[PATCH v2] nfs: local_lock: handle async processing of F_SETLK with FL_SLEEP

[Vasily Averin]

nfsd and lockd use F_SETLK cmd with the FL_SLEEP flag set to request
asynchronous processing of blocking locks.

Currently nfs mounted with 'local_lock' option use locks_lock_file_wait()
function blocked on such requests.

To handle such requests properly, non-blocking posix_file_lock()
function should be used instead.

https://bugzilla.kernel.org/show_bug.cgi?id=215383
Signed-off-by: Vasily Averin <vvs@xxxxxxxxxxxxx>
---
v2: fixed 'fl_flags && FL_SLEEP' => 'fl_flags & FL_SLEEP'
---
 fs/nfs/file.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/fs/nfs/file.c b/fs/nfs/file.c
index 24e7dccce355..38e1821cff5d 100644
--- a/fs/nfs/file.c
+++ b/fs/nfs/file.c
@@ -769,9 +769,11 @@ do_setlk(struct file *filp, int cmd, struct file_lock *fl, int is_local)
 	 */
 	if (!is_local)
 		status = NFS_PROTO(inode)->lock(filp, cmd, fl);
+	else if ((fl->fl_flags & FL_SLEEP) && IS_SETLK(cmd))
+		status = posix_lock_file(filp, fl, NULL);
 	else
 		status = locks_lock_file_wait(filp, fl);
-	if (status < 0)
+	if (status)
 		goto out;
 
 	/*
-- 
2.25.1