diff options
| author | Christoph Hellwig <hch@lst.de> | 2020-04-14 09:42:24 +0200 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2020-04-22 10:47:35 -0600 |
| commit | cc97923a5bccc776851c242b61015faf288d5c22 (patch) | |
| tree | d6510d4f326674e96bdf70c4f07472f492537db8 /block/blk-mq.c | |
| parent | 0475bd6c65976c390e3805a1e5f10fc30ca8def2 (diff) | |
block: move dma drain handling to scsi
Don't burden the common block code with with specifics of the libata DMA
draining mechanism. Instead move most of the code to the scsi midlayer.
That also means the nr_phys_segments adjustments in the blk-mq fast path
can go away entirely, given that SCSI never looks at nr_phys_segments
after mapping the request to a scatterlist.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'block/blk-mq.c')
| -rw-r--r-- | block/blk-mq.c | 11 |
1 files changed, 0 insertions, 11 deletions
diff --git a/block/blk-mq.c b/block/blk-mq.c index cf95e8e0881a..2c105cb2a75b 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -667,15 +667,6 @@ void blk_mq_start_request(struct request *rq) blk_add_timer(rq); WRITE_ONCE(rq->state, MQ_RQ_IN_FLIGHT); - if (q->dma_drain_size && blk_rq_bytes(rq)) { - /* - * Make sure space for the drain appears. We know we can do - * this because max_hw_segments has been adjusted to be one - * fewer than the device can handle. - */ - rq->nr_phys_segments++; - } - #ifdef CONFIG_BLK_DEV_INTEGRITY if (blk_integrity_rq(rq) && req_op(rq) == REQ_OP_WRITE) q->integrity.profile->prepare_fn(rq); @@ -695,8 +686,6 @@ static void __blk_mq_requeue_request(struct request *rq) if (blk_mq_request_started(rq)) { WRITE_ONCE(rq->state, MQ_RQ_IDLE); rq->rq_flags &= ~RQF_TIMED_OUT; - if (q->dma_drain_size && blk_rq_bytes(rq)) - rq->nr_phys_segments--; } } |