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 static 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);
503 * dev_remove_offload - remove packet offload handler
504 * @po: packet offload declaration
506 * Remove a packet offload handler that was previously added to the kernel
507 * offload handlers by dev_add_offload(). The passed &offload_type is
508 * removed from the kernel lists and can be freed or reused once this
511 * This call sleeps to guarantee that no CPU is looking at the packet
514 void dev_remove_offload(struct packet_offload *po)
516 __dev_remove_offload(po);
520 EXPORT_SYMBOL(dev_remove_offload);
522 /******************************************************************************
524 Device Boot-time Settings Routines
526 *******************************************************************************/
528 /* Boot time configuration table */
529 static struct netdev_boot_setup dev_boot_setup[NETDEV_BOOT_SETUP_MAX];
532 * netdev_boot_setup_add - add new setup entry
533 * @name: name of the device
534 * @map: configured settings for the device
536 * Adds new setup entry to the dev_boot_setup list. The function
537 * returns 0 on error and 1 on success. This is a generic routine to
540 static int netdev_boot_setup_add(char *name, struct ifmap *map)
542 struct netdev_boot_setup *s;
546 for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++) {
547 if (s[i].name[0] == '\0' || s[i].name[0] == ' ') {
548 memset(s[i].name, 0, sizeof(s[i].name));
549 strlcpy(s[i].name, name, IFNAMSIZ);
550 memcpy(&s[i].map, map, sizeof(s[i].map));
555 return i >= NETDEV_BOOT_SETUP_MAX ? 0 : 1;
559 * netdev_boot_setup_check - check boot time settings
560 * @dev: the netdevice
562 * Check boot time settings for the device.
563 * The found settings are set for the device to be used
564 * later in the device probing.
565 * Returns 0 if no settings found, 1 if they are.
567 int netdev_boot_setup_check(struct net_device *dev)
569 struct netdev_boot_setup *s = dev_boot_setup;
572 for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++) {
573 if (s[i].name[0] != '\0' && s[i].name[0] != ' ' &&
574 !strcmp(dev->name, s[i].name)) {
575 dev->irq = s[i].map.irq;
576 dev->base_addr = s[i].map.base_addr;
577 dev->mem_start = s[i].map.mem_start;
578 dev->mem_end = s[i].map.mem_end;
584 EXPORT_SYMBOL(netdev_boot_setup_check);
588 * netdev_boot_base - get address from boot time settings
589 * @prefix: prefix for network device
590 * @unit: id for network device
592 * Check boot time settings for the base address of device.
593 * The found settings are set for the device to be used
594 * later in the device probing.
595 * Returns 0 if no settings found.
597 unsigned long netdev_boot_base(const char *prefix, int unit)
599 const struct netdev_boot_setup *s = dev_boot_setup;
603 sprintf(name, "%s%d", prefix, unit);
606 * If device already registered then return base of 1
607 * to indicate not to probe for this interface
609 if (__dev_get_by_name(&init_net, name))
612 for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++)
613 if (!strcmp(name, s[i].name))
614 return s[i].map.base_addr;
619 * Saves at boot time configured settings for any netdevice.
621 int __init netdev_boot_setup(char *str)
626 str = get_options(str, ARRAY_SIZE(ints), ints);
631 memset(&map, 0, sizeof(map));
635 map.base_addr = ints[2];
637 map.mem_start = ints[3];
639 map.mem_end = ints[4];
641 /* Add new entry to the list */
642 return netdev_boot_setup_add(str, &map);
645 __setup("netdev=", netdev_boot_setup);
647 /*******************************************************************************
649 Device Interface Subroutines
651 *******************************************************************************/
654 * __dev_get_by_name - find a device by its name
655 * @net: the applicable net namespace
656 * @name: name to find
658 * Find an interface by name. Must be called under RTNL semaphore
659 * or @dev_base_lock. If the name is found a pointer to the device
660 * is returned. If the name is not found then %NULL is returned. The
661 * reference counters are not incremented so the caller must be
662 * careful with locks.
665 struct net_device *__dev_get_by_name(struct net *net, const char *name)
667 struct net_device *dev;
668 struct hlist_head *head = dev_name_hash(net, name);
670 hlist_for_each_entry(dev, head, name_hlist)
671 if (!strncmp(dev->name, name, IFNAMSIZ))
676 EXPORT_SYMBOL(__dev_get_by_name);
679 * dev_get_by_name_rcu - find a device by its name
680 * @net: the applicable net namespace
681 * @name: name to find
683 * Find an interface by name.
684 * If the name is found a pointer to the device is returned.
685 * If the name is not found then %NULL is returned.
686 * The reference counters are not incremented so the caller must be
687 * careful with locks. The caller must hold RCU lock.
690 struct net_device *dev_get_by_name_rcu(struct net *net, const char *name)
692 struct net_device *dev;
693 struct hlist_head *head = dev_name_hash(net, name);
695 hlist_for_each_entry_rcu(dev, head, name_hlist)
696 if (!strncmp(dev->name, name, IFNAMSIZ))
701 EXPORT_SYMBOL(dev_get_by_name_rcu);
704 * dev_get_by_name - find a device by its name
705 * @net: the applicable net namespace
706 * @name: name to find
708 * Find an interface by name. This can be called from any
709 * context and does its own locking. The returned handle has
710 * the usage count incremented and the caller must use dev_put() to
711 * release it when it is no longer needed. %NULL is returned if no
712 * matching device is found.
715 struct net_device *dev_get_by_name(struct net *net, const char *name)
717 struct net_device *dev;
720 dev = dev_get_by_name_rcu(net, name);
726 EXPORT_SYMBOL(dev_get_by_name);
729 * __dev_get_by_index - find a device by its ifindex
730 * @net: the applicable net namespace
731 * @ifindex: index of device
733 * Search for an interface by index. Returns %NULL if the device
734 * is not found or a pointer to the device. The device has not
735 * had its reference counter increased so the caller must be careful
736 * about locking. The caller must hold either the RTNL semaphore
740 struct net_device *__dev_get_by_index(struct net *net, int ifindex)
742 struct net_device *dev;
743 struct hlist_head *head = dev_index_hash(net, ifindex);
745 hlist_for_each_entry(dev, head, index_hlist)
746 if (dev->ifindex == ifindex)
751 EXPORT_SYMBOL(__dev_get_by_index);
754 * dev_get_by_index_rcu - find a device by its ifindex
755 * @net: the applicable net namespace
756 * @ifindex: index of device
758 * Search for an interface by index. Returns %NULL if the device
759 * is not found or a pointer to the device. The device has not
760 * had its reference counter increased so the caller must be careful
761 * about locking. The caller must hold RCU lock.
764 struct net_device *dev_get_by_index_rcu(struct net *net, int ifindex)
766 struct net_device *dev;
767 struct hlist_head *head = dev_index_hash(net, ifindex);
769 hlist_for_each_entry_rcu(dev, head, index_hlist)
770 if (dev->ifindex == ifindex)
775 EXPORT_SYMBOL(dev_get_by_index_rcu);
779 * dev_get_by_index - find a device by its ifindex
780 * @net: the applicable net namespace
781 * @ifindex: index of device
783 * Search for an interface by index. Returns NULL if the device
784 * is not found or a pointer to the device. The device returned has
785 * had a reference added and the pointer is safe until the user calls
786 * dev_put to indicate they have finished with it.
789 struct net_device *dev_get_by_index(struct net *net, int ifindex)
791 struct net_device *dev;
794 dev = dev_get_by_index_rcu(net, ifindex);
800 EXPORT_SYMBOL(dev_get_by_index);
803 * netdev_get_name - get a netdevice name, knowing its ifindex.
804 * @net: network namespace
805 * @name: a pointer to the buffer where the name will be stored.
806 * @ifindex: the ifindex of the interface to get the name from.
808 * The use of raw_seqcount_begin() and cond_resched() before
809 * retrying is required as we want to give the writers a chance
810 * to complete when CONFIG_PREEMPT is not set.
812 int netdev_get_name(struct net *net, char *name, int ifindex)
814 struct net_device *dev;
818 seq = raw_seqcount_begin(&devnet_rename_seq);
820 dev = dev_get_by_index_rcu(net, ifindex);
826 strcpy(name, dev->name);
828 if (read_seqcount_retry(&devnet_rename_seq, seq)) {
837 * dev_getbyhwaddr_rcu - find a device by its hardware address
838 * @net: the applicable net namespace
839 * @type: media type of device
840 * @ha: hardware address
842 * Search for an interface by MAC address. Returns NULL if the device
843 * is not found or a pointer to the device.
844 * The caller must hold RCU or RTNL.
845 * The returned device has not had its ref count increased
846 * and the caller must therefore be careful about locking
850 struct net_device *dev_getbyhwaddr_rcu(struct net *net, unsigned short type,
853 struct net_device *dev;
855 for_each_netdev_rcu(net, dev)
856 if (dev->type == type &&
857 !memcmp(dev->dev_addr, ha, dev->addr_len))
862 EXPORT_SYMBOL(dev_getbyhwaddr_rcu);
864 struct net_device *__dev_getfirstbyhwtype(struct net *net, unsigned short type)
866 struct net_device *dev;
869 for_each_netdev(net, dev)
870 if (dev->type == type)
875 EXPORT_SYMBOL(__dev_getfirstbyhwtype);
877 struct net_device *dev_getfirstbyhwtype(struct net *net, unsigned short type)
879 struct net_device *dev, *ret = NULL;
882 for_each_netdev_rcu(net, dev)
883 if (dev->type == type) {
891 EXPORT_SYMBOL(dev_getfirstbyhwtype);
894 * dev_get_by_flags_rcu - find any device with given flags
895 * @net: the applicable net namespace
896 * @if_flags: IFF_* values
897 * @mask: bitmask of bits in if_flags to check
899 * Search for any interface with the given flags. Returns NULL if a device
900 * is not found or a pointer to the device. Must be called inside
901 * rcu_read_lock(), and result refcount is unchanged.
904 struct net_device *dev_get_by_flags_rcu(struct net *net, unsigned short if_flags,
907 struct net_device *dev, *ret;
910 for_each_netdev_rcu(net, dev) {
911 if (((dev->flags ^ if_flags) & mask) == 0) {
918 EXPORT_SYMBOL(dev_get_by_flags_rcu);
921 * dev_valid_name - check if name is okay for network device
924 * Network device names need to be valid file names to
925 * to allow sysfs to work. We also disallow any kind of
928 bool dev_valid_name(const char *name)
932 if (strlen(name) >= IFNAMSIZ)
934 if (!strcmp(name, ".") || !strcmp(name, ".."))
938 if (*name == '/' || isspace(*name))
944 EXPORT_SYMBOL(dev_valid_name);
947 * __dev_alloc_name - allocate a name for a device
948 * @net: network namespace to allocate the device name in
949 * @name: name format string
950 * @buf: scratch buffer and result name string
952 * Passed a format string - eg "lt%d" it will try and find a suitable
953 * id. It scans list of devices to build up a free map, then chooses
954 * the first empty slot. The caller must hold the dev_base or rtnl lock
955 * while allocating the name and adding the device in order to avoid
957 * Limited to bits_per_byte * page size devices (ie 32K on most platforms).
958 * Returns the number of the unit assigned or a negative errno code.
961 static int __dev_alloc_name(struct net *net, const char *name, char *buf)
965 const int max_netdevices = 8*PAGE_SIZE;
966 unsigned long *inuse;
967 struct net_device *d;
969 p = strnchr(name, IFNAMSIZ-1, '%');
972 * Verify the string as this thing may have come from
973 * the user. There must be either one "%d" and no other "%"
976 if (p[1] != 'd' || strchr(p + 2, '%'))
979 /* Use one page as a bit array of possible slots */
980 inuse = (unsigned long *) get_zeroed_page(GFP_ATOMIC);
984 for_each_netdev(net, d) {
985 if (!sscanf(d->name, name, &i))
987 if (i < 0 || i >= max_netdevices)
990 /* avoid cases where sscanf is not exact inverse of printf */
991 snprintf(buf, IFNAMSIZ, name, i);
992 if (!strncmp(buf, d->name, IFNAMSIZ))
996 i = find_first_zero_bit(inuse, max_netdevices);
997 free_page((unsigned long) inuse);
1001 snprintf(buf, IFNAMSIZ, name, i);
1002 if (!__dev_get_by_name(net, buf))
1005 /* It is possible to run out of possible slots
1006 * when the name is long and there isn't enough space left
1007 * for the digits, or if all bits are used.
1013 * dev_alloc_name - allocate a name for a device
1015 * @name: name format string
1017 * Passed a format string - eg "lt%d" it will try and find a suitable
1018 * id. It scans list of devices to build up a free map, then chooses
1019 * the first empty slot. The caller must hold the dev_base or rtnl lock
1020 * while allocating the name and adding the device in order to avoid
1022 * Limited to bits_per_byte * page size devices (ie 32K on most platforms).
1023 * Returns the number of the unit assigned or a negative errno code.
1026 int dev_alloc_name(struct net_device *dev, const char *name)
1032 BUG_ON(!dev_net(dev));
1034 ret = __dev_alloc_name(net, name, buf);
1036 strlcpy(dev->name, buf, IFNAMSIZ);
1039 EXPORT_SYMBOL(dev_alloc_name);
1041 static int dev_alloc_name_ns(struct net *net,
1042 struct net_device *dev,
1048 ret = __dev_alloc_name(net, name, buf);
1050 strlcpy(dev->name, buf, IFNAMSIZ);
1054 static int dev_get_valid_name(struct net *net,
1055 struct net_device *dev,
1060 if (!dev_valid_name(name))
1063 if (strchr(name, '%'))
1064 return dev_alloc_name_ns(net, dev, name);
1065 else if (__dev_get_by_name(net, name))
1067 else if (dev->name != name)
1068 strlcpy(dev->name, name, IFNAMSIZ);
1074 * dev_change_name - change name of a device
1076 * @newname: name (or format string) must be at least IFNAMSIZ
1078 * Change name of a device, can pass format strings "eth%d".
1081 int dev_change_name(struct net_device *dev, const char *newname)
1083 char oldname[IFNAMSIZ];
1089 BUG_ON(!dev_net(dev));
1092 if (dev->flags & IFF_UP)
1095 write_seqcount_begin(&devnet_rename_seq);
1097 if (strncmp(newname, dev->name, IFNAMSIZ) == 0) {
1098 write_seqcount_end(&devnet_rename_seq);
1102 memcpy(oldname, dev->name, IFNAMSIZ);
1104 err = dev_get_valid_name(net, dev, newname);
1106 write_seqcount_end(&devnet_rename_seq);
1111 ret = device_rename(&dev->dev, dev->name);
1113 memcpy(dev->name, oldname, IFNAMSIZ);
1114 write_seqcount_end(&devnet_rename_seq);
1118 write_seqcount_end(&devnet_rename_seq);
1120 write_lock_bh(&dev_base_lock);
1121 hlist_del_rcu(&dev->name_hlist);
1122 write_unlock_bh(&dev_base_lock);
1126 write_lock_bh(&dev_base_lock);
1127 hlist_add_head_rcu(&dev->name_hlist, dev_name_hash(net, dev->name));
1128 write_unlock_bh(&dev_base_lock);
1130 ret = call_netdevice_notifiers(NETDEV_CHANGENAME, dev);
1131 ret = notifier_to_errno(ret);
1134 /* err >= 0 after dev_alloc_name() or stores the first errno */
1137 write_seqcount_begin(&devnet_rename_seq);
1138 memcpy(dev->name, oldname, IFNAMSIZ);
1141 pr_err("%s: name change rollback failed: %d\n",
1150 * dev_set_alias - change ifalias of a device
1152 * @alias: name up to IFALIASZ
1153 * @len: limit of bytes to copy from info
1155 * Set ifalias for a device,
1157 int dev_set_alias(struct net_device *dev, const char *alias, size_t len)
1163 if (len >= IFALIASZ)
1167 kfree(dev->ifalias);
1168 dev->ifalias = NULL;
1172 new_ifalias = krealloc(dev->ifalias, len + 1, GFP_KERNEL);
1175 dev->ifalias = new_ifalias;
1177 strlcpy(dev->ifalias, alias, len+1);
1183 * netdev_features_change - device changes features
1184 * @dev: device to cause notification
1186 * Called to indicate a device has changed features.
1188 void netdev_features_change(struct net_device *dev)
1190 call_netdevice_notifiers(NETDEV_FEAT_CHANGE, dev);
1192 EXPORT_SYMBOL(netdev_features_change);
1195 * netdev_state_change - device changes state
1196 * @dev: device to cause notification
1198 * Called to indicate a device has changed state. This function calls
1199 * the notifier chains for netdev_chain and sends a NEWLINK message
1200 * to the routing socket.
1202 void netdev_state_change(struct net_device *dev)
1204 if (dev->flags & IFF_UP) {
1205 call_netdevice_notifiers(NETDEV_CHANGE, dev);
1206 rtmsg_ifinfo(RTM_NEWLINK, dev, 0, GFP_KERNEL);
1209 EXPORT_SYMBOL(netdev_state_change);
1212 * netdev_notify_peers - notify network peers about existence of @dev
1213 * @dev: network device
1215 * Generate traffic such that interested network peers are aware of
1216 * @dev, such as by generating a gratuitous ARP. This may be used when
1217 * a device wants to inform the rest of the network about some sort of
1218 * reconfiguration such as a failover event or virtual machine
1221 void netdev_notify_peers(struct net_device *dev)
1224 call_netdevice_notifiers(NETDEV_NOTIFY_PEERS, dev);
1227 EXPORT_SYMBOL(netdev_notify_peers);
1229 static int __dev_open(struct net_device *dev)
1231 const struct net_device_ops *ops = dev->netdev_ops;
1236 if (!netif_device_present(dev))
1239 /* Block netpoll from trying to do any rx path servicing.
1240 * If we don't do this there is a chance ndo_poll_controller
1241 * or ndo_poll may be running while we open the device
1243 netpoll_rx_disable(dev);
1245 ret = call_netdevice_notifiers(NETDEV_PRE_UP, dev);
1246 ret = notifier_to_errno(ret);
1250 set_bit(__LINK_STATE_START, &dev->state);
1252 if (ops->ndo_validate_addr)
1253 ret = ops->ndo_validate_addr(dev);
1255 if (!ret && ops->ndo_open)
1256 ret = ops->ndo_open(dev);
1258 netpoll_rx_enable(dev);
1261 clear_bit(__LINK_STATE_START, &dev->state);
1263 dev->flags |= IFF_UP;
1264 net_dmaengine_get();
1265 dev_set_rx_mode(dev);
1267 add_device_randomness(dev->dev_addr, dev->addr_len);
1274 * dev_open - prepare an interface for use.
1275 * @dev: device to open
1277 * Takes a device from down to up state. The device's private open
1278 * function is invoked and then the multicast lists are loaded. Finally
1279 * the device is moved into the up state and a %NETDEV_UP message is
1280 * sent to the netdev notifier chain.
1282 * Calling this function on an active interface is a nop. On a failure
1283 * a negative errno code is returned.
1285 int dev_open(struct net_device *dev)
1289 if (dev->flags & IFF_UP)
1292 ret = __dev_open(dev);
1296 rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP|IFF_RUNNING, GFP_KERNEL);
1297 call_netdevice_notifiers(NETDEV_UP, dev);
1301 EXPORT_SYMBOL(dev_open);
1303 static int __dev_close_many(struct list_head *head)
1305 struct net_device *dev;
1310 list_for_each_entry(dev, head, close_list) {
1311 call_netdevice_notifiers(NETDEV_GOING_DOWN, dev);
1313 clear_bit(__LINK_STATE_START, &dev->state);
1315 /* Synchronize to scheduled poll. We cannot touch poll list, it
1316 * can be even on different cpu. So just clear netif_running().
1318 * dev->stop() will invoke napi_disable() on all of it's
1319 * napi_struct instances on this device.
1321 smp_mb__after_clear_bit(); /* Commit netif_running(). */
1324 dev_deactivate_many(head);
1326 list_for_each_entry(dev, head, close_list) {
1327 const struct net_device_ops *ops = dev->netdev_ops;
1330 * Call the device specific close. This cannot fail.
1331 * Only if device is UP
1333 * We allow it to be called even after a DETACH hot-plug
1339 dev->flags &= ~IFF_UP;
1340 net_dmaengine_put();
1346 static int __dev_close(struct net_device *dev)
1351 /* Temporarily disable netpoll until the interface is down */
1352 netpoll_rx_disable(dev);
1354 list_add(&dev->close_list, &single);
1355 retval = __dev_close_many(&single);
1358 netpoll_rx_enable(dev);
1362 static int dev_close_many(struct list_head *head)
1364 struct net_device *dev, *tmp;
1366 /* Remove the devices that don't need to be closed */
1367 list_for_each_entry_safe(dev, tmp, head, close_list)
1368 if (!(dev->flags & IFF_UP))
1369 list_del_init(&dev->close_list);
1371 __dev_close_many(head);
1373 list_for_each_entry_safe(dev, tmp, head, close_list) {
1374 rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP|IFF_RUNNING, GFP_KERNEL);
1375 call_netdevice_notifiers(NETDEV_DOWN, dev);
1376 list_del_init(&dev->close_list);
1383 * dev_close - shutdown an interface.
1384 * @dev: device to shutdown
1386 * This function moves an active device into down state. A
1387 * %NETDEV_GOING_DOWN is sent to the netdev notifier chain. The device
1388 * is then deactivated and finally a %NETDEV_DOWN is sent to the notifier
1391 int dev_close(struct net_device *dev)
1393 if (dev->flags & IFF_UP) {
1396 /* Block netpoll rx while the interface is going down */
1397 netpoll_rx_disable(dev);
1399 list_add(&dev->close_list, &single);
1400 dev_close_many(&single);
1403 netpoll_rx_enable(dev);
1407 EXPORT_SYMBOL(dev_close);
1411 * dev_disable_lro - disable Large Receive Offload on a device
1414 * Disable Large Receive Offload (LRO) on a net device. Must be
1415 * called under RTNL. This is needed if received packets may be
1416 * forwarded to another interface.
