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;
150 static int netif_rx_internal(struct sk_buff *skb);
153 * The @dev_base_head list is protected by @dev_base_lock and the rtnl
156 * Pure readers hold dev_base_lock for reading, or rcu_read_lock()
158 * Writers must hold the rtnl semaphore while they loop through the
159 * dev_base_head list, and hold dev_base_lock for writing when they do the
160 * actual updates. This allows pure readers to access the list even
161 * while a writer is preparing to update it.
163 * To put it another way, dev_base_lock is held for writing only to
164 * protect against pure readers; the rtnl semaphore provides the
165 * protection against other writers.
167 * See, for example usages, register_netdevice() and
168 * unregister_netdevice(), which must be called with the rtnl
171 DEFINE_RWLOCK(dev_base_lock);
172 EXPORT_SYMBOL(dev_base_lock);
174 /* protects napi_hash addition/deletion and napi_gen_id */
175 static DEFINE_SPINLOCK(napi_hash_lock);
177 static unsigned int napi_gen_id;
178 static DEFINE_HASHTABLE(napi_hash, 8);
180 static seqcount_t devnet_rename_seq;
182 static inline void dev_base_seq_inc(struct net *net)
184 while (++net->dev_base_seq == 0);
187 static inline struct hlist_head *dev_name_hash(struct net *net, const char *name)
189 unsigned int hash = full_name_hash(name, strnlen(name, IFNAMSIZ));
191 return &net->dev_name_head[hash_32(hash, NETDEV_HASHBITS)];
194 static inline struct hlist_head *dev_index_hash(struct net *net, int ifindex)
196 return &net->dev_index_head[ifindex & (NETDEV_HASHENTRIES - 1)];
199 static inline void rps_lock(struct softnet_data *sd)
202 spin_lock(&sd->input_pkt_queue.lock);
206 static inline void rps_unlock(struct softnet_data *sd)
209 spin_unlock(&sd->input_pkt_queue.lock);
213 /* Device list insertion */
214 static void list_netdevice(struct net_device *dev)
216 struct net *net = dev_net(dev);
220 write_lock_bh(&dev_base_lock);
221 list_add_tail_rcu(&dev->dev_list, &net->dev_base_head);
222 hlist_add_head_rcu(&dev->name_hlist, dev_name_hash(net, dev->name));
223 hlist_add_head_rcu(&dev->index_hlist,
224 dev_index_hash(net, dev->ifindex));
225 write_unlock_bh(&dev_base_lock);
227 dev_base_seq_inc(net);
230 /* Device list removal
231 * caller must respect a RCU grace period before freeing/reusing dev
233 static void unlist_netdevice(struct net_device *dev)
237 /* Unlink dev from the device chain */
238 write_lock_bh(&dev_base_lock);
239 list_del_rcu(&dev->dev_list);
240 hlist_del_rcu(&dev->name_hlist);
241 hlist_del_rcu(&dev->index_hlist);
242 write_unlock_bh(&dev_base_lock);
244 dev_base_seq_inc(dev_net(dev));
251 static RAW_NOTIFIER_HEAD(netdev_chain);
254 * Device drivers call our routines to queue packets here. We empty the
255 * queue in the local softnet handler.
258 DEFINE_PER_CPU_ALIGNED(struct softnet_data, softnet_data);
259 EXPORT_PER_CPU_SYMBOL(softnet_data);
261 #ifdef CONFIG_LOCKDEP
263 * register_netdevice() inits txq->_xmit_lock and sets lockdep class
264 * according to dev->type
266 static const unsigned short netdev_lock_type[] =
267 {ARPHRD_NETROM, ARPHRD_ETHER, ARPHRD_EETHER, ARPHRD_AX25,
268 ARPHRD_PRONET, ARPHRD_CHAOS, ARPHRD_IEEE802, ARPHRD_ARCNET,
269 ARPHRD_APPLETLK, ARPHRD_DLCI, ARPHRD_ATM, ARPHRD_METRICOM,
270 ARPHRD_IEEE1394, ARPHRD_EUI64, ARPHRD_INFINIBAND, ARPHRD_SLIP,
271 ARPHRD_CSLIP, ARPHRD_SLIP6, ARPHRD_CSLIP6, ARPHRD_RSRVD,
272 ARPHRD_ADAPT, ARPHRD_ROSE, ARPHRD_X25, ARPHRD_HWX25,
273 ARPHRD_PPP, ARPHRD_CISCO, ARPHRD_LAPB, ARPHRD_DDCMP,
274 ARPHRD_RAWHDLC, ARPHRD_TUNNEL, ARPHRD_TUNNEL6, ARPHRD_FRAD,
275 ARPHRD_SKIP, ARPHRD_LOOPBACK, ARPHRD_LOCALTLK, ARPHRD_FDDI,
276 ARPHRD_BIF, ARPHRD_SIT, ARPHRD_IPDDP, ARPHRD_IPGRE,
277 ARPHRD_PIMREG, ARPHRD_HIPPI, ARPHRD_ASH, ARPHRD_ECONET,
278 ARPHRD_IRDA, ARPHRD_FCPP, ARPHRD_FCAL, ARPHRD_FCPL,
279 ARPHRD_FCFABRIC, ARPHRD_IEEE80211, ARPHRD_IEEE80211_PRISM,
280 ARPHRD_IEEE80211_RADIOTAP, ARPHRD_PHONET, ARPHRD_PHONET_PIPE,
281 ARPHRD_IEEE802154, ARPHRD_VOID, ARPHRD_NONE};
283 static const char *const netdev_lock_name[] =
284 {"_xmit_NETROM", "_xmit_ETHER", "_xmit_EETHER", "_xmit_AX25",
285 "_xmit_PRONET", "_xmit_CHAOS", "_xmit_IEEE802", "_xmit_ARCNET",
286 "_xmit_APPLETLK", "_xmit_DLCI", "_xmit_ATM", "_xmit_METRICOM",
287 "_xmit_IEEE1394", "_xmit_EUI64", "_xmit_INFINIBAND", "_xmit_SLIP",
288 "_xmit_CSLIP", "_xmit_SLIP6", "_xmit_CSLIP6", "_xmit_RSRVD",
289 "_xmit_ADAPT", "_xmit_ROSE", "_xmit_X25", "_xmit_HWX25",
290 "_xmit_PPP", "_xmit_CISCO", "_xmit_LAPB", "_xmit_DDCMP",
291 "_xmit_RAWHDLC", "_xmit_TUNNEL", "_xmit_TUNNEL6", "_xmit_FRAD",
292 "_xmit_SKIP", "_xmit_LOOPBACK", "_xmit_LOCALTLK", "_xmit_FDDI",
293 "_xmit_BIF", "_xmit_SIT", "_xmit_IPDDP", "_xmit_IPGRE",
294 "_xmit_PIMREG", "_xmit_HIPPI", "_xmit_ASH", "_xmit_ECONET",
295 "_xmit_IRDA", "_xmit_FCPP", "_xmit_FCAL", "_xmit_FCPL",
296 "_xmit_FCFABRIC", "_xmit_IEEE80211", "_xmit_IEEE80211_PRISM",
297 "_xmit_IEEE80211_RADIOTAP", "_xmit_PHONET", "_xmit_PHONET_PIPE",
298 "_xmit_IEEE802154", "_xmit_VOID", "_xmit_NONE"};
300 static struct lock_class_key netdev_xmit_lock_key[ARRAY_SIZE(netdev_lock_type)];
301 static struct lock_class_key netdev_addr_lock_key[ARRAY_SIZE(netdev_lock_type)];
303 static inline unsigned short netdev_lock_pos(unsigned short dev_type)
307 for (i = 0; i < ARRAY_SIZE(netdev_lock_type); i++)
308 if (netdev_lock_type[i] == dev_type)
310 /* the last key is used by default */
311 return ARRAY_SIZE(netdev_lock_type) - 1;
314 static inline void netdev_set_xmit_lockdep_class(spinlock_t *lock,
315 unsigned short dev_type)
319 i = netdev_lock_pos(dev_type);
320 lockdep_set_class_and_name(lock, &netdev_xmit_lock_key[i],
321 netdev_lock_name[i]);
324 static inline void netdev_set_addr_lockdep_class(struct net_device *dev)
328 i = netdev_lock_pos(dev->type);
329 lockdep_set_class_and_name(&dev->addr_list_lock,
330 &netdev_addr_lock_key[i],
331 netdev_lock_name[i]);
334 static inline void netdev_set_xmit_lockdep_class(spinlock_t *lock,
335 unsigned short dev_type)
338 static inline void netdev_set_addr_lockdep_class(struct net_device *dev)
343 /*******************************************************************************
345 Protocol management and registration routines
347 *******************************************************************************/
350 * Add a protocol ID to the list. Now that the input handler is
351 * smarter we can dispense with all the messy stuff that used to be
354 * BEWARE!!! Protocol handlers, mangling input packets,
355 * MUST BE last in hash buckets and checking protocol handlers
356 * MUST start from promiscuous ptype_all chain in net_bh.
357 * It is true now, do not change it.
358 * Explanation follows: if protocol handler, mangling packet, will
359 * be the first on list, it is not able to sense, that packet
360 * is cloned and should be copied-on-write, so that it will
361 * change it and subsequent readers will get broken packet.
365 static inline struct list_head *ptype_head(const struct packet_type *pt)
367 if (pt->type == htons(ETH_P_ALL))
370 return &ptype_base[ntohs(pt->type) & PTYPE_HASH_MASK];
374 * dev_add_pack - add packet handler
375 * @pt: packet type declaration
377 * Add a protocol handler to the networking stack. The passed &packet_type
378 * is linked into kernel lists and may not be freed until it has been
379 * removed from the kernel lists.
381 * This call does not sleep therefore it can not
382 * guarantee all CPU's that are in middle of receiving packets
383 * will see the new packet type (until the next received packet).
386 void dev_add_pack(struct packet_type *pt)
388 struct list_head *head = ptype_head(pt);
390 spin_lock(&ptype_lock);
391 list_add_rcu(&pt->list, head);
392 spin_unlock(&ptype_lock);
394 EXPORT_SYMBOL(dev_add_pack);
397 * __dev_remove_pack - remove packet handler
398 * @pt: packet type declaration
400 * Remove a protocol handler that was previously added to the kernel
401 * protocol handlers by dev_add_pack(). The passed &packet_type is removed
402 * from the kernel lists and can be freed or reused once this function
405 * The packet type might still be in use by receivers
406 * and must not be freed until after all the CPU's have gone
407 * through a quiescent state.
409 void __dev_remove_pack(struct packet_type *pt)
411 struct list_head *head = ptype_head(pt);
412 struct packet_type *pt1;
414 spin_lock(&ptype_lock);
416 list_for_each_entry(pt1, head, list) {
418 list_del_rcu(&pt->list);
423 pr_warn("dev_remove_pack: %p not found\n", pt);
425 spin_unlock(&ptype_lock);
427 EXPORT_SYMBOL(__dev_remove_pack);
430 * dev_remove_pack - remove packet handler
431 * @pt: packet type declaration
433 * Remove a protocol handler that was previously added to the kernel
434 * protocol handlers by dev_add_pack(). The passed &packet_type is removed
435 * from the kernel lists and can be freed or reused once this function
438 * This call sleeps to guarantee that no CPU is looking at the packet
441 void dev_remove_pack(struct packet_type *pt)
443 __dev_remove_pack(pt);
447 EXPORT_SYMBOL(dev_remove_pack);
451 * dev_add_offload - register offload handlers
452 * @po: protocol offload declaration
454 * Add protocol offload handlers to the networking stack. The passed
455 * &proto_offload is linked into kernel lists and may not be freed until
456 * it has been removed from the kernel lists.
458 * This call does not sleep therefore it can not
459 * guarantee all CPU's that are in middle of receiving packets
460 * will see the new offload handlers (until the next received packet).
462 void dev_add_offload(struct packet_offload *po)
464 struct list_head *head = &offload_base;
466 spin_lock(&offload_lock);
467 list_add_rcu(&po->list, head);
468 spin_unlock(&offload_lock);
470 EXPORT_SYMBOL(dev_add_offload);
473 * __dev_remove_offload - remove offload handler
474 * @po: packet offload declaration
476 * Remove a protocol offload handler that was previously added to the
477 * kernel offload handlers by dev_add_offload(). The passed &offload_type
478 * is removed from the kernel lists and can be freed or reused once this
481 * The packet type might still be in use by receivers
482 * and must not be freed until after all the CPU's have gone
483 * through a quiescent state.
485 static void __dev_remove_offload(struct packet_offload *po)
487 struct list_head *head = &offload_base;
488 struct packet_offload *po1;
490 spin_lock(&offload_lock);
492 list_for_each_entry(po1, head, list) {
494 list_del_rcu(&po->list);
499 pr_warn("dev_remove_offload: %p not found\n", po);
501 spin_unlock(&offload_lock);
505 * dev_remove_offload - remove packet offload handler
506 * @po: packet offload declaration
508 * Remove a packet offload handler that was previously added to the kernel
509 * offload handlers by dev_add_offload(). The passed &offload_type is
510 * removed from the kernel lists and can be freed or reused once this
513 * This call sleeps to guarantee that no CPU is looking at the packet
516 void dev_remove_offload(struct packet_offload *po)
518 __dev_remove_offload(po);
522 EXPORT_SYMBOL(dev_remove_offload);
524 /******************************************************************************
526 Device Boot-time Settings Routines
528 *******************************************************************************/
530 /* Boot time configuration table */
531 static struct netdev_boot_setup dev_boot_setup[NETDEV_BOOT_SETUP_MAX];
534 * netdev_boot_setup_add - add new setup entry
535 * @name: name of the device
536 * @map: configured settings for the device
538 * Adds new setup entry to the dev_boot_setup list. The function
539 * returns 0 on error and 1 on success. This is a generic routine to
542 static int netdev_boot_setup_add(char *name, struct ifmap *map)
544 struct netdev_boot_setup *s;
548 for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++) {
549 if (s[i].name[0] == '\0' || s[i].name[0] == ' ') {
550 memset(s[i].name, 0, sizeof(s[i].name));
551 strlcpy(s[i].name, name, IFNAMSIZ);
552 memcpy(&s[i].map, map, sizeof(s[i].map));
557 return i >= NETDEV_BOOT_SETUP_MAX ? 0 : 1;
561 * netdev_boot_setup_check - check boot time settings
562 * @dev: the netdevice
564 * Check boot time settings for the device.
565 * The found settings are set for the device to be used
566 * later in the device probing.
567 * Returns 0 if no settings found, 1 if they are.
569 int netdev_boot_setup_check(struct net_device *dev)
571 struct netdev_boot_setup *s = dev_boot_setup;
574 for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++) {
575 if (s[i].name[0] != '\0' && s[i].name[0] != ' ' &&
576 !strcmp(dev->name, s[i].name)) {
577 dev->irq = s[i].map.irq;
578 dev->base_addr = s[i].map.base_addr;
579 dev->mem_start = s[i].map.mem_start;
580 dev->mem_end = s[i].map.mem_end;
586 EXPORT_SYMBOL(netdev_boot_setup_check);
590 * netdev_boot_base - get address from boot time settings
591 * @prefix: prefix for network device
592 * @unit: id for network device
594 * Check boot time settings for the base address of device.
595 * The found settings are set for the device to be used
596 * later in the device probing.
597 * Returns 0 if no settings found.
599 unsigned long netdev_boot_base(const char *prefix, int unit)
601 const struct netdev_boot_setup *s = dev_boot_setup;
605 sprintf(name, "%s%d", prefix, unit);
608 * If device already registered then return base of 1
609 * to indicate not to probe for this interface
611 if (__dev_get_by_name(&init_net, name))
614 for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++)
615 if (!strcmp(name, s[i].name))
616 return s[i].map.base_addr;
621 * Saves at boot time configured settings for any netdevice.
623 int __init netdev_boot_setup(char *str)
628 str = get_options(str, ARRAY_SIZE(ints), ints);
633 memset(&map, 0, sizeof(map));
637 map.base_addr = ints[2];
639 map.mem_start = ints[3];
641 map.mem_end = ints[4];
643 /* Add new entry to the list */
644 return netdev_boot_setup_add(str, &map);
647 __setup("netdev=", netdev_boot_setup);
649 /*******************************************************************************
651 Device Interface Subroutines
653 *******************************************************************************/
656 * __dev_get_by_name - find a device by its name
657 * @net: the applicable net namespace
658 * @name: name to find
660 * Find an interface by name. Must be called under RTNL semaphore
661 * or @dev_base_lock. If the name is found a pointer to the device
662 * is returned. If the name is not found then %NULL is returned. The
663 * reference counters are not incremented so the caller must be
664 * careful with locks.
667 struct net_device *__dev_get_by_name(struct net *net, const char *name)
669 struct net_device *dev;
670 struct hlist_head *head = dev_name_hash(net, name);
672 hlist_for_each_entry(dev, head, name_hlist)
673 if (!strncmp(dev->name, name, IFNAMSIZ))
678 EXPORT_SYMBOL(__dev_get_by_name);
681 * dev_get_by_name_rcu - find a device by its name
682 * @net: the applicable net namespace
683 * @name: name to find
685 * Find an interface by name.
686 * If the name is found a pointer to the device is returned.
687 * If the name is not found then %NULL is returned.
688 * The reference counters are not incremented so the caller must be
689 * careful with locks. The caller must hold RCU lock.
692 struct net_device *dev_get_by_name_rcu(struct net *net, const char *name)
694 struct net_device *dev;
695 struct hlist_head *head = dev_name_hash(net, name);
697 hlist_for_each_entry_rcu(dev, head, name_hlist)
698 if (!strncmp(dev->name, name, IFNAMSIZ))
703 EXPORT_SYMBOL(dev_get_by_name_rcu);
706 * dev_get_by_name - find a device by its name
707 * @net: the applicable net namespace
708 * @name: name to find
710 * Find an interface by name. This can be called from any
711 * context and does its own locking. The returned handle has
712 * the usage count incremented and the caller must use dev_put() to
713 * release it when it is no longer needed. %NULL is returned if no
714 * matching device is found.
717 struct net_device *dev_get_by_name(struct net *net, const char *name)
719 struct net_device *dev;
722 dev = dev_get_by_name_rcu(net, name);
728 EXPORT_SYMBOL(dev_get_by_name);
731 * __dev_get_by_index - find a device by its ifindex
732 * @net: the applicable net namespace
733 * @ifindex: index of device
735 * Search for an interface by index. Returns %NULL if the device
736 * is not found or a pointer to the device. The device has not
737 * had its reference counter increased so the caller must be careful
738 * about locking. The caller must hold either the RTNL semaphore
742 struct net_device *__dev_get_by_index(struct net *net, int ifindex)
744 struct net_device *dev;
745 struct hlist_head *head = dev_index_hash(net, ifindex);
747 hlist_for_each_entry(dev, head, index_hlist)
748 if (dev->ifindex == ifindex)
753 EXPORT_SYMBOL(__dev_get_by_index);
756 * dev_get_by_index_rcu - find a device by its ifindex
757 * @net: the applicable net namespace
758 * @ifindex: index of device
760 * Search for an interface by index. Returns %NULL if the device
761 * is not found or a pointer to the device. The device has not
762 * had its reference counter increased so the caller must be careful
763 * about locking. The caller must hold RCU lock.
766 struct net_device *dev_get_by_index_rcu(struct net *net, int ifindex)
768 struct net_device *dev;
769 struct hlist_head *head = dev_index_hash(net, ifindex);
771 hlist_for_each_entry_rcu(dev, head, index_hlist)
772 if (dev->ifindex == ifindex)
777 EXPORT_SYMBOL(dev_get_by_index_rcu);
781 * dev_get_by_index - find a device by its ifindex
782 * @net: the applicable net namespace
783 * @ifindex: index of device
785 * Search for an interface by index. Returns NULL if the device
786 * is not found or a pointer to the device. The device returned has
787 * had a reference added and the pointer is safe until the user calls
788 * dev_put to indicate they have finished with it.
791 struct net_device *dev_get_by_index(struct net *net, int ifindex)
793 struct net_device *dev;
796 dev = dev_get_by_index_rcu(net, ifindex);
802 EXPORT_SYMBOL(dev_get_by_index);
805 * netdev_get_name - get a netdevice name, knowing its ifindex.
806 * @net: network namespace
807 * @name: a pointer to the buffer where the name will be stored.
808 * @ifindex: the ifindex of the interface to get the name from.
810 * The use of raw_seqcount_begin() and cond_resched() before
811 * retrying is required as we want to give the writers a chance
812 * to complete when CONFIG_PREEMPT is not set.
814 int netdev_get_name(struct net *net, char *name, int ifindex)
816 struct net_device *dev;
820 seq = raw_seqcount_begin(&devnet_rename_seq);
822 dev = dev_get_by_index_rcu(net, ifindex);
828 strcpy(name, dev->name);
830 if (read_seqcount_retry(&devnet_rename_seq, seq)) {
839 * dev_getbyhwaddr_rcu - find a device by its hardware address
840 * @net: the applicable net namespace
841 * @type: media type of device
842 * @ha: hardware address
844 * Search for an interface by MAC address. Returns NULL if the device
845 * is not found or a pointer to the device.
846 * The caller must hold RCU or RTNL.
847 * The returned device has not had its ref count increased
848 * and the caller must therefore be careful about locking
852 struct net_device *dev_getbyhwaddr_rcu(struct net *net, unsigned short type,
855 struct net_device *dev;
857 for_each_netdev_rcu(net, dev)
858 if (dev->type == type &&
859 !memcmp(dev->dev_addr, ha, dev->addr_len))
864 EXPORT_SYMBOL(dev_getbyhwaddr_rcu);
866 struct net_device *__dev_getfirstbyhwtype(struct net *net, unsigned short type)
868 struct net_device *dev;
871 for_each_netdev(net, dev)
872 if (dev->type == type)
877 EXPORT_SYMBOL(__dev_getfirstbyhwtype);
879 struct net_device *dev_getfirstbyhwtype(struct net *net, unsigned short type)
881 struct net_device *dev, *ret = NULL;
884 for_each_netdev_rcu(net, dev)
885 if (dev->type == type) {
893 EXPORT_SYMBOL(dev_getfirstbyhwtype);
896 * dev_get_by_flags_rcu - find any device with given flags
897 * @net: the applicable net namespace
898 * @if_flags: IFF_* values
899 * @mask: bitmask of bits in if_flags to check
901 * Search for any interface with the given flags. Returns NULL if a device
902 * is not found or a pointer to the device. Must be called inside
903 * rcu_read_lock(), and result refcount is unchanged.
906 struct net_device *dev_get_by_flags_rcu(struct net *net, unsigned short if_flags,
909 struct net_device *dev, *ret;
912 for_each_netdev_rcu(net, dev) {
913 if (((dev->flags ^ if_flags) & mask) == 0) {
920 EXPORT_SYMBOL(dev_get_by_flags_rcu);
923 * dev_valid_name - check if name is okay for network device
926 * Network device names need to be valid file names to
927 * to allow sysfs to work. We also disallow any kind of
930 bool dev_valid_name(const char *name)
934 if (strlen(name) >= IFNAMSIZ)
936 if (!strcmp(name, ".") || !strcmp(name, ".."))
940 if (*name == '/' || isspace(*name))
946 EXPORT_SYMBOL(dev_valid_name);
949 * __dev_alloc_name - allocate a name for a device
950 * @net: network namespace to allocate the device name in
951 * @name: name format string
952 * @buf: scratch buffer and result name string
954 * Passed a format string - eg "lt%d" it will try and find a suitable
955 * id. It scans list of devices to build up a free map, then chooses
956 * the first empty slot. The caller must hold the dev_base or rtnl lock
957 * while allocating the name and adding the device in order to avoid
959 * Limited to bits_per_byte * page size devices (ie 32K on most platforms).
