[PATCH 4.16 252/279] afs: Fix VNOVOL handling in address rotation

[Greg Kroah-Hartman]

4.16-stable review patch.  If anyone has any objections, please let me know.

------------------

From: David Howells <dhowells@xxxxxxxxxx>

[ Upstream commit 3d9fa91161387ee629e7a07c47934d119910c8ae ]

If a volume location record lists multiple file servers for a volume, then
it's possible that due to a misconfiguration or a changing configuration
that one of the file servers doesn't know about it yet and will abort
VNOVOL.  Currently, the rotation algorithm will stop with EREMOTEIO.

Fix this by moving on to try the next server if VNOVOL is returned.  Once
all the servers have been tried and the record rechecked, the algorithm
will stop with EREMOTEIO or ENOMEDIUM.

Fixes: d2ddc776a458 ("afs: Overhaul volume and server record caching and fileserver rotation")
Reported-by: Marc Dionne <marc.dionne@xxxxxxxxxxxx>
Signed-off-by: David Howells <dhowells@xxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 fs/afs/rotate.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/fs/afs/rotate.c
+++ b/fs/afs/rotate.c
@@ -179,7 +179,7 @@ bool afs_select_fileserver(struct afs_fs
 			 */
 			if (fc->flags & AFS_FS_CURSOR_VNOVOL) {
 				fc->ac.error = -EREMOTEIO;
-				goto failed;
+				goto next_server;
 			}
 
 			write_lock(&vnode->volume->servers_lock);
@@ -201,7 +201,7 @@ bool afs_select_fileserver(struct afs_fs
 			 */
 			if (vnode->volume->servers == fc->server_list) {
 				fc->ac.error = -EREMOTEIO;
-				goto failed;
+				goto next_server;
 			}
 
 			/* Try again */