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 <linux/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/sched/mm.h>
85 #include <linux/mutex.h>
86 #include <linux/string.h>
88 #include <linux/socket.h>
89 #include <linux/sockios.h>
90 #include <linux/errno.h>
91 #include <linux/interrupt.h>
92 #include <linux/if_ether.h>
93 #include <linux/netdevice.h>
94 #include <linux/etherdevice.h>
95 #include <linux/ethtool.h>
96 #include <linux/notifier.h>
97 #include <linux/skbuff.h>
98 #include <linux/bpf.h>
99 #include <linux/bpf_trace.h>
100 #include <net/net_namespace.h>
101 #include <net/sock.h>
102 #include <net/busy_poll.h>
103 #include <linux/rtnetlink.h>
104 #include <linux/stat.h>
106 #include <net/dst_metadata.h>
107 #include <net/pkt_sched.h>
108 #include <net/pkt_cls.h>
109 #include <net/checksum.h>
110 #include <net/xfrm.h>
111 #include <linux/highmem.h>
112 #include <linux/init.h>
113 #include <linux/module.h>
114 #include <linux/netpoll.h>
115 #include <linux/rcupdate.h>
116 #include <linux/delay.h>
117 #include <net/iw_handler.h>
118 #include <asm/current.h>
119 #include <linux/audit.h>
120 #include <linux/dmaengine.h>
121 #include <linux/err.h>
122 #include <linux/ctype.h>
123 #include <linux/if_arp.h>
124 #include <linux/if_vlan.h>
125 #include <linux/ip.h>
127 #include <net/mpls.h>
128 #include <linux/ipv6.h>
129 #include <linux/in.h>
130 #include <linux/jhash.h>
131 #include <linux/random.h>
132 #include <trace/events/napi.h>
133 #include <trace/events/net.h>
134 #include <trace/events/skb.h>
135 #include <linux/pci.h>
136 #include <linux/inetdevice.h>
137 #include <linux/cpu_rmap.h>
138 #include <linux/static_key.h>
139 #include <linux/hashtable.h>
140 #include <linux/vmalloc.h>
141 #include <linux/if_macvlan.h>
142 #include <linux/errqueue.h>
143 #include <linux/hrtimer.h>
144 #include <linux/netfilter_ingress.h>
145 #include <linux/crash_dump.h>
146 #include <linux/sctp.h>
147 #include <net/udp_tunnel.h>
148 #include <linux/net_namespace.h>
150 #include "net-sysfs.h"
152 #define MAX_GRO_SKBS 8
154 /* This should be increased if a protocol with a bigger head is added. */
155 #define GRO_MAX_HEAD (MAX_HEADER + 128)
157 static DEFINE_SPINLOCK(ptype_lock);
158 static DEFINE_SPINLOCK(offload_lock);
159 struct list_head ptype_base[PTYPE_HASH_SIZE] __read_mostly;
160 struct list_head ptype_all __read_mostly; /* Taps */
161 static struct list_head offload_base __read_mostly;
163 static int netif_rx_internal(struct sk_buff *skb);
164 static int call_netdevice_notifiers_info(unsigned long val,
165 struct netdev_notifier_info *info);
166 static struct napi_struct *napi_by_id(unsigned int napi_id);
169 * The @dev_base_head list is protected by @dev_base_lock and the rtnl
172 * Pure readers hold dev_base_lock for reading, or rcu_read_lock()
174 * Writers must hold the rtnl semaphore while they loop through the
175 * dev_base_head list, and hold dev_base_lock for writing when they do the
176 * actual updates. This allows pure readers to access the list even
177 * while a writer is preparing to update it.
179 * To put it another way, dev_base_lock is held for writing only to
180 * protect against pure readers; the rtnl semaphore provides the
181 * protection against other writers.
183 * See, for example usages, register_netdevice() and
184 * unregister_netdevice(), which must be called with the rtnl
187 DEFINE_RWLOCK(dev_base_lock);
188 EXPORT_SYMBOL(dev_base_lock);
190 static DEFINE_MUTEX(ifalias_mutex);
192 /* protects napi_hash addition/deletion and napi_gen_id */
193 static DEFINE_SPINLOCK(napi_hash_lock);
195 static unsigned int napi_gen_id = NR_CPUS;
196 static DEFINE_READ_MOSTLY_HASHTABLE(napi_hash, 8);
198 static seqcount_t devnet_rename_seq;
200 static inline void dev_base_seq_inc(struct net *net)
202 while (++net->dev_base_seq == 0)
206 static inline struct hlist_head *dev_name_hash(struct net *net, const char *name)
208 unsigned int hash = full_name_hash(net, name, strnlen(name, IFNAMSIZ));
210 return &net->dev_name_head[hash_32(hash, NETDEV_HASHBITS)];
213 static inline struct hlist_head *dev_index_hash(struct net *net, int ifindex)
215 return &net->dev_index_head[ifindex & (NETDEV_HASHENTRIES - 1)];
218 static inline void rps_lock(struct softnet_data *sd)
221 spin_lock(&sd->input_pkt_queue.lock);
225 static inline void rps_unlock(struct softnet_data *sd)
228 spin_unlock(&sd->input_pkt_queue.lock);
232 /* Device list insertion */
233 static void list_netdevice(struct net_device *dev)
235 struct net *net = dev_net(dev);
239 write_lock_bh(&dev_base_lock);
240 list_add_tail_rcu(&dev->dev_list, &net->dev_base_head);
241 hlist_add_head_rcu(&dev->name_hlist, dev_name_hash(net, dev->name));
242 hlist_add_head_rcu(&dev->index_hlist,
243 dev_index_hash(net, dev->ifindex));
244 write_unlock_bh(&dev_base_lock);
246 dev_base_seq_inc(net);
249 /* Device list removal
250 * caller must respect a RCU grace period before freeing/reusing dev
252 static void unlist_netdevice(struct net_device *dev)
256 /* Unlink dev from the device chain */
257 write_lock_bh(&dev_base_lock);
258 list_del_rcu(&dev->dev_list);
259 hlist_del_rcu(&dev->name_hlist);
260 hlist_del_rcu(&dev->index_hlist);
261 write_unlock_bh(&dev_base_lock);
263 dev_base_seq_inc(dev_net(dev));
270 static RAW_NOTIFIER_HEAD(netdev_chain);
273 * Device drivers call our routines to queue packets here. We empty the
274 * queue in the local softnet handler.
277 DEFINE_PER_CPU_ALIGNED(struct softnet_data, softnet_data);
278 EXPORT_PER_CPU_SYMBOL(softnet_data);
280 #ifdef CONFIG_LOCKDEP
282 * register_netdevice() inits txq->_xmit_lock and sets lockdep class
283 * according to dev->type
285 static const unsigned short netdev_lock_type[] = {
286 ARPHRD_NETROM, ARPHRD_ETHER, ARPHRD_EETHER, ARPHRD_AX25,
287 ARPHRD_PRONET, ARPHRD_CHAOS, ARPHRD_IEEE802, ARPHRD_ARCNET,
288 ARPHRD_APPLETLK, ARPHRD_DLCI, ARPHRD_ATM, ARPHRD_METRICOM,
289 ARPHRD_IEEE1394, ARPHRD_EUI64, ARPHRD_INFINIBAND, ARPHRD_SLIP,
290 ARPHRD_CSLIP, ARPHRD_SLIP6, ARPHRD_CSLIP6, ARPHRD_RSRVD,
291 ARPHRD_ADAPT, ARPHRD_ROSE, ARPHRD_X25, ARPHRD_HWX25,
292 ARPHRD_PPP, ARPHRD_CISCO, ARPHRD_LAPB, ARPHRD_DDCMP,
293 ARPHRD_RAWHDLC, ARPHRD_TUNNEL, ARPHRD_TUNNEL6, ARPHRD_FRAD,
294 ARPHRD_SKIP, ARPHRD_LOOPBACK, ARPHRD_LOCALTLK, ARPHRD_FDDI,
295 ARPHRD_BIF, ARPHRD_SIT, ARPHRD_IPDDP, ARPHRD_IPGRE,
296 ARPHRD_PIMREG, ARPHRD_HIPPI, ARPHRD_ASH, ARPHRD_ECONET,
297 ARPHRD_IRDA, ARPHRD_FCPP, ARPHRD_FCAL, ARPHRD_FCPL,
298 ARPHRD_FCFABRIC, ARPHRD_IEEE80211, ARPHRD_IEEE80211_PRISM,
299 ARPHRD_IEEE80211_RADIOTAP, ARPHRD_PHONET, ARPHRD_PHONET_PIPE,
300 ARPHRD_IEEE802154, ARPHRD_VOID, ARPHRD_NONE};
302 static const char *const netdev_lock_name[] = {
303 "_xmit_NETROM", "_xmit_ETHER", "_xmit_EETHER", "_xmit_AX25",
304 "_xmit_PRONET", "_xmit_CHAOS", "_xmit_IEEE802", "_xmit_ARCNET",
305 "_xmit_APPLETLK", "_xmit_DLCI", "_xmit_ATM", "_xmit_METRICOM",
306 "_xmit_IEEE1394", "_xmit_EUI64", "_xmit_INFINIBAND", "_xmit_SLIP",
307 "_xmit_CSLIP", "_xmit_SLIP6", "_xmit_CSLIP6", "_xmit_RSRVD",
308 "_xmit_ADAPT", "_xmit_ROSE", "_xmit_X25", "_xmit_HWX25",
309 "_xmit_PPP", "_xmit_CISCO", "_xmit_LAPB", "_xmit_DDCMP",
310 "_xmit_RAWHDLC", "_xmit_TUNNEL", "_xmit_TUNNEL6", "_xmit_FRAD",
311 "_xmit_SKIP", "_xmit_LOOPBACK", "_xmit_LOCALTLK", "_xmit_FDDI",
312 "_xmit_BIF", "_xmit_SIT", "_xmit_IPDDP", "_xmit_IPGRE",
313 "_xmit_PIMREG", "_xmit_HIPPI", "_xmit_ASH", "_xmit_ECONET",
314 "_xmit_IRDA", "_xmit_FCPP", "_xmit_FCAL", "_xmit_FCPL",
315 "_xmit_FCFABRIC", "_xmit_IEEE80211", "_xmit_IEEE80211_PRISM",
316 "_xmit_IEEE80211_RADIOTAP", "_xmit_PHONET", "_xmit_PHONET_PIPE",
317 "_xmit_IEEE802154", "_xmit_VOID", "_xmit_NONE"};
319 static struct lock_class_key netdev_xmit_lock_key[ARRAY_SIZE(netdev_lock_type)];
320 static struct lock_class_key netdev_addr_lock_key[ARRAY_SIZE(netdev_lock_type)];
322 static inline unsigned short netdev_lock_pos(unsigned short dev_type)
326 for (i = 0; i < ARRAY_SIZE(netdev_lock_type); i++)
327 if (netdev_lock_type[i] == dev_type)
329 /* the last key is used by default */
330 return ARRAY_SIZE(netdev_lock_type) - 1;
333 static inline void netdev_set_xmit_lockdep_class(spinlock_t *lock,
334 unsigned short dev_type)
338 i = netdev_lock_pos(dev_type);
339 lockdep_set_class_and_name(lock, &netdev_xmit_lock_key[i],
340 netdev_lock_name[i]);
343 static inline void netdev_set_addr_lockdep_class(struct net_device *dev)
347 i = netdev_lock_pos(dev->type);
348 lockdep_set_class_and_name(&dev->addr_list_lock,
349 &netdev_addr_lock_key[i],
350 netdev_lock_name[i]);
353 static inline void netdev_set_xmit_lockdep_class(spinlock_t *lock,
354 unsigned short dev_type)
357 static inline void netdev_set_addr_lockdep_class(struct net_device *dev)
362 /*******************************************************************************
364 * Protocol management and registration routines
366 *******************************************************************************/
370 * Add a protocol ID to the list. Now that the input handler is
371 * smarter we can dispense with all the messy stuff that used to be
374 * BEWARE!!! Protocol handlers, mangling input packets,
375 * MUST BE last in hash buckets and checking protocol handlers
376 * MUST start from promiscuous ptype_all chain in net_bh.
377 * It is true now, do not change it.
378 * Explanation follows: if protocol handler, mangling packet, will
379 * be the first on list, it is not able to sense, that packet
380 * is cloned and should be copied-on-write, so that it will
381 * change it and subsequent readers will get broken packet.
385 static inline struct list_head *ptype_head(const struct packet_type *pt)
387 if (pt->type == htons(ETH_P_ALL))
388 return pt->dev ? &pt->dev->ptype_all : &ptype_all;
390 return pt->dev ? &pt->dev->ptype_specific :
391 &ptype_base[ntohs(pt->type) & PTYPE_HASH_MASK];
395 * dev_add_pack - add packet handler
396 * @pt: packet type declaration
398 * Add a protocol handler to the networking stack. The passed &packet_type
399 * is linked into kernel lists and may not be freed until it has been
400 * removed from the kernel lists.
402 * This call does not sleep therefore it can not
403 * guarantee all CPU's that are in middle of receiving packets
404 * will see the new packet type (until the next received packet).
407 void dev_add_pack(struct packet_type *pt)
409 struct list_head *head = ptype_head(pt);
411 spin_lock(&ptype_lock);
412 list_add_rcu(&pt->list, head);
413 spin_unlock(&ptype_lock);
415 EXPORT_SYMBOL(dev_add_pack);
418 * __dev_remove_pack - remove packet handler
419 * @pt: packet type declaration
421 * Remove a protocol handler that was previously added to the kernel
422 * protocol handlers by dev_add_pack(). The passed &packet_type is removed
423 * from the kernel lists and can be freed or reused once this function
426 * The packet type might still be in use by receivers
427 * and must not be freed until after all the CPU's have gone
428 * through a quiescent state.
430 void __dev_remove_pack(struct packet_type *pt)
432 struct list_head *head = ptype_head(pt);
433 struct packet_type *pt1;
435 spin_lock(&ptype_lock);
437 list_for_each_entry(pt1, head, list) {
439 list_del_rcu(&pt->list);
444 pr_warn("dev_remove_pack: %p not found\n", pt);
446 spin_unlock(&ptype_lock);
448 EXPORT_SYMBOL(__dev_remove_pack);
451 * dev_remove_pack - remove packet handler
452 * @pt: packet type declaration
454 * Remove a protocol handler that was previously added to the kernel
455 * protocol handlers by dev_add_pack(). The passed &packet_type is removed
456 * from the kernel lists and can be freed or reused once this function
459 * This call sleeps to guarantee that no CPU is looking at the packet
462 void dev_remove_pack(struct packet_type *pt)
464 __dev_remove_pack(pt);
468 EXPORT_SYMBOL(dev_remove_pack);
472 * dev_add_offload - register offload handlers
473 * @po: protocol offload declaration
475 * Add protocol offload handlers to the networking stack. The passed
476 * &proto_offload is linked into kernel lists and may not be freed until
477 * it has been removed from the kernel lists.
479 * This call does not sleep therefore it can not
480 * guarantee all CPU's that are in middle of receiving packets
481 * will see the new offload handlers (until the next received packet).
483 void dev_add_offload(struct packet_offload *po)
485 struct packet_offload *elem;
487 spin_lock(&offload_lock);
488 list_for_each_entry(elem, &offload_base, list) {
489 if (po->priority < elem->priority)
492 list_add_rcu(&po->list, elem->list.prev);
493 spin_unlock(&offload_lock);
495 EXPORT_SYMBOL(dev_add_offload);
498 * __dev_remove_offload - remove offload handler
499 * @po: packet offload declaration
501 * Remove a protocol offload handler that was previously added to the
502 * kernel offload handlers by dev_add_offload(). The passed &offload_type
503 * is removed from the kernel lists and can be freed or reused once this
506 * The packet type might still be in use by receivers
507 * and must not be freed until after all the CPU's have gone
508 * through a quiescent state.
510 static void __dev_remove_offload(struct packet_offload *po)
512 struct list_head *head = &offload_base;
513 struct packet_offload *po1;
515 spin_lock(&offload_lock);
517 list_for_each_entry(po1, head, list) {
519 list_del_rcu(&po->list);
524 pr_warn("dev_remove_offload: %p not found\n", po);
526 spin_unlock(&offload_lock);
530 * dev_remove_offload - remove packet offload handler
531 * @po: packet offload declaration
533 * Remove a packet offload handler that was previously added to the kernel
534 * offload handlers by dev_add_offload(). The passed &offload_type is
535 * removed from the kernel lists and can be freed or reused once this
538 * This call sleeps to guarantee that no CPU is looking at the packet
541 void dev_remove_offload(struct packet_offload *po)
543 __dev_remove_offload(po);
547 EXPORT_SYMBOL(dev_remove_offload);
549 /******************************************************************************
551 * Device Boot-time Settings Routines
553 ******************************************************************************/
555 /* Boot time configuration table */
556 static struct netdev_boot_setup dev_boot_setup[NETDEV_BOOT_SETUP_MAX];
559 * netdev_boot_setup_add - add new setup entry
560 * @name: name of the device
561 * @map: configured settings for the device
563 * Adds new setup entry to the dev_boot_setup list. The function
564 * returns 0 on error and 1 on success. This is a generic routine to
567 static int netdev_boot_setup_add(char *name, struct ifmap *map)
569 struct netdev_boot_setup *s;
573 for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++) {
574 if (s[i].name[0] == '\0' || s[i].name[0] == ' ') {
575 memset(s[i].name, 0, sizeof(s[i].name));
576 strlcpy(s[i].name, name, IFNAMSIZ);
577 memcpy(&s[i].map, map, sizeof(s[i].map));
582 return i >= NETDEV_BOOT_SETUP_MAX ? 0 : 1;
586 * netdev_boot_setup_check - check boot time settings
587 * @dev: the netdevice
589 * Check boot time settings for the device.
590 * The found settings are set for the device to be used
591 * later in the device probing.
592 * Returns 0 if no settings found, 1 if they are.
594 int netdev_boot_setup_check(struct net_device *dev)
596 struct netdev_boot_setup *s = dev_boot_setup;
599 for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++) {
600 if (s[i].name[0] != '\0' && s[i].name[0] != ' ' &&
601 !strcmp(dev->name, s[i].name)) {
602 dev->irq = s[i].map.irq;
603 dev->base_addr = s[i].map.base_addr;
604 dev->mem_start = s[i].map.mem_start;
605 dev->mem_end = s[i].map.mem_end;
611 EXPORT_SYMBOL(netdev_boot_setup_check);
615 * netdev_boot_base - get address from boot time settings
616 * @prefix: prefix for network device
617 * @unit: id for network device
619 * Check boot time settings for the base address of device.
620 * The found settings are set for the device to be used
621 * later in the device probing.
622 * Returns 0 if no settings found.
624 unsigned long netdev_boot_base(const char *prefix, int unit)
626 const struct netdev_boot_setup *s = dev_boot_setup;
630 sprintf(name, "%s%d", prefix, unit);
633 * If device already registered then return base of 1
634 * to indicate not to probe for this interface
636 if (__dev_get_by_name(&init_net, name))
639 for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++)
640 if (!strcmp(name, s[i].name))
641 return s[i].map.base_addr;
646 * Saves at boot time configured settings for any netdevice.
648 int __init netdev_boot_setup(char *str)
653 str = get_options(str, ARRAY_SIZE(ints), ints);
658 memset(&map, 0, sizeof(map));
662 map.base_addr = ints[2];
664 map.mem_start = ints[3];
666 map.mem_end = ints[4];
668 /* Add new entry to the list */
669 return netdev_boot_setup_add(str, &map);
672 __setup("netdev=", netdev_boot_setup);
674 /*******************************************************************************
676 * Device Interface Subroutines
678 *******************************************************************************/
681 * dev_get_iflink - get 'iflink' value of a interface
682 * @dev: targeted interface
684 * Indicates the ifindex the interface is linked to.
685 * Physical interfaces have the same 'ifindex' and 'iflink' values.
688 int dev_get_iflink(const struct net_device *dev)
690 if (dev->netdev_ops && dev->netdev_ops->ndo_get_iflink)
691 return dev->netdev_ops->ndo_get_iflink(dev);
695 EXPORT_SYMBOL(dev_get_iflink);
698 * dev_fill_metadata_dst - Retrieve tunnel egress information.
699 * @dev: targeted interface
702 * For better visibility of tunnel traffic OVS needs to retrieve
703 * egress tunnel information for a packet. Following API allows
704 * user to get this info.
706 int dev_fill_metadata_dst(struct net_device *dev, struct sk_buff *skb)
708 struct ip_tunnel_info *info;
710 if (!dev->netdev_ops || !dev->netdev_ops->ndo_fill_metadata_dst)
713 info = skb_tunnel_info_unclone(skb);
716 if (unlikely(!(info->mode & IP_TUNNEL_INFO_TX)))
719 return dev->netdev_ops->ndo_fill_metadata_dst(dev, skb);
721 EXPORT_SYMBOL_GPL(dev_fill_metadata_dst);
724 * __dev_get_by_name - find a device by its name
725 * @net: the applicable net namespace
726 * @name: name to find
728 * Find an interface by name. Must be called under RTNL semaphore
729 * or @dev_base_lock. If the name is found a pointer to the device
730 * is returned. If the name is not found then %NULL is returned. The
731 * reference counters are not incremented so the caller must be
732 * careful with locks.
735 struct net_device *__dev_get_by_name(struct net *net, const char *name)
737 struct net_device *dev;
738 struct hlist_head *head = dev_name_hash(net, name);
740 hlist_for_each_entry(dev, head, name_hlist)
741 if (!strncmp(dev->name, name, IFNAMSIZ))
746 EXPORT_SYMBOL(__dev_get_by_name);
749 * dev_get_by_name_rcu - find a device by its name
750 * @net: the applicable net namespace
751 * @name: name to find
753 * Find an interface by name.
754 * If the name is found a pointer to the device is returned.
755 * If the name is not found then %NULL is returned.
756 * The reference counters are not incremented so the caller must be
757 * careful with locks. The caller must hold RCU lock.
760 struct net_device *dev_get_by_name_rcu(struct net *net, const char *name)
762 struct net_device *dev;
763 struct hlist_head *head = dev_name_hash(net, name);
765 hlist_for_each_entry_rcu(dev, head, name_hlist)
766 if (!strncmp(dev->name, name, IFNAMSIZ))
771 EXPORT_SYMBOL(dev_get_by_name_rcu);
774 * dev_get_by_name - find a device by its name
775 * @net: the applicable net namespace
776 * @name: name to find
778 * Find an interface by name. This can be called from any
779 * context and does its own locking. The returned handle has
780 * the usage count incremented and the caller must use dev_put() to
781 * release it when it is no longer needed. %NULL is returned if no
782 * matching device is found.
785 struct net_device *dev_get_by_name(struct net *net, const char *name)
787 struct net_device *dev;
790 dev = dev_get_by_name_rcu(net, name);
796 EXPORT_SYMBOL(dev_get_by_name);
799 * __dev_get_by_index - find a device by its ifindex
800 * @net: the applicable net namespace
801 * @ifindex: index of device
803 * Search for an interface by index. Returns %NULL if the device
804 * is not found or a pointer to the device. The device has not
805 * had its reference counter increased so the caller must be careful
806 * about locking. The caller must hold either the RTNL semaphore
810 struct net_device *__dev_get_by_index(struct net *net, int ifindex)
812 struct net_device *dev;
813 struct hlist_head *head = dev_index_hash(net, ifindex);
815 hlist_for_each_entry(dev, head, index_hlist)
816 if (dev->ifindex == ifindex)
821 EXPORT_SYMBOL(__dev_get_by_index);
824 * dev_get_by_index_rcu - find a device by its ifindex
825 * @net: the applicable net namespace
826 * @ifindex: index of device
828 * Search for an interface by index. Returns %NULL if the device
829 * is not found or a pointer to the device. The device has not
830 * had its reference counter increased so the caller must be careful
831 * about locking. The caller must hold RCU lock.
834 struct net_device *dev_get_by_index_rcu(struct net *net, int ifindex)
836 struct net_device *dev;
837 struct hlist_head *head = dev_index_hash(net, ifindex);
839 hlist_for_each_entry_rcu(dev, head, index_hlist)
840 if (dev->ifindex == ifindex)
845 EXPORT_SYMBOL(dev_get_by_index_rcu);
849 * dev_get_by_index - find a device by its ifindex
850 * @net: the applicable net namespace
851 * @ifindex: index of device
853 * Search for an interface by index. Returns NULL if the device
854 * is not found or a pointer to the device. The device returned has
855 * had a reference added and the pointer is safe until the user calls
856 * dev_put to indicate they have finished with it.
859 struct net_device *dev_get_by_index(struct net *net, int ifindex)
861 struct net_device *dev;
864 dev = dev_get_by_index_rcu(net, ifindex);
870 EXPORT_SYMBOL(dev_get_by_index);
873 * dev_get_by_napi_id - find a device by napi_id
874 * @napi_id: ID of the NAPI struct
876 * Search for an interface by NAPI ID. Returns %NULL if the device
877 * is not found or a pointer to the device. The device has not had
878 * its reference counter increased so the caller must be careful
879 * about locking. The caller must hold RCU lock.
882 struct net_device *dev_get_by_napi_id(unsigned int napi_id)
884 struct napi_struct *napi;
886 WARN_ON_ONCE(!rcu_read_lock_held());
888 if (napi_id < MIN_NAPI_ID)
891 napi = napi_by_id(napi_id);
893 return napi ? napi->dev : NULL;
895 EXPORT_SYMBOL(dev_get_by_napi_id);
898 * netdev_get_name - get a netdevice name, knowing its ifindex.
899 * @net: network namespace
900 * @name: a pointer to the buffer where the name will be stored.
901 * @ifindex: the ifindex of the interface to get the name from.
903 * The use of raw_seqcount_begin() and cond_resched() before
904 * retrying is required as we want to give the writers a chance
905 * to complete when CONFIG_PREEMPT is not set.
907 int netdev_get_name(struct net *net, char *name, int ifindex)
909 struct net_device *dev;
913 seq = raw_seqcount_begin(&devnet_rename_seq);
915 dev = dev_get_by_index_rcu(net, ifindex);
921 strcpy(name, dev->name);
923 if (read_seqcount_retry(&devnet_rename_seq, seq)) {
932 * dev_getbyhwaddr_rcu - find a device by its hardware address
933 * @net: the applicable net namespace
934 * @type: media type of device
935 * @ha: hardware address
937 * Search for an interface by MAC address. Returns NULL if the device
938 * is not found or a pointer to the device.
939 * The caller must hold RCU or RTNL.
940 * The returned device has not had its ref count increased
941 * and the caller must therefore be careful about locking
945 struct net_device *dev_getbyhwaddr_rcu(struct net *net, unsigned short type,
948 struct net_device *dev;
950 for_each_netdev_rcu(net, dev)
951 if (dev->type == type &&
952 !memcmp(dev->dev_addr, ha, dev->addr_len))
957 EXPORT_SYMBOL(dev_getbyhwaddr_rcu);
959 struct net_device *__dev_getfirstbyhwtype(struct net *net, unsigned short type)
961 struct net_device *dev;
964 for_each_netdev(net, dev)
965 if (dev->type == type)
970 EXPORT_SYMBOL(__dev_getfirstbyhwtype);
972 struct net_device *dev_getfirstbyhwtype(struct net *net, unsigned short type)
974 struct net_device *dev, *ret = NULL;
977 for_each_netdev_rcu(net, dev)
978 if (dev->type == type) {
986 EXPORT_SYMBOL(dev_getfirstbyhwtype);
989 * __dev_get_by_flags - find any device with given flags
990 * @net: the applicable net namespace
991 * @if_flags: IFF_* values
992 * @mask: bitmask of bits in if_flags to check
994 * Search for any interface with the given flags. Returns NULL if a device
995 * is not found or a pointer to the device. Must be called inside
996 * rtnl_lock(), and result refcount is unchanged.
999 struct net_device *__dev_get_by_flags(struct net *net, unsigned short if_flags,
1000 unsigned short mask)
1002 struct net_device *dev, *ret;
1007 for_each_netdev(net, dev) {
1008 if (((dev->flags ^ if_flags) & mask) == 0) {
1015 EXPORT_SYMBOL(__dev_get_by_flags);
1018 * dev_valid_name - check if name is okay for network device
1019 * @name: name string
1021 * Network device names need to be valid file names to
1022 * to allow sysfs to work. We also disallow any kind of
1025 bool dev_valid_name(const char *name)
1029 if (strnlen(name, IFNAMSIZ) == IFNAMSIZ)
1031 if (!strcmp(name, ".") || !strcmp(name, ".."))
1035 if (*name == '/' || *name == ':' || isspace(*name))
1041 EXPORT_SYMBOL(dev_valid_name);
1044 * __dev_alloc_name - allocate a name for a device
1045 * @net: network namespace to allocate the device name in
1046 * @name: name format string
1047 * @buf: scratch buffer and result name string
1049 * Passed a format string - eg "lt%d" it will try and find a suitable
1050 * id. It scans list of devices to build up a free map, then chooses
1051 * the first empty slot. The caller must hold the dev_base or rtnl lock
1052 * while allocating the name and adding the device in order to avoid
1054 * Limited to bits_per_byte * page size devices (ie 32K on most platforms).
1055 * Returns the number of the unit assigned or a negative errno code.
1058 static int __dev_alloc_name(struct net *net, const char *name, char *buf)
1062 const int max_netdevices = 8*PAGE_SIZE;
1063 unsigned long *inuse;
1064 struct net_device *d;
1066 if (!dev_valid_name(name))
1069 p = strchr(name, '%');
1072 * Verify the string as this thing may have come from
1073 * the user. There must be either one "%d" and no other "%"
1076 if (p[1] != 'd' || strchr(p + 2, '%'))
1079 /* Use one page as a bit array of possible slots */
1080 inuse = (unsigned long *) get_zeroed_page(GFP_ATOMIC);
1084 for_each_netdev(net, d) {
1085 if (!sscanf(d->name, name, &i))
1087 if (i < 0 || i >= max_netdevices)
1090 /* avoid cases where sscanf is not exact inverse of printf */
1091 snprintf(buf, IFNAMSIZ, name, i);
1092 if (!strncmp(buf, d->name, IFNAMSIZ))
1096 i = find_first_zero_bit(inuse, max_netdevices);
1097 free_page((unsigned long) inuse);
1100 snprintf(buf, IFNAMSIZ, name, i);
1101 if (!__dev_get_by_name(net, buf))
1104 /* It is possible to run out of possible slots
1105 * when the name is long and there isn't enough space left
1106 * for the digits, or if all bits are used.
1111 static int dev_alloc_name_ns(struct net *net,
1112 struct net_device *dev,
1119 ret = __dev_alloc_name(net, name, buf);
1121 strlcpy(dev->name, buf, IFNAMSIZ);
1126 * dev_alloc_name - allocate a name for a device
1128 * @name: name format string
1130 * Passed a format string - eg "lt%d" it will try and find a suitable
1131 * id. It scans list of devices to build up a free map, then chooses
1132 * the first empty slot. The caller must hold the dev_base or rtnl lock
1133 * while allocating the name and adding the device in order to avoid
1135 * Limited to bits_per_byte * page size devices (ie 32K on most platforms).
1136 * Returns the number of the unit assigned or a negative errno code.
1139 int dev_alloc_name(struct net_device *dev, const char *name)
1141 return dev_alloc_name_ns(dev_net(dev), dev, name);
1143 EXPORT_SYMBOL(dev_alloc_name);
1145 int dev_get_valid_name(struct net *net, struct net_device *dev,
1150 if (!dev_valid_name(name))
1153 if (strchr(name, '%'))
1154 return dev_alloc_name_ns(net, dev, name);
1155 else if (__dev_get_by_name(net, name))
1157 else if (dev->name != name)
1158 strlcpy(dev->name, name, IFNAMSIZ);
1162 EXPORT_SYMBOL(dev_get_valid_name);
1165 * dev_change_name - change name of a device
1167 * @newname: name (or format string) must be at least IFNAMSIZ
1169 * Change name of a device, can pass format strings "eth%d".
