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 <linux/bpf.h>
98 #include <net/net_namespace.h>
100 #include <net/busy_poll.h>
101 #include <linux/rtnetlink.h>
102 #include <linux/stat.h>
104 #include <net/dst_metadata.h>
105 #include <net/pkt_sched.h>
106 #include <net/checksum.h>
107 #include <net/xfrm.h>
108 #include <linux/highmem.h>
109 #include <linux/init.h>
110 #include <linux/module.h>
111 #include <linux/netpoll.h>
112 #include <linux/rcupdate.h>
113 #include <linux/delay.h>
114 #include <net/iw_handler.h>
115 #include <asm/current.h>
116 #include <linux/audit.h>
117 #include <linux/dmaengine.h>
118 #include <linux/err.h>
119 #include <linux/ctype.h>
120 #include <linux/if_arp.h>
121 #include <linux/if_vlan.h>
122 #include <linux/ip.h>
124 #include <net/mpls.h>
125 #include <linux/ipv6.h>
126 #include <linux/in.h>
127 #include <linux/jhash.h>
128 #include <linux/random.h>
129 #include <trace/events/napi.h>
130 #include <trace/events/net.h>
131 #include <trace/events/skb.h>
132 #include <linux/pci.h>
133 #include <linux/inetdevice.h>
134 #include <linux/cpu_rmap.h>
135 #include <linux/static_key.h>
136 #include <linux/hashtable.h>
137 #include <linux/vmalloc.h>
138 #include <linux/if_macvlan.h>
139 #include <linux/errqueue.h>
140 #include <linux/hrtimer.h>
141 #include <linux/netfilter_ingress.h>
142 #include <linux/sctp.h>
143 #include <linux/crash_dump.h>
145 #include "net-sysfs.h"
147 /* Instead of increasing this, you should create a hash table. */
148 #define MAX_GRO_SKBS 8
150 /* This should be increased if a protocol with a bigger head is added. */
151 #define GRO_MAX_HEAD (MAX_HEADER + 128)
153 static DEFINE_SPINLOCK(ptype_lock);
154 static DEFINE_SPINLOCK(offload_lock);
155 struct list_head ptype_base[PTYPE_HASH_SIZE] __read_mostly;
156 struct list_head ptype_all __read_mostly; /* Taps */
157 static struct list_head offload_base __read_mostly;
159 static int netif_rx_internal(struct sk_buff *skb);
160 static int call_netdevice_notifiers_info(unsigned long val,
161 struct net_device *dev,
162 struct netdev_notifier_info *info);
165 * The @dev_base_head list is protected by @dev_base_lock and the rtnl
168 * Pure readers hold dev_base_lock for reading, or rcu_read_lock()
170 * Writers must hold the rtnl semaphore while they loop through the
171 * dev_base_head list, and hold dev_base_lock for writing when they do the
172 * actual updates. This allows pure readers to access the list even
173 * while a writer is preparing to update it.
175 * To put it another way, dev_base_lock is held for writing only to
176 * protect against pure readers; the rtnl semaphore provides the
177 * protection against other writers.
179 * See, for example usages, register_netdevice() and
180 * unregister_netdevice(), which must be called with the rtnl
183 DEFINE_RWLOCK(dev_base_lock);
184 EXPORT_SYMBOL(dev_base_lock);
186 /* protects napi_hash addition/deletion and napi_gen_id */
187 static DEFINE_SPINLOCK(napi_hash_lock);
189 static unsigned int napi_gen_id = NR_CPUS;
190 static DEFINE_READ_MOSTLY_HASHTABLE(napi_hash, 8);
192 static seqcount_t devnet_rename_seq;
194 static inline void dev_base_seq_inc(struct net *net)
196 while (++net->dev_base_seq == 0);
199 static inline struct hlist_head *dev_name_hash(struct net *net, const char *name)
201 unsigned int hash = full_name_hash(net, name, strnlen(name, IFNAMSIZ));
203 return &net->dev_name_head[hash_32(hash, NETDEV_HASHBITS)];
206 static inline struct hlist_head *dev_index_hash(struct net *net, int ifindex)
208 return &net->dev_index_head[ifindex & (NETDEV_HASHENTRIES - 1)];
211 static inline void rps_lock(struct softnet_data *sd)
214 spin_lock(&sd->input_pkt_queue.lock);
218 static inline void rps_unlock(struct softnet_data *sd)
221 spin_unlock(&sd->input_pkt_queue.lock);
225 /* Device list insertion */
226 static void list_netdevice(struct net_device *dev)
228 struct net *net = dev_net(dev);
232 write_lock_bh(&dev_base_lock);
233 list_add_tail_rcu(&dev->dev_list, &net->dev_base_head);
234 hlist_add_head_rcu(&dev->name_hlist, dev_name_hash(net, dev->name));
235 hlist_add_head_rcu(&dev->index_hlist,
236 dev_index_hash(net, dev->ifindex));
237 write_unlock_bh(&dev_base_lock);
239 dev_base_seq_inc(net);
242 /* Device list removal
243 * caller must respect a RCU grace period before freeing/reusing dev
245 static void unlist_netdevice(struct net_device *dev)
249 /* Unlink dev from the device chain */
250 write_lock_bh(&dev_base_lock);
251 list_del_rcu(&dev->dev_list);
252 hlist_del_rcu(&dev->name_hlist);
253 hlist_del_rcu(&dev->index_hlist);
254 write_unlock_bh(&dev_base_lock);
256 dev_base_seq_inc(dev_net(dev));
263 static RAW_NOTIFIER_HEAD(netdev_chain);
266 * Device drivers call our routines to queue packets here. We empty the
267 * queue in the local softnet handler.
270 DEFINE_PER_CPU_ALIGNED(struct softnet_data, softnet_data);
271 EXPORT_PER_CPU_SYMBOL(softnet_data);
273 #ifdef CONFIG_LOCKDEP
275 * register_netdevice() inits txq->_xmit_lock and sets lockdep class
276 * according to dev->type
278 static const unsigned short netdev_lock_type[] =
279 {ARPHRD_NETROM, ARPHRD_ETHER, ARPHRD_EETHER, ARPHRD_AX25,
280 ARPHRD_PRONET, ARPHRD_CHAOS, ARPHRD_IEEE802, ARPHRD_ARCNET,
281 ARPHRD_APPLETLK, ARPHRD_DLCI, ARPHRD_ATM, ARPHRD_METRICOM,
282 ARPHRD_IEEE1394, ARPHRD_EUI64, ARPHRD_INFINIBAND, ARPHRD_SLIP,
283 ARPHRD_CSLIP, ARPHRD_SLIP6, ARPHRD_CSLIP6, ARPHRD_RSRVD,
284 ARPHRD_ADAPT, ARPHRD_ROSE, ARPHRD_X25, ARPHRD_HWX25,
285 ARPHRD_PPP, ARPHRD_CISCO, ARPHRD_LAPB, ARPHRD_DDCMP,
286 ARPHRD_RAWHDLC, ARPHRD_TUNNEL, ARPHRD_TUNNEL6, ARPHRD_FRAD,
287 ARPHRD_SKIP, ARPHRD_LOOPBACK, ARPHRD_LOCALTLK, ARPHRD_FDDI,
288 ARPHRD_BIF, ARPHRD_SIT, ARPHRD_IPDDP, ARPHRD_IPGRE,
289 ARPHRD_PIMREG, ARPHRD_HIPPI, ARPHRD_ASH, ARPHRD_ECONET,
290 ARPHRD_IRDA, ARPHRD_FCPP, ARPHRD_FCAL, ARPHRD_FCPL,
291 ARPHRD_FCFABRIC, ARPHRD_IEEE80211, ARPHRD_IEEE80211_PRISM,
292 ARPHRD_IEEE80211_RADIOTAP, ARPHRD_PHONET, ARPHRD_PHONET_PIPE,
293 ARPHRD_IEEE802154, ARPHRD_VOID, ARPHRD_NONE};
295 static const char *const netdev_lock_name[] =
296 {"_xmit_NETROM", "_xmit_ETHER", "_xmit_EETHER", "_xmit_AX25",
297 "_xmit_PRONET", "_xmit_CHAOS", "_xmit_IEEE802", "_xmit_ARCNET",
298 "_xmit_APPLETLK", "_xmit_DLCI", "_xmit_ATM", "_xmit_METRICOM",
299 "_xmit_IEEE1394", "_xmit_EUI64", "_xmit_INFINIBAND", "_xmit_SLIP",
300 "_xmit_CSLIP", "_xmit_SLIP6", "_xmit_CSLIP6", "_xmit_RSRVD",
301 "_xmit_ADAPT", "_xmit_ROSE", "_xmit_X25", "_xmit_HWX25",
302 "_xmit_PPP", "_xmit_CISCO", "_xmit_LAPB", "_xmit_DDCMP",
303 "_xmit_RAWHDLC", "_xmit_TUNNEL", "_xmit_TUNNEL6", "_xmit_FRAD",
304 "_xmit_SKIP", "_xmit_LOOPBACK", "_xmit_LOCALTLK", "_xmit_FDDI",
305 "_xmit_BIF", "_xmit_SIT", "_xmit_IPDDP", "_xmit_IPGRE",
306 "_xmit_PIMREG", "_xmit_HIPPI", "_xmit_ASH", "_xmit_ECONET",
307 "_xmit_IRDA", "_xmit_FCPP", "_xmit_FCAL", "_xmit_FCPL",
308 "_xmit_FCFABRIC", "_xmit_IEEE80211", "_xmit_IEEE80211_PRISM",
309 "_xmit_IEEE80211_RADIOTAP", "_xmit_PHONET", "_xmit_PHONET_PIPE",
310 "_xmit_IEEE802154", "_xmit_VOID", "_xmit_NONE"};
312 static struct lock_class_key netdev_xmit_lock_key[ARRAY_SIZE(netdev_lock_type)];
313 static struct lock_class_key netdev_addr_lock_key[ARRAY_SIZE(netdev_lock_type)];
315 static inline unsigned short netdev_lock_pos(unsigned short dev_type)
319 for (i = 0; i < ARRAY_SIZE(netdev_lock_type); i++)
320 if (netdev_lock_type[i] == dev_type)
322 /* the last key is used by default */
323 return ARRAY_SIZE(netdev_lock_type) - 1;
326 static inline void netdev_set_xmit_lockdep_class(spinlock_t *lock,
327 unsigned short dev_type)
331 i = netdev_lock_pos(dev_type);
332 lockdep_set_class_and_name(lock, &netdev_xmit_lock_key[i],
333 netdev_lock_name[i]);
336 static inline void netdev_set_addr_lockdep_class(struct net_device *dev)
340 i = netdev_lock_pos(dev->type);
341 lockdep_set_class_and_name(&dev->addr_list_lock,
342 &netdev_addr_lock_key[i],
343 netdev_lock_name[i]);
346 static inline void netdev_set_xmit_lockdep_class(spinlock_t *lock,
347 unsigned short dev_type)
350 static inline void netdev_set_addr_lockdep_class(struct net_device *dev)
355 /*******************************************************************************
357 Protocol management and registration routines
359 *******************************************************************************/
362 * Add a protocol ID to the list. Now that the input handler is
363 * smarter we can dispense with all the messy stuff that used to be
366 * BEWARE!!! Protocol handlers, mangling input packets,
367 * MUST BE last in hash buckets and checking protocol handlers
368 * MUST start from promiscuous ptype_all chain in net_bh.
369 * It is true now, do not change it.
370 * Explanation follows: if protocol handler, mangling packet, will
371 * be the first on list, it is not able to sense, that packet
372 * is cloned and should be copied-on-write, so that it will
373 * change it and subsequent readers will get broken packet.
377 static inline struct list_head *ptype_head(const struct packet_type *pt)
379 if (pt->type == htons(ETH_P_ALL))
380 return pt->dev ? &pt->dev->ptype_all : &ptype_all;
382 return pt->dev ? &pt->dev->ptype_specific :
383 &ptype_base[ntohs(pt->type) & PTYPE_HASH_MASK];
387 * dev_add_pack - add packet handler
388 * @pt: packet type declaration
390 * Add a protocol handler to the networking stack. The passed &packet_type
391 * is linked into kernel lists and may not be freed until it has been
392 * removed from the kernel lists.
394 * This call does not sleep therefore it can not
395 * guarantee all CPU's that are in middle of receiving packets
396 * will see the new packet type (until the next received packet).
399 void dev_add_pack(struct packet_type *pt)
401 struct list_head *head = ptype_head(pt);
403 spin_lock(&ptype_lock);
404 list_add_rcu(&pt->list, head);
405 spin_unlock(&ptype_lock);
407 EXPORT_SYMBOL(dev_add_pack);
410 * __dev_remove_pack - remove packet handler
411 * @pt: packet type declaration
413 * Remove a protocol handler that was previously added to the kernel
414 * protocol handlers by dev_add_pack(). The passed &packet_type is removed
415 * from the kernel lists and can be freed or reused once this function
418 * The packet type might still be in use by receivers
419 * and must not be freed until after all the CPU's have gone
420 * through a quiescent state.
422 void __dev_remove_pack(struct packet_type *pt)
424 struct list_head *head = ptype_head(pt);
425 struct packet_type *pt1;
427 spin_lock(&ptype_lock);
429 list_for_each_entry(pt1, head, list) {
431 list_del_rcu(&pt->list);
436 pr_warn("dev_remove_pack: %p not found\n", pt);
438 spin_unlock(&ptype_lock);
440 EXPORT_SYMBOL(__dev_remove_pack);
443 * dev_remove_pack - remove packet handler
444 * @pt: packet type declaration
446 * Remove a protocol handler that was previously added to the kernel
447 * protocol handlers by dev_add_pack(). The passed &packet_type is removed
448 * from the kernel lists and can be freed or reused once this function
451 * This call sleeps to guarantee that no CPU is looking at the packet
454 void dev_remove_pack(struct packet_type *pt)
456 __dev_remove_pack(pt);
460 EXPORT_SYMBOL(dev_remove_pack);
464 * dev_add_offload - register offload handlers
465 * @po: protocol offload declaration
467 * Add protocol offload handlers to the networking stack. The passed
468 * &proto_offload is linked into kernel lists and may not be freed until
469 * it has been removed from the kernel lists.
471 * This call does not sleep therefore it can not
472 * guarantee all CPU's that are in middle of receiving packets
473 * will see the new offload handlers (until the next received packet).
475 void dev_add_offload(struct packet_offload *po)
477 struct packet_offload *elem;
479 spin_lock(&offload_lock);
480 list_for_each_entry(elem, &offload_base, list) {
481 if (po->priority < elem->priority)
484 list_add_rcu(&po->list, elem->list.prev);
485 spin_unlock(&offload_lock);
487 EXPORT_SYMBOL(dev_add_offload);
490 * __dev_remove_offload - remove offload handler
491 * @po: packet offload declaration
493 * Remove a protocol offload handler that was previously added to the
494 * kernel offload handlers by dev_add_offload(). The passed &offload_type
495 * is removed from the kernel lists and can be freed or reused once this
498 * The packet type might still be in use by receivers
499 * and must not be freed until after all the CPU's have gone
500 * through a quiescent state.
502 static void __dev_remove_offload(struct packet_offload *po)
504 struct list_head *head = &offload_base;
505 struct packet_offload *po1;
507 spin_lock(&offload_lock);
509 list_for_each_entry(po1, head, list) {
511 list_del_rcu(&po->list);
516 pr_warn("dev_remove_offload: %p not found\n", po);
518 spin_unlock(&offload_lock);
522 * dev_remove_offload - remove packet offload handler
523 * @po: packet offload declaration
525 * Remove a packet offload handler that was previously added to the kernel
526 * offload handlers by dev_add_offload(). The passed &offload_type is
527 * removed from the kernel lists and can be freed or reused once this
530 * This call sleeps to guarantee that no CPU is looking at the packet
533 void dev_remove_offload(struct packet_offload *po)
535 __dev_remove_offload(po);
539 EXPORT_SYMBOL(dev_remove_offload);
541 /******************************************************************************
543 Device Boot-time Settings Routines
545 *******************************************************************************/
547 /* Boot time configuration table */
548 static struct netdev_boot_setup dev_boot_setup[NETDEV_BOOT_SETUP_MAX];
551 * netdev_boot_setup_add - add new setup entry
552 * @name: name of the device
553 * @map: configured settings for the device
555 * Adds new setup entry to the dev_boot_setup list. The function
556 * returns 0 on error and 1 on success. This is a generic routine to
559 static int netdev_boot_setup_add(char *name, struct ifmap *map)
561 struct netdev_boot_setup *s;
565 for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++) {
566 if (s[i].name[0] == '\0' || s[i].name[0] == ' ') {
567 memset(s[i].name, 0, sizeof(s[i].name));
568 strlcpy(s[i].name, name, IFNAMSIZ);
569 memcpy(&s[i].map, map, sizeof(s[i].map));
574 return i >= NETDEV_BOOT_SETUP_MAX ? 0 : 1;
578 * netdev_boot_setup_check - check boot time settings
579 * @dev: the netdevice
581 * Check boot time settings for the device.
582 * The found settings are set for the device to be used
583 * later in the device probing.
584 * Returns 0 if no settings found, 1 if they are.
586 int netdev_boot_setup_check(struct net_device *dev)
588 struct netdev_boot_setup *s = dev_boot_setup;
591 for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++) {
592 if (s[i].name[0] != '\0' && s[i].name[0] != ' ' &&
593 !strcmp(dev->name, s[i].name)) {
594 dev->irq = s[i].map.irq;
595 dev->base_addr = s[i].map.base_addr;
596 dev->mem_start = s[i].map.mem_start;
597 dev->mem_end = s[i].map.mem_end;
603 EXPORT_SYMBOL(netdev_boot_setup_check);
607 * netdev_boot_base - get address from boot time settings
608 * @prefix: prefix for network device
609 * @unit: id for network device
611 * Check boot time settings for the base address of device.
612 * The found settings are set for the device to be used
613 * later in the device probing.
614 * Returns 0 if no settings found.
616 unsigned long netdev_boot_base(const char *prefix, int unit)
618 const struct netdev_boot_setup *s = dev_boot_setup;
622 sprintf(name, "%s%d", prefix, unit);
625 * If device already registered then return base of 1
626 * to indicate not to probe for this interface
628 if (__dev_get_by_name(&init_net, name))
631 for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++)
632 if (!strcmp(name, s[i].name))
633 return s[i].map.base_addr;
638 * Saves at boot time configured settings for any netdevice.
640 int __init netdev_boot_setup(char *str)
645 str = get_options(str, ARRAY_SIZE(ints), ints);
650 memset(&map, 0, sizeof(map));
654 map.base_addr = ints[2];
656 map.mem_start = ints[3];
658 map.mem_end = ints[4];
660 /* Add new entry to the list */
661 return netdev_boot_setup_add(str, &map);
664 __setup("netdev=", netdev_boot_setup);
666 /*******************************************************************************
668 Device Interface Subroutines
670 *******************************************************************************/
673 * dev_get_iflink - get 'iflink' value of a interface
674 * @dev: targeted interface
676 * Indicates the ifindex the interface is linked to.
677 * Physical interfaces have the same 'ifindex' and 'iflink' values.
680 int dev_get_iflink(const struct net_device *dev)
682 if (dev->netdev_ops && dev->netdev_ops->ndo_get_iflink)
683 return dev->netdev_ops->ndo_get_iflink(dev);
687 EXPORT_SYMBOL(dev_get_iflink);
690 * dev_fill_metadata_dst - Retrieve tunnel egress information.
691 * @dev: targeted interface
694 * For better visibility of tunnel traffic OVS needs to retrieve
695 * egress tunnel information for a packet. Following API allows
696 * user to get this info.
698 int dev_fill_metadata_dst(struct net_device *dev, struct sk_buff *skb)
700 struct ip_tunnel_info *info;
702 if (!dev->netdev_ops || !dev->netdev_ops->ndo_fill_metadata_dst)
705 info = skb_tunnel_info_unclone(skb);
708 if (unlikely(!(info->mode & IP_TUNNEL_INFO_TX)))
711 return dev->netdev_ops->ndo_fill_metadata_dst(dev, skb);
713 EXPORT_SYMBOL_GPL(dev_fill_metadata_dst);
716 * __dev_get_by_name - find a device by its name
717 * @net: the applicable net namespace
718 * @name: name to find
720 * Find an interface by name. Must be called under RTNL semaphore
721 * or @dev_base_lock. If the name is found a pointer to the device
722 * is returned. If the name is not found then %NULL is returned. The
723 * reference counters are not incremented so the caller must be
724 * careful with locks.
727 struct net_device *__dev_get_by_name(struct net *net, const char *name)
729 struct net_device *dev;
730 struct hlist_head *head = dev_name_hash(net, name);
732 hlist_for_each_entry(dev, head, name_hlist)
733 if (!strncmp(dev->name, name, IFNAMSIZ))
738 EXPORT_SYMBOL(__dev_get_by_name);
741 * dev_get_by_name_rcu - find a device by its name
742 * @net: the applicable net namespace
743 * @name: name to find
745 * Find an interface by name.
746 * If the name is found a pointer to the device is returned.
747 * If the name is not found then %NULL is returned.
748 * The reference counters are not incremented so the caller must be
749 * careful with locks. The caller must hold RCU lock.
752 struct net_device *dev_get_by_name_rcu(struct net *net, const char *name)
754 struct net_device *dev;
755 struct hlist_head *head = dev_name_hash(net, name);
757 hlist_for_each_entry_rcu(dev, head, name_hlist)
758 if (!strncmp(dev->name, name, IFNAMSIZ))
763 EXPORT_SYMBOL(dev_get_by_name_rcu);
766 * dev_get_by_name - find a device by its name
767 * @net: the applicable net namespace
768 * @name: name to find
770 * Find an interface by name. This can be called from any
771 * context and does its own locking. The returned handle has
772 * the usage count incremented and the caller must use dev_put() to
773 * release it when it is no longer needed. %NULL is returned if no
774 * matching device is found.
777 struct net_device *dev_get_by_name(struct net *net, const char *name)
779 struct net_device *dev;
782 dev = dev_get_by_name_rcu(net, name);
788 EXPORT_SYMBOL(dev_get_by_name);
791 * __dev_get_by_index - find a device by its ifindex
792 * @net: the applicable net namespace
793 * @ifindex: index of device
795 * Search for an interface by index. Returns %NULL if the device
796 * is not found or a pointer to the device. The device has not
797 * had its reference counter increased so the caller must be careful
798 * about locking. The caller must hold either the RTNL semaphore
802 struct net_device *__dev_get_by_index(struct net *net, int ifindex)
804 struct net_device *dev;
805 struct hlist_head *head = dev_index_hash(net, ifindex);
807 hlist_for_each_entry(dev, head, index_hlist)
808 if (dev->ifindex == ifindex)
813 EXPORT_SYMBOL(__dev_get_by_index);
816 * dev_get_by_index_rcu - find a device by its ifindex
817 * @net: the applicable net namespace
818 * @ifindex: index of device
820 * Search for an interface by index. Returns %NULL if the device
821 * is not found or a pointer to the device. The device has not
822 * had its reference counter increased so the caller must be careful
823 * about locking. The caller must hold RCU lock.
826 struct net_device *dev_get_by_index_rcu(struct net *net, int ifindex)
828 struct net_device *dev;
829 struct hlist_head *head = dev_index_hash(net, ifindex);
831 hlist_for_each_entry_rcu(dev, head, index_hlist)
832 if (dev->ifindex == ifindex)
837 EXPORT_SYMBOL(dev_get_by_index_rcu);
841 * dev_get_by_index - find a device by its ifindex
842 * @net: the applicable net namespace
843 * @ifindex: index of device
845 * Search for an interface by index. Returns NULL if the device
846 * is not found or a pointer to the device. The device returned has
847 * had a reference added and the pointer is safe until the user calls
848 * dev_put to indicate they have finished with it.
851 struct net_device *dev_get_by_index(struct net *net, int ifindex)
853 struct net_device *dev;
856 dev = dev_get_by_index_rcu(net, ifindex);
862 EXPORT_SYMBOL(dev_get_by_index);
865 * netdev_get_name - get a netdevice name, knowing its ifindex.
866 * @net: network namespace
867 * @name: a pointer to the buffer where the name will be stored.
868 * @ifindex: the ifindex of the interface to get the name from.
870 * The use of raw_seqcount_begin() and cond_resched() before
871 * retrying is required as we want to give the writers a chance
872 * to complete when CONFIG_PREEMPT is not set.
874 int netdev_get_name(struct net *net, char *name, int ifindex)
876 struct net_device *dev;
880 seq = raw_seqcount_begin(&devnet_rename_seq);
882 dev = dev_get_by_index_rcu(net, ifindex);
888 strcpy(name, dev->name);
890 if (read_seqcount_retry(&devnet_rename_seq, seq)) {
899 * dev_getbyhwaddr_rcu - find a device by its hardware address
900 * @net: the applicable net namespace
901 * @type: media type of device
902 * @ha: hardware address
904 * Search for an interface by MAC address. Returns NULL if the device
905 * is not found or a pointer to the device.
906 * The caller must hold RCU or RTNL.
907 * The returned device has not had its ref count increased
908 * and the caller must therefore be careful about locking
912 struct net_device *dev_getbyhwaddr_rcu(struct net *net, unsigned short type,
915 struct net_device *dev;
917 for_each_netdev_rcu(net, dev)
918 if (dev->type == type &&
919 !memcmp(dev->dev_addr, ha, dev->addr_len))
924 EXPORT_SYMBOL(dev_getbyhwaddr_rcu);
926 struct net_device *__dev_getfirstbyhwtype(struct net *net, unsigned short type)
928 struct net_device *dev;
931 for_each_netdev(net, dev)
932 if (dev->type == type)
937 EXPORT_SYMBOL(__dev_getfirstbyhwtype);
939 struct net_device *dev_getfirstbyhwtype(struct net *net, unsigned short type)
941 struct net_device *dev, *ret = NULL;
944 for_each_netdev_rcu(net, dev)
945 if (dev->type == type) {
953 EXPORT_SYMBOL(dev_getfirstbyhwtype);
956 * __dev_get_by_flags - find any device with given flags
957 * @net: the applicable net namespace
958 * @if_flags: IFF_* values
959 * @mask: bitmask of bits in if_flags to check
961 * Search for any interface with the given flags. Returns NULL if a device
962 * is not found or a pointer to the device. Must be called inside
963 * rtnl_lock(), and result refcount is unchanged.
966 struct net_device *__dev_get_by_flags(struct net *net, unsigned short if_flags,
969 struct net_device *dev, *ret;
974 for_each_netdev(net, dev) {
975 if (((dev->flags ^ if_flags) & mask) == 0) {
982 EXPORT_SYMBOL(__dev_get_by_flags);
985 * dev_valid_name - check if name is okay for network device
988 * Network device names need to be valid file names to
989 * to allow sysfs to work. We also disallow any kind of
992 bool dev_valid_name(const char *name)
996 if (strlen(name) >= IFNAMSIZ)
998 if (!strcmp(name, ".") || !strcmp(name, ".."))
1002 if (*name == '/' || *name == ':' || isspace(*name))
1008 EXPORT_SYMBOL(dev_valid_name);
1011 * __dev_alloc_name - allocate a name for a device
1012 * @net: network namespace to allocate the device name in
1013 * @name: name format string
1014 * @buf: scratch buffer and result name string
1016 * Passed a format string - eg "lt%d" it will try and find a suitable
1017 * id. It scans list of devices to build up a free map, then chooses
1018 * the first empty slot. The caller must hold the dev_base or rtnl lock
1019 * while allocating the name and adding the device in order to avoid
1021 * Limited to bits_per_byte * page size devices (ie 32K on most platforms).
1022 * Returns the number of the unit assigned or a negative errno code.
1025 static int __dev_alloc_name(struct net *net, const char *name, char *buf)
1029 const int max_netdevices = 8*PAGE_SIZE;
1030 unsigned long *inuse;
1031 struct net_device *d;
1033 p = strnchr(name, IFNAMSIZ-1, '%');
1036 * Verify the string as this thing may have come from
1037 * the user. There must be either one "%d" and no other "%"
1040 if (p[1] != 'd' || strchr(p + 2, '%'))
1043 /* Use one page as a bit array of possible slots */
1044 inuse = (unsigned long *) get_zeroed_page(GFP_ATOMIC);
1048 for_each_netdev(net, d) {
1049 if (!sscanf(d->name, name, &i))
1051 if (i < 0 || i >= max_netdevices)
1054 /* avoid cases where sscanf is not exact inverse of printf */
1055 snprintf(buf, IFNAMSIZ, name, i);
1056 if (!strncmp(buf, d->name, IFNAMSIZ))
1060 i = find_first_zero_bit(inuse, max_netdevices);
1061 free_page((unsigned long) inuse);
1065 snprintf(buf, IFNAMSIZ, name, i);
1066 if (!__dev_get_by_name(net, buf))
1069 /* It is possible to run out of possible slots
1070 * when the name is long and there isn't enough space left
1071 * for the digits, or if all bits are used.
