| Message ID | 20090415180215.GA22540@psychotron.englab.brq.redhat.com |
|---|---|
| State | RFC, archived |
| Delegated to: | David Miller |
| Headers | show |
Jiri Pirko a écrit : > changes against last patch version: > -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 <jpirko@redhat.com> > --- > include/linux/etherdevice.h | 27 +++++ > include/linux/netdevice.h | 32 +++++- > net/core/dev.c | 271 +++++++++++++++++++++++++++++++++++++++++++ > 3 files changed, 328 insertions(+), 2 deletions(-) > > diff --git a/include/linux/etherdevice.h b/include/linux/etherdevice.h > index a1f17ab..3d7a668 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 2e7783f..89ad6d2 100644 > --- a/include/linux/netdevice.h > +++ b/include/linux/netdevice.h > @@ -210,6 +210,13 @@ 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]; > + int refcount; > + struct rcu_head rcu_head; > +}; > + > struct hh_cache > { > struct hh_cache *hh_next; /* Next entry */ > @@ -776,8 +783,11 @@ 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 */ > > @@ -1778,6 +1788,13 @@ 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); > @@ -1790,6 +1807,17 @@ 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); > +extern int dev_addr_del(struct net_device *dev, > + unsigned char *addr); > +extern int dev_addr_add_multiple(struct net_device *to_dev, > + struct net_device *from_dev); > +extern int dev_addr_del_multiple(struct net_device *to_dev, > + struct net_device *from_dev); > + > /* 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 91d792d..961be4f 100644 > --- a/net/core/dev.c > +++ b/net/core/dev.c > @@ -3437,6 +3437,270 @@ void dev_set_rx_mode(struct net_device *dev) > netif_addr_unlock_bh(dev); > } > > +/* hw addresses list handling functions */ > + > +static int __hw_addr_add_ii(struct list_head *list, unsigned char *addr, > + int addr_len, int ignore_index) > +{ > + struct netdev_hw_addr *ha; > + int i = 0; > + > + if (addr_len > MAX_ADDR_LEN) > + return -EINVAL; > + Please put here the ASSERT_RTNL(), not in various callers, since this is the place where we really assume rtnl lock is locked by us. You still use rcu_read_lock()/unlock() and rcu variant here... But caller of this function has RTNL (or other lock) so dont use rcu here, as it seems inconsistent with kzalloc() code that comes next. > + rcu_read_lock(); > + list_for_each_entry_rcu(ha, list, list) { > + if (i++ != ignore_index && > + !memcmp(ha->addr, addr, addr_len)) { > + ha->refcount++; > + rcu_read_unlock(); > + return 0; > + } > + } > + rcu_read_unlock(); > + > + ha = kzalloc(max(sizeof(*ha), L1_CACHE_BYTES), GFP_ATOMIC); > + if (!ha) > + return -ENOMEM; > + memcpy(ha->addr, addr, addr_len); > + ha->refcount = 1; > + list_add_tail_rcu(&ha->list, list); > + return 0; > +} > + > +static int __hw_addr_add(struct list_head *list, unsigned char *addr, > + int addr_len) > +{ > + return __hw_addr_add_ii(list, addr, addr_len, -1); > +} > + > +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, int ignore_index) > +{ > + struct netdev_hw_addr *ha; > + int i = 0; > + ASSERT_RTNL() here, not in callers. > + list_for_each_entry(ha, list, list) { > + if (i++ != ignore_index && > + !memcmp(ha->addr, addr, addr_len)) { > + if (--ha->refcount) > + return 0; > + list_del_rcu(&ha->list); > + call_rcu(&ha->rcu_head, ha_rcu_free); > + return 0; > + } > + } > + return -ENOENT; > +} > + > +static int __hw_addr_del(struct list_head *list, unsigned char *addr, > + int addr_len) > +{ > + return __hw_addr_del_ii(list, addr, addr_len, -1); > +} > + > +static int __hw_addr_add_multiple_ii(struct list_head *to_list, > + struct list_head *from_list, > + int addr_len, int ignore_index) > +{ > + int err = 0; > + struct netdev_hw_addr *ha, *ha2; > + same here, no need for rcu_read_lock(), since you are going to change list, you have RTNL lock or equivalent. > + rcu_read_lock(); > + list_for_each_entry_rcu(ha, from_list, list) { > + err = __hw_addr_add_ii(to_list, ha->addr, addr_len, 0); > + if (err) > + goto unroll; > + } > + goto unlock; > +unroll: > + list_for_each_entry_rcu(ha2, from_list, list) { > + if (ha2 == ha) > + break; > + __hw_addr_del_ii(to_list, ha2->addr, addr_len, 0); > + } > +unlock: > + rcu_read_unlock(); > + return err; > +} > + > +static int __hw_addr_add_multiple(struct list_head *to_list, > + struct list_head *from_list, > + int addr_len) > +{ > + return __hw_addr_add_multiple_ii(to_list, from_list, addr_len, -1); > +} > + > +static void __hw_addr_del_multiple_ii(struct list_head *to_list, > + struct list_head *from_list, > + int addr_len, int ignore_index) > +{ > + struct netdev_hw_addr *ha; > + same here, no rcu_read_lock() needed... > + rcu_read_lock(); > + list_for_each_entry_rcu(ha, from_list, list) { > + __hw_addr_del_ii(to_list, ha->addr, addr_len, 0); > + } > + rcu_read_unlock(); > +} > + > +static void __hw_addr_del_multiple(struct list_head *to_list, > + struct list_head *from_list, > + int addr_len) > +{ > + __hw_addr_del_multiple_ii(to_list, from_list, addr_len, -1); > +} > + > +static void __hw_addr_flush(struct list_head *list) > +{ > + struct netdev_hw_addr *ha, *tmp; > + ASSERT_RTNL(); > + 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) > +{ > + ASSERT_RTNL(); > + > + __hw_addr_flush(&dev->dev_addr_list); > + dev->dev_addr = NULL; seems risky here to set this to NULL... You could use a static var to avoid further NULL dereference. static char nulladdr[MAX_ADDR_LEN]; dev->dev_addr = nulladdr; > +} > + > +static int dev_addr_init(struct net_device *dev) > +{ > + unsigned char addr[MAX_ADDR_LEN]; > + struct netdev_hw_addr *ha; > + int err; > + > + ASSERT_RTNL(); > + > + INIT_LIST_HEAD(&dev->dev_addr_list); > + memset(addr, 0, sizeof(*addr)); > + err = __hw_addr_add(&dev->dev_addr_list, addr, sizeof(*addr)); > + 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 > + * > + * 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) > +{ > + int err; > + > + ASSERT_RTNL(); > + > + err = __hw_addr_add_ii(&dev->dev_addr_list, addr, dev->addr_len, 0); > + 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 > + * > + * 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) > +{ > + int err; > + > + ASSERT_RTNL(); > + > + err = __hw_addr_del_ii(&dev->dev_addr_list, addr, dev->addr_len, 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 > + * > + * 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) > +{ > + 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, 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 > + * > + * 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) > +{ > + ASSERT_RTNL(); > + > + if (from_dev->addr_len != to_dev->addr_len) > + return -EINVAL; > + __hw_addr_add_multiple_ii(&to_dev->dev_addr_list, > + &from_dev->dev_addr_list, > + to_dev->addr_len, 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) > { > @@ -4257,6 +4521,9 @@ static void rollback_registered(struct net_device *dev) > */ > dev_addr_discard(dev); > > + /* Flush device addresses */ > + dev_addr_flush(dev); > + Are you sure that no driver in tree will dereference dev->dev_addr after this point ? > if (dev->netdev_ops->ndo_uninit) > dev->netdev_ops->ndo_uninit(dev); > > @@ -4779,6 +5046,7 @@ 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); > @@ -4965,6 +5233,9 @@ int dev_change_net_namespace(struct net_device *dev, struct net *net, const char > */ > dev_addr_discard(dev); > > + /* Flush device addresses */ > + dev_addr_flush(dev); > + > netdev_unregister_kobject(dev); > > /* Actually switch the network namespace */ -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Wed, Apr 15, 2009 at 08:54:05PM CEST, dada1@cosmosbay.com wrote: >Jiri Pirko a écrit : <snip> >> +static int __hw_addr_add_ii(struct list_head *list, unsigned char *addr, >> + int addr_len, int ignore_index) >> +{ >> + struct netdev_hw_addr *ha; >> + int i = 0; >> + >> + if (addr_len > MAX_ADDR_LEN) >> + return -EINVAL; >> + > >Please put here the ASSERT_RTNL(), not in various callers, since >this is the place where we really assume rtnl lock is locked by us. Well I'd like to have ASSERT_RTNL in callers. The reason is that for this purpose (dev_addr) the guarding lock is rtnl. But for example for multicast addresses it won't be. It will be most probably a spin lock. But those callers (multicast) will use this __hw_addr_xxx functions too. Therefore I'd like to leave locking on current level. > >You still use rcu_read_lock()/unlock() and rcu variant here... Yes this is unecessrary and confusing I agree. Will remove these read locks in places where there is guarded by rtnl mutex. > >But caller of this function