355 if (!netif_device_present(dev))
5357 err = ops->ndo_set_mac_address(dev, sa);
5360 dev->addr_assign_type = NET_ADDR_SET;
5361 call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
5362 add_device_randomness(dev->dev_addr, dev->addr_len);
5365 EXPORT_SYMBOL(dev_set_mac_address);
5368 * dev_change_carrier - Change device carrier
5370 * @new_carrier: new value
5372 * Change device carrier
5374 int dev_change_carrier(struct net_device *dev, bool new_carrier)
5376 const struct net_device_ops *ops = dev->netdev_ops;
5378 if (!ops->ndo_change_carrier)
5380 if (!netif_device_present(dev))
5382 return ops->ndo_change_carrier(dev, new_carrier);
5384 EXPORT_SYMBOL(dev_change_carrier);
5387 * dev_get_phys_port_id - Get device physical port ID
5391 * Get device physical port ID
5393 int dev_get_phys_port_id(struct net_device *dev,
5394 struct netdev_phys_port_id *ppid)
5396 const struct net_device_ops *ops = dev->netdev_ops;
5398 if (!ops->ndo_get_phys_port_id)
5400 return ops->ndo_get_phys_port_id(dev, ppid);
5402 EXPORT_SYMBOL(dev_get_phys_port_id);
5405 * dev_new_index - allocate an ifindex
5406 * @net: the applicable net namespace
5408 * Returns a suitable unique value for a new device interface
5409 * number. The caller must hold the rtnl semaphore or the
5410 * dev_base_lock to be sure it remains unique.
5412 static int dev_new_index(struct net *net)
5414 int ifindex = net->ifindex;
5418 if (!__dev_get_by_index(net, ifindex))
5419 return net->ifindex = ifindex;
5423 /* Delayed registration/unregisteration */
5424 static LIST_HEAD(net_todo_list);
5425 static DECLARE_WAIT_QUEUE_HEAD(netdev_unregistering_wq);
5427 static void net_set_todo(struct net_device *dev)
5429 list_add_tail(&dev->todo_list, &net_todo_list);
5430 dev_net(dev)->dev_unreg_count++;
5433 static void rollback_registered_many(struct list_head *head)
5435 struct net_device *dev, *tmp;
5436 LIST_HEAD(close_head);
5438 BUG_ON(dev_boot_phase);
5441 list_for_each_entry_safe(dev, tmp, head, unreg_list) {
5442 /* Some devices call without registering
5443 * for initialization unwind. Remove those
5444 * devices and proceed with the remaining.
5446 if (dev->reg_state == NETREG_UNINITIALIZED) {
5447 pr_debug("unregister_netdevice: device %s/%p never was registered\n",
5451 list_del(&dev->unreg_list);
5454 dev->dismantle = true;
5455 BUG_ON(dev->reg_state != NETREG_REGISTERED);
5458 /* If device is running, close it first. */
5459 list_for_each_entry(dev, head, unreg_list)
5460 list_add_tail(&dev->close_list, &close_head);
5461 dev_close_many(&close_head);
5463 list_for_each_entry(dev, head, unreg_list) {
5464 /* And unlink it from device chain. */
5465 unlist_netdevice(dev);
5467 dev->reg_state = NETREG_UNREGISTERING;
5472 list_for_each_entry(dev, head, unreg_list) {
5473 /* Shutdown queueing discipline. */
5477 /* Notify protocols, that we are about to destroy
5478 this device. They should clean all the things.
5480 call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
5482 if (!dev->rtnl_link_ops ||
5483 dev->rtnl_link_state == RTNL_LINK_INITIALIZED)
5484 rtmsg_ifinfo(RTM_DELLINK, dev, ~0U, GFP_KERNEL);
5487 * Flush the unicast and multicast chains
5492 if (dev->netdev_ops->ndo_uninit)
5493 dev->netdev_ops->ndo_uninit(dev);
5495 /* Notifier chain MUST detach us all upper devices. */
5496 WARN_ON(netdev_has_any_upper_dev(dev));
5498 /* Remove entries from kobject tree */
5499 netdev_unregister_kobject(dev);
5501 /* Remove XPS queueing entries */
5502 netif_reset_xps_queues_gt(dev, 0);
5508 list_for_each_entry(dev, head, unreg_list)
5512 static void rollback_registered(struct net_device *dev)
5516 list_add(&dev->unreg_list, &single);
5517 rollback_registered_many(&single);
5521 static netdev_features_t netdev_fix_features(struct net_device *dev,
5522 netdev_features_t features)
5524 /* Fix illegal checksum combinations */
5525 if ((features & NETIF_F_HW_CSUM) &&
5526 (features & (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))) {
5527 netdev_warn(dev, "mixed HW and IP checksum settings.\n");
5528 features &= ~(NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM);
5531 /* TSO requires that SG is present as well. */
5532 if ((features & NETIF_F_ALL_TSO) && !(features & NETIF_F_SG)) {
5533 netdev_dbg(dev, "Dropping TSO features since no SG feature.\n");
5534 features &= ~NETIF_F_ALL_TSO;
5537 if ((features & NETIF_F_TSO) && !(features & NETIF_F_HW_CSUM) &&
5538 !(features & NETIF_F_IP_CSUM)) {
5539 netdev_dbg(dev, "Dropping TSO features since no CSUM feature.\n");
5540 features &= ~NETIF_F_TSO;
5541 features &= ~NETIF_F_TSO_ECN;
5544 if ((features & NETIF_F_TSO6) && !(features & NETIF_F_HW_CSUM) &&
5545 !(features & NETIF_F_IPV6_CSUM)) {
5546 netdev_dbg(dev, "Dropping TSO6 features since no CSUM feature.\n");
5547 features &= ~NETIF_F_TSO6;
5550 /* TSO ECN requires that TSO is present as well. */
