2 * NET3 Protocol independent device support routines.
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License
6 * as published by the Free Software Foundation; either version
7 * 2 of the License, or (at your option) any later version.
9 * Derived from the non IP parts of dev.c 1.0.19
11 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
12 * Mark Evans, <evansmp@uhura.aston.ac.uk>
15 * Florian la Roche <rzsfl@rz.uni-sb.de>
16 * Alan Cox <gw4pts@gw4pts.ampr.org>
17 * David Hinds <dahinds@users.sourceforge.net>
18 * Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
19 * Adam Sulmicki <adam@cfar.umd.edu>
20 * Pekka Riikonen <priikone@poesidon.pspt.fi>
23 * D.J. Barrow : Fixed bug where dev->refcnt gets set
24 * to 2 if register_netdev gets called
25 * before net_dev_init & also removed a
26 * few lines of code in the process.
27 * Alan Cox : device private ioctl copies fields back.
28 * Alan Cox : Transmit queue code does relevant
29 * stunts to keep the queue safe.
30 * Alan Cox : Fixed double lock.
31 * Alan Cox : Fixed promisc NULL pointer trap
32 * ???????? : Support the full private ioctl range
33 * Alan Cox : Moved ioctl permission check into
35 * Tim Kordas : SIOCADDMULTI/SIOCDELMULTI
36 * Alan Cox : 100 backlog just doesn't cut it when
37 * you start doing multicast video 8)
38 * Alan Cox : Rewrote net_bh and list manager.
39 * Alan Cox : Fix ETH_P_ALL echoback lengths.
40 * Alan Cox : Took out transmit every packet pass
41 * Saved a few bytes in the ioctl handler
42 * Alan Cox : Network driver sets packet type before
43 * calling netif_rx. Saves a function
45 * Alan Cox : Hashed net_bh()
46 * Richard Kooijman: Timestamp fixes.
47 * Alan Cox : Wrong field in SIOCGIFDSTADDR
48 * Alan Cox : Device lock protection.
49 * Alan Cox : Fixed nasty side effect of device close
51 * Rudi Cilibrasi : Pass the right thing to
53 * Dave Miller : 32bit quantity for the device lock to
54 * make it work out on a Sparc.
55 * Bjorn Ekwall : Added KERNELD hack.
56 * Alan Cox : Cleaned up the backlog initialise.
57 * Craig Metz : SIOCGIFCONF fix if space for under
59 * Thomas Bogendoerfer : Return ENODEV for dev_open, if there
60 * is no device open function.
61 * Andi Kleen : Fix error reporting for SIOCGIFCONF
62 * Michael Chastain : Fix signed/unsigned for SIOCGIFCONF
63 * Cyrus Durgin : Cleaned for KMOD
64 * Adam Sulmicki : Bug Fix : Network Device Unload
65 * A network device unload needs to purge
67 * Paul Rusty Russell : SIOCSIFNAME
68 * Pekka Riikonen : Netdev boot-time settings code
69 * Andrew Morton : Make unregister_netdevice wait
70 * indefinitely on dev->refcnt
71 * J Hadi Salim : - Backlog queue sampling
72 * - netif_rx() feedback
75 #include <asm/uaccess.h>
76 #include <linux/bitops.h>
77 #include <linux/capability.h>
78 #include <linux/cpu.h>
79 #include <linux/types.h>
80 #include <linux/kernel.h>
81 #include <linux/hash.h>
82 #include <linux/slab.h>
83 #include <linux/sched.h>
84 #include <linux/mutex.h>
85 #include <linux/string.h>
87 #include <linux/socket.h>
88 #include <linux/sockios.h>
89 #include <linux/errno.h>
90 #include <linux/interrupt.h>
91 #include <linux/if_ether.h>
92 #include <linux/netdevice.h>
93 #include <linux/etherdevice.h>
94 #include <linux/ethtool.h>
95 #include <linux/notifier.h>
96 #include <linux/skbuff.h>
97 #include <net/net_namespace.h>
99 #include <linux/rtnetlink.h>
100 #include <linux/stat.h>
102 #include <net/dst_metadata.h>
103 #include <net/pkt_sched.h>
104 #include <net/checksum.h>
105 #include <net/xfrm.h>
106 #include <linux/highmem.h>
107 #include <linux/init.h>
108 #include <linux/module.h>
109 #include <linux/netpoll.h>
110 #include <linux/rcupdate.h>
111 #include <linux/delay.h>
112 #include <net/iw_handler.h>
113 #include <asm/current.h>
114 #include <linux/audit.h>
115 #include <linux/dmaengine.h>
116 #include <linux/err.h>
117 #include <linux/ctype.h>
118 #include <linux/if_arp.h>
119 #include <linux/if_vlan.h>
120 #include <linux/ip.h>
122 #include <net/mpls.h>
123 #include <linux/ipv6.h>
124 #include <linux/in.h>
125 #include <linux/jhash.h>
126 #include <linux/random.h>
127 #include <trace/events/napi.h>
128 #include <trace/events/net.h>
129 #include <trace/events/skb.h>
130 #include <linux/pci.h>
131 #include <linux/inetdevice.h>
132 #include <linux/cpu_rmap.h>
133 #include <linux/static_key.h>
134 #include <linux/hashtable.h>
135 #include <linux/vmalloc.h>
136 #include <linux/if_macvlan.h>
137 #include <linux/errqueue.h>
138 #include <linux/hrtimer.h>
139 #include <linux/netfilter_ingress.h>
141 #include "net-sysfs.h"
143 /* Instead of increasing this, you should create a hash table. */
144 #define MAX_GRO_SKBS 8
146 /* This should be increased if a protocol with a bigger head is added. */
147 #define GRO_MAX_HEAD (MAX_HEADER + 128)
149 static DEFINE_SPINLOCK(ptype_lock);
150 static DEFINE_SPINLOCK(offload_lock);
151 struct list_head ptype_base[PTYPE_HASH_SIZE] __read_mostly;
152 struct list_head ptype_all __read_mostly; /* Taps */
153 static struct list_head offload_base __read_mostly;
155 static int netif_rx_internal(struct sk_buff *skb);
156 static int call_netdevice_notifiers_info(unsigned long val,
157 struct net_device *dev,
158 struct netdev_notifier_info *info);
161 * The @dev_base_head list is protected by @dev_base_lock and the rtnl
164 * Pure readers hold dev_base_lock for reading, or rcu_read_lock()
166 * Writers must hold the rtnl semaphore while they loop through the
167 * dev_base_head list, and hold dev_base_lock for writing when they do the
168 * actual updates. This allows pure readers to access the list even
169 * while a writer is preparing to update it.
171 * To put it another way, dev_base_lock is held for writing only to
172 * protect against pure readers; the rtnl semaphore provides the
173 * protection against other writers.
175 * See, for example usages, register_netdevice() and
176 * unregister_netdevice(), which must be called with the rtnl
179 DEFINE_RWLOCK(dev_base_lock);
180 EXPORT_SYMBOL(dev_base_lock);
182 /* protects napi_hash addition/deletion and napi_gen_id */
183 static DEFINE_SPINLOCK(napi_hash_lock);
185 static unsigned int napi_gen_id;
186 static DEFINE_HASHTABLE(napi_hash, 8);
188 static seqcount_t devnet_rename_seq;
190 static inline void dev_base_seq_inc(struct net *net)
192 while (++net->dev_base_seq == 0);
195 static inline struct hlist_head *dev_name_hash(struct net *net, const char *name)
197 unsigned int hash = full_name_hash(name, strnlen(name, IFNAMSIZ));
199 return &net->dev_name_head[hash_32(hash, NETDEV_HASHBITS)];
202 static inline struct hlist_head *dev_index_hash(struct net *net, int ifindex)
204 return &net->dev_index_head[ifindex & (NETDEV_HASHENTRIES - 1)];
207 static inline void rps_lock(struct softnet_data *sd)
210 spin_lock(&sd->input_pkt_queue.lock);
214 static inline void rps_unlock(struct softnet_data *sd)
217 spin_unlock(&sd->input_pkt_queue.lock);
221 /* Device list insertion */
222 static void list_netdevice(struct net_device *dev)
224 struct net *net = dev_net(dev);
228 write_lock_bh(&dev_base_lock);
229 list_add_tail_rcu(&dev->dev_list, &net->dev_base_head);
230 hlist_add_head_rcu(&dev->name_hlist, dev_name_hash(net, dev->name));
231 hlist_add_head_rcu(&dev->index_hlist,
232 dev_index_hash(net, dev->ifindex));
233 write_unlock_bh(&dev_base_lock);
235 dev_base_seq_inc(net);
238 /* Device list removal
239 * caller must respect a RCU grace period before freeing/reusing dev
241 static void unlist_netdevice(struct net_device *dev)
245 /* Unlink dev from the device chain */
246 write_lock_bh(&dev_base_lock);
247 list_del_rcu(&dev->dev_list);
248 hlist_del_rcu(&dev->name_hlist);
249 hlist_del_rcu(&dev->index_hlist);
250 write_unlock_bh(&dev_base_lock);
252 dev_base_seq_inc(dev_net(dev));
259 static RAW_NOTIFIER_HEAD(netdev_chain);
262 * Device drivers call our routines to queue packets here. We empty the
263 * queue in the local softnet handler.
266 DEFINE_PER_CPU_ALIGNED(struct softnet_data, softnet_data);
267 EXPORT_PER_CPU_SYMBOL(softnet_data);
269 #ifdef CONFIG_LOCKDEP
271 * register_netdevice() inits txq->_xmit_lock and sets lockdep class
272 * according to dev->type
274 static const unsigned short netdev_lock_type[] =
275 {ARPHRD_NETROM, ARPHRD_ETHER, ARPHRD_EETHER, ARPHRD_AX25,
276 ARPHRD_PRONET, ARPHRD_CHAOS, ARPHRD_IEEE802, ARPHRD_ARCNET,
277 ARPHRD_APPLETLK, ARPHRD_DLCI, ARPHRD_ATM, ARPHRD_METRICOM,
278 ARPHRD_IEEE1394, ARPHRD_EUI64, ARPHRD_INFINIBAND, ARPHRD_SLIP,
279 ARPHRD_CSLIP, ARPHRD_SLIP6, ARPHRD_CSLIP6, ARPHRD_RSRVD,
280 ARPHRD_ADAPT, ARPHRD_ROSE, ARPHRD_X25, ARPHRD_HWX25,
281 ARPHRD_PPP, ARPHRD_CISCO, ARPHRD_LAPB, ARPHRD_DDCMP,
282 ARPHRD_RAWHDLC, ARPHRD_TUNNEL, ARPHRD_TUNNEL6, ARPHRD_FRAD,
283 ARPHRD_SKIP, ARPHRD_LOOPBACK, ARPHRD_LOCALTLK, ARPHRD_FDDI,
284 ARPHRD_BIF, ARPHRD_SIT, ARPHRD_IPDDP, ARPHRD_IPGRE,
285 ARPHRD_PIMREG, ARPHRD_HIPPI, ARPHRD_ASH, ARPHRD_ECONET,
286 ARPHRD_IRDA, ARPHRD_FCPP, ARPHRD_FCAL, ARPHRD_FCPL,
287 ARPHRD_FCFABRIC, ARPHRD_IEEE80211, ARPHRD_IEEE80211_PRISM,
288 ARPHRD_IEEE80211_RADIOTAP, ARPHRD_PHONET, ARPHRD_PHONET_PIPE,
289 ARPHRD_IEEE802154, ARPHRD_VOID, ARPHRD_NONE};
291 static const char *const netdev_lock_name[] =
292 {"_xmit_NETROM", "_xmit_ETHER", "_xmit_EETHER", "_xmit_AX25",
293 "_xmit_PRONET", "_xmit_CHAOS", "_xmit_IEEE802", "_xmit_ARCNET",
294 "_xmit_APPLETLK", "_xmit_DLCI", "_xmit_ATM", "_xmit_METRICOM",
295 "_xmit_IEEE1394", "_xmit_EUI64", "_xmit_INFINIBAND", "_xmit_SLIP",
296 "_xmit_CSLIP", "_xmit_SLIP6", "_xmit_CSLIP6", "_xmit_RSRVD",
297 "_xmit_ADAPT", "_xmit_ROSE", "_xmit_X25", "_xmit_HWX25",
298 "_xmit_PPP", "_xmit_CISCO", "_xmit_LAPB", "_xmit_DDCMP",
299 "_xmit_RAWHDLC", "_xmit_TUNNEL", "_xmit_TUNNEL6", "_xmit_FRAD",
300 "_xmit_SKIP", "_xmit_LOOPBACK", "_xmit_LOCALTLK", "_xmit_FDDI",
301 "_xmit_BIF", "_xmit_SIT", "_xmit_IPDDP", "_xmit_IPGRE",
302 "_xmit_PIMREG", "_xmit_HIPPI", "_xmit_ASH", "_xmit_ECONET",
303 "_xmit_IRDA", "_xmit_FCPP", "_xmit_FCAL", "_xmit_FCPL",
304 "_xmit_FCFABRIC", "_xmit_IEEE80211", "_xmit_IEEE80211_PRISM",
305 "_xmit_IEEE80211_RADIOTAP", "_xmit_PHONET", "_xmit_PHONET_PIPE",
306 "_xmit_IEEE802154", "_xmit_VOID", "_xmit_NONE"};
308 static struct lock_class_key netdev_xmit_lock_key[ARRAY_SIZE(netdev_lock_type)];
309 static struct lock_class_key netdev_addr_lock_key[ARRAY_SIZE(netdev_lock_type)];
311 static inline unsigned short netdev_lock_pos(unsigned short dev_type)
315 for (i = 0; i < ARRAY_SIZE(netdev_lock_type); i++)
316 if (netdev_lock_type[i] == dev_type)
318 /* the last key is used by default */
319 return ARRAY_SIZE(netdev_lock_type) - 1;
322 static inline void netdev_set_xmit_lockdep_class(spinlock_t *lock,
323 unsigned short dev_type)
327 i = netdev_lock_pos(dev_type);
328 lockdep_set_class_and_name(lock, &netdev_xmit_lock_key[i],
329 netdev_lock_name[i]);
332 static inline void netdev_set_addr_lockdep_class(struct net_device *dev)
336 i = netdev_lock_pos(dev->type);
337 lockdep_set_class_and_name(&dev->addr_list_lock,
338 &netdev_addr_lock_key[i],
339 netdev_lock_name[i]);
342 static inline void netdev_set_xmit_lockdep_class(spinlock_t *lock,
343 unsigned short dev_type)
346 static inline void netdev_set_addr_lockdep_class(struct net_device *dev)
351 /*******************************************************************************
353 Protocol management and registration routines
355 *******************************************************************************/
358 * Add a protocol ID to the list. Now that the input handler is
359 * smarter we can dispense with all the messy stuff that used to be
362 * BEWARE!!! Protocol handlers, mangling input packets,
363 * MUST BE last in hash buckets and checking protocol handlers
364 * MUST start from promiscuous ptype_all chain in net_bh.
365 * It is true now, do not change it.
366 * Explanation follows: if protocol handler, mangling packet, will
367 * be the first on list, it is not able to sense, that packet
368 * is cloned and should be copied-on-write, so that it will
369 * change it and subsequent readers will get broken packet.
373 static inline struct list_head *ptype_head(const struct packet_type *pt)
375 if (pt->type == htons(ETH_P_ALL))
376 return pt->dev ? &pt->dev->ptype_all : &ptype_all;
378 return pt->dev ? &pt->dev->ptype_specific :
379 &ptype_base[ntohs(pt->type) & PTYPE_HASH_MASK];
383 * dev_add_pack - add packet handler
384 * @pt: packet type declaration
386 * Add a protocol handler to the networking stack. The passed &packet_type
387 * is linked into kernel lists and may not be freed until it has been
388 * removed from the kernel lists.
390 * This call does not sleep therefore it can not
391 * guarantee all CPU's that are in middle of receiving packets
392 * will see the new packet type (until the next received packet).
395 void dev_add_pack(struct packet_type *pt)
397 struct list_head *head = ptype_head(pt);
399 spin_lock(&ptype_lock);
400 list_add_rcu(&pt->list, head);
401 spin_unlock(&ptype_lock);
403 EXPORT_SYMBOL(dev_add_pack);
406 * __dev_remove_pack - remove packet handler
407 * @pt: packet type declaration
409 * Remove a protocol handler that was previously added to the kernel
410 * protocol handlers by dev_add_pack(). The passed &packet_type is removed
411 * from the kernel lists and can be freed or reused once this function
414 * The packet type might still be in use by receivers
415 * and must not be freed until after all the CPU's have gone
416 * through a quiescent state.
418 void __dev_remove_pack(struct packet_type *pt)
420 struct list_head *head = ptype_head(pt);
421 struct packet_type *pt1;
423 spin_lock(&ptype_lock);
425 list_for_each_entry(pt1, head, list) {
427 list_del_rcu(&pt->list);
432 pr_warn("dev_remove_pack: %p not found\n", pt);
434 spin_unlock(&ptype_lock);
436 EXPORT_SYMBOL(__dev_remove_pack);
439 * dev_remove_pack - remove packet handler
440 * @pt: packet type declaration
442 * Remove a protocol handler that was previously added to the kernel
443 * protocol handlers by dev_add_pack(). The passed &packet_type is removed
444 * from the kernel lists and can be freed or reused once this function
447 * This call sleeps to guarantee that no CPU is looking at the packet
450 void dev_remove_pack(struct packet_type *pt)
452 __dev_remove_pack(pt);
456 EXPORT_SYMBOL(dev_remove_pack);
460 * dev_add_offload - register offload handlers
461 * @po: protocol offload declaration
463 * Add protocol offload handlers to the networking stack. The passed
464 * &proto_offload is linked into kernel lists and may not be freed until
465 * it has been removed from the kernel lists.
467 * This call does not sleep therefore it can not
468 * guarantee all CPU's that are in middle of receiving packets
469 * will see the new offload handlers (until the next received packet).
471 void dev_add_offload(struct packet_offload *po)
473 struct packet_offload *elem;
475 spin_lock(&offload_lock);
476 list_for_each_entry(elem, &offload_base, list) {
477 if (po->priority < elem->priority)
480 list_add_rcu(&po->list, elem->list.prev);
481 spin_unlock(&offload_lock);
483 EXPORT_SYMBOL(dev_add_offload);
486 * __dev_remove_offload - remove offload handler
487 * @po: packet offload declaration
489 * Remove a protocol offload handler that was previously added to the
490 * kernel offload handlers by dev_add_offload(). The passed &offload_type
491 * is removed from the kernel lists and can be freed or reused once this
494 * The packet type might still be in use by receivers
495 * and must not be freed until after all the CPU's have gone
496 * through a quiescent state.
498 static void __dev_remove_offload(struct packet_offload *po)
500 struct list_head *head = &offload_base;
501 struct packet_offload *po1;
503 spin_lock(&offload_lock);
505 list_for_each_entry(po1, head, list) {
507 list_del_rcu(&po->list);
512 pr_warn("dev_remove_offload: %p not found\n", po);
514 spin_unlock(&offload_lock);
518 * dev_remove_offload - remove packet offload handler
519 * @po: packet offload declaration
521 * Remove a packet offload handler that was previously added to the kernel
522 * offload handlers by dev_add_offload(). The passed &offload_type is
523 * removed from the kernel lists and can be freed or reused once this
526 * This call sleeps to guarantee that no CPU is looking at the packet
529 void dev_remove_offload(struct packet_offload *po)
531 __dev_remove_offload(po);
535 EXPORT_SYMBOL(dev_remove_offload);
537 /******************************************************************************
539 Device Boot-time Settings Routines
541 *******************************************************************************/
543 /* Boot time configuration table */
544 static struct netdev_boot_setup dev_boot_setup[NETDEV_BOOT_SETUP_MAX];
547 * netdev_boot_setup_add - add new setup entry
548 * @name: name of the device
549 * @map: configured settings for the device
551 * Adds new setup entry to the dev_boot_setup list. The function
552 * returns 0 on error and 1 on success. This is a generic routine to
555 static int netdev_boot_setup_add(char *name, struct ifmap *map)
557 struct netdev_boot_setup *s;
561 for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++) {
562 if (s[i].name[0] == '\0' || s[i].name[0] == ' ') {
563 memset(s[i].name, 0, sizeof(s[i].name));
564 strlcpy(s[i].name, name, IFNAMSIZ);
565 memcpy(&s[i].map, map, sizeof(s[i].map));
570 return i >= NETDEV_BOOT_SETUP_MAX ? 0 : 1;
574 * netdev_boot_setup_check - check boot time settings
575 * @dev: the netdevice
577 * Check boot time settings for the device.
578 * The found settings are set for the device to be used
579 * later in the device probing.
580 * Returns 0 if no settings found, 1 if they are.
582 int netdev_boot_setup_check(struct net_device *dev)
584 struct netdev_boot_setup *s = dev_boot_setup;
587 for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++) {
588 if (s[i].name[0] != '\0' && s[i].name[0] != ' ' &&
589 !strcmp(dev->name, s[i].name)) {
590 dev->irq = s[i].map.irq;
591 dev->base_addr = s[i].map.base_addr;
592 dev->mem_start = s[i].map.mem_start;
593 dev->mem_end = s[i].map.mem_end;
599 EXPORT_SYMBOL(netdev_boot_setup_check);
603 * netdev_boot_base - get address from boot time settings
604 * @prefix: prefix for network device
605 * @unit: id for network device
607 * Check boot time settings for the base address of device.
608 * The found settings are set for the device to be used
609 * later in the device probing.
610 * Returns 0 if no settings found.
612 unsigned long netdev_boot_base(const char *prefix, int unit)
614 const struct netdev_boot_setup *s = dev_boot_setup;
618 sprintf(name, "%s%d", prefix, unit);
621 * If device already registered then return base of 1
622 * to indicate not to probe for this interface
624 if (__dev_get_by_name(&init_net, name))
627 for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++)
628 if (!strcmp(name, s[i].name))
629 return s[i].map.base_addr;
634 * Saves at boot time configured settings for any netdevice.
636 int __init netdev_boot_setup(char *str)
641 str = get_options(str, ARRAY_SIZE(ints), ints);
646 memset(&map, 0, sizeof(map));
650 map.base_addr = ints[2];
652 map.mem_start = ints[3];
654 map.mem_end = ints[4];
656 /* Add new entry to the list */
657 return netdev_boot_setup_add(str, &map);
660 __setup("netdev=", netdev_boot_setup);
662 /*******************************************************************************
664 Device Interface Subroutines
666 *******************************************************************************/
669 * dev_get_iflink - get 'iflink' value of a interface
670 * @dev: targeted interface
672 * Indicates the ifindex the interface is linked to.
673 * Physical interfaces have the same 'ifindex' and 'iflink' values.
676 int dev_get_iflink(const struct net_device *dev)
678 if (dev->netdev_ops && dev->netdev_ops->ndo_get_iflink)
679 return dev->netdev_ops->ndo_get_iflink(dev);
683 EXPORT_SYMBOL(dev_get_iflink);
686 * dev_fill_metadata_dst - Retrieve tunnel egress information.
687 * @dev: targeted interface
690 * For better visibility of tunnel traffic OVS needs to retrieve
691 * egress tunnel information for a packet. Following API allows
692 * user to get this info.
694 int dev_fill_metadata_dst(struct net_device *dev, struct sk_buff *skb)
696 struct ip_tunnel_info *info;
698 if (!dev->netdev_ops || !dev->netdev_ops->ndo_fill_metadata_dst)
701 info = skb_tunnel_info_unclone(skb);
704 if (unlikely(!(info->mode & IP_TUNNEL_INFO_TX)))
707 return dev->netdev_ops->ndo_fill_metadata_dst(dev, skb);
709 EXPORT_SYMBOL_GPL(dev_fill_metadata_dst);
712 * __dev_get_by_name - find a device by its name
713 * @net: the applicable net namespace
714 * @name: name to find
716 * Find an interface by name. Must be called under RTNL semaphore
717 * or @dev_base_lock. If the name is found a pointer to the device
718 * is returned. If the name is not found then %NULL is returned. The
719 * reference counters are not incremented so the caller must be
720 * careful with locks.
723 struct net_device *__dev_get_by_name(struct net *net, const char *name)
725 struct net_device *dev;
726 struct hlist_head *head = dev_name_hash(net, name);
728 hlist_for_each_entry(dev, head, name_hlist)
729 if (!strncmp(dev->name, name, IFNAMSIZ))
734 EXPORT_SYMBOL(__dev_get_by_name);
737 * dev_get_by_name_rcu - find a device by its name
738 * @net: the applicable net namespace
739 * @name: name to find
741 * Find an interface by name.
742 * If the name is found a pointer to the device is returned.
743 * If the name is not found then %NULL is returned.
744 * The reference counters are not incremented so the caller must be
745 * careful with locks. The caller must hold RCU lock.
748 struct net_device *dev_get_by_name_rcu(struct net *net, const char *name)
750 struct net_device *dev;
751 struct hlist_head *head = dev_name_hash(net, name);
753 hlist_for_each_entry_rcu(dev, head, name_hlist)
754 if (!strncmp(dev->name, name, IFNAMSIZ))
759 EXPORT_SYMBOL(dev_get_by_name_rcu);
762 * dev_get_by_name - find a device by its name
763 * @net: the applicable net namespace
764 * @name: name to find
766 * Find an interface by name. This can be called from any
767 * context and does its own locking. The returned handle has
768 * the usage count incremented and the caller must use dev_put() to
769 * release it when it is no longer needed. %NULL is returned if no
770 * matching device is found.
773 struct net_device *dev_get_by_name(struct net *net, const char *name)
775 struct net_device *dev;
778 dev = dev_get_by_name_rcu(net, name);
784 EXPORT_SYMBOL(dev_get_by_name);
787 * __dev_get_by_index - find a device by its ifindex
788 * @net: the applicable net namespace
789 * @ifindex: index of device
791 * Search for an interface by index. Returns %NULL if the device
792 * is not found or a pointer to the device. The device has not
793 * had its reference counter increased so the caller must be careful
794 * about locking. The caller must hold either the RTNL semaphore
798 struct net_device *__dev_get_by_index(struct net *net, int ifindex)
800 struct net_device *dev;
801 struct hlist_head *head = dev_index_hash(net, ifindex);
803 hlist_for_each_entry(dev, head, index_hlist)
804 if (dev->ifindex == ifindex)
809 EXPORT_SYMBOL(__dev_get_by_index);
812 * dev_get_by_index_rcu - find a device by its ifindex
813 * @net: the applicable net namespace
814 * @ifindex: index of device
816 * Search for an interface by index. Returns %NULL if the device
817 * is not found or a pointer to the device. The device has not
818 * had its reference counter increased so the caller must be careful
819 * about locking. The caller must hold RCU lock.
822 struct net_device *dev_get_by_index_rcu(struct net *net, int ifindex)
824 struct net_device *dev;
825 struct hlist_head *head = dev_index_hash(net, ifindex);
827 hlist_for_each_entry_rcu(dev, head, index_hlist)
828 if (dev->ifindex == ifindex)
833 EXPORT_SYMBOL(dev_get_by_index_rcu);
837 * dev_get_by_index - find a device by its ifindex
838 * @net: the applicable net namespace
839 * @ifindex: index of device
841 * Search for an interface by index. Returns NULL if the device
842 * is not found or a pointer to the device. The device returned has
843 * had a reference added and the pointer is safe until the user calls
844 * dev_put to indicate they have finished with it.