has RTNL (or other lock) so dont use rcu here, as it seems >inconsistent with kzalloc() code that comes next. > >> + rcu_read_lock(); >> + list_for_each_entry_rcu(ha, list, list) { >> + if (i++ != ignore_index && >> + !memcmp(ha->addr, addr, addr_len)) { >> + ha->refcount++; >> + rcu_read_unlock(); >> + return 0; >> + } >> + } >> + rcu_read_unlock(); >> + >> + ha = kzalloc(max(sizeof(*ha), L1_CACHE_BYTES), GFP_ATOMIC); >> + if (!ha) >> + return -ENOMEM; >> + memcpy(ha->addr, addr, addr_len); >> + ha->refcount = 1; >> + list_add_tail_rcu(&ha->list, list); >> + return 0; <snip> >> +static int __hw_addr_add_multiple_ii(struct list_head *to_list, >> + struct list_head *from_list, >> + int addr_len, int ignore_index) >> +{ >> + int err = 0; >> + struct netdev_hw_addr *ha, *ha2; >> + > >same here, no need for rcu_read_lock(), since you are going to change list, you >have RTNL lock or equivalent. > Yes, I wanted to show that for "from_list" this is a reader... ....unnecessary,foolish -> removing... >> + rcu_read_lock(); >> + list_for_each_entry_rcu(ha, from_list, list) { >> + err = __hw_addr_add_ii(to_list, ha->addr, addr_len, 0); >> + if (err) >> + goto unroll; >> + } >> + goto unlock; >> +unroll: >> + list_for_each_entry_rcu(ha2, from_list, list) { >> + if (ha2 == ha) >> + break; >> + __hw_addr_del_ii(to_list, ha2->addr, addr_len, 0); >> + } >> +unlock: >> + rcu_read_unlock(); >> + return err; >> +} >> + <snip> >> +static void dev_addr_flush(struct net_device *dev) >> +{ >> + ASSERT_RTNL(); >> + >> + __hw_addr_flush(&dev->dev_addr_list); >> + dev->dev_addr = NULL; > >seems risky here to set this to NULL... You could use a static var to avoid >further NULL dereference. > >static char nulladdr[MAX_ADDR_LEN]; >dev->dev_addr = nulladdr; > >> +} >> + <snip> >> @@ -4257,6 +4521,9 @@ static void rollback_registered(struct net_device *dev) >> */ >> dev_addr_discard(dev); >> >> + /* Flush device addresses */ >> + dev_addr_flush(dev); >> + > >Are you sure that no driver in tree will dereference dev->dev_addr after this point ? I assume that driver might not use dev_addr after it calls unregister_netdevice(). But ok - I would rather move calling dev_addr_flush() somewhere later where there is a guarantee that dev_addr should not be referenced. Perhaps in free_netdev() ? It would also correspond with calling dev_addr_init() in alloc_netdev_mq()... > >> if (dev->netdev_ops->ndo_uninit) >> dev->netdev_ops->ndo_uninit(dev); >> >> @@ -4779,6 +5046,7 @@ 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); >> @@ -4965,6 +5233,9 @@ int dev_change_net_namespace(struct net_device *dev, struct net *net, const char >> */ >> dev_addr_discard(dev); >> >> + /* Flush device addresses */ >> + dev_addr_flush(dev); >> + >> netdev_unregister_kobject(dev); >> >> /* Actually switch the network namespace */ > > -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/include/linux/etherdevice.h b/include/linux/etherdevice.h index a1f17ab..3d7a668 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 2e7783f..89ad6d2 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -210,6 +210,13 @@ 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]; + int refcount; + struct rcu_head rcu_head; +}; + struct hh_cache { struct hh_cache *hh_next; /* Next entry */ @@ -776,8 +783,11 @@ 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 */ @@ -1778,6 +1788,13 @@ 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); @@ -1790,6 +1807,17 @@ 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); +extern int dev_addr_del(struct net_device *dev, + unsigned char *addr); +extern int dev_addr_add_multiple(struct net_device *to_dev, + struct net_device *from_dev); +extern int dev_addr_del_multiple(struct net_device *to_dev, + struct net_device *from_dev); + /* 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 91d792d..961be4f 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -3437,6 +3437,270 @@ void dev_set_rx_mode(struct net_device *dev) netif_addr_unlock_bh(dev); } +/* hw addresses list handling functions */ + +static int __hw_addr_add_ii(struct list_head *list, unsigned char *addr, + int addr_len, int ignore_index) +{ + struct netdev_hw_addr *ha; + int i = 0; + + if (addr_len > MAX_ADDR_LEN) + return -EINVAL; + + rcu_read_lock(); + list_for_each_entry_rcu(ha, list, list) { + if (i++ != ignore_index && + !memcmp(ha->addr, addr, addr_len)) { + ha->refcount++; + rcu_read_unlock(); + return 0; + } + } + rcu_read_unlock(); + + ha = kzalloc(max(sizeof(*ha), L1_CACHE_BYTES), GFP_ATOMIC); + if (!ha) + return -ENOMEM; + memcpy(ha->addr, addr, addr_len); + ha->refcount = 1; + list_add_tail_rcu(&ha->list, list); + return 0; +} + +static int __hw_addr_add(struct list_head *list, unsigned char *addr, + int addr_len) +{ + return __hw_addr_add_ii(list, addr, addr_len, -1); +} + +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, 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)) { + if (--ha->refcount) + return 0; + list_del_rcu(&ha->list); + call_rcu(&ha->rcu_head, ha_rcu_free); + return 0; + } + } + return -ENOENT; +} + +static int __hw_addr_del(struct list_head *list, unsigned char *addr, + int addr_len) +{ + return __hw_addr_del_ii(list, addr, addr_len, -1); +} + +static int __hw_addr_add_multiple_ii(struct list_head *to_list, + struct list_head *from_list, + int addr_len, int ignore_index) +{ + int err = 0; + struct netdev_hw_addr *ha, *ha2; + + rcu_read_lock(); + list_for_each_entry_rcu(ha, from_list, list) { + err = __hw_addr_add_ii(to_list, ha->addr, addr_len, 0); + if (err) + goto unroll; + } + goto unlock; +unroll: + list_for_each_entry_rcu(ha2, from_list, list) { + if (ha2 == ha) + break; + __hw_addr_del_ii(to_list, ha2->addr, addr_len, 0); + } +unlock: + rcu_read_unlock(); + return err; +} + +static int __hw_addr_add_multiple(struct list_head *to_list, + struct list_head *from_list, + int addr_len) +{ + return __hw_addr_add_multiple_ii(to_list, from_list, addr_len, -1); +} + +static void __hw_addr_del_multiple_ii(struct list_head *to_list, + struct list_head *from_list, + int addr_len, int ignore_index) +{ + struct netdev_hw_addr *ha; + + rcu_read_lock(); + list_for_each_entry_rcu(ha, from_list, list) { + __hw_addr_del_ii(to_list, ha->addr, addr_len, 0); + } + rcu_read_unlock(); +} + +static void __hw_addr_del_multiple(struct list_head *to_list, + struct list_head *from_list, + int addr_len) +{ + __hw_addr_del_multiple_ii(to_list, from_list, addr_len, -1); +} + +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) +{ + ASSERT_RTNL(); + + __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; + + ASSERT_RTNL(); + + INIT_LIST_HEAD(&dev->dev_addr_list); + memset(addr, 0, sizeof(*addr)); + err = __hw_addr_add(&dev->dev_addr_list, addr, sizeof(*addr)); + 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 + * + * 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) +{ + int err; + + ASSERT_RTNL(); + + err = __hw_addr_add_ii(&dev->dev_addr_list, addr, dev->addr_len, 0); + 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 + * + * 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) +{ + int err; + + ASSERT_RTNL(); + + err = __hw_addr_del_ii(&dev->dev_addr_list, addr, dev->addr_len, 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 + * + * 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) +{ + 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, 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 + * + * 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) +{ + ASSERT_RTNL(); + + if (from_dev->addr_len != to_dev->addr_len) + return -EINVAL; + __hw_addr_add_multiple_ii(&to_dev->dev_addr_list, + &from_dev->dev_addr_list, + to_dev->addr_len, 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) { @@ -4257,6 +4521,9 @@ static void rollback_registered(struct net_device *dev) */ dev_addr_discard(dev); + /* Flush device addresses */ + dev_addr_flush(dev); + if (dev->netdev_ops->ndo_uninit) dev->netdev_ops->ndo_uninit(dev); @@ -4779,6 +5046,7 @@ 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); @@ -4965,6 +5233,9 @@ int dev_change_net_namespace(struct net_device *dev, struct net *net, const char */ dev_addr_discard(dev); + /* Flush device addresses */ + dev_addr_flush(dev); + netdev_unregister_kobject(dev); /* Actually switch the network namespace */
changes against last patch version: -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 <jpirko@redhat.com> --- include/linux/etherdevice.h | 27 +++++ include/linux/netdevice.h | 32 +++++- net/core/dev.c | 271 +++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 328 insertions(+), 2 deletions(-)