1172 int dev_change_name(struct net_device *dev, const char *newname)
1174 unsigned char old_assign_type;
1175 char oldname[IFNAMSIZ];
1181 BUG_ON(!dev_net(dev));
1184 if (dev->flags & IFF_UP)
1187 write_seqcount_begin(&devnet_rename_seq);
1189 if (strncmp(newname, dev->name, IFNAMSIZ) == 0) {
1190 write_seqcount_end(&devnet_rename_seq);
1194 memcpy(oldname, dev->name, IFNAMSIZ);
1196 err = dev_get_valid_name(net, dev, newname);
1198 write_seqcount_end(&devnet_rename_seq);
1202 if (oldname[0] && !strchr(oldname, '%'))
1203 netdev_info(dev, "renamed from %s\n", oldname);
1205 old_assign_type = dev->name_assign_type;
1206 dev->name_assign_type = NET_NAME_RENAMED;
1209 ret = device_rename(&dev->dev, dev->name);
1211 memcpy(dev->name, oldname, IFNAMSIZ);
1212 dev->name_assign_type = old_assign_type;
1213 write_seqcount_end(&devnet_rename_seq);
1217 write_seqcount_end(&devnet_rename_seq);
1219 netdev_adjacent_rename_links(dev, oldname);
1221 write_lock_bh(&dev_base_lock);
1222 hlist_del_rcu(&dev->name_hlist);
1223 write_unlock_bh(&dev_base_lock);
1227 write_lock_bh(&dev_base_lock);
1228 hlist_add_head_rcu(&dev->name_hlist, dev_name_hash(net, dev->name));
1229 write_unlock_bh(&dev_base_lock);
1231 ret = call_netdevice_notifiers(NETDEV_CHANGENAME, dev);
1232 ret = notifier_to_errno(ret);
1235 /* err >= 0 after dev_alloc_name() or stores the first errno */
1238 write_seqcount_begin(&devnet_rename_seq);
1239 memcpy(dev->name, oldname, IFNAMSIZ);
1240 memcpy(oldname, newname, IFNAMSIZ);
1241 dev->name_assign_type = old_assign_type;
1242 old_assign_type = NET_NAME_RENAMED;
1245 pr_err("%s: name change rollback failed: %d\n",
1254 * dev_set_alias - change ifalias of a device
1256 * @alias: name up to IFALIASZ
1257 * @len: limit of bytes to copy from info
1259 * Set ifalias for a device,
1261 int dev_set_alias(struct net_device *dev, const char *alias, size_t len)
1263 struct dev_ifalias *new_alias = NULL;
1265 if (len >= IFALIASZ)
1269 new_alias = kmalloc(sizeof(*new_alias) + len + 1, GFP_KERNEL);
1273 memcpy(new_alias->ifalias, alias, len);
1274 new_alias->ifalias[len] = 0;
1277 mutex_lock(&ifalias_mutex);
1278 rcu_swap_protected(dev->ifalias, new_alias,
1279 mutex_is_locked(&ifalias_mutex));
1280 mutex_unlock(&ifalias_mutex);
1283 kfree_rcu(new_alias, rcuhead);
1287 EXPORT_SYMBOL(dev_set_alias);
1290 * dev_get_alias - get ifalias of a device
1292 * @name: buffer to store name of ifalias
1293 * @len: size of buffer
1295 * get ifalias for a device. Caller must make sure dev cannot go
1296 * away, e.g. rcu read lock or own a reference count to device.
1298 int dev_get_alias(const struct net_device *dev, char *name, size_t len)
1300 const struct dev_ifalias *alias;
1304 alias = rcu_dereference(dev->ifalias);
1306 ret = snprintf(name, len, "%s", alias->ifalias);
1313 * netdev_features_change - device changes features
1314 * @dev: device to cause notification
1316 * Called to indicate a device has changed features.
1318 void netdev_features_change(struct net_device *dev)
1320 call_netdevice_notifiers(NETDEV_FEAT_CHANGE, dev);
1322 EXPORT_SYMBOL(netdev_features_change);
1325 * netdev_state_change - device changes state
1326 * @dev: device to cause notification
1328 * Called to indicate a device has changed state. This function calls
1329 * the notifier chains for netdev_chain and sends a NEWLINK message
1330 * to the routing socket.
1332 void netdev_state_change(struct net_device *dev)
1334 if (dev->flags & IFF_UP) {
1335 struct netdev_notifier_change_info change_info = {
1339 call_netdevice_notifiers_info(NETDEV_CHANGE,
1341 rtmsg_ifinfo(RTM_NEWLINK, dev, 0, GFP_KERNEL);
1344 EXPORT_SYMBOL(netdev_state_change);
1347 * netdev_notify_peers - notify network peers about existence of @dev
1348 * @dev: network device
1350 * Generate traffic such that interested network peers are aware of
1351 * @dev, such as by generating a gratuitous ARP. This may be used when
1352 * a device wants to inform the rest of the network about some sort of
1353 * reconfiguration such as a failover event or virtual machine
1356 void netdev_notify_peers(struct net_device *dev)
1359 call_netdevice_notifiers(NETDEV_NOTIFY_PEERS, dev);
1360 call_netdevice_notifiers(NETDEV_RESEND_IGMP, dev);
1363 EXPORT_SYMBOL(netdev_notify_peers);
1365 static int __dev_open(struct net_device *dev)
1367 const struct net_device_ops *ops = dev->netdev_ops;
1372 if (!netif_device_present(dev))
1375 /* Block netpoll from trying to do any rx path servicing.
1376 * If we don't do this there is a chance ndo_poll_controller
1377 * or ndo_poll may be running while we open the device
1379 netpoll_poll_disable(dev);
1381 ret = call_netdevice_notifiers(NETDEV_PRE_UP, dev);
1382 ret = notifier_to_errno(ret);
1386 set_bit(__LINK_STATE_START, &dev->state);
1388 if (ops->ndo_validate_addr)
1389 ret = ops->ndo_validate_addr(dev);
1391 if (!ret && ops->ndo_open)
1392 ret = ops->ndo_open(dev);
1394 netpoll_poll_enable(dev);
1397 clear_bit(__LINK_STATE_START, &dev->state);
1399 dev->flags |= IFF_UP;
1400 dev_set_rx_mode(dev);
1402 add_device_randomness(dev->dev_addr, dev->addr_len);
1409 * dev_open - prepare an interface for use.
1410 * @dev: device to open
1412 * Takes a device from down to up state. The device's private open
1413 * function is invoked and then the multicast lists are loaded. Finally
1414 * the device is moved into the up state and a %NETDEV_UP message is
1415 * sent to the netdev notifier chain.
1417 * Calling this function on an active interface is a nop. On a failure
1418 * a negative errno code is returned.
1420 int dev_open(struct net_device *dev)
1424 if (dev->flags & IFF_UP)
1427 ret = __dev_open(dev);
1431 rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP|IFF_RUNNING, GFP_KERNEL);
1432 call_netdevice_notifiers(NETDEV_UP, dev);
1436 EXPORT_SYMBOL(dev_open);
1438 static void __dev_close_many(struct list_head *head)
1440 struct net_device *dev;
1445 list_for_each_entry(dev, head, close_list) {
1446 /* Temporarily disable netpoll until the interface is down */
1447 netpoll_poll_disable(dev);
1449 call_netdevice_notifiers(NETDEV_GOING_DOWN, dev);
1451 clear_bit(__LINK_STATE_START, &dev->state);
1453 /* Synchronize to scheduled poll. We cannot touch poll list, it
1454 * can be even on different cpu. So just clear netif_running().
1456 * dev->stop() will invoke napi_disable() on all of it's
1457 * napi_struct instances on this device.
1459 smp_mb__after_atomic(); /* Commit netif_running(). */
1462 dev_deactivate_many(head);
1464 list_for_each_entry(dev, head, close_list) {
1465 const struct net_device_ops *ops = dev->netdev_ops;
1468 * Call the device specific close. This cannot fail.
1469 * Only if device is UP
1471 * We allow it to be called even after a DETACH hot-plug
1477 dev->flags &= ~IFF_UP;
1478 netpoll_poll_enable(dev);
1482 static void __dev_close(struct net_device *dev)
1486 list_add(&dev->close_list, &single);
1487 __dev_close_many(&single);
1491 void dev_close_many(struct list_head *head, bool unlink)
1493 struct net_device *dev, *tmp;
1495 /* Remove the devices that don't need to be closed */
1496 list_for_each_entry_safe(dev, tmp, head, close_list)
1497 if (!(dev->flags & IFF_UP))
1498 list_del_init(&dev->close_list);
1500 __dev_close_many(head);
1502 list_for_each_entry_safe(dev, tmp, head, close_list) {
1503 rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP|IFF_RUNNING, GFP_KERNEL);
1504 call_netdevice_notifiers(NETDEV_DOWN, dev);
1506 list_del_init(&dev->close_list);
1509 EXPORT_SYMBOL(dev_close_many);
1512 * dev_close - shutdown an interface.
1513 * @dev: device to shutdown
1515 * This function moves an active device into down state. A
1516 * %NETDEV_GOING_DOWN is sent to the netdev notifier chain. The device
1517 * is then deactivated and finally a %NETDEV_DOWN is sent to the notifier
1520 void dev_close(struct net_device *dev)
1522 if (dev->flags & IFF_UP) {
1525 list_add(&dev->close_list, &single);
1526 dev_close_many(&single, true);
1530 EXPORT_SYMBOL(dev_close);
1534 * dev_disable_lro - disable Large Receive Offload on a device
1537 * Disable Large Receive Offload (LRO) on a net device. Must be
1538 * called under RTNL. This is needed if received packets may be
1539 * forwarded to another interface.
1541 void dev_disable_lro(struct net_device *dev)
1543 struct net_device *lower_dev;
1544 struct list_head *iter;
1546 dev->wanted_features &= ~NETIF_F_LRO;
1547 netdev_update_features(dev);
1549 if (unlikely(dev->features & NETIF_F_LRO))
1550 netdev_WARN(dev, "failed to disable LRO!\n");
1552 netdev_for_each_lower_dev(dev, lower_dev, iter)
1553 dev_disable_lro(lower_dev);
1555 EXPORT_SYMBOL(dev_disable_lro);
1558 * dev_disable_gro_hw - disable HW Generic Receive Offload on a device
1561 * Disable HW Generic Receive Offload (GRO_HW) on a net device. Must be
1562 * called under RTNL. This is needed if Generic XDP is installed on
1565 static void dev_disable_gro_hw(struct net_device *dev)
1567 dev->wanted_features &= ~NETIF_F_GRO_HW;
1568 netdev_update_features(dev);
1570 if (unlikely(dev->features & NETIF_F_GRO_HW))
1571 netdev_WARN(dev, "failed to disable GRO_HW!\n");
1574 const char *netdev_cmd_to_name(enum netdev_cmd cmd)
1577 case NETDEV_##val: \
1578 return "NETDEV_" __stringify(val);
1580 N(UP) N(DOWN) N(REBOOT) N(CHANGE) N(REGISTER) N(UNREGISTER)
1581 N(CHANGEMTU) N(CHANGEADDR) N(GOING_DOWN) N(CHANGENAME) N(FEAT_CHANGE)
1582 N(BONDING_FAILOVER) N(PRE_UP) N(PRE_TYPE_CHANGE) N(POST_TYPE_CHANGE)
1583 N(POST_INIT) N(RELEASE) N(NOTIFY_PEERS) N(JOIN) N(CHANGEUPPER)
1584 N(RESEND_IGMP) N(PRECHANGEMTU) N(CHANGEINFODATA) N(BONDING_INFO)
1585 N(PRECHANGEUPPER) N(CHANGELOWERSTATE) N(UDP_TUNNEL_PUSH_INFO)
1586 N(UDP_TUNNEL_DROP_INFO) N(CHANGE_TX_QUEUE_LEN)
1587 N(CVLAN_FILTER_PUSH_INFO) N(CVLAN_FILTER_DROP_INFO)
1588 N(SVLAN_FILTER_PUSH_INFO) N(SVLAN_FILTER_DROP_INFO)
1591 return "UNKNOWN_NETDEV_EVENT";
1593 EXPORT_SYMBOL_GPL(netdev_cmd_to_name);
1595 static int call_netdevice_notifier(struct notifier_block *nb, unsigned long val,
1596 struct net_device *dev)
1598 struct netdev_notifier_info info = {
1602 return nb->notifier_call(nb, val, &info);
1605 static int dev_boot_phase = 1;
1608 * register_netdevice_notifier - register a network notifier block
1611 * Register a notifier to be called when network device events occur.
1612 * The notifier passed is linked into the kernel structures and must
1613 * not be reused until it has been unregistered. A negative errno code
1614 * is returned on a failure.
1616 * When registered all registration and up events are replayed
1617 * to the new notifier to allow device to have a race free
1618 * view of the network device list.
1621 int register_netdevice_notifier(struct notifier_block *nb)
1623 struct net_device *dev;
1624 struct net_device *last;
1628 /* Close race with setup_net() and cleanup_net() */
1629 down_write(&pernet_ops_rwsem);
1631 err = raw_notifier_chain_register(&netdev_chain, nb);
1637 for_each_netdev(net, dev) {
1638 err = call_netdevice_notifier(nb, NETDEV_REGISTER, dev);
1639 err = notifier_to_errno(err);
1643 if (!(dev->flags & IFF_UP))
1646 call_netdevice_notifier(nb, NETDEV_UP, dev);
1652 up_write(&pernet_ops_rwsem);
1658 for_each_netdev(net, dev) {
1662 if (dev->flags & IFF_UP) {
1663 call_netdevice_notifier(nb, NETDEV_GOING_DOWN,
1665 call_netdevice_notifier(nb, NETDEV_DOWN, dev);
1667 call_netdevice_notifier(nb, NETDEV_UNREGISTER, dev);
1672 raw_notifier_chain_unregister(&netdev_chain, nb);
1675 EXPORT_SYMBOL(register_netdevice_notifier);
1678 * unregister_netdevice_notifier - unregister a network notifier block
1681 * Unregister a notifier previously registered by
1682 * register_netdevice_notifier(). The notifier is unlinked into the
1683 * kernel structures and may then be reused. A negative errno code
1684 * is returned on a failure.
1686 * After unregistering unregister and down device events are synthesized
1687 * for all devices on the device list to the removed notifier to remove
1688 * the need for special case cleanup code.
1691 int unregister_netdevice_notifier(struct notifier_block *nb)
1693 struct net_device *dev;
1697 /* Close race with setup_net() and cleanup_net() */
1698 down_write(&pernet_ops_rwsem);
1700 err = raw_notifier_chain_unregister(&netdev_chain, nb);
1705 for_each_netdev(net, dev) {
1706 if (dev->flags & IFF_UP) {
1707 call_netdevice_notifier(nb, NETDEV_GOING_DOWN,
1709 call_netdevice_notifier(nb, NETDEV_DOWN, dev);
1711 call_netdevice_notifier(nb, NETDEV_UNREGISTER, dev);
1716 up_write(&pernet_ops_rwsem);
1719 EXPORT_SYMBOL(unregister_netdevice_notifier);
1722 * call_netdevice_notifiers_info - call all network notifier blocks
1723 * @val: value passed unmodified to notifier function
1724 * @info: notifier information data
1726 * Call all network notifier blocks. Parameters and return value
1727 * are as for raw_notifier_call_chain().
1730 static int call_netdevice_notifiers_info(unsigned long val,
1731 struct netdev_notifier_info *info)
1734 return raw_notifier_call_chain(&netdev_chain, val, info);
1738 * call_netdevice_notifiers - call all network notifier blocks
1739 * @val: value passed unmodified to notifier function
1740 * @dev: net_device pointer passed unmodified to notifier function
1742 * Call all network notifier blocks. Parameters and return value
1743 * are as for raw_notifier_call_chain().
1746 int call_netdevice_notifiers(unsigned long val, struct net_device *dev)
1748 struct netdev_notifier_info info = {
1752 return call_netdevice_notifiers_info(val, &info);
1754 EXPORT_SYMBOL(call_netdevice_notifiers);
1756 #ifdef CONFIG_NET_INGRESS
1757 static DEFINE_STATIC_KEY_FALSE(ingress_needed_key);
1759 void net_inc_ingress_queue(void)
1761 static_branch_inc(&ingress_needed_key);
1763 EXPORT_SYMBOL_GPL(net_inc_ingress_queue);
1765 void net_dec_ingress_queue(void)
1767 static_branch_dec(&ingress_needed_key);
1769 EXPORT_SYMBOL_GPL(net_dec_ingress_queue);
1772 #ifdef CONFIG_NET_EGRESS
1773 static DEFINE_STATIC_KEY_FALSE(egress_needed_key);
1775 void net_inc_egress_queue(void)
1777 static_branch_inc(&egress_needed_key);
1779 EXPORT_SYMBOL_GPL(net_inc_egress_queue);
1781 void net_dec_egress_queue(void)
1783 static_branch_dec(&egress_needed_key);
1785 EXPORT_SYMBOL_GPL(net_dec_egress_queue);
1788 static DEFINE_STATIC_KEY_FALSE(netstamp_needed_key);
1789 #ifdef HAVE_JUMP_LABEL
1790 static atomic_t netstamp_needed_deferred;
1791 static atomic_t netstamp_wanted;
1792 static void netstamp_clear(struct work_struct *work)
1794 int deferred = atomic_xchg(&netstamp_needed_deferred, 0);
1797 wanted = atomic_add_return(deferred, &netstamp_wanted);
1799 static_branch_enable(&netstamp_needed_key);
1801 static_branch_disable(&netstamp_needed_key);
1803 static DECLARE_WORK(netstamp_work, netstamp_clear);
1806 void net_enable_timestamp(void)
1808 #ifdef HAVE_JUMP_LABEL
1812 wanted = atomic_read(&netstamp_wanted);
1815 if (atomic_cmpxchg(&netstamp_wanted, wanted, wanted + 1) == wanted)
1818 atomic_inc(&netstamp_needed_deferred);
1819 schedule_work(&netstamp_work);
1821 static_branch_inc(&netstamp_needed_key);
1824 EXPORT_SYMBOL(net_enable_timestamp);
1826 void net_disable_timestamp(void)
1828 #ifdef HAVE_JUMP_LABEL
1832 wanted = atomic_read(&netstamp_wanted);
1835 if (atomic_cmpxchg(&netstamp_wanted, wanted, wanted - 1) == wanted)
1838 atomic_dec(&netstamp_needed_deferred);
1839 schedule_work(&netstamp_work);
1841 static_branch_dec(&netstamp_needed_key);
1844 EXPORT_SYMBOL(net_disable_timestamp);
1846 static inline void net_timestamp_set(struct sk_buff *skb)
1849 if (static_branch_unlikely(&netstamp_needed_key))
1850 __net_timestamp(skb);
1853 #define net_timestamp_check(COND, SKB) \
1854 if (static_branch_unlikely(&netstamp_needed_key)) { \
1855 if ((COND) && !(SKB)->tstamp) \
1856 __net_timestamp(SKB); \
1859 bool is_skb_forwardable(const struct net_device *dev, const struct sk_buff *skb)
1863 if (!(dev->flags & IFF_UP))
1866 len = dev->mtu + dev->hard_header_len + VLAN_HLEN;
1867 if (skb->len <= len)
1870 /* if TSO is enabled, we don't care about the length as the packet
1871 * could be forwarded without being segmented before
1873 if (skb_is_gso(skb))
1878 EXPORT_SYMBOL_GPL(is_skb_forwardable);
1880 int __dev_forward_skb(struct net_device *dev, struct sk_buff *skb)
1882 int ret = ____dev_forward_skb(dev, skb);
1885 skb->protocol = eth_type_trans(skb, dev);
1886 skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN);
1891 EXPORT_SYMBOL_GPL(__dev_forward_skb);
1894 * dev_forward_skb - loopback an skb to another netif
1896 * @dev: destination network device
1897 * @skb: buffer to forward
1900 * NET_RX_SUCCESS (no congestion)
1901 * NET_RX_DROP (packet was dropped, but freed)
1903 * dev_forward_skb can be used for injecting an skb from the
1904 * start_xmit function of one device into the receive queue
1905 * of another device.
1907 * The receiving device may be in another namespace, so
1908 * we have to clear all information in the skb that could
1909 * impact namespace isolation.
1911 int dev_forward_skb(struct net_device *dev, struct sk_buff *skb)
1913 return __dev_forward_skb(dev, skb) ?: netif_rx_internal(skb);
1915 EXPORT_SYMBOL_GPL(dev_forward_skb);
1917 static inline int deliver_skb(struct sk_buff *skb,
1918 struct packet_type *pt_prev,
1919 struct net_device *orig_dev)
1921 if (unlikely(skb_orphan_frags_rx(skb, GFP_ATOMIC)))
1923 refcount_inc(&skb->users);
1924 return pt_prev->func(skb, skb->dev, pt_prev, orig_dev);
1927 static inline void deliver_ptype_list_skb(struct sk_buff *skb,
1928 struct packet_type **pt,
1929 struct net_device *orig_dev,
1931 struct list_head *ptype_list)
1933 struct packet_type *ptype, *pt_prev = *pt;
1935 list_for_each_entry_rcu(ptype, ptype_list, list) {
1936 if (ptype->type != type)
1939 deliver_skb(skb, pt_prev, orig_dev);
1945 static inline bool skb_loop_sk(struct packet_type *ptype, struct sk_buff *skb)
1947 if (!ptype->af_packet_priv || !skb->sk)
1950 if (ptype->id_match)
1951 return ptype->id_match(ptype, skb->sk);
1952 else if ((struct sock *)ptype->af_packet_priv == skb->sk)
1959 * Support routine. Sends outgoing frames to any network
1960 * taps currently in use.
1963 void dev_queue_xmit_nit(struct sk_buff *skb, struct net_device *dev)
1965 struct packet_type *ptype;
1966 struct sk_buff *skb2 = NULL;
1967 struct packet_type *pt_prev = NULL;
1968 struct list_head *ptype_list = &ptype_all;
1972 list_for_each_entry_rcu(ptype, ptype_list, list) {
1973 /* Never send packets back to the socket
1974 * they originated from - MvS (miquels@drinkel.ow.org)
1976 if (skb_loop_sk(ptype, skb))
1980 deliver_skb(skb2, pt_prev, skb->dev);
1985 /* need to clone skb, done only once */
1986 skb2 = skb_clone(skb, GFP_ATOMIC);
1990 net_timestamp_set(skb2);
1992 /* skb->nh should be correctly
1993 * set by sender, so that the second statement is
1994 * just protection against buggy protocols.
1996 skb_reset_mac_header(skb2);
1998 if (skb_network_header(skb2) < skb2->data ||
1999 skb_network_header(skb2) > skb_tail_pointer(skb2)) {
2000 net_crit_ratelimited("protocol %04x is buggy, dev %s\n",
2001 ntohs(skb2->protocol),
2003 skb_reset_network_header(skb2);
2006 skb2->transport_header = skb2->network_header;
2007 skb2->pkt_type = PACKET_OUTGOING;
2011 if (ptype_list == &ptype_all) {
2012 ptype_list = &dev->ptype_all;
2017 if (!skb_orphan_frags_rx(skb2, GFP_ATOMIC))
2018 pt_prev->func(skb2, skb->dev, pt_prev, skb->dev);
2024 EXPORT_SYMBOL_GPL(dev_queue_xmit_nit);
2027 * netif_setup_tc - Handle tc mappings on real_num_tx_queues change
2028 * @dev: Network device
2029 * @txq: number of queues available
2031 * If real_num_tx_queues is changed the tc mappings may no longer be
2032 * valid. To resolve this verify the tc mapping remains valid and if
2033 * not NULL the mapping. With no priorities mapping to this
2034 * offset/count pair it will no longer be used. In the worst case TC0
2035 * is invalid nothing can be done so disable priority mappings. If is
2036 * expected that drivers will fix this mapping if they can before
2037 * calling netif_set_real_num_tx_queues.
2039 static void netif_setup_tc(struct net_device *dev, unsigned int txq)
2042 struct netdev_tc_txq *tc = &dev->tc_to_txq[0];
2044 /* If TC0 is invalidated disable TC mapping */
2045 if (tc->offset + tc->count > txq) {
2046 pr_warn("Number of in use tx queues changed invalidating tc mappings. Priority traffic classification disabled!\n");
2051 /* Invalidated prio to tc mappings set to TC0 */
2052 for (i = 1; i < TC_BITMASK + 1; i++) {
2053 int q = netdev_get_prio_tc_map(dev, i);
2055 tc = &dev->tc_to_txq[q];
2056 if (tc->offset + tc->count > txq) {
2057 pr_warn("Number of in use tx queues changed. Priority %i to tc mapping %i is no longer valid. Setting map to 0\n",
2059 netdev_set_prio_tc_map(dev, i, 0);
2064 int netdev_txq_to_tc(struct net_device *dev, unsigned int txq)
2067 struct netdev_tc_txq *tc = &dev->tc_to_txq[0];
2070 /* walk through the TCs and see if it falls into any of them */
2071 for (i = 0; i < TC_MAX_QUEUE; i++, tc++) {
2072 if ((txq - tc->offset) < tc->count)
2076 /* didn't find it, just return -1 to indicate no match */
2082 EXPORT_SYMBOL(netdev_txq_to_tc);
2085 struct static_key xps_needed __read_mostly;
2086 EXPORT_SYMBOL(xps_needed);
2087 struct static_key xps_rxqs_needed __read_mostly;
2088 EXPORT_SYMBOL(xps_rxqs_needed);
2089 static DEFINE_MUTEX(xps_map_mutex);
2090 #define xmap_dereference(P) \
2091 rcu_dereference_protected((P), lockdep_is_held(&xps_map_mutex))
2093 static bool remove_xps_queue(struct xps_dev_maps *dev_maps,
2096 struct xps_map *map = NULL;
2100 map = xmap_dereference(dev_maps->attr_map[tci]);
2104 for (pos = map->len; pos--;) {
2105 if (map->queues[pos] != index)
2109 map->queues[pos] = map->queues[--map->len];
2113 RCU_INIT_POINTER(dev_maps->attr_map[tci], NULL);
2114 kfree_rcu(map, rcu);
2121 static bool remove_xps_queue_cpu(struct net_device *dev,
2122 struct xps_dev_maps *dev_maps,
2123 int cpu, u16 offset, u16 count)
2125 int num_tc = dev->num_tc ? : 1;
2126 bool active = false;
2129 for (tci = cpu * num_tc; num_tc--; tci++) {
2132 for (i = count, j = offset; i--; j++) {
2133 if (!remove_xps_queue(dev_maps, tci, j))
2143 static void clean_xps_maps(struct net_device *dev, const unsigned long *mask,
2144 struct xps_dev_maps *dev_maps, unsigned int nr_ids,
2145 u16 offset, u16 count, bool is_rxqs_map)
2147 bool active = false;
2150 for (j = -1; j = netif_attrmask_next(j, mask, nr_ids),
2152 active |= remove_xps_queue_cpu(dev, dev_maps, j, offset,
2156 RCU_INIT_POINTER(dev->xps_rxqs_map, NULL);
2158 RCU_INIT_POINTER(dev->xps_cpus_map, NULL);
2160 for (i = offset + (count - 1); count--; i--)
2161 netdev_queue_numa_node_write(
2162 netdev_get_tx_queue(dev, i),
2165 kfree_rcu(dev_maps, rcu);
2169 static void netif_reset_xps_queues(struct net_device *dev, u16 offset,
2172 const unsigned long *possible_mask = NULL;
2173 struct xps_dev_maps *dev_maps;
2174 unsigned int nr_ids;
2176 if (!static_key_false(&xps_needed))
2179 mutex_lock(&xps_map_mutex);
2181 if (static_key_false(&xps_rxqs_needed)) {
2182 dev_maps = xmap_dereference(dev->xps_rxqs_map);
2184 nr_ids = dev->num_rx_queues;
2185 clean_xps_maps(dev, possible_mask, dev_maps, nr_ids,
2186 offset, count, true);
2190 dev_maps = xmap_dereference(dev->xps_cpus_map);
2194 if (num_possible_cpus() > 1)
2195 possible_mask = cpumask_bits(cpu_possible_mask);
2196 nr_ids = nr_cpu_ids;
2197 clean_xps_maps(dev, possible_mask, dev_maps, nr_ids, offset, count,
2201 if (static_key_enabled(&xps_rxqs_needed))
2202 static_key_slow_dec(&xps_rxqs_needed);
2204 static_key_slow_dec(&xps_needed);
2205 mutex_unlock(&xps_map_mutex);
2208 static void netif_reset_xps_queues_gt(struct net_device *dev, u16 index)
2210 netif_reset_xps_queues(dev, index, dev->num_tx_queues - index);
2213 static struct xps_map *expand_xps_map(struct xps_map *map, int attr_index,
2214 u16 index, bool is_rxqs_map)
2216 struct xps_map *new_map;
2217 int alloc_len = XPS_MIN_MAP_ALLOC;
2220 for (pos = 0; map && pos < map->len; pos++) {
2221 if (map->queues[pos] != index)
2226 /* Need to add tx-queue to this CPU's/rx-queue's existing map */
2228 if (pos < map->alloc_len)
2231 alloc_len = map->alloc_len * 2;
2234 /* Need to allocate new map to store tx-queue on this CPU's/rx-queue's
2238 new_map = kzalloc(XPS_MAP_SIZE(alloc_len), GFP_KERNEL);
2240 new_map = kzalloc_node(XPS_MAP_SIZE(alloc_len), GFP_KERNEL,
2241 cpu_to_node(attr_index));
2245 for (i = 0; i < pos; i++)
2246 new_map->queues[i] = map->queues[i];
2247 new_map->alloc_len = alloc_len;
2253 int __netif_set_xps_queue(struct net_device *dev, const unsigned long *mask,
2254 u16 index, bool is_rxqs_map)
2256 const unsigned long *online_mask = NULL, *possible_mask = NULL;
2257 struct xps_dev_maps *dev_maps, *new_dev_maps = NULL;
2258 int i, j, tci, numa_node_id = -2;
2259 int maps_sz, num_tc = 1, tc = 0;
2260 struct xps_map *map, *new_map;
2261 bool active = false;
2262 unsigned int nr_ids;
2265 /* Do not allow XPS on subordinate device directly */
2266 num_tc = dev->num_tc;
2270 /* If queue belongs to subordinate dev use its map */
2271 dev = netdev_get_tx_queue(dev, index)->sb_dev ? : dev;
2273 tc = netdev_txq_to_tc(dev, index);
2278 mutex_lock(&xps_map_mutex);
2280 maps_sz = XPS_RXQ_DEV_MAPS_SIZE(num_tc, dev->num_rx_queues);
2281 dev_maps = xmap_dereference(dev->xps_rxqs_map);
2282 nr_ids = dev->num_rx_queues;
2284 maps_sz = XPS_CPU_DEV_MAPS_SIZE(num_tc);
2285 if (num_possible_cpus() > 1) {
2286 online_mask = cpumask_bits(cpu_online_mask);
2287 possible_mask = cpumask_bits(cpu_possible_mask);
2289 dev_maps = xmap_dereference(dev->xps_cpus_map);
2290 nr_ids = nr_cpu_ids;
2293 if (maps_sz < L1_CACHE_BYTES)
2294 maps_sz = L1_CACHE_BYTES;
2296 /* allocate memory for queue storage */
2297 for (j = -1; j = netif_attrmask_next_and(j, online_mask, mask, nr_ids),
2300 new_dev_maps = kzalloc(maps_sz, GFP_KERNEL);
2301 if (!new_dev_maps) {
2302 mutex_unlock(&xps_map_mutex);
2306 tci = j * num_tc + tc;
2307 map = dev_maps ? xmap_dereference(dev_maps->attr_map[tci]) :
2310 map = expand_xps_map(map, j, index, is_rxqs_map);
2314 RCU_INIT_POINTER(new_dev_maps->attr_map[tci], map);
2318 goto out_no_new_maps;
2320 static_key_slow_inc(&xps_needed);
2322 static_key_slow_inc(&xps_rxqs_needed);
2324 for (j = -1; j = netif_attrmask_next(j, possible_mask, nr_ids),
2326 /* copy maps belonging to foreign traffic classes */
2327 for (i = tc, tci = j * num_tc; dev_maps && i--; tci++) {
2328 /* fill in the new device map from the old device map */
2329 map = xmap_dereference(dev_maps->attr_map[tci]);
2330 RCU_INIT_POINTER(new_dev_maps->attr_map[tci], map);
2333 /* We need to explicitly update tci as prevous loop
2334 * could break out early if dev_maps is NULL.
2336 tci = j * num_tc + tc;
2338 if (netif_attr_test_mask(j, mask, nr_ids) &&
2339 netif_attr_test_online(j, online_mask, nr_ids)) {
2340 /* add tx-queue to CPU/rx-queue maps */
2343 map = xmap_dereference(new_dev_maps->attr_map[tci]);
2344 while ((pos < map->len) && (map->queues[pos] != index))
2347 if (pos == map->len)
2348 map->queues[map->len++] = index;
2351 if (numa_node_id == -2)
2352 numa_node_id = cpu_to_node(j);
2353 else if (numa_node_id != cpu_to_node(j))
2357 } else if (dev_maps) {
2358 /* fill in the new device map from the old device map */
2359 map = xmap_dereference(dev_maps->attr_map[tci]);
2360 RCU_INIT_POINTER(new_dev_maps->attr_map[tci], map);
2363 /* copy maps belonging to foreign traffic classes */
2364 for (i = num_tc - tc, tci++; dev_maps && --i; tci++) {
2365 /* fill in the new device map from the old device map */
2366 map = xmap_dereference(dev_maps->attr_map[tci]);
2367 RCU_INIT_POINTER(new_dev_maps->attr_map[tci], map);
2372 rcu_assign_pointer(dev->xps_rxqs_map, new_dev_maps);
2374 rcu_assign_pointer(dev->xps_cpus_map, new_dev_maps);
2376 /* Cleanup old maps */
2378 goto out_no_old_maps;
2380 for (j = -1; j = netif_attrmask_next(j, possible_mask, nr_ids),
2382 for (i = num_tc, tci = j * num_tc; i--; tci++) {
2383 new_map = xmap_dereference(new_dev_maps->attr_map[tci]);
2384 map = xmap_dereference(dev_maps->attr_map[tci]);
2385 if (map && map != new_map)
2386 kfree_rcu(map, rcu);
2390 kfree_rcu(dev_maps, rcu);
2393 dev_maps = new_dev_maps;
2398 /* update Tx queue numa node */
2399 netdev_queue_numa_node_write(netdev_get_tx_queue(dev, index),
2400 (numa_node_id >= 0) ?
