gfs2_atomic_open(): skip lookups on hashed dentry

hashed dentry can be passed to ->atomic_open() only if
a) it has just passed revalidation and
b) it's negative

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

1 files changed, 5 insertions, 0 deletions

diff --git a/fs/gfs2/inode.c b/fs/gfs2/inode.c
index fc8ac2ee0667..8108b4f0354c 100644
--- a/fs/gfs2/inode.c
+++ b/fs/gfs2/inode.c
@@ -1244,6 +1244,9 @@ static int gfs2_atomic_open(struct inode *dir, struct dentry *dentry,
         struct dentry *d;
         bool excl = !!(flags & O_EXCL);
 
+        if (!d_unhashed(dentry))
+                goto skip_lookup;
+
         d = __gfs2_lookup(dir, dentry, file, opened);
         if (IS_ERR(d))
                 return PTR_ERR(d);
@@ -1260,6 +1263,8 @@ static int gfs2_atomic_open(struct inode *dir, struct dentry *dentry,
         }
 
         BUG_ON(d != NULL);
+
+skip_lookup:
         if (!(flags & O_CREAT))
                 return -ENOENT;