atm: add owner of push() callback to atmvcc

The atm is using atmvcc->push(vcc, NULL) callback to notify protocol
that vcc will be closed and protocol must detach from it. This callback
is usually used by protocol to decrement module usage count by module_put(),
but it leaves small window then module is still used after module_put().

Now the owner of push() callback is kept in atmvcc and
module_put(atmvcc->owner) is called after the protocol is detached from vcc.

Signed-off-by: Krzysztof Mazur <krzysiek@podlesie.net>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Acked-by: Chas Williams <chas@cmf.nrl.navy.mil>
This commit is contained in:
Krzysztof Mazur 2012-11-06 23:16:57 +01:00 committed by David Woodhouse
parent ae088d663b
commit ec809bd817
2 changed files with 3 additions and 0 deletions

View File

@ -106,6 +106,7 @@ struct atm_vcc {
void *dev_data; /* per-device data */
void *proto_data; /* per-protocol data */
struct k_atm_aal_stats *stats; /* pointer to AAL stats group */
struct module *owner; /* owner of ->push function */
/* SVC part --- may move later ------------------------------------- */
short itf; /* interface number */
struct sockaddr_atmsvc local;

View File

@ -156,6 +156,7 @@ int vcc_create(struct net *net, struct socket *sock, int protocol, int family)
atomic_set(&sk->sk_rmem_alloc, 0);
vcc->push = NULL;
vcc->pop = NULL;
vcc->owner = NULL;
vcc->push_oam = NULL;
vcc->vpi = vcc->vci = 0; /* no VCI/VPI yet */
vcc->atm_options = vcc->aal_options = 0;
@ -175,6 +176,7 @@ static void vcc_destroy_socket(struct sock *sk)
vcc->dev->ops->close(vcc);
if (vcc->push)
vcc->push(vcc, NULL); /* atmarpd has no push */
module_put(vcc->owner);
while ((skb = skb_dequeue(&sk->sk_receive_queue)) != NULL) {
atm_return(vcc, skb->truesize);