2401 numa_node_id : NUMA_NO_NODE);
2407 /* removes tx-queue from unused CPUs/rx-queues */
2408 for (j = -1; j = netif_attrmask_next(j, possible_mask, nr_ids),
2410 for (i = tc, tci = j * num_tc; i--; tci++)
2411 active |= remove_xps_queue(dev_maps, tci, index);
2412 if (!netif_attr_test_mask(j, mask, nr_ids) ||
2413 !netif_attr_test_online(j, online_mask, nr_ids))
2414 active |= remove_xps_queue(dev_maps, tci, index);
2415 for (i = num_tc - tc, tci++; --i; tci++)
2416 active |= remove_xps_queue(dev_maps, tci, index);
2419 /* free map if not active */
2422 RCU_INIT_POINTER(dev->xps_rxqs_map, NULL);
2424 RCU_INIT_POINTER(dev->xps_cpus_map, NULL);
2425 kfree_rcu(dev_maps, rcu);
2429 mutex_unlock(&xps_map_mutex);
2433 /* remove any maps that we added */
2434 for (j = -1; j = netif_attrmask_next(j, possible_mask, nr_ids),
2436 for (i = num_tc, tci = j * num_tc; i--; tci++) {
2437 new_map = xmap_dereference(new_dev_maps->attr_map[tci]);
2439 xmap_dereference(dev_maps->attr_map[tci]) :
2441 if (new_map && new_map != map)
2446 mutex_unlock(&xps_map_mutex);
2448 kfree(new_dev_maps);
2452 int netif_set_xps_queue(struct net_device *dev, const struct cpumask *mask,
2455 return __netif_set_xps_queue(dev, cpumask_bits(mask), index, false);
2457 EXPORT_SYMBOL(netif_set_xps_queue);
2460 static void netdev_unbind_all_sb_channels(struct net_device *dev)
2462 struct netdev_queue *txq = &dev->_tx[dev->num_tx_queues];
2464 /* Unbind any subordinate channels */
2465 while (txq-- != &dev->_tx[0]) {
2467 netdev_unbind_sb_channel(dev, txq->sb_dev);
2471 void netdev_reset_tc(struct net_device *dev)
2474 netif_reset_xps_queues_gt(dev, 0);
2476 netdev_unbind_all_sb_channels(dev);
2478 /* Reset TC configuration of device */
2480 memset(dev->tc_to_txq, 0, sizeof(dev->tc_to_txq));
2481 memset(dev->prio_tc_map, 0, sizeof(dev->prio_tc_map));
2483 EXPORT_SYMBOL(netdev_reset_tc);
2485 int netdev_set_tc_queue(struct net_device *dev, u8 tc, u16 count, u16 offset)
2487 if (tc >= dev->num_tc)
2491 netif_reset_xps_queues(dev, offset, count);
2493 dev->tc_to_txq[tc].count = count;
2494 dev->tc_to_txq[tc].offset = offset;
2497 EXPORT_SYMBOL(netdev_set_tc_queue);
2499 int netdev_set_num_tc(struct net_device *dev, u8 num_tc)
2501 if (num_tc > TC_MAX_QUEUE)
2505 netif_reset_xps_queues_gt(dev, 0);
2507 netdev_unbind_all_sb_channels(dev);
2509 dev->num_tc = num_tc;
2512 EXPORT_SYMBOL(netdev_set_num_tc);
2514 void netdev_unbind_sb_channel(struct net_device *dev,
2515 struct net_device *sb_dev)
2517 struct netdev_queue *txq = &dev->_tx[dev->num_tx_queues];
2520 netif_reset_xps_queues_gt(sb_dev, 0);
2522 memset(sb_dev->tc_to_txq, 0, sizeof(sb_dev->tc_to_txq));
2523 memset(sb_dev->prio_tc_map, 0, sizeof(sb_dev->prio_tc_map));
2525 while (txq-- != &dev->_tx[0]) {
2526 if (txq->sb_dev == sb_dev)
2530 EXPORT_SYMBOL(netdev_unbind_sb_channel);
2532 int netdev_bind_sb_channel_queue(struct net_device *dev,
2533 struct net_device *sb_dev,
2534 u8 tc, u16 count, u16 offset)
2536 /* Make certain the sb_dev and dev are already configured */
2537 if (sb_dev->num_tc >= 0 || tc >= dev->num_tc)
2540 /* We cannot hand out queues we don't have */
2541 if ((offset + count) > dev->real_num_tx_queues)
2544 /* Record the mapping */
2545 sb_dev->tc_to_txq[tc].count = count;
2546 sb_dev->tc_to_txq[tc].offset = offset;
2548 /* Provide a way for Tx queue to find the tc_to_txq map or
2549 * XPS map for itself.
2552 netdev_get_tx_queue(dev, count + offset)->sb_dev = sb_dev;
2556 EXPORT_SYMBOL(netdev_bind_sb_channel_queue);
2558 int netdev_set_sb_channel(struct net_device *dev, u16 channel)
2560 /* Do not use a multiqueue device to represent a subordinate channel */
2561 if (netif_is_multiqueue(dev))
2564 /* We allow channels 1 - 32767 to be used for subordinate channels.
2565 * Channel 0 is meant to be "native" mode and used only to represent
2566 * the main root device. We allow writing 0 to reset the device back
2567 * to normal mode after being used as a subordinate channel.
2569 if (channel > S16_MAX)
2572 dev->num_tc = -channel;
2576 EXPORT_SYMBOL(netdev_set_sb_channel);
2579 * Routine to help set real_num_tx_queues. To avoid skbs mapped to queues
2580 * greater than real_num_tx_queues stale skbs on the qdisc must be flushed.
2582 int netif_set_real_num_tx_queues(struct net_device *dev, unsigned int txq)
2587 disabling = txq < dev->real_num_tx_queues;
2589 if (txq < 1 || txq > dev->num_tx_queues)
2592 if (dev->reg_state == NETREG_REGISTERED ||
2593 dev->reg_state == NETREG_UNREGISTERING) {
2596 rc = netdev_queue_update_kobjects(dev, dev->real_num_tx_queues,
2602 netif_setup_tc(dev, txq);
2604 dev->real_num_tx_queues = txq;
2608 qdisc_reset_all_tx_gt(dev, txq);
2610 netif_reset_xps_queues_gt(dev, txq);
2614 dev->real_num_tx_queues = txq;
2619 EXPORT_SYMBOL(netif_set_real_num_tx_queues);
2623 * netif_set_real_num_rx_queues - set actual number of RX queues used
2624 * @dev: Network device
2625 * @rxq: Actual number of RX queues
2627 * This must be called either with the rtnl_lock held or before
2628 * registration of the net device. Returns 0 on success, or a
2629 * negative error code. If called before registration, it always
2632 int netif_set_real_num_rx_queues(struct net_device *dev, unsigned int rxq)
2636 if (rxq < 1 || rxq > dev->num_rx_queues)
2639 if (dev->reg_state == NETREG_REGISTERED) {
2642 rc = net_rx_queue_update_kobjects(dev, dev->real_num_rx_queues,
2648 dev->real_num_rx_queues = rxq;
2651 EXPORT_SYMBOL(netif_set_real_num_rx_queues);
2655 * netif_get_num_default_rss_queues - default number of RSS queues
2657 * This routine should set an upper limit on the number of RSS queues
2658 * used by default by multiqueue devices.
2660 int netif_get_num_default_rss_queues(void)
2662 return is_kdump_kernel() ?
2663 1 : min_t(int, DEFAULT_MAX_NUM_RSS_QUEUES, num_online_cpus());
2665 EXPORT_SYMBOL(netif_get_num_default_rss_queues);
2667 static void __netif_reschedule(struct Qdisc *q)
2669 struct softnet_data *sd;
2670 unsigned long flags;
2672 local_irq_save(flags);
2673 sd = this_cpu_ptr(&softnet_data);
2674 q->next_sched = NULL;
2675 *sd->output_queue_tailp = q;
2676 sd->output_queue_tailp = &q->next_sched;
2677 raise_softirq_irqoff(NET_TX_SOFTIRQ);
2678 local_irq_restore(flags);
2681 void __netif_schedule(struct Qdisc *q)
2683 if (!test_and_set_bit(__QDISC_STATE_SCHED, &q->state))
2684 __netif_reschedule(q);
2686 EXPORT_SYMBOL(__netif_schedule);
2688 struct dev_kfree_skb_cb {
2689 enum skb_free_reason reason;
2692 static struct dev_kfree_skb_cb *get_kfree_skb_cb(const struct sk_buff *skb)
2694 return (struct dev_kfree_skb_cb *)skb->cb;
2697 void netif_schedule_queue(struct netdev_queue *txq)
2700 if (!(txq->state & QUEUE_STATE_ANY_XOFF)) {
2701 struct Qdisc *q = rcu_dereference(txq->qdisc);
2703 __netif_schedule(q);
2707 EXPORT_SYMBOL(netif_schedule_queue);
2709 void netif_tx_wake_queue(struct netdev_queue *dev_queue)
2711 if (test_and_clear_bit(__QUEUE_STATE_DRV_XOFF, &dev_queue->state)) {
2715 q = rcu_dereference(dev_queue->qdisc);
2716 __netif_schedule(q);
2720 EXPORT_SYMBOL(netif_tx_wake_queue);
2722 void __dev_kfree_skb_irq(struct sk_buff *skb, enum skb_free_reason reason)
2724 unsigned long flags;
2729 if (likely(refcount_read(&skb->users) == 1)) {
2731 refcount_set(&skb->users, 0);
2732 } else if (likely(!refcount_dec_and_test(&skb->users))) {
2735 get_kfree_skb_cb(skb)->reason = reason;
2736 local_irq_save(flags);
2737 skb->next = __this_cpu_read(softnet_data.completion_queue);
2738 __this_cpu_write(softnet_data.completion_queue, skb);
2739 raise_softirq_irqoff(NET_TX_SOFTIRQ);
2740 local_irq_restore(flags);
2742 EXPORT_SYMBOL(__dev_kfree_skb_irq);
2744 void __dev_kfree_skb_any(struct sk_buff *skb, enum skb_free_reason reason)
2746 if (in_irq() || irqs_disabled())
2747 __dev_kfree_skb_irq(skb, reason);
2751 EXPORT_SYMBOL(__dev_kfree_skb_any);
2755 * netif_device_detach - mark device as removed
2756 * @dev: network device
2758 * Mark device as removed from system and therefore no longer available.
2760 void netif_device_detach(struct net_device *dev)
2762 if (test_and_clear_bit(__LINK_STATE_PRESENT, &dev->state) &&
2763 netif_running(dev)) {
2764 netif_tx_stop_all_queues(dev);
2767 EXPORT_SYMBOL(netif_device_detach);
2770 * netif_device_attach - mark device as attached
2771 * @dev: network device
2773 * Mark device as attached from system and restart if needed.
2775 void netif_device_attach(struct net_device *dev)
2777 if (!test_and_set_bit(__LINK_STATE_PRESENT, &dev->state) &&
2778 netif_running(dev)) {
2779 netif_tx_wake_all_queues(dev);
2780 __netdev_watchdog_up(dev);
2783 EXPORT_SYMBOL(netif_device_attach);
2786 * Returns a Tx hash based on the given packet descriptor a Tx queues' number
2787 * to be used as a distribution range.
2789 static u16 skb_tx_hash(const struct net_device *dev,
2790 const struct net_device *sb_dev,
2791 struct sk_buff *skb)
2795 u16 qcount = dev->real_num_tx_queues;
2798 u8 tc = netdev_get_prio_tc_map(dev, skb->priority);
2800 qoffset = sb_dev->tc_to_txq[tc].offset;
2801 qcount = sb_dev->tc_to_txq[tc].count;
2804 if (skb_rx_queue_recorded(skb)) {
2805 hash = skb_get_rx_queue(skb);
2806 while (unlikely(hash >= qcount))
2808 return hash + qoffset;
2811 return (u16) reciprocal_scale(skb_get_hash(skb), qcount) + qoffset;
2814 static void skb_warn_bad_offload(const struct sk_buff *skb)
2816 static const netdev_features_t null_features;
2817 struct net_device *dev = skb->dev;
2818 const char *name = "";
2820 if (!net_ratelimit())
2824 if (dev->dev.parent)
2825 name = dev_driver_string(dev->dev.parent);
2827 name = netdev_name(dev);
2829 WARN(1, "%s: caps=(%pNF, %pNF) len=%d data_len=%d gso_size=%d "
2830 "gso_type=%d ip_summed=%d\n",
2831 name, dev ? &dev->features : &null_features,
2832 skb->sk ? &skb->sk->sk_route_caps : &null_features,
2833 skb->len, skb->data_len, skb_shinfo(skb)->gso_size,
2834 skb_shinfo(skb)->gso_type, skb->ip_summed);
2838 * Invalidate hardware checksum when packet is to be mangled, and
2839 * complete checksum manually on outgoing path.
2841 int skb_checksum_help(struct sk_buff *skb)
2844 int ret = 0, offset;
2846 if (skb->ip_summed == CHECKSUM_COMPLETE)
2847 goto out_set_summed;
2849 if (unlikely(skb_shinfo(skb)->gso_size)) {
2850 skb_warn_bad_offload(skb);
2854 /* Before computing a checksum, we should make sure no frag could
2855 * be modified by an external entity : checksum could be wrong.
2857 if (skb_has_shared_frag(skb)) {
2858 ret = __skb_linearize(skb);
2863 offset = skb_checksum_start_offset(skb);
2864 BUG_ON(offset >= skb_headlen(skb));
2865 csum = skb_checksum(skb, offset, skb->len - offset, 0);
2867 offset += skb->csum_offset;
2868 BUG_ON(offset + sizeof(__sum16) > skb_headlen(skb));
2870 if (skb_cloned(skb) &&
2871 !skb_clone_writable(skb, offset + sizeof(__sum16))) {
2872 ret = pskb_expand_head(skb, 0, 0, GFP_ATOMIC);
2877 *(__sum16 *)(skb->data + offset) = csum_fold(csum) ?: CSUM_MANGLED_0;
2879 skb->ip_summed = CHECKSUM_NONE;
2883 EXPORT_SYMBOL(skb_checksum_help);
2885 int skb_crc32c_csum_help(struct sk_buff *skb)
2888 int ret = 0, offset, start;
2890 if (skb->ip_summed != CHECKSUM_PARTIAL)
2893 if (unlikely(skb_is_gso(skb)))
2896 /* Before computing a checksum, we should make sure no frag could
2897 * be modified by an external entity : checksum could be wrong.
2899 if (unlikely(skb_has_shared_frag(skb))) {
2900 ret = __skb_linearize(skb);
2904 start = skb_checksum_start_offset(skb);
2905 offset = start + offsetof(struct sctphdr, checksum);
2906 if (WARN_ON_ONCE(offset >= skb_headlen(skb))) {
2910 if (skb_cloned(skb) &&
2911 !skb_clone_writable(skb, offset + sizeof(__le32))) {
2912 ret = pskb_expand_head(skb, 0, 0, GFP_ATOMIC);
2916 crc32c_csum = cpu_to_le32(~__skb_checksum(skb, start,
2917 skb->len - start, ~(__u32)0,
2919 *(__le32 *)(skb->data + offset) = crc32c_csum;
2920 skb->ip_summed = CHECKSUM_NONE;
2921 skb->csum_not_inet = 0;
2926 __be16 skb_network_protocol(struct sk_buff *skb, int *depth)
2928 __be16 type = skb->protocol;
2930 /* Tunnel gso handlers can set protocol to ethernet. */
2931 if (type == htons(ETH_P_TEB)) {
2934 if (unlikely(!pskb_may_pull(skb, sizeof(struct ethhdr))))
2937 eth = (struct ethhdr *)skb->data;
2938 type = eth->h_proto;
2941 return __vlan_get_protocol(skb, type, depth);
2945 * skb_mac_gso_segment - mac layer segmentation handler.
2946 * @skb: buffer to segment
2947 * @features: features for the output path (see dev->features)
2949 struct sk_buff *skb_mac_gso_segment(struct sk_buff *skb,
2950 netdev_features_t features)
2952 struct sk_buff *segs = ERR_PTR(-EPROTONOSUPPORT);
2953 struct packet_offload *ptype;
2954 int vlan_depth = skb->mac_len;
2955 __be16 type = skb_network_protocol(skb, &vlan_depth);
2957 if (unlikely(!type))
2958 return ERR_PTR(-EINVAL);
2960 __skb_pull(skb, vlan_depth);
2963 list_for_each_entry_rcu(ptype, &offload_base, list) {
2964 if (ptype->type == type && ptype->callbacks.gso_segment) {
2965 segs = ptype->callbacks.gso_segment(skb, features);
2971 __skb_push(skb, skb->data - skb_mac_header(skb));
2975 EXPORT_SYMBOL(skb_mac_gso_segment);
2978 /* openvswitch calls this on rx path, so we need a different check.
2980 static inline bool skb_needs_check(struct sk_buff *skb, bool tx_path)
2983 return skb->ip_summed != CHECKSUM_PARTIAL &&
2984 skb->ip_summed != CHECKSUM_UNNECESSARY;
2986 return skb->ip_summed == CHECKSUM_NONE;
2990 * __skb_gso_segment - Perform segmentation on skb.
2991 * @skb: buffer to segment
2992 * @features: features for the output path (see dev->features)
2993 * @tx_path: whether it is called in TX path
2995 * This function segments the given skb and returns a list of segments.
2997 * It may return NULL if the skb requires no segmentation. This is
2998 * only possible when GSO is used for verifying header integrity.
3000 * Segmentation preserves SKB_SGO_CB_OFFSET bytes of previous skb cb.
3002 struct sk_buff *__skb_gso_segment(struct sk_buff *skb,
3003 netdev_features_t features, bool tx_path)
3005 struct sk_buff *segs;
3007 if (unlikely(skb_needs_check(skb, tx_path))) {
3010 /* We're going to init ->check field in TCP or UDP header */
3011 err = skb_cow_head(skb, 0);
3013 return ERR_PTR(err);
3016 /* Only report GSO partial support if it will enable us to
3017 * support segmentation on this frame without needing additional
3020 if (features & NETIF_F_GSO_PARTIAL) {
3021 netdev_features_t partial_features = NETIF_F_GSO_ROBUST;
3022 struct net_device *dev = skb->dev;
3024 partial_features |= dev->features & dev->gso_partial_features;
3025 if (!skb_gso_ok(skb, features | partial_features))
3026 features &= ~NETIF_F_GSO_PARTIAL;
3029 BUILD_BUG_ON(SKB_SGO_CB_OFFSET +
3030 sizeof(*SKB_GSO_CB(skb)) > sizeof(skb->cb));
3032 SKB_GSO_CB(skb)->mac_offset = skb_headroom(skb);
3033 SKB_GSO_CB(skb)->encap_level = 0;
3035 skb_reset_mac_header(skb);
3036 skb_reset_mac_len(skb);
3038 segs = skb_mac_gso_segment(skb, features);
3040 if (unlikely(skb_needs_check(skb, tx_path) && !IS_ERR(segs)))
3041 skb_warn_bad_offload(skb);
3045 EXPORT_SYMBOL(__skb_gso_segment);
3047 /* Take action when hardware reception checksum errors are detected. */
3049 void netdev_rx_csum_fault(struct net_device *dev)
3051 if (net_ratelimit()) {
3052 pr_err("%s: hw csum failure\n", dev ? dev->name : "<unknown>");
3056 EXPORT_SYMBOL(netdev_rx_csum_fault);
3059 /* XXX: check that highmem exists at all on the given machine. */
3060 static int illegal_highdma(struct net_device *dev, struct sk_buff *skb)
3062 #ifdef CONFIG_HIGHMEM
3065 if (!(dev->features & NETIF_F_HIGHDMA)) {
3066 for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
3067 skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
3069 if (PageHighMem(skb_frag_page(frag)))
3077 /* If MPLS offload request, verify we are testing hardware MPLS features
3078 * instead of standard features for the netdev.
3080 #if IS_ENABLED(CONFIG_NET_MPLS_GSO)
3081 static netdev_features_t net_mpls_features(struct sk_buff *skb,
3082 netdev_features_t features,
3085 if (eth_p_mpls(type))
3086 features &= skb->dev->mpls_features;
3091 static netdev_features_t net_mpls_features(struct sk_buff *skb,
3092 netdev_features_t features,
3099 static netdev_features_t harmonize_features(struct sk_buff *skb,
3100 netdev_features_t features)
3105 type = skb_network_protocol(skb, &tmp);
3106 features = net_mpls_features(skb, features, type);
3108 if (skb->ip_summed != CHECKSUM_NONE &&
3109 !can_checksum_protocol(features, type)) {
3110 features &= ~(NETIF_F_CSUM_MASK | NETIF_F_GSO_MASK);
3112 if (illegal_highdma(skb->dev, skb))
3113 features &= ~NETIF_F_SG;
3118 netdev_features_t passthru_features_check(struct sk_buff *skb,
3119 struct net_device *dev,
3120 netdev_features_t features)
3124 EXPORT_SYMBOL(passthru_features_check);
3126 static netdev_features_t dflt_features_check(struct sk_buff *skb,
3127 struct net_device *dev,
3128 netdev_features_t features)
3130 return vlan_features_check(skb, features);
3133 static netdev_features_t gso_features_check(const struct sk_buff *skb,
3134 struct net_device *dev,
3135 netdev_features_t features)
3137 u16 gso_segs = skb_shinfo(skb)->gso_segs;
3139 if (gso_segs > dev->gso_max_segs)
3140 return features & ~NETIF_F_GSO_MASK;
3142 /* Support for GSO partial features requires software
3143 * intervention before we can actually process the packets
3144 * so we need to strip support for any partial features now
3145 * and we can pull them back in after we have partially
3146 * segmented the frame.
3148 if (!(skb_shinfo(skb)->gso_type & SKB_GSO_PARTIAL))
3149 features &= ~dev->gso_partial_features;
3151 /* Make sure to clear the IPv4 ID mangling feature if the
3152 * IPv4 header has the potential to be fragmented.
3154 if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV4) {
3155 struct iphdr *iph = skb->encapsulation ?
3156 inner_ip_hdr(skb) : ip_hdr(skb);
3158 if (!(iph->frag_off & htons(IP_DF)))
3159 features &= ~NETIF_F_TSO_MANGLEID;
3165 netdev_features_t netif_skb_features(struct sk_buff *skb)
3167 struct net_device *dev = skb->dev;
3168 netdev_features_t features = dev->features;
3170 if (skb_is_gso(skb))
3171 features = gso_features_check(skb, dev, features);
3173 /* If encapsulation offload request, verify we are testing
3174 * hardware encapsulation features instead of standard
3175 * features for the netdev
3177 if (skb->encapsulation)
3178 features &= dev->hw_enc_features;
3180 if (skb_vlan_tagged(skb))
3181 features = netdev_intersect_features(features,
3182 dev->vlan_features |
3183 NETIF_F_HW_VLAN_CTAG_TX |
3184 NETIF_F_HW_VLAN_STAG_TX);
3186 if (dev->netdev_ops->ndo_features_check)
3187 features &= dev->netdev_ops->ndo_features_check(skb, dev,
3190 features &= dflt_features_check(skb, dev, features);
3192 return harmonize_features(skb, features);
3194 EXPORT_SYMBOL(netif_skb_features);
3196 static int xmit_one(struct sk_buff *skb, struct net_device *dev,
3197 struct netdev_queue *txq, bool more)
3202 if (!list_empty(&ptype_all) || !list_empty(&dev->ptype_all))
3203 dev_queue_xmit_nit(skb, dev);
3206 trace_net_dev_start_xmit(skb, dev);
3207 rc = netdev_start_xmit(skb, dev, txq, more);
3208 trace_net_dev_xmit(skb, rc, dev, len);
3213 struct sk_buff *dev_hard_start_xmit(struct sk_buff *first, struct net_device *dev,
3214 struct netdev_queue *txq, int *ret)
3216 struct sk_buff *skb = first;
3217 int rc = NETDEV_TX_OK;
3220 struct sk_buff *next = skb->next;
3223 rc = xmit_one(skb, dev, txq, next != NULL);
3224 if (unlikely(!dev_xmit_complete(rc))) {
3230 if (netif_xmit_stopped(txq) && skb) {
3231 rc = NETDEV_TX_BUSY;
3241 static struct sk_buff *validate_xmit_vlan(struct sk_buff *skb,
3242 netdev_features_t features)
3244 if (skb_vlan_tag_present(skb) &&
3245 !vlan_hw_offload_capable(features, skb->vlan_proto))
3246 skb = __vlan_hwaccel_push_inside(skb);
3250 int skb_csum_hwoffload_help(struct sk_buff *skb,
3251 const netdev_features_t features)
3253 if (unlikely(skb->csum_not_inet))
3254 return !!(features & NETIF_F_SCTP_CRC) ? 0 :
3255 skb_crc32c_csum_help(skb);
3257 return !!(features & NETIF_F_CSUM_MASK) ? 0 : skb_checksum_help(skb);
3259 EXPORT_SYMBOL(skb_csum_hwoffload_help);
3261 static struct sk_buff *validate_xmit_skb(struct sk_buff *skb, struct net_device *dev, bool *again)
3263 netdev_features_t features;
3265 features = netif_skb_features(skb);
3266 skb = validate_xmit_vlan(skb, features);
3270 skb = sk_validate_xmit_skb(skb, dev);
3274 if (netif_needs_gso(skb, features)) {
3275 struct sk_buff *segs;
3277 segs = skb_gso_segment(skb, features);
3285 if (skb_needs_linearize(skb, features) &&
3286 __skb_linearize(skb))
3289 /* If packet is not checksummed and device does not
3290 * support checksumming for this protocol, complete
3291 * checksumming here.
3293 if (skb->ip_summed == CHECKSUM_PARTIAL) {
3294 if (skb->encapsulation)
3295 skb_set_inner_transport_header(skb,
3296 skb_checksum_start_offset(skb));
3298 skb_set_transport_header(skb,
3299 skb_checksum_start_offset(skb));
3300 if (skb_csum_hwoffload_help(skb, features))
3305 skb = validate_xmit_xfrm(skb, features, again);
3312 atomic_long_inc(&dev->tx_dropped);
3316 struct sk_buff *validate_xmit_skb_list(struct sk_buff *skb, struct net_device *dev, bool *again)
3318 struct sk_buff *next, *head = NULL, *tail;
3320 for (; skb != NULL; skb = next) {
3324 /* in case skb wont be segmented, point to itself */
3327 skb = validate_xmit_skb(skb, dev, again);
3335 /* If skb was segmented, skb->prev points to
3336 * the last segment. If not, it still contains skb.
3342 EXPORT_SYMBOL_GPL(validate_xmit_skb_list);
3344 static void qdisc_pkt_len_init(struct sk_buff *skb)
3346 const struct skb_shared_info *shinfo = skb_shinfo(skb);
3348 qdisc_skb_cb(skb)->pkt_len = skb->len;
3350 /* To get more precise estimation of bytes sent on wire,
3351 * we add to pkt_len the headers size of all segments
3353 if (shinfo->gso_size) {
3354 unsigned int hdr_len;
3355 u16 gso_segs = shinfo->gso_segs;
3357 /* mac layer + network layer */
3358 hdr_len = skb_transport_header(skb) - skb_mac_header(skb);
3360 /* + transport layer */
3361 if (likely(shinfo->gso_type & (SKB_GSO_TCPV4 | SKB_GSO_TCPV6))) {
3362 const struct tcphdr *th;
3363 struct tcphdr _tcphdr;
3365 th = skb_header_pointer(skb, skb_transport_offset(skb),
3366 sizeof(_tcphdr), &_tcphdr);
3368 hdr_len += __tcp_hdrlen(th);
3370 struct udphdr _udphdr;
3372 if (skb_header_pointer(skb, skb_transport_offset(skb),
3373 sizeof(_udphdr), &_udphdr))
3374 hdr_len += sizeof(struct udphdr);
3377 if (shinfo->gso_type & SKB_GSO_DODGY)
3378 gso_segs = DIV_ROUND_UP(skb->len - hdr_len,
3381 qdisc_skb_cb(skb)->pkt_len += (gso_segs - 1) * hdr_len;
3385 static inline int __dev_xmit_skb(struct sk_buff *skb, struct Qdisc *q,
3386 struct net_device *dev,
3387 struct netdev_queue *txq)
3389 spinlock_t *root_lock = qdisc_lock(q);
3390 struct sk_buff *to_free = NULL;
3394 qdisc_calculate_pkt_len(skb, q);
3396 if (q->flags & TCQ_F_NOLOCK) {
3397 if (unlikely(test_bit(__QDISC_STATE_DEACTIVATED, &q->state))) {
3398 __qdisc_drop(skb, &to_free);
3401 rc = q->enqueue(skb, q, &to_free) & NET_XMIT_MASK;
3405 if (unlikely(to_free))
3406 kfree_skb_list(to_free);
3411 * Heuristic to force contended enqueues to serialize on a
3412 * separate lock before trying to get qdisc main lock.
3413 * This permits qdisc->running owner to get the lock more
3414 * often and dequeue packets faster.
3416 contended = qdisc_is_running(q);
3417 if (unlikely(contended))
3418 spin_lock(&q->busylock);
3420 spin_lock(root_lock);
3421 if (unlikely(test_bit(__QDISC_STATE_DEACTIVATED, &q->state))) {
3422 __qdisc_drop(skb, &to_free);
3424 } else if ((q->flags & TCQ_F_CAN_BYPASS) && !qdisc_qlen(q) &&
3425 qdisc_run_begin(q)) {
3427 * This is a work-conserving queue; there are no old skbs
3428 * waiting to be sent out; and the qdisc is not running -
3429 * xmit the skb directly.
3432 qdisc_bstats_update(q, skb);
3434 if (sch_direct_xmit(skb, q, dev, txq, root_lock, true)) {
3435 if (unlikely(contended)) {
3436 spin_unlock(&q->busylock);
3443 rc = NET_XMIT_SUCCESS;
3445 rc = q->enqueue(skb, q, &to_free) & NET_XMIT_MASK;
3446 if (qdisc_run_begin(q)) {
3447 if (unlikely(contended)) {
3448 spin_unlock(&q->busylock);
3455 spin_unlock(root_lock);
3456 if (unlikely(to_free))
3457 kfree_skb_list(to_free);
3458 if (unlikely(contended))
3459 spin_unlock(&q->busylock);
3463 #if IS_ENABLED(CONFIG_CGROUP_NET_PRIO)
3464 static void skb_update_prio(struct sk_buff *skb)
3466 const struct netprio_map *map;
3467 const struct sock *sk;
3468 unsigned int prioidx;
3472 map = rcu_dereference_bh(skb->dev->priomap);
3475 sk = skb_to_full_sk(skb);
3479 prioidx = sock_cgroup_prioidx(&sk->sk_cgrp_data);
3481 if (prioidx < map->priomap_len)
3482 skb->priority = map->priomap[prioidx];
3485 #define skb_update_prio(skb)
3488 DEFINE_PER_CPU(int, xmit_recursion);
3489 EXPORT_SYMBOL(xmit_recursion);
3492 * dev_loopback_xmit - loop back @skb
3493 * @net: network namespace this loopback is happening in
3494 * @sk: sk needed to be a netfilter okfn
3495 * @skb: buffer to transmit
3497 int dev_loopback_xmit(struct net *net, struct sock *sk, struct sk_buff *skb)
3499 skb_reset_mac_header(skb);
3500 __skb_pull(skb, skb_network_offset(skb));
3501 skb->pkt_type = PACKET_LOOPBACK;
3502 skb->ip_summed = CHECKSUM_UNNECESSARY;
3503 WARN_ON(!skb_dst(skb));
3508 EXPORT_SYMBOL(dev_loopback_xmit);
3510 #ifdef CONFIG_NET_EGRESS
3511 static struct sk_buff *
3512 sch_handle_egress(struct sk_buff *skb, int *ret, struct net_device *dev)
3514 struct mini_Qdisc *miniq = rcu_dereference_bh(dev->miniq_egress);
3515 struct tcf_result cl_res;
3520 /* qdisc_skb_cb(skb)->pkt_len was already set by the caller. */
3521 mini_qdisc_bstats_cpu_update(miniq, skb);
3523 switch (tcf_classify(skb, miniq->filter_list, &cl_res, false)) {
3525 case TC_ACT_RECLASSIFY:
3526 skb->tc_index = TC_H_MIN(cl_res.classid);
3529 mini_qdisc_qstats_cpu_drop(miniq);
3530 *ret = NET_XMIT_DROP;
3536 *ret = NET_XMIT_SUCCESS;
3539 case TC_ACT_REDIRECT:
3540 /* No need to push/pop skb's mac_header here on egress! */
3541 skb_do_redirect(skb);
3542 *ret = NET_XMIT_SUCCESS;
3550 #endif /* CONFIG_NET_EGRESS */
3553 static int __get_xps_queue_idx(struct net_device *dev, struct sk_buff *skb,
3554 struct xps_dev_maps *dev_maps, unsigned int tci)
3556 struct xps_map *map;
3557 int queue_index = -1;
3561 tci += netdev_get_prio_tc_map(dev, skb->priority);
3564 map = rcu_dereference(dev_maps->attr_map[tci]);
3567 queue_index = map->queues[0];
3569 queue_index = map->queues[reciprocal_scale(
3570 skb_get_hash(skb), map->len)];
3571 if (unlikely(queue_index >= dev->real_num_tx_queues))
3578 static int get_xps_queue(struct net_device *dev, struct net_device *sb_dev,
3579 struct sk_buff *skb)
3582 struct xps_dev_maps *dev_maps;
3583 struct sock *sk = skb->sk;
3584 int queue_index = -1;
3586 if (!static_key_false(&xps_needed))
3590 if (!static_key_false(&xps_rxqs_needed))
3593 dev_maps = rcu_dereference(sb_dev->xps_rxqs_map);
3595 int tci = sk_rx_queue_get(sk);
3597 if (tci >= 0 && tci < dev->num_rx_queues)
3598 queue_index = __get_xps_queue_idx(dev, skb, dev_maps,
3603 if (queue_index < 0) {
3604 dev_maps = rcu_dereference(sb_dev->xps_cpus_map);
3606 unsigned int tci = skb->sender_cpu - 1;
3608 queue_index = __get_xps_queue_idx(dev, skb, dev_maps,
3620 static u16 ___netdev_pick_tx(struct net_device *dev, struct sk_buff *skb,
3621 struct net_device *sb_dev)
3623 struct sock *sk = skb->sk;
3624 int queue_index = sk_tx_queue_get(sk);
3626 sb_dev = sb_dev ? : dev;
3628 if (queue_index < 0 || skb->ooo_okay ||
3629 queue_index >= dev->real_num_tx_queues) {
3630 int new_index = get_xps_queue(dev, sb_dev, skb);
3633 new_index = skb_tx_hash(dev, sb_dev, skb);
3635 if (queue_index != new_index && sk &&
3637 rcu_access_pointer(sk->sk_dst_cache))
3638 sk_tx_queue_set(sk, new_index);
3640 queue_index = new_index;
3646 static u16 __netdev_pick_tx(struct net_device *dev,
3647 struct sk_buff *skb)
3649 return ___netdev_pick_tx(dev, skb, NULL);
3652 struct netdev_queue *netdev_pick_tx(struct net_device *dev,
3653 struct sk_buff *skb,
3654 struct net_device *sb_dev)
3656 int queue_index = 0;
3659 u32 sender_cpu = skb->sender_cpu - 1;
3661 if (sender_cpu >= (u32)NR_CPUS)
3662 skb->sender_cpu = raw_smp_processor_id() + 1;
3665 if (dev->real_num_tx_queues != 1) {
3666 const struct net_device_ops *ops = dev->netdev_ops;
3668 if (ops->ndo_select_queue)
3669 queue_index = ops->ndo_select_queue(dev, skb, sb_dev,
3672 queue_index = ___netdev_pick_tx(dev, skb, sb_dev);
3674 queue_index = netdev_cap_txqueue(dev, queue_index);
3677 skb_set_queue_mapping(skb, queue_index);
3678 return netdev_get_tx_queue(dev, queue_index);
3682 * __dev_queue_xmit - transmit a buffer
3683 * @skb: buffer to transmit
3684 * @sb_dev: suboordinate device used for L2 forwarding offload
3686 * Queue a buffer for transmission to a network device. The caller must
3687 * have set the device and priority and built the buffer before calling
3688 * this function. The function can be called from an interrupt.
