exportfs: Return the minimum required handle size

The exportfs encode handle function should return the minimum required
handle size. This helps user to find out the handle size by passing 0
handle size in the first step and then redoing to the call again with
the returned handle size value.

Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

1 files changed, 6 insertions, 1 deletions

diff --git a/fs/udf/namei.c b/fs/udf/namei.c
index b7c338d5e9d..f1dce848ef9 100644
--- a/fs/udf/namei.c
+++ b/fs/udf/namei.c
@@ -1286,8 +1286,13 @@ static int udf_encode_fh(struct dentry *de, __u32 *fh, int *lenp,
         struct fid *fid = (struct fid *)fh;
         int type = FILEID_UDF_WITHOUT_PARENT;
 
-        if (len < 3 || (connectable && len < 5))
+        if (connectable && (len < 5)) {
+                *lenp = 5;
+                return 255;
+        } else if (len < 3) {
+                *lenp = 3;
                 return 255;
+        }
 
         *lenp = 3;
         fid->udf.block = location.logicalBlockNum;