5551 if ((features & NETIF_F_ALL_TSO) == NETIF_F_TSO_ECN)
5552 features &= ~NETIF_F_TSO_ECN;
5554 /* Software GSO depends on SG. */
5555 if ((features & NETIF_F_GSO) && !(features & NETIF_F_SG)) {
5556 netdev_dbg(dev, "Dropping NETIF_F_GSO since no SG feature.\n");
5557 features &= ~NETIF_F_GSO;
5560 /* UFO needs SG and checksumming */
5561 if (features & NETIF_F_UFO) {
5562 /* maybe split UFO into V4 and V6? */
5563 if (!((features & NETIF_F_GEN_CSUM) ||
5564 (features & (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))
5565 == (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))) {
5567 "Dropping NETIF_F_UFO since no checksum offload features.\n");
5568 features &= ~NETIF_F_UFO;
5571 if (!(features & NETIF_F_SG)) {
5573 "Dropping NETIF_F_UFO since no NETIF_F_SG feature.\n");
5574 features &= ~NETIF_F_UFO;
5581 int __netdev_update_features(struct net_device *dev)
5583 netdev_features_t features;
5588 features = netdev_get_wanted_features(dev);
5590 if (dev->netdev_ops->ndo_fix_features)
5591 features = dev->netdev_ops->ndo_fix_features(dev, features);
5593 /* driver might be less strict about feature dependencies */
5594 features = netdev_fix_features(dev, features);
5596 if (dev->features == features)
5599 netdev_dbg(dev, "Features changed: %pNF -> %pNF\n",
5600 &dev->features, &features);
5602 if (dev->netdev_ops->ndo_set_features)
5603 err = dev->netdev_ops->ndo_set_features(dev, features);
5605 if (unlikely(err < 0)) {
5607 "set_features() failed (%d); wanted %pNF, left %pNF\n",
5608 err, &features, &dev->features);
5613 dev->features = features;
5619 * netdev_update_features - recalculate device features
5620 * @dev: the device to check
5622 * Recalculate dev->features set and send notifications if it
5623 * has changed. Should be called after driver or hardware dependent
5624 * conditions might have changed that influence the features.
5626 void netdev_update_features(struct net_device *dev)
5628 if (__netdev_update_features(dev))
5629 netdev_features_change(dev);
5631 EXPORT_SYMBOL(netdev_update_features);
5634 * netdev_change_features - recalculate device features
5635 * @dev: the device to check
5637 * Recalculate dev->features set and send notifications even
5638 * if they have not changed. Should be called instead of
5639 * netdev_update_features() if also dev->vlan_features might
5640 * have changed to allow the changes to be propagated to stacked
5643 void netdev_change_features(struct net_device *dev)
5645 __netdev_update_features(dev);
5646 netdev_features_change(dev);
5648 EXPORT_SYMBOL(netdev_change_features);
5651 * netif_stacked_transfer_operstate - transfer operstate
5652 * @rootdev: the root or lower level device to transfer state from
5653 * @dev: the device to transfer operstate to
5655 * Transfer operational state from root to device. This is normally
5656 * called when a stacking relationship exists between the root
5657 * device and the device(a leaf device).
5659 void netif_stacked_transfer_operstate(const struct net_device *rootdev,
5660 struct net_device *dev)
5662 if (rootdev->operstate == IF_OPER_DORMANT)
5663 netif_dormant_on(dev);
5665 netif_dormant_off(dev);
5667 if (netif_carrier_ok(rootdev)) {
5668 if (!netif_carrier_ok(dev))
5669 netif_carrier_on(dev);
5671 if (netif_carrier_ok(dev))
5672 netif_carrier_off(dev);
5675 EXPORT_SYMBOL(netif_stacked_transfer_operstate);
5678 static int netif_alloc_rx_queues(struct net_device *dev)
5680 unsigned int i, count = dev->num_rx_queues;
5681 struct netdev_rx_queue *rx;
5685 rx = kcalloc(count, sizeof(struct netdev_rx_queue), GFP_KERNEL);
5691 for (i = 0; i < count; i++)
5697 static void netdev_init_one_queue(struct net_device *dev,
5698 struct netdev_queue *queue, void *_unused)
5700 /* Initialize queue lock */
5701 spin_lock_init(&queue->_xmit_lock);
5702 netdev_set_xmit_lockdep_class(&queue->_xmit_lock, dev->type);
5703 queue->xmit_lock_owner = -1;
5704 netdev_queue_numa_node_write(queue, NUMA_NO_NODE);
5707 dql_init(&queue->dql, HZ);
5711 static void netif_free_tx_queues(struct net_device *dev)
5713 if (is_vmalloc_addr(dev->_tx))
5719 static int netif_alloc_netdev_queues(struct net_device *dev)
5721 unsigned int count = dev->num_tx_queues;
5722 struct netdev_queue *tx;
5723 size_t sz = count * sizeof(*tx);
5725 BUG_ON(count < 1 || count > 0xffff);
5727 tx = kzalloc(sz, GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT);
5735 netdev_for_each_tx_queue(dev, netdev_init_one_queue, NULL);
5736 spin_lock_init(&dev->tx_global_lock);
5742 * register_netdevice - register a network device
5743 * @dev: device to register
5745 * Take a completed network device structure and add it to the kernel
5746 * interfaces. A %NETDEV_REGISTER message is sent to the netdev notifier
5747 * chain. 0 is returned on success. A negative errno code is returned
5748 * on a failure to set up the device, or if the name is a duplicate.
