NFSv4: Release the sequence id before restarting a CLOSE rpc call

If the CLOSE or OPEN_DOWNGRADE call triggers a state recovery, and has
to be resent, then we must release the seqid. Otherwise the open
recovery will wait for the close to finish, which causes a deadlock.

This is mainly a NFSv4.1 problem, although it can theoretically happen
with NFSv4.0 too, in a OPEN_DOWNGRADE situation.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
This commit is contained in:
Trond Myklebust 2009-12-15 14:47:36 -05:00
parent 68bf05efb7
commit 72211dbe72
3 changed files with 11 additions and 6 deletions

View file

@ -286,6 +286,7 @@ extern struct nfs_seqid *nfs_alloc_seqid(struct nfs_seqid_counter *counter);
extern int nfs_wait_on_sequence(struct nfs_seqid *seqid, struct rpc_task *task);
extern void nfs_increment_open_seqid(int status, struct nfs_seqid *seqid);
extern void nfs_increment_lock_seqid(int status, struct nfs_seqid *seqid);
extern void nfs_release_seqid(struct nfs_seqid *seqid);
extern void nfs_free_seqid(struct nfs_seqid *seqid);
extern const nfs4_stateid zero_stateid;

View file

@ -1835,11 +1835,10 @@ static void nfs4_close_done(struct rpc_task *task, void *data)
if (calldata->arg.fmode == 0)
break;
default:
if (nfs4_async_handle_error(task, server, state) == -EAGAIN) {
nfs_restart_rpc(task, server->nfs_client);
return;
}
if (nfs4_async_handle_error(task, server, state) == -EAGAIN)
rpc_restart_call_prepare(task);
}
nfs_release_seqid(calldata->arg.seqid);
nfs_refresh_inode(calldata->inode, calldata->res.fattr);
}

View file

@ -765,16 +765,21 @@ struct nfs_seqid *nfs_alloc_seqid(struct nfs_seqid_counter *counter)
return new;
}
void nfs_free_seqid(struct nfs_seqid *seqid)
void nfs_release_seqid(struct nfs_seqid *seqid)
{
if (!list_empty(&seqid->list)) {
struct rpc_sequence *sequence = seqid->sequence->sequence;
spin_lock(&sequence->lock);
list_del(&seqid->list);
list_del_init(&seqid->list);
spin_unlock(&sequence->lock);
rpc_wake_up(&sequence->wait);
}
}
void nfs_free_seqid(struct nfs_seqid *seqid)
{
nfs_release_seqid(seqid);
kfree(seqid);
}