960 * Returns the number of the unit assigned or a negative errno code.
963 static int __dev_alloc_name(struct net *net, const char *name, char *buf)
967 const int max_netdevices = 8*PAGE_SIZE;
968 unsigned long *inuse;
969 struct net_device *d;
971 p = strnchr(name, IFNAMSIZ-1, '%');
974 * Verify the string as this thing may have come from
975 * the user. There must be either one "%d" and no other "%"
978 if (p[1] != 'd' || strchr(p + 2, '%'))
981 /* Use one page as a bit array of possible slots */
982 inuse = (unsigned long *) get_zeroed_page(GFP_ATOMIC);
986 for_each_netdev(net, d) {
987 if (!sscanf(d->name, name, &i))
989 if (i < 0 || i >= max_netdevices)
992 /* avoid cases where sscanf is not exact inverse of printf */
993 snprintf(buf, IFNAMSIZ, name, i);
994 if (!strncmp(buf, d->name, IFNAMSIZ))
998 i = find_first_zero_bit(inuse, max_netdevices);
999 free_page((unsigned long) inuse);
1003 snprintf(buf, IFNAMSIZ, name, i);
1004 if (!__dev_get_by_name(net, buf))
1007 /* It is possible to run out of possible slots
1008 * when the name is long and there isn't enough space left
1009 * for the digits, or if all bits are used.
1015 * dev_alloc_name - allocate a name for a device
1017 * @name: name format string
1019 * Passed a format string - eg "lt%d" it will try and find a suitable
1020 * id. It scans list of devices to build up a free map, then chooses
1021 * the first empty slot. The caller must hold the dev_base or rtnl lock
1022 * while allocating the name and adding the device in order to avoid
1024 * Limited to bits_per_byte * page size devices (ie 32K on most platforms).
1025 * Returns the number of the unit assigned or a negative errno code.
1028 int dev_alloc_name(struct net_device *dev, const char *name)
1034 BUG_ON(!dev_net(dev));
1036 ret = __dev_alloc_name(net, name, buf);
1038 strlcpy(dev->name, buf, IFNAMSIZ);
1041 EXPORT_SYMBOL(dev_alloc_name);
1043 static int dev_alloc_name_ns(struct net *net,
1044 struct net_device *dev,
1050 ret = __dev_alloc_name(net, name, buf);
1052 strlcpy(dev->name, buf, IFNAMSIZ);
1056 static int dev_get_valid_name(struct net *net,
1057 struct net_device *dev,
1062 if (!dev_valid_name(name))
1065 if (strchr(name, '%'))
1066 return dev_alloc_name_ns(net, dev, name);
1067 else if (__dev_get_by_name(net, name))
1069 else if (dev->name != name)
1070 strlcpy(dev->name, name, IFNAMSIZ);
1076 * dev_change_name - change name of a device
1078 * @newname: name (or format string) must be at least IFNAMSIZ
1080 * Change name of a device, can pass format strings "eth%d".
1083 int dev_change_name(struct net_device *dev, const char *newname)
1085 char oldname[IFNAMSIZ];
1091 BUG_ON(!dev_net(dev));
1094 if (dev->flags & IFF_UP)
1097 write_seqcount_begin(&devnet_rename_seq);
1099 if (strncmp(newname, dev->name, IFNAMSIZ) == 0) {
1100 write_seqcount_end(&devnet_rename_seq);
1104 memcpy(oldname, dev->name, IFNAMSIZ);
1106 err = dev_get_valid_name(net, dev, newname);
1108 write_seqcount_end(&devnet_rename_seq);
1113 ret = device_rename(&dev->dev, dev->name);
1115 memcpy(dev->name, oldname, IFNAMSIZ);
1116 write_seqcount_end(&devnet_rename_seq);
1120 write_seqcount_end(&devnet_rename_seq);
1122 netdev_adjacent_rename_links(dev, oldname);
1124 write_lock_bh(&dev_base_lock);
1125 hlist_del_rcu(&dev->name_hlist);
1126 write_unlock_bh(&dev_base_lock);
1130 write_lock_bh(&dev_base_lock);
1131 hlist_add_head_rcu(&dev->name_hlist, dev_name_hash(net, dev->name));
1132 write_unlock_bh(&dev_base_lock);
1134 ret = call_netdevice_notifiers(NETDEV_CHANGENAME, dev);
1135 ret = notifier_to_errno(ret);
1138 /* err >= 0 after dev_alloc_name() or stores the first errno */
1141 write_seqcount_begin(&devnet_rename_seq);
1142 memcpy(dev->name, oldname, IFNAMSIZ);
1143 memcpy(oldname, newname, IFNAMSIZ);
1146 pr_err("%s: name change rollback failed: %d\n",
1155 * dev_set_alias - change ifalias of a device
1157 * @alias: name up to IFALIASZ
1158 * @len: limit of bytes to copy from info
1160 * Set ifalias for a device,
1162 int dev_set_alias(struct net_device *dev, const char *alias, size_t len)
1168 if (len >= IFALIASZ)
1172 kfree(dev->ifalias);
1173 dev->ifalias = NULL;
1177 new_ifalias = krealloc(dev->ifalias, len + 1, GFP_KERNEL);
1180 dev->ifalias = new_ifalias;
1182 strlcpy(dev->ifalias, alias, len+1);
1188 * netdev_features_change - device changes features
1189 * @dev: device to cause notification
1191 * Called to indicate a device has changed features.
1193 void netdev_features_change(struct net_device *dev)
1195 call_netdevice_notifiers(NETDEV_FEAT_CHANGE, dev);
1197 EXPORT_SYMBOL(netdev_features_change);
1200 * netdev_state_change - device changes state
1201 * @dev: device to cause notification
1203 * Called to indicate a device has changed state. This function calls
1204 * the notifier chains for netdev_chain and sends a NEWLINK message
1205 * to the routing socket.
1207 void netdev_state_change(struct net_device *dev)
1209 if (dev->flags & IFF_UP) {
1210 call_netdevice_notifiers(NETDEV_CHANGE, dev);
1211 rtmsg_ifinfo(RTM_NEWLINK, dev, 0, GFP_KERNEL);
1214 EXPORT_SYMBOL(netdev_state_change);
1217 * netdev_notify_peers - notify network peers about existence of @dev
1218 * @dev: network device
1220 * Generate traffic such that interested network peers are aware of
1221 * @dev, such as by generating a gratuitous ARP. This may be used when
1222 * a device wants to inform the rest of the network about some sort of
1223 * reconfiguration such as a failover event or virtual machine
1226 void netdev_notify_peers(struct net_device *dev)
1229 call_netdevice_notifiers(NETDEV_NOTIFY_PEERS, dev);
1232 EXPORT_SYMBOL(netdev_notify_peers);
1234 static int __dev_open(struct net_device *dev)
1236 const struct net_device_ops *ops = dev->netdev_ops;
1241 if (!netif_device_present(dev))
1244 /* Block netpoll from trying to do any rx path servicing.
1245 * If we don't do this there is a chance ndo_poll_controller
1246 * or ndo_poll may be running while we open the device
1248 netpoll_rx_disable(dev);
1250 ret = call_netdevice_notifiers(NETDEV_PRE_UP, dev);
1251 ret = notifier_to_errno(ret);
1255 set_bit(__LINK_STATE_START, &dev->state);
1257 if (ops->ndo_validate_addr)
1258 ret = ops->ndo_validate_addr(dev);
1260 if (!ret && ops->ndo_open)
1261 ret = ops->ndo_open(dev);
1263 netpoll_rx_enable(dev);
1266 clear_bit(__LINK_STATE_START, &dev->state);
1268 dev->flags |= IFF_UP;
1269 net_dmaengine_get();
1270 dev_set_rx_mode(dev);
1272 add_device_randomness(dev->dev_addr, dev->addr_len);
1279 * dev_open - prepare an interface for use.
1280 * @dev: device to open
1282 * Takes a device from down to up state. The device's private open
1283 * function is invoked and then the multicast lists are loaded. Finally
1284 * the device is moved into the up state and a %NETDEV_UP message is
1285 * sent to the netdev notifier chain.
1287 * Calling this function on an active interface is a nop. On a failure
1288 * a negative errno code is returned.
1290 int dev_open(struct net_device *dev)
1294 if (dev->flags & IFF_UP)
1297 ret = __dev_open(dev);
1301 rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP|IFF_RUNNING, GFP_KERNEL);
1302 call_netdevice_notifiers(NETDEV_UP, dev);
1306 EXPORT_SYMBOL(dev_open);
1308 static int __dev_close_many(struct list_head *head)
1310 struct net_device *dev;
1315 list_for_each_entry(dev, head, close_list) {
1316 call_netdevice_notifiers(NETDEV_GOING_DOWN, dev);
1318 clear_bit(__LINK_STATE_START, &dev->state);
1320 /* Synchronize to scheduled poll. We cannot touch poll list, it
1321 * can be even on different cpu. So just clear netif_running().
1323 * dev->stop() will invoke napi_disable() on all of it's
1324 * napi_struct instances on this device.
1326 smp_mb__after_clear_bit(); /* Commit netif_running(). */
1329 dev_deactivate_many(head);
1331 list_for_each_entry(dev, head, close_list) {
1332 const struct net_device_ops *ops = dev->netdev_ops;
1335 * Call the device specific close. This cannot fail.
1336 * Only if device is UP
1338 * We allow it to be called even after a DETACH hot-plug
1344 dev->flags &= ~IFF_UP;
1345 net_dmaengine_put();
1351 static int __dev_close(struct net_device *dev)
1356 /* Temporarily disable netpoll until the interface is down */
1357 netpoll_rx_disable(dev);
1359 list_add(&dev->close_list, &single);
1360 retval = __dev_close_many(&single);
1363 netpoll_rx_enable(dev);
1367 static int dev_close_many(struct list_head *head)
1369 struct net_device *dev, *tmp;
1371 /* Remove the devices that don't need to be closed */
1372 list_for_each_entry_safe(dev, tmp, head, close_list)
1373 if (!(dev->flags & IFF_UP))
1374 list_del_init(&dev->close_list);
1376 __dev_close_many(head);
1378 list_for_each_entry_safe(dev, tmp, head, close_list) {
1379 rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP|IFF_RUNNING, GFP_KERNEL);
1380 call_netdevice_notifiers(NETDEV_DOWN, dev);
1381 list_del_init(&dev->close_list);
1388 * dev_close - shutdown an interface.
1389 * @dev: device to shutdown
1391 * This function moves an active device into down state. A
1392 * %NETDEV_GOING_DOWN is sent to the netdev notifier chain. The device
1393 * is then deactivated and finally a %NETDEV_DOWN is sent to the notifier
1396 int dev_close(struct net_device *dev)
1398 if (dev->flags & IFF_UP) {
1401 /* Block netpoll rx while the interface is going down */
1402 netpoll_rx_disable(dev);
1404 list_add(&dev->close_list, &single);
1405 dev_close_many(&single);
1408 netpoll_rx_enable(dev);
1412 EXPORT_SYMBOL(dev_close);
1416 * dev_disable_lro - disable Large Receive Offload on a device
1419 * Disable Large Receive Offload (LRO) on a net device. Must be
1420 * called under RTNL. This is needed if received packets may be
1421 * forwarded to another interface.
1423 void dev_disable_lro(struct net_device *dev)
1426 * If we're trying to disable lro on a vlan device
1427 * use the underlying physical device instead
1429 if (is_vlan_dev(dev))
1430 dev = vlan_dev_real_dev(dev);
1432 /* the same for macvlan devices */
1433 if (netif_is_macvlan(dev))
1434 dev = macvlan_dev_real_dev(dev);
1436 dev->wanted_features &= ~NETIF_F_LRO;
1437 netdev_update_features(dev);
1439 if (unlikely(dev->features & NETIF_F_LRO))
1440 netdev_WARN(dev, "failed to disable LRO!\n");
1442 EXPORT_SYMBOL(dev_disable_lro);
1444 static int call_netdevice_notifier(struct notifier_block *nb, unsigned long val,
1445 struct net_device *dev)
1447 struct netdev_notifier_info info;
1449 netdev_notifier_info_init(&info, dev);
1450 return nb->notifier_call(nb, val, &info);
1453 static int dev_boot_phase = 1;
1456 * register_netdevice_notifier - register a network notifier block
1459 * Register a notifier to be called when network device events occur.
1460 * The notifier passed is linked into the kernel structures and must
1461 * not be reused until it has been unregistered. A negative errno code
1462 * is returned on a failure.
1464 * When registered all registration and up events are replayed
1465 * to the new notifier to allow device to have a race free
1466 * view of the network device list.
1469 int register_netdevice_notifier(struct notifier_block *nb)
1471 struct net_device *dev;
1472 struct net_device *last;
1477 err = raw_notifier_chain_register(&netdev_chain, nb);
1483 for_each_netdev(net, dev) {
1484 err = call_netdevice_notifier(nb, NETDEV_REGISTER, dev);
1485 err = notifier_to_errno(err);
1489 if (!(dev->flags & IFF_UP))
1492 call_netdevice_notifier(nb, NETDEV_UP, dev);
1503 for_each_netdev(net, dev) {
1507 if (dev->flags & IFF_UP) {
1508 call_netdevice_notifier(nb, NETDEV_GOING_DOWN,
1510 call_netdevice_notifier(nb, NETDEV_DOWN, dev);
1512 call_netdevice_notifier(nb, NETDEV_UNREGISTER, dev);
1517 raw_notifier_chain_unregister(&netdev_chain, nb);
1520 EXPORT_SYMBOL(register_netdevice_notifier);
1523 * unregister_netdevice_notifier - unregister a network notifier block
1526 * Unregister a notifier previously registered by
1527 * register_netdevice_notifier(). The notifier is unlinked into the
1528 * kernel structures and may then be reused. A negative errno code
1529 * is returned on a failure.
1531 * After unregistering unregister and down device events are synthesized
1532 * for all devices on the device list to the removed notifier to remove
1533 * the need for special case cleanup code.
1536 int unregister_netdevice_notifier(struct notifier_block *nb)
1538 struct net_device *dev;
1543 err = raw_notifier_chain_unregister(&netdev_chain, nb);
1548 for_each_netdev(net, dev) {
1549 if (dev->flags & IFF_UP) {
1550 call_netdevice_notifier(nb, NETDEV_GOING_DOWN,
1552 call_netdevice_notifier(nb, NETDEV_DOWN, dev);
1554 call_netdevice_notifier(nb, NETDEV_UNREGISTER, dev);
1561 EXPORT_SYMBOL(unregister_netdevice_notifier);
1564 * call_netdevice_notifiers_info - call all network notifier blocks
1565 * @val: value passed unmodified to notifier function
1566 * @dev: net_device pointer passed unmodified to notifier function
1567 * @info: notifier information data
1569 * Call all network notifier blocks. Parameters and return value
1570 * are as for raw_notifier_call_chain().
1573 static int call_netdevice_notifiers_info(unsigned long val,
1574 struct net_device *dev,
1575 struct netdev_notifier_info *info)
1578 netdev_notifier_info_init(info, dev);
1579 return raw_notifier_call_chain(&netdev_chain, val, info);
1583 * call_netdevice_notifiers - call all network notifier blocks
1584 * @val: value passed unmodified to notifier function
1585 * @dev: net_device pointer passed unmodified to notifier function
1587 * Call all network notifier blocks. Parameters and return value
1588 * are as for raw_notifier_call_chain().
1591 int call_netdevice_notifiers(unsigned long val, struct net_device *dev)
1593 struct netdev_notifier_info info;
1595 return call_netdevice_notifiers_info(val, dev, &info);
1597 EXPORT_SYMBOL(call_netdevice_notifiers);
1599 static struct static_key netstamp_needed __read_mostly;
1600 #ifdef HAVE_JUMP_LABEL
1601 /* We are not allowed to call static_key_slow_dec() from irq context
1602 * If net_disable_timestamp() is called from irq context, defer the
1603 * static_key_slow_dec() calls.
1605 static atomic_t netstamp_needed_deferred;
1608 void net_enable_timestamp(void)
1610 #ifdef HAVE_JUMP_LABEL
1611 int deferred = atomic_xchg(&netstamp_needed_deferred, 0);
1615 static_key_slow_dec(&netstamp_needed);
1619 static_key_slow_inc(&netstamp_needed);
1621 EXPORT_SYMBOL(net_enable_timestamp);
1623 void net_disable_timestamp(void)
1625 #ifdef HAVE_JUMP_LABEL
1626 if (in_interrupt()) {
1627 atomic_inc(&netstamp_needed_deferred);
1631 static_key_slow_dec(&netstamp_needed);
1633 EXPORT_SYMBOL(net_disable_timestamp);
1635 static inline void net_timestamp_set(struct sk_buff *skb)
1637 skb->tstamp.tv64 = 0;
1638 if (static_key_false(&netstamp_needed))
1639 __net_timestamp(skb);
1642 #define net_timestamp_check(COND, SKB) \
1643 if (static_key_false(&netstamp_needed)) { \
1644 if ((COND) && !(SKB)->tstamp.tv64) \
1645 __net_timestamp(SKB); \
1648 static inline bool is_skb_forwardable(struct net_device *dev,
1649 struct sk_buff *skb)
1653 if (!(dev->flags & IFF_UP))
1656 len = dev->mtu + dev->hard_header_len + VLAN_HLEN;
1657 if (skb->len <= len)
1660 /* if TSO is enabled, we don't care about the length as the packet
1661 * could be forwarded without being segmented before
1663 if (skb_is_gso(skb))
1670 * dev_forward_skb - loopback an skb to another netif
1672 * @dev: destination network device
1673 * @skb: buffer to forward
1676 * NET_RX_SUCCESS (no congestion)
1677 * NET_RX_DROP (packet was dropped, but freed)
1679 * dev_forward_skb can be used for injecting an skb from the
1680 * start_xmit function of one device into the receive queue
1681 * of another device.
1683 * The receiving device may be in another namespace, so
1684 * we have to clear all information in the skb that could
1685 * impact namespace isolation.
1687 int dev_forward_skb(struct net_device *dev, struct sk_buff *skb)
1689 if (skb_shinfo(skb)->tx_flags & SKBTX_DEV_ZEROCOPY) {
1690 if (skb_copy_ubufs(skb, GFP_ATOMIC)) {
1691 atomic_long_inc(&dev->rx_dropped);
1697 if (unlikely(!is_skb_forwardable(dev, skb))) {
1698 atomic_long_inc(&dev->rx_dropped);
1703 skb_scrub_packet(skb, true);
1704 skb->protocol = eth_type_trans(skb, dev);
1706 return netif_rx_internal(skb);
1708 EXPORT_SYMBOL_GPL(dev_forward_skb);
1710 static inline int deliver_skb(struct sk_buff *skb,
1711 struct packet_type *pt_prev,
1712 struct net_device *orig_dev)
1714 if (unlikely(skb_orphan_frags(skb, GFP_ATOMIC)))
1716 atomic_inc(&skb->users);
1717 return pt_prev->func(skb, skb->dev, pt_prev, orig_dev);
1720 static inline bool skb_loop_sk(struct packet_type *ptype, struct sk_buff *skb)
1722 if (!ptype->af_packet_priv || !skb->sk)
1725 if (ptype->id_match)
1726 return ptype->id_match(ptype, skb->sk);
1727 else if ((struct sock *)ptype->af_packet_priv == skb->sk)
1734 * Support routine. Sends outgoing frames to any network
1735 * taps currently in use.
1738 static void dev_queue_xmit_nit(struct sk_buff *skb, struct net_device *dev)
1740 struct packet_type *ptype;
1741 struct sk_buff *skb2 = NULL;
1742 struct packet_type *pt_prev = NULL;
1745 list_for_each_entry_rcu(ptype, &ptype_all, list) {
1746 /* Never send packets back to the socket
1747 * they originated from - MvS (miquels@drinkel.ow.org)
1749 if ((ptype->dev == dev || !ptype->dev) &&
1750 (!skb_loop_sk(ptype, skb))) {
1752 deliver_skb(skb2, pt_prev, skb->dev);
1757 skb2 = skb_clone(skb, GFP_ATOMIC);
1761 net_timestamp_set(skb2);
1763 /* skb->nh should be correctly
1764 set by sender, so that the second statement is
1765 just protection against buggy protocols.
1767 skb_reset_mac_header(skb2);
1769 if (skb_network_header(skb2) < skb2->data ||
1770 skb_network_header(skb2) > skb_tail_pointer(skb2)) {
1771 net_crit_ratelimited("protocol %04x is buggy, dev %s\n",
1772 ntohs(skb2->protocol),
1774 skb_reset_network_header(skb2);
1777 skb2->transport_header = skb2->network_header;
1778 skb2->pkt_type = PACKET_OUTGOING;
1783 pt_prev->func(skb2, skb->dev, pt_prev, skb->dev);
1788 * netif_setup_tc - Handle tc mappings on real_num_tx_queues change
1789 * @dev: Network device
1790 * @txq: number of queues available
1792 * If real_num_tx_queues is changed the tc mappings may no longer be
1793 * valid. To resolve this verify the tc mapping remains valid and if
1794 * not NULL the mapping. With no priorities mapping to this
1795 * offset/count pair it will no longer be used. In the worst case TC0
1796 * is invalid nothing can be done so disable priority mappings. If is
1797 * expected that drivers will fix this mapping if they can before
1798 * calling netif_set_real_num_tx_queues.