1418 void dev_disable_lro(struct net_device *dev)
1421 * If we're trying to disable lro on a vlan device
1422 * use the underlying physical device instead
1424 if (is_vlan_dev(dev))
1425 dev = vlan_dev_real_dev(dev);
1427 /* the same for macvlan devices */
1428 if (netif_is_macvlan(dev))
1429 dev = macvlan_dev_real_dev(dev);
1431 dev->wanted_features &= ~NETIF_F_LRO;
1432 netdev_update_features(dev);
1434 if (unlikely(dev->features & NETIF_F_LRO))
1435 netdev_WARN(dev, "failed to disable LRO!\n");
1437 EXPORT_SYMBOL(dev_disable_lro);
1439 static int call_netdevice_notifier(struct notifier_block *nb, unsigned long val,
1440 struct net_device *dev)
1442 struct netdev_notifier_info info;
1444 netdev_notifier_info_init(&info, dev);
1445 return nb->notifier_call(nb, val, &info);
1448 static int dev_boot_phase = 1;
1451 * register_netdevice_notifier - register a network notifier block
1454 * Register a notifier to be called when network device events occur.
1455 * The notifier passed is linked into the kernel structures and must
1456 * not be reused until it has been unregistered. A negative errno code
1457 * is returned on a failure.
1459 * When registered all registration and up events are replayed
1460 * to the new notifier to allow device to have a race free
1461 * view of the network device list.
1464 int register_netdevice_notifier(struct notifier_block *nb)
1466 struct net_device *dev;
1467 struct net_device *last;
1472 err = raw_notifier_chain_register(&netdev_chain, nb);
1478 for_each_netdev(net, dev) {
1479 err = call_netdevice_notifier(nb, NETDEV_REGISTER, dev);
1480 err = notifier_to_errno(err);
1484 if (!(dev->flags & IFF_UP))
1487 call_netdevice_notifier(nb, NETDEV_UP, dev);
1498 for_each_netdev(net, dev) {
1502 if (dev->flags & IFF_UP) {
1503 call_netdevice_notifier(nb, NETDEV_GOING_DOWN,
1505 call_netdevice_notifier(nb, NETDEV_DOWN, dev);
1507 call_netdevice_notifier(nb, NETDEV_UNREGISTER, dev);
1512 raw_notifier_chain_unregister(&netdev_chain, nb);
1515 EXPORT_SYMBOL(register_netdevice_notifier);
1518 * unregister_netdevice_notifier - unregister a network notifier block
1521 * Unregister a notifier previously registered by
1522 * register_netdevice_notifier(). The notifier is unlinked into the
1523 * kernel structures and may then be reused. A negative errno code
1524 * is returned on a failure.
1526 * After unregistering unregister and down device events are synthesized
1527 * for all devices on the device list to the removed notifier to remove
1528 * the need for special case cleanup code.
1531 int unregister_netdevice_notifier(struct notifier_block *nb)
1533 struct net_device *dev;
1538 err = raw_notifier_chain_unregister(&netdev_chain, nb);
1543 for_each_netdev(net, dev) {
1544 if (dev->flags & IFF_UP) {
1545 call_netdevice_notifier(nb, NETDEV_GOING_DOWN,
1547 call_netdevice_notifier(nb, NETDEV_DOWN, dev);
1549 call_netdevice_notifier(nb, NETDEV_UNREGISTER, dev);
1556 EXPORT_SYMBOL(unregister_netdevice_notifier);
1559 * call_netdevice_notifiers_info - call all network notifier blocks
1560 * @val: value passed unmodified to notifier function
1561 * @dev: net_device pointer passed unmodified to notifier function
1562 * @info: notifier information data
1564 * Call all network notifier blocks. Parameters and return value
1565 * are as for raw_notifier_call_chain().
1568 static int call_netdevice_notifiers_info(unsigned long val,
1569 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);
1578 * call_netdevice_notifiers - call all network notifier blocks
1579 * @val: value passed unmodified to notifier function
1580 * @dev: net_device pointer passed unmodified to notifier function
1582 * Call all network notifier blocks. Parameters and return value
1583 * are as for raw_notifier_call_chain().
1586 int call_netdevice_notifiers(unsigned long val, struct net_device *dev)
1588 struct netdev_notifier_info info;
1590 return call_netdevice_notifiers_info(val, dev, &info);
1592 EXPORT_SYMBOL(call_netdevice_notifiers);
1594 static struct static_key netstamp_needed __read_mostly;
1595 #ifdef HAVE_JUMP_LABEL
1596 /* We are not allowed to call static_key_slow_dec() from irq context
1597 * If net_disable_timestamp() is called from irq context, defer the
1598 * static_key_slow_dec() calls.
1600 static atomic_t netstamp_needed_deferred;
1603 void net_enable_timestamp(void)
1605 #ifdef HAVE_JUMP_LABEL
1606 int deferred = atomic_xchg(&netstamp_needed_deferred, 0);
1610 static_key_slow_dec(&netstamp_needed);
1614 static_key_slow_inc(&netstamp_needed);
1616 EXPORT_SYMBOL(net_enable_timestamp);
1618 void net_disable_timestamp(void)
1620 #ifdef HAVE_JUMP_LABEL
1621 if (in_interrupt()) {
1622 atomic_inc(&netstamp_needed_deferred);
1626 static_key_slow_dec(&netstamp_needed);
1628 EXPORT_SYMBOL(net_disable_timestamp);
1630 static inline void net_timestamp_set(struct sk_buff *skb)
1632 skb->tstamp.tv64 = 0;
1633 if (static_key_false(&netstamp_needed))
1634 __net_timestamp(skb);
1637 #define net_timestamp_check(COND, SKB) \
1638 if (static_key_false(&netstamp_needed)) { \
1639 if ((COND) && !(SKB)->tstamp.tv64) \
1640 __net_timestamp(SKB); \
1643 static inline bool is_skb_forwardable(struct net_device *dev,
1644 struct sk_buff *skb)
1648 if (!(dev->flags & IFF_UP))
1651 len = dev->mtu + dev->hard_header_len + VLAN_HLEN;
1652 if (skb->len <= len)
1655 /* if TSO is enabled, we don't care about the length as the packet
1656 * could be forwarded without being segmented before
1658 if (skb_is_gso(skb))
1665 * dev_forward_skb - loopback an skb to another netif
1667 * @dev: destination network device
1668 * @skb: buffer to forward
1671 * NET_RX_SUCCESS (no congestion)
1672 * NET_RX_DROP (packet was dropped, but freed)
1674 * dev_forward_skb can be used for injecting an skb from the
1675 * start_xmit function of one device into the receive queue
1676 * of another device.
1678 * The receiving device may be in another namespace, so
1679 * we have to clear all information in the skb that could
1680 * impact namespace isolation.
1682 int dev_forward_skb(struct net_device *dev, struct sk_buff *skb)
1684 if (skb_shinfo(skb)->tx_flags & SKBTX_DEV_ZEROCOPY) {
1685 if (skb_copy_ubufs(skb, GFP_ATOMIC)) {
1686 atomic_long_inc(&dev->rx_dropped);
1692 if (unlikely(!is_skb_forwardable(dev, skb))) {
1693 atomic_long_inc(&dev->rx_dropped);
1698 skb_scrub_packet(skb, true);
1699 skb->protocol = eth_type_trans(skb, dev);
1701 return netif_rx(skb);
1703 EXPORT_SYMBOL_GPL(dev_forward_skb);
1705 static inline int deliver_skb(struct sk_buff *skb,
1706 struct packet_type *pt_prev,
1707 struct net_device *orig_dev)
1709 if (unlikely(skb_orphan_frags(skb, GFP_ATOMIC)))
1711 atomic_inc(&skb->users);
1712 return pt_prev->func(skb, skb->dev, pt_prev, orig_dev);
1715 static inline bool skb_loop_sk(struct packet_type *ptype, struct sk_buff *skb)
1717 if (!ptype->af_packet_priv || !skb->sk)
1720 if (ptype->id_match)
1721 return ptype->id_match(ptype, skb->sk);
1722 else if ((struct sock *)ptype->af_packet_priv == skb->sk)
1729 * Support routine. Sends outgoing frames to any network
1730 * taps currently in use.
1733 static void dev_queue_xmit_nit(struct sk_buff *skb, struct net_device *dev)
1735 struct packet_type *ptype;
1736 struct sk_buff *skb2 = NULL;
1737 struct packet_type *pt_prev = NULL;
1740 list_for_each_entry_rcu(ptype, &ptype_all, list) {
1741 /* Never send packets back to the socket
1742 * they originated from - MvS (miquels@drinkel.ow.org)
1744 if ((ptype->dev == dev || !ptype->dev) &&
1745 (!skb_loop_sk(ptype, skb))) {
1747 deliver_skb(skb2, pt_prev, skb->dev);
1752 skb2 = skb_clone(skb, GFP_ATOMIC);
1756 net_timestamp_set(skb2);
1758 /* skb->nh should be correctly
1759 set by sender, so that the second statement is
1760 just protection against buggy protocols.
1762 skb_reset_mac_header(skb2);
1764 if (skb_network_header(skb2) < skb2->data ||
1765 skb_network_header(skb2) > skb_tail_pointer(skb2)) {
1766 net_crit_ratelimited("protocol %04x is buggy, dev %s\n",
1767 ntohs(skb2->protocol),
1769 skb_reset_network_header(skb2);
1772 skb2->transport_header = skb2->network_header;
1773 skb2->pkt_type = PACKET_OUTGOING;
1778 pt_prev->func(skb2, skb->dev, pt_prev, skb->dev);
1783 * netif_setup_tc - Handle tc mappings on real_num_tx_queues change
1784 * @dev: Network device
1785 * @txq: number of queues available
1787 * If real_num_tx_queues is changed the tc mappings may no longer be
1788 * valid. To resolve this verify the tc mapping remains valid and if
1789 * not NULL the mapping. With no priorities mapping to this
1790 * offset/count pair it will no longer be used. In the worst case TC0
1791 * is invalid nothing can be done so disable priority mappings. If is
1792 * expected that drivers will fix this mapping if they can before
1793 * calling netif_set_real_num_tx_queues.
1795 static void netif_setup_tc(struct net_device *dev, unsigned int txq)
1798 struct netdev_tc_txq *tc = &dev->tc_to_txq[0];
1800 /* If TC0 is invalidated disable TC mapping */
1801 if (tc->offset + tc->count > txq) {
1802 pr_warn("Number of in use tx queues changed invalidating tc mappings. Priority traffic classification disabled!\n");
1807 /* Invalidated prio to tc mappings set to TC0 */
1808 for (i = 1; i < TC_BITMASK + 1; i++) {
1809 int q = netdev_get_prio_tc_map(dev, i);
1811 tc = &dev->tc_to_txq[q];
1812 if (tc->offset + tc->count > txq) {
1813 pr_warn("Number of in use tx queues changed. Priority %i to tc mapping %i is no longer valid. Setting map to 0\n",
1815 netdev_set_prio_tc_map(dev, i, 0);
1821 static DEFINE_MUTEX(xps_map_mutex);
1822 #define xmap_dereference(P) \
1823 rcu_dereference_protected((P), lockdep_is_held(&xps_map_mutex))
1825 static struct xps_map *remove_xps_queue(struct xps_dev_maps *dev_maps,
1828 struct xps_map *map = NULL;
1832 map = xmap_dereference(dev_maps->cpu_map[cpu]);
1834 for (pos = 0; map && pos < map->len; pos++) {
1835 if (map->queues[pos] == index) {
1837 map->queues[pos] = map->queues[--map->len];
1839 RCU_INIT_POINTER(dev_maps->cpu_map[cpu], NULL);
1840 kfree_rcu(map, rcu);
1850 static void netif_reset_xps_queues_gt(struct net_device *dev, u16 index)
1852 struct xps_dev_maps *dev_maps;
1854 bool active = false;
1856 mutex_lock(&xps_map_mutex);
1857 dev_maps = xmap_dereference(dev->xps_maps);
1862 for_each_possible_cpu(cpu) {
1863 for (i = index; i < dev->num_tx_queues; i++) {
1864 if (!remove_xps_queue(dev_maps, cpu, i))
1867 if (i == dev->num_tx_queues)
1872 RCU_INIT_POINTER(dev->xps_maps, NULL);
1873 kfree_rcu(dev_maps, rcu);
1876 for (i = index; i < dev->num_tx_queues; i++)
1877 netdev_queue_numa_node_write(netdev_get_tx_queue(dev, i),
1881 mutex_unlock(&xps_map_mutex);
1884 static struct xps_map *expand_xps_map(struct xps_map *map,
1887 struct xps_map *new_map;
1888 int alloc_len = XPS_MIN_MAP_ALLOC;
1891 for (pos = 0; map && pos < map->len; pos++) {
1892 if (map->queues[pos] != index)
1897 /* Need to add queue to this CPU's existing map */
1899 if (pos < map->alloc_len)
1902 alloc_len = map->alloc_len * 2;
1905 /* Need to allocate new map to store queue on this CPU's map */
1906 new_map = kzalloc_node(XPS_MAP_SIZE(alloc_len), GFP_KERNEL,
1911 for (i = 0; i < pos; i++)
1912 new_map->queues[i] = map->queues[i];
1913 new_map->alloc_len = alloc_len;
1919 int netif_set_xps_queue(struct net_device *dev, const struct cpumask *mask,
1922 struct xps_dev_maps *dev_maps, *new_dev_maps = NULL;
1923 struct xps_map *map, *new_map;
1924 int maps_sz = max_t(unsigned int, XPS_DEV_MAPS_SIZE, L1_CACHE_BYTES);
1925 int cpu, numa_node_id = -2;
1926 bool active = false;
1928 mutex_lock(&xps_map_mutex);
1930 dev_maps = xmap_dereference(dev->xps_maps);
1932 /* allocate memory for queue storage */
1933 for_each_online_cpu(cpu) {
1934 if (!cpumask_test_cpu(cpu, mask))
1938 new_dev_maps = kzalloc(maps_sz, GFP_KERNEL);
1939 if (!new_dev_maps) {
1940 mutex_unlock(&xps_map_mutex);
1944 map = dev_maps ? xmap_dereference(dev_maps->cpu_map[cpu]) :
1947 map = expand_xps_map(map, cpu, index);
1951 RCU_INIT_POINTER(new_dev_maps->cpu_map[cpu], map);
1955 goto out_no_new_maps;
1957 for_each_possible_cpu(cpu) {
1958 if (cpumask_test_cpu(cpu, mask) && cpu_online(cpu)) {
1959 /* add queue to CPU maps */
1962 map = xmap_dereference(new_dev_maps->cpu_map[cpu]);
1963 while ((pos < map->len) && (map->queues[pos] != index))
1966 if (pos == map->len)
1967 map->queues[map->len++] = index;
1969 if (numa_node_id == -2)
1970 numa_node_id = cpu_to_node(cpu);
1971 else if (numa_node_id != cpu_to_node(cpu))
1974 } else if (dev_maps) {
1975 /* fill in the new device map from the old device map */
1976 map = xmap_dereference(dev_maps->cpu_map[cpu]);
1977 RCU_INIT_POINTER(new_dev_maps->cpu_map[cpu], map);
1982 rcu_assign_pointer(dev->xps_maps, new_dev_maps);
1984 /* Cleanup old maps */
1986 for_each_possible_cpu(cpu) {
1987 new_map = xmap_dereference(new_dev_maps->cpu_map[cpu]);
1988 map = xmap_dereference(dev_maps->cpu_map[cpu]);
1989 if (map && map != new_map)
1990 kfree_rcu(map, rcu);
1993 kfree_rcu(dev_maps, rcu);
1996 dev_maps = new_dev_maps;
2000 /* update Tx queue numa node */
2001 netdev_queue_numa_node_write(netdev_get_tx_queue(dev, index),
2002 (numa_node_id >= 0) ? numa_node_id :
2008 /* removes queue from unused CPUs */
2009 for_each_possible_cpu(cpu) {
2010 if (cpumask_test_cpu(cpu, mask) && cpu_online(cpu))
2013 if (remove_xps_queue(dev_maps, cpu, index))
2017 /* free map if not active */
2019 RCU_INIT_POINTER(dev->xps_maps, NULL);
2020 kfree_rcu(dev_maps, rcu);
2024 mutex_unlock(&xps_map_mutex);
2028 /* remove any maps that we added */
2029 for_each_possible_cpu(cpu) {
2030 new_map = xmap_dereference(new_dev_maps->cpu_map[cpu]);
2031 map = dev_maps ? xmap_dereference(dev_maps->cpu_map[cpu]) :
2033 if (new_map && new_map != map)
2037 mutex_unlock(&xps_map_mutex);
2039 kfree(new_dev_maps);
2042 EXPORT_SYMBOL(netif_set_xps_queue);
2046 * Routine to help set real_num_tx_queues. To avoid skbs mapped to queues
2047 * greater then real_num_tx_queues stale skbs on the qdisc must be flushed.
2049 int netif_set_real_num_tx_queues(struct net_device *dev, unsigned int txq)
2053 if (txq < 1 || txq > dev->num_tx_queues)
2056 if (dev->reg_state == NETREG_REGISTERED ||
2057 dev->reg_state == NETREG_UNREGISTERING) {
2060 rc = netdev_queue_update_kobjects(dev, dev->real_num_tx_queues,
2066 netif_setup_tc(dev, txq);
2068 if (txq < dev->real_num_tx_queues) {
2069 qdisc_reset_all_tx_gt(dev, txq);
2071 netif_reset_xps_queues_gt(dev, txq);
2076 dev->real_num_tx_queues = txq;
2079 EXPORT_SYMBOL(netif_set_real_num_tx_queues);
2083 * netif_set_real_num_rx_queues - set actual number of RX queues used
2084 * @dev: Network device
2085 * @rxq: Actual number of RX queues
2087 * This must be called either with the rtnl_lock held or before
2088 * registration of the net device. Returns 0 on success, or a
2089 * negative error code. If called before registration, it always
2092 int netif_set_real_num_rx_queues(struct net_device *dev, unsigned int rxq)
2096 if (rxq < 1 || rxq > dev->num_rx_queues)
2099 if (dev->reg_state == NETREG_REGISTERED) {
2102 rc = net_rx_queue_update_kobjects(dev, dev->real_num_rx_queues,
2108 dev->real_num_rx_queues = rxq;
2111 EXPORT_SYMBOL(netif_set_real_num_rx_queues);
2115 * netif_get_num_default_rss_queues - default number of RSS queues
2117 * This routine should set an upper limit on the number of RSS queues
2118 * used by default by multiqueue devices.
2120 int netif_get_num_default_rss_queues(void)
2122 return min_t(int, DEFAULT_MAX_NUM_RSS_QUEUES, num_online_cpus());
2124 EXPORT_SYMBOL(netif_get_num_default_rss_queues);
2126 static inline void __netif_reschedule(struct Qdisc *q)
2128 struct softnet_data *sd;
2129 unsigned long flags;
2131 local_irq_save(flags);
2132 sd = &__get_cpu_var(softnet_data);
2133 q->next_sched = NULL;
2134 *sd->output_queue_tailp = q;
2135 sd->output_queue_tailp = &q->next_sched;
2136 raise_softirq_irqoff(NET_TX_SOFTIRQ);
2137 local_irq_restore(flags);
2140 void __netif_schedule(struct Qdisc *q)
2142 if (!test_and_set_bit(__QDISC_STATE_SCHED, &q->state))
2143 __netif_reschedule(q);
2145 EXPORT_SYMBOL(__netif_schedule);
2147 struct dev_kfree_skb_cb {
2148 enum skb_free_reason reason;
2151 static struct dev_kfree_skb_cb *get_kfree_skb_cb(const struct sk_buff *skb)
2153 return (struct dev_kfree_skb_cb *)skb->cb;
2156 void __dev_kfree_skb_irq(struct sk_buff *skb, enum skb_free_reason reason)
2158 unsigned long flags;
2160 if (likely(atomic_read(&skb->users) == 1)) {
2162 atomic_set(&skb->users, 0);
2163 } else if (likely(!atomic_dec_and_test(&skb->users))) {
2166 get_kfree_skb_cb(skb)->reason = reason;
2167 local_irq_save(flags);
2168 skb->next = __this_cpu_read(softnet_data.completion_queue);
2169 __this_cpu_write(softnet_data.completion_queue, skb);
2170 raise_softirq_irqoff(NET_TX_SOFTIRQ);
2171 local_irq_restore(flags);
2173 EXPORT_SYMBOL(__dev_kfree_skb_irq);
2175 void __dev_kfree_skb_any(struct sk_buff *skb, enum skb_free_reason reason)
2177 if (in_irq() || irqs_disabled())
2178 __dev_kfree_skb_irq(skb, reason);
2182 EXPORT_SYMBOL(__dev_kfree_skb_any);
2186 * netif_device_detach - mark device as removed
2187 * @dev: network device
2189 * Mark device as removed from system and therefore no longer available.
2191 void netif_device_detach(struct net_device *dev)
2193 if (test_and_clear_bit(__LINK_STATE_PRESENT, &dev->state) &&
2194 netif_running(dev)) {
2195 netif_tx_stop_all_queues(dev);
2198 EXPORT_SYMBOL(netif_device_detach);
2201 * netif_device_attach - mark device as attached
2202 * @dev: network device
2204 * Mark device as attached from system and restart if needed.
2206 void netif_device_attach(struct net_device *dev)
2208 if (!test_and_set_bit(__LINK_STATE_PRESENT, &dev->state) &&
2209 netif_running(dev)) {
2210 netif_tx_wake_all_queues(dev);
2211 __netdev_watchdog_up(dev);
2214 EXPORT_SYMBOL(netif_device_attach);
2216 static void skb_warn_bad_offload(const struct sk_buff *skb)
2218 static const netdev_features_t null_features = 0;
2219 struct net_device *dev = skb->dev;
2220 const char *driver = "";
2222 if (!net_ratelimit())
2225 if (dev && dev->dev.parent)
2226 driver = dev_driver_string(dev->dev.parent);
2228 WARN(1, "%s: caps=(%pNF, %pNF) len=%d data_len=%d gso_size=%d "
2229 "gso_type=%d ip_summed=%d\n",
2230 driver, dev ? &dev->features : &null_features,
2231 skb->sk ? &skb->sk->sk_route_caps : &null_features,
2232 skb->len, skb->data_len, skb_shinfo(skb)->gso_size,
2233 skb_shinfo(skb)->gso_type, skb->ip_summed);
2237 * Invalidate hardware checksum when packet is to be mangled, and
2238 * complete checksum manually on outgoing path.
