Commit 72211dbe authored by Trond Myklebust's avatar Trond Myklebust
Browse files

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: default avatarTrond Myklebust <Trond.Myklebust@netapp.com>
parent 68bf05ef

fs/nfs/nfs4_fs.h

+1 −0
Original line number Diff line number Diff line
@@ -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;

fs/nfs/nfs4proc.c

+3 −4
Original line number Diff line number Diff line
@@ -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);

}

fs/nfs/nfs4state.c

+7 −2
Original line number Diff line number Diff line
@@ -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);

}

CRA Git | Maintained and supported by SUSTech CRA and CCSE