Introduce a function that submits bio to a request-based device driver. The function doesn't offload requests to current->bio_list. It is expected to be called from device mapper, where current->bio_list is already set up. Signed-off-by: Mikulas Patocka <mpatocka@xxxxxxxxxx> --- block/blk-core.c | 16 ++++++++++++++++ include/linux/blkdev.h | 1 + 2 files changed, 17 insertions(+) Index: linux-2.6/block/blk-core.c =================================================================== --- linux-2.6.orig/block/blk-core.c 2021-03-01 19:47:27.000000000 +0100 +++ linux-2.6/block/blk-core.c 2021-03-02 10:43:28.000000000 +0100 @@ -992,6 +992,22 @@ static blk_qc_t __submit_bio_noacct(stru return ret; } +blk_qc_t submit_bio_noacct_mq_direct(struct bio *bio) +{ + struct gendisk *disk = bio->bi_bdev->bd_disk; + + if (unlikely(bio_queue_enter(bio) != 0)) + return BLK_QC_T_NONE; + + if (!blk_crypto_bio_prep(&bio)) { + blk_queue_exit(disk->queue); + return BLK_QC_T_NONE; + } + + return blk_mq_submit_bio(bio); +} +EXPORT_SYMBOL(submit_bio_noacct_mq_direct); + static blk_qc_t __submit_bio_noacct_mq(struct bio *bio) { struct bio_list bio_list[2] = { }; Index: linux-2.6/include/linux/blkdev.h =================================================================== --- linux-2.6.orig/include/linux/blkdev.h 2021-03-01 19:47:29.000000000 +0100 +++ linux-2.6/include/linux/blkdev.h 2021-03-02 10:44:04.000000000 +0100 @@ -912,6 +912,7 @@ static inline void rq_flush_dcache_pages extern int blk_register_queue(struct gendisk *disk); extern void blk_unregister_queue(struct gendisk *disk); +blk_qc_t submit_bio_noacct_mq_direct(struct bio *bio); blk_qc_t submit_bio_noacct(struct bio *bio); extern void blk_rq_init(struct request_queue *q, struct request *rq); extern void blk_put_request(struct request *);