/* * NET3 Protocol independent device support routines. * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version * 2 of the License, or (at your option) any later version. * * Derived from the non IP parts of dev.c 1.0.19 * Authors: Ross Biro * Fred N. van Kempen, * Mark Evans, * * Additional Authors: * Florian la Roche * Alan Cox * David Hinds * Alexey Kuznetsov * Adam Sulmicki * Pekka Riikonen * * Changes: * D.J. Barrow : Fixed bug where dev->refcnt gets set * to 2 if register_netdev gets called * before net_dev_init & also removed a * few lines of code in the process. * Alan Cox : device private ioctl copies fields back. * Alan Cox : Transmit queue code does relevant * stunts to keep the queue safe. * Alan Cox : Fixed double lock. * Alan Cox : Fixed promisc NULL pointer trap * ???????? : Support the full private ioctl range * Alan Cox : Moved ioctl permission check into * drivers * Tim Kordas : SIOCADDMULTI/SIOCDELMULTI * Alan Cox : 100 backlog just doesn't cut it when * you start doing multicast video 8) * Alan Cox : Rewrote net_bh and list manager. * Alan Cox : Fix ETH_P_ALL echoback lengths. * Alan Cox : Took out transmit every packet pass * Saved a few bytes in the ioctl handler * Alan Cox : Network driver sets packet type before * calling netif_rx. Saves a function * call a packet. * Alan Cox : Hashed net_bh() * Richard Kooijman: Timestamp fixes. * Alan Cox : Wrong field in SIOCGIFDSTADDR * Alan Cox : Device lock protection. * Alan Cox : Fixed nasty side effect of device close * changes. * Rudi Cilibrasi : Pass the right thing to * set_mac_address() * Dave Miller : 32bit quantity for the device lock to * make it work out on a Sparc. * Bjorn Ekwall : Added KERNELD hack. * Alan Cox : Cleaned up the backlog initialise. * Craig Metz : SIOCGIFCONF fix if space for under * 1 device. * Thomas Bogendoerfer : Return ENODEV for dev_open, if there * is no device open function. * Andi Kleen : Fix error reporting for SIOCGIFCONF * Michael Chastain : Fix signed/unsigned for SIOCGIFCONF * Cyrus Durgin : Cleaned for KMOD * Adam Sulmicki : Bug Fix : Network Device Unload * A network device unload needs to purge * the backlog queue. * Paul Rusty Russell : SIOCSIFNAME * Pekka Riikonen : Netdev boot-time settings code * Andrew Morton : Make unregister_netdevice wait * indefinitely on dev->refcnt * J Hadi Salim : - Backlog queue sampling * - netif_rx() feedback */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "net-sysfs.h" /* Instead of increasing this, you should create a hash table. */ #define MAX_GRO_SKBS 8 /* This should be increased if a protocol with a bigger head is added. */ #define GRO_MAX_HEAD (MAX_HEADER + 128) static DEFINE_SPINLOCK(ptype_lock); static DEFINE_SPINLOCK(offload_lock); struct list_head ptype_base[PTYPE_HASH_SIZE] __read_mostly; struct list_head ptype_all __read_mostly; /* Taps */ static struct list_head offload_base __read_mostly; static int netif_rx_internal(struct sk_buff *skb); static int call_netdevice_notifiers_info(unsigned long val, struct net_device *dev, struct netdev_notifier_info *info); static struct napi_struct *napi_by_id(unsigned int napi_id); /* * The @dev_base_head list is protected by @dev_base_lock and the rtnl * semaphore. * * Pure readers hold dev_base_lock for reading, or rcu_read_lock() * * Writers must hold the rtnl semaphore while they loop through the * dev_base_head list, and hold dev_base_lock for writing when they do the * actual updates. This allows pure readers to access the list even * while a writer is preparing to update it. * * To put it another way, dev_base_lock is held for writing only to * protect against pure readers; the rtnl semaphore provides the * protection against other writers. * * See, for example usages, register_netdevice() and * unregister_netdevice(), which must be called with the rtnl * semaphore held. */ DEFINE_RWLOCK(dev_base_lock); EXPORT_SYMBOL(dev_base_lock); /* protects napi_hash addition/deletion and napi_gen_id */ static DEFINE_SPINLOCK(napi_hash_lock); static unsigned int napi_gen_id = NR_CPUS; static DEFINE_READ_MOSTLY_HASHTABLE(napi_hash, 8); static DECLARE_RWSEM(devnet_rename_sem); static inline void dev_base_seq_inc(struct net *net) { while (++net->dev_base_seq == 0) ; } static inline struct hlist_head *dev_name_hash(struct net *net, const char *name) { unsigned int hash = full_name_hash(net, name, strnlen(name, IFNAMSIZ)); return &net->dev_name_head[hash_32(hash, NETDEV_HASHBITS)]; } static inline struct hlist_head *dev_index_hash(struct net *net, int ifindex) { return &net->dev_index_head[ifindex & (NETDEV_HASHENTRIES - 1)]; } static inline void rps_lock(struct softnet_data *sd) { #ifdef CONFIG_RPS spin_lock(&sd->input_pkt_queue.lock); #endif } static inline void rps_unlock(struct softnet_data *sd) { #ifdef CONFIG_RPS spin_unlock(&sd->input_pkt_queue.lock); #endif } /* Device list insertion */ static void list_netdevice(struct net_device *dev) { struct net *net = dev_net(dev); ASSERT_RTNL(); write_lock_bh(&dev_base_lock); list_add_tail_rcu(&dev->dev_list, &net->dev_base_head); hlist_add_head_rcu(&dev->name_hlist, dev_name_hash(net, dev->name)); hlist_add_head_rcu(&dev->index_hlist, dev_index_hash(net, dev->ifindex)); write_unlock_bh(&dev_base_lock); dev_base_seq_inc(net); } /* Device list removal * caller must respect a RCU grace period before freeing/reusing dev */ static void unlist_netdevice(struct net_device *dev) { ASSERT_RTNL(); /* Unlink dev from the device chain */ write_lock_bh(&dev_base_lock); list_del_rcu(&dev->dev_list); hlist_del_rcu(&dev->name_hlist); hlist_del_rcu(&dev->index_hlist); write_unlock_bh(&dev_base_lock); dev_base_seq_inc(dev_net(dev)); } /* * Our notifier list */ static RAW_NOTIFIER_HEAD(netdev_chain); /* * Device drivers call our routines to queue packets here. We empty the * queue in the local softnet handler. */ DEFINE_PER_CPU_ALIGNED(struct softnet_data, softnet_data); EXPORT_PER_CPU_SYMBOL(softnet_data); #ifdef CONFIG_LOCKDEP /* * register_netdevice() inits txq->_xmit_lock and sets lockdep class * according to dev->type */ static const unsigned short netdev_lock_type[] = { ARPHRD_NETROM, ARPHRD_ETHER, ARPHRD_EETHER, ARPHRD_AX25, ARPHRD_PRONET, ARPHRD_CHAOS, ARPHRD_IEEE802, ARPHRD_ARCNET, ARPHRD_APPLETLK, ARPHRD_DLCI, ARPHRD_ATM, ARPHRD_METRICOM, ARPHRD_IEEE1394, ARPHRD_EUI64, ARPHRD_INFINIBAND, ARPHRD_SLIP, ARPHRD_CSLIP, ARPHRD_SLIP6, ARPHRD_CSLIP6, ARPHRD_RSRVD, ARPHRD_ADAPT, ARPHRD_ROSE, ARPHRD_X25, ARPHRD_HWX25, ARPHRD_PPP, ARPHRD_CISCO, ARPHRD_LAPB, ARPHRD_DDCMP, ARPHRD_RAWHDLC, ARPHRD_TUNNEL, ARPHRD_TUNNEL6, ARPHRD_FRAD, ARPHRD_SKIP, ARPHRD_LOOPBACK, ARPHRD_LOCALTLK, ARPHRD_FDDI, ARPHRD_BIF, ARPHRD_SIT, ARPHRD_IPDDP, ARPHRD_IPGRE, ARPHRD_PIMREG, ARPHRD_HIPPI, ARPHRD_ASH, ARPHRD_ECONET, ARPHRD_IRDA, ARPHRD_FCPP, ARPHRD_FCAL, ARPHRD_FCPL, ARPHRD_FCFABRIC, ARPHRD_IEEE80211, ARPHRD_IEEE80211_PRISM, ARPHRD_IEEE80211_RADIOTAP, ARPHRD_PHONET, ARPHRD_PHONET_PIPE, ARPHRD_IEEE802154, ARPHRD_VOID, ARPHRD_NONE}; static const char *const netdev_lock_name[] = { "_xmit_NETROM", "_xmit_ETHER", "_xmit_EETHER", "_xmit_AX25", "_xmit_PRONET", "_xmit_CHAOS", "_xmit_IEEE802", "_xmit_ARCNET", "_xmit_APPLETLK", "_xmit_DLCI", "_xmit_ATM", "_xmit_METRICOM", "_xmit_IEEE1394", "_xmit_EUI64", "_xmit_INFINIBAND", "_xmit_SLIP", "_xmit_CSLIP", "_xmit_SLIP6", "_xmit_CSLIP6", "_xmit_RSRVD", "_xmit_ADAPT", "_xmit_ROSE", "_xmit_X25", "_xmit_HWX25", "_xmit_PPP", "_xmit_CISCO", "_xmit_LAPB", "_xmit_DDCMP", "_xmit_RAWHDLC", "_xmit_TUNNEL", "_xmit_TUNNEL6", "_xmit_FRAD", "_xmit_SKIP", "_xmit_LOOPBACK", "_xmit_LOCALTLK", "_xmit_FDDI", "_xmit_BIF", "_xmit_SIT", "_xmit_IPDDP", "_xmit_IPGRE", "_xmit_PIMREG", "_xmit_HIPPI", "_xmit_ASH", "_xmit_ECONET", "_xmit_IRDA", "_xmit_FCPP", "_xmit_FCAL", "_xmit_FCPL", "_xmit_FCFABRIC", "_xmit_IEEE80211", "_xmit_IEEE80211_PRISM", "_xmit_IEEE80211_RADIOTAP", "_xmit_PHONET", "_xmit_PHONET_PIPE", "_xmit_IEEE802154", "_xmit_VOID", "_xmit_NONE"}; static struct lock_class_key netdev_xmit_lock_key[ARRAY_SIZE(netdev_lock_type)]; static struct lock_class_key netdev_addr_lock_key[ARRAY_SIZE(netdev_lock_type)]; static inline unsigned short netdev_lock_pos(unsigned short dev_type) { int i; for (i = 0; i < ARRAY_SIZE(netdev_lock_type); i++) if (netdev_lock_type[i] == dev_type) return i; /* the last key is used by default */ return ARRAY_SIZE(netdev_lock_type) - 1; } static inline void netdev_set_xmit_lockdep_class(spinlock_t *lock, unsigned short dev_type) { int i; i = netdev_lock_pos(dev_type); lockdep_set_class_and_name(lock, &netdev_xmit_lock_key[i], netdev_lock_name[i]); } static inline void netdev_set_addr_lockdep_class(struct net_device *dev) { int i; i = netdev_lock_pos(dev->type); lockdep_set_class_and_name(&dev->addr_list_lock, &netdev_addr_lock_key[i], netdev_lock_name[i]); } #else static inline void netdev_set_xmit_lockdep_class(spinlock_t *lock, unsigned short dev_type) { } static inline void netdev_set_addr_lockdep_class(struct net_device *dev) { } #endif /******************************************************************************* * * Protocol management and registration routines * *******************************************************************************/ /* * Add a protocol ID to the list. Now that the input handler is * smarter we can dispense with all the messy stuff that used to be * here. * * BEWARE!!! Protocol handlers, mangling input packets, * MUST BE last in hash buckets and checking protocol handlers * MUST start from promiscuous ptype_all chain in net_bh. * It is true now, do not change it. * Explanation follows: if protocol handler, mangling packet, will * be the first on list, it is not able to sense, that packet * is cloned and should be copied-on-write, so that it will * change it and subsequent readers will get broken packet. * --ANK (980803) */ static inline struct list_head *ptype_head(const struct packet_type *pt) { if (pt->type == htons(ETH_P_ALL)) return pt->dev ? &pt->dev->ptype_all : &ptype_all; else return pt->dev ? &pt->dev->ptype_specific : &ptype_base[ntohs(pt->type) & PTYPE_HASH_MASK]; } /** * dev_add_pack - add packet handler * @pt: packet type declaration * * Add a protocol handler to the networking stack. The passed &packet_type * is linked into kernel lists and may not be freed until it has been * removed from the kernel lists. * * This call does not sleep therefore it can not * guarantee all CPU's that are in middle of receiving packets * will see the new packet type (until the next received packet). */ void dev_add_pack(struct packet_type *pt) { struct list_head *head = ptype_head(pt); spin_lock(&ptype_lock); list_add_rcu(&pt->list, head); spin_unlock(&ptype_lock); } EXPORT_SYMBOL(dev_add_pack); /** * __dev_remove_pack - remove packet handler * @pt: packet type declaration * * Remove a protocol handler that was previously added to the kernel * protocol handlers by dev_add_pack(). The passed &packet_type is removed * from the kernel lists and can be freed or reused once this function * returns. * * The packet type might still be in use by receivers * and must not be freed until after all the CPU's have gone * through a quiescent state. */ void __dev_remove_pack(struct packet_type *pt) { struct list_head *head = ptype_head(pt); struct packet_type *pt1; spin_lock(&ptype_lock); list_for_each_entry(pt1, head, list) { if (pt == pt1) { list_del_rcu(&pt->list); goto out; } } pr_warn("dev_remove_pack: %p not found\n", pt); out: spin_unlock(&ptype_lock); } EXPORT_SYMBOL(__dev_remove_pack); /** * dev_remove_pack - remove packet handler * @pt: packet type declaration * * Remove a protocol handler that was previously added to the kernel * protocol handlers by dev_add_pack(). The passed &packet_type is removed * from the kernel lists and can be freed or reused once this function * returns. * * This call sleeps to guarantee that no CPU is looking at the packet * type after return. */ void dev_remove_pack(struct packet_type *pt) { __dev_remove_pack(pt); synchronize_net(); } EXPORT_SYMBOL(dev_remove_pack); /** * dev_add_offload - register offload handlers * @po: protocol offload declaration * * Add protocol offload handlers to the networking stack. The passed * &proto_offload is linked into kernel lists and may not be freed until * it has been removed from the kernel lists. * * This call does not sleep therefore it can not * guarantee all CPU's that are in middle of receiving packets * will see the new offload handlers (until the next received packet). */ void dev_add_offload(struct packet_offload *po) { struct packet_offload *elem; spin_lock(&offload_lock); list_for_each_entry(elem, &offload_base, list) { if (po->priority < elem->priority) break; } list_add_rcu(&po->list, elem->list.prev); spin_unlock(&offload_lock); } EXPORT_SYMBOL(dev_add_offload); /** * __dev_remove_offload - remove offload handler * @po: packet offload declaration * * Remove a protocol offload handler that was previously added to the * kernel offload handlers by dev_add_offload(). The passed &offload_type * is removed from the kernel lists and can be freed or reused once this * function returns. * * The packet type might still be in use by receivers * and must not be freed until after all the CPU's have gone * through a quiescent state. */ static void __dev_remove_offload(struct packet_offload *po) { struct list_head *head = &offload_base; struct packet_offload *po1; spin_lock(&offload_lock); list_for_each_entry(po1, head, list) { if (po == po1) { list_del_rcu(&po->list); goto out; } } pr_warn("dev_remove_offload: %p not found\n", po); out: spin_unlock(&offload_lock); } /** * dev_remove_offload - remove packet offload handler * @po: packet offload declaration * * Remove a packet offload handler that was previously added to the kernel * offload handlers by dev_add_offload(). The passed &offload_type is * removed from the kernel lists and can be freed or reused once this * function returns. * * This call sleeps to guarantee that no CPU is looking at the packet * type after return. */ void dev_remove_offload(struct packet_offload *po) { __dev_remove_offload(po); synchronize_net(); } EXPORT_SYMBOL(dev_remove_offload); /****************************************************************************** * * Device Boot-time Settings Routines * ******************************************************************************/ /* Boot time configuration table */ static struct netdev_boot_setup dev_boot_setup[NETDEV_BOOT_SETUP_MAX]; /** * netdev_boot_setup_add - add new setup entry * @name: name of the device * @map: configured settings for the device * * Adds new setup entry to the dev_boot_setup list. The function * returns 0 on error and 1 on success. This is a generic routine to * all netdevices. */ static int netdev_boot_setup_add(char *name, struct ifmap *map) { struct netdev_boot_setup *s; int i; s = dev_boot_setup; for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++) { if (s[i].name[0] == '\0' || s[i].name[0] == ' ') { memset(s[i].name, 0, sizeof(s[i].name)); strlcpy(s[i].name, name, IFNAMSIZ); memcpy(&s[i].map, map, sizeof(s[i].map)); break; } } return i >= NETDEV_BOOT_SETUP_MAX ? 0 : 1; } /** * netdev_boot_setup_check - check boot time settings * @dev: the netdevice * * Check boot time settings for the device. * The found settings are set for the device to be used * later in the device probing. * Returns 0 if no settings found, 1 if they are. */ int netdev_boot_setup_check(struct net_device *dev) { struct netdev_boot_setup *s = dev_boot_setup; int i; for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++) { if (s[i].name[0] != '\0' && s[i].name[0] != ' ' && !strcmp(dev->name, s[i].name)) { dev->irq = s[i].map.irq; dev->base_addr = s[i].map.base_addr; dev->mem_start = s[i].map.mem_start; dev->mem_end = s[i].map.mem_end; return 1; } } return 0; } EXPORT_SYMBOL(netdev_boot_setup_check); /** * netdev_boot_base - get address from boot time settings * @prefix: prefix for network device * @unit: id for network device * * Check boot time settings for the base address of device. * The found settings are set for the device to be used * later in the device probing. * Returns 0 if no settings found. */ unsigned long netdev_boot_base(const char *prefix, int unit) { const struct netdev_boot_setup *s = dev_boot_setup; char name[IFNAMSIZ]; int i; sprintf(name, "%s%d", prefix, unit); /* * If device already registered then return base of 1 * to indicate not to probe for this interface */ if (__dev_get_by_name(&init_net, name)) return 1; for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++) if (!strcmp(name, s[i].name)) return s[i].map.base_addr; return 0; } /* * Saves at boot time configured settings for any netdevice. */ int __init netdev_boot_setup(char *str) { int ints[5]; struct ifmap map; str = get_options(str, ARRAY_SIZE(ints), ints); if (!str || !*str) return 0; /* Save settings */ memset(&map, 0, sizeof(map)); if (ints[0] > 0) map.irq = ints[1]; if (ints[0] > 1) map.base_addr = ints[2]; if (ints[0] > 2) map.mem_start = ints[3]; if (ints[0] > 3) map.mem_end = ints[4]; /* Add new entry to the list */ return netdev_boot_setup_add(str, &map); } __setup("netdev=", netdev_boot_setup); /******************************************************************************* * * Device Interface Subroutines * *******************************************************************************/ /** * dev_get_iflink - get 'iflink' value of a interface * @dev: targeted interface * * Indicates the ifindex the interface is linked to. * Physical interfaces have the same 'ifindex' and 'iflink' values. */ int dev_get_iflink(const struct net_device *dev) { if (dev->netdev_ops && dev->netdev_ops->ndo_get_iflink) return dev->netdev_ops->ndo_get_iflink(dev); return dev->ifindex; } EXPORT_SYMBOL(dev_get_iflink); /** * dev_fill_metadata_dst - Retrieve tunnel egress information. * @dev: targeted interface * @skb: The packet. * * For better visibility of tunnel traffic OVS needs to retrieve * egress tunnel information for a packet. Following API allows * user to get this info. */ int dev_fill_metadata_dst(struct net_device *dev, struct sk_buff *skb) { struct ip_tunnel_info *info; if (!dev->netdev_ops || !dev->netdev_ops->ndo_fill_metadata_dst) return -EINVAL; info = skb_tunnel_info_unclone(skb); if (!info) return -ENOMEM; if (unlikely(!(info->mode & IP_TUNNEL_INFO_TX))) return -EINVAL; return dev->netdev_ops->ndo_fill_metadata_dst(dev, skb); } EXPORT_SYMBOL_GPL(dev_fill_metadata_dst); /** * __dev_get_by_name - find a device by its name * @net: the applicable net namespace * @name: name to find * * Find an interface by name. Must be called under RTNL semaphore * or @dev_base_lock. If the name is found a pointer to the device * is returned. If the name is not found then %NULL is returned. The * reference counters are not incremented so the caller must be * careful with locks. */ struct net_device *__dev_get_by_name(struct net *net, const char *name) { struct net_device *dev; struct hlist_head *head = dev_name_hash(net, name); hlist_for_each_entry(dev, head, name_hlist) if (!strncmp(dev->name, name, IFNAMSIZ)) return dev; return NULL; } EXPORT_SYMBOL(__dev_get_by_name); /** * dev_get_by_name_rcu - find a device by its name * @net: the applicable net namespace * @name: name to find * * Find an interface by name. * If the name is found a pointer to the device is returned. * If the name is not found then %NULL is returned. * The reference counters are not incremented so the caller must be * careful with locks. The caller must hold RCU lock. */ struct net_device *dev_get_by_name_rcu(struct net *net, const char *name) { struct net_device *dev; struct hlist_head *head = dev_name_hash(net, name); hlist_for_each_entry_rcu(dev, head, name_hlist) if (!strncmp(dev->name, name, IFNAMSIZ)) return dev; return NULL; } EXPORT_SYMBOL(dev_get_by_name_rcu); /** * dev_get_by_name - find a device by its name * @net: the applicable net namespace * @name: name to find * * Find an interface by name. This can be called from any * context and does its own locking. The returned handle has * the usage count incremented and the caller must use dev_put() to * release it when it is no longer needed. %NULL is returned if no * matching device is found. */ struct net_device *dev_get_by_name(struct net *net, const char *name) { struct net_device *dev; rcu_read_lock(); dev = dev_get_by_name_rcu(net, name); if (dev) dev_hold(dev); rcu_read_unlock(); return dev; } EXPORT_SYMBOL(dev_get_by_name); /** * __dev_get_by_index - find a device by its ifindex * @net: the applicable net namespace * @ifindex: index of device * * Search for an interface by index. Returns %NULL if the device * is not found or a pointer to the device. The device has not * had its reference counter increased so the caller must be careful * about locking. The caller must hold either the RTNL semaphore * or @dev_base_lock. */ struct net_device *__dev_get_by_index(struct net *net, int ifindex) { struct net_device *dev; struct hlist_head *head = dev_index_hash(net, ifindex); hlist_for_each_entry(dev, head, index_hlist) if (dev->ifindex == ifindex) return dev; return NULL; } EXPORT_SYMBOL(__dev_get_by_index); /** * dev_get_by_index_rcu - find a device by its ifindex * @net: the applicable net namespace * @ifindex: index of device * * Search for an interface by index. Returns %NULL if the device * is not found or a pointer to the device. The device has not * had its reference counter increased so the caller must be careful * about locking. The caller must hold RCU lock. */ struct net_device *dev_get_by_index_rcu(struct net *net, int ifindex) { struct net_device *dev; struct hlist_head *head = dev_index_hash(net, ifindex); hlist_for_each_entry_rcu(dev, head, index_hlist) if (dev->ifindex == ifindex) return dev; return NULL; } EXPORT_SYMBOL(dev_get_by_index_rcu); /** * dev_get_by_index - find a device by its ifindex * @net: the applicable net namespace * @ifindex: index of device * * Search for an interface by index. Returns NULL if the device * is not found or a pointer to the device. The device returned has * had a reference added and the pointer is safe until the user calls * dev_put to indicate they have finished with it. */ struct net_device *dev_get_by_index(struct net *net, int ifindex) { struct net_device *dev; rcu_read_lock(); dev = dev_get_by_index_rcu(net, ifindex); if (dev) dev_hold(dev); rcu_read_unlock(); return dev; } EXPORT_SYMBOL(dev_get_by_index); /** * dev_get_by_napi_id - find a device by napi_id * @napi_id: ID of the NAPI struct * * Search for an interface by NAPI ID. Returns %NULL if the device * is not found or a pointer to the device. The device has not had * its reference counter increased so the caller must be careful * about locking. The caller must hold RCU lock. */ struct net_device *dev_get_by_napi_id(unsigned int napi_id) { struct napi_struct *napi; WARN_ON_ONCE(!rcu_read_lock_held()); if (napi_id < ((unsigned int)(NR_CPUS + 1))) return NULL; napi = napi_by_id(napi_id); return napi ? napi->dev : NULL; } EXPORT_SYMBOL(dev_get_by_napi_id); /** * netdev_get_name - get a netdevice name, knowing its ifindex. * @net: network namespace * @name: a pointer to the buffer where the name will be stored. * @ifindex: the ifindex of the interface to get the name from. */ int netdev_get_name(struct net *net, char *name, int ifindex) { struct net_device *dev; int ret; down_read(&devnet_rename_sem); rcu_read_lock(); dev = dev_get_by_index_rcu(net, ifindex); if (!dev) { ret = -ENODEV; goto out; } strcpy(name, dev->name); ret = 0; out: rcu_read_unlock(); up_read(&devnet_rename_sem); return ret; } /** * dev_getbyhwaddr_rcu - find a device by its hardware address * @net: the applicable net namespace * @type: media type of device * @ha: hardware address * * Search for an interface by MAC address. Returns NULL if the device * is not found or a pointer to the device. * The caller must hold RCU or RTNL. * The returned device has not had its ref count increased * and the caller must therefore be careful about locking * */ struct net_device *dev_getbyhwaddr_rcu(struct net *net, unsigned short type, const char *ha) { struct net_device *dev; for_each_netdev_rcu(net, dev) if (dev->type == type && !memcmp(dev->dev_addr, ha, dev->addr_len)) return dev; return NULL; } EXPORT_SYMBOL(dev_getbyhwaddr_rcu); struct net_device *__dev_getfirstbyhwtype(struct net *net, unsigned short type) { struct net_device *dev; ASSERT_RTNL(); for_each_netdev(net, dev) if (dev->type == type) return dev; return NULL; } EXPORT_SYMBOL(__dev_getfirstbyhwtype); struct net_device *dev_getfirstbyhwtype(struct net *net, unsigned short type) { struct net_device *dev, *ret = NULL; rcu_read_lock(); for_each_netdev_rcu(net, dev) if (dev->type == type) { dev_hold(dev); ret = dev; break; } rcu_read_unlock(); return ret; } EXPORT_SYMBOL(dev_getfirstbyhwtype); /** * __dev_get_by_flags - find any device with given flags * @net: the applicable net namespace * @if_flags: IFF_* values * @mask: bitmask of bits in if_flags to check * * Search for any interface with the given flags. Returns NULL if a device * is not found or a pointer to the device. Must be called inside * rtnl_lock(), and result refcount is unchanged. */ struct net_device *__dev_get_by_flags(struct net *net, unsigned short if_flags, unsigned short mask) { struct net_device *dev, *ret; ASSERT_RTNL(); ret = NULL; for_each_netdev(net, dev) { if (((dev->flags ^ if_flags) & mask) == 0) { ret = dev; break; } } return ret; } EXPORT_SYMBOL(__dev_get_by_flags); /** * dev_valid_name - check if name is okay for network device * @name: name string * * Network device names need to be valid file names to * to allow sysfs to work. We also disallow any kind of * whitespace. */ bool dev_valid_name(const char *name) { if (*name == '\0') return false; if (strnlen(name, IFNAMSIZ) == IFNAMSIZ) return false; if (!strcmp(name, ".") || !strcmp(name, "..")) return false; while (*name) { if (*name == '/' || *name == ':' || isspace(*name)) return false; name++; } return true; } EXPORT_SYMBOL(dev_valid_name); /** * __dev_alloc_name - allocate a name for a device * @net: network namespace to allocate the device name in * @name: name format string * @buf: scratch buffer and result name string * * Passed a format string - eg "lt%d" it will try and find a suitable * id. It scans list of devices to build up a free map, then chooses * the first empty slot. The caller must hold the dev_base or rtnl lock * while allocating the name and adding the device in order to avoid * duplicates. * Limited to bits_per_byte * page size devices (ie 32K on most platforms). * Returns the number of the unit assigned or a negative errno code. */ static int __dev_alloc_name(struct net *net, const char *name, char *buf) { int i = 0; const char *p; const int max_netdevices = 8*PAGE_SIZE; unsigned long *inuse; struct net_device *d; p = strnchr(name, IFNAMSIZ-1, '%'); if (p) { /* * Verify the string as this thing may have come from * the user. There must be either one "%d" and no other "%" * characters. */ if (p[1] != 'd' || strchr(p + 2, '%')) return -EINVAL; /* Use one page as a bit array of possible slots */ inuse = (unsigned long *) get_zeroed_page(GFP_ATOMIC); if (!inuse) return -ENOMEM; for_each_netdev(net, d) { if (!sscanf(d->name, name, &i)) continue; if (i < 0 || i >= max_netdevices) continue; /* avoid cases where sscanf is not exact inverse of printf */ snprintf(buf, IFNAMSIZ, name, i); if (!strncmp(buf, d->name, IFNAMSIZ)) set_bit(i, inuse); } i = find_first_zero_bit(inuse, max_netdevices); free_page((unsigned long) inuse); } if (buf != name) snprintf(buf, IFNAMSIZ, name, i); if (!