From: Al Viro <viro@zeniv.linux.org.uk>
Date: Fri, 12 Sep 2014 22:21:05 +0000 (-0400)
Subject: gfs2_atomic_open(): skip lookups on hashed dentry
X-Git-Tag: firefly_0821_release~176^2~3067^2~9
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=4d93bc3e81736ce55c79d9cae743bab4f89b4f9c;p=firefly-linux-kernel-4.4.55.git

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>
---

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;