1800 static void netif_setup_tc(struct net_device *dev, unsigned int txq)
1803 struct netdev_tc_txq *tc = &dev->tc_to_txq[0];
1805 /* If TC0 is invalidated disable TC mapping */
1806 if (tc->offset + tc->count > txq) {
1807 pr_warn("Number of in use tx queues changed invalidating tc mappings. Priority traffic classification disabled!\n");
1812 /* Invalidated prio to tc mappings set to TC0 */
1813 for (i = 1; i < TC_BITMASK + 1; i++) {
1814 int q = netdev_get_prio_tc_map(dev, i);
1816 tc = &dev->tc_to_txq[q];
1817 if (tc->offset + tc->count > txq) {
1818 pr_warn("Number of in use tx queues changed. Priority %i to tc mapping %i is no longer valid. Setting map to 0\n",
1820 netdev_set_prio_tc_map(dev, i, 0);
1826 static DEFINE_MUTEX(xps_map_mutex);
1827 #define xmap_dereference(P) \
1828 rcu_dereference_protected((P), lockdep_is_held(&xps_map_mutex))
1830 static struct xps_map *remove_xps_queue(struct xps_dev_maps *dev_maps,
1833 struct xps_map *map = NULL;
1837 map = xmap_dereference(dev_maps->cpu_map[cpu]);
1839 for (pos = 0; map && pos < map->len; pos++) {
1840 if (map->queues[pos] == index) {
1842 map->queues[pos] = map->queues[--map->len];
1844 RCU_INIT_POINTER(dev_maps->cpu_map[cpu], NULL);
1845 kfree_rcu(map, rcu);
1855 static void netif_reset_xps_queues_gt(struct net_device *dev, u16 index)
1857 struct xps_dev_maps *dev_maps;
1859 bool active = false;
1861 mutex_lock(&xps_map_mutex);
1862 dev_maps = xmap_dereference(dev->xps_maps);
1867 for_each_possible_cpu(cpu) {
1868 for (i = index; i < dev->num_tx_queues; i++) {
1869 if (!remove_xps_queue(dev_maps, cpu, i))
1872 if (i == dev->num_tx_queues)
1877 RCU_INIT_POINTER(dev->xps_maps, NULL);
1878 kfree_rcu(dev_maps, rcu);
1881 for (i = index; i < dev->num_tx_queues; i++)
1882 netdev_queue_numa_node_write(netdev_get_tx_queue(dev, i),
1886 mutex_unlock(&xps_map_mutex);
1889 static struct xps_map *expand_xps_map(struct xps_map *map,
1892 struct xps_map *new_map;
1893 int alloc_len = XPS_MIN_MAP_ALLOC;
1896 for (pos = 0; map && pos < map->len; pos++) {
1897 if (map->queues[pos] != index)
1902 /* Need to add queue to this CPU's existing map */
1904 if (pos < map->alloc_len)
1907 alloc_len = map->alloc_len * 2;
1910 /* Need to allocate new map to store queue on this CPU's map */
1911 new_map = kzalloc_node(XPS_MAP_SIZE(alloc_len), GFP_KERNEL,
1916 for (i = 0; i < pos; i++)
1917 new_map->queues[i] = map->queues[i];
1918 new_map->alloc_len = alloc_len;
1924 int netif_set_xps_queue(struct net_device *dev, const struct cpumask *mask,
1927 struct xps_dev_maps *dev_maps, *new_dev_maps = NULL;
1928 struct xps_map *map, *new_map;
1929 int maps_sz = max_t(unsigned int, XPS_DEV_MAPS_SIZE, L1_CACHE_BYTES);
1930 int cpu, numa_node_id = -2;
1931 bool active = false;
1933 mutex_lock(&xps_map_mutex);
1935 dev_maps = xmap_dereference(dev->xps_maps);
1937 /* allocate memory for queue storage */
1938 for_each_online_cpu(cpu) {
1939 if (!cpumask_test_cpu(cpu, mask))
1943 new_dev_maps = kzalloc(maps_sz, GFP_KERNEL);
1944 if (!new_dev_maps) {
1945 mutex_unlock(&xps_map_mutex);
1949 map = dev_maps ? xmap_dereference(dev_maps->cpu_map[cpu]) :
1952 map = expand_xps_map(map, cpu, index);
1956 RCU_INIT_POINTER(new_dev_maps->cpu_map[cpu], map);
1960 goto out_no_new_maps;
1962 for_each_possible_cpu(cpu) {
1963 if (cpumask_test_cpu(cpu, mask) && cpu_online(cpu)) {
1964 /* add queue to CPU maps */
1967 map = xmap_dereference(new_dev_maps->cpu_map[cpu]);
1968 while ((pos < map->len) && (map->queues[pos] != index))
1971 if (pos == map->len)
1972 map->queues[map->len++] = index;
1974 if (numa_node_id == -2)
1975 numa_node_id = cpu_to_node(cpu);
1976 else if (numa_node_id != cpu_to_node(cpu))
1979 } else if (dev_maps) {
1980 /* fill in the new device map from the old device map */
1981 map = xmap_dereference(dev_maps->cpu_map[cpu]);
1982 RCU_INIT_POINTER(new_dev_maps->cpu_map[cpu], map);
1987 rcu_assign_pointer(dev->xps_maps, new_dev_maps);
1989 /* Cleanup old maps */
1991 for_each_possible_cpu(cpu) {
1992 new_map = xmap_dereference(new_dev_maps->cpu_map[cpu]);
1993 map = xmap_dereference(dev_maps->cpu_map[cpu]);
1994 if (map && map != new_map)
1995 kfree_rcu(map, rcu);
1998 kfree_rcu(dev_maps, rcu);
2001 dev_maps = new_dev_maps;
2005 /* update Tx queue numa node */
2006 netdev_queue_numa_node_write(netdev_get_tx_queue(dev, index),
2007 (numa_node_id >= 0) ? numa_node_id :
2013 /* removes queue from unused CPUs */
2014 for_each_possible_cpu(cpu) {
2015 if (cpumask_test_cpu(cpu, mask) && cpu_online(cpu))
2018 if (remove_xps_queue(dev_maps, cpu, index))
2022 /* free map if not active */
2024 RCU_INIT_POINTER(dev->xps_maps, NULL);
2025 kfree_rcu(dev_maps, rcu);
2029 mutex_unlock(&xps_map_mutex);
2033 /* remove any maps that we added */
2034 for_each_possible_cpu(cpu) {
2035 new_map = xmap_dereference(new_dev_maps->cpu_map[cpu]);
2036 map = dev_maps ? xmap_dereference(dev_maps->cpu_map[cpu]) :
2038 if (new_map && new_map != map)
2042 mutex_unlock(&xps_map_mutex);
2044 kfree(new_dev_maps);
2047 EXPORT_SYMBOL(netif_set_xps_queue);
2051 * Routine to help set real_num_tx_queues. To avoid skbs mapped to queues
2052 * greater then real_num_tx_queues stale skbs on the qdisc must be flushed.
2054 int netif_set_real_num_tx_queues(struct net_device *dev, unsigned int txq)
2058 if (txq < 1 || txq > dev->num_tx_queues)
2061 if (dev->reg_state == NETREG_REGISTERED ||
2062 dev->reg_state == NETREG_UNREGISTERING) {
2065 rc = netdev_queue_update_kobjects(dev, dev->real_num_tx_queues,
2071 netif_setup_tc(dev, txq);
2073 if (txq < dev->real_num_tx_queues) {
2074 qdisc_reset_all_tx_gt(dev, txq);
2076 netif_reset_xps_queues_gt(dev, txq);
2081 dev->real_num_tx_queues = txq;
2084 EXPORT_SYMBOL(netif_set_real_num_tx_queues);
2088 * netif_set_real_num_rx_queues - set actual number of RX queues used
2089 * @dev: Network device
2090 * @rxq: Actual number of RX queues
2092 * This must be called either with the rtnl_lock held or before
2093 * registration of the net device. Returns 0 on success, or a
2094 * negative error code. If called before registration, it always
2097 int netif_set_real_num_rx_queues(struct net_device *dev, unsigned int rxq)
2101 if (rxq < 1 || rxq > dev->num_rx_queues)
2104 if (dev->reg_state == NETREG_REGISTERED) {
2107 rc = net_rx_queue_update_kobjects(dev, dev->real_num_rx_queues,
2113 dev->real_num_rx_queues = rxq;
2116 EXPORT_SYMBOL(netif_set_real_num_rx_queues);
2120 * netif_get_num_default_rss_queues - default number of RSS queues
2122 * This routine should set an upper limit on the number of RSS queues
2123 * used by default by multiqueue devices.
2125 int netif_get_num_default_rss_queues(void)
2127 return min_t(int, DEFAULT_MAX_NUM_RSS_QUEUES, num_online_cpus());
2129 EXPORT_SYMBOL(netif_get_num_default_rss_queues);
2131 static inline void __netif_reschedule(struct Qdisc *q)
2133 struct softnet_data *sd;
2134 unsigned long flags;
2136 local_irq_save(flags);
2137 sd = &__get_cpu_var(softnet_data);
2138 q->next_sched = NULL;
2139 *sd->output_queue_tailp = q;
2140 sd->output_queue_tailp = &q->next_sched;
2141 raise_softirq_irqoff(NET_TX_SOFTIRQ);
2142 local_irq_restore(flags);
2145 void __netif_schedule(struct Qdisc *q)
2147 if (!test_and_set_bit(__QDISC_STATE_SCHED, &q->state))
2148 __netif_reschedule(q);
2150 EXPORT_SYMBOL(__netif_schedule);
2152 struct dev_kfree_skb_cb {
2153 enum skb_free_reason reason;
2156 static struct dev_kfree_skb_cb *get_kfree_skb_cb(const struct sk_buff *skb)
2158 return (struct dev_kfree_skb_cb *)skb->cb;
2161 void __dev_kfree_skb_irq(struct sk_buff *skb, enum skb_free_reason reason)
2163 unsigned long flags;
2165 if (likely(atomic_read(&skb->users) == 1)) {
2167 atomic_set(&skb->users, 0);
2168 } else if (likely(!atomic_dec_and_test(&skb->users))) {
2171 get_kfree_skb_cb(skb)->reason = reason;
2172 local_irq_save(flags);
2173 skb->next = __this_cpu_read(softnet_data.completion_queue);
2174 __this_cpu_write(softnet_data.completion_queue, skb);
2175 raise_softirq_irqoff(NET_TX_SOFTIRQ);
2176 local_irq_restore(flags);
2178 EXPORT_SYMBOL(__dev_kfree_skb_irq);
2180 void __dev_kfree_skb_any(struct sk_buff *skb, enum skb_free_reason reason)
2182 if (in_irq() || irqs_disabled())
2183 __dev_kfree_skb_irq(skb, reason);
2187 EXPORT_SYMBOL(__dev_kfree_skb_any);
2191 * netif_device_detach - mark device as removed
2192 * @dev: network device
2194 * Mark device as removed from system and therefore no longer available.
2196 void netif_device_detach(struct net_device *dev)
2198 if (test_and_clear_bit(__LINK_STATE_PRESENT, &dev->state) &&
2199 netif_running(dev)) {
2200 netif_tx_stop_all_queues(dev);
2203 EXPORT_SYMBOL(netif_device_detach);
2206 * netif_device_attach - mark device as attached
2207 * @dev: network device
2209 * Mark device as attached from system and restart if needed.
2211 void netif_device_attach(struct net_device *dev)
2213 if (!test_and_set_bit(__LINK_STATE_PRESENT, &dev->state) &&
2214 netif_running(dev)) {
2215 netif_tx_wake_all_queues(dev);
2216 __netdev_watchdog_up(dev);
2219 EXPORT_SYMBOL(netif_device_attach);
2221 static void skb_warn_bad_offload(const struct sk_buff *skb)
2223 static const netdev_features_t null_features = 0;
2224 struct net_device *dev = skb->dev;
2225 const char *driver = "";
2227 if (!net_ratelimit())
2230 if (dev && dev->dev.parent)
2231 driver = dev_driver_string(dev->dev.parent);
2233 WARN(1, "%s: caps=(%pNF, %pNF) len=%d data_len=%d gso_size=%d "
2234 "gso_type=%d ip_summed=%d\n",
2235 driver, dev ? &dev->features : &null_features,
2236 skb->sk ? &skb->sk->sk_route_caps : &null_features,
2237 skb->len, skb->data_len, skb_shinfo(skb)->gso_size,
2238 skb_shinfo(skb)->gso_type, skb->ip_summed);
2242 * Invalidate hardware checksum when packet is to be mangled, and
2243 * complete checksum manually on outgoing path.
2245 int skb_checksum_help(struct sk_buff *skb)
2248 int ret = 0, offset;
2250 if (skb->ip_summed == CHECKSUM_COMPLETE)
2251 goto out_set_summed;
2253 if (unlikely(skb_shinfo(skb)->gso_size)) {
2254 skb_warn_bad_offload(skb);
2258 /* Before computing a checksum, we should make sure no frag could
2259 * be modified by an external entity : checksum could be wrong.
2261 if (skb_has_shared_frag(skb)) {
2262 ret = __skb_linearize(skb);
2267 offset = skb_checksum_start_offset(skb);
2268 BUG_ON(offset >= skb_headlen(skb));
2269 csum = skb_checksum(skb, offset, skb->len - offset, 0);
2271 offset += skb->csum_offset;
2272 BUG_ON(offset + sizeof(__sum16) > skb_headlen(skb));
2274 if (skb_cloned(skb) &&
2275 !skb_clone_writable(skb, offset + sizeof(__sum16))) {
2276 ret = pskb_expand_head(skb, 0, 0, GFP_ATOMIC);
2281 *(__sum16 *)(skb->data + offset) = csum_fold(csum);
2283 skb->ip_summed = CHECKSUM_NONE;
2287 EXPORT_SYMBOL(skb_checksum_help);
2289 __be16 skb_network_protocol(struct sk_buff *skb)
2291 __be16 type = skb->protocol;
2292 int vlan_depth = ETH_HLEN;
2294 /* Tunnel gso handlers can set protocol to ethernet. */
2295 if (type == htons(ETH_P_TEB)) {
2298 if (unlikely(!pskb_may_pull(skb, sizeof(struct ethhdr))))
2301 eth = (struct ethhdr *)skb_mac_header(skb);
2302 type = eth->h_proto;
2305 while (type == htons(ETH_P_8021Q) || type == htons(ETH_P_8021AD)) {
2306 struct vlan_hdr *vh;
2308 if (unlikely(!pskb_may_pull(skb, vlan_depth + VLAN_HLEN)))
2311 vh = (struct vlan_hdr *)(skb->data + vlan_depth);
2312 type = vh->h_vlan_encapsulated_proto;
2313 vlan_depth += VLAN_HLEN;
2320 * skb_mac_gso_segment - mac layer segmentation handler.
2321 * @skb: buffer to segment
2322 * @features: features for the output path (see dev->features)
2324 struct sk_buff *skb_mac_gso_segment(struct sk_buff *skb,
2325 netdev_features_t features)
2327 struct sk_buff *segs = ERR_PTR(-EPROTONOSUPPORT);
2328 struct packet_offload *ptype;
2329 __be16 type = skb_network_protocol(skb);
2331 if (unlikely(!type))
2332 return ERR_PTR(-EINVAL);
2334 __skb_pull(skb, skb->mac_len);
2337 list_for_each_entry_rcu(ptype, &offload_base, list) {
2338 if (ptype->type == type && ptype->callbacks.gso_segment) {
2339 if (unlikely(skb->ip_summed != CHECKSUM_PARTIAL)) {
2342 err = ptype->callbacks.gso_send_check(skb);
2343 segs = ERR_PTR(err);
2344 if (err || skb_gso_ok(skb, features))
2346 __skb_push(skb, (skb->data -
2347 skb_network_header(skb)));
2349 segs = ptype->callbacks.gso_segment(skb, features);
2355 __skb_push(skb, skb->data - skb_mac_header(skb));
2359 EXPORT_SYMBOL(skb_mac_gso_segment);
2362 /* openvswitch calls this on rx path, so we need a different check.
2364 static inline bool skb_needs_check(struct sk_buff *skb, bool tx_path)
2367 return skb->ip_summed != CHECKSUM_PARTIAL;
2369 return skb->ip_summed == CHECKSUM_NONE;
2373 * __skb_gso_segment - Perform segmentation on skb.
2374 * @skb: buffer to segment
2375 * @features: features for the output path (see dev->features)
2376 * @tx_path: whether it is called in TX path
2378 * This function segments the given skb and returns a list of segments.
2380 * It may return NULL if the skb requires no segmentation. This is
2381 * only possible when GSO is used for verifying header integrity.
2383 struct sk_buff *__skb_gso_segment(struct sk_buff *skb,
2384 netdev_features_t features, bool tx_path)
2386 if (unlikely(skb_needs_check(skb, tx_path))) {
2389 skb_warn_bad_offload(skb);
2391 if (skb_header_cloned(skb) &&
2392 (err = pskb_expand_head(skb, 0, 0, GFP_ATOMIC)))
2393 return ERR_PTR(err);
2396 SKB_GSO_CB(skb)->mac_offset = skb_headroom(skb);
2397 SKB_GSO_CB(skb)->encap_level = 0;
2399 skb_reset_mac_header(skb);
2400 skb_reset_mac_len(skb);
2402 return skb_mac_gso_segment(skb, features);
2404 EXPORT_SYMBOL(__skb_gso_segment);
2406 /* Take action when hardware reception checksum errors are detected. */
2408 void netdev_rx_csum_fault(struct net_device *dev)
2410 if (net_ratelimit()) {
2411 pr_err("%s: hw csum failure\n", dev ? dev->name : "<unknown>");
2415 EXPORT_SYMBOL(netdev_rx_csum_fault);
2418 /* Actually, we should eliminate this check as soon as we know, that:
2419 * 1. IOMMU is present and allows to map all the memory.
2420 * 2. No high memory really exists on this machine.
2423 static int illegal_highdma(struct net_device *dev, struct sk_buff *skb)
2425 #ifdef CONFIG_HIGHMEM
2427 if (!(dev->features & NETIF_F_HIGHDMA)) {
2428 for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
2429 skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
2430 if (PageHighMem(skb_frag_page(frag)))
2435 if (PCI_DMA_BUS_IS_PHYS) {
2436 struct device *pdev = dev->dev.parent;
2440 for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
2441 skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
2442 dma_addr_t addr = page_to_phys(skb_frag_page(frag));
2443 if (!pdev->dma_mask || addr + PAGE_SIZE - 1 > *pdev->dma_mask)
2452 void (*destructor)(struct sk_buff *skb);
2455 #define DEV_GSO_CB(skb) ((struct dev_gso_cb *)(skb)->cb)
2457 static void dev_gso_skb_destructor(struct sk_buff *skb)
2459 struct dev_gso_cb *cb;
2461 kfree_skb_list(skb->next);
2464 cb = DEV_GSO_CB(skb);
2466 cb->destructor(skb);
2470 * dev_gso_segment - Perform emulated hardware segmentation on skb.
2471 * @skb: buffer to segment
2472 * @features: device features as applicable to this skb
2474 * This function segments the given skb and stores the list of segments
2477 static int dev_gso_segment(struct sk_buff *skb, netdev_features_t features)
2479 struct sk_buff *segs;
2481 segs = skb_gso_segment(skb, features);
2483 /* Verifying header integrity only. */
2488 return PTR_ERR(segs);
2491 DEV_GSO_CB(skb)->destructor = skb->destructor;
2492 skb->destructor = dev_gso_skb_destructor;
2497 static netdev_features_t harmonize_features(struct sk_buff *skb,
2498 netdev_features_t features)
2500 if (skb->ip_summed != CHECKSUM_NONE &&
2501 !can_checksum_protocol(features, skb_network_protocol(skb))) {
2502 features &= ~NETIF_F_ALL_CSUM;
2503 } else if (illegal_highdma(skb->dev, skb)) {
2504 features &= ~NETIF_F_SG;
2510 netdev_features_t netif_skb_features(struct sk_buff *skb)
2512 __be16 protocol = skb->protocol;
2513 netdev_features_t features = skb->dev->features;
2515 if (skb_shinfo(skb)->gso_segs > skb->dev->gso_max_segs)
2516 features &= ~NETIF_F_GSO_MASK;
2518 if (protocol == htons(ETH_P_8021Q) || protocol == htons(ETH_P_8021AD)) {
2519 struct vlan_ethhdr *veh = (struct vlan_ethhdr *)skb->data;
2520 protocol = veh->h_vlan_encapsulated_proto;
2521 } else if (!vlan_tx_tag_present(skb)) {
2522 return harmonize_features(skb, features);
2525 features &= (skb->dev->vlan_features | NETIF_F_HW_VLAN_CTAG_TX |
2526 NETIF_F_HW_VLAN_STAG_TX);
2528 if (protocol == htons(ETH_P_8021Q) || protocol == htons(ETH_P_8021AD))
2529 features &= NETIF_F_SG | NETIF_F_HIGHDMA | NETIF_F_FRAGLIST |
2530 NETIF_F_GEN_CSUM | NETIF_F_HW_VLAN_CTAG_TX |
2531 NETIF_F_HW_VLAN_STAG_TX;
2533 return harmonize_features(skb, features);
2535 EXPORT_SYMBOL(netif_skb_features);
2537 int dev_hard_start_xmit(struct sk_buff *skb, struct net_device *dev,
2538 struct netdev_queue *txq)
2540 const struct net_device_ops *ops = dev->netdev_ops;
2541 int rc = NETDEV_TX_OK;
2542 unsigned int skb_len;
2544 if (likely(!skb->next)) {
2545 netdev_features_t features;
2548 * If device doesn't need skb->dst, release it right now while
2549 * its hot in this cpu cache
2551 if (dev->priv_flags & IFF_XMIT_DST_RELEASE)
2554 features = netif_skb_features(skb);
2556 if (vlan_tx_tag_present(skb) &&
2557 !vlan_hw_offload_capable(features, skb->vlan_proto)) {
2558 skb = __vlan_put_tag(skb, skb->vlan_proto,
2559 vlan_tx_tag_get(skb));
2566 /* If encapsulation offload request, verify we are testing
2567 * hardware encapsulation features instead of standard
2568 * features for the netdev
2570 if (skb->encapsulation)
2571 features &= dev->hw_enc_features;
2573 if (netif_needs_gso(skb, features)) {
2574 if (unlikely(dev_gso_segment(skb, features)))
2579 if (skb_needs_linearize(skb, features) &&
2580 __skb_linearize(skb))
2583 /* If packet is not checksummed and device does not
2584 * support checksumming for this protocol, complete
2585 * checksumming here.
2587 if (skb->ip_summed == CHECKSUM_PARTIAL) {
2588 if (skb->encapsulation)
2589 skb_set_inner_transport_header(skb,
2590 skb_checksum_start_offset(skb));
2592 skb_set_transport_header(skb,
2593 skb_checksum_start_offset(skb));
2594 if (!(features & NETIF_F_ALL_CSUM) &&
2595 skb_checksum_help(skb))
2600 if (!list_empty(&ptype_all))
2601 dev_queue_xmit_nit(skb, dev);
2604 trace_net_dev_start_xmit(skb, dev);
2605 rc = ops->ndo_start_xmit(skb, dev);
2606 trace_net_dev_xmit(skb, rc, dev, skb_len);
2607 if (rc == NETDEV_TX_OK)
2608 txq_trans_update(txq);
2614 struct sk_buff *nskb = skb->next;
2616 skb->next = nskb->next;
2619 if (!list_empty(&ptype_all))
2620 dev_queue_xmit_nit(nskb, dev);
2622 skb_len = nskb->len;
2623 trace_net_dev_start_xmit(nskb, dev);
2624 rc = ops->ndo_start_xmit(nskb, dev);
2625 trace_net_dev_xmit(nskb, rc, dev, skb_len);
2626 if (unlikely(rc != NETDEV_TX_OK)) {
2627 if (rc & ~NETDEV_TX_MASK)
2628 goto out_kfree_gso_skb;
2629 nskb->next = skb->next;
2633 txq_trans_update(txq);
2634 if (unlikely(netif_xmit_stopped(txq) && skb->next))
2635 return NETDEV_TX_BUSY;
2636 } while (skb->next);
2639 if (likely(skb->next == NULL)) {
2640 skb->destructor = DEV_GSO_CB(skb)->destructor;
2649 EXPORT_SYMBOL_GPL(dev_hard_start_xmit);
2651 static void qdisc_pkt_len_init(struct sk_buff *skb)
2653 const struct skb_shared_info *shinfo = skb_shinfo(skb);
2655 qdisc_skb_cb(skb)->pkt_len = skb->len;
2657 /* To get more precise estimation of bytes sent on wire,
2658 * we add to pkt_len the headers size of all segments
2660 if (shinfo->gso_size) {
2661 unsigned int hdr_len;
2662 u16 gso_segs = shinfo->gso_segs;
2664 /* mac layer + network layer */
2665 hdr_len = skb_transport_header(skb) - skb_mac_header(skb);
2667 /* + transport layer */
2668 if (likely(shinfo->gso_type & (SKB_GSO_TCPV4 | SKB_GSO_TCPV6)))
2669 hdr_len += tcp_hdrlen(skb);
2671 hdr_len += sizeof(struct udphdr);
2673 if (shinfo->gso_type & SKB_GSO_DODGY)
2674 gso_segs = DIV_ROUND_UP(skb->len - hdr_len,
2677 qdisc_skb_cb(skb)->pkt_len += (gso_segs - 1) * hdr_len;
2681 static inline int __dev_xmit_skb(struct sk_buff *skb, struct Qdisc *q,
2682 struct net_device *dev,
2683 struct netdev_queue *txq)
2685 spinlock_t *root_lock = qdisc_lock(q);
2689 qdisc_pkt_len_init(skb);
2690 qdisc_calculate_pkt_len(skb, q);
2692 * Heuristic to force contended enqueues to serialize on a
2693 * separate lock before trying to get qdisc main lock.
2694 * This permits __QDISC_STATE_RUNNING owner to get the lock more often
2695 * and dequeue packets faster.