1077 * dev_alloc_name - allocate a name for a device
1079 * @name: name format string
1081 * Passed a format string - eg "lt%d" it will try and find a suitable
1082 * id. It scans list of devices to build up a free map, then chooses
1083 * the first empty slot. The caller must hold the dev_base or rtnl lock
1084 * while allocating the name and adding the device in order to avoid
1086 * Limited to bits_per_byte * page size devices (ie 32K on most platforms).
1087 * Returns the number of the unit assigned or a negative errno code.
1090 int dev_alloc_name(struct net_device *dev, const char *name)
1096 BUG_ON(!dev_net(dev));
1098 ret = __dev_alloc_name(net, name, buf);
1100 strlcpy(dev->name, buf, IFNAMSIZ);
1103 EXPORT_SYMBOL(dev_alloc_name);
1105 static int dev_alloc_name_ns(struct net *net,
1106 struct net_device *dev,
1112 ret = __dev_alloc_name(net, name, buf);
1114 strlcpy(dev->name, buf, IFNAMSIZ);
1118 static int dev_get_valid_name(struct net *net,
1119 struct net_device *dev,
1124 if (!dev_valid_name(name))
1127 if (strchr(name, '%'))
1128 return dev_alloc_name_ns(net, dev, name);
1129 else if (__dev_get_by_name(net, name))
1131 else if (dev->name != name)
1132 strlcpy(dev->name, name, IFNAMSIZ);
1138 * dev_change_name - change name of a device
1140 * @newname: name (or format string) must be at least IFNAMSIZ
1142 * Change name of a device, can pass format strings "eth%d".
1145 int dev_change_name(struct net_device *dev, const char *newname)
1147 unsigned char old_assign_type;
1148 char oldname[IFNAMSIZ];
1154 BUG_ON(!dev_net(dev));
1157 if (dev->flags & IFF_UP)
1160 write_seqcount_begin(&devnet_rename_seq);
1162 if (strncmp(newname, dev->name, IFNAMSIZ) == 0) {
1163 write_seqcount_end(&devnet_rename_seq);
1167 memcpy(oldname, dev->name, IFNAMSIZ);
1169 err = dev_get_valid_name(net, dev, newname);
1171 write_seqcount_end(&devnet_rename_seq);
1175 if (oldname[0] && !strchr(oldname, '%'))
1176 netdev_info(dev, "renamed from %s\n", oldname);
1178 old_assign_type = dev->name_assign_type;
1179 dev->name_assign_type = NET_NAME_RENAMED;
1182 ret = device_rename(&dev->dev, dev->name);
1184 memcpy(dev->name, oldname, IFNAMSIZ);
1185 dev->name_assign_type = old_assign_type;
1186 write_seqcount_end(&devnet_rename_seq);
1190 write_seqcount_end(&devnet_rename_seq);
1192 netdev_adjacent_rename_links(dev, oldname);
1194 write_lock_bh(&dev_base_lock);
1195 hlist_del_rcu(&dev->name_hlist);
1196 write_unlock_bh(&dev_base_lock);
1200 write_lock_bh(&dev_base_lock);
1201 hlist_add_head_rcu(&dev->name_hlist, dev_name_hash(net, dev->name));
1202 write_unlock_bh(&dev_base_lock);
1204 ret = call_netdevice_notifiers(NETDEV_CHANGENAME, dev);
1205 ret = notifier_to_errno(ret);
1208 /* err >= 0 after dev_alloc_name() or stores the first errno */
1211 write_seqcount_begin(&devnet_rename_seq);
1212 memcpy(dev->name, oldname, IFNAMSIZ);
1213 memcpy(oldname, newname, IFNAMSIZ);
1214 dev->name_assign_type = old_assign_type;
1215 old_assign_type = NET_NAME_RENAMED;
1218 pr_err("%s: name change rollback failed: %d\n",
1227 * dev_set_alias - change ifalias of a device
1229 * @alias: name up to IFALIASZ
1230 * @len: limit of bytes to copy from info
1232 * Set ifalias for a device,
1234 int dev_set_alias(struct net_device *dev, const char *alias, size_t len)
1240 if (len >= IFALIASZ)
1244 kfree(dev->ifalias);
1245 dev->ifalias = NULL;
1249 new_ifalias = krealloc(dev->ifalias, len + 1, GFP_KERNEL);
1252 dev->ifalias = new_ifalias;
1254 strlcpy(dev->ifalias, alias, len+1);
1260 * netdev_features_change - device changes features
1261 * @dev: device to cause notification
1263 * Called to indicate a device has changed features.
1265 void netdev_features_change(struct net_device *dev)
1267 call_netdevice_notifiers(NETDEV_FEAT_CHANGE, dev);
1269 EXPORT_SYMBOL(netdev_features_change);
1272 * netdev_state_change - device changes state
1273 * @dev: device to cause notification
1275 * Called to indicate a device has changed state. This function calls
1276 * the notifier chains for netdev_chain and sends a NEWLINK message
1277 * to the routing socket.
1279 void netdev_state_change(struct net_device *dev)
1281 if (dev->flags & IFF_UP) {
1282 struct netdev_notifier_change_info change_info;
1284 change_info.flags_changed = 0;
1285 call_netdevice_notifiers_info(NETDEV_CHANGE, dev,
1287 rtmsg_ifinfo(RTM_NEWLINK, dev, 0, GFP_KERNEL);
1290 EXPORT_SYMBOL(netdev_state_change);
1293 * netdev_notify_peers - notify network peers about existence of @dev
1294 * @dev: network device
1296 * Generate traffic such that interested network peers are aware of
1297 * @dev, such as by generating a gratuitous ARP. This may be used when
1298 * a device wants to inform the rest of the network about some sort of
1299 * reconfiguration such as a failover event or virtual machine
1302 void netdev_notify_peers(struct net_device *dev)
1305 call_netdevice_notifiers(NETDEV_NOTIFY_PEERS, dev);
1308 EXPORT_SYMBOL(netdev_notify_peers);
1310 static int __dev_open(struct net_device *dev)
1312 const struct net_device_ops *ops = dev->netdev_ops;
1317 if (!netif_device_present(dev))
1320 /* Block netpoll from trying to do any rx path servicing.
1321 * If we don't do this there is a chance ndo_poll_controller
1322 * or ndo_poll may be running while we open the device
1324 netpoll_poll_disable(dev);
1326 ret = call_netdevice_notifiers(NETDEV_PRE_UP, dev);
1327 ret = notifier_to_errno(ret);
1331 set_bit(__LINK_STATE_START, &dev->state);
1333 if (ops->ndo_validate_addr)
1334 ret = ops->ndo_validate_addr(dev);
1336 if (!ret && ops->ndo_open)
1337 ret = ops->ndo_open(dev);
1339 netpoll_poll_enable(dev);
1342 clear_bit(__LINK_STATE_START, &dev->state);
1344 dev->flags |= IFF_UP;
1345 dev_set_rx_mode(dev);
1347 add_device_randomness(dev->dev_addr, dev->addr_len);
1354 * dev_open - prepare an interface for use.
1355 * @dev: device to open
1357 * Takes a device from down to up state. The device's private open
1358 * function is invoked and then the multicast lists are loaded. Finally
1359 * the device is moved into the up state and a %NETDEV_UP message is
1360 * sent to the netdev notifier chain.
1362 * Calling this function on an active interface is a nop. On a failure
1363 * a negative errno code is returned.
1365 int dev_open(struct net_device *dev)
1369 if (dev->flags & IFF_UP)
1372 ret = __dev_open(dev);
1376 rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP|IFF_RUNNING, GFP_KERNEL);
1377 call_netdevice_notifiers(NETDEV_UP, dev);
1381 EXPORT_SYMBOL(dev_open);
1383 static int __dev_close_many(struct list_head *head)
1385 struct net_device *dev;
1390 list_for_each_entry(dev, head, close_list) {
1391 /* Temporarily disable netpoll until the interface is down */
1392 netpoll_poll_disable(dev);
1394 call_netdevice_notifiers(NETDEV_GOING_DOWN, dev);
1396 clear_bit(__LINK_STATE_START, &dev->state);
1398 /* Synchronize to scheduled poll. We cannot touch poll list, it
1399 * can be even on different cpu. So just clear netif_running().
1401 * dev->stop() will invoke napi_disable() on all of it's
1402 * napi_struct instances on this device.
1404 smp_mb__after_atomic(); /* Commit netif_running(). */
1407 dev_deactivate_many(head);
1409 list_for_each_entry(dev, head, close_list) {
1410 const struct net_device_ops *ops = dev->netdev_ops;
1413 * Call the device specific close. This cannot fail.
1414 * Only if device is UP
1416 * We allow it to be called even after a DETACH hot-plug
1422 dev->flags &= ~IFF_UP;
1423 netpoll_poll_enable(dev);
1429 static int __dev_close(struct net_device *dev)
1434 list_add(&dev->close_list, &single);
1435 retval = __dev_close_many(&single);
1441 int dev_close_many(struct list_head *head, bool unlink)
1443 struct net_device *dev, *tmp;
1445 /* Remove the devices that don't need to be closed */
1446 list_for_each_entry_safe(dev, tmp, head, close_list)
1447 if (!(dev->flags & IFF_UP))
1448 list_del_init(&dev->close_list);
1450 __dev_close_many(head);
1452 list_for_each_entry_safe(dev, tmp, head, close_list) {
1453 rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP|IFF_RUNNING, GFP_KERNEL);
1454 call_netdevice_notifiers(NETDEV_DOWN, dev);
1456 list_del_init(&dev->close_list);
1461 EXPORT_SYMBOL(dev_close_many);
1464 * dev_close - shutdown an interface.
1465 * @dev: device to shutdown
1467 * This function moves an active device into down state. A
1468 * %NETDEV_GOING_DOWN is sent to the netdev notifier chain. The device
1469 * is then deactivated and finally a %NETDEV_DOWN is sent to the notifier
1472 int dev_close(struct net_device *dev)
1474 if (dev->flags & IFF_UP) {
1477 list_add(&dev->close_list, &single);
1478 dev_close_many(&single, true);
1483 EXPORT_SYMBOL(dev_close);
1487 * dev_disable_lro - disable Large Receive Offload on a device
1490 * Disable Large Receive Offload (LRO) on a net device. Must be
1491 * called under RTNL. This is needed if received packets may be
1492 * forwarded to another interface.
1494 void dev_disable_lro(struct net_device *dev)
1496 struct net_device *lower_dev;
1497 struct list_head *iter;
1499 dev->wanted_features &= ~NETIF_F_LRO;
1500 netdev_update_features(dev);
1502 if (unlikely(dev->features & NETIF_F_LRO))
1503 netdev_WARN(dev, "failed to disable LRO!\n");
1505 netdev_for_each_lower_dev(dev, lower_dev, iter)
1506 dev_disable_lro(lower_dev);
1508 EXPORT_SYMBOL(dev_disable_lro);
1510 static int call_netdevice_notifier(struct notifier_block *nb, unsigned long val,
1511 struct net_device *dev)
1513 struct netdev_notifier_info info;
1515 netdev_notifier_info_init(&info, dev);
1516 return nb->notifier_call(nb, val, &info);
1519 static int dev_boot_phase = 1;
1522 * register_netdevice_notifier - register a network notifier block
1525 * Register a notifier to be called when network device events occur.
1526 * The notifier passed is linked into the kernel structures and must
1527 * not be reused until it has been unregistered. A negative errno code
1528 * is returned on a failure.
1530 * When registered all registration and up events are replayed
1531 * to the new notifier to allow device to have a race free
1532 * view of the network device list.
1535 int register_netdevice_notifier(struct notifier_block *nb)
1537 struct net_device *dev;
1538 struct net_device *last;
1543 err = raw_notifier_chain_register(&netdev_chain, nb);
1549 for_each_netdev(net, dev) {
1550 err = call_netdevice_notifier(nb, NETDEV_REGISTER, dev);
1551 err = notifier_to_errno(err);
1555 if (!(dev->flags & IFF_UP))
1558 call_netdevice_notifier(nb, NETDEV_UP, dev);
1569 for_each_netdev(net, dev) {
1573 if (dev->flags & IFF_UP) {
1574 call_netdevice_notifier(nb, NETDEV_GOING_DOWN,
1576 call_netdevice_notifier(nb, NETDEV_DOWN, dev);
1578 call_netdevice_notifier(nb, NETDEV_UNREGISTER, dev);
1583 raw_notifier_chain_unregister(&netdev_chain, nb);
1586 EXPORT_SYMBOL(register_netdevice_notifier);
1589 * unregister_netdevice_notifier - unregister a network notifier block
1592 * Unregister a notifier previously registered by
1593 * register_netdevice_notifier(). The notifier is unlinked into the
1594 * kernel structures and may then be reused. A negative errno code
1595 * is returned on a failure.
1597 * After unregistering unregister and down device events are synthesized
1598 * for all devices on the device list to the removed notifier to remove
1599 * the need for special case cleanup code.
1602 int unregister_netdevice_notifier(struct notifier_block *nb)
1604 struct net_device *dev;
1609 err = raw_notifier_chain_unregister(&netdev_chain, nb);
1614 for_each_netdev(net, dev) {
1615 if (dev->flags & IFF_UP) {
1616 call_netdevice_notifier(nb, NETDEV_GOING_DOWN,
1618 call_netdevice_notifier(nb, NETDEV_DOWN, dev);
1620 call_netdevice_notifier(nb, NETDEV_UNREGISTER, dev);
1627 EXPORT_SYMBOL(unregister_netdevice_notifier);
1630 * call_netdevice_notifiers_info - call all network notifier blocks
1631 * @val: value passed unmodified to notifier function
1632 * @dev: net_device pointer passed unmodified to notifier function
1633 * @info: notifier information data
1635 * Call all network notifier blocks. Parameters and return value
1636 * are as for raw_notifier_call_chain().
1639 static int call_netdevice_notifiers_info(unsigned long val,
1640 struct net_device *dev,
1641 struct netdev_notifier_info *info)
1644 netdev_notifier_info_init(info, dev);
1645 return raw_notifier_call_chain(&netdev_chain, val, info);
1649 * call_netdevice_notifiers - call all network notifier blocks
1650 * @val: value passed unmodified to notifier function
1651 * @dev: net_device pointer passed unmodified to notifier function
1653 * Call all network notifier blocks. Parameters and return value
1654 * are as for raw_notifier_call_chain().
1657 int call_netdevice_notifiers(unsigned long val, struct net_device *dev)
1659 struct netdev_notifier_info info;
1661 return call_netdevice_notifiers_info(val, dev, &info);
1663 EXPORT_SYMBOL(call_netdevice_notifiers);
1665 #ifdef CONFIG_NET_INGRESS
1666 static struct static_key ingress_needed __read_mostly;
1668 void net_inc_ingress_queue(void)
1670 static_key_slow_inc(&ingress_needed);
1672 EXPORT_SYMBOL_GPL(net_inc_ingress_queue);
1674 void net_dec_ingress_queue(void)
1676 static_key_slow_dec(&ingress_needed);
1678 EXPORT_SYMBOL_GPL(net_dec_ingress_queue);
1681 #ifdef CONFIG_NET_EGRESS
1682 static struct static_key egress_needed __read_mostly;
1684 void net_inc_egress_queue(void)
1686 static_key_slow_inc(&egress_needed);
1688 EXPORT_SYMBOL_GPL(net_inc_egress_queue);
1690 void net_dec_egress_queue(void)
1692 static_key_slow_dec(&egress_needed);
1694 EXPORT_SYMBOL_GPL(net_dec_egress_queue);
1697 static struct static_key netstamp_needed __read_mostly;
1698 #ifdef HAVE_JUMP_LABEL
1699 /* We are not allowed to call static_key_slow_dec() from irq context
1700 * If net_disable_timestamp() is called from irq context, defer the
1701 * static_key_slow_dec() calls.
1703 static atomic_t netstamp_needed_deferred;
1706 void net_enable_timestamp(void)
1708 #ifdef HAVE_JUMP_LABEL
1709 int deferred = atomic_xchg(&netstamp_needed_deferred, 0);
1713 static_key_slow_dec(&netstamp_needed);
1717 static_key_slow_inc(&netstamp_needed);
1719 EXPORT_SYMBOL(net_enable_timestamp);
1721 void net_disable_timestamp(void)
1723 #ifdef HAVE_JUMP_LABEL
1724 if (in_interrupt()) {
1725 atomic_inc(&netstamp_needed_deferred);
1729 static_key_slow_dec(&netstamp_needed);
1731 EXPORT_SYMBOL(net_disable_timestamp);
1733 static inline void net_timestamp_set(struct sk_buff *skb)
1735 skb->tstamp.tv64 = 0;
1736 if (static_key_false(&netstamp_needed))
1737 __net_timestamp(skb);
1740 #define net_timestamp_check(COND, SKB) \
1741 if (static_key_false(&netstamp_needed)) { \
1742 if ((COND) && !(SKB)->tstamp.tv64) \
1743 __net_timestamp(SKB); \
1746 bool is_skb_forwardable(const struct net_device *dev, const struct sk_buff *skb)
1750 if (!(dev->flags & IFF_UP))
1753 len = dev->mtu + dev->hard_header_len + VLAN_HLEN;
1754 if (skb->len <= len)
1757 /* if TSO is enabled, we don't care about the length as the packet
1758 * could be forwarded without being segmented before
1760 if (skb_is_gso(skb))
1765 EXPORT_SYMBOL_GPL(is_skb_forwardable);
1767 int __dev_forward_skb(struct net_device *dev, struct sk_buff *skb)
1769 if (skb_orphan_frags(skb, GFP_ATOMIC) ||
1770 unlikely(!is_skb_forwardable(dev, skb))) {
1771 atomic_long_inc(&dev->rx_dropped);
1776 skb_scrub_packet(skb, true);
1778 skb->protocol = eth_type_trans(skb, dev);
1779 skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN);
1783 EXPORT_SYMBOL_GPL(__dev_forward_skb);
1786 * dev_forward_skb - loopback an skb to another netif
1788 * @dev: destination network device
1789 * @skb: buffer to forward
1792 * NET_RX_SUCCESS (no congestion)
1793 * NET_RX_DROP (packet was dropped, but freed)
1795 * dev_forward_skb can be used for injecting an skb from the
1796 * start_xmit function of one device into the receive queue
1797 * of another device.
1799 * The receiving device may be in another namespace, so
1800 * we have to clear all information in the skb that could
1801 * impact namespace isolation.
1803 int dev_forward_skb(struct net_device *dev, struct sk_buff *skb)
1805 return __dev_forward_skb(dev, skb) ?: netif_rx_internal(skb);
1807 EXPORT_SYMBOL_GPL(dev_forward_skb);
1809 static inline int deliver_skb(struct sk_buff *skb,
1810 struct packet_type *pt_prev,
1811 struct net_device *orig_dev)
1813 if (unlikely(skb_orphan_frags(skb, GFP_ATOMIC)))
1815 atomic_inc(&skb->users);
1816 return pt_prev->func(skb, skb->dev, pt_prev, orig_dev);
1819 static inline void deliver_ptype_list_skb(struct sk_buff *skb,
1820 struct packet_type **pt,
1821 struct net_device *orig_dev,
1823 struct list_head *ptype_list)
1825 struct packet_type *ptype, *pt_prev = *pt;
1827 list_for_each_entry_rcu(ptype, ptype_list, list) {
1828 if (ptype->type != type)
1831 deliver_skb(skb, pt_prev, orig_dev);
1837 static inline bool skb_loop_sk(struct packet_type *ptype, struct sk_buff *skb)
1839 if (!ptype->af_packet_priv || !skb->sk)
1842 if (ptype->id_match)
1843 return ptype->id_match(ptype, skb->sk);
1844 else if ((struct sock *)ptype->af_packet_priv == skb->sk)
1851 * Support routine. Sends outgoing frames to any network
1852 * taps currently in use.
1855 void dev_queue_xmit_nit(struct sk_buff *skb, struct net_device *dev)
1857 struct packet_type *ptype;
1858 struct sk_buff *skb2 = NULL;
1859 struct packet_type *pt_prev = NULL;
1860 struct list_head *ptype_list = &ptype_all;
1864 list_for_each_entry_rcu(ptype, ptype_list, list) {
1865 /* Never send packets back to the socket
1866 * they originated from - MvS (miquels@drinkel.ow.org)
1868 if (skb_loop_sk(ptype, skb))
1872 deliver_skb(skb2, pt_prev, skb->dev);
1877 /* need to clone skb, done only once */
1878 skb2 = skb_clone(skb, GFP_ATOMIC);
1882 net_timestamp_set(skb2);
1884 /* skb->nh should be correctly
1885 * set by sender, so that the second statement is
1886 * just protection against buggy protocols.
1888 skb_reset_mac_header(skb2);
1890 if (skb_network_header(skb2) < skb2->data ||
1891 skb_network_header(skb2) > skb_tail_pointer(skb2)) {
1892 net_crit_ratelimited("protocol %04x is buggy, dev %s\n",
1893 ntohs(skb2->protocol),
1895 skb_reset_network_header(skb2);
1898 skb2->transport_header = skb2->network_header;
1899 skb2->pkt_type = PACKET_OUTGOING;
1903 if (ptype_list == &ptype_all) {
1904 ptype_list = &dev->ptype_all;
1909 pt_prev->func(skb2, skb->dev, pt_prev, skb->dev);
1912 EXPORT_SYMBOL_GPL(dev_queue_xmit_nit);
1915 * netif_setup_tc - Handle tc mappings on real_num_tx_queues change
1916 * @dev: Network device
1917 * @txq: number of queues available
1919 * If real_num_tx_queues is changed the tc mappings may no longer be
1920 * valid. To resolve this verify the tc mapping remains valid and if
1921 * not NULL the mapping. With no priorities mapping to this
1922 * offset/count pair it will no longer be used. In the worst case TC0
1923 * is invalid nothing can be done so disable priority mappings. If is
1924 * expected that drivers will fix this mapping if they can before
1925 * calling netif_set_real_num_tx_queues.
1927 static void netif_setup_tc(struct net_device *dev, unsigned int txq)
1930 struct netdev_tc_txq *tc = &dev->tc_to_txq[0];
1932 /* If TC0 is invalidated disable TC mapping */
1933 if (tc->offset + tc->count > txq) {
1934 pr_warn("Number of in use tx queues changed invalidating tc mappings. Priority traffic classification disabled!\n");
1939 /* Invalidated prio to tc mappings set to TC0 */
1940 for (i = 1; i < TC_BITMASK + 1; i++) {
1941 int q = netdev_get_prio_tc_map(dev, i);
1943 tc = &dev->tc_to_txq[q];
1944 if (tc->offset + tc->count > txq) {
1945 pr_warn("Number of in use tx queues changed. Priority %i to tc mapping %i is no longer valid. Setting map to 0\n",
1947 netdev_set_prio_tc_map(dev, i, 0);
1953 static DEFINE_MUTEX(xps_map_mutex);
1954 #define xmap_dereference(P) \
1955 rcu_dereference_protected((P), lockdep_is_held(&xps_map_mutex))
1957 static struct xps_map *remove_xps_queue(struct xps_dev_maps *dev_maps,
1960 struct xps_map *map = NULL;
1964 map = xmap_dereference(dev_maps->cpu_map[cpu]);
1966 for (pos = 0; map && pos < map->len; pos++) {
1967 if (map->queues[pos] == index) {
1969 map->queues[pos] = map->queues[--map->len];
1971 RCU_INIT_POINTER(dev_maps->cpu_map[cpu], NULL);
1972 kfree_rcu(map, rcu);
1982 static void netif_reset_xps_queues_gt(struct net_device *dev, u16 index)
1984 struct xps_dev_maps *dev_maps;
1986 bool active = false;
1988 mutex_lock(&xps_map_mutex);
1989 dev_maps = xmap_dereference(dev->xps_maps);
1994 for_each_possible_cpu(cpu) {
1995 for (i = index; i < dev->num_tx_queues; i++) {
1996 if (!remove_xps_queue(dev_maps, cpu, i))
1999 if (i == dev->num_tx_queues)
2004 RCU_INIT_POINTER(dev->xps_maps, NULL);
2005 kfree_rcu(dev_maps, rcu);
2008 for (i = index; i < dev->num_tx_queues; i++)
2009 netdev_queue_numa_node_write(netdev_get_tx_queue(dev, i),
2013 mutex_unlock(&xps_map_mutex);
2016 static struct xps_map *expand_xps_map(struct xps_map *map,
2019 struct xps_map *new_map;
2020 int alloc_len = XPS_MIN_MAP_ALLOC;
2023 for (pos = 0; map && pos < map->len; pos++) {
2024 if (map->queues[pos] != index)
2029 /* Need to add queue to this CPU's existing map */
2031 if (pos < map->alloc_len)
2034 alloc_len = map->alloc_len * 2;
2037 /* Need to allocate new map to store queue on this CPU's map */
2038 new_map = kzalloc_node(XPS_MAP_SIZE(alloc_len), GFP_KERNEL,
2043 for (i = 0; i < pos; i++)
2044 new_map->queues[i] = map->queues[i];
2045 new_map->alloc_len = alloc_len;
2051 int netif_set_xps_queue(struct net_device *dev, const struct cpumask *mask,
2054 struct xps_dev_maps *dev_maps, *new_dev_maps = NULL;
2055 struct xps_map *map, *new_map;
2056 int maps_sz = max_t(unsigned int, XPS_DEV_MAPS_SIZE, L1_CACHE_BYTES);
2057 int cpu, numa_node_id = -2;
2058 bool active = false;
2060 mutex_lock(&xps_map_mutex);
2062 dev_maps = xmap_dereference(dev->xps_maps);
2064 /* allocate memory for queue storage */
2065 for_each_online_cpu(cpu) {
2066 if (!cpumask_test_cpu(cpu, mask))
2070 new_dev_maps = kzalloc(maps_sz, GFP_KERNEL);
2071 if (!new_dev_maps) {
2072 mutex_unlock(&xps_map_mutex);
2076 map = dev_maps ? xmap_dereference(dev_maps->cpu_map[cpu]) :
2079 map = expand_xps_map(map, cpu, index);
2083 RCU_INIT_POINTER(new_dev_maps->cpu_map[cpu], map);
2087 goto out_no_new_maps;
2089 for_each_possible_cpu(cpu) {
2090 if (cpumask_test_cpu(cpu, mask) && cpu_online(cpu)) {
2091 /* add queue to CPU maps */
2094 map = xmap_dereference(new_dev_maps->cpu_map[cpu]);
2095 while ((pos < map->len) && (map->queues[pos] != index))
2098 if (pos == map->len)
2099 map->queues[map->len++] = index;
2101 if (numa_node_id == -2)
2102 numa_node_id = cpu_to_node(cpu);
2103 else if (numa_node_id != cpu_to_node(cpu))
2106 } else if (dev_maps) {
2107 /* fill in the new device map from the old device map */
2108 map = xmap_dereference(dev_maps->cpu_map[cpu]);
2109 RCU_INIT_POINTER(new_dev_maps->cpu_map[cpu], map);
2114 rcu_assign_pointer(dev->xps_maps, new_dev_maps);
2116 /* Cleanup old maps */
2118 for_each_possible_cpu(cpu) {
2119 new_map = xmap_dereference(new_dev_maps->cpu_map[cpu]);
2120 map = xmap_dereference(dev_maps->cpu_map[cpu]);
2121 if (map && map != new_map)
2122 kfree_rcu(map, rcu);
2125 kfree_rcu(dev_maps, rcu);
2128 dev_maps = new_dev_maps;
2132 /* update Tx queue numa node */
2133 netdev_queue_numa_node_write(netdev_get_tx_queue(dev, index),
2134 (numa_node_id >= 0) ? numa_node_id :
2140 /* removes queue from unused CPUs */
2141 for_each_possible_cpu(cpu) {
2142 if (cpumask_test_cpu(cpu, mask) && cpu_online(cpu))
2145 if (remove_xps_queue(dev_maps, cpu, index))
2149 /* free map if not active */
2151 RCU_INIT_POINTER(dev->xps_maps, NULL);
2152 kfree_rcu(dev_maps, rcu);
2156 mutex_unlock(&xps_map_mutex);
2160 /* remove any maps that we added */
2161 for_each_possible_cpu(cpu) {
2162 new_map = xmap_dereference(new_dev_maps->cpu_map[cpu]);
2163 map = dev_maps ? xmap_dereference(dev_maps->cpu_map[cpu]) :
2165 if (new_map && new_map != map)
2169 mutex_unlock(&xps_map_mutex);
2171 kfree(new_dev_maps);
2174 EXPORT_SYMBOL(netif_set_xps_queue);
2178 * Routine to help set real_num_tx_queues. To avoid skbs mapped to queues
2179 * greater then real_num_tx_queues stale skbs on the qdisc must be flushed.