__dev_get_by_name(net, buf)) return i; /* It is possible to run out of possible slots * when the name is long and there isn't enough space left * for the digits, or if all bits are used. */ return -ENFILE; } /** * dev_alloc_name - allocate a name for a device * @dev: device * @name: name format string * * Passed a format string - eg "lt%d" it will try and find a suitable * id. It scans list of devices to build up a free map, then chooses * the first empty slot. The caller must hold the dev_base or rtnl lock * while allocating the name and adding the device in order to avoid * duplicates. * Limited to bits_per_byte * page size devices (ie 32K on most platforms). * Returns the number of the unit assigned or a negative errno code. */ int dev_alloc_name(struct net_device *dev, const char *name) { char buf[IFNAMSIZ]; struct net *net; int ret; BUG_ON(!dev_net(dev)); net = dev_net(dev); ret = __dev_alloc_name(net, name, buf); if (ret >= 0) strlcpy(dev->name, buf, IFNAMSIZ); return ret; } EXPORT_SYMBOL(dev_alloc_name); static int dev_alloc_name_ns(struct net *net, struct net_device *dev, const char *name) { char buf[IFNAMSIZ]; int ret; ret = __dev_alloc_name(net, name, buf); if (ret >= 0) strlcpy(dev->name, buf, IFNAMSIZ); return ret; } int dev_get_valid_name(struct net *net, struct net_device *dev, const char *name) { BUG_ON(!net); if (!dev_valid_name(name)) return -EINVAL; if (strchr(name, '%')) return dev_alloc_name_ns(net, dev, name); else if (__dev_get_by_name(net, name)) return -EEXIST; else if (dev->name != name) strlcpy(dev->name, name, IFNAMSIZ); return 0; } EXPORT_SYMBOL(dev_get_valid_name); /** * dev_change_name - change name of a device * @dev: device * @newname: name (or format string) must be at least IFNAMSIZ * * Change name of a device, can pass format strings "eth%d". * for wildcarding. */ int dev_change_name(struct net_device *dev, const char *newname) { unsigned char old_assign_type; char oldname[IFNAMSIZ]; int err = 0; int ret; struct net *net; ASSERT_RTNL(); BUG_ON(!dev_net(dev)); net = dev_net(dev); if (dev->flags & IFF_UP) return -EBUSY; down_write(&devnet_rename_sem); if (strncmp(newname, dev->name, IFNAMSIZ) == 0) { up_write(&devnet_rename_sem); return 0; } memcpy(oldname, dev->name, IFNAMSIZ); err = dev_get_valid_name(net, dev, newname); if (err < 0) { up_write(&devnet_rename_sem); return err; } if (oldname[0] && !strchr(oldname, '%')) netdev_info(dev, "renamed from %s\n", oldname); old_assign_type = dev->name_assign_type; dev->name_assign_type = NET_NAME_RENAMED; rollback: ret = device_rename(&dev->dev, dev->name); if (ret) { memcpy(dev->name, oldname, IFNAMSIZ); dev->name_assign_type = old_assign_type; up_write(&devnet_rename_sem); return ret; } up_write(&devnet_rename_sem); netdev_adjacent_rename_links(dev, oldname); write_lock_bh(&dev_base_lock); hlist_del_rcu(&dev->name_hlist); write_unlock_bh(&dev_base_lock); synchronize_rcu(); write_lock_bh(&dev_base_lock); hlist_add_head_rcu(&dev->name_hlist, dev_name_hash(net, dev->name)); write_unlock_bh(&dev_base_lock); ret = call_netdevice_notifiers(NETDEV_CHANGENAME, dev); ret = notifier_to_errno(ret); if (ret) { /* err >= 0 after dev_alloc_name() or stores the first errno */ if (err >= 0) { err = ret; down_write(&devnet_rename_sem); memcpy(dev->name, oldname, IFNAMSIZ); memcpy(oldname, newname, IFNAMSIZ); dev->name_assign_type = old_assign_type; old_assign_type = NET_NAME_RENAMED; goto rollback; } else { pr_err("%s: name change rollback failed: %d\n", dev->name, ret); } } return err; } /** * dev_set_alias - change ifalias of a device * @dev: device * @alias: name up to IFALIASZ * @len: limit of bytes to copy from info * * Set ifalias for a device, */ int dev_set_alias(struct net_device *dev, const char *alias, size_t len) { char *new_ifalias; ASSERT_RTNL(); if (len >= IFALIASZ) return -EINVAL; if (!len) { kfree(dev->ifalias); dev->ifalias = NULL; return 0; } new_ifalias = krealloc(dev->ifalias, len + 1, GFP_KERNEL); if (!new_ifalias) return -ENOMEM; dev->ifalias = new_ifalias; memcpy(dev->ifalias, alias, len); dev->ifalias[len] = 0; return len; } /** * netdev_features_change - device changes features * @dev: device to cause notification * * Called to indicate a device has changed features. */ void netdev_features_change(struct net_device *dev) { call_netdevice_notifiers(NETDEV_FEAT_CHANGE, dev); } EXPORT_SYMBOL(netdev_features_change); /** * netdev_state_change - device changes state * @dev: device to cause notification * * Called to indicate a device has changed state. This function calls * the notifier chains for netdev_chain and sends a NEWLINK message * to the routing socket. */ void netdev_state_change(struct net_device *dev) { if (dev->flags & IFF_UP) { struct netdev_notifier_change_info change_info; change_info.flags_changed = 0; call_netdevice_notifiers_info(NETDEV_CHANGE, dev, &change_info.info); rtmsg_ifinfo(RTM_NEWLINK, dev, 0, GFP_KERNEL); } } EXPORT_SYMBOL(netdev_state_change); /** * netdev_notify_peers - notify network peers about existence of @dev * @dev: network device * * Generate traffic such that interested network peers are aware of * @dev, such as by generating a gratuitous ARP. This may be used when * a device wants to inform the rest of the network about some sort of * reconfiguration such as a failover event or virtual machine * migration. */ void netdev_notify_peers(struct net_device *dev) { rtnl_lock(); call_netdevice_notifiers(NETDEV_NOTIFY_PEERS, dev); call_netdevice_notifiers(NETDEV_RESEND_IGMP, dev); rtnl_unlock(); } EXPORT_SYMBOL(netdev_notify_peers); static int __dev_open(struct net_device *dev) { const struct net_device_ops *ops = dev->netdev_ops; int ret; ASSERT_RTNL(); if (!netif_device_present(dev)) return -ENODEV; /* Block netpoll from trying to do any rx path servicing. * If we don't do this there is a chance ndo_poll_controller * or ndo_poll may be running while we open the device */ netpoll_poll_disable(dev); ret = call_netdevice_notifiers(NETDEV_PRE_UP, dev); ret = notifier_to_errno(ret); if (ret) return ret; set_bit(__LINK_STATE_START, &dev->state); if (ops->ndo_validate_addr) ret = ops->ndo_validate_addr(dev); if (!ret && ops->ndo_open) ret = ops->ndo_open(dev); netpoll_poll_enable(dev); if (ret) clear_bit(__LINK_STATE_START, &dev->state); else { dev->flags |= IFF_UP; dev_set_rx_mode(dev); dev_activate(dev); add_device_randomness(dev->dev_addr, dev->addr_len); } return ret; } /** * dev_open - prepare an interface for use. * @dev: device to open * * Takes a device from down to up state. The device's private open * function is invoked and then the multicast lists are loaded. Finally * the device is moved into the up state and a %NETDEV_UP message is * sent to the netdev notifier chain. * * Calling this function on an active interface is a nop. On a failure * a negative errno code is returned. */ int dev_open(struct net_device *dev) { int ret; if (dev->flags & IFF_UP) return 0; ret = __dev_open(dev); if (ret < 0) return ret; rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP|IFF_RUNNING, GFP_KERNEL); call_netdevice_notifiers(NETDEV_UP, dev); return ret; } EXPORT_SYMBOL(dev_open); static int __dev_close_many(struct list_head *head) { struct net_device *dev; ASSERT_RTNL(); might_sleep(); list_for_each_entry(dev, head, close_list) { /* Temporarily disable netpoll until the interface is down */ netpoll_poll_disable(dev); call_netdevice_notifiers(NETDEV_GOING_DOWN, dev); clear_bit(__LINK_STATE_START, &dev->state); /* Synchronize to scheduled poll. We cannot touch poll list, it * can be even on different cpu. So just clear netif_running(). * * dev->stop() will invoke napi_disable() on all of it's * napi_struct instances on this device. */ smp_mb__after_atomic(); /* Commit netif_running(). */ } dev_deactivate_many(head); list_for_each_entry(dev, head, close_list) { const struct net_device_ops *ops = dev->netdev_ops; /* * Call the device specific close. This cannot fail. * Only if device is UP * * We allow it to be called even after a DETACH hot-plug * event. */ if (ops->ndo_stop) ops->ndo_stop(dev); dev->flags &= ~IFF_UP; netpoll_poll_enable(dev); } return 0; } static int __dev_close(struct net_device *dev) { int retval; LIST_HEAD(single); list_add(&dev->close_list, &single); retval = __dev_close_many(&single); list_del(&single); return retval; } int dev_close_many(struct list_head *head, bool unlink) { struct net_device *dev, *tmp; /* Remove the devices that don't need to be closed */ list_for_each_entry_safe(dev, tmp, head, close_list) if (!(dev->flags & IFF_UP)) list_del_init(&dev->close_list); __dev_close_many(head); list_for_each_entry_safe(dev, tmp, head, close_list) { rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP|IFF_RUNNING, GFP_KERNEL); call_netdevice_notifiers(NETDEV_DOWN, dev); if (unlink) list_del_init(&dev->close_list); } return 0; } EXPORT_SYMBOL(dev_close_many); /** * dev_close - shutdown an interface. * @dev: device to shutdown * * This function moves an active device into down state. A * %NETDEV_GOING_DOWN is sent to the netdev notifier chain. The device * is then deactivated and finally a %NETDEV_DOWN is sent to the notifier * chain. */ int dev_close(struct net_device *dev) { if (dev->flags & IFF_UP) { LIST_HEAD(single); list_add(&dev->close_list, &single); dev_close_many(&single, true); list_del(&single); } return 0; } EXPORT_SYMBOL(dev_close); /** * dev_disable_lro - disable Large Receive Offload on a device * @dev: device * * Disable Large Receive Offload (LRO) on a net device. Must be * called under RTNL. This is needed if received packets may be * forwarded to another interface. */ void dev_disable_lro(struct net_device *dev) { struct net_device *lower_dev; struct list_head *iter; dev->wanted_features &= ~NETIF_F_LRO; netdev_update_features(dev); if (unlikely(dev->features & NETIF_F_LRO)) netdev_WARN(dev, "failed to disable LRO!\n"); netdev_for_each_lower_dev(dev, lower_dev, iter) dev_disable_lro(lower_dev); } EXPORT_SYMBOL(dev_disable_lro); static int call_netdevice_notifier(struct notifier_block *nb, unsigned long val, struct net_device *dev) { struct netdev_notifier_info info; netdev_notifier_info_init(&info, dev); return nb->notifier_call(nb, val, &info); } static int dev_boot_phase = 1; /** * register_netdevice_notifier - register a network notifier block * @nb: notifier * * Register a notifier to be called when network device events occur. * The notifier passed is linked into the kernel structures and must * not be reused until it has been unregistered. A negative errno code * is returned on a failure. * * When registered all registration and up events are replayed * to the new notifier to allow device to have a race free * view of the network device list. */ int register_netdevice_notifier(struct notifier_block *nb) { struct net_device *dev; struct net_device *last; struct net *net; int err; rtnl_lock(); err = raw_notifier_chain_register(&netdev_chain, nb); if (err) goto unlock; if (dev_boot_phase) goto unlock; for_each_net(net) { for_each_netdev(net, dev) { err = call_netdevice_notifier(nb, NETDEV_REGISTER, dev); err = notifier_to_errno(err); if (err) goto rollback; if (!(dev->flags & IFF_UP)) continue; call_netdevice_notifier(nb, NETDEV_UP, dev); } } unlock: rtnl_unlock(); return err; rollback: last = dev; for_each_net(net) { for_each_netdev(net, dev) { if (dev == last) goto outroll; if (dev->flags & IFF_UP) { call_netdevice_notifier(nb, NETDEV_GOING_DOWN, dev); call_netdevice_notifier(nb, NETDEV_DOWN, dev); } call_netdevice_notifier(nb, NETDEV_UNREGISTER, dev); } } outroll: raw_notifier_chain_unregister(&netdev_chain, nb); goto unlock; } EXPORT_SYMBOL(register_netdevice_notifier); /** * unregister_netdevice_notifier - unregister a network notifier block * @nb: notifier * * Unregister a notifier previously registered by * register_netdevice_notifier(). The notifier is unlinked into the * kernel structures and may then be reused. A negative errno code * is returned on a failure. * * After unregistering unregister and down device events are synthesized * for all devices on the device list to the removed notifier to remove * the need for special case cleanup code. */ int unregister_netdevice_notifier(struct notifier_block *nb) { struct net_device *dev; struct net *net; int err; rtnl_lock(); err = raw_notifier_chain_unregister(&netdev_chain, nb); if (err) goto unlock; for_each_net(net) { for_each_netdev(net, dev) { if (dev->flags & IFF_UP) { call_netdevice_notifier(nb, NETDEV_GOING_DOWN, dev); call_netdevice_notifier(nb, NETDEV_DOWN, dev); } call_netdevice_notifier(nb, NETDEV_UNREGISTER, dev); } } unlock: rtnl_unlock(); return err; } EXPORT_SYMBOL(unregister_netdevice_notifier); /** * call_netdevice_notifiers_info - call all network notifier blocks * @val: value passed unmodified to notifier function * @dev: net_device pointer passed unmodified to notifier function * @info: notifier information data * * Call all network notifier blocks. Parameters and return value * are as for raw_notifier_call_chain(). */ static int call_netdevice_notifiers_info(unsigned long val, struct net_device *dev, struct netdev_notifier_info *info) { ASSERT_RTNL(); netdev_notifier_info_init(info, dev); return raw_notifier_call_chain(&netdev_chain, val, info); } /** * call_netdevice_notifiers - call all network notifier blocks * @val: value passed unmodified to notifier function * @dev: net_device pointer passed unmodified to notifier function * * Call all network notifier blocks. Parameters and return value * are as for raw_notifier_call_chain(). */ int call_netdevice_notifiers(unsigned long val, struct net_device *dev) { struct netdev_notifier_info info; return call_netdevice_notifiers_info(val, dev, &info); } EXPORT_SYMBOL(call_netdevice_notifiers); /** * call_netdevice_notifiers_mtu - call all network notifier blocks * @val: value passed unmodified to notifier function * @dev: net_device pointer passed unmodified to notifier function * @arg: additional u32 argument passed to the notifier function * * Call all network notifier blocks. Parameters and return value * are as for raw_notifier_call_chain(). */ static int call_netdevice_notifiers_mtu(unsigned long val, struct net_device *dev, u32 arg) { struct netdev_notifier_info_ext info = { .info.dev = dev, .ext.mtu = arg, }; BUILD_BUG_ON(offsetof(struct netdev_notifier_info_ext, info) != 0); return call_netdevice_notifiers_info(val, dev, &info.info); } #ifdef CONFIG_NET_INGRESS static struct static_key ingress_needed __read_mostly; void net_inc_ingress_queue(void) { static_key_slow_inc(&ingress_needed); } EXPORT_SYMBOL_GPL(net_inc_ingress_queue); void net_dec_ingress_queue(void) { static_key_slow_dec(&ingress_needed); } EXPORT_SYMBOL_GPL(net_dec_ingress_queue); #endif #ifdef CONFIG_NET_EGRESS static struct static_key egress_needed __read_mostly; void net_inc_egress_queue(void) { static_key_slow_inc(&egress_needed); } EXPORT_SYMBOL_GPL(net_inc_egress_queue); void net_dec_egress_queue(void) { static_key_slow_dec(&egress_needed); } EXPORT_SYMBOL_GPL(net_dec_egress_queue); #endif static struct static_key netstamp_needed __read_mostly; #ifdef HAVE_JUMP_LABEL static atomic_t netstamp_needed_deferred; static atomic_t netstamp_wanted; static void netstamp_clear(struct work_struct *work) { int deferred = atomic_xchg(&netstamp_needed_deferred, 0); int wanted; wanted = atomic_add_return(deferred, &netstamp_wanted); if (wanted > 0) static_key_enable(&netstamp_needed); else static_key_disable(&netstamp_needed); } static DECLARE_WORK(netstamp_work, netstamp_clear); #endif void net_enable_timestamp(void) { #ifdef HAVE_JUMP_LABEL int wanted; while (1) { wanted = atomic_read(&netstamp_wanted); if (wanted <= 0) break; if (atomic_cmpxchg(&netstamp_wanted, wanted, wanted + 1) == wanted) return; } atomic_inc(&netstamp_needed_deferred); schedule_work(&netstamp_work); #else static_key_slow_inc(&netstamp_needed); #endif } EXPORT_SYMBOL(net_enable_timestamp); void net_disable_timestamp(void) { #ifdef HAVE_JUMP_LABEL int wanted; while (1) { wanted = atomic_read(&netstamp_wanted); if (wanted <= 1) break; if (atomic_cmpxchg(&netstamp_wanted, wanted, wanted - 1) == wanted) return; } atomic_dec(&netstamp_needed_deferred); schedule_work(&netstamp_work); #else static_key_slow_dec(&netstamp_needed); #endif } EXPORT_SYMBOL(net_disable_timestamp); static inline void net_timestamp_set(struct sk_buff *skb) { skb->tstamp.tv64 = 0; if (static_key_false(&netstamp_needed)) __net_timestamp(skb); } #define net_timestamp_check(COND, SKB) \ if (static_key_false(&netstamp_needed)) { \ if ((COND) && !(SKB)->tstamp.tv64) \ __net_timestamp(SKB); \ } \ bool is_skb_forwardable(const struct net_device *dev, const struct sk_buff *skb) { unsigned int len; if (!(dev->flags & IFF_UP)) return false; len = dev->mtu + dev->hard_header_len + VLAN_HLEN; if (skb->len <= len) return true; /* if TSO is enabled, we don't care about the length as the packet * could be forwarded without being segmented before */ if (skb_is_gso(skb)) return true; return false; } EXPORT_SYMBOL_GPL(is_skb_forwardable); int __dev_forward_skb(struct net_device *dev, struct sk_buff *skb) { int ret = ____dev_forward_skb(dev, skb); if (likely(!ret)) { skb->protocol = eth_type_trans(skb, dev); skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN); } return ret; } EXPORT_SYMBOL_GPL(__dev_forward_skb); /** * dev_forward_skb - loopback an skb to another netif * * @dev: destination network device * @skb: buffer to forward * * return values: * NET_RX_SUCCESS (no congestion) * NET_RX_DROP (packet was dropped, but freed) * * dev_forward_skb can be used for injecting an skb from the * start_xmit function of one device into the receive queue * of another device. * * The receiving device may be in another namespace, so * we have to clear all information in the skb that could * impact namespace isolation. */ int dev_forward_skb(struct net_device *dev, struct sk_buff *skb) { return __dev_forward_skb(dev, skb) ?: netif_rx_internal(skb); } EXPORT_SYMBOL_GPL(dev_forward_skb); static inline int deliver_skb(struct sk_buff *skb, struct packet_type *pt_prev, struct net_device *orig_dev) { if (unlikely(skb_orphan_frags_rx(skb, GFP_ATOMIC))) return -ENOMEM; atomic_inc(&skb->users); return pt_prev->func(skb, skb->dev, pt_prev, orig_dev); } static inline void deliver_ptype_list_skb(struct sk_buff *skb, struct packet_type **pt, struct net_device *orig_dev, __be16 type, struct list_head *ptype_list) { struct packet_type *ptype, *pt_prev = *pt; list_for_each_entry_rcu(ptype, ptype_list, list) { if (ptype->type != type) continue; if (pt_prev) deliver_skb(skb, pt_prev, orig_dev); pt_prev = ptype; } *pt = pt_prev; } static inline bool skb_loop_sk(struct packet_type *ptype, struct sk_buff *skb) { if (!ptype->af_packet_priv || !skb->sk) return false; if (ptype->id_match) return ptype->id_match(ptype, skb->sk); else if ((struct sock *)ptype->af_packet_priv == skb->sk) return true; return false; } /* * Support routine. Sends outgoing frames to any network * taps currently in use. */ void dev_queue_xmit_nit(struct sk_buff *skb, struct net_device *dev) { struct packet_type *ptype; struct sk_buff *skb2 = NULL; struct packet_type *pt_prev = NULL; struct list_head *ptype_list = &ptype_all; rcu_read_lock(); again: list_for_each_entry_rcu(ptype, ptype_list, list) { /* Never send packets back to the socket * they originated from - MvS (miquels@drinkel.ow.org) */ if (skb_loop_sk(ptype, skb)) continue; if (pt_prev) { deliver_skb(skb2, pt_prev, skb->dev); pt_prev = ptype; continue; } /* need to clone skb, done only once */ skb2 = skb_clone(skb, GFP_ATOMIC); if (!skb2) goto out_unlock; net_timestamp_set(skb2); /* skb->nh should be correctly * set by sender, so that the second statement is * just protection against buggy protocols. */ skb_reset_mac_header(skb2); if (skb_network_header(skb2) < skb2->data || skb_network_header(skb2) > skb_tail_pointer(skb2)) { net_crit_ratelimited("protocol %04x is buggy, dev %s\n", ntohs(skb2->protocol), dev->name); skb_reset_network_header(skb2); } skb2->transport_header = skb2->network_header; skb2->pkt_type = PACKET_OUTGOING; pt_prev = ptype; } if (ptype_list == &ptype_all) { ptype_list = &dev->ptype_all; goto again; } out_unlock: if (pt_prev) pt_prev->func(skb2, skb->dev, pt_prev, skb->dev); rcu_read_unlock(); } EXPORT_SYMBOL_GPL(dev_queue_xmit_nit); /** * netif_setup_tc - Handle tc mappings on real_num_tx_queues change * @dev: Network device * @txq: number of queues available * * If real_num_tx_queues is changed the tc mappings may no longer be * valid. To resolve this verify the tc mapping remains valid and if * not NULL the mapping. With no priorities mapping to this * offset/count pair it will no longer be used. In the worst case TC0 * is invalid nothing can be done so disable priority mappings. If is * expected that drivers will fix this mapping if they can before * calling netif_set_real_num_tx_queues. */ static void netif_setup_tc(struct net_device *dev, unsigned int txq) { int i; struct netdev_tc_txq *tc = &dev->tc_to_txq[0]; /* If TC0 is invalidated disable TC mapping */ if (tc->offset + tc->count > txq) { pr_warn("Number of in use tx queues changed invalidating tc mappings. Priority traffic classification disabled!\n"); dev->num_tc = 0; return; } /* Invalidated prio to tc mappings set to TC0 */ for (i = 1; i < TC_BITMASK + 1; i++) { int q = netdev_get_prio_tc_map(dev, i); tc = &dev->tc_to_txq[q]; if (tc->offset + tc->count > txq) { pr_warn("Number of in use tx queues changed. Priority %i to tc mapping %i is no longer valid. Setting map to 0\n", i, q); netdev_set_prio_tc_map(dev, i, 0); } } } #ifdef CONFIG_XPS static DEFINE_MUTEX(xps_map_mutex); #define xmap_dereference(P) \ rcu_dereference_protected((P), lockdep_is_held(&xps_map_mutex)) static struct xps_map *remove_xps_queue(struct xps_dev_maps *dev_maps, int cpu, u16 index) { struct xps_map *map = NULL; int pos; if (dev_maps) map = xmap_dereference(dev_maps->cpu_map[cpu]); for (pos = 0; map && pos < map->len; pos++) { if (map->queues[pos] == index) { if (map->len > 1) { map->queues[pos] = map->queues[--map->len]; } else { RCU_INIT_POINTER(dev_maps->cpu_map[cpu], NULL); kfree_rcu(map, rcu); map = NULL; } break; } } return map; } static void netif_reset_xps_queues_gt(struct net_device *dev, u16 index) { struct xps_dev_maps *dev_maps; int cpu, i; bool active = false; mutex_lock(&xps_map_mutex); dev_maps = xmap_dereference(dev->xps_maps); if (!dev_maps) goto out_no_maps; for_each_possible_cpu(cpu) { for (i = index; i < dev->num_tx_queues; i++) { if (!remove_xps_queue(dev_maps, cpu, i)) break; } if (i == dev->num_tx_queues) active = true; } if (!active) { RCU_INIT_POINTER(dev->xps_maps, NULL); kfree_rcu(dev_maps, rcu); } for (i = index; i < dev->num_tx_queues; i++) netdev_queue_numa_node_write(netdev_get_tx_queue(dev, i), NUMA_NO_NODE); out_no_maps: mutex_unlock(&xps_map_mutex); } static struct xps_map *expand_xps_map(struct xps_map *map, int cpu, u16 index) { struct xps_map *new_map; int alloc_len = XPS_MIN_MAP_ALLOC; int i, pos; for (pos = 0; map && pos < map->len; pos++) { if (map->queues[pos] != index) continue; return map; } /* Need to add queue to this CPU's existing map */ if (map) { if (pos < map->alloc_len) return map; alloc_len = map->alloc_len * 2; } /* Need to allocate new map to store queue on this CPU's map */ new_map = kzalloc_node(XPS_MAP_SIZE(alloc_len), GFP_KERNEL, cpu_to_node(cpu)); if (!new_map) return NULL; for (i = 0; i < pos; i++) new_map->queues[i] = map->queues[i]; new_map->alloc_len = alloc_len; new_map->len = pos; return new_map; } int netif_set_xps_queue(struct net_device *dev, const struct cpumask *mask, u16 index) { struct xps_dev_maps *dev_maps, *new_dev_maps = NULL; struct xps_map *map, *new_map; int maps_sz = max_t(unsigned int, XPS_DEV_MAPS_SIZE, L1_CACHE_BYTES); int cpu, numa_node_id = -2; bool active = false; mutex_lock(&xps_map_mutex); dev_maps = xmap_dereference(dev->xps_maps); /* allocate memory for queue storage */ for_each_online_cpu(cpu) { if (!cpumask_test_cpu(cpu, mask)) continue; if (!new_dev_maps) new_dev_maps = kzalloc(maps_sz, GFP_KERNEL); if (!new_dev_maps) { mutex_unlock(&xps_map_mutex); return -ENOMEM; } map = dev_maps ? xmap_dereference(dev_maps->cpu_map[cpu]) : NULL; map = expand_xps_map(map, cpu, index); if (!map) goto error; RCU_INIT_POINTER(new_dev_maps->cpu_map[cpu], map); } if (!new_dev_maps) goto out_no_new_maps; for_each_possible_cpu(cpu) { if (cpumask_test_cpu(cpu, mask) && cpu_online(cpu)) { /* add queue to CPU maps */ int pos = 0; map = xmap_dereference(new_dev_maps->cpu_map[cpu]); while ((pos < map->len) && (map->queues[pos] != index)) pos++; if (pos == map->len) map->queues[map->len++] = index; #ifdef CONFIG_NUMA if (numa_node_id == -2) numa_node_id = cpu_to_node(cpu); else if (numa_node_id != cpu_to_node(cpu)) numa_node_id = -1; #endif } else if (dev_maps) { /* fill in the new device map from the old device map */ map = xmap_dereference(dev_maps->cpu_map[cpu]); RCU_INIT_POINTER(new_dev_maps->cpu_map[cpu], map); } } rcu_assign_pointer(dev->xps_maps, new_dev_maps); /* Cleanup old maps */ if (dev_maps) { for_each_possible_cpu(cpu) { new_map = xmap_dereference(new_dev_maps->cpu_map[cpu]); map = xmap_dereference(dev_maps->cpu_map[cpu]); if (map && map != new_map) kfree_rcu(map, rcu); } kfree_rcu(dev_maps, rcu); } dev_maps = new_dev_maps; active = true; out_no_new_maps: /* update Tx queue numa node */ netdev_queue_numa_node_write(netdev_get_tx_queue(dev, index), (numa_node_id >= 0) ? numa_node_id : NUMA_NO_NODE); if (!dev_maps) goto out_no_maps; /* removes queue from unused CPUs */ for_each_possible_cpu(cpu) { if (cpumask_test_cpu(cpu, mask) && cpu_online(cpu)) continue; if (remove_xps_queue(dev_maps, cpu, index)) active = true; } /* free map if not active */ if (!active) { RCU_INIT_POINTER(dev->xps_maps, NULL); kfree_rcu(dev_maps, rcu); } out_no_maps: mutex_unlock(&xps_map_mutex); return 0; error: /* remove any maps that we added */ for_each_possible_cpu(cpu) { new_map = xmap_dereference(new_dev_maps->cpu_map[cpu]); map = dev_maps ? xmap_dereference(dev_maps->cpu_map[cpu]) : NULL; if (new_map && new_map != map) kfree(new_map); } mutex_unlock(&xps_map_mutex); kfree(new_dev_maps); return -ENOMEM; } EXPORT_SYMBOL(netif_set_xps_queue); #endif /* * Routine to help set real_num_tx_queues. To avoid skbs mapped to queues * greater then real_num_tx_queues stale skbs on the qdisc must be flushed. */ int netif_set_real_num_tx_queues(struct net_device *dev, unsigned int txq) { bool disabling; int rc; disabling = txq < dev->real_num_tx_queues; if (txq < 1 || txq > dev->num_tx_queues) return -EINVAL; if (dev->reg_state == NETREG_REGISTERED || dev->reg_state == NETREG_UNREGISTERING) { ASSERT_RTNL(); rc = netdev_queue_update_kobjects(dev, dev->real_num_tx_queues, txq); if (rc) return rc; if (dev->num_tc) netif_setup_tc(dev, txq); dev->real_num_tx_queues = txq; if (disabling) { synchronize_net(); qdisc_reset_all_tx_gt(dev, txq); #ifdef CONFIG_XPS netif_reset_xps_queues_gt(dev, txq); #endif } } else { dev->real_num_tx_queues = txq; } return 0; } EXPORT_SYMBOL(netif_set_real_num_tx_queues); #ifdef CONFIG_SYSFS /** * netif_set_real_num_rx_queues - set actual number of RX queues used * @dev: Network device * @rxq: Actual number of RX queues * * This must be called either with the rtnl_lock held or before * registration of the net device. Returns 0 on success, or a * negative error code. If called before registration, it always * succeeds. */ int netif_set_real_num_rx_queues(struct net_device *dev, unsigned int rxq) { int rc; if (rxq < 1 || rxq > dev->num_rx_queues) return -EINVAL; if (dev->reg_state == NETREG_REGISTERED) { ASSERT_RTNL(); rc = net_rx_queue_update_kobjects(dev, dev->real_num_rx_queues, rxq); if (rc) return rc; } dev->real_num_rx_queues = rxq; return 0; } EXPORT_SYMBOL(netif_set_real_num_rx_queues); #endif /** * netif_get_num_default_rss_queues - default number of RSS queues * * This routine should set an upper limit on the number of RSS queues * used by default by multiqueue devices. */ int netif_get_num_default_rss_queues(void) { return is_kdump_kernel() ? 