2240 int skb_checksum_help(struct sk_buff *skb)
2243 int ret = 0, offset;
2245 if (skb->ip_summed == CHECKSUM_COMPLETE)
2246 goto out_set_summed;
2248 if (unlikely(skb_shinfo(skb)->gso_size)) {
2249 skb_warn_bad_offload(skb);
2253 /* Before computing a checksum, we should make sure no frag could
2254 * be modified by an external entity : checksum could be wrong.
2256 if (skb_has_shared_frag(skb)) {
2257 ret = __skb_linearize(skb);
2262 offset = skb_checksum_start_offset(skb);
2263 BUG_ON(offset >= skb_headlen(skb));
2264 csum = skb_checksum(skb, offset, skb->len - offset, 0);
2266 offset += skb->csum_offset;
2267 BUG_ON(offset + sizeof(__sum16) > skb_headlen(skb));
2269 if (skb_cloned(skb) &&
2270 !skb_clone_writable(skb, offset + sizeof(__sum16))) {
2271 ret = pskb_expand_head(skb, 0, 0, GFP_ATOMIC);
2276 *(__sum16 *)(skb->data + offset) = csum_fold(csum);
2278 skb->ip_summed = CHECKSUM_NONE;
2282 EXPORT_SYMBOL(skb_checksum_help);
2284 __be16 skb_network_protocol(struct sk_buff *skb)
2286 __be16 type = skb->protocol;
2287 int vlan_depth = ETH_HLEN;
2289 /* Tunnel gso handlers can set protocol to ethernet. */
2290 if (type == htons(ETH_P_TEB)) {
2293 if (unlikely(!pskb_may_pull(skb, sizeof(struct ethhdr))))
2296 eth = (struct ethhdr *)skb_mac_header(skb);
2297 type = eth->h_proto;
2300 while (type == htons(ETH_P_8021Q) || type == htons(ETH_P_8021AD)) {
2301 struct vlan_hdr *vh;
2303 if (unlikely(!pskb_may_pull(skb, vlan_depth + VLAN_HLEN)))
2306 vh = (struct vlan_hdr *)(skb->data + vlan_depth);
2307 type = vh->h_vlan_encapsulated_proto;
2308 vlan_depth += VLAN_HLEN;
2315 * skb_mac_gso_segment - mac layer segmentation handler.
2316 * @skb: buffer to segment
2317 * @features: features for the output path (see dev->features)
2319 struct sk_buff *skb_mac_gso_segment(struct sk_buff *skb,
2320 netdev_features_t features)
2322 struct sk_buff *segs = ERR_PTR(-EPROTONOSUPPORT);
2323 struct packet_offload *ptype;
2324 __be16 type = skb_network_protocol(skb);
2326 if (unlikely(!type))
2327 return ERR_PTR(-EINVAL);
2329 __skb_pull(skb, skb->mac_len);
2332 list_for_each_entry_rcu(ptype, &offload_base, list) {
2333 if (ptype->type == type && ptype->callbacks.gso_segment) {
2334 if (unlikely(skb->ip_summed != CHECKSUM_PARTIAL)) {
2337 err = ptype->callbacks.gso_send_check(skb);
2338 segs = ERR_PTR(err);
2339 if (err || skb_gso_ok(skb, features))
2341 __skb_push(skb, (skb->data -
2342 skb_network_header(skb)));
2344 segs = ptype->callbacks.gso_segment(skb, features);
2350 __skb_push(skb, skb->data - skb_mac_header(skb));
2354 EXPORT_SYMBOL(skb_mac_gso_segment);
2357 /* openvswitch calls this on rx path, so we need a different check.
2359 static inline bool skb_needs_check(struct sk_buff *skb, bool tx_path)
2362 return skb->ip_summed != CHECKSUM_PARTIAL;
2364 return skb->ip_summed == CHECKSUM_NONE;
2368 * __skb_gso_segment - Perform segmentation on skb.
2369 * @skb: buffer to segment
2370 * @features: features for the output path (see dev->features)
2371 * @tx_path: whether it is called in TX path
2373 * This function segments the given skb and returns a list of segments.
2375 * It may return NULL if the skb requires no segmentation. This is
2376 * only possible when GSO is used for verifying header integrity.
2378 struct sk_buff *__skb_gso_segment(struct sk_buff *skb,
2379 netdev_features_t features, bool tx_path)
2381 if (unlikely(skb_needs_check(skb, tx_path))) {
2384 skb_warn_bad_offload(skb);
2386 if (skb_header_cloned(skb) &&
2387 (err = pskb_expand_head(skb, 0, 0, GFP_ATOMIC)))
2388 return ERR_PTR(err);
2391 SKB_GSO_CB(skb)->mac_offset = skb_headroom(skb);
2392 SKB_GSO_CB(skb)->encap_level = 0;
2394 skb_reset_mac_header(skb);
2395 skb_reset_mac_len(skb);
2397 return skb_mac_gso_segment(skb, features);
2399 EXPORT_SYMBOL(__skb_gso_segment);
2401 /* Take action when hardware reception checksum errors are detected. */
2403 void netdev_rx_csum_fault(struct net_device *dev)
2405 if (net_ratelimit()) {
2406 pr_err("%s: hw csum failure\n", dev ? dev->name : "<unknown>");
2410 EXPORT_SYMBOL(netdev_rx_csum_fault);
2413 /* Actually, we should eliminate this check as soon as we know, that:
2414 * 1. IOMMU is present and allows to map all the memory.
2415 * 2. No high memory really exists on this machine.
2418 static int illegal_highdma(struct net_device *dev, struct sk_buff *skb)
2420 #ifdef CONFIG_HIGHMEM
2422 if (!(dev->features & NETIF_F_HIGHDMA)) {
2423 for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
2424 skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
2425 if (PageHighMem(skb_frag_page(frag)))
2430 if (PCI_DMA_BUS_IS_PHYS) {
2431 struct device *pdev = dev->dev.parent;
2435 for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
2436 skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
2437 dma_addr_t addr = page_to_phys(skb_frag_page(frag));
2438 if (!pdev->dma_mask || addr + PAGE_SIZE - 1 > *pdev->dma_mask)
2447 void (*destructor)(struct sk_buff *skb);
2450 #define DEV_GSO_CB(skb) ((struct dev_gso_cb *)(skb)->cb)
2452 static void dev_gso_skb_destructor(struct sk_buff *skb)
2454 struct dev_gso_cb *cb;
2456 kfree_skb_list(skb->next);
2459 cb = DEV_GSO_CB(skb);
2461 cb->destructor(skb);
2465 * dev_gso_segment - Perform emulated hardware segmentation on skb.
2466 * @skb: buffer to segment
2467 * @features: device features as applicable to this skb
2469 * This function segments the given skb and stores the list of segments
2472 static int dev_gso_segment(struct sk_buff *skb, netdev_features_t features)
2474 struct sk_buff *segs;
2476 segs = skb_gso_segment(skb, features);
2478 /* Verifying header integrity only. */
2483 return PTR_ERR(segs);
2486 DEV_GSO_CB(skb)->destructor = skb->destructor;
2487 skb->destructor = dev_gso_skb_destructor;
2492 static netdev_features_t harmonize_features(struct sk_buff *skb,
2493 netdev_features_t features)
2495 if (skb->ip_summed != CHECKSUM_NONE &&
2496 !can_checksum_protocol(features, skb_network_protocol(skb))) {
2497 features &= ~NETIF_F_ALL_CSUM;
2498 } else if (illegal_highdma(skb->dev, skb)) {
2499 features &= ~NETIF_F_SG;
2505 netdev_features_t netif_skb_features(struct sk_buff *skb)
2507 __be16 protocol = skb->protocol;
2508 netdev_features_t features = skb->dev->features;
2510 if (skb_shinfo(skb)->gso_segs > skb->dev->gso_max_segs)
2511 features &= ~NETIF_F_GSO_MASK;
2513 if (protocol == htons(ETH_P_8021Q) || protocol == htons(ETH_P_8021AD)) {
2514 struct vlan_ethhdr *veh = (struct vlan_ethhdr *)skb->data;
2515 protocol = veh->h_vlan_encapsulated_proto;
2516 } else if (!vlan_tx_tag_present(skb)) {
2517 return harmonize_features(skb, features);
2520 features &= (skb->dev->vlan_features | NETIF_F_HW_VLAN_CTAG_TX |
2521 NETIF_F_HW_VLAN_STAG_TX);
2523 if (protocol == htons(ETH_P_8021Q) || protocol == htons(ETH_P_8021AD))
2524 features &= NETIF_F_SG | NETIF_F_HIGHDMA | NETIF_F_FRAGLIST |
2525 NETIF_F_GEN_CSUM | NETIF_F_HW_VLAN_CTAG_TX |
2526 NETIF_F_HW_VLAN_STAG_TX;
2528 return harmonize_features(skb, features);
2530 EXPORT_SYMBOL(netif_skb_features);
2532 int dev_hard_start_xmit(struct sk_buff *skb, struct net_device *dev,
2533 struct netdev_queue *txq)
2535 const struct net_device_ops *ops = dev->netdev_ops;
2536 int rc = NETDEV_TX_OK;
2537 unsigned int skb_len;
2539 if (likely(!skb->next)) {
2540 netdev_features_t features;
2543 * If device doesn't need skb->dst, release it right now while
2544 * its hot in this cpu cache
2546 if (dev->priv_flags & IFF_XMIT_DST_RELEASE)
2549 features = netif_skb_features(skb);
2551 if (vlan_tx_tag_present(skb) &&
2552 !vlan_hw_offload_capable(features, skb->vlan_proto)) {
2553 skb = __vlan_put_tag(skb, skb->vlan_proto,
2554 vlan_tx_tag_get(skb));
2561 /* If encapsulation offload request, verify we are testing
2562 * hardware encapsulation features instead of standard
2563 * features for the netdev
2565 if (skb->encapsulation)
2566 features &= dev->hw_enc_features;
2568 if (netif_needs_gso(skb, features)) {
2569 if (unlikely(dev_gso_segment(skb, features)))
2574 if (skb_needs_linearize(skb, features) &&
2575 __skb_linearize(skb))
2578 /* If packet is not checksummed and device does not
2579 * support checksumming for this protocol, complete
2580 * checksumming here.
2582 if (skb->ip_summed == CHECKSUM_PARTIAL) {
2583 if (skb->encapsulation)
2584 skb_set_inner_transport_header(skb,
2585 skb_checksum_start_offset(skb));
2587 skb_set_transport_header(skb,
2588 skb_checksum_start_offset(skb));
2589 if (!(features & NETIF_F_ALL_CSUM) &&
2590 skb_checksum_help(skb))
2595 if (!list_empty(&ptype_all))
2596 dev_queue_xmit_nit(skb, dev);
2599 rc = ops->ndo_start_xmit(skb, dev);
2601 trace_net_dev_xmit(skb, rc, dev, skb_len);
2602 if (rc == NETDEV_TX_OK)
2603 txq_trans_update(txq);
2609 struct sk_buff *nskb = skb->next;
2611 skb->next = nskb->next;
2614 if (!list_empty(&ptype_all))
2615 dev_queue_xmit_nit(nskb, dev);
2617 skb_len = nskb->len;
2618 rc = ops->ndo_start_xmit(nskb, dev);
2619 trace_net_dev_xmit(nskb, rc, dev, skb_len);
2620 if (unlikely(rc != NETDEV_TX_OK)) {
2621 if (rc & ~NETDEV_TX_MASK)
2622 goto out_kfree_gso_skb;
2623 nskb->next = skb->next;
2627 txq_trans_update(txq);
2628 if (unlikely(netif_xmit_stopped(txq) && skb->next))
2629 return NETDEV_TX_BUSY;
2630 } while (skb->next);
2633 if (likely(skb->next == NULL)) {
2634 skb->destructor = DEV_GSO_CB(skb)->destructor;
2643 EXPORT_SYMBOL_GPL(dev_hard_start_xmit);
2645 static void qdisc_pkt_len_init(struct sk_buff *skb)
2647 const struct skb_shared_info *shinfo = skb_shinfo(skb);
2649 qdisc_skb_cb(skb)->pkt_len = skb->len;
2651 /* To get more precise estimation of bytes sent on wire,
2652 * we add to pkt_len the headers size of all segments
2654 if (shinfo->gso_size) {
2655 unsigned int hdr_len;
2656 u16 gso_segs = shinfo->gso_segs;
2658 /* mac layer + network layer */
2659 hdr_len = skb_transport_header(skb) - skb_mac_header(skb);
2661 /* + transport layer */
2662 if (likely(shinfo->gso_type & (SKB_GSO_TCPV4 | SKB_GSO_TCPV6)))
2663 hdr_len += tcp_hdrlen(skb);
2665 hdr_len += sizeof(struct udphdr);
2667 if (shinfo->gso_type & SKB_GSO_DODGY)
2668 gso_segs = DIV_ROUND_UP(skb->len - hdr_len,
2671 qdisc_skb_cb(skb)->pkt_len += (gso_segs - 1) * hdr_len;
2675 static inline int __dev_xmit_skb(struct sk_buff *skb, struct Qdisc *q,
2676 struct net_device *dev,
2677 struct netdev_queue *txq)
2679 spinlock_t *root_lock = qdisc_lock(q);
2683 qdisc_pkt_len_init(skb);
2684 qdisc_calculate_pkt_len(skb, q);
2686 * Heuristic to force contended enqueues to serialize on a
2687 * separate lock before trying to get qdisc main lock.
2688 * This permits __QDISC_STATE_RUNNING owner to get the lock more often
2689 * and dequeue packets faster.
2691 contended = qdisc_is_running(q);
2692 if (unlikely(contended))
2693 spin_lock(&q->busylock);
2695 spin_lock(root_lock);
2696 if (unlikely(test_bit(__QDISC_STATE_DEACTIVATED, &q->state))) {
2699 } else if ((q->flags & TCQ_F_CAN_BYPASS) && !qdisc_qlen(q) &&
2700 qdisc_run_begin(q)) {
2702 * This is a work-conserving queue; there are no old skbs
2703 * waiting to be sent out; and the qdisc is not running -
2704 * xmit the skb directly.
2706 if (!(dev->priv_flags & IFF_XMIT_DST_RELEASE))
2709 qdisc_bstats_update(q, skb);
2711 if (sch_direct_xmit(skb, q, dev, txq, root_lock)) {
2712 if (unlikely(contended)) {
2713 spin_unlock(&q->busylock);
2720 rc = NET_XMIT_SUCCESS;
2723 rc = q->enqueue(skb, q) & NET_XMIT_MASK;
2724 if (qdisc_run_begin(q)) {
2725 if (unlikely(contended)) {
2726 spin_unlock(&q->busylock);
2732 spin_unlock(root_lock);
2733 if (unlikely(contended))
2734 spin_unlock(&q->busylock);
2738 #if IS_ENABLED(CONFIG_CGROUP_NET_PRIO)
2739 static void skb_update_prio(struct sk_buff *skb)
2741 struct netprio_map *map = rcu_dereference_bh(skb->dev->priomap);
2743 if (!skb->priority && skb->sk && map) {
2744 unsigned int prioidx = skb->sk->sk_cgrp_prioidx;
2746 if (prioidx < map->priomap_len)
2747 skb->priority = map->priomap[prioidx];
2751 #define skb_update_prio(skb)
2754 static DEFINE_PER_CPU(int, xmit_recursion);
2755 #define RECURSION_LIMIT 10
2758 * dev_loopback_xmit - loop back @skb
2759 * @skb: buffer to transmit
2761 int dev_loopback_xmit(struct sk_buff *skb)
2763 skb_reset_mac_header(skb);
2764 __skb_pull(skb, skb_network_offset(skb));
2765 skb->pkt_type = PACKET_LOOPBACK;
2766 skb->ip_summed = CHECKSUM_UNNECESSARY;
2767 WARN_ON(!skb_dst(skb));
2772 EXPORT_SYMBOL(dev_loopback_xmit);
2775 * dev_queue_xmit - transmit a buffer
2776 * @skb: buffer to transmit
2778 * Queue a buffer for transmission to a network device. The caller must
2779 * have set the device and priority and built the buffer before calling
2780 * this function. The function can be called from an interrupt.
2782 * A negative errno code is returned on a failure. A success does not
2783 * guarantee the frame will be transmitted as it may be dropped due
2784 * to congestion or traffic shaping.
2786 * -----------------------------------------------------------------------------------
2787 * I notice this method can also return errors from the queue disciplines,
2788 * including NET_XMIT_DROP, which is a positive value. So, errors can also
2791 * Regardless of the return value, the skb is consumed, so it is currently
2792 * difficult to retry a send to this method. (You can bump the ref count
2793 * before sending to hold a reference for retry if you are careful.)
2795 * When calling this method, interrupts MUST be enabled. This is because
2796 * the BH enable code must have IRQs enabled so that it will not deadlock.
2799 int __dev_queue_xmit(struct sk_buff *skb, void *accel_priv)
2801 struct net_device *dev = skb->dev;
2802 struct netdev_queue *txq;
2806 skb_reset_mac_header(skb);
2808 /* Disable soft irqs for various locks below. Also
2809 * stops preemption for RCU.
2813 skb_update_prio(skb);
2815 txq = netdev_pick_tx(dev, skb, accel_priv);
2816 q = rcu_dereference_bh(txq->qdisc);
2818 #ifdef CONFIG_NET_CLS_ACT
2819 skb->tc_verd = SET_TC_AT(skb->tc_verd, AT_EGRESS);
2821 trace_net_dev_queue(skb);
2823 rc = __dev_xmit_skb(skb, q, dev, txq);
2827 /* The device has no queue. Common case for software devices:
2828 loopback, all the sorts of tunnels...
2830 Really, it is unlikely that netif_tx_lock protection is necessary
2831 here. (f.e. loopback and IP tunnels are clean ignoring statistics
2833 However, it is possible, that they rely on protection
2836 Check this and shot the lock. It is not prone from deadlocks.
2837 Either shot noqueue qdisc, it is even simpler 8)
2839 if (dev->flags & IFF_UP) {
2840 int cpu = smp_processor_id(); /* ok because BHs are off */
2842 if (txq->xmit_lock_owner != cpu) {
2844 if (__this_cpu_read(xmit_recursion) > RECURSION_LIMIT)
2845 goto recursion_alert;
2847 HARD_TX_LOCK(dev, txq, cpu);
2849 if (!netif_xmit_stopped(txq)) {
2850 __this_cpu_inc(xmit_recursion);
2851 rc = dev_hard_start_xmit(skb, dev, txq);
2852 __this_cpu_dec(xmit_recursion);
2853 if (dev_xmit_complete(rc)) {
2854 HARD_TX_UNLOCK(dev, txq);
2858 HARD_TX_UNLOCK(dev, txq);
2859 net_crit_ratelimited("Virtual device %s asks to queue packet!\n",
2862 /* Recursion is detected! It is possible,
2866 net_crit_ratelimited("Dead loop on virtual device %s, fix it urgently!\n",
2872 rcu_read_unlock_bh();
2877 rcu_read_unlock_bh();
2881 int dev_queue_xmit(struct sk_buff *skb)
2883 return __dev_queue_xmit(skb, NULL);
2885 EXPORT_SYMBOL(dev_queue_xmit);
2887 int dev_queue_xmit_accel(struct sk_buff *skb, void *accel_priv)
2889 return __dev_queue_xmit(skb, accel_priv);
2891 EXPORT_SYMBOL(dev_queue_xmit_accel);
2894 /*=======================================================================
2896 =======================================================================*/
2898 int netdev_max_backlog __read_mostly = 1000;
2899 EXPORT_SYMBOL(netdev_max_backlog);
2901 int netdev_tstamp_prequeue __read_mostly = 1;
2902 int netdev_budget __read_mostly = 300;
2903 int weight_p __read_mostly = 64; /* old backlog weight */
2905 /* Called with irq disabled */
2906 static inline void ____napi_schedule(struct softnet_data *sd,
2907 struct napi_struct *napi)
2909 list_add_tail(&napi->poll_list, &sd->poll_list);
2910 __raise_softirq_irqoff(NET_RX_SOFTIRQ);
2915 /* One global table that all flow-based protocols share. */
2916 struct rps_sock_flow_table __rcu *rps_sock_flow_table __read_mostly;
2917 EXPORT_SYMBOL(rps_sock_flow_table);
2919 struct static_key rps_needed __read_mostly;
2921 static struct rps_dev_flow *
2922 set_rps_cpu(struct net_device *dev, struct sk_buff *skb,
2923 struct rps_dev_flow *rflow, u16 next_cpu)
2925 if (next_cpu != RPS_NO_CPU) {
2926 #ifdef CONFIG_RFS_ACCEL
2927 struct netdev_rx_queue *rxqueue;
2928 struct rps_dev_flow_table *flow_table;
2929 struct rps_dev_flow *old_rflow;
2934 /* Should we steer this flow to a different hardware queue? */
2935 if (!skb_rx_queue_recorded(skb) || !dev->rx_cpu_rmap ||
2936 !(dev->features & NETIF_F_NTUPLE))
2938 rxq_index = cpu_rmap_lookup_index(dev->rx_cpu_rmap, next_cpu);
2939 if (rxq_index == skb_get_rx_queue(skb))
2942 rxqueue = dev->_rx + rxq_index;
2943 flow_table = rcu_dereference(rxqueue->rps_flow_table);
2946 flow_id = skb->rxhash & flow_table->mask;
2947 rc = dev->netdev_ops->ndo_rx_flow_steer(dev, skb,
2948 rxq_index, flow_id);
2952 rflow = &flow_table->flows[flow_id];
2954 if (old_rflow->filter == rflow->filter)
2955 old_rflow->filter = RPS_NO_FILTER;
2959 per_cpu(softnet_data, next_cpu).input_queue_head;
2962 rflow->cpu = next_cpu;
2967 * get_rps_cpu is called from netif_receive_skb and returns the target
2968 * CPU from the RPS map of the receiving queue for a given skb.