2181 int netif_set_real_num_tx_queues(struct net_device *dev, unsigned int txq)
2185 if (txq < 1 || txq > dev->num_tx_queues)
2188 if (dev->reg_state == NETREG_REGISTERED ||
2189 dev->reg_state == NETREG_UNREGISTERING) {
2192 rc = netdev_queue_update_kobjects(dev, dev->real_num_tx_queues,
2198 netif_setup_tc(dev, txq);
2200 if (txq < dev->real_num_tx_queues) {
2201 qdisc_reset_all_tx_gt(dev, txq);
2203 netif_reset_xps_queues_gt(dev, txq);
2208 dev->real_num_tx_queues = txq;
2211 EXPORT_SYMBOL(netif_set_real_num_tx_queues);
2215 * netif_set_real_num_rx_queues - set actual number of RX queues used
2216 * @dev: Network device
2217 * @rxq: Actual number of RX queues
2219 * This must be called either with the rtnl_lock held or before
2220 * registration of the net device. Returns 0 on success, or a
2221 * negative error code. If called before registration, it always
2224 int netif_set_real_num_rx_queues(struct net_device *dev, unsigned int rxq)
2228 if (rxq < 1 || rxq > dev->num_rx_queues)
2231 if (dev->reg_state == NETREG_REGISTERED) {
2234 rc = net_rx_queue_update_kobjects(dev, dev->real_num_rx_queues,
2240 dev->real_num_rx_queues = rxq;
2243 EXPORT_SYMBOL(netif_set_real_num_rx_queues);
2247 * netif_get_num_default_rss_queues - default number of RSS queues
2249 * This routine should set an upper limit on the number of RSS queues
2250 * used by default by multiqueue devices.
2252 int netif_get_num_default_rss_queues(void)
2254 return is_kdump_kernel() ?
2255 1 : min_t(int, DEFAULT_MAX_NUM_RSS_QUEUES, num_online_cpus());
2257 EXPORT_SYMBOL(netif_get_num_default_rss_queues);
2259 static void __netif_reschedule(struct Qdisc *q)
2261 struct softnet_data *sd;
2262 unsigned long flags;
2264 local_irq_save(flags);
2265 sd = this_cpu_ptr(&softnet_data);
2266 q->next_sched = NULL;
2267 *sd->output_queue_tailp = q;
2268 sd->output_queue_tailp = &q->next_sched;
2269 raise_softirq_irqoff(NET_TX_SOFTIRQ);
2270 local_irq_restore(flags);
2273 void __netif_schedule(struct Qdisc *q)
2275 if (!test_and_set_bit(__QDISC_STATE_SCHED, &q->state))
2276 __netif_reschedule(q);
2278 EXPORT_SYMBOL(__netif_schedule);
2280 struct dev_kfree_skb_cb {
2281 enum skb_free_reason reason;
2284 static struct dev_kfree_skb_cb *get_kfree_skb_cb(const struct sk_buff *skb)
2286 return (struct dev_kfree_skb_cb *)skb->cb;
2289 void netif_schedule_queue(struct netdev_queue *txq)
2292 if (!(txq->state & QUEUE_STATE_ANY_XOFF)) {
2293 struct Qdisc *q = rcu_dereference(txq->qdisc);
2295 __netif_schedule(q);
2299 EXPORT_SYMBOL(netif_schedule_queue);
2302 * netif_wake_subqueue - allow sending packets on subqueue
2303 * @dev: network device
2304 * @queue_index: sub queue index
2306 * Resume individual transmit queue of a device with multiple transmit queues.
2308 void netif_wake_subqueue(struct net_device *dev, u16 queue_index)
2310 struct netdev_queue *txq = netdev_get_tx_queue(dev, queue_index);
2312 if (test_and_clear_bit(__QUEUE_STATE_DRV_XOFF, &txq->state)) {
2316 q = rcu_dereference(txq->qdisc);
2317 __netif_schedule(q);
2321 EXPORT_SYMBOL(netif_wake_subqueue);
2323 void netif_tx_wake_queue(struct netdev_queue *dev_queue)
2325 if (test_and_clear_bit(__QUEUE_STATE_DRV_XOFF, &dev_queue->state)) {
2329 q = rcu_dereference(dev_queue->qdisc);
2330 __netif_schedule(q);
2334 EXPORT_SYMBOL(netif_tx_wake_queue);
2336 void __dev_kfree_skb_irq(struct sk_buff *skb, enum skb_free_reason reason)
2338 unsigned long flags;
2340 if (likely(atomic_read(&skb->users) == 1)) {
2342 atomic_set(&skb->users, 0);
2343 } else if (likely(!atomic_dec_and_test(&skb->users))) {
2346 get_kfree_skb_cb(skb)->reason = reason;
2347 local_irq_save(flags);
2348 skb->next = __this_cpu_read(softnet_data.completion_queue);
2349 __this_cpu_write(softnet_data.completion_queue, skb);
2350 raise_softirq_irqoff(NET_TX_SOFTIRQ);
2351 local_irq_restore(flags);
2353 EXPORT_SYMBOL(__dev_kfree_skb_irq);
2355 void __dev_kfree_skb_any(struct sk_buff *skb, enum skb_free_reason reason)
2357 if (in_irq() || irqs_disabled())
2358 __dev_kfree_skb_irq(skb, reason);
2362 EXPORT_SYMBOL(__dev_kfree_skb_any);
2366 * netif_device_detach - mark device as removed
2367 * @dev: network device
2369 * Mark device as removed from system and therefore no longer available.
2371 void netif_device_detach(struct net_device *dev)
2373 if (test_and_clear_bit(__LINK_STATE_PRESENT, &dev->state) &&
2374 netif_running(dev)) {
2375 netif_tx_stop_all_queues(dev);
2378 EXPORT_SYMBOL(netif_device_detach);
2381 * netif_device_attach - mark device as attached
2382 * @dev: network device
2384 * Mark device as attached from system and restart if needed.
2386 void netif_device_attach(struct net_device *dev)
2388 if (!test_and_set_bit(__LINK_STATE_PRESENT, &dev->state) &&
2389 netif_running(dev)) {
2390 netif_tx_wake_all_queues(dev);
2391 __netdev_watchdog_up(dev);
2394 EXPORT_SYMBOL(netif_device_attach);
2397 * Returns a Tx hash based on the given packet descriptor a Tx queues' number
2398 * to be used as a distribution range.
2400 u16 __skb_tx_hash(const struct net_device *dev, struct sk_buff *skb,
2401 unsigned int num_tx_queues)
2405 u16 qcount = num_tx_queues;
2407 if (skb_rx_queue_recorded(skb)) {
2408 hash = skb_get_rx_queue(skb);
2409 while (unlikely(hash >= num_tx_queues))
2410 hash -= num_tx_queues;
2415 u8 tc = netdev_get_prio_tc_map(dev, skb->priority);
2416 qoffset = dev->tc_to_txq[tc].offset;
2417 qcount = dev->tc_to_txq[tc].count;
2420 return (u16) reciprocal_scale(skb_get_hash(skb), qcount) + qoffset;
2422 EXPORT_SYMBOL(__skb_tx_hash);
2424 static void skb_warn_bad_offload(const struct sk_buff *skb)
2426 static const netdev_features_t null_features;
2427 struct net_device *dev = skb->dev;
2428 const char *name = "";
2430 if (!net_ratelimit())
2434 if (dev->dev.parent)
2435 name = dev_driver_string(dev->dev.parent);
2437 name = netdev_name(dev);
2439 WARN(1, "%s: caps=(%pNF, %pNF) len=%d data_len=%d gso_size=%d "
2440 "gso_type=%d ip_summed=%d\n",
2441 name, dev ? &dev->features : &null_features,
2442 skb->sk ? &skb->sk->sk_route_caps : &null_features,
2443 skb->len, skb->data_len, skb_shinfo(skb)->gso_size,
2444 skb_shinfo(skb)->gso_type, skb->ip_summed);
2448 * Invalidate hardware checksum when packet is to be mangled, and
2449 * complete checksum manually on outgoing path.
2451 int skb_checksum_help(struct sk_buff *skb)
2454 int ret = 0, offset;
2456 if (skb->ip_summed == CHECKSUM_COMPLETE)
2457 goto out_set_summed;
2459 if (unlikely(skb_shinfo(skb)->gso_size)) {
2460 skb_warn_bad_offload(skb);
2464 /* Before computing a checksum, we should make sure no frag could
2465 * be modified by an external entity : checksum could be wrong.
2467 if (skb_has_shared_frag(skb)) {
2468 ret = __skb_linearize(skb);
2473 offset = skb_checksum_start_offset(skb);
2474 BUG_ON(offset >= skb_headlen(skb));
2475 csum = skb_checksum(skb, offset, skb->len - offset, 0);
2477 offset += skb->csum_offset;
2478 BUG_ON(offset + sizeof(__sum16) > skb_headlen(skb));
2480 if (skb_cloned(skb) &&
2481 !skb_clone_writable(skb, offset + sizeof(__sum16))) {
2482 ret = pskb_expand_head(skb, 0, 0, GFP_ATOMIC);
2487 *(__sum16 *)(skb->data + offset) = csum_fold(csum);
2489 skb->ip_summed = CHECKSUM_NONE;
2493 EXPORT_SYMBOL(skb_checksum_help);
2495 /* skb_csum_offload_check - Driver helper function to determine if a device
2496 * with limited checksum offload capabilities is able to offload the checksum
2497 * for a given packet.
2500 * skb - sk_buff for the packet in question
2501 * spec - contains the description of what device can offload
2502 * csum_encapped - returns true if the checksum being offloaded is
2503 * encpasulated. That is it is checksum for the transport header
2504 * in the inner headers.
2505 * checksum_help - when set indicates that helper function should
2506 * call skb_checksum_help if offload checks fail
2509 * true: Packet has passed the checksum checks and should be offloadable to
2510 * the device (a driver may still need to check for additional
2511 * restrictions of its device)
2512 * false: Checksum is not offloadable. If checksum_help was set then
2513 * skb_checksum_help was called to resolve checksum for non-GSO
2514 * packets and when IP protocol is not SCTP
2516 bool __skb_csum_offload_chk(struct sk_buff *skb,
2517 const struct skb_csum_offl_spec *spec,
2518 bool *csum_encapped,
2522 struct ipv6hdr *ipv6;
2527 if (skb->protocol == htons(ETH_P_8021Q) ||
2528 skb->protocol == htons(ETH_P_8021AD)) {
2529 if (!spec->vlan_okay)
2533 /* We check whether the checksum refers to a transport layer checksum in
2534 * the outermost header or an encapsulated transport layer checksum that
2535 * corresponds to the inner headers of the skb. If the checksum is for
2536 * something else in the packet we need help.
2538 if (skb_checksum_start_offset(skb) == skb_transport_offset(skb)) {
2539 /* Non-encapsulated checksum */
2540 protocol = eproto_to_ipproto(vlan_get_protocol(skb));
2541 nhdr = skb_network_header(skb);
2542 *csum_encapped = false;
2543 if (spec->no_not_encapped)
2545 } else if (skb->encapsulation && spec->encap_okay &&
2546 skb_checksum_start_offset(skb) ==
2547 skb_inner_transport_offset(skb)) {
2548 /* Encapsulated checksum */
2549 *csum_encapped = true;
2550 switch (skb->inner_protocol_type) {
2551 case ENCAP_TYPE_ETHER:
2552 protocol = eproto_to_ipproto(skb->inner_protocol);
2554 case ENCAP_TYPE_IPPROTO:
2555 protocol = skb->inner_protocol;
2558 nhdr = skb_inner_network_header(skb);
2565 if (!spec->ipv4_okay)
2568 ip_proto = iph->protocol;
2569 if (iph->ihl != 5 && !spec->ip_options_okay)
2573 if (!spec->ipv6_okay)
2575 if (spec->no_encapped_ipv6 && *csum_encapped)
2578 nhdr += sizeof(*ipv6);
2579 ip_proto = ipv6->nexthdr;
2588 if (!spec->tcp_okay ||
2589 skb->csum_offset != offsetof(struct tcphdr, check))
2593 if (!spec->udp_okay ||
2594 skb->csum_offset != offsetof(struct udphdr, check))
2598 if (!spec->sctp_okay ||
2599 skb->csum_offset != offsetof(struct sctphdr, checksum))
2603 case NEXTHDR_ROUTING:
2604 case NEXTHDR_DEST: {
2607 if (protocol != IPPROTO_IPV6 || !spec->ext_hdrs_okay)
2610 ip_proto = opthdr[0];
2611 nhdr += (opthdr[1] + 1) << 3;
2613 goto ip_proto_again;
2619 /* Passed the tests for offloading checksum */
2623 if (csum_help && !skb_shinfo(skb)->gso_size)
2624 skb_checksum_help(skb);
2628 EXPORT_SYMBOL(__skb_csum_offload_chk);
2630 __be16 skb_network_protocol(struct sk_buff *skb, int *depth)
2632 __be16 type = skb->protocol;
2634 /* Tunnel gso handlers can set protocol to ethernet. */
2635 if (type == htons(ETH_P_TEB)) {
2638 if (unlikely(!pskb_may_pull(skb, sizeof(struct ethhdr))))
2641 eth = (struct ethhdr *)skb_mac_header(skb);
2642 type = eth->h_proto;
2645 return __vlan_get_protocol(skb, type, depth);
2649 * skb_mac_gso_segment - mac layer segmentation handler.
2650 * @skb: buffer to segment
2651 * @features: features for the output path (see dev->features)
2653 struct sk_buff *skb_mac_gso_segment(struct sk_buff *skb,
2654 netdev_features_t features)
2656 struct sk_buff *segs = ERR_PTR(-EPROTONOSUPPORT);
2657 struct packet_offload *ptype;
2658 int vlan_depth = skb->mac_len;
2659 __be16 type = skb_network_protocol(skb, &vlan_depth);
2661 if (unlikely(!type))
2662 return ERR_PTR(-EINVAL);
2664 __skb_pull(skb, vlan_depth);
2667 list_for_each_entry_rcu(ptype, &offload_base, list) {
2668 if (ptype->type == type && ptype->callbacks.gso_segment) {
2669 segs = ptype->callbacks.gso_segment(skb, features);
2675 __skb_push(skb, skb->data - skb_mac_header(skb));
2679 EXPORT_SYMBOL(skb_mac_gso_segment);
2682 /* openvswitch calls this on rx path, so we need a different check.
2684 static inline bool skb_needs_check(struct sk_buff *skb, bool tx_path)
2687 return skb->ip_summed != CHECKSUM_PARTIAL;
2689 return skb->ip_summed == CHECKSUM_NONE;
2693 * __skb_gso_segment - Perform segmentation on skb.
2694 * @skb: buffer to segment
2695 * @features: features for the output path (see dev->features)
2696 * @tx_path: whether it is called in TX path
2698 * This function segments the given skb and returns a list of segments.
2700 * It may return NULL if the skb requires no segmentation. This is
2701 * only possible when GSO is used for verifying header integrity.
2703 * Segmentation preserves SKB_SGO_CB_OFFSET bytes of previous skb cb.
2705 struct sk_buff *__skb_gso_segment(struct sk_buff *skb,
2706 netdev_features_t features, bool tx_path)
2708 if (unlikely(skb_needs_check(skb, tx_path))) {
2711 skb_warn_bad_offload(skb);
2713 err = skb_cow_head(skb, 0);
2715 return ERR_PTR(err);
2718 /* Only report GSO partial support if it will enable us to
2719 * support segmentation on this frame without needing additional
2722 if (features & NETIF_F_GSO_PARTIAL) {
2723 netdev_features_t partial_features = NETIF_F_GSO_ROBUST;
2724 struct net_device *dev = skb->dev;
2726 partial_features |= dev->features & dev->gso_partial_features;
2727 if (!skb_gso_ok(skb, features | partial_features))
2728 features &= ~NETIF_F_GSO_PARTIAL;
2731 BUILD_BUG_ON(SKB_SGO_CB_OFFSET +
2732 sizeof(*SKB_GSO_CB(skb)) > sizeof(skb->cb));
2734 SKB_GSO_CB(skb)->mac_offset = skb_headroom(skb);
2735 SKB_GSO_CB(skb)->encap_level = 0;
2737 skb_reset_mac_header(skb);
2738 skb_reset_mac_len(skb);
2740 return skb_mac_gso_segment(skb, features);
2742 EXPORT_SYMBOL(__skb_gso_segment);
2744 /* Take action when hardware reception checksum errors are detected. */
2746 void netdev_rx_csum_fault(struct net_device *dev)
2748 if (net_ratelimit()) {
2749 pr_err("%s: hw csum failure\n", dev ? dev->name : "<unknown>");
2753 EXPORT_SYMBOL(netdev_rx_csum_fault);
2756 /* Actually, we should eliminate this check as soon as we know, that:
2757 * 1. IOMMU is present and allows to map all the memory.
2758 * 2. No high memory really exists on this machine.
2761 static int illegal_highdma(struct net_device *dev, struct sk_buff *skb)
2763 #ifdef CONFIG_HIGHMEM
2765 if (!(dev->features & NETIF_F_HIGHDMA)) {
2766 for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
2767 skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
2768 if (PageHighMem(skb_frag_page(frag)))
2773 if (PCI_DMA_BUS_IS_PHYS) {
2774 struct device *pdev = dev->dev.parent;
2778 for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
2779 skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
2780 dma_addr_t addr = page_to_phys(skb_frag_page(frag));
2781 if (!pdev->dma_mask || addr + PAGE_SIZE - 1 > *pdev->dma_mask)
2789 /* If MPLS offload request, verify we are testing hardware MPLS features
2790 * instead of standard features for the netdev.
2792 #if IS_ENABLED(CONFIG_NET_MPLS_GSO)
2793 static netdev_features_t net_mpls_features(struct sk_buff *skb,
2794 netdev_features_t features,
2797 if (eth_p_mpls(type))
2798 features &= skb->dev->mpls_features;
2803 static netdev_features_t net_mpls_features(struct sk_buff *skb,
2804 netdev_features_t features,
2811 static netdev_features_t harmonize_features(struct sk_buff *skb,
2812 netdev_features_t features)
2817 type = skb_network_protocol(skb, &tmp);
2818 features = net_mpls_features(skb, features, type);
2820 if (skb->ip_summed != CHECKSUM_NONE &&
2821 !can_checksum_protocol(features, type)) {
2822 features &= ~(NETIF_F_CSUM_MASK | NETIF_F_GSO_MASK);
2823 } else if (illegal_highdma(skb->dev, skb)) {
2824 features &= ~NETIF_F_SG;
2830 netdev_features_t passthru_features_check(struct sk_buff *skb,
2831 struct net_device *dev,
2832 netdev_features_t features)
2836 EXPORT_SYMBOL(passthru_features_check);
2838 static netdev_features_t dflt_features_check(const struct sk_buff *skb,
2839 struct net_device *dev,
2840 netdev_features_t features)
2842 return vlan_features_check(skb, features);
2845 static netdev_features_t gso_features_check(const struct sk_buff *skb,
2846 struct net_device *dev,
2847 netdev_features_t features)
2849 u16 gso_segs = skb_shinfo(skb)->gso_segs;
2851 if (gso_segs > dev->gso_max_segs)
2852 return features & ~NETIF_F_GSO_MASK;
2854 /* Support for GSO partial features requires software
2855 * intervention before we can actually process the packets
2856 * so we need to strip support for any partial features now
2857 * and we can pull them back in after we have partially
2858 * segmented the frame.
2860 if (!(skb_shinfo(skb)->gso_type & SKB_GSO_PARTIAL))
2861 features &= ~dev->gso_partial_features;
2863 /* Make sure to clear the IPv4 ID mangling feature if the
2864 * IPv4 header has the potential to be fragmented.
2866 if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV4) {
2867 struct iphdr *iph = skb->encapsulation ?
2868 inner_ip_hdr(skb) : ip_hdr(skb);
2870 if (!(iph->frag_off & htons(IP_DF)))
2871 features &= ~NETIF_F_TSO_MANGLEID;
2877 netdev_features_t netif_skb_features(struct sk_buff *skb)
2879 struct net_device *dev = skb->dev;
2880 netdev_features_t features = dev->features;
2882 if (skb_is_gso(skb))
2883 features = gso_features_check(skb, dev, features);
2885 /* If encapsulation offload request, verify we are testing
2886 * hardware encapsulation features instead of standard
2887 * features for the netdev
2889 if (skb->encapsulation)
2890 features &= dev->hw_enc_features;
2892 if (skb_vlan_tagged(skb))
2893 features = netdev_intersect_features(features,
2894 dev->vlan_features |
2895 NETIF_F_HW_VLAN_CTAG_TX |
2896 NETIF_F_HW_VLAN_STAG_TX);
2898 if (dev->netdev_ops->ndo_features_check)
2899 features &= dev->netdev_ops->ndo_features_check(skb, dev,
2902 features &= dflt_features_check(skb, dev, features);
2904 return harmonize_features(skb, features);
2906 EXPORT_SYMBOL(netif_skb_features);
2908 static int xmit_one(struct sk_buff *skb, struct net_device *dev,
2909 struct netdev_queue *txq, bool more)
2914 if (!list_empty(&ptype_all) || !list_empty(&dev->ptype_all))
2915 dev_queue_xmit_nit(skb, dev);
2918 trace_net_dev_start_xmit(skb, dev);
2919 rc = netdev_start_xmit(skb, dev, txq, more);
2920 trace_net_dev_xmit(skb, rc, dev, len);
2925 struct sk_buff *dev_hard_start_xmit(struct sk_buff *first, struct net_device *dev,
2926 struct netdev_queue *txq, int *ret)
2928 struct sk_buff *skb = first;
2929 int rc = NETDEV_TX_OK;
2932 struct sk_buff *next = skb->next;
2935 rc = xmit_one(skb, dev, txq, next != NULL);
2936 if (unlikely(!dev_xmit_complete(rc))) {
2942 if (netif_xmit_stopped(txq) && skb) {
2943 rc = NETDEV_TX_BUSY;
2953 static struct sk_buff *validate_xmit_vlan(struct sk_buff *skb,
2954 netdev_features_t features)
2956 if (skb_vlan_tag_present(skb) &&
2957 !vlan_hw_offload_capable(features, skb->vlan_proto))
2958 skb = __vlan_hwaccel_push_inside(skb);
2962 static struct sk_buff *validate_xmit_skb(struct sk_buff *skb, struct net_device *dev)
2964 netdev_features_t features;
2966 features = netif_skb_features(skb);
2967 skb = validate_xmit_vlan(skb, features);
2971 if (netif_needs_gso(skb, features)) {
2972 struct sk_buff *segs;
2974 segs = skb_gso_segment(skb, features);
2982 if (skb_needs_linearize(skb, features) &&
2983 __skb_linearize(skb))
2986 /* If packet is not checksummed and device does not
2987 * support checksumming for this protocol, complete
2988 * checksumming here.
2990 if (skb->ip_summed == CHECKSUM_PARTIAL) {
2991 if (skb->encapsulation)
2992 skb_set_inner_transport_header(skb,
2993 skb_checksum_start_offset(skb));
2995 skb_set_transport_header(skb,
2996 skb_checksum_start_offset(skb));
2997 if (!(features & NETIF_F_CSUM_MASK) &&
2998 skb_checksum_help(skb))
3008 atomic_long_inc(&dev->tx_dropped);
3012 struct sk_buff *validate_xmit_skb_list(struct sk_buff *skb, struct net_device *dev)
3014 struct sk_buff *next, *head = NULL, *tail;
3016 for (; skb != NULL; skb = next) {
3020 /* in case skb wont be segmented, point to itself */
3023 skb = validate_xmit_skb(skb, dev);
3031 /* If skb was segmented, skb->prev points to
3032 * the last segment. If not, it still contains skb.
3039 static void qdisc_pkt_len_init(struct sk_buff *skb)
3041 const struct skb_shared_info *shinfo = skb_shinfo(skb);
3043 qdisc_skb_cb(skb)->pkt_len = skb->len;
3045 /* To get more precise estimation of bytes sent on wire,
3046 * we add to pkt_len the headers size of all segments
3048 if (shinfo->gso_size) {
3049 unsigned int hdr_len;
3050 u16 gso_segs = shinfo->gso_segs;
3052 /* mac layer + network layer */
3053 hdr_len = skb_transport_header(skb) - skb_mac_header(skb);
3055 /* + transport layer */
3056 if (likely(shinfo->gso_type & (SKB_GSO_TCPV4 | SKB_GSO_TCPV6)))
3057 hdr_len += tcp_hdrlen(skb);
3059 hdr_len += sizeof(struct udphdr);
3061 if (shinfo->gso_type & SKB_GSO_DODGY)
3062 gso_segs = DIV_ROUND_UP(skb->len - hdr_len,
3065 qdisc_skb_cb(skb)->pkt_len += (gso_segs - 1) * hdr_len;
3069 static inline int __dev_xmit_skb(struct sk_buff *skb, struct Qdisc *q,
3070 struct net_device *dev,
3071 struct netdev_queue *txq)
3073 spinlock_t *root_lock = qdisc_lock(q);
3074 struct sk_buff *to_free = NULL;
3078 qdisc_calculate_pkt_len(skb, q);
3080 * Heuristic to force contended enqueues to serialize on a
3081 * separate lock before trying to get qdisc main lock.
3082 * This permits qdisc->running owner to get the lock more
3083 * often and dequeue packets faster.
3085 contended = qdisc_is_running(q);
3086 if (unlikely(contended))
3087 spin_lock(&q->busylock);
3089 spin_lock(root_lock);
3090 if (unlikely(test_bit(__QDISC_STATE_DEACTIVATED, &q->state))) {
3091 __qdisc_drop(skb, &to_free);
3093 } else if ((q->flags & TCQ_F_CAN_BYPASS) && !qdisc_qlen(q) &&
3094 qdisc_run_begin(q)) {
3096 * This is a work-conserving queue; there are no old skbs
3097 * waiting to be sent out; and the qdisc is not running -
3098 * xmit the skb directly.
3101 qdisc_bstats_update(q, skb);
3103 if (sch_direct_xmit(skb, q, dev, txq, root_lock, true)) {
3104 if (unlikely(contended)) {
3105 spin_unlock(&q->busylock);
3112 rc = NET_XMIT_SUCCESS;
3114 rc = q->enqueue(skb, q, &to_free) & NET_XMIT_MASK;
3115 if (qdisc_run_begin(q)) {
3116 if (unlikely(contended)) {
3117 spin_unlock(&q->busylock);
3123 spin_unlock(root_lock);
3124 if (unlikely(to_free))
3125 kfree_skb_list(to_free);
3126 if (unlikely(contended))
3127 spin_unlock(&q->busylock);
3131 #if IS_ENABLED(CONFIG_CGROUP_NET_PRIO)
3132 static void skb_update_prio(struct sk_buff *skb)
3134 struct netprio_map *map = rcu_dereference_bh(skb->dev->priomap);
3136 if (!skb->priority && skb->sk && map) {
3137 unsigned int prioidx =
3138 sock_cgroup_prioidx(&skb->sk->sk_cgrp_data);
3140 if (prioidx < map->priomap_len)
3141 skb->priority = map->priomap[prioidx];
3145 #define skb_update_prio(skb)
3148 DEFINE_PER_CPU(int, xmit_recursion);
3149 EXPORT_SYMBOL(xmit_recursion);
3152 * dev_loopback_xmit - loop back @skb
3153 * @net: network namespace this loopback is happening in
3154 * @sk: sk needed to be a netfilter okfn
3155 * @skb: buffer to transmit
3157 int dev_loopback_xmit(struct net *net, struct sock *sk, struct sk_buff *skb)
3159 skb_reset_mac_header(skb);
3160 __skb_pull(skb, skb_network_offset(skb));
3161 skb->pkt_type = PACKET_LOOPBACK;
3162 skb->ip_summed = CHECKSUM_UNNECESSARY;
3163 WARN_ON(!skb_dst(skb));
3168 EXPORT_SYMBOL(dev_loopback_xmit);
3170 #ifdef CONFIG_NET_EGRESS
3171 static struct sk_buff *
3172 sch_handle_egress(struct sk_buff *skb, int *ret, struct net_device *dev)
3174 struct tcf_proto *cl = rcu_dereference_bh(dev->egress_cl_list);
3175 struct tcf_result cl_res;
3180 /* skb->tc_verd and qdisc_skb_cb(skb)->pkt_len were already set
3181 * earlier by the caller.
