/* * 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 "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) /* * The list of packet types we will receive (as opposed to discard) * and the routines to invoke. * * Why 16. Because with 16 the only overlap we get on a hash of the * low nibble of the protocol value is RARP/SNAP/X.25. * * NOTE: That is no longer true with the addition of VLAN tags. Not * sure which should go first, but I bet it won't make much * difference if we are running VLANs. The good news is that * this protocol won't be in the list unless compiled in, so * the average user (w/out VLANs) will not be adversely affected. * --BLG * * 0800 IP * 8100 802.1Q VLAN * 0001 802.3 * 0002 AX.25 * 0004 802.2 * 8035 RARP * 0005 SNAP * 0805 X.25 * 0806 ARP * 8137 IPX * 0009 Localtalk * 86DD IPv6 */ #define PTYPE_HASH_SIZE (16) #define PTYPE_HASH_MASK (PTYPE_HASH_SIZE - 1) static DEFINE_SPINLOCK(ptype_lock); static DEFINE_SPINLOCK(offload_lock); static struct list_head ptype_base[PTYPE_HASH_SIZE] __read_mostly; static struct list_head ptype_all __read_mostly; /* Taps */ static struct list_head offload_base __read_mostly; /* * 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); seqcount_t devnet_rename_seq; 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(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 int 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); return 0; } /* 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 &ptype_all; else return &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 list_head *head = &offload_base; spin_lock(&offload_lock); list_add_rcu(&po->list, head); 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. */ 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); } EXPORT_SYMBOL(__dev_remove_offload); /** * 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_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 hlist_node *p; struct net_device *dev; struct hlist_head *head = dev_name_hash(net, name); hlist_for_each_entry(dev, p, 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 hlist_node *p; struct net_device *dev; struct hlist_head *head = dev_name_hash(net, name); hlist_for_each_entry_rcu(dev, p, 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 hlist_node *p; struct net_device *dev; struct hlist_head *head = dev_index_hash(net, ifindex); hlist_for_each_entry(dev, p, 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 hlist_node *p; struct net_device *dev; struct hlist_head *head = dev_index_hash(net, ifindex); hlist_for_each_entry_rcu(dev, p, 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_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_rcu - 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 * rcu_read_lock(), and result refcount is unchanged. */ struct net_device *dev_get_by_flags_rcu(struct net *net, unsigned short if_flags, unsigned short mask) { struct net_device *dev, *ret; ret = NULL; for_each_netdev_rcu(net, dev) { if (((dev->flags ^ if_flags) & mask) == 0) { ret = dev; break; } } return ret; } EXPORT_SYMBOL(dev_get_by_flags_rcu); /** * 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 (strlen(name) >= IFNAMSIZ) return false; if (!strcmp(name, ".") || !strcmp(name, "..")) return false; while (*name) { if (*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; } static 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; } /** * 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) { 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; write_seqcount_begin(&devnet_rename_seq); if (strncmp(newname, dev->name, IFNAMSIZ) == 0) { write_seqcount_end(&devnet_rename_seq); return 0; } memcpy(oldname, dev->name, IFNAMSIZ); err = dev_get_valid_name(net, dev, newname); if (err < 0) { write_seqcount_end(&devnet_rename_seq); return err; } rollback: ret = device_rename(&dev->dev, dev->name); if (ret) { memcpy(dev->name, oldname, IFNAMSIZ); write_seqcount_end(&devnet_rename_seq); return ret; } write_seqcount_end(&devnet_rename_seq); 