3690 * A negative errno code is returned on a failure. A success does not
3691 * guarantee the frame will be transmitted as it may be dropped due
3692 * to congestion or traffic shaping.
3694 * -----------------------------------------------------------------------------------
3695 * I notice this method can also return errors from the queue disciplines,
3696 * including NET_XMIT_DROP, which is a positive value. So, errors can also
3699 * Regardless of the return value, the skb is consumed, so it is currently
3700 * difficult to retry a send to this method. (You can bump the ref count
3701 * before sending to hold a reference for retry if you are careful.)
3703 * When calling this method, interrupts MUST be enabled. This is because
3704 * the BH enable code must have IRQs enabled so that it will not deadlock.
3707 static int __dev_queue_xmit(struct sk_buff *skb, struct net_device *sb_dev)
3709 struct net_device *dev = skb->dev;
3710 struct netdev_queue *txq;
3715 skb_reset_mac_header(skb);
3717 if (unlikely(skb_shinfo(skb)->tx_flags & SKBTX_SCHED_TSTAMP))
3718 __skb_tstamp_tx(skb, NULL, skb->sk, SCM_TSTAMP_SCHED);
3720 /* Disable soft irqs for various locks below. Also
3721 * stops preemption for RCU.
3725 skb_update_prio(skb);
3727 qdisc_pkt_len_init(skb);
3728 #ifdef CONFIG_NET_CLS_ACT
3729 skb->tc_at_ingress = 0;
3730 # ifdef CONFIG_NET_EGRESS
3731 if (static_branch_unlikely(&egress_needed_key)) {
3732 skb = sch_handle_egress(skb, &rc, dev);
3738 /* If device/qdisc don't need skb->dst, release it right now while
3739 * its hot in this cpu cache.
3741 if (dev->priv_flags & IFF_XMIT_DST_RELEASE)
3746 txq = netdev_pick_tx(dev, skb, sb_dev);
3747 q = rcu_dereference_bh(txq->qdisc);
3749 trace_net_dev_queue(skb);
3751 rc = __dev_xmit_skb(skb, q, dev, txq);
3755 /* The device has no queue. Common case for software devices:
3756 * loopback, all the sorts of tunnels...
3758 * Really, it is unlikely that netif_tx_lock protection is necessary
3759 * here. (f.e. loopback and IP tunnels are clean ignoring statistics
3761 * However, it is possible, that they rely on protection
3764 * Check this and shot the lock. It is not prone from deadlocks.
3765 *Either shot noqueue qdisc, it is even simpler 8)
3767 if (dev->flags & IFF_UP) {
3768 int cpu = smp_processor_id(); /* ok because BHs are off */
3770 if (txq->xmit_lock_owner != cpu) {
3771 if (unlikely(__this_cpu_read(xmit_recursion) >
3772 XMIT_RECURSION_LIMIT))
3773 goto recursion_alert;
3775 skb = validate_xmit_skb(skb, dev, &again);
3779 HARD_TX_LOCK(dev, txq, cpu);
3781 if (!netif_xmit_stopped(txq)) {
3782 __this_cpu_inc(xmit_recursion);
3783 skb = dev_hard_start_xmit(skb, dev, txq, &rc);
3784 __this_cpu_dec(xmit_recursion);
3785 if (dev_xmit_complete(rc)) {
3786 HARD_TX_UNLOCK(dev, txq);
3790 HARD_TX_UNLOCK(dev, txq);
3791 net_crit_ratelimited("Virtual device %s asks to queue packet!\n",
3794 /* Recursion is detected! It is possible,
3798 net_crit_ratelimited("Dead loop on virtual device %s, fix it urgently!\n",
3804 rcu_read_unlock_bh();
3806 atomic_long_inc(&dev->tx_dropped);
3807 kfree_skb_list(skb);
3810 rcu_read_unlock_bh();
3814 int dev_queue_xmit(struct sk_buff *skb)
3816 return __dev_queue_xmit(skb, NULL);
3818 EXPORT_SYMBOL(dev_queue_xmit);
3820 int dev_queue_xmit_accel(struct sk_buff *skb, struct net_device *sb_dev)
3822 return __dev_queue_xmit(skb, sb_dev);
3824 EXPORT_SYMBOL(dev_queue_xmit_accel);
3826 int dev_direct_xmit(struct sk_buff *skb, u16 queue_id)
3828 struct net_device *dev = skb->dev;
3829 struct sk_buff *orig_skb = skb;
3830 struct netdev_queue *txq;
3831 int ret = NETDEV_TX_BUSY;
3834 if (unlikely(!netif_running(dev) ||
3835 !netif_carrier_ok(dev)))
3838 skb = validate_xmit_skb_list(skb, dev, &again);
3839 if (skb != orig_skb)
3842 skb_set_queue_mapping(skb, queue_id);
3843 txq = skb_get_tx_queue(dev, skb);
3847 HARD_TX_LOCK(dev, txq, smp_processor_id());
3848 if (!netif_xmit_frozen_or_drv_stopped(txq))
3849 ret = netdev_start_xmit(skb, dev, txq, false);
3850 HARD_TX_UNLOCK(dev, txq);
3854 if (!dev_xmit_complete(ret))
3859 atomic_long_inc(&dev->tx_dropped);
3860 kfree_skb_list(skb);
3861 return NET_XMIT_DROP;
3863 EXPORT_SYMBOL(dev_direct_xmit);
3865 /*************************************************************************
3867 *************************************************************************/
3869 int netdev_max_backlog __read_mostly = 1000;
3870 EXPORT_SYMBOL(netdev_max_backlog);
3872 int netdev_tstamp_prequeue __read_mostly = 1;
3873 int netdev_budget __read_mostly = 300;
3874 unsigned int __read_mostly netdev_budget_usecs = 2000;
3875 int weight_p __read_mostly = 64; /* old backlog weight */
3876 int dev_weight_rx_bias __read_mostly = 1; /* bias for backlog weight */
3877 int dev_weight_tx_bias __read_mostly = 1; /* bias for output_queue quota */
3878 int dev_rx_weight __read_mostly = 64;
3879 int dev_tx_weight __read_mostly = 64;
3881 /* Called with irq disabled */
3882 static inline void ____napi_schedule(struct softnet_data *sd,
3883 struct napi_struct *napi)
3885 list_add_tail(&napi->poll_list, &sd->poll_list);
3886 __raise_softirq_irqoff(NET_RX_SOFTIRQ);
3891 /* One global table that all flow-based protocols share. */
3892 struct rps_sock_flow_table __rcu *rps_sock_flow_table __read_mostly;
3893 EXPORT_SYMBOL(rps_sock_flow_table);
3894 u32 rps_cpu_mask __read_mostly;
3895 EXPORT_SYMBOL(rps_cpu_mask);
3897 struct static_key rps_needed __read_mostly;
3898 EXPORT_SYMBOL(rps_needed);
3899 struct static_key rfs_needed __read_mostly;
3900 EXPORT_SYMBOL(rfs_needed);
3902 static struct rps_dev_flow *
3903 set_rps_cpu(struct net_device *dev, struct sk_buff *skb,
3904 struct rps_dev_flow *rflow, u16 next_cpu)
3906 if (next_cpu < nr_cpu_ids) {
3907 #ifdef CONFIG_RFS_ACCEL
3908 struct netdev_rx_queue *rxqueue;
3909 struct rps_dev_flow_table *flow_table;
3910 struct rps_dev_flow *old_rflow;
3915 /* Should we steer this flow to a different hardware queue? */
3916 if (!skb_rx_queue_recorded(skb) || !dev->rx_cpu_rmap ||
3917 !(dev->features & NETIF_F_NTUPLE))
3919 rxq_index = cpu_rmap_lookup_index(dev->rx_cpu_rmap, next_cpu);
3920 if (rxq_index == skb_get_rx_queue(skb))
3923 rxqueue = dev->_rx + rxq_index;
3924 flow_table = rcu_dereference(rxqueue->rps_flow_table);
3927 flow_id = skb_get_hash(skb) & flow_table->mask;
3928 rc = dev->netdev_ops->ndo_rx_flow_steer(dev, skb,
3929 rxq_index, flow_id);
3933 rflow = &flow_table->flows[flow_id];
3935 if (old_rflow->filter == rflow->filter)
3936 old_rflow->filter = RPS_NO_FILTER;
3940 per_cpu(softnet_data, next_cpu).input_queue_head;
3943 rflow->cpu = next_cpu;
3948 * get_rps_cpu is called from netif_receive_skb and returns the target
3949 * CPU from the RPS map of the receiving queue for a given skb.
3950 * rcu_read_lock must be held on entry.
3952 static int get_rps_cpu(struct net_device *dev, struct sk_buff *skb,
3953 struct rps_dev_flow **rflowp)
3955 const struct rps_sock_flow_table *sock_flow_table;
3956 struct netdev_rx_queue *rxqueue = dev->_rx;
3957 struct rps_dev_flow_table *flow_table;
3958 struct rps_map *map;
3963 if (skb_rx_queue_recorded(skb)) {
3964 u16 index = skb_get_rx_queue(skb);
3966 if (unlikely(index >= dev->real_num_rx_queues)) {
3967 WARN_ONCE(dev->real_num_rx_queues > 1,
3968 "%s received packet on queue %u, but number "
3969 "of RX queues is %u\n",
3970 dev->name, index, dev->real_num_rx_queues);
3976 /* Avoid computing hash if RFS/RPS is not active for this rxqueue */
3978 flow_table = rcu_dereference(rxqueue->rps_flow_table);
3979 map = rcu_dereference(rxqueue->rps_map);
3980 if (!flow_table && !map)
3983 skb_reset_network_header(skb);
3984 hash = skb_get_hash(skb);
3988 sock_flow_table = rcu_dereference(rps_sock_flow_table);
3989 if (flow_table && sock_flow_table) {
3990 struct rps_dev_flow *rflow;
3994 /* First check into global flow table if there is a match */
3995 ident = sock_flow_table->ents[hash & sock_flow_table->mask];
3996 if ((ident ^ hash) & ~rps_cpu_mask)
3999 next_cpu = ident & rps_cpu_mask;
4001 /* OK, now we know there is a match,
4002 * we can look at the local (per receive queue) flow table
4004 rflow = &flow_table->flows[hash & flow_table->mask];
4008 * If the desired CPU (where last recvmsg was done) is
4009 * different from current CPU (one in the rx-queue flow
4010 * table entry), switch if one of the following holds:
4011 * - Current CPU is unset (>= nr_cpu_ids).
4012 * - Current CPU is offline.
4013 * - The current CPU's queue tail has advanced beyond the
4014 * last packet that was enqueued using this table entry.
4015 * This guarantees that all previous packets for the flow
4016 * have been dequeued, thus preserving in order delivery.
4018 if (unlikely(tcpu != next_cpu) &&
4019 (tcpu >= nr_cpu_ids || !cpu_online(tcpu) ||
4020 ((int)(per_cpu(softnet_data, tcpu).input_queue_head -
4021 rflow->last_qtail)) >= 0)) {
4023 rflow = set_rps_cpu(dev, skb, rflow, next_cpu);
4026 if (tcpu < nr_cpu_ids && cpu_online(tcpu)) {
4036 tcpu = map->cpus[reciprocal_scale(hash, map->len)];
4037 if (cpu_online(tcpu)) {
4047 #ifdef CONFIG_RFS_ACCEL
4050 * rps_may_expire_flow - check whether an RFS hardware filter may be removed
4051 * @dev: Device on which the filter was set
4052 * @rxq_index: RX queue index
4053 * @flow_id: Flow ID passed to ndo_rx_flow_steer()
4054 * @filter_id: Filter ID returned by ndo_rx_flow_steer()
4056 * Drivers that implement ndo_rx_flow_steer() should periodically call
4057 * this function for each installed filter and remove the filters for
4058 * which it returns %true.
4060 bool rps_may_expire_flow(struct net_device *dev, u16 rxq_index,
4061 u32 flow_id, u16 filter_id)
4063 struct netdev_rx_queue *rxqueue = dev->_rx + rxq_index;
4064 struct rps_dev_flow_table *flow_table;
4065 struct rps_dev_flow *rflow;
4070 flow_table = rcu_dereference(rxqueue->rps_flow_table);
4071 if (flow_table && flow_id <= flow_table->mask) {
4072 rflow = &flow_table->flows[flow_id];
4073 cpu = READ_ONCE(rflow->cpu);
4074 if (rflow->filter == filter_id && cpu < nr_cpu_ids &&
4075 ((int)(per_cpu(softnet_data, cpu).input_queue_head -
4076 rflow->last_qtail) <
4077 (int)(10 * flow_table->mask)))
4083 EXPORT_SYMBOL(rps_may_expire_flow);
4085 #endif /* CONFIG_RFS_ACCEL */
4087 /* Called from hardirq (IPI) context */
4088 static void rps_trigger_softirq(void *data)
4090 struct softnet_data *sd = data;
4092 ____napi_schedule(sd, &sd->backlog);
4096 #endif /* CONFIG_RPS */
4099 * Check if this softnet_data structure is another cpu one
4100 * If yes, queue it to our IPI list and return 1
4103 static int rps_ipi_queued(struct softnet_data *sd)
4106 struct softnet_data *mysd = this_cpu_ptr(&softnet_data);
4109 sd->rps_ipi_next = mysd->rps_ipi_list;
4110 mysd->rps_ipi_list = sd;
4112 __raise_softirq_irqoff(NET_RX_SOFTIRQ);
4115 #endif /* CONFIG_RPS */
4119 #ifdef CONFIG_NET_FLOW_LIMIT
4120 int netdev_flow_limit_table_len __read_mostly = (1 << 12);
4123 static bool skb_flow_limit(struct sk_buff *skb, unsigned int qlen)
4125 #ifdef CONFIG_NET_FLOW_LIMIT
4126 struct sd_flow_limit *fl;
4127 struct softnet_data *sd;
4128 unsigned int old_flow, new_flow;
4130 if (qlen < (netdev_max_backlog >> 1))
4133 sd = this_cpu_ptr(&softnet_data);
4136 fl = rcu_dereference(sd->flow_limit);
4138 new_flow = skb_get_hash(skb) & (fl->num_buckets - 1);
4139 old_flow = fl->history[fl->history_head];
4140 fl->history[fl->history_head] = new_flow;
4143 fl->history_head &= FLOW_LIMIT_HISTORY - 1;
4145 if (likely(fl->buckets[old_flow]))
4146 fl->buckets[old_flow]--;
4148 if (++fl->buckets[new_flow] > (FLOW_LIMIT_HISTORY >> 1)) {
4160 * enqueue_to_backlog is called to queue an skb to a per CPU backlog
4161 * queue (may be a remote CPU queue).
4163 static int enqueue_to_backlog(struct sk_buff *skb, int cpu,
4164 unsigned int *qtail)
4166 struct softnet_data *sd;
4167 unsigned long flags;
4170 sd = &per_cpu(softnet_data, cpu);
4172 local_irq_save(flags);
4175 if (!netif_running(skb->dev))
4177 qlen = skb_queue_len(&sd->input_pkt_queue);
4178 if (qlen <= netdev_max_backlog && !skb_flow_limit(skb, qlen)) {
4181 __skb_queue_tail(&sd->input_pkt_queue, skb);
4182 input_queue_tail_incr_save(sd, qtail);
4184 local_irq_restore(flags);
4185 return NET_RX_SUCCESS;
4188 /* Schedule NAPI for backlog device
4189 * We can use non atomic operation since we own the queue lock
4191 if (!__test_and_set_bit(NAPI_STATE_SCHED, &sd->backlog.state)) {
4192 if (!rps_ipi_queued(sd))
4193 ____napi_schedule(sd, &sd->backlog);
4202 local_irq_restore(flags);
4204 atomic_long_inc(&skb->dev->rx_dropped);
4209 static struct netdev_rx_queue *netif_get_rxqueue(struct sk_buff *skb)
4211 struct net_device *dev = skb->dev;
4212 struct netdev_rx_queue *rxqueue;
4216 if (skb_rx_queue_recorded(skb)) {
4217 u16 index = skb_get_rx_queue(skb);
4219 if (unlikely(index >= dev->real_num_rx_queues)) {
4220 WARN_ONCE(dev->real_num_rx_queues > 1,
4221 "%s received packet on queue %u, but number "
4222 "of RX queues is %u\n",
4223 dev->name, index, dev->real_num_rx_queues);
4225 return rxqueue; /* Return first rxqueue */
4232 static u32 netif_receive_generic_xdp(struct sk_buff *skb,
4233 struct xdp_buff *xdp,
4234 struct bpf_prog *xdp_prog)
4236 struct netdev_rx_queue *rxqueue;
4237 void *orig_data, *orig_data_end;
4238 u32 metalen, act = XDP_DROP;
4242 /* Reinjected packets coming from act_mirred or similar should
4243 * not get XDP generic processing.
4245 if (skb_cloned(skb))
4248 /* XDP packets must be linear and must have sufficient headroom
4249 * of XDP_PACKET_HEADROOM bytes. This is the guarantee that also
4250 * native XDP provides, thus we need to do it here as well.
4252 if (skb_is_nonlinear(skb) ||
4253 skb_headroom(skb) < XDP_PACKET_HEADROOM) {
4254 int hroom = XDP_PACKET_HEADROOM - skb_headroom(skb);
4255 int troom = skb->tail + skb->data_len - skb->end;
4257 /* In case we have to go down the path and also linearize,
4258 * then lets do the pskb_expand_head() work just once here.
4260 if (pskb_expand_head(skb,
4261 hroom > 0 ? ALIGN(hroom, NET_SKB_PAD) : 0,
4262 troom > 0 ? troom + 128 : 0, GFP_ATOMIC))
4264 if (skb_linearize(skb))
4268 /* The XDP program wants to see the packet starting at the MAC
4271 mac_len = skb->data - skb_mac_header(skb);
4272 hlen = skb_headlen(skb) + mac_len;
4273 xdp->data = skb->data - mac_len;
4274 xdp->data_meta = xdp->data;
4275 xdp->data_end = xdp->data + hlen;
4276 xdp->data_hard_start = skb->data - skb_headroom(skb);
4277 orig_data_end = xdp->data_end;
4278 orig_data = xdp->data;
4280 rxqueue = netif_get_rxqueue(skb);
4281 xdp->rxq = &rxqueue->xdp_rxq;
4283 act = bpf_prog_run_xdp(xdp_prog, xdp);
4285 off = xdp->data - orig_data;
4287 __skb_pull(skb, off);
4289 __skb_push(skb, -off);
4290 skb->mac_header += off;
4292 /* check if bpf_xdp_adjust_tail was used. it can only "shrink"
4295 off = orig_data_end - xdp->data_end;
4297 skb_set_tail_pointer(skb, xdp->data_end - xdp->data);
4305 __skb_push(skb, mac_len);
4308 metalen = xdp->data - xdp->data_meta;
4310 skb_metadata_set(skb, metalen);
4313 bpf_warn_invalid_xdp_action(act);
4316 trace_xdp_exception(skb->dev, xdp_prog, act);
4327 /* When doing generic XDP we have to bypass the qdisc layer and the
4328 * network taps in order to match in-driver-XDP behavior.
4330 void generic_xdp_tx(struct sk_buff *skb, struct bpf_prog *xdp_prog)
4332 struct net_device *dev = skb->dev;
4333 struct netdev_queue *txq;
4334 bool free_skb = true;
4337 txq = netdev_pick_tx(dev, skb, NULL);
4338 cpu = smp_processor_id();
4339 HARD_TX_LOCK(dev, txq, cpu);
4340 if (!netif_xmit_stopped(txq)) {
4341 rc = netdev_start_xmit(skb, dev, txq, 0);
4342 if (dev_xmit_complete(rc))
4345 HARD_TX_UNLOCK(dev, txq);
4347 trace_xdp_exception(dev, xdp_prog, XDP_TX);
4351 EXPORT_SYMBOL_GPL(generic_xdp_tx);
4353 static DEFINE_STATIC_KEY_FALSE(generic_xdp_needed_key);
4355 int do_xdp_generic(struct bpf_prog *xdp_prog, struct sk_buff *skb)
4358 struct xdp_buff xdp;
4362 act = netif_receive_generic_xdp(skb, &xdp, xdp_prog);
4363 if (act != XDP_PASS) {
4366 err = xdp_do_generic_redirect(skb->dev, skb,
4372 generic_xdp_tx(skb, xdp_prog);
4383 EXPORT_SYMBOL_GPL(do_xdp_generic);
4385 static int netif_rx_internal(struct sk_buff *skb)
4389 net_timestamp_check(netdev_tstamp_prequeue, skb);
4391 trace_netif_rx(skb);
4393 if (static_branch_unlikely(&generic_xdp_needed_key)) {
4398 ret = do_xdp_generic(rcu_dereference(skb->dev->xdp_prog), skb);
4402 /* Consider XDP consuming the packet a success from
4403 * the netdev point of view we do not want to count
4406 if (ret != XDP_PASS)
4407 return NET_RX_SUCCESS;
4411 if (static_key_false(&rps_needed)) {
4412 struct rps_dev_flow voidflow, *rflow = &voidflow;
4418 cpu = get_rps_cpu(skb->dev, skb, &rflow);
4420 cpu = smp_processor_id();
4422 ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail);
4431 ret = enqueue_to_backlog(skb, get_cpu(), &qtail);
4438 * netif_rx - post buffer to the network code
4439 * @skb: buffer to post
4441 * This function receives a packet from a device driver and queues it for
4442 * the upper (protocol) levels to process. It always succeeds. The buffer
4443 * may be dropped during processing for congestion control or by the
4447 * NET_RX_SUCCESS (no congestion)
4448 * NET_RX_DROP (packet was dropped)
4452 int netif_rx(struct sk_buff *skb)
4454 trace_netif_rx_entry(skb);
4456 return netif_rx_internal(skb);
4458 EXPORT_SYMBOL(netif_rx);
4460 int netif_rx_ni(struct sk_buff *skb)
4464 trace_netif_rx_ni_entry(skb);
4467 err = netif_rx_internal(skb);
4468 if (local_softirq_pending())
4474 EXPORT_SYMBOL(netif_rx_ni);
4476 static __latent_entropy void net_tx_action(struct softirq_action *h)
4478 struct softnet_data *sd = this_cpu_ptr(&softnet_data);
4480 if (sd->completion_queue) {
4481 struct sk_buff *clist;
4483 local_irq_disable();
4484 clist = sd->completion_queue;
4485 sd->completion_queue = NULL;
4489 struct sk_buff *skb = clist;
4491 clist = clist->next;
4493 WARN_ON(refcount_read(&skb->users));
4494 if (likely(get_kfree_skb_cb(skb)->reason == SKB_REASON_CONSUMED))
4495 trace_consume_skb(skb);
4497 trace_kfree_skb(skb, net_tx_action);
4499 if (skb->fclone != SKB_FCLONE_UNAVAILABLE)
4502 __kfree_skb_defer(skb);
4505 __kfree_skb_flush();
4508 if (sd->output_queue) {
4511 local_irq_disable();
4512 head = sd->output_queue;
4513 sd->output_queue = NULL;
4514 sd->output_queue_tailp = &sd->output_queue;
4518 struct Qdisc *q = head;
4519 spinlock_t *root_lock = NULL;
4521 head = head->next_sched;
4523 if (!(q->flags & TCQ_F_NOLOCK)) {
4524 root_lock = qdisc_lock(q);
4525 spin_lock(root_lock);
4527 /* We need to make sure head->next_sched is read
4528 * before clearing __QDISC_STATE_SCHED
4530 smp_mb__before_atomic();
4531 clear_bit(__QDISC_STATE_SCHED, &q->state);
4534 spin_unlock(root_lock);
4538 xfrm_dev_backlog(sd);
4541 #if IS_ENABLED(CONFIG_BRIDGE) && IS_ENABLED(CONFIG_ATM_LANE)
4542 /* This hook is defined here for ATM LANE */
4543 int (*br_fdb_test_addr_hook)(struct net_device *dev,
4544 unsigned char *addr) __read_mostly;
4545 EXPORT_SYMBOL_GPL(br_fdb_test_addr_hook);
4548 static inline struct sk_buff *
4549 sch_handle_ingress(struct sk_buff *skb, struct packet_type **pt_prev, int *ret,
4550 struct net_device *orig_dev)
4552 #ifdef CONFIG_NET_CLS_ACT
4553 struct mini_Qdisc *miniq = rcu_dereference_bh(skb->dev->miniq_ingress);
4554 struct tcf_result cl_res;
4556 /* If there's at least one ingress present somewhere (so
4557 * we get here via enabled static key), remaining devices
4558 * that are not configured with an ingress qdisc will bail
4565 *ret = deliver_skb(skb, *pt_prev, orig_dev);
4569 qdisc_skb_cb(skb)->pkt_len = skb->len;
4570 skb->tc_at_ingress = 1;
4571 mini_qdisc_bstats_cpu_update(miniq, skb);
4573 switch (tcf_classify(skb, miniq->filter_list, &cl_res, false)) {
4575 case TC_ACT_RECLASSIFY:
4576 skb->tc_index = TC_H_MIN(cl_res.classid);
4579 mini_qdisc_qstats_cpu_drop(miniq);
4587 case TC_ACT_REDIRECT:
4588 /* skb_mac_header check was done by cls/act_bpf, so
4589 * we can safely push the L2 header back before
4590 * redirecting to another netdev
4592 __skb_push(skb, skb->mac_len);
4593 skb_do_redirect(skb);
4598 #endif /* CONFIG_NET_CLS_ACT */
4603 * netdev_is_rx_handler_busy - check if receive handler is registered
4604 * @dev: device to check
4606 * Check if a receive handler is already registered for a given device.
4607 * Return true if there one.
4609 * The caller must hold the rtnl_mutex.
4611 bool netdev_is_rx_handler_busy(struct net_device *dev)
4614 return dev && rtnl_dereference(dev->rx_handler);
4616 EXPORT_SYMBOL_GPL(netdev_is_rx_handler_busy);
4619 * netdev_rx_handler_register - register receive handler
4620 * @dev: device to register a handler for
4621 * @rx_handler: receive handler to register
4622 * @rx_handler_data: data pointer that is used by rx handler
4624 * Register a receive handler for a device. This handler will then be
4625 * called from __netif_receive_skb. A negative errno code is returned
4628 * The caller must hold the rtnl_mutex.
4630 * For a general description of rx_handler, see enum rx_handler_result.
4632 int netdev_rx_handler_register(struct net_device *dev,
4633 rx_handler_func_t *rx_handler,
4634 void *rx_handler_data)
4636 if (netdev_is_rx_handler_busy(dev))
4639 if (dev->priv_flags & IFF_NO_RX_HANDLER)
4642 /* Note: rx_handler_data must be set before rx_handler */
4643 rcu_assign_pointer(dev->rx_handler_data, rx_handler_data);
4644 rcu_assign_pointer(dev->rx_handler, rx_handler);
4648 EXPORT_SYMBOL_GPL(netdev_rx_handler_register);
4651 * netdev_rx_handler_unregister - unregister receive handler
4652 * @dev: device to unregister a handler from
4654 * Unregister a receive handler from a device.
4656 * The caller must hold the rtnl_mutex.
4658 void netdev_rx_handler_unregister(struct net_device *dev)
4662 RCU_INIT_POINTER(dev->rx_handler, NULL);
4663 /* a reader seeing a non NULL rx_handler in a rcu_read_lock()
4664 * section has a guarantee to see a non NULL rx_handler_data
4668 RCU_INIT_POINTER(dev->rx_handler_data, NULL);
4670 EXPORT_SYMBOL_GPL(netdev_rx_handler_unregister);
4673 * Limit the use of PFMEMALLOC reserves to those protocols that implement
4674 * the special handling of PFMEMALLOC skbs.
4676 static bool skb_pfmemalloc_protocol(struct sk_buff *skb)
4678 switch (skb->protocol) {
4679 case htons(ETH_P_ARP):
4680 case htons(ETH_P_IP):
4681 case htons(ETH_P_IPV6):
4682 case htons(ETH_P_8021Q):
4683 case htons(ETH_P_8021AD):
4690 static inline int nf_ingress(struct sk_buff *skb, struct packet_type **pt_prev,
4691 int *ret, struct net_device *orig_dev)
4693 #ifdef CONFIG_NETFILTER_INGRESS
4694 if (nf_hook_ingress_active(skb)) {
4698 *ret = deliver_skb(skb, *pt_prev, orig_dev);
4703 ingress_retval = nf_hook_ingress(skb);
4705 return ingress_retval;
4707 #endif /* CONFIG_NETFILTER_INGRESS */
4711 static int __netif_receive_skb_core(struct sk_buff *skb, bool pfmemalloc,
4712 struct packet_type **ppt_prev)
4714 struct packet_type *ptype, *pt_prev;
4715 rx_handler_func_t *rx_handler;
4716 struct net_device *orig_dev;
4717 bool deliver_exact = false;
4718 int ret = NET_RX_DROP;
4721 net_timestamp_check(!netdev_tstamp_prequeue, skb);
4723 trace_netif_receive_skb(skb);
4725 orig_dev = skb->dev;
4727 skb_reset_network_header(skb);
4728 if (!skb_transport_header_was_set(skb))
4729 skb_reset_transport_header(skb);
4730 skb_reset_mac_len(skb);
4735 skb->skb_iif = skb->dev->ifindex;
4737 __this_cpu_inc(softnet_data.processed);
4739 if (skb->protocol == cpu_to_be16(ETH_P_8021Q) ||
4740 skb->protocol == cpu_to_be16(ETH_P_8021AD)) {
4741 skb = skb_vlan_untag(skb);
4746 if (skb_skip_tc_classify(skb))
4752 list_for_each_entry_rcu(ptype, &ptype_all, list) {
4754 ret = deliver_skb(skb, pt_prev, orig_dev);
4758 list_for_each_entry_rcu(ptype, &skb->dev->ptype_all, list) {
4760 ret = deliver_skb(skb, pt_prev, orig_dev);
4765 #ifdef CONFIG_NET_INGRESS
4766 if (static_branch_unlikely(&ingress_needed_key)) {
4767 skb = sch_handle_ingress(skb, &pt_prev, &ret, orig_dev);
4771 if (nf_ingress(skb, &pt_prev, &ret, orig_dev) < 0)
4777 if (pfmemalloc && !skb_pfmemalloc_protocol(skb))
4780 if (skb_vlan_tag_present(skb)) {
4782 ret = deliver_skb(skb, pt_prev, orig_dev);
4785 if (vlan_do_receive(&skb))
4787 else if (unlikely(!skb))
4791 rx_handler = rcu_dereference(skb->dev->rx_handler);
4794 ret = deliver_skb(skb, pt_prev, orig_dev);
4797 switch (rx_handler(&skb)) {
4798 case RX_HANDLER_CONSUMED:
4799 ret = NET_RX_SUCCESS;
4801 case RX_HANDLER_ANOTHER:
4803 case RX_HANDLER_EXACT:
4804 deliver_exact = true;
4805 case RX_HANDLER_PASS:
4812 if (unlikely(skb_vlan_tag_present(skb))) {
4813 if (skb_vlan_tag_get_id(skb))
4814 skb->pkt_type = PACKET_OTHERHOST;
4815 /* Note: we might in the future use prio bits
4816 * and set skb->priority like in vlan_do_receive()
4817 * For the time being, just ignore Priority Code Point
4822 type = skb->protocol;
4824 /* deliver only exact match when indicated */
4825 if (likely(!deliver_exact)) {
4826 deliver_ptype_list_skb(skb, &pt_prev, orig_dev, type,
4827 &ptype_base[ntohs(type) &
4831 deliver_ptype_list_skb(skb, &pt_prev, orig_dev, type,
4832 &orig_dev->ptype_specific);
4834 if (unlikely(skb->dev != orig_dev)) {
4835 deliver_ptype_list_skb(skb, &pt_prev, orig_dev, type,
4836 &skb->dev->ptype_specific);
4840 if (unlikely(skb_orphan_frags_rx(skb, GFP_ATOMIC)))
4842 *ppt_prev = pt_prev;
4846 atomic_long_inc(&skb->dev->rx_dropped);
4848 atomic_long_inc(&skb->dev->rx_nohandler);
4850 /* Jamal, now you will not able to escape explaining
4851 * me how you were going to use this. :-)
4860 static int __netif_receive_skb_one_core(struct sk_buff *skb, bool pfmemalloc)
4862 struct net_device *orig_dev = skb->dev;
4863 struct packet_type *pt_prev = NULL;
4866 ret = __netif_receive_skb_core(skb, pfmemalloc, &pt_prev);
4868 ret = pt_prev->func(skb, skb->dev, pt_prev, orig_dev);
4873 * netif_receive_skb_core - special purpose version of netif_receive_skb
4874 * @skb: buffer to process
4876 * More direct receive version of netif_receive_skb(). It should
4877 * only be used by callers that have a need to skip RPS and Generic XDP.