2969 * rcu_read_lock must be held on entry.
2971 static int get_rps_cpu(struct net_device *dev, struct sk_buff *skb,
2972 struct rps_dev_flow **rflowp)
2974 struct netdev_rx_queue *rxqueue;
2975 struct rps_map *map;
2976 struct rps_dev_flow_table *flow_table;
2977 struct rps_sock_flow_table *sock_flow_table;
2981 if (skb_rx_queue_recorded(skb)) {
2982 u16 index = skb_get_rx_queue(skb);
2983 if (unlikely(index >= dev->real_num_rx_queues)) {
2984 WARN_ONCE(dev->real_num_rx_queues > 1,
2985 "%s received packet on queue %u, but number "
2986 "of RX queues is %u\n",
2987 dev->name, index, dev->real_num_rx_queues);
2990 rxqueue = dev->_rx + index;
2994 map = rcu_dereference(rxqueue->rps_map);
2996 if (map->len == 1 &&
2997 !rcu_access_pointer(rxqueue->rps_flow_table)) {
2998 tcpu = map->cpus[0];
2999 if (cpu_online(tcpu))
3003 } else if (!rcu_access_pointer(rxqueue->rps_flow_table)) {
3007 skb_reset_network_header(skb);
3008 if (!skb_get_hash(skb))
3011 flow_table = rcu_dereference(rxqueue->rps_flow_table);
3012 sock_flow_table = rcu_dereference(rps_sock_flow_table);
3013 if (flow_table && sock_flow_table) {
3015 struct rps_dev_flow *rflow;
3017 rflow = &flow_table->flows[skb->rxhash & flow_table->mask];
3020 next_cpu = sock_flow_table->ents[skb->rxhash &
3021 sock_flow_table->mask];
3024 * If the desired CPU (where last recvmsg was done) is
3025 * different from current CPU (one in the rx-queue flow
3026 * table entry), switch if one of the following holds:
3027 * - Current CPU is unset (equal to RPS_NO_CPU).
3028 * - Current CPU is offline.
3029 * - The current CPU's queue tail has advanced beyond the
3030 * last packet that was enqueued using this table entry.
3031 * This guarantees that all previous packets for the flow
3032 * have been dequeued, thus preserving in order delivery.
3034 if (unlikely(tcpu != next_cpu) &&
3035 (tcpu == RPS_NO_CPU || !cpu_online(tcpu) ||
3036 ((int)(per_cpu(softnet_data, tcpu).input_queue_head -
3037 rflow->last_qtail)) >= 0)) {
3039 rflow = set_rps_cpu(dev, skb, rflow, next_cpu);
3042 if (tcpu != RPS_NO_CPU && cpu_online(tcpu)) {
3050 tcpu = map->cpus[((u64) skb->rxhash * map->len) >> 32];
3052 if (cpu_online(tcpu)) {
3062 #ifdef CONFIG_RFS_ACCEL
3065 * rps_may_expire_flow - check whether an RFS hardware filter may be removed
3066 * @dev: Device on which the filter was set
3067 * @rxq_index: RX queue index
3068 * @flow_id: Flow ID passed to ndo_rx_flow_steer()
3069 * @filter_id: Filter ID returned by ndo_rx_flow_steer()
3071 * Drivers that implement ndo_rx_flow_steer() should periodically call
3072 * this function for each installed filter and remove the filters for
3073 * which it returns %true.
3075 bool rps_may_expire_flow(struct net_device *dev, u16 rxq_index,
3076 u32 flow_id, u16 filter_id)
3078 struct netdev_rx_queue *rxqueue = dev->_rx + rxq_index;
3079 struct rps_dev_flow_table *flow_table;
3080 struct rps_dev_flow *rflow;
3085 flow_table = rcu_dereference(rxqueue->rps_flow_table);
3086 if (flow_table && flow_id <= flow_table->mask) {
3087 rflow = &flow_table->flows[flow_id];
3088 cpu = ACCESS_ONCE(rflow->cpu);
3089 if (rflow->filter == filter_id && cpu != RPS_NO_CPU &&
3090 ((int)(per_cpu(softnet_data, cpu).input_queue_head -
3091 rflow->last_qtail) <
3092 (int)(10 * flow_table->mask)))
3098 EXPORT_SYMBOL(rps_may_expire_flow);
3100 #endif /* CONFIG_RFS_ACCEL */
3102 /* Called from hardirq (IPI) context */
3103 static void rps_trigger_softirq(void *data)
3105 struct softnet_data *sd = data;
3107 ____napi_schedule(sd, &sd->backlog);
3111 #endif /* CONFIG_RPS */
3114 * Check if this softnet_data structure is another cpu one
3115 * If yes, queue it to our IPI list and return 1
3118 static int rps_ipi_queued(struct softnet_data *sd)
3121 struct softnet_data *mysd = &__get_cpu_var(softnet_data);
3124 sd->rps_ipi_next = mysd->rps_ipi_list;
3125 mysd->rps_ipi_list = sd;
3127 __raise_softirq_irqoff(NET_RX_SOFTIRQ);
3130 #endif /* CONFIG_RPS */
3134 #ifdef CONFIG_NET_FLOW_LIMIT
3135 int netdev_flow_limit_table_len __read_mostly = (1 << 12);
3138 static bool skb_flow_limit(struct sk_buff *skb, unsigned int qlen)
3140 #ifdef CONFIG_NET_FLOW_LIMIT
3141 struct sd_flow_limit *fl;
3142 struct softnet_data *sd;
3143 unsigned int old_flow, new_flow;
3145 if (qlen < (netdev_max_backlog >> 1))
3148 sd = &__get_cpu_var(softnet_data);
3151 fl = rcu_dereference(sd->flow_limit);
3153 new_flow = skb_get_hash(skb) & (fl->num_buckets - 1);
3154 old_flow = fl->history[fl->history_head];
3155 fl->history[fl->history_head] = new_flow;
3158 fl->history_head &= FLOW_LIMIT_HISTORY - 1;
3160 if (likely(fl->buckets[old_flow]))
3161 fl->buckets[old_flow]--;
3163 if (++fl->buckets[new_flow] > (FLOW_LIMIT_HISTORY >> 1)) {
3175 * enqueue_to_backlog is called to queue an skb to a per CPU backlog
3176 * queue (may be a remote CPU queue).
3178 static int enqueue_to_backlog(struct sk_buff *skb, int cpu,
3179 unsigned int *qtail)
3181 struct softnet_data *sd;
3182 unsigned long flags;
3185 sd = &per_cpu(softnet_data, cpu);
3187 local_irq_save(flags);
3190 qlen = skb_queue_len(&sd->input_pkt_queue);
3191 if (qlen <= netdev_max_backlog && !skb_flow_limit(skb, qlen)) {
3192 if (skb_queue_len(&sd->input_pkt_queue)) {
3194 __skb_queue_tail(&sd->input_pkt_queue, skb);
3195 input_queue_tail_incr_save(sd, qtail);
3197 local_irq_restore(flags);
3198 return NET_RX_SUCCESS;
3201 /* Schedule NAPI for backlog device
3202 * We can use non atomic operation since we own the queue lock
3204 if (!__test_and_set_bit(NAPI_STATE_SCHED, &sd->backlog.state)) {
3205 if (!rps_ipi_queued(sd))
3206 ____napi_schedule(sd, &sd->backlog);
3214 local_irq_restore(flags);
3216 atomic_long_inc(&skb->dev->rx_dropped);
3222 * netif_rx - post buffer to the network code
3223 * @skb: buffer to post
3225 * This function receives a packet from a device driver and queues it for
3226 * the upper (protocol) levels to process. It always succeeds. The buffer
3227 * may be dropped during processing for congestion control or by the
3231 * NET_RX_SUCCESS (no congestion)
3232 * NET_RX_DROP (packet was dropped)
3236 int netif_rx(struct sk_buff *skb)
3240 /* if netpoll wants it, pretend we never saw it */
3241 if (netpoll_rx(skb))
3244 net_timestamp_check(netdev_tstamp_prequeue, skb);
3246 trace_netif_rx(skb);
3248 if (static_key_false(&rps_needed)) {
3249 struct rps_dev_flow voidflow, *rflow = &voidflow;
3255 cpu = get_rps_cpu(skb->dev, skb, &rflow);
3257 cpu = smp_processor_id();
3259 ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail);
3267 ret = enqueue_to_backlog(skb, get_cpu(), &qtail);
3272 EXPORT_SYMBOL(netif_rx);
3274 int netif_rx_ni(struct sk_buff *skb)
3279 err = netif_rx(skb);
3280 if (local_softirq_pending())
3286 EXPORT_SYMBOL(netif_rx_ni);
3288 static void net_tx_action(struct softirq_action *h)
3290 struct softnet_data *sd = &__get_cpu_var(softnet_data);
3292 if (sd->completion_queue) {
3293 struct sk_buff *clist;
3295 local_irq_disable();
3296 clist = sd->completion_queue;
3297 sd->completion_queue = NULL;
3301 struct sk_buff *skb = clist;
3302 clist = clist->next;
3304 WARN_ON(atomic_read(&skb->users));
3305 if (likely(get_kfree_skb_cb(skb)->reason == SKB_REASON_CONSUMED))
3306 trace_consume_skb(skb);
3308 trace_kfree_skb(skb, net_tx_action);
3313 if (sd->output_queue) {
3316 local_irq_disable();
3317 head = sd->output_queue;
3318 sd->output_queue = NULL;
3319 sd->output_queue_tailp = &sd->output_queue;
3323 struct Qdisc *q = head;
3324 spinlock_t *root_lock;
3326 head = head->next_sched;
3328 root_lock = qdisc_lock(q);
3329 if (spin_trylock(root_lock)) {
3330 smp_mb__before_clear_bit();
3331 clear_bit(__QDISC_STATE_SCHED,
3334 spin_unlock(root_lock);
3336 if (!test_bit(__QDISC_STATE_DEACTIVATED,
3338 __netif_reschedule(q);
3340 smp_mb__before_clear_bit();
3341 clear_bit(__QDISC_STATE_SCHED,
3349 #if (defined(CONFIG_BRIDGE) || defined(CONFIG_BRIDGE_MODULE)) && \
3350 (defined(CONFIG_ATM_LANE) || defined(CONFIG_ATM_LANE_MODULE))
3351 /* This hook is defined here for ATM LANE */
3352 int (*br_fdb_test_addr_hook)(struct net_device *dev,
3353 unsigned char *addr) __read_mostly;
3354 EXPORT_SYMBOL_GPL(br_fdb_test_addr_hook);
3357 #ifdef CONFIG_NET_CLS_ACT
3358 /* TODO: Maybe we should just force sch_ingress to be compiled in
3359 * when CONFIG_NET_CLS_ACT is? otherwise some useless instructions
3360 * a compare and 2 stores extra right now if we dont have it on
3361 * but have CONFIG_NET_CLS_ACT
3362 * NOTE: This doesn't stop any functionality; if you dont have
3363 * the ingress scheduler, you just can't add policies on ingress.
3366 static int ing_filter(struct sk_buff *skb, struct netdev_queue *rxq)
3368 struct net_device *dev = skb->dev;
3369 u32 ttl = G_TC_RTTL(skb->tc_verd);
3370 int result = TC_ACT_OK;
3373 if (unlikely(MAX_RED_LOOP < ttl++)) {
3374 net_warn_ratelimited("Redir loop detected Dropping packet (%d->%d)\n",
3375 skb->skb_iif, dev->ifindex);
3379 skb->tc_verd = SET_TC_RTTL(skb->tc_verd, ttl);
3380 skb->tc_verd = SET_TC_AT(skb->tc_verd, AT_INGRESS);
3383 if (q != &noop_qdisc) {
3384 spin_lock(qdisc_lock(q));
3385 if (likely(!test_bit(__QDISC_STATE_DEACTIVATED, &q->state)))
3386 result = qdisc_enqueue_root(skb, q);
3387 spin_unlock(qdisc_lock(q));
3393 static inline struct sk_buff *handle_ing(struct sk_buff *skb,
3394 struct packet_type **pt_prev,
3395 int *ret, struct net_device *orig_dev)
3397 struct netdev_queue *rxq = rcu_dereference(skb->dev->ingress_queue);
3399 if (!rxq || rxq->qdisc == &noop_qdisc)
3403 *ret = deliver_skb(skb, *pt_prev, orig_dev);
3407 switch (ing_filter(skb, rxq)) {
3421 * netdev_rx_handler_register - register receive handler
3422 * @dev: device to register a handler for
3423 * @rx_handler: receive handler to register
3424 * @rx_handler_data: data pointer that is used by rx handler
3426 * Register a receive hander for a device. This handler will then be
3427 * called from __netif_receive_skb. A negative errno code is returned
3430 * The caller must hold the rtnl_mutex.
3432 * For a general description of rx_handler, see enum rx_handler_result.
3434 int netdev_rx_handler_register(struct net_device *dev,
3435 rx_handler_func_t *rx_handler,
3436 void *rx_handler_data)
3440 if (dev->rx_handler)
3443 /* Note: rx_handler_data must be set before rx_handler */
3444 rcu_assign_pointer(dev->rx_handler_data, rx_handler_data);
3445 rcu_assign_pointer(dev->rx_handler, rx_handler);
3449 EXPORT_SYMBOL_GPL(netdev_rx_handler_register);
3452 * netdev_rx_handler_unregister - unregister receive handler
3453 * @dev: device to unregister a handler from
3455 * Unregister a receive handler from a device.
3457 * The caller must hold the rtnl_mutex.
3459 void netdev_rx_handler_unregister(struct net_device *dev)
3463 RCU_INIT_POINTER(dev->rx_handler, NULL);
3464 /* a reader seeing a non NULL rx_handler in a rcu_read_lock()
3465 * section has a guarantee to see a non NULL rx_handler_data
3469 RCU_INIT_POINTER(dev->rx_handler_data, NULL);
3471 EXPORT_SYMBOL_GPL(netdev_rx_handler_unregister);
3474 * Limit the use of PFMEMALLOC reserves to those protocols that implement
3475 * the special handling of PFMEMALLOC skbs.
3477 static bool skb_pfmemalloc_protocol(struct sk_buff *skb)
3479 switch (skb->protocol) {
3480 case __constant_htons(ETH_P_ARP):
3481 case __constant_htons(ETH_P_IP):
3482 case __constant_htons(ETH_P_IPV6):
3483 case __constant_htons(ETH_P_8021Q):
3484 case __constant_htons(ETH_P_8021AD):
3491 static int __netif_receive_skb_core(struct sk_buff *skb, bool pfmemalloc)
3493 struct packet_type *ptype, *pt_prev;
3494 rx_handler_func_t *rx_handler;
3495 struct net_device *orig_dev;
3496 struct net_device *null_or_dev;
3497 bool deliver_exact = false;
3498 int ret = NET_RX_DROP;
3501 net_timestamp_check(!netdev_tstamp_prequeue, skb);
3503 trace_netif_receive_skb(skb);
3505 /* if we've gotten here through NAPI, check netpoll */
3506 if (netpoll_receive_skb(skb))
3509 orig_dev = skb->dev;
3511 skb_reset_network_header(skb);
3512 if (!skb_transport_header_was_set(skb))
3513 skb_reset_transport_header(skb);
3514 skb_reset_mac_len(skb);
3521 skb->skb_iif = skb->dev->ifindex;
3523 __this_cpu_inc(softnet_data.processed);
3525 if (skb->protocol == cpu_to_be16(ETH_P_8021Q) ||
3526 skb->protocol == cpu_to_be16(ETH_P_8021AD)) {
3527 skb = vlan_untag(skb);
3532 #ifdef CONFIG_NET_CLS_ACT
3533 if (skb->tc_verd & TC_NCLS) {
3534 skb->tc_verd = CLR_TC_NCLS(skb->tc_verd);
3542 list_for_each_entry_rcu(ptype, &ptype_all, list) {
3543 if (!ptype->dev || ptype->dev == skb->dev) {
3545 ret = deliver_skb(skb, pt_prev, orig_dev);
3551 #ifdef CONFIG_NET_CLS_ACT
3552 skb = handle_ing(skb, &pt_prev, &ret, orig_dev);
3558 if (pfmemalloc && !skb_pfmemalloc_protocol(skb))
3561 if (vlan_tx_tag_present(skb)) {
3563 ret = deliver_skb(skb, pt_prev, orig_dev);
3566 if (vlan_do_receive(&skb))
3568 else if (unlikely(!skb))
3572 rx_handler = rcu_dereference(skb->dev->rx_handler);
3575 ret = deliver_skb(skb, pt_prev, orig_dev);
3578 switch (rx_handler(&skb)) {
3579 case RX_HANDLER_CONSUMED:
3580 ret = NET_RX_SUCCESS;
3582 case RX_HANDLER_ANOTHER:
3584 case RX_HANDLER_EXACT:
3585 deliver_exact = true;
3586 case RX_HANDLER_PASS:
3593 if (unlikely(vlan_tx_tag_present(skb))) {
3594 if (vlan_tx_tag_get_id(skb))
3595 skb->pkt_type = PACKET_OTHERHOST;
3596 /* Note: we might in the future use prio bits
3597 * and set skb->priority like in vlan_do_receive()
3598 * For the time being, just ignore Priority Code Point
3603 /* deliver only exact match when indicated */
3604 null_or_dev = deliver_exact ? skb->dev : NULL;
3606 type = skb->protocol;
3607 list_for_each_entry_rcu(ptype,
3608 &ptype_base[ntohs(type) & PTYPE_HASH_MASK], list) {
3609 if (ptype->type == type &&
3610 (ptype->dev == null_or_dev || ptype->dev == skb->dev ||
3611 ptype->dev == orig_dev)) {
3613 ret = deliver_skb(skb, pt_prev, orig_dev);
3619 if (unlikely(skb_orphan_frags(skb, GFP_ATOMIC)))
3622 ret = pt_prev->func(skb, skb->dev, pt_prev, orig_dev);
3625 atomic_long_inc(&skb->dev->rx_dropped);
3627 /* Jamal, now you will not able to escape explaining
3628 * me how you were going to use this. :-)
3639 static int __netif_receive_skb(struct sk_buff *skb)
3643 if (sk_memalloc_socks() && skb_pfmemalloc(skb)) {
3644 unsigned long pflags = current->flags;
3647 * PFMEMALLOC skbs are special, they should
3648 * - be delivered to SOCK_MEMALLOC sockets only
3649 * - stay away from userspace
3650 * - have bounded memory usage
3652 * Use PF_MEMALLOC as this saves us from propagating the allocation
3653 * context down to all allocation sites.
3655 current->flags |= PF_MEMALLOC;
3656 ret = __netif_receive_skb_core(skb, true);
3657 tsk_restore_flags(current, pflags, PF_MEMALLOC);
3659 ret = __netif_receive_skb_core(skb, false);
3665 * netif_receive_skb - process receive buffer from network
3666 * @skb: buffer to process
3668 * netif_receive_skb() is the main receive data processing function.
3669 * It always succeeds. The buffer may be dropped during processing
3670 * for congestion control or by the protocol layers.
3672 * This function may only be called from softirq context and interrupts
3673 * should be enabled.
3675 * Return values (usually ignored):
3676 * NET_RX_SUCCESS: no congestion
3677 * NET_RX_DROP: packet was dropped
3679 int netif_receive_skb(struct sk_buff *skb)
3681 net_timestamp_check(netdev_tstamp_prequeue, skb);
3683 if (skb_defer_rx_timestamp(skb))
3684 return NET_RX_SUCCESS;
3687 if (static_key_false(&rps_needed)) {
3688 struct rps_dev_flow voidflow, *rflow = &voidflow;
3693 cpu = get_rps_cpu(skb->dev, skb, &rflow);
3696 ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail);
3703 return __netif_receive_skb(skb);
3705 EXPORT_SYMBOL(netif_receive_skb);
3707 /* Network device is going away, flush any packets still pending
3708 * Called with irqs disabled.
3710 static void flush_backlog(void *arg)
3712 struct net_device *dev = arg;
3713 struct softnet_data *sd = &__get_cpu_var(softnet_data);
3714 struct sk_buff *skb, *tmp;
3717 skb_queue_walk_safe(&sd->input_pkt_queue, skb, tmp) {
3718 if (skb->dev == dev) {
3719 __skb_unlink(skb, &sd->input_pkt_queue);
3721 input_queue_head_incr(sd);
3726 skb_queue_walk_safe(&sd->process_queue, skb, tmp) {
3727 if (skb->dev == dev) {
3728 __skb_unlink(skb, &sd->process_queue);
3730 input_queue_head_incr(sd);
3735 static int napi_gro_complete(struct sk_buff *skb)
3737 struct packet_offload *ptype;
3738 __be16 type = skb->protocol;
3739 struct list_head *head = &offload_base;
3742 BUILD_BUG_ON(sizeof(struct napi_gro_cb) > sizeof(skb->cb));
3744 if (NAPI_GRO_CB(skb)->count == 1) {
3745 skb_shinfo(skb)->gso_size = 0;
3750 list_for_each_entry_rcu(ptype, head, list) {
3751 if (ptype->type != type || !ptype->callbacks.gro_complete)
3754 err = ptype->callbacks.gro_complete(skb, 0);
3760 WARN_ON(&ptype->list == head);
3762 return NET_RX_SUCCESS;
3766 return netif_receive_skb(skb);
3769 /* napi->gro_list contains packets ordered by age.
3770 * youngest packets at the head of it.
3771 * Complete skbs in reverse order to reduce latencies.