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; write_seqcount_begin(&devnet_rename_seq); memcpy(dev->name, oldname, IFNAMSIZ); 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; strlcpy(dev->ifalias, alias, len+1); 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) { call_netdevice_notifiers(NETDEV_CHANGE, dev); rtmsg_ifinfo(RTM_NEWLINK, dev, 0); } } 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); rtnl_unlock(); } EXPORT_SYMBOL(netdev_notify_peers); /** * dev_load - load a network module * @net: the applicable net namespace * @name: name of interface * * If a network interface is not present and the process has suitable * privileges this function loads the module. If module loading is not * available in this kernel then it becomes a nop. */ void dev_load(struct net *net, const char *name) { struct net_device *dev; int no_module; rcu_read_lock(); dev = dev_get_by_name_rcu(net, name); rcu_read_unlock(); no_module = !dev; if (no_module && capable(CAP_NET_ADMIN)) no_module = request_module("netdev-%s", name); if (no_module && capable(CAP_SYS_MODULE)) { if (!request_module("%s", name)) pr_warn("Loading kernel module for a network device with CAP_SYS_MODULE (deprecated). Use CAP_NET_ADMIN and alias netdev-%s instead.\n", name); } } EXPORT_SYMBOL(dev_load); 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; 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); if (ret) clear_bit(__LINK_STATE_START, &dev->state); else { dev->flags |= IFF_UP; net_dmaengine_get(); 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); 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, unreg_list) { 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_clear_bit(); /* Commit netif_running(). */ } dev_deactivate_many(head); list_for_each_entry(dev, head, unreg_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; net_dmaengine_put(); } return 0; } static int __dev_close(struct net_device *dev) { int retval; LIST_HEAD(single); list_add(&dev->unreg_list, &single); retval = __dev_close_many(&single); list_del(&single); return retval; } static int dev_close_many(struct list_head *head) { struct net_device *dev, *tmp; LIST_HEAD(tmp_list); list_for_each_entry_safe(dev, tmp, head, unreg_list) if (!(dev->flags & IFF_UP)) list_move(&dev->unreg_list, &tmp_list); __dev_close_many(head); list_for_each_entry(dev, head, unreg_list) { rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP|IFF_RUNNING); call_netdevice_notifiers(NETDEV_DOWN, dev); } /* rollback_registered_many needs the complete original list */ list_splice(&tmp_list, head); return 0; } /** * 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->unreg_list, &single); dev_close_many(&single); 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) { /* * If we're trying to disable lro on a vlan device * use the underlying physical device instead */ if (is_vlan_dev(dev)) dev = vlan_dev_real_dev(dev); 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"); } EXPORT_SYMBOL(dev_disable_lro); 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 = nb->notifier_call(nb, NETDEV_REGISTER, dev); err = notifier_to_errno(err); if (err) goto rollback; if (!(dev->flags & IFF_UP)) continue; nb->notifier_call(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) { nb->notifier_call(nb, NETDEV_GOING_DOWN, dev); nb->notifier_call(nb, NETDEV_DOWN, dev); } nb->notifier_call(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) { nb->notifier_call(nb, NETDEV_GOING_DOWN, dev); nb->notifier_call(nb, NETDEV_DOWN, dev); } nb->notifier_call(nb, NETDEV_UNREGISTER, dev); } } unlock: rtnl_unlock(); return err; } EXPORT_SYMBOL(unregister_netdevice_notifier); /** * 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) { ASSERT_RTNL(); return raw_notifier_call_chain(&netdev_chain, val, dev); } EXPORT_SYMBOL(call_netdevice_notifiers); static struct static_key netstamp_needed __read_mostly; #ifdef HAVE_JUMP_LABEL /* We are not allowed to call static_key_slow_dec() from irq context * If net_disable_timestamp() is called from irq context, defer the * static_key_slow_dec() calls. */ static