5750 * Callers must hold the rtnl semaphore. You may want
5751 * register_netdev() instead of this.
5754 * The locking appears insufficient to guarantee two parallel registers
5755 * will not get the same name.
5758 int register_netdevice(struct net_device *dev)
5761 struct net *net = dev_net(dev);
5763 BUG_ON(dev_boot_phase);
5768 /* When net_device's are persistent, this will be fatal. */
5769 BUG_ON(dev->reg_state != NETREG_UNINITIALIZED);
5772 spin_lock_init(&dev->addr_list_lock);
5773 netdev_set_addr_lockdep_class(dev);
5777 ret = dev_get_valid_name(net, dev, dev->name);
5781 /* Init, if this function is available */
5782 if (dev->netdev_ops->ndo_init) {
5783 ret = dev->netdev_ops->ndo_init(dev);
5791 if (((dev->hw_features | dev->features) &
5792 NETIF_F_HW_VLAN_CTAG_FILTER) &&
5793 (!dev->netdev_ops->ndo_vlan_rx_add_vid ||
5794 !dev->netdev_ops->ndo_vlan_rx_kill_vid)) {
5795 netdev_WARN(dev, "Buggy VLAN acceleration in driver!\n");
5802 dev->ifindex = dev_new_index(net);
5803 else if (__dev_get_by_index(net, dev->ifindex))
5806 if (dev->iflink == -1)
5807 dev->iflink = dev->ifindex;
5809 /* Transfer changeable features to wanted_features and enable
5810 * software offloads (GSO and GRO).
5812 dev->hw_features |= NETIF_F_SOFT_FEATURES;
5813 dev->features |= NETIF_F_SOFT_FEATURES;
5814 dev->wanted_features = dev->features & dev->hw_features;
5816 /* Turn on no cache copy if HW is doing checksum */
5817 if (!(dev->flags & IFF_LOOPBACK)) {
5818 dev->hw_features |= NETIF_F_NOCACHE_COPY;
5819 if (dev->features & NETIF_F_ALL_CSUM) {
5820 dev->wanted_features |= NETIF_F_NOCACHE_COPY;
5821 dev->features |= NETIF_F_NOCACHE_COPY;
5825 /* Make NETIF_F_HIGHDMA inheritable to VLAN devices.
5827 dev->vlan_features |= NETIF_F_HIGHDMA;
5829 /* Make NETIF_F_SG inheritable to tunnel devices.
5831 dev->hw_enc_features |= NETIF_F_SG;
5833 /* Make NETIF_F_SG inheritable to MPLS.
5835 dev->mpls_features |= NETIF_F_SG;
5837 ret = call_netdevice_notifiers(NETDEV_POST_INIT, dev);
5838 ret = notifier_to_errno(ret);
5842 ret = netdev_register_kobject(dev);
5845 dev->reg_state = NETREG_REGISTERED;
5847 __netdev_update_features(dev);
5850 * Default initial state at registry is that the
5851 * device is present.
5854 set_bit(__LINK_STATE_PRESENT, &dev->state);
5856 linkwatch_init_dev(dev);
5858 dev_init_scheduler(dev);
5860 list_netdevice(dev);
5861 add_device_randomness(dev->dev_addr, dev->addr_len);
5863 /* If the device has permanent device address, driver should
5864 * set dev_addr and also addr_assign_type should be set to
5865 * NET_ADDR_PERM (default value).
5867 if (dev->addr_assign_type == NET_ADDR_PERM)
5868 memcpy(dev->perm_addr, dev->dev_addr, dev->addr_len);
5870 /* Notify protocols, that a new device appeared. */
5871 ret = call_netdevice_notifiers(NETDEV_REGISTER, dev);
5872 ret = notifier_to_errno(ret);
5874 rollback_registered(dev);
5875 dev->reg_state = NETREG_UNREGISTERED;
5878 * Prevent userspace races by waiting until the network
5879 * device is fully setup before sending notifications.
5881 if (!dev->rtnl_link_ops ||
5882 dev->rtnl_link_state == RTNL_LINK_INITIALIZED)
5883 rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U, GFP_KERNEL);
5889 if (dev->netdev_ops->ndo_uninit)
5890 dev->netdev_ops->ndo_uninit(dev);
5893 EXPORT_SYMBOL(register_netdevice);
5896 * init_dummy_netdev - init a dummy network device for NAPI
5897 * @dev: device to init
5899 * This takes a network device structure and initialize the minimum
5900 * amount of fields so it can be used to schedule NAPI polls without
5901 * registering a full blown interface. This is to be used by drivers
5902 * that need to tie several hardware interfaces to a single NAPI
5903 * poll scheduler due to HW limitations.
5905 int init_dummy_netdev(struct net_device *dev)
5907 /* Clear everything. Note we don't initialize spinlocks
5908 * are they aren't supposed to be taken by any of the
5909 * NAPI code and this dummy netdev is supposed to be
5910 * only ever used for NAPI polls
5912 memset(dev, 0, sizeof(struct net_device));
5914 /* make sure we BUG if trying to hit standard
5915 * register/unregister code path
5917 dev->reg_state = NETREG_DUMMY;
5919 /* NAPI wants this */
5920 INIT_LIST_HEAD(&dev->napi_list);
5922 /* a dummy interface is started by default */
5923 set_bit(__LINK_STATE_PRESENT, &dev->state);
5924 set_bit(__LINK_STATE_START, &dev->state);
5926 /* Note : We dont allocate pcpu_refcnt for dummy devices,
5927 * because users of this 'device' dont need to change
5933 EXPORT_SYMBOL_GPL(init_dummy_netdev);
5937 * register_netdev - register a network device
5938 * @dev: device to register
5940 * Take a completed network device structure and add it to the kernel
5941 * interfaces. A %NETDEV_REGISTER message is sent to the netdev notifier
5942 * chain. 0 is returned on success. A negative errno code is returned
5943 * on a failure to set up the device, or if the name is a duplicate.