4878 * Caller must also take care of handling if (page_is_)pfmemalloc.
4880 * This function may only be called from softirq context and interrupts
4881 * should be enabled.
4883 * Return values (usually ignored):
4884 * NET_RX_SUCCESS: no congestion
4885 * NET_RX_DROP: packet was dropped
4887 int netif_receive_skb_core(struct sk_buff *skb)
4892 ret = __netif_receive_skb_one_core(skb, false);
4897 EXPORT_SYMBOL(netif_receive_skb_core);
4899 static inline void __netif_receive_skb_list_ptype(struct list_head *head,
4900 struct packet_type *pt_prev,
4901 struct net_device *orig_dev)
4903 struct sk_buff *skb, *next;
4907 if (list_empty(head))
4909 if (pt_prev->list_func != NULL)
4910 pt_prev->list_func(head, pt_prev, orig_dev);
4912 list_for_each_entry_safe(skb, next, head, list)
4913 pt_prev->func(skb, skb->dev, pt_prev, orig_dev);
4916 static void __netif_receive_skb_list_core(struct list_head *head, bool pfmemalloc)
4918 /* Fast-path assumptions:
4919 * - There is no RX handler.
4920 * - Only one packet_type matches.
4921 * If either of these fails, we will end up doing some per-packet
4922 * processing in-line, then handling the 'last ptype' for the whole
4923 * sublist. This can't cause out-of-order delivery to any single ptype,
4924 * because the 'last ptype' must be constant across the sublist, and all
4925 * other ptypes are handled per-packet.
4927 /* Current (common) ptype of sublist */
4928 struct packet_type *pt_curr = NULL;
4929 /* Current (common) orig_dev of sublist */
4930 struct net_device *od_curr = NULL;
4931 struct list_head sublist;
4932 struct sk_buff *skb, *next;
4934 list_for_each_entry_safe(skb, next, head, list) {
4935 struct net_device *orig_dev = skb->dev;
4936 struct packet_type *pt_prev = NULL;
4938 __netif_receive_skb_core(skb, pfmemalloc, &pt_prev);
4939 if (pt_curr != pt_prev || od_curr != orig_dev) {
4940 /* dispatch old sublist */
4941 list_cut_before(&sublist, head, &skb->list);
4942 __netif_receive_skb_list_ptype(&sublist, pt_curr, od_curr);
4943 /* start new sublist */
4949 /* dispatch final sublist */
4950 __netif_receive_skb_list_ptype(head, pt_curr, od_curr);
4953 static int __netif_receive_skb(struct sk_buff *skb)
4957 if (sk_memalloc_socks() && skb_pfmemalloc(skb)) {
4958 unsigned int noreclaim_flag;
4961 * PFMEMALLOC skbs are special, they should
4962 * - be delivered to SOCK_MEMALLOC sockets only
4963 * - stay away from userspace
4964 * - have bounded memory usage
4966 * Use PF_MEMALLOC as this saves us from propagating the allocation
4967 * context down to all allocation sites.
4969 noreclaim_flag = memalloc_noreclaim_save();
4970 ret = __netif_receive_skb_one_core(skb, true);
4971 memalloc_noreclaim_restore(noreclaim_flag);
4973 ret = __netif_receive_skb_one_core(skb, false);
4978 static void __netif_receive_skb_list(struct list_head *head)
4980 unsigned long noreclaim_flag = 0;
4981 struct sk_buff *skb, *next;
4982 bool pfmemalloc = false; /* Is current sublist PF_MEMALLOC? */
4984 list_for_each_entry_safe(skb, next, head, list) {
4985 if ((sk_memalloc_socks() && skb_pfmemalloc(skb)) != pfmemalloc) {
4986 struct list_head sublist;
4988 /* Handle the previous sublist */
4989 list_cut_before(&sublist, head, &skb->list);
4990 if (!list_empty(&sublist))
4991 __netif_receive_skb_list_core(&sublist, pfmemalloc);
4992 pfmemalloc = !pfmemalloc;
4993 /* See comments in __netif_receive_skb */
4995 noreclaim_flag = memalloc_noreclaim_save();
4997 memalloc_noreclaim_restore(noreclaim_flag);
5000 /* Handle the remaining sublist */
5001 if (!list_empty(head))
5002 __netif_receive_skb_list_core(head, pfmemalloc);
5003 /* Restore pflags */
5005 memalloc_noreclaim_restore(noreclaim_flag);
5008 static int generic_xdp_install(struct net_device *dev, struct netdev_bpf *xdp)
5010 struct bpf_prog *old = rtnl_dereference(dev->xdp_prog);
5011 struct bpf_prog *new = xdp->prog;
5014 switch (xdp->command) {
5015 case XDP_SETUP_PROG:
5016 rcu_assign_pointer(dev->xdp_prog, new);
5021 static_branch_dec(&generic_xdp_needed_key);
5022 } else if (new && !old) {
5023 static_branch_inc(&generic_xdp_needed_key);
5024 dev_disable_lro(dev);
5025 dev_disable_gro_hw(dev);
5029 case XDP_QUERY_PROG:
5030 xdp->prog_attached = !!old;
5031 xdp->prog_id = old ? old->aux->id : 0;
5042 static int netif_receive_skb_internal(struct sk_buff *skb)
5046 net_timestamp_check(netdev_tstamp_prequeue, skb);
5048 if (skb_defer_rx_timestamp(skb))
5049 return NET_RX_SUCCESS;
5051 if (static_branch_unlikely(&generic_xdp_needed_key)) {
5056 ret = do_xdp_generic(rcu_dereference(skb->dev->xdp_prog), skb);
5060 if (ret != XDP_PASS)
5066 if (static_key_false(&rps_needed)) {
5067 struct rps_dev_flow voidflow, *rflow = &voidflow;
5068 int cpu = get_rps_cpu(skb->dev, skb, &rflow);
5071 ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail);
5077 ret = __netif_receive_skb(skb);
5082 static void netif_receive_skb_list_internal(struct list_head *head)
5084 struct bpf_prog *xdp_prog = NULL;
5085 struct sk_buff *skb, *next;
5087 list_for_each_entry_safe(skb, next, head, list) {
5088 net_timestamp_check(netdev_tstamp_prequeue, skb);
5089 if (skb_defer_rx_timestamp(skb))
5090 /* Handled, remove from list */
5091 list_del(&skb->list);
5094 if (static_branch_unlikely(&generic_xdp_needed_key)) {
5097 list_for_each_entry_safe(skb, next, head, list) {
5098 xdp_prog = rcu_dereference(skb->dev->xdp_prog);
5099 if (do_xdp_generic(xdp_prog, skb) != XDP_PASS)
5100 /* Dropped, remove from list */
5101 list_del(&skb->list);
5109 if (static_key_false(&rps_needed)) {
5110 list_for_each_entry_safe(skb, next, head, list) {
5111 struct rps_dev_flow voidflow, *rflow = &voidflow;
5112 int cpu = get_rps_cpu(skb->dev, skb, &rflow);
5115 enqueue_to_backlog(skb, cpu, &rflow->last_qtail);
5116 /* Handled, remove from list */
5117 list_del(&skb->list);
5122 __netif_receive_skb_list(head);
5127 * netif_receive_skb - process receive buffer from network
5128 * @skb: buffer to process
5130 * netif_receive_skb() is the main receive data processing function.
5131 * It always succeeds. The buffer may be dropped during processing
5132 * for congestion control or by the protocol layers.
5134 * This function may only be called from softirq context and interrupts
5135 * should be enabled.
5137 * Return values (usually ignored):
5138 * NET_RX_SUCCESS: no congestion
5139 * NET_RX_DROP: packet was dropped
5141 int netif_receive_skb(struct sk_buff *skb)
5143 trace_netif_receive_skb_entry(skb);
5145 return netif_receive_skb_internal(skb);
5147 EXPORT_SYMBOL(netif_receive_skb);
5150 * netif_receive_skb_list - process many receive buffers from network
5151 * @head: list of skbs to process.
5153 * Since return value of netif_receive_skb() is normally ignored, and
5154 * wouldn't be meaningful for a list, this function returns void.
5156 * This function may only be called from softirq context and interrupts
5157 * should be enabled.
5159 void netif_receive_skb_list(struct list_head *head)
5161 struct sk_buff *skb;
5163 if (list_empty(head))
5165 list_for_each_entry(skb, head, list)
5166 trace_netif_receive_skb_list_entry(skb);
5167 netif_receive_skb_list_internal(head);
5169 EXPORT_SYMBOL(netif_receive_skb_list);
5171 DEFINE_PER_CPU(struct work_struct, flush_works);
5173 /* Network device is going away, flush any packets still pending */
5174 static void flush_backlog(struct work_struct *work)
5176 struct sk_buff *skb, *tmp;
5177 struct softnet_data *sd;
5180 sd = this_cpu_ptr(&softnet_data);
5182 local_irq_disable();
5184 skb_queue_walk_safe(&sd->input_pkt_queue, skb, tmp) {
5185 if (skb->dev->reg_state == NETREG_UNREGISTERING) {
5186 __skb_unlink(skb, &sd->input_pkt_queue);
5188 input_queue_head_incr(sd);
5194 skb_queue_walk_safe(&sd->process_queue, skb, tmp) {
5195 if (skb->dev->reg_state == NETREG_UNREGISTERING) {
5196 __skb_unlink(skb, &sd->process_queue);
5198 input_queue_head_incr(sd);
5204 static void flush_all_backlogs(void)
5210 for_each_online_cpu(cpu)
5211 queue_work_on(cpu, system_highpri_wq,
5212 per_cpu_ptr(&flush_works, cpu));
5214 for_each_online_cpu(cpu)
5215 flush_work(per_cpu_ptr(&flush_works, cpu));
5220 static int napi_gro_complete(struct sk_buff *skb)
5222 struct packet_offload *ptype;
5223 __be16 type = skb->protocol;
5224 struct list_head *head = &offload_base;
5227 BUILD_BUG_ON(sizeof(struct napi_gro_cb) > sizeof(skb->cb));
5229 if (NAPI_GRO_CB(skb)->count == 1) {
5230 skb_shinfo(skb)->gso_size = 0;
5235 list_for_each_entry_rcu(ptype, head, list) {
5236 if (ptype->type != type || !ptype->callbacks.gro_complete)
5239 err = ptype->callbacks.gro_complete(skb, 0);
5245 WARN_ON(&ptype->list == head);
5247 return NET_RX_SUCCESS;
5251 return netif_receive_skb_internal(skb);
5254 static void __napi_gro_flush_chain(struct napi_struct *napi, u32 index,
5257 struct list_head *head = &napi->gro_hash[index].list;
5258 struct sk_buff *skb, *p;
5260 list_for_each_entry_safe_reverse(skb, p, head, list) {
5261 if (flush_old && NAPI_GRO_CB(skb)->age == jiffies)
5263 list_del_init(&skb->list);
5264 napi_gro_complete(skb);
5266 napi->gro_hash[index].count--;
5270 /* napi->gro_hash[].list contains packets ordered by age.
5271 * youngest packets at the head of it.
5272 * Complete skbs in reverse order to reduce latencies.
5274 void napi_gro_flush(struct napi_struct *napi, bool flush_old)
5278 for (i = 0; i < GRO_HASH_BUCKETS; i++)
5279 __napi_gro_flush_chain(napi, i, flush_old);
5281 EXPORT_SYMBOL(napi_gro_flush);
5283 static struct list_head *gro_list_prepare(struct napi_struct *napi,
5284 struct sk_buff *skb)
5286 unsigned int maclen = skb->dev->hard_header_len;
5287 u32 hash = skb_get_hash_raw(skb);
5288 struct list_head *head;
5291 head = &napi->gro_hash[hash & (GRO_HASH_BUCKETS - 1)].list;
5292 list_for_each_entry(p, head, list) {
5293 unsigned long diffs;
5295 NAPI_GRO_CB(p)->flush = 0;
5297 if (hash != skb_get_hash_raw(p)) {
5298 NAPI_GRO_CB(p)->same_flow = 0;
5302 diffs = (unsigned long)p->dev ^ (unsigned long)skb->dev;
5303 diffs |= p->vlan_tci ^ skb->vlan_tci;
5304 diffs |= skb_metadata_dst_cmp(p, skb);
5305 diffs |= skb_metadata_differs(p, skb);
5306 if (maclen == ETH_HLEN)
5307 diffs |= compare_ether_header(skb_mac_header(p),
5308 skb_mac_header(skb));
5310 diffs = memcmp(skb_mac_header(p),
5311 skb_mac_header(skb),
5313 NAPI_GRO_CB(p)->same_flow = !diffs;
5319 static void skb_gro_reset_offset(struct sk_buff *skb)
5321 const struct skb_shared_info *pinfo = skb_shinfo(skb);
5322 const skb_frag_t *frag0 = &pinfo->frags[0];
5324 NAPI_GRO_CB(skb)->data_offset = 0;
5325 NAPI_GRO_CB(skb)->frag0 = NULL;
5326 NAPI_GRO_CB(skb)->frag0_len = 0;
5328 if (skb_mac_header(skb) == skb_tail_pointer(skb) &&
5330 !PageHighMem(skb_frag_page(frag0))) {
5331 NAPI_GRO_CB(skb)->frag0 = skb_frag_address(frag0);
5332 NAPI_GRO_CB(skb)->frag0_len = min_t(unsigned int,
5333 skb_frag_size(frag0),
5334 skb->end - skb->tail);
5338 static void gro_pull_from_frag0(struct sk_buff *skb, int grow)
5340 struct skb_shared_info *pinfo = skb_shinfo(skb);
5342 BUG_ON(skb->end - skb->tail < grow);
5344 memcpy(skb_tail_pointer(skb), NAPI_GRO_CB(skb)->frag0, grow);
5346 skb->data_len -= grow;
5349 pinfo->frags[0].page_offset += grow;
5350 skb_frag_size_sub(&pinfo->frags[0], grow);
5352 if (unlikely(!skb_frag_size(&pinfo->frags[0]))) {
5353 skb_frag_unref(skb, 0);
5354 memmove(pinfo->frags, pinfo->frags + 1,
5355 --pinfo->nr_frags * sizeof(pinfo->frags[0]));
5359 static void gro_flush_oldest(struct list_head *head)
5361 struct sk_buff *oldest;
5363 oldest = list_last_entry(head, struct sk_buff, list);
5365 /* We are called with head length >= MAX_GRO_SKBS, so this is
5368 if (WARN_ON_ONCE(!oldest))
5371 /* Do not adjust napi->gro_count, caller is adding a new SKB to
5374 list_del(&oldest->list);
5375 napi_gro_complete(oldest);
5378 static enum gro_result dev_gro_receive(struct napi_struct *napi, struct sk_buff *skb)
5380 u32 hash = skb_get_hash_raw(skb) & (GRO_HASH_BUCKETS - 1);
5381 struct list_head *head = &offload_base;
5382 struct packet_offload *ptype;
5383 __be16 type = skb->protocol;
5384 struct list_head *gro_head;
5385 struct sk_buff *pp = NULL;
5386 enum gro_result ret;
5390 if (netif_elide_gro(skb->dev))
5393 gro_head = gro_list_prepare(napi, skb);
5396 list_for_each_entry_rcu(ptype, head, list) {
5397 if (ptype->type != type || !ptype->callbacks.gro_receive)
5400 skb_set_network_header(skb, skb_gro_offset(skb));
5401 skb_reset_mac_len(skb);
5402 NAPI_GRO_CB(skb)->same_flow = 0;
5403 NAPI_GRO_CB(skb)->flush = skb_is_gso(skb) || skb_has_frag_list(skb);
5404 NAPI_GRO_CB(skb)->free = 0;
5405 NAPI_GRO_CB(skb)->encap_mark = 0;
5406 NAPI_GRO_CB(skb)->recursion_counter = 0;
5407 NAPI_GRO_CB(skb)->is_fou = 0;
5408 NAPI_GRO_CB(skb)->is_atomic = 1;
5409 NAPI_GRO_CB(skb)->gro_remcsum_start = 0;
5411 /* Setup for GRO checksum validation */
5412 switch (skb->ip_summed) {
5413 case CHECKSUM_COMPLETE:
5414 NAPI_GRO_CB(skb)->csum = skb->csum;
5415 NAPI_GRO_CB(skb)->csum_valid = 1;
5416 NAPI_GRO_CB(skb)->csum_cnt = 0;
5418 case CHECKSUM_UNNECESSARY:
5419 NAPI_GRO_CB(skb)->csum_cnt = skb->csum_level + 1;
5420 NAPI_GRO_CB(skb)->csum_valid = 0;
5423 NAPI_GRO_CB(skb)->csum_cnt = 0;
5424 NAPI_GRO_CB(skb)->csum_valid = 0;
5427 pp = ptype->callbacks.gro_receive(gro_head, skb);
5432 if (&ptype->list == head)
5435 if (IS_ERR(pp) && PTR_ERR(pp) == -EINPROGRESS) {
5440 same_flow = NAPI_GRO_CB(skb)->same_flow;
5441 ret = NAPI_GRO_CB(skb)->free ? GRO_MERGED_FREE : GRO_MERGED;
5444 list_del_init(&pp->list);
5445 napi_gro_complete(pp);
5447 napi->gro_hash[hash].count--;
5453 if (NAPI_GRO_CB(skb)->flush)
5456 if (unlikely(napi->gro_hash[hash].count >= MAX_GRO_SKBS)) {
5457 gro_flush_oldest(gro_head);
5460 napi->gro_hash[hash].count++;
5462 NAPI_GRO_CB(skb)->count = 1;
5463 NAPI_GRO_CB(skb)->age = jiffies;
5464 NAPI_GRO_CB(skb)->last = skb;
5465 skb_shinfo(skb)->gso_size = skb_gro_len(skb);
5466 list_add(&skb->list, gro_head);
5470 grow = skb_gro_offset(skb) - skb_headlen(skb);
5472 gro_pull_from_frag0(skb, grow);
5481 struct packet_offload *gro_find_receive_by_type(__be16 type)
5483 struct list_head *offload_head = &offload_base;
5484 struct packet_offload *ptype;
5486 list_for_each_entry_rcu(ptype, offload_head, list) {
5487 if (ptype->type != type || !ptype->callbacks.gro_receive)
5493 EXPORT_SYMBOL(gro_find_receive_by_type);
5495 struct packet_offload *gro_find_complete_by_type(__be16 type)
5497 struct list_head *offload_head = &offload_base;
5498 struct packet_offload *ptype;
5500 list_for_each_entry_rcu(ptype, offload_head, list) {
5501 if (ptype->type != type || !ptype->callbacks.gro_complete)
5507 EXPORT_SYMBOL(gro_find_complete_by_type);
5509 static void napi_skb_free_stolen_head(struct sk_buff *skb)
5513 kmem_cache_free(skbuff_head_cache, skb);
5516 static gro_result_t napi_skb_finish(gro_result_t ret, struct sk_buff *skb)
5520 if (netif_receive_skb_internal(skb))
5528 case GRO_MERGED_FREE:
5529 if (NAPI_GRO_CB(skb)->free == NAPI_GRO_FREE_STOLEN_HEAD)
5530 napi_skb_free_stolen_head(skb);
5544 gro_result_t napi_gro_receive(struct napi_struct *napi, struct sk_buff *skb)
5546 skb_mark_napi_id(skb, napi);
5547 trace_napi_gro_receive_entry(skb);
5549 skb_gro_reset_offset(skb);
5551 return napi_skb_finish(dev_gro_receive(napi, skb), skb);
5553 EXPORT_SYMBOL(napi_gro_receive);
5555 static void napi_reuse_skb(struct napi_struct *napi, struct sk_buff *skb)
5557 if (unlikely(skb->pfmemalloc)) {
5561 __skb_pull(skb, skb_headlen(skb));
5562 /* restore the reserve we had after netdev_alloc_skb_ip_align() */
5563 skb_reserve(skb, NET_SKB_PAD + NET_IP_ALIGN - skb_headroom(skb));
5565 skb->dev = napi->dev;
5567 skb->encapsulation = 0;
5568 skb_shinfo(skb)->gso_type = 0;
5569 skb->truesize = SKB_TRUESIZE(skb_end_offset(skb));
5575 struct sk_buff *napi_get_frags(struct napi_struct *napi)
5577 struct sk_buff *skb = napi->skb;
5580 skb = napi_alloc_skb(napi, GRO_MAX_HEAD);
5583 skb_mark_napi_id(skb, napi);
5588 EXPORT_SYMBOL(napi_get_frags);
5590 static gro_result_t napi_frags_finish(struct napi_struct *napi,
5591 struct sk_buff *skb,
5597 __skb_push(skb, ETH_HLEN);
5598 skb->protocol = eth_type_trans(skb, skb->dev);
5599 if (ret == GRO_NORMAL && netif_receive_skb_internal(skb))
5604 napi_reuse_skb(napi, skb);
5607 case GRO_MERGED_FREE:
5608 if (NAPI_GRO_CB(skb)->free == NAPI_GRO_FREE_STOLEN_HEAD)
5609 napi_skb_free_stolen_head(skb);
5611 napi_reuse_skb(napi, skb);
5622 /* Upper GRO stack assumes network header starts at gro_offset=0
5623 * Drivers could call both napi_gro_frags() and napi_gro_receive()
5624 * We copy ethernet header into skb->data to have a common layout.
5626 static struct sk_buff *napi_frags_skb(struct napi_struct *napi)
5628 struct sk_buff *skb = napi->skb;
5629 const struct ethhdr *eth;
5630 unsigned int hlen = sizeof(*eth);
5634 skb_reset_mac_header(skb);
5635 skb_gro_reset_offset(skb);
5637 eth = skb_gro_header_fast(skb, 0);
5638 if (unlikely(skb_gro_header_hard(skb, hlen))) {
5639 eth = skb_gro_header_slow(skb, hlen, 0);
5640 if (unlikely(!eth)) {
5641 net_warn_ratelimited("%s: dropping impossible skb from %s\n",
5642 __func__, napi->dev->name);
5643 napi_reuse_skb(napi, skb);
5647 gro_pull_from_frag0(skb, hlen);
5648 NAPI_GRO_CB(skb)->frag0 += hlen;
5649 NAPI_GRO_CB(skb)->frag0_len -= hlen;
5651 __skb_pull(skb, hlen);
5654 * This works because the only protocols we care about don't require
5656 * We'll fix it up properly in napi_frags_finish()
5658 skb->protocol = eth->h_proto;
5663 gro_result_t napi_gro_frags(struct napi_struct *napi)
5665 struct sk_buff *skb = napi_frags_skb(napi);
5670 trace_napi_gro_frags_entry(skb);
5672 return napi_frags_finish(napi, skb, dev_gro_receive(napi, skb));
5674 EXPORT_SYMBOL(napi_gro_frags);
5676 /* Compute the checksum from gro_offset and return the folded value
5677 * after adding in any pseudo checksum.
5679 __sum16 __skb_gro_checksum_complete(struct sk_buff *skb)
5684 wsum = skb_checksum(skb, skb_gro_offset(skb), skb_gro_len(skb), 0);
5686 /* NAPI_GRO_CB(skb)->csum holds pseudo checksum */
5687 sum = csum_fold(csum_add(NAPI_GRO_CB(skb)->csum, wsum));
5689 if (unlikely(skb->ip_summed == CHECKSUM_COMPLETE) &&
5690 !skb->csum_complete_sw)
5691 netdev_rx_csum_fault(skb->dev);
5694 NAPI_GRO_CB(skb)->csum = wsum;
5695 NAPI_GRO_CB(skb)->csum_valid = 1;
5699 EXPORT_SYMBOL(__skb_gro_checksum_complete);
5701 static void net_rps_send_ipi(struct softnet_data *remsd)
5705 struct softnet_data *next = remsd->rps_ipi_next;
5707 if (cpu_online(remsd->cpu))
5708 smp_call_function_single_async(remsd->cpu, &remsd->csd);
5715 * net_rps_action_and_irq_enable sends any pending IPI's for rps.
5716 * Note: called with local irq disabled, but exits with local irq enabled.
5718 static void net_rps_action_and_irq_enable(struct softnet_data *sd)
5721 struct softnet_data *remsd = sd->rps_ipi_list;
5724 sd->rps_ipi_list = NULL;
5728 /* Send pending IPI's to kick RPS processing on remote cpus. */
5729 net_rps_send_ipi(remsd);
5735 static bool sd_has_rps_ipi_waiting(struct softnet_data *sd)
5738 return sd->rps_ipi_list != NULL;
5744 static int process_backlog(struct napi_struct *napi, int quota)
5746 struct softnet_data *sd = container_of(napi, struct softnet_data, backlog);
5750 /* Check if we have pending ipi, its better to send them now,
5751 * not waiting net_rx_action() end.
5753 if (sd_has_rps_ipi_waiting(sd)) {
5754 local_irq_disable();
5755 net_rps_action_and_irq_enable(sd);
5758 napi->weight = dev_rx_weight;
5760 struct sk_buff *skb;
5762 while ((skb = __skb_dequeue(&sd->process_queue))) {
5764 __netif_receive_skb(skb);
5766 input_queue_head_incr(sd);
5767 if (++work >= quota)
5772 local_irq_disable();
5774 if (skb_queue_empty(&sd->input_pkt_queue)) {
5776 * Inline a custom version of __napi_complete().
5777 * only current cpu owns and manipulates this napi,
5778 * and NAPI_STATE_SCHED is the only possible flag set
5780 * We can use a plain write instead of clear_bit(),
5781 * and we dont need an smp_mb() memory barrier.
5786 skb_queue_splice_tail_init(&sd->input_pkt_queue,
5787 &sd->process_queue);
5797 * __napi_schedule - schedule for receive
5798 * @n: entry to schedule
5800 * The entry's receive function will be scheduled to run.
5801 * Consider using __napi_schedule_irqoff() if hard irqs are masked.
5803 void __napi_schedule(struct napi_struct *n)
5805 unsigned long flags;
5807 local_irq_save(flags);
5808 ____napi_schedule(this_cpu_ptr(&softnet_data), n);
5809 local_irq_restore(flags);
5811 EXPORT_SYMBOL(__napi_schedule);
5814 * napi_schedule_prep - check if napi can be scheduled
5817 * Test if NAPI routine is already running, and if not mark
5818 * it as running. This is used as a condition variable
5819 * insure only one NAPI poll instance runs. We also make
5820 * sure there is no pending NAPI disable.
5822 bool napi_schedule_prep(struct napi_struct *n)
5824 unsigned long val, new;
5827 val = READ_ONCE(n->state);
5828 if (unlikely(val & NAPIF_STATE_DISABLE))
5830 new = val | NAPIF_STATE_SCHED;
5832 /* Sets STATE_MISSED bit if STATE_SCHED was already set
5833 * This was suggested by Alexander Duyck, as compiler
5834 * emits better code than :
5835 * if (val & NAPIF_STATE_SCHED)
5836 * new |= NAPIF_STATE_MISSED;
5838 new |= (val & NAPIF_STATE_SCHED) / NAPIF_STATE_SCHED *
5840 } while (cmpxchg(&n->state, val, new) != val);
5842 return !(val & NAPIF_STATE_SCHED);
5844 EXPORT_SYMBOL(napi_schedule_prep);
5847 * __napi_schedule_irqoff - schedule for receive
5848 * @n: entry to schedule
5850 * Variant of __napi_schedule() assuming hard irqs are masked
5852 void __napi_schedule_irqoff(struct napi_struct *n)
5854 ____napi_schedule(this_cpu_ptr(&softnet_data), n);
5856 EXPORT_SYMBOL(__napi_schedule_irqoff);
5858 bool napi_complete_done(struct napi_struct *n, int work_done)
5860 unsigned long flags, val, new;
5863 * 1) Don't let napi dequeue from the cpu poll list
5864 * just in case its running on a different cpu.
5865 * 2) If we are busy polling, do nothing here, we have
5866 * the guarantee we will be called later.
5868 if (unlikely(n->state & (NAPIF_STATE_NPSVC |
5869 NAPIF_STATE_IN_BUSY_POLL)))
5873 unsigned long timeout = 0;
5876 timeout = n->dev->gro_flush_timeout;
5879 hrtimer_start(&n->timer, ns_to_ktime(timeout),
5880 HRTIMER_MODE_REL_PINNED);
5882 napi_gro_flush(n, false);
5884 if (unlikely(!list_empty(&n->poll_list))) {
5885 /* If n->poll_list is not empty, we need to mask irqs */
5886 local_irq_save(flags);
5887 list_del_init(&n->poll_list);
5888 local_irq_restore(flags);
5892 val = READ_ONCE(n->state);
5894 WARN_ON_ONCE(!(val & NAPIF_STATE_SCHED));
5896 new = val & ~(NAPIF_STATE_MISSED | NAPIF_STATE_SCHED);
5898 /* If STATE_MISSED was set, leave STATE_SCHED set,
5899 * because we will call napi->poll() one more time.
5900 * This C code was suggested by Alexander Duyck to help gcc.
5902 new |= (val & NAPIF_STATE_MISSED) / NAPIF_STATE_MISSED *
5904 } while (cmpxchg(&n->state, val, new) != val);
5906 if (unlikely(val & NAPIF_STATE_MISSED)) {
5913 EXPORT_SYMBOL(napi_complete_done);
5915 /* must be called under rcu_read_lock(), as we dont take a reference */
5916 static struct napi_struct *napi_by_id(unsigned int napi_id)
5918 unsigned int hash = napi_id % HASH_SIZE(napi_hash);
5919 struct napi_struct *napi;
5921 hlist_for_each_entry_rcu(napi, &napi_hash[hash], napi_hash_node)
5922 if (napi->napi_id == napi_id)
5928 #if defined(CONFIG_NET_RX_BUSY_POLL)
5930 #define BUSY_POLL_BUDGET 8
5932 static void busy_poll_stop(struct napi_struct *napi, void *have_poll_lock)
5936 /* Busy polling means there is a high chance device driver hard irq
5937 * could not grab NAPI_STATE_SCHED, and that NAPI_STATE_MISSED was
5938 * set in napi_schedule_prep().
5939 * Since we are about to call napi->poll() once more, we can safely
5940 * clear NAPI_STATE_MISSED.
5942 * Note: x86 could use a single "lock and ..." instruction
5943 * to perform these two clear_bit()
5945 clear_bit(NAPI_STATE_MISSED, &napi->state);
5946 clear_bit(NAPI_STATE_IN_BUSY_POLL, &napi->state);
5950 /* All we really want here is to re-enable device interrupts.
5951 * Ideally, a new ndo_busy_poll_stop() could avoid another round.
5953 rc = napi->poll(napi, BUSY_POLL_BUDGET);
5954 trace_napi_poll(napi, rc, BUSY_POLL_BUDGET);
5955 netpoll_poll_unlock(have_poll_lock);
5956 if (rc == BUSY_POLL_BUDGET)
5957 __napi_schedule(napi);
5961 void napi_busy_loop(unsigned int napi_id,
5962 bool (*loop_end)(void *, unsigned long),
5965 unsigned long start_time = loop_end ? busy_loop_current_time() : 0;
5966 int (*napi_poll)(struct napi_struct *napi, int budget);
5967 void *have_poll_lock = NULL;
5968 struct napi_struct *napi;
5975 napi = napi_by_id(napi_id);
5985 unsigned long val = READ_ONCE(napi->state);
5987 /* If multiple threads are competing for this napi,
5988 * we avoid dirtying napi->state as much as we can.