atomic_t netstamp_needed_deferred; #endif void net_enable_timestamp(void) { #ifdef HAVE_JUMP_LABEL int deferred = atomic_xchg(&netstamp_needed_deferred, 0); if (deferred) { while (--deferred) static_key_slow_dec(&netstamp_needed); return; } #endif WARN_ON(in_interrupt()); static_key_slow_inc(&netstamp_needed); } EXPORT_SYMBOL(net_enable_timestamp); void net_disable_timestamp(void) { #ifdef HAVE_JUMP_LABEL if (in_interrupt()) { atomic_inc(&netstamp_needed_deferred); return; } #endif static_key_slow_dec(&netstamp_needed); } 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); \ } \ static int net_hwtstamp_validate(struct ifreq *ifr) { struct hwtstamp_config cfg; enum hwtstamp_tx_types tx_type; enum hwtstamp_rx_filters rx_filter; int tx_type_valid = 0; int rx_filter_valid = 0; if (copy_from_user(&cfg, ifr->ifr_data, sizeof(cfg))) return -EFAULT; if (cfg.flags) /* reserved for future extensions */ return -EINVAL; tx_type = cfg.tx_type; rx_filter = cfg.rx_filter; switch (tx_type) { case HWTSTAMP_TX_OFF: case HWTSTAMP_TX_ON: case HWTSTAMP_TX_ONESTEP_SYNC: tx_type_valid = 1; break; } switch (rx_filter) { case HWTSTAMP_FILTER_NONE: case HWTSTAMP_FILTER_ALL: case HWTSTAMP_FILTER_SOME: case HWTSTAMP_FILTER_PTP_V1_L4_EVENT: case HWTSTAMP_FILTER_PTP_V1_L4_SYNC: case HWTSTAMP_FILTER_PTP_V1_L4_DELAY_REQ: case HWTSTAMP_FILTER_PTP_V2_L4_EVENT: case HWTSTAMP_FILTER_PTP_V2_L4_SYNC: case HWTSTAMP_FILTER_PTP_V2_L4_DELAY_REQ: case HWTSTAMP_FILTER_PTP_V2_L2_EVENT: case HWTSTAMP_FILTER_PTP_V2_L2_SYNC: case HWTSTAMP_FILTER_PTP_V2_L2_DELAY_REQ: case HWTSTAMP_FILTER_PTP_V2_EVENT: case HWTSTAMP_FILTER_PTP_V2_SYNC: case HWTSTAMP_FILTER_PTP_V2_DELAY_REQ: rx_filter_valid = 1; break; } if (!tx_type_valid || !rx_filter_valid) return -ERANGE; return 0; } static inline bool is_skb_forwardable(struct net_device *dev, 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; } /** * 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) { if (skb_shinfo(skb)->tx_flags & SKBTX_DEV_ZEROCOPY) { if (skb_copy_ubufs(skb, GFP_ATOMIC)) { atomic_long_inc(&dev->rx_dropped); kfree_skb(skb); return NET_RX_DROP; } } skb_orphan(skb); nf_reset(skb); if (unlikely(!is_skb_forwardable(dev, skb))) { atomic_long_inc(&dev->rx_dropped); kfree_skb(skb); return NET_RX_DROP; } skb->skb_iif = 0; skb->dev = dev; skb_dst_drop(skb); skb->tstamp.tv64 = 0; skb->pkt_type = PACKET_HOST; skb->protocol = eth_type_trans(skb, dev); skb->mark = 0; secpath_reset(skb); nf_reset(skb); return netif_rx(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(skb, GFP_ATOMIC))) return -ENOMEM; atomic_inc(&skb->users); return pt_prev->func(skb, skb->dev, pt_prev, orig_dev); } 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. */ static 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; rcu_read_lock(); list_for_each_entry_rcu(ptype, &ptype_all, list) { /* Never send packets back to the socket * they originated from - MvS (miquels@drinkel.ow.org) */ if ((ptype->dev == dev || !ptype->dev) && (!skb_loop_sk(ptype, skb))) { if (pt_prev) { deliver_skb(skb2, pt_prev, skb->dev); pt_prev = ptype; continue; } skb2 = skb_clone(skb, GFP_ATOMIC); if (!skb2) break; 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 || skb2->network_header > skb2->tail) { 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 (pt_prev) pt_prev->func(skb2, skb->dev, pt_prev, skb->dev); rcu_read_unlock(); } /** * 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); } } } /* * 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) { int rc; 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); if (txq < dev->real_num_tx_queues) qdisc_reset_all_tx_gt(dev, txq); } dev->real_num_tx_queues = txq; return 0; } EXPORT_SYMBOL(netif_set_real_num_tx_queues); #ifdef CONFIG_RPS /** * 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 min_t(int, DEFAULT_MAX_NUM_RSS_QUEUES, num_online_cpus()); } EXPORT_SYMBOL(netif_get_num_default_rss_queues); static inline void __netif_reschedule(struct Qdisc *q) { struct softnet_data *sd; unsigned long flags; local_irq_save(flags); sd = &__get_cpu_var(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); void dev_kfree_skb_irq(struct sk_buff *skb) { if (atomic_dec_and_test(&skb->users)) { struct softnet_data *sd; unsigned long flags; local_irq_save(flags); sd = &__get_cpu_var(softnet_data); skb->next = sd->completion_queue; sd->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) { if (in_irq() || irqs_disabled()) dev_kfree_skb_irq(skb); 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); static void skb_warn_bad_offload(const struct sk_buff *skb) { static const netdev_features_t null_features = 0; struct net_device *dev = skb->dev; const char *driver = ""; if (dev && dev->dev.parent) driver = dev_driver_string(dev->dev.parent); WARN(1, "%s: caps=(%pNF, %pNF) len=%d data_len=%d gso_size=%d " "gso_type=%d ip_summed=%d\n", driver, 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; } 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); out_set_summed: skb->ip_summed = CHECKSUM_NONE; out: return ret; } EXPORT_SYMBOL(skb_checksum_help); /** * skb_gso_segment - Perform segmentation on skb. * @skb: buffer to segment * @features: features for the output path (see dev->features) * * 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. */ struct sk_buff *skb_gso_segment(struct sk_buff *skb, netdev_features_t features) { struct sk_buff *segs = ERR_PTR(-EPROTONOSUPPORT); struct packet_offload *ptype; __be16 type = skb->protocol; int vlan_depth = ETH_HLEN; int err; while (type == htons(ETH_P_8021Q)) { struct vlan_hdr *vh; if (unlikely(!pskb_may_pull(skb, vlan_depth + VLAN_HLEN))) return ERR_PTR(-EINVAL); vh = (struct vlan_hdr *)(skb->data + vlan_depth); type = vh->h_vlan_encapsulated_proto; vlan_depth += VLAN_HLEN; } skb_reset_mac_header(skb); skb->mac_len = skb->network_header - skb->mac_header; __skb_pull(skb, skb->mac_len); if (unlikely(skb->ip_summed != CHECKSUM_PARTIAL)) { skb_warn_bad_offload(skb); if (skb_header_cloned(skb) && (err = pskb_expand_head(skb, 0, 0, GFP_ATOMIC))) return ERR_PTR(err); } rcu_read_lock(); list_for_each_entry_rcu(ptype, &offload_base, list) { if (ptype->type == type && ptype->callbacks.gso_segment) { if (unlikely(skb->ip_summed != CHECKSUM_PARTIAL)) { err = ptype->callbacks.gso_send_check(skb); segs = ERR_PTR(err); if (err || skb_gso_ok(skb, features)) break; __skb_push(skb, (skb->data - skb_network_header(skb))); } 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_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; } struct dev_gso_cb { void (*destructor)(struct sk_buff *skb); }; #define DEV_GSO_CB(skb) ((struct dev_gso_cb *)(skb)->cb) static void dev_gso_skb_destructor(struct sk_buff *skb) { struct dev_gso_cb *cb; do { struct sk_buff *nskb = skb->next; skb->next = nskb->next; nskb->next = NULL; kfree_skb(nskb); } while (skb->next); cb = DEV_GSO_CB(skb); if (cb->destructor) cb->destructor(skb); } /** * dev_gso_segment - Perform emulated hardware segmentation on skb. * @skb: buffer to segment * @features: device features as applicable to this skb * * This function segments the given skb and stores the list of segments * in skb->next. */ static int dev_gso_segment(struct sk_buff *skb, netdev_features_t features) { struct sk_buff *segs; segs = skb_gso_segment(skb, features); /* Verifying header integrity only. */ if (!segs) return 0; if (IS_ERR(segs)) return PTR_ERR(segs); skb->next = segs; DEV_GSO_CB(skb)->destructor = skb->destructor; skb->destructor = dev_gso_skb_destructor; return 0; } static bool can_checksum_protocol(netdev_features_t features, __be16 protocol) { return ((features & NETIF_F_GEN_CSUM) || ((features & NETIF_F_V4_CSUM) && protocol == htons(ETH_P_IP)) || ((features & NETIF_F_V6_CSUM) && protocol == htons(ETH_P_IPV6)) || ((features & NETIF_F_FCOE_CRC) && protocol == htons(ETH_P_FCOE))); } static netdev_features_t harmonize_features(struct sk_buff *skb, __be16 protocol, netdev_features_t features) { if (skb->ip_summed != CHECKSUM_NONE && !can_checksum_protocol(features, protocol)) { features &= ~NETIF_F_ALL_CSUM; features &= ~NETIF_F_SG; } else if (illegal_highdma(skb->dev, skb)) { features &= ~NETIF_F_SG; } return features; } netdev_features_t netif_skb_features(struct sk_buff *skb) { __be16 protocol = skb->protocol; netdev_features_t features = skb->dev->features; if (skb_shinfo(skb)->gso_segs > skb->dev->gso_max_segs) features &= ~NETIF_F_GSO_MASK; if (protocol == htons(ETH_P_8021Q)) { struct vlan_ethhdr *veh = (struct vlan_ethhdr *)skb->data; protocol = veh->h_vlan_encapsulated_proto; } else if (!vlan_tx_tag_present(skb)) { return harmonize_features(skb, protocol, features); } features &= (skb->dev->vlan_features | NETIF_F_HW_VLAN_TX); if (protocol != htons(ETH_P_8021Q)) { return harmonize_features(skb, protocol, features); } else { features &= NETIF_F_SG | NETIF_F_HIGHDMA | NETIF_F_FRAGLIST | NETIF_F_GEN_CSUM | NETIF_F_HW_VLAN_TX; return harmonize_features(skb, protocol, features); } } EXPORT_SYMBOL(netif_skb_features); /* * Returns true if either: * 1. skb has frag_list and the device doesn't support FRAGLIST, or * 2. skb is fragmented and the device does not support SG. */ static inline int skb_needs_linearize(struct sk_buff *skb, int features) { return skb_is_nonlinear(skb) && ((skb_has_frag_list(skb) && !(features & NETIF_F_FRAGLIST)) || (skb_shinfo(skb)->nr_frags && !(features & NETIF_F_SG))); } int dev_hard_start_xmit(struct sk_buff *skb, struct net_device *dev, struct netdev_queue *txq) { const struct net_device_ops *ops = dev->netdev_ops; int rc = NETDEV_TX_OK; unsigned int skb_len; if (likely(!skb->next)) { netdev_features_t features; /* * If device doesn'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); features = netif_skb_features(skb); if (vlan_tx_tag_present(skb) && !(features & NETIF_F_HW_VLAN_TX)) { skb = __vlan_put_tag(skb, vlan_tx_tag_get(skb)); if (unlikely(!skb)) goto out; skb->vlan_tci = 0; } /* 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 (netif_needs_gso(skb, features)) { if (unlikely(dev_gso_segment(skb, features))) goto out_kfree_skb; if (skb->next) goto gso; } 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_ALL_CSUM) && skb_checksum_help(skb)) goto out_kfree_skb; } } if (!list_empty(&ptype_all)) dev_queue_xmit_nit(skb, dev); skb_len = skb->len; rc = ops->ndo_start_xmit(skb, dev); trace_net_dev_xmit(skb, rc, dev, skb_len); if (rc == NETDEV_TX_OK) txq_trans_update(txq); return rc; } gso: do { struct sk_buff *nskb = skb->next; skb->next = nskb->next; nskb->next = NULL; /* * If device doesn't need nskb->dst, release it right now while * its hot in this cpu cache */ if (dev->priv_flags & IFF_XMIT_DST_RELEASE) skb_dst_drop(nskb); if (!list_empty(&ptype_all)) dev_queue_xmit_nit(nskb, dev); skb_len = nskb->len; rc = ops->ndo_start_xmit(nskb, dev); trace_net_dev_xmit(nskb, rc, dev, skb_len); if (unlikely(rc != NETDEV_TX_OK)) { if (rc & ~NETDEV_TX_MASK) goto out_kfree_gso_skb; nskb->next = skb->next; skb->next = nskb; return rc; } txq_trans_update(txq); if (unlikely(netif_xmit_stopped(txq) && skb->next)) return NETDEV_TX_BUSY; } while (skb->next); out_kfree_gso_skb: if (likely(skb->next == NULL)) skb->destructor = DEV_GSO_CB(skb)->destructor; out_kfree_skb: kfree_skb(skb); out: return rc; } static u32 hashrnd __read_mostly; /* * 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, const 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; } if (skb->sk && skb->sk->sk_hash) hash = skb->sk->sk_hash; else hash = (__force u16) skb->protocol; hash = jhash_1word(hash, hashrnd); return (u16) (((u64) hash * qcount) >> 32) + qoffset; } EXPORT_SYMBOL(__skb_tx_hash); static inline u16 dev_cap_txqueue(struct net_device *dev, u16 queue_index) { if (unlikely(queue_index >= dev->real_num_tx_queues)) { net_warn_ratelimited("%s selects TX queue %d, but real number of TX queues is %d\n", dev->name, queue_index, dev->real_num_tx_queues); return 0; } return queue_index; } 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[raw_smp_processor_id()]); if (map) { if (map->len == 1) queue_index = map->queues[0]; else { u32 hash; if (skb->sk && skb->sk->sk_hash) hash = skb->sk->sk_hash; else hash = (_