2697 contended = qdisc_is_running(q);
2698 if (unlikely(contended))
2699 spin_lock(&q->busylock);
2701 spin_lock(root_lock);
2702 if (unlikely(test_bit(__QDISC_STATE_DEACTIVATED, &q->state))) {
2705 } else if ((q->flags & TCQ_F_CAN_BYPASS) && !qdisc_qlen(q) &&
2706 qdisc_run_begin(q)) {
2708 * This is a work-conserving queue; there are no old skbs
2709 * waiting to be sent out; and the qdisc is not running -
2710 * xmit the skb directly.
2712 if (!(dev->priv_flags & IFF_XMIT_DST_RELEASE))
2715 qdisc_bstats_update(q, skb);
2717 if (sch_direct_xmit(skb, q, dev, txq, root_lock)) {
2718 if (unlikely(contended)) {
2719 spin_unlock(&q->busylock);
2726 rc = NET_XMIT_SUCCESS;
2729 rc = q->enqueue(skb, q) & NET_XMIT_MASK;
2730 if (qdisc_run_begin(q)) {
2731 if (unlikely(contended)) {
2732 spin_unlock(&q->busylock);
2738 spin_unlock(root_lock);
2739 if (unlikely(contended))
2740 spin_unlock(&q->busylock);
2744 #if IS_ENABLED(CONFIG_CGROUP_NET_PRIO)
2745 static void skb_update_prio(struct sk_buff *skb)
2747 struct netprio_map *map = rcu_dereference_bh(skb->dev->priomap);
2749 if (!skb->priority && skb->sk && map) {
2750 unsigned int prioidx = skb->sk->sk_cgrp_prioidx;
2752 if (prioidx < map->priomap_len)
2753 skb->priority = map->priomap[prioidx];
2757 #define skb_update_prio(skb)
2760 static DEFINE_PER_CPU(int, xmit_recursion);
2761 #define RECURSION_LIMIT 10
2764 * dev_loopback_xmit - loop back @skb
2765 * @skb: buffer to transmit
2767 int dev_loopback_xmit(struct sk_buff *skb)
2769 skb_reset_mac_header(skb);
2770 __skb_pull(skb, skb_network_offset(skb));
2771 skb->pkt_type = PACKET_LOOPBACK;
2772 skb->ip_summed = CHECKSUM_UNNECESSARY;
2773 WARN_ON(!skb_dst(skb));
2778 EXPORT_SYMBOL(dev_loopback_xmit);
2781 * dev_queue_xmit - transmit a buffer
2782 * @skb: buffer to transmit
2784 * Queue a buffer for transmission to a network device. The caller must
2785 * have set the device and priority and built the buffer before calling
2786 * this function. The function can be called from an interrupt.
2788 * A negative errno code is returned on a failure. A success does not
2789 * guarantee the frame will be transmitted as it may be dropped due
2790 * to congestion or traffic shaping.
2792 * -----------------------------------------------------------------------------------
2793 * I notice this method can also return errors from the queue disciplines,
2794 * including NET_XMIT_DROP, which is a positive value. So, errors can also
2797 * Regardless of the return value, the skb is consumed, so it is currently
2798 * difficult to retry a send to this method. (You can bump the ref count
2799 * before sending to hold a reference for retry if you are careful.)
2801 * When calling this method, interrupts MUST be enabled. This is because
2802 * the BH enable code must have IRQs enabled so that it will not deadlock.
2805 int __dev_queue_xmit(struct sk_buff *skb, void *accel_priv)
2807 struct net_device *dev = skb->dev;
2808 struct netdev_queue *txq;
2812 skb_reset_mac_header(skb);
2814 /* Disable soft irqs for various locks below. Also
2815 * stops preemption for RCU.
2819 skb_update_prio(skb);
2821 txq = netdev_pick_tx(dev, skb, accel_priv);
2822 q = rcu_dereference_bh(txq->qdisc);
2824 #ifdef CONFIG_NET_CLS_ACT
2825 skb->tc_verd = SET_TC_AT(skb->tc_verd, AT_EGRESS);
2827 trace_net_dev_queue(skb);
2829 rc = __dev_xmit_skb(skb, q, dev, txq);
2833 /* The device has no queue. Common case for software devices:
2834 loopback, all the sorts of tunnels...
2836 Really, it is unlikely that netif_tx_lock protection is necessary
2837 here. (f.e. loopback and IP tunnels are clean ignoring statistics
2839 However, it is possible, that they rely on protection
2842 Check this and shot the lock. It is not prone from deadlocks.
2843 Either shot noqueue qdisc, it is even simpler 8)
2845 if (dev->flags & IFF_UP) {
2846 int cpu = smp_processor_id(); /* ok because BHs are off */
2848 if (txq->xmit_lock_owner != cpu) {
2850 if (__this_cpu_read(xmit_recursion) > RECURSION_LIMIT)
2851 goto recursion_alert;
2853 HARD_TX_LOCK(dev, txq, cpu);
2855 if (!netif_xmit_stopped(txq)) {
2856 __this_cpu_inc(xmit_recursion);
2857 rc = dev_hard_start_xmit(skb, dev, txq);
2858 __this_cpu_dec(xmit_recursion);
2859 if (dev_xmit_complete(rc)) {
2860 HARD_TX_UNLOCK(dev, txq);
2864 HARD_TX_UNLOCK(dev, txq);
2865 net_crit_ratelimited("Virtual device %s asks to queue packet!\n",
2868 /* Recursion is detected! It is possible,
2872 net_crit_ratelimited("Dead loop on virtual device %s, fix it urgently!\n",
2878 rcu_read_unlock_bh();
2883 rcu_read_unlock_bh();
2887 int dev_queue_xmit(struct sk_buff *skb)
2889 return __dev_queue_xmit(skb, NULL);
2891 EXPORT_SYMBOL(dev_queue_xmit);
2893 int dev_queue_xmit_accel(struct sk_buff *skb, void *accel_priv)
2895 return __dev_queue_xmit(skb, accel_priv);
2897 EXPORT_SYMBOL(dev_queue_xmit_accel);
2900 /*=======================================================================
2902 =======================================================================*/
2904 int netdev_max_backlog __read_mostly = 1000;
2905 EXPORT_SYMBOL(netdev_max_backlog);
2907 int netdev_tstamp_prequeue __read_mostly = 1;
2908 int netdev_budget __read_mostly = 300;
2909 int weight_p __read_mostly = 64; /* old backlog weight */
2911 /* Called with irq disabled */
2912 static inline void ____napi_schedule(struct softnet_data *sd,
2913 struct napi_struct *napi)
2915 list_add_tail(&napi->poll_list, &sd->poll_list);
2916 __raise_softirq_irqoff(NET_RX_SOFTIRQ);
2921 /* One global table that all flow-based protocols share. */
2922 struct rps_sock_flow_table __rcu *rps_sock_flow_table __read_mostly;
2923 EXPORT_SYMBOL(rps_sock_flow_table);
2925 struct static_key rps_needed __read_mostly;
2927 static struct rps_dev_flow *
2928 set_rps_cpu(struct net_device *dev, struct sk_buff *skb,
2929 struct rps_dev_flow *rflow, u16 next_cpu)
2931 if (next_cpu != RPS_NO_CPU) {
2932 #ifdef CONFIG_RFS_ACCEL
2933 struct netdev_rx_queue *rxqueue;
2934 struct rps_dev_flow_table *flow_table;
2935 struct rps_dev_flow *old_rflow;
2940 /* Should we steer this flow to a different hardware queue? */
2941 if (!skb_rx_queue_recorded(skb) || !dev->rx_cpu_rmap ||
2942 !(dev->features & NETIF_F_NTUPLE))
2944 rxq_index = cpu_rmap_lookup_index(dev->rx_cpu_rmap, next_cpu);
2945 if (rxq_index == skb_get_rx_queue(skb))
2948 rxqueue = dev->_rx + rxq_index;
2949 flow_table = rcu_dereference(rxqueue->rps_flow_table);
2952 flow_id = skb->rxhash & flow_table->mask;
2953 rc = dev->netdev_ops->ndo_rx_flow_steer(dev, skb,
2954 rxq_index, flow_id);
2958 rflow = &flow_table->flows[flow_id];
2960 if (old_rflow->filter == rflow->filter)
2961 old_rflow->filter = RPS_NO_FILTER;
2965 per_cpu(softnet_data, next_cpu).input_queue_head;
2968 rflow->cpu = next_cpu;
2973 * get_rps_cpu is called from netif_receive_skb and returns the target
2974 * CPU from the RPS map of the receiving queue for a given skb.
2975 * rcu_read_lock must be held on entry.
2977 static int get_rps_cpu(struct net_device *dev, struct sk_buff *skb,
2978 struct rps_dev_flow **rflowp)
2980 struct netdev_rx_queue *rxqueue;
2981 struct rps_map *map;
2982 struct rps_dev_flow_table *flow_table;
2983 struct rps_sock_flow_table *sock_flow_table;
2987 if (skb_rx_queue_recorded(skb)) {
2988 u16 index = skb_get_rx_queue(skb);
2989 if (unlikely(index >= dev->real_num_rx_queues)) {
2990 WARN_ONCE(dev->real_num_rx_queues > 1,
2991 "%s received packet on queue %u, but number "
2992 "of RX queues is %u\n",
2993 dev->name, index, dev->real_num_rx_queues);
2996 rxqueue = dev->_rx + index;
3000 map = rcu_dereference(rxqueue->rps_map);
3002 if (map->len == 1 &&
3003 !rcu_access_pointer(rxqueue->rps_flow_table)) {
3004 tcpu = map->cpus[0];
3005 if (cpu_online(tcpu))
3009 } else if (!rcu_access_pointer(rxqueue->rps_flow_table)) {
3013 skb_reset_network_header(skb);
3014 if (!skb_get_hash(skb))
3017 flow_table = rcu_dereference(rxqueue->rps_flow_table);
3018 sock_flow_table = rcu_dereference(rps_sock_flow_table);
3019 if (flow_table && sock_flow_table) {
3021 struct rps_dev_flow *rflow;
3023 rflow = &flow_table->flows[skb->rxhash & flow_table->mask];
3026 next_cpu = sock_flow_table->ents[skb->rxhash &
3027 sock_flow_table->mask];
3030 * If the desired CPU (where last recvmsg was done) is
3031 * different from current CPU (one in the rx-queue flow
3032 * table entry), switch if one of the following holds:
3033 * - Current CPU is unset (equal to RPS_NO_CPU).
3034 * - Current CPU is offline.
3035 * - The current CPU's queue tail has advanced beyond the
3036 * last packet that was enqueued using this table entry.
3037 * This guarantees that all previous packets for the flow
3038 * have been dequeued, thus preserving in order delivery.
3040 if (unlikely(tcpu != next_cpu) &&
3041 (tcpu == RPS_NO_CPU || !cpu_online(tcpu) ||
3042 ((int)(per_cpu(softnet_data, tcpu).input_queue_head -
3043 rflow->last_qtail)) >= 0)) {
3045 rflow = set_rps_cpu(dev, skb, rflow, next_cpu);
3048 if (tcpu != RPS_NO_CPU && cpu_online(tcpu)) {
3056 tcpu = map->cpus[((u64) skb->rxhash * map->len) >> 32];
3058 if (cpu_online(tcpu)) {
3068 #ifdef CONFIG_RFS_ACCEL
3071 * rps_may_expire_flow - check whether an RFS hardware filter may be removed
3072 * @dev: Device on which the filter was set
3073 * @rxq_index: RX queue index
3074 * @flow_id: Flow ID passed to ndo_rx_flow_steer()
3075 * @filter_id: Filter ID returned by ndo_rx_flow_steer()
3077 * Drivers that implement ndo_rx_flow_steer() should periodically call
3078 * this function for each installed filter and remove the filters for
3079 * which it returns %true.
3081 bool rps_may_expire_flow(struct net_device *dev, u16 rxq_index,
3082 u32 flow_id, u16 filter_id)
3084 struct netdev_rx_queue *rxqueue = dev->_rx + rxq_index;
3085 struct rps_dev_flow_table *flow_table;
3086 struct rps_dev_flow *rflow;
3091 flow_table = rcu_dereference(rxqueue->rps_flow_table);
3092 if (flow_table && flow_id <= flow_table->mask) {
3093 rflow = &flow_table->flows[flow_id];
3094 cpu = ACCESS_ONCE(rflow->cpu);
3095 if (rflow->filter == filter_id && cpu != RPS_NO_CPU &&
3096 ((int)(per_cpu(softnet_data, cpu).input_queue_head -
3097 rflow->last_qtail) <
3098 (int)(10 * flow_table->mask)))
3104 EXPORT_SYMBOL(rps_may_expire_flow);
3106 #endif /* CONFIG_RFS_ACCEL */
3108 /* Called from hardirq (IPI) context */
3109 static void rps_trigger_softirq(void *data)
3111 struct softnet_data *sd = data;
3113 ____napi_schedule(sd, &sd->backlog);
3117 #endif /* CONFIG_RPS */
3120 * Check if this softnet_data structure is another cpu one
3121 * If yes, queue it to our IPI list and return 1
3124 static int rps_ipi_queued(struct softnet_data *sd)
3127 struct softnet_data *mysd = &__get_cpu_var(softnet_data);
3130 sd->rps_ipi_next = mysd->rps_ipi_list;
3131 mysd->rps_ipi_list = sd;
3133 __raise_softirq_irqoff(NET_RX_SOFTIRQ);
3136 #endif /* CONFIG_RPS */
3140 #ifdef CONFIG_NET_FLOW_LIMIT
3141 int netdev_flow_limit_table_len __read_mostly = (1 << 12);
3144 static bool skb_flow_limit(struct sk_buff *skb, unsigned int qlen)
3146 #ifdef CONFIG_NET_FLOW_LIMIT
3147 struct sd_flow_limit *fl;
3148 struct softnet_data *sd;
3149 unsigned int old_flow, new_flow;
3151 if (qlen < (netdev_max_backlog >> 1))
3154 sd = &__get_cpu_var(softnet_data);
3157 fl = rcu_dereference(sd->flow_limit);
3159 new_flow = skb_get_hash(skb) & (fl->num_buckets - 1);
3160 old_flow = fl->history[fl->history_head];
3161 fl->history[fl->history_head] = new_flow;
3164 fl->history_head &= FLOW_LIMIT_HISTORY - 1;
3166 if (likely(fl->buckets[old_flow]))
3167 fl->buckets[old_flow]--;
3169 if (++fl->buckets[new_flow] > (FLOW_LIMIT_HISTORY >> 1)) {
3181 * enqueue_to_backlog is called to queue an skb to a per CPU backlog
3182 * queue (may be a remote CPU queue).
3184 static int enqueue_to_backlog(struct sk_buff *skb, int cpu,
3185 unsigned int *qtail)
3187 struct softnet_data *sd;
3188 unsigned long flags;
3191 sd = &per_cpu(softnet_data, cpu);
3193 local_irq_save(flags);
3196 qlen = skb_queue_len(&sd->input_pkt_queue);
3197 if (qlen <= netdev_max_backlog && !skb_flow_limit(skb, qlen)) {
3198 if (skb_queue_len(&sd->input_pkt_queue)) {
3200 __skb_queue_tail(&sd->input_pkt_queue, skb);
3201 input_queue_tail_incr_save(sd, qtail);
3203 local_irq_restore(flags);
3204 return NET_RX_SUCCESS;
3207 /* Schedule NAPI for backlog device
3208 * We can use non atomic operation since we own the queue lock
3210 if (!__test_and_set_bit(NAPI_STATE_SCHED, &sd->backlog.state)) {
3211 if (!rps_ipi_queued(sd))
3212 ____napi_schedule(sd, &sd->backlog);
3220 local_irq_restore(flags);
3222 atomic_long_inc(&skb->dev->rx_dropped);
3227 static int netif_rx_internal(struct sk_buff *skb)
3231 /* if netpoll wants it, pretend we never saw it */
3232 if (netpoll_rx(skb))
3235 net_timestamp_check(netdev_tstamp_prequeue, skb);
3237 trace_netif_rx(skb);
3239 if (static_key_false(&rps_needed)) {
3240 struct rps_dev_flow voidflow, *rflow = &voidflow;
3246 cpu = get_rps_cpu(skb->dev, skb, &rflow);
3248 cpu = smp_processor_id();
3250 ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail);
3258 ret = enqueue_to_backlog(skb, get_cpu(), &qtail);
3265 * netif_rx - post buffer to the network code
3266 * @skb: buffer to post
3268 * This function receives a packet from a device driver and queues it for
3269 * the upper (protocol) levels to process. It always succeeds. The buffer
3270 * may be dropped during processing for congestion control or by the
3274 * NET_RX_SUCCESS (no congestion)
3275 * NET_RX_DROP (packet was dropped)
3279 int netif_rx(struct sk_buff *skb)
3281 trace_netif_rx_entry(skb);
3283 return netif_rx_internal(skb);
3285 EXPORT_SYMBOL(netif_rx);
3287 int netif_rx_ni(struct sk_buff *skb)
3291 trace_netif_rx_ni_entry(skb);
3294 err = netif_rx_internal(skb);
3295 if (local_softirq_pending())
3301 EXPORT_SYMBOL(netif_rx_ni);
3303 static void net_tx_action(struct softirq_action *h)
3305 struct softnet_data *sd = &__get_cpu_var(softnet_data);
3307 if (sd->completion_queue) {
3308 struct sk_buff *clist;
3310 local_irq_disable();
3311 clist = sd->completion_queue;
3312 sd->completion_queue = NULL;
3316 struct sk_buff *skb = clist;
3317 clist = clist->next;
3319 WARN_ON(atomic_read(&skb->users));
3320 if (likely(get_kfree_skb_cb(skb)->reason == SKB_REASON_CONSUMED))
3321 trace_consume_skb(skb);
3323 trace_kfree_skb(skb, net_tx_action);
3328 if (sd->output_queue) {
3331 local_irq_disable();
3332 head = sd->output_queue;
3333 sd->output_queue = NULL;
3334 sd->output_queue_tailp = &sd->output_queue;
3338 struct Qdisc *q = head;
3339 spinlock_t *root_lock;
3341 head = head->next_sched;
3343 root_lock = qdisc_lock(q);
3344 if (spin_trylock(root_lock)) {
3345 smp_mb__before_clear_bit();
3346 clear_bit(__QDISC_STATE_SCHED,
3349 spin_unlock(root_lock);
3351 if (!test_bit(__QDISC_STATE_DEACTIVATED,
3353 __netif_reschedule(q);
3355 smp_mb__before_clear_bit();
3356 clear_bit(__QDISC_STATE_SCHED,
3364 #if (defined(CONFIG_BRIDGE) || defined(CONFIG_BRIDGE_MODULE)) && \
3365 (defined(CONFIG_ATM_LANE) || defined(CONFIG_ATM_LANE_MODULE))
3366 /* This hook is defined here for ATM LANE */
3367 int (*br_fdb_test_addr_hook)(struct net_device *dev,
3368 unsigned char *addr) __read_mostly;
3369 EXPORT_SYMBOL_GPL(br_fdb_test_addr_hook);
3372 #ifdef CONFIG_NET_CLS_ACT
3373 /* TODO: Maybe we should just force sch_ingress to be compiled in
3374 * when CONFIG_NET_CLS_ACT is? otherwise some useless instructions
3375 * a compare and 2 stores extra right now if we dont have it on
3376 * but have CONFIG_NET_CLS_ACT
3377 * NOTE: This doesn't stop any functionality; if you dont have
3378 * the ingress scheduler, you just can't add policies on ingress.
3381 static int ing_filter(struct sk_buff *skb, struct netdev_queue *rxq)
3383 struct net_device *dev = skb->dev;
3384 u32 ttl = G_TC_RTTL(skb->tc_verd);
3385 int result = TC_ACT_OK;
3388 if (unlikely(MAX_RED_LOOP < ttl++)) {
3389 net_warn_ratelimited("Redir loop detected Dropping packet (%d->%d)\n",
3390 skb->skb_iif, dev->ifindex);
3394 skb->tc_verd = SET_TC_RTTL(skb->tc_verd, ttl);
3395 skb->tc_verd = SET_TC_AT(skb->tc_verd, AT_INGRESS);
3398 if (q != &noop_qdisc) {
3399 spin_lock(qdisc_lock(q));
3400 if (likely(!test_bit(__QDISC_STATE_DEACTIVATED, &q->state)))
3401 result = qdisc_enqueue_root(skb, q);
3402 spin_unlock(qdisc_lock(q));
3408 static inline struct sk_buff *handle_ing(struct sk_buff *skb,
3409 struct packet_type **pt_prev,
3410 int *ret, struct net_device *orig_dev)
3412 struct netdev_queue *rxq = rcu_dereference(skb->dev->ingress_queue);
3414 if (!rxq || rxq->qdisc == &noop_qdisc)
3418 *ret = deliver_skb(skb, *pt_prev, orig_dev);
3422 switch (ing_filter(skb, rxq)) {
3436 * netdev_rx_handler_register - register receive handler
3437 * @dev: device to register a handler for
3438 * @rx_handler: receive handler to register
3439 * @rx_handler_data: data pointer that is used by rx handler
3441 * Register a receive hander for a device. This handler will then be
3442 * called from __netif_receive_skb. A negative errno code is returned
3445 * The caller must hold the rtnl_mutex.
3447 * For a general description of rx_handler, see enum rx_handler_result.
3449 int netdev_rx_handler_register(struct net_device *dev,
3450 rx_handler_func_t *rx_handler,
3451 void *rx_handler_data)
3455 if (dev->rx_handler)
3458 /* Note: rx_handler_data must be set before rx_handler */
3459 rcu_assign_pointer(dev->rx_handler_data, rx_handler_data);
3460 rcu_assign_pointer(dev->rx_handler, rx_handler);
3464 EXPORT_SYMBOL_GPL(netdev_rx_handler_register);
3467 * netdev_rx_handler_unregister - unregister receive handler
3468 * @dev: device to unregister a handler from
3470 * Unregister a receive handler from a device.
3472 * The caller must hold the rtnl_mutex.
3474 void netdev_rx_handler_unregister(struct net_device *dev)
3478 RCU_INIT_POINTER(dev->rx_handler, NULL);
3479 /* a reader seeing a non NULL rx_handler in a rcu_read_lock()
3480 * section has a guarantee to see a non NULL rx_handler_data
3484 RCU_INIT_POINTER(dev->rx_handler_data, NULL);
3486 EXPORT_SYMBOL_GPL(netdev_rx_handler_unregister);
3489 * Limit the use of PFMEMALLOC reserves to those protocols that implement
3490 * the special handling of PFMEMALLOC skbs.