5990 if (val & (NAPIF_STATE_DISABLE | NAPIF_STATE_SCHED |
5991 NAPIF_STATE_IN_BUSY_POLL))
5993 if (cmpxchg(&napi->state, val,
5994 val | NAPIF_STATE_IN_BUSY_POLL |
5995 NAPIF_STATE_SCHED) != val)
5997 have_poll_lock = netpoll_poll_lock(napi);
5998 napi_poll = napi->poll;
6000 work = napi_poll(napi, BUSY_POLL_BUDGET);
6001 trace_napi_poll(napi, work, BUSY_POLL_BUDGET);
6004 __NET_ADD_STATS(dev_net(napi->dev),
6005 LINUX_MIB_BUSYPOLLRXPACKETS, work);
6008 if (!loop_end || loop_end(loop_end_arg, start_time))
6011 if (unlikely(need_resched())) {
6013 busy_poll_stop(napi, have_poll_lock);
6017 if (loop_end(loop_end_arg, start_time))
6024 busy_poll_stop(napi, have_poll_lock);
6029 EXPORT_SYMBOL(napi_busy_loop);
6031 #endif /* CONFIG_NET_RX_BUSY_POLL */
6033 static void napi_hash_add(struct napi_struct *napi)
6035 if (test_bit(NAPI_STATE_NO_BUSY_POLL, &napi->state) ||
6036 test_and_set_bit(NAPI_STATE_HASHED, &napi->state))
6039 spin_lock(&napi_hash_lock);
6041 /* 0..NR_CPUS range is reserved for sender_cpu use */
6043 if (unlikely(++napi_gen_id < MIN_NAPI_ID))
6044 napi_gen_id = MIN_NAPI_ID;
6045 } while (napi_by_id(napi_gen_id));
6046 napi->napi_id = napi_gen_id;
6048 hlist_add_head_rcu(&napi->napi_hash_node,
6049 &napi_hash[napi->napi_id % HASH_SIZE(napi_hash)]);
6051 spin_unlock(&napi_hash_lock);
6054 /* Warning : caller is responsible to make sure rcu grace period
6055 * is respected before freeing memory containing @napi
6057 bool napi_hash_del(struct napi_struct *napi)
6059 bool rcu_sync_needed = false;
6061 spin_lock(&napi_hash_lock);
6063 if (test_and_clear_bit(NAPI_STATE_HASHED, &napi->state)) {
6064 rcu_sync_needed = true;
6065 hlist_del_rcu(&napi->napi_hash_node);
6067 spin_unlock(&napi_hash_lock);
6068 return rcu_sync_needed;
6070 EXPORT_SYMBOL_GPL(napi_hash_del);
6072 static enum hrtimer_restart napi_watchdog(struct hrtimer *timer)
6074 struct napi_struct *napi;
6076 napi = container_of(timer, struct napi_struct, timer);
6078 /* Note : we use a relaxed variant of napi_schedule_prep() not setting
6079 * NAPI_STATE_MISSED, since we do not react to a device IRQ.
6081 if (napi->gro_count && !napi_disable_pending(napi) &&
6082 !test_and_set_bit(NAPI_STATE_SCHED, &napi->state))
6083 __napi_schedule_irqoff(napi);
6085 return HRTIMER_NORESTART;
6088 void netif_napi_add(struct net_device *dev, struct napi_struct *napi,
6089 int (*poll)(struct napi_struct *, int), int weight)
6093 INIT_LIST_HEAD(&napi->poll_list);
6094 hrtimer_init(&napi->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_PINNED);
6095 napi->timer.function = napi_watchdog;
6096 napi->gro_count = 0;
6097 for (i = 0; i < GRO_HASH_BUCKETS; i++) {
6098 INIT_LIST_HEAD(&napi->gro_hash[i].list);
6099 napi->gro_hash[i].count = 0;
6103 if (weight > NAPI_POLL_WEIGHT)
6104 pr_err_once("netif_napi_add() called with weight %d on device %s\n",
6106 napi->weight = weight;
6107 list_add(&napi->dev_list, &dev->napi_list);
6109 #ifdef CONFIG_NETPOLL
6110 napi->poll_owner = -1;
6112 set_bit(NAPI_STATE_SCHED, &napi->state);
6113 napi_hash_add(napi);
6115 EXPORT_SYMBOL(netif_napi_add);
6117 void napi_disable(struct napi_struct *n)
6120 set_bit(NAPI_STATE_DISABLE, &n->state);
6122 while (test_and_set_bit(NAPI_STATE_SCHED, &n->state))
6124 while (test_and_set_bit(NAPI_STATE_NPSVC, &n->state))
6127 hrtimer_cancel(&n->timer);
6129 clear_bit(NAPI_STATE_DISABLE, &n->state);
6131 EXPORT_SYMBOL(napi_disable);
6133 static void flush_gro_hash(struct napi_struct *napi)
6137 for (i = 0; i < GRO_HASH_BUCKETS; i++) {
6138 struct sk_buff *skb, *n;
6140 list_for_each_entry_safe(skb, n, &napi->gro_hash[i].list, list)
6142 napi->gro_hash[i].count = 0;
6146 /* Must be called in process context */
6147 void netif_napi_del(struct napi_struct *napi)
6150 if (napi_hash_del(napi))
6152 list_del_init(&napi->dev_list);
6153 napi_free_frags(napi);
6155 flush_gro_hash(napi);
6156 napi->gro_count = 0;
6158 EXPORT_SYMBOL(netif_napi_del);
6160 static int napi_poll(struct napi_struct *n, struct list_head *repoll)
6165 list_del_init(&n->poll_list);
6167 have = netpoll_poll_lock(n);
6171 /* This NAPI_STATE_SCHED test is for avoiding a race
6172 * with netpoll's poll_napi(). Only the entity which
6173 * obtains the lock and sees NAPI_STATE_SCHED set will
6174 * actually make the ->poll() call. Therefore we avoid
6175 * accidentally calling ->poll() when NAPI is not scheduled.
6178 if (test_bit(NAPI_STATE_SCHED, &n->state)) {
6179 work = n->poll(n, weight);
6180 trace_napi_poll(n, work, weight);
6183 WARN_ON_ONCE(work > weight);
6185 if (likely(work < weight))
6188 /* Drivers must not modify the NAPI state if they
6189 * consume the entire weight. In such cases this code
6190 * still "owns" the NAPI instance and therefore can
6191 * move the instance around on the list at-will.
6193 if (unlikely(napi_disable_pending(n))) {
6199 /* flush too old packets
6200 * If HZ < 1000, flush all packets.
6202 napi_gro_flush(n, HZ >= 1000);
6205 /* Some drivers may have called napi_schedule
6206 * prior to exhausting their budget.
6208 if (unlikely(!list_empty(&n->poll_list))) {
6209 pr_warn_once("%s: Budget exhausted after napi rescheduled\n",
6210 n->dev ? n->dev->name : "backlog");
6214 list_add_tail(&n->poll_list, repoll);
6217 netpoll_poll_unlock(have);
6222 static __latent_entropy void net_rx_action(struct softirq_action *h)
6224 struct softnet_data *sd = this_cpu_ptr(&softnet_data);
6225 unsigned long time_limit = jiffies +
6226 usecs_to_jiffies(netdev_budget_usecs);
6227 int budget = netdev_budget;
6231 local_irq_disable();
6232 list_splice_init(&sd->poll_list, &list);
6236 struct napi_struct *n;
6238 if (list_empty(&list)) {
6239 if (!sd_has_rps_ipi_waiting(sd) && list_empty(&repoll))
6244 n = list_first_entry(&list, struct napi_struct, poll_list);
6245 budget -= napi_poll(n, &repoll);
6247 /* If softirq window is exhausted then punt.
6248 * Allow this to run for 2 jiffies since which will allow
6249 * an average latency of 1.5/HZ.
6251 if (unlikely(budget <= 0 ||
6252 time_after_eq(jiffies, time_limit))) {
6258 local_irq_disable();
6260 list_splice_tail_init(&sd->poll_list, &list);
6261 list_splice_tail(&repoll, &list);
6262 list_splice(&list, &sd->poll_list);
6263 if (!list_empty(&sd->poll_list))
6264 __raise_softirq_irqoff(NET_RX_SOFTIRQ);
6266 net_rps_action_and_irq_enable(sd);
6268 __kfree_skb_flush();
6271 struct netdev_adjacent {
6272 struct net_device *dev;
6274 /* upper master flag, there can only be one master device per list */
6277 /* counter for the number of times this device was added to us */
6280 /* private field for the users */
6283 struct list_head list;
6284 struct rcu_head rcu;
6287 static struct netdev_adjacent *__netdev_find_adj(struct net_device *adj_dev,
6288 struct list_head *adj_list)
6290 struct netdev_adjacent *adj;
6292 list_for_each_entry(adj, adj_list, list) {
6293 if (adj->dev == adj_dev)
6299 static int __netdev_has_upper_dev(struct net_device *upper_dev, void *data)
6301 struct net_device *dev = data;
6303 return upper_dev == dev;
6307 * netdev_has_upper_dev - Check if device is linked to an upper device
6309 * @upper_dev: upper device to check
6311 * Find out if a device is linked to specified upper device and return true
6312 * in case it is. Note that this checks only immediate upper device,
6313 * not through a complete stack of devices. The caller must hold the RTNL lock.
6315 bool netdev_has_upper_dev(struct net_device *dev,
6316 struct net_device *upper_dev)
6320 return netdev_walk_all_upper_dev_rcu(dev, __netdev_has_upper_dev,
6323 EXPORT_SYMBOL(netdev_has_upper_dev);
6326 * netdev_has_upper_dev_all - Check if device is linked to an upper device
6328 * @upper_dev: upper device to check
6330 * Find out if a device is linked to specified upper device and return true
6331 * in case it is. Note that this checks the entire upper device chain.
6332 * The caller must hold rcu lock.
6335 bool netdev_has_upper_dev_all_rcu(struct net_device *dev,
6336 struct net_device *upper_dev)
6338 return !!netdev_walk_all_upper_dev_rcu(dev, __netdev_has_upper_dev,
6341 EXPORT_SYMBOL(netdev_has_upper_dev_all_rcu);
6344 * netdev_has_any_upper_dev - Check if device is linked to some device
6347 * Find out if a device is linked to an upper device and return true in case
6348 * it is. The caller must hold the RTNL lock.
6350 bool netdev_has_any_upper_dev(struct net_device *dev)
6354 return !list_empty(&dev->adj_list.upper);
6356 EXPORT_SYMBOL(netdev_has_any_upper_dev);
6359 * netdev_master_upper_dev_get - Get master upper device
6362 * Find a master upper device and return pointer to it or NULL in case
6363 * it's not there. The caller must hold the RTNL lock.
6365 struct net_device *netdev_master_upper_dev_get(struct net_device *dev)
6367 struct netdev_adjacent *upper;
6371 if (list_empty(&dev->adj_list.upper))
6374 upper = list_first_entry(&dev->adj_list.upper,
6375 struct netdev_adjacent, list);
6376 if (likely(upper->master))
6380 EXPORT_SYMBOL(netdev_master_upper_dev_get);
6383 * netdev_has_any_lower_dev - Check if device is linked to some device
6386 * Find out if a device is linked to a lower device and return true in case
6387 * it is. The caller must hold the RTNL lock.
6389 static bool netdev_has_any_lower_dev(struct net_device *dev)
6393 return !list_empty(&dev->adj_list.lower);
6396 void *netdev_adjacent_get_private(struct list_head *adj_list)
6398 struct netdev_adjacent *adj;
6400 adj = list_entry(adj_list, struct netdev_adjacent, list);
6402 return adj->private;
6404 EXPORT_SYMBOL(netdev_adjacent_get_private);
6407 * netdev_upper_get_next_dev_rcu - Get the next dev from upper list
6409 * @iter: list_head ** of the current position
6411 * Gets the next device from the dev's upper list, starting from iter
6412 * position. The caller must hold RCU read lock.
6414 struct net_device *netdev_upper_get_next_dev_rcu(struct net_device *dev,
6415 struct list_head **iter)
6417 struct netdev_adjacent *upper;
6419 WARN_ON_ONCE(!rcu_read_lock_held() && !lockdep_rtnl_is_held());
6421 upper = list_entry_rcu((*iter)->next, struct netdev_adjacent, list);
6423 if (&upper->list == &dev->adj_list.upper)
6426 *iter = &upper->list;
6430 EXPORT_SYMBOL(netdev_upper_get_next_dev_rcu);
6432 static struct net_device *netdev_next_upper_dev_rcu(struct net_device *dev,
6433 struct list_head **iter)
6435 struct netdev_adjacent *upper;
6437 WARN_ON_ONCE(!rcu_read_lock_held() && !lockdep_rtnl_is_held());
6439 upper = list_entry_rcu((*iter)->next, struct netdev_adjacent, list);
6441 if (&upper->list == &dev->adj_list.upper)
6444 *iter = &upper->list;
6449 int netdev_walk_all_upper_dev_rcu(struct net_device *dev,
6450 int (*fn)(struct net_device *dev,
6454 struct net_device *udev;
6455 struct list_head *iter;
6458 for (iter = &dev->adj_list.upper,
6459 udev = netdev_next_upper_dev_rcu(dev, &iter);
6461 udev = netdev_next_upper_dev_rcu(dev, &iter)) {
6462 /* first is the upper device itself */
6463 ret = fn(udev, data);
6467 /* then look at all of its upper devices */
6468 ret = netdev_walk_all_upper_dev_rcu(udev, fn, data);
6475 EXPORT_SYMBOL_GPL(netdev_walk_all_upper_dev_rcu);
6478 * netdev_lower_get_next_private - Get the next ->private from the
6479 * lower neighbour list
6481 * @iter: list_head ** of the current position
6483 * Gets the next netdev_adjacent->private from the dev's lower neighbour
6484 * list, starting from iter position. The caller must hold either hold the
6485 * RTNL lock or its own locking that guarantees that the neighbour lower
6486 * list will remain unchanged.
6488 void *netdev_lower_get_next_private(struct net_device *dev,
6489 struct list_head **iter)
6491 struct netdev_adjacent *lower;
6493 lower = list_entry(*iter, struct netdev_adjacent, list);
6495 if (&lower->list == &dev->adj_list.lower)
6498 *iter = lower->list.next;
6500 return lower->private;
6502 EXPORT_SYMBOL(netdev_lower_get_next_private);
6505 * netdev_lower_get_next_private_rcu - Get the next ->private from the
6506 * lower neighbour list, RCU
6509 * @iter: list_head ** of the current position
6511 * Gets the next netdev_adjacent->private from the dev's lower neighbour
6512 * list, starting from iter position. The caller must hold RCU read lock.
6514 void *netdev_lower_get_next_private_rcu(struct net_device *dev,
6515 struct list_head **iter)
6517 struct netdev_adjacent *lower;
6519 WARN_ON_ONCE(!rcu_read_lock_held());
6521 lower = list_entry_rcu((*iter)->next, struct netdev_adjacent, list);
6523 if (&lower->list == &dev->adj_list.lower)
6526 *iter = &lower->list;
6528 return lower->private;
6530 EXPORT_SYMBOL(netdev_lower_get_next_private_rcu);
6533 * netdev_lower_get_next - Get the next device from the lower neighbour
6536 * @iter: list_head ** of the current position
6538 * Gets the next netdev_adjacent from the dev's lower neighbour
6539 * list, starting from iter position. The caller must hold RTNL lock or
6540 * its own locking that guarantees that the neighbour lower
6541 * list will remain unchanged.
6543 void *netdev_lower_get_next(struct net_device *dev, struct list_head **iter)
6545 struct netdev_adjacent *lower;
6547 lower = list_entry(*iter, struct netdev_adjacent, list);
6549 if (&lower->list == &dev->adj_list.lower)
6552 *iter = lower->list.next;
6556 EXPORT_SYMBOL(netdev_lower_get_next);
6558 static struct net_device *netdev_next_lower_dev(struct net_device *dev,
6559 struct list_head **iter)
6561 struct netdev_adjacent *lower;
6563 lower = list_entry((*iter)->next, struct netdev_adjacent, list);
6565 if (&lower->list == &dev->adj_list.lower)
6568 *iter = &lower->list;
6573 int netdev_walk_all_lower_dev(struct net_device *dev,
6574 int (*fn)(struct net_device *dev,
6578 struct net_device *ldev;
6579 struct list_head *iter;
6582 for (iter = &dev->adj_list.lower,
6583 ldev = netdev_next_lower_dev(dev, &iter);
6585 ldev = netdev_next_lower_dev(dev, &iter)) {
6586 /* first is the lower device itself */
6587 ret = fn(ldev, data);
6591 /* then look at all of its lower devices */
6592 ret = netdev_walk_all_lower_dev(ldev, fn, data);
6599 EXPORT_SYMBOL_GPL(netdev_walk_all_lower_dev);
6601 static struct net_device *netdev_next_lower_dev_rcu(struct net_device *dev,
6602 struct list_head **iter)
6604 struct netdev_adjacent *lower;
6606 lower = list_entry_rcu((*iter)->next, struct netdev_adjacent, list);
6607 if (&lower->list == &dev->adj_list.lower)
6610 *iter = &lower->list;
6615 int netdev_walk_all_lower_dev_rcu(struct net_device *dev,
6616 int (*fn)(struct net_device *dev,
6620 struct net_device *ldev;
6621 struct list_head *iter;
6624 for (iter = &dev->adj_list.lower,
6625 ldev = netdev_next_lower_dev_rcu(dev, &iter);
6627 ldev = netdev_next_lower_dev_rcu(dev, &iter)) {
6628 /* first is the lower device itself */
6629 ret = fn(ldev, data);
6633 /* then look at all of its lower devices */
6634 ret = netdev_walk_all_lower_dev_rcu(ldev, fn, data);
6641 EXPORT_SYMBOL_GPL(netdev_walk_all_lower_dev_rcu);
6644 * netdev_lower_get_first_private_rcu - Get the first ->private from the
6645 * lower neighbour list, RCU
6649 * Gets the first netdev_adjacent->private from the dev's lower neighbour
6650 * list. The caller must hold RCU read lock.
6652 void *netdev_lower_get_first_private_rcu(struct net_device *dev)
6654 struct netdev_adjacent *lower;
6656 lower = list_first_or_null_rcu(&dev->adj_list.lower,
6657 struct netdev_adjacent, list);
6659 return lower->private;
6662 EXPORT_SYMBOL(netdev_lower_get_first_private_rcu);
6665 * netdev_master_upper_dev_get_rcu - Get master upper device
6668 * Find a master upper device and return pointer to it or NULL in case
6669 * it's not there. The caller must hold the RCU read lock.
6671 struct net_device *netdev_master_upper_dev_get_rcu(struct net_device *dev)
6673 struct netdev_adjacent *upper;
6675 upper = list_first_or_null_rcu(&dev->adj_list.upper,
6676 struct netdev_adjacent, list);
6677 if (upper && likely(upper->master))
6681 EXPORT_SYMBOL(netdev_master_upper_dev_get_rcu);
6683 static int netdev_adjacent_sysfs_add(struct net_device *dev,
6684 struct net_device *adj_dev,
6685 struct list_head *dev_list)
6687 char linkname[IFNAMSIZ+7];
6689 sprintf(linkname, dev_list == &dev->adj_list.upper ?
6690 "upper_%s" : "lower_%s", adj_dev->name);
6691 return sysfs_create_link(&(dev->dev.kobj), &(adj_dev->dev.kobj),
6694 static void netdev_adjacent_sysfs_del(struct net_device *dev,
6696 struct list_head *dev_list)
6698 char linkname[IFNAMSIZ+7];
6700 sprintf(linkname, dev_list == &dev->adj_list.upper ?
6701 "upper_%s" : "lower_%s", name);
6702 sysfs_remove_link(&(dev->dev.kobj), linkname);
6705 static inline bool netdev_adjacent_is_neigh_list(struct net_device *dev,
6706 struct net_device *adj_dev,
6707 struct list_head *dev_list)
6709 return (dev_list == &dev->adj_list.upper ||
6710 dev_list == &dev->adj_list.lower) &&
6711 net_eq(dev_net(dev), dev_net(adj_dev));
6714 static int __netdev_adjacent_dev_insert(struct net_device *dev,
6715 struct net_device *adj_dev,
6716 struct list_head *dev_list,
6717 void *private, bool master)
6719 struct netdev_adjacent *adj;
6722 adj = __netdev_find_adj(adj_dev, dev_list);
6726 pr_debug("Insert adjacency: dev %s adj_dev %s adj->ref_nr %d\n",
6727 dev->name, adj_dev->name, adj->ref_nr);
6732 adj = kmalloc(sizeof(*adj), GFP_KERNEL);
6737 adj->master = master;
6739 adj->private = private;
6742 pr_debug("Insert adjacency: dev %s adj_dev %s adj->ref_nr %d; dev_hold on %s\n",
6743 dev->name, adj_dev->name, adj->ref_nr, adj_dev->name);
6745 if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list)) {
6746 ret = netdev_adjacent_sysfs_add(dev, adj_dev, dev_list);
6751 /* Ensure that master link is always the first item in list. */
6753 ret = sysfs_create_link(&(dev->dev.kobj),
6754 &(adj_dev->dev.kobj), "master");
6756 goto remove_symlinks;
6758 list_add_rcu(&adj->list, dev_list);
6760 list_add_tail_rcu(&adj->list, dev_list);
6766 if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list))
6767 netdev_adjacent_sysfs_del(dev, adj_dev->name, dev_list);
6775 static void __netdev_adjacent_dev_remove(struct net_device *dev,
6776 struct net_device *adj_dev,
6778 struct list_head *dev_list)
6780 struct netdev_adjacent *adj;
6782 pr_debug("Remove adjacency: dev %s adj_dev %s ref_nr %d\n",
6783 dev->name, adj_dev->name, ref_nr);
6785 adj = __netdev_find_adj(adj_dev, dev_list);
6788 pr_err("Adjacency does not exist for device %s from %s\n",
6789 dev->name, adj_dev->name);
6794 if (adj->ref_nr > ref_nr) {
6795 pr_debug("adjacency: %s to %s ref_nr - %d = %d\n",
6796 dev->name, adj_dev->name, ref_nr,
6797 adj->ref_nr - ref_nr);
6798 adj->ref_nr -= ref_nr;
6803 sysfs_remove_link(&(dev->dev.kobj), "master");
6805 if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list))
6806 netdev_adjacent_sysfs_del(dev, adj_dev->name, dev_list);
6808 list_del_rcu(&adj->list);
6809 pr_debug("adjacency: dev_put for %s, because link removed from %s to %s\n",
6810 adj_dev->name, dev->name, adj_dev->name);
6812 kfree_rcu(adj, rcu);
6815 static int __netdev_adjacent_dev_link_lists(struct net_device *dev,
6816 struct net_device *upper_dev,
6817 struct list_head *up_list,
6818 struct list_head *down_list,
6819 void *private, bool master)
6823 ret = __netdev_adjacent_dev_insert(dev, upper_dev, up_list,
6828 ret = __netdev_adjacent_dev_insert(upper_dev, dev, down_list,
6831 __netdev_adjacent_dev_remove(dev, upper_dev, 1, up_list);
6838 static void __netdev_adjacent_dev_unlink_lists(struct net_device *dev,
6839 struct net_device *upper_dev,
6841 struct list_head *up_list,
6842 struct list_head *down_list)
6844 __netdev_adjacent_dev_remove(dev, upper_dev, ref_nr, up_list);
6845 __netdev_adjacent_dev_remove(upper_dev, dev, ref_nr, down_list);
6848 static int __netdev_adjacent_dev_link_neighbour(struct net_device *dev,
6849 struct net_device *upper_dev,
6850 void *private, bool master)
6852 return __netdev_adjacent_dev_link_lists(dev, upper_dev,
6853 &dev->adj_list.upper,
6854 &upper_dev->adj_list.lower,
6858 static void __netdev_adjacent_dev_unlink_neighbour(struct net_device *dev,
6859 struct net_device *upper_dev)
6861 __netdev_adjacent_dev_unlink_lists(dev, upper_dev, 1,
6862 &dev->adj_list.upper,
6863 &upper_dev->adj_list.lower);
6866 static int __netdev_upper_dev_link(struct net_device *dev,
6867 struct net_device *upper_dev, bool master,
6868 void *upper_priv, void *upper_info,
6869 struct netlink_ext_ack *extack)
6871 struct netdev_notifier_changeupper_info changeupper_info = {
6876 .upper_dev = upper_dev,
6879 .upper_info = upper_info,
6881 struct net_device *master_dev;
6886 if (dev == upper_dev)
6889 /* To prevent loops, check if dev is not upper device to upper_dev. */
6890 if (netdev_has_upper_dev(upper_dev, dev))
6894 if (netdev_has_upper_dev(dev, upper_dev))
6897 master_dev = netdev_master_upper_dev_get(dev);
6899 return master_dev == upper_dev ? -EEXIST : -EBUSY;
6902 ret = call_netdevice_notifiers_info(NETDEV_PRECHANGEUPPER,
6903 &changeupper_info.info);
6904 ret = notifier_to_errno(ret);
6908 ret = __netdev_adjacent_dev_link_neighbour(dev, upper_dev, upper_priv,
6913 ret = call_netdevice_notifiers_info(NETDEV_CHANGEUPPER,
6914 &changeupper_info.info);
6915 ret = notifier_to_errno(ret);
6922 __netdev_adjacent_dev_unlink_neighbour(dev, upper_dev);
6928 * netdev_upper_dev_link - Add a link to the upper device
6930 * @upper_dev: new upper device
6931 * @extack: netlink extended ack
6933 * Adds a link to device which is upper to this one. The caller must hold
6934 * the RTNL lock. On a failure a negative errno code is returned.
6935 * On success the reference counts are adjusted and the function
6938 int netdev_upper_dev_link(struct net_device *dev,
6939 struct net_device *upper_dev,
6940 struct netlink_ext_ack *extack)
6942 return __netdev_upper_dev_link(dev, upper_dev, false,
6943 NULL, NULL, extack);
6945 EXPORT_SYMBOL(netdev_upper_dev_link);
6948 * netdev_master_upper_dev_link - Add a master link to the upper device
6950 * @upper_dev: new upper device
6951 * @upper_priv: upper device private
6952 * @upper_info: upper info to be passed down via notifier
6953 * @extack: netlink extended ack
6955 * Adds a link to device which is upper to this one. In this case, only
6956 * one master upper device can be linked, although other non-master devices
6957 * might be linked as well. The caller must hold the RTNL lock.
6958 * On a failure a negative errno code is returned. On success the reference
6959 * counts are adjusted and the function returns zero.
6961 int netdev_master_upper_dev_link(struct net_device *dev,
6962 struct net_device *upper_dev,
6963 void *upper_priv, void *upper_info,
6964 struct netlink_ext_ack *extack)
6966 return __netdev_upper_dev_link(dev, upper_dev, true,
6967 upper_priv, upper_info, extack);
6969 EXPORT_SYMBOL(netdev_master_upper_dev_link);
6972 * netdev_upper_dev_unlink - Removes a link to upper device
6974 * @upper_dev: new upper device
6976 * Removes a link to device which is upper to this one. The caller must hold
6979 void netdev_upper_dev_unlink(struct net_device *dev,
6980 struct net_device *upper_dev)
6982 struct netdev_notifier_changeupper_info changeupper_info = {
6986 .upper_dev = upper_dev,
6992 changeupper_info.master = netdev_master_upper_dev_get(dev) == upper_dev;
6994 call_netdevice_notifiers_info(NETDEV_PRECHANGEUPPER,
6995 &changeupper_info.info);
6997 __netdev_adjacent_dev_unlink_neighbour(dev, upper_dev);
6999 call_netdevice_notifiers_info(NETDEV_CHANGEUPPER,
7000 &changeupper_info.info);
7002 EXPORT_SYMBOL(netdev_upper_dev_unlink);
7005 * netdev_bonding_info_change - Dispatch event about slave change
7007 * @bonding_info: info to dispatch
7009 * Send NETDEV_BONDING_INFO to netdev notifiers with info.
7010 * The caller must hold the RTNL lock.
7012 void netdev_bonding_info_change(struct net_device *dev,
7013 struct netdev_bonding_info *bonding_info)
7015 struct netdev_notifier_bonding_info info = {
7019 memcpy(&info.bonding_info, bonding_info,
7020 sizeof(struct netdev_bonding_info));
7021 call_netdevice_notifiers_info(NETDEV_BONDING_INFO,
7024 EXPORT_SYMBOL(netdev_bonding_info_change);
7026 static void netdev_adjacent_add_links(struct net_device *dev)
7028 struct netdev_adjacent *iter;
7030 struct net *net = dev_net(dev);
7032 list_for_each_entry(iter, &dev->adj_list.upper, list) {
7033 if (!net_eq(net, dev_net(iter->dev)))
7035 netdev_adjacent_sysfs_add(iter->dev, dev,
7036 &iter->dev->adj_list.lower);
7037 netdev_adjacent_sysfs_add(dev, iter->dev,
7038 &dev->adj_list.upper);
7041 list_for_each_entry(iter, &dev->adj_list.lower, list) {
7042 if (!net_eq(net, dev_net(iter->dev)))
7044 netdev_adjacent_sysfs_add(iter->dev, dev,
7045 &iter->dev->adj_list.upper);
7046 netdev_adjacent_sysfs_add(dev, iter->dev,
7047 &dev->adj_list.lower);
7051 static void netdev_adjacent_del_links(struct net_device *dev)
7053 struct netdev_adjacent *iter;
7055 struct net *net = dev_net(dev);
7057 list_for_each_entry(iter, &dev->adj_list.upper, list) {
7058 if (!net_eq(net, dev_net(iter->dev)))
7060 netdev_adjacent_sysfs_del(iter->dev, dev->name,
7061 &iter->dev->adj_list.lower);
7062 netdev_adjacent_sysfs_del(dev, iter->dev->name,
7063 &dev->adj_list.upper);
7066 list_for_each_entry(iter, &dev->adj_list.lower, list) {
7067 if (!net_eq(net, dev_net(iter->dev)))
7069 netdev_adjacent_sysfs_del(iter->dev, dev->name,
7070 &iter->dev->adj_list.upper);
7071 netdev_adjacent_sysfs_del(dev, iter->dev->name,
7072 &dev->adj_list.lower);
7076 void netdev_adjacent_rename_links(struct net_device *dev, char *oldname)
7078 struct netdev_adjacent *iter;
7080 struct net *net = dev_net(dev);
7082 list_for_each_entry(iter, &dev->adj_list.upper, list) {
7083 if (!net_eq(net, dev_net(iter->dev)))
7085 netdev_adjacent_sysfs_del(iter->dev, oldname,
7086 &iter->dev->adj_list.lower);
7087 netdev_adjacent_sysfs_add(iter->dev, dev,
7088 &iter->dev->adj_list.lower);
7091 list_for_each_entry(iter, &dev->adj_list.lower, list) {
7092 if (!net_eq(net, dev_net(iter->dev)))
7094 netdev_adjacent_sysfs_del(iter->dev, oldname,
7095 &iter->dev->adj_list.upper);
7096 netdev_adjacent_sysfs_add(iter->dev, dev,
7097 &iter->dev->adj_list.upper);
7101 void *netdev_lower_dev_get_private(struct net_device *dev,
7102 struct net_device *lower_dev)
7104 struct netdev_adjacent *lower;
7108 lower = __netdev_find_adj(lower_dev, &dev->adj_list.lower);
7112 return lower->private;
7114 EXPORT_SYMBOL(netdev_lower_dev_get_private);
7117 int dev_get_nest_level(struct net_device *dev)
7119 struct net_device *lower = NULL;
7120 struct list_head *iter;
7126 netdev_for_each_lower_dev(dev, lower, iter) {
7127 nest = dev_get_nest_level(lower);
7128 if (max_nest < nest)
7132 return max_nest + 1;
7134 EXPORT_SYMBOL(dev_get_nest_level);
7137 * netdev_lower_change - Dispatch event about lower device state change
7138 * @lower_dev: device
7139 * @lower_state_info: state to dispatch
7141 * Send NETDEV_CHANGELOWERSTATE to netdev notifiers with info.
7142 * The caller must hold the RTNL lock.
7144 void netdev_lower_state_changed(struct net_device *lower_dev,
7145 void *lower_state_info)
7147 struct netdev_notifier_changelowerstate_info changelowerstate_info = {
7148 .info.dev = lower_dev,
7152 changelowerstate_info.lower_state_info = lower_state_info;
7153 call_netdevice_notifiers_info(NETDEV_CHANGELOWERSTATE,
7154 &changelowerstate_info.info);
7156 EXPORT_SYMBOL(netdev_lower_state_changed);
7158 static void dev_change_rx_flags(struct net_device *dev, int flags)
7160 const struct net_device_ops *ops = dev->netdev_ops;
7162 if (ops->ndo_change_rx_flags)
7163 ops->ndo_change_rx_flags(dev, flags);
7166 static int __dev_set_promiscuity(struct net_device *dev, int inc, bool notify)
7168 unsigned int old_flags = dev->flags;
7174 dev->flags |= IFF_PROMISC;
7175 dev->promiscuity += inc;
7176 if (dev->promiscuity == 0) {
7179 * If inc causes overflow, untouch promisc and return error.
7182 dev->flags &= ~IFF_PROMISC;
7184 dev->promiscuity -= inc;
7185 pr_warn("%s: promiscuity touches roof, set promiscuity failed. promiscuity feature of device might be broken.\n",
7190 if (dev->flags != old_flags) {
7191 pr_info("device %s %s promiscuous mode\n",
7193 dev->flags & IFF_PROMISC ? "entered" : "left");
7194 if (audit_enabled) {
7195 current_uid_gid(&uid, &gid);
7196 audit_log(audit_context(), GFP_ATOMIC,
7197 AUDIT_ANOM_PROMISCUOUS,
7198 "dev=%s prom=%d old_prom=%d auid=%u uid=%u gid=%u ses=%u",
7199 dev->name, (dev->flags & IFF_PROMISC),
7200 (old_flags & IFF_PROMISC),
7201 from_kuid(&init_user_ns, audit_get_loginuid(current)),
7202 from_kuid(&init_user_ns, uid),
7203 from_kgid(&init_user_ns, gid),
7204 audit_get_sessionid(current));
7207 dev_change_rx_flags(dev, IFF_PROMISC);
7210 __dev_notify_flags(dev, old_flags, IFF_PROMISC);
7215 * dev_set_promiscuity - update promiscuity count on a device
7219 * Add or remove promiscuity from a device. While the count in the device
7220 * remains above zero the interface remains promiscuous. Once it hits zero
7221 * the device reverts back to normal filtering operation. A negative inc
7222 * value is used to drop promiscuity on the device.
7223 * Return 0 if successful or a negative errno code on error.
