[SCSI] hpsa: fix handling of protocol error

If a command status of CMD_PROTOCOL_ERR is received, this
information should be conveyed to the SCSI mid layer, not
dropped on the floor.  CMD_PROTOCOL_ERR may be received
from the Smart Array for any commands destined for an external
RAID controller such as a P2000, or commands destined for tape
drives or CD/DVD-ROM drives, if for instance a cable is
disconnected.  This mostly affects multipath configurations, as
disconnecting a cable on a non-multipath configuration is not
going to do anything good regardless of whether CMD_PROTOCOL_ERR
is handled correctly or not.  Not handling CMD_PROTOCOL_ERR
correctly in a multipath configaration involving external RAID
controllers may cause data corruption, so this is quite a serious
bug.  This bug should not normally cause a problem for direct
attached disk storage.

Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com>
Cc: stable@vger.kernel.org
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

drivers/scsi/hpsa.c

@@ -1315,6 +1315,7 @@ static void complete_scsi_command(struct CommandList *cp)
 	}
 		break;
 	case CMD_PROTOCOL_ERR:
+		cmd->result = DID_ERROR << 16;
 		dev_warn(&h->pdev->dev, "cp %p has "
 			"protocol error\n", cp);
 		break;