From: Mike Snitzer snitzer@redhat.com
[ Upstream commit 681cc5e8667e8579a2da8fa4090c48a2d73fc3bb ]
It is unnecessary to force request-based DM to call into bio-based dm_submit_bio (via indirect disk->fops->submit_bio) only to have it then call blk_mq_submit_bio().
Fix this by establishing a request-based DM block_device_operations (dm_rq_blk_dops, which doesn't have .submit_bio) and update dm_setup_md_queue() to set md->disk->fops to it for DM_TYPE_REQUEST_BASED.
Remove DM_TYPE_REQUEST_BASED conditional in dm_submit_bio and unexport blk_mq_submit_bio.
Fixes: c62b37d96b6eb ("block: move ->make_request_fn to struct block_device_operations") Signed-off-by: Mike Snitzer snitzer@redhat.com Signed-off-by: Sasha Levin sashal@kernel.org --- block/blk-mq.c | 1 - drivers/md/dm.c | 25 ++++++++++++------------- 2 files changed, 12 insertions(+), 14 deletions(-)
diff --git a/block/blk-mq.c b/block/blk-mq.c index cdced4aca2e81..c27a61029cdd0 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -2264,7 +2264,6 @@ blk_qc_t blk_mq_submit_bio(struct bio *bio) blk_queue_exit(q); return BLK_QC_T_NONE; } -EXPORT_SYMBOL_GPL(blk_mq_submit_bio); /* only for request based dm */
void blk_mq_free_rqs(struct blk_mq_tag_set *set, struct blk_mq_tags *tags, unsigned int hctx_idx) diff --git a/drivers/md/dm.c b/drivers/md/dm.c index b060a28ff1c6d..9b005e144014f 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -1762,18 +1762,6 @@ static blk_qc_t dm_submit_bio(struct bio *bio) int srcu_idx; struct dm_table *map;
- if (dm_get_md_type(md) == DM_TYPE_REQUEST_BASED) { - /* - * We are called with a live reference on q_usage_counter, but - * that one will be released as soon as we return. Grab an - * extra one as blk_mq_submit_bio expects to be able to consume - * a reference (which lives until the request is freed in case a - * request is allocated). - */ - percpu_ref_get(&bio->bi_disk->queue->q_usage_counter); - return blk_mq_submit_bio(bio); - } - map = dm_get_live_table(md, &srcu_idx);
/* if we're suspended, we have to queue this io for later */ @@ -1843,6 +1831,7 @@ static int next_free_minor(int *minor) }
static const struct block_device_operations dm_blk_dops; +static const struct block_device_operations dm_rq_blk_dops; static const struct dax_operations dm_dax_ops;
static void dm_wq_work(struct work_struct *work); @@ -2242,9 +2231,10 @@ int dm_setup_md_queue(struct mapped_device *md, struct dm_table *t)
switch (type) { case DM_TYPE_REQUEST_BASED: + md->disk->fops = &dm_rq_blk_dops; r = dm_mq_init_request_queue(md, t); if (r) { - DMERR("Cannot initialize queue for request-based dm-mq mapped device"); + DMERR("Cannot initialize queue for request-based dm mapped device"); return r; } break; @@ -3227,6 +3217,15 @@ static const struct block_device_operations dm_blk_dops = { .owner = THIS_MODULE };
+static const struct block_device_operations dm_rq_blk_dops = { + .open = dm_blk_open, + .release = dm_blk_close, + .ioctl = dm_blk_ioctl, + .getgeo = dm_blk_getgeo, + .pr_ops = &dm_pr_ops, + .owner = THIS_MODULE +}; + static const struct dax_operations dm_dax_ops = { .direct_access = dm_dax_direct_access, .dax_supported = dm_dax_supported,