qla2xxx: cleanup cmd in qla workqueue before processing TMR

Since cmds go into qla_tgt_wq and TMRs don't, it's possible that TMR
like TASK_ABORT can be queued over the cmd for which it was meant.
To avoid this race, use a per-port list to keep track of cmds that
are enqueued to qla_tgt_wq but not yet processed. When a TMR arrives,
iterate through this list and remove any cmds that match the TMR.
This patch supports TASK_ABORT and LUN_RESET.

Cc: <stable@vger.kernel.org> # v3.18+
Signed-off-by: Swapnil Nagle <swapnil.nagle@purestorage.com>
Signed-off-by: Alexei Potashnik <alexei@purestorage.com>
Acked-by: Quinn Tran <quinn.tran@qlogic.com>
Signed-off-by: Himanshu Madhani <himanshu.madhani@qlogic.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
diff --git a/drivers/scsi/qla2xxx/qla_def.h b/drivers/scsi/qla2xxx/qla_def.h
index 787f901..d9c4ed2 100644
--- a/drivers/scsi/qla2xxx/qla_def.h
+++ b/drivers/scsi/qla2xxx/qla_def.h
@@ -3579,6 +3579,11 @@
 	uint16_t	fcoe_fcf_idx;
 	uint8_t		fcoe_vn_port_mac[6];
 
+	/* list of commands waiting on workqueue */
+	struct list_head	qla_cmd_list;
+	struct list_head	qla_sess_op_cmd_list;
+	spinlock_t		cmd_list_lock;
+
 	uint32_t	vp_abort_cnt;
 
 	struct fc_vport	*fc_vport;	/* holds fc_vport * for each vport */