2 files changed, 39 insertions, 31 deletions

diff --git a/fs/lockd/clntlock.c b/fs/lockd/clntlock.c
index 464cb15c1a06..c374ee072db3 100644
--- a/fs/lockd/clntlock.c
+++ b/fs/lockd/clntlock.c
@@ -82,41 +82,42 @@ void nlmclnt_done(struct nlm_host *host)
 }
 EXPORT_SYMBOL_GPL(nlmclnt_done);
 
+void nlmclnt_prepare_block(struct nlm_wait *block, struct nlm_host *host, struct file_lock *fl)
+{
+	block->b_host = host;
+	block->b_lock = fl;
+	init_waitqueue_head(&block->b_wait);
+	block->b_status = nlm_lck_blocked;
+}
+
 /*
  * Queue up a lock for blocking so that the GRANTED request can see it
  */
-struct nlm_wait *nlmclnt_prepare_block(struct nlm_host *host, struct file_lock *fl)
+void nlmclnt_queue_block(struct nlm_wait *block)
 {
-	struct nlm_wait *block;
-
-	block = kmalloc(sizeof(*block), GFP_KERNEL);
-	if (block != NULL) {
-		block->b_host = host;
-		block->b_lock = fl;
-		init_waitqueue_head(&block->b_wait);
-		block->b_status = nlm_lck_blocked;
-
-		spin_lock(&nlm_blocked_lock);
-		list_add(&block->b_list, &nlm_blocked);
-		spin_unlock(&nlm_blocked_lock);
-	}
-	return block;
+	spin_lock(&nlm_blocked_lock);
+	list_add(&block->b_list, &nlm_blocked);
+	spin_unlock(&nlm_blocked_lock);
 }
 
-void nlmclnt_finish_block(struct nlm_wait *block)
+/*
+ * Dequeue the block and return its final status
+ */
+__be32 nlmclnt_dequeue_block(struct nlm_wait *block)
 {
-	if (block == NULL)
-		return;
+	__be32 status;
+
 	spin_lock(&nlm_blocked_lock);
 	list_del(&block->b_list);
+	status = block->b_status;
 	spin_unlock(&nlm_blocked_lock);
-	kfree(block);
+	return status;
 }
 
 /*
  * Block on a lock
  */
-int nlmclnt_block(struct nlm_wait *block, struct nlm_rqst *req, long timeout)
+int nlmclnt_wait(struct nlm_wait *block, struct nlm_rqst *req, long timeout)
 {
 	long ret;
 
@@ -142,7 +143,6 @@ int nlmclnt_block(struct nlm_wait *block, struct nlm_rqst *req, long timeout)
 	/* Reset the lock status after a server reboot so we resend */
 	if (block->b_status == nlm_lck_denied_grace_period)
 		block->b_status = nlm_lck_blocked;
-	req->a_res.status = block->b_status;
 	return 0;
 }
 
diff --git a/fs/lockd/clntproc.c b/fs/lockd/clntproc.c
index 16b4de868cd2..a14c9110719c 100644
--- a/fs/lockd/clntproc.c
+++ b/fs/lockd/clntproc.c
@@ -516,9 +516,10 @@ nlmclnt_lock(struct nlm_rqst *req, struct file_lock *fl)
 	const struct cred *cred = nfs_file_cred(fl->fl_file);
 	struct nlm_host	*host = req->a_host;
 	struct nlm_res	*resp = &req->a_res;
-	struct nlm_wait *block = NULL;
+	struct nlm_wait block;
 	unsigned char fl_flags = fl->fl_flags;
 	unsigned char fl_type;
+	__be32 b_status;
 	int status = -ENOLCK;
 
 	if (nsm_monitor(host) < 0)
@@ -531,31 +532,41 @@ nlmclnt_lock(struct nlm_rqst *req, struct file_lock *fl)
 	if (status < 0)
 		goto out;
 
-	block = nlmclnt_prepare_block(host, fl);
+	nlmclnt_prepare_block(&block, host, fl);
 again:
 	/*
 	 * Initialise resp->status to a valid non-zero value,
 	 * since 0 == nlm_lck_granted
 	 */
 	resp->status = nlm_lck_blocked;
-	for(;;) {
+
+	/*
+	 * A GRANTED callback can come at any time -- even before the reply
+	 * to the LOCK request arrives, so we queue the wait before
+	 * requesting the lock.
+	 */
+	nlmclnt_queue_block(&block);
+	for (;;) {
 		/* Reboot protection */
 		fl->fl_u.nfs_fl.state = host->h_state;
 		status = nlmclnt_call(cred, req, NLMPROC_LOCK);
 		if (status < 0)
 			break;
 		/* Did a reclaimer thread notify us of a server reboot? */
-		if (resp->status ==  nlm_lck_denied_grace_period)
+		if (resp->status == nlm_lck_denied_grace_period)
 			continue;
 		if (resp->status != nlm_lck_blocked)
 			break;
 		/* Wait on an NLM blocking lock */
-		status = nlmclnt_block(block, req, NLMCLNT_POLL_TIMEOUT);
+		status = nlmclnt_wait(&block, req, NLMCLNT_POLL_TIMEOUT);
 		if (status < 0)
 			break;
-		if (resp->status != nlm_lck_blocked)
+		if (block.b_status != nlm_lck_blocked)
 			break;
 	}
+	b_status = nlmclnt_dequeue_block(&block);
+	if (resp->status == nlm_lck_blocked)
+		resp->status = b_status;
 
 	/* if we were interrupted while blocking, then cancel the lock request
 	 * and exit
@@ -564,7 +575,7 @@ again:
 		if (!req->a_args.block)
 			goto out_unlock;
 		if (nlmclnt_cancel(host, req->a_args.block, fl) == 0)
-			goto out_unblock;
+			goto out;
 	}
 
 	if (resp->status == nlm_granted) {
@@ -593,8 +604,6 @@ again:
 		status = -ENOLCK;
 	else
 		status = nlm_stat_to_errno(resp->status);
-out_unblock:
-	nlmclnt_finish_block(block);
 out:
 	nlmclnt_release_call(req);
 	return status;
@@ -602,7 +611,6 @@ out_unlock:
 	/* Fatal error: ensure that we remove the lock altogether */
 	dprintk("lockd: lock attempt ended in fatal error.\n"
 		"       Attempting to unlock.\n");
-	nlmclnt_finish_block(block);
 	fl_type = fl->fl_type;
 	fl->fl_type = F_UNLCK;
 	down_read(&host->h_rwsem);