3773 void napi_gro_flush(struct napi_struct *napi, bool flush_old)
3775 struct sk_buff *skb, *prev = NULL;
3777 /* scan list and build reverse chain */
3778 for (skb = napi->gro_list; skb != NULL; skb = skb->next) {
3783 for (skb = prev; skb; skb = prev) {
3786 if (flush_old && NAPI_GRO_CB(skb)->age == jiffies)
3790 napi_gro_complete(skb);
3794 napi->gro_list = NULL;
3796 EXPORT_SYMBOL(napi_gro_flush);
3798 static void gro_list_prepare(struct napi_struct *napi, struct sk_buff *skb)
3801 unsigned int maclen = skb->dev->hard_header_len;
3803 for (p = napi->gro_list; p; p = p->next) {
3804 unsigned long diffs;
3806 diffs = (unsigned long)p->dev ^ (unsigned long)skb->dev;
3807 diffs |= p->vlan_tci ^ skb->vlan_tci;
3808 if (maclen == ETH_HLEN)
3809 diffs |= compare_ether_header(skb_mac_header(p),
3810 skb_gro_mac_header(skb));
3812 diffs = memcmp(skb_mac_header(p),
3813 skb_gro_mac_header(skb),
3815 NAPI_GRO_CB(p)->same_flow = !diffs;
3816 NAPI_GRO_CB(p)->flush = 0;
3820 static void skb_gro_reset_offset(struct sk_buff *skb)
3822 const struct skb_shared_info *pinfo = skb_shinfo(skb);
3823 const skb_frag_t *frag0 = &pinfo->frags[0];
3825 NAPI_GRO_CB(skb)->data_offset = 0;
3826 NAPI_GRO_CB(skb)->frag0 = NULL;
3827 NAPI_GRO_CB(skb)->frag0_len = 0;
3829 if (skb_mac_header(skb) == skb_tail_pointer(skb) &&
3831 !PageHighMem(skb_frag_page(frag0))) {
3832 NAPI_GRO_CB(skb)->frag0 = skb_frag_address(frag0);
3833 NAPI_GRO_CB(skb)->frag0_len = skb_frag_size(frag0);
3837 static enum gro_result dev_gro_receive(struct napi_struct *napi, struct sk_buff *skb)
3839 struct sk_buff **pp = NULL;
3840 struct packet_offload *ptype;
3841 __be16 type = skb->protocol;
3842 struct list_head *head = &offload_base;
3844 enum gro_result ret;
3846 if (!(skb->dev->features & NETIF_F_GRO) || netpoll_rx_on(skb))
3849 if (skb_is_gso(skb) || skb_has_frag_list(skb))
3852 skb_gro_reset_offset(skb);
3853 gro_list_prepare(napi, skb);
3854 NAPI_GRO_CB(skb)->csum = skb->csum; /* Needed for CHECKSUM_COMPLETE */
3857 list_for_each_entry_rcu(ptype, head, list) {
3858 if (ptype->type != type || !ptype->callbacks.gro_receive)
3861 skb_set_network_header(skb, skb_gro_offset(skb));
3862 skb_reset_mac_len(skb);
3863 NAPI_GRO_CB(skb)->same_flow = 0;
3864 NAPI_GRO_CB(skb)->flush = 0;
3865 NAPI_GRO_CB(skb)->free = 0;
3867 pp = ptype->callbacks.gro_receive(&napi->gro_list, skb);
3872 if (&ptype->list == head)
3875 same_flow = NAPI_GRO_CB(skb)->same_flow;
3876 ret = NAPI_GRO_CB(skb)->free ? GRO_MERGED_FREE : GRO_MERGED;
3879 struct sk_buff *nskb = *pp;
3883 napi_gro_complete(nskb);
3890 if (NAPI_GRO_CB(skb)->flush)
3893 if (unlikely(napi->gro_count >= MAX_GRO_SKBS)) {
3894 struct sk_buff *nskb = napi->gro_list;
3896 /* locate the end of the list to select the 'oldest' flow */
3897 while (nskb->next) {
3903 napi_gro_complete(nskb);
3907 NAPI_GRO_CB(skb)->count = 1;
3908 NAPI_GRO_CB(skb)->age = jiffies;
3909 skb_shinfo(skb)->gso_size = skb_gro_len(skb);
3910 skb->next = napi->gro_list;
3911 napi->gro_list = skb;
3915 if (skb_headlen(skb) < skb_gro_offset(skb)) {
3916 int grow = skb_gro_offset(skb) - skb_headlen(skb);
3918 BUG_ON(skb->end - skb->tail < grow);
3920 memcpy(skb_tail_pointer(skb), NAPI_GRO_CB(skb)->frag0, grow);
3923 skb->data_len -= grow;
3925 skb_shinfo(skb)->frags[0].page_offset += grow;
3926 skb_frag_size_sub(&skb_shinfo(skb)->frags[0], grow);
3928 if (unlikely(!skb_frag_size(&skb_shinfo(skb)->frags[0]))) {
3929 skb_frag_unref(skb, 0);
3930 memmove(skb_shinfo(skb)->frags,
3931 skb_shinfo(skb)->frags + 1,
3932 --skb_shinfo(skb)->nr_frags * sizeof(skb_frag_t));
3944 struct packet_offload *gro_find_receive_by_type(__be16 type)
3946 struct list_head *offload_head = &offload_base;
3947 struct packet_offload *ptype;
3949 list_for_each_entry_rcu(ptype, offload_head, list) {
3950 if (ptype->type != type || !ptype->callbacks.gro_receive)
3957 struct packet_offload *gro_find_complete_by_type(__be16 type)
3959 struct list_head *offload_head = &offload_base;
3960 struct packet_offload *ptype;
3962 list_for_each_entry_rcu(ptype, offload_head, list) {
3963 if (ptype->type != type || !ptype->callbacks.gro_complete)
3970 static gro_result_t napi_skb_finish(gro_result_t ret, struct sk_buff *skb)
3974 if (netif_receive_skb(skb))
3982 case GRO_MERGED_FREE:
3983 if (NAPI_GRO_CB(skb)->free == NAPI_GRO_FREE_STOLEN_HEAD)
3984 kmem_cache_free(skbuff_head_cache, skb);
3997 gro_result_t napi_gro_receive(struct napi_struct *napi, struct sk_buff *skb)
3999 return napi_skb_finish(dev_gro_receive(napi, skb), skb);
4001 EXPORT_SYMBOL(napi_gro_receive);
4003 static void napi_reuse_skb(struct napi_struct *napi, struct sk_buff *skb)
4005 __skb_pull(skb, skb_headlen(skb));
4006 /* restore the reserve we had after netdev_alloc_skb_ip_align() */
4007 skb_reserve(skb, NET_SKB_PAD + NET_IP_ALIGN - skb_headroom(skb));
4009 skb->dev = napi->dev;
4015 struct sk_buff *napi_get_frags(struct napi_struct *napi)
4017 struct sk_buff *skb = napi->skb;
4020 skb = netdev_alloc_skb_ip_align(napi->dev, GRO_MAX_HEAD);
4025 EXPORT_SYMBOL(napi_get_frags);
4027 static gro_result_t napi_frags_finish(struct napi_struct *napi, struct sk_buff *skb,
4032 if (netif_receive_skb(skb))
4037 case GRO_MERGED_FREE:
4038 napi_reuse_skb(napi, skb);
4049 static struct sk_buff *napi_frags_skb(struct napi_struct *napi)
4051 struct sk_buff *skb = napi->skb;
4055 if (unlikely(!pskb_may_pull(skb, sizeof(struct ethhdr)))) {
4056 napi_reuse_skb(napi, skb);
4059 skb->protocol = eth_type_trans(skb, skb->dev);
4064 gro_result_t napi_gro_frags(struct napi_struct *napi)
4066 struct sk_buff *skb = napi_frags_skb(napi);
4071 return napi_frags_finish(napi, skb, dev_gro_receive(napi, skb));
4073 EXPORT_SYMBOL(napi_gro_frags);
4076 * net_rps_action_and_irq_enable sends any pending IPI's for rps.
4077 * Note: called with local irq disabled, but exits with local irq enabled.
4079 static void net_rps_action_and_irq_enable(struct softnet_data *sd)
4082 struct softnet_data *remsd = sd->rps_ipi_list;
4085 sd->rps_ipi_list = NULL;
4089 /* Send pending IPI's to kick RPS processing on remote cpus. */
4091 struct softnet_data *next = remsd->rps_ipi_next;
4093 if (cpu_online(remsd->cpu))
4094 __smp_call_function_single(remsd->cpu,
4103 static int process_backlog(struct napi_struct *napi, int quota)
4106 struct softnet_data *sd = container_of(napi, struct softnet_data, backlog);
4109 /* Check if we have pending ipi, its better to send them now,
4110 * not waiting net_rx_action() end.
4112 if (sd->rps_ipi_list) {
4113 local_irq_disable();
4114 net_rps_action_and_irq_enable(sd);
4117 napi->weight = weight_p;
4118 local_irq_disable();
4119 while (work < quota) {
4120 struct sk_buff *skb;
4123 while ((skb = __skb_dequeue(&sd->process_queue))) {
4125 __netif_receive_skb(skb);
4126 local_irq_disable();
4127 input_queue_head_incr(sd);
4128 if (++work >= quota) {
4135 qlen = skb_queue_len(&sd->input_pkt_queue);
4137 skb_queue_splice_tail_init(&sd->input_pkt_queue,
4138 &sd->process_queue);
4140 if (qlen < quota - work) {
4142 * Inline a custom version of __napi_complete().
4143 * only current cpu owns and manipulates this napi,
4144 * and NAPI_STATE_SCHED is the only possible flag set on backlog.
4145 * we can use a plain write instead of clear_bit(),
4146 * and we dont need an smp_mb() memory barrier.
4148 list_del(&napi->poll_list);
4151 quota = work + qlen;
4161 * __napi_schedule - schedule for receive
4162 * @n: entry to schedule
4164 * The entry's receive function will be scheduled to run
4166 void __napi_schedule(struct napi_struct *n)
4168 unsigned long flags;
4170 local_irq_save(flags);
4171 ____napi_schedule(&__get_cpu_var(softnet_data), n);
4172 local_irq_restore(flags);
4174 EXPORT_SYMBOL(__napi_schedule);
4176 void __napi_complete(struct napi_struct *n)
4178 BUG_ON(!test_bit(NAPI_STATE_SCHED, &n->state));
4179 BUG_ON(n->gro_list);
4181 list_del(&n->poll_list);
4182 smp_mb__before_clear_bit();
4183 clear_bit(NAPI_STATE_SCHED, &n->state);
4185 EXPORT_SYMBOL(__napi_complete);
4187 void napi_complete(struct napi_struct *n)
4189 unsigned long flags;
4192 * don't let napi dequeue from the cpu poll list
4193 * just in case its running on a different cpu
4195 if (unlikely(test_bit(NAPI_STATE_NPSVC, &n->state)))
4198 napi_gro_flush(n, false);
4199 local_irq_save(flags);
4201 local_irq_restore(flags);
4203 EXPORT_SYMBOL(napi_complete);
4205 /* must be called under rcu_read_lock(), as we dont take a reference */
4206 struct napi_struct *napi_by_id(unsigned int napi_id)
4208 unsigned int hash = napi_id % HASH_SIZE(napi_hash);
4209 struct napi_struct *napi;
4211 hlist_for_each_entry_rcu(napi, &napi_hash[hash], napi_hash_node)
4212 if (napi->napi_id == napi_id)
4217 EXPORT_SYMBOL_GPL(napi_by_id);
4219 void napi_hash_add(struct napi_struct *napi)
4221 if (!test_and_set_bit(NAPI_STATE_HASHED, &napi->state)) {
4223 spin_lock(&napi_hash_lock);
4225 /* 0 is not a valid id, we also skip an id that is taken
4226 * we expect both events to be extremely rare
4229 while (!napi->napi_id) {
4230 napi->napi_id = ++napi_gen_id;
4231 if (napi_by_id(napi->napi_id))
4235 hlist_add_head_rcu(&napi->napi_hash_node,
4236 &napi_hash[napi->napi_id % HASH_SIZE(napi_hash)]);
4238 spin_unlock(&napi_hash_lock);
4241 EXPORT_SYMBOL_GPL(napi_hash_add);
4243 /* Warning : caller is responsible to make sure rcu grace period
4244 * is respected before freeing memory containing @napi
4246 void napi_hash_del(struct napi_struct *napi)
4248 spin_lock(&napi_hash_lock);
4250 if (test_and_clear_bit(NAPI_STATE_HASHED, &napi->state))
4251 hlist_del_rcu(&napi->napi_hash_node);
4253 spin_unlock(&napi_hash_lock);
4255 EXPORT_SYMBOL_GPL(napi_hash_del);
4257 void netif_napi_add(struct net_device *dev, struct napi_struct *napi,
4258 int (*poll)(struct napi_struct *, int), int weight)
4260 INIT_LIST_HEAD(&napi->poll_list);
4261 napi->gro_count = 0;
4262 napi->gro_list = NULL;
4265 if (weight > NAPI_POLL_WEIGHT)
4266 pr_err_once("netif_napi_add() called with weight %d on device %s\n",
4268 napi->weight = weight;
4269 list_add(&napi->dev_list, &dev->napi_list);
4271 #ifdef CONFIG_NETPOLL
4272 spin_lock_init(&napi->poll_lock);
4273 napi->poll_owner = -1;
4275 set_bit(NAPI_STATE_SCHED, &napi->state);
4277 EXPORT_SYMBOL(netif_napi_add);
4279 void netif_napi_del(struct napi_struct *napi)
4281 list_del_init(&napi->dev_list);
4282 napi_free_frags(napi);
4284 kfree_skb_list(napi->gro_list);
4285 napi->gro_list = NULL;
4286 napi->gro_count = 0;
4288 EXPORT_SYMBOL(netif_napi_del);
4290 static void net_rx_action(struct softirq_action *h)
4292 struct softnet_data *sd = &__get_cpu_var(softnet_data);
4293 unsigned long time_limit = jiffies + 2;
4294 int budget = netdev_budget;
4297 local_irq_disable();
4299 while (!list_empty(&sd->poll_list)) {
4300 struct napi_struct *n;
4303 /* If softirq window is exhuasted then punt.
4304 * Allow this to run for 2 jiffies since which will allow
4305 * an average latency of 1.5/HZ.
4307 if (unlikely(budget <= 0 || time_after_eq(jiffies, time_limit)))
4312 /* Even though interrupts have been re-enabled, this
4313 * access is safe because interrupts can only add new
4314 * entries to the tail of this list, and only ->poll()
4315 * calls can remove this head entry from the list.
4317 n = list_first_entry(&sd->poll_list, struct napi_struct, poll_list);
4319 have = netpoll_poll_lock(n);
4323 /* This NAPI_STATE_SCHED test is for avoiding a race
4324 * with netpoll's poll_napi(). Only the entity which
4325 * obtains the lock and sees NAPI_STATE_SCHED set will
4326 * actually make the ->poll() call. Therefore we avoid
4327 * accidentally calling ->poll() when NAPI is not scheduled.
4330 if (test_bit(NAPI_STATE_SCHED, &n->state)) {
4331 work = n->poll(n, weight);
4335 WARN_ON_ONCE(work > weight);
4339 local_irq_disable();
4341 /* Drivers must not modify the NAPI state if they
4342 * consume the entire weight. In such cases this code
4343 * still "owns" the NAPI instance and therefore can
4344 * move the instance around on the list at-will.
4346 if (unlikely(work == weight)) {
4347 if (unlikely(napi_disable_pending(n))) {
4350 local_irq_disable();
4353 /* flush too old packets
4354 * If HZ < 1000, flush all packets.
4357 napi_gro_flush(n, HZ >= 1000);
4358 local_irq_disable();
4360 list_move_tail(&n->poll_list, &sd->poll_list);
4364 netpoll_poll_unlock(have);
4367 net_rps_action_and_irq_enable(sd);
4369 #ifdef CONFIG_NET_DMA
4371 * There may not be any more sk_buffs coming right now, so push
4372 * any pending DMA copies to hardware
4374 dma_issue_pending_all();
4381 __raise_softirq_irqoff(NET_RX_SOFTIRQ);
4385 struct netdev_adjacent {
4386 struct net_device *dev;
4388 /* upper master flag, there can only be one master device per list */
4391 /* counter for the number of times this device was added to us */
4394 /* private field for the users */
4397 struct list_head list;
4398 struct rcu_head rcu;
4401 static struct netdev_adjacent *__netdev_find_adj(struct net_device *dev,
4402 struct net_device *adj_dev,
4403 struct list_head *adj_list)
4405 struct netdev_adjacent *adj;
4407 list_for_each_entry(adj, adj_list, list) {
4408 if (adj->dev == adj_dev)
4415 * netdev_has_upper_dev - Check if device is linked to an upper device
4417 * @upper_dev: upper device to check
4419 * Find out if a device is linked to specified upper device and return true
4420 * in case it is. Note that this checks only immediate upper device,
4421 * not through a complete stack of devices. The caller must hold the RTNL lock.
4423 bool netdev_has_upper_dev(struct net_device *dev,
4424 struct net_device *upper_dev)
4428 return __netdev_find_adj(dev, upper_dev, &dev->all_adj_list.upper);
4430 EXPORT_SYMBOL(netdev_has_upper_dev);
4433 * netdev_has_any_upper_dev - Check if device is linked to some device
4436 * Find out if a device is linked to an upper device and return true in case
4437 * it is. The caller must hold the RTNL lock.
4439 static bool netdev_has_any_upper_dev(struct net_device *dev)
4443 return !list_empty(&dev->all_adj_list.upper);
4447 * netdev_master_upper_dev_get - Get master upper device
4450 * Find a master upper device and return pointer to it or NULL in case
4451 * it's not there. The caller must hold the RTNL lock.
4453 struct net_device *netdev_master_upper_dev_get(struct net_device *dev)
4455 struct netdev_adjacent *upper;
4459 if (list_empty(&dev->adj_list.upper))
4462 upper = list_first_entry(&dev->adj_list.upper,
4463 struct netdev_adjacent, list);
4464 if (likely(upper->master))
4468 EXPORT_SYMBOL(netdev_master_upper_dev_get);
4470 void *netdev_adjacent_get_private(struct list_head *adj_list)
4472 struct netdev_adjacent *adj;
4474 adj = list_entry(adj_list, struct netdev_adjacent, list);
4476 return adj->private;
4478 EXPORT_SYMBOL(netdev_adjacent_get_private);
4481 * netdev_all_upper_get_next_dev_rcu - Get the next dev from upper list
4483 * @iter: list_head ** of the current position
4485 * Gets the next device from the dev's upper list, starting from iter
4486 * position. The caller must hold RCU read lock.
4488 struct net_device *netdev_all_upper_get_next_dev_rcu(struct net_device *dev,
4489 struct list_head **iter)
4491 struct netdev_adjacent *upper;
4493 WARN_ON_ONCE(!rcu_read_lock_held() && !lockdep_rtnl_is_held());
4495 upper = list_entry_rcu((*iter)->next, struct netdev_adjacent, list);
4497 if (&upper->list == &dev->all_adj_list.upper)
4500 *iter = &upper->list;
4504 EXPORT_SYMBOL(netdev_all_upper_get_next_dev_rcu);
4507 * netdev_lower_get_next_private - Get the next ->private from the
4508 * lower neighbour list
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 either hold the
4514 * RTNL lock or its own locking that guarantees that the neighbour lower
4515 * list will remain unchainged.
4517 void *netdev_lower_get_next_private(struct net_device *dev,
4518 struct list_head **iter)
4520 struct netdev_adjacent *lower;
4522 lower = list_entry(*iter, struct netdev_adjacent, list);
4524 if (&lower->list == &dev->adj_list.lower)
4528 *iter = lower->list.next;
4530 return lower->private;
4532 EXPORT_SYMBOL(netdev_lower_get_next_private);
4535 * netdev_lower_get_next_private_rcu - Get the next ->private from the
4536 * lower neighbour list, RCU
4539 * @iter: list_head ** of the current position
4541 * Gets the next netdev_adjacent->private from the dev's lower neighbour
4542 * list, starting from iter position. The caller must hold RCU read lock.
4544 void *netdev_lower_get_next_private_rcu(struct net_device *dev,
4545 struct list_head **iter)
4547 struct netdev_adjacent *lower;
4549 WARN_ON_ONCE(!rcu_read_lock_held());
4551 lower = list_entry_rcu((*iter)->next, struct netdev_adjacent, list);
4553 if (&lower->list == &dev->adj_list.lower)
4557 *iter = &lower->list;
4559 return lower->private;
4561 EXPORT_SYMBOL(netdev_lower_get_next_private_rcu);
4564 * netdev_lower_get_first_private_rcu - Get the first ->private from the
4565 * lower neighbour list, RCU
4569 * Gets the first netdev_adjacent->private from the dev's lower neighbour
4570 * list. The caller must hold RCU read lock.
4572 void *netdev_lower_get_first_private_rcu(struct net_device *dev)
4574 struct netdev_adjacent *lower;
4576 lower = list_first_or_null_rcu(&dev->adj_list.lower,
4577 struct netdev_adjacent, list);
4579 return lower->private;
4582 EXPORT_SYMBOL(netdev_lower_get_first_private_rcu);
4585 * netdev_master_upper_dev_get_rcu - Get master upper device
4588 * Find a master upper device and return pointer to it or NULL in case
4589 * it's not there. The caller must hold the RCU read lock.
