From f001fde5eadd915f4858d22ed70d7040f48767cf Mon Sep 17 00:00:00 2001 From: Jiri Pirko Date: Tue, 5 May 2009 02:48:28 +0000 Subject: [PATCH] net: introduce a list of device addresses dev_addr_list (v6) v5 -> v6 (current): -removed so far unused static functions -corrected dev_addr_del_multiple to call del instead of add v4 -> v5: -added device address type (suggested by davem) -removed refcounting (better to have simplier code then safe potentially few bytes) v3 -> v4: -changed kzalloc to kmalloc in __hw_addr_add_ii() -ASSERT_RTNL() avoided in dev_addr_flush() and dev_addr_init() v2 -> v3: -removed unnecessary rcu read locking -moved dev_addr_flush() calling to ensure no null dereference of dev_addr v1 -> v2: -added forgotten ASSERT_RTNL to dev_addr_init and dev_addr_flush -removed unnecessary rcu_read locking in dev_addr_init -use compare_ether_addr_64bits instead of compare_ether_addr -use L1_CACHE_BYTES as size for allocating struct netdev_hw_addr -use call_rcu instead of rcu_synchronize -moved is_etherdev_addr into __KERNEL__ ifdef This patch introduces a new list in struct net_device and brings a set of functions to handle the work with device address list. The list is a replacement for the original dev_addr field and because in some situations there is need to carry several device addresses with the net device. To be backward compatible, dev_addr is made to point to the first member of the list so original drivers sees no difference. Signed-off-by: Jiri Pirko Signed-off-by: David S. Miller --- include/linux/etherdevice.h | 27 ++++ include/linux/netdevice.h | 37 +++++- net/core/dev.c | 250 ++++++++++++++++++++++++++++++++++++ 3 files changed, 312 insertions(+), 2 deletions(-) diff --git a/include/linux/etherdevice.h b/include/linux/etherdevice.h index a1f17abba7dc..3d7a6687d247 100644 --- a/include/linux/etherdevice.h +++ b/include/linux/etherdevice.h @@ -182,6 +182,33 @@ static inline unsigned compare_ether_addr_64bits(const u8 addr1[6+2], return compare_ether_addr(addr1, addr2); #endif } + +/** + * is_etherdev_addr - Tell if given Ethernet address belongs to the device. + * @dev: Pointer to a device structure + * @addr: Pointer to a six-byte array containing the Ethernet address + * + * Compare passed address with all addresses of the device. Return true if the + * address if one of the device addresses. + * + * Note that this function calls compare_ether_addr_64bits() so take care of + * the right padding. + */ +static inline bool is_etherdev_addr(const struct net_device *dev, + const u8 addr[6 + 2]) +{ + struct netdev_hw_addr *ha; + int res = 1; + + rcu_read_lock(); + for_each_dev_addr(dev, ha) { + res = compare_ether_addr_64bits(addr, ha->addr); + if (!res) + break; + } + rcu_read_unlock(); + return !res; +} #endif /* __KERNEL__ */ /** diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index ff42aba403c5..02882e2ebd49 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -210,6 +210,16 @@ struct dev_addr_list #define dmi_users da_users #define dmi_gusers da_gusers +struct netdev_hw_addr { + struct list_head list; + unsigned char addr[MAX_ADDR_LEN]; + unsigned char type; +#define NETDEV_HW_ADDR_T_LAN 1 +#define NETDEV_HW_ADDR_T_SAN 2 +#define NETDEV_HW_ADDR_T_SLAVE 3 + struct rcu_head rcu_head; +}; + struct hh_cache { struct hh_cache *hh_next; /* Next entry */ @@ -784,8 +794,11 @@ struct net_device */ unsigned long last_rx; /* Time of last Rx */ /* Interface address info used in eth_type_trans() */ - unsigned char dev_addr[MAX_ADDR_LEN]; /* hw address, (before bcast - because most packets are unicast) */ + unsigned char *dev_addr; /* hw address, (before bcast + because most packets are + unicast) */ + + struct list_head dev_addr_list; /* list of device hw addresses */ unsigned char broadcast[MAX_ADDR_LEN]; /* hw bcast add */ @@ -1791,6 +1804,13 @@ static inline void netif_addr_unlock_bh(struct net_device *dev) spin_unlock_bh(&dev->addr_list_lock); } +/* + * dev_addr_list walker. Should be used only for read access. Call