smb: client: fast fail sends if need to reconnect

smb_send_kvec() keeps retrying when server needs to reconnect, which
makes no sense as cifs_reconnect() will never run in parallel (because
both need server mutex).
IOW, retrying will never succeed, but only delay reconnects further.

Bail out early from smb_send_kvec() when need to reconnect.

Also shutdown socket queues when CifsNeedReconnect is first detected,
so any sends/receives fails immediately (and don't wait for socket to
timeout).

Add TCP_Server_Info::need_sock_shutdown to ensure socket is shutdown
only once -- even though socket/TCP API will prevent multiple shutdowns,
we need to prevent, from cifs side, concurrent tasks from accidentally
shutting down the socket again in case cifs_reconnect() is successful.

kernel_sock_shutdown() will be called from whichever task detects it
first;  cifsd (cifs_tcp_ses_needs_reconnect()), or sending tasks,
through cifs_call_async() or compound_send_recv().

Signed-off-by: Enzo Matsumiya <ematsumiya@suse.de>
Reviewed-by: David Howells <dhowells@redhat.com>
Signed-off-by: Paulo Alcantara <pc@manguebit.org>

0 files changed, 0 insertions, 0 deletions