847 struct net_device *dev_get_by_index(struct net *net, int ifindex)
849 struct net_device *dev;
852 dev = dev_get_by_index_rcu(net, ifindex);
858 EXPORT_SYMBOL(dev_get_by_index);
861 * netdev_get_name - get a netdevice name, knowing its ifindex.
862 * @net: network namespace
863 * @name: a pointer to the buffer where the name will be stored.
864 * @ifindex: the ifindex of the interface to get the name from.
866 * The use of raw_seqcount_begin() and cond_resched() before
867 * retrying is required as we want to give the writers a chance
868 * to complete when CONFIG_PREEMPT is not set.
870 int netdev_get_name(struct net *net, char *name, int ifindex)
872 struct net_device *dev;
876 seq = raw_seqcount_begin(&devnet_rename_seq);
878 dev = dev_get_by_index_rcu(net, ifindex);
884 strcpy(name, dev->name);
886 if (read_seqcount_retry(&devnet_rename_seq, seq)) {
895 * dev_getbyhwaddr_rcu - find a device by its hardware address
896 * @net: the applicable net namespace
897 * @type: media type of device
898 * @ha: hardware address
900 * Search for an interface by MAC address. Returns NULL if the device
901 * is not found or a pointer to the device.
902 * The caller must hold RCU or RTNL.
903 * The returned device has not had its ref count increased
904 * and the caller must therefore be careful about locking
908 struct net_device *dev_getbyhwaddr_rcu(struct net *net, unsigned short type,
911 struct net_device *dev;
913 for_each_netdev_rcu(net, dev)
914 if (dev->type == type &&
915 !memcmp(dev->dev_addr, ha, dev->addr_len))
920 EXPORT_SYMBOL(dev_getbyhwaddr_rcu);
922 struct net_device *__dev_getfirstbyhwtype(struct net *net, unsigned short type)
924 struct net_device *dev;
927 for_each_netdev(net, dev)
928 if (dev->type == type)
933 EXPORT_SYMBOL(__dev_getfirstbyhwtype);
935 struct net_device *dev_getfirstbyhwtype(struct net *net, unsigned short type)
937 struct net_device *dev, *ret = NULL;
940 for_each_netdev_rcu(net, dev)
941 if (dev->type == type) {
949 EXPORT_SYMBOL(dev_getfirstbyhwtype);
952 * __dev_get_by_flags - find any device with given flags
953 * @net: the applicable net namespace
954 * @if_flags: IFF_* values
955 * @mask: bitmask of bits in if_flags to check
957 * Search for any interface with the given flags. Returns NULL if a device
958 * is not found or a pointer to the device. Must be called inside
959 * rtnl_lock(), and result refcount is unchanged.
962 struct net_device *__dev_get_by_flags(struct net *net, unsigned short if_flags,
965 struct net_device *dev, *ret;
970 for_each_netdev(net, dev) {
971 if (((dev->flags ^ if_flags) & mask) == 0) {
978 EXPORT_SYMBOL(__dev_get_by_flags);
981 * dev_valid_name - check if name is okay for network device
984 * Network device names need to be valid file names to
985 * to allow sysfs to work. We also disallow any kind of
988 bool dev_valid_name(const char *name)
992 if (strlen(name) >= IFNAMSIZ)
994 if (!strcmp(name, ".") || !strcmp(name, ".."))
998 if (*name == '/' || *name == ':' || isspace(*name))
1004 EXPORT_SYMBOL(dev_valid_name);
1007 * __dev_alloc_name - allocate a name for a device
1008 * @net: network namespace to allocate the device name in
1009 * @name: name format string
1010 * @buf: scratch buffer and result name string
1012 * Passed a format string - eg "lt%d" it will try and find a suitable
1013 * id. It scans list of devices to build up a free map, then chooses
1014 * the first empty slot. The caller must hold the dev_base or rtnl lock
1015 * while allocating the name and adding the device in order to avoid
1017 * Limited to bits_per_byte * page size devices (ie 32K on most platforms).
1018 * Returns the number of the unit assigned or a negative errno code.
1021 static int __dev_alloc_name(struct net *net, const char *name, char *buf)
1025 const int max_netdevices = 8*PAGE_SIZE;
1026 unsigned long *inuse;
1027 struct net_device *d;
1029 p = strnchr(name, IFNAMSIZ-1, '%');
1032 * Verify the string as this thing may have come from
1033 * the user. There must be either one "%d" and no other "%"
1036 if (p[1] != 'd' || strchr(p + 2, '%'))
1039 /* Use one page as a bit array of possible slots */
1040 inuse = (unsigned long *) get_zeroed_page(GFP_ATOMIC);
1044 for_each_netdev(net, d) {
1045 if (!sscanf(d->name, name, &i))
1047 if (i < 0 || i >= max_netdevices)
1050 /* avoid cases where sscanf is not exact inverse of printf */
1051 snprintf(buf, IFNAMSIZ, name, i);
1052 if (!strncmp(buf, d->name, IFNAMSIZ))
1056 i = find_first_zero_bit(inuse, max_netdevices);
1057 free_page((unsigned long) inuse);
1061 snprintf(buf, IFNAMSIZ, name, i);
1062 if (!__dev_get_by_name(net, buf))
1065 /* It is possible to run out of possible slots
1066 * when the name is long and there isn't enough space left
1067 * for the digits, or if all bits are used.
1073 * dev_alloc_name - allocate a name for a device
1075 * @name: name format string
1077 * Passed a format string - eg "lt%d" it will try and find a suitable
1078 * id. It scans list of devices to build up a free map, then chooses
1079 * the first empty slot. The caller must hold the dev_base or rtnl lock
1080 * while allocating the name and adding the device in order to avoid
1082 * Limited to bits_per_byte * page size devices (ie 32K on most platforms).
1083 * Returns the number of the unit assigned or a negative errno code.
1086 int dev_alloc_name(struct net_device *dev, const char *name)
1092 BUG_ON(!dev_net(dev));
1094 ret = __dev_alloc_name(net, name, buf);
1096 strlcpy(dev->name, buf, IFNAMSIZ);
1099 EXPORT_SYMBOL(dev_alloc_name);
1101 static int dev_alloc_name_ns(struct net *net,
1102 struct net_device *dev,
1108 ret = __dev_alloc_name(net, name, buf);
1110 strlcpy(dev->name, buf, IFNAMSIZ);
1114 static int dev_get_valid_name(struct net *net,
1115 struct net_device *dev,
1120 if (!dev_valid_name(name))
1123 if (strchr(name, '%'))
1124 return dev_alloc_name_ns(net, dev, name);
1125 else if (__dev_get_by_name(net, name))
1127 else if (dev->name != name)
1128 strlcpy(dev->name, name, IFNAMSIZ);
1134 * dev_change_name - change name of a device
1136 * @newname: name (or format string) must be at least IFNAMSIZ
1138 * Change name of a device, can pass format strings "eth%d".
1141 int dev_change_name(struct net_device *dev, const char *newname)
1143 unsigned char old_assign_type;
1144 char oldname[IFNAMSIZ];
1150 BUG_ON(!dev_net(dev));
1153 if (dev->flags & IFF_UP)
1156 write_seqcount_begin(&devnet_rename_seq);
1158 if (strncmp(newname, dev->name, IFNAMSIZ) == 0) {
1159 write_seqcount_end(&devnet_rename_seq);
1163 memcpy(oldname, dev->name, IFNAMSIZ);
1165 err = dev_get_valid_name(net, dev, newname);
1167 write_seqcount_end(&devnet_rename_seq);
1171 if (oldname[0] && !strchr(oldname, '%'))
1172 netdev_info(dev, "renamed from %s\n", oldname);
1174 old_assign_type = dev->name_assign_type;
1175 dev->name_assign_type = NET_NAME_RENAMED;
1178 ret = device_rename(&dev->dev, dev->name);
1180 memcpy(dev->name, oldname, IFNAMSIZ);
1181 dev->name_assign_type = old_assign_type;
1182 write_seqcount_end(&devnet_rename_seq);
1186 write_seqcount_end(&devnet_rename_seq);
1188 netdev_adjacent_rename_links(dev, oldname);
1190 write_lock_bh(&dev_base_lock);
1191 hlist_del_rcu(&dev->name_hlist);
1192 write_unlock_bh(&dev_base_lock);
1196 write_lock_bh(&dev_base_lock);
1197 hlist_add_head_rcu(&dev->name_hlist, dev_name_hash(net, dev->name));
1198 write_unlock_bh(&dev_base_lock);
1200 ret = call_netdevice_notifiers(NETDEV_CHANGENAME, dev);
1201 ret = notifier_to_errno(ret);
1204 /* err >= 0 after dev_alloc_name() or stores the first errno */
1207 write_seqcount_begin(&devnet_rename_seq);
1208 memcpy(dev->name, oldname, IFNAMSIZ);
1209 memcpy(oldname, newname, IFNAMSIZ);
1210 dev->name_assign_type = old_assign_type;
1211 old_assign_type = NET_NAME_RENAMED;
1214 pr_err("%s: name change rollback failed: %d\n",
1223 * dev_set_alias - change ifalias of a device
1225 * @alias: name up to IFALIASZ
1226 * @len: limit of bytes to copy from info
1228 * Set ifalias for a device,
1230 int dev_set_alias(struct net_device *dev, const char *alias, size_t len)
1236 if (len >= IFALIASZ)
1240 kfree(dev->ifalias);
1241 dev->ifalias = NULL;
1245 new_ifalias = krealloc(dev->ifalias, len + 1, GFP_KERNEL);
1248 dev->ifalias = new_ifalias;
1250 strlcpy(dev->ifalias, alias, len+1);
1256 * netdev_features_change - device changes features
1257 * @dev: device to cause notification
1259 * Called to indicate a device has changed features.
1261 void netdev_features_change(struct net_device *dev)
1263 call_netdevice_notifiers(NETDEV_FEAT_CHANGE, dev);
1265 EXPORT_SYMBOL(netdev_features_change);
1268 * netdev_state_change - device changes state
1269 * @dev: device to cause notification
1271 * Called to indicate a device has changed state. This function calls
1272 * the notifier chains for netdev_chain and sends a NEWLINK message
1273 * to the routing socket.
1275 void netdev_state_change(struct net_device *dev)
1277 if (dev->flags & IFF_UP) {
1278 struct netdev_notifier_change_info change_info;
1280 change_info.flags_changed = 0;
1281 call_netdevice_notifiers_info(NETDEV_CHANGE, dev,
1283 rtmsg_ifinfo(RTM_NEWLINK, dev, 0, GFP_KERNEL);
1286 EXPORT_SYMBOL(netdev_state_change);
1289 * netdev_notify_peers - notify network peers about existence of @dev
1290 * @dev: network device
1292 * Generate traffic such that interested network peers are aware of
1293 * @dev, such as by generating a gratuitous ARP. This may be used when
1294 * a device wants to inform the rest of the network about some sort of
1295 * reconfiguration such as a failover event or virtual machine
1298 void netdev_notify_peers(struct net_device *dev)
1301 call_netdevice_notifiers(NETDEV_NOTIFY_PEERS, dev);
1304 EXPORT_SYMBOL(netdev_notify_peers);
1306 static int __dev_open(struct net_device *dev)
1308 const struct net_device_ops *ops = dev->netdev_ops;
1313 if (!netif_device_present(dev))
1316 /* Block netpoll from trying to do any rx path servicing.
1317 * If we don't do this there is a chance ndo_poll_controller
1318 * or ndo_poll may be running while we open the device
1320 netpoll_poll_disable(dev);
1322 ret = call_netdevice_notifiers(NETDEV_PRE_UP, dev);
1323 ret = notifier_to_errno(ret);
1327 set_bit(__LINK_STATE_START, &dev->state);
1329 if (ops->ndo_validate_addr)
1330 ret = ops->ndo_validate_addr(dev);
1332 if (!ret && ops->ndo_open)
1333 ret = ops->ndo_open(dev);
1335 netpoll_poll_enable(dev);
1338 clear_bit(__LINK_STATE_START, &dev->state);
1340 dev->flags |= IFF_UP;
1341 dev_set_rx_mode(dev);
1343 add_device_randomness(dev->dev_addr, dev->addr_len);
1350 * dev_open - prepare an interface for use.
1351 * @dev: device to open
1353 * Takes a device from down to up state. The device's private open
1354 * function is invoked and then the multicast lists are loaded. Finally
1355 * the device is moved into the up state and a %NETDEV_UP message is
1356 * sent to the netdev notifier chain.
1358 * Calling this function on an active interface is a nop. On a failure
1359 * a negative errno code is returned.
1361 int dev_open(struct net_device *dev)
1365 if (dev->flags & IFF_UP)
1368 ret = __dev_open(dev);
1372 rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP|IFF_RUNNING, GFP_KERNEL);
1373 call_netdevice_notifiers(NETDEV_UP, dev);
1377 EXPORT_SYMBOL(dev_open);
1379 static int __dev_close_many(struct list_head *head)
1381 struct net_device *dev;
1386 list_for_each_entry(dev, head, close_list) {
1387 /* Temporarily disable netpoll until the interface is down */
1388 netpoll_poll_disable(dev);
1390 call_netdevice_notifiers(NETDEV_GOING_DOWN, dev);
1392 clear_bit(__LINK_STATE_START, &dev->state);
1394 /* Synchronize to scheduled poll. We cannot touch poll list, it
1395 * can be even on different cpu. So just clear netif_running().
1397 * dev->stop() will invoke napi_disable() on all of it's
1398 * napi_struct instances on this device.
1400 smp_mb__after_atomic(); /* Commit netif_running(). */
1403 dev_deactivate_many(head);
1405 list_for_each_entry(dev, head, close_list) {
1406 const struct net_device_ops *ops = dev->netdev_ops;
1409 * Call the device specific close. This cannot fail.
1410 * Only if device is UP
1412 * We allow it to be called even after a DETACH hot-plug
1418 dev->flags &= ~IFF_UP;
1419 netpoll_poll_enable(dev);
1425 static int __dev_close(struct net_device *dev)
1430 list_add(&dev->close_list, &single);
1431 retval = __dev_close_many(&single);
1437 int dev_close_many(struct list_head *head, bool unlink)
1439 struct net_device *dev, *tmp;
1441 /* Remove the devices that don't need to be closed */
1442 list_for_each_entry_safe(dev, tmp, head, close_list)
1443 if (!(dev->flags & IFF_UP))
1444 list_del_init(&dev->close_list);
1446 __dev_close_many(head);
1448 list_for_each_entry_safe(dev, tmp, head, close_list) {
1449 rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP|IFF_RUNNING, GFP_KERNEL);
1450 call_netdevice_notifiers(NETDEV_DOWN, dev);
1452 list_del_init(&dev->close_list);
1457 EXPORT_SYMBOL(dev_close_many);
1460 * dev_close - shutdown an interface.
1461 * @dev: device to shutdown
1463 * This function moves an active device into down state. A
1464 * %NETDEV_GOING_DOWN is sent to the netdev notifier chain. The device
1465 * is then deactivated and finally a %NETDEV_DOWN is sent to the notifier
1468 int dev_close(struct net_device *dev)
1470 if (dev->flags & IFF_UP) {
1473 list_add(&dev->close_list, &single);
1474 dev_close_many(&single, true);
1479 EXPORT_SYMBOL(dev_close);
1483 * dev_disable_lro - disable Large Receive Offload on a device
1486 * Disable Large Receive Offload (LRO) on a net device. Must be
1487 * called under RTNL. This is needed if received packets may be
1488 * forwarded to another interface.
1490 void dev_disable_lro(struct net_device *dev)
1492 struct net_device *lower_dev;
1493 struct list_head *iter;
1495 dev->wanted_features &= ~NETIF_F_LRO;
1496 netdev_update_features(dev);
1498 if (unlikely(dev->features & NETIF_F_LRO))
1499 netdev_WARN(dev, "failed to disable LRO!\n");
1501 netdev_for_each_lower_dev(dev, lower_dev, iter)
1502 dev_disable_lro(lower_dev);
1504 EXPORT_SYMBOL(dev_disable_lro);
1506 static int call_netdevice_notifier(struct notifier_block *nb, unsigned long val,
1507 struct net_device *dev)
1509 struct netdev_notifier_info info;
1511 netdev_notifier_info_init(&info, dev);
1512 return nb->notifier_call(nb, val, &info);
1515 static int dev_boot_phase = 1;
1518 * register_netdevice_notifier - register a network notifier block
1521 * Register a notifier to be called when network device events occur.
1522 * The notifier passed is linked into the kernel structures and must
1523 * not be reused until it has been unregistered. A negative errno code
1524 * is returned on a failure.
1526 * When registered all registration and up events are replayed
1527 * to the new notifier to allow device to have a race free
1528 * view of the network device list.
1531 int register_netdevice_notifier(struct notifier_block *nb)
1533 struct net_device *dev;
1534 struct net_device *last;
1539 err = raw_notifier_chain_register(&netdev_chain, nb);
1545 for_each_netdev(net, dev) {
1546 err = call_netdevice_notifier(nb, NETDEV_REGISTER, dev);
1547 err = notifier_to_errno(err);
1551 if (!(dev->flags & IFF_UP))
1554 call_netdevice_notifier(nb, NETDEV_UP, dev);
1565 for_each_netdev(net, dev) {
1569 if (dev->flags & IFF_UP) {
1570 call_netdevice_notifier(nb, NETDEV_GOING_DOWN,
1572 call_netdevice_notifier(nb, NETDEV_DOWN, dev);
1574 call_netdevice_notifier(nb, NETDEV_UNREGISTER, dev);
1579 raw_notifier_chain_unregister(&netdev_chain, nb);
1582 EXPORT_SYMBOL(register_netdevice_notifier);
1585 * unregister_netdevice_notifier - unregister a network notifier block
1588 * Unregister a notifier previously registered by
1589 * register_netdevice_notifier(). The notifier is unlinked into the
1590 * kernel structures and may then be reused. A negative errno code
1591 * is returned on a failure.
1593 * After unregistering unregister and down device events are synthesized
1594 * for all devices on the device list to the removed notifier to remove
1595 * the need for special case cleanup code.
1598 int unregister_netdevice_notifier(struct notifier_block *nb)
1600 struct net_device *dev;
1605 err = raw_notifier_chain_unregister(&netdev_chain, nb);
1610 for_each_netdev(net, dev) {
1611 if (dev->flags & IFF_UP) {
1612 call_netdevice_notifier(nb, NETDEV_GOING_DOWN,
1614 call_netdevice_notifier(nb, NETDEV_DOWN, dev);
1616 call_netdevice_notifier(nb, NETDEV_UNREGISTER, dev);
1623 EXPORT_SYMBOL(unregister_netdevice_notifier);
1626 * call_netdevice_notifiers_info - call all network notifier blocks
1627 * @val: value passed unmodified to notifier function
1628 * @dev: net_device pointer passed unmodified to notifier function
1629 * @info: notifier information data
1631 * Call all network notifier blocks. Parameters and return value
1632 * are as for raw_notifier_call_chain().
1635 static int call_netdevice_notifiers_info(unsigned long val,
1636 struct net_device *dev,
1637 struct netdev_notifier_info *info)
1640 netdev_notifier_info_init(info, dev);
1641 return raw_notifier_call_chain(&netdev_chain, val, info);
1645 * call_netdevice_notifiers - call all network notifier blocks
1646 * @val: value passed unmodified to notifier function
1647 * @dev: net_device pointer passed unmodified to notifier function
1649 * Call all network notifier blocks. Parameters and return value
1650 * are as for raw_notifier_call_chain().
1653 int call_netdevice_notifiers(unsigned long val, struct net_device *dev)
1655 struct netdev_notifier_info info;
1657 return call_netdevice_notifiers_info(val, dev, &info);
1659 EXPORT_SYMBOL(call_netdevice_notifiers);
1661 #ifdef CONFIG_NET_INGRESS
1662 static struct static_key ingress_needed __read_mostly;
1664 void net_inc_ingress_queue(void)
1666 static_key_slow_inc(&ingress_needed);
1668 EXPORT_SYMBOL_GPL(net_inc_ingress_queue);
1670 void net_dec_ingress_queue(void)
1672 static_key_slow_dec(&ingress_needed);
1674 EXPORT_SYMBOL_GPL(net_dec_ingress_queue);
1677 static struct static_key netstamp_needed __read_mostly;
1678 #ifdef HAVE_JUMP_LABEL
1679 /* We are not allowed to call static_key_slow_dec() from irq context
1680 * If net_disable_timestamp() is called from irq context, defer the
1681 * static_key_slow_dec() calls.
1683 static atomic_t netstamp_needed_deferred;
1686 void net_enable_timestamp(void)
1688 #ifdef HAVE_JUMP_LABEL
1689 int deferred = atomic_xchg(&netstamp_needed_deferred, 0);
1693 static_key_slow_dec(&netstamp_needed);
1697 static_key_slow_inc(&netstamp_needed);
1699 EXPORT_SYMBOL(net_enable_timestamp);
1701 void net_disable_timestamp(void)
1703 #ifdef HAVE_JUMP_LABEL
1704 if (in_interrupt()) {
1705 atomic_inc(&netstamp_needed_deferred);
1709 static_key_slow_dec(&netstamp_needed);
1711 EXPORT_SYMBOL(net_disable_timestamp);
1713 static inline void net_timestamp_set(struct sk_buff *skb)
1715 skb->tstamp.tv64 = 0;
1716 if (static_key_false(&netstamp_needed))
1717 __net_timestamp(skb);
1720 #define net_timestamp_check(COND, SKB) \
1721 if (static_key_false(&netstamp_needed)) { \
1722 if ((COND) && !(SKB)->tstamp.tv64) \
1723 __net_timestamp(SKB); \
1726 bool is_skb_forwardable(struct net_device *dev, struct sk_buff *skb)
1730 if (!(dev->flags & IFF_UP))
1733 len = dev->mtu + dev->hard_header_len + VLAN_HLEN;
1734 if (skb->len <= len)
1737 /* if TSO is enabled, we don't care about the length as the packet
1738 * could be forwarded without being segmented before
1740 if (skb_is_gso(skb))
1745 EXPORT_SYMBOL_GPL(is_skb_forwardable);
1747 int __dev_forward_skb(struct net_device *dev, struct sk_buff *skb)
1749 if (skb_orphan_frags(skb, GFP_ATOMIC) ||
1750 unlikely(!is_skb_forwardable(dev, skb))) {
1751 atomic_long_inc(&dev->rx_dropped);
1756 skb_scrub_packet(skb, true);
1758 skb->protocol = eth_type_trans(skb, dev);
1759 skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN);
1763 EXPORT_SYMBOL_GPL(__dev_forward_skb);
1766 * dev_forward_skb - loopback an skb to another netif
1768 * @dev: destination network device
1769 * @skb: buffer to forward
1772 * NET_RX_SUCCESS (no congestion)
1773 * NET_RX_DROP (packet was dropped, but freed)
1775 * dev_forward_skb can be used for injecting an skb from the
1776 * start_xmit function of one device into the receive queue
1777 * of another device.
1779 * The receiving device may be in another namespace, so
1780 * we have to clear all information in the skb that could
1781 * impact namespace isolation.
1783 int dev_forward_skb(struct net_device *dev, struct sk_buff *skb)
1785 return __dev_forward_skb(dev, skb) ?: netif_rx_internal(skb);
1787 EXPORT_SYMBOL_GPL(dev_forward_skb);
1789 static inline int deliver_skb(struct sk_buff *skb,
1790 struct packet_type *pt_prev,
1791 struct net_device *orig_dev)
1793 if (unlikely(skb_orphan_frags(skb, GFP_ATOMIC)))
1795 atomic_inc(&skb->users);
1796 return pt_prev->func(skb, skb->dev, pt_prev, orig_dev);
1799 static inline void deliver_ptype_list_skb(struct sk_buff *skb,
1800 struct packet_type **pt,
1801 struct net_device *orig_dev,
1803 struct list_head *ptype_list)
1805 struct packet_type *ptype, *pt_prev = *pt;
1807 list_for_each_entry_rcu(ptype, ptype_list, list) {
1808 if (ptype->type != type)
1811 deliver_skb(skb, pt_prev, orig_dev);
1817 static inline bool skb_loop_sk(struct packet_type *ptype, struct sk_buff *skb)
1819 if (!ptype->af_packet_priv || !skb->sk)
1822 if (ptype->id_match)
1823 return ptype->id_match(ptype, skb->sk);
1824 else if ((struct sock *)ptype->af_packet_priv == skb->sk)
1831 * Support routine. Sends outgoing frames to any network
1832 * taps currently in use.
1835 static void dev_queue_xmit_nit(struct sk_buff *skb, struct net_device *dev)
1837 struct packet_type *ptype;
1838 struct sk_buff *skb2 = NULL;
1839 struct packet_type *pt_prev = NULL;
1840 struct list_head *ptype_list = &ptype_all;
1844 list_for_each_entry_rcu(ptype, ptype_list, list) {
1845 /* Never send packets back to the socket
1846 * they originated from - MvS (miquels@drinkel.ow.org)
1848 if (skb_loop_sk(ptype, skb))
1852 deliver_skb(skb2, pt_prev, skb->dev);
1857 /* need to clone skb, done only once */
1858 skb2 = skb_clone(skb, GFP_ATOMIC);
1862 net_timestamp_set(skb2);
1864 /* skb->nh should be correctly
1865 * set by sender, so that the second statement is
1866 * just protection against buggy protocols.
1868 skb_reset_mac_header(skb2);
1870 if (skb_network_header(skb2) < skb2->data ||
1871 skb_network_header(skb2) > skb_tail_pointer(skb2)) {
1872 net_crit_ratelimited("protocol %04x is buggy, dev %s\n",
1873 ntohs(skb2->protocol),
1875 skb_reset_network_header(skb2);
1878 skb2->transport_header = skb2->network_header;
1879 skb2->pkt_type = PACKET_OUTGOING;
1883 if (ptype_list == &ptype_all) {
1884 ptype_list = &dev->ptype_all;
1889 pt_prev->func(skb2, skb->dev, pt_prev, skb->dev);
1894 * netif_setup_tc - Handle tc mappings on real_num_tx_queues change
1895 * @dev: Network device
1896 * @txq: number of queues available
1898 * If real_num_tx_queues is changed the tc mappings may no longer be
1899 * valid. To resolve this verify the tc mapping remains valid and if
1900 * not NULL the mapping. With no priorities mapping to this
1901 * offset/count pair it will no longer be used. In the worst case TC0
1902 * is invalid nothing can be done so disable priority mappings. If is
1903 * expected that drivers will fix this mapping if they can before
1904 * calling netif_set_real_num_tx_queues.
