X-Git-Url: http://review.tizen.org/git/?a=blobdiff_plain;f=fs%2Fgfs2%2Finode.c;h=4e63fbb63151c495e37043fd373f50f2057d01f6;hb=refs%2Fheads%2Faccepted%2Ftizen_unified_toolchain;hp=0eac0450790471d09b49741fbffad643ba74db85;hpb=2a5a4326e58339a26cd1510259e7310b8c0980ff;p=platform%2Fkernel%2Flinux-rpi.git

diff --git a/fs/gfs2/inode.c b/fs/gfs2/inode.c
index 0eac045..4e63fbb 100644
--- a/fs/gfs2/inode.c
+++ b/fs/gfs2/inode.c
@@ -1866,16 +1866,24 @@ out:
 int gfs2_permission(struct mnt_idmap *idmap, struct inode *inode,
 		    int mask)
 {
+	int may_not_block = mask & MAY_NOT_BLOCK;
 	struct gfs2_inode *ip;
 	struct gfs2_holder i_gh;
+	struct gfs2_glock *gl;
 	int error;
 
 	gfs2_holder_mark_uninitialized(&i_gh);
 	ip = GFS2_I(inode);
-	if (gfs2_glock_is_locked_by_me(ip->i_gl) == NULL) {
-		if (mask & MAY_NOT_BLOCK)
+	gl = rcu_dereference_check(ip->i_gl, !may_not_block);
+	if (unlikely(!gl)) {
+		/* inode is getting torn down, must be RCU mode */
+		WARN_ON_ONCE(!may_not_block);
+		return -ECHILD;
+        }
+	if (gfs2_glock_is_locked_by_me(gl) == NULL) {
+		if (may_not_block)
 			return -ECHILD;
-		error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY, &i_gh);
+		error = gfs2_glock_nq_init(gl, LM_ST_SHARED, LM_FLAG_ANY, &i_gh);
 		if (error)
 			return error;
 	}