3183 qdisc_bstats_cpu_update(cl->q, skb);
3185 switch (tc_classify(skb, cl, &cl_res, false)) {
3187 case TC_ACT_RECLASSIFY:
3188 skb->tc_index = TC_H_MIN(cl_res.classid);
3191 qdisc_qstats_cpu_drop(cl->q);
3192 *ret = NET_XMIT_DROP;
3197 *ret = NET_XMIT_SUCCESS;
3200 case TC_ACT_REDIRECT:
3201 /* No need to push/pop skb's mac_header here on egress! */
3202 skb_do_redirect(skb);
3203 *ret = NET_XMIT_SUCCESS;
3211 #endif /* CONFIG_NET_EGRESS */
3213 static inline int get_xps_queue(struct net_device *dev, struct sk_buff *skb)
3216 struct xps_dev_maps *dev_maps;
3217 struct xps_map *map;
3218 int queue_index = -1;
3221 dev_maps = rcu_dereference(dev->xps_maps);
3223 map = rcu_dereference(
3224 dev_maps->cpu_map[skb->sender_cpu - 1]);
3227 queue_index = map->queues[0];
3229 queue_index = map->queues[reciprocal_scale(skb_get_hash(skb),
3231 if (unlikely(queue_index >= dev->real_num_tx_queues))
3243 static u16 __netdev_pick_tx(struct net_device *dev, struct sk_buff *skb)
3245 struct sock *sk = skb->sk;
3246 int queue_index = sk_tx_queue_get(sk);
3248 if (queue_index < 0 || skb->ooo_okay ||
3249 queue_index >= dev->real_num_tx_queues) {
3250 int new_index = get_xps_queue(dev, skb);
3252 new_index = skb_tx_hash(dev, skb);
3254 if (queue_index != new_index && sk &&
3256 rcu_access_pointer(sk->sk_dst_cache))
3257 sk_tx_queue_set(sk, new_index);
3259 queue_index = new_index;
3265 struct netdev_queue *netdev_pick_tx(struct net_device *dev,
3266 struct sk_buff *skb,
3269 int queue_index = 0;
3272 u32 sender_cpu = skb->sender_cpu - 1;
3274 if (sender_cpu >= (u32)NR_CPUS)
3275 skb->sender_cpu = raw_smp_processor_id() + 1;
3278 if (dev->real_num_tx_queues != 1) {
3279 const struct net_device_ops *ops = dev->netdev_ops;
3280 if (ops->ndo_select_queue)
3281 queue_index = ops->ndo_select_queue(dev, skb, accel_priv,
3284 queue_index = __netdev_pick_tx(dev, skb);
3287 queue_index = netdev_cap_txqueue(dev, queue_index);
3290 skb_set_queue_mapping(skb, queue_index);
3291 return netdev_get_tx_queue(dev, queue_index);
3295 * __dev_queue_xmit - transmit a buffer
3296 * @skb: buffer to transmit
3297 * @accel_priv: private data used for L2 forwarding offload
3299 * Queue a buffer for transmission to a network device. The caller must
3300 * have set the device and priority and built the buffer before calling
3301 * this function. The function can be called from an interrupt.
3303 * A negative errno code is returned on a failure. A success does not
3304 * guarantee the frame will be transmitted as it may be dropped due
3305 * to congestion or traffic shaping.
3307 * -----------------------------------------------------------------------------------
3308 * I notice this method can also return errors from the queue disciplines,
3309 * including NET_XMIT_DROP, which is a positive value. So, errors can also
3312 * Regardless of the return value, the skb is consumed, so it is currently
3313 * difficult to retry a send to this method. (You can bump the ref count
3314 * before sending to hold a reference for retry if you are careful.)
3316 * When calling this method, interrupts MUST be enabled. This is because
3317 * the BH enable code must have IRQs enabled so that it will not deadlock.
3320 static int __dev_queue_xmit(struct sk_buff *skb, void *accel_priv)
3322 struct net_device *dev = skb->dev;
3323 struct netdev_queue *txq;
3327 skb_reset_mac_header(skb);
3329 if (unlikely(skb_shinfo(skb)->tx_flags & SKBTX_SCHED_TSTAMP))
3330 __skb_tstamp_tx(skb, NULL, skb->sk, SCM_TSTAMP_SCHED);
3332 /* Disable soft irqs for various locks below. Also
3333 * stops preemption for RCU.
3337 skb_update_prio(skb);
3339 qdisc_pkt_len_init(skb);
3340 #ifdef CONFIG_NET_CLS_ACT
3341 skb->tc_verd = SET_TC_AT(skb->tc_verd, AT_EGRESS);
3342 # ifdef CONFIG_NET_EGRESS
3343 if (static_key_false(&egress_needed)) {
3344 skb = sch_handle_egress(skb, &rc, dev);
3350 /* If device/qdisc don't need skb->dst, release it right now while
3351 * its hot in this cpu cache.
3353 if (dev->priv_flags & IFF_XMIT_DST_RELEASE)
3358 txq = netdev_pick_tx(dev, skb, accel_priv);
3359 q = rcu_dereference_bh(txq->qdisc);
3361 trace_net_dev_queue(skb);
3363 rc = __dev_xmit_skb(skb, q, dev, txq);
3367 /* The device has no queue. Common case for software devices:
3368 loopback, all the sorts of tunnels...
3370 Really, it is unlikely that netif_tx_lock protection is necessary
3371 here. (f.e. loopback and IP tunnels are clean ignoring statistics
3373 However, it is possible, that they rely on protection
3376 Check this and shot the lock. It is not prone from deadlocks.
3377 Either shot noqueue qdisc, it is even simpler 8)
3379 if (dev->flags & IFF_UP) {
3380 int cpu = smp_processor_id(); /* ok because BHs are off */
3382 if (txq->xmit_lock_owner != cpu) {
3383 if (unlikely(__this_cpu_read(xmit_recursion) >
3384 XMIT_RECURSION_LIMIT))
3385 goto recursion_alert;
3387 skb = validate_xmit_skb(skb, dev);
3391 HARD_TX_LOCK(dev, txq, cpu);
3393 if (!netif_xmit_stopped(txq)) {
3394 __this_cpu_inc(xmit_recursion);
3395 skb = dev_hard_start_xmit(skb, dev, txq, &rc);
3396 __this_cpu_dec(xmit_recursion);
3397 if (dev_xmit_complete(rc)) {
3398 HARD_TX_UNLOCK(dev, txq);
3402 HARD_TX_UNLOCK(dev, txq);
3403 net_crit_ratelimited("Virtual device %s asks to queue packet!\n",
3406 /* Recursion is detected! It is possible,
3410 net_crit_ratelimited("Dead loop on virtual device %s, fix it urgently!\n",
3416 rcu_read_unlock_bh();
3418 atomic_long_inc(&dev->tx_dropped);
3419 kfree_skb_list(skb);
3422 rcu_read_unlock_bh();
3426 int dev_queue_xmit(struct sk_buff *skb)
3428 return __dev_queue_xmit(skb, NULL);
3430 EXPORT_SYMBOL(dev_queue_xmit);
3432 int dev_queue_xmit_accel(struct sk_buff *skb, void *accel_priv)
3434 return __dev_queue_xmit(skb, accel_priv);
3436 EXPORT_SYMBOL(dev_queue_xmit_accel);
3439 /*=======================================================================
3441 =======================================================================*/
3443 int netdev_max_backlog __read_mostly = 1000;
3444 EXPORT_SYMBOL(netdev_max_backlog);
3446 int netdev_tstamp_prequeue __read_mostly = 1;
3447 int netdev_budget __read_mostly = 300;
3448 int weight_p __read_mostly = 64; /* old backlog weight */
3450 /* Called with irq disabled */
3451 static inline void ____napi_schedule(struct softnet_data *sd,
3452 struct napi_struct *napi)
3454 list_add_tail(&napi->poll_list, &sd->poll_list);
3455 __raise_softirq_irqoff(NET_RX_SOFTIRQ);
3460 /* One global table that all flow-based protocols share. */
3461 struct rps_sock_flow_table __rcu *rps_sock_flow_table __read_mostly;
3462 EXPORT_SYMBOL(rps_sock_flow_table);
3463 u32 rps_cpu_mask __read_mostly;
3464 EXPORT_SYMBOL(rps_cpu_mask);
3466 struct static_key rps_needed __read_mostly;
3467 EXPORT_SYMBOL(rps_needed);
3469 static struct rps_dev_flow *
3470 set_rps_cpu(struct net_device *dev, struct sk_buff *skb,
3471 struct rps_dev_flow *rflow, u16 next_cpu)
3473 if (next_cpu < nr_cpu_ids) {
3474 #ifdef CONFIG_RFS_ACCEL
3475 struct netdev_rx_queue *rxqueue;
3476 struct rps_dev_flow_table *flow_table;
3477 struct rps_dev_flow *old_rflow;
3482 /* Should we steer this flow to a different hardware queue? */
3483 if (!skb_rx_queue_recorded(skb) || !dev->rx_cpu_rmap ||
3484 !(dev->features & NETIF_F_NTUPLE))
3486 rxq_index = cpu_rmap_lookup_index(dev->rx_cpu_rmap, next_cpu);
3487 if (rxq_index == skb_get_rx_queue(skb))
3490 rxqueue = dev->_rx + rxq_index;
3491 flow_table = rcu_dereference(rxqueue->rps_flow_table);
3494 flow_id = skb_get_hash(skb) & flow_table->mask;
3495 rc = dev->netdev_ops->ndo_rx_flow_steer(dev, skb,
3496 rxq_index, flow_id);
3500 rflow = &flow_table->flows[flow_id];
3502 if (old_rflow->filter == rflow->filter)
3503 old_rflow->filter = RPS_NO_FILTER;
3507 per_cpu(softnet_data, next_cpu).input_queue_head;
3510 rflow->cpu = next_cpu;
3515 * get_rps_cpu is called from netif_receive_skb and returns the target
3516 * CPU from the RPS map of the receiving queue for a given skb.
3517 * rcu_read_lock must be held on entry.
3519 static int get_rps_cpu(struct net_device *dev, struct sk_buff *skb,
3520 struct rps_dev_flow **rflowp)
3522 const struct rps_sock_flow_table *sock_flow_table;
3523 struct netdev_rx_queue *rxqueue = dev->_rx;
3524 struct rps_dev_flow_table *flow_table;
3525 struct rps_map *map;
3530 if (skb_rx_queue_recorded(skb)) {
3531 u16 index = skb_get_rx_queue(skb);
3533 if (unlikely(index >= dev->real_num_rx_queues)) {
3534 WARN_ONCE(dev->real_num_rx_queues > 1,
3535 "%s received packet on queue %u, but number "
3536 "of RX queues is %u\n",
3537 dev->name, index, dev->real_num_rx_queues);
3543 /* Avoid computing hash if RFS/RPS is not active for this rxqueue */
3545 flow_table = rcu_dereference(rxqueue->rps_flow_table);
3546 map = rcu_dereference(rxqueue->rps_map);
3547 if (!flow_table && !map)
3550 skb_reset_network_header(skb);
3551 hash = skb_get_hash(skb);
3555 sock_flow_table = rcu_dereference(rps_sock_flow_table);
3556 if (flow_table && sock_flow_table) {
3557 struct rps_dev_flow *rflow;
3561 /* First check into global flow table if there is a match */
3562 ident = sock_flow_table->ents[hash & sock_flow_table->mask];
3563 if ((ident ^ hash) & ~rps_cpu_mask)
3566 next_cpu = ident & rps_cpu_mask;
3568 /* OK, now we know there is a match,
3569 * we can look at the local (per receive queue) flow table
3571 rflow = &flow_table->flows[hash & flow_table->mask];
3575 * If the desired CPU (where last recvmsg was done) is
3576 * different from current CPU (one in the rx-queue flow
3577 * table entry), switch if one of the following holds:
3578 * - Current CPU is unset (>= nr_cpu_ids).
3579 * - Current CPU is offline.
3580 * - The current CPU's queue tail has advanced beyond the
3581 * last packet that was enqueued using this table entry.
3582 * This guarantees that all previous packets for the flow
3583 * have been dequeued, thus preserving in order delivery.
3585 if (unlikely(tcpu != next_cpu) &&
3586 (tcpu >= nr_cpu_ids || !cpu_online(tcpu) ||
3587 ((int)(per_cpu(softnet_data, tcpu).input_queue_head -
3588 rflow->last_qtail)) >= 0)) {
3590 rflow = set_rps_cpu(dev, skb, rflow, next_cpu);
3593 if (tcpu < nr_cpu_ids && cpu_online(tcpu)) {
3603 tcpu = map->cpus[reciprocal_scale(hash, map->len)];
3604 if (cpu_online(tcpu)) {
3614 #ifdef CONFIG_RFS_ACCEL
3617 * rps_may_expire_flow - check whether an RFS hardware filter may be removed
3618 * @dev: Device on which the filter was set
3619 * @rxq_index: RX queue index
3620 * @flow_id: Flow ID passed to ndo_rx_flow_steer()
3621 * @filter_id: Filter ID returned by ndo_rx_flow_steer()
3623 * Drivers that implement ndo_rx_flow_steer() should periodically call
3624 * this function for each installed filter and remove the filters for
3625 * which it returns %true.
3627 bool rps_may_expire_flow(struct net_device *dev, u16 rxq_index,
3628 u32 flow_id, u16 filter_id)
3630 struct netdev_rx_queue *rxqueue = dev->_rx + rxq_index;
3631 struct rps_dev_flow_table *flow_table;
3632 struct rps_dev_flow *rflow;
3637 flow_table = rcu_dereference(rxqueue->rps_flow_table);
3638 if (flow_table && flow_id <= flow_table->mask) {
3639 rflow = &flow_table->flows[flow_id];
3640 cpu = ACCESS_ONCE(rflow->cpu);
3641 if (rflow->filter == filter_id && cpu < nr_cpu_ids &&
3642 ((int)(per_cpu(softnet_data, cpu).input_queue_head -
3643 rflow->last_qtail) <
3644 (int)(10 * flow_table->mask)))
3650 EXPORT_SYMBOL(rps_may_expire_flow);
3652 #endif /* CONFIG_RFS_ACCEL */
3654 /* Called from hardirq (IPI) context */
3655 static void rps_trigger_softirq(void *data)
3657 struct softnet_data *sd = data;
3659 ____napi_schedule(sd, &sd->backlog);
3663 #endif /* CONFIG_RPS */
3666 * Check if this softnet_data structure is another cpu one
3667 * If yes, queue it to our IPI list and return 1
3670 static int rps_ipi_queued(struct softnet_data *sd)
3673 struct softnet_data *mysd = this_cpu_ptr(&softnet_data);
3676 sd->rps_ipi_next = mysd->rps_ipi_list;
3677 mysd->rps_ipi_list = sd;
3679 __raise_softirq_irqoff(NET_RX_SOFTIRQ);
3682 #endif /* CONFIG_RPS */
3686 #ifdef CONFIG_NET_FLOW_LIMIT
3687 int netdev_flow_limit_table_len __read_mostly = (1 << 12);
3690 static bool skb_flow_limit(struct sk_buff *skb, unsigned int qlen)
3692 #ifdef CONFIG_NET_FLOW_LIMIT
3693 struct sd_flow_limit *fl;
3694 struct softnet_data *sd;
3695 unsigned int old_flow, new_flow;
3697 if (qlen < (netdev_max_backlog >> 1))
3700 sd = this_cpu_ptr(&softnet_data);
3703 fl = rcu_dereference(sd->flow_limit);
3705 new_flow = skb_get_hash(skb) & (fl->num_buckets - 1);
3706 old_flow = fl->history[fl->history_head];
3707 fl->history[fl->history_head] = new_flow;
3710 fl->history_head &= FLOW_LIMIT_HISTORY - 1;
3712 if (likely(fl->buckets[old_flow]))
3713 fl->buckets[old_flow]--;
3715 if (++fl->buckets[new_flow] > (FLOW_LIMIT_HISTORY >> 1)) {
3727 * enqueue_to_backlog is called to queue an skb to a per CPU backlog
3728 * queue (may be a remote CPU queue).
3730 static int enqueue_to_backlog(struct sk_buff *skb, int cpu,
3731 unsigned int *qtail)
3733 struct softnet_data *sd;
3734 unsigned long flags;
3737 sd = &per_cpu(softnet_data, cpu);
3739 local_irq_save(flags);
3742 if (!netif_running(skb->dev))
3744 qlen = skb_queue_len(&sd->input_pkt_queue);
3745 if (qlen <= netdev_max_backlog && !skb_flow_limit(skb, qlen)) {
3748 __skb_queue_tail(&sd->input_pkt_queue, skb);
3749 input_queue_tail_incr_save(sd, qtail);
3751 local_irq_restore(flags);
3752 return NET_RX_SUCCESS;
3755 /* Schedule NAPI for backlog device
3756 * We can use non atomic operation since we own the queue lock
3758 if (!__test_and_set_bit(NAPI_STATE_SCHED, &sd->backlog.state)) {
3759 if (!rps_ipi_queued(sd))
3760 ____napi_schedule(sd, &sd->backlog);
3769 local_irq_restore(flags);
3771 atomic_long_inc(&skb->dev->rx_dropped);
3776 static int netif_rx_internal(struct sk_buff *skb)
3780 net_timestamp_check(netdev_tstamp_prequeue, skb);
3782 trace_netif_rx(skb);
3784 if (static_key_false(&rps_needed)) {
3785 struct rps_dev_flow voidflow, *rflow = &voidflow;
3791 cpu = get_rps_cpu(skb->dev, skb, &rflow);
3793 cpu = smp_processor_id();
3795 ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail);
3803 ret = enqueue_to_backlog(skb, get_cpu(), &qtail);
3810 * netif_rx - post buffer to the network code
3811 * @skb: buffer to post
3813 * This function receives a packet from a device driver and queues it for
3814 * the upper (protocol) levels to process. It always succeeds. The buffer
3815 * may be dropped during processing for congestion control or by the
3819 * NET_RX_SUCCESS (no congestion)
3820 * NET_RX_DROP (packet was dropped)
3824 int netif_rx(struct sk_buff *skb)
3826 trace_netif_rx_entry(skb);
3828 return netif_rx_internal(skb);
3830 EXPORT_SYMBOL(netif_rx);
3832 int netif_rx_ni(struct sk_buff *skb)
3836 trace_netif_rx_ni_entry(skb);
3839 err = netif_rx_internal(skb);
3840 if (local_softirq_pending())
3846 EXPORT_SYMBOL(netif_rx_ni);
3848 static void net_tx_action(struct softirq_action *h)
3850 struct softnet_data *sd = this_cpu_ptr(&softnet_data);
3852 if (sd->completion_queue) {
3853 struct sk_buff *clist;
3855 local_irq_disable();
3856 clist = sd->completion_queue;
3857 sd->completion_queue = NULL;
3861 struct sk_buff *skb = clist;
3862 clist = clist->next;
3864 WARN_ON(atomic_read(&skb->users));
3865 if (likely(get_kfree_skb_cb(skb)->reason == SKB_REASON_CONSUMED))
3866 trace_consume_skb(skb);
3868 trace_kfree_skb(skb, net_tx_action);
3870 if (skb->fclone != SKB_FCLONE_UNAVAILABLE)
3873 __kfree_skb_defer(skb);
3876 __kfree_skb_flush();
3879 if (sd->output_queue) {
3882 local_irq_disable();
3883 head = sd->output_queue;
3884 sd->output_queue = NULL;
3885 sd->output_queue_tailp = &sd->output_queue;
3889 struct Qdisc *q = head;
3890 spinlock_t *root_lock;
3892 head = head->next_sched;
3894 root_lock = qdisc_lock(q);
3895 spin_lock(root_lock);
3896 /* We need to make sure head->next_sched is read
3897 * before clearing __QDISC_STATE_SCHED
3899 smp_mb__before_atomic();
3900 clear_bit(__QDISC_STATE_SCHED, &q->state);
3902 spin_unlock(root_lock);
3907 #if IS_ENABLED(CONFIG_BRIDGE) && IS_ENABLED(CONFIG_ATM_LANE)
3908 /* This hook is defined here for ATM LANE */
3909 int (*br_fdb_test_addr_hook)(struct net_device *dev,
3910 unsigned char *addr) __read_mostly;
3911 EXPORT_SYMBOL_GPL(br_fdb_test_addr_hook);
3914 static inline struct sk_buff *
3915 sch_handle_ingress(struct sk_buff *skb, struct packet_type **pt_prev, int *ret,
3916 struct net_device *orig_dev)
3918 #ifdef CONFIG_NET_CLS_ACT
3919 struct tcf_proto *cl = rcu_dereference_bh(skb->dev->ingress_cl_list);
3920 struct tcf_result cl_res;
3922 /* If there's at least one ingress present somewhere (so
3923 * we get here via enabled static key), remaining devices
3924 * that are not configured with an ingress qdisc will bail
3930 *ret = deliver_skb(skb, *pt_prev, orig_dev);
3934 qdisc_skb_cb(skb)->pkt_len = skb->len;
3935 skb->tc_verd = SET_TC_AT(skb->tc_verd, AT_INGRESS);
3936 qdisc_bstats_cpu_update(cl->q, skb);
3938 switch (tc_classify(skb, cl, &cl_res, false)) {
3940 case TC_ACT_RECLASSIFY:
3941 skb->tc_index = TC_H_MIN(cl_res.classid);
3944 qdisc_qstats_cpu_drop(cl->q);
3951 case TC_ACT_REDIRECT:
3952 /* skb_mac_header check was done by cls/act_bpf, so
3953 * we can safely push the L2 header back before
3954 * redirecting to another netdev
3956 __skb_push(skb, skb->mac_len);
3957 skb_do_redirect(skb);
3962 #endif /* CONFIG_NET_CLS_ACT */
3967 * netdev_is_rx_handler_busy - check if receive handler is registered
3968 * @dev: device to check
3970 * Check if a receive handler is already registered for a given device.
3971 * Return true if there one.
3973 * The caller must hold the rtnl_mutex.
3975 bool netdev_is_rx_handler_busy(struct net_device *dev)
3978 return dev && rtnl_dereference(dev->rx_handler);
3980 EXPORT_SYMBOL_GPL(netdev_is_rx_handler_busy);
3983 * netdev_rx_handler_register - register receive handler
3984 * @dev: device to register a handler for
3985 * @rx_handler: receive handler to register
3986 * @rx_handler_data: data pointer that is used by rx handler
3988 * Register a receive handler for a device. This handler will then be
3989 * called from __netif_receive_skb. A negative errno code is returned
3992 * The caller must hold the rtnl_mutex.
3994 * For a general description of rx_handler, see enum rx_handler_result.
3996 int netdev_rx_handler_register(struct net_device *dev,
3997 rx_handler_func_t *rx_handler,
3998 void *rx_handler_data)
4002 if (dev->rx_handler)
4005 /* Note: rx_handler_data must be set before rx_handler */
4006 rcu_assign_pointer(dev->rx_handler_data, rx_handler_data);
4007 rcu_assign_pointer(dev->rx_handler, rx_handler);
4011 EXPORT_SYMBOL_GPL(netdev_rx_handler_register);
4014 * netdev_rx_handler_unregister - unregister receive handler
4015 * @dev: device to unregister a handler from
4017 * Unregister a receive handler from a device.
4019 * The caller must hold the rtnl_mutex.
4021 void netdev_rx_handler_unregister(struct net_device *dev)
4025 RCU_INIT_POINTER(dev->rx_handler, NULL);
4026 /* a reader seeing a non NULL rx_handler in a rcu_read_lock()
4027 * section has a guarantee to see a non NULL rx_handler_data
4031 RCU_INIT_POINTER(dev->rx_handler_data, NULL);
4033 EXPORT_SYMBOL_GPL(netdev_rx_handler_unregister);
4036 * Limit the use of PFMEMALLOC reserves to those protocols that implement
4037 * the special handling of PFMEMALLOC skbs.
4039 static bool skb_pfmemalloc_protocol(struct sk_buff *skb)
4041 switch (skb->protocol) {
4042 case htons(ETH_P_ARP):
4043 case htons(ETH_P_IP):
4044 case htons(ETH_P_IPV6):
4045 case htons(ETH_P_8021Q):
4046 case htons(ETH_P_8021AD):
4053 static inline int nf_ingress(struct sk_buff *skb, struct packet_type **pt_prev,
4054 int *ret, struct net_device *orig_dev)
4056 #ifdef CONFIG_NETFILTER_INGRESS
4057 if (nf_hook_ingress_active(skb)) {
4061 *ret = deliver_skb(skb, *pt_prev, orig_dev);
4066 ingress_retval = nf_hook_ingress(skb);
4068 return ingress_retval;
4070 #endif /* CONFIG_NETFILTER_INGRESS */
4074 static int __netif_receive_skb_core(struct sk_buff *skb, bool pfmemalloc)
4076 struct packet_type *ptype, *pt_prev;
4077 rx_handler_func_t *rx_handler;
4078 struct net_device *orig_dev;
4079 bool deliver_exact = false;
4080 int ret = NET_RX_DROP;
4083 net_timestamp_check(!netdev_tstamp_prequeue, skb);
4085 trace_netif_receive_skb(skb);
4087 orig_dev = skb->dev;
4089 skb_reset_network_header(skb);
4090 if (!skb_transport_header_was_set(skb))
4091 skb_reset_transport_header(skb);
4092 skb_reset_mac_len(skb);
4097 skb->skb_iif = skb->dev->ifindex;
4099 __this_cpu_inc(softnet_data.processed);
4101 if (skb->protocol == cpu_to_be16(ETH_P_8021Q) ||
4102 skb->protocol == cpu_to_be16(ETH_P_8021AD)) {
4103 skb = skb_vlan_untag(skb);
4108 #ifdef CONFIG_NET_CLS_ACT
4109 if (skb->tc_verd & TC_NCLS) {
4110 skb->tc_verd = CLR_TC_NCLS(skb->tc_verd);
4118 list_for_each_entry_rcu(ptype, &ptype_all, list) {
4120 ret = deliver_skb(skb, pt_prev, orig_dev);
4124 list_for_each_entry_rcu(ptype, &skb->dev->ptype_all, list) {
4126 ret = deliver_skb(skb, pt_prev, orig_dev);
4131 #ifdef CONFIG_NET_INGRESS
4132 if (static_key_false(&ingress_needed)) {
4133 skb = sch_handle_ingress(skb, &pt_prev, &ret, orig_dev);
4137 if (nf_ingress(skb, &pt_prev, &ret, orig_dev) < 0)
4141 #ifdef CONFIG_NET_CLS_ACT
4145 if (pfmemalloc && !skb_pfmemalloc_protocol(skb))
4148 if (skb_vlan_tag_present(skb)) {
4150 ret = deliver_skb(skb, pt_prev, orig_dev);
4153 if (vlan_do_receive(&skb))
4155 else if (unlikely(!skb))
4159 rx_handler = rcu_dereference(skb->dev->rx_handler);
4162 ret = deliver_skb(skb, pt_prev, orig_dev);
4165 switch (rx_handler(&skb)) {
4166 case RX_HANDLER_CONSUMED:
4167 ret = NET_RX_SUCCESS;
4169 case RX_HANDLER_ANOTHER:
4171 case RX_HANDLER_EXACT:
4172 deliver_exact = true;
4173 case RX_HANDLER_PASS:
4180 if (unlikely(skb_vlan_tag_present(skb))) {
4181 if (skb_vlan_tag_get_id(skb))
4182 skb->pkt_type = PACKET_OTHERHOST;
4183 /* Note: we might in the future use prio bits
4184 * and set skb->priority like in vlan_do_receive()
4185 * For the time being, just ignore Priority Code Point
4190 type = skb->protocol;
4192 /* deliver only exact match when indicated */
4193 if (likely(!deliver_exact)) {
4194 deliver_ptype_list_skb(skb, &pt_prev, orig_dev, type,
4195 &ptype_base[ntohs(type) &
4199 deliver_ptype_list_skb(skb, &pt_prev, orig_dev, type,
4200 &orig_dev->ptype_specific);
4202 if (unlikely(skb->dev != orig_dev)) {
4203 deliver_ptype_list_skb(skb, &pt_prev, orig_dev, type,
4204 &skb->dev->ptype_specific);
4208 if (unlikely(skb_orphan_frags(skb, GFP_ATOMIC)))
4211 ret = pt_prev->func(skb, skb->dev, pt_prev, orig_dev);
4215 atomic_long_inc(&skb->dev->rx_dropped);
4217 atomic_long_inc(&skb->dev->rx_nohandler);
4219 /* Jamal, now you will not able to escape explaining
4220 * me how you were going to use this. :-)
4229 static int __netif_receive_skb(struct sk_buff *skb)
4233 if (sk_memalloc_socks() && skb_pfmemalloc(skb)) {
4234 unsigned long pflags = current->flags;
4237 * PFMEMALLOC skbs are special, they should
4238 * - be delivered to SOCK_MEMALLOC sockets only
4239 * - stay away from userspace
4240 * - have bounded memory usage
4242 * Use PF_MEMALLOC as this saves us from propagating the allocation
4243 * context down to all allocation sites.
4245 current->flags |= PF_MEMALLOC;
4246 ret = __netif_receive_skb_core(skb, true);
4247 tsk_restore_flags(current, pflags, PF_MEMALLOC);
4249 ret = __netif_receive_skb_core(skb, false);
4254 static int netif_receive_skb_internal(struct sk_buff *skb)
4258 net_timestamp_check(netdev_tstamp_prequeue, skb);
4260 if (skb_defer_rx_timestamp(skb))
4261 return NET_RX_SUCCESS;
4266 if (static_key_false(&rps_needed)) {
4267 struct rps_dev_flow voidflow, *rflow = &voidflow;
4268 int cpu = get_rps_cpu(skb->dev, skb, &rflow);
4271 ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail);
4277 ret = __netif_receive_skb(skb);
4283 * netif_receive_skb - process receive buffer from network
4284 * @skb: buffer to process
4286 * netif_receive_skb() is the main receive data processing function.
4287 * It always succeeds. The buffer may be dropped during processing
4288 * for congestion control or by the protocol layers.