1 : min_t(int, DEFAULT_MAX_NUM_RSS_QUEUES, num_online_cpus()); } EXPORT_SYMBOL(netif_get_num_default_rss_queues); static void __netif_reschedule(struct Qdisc *q) { struct softnet_data *sd; unsigned long flags; local_irq_save(flags); sd = this_cpu_ptr(&softnet_data); q->next_sched = NULL; *sd->output_queue_tailp = q; sd->output_queue_tailp = &q->next_sched; raise_softirq_irqoff(NET_TX_SOFTIRQ); local_irq_restore(flags); } void __netif_schedule(struct Qdisc *q) { if (!test_and_set_bit(__QDISC_STATE_SCHED, &q->state)) __netif_reschedule(q); } EXPORT_SYMBOL(__netif_schedule); struct dev_kfree_skb_cb { enum skb_free_reason reason; }; static struct dev_kfree_skb_cb *get_kfree_skb_cb(const struct sk_buff *skb) { return (struct dev_kfree_skb_cb *)skb->cb; } void netif_schedule_queue(struct netdev_queue *txq) { rcu_read_lock(); if (!(txq->state & QUEUE_STATE_ANY_XOFF)) { struct Qdisc *q = rcu_dereference(txq->qdisc); __netif_schedule(q); } rcu_read_unlock(); } EXPORT_SYMBOL(netif_schedule_queue); /** * netif_wake_subqueue - allow sending packets on subqueue * @dev: network device * @queue_index: sub queue index * * Resume individual transmit queue of a device with multiple transmit queues. */ void netif_wake_subqueue(struct net_device *dev, u16 queue_index) { struct netdev_queue *txq = netdev_get_tx_queue(dev, queue_index); if (test_and_clear_bit(__QUEUE_STATE_DRV_XOFF, &txq->state)) { struct Qdisc *q; rcu_read_lock(); q = rcu_dereference(txq->qdisc); __netif_schedule(q); rcu_read_unlock(); } } EXPORT_SYMBOL(netif_wake_subqueue); void netif_tx_wake_queue(struct netdev_queue *dev_queue) { if (test_and_clear_bit(__QUEUE_STATE_DRV_XOFF, &dev_queue->state)) { struct Qdisc *q; rcu_read_lock(); q = rcu_dereference(dev_queue->qdisc); __netif_schedule(q); rcu_read_unlock(); } } EXPORT_SYMBOL(netif_tx_wake_queue); void __dev_kfree_skb_irq(struct sk_buff *skb, enum skb_free_reason reason) { unsigned long flags; if (unlikely(!skb)) return; if (likely(atomic_read(&skb->users) == 1)) { smp_rmb(); atomic_set(&skb->users, 0); } else if (likely(!atomic_dec_and_test(&skb->users))) { return; } get_kfree_skb_cb(skb)->reason = reason; local_irq_save(flags); skb->next = __this_cpu_read(softnet_data.completion_queue); __this_cpu_write(softnet_data.completion_queue, skb); raise_softirq_irqoff(NET_TX_SOFTIRQ); local_irq_restore(flags); } EXPORT_SYMBOL(__dev_kfree_skb_irq); void __dev_kfree_skb_any(struct sk_buff *skb, enum skb_free_reason reason) { if (in_irq() || irqs_disabled()) __dev_kfree_skb_irq(skb, reason); else dev_kfree_skb(skb); } EXPORT_SYMBOL(__dev_kfree_skb_any); /** * netif_device_detach - mark device as removed * @dev: network device * * Mark device as removed from system and therefore no longer available. */ void netif_device_detach(struct net_device *dev) { if (test_and_clear_bit(__LINK_STATE_PRESENT, &dev->state) && netif_running(dev)) { netif_tx_stop_all_queues(dev); } } EXPORT_SYMBOL(netif_device_detach); /** * netif_device_attach - mark device as attached * @dev: network device * * Mark device as attached from system and restart if needed. */ void netif_device_attach(struct net_device *dev) { if (!test_and_set_bit(__LINK_STATE_PRESENT, &dev->state) && netif_running(dev)) { netif_tx_wake_all_queues(dev); __netdev_watchdog_up(dev); } } EXPORT_SYMBOL(netif_device_attach); /* * Returns a Tx hash based on the given packet descriptor a Tx queues' number * to be used as a distribution range. */ u16 __skb_tx_hash(const struct net_device *dev, struct sk_buff *skb, unsigned int num_tx_queues) { u32 hash; u16 qoffset = 0; u16 qcount = num_tx_queues; if (skb_rx_queue_recorded(skb)) { hash = skb_get_rx_queue(skb); while (unlikely(hash >= num_tx_queues)) hash -= num_tx_queues; return hash; } if (dev->num_tc) { u8 tc = netdev_get_prio_tc_map(dev, skb->priority); qoffset = dev->tc_to_txq[tc].offset; qcount = dev->tc_to_txq[tc].count; } return (u16) reciprocal_scale(skb_get_hash(skb), qcount) + qoffset; } EXPORT_SYMBOL(__skb_tx_hash); static void skb_warn_bad_offload(const struct sk_buff *skb) { static const netdev_features_t null_features; struct net_device *dev = skb->dev; const char *name = ""; if (!net_ratelimit()) return; if (dev) { if (dev->dev.parent) name = dev_driver_string(dev->dev.parent); else name = netdev_name(dev); } WARN(1, "%s: caps=(%pNF, %pNF) len=%d data_len=%d gso_size=%d " "gso_type=%d ip_summed=%d\n", name, dev ? &dev->features : &null_features, skb->sk ? &skb->sk->sk_route_caps : &null_features, skb->len, skb->data_len, skb_shinfo(skb)->gso_size, skb_shinfo(skb)->gso_type, skb->ip_summed); } /* * Invalidate hardware checksum when packet is to be mangled, and * complete checksum manually on outgoing path. */ int skb_checksum_help(struct sk_buff *skb) { __wsum csum; int ret = 0, offset; if (skb->ip_summed == CHECKSUM_COMPLETE) goto out_set_summed; if (unlikely(skb_shinfo(skb)->gso_size)) { skb_warn_bad_offload(skb); return -EINVAL; } /* Before computing a checksum, we should make sure no frag could * be modified by an external entity : checksum could be wrong. */ if (skb_has_shared_frag(skb)) { ret = __skb_linearize(skb); if (ret) goto out; } offset = skb_checksum_start_offset(skb); BUG_ON(offset >= skb_headlen(skb)); csum = skb_checksum(skb, offset, skb->len - offset, 0); offset += skb->csum_offset; BUG_ON(offset + sizeof(__sum16) > skb_headlen(skb)); if (skb_cloned(skb) && !skb_clone_writable(skb, offset + sizeof(__sum16))) { ret = pskb_expand_head(skb, 0, 0, GFP_ATOMIC); if (ret) goto out; } *(__sum16 *)(skb->data + offset) = csum_fold(csum) ?: CSUM_MANGLED_0; out_set_summed: skb->ip_summed = CHECKSUM_NONE; out: return ret; } EXPORT_SYMBOL(skb_checksum_help); /* skb_csum_offload_check - Driver helper function to determine if a device * with limited checksum offload capabilities is able to offload the checksum * for a given packet. * * Arguments: * skb - sk_buff for the packet in question * spec - contains the description of what device can offload * csum_encapped - returns true if the checksum being offloaded is * encpasulated. That is it is checksum for the transport header * in the inner headers. * checksum_help - when set indicates that helper function should * call skb_checksum_help if offload checks fail * * Returns: * true: Packet has passed the checksum checks and should be offloadable to * the device (a driver may still need to check for additional * restrictions of its device) * false: Checksum is not offloadable. If checksum_help was set then * skb_checksum_help was called to resolve checksum for non-GSO * packets and when IP protocol is not SCTP */ bool __skb_csum_offload_chk(struct sk_buff *skb, const struct skb_csum_offl_spec *spec, bool *csum_encapped, bool csum_help) { struct iphdr *iph; struct ipv6hdr *ipv6; void *nhdr; int protocol; u8 ip_proto; if (skb->protocol == htons(ETH_P_8021Q) || skb->protocol == htons(ETH_P_8021AD)) { if (!spec->vlan_okay) goto need_help; } /* We check whether the checksum refers to a transport layer checksum in * the outermost header or an encapsulated transport layer checksum that * corresponds to the inner headers of the skb. If the checksum is for * something else in the packet we need help. */ if (skb_checksum_start_offset(skb) == skb_transport_offset(skb)) { /* Non-encapsulated checksum */ protocol = eproto_to_ipproto(vlan_get_protocol(skb)); nhdr = skb_network_header(skb); *csum_encapped = false; if (spec->no_not_encapped) goto need_help; } else if (skb->encapsulation && spec->encap_okay && skb_checksum_start_offset(skb) == skb_inner_transport_offset(skb)) { /* Encapsulated checksum */ *csum_encapped = true; switch (skb->inner_protocol_type) { case ENCAP_TYPE_ETHER: protocol = eproto_to_ipproto(skb->inner_protocol); break; case ENCAP_TYPE_IPPROTO: protocol = skb->inner_protocol; break; } nhdr = skb_inner_network_header(skb); } else { goto need_help; } switch (protocol) { case IPPROTO_IP: if (!spec->ipv4_okay) goto need_help; iph = nhdr; ip_proto = iph->protocol; if (iph->ihl != 5 && !spec->ip_options_okay) goto need_help; break; case IPPROTO_IPV6: if (!spec->ipv6_okay) goto need_help; if (spec->no_encapped_ipv6 && *csum_encapped) goto need_help; ipv6 = nhdr; nhdr += sizeof(*ipv6); ip_proto = ipv6->nexthdr; break; default: goto need_help; } ip_proto_again: switch (ip_proto) { case IPPROTO_TCP: if (!spec->tcp_okay || skb->csum_offset != offsetof(struct tcphdr, check)) goto need_help; break; case IPPROTO_UDP: if (!spec->udp_okay || skb->csum_offset != offsetof(struct udphdr, check)) goto need_help; break; case IPPROTO_SCTP: if (!spec->sctp_okay || skb->csum_offset != offsetof(struct sctphdr, checksum)) goto cant_help; break; case NEXTHDR_HOP: case NEXTHDR_ROUTING: case NEXTHDR_DEST: { u8 *opthdr = nhdr; if (protocol != IPPROTO_IPV6 || !spec->ext_hdrs_okay) goto need_help; ip_proto = opthdr[0]; nhdr += (opthdr[1] + 1) << 3; goto ip_proto_again; } default: goto need_help; } /* Passed the tests for offloading checksum */ return true; need_help: if (csum_help && !skb_shinfo(skb)->gso_size) skb_checksum_help(skb); cant_help: return false; } EXPORT_SYMBOL(__skb_csum_offload_chk); __be16 skb_network_protocol(struct sk_buff *skb, int *depth) { __be16 type = skb->protocol; /* Tunnel gso handlers can set protocol to ethernet. */ if (type == htons(ETH_P_TEB)) { struct ethhdr *eth; if (unlikely(!pskb_may_pull(skb, sizeof(struct ethhdr)))) return 0; eth = (struct ethhdr *)skb->data; type = eth->h_proto; } return __vlan_get_protocol(skb, type, depth); } /** * skb_mac_gso_segment - mac layer segmentation handler. * @skb: buffer to segment * @features: features for the output path (see dev->features) */ struct sk_buff *skb_mac_gso_segment(struct sk_buff *skb, netdev_features_t features) { struct sk_buff *segs = ERR_PTR(-EPROTONOSUPPORT); struct packet_offload *ptype; int vlan_depth = skb->mac_len; __be16 type = skb_network_protocol(skb, &vlan_depth); if (unlikely(!type)) return ERR_PTR(-EINVAL); __skb_pull(skb, vlan_depth); rcu_read_lock(); list_for_each_entry_rcu(ptype, &offload_base, list) { if (ptype->type == type && ptype->callbacks.gso_segment) { segs = ptype->callbacks.gso_segment(skb, features); break; } } rcu_read_unlock(); __skb_push(skb, skb->data - skb_mac_header(skb)); return segs; } EXPORT_SYMBOL(skb_mac_gso_segment); /* openvswitch calls this on rx path, so we need a different check. */ static inline bool skb_needs_check(struct sk_buff *skb, bool tx_path) { if (tx_path) return skb->ip_summed != CHECKSUM_PARTIAL; return skb->ip_summed == CHECKSUM_NONE; } /** * __skb_gso_segment - Perform segmentation on skb. * @skb: buffer to segment * @features: features for the output path (see dev->features) * @tx_path: whether it is called in TX path * * This function segments the given skb and returns a list of segments. * * It may return NULL if the skb requires no segmentation. This is * only possible when GSO is used for verifying header integrity. * * Segmentation preserves SKB_SGO_CB_OFFSET bytes of previous skb cb. */ struct sk_buff *__skb_gso_segment(struct sk_buff *skb, netdev_features_t features, bool tx_path) { struct sk_buff *segs; if (unlikely(skb_needs_check(skb, tx_path))) { int err; /* We're going to init ->check field in TCP or UDP header */ err = skb_cow_head(skb, 0); if (err < 0) return ERR_PTR(err); } /* Only report GSO partial support if it will enable us to * support segmentation on this frame without needing additional * work. */ if (features & NETIF_F_GSO_PARTIAL) { netdev_features_t partial_features = NETIF_F_GSO_ROBUST; struct net_device *dev = skb->dev; partial_features |= dev->features & dev->gso_partial_features; if (!skb_gso_ok(skb, features | partial_features)) features &= ~NETIF_F_GSO_PARTIAL; } BUILD_BUG_ON(SKB_SGO_CB_OFFSET + sizeof(*SKB_GSO_CB(skb)) > sizeof(skb->cb)); SKB_GSO_CB(skb)->mac_offset = skb_headroom(skb); SKB_GSO_CB(skb)->encap_level = 0; skb_reset_mac_header(skb); skb_reset_mac_len(skb); segs = skb_mac_gso_segment(skb, features); if (unlikely(skb_needs_check(skb, tx_path) && !IS_ERR(segs))) skb_warn_bad_offload(skb); return segs; } EXPORT_SYMBOL(__skb_gso_segment); /* Take action when hardware reception checksum errors are detected. */ #ifdef CONFIG_BUG void netdev_rx_csum_fault(struct net_device *dev) { if (net_ratelimit()) { pr_err("%s: hw csum failure\n", dev ? dev->name : ""); dump_stack(); } } EXPORT_SYMBOL(netdev_rx_csum_fault); #endif /* Actually, we should eliminate this check as soon as we know, that: * 1. IOMMU is present and allows to map all the memory. * 2. No high memory really exists on this machine. */ static int illegal_highdma(struct net_device *dev, struct sk_buff *skb) { #ifdef CONFIG_HIGHMEM int i; if (!(dev->features & NETIF_F_HIGHDMA)) { for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) { skb_frag_t *frag = &skb_shinfo(skb)->frags[i]; if (PageHighMem(skb_frag_page(frag))) return 1; } } if (PCI_DMA_BUS_IS_PHYS) { struct device *pdev = dev->dev.parent; if (!pdev) return 0; for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) { skb_frag_t *frag = &skb_shinfo(skb)->frags[i]; dma_addr_t addr = page_to_phys(skb_frag_page(frag)); if (!pdev->dma_mask || addr + PAGE_SIZE - 1 > *pdev->dma_mask) return 1; } } #endif return 0; } /* If MPLS offload request, verify we are testing hardware MPLS features * instead of standard features for the netdev. */ #if IS_ENABLED(CONFIG_NET_MPLS_GSO) static netdev_features_t net_mpls_features(struct sk_buff *skb, netdev_features_t features, __be16 type) { if (eth_p_mpls(type)) features &= skb->dev->mpls_features; return features; } #else static netdev_features_t net_mpls_features(struct sk_buff *skb, netdev_features_t features, __be16 type) { return features; } #endif static netdev_features_t harmonize_features(struct sk_buff *skb, netdev_features_t features) { int tmp; __be16 type; type = skb_network_protocol(skb, &tmp); features = net_mpls_features(skb, features, type); if (skb->ip_summed != CHECKSUM_NONE && !can_checksum_protocol(features, type)) { features &= ~(NETIF_F_CSUM_MASK | NETIF_F_GSO_MASK); } if (illegal_highdma(skb->dev, skb)) features &= ~NETIF_F_SG; return features; } netdev_features_t passthru_features_check(struct sk_buff *skb, struct net_device *dev, netdev_features_t features) { return features; } EXPORT_SYMBOL(passthru_features_check); static netdev_features_t dflt_features_check(struct sk_buff *skb, struct net_device *dev, netdev_features_t features) { return vlan_features_check(skb, features); } static netdev_features_t gso_features_check(const struct sk_buff *skb, struct net_device *dev, netdev_features_t features) { u16 gso_segs = skb_shinfo(skb)->gso_segs; if (gso_segs > dev->gso_max_segs) return features & ~NETIF_F_GSO_MASK; /* Support for GSO partial features requires software * intervention before we can actually process the packets * so we need to strip support for any partial features now * and we can pull them back in after we have partially * segmented the frame. */ if (!(skb_shinfo(skb)->gso_type & SKB_GSO_PARTIAL)) features &= ~dev->gso_partial_features; /* Make sure to clear the IPv4 ID mangling feature if the * IPv4 header has the potential to be fragmented. */ if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV4) { struct iphdr *iph = skb->encapsulation ? inner_ip_hdr(skb) : ip_hdr(skb); if (!(iph->frag_off & htons(IP_DF))) features &= ~NETIF_F_TSO_MANGLEID; } return features; } netdev_features_t netif_skb_features(struct sk_buff *skb) { struct net_device *dev = skb->dev; netdev_features_t features = dev->features; if (skb_is_gso(skb)) features = gso_features_check(skb, dev, features); /* If encapsulation offload request, verify we are testing * hardware encapsulation features instead of standard * features for the netdev */ if (skb->encapsulation) features &= dev->hw_enc_features; if (skb_vlan_tagged(skb)) features = netdev_intersect_features(features, dev->vlan_features | NETIF_F_HW_VLAN_CTAG_TX | NETIF_F_HW_VLAN_STAG_TX); if (dev->netdev_ops->ndo_features_check) features &= dev->netdev_ops->ndo_features_check(skb, dev, features); else features &= dflt_features_check(skb, dev, features); return harmonize_features(skb, features); } EXPORT_SYMBOL(netif_skb_features); static int xmit_one(struct sk_buff *skb, struct net_device *dev, struct netdev_queue *txq, bool more) { unsigned int len; int rc; if (!list_empty(&ptype_all) || !list_empty(&dev->ptype_all)) dev_queue_xmit_nit(skb, dev); len = skb->len; trace_net_dev_start_xmit(skb, dev); rc = netdev_start_xmit(skb, dev, txq, more); trace_net_dev_xmit(skb, rc, dev, len); return rc; } static int xmit_list(struct sk_buff *list, struct net_device *dev, struct netdev_queue *txq) { unsigned int len; int rc; struct sk_buff *skb = list, *head = list; /* Call the taps for individual skb's in the list. */ if (!list_empty(&ptype_all)) { while (skb) { struct sk_buff *next = skb->next; skb->next = NULL; dev_queue_xmit_nit(skb, dev); skb = next; /* Keep the original list intact. */ head->next = skb; head = head->next; } } len = list->len; trace_net_dev_start_xmit(list, dev); rc = netdev_start_xmit(list, dev, txq, false); trace_net_dev_xmit(list, rc, dev, len); return rc; } struct sk_buff *dev_hard_start_xmit(struct sk_buff *first, struct net_device *dev, struct netdev_queue *txq, int *ret) { struct sk_buff *skb = first; int rc = NETDEV_TX_OK; while (skb) { struct sk_buff *next = skb->next; skb->next = NULL; rc = xmit_one(skb, dev, txq, next != NULL); if (unlikely(!dev_xmit_complete(rc))) { skb->next = next; goto out; } skb = next; if (netif_tx_queue_stopped(txq) && skb) { rc = NETDEV_TX_BUSY; break; } } out: *ret = rc; return skb; } struct sk_buff *dev_hard_start_xmit_list(struct sk_buff *first, struct net_device *dev, struct netdev_queue *txq, int *ret) { struct sk_buff *skb = first; int rc = NETDEV_TX_OK; if (skb) { rc = xmit_list(skb, dev, txq); if (unlikely(!dev_xmit_complete(rc))) goto out; skb = NULL; } out: *ret = rc; return skb; } static struct sk_buff *validate_xmit_vlan(struct sk_buff *skb, netdev_features_t features) { if (skb_vlan_tag_present(skb) && !vlan_hw_offload_capable(features, skb->vlan_proto)) skb = __vlan_hwaccel_push_inside(skb); return skb; } static struct sk_buff *validate_xmit_skb(struct sk_buff *skb, struct net_device *dev) { netdev_features_t features; features = netif_skb_features(skb); skb = validate_xmit_vlan(skb, features); if (unlikely(!skb)) goto out_null; if (netif_needs_gso(skb, features)) { struct sk_buff *segs; __be16 src_port = tcp_hdr(skb)->source; __be16 dest_port = tcp_hdr(skb)->dest; trace_print_skb_gso(skb, src_port, dest_port); segs = skb_gso_segment(skb, features); if (IS_ERR(segs)) { goto out_kfree_skb; } else if (segs) { consume_skb(skb); skb = segs; } } else { if (skb_needs_linearize(skb, features) && __skb_linearize(skb)) goto out_kfree_skb; /* If packet is not checksummed and device does not * support checksumming for this protocol, complete * checksumming here. */ if (skb->ip_summed == CHECKSUM_PARTIAL) { if (skb->encapsulation) skb_set_inner_transport_header(skb, skb_checksum_start_offset(skb)); else skb_set_transport_header(skb, skb_checksum_start_offset(skb)); if (!(features & NETIF_F_CSUM_MASK) && skb_checksum_help(skb)) goto out_kfree_skb; } } return skb; out_kfree_skb: kfree_skb(skb); out_null: atomic_long_inc(&dev->tx_dropped); return NULL; } struct sk_buff *validate_xmit_skb_list(struct sk_buff *skb, struct net_device *dev) { struct sk_buff *next, *head = NULL, *tail; for (; skb != NULL; skb = next) { next = skb->next; skb->next = NULL; /* in case skb wont be segmented, point to itself */ skb->prev = skb; skb = validate_xmit_skb(skb, dev); if (!skb) continue; if (!head) head = skb; else tail->next = skb; /* If skb was segmented, skb->prev points to * the last segment. If not, it still contains skb. */ tail = skb->prev; } return head; } EXPORT_SYMBOL_GPL(validate_xmit_skb_list); static void qdisc_pkt_len_init(struct sk_buff *skb) { const struct skb_shared_info *shinfo = skb_shinfo(skb); qdisc_skb_cb(skb)->pkt_len = skb->len; /* To get more precise estimation of bytes sent on wire, * we add to pkt_len the headers size of all segments */ if (shinfo->gso_size) { unsigned int hdr_len; u16 gso_segs = shinfo->gso_segs; /* mac layer + network layer */ hdr_len = skb_transport_header(skb) - skb_mac_header(skb); /* + transport layer */ if (likely(shinfo->gso_type & (SKB_GSO_TCPV4 | SKB_GSO_TCPV6))) { const struct tcphdr *th; struct tcphdr _tcphdr; th = skb_header_pointer(skb, skb_transport_offset(skb), sizeof(_tcphdr), &_tcphdr); if (likely(th)) hdr_len += __tcp_hdrlen(th); } else { struct udphdr _udphdr; if (skb_header_pointer(skb, skb_transport_offset(skb), sizeof(_udphdr), &_udphdr)) hdr_len += sizeof(struct udphdr); } if (shinfo->gso_type & SKB_GSO_DODGY) gso_segs = DIV_ROUND_UP(skb->len - hdr_len, shinfo->gso_size); qdisc_skb_cb(skb)->pkt_len += (gso_segs - 1) * hdr_len; } } static inline int __dev_xmit_skb(struct sk_buff *skb, struct Qdisc *q, struct net_device *dev, struct netdev_queue *txq) { spinlock_t *root_lock = qdisc_lock(q); struct sk_buff *to_free = NULL; bool contended; int rc; qdisc_calculate_pkt_len(skb, q); /* * Heuristic to force contended enqueues to serialize on a * separate lock before trying to get qdisc main lock. * This permits qdisc->running owner to get the lock more * often and dequeue packets faster. */ contended = qdisc_is_running(q); if (unlikely(contended)) spin_lock(&q->busylock); spin_lock(root_lock); if (unlikely(test_bit(__QDISC_STATE_DEACTIVATED, &q->state))) { __qdisc_drop(skb, &to_free); rc = NET_XMIT_DROP; } else if ((q->flags & TCQ_F_CAN_BYPASS) && !qdisc_qlen(q) && qdisc_run_begin(q)) { /* * This is a work-conserving queue; there are no old skbs * waiting to be sent out; and the qdisc is not running - * xmit the skb directly. */ qdisc_bstats_update(q, skb); if (sch_direct_xmit(skb, q, dev, txq, root_lock, true)) { if (unlikely(contended)) { spin_unlock(&q->busylock); contended = false; } __qdisc_run(q); } else qdisc_run_end(q); rc = NET_XMIT_SUCCESS; } else { rc = q->enqueue(skb, q, &to_free) & NET_XMIT_MASK; if (qdisc_run_begin(q)) { if (unlikely(contended)) { spin_unlock(&q->busylock); contended = false; } __qdisc_run(q); } } spin_unlock(root_lock); if (unlikely(to_free)) kfree_skb_list(to_free); if (unlikely(contended)) spin_unlock(&q->busylock); return rc; } #if IS_ENABLED(CONFIG_CGROUP_NET_PRIO) static void skb_update_prio(struct sk_buff *skb) { const struct netprio_map *map; const struct sock *sk; unsigned int prioidx; if (skb->priority) return; map = rcu_dereference_bh(skb->dev->priomap); if (!map) return; sk = skb_to_full_sk(skb); if (!sk) return; prioidx = sock_cgroup_prioidx(&sk->sk_cgrp_data); if (prioidx < map->priomap_len) skb->priority = map->priomap[prioidx]; } #else #define skb_update_prio(skb) #endif /** * dev_loopback_xmit - loop back @skb * @net: network namespace this loopback is happening in * @sk: sk needed to be a netfilter okfn * @skb: buffer to transmit */ int dev_loopback_xmit(struct net *net, struct sock *sk, struct sk_buff *skb) { skb_reset_mac_header(skb); __skb_pull(skb, skb_network_offset(skb)); skb->pkt_type = PACKET_LOOPBACK; skb->ip_summed = CHECKSUM_UNNECESSARY; WARN_ON(!skb_dst(skb)); skb_dst_force(skb); netif_rx_ni(skb); return 0; } EXPORT_SYMBOL(dev_loopback_xmit); #ifdef CONFIG_NET_EGRESS static struct sk_buff * sch_handle_egress(struct sk_buff *skb, int *ret, struct net_device *dev) { struct tcf_proto *cl = rcu_dereference_bh(dev->egress_cl_list); struct tcf_result cl_res; if (!cl) return skb; /* skb->tc_verd and qdisc_skb_cb(skb)->pkt_len were already set * earlier by the caller. */ qdisc_bstats_cpu_update(cl->q, skb); switch (tc_classify(skb, cl, &cl_res, false)) { case TC_ACT_OK: case TC_ACT_RECLASSIFY: skb->tc_index = TC_H_MIN(cl_res.classid); break; case TC_ACT_SHOT: qdisc_qstats_cpu_drop(cl->q); *ret = NET_XMIT_DROP; kfree_skb(skb); return NULL; case TC_ACT_STOLEN: case TC_ACT_QUEUED: *ret = NET_XMIT_SUCCESS; consume_skb(skb); return NULL; case TC_ACT_REDIRECT: /* No need to push/pop skb's mac_header here on egress! */ skb_do_redirect(skb); *ret = NET_XMIT_SUCCESS; return NULL; default: break; } return skb; } #endif /* CONFIG_NET_EGRESS */ static inline int get_xps_queue(struct net_device *dev, struct sk_buff *skb) { #ifdef CONFIG_XPS struct xps_dev_maps *dev_maps; struct xps_map *map; int queue_index = -1; rcu_read_lock(); dev_maps = rcu_dereference(dev->xps_maps); if (dev_maps) { map = rcu_dereference( dev_maps->cpu_map[skb->sender_cpu - 1]); if (map) { if (map->len == 1) queue_index = map->queues[0]; else queue_index = map->queues[reciprocal_scale(skb_get_hash(skb), map->len)]; if (unlikely(queue_index >= dev->real_num_tx_queues)) queue_index = -1; } } rcu_read_unlock(); return queue_index; #else return -1; #endif } static u16 __netdev_pick_tx(struct net_device *dev, struct sk_buff *skb) { struct sock *sk = skb->sk; int queue_index = sk_tx_queue_get(sk); if (queue_index < 0 || skb->ooo_okay || queue_index >= dev->real_num_tx_queues) { int new_index = get_xps_queue(dev, skb); if (new_index < 0) new_index = skb_tx_hash(dev, skb); if (queue_index != new_index && sk && sk_fullsock(sk) && rcu_access_pointer(sk->sk_dst_cache)) sk_tx_queue_set(sk, new_index); queue_index = new_index; } return queue_index; } struct netdev_queue *netdev_pick_tx(struct net_device *dev, struct sk_buff *skb, void *accel_priv) { int queue_index = 0; #ifdef CONFIG_XPS u32 sender_cpu = skb->sender_cpu - 1; if (sender_cpu >= (u32)NR_CPUS) skb->sender_cpu = raw_smp_processor_id() + 1; #endif if (dev->real_num_tx_queues != 1) { const struct net_device_ops *ops = dev->netdev_ops; if (ops->ndo_select_queue) queue_index = ops->ndo_select_queue(dev, skb, accel_priv, __netdev_pick_tx); else queue_index = __netdev_pick_tx(dev, skb); if (!accel_priv) queue_index = netdev_cap_txqueue(dev, queue_index); } skb_set_queue_mapping(skb, queue_index); return netdev_get_tx_queue(dev, queue_index); } /** * __dev_queue_xmit - transmit a buffer * @skb: buffer to transmit * @accel_priv: private data used for L2 forwarding offload * @skb_list: Boolean used for skb list processing. * * Queue a buffer for transmission to a network device. The caller must * have set the device and priority and built the buffer before calling * this function. The function can be called from an interrupt. * * A negative errno code is returned on a failure. A success does not * guarantee the frame will be transmitted as it may be dropped due * to congestion or traffic shaping. * * ----------------------------------------------------------------------------------- * I notice this method can also return errors from the queue disciplines, * including NET_XMIT_DROP, which is a positive value. So, errors can also * be positive. * * Regardless of the return value, the skb is consumed, so it is currently * difficult to retry a send to this method. (You can bump the ref count * before sending to hold a reference for retry if you are careful.) * * When calling this method, interrupts MUST be enabled. This is because * the BH enable code must have IRQs enabled so that it will not deadlock. * --BLG */ static int __dev_queue_xmit(struct sk_buff *skb, void *accel_priv, bool skb_list) { struct net_device *dev = skb->dev; struct netdev_queue *txq; struct Qdisc *q; int rc = -ENOMEM; skb_reset_mac_header(skb); skb_assert_len(skb); if (unlikely(skb_shinfo(skb)->tx_flags & SKBTX_SCHED_TSTAMP)) __skb_tstamp_tx(skb, NULL, skb->sk, SCM_TSTAMP_SCHED); /* Disable soft irqs for various locks below. Also * stops preemption for RCU. */ rcu_read_lock_bh(); skb_update_prio(skb); qdisc_pkt_len_init(skb); #ifdef CONFIG_NET_CLS_ACT skb->tc_verd = SET_TC_AT(skb->tc_verd, AT_EGRESS); # ifdef CONFIG_NET_EGRESS if (static_key_false(&egress_needed)) { skb = sch_handle_egress(skb, &rc, dev); if (!skb) goto out; } # endif #endif /* If device/qdisc don't need skb->dst, release it right now while * its hot in this cpu cache. */ if (dev->priv_flags & IFF_XMIT_DST_RELEASE) skb_dst_drop(skb); else skb_dst_force(skb); txq = netdev_pick_tx(dev, skb, accel_priv); q = rcu_dereference_bh(txq->qdisc); trace_net_dev_queue(skb); if (q->enqueue) { rc = __dev_xmit_skb(skb, q, dev, txq); goto out; } /* The device has no queue. Common case for software devices: * loopback, all the sorts of tunnels... * Really, it is unlikely that netif_tx_lock protection is necessary * here. (f.e. loopback and IP tunnels are clean ignoring statistics * counters.) * However, it is possible, that they rely on protection * made by us here. * Check this and shot the lock. It is not prone from deadlocks. *Either shot noqueue qdisc, it is even simpler 8) */ if (dev->flags & IFF_UP) { int cpu = smp_processor_id(); /* ok because BHs are off */ if (txq->xmit_lock_owner != cpu) { if (dev_xmit_recursion()) goto recursion_alert; skb = validate_xmit_skb(skb, dev); if (!skb) goto out; HARD_TX_LOCK(dev, txq, cpu); if (!netif_xmit_stopped(txq)) { dev_xmit_recursion_inc(); if (likely(!skb_list)) skb = dev_hard_start_xmit(skb, dev, txq, &rc); else skb = dev_hard_start_xmit_list(skb, dev, txq, &rc); dev_xmit_recursion_dec(); if (dev_xmit_complete(rc)) { HARD_TX_UNLOCK(dev, txq); goto out; } } HARD_TX_UNLOCK(dev, txq); net_crit_ratelimited("Virtual device %s asks to queue packet!