1906 static void netif_setup_tc(struct net_device *dev, unsigned int txq)
1909 struct netdev_tc_txq *tc = &dev->tc_to_txq[0];
1911 /* If TC0 is invalidated disable TC mapping */
1912 if (tc->offset + tc->count > txq) {
1913 pr_warn("Number of in use tx queues changed invalidating tc mappings. Priority traffic classification disabled!\n");
1918 /* Invalidated prio to tc mappings set to TC0 */
1919 for (i = 1; i < TC_BITMASK + 1; i++) {
1920 int q = netdev_get_prio_tc_map(dev, i);
1922 tc = &dev->tc_to_txq[q];
1923 if (tc->offset + tc->count > txq) {
1924 pr_warn("Number of in use tx queues changed. Priority %i to tc mapping %i is no longer valid. Setting map to 0\n",
1926 netdev_set_prio_tc_map(dev, i, 0);
1932 static DEFINE_MUTEX(xps_map_mutex);
1933 #define xmap_dereference(P) \
1934 rcu_dereference_protected((P), lockdep_is_held(&xps_map_mutex))
1936 static struct xps_map *remove_xps_queue(struct xps_dev_maps *dev_maps,
1939 struct xps_map *map = NULL;
1943 map = xmap_dereference(dev_maps->cpu_map[cpu]);
1945 for (pos = 0; map && pos < map->len; pos++) {
1946 if (map->queues[pos] == index) {
1948 map->queues[pos] = map->queues[--map->len];
1950 RCU_INIT_POINTER(dev_maps->cpu_map[cpu], NULL);
1951 kfree_rcu(map, rcu);
1961 static void netif_reset_xps_queues_gt(struct net_device *dev, u16 index)
1963 struct xps_dev_maps *dev_maps;
1965 bool active = false;
1967 mutex_lock(&xps_map_mutex);
1968 dev_maps = xmap_dereference(dev->xps_maps);
1973 for_each_possible_cpu(cpu) {
1974 for (i = index; i < dev->num_tx_queues; i++) {
1975 if (!remove_xps_queue(dev_maps, cpu, i))
1978 if (i == dev->num_tx_queues)
1983 RCU_INIT_POINTER(dev->xps_maps, NULL);
1984 kfree_rcu(dev_maps, rcu);
1987 for (i = index; i < dev->num_tx_queues; i++)
1988 netdev_queue_numa_node_write(netdev_get_tx_queue(dev, i),
1992 mutex_unlock(&xps_map_mutex);
1995 static struct xps_map *expand_xps_map(struct xps_map *map,
1998 struct xps_map *new_map;
1999 int alloc_len = XPS_MIN_MAP_ALLOC;
2002 for (pos = 0; map && pos < map->len; pos++) {
2003 if (map->queues[pos] != index)
2008 /* Need to add queue to this CPU's existing map */
2010 if (pos < map->alloc_len)
2013 alloc_len = map->alloc_len * 2;
2016 /* Need to allocate new map to store queue on this CPU's map */
2017 new_map = kzalloc_node(XPS_MAP_SIZE(alloc_len), GFP_KERNEL,
2022 for (i = 0; i < pos; i++)
2023 new_map->queues[i] = map->queues[i];
2024 new_map->alloc_len = alloc_len;
2030 int netif_set_xps_queue(struct net_device *dev, const struct cpumask *mask,
2033 struct xps_dev_maps *dev_maps, *new_dev_maps = NULL;
2034 struct xps_map *map, *new_map;
2035 int maps_sz = max_t(unsigned int, XPS_DEV_MAPS_SIZE, L1_CACHE_BYTES);
2036 int cpu, numa_node_id = -2;
2037 bool active = false;
2039 mutex_lock(&xps_map_mutex);
2041 dev_maps = xmap_dereference(dev->xps_maps);
2043 /* allocate memory for queue storage */
2044 for_each_online_cpu(cpu) {
2045 if (!cpumask_test_cpu(cpu, mask))
2049 new_dev_maps = kzalloc(maps_sz, GFP_KERNEL);
2050 if (!new_dev_maps) {
2051 mutex_unlock(&xps_map_mutex);
2055 map = dev_maps ? xmap_dereference(dev_maps->cpu_map[cpu]) :
2058 map = expand_xps_map(map, cpu, index);
2062 RCU_INIT_POINTER(new_dev_maps->cpu_map[cpu], map);
2066 goto out_no_new_maps;
2068 for_each_possible_cpu(cpu) {
2069 if (cpumask_test_cpu(cpu, mask) && cpu_online(cpu)) {
2070 /* add queue to CPU maps */
2073 map = xmap_dereference(new_dev_maps->cpu_map[cpu]);
2074 while ((pos < map->len) && (map->queues[pos] != index))
2077 if (pos == map->len)
2078 map->queues[map->len++] = index;
2080 if (numa_node_id == -2)
2081 numa_node_id = cpu_to_node(cpu);
2082 else if (numa_node_id != cpu_to_node(cpu))
2085 } else if (dev_maps) {
2086 /* fill in the new device map from the old device map */
2087 map = xmap_dereference(dev_maps->cpu_map[cpu]);
2088 RCU_INIT_POINTER(new_dev_maps->cpu_map[cpu], map);
2093 rcu_assign_pointer(dev->xps_maps, new_dev_maps);
2095 /* Cleanup old maps */
2097 for_each_possible_cpu(cpu) {
2098 new_map = xmap_dereference(new_dev_maps->cpu_map[cpu]);
2099 map = xmap_dereference(dev_maps->cpu_map[cpu]);
2100 if (map && map != new_map)
2101 kfree_rcu(map, rcu);
2104 kfree_rcu(dev_maps, rcu);
2107 dev_maps = new_dev_maps;
2111 /* update Tx queue numa node */
2112 netdev_queue_numa_node_write(netdev_get_tx_queue(dev, index),
2113 (numa_node_id >= 0) ? numa_node_id :
2119 /* removes queue from unused CPUs */
2120 for_each_possible_cpu(cpu) {
2121 if (cpumask_test_cpu(cpu, mask) && cpu_online(cpu))
2124 if (remove_xps_queue(dev_maps, cpu, index))
2128 /* free map if not active */
2130 RCU_INIT_POINTER(dev->xps_maps, NULL);
2131 kfree_rcu(dev_maps, rcu);
2135 mutex_unlock(&xps_map_mutex);
2139 /* remove any maps that we added */
2140 for_each_possible_cpu(cpu) {
2141 new_map = xmap_dereference(new_dev_maps->cpu_map[cpu]);
2142 map = dev_maps ? xmap_dereference(dev_maps->cpu_map[cpu]) :
2144 if (new_map && new_map != map)
2148 mutex_unlock(&xps_map_mutex);
2150 kfree(new_dev_maps);
2153 EXPORT_SYMBOL(netif_set_xps_queue);
2157 * Routine to help set real_num_tx_queues. To avoid skbs mapped to queues
2158 * greater then real_num_tx_queues stale skbs on the qdisc must be flushed.
2160 int netif_set_real_num_tx_queues(struct net_device *dev, unsigned int txq)
2164 if (txq < 1 || txq > dev->num_tx_queues)
2167 if (dev->reg_state == NETREG_REGISTERED ||
2168 dev->reg_state == NETREG_UNREGISTERING) {
2171 rc = netdev_queue_update_kobjects(dev, dev->real_num_tx_queues,
2177 netif_setup_tc(dev, txq);
2179 if (txq < dev->real_num_tx_queues) {
2180 qdisc_reset_all_tx_gt(dev, txq);
2182 netif_reset_xps_queues_gt(dev, txq);
2187 dev->real_num_tx_queues = txq;
2190 EXPORT_SYMBOL(netif_set_real_num_tx_queues);
2194 * netif_set_real_num_rx_queues - set actual number of RX queues used
2195 * @dev: Network device
2196 * @rxq: Actual number of RX queues
2198 * This must be called either with the rtnl_lock held or before
2199 * registration of the net device. Returns 0 on success, or a
2200 * negative error code. If called before registration, it always
2203 int netif_set_real_num_rx_queues(struct net_device *dev, unsigned int rxq)
2207 if (rxq < 1 || rxq > dev->num_rx_queues)
2210 if (dev->reg_state == NETREG_REGISTERED) {
2213 rc = net_rx_queue_update_kobjects(dev, dev->real_num_rx_queues,
2219 dev->real_num_rx_queues = rxq;
2222 EXPORT_SYMBOL(netif_set_real_num_rx_queues);
2226 * netif_get_num_default_rss_queues - default number of RSS queues
2228 * This routine should set an upper limit on the number of RSS queues
2229 * used by default by multiqueue devices.
2231 int netif_get_num_default_rss_queues(void)
2233 return min_t(int, DEFAULT_MAX_NUM_RSS_QUEUES, num_online_cpus());
2235 EXPORT_SYMBOL(netif_get_num_default_rss_queues);
2237 static inline void __netif_reschedule(struct Qdisc *q)
2239 struct softnet_data *sd;
2240 unsigned long flags;
2242 local_irq_save(flags);
2243 sd = this_cpu_ptr(&softnet_data);
2244 q->next_sched = NULL;
2245 *sd->output_queue_tailp = q;
2246 sd->output_queue_tailp = &q->next_sched;
2247 raise_softirq_irqoff(NET_TX_SOFTIRQ);
2248 local_irq_restore(flags);
2251 void __netif_schedule(struct Qdisc *q)
2253 if (!test_and_set_bit(__QDISC_STATE_SCHED, &q->state))
2254 __netif_reschedule(q);
2256 EXPORT_SYMBOL(__netif_schedule);
2258 struct dev_kfree_skb_cb {
2259 enum skb_free_reason reason;
2262 static struct dev_kfree_skb_cb *get_kfree_skb_cb(const struct sk_buff *skb)
2264 return (struct dev_kfree_skb_cb *)skb->cb;
2267 void netif_schedule_queue(struct netdev_queue *txq)
2270 if (!(txq->state & QUEUE_STATE_ANY_XOFF)) {
2271 struct Qdisc *q = rcu_dereference(txq->qdisc);
2273 __netif_schedule(q);
2277 EXPORT_SYMBOL(netif_schedule_queue);
2280 * netif_wake_subqueue - allow sending packets on subqueue
2281 * @dev: network device
2282 * @queue_index: sub queue index
2284 * Resume individual transmit queue of a device with multiple transmit queues.
2286 void netif_wake_subqueue(struct net_device *dev, u16 queue_index)
2288 struct netdev_queue *txq = netdev_get_tx_queue(dev, queue_index);
2290 if (test_and_clear_bit(__QUEUE_STATE_DRV_XOFF, &txq->state)) {
2294 q = rcu_dereference(txq->qdisc);
2295 __netif_schedule(q);
2299 EXPORT_SYMBOL(netif_wake_subqueue);
2301 void netif_tx_wake_queue(struct netdev_queue *dev_queue)
2303 if (test_and_clear_bit(__QUEUE_STATE_DRV_XOFF, &dev_queue->state)) {
2307 q = rcu_dereference(dev_queue->qdisc);
2308 __netif_schedule(q);
2312 EXPORT_SYMBOL(netif_tx_wake_queue);
2314 void __dev_kfree_skb_irq(struct sk_buff *skb, enum skb_free_reason reason)
2316 unsigned long flags;
2318 if (likely(atomic_read(&skb->users) == 1)) {
2320 atomic_set(&skb->users, 0);
2321 } else if (likely(!atomic_dec_and_test(&skb->users))) {
2324 get_kfree_skb_cb(skb)->reason = reason;
2325 local_irq_save(flags);
2326 skb->next = __this_cpu_read(softnet_data.completion_queue);
2327 __this_cpu_write(softnet_data.completion_queue, skb);
2328 raise_softirq_irqoff(NET_TX_SOFTIRQ);
2329 local_irq_restore(flags);
2331 EXPORT_SYMBOL(__dev_kfree_skb_irq);
2333 void __dev_kfree_skb_any(struct sk_buff *skb, enum skb_free_reason reason)
2335 if (in_irq() || irqs_disabled())
2336 __dev_kfree_skb_irq(skb, reason);
2340 EXPORT_SYMBOL(__dev_kfree_skb_any);
2344 * netif_device_detach - mark device as removed
2345 * @dev: network device
2347 * Mark device as removed from system and therefore no longer available.
2349 void netif_device_detach(struct net_device *dev)
2351 if (test_and_clear_bit(__LINK_STATE_PRESENT, &dev->state) &&
2352 netif_running(dev)) {
2353 netif_tx_stop_all_queues(dev);
2356 EXPORT_SYMBOL(netif_device_detach);
2359 * netif_device_attach - mark device as attached
2360 * @dev: network device
2362 * Mark device as attached from system and restart if needed.
2364 void netif_device_attach(struct net_device *dev)
2366 if (!test_and_set_bit(__LINK_STATE_PRESENT, &dev->state) &&
2367 netif_running(dev)) {
2368 netif_tx_wake_all_queues(dev);
2369 __netdev_watchdog_up(dev);
2372 EXPORT_SYMBOL(netif_device_attach);
2375 * Returns a Tx hash based on the given packet descriptor a Tx queues' number
2376 * to be used as a distribution range.
2378 u16 __skb_tx_hash(const struct net_device *dev, struct sk_buff *skb,
2379 unsigned int num_tx_queues)
2383 u16 qcount = num_tx_queues;
2385 if (skb_rx_queue_recorded(skb)) {
2386 hash = skb_get_rx_queue(skb);
2387 while (unlikely(hash >= num_tx_queues))
2388 hash -= num_tx_queues;
2393 u8 tc = netdev_get_prio_tc_map(dev, skb->priority);
2394 qoffset = dev->tc_to_txq[tc].offset;
2395 qcount = dev->tc_to_txq[tc].count;
2398 return (u16) reciprocal_scale(skb_get_hash(skb), qcount) + qoffset;
2400 EXPORT_SYMBOL(__skb_tx_hash);
2402 static void skb_warn_bad_offload(const struct sk_buff *skb)
2404 static const netdev_features_t null_features = 0;
2405 struct net_device *dev = skb->dev;
2406 const char *name = "";
2408 if (!net_ratelimit())
2412 if (dev->dev.parent)
2413 name = dev_driver_string(dev->dev.parent);
2415 name = netdev_name(dev);
2417 WARN(1, "%s: caps=(%pNF, %pNF) len=%d data_len=%d gso_size=%d "
2418 "gso_type=%d ip_summed=%d\n",
2419 name, dev ? &dev->features : &null_features,
2420 skb->sk ? &skb->sk->sk_route_caps : &null_features,
2421 skb->len, skb->data_len, skb_shinfo(skb)->gso_size,
2422 skb_shinfo(skb)->gso_type, skb->ip_summed);
2426 * Invalidate hardware checksum when packet is to be mangled, and
2427 * complete checksum manually on outgoing path.
2429 int skb_checksum_help(struct sk_buff *skb)
2432 int ret = 0, offset;
2434 if (skb->ip_summed == CHECKSUM_COMPLETE)
2435 goto out_set_summed;
2437 if (unlikely(skb_shinfo(skb)->gso_size)) {
2438 skb_warn_bad_offload(skb);
2442 /* Before computing a checksum, we should make sure no frag could
2443 * be modified by an external entity : checksum could be wrong.
2445 if (skb_has_shared_frag(skb)) {
2446 ret = __skb_linearize(skb);
2451 offset = skb_checksum_start_offset(skb);
2452 BUG_ON(offset >= skb_headlen(skb));
2453 csum = skb_checksum(skb, offset, skb->len - offset, 0);
2455 offset += skb->csum_offset;
2456 BUG_ON(offset + sizeof(__sum16) > skb_headlen(skb));
2458 if (skb_cloned(skb) &&
2459 !skb_clone_writable(skb, offset + sizeof(__sum16))) {
2460 ret = pskb_expand_head(skb, 0, 0, GFP_ATOMIC);
2465 *(__sum16 *)(skb->data + offset) = csum_fold(csum);
2467 skb->ip_summed = CHECKSUM_NONE;
2471 EXPORT_SYMBOL(skb_checksum_help);
2473 __be16 skb_network_protocol(struct sk_buff *skb, int *depth)
2475 __be16 type = skb->protocol;
2477 /* Tunnel gso handlers can set protocol to ethernet. */
2478 if (type == htons(ETH_P_TEB)) {
2481 if (unlikely(!pskb_may_pull(skb, sizeof(struct ethhdr))))
2484 eth = (struct ethhdr *)skb_mac_header(skb);
2485 type = eth->h_proto;
2488 return __vlan_get_protocol(skb, type, depth);
2492 * skb_mac_gso_segment - mac layer segmentation handler.
2493 * @skb: buffer to segment
2494 * @features: features for the output path (see dev->features)
2496 struct sk_buff *skb_mac_gso_segment(struct sk_buff *skb,
2497 netdev_features_t features)
2499 struct sk_buff *segs = ERR_PTR(-EPROTONOSUPPORT);
2500 struct packet_offload *ptype;
2501 int vlan_depth = skb->mac_len;
2502 __be16 type = skb_network_protocol(skb, &vlan_depth);
2504 if (unlikely(!type))
2505 return ERR_PTR(-EINVAL);
2507 __skb_pull(skb, vlan_depth);
2510 list_for_each_entry_rcu(ptype, &offload_base, list) {
2511 if (ptype->type == type && ptype->callbacks.gso_segment) {
2512 segs = ptype->callbacks.gso_segment(skb, features);
2518 __skb_push(skb, skb->data - skb_mac_header(skb));
2522 EXPORT_SYMBOL(skb_mac_gso_segment);
2525 /* openvswitch calls this on rx path, so we need a different check.
2527 static inline bool skb_needs_check(struct sk_buff *skb, bool tx_path)
2530 return skb->ip_summed != CHECKSUM_PARTIAL;
2532 return skb->ip_summed == CHECKSUM_NONE;
2536 * __skb_gso_segment - Perform segmentation on skb.
2537 * @skb: buffer to segment
2538 * @features: features for the output path (see dev->features)
2539 * @tx_path: whether it is called in TX path
2541 * This function segments the given skb and returns a list of segments.
2543 * It may return NULL if the skb requires no segmentation. This is
2544 * only possible when GSO is used for verifying header integrity.
2546 * Segmentation preserves SKB_SGO_CB_OFFSET bytes of previous skb cb.
2548 struct sk_buff *__skb_gso_segment(struct sk_buff *skb,
2549 netdev_features_t features, bool tx_path)
2551 if (unlikely(skb_needs_check(skb, tx_path))) {
2554 skb_warn_bad_offload(skb);
2556 err = skb_cow_head(skb, 0);
2558 return ERR_PTR(err);
2561 BUILD_BUG_ON(SKB_SGO_CB_OFFSET +
2562 sizeof(*SKB_GSO_CB(skb)) > sizeof(skb->cb));
2564 SKB_GSO_CB(skb)->mac_offset = skb_headroom(skb);
2565 SKB_GSO_CB(skb)->encap_level = 0;
2567 skb_reset_mac_header(skb);
2568 skb_reset_mac_len(skb);
2570 return skb_mac_gso_segment(skb, features);
2572 EXPORT_SYMBOL(__skb_gso_segment);
2574 /* Take action when hardware reception checksum errors are detected. */
2576 void netdev_rx_csum_fault(struct net_device *dev)
2578 if (net_ratelimit()) {
2579 pr_err("%s: hw csum failure\n", dev ? dev->name : "<unknown>");
2583 EXPORT_SYMBOL(netdev_rx_csum_fault);
2586 /* Actually, we should eliminate this check as soon as we know, that:
2587 * 1. IOMMU is present and allows to map all the memory.
2588 * 2. No high memory really exists on this machine.
2591 static int illegal_highdma(struct net_device *dev, struct sk_buff *skb)
2593 #ifdef CONFIG_HIGHMEM
2595 if (!(dev->features & NETIF_F_HIGHDMA)) {
2596 for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
2597 skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
2598 if (PageHighMem(skb_frag_page(frag)))
2603 if (PCI_DMA_BUS_IS_PHYS) {
2604 struct device *pdev = dev->dev.parent;
2608 for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
2609 skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
2610 dma_addr_t addr = page_to_phys(skb_frag_page(frag));
2611 if (!pdev->dma_mask || addr + PAGE_SIZE - 1 > *pdev->dma_mask)
2619 /* If MPLS offload request, verify we are testing hardware MPLS features
2620 * instead of standard features for the netdev.
2622 #if IS_ENABLED(CONFIG_NET_MPLS_GSO)
2623 static netdev_features_t net_mpls_features(struct sk_buff *skb,
2624 netdev_features_t features,
2627 if (eth_p_mpls(type))
2628 features &= skb->dev->mpls_features;
2633 static netdev_features_t net_mpls_features(struct sk_buff *skb,
2634 netdev_features_t features,
2641 static netdev_features_t harmonize_features(struct sk_buff *skb,
2642 netdev_features_t features)
2647 type = skb_network_protocol(skb, &tmp);
2648 features = net_mpls_features(skb, features, type);
2650 if (skb->ip_summed != CHECKSUM_NONE &&
2651 !can_checksum_protocol(features, type)) {
2652 features &= ~NETIF_F_ALL_CSUM;
2653 } else if (illegal_highdma(skb->dev, skb)) {
2654 features &= ~NETIF_F_SG;
2660 netdev_features_t passthru_features_check(struct sk_buff *skb,
2661 struct net_device *dev,
2662 netdev_features_t features)
2666 EXPORT_SYMBOL(passthru_features_check);
2668 static netdev_features_t dflt_features_check(const struct sk_buff *skb,
2669 struct net_device *dev,
2670 netdev_features_t features)
2672 return vlan_features_check(skb, features);
2675 netdev_features_t netif_skb_features(struct sk_buff *skb)
2677 struct net_device *dev = skb->dev;
2678 netdev_features_t features = dev->features;
2679 u16 gso_segs = skb_shinfo(skb)->gso_segs;
2681 if (gso_segs > dev->gso_max_segs || gso_segs < dev->gso_min_segs)
2682 features &= ~NETIF_F_GSO_MASK;
2684 /* If encapsulation offload request, verify we are testing
2685 * hardware encapsulation features instead of standard
2686 * features for the netdev
2688 if (skb->encapsulation)
2689 features &= dev->hw_enc_features;
2691 if (skb_vlan_tagged(skb))
2692 features = netdev_intersect_features(features,
2693 dev->vlan_features |
2694 NETIF_F_HW_VLAN_CTAG_TX |
2695 NETIF_F_HW_VLAN_STAG_TX);
2697 if (dev->netdev_ops->ndo_features_check)
2698 features &= dev->netdev_ops->ndo_features_check(skb, dev,
2701 features &= dflt_features_check(skb, dev, features);
2703 return harmonize_features(skb, features);
2705 EXPORT_SYMBOL(netif_skb_features);
2707 static int xmit_one(struct sk_buff *skb, struct net_device *dev,
2708 struct netdev_queue *txq, bool more)
2713 if (!list_empty(&ptype_all) || !list_empty(&dev->ptype_all))
2714 dev_queue_xmit_nit(skb, dev);
2717 trace_net_dev_start_xmit(skb, dev);
2718 rc = netdev_start_xmit(skb, dev, txq, more);
2719 trace_net_dev_xmit(skb, rc, dev, len);
2724 struct sk_buff *dev_hard_start_xmit(struct sk_buff *first, struct net_device *dev,
2725 struct netdev_queue *txq, int *ret)
2727 struct sk_buff *skb = first;
2728 int rc = NETDEV_TX_OK;
2731 struct sk_buff *next = skb->next;
2734 rc = xmit_one(skb, dev, txq, next != NULL);
2735 if (unlikely(!dev_xmit_complete(rc))) {
2741 if (netif_xmit_stopped(txq) && skb) {
2742 rc = NETDEV_TX_BUSY;
2752 static struct sk_buff *validate_xmit_vlan(struct sk_buff *skb,
2753 netdev_features_t features)
2755 if (skb_vlan_tag_present(skb) &&
2756 !vlan_hw_offload_capable(features, skb->vlan_proto))
2757 skb = __vlan_hwaccel_push_inside(skb);
2761 static struct sk_buff *validate_xmit_skb(struct sk_buff *skb, struct net_device *dev)
2763 netdev_features_t features;
2768 features = netif_skb_features(skb);
2769 skb = validate_xmit_vlan(skb, features);
2773 if (netif_needs_gso(skb, features)) {
2774 struct sk_buff *segs;
2776 segs = skb_gso_segment(skb, features);
2784 if (skb_needs_linearize(skb, features) &&
2785 __skb_linearize(skb))
2788 /* If packet is not checksummed and device does not
2789 * support checksumming for this protocol, complete
2790 * checksumming here.
2792 if (skb->ip_summed == CHECKSUM_PARTIAL) {
2793 if (skb->encapsulation)
2794 skb_set_inner_transport_header(skb,
2795 skb_checksum_start_offset(skb));
2797 skb_set_transport_header(skb,
2798 skb_checksum_start_offset(skb));
2799 if (!(features & NETIF_F_ALL_CSUM) &&
2800 skb_checksum_help(skb))
2813 struct sk_buff *validate_xmit_skb_list(struct sk_buff *skb, struct net_device *dev)
2815 struct sk_buff *next, *head = NULL, *tail;
2817 for (; skb != NULL; skb = next) {
2821 /* in case skb wont be segmented, point to itself */
2824 skb = validate_xmit_skb(skb, dev);
2832 /* If skb was segmented, skb->prev points to
2833 * the last segment. If not, it still contains skb.
2840 static void qdisc_pkt_len_init(struct sk_buff *skb)
2842 const struct skb_shared_info *shinfo = skb_shinfo(skb);
2844 qdisc_skb_cb(skb)->pkt_len = skb->len;
2846 /* To get more precise estimation of bytes sent on wire,
2847 * we add to pkt_len the headers size of all segments
2849 if (shinfo->gso_size) {
2850 unsigned int hdr_len;
2851 u16 gso_segs = shinfo->gso_segs;
2853 /* mac layer + network layer */
2854 hdr_len = skb_transport_header(skb) - skb_mac_header(skb);
2856 /* + transport layer */
2857 if (likely(shinfo->gso_type & (SKB_GSO_TCPV4 | SKB_GSO_TCPV6)))
2858 hdr_len += tcp_hdrlen(skb);
2860 hdr_len += sizeof(struct udphdr);
2862 if (shinfo->gso_type & SKB_GSO_DODGY)
2863 gso_segs = DIV_ROUND_UP(skb->len - hdr_len,
2866 qdisc_skb_cb(skb)->pkt_len += (gso_segs - 1) * hdr_len;
2870 static inline int __dev_xmit_skb(struct sk_buff *skb, struct Qdisc *q,
2871 struct net_device *dev,
2872 struct netdev_queue *txq)
2874 spinlock_t *root_lock = qdisc_lock(q);
2878 qdisc_pkt_len_init(skb);
2879 qdisc_calculate_pkt_len(skb, q);
2881 * Heuristic to force contended enqueues to serialize on a
2882 * separate lock before trying to get qdisc main lock.
2883 * This permits __QDISC___STATE_RUNNING owner to get the lock more
2884 * often and dequeue packets faster.
2886 contended = qdisc_is_running(q);
2887 if (unlikely(contended))
2888 spin_lock(&q->busylock);
2890 spin_lock(root_lock);
2891 if (unlikely(test_bit(__QDISC_STATE_DEACTIVATED, &q->state))) {
2894 } else if ((q->flags & TCQ_F_CAN_BYPASS) && !qdisc_qlen(q) &&
2895 qdisc_run_begin(q)) {
2897 * This is a work-conserving queue; there are no old skbs
2898 * waiting to be sent out; and the qdisc is not running -
2899 * xmit the skb directly.
