Commit b4a6bb3a authored Nov 02, 2022 by Christoph Hellwig Committed by Damien Le Moal Jan 14, 2023

block: add a sanity check for non-write flush/fua bios



Check that the PREFUSH and FUA flags are only set on write bios,
given that the flush state machine expects that.

[Damien] The check is also extended to REQ_OP_ZONE_APPEND operations as
these are data write operations used by btrfs and zonefs and may also
have the REQ_FUA bit set.

Reported-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Reviewed-by: Niklas Cassel <niklas.cassel@wdc.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>

parent 002c4871

block/blk-core.c

+9 −5

Original line number	Diff line number	Diff line
		@@ -744,14 +744,18 @@ void submit_bio_noacct(struct bio *bio)
		* Filter flush bio's early so that bio based drivers without flush
		* support don't have to worry about them.
		*/
		if (op_is_flush(bio->bi_opf) &&
		!test_bit(QUEUE_FLAG_WC, &q->queue_flags)) {
		if (op_is_flush(bio->bi_opf)) {
		if (WARN_ON_ONCE(bio_op(bio) != REQ_OP_WRITE &&
		bio_op(bio) != REQ_OP_ZONE_APPEND))
		goto end_io;
		if (!test_bit(QUEUE_FLAG_WC, &q->queue_flags)) {
		bio->bi_opf &= ~(REQ_PREFLUSH \| REQ_FUA);
		if (!bio_sectors(bio)) {
		status = BLK_STS_OK;
		goto end_io;
		}
		}
		}

		if (!test_bit(QUEUE_FLAG_POLL, &q->queue_flags))
		bio_clear_polled(bio);