4290 * This function may only be called from softirq context and interrupts
4291 * should be enabled.
4293 * Return values (usually ignored):
4294 * NET_RX_SUCCESS: no congestion
4295 * NET_RX_DROP: packet was dropped
4297 int netif_receive_skb(struct sk_buff *skb)
4299 trace_netif_receive_skb_entry(skb);
4301 return netif_receive_skb_internal(skb);
4303 EXPORT_SYMBOL(netif_receive_skb);
4305 DEFINE_PER_CPU(struct work_struct, flush_works);
4307 /* Network device is going away, flush any packets still pending */
4308 static void flush_backlog(struct work_struct *work)
4310 struct sk_buff *skb, *tmp;
4311 struct softnet_data *sd;
4314 sd = this_cpu_ptr(&softnet_data);
4316 local_irq_disable();
4318 skb_queue_walk_safe(&sd->input_pkt_queue, skb, tmp) {
4319 if (skb->dev->reg_state == NETREG_UNREGISTERING) {
4320 __skb_unlink(skb, &sd->input_pkt_queue);
4322 input_queue_head_incr(sd);
4328 skb_queue_walk_safe(&sd->process_queue, skb, tmp) {
4329 if (skb->dev->reg_state == NETREG_UNREGISTERING) {
4330 __skb_unlink(skb, &sd->process_queue);
4332 input_queue_head_incr(sd);
4338 static void flush_all_backlogs(void)
4344 for_each_online_cpu(cpu)
4345 queue_work_on(cpu, system_highpri_wq,
4346 per_cpu_ptr(&flush_works, cpu));
4348 for_each_online_cpu(cpu)
4349 flush_work(per_cpu_ptr(&flush_works, cpu));
4354 static int napi_gro_complete(struct sk_buff *skb)
4356 struct packet_offload *ptype;
4357 __be16 type = skb->protocol;
4358 struct list_head *head = &offload_base;
4361 BUILD_BUG_ON(sizeof(struct napi_gro_cb) > sizeof(skb->cb));
4363 if (NAPI_GRO_CB(skb)->count == 1) {
4364 skb_shinfo(skb)->gso_size = 0;
4369 list_for_each_entry_rcu(ptype, head, list) {
4370 if (ptype->type != type || !ptype->callbacks.gro_complete)
4373 err = ptype->callbacks.gro_complete(skb, 0);
4379 WARN_ON(&ptype->list == head);
4381 return NET_RX_SUCCESS;
4385 return netif_receive_skb_internal(skb);
4388 /* napi->gro_list contains packets ordered by age.
4389 * youngest packets at the head of it.
4390 * Complete skbs in reverse order to reduce latencies.
4392 void napi_gro_flush(struct napi_struct *napi, bool flush_old)
4394 struct sk_buff *skb, *prev = NULL;
4396 /* scan list and build reverse chain */
4397 for (skb = napi->gro_list; skb != NULL; skb = skb->next) {
4402 for (skb = prev; skb; skb = prev) {
4405 if (flush_old && NAPI_GRO_CB(skb)->age == jiffies)
4409 napi_gro_complete(skb);
4413 napi->gro_list = NULL;
4415 EXPORT_SYMBOL(napi_gro_flush);
4417 static void gro_list_prepare(struct napi_struct *napi, struct sk_buff *skb)
4420 unsigned int maclen = skb->dev->hard_header_len;
4421 u32 hash = skb_get_hash_raw(skb);
4423 for (p = napi->gro_list; p; p = p->next) {
4424 unsigned long diffs;
4426 NAPI_GRO_CB(p)->flush = 0;
4428 if (hash != skb_get_hash_raw(p)) {
4429 NAPI_GRO_CB(p)->same_flow = 0;
4433 diffs = (unsigned long)p->dev ^ (unsigned long)skb->dev;
4434 diffs |= p->vlan_tci ^ skb->vlan_tci;
4435 diffs |= skb_metadata_dst_cmp(p, skb);
4436 if (maclen == ETH_HLEN)
4437 diffs |= compare_ether_header(skb_mac_header(p),
4438 skb_mac_header(skb));
4440 diffs = memcmp(skb_mac_header(p),
4441 skb_mac_header(skb),
4443 NAPI_GRO_CB(p)->same_flow = !diffs;
4447 static void skb_gro_reset_offset(struct sk_buff *skb)
4449 const struct skb_shared_info *pinfo = skb_shinfo(skb);
4450 const skb_frag_t *frag0 = &pinfo->frags[0];
4452 NAPI_GRO_CB(skb)->data_offset = 0;
4453 NAPI_GRO_CB(skb)->frag0 = NULL;
4454 NAPI_GRO_CB(skb)->frag0_len = 0;
4456 if (skb_mac_header(skb) == skb_tail_pointer(skb) &&
4458 !PageHighMem(skb_frag_page(frag0))) {
4459 NAPI_GRO_CB(skb)->frag0 = skb_frag_address(frag0);
4460 NAPI_GRO_CB(skb)->frag0_len = skb_frag_size(frag0);
4464 static void gro_pull_from_frag0(struct sk_buff *skb, int grow)
4466 struct skb_shared_info *pinfo = skb_shinfo(skb);
4468 BUG_ON(skb->end - skb->tail < grow);
4470 memcpy(skb_tail_pointer(skb), NAPI_GRO_CB(skb)->frag0, grow);
4472 skb->data_len -= grow;
4475 pinfo->frags[0].page_offset += grow;
4476 skb_frag_size_sub(&pinfo->frags[0], grow);
4478 if (unlikely(!skb_frag_size(&pinfo->frags[0]))) {
4479 skb_frag_unref(skb, 0);
4480 memmove(pinfo->frags, pinfo->frags + 1,
4481 --pinfo->nr_frags * sizeof(pinfo->frags[0]));
4485 static enum gro_result dev_gro_receive(struct napi_struct *napi, struct sk_buff *skb)
4487 struct sk_buff **pp = NULL;
4488 struct packet_offload *ptype;
4489 __be16 type = skb->protocol;
4490 struct list_head *head = &offload_base;
4492 enum gro_result ret;
4495 if (!(skb->dev->features & NETIF_F_GRO))
4498 if (skb_is_gso(skb) || skb_has_frag_list(skb) || skb->csum_bad)
4501 gro_list_prepare(napi, skb);
4504 list_for_each_entry_rcu(ptype, head, list) {
4505 if (ptype->type != type || !ptype->callbacks.gro_receive)
4508 skb_set_network_header(skb, skb_gro_offset(skb));
4509 skb_reset_mac_len(skb);
4510 NAPI_GRO_CB(skb)->same_flow = 0;
4511 NAPI_GRO_CB(skb)->flush = 0;
4512 NAPI_GRO_CB(skb)->free = 0;
4513 NAPI_GRO_CB(skb)->encap_mark = 0;
4514 NAPI_GRO_CB(skb)->recursion_counter = 0;
4515 NAPI_GRO_CB(skb)->is_fou = 0;
4516 NAPI_GRO_CB(skb)->is_atomic = 1;
4517 NAPI_GRO_CB(skb)->gro_remcsum_start = 0;
4519 /* Setup for GRO checksum validation */
4520 switch (skb->ip_summed) {
4521 case CHECKSUM_COMPLETE:
4522 NAPI_GRO_CB(skb)->csum = skb->csum;
4523 NAPI_GRO_CB(skb)->csum_valid = 1;
4524 NAPI_GRO_CB(skb)->csum_cnt = 0;
4526 case CHECKSUM_UNNECESSARY:
4527 NAPI_GRO_CB(skb)->csum_cnt = skb->csum_level + 1;
4528 NAPI_GRO_CB(skb)->csum_valid = 0;
4531 NAPI_GRO_CB(skb)->csum_cnt = 0;
4532 NAPI_GRO_CB(skb)->csum_valid = 0;
4535 pp = ptype->callbacks.gro_receive(&napi->gro_list, skb);
4540 if (&ptype->list == head)
4543 same_flow = NAPI_GRO_CB(skb)->same_flow;
4544 ret = NAPI_GRO_CB(skb)->free ? GRO_MERGED_FREE : GRO_MERGED;
4547 struct sk_buff *nskb = *pp;
4551 napi_gro_complete(nskb);
4558 if (NAPI_GRO_CB(skb)->flush)
4561 if (unlikely(napi->gro_count >= MAX_GRO_SKBS)) {
4562 struct sk_buff *nskb = napi->gro_list;
4564 /* locate the end of the list to select the 'oldest' flow */
4565 while (nskb->next) {
4571 napi_gro_complete(nskb);
4575 NAPI_GRO_CB(skb)->count = 1;
4576 NAPI_GRO_CB(skb)->age = jiffies;
4577 NAPI_GRO_CB(skb)->last = skb;
4578 skb_shinfo(skb)->gso_size = skb_gro_len(skb);
4579 skb->next = napi->gro_list;
4580 napi->gro_list = skb;
4584 grow = skb_gro_offset(skb) - skb_headlen(skb);
4586 gro_pull_from_frag0(skb, grow);
4595 struct packet_offload *gro_find_receive_by_type(__be16 type)
4597 struct list_head *offload_head = &offload_base;
4598 struct packet_offload *ptype;
4600 list_for_each_entry_rcu(ptype, offload_head, list) {
4601 if (ptype->type != type || !ptype->callbacks.gro_receive)
4607 EXPORT_SYMBOL(gro_find_receive_by_type);
4609 struct packet_offload *gro_find_complete_by_type(__be16 type)
4611 struct list_head *offload_head = &offload_base;
4612 struct packet_offload *ptype;
4614 list_for_each_entry_rcu(ptype, offload_head, list) {
4615 if (ptype->type != type || !ptype->callbacks.gro_complete)
4621 EXPORT_SYMBOL(gro_find_complete_by_type);
4623 static gro_result_t napi_skb_finish(gro_result_t ret, struct sk_buff *skb)
4627 if (netif_receive_skb_internal(skb))
4635 case GRO_MERGED_FREE:
4636 if (NAPI_GRO_CB(skb)->free == NAPI_GRO_FREE_STOLEN_HEAD) {
4638 kmem_cache_free(skbuff_head_cache, skb);
4652 gro_result_t napi_gro_receive(struct napi_struct *napi, struct sk_buff *skb)
4654 skb_mark_napi_id(skb, napi);
4655 trace_napi_gro_receive_entry(skb);
4657 skb_gro_reset_offset(skb);
4659 return napi_skb_finish(dev_gro_receive(napi, skb), skb);
4661 EXPORT_SYMBOL(napi_gro_receive);
4663 static void napi_reuse_skb(struct napi_struct *napi, struct sk_buff *skb)
4665 if (unlikely(skb->pfmemalloc)) {
4669 __skb_pull(skb, skb_headlen(skb));
4670 /* restore the reserve we had after netdev_alloc_skb_ip_align() */
4671 skb_reserve(skb, NET_SKB_PAD + NET_IP_ALIGN - skb_headroom(skb));
4673 skb->dev = napi->dev;
4675 skb->encapsulation = 0;
4676 skb_shinfo(skb)->gso_type = 0;
4677 skb->truesize = SKB_TRUESIZE(skb_end_offset(skb));
4682 struct sk_buff *napi_get_frags(struct napi_struct *napi)
4684 struct sk_buff *skb = napi->skb;
4687 skb = napi_alloc_skb(napi, GRO_MAX_HEAD);
4690 skb_mark_napi_id(skb, napi);
4695 EXPORT_SYMBOL(napi_get_frags);
4697 static gro_result_t napi_frags_finish(struct napi_struct *napi,
4698 struct sk_buff *skb,
4704 __skb_push(skb, ETH_HLEN);
4705 skb->protocol = eth_type_trans(skb, skb->dev);
4706 if (ret == GRO_NORMAL && netif_receive_skb_internal(skb))
4711 case GRO_MERGED_FREE:
4712 napi_reuse_skb(napi, skb);
4722 /* Upper GRO stack assumes network header starts at gro_offset=0
4723 * Drivers could call both napi_gro_frags() and napi_gro_receive()
4724 * We copy ethernet header into skb->data to have a common layout.
4726 static struct sk_buff *napi_frags_skb(struct napi_struct *napi)
4728 struct sk_buff *skb = napi->skb;
4729 const struct ethhdr *eth;
4730 unsigned int hlen = sizeof(*eth);
4734 skb_reset_mac_header(skb);
4735 skb_gro_reset_offset(skb);
4737 eth = skb_gro_header_fast(skb, 0);
4738 if (unlikely(skb_gro_header_hard(skb, hlen))) {
4739 eth = skb_gro_header_slow(skb, hlen, 0);
4740 if (unlikely(!eth)) {
4741 net_warn_ratelimited("%s: dropping impossible skb from %s\n",
4742 __func__, napi->dev->name);
4743 napi_reuse_skb(napi, skb);
4747 gro_pull_from_frag0(skb, hlen);
4748 NAPI_GRO_CB(skb)->frag0 += hlen;
4749 NAPI_GRO_CB(skb)->frag0_len -= hlen;
4751 __skb_pull(skb, hlen);
4754 * This works because the only protocols we care about don't require
4756 * We'll fix it up properly in napi_frags_finish()
4758 skb->protocol = eth->h_proto;
4763 gro_result_t napi_gro_frags(struct napi_struct *napi)
4765 struct sk_buff *skb = napi_frags_skb(napi);
4770 trace_napi_gro_frags_entry(skb);
4772 return napi_frags_finish(napi, skb, dev_gro_receive(napi, skb));
4774 EXPORT_SYMBOL(napi_gro_frags);
4776 /* Compute the checksum from gro_offset and return the folded value
4777 * after adding in any pseudo checksum.
4779 __sum16 __skb_gro_checksum_complete(struct sk_buff *skb)
4784 wsum = skb_checksum(skb, skb_gro_offset(skb), skb_gro_len(skb), 0);
4786 /* NAPI_GRO_CB(skb)->csum holds pseudo checksum */
4787 sum = csum_fold(csum_add(NAPI_GRO_CB(skb)->csum, wsum));
4789 if (unlikely(skb->ip_summed == CHECKSUM_COMPLETE) &&
4790 !skb->csum_complete_sw)
4791 netdev_rx_csum_fault(skb->dev);
4794 NAPI_GRO_CB(skb)->csum = wsum;
4795 NAPI_GRO_CB(skb)->csum_valid = 1;
4799 EXPORT_SYMBOL(__skb_gro_checksum_complete);
4802 * net_rps_action_and_irq_enable sends any pending IPI's for rps.
4803 * Note: called with local irq disabled, but exits with local irq enabled.
4805 static void net_rps_action_and_irq_enable(struct softnet_data *sd)
4808 struct softnet_data *remsd = sd->rps_ipi_list;
4811 sd->rps_ipi_list = NULL;
4815 /* Send pending IPI's to kick RPS processing on remote cpus. */
4817 struct softnet_data *next = remsd->rps_ipi_next;
4819 if (cpu_online(remsd->cpu))
4820 smp_call_function_single_async(remsd->cpu,
4829 static bool sd_has_rps_ipi_waiting(struct softnet_data *sd)
4832 return sd->rps_ipi_list != NULL;
4838 static int process_backlog(struct napi_struct *napi, int quota)
4840 struct softnet_data *sd = container_of(napi, struct softnet_data, backlog);
4844 /* Check if we have pending ipi, its better to send them now,
4845 * not waiting net_rx_action() end.
4847 if (sd_has_rps_ipi_waiting(sd)) {
4848 local_irq_disable();
4849 net_rps_action_and_irq_enable(sd);
4852 napi->weight = weight_p;
4854 struct sk_buff *skb;
4856 while ((skb = __skb_dequeue(&sd->process_queue))) {
4858 __netif_receive_skb(skb);
4860 input_queue_head_incr(sd);
4861 if (++work >= quota)
4866 local_irq_disable();
4868 if (skb_queue_empty(&sd->input_pkt_queue)) {
4870 * Inline a custom version of __napi_complete().
4871 * only current cpu owns and manipulates this napi,
4872 * and NAPI_STATE_SCHED is the only possible flag set
4874 * We can use a plain write instead of clear_bit(),
4875 * and we dont need an smp_mb() memory barrier.
4880 skb_queue_splice_tail_init(&sd->input_pkt_queue,
4881 &sd->process_queue);
4891 * __napi_schedule - schedule for receive
4892 * @n: entry to schedule
4894 * The entry's receive function will be scheduled to run.
4895 * Consider using __napi_schedule_irqoff() if hard irqs are masked.
4897 void __napi_schedule(struct napi_struct *n)
4899 unsigned long flags;
4901 local_irq_save(flags);
4902 ____napi_schedule(this_cpu_ptr(&softnet_data), n);
4903 local_irq_restore(flags);
4905 EXPORT_SYMBOL(__napi_schedule);
4908 * __napi_schedule_irqoff - schedule for receive
4909 * @n: entry to schedule
4911 * Variant of __napi_schedule() assuming hard irqs are masked
4913 void __napi_schedule_irqoff(struct napi_struct *n)
4915 ____napi_schedule(this_cpu_ptr(&softnet_data), n);
4917 EXPORT_SYMBOL(__napi_schedule_irqoff);
4919 void __napi_complete(struct napi_struct *n)
4921 BUG_ON(!test_bit(NAPI_STATE_SCHED, &n->state));
4923 list_del_init(&n->poll_list);
4924 smp_mb__before_atomic();
4925 clear_bit(NAPI_STATE_SCHED, &n->state);
4927 EXPORT_SYMBOL(__napi_complete);
4929 void napi_complete_done(struct napi_struct *n, int work_done)
4931 unsigned long flags;
4934 * don't let napi dequeue from the cpu poll list
4935 * just in case its running on a different cpu
4937 if (unlikely(test_bit(NAPI_STATE_NPSVC, &n->state)))
4941 unsigned long timeout = 0;
4944 timeout = n->dev->gro_flush_timeout;
4947 hrtimer_start(&n->timer, ns_to_ktime(timeout),
4948 HRTIMER_MODE_REL_PINNED);
4950 napi_gro_flush(n, false);
4952 if (likely(list_empty(&n->poll_list))) {
4953 WARN_ON_ONCE(!test_and_clear_bit(NAPI_STATE_SCHED, &n->state));
4955 /* If n->poll_list is not empty, we need to mask irqs */
4956 local_irq_save(flags);
4958 local_irq_restore(flags);
4961 EXPORT_SYMBOL(napi_complete_done);
4963 /* must be called under rcu_read_lock(), as we dont take a reference */
4964 static struct napi_struct *napi_by_id(unsigned int napi_id)
4966 unsigned int hash = napi_id % HASH_SIZE(napi_hash);
4967 struct napi_struct *napi;
4969 hlist_for_each_entry_rcu(napi, &napi_hash[hash], napi_hash_node)
4970 if (napi->napi_id == napi_id)
4976 #if defined(CONFIG_NET_RX_BUSY_POLL)
4977 #define BUSY_POLL_BUDGET 8
4978 bool sk_busy_loop(struct sock *sk, int nonblock)
4980 unsigned long end_time = !nonblock ? sk_busy_loop_end_time(sk) : 0;
4981 int (*busy_poll)(struct napi_struct *dev);
4982 struct napi_struct *napi;
4987 napi = napi_by_id(sk->sk_napi_id);
4991 /* Note: ndo_busy_poll method is optional in linux-4.5 */
4992 busy_poll = napi->dev->netdev_ops->ndo_busy_poll;
4998 rc = busy_poll(napi);
4999 } else if (napi_schedule_prep(napi)) {
5000 void *have = netpoll_poll_lock(napi);
5002 if (test_bit(NAPI_STATE_SCHED, &napi->state)) {
5003 rc = napi->poll(napi, BUSY_POLL_BUDGET);
5004 trace_napi_poll(napi, rc, BUSY_POLL_BUDGET);
5005 if (rc == BUSY_POLL_BUDGET) {
5006 napi_complete_done(napi, rc);
5007 napi_schedule(napi);
5010 netpoll_poll_unlock(have);
5013 __NET_ADD_STATS(sock_net(sk),
5014 LINUX_MIB_BUSYPOLLRXPACKETS, rc);
5017 if (rc == LL_FLUSH_FAILED)
5018 break; /* permanent failure */
5021 } while (!nonblock && skb_queue_empty(&sk->sk_receive_queue) &&
5022 !need_resched() && !busy_loop_timeout(end_time));
5024 rc = !skb_queue_empty(&sk->sk_receive_queue);
5029 EXPORT_SYMBOL(sk_busy_loop);
5031 #endif /* CONFIG_NET_RX_BUSY_POLL */
5033 void napi_hash_add(struct napi_struct *napi)
5035 if (test_bit(NAPI_STATE_NO_BUSY_POLL, &napi->state) ||
5036 test_and_set_bit(NAPI_STATE_HASHED, &napi->state))
5039 spin_lock(&napi_hash_lock);
5041 /* 0..NR_CPUS+1 range is reserved for sender_cpu use */
5043 if (unlikely(++napi_gen_id < NR_CPUS + 1))
5044 napi_gen_id = NR_CPUS + 1;
5045 } while (napi_by_id(napi_gen_id));
5046 napi->napi_id = napi_gen_id;
5048 hlist_add_head_rcu(&napi->napi_hash_node,
5049 &napi_hash[napi->napi_id % HASH_SIZE(napi_hash)]);
5051 spin_unlock(&napi_hash_lock);
5053 EXPORT_SYMBOL_GPL(napi_hash_add);
5055 /* Warning : caller is responsible to make sure rcu grace period
5056 * is respected before freeing memory containing @napi
5058 bool napi_hash_del(struct napi_struct *napi)
5060 bool rcu_sync_needed = false;
5062 spin_lock(&napi_hash_lock);
5064 if (test_and_clear_bit(NAPI_STATE_HASHED, &napi->state)) {
5065 rcu_sync_needed = true;
5066 hlist_del_rcu(&napi->napi_hash_node);
5068 spin_unlock(&napi_hash_lock);
5069 return rcu_sync_needed;
5071 EXPORT_SYMBOL_GPL(napi_hash_del);
5073 static enum hrtimer_restart napi_watchdog(struct hrtimer *timer)
5075 struct napi_struct *napi;
5077 napi = container_of(timer, struct napi_struct, timer);
5079 napi_schedule(napi);
5081 return HRTIMER_NORESTART;
5084 void netif_napi_add(struct net_device *dev, struct napi_struct *napi,
5085 int (*poll)(struct napi_struct *, int), int weight)
5087 INIT_LIST_HEAD(&napi->poll_list);
5088 hrtimer_init(&napi->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_PINNED);
5089 napi->timer.function = napi_watchdog;
5090 napi->gro_count = 0;
5091 napi->gro_list = NULL;
5094 if (weight > NAPI_POLL_WEIGHT)
5095 pr_err_once("netif_napi_add() called with weight %d on device %s\n",
5097 napi->weight = weight;
5098 list_add(&napi->dev_list, &dev->napi_list);
5100 #ifdef CONFIG_NETPOLL
5101 spin_lock_init(&napi->poll_lock);
5102 napi->poll_owner = -1;
5104 set_bit(NAPI_STATE_SCHED, &napi->state);
5105 napi_hash_add(napi);
5107 EXPORT_SYMBOL(netif_napi_add);
5109 void napi_disable(struct napi_struct *n)
5112 set_bit(NAPI_STATE_DISABLE, &n->state);
5114 while (test_and_set_bit(NAPI_STATE_SCHED, &n->state))
5116 while (test_and_set_bit(NAPI_STATE_NPSVC, &n->state))
5119 hrtimer_cancel(&n->timer);
5121 clear_bit(NAPI_STATE_DISABLE, &n->state);
5123 EXPORT_SYMBOL(napi_disable);
5125 /* Must be called in process context */
5126 void netif_napi_del(struct napi_struct *napi)
5129 if (napi_hash_del(napi))
5131 list_del_init(&napi->dev_list);
5132 napi_free_frags(napi);
5134 kfree_skb_list(napi->gro_list);
5135 napi->gro_list = NULL;
5136 napi->gro_count = 0;
5138 EXPORT_SYMBOL(netif_napi_del);
5140 static int napi_poll(struct napi_struct *n, struct list_head *repoll)
5145 list_del_init(&n->poll_list);
5147 have = netpoll_poll_lock(n);
5151 /* This NAPI_STATE_SCHED test is for avoiding a race
5152 * with netpoll's poll_napi(). Only the entity which
5153 * obtains the lock and sees NAPI_STATE_SCHED set will
5154 * actually make the ->poll() call. Therefore we avoid
5155 * accidentally calling ->poll() when NAPI is not scheduled.
5158 if (test_bit(NAPI_STATE_SCHED, &n->state)) {
5159 work = n->poll(n, weight);
5160 trace_napi_poll(n, work, weight);
5163 WARN_ON_ONCE(work > weight);
5165 if (likely(work < weight))
5168 /* Drivers must not modify the NAPI state if they
5169 * consume the entire weight. In such cases this code
5170 * still "owns" the NAPI instance and therefore can
5171 * move the instance around on the list at-will.
5173 if (unlikely(napi_disable_pending(n))) {
5179 /* flush too old packets
5180 * If HZ < 1000, flush all packets.
5182 napi_gro_flush(n, HZ >= 1000);
5185 /* Some drivers may have called napi_schedule
5186 * prior to exhausting their budget.
5188 if (unlikely(!list_empty(&n->poll_list))) {
5189 pr_warn_once("%s: Budget exhausted after napi rescheduled\n",
5190 n->dev ? n->dev->name : "backlog");
5194 list_add_tail(&n->poll_list, repoll);
5197 netpoll_poll_unlock(have);
5202 static void net_rx_action(struct softirq_action *h)
5204 struct softnet_data *sd = this_cpu_ptr(&softnet_data);
5205 unsigned long time_limit = jiffies + 2;
5206 int budget = netdev_budget;
5210 local_irq_disable();
5211 list_splice_init(&sd->poll_list, &list);
5215 struct napi_struct *n;
5217 if (list_empty(&list)) {
5218 if (!sd_has_rps_ipi_waiting(sd) && list_empty(&repoll))
5223 n = list_first_entry(&list, struct napi_struct, poll_list);
5224 budget -= napi_poll(n, &repoll);
5226 /* If softirq window is exhausted then punt.
5227 * Allow this to run for 2 jiffies since which will allow
5228 * an average latency of 1.5/HZ.
5230 if (unlikely(budget <= 0 ||
5231 time_after_eq(jiffies, time_limit))) {
5237 __kfree_skb_flush();
5238 local_irq_disable();
5240 list_splice_tail_init(&sd->poll_list, &list);
5241 list_splice_tail(&repoll, &list);
5242 list_splice(&list, &sd->poll_list);
5243 if (!list_empty(&sd->poll_list))
5244 __raise_softirq_irqoff(NET_RX_SOFTIRQ);
5246 net_rps_action_and_irq_enable(sd);
5249 struct netdev_adjacent {
5250 struct net_device *dev;
5252 /* upper master flag, there can only be one master device per list */
5255 /* counter for the number of times this device was added to us */
5258 /* private field for the users */
5261 struct list_head list;
5262 struct rcu_head rcu;
5265 static struct netdev_adjacent *__netdev_find_adj(struct net_device *adj_dev,
5266 struct list_head *adj_list)
5268 struct netdev_adjacent *adj;
5270 list_for_each_entry(adj, adj_list, list) {
5271 if (adj->dev == adj_dev)
5278 * netdev_has_upper_dev - Check if device is linked to an upper device
5280 * @upper_dev: upper device to check
5282 * Find out if a device is linked to specified upper device and return true
5283 * in case it is. Note that this checks only immediate upper device,
5284 * not through a complete stack of devices. The caller must hold the RTNL lock.
5286 bool netdev_has_upper_dev(struct net_device *dev,
5287 struct net_device *upper_dev)
5291 return __netdev_find_adj(upper_dev, &dev->all_adj_list.upper);
5293 EXPORT_SYMBOL(netdev_has_upper_dev);
5296 * netdev_has_any_upper_dev - Check if device is linked to some device
5299 * Find out if a device is linked to an upper device and return true in case
5300 * it is. The caller must hold the RTNL lock.
5302 static bool netdev_has_any_upper_dev(struct net_device *dev)
5306 return !list_empty(&dev->all_adj_list.upper);
5310 * netdev_master_upper_dev_get - Get master upper device
5313 * Find a master upper device and return pointer to it or NULL in case
5314 * it's not there. The caller must hold the RTNL lock.
5316 struct net_device *netdev_master_upper_dev_get(struct net_device *dev)
5318 struct netdev_adjacent *upper;
5322 if (list_empty(&dev->adj_list.upper))
5325 upper = list_first_entry(&dev->adj_list.upper,
5326 struct netdev_adjacent, list);
5327 if (likely(upper->master))
5331 EXPORT_SYMBOL(netdev_master_upper_dev_get);
5333 void *netdev_adjacent_get_private(struct list_head *adj_list)
5335 struct netdev_adjacent *adj;
5337 adj = list_entry(adj_list, struct netdev_adjacent, list);
5339 return adj->private;
5341 EXPORT_SYMBOL(netdev_adjacent_get_private);
5344 * netdev_upper_get_next_dev_rcu - Get the next dev from upper list
5346 * @iter: list_head ** of the current position
5348 * Gets the next device from the dev's upper list, starting from iter
5349 * position. The caller must hold RCU read lock.
