diff options
-rw-r--r-- | drivers/net/macvlan.c | 7 | ||||
-rw-r--r-- | include/linux/rculist.h | 17 |
2 files changed, 21 insertions, 3 deletions
diff --git a/drivers/net/macvlan.c b/drivers/net/macvlan.c index 956a5ed8790..71605231bcb 100644 --- a/drivers/net/macvlan.c +++ b/drivers/net/macvlan.c @@ -205,7 +205,8 @@ static rx_handler_result_t macvlan_handle_frame(struct sk_buff **pskb) } if (port->passthru) - vlan = list_first_entry(&port->vlans, struct macvlan_dev, list); + vlan = list_first_or_null_rcu(&port->vlans, + struct macvlan_dev, list); else vlan = macvlan_hash_lookup(port, eth->h_dest); if (vlan == NULL) @@ -724,7 +725,7 @@ int macvlan_common_newlink(struct net *src_net, struct net_device *dev, if (err < 0) goto destroy_port; - list_add_tail(&vlan->list, &port->vlans); + list_add_tail_rcu(&vlan->list, &port->vlans); netif_stacked_transfer_operstate(lowerdev, dev); return 0; @@ -750,7 +751,7 @@ void macvlan_dellink(struct net_device *dev, struct list_head *head) { struct macvlan_dev *vlan = netdev_priv(dev); - list_del(&vlan->list); + list_del_rcu(&vlan->list); unregister_netdevice_queue(dev, head); } EXPORT_SYMBOL_GPL(macvlan_dellink); diff --git a/include/linux/rculist.h b/include/linux/rculist.h index d079290843a..6f95e241ed6 100644 --- a/include/linux/rculist.h +++ b/include/linux/rculist.h @@ -242,6 +242,23 @@ static inline void list_splice_init_rcu(struct list_head *list, list_entry_rcu((ptr)->next, type, member) /** + * list_first_or_null_rcu - get the first element from a list + * @ptr: the list head to take the element from. + * @type: the type of the struct this is embedded in. + * @member: the name of the list_struct within the struct. + * + * Note that if the list is empty, it returns NULL. + * + * This primitive may safely run concurrently with the _rcu list-mutation + * primitives such as list_add_rcu() as long as it's guarded by rcu_read_lock(). + */ +#define list_first_or_null_rcu(ptr, type, member) \ + ({struct list_head *__ptr = (ptr); \ + struct list_head __rcu *__next = list_next_rcu(__ptr); \ + likely(__ptr != __next) ? container_of(__next, type, member) : NULL; \ + }) + +/** * list_for_each_entry_rcu - iterate over rcu list of given type * @pos: the type * to use as a loop cursor. * @head: the head for your list. |