5945 * This is a wrapper around register_netdevice that takes the rtnl semaphore
5946 * and expands the device name if you passed a format string to
5949 int register_netdev(struct net_device *dev)
5954 err = register_netdevice(dev);
5958 EXPORT_SYMBOL(register_netdev);
5960 int netdev_refcnt_read(const struct net_device *dev)
5964 for_each_possible_cpu(i)
5965 refcnt += *per_cpu_ptr(dev->pcpu_refcnt, i);
5968 EXPORT_SYMBOL(netdev_refcnt_read);
5971 * netdev_wait_allrefs - wait until all references are gone.
5972 * @dev: target net_device
5974 * This is called when unregistering network devices.
5976 * Any protocol or device that holds a reference should register
5977 * for netdevice notification, and cleanup and put back the
5978 * reference if they receive an UNREGISTER event.
5979 * We can get stuck here if buggy protocols don't correctly
5982 static void netdev_wait_allrefs(struct net_device *dev)
5984 unsigned long rebroadcast_time, warning_time;
5987 linkwatch_forget_dev(dev);
5989 rebroadcast_time = warning_time = jiffies;
5990 refcnt = netdev_refcnt_read(dev);
5992 while (refcnt != 0) {
5993 if (time_after(jiffies, rebroadcast_time + 1 * HZ)) {
5996 /* Rebroadcast unregister notification */
5997 call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
6003 call_netdevice_notifiers(NETDEV_UNREGISTER_FINAL, dev);
6004 if (test_bit(__LINK_STATE_LINKWATCH_PENDING,
6006 /* We must not have linkwatch events
6007 * pending on unregister. If this
6008 * happens, we simply run the queue
6009 * unscheduled, resulting in a noop
6012 linkwatch_run_queue();
6017 rebroadcast_time = jiffies;
6022 refcnt = netdev_refcnt_read(dev);
6024 if (time_after(jiffies, warning_time + 10 * HZ)) {
6025 pr_emerg("unregister_netdevice: waiting for %s to become free. Usage count = %d\n",
6027 warning_time = jiffies;
6036 * register_netdevice(x1);
6037 * register_netdevice(x2);
6039 * unregister_netdevice(y1);
6040 * unregister_netdevice(y2);
6046 * We are invoked by rtnl_unlock().
6047 * This allows us to deal with problems:
6048 * 1) We can delete sysfs objects which invoke hotplug
6049 * without deadlocking with linkwatch via keventd.
6050 * 2) Since we run with the RTNL semaphore not held, we can sleep
6051 * safely in order to wait for the netdev refcnt to drop to zero.
6053 * We must not return until all unregister events added during
6054 * the interval the lock was held have been completed.
6056 void netdev_run_todo(void)
6058 struct list_head list;
6060 /* Snapshot list, allow later requests */
6061 list_replace_init(&net_todo_list, &list);
6066 /* Wait for rcu callbacks to finish before next phase */
6067 if (!list_empty(&list))
6070 while (!list_empty(&list)) {
6071 struct net_device *dev
6072 = list_first_entry(&list, struct net_device, todo_list);
6073 list_del(&dev->todo_list);
6076 call_netdevice_notifiers(NETDEV_UNREGISTER_FINAL, dev);
6079 if (unlikely(dev->reg_state != NETREG_UNREGISTERING)) {
6080 pr_err("network todo '%s' but state %d\n",
6081 dev->name, dev->reg_state);
6086 dev->reg_state = NETREG_UNREGISTERED;
6088 on_each_cpu(flush_backlog, dev, 1);
6090 netdev_wait_allrefs(dev);
6093 BUG_ON(netdev_refcnt_read(dev));
6094 WARN_ON(rcu_access_pointer(dev->ip_ptr));
6095 WARN_ON(rcu_access_pointer(dev->ip6_ptr));
6096 WARN_ON(dev->dn_ptr);
6098 if (dev->destructor)
6099 dev->destructor(dev);
6101 /* Report a network device has been unregistered */
6103 dev_net(dev)->dev_unreg_count--;
6105 wake_up(&netdev_unregistering_wq);
6107 /* Free network device */
6108 kobject_put(&dev->dev.kobj);
6112 /* Convert net_device_stats to rtnl_link_stats64. They have the same
6113 * fields in the same order, with only the type differing.
6115 void netdev_stats_to_stats64(struct rtnl_link_stats64 *stats64,
6116 const struct net_device_stats *netdev_stats)
6118 #if BITS_PER_LONG == 64
6119 BUILD_BUG_ON(sizeof(*stats64) != sizeof(*netdev_stats));
6120 memcpy(stats64, netdev_stats, sizeof(*stats64));
6122 size_t i, n = sizeof(*stats64) / sizeof(u64);
6123 const unsigned long *src = (const unsigned long *)netdev_stats;
6124 u64 *dst = (u64 *)stats64;
6126 BUILD_BUG_ON(sizeof(*netdev_stats) / sizeof(unsigned long) !=
6127 sizeof(*stats64) / sizeof(u64));
6128 for (i = 0; i < n; i++)
6132 EXPORT_SYMBOL(netdev_stats_to_stats64);
6135 * dev_get_stats - get network device statistics
6136 * @dev: device to get statistics from
6137 * @storage: place to store stats
6139 * Get network statistics from device. Return @storage.
6140 * The device driver may provide its own method by setting
6141 * dev->netdev_ops->get_stats64 or dev->netdev_ops->get_stats;
6142 * otherwise the internal statistics structure is used.