4591 struct net_device *netdev_master_upper_dev_get_rcu(struct net_device *dev)
4593 struct netdev_adjacent *upper;
4595 upper = list_first_or_null_rcu(&dev->adj_list.upper,
4596 struct netdev_adjacent, list);
4597 if (upper && likely(upper->master))
4601 EXPORT_SYMBOL(netdev_master_upper_dev_get_rcu);
4603 static int __netdev_adjacent_dev_insert(struct net_device *dev,
4604 struct net_device *adj_dev,
4605 struct list_head *dev_list,
4606 void *private, bool master)
4608 struct netdev_adjacent *adj;
4609 char linkname[IFNAMSIZ+7];
4612 adj = __netdev_find_adj(dev, adj_dev, dev_list);
4619 adj = kmalloc(sizeof(*adj), GFP_KERNEL);
4624 adj->master = master;
4626 adj->private = private;
4629 pr_debug("dev_hold for %s, because of link added from %s to %s\n",
4630 adj_dev->name, dev->name, adj_dev->name);
4632 if (dev_list == &dev->adj_list.lower) {
4633 sprintf(linkname, "lower_%s", adj_dev->name);
4634 ret = sysfs_create_link(&(dev->dev.kobj),
4635 &(adj_dev->dev.kobj), linkname);
4638 } else if (dev_list == &dev->adj_list.upper) {
4639 sprintf(linkname, "upper_%s", adj_dev->name);
4640 ret = sysfs_create_link(&(dev->dev.kobj),
4641 &(adj_dev->dev.kobj), linkname);
4646 /* Ensure that master link is always the first item in list. */
4648 ret = sysfs_create_link(&(dev->dev.kobj),
4649 &(adj_dev->dev.kobj), "master");
4651 goto remove_symlinks;
4653 list_add_rcu(&adj->list, dev_list);
4655 list_add_tail_rcu(&adj->list, dev_list);
4661 if (dev_list == &dev->adj_list.lower) {
4662 sprintf(linkname, "lower_%s", adj_dev->name);
4663 sysfs_remove_link(&(dev->dev.kobj), linkname);
4664 } else if (dev_list == &dev->adj_list.upper) {
4665 sprintf(linkname, "upper_%s", adj_dev->name);
4666 sysfs_remove_link(&(dev->dev.kobj), linkname);
4676 static void __netdev_adjacent_dev_remove(struct net_device *dev,
4677 struct net_device *adj_dev,
4678 struct list_head *dev_list)
4680 struct netdev_adjacent *adj;
4681 char linkname[IFNAMSIZ+7];
4683 adj = __netdev_find_adj(dev, adj_dev, dev_list);
4686 pr_err("tried to remove device %s from %s\n",
4687 dev->name, adj_dev->name);
4691 if (adj->ref_nr > 1) {
4692 pr_debug("%s to %s ref_nr-- = %d\n", dev->name, adj_dev->name,
4699 sysfs_remove_link(&(dev->dev.kobj), "master");
4701 if (dev_list == &dev->adj_list.lower) {
4702 sprintf(linkname, "lower_%s", adj_dev->name);
4703 sysfs_remove_link(&(dev->dev.kobj), linkname);
4704 } else if (dev_list == &dev->adj_list.upper) {
4705 sprintf(linkname, "upper_%s", adj_dev->name);
4706 sysfs_remove_link(&(dev->dev.kobj), linkname);
4709 list_del_rcu(&adj->list);
4710 pr_debug("dev_put for %s, because link removed from %s to %s\n",
4711 adj_dev->name, dev->name, adj_dev->name);
4713 kfree_rcu(adj, rcu);
4716 static int __netdev_adjacent_dev_link_lists(struct net_device *dev,
4717 struct net_device *upper_dev,
4718 struct list_head *up_list,
4719 struct list_head *down_list,
4720 void *private, bool master)
4724 ret = __netdev_adjacent_dev_insert(dev, upper_dev, up_list, private,
4729 ret = __netdev_adjacent_dev_insert(upper_dev, dev, down_list, private,
4732 __netdev_adjacent_dev_remove(dev, upper_dev, up_list);
4739 static int __netdev_adjacent_dev_link(struct net_device *dev,
4740 struct net_device *upper_dev)
4742 return __netdev_adjacent_dev_link_lists(dev, upper_dev,
4743 &dev->all_adj_list.upper,
4744 &upper_dev->all_adj_list.lower,
4748 static void __netdev_adjacent_dev_unlink_lists(struct net_device *dev,
4749 struct net_device *upper_dev,
4750 struct list_head *up_list,
4751 struct list_head *down_list)
4753 __netdev_adjacent_dev_remove(dev, upper_dev, up_list);
4754 __netdev_adjacent_dev_remove(upper_dev, dev, down_list);
4757 static void __netdev_adjacent_dev_unlink(struct net_device *dev,
4758 struct net_device *upper_dev)
4760 __netdev_adjacent_dev_unlink_lists(dev, upper_dev,
4761 &dev->all_adj_list.upper,
4762 &upper_dev->all_adj_list.lower);
4765 static int __netdev_adjacent_dev_link_neighbour(struct net_device *dev,
4766 struct net_device *upper_dev,
4767 void *private, bool master)
4769 int ret = __netdev_adjacent_dev_link(dev, upper_dev);
4774 ret = __netdev_adjacent_dev_link_lists(dev, upper_dev,
4775 &dev->adj_list.upper,
4776 &upper_dev->adj_list.lower,
4779 __netdev_adjacent_dev_unlink(dev, upper_dev);
4786 static void __netdev_adjacent_dev_unlink_neighbour(struct net_device *dev,
4787 struct net_device *upper_dev)
4789 __netdev_adjacent_dev_unlink(dev, upper_dev);
4790 __netdev_adjacent_dev_unlink_lists(dev, upper_dev,
4791 &dev->adj_list.upper,
4792 &upper_dev->adj_list.lower);
4795 static int __netdev_upper_dev_link(struct net_device *dev,
4796 struct net_device *upper_dev, bool master,
4799 struct netdev_adjacent *i, *j, *to_i, *to_j;
4804 if (dev == upper_dev)
4807 /* To prevent loops, check if dev is not upper device to upper_dev. */
4808 if (__netdev_find_adj(upper_dev, dev, &upper_dev->all_adj_list.upper))
4811 if (__netdev_find_adj(dev, upper_dev, &dev->all_adj_list.upper))
4814 if (master && netdev_master_upper_dev_get(dev))
4817 ret = __netdev_adjacent_dev_link_neighbour(dev, upper_dev, private,
4822 /* Now that we linked these devs, make all the upper_dev's
4823 * all_adj_list.upper visible to every dev's all_adj_list.lower an
4824 * versa, and don't forget the devices itself. All of these
4825 * links are non-neighbours.
4827 list_for_each_entry(i, &dev->all_adj_list.lower, list) {
4828 list_for_each_entry(j, &upper_dev->all_adj_list.upper, list) {
4829 pr_debug("Interlinking %s with %s, non-neighbour\n",
4830 i->dev->name, j->dev->name);
4831 ret = __netdev_adjacent_dev_link(i->dev, j->dev);
4837 /* add dev to every upper_dev's upper device */
4838 list_for_each_entry(i, &upper_dev->all_adj_list.upper, list) {
4839 pr_debug("linking %s's upper device %s with %s\n",
4840 upper_dev->name, i->dev->name, dev->name);
4841 ret = __netdev_adjacent_dev_link(dev, i->dev);
4843 goto rollback_upper_mesh;
4846 /* add upper_dev to every dev's lower device */
4847 list_for_each_entry(i, &dev->all_adj_list.lower, list) {
4848 pr_debug("linking %s's lower device %s with %s\n", dev->name,
4849 i->dev->name, upper_dev->name);
4850 ret = __netdev_adjacent_dev_link(i->dev, upper_dev);
4852 goto rollback_lower_mesh;
4855 call_netdevice_notifiers(NETDEV_CHANGEUPPER, dev);
4858 rollback_lower_mesh:
4860 list_for_each_entry(i, &dev->all_adj_list.lower, list) {
4863 __netdev_adjacent_dev_unlink(i->dev, upper_dev);
4868 rollback_upper_mesh:
4870 list_for_each_entry(i, &upper_dev->all_adj_list.upper, list) {
4873 __netdev_adjacent_dev_unlink(dev, i->dev);
4881 list_for_each_entry(i, &dev->all_adj_list.lower, list) {
4882 list_for_each_entry(j, &upper_dev->all_adj_list.upper, list) {
4883 if (i == to_i && j == to_j)
4885 __netdev_adjacent_dev_unlink(i->dev, j->dev);
4891 __netdev_adjacent_dev_unlink_neighbour(dev, upper_dev);
4897 * netdev_upper_dev_link - Add a link to the upper device
4899 * @upper_dev: new upper device
4901 * Adds a link to device which is upper to this one. The caller must hold
4902 * the RTNL lock. On a failure a negative errno code is returned.
4903 * On success the reference counts are adjusted and the function
4906 int netdev_upper_dev_link(struct net_device *dev,
4907 struct net_device *upper_dev)
4909 return __netdev_upper_dev_link(dev, upper_dev, false, NULL);
4911 EXPORT_SYMBOL(netdev_upper_dev_link);
4914 * netdev_master_upper_dev_link - Add a master link to the upper device
4916 * @upper_dev: new upper device
4918 * Adds a link to device which is upper to this one. In this case, only
4919 * one master upper device can be linked, although other non-master devices
4920 * might be linked as well. The caller must hold the RTNL lock.
4921 * On a failure a negative errno code is returned. On success the reference
4922 * counts are adjusted and the function returns zero.
4924 int netdev_master_upper_dev_link(struct net_device *dev,
4925 struct net_device *upper_dev)
4927 return __netdev_upper_dev_link(dev, upper_dev, true, NULL);
4929 EXPORT_SYMBOL(netdev_master_upper_dev_link);
4931 int netdev_master_upper_dev_link_private(struct net_device *dev,
4932 struct net_device *upper_dev,
4935 return __netdev_upper_dev_link(dev, upper_dev, true, private);
4937 EXPORT_SYMBOL(netdev_master_upper_dev_link_private);
4940 * netdev_upper_dev_unlink - Removes a link to upper device
4942 * @upper_dev: new upper device
4944 * Removes a link to device which is upper to this one. The caller must hold
4947 void netdev_upper_dev_unlink(struct net_device *dev,
4948 struct net_device *upper_dev)
4950 struct netdev_adjacent *i, *j;
4953 __netdev_adjacent_dev_unlink_neighbour(dev, upper_dev);
4955 /* Here is the tricky part. We must remove all dev's lower
4956 * devices from all upper_dev's upper devices and vice
4957 * versa, to maintain the graph relationship.
4959 list_for_each_entry(i, &dev->all_adj_list.lower, list)
4960 list_for_each_entry(j, &upper_dev->all_adj_list.upper, list)
4961 __netdev_adjacent_dev_unlink(i->dev, j->dev);
4963 /* remove also the devices itself from lower/upper device
4966 list_for_each_entry(i, &dev->all_adj_list.lower, list)
4967 __netdev_adjacent_dev_unlink(i->dev, upper_dev);
4969 list_for_each_entry(i, &upper_dev->all_adj_list.upper, list)
4970 __netdev_adjacent_dev_unlink(dev, i->dev);
4972 call_netdevice_notifiers(NETDEV_CHANGEUPPER, dev);
4974 EXPORT_SYMBOL(netdev_upper_dev_unlink);
4976 void *netdev_lower_dev_get_private(struct net_device *dev,
4977 struct net_device *lower_dev)
4979 struct netdev_adjacent *lower;
4983 lower = __netdev_find_adj(dev, lower_dev, &dev->adj_list.lower);
4987 return lower->private;
4989 EXPORT_SYMBOL(netdev_lower_dev_get_private);
4991 static void dev_change_rx_flags(struct net_device *dev, int flags)
4993 const struct net_device_ops *ops = dev->netdev_ops;
4995 if (ops->ndo_change_rx_flags)
4996 ops->ndo_change_rx_flags(dev, flags);
4999 static int __dev_set_promiscuity(struct net_device *dev, int inc, bool notify)
5001 unsigned int old_flags = dev->flags;
5007 dev->flags |= IFF_PROMISC;
5008 dev->promiscuity += inc;
5009 if (dev->promiscuity == 0) {
5012 * If inc causes overflow, untouch promisc and return error.
5015 dev->flags &= ~IFF_PROMISC;
5017 dev->promiscuity -= inc;
5018 pr_warn("%s: promiscuity touches roof, set promiscuity failed. promiscuity feature of device might be broken.\n",
5023 if (dev->flags != old_flags) {
5024 pr_info("device %s %s promiscuous mode\n",
5026 dev->flags & IFF_PROMISC ? "entered" : "left");
5027 if (audit_enabled) {
5028 current_uid_gid(&uid, &gid);
5029 audit_log(current->audit_context, GFP_ATOMIC,
5030 AUDIT_ANOM_PROMISCUOUS,
5031 "dev=%s prom=%d old_prom=%d auid=%u uid=%u gid=%u ses=%u",
5032 dev->name, (dev->flags & IFF_PROMISC),
5033 (old_flags & IFF_PROMISC),
5034 from_kuid(&init_user_ns, audit_get_loginuid(current)),
5035 from_kuid(&init_user_ns, uid),
5036 from_kgid(&init_user_ns, gid),
5037 audit_get_sessionid(current));
5040 dev_change_rx_flags(dev, IFF_PROMISC);
5043 __dev_notify_flags(dev, old_flags, IFF_PROMISC);
5048 * dev_set_promiscuity - update promiscuity count on a device
5052 * Add or remove promiscuity from a device. While the count in the device
5053 * remains above zero the interface remains promiscuous. Once it hits zero
5054 * the device reverts back to normal filtering operation. A negative inc
5055 * value is used to drop promiscuity on the device.
5056 * Return 0 if successful or a negative errno code on error.
5058 int dev_set_promiscuity(struct net_device *dev, int inc)
5060 unsigned int old_flags = dev->flags;
5063 err = __dev_set_promiscuity(dev, inc, true);
5066 if (dev->flags != old_flags)
5067 dev_set_rx_mode(dev);
5070 EXPORT_SYMBOL(dev_set_promiscuity);
5072 static int __dev_set_allmulti(struct net_device *dev, int inc, bool notify)
5074 unsigned int old_flags = dev->flags, old_gflags = dev->gflags;
5078 dev->flags |= IFF_ALLMULTI;
5079 dev->allmulti += inc;
5080 if (dev->allmulti == 0) {
5083 * If inc causes overflow, untouch allmulti and return error.
5086 dev->flags &= ~IFF_ALLMULTI;
5088 dev->allmulti -= inc;
5089 pr_warn("%s: allmulti touches roof, set allmulti failed. allmulti feature of device might be broken.\n",
5094 if (dev->flags ^ old_flags) {
5095 dev_change_rx_flags(dev, IFF_ALLMULTI);
5096 dev_set_rx_mode(dev);
5098 __dev_notify_flags(dev, old_flags,
5099 dev->gflags ^ old_gflags);
5105 * dev_set_allmulti - update allmulti count on a device
5109 * Add or remove reception of all multicast frames to a device. While the
5110 * count in the device remains above zero the interface remains listening
5111 * to all interfaces. Once it hits zero the device reverts back to normal
5112 * filtering operation. A negative @inc value is used to drop the counter
5113 * when releasing a resource needing all multicasts.
5114 * Return 0 if successful or a negative errno code on error.
5117 int dev_set_allmulti(struct net_device *dev, int inc)
5119 return __dev_set_allmulti(dev, inc, true);
5121 EXPORT_SYMBOL(dev_set_allmulti);
5124 * Upload unicast and multicast address lists to device and
5125 * configure RX filtering. When the device doesn't support unicast
5126 * filtering it is put in promiscuous mode while unicast addresses
5129 void __dev_set_rx_mode(struct net_device *dev)
5131 const struct net_device_ops *ops = dev->netdev_ops;
5133 /* dev_open will call this function so the list will stay sane. */
5134 if (!(dev->flags&IFF_UP))
5137 if (!netif_device_present(dev))
5140 if (!(dev->priv_flags & IFF_UNICAST_FLT)) {
5141 /* Unicast addresses changes may only happen under the rtnl,
5142 * therefore calling __dev_set_promiscuity here is safe.
5144 if (!netdev_uc_empty(dev) && !dev->uc_promisc) {
5145 __dev_set_promiscuity(dev, 1, false);
5146 dev->uc_promisc = true;
5147 } else if (netdev_uc_empty(dev) && dev->uc_promisc) {
5148 __dev_set_promiscuity(dev, -1, false);
5149 dev->uc_promisc = false;
5153 if (ops->ndo_set_rx_mode)
5154 ops->ndo_set_rx_mode(dev);
5157 void dev_set_rx_mode(struct net_device *dev)
5159 netif_addr_lock_bh(dev);
5160 __dev_set_rx_mode(dev);
5161 netif_addr_unlock_bh(dev);
5165 * dev_get_flags - get flags reported to userspace
5168 * Get the combination of flag bits exported through APIs to userspace.
5170 unsigned int dev_get_flags(const struct net_device *dev)
5174 flags = (dev->flags & ~(IFF_PROMISC |
5179 (dev->gflags & (IFF_PROMISC |
5182 if (netif_running(dev)) {
5183 if (netif_oper_up(dev))
5184 flags |= IFF_RUNNING;
5185 if (netif_carrier_ok(dev))
5186 flags |= IFF_LOWER_UP;
5187 if (netif_dormant(dev))
5188 flags |= IFF_DORMANT;
5193 EXPORT_SYMBOL(dev_get_flags);
5195 int __dev_change_flags(struct net_device *dev, unsigned int flags)
5197 unsigned int old_flags = dev->flags;
5203 * Set the flags on our device.
5206 dev->flags = (flags & (IFF_DEBUG | IFF_NOTRAILERS | IFF_NOARP |
5207 IFF_DYNAMIC | IFF_MULTICAST | IFF_PORTSEL |
5209 (dev->flags & (IFF_UP | IFF_VOLATILE | IFF_PROMISC |
5213 * Load in the correct multicast list now the flags have changed.
5216 if ((old_flags ^ flags) & IFF_MULTICAST)
5217 dev_change_rx_flags(dev, IFF_MULTICAST);
5219 dev_set_rx_mode(dev);
5222 * Have we downed the interface. We handle IFF_UP ourselves
5223 * according to user attempts to set it, rather than blindly
5228 if ((old_flags ^ flags) & IFF_UP) { /* Bit is different ? */
5229 ret = ((old_flags & IFF_UP) ? __dev_close : __dev_open)(dev);
5232 dev_set_rx_mode(dev);
5235 if ((flags ^ dev->gflags) & IFF_PROMISC) {
5236 int inc = (flags & IFF_PROMISC) ? 1 : -1;
5237 unsigned int old_flags = dev->flags;
5239 dev->gflags ^= IFF_PROMISC;
5241 if (__dev_set_promiscuity(dev, inc, false) >= 0)
5242 if (dev->flags != old_flags)
5243 dev_set_rx_mode(dev);
5246 /* NOTE: order of synchronization of IFF_PROMISC and IFF_ALLMULTI
5247 is important. Some (broken) drivers set IFF_PROMISC, when
5248 IFF_ALLMULTI is requested not asking us and not reporting.
5250 if ((flags ^ dev->gflags) & IFF_ALLMULTI) {
5251 int inc = (flags & IFF_ALLMULTI) ? 1 : -1;
5253 dev->gflags ^= IFF_ALLMULTI;
5254 __dev_set_allmulti(dev, inc, false);
5260 void __dev_notify_flags(struct net_device *dev, unsigned int old_flags,
5261 unsigned int gchanges)
5263 unsigned int changes = dev->flags ^ old_flags;
5266 rtmsg_ifinfo(RTM_NEWLINK, dev, gchanges, GFP_ATOMIC);
5268 if (changes & IFF_UP) {
5269 if (dev->flags & IFF_UP)
5270 call_netdevice_notifiers(NETDEV_UP, dev);
5272 call_netdevice_notifiers(NETDEV_DOWN, dev);
5275 if (dev->flags & IFF_UP &&
5276 (changes & ~(IFF_UP | IFF_PROMISC | IFF_ALLMULTI | IFF_VOLATILE))) {
5277 struct netdev_notifier_change_info change_info;
5279 change_info.flags_changed = changes;
5280 call_netdevice_notifiers_info(NETDEV_CHANGE, dev,
5286 * dev_change_flags - change device settings
5288 * @flags: device state flags
5290 * Change settings on device based state flags. The flags are
5291 * in the userspace exported format.
5293 int dev_change_flags(struct net_device *dev, unsigned int flags)
5296 unsigned int changes, old_flags = dev->flags, old_gflags = dev->gflags;
5298 ret = __dev_change_flags(dev, flags);
5302 changes = (old_flags ^ dev->flags) | (old_gflags ^ dev->gflags);
5303 __dev_notify_flags(dev, old_flags, changes);
5306 EXPORT_SYMBOL(dev_change_flags);
5308 static int __dev_set_mtu(struct net_device *dev, int new_mtu)
5310 const struct net_device_ops *ops = dev->netdev_ops;
5312 if (ops->ndo_change_mtu)
5313 return ops->ndo_change_mtu(dev, new_mtu);
5320 * dev_set_mtu - Change maximum transfer unit
5322 * @new_mtu: new transfer unit
5324 * Change the maximum transfer size of the network device.
5326 int dev_set_mtu(struct net_device *dev, int new_mtu)
5330 if (new_mtu == dev->mtu)
5333 /* MTU must be positive. */
5337 if (!netif_device_present(dev))
5340 orig_mtu = dev->mtu;
5341 err = __dev_set_mtu(dev, new_mtu);
5344 err = call_netdevice_notifiers(NETDEV_CHANGEMTU, dev);
5345 err = notifier_to_errno(err);
5347 /* setting mtu back and notifying everyone again,
5348 * so that they have a chance to revert changes.