with + * rcu_read_lock held. + */ +#define for_each_dev_addr(dev, ha) \ + list_for_each_entry_rcu(ha, &dev->dev_addr_list, list) + /* These functions live elsewhere (drivers/net/net_init.c, but related) */ extern void ether_setup(struct net_device *dev); @@ -1803,6 +1823,19 @@ extern struct net_device *alloc_netdev_mq(int sizeof_priv, const char *name, alloc_netdev_mq(sizeof_priv, name, setup, 1) extern int register_netdev(struct net_device *dev); extern void unregister_netdev(struct net_device *dev); + +/* Functions used for device addresses handling */ +extern int dev_addr_add(struct net_device *dev, unsigned char *addr, + unsigned char addr_type); +extern int dev_addr_del(struct net_device *dev, unsigned char *addr, + unsigned char addr_type); +extern int dev_addr_add_multiple(struct net_device *to_dev, + struct net_device *from_dev, + unsigned char addr_type); +extern int dev_addr_del_multiple(struct net_device *to_dev, + struct net_device *from_dev, + unsigned char addr_type); + /* Functions used for secondary unicast and multicast support */ extern void dev_set_rx_mode(struct net_device *dev); extern void __dev_set_rx_mode(struct net_device *dev); diff --git a/net/core/dev.c b/net/core/dev.c index 3c8073fe970a..637ea71b0a0d 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -3434,6 +3434,252 @@ void dev_set_rx_mode(struct net_device *dev) netif_addr_unlock_bh(dev); } +/* hw addresses list handling functions */ + +static int __hw_addr_add(struct list_head *list, unsigned char *addr, + int addr_len, unsigned char addr_type) +{ + struct netdev_hw_addr *ha; + int alloc_size; + + if (addr_len > MAX_ADDR_LEN) + return -EINVAL; + + alloc_size = sizeof(*ha); + if (alloc_size < L1_CACHE_BYTES) + alloc_size = L1_CACHE_BYTES; + ha = kmalloc(alloc_size, GFP_ATOMIC); + if (!ha) + return -ENOMEM; + memcpy(ha->addr, addr, addr_len); + ha->type = addr_type; + list_add_tail_rcu(&ha->list, list); + return 0; +} + +static void ha_rcu_free(struct rcu_head *head) +{ + struct netdev_hw_addr *ha; + + ha = container_of(head, struct netdev_hw_addr, rcu_head); + kfree(ha); +} + +static int __hw_addr_del_ii(struct list_head *list, unsigned char *addr, + int addr_len, unsigned char addr_type, + int ignore_index) +{ + struct netdev_hw_addr *ha; + int i = 0; + + list_for_each_entry(ha, list, list) { + if (i++ != ignore_index && + !memcmp(ha->addr, addr, addr_len) && + (ha->type == addr_type || !addr_type)) { + list_del_rcu(&ha->list); + call_rcu(&ha->rcu_head, ha_rcu_free); + return 0; + } + } + return -ENOENT; +} + +static int __hw_addr_add_multiple_ii(struct list_head *to_list, + struct list_head *from_list, + int addr_len, unsigned char addr_type, + int ignore_index) +{ + int err; + struct netdev_hw_addr *ha, *ha2; + unsigned char type; + + list_for_each_entry(ha, from_list, list) { + type = addr_type ? addr_type : ha->type; + err = __hw_addr_add(to_list, ha->addr, addr_len, type); + if (err) + goto unroll; + } + return 0; + +unroll: + list_for_each_entry(ha2, from_list, list) { + if (ha2 == ha) + break; + type = addr_type ? addr_type : ha2->type; + __hw_addr_del_ii(to_list, ha2->addr, addr_len, type, + ignore_index); + } + return err; +} + +static void __hw_addr_del_multiple_ii(struct list_head *to_list, + struct list_head *from_list, + int addr_len, unsigned char addr_type, + int ignore_index) +{ + struct netdev_hw_addr *ha; + unsigned char type; + + list_for_each_entry(ha, from_list, list) { + type = addr_type ? addr_type : ha->type; + __hw_addr_del_ii(to_list, ha->addr, addr_len, addr_type, + ignore_index); + } +} + +static void __hw_addr_flush(struct list_head *list) +{ + struct netdev_hw_addr *ha, *tmp; + + list_for_each_entry_safe(ha, tmp, list, list) { + list_del_rcu(&ha->list); + call_rcu(&ha->rcu_head, ha_rcu_free); + } +} + +/* Device addresses handling functions */ + +static void dev_addr_flush(struct net_device *dev) +{ + /* rtnl_mutex must be held here */ + + __hw_addr_flush(&dev->dev_addr_list); + dev->dev_addr = NULL; +} + +static int