5351 struct net_device *netdev_upper_get_next_dev_rcu(struct net_device *dev,
5352 struct list_head **iter)
5354 struct netdev_adjacent *upper;
5356 WARN_ON_ONCE(!rcu_read_lock_held() && !lockdep_rtnl_is_held());
5358 upper = list_entry_rcu((*iter)->next, struct netdev_adjacent, list);
5360 if (&upper->list == &dev->adj_list.upper)
5363 *iter = &upper->list;
5367 EXPORT_SYMBOL(netdev_upper_get_next_dev_rcu);
5370 * netdev_all_upper_get_next_dev_rcu - Get the next dev from upper list
5372 * @iter: list_head ** of the current position
5374 * Gets the next device from the dev's upper list, starting from iter
5375 * position. The caller must hold RCU read lock.
5377 struct net_device *netdev_all_upper_get_next_dev_rcu(struct net_device *dev,
5378 struct list_head **iter)
5380 struct netdev_adjacent *upper;
5382 WARN_ON_ONCE(!rcu_read_lock_held() && !lockdep_rtnl_is_held());
5384 upper = list_entry_rcu((*iter)->next, struct netdev_adjacent, list);
5386 if (&upper->list == &dev->all_adj_list.upper)
5389 *iter = &upper->list;
5393 EXPORT_SYMBOL(netdev_all_upper_get_next_dev_rcu);
5396 * netdev_lower_get_next_private - Get the next ->private from the
5397 * lower neighbour list
5399 * @iter: list_head ** of the current position
5401 * Gets the next netdev_adjacent->private from the dev's lower neighbour
5402 * list, starting from iter position. The caller must hold either hold the
5403 * RTNL lock or its own locking that guarantees that the neighbour lower
5404 * list will remain unchanged.
5406 void *netdev_lower_get_next_private(struct net_device *dev,
5407 struct list_head **iter)
5409 struct netdev_adjacent *lower;
5411 lower = list_entry(*iter, struct netdev_adjacent, list);
5413 if (&lower->list == &dev->adj_list.lower)
5416 *iter = lower->list.next;
5418 return lower->private;
5420 EXPORT_SYMBOL(netdev_lower_get_next_private);
5423 * netdev_lower_get_next_private_rcu - Get the next ->private from the
5424 * lower neighbour list, RCU
5427 * @iter: list_head ** of the current position
5429 * Gets the next netdev_adjacent->private from the dev's lower neighbour
5430 * list, starting from iter position. The caller must hold RCU read lock.
5432 void *netdev_lower_get_next_private_rcu(struct net_device *dev,
5433 struct list_head **iter)
5435 struct netdev_adjacent *lower;
5437 WARN_ON_ONCE(!rcu_read_lock_held());
5439 lower = list_entry_rcu((*iter)->next, struct netdev_adjacent, list);
5441 if (&lower->list == &dev->adj_list.lower)
5444 *iter = &lower->list;
5446 return lower->private;
5448 EXPORT_SYMBOL(netdev_lower_get_next_private_rcu);
5451 * netdev_lower_get_next - Get the next device from the lower neighbour
5454 * @iter: list_head ** of the current position
5456 * Gets the next netdev_adjacent from the dev's lower neighbour
5457 * list, starting from iter position. The caller must hold RTNL lock or
5458 * its own locking that guarantees that the neighbour lower
5459 * list will remain unchanged.
5461 void *netdev_lower_get_next(struct net_device *dev, struct list_head **iter)
5463 struct netdev_adjacent *lower;
5465 lower = list_entry(*iter, struct netdev_adjacent, list);
5467 if (&lower->list == &dev->adj_list.lower)
5470 *iter = lower->list.next;
5474 EXPORT_SYMBOL(netdev_lower_get_next);
5477 * netdev_all_lower_get_next - Get the next device from all lower neighbour list
5479 * @iter: list_head ** of the current position
5481 * Gets the next netdev_adjacent from the dev's all lower neighbour
5482 * list, starting from iter position. The caller must hold RTNL lock or
5483 * its own locking that guarantees that the neighbour all lower
5484 * list will remain unchanged.
5486 struct net_device *netdev_all_lower_get_next(struct net_device *dev, struct list_head **iter)
5488 struct netdev_adjacent *lower;
5490 lower = list_entry(*iter, struct netdev_adjacent, list);
5492 if (&lower->list == &dev->all_adj_list.lower)
5495 *iter = lower->list.next;
5499 EXPORT_SYMBOL(netdev_all_lower_get_next);
5502 * netdev_all_lower_get_next_rcu - Get the next device from all
5503 * lower neighbour list, RCU variant
5505 * @iter: list_head ** of the current position
5507 * Gets the next netdev_adjacent from the dev's all lower neighbour
5508 * list, starting from iter position. The caller must hold RCU read lock.
5510 struct net_device *netdev_all_lower_get_next_rcu(struct net_device *dev,
5511 struct list_head **iter)
5513 struct netdev_adjacent *lower;
5515 lower = list_entry_rcu((*iter)->next, struct netdev_adjacent, list);
5517 if (&lower->list == &dev->all_adj_list.lower)
5520 *iter = &lower->list;
5524 EXPORT_SYMBOL(netdev_all_lower_get_next_rcu);
5527 * netdev_lower_get_first_private_rcu - Get the first ->private from the
5528 * lower neighbour list, RCU
5532 * Gets the first netdev_adjacent->private from the dev's lower neighbour
5533 * list. The caller must hold RCU read lock.
5535 void *netdev_lower_get_first_private_rcu(struct net_device *dev)
5537 struct netdev_adjacent *lower;
5539 lower = list_first_or_null_rcu(&dev->adj_list.lower,
5540 struct netdev_adjacent, list);
5542 return lower->private;
5545 EXPORT_SYMBOL(netdev_lower_get_first_private_rcu);
5548 * netdev_master_upper_dev_get_rcu - Get master upper device
5551 * Find a master upper device and return pointer to it or NULL in case
5552 * it's not there. The caller must hold the RCU read lock.
5554 struct net_device *netdev_master_upper_dev_get_rcu(struct net_device *dev)
5556 struct netdev_adjacent *upper;
5558 upper = list_first_or_null_rcu(&dev->adj_list.upper,
5559 struct netdev_adjacent, list);
5560 if (upper && likely(upper->master))
5564 EXPORT_SYMBOL(netdev_master_upper_dev_get_rcu);
5566 static int netdev_adjacent_sysfs_add(struct net_device *dev,
5567 struct net_device *adj_dev,
5568 struct list_head *dev_list)
5570 char linkname[IFNAMSIZ+7];
5571 sprintf(linkname, dev_list == &dev->adj_list.upper ?
5572 "upper_%s" : "lower_%s", adj_dev->name);
5573 return sysfs_create_link(&(dev->dev.kobj), &(adj_dev->dev.kobj),
5576 static void netdev_adjacent_sysfs_del(struct net_device *dev,
5578 struct list_head *dev_list)
5580 char linkname[IFNAMSIZ+7];
5581 sprintf(linkname, dev_list == &dev->adj_list.upper ?
5582 "upper_%s" : "lower_%s", name);
5583 sysfs_remove_link(&(dev->dev.kobj), linkname);
5586 static inline bool netdev_adjacent_is_neigh_list(struct net_device *dev,
5587 struct net_device *adj_dev,
5588 struct list_head *dev_list)
5590 return (dev_list == &dev->adj_list.upper ||
5591 dev_list == &dev->adj_list.lower) &&
5592 net_eq(dev_net(dev), dev_net(adj_dev));
5595 static int __netdev_adjacent_dev_insert(struct net_device *dev,
5596 struct net_device *adj_dev,
5598 struct list_head *dev_list,
5599 void *private, bool master)
5601 struct netdev_adjacent *adj;
5604 adj = __netdev_find_adj(adj_dev, dev_list);
5607 adj->ref_nr += ref_nr;
5611 adj = kmalloc(sizeof(*adj), GFP_KERNEL);
5616 adj->master = master;
5617 adj->ref_nr = ref_nr;
5618 adj->private = private;
5621 pr_debug("dev_hold for %s, because of link added from %s to %s\n",
5622 adj_dev->name, dev->name, adj_dev->name);
5624 if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list)) {
5625 ret = netdev_adjacent_sysfs_add(dev, adj_dev, dev_list);
5630 /* Ensure that master link is always the first item in list. */
5632 ret = sysfs_create_link(&(dev->dev.kobj),
5633 &(adj_dev->dev.kobj), "master");
5635 goto remove_symlinks;
5637 list_add_rcu(&adj->list, dev_list);
5639 list_add_tail_rcu(&adj->list, dev_list);
5645 if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list))
5646 netdev_adjacent_sysfs_del(dev, adj_dev->name, dev_list);
5654 static void __netdev_adjacent_dev_remove(struct net_device *dev,
5655 struct net_device *adj_dev,
5657 struct list_head *dev_list)
5659 struct netdev_adjacent *adj;
5661 adj = __netdev_find_adj(adj_dev, dev_list);
5664 pr_err("tried to remove device %s from %s\n",
5665 dev->name, adj_dev->name);
5669 if (adj->ref_nr > ref_nr) {
5670 pr_debug("%s to %s ref_nr-%d = %d\n", dev->name, adj_dev->name,
5671 ref_nr, adj->ref_nr-ref_nr);
5672 adj->ref_nr -= ref_nr;
5677 sysfs_remove_link(&(dev->dev.kobj), "master");
5679 if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list))
5680 netdev_adjacent_sysfs_del(dev, adj_dev->name, dev_list);
5682 list_del_rcu(&adj->list);
5683 pr_debug("dev_put for %s, because link removed from %s to %s\n",
5684 adj_dev->name, dev->name, adj_dev->name);
5686 kfree_rcu(adj, rcu);
5689 static int __netdev_adjacent_dev_link_lists(struct net_device *dev,
5690 struct net_device *upper_dev,
5692 struct list_head *up_list,
5693 struct list_head *down_list,
5694 void *private, bool master)
5698 ret = __netdev_adjacent_dev_insert(dev, upper_dev, ref_nr, up_list,
5703 ret = __netdev_adjacent_dev_insert(upper_dev, dev, ref_nr, down_list,
5706 __netdev_adjacent_dev_remove(dev, upper_dev, ref_nr, up_list);
5713 static int __netdev_adjacent_dev_link(struct net_device *dev,
5714 struct net_device *upper_dev,
5717 return __netdev_adjacent_dev_link_lists(dev, upper_dev, ref_nr,
5718 &dev->all_adj_list.upper,
5719 &upper_dev->all_adj_list.lower,
5723 static void __netdev_adjacent_dev_unlink_lists(struct net_device *dev,
5724 struct net_device *upper_dev,
5726 struct list_head *up_list,
5727 struct list_head *down_list)
5729 __netdev_adjacent_dev_remove(dev, upper_dev, ref_nr, up_list);
5730 __netdev_adjacent_dev_remove(upper_dev, dev, ref_nr, down_list);
5733 static void __netdev_adjacent_dev_unlink(struct net_device *dev,
5734 struct net_device *upper_dev,
5737 __netdev_adjacent_dev_unlink_lists(dev, upper_dev, ref_nr,
5738 &dev->all_adj_list.upper,
5739 &upper_dev->all_adj_list.lower);
5742 static int __netdev_adjacent_dev_link_neighbour(struct net_device *dev,
5743 struct net_device *upper_dev,
5744 void *private, bool master)
5746 int ret = __netdev_adjacent_dev_link(dev, upper_dev, 1);
5751 ret = __netdev_adjacent_dev_link_lists(dev, upper_dev, 1,
5752 &dev->adj_list.upper,
5753 &upper_dev->adj_list.lower,
5756 __netdev_adjacent_dev_unlink(dev, upper_dev, 1);
5763 static void __netdev_adjacent_dev_unlink_neighbour(struct net_device *dev,
5764 struct net_device *upper_dev)
5766 __netdev_adjacent_dev_unlink(dev, upper_dev, 1);
5767 __netdev_adjacent_dev_unlink_lists(dev, upper_dev, 1,
5768 &dev->adj_list.upper,
5769 &upper_dev->adj_list.lower);
5772 static int __netdev_upper_dev_link(struct net_device *dev,
5773 struct net_device *upper_dev, bool master,
5774 void *upper_priv, void *upper_info)
5776 struct netdev_notifier_changeupper_info changeupper_info;
5777 struct netdev_adjacent *i, *j, *to_i, *to_j;
5782 if (dev == upper_dev)
5785 /* To prevent loops, check if dev is not upper device to upper_dev. */
5786 if (__netdev_find_adj(dev, &upper_dev->all_adj_list.upper))
5789 if (__netdev_find_adj(upper_dev, &dev->adj_list.upper))
5792 if (master && netdev_master_upper_dev_get(dev))
5795 changeupper_info.upper_dev = upper_dev;
5796 changeupper_info.master = master;
5797 changeupper_info.linking = true;
5798 changeupper_info.upper_info = upper_info;
5800 ret = call_netdevice_notifiers_info(NETDEV_PRECHANGEUPPER, dev,
5801 &changeupper_info.info);
5802 ret = notifier_to_errno(ret);
5806 ret = __netdev_adjacent_dev_link_neighbour(dev, upper_dev, upper_priv,
5811 /* Now that we linked these devs, make all the upper_dev's
5812 * all_adj_list.upper visible to every dev's all_adj_list.lower an
5813 * versa, and don't forget the devices itself. All of these
5814 * links are non-neighbours.
5816 list_for_each_entry(i, &dev->all_adj_list.lower, list) {
5817 list_for_each_entry(j, &upper_dev->all_adj_list.upper, list) {
5818 pr_debug("Interlinking %s with %s, non-neighbour\n",
5819 i->dev->name, j->dev->name);
5820 ret = __netdev_adjacent_dev_link(i->dev, j->dev, i->ref_nr);
5826 /* add dev to every upper_dev's upper device */
5827 list_for_each_entry(i, &upper_dev->all_adj_list.upper, list) {
5828 pr_debug("linking %s's upper device %s with %s\n",
5829 upper_dev->name, i->dev->name, dev->name);
5830 ret = __netdev_adjacent_dev_link(dev, i->dev, i->ref_nr);
5832 goto rollback_upper_mesh;
5835 /* add upper_dev to every dev's lower device */
5836 list_for_each_entry(i, &dev->all_adj_list.lower, list) {
5837 pr_debug("linking %s's lower device %s with %s\n", dev->name,
5838 i->dev->name, upper_dev->name);
5839 ret = __netdev_adjacent_dev_link(i->dev, upper_dev, i->ref_nr);
5841 goto rollback_lower_mesh;
5844 ret = call_netdevice_notifiers_info(NETDEV_CHANGEUPPER, dev,
5845 &changeupper_info.info);
5846 ret = notifier_to_errno(ret);
5848 goto rollback_lower_mesh;
5852 rollback_lower_mesh:
5854 list_for_each_entry(i, &dev->all_adj_list.lower, list) {
5857 __netdev_adjacent_dev_unlink(i->dev, upper_dev, i->ref_nr);
5862 rollback_upper_mesh:
5864 list_for_each_entry(i, &upper_dev->all_adj_list.upper, list) {
5867 __netdev_adjacent_dev_unlink(dev, i->dev, i->ref_nr);
5875 list_for_each_entry(i, &dev->all_adj_list.lower, list) {
5876 list_for_each_entry(j, &upper_dev->all_adj_list.upper, list) {
5877 if (i == to_i && j == to_j)
5879 __netdev_adjacent_dev_unlink(i->dev, j->dev, i->ref_nr);
5885 __netdev_adjacent_dev_unlink_neighbour(dev, upper_dev);
5891 * netdev_upper_dev_link - Add a link to the upper device
5893 * @upper_dev: new upper device
5895 * Adds a link to device which is upper to this one. The caller must hold
5896 * the RTNL lock. On a failure a negative errno code is returned.
5897 * On success the reference counts are adjusted and the function
5900 int netdev_upper_dev_link(struct net_device *dev,
5901 struct net_device *upper_dev)
5903 return __netdev_upper_dev_link(dev, upper_dev, false, NULL, NULL);
5905 EXPORT_SYMBOL(netdev_upper_dev_link);
5908 * netdev_master_upper_dev_link - Add a master link to the upper device
5910 * @upper_dev: new upper device
5911 * @upper_priv: upper device private
5912 * @upper_info: upper info to be passed down via notifier
5914 * Adds a link to device which is upper to this one. In this case, only
5915 * one master upper device can be linked, although other non-master devices
5916 * might be linked as well. The caller must hold the RTNL lock.
5917 * On a failure a negative errno code is returned. On success the reference
5918 * counts are adjusted and the function returns zero.
5920 int netdev_master_upper_dev_link(struct net_device *dev,
5921 struct net_device *upper_dev,
5922 void *upper_priv, void *upper_info)
5924 return __netdev_upper_dev_link(dev, upper_dev, true,
5925 upper_priv, upper_info);
5927 EXPORT_SYMBOL(netdev_master_upper_dev_link);
5930 * netdev_upper_dev_unlink - Removes a link to upper device
5932 * @upper_dev: new upper device
5934 * Removes a link to device which is upper to this one. The caller must hold
5937 void netdev_upper_dev_unlink(struct net_device *dev,
5938 struct net_device *upper_dev)
5940 struct netdev_notifier_changeupper_info changeupper_info;
5941 struct netdev_adjacent *i, *j;
5944 changeupper_info.upper_dev = upper_dev;
5945 changeupper_info.master = netdev_master_upper_dev_get(dev) == upper_dev;
5946 changeupper_info.linking = false;
5948 call_netdevice_notifiers_info(NETDEV_PRECHANGEUPPER, dev,
5949 &changeupper_info.info);
5951 __netdev_adjacent_dev_unlink_neighbour(dev, upper_dev);
5953 /* Here is the tricky part. We must remove all dev's lower
5954 * devices from all upper_dev's upper devices and vice
5955 * versa, to maintain the graph relationship.
5957 list_for_each_entry(i, &dev->all_adj_list.lower, list)
5958 list_for_each_entry(j, &upper_dev->all_adj_list.upper, list)
5959 __netdev_adjacent_dev_unlink(i->dev, j->dev, i->ref_nr);
5961 /* remove also the devices itself from lower/upper device
5964 list_for_each_entry(i, &dev->all_adj_list.lower, list)
5965 __netdev_adjacent_dev_unlink(i->dev, upper_dev, i->ref_nr);
5967 list_for_each_entry(i, &upper_dev->all_adj_list.upper, list)
5968 __netdev_adjacent_dev_unlink(dev, i->dev, i->ref_nr);
5970 call_netdevice_notifiers_info(NETDEV_CHANGEUPPER, dev,
5971 &changeupper_info.info);
5973 EXPORT_SYMBOL(netdev_upper_dev_unlink);
5976 * netdev_bonding_info_change - Dispatch event about slave change
5978 * @bonding_info: info to dispatch
5980 * Send NETDEV_BONDING_INFO to netdev notifiers with info.
5981 * The caller must hold the RTNL lock.
5983 void netdev_bonding_info_change(struct net_device *dev,
5984 struct netdev_bonding_info *bonding_info)
5986 struct netdev_notifier_bonding_info info;
5988 memcpy(&info.bonding_info, bonding_info,
5989 sizeof(struct netdev_bonding_info));
5990 call_netdevice_notifiers_info(NETDEV_BONDING_INFO, dev,
5993 EXPORT_SYMBOL(netdev_bonding_info_change);
5995 static void netdev_adjacent_add_links(struct net_device *dev)
5997 struct netdev_adjacent *iter;
5999 struct net *net = dev_net(dev);
6001 list_for_each_entry(iter, &dev->adj_list.upper, list) {
6002 if (!net_eq(net, dev_net(iter->dev)))
6004 netdev_adjacent_sysfs_add(iter->dev, dev,
6005 &iter->dev->adj_list.lower);
6006 netdev_adjacent_sysfs_add(dev, iter->dev,
6007 &dev->adj_list.upper);
6010 list_for_each_entry(iter, &dev->adj_list.lower, list) {
6011 if (!net_eq(net, dev_net(iter->dev)))
6013 netdev_adjacent_sysfs_add(iter->dev, dev,
6014 &iter->dev->adj_list.upper);
6015 netdev_adjacent_sysfs_add(dev, iter->dev,
6016 &dev->adj_list.lower);
6020 static void netdev_adjacent_del_links(struct net_device *dev)
6022 struct netdev_adjacent *iter;
6024 struct net *net = dev_net(dev);
6026 list_for_each_entry(iter, &dev->adj_list.upper, list) {
6027 if (!net_eq(net, dev_net(iter->dev)))
6029 netdev_adjacent_sysfs_del(iter->dev, dev->name,
6030 &iter->dev->adj_list.lower);
6031 netdev_adjacent_sysfs_del(dev, iter->dev->name,
6032 &dev->adj_list.upper);
6035 list_for_each_entry(iter, &dev->adj_list.lower, list) {
6036 if (!net_eq(net, dev_net(iter->dev)))
6038 netdev_adjacent_sysfs_del(iter->dev, dev->name,
6039 &iter->dev->adj_list.upper);
6040 netdev_adjacent_sysfs_del(dev, iter->dev->name,
6041 &dev->adj_list.lower);
6045 void netdev_adjacent_rename_links(struct net_device *dev, char *oldname)
6047 struct netdev_adjacent *iter;
6049 struct net *net = dev_net(dev);
6051 list_for_each_entry(iter, &dev->adj_list.upper, list) {
6052 if (!net_eq(net, dev_net(iter->dev)))
6054 netdev_adjacent_sysfs_del(iter->dev, oldname,
6055 &iter->dev->adj_list.lower);
6056 netdev_adjacent_sysfs_add(iter->dev, dev,
6057 &iter->dev->adj_list.lower);
6060 list_for_each_entry(iter, &dev->adj_list.lower, list) {
6061 if (!net_eq(net, dev_net(iter->dev)))
6063 netdev_adjacent_sysfs_del(iter->dev, oldname,
6064 &iter->dev->adj_list.upper);
6065 netdev_adjacent_sysfs_add(iter->dev, dev,
6066 &iter->dev->adj_list.upper);
6070 void *netdev_lower_dev_get_private(struct net_device *dev,
6071 struct net_device *lower_dev)
6073 struct netdev_adjacent *lower;
6077 lower = __netdev_find_adj(lower_dev, &dev->adj_list.lower);
6081 return lower->private;
6083 EXPORT_SYMBOL(netdev_lower_dev_get_private);
6086 int dev_get_nest_level(struct net_device *dev)
6088 struct net_device *lower = NULL;
6089 struct list_head *iter;
6095 netdev_for_each_lower_dev(dev, lower, iter) {
6096 nest = dev_get_nest_level(lower);
6097 if (max_nest < nest)
6101 return max_nest + 1;
6103 EXPORT_SYMBOL(dev_get_nest_level);
6106 * netdev_lower_change - Dispatch event about lower device state change
6107 * @lower_dev: device
6108 * @lower_state_info: state to dispatch
6110 * Send NETDEV_CHANGELOWERSTATE to netdev notifiers with info.
6111 * The caller must hold the RTNL lock.
6113 void netdev_lower_state_changed(struct net_device *lower_dev,
6114 void *lower_state_info)
6116 struct netdev_notifier_changelowerstate_info changelowerstate_info;
6119 changelowerstate_info.lower_state_info = lower_state_info;
6120 call_netdevice_notifiers_info(NETDEV_CHANGELOWERSTATE, lower_dev,
6121 &changelowerstate_info.info);
6123 EXPORT_SYMBOL(netdev_lower_state_changed);
6125 int netdev_default_l2upper_neigh_construct(struct net_device *dev,
6126 struct neighbour *n)
6128 struct net_device *lower_dev, *stop_dev;
6129 struct list_head *iter;
6132 netdev_for_each_lower_dev(dev, lower_dev, iter) {
6133 if (!lower_dev->netdev_ops->ndo_neigh_construct)
6135 err = lower_dev->netdev_ops->ndo_neigh_construct(lower_dev, n);
6137 stop_dev = lower_dev;
6144 netdev_for_each_lower_dev(dev, lower_dev, iter) {
6145 if (lower_dev == stop_dev)
6147 if (!lower_dev->netdev_ops->ndo_neigh_destroy)
6149 lower_dev->netdev_ops->ndo_neigh_destroy(lower_dev, n);
6153 EXPORT_SYMBOL_GPL(netdev_default_l2upper_neigh_construct);
6155 void netdev_default_l2upper_neigh_destroy(struct net_device *dev,
6156 struct neighbour *n)
6158 struct net_device *lower_dev;
6159 struct list_head *iter;
6161 netdev_for_each_lower_dev(dev, lower_dev, iter) {
6162 if (!lower_dev->netdev_ops->ndo_neigh_destroy)
6164 lower_dev->netdev_ops->ndo_neigh_destroy(lower_dev, n);
6167 EXPORT_SYMBOL_GPL(netdev_default_l2upper_neigh_destroy);
6169 static void dev_change_rx_flags(struct net_device *dev, int flags)
6171 const struct net_device_ops *ops = dev->netdev_ops;
6173 if (ops->ndo_change_rx_flags)
6174 ops->ndo_change_rx_flags(dev, flags);
6177 static int __dev_set_promiscuity(struct net_device *dev, int inc, bool notify)
6179 unsigned int old_flags = dev->flags;
6185 dev->flags |= IFF_PROMISC;
6186 dev->promiscuity += inc;
6187 if (dev->promiscuity == 0) {
6190 * If inc causes overflow, untouch promisc and return error.
6193 dev->flags &= ~IFF_PROMISC;
6195 dev->promiscuity -= inc;
6196 pr_warn("%s: promiscuity touches roof, set promiscuity failed. promiscuity feature of device might be broken.\n",
6201 if (dev->flags != old_flags) {
6202 pr_info("device %s %s promiscuous mode\n",
6204 dev->flags & IFF_PROMISC ? "entered" : "left");
6205 if (audit_enabled) {
6206 current_uid_gid(&uid, &gid);
6207 audit_log(current->audit_context, GFP_ATOMIC,
6208 AUDIT_ANOM_PROMISCUOUS,
6209 "dev=%s prom=%d old_prom=%d auid=%u uid=%u gid=%u ses=%u",
6210 dev->name, (dev->flags & IFF_PROMISC),
6211 (old_flags & IFF_PROMISC),
6212 from_kuid(&init_user_ns, audit_get_loginuid(current)),
6213 from_kuid(&init_user_ns, uid),
6214 from_kgid(&init_user_ns, gid),
6215 audit_get_sessionid(current));
6218 dev_change_rx_flags(dev, IFF_PROMISC);
6221 __dev_notify_flags(dev, old_flags, IFF_PROMISC);
6226 * dev_set_promiscuity - update promiscuity count on a device
6230 * Add or remove promiscuity from a device. While the count in the device
6231 * remains above zero the interface remains promiscuous. Once it hits zero
6232 * the device reverts back to normal filtering operation. A negative inc
6233 * value is used to drop promiscuity on the device.
6234 * Return 0 if successful or a negative errno code on error.
6236 int dev_set_promiscuity(struct net_device *dev, int inc)
6238 unsigned int old_flags = dev->flags;
6241 err = __dev_set_promiscuity(dev, inc, true);
6244 if (dev->flags != old_flags)
6245 dev_set_rx_mode(dev);
6248 EXPORT_SYMBOL(dev_set_promiscuity);
6250 static int __dev_set_allmulti(struct net_device *dev, int inc, bool notify)
6252 unsigned int old_flags = dev->flags, old_gflags = dev->gflags;
6256 dev->flags |= IFF_ALLMULTI;
6257 dev->allmulti += inc;
6258 if (dev->allmulti == 0) {
6261 * If inc causes overflow, untouch allmulti and return error.
6264 dev->flags &= ~IFF_ALLMULTI;
6266 dev->allmulti -= inc;
6267 pr_warn("%s: allmulti touches roof, set allmulti failed. allmulti feature of device might be broken.\n",
6272 if (dev->flags ^ old_flags) {
6273 dev_change_rx_flags(dev, IFF_ALLMULTI);
6274 dev_set_rx_mode(dev);
6276 __dev_notify_flags(dev, old_flags,
6277 dev->gflags ^ old_gflags);
6283 * dev_set_allmulti - update allmulti count on a device
6287 * Add or remove reception of all multicast frames to a device. While the
6288 * count in the device remains above zero the interface remains listening
6289 * to all interfaces. Once it hits zero the device reverts back to normal
6290 * filtering operation. A negative @inc value is used to drop the counter
6291 * when releasing a resource needing all multicasts.
6292 * Return 0 if successful or a negative errno code on error.