5350 __dev_set_mtu(dev, orig_mtu);
5351 call_netdevice_notifiers(NETDEV_CHANGEMTU, dev);
5356 EXPORT_SYMBOL(dev_set_mtu);
5359 * dev_set_group - Change group this device belongs to
5361 * @new_group: group this device should belong to
5363 void dev_set_group(struct net_device *dev, int new_group)
5365 dev->group = new_group;
5367 EXPORT_SYMBOL(dev_set_group);
5370 * dev_set_mac_address - Change Media Access Control Address
5374 * Change the hardware (MAC) address of the device
5376 int dev_set_mac_address(struct net_device *dev, struct sockaddr *sa)
5378 const struct net_device_ops *ops = dev->netdev_ops;
5381 if (!ops->ndo_set_mac_address)
5383 if (sa->sa_family != dev->type)
5385 if (!netif_device_present(dev))
5387 err = ops->ndo_set_mac_address(dev, sa);
5390 dev->addr_assign_type = NET_ADDR_SET;
5391 call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
5392 add_device_randomness(dev->dev_addr, dev->addr_len);
5395 EXPORT_SYMBOL(dev_set_mac_address);
5398 * dev_change_carrier - Change device carrier
5400 * @new_carrier: new value
5402 * Change device carrier
5404 int dev_change_carrier(struct net_device *dev, bool new_carrier)
5406 const struct net_device_ops *ops = dev->netdev_ops;
5408 if (!ops->ndo_change_carrier)
5410 if (!netif_device_present(dev))
5412 return ops->ndo_change_carrier(dev, new_carrier);
5414 EXPORT_SYMBOL(dev_change_carrier);
5417 * dev_get_phys_port_id - Get device physical port ID
5421 * Get device physical port ID
5423 int dev_get_phys_port_id(struct net_device *dev,
5424 struct netdev_phys_port_id *ppid)
5426 const struct net_device_ops *ops = dev->netdev_ops;
5428 if (!ops->ndo_get_phys_port_id)
5430 return ops->ndo_get_phys_port_id(dev, ppid);
5432 EXPORT_SYMBOL(dev_get_phys_port_id);
5435 * dev_new_index - allocate an ifindex
5436 * @net: the applicable net namespace
5438 * Returns a suitable unique value for a new device interface
5439 * number. The caller must hold the rtnl semaphore or the
5440 * dev_base_lock to be sure it remains unique.
5442 static int dev_new_index(struct net *net)
5444 int ifindex = net->ifindex;
5448 if (!__dev_get_by_index(net, ifindex))
5449 return net->ifindex = ifindex;
5453 /* Delayed registration/unregisteration */
5454 static LIST_HEAD(net_todo_list);
5455 static DECLARE_WAIT_QUEUE_HEAD(netdev_unregistering_wq);
5457 static void net_set_todo(struct net_device *dev)
5459 list_add_tail(&dev->todo_list, &net_todo_list);
5460 dev_net(dev)->dev_unreg_count++;
5463 static void rollback_registered_many(struct list_head *head)
5465 struct net_device *dev, *tmp;
5466 LIST_HEAD(close_head);
5468 BUG_ON(dev_boot_phase);
5471 list_for_each_entry_safe(dev, tmp, head, unreg_list) {
5472 /* Some devices call without registering
5473 * for initialization unwind. Remove those
5474 * devices and proceed with the remaining.
5476 if (dev->reg_state == NETREG_UNINITIALIZED) {
5477 pr_debug("unregister_netdevice: device %s/%p never was registered\n",
5481 list_del(&dev->unreg_list);
5484 dev->dismantle = true;
5485 BUG_ON(dev->reg_state != NETREG_REGISTERED);
5488 /* If device is running, close it first. */
5489 list_for_each_entry(dev, head, unreg_list)
5490 list_add_tail(&dev->close_list, &close_head);
5491 dev_close_many(&close_head);
5493 list_for_each_entry(dev, head, unreg_list) {
5494 /* And unlink it from device chain. */
5495 unlist_netdevice(dev);
5497 dev->reg_state = NETREG_UNREGISTERING;
5502 list_for_each_entry(dev, head, unreg_list) {
5503 /* Shutdown queueing discipline. */
5507 /* Notify protocols, that we are about to destroy
5508 this device. They should clean all the things.
5510 call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
5512 if (!dev->rtnl_link_ops ||
5513 dev->rtnl_link_state == RTNL_LINK_INITIALIZED)
5514 rtmsg_ifinfo(RTM_DELLINK, dev, ~0U, GFP_KERNEL);
5517 * Flush the unicast and multicast chains
5522 if (dev->netdev_ops->ndo_uninit)
5523 dev->netdev_ops->ndo_uninit(dev);
5525 /* Notifier chain MUST detach us all upper devices. */
5526 WARN_ON(netdev_has_any_upper_dev(dev));
5528 /* Remove entries from kobject tree */
5529 netdev_unregister_kobject(dev);
5531 /* Remove XPS queueing entries */
5532 netif_reset_xps_queues_gt(dev, 0);
5538 list_for_each_entry(dev, head, unreg_list)
5542 static void rollback_registered(struct net_device *dev)
5546 list_add(&dev->unreg_list, &single);
5547 rollback_registered_many(&single);
5551 static netdev_features_t netdev_fix_features(struct net_device *dev,
5552 netdev_features_t features)
5554 /* Fix illegal checksum combinations */
5555 if ((features & NETIF_F_HW_CSUM) &&
5556 (features & (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))) {
5557 netdev_warn(dev, "mixed HW and IP checksum settings.\n");
5558 features &= ~(NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM);
5561 /* TSO requires that SG is present as well. */
5562 if ((features & NETIF_F_ALL_TSO) && !(features & NETIF_F_SG)) {
5563 netdev_dbg(dev, "Dropping TSO features since no SG feature.\n");
5564 features &= ~NETIF_F_ALL_TSO;
5567 if ((features & NETIF_F_TSO) && !(features & NETIF_F_HW_CSUM) &&
5568 !(features & NETIF_F_IP_CSUM)) {
5569 netdev_dbg(dev, "Dropping TSO features since no CSUM feature.\n");
5570 features &= ~NETIF_F_TSO;
5571 features &= ~NETIF_F_TSO_ECN;
5574 if ((features & NETIF_F_TSO6) && !(features & NETIF_F_HW_CSUM) &&
5575 !(features & NETIF_F_IPV6_CSUM)) {
5576 netdev_dbg(dev, "Dropping TSO6 features since no CSUM feature.\n");
5577 features &= ~NETIF_F_TSO6;
5580 /* TSO ECN requires that TSO is present as well. */
5581 if ((features & NETIF_F_ALL_TSO) == NETIF_F_TSO_ECN)
5582 features &= ~NETIF_F_TSO_ECN;
5584 /* Software GSO depends on SG. */
5585 if ((features & NETIF_F_GSO) && !(features & NETIF_F_SG)) {
5586 netdev_dbg(dev, "Dropping NETIF_F_GSO since no SG feature.\n");
5587 features &= ~NETIF_F_GSO;
5590 /* UFO needs SG and checksumming */
5591 if (features & NETIF_F_UFO) {
5592 /* maybe split UFO into V4 and V6? */
5593 if (!((features & NETIF_F_GEN_CSUM) ||
5594 (features & (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))
5595 == (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))) {
5597 "Dropping NETIF_F_UFO since no checksum offload features.\n");
5598 features &= ~NETIF_F_UFO;
5601 if (!(features & NETIF_F_SG)) {
5603 "Dropping NETIF_F_UFO since no NETIF_F_SG feature.\n");
5604 features &= ~NETIF_F_UFO;
5611 int __netdev_update_features(struct net_device *dev)
5613 netdev_features_t features;
5618 features = netdev_get_wanted_features(dev);
5620 if (dev->netdev_ops->ndo_fix_features)
5621 features = dev->netdev_ops->ndo_fix_features(dev, features);
5623 /* driver might be less strict about feature dependencies */
5624 features = netdev_fix_features(dev, features);
5626 if (dev->features == features)
5629 netdev_dbg(dev, "Features changed: %pNF -> %pNF\n",
5630 &dev->features, &features);
5632 if (dev->netdev_ops->ndo_set_features)
5633 err = dev->netdev_ops->ndo_set_features(dev, features);
5635 if (unlikely(err < 0)) {
5637 "set_features() failed (%d); wanted %pNF, left %pNF\n",
5638 err, &features, &dev->features);
5643 dev->features = features;
5649 * netdev_update_features - recalculate device features
5650 * @dev: the device to check
5652 * Recalculate dev->features set and send notifications if it
5653 * has changed. Should be called after driver or hardware dependent
5654 * conditions might have changed that influence the features.
5656 void netdev_update_features(struct net_device *dev)
5658 if (__netdev_update_features(dev))
5659 netdev_features_change(dev);
5661 EXPORT_SYMBOL(netdev_update_features);
5664 * netdev_change_features - recalculate device features
5665 * @dev: the device to check
5667 * Recalculate dev->features set and send notifications even
5668 * if they have not changed. Should be called instead of
5669 * netdev_update_features() if also dev->vlan_features might
5670 * have changed to allow the changes to be propagated to stacked
5673 void netdev_change_features(struct net_device *dev)
5675 __netdev_update_features(dev);
5676 netdev_features_change(dev);
5678 EXPORT_SYMBOL(netdev_change_features);
5681 * netif_stacked_transfer_operstate - transfer operstate
5682 * @rootdev: the root or lower level device to transfer state from
5683 * @dev: the device to transfer operstate to
5685 * Transfer operational state from root to device. This is normally
5686 * called when a stacking relationship exists between the root
5687 * device and the device(a leaf device).
5689 void netif_stacked_transfer_operstate(const struct net_device *rootdev,
5690 struct net_device *dev)
5692 if (rootdev->operstate == IF_OPER_DORMANT)
5693 netif_dormant_on(dev);
5695 netif_dormant_off(dev);
5697 if (netif_carrier_ok(rootdev)) {
5698 if (!netif_carrier_ok(dev))
5699 netif_carrier_on(dev);
5701 if (netif_carrier_ok(dev))
5702 netif_carrier_off(dev);
5705 EXPORT_SYMBOL(netif_stacked_transfer_operstate);
5708 static int netif_alloc_rx_queues(struct net_device *dev)
5710 unsigned int i, count = dev->num_rx_queues;
5711 struct netdev_rx_queue *rx;
5715 rx = kcalloc(count, sizeof(struct netdev_rx_queue), GFP_KERNEL);
5721 for (i = 0; i < count; i++)
5727 static void netdev_init_one_queue(struct net_device *dev,
5728 struct netdev_queue *queue, void *_unused)
5730 /* Initialize queue lock */
5731 spin_lock_init(&queue->_xmit_lock);
5732 netdev_set_xmit_lockdep_class(&queue->_xmit_lock, dev->type);
5733 queue->xmit_lock_owner = -1;
5734 netdev_queue_numa_node_write(queue, NUMA_NO_NODE);
5737 dql_init(&queue->dql, HZ);
5741 static void netif_free_tx_queues(struct net_device *dev)
5743 if (is_vmalloc_addr(dev->_tx))
5749 static int netif_alloc_netdev_queues(struct net_device *dev)
5751 unsigned int count = dev->num_tx_queues;
5752 struct netdev_queue *tx;
5753 size_t sz = count * sizeof(*tx);
5755 BUG_ON(count < 1 || count > 0xffff);
5757 tx = kzalloc(sz, GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT);
5765 netdev_for_each_tx_queue(dev, netdev_init_one_queue, NULL);
5766 spin_lock_init(&dev->tx_global_lock);
5772 * register_netdevice - register a network device
5773 * @dev: device to register
5775 * Take a completed network device structure and add it to the kernel
5776 * interfaces. A %NETDEV_REGISTER message is sent to the netdev notifier
5777 * chain. 0 is returned on success. A negative errno code is returned
5778 * on a failure to set up the device, or if the name is a duplicate.
5780 * Callers must hold the rtnl semaphore. You may want
5781 * register_netdev() instead of this.
5784 * The locking appears insufficient to guarantee two parallel registers
5785 * will not get the same name.
5788 int register_netdevice(struct net_device *dev)
5791 struct net *net = dev_net(dev);
5793 BUG_ON(dev_boot_phase);
5798 /* When net_device's are persistent, this will be fatal. */
5799 BUG_ON(dev->reg_state != NETREG_UNINITIALIZED);
5802 spin_lock_init(&dev->addr_list_lock);
5803 netdev_set_addr_lockdep_class(dev);
5807 ret = dev_get_valid_name(net, dev, dev->name);
5811 /* Init, if this function is available */
5812 if (dev->netdev_ops->ndo_init) {
5813 ret = dev->netdev_ops->ndo_init(dev);
5821 if (((dev->hw_features | dev->features) &
5822 NETIF_F_HW_VLAN_CTAG_FILTER) &&
5823 (!dev->netdev_ops->ndo_vlan_rx_add_vid ||
5824 !dev->netdev_ops->ndo_vlan_rx_kill_vid)) {
5825 netdev_WARN(dev, "Buggy VLAN acceleration in driver!\n");
5832 dev->ifindex = dev_new_index(net);
5833 else if (__dev_get_by_index(net, dev->ifindex))
5836 if (dev->iflink == -1)
5837 dev->iflink = dev->ifindex;
5839 /* Transfer changeable features to wanted_features and enable
5840 * software offloads (GSO and GRO).
5842 dev->hw_features |= NETIF_F_SOFT_FEATURES;
5843 dev->features |= NETIF_F_SOFT_FEATURES;
5844 dev->wanted_features = dev->features & dev->hw_features;
5846 if (!(dev->flags & IFF_LOOPBACK)) {
5847 dev->hw_features |= NETIF_F_NOCACHE_COPY;
5850 /* Make NETIF_F_HIGHDMA inheritable to VLAN devices.
5852 dev->vlan_features |= NETIF_F_HIGHDMA;
5854 /* Make NETIF_F_SG inheritable to tunnel devices.
5856 dev->hw_enc_features |= NETIF_F_SG;
5858 /* Make NETIF_F_SG inheritable to MPLS.
5860 dev->mpls_features |= NETIF_F_SG;
5862 ret = call_netdevice_notifiers(NETDEV_POST_INIT, dev);
5863 ret = notifier_to_errno(ret);
5867 ret = netdev_register_kobject(dev);
5870 dev->reg_state = NETREG_REGISTERED;
5872 __netdev_update_features(dev);
5875 * Default initial state at registry is that the
5876 * device is present.
5879 set_bit(__LINK_STATE_PRESENT, &dev->state);
5881 linkwatch_init_dev(dev);
5883 dev_init_scheduler(dev);
5885 list_netdevice(dev);
5886 add_device_randomness(dev->dev_addr, dev->addr_len);
5888 /* If the device has permanent device address, driver should
5889 * set dev_addr and also addr_assign_type should be set to
5890 * NET_ADDR_PERM (default value).
5892 if (dev->addr_assign_type == NET_ADDR_PERM)
5893 memcpy(dev->perm_addr, dev->dev_addr, dev->addr_len);
5895 /* Notify protocols, that a new device appeared. */
5896 ret = call_netdevice_notifiers(NETDEV_REGISTER, dev);
5897 ret = notifier_to_errno(ret);
5899 rollback_registered(dev);
5900 dev->reg_state = NETREG_UNREGISTERED;
5903 * Prevent userspace races by waiting until the network
5904 * device is fully setup before sending notifications.
5906 if (!dev->rtnl_link_ops ||
5907 dev->rtnl_link_state == RTNL_LINK_INITIALIZED)
5908 rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U, GFP_KERNEL);
5914 if (dev->netdev_ops->ndo_uninit)
5915 dev->netdev_ops->ndo_uninit(dev);
5918 EXPORT_SYMBOL(register_netdevice);
5921 * init_dummy_netdev - init a dummy network device for NAPI
5922 * @dev: device to init
5924 * This takes a network device structure and initialize the minimum
5925 * amount of fields so it can be used to schedule NAPI polls without
5926 * registering a full blown interface. This is to be used by drivers
5927 * that need to tie several hardware interfaces to a single NAPI
5928 * poll scheduler due to HW limitations.
5930 int init_dummy_netdev(struct net_device *dev)
5932 /* Clear everything. Note we don't initialize spinlocks
5933 * are they aren't supposed to be taken by any of the
5934 * NAPI code and this dummy netdev is supposed to be
5935 * only ever used for NAPI polls
5937 memset(dev, 0, sizeof(struct net_device));
5939 /* make sure we BUG if trying to hit standard
5940 * register/unregister code path
5942 dev->reg_state = NETREG_DUMMY;
5944 /* NAPI wants this */
5945 INIT_LIST_HEAD(&dev->napi_list);
5947 /* a dummy interface is started by default */
5948 set_bit(__LINK_STATE_PRESENT, &dev->state);
5949 set_bit(__LINK_STATE_START, &dev->state);
5951 /* Note : We dont allocate pcpu_refcnt for dummy devices,
5952 * because users of this 'device' dont need to change
5958 EXPORT_SYMBOL_GPL(init_dummy_netdev);
5962 * register_netdev - register a network device
5963 * @dev: device to register
5965 * Take a completed network device structure and add it to the kernel
5966 * interfaces. A %NETDEV_REGISTER message is sent to the netdev notifier
5967 * chain. 0 is returned on success. A negative errno code is returned
5968 * on a failure to set up the device, or if the name is a duplicate.
5970 * This is a wrapper around register_netdevice that takes the rtnl semaphore
5971 * and expands the device name if you passed a format string to
5974 int register_netdev(struct net_device *dev)
5979 err = register_netdevice(dev);
5983 EXPORT_SYMBOL(register_netdev);
5985 int netdev_refcnt_read(const struct net_device *dev)
5989 for_each_possible_cpu(i)
5990 refcnt += *per_cpu_ptr(dev->pcpu_refcnt, i);
5993 EXPORT_SYMBOL(netdev_refcnt_read);
5996 * netdev_wait_allrefs - wait until all references are gone.
5997 * @dev: target net_device
5999 * This is called when unregistering network devices.
6001 * Any protocol or device that holds a reference should register
6002 * for netdevice notification, and cleanup and put back the
6003 * reference if they receive an UNREGISTER event.
6004 * We can get stuck here if buggy protocols don't correctly
6007 static void netdev_wait_allrefs(struct net_device *dev)
6009 unsigned long rebroadcast_time, warning_time;
6012 linkwatch_forget_dev(dev);
6014 rebroadcast_time = warning_time = jiffies;
6015 refcnt = netdev_refcnt_read(dev);
6017 while (refcnt != 0) {
6018 if (time_after(jiffies, rebroadcast_time + 1 * HZ)) {
6021 /* Rebroadcast unregister notification */
6022 call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
6028 call_netdevice_notifiers(NETDEV_UNREGISTER_FINAL, dev);
6029 if (test_bit(__LINK_STATE_LINKWATCH_PENDING,
6031 /* We must not have linkwatch events
6032 * pending on unregister. If this
6033 * happens, we simply run the queue
6034 * unscheduled, resulting in a noop
6037 linkwatch_run_queue();
6042 rebroadcast_time = jiffies;
6047 refcnt = netdev_refcnt_read(dev);
6049 if (time_after(jiffies, warning_time + 10 * HZ)) {
6050 pr_emerg("unregister_netdevice: waiting for %s to become free. Usage count = %d\n",
6052 warning_time = jiffies;
6061 * register_netdevice(x1);
6062 * register_netdevice(x2);
6064 * unregister_netdevice(y1);
6065 * unregister_netdevice(y2);
6071 * We are invoked by rtnl_unlock().
6072 * This allows us to deal with problems:
6073 * 1) We can delete sysfs objects which invoke hotplug
6074 * without deadlocking with linkwatch via keventd.
6075 * 2) Since we run with the RTNL semaphore not held, we can sleep
6076 * safely in order to wait for the netdev refcnt to drop to zero.
6078 * We must not return until all unregister events added during
6079 * the interval the lock was held have been completed.
6081 void netdev_run_todo(void)
6083 struct list_head list;
6085 /* Snapshot list, allow later requests */
6086 list_replace_init(&net_todo_list, &list);
6091 /* Wait for rcu callbacks to finish before next phase */
6092 if (!list_empty(&list))
6095 while (!list_empty(&list)) {
6096 struct net_device *dev
6097 = list_first_entry(&list, struct net_device, todo_list);
6098 list_del(&dev->todo_list);
6101 call_netdevice_notifiers(NETDEV_UNREGISTER_FINAL, dev);
6104 if (unlikely(dev->reg_state != NETREG_UNREGISTERING)) {
6105 pr_err("network todo '%s' but state %d\n",
6106 dev->name, dev->reg_state);
6111 dev->reg_state = NETREG_UNREGISTERED;
6113 on_each_cpu(flush_backlog, dev, 1);
6115 netdev_wait_allrefs(dev);
6118 BUG_ON(netdev_refcnt_read(dev));
6119 WARN_ON(rcu_access_pointer(dev->ip_ptr));
6120 WARN_ON(rcu_access_pointer(dev->ip6_ptr));
6121 WARN_ON(dev->dn_ptr);
6123 if (dev->destructor)
6124 dev->destructor(dev);
6126 /* Report a network device has been unregistered */
6128 dev_net(dev)->dev_unreg_count--;
6130 wake_up(&netdev_unregistering_wq);
6132 /* Free network device */
6133 kobject_put(&dev->dev.kobj);
6137 /* Convert net_device_stats to rtnl_link_stats64. They have the same
6138 * fields in the same order, with only the type differing.
6140 void netdev_stats_to_stats64(struct rtnl_link_stats64 *stats64,
6141 const struct net_device_stats *netdev_stats)
6143 #if BITS_PER_LONG == 64
6144 BUILD_BUG_ON(sizeof(*stats64) != sizeof(*netdev_stats));
6145 memcpy(stats64, netdev_stats, sizeof(*stats64));
6147 size_t i, n = sizeof(*stats64) / sizeof(u64);
6148 const unsigned long *src = (const unsigned long *)netdev_stats;
6149 u64 *dst = (u64 *)stats64;
6151 BUILD_BUG_ON(sizeof(*netdev_stats) / sizeof(unsigned long) !=
6152 sizeof(*stats64) / sizeof(u64));
6153 for (i = 0; i < n; i++)
6157 EXPORT_SYMBOL(netdev_stats_to_stats64);
6160 * dev_get_stats - get network device statistics
6161 * @dev: device to get statistics from
6162 * @storage: place to store stats
6164 * Get network statistics from device. Return @storage.
6165 * The device driver may provide its own method by setting
6166 * dev->netdev_ops->get_stats64 or dev->netdev_ops->get_stats;
6167 * otherwise the internal statistics structure is used.
