[PATCH 1/3] cifs: do not share tcons with DFS

[Paulo Alcantara]

This disables tcon re-use for DFS shares.

tcon->dfs_path stores the path that the tcon should connect to when
doing failing over.

If that tcon is used multiple times e.g. 2 mounts using it with
different prefixpath, each will need a different dfs_path but there is
only one tcon. The other solution would be to split the tcon in 2
tcons during failover but that is much harder.

Signed-off-by: Paulo Alcantara (SUSE) <pc at cjr.nz>
Reviewed-by: Aurelien Aptel <aaptel at suse.com>
---
 fs/cifs/connect.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index 95b3ab0ca8c0..ac6d286fe79f 100644
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -3373,7 +3373,7 @@ cifs_find_tcon(struct cifs_ses *ses, struct smb_vol *volume_info)
 	spin_lock(&cifs_tcp_ses_lock);
 	list_for_each(tmp, &ses->tcon_list) {
 		tcon = list_entry(tmp, struct cifs_tcon, tcon_list);
-		if (!match_tcon(tcon, volume_info))
+		if (!match_tcon(tcon, volume_info) || tcon->dfs_path)
 			continue;
 		++tcon->tc_count;
 		spin_unlock(&cifs_tcp_ses_lock);
-- 
2.26.0