6295 int dev_set_allmulti(struct net_device *dev, int inc)
6297 return __dev_set_allmulti(dev, inc, true);
6299 EXPORT_SYMBOL(dev_set_allmulti);
6302 * Upload unicast and multicast address lists to device and
6303 * configure RX filtering. When the device doesn't support unicast
6304 * filtering it is put in promiscuous mode while unicast addresses
6307 void __dev_set_rx_mode(struct net_device *dev)
6309 const struct net_device_ops *ops = dev->netdev_ops;
6311 /* dev_open will call this function so the list will stay sane. */
6312 if (!(dev->flags&IFF_UP))
6315 if (!netif_device_present(dev))
6318 if (!(dev->priv_flags & IFF_UNICAST_FLT)) {
6319 /* Unicast addresses changes may only happen under the rtnl,
6320 * therefore calling __dev_set_promiscuity here is safe.
6322 if (!netdev_uc_empty(dev) && !dev->uc_promisc) {
6323 __dev_set_promiscuity(dev, 1, false);
6324 dev->uc_promisc = true;
6325 } else if (netdev_uc_empty(dev) && dev->uc_promisc) {
6326 __dev_set_promiscuity(dev, -1, false);
6327 dev->uc_promisc = false;
6331 if (ops->ndo_set_rx_mode)
6332 ops->ndo_set_rx_mode(dev);
6335 void dev_set_rx_mode(struct net_device *dev)
6337 netif_addr_lock_bh(dev);
6338 __dev_set_rx_mode(dev);
6339 netif_addr_unlock_bh(dev);
6343 * dev_get_flags - get flags reported to userspace
6346 * Get the combination of flag bits exported through APIs to userspace.
6348 unsigned int dev_get_flags(const struct net_device *dev)
6352 flags = (dev->flags & ~(IFF_PROMISC |
6357 (dev->gflags & (IFF_PROMISC |
6360 if (netif_running(dev)) {
6361 if (netif_oper_up(dev))
6362 flags |= IFF_RUNNING;
6363 if (netif_carrier_ok(dev))
6364 flags |= IFF_LOWER_UP;
6365 if (netif_dormant(dev))
6366 flags |= IFF_DORMANT;
6371 EXPORT_SYMBOL(dev_get_flags);
6373 int __dev_change_flags(struct net_device *dev, unsigned int flags)
6375 unsigned int old_flags = dev->flags;
6381 * Set the flags on our device.
6384 dev->flags = (flags & (IFF_DEBUG | IFF_NOTRAILERS | IFF_NOARP |
6385 IFF_DYNAMIC | IFF_MULTICAST | IFF_PORTSEL |
6387 (dev->flags & (IFF_UP | IFF_VOLATILE | IFF_PROMISC |
6391 * Load in the correct multicast list now the flags have changed.
6394 if ((old_flags ^ flags) & IFF_MULTICAST)
6395 dev_change_rx_flags(dev, IFF_MULTICAST);
6397 dev_set_rx_mode(dev);
6400 * Have we downed the interface. We handle IFF_UP ourselves
6401 * according to user attempts to set it, rather than blindly
6406 if ((old_flags ^ flags) & IFF_UP)
6407 ret = ((old_flags & IFF_UP) ? __dev_close : __dev_open)(dev);
6409 if ((flags ^ dev->gflags) & IFF_PROMISC) {
6410 int inc = (flags & IFF_PROMISC) ? 1 : -1;
6411 unsigned int old_flags = dev->flags;
6413 dev->gflags ^= IFF_PROMISC;
6415 if (__dev_set_promiscuity(dev, inc, false) >= 0)
6416 if (dev->flags != old_flags)
6417 dev_set_rx_mode(dev);
6420 /* NOTE: order of synchronization of IFF_PROMISC and IFF_ALLMULTI
6421 is important. Some (broken) drivers set IFF_PROMISC, when
6422 IFF_ALLMULTI is requested not asking us and not reporting.
6424 if ((flags ^ dev->gflags) & IFF_ALLMULTI) {
6425 int inc = (flags & IFF_ALLMULTI) ? 1 : -1;
6427 dev->gflags ^= IFF_ALLMULTI;
6428 __dev_set_allmulti(dev, inc, false);
6434 void __dev_notify_flags(struct net_device *dev, unsigned int old_flags,
6435 unsigned int gchanges)
6437 unsigned int changes = dev->flags ^ old_flags;
6440 rtmsg_ifinfo(RTM_NEWLINK, dev, gchanges, GFP_ATOMIC);
6442 if (changes & IFF_UP) {
6443 if (dev->flags & IFF_UP)
6444 call_netdevice_notifiers(NETDEV_UP, dev);
6446 call_netdevice_notifiers(NETDEV_DOWN, dev);
6449 if (dev->flags & IFF_UP &&
6450 (changes & ~(IFF_UP | IFF_PROMISC | IFF_ALLMULTI | IFF_VOLATILE))) {
6451 struct netdev_notifier_change_info change_info;
6453 change_info.flags_changed = changes;
6454 call_netdevice_notifiers_info(NETDEV_CHANGE, dev,
6460 * dev_change_flags - change device settings
6462 * @flags: device state flags
6464 * Change settings on device based state flags. The flags are
6465 * in the userspace exported format.
6467 int dev_change_flags(struct net_device *dev, unsigned int flags)
6470 unsigned int changes, old_flags = dev->flags, old_gflags = dev->gflags;
6472 ret = __dev_change_flags(dev, flags);
6476 changes = (old_flags ^ dev->flags) | (old_gflags ^ dev->gflags);
6477 __dev_notify_flags(dev, old_flags, changes);
6480 EXPORT_SYMBOL(dev_change_flags);
6482 static int __dev_set_mtu(struct net_device *dev, int new_mtu)
6484 const struct net_device_ops *ops = dev->netdev_ops;
6486 if (ops->ndo_change_mtu)
6487 return ops->ndo_change_mtu(dev, new_mtu);
6494 * dev_set_mtu - Change maximum transfer unit
6496 * @new_mtu: new transfer unit
6498 * Change the maximum transfer size of the network device.
6500 int dev_set_mtu(struct net_device *dev, int new_mtu)
6504 if (new_mtu == dev->mtu)
6507 /* MTU must be positive. */
6511 if (!netif_device_present(dev))
6514 err = call_netdevice_notifiers(NETDEV_PRECHANGEMTU, dev);
6515 err = notifier_to_errno(err);
6519 orig_mtu = dev->mtu;
6520 err = __dev_set_mtu(dev, new_mtu);
6523 err = call_netdevice_notifiers(NETDEV_CHANGEMTU, dev);
6524 err = notifier_to_errno(err);
6526 /* setting mtu back and notifying everyone again,
6527 * so that they have a chance to revert changes.
6529 __dev_set_mtu(dev, orig_mtu);
6530 call_netdevice_notifiers(NETDEV_CHANGEMTU, dev);
6535 EXPORT_SYMBOL(dev_set_mtu);
6538 * dev_set_group - Change group this device belongs to
6540 * @new_group: group this device should belong to
6542 void dev_set_group(struct net_device *dev, int new_group)
6544 dev->group = new_group;
6546 EXPORT_SYMBOL(dev_set_group);
6549 * dev_set_mac_address - Change Media Access Control Address
6553 * Change the hardware (MAC) address of the device
6555 int dev_set_mac_address(struct net_device *dev, struct sockaddr *sa)
6557 const struct net_device_ops *ops = dev->netdev_ops;
6560 if (!ops->ndo_set_mac_address)
6562 if (sa->sa_family != dev->type)
6564 if (!netif_device_present(dev))
6566 err = ops->ndo_set_mac_address(dev, sa);
6569 dev->addr_assign_type = NET_ADDR_SET;
6570 call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
6571 add_device_randomness(dev->dev_addr, dev->addr_len);
6574 EXPORT_SYMBOL(dev_set_mac_address);
6577 * dev_change_carrier - Change device carrier
6579 * @new_carrier: new value
6581 * Change device carrier
6583 int dev_change_carrier(struct net_device *dev, bool new_carrier)
6585 const struct net_device_ops *ops = dev->netdev_ops;
6587 if (!ops->ndo_change_carrier)
6589 if (!netif_device_present(dev))
6591 return ops->ndo_change_carrier(dev, new_carrier);
6593 EXPORT_SYMBOL(dev_change_carrier);
6596 * dev_get_phys_port_id - Get device physical port ID
6600 * Get device physical port ID
6602 int dev_get_phys_port_id(struct net_device *dev,
6603 struct netdev_phys_item_id *ppid)
6605 const struct net_device_ops *ops = dev->netdev_ops;
6607 if (!ops->ndo_get_phys_port_id)
6609 return ops->ndo_get_phys_port_id(dev, ppid);
6611 EXPORT_SYMBOL(dev_get_phys_port_id);
6614 * dev_get_phys_port_name - Get device physical port name
6617 * @len: limit of bytes to copy to name
6619 * Get device physical port name
6621 int dev_get_phys_port_name(struct net_device *dev,
6622 char *name, size_t len)
6624 const struct net_device_ops *ops = dev->netdev_ops;
6626 if (!ops->ndo_get_phys_port_name)
6628 return ops->ndo_get_phys_port_name(dev, name, len);
6630 EXPORT_SYMBOL(dev_get_phys_port_name);
6633 * dev_change_proto_down - update protocol port state information
6635 * @proto_down: new value
6637 * This info can be used by switch drivers to set the phys state of the
6640 int dev_change_proto_down(struct net_device *dev, bool proto_down)
6642 const struct net_device_ops *ops = dev->netdev_ops;
6644 if (!ops->ndo_change_proto_down)
6646 if (!netif_device_present(dev))
6648 return ops->ndo_change_proto_down(dev, proto_down);
6650 EXPORT_SYMBOL(dev_change_proto_down);
6653 * dev_change_xdp_fd - set or clear a bpf program for a device rx path
6655 * @fd: new program fd or negative value to clear
6657 * Set or clear a bpf program for a device
6659 int dev_change_xdp_fd(struct net_device *dev, int fd)
6661 const struct net_device_ops *ops = dev->netdev_ops;
6662 struct bpf_prog *prog = NULL;
6663 struct netdev_xdp xdp = {};
6669 prog = bpf_prog_get_type(fd, BPF_PROG_TYPE_XDP);
6671 return PTR_ERR(prog);
6674 xdp.command = XDP_SETUP_PROG;
6676 err = ops->ndo_xdp(dev, &xdp);
6677 if (err < 0 && prog)
6682 EXPORT_SYMBOL(dev_change_xdp_fd);
6685 * dev_new_index - allocate an ifindex
6686 * @net: the applicable net namespace
6688 * Returns a suitable unique value for a new device interface
6689 * number. The caller must hold the rtnl semaphore or the
6690 * dev_base_lock to be sure it remains unique.
6692 static int dev_new_index(struct net *net)
6694 int ifindex = net->ifindex;
6698 if (!__dev_get_by_index(net, ifindex))
6699 return net->ifindex = ifindex;
6703 /* Delayed registration/unregisteration */
6704 static LIST_HEAD(net_todo_list);
6705 DECLARE_WAIT_QUEUE_HEAD(netdev_unregistering_wq);
6707 static void net_set_todo(struct net_device *dev)
6709 list_add_tail(&dev->todo_list, &net_todo_list);
6710 dev_net(dev)->dev_unreg_count++;
6713 static void rollback_registered_many(struct list_head *head)
6715 struct net_device *dev, *tmp;
6716 LIST_HEAD(close_head);
6718 BUG_ON(dev_boot_phase);
6721 list_for_each_entry_safe(dev, tmp, head, unreg_list) {
6722 /* Some devices call without registering
6723 * for initialization unwind. Remove those
6724 * devices and proceed with the remaining.
6726 if (dev->reg_state == NETREG_UNINITIALIZED) {
6727 pr_debug("unregister_netdevice: device %s/%p never was registered\n",
6731 list_del(&dev->unreg_list);
6734 dev->dismantle = true;
6735 BUG_ON(dev->reg_state != NETREG_REGISTERED);
6738 /* If device is running, close it first. */
6739 list_for_each_entry(dev, head, unreg_list)
6740 list_add_tail(&dev->close_list, &close_head);
6741 dev_close_many(&close_head, true);
6743 list_for_each_entry(dev, head, unreg_list) {
6744 /* And unlink it from device chain. */
6745 unlist_netdevice(dev);
6747 dev->reg_state = NETREG_UNREGISTERING;
6749 flush_all_backlogs();
6753 list_for_each_entry(dev, head, unreg_list) {
6754 struct sk_buff *skb = NULL;
6756 /* Shutdown queueing discipline. */
6760 /* Notify protocols, that we are about to destroy
6761 this device. They should clean all the things.
6763 call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
6765 if (!dev->rtnl_link_ops ||
6766 dev->rtnl_link_state == RTNL_LINK_INITIALIZED)
6767 skb = rtmsg_ifinfo_build_skb(RTM_DELLINK, dev, ~0U,
6771 * Flush the unicast and multicast chains
6776 if (dev->netdev_ops->ndo_uninit)
6777 dev->netdev_ops->ndo_uninit(dev);
6780 rtmsg_ifinfo_send(skb, dev, GFP_KERNEL);
6782 /* Notifier chain MUST detach us all upper devices. */
6783 WARN_ON(netdev_has_any_upper_dev(dev));
6785 /* Remove entries from kobject tree */
6786 netdev_unregister_kobject(dev);
6788 /* Remove XPS queueing entries */
6789 netif_reset_xps_queues_gt(dev, 0);
6795 list_for_each_entry(dev, head, unreg_list)
6799 static void rollback_registered(struct net_device *dev)
6803 list_add(&dev->unreg_list, &single);
6804 rollback_registered_many(&single);
6808 static netdev_features_t netdev_sync_upper_features(struct net_device *lower,
6809 struct net_device *upper, netdev_features_t features)
6811 netdev_features_t upper_disables = NETIF_F_UPPER_DISABLES;
6812 netdev_features_t feature;
6815 for_each_netdev_feature(&upper_disables, feature_bit) {
6816 feature = __NETIF_F_BIT(feature_bit);
6817 if (!(upper->wanted_features & feature)
6818 && (features & feature)) {
6819 netdev_dbg(lower, "Dropping feature %pNF, upper dev %s has it off.\n",
6820 &feature, upper->name);
6821 features &= ~feature;
6828 static void netdev_sync_lower_features(struct net_device *upper,
6829 struct net_device *lower, netdev_features_t features)
6831 netdev_features_t upper_disables = NETIF_F_UPPER_DISABLES;
6832 netdev_features_t feature;
6835 for_each_netdev_feature(&upper_disables, feature_bit) {
6836 feature = __NETIF_F_BIT(feature_bit);
6837 if (!(features & feature) && (lower->features & feature)) {
6838 netdev_dbg(upper, "Disabling feature %pNF on lower dev %s.\n",
6839 &feature, lower->name);
6840 lower->wanted_features &= ~feature;
6841 netdev_update_features(lower);
6843 if (unlikely(lower->features & feature))
6844 netdev_WARN(upper, "failed to disable %pNF on %s!\n",
6845 &feature, lower->name);
6850 static netdev_features_t netdev_fix_features(struct net_device *dev,
6851 netdev_features_t features)
6853 /* Fix illegal checksum combinations */
6854 if ((features & NETIF_F_HW_CSUM) &&
6855 (features & (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))) {
6856 netdev_warn(dev, "mixed HW and IP checksum settings.\n");
6857 features &= ~(NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM);
6860 /* TSO requires that SG is present as well. */
6861 if ((features & NETIF_F_ALL_TSO) && !(features & NETIF_F_SG)) {
6862 netdev_dbg(dev, "Dropping TSO features since no SG feature.\n");
6863 features &= ~NETIF_F_ALL_TSO;
6866 if ((features & NETIF_F_TSO) && !(features & NETIF_F_HW_CSUM) &&
6867 !(features & NETIF_F_IP_CSUM)) {
6868 netdev_dbg(dev, "Dropping TSO features since no CSUM feature.\n");
6869 features &= ~NETIF_F_TSO;
6870 features &= ~NETIF_F_TSO_ECN;
6873 if ((features & NETIF_F_TSO6) && !(features & NETIF_F_HW_CSUM) &&
6874 !(features & NETIF_F_IPV6_CSUM)) {
6875 netdev_dbg(dev, "Dropping TSO6 features since no CSUM feature.\n");
6876 features &= ~NETIF_F_TSO6;
6879 /* TSO with IPv4 ID mangling requires IPv4 TSO be enabled */
6880 if ((features & NETIF_F_TSO_MANGLEID) && !(features & NETIF_F_TSO))
6881 features &= ~NETIF_F_TSO_MANGLEID;
6883 /* TSO ECN requires that TSO is present as well. */
6884 if ((features & NETIF_F_ALL_TSO) == NETIF_F_TSO_ECN)
6885 features &= ~NETIF_F_TSO_ECN;
6887 /* Software GSO depends on SG. */
6888 if ((features & NETIF_F_GSO) && !(features & NETIF_F_SG)) {
6889 netdev_dbg(dev, "Dropping NETIF_F_GSO since no SG feature.\n");
6890 features &= ~NETIF_F_GSO;
6893 /* UFO needs SG and checksumming */
6894 if (features & NETIF_F_UFO) {
6895 /* maybe split UFO into V4 and V6? */
6896 if (!(features & NETIF_F_HW_CSUM) &&
6897 ((features & (NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM)) !=
6898 (NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM))) {
6900 "Dropping NETIF_F_UFO since no checksum offload features.\n");
6901 features &= ~NETIF_F_UFO;
6904 if (!(features & NETIF_F_SG)) {
6906 "Dropping NETIF_F_UFO since no NETIF_F_SG feature.\n");
6907 features &= ~NETIF_F_UFO;
6911 /* GSO partial features require GSO partial be set */
6912 if ((features & dev->gso_partial_features) &&
6913 !(features & NETIF_F_GSO_PARTIAL)) {
6915 "Dropping partially supported GSO features since no GSO partial.\n");
6916 features &= ~dev->gso_partial_features;
6919 #ifdef CONFIG_NET_RX_BUSY_POLL
6920 if (dev->netdev_ops->ndo_busy_poll)
6921 features |= NETIF_F_BUSY_POLL;
6924 features &= ~NETIF_F_BUSY_POLL;
6929 int __netdev_update_features(struct net_device *dev)
6931 struct net_device *upper, *lower;
6932 netdev_features_t features;
6933 struct list_head *iter;
6938 features = netdev_get_wanted_features(dev);
6940 if (dev->netdev_ops->ndo_fix_features)
6941 features = dev->netdev_ops->ndo_fix_features(dev, features);
6943 /* driver might be less strict about feature dependencies */
6944 features = netdev_fix_features(dev, features);
6946 /* some features can't be enabled if they're off an an upper device */
6947 netdev_for_each_upper_dev_rcu(dev, upper, iter)
6948 features = netdev_sync_upper_features(dev, upper, features);
6950 if (dev->features == features)
6953 netdev_dbg(dev, "Features changed: %pNF -> %pNF\n",
6954 &dev->features, &features);
6956 if (dev->netdev_ops->ndo_set_features)
6957 err = dev->netdev_ops->ndo_set_features(dev, features);
6961 if (unlikely(err < 0)) {
6963 "set_features() failed (%d); wanted %pNF, left %pNF\n",
6964 err, &features, &dev->features);
6965 /* return non-0 since some features might have changed and
6966 * it's better to fire a spurious notification than miss it
6972 /* some features must be disabled on lower devices when disabled
6973 * on an upper device (think: bonding master or bridge)
6975 netdev_for_each_lower_dev(dev, lower, iter)
6976 netdev_sync_lower_features(dev, lower, features);
6979 dev->features = features;
6981 return err < 0 ? 0 : 1;
6985 * netdev_update_features - recalculate device features
6986 * @dev: the device to check
6988 * Recalculate dev->features set and send notifications if it
6989 * has changed. Should be called after driver or hardware dependent
6990 * conditions might have changed that influence the features.
6992 void netdev_update_features(struct net_device *dev)
6994 if (__netdev_update_features(dev))
6995 netdev_features_change(dev);
6997 EXPORT_SYMBOL(netdev_update_features);
7000 * netdev_change_features - recalculate device features
7001 * @dev: the device to check
7003 * Recalculate dev->features set and send notifications even
7004 * if they have not changed. Should be called instead of
7005 * netdev_update_features() if also dev->vlan_features might
7006 * have changed to allow the changes to be propagated to stacked
7009 void netdev_change_features(struct net_device *dev)
7011 __netdev_update_features(dev);
7012 netdev_features_change(dev);
7014 EXPORT_SYMBOL(netdev_change_features);
7017 * netif_stacked_transfer_operstate - transfer operstate
7018 * @rootdev: the root or lower level device to transfer state from
7019 * @dev: the device to transfer operstate to
7021 * Transfer operational state from root to device. This is normally
7022 * called when a stacking relationship exists between the root
7023 * device and the device(a leaf device).
7025 void netif_stacked_transfer_operstate(const struct net_device *rootdev,
7026 struct net_device *dev)
7028 if (rootdev->operstate == IF_OPER_DORMANT)
7029 netif_dormant_on(dev);
7031 netif_dormant_off(dev);
7033 if (netif_carrier_ok(rootdev)) {
7034 if (!netif_carrier_ok(dev))
7035 netif_carrier_on(dev);
7037 if (netif_carrier_ok(dev))
7038 netif_carrier_off(dev);
7041 EXPORT_SYMBOL(netif_stacked_transfer_operstate);
7044 static int netif_alloc_rx_queues(struct net_device *dev)
7046 unsigned int i, count = dev->num_rx_queues;
7047 struct netdev_rx_queue *rx;
7048 size_t sz = count * sizeof(*rx);
7052 rx = kzalloc(sz, GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT);
7060 for (i = 0; i < count; i++)
7066 static void netdev_init_one_queue(struct net_device *dev,
7067 struct netdev_queue *queue, void *_unused)
7069 /* Initialize queue lock */
7070 spin_lock_init(&queue->_xmit_lock);
7071 netdev_set_xmit_lockdep_class(&queue->_xmit_lock, dev->type);
7072 queue->xmit_lock_owner = -1;
7073 netdev_queue_numa_node_write(queue, NUMA_NO_NODE);
7076 dql_init(&queue->dql, HZ);
7080 static void netif_free_tx_queues(struct net_device *dev)
7085 static int netif_alloc_netdev_queues(struct net_device *dev)
7087 unsigned int count = dev->num_tx_queues;
7088 struct netdev_queue *tx;
7089 size_t sz = count * sizeof(*tx);
7091 if (count < 1 || count > 0xffff)
7094 tx = kzalloc(sz, GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT);
7102 netdev_for_each_tx_queue(dev, netdev_init_one_queue, NULL);
7103 spin_lock_init(&dev->tx_global_lock);
7108 void netif_tx_stop_all_queues(struct net_device *dev)
7112 for (i = 0; i < dev->num_tx_queues; i++) {
7113 struct netdev_queue *txq = netdev_get_tx_queue(dev, i);
7114 netif_tx_stop_queue(txq);
7117 EXPORT_SYMBOL(netif_tx_stop_all_queues);
7120 * register_netdevice - register a network device
7121 * @dev: device to register
7123 * Take a completed network device structure and add it to the kernel
7124 * interfaces. A %NETDEV_REGISTER message is sent to the netdev notifier
7125 * chain. 0 is returned on success. A negative errno code is returned
7126 * on a failure to set up the device, or if the name is a duplicate.
7128 * Callers must hold the rtnl semaphore. You may want
7129 * register_netdev() instead of this.
7132 * The locking appears insufficient to guarantee two parallel registers
7133 * will not get the same name.
7136 int register_netdevice(struct net_device *dev)
7139 struct net *net = dev_net(dev);
7141 BUG_ON(dev_boot_phase);
7146 /* When net_device's are persistent, this will be fatal. */
7147 BUG_ON(dev->reg_state != NETREG_UNINITIALIZED);
7150 spin_lock_init(&dev->addr_list_lock);
7151 netdev_set_addr_lockdep_class(dev);
7153 ret = dev_get_valid_name(net, dev, dev->name);
7157 /* Init, if this function is available */
7158 if (dev->netdev_ops->ndo_init) {
7159 ret = dev->netdev_ops->ndo_init(dev);
7167 if (((dev->hw_features | dev->features) &
7168 NETIF_F_HW_VLAN_CTAG_FILTER) &&
7169 (!dev->netdev_ops->ndo_vlan_rx_add_vid ||
7170 !dev->netdev_ops->ndo_vlan_rx_kill_vid)) {
7171 netdev_WARN(dev, "Buggy VLAN acceleration in driver!\n");
7178 dev->ifindex = dev_new_index(net);
7179 else if (__dev_get_by_index(net, dev->ifindex))
7182 /* Transfer changeable features to wanted_features and enable
7183 * software offloads (GSO and GRO).
7185 dev->hw_features |= NETIF_F_SOFT_FEATURES;
7186 dev->features |= NETIF_F_SOFT_FEATURES;
7187 dev->wanted_features = dev->features & dev->hw_features;
7189 if (!(dev->flags & IFF_LOOPBACK))
7190 dev->hw_features |= NETIF_F_NOCACHE_COPY;
7192 /* If IPv4 TCP segmentation offload is supported we should also
7193 * allow the device to enable segmenting the frame with the option
7194 * of ignoring a static IP ID value. This doesn't enable the
7195 * feature itself but allows the user to enable it later.
7197 if (dev->hw_features & NETIF_F_TSO)
7198 dev->hw_features |= NETIF_F_TSO_MANGLEID;
7199 if (dev->vlan_features & NETIF_F_TSO)
7200 dev->vlan_features |= NETIF_F_TSO_MANGLEID;
7201 if (dev->mpls_features & NETIF_F_TSO)
7202 dev->mpls_features |= NETIF_F_TSO_MANGLEID;
7203 if (dev->hw_enc_features & NETIF_F_TSO)
7204 dev->hw_enc_features |= NETIF_F_TSO_MANGLEID;
7206 /* Make NETIF_F_HIGHDMA inheritable to VLAN devices.
7208 dev->vlan_features |= NETIF_F_HIGHDMA;
7210 /* Make NETIF_F_SG inheritable to tunnel devices.
7212 dev->hw_enc_features |= NETIF_F_SG | NETIF_F_GSO_PARTIAL;
7214 /* Make NETIF_F_SG inheritable to MPLS.
7216 dev->mpls_features |= NETIF_F_SG;
7218 ret = call_netdevice_notifiers(NETDEV_POST_INIT, dev);
7219 ret = notifier_to_errno(ret);
7223 ret = netdev_register_kobject(dev);
7226 dev->reg_state = NETREG_REGISTERED;
7228 __netdev_update_features(dev);
7231 * Default initial state at registry is that the
7232 * device is present.
7235 set_bit(__LINK_STATE_PRESENT, &dev->state);
7237 linkwatch_init_dev(dev);
7239 dev_init_scheduler(dev);
7241 list_netdevice(dev);
7242 add_device_randomness(dev->dev_addr, dev->addr_len);
7244 /* If the device has permanent device address, driver should
7245 * set dev_addr and also addr_assign_type should be set to
7246 * NET_ADDR_PERM (default value).
7248 if (dev->addr_assign_type == NET_ADDR_PERM)
7249 memcpy(dev->perm_addr, dev->dev_addr, dev->addr_len);
7251 /* Notify protocols, that a new device appeared. */
7252 ret = call_netdevice_notifiers(NETDEV_REGISTER, dev);
7253 ret = notifier_to_errno(ret);
7255 rollback_registered(dev);
7256 dev->reg_state = NETREG_UNREGISTERED;
7259 * Prevent userspace races by waiting until the network
7260 * device is fully setup before sending notifications.
7262 if (!dev->rtnl_link_ops ||
7263 dev->rtnl_link_state == RTNL_LINK_INITIALIZED)
7264 rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U, GFP_KERNEL);
7270 if (dev->netdev_ops->ndo_uninit)
7271 dev->netdev_ops->ndo_uninit(dev);
7274 EXPORT_SYMBOL(register_netdevice);
7277 * init_dummy_netdev - init a dummy network device for NAPI
7278 * @dev: device to init
7280 * This takes a network device structure and initialize the minimum
7281 * amount of fields so it can be used to schedule NAPI polls without
7282 * registering a full blown interface. This is to be used by drivers
7283 * that need to tie several hardware interfaces to a single NAPI
7284 * poll scheduler due to HW limitations.
7286 int init_dummy_netdev(struct net_device *dev)
7288 /* Clear everything. Note we don't initialize spinlocks
7289 * are they aren't supposed to be taken by any of the
7290 * NAPI code and this dummy netdev is supposed to be
7291 * only ever used for NAPI polls
7293 memset(dev, 0, sizeof(struct net_device));
7295 /* make sure we BUG if trying to hit standard
7296 * register/unregister code path
7298 dev->reg_state = NETREG_DUMMY;
7300 /* NAPI wants this */
7301 INIT_LIST_HEAD(&dev->napi_list);
7303 /* a dummy interface is started by default */
7304 set_bit(__LINK_STATE_PRESENT, &dev->state);
7305 set_bit(__LINK_STATE_START, &dev->state);
7307 /* Note : We dont allocate pcpu_refcnt for dummy devices,
7308 * because users of this 'device' dont need to change
7314 EXPORT_SYMBOL_GPL(init_dummy_netdev);
7318 * register_netdev - register a network device
7319 * @dev: device to register
7321 * Take a completed network device structure and add it to the kernel
7322 * interfaces. A %NETDEV_REGISTER message is sent to the netdev notifier
7323 * chain. 0 is returned on success. A negative errno code is returned
7324 * on a failure to set up the device, or if the name is a duplicate.