3492 static bool skb_pfmemalloc_protocol(struct sk_buff *skb)
3494 switch (skb->protocol) {
3495 case __constant_htons(ETH_P_ARP):
3496 case __constant_htons(ETH_P_IP):
3497 case __constant_htons(ETH_P_IPV6):
3498 case __constant_htons(ETH_P_8021Q):
3499 case __constant_htons(ETH_P_8021AD):
3506 static int __netif_receive_skb_core(struct sk_buff *skb, bool pfmemalloc)
3508 struct packet_type *ptype, *pt_prev;
3509 rx_handler_func_t *rx_handler;
3510 struct net_device *orig_dev;
3511 struct net_device *null_or_dev;
3512 bool deliver_exact = false;
3513 int ret = NET_RX_DROP;
3516 net_timestamp_check(!netdev_tstamp_prequeue, skb);
3518 trace_netif_receive_skb(skb);
3520 /* if we've gotten here through NAPI, check netpoll */
3521 if (netpoll_receive_skb(skb))
3524 orig_dev = skb->dev;
3526 skb_reset_network_header(skb);
3527 if (!skb_transport_header_was_set(skb))
3528 skb_reset_transport_header(skb);
3529 skb_reset_mac_len(skb);
3536 skb->skb_iif = skb->dev->ifindex;
3538 __this_cpu_inc(softnet_data.processed);
3540 if (skb->protocol == cpu_to_be16(ETH_P_8021Q) ||
3541 skb->protocol == cpu_to_be16(ETH_P_8021AD)) {
3542 skb = vlan_untag(skb);
3547 #ifdef CONFIG_NET_CLS_ACT
3548 if (skb->tc_verd & TC_NCLS) {
3549 skb->tc_verd = CLR_TC_NCLS(skb->tc_verd);
3557 list_for_each_entry_rcu(ptype, &ptype_all, list) {
3558 if (!ptype->dev || ptype->dev == skb->dev) {
3560 ret = deliver_skb(skb, pt_prev, orig_dev);
3566 #ifdef CONFIG_NET_CLS_ACT
3567 skb = handle_ing(skb, &pt_prev, &ret, orig_dev);
3573 if (pfmemalloc && !skb_pfmemalloc_protocol(skb))
3576 if (vlan_tx_tag_present(skb)) {
3578 ret = deliver_skb(skb, pt_prev, orig_dev);
3581 if (vlan_do_receive(&skb))
3583 else if (unlikely(!skb))
3587 rx_handler = rcu_dereference(skb->dev->rx_handler);
3590 ret = deliver_skb(skb, pt_prev, orig_dev);
3593 switch (rx_handler(&skb)) {
3594 case RX_HANDLER_CONSUMED:
3595 ret = NET_RX_SUCCESS;
3597 case RX_HANDLER_ANOTHER:
3599 case RX_HANDLER_EXACT:
3600 deliver_exact = true;
3601 case RX_HANDLER_PASS:
3608 if (unlikely(vlan_tx_tag_present(skb))) {
3609 if (vlan_tx_tag_get_id(skb))
3610 skb->pkt_type = PACKET_OTHERHOST;
3611 /* Note: we might in the future use prio bits
3612 * and set skb->priority like in vlan_do_receive()
3613 * For the time being, just ignore Priority Code Point
3618 /* deliver only exact match when indicated */
3619 null_or_dev = deliver_exact ? skb->dev : NULL;
3621 type = skb->protocol;
3622 list_for_each_entry_rcu(ptype,
3623 &ptype_base[ntohs(type) & PTYPE_HASH_MASK], list) {
3624 if (ptype->type == type &&
3625 (ptype->dev == null_or_dev || ptype->dev == skb->dev ||
3626 ptype->dev == orig_dev)) {
3628 ret = deliver_skb(skb, pt_prev, orig_dev);
3634 if (unlikely(skb_orphan_frags(skb, GFP_ATOMIC)))
3637 ret = pt_prev->func(skb, skb->dev, pt_prev, orig_dev);
3640 atomic_long_inc(&skb->dev->rx_dropped);
3642 /* Jamal, now you will not able to escape explaining
3643 * me how you were going to use this. :-)
3654 static int __netif_receive_skb(struct sk_buff *skb)
3658 if (sk_memalloc_socks() && skb_pfmemalloc(skb)) {
3659 unsigned long pflags = current->flags;
3662 * PFMEMALLOC skbs are special, they should
3663 * - be delivered to SOCK_MEMALLOC sockets only
3664 * - stay away from userspace
3665 * - have bounded memory usage
3667 * Use PF_MEMALLOC as this saves us from propagating the allocation
3668 * context down to all allocation sites.
3670 current->flags |= PF_MEMALLOC;
3671 ret = __netif_receive_skb_core(skb, true);
3672 tsk_restore_flags(current, pflags, PF_MEMALLOC);
3674 ret = __netif_receive_skb_core(skb, false);
3679 static int netif_receive_skb_internal(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);
3707 * netif_receive_skb - process receive buffer from network
3708 * @skb: buffer to process
3710 * netif_receive_skb() is the main receive data processing function.
3711 * It always succeeds. The buffer may be dropped during processing
3712 * for congestion control or by the protocol layers.
3714 * This function may only be called from softirq context and interrupts
3715 * should be enabled.
3717 * Return values (usually ignored):
3718 * NET_RX_SUCCESS: no congestion
3719 * NET_RX_DROP: packet was dropped
3721 int netif_receive_skb(struct sk_buff *skb)
3723 trace_netif_receive_skb_entry(skb);
3725 return netif_receive_skb_internal(skb);
3727 EXPORT_SYMBOL(netif_receive_skb);
3729 /* Network device is going away, flush any packets still pending
3730 * Called with irqs disabled.
3732 static void flush_backlog(void *arg)
3734 struct net_device *dev = arg;
3735 struct softnet_data *sd = &__get_cpu_var(softnet_data);
3736 struct sk_buff *skb, *tmp;
3739 skb_queue_walk_safe(&sd->input_pkt_queue, skb, tmp) {
3740 if (skb->dev == dev) {
3741 __skb_unlink(skb, &sd->input_pkt_queue);
3743 input_queue_head_incr(sd);
3748 skb_queue_walk_safe(&sd->process_queue, skb, tmp) {
3749 if (skb->dev == dev) {
3750 __skb_unlink(skb, &sd->process_queue);
3752 input_queue_head_incr(sd);
3757 static int napi_gro_complete(struct sk_buff *skb)
3759 struct packet_offload *ptype;
3760 __be16 type = skb->protocol;
3761 struct list_head *head = &offload_base;
3764 BUILD_BUG_ON(sizeof(struct napi_gro_cb) > sizeof(skb->cb));
3766 if (NAPI_GRO_CB(skb)->count == 1) {
3767 skb_shinfo(skb)->gso_size = 0;
3772 list_for_each_entry_rcu(ptype, head, list) {
3773 if (ptype->type != type || !ptype->callbacks.gro_complete)
3776 err = ptype->callbacks.gro_complete(skb, 0);
3782 WARN_ON(&ptype->list == head);
3784 return NET_RX_SUCCESS;
3788 return netif_receive_skb_internal(skb);
3791 /* napi->gro_list contains packets ordered by age.
3792 * youngest packets at the head of it.
3793 * Complete skbs in reverse order to reduce latencies.
3795 void napi_gro_flush(struct napi_struct *napi, bool flush_old)
3797 struct sk_buff *skb, *prev = NULL;
3799 /* scan list and build reverse chain */
3800 for (skb = napi->gro_list; skb != NULL; skb = skb->next) {
3805 for (skb = prev; skb; skb = prev) {
3808 if (flush_old && NAPI_GRO_CB(skb)->age == jiffies)
3812 napi_gro_complete(skb);
3816 napi->gro_list = NULL;
3818 EXPORT_SYMBOL(napi_gro_flush);
3820 static void gro_list_prepare(struct napi_struct *napi, struct sk_buff *skb)
3823 unsigned int maclen = skb->dev->hard_header_len;
3825 for (p = napi->gro_list; p; p = p->next) {
3826 unsigned long diffs;
3828 diffs = (unsigned long)p->dev ^ (unsigned long)skb->dev;
3829 diffs |= p->vlan_tci ^ skb->vlan_tci;
3830 if (maclen == ETH_HLEN)
3831 diffs |= compare_ether_header(skb_mac_header(p),
3832 skb_gro_mac_header(skb));
3834 diffs = memcmp(skb_mac_header(p),
3835 skb_gro_mac_header(skb),
3837 NAPI_GRO_CB(p)->same_flow = !diffs;
3838 NAPI_GRO_CB(p)->flush = 0;
3842 static void skb_gro_reset_offset(struct sk_buff *skb)
3844 const struct skb_shared_info *pinfo = skb_shinfo(skb);
3845 const skb_frag_t *frag0 = &pinfo->frags[0];
3847 NAPI_GRO_CB(skb)->data_offset = 0;
3848 NAPI_GRO_CB(skb)->frag0 = NULL;
3849 NAPI_GRO_CB(skb)->frag0_len = 0;
3851 if (skb_mac_header(skb) == skb_tail_pointer(skb) &&
3853 !PageHighMem(skb_frag_page(frag0))) {
3854 NAPI_GRO_CB(skb)->frag0 = skb_frag_address(frag0);
3855 NAPI_GRO_CB(skb)->frag0_len = skb_frag_size(frag0);
3859 static enum gro_result dev_gro_receive(struct napi_struct *napi, struct sk_buff *skb)
3861 struct sk_buff **pp = NULL;
3862 struct packet_offload *ptype;
3863 __be16 type = skb->protocol;
3864 struct list_head *head = &offload_base;
3866 enum gro_result ret;
3868 if (!(skb->dev->features & NETIF_F_GRO) || netpoll_rx_on(skb))
3871 if (skb_is_gso(skb) || skb_has_frag_list(skb))
3874 skb_gro_reset_offset(skb);
3875 gro_list_prepare(napi, skb);
3876 NAPI_GRO_CB(skb)->csum = skb->csum; /* Needed for CHECKSUM_COMPLETE */
3879 list_for_each_entry_rcu(ptype, head, list) {
3880 if (ptype->type != type || !ptype->callbacks.gro_receive)
3883 skb_set_network_header(skb, skb_gro_offset(skb));
3884 skb_reset_mac_len(skb);
3885 NAPI_GRO_CB(skb)->same_flow = 0;
3886 NAPI_GRO_CB(skb)->flush = 0;
3887 NAPI_GRO_CB(skb)->free = 0;
3889 pp = ptype->callbacks.gro_receive(&napi->gro_list, skb);
3894 if (&ptype->list == head)
3897 same_flow = NAPI_GRO_CB(skb)->same_flow;
3898 ret = NAPI_GRO_CB(skb)->free ? GRO_MERGED_FREE : GRO_MERGED;
3901 struct sk_buff *nskb = *pp;
3905 napi_gro_complete(nskb);
3912 if (NAPI_GRO_CB(skb)->flush)
3915 if (unlikely(napi->gro_count >= MAX_GRO_SKBS)) {
3916 struct sk_buff *nskb = napi->gro_list;
3918 /* locate the end of the list to select the 'oldest' flow */
3919 while (nskb->next) {
3925 napi_gro_complete(nskb);
3929 NAPI_GRO_CB(skb)->count = 1;
3930 NAPI_GRO_CB(skb)->age = jiffies;
3931 skb_shinfo(skb)->gso_size = skb_gro_len(skb);
3932 skb->next = napi->gro_list;
3933 napi->gro_list = skb;
3937 if (skb_headlen(skb) < skb_gro_offset(skb)) {
3938 int grow = skb_gro_offset(skb) - skb_headlen(skb);
3940 BUG_ON(skb->end - skb->tail < grow);
3942 memcpy(skb_tail_pointer(skb), NAPI_GRO_CB(skb)->frag0, grow);
3945 skb->data_len -= grow;
3947 skb_shinfo(skb)->frags[0].page_offset += grow;
3948 skb_frag_size_sub(&skb_shinfo(skb)->frags[0], grow);
3950 if (unlikely(!skb_frag_size(&skb_shinfo(skb)->frags[0]))) {
3951 skb_frag_unref(skb, 0);
3952 memmove(skb_shinfo(skb)->frags,
3953 skb_shinfo(skb)->frags + 1,
3954 --skb_shinfo(skb)->nr_frags * sizeof(skb_frag_t));
3966 struct packet_offload *gro_find_receive_by_type(__be16 type)
3968 struct list_head *offload_head = &offload_base;
3969 struct packet_offload *ptype;
3971 list_for_each_entry_rcu(ptype, offload_head, list) {
3972 if (ptype->type != type || !ptype->callbacks.gro_receive)
3979 struct packet_offload *gro_find_complete_by_type(__be16 type)
3981 struct list_head *offload_head = &offload_base;
3982 struct packet_offload *ptype;
3984 list_for_each_entry_rcu(ptype, offload_head, list) {
3985 if (ptype->type != type || !ptype->callbacks.gro_complete)
3992 static gro_result_t napi_skb_finish(gro_result_t ret, struct sk_buff *skb)
3996 if (netif_receive_skb_internal(skb))
4004 case GRO_MERGED_FREE:
4005 if (NAPI_GRO_CB(skb)->free == NAPI_GRO_FREE_STOLEN_HEAD)
4006 kmem_cache_free(skbuff_head_cache, skb);
4019 gro_result_t napi_gro_receive(struct napi_struct *napi, struct sk_buff *skb)
4021 trace_napi_gro_receive_entry(skb);
4023 return napi_skb_finish(dev_gro_receive(napi, skb), skb);
4025 EXPORT_SYMBOL(napi_gro_receive);
4027 static void napi_reuse_skb(struct napi_struct *napi, struct sk_buff *skb)
4029 __skb_pull(skb, skb_headlen(skb));
4030 /* restore the reserve we had after netdev_alloc_skb_ip_align() */
4031 skb_reserve(skb, NET_SKB_PAD + NET_IP_ALIGN - skb_headroom(skb));
4033 skb->dev = napi->dev;
4039 struct sk_buff *napi_get_frags(struct napi_struct *napi)
4041 struct sk_buff *skb = napi->skb;
4044 skb = netdev_alloc_skb_ip_align(napi->dev, GRO_MAX_HEAD);
4049 EXPORT_SYMBOL(napi_get_frags);
4051 static gro_result_t napi_frags_finish(struct napi_struct *napi, struct sk_buff *skb,
4056 if (netif_receive_skb_internal(skb))
4061 case GRO_MERGED_FREE:
4062 napi_reuse_skb(napi, skb);
4073 static struct sk_buff *napi_frags_skb(struct napi_struct *napi)
4075 struct sk_buff *skb = napi->skb;
4079 if (unlikely(!pskb_may_pull(skb, sizeof(struct ethhdr)))) {
4080 napi_reuse_skb(napi, skb);
4083 skb->protocol = eth_type_trans(skb, skb->dev);
4088 gro_result_t napi_gro_frags(struct napi_struct *napi)
4090 struct sk_buff *skb = napi_frags_skb(napi);
4095 trace_napi_gro_frags_entry(skb);
4097 return napi_frags_finish(napi, skb, dev_gro_receive(napi, skb));
4099 EXPORT_SYMBOL(napi_gro_frags);
4102 * net_rps_action_and_irq_enable sends any pending IPI's for rps.
4103 * Note: called with local irq disabled, but exits with local irq enabled.
4105 static void net_rps_action_and_irq_enable(struct softnet_data *sd)
4108 struct softnet_data *remsd = sd->rps_ipi_list;
4111 sd->rps_ipi_list = NULL;
4115 /* Send pending IPI's to kick RPS processing on remote cpus. */
4117 struct softnet_data *next = remsd->rps_ipi_next;
4119 if (cpu_online(remsd->cpu))
4120 __smp_call_function_single(remsd->cpu,
4129 static int process_backlog(struct napi_struct *napi, int quota)
4132 struct softnet_data *sd = container_of(napi, struct softnet_data, backlog);
4135 /* Check if we have pending ipi, its better to send them now,
4136 * not waiting net_rx_action() end.
4138 if (sd->rps_ipi_list) {
4139 local_irq_disable();
4140 net_rps_action_and_irq_enable(sd);
4143 napi->weight = weight_p;
4144 local_irq_disable();
4145 while (work < quota) {
4146 struct sk_buff *skb;
4149 while ((skb = __skb_dequeue(&sd->process_queue))) {
4151 __netif_receive_skb(skb);
4152 local_irq_disable();
4153 input_queue_head_incr(sd);
4154 if (++work >= quota) {
4161 qlen = skb_queue_len(&sd->input_pkt_queue);
4163 skb_queue_splice_tail_init(&sd->input_pkt_queue,
4164 &sd->process_queue);
4166 if (qlen < quota - work) {
4168 * Inline a custom version of __napi_complete().
4169 * only current cpu owns and manipulates this napi,
4170 * and NAPI_STATE_SCHED is the only possible flag set on backlog.
4171 * we can use a plain write instead of clear_bit(),
4172 * and we dont need an smp_mb() memory barrier.
4174 list_del(&napi->poll_list);
4177 quota = work + qlen;
4187 * __napi_schedule - schedule for receive
4188 * @n: entry to schedule
4190 * The entry's receive function will be scheduled to run
4192 void __napi_schedule(struct napi_struct *n)
4194 unsigned long flags;
4196 local_irq_save(flags);
4197 ____napi_schedule(&__get_cpu_var(softnet_data), n);
4198 local_irq_restore(flags);
4200 EXPORT_SYMBOL(__napi_schedule);
4202 void __napi_complete(struct napi_struct *n)
4204 BUG_ON(!test_bit(NAPI_STATE_SCHED, &n->state));
4205 BUG_ON(n->gro_list);
4207 list_del(&n->poll_list);
4208 smp_mb__before_clear_bit();
4209 clear_bit(NAPI_STATE_SCHED, &n->state);
4211 EXPORT_SYMBOL(__napi_complete);
4213 void napi_complete(struct napi_struct *n)
4215 unsigned long flags;
4218 * don't let napi dequeue from the cpu poll list
4219 * just in case its running on a different cpu
4221 if (unlikely(test_bit(NAPI_STATE_NPSVC, &n->state)))
4224 napi_gro_flush(n, false);
4225 local_irq_save(flags);
4227 local_irq_restore(flags);
4229 EXPORT_SYMBOL(napi_complete);
4231 /* must be called under rcu_read_lock(), as we dont take a reference */
4232 struct napi_struct *napi_by_id(unsigned int napi_id)
4234 unsigned int hash = napi_id % HASH_SIZE(napi_hash);
4235 struct napi_struct *napi;
4237 hlist_for_each_entry_rcu(napi, &napi_hash[hash], napi_hash_node)
4238 if (napi->napi_id == napi_id)
4243 EXPORT_SYMBOL_GPL(napi_by_id);
4245 void napi_hash_add(struct napi_struct *napi)
4247 if (!test_and_set_bit(NAPI_STATE_HASHED, &napi->state)) {
4249 spin_lock(&napi_hash_lock);
4251 /* 0 is not a valid id, we also skip an id that is taken
4252 * we expect both events to be extremely rare
4255 while (!napi->napi_id) {
4256 napi->napi_id = ++napi_gen_id;
4257 if (napi_by_id(napi->napi_id))
4261 hlist_add_head_rcu(&napi->napi_hash_node,
4262 &napi_hash[napi->napi_id % HASH_SIZE(napi_hash)]);
4264 spin_unlock(&napi_hash_lock);
4267 EXPORT_SYMBOL_GPL(napi_hash_add);
4269 /* Warning : caller is responsible to make sure rcu grace period
4270 * is respected before freeing memory containing @napi
4272 void napi_hash_del(struct napi_struct *napi)
4274 spin_lock(&napi_hash_lock);
4276 if (test_and_clear_bit(NAPI_STATE_HASHED, &napi->state))
4277 hlist_del_rcu(&napi->napi_hash_node);
4279 spin_unlock(&napi_hash_lock);
4281 EXPORT_SYMBOL_GPL(napi_hash_del);
4283 void netif_napi_add(struct net_device *dev, struct napi_struct *napi,
4284 int (*poll)(struct napi_struct *, int), int weight)
4286 INIT_LIST_HEAD(&napi->poll_list);
4287 napi->gro_count = 0;
4288 napi->gro_list = NULL;
4291 if (weight > NAPI_POLL_WEIGHT)
4292 pr_err_once("netif_napi_add() called with weight %d on device %s\n",
4294 napi->weight = weight;
4295 list_add(&napi->dev_list, &dev->napi_list);
4297 #ifdef CONFIG_NETPOLL
4298 spin_lock_init(&napi->poll_lock);
4299 napi->poll_owner = -1;
4301 set_bit(NAPI_STATE_SCHED, &napi->state);
4303 EXPORT_SYMBOL(netif_napi_add);
4305 void netif_napi_del(struct napi_struct *napi)
4307 list_del_init(&napi->dev_list);
4308 napi_free_frags(napi);
4310 kfree_skb_list(napi->gro_list);
4311 napi->gro_list = NULL;
4312 napi->gro_count = 0;
4314 EXPORT_SYMBOL(netif_napi_del);
4316 static void net_rx_action(struct softirq_action *h)
4318 struct softnet_data *sd = &__get_cpu_var(softnet_data);
4319 unsigned long time_limit = jiffies + 2;
4320 int budget = netdev_budget;
4323 local_irq_disable();
4325 while (!list_empty(&sd->poll_list)) {
4326 struct napi_struct *n;
4329 /* If softirq window is exhuasted then punt.
4330 * Allow this to run for 2 jiffies since which will allow
4331 * an average latency of 1.5/HZ.
4333 if (unlikely(budget <= 0 || time_after_eq(jiffies, time_limit)))
4338 /* Even though interrupts have been re-enabled, this
4339 * access is safe because interrupts can only add new
4340 * entries to the tail of this list, and only ->poll()
4341 * calls can remove this head entry from the list.
4343 n = list_first_entry(&sd->poll_list, struct napi_struct, poll_list);
4345 have = netpoll_poll_lock(n);
4349 /* This NAPI_STATE_SCHED test is for avoiding a race
4350 * with netpoll's poll_napi(). Only the entity which
4351 * obtains the lock and sees NAPI_STATE_SCHED set will
4352 * actually make the ->poll() call. Therefore we avoid
4353 * accidentally calling ->poll() when NAPI is not scheduled.
4356 if (test_bit(NAPI_STATE_SCHED, &n->state)) {
4357 work = n->poll(n, weight);
4361 WARN_ON_ONCE(work > weight);
4365 local_irq_disable();
4367 /* Drivers must not modify the NAPI state if they
4368 * consume the entire weight. In such cases this code
4369 * still "owns" the NAPI instance and therefore can
4370 * move the instance around on the list at-will.
4372 if (unlikely(work == weight)) {
4373 if (unlikely(napi_disable_pending(n))) {
4376 local_irq_disable();
4379 /* flush too old packets
4380 * If HZ < 1000, flush all packets.
4383 napi_gro_flush(n, HZ >= 1000);
4384 local_irq_disable();
4386 list_move_tail(&n->poll_list, &sd->poll_list);
4390 netpoll_poll_unlock(have);
4393 net_rps_action_and_irq_enable(sd);
4395 #ifdef CONFIG_NET_DMA
4397 * There may not be any more sk_buffs coming right now, so push
4398 * any pending DMA copies to hardware
4400 dma_issue_pending_all();
4407 __raise_softirq_irqoff(NET_RX_SOFTIRQ);
4411 struct netdev_adjacent {
4412 struct net_device *dev;
4414 /* upper master flag, there can only be one master device per list */
4417 /* counter for the number of times this device was added to us */
4420 /* private field for the users */
4423 struct list_head list;
4424 struct rcu_head rcu;
4427 static struct netdev_adjacent *__netdev_find_adj(struct net_device *dev,
4428 struct net_device *adj_dev,
4429 struct list_head *adj_list)
4431 struct netdev_adjacent *adj;
4433 list_for_each_entry(adj, adj_list, list) {
4434 if (adj->dev == adj_dev)
4441 * netdev_has_upper_dev - Check if device is linked to an upper device
4443 * @upper_dev: upper device to check
4445 * Find out if a device is linked to specified upper device and return true
4446 * in case it is. Note that this checks only immediate upper device,
4447 * not through a complete stack of devices. The caller must hold the RTNL lock.
4449 bool netdev_has_upper_dev(struct net_device *dev,
4450 struct net_device *upper_dev)
4454 return __netdev_find_adj(dev, upper_dev, &dev->all_adj_list.upper);
4456 EXPORT_SYMBOL(netdev_has_upper_dev);
4459 * netdev_has_any_upper_dev - Check if device is linked to some device
4462 * Find out if a device is linked to an upper device and return true in case
4463 * it is. The caller must hold the RTNL lock.
4465 static bool netdev_has_any_upper_dev(struct net_device *dev)
4469 return !list_empty(&dev->all_adj_list.upper);
4473 * netdev_master_upper_dev_get - Get master upper device
4476 * Find a master upper device and return pointer to it or NULL in case
4477 * it's not there. The caller must hold the RTNL lock.