6144 struct rtnl_link_stats64 *dev_get_stats(struct net_device *dev,
6145 struct rtnl_link_stats64 *storage)
6147 const struct net_device_ops *ops = dev->netdev_ops;
6149 if (ops->ndo_get_stats64) {
6150 memset(storage, 0, sizeof(*storage));
6151 ops->ndo_get_stats64(dev, storage);
6152 } else if (ops->ndo_get_stats) {
6153 netdev_stats_to_stats64(storage, ops->ndo_get_stats(dev));
6155 netdev_stats_to_stats64(storage, &dev->stats);
6157 storage->rx_dropped += atomic_long_read(&dev->rx_dropped);
6160 EXPORT_SYMBOL(dev_get_stats);
6162 struct netdev_queue *dev_ingress_queue_create(struct net_device *dev)
6164 struct netdev_queue *queue = dev_ingress_queue(dev);
6166 #ifdef CONFIG_NET_CLS_ACT
6169 queue = kzalloc(sizeof(*queue), GFP_KERNEL);
6172 netdev_init_one_queue(dev, queue, NULL);
6173 queue->qdisc = &noop_qdisc;
6174 queue->qdisc_sleeping = &noop_qdisc;
6175 rcu_assign_pointer(dev->ingress_queue, queue);
6180 static const struct ethtool_ops default_ethtool_ops;
6182 void netdev_set_default_ethtool_ops(struct net_device *dev,
6183 const struct ethtool_ops *ops)
6185 if (dev->ethtool_ops == &default_ethtool_ops)
6186 dev->ethtool_ops = ops;
6188 EXPORT_SYMBOL_GPL(netdev_set_default_ethtool_ops);
6190 void netdev_freemem(struct net_device *dev)
6192 char *addr = (char *)dev - dev->padded;
6194 if (is_vmalloc_addr(addr))
6201 * alloc_netdev_mqs - allocate network device
6202 * @sizeof_priv: size of private data to allocate space for
6203 * @name: device name format string
6204 * @setup: callback to initialize device
6205 * @txqs: the number of TX subqueues to allocate
6206 * @rxqs: the number of RX subqueues to allocate
6208 * Allocates a struct net_device with private data area for driver use
6209 * and performs basic initialization. Also allocates subquue structs
6210 * for each queue on the device.
6212 struct net_device *alloc_netdev_mqs(int sizeof_priv, const char *name,
6213 void (*setup)(struct net_device *),
6214 unsigned int txqs, unsigned int rxqs)
6216 struct net_device *dev;
6218 struct net_device *p;
6220 BUG_ON(strlen(name) >= sizeof(dev->name));
6223 pr_err("alloc_netdev: Unable to allocate device with zero queues\n");
6229 pr_err("alloc_netdev: Unable to allocate device with zero RX queues\n");
6234 alloc_size = sizeof(struct net_device);
6236 /* ensure 32-byte alignment of private area */
6237 alloc_size = ALIGN(alloc_size, NETDEV_ALIGN);
6238 alloc_size += sizeof_priv;
6240 /* ensure 32-byte alignment of whole construct */
6241 alloc_size += NETDEV_ALIGN - 1;
6243 p = kzalloc(alloc_size, GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT);
6245 p = vzalloc(alloc_size);
6249 dev = PTR_ALIGN(p, NETDEV_ALIGN);
6250 dev->padded = (char *)dev - (char *)p;
6252 dev->pcpu_refcnt = alloc_percpu(int);
6253 if (!dev->pcpu_refcnt)
6256 if (dev_addr_init(dev))
6262 dev_net_set(dev, &init_net);
6264 dev->gso_max_size = GSO_MAX_SIZE;
6265 dev->gso_max_segs = GSO_MAX_SEGS;
6267 INIT_LIST_HEAD(&dev->napi_list);
6268 INIT_LIST_HEAD(&dev->unreg_list);
6269 INIT_LIST_HEAD(&dev->close_list);
6270 INIT_LIST_HEAD(&dev->link_watch_list);
6271 INIT_LIST_HEAD(&dev->adj_list.upper);
6272 INIT_LIST_HEAD(&dev->adj_list.lower);
6273 INIT_LIST_HEAD(&dev->all_adj_list.upper);
6274 INIT_LIST_HEAD(&dev->all_adj_list.lower);
6275 dev->priv_flags = IFF_XMIT_DST_RELEASE;
6278 dev->num_tx_queues = txqs;
6279 dev->real_num_tx_queues = txqs;
6280 if (netif_alloc_netdev_queues(dev))
6284 dev->num_rx_queues = rxqs;
6285 dev->real_num_rx_queues = rxqs;
6286 if (netif_alloc_rx_queues(dev))
6290 strcpy(dev->name, name);
6291 dev->group = INIT_NETDEV_GROUP;
6292 if (!dev->ethtool_ops)
6293 dev->ethtool_ops = &default_ethtool_ops;
6301 free_percpu(dev->pcpu_refcnt);
6302 netif_free_tx_queues(dev);
6308 netdev_freemem(dev);
6311 EXPORT_SYMBOL(alloc_netdev_mqs);
6314 * free_netdev - free network device
6317 * This function does the last stage of destroying an allocated device
6318 * interface. The reference to the device object is released.
6319 * If this is the last reference then it will be freed.
