packet: Add helpers to register/unregister ->prot_hook

Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
David S. Miller 2011-07-04 01:44:29 -07:00
parent f8bae99ee5
commit ce06b03e60

View file

@ -222,6 +222,55 @@ struct packet_skb_cb {
#define PACKET_SKB_CB(__skb) ((struct packet_skb_cb *)((__skb)->cb))
static inline struct packet_sock *pkt_sk(struct sock *sk)
{
return (struct packet_sock *)sk;
}
/* register_prot_hook must be invoked with the po->bind_lock held,
* or from a context in which asynchronous accesses to the packet
* socket is not possible (packet_create()).
*/
static void register_prot_hook(struct sock *sk)
{
struct packet_sock *po = pkt_sk(sk);
if (!po->running) {
dev_add_pack(&po->prot_hook);
sock_hold(sk);
po->running = 1;
}
}
/* {,__}unregister_prot_hook() must be invoked with the po->bind_lock
* held. If the sync parameter is true, we will temporarily drop
* the po->bind_lock and do a synchronize_net to make sure no
* asynchronous packet processing paths still refer to the elements
* of po->prot_hook. If the sync parameter is false, it is the
* callers responsibility to take care of this.
*/
static void __unregister_prot_hook(struct sock *sk, bool sync)
{
struct packet_sock *po = pkt_sk(sk);
po->running = 0;
__dev_remove_pack(&po->prot_hook);
__sock_put(sk);
if (sync) {
spin_unlock(&po->bind_lock);
synchronize_net();
spin_lock(&po->bind_lock);
}
}
static void unregister_prot_hook(struct sock *sk, bool sync)
{
struct packet_sock *po = pkt_sk(sk);
if (po->running)
__unregister_prot_hook(sk, sync);
}
static inline __pure struct page *pgv_to_page(void *addr)
{
if (is_vmalloc_addr(addr))
@ -324,11 +373,6 @@ static inline void packet_increment_head(struct packet_ring_buffer *buff)
buff->head = buff->head != buff->frame_max ? buff->head+1 : 0;
}
static inline struct packet_sock *pkt_sk(struct sock *sk)
{
return (struct packet_sock *)sk;
}
static void packet_sock_destruct(struct sock *sk)
{
skb_queue_purge(&sk->sk_error_queue);
@ -1337,15 +1381,7 @@ static int packet_release(struct socket *sock)
spin_unlock_bh(&net->packet.sklist_lock);
spin_lock(&po->bind_lock);
if (po->running) {
/*
* Remove from protocol table
*/
po->running = 0;
po->num = 0;
__dev_remove_pack(&po->prot_hook);
__sock_put(sk);
}
unregister_prot_hook(sk, false);
if (po->prot_hook.dev) {
dev_put(po->prot_hook.dev);
po->prot_hook.dev = NULL;
@ -1392,15 +1428,7 @@ static int packet_do_bind(struct sock *sk, struct net_device *dev, __be16 protoc
lock_sock(sk);
spin_lock(&po->bind_lock);
if (po->running) {
__sock_put(sk);
po->running = 0;
po->num = 0;
spin_unlock(&po->bind_lock);
dev_remove_pack(&po->prot_hook);
spin_lock(&po->bind_lock);
}
unregister_prot_hook(sk, true);
po->num = protocol;
po->prot_hook.type = protocol;
if (po->prot_hook.dev)
@ -1413,9 +1441,7 @@ static int packet_do_bind(struct sock *sk, struct net_device *dev, __be16 protoc
goto out_unlock;
if (!dev || (dev->flags & IFF_UP)) {
dev_add_pack(&po->prot_hook);
sock_hold(sk);
po->running = 1;
register_prot_hook(sk);
} else {
sk->sk_err = ENETDOWN;
if (!sock_flag(sk, SOCK_DEAD))
@ -1542,9 +1568,7 @@ static int packet_create(struct net *net, struct socket *sock, int protocol,
if (proto) {
po->prot_hook.type = proto;
dev_add_pack(&po->prot_hook);
sock_hold(sk);
po->running = 1;
register_prot_hook(sk);
}
spin_lock_bh(&net->packet.sklist_lock);
@ -2240,9 +2264,7 @@ static int packet_notifier(struct notifier_block *this, unsigned long msg, void
if (dev->ifindex == po->ifindex) {
spin_lock(&po->bind_lock);
if (po->running) {
__dev_remove_pack(&po->prot_hook);
__sock_put(sk);
po->running = 0;
__unregister_prot_hook(sk, false);
sk->sk_err = ENETDOWN;
if (!sock_flag(sk, SOCK_DEAD))
sk->sk_error_report(sk);
@ -2259,11 +2281,8 @@ static int packet_notifier(struct notifier_block *this, unsigned long msg, void
case NETDEV_UP:
if (dev->ifindex == po->ifindex) {
spin_lock(&po->bind_lock);
if (po->num && !po->running) {
dev_add_pack(&po->prot_hook);
sock_hold(sk);
po->running = 1;
}
if (po->num)
register_prot_hook(sk);
spin_unlock(&po->bind_lock);
}
break;
@ -2530,10 +2549,8 @@ static int packet_set_ring(struct sock *sk, struct tpacket_req *req,
was_running = po->running;
num = po->num;
if (was_running) {
__dev_remove_pack(&po->prot_hook);
po->num = 0;
po->running = 0;
__sock_put(sk);
__unregister_prot_hook(sk, false);
}
spin_unlock(&po->bind_lock);
@ -2564,11 +2581,9 @@ static int packet_set_ring(struct sock *sk, struct tpacket_req *req,
mutex_unlock(&po->pg_vec_lock);
spin_lock(&po->bind_lock);
if (was_running && !po->running) {
sock_hold(sk);
po->running = 1;
if (was_running) {
po->num = num;
dev_add_pack(&po->prot_hook);
register_prot_hook(sk);
}
spin_unlock(&po->bind_lock);