7225 int dev_set_promiscuity(struct net_device *dev, int inc)
7227 unsigned int old_flags = dev->flags;
7230 err = __dev_set_promiscuity(dev, inc, true);
7233 if (dev->flags != old_flags)
7234 dev_set_rx_mode(dev);
7237 EXPORT_SYMBOL(dev_set_promiscuity);
7239 static int __dev_set_allmulti(struct net_device *dev, int inc, bool notify)
7241 unsigned int old_flags = dev->flags, old_gflags = dev->gflags;
7245 dev->flags |= IFF_ALLMULTI;
7246 dev->allmulti += inc;
7247 if (dev->allmulti == 0) {
7250 * If inc causes overflow, untouch allmulti and return error.
7253 dev->flags &= ~IFF_ALLMULTI;
7255 dev->allmulti -= inc;
7256 pr_warn("%s: allmulti touches roof, set allmulti failed. allmulti feature of device might be broken.\n",
7261 if (dev->flags ^ old_flags) {
7262 dev_change_rx_flags(dev, IFF_ALLMULTI);
7263 dev_set_rx_mode(dev);
7265 __dev_notify_flags(dev, old_flags,
7266 dev->gflags ^ old_gflags);
7272 * dev_set_allmulti - update allmulti count on a device
7276 * Add or remove reception of all multicast frames to a device. While the
7277 * count in the device remains above zero the interface remains listening
7278 * to all interfaces. Once it hits zero the device reverts back to normal
7279 * filtering operation. A negative @inc value is used to drop the counter
7280 * when releasing a resource needing all multicasts.
7281 * Return 0 if successful or a negative errno code on error.
7284 int dev_set_allmulti(struct net_device *dev, int inc)
7286 return __dev_set_allmulti(dev, inc, true);
7288 EXPORT_SYMBOL(dev_set_allmulti);
7291 * Upload unicast and multicast address lists to device and
7292 * configure RX filtering. When the device doesn't support unicast
7293 * filtering it is put in promiscuous mode while unicast addresses
7296 void __dev_set_rx_mode(struct net_device *dev)
7298 const struct net_device_ops *ops = dev->netdev_ops;
7300 /* dev_open will call this function so the list will stay sane. */
7301 if (!(dev->flags&IFF_UP))
7304 if (!netif_device_present(dev))
7307 if (!(dev->priv_flags & IFF_UNICAST_FLT)) {
7308 /* Unicast addresses changes may only happen under the rtnl,
7309 * therefore calling __dev_set_promiscuity here is safe.
7311 if (!netdev_uc_empty(dev) && !dev->uc_promisc) {
7312 __dev_set_promiscuity(dev, 1, false);
7313 dev->uc_promisc = true;
7314 } else if (netdev_uc_empty(dev) && dev->uc_promisc) {
7315 __dev_set_promiscuity(dev, -1, false);
7316 dev->uc_promisc = false;
7320 if (ops->ndo_set_rx_mode)
7321 ops->ndo_set_rx_mode(dev);
7324 void dev_set_rx_mode(struct net_device *dev)
7326 netif_addr_lock_bh(dev);
7327 __dev_set_rx_mode(dev);
7328 netif_addr_unlock_bh(dev);
7332 * dev_get_flags - get flags reported to userspace
7335 * Get the combination of flag bits exported through APIs to userspace.
7337 unsigned int dev_get_flags(const struct net_device *dev)
7341 flags = (dev->flags & ~(IFF_PROMISC |
7346 (dev->gflags & (IFF_PROMISC |
7349 if (netif_running(dev)) {
7350 if (netif_oper_up(dev))
7351 flags |= IFF_RUNNING;
7352 if (netif_carrier_ok(dev))
7353 flags |= IFF_LOWER_UP;
7354 if (netif_dormant(dev))
7355 flags |= IFF_DORMANT;
7360 EXPORT_SYMBOL(dev_get_flags);
7362 int __dev_change_flags(struct net_device *dev, unsigned int flags)
7364 unsigned int old_flags = dev->flags;
7370 * Set the flags on our device.
7373 dev->flags = (flags & (IFF_DEBUG | IFF_NOTRAILERS | IFF_NOARP |
7374 IFF_DYNAMIC | IFF_MULTICAST | IFF_PORTSEL |
7376 (dev->flags & (IFF_UP | IFF_VOLATILE | IFF_PROMISC |
7380 * Load in the correct multicast list now the flags have changed.
7383 if ((old_flags ^ flags) & IFF_MULTICAST)
7384 dev_change_rx_flags(dev, IFF_MULTICAST);
7386 dev_set_rx_mode(dev);
7389 * Have we downed the interface. We handle IFF_UP ourselves
7390 * according to user attempts to set it, rather than blindly
7395 if ((old_flags ^ flags) & IFF_UP) {
7396 if (old_flags & IFF_UP)
7399 ret = __dev_open(dev);
7402 if ((flags ^ dev->gflags) & IFF_PROMISC) {
7403 int inc = (flags & IFF_PROMISC) ? 1 : -1;
7404 unsigned int old_flags = dev->flags;
7406 dev->gflags ^= IFF_PROMISC;
7408 if (__dev_set_promiscuity(dev, inc, false) >= 0)
7409 if (dev->flags != old_flags)
7410 dev_set_rx_mode(dev);
7413 /* NOTE: order of synchronization of IFF_PROMISC and IFF_ALLMULTI
7414 * is important. Some (broken) drivers set IFF_PROMISC, when
7415 * IFF_ALLMULTI is requested not asking us and not reporting.
7417 if ((flags ^ dev->gflags) & IFF_ALLMULTI) {
7418 int inc = (flags & IFF_ALLMULTI) ? 1 : -1;
7420 dev->gflags ^= IFF_ALLMULTI;
7421 __dev_set_allmulti(dev, inc, false);
7427 void __dev_notify_flags(struct net_device *dev, unsigned int old_flags,
7428 unsigned int gchanges)
7430 unsigned int changes = dev->flags ^ old_flags;
7433 rtmsg_ifinfo(RTM_NEWLINK, dev, gchanges, GFP_ATOMIC);
7435 if (changes & IFF_UP) {
7436 if (dev->flags & IFF_UP)
7437 call_netdevice_notifiers(NETDEV_UP, dev);
7439 call_netdevice_notifiers(NETDEV_DOWN, dev);
7442 if (dev->flags & IFF_UP &&
7443 (changes & ~(IFF_UP | IFF_PROMISC | IFF_ALLMULTI | IFF_VOLATILE))) {
7444 struct netdev_notifier_change_info change_info = {
7448 .flags_changed = changes,
7451 call_netdevice_notifiers_info(NETDEV_CHANGE, &change_info.info);
7456 * dev_change_flags - change device settings
7458 * @flags: device state flags
7460 * Change settings on device based state flags. The flags are
7461 * in the userspace exported format.
7463 int dev_change_flags(struct net_device *dev, unsigned int flags)
7466 unsigned int changes, old_flags = dev->flags, old_gflags = dev->gflags;
7468 ret = __dev_change_flags(dev, flags);
7472 changes = (old_flags ^ dev->flags) | (old_gflags ^ dev->gflags);
7473 __dev_notify_flags(dev, old_flags, changes);
7476 EXPORT_SYMBOL(dev_change_flags);
7478 int __dev_set_mtu(struct net_device *dev, int new_mtu)
7480 const struct net_device_ops *ops = dev->netdev_ops;
7482 if (ops->ndo_change_mtu)
7483 return ops->ndo_change_mtu(dev, new_mtu);
7488 EXPORT_SYMBOL(__dev_set_mtu);
7491 * dev_set_mtu - Change maximum transfer unit
7493 * @new_mtu: new transfer unit
7495 * Change the maximum transfer size of the network device.
7497 int dev_set_mtu(struct net_device *dev, int new_mtu)
7501 if (new_mtu == dev->mtu)
7504 /* MTU must be positive, and in range */
7505 if (new_mtu < 0 || new_mtu < dev->min_mtu) {
7506 net_err_ratelimited("%s: Invalid MTU %d requested, hw min %d\n",
7507 dev->name, new_mtu, dev->min_mtu);
7511 if (dev->max_mtu > 0 && new_mtu > dev->max_mtu) {
7512 net_err_ratelimited("%s: Invalid MTU %d requested, hw max %d\n",
7513 dev->name, new_mtu, dev->max_mtu);
7517 if (!netif_device_present(dev))
7520 err = call_netdevice_notifiers(NETDEV_PRECHANGEMTU, dev);
7521 err = notifier_to_errno(err);
7525 orig_mtu = dev->mtu;
7526 err = __dev_set_mtu(dev, new_mtu);
7529 err = call_netdevice_notifiers(NETDEV_CHANGEMTU, dev);
7530 err = notifier_to_errno(err);
7532 /* setting mtu back and notifying everyone again,
7533 * so that they have a chance to revert changes.
7535 __dev_set_mtu(dev, orig_mtu);
7536 call_netdevice_notifiers(NETDEV_CHANGEMTU, dev);
7541 EXPORT_SYMBOL(dev_set_mtu);
7544 * dev_change_tx_queue_len - Change TX queue length of a netdevice
7546 * @new_len: new tx queue length
7548 int dev_change_tx_queue_len(struct net_device *dev, unsigned long new_len)
7550 unsigned int orig_len = dev->tx_queue_len;
7553 if (new_len != (unsigned int)new_len)
7556 if (new_len != orig_len) {
7557 dev->tx_queue_len = new_len;
7558 res = call_netdevice_notifiers(NETDEV_CHANGE_TX_QUEUE_LEN, dev);
7559 res = notifier_to_errno(res);
7562 "refused to change device tx_queue_len\n");
7563 dev->tx_queue_len = orig_len;
7566 return dev_qdisc_change_tx_queue_len(dev);
7573 * dev_set_group - Change group this device belongs to
7575 * @new_group: group this device should belong to
7577 void dev_set_group(struct net_device *dev, int new_group)
7579 dev->group = new_group;
7581 EXPORT_SYMBOL(dev_set_group);
7584 * dev_set_mac_address - Change Media Access Control Address
7588 * Change the hardware (MAC) address of the device
7590 int dev_set_mac_address(struct net_device *dev, struct sockaddr *sa)
7592 const struct net_device_ops *ops = dev->netdev_ops;
7595 if (!ops->ndo_set_mac_address)
7597 if (sa->sa_family != dev->type)
7599 if (!netif_device_present(dev))
7601 err = ops->ndo_set_mac_address(dev, sa);
7604 dev->addr_assign_type = NET_ADDR_SET;
7605 call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
7606 add_device_randomness(dev->dev_addr, dev->addr_len);
7609 EXPORT_SYMBOL(dev_set_mac_address);
7612 * dev_change_carrier - Change device carrier
7614 * @new_carrier: new value
7616 * Change device carrier
7618 int dev_change_carrier(struct net_device *dev, bool new_carrier)
7620 const struct net_device_ops *ops = dev->netdev_ops;
7622 if (!ops->ndo_change_carrier)
7624 if (!netif_device_present(dev))
7626 return ops->ndo_change_carrier(dev, new_carrier);
7628 EXPORT_SYMBOL(dev_change_carrier);
7631 * dev_get_phys_port_id - Get device physical port ID
7635 * Get device physical port ID
7637 int dev_get_phys_port_id(struct net_device *dev,
7638 struct netdev_phys_item_id *ppid)
7640 const struct net_device_ops *ops = dev->netdev_ops;
7642 if (!ops->ndo_get_phys_port_id)
7644 return ops->ndo_get_phys_port_id(dev, ppid);
7646 EXPORT_SYMBOL(dev_get_phys_port_id);
7649 * dev_get_phys_port_name - Get device physical port name
7652 * @len: limit of bytes to copy to name
7654 * Get device physical port name
7656 int dev_get_phys_port_name(struct net_device *dev,
7657 char *name, size_t len)
7659 const struct net_device_ops *ops = dev->netdev_ops;
7661 if (!ops->ndo_get_phys_port_name)
7663 return ops->ndo_get_phys_port_name(dev, name, len);
7665 EXPORT_SYMBOL(dev_get_phys_port_name);
7668 * dev_change_proto_down - update protocol port state information
7670 * @proto_down: new value
7672 * This info can be used by switch drivers to set the phys state of the
7675 int dev_change_proto_down(struct net_device *dev, bool proto_down)
7677 const struct net_device_ops *ops = dev->netdev_ops;
7679 if (!ops->ndo_change_proto_down)
7681 if (!netif_device_present(dev))
7683 return ops->ndo_change_proto_down(dev, proto_down);
7685 EXPORT_SYMBOL(dev_change_proto_down);
7687 void __dev_xdp_query(struct net_device *dev, bpf_op_t bpf_op,
7688 struct netdev_bpf *xdp)
7690 memset(xdp, 0, sizeof(*xdp));
7691 xdp->command = XDP_QUERY_PROG;
7693 /* Query must always succeed. */
7694 WARN_ON(bpf_op(dev, xdp) < 0);
7697 static u8 __dev_xdp_attached(struct net_device *dev, bpf_op_t bpf_op)
7699 struct netdev_bpf xdp;
7701 __dev_xdp_query(dev, bpf_op, &xdp);
7703 return xdp.prog_attached;
7706 static int dev_xdp_install(struct net_device *dev, bpf_op_t bpf_op,
7707 struct netlink_ext_ack *extack, u32 flags,
7708 struct bpf_prog *prog)
7710 struct netdev_bpf xdp;
7712 memset(&xdp, 0, sizeof(xdp));
7713 if (flags & XDP_FLAGS_HW_MODE)
7714 xdp.command = XDP_SETUP_PROG_HW;
7716 xdp.command = XDP_SETUP_PROG;
7717 xdp.extack = extack;
7721 return bpf_op(dev, &xdp);
7724 static void dev_xdp_uninstall(struct net_device *dev)
7726 struct netdev_bpf xdp;
7729 /* Remove generic XDP */
7730 WARN_ON(dev_xdp_install(dev, generic_xdp_install, NULL, 0, NULL));
7732 /* Remove from the driver */
7733 ndo_bpf = dev->netdev_ops->ndo_bpf;
7737 __dev_xdp_query(dev, ndo_bpf, &xdp);
7738 if (xdp.prog_attached == XDP_ATTACHED_NONE)
7741 /* Program removal should always succeed */
7742 WARN_ON(dev_xdp_install(dev, ndo_bpf, NULL, xdp.prog_flags, NULL));
7746 * dev_change_xdp_fd - set or clear a bpf program for a device rx path
7748 * @extack: netlink extended ack
7749 * @fd: new program fd or negative value to clear
7750 * @flags: xdp-related flags
7752 * Set or clear a bpf program for a device
7754 int dev_change_xdp_fd(struct net_device *dev, struct netlink_ext_ack *extack,
7757 const struct net_device_ops *ops = dev->netdev_ops;
7758 struct bpf_prog *prog = NULL;
7759 bpf_op_t bpf_op, bpf_chk;
7764 bpf_op = bpf_chk = ops->ndo_bpf;
7765 if (!bpf_op && (flags & (XDP_FLAGS_DRV_MODE | XDP_FLAGS_HW_MODE)))
7767 if (!bpf_op || (flags & XDP_FLAGS_SKB_MODE))
7768 bpf_op = generic_xdp_install;
7769 if (bpf_op == bpf_chk)
7770 bpf_chk = generic_xdp_install;
7773 if (bpf_chk && __dev_xdp_attached(dev, bpf_chk))
7775 if ((flags & XDP_FLAGS_UPDATE_IF_NOEXIST) &&
7776 __dev_xdp_attached(dev, bpf_op))
7779 prog = bpf_prog_get_type_dev(fd, BPF_PROG_TYPE_XDP,
7780 bpf_op == ops->ndo_bpf);
7782 return PTR_ERR(prog);
7784 if (!(flags & XDP_FLAGS_HW_MODE) &&
7785 bpf_prog_is_dev_bound(prog->aux)) {
7786 NL_SET_ERR_MSG(extack, "using device-bound program without HW_MODE flag is not supported");
7792 err = dev_xdp_install(dev, bpf_op, extack, flags, prog);
7793 if (err < 0 && prog)
7800 * dev_new_index - allocate an ifindex
7801 * @net: the applicable net namespace
7803 * Returns a suitable unique value for a new device interface
7804 * number. The caller must hold the rtnl semaphore or the
7805 * dev_base_lock to be sure it remains unique.
7807 static int dev_new_index(struct net *net)
7809 int ifindex = net->ifindex;
7814 if (!__dev_get_by_index(net, ifindex))
7815 return net->ifindex = ifindex;
7819 /* Delayed registration/unregisteration */
7820 static LIST_HEAD(net_todo_list);
7821 DECLARE_WAIT_QUEUE_HEAD(netdev_unregistering_wq);
7823 static void net_set_todo(struct net_device *dev)
7825 list_add_tail(&dev->todo_list, &net_todo_list);
7826 dev_net(dev)->dev_unreg_count++;
7829 static void rollback_registered_many(struct list_head *head)
7831 struct net_device *dev, *tmp;
7832 LIST_HEAD(close_head);
7834 BUG_ON(dev_boot_phase);
7837 list_for_each_entry_safe(dev, tmp, head, unreg_list) {
7838 /* Some devices call without registering
7839 * for initialization unwind. Remove those
7840 * devices and proceed with the remaining.
7842 if (dev->reg_state == NETREG_UNINITIALIZED) {
7843 pr_debug("unregister_netdevice: device %s/%p never was registered\n",
7847 list_del(&dev->unreg_list);
7850 dev->dismantle = true;
7851 BUG_ON(dev->reg_state != NETREG_REGISTERED);
7854 /* If device is running, close it first. */
7855 list_for_each_entry(dev, head, unreg_list)
7856 list_add_tail(&dev->close_list, &close_head);
7857 dev_close_many(&close_head, true);
7859 list_for_each_entry(dev, head, unreg_list) {
7860 /* And unlink it from device chain. */
7861 unlist_netdevice(dev);
7863 dev->reg_state = NETREG_UNREGISTERING;
7865 flush_all_backlogs();
7869 list_for_each_entry(dev, head, unreg_list) {
7870 struct sk_buff *skb = NULL;
7872 /* Shutdown queueing discipline. */
7875 dev_xdp_uninstall(dev);
7877 /* Notify protocols, that we are about to destroy
7878 * this device. They should clean all the things.
7880 call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
7882 if (!dev->rtnl_link_ops ||
7883 dev->rtnl_link_state == RTNL_LINK_INITIALIZED)
7884 skb = rtmsg_ifinfo_build_skb(RTM_DELLINK, dev, ~0U, 0,
7885 GFP_KERNEL, NULL, 0);
7888 * Flush the unicast and multicast chains
7893 if (dev->netdev_ops->ndo_uninit)
7894 dev->netdev_ops->ndo_uninit(dev);
7897 rtmsg_ifinfo_send(skb, dev, GFP_KERNEL);
7899 /* Notifier chain MUST detach us all upper devices. */
7900 WARN_ON(netdev_has_any_upper_dev(dev));
7901 WARN_ON(netdev_has_any_lower_dev(dev));
7903 /* Remove entries from kobject tree */
7904 netdev_unregister_kobject(dev);
7906 /* Remove XPS queueing entries */
7907 netif_reset_xps_queues_gt(dev, 0);
7913 list_for_each_entry(dev, head, unreg_list)
7917 static void rollback_registered(struct net_device *dev)
7921 list_add(&dev->unreg_list, &single);
7922 rollback_registered_many(&single);
7926 static netdev_features_t netdev_sync_upper_features(struct net_device *lower,
7927 struct net_device *upper, netdev_features_t features)
7929 netdev_features_t upper_disables = NETIF_F_UPPER_DISABLES;
7930 netdev_features_t feature;
7933 for_each_netdev_feature(&upper_disables, feature_bit) {
7934 feature = __NETIF_F_BIT(feature_bit);
7935 if (!(upper->wanted_features & feature)
7936 && (features & feature)) {
7937 netdev_dbg(lower, "Dropping feature %pNF, upper dev %s has it off.\n",
7938 &feature, upper->name);
7939 features &= ~feature;
7946 static void netdev_sync_lower_features(struct net_device *upper,
7947 struct net_device *lower, netdev_features_t features)
7949 netdev_features_t upper_disables = NETIF_F_UPPER_DISABLES;
7950 netdev_features_t feature;
7953 for_each_netdev_feature(&upper_disables, feature_bit) {
7954 feature = __NETIF_F_BIT(feature_bit);
7955 if (!(features & feature) && (lower->features & feature)) {
7956 netdev_dbg(upper, "Disabling feature %pNF on lower dev %s.\n",
7957 &feature, lower->name);
7958 lower->wanted_features &= ~feature;
7959 netdev_update_features(lower);
7961 if (unlikely(lower->features & feature))
7962 netdev_WARN(upper, "failed to disable %pNF on %s!\n",
7963 &feature, lower->name);
7968 static netdev_features_t netdev_fix_features(struct net_device *dev,
7969 netdev_features_t features)
7971 /* Fix illegal checksum combinations */
7972 if ((features & NETIF_F_HW_CSUM) &&
7973 (features & (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))) {
7974 netdev_warn(dev, "mixed HW and IP checksum settings.\n");
7975 features &= ~(NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM);
7978 /* TSO requires that SG is present as well. */
7979 if ((features & NETIF_F_ALL_TSO) && !(features & NETIF_F_SG)) {
7980 netdev_dbg(dev, "Dropping TSO features since no SG feature.\n");
7981 features &= ~NETIF_F_ALL_TSO;
7984 if ((features & NETIF_F_TSO) && !(features & NETIF_F_HW_CSUM) &&
7985 !(features & NETIF_F_IP_CSUM)) {
7986 netdev_dbg(dev, "Dropping TSO features since no CSUM feature.\n");
7987 features &= ~NETIF_F_TSO;
7988 features &= ~NETIF_F_TSO_ECN;
7991 if ((features & NETIF_F_TSO6) && !(features & NETIF_F_HW_CSUM) &&
7992 !(features & NETIF_F_IPV6_CSUM)) {
7993 netdev_dbg(dev, "Dropping TSO6 features since no CSUM feature.\n");
7994 features &= ~NETIF_F_TSO6;
7997 /* TSO with IPv4 ID mangling requires IPv4 TSO be enabled */
7998 if ((features & NETIF_F_TSO_MANGLEID) && !(features & NETIF_F_TSO))
7999 features &= ~NETIF_F_TSO_MANGLEID;
8001 /* TSO ECN requires that TSO is present as well. */
8002 if ((features & NETIF_F_ALL_TSO) == NETIF_F_TSO_ECN)
8003 features &= ~NETIF_F_TSO_ECN;
8005 /* Software GSO depends on SG. */
8006 if ((features & NETIF_F_GSO) && !(features & NETIF_F_SG)) {
8007 netdev_dbg(dev, "Dropping NETIF_F_GSO since no SG feature.\n");
8008 features &= ~NETIF_F_GSO;
8011 /* GSO partial features require GSO partial be set */
8012 if ((features & dev->gso_partial_features) &&
8013 !(features & NETIF_F_GSO_PARTIAL)) {
8015 "Dropping partially supported GSO features since no GSO partial.\n");
8016 features &= ~dev->gso_partial_features;
8019 if (!(features & NETIF_F_RXCSUM)) {
8020 /* NETIF_F_GRO_HW implies doing RXCSUM since every packet
8021 * successfully merged by hardware must also have the
8022 * checksum verified by hardware. If the user does not
8023 * want to enable RXCSUM, logically, we should disable GRO_HW.
8025 if (features & NETIF_F_GRO_HW) {
8026 netdev_dbg(dev, "Dropping NETIF_F_GRO_HW since no RXCSUM feature.\n");
8027 features &= ~NETIF_F_GRO_HW;
8031 /* LRO/HW-GRO features cannot be combined with RX-FCS */
8032 if (features & NETIF_F_RXFCS) {
8033 if (features & NETIF_F_LRO) {
8034 netdev_dbg(dev, "Dropping LRO feature since RX-FCS is requested.\n");
8035 features &= ~NETIF_F_LRO;
8038 if (features & NETIF_F_GRO_HW) {
8039 netdev_dbg(dev, "Dropping HW-GRO feature since RX-FCS is requested.\n");
8040 features &= ~NETIF_F_GRO_HW;
8047 int __netdev_update_features(struct net_device *dev)
8049 struct net_device *upper, *lower;
8050 netdev_features_t features;
8051 struct list_head *iter;
8056 features = netdev_get_wanted_features(dev);
8058 if (dev->netdev_ops->ndo_fix_features)
8059 features = dev->netdev_ops->ndo_fix_features(dev, features);
8061 /* driver might be less strict about feature dependencies */
8062 features = netdev_fix_features(dev, features);
8064 /* some features can't be enabled if they're off an an upper device */
8065 netdev_for_each_upper_dev_rcu(dev, upper, iter)
8066 features = netdev_sync_upper_features(dev, upper, features);
8068 if (dev->features == features)
8071 netdev_dbg(dev, "Features changed: %pNF -> %pNF\n",
8072 &dev->features, &features);
8074 if (dev->netdev_ops->ndo_set_features)
8075 err = dev->netdev_ops->ndo_set_features(dev, features);
8079 if (unlikely(err < 0)) {
8081 "set_features() failed (%d); wanted %pNF, left %pNF\n",
8082 err, &features, &dev->features);
8083 /* return non-0 since some features might have changed and
8084 * it's better to fire a spurious notification than miss it
8090 /* some features must be disabled on lower devices when disabled
8091 * on an upper device (think: bonding master or bridge)
8093 netdev_for_each_lower_dev(dev, lower, iter)
8094 netdev_sync_lower_features(dev, lower, features);
8097 netdev_features_t diff = features ^ dev->features;
8099 if (diff & NETIF_F_RX_UDP_TUNNEL_PORT) {
8100 /* udp_tunnel_{get,drop}_rx_info both need
8101 * NETIF_F_RX_UDP_TUNNEL_PORT enabled on the
8102 * device, or they won't do anything.
8103 * Thus we need to update dev->features
8104 * *before* calling udp_tunnel_get_rx_info,
8105 * but *after* calling udp_tunnel_drop_rx_info.
8107 if (features & NETIF_F_RX_UDP_TUNNEL_PORT) {
8108 dev->features = features;
8109 udp_tunnel_get_rx_info(dev);
8111 udp_tunnel_drop_rx_info(dev);
8115 if (diff & NETIF_F_HW_VLAN_CTAG_FILTER) {
8116 if (features & NETIF_F_HW_VLAN_CTAG_FILTER) {
8117 dev->features = features;
8118 err |= vlan_get_rx_ctag_filter_info(dev);
8120 vlan_drop_rx_ctag_filter_info(dev);
8124 if (diff & NETIF_F_HW_VLAN_STAG_FILTER) {
8125 if (features & NETIF_F_HW_VLAN_STAG_FILTER) {
8126 dev->features = features;
8127 err |= vlan_get_rx_stag_filter_info(dev);
8129 vlan_drop_rx_stag_filter_info(dev);
8133 dev->features = features;
8136 return err < 0 ? 0 : 1;
8140 * netdev_update_features - recalculate device features
8141 * @dev: the device to check
8143 * Recalculate dev->features set and send notifications if it
8144 * has changed. Should be called after driver or hardware dependent
8145 * conditions might have changed that influence the features.
8147 void netdev_update_features(struct net_device *dev)
8149 if (__netdev_update_features(dev))
8150 netdev_features_change(dev);
8152 EXPORT_SYMBOL(netdev_update_features);
8155 * netdev_change_features - recalculate device features
8156 * @dev: the device to check
8158 * Recalculate dev->features set and send notifications even
8159 * if they have not changed. Should be called instead of
8160 * netdev_update_features() if also dev->vlan_features might
8161 * have changed to allow the changes to be propagated to stacked
8164 void netdev_change_features(struct net_device *dev)
8166 __netdev_update_features(dev);
8167 netdev_features_change(dev);
8169 EXPORT_SYMBOL(netdev_change_features);
8172 * netif_stacked_transfer_operstate - transfer operstate
8173 * @rootdev: the root or lower level device to transfer state from
8174 * @dev: the device to transfer operstate to
8176 * Transfer operational state from root to device. This is normally
8177 * called when a stacking relationship exists between the root
8178 * device and the device(a leaf device).
8180 void netif_stacked_transfer_operstate(const struct net_device *rootdev,
8181 struct net_device *dev)
8183 if (rootdev->operstate == IF_OPER_DORMANT)
8184 netif_dormant_on(dev);
8186 netif_dormant_off(dev);
8188 if (netif_carrier_ok(rootdev))
8189 netif_carrier_on(dev);
8191 netif_carrier_off(dev);
8193 EXPORT_SYMBOL(netif_stacked_transfer_operstate);
8195 static int netif_alloc_rx_queues(struct net_device *dev)
8197 unsigned int i, count = dev->num_rx_queues;
8198 struct netdev_rx_queue *rx;
8199 size_t sz = count * sizeof(*rx);
8204 rx = kvzalloc(sz, GFP_KERNEL | __GFP_RETRY_MAYFAIL);
8210 for (i = 0; i < count; i++) {
8213 /* XDP RX-queue setup */
8214 err = xdp_rxq_info_reg(&rx[i].xdp_rxq, dev, i);
8221 /* Rollback successful reg's and free other resources */
8223 xdp_rxq_info_unreg(&rx[i].xdp_rxq);
8229 static void netif_free_rx_queues(struct net_device *dev)
8231 unsigned int i, count = dev->num_rx_queues;
8233 /* netif_alloc_rx_queues alloc failed, resources have been unreg'ed */
8237 for (i = 0; i < count; i++)
8238 xdp_rxq_info_unreg(&dev->_rx[i].xdp_rxq);
8243 static void netdev_init_one_queue(struct net_device *dev,
8244 struct netdev_queue *queue, void *_unused)
8246 /* Initialize queue lock */
8247 spin_lock_init(&queue->_xmit_lock);
8248 netdev_set_xmit_lockdep_class(&queue->_xmit_lock, dev->type);
8249 queue->xmit_lock_owner = -1;
8250 netdev_queue_numa_node_write(queue, NUMA_NO_NODE);
8253 dql_init(&queue->dql, HZ);
8257 static void netif_free_tx_queues(struct net_device *dev)
8262 static int netif_alloc_netdev_queues(struct net_device *dev)
8264 unsigned int count = dev->num_tx_queues;
8265 struct netdev_queue *tx;
8266 size_t sz = count * sizeof(*tx);
8268 if (count < 1 || count > 0xffff)
8271 tx = kvzalloc(sz, GFP_KERNEL | __GFP_RETRY_MAYFAIL);
8277 netdev_for_each_tx_queue(dev, netdev_init_one_queue, NULL);
8278 spin_lock_init(&dev->tx_global_lock);
8283 void netif_tx_stop_all_queues(struct net_device *dev)
8287 for (i = 0; i < dev->num_tx_queues; i++) {
8288 struct netdev_queue *txq = netdev_get_tx_queue(dev, i);
8290 netif_tx_stop_queue(txq);
8293 EXPORT_SYMBOL(netif_tx_stop_all_queues);
8296 * register_netdevice - register a network device
8297 * @dev: device to register
8299 * Take a completed network device structure and add it to the kernel
8300 * interfaces. A %NETDEV_REGISTER message is sent to the netdev notifier
8301 * chain. 0 is returned on success. A negative errno code is returned
8302 * on a failure to set up the device, or if the name is a duplicate.
8304 * Callers must hold the rtnl semaphore. You may want
8305 * register_netdev() instead of this.
8308 * The locking appears insufficient to guarantee two parallel registers
8309 * will not get the same name.
8312 int register_netdevice(struct net_device *dev)
8315 struct net *net = dev_net(dev);
8317 BUILD_BUG_ON(sizeof(netdev_features_t) * BITS_PER_BYTE <
8318 NETDEV_FEATURE_COUNT);
8319 BUG_ON(dev_boot_phase);
8324 /* When net_device's are persistent, this will be fatal. */
8325 BUG_ON(dev->reg_state != NETREG_UNINITIALIZED);
8328 spin_lock_init(&dev->addr_list_lock);
8329 netdev_set_addr_lockdep_class(dev);
8331 ret = dev_get_valid_name(net, dev, dev->name);
8335 /* Init, if this function is available */
8336 if (dev->netdev_ops->ndo_init) {
8337 ret = dev->netdev_ops->ndo_init(dev);
8345 if (((dev->hw_features | dev->features) &
8346 NETIF_F_HW_VLAN_CTAG_FILTER) &&
8347 (!dev->netdev_ops->ndo_vlan_rx_add_vid ||
8348 !dev->netdev_ops->ndo_vlan_rx_kill_vid)) {
8349 netdev_WARN(dev, "Buggy VLAN acceleration in driver!\n");
8356 dev->ifindex = dev_new_index(net);
8357 else if (__dev_get_by_index(net, dev->ifindex))
8360 /* Transfer changeable features to wanted_features and enable
8361 * software offloads (GSO and GRO).
8363 dev->hw_features |= NETIF_F_SOFT_FEATURES;
8364 dev->features |= NETIF_F_SOFT_FEATURES;
8366 if (dev->netdev_ops->ndo_udp_tunnel_add) {
8367 dev->features |= NETIF_F_RX_UDP_TUNNEL_PORT;
8368 dev->hw_features |= NETIF_F_RX_UDP_TUNNEL_PORT;
8371 dev->wanted_features = dev->features & dev->hw_features;
8373 if (!(dev->flags & IFF_LOOPBACK))
8374 dev->hw_features |= NETIF_F_NOCACHE_COPY;
8376 /* If IPv4 TCP segmentation offload is supported we should also
8377 * allow the device to enable segmenting the frame with the option
8378 * of ignoring a static IP ID value. This doesn't enable the
8379 * feature itself but allows the user to enable it later.
