blk-mq: Add a flag for reserved requests
Add a flag for reserved requests so that drivers may know this for any
special handling.
Signed-off-by: John Garry <john.garry@huawei.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/1657109034-206040-3-git-send-email-john.garry@huawei.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
diff --git a/block/blk-mq.c b/block/blk-mq.c
index 15c7c5c..a00e43c 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -475,6 +475,9 @@ static struct request *__blk_mq_alloc_requests(struct blk_mq_alloc_data *data)
if (!(data->rq_flags & RQF_ELV))
blk_mq_tag_busy(data->hctx);
+ if (data->flags & BLK_MQ_REQ_RESERVED)
+ data->rq_flags |= RQF_RESV;
+
/*
* Try batched alloc if we want more than 1 tag.
*/
@@ -589,6 +592,9 @@ struct request *blk_mq_alloc_request_hctx(struct request_queue *q,
else
data.rq_flags |= RQF_ELV;
+ if (flags & BLK_MQ_REQ_RESERVED)
+ data.rq_flags |= RQF_RESV;
+
ret = -EWOULDBLOCK;
tag = blk_mq_get_tag(&data);
if (tag == BLK_MQ_NO_TAG)