2902 qdisc_bstats_update(q, skb);
2904 if (sch_direct_xmit(skb, q, dev, txq, root_lock, true)) {
2905 if (unlikely(contended)) {
2906 spin_unlock(&q->busylock);
2913 rc = NET_XMIT_SUCCESS;
2915 rc = q->enqueue(skb, q) & NET_XMIT_MASK;
2916 if (qdisc_run_begin(q)) {
2917 if (unlikely(contended)) {
2918 spin_unlock(&q->busylock);
2924 spin_unlock(root_lock);
2925 if (unlikely(contended))
2926 spin_unlock(&q->busylock);
2930 #if IS_ENABLED(CONFIG_CGROUP_NET_PRIO)
2931 static void skb_update_prio(struct sk_buff *skb)
2933 struct netprio_map *map = rcu_dereference_bh(skb->dev->priomap);
2935 if (!skb->priority && skb->sk && map) {
2936 unsigned int prioidx = skb->sk->sk_cgrp_prioidx;
2938 if (prioidx < map->priomap_len)
2939 skb->priority = map->priomap[prioidx];
2943 #define skb_update_prio(skb)
2946 DEFINE_PER_CPU(int, xmit_recursion);
2947 EXPORT_SYMBOL(xmit_recursion);
2949 #define RECURSION_LIMIT 10
2952 * dev_loopback_xmit - loop back @skb
2953 * @net: network namespace this loopback is happening in
2954 * @sk: sk needed to be a netfilter okfn
2955 * @skb: buffer to transmit
2957 int dev_loopback_xmit(struct net *net, struct sock *sk, struct sk_buff *skb)
2959 skb_reset_mac_header(skb);
2960 __skb_pull(skb, skb_network_offset(skb));
2961 skb->pkt_type = PACKET_LOOPBACK;
2962 skb->ip_summed = CHECKSUM_UNNECESSARY;
2963 WARN_ON(!skb_dst(skb));
2968 EXPORT_SYMBOL(dev_loopback_xmit);
2970 static inline int get_xps_queue(struct net_device *dev, struct sk_buff *skb)
2973 struct xps_dev_maps *dev_maps;
2974 struct xps_map *map;
2975 int queue_index = -1;
2978 dev_maps = rcu_dereference(dev->xps_maps);
2980 map = rcu_dereference(
2981 dev_maps->cpu_map[skb->sender_cpu - 1]);
2984 queue_index = map->queues[0];
2986 queue_index = map->queues[reciprocal_scale(skb_get_hash(skb),
2988 if (unlikely(queue_index >= dev->real_num_tx_queues))
3000 static u16 __netdev_pick_tx(struct net_device *dev, struct sk_buff *skb)
3002 struct sock *sk = skb->sk;
3003 int queue_index = sk_tx_queue_get(sk);
3005 if (queue_index < 0 || skb->ooo_okay ||
3006 queue_index >= dev->real_num_tx_queues) {
3007 int new_index = get_xps_queue(dev, skb);
3009 new_index = skb_tx_hash(dev, skb);
3011 if (queue_index != new_index && sk &&
3013 rcu_access_pointer(sk->sk_dst_cache))
3014 sk_tx_queue_set(sk, new_index);
3016 queue_index = new_index;
3022 struct netdev_queue *netdev_pick_tx(struct net_device *dev,
3023 struct sk_buff *skb,
3026 int queue_index = 0;
3029 if (skb->sender_cpu == 0)
3030 skb->sender_cpu = raw_smp_processor_id() + 1;
3033 if (dev->real_num_tx_queues != 1) {
3034 const struct net_device_ops *ops = dev->netdev_ops;
3035 if (ops->ndo_select_queue)
3036 queue_index = ops->ndo_select_queue(dev, skb, accel_priv,
3039 queue_index = __netdev_pick_tx(dev, skb);
3042 queue_index = netdev_cap_txqueue(dev, queue_index);
3045 skb_set_queue_mapping(skb, queue_index);
3046 return netdev_get_tx_queue(dev, queue_index);
3050 * __dev_queue_xmit - transmit a buffer
3051 * @skb: buffer to transmit
3052 * @accel_priv: private data used for L2 forwarding offload
3054 * Queue a buffer for transmission to a network device. The caller must
3055 * have set the device and priority and built the buffer before calling
3056 * this function. The function can be called from an interrupt.
3058 * A negative errno code is returned on a failure. A success does not
3059 * guarantee the frame will be transmitted as it may be dropped due
3060 * to congestion or traffic shaping.
3062 * -----------------------------------------------------------------------------------
3063 * I notice this method can also return errors from the queue disciplines,
3064 * including NET_XMIT_DROP, which is a positive value. So, errors can also
3067 * Regardless of the return value, the skb is consumed, so it is currently
3068 * difficult to retry a send to this method. (You can bump the ref count
3069 * before sending to hold a reference for retry if you are careful.)
3071 * When calling this method, interrupts MUST be enabled. This is because
3072 * the BH enable code must have IRQs enabled so that it will not deadlock.
3075 static int __dev_queue_xmit(struct sk_buff *skb, void *accel_priv)
3077 struct net_device *dev = skb->dev;
3078 struct netdev_queue *txq;
3082 skb_reset_mac_header(skb);
3084 if (unlikely(skb_shinfo(skb)->tx_flags & SKBTX_SCHED_TSTAMP))
3085 __skb_tstamp_tx(skb, NULL, skb->sk, SCM_TSTAMP_SCHED);
3087 /* Disable soft irqs for various locks below. Also
3088 * stops preemption for RCU.
3092 skb_update_prio(skb);
3094 /* If device/qdisc don't need skb->dst, release it right now while
3095 * its hot in this cpu cache.
3097 if (dev->priv_flags & IFF_XMIT_DST_RELEASE)
3102 #ifdef CONFIG_NET_SWITCHDEV
3103 /* Don't forward if offload device already forwarded */
3104 if (skb->offload_fwd_mark &&
3105 skb->offload_fwd_mark == dev->offload_fwd_mark) {
3107 rc = NET_XMIT_SUCCESS;
3112 txq = netdev_pick_tx(dev, skb, accel_priv);
3113 q = rcu_dereference_bh(txq->qdisc);
3115 #ifdef CONFIG_NET_CLS_ACT
3116 skb->tc_verd = SET_TC_AT(skb->tc_verd, AT_EGRESS);
3118 trace_net_dev_queue(skb);
3120 rc = __dev_xmit_skb(skb, q, dev, txq);
3124 /* The device has no queue. Common case for software devices:
3125 loopback, all the sorts of tunnels...
3127 Really, it is unlikely that netif_tx_lock protection is necessary
3128 here. (f.e. loopback and IP tunnels are clean ignoring statistics
3130 However, it is possible, that they rely on protection
3133 Check this and shot the lock. It is not prone from deadlocks.
3134 Either shot noqueue qdisc, it is even simpler 8)
3136 if (dev->flags & IFF_UP) {
3137 int cpu = smp_processor_id(); /* ok because BHs are off */
3139 if (txq->xmit_lock_owner != cpu) {
3141 if (__this_cpu_read(xmit_recursion) > RECURSION_LIMIT)
3142 goto recursion_alert;
3144 skb = validate_xmit_skb(skb, dev);
3148 HARD_TX_LOCK(dev, txq, cpu);
3150 if (!netif_xmit_stopped(txq)) {
3151 __this_cpu_inc(xmit_recursion);
3152 skb = dev_hard_start_xmit(skb, dev, txq, &rc);
3153 __this_cpu_dec(xmit_recursion);
3154 if (dev_xmit_complete(rc)) {
3155 HARD_TX_UNLOCK(dev, txq);
3159 HARD_TX_UNLOCK(dev, txq);
3160 net_crit_ratelimited("Virtual device %s asks to queue packet!\n",
3163 /* Recursion is detected! It is possible,
3167 net_crit_ratelimited("Dead loop on virtual device %s, fix it urgently!\n",
3174 rcu_read_unlock_bh();
3176 atomic_long_inc(&dev->tx_dropped);
3177 kfree_skb_list(skb);
3180 rcu_read_unlock_bh();
3184 int dev_queue_xmit(struct sk_buff *skb)
3186 return __dev_queue_xmit(skb, NULL);
3188 EXPORT_SYMBOL(dev_queue_xmit);
3190 int dev_queue_xmit_accel(struct sk_buff *skb, void *accel_priv)
3192 return __dev_queue_xmit(skb, accel_priv);
3194 EXPORT_SYMBOL(dev_queue_xmit_accel);
3197 /*=======================================================================
3199 =======================================================================*/
3201 int netdev_max_backlog __read_mostly = 1000;
3202 EXPORT_SYMBOL(netdev_max_backlog);
3204 int netdev_tstamp_prequeue __read_mostly = 1;
3205 int netdev_budget __read_mostly = 300;
3206 int weight_p __read_mostly = 64; /* old backlog weight */
3208 /* Called with irq disabled */
3209 static inline void ____napi_schedule(struct softnet_data *sd,
3210 struct napi_struct *napi)
3212 list_add_tail(&napi->poll_list, &sd->poll_list);
3213 __raise_softirq_irqoff(NET_RX_SOFTIRQ);
3218 /* One global table that all flow-based protocols share. */
3219 struct rps_sock_flow_table __rcu *rps_sock_flow_table __read_mostly;
3220 EXPORT_SYMBOL(rps_sock_flow_table);
3221 u32 rps_cpu_mask __read_mostly;
3222 EXPORT_SYMBOL(rps_cpu_mask);
3224 struct static_key rps_needed __read_mostly;
3226 static struct rps_dev_flow *
3227 set_rps_cpu(struct net_device *dev, struct sk_buff *skb,
3228 struct rps_dev_flow *rflow, u16 next_cpu)
3230 if (next_cpu < nr_cpu_ids) {
3231 #ifdef CONFIG_RFS_ACCEL
3232 struct netdev_rx_queue *rxqueue;
3233 struct rps_dev_flow_table *flow_table;
3234 struct rps_dev_flow *old_rflow;
3239 /* Should we steer this flow to a different hardware queue? */
3240 if (!skb_rx_queue_recorded(skb) || !dev->rx_cpu_rmap ||
3241 !(dev->features & NETIF_F_NTUPLE))
3243 rxq_index = cpu_rmap_lookup_index(dev->rx_cpu_rmap, next_cpu);
3244 if (rxq_index == skb_get_rx_queue(skb))
3247 rxqueue = dev->_rx + rxq_index;
3248 flow_table = rcu_dereference(rxqueue->rps_flow_table);
3251 flow_id = skb_get_hash(skb) & flow_table->mask;
3252 rc = dev->netdev_ops->ndo_rx_flow_steer(dev, skb,
3253 rxq_index, flow_id);
3257 rflow = &flow_table->flows[flow_id];
3259 if (old_rflow->filter == rflow->filter)
3260 old_rflow->filter = RPS_NO_FILTER;
3264 per_cpu(softnet_data, next_cpu).input_queue_head;
3267 rflow->cpu = next_cpu;
3272 * get_rps_cpu is called from netif_receive_skb and returns the target
3273 * CPU from the RPS map of the receiving queue for a given skb.
3274 * rcu_read_lock must be held on entry.
3276 static int get_rps_cpu(struct net_device *dev, struct sk_buff *skb,
3277 struct rps_dev_flow **rflowp)
3279 const struct rps_sock_flow_table *sock_flow_table;
3280 struct netdev_rx_queue *rxqueue = dev->_rx;
3281 struct rps_dev_flow_table *flow_table;
3282 struct rps_map *map;
3287 if (skb_rx_queue_recorded(skb)) {
3288 u16 index = skb_get_rx_queue(skb);
3290 if (unlikely(index >= dev->real_num_rx_queues)) {
3291 WARN_ONCE(dev->real_num_rx_queues > 1,
3292 "%s received packet on queue %u, but number "
3293 "of RX queues is %u\n",
3294 dev->name, index, dev->real_num_rx_queues);
3300 /* Avoid computing hash if RFS/RPS is not active for this rxqueue */
3302 flow_table = rcu_dereference(rxqueue->rps_flow_table);
3303 map = rcu_dereference(rxqueue->rps_map);
3304 if (!flow_table && !map)
3307 skb_reset_network_header(skb);
3308 hash = skb_get_hash(skb);
3312 sock_flow_table = rcu_dereference(rps_sock_flow_table);
3313 if (flow_table && sock_flow_table) {
3314 struct rps_dev_flow *rflow;
3318 /* First check into global flow table if there is a match */
3319 ident = sock_flow_table->ents[hash & sock_flow_table->mask];
3320 if ((ident ^ hash) & ~rps_cpu_mask)
3323 next_cpu = ident & rps_cpu_mask;
3325 /* OK, now we know there is a match,
3326 * we can look at the local (per receive queue) flow table
3328 rflow = &flow_table->flows[hash & flow_table->mask];
3332 * If the desired CPU (where last recvmsg was done) is
3333 * different from current CPU (one in the rx-queue flow
3334 * table entry), switch if one of the following holds:
3335 * - Current CPU is unset (>= nr_cpu_ids).
3336 * - Current CPU is offline.
3337 * - The current CPU's queue tail has advanced beyond the
3338 * last packet that was enqueued using this table entry.
3339 * This guarantees that all previous packets for the flow
3340 * have been dequeued, thus preserving in order delivery.
3342 if (unlikely(tcpu != next_cpu) &&
3343 (tcpu >= nr_cpu_ids || !cpu_online(tcpu) ||
3344 ((int)(per_cpu(softnet_data, tcpu).input_queue_head -
3345 rflow->last_qtail)) >= 0)) {
3347 rflow = set_rps_cpu(dev, skb, rflow, next_cpu);
3350 if (tcpu < nr_cpu_ids && cpu_online(tcpu)) {
3360 tcpu = map->cpus[reciprocal_scale(hash, map->len)];
3361 if (cpu_online(tcpu)) {
3371 #ifdef CONFIG_RFS_ACCEL
3374 * rps_may_expire_flow - check whether an RFS hardware filter may be removed
3375 * @dev: Device on which the filter was set
3376 * @rxq_index: RX queue index
3377 * @flow_id: Flow ID passed to ndo_rx_flow_steer()
3378 * @filter_id: Filter ID returned by ndo_rx_flow_steer()
3380 * Drivers that implement ndo_rx_flow_steer() should periodically call
3381 * this function for each installed filter and remove the filters for
3382 * which it returns %true.
3384 bool rps_may_expire_flow(struct net_device *dev, u16 rxq_index,
3385 u32 flow_id, u16 filter_id)
3387 struct netdev_rx_queue *rxqueue = dev->_rx + rxq_index;
3388 struct rps_dev_flow_table *flow_table;
3389 struct rps_dev_flow *rflow;
3394 flow_table = rcu_dereference(rxqueue->rps_flow_table);
3395 if (flow_table && flow_id <= flow_table->mask) {
3396 rflow = &flow_table->flows[flow_id];
3397 cpu = ACCESS_ONCE(rflow->cpu);
3398 if (rflow->filter == filter_id && cpu < nr_cpu_ids &&
3399 ((int)(per_cpu(softnet_data, cpu).input_queue_head -
3400 rflow->last_qtail) <
3401 (int)(10 * flow_table->mask)))
3407 EXPORT_SYMBOL(rps_may_expire_flow);
3409 #endif /* CONFIG_RFS_ACCEL */
3411 /* Called from hardirq (IPI) context */
3412 static void rps_trigger_softirq(void *data)
3414 struct softnet_data *sd = data;
3416 ____napi_schedule(sd, &sd->backlog);
3420 #endif /* CONFIG_RPS */
3423 * Check if this softnet_data structure is another cpu one
3424 * If yes, queue it to our IPI list and return 1
3427 static int rps_ipi_queued(struct softnet_data *sd)
3430 struct softnet_data *mysd = this_cpu_ptr(&softnet_data);
3433 sd->rps_ipi_next = mysd->rps_ipi_list;
3434 mysd->rps_ipi_list = sd;
3436 __raise_softirq_irqoff(NET_RX_SOFTIRQ);
3439 #endif /* CONFIG_RPS */
3443 #ifdef CONFIG_NET_FLOW_LIMIT
3444 int netdev_flow_limit_table_len __read_mostly = (1 << 12);
3447 static bool skb_flow_limit(struct sk_buff *skb, unsigned int qlen)
3449 #ifdef CONFIG_NET_FLOW_LIMIT
3450 struct sd_flow_limit *fl;
3451 struct softnet_data *sd;
3452 unsigned int old_flow, new_flow;
3454 if (qlen < (netdev_max_backlog >> 1))
3457 sd = this_cpu_ptr(&softnet_data);
3460 fl = rcu_dereference(sd->flow_limit);
3462 new_flow = skb_get_hash(skb) & (fl->num_buckets - 1);
3463 old_flow = fl->history[fl->history_head];
3464 fl->history[fl->history_head] = new_flow;
3467 fl->history_head &= FLOW_LIMIT_HISTORY - 1;
3469 if (likely(fl->buckets[old_flow]))
3470 fl->buckets[old_flow]--;
3472 if (++fl->buckets[new_flow] > (FLOW_LIMIT_HISTORY >> 1)) {
3484 * enqueue_to_backlog is called to queue an skb to a per CPU backlog
3485 * queue (may be a remote CPU queue).
3487 static int enqueue_to_backlog(struct sk_buff *skb, int cpu,
3488 unsigned int *qtail)
3490 struct softnet_data *sd;
3491 unsigned long flags;
3494 sd = &per_cpu(softnet_data, cpu);
3496 local_irq_save(flags);
3499 if (!netif_running(skb->dev))
3501 qlen = skb_queue_len(&sd->input_pkt_queue);
3502 if (qlen <= netdev_max_backlog && !skb_flow_limit(skb, qlen)) {
3505 __skb_queue_tail(&sd->input_pkt_queue, skb);
3506 input_queue_tail_incr_save(sd, qtail);
3508 local_irq_restore(flags);
3509 return NET_RX_SUCCESS;
3512 /* Schedule NAPI for backlog device
3513 * We can use non atomic operation since we own the queue lock
3515 if (!__test_and_set_bit(NAPI_STATE_SCHED, &sd->backlog.state)) {
3516 if (!rps_ipi_queued(sd))
3517 ____napi_schedule(sd, &sd->backlog);
3526 local_irq_restore(flags);
3528 atomic_long_inc(&skb->dev->rx_dropped);
3533 static int netif_rx_internal(struct sk_buff *skb)
3537 net_timestamp_check(netdev_tstamp_prequeue, skb);
3539 trace_netif_rx(skb);
3541 if (static_key_false(&rps_needed)) {
3542 struct rps_dev_flow voidflow, *rflow = &voidflow;
3548 cpu = get_rps_cpu(skb->dev, skb, &rflow);
3550 cpu = smp_processor_id();
3552 ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail);
3560 ret = enqueue_to_backlog(skb, get_cpu(), &qtail);
3567 * netif_rx - post buffer to the network code
3568 * @skb: buffer to post
3570 * This function receives a packet from a device driver and queues it for
3571 * the upper (protocol) levels to process. It always succeeds. The buffer
3572 * may be dropped during processing for congestion control or by the
3576 * NET_RX_SUCCESS (no congestion)
3577 * NET_RX_DROP (packet was dropped)
3581 int netif_rx(struct sk_buff *skb)
3583 trace_netif_rx_entry(skb);
3585 return netif_rx_internal(skb);
3587 EXPORT_SYMBOL(netif_rx);
3589 int netif_rx_ni(struct sk_buff *skb)
3593 trace_netif_rx_ni_entry(skb);
3596 err = netif_rx_internal(skb);
3597 if (local_softirq_pending())
3603 EXPORT_SYMBOL(netif_rx_ni);
3605 static void net_tx_action(struct softirq_action *h)
3607 struct softnet_data *sd = this_cpu_ptr(&softnet_data);
3609 if (sd->completion_queue) {
3610 struct sk_buff *clist;
3612 local_irq_disable();
3613 clist = sd->completion_queue;
3614 sd->completion_queue = NULL;
3618 struct sk_buff *skb = clist;
3619 clist = clist->next;
3621 WARN_ON(atomic_read(&skb->users));
3622 if (likely(get_kfree_skb_cb(skb)->reason == SKB_REASON_CONSUMED))
3623 trace_consume_skb(skb);
3625 trace_kfree_skb(skb, net_tx_action);
3630 if (sd->output_queue) {
3633 local_irq_disable();
3634 head = sd->output_queue;
3635 sd->output_queue = NULL;
3636 sd->output_queue_tailp = &sd->output_queue;
3640 struct Qdisc *q = head;
3641 spinlock_t *root_lock;
3643 head = head->next_sched;
3645 root_lock = qdisc_lock(q);
3646 if (spin_trylock(root_lock)) {
3647 smp_mb__before_atomic();
3648 clear_bit(__QDISC_STATE_SCHED,
3651 spin_unlock(root_lock);
3653 if (!test_bit(__QDISC_STATE_DEACTIVATED,
3655 __netif_reschedule(q);
3657 smp_mb__before_atomic();
3658 clear_bit(__QDISC_STATE_SCHED,
3666 #if (defined(CONFIG_BRIDGE) || defined(CONFIG_BRIDGE_MODULE)) && \
3667 (defined(CONFIG_ATM_LANE) || defined(CONFIG_ATM_LANE_MODULE))
3668 /* This hook is defined here for ATM LANE */
3669 int (*br_fdb_test_addr_hook)(struct net_device *dev,
3670 unsigned char *addr) __read_mostly;
3671 EXPORT_SYMBOL_GPL(br_fdb_test_addr_hook);
3674 static inline struct sk_buff *handle_ing(struct sk_buff *skb,
3675 struct packet_type **pt_prev,
3676 int *ret, struct net_device *orig_dev)
3678 #ifdef CONFIG_NET_CLS_ACT
3679 struct tcf_proto *cl = rcu_dereference_bh(skb->dev->ingress_cl_list);
3680 struct tcf_result cl_res;
3682 /* If there's at least one ingress present somewhere (so
3683 * we get here via enabled static key), remaining devices
3684 * that are not configured with an ingress qdisc will bail
3690 *ret = deliver_skb(skb, *pt_prev, orig_dev);
3694 qdisc_skb_cb(skb)->pkt_len = skb->len;
3695 skb->tc_verd = SET_TC_AT(skb->tc_verd, AT_INGRESS);
3696 qdisc_bstats_cpu_update(cl->q, skb);
3698 switch (tc_classify(skb, cl, &cl_res, false)) {
3700 case TC_ACT_RECLASSIFY:
3701 skb->tc_index = TC_H_MIN(cl_res.classid);
3704 qdisc_qstats_cpu_drop(cl->q);
3709 case TC_ACT_REDIRECT:
3710 /* skb_mac_header check was done by cls/act_bpf, so
3711 * we can safely push the L2 header back before
3712 * redirecting to another netdev
3714 __skb_push(skb, skb->mac_len);
3715 skb_do_redirect(skb);
3720 #endif /* CONFIG_NET_CLS_ACT */
3725 * netdev_is_rx_handler_busy - check if receive handler is registered
3726 * @dev: device to check
3728 * Check if a receive handler is already registered for a given device.
3729 * Return true if there one.
3731 * The caller must hold the rtnl_mutex.
3733 bool netdev_is_rx_handler_busy(struct net_device *dev)
3736 return dev && rtnl_dereference(dev->rx_handler);
3738 EXPORT_SYMBOL_GPL(netdev_is_rx_handler_busy);
3741 * netdev_rx_handler_register - register receive handler
3742 * @dev: device to register a handler for
3743 * @rx_handler: receive handler to register
3744 * @rx_handler_data: data pointer that is used by rx handler
3746 * Register a receive handler for a device. This handler will then be
3747 * called from __netif_receive_skb. A negative errno code is returned
3750 * The caller must hold the rtnl_mutex.
3752 * For a general description of rx_handler, see enum rx_handler_result.
3754 int netdev_rx_handler_register(struct net_device *dev,
3755 rx_handler_func_t *rx_handler,
3756 void *rx_handler_data)
3760 if (dev->rx_handler)
3763 /* Note: rx_handler_data must be set before rx_handler */
3764 rcu_assign_pointer(dev->rx_handler_data, rx_handler_data);
3765 rcu_assign_pointer(dev->rx_handler, rx_handler);
3769 EXPORT_SYMBOL_GPL(netdev_rx_handler_register);
3772 * netdev_rx_handler_unregister - unregister receive handler
3773 * @dev: device to unregister a handler from
3775 * Unregister a receive handler from a device.
3777 * The caller must hold the rtnl_mutex.
3779 void netdev_rx_handler_unregister(struct net_device *dev)
3783 RCU_INIT_POINTER(dev->rx_handler, NULL);
3784 /* a reader seeing a non NULL rx_handler in a rcu_read_lock()
3785 * section has a guarantee to see a non NULL rx_handler_data
3789 RCU_INIT_POINTER(dev->rx_handler_data, NULL);
3791 EXPORT_SYMBOL_GPL(netdev_rx_handler_unregister);
3794 * Limit the use of PFMEMALLOC reserves to those protocols that implement
3795 * the special handling of PFMEMALLOC skbs.
3797 static bool skb_pfmemalloc_protocol(struct sk_buff *skb)
3799 switch (skb->protocol) {
3800 case htons(ETH_P_ARP):
3801 case htons(ETH_P_IP):
3802 case htons(ETH_P_IPV6):
3803 case htons(ETH_P_8021Q):
3804 case htons(ETH_P_8021AD):
3811 static inline int nf_ingress(struct sk_buff *skb, struct packet_type **pt_prev,
3812 int *ret, struct net_device *orig_dev)
3814 #ifdef CONFIG_NETFILTER_INGRESS
3815 if (nf_hook_ingress_active(skb)) {
3817 *ret = deliver_skb(skb, *pt_prev, orig_dev);
3821 return nf_hook_ingress(skb);
3823 #endif /* CONFIG_NETFILTER_INGRESS */
3827 static int __netif_receive_skb_core(struct sk_buff *skb, bool pfmemalloc)
3829 struct packet_type *ptype, *pt_prev;
3830 rx_handler_func_t *rx_handler;
3831 struct net_device *orig_dev;
3832 bool deliver_exact = false;
3833 int ret = NET_RX_DROP;
3836 net_timestamp_check(!netdev_tstamp_prequeue, skb);
3838 trace_netif_receive_skb(skb);
3840 orig_dev = skb->dev;
3842 skb_reset_network_header(skb);
3843 if (!skb_transport_header_was_set(skb))
3844 skb_reset_transport_header(skb);
3845 skb_reset_mac_len(skb);
3850 skb->skb_iif = skb->dev->ifindex;
3852 __this_cpu_inc(softnet_data.processed);
3854 if (skb->protocol == cpu_to_be16(ETH_P_8021Q) ||
3855 skb->protocol == cpu_to_be16(ETH_P_8021AD)) {
3856 skb = skb_vlan_untag(skb);
3861 #ifdef CONFIG_NET_CLS_ACT
3862 if (skb->tc_verd & TC_NCLS) {
3863 skb->tc_verd = CLR_TC_NCLS(skb->tc_verd);
3871 list_for_each_entry_rcu(ptype, &ptype_all, list) {
3873 ret = deliver_skb(skb, pt_prev, orig_dev);
3877 list_for_each_entry_rcu(ptype, &skb->dev->ptype_all, list) {
3879 ret = deliver_skb(skb, pt_prev, orig_dev);
3884 #ifdef CONFIG_NET_INGRESS
3885 if (static_key_false(&ingress_needed)) {
3886 skb = handle_ing(skb, &pt_prev, &ret, orig_dev);
3890 if (nf_ingress(skb, &pt_prev, &ret, orig_dev) < 0)
3894 #ifdef CONFIG_NET_CLS_ACT
3898 if (pfmemalloc && !skb_pfmemalloc_protocol(skb))
3901 if (skb_vlan_tag_present(skb)) {
3903 ret = deliver_skb(skb, pt_prev, orig_dev);
3906 if (vlan_do_receive(&skb))
3908 else if (unlikely(!skb))
3912 rx_handler = rcu_dereference(skb->dev->rx_handler);
3915 ret = deliver_skb(skb, pt_prev, orig_dev);
3918 switch (rx_handler(&skb)) {
3919 case RX_HANDLER_CONSUMED:
3920 ret = NET_RX_SUCCESS;
3922 case RX_HANDLER_ANOTHER:
3924 case RX_HANDLER_EXACT:
3925 deliver_exact = true;
3926 case RX_HANDLER_PASS:
3933 if (unlikely(skb_vlan_tag_present(skb))) {
3934 if (skb_vlan_tag_get_id(skb))
3935 skb->pkt_type = PACKET_OTHERHOST;
3936 /* Note: we might in the future use prio bits
3937 * and set skb->priority like in vlan_do_receive()
3938 * For the time being, just ignore Priority Code Point
3943 type = skb->protocol;
3945 /* deliver only exact match when indicated */
3946 if (likely(!deliver_exact)) {
3947 deliver_ptype_list_skb(skb, &pt_prev, orig_dev, type,
3948 &ptype_base[ntohs(type) &
3952 deliver_ptype_list_skb(skb, &pt_prev, orig_dev, type,
3953 &orig_dev->ptype_specific);
3955 if (unlikely(skb->dev != orig_dev)) {
3956 deliver_ptype_list_skb(skb, &pt_prev, orig_dev, type,
3957 &skb->dev->ptype_specific);
3961 if (unlikely(skb_orphan_frags(skb, GFP_ATOMIC)))
3964 ret = pt_prev->func(skb, skb->dev, pt_prev, orig_dev);
3967 atomic_long_inc(&skb->dev->rx_dropped);
3969 /* Jamal, now you will not able to escape explaining
3970 * me how you were going to use this. :-)
3979 static int __netif_receive_skb(struct sk_buff *skb)
3983 if (sk_memalloc_socks() && skb_pfmemalloc(skb)) {
3984 unsigned long pflags = current->flags;
3987 * PFMEMALLOC skbs are special, they should
3988 * - be delivered to SOCK_MEMALLOC sockets only
3989 * - stay away from userspace
3990 * - have bounded memory usage
3992 * Use PF_MEMALLOC as this saves us from propagating the allocation
3993 * context down to all allocation sites.