4479 struct net_device *netdev_master_upper_dev_get(struct net_device *dev)
4481 struct netdev_adjacent *upper;
4485 if (list_empty(&dev->adj_list.upper))
4488 upper = list_first_entry(&dev->adj_list.upper,
4489 struct netdev_adjacent, list);
4490 if (likely(upper->master))
4494 EXPORT_SYMBOL(netdev_master_upper_dev_get);
4496 void *netdev_adjacent_get_private(struct list_head *adj_list)
4498 struct netdev_adjacent *adj;
4500 adj = list_entry(adj_list, struct netdev_adjacent, list);
4502 return adj->private;
4504 EXPORT_SYMBOL(netdev_adjacent_get_private);
4507 * netdev_all_upper_get_next_dev_rcu - Get the next dev from upper list
4509 * @iter: list_head ** of the current position
4511 * Gets the next device from the dev's upper list, starting from iter
4512 * position. The caller must hold RCU read lock.
4514 struct net_device *netdev_all_upper_get_next_dev_rcu(struct net_device *dev,
4515 struct list_head **iter)
4517 struct netdev_adjacent *upper;
4519 WARN_ON_ONCE(!rcu_read_lock_held() && !lockdep_rtnl_is_held());
4521 upper = list_entry_rcu((*iter)->next, struct netdev_adjacent, list);
4523 if (&upper->list == &dev->all_adj_list.upper)
4526 *iter = &upper->list;
4530 EXPORT_SYMBOL(netdev_all_upper_get_next_dev_rcu);
4533 * netdev_lower_get_next_private - Get the next ->private from the
4534 * lower neighbour list
4536 * @iter: list_head ** of the current position
4538 * Gets the next netdev_adjacent->private from the dev's lower neighbour
4539 * list, starting from iter position. The caller must hold either hold the
4540 * RTNL lock or its own locking that guarantees that the neighbour lower
4541 * list will remain unchainged.
4543 void *netdev_lower_get_next_private(struct net_device *dev,
4544 struct list_head **iter)
4546 struct netdev_adjacent *lower;
4548 lower = list_entry(*iter, struct netdev_adjacent, list);
4550 if (&lower->list == &dev->adj_list.lower)
4554 *iter = lower->list.next;
4556 return lower->private;
4558 EXPORT_SYMBOL(netdev_lower_get_next_private);
4561 * netdev_lower_get_next_private_rcu - Get the next ->private from the
4562 * lower neighbour list, RCU
4565 * @iter: list_head ** of the current position
4567 * Gets the next netdev_adjacent->private from the dev's lower neighbour
4568 * list, starting from iter position. The caller must hold RCU read lock.
4570 void *netdev_lower_get_next_private_rcu(struct net_device *dev,
4571 struct list_head **iter)
4573 struct netdev_adjacent *lower;
4575 WARN_ON_ONCE(!rcu_read_lock_held());
4577 lower = list_entry_rcu((*iter)->next, struct netdev_adjacent, list);
4579 if (&lower->list == &dev->adj_list.lower)
4583 *iter = &lower->list;
4585 return lower->private;
4587 EXPORT_SYMBOL(netdev_lower_get_next_private_rcu);
4590 * netdev_lower_get_first_private_rcu - Get the first ->private from the
4591 * lower neighbour list, RCU
4595 * Gets the first netdev_adjacent->private from the dev's lower neighbour
4596 * list. The caller must hold RCU read lock.
4598 void *netdev_lower_get_first_private_rcu(struct net_device *dev)
4600 struct netdev_adjacent *lower;
4602 lower = list_first_or_null_rcu(&dev->adj_list.lower,
4603 struct netdev_adjacent, list);
4605 return lower->private;
4608 EXPORT_SYMBOL(netdev_lower_get_first_private_rcu);
4611 * netdev_master_upper_dev_get_rcu - Get master upper device
4614 * Find a master upper device and return pointer to it or NULL in case
4615 * it's not there. The caller must hold the RCU read lock.
4617 struct net_device *netdev_master_upper_dev_get_rcu(struct net_device *dev)
4619 struct netdev_adjacent *upper;
4621 upper = list_first_or_null_rcu(&dev->adj_list.upper,
4622 struct netdev_adjacent, list);
4623 if (upper && likely(upper->master))
4627 EXPORT_SYMBOL(netdev_master_upper_dev_get_rcu);
4629 int netdev_adjacent_sysfs_add(struct net_device *dev,
4630 struct net_device *adj_dev,
4631 struct list_head *dev_list)
4633 char linkname[IFNAMSIZ+7];
4634 sprintf(linkname, dev_list == &dev->adj_list.upper ?
4635 "upper_%s" : "lower_%s", adj_dev->name);
4636 return sysfs_create_link(&(dev->dev.kobj), &(adj_dev->dev.kobj),
4639 void netdev_adjacent_sysfs_del(struct net_device *dev,
4641 struct list_head *dev_list)
4643 char linkname[IFNAMSIZ+7];
4644 sprintf(linkname, dev_list == &dev->adj_list.upper ?
4645 "upper_%s" : "lower_%s", name);
4646 sysfs_remove_link(&(dev->dev.kobj), linkname);
4649 #define netdev_adjacent_is_neigh_list(dev, dev_list) \
4650 (dev_list == &dev->adj_list.upper || \
4651 dev_list == &dev->adj_list.lower)
4653 static int __netdev_adjacent_dev_insert(struct net_device *dev,
4654 struct net_device *adj_dev,
4655 struct list_head *dev_list,
4656 void *private, bool master)
4658 struct netdev_adjacent *adj;
4661 adj = __netdev_find_adj(dev, adj_dev, dev_list);
4668 adj = kmalloc(sizeof(*adj), GFP_KERNEL);
4673 adj->master = master;
4675 adj->private = private;
4678 pr_debug("dev_hold for %s, because of link added from %s to %s\n",
4679 adj_dev->name, dev->name, adj_dev->name);
4681 if (netdev_adjacent_is_neigh_list(dev, dev_list)) {
4682 ret = netdev_adjacent_sysfs_add(dev, adj_dev, dev_list);
4687 /* Ensure that master link is always the first item in list. */
4689 ret = sysfs_create_link(&(dev->dev.kobj),
4690 &(adj_dev->dev.kobj), "master");
4692 goto remove_symlinks;
4694 list_add_rcu(&adj->list, dev_list);
4696 list_add_tail_rcu(&adj->list, dev_list);
4702 if (netdev_adjacent_is_neigh_list(dev, dev_list))
4703 netdev_adjacent_sysfs_del(dev, adj_dev->name, dev_list);
4711 static void __netdev_adjacent_dev_remove(struct net_device *dev,
4712 struct net_device *adj_dev,
4713 struct list_head *dev_list)
4715 struct netdev_adjacent *adj;
4717 adj = __netdev_find_adj(dev, adj_dev, dev_list);
4720 pr_err("tried to remove device %s from %s\n",
4721 dev->name, adj_dev->name);
4725 if (adj->ref_nr > 1) {
4726 pr_debug("%s to %s ref_nr-- = %d\n", dev->name, adj_dev->name,
4733 sysfs_remove_link(&(dev->dev.kobj), "master");
4735 if (netdev_adjacent_is_neigh_list(dev, dev_list))
4736 netdev_adjacent_sysfs_del(dev, adj_dev->name, dev_list);
4738 list_del_rcu(&adj->list);
4739 pr_debug("dev_put for %s, because link removed from %s to %s\n",
4740 adj_dev->name, dev->name, adj_dev->name);
4742 kfree_rcu(adj, rcu);
4745 static int __netdev_adjacent_dev_link_lists(struct net_device *dev,
4746 struct net_device *upper_dev,
4747 struct list_head *up_list,
4748 struct list_head *down_list,
4749 void *private, bool master)
4753 ret = __netdev_adjacent_dev_insert(dev, upper_dev, up_list, private,
4758 ret = __netdev_adjacent_dev_insert(upper_dev, dev, down_list, private,
4761 __netdev_adjacent_dev_remove(dev, upper_dev, up_list);
4768 static int __netdev_adjacent_dev_link(struct net_device *dev,
4769 struct net_device *upper_dev)
4771 return __netdev_adjacent_dev_link_lists(dev, upper_dev,
4772 &dev->all_adj_list.upper,
4773 &upper_dev->all_adj_list.lower,
4777 static void __netdev_adjacent_dev_unlink_lists(struct net_device *dev,
4778 struct net_device *upper_dev,
4779 struct list_head *up_list,
4780 struct list_head *down_list)
4782 __netdev_adjacent_dev_remove(dev, upper_dev, up_list);
4783 __netdev_adjacent_dev_remove(upper_dev, dev, down_list);
4786 static void __netdev_adjacent_dev_unlink(struct net_device *dev,
4787 struct net_device *upper_dev)
4789 __netdev_adjacent_dev_unlink_lists(dev, upper_dev,
4790 &dev->all_adj_list.upper,
4791 &upper_dev->all_adj_list.lower);
4794 static int __netdev_adjacent_dev_link_neighbour(struct net_device *dev,
4795 struct net_device *upper_dev,
4796 void *private, bool master)
4798 int ret = __netdev_adjacent_dev_link(dev, upper_dev);
4803 ret = __netdev_adjacent_dev_link_lists(dev, upper_dev,
4804 &dev->adj_list.upper,
4805 &upper_dev->adj_list.lower,
4808 __netdev_adjacent_dev_unlink(dev, upper_dev);
4815 static void __netdev_adjacent_dev_unlink_neighbour(struct net_device *dev,
4816 struct net_device *upper_dev)
4818 __netdev_adjacent_dev_unlink(dev, upper_dev);
4819 __netdev_adjacent_dev_unlink_lists(dev, upper_dev,
4820 &dev->adj_list.upper,
4821 &upper_dev->adj_list.lower);
4824 static int __netdev_upper_dev_link(struct net_device *dev,
4825 struct net_device *upper_dev, bool master,
4828 struct netdev_adjacent *i, *j, *to_i, *to_j;
4833 if (dev == upper_dev)
4836 /* To prevent loops, check if dev is not upper device to upper_dev. */
4837 if (__netdev_find_adj(upper_dev, dev, &upper_dev->all_adj_list.upper))
4840 if (__netdev_find_adj(dev, upper_dev, &dev->all_adj_list.upper))
4843 if (master && netdev_master_upper_dev_get(dev))
4846 ret = __netdev_adjacent_dev_link_neighbour(dev, upper_dev, private,
4851 /* Now that we linked these devs, make all the upper_dev's
4852 * all_adj_list.upper visible to every dev's all_adj_list.lower an
4853 * versa, and don't forget the devices itself. All of these
4854 * links are non-neighbours.
4856 list_for_each_entry(i, &dev->all_adj_list.lower, list) {
4857 list_for_each_entry(j, &upper_dev->all_adj_list.upper, list) {
4858 pr_debug("Interlinking %s with %s, non-neighbour\n",
4859 i->dev->name, j->dev->name);
4860 ret = __netdev_adjacent_dev_link(i->dev, j->dev);
4866 /* add dev to every upper_dev's upper device */
4867 list_for_each_entry(i, &upper_dev->all_adj_list.upper, list) {
4868 pr_debug("linking %s's upper device %s with %s\n",
4869 upper_dev->name, i->dev->name, dev->name);
4870 ret = __netdev_adjacent_dev_link(dev, i->dev);
4872 goto rollback_upper_mesh;
4875 /* add upper_dev to every dev's lower device */
4876 list_for_each_entry(i, &dev->all_adj_list.lower, list) {
4877 pr_debug("linking %s's lower device %s with %s\n", dev->name,
4878 i->dev->name, upper_dev->name);
4879 ret = __netdev_adjacent_dev_link(i->dev, upper_dev);
4881 goto rollback_lower_mesh;
4884 call_netdevice_notifiers(NETDEV_CHANGEUPPER, dev);
4887 rollback_lower_mesh:
4889 list_for_each_entry(i, &dev->all_adj_list.lower, list) {
4892 __netdev_adjacent_dev_unlink(i->dev, upper_dev);
4897 rollback_upper_mesh:
4899 list_for_each_entry(i, &upper_dev->all_adj_list.upper, list) {
4902 __netdev_adjacent_dev_unlink(dev, i->dev);
4910 list_for_each_entry(i, &dev->all_adj_list.lower, list) {
4911 list_for_each_entry(j, &upper_dev->all_adj_list.upper, list) {
4912 if (i == to_i && j == to_j)
4914 __netdev_adjacent_dev_unlink(i->dev, j->dev);
4920 __netdev_adjacent_dev_unlink_neighbour(dev, upper_dev);
4926 * netdev_upper_dev_link - Add a link to the upper device
4928 * @upper_dev: new upper device
4930 * Adds a link to device which is upper to this one. The caller must hold
4931 * the RTNL lock. On a failure a negative errno code is returned.
4932 * On success the reference counts are adjusted and the function
4935 int netdev_upper_dev_link(struct net_device *dev,
4936 struct net_device *upper_dev)
4938 return __netdev_upper_dev_link(dev, upper_dev, false, NULL);
4940 EXPORT_SYMBOL(netdev_upper_dev_link);
4943 * netdev_master_upper_dev_link - Add a master link to the upper device
4945 * @upper_dev: new upper device
4947 * Adds a link to device which is upper to this one. In this case, only
4948 * one master upper device can be linked, although other non-master devices
4949 * might be linked as well. The caller must hold the RTNL lock.
4950 * On a failure a negative errno code is returned. On success the reference
4951 * counts are adjusted and the function returns zero.
4953 int netdev_master_upper_dev_link(struct net_device *dev,
4954 struct net_device *upper_dev)
4956 return __netdev_upper_dev_link(dev, upper_dev, true, NULL);
4958 EXPORT_SYMBOL(netdev_master_upper_dev_link);
4960 int netdev_master_upper_dev_link_private(struct net_device *dev,
4961 struct net_device *upper_dev,
4964 return __netdev_upper_dev_link(dev, upper_dev, true, private);
4966 EXPORT_SYMBOL(netdev_master_upper_dev_link_private);
4969 * netdev_upper_dev_unlink - Removes a link to upper device
4971 * @upper_dev: new upper device
4973 * Removes a link to device which is upper to this one. The caller must hold
4976 void netdev_upper_dev_unlink(struct net_device *dev,
4977 struct net_device *upper_dev)
4979 struct netdev_adjacent *i, *j;
4982 __netdev_adjacent_dev_unlink_neighbour(dev, upper_dev);
4984 /* Here is the tricky part. We must remove all dev's lower
4985 * devices from all upper_dev's upper devices and vice
4986 * versa, to maintain the graph relationship.
4988 list_for_each_entry(i, &dev->all_adj_list.lower, list)
4989 list_for_each_entry(j, &upper_dev->all_adj_list.upper, list)
4990 __netdev_adjacent_dev_unlink(i->dev, j->dev);
4992 /* remove also the devices itself from lower/upper device
4995 list_for_each_entry(i, &dev->all_adj_list.lower, list)
4996 __netdev_adjacent_dev_unlink(i->dev, upper_dev);
4998 list_for_each_entry(i, &upper_dev->all_adj_list.upper, list)
4999 __netdev_adjacent_dev_unlink(dev, i->dev);
5001 call_netdevice_notifiers(NETDEV_CHANGEUPPER, dev);
5003 EXPORT_SYMBOL(netdev_upper_dev_unlink);
5005 void netdev_adjacent_rename_links(struct net_device *dev, char *oldname)
5007 struct netdev_adjacent *iter;
5009 list_for_each_entry(iter, &dev->adj_list.upper, list) {
5010 netdev_adjacent_sysfs_del(iter->dev, oldname,
5011 &iter->dev->adj_list.lower);
5012 netdev_adjacent_sysfs_add(iter->dev, dev,
5013 &iter->dev->adj_list.lower);
5016 list_for_each_entry(iter, &dev->adj_list.lower, list) {
5017 netdev_adjacent_sysfs_del(iter->dev, oldname,
5018 &iter->dev->adj_list.upper);
5019 netdev_adjacent_sysfs_add(iter->dev, dev,
5020 &iter->dev->adj_list.upper);
5024 void *netdev_lower_dev_get_private(struct net_device *dev,
5025 struct net_device *lower_dev)
5027 struct netdev_adjacent *lower;
5031 lower = __netdev_find_adj(dev, lower_dev, &dev->adj_list.lower);
5035 return lower->private;
5037 EXPORT_SYMBOL(netdev_lower_dev_get_private);
5039 static void dev_change_rx_flags(struct net_device *dev, int flags)
5041 const struct net_device_ops *ops = dev->netdev_ops;
5043 if (ops->ndo_change_rx_flags)
5044 ops->ndo_change_rx_flags(dev, flags);
5047 static int __dev_set_promiscuity(struct net_device *dev, int inc, bool notify)
5049 unsigned int old_flags = dev->flags;
5055 dev->flags |= IFF_PROMISC;
5056 dev->promiscuity += inc;
5057 if (dev->promiscuity == 0) {
5060 * If inc causes overflow, untouch promisc and return error.
5063 dev->flags &= ~IFF_PROMISC;
5065 dev->promiscuity -= inc;
5066 pr_warn("%s: promiscuity touches roof, set promiscuity failed. promiscuity feature of device might be broken.\n",
5071 if (dev->flags != old_flags) {
5072 pr_info("device %s %s promiscuous mode\n",
5074 dev->flags & IFF_PROMISC ? "entered" : "left");
5075 if (audit_enabled) {
5076 current_uid_gid(&uid, &gid);
5077 audit_log(current->audit_context, GFP_ATOMIC,
5078 AUDIT_ANOM_PROMISCUOUS,
5079 "dev=%s prom=%d old_prom=%d auid=%u uid=%u gid=%u ses=%u",
5080 dev->name, (dev->flags & IFF_PROMISC),
5081 (old_flags & IFF_PROMISC),
5082 from_kuid(&init_user_ns, audit_get_loginuid(current)),
5083 from_kuid(&init_user_ns, uid),
5084 from_kgid(&init_user_ns, gid),
5085 audit_get_sessionid(current));
5088 dev_change_rx_flags(dev, IFF_PROMISC);
5091 __dev_notify_flags(dev, old_flags, IFF_PROMISC);
5096 * dev_set_promiscuity - update promiscuity count on a device
5100 * Add or remove promiscuity from a device. While the count in the device
5101 * remains above zero the interface remains promiscuous. Once it hits zero
5102 * the device reverts back to normal filtering operation. A negative inc
5103 * value is used to drop promiscuity on the device.
5104 * Return 0 if successful or a negative errno code on error.
5106 int dev_set_promiscuity(struct net_device *dev, int inc)
5108 unsigned int old_flags = dev->flags;
5111 err = __dev_set_promiscuity(dev, inc, true);
5114 if (dev->flags != old_flags)
5115 dev_set_rx_mode(dev);
5118 EXPORT_SYMBOL(dev_set_promiscuity);
5120 static int __dev_set_allmulti(struct net_device *dev, int inc, bool notify)
5122 unsigned int old_flags = dev->flags, old_gflags = dev->gflags;
5126 dev->flags |= IFF_ALLMULTI;
5127 dev->allmulti += inc;
5128 if (dev->allmulti == 0) {
5131 * If inc causes overflow, untouch allmulti and return error.
5134 dev->flags &= ~IFF_ALLMULTI;
5136 dev->allmulti -= inc;
5137 pr_warn("%s: allmulti touches roof, set allmulti failed. allmulti feature of device might be broken.\n",
5142 if (dev->flags ^ old_flags) {
5143 dev_change_rx_flags(dev, IFF_ALLMULTI);
5144 dev_set_rx_mode(dev);
5146 __dev_notify_flags(dev, old_flags,
5147 dev->gflags ^ old_gflags);
5153 * dev_set_allmulti - update allmulti count on a device
5157 * Add or remove reception of all multicast frames to a device. While the
5158 * count in the device remains above zero the interface remains listening
5159 * to all interfaces. Once it hits zero the device reverts back to normal
5160 * filtering operation. A negative @inc value is used to drop the counter
5161 * when releasing a resource needing all multicasts.
5162 * Return 0 if successful or a negative errno code on error.
5165 int dev_set_allmulti(struct net_device *dev, int inc)
5167 return __dev_set_allmulti(dev, inc, true);
5169 EXPORT_SYMBOL(dev_set_allmulti);
5172 * Upload unicast and multicast address lists to device and
5173 * configure RX filtering. When the device doesn't support unicast
5174 * filtering it is put in promiscuous mode while unicast addresses
5177 void __dev_set_rx_mode(struct net_device *dev)
5179 const struct net_device_ops *ops = dev->netdev_ops;
5181 /* dev_open will call this function so the list will stay sane. */
5182 if (!(dev->flags&IFF_UP))
5185 if (!netif_device_present(dev))
5188 if (!(dev->priv_flags & IFF_UNICAST_FLT)) {
5189 /* Unicast addresses changes may only happen under the rtnl,
5190 * therefore calling __dev_set_promiscuity here is safe.
5192 if (!netdev_uc_empty(dev) && !dev->uc_promisc) {
5193 __dev_set_promiscuity(dev, 1, false);
5194 dev->uc_promisc = true;
5195 } else if (netdev_uc_empty(dev) && dev->uc_promisc) {
5196 __dev_set_promiscuity(dev, -1, false);
5197 dev->uc_promisc = false;
5201 if (ops->ndo_set_rx_mode)
5202 ops->ndo_set_rx_mode(dev);
5205 void dev_set_rx_mode(struct net_device *dev)
5207 netif_addr_lock_bh(dev);
5208 __dev_set_rx_mode(dev);
5209 netif_addr_unlock_bh(dev);
5213 * dev_get_flags - get flags reported to userspace
5216 * Get the combination of flag bits exported through APIs to userspace.
5218 unsigned int dev_get_flags(const struct net_device *dev)
5222 flags = (dev->flags & ~(IFF_PROMISC |
5227 (dev->gflags & (IFF_PROMISC |
5230 if (netif_running(dev)) {
5231 if (netif_oper_up(dev))
5232 flags |= IFF_RUNNING;
5233 if (netif_carrier_ok(dev))
5234 flags |= IFF_LOWER_UP;
5235 if (netif_dormant(dev))
5236 flags |= IFF_DORMANT;
5241 EXPORT_SYMBOL(dev_get_flags);
5243 int __dev_change_flags(struct net_device *dev, unsigned int flags)
5245 unsigned int old_flags = dev->flags;
5251 * Set the flags on our device.
5254 dev->flags = (flags & (IFF_DEBUG | IFF_NOTRAILERS | IFF_NOARP |
5255 IFF_DYNAMIC | IFF_MULTICAST | IFF_PORTSEL |
5257 (dev->flags & (IFF_UP | IFF_VOLATILE | IFF_PROMISC |
5261 * Load in the correct multicast list now the flags have changed.
