We want it to be possible for target_submit_cmd() to return errors up
to its fabric module callers.  For now just update the prototype to
return an int, and update all callers to handle non-zero return values
as an error.

This is immediately useful for tcm_qla2xxx to fix a long-standing active
I/O session shutdown race, but tcm_fc, usb-gadget, and sbp-target the
fabric maintainers need to check + ACK that handling a target_submit_cmd()
failure due to session shutdown does not introduce regressions

(nab: Respin against for-next after initial NACK + update docbook comment +
      fix double se_cmd init in exception path for usb-gadget)

Cc: Chad Dupuis <chad.dupuis@qlogic.com>
Cc: Arun Easi <arun.easi@qlogic.com>
Cc: Chris Boot <bootc@bootc.net>
Cc: Stefan Richter <stefanr@s5r6.in-berlin.de>
Cc: Mark Rustad <mark.d.rustad@intel.com>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Felipe Balbi <balbi@ti.com>
Cc: Andy Grover <agrover@redhat.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

Cc: Chris Boot <bootc@bootc.net>
Cc: Stefan Richter <stefanr@s5r6.in-berlin.de>
Signed-off-by: Roland Dreier <roland@purestorage.com>

Just call target_execute_cmd directly.  Also, convert loopback, sbp,
usb-gadget to use the newly exported target_execute_cmd().

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

'int login_id' shadows 'static atomic_t login_id'.
Seen as compilation warning on x86-32.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Acked-by: Chris Boot <bootc@bootc.net>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

The FireWire SBP-2 Target is a driver for using an IEEE-1394 connection
as a SCSI transport. This module uses the SCSI Target framework to
expose LUNs to other machines attached to a FireWire bus, in effect
acting as a FireWire hard disk similar to FireWire Target Disk mode
on many Apple computers.

This commit contains the squashed pull from Chris Boot's SBP-2-Target:

      https://github.com/bootc/Linux-SBP-2-Target.git patch-v3

firewire-sbp-target: Add sbp_base.h header
firewire-sbp-target: Add sbp_configfs.c
firewire-sbp-target: Add sbp_fabric.{c,h}
firewire-sbp-target: Add sbp_management_agent.{c,h}
firewire-sbp-target: Add sbp_login.{c,h}
firewire-sbp-target: Add sbp_target_agent.{c,h}
firewire-sbp-target: Add sbp_scsi_cmnd.{c,h}
firewire-sbp-target: Add to target Kconfig and Makefile

Also add bootc's entry to the MAINTAINERS file.  Great work Chris !!

Signed-off-by: Chris Boot <bootc@bootc.net>
Acked-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Cc: Andy Grover <agrover@redhat.com>
Cc: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>