tree 4dd2c0b34fb7d2cd063f2dc1da11d490c15e415c
parent c6a80e1ff4106755b8e72a88e767deb7c9d45050
author Paulo Alcantara <pc@cjr.nz> 1595335003 -0300
committer Steve French <stfrench@microsoft.com> 1596409226 -0500

cifs: only update prefix path of DFS links in cifs_tree_connect()

For DFS root mounts that contain a prefix path, do not change them
after failover.

E.g., if the user mounts

	//srvA/root/dir1

and then lost connection to srvA, it will reconnect to

	//srvB/root/dir1

In case of DFS links, which may resolve to different prefix paths
depending on their list of targets, the following must be supported:

	- mount //srvA/root/link/bar
	- connect to //srvA/share
	- set prefix path to "bar"
	- lost connection to srvA
	- reconnect to next target: //srvB/share/foo
	- set new prefix path to "foo/bar"

In cifs_tree_connect(), check the server_type field of the cached DFS
referral to determine whether or not prefix path should be updated.

Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>