3995 current->flags |= PF_MEMALLOC;
3996 ret = __netif_receive_skb_core(skb, true);
3997 tsk_restore_flags(current, pflags, PF_MEMALLOC);
3999 ret = __netif_receive_skb_core(skb, false);
4004 static int netif_receive_skb_internal(struct sk_buff *skb)
4008 net_timestamp_check(netdev_tstamp_prequeue, skb);
4010 if (skb_defer_rx_timestamp(skb))
4011 return NET_RX_SUCCESS;
4016 if (static_key_false(&rps_needed)) {
4017 struct rps_dev_flow voidflow, *rflow = &voidflow;
4018 int cpu = get_rps_cpu(skb->dev, skb, &rflow);
4021 ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail);
4027 ret = __netif_receive_skb(skb);
4033 * netif_receive_skb - process receive buffer from network
4034 * @skb: buffer to process
4036 * netif_receive_skb() is the main receive data processing function.
4037 * It always succeeds. The buffer may be dropped during processing
4038 * for congestion control or by the protocol layers.
4040 * This function may only be called from softirq context and interrupts
4041 * should be enabled.
4043 * Return values (usually ignored):
4044 * NET_RX_SUCCESS: no congestion
4045 * NET_RX_DROP: packet was dropped
4047 int netif_receive_skb(struct sk_buff *skb)
4049 trace_netif_receive_skb_entry(skb);
4051 return netif_receive_skb_internal(skb);
4053 EXPORT_SYMBOL(netif_receive_skb);
4055 /* Network device is going away, flush any packets still pending
4056 * Called with irqs disabled.
4058 static void flush_backlog(void *arg)
4060 struct net_device *dev = arg;
4061 struct softnet_data *sd = this_cpu_ptr(&softnet_data);
4062 struct sk_buff *skb, *tmp;
4065 skb_queue_walk_safe(&sd->input_pkt_queue, skb, tmp) {
4066 if (skb->dev == dev) {
4067 __skb_unlink(skb, &sd->input_pkt_queue);
4069 input_queue_head_incr(sd);
4074 skb_queue_walk_safe(&sd->process_queue, skb, tmp) {
4075 if (skb->dev == dev) {
4076 __skb_unlink(skb, &sd->process_queue);
4078 input_queue_head_incr(sd);
4083 static int napi_gro_complete(struct sk_buff *skb)
4085 struct packet_offload *ptype;
4086 __be16 type = skb->protocol;
4087 struct list_head *head = &offload_base;
4090 BUILD_BUG_ON(sizeof(struct napi_gro_cb) > sizeof(skb->cb));
4092 if (NAPI_GRO_CB(skb)->count == 1) {
4093 skb_shinfo(skb)->gso_size = 0;
4098 list_for_each_entry_rcu(ptype, head, list) {
4099 if (ptype->type != type || !ptype->callbacks.gro_complete)
4102 err = ptype->callbacks.gro_complete(skb, 0);
4108 WARN_ON(&ptype->list == head);
4110 return NET_RX_SUCCESS;
4114 return netif_receive_skb_internal(skb);
4117 /* napi->gro_list contains packets ordered by age.
4118 * youngest packets at the head of it.
4119 * Complete skbs in reverse order to reduce latencies.
4121 void napi_gro_flush(struct napi_struct *napi, bool flush_old)
4123 struct sk_buff *skb, *prev = NULL;
4125 /* scan list and build reverse chain */
4126 for (skb = napi->gro_list; skb != NULL; skb = skb->next) {
4131 for (skb = prev; skb; skb = prev) {
4134 if (flush_old && NAPI_GRO_CB(skb)->age == jiffies)
4138 napi_gro_complete(skb);
4142 napi->gro_list = NULL;
4144 EXPORT_SYMBOL(napi_gro_flush);
4146 static void gro_list_prepare(struct napi_struct *napi, struct sk_buff *skb)
4149 unsigned int maclen = skb->dev->hard_header_len;
4150 u32 hash = skb_get_hash_raw(skb);
4152 for (p = napi->gro_list; p; p = p->next) {
4153 unsigned long diffs;
4155 NAPI_GRO_CB(p)->flush = 0;
4157 if (hash != skb_get_hash_raw(p)) {
4158 NAPI_GRO_CB(p)->same_flow = 0;
4162 diffs = (unsigned long)p->dev ^ (unsigned long)skb->dev;
4163 diffs |= p->vlan_tci ^ skb->vlan_tci;
4164 diffs |= skb_metadata_dst_cmp(p, skb);
4165 if (maclen == ETH_HLEN)
4166 diffs |= compare_ether_header(skb_mac_header(p),
4167 skb_mac_header(skb));
4169 diffs = memcmp(skb_mac_header(p),
4170 skb_mac_header(skb),
4172 NAPI_GRO_CB(p)->same_flow = !diffs;
4176 static void skb_gro_reset_offset(struct sk_buff *skb)
4178 const struct skb_shared_info *pinfo = skb_shinfo(skb);
4179 const skb_frag_t *frag0 = &pinfo->frags[0];
4181 NAPI_GRO_CB(skb)->data_offset = 0;
4182 NAPI_GRO_CB(skb)->frag0 = NULL;
4183 NAPI_GRO_CB(skb)->frag0_len = 0;
4185 if (skb_mac_header(skb) == skb_tail_pointer(skb) &&
4187 !PageHighMem(skb_frag_page(frag0))) {
4188 NAPI_GRO_CB(skb)->frag0 = skb_frag_address(frag0);
4189 NAPI_GRO_CB(skb)->frag0_len = skb_frag_size(frag0);
4193 static void gro_pull_from_frag0(struct sk_buff *skb, int grow)
4195 struct skb_shared_info *pinfo = skb_shinfo(skb);
4197 BUG_ON(skb->end - skb->tail < grow);
4199 memcpy(skb_tail_pointer(skb), NAPI_GRO_CB(skb)->frag0, grow);
4201 skb->data_len -= grow;
4204 pinfo->frags[0].page_offset += grow;
4205 skb_frag_size_sub(&pinfo->frags[0], grow);
4207 if (unlikely(!skb_frag_size(&pinfo->frags[0]))) {
4208 skb_frag_unref(skb, 0);
4209 memmove(pinfo->frags, pinfo->frags + 1,
4210 --pinfo->nr_frags * sizeof(pinfo->frags[0]));
4214 static enum gro_result dev_gro_receive(struct napi_struct *napi, struct sk_buff *skb)
4216 struct sk_buff **pp = NULL;
4217 struct packet_offload *ptype;
4218 __be16 type = skb->protocol;
4219 struct list_head *head = &offload_base;
4221 enum gro_result ret;
4224 if (!(skb->dev->features & NETIF_F_GRO))
4227 if (skb_is_gso(skb) || skb_has_frag_list(skb) || skb->csum_bad)
4230 gro_list_prepare(napi, skb);
4233 list_for_each_entry_rcu(ptype, head, list) {
4234 if (ptype->type != type || !ptype->callbacks.gro_receive)
4237 skb_set_network_header(skb, skb_gro_offset(skb));
4238 skb_reset_mac_len(skb);
4239 NAPI_GRO_CB(skb)->same_flow = 0;
4240 NAPI_GRO_CB(skb)->flush = 0;
4241 NAPI_GRO_CB(skb)->free = 0;
4242 NAPI_GRO_CB(skb)->encap_mark = 0;
4243 NAPI_GRO_CB(skb)->gro_remcsum_start = 0;
4245 /* Setup for GRO checksum validation */
4246 switch (skb->ip_summed) {
4247 case CHECKSUM_COMPLETE:
4248 NAPI_GRO_CB(skb)->csum = skb->csum;
4249 NAPI_GRO_CB(skb)->csum_valid = 1;
4250 NAPI_GRO_CB(skb)->csum_cnt = 0;
4252 case CHECKSUM_UNNECESSARY:
4253 NAPI_GRO_CB(skb)->csum_cnt = skb->csum_level + 1;
4254 NAPI_GRO_CB(skb)->csum_valid = 0;
4257 NAPI_GRO_CB(skb)->csum_cnt = 0;
4258 NAPI_GRO_CB(skb)->csum_valid = 0;
4261 pp = ptype->callbacks.gro_receive(&napi->gro_list, skb);
4266 if (&ptype->list == head)
4269 same_flow = NAPI_GRO_CB(skb)->same_flow;
4270 ret = NAPI_GRO_CB(skb)->free ? GRO_MERGED_FREE : GRO_MERGED;
4273 struct sk_buff *nskb = *pp;
4277 napi_gro_complete(nskb);
4284 if (NAPI_GRO_CB(skb)->flush)
4287 if (unlikely(napi->gro_count >= MAX_GRO_SKBS)) {
4288 struct sk_buff *nskb = napi->gro_list;
4290 /* locate the end of the list to select the 'oldest' flow */
4291 while (nskb->next) {
4297 napi_gro_complete(nskb);
4301 NAPI_GRO_CB(skb)->count = 1;
4302 NAPI_GRO_CB(skb)->age = jiffies;
4303 NAPI_GRO_CB(skb)->last = skb;
4304 skb_shinfo(skb)->gso_size = skb_gro_len(skb);
4305 skb->next = napi->gro_list;
4306 napi->gro_list = skb;
4310 grow = skb_gro_offset(skb) - skb_headlen(skb);
4312 gro_pull_from_frag0(skb, grow);
4321 struct packet_offload *gro_find_receive_by_type(__be16 type)
4323 struct list_head *offload_head = &offload_base;
4324 struct packet_offload *ptype;
4326 list_for_each_entry_rcu(ptype, offload_head, list) {
4327 if (ptype->type != type || !ptype->callbacks.gro_receive)
4333 EXPORT_SYMBOL(gro_find_receive_by_type);
4335 struct packet_offload *gro_find_complete_by_type(__be16 type)
4337 struct list_head *offload_head = &offload_base;
4338 struct packet_offload *ptype;
4340 list_for_each_entry_rcu(ptype, offload_head, list) {
4341 if (ptype->type != type || !ptype->callbacks.gro_complete)
4347 EXPORT_SYMBOL(gro_find_complete_by_type);
4349 static gro_result_t napi_skb_finish(gro_result_t ret, struct sk_buff *skb)
4353 if (netif_receive_skb_internal(skb))
4361 case GRO_MERGED_FREE:
4362 if (NAPI_GRO_CB(skb)->free == NAPI_GRO_FREE_STOLEN_HEAD) {
4364 kmem_cache_free(skbuff_head_cache, skb);
4378 gro_result_t napi_gro_receive(struct napi_struct *napi, struct sk_buff *skb)
4380 trace_napi_gro_receive_entry(skb);
4382 skb_gro_reset_offset(skb);
4384 return napi_skb_finish(dev_gro_receive(napi, skb), skb);
4386 EXPORT_SYMBOL(napi_gro_receive);
4388 static void napi_reuse_skb(struct napi_struct *napi, struct sk_buff *skb)
4390 if (unlikely(skb->pfmemalloc)) {
4394 __skb_pull(skb, skb_headlen(skb));
4395 /* restore the reserve we had after netdev_alloc_skb_ip_align() */
4396 skb_reserve(skb, NET_SKB_PAD + NET_IP_ALIGN - skb_headroom(skb));
4398 skb->dev = napi->dev;
4400 skb->encapsulation = 0;
4401 skb_shinfo(skb)->gso_type = 0;
4402 skb->truesize = SKB_TRUESIZE(skb_end_offset(skb));
4407 struct sk_buff *napi_get_frags(struct napi_struct *napi)
4409 struct sk_buff *skb = napi->skb;
4412 skb = napi_alloc_skb(napi, GRO_MAX_HEAD);
4417 EXPORT_SYMBOL(napi_get_frags);
4419 static gro_result_t napi_frags_finish(struct napi_struct *napi,
4420 struct sk_buff *skb,
4426 __skb_push(skb, ETH_HLEN);
4427 skb->protocol = eth_type_trans(skb, skb->dev);
4428 if (ret == GRO_NORMAL && netif_receive_skb_internal(skb))
4433 case GRO_MERGED_FREE:
4434 napi_reuse_skb(napi, skb);
4444 /* Upper GRO stack assumes network header starts at gro_offset=0
4445 * Drivers could call both napi_gro_frags() and napi_gro_receive()
4446 * We copy ethernet header into skb->data to have a common layout.
4448 static struct sk_buff *napi_frags_skb(struct napi_struct *napi)
4450 struct sk_buff *skb = napi->skb;
4451 const struct ethhdr *eth;
4452 unsigned int hlen = sizeof(*eth);
4456 skb_reset_mac_header(skb);
4457 skb_gro_reset_offset(skb);
4459 eth = skb_gro_header_fast(skb, 0);
4460 if (unlikely(skb_gro_header_hard(skb, hlen))) {
4461 eth = skb_gro_header_slow(skb, hlen, 0);
4462 if (unlikely(!eth)) {
4463 napi_reuse_skb(napi, skb);
4467 gro_pull_from_frag0(skb, hlen);
4468 NAPI_GRO_CB(skb)->frag0 += hlen;
4469 NAPI_GRO_CB(skb)->frag0_len -= hlen;
4471 __skb_pull(skb, hlen);
4474 * This works because the only protocols we care about don't require
4476 * We'll fix it up properly in napi_frags_finish()
4478 skb->protocol = eth->h_proto;
4483 gro_result_t napi_gro_frags(struct napi_struct *napi)
4485 struct sk_buff *skb = napi_frags_skb(napi);
4490 trace_napi_gro_frags_entry(skb);
4492 return napi_frags_finish(napi, skb, dev_gro_receive(napi, skb));
4494 EXPORT_SYMBOL(napi_gro_frags);
4496 /* Compute the checksum from gro_offset and return the folded value
4497 * after adding in any pseudo checksum.
4499 __sum16 __skb_gro_checksum_complete(struct sk_buff *skb)
4504 wsum = skb_checksum(skb, skb_gro_offset(skb), skb_gro_len(skb), 0);
4506 /* NAPI_GRO_CB(skb)->csum holds pseudo checksum */
4507 sum = csum_fold(csum_add(NAPI_GRO_CB(skb)->csum, wsum));
4509 if (unlikely(skb->ip_summed == CHECKSUM_COMPLETE) &&
4510 !skb->csum_complete_sw)
4511 netdev_rx_csum_fault(skb->dev);
4514 NAPI_GRO_CB(skb)->csum = wsum;
4515 NAPI_GRO_CB(skb)->csum_valid = 1;
4519 EXPORT_SYMBOL(__skb_gro_checksum_complete);
4522 * net_rps_action_and_irq_enable sends any pending IPI's for rps.
4523 * Note: called with local irq disabled, but exits with local irq enabled.
4525 static void net_rps_action_and_irq_enable(struct softnet_data *sd)
4528 struct softnet_data *remsd = sd->rps_ipi_list;
4531 sd->rps_ipi_list = NULL;
4535 /* Send pending IPI's to kick RPS processing on remote cpus. */
4537 struct softnet_data *next = remsd->rps_ipi_next;
4539 if (cpu_online(remsd->cpu))
4540 smp_call_function_single_async(remsd->cpu,
4549 static bool sd_has_rps_ipi_waiting(struct softnet_data *sd)
4552 return sd->rps_ipi_list != NULL;
4558 static int process_backlog(struct napi_struct *napi, int quota)
4561 struct softnet_data *sd = container_of(napi, struct softnet_data, backlog);
4563 /* Check if we have pending ipi, its better to send them now,
4564 * not waiting net_rx_action() end.
4566 if (sd_has_rps_ipi_waiting(sd)) {
4567 local_irq_disable();
4568 net_rps_action_and_irq_enable(sd);
4571 napi->weight = weight_p;
4572 local_irq_disable();
4574 struct sk_buff *skb;
4576 while ((skb = __skb_dequeue(&sd->process_queue))) {
4579 __netif_receive_skb(skb);
4581 local_irq_disable();
4582 input_queue_head_incr(sd);
4583 if (++work >= quota) {
4590 if (skb_queue_empty(&sd->input_pkt_queue)) {
4592 * Inline a custom version of __napi_complete().
4593 * only current cpu owns and manipulates this napi,
4594 * and NAPI_STATE_SCHED is the only possible flag set
4596 * We can use a plain write instead of clear_bit(),
4597 * and we dont need an smp_mb() memory barrier.
4605 skb_queue_splice_tail_init(&sd->input_pkt_queue,
4606 &sd->process_queue);
4615 * __napi_schedule - schedule for receive
4616 * @n: entry to schedule
4618 * The entry's receive function will be scheduled to run.
4619 * Consider using __napi_schedule_irqoff() if hard irqs are masked.
4621 void __napi_schedule(struct napi_struct *n)
4623 unsigned long flags;
4625 local_irq_save(flags);
4626 ____napi_schedule(this_cpu_ptr(&softnet_data), n);
4627 local_irq_restore(flags);
4629 EXPORT_SYMBOL(__napi_schedule);
4632 * __napi_schedule_irqoff - schedule for receive
4633 * @n: entry to schedule
4635 * Variant of __napi_schedule() assuming hard irqs are masked
4637 void __napi_schedule_irqoff(struct napi_struct *n)
4639 ____napi_schedule(this_cpu_ptr(&softnet_data), n);
4641 EXPORT_SYMBOL(__napi_schedule_irqoff);
4643 void __napi_complete(struct napi_struct *n)
4645 BUG_ON(!test_bit(NAPI_STATE_SCHED, &n->state));
4647 list_del_init(&n->poll_list);
4648 smp_mb__before_atomic();
4649 clear_bit(NAPI_STATE_SCHED, &n->state);
4651 EXPORT_SYMBOL(__napi_complete);
4653 void napi_complete_done(struct napi_struct *n, int work_done)
4655 unsigned long flags;
4658 * don't let napi dequeue from the cpu poll list
4659 * just in case its running on a different cpu
4661 if (unlikely(test_bit(NAPI_STATE_NPSVC, &n->state)))
4665 unsigned long timeout = 0;
4668 timeout = n->dev->gro_flush_timeout;
4671 hrtimer_start(&n->timer, ns_to_ktime(timeout),
4672 HRTIMER_MODE_REL_PINNED);
4674 napi_gro_flush(n, false);
4676 if (likely(list_empty(&n->poll_list))) {
4677 WARN_ON_ONCE(!test_and_clear_bit(NAPI_STATE_SCHED, &n->state));
4679 /* If n->poll_list is not empty, we need to mask irqs */
4680 local_irq_save(flags);
4682 local_irq_restore(flags);
4685 EXPORT_SYMBOL(napi_complete_done);
4687 /* must be called under rcu_read_lock(), as we dont take a reference */
4688 struct napi_struct *napi_by_id(unsigned int napi_id)
4690 unsigned int hash = napi_id % HASH_SIZE(napi_hash);
4691 struct napi_struct *napi;
4693 hlist_for_each_entry_rcu(napi, &napi_hash[hash], napi_hash_node)
4694 if (napi->napi_id == napi_id)
4699 EXPORT_SYMBOL_GPL(napi_by_id);
4701 void napi_hash_add(struct napi_struct *napi)
4703 if (!test_and_set_bit(NAPI_STATE_HASHED, &napi->state)) {
4705 spin_lock(&napi_hash_lock);
4707 /* 0 is not a valid id, we also skip an id that is taken
4708 * we expect both events to be extremely rare
4711 while (!napi->napi_id) {
4712 napi->napi_id = ++napi_gen_id;
4713 if (napi_by_id(napi->napi_id))
4717 hlist_add_head_rcu(&napi->napi_hash_node,
4718 &napi_hash[napi->napi_id % HASH_SIZE(napi_hash)]);
4720 spin_unlock(&napi_hash_lock);
4723 EXPORT_SYMBOL_GPL(napi_hash_add);
4725 /* Warning : caller is responsible to make sure rcu grace period
4726 * is respected before freeing memory containing @napi
4728 void napi_hash_del(struct napi_struct *napi)
4730 spin_lock(&napi_hash_lock);
4732 if (test_and_clear_bit(NAPI_STATE_HASHED, &napi->state))
4733 hlist_del_rcu(&napi->napi_hash_node);
4735 spin_unlock(&napi_hash_lock);
4737 EXPORT_SYMBOL_GPL(napi_hash_del);
4739 static enum hrtimer_restart napi_watchdog(struct hrtimer *timer)
4741 struct napi_struct *napi;
4743 napi = container_of(timer, struct napi_struct, timer);
4745 napi_schedule(napi);
4747 return HRTIMER_NORESTART;
4750 void netif_napi_add(struct net_device *dev, struct napi_struct *napi,
4751 int (*poll)(struct napi_struct *, int), int weight)
4753 INIT_LIST_HEAD(&napi->poll_list);
4754 hrtimer_init(&napi->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_PINNED);
4755 napi->timer.function = napi_watchdog;
4756 napi->gro_count = 0;
4757 napi->gro_list = NULL;
4760 if (weight > NAPI_POLL_WEIGHT)
4761 pr_err_once("netif_napi_add() called with weight %d on device %s\n",
4763 napi->weight = weight;
4764 list_add(&napi->dev_list, &dev->napi_list);
4766 #ifdef CONFIG_NETPOLL
4767 spin_lock_init(&napi->poll_lock);
4768 napi->poll_owner = -1;
4770 set_bit(NAPI_STATE_SCHED, &napi->state);
4772 EXPORT_SYMBOL(netif_napi_add);
4774 void napi_disable(struct napi_struct *n)
4777 set_bit(NAPI_STATE_DISABLE, &n->state);
4779 while (test_and_set_bit(NAPI_STATE_SCHED, &n->state))
4781 while (test_and_set_bit(NAPI_STATE_NPSVC, &n->state))
4784 hrtimer_cancel(&n->timer);
4786 clear_bit(NAPI_STATE_DISABLE, &n->state);
4788 EXPORT_SYMBOL(napi_disable);
4790 void netif_napi_del(struct napi_struct *napi)
4792 list_del_init(&napi->dev_list);
4793 napi_free_frags(napi);
4795 kfree_skb_list(napi->gro_list);
4796 napi->gro_list = NULL;
4797 napi->gro_count = 0;
4799 EXPORT_SYMBOL(netif_napi_del);
4801 static int napi_poll(struct napi_struct *n, struct list_head *repoll)
4806 list_del_init(&n->poll_list);
4808 have = netpoll_poll_lock(n);
4812 /* This NAPI_STATE_SCHED test is for avoiding a race
4813 * with netpoll's poll_napi(). Only the entity which
4814 * obtains the lock and sees NAPI_STATE_SCHED set will
4815 * actually make the ->poll() call. Therefore we avoid
4816 * accidentally calling ->poll() when NAPI is not scheduled.
4819 if (test_bit(NAPI_STATE_SCHED, &n->state)) {
4820 work = n->poll(n, weight);
4824 WARN_ON_ONCE(work > weight);
4826 if (likely(work < weight))
4829 /* Drivers must not modify the NAPI state if they
4830 * consume the entire weight. In such cases this code
4831 * still "owns" the NAPI instance and therefore can
4832 * move the instance around on the list at-will.
4834 if (unlikely(napi_disable_pending(n))) {
4840 /* flush too old packets
4841 * If HZ < 1000, flush all packets.
4843 napi_gro_flush(n, HZ >= 1000);
4846 /* Some drivers may have called napi_schedule
4847 * prior to exhausting their budget.
4849 if (unlikely(!list_empty(&n->poll_list))) {
4850 pr_warn_once("%s: Budget exhausted after napi rescheduled\n",
4851 n->dev ? n->dev->name : "backlog");
4855 list_add_tail(&n->poll_list, repoll);
4858 netpoll_poll_unlock(have);
4863 static void net_rx_action(struct softirq_action *h)
4865 struct softnet_data *sd = this_cpu_ptr(&softnet_data);
4866 unsigned long time_limit = jiffies + 2;
4867 int budget = netdev_budget;
4871 local_irq_disable();
4872 list_splice_init(&sd->poll_list, &list);
4876 struct napi_struct *n;
4878 if (list_empty(&list)) {
4879 if (!sd_has_rps_ipi_waiting(sd) && list_empty(&repoll))
4884 n = list_first_entry(&list, struct napi_struct, poll_list);
4885 budget -= napi_poll(n, &repoll);
4887 /* If softirq window is exhausted then punt.
4888 * Allow this to run for 2 jiffies since which will allow
4889 * an average latency of 1.5/HZ.
4891 if (unlikely(budget <= 0 ||
4892 time_after_eq(jiffies, time_limit))) {
4898 local_irq_disable();
4900 list_splice_tail_init(&sd->poll_list, &list);
4901 list_splice_tail(&repoll, &list);
4902 list_splice(&list, &sd->poll_list);
4903 if (!list_empty(&sd->poll_list))
4904 __raise_softirq_irqoff(NET_RX_SOFTIRQ);
4906 net_rps_action_and_irq_enable(sd);
4909 struct netdev_adjacent {
4910 struct net_device *dev;
4912 /* upper master flag, there can only be one master device per list */
4915 /* counter for the number of times this device was added to us */
4918 /* private field for the users */
4921 struct list_head list;
4922 struct rcu_head rcu;
4925 static struct netdev_adjacent *__netdev_find_adj(struct net_device *adj_dev,
4926 struct list_head *adj_list)
4928 struct netdev_adjacent *adj;
4930 list_for_each_entry(adj, adj_list, list) {
4931 if (adj->dev == adj_dev)
4938 * netdev_has_upper_dev - Check if device is linked to an upper device
4940 * @upper_dev: upper device to check
4942 * Find out if a device is linked to specified upper device and return true
4943 * in case it is. Note that this checks only immediate upper device,
4944 * not through a complete stack of devices. The caller must hold the RTNL lock.
