From: Christoph Hellwig hch@lst.de
[ Upstream commit 958148a6ac061a9a80a184ea678a5fa872d0c56f ]
Otherwise feature reconfiguration can race with I/O submission.
Also drop the bio_clear_polled in the error path, as the flag does not matter for instant error completions, it is a left over from when we allowed polled I/O to proceed unpolled in this case.
Signed-off-by: Christoph Hellwig hch@lst.de Reviewed-by: Ming Lei ming.lei@redhat.com Reviewed-by: Nilay Shroff nilay@linux.ibm.com Reviewed-by: Martin K. Petersen martin.petersen@oracle.com Link: https://lore.kernel.org/r/20250110054726.1499538-4-hch@lst.de Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Sasha Levin sashal@kernel.org --- block/blk-core.c | 22 ++++++++++++---------- block/blk-mq.c | 12 ++++++++++-- 2 files changed, 22 insertions(+), 12 deletions(-)
diff --git a/block/blk-core.c b/block/blk-core.c index 666efe8fa2020..6309b3f5a89dc 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -629,8 +629,14 @@ static void __submit_bio(struct bio *bio) blk_mq_submit_bio(bio); } else if (likely(bio_queue_enter(bio) == 0)) { struct gendisk *disk = bio->bi_bdev->bd_disk; - - disk->fops->submit_bio(bio); + + if ((bio->bi_opf & REQ_POLLED) && + !(disk->queue->limits.features & BLK_FEAT_POLL)) { + bio->bi_status = BLK_STS_NOTSUPP; + bio_endio(bio); + } else { + disk->fops->submit_bio(bio); + } blk_queue_exit(disk->queue); }
@@ -805,12 +811,6 @@ void submit_bio_noacct(struct bio *bio) } }
- if (!(q->limits.features & BLK_FEAT_POLL) && - (bio->bi_opf & REQ_POLLED)) { - bio_clear_polled(bio); - goto not_supported; - } - switch (bio_op(bio)) { case REQ_OP_READ: break; @@ -935,7 +935,7 @@ int bio_poll(struct bio *bio, struct io_comp_batch *iob, unsigned int flags) return 0;
q = bdev_get_queue(bdev); - if (cookie == BLK_QC_T_NONE || !(q->limits.features & BLK_FEAT_POLL)) + if (cookie == BLK_QC_T_NONE) return 0;
blk_flush_plug(current->plug, false); @@ -951,7 +951,9 @@ int bio_poll(struct bio *bio, struct io_comp_batch *iob, unsigned int flags) */ if (!percpu_ref_tryget(&q->q_usage_counter)) return 0; - if (queue_is_mq(q)) { + if (!(q->limits.features & BLK_FEAT_POLL)) { + ret = 0; + } else if (queue_is_mq(q)) { ret = blk_mq_poll(q, cookie, iob, flags); } else { struct gendisk *disk = q->disk; diff --git a/block/blk-mq.c b/block/blk-mq.c index 8ac19d4ae3c0a..0137a995b9f37 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -3092,14 +3092,22 @@ void blk_mq_submit_bio(struct bio *bio) }
/* - * Device reconfiguration may change logical block size, so alignment - * check has to be done with queue usage counter held + * Device reconfiguration may change logical block size or reduce the + * number of poll queues, so the checks for alignment and poll support + * have to be done with queue usage counter held. */ if (unlikely(bio_unaligned(bio, q))) { bio_io_error(bio); goto queue_exit; }
+ if ((bio->bi_opf & REQ_POLLED) && + !(q->limits.features & BLK_FEAT_POLL)) { + bio->bi_status = BLK_STS_NOTSUPP; + bio_endio(bio); + goto queue_exit; + } + bio = __bio_split_to_limits(bio, &q->limits, &nr_segs); if (!bio) goto queue_exit;