5264 if ((old_flags ^ flags) & IFF_MULTICAST)
5265 dev_change_rx_flags(dev, IFF_MULTICAST);
5267 dev_set_rx_mode(dev);
5270 * Have we downed the interface. We handle IFF_UP ourselves
5271 * according to user attempts to set it, rather than blindly
5276 if ((old_flags ^ flags) & IFF_UP) { /* Bit is different ? */
5277 ret = ((old_flags & IFF_UP) ? __dev_close : __dev_open)(dev);
5280 dev_set_rx_mode(dev);
5283 if ((flags ^ dev->gflags) & IFF_PROMISC) {
5284 int inc = (flags & IFF_PROMISC) ? 1 : -1;
5285 unsigned int old_flags = dev->flags;
5287 dev->gflags ^= IFF_PROMISC;
5289 if (__dev_set_promiscuity(dev, inc, false) >= 0)
5290 if (dev->flags != old_flags)
5291 dev_set_rx_mode(dev);
5294 /* NOTE: order of synchronization of IFF_PROMISC and IFF_ALLMULTI
5295 is important. Some (broken) drivers set IFF_PROMISC, when
5296 IFF_ALLMULTI is requested not asking us and not reporting.
5298 if ((flags ^ dev->gflags) & IFF_ALLMULTI) {
5299 int inc = (flags & IFF_ALLMULTI) ? 1 : -1;
5301 dev->gflags ^= IFF_ALLMULTI;
5302 __dev_set_allmulti(dev, inc, false);
5308 void __dev_notify_flags(struct net_device *dev, unsigned int old_flags,
5309 unsigned int gchanges)
5311 unsigned int changes = dev->flags ^ old_flags;
5314 rtmsg_ifinfo(RTM_NEWLINK, dev, gchanges, GFP_ATOMIC);
5316 if (changes & IFF_UP) {
5317 if (dev->flags & IFF_UP)
5318 call_netdevice_notifiers(NETDEV_UP, dev);
5320 call_netdevice_notifiers(NETDEV_DOWN, dev);
5323 if (dev->flags & IFF_UP &&
5324 (changes & ~(IFF_UP | IFF_PROMISC | IFF_ALLMULTI | IFF_VOLATILE))) {
5325 struct netdev_notifier_change_info change_info;
5327 change_info.flags_changed = changes;
5328 call_netdevice_notifiers_info(NETDEV_CHANGE, dev,
5334 * dev_change_flags - change device settings
5336 * @flags: device state flags
5338 * Change settings on device based state flags. The flags are
5339 * in the userspace exported format.
5341 int dev_change_flags(struct net_device *dev, unsigned int flags)
5344 unsigned int changes, old_flags = dev->flags, old_gflags = dev->gflags;
5346 ret = __dev_change_flags(dev, flags);
5350 changes = (old_flags ^ dev->flags) | (old_gflags ^ dev->gflags);
5351 __dev_notify_flags(dev, old_flags, changes);
5354 EXPORT_SYMBOL(dev_change_flags);
5356 static int __dev_set_mtu(struct net_device *dev, int new_mtu)
5358 const struct net_device_ops *ops = dev->netdev_ops;
5360 if (ops->ndo_change_mtu)
5361 return ops->ndo_change_mtu(dev, new_mtu);
5368 * dev_set_mtu - Change maximum transfer unit
5370 * @new_mtu: new transfer unit
5372 * Change the maximum transfer size of the network device.
5374 int dev_set_mtu(struct net_device *dev, int new_mtu)
5378 if (new_mtu == dev->mtu)
5381 /* MTU must be positive. */
5385 if (!netif_device_present(dev))
5388 orig_mtu = dev->mtu;
5389 err = __dev_set_mtu(dev, new_mtu);
5392 err = call_netdevice_notifiers(NETDEV_CHANGEMTU, dev);
5393 err = notifier_to_errno(err);
5395 /* setting mtu back and notifying everyone again,
5396 * so that they have a chance to revert changes.
5398 __dev_set_mtu(dev, orig_mtu);
5399 call_netdevice_notifiers(NETDEV_CHANGEMTU, dev);
5404 EXPORT_SYMBOL(dev_set_mtu);
5407 * dev_set_group - Change group this device belongs to
5409 * @new_group: group this device should belong to
5411 void dev_set_group(struct net_device *dev, int new_group)
5413 dev->group = new_group;
5415 EXPORT_SYMBOL(dev_set_group);
5418 * dev_set_mac_address - Change Media Access Control Address
5422 * Change the hardware (MAC) address of the device
5424 int dev_set_mac_address(struct net_device *dev, struct sockaddr *sa)
5426 const struct net_device_ops *ops = dev->netdev_ops;
5429 if (!ops->ndo_set_mac_address)
5431 if (sa->sa_family != dev->type)
5433 if (!netif_device_present(dev))
5435 err = ops->ndo_set_mac_address(dev, sa);
5438 dev->addr_assign_type = NET_ADDR_SET;
5439 call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
5440 add_device_randomness(dev->dev_addr, dev->addr_len);
5443 EXPORT_SYMBOL(dev_set_mac_address);
5446 * dev_change_carrier - Change device carrier
5448 * @new_carrier: new value
5450 * Change device carrier
5452 int dev_change_carrier(struct net_device *dev, bool new_carrier)
5454 const struct net_device_ops *ops = dev->netdev_ops;
5456 if (!ops->ndo_change_carrier)
5458 if (!netif_device_present(dev))
5460 return ops->ndo_change_carrier(dev, new_carrier);
5462 EXPORT_SYMBOL(dev_change_carrier);
5465 * dev_get_phys_port_id - Get device physical port ID
5469 * Get device physical port ID
5471 int dev_get_phys_port_id(struct net_device *dev,
5472 struct netdev_phys_port_id *ppid)
5474 const struct net_device_ops *ops = dev->netdev_ops;
5476 if (!ops->ndo_get_phys_port_id)
5478 return ops->ndo_get_phys_port_id(dev, ppid);
5480 EXPORT_SYMBOL(dev_get_phys_port_id);
5483 * dev_new_index - allocate an ifindex
5484 * @net: the applicable net namespace
5486 * Returns a suitable unique value for a new device interface
5487 * number. The caller must hold the rtnl semaphore or the
5488 * dev_base_lock to be sure it remains unique.
5490 static int dev_new_index(struct net *net)
5492 int ifindex = net->ifindex;
5496 if (!__dev_get_by_index(net, ifindex))
5497 return net->ifindex = ifindex;
5501 /* Delayed registration/unregisteration */
5502 static LIST_HEAD(net_todo_list);
5503 static DECLARE_WAIT_QUEUE_HEAD(netdev_unregistering_wq);
5505 static void net_set_todo(struct net_device *dev)
5507 list_add_tail(&dev->todo_list, &net_todo_list);
5508 dev_net(dev)->dev_unreg_count++;
5511 static void rollback_registered_many(struct list_head *head)
5513 struct net_device *dev, *tmp;
5514 LIST_HEAD(close_head);
5516 BUG_ON(dev_boot_phase);
5519 list_for_each_entry_safe(dev, tmp, head, unreg_list) {
5520 /* Some devices call without registering
5521 * for initialization unwind. Remove those
5522 * devices and proceed with the remaining.
5524 if (dev->reg_state == NETREG_UNINITIALIZED) {
5525 pr_debug("unregister_netdevice: device %s/%p never was registered\n",
5529 list_del(&dev->unreg_list);
5532 dev->dismantle = true;
5533 BUG_ON(dev->reg_state != NETREG_REGISTERED);
5536 /* If device is running, close it first. */
5537 list_for_each_entry(dev, head, unreg_list)
5538 list_add_tail(&dev->close_list, &close_head);
5539 dev_close_many(&close_head);
5541 list_for_each_entry(dev, head, unreg_list) {
5542 /* And unlink it from device chain. */
5543 unlist_netdevice(dev);
5545 dev->reg_state = NETREG_UNREGISTERING;
5550 list_for_each_entry(dev, head, unreg_list) {
5551 /* Shutdown queueing discipline. */
5555 /* Notify protocols, that we are about to destroy
5556 this device. They should clean all the things.
5558 call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
5560 if (!dev->rtnl_link_ops ||
5561 dev->rtnl_link_state == RTNL_LINK_INITIALIZED)
5562 rtmsg_ifinfo(RTM_DELLINK, dev, ~0U, GFP_KERNEL);
5565 * Flush the unicast and multicast chains
5570 if (dev->netdev_ops->ndo_uninit)
5571 dev->netdev_ops->ndo_uninit(dev);
5573 /* Notifier chain MUST detach us all upper devices. */
5574 WARN_ON(netdev_has_any_upper_dev(dev));
5576 /* Remove entries from kobject tree */
5577 netdev_unregister_kobject(dev);
5579 /* Remove XPS queueing entries */
5580 netif_reset_xps_queues_gt(dev, 0);
5586 list_for_each_entry(dev, head, unreg_list)
5590 static void rollback_registered(struct net_device *dev)
5594 list_add(&dev->unreg_list, &single);
5595 rollback_registered_many(&single);
5599 static netdev_features_t netdev_fix_features(struct net_device *dev,
5600 netdev_features_t features)
5602 /* Fix illegal checksum combinations */
5603 if ((features & NETIF_F_HW_CSUM) &&
5604 (features & (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))) {
5605 netdev_warn(dev, "mixed HW and IP checksum settings.\n");
5606 features &= ~(NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM);
5609 /* TSO requires that SG is present as well. */
5610 if ((features & NETIF_F_ALL_TSO) && !(features & NETIF_F_SG)) {
5611 netdev_dbg(dev, "Dropping TSO features since no SG feature.\n");
5612 features &= ~NETIF_F_ALL_TSO;
5615 if ((features & NETIF_F_TSO) && !(features & NETIF_F_HW_CSUM) &&
5616 !(features & NETIF_F_IP_CSUM)) {
5617 netdev_dbg(dev, "Dropping TSO features since no CSUM feature.\n");
5618 features &= ~NETIF_F_TSO;
5619 features &= ~NETIF_F_TSO_ECN;
5622 if ((features & NETIF_F_TSO6) && !(features & NETIF_F_HW_CSUM) &&
5623 !(features & NETIF_F_IPV6_CSUM)) {
5624 netdev_dbg(dev, "Dropping TSO6 features since no CSUM feature.\n");
5625 features &= ~NETIF_F_TSO6;
5628 /* TSO ECN requires that TSO is present as well. */
5629 if ((features & NETIF_F_ALL_TSO) == NETIF_F_TSO_ECN)
5630 features &= ~NETIF_F_TSO_ECN;
5632 /* Software GSO depends on SG. */
5633 if ((features & NETIF_F_GSO) && !(features & NETIF_F_SG)) {
5634 netdev_dbg(dev, "Dropping NETIF_F_GSO since no SG feature.\n");
5635 features &= ~NETIF_F_GSO;
5638 /* UFO needs SG and checksumming */
5639 if (features & NETIF_F_UFO) {
5640 /* maybe split UFO into V4 and V6? */
5641 if (!((features & NETIF_F_GEN_CSUM) ||
5642 (features & (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))
5643 == (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))) {
5645 "Dropping NETIF_F_UFO since no checksum offload features.\n");
5646 features &= ~NETIF_F_UFO;
5649 if (!(features & NETIF_F_SG)) {
5651 "Dropping NETIF_F_UFO since no NETIF_F_SG feature.\n");
5652 features &= ~NETIF_F_UFO;
5659 int __netdev_update_features(struct net_device *dev)
5661 netdev_features_t features;
5666 features = netdev_get_wanted_features(dev);
5668 if (dev->netdev_ops->ndo_fix_features)
5669 features = dev->netdev_ops->ndo_fix_features(dev, features);
5671 /* driver might be less strict about feature dependencies */
5672 features = netdev_fix_features(dev, features);
5674 if (dev->features == features)
5677 netdev_dbg(dev, "Features changed: %pNF -> %pNF\n",
5678 &dev->features, &features);
5680 if (dev->netdev_ops->ndo_set_features)
5681 err = dev->netdev_ops->ndo_set_features(dev, features);
5683 if (unlikely(err < 0)) {
5685 "set_features() failed (%d); wanted %pNF, left %pNF\n",
5686 err, &features, &dev->features);
5691 dev->features = features;
5697 * netdev_update_features - recalculate device features
5698 * @dev: the device to check
5700 * Recalculate dev->features set and send notifications if it
5701 * has changed. Should be called after driver or hardware dependent
5702 * conditions might have changed that influence the features.
5704 void netdev_update_features(struct net_device *dev)
5706 if (__netdev_update_features(dev))
5707 netdev_features_change(dev);
5709 EXPORT_SYMBOL(netdev_update_features);
5712 * netdev_change_features - recalculate device features
5713 * @dev: the device to check
5715 * Recalculate dev->features set and send notifications even
5716 * if they have not changed. Should be called instead of
5717 * netdev_update_features() if also dev->vlan_features might
5718 * have changed to allow the changes to be propagated to stacked
5721 void netdev_change_features(struct net_device *dev)
5723 __netdev_update_features(dev);
5724 netdev_features_change(dev);
5726 EXPORT_SYMBOL(netdev_change_features);
5729 * netif_stacked_transfer_operstate - transfer operstate
5730 * @rootdev: the root or lower level device to transfer state from
5731 * @dev: the device to transfer operstate to
5733 * Transfer operational state from root to device. This is normally
5734 * called when a stacking relationship exists between the root
5735 * device and the device(a leaf device).
5737 void netif_stacked_transfer_operstate(const struct net_device *rootdev,
5738 struct net_device *dev)
5740 if (rootdev->operstate == IF_OPER_DORMANT)
5741 netif_dormant_on(dev);
5743 netif_dormant_off(dev);
5745 if (netif_carrier_ok(rootdev)) {
5746 if (!netif_carrier_ok(dev))
5747 netif_carrier_on(dev);
5749 if (netif_carrier_ok(dev))
5750 netif_carrier_off(dev);
5753 EXPORT_SYMBOL(netif_stacked_transfer_operstate);
5756 static int netif_alloc_rx_queues(struct net_device *dev)
5758 unsigned int i, count = dev->num_rx_queues;
5759 struct netdev_rx_queue *rx;
5763 rx = kcalloc(count, sizeof(struct netdev_rx_queue), GFP_KERNEL);
5769 for (i = 0; i < count; i++)
5775 static void netdev_init_one_queue(struct net_device *dev,
5776 struct netdev_queue *queue, void *_unused)
5778 /* Initialize queue lock */
5779 spin_lock_init(&queue->_xmit_lock);
5780 netdev_set_xmit_lockdep_class(&queue->_xmit_lock, dev->type);
5781 queue->xmit_lock_owner = -1;
5782 netdev_queue_numa_node_write(queue, NUMA_NO_NODE);
5785 dql_init(&queue->dql, HZ);
5789 static void netif_free_tx_queues(struct net_device *dev)
5791 if (is_vmalloc_addr(dev->_tx))
5797 static int netif_alloc_netdev_queues(struct net_device *dev)
5799 unsigned int count = dev->num_tx_queues;
5800 struct netdev_queue *tx;
5801 size_t sz = count * sizeof(*tx);
5803 BUG_ON(count < 1 || count > 0xffff);
5805 tx = kzalloc(sz, GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT);
5813 netdev_for_each_tx_queue(dev, netdev_init_one_queue, NULL);
5814 spin_lock_init(&dev->tx_global_lock);
5820 * register_netdevice - register a network device
5821 * @dev: device to register
5823 * Take a completed network device structure and add it to the kernel
5824 * interfaces. A %NETDEV_REGISTER message is sent to the netdev notifier
5825 * chain. 0 is returned on success. A negative errno code is returned
5826 * on a failure to set up the device, or if the name is a duplicate.
5828 * Callers must hold the rtnl semaphore. You may want
5829 * register_netdev() instead of this.
5832 * The locking appears insufficient to guarantee two parallel registers
5833 * will not get the same name.
5836 int register_netdevice(struct net_device *dev)
5839 struct net *net = dev_net(dev);
5841 BUG_ON(dev_boot_phase);
5846 /* When net_device's are persistent, this will be fatal. */
5847 BUG_ON(dev->reg_state != NETREG_UNINITIALIZED);
5850 spin_lock_init(&dev->addr_list_lock);
5851 netdev_set_addr_lockdep_class(dev);
5855 ret = dev_get_valid_name(net, dev, dev->name);
5859 /* Init, if this function is available */
5860 if (dev->netdev_ops->ndo_init) {
5861 ret = dev->netdev_ops->ndo_init(dev);
5869 if (((dev->hw_features | dev->features) &
5870 NETIF_F_HW_VLAN_CTAG_FILTER) &&
5871 (!dev->netdev_ops->ndo_vlan_rx_add_vid ||
5872 !dev->netdev_ops->ndo_vlan_rx_kill_vid)) {
5873 netdev_WARN(dev, "Buggy VLAN acceleration in driver!\n");
5880 dev->ifindex = dev_new_index(net);
5881 else if (__dev_get_by_index(net, dev->ifindex))
5884 if (dev->iflink == -1)
5885 dev->iflink = dev->ifindex;
5887 /* Transfer changeable features to wanted_features and enable
5888 * software offloads (GSO and GRO).
5890 dev->hw_features |= NETIF_F_SOFT_FEATURES;
5891 dev->features |= NETIF_F_SOFT_FEATURES;
5892 dev->wanted_features = dev->features & dev->hw_features;
5894 if (!(dev->flags & IFF_LOOPBACK)) {
5895 dev->hw_features |= NETIF_F_NOCACHE_COPY;
5898 /* Make NETIF_F_HIGHDMA inheritable to VLAN devices.
5900 dev->vlan_features |= NETIF_F_HIGHDMA;
5902 /* Make NETIF_F_SG inheritable to tunnel devices.
5904 dev->hw_enc_features |= NETIF_F_SG;
5906 /* Make NETIF_F_SG inheritable to MPLS.
5908 dev->mpls_features |= NETIF_F_SG;
5910 ret = call_netdevice_notifiers(NETDEV_POST_INIT, dev);
5911 ret = notifier_to_errno(ret);
5915 ret = netdev_register_kobject(dev);
5918 dev->reg_state = NETREG_REGISTERED;
5920 __netdev_update_features(dev);
5923 * Default initial state at registry is that the
5924 * device is present.
5927 set_bit(__LINK_STATE_PRESENT, &dev->state);
5929 linkwatch_init_dev(dev);
5931 dev_init_scheduler(dev);
5933 list_netdevice(dev);
5934 add_device_randomness(dev->dev_addr, dev->addr_len);
5936 /* If the device has permanent device address, driver should
5937 * set dev_addr and also addr_assign_type should be set to
5938 * NET_ADDR_PERM (default value).
5940 if (dev->addr_assign_type == NET_ADDR_PERM)
5941 memcpy(dev->perm_addr, dev->dev_addr, dev->addr_len);
5943 /* Notify protocols, that a new device appeared. */
5944 ret = call_netdevice_notifiers(NETDEV_REGISTER, dev);
5945 ret = notifier_to_errno(ret);
5947 rollback_registered(dev);
5948 dev->reg_state = NETREG_UNREGISTERED;
5951 * Prevent userspace races by waiting until the network
5952 * device is fully setup before sending notifications.
5954 if (!dev->rtnl_link_ops ||
5955 dev->rtnl_link_state == RTNL_LINK_INITIALIZED)
5956 rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U, GFP_KERNEL);
5962 if (dev->netdev_ops->ndo_uninit)
5963 dev->netdev_ops->ndo_uninit(dev);
5966 EXPORT_SYMBOL(register_netdevice);
5969 * init_dummy_netdev - init a dummy network device for NAPI
5970 * @dev: device to init
5972 * This takes a network device structure and initialize the minimum
5973 * amount of fields so it can be used to schedule NAPI polls without
5974 * registering a full blown interface. This is to be used by drivers
5975 * that need to tie several hardware interfaces to a single NAPI
5976 * poll scheduler due to HW limitations.
5978 int init_dummy_netdev(struct net_device *dev)
5980 /* Clear everything. Note we don't initialize spinlocks
5981 * are they aren't supposed to be taken by any of the
5982 * NAPI code and this dummy netdev is supposed to be
5983 * only ever used for NAPI polls
5985 memset(dev, 0, sizeof(struct net_device));
5987 /* make sure we BUG if trying to hit standard
5988 * register/unregister code path
5990 dev->reg_state = NETREG_DUMMY;
5992 /* NAPI wants this */
5993 INIT_LIST_HEAD(&dev->napi_list);
5995 /* a dummy interface is started by default */
5996 set_bit(__LINK_STATE_PRESENT, &dev->state);
5997 set_bit(__LINK_STATE_START, &dev->state);
5999 /* Note : We dont allocate pcpu_refcnt for dummy devices,
6000 * because users of this 'device' dont need to change
6006 EXPORT_SYMBOL_GPL(init_dummy_netdev);
6010 * register_netdev - register a network device
6011 * @dev: device to register
6013 * Take a completed network device structure and add it to the kernel
6014 * interfaces. A %NETDEV_REGISTER message is sent to the netdev notifier
6015 * chain. 0 is returned on success. A negative errno code is returned
6016 * on a failure to set up the device, or if the name is a duplicate.
6018 * This is a wrapper around register_netdevice that takes the rtnl semaphore
6019 * and expands the device name if you passed a format string to
6022 int register_netdev(struct net_device *dev)
6027 err = register_netdevice(dev);
6031 EXPORT_SYMBOL(register_netdev);
6033 int netdev_refcnt_read(const struct net_device *dev)
6037 for_each_possible_cpu(i)
6038 refcnt += *per_cpu_ptr(dev->pcpu_refcnt, i);
6041 EXPORT_SYMBOL(netdev_refcnt_read);
6044 * netdev_wait_allrefs - wait until all references are gone.
6045 * @dev: target net_device
6047 * This is called when unregistering network devices.
6049 * Any protocol or device that holds a reference should register
6050 * for netdevice notification, and cleanup and put back the
6051 * reference if they receive an UNREGISTER event.
6052 * We can get stuck here if buggy protocols don't correctly
6055 static void netdev_wait_allrefs(struct net_device *dev)
6057 unsigned long rebroadcast_time, warning_time;
6060 linkwatch_forget_dev(dev);
6062 rebroadcast_time = warning_time = jiffies;
6063 refcnt = netdev_refcnt_read(dev);
6065 while (refcnt != 0) {
6066 if (time_after(jiffies, rebroadcast_time + 1 * HZ)) {
6069 /* Rebroadcast unregister notification */
6070 call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
6076 call_netdevice_notifiers(NETDEV_UNREGISTER_FINAL, dev);
6077 if (test_bit(__LINK_STATE_LINKWATCH_PENDING,
6079 /* We must not have linkwatch events
6080 * pending on unregister. If this
6081 * happens, we simply run the queue
6082 * unscheduled, resulting in a noop
6085 linkwatch_run_queue();
6090 rebroadcast_time = jiffies;
6095 refcnt = netdev_refcnt_read(dev);
6097 if (time_after(jiffies, warning_time + 10 * HZ)) {
6098 pr_emerg("unregister_netdevice: waiting for %s to become free. Usage count = %d\n",
6100 warning_time = jiffies;
6109 * register_netdevice(x1);
6110 * register_netdevice(x2);
6112 * unregister_netdevice(y1);
6113 * unregister_netdevice(y2);
6119 * We are invoked by rtnl_unlock().
6120 * This allows us to deal with problems:
6121 * 1) We can delete sysfs objects which invoke hotplug
6122 * without deadlocking with linkwatch via keventd.
6123 * 2) Since we run with the RTNL semaphore not held, we can sleep
6124 * safely in order to wait for the netdev refcnt to drop to zero.
6126 * We must not return until all unregister events added during
6127 * the interval the lock was held have been completed.
6129 void netdev_run_todo(void)
6131 struct list_head list;
6133 /* Snapshot list, allow later requests */
6134 list_replace_init(&net_todo_list, &list);
6139 /* Wait for rcu callbacks to finish before next phase */
6140 if (!list_empty(&list))
6143 while (!list_empty(&list)) {
6144 struct net_device *dev
6145 = list_first_entry(&list, struct net_device, todo_list);
6146 list_del(&dev->todo_list);
6149 call_netdevice_notifiers(NETDEV_UNREGISTER_FINAL, dev);
6152 if (unlikely(dev->reg_state != NETREG_UNREGISTERING)) {
6153 pr_err("network todo '%s' but state %d\n",
6154 dev->name, dev->reg_state);
6159 dev->reg_state = NETREG_UNREGISTERED;
6161 on_each_cpu(flush_backlog, dev, 1);
6163 netdev_wait_allrefs(dev);
6166 BUG_ON(netdev_refcnt_read(dev));
6167 WARN_ON(rcu_access_pointer(dev->ip_ptr));
6168 WARN_ON(rcu_access_pointer(dev->ip6_ptr));
6169 WARN_ON(dev->dn_ptr);
6171 if (dev->destructor)
6172 dev->destructor(dev);
6174 /* Report a network device has been unregistered */
6176 dev_net(dev)->dev_unreg_count--;
6178 wake_up(&netdev_unregistering_wq);
6180 /* Free network device */
6181 kobject_put(&dev->dev.kobj);
6185 /* Convert net_device_stats to rtnl_link_stats64. They have the same
6186 * fields in the same order, with only the type differing.