4946 bool netdev_has_upper_dev(struct net_device *dev,
4947 struct net_device *upper_dev)
4951 return __netdev_find_adj(upper_dev, &dev->all_adj_list.upper);
4953 EXPORT_SYMBOL(netdev_has_upper_dev);
4956 * netdev_has_any_upper_dev - Check if device is linked to some device
4959 * Find out if a device is linked to an upper device and return true in case
4960 * it is. The caller must hold the RTNL lock.
4962 static bool netdev_has_any_upper_dev(struct net_device *dev)
4966 return !list_empty(&dev->all_adj_list.upper);
4970 * netdev_master_upper_dev_get - Get master upper device
4973 * Find a master upper device and return pointer to it or NULL in case
4974 * it's not there. The caller must hold the RTNL lock.
4976 struct net_device *netdev_master_upper_dev_get(struct net_device *dev)
4978 struct netdev_adjacent *upper;
4982 if (list_empty(&dev->adj_list.upper))
4985 upper = list_first_entry(&dev->adj_list.upper,
4986 struct netdev_adjacent, list);
4987 if (likely(upper->master))
4991 EXPORT_SYMBOL(netdev_master_upper_dev_get);
4993 void *netdev_adjacent_get_private(struct list_head *adj_list)
4995 struct netdev_adjacent *adj;
4997 adj = list_entry(adj_list, struct netdev_adjacent, list);
4999 return adj->private;
5001 EXPORT_SYMBOL(netdev_adjacent_get_private);
5004 * netdev_upper_get_next_dev_rcu - Get the next dev from upper list
5006 * @iter: list_head ** of the current position
5008 * Gets the next device from the dev's upper list, starting from iter
5009 * position. The caller must hold RCU read lock.
5011 struct net_device *netdev_upper_get_next_dev_rcu(struct net_device *dev,
5012 struct list_head **iter)
5014 struct netdev_adjacent *upper;
5016 WARN_ON_ONCE(!rcu_read_lock_held() && !lockdep_rtnl_is_held());
5018 upper = list_entry_rcu((*iter)->next, struct netdev_adjacent, list);
5020 if (&upper->list == &dev->adj_list.upper)
5023 *iter = &upper->list;
5027 EXPORT_SYMBOL(netdev_upper_get_next_dev_rcu);
5030 * netdev_all_upper_get_next_dev_rcu - Get the next dev from upper list
5032 * @iter: list_head ** of the current position
5034 * Gets the next device from the dev's upper list, starting from iter
5035 * position. The caller must hold RCU read lock.
5037 struct net_device *netdev_all_upper_get_next_dev_rcu(struct net_device *dev,
5038 struct list_head **iter)
5040 struct netdev_adjacent *upper;
5042 WARN_ON_ONCE(!rcu_read_lock_held() && !lockdep_rtnl_is_held());
5044 upper = list_entry_rcu((*iter)->next, struct netdev_adjacent, list);
5046 if (&upper->list == &dev->all_adj_list.upper)
5049 *iter = &upper->list;
5053 EXPORT_SYMBOL(netdev_all_upper_get_next_dev_rcu);
5056 * netdev_lower_get_next_private - Get the next ->private from the
5057 * lower neighbour list
5059 * @iter: list_head ** of the current position
5061 * Gets the next netdev_adjacent->private from the dev's lower neighbour
5062 * list, starting from iter position. The caller must hold either hold the
5063 * RTNL lock or its own locking that guarantees that the neighbour lower
5064 * list will remain unchanged.
5066 void *netdev_lower_get_next_private(struct net_device *dev,
5067 struct list_head **iter)
5069 struct netdev_adjacent *lower;
5071 lower = list_entry(*iter, struct netdev_adjacent, list);
5073 if (&lower->list == &dev->adj_list.lower)
5076 *iter = lower->list.next;
5078 return lower->private;
5080 EXPORT_SYMBOL(netdev_lower_get_next_private);
5083 * netdev_lower_get_next_private_rcu - Get the next ->private from the
5084 * lower neighbour list, RCU
5087 * @iter: list_head ** of the current position
5089 * Gets the next netdev_adjacent->private from the dev's lower neighbour
5090 * list, starting from iter position. The caller must hold RCU read lock.
5092 void *netdev_lower_get_next_private_rcu(struct net_device *dev,
5093 struct list_head **iter)
5095 struct netdev_adjacent *lower;
5097 WARN_ON_ONCE(!rcu_read_lock_held());
5099 lower = list_entry_rcu((*iter)->next, struct netdev_adjacent, list);
5101 if (&lower->list == &dev->adj_list.lower)
5104 *iter = &lower->list;
5106 return lower->private;
5108 EXPORT_SYMBOL(netdev_lower_get_next_private_rcu);
5111 * netdev_lower_get_next - Get the next device from the lower neighbour
5114 * @iter: list_head ** of the current position
5116 * Gets the next netdev_adjacent from the dev's lower neighbour
5117 * list, starting from iter position. The caller must hold RTNL lock or
5118 * its own locking that guarantees that the neighbour lower
5119 * list will remain unchanged.
5121 void *netdev_lower_get_next(struct net_device *dev, struct list_head **iter)
5123 struct netdev_adjacent *lower;
5125 lower = list_entry((*iter)->next, struct netdev_adjacent, list);
5127 if (&lower->list == &dev->adj_list.lower)
5130 *iter = &lower->list;
5134 EXPORT_SYMBOL(netdev_lower_get_next);
5137 * netdev_lower_get_first_private_rcu - Get the first ->private from the
5138 * lower neighbour list, RCU
5142 * Gets the first netdev_adjacent->private from the dev's lower neighbour
5143 * list. The caller must hold RCU read lock.
5145 void *netdev_lower_get_first_private_rcu(struct net_device *dev)
5147 struct netdev_adjacent *lower;
5149 lower = list_first_or_null_rcu(&dev->adj_list.lower,
5150 struct netdev_adjacent, list);
5152 return lower->private;
5155 EXPORT_SYMBOL(netdev_lower_get_first_private_rcu);
5158 * netdev_master_upper_dev_get_rcu - Get master upper device
5161 * Find a master upper device and return pointer to it or NULL in case
5162 * it's not there. The caller must hold the RCU read lock.
5164 struct net_device *netdev_master_upper_dev_get_rcu(struct net_device *dev)
5166 struct netdev_adjacent *upper;
5168 upper = list_first_or_null_rcu(&dev->adj_list.upper,
5169 struct netdev_adjacent, list);
5170 if (upper && likely(upper->master))
5174 EXPORT_SYMBOL(netdev_master_upper_dev_get_rcu);
5176 static int netdev_adjacent_sysfs_add(struct net_device *dev,
5177 struct net_device *adj_dev,
5178 struct list_head *dev_list)
5180 char linkname[IFNAMSIZ+7];
5181 sprintf(linkname, dev_list == &dev->adj_list.upper ?
5182 "upper_%s" : "lower_%s", adj_dev->name);
5183 return sysfs_create_link(&(dev->dev.kobj), &(adj_dev->dev.kobj),
5186 static void netdev_adjacent_sysfs_del(struct net_device *dev,
5188 struct list_head *dev_list)
5190 char linkname[IFNAMSIZ+7];
5191 sprintf(linkname, dev_list == &dev->adj_list.upper ?
5192 "upper_%s" : "lower_%s", name);
5193 sysfs_remove_link(&(dev->dev.kobj), linkname);
5196 static inline bool netdev_adjacent_is_neigh_list(struct net_device *dev,
5197 struct net_device *adj_dev,
5198 struct list_head *dev_list)
5200 return (dev_list == &dev->adj_list.upper ||
5201 dev_list == &dev->adj_list.lower) &&
5202 net_eq(dev_net(dev), dev_net(adj_dev));
5205 static int __netdev_adjacent_dev_insert(struct net_device *dev,
5206 struct net_device *adj_dev,
5208 struct list_head *dev_list,
5209 void *private, bool master)
5211 struct netdev_adjacent *adj;
5214 adj = __netdev_find_adj(adj_dev, dev_list);
5217 adj->ref_nr += ref_nr;
5221 adj = kmalloc(sizeof(*adj), GFP_KERNEL);
5226 adj->master = master;
5227 adj->ref_nr = ref_nr;
5228 adj->private = private;
5231 pr_debug("dev_hold for %s, because of link added from %s to %s\n",
5232 adj_dev->name, dev->name, adj_dev->name);
5234 if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list)) {
5235 ret = netdev_adjacent_sysfs_add(dev, adj_dev, dev_list);
5240 /* Ensure that master link is always the first item in list. */
5242 ret = sysfs_create_link(&(dev->dev.kobj),
5243 &(adj_dev->dev.kobj), "master");
5245 goto remove_symlinks;
5247 list_add_rcu(&adj->list, dev_list);
5249 list_add_tail_rcu(&adj->list, dev_list);
5255 if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list))
5256 netdev_adjacent_sysfs_del(dev, adj_dev->name, dev_list);
5264 static void __netdev_adjacent_dev_remove(struct net_device *dev,
5265 struct net_device *adj_dev,
5267 struct list_head *dev_list)
5269 struct netdev_adjacent *adj;
5271 adj = __netdev_find_adj(adj_dev, dev_list);
5274 pr_err("tried to remove device %s from %s\n",
5275 dev->name, adj_dev->name);
5279 if (adj->ref_nr > ref_nr) {
5280 pr_debug("%s to %s ref_nr-%d = %d\n", dev->name, adj_dev->name,
5281 ref_nr, adj->ref_nr-ref_nr);
5282 adj->ref_nr -= ref_nr;
5287 sysfs_remove_link(&(dev->dev.kobj), "master");
5289 if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list))
5290 netdev_adjacent_sysfs_del(dev, adj_dev->name, dev_list);
5292 list_del_rcu(&adj->list);
5293 pr_debug("dev_put for %s, because link removed from %s to %s\n",
5294 adj_dev->name, dev->name, adj_dev->name);
5296 kfree_rcu(adj, rcu);
5299 static int __netdev_adjacent_dev_link_lists(struct net_device *dev,
5300 struct net_device *upper_dev,
5302 struct list_head *up_list,
5303 struct list_head *down_list,
5304 void *private, bool master)
5308 ret = __netdev_adjacent_dev_insert(dev, upper_dev, ref_nr, up_list,
5313 ret = __netdev_adjacent_dev_insert(upper_dev, dev, ref_nr, down_list,
5316 __netdev_adjacent_dev_remove(dev, upper_dev, ref_nr, up_list);
5323 static int __netdev_adjacent_dev_link(struct net_device *dev,
5324 struct net_device *upper_dev,
5327 return __netdev_adjacent_dev_link_lists(dev, upper_dev, ref_nr,
5328 &dev->all_adj_list.upper,
5329 &upper_dev->all_adj_list.lower,
5333 static void __netdev_adjacent_dev_unlink_lists(struct net_device *dev,
5334 struct net_device *upper_dev,
5336 struct list_head *up_list,
5337 struct list_head *down_list)
5339 __netdev_adjacent_dev_remove(dev, upper_dev, ref_nr, up_list);
5340 __netdev_adjacent_dev_remove(upper_dev, dev, ref_nr, down_list);
5343 static void __netdev_adjacent_dev_unlink(struct net_device *dev,
5344 struct net_device *upper_dev,
5347 __netdev_adjacent_dev_unlink_lists(dev, upper_dev, ref_nr,
5348 &dev->all_adj_list.upper,
5349 &upper_dev->all_adj_list.lower);
5352 static int __netdev_adjacent_dev_link_neighbour(struct net_device *dev,
5353 struct net_device *upper_dev,
5354 void *private, bool master)
5356 int ret = __netdev_adjacent_dev_link(dev, upper_dev, 1);
5361 ret = __netdev_adjacent_dev_link_lists(dev, upper_dev, 1,
5362 &dev->adj_list.upper,
5363 &upper_dev->adj_list.lower,
5366 __netdev_adjacent_dev_unlink(dev, upper_dev, 1);
5373 static void __netdev_adjacent_dev_unlink_neighbour(struct net_device *dev,
5374 struct net_device *upper_dev)
5376 __netdev_adjacent_dev_unlink(dev, upper_dev, 1);
5377 __netdev_adjacent_dev_unlink_lists(dev, upper_dev, 1,
5378 &dev->adj_list.upper,
5379 &upper_dev->adj_list.lower);
5382 static int __netdev_upper_dev_link(struct net_device *dev,
5383 struct net_device *upper_dev, bool master,
5386 struct netdev_notifier_changeupper_info changeupper_info;
5387 struct netdev_adjacent *i, *j, *to_i, *to_j;
5392 if (dev == upper_dev)
5395 /* To prevent loops, check if dev is not upper device to upper_dev. */
5396 if (__netdev_find_adj(dev, &upper_dev->all_adj_list.upper))
5399 if (__netdev_find_adj(upper_dev, &dev->adj_list.upper))
5402 if (master && netdev_master_upper_dev_get(dev))
5405 changeupper_info.upper_dev = upper_dev;
5406 changeupper_info.master = master;
5407 changeupper_info.linking = true;
5409 ret = call_netdevice_notifiers_info(NETDEV_PRECHANGEUPPER, dev,
5410 &changeupper_info.info);
5411 ret = notifier_to_errno(ret);
5415 ret = __netdev_adjacent_dev_link_neighbour(dev, upper_dev, private,
5420 /* Now that we linked these devs, make all the upper_dev's
5421 * all_adj_list.upper visible to every dev's all_adj_list.lower an
5422 * versa, and don't forget the devices itself. All of these
5423 * links are non-neighbours.
5425 list_for_each_entry(i, &dev->all_adj_list.lower, list) {
5426 list_for_each_entry(j, &upper_dev->all_adj_list.upper, list) {
5427 pr_debug("Interlinking %s with %s, non-neighbour\n",
5428 i->dev->name, j->dev->name);
5429 ret = __netdev_adjacent_dev_link(i->dev, j->dev, i->ref_nr);
5435 /* add dev to every upper_dev's upper device */
5436 list_for_each_entry(i, &upper_dev->all_adj_list.upper, list) {
5437 pr_debug("linking %s's upper device %s with %s\n",
5438 upper_dev->name, i->dev->name, dev->name);
5439 ret = __netdev_adjacent_dev_link(dev, i->dev, i->ref_nr);
5441 goto rollback_upper_mesh;
5444 /* add upper_dev to every dev's lower device */
5445 list_for_each_entry(i, &dev->all_adj_list.lower, list) {
5446 pr_debug("linking %s's lower device %s with %s\n", dev->name,
5447 i->dev->name, upper_dev->name);
5448 ret = __netdev_adjacent_dev_link(i->dev, upper_dev, i->ref_nr);
5450 goto rollback_lower_mesh;
5453 call_netdevice_notifiers_info(NETDEV_CHANGEUPPER, dev,
5454 &changeupper_info.info);
5457 rollback_lower_mesh:
5459 list_for_each_entry(i, &dev->all_adj_list.lower, list) {
5462 __netdev_adjacent_dev_unlink(i->dev, upper_dev, i->ref_nr);
5467 rollback_upper_mesh:
5469 list_for_each_entry(i, &upper_dev->all_adj_list.upper, list) {
5472 __netdev_adjacent_dev_unlink(dev, i->dev, i->ref_nr);
5480 list_for_each_entry(i, &dev->all_adj_list.lower, list) {
5481 list_for_each_entry(j, &upper_dev->all_adj_list.upper, list) {
5482 if (i == to_i && j == to_j)
5484 __netdev_adjacent_dev_unlink(i->dev, j->dev, i->ref_nr);
5490 __netdev_adjacent_dev_unlink_neighbour(dev, upper_dev);
5496 * netdev_upper_dev_link - Add a link to the upper device
5498 * @upper_dev: new upper device
5500 * Adds a link to device which is upper to this one. The caller must hold
5501 * the RTNL lock. On a failure a negative errno code is returned.
5502 * On success the reference counts are adjusted and the function
5505 int netdev_upper_dev_link(struct net_device *dev,
5506 struct net_device *upper_dev)
5508 return __netdev_upper_dev_link(dev, upper_dev, false, NULL);
5510 EXPORT_SYMBOL(netdev_upper_dev_link);
5513 * netdev_master_upper_dev_link - Add a master link to the upper device
5515 * @upper_dev: new upper device
5517 * Adds a link to device which is upper to this one. In this case, only
5518 * one master upper device can be linked, although other non-master devices
5519 * might be linked as well. The caller must hold the RTNL lock.
5520 * On a failure a negative errno code is returned. On success the reference
5521 * counts are adjusted and the function returns zero.
5523 int netdev_master_upper_dev_link(struct net_device *dev,
5524 struct net_device *upper_dev)
5526 return __netdev_upper_dev_link(dev, upper_dev, true, NULL);
5528 EXPORT_SYMBOL(netdev_master_upper_dev_link);
5530 int netdev_master_upper_dev_link_private(struct net_device *dev,
5531 struct net_device *upper_dev,
5534 return __netdev_upper_dev_link(dev, upper_dev, true, private);
5536 EXPORT_SYMBOL(netdev_master_upper_dev_link_private);
5539 * netdev_upper_dev_unlink - Removes a link to upper device
5541 * @upper_dev: new upper device
5543 * Removes a link to device which is upper to this one. The caller must hold
5546 void netdev_upper_dev_unlink(struct net_device *dev,
5547 struct net_device *upper_dev)
5549 struct netdev_notifier_changeupper_info changeupper_info;
5550 struct netdev_adjacent *i, *j;
5553 changeupper_info.upper_dev = upper_dev;
5554 changeupper_info.master = netdev_master_upper_dev_get(dev) == upper_dev;
5555 changeupper_info.linking = false;
5557 call_netdevice_notifiers_info(NETDEV_PRECHANGEUPPER, dev,
5558 &changeupper_info.info);
5560 __netdev_adjacent_dev_unlink_neighbour(dev, upper_dev);
5562 /* Here is the tricky part. We must remove all dev's lower
5563 * devices from all upper_dev's upper devices and vice
5564 * versa, to maintain the graph relationship.
5566 list_for_each_entry(i, &dev->all_adj_list.lower, list)
5567 list_for_each_entry(j, &upper_dev->all_adj_list.upper, list)
5568 __netdev_adjacent_dev_unlink(i->dev, j->dev, i->ref_nr);
5570 /* remove also the devices itself from lower/upper device
5573 list_for_each_entry(i, &dev->all_adj_list.lower, list)
5574 __netdev_adjacent_dev_unlink(i->dev, upper_dev, i->ref_nr);
5576 list_for_each_entry(i, &upper_dev->all_adj_list.upper, list)
5577 __netdev_adjacent_dev_unlink(dev, i->dev, i->ref_nr);
5579 call_netdevice_notifiers_info(NETDEV_CHANGEUPPER, dev,
5580 &changeupper_info.info);
5582 EXPORT_SYMBOL(netdev_upper_dev_unlink);
5585 * netdev_bonding_info_change - Dispatch event about slave change
5587 * @bonding_info: info to dispatch
5589 * Send NETDEV_BONDING_INFO to netdev notifiers with info.
5590 * The caller must hold the RTNL lock.
5592 void netdev_bonding_info_change(struct net_device *dev,
5593 struct netdev_bonding_info *bonding_info)
5595 struct netdev_notifier_bonding_info info;
5597 memcpy(&info.bonding_info, bonding_info,
5598 sizeof(struct netdev_bonding_info));
5599 call_netdevice_notifiers_info(NETDEV_BONDING_INFO, dev,
5602 EXPORT_SYMBOL(netdev_bonding_info_change);
5604 static void netdev_adjacent_add_links(struct net_device *dev)
5606 struct netdev_adjacent *iter;
5608 struct net *net = dev_net(dev);
5610 list_for_each_entry(iter, &dev->adj_list.upper, list) {
5611 if (!net_eq(net,dev_net(iter->dev)))
5613 netdev_adjacent_sysfs_add(iter->dev, dev,
5614 &iter->dev->adj_list.lower);
5615 netdev_adjacent_sysfs_add(dev, iter->dev,
5616 &dev->adj_list.upper);
5619 list_for_each_entry(iter, &dev->adj_list.lower, list) {
5620 if (!net_eq(net,dev_net(iter->dev)))
5622 netdev_adjacent_sysfs_add(iter->dev, dev,
5623 &iter->dev->adj_list.upper);
5624 netdev_adjacent_sysfs_add(dev, iter->dev,
5625 &dev->adj_list.lower);
5629 static void netdev_adjacent_del_links(struct net_device *dev)
5631 struct netdev_adjacent *iter;
5633 struct net *net = dev_net(dev);
5635 list_for_each_entry(iter, &dev->adj_list.upper, list) {
5636 if (!net_eq(net,dev_net(iter->dev)))
5638 netdev_adjacent_sysfs_del(iter->dev, dev->name,
5639 &iter->dev->adj_list.lower);
5640 netdev_adjacent_sysfs_del(dev, iter->dev->name,
5641 &dev->adj_list.upper);
5644 list_for_each_entry(iter, &dev->adj_list.lower, list) {
5645 if (!net_eq(net,dev_net(iter->dev)))
5647 netdev_adjacent_sysfs_del(iter->dev, dev->name,
5648 &iter->dev->adj_list.upper);
5649 netdev_adjacent_sysfs_del(dev, iter->dev->name,
5650 &dev->adj_list.lower);
5654 void netdev_adjacent_rename_links(struct net_device *dev, char *oldname)
5656 struct netdev_adjacent *iter;
5658 struct net *net = dev_net(dev);
5660 list_for_each_entry(iter, &dev->adj_list.upper, list) {
5661 if (!net_eq(net,dev_net(iter->dev)))
5663 netdev_adjacent_sysfs_del(iter->dev, oldname,
5664 &iter->dev->adj_list.lower);
5665 netdev_adjacent_sysfs_add(iter->dev, dev,
5666 &iter->dev->adj_list.lower);
5669 list_for_each_entry(iter, &dev->adj_list.lower, list) {
5670 if (!net_eq(net,dev_net(iter->dev)))
5672 netdev_adjacent_sysfs_del(iter->dev, oldname,
5673 &iter->dev->adj_list.upper);
5674 netdev_adjacent_sysfs_add(iter->dev, dev,
5675 &iter->dev->adj_list.upper);
5679 void *netdev_lower_dev_get_private(struct net_device *dev,
5680 struct net_device *lower_dev)
5682 struct netdev_adjacent *lower;
5686 lower = __netdev_find_adj(lower_dev, &dev->adj_list.lower);
5690 return lower->private;
5692 EXPORT_SYMBOL(netdev_lower_dev_get_private);
5695 int dev_get_nest_level(struct net_device *dev,
5696 bool (*type_check)(struct net_device *dev))
5698 struct net_device *lower = NULL;
5699 struct list_head *iter;
5705 netdev_for_each_lower_dev(dev, lower, iter) {
5706 nest = dev_get_nest_level(lower, type_check);
5707 if (max_nest < nest)
5711 if (type_check(dev))
5716 EXPORT_SYMBOL(dev_get_nest_level);
5718 static void dev_change_rx_flags(struct net_device *dev, int flags)
5720 const struct net_device_ops *ops = dev->netdev_ops;
5722 if (ops->ndo_change_rx_flags)
5723 ops->ndo_change_rx_flags(dev, flags);
5726 static int __dev_set_promiscuity(struct net_device *dev, int inc, bool notify)
5728 unsigned int old_flags = dev->flags;
5734 dev->flags |= IFF_PROMISC;
5735 dev->promiscuity += inc;
5736 if (dev->promiscuity == 0) {
5739 * If inc causes overflow, untouch promisc and return error.
5742 dev->flags &= ~IFF_PROMISC;
5744 dev->promiscuity -= inc;
5745 pr_warn("%s: promiscuity touches roof, set promiscuity failed. promiscuity feature of device might be broken.\n",
5750 if (dev->flags != old_flags) {
5751 pr_info("device %s %s promiscuous mode\n",
5753 dev->flags & IFF_PROMISC ? "entered" : "left");
5754 if (audit_enabled) {
5755 current_uid_gid(&uid, &gid);
5756 audit_log(current->audit_context, GFP_ATOMIC,
5757 AUDIT_ANOM_PROMISCUOUS,
5758 "dev=%s prom=%d old_prom=%d auid=%u uid=%u gid=%u ses=%u",
5759 dev->name, (dev->flags & IFF_PROMISC),
5760 (old_flags & IFF_PROMISC),
5761 from_kuid(&init_user_ns, audit_get_loginuid(current)),
5762 from_kuid(&init_user_ns, uid),
5763 from_kgid(&init_user_ns, gid),
5764 audit_get_sessionid(current));
5767 dev_change_rx_flags(dev, IFF_PROMISC);
5770 __dev_notify_flags(dev, old_flags, IFF_PROMISC);
5775 * dev_set_promiscuity - update promiscuity count on a device
5779 * Add or remove promiscuity from a device. While the count in the device
5780 * remains above zero the interface remains promiscuous. Once it hits zero
5781 * the device reverts back to normal filtering operation. A negative inc
5782 * value is used to drop promiscuity on the device.
5783 * Return 0 if successful or a negative errno code on error.
5785 int dev_set_promiscuity(struct net_device *dev, int inc)
5787 unsigned int old_flags = dev->flags;
5790 err = __dev_set_promiscuity(dev, inc, true);
5793 if (dev->flags != old_flags)
5794 dev_set_rx_mode(dev);
5797 EXPORT_SYMBOL(dev_set_promiscuity);
5799 static int __dev_set_allmulti(struct net_device *dev, int inc, bool notify)
5801 unsigned int old_flags = dev->flags, old_gflags = dev->gflags;
5805 dev->flags |= IFF_ALLMULTI;
5806 dev->allmulti += inc;
5807 if (dev->allmulti == 0) {
5810 * If inc causes overflow, untouch allmulti and return error.
5813 dev->flags &= ~IFF_ALLMULTI;
5815 dev->allmulti -= inc;
5816 pr_warn("%s: allmulti touches roof, set allmulti failed. allmulti feature of device might be broken.\n",
5821 if (dev->flags ^ old_flags) {
5822 dev_change_rx_flags(dev, IFF_ALLMULTI);
5823 dev_set_rx_mode(dev);
5825 __dev_notify_flags(dev, old_flags,
5826 dev->gflags ^ old_gflags);
5832 * dev_set_allmulti - update allmulti count on a device
5836 * Add or remove reception of all multicast frames to a device. While the
5837 * count in the device remains above zero the interface remains listening
5838 * to all interfaces. Once it hits zero the device reverts back to normal
5839 * filtering operation. A negative @inc value is used to drop the counter
5840 * when releasing a resource needing all multicasts.
5841 * Return 0 if successful or a negative errno code on error.
5844 int dev_set_allmulti(struct net_device *dev, int inc)
5846 return __dev_set_allmulti(dev, inc, true);
5848 EXPORT_SYMBOL(dev_set_allmulti);
5851 * Upload unicast and multicast address lists to device and
5852 * configure RX filtering. When the device doesn't support unicast
5853 * filtering it is put in promiscuous mode while unicast addresses
5856 void __dev_set_rx_mode(struct net_device *dev)
5858 const struct net_device_ops *ops = dev->netdev_ops;
5860 /* dev_open will call this function so the list will stay sane. */
5861 if (!(dev->flags&IFF_UP))
5864 if (!netif_device_present(dev))
5867 if (!(dev->priv_flags & IFF_UNICAST_FLT)) {
5868 /* Unicast addresses changes may only happen under the rtnl,
5869 * therefore calling __dev_set_promiscuity here is safe.