6169 struct rtnl_link_stats64 *dev_get_stats(struct net_device *dev,
6170 struct rtnl_link_stats64 *storage)
6172 const struct net_device_ops *ops = dev->netdev_ops;
6174 if (ops->ndo_get_stats64) {
6175 memset(storage, 0, sizeof(*storage));
6176 ops->ndo_get_stats64(dev, storage);
6177 } else if (ops->ndo_get_stats) {
6178 netdev_stats_to_stats64(storage, ops->ndo_get_stats(dev));
6180 netdev_stats_to_stats64(storage, &dev->stats);
6182 storage->rx_dropped += atomic_long_read(&dev->rx_dropped);
6185 EXPORT_SYMBOL(dev_get_stats);
6187 struct netdev_queue *dev_ingress_queue_create(struct net_device *dev)
6189 struct netdev_queue *queue = dev_ingress_queue(dev);
6191 #ifdef CONFIG_NET_CLS_ACT
6194 queue = kzalloc(sizeof(*queue), GFP_KERNEL);
6197 netdev_init_one_queue(dev, queue, NULL);
6198 queue->qdisc = &noop_qdisc;
6199 queue->qdisc_sleeping = &noop_qdisc;
6200 rcu_assign_pointer(dev->ingress_queue, queue);
6205 static const struct ethtool_ops default_ethtool_ops;
6207 void netdev_set_default_ethtool_ops(struct net_device *dev,
6208 const struct ethtool_ops *ops)
6210 if (dev->ethtool_ops == &default_ethtool_ops)
6211 dev->ethtool_ops = ops;
6213 EXPORT_SYMBOL_GPL(netdev_set_default_ethtool_ops);
6215 void netdev_freemem(struct net_device *dev)
6217 char *addr = (char *)dev - dev->padded;
6219 if (is_vmalloc_addr(addr))
6226 * alloc_netdev_mqs - allocate network device
6227 * @sizeof_priv: size of private data to allocate space for
6228 * @name: device name format string
6229 * @setup: callback to initialize device
6230 * @txqs: the number of TX subqueues to allocate
6231 * @rxqs: the number of RX subqueues to allocate
6233 * Allocates a struct net_device with private data area for driver use
6234 * and performs basic initialization. Also allocates subquue structs
6235 * for each queue on the device.
6237 struct net_device *alloc_netdev_mqs(int sizeof_priv, const char *name,
6238 void (*setup)(struct net_device *),
6239 unsigned int txqs, unsigned int rxqs)
6241 struct net_device *dev;
6243 struct net_device *p;
6245 BUG_ON(strlen(name) >= sizeof(dev->name));
6248 pr_err("alloc_netdev: Unable to allocate device with zero queues\n");
6254 pr_err("alloc_netdev: Unable to allocate device with zero RX queues\n");
6259 alloc_size = sizeof(struct net_device);
6261 /* ensure 32-byte alignment of private area */
6262 alloc_size = ALIGN(alloc_size, NETDEV_ALIGN);
6263 alloc_size += sizeof_priv;
6265 /* ensure 32-byte alignment of whole construct */
6266 alloc_size += NETDEV_ALIGN - 1;
6268 p = kzalloc(alloc_size, GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT);
6270 p = vzalloc(alloc_size);
6274 dev = PTR_ALIGN(p, NETDEV_ALIGN);
6275 dev->padded = (char *)dev - (char *)p;
6277 dev->pcpu_refcnt = alloc_percpu(int);
6278 if (!dev->pcpu_refcnt)
6281 if (dev_addr_init(dev))
6287 dev_net_set(dev, &init_net);
6289 dev->gso_max_size = GSO_MAX_SIZE;
6290 dev->gso_max_segs = GSO_MAX_SEGS;
6292 INIT_LIST_HEAD(&dev->napi_list);
6293 INIT_LIST_HEAD(&dev->unreg_list);
6294 INIT_LIST_HEAD(&dev->close_list);
6295 INIT_LIST_HEAD(&dev->link_watch_list);
6296 INIT_LIST_HEAD(&dev->adj_list.upper);
6297 INIT_LIST_HEAD(&dev->adj_list.lower);
6298 INIT_LIST_HEAD(&dev->all_adj_list.upper);
6299 INIT_LIST_HEAD(&dev->all_adj_list.lower);
6300 dev->priv_flags = IFF_XMIT_DST_RELEASE;
6303 dev->num_tx_queues = txqs;
6304 dev->real_num_tx_queues = txqs;
6305 if (netif_alloc_netdev_queues(dev))
6309 dev->num_rx_queues = rxqs;
6310 dev->real_num_rx_queues = rxqs;
6311 if (netif_alloc_rx_queues(dev))
6315 strcpy(dev->name, name);
6316 dev->group = INIT_NETDEV_GROUP;
6317 if (!dev->ethtool_ops)
6318 dev->ethtool_ops = &default_ethtool_ops;
6326 free_percpu(dev->pcpu_refcnt);
6327 netif_free_tx_queues(dev);
6333 netdev_freemem(dev);
6336 EXPORT_SYMBOL(alloc_netdev_mqs);
6339 * free_netdev - free network device
6342 * This function does the last stage of destroying an allocated device
6343 * interface. The reference to the device object is released.
6344 * If this is the last reference then it will be freed.
6346 void free_netdev(struct net_device *dev)
6348 struct napi_struct *p, *n;
6350 release_net(dev_net(dev));
6352 netif_free_tx_queues(dev);
6357 kfree(rcu_dereference_protected(dev->ingress_queue, 1));
6359 /* Flush device addresses */
6360 dev_addr_flush(dev);
6362 list_for_each_entry_safe(p, n, &dev->napi_list, dev_list)
6365 free_percpu(dev->pcpu_refcnt);
6366 dev->pcpu_refcnt = NULL;
6368 /* Compatibility with error handling in drivers */
6369 if (dev->reg_state == NETREG_UNINITIALIZED) {
6370 netdev_freemem(dev);
6374 BUG_ON(dev->reg_state != NETREG_UNREGISTERED);
6375 dev->reg_state = NETREG_RELEASED;
6377 /* will free via device release */
6378 put_device(&dev->dev);
6380 EXPORT_SYMBOL(free_netdev);
6383 * synchronize_net - Synchronize with packet receive processing
6385 * Wait for packets currently being received to be done.
6386 * Does not block later packets from starting.
6388 void synchronize_net(void)
6391 if (rtnl_is_locked())
6392 synchronize_rcu_expedited();
6396 EXPORT_SYMBOL(synchronize_net);
6399 * unregister_netdevice_queue - remove device from the kernel
6403 * This function shuts down a device interface and removes it
6404 * from the kernel tables.
6405 * If head not NULL, device is queued to be unregistered later.
6407 * Callers must hold the rtnl semaphore. You may want
6408 * unregister_netdev() instead of this.
6411 void unregister_netdevice_queue(struct net_device *dev, struct list_head *head)
6416 list_move_tail(&dev->unreg_list, head);
6418 rollback_registered(dev);
6419 /* Finish processing unregister after unlock */
6423 EXPORT_SYMBOL(unregister_netdevice_queue);
6426 * unregister_netdevice_many - unregister many devices
6427 * @head: list of devices
6429 void unregister_netdevice_many(struct list_head *head)
6431 struct net_device *dev;
6433 if (!list_empty(head)) {
6434 rollback_registered_many(head);
6435 list_for_each_entry(dev, head, unreg_list)
6439 EXPORT_SYMBOL(unregister_netdevice_many);
6442 * unregister_netdev - remove device from the kernel
6445 * This function shuts down a device interface and removes it
6446 * from the kernel tables.
6448 * This is just a wrapper for unregister_netdevice that takes
6449 * the rtnl semaphore. In general you want to use this and not
6450 * unregister_netdevice.
6452 void unregister_netdev(struct net_device *dev)
6455 unregister_netdevice(dev);
6458 EXPORT_SYMBOL(unregister_netdev);
6461 * dev_change_net_namespace - move device to different nethost namespace
6463 * @net: network namespace
6464 * @pat: If not NULL name pattern to try if the current device name
6465 * is already taken in the destination network namespace.
6467 * This function shuts down a device interface and moves it
6468 * to a new network namespace. On success 0 is returned, on
6469 * a failure a netagive errno code is returned.
6471 * Callers must hold the rtnl semaphore.
6474 int dev_change_net_namespace(struct net_device *dev, struct net *net, const char *pat)
6480 /* Don't allow namespace local devices to be moved. */
6482 if (dev->features & NETIF_F_NETNS_LOCAL)
6485 /* Ensure the device has been registrered */
6486 if (dev->reg_state != NETREG_REGISTERED)
6489 /* Get out if there is nothing todo */
6491 if (net_eq(dev_net(dev), net))
6494 /* Pick the destination device name, and ensure
6495 * we can use it in the destination network namespace.
6498 if (__dev_get_by_name(net, dev->name)) {
6499 /* We get here if we can't use the current device name */
6502 if (dev_get_valid_name(net, dev, pat) < 0)
6507 * And now a mini version of register_netdevice unregister_netdevice.
6510 /* If device is running close it first. */
6513 /* And unlink it from device chain */
6515 unlist_netdevice(dev);
6519 /* Shutdown queueing discipline. */
6522 /* Notify protocols, that we are about to destroy
6523 this device. They should clean all the things.
6525 Note that dev->reg_state stays at NETREG_REGISTERED.
6526 This is wanted because this way 8021q and macvlan know
6527 the device is just moving and can keep their slaves up.
6529 call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
6531 call_netdevice_notifiers(NETDEV_UNREGISTER_FINAL, dev);
6532 rtmsg_ifinfo(RTM_DELLINK, dev, ~0U, GFP_KERNEL);
6535 * Flush the unicast and multicast chains
6540 /* Send a netdev-removed uevent to the old namespace */
6541 kobject_uevent(&dev->dev.kobj, KOBJ_REMOVE);
6543 /* Actually switch the network namespace */
6544 dev_net_set(dev, net);
6546 /* If there is an ifindex conflict assign a new one */
6547 if (__dev_get_by_index(net, dev->ifindex)) {
6548 int iflink = (dev->iflink == dev->ifindex);
6549 dev->ifindex = dev_new_index(net);
6551 dev->iflink = dev->ifindex;
6554 /* Send a netdev-add uevent to the new namespace */
6555 kobject_uevent(&dev->dev.kobj, KOBJ_ADD);
6557 /* Fixup kobjects */
6558 err = device_rename(&dev->dev, dev->name);
6561 /* Add the device back in the hashes */
6562 list_netdevice(dev);
6564 /* Notify protocols, that a new device appeared. */
6565 call_netdevice_notifiers(NETDEV_REGISTER, dev);
6568 * Prevent userspace races by waiting until the network
6569 * device is fully setup before sending notifications.
6571 rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U, GFP_KERNEL);
6578 EXPORT_SYMBOL_GPL(dev_change_net_namespace);
6580 static int dev_cpu_callback(struct notifier_block *nfb,
6581 unsigned long action,
6584 struct sk_buff **list_skb;
6585 struct sk_buff *skb;
6586 unsigned int cpu, oldcpu = (unsigned long)ocpu;
6587 struct softnet_data *sd, *oldsd;
6589 if (action != CPU_DEAD && action != CPU_DEAD_FROZEN)
6592 local_irq_disable();
6593 cpu = smp_processor_id();
6594 sd = &per_cpu(softnet_data, cpu);
6595 oldsd = &per_cpu(softnet_data, oldcpu);
6597 /* Find end of our completion_queue. */
6598 list_skb = &sd->completion_queue;
6600 list_skb = &(*list_skb)->next;
6601 /* Append completion queue from offline CPU. */
6602 *list_skb = oldsd->completion_queue;
6603 oldsd->completion_queue = NULL;
6605 /* Append output queue from offline CPU. */
6606 if (oldsd->output_queue) {
6607 *sd->output_queue_tailp = oldsd->output_queue;
6608 sd->output_queue_tailp = oldsd->output_queue_tailp;
6609 oldsd->output_queue = NULL;
6610 oldsd->output_queue_tailp = &oldsd->output_queue;
6612 /* Append NAPI poll list from offline CPU. */
6613 if (!list_empty(&oldsd->poll_list)) {
6614 list_splice_init(&oldsd->poll_list, &sd->poll_list);
6615 raise_softirq_irqoff(NET_RX_SOFTIRQ);
6618 raise_softirq_irqoff(NET_TX_SOFTIRQ);
6621 /* Process offline CPU's input_pkt_queue */
6622 while ((skb = __skb_dequeue(&oldsd->process_queue))) {
6624 input_queue_head_incr(oldsd);
6626 while ((skb = __skb_dequeue(&oldsd->input_pkt_queue))) {
6628 input_queue_head_incr(oldsd);
6636 * netdev_increment_features - increment feature set by one
6637 * @all: current feature set
6638 * @one: new feature set
6639 * @mask: mask feature set
6641 * Computes a new feature set after adding a device with feature set
6642 * @one to the master device with current feature set @all. Will not
6643 * enable anything that is off in @mask. Returns the new feature set.
6645 netdev_features_t netdev_increment_features(netdev_features_t all,
6646 netdev_features_t one, netdev_features_t mask)
6648 if (mask & NETIF_F_GEN_CSUM)
6649 mask |= NETIF_F_ALL_CSUM;
6650 mask |= NETIF_F_VLAN_CHALLENGED;
6652 all |= one & (NETIF_F_ONE_FOR_ALL|NETIF_F_ALL_CSUM) & mask;
6653 all &= one | ~NETIF_F_ALL_FOR_ALL;
6655 /* If one device supports hw checksumming, set for all. */
6656 if (all & NETIF_F_GEN_CSUM)
6657 all &= ~(NETIF_F_ALL_CSUM & ~NETIF_F_GEN_CSUM);
6661 EXPORT_SYMBOL(netdev_increment_features);
6663 static struct hlist_head * __net_init netdev_create_hash(void)
6666 struct hlist_head *hash;
6668 hash = kmalloc(sizeof(*hash) * NETDEV_HASHENTRIES, GFP_KERNEL);
6670 for (i = 0; i < NETDEV_HASHENTRIES; i++)
6671 INIT_HLIST_HEAD(&hash[i]);
6676 /* Initialize per network namespace state */
6677 static int __net_init netdev_init(struct net *net)
6679 if (net != &init_net)
6680 INIT_LIST_HEAD(&net->dev_base_head);
6682 net->dev_name_head = netdev_create_hash();
6683 if (net->dev_name_head == NULL)
6686 net->dev_index_head = netdev_create_hash();
6687 if (net->dev_index_head == NULL)
6693 kfree(net->dev_name_head);
6699 * netdev_drivername - network driver for the device
6700 * @dev: network device
6702 * Determine network driver for device.
6704 const char *netdev_drivername(const struct net_device *dev)
6706 const struct device_driver *driver;
6707 const struct device *parent;
6708 const char *empty = "";
6710 parent = dev->dev.parent;
6714 driver = parent->driver;
6715 if (driver && driver->name)
6716 return driver->name;
6720 static int __netdev_printk(const char *level, const struct net_device *dev,
6721 struct va_format *vaf)
6725 if (dev && dev->dev.parent) {
6726 r = dev_printk_emit(level[1] - '0',
6729 dev_driver_string(dev->dev.parent),
6730 dev_name(dev->dev.parent),
6731 netdev_name(dev), vaf);
6733 r = printk("%s%s: %pV", level, netdev_name(dev), vaf);
6735 r = printk("%s(NULL net_device): %pV", level, vaf);
6741 int netdev_printk(const char *level, const struct net_device *dev,
6742 const char *format, ...)
6744 struct va_format vaf;
6748 va_start(args, format);
6753 r = __netdev_printk(level, dev, &vaf);
6759 EXPORT_SYMBOL(netdev_printk);
6761 #define define_netdev_printk_level(func, level) \
6762 int func(const struct net_device *dev, const char *fmt, ...) \
6765 struct va_format vaf; \
6768 va_start(args, fmt); \
6773 r = __netdev_printk(level, dev, &vaf); \
6779 EXPORT_SYMBOL(func);
6781 define_netdev_printk_level(netdev_emerg, KERN_EMERG);
6782 define_netdev_printk_level(netdev_alert, KERN_ALERT);
6783 define_netdev_printk_level(netdev_crit, KERN_CRIT);
6784 define_netdev_printk_level(netdev_err, KERN_ERR);
6785 define_netdev_printk_level(netdev_warn, KERN_WARNING);
6786 define_netdev_printk_level(netdev_notice, KERN_NOTICE);
6787 define_netdev_printk_level(netdev_info, KERN_INFO);
6789 static void __net_exit netdev_exit(struct net *net)
6791 kfree(net->dev_name_head);
6792 kfree(net->dev_index_head);
6795 static struct pernet_operations __net_initdata netdev_net_ops = {
6796 .init = netdev_init,
6797 .exit = netdev_exit,
6800 static void __net_exit default_device_exit(struct net *net)
6802 struct net_device *dev, *aux;
6804 * Push all migratable network devices back to the
6805 * initial network namespace
6808 for_each_netdev_safe(net, dev, aux) {
6810 char fb_name[IFNAMSIZ];
6812 /* Ignore unmoveable devices (i.e. loopback) */
6813 if (dev->features & NETIF_F_NETNS_LOCAL)
6816 /* Leave virtual devices for the generic cleanup */
6817 if (dev->rtnl_link_ops)
6820 /* Push remaining network devices to init_net */
6821 snprintf(fb_name, IFNAMSIZ, "dev%d", dev->ifindex);
6822 err = dev_change_net_namespace(dev, &init_net, fb_name);
6824 pr_emerg("%s: failed to move %s to init_net: %d\n",
6825 __func__, dev->name, err);
6832 static void __net_exit rtnl_lock_unregistering(struct list_head *net_list)
6834 /* Return with the rtnl_lock held when there are no network
6835 * devices unregistering in any network namespace in net_list.
6842 prepare_to_wait(&netdev_unregistering_wq, &wait,
6843 TASK_UNINTERRUPTIBLE);
6844 unregistering = false;
6846 list_for_each_entry(net, net_list, exit_list) {
6847 if (net->dev_unreg_count > 0) {
6848 unregistering = true;
6857 finish_wait(&netdev_unregistering_wq, &wait);
6860 static void __net_exit default_device_exit_batch(struct list_head *net_list)
6862 /* At exit all network devices most be removed from a network
6863 * namespace. Do this in the reverse order of registration.
6864 * Do this across as many network namespaces as possible to
6865 * improve batching efficiency.
6867 struct net_device *dev;
6869 LIST_HEAD(dev_kill_list);
6871 /* To prevent network device cleanup code from dereferencing
6872 * loopback devices or network devices that have been freed
6873 * wait here for all pending unregistrations to complete,
6874 * before unregistring the loopback device and allowing the
6875 * network namespace be freed.
6877 * The netdev todo list containing all network devices
6878 * unregistrations that happen in default_device_exit_batch
6879 * will run in the rtnl_unlock() at the end of
6880 * default_device_exit_batch.
6882 rtnl_lock_unregistering(net_list);
6883 list_for_each_entry(net, net_list, exit_list) {
6884 for_each_netdev_reverse(net, dev) {
6885 if (dev->rtnl_link_ops)
6886 dev->rtnl_link_ops->dellink(dev, &dev_kill_list);
6888 unregister_netdevice_queue(dev, &dev_kill_list);
6891 unregister_netdevice_many(&dev_kill_list);
6892 list_del(&dev_kill_list);
6896 static struct pernet_operations __net_initdata default_device_ops = {
6897 .exit = default_device_exit,
6898 .exit_batch = default_device_exit_batch,
6902 * Initialize the DEV module. At boot time this walks the device list and
6903 * unhooks any devices that fail to initialise (normally hardware not
6904 * present) and leaves us with a valid list of present and active devices.
6909 * This is called single threaded during boot, so no need
6910 * to take the rtnl semaphore.
6912 static int __init net_dev_init(void)
6914 int i, rc = -ENOMEM;
6916 BUG_ON(!dev_boot_phase);
6918 if (dev_proc_init())
6921 if (netdev_kobject_init())
6924 INIT_LIST_HEAD(&ptype_all);
6925 for (i = 0; i < PTYPE_HASH_SIZE; i++)
6926 INIT_LIST_HEAD(&ptype_base[i]);
6928 INIT_LIST_HEAD(&offload_base);
6930 if (register_pernet_subsys(&netdev_net_ops))
6934 * Initialise the packet receive queues.
6937 for_each_possible_cpu(i) {
6938 struct softnet_data *sd = &per_cpu(softnet_data, i);
6940 memset(sd, 0, sizeof(*sd));
6941 skb_queue_head_init(&sd->input_pkt_queue);
6942 skb_queue_head_init(&sd->process_queue);
6943 sd->completion_queue = NULL;
6944 INIT_LIST_HEAD(&sd->poll_list);
6945 sd->output_queue = NULL;
6946 sd->output_queue_tailp = &sd->output_queue;
6948 sd->csd.func = rps_trigger_softirq;
6954 sd->backlog.poll = process_backlog;
6955 sd->backlog.weight = weight_p;
6956 sd->backlog.gro_list = NULL;
6957 sd->backlog.gro_count = 0;
6959 #ifdef CONFIG_NET_FLOW_LIMIT
6960 sd->flow_limit = NULL;
6966 /* The loopback device is special if any other network devices
6967 * is present in a network namespace the loopback device must
6968 * be present. Since we now dynamically allocate and free the
6969 * loopback device ensure this invariant is maintained by
6970 * keeping the loopback device as the first device on the
6971 * list of network devices. Ensuring the loopback devices
6972 * is the first device that appears and the last network device
6975 if (register_pernet_device(&loopback_net_ops))
6978 if (register_pernet_device(&default_device_ops))
6981 open_softirq(NET_TX_SOFTIRQ, net_tx_action);
6982 open_softirq(NET_RX_SOFTIRQ, net_rx_action);
6984 hotcpu_notifier(dev_cpu_callback, 0);
6991 subsys_initcall(net_dev_init);