skd_main: don't use req->special

Add a retries field to the internal request structure instead, which gets
set to zero on the first submission.
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

drivers/block/skd_main.c

@@ -181,6 +181,7 @@ struct skd_request_context {
 	struct fit_completion_entry_v1 completion;
 
 	struct fit_comp_error_info err_info;
+	int retries;
 
 	blk_status_t status;
 };
@@ -495,6 +496,11 @@ static blk_status_t skd_mq_queue_rq(struct blk_mq_hw_ctx *hctx,
 	if (unlikely(skdev->state != SKD_DRVR_STATE_ONLINE))
 		return skd_fail_all(q) ? BLK_STS_IOERR : BLK_STS_RESOURCE;
 
+	if (!(req->rq_flags & RQF_DONTPREP)) {
+		skreq->retries = 0;
+		req->rq_flags |= RQF_DONTPREP;
+	}
+
 	blk_mq_start_request(req);
 
 	WARN_ONCE(tag >= skd_max_queue_depth, "%#x > %#x (nr_requests = %lu)\n",
@@ -1426,7 +1432,7 @@ static void skd_resolve_req_exception(struct skd_device *skdev,
 		break;
 
 	case SKD_CHECK_STATUS_REQUEUE_REQUEST:
-		if ((unsigned long) ++req->special < SKD_MAX_RETRIES) {
+		if (++skreq->retries < SKD_MAX_RETRIES) {
 			skd_log_skreq(skdev, skreq, "retry");
 			blk_mq_requeue_request(req, true);
 			break;