6321 void free_netdev(struct net_device *dev)
6323 struct napi_struct *p, *n;
6325 release_net(dev_net(dev));
6327 netif_free_tx_queues(dev);
6332 kfree(rcu_dereference_protected(dev->ingress_queue, 1));
6334 /* Flush device addresses */
6335 dev_addr_flush(dev);
6337 list_for_each_entry_safe(p, n, &dev->napi_list, dev_list)
6340 free_percpu(dev->pcpu_refcnt);
6341 dev->pcpu_refcnt = NULL;
6343 /* Compatibility with error handling in drivers */
6344 if (dev->reg_state == NETREG_UNINITIALIZED) {
6345 netdev_freemem(dev);
6349 BUG_ON(dev->reg_state != NETREG_UNREGISTERED);
6350 dev->reg_state = NETREG_RELEASED;
6352 /* will free via device release */
6353 put_device(&dev->dev);
6355 EXPORT_SYMBOL(free_netdev);
6358 * synchronize_net - Synchronize with packet receive processing
6360 * Wait for packets currently being received to be done.
6361 * Does not block later packets from starting.
6363 void synchronize_net(void)
6366 if (rtnl_is_locked())
6367 synchronize_rcu_expedited();
6371 EXPORT_SYMBOL(synchronize_net);
6374 * unregister_netdevice_queue - remove device from the kernel
6378 * This function shuts down a device interface and removes it
6379 * from the kernel tables.
6380 * If head not NULL, device is queued to be unregistered later.
6382 * Callers must hold the rtnl semaphore. You may want
6383 * unregister_netdev() instead of this.
6386 void unregister_netdevice_queue(struct net_device *dev, struct list_head *head)
6391 list_move_tail(&dev->unreg_list, head);
6393 rollback_registered(dev);
6394 /* Finish processing unregister after unlock */
6398 EXPORT_SYMBOL(unregister_netdevice_queue);
6401 * unregister_netdevice_many - unregister many devices
6402 * @head: list of devices
6404 void unregister_netdevice_many(struct list_head *head)
6406 struct net_device *dev;
6408 if (!list_empty(head)) {
6409 rollback_registered_many(head);
6410 list_for_each_entry(dev, head, unreg_list)
6414 EXPORT_SYMBOL(unregister_netdevice_many);
6417 * unregister_netdev - remove device from the kernel
6420 * This function shuts down a device interface and removes it
6421 * from the kernel tables.
6423 * This is just a wrapper for unregister_netdevice that takes
6424 * the rtnl semaphore. In general you want to use this and not
6425 * unregister_netdevice.
6427 void unregister_netdev(struct net_device *dev)
6430 unregister_netdevice(dev);
6433 EXPORT_SYMBOL(unregister_netdev);
6436 * dev_change_net_namespace - move device to different nethost namespace
6438 * @net: network namespace
6439 * @pat: If not NULL name pattern to try if the current device name
6440 * is already taken in the destination network namespace.
6442 * This function shuts down a device interface and moves it
6443 * to a new network namespace. On success 0 is returned, on
6444 * a failure a netagive errno code is returned.
6446 * Callers must hold the rtnl semaphore.
6449 int dev_change_net_namespace(struct net_device *dev, struct net *net, const char *pat)
6455 /* Don't allow namespace local devices to be moved. */
6457 if (dev->features & NETIF_F_NETNS_LOCAL)
6460 /* Ensure the device has been registrered */
6461 if (dev->reg_state != NETREG_REGISTERED)
6464 /* Get out if there is nothing todo */
6466 if (net_eq(dev_net(dev), net))
6469 /* Pick the destination device name, and ensure
6470 * we can use it in the destination network namespace.
6473 if (__dev_get_by_name(net, dev->name)) {
6474 /* We get here if we can't use the current device name */
6477 if (dev_get_valid_name(net, dev, pat) < 0)
6482 * And now a mini version of register_netdevice unregister_netdevice.
6485 /* If device is running close it first. */
6488 /* And unlink it from device chain */
6490 unlist_netdevice(dev);
6494 /* Shutdown queueing discipline. */
6497 /* Notify protocols, that we are about to destroy
6498 this device. They should clean all the things.
6500 Note that dev->reg_state stays at NETREG_REGISTERED.
6501 This is wanted because this way 8021q and macvlan know
6502 the device is just moving and can keep their slaves up.
6504 call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
6506 call_netdevice_notifiers(NETDEV_UNREGISTER_FINAL, dev);
6507 rtmsg_ifinfo(RTM_DELLINK, dev, ~0U, GFP_KERNEL);
6510 * Flush the unicast and multicast chains
6515 /* Send a netdev-removed uevent to the old namespace */
6516 kobject_uevent(&dev->dev.kobj, KOBJ_REMOVE);
6518 /* Actually switch the network namespace */
6519 dev_net_set(dev, net);
6521 /* If there is an ifindex conflict assign a new one */
6522 if (__dev_get_by_index(net, dev->ifindex)) {
6523 int iflink = (dev->iflink == dev->ifindex);
6524 dev->ifindex = dev_new_index(net);
6526 dev->iflink = dev->ifindex;
6529 /* Send a netdev-add uevent to the new namespace */
6530 kobject_uevent(&dev->dev.kobj, KOBJ_ADD);
6532 /* Fixup kobjects */
6533 err = device_rename(&dev->dev, dev->name);
6536 /* Add the device back in the hashes */
6537 list_netdevice(dev);
6539 /* Notify protocols, that a new device appeared. */
6540 call_netdevice_notifiers(NETDEV_REGISTER, dev);
6543 * Prevent userspace races by waiting until the network
6544 * device is fully setup before sending notifications.
