Add resilienthandles mount parm

Since many servers (Windows clients, and non-clustered servers) do not
support persistent handles but do support resilient handles, allow
the user to specify a mount option "resilienthandles" in order
to get more reliable connections and less chance of data loss
(at least when SMB2.1 or later).  Default resilient handle
timeout (120 seconds to recent Windows server) is used.

Reviewed-by: Pavel Shilovsky <pshilovsky@samba.org>
Signed-off-by: Steve French <steve.french@primarydata.com>
diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
index 81273fe..2b510c5 100644
--- a/fs/cifs/cifsglob.h
+++ b/fs/cifs/cifsglob.h
@@ -496,6 +496,7 @@
 	bool nosharesock:1;
 	bool persistent:1;
 	bool nopersistent:1;
+	bool resilient:1; /* noresilient not required since not fored for CA */
 	unsigned int rsize;
 	unsigned int wsize;
 	bool sockopt_tcp_nodelay:1;
@@ -897,6 +898,7 @@
 	bool broken_posix_open; /* e.g. Samba server versions < 3.3.2, 3.2.9 */
 	bool broken_sparse_sup; /* if server or share does not support sparse */
 	bool need_reconnect:1; /* connection reset, tid now invalid */
+	bool use_resilient:1; /* use resilient instead of durable handles */
 	bool use_persistent:1; /* use persistent instead of durable handles */
 #ifdef CONFIG_CIFS_SMB2
 	bool print:1;		/* set if connection to printer share */