5871 if (!netdev_uc_empty(dev) && !dev->uc_promisc) {
5872 __dev_set_promiscuity(dev, 1, false);
5873 dev->uc_promisc = true;
5874 } else if (netdev_uc_empty(dev) && dev->uc_promisc) {
5875 __dev_set_promiscuity(dev, -1, false);
5876 dev->uc_promisc = false;
5880 if (ops->ndo_set_rx_mode)
5881 ops->ndo_set_rx_mode(dev);
5884 void dev_set_rx_mode(struct net_device *dev)
5886 netif_addr_lock_bh(dev);
5887 __dev_set_rx_mode(dev);
5888 netif_addr_unlock_bh(dev);
5892 * dev_get_flags - get flags reported to userspace
5895 * Get the combination of flag bits exported through APIs to userspace.
5897 unsigned int dev_get_flags(const struct net_device *dev)
5901 flags = (dev->flags & ~(IFF_PROMISC |
5906 (dev->gflags & (IFF_PROMISC |
5909 if (netif_running(dev)) {
5910 if (netif_oper_up(dev))
5911 flags |= IFF_RUNNING;
5912 if (netif_carrier_ok(dev))
5913 flags |= IFF_LOWER_UP;
5914 if (netif_dormant(dev))
5915 flags |= IFF_DORMANT;
5920 EXPORT_SYMBOL(dev_get_flags);
5922 int __dev_change_flags(struct net_device *dev, unsigned int flags)
5924 unsigned int old_flags = dev->flags;
5930 * Set the flags on our device.
5933 dev->flags = (flags & (IFF_DEBUG | IFF_NOTRAILERS | IFF_NOARP |
5934 IFF_DYNAMIC | IFF_MULTICAST | IFF_PORTSEL |
5936 (dev->flags & (IFF_UP | IFF_VOLATILE | IFF_PROMISC |
5940 * Load in the correct multicast list now the flags have changed.
5943 if ((old_flags ^ flags) & IFF_MULTICAST)
5944 dev_change_rx_flags(dev, IFF_MULTICAST);
5946 dev_set_rx_mode(dev);
5949 * Have we downed the interface. We handle IFF_UP ourselves
5950 * according to user attempts to set it, rather than blindly
5955 if ((old_flags ^ flags) & IFF_UP)
5956 ret = ((old_flags & IFF_UP) ? __dev_close : __dev_open)(dev);
5958 if ((flags ^ dev->gflags) & IFF_PROMISC) {
5959 int inc = (flags & IFF_PROMISC) ? 1 : -1;
5960 unsigned int old_flags = dev->flags;
5962 dev->gflags ^= IFF_PROMISC;
5964 if (__dev_set_promiscuity(dev, inc, false) >= 0)
5965 if (dev->flags != old_flags)
5966 dev_set_rx_mode(dev);
5969 /* NOTE: order of synchronization of IFF_PROMISC and IFF_ALLMULTI
5970 is important. Some (broken) drivers set IFF_PROMISC, when
5971 IFF_ALLMULTI is requested not asking us and not reporting.
5973 if ((flags ^ dev->gflags) & IFF_ALLMULTI) {
5974 int inc = (flags & IFF_ALLMULTI) ? 1 : -1;
5976 dev->gflags ^= IFF_ALLMULTI;
5977 __dev_set_allmulti(dev, inc, false);
5983 void __dev_notify_flags(struct net_device *dev, unsigned int old_flags,
5984 unsigned int gchanges)
5986 unsigned int changes = dev->flags ^ old_flags;
5989 rtmsg_ifinfo(RTM_NEWLINK, dev, gchanges, GFP_ATOMIC);
5991 if (changes & IFF_UP) {
5992 if (dev->flags & IFF_UP)
5993 call_netdevice_notifiers(NETDEV_UP, dev);
5995 call_netdevice_notifiers(NETDEV_DOWN, dev);
5998 if (dev->flags & IFF_UP &&
5999 (changes & ~(IFF_UP | IFF_PROMISC | IFF_ALLMULTI | IFF_VOLATILE))) {
6000 struct netdev_notifier_change_info change_info;
6002 change_info.flags_changed = changes;
6003 call_netdevice_notifiers_info(NETDEV_CHANGE, dev,
6009 * dev_change_flags - change device settings
6011 * @flags: device state flags
6013 * Change settings on device based state flags. The flags are
6014 * in the userspace exported format.
6016 int dev_change_flags(struct net_device *dev, unsigned int flags)
6019 unsigned int changes, old_flags = dev->flags, old_gflags = dev->gflags;
6021 ret = __dev_change_flags(dev, flags);
6025 changes = (old_flags ^ dev->flags) | (old_gflags ^ dev->gflags);
6026 __dev_notify_flags(dev, old_flags, changes);
6029 EXPORT_SYMBOL(dev_change_flags);
6031 static int __dev_set_mtu(struct net_device *dev, int new_mtu)
6033 const struct net_device_ops *ops = dev->netdev_ops;
6035 if (ops->ndo_change_mtu)
6036 return ops->ndo_change_mtu(dev, new_mtu);
6043 * dev_set_mtu - Change maximum transfer unit
6045 * @new_mtu: new transfer unit
6047 * Change the maximum transfer size of the network device.
6049 int dev_set_mtu(struct net_device *dev, int new_mtu)
6053 if (new_mtu == dev->mtu)
6056 /* MTU must be positive. */
6060 if (!netif_device_present(dev))
6063 err = call_netdevice_notifiers(NETDEV_PRECHANGEMTU, dev);
6064 err = notifier_to_errno(err);
6068 orig_mtu = dev->mtu;
6069 err = __dev_set_mtu(dev, new_mtu);
6072 err = call_netdevice_notifiers(NETDEV_CHANGEMTU, dev);
6073 err = notifier_to_errno(err);
6075 /* setting mtu back and notifying everyone again,
6076 * so that they have a chance to revert changes.
6078 __dev_set_mtu(dev, orig_mtu);
6079 call_netdevice_notifiers(NETDEV_CHANGEMTU, dev);
6084 EXPORT_SYMBOL(dev_set_mtu);
6087 * dev_set_group - Change group this device belongs to
6089 * @new_group: group this device should belong to
6091 void dev_set_group(struct net_device *dev, int new_group)
6093 dev->group = new_group;
6095 EXPORT_SYMBOL(dev_set_group);
6098 * dev_set_mac_address - Change Media Access Control Address
6102 * Change the hardware (MAC) address of the device
6104 int dev_set_mac_address(struct net_device *dev, struct sockaddr *sa)
6106 const struct net_device_ops *ops = dev->netdev_ops;
6109 if (!ops->ndo_set_mac_address)
6111 if (sa->sa_family != dev->type)
6113 if (!netif_device_present(dev))
6115 err = ops->ndo_set_mac_address(dev, sa);
6118 dev->addr_assign_type = NET_ADDR_SET;
6119 call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
6120 add_device_randomness(dev->dev_addr, dev->addr_len);
6123 EXPORT_SYMBOL(dev_set_mac_address);
6126 * dev_change_carrier - Change device carrier
6128 * @new_carrier: new value
6130 * Change device carrier
6132 int dev_change_carrier(struct net_device *dev, bool new_carrier)
6134 const struct net_device_ops *ops = dev->netdev_ops;
6136 if (!ops->ndo_change_carrier)
6138 if (!netif_device_present(dev))
6140 return ops->ndo_change_carrier(dev, new_carrier);
6142 EXPORT_SYMBOL(dev_change_carrier);
6145 * dev_get_phys_port_id - Get device physical port ID
6149 * Get device physical port ID
6151 int dev_get_phys_port_id(struct net_device *dev,
6152 struct netdev_phys_item_id *ppid)
6154 const struct net_device_ops *ops = dev->netdev_ops;
6156 if (!ops->ndo_get_phys_port_id)
6158 return ops->ndo_get_phys_port_id(dev, ppid);
6160 EXPORT_SYMBOL(dev_get_phys_port_id);
6163 * dev_get_phys_port_name - Get device physical port name
6167 * Get device physical port name
6169 int dev_get_phys_port_name(struct net_device *dev,
6170 char *name, size_t len)
6172 const struct net_device_ops *ops = dev->netdev_ops;
6174 if (!ops->ndo_get_phys_port_name)
6176 return ops->ndo_get_phys_port_name(dev, name, len);
6178 EXPORT_SYMBOL(dev_get_phys_port_name);
6181 * dev_change_proto_down - update protocol port state information
6183 * @proto_down: new value
6185 * This info can be used by switch drivers to set the phys state of the
6188 int dev_change_proto_down(struct net_device *dev, bool proto_down)
6190 const struct net_device_ops *ops = dev->netdev_ops;
6192 if (!ops->ndo_change_proto_down)
6194 if (!netif_device_present(dev))
6196 return ops->ndo_change_proto_down(dev, proto_down);
6198 EXPORT_SYMBOL(dev_change_proto_down);
6201 * dev_new_index - allocate an ifindex
6202 * @net: the applicable net namespace
6204 * Returns a suitable unique value for a new device interface
6205 * number. The caller must hold the rtnl semaphore or the
6206 * dev_base_lock to be sure it remains unique.
6208 static int dev_new_index(struct net *net)
6210 int ifindex = net->ifindex;
6214 if (!__dev_get_by_index(net, ifindex))
6215 return net->ifindex = ifindex;
6219 /* Delayed registration/unregisteration */
6220 static LIST_HEAD(net_todo_list);
6221 DECLARE_WAIT_QUEUE_HEAD(netdev_unregistering_wq);
6223 static void net_set_todo(struct net_device *dev)
6225 list_add_tail(&dev->todo_list, &net_todo_list);
6226 dev_net(dev)->dev_unreg_count++;
6229 static void rollback_registered_many(struct list_head *head)
6231 struct net_device *dev, *tmp;
6232 LIST_HEAD(close_head);
6234 BUG_ON(dev_boot_phase);
6237 list_for_each_entry_safe(dev, tmp, head, unreg_list) {
6238 /* Some devices call without registering
6239 * for initialization unwind. Remove those
6240 * devices and proceed with the remaining.
6242 if (dev->reg_state == NETREG_UNINITIALIZED) {
6243 pr_debug("unregister_netdevice: device %s/%p never was registered\n",
6247 list_del(&dev->unreg_list);
6250 dev->dismantle = true;
6251 BUG_ON(dev->reg_state != NETREG_REGISTERED);
6254 /* If device is running, close it first. */
6255 list_for_each_entry(dev, head, unreg_list)
6256 list_add_tail(&dev->close_list, &close_head);
6257 dev_close_many(&close_head, true);
6259 list_for_each_entry(dev, head, unreg_list) {
6260 /* And unlink it from device chain. */
6261 unlist_netdevice(dev);
6263 dev->reg_state = NETREG_UNREGISTERING;
6264 on_each_cpu(flush_backlog, dev, 1);
6269 list_for_each_entry(dev, head, unreg_list) {
6270 struct sk_buff *skb = NULL;
6272 /* Shutdown queueing discipline. */
6276 /* Notify protocols, that we are about to destroy
6277 this device. They should clean all the things.
6279 call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
6281 if (!dev->rtnl_link_ops ||
6282 dev->rtnl_link_state == RTNL_LINK_INITIALIZED)
6283 skb = rtmsg_ifinfo_build_skb(RTM_DELLINK, dev, ~0U,
6287 * Flush the unicast and multicast chains
6292 if (dev->netdev_ops->ndo_uninit)
6293 dev->netdev_ops->ndo_uninit(dev);
6296 rtmsg_ifinfo_send(skb, dev, GFP_KERNEL);
6298 /* Notifier chain MUST detach us all upper devices. */
6299 WARN_ON(netdev_has_any_upper_dev(dev));
6301 /* Remove entries from kobject tree */
6302 netdev_unregister_kobject(dev);
6304 /* Remove XPS queueing entries */
6305 netif_reset_xps_queues_gt(dev, 0);
6311 list_for_each_entry(dev, head, unreg_list)
6315 static void rollback_registered(struct net_device *dev)
6319 list_add(&dev->unreg_list, &single);
6320 rollback_registered_many(&single);
6324 static netdev_features_t netdev_sync_upper_features(struct net_device *lower,
6325 struct net_device *upper, netdev_features_t features)
6327 netdev_features_t upper_disables = NETIF_F_UPPER_DISABLES;
6328 netdev_features_t feature;
6331 for_each_netdev_feature(&upper_disables, feature_bit) {
6332 feature = __NETIF_F_BIT(feature_bit);
6333 if (!(upper->wanted_features & feature)
6334 && (features & feature)) {
6335 netdev_dbg(lower, "Dropping feature %pNF, upper dev %s has it off.\n",
6336 &feature, upper->name);
6337 features &= ~feature;
6344 static void netdev_sync_lower_features(struct net_device *upper,
6345 struct net_device *lower, netdev_features_t features)
6347 netdev_features_t upper_disables = NETIF_F_UPPER_DISABLES;
6348 netdev_features_t feature;
6351 for_each_netdev_feature(&upper_disables, feature_bit) {
6352 feature = __NETIF_F_BIT(feature_bit);
6353 if (!(features & feature) && (lower->features & feature)) {
6354 netdev_dbg(upper, "Disabling feature %pNF on lower dev %s.\n",
6355 &feature, lower->name);
6356 lower->wanted_features &= ~feature;
6357 netdev_update_features(lower);
6359 if (unlikely(lower->features & feature))
6360 netdev_WARN(upper, "failed to disable %pNF on %s!\n",
6361 &feature, lower->name);
6366 static netdev_features_t netdev_fix_features(struct net_device *dev,
6367 netdev_features_t features)
6369 /* Fix illegal checksum combinations */
6370 if ((features & NETIF_F_HW_CSUM) &&
6371 (features & (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))) {
6372 netdev_warn(dev, "mixed HW and IP checksum settings.\n");
6373 features &= ~(NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM);
6376 /* TSO requires that SG is present as well. */
6377 if ((features & NETIF_F_ALL_TSO) && !(features & NETIF_F_SG)) {
6378 netdev_dbg(dev, "Dropping TSO features since no SG feature.\n");
6379 features &= ~NETIF_F_ALL_TSO;
6382 if ((features & NETIF_F_TSO) && !(features & NETIF_F_HW_CSUM) &&
6383 !(features & NETIF_F_IP_CSUM)) {
6384 netdev_dbg(dev, "Dropping TSO features since no CSUM feature.\n");
6385 features &= ~NETIF_F_TSO;
6386 features &= ~NETIF_F_TSO_ECN;
6389 if ((features & NETIF_F_TSO6) && !(features & NETIF_F_HW_CSUM) &&
6390 !(features & NETIF_F_IPV6_CSUM)) {
6391 netdev_dbg(dev, "Dropping TSO6 features since no CSUM feature.\n");
6392 features &= ~NETIF_F_TSO6;
6395 /* TSO ECN requires that TSO is present as well. */
6396 if ((features & NETIF_F_ALL_TSO) == NETIF_F_TSO_ECN)
6397 features &= ~NETIF_F_TSO_ECN;
6399 /* Software GSO depends on SG. */
6400 if ((features & NETIF_F_GSO) && !(features & NETIF_F_SG)) {
6401 netdev_dbg(dev, "Dropping NETIF_F_GSO since no SG feature.\n");
6402 features &= ~NETIF_F_GSO;
6405 /* UFO needs SG and checksumming */
6406 if (features & NETIF_F_UFO) {
6407 /* maybe split UFO into V4 and V6? */
6408 if (!((features & NETIF_F_GEN_CSUM) ||
6409 (features & (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))
6410 == (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))) {
6412 "Dropping NETIF_F_UFO since no checksum offload features.\n");
6413 features &= ~NETIF_F_UFO;
6416 if (!(features & NETIF_F_SG)) {
6418 "Dropping NETIF_F_UFO since no NETIF_F_SG feature.\n");
6419 features &= ~NETIF_F_UFO;
6423 #ifdef CONFIG_NET_RX_BUSY_POLL
6424 if (dev->netdev_ops->ndo_busy_poll)
6425 features |= NETIF_F_BUSY_POLL;
6428 features &= ~NETIF_F_BUSY_POLL;
6433 int __netdev_update_features(struct net_device *dev)
6435 struct net_device *upper, *lower;
6436 netdev_features_t features;
6437 struct list_head *iter;
6442 features = netdev_get_wanted_features(dev);
6444 if (dev->netdev_ops->ndo_fix_features)
6445 features = dev->netdev_ops->ndo_fix_features(dev, features);
6447 /* driver might be less strict about feature dependencies */
6448 features = netdev_fix_features(dev, features);
6450 /* some features can't be enabled if they're off an an upper device */
6451 netdev_for_each_upper_dev_rcu(dev, upper, iter)
6452 features = netdev_sync_upper_features(dev, upper, features);
6454 if (dev->features == features)
6457 netdev_dbg(dev, "Features changed: %pNF -> %pNF\n",
6458 &dev->features, &features);
6460 if (dev->netdev_ops->ndo_set_features)
6461 err = dev->netdev_ops->ndo_set_features(dev, features);
6465 if (unlikely(err < 0)) {
6467 "set_features() failed (%d); wanted %pNF, left %pNF\n",
6468 err, &features, &dev->features);
6469 /* return non-0 since some features might have changed and
6470 * it's better to fire a spurious notification than miss it
6476 /* some features must be disabled on lower devices when disabled
6477 * on an upper device (think: bonding master or bridge)
6479 netdev_for_each_lower_dev(dev, lower, iter)
6480 netdev_sync_lower_features(dev, lower, features);
6483 dev->features = features;
6485 return err < 0 ? 0 : 1;
6489 * netdev_update_features - recalculate device features
6490 * @dev: the device to check
6492 * Recalculate dev->features set and send notifications if it
6493 * has changed. Should be called after driver or hardware dependent
6494 * conditions might have changed that influence the features.
6496 void netdev_update_features(struct net_device *dev)
6498 if (__netdev_update_features(dev))
6499 netdev_features_change(dev);
6501 EXPORT_SYMBOL(netdev_update_features);
6504 * netdev_change_features - recalculate device features
6505 * @dev: the device to check
6507 * Recalculate dev->features set and send notifications even
6508 * if they have not changed. Should be called instead of
6509 * netdev_update_features() if also dev->vlan_features might
6510 * have changed to allow the changes to be propagated to stacked
6513 void netdev_change_features(struct net_device *dev)
6515 __netdev_update_features(dev);
6516 netdev_features_change(dev);
6518 EXPORT_SYMBOL(netdev_change_features);
6521 * netif_stacked_transfer_operstate - transfer operstate
6522 * @rootdev: the root or lower level device to transfer state from
6523 * @dev: the device to transfer operstate to
6525 * Transfer operational state from root to device. This is normally
6526 * called when a stacking relationship exists between the root
6527 * device and the device(a leaf device).
6529 void netif_stacked_transfer_operstate(const struct net_device *rootdev,
6530 struct net_device *dev)
6532 if (rootdev->operstate == IF_OPER_DORMANT)
6533 netif_dormant_on(dev);
6535 netif_dormant_off(dev);
6537 if (netif_carrier_ok(rootdev)) {
6538 if (!netif_carrier_ok(dev))
6539 netif_carrier_on(dev);
6541 if (netif_carrier_ok(dev))
6542 netif_carrier_off(dev);
6545 EXPORT_SYMBOL(netif_stacked_transfer_operstate);
6548 static int netif_alloc_rx_queues(struct net_device *dev)
6550 unsigned int i, count = dev->num_rx_queues;
6551 struct netdev_rx_queue *rx;
6552 size_t sz = count * sizeof(*rx);
6556 rx = kzalloc(sz, GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT);
6564 for (i = 0; i < count; i++)
6570 static void netdev_init_one_queue(struct net_device *dev,
6571 struct netdev_queue *queue, void *_unused)
6573 /* Initialize queue lock */
6574 spin_lock_init(&queue->_xmit_lock);
6575 netdev_set_xmit_lockdep_class(&queue->_xmit_lock, dev->type);
6576 queue->xmit_lock_owner = -1;
6577 netdev_queue_numa_node_write(queue, NUMA_NO_NODE);
6580 dql_init(&queue->dql, HZ);
6584 static void netif_free_tx_queues(struct net_device *dev)
6589 static int netif_alloc_netdev_queues(struct net_device *dev)
6591 unsigned int count = dev->num_tx_queues;
6592 struct netdev_queue *tx;
6593 size_t sz = count * sizeof(*tx);
6595 if (count < 1 || count > 0xffff)
6598 tx = kzalloc(sz, GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT);
6606 netdev_for_each_tx_queue(dev, netdev_init_one_queue, NULL);
6607 spin_lock_init(&dev->tx_global_lock);
6612 void netif_tx_stop_all_queues(struct net_device *dev)
6616 for (i = 0; i < dev->num_tx_queues; i++) {
6617 struct netdev_queue *txq = netdev_get_tx_queue(dev, i);
6618 netif_tx_stop_queue(txq);
6621 EXPORT_SYMBOL(netif_tx_stop_all_queues);
6624 * register_netdevice - register a network device
6625 * @dev: device to register
6627 * Take a completed network device structure and add it to the kernel
6628 * interfaces. A %NETDEV_REGISTER message is sent to the netdev notifier
6629 * chain. 0 is returned on success. A negative errno code is returned
6630 * on a failure to set up the device, or if the name is a duplicate.
6632 * Callers must hold the rtnl semaphore. You may want
6633 * register_netdev() instead of this.
6636 * The locking appears insufficient to guarantee two parallel registers
6637 * will not get the same name.
6640 int register_netdevice(struct net_device *dev)
6643 struct net *net = dev_net(dev);
6645 BUG_ON(dev_boot_phase);
6650 /* When net_device's are persistent, this will be fatal. */
6651 BUG_ON(dev->reg_state != NETREG_UNINITIALIZED);
6654 spin_lock_init(&dev->addr_list_lock);
6655 netdev_set_addr_lockdep_class(dev);
6657 ret = dev_get_valid_name(net, dev, dev->name);
6661 /* Init, if this function is available */
6662 if (dev->netdev_ops->ndo_init) {
6663 ret = dev->netdev_ops->ndo_init(dev);
6671 if (((dev->hw_features | dev->features) &
6672 NETIF_F_HW_VLAN_CTAG_FILTER) &&
6673 (!dev->netdev_ops->ndo_vlan_rx_add_vid ||
6674 !dev->netdev_ops->ndo_vlan_rx_kill_vid)) {
6675 netdev_WARN(dev, "Buggy VLAN acceleration in driver!\n");
6682 dev->ifindex = dev_new_index(net);
6683 else if (__dev_get_by_index(net, dev->ifindex))
6686 /* Transfer changeable features to wanted_features and enable
6687 * software offloads (GSO and GRO).
6689 dev->hw_features |= NETIF_F_SOFT_FEATURES;
6690 dev->features |= NETIF_F_SOFT_FEATURES;
6691 dev->wanted_features = dev->features & dev->hw_features;
6693 if (!(dev->flags & IFF_LOOPBACK)) {
6694 dev->hw_features |= NETIF_F_NOCACHE_COPY;
6697 /* Make NETIF_F_HIGHDMA inheritable to VLAN devices.
6699 dev->vlan_features |= NETIF_F_HIGHDMA;
6701 /* Make NETIF_F_SG inheritable to tunnel devices.
6703 dev->hw_enc_features |= NETIF_F_SG;
6705 /* Make NETIF_F_SG inheritable to MPLS.
6707 dev->mpls_features |= NETIF_F_SG;
6709 ret = call_netdevice_notifiers(NETDEV_POST_INIT, dev);
6710 ret = notifier_to_errno(ret);
6714 ret = netdev_register_kobject(dev);
6717 dev->reg_state = NETREG_REGISTERED;
6719 __netdev_update_features(dev);
6722 * Default initial state at registry is that the
6723 * device is present.
6726 set_bit(__LINK_STATE_PRESENT, &dev->state);
6728 linkwatch_init_dev(dev);
6730 dev_init_scheduler(dev);
6732 list_netdevice(dev);
6733 add_device_randomness(dev->dev_addr, dev->addr_len);
6735 /* If the device has permanent device address, driver should
6736 * set dev_addr and also addr_assign_type should be set to
6737 * NET_ADDR_PERM (default value).
6739 if (dev->addr_assign_type == NET_ADDR_PERM)
6740 memcpy(dev->perm_addr, dev->dev_addr, dev->addr_len);
6742 /* Notify protocols, that a new device appeared. */
6743 ret = call_netdevice_notifiers(NETDEV_REGISTER, dev);
6744 ret = notifier_to_errno(ret);
6746 rollback_registered(dev);
6747 dev->reg_state = NETREG_UNREGISTERED;
6750 * Prevent userspace races by waiting until the network
6751 * device is fully setup before sending notifications.
6753 if (!dev->rtnl_link_ops ||
6754 dev->rtnl_link_state == RTNL_LINK_INITIALIZED)
6755 rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U, GFP_KERNEL);
6761 if (dev->netdev_ops->ndo_uninit)
6762 dev->netdev_ops->ndo_uninit(dev);
6765 EXPORT_SYMBOL(register_netdevice);
6768 * init_dummy_netdev - init a dummy network device for NAPI
6769 * @dev: device to init
6771 * This takes a network device structure and initialize the minimum
6772 * amount of fields so it can be used to schedule NAPI polls without
6773 * registering a full blown interface. This is to be used by drivers
6774 * that need to tie several hardware interfaces to a single NAPI
6775 * poll scheduler due to HW limitations.
6777 int init_dummy_netdev(struct net_device *dev)
6779 /* Clear everything. Note we don't initialize spinlocks
6780 * are they aren't supposed to be taken by any of the
6781 * NAPI code and this dummy netdev is supposed to be
6782 * only ever used for NAPI polls
6784 memset(dev, 0, sizeof(struct net_device));
6786 /* make sure we BUG if trying to hit standard
6787 * register/unregister code path
6789 dev->reg_state = NETREG_DUMMY;
6791 /* NAPI wants this */
6792 INIT_LIST_HEAD(&dev->napi_list);
6794 /* a dummy interface is started by default */
6795 set_bit(__LINK_STATE_PRESENT, &dev->state);
6796 set_bit(__LINK_STATE_START, &dev->state);
6798 /* Note : We dont allocate pcpu_refcnt for dummy devices,
6799 * because users of this 'device' dont need to change
6805 EXPORT_SYMBOL_GPL(init_dummy_netdev);
6809 * register_netdev - register a network device
6810 * @dev: device to register
6812 * Take a completed network device structure and add it to the kernel
6813 * interfaces. A %NETDEV_REGISTER message is sent to the netdev notifier
6814 * chain. 0 is returned on success. A negative errno code is returned
6815 * on a failure to set up the device, or if the name is a duplicate.
6817 * This is a wrapper around register_netdevice that takes the rtnl semaphore
6818 * and expands the device name if you passed a format string to
6821 int register_netdev(struct net_device *dev)
6826 err = register_netdevice(dev);
6830 EXPORT_SYMBOL(register_netdev);
6832 int netdev_refcnt_read(const struct net_device *dev)
6836 for_each_possible_cpu(i)
6837 refcnt += *per_cpu_ptr(dev->pcpu_refcnt, i);
6840 EXPORT_SYMBOL(netdev_refcnt_read);
6843 * netdev_wait_allrefs - wait until all references are gone.