7326 * This is a wrapper around register_netdevice that takes the rtnl semaphore
7327 * and expands the device name if you passed a format string to
7330 int register_netdev(struct net_device *dev)
7335 err = register_netdevice(dev);
7339 EXPORT_SYMBOL(register_netdev);
7341 int netdev_refcnt_read(const struct net_device *dev)
7345 for_each_possible_cpu(i)
7346 refcnt += *per_cpu_ptr(dev->pcpu_refcnt, i);
7349 EXPORT_SYMBOL(netdev_refcnt_read);
7352 * netdev_wait_allrefs - wait until all references are gone.
7353 * @dev: target net_device
7355 * This is called when unregistering network devices.
7357 * Any protocol or device that holds a reference should register
7358 * for netdevice notification, and cleanup and put back the
7359 * reference if they receive an UNREGISTER event.
7360 * We can get stuck here if buggy protocols don't correctly
7363 static void netdev_wait_allrefs(struct net_device *dev)
7365 unsigned long rebroadcast_time, warning_time;
7368 linkwatch_forget_dev(dev);
7370 rebroadcast_time = warning_time = jiffies;
7371 refcnt = netdev_refcnt_read(dev);
7373 while (refcnt != 0) {
7374 if (time_after(jiffies, rebroadcast_time + 1 * HZ)) {
7377 /* Rebroadcast unregister notification */
7378 call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
7384 call_netdevice_notifiers(NETDEV_UNREGISTER_FINAL, dev);
7385 if (test_bit(__LINK_STATE_LINKWATCH_PENDING,
7387 /* We must not have linkwatch events
7388 * pending on unregister. If this
7389 * happens, we simply run the queue
7390 * unscheduled, resulting in a noop
7393 linkwatch_run_queue();
7398 rebroadcast_time = jiffies;
7403 refcnt = netdev_refcnt_read(dev);
7405 if (time_after(jiffies, warning_time + 10 * HZ)) {
7406 pr_emerg("unregister_netdevice: waiting for %s to become free. Usage count = %d\n",
7408 warning_time = jiffies;
7417 * register_netdevice(x1);
7418 * register_netdevice(x2);
7420 * unregister_netdevice(y1);
7421 * unregister_netdevice(y2);
7427 * We are invoked by rtnl_unlock().
7428 * This allows us to deal with problems:
7429 * 1) We can delete sysfs objects which invoke hotplug
7430 * without deadlocking with linkwatch via keventd.
7431 * 2) Since we run with the RTNL semaphore not held, we can sleep
7432 * safely in order to wait for the netdev refcnt to drop to zero.
7434 * We must not return until all unregister events added during
7435 * the interval the lock was held have been completed.
7437 void netdev_run_todo(void)
7439 struct list_head list;
7441 /* Snapshot list, allow later requests */
7442 list_replace_init(&net_todo_list, &list);
7447 /* Wait for rcu callbacks to finish before next phase */
7448 if (!list_empty(&list))
7451 while (!list_empty(&list)) {
7452 struct net_device *dev
7453 = list_first_entry(&list, struct net_device, todo_list);
7454 list_del(&dev->todo_list);
7457 call_netdevice_notifiers(NETDEV_UNREGISTER_FINAL, dev);
7460 if (unlikely(dev->reg_state != NETREG_UNREGISTERING)) {
7461 pr_err("network todo '%s' but state %d\n",
7462 dev->name, dev->reg_state);
7467 dev->reg_state = NETREG_UNREGISTERED;
7469 netdev_wait_allrefs(dev);
7472 BUG_ON(netdev_refcnt_read(dev));
7473 BUG_ON(!list_empty(&dev->ptype_all));
7474 BUG_ON(!list_empty(&dev->ptype_specific));
7475 WARN_ON(rcu_access_pointer(dev->ip_ptr));
7476 WARN_ON(rcu_access_pointer(dev->ip6_ptr));
7477 WARN_ON(dev->dn_ptr);
7479 if (dev->destructor)
7480 dev->destructor(dev);
7482 /* Report a network device has been unregistered */
7484 dev_net(dev)->dev_unreg_count--;
7486 wake_up(&netdev_unregistering_wq);
7488 /* Free network device */
7489 kobject_put(&dev->dev.kobj);
7493 /* Convert net_device_stats to rtnl_link_stats64. rtnl_link_stats64 has
7494 * all the same fields in the same order as net_device_stats, with only
7495 * the type differing, but rtnl_link_stats64 may have additional fields
7496 * at the end for newer counters.
7498 void netdev_stats_to_stats64(struct rtnl_link_stats64 *stats64,
7499 const struct net_device_stats *netdev_stats)
7501 #if BITS_PER_LONG == 64
7502 BUILD_BUG_ON(sizeof(*stats64) < sizeof(*netdev_stats));
7503 memcpy(stats64, netdev_stats, sizeof(*stats64));
7504 /* zero out counters that only exist in rtnl_link_stats64 */
7505 memset((char *)stats64 + sizeof(*netdev_stats), 0,
7506 sizeof(*stats64) - sizeof(*netdev_stats));
7508 size_t i, n = sizeof(*netdev_stats) / sizeof(unsigned long);
7509 const unsigned long *src = (const unsigned long *)netdev_stats;
7510 u64 *dst = (u64 *)stats64;
7512 BUILD_BUG_ON(n > sizeof(*stats64) / sizeof(u64));
7513 for (i = 0; i < n; i++)
7515 /* zero out counters that only exist in rtnl_link_stats64 */
7516 memset((char *)stats64 + n * sizeof(u64), 0,
7517 sizeof(*stats64) - n * sizeof(u64));
7520 EXPORT_SYMBOL(netdev_stats_to_stats64);
7523 * dev_get_stats - get network device statistics
7524 * @dev: device to get statistics from
7525 * @storage: place to store stats
7527 * Get network statistics from device. Return @storage.
7528 * The device driver may provide its own method by setting
7529 * dev->netdev_ops->get_stats64 or dev->netdev_ops->get_stats;
7530 * otherwise the internal statistics structure is used.
7532 struct rtnl_link_stats64 *dev_get_stats(struct net_device *dev,
7533 struct rtnl_link_stats64 *storage)
7535 const struct net_device_ops *ops = dev->netdev_ops;
7537 if (ops->ndo_get_stats64) {
7538 memset(storage, 0, sizeof(*storage));
7539 ops->ndo_get_stats64(dev, storage);
7540 } else if (ops->ndo_get_stats) {
7541 netdev_stats_to_stats64(storage, ops->ndo_get_stats(dev));
7543 netdev_stats_to_stats64(storage, &dev->stats);
7545 storage->rx_dropped += atomic_long_read(&dev->rx_dropped);
7546 storage->tx_dropped += atomic_long_read(&dev->tx_dropped);
7547 storage->rx_nohandler += atomic_long_read(&dev->rx_nohandler);
7550 EXPORT_SYMBOL(dev_get_stats);
7552 struct netdev_queue *dev_ingress_queue_create(struct net_device *dev)
7554 struct netdev_queue *queue = dev_ingress_queue(dev);
7556 #ifdef CONFIG_NET_CLS_ACT
7559 queue = kzalloc(sizeof(*queue), GFP_KERNEL);
7562 netdev_init_one_queue(dev, queue, NULL);
7563 RCU_INIT_POINTER(queue->qdisc, &noop_qdisc);
7564 queue->qdisc_sleeping = &noop_qdisc;
7565 rcu_assign_pointer(dev->ingress_queue, queue);
7570 static const struct ethtool_ops default_ethtool_ops;
7572 void netdev_set_default_ethtool_ops(struct net_device *dev,
7573 const struct ethtool_ops *ops)
7575 if (dev->ethtool_ops == &default_ethtool_ops)
7576 dev->ethtool_ops = ops;
7578 EXPORT_SYMBOL_GPL(netdev_set_default_ethtool_ops);
7580 void netdev_freemem(struct net_device *dev)
7582 char *addr = (char *)dev - dev->padded;
7588 * alloc_netdev_mqs - allocate network device
7589 * @sizeof_priv: size of private data to allocate space for
7590 * @name: device name format string
7591 * @name_assign_type: origin of device name
7592 * @setup: callback to initialize device
7593 * @txqs: the number of TX subqueues to allocate
7594 * @rxqs: the number of RX subqueues to allocate
7596 * Allocates a struct net_device with private data area for driver use
7597 * and performs basic initialization. Also allocates subqueue structs
7598 * for each queue on the device.
7600 struct net_device *alloc_netdev_mqs(int sizeof_priv, const char *name,
7601 unsigned char name_assign_type,
7602 void (*setup)(struct net_device *),
7603 unsigned int txqs, unsigned int rxqs)
7605 struct net_device *dev;
7607 struct net_device *p;
7609 BUG_ON(strlen(name) >= sizeof(dev->name));
7612 pr_err("alloc_netdev: Unable to allocate device with zero queues\n");
7618 pr_err("alloc_netdev: Unable to allocate device with zero RX queues\n");
7623 alloc_size = sizeof(struct net_device);
7625 /* ensure 32-byte alignment of private area */
7626 alloc_size = ALIGN(alloc_size, NETDEV_ALIGN);
7627 alloc_size += sizeof_priv;
7629 /* ensure 32-byte alignment of whole construct */
7630 alloc_size += NETDEV_ALIGN - 1;
7632 p = kzalloc(alloc_size, GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT);
7634 p = vzalloc(alloc_size);
7638 dev = PTR_ALIGN(p, NETDEV_ALIGN);
7639 dev->padded = (char *)dev - (char *)p;
7641 dev->pcpu_refcnt = alloc_percpu(int);
7642 if (!dev->pcpu_refcnt)
7645 if (dev_addr_init(dev))
7651 dev_net_set(dev, &init_net);
7653 dev->gso_max_size = GSO_MAX_SIZE;
7654 dev->gso_max_segs = GSO_MAX_SEGS;
7656 INIT_LIST_HEAD(&dev->napi_list);
7657 INIT_LIST_HEAD(&dev->unreg_list);
7658 INIT_LIST_HEAD(&dev->close_list);
7659 INIT_LIST_HEAD(&dev->link_watch_list);
7660 INIT_LIST_HEAD(&dev->adj_list.upper);
7661 INIT_LIST_HEAD(&dev->adj_list.lower);
7662 INIT_LIST_HEAD(&dev->all_adj_list.upper);
7663 INIT_LIST_HEAD(&dev->all_adj_list.lower);
7664 INIT_LIST_HEAD(&dev->ptype_all);
7665 INIT_LIST_HEAD(&dev->ptype_specific);
7666 #ifdef CONFIG_NET_SCHED
7667 hash_init(dev->qdisc_hash);
7669 dev->priv_flags = IFF_XMIT_DST_RELEASE | IFF_XMIT_DST_RELEASE_PERM;
7672 if (!dev->tx_queue_len) {
7673 dev->priv_flags |= IFF_NO_QUEUE;
7674 dev->tx_queue_len = 1;
7677 dev->num_tx_queues = txqs;
7678 dev->real_num_tx_queues = txqs;
7679 if (netif_alloc_netdev_queues(dev))
7683 dev->num_rx_queues = rxqs;
7684 dev->real_num_rx_queues = rxqs;
7685 if (netif_alloc_rx_queues(dev))
7689 strcpy(dev->name, name);
7690 dev->name_assign_type = name_assign_type;
7691 dev->group = INIT_NETDEV_GROUP;
7692 if (!dev->ethtool_ops)
7693 dev->ethtool_ops = &default_ethtool_ops;
7695 nf_hook_ingress_init(dev);
7704 free_percpu(dev->pcpu_refcnt);
7706 netdev_freemem(dev);
7709 EXPORT_SYMBOL(alloc_netdev_mqs);
7712 * free_netdev - free network device
7715 * This function does the last stage of destroying an allocated device
7716 * interface. The reference to the device object is released.
7717 * If this is the last reference then it will be freed.
7718 * Must be called in process context.
7720 void free_netdev(struct net_device *dev)
7722 struct napi_struct *p, *n;
7725 netif_free_tx_queues(dev);
7730 kfree(rcu_dereference_protected(dev->ingress_queue, 1));
7732 /* Flush device addresses */
7733 dev_addr_flush(dev);
7735 list_for_each_entry_safe(p, n, &dev->napi_list, dev_list)
7738 free_percpu(dev->pcpu_refcnt);
7739 dev->pcpu_refcnt = NULL;
7741 /* Compatibility with error handling in drivers */
7742 if (dev->reg_state == NETREG_UNINITIALIZED) {
7743 netdev_freemem(dev);
7747 BUG_ON(dev->reg_state != NETREG_UNREGISTERED);
7748 dev->reg_state = NETREG_RELEASED;
7750 /* will free via device release */
7751 put_device(&dev->dev);
7753 EXPORT_SYMBOL(free_netdev);
7756 * synchronize_net - Synchronize with packet receive processing
7758 * Wait for packets currently being received to be done.
7759 * Does not block later packets from starting.
7761 void synchronize_net(void)
7764 if (rtnl_is_locked())
7765 synchronize_rcu_expedited();
7769 EXPORT_SYMBOL(synchronize_net);
7772 * unregister_netdevice_queue - remove device from the kernel
7776 * This function shuts down a device interface and removes it
7777 * from the kernel tables.
7778 * If head not NULL, device is queued to be unregistered later.
7780 * Callers must hold the rtnl semaphore. You may want
7781 * unregister_netdev() instead of this.
7784 void unregister_netdevice_queue(struct net_device *dev, struct list_head *head)
7789 list_move_tail(&dev->unreg_list, head);
7791 rollback_registered(dev);
7792 /* Finish processing unregister after unlock */
7796 EXPORT_SYMBOL(unregister_netdevice_queue);
7799 * unregister_netdevice_many - unregister many devices
7800 * @head: list of devices
7802 * Note: As most callers use a stack allocated list_head,
7803 * we force a list_del() to make sure stack wont be corrupted later.
7805 void unregister_netdevice_many(struct list_head *head)
7807 struct net_device *dev;
7809 if (!list_empty(head)) {
7810 rollback_registered_many(head);
7811 list_for_each_entry(dev, head, unreg_list)
7816 EXPORT_SYMBOL(unregister_netdevice_many);
7819 * unregister_netdev - remove device from the kernel
7822 * This function shuts down a device interface and removes it
7823 * from the kernel tables.
7825 * This is just a wrapper for unregister_netdevice that takes
7826 * the rtnl semaphore. In general you want to use this and not
7827 * unregister_netdevice.
7829 void unregister_netdev(struct net_device *dev)
7832 unregister_netdevice(dev);
7835 EXPORT_SYMBOL(unregister_netdev);
7838 * dev_change_net_namespace - move device to different nethost namespace
7840 * @net: network namespace
7841 * @pat: If not NULL name pattern to try if the current device name
7842 * is already taken in the destination network namespace.
7844 * This function shuts down a device interface and moves it
7845 * to a new network namespace. On success 0 is returned, on
7846 * a failure a netagive errno code is returned.
7848 * Callers must hold the rtnl semaphore.
7851 int dev_change_net_namespace(struct net_device *dev, struct net *net, const char *pat)
7857 /* Don't allow namespace local devices to be moved. */
7859 if (dev->features & NETIF_F_NETNS_LOCAL)
7862 /* Ensure the device has been registrered */
7863 if (dev->reg_state != NETREG_REGISTERED)
7866 /* Get out if there is nothing todo */
7868 if (net_eq(dev_net(dev), net))
7871 /* Pick the destination device name, and ensure
7872 * we can use it in the destination network namespace.
7875 if (__dev_get_by_name(net, dev->name)) {
7876 /* We get here if we can't use the current device name */
7879 if (dev_get_valid_name(net, dev, pat) < 0)
7884 * And now a mini version of register_netdevice unregister_netdevice.
7887 /* If device is running close it first. */
7890 /* And unlink it from device chain */
7892 unlist_netdevice(dev);
7896 /* Shutdown queueing discipline. */
7899 /* Notify protocols, that we are about to destroy
7900 this device. They should clean all the things.
7902 Note that dev->reg_state stays at NETREG_REGISTERED.
7903 This is wanted because this way 8021q and macvlan know
7904 the device is just moving and can keep their slaves up.
7906 call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
7908 call_netdevice_notifiers(NETDEV_UNREGISTER_FINAL, dev);
7909 rtmsg_ifinfo(RTM_DELLINK, dev, ~0U, GFP_KERNEL);
7912 * Flush the unicast and multicast chains
7917 /* Send a netdev-removed uevent to the old namespace */
7918 kobject_uevent(&dev->dev.kobj, KOBJ_REMOVE);
7919 netdev_adjacent_del_links(dev);
7921 /* Actually switch the network namespace */
7922 dev_net_set(dev, net);
7924 /* If there is an ifindex conflict assign a new one */
7925 if (__dev_get_by_index(net, dev->ifindex))
7926 dev->ifindex = dev_new_index(net);
7928 /* Send a netdev-add uevent to the new namespace */
7929 kobject_uevent(&dev->dev.kobj, KOBJ_ADD);
7930 netdev_adjacent_add_links(dev);
7932 /* Fixup kobjects */
7933 err = device_rename(&dev->dev, dev->name);
7936 /* Add the device back in the hashes */
7937 list_netdevice(dev);
7939 /* Notify protocols, that a new device appeared. */
7940 call_netdevice_notifiers(NETDEV_REGISTER, dev);
7943 * Prevent userspace races by waiting until the network
7944 * device is fully setup before sending notifications.
7946 rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U, GFP_KERNEL);
7953 EXPORT_SYMBOL_GPL(dev_change_net_namespace);
7955 static int dev_cpu_callback(struct notifier_block *nfb,
7956 unsigned long action,
7959 struct sk_buff **list_skb;
7960 struct sk_buff *skb;
7961 unsigned int cpu, oldcpu = (unsigned long)ocpu;
7962 struct softnet_data *sd, *oldsd;
7964 if (action != CPU_DEAD && action != CPU_DEAD_FROZEN)
7967 local_irq_disable();
7968 cpu = smp_processor_id();
7969 sd = &per_cpu(softnet_data, cpu);
7970 oldsd = &per_cpu(softnet_data, oldcpu);
7972 /* Find end of our completion_queue. */
7973 list_skb = &sd->completion_queue;
7975 list_skb = &(*list_skb)->next;
7976 /* Append completion queue from offline CPU. */
7977 *list_skb = oldsd->completion_queue;
7978 oldsd->completion_queue = NULL;
7980 /* Append output queue from offline CPU. */
7981 if (oldsd->output_queue) {
7982 *sd->output_queue_tailp = oldsd->output_queue;
7983 sd->output_queue_tailp = oldsd->output_queue_tailp;
7984 oldsd->output_queue = NULL;
7985 oldsd->output_queue_tailp = &oldsd->output_queue;
7987 /* Append NAPI poll list from offline CPU, with one exception :
7988 * process_backlog() must be called by cpu owning percpu backlog.
7989 * We properly handle process_queue & input_pkt_queue later.
7991 while (!list_empty(&oldsd->poll_list)) {
7992 struct napi_struct *napi = list_first_entry(&oldsd->poll_list,
7996 list_del_init(&napi->poll_list);
7997 if (napi->poll == process_backlog)
8000 ____napi_schedule(sd, napi);
8003 raise_softirq_irqoff(NET_TX_SOFTIRQ);
8006 /* Process offline CPU's input_pkt_queue */
8007 while ((skb = __skb_dequeue(&oldsd->process_queue))) {
8009 input_queue_head_incr(oldsd);
8011 while ((skb = skb_dequeue(&oldsd->input_pkt_queue))) {
8013 input_queue_head_incr(oldsd);
8021 * netdev_increment_features - increment feature set by one
8022 * @all: current feature set
8023 * @one: new feature set
8024 * @mask: mask feature set
8026 * Computes a new feature set after adding a device with feature set
8027 * @one to the master device with current feature set @all. Will not
8028 * enable anything that is off in @mask. Returns the new feature set.
8030 netdev_features_t netdev_increment_features(netdev_features_t all,
8031 netdev_features_t one, netdev_features_t mask)
8033 if (mask & NETIF_F_HW_CSUM)
8034 mask |= NETIF_F_CSUM_MASK;
8035 mask |= NETIF_F_VLAN_CHALLENGED;
8037 all |= one & (NETIF_F_ONE_FOR_ALL | NETIF_F_CSUM_MASK) & mask;
8038 all &= one | ~NETIF_F_ALL_FOR_ALL;
8040 /* If one device supports hw checksumming, set for all. */
8041 if (all & NETIF_F_HW_CSUM)
8042 all &= ~(NETIF_F_CSUM_MASK & ~NETIF_F_HW_CSUM);
8046 EXPORT_SYMBOL(netdev_increment_features);
8048 static struct hlist_head * __net_init netdev_create_hash(void)
8051 struct hlist_head *hash;
8053 hash = kmalloc(sizeof(*hash) * NETDEV_HASHENTRIES, GFP_KERNEL);
8055 for (i = 0; i < NETDEV_HASHENTRIES; i++)
8056 INIT_HLIST_HEAD(&hash[i]);
8061 /* Initialize per network namespace state */
8062 static int __net_init netdev_init(struct net *net)
8064 if (net != &init_net)
8065 INIT_LIST_HEAD(&net->dev_base_head);
8067 net->dev_name_head = netdev_create_hash();
8068 if (net->dev_name_head == NULL)
8071 net->dev_index_head = netdev_create_hash();
8072 if (net->dev_index_head == NULL)
8078 kfree(net->dev_name_head);
8084 * netdev_drivername - network driver for the device
8085 * @dev: network device
8087 * Determine network driver for device.
8089 const char *netdev_drivername(const struct net_device *dev)
8091 const struct device_driver *driver;
8092 const struct device *parent;
8093 const char *empty = "";
8095 parent = dev->dev.parent;
8099 driver = parent->driver;
8100 if (driver && driver->name)
8101 return driver->name;
8105 static void __netdev_printk(const char *level, const struct net_device *dev,
8106 struct va_format *vaf)
8108 if (dev && dev->dev.parent) {
8109 dev_printk_emit(level[1] - '0',
8112 dev_driver_string(dev->dev.parent),
8113 dev_name(dev->dev.parent),
8114 netdev_name(dev), netdev_reg_state(dev),
8117 printk("%s%s%s: %pV",
8118 level, netdev_name(dev), netdev_reg_state(dev), vaf);
8120 printk("%s(NULL net_device): %pV", level, vaf);
8124 void netdev_printk(const char *level, const struct net_device *dev,
8125 const char *format, ...)
8127 struct va_format vaf;
8130 va_start(args, format);
8135 __netdev_printk(level, dev, &vaf);
8139 EXPORT_SYMBOL(netdev_printk);
8141 #define define_netdev_printk_level(func, level) \
8142 void func(const struct net_device *dev, const char *fmt, ...) \
8144 struct va_format vaf; \
8147 va_start(args, fmt); \
8152 __netdev_printk(level, dev, &vaf); \
8156 EXPORT_SYMBOL(func);
8158 define_netdev_printk_level(netdev_emerg, KERN_EMERG);
8159 define_netdev_printk_level(netdev_alert, KERN_ALERT);
8160 define_netdev_printk_level(netdev_crit, KERN_CRIT);
8161 define_netdev_printk_level(netdev_err, KERN_ERR);
8162 define_netdev_printk_level(netdev_warn, KERN_WARNING);
8163 define_netdev_printk_level(netdev_notice, KERN_NOTICE);
8164 define_netdev_printk_level(netdev_info, KERN_INFO);
8166 static void __net_exit netdev_exit(struct net *net)
8168 kfree(net->dev_name_head);
8169 kfree(net->dev_index_head);
8172 static struct pernet_operations __net_initdata netdev_net_ops = {
8173 .init = netdev_init,
8174 .exit = netdev_exit,
8177 static void __net_exit default_device_exit(struct net *net)
8179 struct net_device *dev, *aux;
8181 * Push all migratable network devices back to the
8182 * initial network namespace
8185 for_each_netdev_safe(net, dev, aux) {
8187 char fb_name[IFNAMSIZ];
8189 /* Ignore unmoveable devices (i.e. loopback) */
8190 if (dev->features & NETIF_F_NETNS_LOCAL)
8193 /* Leave virtual devices for the generic cleanup */
8194 if (dev->rtnl_link_ops)
8197 /* Push remaining network devices to init_net */
8198 snprintf(fb_name, IFNAMSIZ, "dev%d", dev->ifindex);
8199 err = dev_change_net_namespace(dev, &init_net, fb_name);
8201 pr_emerg("%s: failed to move %s to init_net: %d\n",
8202 __func__, dev->name, err);
8209 static void __net_exit rtnl_lock_unregistering(struct list_head *net_list)
8211 /* Return with the rtnl_lock held when there are no network
8212 * devices unregistering in any network namespace in net_list.
8216 DEFINE_WAIT_FUNC(wait, woken_wake_function);
8218 add_wait_queue(&netdev_unregistering_wq, &wait);
8220 unregistering = false;
8222 list_for_each_entry(net, net_list, exit_list) {
8223 if (net->dev_unreg_count > 0) {
8224 unregistering = true;
8232 wait_woken(&wait, TASK_UNINTERRUPTIBLE, MAX_SCHEDULE_TIMEOUT);
8234 remove_wait_queue(&netdev_unregistering_wq, &wait);
8237 static void __net_exit default_device_exit_batch(struct list_head *net_list)
8239 /* At exit all network devices most be removed from a network
8240 * namespace. Do this in the reverse order of registration.
8241 * Do this across as many network namespaces as possible to
8242 * improve batching efficiency.
8244 struct net_device *dev;
8246 LIST_HEAD(dev_kill_list);
8248 /* To prevent network device cleanup code from dereferencing
8249 * loopback devices or network devices that have been freed
8250 * wait here for all pending unregistrations to complete,
8251 * before unregistring the loopback device and allowing the
8252 * network namespace be freed.
8254 * The netdev todo list containing all network devices
8255 * unregistrations that happen in default_device_exit_batch
8256 * will run in the rtnl_unlock() at the end of
8257 * default_device_exit_batch.
8259 rtnl_lock_unregistering(net_list);
8260 list_for_each_entry(net, net_list, exit_list) {
8261 for_each_netdev_reverse(net, dev) {
8262 if (dev->rtnl_link_ops && dev->rtnl_link_ops->dellink)
8263 dev->rtnl_link_ops->dellink(dev, &dev_kill_list);
8265 unregister_netdevice_queue(dev, &dev_kill_list);
8268 unregister_netdevice_many(&dev_kill_list);
8272 static struct pernet_operations __net_initdata default_device_ops = {
8273 .exit = default_device_exit,
8274 .exit_batch = default_device_exit_batch,
8278 * Initialize the DEV module. At boot time this walks the device list and
8279 * unhooks any devices that fail to initialise (normally hardware not
8280 * present) and leaves us with a valid list of present and active devices.
8285 * This is called single threaded during boot, so no need
8286 * to take the rtnl semaphore.
8288 static int __init net_dev_init(void)
8290 int i, rc = -ENOMEM;
8292 BUG_ON(!dev_boot_phase);
8294 if (dev_proc_init())
8297 if (netdev_kobject_init())
8300 INIT_LIST_HEAD(&ptype_all);
8301 for (i = 0; i < PTYPE_HASH_SIZE; i++)
8302 INIT_LIST_HEAD(&ptype_base[i]);
8304 INIT_LIST_HEAD(&offload_base);
8306 if (register_pernet_subsys(&netdev_net_ops))
8310 * Initialise the packet receive queues.
8313 for_each_possible_cpu(i) {
8314 struct work_struct *flush = per_cpu_ptr(&flush_works, i);
8315 struct softnet_data *sd = &per_cpu(softnet_data, i);
8317 INIT_WORK(flush, flush_backlog);
8319 skb_queue_head_init(&sd->input_pkt_queue);
8320 skb_queue_head_init(&sd->process_queue);
8321 INIT_LIST_HEAD(&sd->poll_list);
8322 sd->output_queue_tailp = &sd->output_queue;
8324 sd->csd.func = rps_trigger_softirq;
8329 sd->backlog.poll = process_backlog;
8330 sd->backlog.weight = weight_p;
8335 /* The loopback device is special if any other network devices
8336 * is present in a network namespace the loopback device must
8337 * be present. Since we now dynamically allocate and free the
8338 * loopback device ensure this invariant is maintained by
8339 * keeping the loopback device as the first device on the
8340 * list of network devices. Ensuring the loopback devices
8341 * is the first device that appears and the last network device
8344 if (register_pernet_device(&loopback_net_ops))
8347 if (register_pernet_device(&default_device_ops))
8350 open_softirq(NET_TX_SOFTIRQ, net_tx_action);
8351 open_softirq(NET_RX_SOFTIRQ, net_rx_action);
8353 hotcpu_notifier(dev_cpu_callback, 0);
8360 subsys_initcall(net_dev_init);