vfs: Add open by file handle support
[AV: duplicate of open() guts removed; file_open_root() used instead]
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/exportfs/expfs.c b/fs/exportfs/expfs.c
index cfe5573..b05acb7 100644
--- a/fs/exportfs/expfs.c
+++ b/fs/exportfs/expfs.c
@@ -374,6 +374,8 @@
/*
* Try to get any dentry for the given file handle from the filesystem.
*/
+ if (!nop || !nop->fh_to_dentry)
+ return ERR_PTR(-ESTALE);
result = nop->fh_to_dentry(mnt->mnt_sb, fid, fh_len, fileid_type);
if (!result)
result = ERR_PTR(-ESTALE);