cifs: add a "nosharesock" mount option to force new sockets to server to be created

Some servers set max_vcs to 1 and actually do enforce that limit. Add a
new mount option to work around this behavior that forces a mount
request to open a new socket to the server instead of reusing an
existing one.

I'd prefer to come up with a solution that doesn't require this, so
consider this a debug patch that you can use to determine whether this
is the real problem.

Cc: Jim McDonough <jmcd@samba.org>
Cc: Steve French <smfrench@gmail.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>

1 files changed, 8 insertions, 1 deletions

diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index e3bc39bb9d12..180d9b95fab0 100644
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -85,7 +85,7 @@ enum {
         Opt_acl, Opt_noacl, Opt_locallease,
         Opt_sign, Opt_seal, Opt_noac,
         Opt_fsc, Opt_mfsymlinks,
-        Opt_multiuser, Opt_sloppy,
+        Opt_multiuser, Opt_sloppy, Opt_nosharesock,
 
         /* Mount options which take numeric value */
         Opt_backupuid, Opt_backupgid, Opt_uid,
@@ -165,6 +165,7 @@ static const match_table_t cifs_mount_option_tokens = {
         { Opt_mfsymlinks, "mfsymlinks" },
         { Opt_multiuser, "multiuser" },
         { Opt_sloppy, "sloppy" },
+        { Opt_nosharesock, "nosharesock" },
 
         { Opt_backupuid, "backupuid=%s" },
         { Opt_backupgid, "backupgid=%s" },
@@ -1455,6 +1456,9 @@ cifs_parse_mount_options(const char *mountdata, const char *devname,
                 case Opt_sloppy:
                         sloppy = true;
                         break;
+                case Opt_nosharesock:
+                        vol->nosharesock = true;
+                        break;
 
                 /* Numeric Values */
                 case Opt_backupuid:
@@ -2027,6 +2031,9 @@ static int match_server(struct TCP_Server_Info *server, struct smb_vol *vol)
 {
         struct sockaddr *addr = (struct sockaddr *)&vol->dstaddr;
 
+        if (vol->nosharesock)
+                return 0;
+
         if ((server->vals != vol->vals) || (server->ops != vol->ops))
                 return 0;