\n", dev->name); } else { /* Recursion is detected! It is possible, * unfortunately */ recursion_alert: net_crit_ratelimited("Dead loop on virtual device %s, fix it urgently!\n", dev->name); } } rc = -ENETDOWN; rcu_read_unlock_bh(); atomic_long_inc(&dev->tx_dropped); kfree_skb_list(skb); return rc; out: rcu_read_unlock_bh(); return rc; } int dev_queue_xmit(struct sk_buff *skb) { return __dev_queue_xmit(skb, NULL, false); } EXPORT_SYMBOL(dev_queue_xmit); int dev_queue_xmit_accel(struct sk_buff *skb, void *accel_priv) { return __dev_queue_xmit(skb, accel_priv, false); } EXPORT_SYMBOL(dev_queue_xmit_accel); int dev_queue_xmit_list(struct sk_buff *skb) { return __dev_queue_xmit(skb, NULL, true); } EXPORT_SYMBOL(dev_queue_xmit_list); int dev_direct_xmit(struct sk_buff *skb, u16 queue_id) { struct net_device *dev = skb->dev; struct sk_buff *orig_skb = skb; struct netdev_queue *txq; int ret = NETDEV_TX_BUSY; if (unlikely(!netif_running(dev) || !netif_carrier_ok(dev))) goto drop; skb = validate_xmit_skb_list(skb, dev); if (skb != orig_skb) goto drop; skb_set_queue_mapping(skb, queue_id); txq = skb_get_tx_queue(dev, skb); local_bh_disable(); HARD_TX_LOCK(dev, txq, smp_processor_id()); if (!netif_xmit_frozen_or_drv_stopped(txq)) ret = netdev_start_xmit(skb, dev, txq, false); HARD_TX_UNLOCK(dev, txq); local_bh_enable(); if (!dev_xmit_complete(ret)) kfree_skb(skb); return ret; drop: atomic_long_inc(&dev->tx_dropped); kfree_skb_list(skb); return NET_XMIT_DROP; } /************************************************************************* * Receiver routines *************************************************************************/ int netdev_max_backlog __read_mostly = 1000; EXPORT_SYMBOL(netdev_max_backlog); int netdev_tstamp_prequeue __read_mostly = 1; int netdev_budget __read_mostly = 300; int weight_p __read_mostly = 64; /* old backlog weight */ /* Called with irq disabled */ static inline void ____napi_schedule(struct softnet_data *sd, struct napi_struct *napi) { list_add_tail(&napi->poll_list, &sd->poll_list); __raise_softirq_irqoff(NET_RX_SOFTIRQ); } #ifdef CONFIG_RPS /* One global table that all flow-based protocols share. */ struct rps_sock_flow_table __rcu *rps_sock_flow_table __read_mostly; EXPORT_SYMBOL(rps_sock_flow_table); u32 rps_cpu_mask __read_mostly; EXPORT_SYMBOL(rps_cpu_mask); struct static_key rps_needed __read_mostly; EXPORT_SYMBOL(rps_needed); static struct rps_dev_flow * set_rps_cpu(struct net_device *dev, struct sk_buff *skb, struct rps_dev_flow *rflow, u16 next_cpu) { if (next_cpu < nr_cpu_ids) { #ifdef CONFIG_RFS_ACCEL struct netdev_rx_queue *rxqueue; struct rps_dev_flow_table *flow_table; struct rps_dev_flow *old_rflow; u32 flow_id; u16 rxq_index; int rc; /* Should we steer this flow to a different hardware queue? */ if (!skb_rx_queue_recorded(skb) || !dev->rx_cpu_rmap || !(dev->features & NETIF_F_NTUPLE)) goto out; rxq_index = cpu_rmap_lookup_index(dev->rx_cpu_rmap, next_cpu); if (rxq_index == skb_get_rx_queue(skb)) goto out; rxqueue = dev->_rx + rxq_index; flow_table = rcu_dereference(rxqueue->rps_flow_table); if (!flow_table) goto out; flow_id = skb_get_hash(skb) & flow_table->mask; rc = dev->netdev_ops->ndo_rx_flow_steer(dev, skb, rxq_index, flow_id); if (rc < 0) goto out; old_rflow = rflow; rflow = &flow_table->flows[flow_id]; rflow->filter = rc; if (old_rflow->filter == rflow->filter) old_rflow->filter = RPS_NO_FILTER; out: #endif rflow->last_qtail = per_cpu(softnet_data, next_cpu).input_queue_head; } rflow->cpu = next_cpu; return rflow; } /* * get_rps_cpu is called from netif_receive_skb and returns the target * CPU from the RPS map of the receiving queue for a given skb. * rcu_read_lock must be held on entry. */ static int get_rps_cpu(struct net_device *dev, struct sk_buff *skb, struct rps_dev_flow **rflowp) { const struct rps_sock_flow_table *sock_flow_table; struct netdev_rx_queue *rxqueue = dev->_rx; struct rps_dev_flow_table *flow_table; struct rps_map *map; int cpu = -1; u32 tcpu; u32 hash; if (skb_rx_queue_recorded(skb)) { u16 index = skb_get_rx_queue(skb); if (unlikely(index >= dev->real_num_rx_queues)) { WARN_ONCE(dev->real_num_rx_queues > 1, "%s received packet on queue %u, but number " "of RX queues is %u\n", dev->name, index, dev->real_num_rx_queues); goto done; } rxqueue += index; } /* Avoid computing hash if RFS/RPS is not active for this rxqueue */ flow_table = rcu_dereference(rxqueue->rps_flow_table); map = rcu_dereference(rxqueue->rps_map); if (!flow_table && !map) goto done; skb_reset_network_header(skb); hash = skb_get_hash(skb); if (!hash) goto done; sock_flow_table = rcu_dereference(rps_sock_flow_table); if (flow_table && sock_flow_table) { struct rps_dev_flow *rflow; u32 next_cpu; u32 ident; /* First check into global flow table if there is a match */ ident = sock_flow_table->ents[hash & sock_flow_table->mask]; if ((ident ^ hash) & ~rps_cpu_mask) goto try_rps; next_cpu = ident & rps_cpu_mask; /* OK, now we know there is a match, * we can look at the local (per receive queue) flow table */ rflow = &flow_table->flows[hash & flow_table->mask]; tcpu = rflow->cpu; /* * If the desired CPU (where last recvmsg was done) is * different from current CPU (one in the rx-queue flow * table entry), switch if one of the following holds: * - Current CPU is unset (>= nr_cpu_ids). * - Current CPU is offline. * - The current CPU's queue tail has advanced beyond the * last packet that was enqueued using this table entry. * This guarantees that all previous packets for the flow * have been dequeued, thus preserving in order delivery. */ if (unlikely(tcpu != next_cpu) && (tcpu >= nr_cpu_ids || !cpu_online(tcpu) || ((int)(per_cpu(softnet_data, tcpu).input_queue_head - rflow->last_qtail)) >= 0)) { tcpu = next_cpu; rflow = set_rps_cpu(dev, skb, rflow, next_cpu); } if (tcpu < nr_cpu_ids && cpu_online(tcpu)) { *rflowp = rflow; cpu = tcpu; goto done; } } try_rps: if (map) { tcpu = map->cpus[reciprocal_scale(hash, map->len)]; if (cpu_online(tcpu)) { cpu = tcpu; goto done; } } done: return cpu; } #ifdef CONFIG_RFS_ACCEL /** * rps_may_expire_flow - check whether an RFS hardware filter may be removed * @dev: Device on which the filter was set * @rxq_index: RX queue index * @flow_id: Flow ID passed to ndo_rx_flow_steer() * @filter_id: Filter ID returned by ndo_rx_flow_steer() * * Drivers that implement ndo_rx_flow_steer() should periodically call * this function for each installed filter and remove the filters for * which it returns %true. */ bool rps_may_expire_flow(struct net_device *dev, u16 rxq_index, u32 flow_id, u16 filter_id) { struct netdev_rx_queue *rxqueue = dev->_rx + rxq_index; struct rps_dev_flow_table *flow_table; struct rps_dev_flow *rflow; bool expire = true; unsigned int cpu; rcu_read_lock(); flow_table = rcu_dereference(rxqueue->rps_flow_table); if (flow_table && flow_id <= flow_table->mask) { rflow = &flow_table->flows[flow_id]; cpu = ACCESS_ONCE(rflow->cpu); if (rflow->filter == filter_id && cpu < nr_cpu_ids && ((int)(per_cpu(softnet_data, cpu).input_queue_head - rflow->last_qtail) < (int)(10 * flow_table->mask))) expire = false; } rcu_read_unlock(); return expire; } EXPORT_SYMBOL(rps_may_expire_flow); #endif /* CONFIG_RFS_ACCEL */ /* Called from hardirq (IPI) context */ static void rps_trigger_softirq(void *data) { struct softnet_data *sd = data; ____napi_schedule(sd, &sd->backlog); sd->received_rps++; } #endif /* CONFIG_RPS */ /* * Check if this softnet_data structure is another cpu one * If yes, queue it to our IPI list and return 1 * If no, return 0 */ static int rps_ipi_queued(struct softnet_data *sd) { #ifdef CONFIG_RPS struct softnet_data *mysd = this_cpu_ptr(&softnet_data); if (sd != mysd) { sd->rps_ipi_next = mysd->rps_ipi_list; mysd->rps_ipi_list = sd; __raise_softirq_irqoff(NET_RX_SOFTIRQ); return 1; } #endif /* CONFIG_RPS */ return 0; } #ifdef CONFIG_NET_FLOW_LIMIT int netdev_flow_limit_table_len __read_mostly = (1 << 12); #endif static bool skb_flow_limit(struct sk_buff *skb, unsigned int qlen) { #ifdef CONFIG_NET_FLOW_LIMIT struct sd_flow_limit *fl; struct softnet_data *sd; unsigned int old_flow, new_flow; if (qlen < (netdev_max_backlog >> 1)) return false; sd = this_cpu_ptr(&softnet_data); rcu_read_lock(); fl = rcu_dereference(sd->flow_limit); if (fl) { new_flow = skb_get_hash(skb) & (fl->num_buckets - 1); old_flow = fl->history[fl->history_head]; fl->history[fl->history_head] = new_flow; fl->history_head++; fl->history_head &= FLOW_LIMIT_HISTORY - 1; if (likely(fl->buckets[old_flow])) fl->buckets[old_flow]--; if (++fl->buckets[new_flow] > (FLOW_LIMIT_HISTORY >> 1)) { fl->count++; rcu_read_unlock(); return true; } } rcu_read_unlock(); #endif return false; } /* * enqueue_to_backlog is called to queue an skb to a per CPU backlog * queue (may be a remote CPU queue). */ static int enqueue_to_backlog(struct sk_buff *skb, int cpu, unsigned int *qtail) { struct softnet_data *sd; unsigned long flags; unsigned int qlen; sd = &per_cpu(softnet_data, cpu); local_irq_save(flags); rps_lock(sd); if (!netif_running(skb->dev)) goto drop; qlen = skb_queue_len(&sd->input_pkt_queue); if (qlen <= netdev_max_backlog && !skb_flow_limit(skb, qlen)) { if (qlen) { enqueue: __skb_queue_tail(&sd->input_pkt_queue, skb); input_queue_tail_incr_save(sd, qtail); rps_unlock(sd); local_irq_restore(flags); return NET_RX_SUCCESS; } /* Schedule NAPI for backlog device * We can use non atomic operation since we own the queue lock */ if (!__test_and_set_bit(NAPI_STATE_SCHED, &sd->backlog.state)) { if (!rps_ipi_queued(sd)) ____napi_schedule(sd, &sd->backlog); } goto enqueue; } drop: sd->dropped++; rps_unlock(sd); local_irq_restore(flags); atomic_long_inc(&skb->dev->rx_dropped); kfree_skb(skb); return NET_RX_DROP; } static struct netdev_rx_queue *netif_get_rxqueue(struct sk_buff *skb) { struct net_device *dev = skb->dev; struct netdev_rx_queue *rxqueue; rxqueue = dev->_rx; if (skb_rx_queue_recorded(skb)) { u16 index = skb_get_rx_queue(skb); if (unlikely(index >= dev->real_num_rx_queues)) { WARN_ONCE(dev->real_num_rx_queues > 1, "%s received packet on queue %u, but number " "of RX queues is %u\n", dev->name, index, dev->real_num_rx_queues); return rxqueue; /* Return first rxqueue */ } rxqueue += index; } return rxqueue; } static u32 netif_receive_generic_xdp(struct sk_buff *skb, struct xdp_buff *xdp, struct bpf_prog *xdp_prog) { struct netdev_rx_queue *rxqueue; void *orig_data, *orig_data_end; u32 metalen, act = XDP_DROP; int hlen, off; u32 mac_len; /* Reinjected packets coming from act_mirred or similar should * not get XDP generic processing. */ if (skb_cloned(skb)) return XDP_PASS; /* XDP packets must be linear and must have sufficient headroom * of XDP_PACKET_HEADROOM bytes. This is the guarantee that also * native XDP provides, thus we need to do it here as well. */ if (skb_is_nonlinear(skb) || skb_headroom(skb) < XDP_PACKET_HEADROOM) { int hroom = XDP_PACKET_HEADROOM - skb_headroom(skb); int troom = skb->tail + skb->data_len - skb->end; /* In case we have to go down the path and also linearize, * then lets do the pskb_expand_head() work just once here. */ if (pskb_expand_head(skb, hroom > 0 ? ALIGN(hroom, NET_SKB_PAD) : 0, troom > 0 ? troom + 128 : 0, GFP_ATOMIC)) goto do_drop; if (troom > 0 && __skb_linearize(skb)) goto do_drop; } /* The XDP program wants to see the packet starting at the MAC * header. */ mac_len = skb->data - skb_mac_header(skb); hlen = skb_headlen(skb) + mac_len; xdp->data = skb->data - mac_len; xdp->data_meta = xdp->data; xdp->data_end = xdp->data + hlen; xdp->data_hard_start = skb->data - skb_headroom(skb); orig_data_end = xdp->data_end; orig_data = xdp->data; rxqueue = netif_get_rxqueue(skb); xdp->rxq = &rxqueue->xdp_rxq; act = bpf_prog_run_xdp(xdp_prog, xdp); off = xdp->data - orig_data; if (off > 0) __skb_pull(skb, off); else if (off < 0) __skb_push(skb, -off); /* check if bpf_xdp_adjust_tail was used. it can only "shrink" * pckt. */ off = orig_data_end - xdp->data_end; if (off != 0) { skb_set_tail_pointer(skb, xdp->data_end - xdp->data); skb->len -= off; } switch (act) { case XDP_REDIRECT: case XDP_TX: __skb_push(skb, mac_len); break; case XDP_PASS: metalen = xdp->data - xdp->data_meta; if (metalen) skb_metadata_set(skb, metalen); break; default: bpf_warn_invalid_xdp_action(act); /* fall through */ case XDP_ABORTED: trace_xdp_exception(skb->dev, xdp_prog, act); /* fall through */ case XDP_DROP: do_drop: kfree_skb(skb); break; } return act; } /* When doing generic XDP we have to bypass the qdisc layer and the * network taps in order to match in-driver-XDP behavior. */ void generic_xdp_tx(struct sk_buff *skb, struct bpf_prog *xdp_prog) { struct net_device *dev = skb->dev; struct netdev_queue *txq; bool free_skb = true; int cpu, rc; txq = netdev_pick_tx(dev, skb, NULL); cpu = smp_processor_id(); HARD_TX_LOCK(dev, txq, cpu); if (!netif_xmit_stopped(txq)) { rc = netdev_start_xmit(skb, dev, txq, 0); if (dev_xmit_complete(rc)) free_skb = false; } HARD_TX_UNLOCK(dev, txq); if (free_skb) { trace_xdp_exception(dev, xdp_prog, XDP_TX); kfree_skb(skb); } } EXPORT_SYMBOL_GPL(generic_xdp_tx); static DEFINE_STATIC_KEY_FALSE(generic_xdp_needed_key); int do_xdp_generic(struct bpf_prog *xdp_prog, struct sk_buff *skb) { if (xdp_prog) { struct xdp_buff xdp; u32 act; int err; act = netif_receive_generic_xdp(skb, &xdp, xdp_prog); if (act != XDP_PASS) { switch (act) { case XDP_REDIRECT: err = xdp_do_generic_redirect(skb->dev, skb, &xdp, xdp_prog); if (err) goto out_redir; break; case XDP_TX: generic_xdp_tx(skb, xdp_prog); break; } return XDP_DROP; } } return XDP_PASS; out_redir: kfree_skb(skb); return XDP_DROP; } EXPORT_SYMBOL_GPL(do_xdp_generic); static int netif_rx_internal(struct sk_buff *skb) { int ret; net_timestamp_check(netdev_tstamp_prequeue, skb); trace_netif_rx(skb); if (static_branch_unlikely(&generic_xdp_needed_key)) { int ret; preempt_disable(); rcu_read_lock(); ret = do_xdp_generic(rcu_dereference(skb->dev->xdp_prog), skb); rcu_read_unlock(); preempt_enable(); /* Consider XDP consuming the packet a success from * the netdev point of view we do not want to count * this as an error. */ if (ret != XDP_PASS) return NET_RX_SUCCESS; } #ifdef CONFIG_RPS if (static_key_false(&rps_needed)) { struct rps_dev_flow voidflow, *rflow = &voidflow; int cpu; preempt_disable(); rcu_read_lock(); cpu = get_rps_cpu(skb->dev, skb, &rflow); if (cpu < 0) cpu = smp_processor_id(); ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail); rcu_read_unlock(); preempt_enable(); } else #endif { unsigned int qtail; ret = enqueue_to_backlog(skb, get_cpu(), &qtail); put_cpu(); } return ret; } /** * netif_rx - post buffer to the network code * @skb: buffer to post * * This function receives a packet from a device driver and queues it for * the upper (protocol) levels to process. It always succeeds. The buffer * may be dropped during processing for congestion control or by the * protocol layers. * * return values: * NET_RX_SUCCESS (no congestion) * NET_RX_DROP (packet was dropped) * */ int netif_rx(struct sk_buff *skb) { trace_netif_rx_entry(skb); return netif_rx_internal(skb); } EXPORT_SYMBOL(netif_rx); int netif_rx_ni(struct sk_buff *skb) { int err; trace_netif_rx_ni_entry(skb); preempt_disable(); err = netif_rx_internal(skb); if (local_softirq_pending()) do_softirq(); preempt_enable(); return err; } EXPORT_SYMBOL(netif_rx_ni); static __latent_entropy void net_tx_action(struct softirq_action *h) { struct softnet_data *sd = this_cpu_ptr(&softnet_data); if (sd->completion_queue) { struct sk_buff *clist; local_irq_disable(); clist = sd->completion_queue; sd->completion_queue = NULL; local_irq_enable(); while (clist) { struct sk_buff *skb = clist; clist = clist->next; WARN_ON(atomic_read(&skb->users)); if (likely(get_kfree_skb_cb(skb)->reason == SKB_REASON_CONSUMED)) trace_consume_skb(skb); else trace_kfree_skb(skb, net_tx_action); if (skb->fclone != SKB_FCLONE_UNAVAILABLE) __kfree_skb(skb); else __kfree_skb_defer(skb); } __kfree_skb_flush(); } if (sd->output_queue) { struct Qdisc *head; local_irq_disable(); head = sd->output_queue; sd->output_queue = NULL; sd->output_queue_tailp = &sd->output_queue; local_irq_enable(); while (head) { struct Qdisc *q = head; spinlock_t *root_lock; head = head->next_sched; root_lock = qdisc_lock(q); spin_lock(root_lock); /* We need to make sure head->next_sched is read * before clearing __QDISC_STATE_SCHED */ smp_mb__before_atomic(); clear_bit(__QDISC_STATE_SCHED, &q->state); qdisc_run(q); spin_unlock(root_lock); } } } #if IS_ENABLED(CONFIG_BRIDGE) && IS_ENABLED(CONFIG_ATM_LANE) /* This hook is defined here for ATM LANE */ int (*br_fdb_test_addr_hook)(struct net_device *dev, unsigned char *addr) __read_mostly; EXPORT_SYMBOL_GPL(br_fdb_test_addr_hook); #endif static inline struct sk_buff * sch_handle_ingress(struct sk_buff *skb, struct packet_type **pt_prev, int *ret, struct net_device *orig_dev) { #ifdef CONFIG_NET_CLS_ACT struct tcf_proto *cl = rcu_dereference_bh(skb->dev->ingress_cl_list); struct tcf_result cl_res; /* If there's at least one ingress present somewhere (so * we get here via enabled static key), remaining devices * that are not configured with an ingress qdisc will bail * out here. */ if (!cl) return skb; if (*pt_prev) { *ret = deliver_skb(skb, *pt_prev, orig_dev); *pt_prev = NULL; } qdisc_skb_cb(skb)->pkt_len = skb->len; skb->tc_verd = SET_TC_AT(skb->tc_verd, AT_INGRESS); qdisc_bstats_cpu_update(cl->q, skb); switch (tc_classify(skb, cl, &cl_res, false)) { case TC_ACT_OK: case TC_ACT_RECLASSIFY: skb->tc_index = TC_H_MIN(cl_res.classid); break; case TC_ACT_SHOT: qdisc_qstats_cpu_drop(cl->q); kfree_skb(skb); return NULL; case TC_ACT_STOLEN: case TC_ACT_QUEUED: consume_skb(skb); return NULL; case TC_ACT_REDIRECT: /* skb_mac_header check was done by cls/act_bpf, so * we can safely push the L2 header back before * redirecting to another netdev */ __skb_push(skb, skb->mac_len); skb_do_redirect(skb); return NULL; default: break; } #endif /* CONFIG_NET_CLS_ACT */ return skb; } /** * netdev_is_rx_handler_busy - check if receive handler is registered * @dev: device to check * * Check if a receive handler is already registered for a given device. * Return true if there one. * * The caller must hold the rtnl_mutex. */ bool netdev_is_rx_handler_busy(struct net_device *dev) { ASSERT_RTNL(); return dev && rtnl_dereference(dev->rx_handler); } EXPORT_SYMBOL_GPL(netdev_is_rx_handler_busy); /** * netdev_rx_handler_register - register receive handler * @dev: device to register a handler for * @rx_handler: receive handler to register * @rx_handler_data: data pointer that is used by rx handler * * Register a receive handler for a device. This handler will then be * called from __netif_receive_skb. A negative errno code is returned * on a failure. * * The caller must hold the rtnl_mutex. * * For a general description of rx_handler, see enum rx_handler_result. */ int netdev_rx_handler_register(struct net_device *dev, rx_handler_func_t *rx_handler, void *rx_handler_data) { ASSERT_RTNL(); if (dev->rx_handler) return -EBUSY; /* Note: rx_handler_data must be set before rx_handler */ rcu_assign_pointer(dev->rx_handler_data, rx_handler_data); rcu_assign_pointer(dev->rx_handler, rx_handler); return 0; } EXPORT_SYMBOL_GPL(netdev_rx_handler_register); /** * netdev_rx_handler_unregister - unregister receive handler * @dev: device to unregister a handler from * * Unregister a receive handler from a device. * * The caller must hold the rtnl_mutex. */ void netdev_rx_handler_unregister(struct net_device *dev) { ASSERT_RTNL(); RCU_INIT_POINTER(dev->rx_handler, NULL); /* a reader seeing a non NULL rx_handler in a rcu_read_lock() * section has a guarantee to see a non NULL rx_handler_data * as well. */ synchronize_net(); RCU_INIT_POINTER(dev->rx_handler_data, NULL); } EXPORT_SYMBOL_GPL(netdev_rx_handler_unregister); /* * Limit the use of PFMEMALLOC reserves to those protocols that implement * the special handling of PFMEMALLOC skbs. */ static bool skb_pfmemalloc_protocol(struct sk_buff *skb) { switch (skb->protocol) { case htons(ETH_P_ARP): case htons(ETH_P_IP): case htons(ETH_P_IPV6): case htons(ETH_P_8021Q): case htons(ETH_P_8021AD): return true; default: return false; } } static inline int nf_ingress(struct sk_buff *skb, struct packet_type **pt_prev, int *ret, struct net_device *orig_dev) { #ifdef CONFIG_NETFILTER_INGRESS if (nf_hook_ingress_active(skb)) { int ingress_retval; if (*pt_prev) { *ret = deliver_skb(skb, *pt_prev, orig_dev); *pt_prev = NULL; } rcu_read_lock(); ingress_retval = nf_hook_ingress(skb); rcu_read_unlock(); return ingress_retval; } #endif /* CONFIG_NETFILTER_INGRESS */ return 0; } int (*gsb_nw_stack_recv)(struct sk_buff *skb) __rcu __read_mostly; EXPORT_SYMBOL(gsb_nw_stack_recv); int (*athrs_fast_nat_recv)(struct sk_buff *skb, struct packet_type *pt_temp) __rcu __read_mostly; EXPORT_SYMBOL(athrs_fast_nat_recv); int (*embms_tm_multicast_recv)(struct sk_buff *skb) __rcu __read_mostly; EXPORT_SYMBOL(embms_tm_multicast_recv); static int __netif_receive_skb_core(struct sk_buff *skb, bool pfmemalloc) { struct packet_type *ptype, *pt_prev; rx_handler_func_t *rx_handler; struct net_device *orig_dev; bool deliver_exact = false; int ret = NET_RX_DROP; __be16 type; int (*gsb_ns_recv)(struct sk_buff *skb); int (*fast_recv)(struct sk_buff *skb, struct packet_type *pt_temp); int (*embms_recv)(struct sk_buff *skb); net_timestamp_check(!netdev_tstamp_prequeue, skb); trace_netif_receive_skb(skb); orig_dev = skb->dev; skb_reset_network_header(skb); if (!skb_transport_header_was_set(skb)) skb_reset_transport_header(skb); skb_reset_mac_len(skb); pt_prev = NULL; another_round: skb->skb_iif = skb->dev->ifindex; __this_cpu_inc(softnet_data.processed); if (skb->protocol == cpu_to_be16(ETH_P_8021Q) || skb->protocol == cpu_to_be16(ETH_P_8021AD)) { skb = skb_vlan_untag(skb); if (unlikely(!skb)) goto out; } #ifdef CONFIG_NET_CLS_ACT if (skb->tc_verd & TC_NCLS) { skb->tc_verd = CLR_TC_NCLS(skb->tc_verd); goto ncls; } #endif if (pfmemalloc) goto skip_taps; list_for_each_entry_rcu(ptype, &ptype_all, list) { if (pt_prev) ret = deliver_skb(skb, pt_prev, orig_dev); pt_prev = ptype; } list_for_each_entry_rcu(ptype, &skb->dev->ptype_all, list) { if (pt_prev) ret = deliver_skb(skb, pt_prev, orig_dev); pt_prev = ptype; } skip_taps: #ifdef CONFIG_NET_INGRESS if (static_key_false(&ingress_needed)) { skb = sch_handle_ingress(skb, &pt_prev, &ret, orig_dev); if (!skb) goto out; if (nf_ingress(skb, &pt_prev, &ret, orig_dev) < 0) goto out; } #endif gsb_ns_recv = rcu_dereference(gsb_nw_stack_recv); if (gsb_ns_recv) { if (gsb_ns_recv(skb)) { ret = NET_RX_SUCCESS; goto out; } } fast_recv = rcu_dereference(athrs_fast_nat_recv); if (fast_recv) { if (fast_recv(skb, pt_prev)) { ret = NET_RX_SUCCESS; goto out; } } embms_recv = rcu_dereference(embms_tm_multicast_recv); if (embms_recv) embms_recv(skb); #ifdef CONFIG_NET_CLS_ACT skb->tc_verd = 0; ncls: #endif if (pfmemalloc && !skb_pfmemalloc_protocol(skb)) goto drop; if (skb_vlan_tag_present(skb)) { if (pt_prev) { ret = deliver_skb(skb, pt_prev, orig_dev); pt_prev = NULL; } if (vlan_do_receive(&skb)) goto another_round; else if (unlikely(!skb)) goto out; } rx_handler = rcu_dereference(skb->dev->rx_handler); if (rx_handler) { if (pt_prev) { ret = deliver_skb(skb, pt_prev, orig_dev); pt_prev = NULL; } switch (rx_handler(&skb)) { case RX_HANDLER_CONSUMED: ret = NET_RX_SUCCESS; goto out; case RX_HANDLER_ANOTHER: goto another_round; case RX_HANDLER_EXACT: deliver_exact = true; case RX_HANDLER_PASS: break; default: BUG(); } } if (unlikely(skb_vlan_tag_present(skb))) { if (skb_vlan_tag_get_id(skb)) skb->pkt_type = PACKET_OTHERHOST; /* Note: we might in the future use prio bits * and set skb->priority like in vlan_do_receive() * For the time being, just ignore Priority Code Point */ skb->vlan_tci = 0; } type = skb->protocol; /* deliver only exact match when indicated */ if (likely(!deliver_exact)) { deliver_ptype_list_skb(skb, &pt_prev, orig_dev, type, &ptype_base[ntohs(type) & PTYPE_HASH_MASK]); } deliver_ptype_list_skb(skb, &pt_prev, orig_dev, type, &orig_dev->ptype_specific); if (unlikely(skb->dev != orig_dev)) { deliver_ptype_list_skb(skb, &pt_prev, orig_dev, type, &skb->dev->ptype_specific); } if (pt_prev) { if (unlikely(skb_orphan_frags_rx(skb, GFP_ATOMIC))) goto drop; else ret = pt_prev->func(skb, skb->dev, pt_prev, orig_dev); } else { drop: if (!deliver_exact) atomic_long_inc(&skb->dev->rx_dropped); else atomic_long_inc(&skb->dev->rx_nohandler); kfree_skb(skb); /* Jamal, now you will not able to escape explaining * me how you were going to use this. :-) */ ret = NET_RX_DROP; } out: return ret; } /** * netif_receive_skb_core - special purpose version of netif_receive_skb * @skb: buffer to process * * More direct receive version of netif_receive_skb(). It should * only be used by callers that have a need to skip RPS and Generic XDP. * Caller must also take care of handling if (page_is_)pfmemalloc. * * This function may only be called from softirq context and interrupts * should be enabled. * * Return values (usually ignored): * NET_RX_SUCCESS: no congestion * NET_RX_DROP: packet was dropped */ int netif_receive_skb_core(struct sk_buff *skb) { int ret; rcu_read_lock(); ret = __netif_receive_skb_core(skb, false); rcu_read_unlock(); return ret; } EXPORT_SYMBOL(netif_receive_skb_core); static int __netif_receive_skb(struct sk_buff *skb) { int ret; if (sk_memalloc_socks() && skb_pfmemalloc(skb)) { unsigned long pflags = current->flags; /* * PFMEMALLOC skbs are special, they should * - be delivered to SOCK_MEMALLOC sockets only * - stay away from userspace * - have bounded memory usage * * Use PF_MEMALLOC as this saves us from propagating the allocation * context down to all allocation sites. */ current->flags |= PF_MEMALLOC; ret = __netif_receive_skb_core(skb, true); tsk_restore_flags(current, pflags, PF_MEMALLOC); } else ret = __netif_receive_skb_core(skb, false); return ret; } static int generic_xdp_install(struct net_device *dev, struct netdev_bpf *xdp) { struct bpf_prog *old = rtnl_dereference(dev->xdp_prog); struct bpf_prog *new = xdp->prog; int ret = 0; switch (xdp->command) { case XDP_SETUP_PROG: rcu_assign_pointer(dev->xdp_prog, new); if (old) bpf_prog_put(old); if (old && !new) { static_branch_dec(&generic_xdp_needed_key); } else if (new && !old) { static_branch_inc(&generic_xdp_needed_key); dev_disable_lro(dev); } break; case XDP_QUERY_PROG: xdp->prog_id = old ? old->aux->id : 0; break; default: ret = -EINVAL; break; } return ret; } static int netif_receive_skb_internal(struct sk_buff *skb) { int ret; net_timestamp_check(netdev_tstamp_prequeue, skb); if (skb_defer_rx_timestamp(skb)) return NET_RX_SUCCESS; if (static_branch_unlikely(&generic_xdp_needed_key)) { int ret; preempt_disable(); rcu_read_lock(); ret = do_xdp_generic(rcu_dereference(skb->dev->xdp_prog), skb); rcu_read_unlock(); preempt_enable(); if (ret != XDP_PASS) return NET_RX_DROP; } rcu_read_lock(); #ifdef CONFIG_RPS if (static_key_false(&rps_needed)) { struct rps_dev_flow voidflow, *rflow = &voidflow; int cpu = get_rps_cpu(skb->dev, skb, &rflow); if (cpu >= 0) { ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail); rcu_read_unlock(); return ret; } } #endif ret = __netif_receive_skb(skb); rcu_read_unlock(); return ret; } /** * netif_receive_skb - process receive buffer from network * @skb: buffer to process * * netif_receive_skb() is the main receive data processing function. * It always succeeds. The buffer may be dropped during processing * for congestion control or by the protocol layers. * * This function may only be called from softirq context and interrupts * should be enabled. * * Return values (usually ignored): * NET_RX_SUCCESS: no congestion * NET_RX_DROP: packet was dropped */ int netif_receive_skb(struct sk_buff *skb) { trace_netif_receive_skb_entry(skb); return netif_receive_skb_internal(skb); } EXPORT_SYMBOL(netif_receive_skb); DEFINE_PER_CPU(struct work_struct, flush_works); /* Network device is going away, flush any packets still pending */ static void flush_backlog(struct work_struct *work) { struct sk_buff *skb, *tmp; struct softnet_data *sd; local_bh_disable(); sd = this_cpu_ptr(&softnet_data); local_irq_disable(); rps_lock(sd); skb_queue_walk_safe(&sd->input_pkt_queue, skb, tmp) { if (skb->dev->reg_state == NETREG_UNREGISTERING) { __skb_unlink(skb, &sd->input_pkt_queue); dev_kfree_skb_irq(skb); input_queue_head_incr(sd); } } rps_unlock(sd); local_irq_enable(); skb_queue_walk_safe(&sd->process_queue, skb, tmp) { if (skb->dev->reg_state == NETREG_UNREGISTERING) { __skb_unlink(skb, &sd->process_queue); kfree_skb(skb); input_queue_head_incr(sd); } } local_bh_enable(); } static void flush_all_backlogs(void) { unsigned int cpu; get_online_cpus(); for_each_online_cpu(cpu) queue_work_on(cpu, system_highpri_wq, per_cpu_ptr(&flush_works, cpu)); for_each_online_cpu(cpu) flush_work(per_cpu_ptr(&flush_works, cpu)); put_online_cpus(); } static int napi_gro_complete(struct sk_buff *skb) { struct packet_offload *ptype; __be16 type = skb->protocol; struct list_head *head = &offload_base; int err = -ENOENT; BUILD_BUG_ON(sizeof(struct napi_gro_cb) > sizeof(skb->cb)); if (NAPI_GRO_CB(skb)->count == 1) { skb_shinfo(skb)->gso_size = 0; goto out; } rcu_read_lock(); list_for_each_entry_rcu(ptype, head, list) { if (ptype->type != type || !ptype->callbacks.gro_complete) continue; err = ptype->callbacks.gro_complete(skb, 0); break; } rcu_read_unlock(); if (err) { WARN_ON(&ptype->list == head); kfree_skb(skb); return NET_RX_SUCCESS; } out: __this_cpu_add(softnet_data.gro_coalesced, NAPI_GRO_CB(skb)->count > 1); return netif_receive_skb_internal(skb); } /* napi->gro_list contains packets ordered by age. * youngest packets at the head of it. * Complete skbs in reverse order to reduce latencies. */ void napi_gro_flush(struct napi_struct *napi, bool flush_old) { struct sk_buff *skb, *prev = NULL; /* scan list and build reverse chain */ for (skb = napi->gro_list; skb != NULL; skb = skb->next) { skb->prev = prev; prev = skb; } for (skb = prev; skb; skb = prev) { skb->next = NULL; if (flush_old && NAPI_GRO_CB(skb)->age == jiffies) return; prev = skb->prev; napi_gro_complete(skb); napi->gro_count--; } napi->gro_list = NULL; } EXPORT_SYMBOL(napi_gro_flush); static void gro_list_prepare(struct napi_struct *napi, struct sk_buff *skb) { struct sk_buff *p; unsigned int maclen = skb->dev->hard_header_len; u32 hash = skb_get_hash_raw(skb); for (p = napi->gro_list; p; p = p->next) { unsigned long diffs; NAPI_GRO_CB(p)->flush = 0; NAPI_GRO_CB(p)->flush_id = 0; if (hash != skb_get_hash_raw(p)) { NAPI_GRO_CB(p)->same_flow = 0; continue; } diffs = (unsigned long)p->dev ^ (unsigned long)skb->dev; diffs |= p->vlan_tci ^ skb->vlan_tci; diffs |= skb_metadata_dst_cmp(p, skb); diffs |= skb_metadata_differs(p, skb); if (maclen == ETH_HLEN) diffs |= compare_ether_header(skb_mac_header(p), skb_mac_header(skb)); else if (!diffs) diffs = memcmp(skb_mac_header(p), skb_mac_header(skb), maclen); NAPI_GRO_CB(p)->same_flow = !diffs; } } static void skb_gro_reset_offset(struct sk_buff *skb) { const struct skb_shared_info *pinfo = skb_shinfo(skb); const skb_frag_t *frag0 = &pinfo->frags[0]; NAPI_GRO_CB(skb)->data_offset = 0; NAPI_GRO_CB(skb)->frag0 = NULL; NAPI_GRO_CB(skb)->frag0_len = 0; if (skb_mac_header(skb) == skb_tail_pointer(skb) && pinfo->nr_frags && !PageHighMem(skb_frag_page(frag0)) && (!NET_IP_ALIGN || !(skb_frag_off(frag0) & 3))) { NAPI_GRO_CB(skb)->frag0 = skb_frag_address(frag0); NAPI_GRO_CB(skb)->frag0_len = min_t(unsigned int, skb_frag_size(frag0), skb->end - skb->tail); } } static void gro_pull_from_frag0(struct sk_buff *skb, int grow) { struct skb_shared_info *pinfo = skb_shinfo(skb); BUG_ON(skb->end - skb->tail < grow); memcpy(skb_tail_pointer(skb), NAPI_GRO_CB(skb)->frag0, grow); skb->data_len -= grow; skb->tail += grow; pinfo->frags[0].page_offset += grow; skb_frag_size_sub(&pinfo->frags[0], grow); if (unlikely(!skb_frag_size(&pinfo->frags[0]))) { skb_frag_unref(skb, 0); memmove(pinfo->frags, pinfo->frags + 1, --pinfo->nr_frags * sizeof(pinfo->frags[0])); } } static enum gro_result dev_gro_receive(struct napi_struct *napi, struct sk_buff *skb) { struct sk_buff **pp = NULL; struct packet_offload *ptype; __be16 type = skb->protocol; struct list_head *head = &offload_base; int same_flow; enum gro_result ret; int grow; if (netif_elide_gro(skb->dev)) goto normal; if (skb_is_gso(skb) || skb_has_frag_list(skb) || skb->csum_bad) goto normal; gro_list_prepare(napi, skb); rcu_read_lock(); list_for_each_entry_rcu(ptype, head, list) { if (ptype->type != type || !ptype->callbacks.gro_receive) continue; skb_set_network_header(skb, skb_gro_offset(skb)); skb_reset_mac_len(skb); NAPI_GRO_CB(skb)->same_flow = 0; NAPI_GRO_CB(skb)->flush = 0; NAPI_GRO_CB(skb)->free = 0; NAPI_GRO_CB(skb)->encap_mark = 0; NAPI_GRO_CB(skb)->recursion_counter = 0; NAPI_GRO_CB(skb)->is_fou = 0; NAPI_GRO_CB(skb)->gro_remcsum_start = 0; /* Setup for GRO checksum validation */ switch (skb->ip_summed) { case CHECKSUM_COMPLETE: NAPI_GRO_CB(skb)->csum = skb->csum; NAPI_GRO_CB(skb)->csum_valid = 1; NAPI_GRO_CB(skb)->csum_cnt = 0; break; case CHECKSUM_UNNECESSARY: NAPI_GRO_CB(skb)->csum_cnt = skb->csum_level + 1; NAPI_GRO_CB(skb)->csum_valid = 0; break; default: NAPI_GRO_CB(skb)->csum_cnt = 0; NAPI_GRO_CB(skb)->csum_valid = 0; } pp = ptype->callbacks.gro_receive(&napi->gro_list, skb); break; } rcu_read_unlock(); if (&ptype->list == head) goto normal; same_flow = NAPI_GRO_CB(skb)->same_flow; ret = NAPI_GRO_CB(skb)->free ? GRO_MERGED_FREE : GRO_MERGED; if (pp) { struct sk_buff *nskb = *pp; *pp = nskb->next; nskb->next = NULL; napi_gro_complete(nskb); napi->gro_count--; } if (same_flow) goto ok; if (NAPI_GRO_CB(skb)->flush) goto normal; if (unlikely(napi->gro_count >= MAX_GRO_SKBS)) { struct sk_buff *nskb = napi->gro_list; /* locate the end of the list to select the 'oldest' flow */ while (nskb->next) { pp = &nskb->next; nskb = *pp; } *pp = NULL; nskb->next = NULL; napi_gro_complete(nskb); } else { napi->gro_count++; } NAPI_GRO_CB(skb)->count = 1; NAPI_GRO_CB(skb)->age = jiffies; NAPI_GRO_CB(skb)->last = skb; skb_shinfo(skb)->gso_size = skb_gro_len(skb); skb->next = napi->gro_list; napi->gro_list = skb; ret = GRO_HELD; pull: grow = skb_gro_offset(skb) - skb_headlen(skb); if (grow > 0) gro_pull_from_frag0(skb, grow); ok: return ret; normal: ret = GRO_NORMAL; goto pull; } struct packet_offload *gro_find_receive_by_type(__be16 type) { struct list_head *offload_head = &offload_base; struct packet_offload *ptype; list_for_each_entry_rcu(ptype, offload_head, list) { if (ptype->type != type || !ptype->callbacks.gro_receive) continue; return ptype; } return NULL; } EXPORT_SYMBOL(gro_find_receive_by_type); struct packet_offload *gro_find_complete_by_type(__be16 type) { struct list_head *offload_head = &offload_base; struct packet_offload *ptype; list_for_each_entry_rcu(ptype, offload_head, list) { if (ptype->type != type || !ptype->callbacks.gro_complete) continue; return ptype; } return NULL; } EXPORT_SYMBOL(gro_find_complete_by_type); static void napi_skb_free_stolen_head(struct sk_buff *skb) { skb_dst_drop(skb); kmem_cache_free(skbuff_head_cache, skb); } static gro_result_t napi_skb_finish(gro_result_t ret, struct sk_buff *skb) { switch (ret) { case GRO_NORMAL: if (netif_receive_skb_internal(skb)) ret = GRO_DROP; break; case GRO_DROP: kfree_skb(skb); break; case GRO_MERGED_FREE: if (NAPI_GRO_CB(skb)->free == NAPI_GRO_FREE_STOLEN_HEAD) napi_skb_free_stolen_head(skb); else __kfree_skb(skb); break; case GRO_HELD: case GRO_MERGED: break; } return ret; } gro_result_t napi_gro_receive(struct napi_struct *napi, struct sk_buff *skb) { skb_mark_napi_id(skb, napi); trace_napi_gro_receive_entry(skb); skb_gro_reset_offset(skb); return napi_skb_finish(dev_gro_receive(napi, skb), skb); } EXPORT_SYMBOL(napi_gro_receive); static void napi_reuse_skb(struct napi_struct *napi, struct sk_buff *skb) { if (unlikely(skb->pfmemalloc)) { consume_skb(skb); return; } __skb_pull(skb, skb_headlen(skb)); /* restore the reserve we had after netdev_alloc_skb_ip_align() */ skb_reserve(skb, NET_SKB_PAD + NET_IP_ALIGN - skb_headroom(skb)); skb->vlan_tci = 0; skb->dev = napi->dev; skb->skb_iif = 0; /* eth_type_trans() assumes pkt_type is PACKET_HOST */ skb->pkt_type = PACKET_HOST; skb->encapsulation = 0; skb_shinfo(skb)->gso_type = 0; skb->truesize = SKB_TRUESIZE(skb_end_offset(skb)); napi->skb = skb; } struct sk_buff *napi_get_frags(struct napi_struct *napi) { struct sk_buff *skb = napi->skb; if (!skb) { skb = napi_alloc_skb(napi, GRO_MAX_HEAD); if (skb) { napi->skb = skb; skb_mark_napi_id(skb, napi); } } return skb; } EXPORT_SYMBOL(napi_get_frags); static gro_result_t napi_frags_finish(struct napi_struct *napi, struct sk_buff *skb, gro_result_t ret) { switch (ret) { case GRO_NORMAL: case GRO_HELD: __skb_push(skb, ETH_HLEN); skb->protocol = eth_type_trans(skb, skb->dev); if (ret == GRO_NORMAL && netif_receive_skb_internal(skb)) ret = GRO_DROP; break; case GRO_DROP: napi_reuse_skb(napi, skb); break; case GRO_MERGED_FREE: if (NAPI_GRO_CB(skb)->free == NAPI_GRO_FREE_STOLEN_HEAD) napi_skb_free_stolen_head(skb); else napi_reuse_skb(napi, skb); break; case GRO_MERGED: break; } return ret; } /* Upper GRO stack assumes network header starts at gro_offset=0 * Drivers could call both napi_gro_frags() and napi_gro_receive() * We copy ethernet header into skb->data to have a common layout. */ static struct sk_buff *napi_frags_skb(struct napi_struct *napi) { struct sk_buff *skb = napi->skb; const struct ethhdr *eth; unsigned int hlen = sizeof(*eth); napi->skb = NULL; skb_reset_mac_header(skb); skb_gro_reset_offset(skb); if (unlikely(skb_gro_header_hard(skb, hlen))) { eth = skb_gro_header_slow(skb, hlen, 0); if (unlikely(!eth)) { net_warn_ratelimited("%s: dropping impossible skb from %s\n", __func__, napi->dev->name); napi_reuse_skb(napi, skb); return NULL; } } else { eth = (const struct ethhdr *)skb->data; gro_pull_from_frag0(skb, hlen); NAPI_GRO_CB(skb)->frag0 += hlen; NAPI_GRO_CB(skb)->frag0_len -= hlen; } __skb_pull(skb, hlen); /* * This works because the only protocols we care about don't require * special handling. * We'll fix it up properly in napi_frags_finish() */ skb->protocol = eth->h_proto; return skb; } gro_result_t napi_gro_frags(struct napi_struct *napi) { struct sk_buff *skb = napi_frags_skb(napi); if (!skb) return GRO_DROP; trace_napi_gro_frags_entry(skb); return napi_frags_finish(napi, skb, dev_gro_receive(napi, skb)); } EXPORT_SYMBOL(napi_gro_frags); /* Compute the checksum from gro_offset and return the folded value * after adding in any pseudo checksum. */ __sum16 __skb_gro_checksum_complete(struct sk_buff *skb) { __wsum wsum; __sum16 sum; wsum = skb_checksum(skb, skb_gro_offset(skb), skb_gro_len(skb), 0); /* NAPI_GRO_CB(skb)->csum holds pseudo checksum */ sum = csum_fold(csum_add(NAPI_GRO_CB(skb)->csum, wsum)); if (likely(!sum)) { if (unlikely(skb->ip_summed == CHECKSUM_COMPLETE) && !skb->csum_complete_sw) netdev_rx_csum_fault(skb->dev); } NAPI_GRO_CB(skb)->csum = wsum; NAPI_GRO_CB(skb)->csum_valid = 1; return sum; } EXPORT_SYMBOL(__skb_gro_checksum_complete); static void net_rps_send_ipi(struct softnet_data *remsd) { #ifdef CONFIG_RPS while (remsd) { struct softnet_data *next = remsd->rps_ipi_next; if (cpu_online(remsd->cpu)) { smp_call_function_single_async(remsd->cpu, &remsd->csd); } else { rps_lock(remsd); remsd->backlog.state = 0; rps_unlock(remsd); } remsd = next; } #endif } /* * net_rps_action_and_irq_enable sends any pending IPI's for rps. * Note: called with local irq disabled, but exits with local irq enabled. */ static void net_rps_action_and_irq_enable(struct softnet_data *sd) { #ifdef CONFIG_RPS struct softnet_data *remsd = sd->rps_ipi_list; if (remsd) { sd->rps_ipi_list = NULL; local_irq_enable(); /* Send pending IPI's to kick RPS processing on remote cpus. */ net_rps_send_ipi(remsd); } else #endif local_irq_enable(); } static bool sd_has_rps_ipi_waiting(struct softnet_data *sd) { #ifdef CONFIG_RPS return sd->rps_ipi_list != NULL; #else return false; #endif } static int process_backlog(struct napi_struct *napi, int quota) { struct softnet_data *sd = container_of(napi, struct softnet_data, backlog); bool again = true; int work = 0; /* Check if we have pending ipi, its better to send them now, * not waiting net_rx_action() end. */ if (sd_has_rps_ipi_waiting(sd)) { local_irq_disable(); net_rps_action_and_irq_enable(sd); } napi->weight = weight_p; while (again) { struct sk_buff *skb; while ((skb = __skb_dequeue(&sd->process_queue))) { rcu_read_lock(); __netif_receive_skb(skb); rcu_read_unlock(); input_queue_head_incr(sd); if (++work >= quota) goto state_changed; } local_irq_disable(); rps_lock(sd); if (skb_queue_empty(&sd->input_pkt_queue)) { /* * Inline a custom version of __napi_complete(). * only current cpu owns and manipulates this napi, * and NAPI_STATE_SCHED is the only possible flag set * on backlog. * We can use a plain write instead of clear_bit(), * and we dont need an smp_mb() memory barrier. */ napi->state = 0; again = false; } else { skb_queue_splice_tail_init(&sd->input_pkt_queue, &sd->process_queue); } rps_unlock(sd); local_irq_enable(); } state_changed: napi_gro_flush(napi, false); sd->current_napi = NULL; return work; } /** * __napi_schedule - schedule for receive * @n: entry to schedule * * The entry's receive function will be scheduled to run. * Consider using __napi_schedule_irqoff() if hard irqs are masked. */ void __napi_schedule(struct napi_struct *n) { unsigned long flags; local_irq_save(flags); ____napi_schedule(this_cpu_ptr(&softnet_data), n); local_irq_restore(flags); } EXPORT_SYMBOL(__napi_schedule); /** * __napi_schedule_irqoff - schedule for receive * @n: entry to schedule * * Variant of __napi_schedule() assuming hard irqs are masked. * * On PREEMPT_RT enabled kernels this maps to __napi_schedule() * because the interrupt disabled assumption might not be true * due to force-threaded interrupts and spinlock substitution. */ void __napi_schedule_irqoff(struct napi_struct *n) { if (!IS_ENABLED(CONFIG_PREEMPT_RT)) ____napi_schedule(this_cpu_ptr(&softnet_data), n); else __napi_schedule(n); } EXPORT_SYMBOL(__napi_schedule_irqoff); void __napi_complete(struct napi_struct *n) { struct softnet_data *sd = this_cpu_ptr(&softnet_data); BUG_ON(!test_bit(NAPI_STATE_SCHED, &n->state)); list_del_init(&n->poll_list); smp_mb__before_atomic(); sd->current_napi = NULL; clear_bit(NAPI_STATE_SCHED, &n->state); } EXPORT_SYMBOL(__napi_complete); void napi_complete_done(struct napi_struct *n, int work_done) { unsigned long flags; /* * don't let napi dequeue from the cpu poll list * just in case its running on a different cpu */ if (unlikely(test_bit(NAPI_STATE_NPSVC, &n->state))) return; if (n->gro_list) { unsigned long timeout = 0; if (work_done) timeout = n->dev->gro_flush_timeout; if (timeout) hrtimer_start(&n->timer, ns_to_ktime(timeout), HRTIMER_MODE_REL_PINNED); else napi_gro_flush(n, false); } if (likely(list_empty(&n->poll_list))) { WARN_ON_ONCE(!test_and_clear_bit(NAPI_STATE_SCHED, &n->state)); } else { /* If n->poll_list is not empty, we need to mask irqs */ local_irq_save(flags); __napi_complete(n); local_irq_restore(flags); } } EXPORT_SYMBOL(napi_complete_done); /* must be called under rcu_read_lock(), as we dont take a reference */ static struct napi_struct *napi_by_id(unsigned int napi_id) { unsigned int hash = napi_id % HASH_SIZE(napi_hash); struct napi_struct *napi; hlist_for_each_entry_rcu(napi, &napi_hash[hash], napi_hash_node) if (napi->napi_id == napi_id) return napi; return NULL; } #if defined(CONFIG_NET_RX_BUSY_POLL) #define BUSY_POLL_BUDGET 8 bool sk_busy_loop(struct sock *sk, int nonblock) { unsigned long end_time = !nonblock ? sk_busy_loop_end_time(sk) : 0; int (*busy_poll)(struct napi_struct *dev); struct napi_struct *napi; int rc = false; rcu_read_lock(); napi = napi_by_id(sk->sk_napi_id); if (!napi) goto out; /* Note: ndo_busy_poll method is optional in linux-4.5 */ if (napi->dev->netdev_ops) busy_poll = napi->dev->netdev_ops->ndo_busy_poll; else busy_poll = NULL; do { rc = 0; local_bh_disable(); if (busy_poll) { rc = busy_poll(napi); } else if (napi_schedule_prep(napi)) { void *have = netpoll_poll_lock(napi); if (test_bit(NAPI_STATE_SCHED, &napi->state)) { rc = napi->poll(napi, BUSY_POLL_BUDGET); trace_napi_poll(napi, rc, BUSY_POLL_BUDGET); if (rc == BUSY_POLL_BUDGET) { napi_complete_done(napi, rc); napi_schedule(napi); } } netpoll_poll_unlock(have); } if (rc > 0) __NET_ADD_STATS(sock_net(sk), LINUX_MIB_BUSYPOLLRXPACKETS, rc); local_bh_enable(); if (rc == LL_FLUSH_FAILED) break; /* permanent failure */ cpu_relax(); } while (!nonblock && skb_queue_empty(&sk->sk_receive_queue) && !need_resched() && !busy_loop_timeout(end_time)); rc = !skb_queue_empty(&sk->sk_receive_queue); out: rcu_read_unlock(); return rc; } EXPORT_SYMBOL(sk_busy_loop); #endif /* CONFIG_NET_RX_BUSY_POLL */ void napi_hash_add(struct napi_struct *napi) { if (test_bit(NAPI_STATE_NO_BUSY_POLL, &napi->state) || test_and_set_bit(NAPI_STATE_HASHED, &napi->state)) return; spin_lock(&napi_hash_lock); /* 0..NR_CPUS+1 range is reserved for sender_cpu use */ do { if (unlikely(++napi_gen_id < NR_CPUS + 1)) napi_gen_id = NR_CPUS + 1; } while (napi_by_id(napi_gen_id)); napi->napi_id = napi_gen_id; hlist_add_head_rcu(&napi->napi_hash_node, &napi_hash[napi->napi_id % HASH_SIZE(napi_hash)]); spin_unlock(&napi_hash_lock); } EXPORT_SYMBOL_GPL(napi_hash_add); /* Warning : caller is responsible to make sure rcu grace period * is respected before freeing memory containing @napi */ bool napi_hash_del(struct napi_struct *napi) { bool rcu_sync_needed = false; spin_lock(&napi_hash_lock); if (test_and_clear_bit(NAPI_STATE_HASHED, &napi->state)) { rcu_sync_needed = true; hlist_del_rcu(&napi->napi_hash_node); } spin_unlock(&napi_hash_lock); return rcu_sync_needed; } EXPORT_SYMBOL_GPL(napi_hash_del); static enum hrtimer_restart napi_watchdog(struct hrtimer *timer) { struct napi_struct *napi; napi = container_of(timer, struct napi_struct, timer); if (napi->gro_list) napi_schedule(napi); return HRTIMER_NORESTART; } void netif_napi_add(struct net_device *dev, struct napi_struct *napi, int (*poll)(struct napi_struct *, int), int weight) { INIT_LIST_HEAD(&napi->poll_list); hrtimer_init(&napi->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_PINNED); napi->timer.function = napi_watchdog; napi->gro_count = 0; napi->gro_list = NULL; napi->skb = NULL; napi->poll = poll; if (weight > NAPI_POLL_WEIGHT) pr_err_once("netif_napi_add() called with weight %d on device %s\n", weight, dev->name); napi->weight = weight; napi->dev = dev; #ifdef CONFIG_NETPOLL spin_lock_init(&napi->poll_lock); napi->poll_owner = -1; #endif set_bit(NAPI_STATE_SCHED, &napi->state); set_bit(NAPI_STATE_NPSVC, &napi->state); list_add_rcu(&napi->dev_list, &dev->napi_list); napi_hash_add(napi); } EXPORT_SYMBOL(netif_napi_add); void napi_disable(struct napi_struct *n) { might_sleep(); set_bit(NAPI_STATE_DISABLE, &n->state); while (test_and_set_bit(NAPI_STATE_SCHED, &n->state)) msleep(1); while (test_and_set_bit(NAPI_STATE_NPSVC, &n->state)) msleep(1); hrtimer_cancel(&n->timer); clear_bit(NAPI_STATE_DISABLE, &n->state); } EXPORT_SYMBOL(napi_disable); /* Must be called in process context */ void netif_napi_del(struct napi_struct *napi) { might_sleep(); if (napi_hash_del(napi)) synchronize_net(); list_del_init(&napi->dev_list); napi_free_frags(napi); kfree_skb_list(napi->gro_list); napi->gro_list = NULL; napi->gro_count = 0; } EXPORT_SYMBOL(netif_napi_del); struct napi_struct *get_current_napi_context(void) { struct softnet_data *sd = this_cpu_ptr(&softnet_data); return sd->current_napi; } EXPORT_SYMBOL(get_current_napi_context); static int napi_poll(struct napi_struct *n, struct list_head *repoll) { void *have; int work, weight; list_del_init(&n->poll_list); have = netpoll_poll_lock(n); weight = n->weight; /* This NAPI_STATE_SCHED test is for avoiding a race * with netpoll's poll_napi(). Only the entity which * obtains the lock and sees NAPI_STATE_SCHED set will * actually make the ->poll() call. Therefore we avoid * accidentally calling ->poll() when NAPI is not scheduled. */ work = 0; if (test_bit(NAPI_STATE_SCHED, &n->state)) { struct softnet_data *sd = this_cpu_ptr(&softnet_data); sd->current_napi = n; work = n->poll(n, weight); trace_napi_poll(n, work, weight); } WARN_ON_ONCE(work > weight); if (likely(work < weight)) goto out_unlock; /* Drivers must not modify the NAPI state if they * consume the entire weight. In such cases this code * still "owns" the NAPI instance and therefore can * move the instance around on the list at-will. */ if (unlikely(napi_disable_pending(n))) { napi_complete(n); goto out_unlock; } if (n->gro_list) { /* flush too old packets * If HZ < 1000, flush all packets. */ napi_gro_flush(n, HZ >= 1000); } /* Some drivers may have called napi_schedule * prior to exhausting their budget. */ if (unlikely(!list_empty(&n->poll_list))) { pr_warn_once("%s: Budget exhausted after napi rescheduled\n", n->dev ? n->dev->name : "backlog"); goto out_unlock; } list_add_tail(&n->poll_list, repoll); out_unlock: netpoll_poll_unlock(have); return work; } static __latent_entropy void net_rx_action(struct softirq_action *h) { struct softnet_data *sd = this_cpu_ptr(&softnet_data); unsigned long time_limit = jiffies + 2; int budget = netdev_budget; LIST_HEAD(list); LIST_HEAD(repoll); local_irq_disable(); list_splice_init(&sd->poll_list, &list); local_irq_enable(); for (;;) { struct napi_struct *n; if (list_empty(&list)) { if (!sd_has_rps_ipi_waiting(sd) && list_empty(&repoll)) return; break; } n = list_first_entry(&list, struct napi_struct, poll_list); budget -= napi_poll(n, &repoll); /* If softirq window is exhausted then punt. * Allow this to run for 2 jiffies since which will allow * an average latency of 1.5/HZ. */ if (unlikely(budget <= 0 || time_after_eq(jiffies, time_limit))) { sd->time_squeeze++; break; } } __kfree_skb_flush(); local_irq_disable(); list_splice_tail_init(&sd->poll_list, &list); list_splice_tail(&repoll, &list); list_splice(&list, &sd->poll_list); if (!list_empty(&sd->poll_list)) __raise_softirq_irqoff(NET_RX_SOFTIRQ); net_rps_action_and_irq_enable(sd); } struct netdev_adjacent { struct net_device *dev; /* upper master flag, there can only be one master device per list */ bool master; /* counter for the number of times this device was added to us */ u16 ref_nr; /* private field for the users */ void *private; struct list_head list; struct rcu_head rcu; }; static struct netdev_adjacent *__netdev_find_adj(struct net_device *adj_dev, struct list_head *adj_list) { struct netdev_adjacent *adj; list_for_each_entry(adj, adj_list, list) { if (adj->dev == adj_dev) return adj; } return NULL; } /** * netdev_has_upper_dev - Check if device is linked to an upper device * @dev: device * @upper_dev: upper device to check * * Find out if a device is linked to specified upper device and return true * in case it is. Note that this checks only immediate upper device, * not through a complete stack of devices. The caller must hold the RTNL lock. */ bool netdev_has_upper_dev(struct net_device *dev, struct net_device *upper_dev) { ASSERT_RTNL(); return __netdev_find_adj(upper_dev, &dev->all_adj_list.upper); } EXPORT_SYMBOL(netdev_has_upper_dev); /** * netdev_has_any_upper_dev - Check if device is linked to some device * @dev: device * * Find out if a device is linked to an upper device and return true in case * it is. The caller must hold the RTNL lock. */ bool netdev_has_any_upper_dev(struct net_device *dev) { ASSERT_RTNL(); return !list_empty(&dev->all_adj_list.upper); } EXPORT_SYMBOL(netdev_has_any_upper_dev); /** * netdev_master_upper_dev_get - Get master upper device * @dev: device * * Find a master upper device and return pointer to it or NULL in case * it's not there. The caller must hold the RTNL lock. */ struct net_device *netdev_master_upper_dev_get(struct net_device *dev) { struct netdev_adjacent *upper; ASSERT_RTNL(); if (list_empty(&dev->adj_list.upper)) return NULL; upper = list_first_entry(&dev->adj_list.upper, struct netdev_adjacent, list); if (likely(upper->master)) return upper->dev; return NULL; } EXPORT_SYMBOL(netdev_master_upper_dev_get); void *netdev_adjacent_get_private(struct list_head *adj_list) { struct netdev_adjacent *adj; adj = list_entry(adj_list, struct netdev_adjacent, list); return adj->private; } EXPORT_SYMBOL(netdev_adjacent_get_private); /** * netdev_upper_get_next_dev_rcu - Get the next dev from upper list * @dev: device * @iter: list_head ** of the current position * * Gets the next device from the dev's upper list, starting from iter * position. The caller must hold RCU read lock. */ struct net_device *netdev_upper_get_next_dev_rcu(struct net_device *dev, struct list_head **iter) { struct netdev_adjacent *upper; WARN_ON_ONCE(!rcu_read_lock_held() && !lockdep_rtnl_is_held()); upper = list_entry_rcu((*iter)->next, struct netdev_adjacent, list); if (&upper->list == &dev->adj_list.upper) return NULL; *iter = &upper->list; return upper->dev; } EXPORT_SYMBOL(netdev_upper_get_next_dev_rcu); /** * netdev_all_upper_get_next_dev_rcu - Get the next dev from upper list * @dev: device * @iter: list_head ** of the current position * * Gets the next device from the dev's upper list, starting from iter * position. The caller must hold RCU read lock. */ struct net_device *netdev_all_upper_get_next_dev_rcu(struct net_device *dev, struct list_head **iter) { struct netdev_adjacent *upper; WARN_ON_ONCE(!rcu_read_lock_held() && !lockdep_rtnl_is_held()); upper = list_entry_rcu((*iter)->next, struct netdev_adjacent, list); if (&upper->list == &dev->all_adj_list.upper) return NULL; *iter = &upper->list; return upper->dev; } EXPORT_SYMBOL(netdev_all_upper_get_next_dev_rcu); /** * netdev_lower_get_next_private - Get the next ->private from the * lower neighbour list * @dev: device * @iter: list_head ** of the current position * * Gets the next netdev_adjacent->private from the dev's lower neighbour * list, starting from iter position. The caller must hold either hold the * RTNL lock or its own locking that guarantees that the neighbour lower * list will remain unchanged. */ void *netdev_lower_get_next_private(struct net_device *dev, struct list_head **iter) { struct netdev_adjacent *lower; lower = list_entry(*iter, struct netdev_adjacent, list); if (&lower->list == &dev->adj_list.lower) return NULL; *iter = lower->list.next; return lower->private; } EXPORT_SYMBOL(netdev_lower_get_next_private); /** * netdev_lower_get_next_private_rcu - Get the next ->private from the * lower neighbour list, RCU * variant * @dev: device * @iter: list_head ** of the current position * * Gets the next netdev_adjacent->private from the dev's lower neighbour * list, starting from iter position. The caller must hold RCU read lock. */ void *netdev_lower_get_next_private_rcu(struct net_device *dev, struct list_head **iter) { struct netdev_adjacent *lower; WARN_ON_ONCE(!rcu_read_lock_held()); lower = list_entry_rcu((*iter)->next, struct netdev_adjacent, list); if (&lower->list == &dev->adj_list.lower) return NULL; *iter = &lower->list; return lower->private; } EXPORT_SYMBOL(netdev_lower_get_next_private_rcu); /** * netdev_lower_get_next - Get the next device from the lower neighbour * list * @dev: device * @iter: list_head ** of the current position * * Gets the next netdev_adjacent from the dev's lower neighbour * list, starting from iter position. The caller must hold RTNL lock or * its own locking that guarantees that the neighbour lower * list will remain unchanged. */ void *netdev_lower_get_next(struct net_device *dev, struct list_head **iter) { struct netdev_adjacent *lower; lower = list_entry(*iter, struct netdev_adjacent, list); if (&lower->list == &dev->adj_list.lower) return NULL; *iter = lower->list.next; return lower->dev; } EXPORT_SYMBOL(netdev_lower_get_next); /** * netdev_all_lower_get_next - Get the next device from all lower neighbour list * @dev: device * @iter: list_head ** of the current position * * Gets the next netdev_adjacent from the dev's all lower neighbour * list, starting from iter position. The caller must hold RTNL lock or * its own locking that guarantees that the neighbour all lower * list will remain unchanged. */ struct net_device *netdev_all_lower_get_next(struct net_device *dev, struct list_head **iter) { struct netdev_adjacent *lower; lower = list_entry(*iter, struct netdev_adjacent, list); if (&lower->list == &dev->all_adj_list.lower) return NULL; *iter = lower->list.next; return lower->dev; } EXPORT_SYMBOL(netdev_all_lower_get_next); /** * netdev_all_lower_get_next_rcu - Get the next device from all * lower neighbour list, RCU variant * @dev: device * @iter: list_head ** of the current position * * Gets the next netdev_adjacent from the dev's all lower neighbour * list, starting from iter position. The caller must hold RCU read lock. */ struct net_device *netdev_all_lower_get_next_rcu(struct net_device *dev, struct list_head **iter) { struct netdev_adjacent *lower; lower = list_entry_rcu((*iter)->next, struct netdev_adjacent, list); if (&lower->list == &dev->all_adj_list.lower) return NULL; *iter = &lower->list; return lower->dev; } EXPORT_SYMBOL(netdev_all_lower_get_next_rcu); /** * netdev_lower_get_first_private_rcu - Get the first ->private from the * lower neighbour list, RCU * variant * @dev: device * * Gets the first netdev_adjacent->private from the dev's lower neighbour * list. The caller must hold RCU read lock. */ void *netdev_lower_get_first_private_rcu(struct net_device *dev) { struct netdev_adjacent *lower; lower = list_first_or_null_rcu(&dev->adj_list.lower, struct netdev_adjacent, list); if (lower) return lower->private; return NULL; } EXPORT_SYMBOL(netdev_lower_get_first_private_rcu); /** * netdev_master_upper_dev_get_rcu - Get master upper device * @dev: device * * Find a master upper device and return pointer to it or NULL in case * it's not there. The caller must hold the RCU read lock. */ struct net_device *netdev_master_upper_dev_get_rcu(struct net_device *dev) { struct netdev_adjacent *upper; upper = list_first_or_null_rcu(&dev->adj_list.upper, struct netdev_adjacent, list); if (upper && likely(upper->master)) return upper->dev; return NULL; } EXPORT_SYMBOL(netdev_master_upper_dev_get_rcu); static int netdev_adjacent_sysfs_add(struct net_device *dev, struct net_device *adj_dev, struct list_head *dev_list) { char linkname[IFNAMSIZ+7]; sprintf(linkname, dev_list == &dev->adj_list.upper ? "upper_%s" : "lower_%s", adj_dev->name); return sysfs_create_link(&(dev->dev.kobj), &(adj_dev->dev.kobj), linkname); } static void netdev_adjacent_sysfs_del(struct net_device *dev, char *name, struct list_head *dev_list) { char linkname[IFNAMSIZ+7]; sprintf(linkname, dev_list == &dev->adj_list.upper ? "upper_%s" : "lower_%s", name); sysfs_remove_link(&(dev->dev.kobj), linkname); } static inline bool netdev_adjacent_is_neigh_list(struct net_device *dev, struct net_device *adj_dev, struct list_head *dev_list) { return (dev_list == &dev->adj_list.upper || dev_list == &dev->adj_list.lower) && net_eq(dev_net(dev), dev_net(adj_dev)); } static int __netdev_adjacent_dev_insert(struct net_device *dev, struct net_device *adj_dev, u16 ref_nr, struct list_head *dev_list, void *private, bool master) { struct netdev_adjacent *adj; int ret; adj = __netdev_find_adj(adj_dev, dev_list); if (adj) { adj->ref_nr += ref_nr; return 0; } adj = kmalloc(sizeof(*adj), GFP_KERNEL); if (!adj) return -ENOMEM; adj->dev = adj_dev; adj->master = master; adj->ref_nr = ref_nr; adj->private = private; dev_hold(adj_dev); pr_debug("dev_hold for %s, because of link added from %s to %s\n", adj_dev->name, dev->name, adj_dev->name); if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list)) { ret = netdev_adjacent_sysfs_add(dev, adj_dev, dev_list); if (ret) goto free_adj; } /* Ensure that master link is always the first item in list. */ if (master) { ret = sysfs_create_link(&(dev->dev.kobj), &(adj_dev->dev.kobj), "master"); if (ret) goto remove_symlinks; list_add_rcu(&adj->list, dev_list); } else { list_add_tail_rcu(&adj->list, dev_list); } return 0; remove_symlinks: if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list)) netdev_adjacent_sysfs_del(dev, adj_dev->name, dev_list); free_adj: kfree(adj); dev_put(adj_dev); return ret; } static void __netdev_adjacent_dev_remove(struct net_device *dev, struct net_device *adj_dev, u16 ref_nr, struct list_head *dev_list) { struct netdev_adjacent *adj; adj = __netdev_find_adj(adj_dev, dev_list); if (!adj) { pr_err("tried to remove device %s from %s\n", dev->name, adj_dev->name); BUG(); } if (adj->ref_nr > ref_nr) { pr_debug("%s to %s ref_nr-%d = %d\n", dev->name, adj_dev->name, ref_nr, adj->ref_nr-ref_nr); adj->ref_nr -= ref_nr; return; } if (adj->master) sysfs_remove_link(&(dev->dev.kobj), "master"); if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list)) netdev_adjacent_sysfs_del(dev, adj_dev->name, dev_list); list_del_rcu(&adj->list); pr_debug("dev_put for %s, because link removed from %s to %s\n", adj_dev->name, dev->name, adj_dev->name); dev_put(adj_dev); kfree_rcu(adj, rcu); } static int __netdev_adjacent_dev_link_lists(struct net_device *dev, struct net_device *upper_dev, u16 ref_nr, struct list_head *up_list, struct list_head *down_list, void *private, bool master) { int ret; ret = __netdev_adjacent_dev_insert(dev, upper_dev, ref_nr, up_list, private, master); if (ret) return ret; ret = __netdev_adjacent_dev_insert(upper_dev, dev, ref_nr, down_list, private, false); if (ret) { __netdev_adjacent_dev_remove(dev, upper_dev, ref_nr, up_list); return ret; } return 0; } static int __netdev_adjacent_dev_link(struct net_device *dev, struct net_device *upper_dev, u16 ref_nr) { return __netdev_adjacent_dev_link_lists(dev, upper_dev, ref_nr, &dev->all_adj_list.upper, &upper_dev->all_adj_list.lower, NULL, false); } static void __netdev_adjacent_dev_unlink_lists(struct net_device *dev, struct net_device *upper_dev, u16 ref_nr, struct list_head *up_list, struct list_head *down_list) { __netdev_adjacent_dev_remove(dev, upper_dev, ref_nr, up_list); __netdev_adjacent_dev_remove(upper_dev, dev, ref_nr, down_list); } static void __netdev_adjacent_dev_unlink(struct net_device *dev, struct net_device *upper_dev, u16 ref_nr) { __netdev_adjacent_dev_unlink_lists(dev, upper_dev, ref_nr, &dev->all_adj_list.upper, &upper_dev->all_adj_list.lower); } static int __netdev_adjacent_dev_link_neighbour(struct net_device *dev, struct net_device *upper_dev, void *private, bool master) { int ret = __netdev_adjacent_dev_link(dev, upper_dev, 1); if (ret) return ret; ret = __netdev_adjacent_dev_link_lists(dev, upper_dev, 1, &dev->adj_list.upper, &upper_dev->adj_list.lower, private, master); if (ret) { __netdev_adjacent_dev_unlink(dev, upper_dev, 1); return ret; } return 0; } static void __netdev_adjacent_dev_unlink_neighbour(struct net_device *dev, struct net_device *upper_dev) { __netdev_adjacent_dev_unlink(dev, upper_dev, 1); __netdev_adjacent_dev_unlink_lists(dev, upper_dev, 1, &dev->adj_list.upper, &upper_dev->adj_list.lower); } static int __netdev_upper_dev_link(struct net_device *dev, struct net_device *upper_dev, bool master, void *upper_priv, void *upper_info) { struct netdev_notifier_changeupper_info changeupper_info; struct netdev_adjacent *i, *j, *to_i, *to_j; int ret = 0; ASSERT_RTNL(); if (dev == upper_dev) return -EBUSY; /* To prevent loops, check if dev is not upper device to upper_dev. */ if (__netdev_find_adj(dev, &upper_dev->all_adj_list.upper)) return -EBUSY; if (__netdev_find_adj(upper_dev, &dev->adj_list.upper)) return -EEXIST; if (master && netdev_master_upper_dev_get(dev)) return -EBUSY; changeupper_info.upper_dev = upper_dev; changeupper_info.master = master; changeupper_info.linking = true; changeupper_info.upper_info = upper_info; ret = call_netdevice_notifiers_info(NETDEV_PRECHANGEUPPER, dev, &changeupper_info.info); ret = notifier_to_errno(ret); if (ret) return ret; ret = __netdev_adjacent_dev_link_neighbour(dev, upper_dev, upper_priv, master); if (ret) return ret; /* Now that we linked these devs, make all the upper_dev's * all_adj_list.upper visible to every dev's all_adj_list.lower an * versa, and don't forget the devices itself. All of these * links are non-neighbours. */ list_for_each_entry(i, &dev->all_adj_list.lower, list) { list_for_each_entry(j, &upper_dev->all_adj_list.upper, list) { pr_debug("Interlinking %s with %s, non-neighbour\n", i->dev->name, j->dev->name); ret = __netdev_adjacent_dev_link(i->dev, j->dev, i->ref_nr); if (ret) goto rollback_mesh; } } /* add dev to every upper_dev's upper device */ list_for_each_entry(i, &upper_dev->all_adj_list.upper, list) { pr_debug("linking %s's upper device %s with %s\n", upper_dev->name, i->dev->name, dev->name); ret = __netdev_adjacent_dev_link(dev, i->dev, i->ref_nr); if (ret) goto rollback_upper_mesh; } /* add upper_dev to every dev's lower device */ list_for_each_entry(i, &dev->all_adj_list.lower, list) { pr_debug("linking %s's lower device %s with %s\n", dev->name, i->dev->name, upper_dev->name); ret = __netdev_adjacent_dev_link(i->dev, upper_dev, i->ref_nr); if (ret) goto rollback_lower_mesh; } ret = call_netdevice_notifiers_info(NETDEV_CHANGEUPPER, dev, &changeupper_info.info); ret = notifier_to_errno(ret); if (ret) goto rollback_lower_mesh; return 0; rollback_lower_mesh: to_i = i; list_for_each_entry(i, &dev->all_adj_list.lower, list) { if (i == to_i) break; __netdev_adjacent_dev_unlink(i->dev, upper_dev, i->ref_nr); } i = NULL; rollback_upper_mesh: to_i = i; list_for_each_entry(i, &upper_dev->all_adj_list.upper, list) { if (i == to_i) break; __netdev_adjacent_dev_unlink(dev, i->dev, i->ref_nr); } i = j = NULL; rollback_mesh: to_i = i; to_j = j; list_for_each_entry(i, &dev->all_adj_list.lower, list) { list_for_each_entry(j, &upper_dev->all_adj_list.upper, list) { if (i == to_i && j == to_j) break; __netdev_adjacent_dev_unlink(i->dev, j->dev, i->ref_nr); } if (i == to_i) break; } __netdev_adjacent_dev_unlink_neighbour(dev, upper_dev); return ret; } /** * netdev_upper_dev_link - Add a link to the upper device * @dev: device * @upper_dev: new upper device * * Adds a link to device which is upper to this one. The caller must hold * the RTNL lock. On a failure a negative errno code is returned. * On success the reference counts are adjusted and the function * returns zero. */ int netdev_upper_dev_link(struct net_device *dev, struct net_device *upper_dev) { return __netdev_upper_dev_link(dev, upper_dev, false, NULL, NULL); } EXPORT_SYMBOL(netdev_upper_dev_link); /** * netdev_master_upper_dev_link - Add a master link to the upper device * @dev: device * @upper_dev: new upper device * @upper_priv: upper device private * @upper_info: upper info to be passed down via notifier * * Adds a link to device which is upper to this one. In this case, only * one master upper device can be linked, although other non-master devices * might be linked as well. The caller must hold the RTNL lock. * On a failure a negative errno code is returned. On success the reference * counts are adjusted and the function returns zero. */ int netdev_master_upper_dev_link(struct net_device *dev, struct net_device *upper_dev, void *upper_priv, void *upper_info) { return __netdev_upper_dev_link(dev, upper_dev, true, upper_priv, upper_info); } EXPORT_SYMBOL(netdev_master_upper_dev_link); /** * netdev_upper_dev_unlink - Removes a link to upper device * @dev: device * @upper_dev: new upper device * * Removes a link to device which is upper to this one. The caller must hold * the RTNL lock. */ void netdev_upper_dev_unlink(struct net_device *dev, struct net_device *upper_dev) { struct netdev_notifier_changeupper_info changeupper_info; struct netdev_adjacent *i, *j; ASSERT_RTNL(); changeupper_info.upper_dev = upper_dev; changeupper_info.master = netdev_master_upper_dev_get(dev) == upper_dev; changeupper_info.linking = false; call_netdevice_notifiers_info(NETDEV_PRECHANGEUPPER, dev, &changeupper_info.info); __netdev_adjacent_dev_unlink_neighbour(dev, upper_dev); /* Here is the tricky part. We must remove all dev's lower * devices from all upper_dev's upper devices and vice * versa, to maintain the graph relationship. */ list_for_each_entry(i, &dev->all_adj_list.lower, list) list_for_each_entry(j, &upper_dev->all_adj_list.upper, list) __netdev_adjacent_dev_unlink(i->dev, j->dev, i->ref_nr); /* remove also the devices itself from lower/upper device * list */ list_for_each_entry(i, &dev->all_adj_list.lower, list) __netdev_adjacent_dev_unlink(i->dev, upper_dev, i->ref_nr); list_for_each_entry(i, &upper_dev->all_adj_list.upper, list) __netdev_adjacent_dev_unlink(dev, i->dev, i->ref_nr); call_netdevice_notifiers_info(NETDEV_CHANGEUPPER, dev, &changeupper_info.info); } EXPORT_SYMBOL(netdev_upper_dev_unlink); /** * netdev_bonding_info_change - Dispatch event about slave change * @dev: device * @bonding_info: info to dispatch * * Send NETDEV_BONDING_INFO to netdev notifiers with info. * The caller must hold the RTNL lock. */ void netdev_bonding_info_change(struct net_device *dev, struct netdev_bonding_info *bonding_info) { struct netdev_notifier_bonding_info info; memcpy(&info.bonding_info, bonding_info, sizeof(struct netdev_bonding_info)); call_netdevice_notifiers_info(NETDEV_BONDING_INFO, dev, &info.info); } EXPORT_SYMBOL(netdev_bonding_info_change); static void netdev_adjacent_add_links(struct net_device *dev) { struct netdev_adjacent *iter; struct net *net = dev_net(dev); list_for_each_entry(iter, &dev->adj_list.upper, list) { if (!net_eq(net, dev_net(iter->dev))) continue; netdev_adjacent_sysfs_add(iter->dev, dev, &iter->dev->adj_list.lower); netdev_adjacent_sysfs_add(dev, iter->dev, &dev->adj_list.upper); } list_for_each_entry(iter, &dev->adj_list.lower, list) { if (!net_eq(net, dev_net(iter->dev))) continue; netdev_adjacent_sysfs_add(iter->dev, dev, &iter->dev->adj_list.upper); netdev_adjacent_sysfs_add(dev, iter->dev, &dev->adj_list.lower); } } static void netdev_adjacent_del_links(struct net_device *dev) { struct netdev_adjacent *iter; struct net *net = dev_net(dev); list_for_each_entry(iter, &dev->adj_list.upper, list) { if (!net_eq(net, dev_net(iter->dev))) continue; netdev_adjacent_sysfs_del(iter->dev, dev->name, &iter->dev->adj_list.lower); netdev_adjacent_sysfs_del(dev, iter->dev->name, &dev->adj_list.upper); } list_for_each_entry(iter, &dev->adj_list.lower, list) { if (!net_eq(net, dev_net(iter->dev))) continue; netdev_adjacent_sysfs_del(iter->dev, dev->name, &iter->dev->adj_list.upper); netdev_adjacent_sysfs_del(dev, iter->dev->name, &dev->adj_list.lower); } } void netdev_adjacent_rename_links(struct net_device *dev, char *oldname) { struct netdev_adjacent *iter; struct net *net = dev_net(dev); list_for_each_entry(iter, &dev->adj_list.upper, list) { if (!net_eq(net, dev_net(iter->dev))) continue; netdev_adjacent_sysfs_del(iter->dev, oldname, &iter->dev->adj_list.lower); netdev_adjacent_sysfs_add(iter->dev, dev, &iter->dev->adj_list.lower); } list_for_each_entry(iter, &dev->adj_list.lower, list) { if (!net_eq(net, dev_net(iter->dev))) continue; netdev_adjacent_sysfs_del(iter->dev, oldname, &iter->dev->adj_list.upper); netdev_adjacent_sysfs_add(iter->dev, dev, &iter->dev->adj_list.upper); } } void *netdev_lower_dev_get_private(struct net_device *dev, struct net_device *lower_dev) { struct netdev_adjacent *lower; if (!lower_dev) return NULL; lower = __netdev_find_adj(lower_dev, &dev->adj_list.lower); if (!lower) return NULL; return lower->private; } EXPORT_SYMBOL(netdev_lower_dev_get_private); int dev_get_nest_level(struct net_device *dev) { struct net_device *lower = NULL; struct list_head *iter; int max_nest = -1; int nest; ASSERT_RTNL(); netdev_for_each_lower_dev(dev, lower, iter) { nest = dev_get_nest_level(lower); if (max_nest < nest) max_nest = nest; } return max_nest + 1; } EXPORT_SYMBOL(dev_get_nest_level); /** * netdev_lower_change - Dispatch event about lower device state change * @lower_dev: device * @lower_state_info: state to dispatch * * Send NETDEV_CHANGELOWERSTATE to netdev notifiers with info. * The caller must hold the RTNL lock. */ void netdev_lower_state_changed(struct net_device *lower_dev, void *lower_state_info) { struct netdev_notifier_changelowerstate_info changelowerstate_info; ASSERT_RTNL(); changelowerstate_info.lower_state_info = lower_state_info; call_netdevice_notifiers_info(NETDEV_CHANGELOWERSTATE, lower_dev, &changelowerstate_info.info); } EXPORT_SYMBOL(netdev_lower_state_changed); int netdev_default_l2upper_neigh_construct(struct net_device *dev, struct neighbour *n) { struct net_device *lower_dev, *stop_dev; struct list_head *iter; int err; netdev_for_each_lower_dev(dev, lower_dev, iter) { if (!lower_dev->netdev_ops->ndo_neigh_construct) continue; err = lower_dev->netdev_ops->ndo_neigh_construct(lower_dev, n); if (err) { stop_dev = lower_dev; goto rollback; } } return 0; rollback: netdev_for_each_lower_dev(dev, lower_dev, iter) { if (lower_dev == stop_dev) break; if (!lower_dev->netdev_ops->ndo_neigh_destroy) continue; lower_dev->netdev_ops->ndo_neigh_destroy(lower_dev, n); } return err; } EXPORT_SYMBOL_GPL(netdev_default_l2upper_neigh_construct); void netdev_default_l2upper_neigh_destroy(struct net_device *dev, struct neighbour *n) { struct net_device *lower_dev; struct list_head *iter; netdev_for_each_lower_dev(dev, lower_dev, iter) { if (!lower_dev->netdev_ops->ndo_neigh_destroy) continue; lower_dev->netdev_ops->ndo_neigh_destroy(lower_dev, n); } } EXPORT_SYMBOL_GPL(netdev_default_l2upper_neigh_destroy); static void dev_change_rx_flags(struct net_device *dev, int flags) { const struct net_device_ops *ops = dev->netdev_ops; if (ops->ndo_change_rx_flags) ops->ndo_change_rx_flags(dev, flags); } static int __dev_set_promiscuity(struct net_device *dev, int inc, bool notify) { unsigned int old_flags = dev->flags; kuid_t uid; kgid_t gid; ASSERT_RTNL(); dev->flags |= IFF_PROMISC; dev->promiscuity += inc; if (dev->promiscuity == 0) { /* * Avoid overflow. * If inc causes overflow, untouch promisc and return error. */ if (inc < 0) dev->flags &= ~IFF_PROMISC; else { dev->promiscuity -= inc; pr_warn("%s: promiscuity touches roof, set promiscuity failed. promiscuity feature of device might be broken.\n", dev->name); return -EOVERFLOW; } } if (dev->flags != old_flags) { pr_info("device %s %s promiscuous mode\n", dev->name, dev->flags & IFF_PROMISC ? "entered" : "left"); if (audit_enabled) { current_uid_gid(&uid, &gid); audit_log(audit_context(), GFP_ATOMIC, AUDIT_ANOM_PROMISCUOUS, "dev=%s prom=%d old_prom=%d auid=%u uid=%u gid=%u ses=%u", dev->name, (dev->flags & IFF_PROMISC), (old_flags & IFF_PROMISC), from_kuid(&init_user_ns, audit_get_loginuid(current)), from_kuid(&init_user_ns, uid), from_kgid(&init_user_ns, gid), audit_get_sessionid(current)); } dev_change_rx_flags(dev, IFF_PROMISC); } if (notify) __dev_notify_flags(dev, old_flags, IFF_PROMISC); return 0; } /** * dev_set_promiscuity - update promiscuity count on a device * @dev: device * @inc: modifier * * Add or remove promiscuity from a device. While the count in the device * remains above zero the interface remains promiscuous. Once it hits zero * the device reverts back to normal filtering operation. A negative inc * value is used to drop promiscuity on the device. * Return 0 if successful or a negative errno code on error. */ int dev_set_promiscuity(struct net_device *dev, int inc) { unsigned int old_flags = dev->flags; int err; err = __dev_set_promiscuity(dev, inc, true); if (err < 0) return err; if (dev->flags != old_flags) dev_set_rx_mode(dev); return err; } EXPORT_SYMBOL(dev_set_promiscuity); static int __dev_set_allmulti(struct net_device *dev, int inc, bool notify) { unsigned int old_flags = dev->flags, old_gflags = dev->gflags; ASSERT_RTNL(); dev->flags |= IFF_ALLMULTI; dev->allmulti += inc; if (dev->allmulti == 0) { /* * Avoid overflow. * If inc causes overflow, untouch allmulti and return error. */ if (inc < 0) dev->flags &= ~IFF_ALLMULTI; else { dev->allmulti -= inc; pr_warn("%s: allmulti touches roof, set allmulti failed. allmulti feature of device might be broken.\n", dev->name); return -EOVERFLOW; } } if (dev->flags ^ old_flags) { dev_change_rx_flags(dev, IFF_ALLMULTI); dev_set_rx_mode(dev); if (notify) __dev_notify_flags(dev, old_flags, dev->gflags ^ old_gflags); } return 0; } /** * dev_set_allmulti - update allmulti count on a device * @dev: device * @inc: modifier * * Add or remove reception of all multicast frames to a device. While the * count in the device remains above zero the interface remains listening * to all interfaces. Once it hits zero the device reverts back to normal * filtering operation. A negative @inc value is used to drop the counter * when releasing a resource needing all multicasts. * Return 0 if successful or a negative errno code on error. */ int dev_set_allmulti(struct net_device *dev, int inc) { return __dev_set_allmulti(dev, inc, true); } EXPORT_SYMBOL(dev_set_allmulti); /* * Upload unicast and multicast address lists to device and * configure RX filtering. When the device doesn't support unicast * filtering it is put in promiscuous mode while unicast addresses * are present. */ void __dev_set_rx_mode(struct net_device *dev) { const struct net_device_ops *ops = dev->netdev_ops; /* dev_open will call this function so the list will stay sane. */ if (!