6546 rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U, GFP_KERNEL);
6553 EXPORT_SYMBOL_GPL(dev_change_net_namespace);
6555 static int dev_cpu_callback(struct notifier_block *nfb,
6556 unsigned long action,
6559 struct sk_buff **list_skb;
6560 struct sk_buff *skb;
6561 unsigned int cpu, oldcpu = (unsigned long)ocpu;
6562 struct softnet_data *sd, *oldsd;
6564 if (action != CPU_DEAD && action != CPU_DEAD_FROZEN)
6567 local_irq_disable();
6568 cpu = smp_processor_id();
6569 sd = &per_cpu(softnet_data, cpu);
6570 oldsd = &per_cpu(softnet_data, oldcpu);
6572 /* Find end of our completion_queue. */
6573 list_skb = &sd->completion_queue;
6575 list_skb = &(*list_skb)->next;
6576 /* Append completion queue from offline CPU. */
6577 *list_skb = oldsd->completion_queue;
6578 oldsd->completion_queue = NULL;
6580 /* Append output queue from offline CPU. */
6581 if (oldsd->output_queue) {
6582 *sd->output_queue_tailp = oldsd->output_queue;
6583 sd->output_queue_tailp = oldsd->output_queue_tailp;
6584 oldsd->output_queue = NULL;
6585 oldsd->output_queue_tailp = &oldsd->output_queue;
6587 /* Append NAPI poll list from offline CPU. */
6588 if (!list_empty(&oldsd->poll_list)) {
6589 list_splice_init(&oldsd->poll_list, &sd->poll_list);
6590 raise_softirq_irqoff(NET_RX_SOFTIRQ);
6593 raise_softirq_irqoff(NET_TX_SOFTIRQ);
6596 /* Process offline CPU's input_pkt_queue */
6597 while ((skb = __skb_dequeue(&oldsd->process_queue))) {
6599 input_queue_head_incr(oldsd);
6601 while ((skb = __skb_dequeue(&oldsd->input_pkt_queue))) {
6603 input_queue_head_incr(oldsd);
6611 * netdev_increment_features - increment feature set by one
6612 * @all: current feature set
6613 * @one: new feature set
6614 * @mask: mask feature set
6616 * Computes a new feature set after adding a device with feature set
6617 * @one to the master device with current feature set @all. Will not
6618 * enable anything that is off in @mask. Returns the new feature set.
6620 netdev_features_t netdev_increment_features(netdev_features_t all,
6621 netdev_features_t one, netdev_features_t mask)
6623 if (mask & NETIF_F_GEN_CSUM)
6624 mask |= NETIF_F_ALL_CSUM;
6625 mask |= NETIF_F_VLAN_CHALLENGED;
6627 all |= one & (NETIF_F_ONE_FOR_ALL|NETIF_F_ALL_CSUM) & mask;
6628 all &= one | ~NETIF_F_ALL_FOR_ALL;
6630 /* If one device supports hw checksumming, set for all. */
6631 if (all & NETIF_F_GEN_CSUM)
6632 all &= ~(NETIF_F_ALL_CSUM & ~NETIF_F_GEN_CSUM);
6636 EXPORT_SYMBOL(netdev_increment_features);
6638 static struct hlist_head * __net_init netdev_create_hash(void)
6641 struct hlist_head *hash;
6643 hash = kmalloc(sizeof(*hash) * NETDEV_HASHENTRIES, GFP_KERNEL);
6645 for (i = 0; i < NETDEV_HASHENTRIES; i++)
6646 INIT_HLIST_HEAD(&hash[i]);
6651 /* Initialize per network namespace state */
6652 static int __net_init netdev_init(struct net *net)
6654 if (net != &init_net)
6655 INIT_LIST_HEAD(&net->dev_base_head);
6657 net->dev_name_head = netdev_create_hash();
6658 if (net->dev_name_head == NULL)
6661 net->dev_index_head = netdev_create_hash();
6662 if (net->dev_index_head == NULL)
6668 kfree(net->dev_name_head);
6674 * netdev_drivername - network driver for the device
6675 * @dev: network device
6677 * Determine network driver for device.
6679 const char *netdev_drivername(const struct net_device *dev)
6681 const struct device_driver *driver;
6682 const struct device *parent;
6683 const char *empty = "";
6685 parent = dev->dev.parent;
6689 driver = parent->driver;
6690 if (driver && driver->name)
6691 return driver->name;
6695 static int __netdev_printk(const char *level, const struct net_device *dev,
6696 struct va_format *vaf)
6700 if (dev && dev->dev.parent) {
6701 r = dev_printk_emit(level[1] - '0',
6704 dev_driver_string(dev->dev.parent),
6705 dev_name(dev->dev.parent),
6706 netdev_name(dev), vaf);
6708 r = printk("%s%s: %pV", level, netdev_name(dev), vaf);
6710 r = printk("%s(NULL net_device): %pV", level, vaf);
6716 int netdev_printk(const char *level, const struct net_device *dev,
6717 const char *format, ...)