6844 * @dev: target net_device
6846 * This is called when unregistering network devices.
6848 * Any protocol or device that holds a reference should register
6849 * for netdevice notification, and cleanup and put back the
6850 * reference if they receive an UNREGISTER event.
6851 * We can get stuck here if buggy protocols don't correctly
6854 static void netdev_wait_allrefs(struct net_device *dev)
6856 unsigned long rebroadcast_time, warning_time;
6859 linkwatch_forget_dev(dev);
6861 rebroadcast_time = warning_time = jiffies;
6862 refcnt = netdev_refcnt_read(dev);
6864 while (refcnt != 0) {
6865 if (time_after(jiffies, rebroadcast_time + 1 * HZ)) {
6868 /* Rebroadcast unregister notification */
6869 call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
6875 call_netdevice_notifiers(NETDEV_UNREGISTER_FINAL, dev);
6876 if (test_bit(__LINK_STATE_LINKWATCH_PENDING,
6878 /* We must not have linkwatch events
6879 * pending on unregister. If this
6880 * happens, we simply run the queue
6881 * unscheduled, resulting in a noop
6884 linkwatch_run_queue();
6889 rebroadcast_time = jiffies;
6894 refcnt = netdev_refcnt_read(dev);
6896 if (time_after(jiffies, warning_time + 10 * HZ)) {
6897 pr_emerg("unregister_netdevice: waiting for %s to become free. Usage count = %d\n",
6899 warning_time = jiffies;
6908 * register_netdevice(x1);
6909 * register_netdevice(x2);
6911 * unregister_netdevice(y1);
6912 * unregister_netdevice(y2);
6918 * We are invoked by rtnl_unlock().
6919 * This allows us to deal with problems:
6920 * 1) We can delete sysfs objects which invoke hotplug
6921 * without deadlocking with linkwatch via keventd.
6922 * 2) Since we run with the RTNL semaphore not held, we can sleep
6923 * safely in order to wait for the netdev refcnt to drop to zero.
6925 * We must not return until all unregister events added during
6926 * the interval the lock was held have been completed.
6928 void netdev_run_todo(void)
6930 struct list_head list;
6932 /* Snapshot list, allow later requests */
6933 list_replace_init(&net_todo_list, &list);
6938 /* Wait for rcu callbacks to finish before next phase */
6939 if (!list_empty(&list))
6942 while (!list_empty(&list)) {
6943 struct net_device *dev
6944 = list_first_entry(&list, struct net_device, todo_list);
6945 list_del(&dev->todo_list);
6948 call_netdevice_notifiers(NETDEV_UNREGISTER_FINAL, dev);
6951 if (unlikely(dev->reg_state != NETREG_UNREGISTERING)) {
6952 pr_err("network todo '%s' but state %d\n",
6953 dev->name, dev->reg_state);
6958 dev->reg_state = NETREG_UNREGISTERED;
6960 netdev_wait_allrefs(dev);
6963 BUG_ON(netdev_refcnt_read(dev));
6964 BUG_ON(!list_empty(&dev->ptype_all));
6965 BUG_ON(!list_empty(&dev->ptype_specific));
6966 WARN_ON(rcu_access_pointer(dev->ip_ptr));
6967 WARN_ON(rcu_access_pointer(dev->ip6_ptr));
6968 WARN_ON(dev->dn_ptr);
6970 if (dev->destructor)
6971 dev->destructor(dev);
6973 /* Report a network device has been unregistered */
6975 dev_net(dev)->dev_unreg_count--;
6977 wake_up(&netdev_unregistering_wq);
6979 /* Free network device */
6980 kobject_put(&dev->dev.kobj);
6984 /* Convert net_device_stats to rtnl_link_stats64. They have the same
6985 * fields in the same order, with only the type differing.
6987 void netdev_stats_to_stats64(struct rtnl_link_stats64 *stats64,
6988 const struct net_device_stats *netdev_stats)
6990 #if BITS_PER_LONG == 64
6991 BUILD_BUG_ON(sizeof(*stats64) != sizeof(*netdev_stats));
6992 memcpy(stats64, netdev_stats, sizeof(*stats64));
6994 size_t i, n = sizeof(*stats64) / sizeof(u64);
6995 const unsigned long *src = (const unsigned long *)netdev_stats;
6996 u64 *dst = (u64 *)stats64;
6998 BUILD_BUG_ON(sizeof(*netdev_stats) / sizeof(unsigned long) !=
6999 sizeof(*stats64) / sizeof(u64));
7000 for (i = 0; i < n; i++)
7004 EXPORT_SYMBOL(netdev_stats_to_stats64);
7007 * dev_get_stats - get network device statistics
7008 * @dev: device to get statistics from
7009 * @storage: place to store stats
7011 * Get network statistics from device. Return @storage.
7012 * The device driver may provide its own method by setting
7013 * dev->netdev_ops->get_stats64 or dev->netdev_ops->get_stats;
7014 * otherwise the internal statistics structure is used.
7016 struct rtnl_link_stats64 *dev_get_stats(struct net_device *dev,
7017 struct rtnl_link_stats64 *storage)
7019 const struct net_device_ops *ops = dev->netdev_ops;
7021 if (ops->ndo_get_stats64) {
7022 memset(storage, 0, sizeof(*storage));
7023 ops->ndo_get_stats64(dev, storage);
7024 } else if (ops->ndo_get_stats) {
7025 netdev_stats_to_stats64(storage, ops->ndo_get_stats(dev));
7027 netdev_stats_to_stats64(storage, &dev->stats);
7029 storage->rx_dropped += atomic_long_read(&dev->rx_dropped);
7030 storage->tx_dropped += atomic_long_read(&dev->tx_dropped);
7033 EXPORT_SYMBOL(dev_get_stats);
7035 struct netdev_queue *dev_ingress_queue_create(struct net_device *dev)
7037 struct netdev_queue *queue = dev_ingress_queue(dev);
7039 #ifdef CONFIG_NET_CLS_ACT
7042 queue = kzalloc(sizeof(*queue), GFP_KERNEL);
7045 netdev_init_one_queue(dev, queue, NULL);
7046 RCU_INIT_POINTER(queue->qdisc, &noop_qdisc);
7047 queue->qdisc_sleeping = &noop_qdisc;
7048 rcu_assign_pointer(dev->ingress_queue, queue);
7053 static const struct ethtool_ops default_ethtool_ops;
7055 void netdev_set_default_ethtool_ops(struct net_device *dev,
7056 const struct ethtool_ops *ops)
7058 if (dev->ethtool_ops == &default_ethtool_ops)
7059 dev->ethtool_ops = ops;
7061 EXPORT_SYMBOL_GPL(netdev_set_default_ethtool_ops);
7063 void netdev_freemem(struct net_device *dev)
7065 char *addr = (char *)dev - dev->padded;
7071 * alloc_netdev_mqs - allocate network device
7072 * @sizeof_priv: size of private data to allocate space for
7073 * @name: device name format string
7074 * @name_assign_type: origin of device name
7075 * @setup: callback to initialize device
7076 * @txqs: the number of TX subqueues to allocate
7077 * @rxqs: the number of RX subqueues to allocate
7079 * Allocates a struct net_device with private data area for driver use
7080 * and performs basic initialization. Also allocates subqueue structs
7081 * for each queue on the device.
7083 struct net_device *alloc_netdev_mqs(int sizeof_priv, const char *name,
7084 unsigned char name_assign_type,
7085 void (*setup)(struct net_device *),
7086 unsigned int txqs, unsigned int rxqs)
7088 struct net_device *dev;
7090 struct net_device *p;
7092 BUG_ON(strlen(name) >= sizeof(dev->name));
7095 pr_err("alloc_netdev: Unable to allocate device with zero queues\n");
7101 pr_err("alloc_netdev: Unable to allocate device with zero RX queues\n");
7106 alloc_size = sizeof(struct net_device);
7108 /* ensure 32-byte alignment of private area */
7109 alloc_size = ALIGN(alloc_size, NETDEV_ALIGN);
7110 alloc_size += sizeof_priv;
7112 /* ensure 32-byte alignment of whole construct */
7113 alloc_size += NETDEV_ALIGN - 1;
7115 p = kzalloc(alloc_size, GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT);
7117 p = vzalloc(alloc_size);
7121 dev = PTR_ALIGN(p, NETDEV_ALIGN);
7122 dev->padded = (char *)dev - (char *)p;
7124 dev->pcpu_refcnt = alloc_percpu(int);
7125 if (!dev->pcpu_refcnt)
7128 if (dev_addr_init(dev))
7134 dev_net_set(dev, &init_net);
7136 dev->gso_max_size = GSO_MAX_SIZE;
7137 dev->gso_max_segs = GSO_MAX_SEGS;
7138 dev->gso_min_segs = 0;
7140 INIT_LIST_HEAD(&dev->napi_list);
7141 INIT_LIST_HEAD(&dev->unreg_list);
7142 INIT_LIST_HEAD(&dev->close_list);
7143 INIT_LIST_HEAD(&dev->link_watch_list);
7144 INIT_LIST_HEAD(&dev->adj_list.upper);
7145 INIT_LIST_HEAD(&dev->adj_list.lower);
7146 INIT_LIST_HEAD(&dev->all_adj_list.upper);
7147 INIT_LIST_HEAD(&dev->all_adj_list.lower);
7148 INIT_LIST_HEAD(&dev->ptype_all);
7149 INIT_LIST_HEAD(&dev->ptype_specific);
7150 dev->priv_flags = IFF_XMIT_DST_RELEASE | IFF_XMIT_DST_RELEASE_PERM;
7153 if (!dev->tx_queue_len) {
7154 dev->priv_flags |= IFF_NO_QUEUE;
7155 dev->tx_queue_len = 1;
7158 dev->num_tx_queues = txqs;
7159 dev->real_num_tx_queues = txqs;
7160 if (netif_alloc_netdev_queues(dev))
7164 dev->num_rx_queues = rxqs;
7165 dev->real_num_rx_queues = rxqs;
7166 if (netif_alloc_rx_queues(dev))
7170 strcpy(dev->name, name);
7171 dev->name_assign_type = name_assign_type;
7172 dev->group = INIT_NETDEV_GROUP;
7173 if (!dev->ethtool_ops)
7174 dev->ethtool_ops = &default_ethtool_ops;
7176 nf_hook_ingress_init(dev);
7185 free_percpu(dev->pcpu_refcnt);
7187 netdev_freemem(dev);
7190 EXPORT_SYMBOL(alloc_netdev_mqs);
7193 * free_netdev - free network device
7196 * This function does the last stage of destroying an allocated device
7197 * interface. The reference to the device object is released.
7198 * If this is the last reference then it will be freed.
7200 void free_netdev(struct net_device *dev)
7202 struct napi_struct *p, *n;
7204 netif_free_tx_queues(dev);
7209 kfree(rcu_dereference_protected(dev->ingress_queue, 1));
7211 /* Flush device addresses */
7212 dev_addr_flush(dev);
7214 list_for_each_entry_safe(p, n, &dev->napi_list, dev_list)
7217 free_percpu(dev->pcpu_refcnt);
7218 dev->pcpu_refcnt = NULL;
7220 /* Compatibility with error handling in drivers */
7221 if (dev->reg_state == NETREG_UNINITIALIZED) {
7222 netdev_freemem(dev);
7226 BUG_ON(dev->reg_state != NETREG_UNREGISTERED);
7227 dev->reg_state = NETREG_RELEASED;
7229 /* will free via device release */
7230 put_device(&dev->dev);
7232 EXPORT_SYMBOL(free_netdev);
7235 * synchronize_net - Synchronize with packet receive processing
7237 * Wait for packets currently being received to be done.
7238 * Does not block later packets from starting.
7240 void synchronize_net(void)
7243 if (rtnl_is_locked())
7244 synchronize_rcu_expedited();
7248 EXPORT_SYMBOL(synchronize_net);
7251 * unregister_netdevice_queue - remove device from the kernel
7255 * This function shuts down a device interface and removes it
7256 * from the kernel tables.
7257 * If head not NULL, device is queued to be unregistered later.
7259 * Callers must hold the rtnl semaphore. You may want
7260 * unregister_netdev() instead of this.
7263 void unregister_netdevice_queue(struct net_device *dev, struct list_head *head)
7268 list_move_tail(&dev->unreg_list, head);
7270 rollback_registered(dev);
7271 /* Finish processing unregister after unlock */
7275 EXPORT_SYMBOL(unregister_netdevice_queue);
7278 * unregister_netdevice_many - unregister many devices
7279 * @head: list of devices
7281 * Note: As most callers use a stack allocated list_head,
7282 * we force a list_del() to make sure stack wont be corrupted later.
7284 void unregister_netdevice_many(struct list_head *head)
7286 struct net_device *dev;
7288 if (!list_empty(head)) {
7289 rollback_registered_many(head);
7290 list_for_each_entry(dev, head, unreg_list)
7295 EXPORT_SYMBOL(unregister_netdevice_many);
7298 * unregister_netdev - remove device from the kernel
7301 * This function shuts down a device interface and removes it
7302 * from the kernel tables.
7304 * This is just a wrapper for unregister_netdevice that takes
7305 * the rtnl semaphore. In general you want to use this and not
7306 * unregister_netdevice.
7308 void unregister_netdev(struct net_device *dev)
7311 unregister_netdevice(dev);
7314 EXPORT_SYMBOL(unregister_netdev);
7317 * dev_change_net_namespace - move device to different nethost namespace
7319 * @net: network namespace
7320 * @pat: If not NULL name pattern to try if the current device name
7321 * is already taken in the destination network namespace.
7323 * This function shuts down a device interface and moves it
7324 * to a new network namespace. On success 0 is returned, on
7325 * a failure a netagive errno code is returned.
7327 * Callers must hold the rtnl semaphore.
7330 int dev_change_net_namespace(struct net_device *dev, struct net *net, const char *pat)
7336 /* Don't allow namespace local devices to be moved. */
7338 if (dev->features & NETIF_F_NETNS_LOCAL)
7341 /* Ensure the device has been registrered */
7342 if (dev->reg_state != NETREG_REGISTERED)
7345 /* Get out if there is nothing todo */
7347 if (net_eq(dev_net(dev), net))
7350 /* Pick the destination device name, and ensure
7351 * we can use it in the destination network namespace.
7354 if (__dev_get_by_name(net, dev->name)) {
7355 /* We get here if we can't use the current device name */
7358 if (dev_get_valid_name(net, dev, pat) < 0)
7363 * And now a mini version of register_netdevice unregister_netdevice.
7366 /* If device is running close it first. */
7369 /* And unlink it from device chain */
7371 unlist_netdevice(dev);
7375 /* Shutdown queueing discipline. */
7378 /* Notify protocols, that we are about to destroy
7379 this device. They should clean all the things.
7381 Note that dev->reg_state stays at NETREG_REGISTERED.
7382 This is wanted because this way 8021q and macvlan know
7383 the device is just moving and can keep their slaves up.
7385 call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
7387 call_netdevice_notifiers(NETDEV_UNREGISTER_FINAL, dev);
7388 rtmsg_ifinfo(RTM_DELLINK, dev, ~0U, GFP_KERNEL);
7391 * Flush the unicast and multicast chains
7396 /* Send a netdev-removed uevent to the old namespace */
7397 kobject_uevent(&dev->dev.kobj, KOBJ_REMOVE);
7398 netdev_adjacent_del_links(dev);
7400 /* Actually switch the network namespace */
7401 dev_net_set(dev, net);
7403 /* If there is an ifindex conflict assign a new one */
7404 if (__dev_get_by_index(net, dev->ifindex))
7405 dev->ifindex = dev_new_index(net);
7407 /* Send a netdev-add uevent to the new namespace */
7408 kobject_uevent(&dev->dev.kobj, KOBJ_ADD);
7409 netdev_adjacent_add_links(dev);
7411 /* Fixup kobjects */
7412 err = device_rename(&dev->dev, dev->name);
7415 /* Add the device back in the hashes */
7416 list_netdevice(dev);
7418 /* Notify protocols, that a new device appeared. */
7419 call_netdevice_notifiers(NETDEV_REGISTER, dev);
7422 * Prevent userspace races by waiting until the network
7423 * device is fully setup before sending notifications.
7425 rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U, GFP_KERNEL);
7432 EXPORT_SYMBOL_GPL(dev_change_net_namespace);
7434 static int dev_cpu_callback(struct notifier_block *nfb,
7435 unsigned long action,
7438 struct sk_buff **list_skb;
7439 struct sk_buff *skb;
7440 unsigned int cpu, oldcpu = (unsigned long)ocpu;
7441 struct softnet_data *sd, *oldsd;
7443 if (action != CPU_DEAD && action != CPU_DEAD_FROZEN)
7446 local_irq_disable();
7447 cpu = smp_processor_id();
7448 sd = &per_cpu(softnet_data, cpu);
7449 oldsd = &per_cpu(softnet_data, oldcpu);
7451 /* Find end of our completion_queue. */
7452 list_skb = &sd->completion_queue;
7454 list_skb = &(*list_skb)->next;
7455 /* Append completion queue from offline CPU. */
7456 *list_skb = oldsd->completion_queue;
7457 oldsd->completion_queue = NULL;
7459 /* Append output queue from offline CPU. */
7460 if (oldsd->output_queue) {
7461 *sd->output_queue_tailp = oldsd->output_queue;
7462 sd->output_queue_tailp = oldsd->output_queue_tailp;
7463 oldsd->output_queue = NULL;
7464 oldsd->output_queue_tailp = &oldsd->output_queue;
7466 /* Append NAPI poll list from offline CPU, with one exception :
7467 * process_backlog() must be called by cpu owning percpu backlog.
7468 * We properly handle process_queue & input_pkt_queue later.
7470 while (!list_empty(&oldsd->poll_list)) {
7471 struct napi_struct *napi = list_first_entry(&oldsd->poll_list,
7475 list_del_init(&napi->poll_list);
7476 if (napi->poll == process_backlog)
7479 ____napi_schedule(sd, napi);
7482 raise_softirq_irqoff(NET_TX_SOFTIRQ);
7485 /* Process offline CPU's input_pkt_queue */
7486 while ((skb = __skb_dequeue(&oldsd->process_queue))) {
7488 input_queue_head_incr(oldsd);
7490 while ((skb = skb_dequeue(&oldsd->input_pkt_queue))) {
7492 input_queue_head_incr(oldsd);
7500 * netdev_increment_features - increment feature set by one
7501 * @all: current feature set
7502 * @one: new feature set
7503 * @mask: mask feature set
7505 * Computes a new feature set after adding a device with feature set
7506 * @one to the master device with current feature set @all. Will not
7507 * enable anything that is off in @mask. Returns the new feature set.
7509 netdev_features_t netdev_increment_features(netdev_features_t all,
7510 netdev_features_t one, netdev_features_t mask)
7512 if (mask & NETIF_F_GEN_CSUM)
7513 mask |= NETIF_F_ALL_CSUM;
7514 mask |= NETIF_F_VLAN_CHALLENGED;
7516 all |= one & (NETIF_F_ONE_FOR_ALL|NETIF_F_ALL_CSUM) & mask;
7517 all &= one | ~NETIF_F_ALL_FOR_ALL;
7519 /* If one device supports hw checksumming, set for all. */
7520 if (all & NETIF_F_GEN_CSUM)
7521 all &= ~(NETIF_F_ALL_CSUM & ~NETIF_F_GEN_CSUM);
7525 EXPORT_SYMBOL(netdev_increment_features);
7527 static struct hlist_head * __net_init netdev_create_hash(void)
7530 struct hlist_head *hash;
7532 hash = kmalloc(sizeof(*hash) * NETDEV_HASHENTRIES, GFP_KERNEL);
7534 for (i = 0; i < NETDEV_HASHENTRIES; i++)
7535 INIT_HLIST_HEAD(&hash[i]);
7540 /* Initialize per network namespace state */
7541 static int __net_init netdev_init(struct net *net)
7543 if (net != &init_net)
7544 INIT_LIST_HEAD(&net->dev_base_head);
7546 net->dev_name_head = netdev_create_hash();
7547 if (net->dev_name_head == NULL)
7550 net->dev_index_head = netdev_create_hash();
7551 if (net->dev_index_head == NULL)
7557 kfree(net->dev_name_head);
7563 * netdev_drivername - network driver for the device
7564 * @dev: network device
7566 * Determine network driver for device.
7568 const char *netdev_drivername(const struct net_device *dev)
7570 const struct device_driver *driver;
7571 const struct device *parent;
7572 const char *empty = "";
7574 parent = dev->dev.parent;
7578 driver = parent->driver;
7579 if (driver && driver->name)
7580 return driver->name;
7584 static void __netdev_printk(const char *level, const struct net_device *dev,
7585 struct va_format *vaf)
7587 if (dev && dev->dev.parent) {
7588 dev_printk_emit(level[1] - '0',
7591 dev_driver_string(dev->dev.parent),
7592 dev_name(dev->dev.parent),
7593 netdev_name(dev), netdev_reg_state(dev),
7596 printk("%s%s%s: %pV",
7597 level, netdev_name(dev), netdev_reg_state(dev), vaf);
7599 printk("%s(NULL net_device): %pV", level, vaf);
7603 void netdev_printk(const char *level, const struct net_device *dev,
7604 const char *format, ...)
7606 struct va_format vaf;
7609 va_start(args, format);
7614 __netdev_printk(level, dev, &vaf);
7618 EXPORT_SYMBOL(netdev_printk);
7620 #define define_netdev_printk_level(func, level) \
7621 void func(const struct net_device *dev, const char *fmt, ...) \
7623 struct va_format vaf; \
7626 va_start(args, fmt); \
7631 __netdev_printk(level, dev, &vaf); \
7635 EXPORT_SYMBOL(func);
7637 define_netdev_printk_level(netdev_emerg, KERN_EMERG);
7638 define_netdev_printk_level(netdev_alert, KERN_ALERT);
7639 define_netdev_printk_level(netdev_crit, KERN_CRIT);
7640 define_netdev_printk_level(netdev_err, KERN_ERR);
7641 define_netdev_printk_level(netdev_warn, KERN_WARNING);
7642 define_netdev_printk_level(netdev_notice, KERN_NOTICE);
7643 define_netdev_printk_level(netdev_info, KERN_INFO);
7645 static void __net_exit netdev_exit(struct net *net)
7647 kfree(net->dev_name_head);
7648 kfree(net->dev_index_head);
7651 static struct pernet_operations __net_initdata netdev_net_ops = {
7652 .init = netdev_init,
7653 .exit = netdev_exit,
7656 static void __net_exit default_device_exit(struct net *net)
7658 struct net_device *dev, *aux;
7660 * Push all migratable network devices back to the
7661 * initial network namespace
7664 for_each_netdev_safe(net, dev, aux) {
7666 char fb_name[IFNAMSIZ];
7668 /* Ignore unmoveable devices (i.e. loopback) */
7669 if (dev->features & NETIF_F_NETNS_LOCAL)
7672 /* Leave virtual devices for the generic cleanup */
7673 if (dev->rtnl_link_ops)
7676 /* Push remaining network devices to init_net */
7677 snprintf(fb_name, IFNAMSIZ, "dev%d", dev->ifindex);
7678 err = dev_change_net_namespace(dev, &init_net, fb_name);
7680 pr_emerg("%s: failed to move %s to init_net: %d\n",
7681 __func__, dev->name, err);
7688 static void __net_exit rtnl_lock_unregistering(struct list_head *net_list)
7690 /* Return with the rtnl_lock held when there are no network
7691 * devices unregistering in any network namespace in net_list.
7695 DEFINE_WAIT_FUNC(wait, woken_wake_function);
7697 add_wait_queue(&netdev_unregistering_wq, &wait);
7699 unregistering = false;
7701 list_for_each_entry(net, net_list, exit_list) {
7702 if (net->dev_unreg_count > 0) {
7703 unregistering = true;
7711 wait_woken(&wait, TASK_UNINTERRUPTIBLE, MAX_SCHEDULE_TIMEOUT);
7713 remove_wait_queue(&netdev_unregistering_wq, &wait);
7716 static void __net_exit default_device_exit_batch(struct list_head *net_list)
7718 /* At exit all network devices most be removed from a network
7719 * namespace. Do this in the reverse order of registration.
7720 * Do this across as many network namespaces as possible to
7721 * improve batching efficiency.
7723 struct net_device *dev;
7725 LIST_HEAD(dev_kill_list);
7727 /* To prevent network device cleanup code from dereferencing
7728 * loopback devices or network devices that have been freed
7729 * wait here for all pending unregistrations to complete,
7730 * before unregistring the loopback device and allowing the
7731 * network namespace be freed.
7733 * The netdev todo list containing all network devices
7734 * unregistrations that happen in default_device_exit_batch
7735 * will run in the rtnl_unlock() at the end of
7736 * default_device_exit_batch.
7738 rtnl_lock_unregistering(net_list);
7739 list_for_each_entry(net, net_list, exit_list) {
7740 for_each_netdev_reverse(net, dev) {
7741 if (dev->rtnl_link_ops && dev->rtnl_link_ops->dellink)
7742 dev->rtnl_link_ops->dellink(dev, &dev_kill_list);
7744 unregister_netdevice_queue(dev, &dev_kill_list);
7747 unregister_netdevice_many(&dev_kill_list);
7751 static struct pernet_operations __net_initdata default_device_ops = {
7752 .exit = default_device_exit,
7753 .exit_batch = default_device_exit_batch,
7757 * Initialize the DEV module. At boot time this walks the device list and
7758 * unhooks any devices that fail to initialise (normally hardware not
7759 * present) and leaves us with a valid list of present and active devices.
7764 * This is called single threaded during boot, so no need
7765 * to take the rtnl semaphore.
7767 static int __init net_dev_init(void)
7769 int i, rc = -ENOMEM;
7771 BUG_ON(!dev_boot_phase);
7773 if (dev_proc_init())
7776 if (netdev_kobject_init())
7779 INIT_LIST_HEAD(&ptype_all);
7780 for (i = 0; i < PTYPE_HASH_SIZE; i++)
7781 INIT_LIST_HEAD(&ptype_base[i]);
7783 INIT_LIST_HEAD(&offload_base);
7785 if (register_pernet_subsys(&netdev_net_ops))
7789 * Initialise the packet receive queues.
7792 for_each_possible_cpu(i) {
7793 struct softnet_data *sd = &per_cpu(softnet_data, i);
7795 skb_queue_head_init(&sd->input_pkt_queue);
7796 skb_queue_head_init(&sd->process_queue);
7797 INIT_LIST_HEAD(&sd->poll_list);
7798 sd->output_queue_tailp = &sd->output_queue;
7800 sd->csd.func = rps_trigger_softirq;
7805 sd->backlog.poll = process_backlog;
7806 sd->backlog.weight = weight_p;
7811 /* The loopback device is special if any other network devices
7812 * is present in a network namespace the loopback device must
7813 * be present. Since we now dynamically allocate and free the
7814 * loopback device ensure this invariant is maintained by
7815 * keeping the loopback device as the first device on the
7816 * list of network devices. Ensuring the loopback devices
7817 * is the first device that appears and the last network device
7820 if (register_pernet_device(&loopback_net_ops))
7823 if (register_pernet_device(&default_device_ops))
7826 open_softirq(NET_TX_SOFTIRQ, net_tx_action);
7827 open_softirq(NET_RX_SOFTIRQ, net_rx_action);
7829 hotcpu_notifier(dev_cpu_callback, 0);
7836 subsys_initcall(net_dev_init);