dev_addr_init(struct net_device *dev) +{ + unsigned char addr[MAX_ADDR_LEN]; + struct netdev_hw_addr *ha; + int err; + + /* rtnl_mutex must be held here */ + + INIT_LIST_HEAD(&dev->dev_addr_list); + memset(addr, 0, sizeof(*addr)); + err = __hw_addr_add(&dev->dev_addr_list, addr, sizeof(*addr), + NETDEV_HW_ADDR_T_LAN); + if (!err) { + /* + * Get the first (previously created) address from the list + * and set dev_addr pointer to this location. + */ + ha = list_first_entry(&dev->dev_addr_list, + struct netdev_hw_addr, list); + dev->dev_addr = ha->addr; + } + return err; +} + +/** + * dev_addr_add - Add a device address + * @dev: device + * @addr: address to add + * @addr_type: address type + * + * Add a device address to the device or increase the reference count if + * it already exists. + * + * The caller must hold the rtnl_mutex. + */ +int dev_addr_add(struct net_device *dev, unsigned char *addr, + unsigned char addr_type) +{ + int err; + + ASSERT_RTNL(); + + err = __hw_addr_add(&dev->dev_addr_list, addr, dev->addr_len, + addr_type); + if (!err) + call_netdevice_notifiers(NETDEV_CHANGEADDR, dev); + return err; +} +EXPORT_SYMBOL(dev_addr_add); + +/** + * dev_addr_del - Release a device address. + * @dev: device + * @addr: address to delete + * @addr_type: address type + * + * Release reference to a device address and remove it from the device + * if the reference count drops to zero. + * + * The caller must hold the rtnl_mutex. + */ +int dev_addr_del(struct net_device *dev, unsigned char *addr, + unsigned char addr_type) +{ + int err; + + ASSERT_RTNL(); + + err = __hw_addr_del_ii(&dev->dev_addr_list, addr, dev->addr_len, + addr_type, 0); + if (!err) + call_netdevice_notifiers(NETDEV_CHANGEADDR, dev); + return err; +} +EXPORT_SYMBOL(dev_addr_del); + +/** + * dev_addr_add_multiple - Add device addresses from another device + * @to_dev: device to which addresses will be added + * @from_dev: device from which addresses will be added + * @addr_type: address type - 0 means type will be used from from_dev + * + * Add device addresses of the one device to another. + ** + * The caller must hold the rtnl_mutex. + */ +int dev_addr_add_multiple(struct net_device *to_dev, + struct net_device *from_dev, + unsigned char addr_type) +{ + int err; + + ASSERT_RTNL(); + + if (from_dev->addr_len != to_dev->addr_len) + return -EINVAL; + err = __hw_addr_add_multiple_ii(&to_dev->dev_addr_list, + &from_dev->dev_addr_list, + to_dev->addr_len, addr_type, 0); + if (!err) + call_netdevice_notifiers(NETDEV_CHANGEADDR, to_dev); + return err; +} +EXPORT_SYMBOL(dev_addr_add_multiple); + +/** + * dev_addr_del_multiple - Delete device addresses by another device + * @to_dev: device where the addresses will be deleted + * @from_dev: device by which addresses the addresses will be deleted + * @addr_type: address type - 0 means type will used from from_dev + * + * Deletes addresses in to device by the list of addresses in from device. + * + * The caller must hold the rtnl_mutex. + */ +int dev_addr_del_multiple(struct net_device *to_dev, + struct net_device *from_dev, + unsigned char addr_type) +{ + ASSERT_RTNL(); + + if (from_dev->addr_len != to_dev->addr_len) + return -EINVAL; + __hw_addr_del_multiple_ii(&to_dev->dev_addr_list, + &from_dev->dev_addr_list, + to_dev->addr_len, addr_type, 0); + call_netdevice_notifiers(NETDEV_CHANGEADDR, to_dev); + return 0; +} +EXPORT_SYMBOL(dev_addr_del_multiple); + +/* unicast and multicast addresses handling functions */ + int __dev_addr_delete(struct dev_addr_list **list, int *count, void *addr, int alen, int glbl) { @@ -4776,6 +5022,7 @@ struct net_device *alloc_netdev_mq(int sizeof_priv, const char *name, dev->gso_max_size = GSO_MAX_SIZE; + dev_addr_init(dev); netdev_init_queues(dev); INIT_LIST_HEAD(&dev->napi_list); @@ -4801,6 +5048,9 @@ void free_netdev(struct net_device *dev) kfree(dev->_tx); + /* Flush device addresses */ + dev_addr_flush(dev); + list_for_each_entry_safe(p, n, &dev->napi_list, dev_list) netif_napi_del(p); -- 2.30.2