6719 struct va_format vaf;
6723 va_start(args, format);
6728 r = __netdev_printk(level, dev, &vaf);
6734 EXPORT_SYMBOL(netdev_printk);
6736 #define define_netdev_printk_level(func, level) \
6737 int func(const struct net_device *dev, const char *fmt, ...) \
6740 struct va_format vaf; \
6743 va_start(args, fmt); \
6748 r = __netdev_printk(level, dev, &vaf); \
6754 EXPORT_SYMBOL(func);
6756 define_netdev_printk_level(netdev_emerg, KERN_EMERG);
6757 define_netdev_printk_level(netdev_alert, KERN_ALERT);
6758 define_netdev_printk_level(netdev_crit, KERN_CRIT);
6759 define_netdev_printk_level(netdev_err, KERN_ERR);
6760 define_netdev_printk_level(netdev_warn, KERN_WARNING);
6761 define_netdev_printk_level(netdev_notice, KERN_NOTICE);
6762 define_netdev_printk_level(netdev_info, KERN_INFO);
6764 static void __net_exit netdev_exit(struct net *net)
6766 kfree(net->dev_name_head);
6767 kfree(net->dev_index_head);
6770 static struct pernet_operations __net_initdata netdev_net_ops = {
6771 .init = netdev_init,
6772 .exit = netdev_exit,
6775 static void __net_exit default_device_exit(struct net *net)
6777 struct net_device *dev, *aux;
6779 * Push all migratable network devices back to the
6780 * initial network namespace
6783 for_each_netdev_safe(net, dev, aux) {
6785 char fb_name[IFNAMSIZ];
6787 /* Ignore unmoveable devices (i.e. loopback) */
6788 if (dev->features & NETIF_F_NETNS_LOCAL)
6791 /* Leave virtual devices for the generic cleanup */
6792 if (dev->rtnl_link_ops)
6795 /* Push remaining network devices to init_net */
6796 snprintf(fb_name, IFNAMSIZ, "dev%d", dev->ifindex);
6797 err = dev_change_net_namespace(dev, &init_net, fb_name);
6799 pr_emerg("%s: failed to move %s to init_net: %d\n",
6800 __func__, dev->name, err);
6807 static void __net_exit rtnl_lock_unregistering(struct list_head *net_list)
6809 /* Return with the rtnl_lock held when there are no network
6810 * devices unregistering in any network namespace in net_list.
6817 prepare_to_wait(&netdev_unregistering_wq, &wait,
6818 TASK_UNINTERRUPTIBLE);
6819 unregistering = false;
6821 list_for_each_entry(net, net_list, exit_list) {
6822 if (net->dev_unreg_count > 0) {
6823 unregistering = true;
6832 finish_wait(&netdev_unregistering_wq, &wait);
6835 static void __net_exit default_device_exit_batch(struct list_head *net_list)
6837 /* At exit all network devices most be removed from a network
6838 * namespace. Do this in the reverse order of registration.
6839 * Do this across as many network namespaces as possible to
6840 * improve batching efficiency.
6842 struct net_device *dev;
6844 LIST_HEAD(dev_kill_list);
6846 /* To prevent network device cleanup code from dereferencing
6847 * loopback devices or network devices that have been freed
6848 * wait here for all pending unregistrations to complete,
6849 * before unregistring the loopback device and allowing the
6850 * network namespace be freed.
6852 * The netdev todo list containing all network devices
6853 * unregistrations that happen in default_device_exit_batch
6854 * will run in the rtnl_unlock() at the end of
6855 * default_device_exit_batch.
6857 rtnl_lock_unregistering(net_list);
6858 list_for_each_entry(net, net_list, exit_list) {
6859 for_each_netdev_reverse(net, dev) {
6860 if (dev->rtnl_link_ops)
6861 dev->rtnl_link_ops->dellink(dev, &dev_kill_list);
6863 unregister_netdevice_queue(dev, &dev_kill_list);
6866 unregister_netdevice_many(&dev_kill_list);
6867 list_del(&dev_kill_list);
6871 static struct pernet_operations __net_initdata default_device_ops = {
6872 .exit = default_device_exit,
6873 .exit_batch = default_device_exit_batch,
6877 * Initialize the DEV module. At boot time this walks the device list and
6878 * unhooks any devices that fail to initialise (normally hardware not
6879 * present) and leaves us with a valid list of present and active devices.
6884 * This is called single threaded during boot, so no need
6885 * to take the rtnl semaphore.
6887 static int __init net_dev_init(void)
6889 int i, rc = -ENOMEM;
6891 BUG_ON(!dev_boot_phase);
6893 if (dev_proc_init())
6896 if (netdev_kobject_init())
6899 INIT_LIST_HEAD(&ptype_all);
6900 for (i = 0; i < PTYPE_HASH_SIZE; i++)
6901 INIT_LIST_HEAD(&ptype_base[i]);
6903 INIT_LIST_HEAD(&offload_base);
6905 if (register_pernet_subsys(&netdev_net_ops))
6909 * Initialise the packet receive queues.
6912 for_each_possible_cpu(i) {
6913 struct softnet_data *sd = &per_cpu(softnet_data, i);
6915 memset(sd, 0, sizeof(*sd));
6916 skb_queue_head_init(&sd->input_pkt_queue);
6917 skb_queue_head_init(&sd->process_queue);
6918 sd->completion_queue = NULL;
6919 INIT_LIST_HEAD(&sd->poll_list);
6920 sd->output_queue = NULL;
6921 sd->output_queue_tailp = &sd->output_queue;
6923 sd->csd.func = rps_trigger_softirq;
6929 sd->backlog.poll = process_backlog;
6930 sd->backlog.weight = weight_p;
6931 sd->backlog.gro_list = NULL;
6932 sd->backlog.gro_count = 0;
6934 #ifdef CONFIG_NET_FLOW_LIMIT
6935 sd->flow_limit = NULL;
6941 /* The loopback device is special if any other network devices
6942 * is present in a network namespace the loopback device must
6943 * be present. Since we now dynamically allocate and free the
6944 * loopback device ensure this invariant is maintained by
6945 * keeping the loopback device as the first device on the
6946 * list of network devices. Ensuring the loopback devices
6947 * is the first device that appears and the last network device
6950 if (register_pernet_device(&loopback_net_ops))
6953 if (register_pernet_device(&default_device_ops))
6956 open_softirq(NET_TX_SOFTIRQ, net_tx_action);
6957 open_softirq(NET_RX_SOFTIRQ, net_rx_action);
6959 hotcpu_notifier(dev_cpu_callback, 0);
6966 subsys_initcall(net_dev_init);