6188 void netdev_stats_to_stats64(struct rtnl_link_stats64 *stats64,
6189 const struct net_device_stats *netdev_stats)
6191 #if BITS_PER_LONG == 64
6192 BUILD_BUG_ON(sizeof(*stats64) != sizeof(*netdev_stats));
6193 memcpy(stats64, netdev_stats, sizeof(*stats64));
6195 size_t i, n = sizeof(*stats64) / sizeof(u64);
6196 const unsigned long *src = (const unsigned long *)netdev_stats;
6197 u64 *dst = (u64 *)stats64;
6199 BUILD_BUG_ON(sizeof(*netdev_stats) / sizeof(unsigned long) !=
6200 sizeof(*stats64) / sizeof(u64));
6201 for (i = 0; i < n; i++)
6205 EXPORT_SYMBOL(netdev_stats_to_stats64);
6208 * dev_get_stats - get network device statistics
6209 * @dev: device to get statistics from
6210 * @storage: place to store stats
6212 * Get network statistics from device. Return @storage.
6213 * The device driver may provide its own method by setting
6214 * dev->netdev_ops->get_stats64 or dev->netdev_ops->get_stats;
6215 * otherwise the internal statistics structure is used.
6217 struct rtnl_link_stats64 *dev_get_stats(struct net_device *dev,
6218 struct rtnl_link_stats64 *storage)
6220 const struct net_device_ops *ops = dev->netdev_ops;
6222 if (ops->ndo_get_stats64) {
6223 memset(storage, 0, sizeof(*storage));
6224 ops->ndo_get_stats64(dev, storage);
6225 } else if (ops->ndo_get_stats) {
6226 netdev_stats_to_stats64(storage, ops->ndo_get_stats(dev));
6228 netdev_stats_to_stats64(storage, &dev->stats);
6230 storage->rx_dropped += atomic_long_read(&dev->rx_dropped);
6233 EXPORT_SYMBOL(dev_get_stats);
6235 struct netdev_queue *dev_ingress_queue_create(struct net_device *dev)
6237 struct netdev_queue *queue = dev_ingress_queue(dev);
6239 #ifdef CONFIG_NET_CLS_ACT
6242 queue = kzalloc(sizeof(*queue), GFP_KERNEL);
6245 netdev_init_one_queue(dev, queue, NULL);
6246 queue->qdisc = &noop_qdisc;
6247 queue->qdisc_sleeping = &noop_qdisc;
6248 rcu_assign_pointer(dev->ingress_queue, queue);
6253 static const struct ethtool_ops default_ethtool_ops;
6255 void netdev_set_default_ethtool_ops(struct net_device *dev,
6256 const struct ethtool_ops *ops)
6258 if (dev->ethtool_ops == &default_ethtool_ops)
6259 dev->ethtool_ops = ops;
6261 EXPORT_SYMBOL_GPL(netdev_set_default_ethtool_ops);
6263 void netdev_freemem(struct net_device *dev)
6265 char *addr = (char *)dev - dev->padded;
6267 if (is_vmalloc_addr(addr))
6274 * alloc_netdev_mqs - allocate network device
6275 * @sizeof_priv: size of private data to allocate space for
6276 * @name: device name format string
6277 * @setup: callback to initialize device
6278 * @txqs: the number of TX subqueues to allocate
6279 * @rxqs: the number of RX subqueues to allocate
6281 * Allocates a struct net_device with private data area for driver use
6282 * and performs basic initialization. Also allocates subquue structs
6283 * for each queue on the device.
6285 struct net_device *alloc_netdev_mqs(int sizeof_priv, const char *name,
6286 void (*setup)(struct net_device *),
6287 unsigned int txqs, unsigned int rxqs)
6289 struct net_device *dev;
6291 struct net_device *p;
6293 BUG_ON(strlen(name) >= sizeof(dev->name));
6296 pr_err("alloc_netdev: Unable to allocate device with zero queues\n");
6302 pr_err("alloc_netdev: Unable to allocate device with zero RX queues\n");
6307 alloc_size = sizeof(struct net_device);
6309 /* ensure 32-byte alignment of private area */
6310 alloc_size = ALIGN(alloc_size, NETDEV_ALIGN);
6311 alloc_size += sizeof_priv;
6313 /* ensure 32-byte alignment of whole construct */
6314 alloc_size += NETDEV_ALIGN - 1;
6316 p = kzalloc(alloc_size, GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT);
6318 p = vzalloc(alloc_size);
6322 dev = PTR_ALIGN(p, NETDEV_ALIGN);
6323 dev->padded = (char *)dev - (char *)p;
6325 dev->pcpu_refcnt = alloc_percpu(int);
6326 if (!dev->pcpu_refcnt)
6329 if (dev_addr_init(dev))
6335 dev_net_set(dev, &init_net);
6337 dev->gso_max_size = GSO_MAX_SIZE;
6338 dev->gso_max_segs = GSO_MAX_SEGS;
6340 INIT_LIST_HEAD(&dev->napi_list);
6341 INIT_LIST_HEAD(&dev->unreg_list);
6342 INIT_LIST_HEAD(&dev->close_list);
6343 INIT_LIST_HEAD(&dev->link_watch_list);
6344 INIT_LIST_HEAD(&dev->adj_list.upper);
6345 INIT_LIST_HEAD(&dev->adj_list.lower);
6346 INIT_LIST_HEAD(&dev->all_adj_list.upper);
6347 INIT_LIST_HEAD(&dev->all_adj_list.lower);
6348 dev->priv_flags = IFF_XMIT_DST_RELEASE;
6351 dev->num_tx_queues = txqs;
6352 dev->real_num_tx_queues = txqs;
6353 if (netif_alloc_netdev_queues(dev))
6357 dev->num_rx_queues = rxqs;
6358 dev->real_num_rx_queues = rxqs;
6359 if (netif_alloc_rx_queues(dev))
6363 strcpy(dev->name, name);
6364 dev->group = INIT_NETDEV_GROUP;
6365 if (!dev->ethtool_ops)
6366 dev->ethtool_ops = &default_ethtool_ops;
6374 free_percpu(dev->pcpu_refcnt);
6375 netif_free_tx_queues(dev);
6381 netdev_freemem(dev);
6384 EXPORT_SYMBOL(alloc_netdev_mqs);
6387 * free_netdev - free network device
6390 * This function does the last stage of destroying an allocated device
6391 * interface. The reference to the device object is released.
6392 * If this is the last reference then it will be freed.
6394 void free_netdev(struct net_device *dev)
6396 struct napi_struct *p, *n;
6398 release_net(dev_net(dev));
6400 netif_free_tx_queues(dev);
6405 kfree(rcu_dereference_protected(dev->ingress_queue, 1));
6407 /* Flush device addresses */
6408 dev_addr_flush(dev);
6410 list_for_each_entry_safe(p, n, &dev->napi_list, dev_list)
6413 free_percpu(dev->pcpu_refcnt);
6414 dev->pcpu_refcnt = NULL;
6416 /* Compatibility with error handling in drivers */
6417 if (dev->reg_state == NETREG_UNINITIALIZED) {
6418 netdev_freemem(dev);
6422 BUG_ON(dev->reg_state != NETREG_UNREGISTERED);
6423 dev->reg_state = NETREG_RELEASED;
6425 /* will free via device release */
6426 put_device(&dev->dev);
6428 EXPORT_SYMBOL(free_netdev);
6431 * synchronize_net - Synchronize with packet receive processing
6433 * Wait for packets currently being received to be done.
6434 * Does not block later packets from starting.
6436 void synchronize_net(void)
6439 if (rtnl_is_locked())
6440 synchronize_rcu_expedited();
6444 EXPORT_SYMBOL(synchronize_net);
6447 * unregister_netdevice_queue - remove device from the kernel
6451 * This function shuts down a device interface and removes it
6452 * from the kernel tables.
6453 * If head not NULL, device is queued to be unregistered later.
6455 * Callers must hold the rtnl semaphore. You may want
6456 * unregister_netdev() instead of this.
6459 void unregister_netdevice_queue(struct net_device *dev, struct list_head *head)
6464 list_move_tail(&dev->unreg_list, head);
6466 rollback_registered(dev);
6467 /* Finish processing unregister after unlock */
6471 EXPORT_SYMBOL(unregister_netdevice_queue);
6474 * unregister_netdevice_many - unregister many devices
6475 * @head: list of devices
6477 void unregister_netdevice_many(struct list_head *head)
6479 struct net_device *dev;
6481 if (!list_empty(head)) {
6482 rollback_registered_many(head);
6483 list_for_each_entry(dev, head, unreg_list)
6487 EXPORT_SYMBOL(unregister_netdevice_many);
6490 * unregister_netdev - remove device from the kernel
6493 * This function shuts down a device interface and removes it
6494 * from the kernel tables.
6496 * This is just a wrapper for unregister_netdevice that takes
6497 * the rtnl semaphore. In general you want to use this and not
6498 * unregister_netdevice.
6500 void unregister_netdev(struct net_device *dev)
6503 unregister_netdevice(dev);
6506 EXPORT_SYMBOL(unregister_netdev);
6509 * dev_change_net_namespace - move device to different nethost namespace
6511 * @net: network namespace
6512 * @pat: If not NULL name pattern to try if the current device name
6513 * is already taken in the destination network namespace.
6515 * This function shuts down a device interface and moves it
6516 * to a new network namespace. On success 0 is returned, on
6517 * a failure a netagive errno code is returned.
6519 * Callers must hold the rtnl semaphore.
6522 int dev_change_net_namespace(struct net_device *dev, struct net *net, const char *pat)
6528 /* Don't allow namespace local devices to be moved. */
6530 if (dev->features & NETIF_F_NETNS_LOCAL)
6533 /* Ensure the device has been registrered */
6534 if (dev->reg_state != NETREG_REGISTERED)
6537 /* Get out if there is nothing todo */
6539 if (net_eq(dev_net(dev), net))
6542 /* Pick the destination device name, and ensure
6543 * we can use it in the destination network namespace.
6546 if (__dev_get_by_name(net, dev->name)) {
6547 /* We get here if we can't use the current device name */
6550 if (dev_get_valid_name(net, dev, pat) < 0)
6555 * And now a mini version of register_netdevice unregister_netdevice.
6558 /* If device is running close it first. */
6561 /* And unlink it from device chain */
6563 unlist_netdevice(dev);
6567 /* Shutdown queueing discipline. */
6570 /* Notify protocols, that we are about to destroy
6571 this device. They should clean all the things.
6573 Note that dev->reg_state stays at NETREG_REGISTERED.
6574 This is wanted because this way 8021q and macvlan know
6575 the device is just moving and can keep their slaves up.
6577 call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
6579 call_netdevice_notifiers(NETDEV_UNREGISTER_FINAL, dev);
6580 rtmsg_ifinfo(RTM_DELLINK, dev, ~0U, GFP_KERNEL);
6583 * Flush the unicast and multicast chains
6588 /* Send a netdev-removed uevent to the old namespace */
6589 kobject_uevent(&dev->dev.kobj, KOBJ_REMOVE);
6591 /* Actually switch the network namespace */
6592 dev_net_set(dev, net);
6594 /* If there is an ifindex conflict assign a new one */
6595 if (__dev_get_by_index(net, dev->ifindex)) {
6596 int iflink = (dev->iflink == dev->ifindex);
6597 dev->ifindex = dev_new_index(net);
6599 dev->iflink = dev->ifindex;
6602 /* Send a netdev-add uevent to the new namespace */
6603 kobject_uevent(&dev->dev.kobj, KOBJ_ADD);
6605 /* Fixup kobjects */
6606 err = device_rename(&dev->dev, dev->name);
6609 /* Add the device back in the hashes */
6610 list_netdevice(dev);
6612 /* Notify protocols, that a new device appeared. */
6613 call_netdevice_notifiers(NETDEV_REGISTER, dev);
6616 * Prevent userspace races by waiting until the network
6617 * device is fully setup before sending notifications.
6619 rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U, GFP_KERNEL);
6626 EXPORT_SYMBOL_GPL(dev_change_net_namespace);
6628 static int dev_cpu_callback(struct notifier_block *nfb,
6629 unsigned long action,
6632 struct sk_buff **list_skb;
6633 struct sk_buff *skb;
6634 unsigned int cpu, oldcpu = (unsigned long)ocpu;
6635 struct softnet_data *sd, *oldsd;
6637 if (action != CPU_DEAD && action != CPU_DEAD_FROZEN)
6640 local_irq_disable();
6641 cpu = smp_processor_id();
6642 sd = &per_cpu(softnet_data, cpu);
6643 oldsd = &per_cpu(softnet_data, oldcpu);
6645 /* Find end of our completion_queue. */
6646 list_skb = &sd->completion_queue;
6648 list_skb = &(*list_skb)->next;
6649 /* Append completion queue from offline CPU. */
6650 *list_skb = oldsd->completion_queue;
6651 oldsd->completion_queue = NULL;
6653 /* Append output queue from offline CPU. */
6654 if (oldsd->output_queue) {
6655 *sd->output_queue_tailp = oldsd->output_queue;
6656 sd->output_queue_tailp = oldsd->output_queue_tailp;
6657 oldsd->output_queue = NULL;
6658 oldsd->output_queue_tailp = &oldsd->output_queue;
6660 /* Append NAPI poll list from offline CPU. */
6661 if (!list_empty(&oldsd->poll_list)) {
6662 list_splice_init(&oldsd->poll_list, &sd->poll_list);
6663 raise_softirq_irqoff(NET_RX_SOFTIRQ);
6666 raise_softirq_irqoff(NET_TX_SOFTIRQ);
6669 /* Process offline CPU's input_pkt_queue */
6670 while ((skb = __skb_dequeue(&oldsd->process_queue))) {
6671 netif_rx_internal(skb);
6672 input_queue_head_incr(oldsd);
6674 while ((skb = __skb_dequeue(&oldsd->input_pkt_queue))) {
6675 netif_rx_internal(skb);
6676 input_queue_head_incr(oldsd);
6684 * netdev_increment_features - increment feature set by one
6685 * @all: current feature set
6686 * @one: new feature set
6687 * @mask: mask feature set
6689 * Computes a new feature set after adding a device with feature set
6690 * @one to the master device with current feature set @all. Will not
6691 * enable anything that is off in @mask. Returns the new feature set.
6693 netdev_features_t netdev_increment_features(netdev_features_t all,
6694 netdev_features_t one, netdev_features_t mask)
6696 if (mask & NETIF_F_GEN_CSUM)
6697 mask |= NETIF_F_ALL_CSUM;
6698 mask |= NETIF_F_VLAN_CHALLENGED;
6700 all |= one & (NETIF_F_ONE_FOR_ALL|NETIF_F_ALL_CSUM) & mask;
6701 all &= one | ~NETIF_F_ALL_FOR_ALL;
6703 /* If one device supports hw checksumming, set for all. */
6704 if (all & NETIF_F_GEN_CSUM)
6705 all &= ~(NETIF_F_ALL_CSUM & ~NETIF_F_GEN_CSUM);
6709 EXPORT_SYMBOL(netdev_increment_features);
6711 static struct hlist_head * __net_init netdev_create_hash(void)
6714 struct hlist_head *hash;
6716 hash = kmalloc(sizeof(*hash) * NETDEV_HASHENTRIES, GFP_KERNEL);
6718 for (i = 0; i < NETDEV_HASHENTRIES; i++)
6719 INIT_HLIST_HEAD(&hash[i]);
6724 /* Initialize per network namespace state */
6725 static int __net_init netdev_init(struct net *net)
6727 if (net != &init_net)
6728 INIT_LIST_HEAD(&net->dev_base_head);
6730 net->dev_name_head = netdev_create_hash();
6731 if (net->dev_name_head == NULL)
6734 net->dev_index_head = netdev_create_hash();
6735 if (net->dev_index_head == NULL)
6741 kfree(net->dev_name_head);
6747 * netdev_drivername - network driver for the device
6748 * @dev: network device
6750 * Determine network driver for device.
6752 const char *netdev_drivername(const struct net_device *dev)
6754 const struct device_driver *driver;
6755 const struct device *parent;
6756 const char *empty = "";
6758 parent = dev->dev.parent;
6762 driver = parent->driver;
6763 if (driver && driver->name)
6764 return driver->name;
6768 static int __netdev_printk(const char *level, const struct net_device *dev,
6769 struct va_format *vaf)
6773 if (dev && dev->dev.parent) {
6774 r = dev_printk_emit(level[1] - '0',
6777 dev_driver_string(dev->dev.parent),
6778 dev_name(dev->dev.parent),
6779 netdev_name(dev), vaf);
6781 r = printk("%s%s: %pV", level, netdev_name(dev), vaf);
6783 r = printk("%s(NULL net_device): %pV", level, vaf);
6789 int netdev_printk(const char *level, const struct net_device *dev,
6790 const char *format, ...)
6792 struct va_format vaf;
6796 va_start(args, format);
6801 r = __netdev_printk(level, dev, &vaf);
6807 EXPORT_SYMBOL(netdev_printk);
6809 #define define_netdev_printk_level(func, level) \
6810 int func(const struct net_device *dev, const char *fmt, ...) \
6813 struct va_format vaf; \
6816 va_start(args, fmt); \
6821 r = __netdev_printk(level, dev, &vaf); \
6827 EXPORT_SYMBOL(func);
6829 define_netdev_printk_level(netdev_emerg, KERN_EMERG);
6830 define_netdev_printk_level(netdev_alert, KERN_ALERT);
6831 define_netdev_printk_level(netdev_crit, KERN_CRIT);
6832 define_netdev_printk_level(netdev_err, KERN_ERR);
6833 define_netdev_printk_level(netdev_warn, KERN_WARNING);
6834 define_netdev_printk_level(netdev_notice, KERN_NOTICE);
6835 define_netdev_printk_level(netdev_info, KERN_INFO);
6837 static void __net_exit netdev_exit(struct net *net)
6839 kfree(net->dev_name_head);
6840 kfree(net->dev_index_head);
6843 static struct pernet_operations __net_initdata netdev_net_ops = {
6844 .init = netdev_init,
6845 .exit = netdev_exit,
6848 static void __net_exit default_device_exit(struct net *net)
6850 struct net_device *dev, *aux;
6852 * Push all migratable network devices back to the
6853 * initial network namespace
6856 for_each_netdev_safe(net, dev, aux) {
6858 char fb_name[IFNAMSIZ];
6860 /* Ignore unmoveable devices (i.e. loopback) */
6861 if (dev->features & NETIF_F_NETNS_LOCAL)
6864 /* Leave virtual devices for the generic cleanup */
6865 if (dev->rtnl_link_ops)
6868 /* Push remaining network devices to init_net */
6869 snprintf(fb_name, IFNAMSIZ, "dev%d", dev->ifindex);
6870 err = dev_change_net_namespace(dev, &init_net, fb_name);
6872 pr_emerg("%s: failed to move %s to init_net: %d\n",
6873 __func__, dev->name, err);
6880 static void __net_exit rtnl_lock_unregistering(struct list_head *net_list)
6882 /* Return with the rtnl_lock held when there are no network
6883 * devices unregistering in any network namespace in net_list.
6890 prepare_to_wait(&netdev_unregistering_wq, &wait,
6891 TASK_UNINTERRUPTIBLE);
6892 unregistering = false;
6894 list_for_each_entry(net, net_list, exit_list) {
6895 if (net->dev_unreg_count > 0) {
6896 unregistering = true;
6905 finish_wait(&netdev_unregistering_wq, &wait);
6908 static void __net_exit default_device_exit_batch(struct list_head *net_list)
6910 /* At exit all network devices most be removed from a network
6911 * namespace. Do this in the reverse order of registration.
6912 * Do this across as many network namespaces as possible to
6913 * improve batching efficiency.
6915 struct net_device *dev;
6917 LIST_HEAD(dev_kill_list);
6919 /* To prevent network device cleanup code from dereferencing
6920 * loopback devices or network devices that have been freed
6921 * wait here for all pending unregistrations to complete,
6922 * before unregistring the loopback device and allowing the
6923 * network namespace be freed.
6925 * The netdev todo list containing all network devices
6926 * unregistrations that happen in default_device_exit_batch
6927 * will run in the rtnl_unlock() at the end of
6928 * default_device_exit_batch.
6930 rtnl_lock_unregistering(net_list);
6931 list_for_each_entry(net, net_list, exit_list) {
6932 for_each_netdev_reverse(net, dev) {
6933 if (dev->rtnl_link_ops)
6934 dev->rtnl_link_ops->dellink(dev, &dev_kill_list);
6936 unregister_netdevice_queue(dev, &dev_kill_list);
6939 unregister_netdevice_many(&dev_kill_list);
6940 list_del(&dev_kill_list);
6944 static struct pernet_operations __net_initdata default_device_ops = {
6945 .exit = default_device_exit,
6946 .exit_batch = default_device_exit_batch,
6950 * Initialize the DEV module. At boot time this walks the device list and
6951 * unhooks any devices that fail to initialise (normally hardware not
6952 * present) and leaves us with a valid list of present and active devices.
6957 * This is called single threaded during boot, so no need
6958 * to take the rtnl semaphore.
6960 static int __init net_dev_init(void)
6962 int i, rc = -ENOMEM;
6964 BUG_ON(!dev_boot_phase);
6966 if (dev_proc_init())
6969 if (netdev_kobject_init())
6972 INIT_LIST_HEAD(&ptype_all);
6973 for (i = 0; i < PTYPE_HASH_SIZE; i++)
6974 INIT_LIST_HEAD(&ptype_base[i]);
6976 INIT_LIST_HEAD(&offload_base);
6978 if (register_pernet_subsys(&netdev_net_ops))
6982 * Initialise the packet receive queues.
6985 for_each_possible_cpu(i) {
6986 struct softnet_data *sd = &per_cpu(softnet_data, i);
6988 memset(sd, 0, sizeof(*sd));
6989 skb_queue_head_init(&sd->input_pkt_queue);
6990 skb_queue_head_init(&sd->process_queue);
6991 sd->completion_queue = NULL;
6992 INIT_LIST_HEAD(&sd->poll_list);
6993 sd->output_queue = NULL;
6994 sd->output_queue_tailp = &sd->output_queue;
6996 sd->csd.func = rps_trigger_softirq;
7002 sd->backlog.poll = process_backlog;
7003 sd->backlog.weight = weight_p;
7004 sd->backlog.gro_list = NULL;
7005 sd->backlog.gro_count = 0;
7007 #ifdef CONFIG_NET_FLOW_LIMIT
7008 sd->flow_limit = NULL;
7014 /* The loopback device is special if any other network devices
7015 * is present in a network namespace the loopback device must
7016 * be present. Since we now dynamically allocate and free the
7017 * loopback device ensure this invariant is maintained by
7018 * keeping the loopback device as the first device on the
7019 * list of network devices. Ensuring the loopback devices
7020 * is the first device that appears and the last network device
7023 if (register_pernet_device(&loopback_net_ops))
7026 if (register_pernet_device(&default_device_ops))
7029 open_softirq(NET_TX_SOFTIRQ, net_tx_action);
7030 open_softirq(NET_RX_SOFTIRQ, net_rx_action);
7032 hotcpu_notifier(dev_cpu_callback, 0);
7039 subsys_initcall(net_dev_init);