(dev->flags&IFF_UP)) return; if (!netif_device_present(dev)) return; if (!(dev->priv_flags & IFF_UNICAST_FLT)) { /* Unicast addresses changes may only happen under the rtnl, * therefore calling __dev_set_promiscuity here is safe. */ if (!netdev_uc_empty(dev) && !dev->uc_promisc) { __dev_set_promiscuity(dev, 1, false); dev->uc_promisc = true; } else if (netdev_uc_empty(dev) && dev->uc_promisc) { __dev_set_promiscuity(dev, -1, false); dev->uc_promisc = false; } } if (ops->ndo_set_rx_mode) ops->ndo_set_rx_mode(dev); } void dev_set_rx_mode(struct net_device *dev) { netif_addr_lock_bh(dev); __dev_set_rx_mode(dev); netif_addr_unlock_bh(dev); } /** * dev_get_flags - get flags reported to userspace * @dev: device * * Get the combination of flag bits exported through APIs to userspace. */ unsigned int dev_get_flags(const struct net_device *dev) { unsigned int flags; flags = (dev->flags & ~(IFF_PROMISC | IFF_ALLMULTI | IFF_RUNNING | IFF_LOWER_UP | IFF_DORMANT)) | (dev->gflags & (IFF_PROMISC | IFF_ALLMULTI)); if (netif_running(dev)) { if (netif_oper_up(dev)) flags |= IFF_RUNNING; if (netif_carrier_ok(dev)) flags |= IFF_LOWER_UP; if (netif_dormant(dev)) flags |= IFF_DORMANT; } return flags; } EXPORT_SYMBOL(dev_get_flags); int __dev_change_flags(struct net_device *dev, unsigned int flags) { unsigned int old_flags = dev->flags; int ret; ASSERT_RTNL(); /* * Set the flags on our device. */ dev->flags = (flags & (IFF_DEBUG | IFF_NOTRAILERS | IFF_NOARP | IFF_DYNAMIC | IFF_MULTICAST | IFF_PORTSEL | IFF_AUTOMEDIA)) | (dev->flags & (IFF_UP | IFF_VOLATILE | IFF_PROMISC | IFF_ALLMULTI)); /* * Load in the correct multicast list now the flags have changed. */ if ((old_flags ^ flags) & IFF_MULTICAST) dev_change_rx_flags(dev, IFF_MULTICAST); dev_set_rx_mode(dev); /* * Have we downed the interface. We handle IFF_UP ourselves * according to user attempts to set it, rather than blindly * setting it. */ ret = 0; if ((old_flags ^ flags) & IFF_UP) ret = ((old_flags & IFF_UP) ? __dev_close : __dev_open)(dev); if ((flags ^ dev->gflags) & IFF_PROMISC) { int inc = (flags & IFF_PROMISC) ? 1 : -1; unsigned int old_flags = dev->flags; dev->gflags ^= IFF_PROMISC; if (__dev_set_promiscuity(dev, inc, false) >= 0) if (dev->flags != old_flags) dev_set_rx_mode(dev); } /* NOTE: order of synchronization of IFF_PROMISC and IFF_ALLMULTI * is important. Some (broken) drivers set IFF_PROMISC, when * IFF_ALLMULTI is requested not asking us and not reporting. */ if ((flags ^ dev->gflags) & IFF_ALLMULTI) { int inc = (flags & IFF_ALLMULTI) ? 1 : -1; dev->gflags ^= IFF_ALLMULTI; __dev_set_allmulti(dev, inc, false); } return ret; } void __dev_notify_flags(struct net_device *dev, unsigned int old_flags, unsigned int gchanges) { unsigned int changes = dev->flags ^ old_flags; if (gchanges) rtmsg_ifinfo(RTM_NEWLINK, dev, gchanges, GFP_ATOMIC); if (changes & IFF_UP) { if (dev->flags & IFF_UP) call_netdevice_notifiers(NETDEV_UP, dev); else call_netdevice_notifiers(NETDEV_DOWN, dev); } if (dev->flags & IFF_UP && (changes & ~(IFF_UP | IFF_PROMISC | IFF_ALLMULTI | IFF_VOLATILE))) { struct netdev_notifier_change_info change_info; change_info.flags_changed = changes; call_netdevice_notifiers_info(NETDEV_CHANGE, dev, &change_info.info); } } /** * dev_change_flags - change device settings * @dev: device * @flags: device state flags * * Change settings on device based state flags. The flags are * in the userspace exported format. */ int dev_change_flags(struct net_device *dev, unsigned int flags) { int ret; unsigned int changes, old_flags = dev->flags, old_gflags = dev->gflags; ret = __dev_change_flags(dev, flags); if (ret < 0) return ret; changes = (old_flags ^ dev->flags) | (old_gflags ^ dev->gflags); __dev_notify_flags(dev, old_flags, changes); return ret; } EXPORT_SYMBOL(dev_change_flags); static int __dev_set_mtu(struct net_device *dev, int new_mtu) { const struct net_device_ops *ops = dev->netdev_ops; if (ops->ndo_change_mtu) return ops->ndo_change_mtu(dev, new_mtu); /* Pairs with all the lockless reads of dev->mtu in the stack */ WRITE_ONCE(dev->mtu, new_mtu); return 0; } /** * dev_set_mtu - Change maximum transfer unit * @dev: device * @new_mtu: new transfer unit * * Change the maximum transfer size of the network device. */ int dev_set_mtu(struct net_device *dev, int new_mtu) { int err, orig_mtu; if (new_mtu == dev->mtu) return 0; /* MTU must be positive. */ if (new_mtu < 0) return -EINVAL; if (!netif_device_present(dev)) return -ENODEV; err = call_netdevice_notifiers(NETDEV_PRECHANGEMTU, dev); err = notifier_to_errno(err); if (err) return err; orig_mtu = dev->mtu; err = __dev_set_mtu(dev, new_mtu); if (!err) { err = call_netdevice_notifiers_mtu(NETDEV_CHANGEMTU, dev, orig_mtu); err = notifier_to_errno(err); if (err) { /* setting mtu back and notifying everyone again, * so that they have a chance to revert changes. */ __dev_set_mtu(dev, orig_mtu); call_netdevice_notifiers_mtu(NETDEV_CHANGEMTU, dev, new_mtu); } } return err; } EXPORT_SYMBOL(dev_set_mtu); /** * dev_set_group - Change group this device belongs to * @dev: device * @new_group: group this device should belong to */ void dev_set_group(struct net_device *dev, int new_group) { dev->group = new_group; } EXPORT_SYMBOL(dev_set_group); /** * dev_set_mac_address - Change Media Access Control Address * @dev: device * @sa: new address * * Change the hardware (MAC) address of the device */ int dev_set_mac_address(struct net_device *dev, struct sockaddr *sa) { const struct net_device_ops *ops = dev->netdev_ops; int err; if (!ops->ndo_set_mac_address) return -EOPNOTSUPP; if (sa->sa_family != dev->type) return -EINVAL; if (!netif_device_present(dev)) return -ENODEV; err = ops->ndo_set_mac_address(dev, sa); if (err) return err; dev->addr_assign_type = NET_ADDR_SET; call_netdevice_notifiers(NETDEV_CHANGEADDR, dev); add_device_randomness(dev->dev_addr, dev->addr_len); return 0; } EXPORT_SYMBOL(dev_set_mac_address); /** * dev_change_carrier - Change device carrier * @dev: device * @new_carrier: new value * * Change device carrier */ int dev_change_carrier(struct net_device *dev, bool new_carrier) { const struct net_device_ops *ops = dev->netdev_ops; if (!ops->ndo_change_carrier) return -EOPNOTSUPP; if (!netif_device_present(dev)) return -ENODEV; return ops->ndo_change_carrier(dev, new_carrier); } EXPORT_SYMBOL(dev_change_carrier); /** * dev_get_phys_port_id - Get device physical port ID * @dev: device * @ppid: port ID * * Get device physical port ID */ int dev_get_phys_port_id(struct net_device *dev, struct netdev_phys_item_id *ppid) { const struct net_device_ops *ops = dev->netdev_ops; if (!ops->ndo_get_phys_port_id) return -EOPNOTSUPP; return ops->ndo_get_phys_port_id(dev, ppid); } EXPORT_SYMBOL(dev_get_phys_port_id); /** * dev_get_phys_port_name - Get device physical port name * @dev: device * @name: port name * @len: limit of bytes to copy to name * * Get device physical port name */ int dev_get_phys_port_name(struct net_device *dev, char *name, size_t len) { const struct net_device_ops *ops = dev->netdev_ops; if (!ops->ndo_get_phys_port_name) return -EOPNOTSUPP; return ops->ndo_get_phys_port_name(dev, name, len); } EXPORT_SYMBOL(dev_get_phys_port_name); /** * dev_change_proto_down - update protocol port state information * @dev: device * @proto_down: new value * * This info can be used by switch drivers to set the phys state of the * port. */ int dev_change_proto_down(struct net_device *dev, bool proto_down) { const struct net_device_ops *ops = dev->netdev_ops; if (!ops->ndo_change_proto_down) return -EOPNOTSUPP; if (!netif_device_present(dev)) return -ENODEV; return ops->ndo_change_proto_down(dev, proto_down); } EXPORT_SYMBOL(dev_change_proto_down); u32 __dev_xdp_query(struct net_device *dev, bpf_op_t bpf_op, enum bpf_netdev_command cmd) { struct netdev_bpf xdp; if (!bpf_op) return 0; memset(&xdp, 0, sizeof(xdp)); xdp.command = cmd; /* Query must always succeed. */ WARN_ON(bpf_op(dev, &xdp) < 0 && cmd == XDP_QUERY_PROG); return xdp.prog_id; } static int dev_xdp_install(struct net_device *dev, bpf_op_t bpf_op, u32 flags, struct bpf_prog *prog) { bool non_hw = !(flags & XDP_FLAGS_HW_MODE); struct bpf_prog *prev_prog = NULL; struct netdev_bpf xdp; int err; if (non_hw) { prev_prog = bpf_prog_by_id(__dev_xdp_query(dev, bpf_op, XDP_QUERY_PROG)); if (IS_ERR(prev_prog)) prev_prog = NULL; } memset(&xdp, 0, sizeof(xdp)); if (flags & XDP_FLAGS_HW_MODE) xdp.command = XDP_SETUP_PROG_HW; else xdp.command = XDP_SETUP_PROG; xdp.flags = flags; xdp.prog = prog; err = bpf_op(dev, &xdp); if (!err && non_hw) bpf_prog_change_xdp(prev_prog, prog); if (prev_prog) bpf_prog_put(prev_prog); return err; } static void dev_xdp_uninstall(struct net_device *dev) { struct netdev_bpf xdp; bpf_op_t ndo_bpf; /* Remove generic XDP */ WARN_ON(dev_xdp_install(dev, generic_xdp_install, 0, NULL)); /* Remove from the driver */ ndo_bpf = dev->netdev_ops->ndo_bpf; if (!ndo_bpf) return; memset(&xdp, 0, sizeof(xdp)); xdp.command = XDP_QUERY_PROG; WARN_ON(ndo_bpf(dev, &xdp)); if (xdp.prog_id) WARN_ON(dev_xdp_install(dev, ndo_bpf, xdp.prog_flags, NULL)); /* Remove HW offload */ memset(&xdp, 0, sizeof(xdp)); xdp.command = XDP_QUERY_PROG_HW; if (!ndo_bpf(dev, &xdp) && xdp.prog_id) WARN_ON(dev_xdp_install(dev, ndo_bpf, xdp.prog_flags, NULL)); } /** * dev_change_xdp_fd - set or clear a bpf program for a device rx path * @dev: device * @fd: new program fd or negative value to clear * @flags: xdp-related flags * * Set or clear a bpf program for a device */ int dev_change_xdp_fd(struct net_device *dev, int fd, u32 flags) { const struct net_device_ops *ops = dev->netdev_ops; enum bpf_netdev_command query; struct bpf_prog *prog = NULL; bpf_op_t bpf_op, bpf_chk; int err; ASSERT_RTNL(); query = flags & XDP_FLAGS_HW_MODE ? XDP_QUERY_PROG_HW : XDP_QUERY_PROG; bpf_op = bpf_chk = ops->ndo_bpf; if (!bpf_op && (flags & (XDP_FLAGS_DRV_MODE | XDP_FLAGS_HW_MODE))) return -EOPNOTSUPP; if (!bpf_op || (flags & XDP_FLAGS_SKB_MODE)) bpf_op = generic_xdp_install; if (bpf_op == bpf_chk) bpf_chk = generic_xdp_install; if (fd >= 0) { if (__dev_xdp_query(dev, bpf_chk, XDP_QUERY_PROG) || __dev_xdp_query(dev, bpf_chk, XDP_QUERY_PROG_HW)) return -EEXIST; if ((flags & XDP_FLAGS_UPDATE_IF_NOEXIST) && __dev_xdp_query(dev, bpf_op, query)) return -EBUSY; prog = bpf_prog_get_type_dev(fd, BPF_PROG_TYPE_XDP, bpf_op == ops->ndo_bpf); if (IS_ERR(prog)) return PTR_ERR(prog); } err = dev_xdp_install(dev, bpf_op, flags, prog); if (err < 0 && prog) bpf_prog_put(prog); return err; } EXPORT_SYMBOL(dev_change_xdp_fd); /** * dev_new_index - allocate an ifindex * @net: the applicable net namespace * * Returns a suitable unique value for a new device interface * number. The caller must hold the rtnl semaphore or the * dev_base_lock to be sure it remains unique. */ static int dev_new_index(struct net *net) { int ifindex = net->ifindex; for (;;) { if (++ifindex <= 0) ifindex = 1; if (!__dev_get_by_index(net, ifindex)) return net->ifindex = ifindex; } } /* Delayed registration/unregisteration */ static LIST_HEAD(net_todo_list); DECLARE_WAIT_QUEUE_HEAD(netdev_unregistering_wq); static void net_set_todo(struct net_device *dev) { list_add_tail(&dev->todo_list, &net_todo_list); dev_net(dev)->dev_unreg_count++; } static void rollback_registered_many(struct list_head *head) { struct net_device *dev, *tmp; LIST_HEAD(close_head); BUG_ON(dev_boot_phase); ASSERT_RTNL(); list_for_each_entry_safe(dev, tmp, head, unreg_list) { /* Some devices call without registering * for initialization unwind. Remove those * devices and proceed with the remaining. */ if (dev->reg_state == NETREG_UNINITIALIZED) { pr_debug("unregister_netdevice: device %s/%p never was registered\n", dev->name, dev); WARN_ON(1); list_del(&dev->unreg_list); continue; } dev->dismantle = true; BUG_ON(dev->reg_state != NETREG_REGISTERED); } /* If device is running, close it first. */ list_for_each_entry(dev, head, unreg_list) list_add_tail(&dev->close_list, &close_head); dev_close_many(&close_head, true); list_for_each_entry(dev, head, unreg_list) { /* And unlink it from device chain. */ unlist_netdevice(dev); dev->reg_state = NETREG_UNREGISTERING; } flush_all_backlogs(); synchronize_net(); list_for_each_entry(dev, head, unreg_list) { struct sk_buff *skb = NULL; /* Shutdown queueing discipline. */ dev_shutdown(dev); dev_xdp_uninstall(dev); /* Notify protocols, that we are about to destroy * this device. They should clean all the things. */ call_netdevice_notifiers(NETDEV_UNREGISTER, dev); if (!dev->rtnl_link_ops || dev->rtnl_link_state == RTNL_LINK_INITIALIZED) skb = rtmsg_ifinfo_build_skb(RTM_DELLINK, dev, ~0U, GFP_KERNEL); /* * Flush the unicast and multicast chains */ dev_uc_flush(dev); dev_mc_flush(dev); if (dev->netdev_ops->ndo_uninit) dev->netdev_ops->ndo_uninit(dev); if (skb) rtmsg_ifinfo_send(skb, dev, GFP_KERNEL); /* Notifier chain MUST detach us all upper devices. */ WARN_ON(netdev_has_any_upper_dev(dev)); /* Remove entries from kobject tree */ netdev_unregister_kobject(dev); #ifdef CONFIG_XPS /* Remove XPS queueing entries */ netif_reset_xps_queues_gt(dev, 0); #endif } synchronize_net(); list_for_each_entry(dev, head, unreg_list) dev_put(dev); } static void rollback_registered(struct net_device *dev) { LIST_HEAD(single); list_add(&dev->unreg_list, &single); rollback_registered_many(&single); list_del(&single); } static netdev_features_t netdev_sync_upper_features(struct net_device *lower, struct net_device *upper, netdev_features_t features) { netdev_features_t upper_disables = NETIF_F_UPPER_DISABLES; netdev_features_t feature; int feature_bit; for_each_netdev_feature(upper_disables, feature_bit) { feature = __NETIF_F_BIT(feature_bit); if (!(upper->wanted_features & feature) && (features & feature)) { netdev_dbg(lower, "Dropping feature %pNF, upper dev %s has it off.\n", &feature, upper->name); features &= ~feature; } } return features; } static void netdev_sync_lower_features(struct net_device *upper, struct net_device *lower, netdev_features_t features) { netdev_features_t upper_disables = NETIF_F_UPPER_DISABLES; netdev_features_t feature; int feature_bit; for_each_netdev_feature(upper_disables, feature_bit) { feature = __NETIF_F_BIT(feature_bit); if (!(features & feature) && (lower->features & feature)) { netdev_dbg(upper, "Disabling feature %pNF on lower dev %s.\n", &feature, lower->name); lower->wanted_features &= ~feature; __netdev_update_features(lower); if (unlikely(lower->features & feature)) netdev_WARN(upper, "failed to disable %pNF on %s!\n", &feature, lower->name); else netdev_features_change(lower); } } } static netdev_features_t netdev_fix_features(struct net_device *dev, netdev_features_t features) { /* Fix illegal checksum combinations */ if ((features & NETIF_F_HW_CSUM) && (features & (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))) { netdev_warn(dev, "mixed HW and IP checksum settings.\n"); features &= ~(NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM); } /* TSO requires that SG is present as well. */ if ((features & NETIF_F_ALL_TSO) && !(features & NETIF_F_SG)) { netdev_dbg(dev, "Dropping TSO features since no SG feature.\n"); features &= ~NETIF_F_ALL_TSO; } if ((features & NETIF_F_TSO) && !(features & NETIF_F_HW_CSUM) && !(features & NETIF_F_IP_CSUM)) { netdev_dbg(dev, "Dropping TSO features since no CSUM feature.\n"); features &= ~NETIF_F_TSO; features &= ~NETIF_F_TSO_ECN; } if ((features & NETIF_F_TSO6) && !(features & NETIF_F_HW_CSUM) && !(features & NETIF_F_IPV6_CSUM)) { netdev_dbg(dev, "Dropping TSO6 features since no CSUM feature.\n"); features &= ~NETIF_F_TSO6; } /* TSO with IPv4 ID mangling requires IPv4 TSO be enabled */ if ((features & NETIF_F_TSO_MANGLEID) && !(features & NETIF_F_TSO)) features &= ~NETIF_F_TSO_MANGLEID; /* TSO ECN requires that TSO is present as well. */ if ((features & NETIF_F_ALL_TSO) == NETIF_F_TSO_ECN) features &= ~NETIF_F_TSO_ECN; /* Software GSO depends on SG. */ if ((features & NETIF_F_GSO) && !(features & NETIF_F_SG)) { netdev_dbg(dev, "Dropping NETIF_F_GSO since no SG feature.\n"); features &= ~NETIF_F_GSO; } /* UFO needs SG and checksumming */ if (features & NETIF_F_UFO) { /* maybe split UFO into V4 and V6? */ if (!(features & NETIF_F_HW_CSUM) && ((features & (NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM)) != (NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM))) { netdev_dbg(dev, "Dropping NETIF_F_UFO since no checksum offload features.\n"); features &= ~NETIF_F_UFO; } if (!(features & NETIF_F_SG)) { netdev_dbg(dev, "Dropping NETIF_F_UFO since no NETIF_F_SG feature.\n"); features &= ~NETIF_F_UFO; } } /* GSO partial features require GSO partial be set */ if ((features & dev->gso_partial_features) && !(features & NETIF_F_GSO_PARTIAL)) { netdev_dbg(dev, "Dropping partially supported GSO features since no GSO partial.\n"); features &= ~dev->gso_partial_features; } #ifdef CONFIG_NET_RX_BUSY_POLL if (dev->netdev_ops->ndo_busy_poll) features |= NETIF_F_BUSY_POLL; else #endif features &= ~NETIF_F_BUSY_POLL; return features; } int __netdev_update_features(struct net_device *dev) { struct net_device *upper, *lower; netdev_features_t features; struct list_head *iter; int err = -1; ASSERT_RTNL(); features = netdev_get_wanted_features(dev); if (dev->netdev_ops->ndo_fix_features) features = dev->netdev_ops->ndo_fix_features(dev, features); /* driver might be less strict about feature dependencies */ features = netdev_fix_features(dev, features); /* some features can't be enabled if they're off an an upper device */ netdev_for_each_upper_dev_rcu(dev, upper, iter) features = netdev_sync_upper_features(dev, upper, features); if (dev->features == features) goto sync_lower; netdev_dbg(dev, "Features changed: %pNF -> %pNF\n", &dev->features, &features); if (dev->netdev_ops->ndo_set_features) err = dev->netdev_ops->ndo_set_features(dev, features); else err = 0; if (unlikely(err < 0)) { netdev_err(dev, "set_features() failed (%d); wanted %pNF, left %pNF\n", err, &features, &dev->features); /* return non-0 since some features might have changed and * it's better to fire a spurious notification than miss it */ return -1; } sync_lower: /* some features must be disabled on lower devices when disabled * on an upper device (think: bonding master or bridge) */ netdev_for_each_lower_dev(dev, lower, iter) netdev_sync_lower_features(dev, lower, features); if (!err) dev->features = features; return err < 0 ? 0 : 1; } /** * netdev_update_features - recalculate device features * @dev: the device to check * * Recalculate dev->features set and send notifications if it * has changed. Should be called after driver or hardware dependent * conditions might have changed that influence the features. */ void netdev_update_features(struct net_device *dev) { if (__netdev_update_features(dev)) netdev_features_change(dev); } EXPORT_SYMBOL(netdev_update_features); /** * netdev_change_features - recalculate device features * @dev: the device to check * * Recalculate dev->features set and send notifications even * if they have not changed. Should be called instead of * netdev_update_features() if also dev->vlan_features might * have changed to allow the changes to be propagated to stacked * VLAN devices. */ void netdev_change_features(struct net_device *dev) { __netdev_update_features(dev); netdev_features_change(dev); } EXPORT_SYMBOL(netdev_change_features); /** * netif_stacked_transfer_operstate - transfer operstate * @rootdev: the root or lower level device to transfer state from * @dev: the device to transfer operstate to * * Transfer operational state from root to device. This is normally * called when a stacking relationship exists between the root * device and the device(a leaf device). */ void netif_stacked_transfer_operstate(const struct net_device *rootdev, struct net_device *dev) { if (rootdev->operstate == IF_OPER_DORMANT) netif_dormant_on(dev); else netif_dormant_off(dev); if (netif_carrier_ok(rootdev)) { if (!netif_carrier_ok(dev)) netif_carrier_on(dev); } else { if (netif_carrier_ok(dev)) netif_carrier_off(dev); } } EXPORT_SYMBOL(netif_stacked_transfer_operstate); static int netif_alloc_rx_queues(struct net_device *dev) { unsigned int i, count = dev->num_rx_queues; struct netdev_rx_queue *rx; size_t sz = count * sizeof(*rx); int err = 0; BUG_ON(count < 1); rx = kzalloc(sz, GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT); if (!rx) { rx = vzalloc(sz); if (!rx) return -ENOMEM; } dev->_rx = rx; for (i = 0; i < count; i++) { rx[i].dev = dev; /* XDP RX-queue setup */ err = xdp_rxq_info_reg(&rx[i].xdp_rxq, dev, i); if (err < 0) goto err_rxq_info; } return 0; err_rxq_info: /* Rollback successful reg's and free other resources */ while (i--) xdp_rxq_info_unreg(&rx[i].xdp_rxq); kfree(dev->_rx); dev->_rx = NULL; return err; } static void netif_free_rx_queues(struct net_device *dev) { unsigned int i, count = dev->num_rx_queues; struct netdev_rx_queue *rx; /* netif_alloc_rx_queues alloc failed, resources have been unreg'ed */ if (!dev->_rx) return; rx = dev->_rx; for (i = 0; i < count; i++) xdp_rxq_info_unreg(&rx[i].xdp_rxq); } static void netdev_init_one_queue(struct net_device *dev, struct netdev_queue *queue, void *_unused) { /* Initialize queue lock */ spin_lock_init(&queue->_xmit_lock); netdev_set_xmit_lockdep_class(&queue->_xmit_lock, dev->type); queue->xmit_lock_owner = -1; netdev_queue_numa_node_write(queue, NUMA_NO_NODE); queue->dev = dev; #ifdef CONFIG_BQL dql_init(&queue->dql, HZ); #endif } static void netif_free_tx_queues(struct net_device *dev) { kvfree(dev->_tx); } static int netif_alloc_netdev_queues(struct net_device *dev) { unsigned int count = dev->num_tx_queues; struct netdev_queue *tx; size_t sz = count * sizeof(*tx); if (count < 1 || count > 0xffff) return -EINVAL; tx = kzalloc(sz, GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT); if (!tx) { tx = vzalloc(sz); if (!tx) return -ENOMEM; } dev->_tx = tx; netdev_for_each_tx_queue(dev, netdev_init_one_queue, NULL); spin_lock_init(&dev->tx_global_lock); return 0; } void netif_tx_stop_all_queues(struct net_device *dev) { unsigned int i; for (i = 0; i < dev->num_tx_queues; i++) { struct netdev_queue *txq = netdev_get_tx_queue(dev, i); netif_tx_stop_queue(txq); } } EXPORT_SYMBOL(netif_tx_stop_all_queues); /** * register_netdevice - register a network device * @dev: device to register * * Take a completed network device structure and add it to the kernel * interfaces. A %NETDEV_REGISTER message is sent to the netdev notifier * chain. 0 is returned on success. A negative errno code is returned * on a failure to set up the device, or if the name is a duplicate. * * Callers must hold the rtnl semaphore. You may want * register_netdev() instead of this. * * BUGS: * The locking appears insufficient to guarantee two parallel registers * will not get the same name. */ int register_netdevice(struct net_device *dev) { int ret; struct net *net = dev_net(dev); BUG_ON(dev_boot_phase); ASSERT_RTNL(); might_sleep(); /* When net_device's are persistent, this will be fatal. */ BUG_ON(dev->reg_state != NETREG_UNINITIALIZED); BUG_ON(!net); spin_lock_init(&dev->addr_list_lock); netdev_set_addr_lockdep_class(dev); ret = dev_get_valid_name(net, dev, dev->name); if (ret < 0) goto out; /* Init, if this function is available */ if (dev->netdev_ops->ndo_init) { ret = dev->netdev_ops->ndo_init(dev); if (ret) { if (ret > 0) ret = -EIO; goto out; } } if (((dev->hw_features | dev->features) & NETIF_F_HW_VLAN_CTAG_FILTER) && (!dev->netdev_ops->ndo_vlan_rx_add_vid || !dev->netdev_ops->ndo_vlan_rx_kill_vid)) { netdev_WARN(dev, "Buggy VLAN acceleration in driver!\n"); ret = -EINVAL; goto err_uninit; } ret = -EBUSY; if (!dev->ifindex) dev->ifindex = dev_new_index(net); else if (__dev_get_by_index(net, dev->ifindex)) goto err_uninit; /* Transfer changeable features to wanted_features and enable * software offloads (GSO and GRO). */ dev->hw_features |= NETIF_F_SOFT_FEATURES; dev->features |= NETIF_F_SOFT_FEATURES; dev->wanted_features = dev->features & dev->hw_features; if (!(dev->flags & IFF_LOOPBACK)) dev->hw_features |= NETIF_F_NOCACHE_COPY; /* If IPv4 TCP segmentation offload is supported we should also * allow the device to enable segmenting the frame with the option * of ignoring a static IP ID value. This doesn't enable the * feature itself but allows the user to enable it later. */ if (dev->hw_features & NETIF_F_TSO) dev->hw_features |= NETIF_F_TSO_MANGLEID; if (dev->vlan_features & NETIF_F_TSO) dev->vlan_features |= NETIF_F_TSO_MANGLEID; if (dev->mpls_features & NETIF_F_TSO) dev->mpls_features |= NETIF_F_TSO_MANGLEID; if (dev->hw_enc_features & NETIF_F_TSO) dev->hw_enc_features |= NETIF_F_TSO_MANGLEID; /* Make NETIF_F_HIGHDMA inheritable to VLAN devices. */ dev->vlan_features |= NETIF_F_HIGHDMA; /* Make NETIF_F_SG inheritable to tunnel devices. */ dev->hw_enc_features |= NETIF_F_SG | NETIF_F_GSO_PARTIAL; /* Make NETIF_F_SG inheritable to MPLS. */ dev->mpls_features |= NETIF_F_SG; ret = call_netdevice_notifiers(NETDEV_POST_INIT, dev); ret = notifier_to_errno(ret); if (ret) goto err_uninit; ret = netdev_register_kobject(dev); if (ret) goto err_uninit; dev->reg_state = NETREG_REGISTERED; __netdev_update_features(dev); /* * Default initial state at registry is that the * device is present. */ set_bit(__LINK_STATE_PRESENT, &dev->state); linkwatch_init_dev(dev); dev_init_scheduler(dev); dev_hold(dev); list_netdevice(dev); add_device_randomness(dev->dev_addr, dev->addr_len); /* If the device has permanent device address, driver should * set dev_addr and also addr_assign_type should be set to * NET_ADDR_PERM (default value). */ if (dev->addr_assign_type == NET_ADDR_PERM) memcpy(dev->perm_addr, dev->dev_addr, dev->addr_len); /* Notify protocols, that a new device appeared. */ ret = call_netdevice_notifiers(NETDEV_REGISTER, dev); ret = notifier_to_errno(ret); if (ret) { rollback_registered(dev); rcu_barrier(); dev->reg_state = NETREG_UNREGISTERED; /* We should put the kobject that hold in * netdev_unregister_kobject(), otherwise * the net device cannot be freed when * driver calls free_netdev(), because the * kobject is being hold. */ kobject_put(&dev->dev.kobj); } /* * Prevent userspace races by waiting until the network * device is fully setup before sending notifications. */ if (!dev->rtnl_link_ops || dev->rtnl_link_state == RTNL_LINK_INITIALIZED) rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U, GFP_KERNEL); out: return ret; err_uninit: if (dev->netdev_ops->ndo_uninit) dev->netdev_ops->ndo_uninit(dev); goto out; } EXPORT_SYMBOL(register_netdevice); /** * init_dummy_netdev - init a dummy network device for NAPI * @dev: device to init * * This takes a network device structure and initialize the minimum * amount of fields so it can be used to schedule NAPI polls without * registering a full blown interface. This is to be used by drivers * that need to tie several hardware interfaces to a single NAPI * poll scheduler due to HW limitations. */ int init_dummy_netdev(struct net_device *dev) { /* Clear everything. Note we don't initialize spinlocks * are they aren't supposed to be taken by any of the * NAPI code and this dummy netdev is supposed to be * only ever used for NAPI polls */ memset(dev, 0, sizeof(struct net_device)); /* make sure we BUG if trying to hit standard * register/unregister code path */ dev->reg_state = NETREG_DUMMY; /* NAPI wants this */ INIT_LIST_HEAD(&dev->napi_list); /* a dummy interface is started by default */ set_bit(__LINK_STATE_PRESENT, &dev->state); set_bit(__LINK_STATE_START, &dev->state); /* Note : We dont allocate pcpu_refcnt for dummy devices, * because users of this 'device' dont need to change * its refcount. */ return 0; } EXPORT_SYMBOL_GPL(init_dummy_netdev); /** * register_netdev - register a network device * @dev: device to register * * Take a completed network device structure and add it to the kernel * interfaces. A %NETDEV_REGISTER message is sent to the netdev notifier * chain. 