diff --git a/block/row-iosched.c b/block/row-iosched.c index b7965c61099d..583e75b9572d 100644 --- a/block/row-iosched.c +++ b/block/row-iosched.c @@ -272,7 +272,39 @@ static void row_add_request(struct request_queue *q, row_log_rowq(rd, rqueue->prio, "added request"); } -/* +/** + * row_reinsert_req() - Reinsert request back to the scheduler + * @q: requests queue + * @rq: request to add + * + * Reinsert the given request back to the queue it was + * dispatched from as if it was never dispatched. + * + * Returns 0 on success, error code otherwise + */ +static int row_reinsert_req(struct request_queue *q, + struct request *rq) +{ + struct row_data *rd = q->elevator->elevator_data; + struct row_queue *rqueue = RQ_ROWQ(rq); + + /* Verify rqueue is legitimate */ + if (rqueue->prio >= ROWQ_MAX_PRIO) { + pr_err("\n\nROW BUG: row_reinsert_req() rqueue->prio = %d\n", + rqueue->prio); + blk_dump_rq_flags(rq, ""); + return -EIO; + } + + list_add(&rq->queuelist, &rqueue->fifo); + rd->nr_reqs[rq_data_dir(rq)]++; + + row_log_rowq(rd, rqueue->prio, "request reinserted"); + + return 0; +} + +/** * row_remove_request() - Remove given request from scheduler * @q: requests queue * @rq: request to remove @@ -656,6 +688,7 @@ static struct elevator_type iosched_row = { .elevator_merge_req_fn = row_merged_requests, .elevator_dispatch_fn = row_dispatch_requests, .elevator_add_req_fn = row_add_request, + .elevator_reinsert_req_fn = row_reinsert_req, .elevator_former_req_fn = elv_rb_former_request, .elevator_latter_req_fn = elv_rb_latter_request, .elevator_set_req_fn = row_set_request,