8381 if (dev->hw_features & NETIF_F_TSO)
8382 dev->hw_features |= NETIF_F_TSO_MANGLEID;
8383 if (dev->vlan_features & NETIF_F_TSO)
8384 dev->vlan_features |= NETIF_F_TSO_MANGLEID;
8385 if (dev->mpls_features & NETIF_F_TSO)
8386 dev->mpls_features |= NETIF_F_TSO_MANGLEID;
8387 if (dev->hw_enc_features & NETIF_F_TSO)
8388 dev->hw_enc_features |= NETIF_F_TSO_MANGLEID;
8390 /* Make NETIF_F_HIGHDMA inheritable to VLAN devices.
8392 dev->vlan_features |= NETIF_F_HIGHDMA;
8394 /* Make NETIF_F_SG inheritable to tunnel devices.
8396 dev->hw_enc_features |= NETIF_F_SG | NETIF_F_GSO_PARTIAL;
8398 /* Make NETIF_F_SG inheritable to MPLS.
8400 dev->mpls_features |= NETIF_F_SG;
8402 ret = call_netdevice_notifiers(NETDEV_POST_INIT, dev);
8403 ret = notifier_to_errno(ret);
8407 ret = netdev_register_kobject(dev);
8410 dev->reg_state = NETREG_REGISTERED;
8412 __netdev_update_features(dev);
8415 * Default initial state at registry is that the
8416 * device is present.
8419 set_bit(__LINK_STATE_PRESENT, &dev->state);
8421 linkwatch_init_dev(dev);
8423 dev_init_scheduler(dev);
8425 list_netdevice(dev);
8426 add_device_randomness(dev->dev_addr, dev->addr_len);
8428 /* If the device has permanent device address, driver should
8429 * set dev_addr and also addr_assign_type should be set to
8430 * NET_ADDR_PERM (default value).
8432 if (dev->addr_assign_type == NET_ADDR_PERM)
8433 memcpy(dev->perm_addr, dev->dev_addr, dev->addr_len);
8435 /* Notify protocols, that a new device appeared. */
8436 ret = call_netdevice_notifiers(NETDEV_REGISTER, dev);
8437 ret = notifier_to_errno(ret);
8439 rollback_registered(dev);
8440 dev->reg_state = NETREG_UNREGISTERED;
8443 * Prevent userspace races by waiting until the network
8444 * device is fully setup before sending notifications.
8446 if (!dev->rtnl_link_ops ||
8447 dev->rtnl_link_state == RTNL_LINK_INITIALIZED)
8448 rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U, GFP_KERNEL);
8454 if (dev->netdev_ops->ndo_uninit)
8455 dev->netdev_ops->ndo_uninit(dev);
8456 if (dev->priv_destructor)
8457 dev->priv_destructor(dev);
8460 EXPORT_SYMBOL(register_netdevice);
8463 * init_dummy_netdev - init a dummy network device for NAPI
8464 * @dev: device to init
8466 * This takes a network device structure and initialize the minimum
8467 * amount of fields so it can be used to schedule NAPI polls without
8468 * registering a full blown interface. This is to be used by drivers
8469 * that need to tie several hardware interfaces to a single NAPI
8470 * poll scheduler due to HW limitations.
8472 int init_dummy_netdev(struct net_device *dev)
8474 /* Clear everything. Note we don't initialize spinlocks
8475 * are they aren't supposed to be taken by any of the
8476 * NAPI code and this dummy netdev is supposed to be
8477 * only ever used for NAPI polls
8479 memset(dev, 0, sizeof(struct net_device));
8481 /* make sure we BUG if trying to hit standard
8482 * register/unregister code path
8484 dev->reg_state = NETREG_DUMMY;
8486 /* NAPI wants this */
8487 INIT_LIST_HEAD(&dev->napi_list);
8489 /* a dummy interface is started by default */
8490 set_bit(__LINK_STATE_PRESENT, &dev->state);
8491 set_bit(__LINK_STATE_START, &dev->state);
8493 /* Note : We dont allocate pcpu_refcnt for dummy devices,
8494 * because users of this 'device' dont need to change
8500 EXPORT_SYMBOL_GPL(init_dummy_netdev);
8504 * register_netdev - register a network device
8505 * @dev: device to register
8507 * Take a completed network device structure and add it to the kernel
8508 * interfaces. A %NETDEV_REGISTER message is sent to the netdev notifier
8509 * chain. 0 is returned on success. A negative errno code is returned
8510 * on a failure to set up the device, or if the name is a duplicate.
8512 * This is a wrapper around register_netdevice that takes the rtnl semaphore
8513 * and expands the device name if you passed a format string to
8516 int register_netdev(struct net_device *dev)
8520 if (rtnl_lock_killable())
8522 err = register_netdevice(dev);
8526 EXPORT_SYMBOL(register_netdev);
8528 int netdev_refcnt_read(const struct net_device *dev)
8532 for_each_possible_cpu(i)
8533 refcnt += *per_cpu_ptr(dev->pcpu_refcnt, i);
8536 EXPORT_SYMBOL(netdev_refcnt_read);
8539 * netdev_wait_allrefs - wait until all references are gone.
8540 * @dev: target net_device
8542 * This is called when unregistering network devices.
8544 * Any protocol or device that holds a reference should register
8545 * for netdevice notification, and cleanup and put back the
8546 * reference if they receive an UNREGISTER event.
8547 * We can get stuck here if buggy protocols don't correctly
8550 static void netdev_wait_allrefs(struct net_device *dev)
8552 unsigned long rebroadcast_time, warning_time;
8555 linkwatch_forget_dev(dev);
8557 rebroadcast_time = warning_time = jiffies;
8558 refcnt = netdev_refcnt_read(dev);
8560 while (refcnt != 0) {
8561 if (time_after(jiffies, rebroadcast_time + 1 * HZ)) {
8564 /* Rebroadcast unregister notification */
8565 call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
8571 if (test_bit(__LINK_STATE_LINKWATCH_PENDING,
8573 /* We must not have linkwatch events
8574 * pending on unregister. If this
8575 * happens, we simply run the queue
8576 * unscheduled, resulting in a noop
8579 linkwatch_run_queue();
8584 rebroadcast_time = jiffies;
8589 refcnt = netdev_refcnt_read(dev);
8591 if (time_after(jiffies, warning_time + 10 * HZ)) {
8592 pr_emerg("unregister_netdevice: waiting for %s to become free. Usage count = %d\n",
8594 warning_time = jiffies;
8603 * register_netdevice(x1);
8604 * register_netdevice(x2);
8606 * unregister_netdevice(y1);
8607 * unregister_netdevice(y2);
8613 * We are invoked by rtnl_unlock().
8614 * This allows us to deal with problems:
8615 * 1) We can delete sysfs objects which invoke hotplug
8616 * without deadlocking with linkwatch via keventd.
8617 * 2) Since we run with the RTNL semaphore not held, we can sleep
8618 * safely in order to wait for the netdev refcnt to drop to zero.
8620 * We must not return until all unregister events added during
8621 * the interval the lock was held have been completed.
8623 void netdev_run_todo(void)
8625 struct list_head list;
8627 /* Snapshot list, allow later requests */
8628 list_replace_init(&net_todo_list, &list);
8633 /* Wait for rcu callbacks to finish before next phase */
8634 if (!list_empty(&list))
8637 while (!list_empty(&list)) {
8638 struct net_device *dev
8639 = list_first_entry(&list, struct net_device, todo_list);
8640 list_del(&dev->todo_list);
8642 if (unlikely(dev->reg_state != NETREG_UNREGISTERING)) {
8643 pr_err("network todo '%s' but state %d\n",
8644 dev->name, dev->reg_state);
8649 dev->reg_state = NETREG_UNREGISTERED;
8651 netdev_wait_allrefs(dev);
8654 BUG_ON(netdev_refcnt_read(dev));
8655 BUG_ON(!list_empty(&dev->ptype_all));
8656 BUG_ON(!list_empty(&dev->ptype_specific));
8657 WARN_ON(rcu_access_pointer(dev->ip_ptr));
8658 WARN_ON(rcu_access_pointer(dev->ip6_ptr));
8659 #if IS_ENABLED(CONFIG_DECNET)
8660 WARN_ON(dev->dn_ptr);
8662 if (dev->priv_destructor)
8663 dev->priv_destructor(dev);
8664 if (dev->needs_free_netdev)
8667 /* Report a network device has been unregistered */
8669 dev_net(dev)->dev_unreg_count--;
8671 wake_up(&netdev_unregistering_wq);
8673 /* Free network device */
8674 kobject_put(&dev->dev.kobj);
8678 /* Convert net_device_stats to rtnl_link_stats64. rtnl_link_stats64 has
8679 * all the same fields in the same order as net_device_stats, with only
8680 * the type differing, but rtnl_link_stats64 may have additional fields
8681 * at the end for newer counters.
8683 void netdev_stats_to_stats64(struct rtnl_link_stats64 *stats64,
8684 const struct net_device_stats *netdev_stats)
8686 #if BITS_PER_LONG == 64
8687 BUILD_BUG_ON(sizeof(*stats64) < sizeof(*netdev_stats));
8688 memcpy(stats64, netdev_stats, sizeof(*netdev_stats));
8689 /* zero out counters that only exist in rtnl_link_stats64 */
8690 memset((char *)stats64 + sizeof(*netdev_stats), 0,
8691 sizeof(*stats64) - sizeof(*netdev_stats));
8693 size_t i, n = sizeof(*netdev_stats) / sizeof(unsigned long);
8694 const unsigned long *src = (const unsigned long *)netdev_stats;
8695 u64 *dst = (u64 *)stats64;
8697 BUILD_BUG_ON(n > sizeof(*stats64) / sizeof(u64));
8698 for (i = 0; i < n; i++)
8700 /* zero out counters that only exist in rtnl_link_stats64 */
8701 memset((char *)stats64 + n * sizeof(u64), 0,
8702 sizeof(*stats64) - n * sizeof(u64));
8705 EXPORT_SYMBOL(netdev_stats_to_stats64);
8708 * dev_get_stats - get network device statistics
8709 * @dev: device to get statistics from
8710 * @storage: place to store stats
8712 * Get network statistics from device. Return @storage.
8713 * The device driver may provide its own method by setting
8714 * dev->netdev_ops->get_stats64 or dev->netdev_ops->get_stats;
8715 * otherwise the internal statistics structure is used.
8717 struct rtnl_link_stats64 *dev_get_stats(struct net_device *dev,
8718 struct rtnl_link_stats64 *storage)
8720 const struct net_device_ops *ops = dev->netdev_ops;
8722 if (ops->ndo_get_stats64) {
8723 memset(storage, 0, sizeof(*storage));
8724 ops->ndo_get_stats64(dev, storage);
8725 } else if (ops->ndo_get_stats) {
8726 netdev_stats_to_stats64(storage, ops->ndo_get_stats(dev));
8728 netdev_stats_to_stats64(storage, &dev->stats);
8730 storage->rx_dropped += (unsigned long)atomic_long_read(&dev->rx_dropped);
8731 storage->tx_dropped += (unsigned long)atomic_long_read(&dev->tx_dropped);
8732 storage->rx_nohandler += (unsigned long)atomic_long_read(&dev->rx_nohandler);
8735 EXPORT_SYMBOL(dev_get_stats);
8737 struct netdev_queue *dev_ingress_queue_create(struct net_device *dev)
8739 struct netdev_queue *queue = dev_ingress_queue(dev);
8741 #ifdef CONFIG_NET_CLS_ACT
8744 queue = kzalloc(sizeof(*queue), GFP_KERNEL);
8747 netdev_init_one_queue(dev, queue, NULL);
8748 RCU_INIT_POINTER(queue->qdisc, &noop_qdisc);
8749 queue->qdisc_sleeping = &noop_qdisc;
8750 rcu_assign_pointer(dev->ingress_queue, queue);
8755 static const struct ethtool_ops default_ethtool_ops;
8757 void netdev_set_default_ethtool_ops(struct net_device *dev,
8758 const struct ethtool_ops *ops)
8760 if (dev->ethtool_ops == &default_ethtool_ops)
8761 dev->ethtool_ops = ops;
8763 EXPORT_SYMBOL_GPL(netdev_set_default_ethtool_ops);
8765 void netdev_freemem(struct net_device *dev)
8767 char *addr = (char *)dev - dev->padded;
8773 * alloc_netdev_mqs - allocate network device
8774 * @sizeof_priv: size of private data to allocate space for
8775 * @name: device name format string
8776 * @name_assign_type: origin of device name
8777 * @setup: callback to initialize device
8778 * @txqs: the number of TX subqueues to allocate
8779 * @rxqs: the number of RX subqueues to allocate
8781 * Allocates a struct net_device with private data area for driver use
8782 * and performs basic initialization. Also allocates subqueue structs
8783 * for each queue on the device.
8785 struct net_device *alloc_netdev_mqs(int sizeof_priv, const char *name,
8786 unsigned char name_assign_type,
8787 void (*setup)(struct net_device *),
8788 unsigned int txqs, unsigned int rxqs)
8790 struct net_device *dev;
8791 unsigned int alloc_size;
8792 struct net_device *p;
8794 BUG_ON(strlen(name) >= sizeof(dev->name));
8797 pr_err("alloc_netdev: Unable to allocate device with zero queues\n");
8802 pr_err("alloc_netdev: Unable to allocate device with zero RX queues\n");
8806 alloc_size = sizeof(struct net_device);
8808 /* ensure 32-byte alignment of private area */
8809 alloc_size = ALIGN(alloc_size, NETDEV_ALIGN);
8810 alloc_size += sizeof_priv;
8812 /* ensure 32-byte alignment of whole construct */
8813 alloc_size += NETDEV_ALIGN - 1;
8815 p = kvzalloc(alloc_size, GFP_KERNEL | __GFP_RETRY_MAYFAIL);
8819 dev = PTR_ALIGN(p, NETDEV_ALIGN);
8820 dev->padded = (char *)dev - (char *)p;
8822 dev->pcpu_refcnt = alloc_percpu(int);
8823 if (!dev->pcpu_refcnt)
8826 if (dev_addr_init(dev))
8832 dev_net_set(dev, &init_net);
8834 dev->gso_max_size = GSO_MAX_SIZE;
8835 dev->gso_max_segs = GSO_MAX_SEGS;
8837 INIT_LIST_HEAD(&dev->napi_list);
8838 INIT_LIST_HEAD(&dev->unreg_list);
8839 INIT_LIST_HEAD(&dev->close_list);
8840 INIT_LIST_HEAD(&dev->link_watch_list);
8841 INIT_LIST_HEAD(&dev->adj_list.upper);
8842 INIT_LIST_HEAD(&dev->adj_list.lower);
8843 INIT_LIST_HEAD(&dev->ptype_all);
8844 INIT_LIST_HEAD(&dev->ptype_specific);
8845 #ifdef CONFIG_NET_SCHED
8846 hash_init(dev->qdisc_hash);
8848 dev->priv_flags = IFF_XMIT_DST_RELEASE | IFF_XMIT_DST_RELEASE_PERM;
8851 if (!dev->tx_queue_len) {
8852 dev->priv_flags |= IFF_NO_QUEUE;
8853 dev->tx_queue_len = DEFAULT_TX_QUEUE_LEN;
8856 dev->num_tx_queues = txqs;
8857 dev->real_num_tx_queues = txqs;
8858 if (netif_alloc_netdev_queues(dev))
8861 dev->num_rx_queues = rxqs;
8862 dev->real_num_rx_queues = rxqs;
8863 if (netif_alloc_rx_queues(dev))
8866 strcpy(dev->name, name);
8867 dev->name_assign_type = name_assign_type;
8868 dev->group = INIT_NETDEV_GROUP;
8869 if (!dev->ethtool_ops)
8870 dev->ethtool_ops = &default_ethtool_ops;
8872 nf_hook_ingress_init(dev);
8881 free_percpu(dev->pcpu_refcnt);
8883 netdev_freemem(dev);
8886 EXPORT_SYMBOL(alloc_netdev_mqs);
8889 * free_netdev - free network device
8892 * This function does the last stage of destroying an allocated device
8893 * interface. The reference to the device object is released. If this
8894 * is the last reference then it will be freed.Must be called in process
8897 void free_netdev(struct net_device *dev)
8899 struct napi_struct *p, *n;
8902 netif_free_tx_queues(dev);
8903 netif_free_rx_queues(dev);
8905 kfree(rcu_dereference_protected(dev->ingress_queue, 1));
8907 /* Flush device addresses */
8908 dev_addr_flush(dev);
8910 list_for_each_entry_safe(p, n, &dev->napi_list, dev_list)
8913 free_percpu(dev->pcpu_refcnt);
8914 dev->pcpu_refcnt = NULL;
8916 /* Compatibility with error handling in drivers */
8917 if (dev->reg_state == NETREG_UNINITIALIZED) {
8918 netdev_freemem(dev);
8922 BUG_ON(dev->reg_state != NETREG_UNREGISTERED);
8923 dev->reg_state = NETREG_RELEASED;
8925 /* will free via device release */
8926 put_device(&dev->dev);
8928 EXPORT_SYMBOL(free_netdev);
8931 * synchronize_net - Synchronize with packet receive processing
8933 * Wait for packets currently being received to be done.
8934 * Does not block later packets from starting.
8936 void synchronize_net(void)
8939 if (rtnl_is_locked())
8940 synchronize_rcu_expedited();
8944 EXPORT_SYMBOL(synchronize_net);
8947 * unregister_netdevice_queue - remove device from the kernel
8951 * This function shuts down a device interface and removes it
8952 * from the kernel tables.
8953 * If head not NULL, device is queued to be unregistered later.
8955 * Callers must hold the rtnl semaphore. You may want
8956 * unregister_netdev() instead of this.
8959 void unregister_netdevice_queue(struct net_device *dev, struct list_head *head)
8964 list_move_tail(&dev->unreg_list, head);
8966 rollback_registered(dev);
8967 /* Finish processing unregister after unlock */
8971 EXPORT_SYMBOL(unregister_netdevice_queue);
8974 * unregister_netdevice_many - unregister many devices
8975 * @head: list of devices
8977 * Note: As most callers use a stack allocated list_head,
8978 * we force a list_del() to make sure stack wont be corrupted later.
8980 void unregister_netdevice_many(struct list_head *head)
8982 struct net_device *dev;
8984 if (!list_empty(head)) {
8985 rollback_registered_many(head);
8986 list_for_each_entry(dev, head, unreg_list)
8991 EXPORT_SYMBOL(unregister_netdevice_many);
8994 * unregister_netdev - remove device from the kernel
8997 * This function shuts down a device interface and removes it
8998 * from the kernel tables.
9000 * This is just a wrapper for unregister_netdevice that takes
9001 * the rtnl semaphore. In general you want to use this and not
9002 * unregister_netdevice.
9004 void unregister_netdev(struct net_device *dev)
9007 unregister_netdevice(dev);
9010 EXPORT_SYMBOL(unregister_netdev);
9013 * dev_change_net_namespace - move device to different nethost namespace
9015 * @net: network namespace
9016 * @pat: If not NULL name pattern to try if the current device name
9017 * is already taken in the destination network namespace.
9019 * This function shuts down a device interface and moves it
9020 * to a new network namespace. On success 0 is returned, on
9021 * a failure a netagive errno code is returned.
9023 * Callers must hold the rtnl semaphore.
9026 int dev_change_net_namespace(struct net_device *dev, struct net *net, const char *pat)
9028 int err, new_nsid, new_ifindex;
9032 /* Don't allow namespace local devices to be moved. */
9034 if (dev->features & NETIF_F_NETNS_LOCAL)
9037 /* Ensure the device has been registrered */
9038 if (dev->reg_state != NETREG_REGISTERED)
9041 /* Get out if there is nothing todo */
9043 if (net_eq(dev_net(dev), net))
9046 /* Pick the destination device name, and ensure
9047 * we can use it in the destination network namespace.
9050 if (__dev_get_by_name(net, dev->name)) {
9051 /* We get here if we can't use the current device name */
9054 err = dev_get_valid_name(net, dev, pat);
9060 * And now a mini version of register_netdevice unregister_netdevice.
9063 /* If device is running close it first. */
9066 /* And unlink it from device chain */
9067 unlist_netdevice(dev);
9071 /* Shutdown queueing discipline. */
9074 /* Notify protocols, that we are about to destroy
9075 * this device. They should clean all the things.
9077 * Note that dev->reg_state stays at NETREG_REGISTERED.
9078 * This is wanted because this way 8021q and macvlan know
9079 * the device is just moving and can keep their slaves up.
9081 call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
9084 new_nsid = peernet2id_alloc(dev_net(dev), net);
9085 /* If there is an ifindex conflict assign a new one */
9086 if (__dev_get_by_index(net, dev->ifindex))
9087 new_ifindex = dev_new_index(net);
9089 new_ifindex = dev->ifindex;
9091 rtmsg_ifinfo_newnet(RTM_DELLINK, dev, ~0U, GFP_KERNEL, &new_nsid,
9095 * Flush the unicast and multicast chains
9100 /* Send a netdev-removed uevent to the old namespace */
9101 kobject_uevent(&dev->dev.kobj, KOBJ_REMOVE);
9102 netdev_adjacent_del_links(dev);
9104 /* Actually switch the network namespace */
9105 dev_net_set(dev, net);
9106 dev->ifindex = new_ifindex;
9108 /* Send a netdev-add uevent to the new namespace */
9109 kobject_uevent(&dev->dev.kobj, KOBJ_ADD);
9110 netdev_adjacent_add_links(dev);
9112 /* Fixup kobjects */
9113 err = device_rename(&dev->dev, dev->name);
9116 /* Add the device back in the hashes */
9117 list_netdevice(dev);
9119 /* Notify protocols, that a new device appeared. */
9120 call_netdevice_notifiers(NETDEV_REGISTER, dev);
9123 * Prevent userspace races by waiting until the network
9124 * device is fully setup before sending notifications.
9126 rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U, GFP_KERNEL);
9133 EXPORT_SYMBOL_GPL(dev_change_net_namespace);
9135 static int dev_cpu_dead(unsigned int oldcpu)
9137 struct sk_buff **list_skb;
9138 struct sk_buff *skb;
9140 struct softnet_data *sd, *oldsd, *remsd = NULL;
9142 local_irq_disable();
9143 cpu = smp_processor_id();
9144 sd = &per_cpu(softnet_data, cpu);
9145 oldsd = &per_cpu(softnet_data, oldcpu);
9147 /* Find end of our completion_queue. */
9148 list_skb = &sd->completion_queue;
9150 list_skb = &(*list_skb)->next;
9151 /* Append completion queue from offline CPU. */
9152 *list_skb = oldsd->completion_queue;
9153 oldsd->completion_queue = NULL;
9155 /* Append output queue from offline CPU. */
9156 if (oldsd->output_queue) {
9157 *sd->output_queue_tailp = oldsd->output_queue;
9158 sd->output_queue_tailp = oldsd->output_queue_tailp;
9159 oldsd->output_queue = NULL;
9160 oldsd->output_queue_tailp = &oldsd->output_queue;
9162 /* Append NAPI poll list from offline CPU, with one exception :
9163 * process_backlog() must be called by cpu owning percpu backlog.
9164 * We properly handle process_queue & input_pkt_queue later.
9166 while (!list_empty(&oldsd->poll_list)) {
9167 struct napi_struct *napi = list_first_entry(&oldsd->poll_list,
9171 list_del_init(&napi->poll_list);
9172 if (napi->poll == process_backlog)
9175 ____napi_schedule(sd, napi);
9178 raise_softirq_irqoff(NET_TX_SOFTIRQ);
9182 remsd = oldsd->rps_ipi_list;
9183 oldsd->rps_ipi_list = NULL;
9185 /* send out pending IPI's on offline CPU */
9186 net_rps_send_ipi(remsd);
9188 /* Process offline CPU's input_pkt_queue */
9189 while ((skb = __skb_dequeue(&oldsd->process_queue))) {
9191 input_queue_head_incr(oldsd);
9193 while ((skb = skb_dequeue(&oldsd->input_pkt_queue))) {
9195 input_queue_head_incr(oldsd);
9202 * netdev_increment_features - increment feature set by one
9203 * @all: current feature set
9204 * @one: new feature set
9205 * @mask: mask feature set
9207 * Computes a new feature set after adding a device with feature set
9208 * @one to the master device with current feature set @all. Will not
9209 * enable anything that is off in @mask. Returns the new feature set.
9211 netdev_features_t netdev_increment_features(netdev_features_t all,
9212 netdev_features_t one, netdev_features_t mask)
9214 if (mask & NETIF_F_HW_CSUM)
9215 mask |= NETIF_F_CSUM_MASK;
9216 mask |= NETIF_F_VLAN_CHALLENGED;
9218 all |= one & (NETIF_F_ONE_FOR_ALL | NETIF_F_CSUM_MASK) & mask;
9219 all &= one | ~NETIF_F_ALL_FOR_ALL;
9221 /* If one device supports hw checksumming, set for all. */
9222 if (all & NETIF_F_HW_CSUM)
9223 all &= ~(NETIF_F_CSUM_MASK & ~NETIF_F_HW_CSUM);
9227 EXPORT_SYMBOL(netdev_increment_features);
9229 static struct hlist_head * __net_init netdev_create_hash(void)
9232 struct hlist_head *hash;
9234 hash = kmalloc_array(NETDEV_HASHENTRIES, sizeof(*hash), GFP_KERNEL);
9236 for (i = 0; i < NETDEV_HASHENTRIES; i++)
9237 INIT_HLIST_HEAD(&hash[i]);
9242 /* Initialize per network namespace state */
9243 static int __net_init netdev_init(struct net *net)
9245 if (net != &init_net)
9246 INIT_LIST_HEAD(&net->dev_base_head);
9248 net->dev_name_head = netdev_create_hash();
9249 if (net->dev_name_head == NULL)
9252 net->dev_index_head = netdev_create_hash();
9253 if (net->dev_index_head == NULL)
9259 kfree(net->dev_name_head);
9265 * netdev_drivername - network driver for the device
9266 * @dev: network device
9268 * Determine network driver for device.
9270 const char *netdev_drivername(const struct net_device *dev)
9272 const struct device_driver *driver;
9273 const struct device *parent;
9274 const char *empty = "";
9276 parent = dev->dev.parent;
9280 driver = parent->driver;
9281 if (driver && driver->name)
9282 return driver->name;
9286 static void __netdev_printk(const char *level, const struct net_device *dev,
9287 struct va_format *vaf)
9289 if (dev && dev->dev.parent) {
9290 dev_printk_emit(level[1] - '0',
9293 dev_driver_string(dev->dev.parent),
9294 dev_name(dev->dev.parent),
9295 netdev_name(dev), netdev_reg_state(dev),
9298 printk("%s%s%s: %pV",
9299 level, netdev_name(dev), netdev_reg_state(dev), vaf);
9301 printk("%s(NULL net_device): %pV", level, vaf);
9305 void netdev_printk(const char *level, const struct net_device *dev,
9306 const char *format, ...)
9308 struct va_format vaf;
9311 va_start(args, format);
9316 __netdev_printk(level, dev, &vaf);
9320 EXPORT_SYMBOL(netdev_printk);
9322 #define define_netdev_printk_level(func, level) \
9323 void func(const struct net_device *dev, const char *fmt, ...) \
9325 struct va_format vaf; \
9328 va_start(args, fmt); \
9333 __netdev_printk(level, dev, &vaf); \
9337 EXPORT_SYMBOL(func);
9339 define_netdev_printk_level(netdev_emerg, KERN_EMERG);
9340 define_netdev_printk_level(netdev_alert, KERN_ALERT);
9341 define_netdev_printk_level(netdev_crit, KERN_CRIT);
9342 define_netdev_printk_level(netdev_err, KERN_ERR);
9343 define_netdev_printk_level(netdev_warn, KERN_WARNING);
9344 define_netdev_printk_level(netdev_notice, KERN_NOTICE);
9345 define_netdev_printk_level(netdev_info, KERN_INFO);
9347 static void __net_exit netdev_exit(struct net *net)
9349 kfree(net->dev_name_head);
9350 kfree(net->dev_index_head);
9351 if (net != &init_net)
9352 WARN_ON_ONCE(!list_empty(&net->dev_base_head));
9355 static struct pernet_operations __net_initdata netdev_net_ops = {
9356 .init = netdev_init,
9357 .exit = netdev_exit,
9360 static void __net_exit default_device_exit(struct net *net)
9362 struct net_device *dev, *aux;
9364 * Push all migratable network devices back to the
9365 * initial network namespace
9368 for_each_netdev_safe(net, dev, aux) {
9370 char fb_name[IFNAMSIZ];
9372 /* Ignore unmoveable devices (i.e. loopback) */
9373 if (dev->features & NETIF_F_NETNS_LOCAL)
9376 /* Leave virtual devices for the generic cleanup */
9377 if (dev->rtnl_link_ops)
9380 /* Push remaining network devices to init_net */
9381 snprintf(fb_name, IFNAMSIZ, "dev%d", dev->ifindex);
9382 err = dev_change_net_namespace(dev, &init_net, fb_name);
9384 pr_emerg("%s: failed to move %s to init_net: %d\n",
9385 __func__, dev->name, err);
9392 static void __net_exit rtnl_lock_unregistering(struct list_head *net_list)
9394 /* Return with the rtnl_lock held when there are no network
9395 * devices unregistering in any network namespace in net_list.
9399 DEFINE_WAIT_FUNC(wait, woken_wake_function);
9401 add_wait_queue(&netdev_unregistering_wq, &wait);
9403 unregistering = false;
9405 list_for_each_entry(net, net_list, exit_list) {
9406 if (net->dev_unreg_count > 0) {
9407 unregistering = true;
9415 wait_woken(&wait, TASK_UNINTERRUPTIBLE, MAX_SCHEDULE_TIMEOUT);
9417 remove_wait_queue(&netdev_unregistering_wq, &wait);
9420 static void __net_exit default_device_exit_batch(struct list_head *net_list)
9422 /* At exit all network devices most be removed from a network
9423 * namespace. Do this in the reverse order of registration.
9424 * Do this across as many network namespaces as possible to
9425 * improve batching efficiency.
9427 struct net_device *dev;
9429 LIST_HEAD(dev_kill_list);
9431 /* To prevent network device cleanup code from dereferencing
9432 * loopback devices or network devices that have been freed
9433 * wait here for all pending unregistrations to complete,
9434 * before unregistring the loopback device and allowing the
9435 * network namespace be freed.
9437 * The netdev todo list containing all network devices
9438 * unregistrations that happen in default_device_exit_batch
9439 * will run in the rtnl_unlock() at the end of
9440 * default_device_exit_batch.
9442 rtnl_lock_unregistering(net_list);
9443 list_for_each_entry(net, net_list, exit_list) {
9444 for_each_netdev_reverse(net, dev) {
9445 if (dev->rtnl_link_ops && dev->rtnl_link_ops->dellink)
9446 dev->rtnl_link_ops->dellink(dev, &dev_kill_list);
9448 unregister_netdevice_queue(dev, &dev_kill_list);
9451 unregister_netdevice_many(&dev_kill_list);
9455 static struct pernet_operations __net_initdata default_device_ops = {
9456 .exit = default_device_exit,
9457 .exit_batch = default_device_exit_batch,
9461 * Initialize the DEV module. At boot time this walks the device list and
9462 * unhooks any devices that fail to initialise (normally hardware not
9463 * present) and leaves us with a valid list of present and active devices.
9468 * This is called single threaded during boot, so no need
9469 * to take the rtnl semaphore.
9471 static int __init net_dev_init(void)
9473 int i, rc = -ENOMEM;
9475 BUG_ON(!dev_boot_phase);
9477 if (dev_proc_init())
9480 if (netdev_kobject_init())
9483 INIT_LIST_HEAD(&ptype_all);
9484 for (i = 0; i < PTYPE_HASH_SIZE; i++)
9485 INIT_LIST_HEAD(&ptype_base[i]);
9487 INIT_LIST_HEAD(&offload_base);
9489 if (register_pernet_subsys(&netdev_net_ops))
9493 * Initialise the packet receive queues.
9496 for_each_possible_cpu(i) {
9497 struct work_struct *flush = per_cpu_ptr(&flush_works, i);
9498 struct softnet_data *sd = &per_cpu(softnet_data, i);
9500 INIT_WORK(flush, flush_backlog);
9502 skb_queue_head_init(&sd->input_pkt_queue);
9503 skb_queue_head_init(&sd->process_queue);
9504 #ifdef CONFIG_XFRM_OFFLOAD
9505 skb_queue_head_init(&sd->xfrm_backlog);
9507 INIT_LIST_HEAD(&sd->poll_list);
9508 sd->output_queue_tailp = &sd->output_queue;
9510 sd->csd.func = rps_trigger_softirq;
9515 sd->backlog.poll = process_backlog;
9516 sd->backlog.weight = weight_p;
9521 /* The loopback device is special if any other network devices
9522 * is present in a network namespace the loopback device must
9523 * be present. Since we now dynamically allocate and free the
9524 * loopback device ensure this invariant is maintained by
9525 * keeping the loopback device as the first device on the
9526 * list of network devices. Ensuring the loopback devices
9527 * is the first device that appears and the last network device
9530 if (register_pernet_device(&loopback_net_ops))
9533 if (register_pernet_device(&default_device_ops))
9536 open_softirq(NET_TX_SOFTIRQ, net_tx_action);
9537 open_softirq(NET_RX_SOFTIRQ, net_rx_action);
9539 rc = cpuhp_setup_state_nocalls(CPUHP_NET_DEV_DEAD, "net/dev:dead",
9540 NULL, dev_cpu_dead);
9547 subsys_initcall(net_dev_init);