0 is returned on success. A negative errno code is returned * on a failure to set up the device, or if the name is a duplicate. * * This is a wrapper around register_netdevice that takes the rtnl semaphore * and expands the device name if you passed a format string to * alloc_netdev. */ int register_netdev(struct net_device *dev) { int err; rtnl_lock(); err = register_netdevice(dev); rtnl_unlock(); return err; } EXPORT_SYMBOL(register_netdev); int netdev_refcnt_read(const struct net_device *dev) { int i, refcnt = 0; for_each_possible_cpu(i) refcnt += *per_cpu_ptr(dev->pcpu_refcnt, i); return refcnt; } EXPORT_SYMBOL(netdev_refcnt_read); /** * netdev_wait_allrefs - wait until all references are gone. * @dev: target net_device * * This is called when unregistering network devices. * * Any protocol or device that holds a reference should register * for netdevice notification, and cleanup and put back the * reference if they receive an UNREGISTER event. * We can get stuck here if buggy protocols don't correctly * call dev_put. */ static void netdev_wait_allrefs(struct net_device *dev) { unsigned long rebroadcast_time, warning_time; int refcnt; linkwatch_forget_dev(dev); rebroadcast_time = warning_time = jiffies; refcnt = netdev_refcnt_read(dev); while (refcnt != 0) { if (time_after(jiffies, rebroadcast_time + 1 * HZ)) { rtnl_lock(); /* Rebroadcast unregister notification */ call_netdevice_notifiers(NETDEV_UNREGISTER, dev); __rtnl_unlock(); rcu_barrier(); rtnl_lock(); call_netdevice_notifiers(NETDEV_UNREGISTER_FINAL, dev); if (test_bit(__LINK_STATE_LINKWATCH_PENDING, &dev->state)) { /* We must not have linkwatch events * pending on unregister. If this * happens, we simply run the queue * unscheduled, resulting in a noop * for this device. */ linkwatch_run_queue(); } __rtnl_unlock(); rebroadcast_time = jiffies; } msleep(250); refcnt = netdev_refcnt_read(dev); if (refcnt && time_after(jiffies, warning_time + 10 * HZ)) { pr_emerg("unregister_netdevice: waiting for %s to become free. Usage count = %d\n", dev->name, refcnt); warning_time = jiffies; } } } /* The sequence is: * * rtnl_lock(); * ... * register_netdevice(x1); * register_netdevice(x2); * ... * unregister_netdevice(y1); * unregister_netdevice(y2); * ... * rtnl_unlock(); * free_netdev(y1); * free_netdev(y2); * * We are invoked by rtnl_unlock(). * This allows us to deal with problems: * 1) We can delete sysfs objects which invoke hotplug * without deadlocking with linkwatch via keventd. * 2) Since we run with the RTNL semaphore not held, we can sleep * safely in order to wait for the netdev refcnt to drop to zero. * * We must not return until all unregister events added during * the interval the lock was held have been completed. */ void netdev_run_todo(void) { struct list_head list; /* Snapshot list, allow later requests */ list_replace_init(&net_todo_list, &list); __rtnl_unlock(); /* Wait for rcu callbacks to finish before next phase */ if (!list_empty(&list)) rcu_barrier(); while (!list_empty(&list)) { struct net_device *dev = list_first_entry(&list, struct net_device, todo_list); list_del(&dev->todo_list); rtnl_lock(); call_netdevice_notifiers(NETDEV_UNREGISTER_FINAL, dev); __rtnl_unlock(); if (unlikely(dev->reg_state != NETREG_UNREGISTERING)) { pr_err("network todo '%s' but state %d\n", dev->name, dev->reg_state); dump_stack(); continue; } dev->reg_state = NETREG_UNREGISTERED; netdev_wait_allrefs(dev); /* paranoia */ BUG_ON(netdev_refcnt_read(dev)); BUG_ON(!list_empty(&dev->ptype_all)); BUG_ON(!list_empty(&dev->ptype_specific)); WARN_ON(rcu_access_pointer(dev->ip_ptr)); WARN_ON(rcu_access_pointer(dev->ip6_ptr)); WARN_ON(dev->dn_ptr); if (dev->destructor) dev->destructor(dev); /* Report a network device has been unregistered */ rtnl_lock(); dev_net(dev)->dev_unreg_count--; __rtnl_unlock(); wake_up(&netdev_unregistering_wq); /* Free network device */ kobject_put(&dev->dev.kobj); } } /* Convert net_device_stats to rtnl_link_stats64. rtnl_link_stats64 has * all the same fields in the same order as net_device_stats, with only * the type differing, but rtnl_link_stats64 may have additional fields * at the end for newer counters. */ void netdev_stats_to_stats64(struct rtnl_link_stats64 *stats64, const struct net_device_stats *netdev_stats) { #if BITS_PER_LONG == 64 BUILD_BUG_ON(sizeof(*stats64) < sizeof(*netdev_stats)); memcpy(stats64, netdev_stats, sizeof(*netdev_stats)); /* zero out counters that only exist in rtnl_link_stats64 */ memset((char *)stats64 + sizeof(*netdev_stats), 0, sizeof(*stats64) - sizeof(*netdev_stats)); #else size_t i, n = sizeof(*netdev_stats) / sizeof(unsigned long); const unsigned long *src = (const unsigned long *)netdev_stats; u64 *dst = (u64 *)stats64; BUILD_BUG_ON(n > sizeof(*stats64) / sizeof(u64)); for (i = 0; i < n; i++) dst[i] = src[i]; /* zero out counters that only exist in rtnl_link_stats64 */ memset((char *)stats64 + n * sizeof(u64), 0, sizeof(*stats64) - n * sizeof(u64)); #endif } EXPORT_SYMBOL(netdev_stats_to_stats64); /** * dev_get_stats - get network device statistics * @dev: device to get statistics from * @storage: place to store stats * * Get network statistics from device. Return @storage. * The device driver may provide its own method by setting * dev->netdev_ops->get_stats64 or dev->netdev_ops->get_stats; * otherwise the internal statistics structure is used. */ struct rtnl_link_stats64 *dev_get_stats(struct net_device *dev, struct rtnl_link_stats64 *storage) { const struct net_device_ops *ops = dev->netdev_ops; if (ops->ndo_get_stats64) { memset(storage, 0, sizeof(*storage)); ops->ndo_get_stats64(dev, storage); } else if (ops->ndo_get_stats) { netdev_stats_to_stats64(storage, ops->ndo_get_stats(dev)); } else { netdev_stats_to_stats64(storage, &dev->stats); } storage->rx_dropped += (unsigned long)atomic_long_read(&dev->rx_dropped); storage->tx_dropped += (unsigned long)atomic_long_read(&dev->tx_dropped); storage->rx_nohandler += (unsigned long)atomic_long_read(&dev->rx_nohandler); return storage; } EXPORT_SYMBOL(dev_get_stats); struct netdev_queue *dev_ingress_queue_create(struct net_device *dev) { struct netdev_queue *queue = dev_ingress_queue(dev); #ifdef CONFIG_NET_CLS_ACT if (queue) return queue; queue = kzalloc(sizeof(*queue), GFP_KERNEL); if (!queue) return NULL; netdev_init_one_queue(dev, queue, NULL); RCU_INIT_POINTER(queue->qdisc, &noop_qdisc); queue->qdisc_sleeping = &noop_qdisc; rcu_assign_pointer(dev->ingress_queue, queue); #endif return queue; } static const struct ethtool_ops default_ethtool_ops; void netdev_set_default_ethtool_ops(struct net_device *dev, const struct ethtool_ops *ops) { if (dev->ethtool_ops == &default_ethtool_ops) dev->ethtool_ops = ops; } EXPORT_SYMBOL_GPL(netdev_set_default_ethtool_ops); void netdev_freemem(struct net_device *dev) { char *addr = (char *)dev - dev->padded; kvfree(addr); } /** * alloc_netdev_mqs - allocate network device * @sizeof_priv: size of private data to allocate space for * @name: device name format string * @name_assign_type: origin of device name * @setup: callback to initialize device * @txqs: the number of TX subqueues to allocate * @rxqs: the number of RX subqueues to allocate * * Allocates a struct net_device with private data area for driver use * and performs basic initialization. Also allocates subqueue structs * for each queue on the device. */ struct net_device *alloc_netdev_mqs(int sizeof_priv, const char *name, unsigned char name_assign_type, void (*setup)(struct net_device *), unsigned int txqs, unsigned int rxqs) { struct net_device *dev; size_t alloc_size; struct net_device *p; BUG_ON(strlen(name) >= sizeof(dev->name)); if (txqs < 1) { pr_err("alloc_netdev: Unable to allocate device with zero queues\n"); return NULL; } if (rxqs < 1) { pr_err("alloc_netdev: Unable to allocate device with zero RX queues\n"); return NULL; } alloc_size = sizeof(struct net_device); if (sizeof_priv) { /* ensure 32-byte alignment of private area */ alloc_size = ALIGN(alloc_size, NETDEV_ALIGN); alloc_size += sizeof_priv; } /* ensure 32-byte alignment of whole construct */ alloc_size += NETDEV_ALIGN - 1; p = kzalloc(alloc_size, GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT); if (!p) p = vzalloc(alloc_size); if (!p) return NULL; dev = PTR_ALIGN(p, NETDEV_ALIGN); dev->padded = (char *)dev - (char *)p; dev->pcpu_refcnt = alloc_percpu(int); if (!dev->pcpu_refcnt) goto free_dev; if (dev_addr_init(dev)) goto free_pcpu; dev_mc_init(dev); dev_uc_init(dev); dev_net_set(dev, &init_net); dev->gso_max_size = GSO_MAX_SIZE; dev->gso_max_segs = GSO_MAX_SEGS; INIT_LIST_HEAD(&dev->napi_list); INIT_LIST_HEAD(&dev->unreg_list); INIT_LIST_HEAD(&dev->close_list); INIT_LIST_HEAD(&dev->link_watch_list); INIT_LIST_HEAD(&dev->adj_list.upper); INIT_LIST_HEAD(&dev->adj_list.lower); INIT_LIST_HEAD(&dev->all_adj_list.upper); INIT_LIST_HEAD(&dev->all_adj_list.lower); INIT_LIST_HEAD(&dev->ptype_all); INIT_LIST_HEAD(&dev->ptype_specific); #ifdef CONFIG_NET_SCHED hash_init(dev->qdisc_hash); #endif dev->priv_flags = IFF_XMIT_DST_RELEASE | IFF_XMIT_DST_RELEASE_PERM; setup(dev); if (!dev->tx_queue_len) { dev->priv_flags |= IFF_NO_QUEUE; dev->tx_queue_len = 1; } dev->num_tx_queues = txqs; dev->real_num_tx_queues = txqs; if (netif_alloc_netdev_queues(dev)) goto free_all; dev->num_rx_queues = rxqs; dev->real_num_rx_queues = rxqs; if (netif_alloc_rx_queues(dev)) goto free_all; strcpy(dev->name, name); dev->name_assign_type = name_assign_type; dev->group = INIT_NETDEV_GROUP; if (!dev->ethtool_ops) dev->ethtool_ops = &default_ethtool_ops; nf_hook_ingress_init(dev); return dev; free_all: free_netdev(dev); return NULL; free_pcpu: free_percpu(dev->pcpu_refcnt); free_dev: netdev_freemem(dev); return NULL; } EXPORT_SYMBOL(alloc_netdev_mqs); /** * free_netdev - free network device * @dev: device * * This function does the last stage of destroying an allocated device * interface. The reference to the device object is released. If this * is the last reference then it will be freed.Must be called in process * context. */ void free_netdev(struct net_device *dev) { struct napi_struct *p, *n; might_sleep(); netif_free_tx_queues(dev); netif_free_rx_queues(dev); kfree(rcu_dereference_protected(dev->ingress_queue, 1)); /* Flush device addresses */ dev_addr_flush(dev); list_for_each_entry_safe(p, n, &dev->napi_list, dev_list) netif_napi_del(p); free_percpu(dev->pcpu_refcnt); dev->pcpu_refcnt = NULL; /* Compatibility with error handling in drivers */ if (dev->reg_state == NETREG_UNINITIALIZED) { netdev_freemem(dev); return; } BUG_ON(dev->reg_state != NETREG_UNREGISTERED); dev->reg_state = NETREG_RELEASED; /* will free via device release */ put_device(&dev->dev); } EXPORT_SYMBOL(free_netdev); /** * synchronize_net - Synchronize with packet receive processing * * Wait for packets currently being received to be done. * Does not block later packets from starting. */ void synchronize_net(void) { might_sleep(); if (rtnl_is_locked()) synchronize_rcu_expedited(); else synchronize_rcu(); } EXPORT_SYMBOL(synchronize_net); /** * unregister_netdevice_queue - remove device from the kernel * @dev: device * @head: list * * This function shuts down a device interface and removes it * from the kernel tables. * If head not NULL, device is queued to be unregistered later. * * Callers must hold the rtnl semaphore. You may want * unregister_netdev() instead of this. */ void unregister_netdevice_queue(struct net_device *dev, struct list_head *head) { ASSERT_RTNL(); if (head) { list_move_tail(&dev->unreg_list, head); } else { rollback_registered(dev); /* Finish processing unregister after unlock */ net_set_todo(dev); } } EXPORT_SYMBOL(unregister_netdevice_queue); /** * unregister_netdevice_many - unregister many devices * @head: list of devices * * Note: As most callers use a stack allocated list_head, * we force a list_del() to make sure stack wont be corrupted later. */ void unregister_netdevice_many(struct list_head *head) { struct net_device *dev; if (!list_empty(head)) { rollback_registered_many(head); list_for_each_entry(dev, head, unreg_list) net_set_todo(dev); list_del(head); } } EXPORT_SYMBOL(unregister_netdevice_many); /** * unregister_netdev - remove device from the kernel * @dev: device * * This function shuts down a device interface and removes it * from the kernel tables. * * This is just a wrapper for unregister_netdevice that takes * the rtnl semaphore. In general you want to use this and not * unregister_netdevice. */ void unregister_netdev(struct net_device *dev) { rtnl_lock(); unregister_netdevice(dev); rtnl_unlock(); } EXPORT_SYMBOL(unregister_netdev); /** * dev_change_net_namespace - move device to different nethost namespace * @dev: device * @net: network namespace * @pat: If not NULL name pattern to try if the current device name * is already taken in the destination network namespace. * * This function shuts down a device interface and moves it * to a new network namespace. On success 0 is returned, on * a failure a netagive errno code is returned. * * Callers must hold the rtnl semaphore. */ int dev_change_net_namespace(struct net_device *dev, struct net *net, const char *pat) { int err; ASSERT_RTNL(); /* Don't allow namespace local devices to be moved. */ err = -EINVAL; if (dev->features & NETIF_F_NETNS_LOCAL) goto out; /* Ensure the device has been registrered */ if (dev->reg_state != NETREG_REGISTERED) goto out; /* Get out if there is nothing todo */ err = 0; if (net_eq(dev_net(dev), net)) goto out; /* Pick the destination device name, and ensure * we can use it in the destination network namespace. */ err = -EEXIST; if (__dev_get_by_name(net, dev->name)) { /* We get here if we can't use the current device name */ if (!pat) goto out; err = dev_get_valid_name(net, dev, pat); if (err < 0) goto out; } /* * And now a mini version of register_netdevice unregister_netdevice. */ /* If device is running close it first. */ dev_close(dev); /* And unlink it from device chain */ unlist_netdevice(dev); synchronize_net(); /* Shutdown queueing discipline. */ dev_shutdown(dev); /* Notify protocols, that we are about to destroy * this device. They should clean all the things. * * Note that dev->reg_state stays at NETREG_REGISTERED. * This is wanted because this way 8021q and macvlan know * the device is just moving and can keep their slaves up. */ call_netdevice_notifiers(NETDEV_UNREGISTER, dev); rcu_barrier(); call_netdevice_notifiers(NETDEV_UNREGISTER_FINAL, dev); rtmsg_ifinfo(RTM_DELLINK, dev, ~0U, GFP_KERNEL); /* * Flush the unicast and multicast chains */ dev_uc_flush(dev); dev_mc_flush(dev); /* Send a netdev-removed uevent to the old namespace */ kobject_uevent(&dev->dev.kobj, KOBJ_REMOVE); netdev_adjacent_del_links(dev); /* Actually switch the network namespace */ dev_net_set(dev, net); /* If there is an ifindex conflict assign a new one */ if (__dev_get_by_index(net, dev->ifindex)) dev->ifindex = dev_new_index(net); /* Send a netdev-add uevent to the new namespace */ kobject_uevent(&dev->dev.kobj, KOBJ_ADD); netdev_adjacent_add_links(dev); /* Fixup kobjects */ err = device_rename(&dev->dev, dev->name); WARN_ON(err); /* Add the device back in the hashes */ list_netdevice(dev); /* Notify protocols, that a new device appeared. */ call_netdevice_notifiers(NETDEV_REGISTER, dev); /* * Prevent userspace races by waiting until the network * device is fully setup before sending notifications. */ rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U, GFP_KERNEL); synchronize_net(); err = 0; out: return err; } EXPORT_SYMBOL_GPL(dev_change_net_namespace); static int dev_cpu_callback(struct notifier_block *nfb, unsigned long action, void *ocpu) { struct sk_buff **list_skb; struct sk_buff *skb; unsigned int cpu, oldcpu = (unsigned long)ocpu; struct softnet_data *sd, *oldsd, *remsd; if (action != CPU_DEAD && action != CPU_DEAD_FROZEN) return NOTIFY_OK; local_irq_disable(); cpu = smp_processor_id(); sd = &per_cpu(softnet_data, cpu); oldsd = &per_cpu(softnet_data, oldcpu); /* Find end of our completion_queue. */ list_skb = &sd->completion_queue; while (*list_skb) list_skb = &(*list_skb)->next; /* Append completion queue from offline CPU. */ *list_skb = oldsd->completion_queue; oldsd->completion_queue = NULL; /* Append output queue from offline CPU. */ if (oldsd->output_queue) { *sd->output_queue_tailp = oldsd->output_queue; sd->output_queue_tailp = oldsd->output_queue_tailp; oldsd->output_queue = NULL; oldsd->output_queue_tailp = &oldsd->output_queue; } /* Append NAPI poll list from offline CPU, with one exception : * process_backlog() must be called by cpu owning percpu backlog. * We properly handle process_queue & input_pkt_queue later. */ while (!list_empty(&oldsd->poll_list)) { struct napi_struct *napi = list_first_entry(&oldsd->poll_list, struct napi_struct, poll_list); list_del_init(&napi->poll_list); if (napi->poll == process_backlog) napi->state = 0; else ____napi_schedule(sd, napi); } raise_softirq_irqoff(NET_TX_SOFTIRQ); local_irq_enable(); #ifdef CONFIG_RPS remsd = oldsd->rps_ipi_list; oldsd->rps_ipi_list = NULL; #endif /* send out pending IPI's on offline CPU */ net_rps_send_ipi(remsd); /* Process offline CPU's input_pkt_queue */ while ((skb = __skb_dequeue(&oldsd->process_queue))) { netif_rx_ni(skb); input_queue_head_incr(oldsd); } while ((skb = skb_dequeue(&oldsd->input_pkt_queue))) { netif_rx_ni(skb); input_queue_head_incr(oldsd); } return NOTIFY_OK; } /** * netdev_increment_features - increment feature set by one * @all: current feature set * @one: new feature set * @mask: mask feature set * * Computes a new feature set after adding a device with feature set * @one to the master device with current feature set @all. Will not * enable anything that is off in @mask. Returns the new feature set. */ netdev_features_t netdev_increment_features(netdev_features_t all, netdev_features_t one, netdev_features_t mask) { if (mask & NETIF_F_HW_CSUM) mask |= NETIF_F_CSUM_MASK; mask |= NETIF_F_VLAN_CHALLENGED; all |= one & (NETIF_F_ONE_FOR_ALL | NETIF_F_CSUM_MASK) & mask; all &= one | ~NETIF_F_ALL_FOR_ALL; /* If one device supports hw checksumming, set for all. */ if (all & NETIF_F_HW_CSUM) all &= ~(NETIF_F_CSUM_MASK & ~NETIF_F_HW_CSUM); return all; } EXPORT_SYMBOL(netdev_increment_features); static struct hlist_head * __net_init netdev_create_hash(void) { int i; struct hlist_head *hash; hash = kmalloc(sizeof(*hash) * NETDEV_HASHENTRIES, GFP_KERNEL); if (hash != NULL) for (i = 0; i < NETDEV_HASHENTRIES; i++) INIT_HLIST_HEAD(&hash[i]); return hash; } /* Initialize per network namespace state */ static int __net_init netdev_init(struct net *net) { if (net != &init_net) INIT_LIST_HEAD(&net->dev_base_head); net->dev_name_head = netdev_create_hash(); if (net->dev_name_head == NULL) goto err_name; net->dev_index_head = netdev_create_hash(); if (net->dev_index_head == NULL) goto err_idx; return 0; err_idx: kfree(net->dev_name_head); err_name: return -ENOMEM; } /** * netdev_drivername - network driver for the device * @dev: network device * * Determine network driver for device. */ const char *netdev_drivername(const struct net_device *dev) { const struct device_driver *driver; const struct device *parent; const char *empty = ""; parent = dev->dev.parent; if (!parent) return empty; driver = parent->driver; if (driver && driver->name) return driver->name; return empty; } static void __netdev_printk(const char *level, const struct net_device *dev, struct va_format *vaf) { if (dev && dev->dev.parent) { dev_printk_emit(level[1] - '0', dev->dev.parent, "%s %s %s%s: %pV", dev_driver_string(dev->dev.parent), dev_name(dev->dev.parent), netdev_name(dev), netdev_reg_state(dev), vaf); } else if (dev) { printk("%s%s%s: %pV", level, netdev_name(dev), netdev_reg_state(dev), vaf); } else { printk("%s(NULL net_device): %pV", level, vaf); } } void netdev_printk(const char *level, const struct net_device *dev, const char *format, ...) { struct va_format vaf; va_list args; va_start(args, format); vaf.fmt = format; vaf.va = &args; __netdev_printk(level, dev, &vaf); va_end(args); } EXPORT_SYMBOL(netdev_printk); #define define_netdev_printk_level(func, level) \ void func(const struct net_device *dev, const char *fmt, ...) \ { \ struct va_format vaf; \ va_list args; \ \ va_start(args, fmt); \ \ vaf.fmt = fmt; \ vaf.va = &args; \ \ __netdev_printk(level, dev, &vaf); \ \ va_end(args); \ } \ EXPORT_SYMBOL(func); define_netdev_printk_level(netdev_emerg, KERN_EMERG); define_netdev_printk_level(netdev_alert, KERN_ALERT); define_netdev_printk_level(netdev_crit, KERN_CRIT); define_netdev_printk_level(netdev_err, KERN_ERR); define_netdev_printk_level(netdev_warn, KERN_WARNING); define_netdev_printk_level(netdev_notice, KERN_NOTICE); define_netdev_printk_level(netdev_info, KERN_INFO); static void __net_exit netdev_exit(struct net *net) { kfree(net->dev_name_head); kfree(net->dev_index_head); } static struct pernet_operations __net_initdata netdev_net_ops = { .init = netdev_init, .exit = netdev_exit, }; static void __net_exit default_device_exit(struct net *net) { struct net_device *dev, *aux; /* * Push all migratable network devices back to the * initial network namespace */ rtnl_lock(); for_each_netdev_safe(net, dev, aux) { int err; char fb_name[IFNAMSIZ]; /* Ignore unmoveable devices (i.e. loopback) */ if (dev->features & NETIF_F_NETNS_LOCAL) continue; /* Leave virtual devices for the generic cleanup */ if (dev->rtnl_link_ops && !dev->rtnl_link_ops->netns_refund) continue; /* Push remaining network devices to init_net */ snprintf(fb_name, IFNAMSIZ, "dev%d", dev->ifindex); if (__dev_get_by_name(&init_net, fb_name)) snprintf(fb_name, IFNAMSIZ, "dev%%d"); err = dev_change_net_namespace(dev, &init_net, fb_name); if (err) { pr_emerg("%s: failed to move %s to init_net: %d\n", __func__, dev->name, err); BUG(); } } rtnl_unlock(); } static void __net_exit rtnl_lock_unregistering(struct list_head *net_list) { /* Return with the rtnl_lock held when there are no network * devices unregistering in any network namespace in net_list. */ struct net *net; bool unregistering; DEFINE_WAIT_FUNC(wait, woken_wake_function); add_wait_queue(&netdev_unregistering_wq, &wait); for (;;) { unregistering = false; rtnl_lock(); list_for_each_entry(net, net_list, exit_list) { if (net->dev_unreg_count > 0) { unregistering = true; break; } } if (!unregistering) break; __rtnl_unlock(); wait_woken(&wait, TASK_UNINTERRUPTIBLE, MAX_SCHEDULE_TIMEOUT); } remove_wait_queue(&netdev_unregistering_wq, &wait); } static void __net_exit default_device_exit_batch(struct list_head *net_list) { /* At exit all network devices most be removed from a network * namespace. Do this in the reverse order of registration. * Do this across as many network namespaces as possible to * improve batching efficiency. */ struct net_device *dev; struct net *net; LIST_HEAD(dev_kill_list); /* To prevent network device cleanup code from dereferencing * loopback devices or network devices that have been freed * wait here for all pending unregistrations to complete, * before unregistring the loopback device and allowing the * network namespace be freed. * * The netdev todo list containing all network devices * unregistrations that happen in default_device_exit_batch * will run in the rtnl_unlock() at the end of * default_device_exit_batch. */ rtnl_lock_unregistering(net_list); list_for_each_entry(net, net_list, exit_list) { for_each_netdev_reverse(net, dev) { if (dev->rtnl_link_ops && dev->rtnl_link_ops->dellink) dev->rtnl_link_ops->dellink(dev, &dev_kill_list); else unregister_netdevice_queue(dev, &dev_kill_list); } } unregister_netdevice_many(&dev_kill_list); rtnl_unlock(); } static struct pernet_operations __net_initdata default_device_ops = { .exit = default_device_exit, .exit_batch = default_device_exit_batch, }; /* * Initialize the DEV module. At boot time this walks the device list and * unhooks any devices that fail to initialise (normally hardware not * present) and leaves us with a valid list of present and active devices. * */ /* * This is called single threaded during boot, so no need * to take the rtnl semaphore. */ static int __init net_dev_init(void) { int i, rc = -ENOMEM; BUG_ON(!dev_boot_phase); if (dev_proc_init()) goto out; if (netdev_kobject_init()) goto out; INIT_LIST_HEAD(&ptype_all); for (i = 0; i < PTYPE_HASH_SIZE; i++) INIT_LIST_HEAD(&ptype_base[i]); INIT_LIST_HEAD(&offload_base); if (register_pernet_subsys(&netdev_net_ops)) goto out; /* * Initialise the packet receive queues. */ for_each_possible_cpu(i) { struct work_struct *flush = per_cpu_ptr(&flush_works, i); struct softnet_data *sd = &per_cpu(softnet_data, i); INIT_WORK(flush, flush_backlog); skb_queue_head_init(&sd->input_pkt_queue); skb_queue_head_init(&sd->process_queue); INIT_LIST_HEAD(&sd->poll_list); sd->output_queue_tailp = &sd->output_queue; #ifdef CONFIG_RPS sd->csd.func = rps_trigger_softirq; sd->csd.info = sd; sd->cpu = i; #endif sd->backlog.poll = process_backlog; sd->backlog.weight = weight_p; } dev_boot_phase = 0; /* The loopback device is special if any other network devices * is present in a network namespace the loopback device must * be present. Since we now dynamically allocate and free the * loopback device ensure this invariant is maintained by * keeping the loopback device as the first device on the * list of network devices. Ensuring the loopback devices * is the first device that appears and the last network device * that disappears. */ if (register_pernet_device(&loopback_net_ops)) goto out; if (register_pernet_device(&default_device_ops)) goto out; open_softirq(NET_TX_SOFTIRQ, net_tx_action); open_softirq(NET_RX_SOFTIRQ, net_rx_action); hotcpu_notifier(dev_cpu_callback, 0); dst_subsys_init(); rc = 0; out: return rc; } subsys_initcall(net_dev_init);