firewire: Only free ORBs that completed the initial transaction.

In some situations we can receive the ORB status write before we
have received the ORB pointer write response.  When this happens,
we assume that the fw_transaction is finished and free the ORB
struct containing the fw_transaction.

This fix make the status write logic only accept status writes
for ORBs where the initial ORB pointer write transaction finished.
Signed-off-by: Kristian Høgsberg <krh@redhat.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>

drivers/firewire/fw-sbp2.c

@@ -293,7 +293,8 @@ sbp2_status_write(struct fw_card *card, struct fw_request *request,
 	spin_lock_irqsave(&card->lock, flags);
 	list_for_each_entry(orb, &sd->orb_list, link) {
 		if (status_get_orb_high(status) == 0 &&
-		    status_get_orb_low(status) == orb->request_bus) {
+		    status_get_orb_low(status) == orb->request_bus &&
+		    orb->rcode == RCODE_COMPLETE) {
 			list_del(&orb->link);
 			break;
 		}
@@ -968,6 +969,8 @@ static int sbp2_scsi_queuecommand(struct scsi_cmnd *cmd, scsi_done_fn_t done)
 		goto fail_alloc;
 	}
 
+	/* Initialize rcode to something not RCODE_COMPLETE. */
+	orb->base.rcode = -1;
 	orb->base.request_bus =
 		dma_map_single(device->card->device, &orb->request,
 			       sizeof orb->request, DMA_TO_DEVICE);