Commit 4d637168 authored Jun 12, 2014 by Christoph Hellwig

fnic: reject device resets without assigned tags for the blk-mq case



Current the midlayer fakes up a struct request for the explicit reset
ioctls, and those don't have a tag allocated to them.  The fnic driver pokes
into midlayer structures to paper over this design issue, but that won't
work for the blk-mq case.

Either someone who can actually test the hardware will have to come up with
a similar hack for the blk-mq case, or we'll have to bite the bullet and fix
the way the EH ioctls work for real, but until that happens we fail these
explicit requests here.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Webb Scales <webbnh@hp.com>
Acked-by: Jens Axboe <axboe@kernel.dk>
Tested-by: Bart Van Assche <bvanassche@acm.org>
Tested-by: Robert Elliott <elliott@hp.com>
Cc: Hiral Patel <hiralpat@cisco.com>
Cc: Suma Ramars <sramars@cisco.com>
Cc: Brian Uchino <buchino@cisco.com>

parent d285203c

drivers/scsi/fnic/fnic_scsi.c

+16 −0

Original line number	Diff line number	Diff line
		@@ -2224,6 +2224,22 @@ int fnic_device_reset(struct scsi_cmnd *sc)

		tag = sc->request->tag;
		if (unlikely(tag < 0)) {
		/*
		* XXX(hch): current the midlayer fakes up a struct
		* request for the explicit reset ioctls, and those
		* don't have a tag allocated to them. The below
		* code pokes into midlayer structures to paper over
		* this design issue, but that won't work for blk-mq.
		*
		* Either someone who can actually test the hardware
		* will have to come up with a similar hack for the
		* blk-mq case, or we'll have to bite the bullet and
		* fix the way the EH ioctls work for real, but until
		* that happens we fail these explicit requests here.
		*/
		if (shost_use_blk_mq(sc->device->host))
		goto fnic_device_reset_end;

		tag = fnic_scsi_host_start_tag(fnic, sc);
		if (unlikely(tag == SCSI_NO_TAG))
		goto fnic_device_reset_end;