Commit af281414 authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Jens Axboe
Browse files

block: freeze the queue in queue_attr_store 



queue_attr_store updates attributes used to control generating I/O, and
can cause malformed bios if changed with I/O in flight.  Freeze the queue
in common code instead of adding it to almost every attribute.

Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarBart Van Assche <bvanassche@acm.org>
Reviewed-by: default avatarDamien Le Moal <dlemoal@kernel.org>
Reviewed-by: default avatarHannes Reinecke <hare@suse.de>
Reviewed-by: default avatarChaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20240617060532.127975-12-hch@lst.de


Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 6b377787

block/blk-mq.c

+3 −2
Original line number Diff line number Diff line
@@ -4631,13 +4631,15 @@ int blk_mq_update_nr_requests(struct request_queue *q, unsigned int nr) 
	int ret;

	unsigned long i;



	if (WARN_ON_ONCE(!q->mq_freeze_depth))

		return -EINVAL;



	if (!set)

		return -EINVAL;



	if (q->nr_requests == nr)

		return 0;



	blk_mq_freeze_queue(q);

	blk_mq_quiesce_queue(q);



	ret = 0;
@@ -4671,7 +4673,6 @@ int blk_mq_update_nr_requests(struct request_queue *q, unsigned int nr) 
	}



	blk_mq_unquiesce_queue(q);

	blk_mq_unfreeze_queue(q);



	return ret;

}

block/blk-sysfs.c

+2 −7
Original line number Diff line number Diff line
@@ -189,12 +189,9 @@ static ssize_t queue_discard_max_store(struct request_queue *q, 
	if ((max_discard_bytes >> SECTOR_SHIFT) > UINT_MAX)

		return -EINVAL;



	blk_mq_freeze_queue(q);

	lim = queue_limits_start_update(q);

	lim.max_user_discard_sectors = max_discard_bytes >> SECTOR_SHIFT;

	err = queue_limits_commit_update(q, &lim);

	blk_mq_unfreeze_queue(q);



	if (err)

		return err;

	return ret;
@@ -241,11 +238,9 @@ queue_max_sectors_store(struct request_queue *q, const char *page, size_t count) 
	if (ret < 0)

		return ret;



	blk_mq_freeze_queue(q);

	lim = queue_limits_start_update(q);

	lim.max_user_sectors = max_sectors_kb << 1;

	err = queue_limits_commit_update(q, &lim);

	blk_mq_unfreeze_queue(q);

	if (err)

		return err;

	return ret;
@@ -585,13 +580,11 @@ static ssize_t queue_wb_lat_store(struct request_queue *q, const char *page, 
	 * ends up either enabling or disabling wbt completely. We can't

	 * have IO inflight if that happens.

	 */

	blk_mq_freeze_queue(q);

	blk_mq_quiesce_queue(q);



	wbt_set_min_lat(q, val);



	blk_mq_unquiesce_queue(q);

	blk_mq_unfreeze_queue(q);



	return count;

}
@@ -722,9 +715,11 @@ queue_attr_store(struct kobject *kobj, struct attribute *attr, 
	if (!entry->store)

		return -EIO;



	blk_mq_freeze_queue(q);

	mutex_lock(&q->sysfs_lock);

	res = entry->store(q, page, length);

	mutex_unlock(&q->sysfs_lock);

	blk_mq_unfreeze_queue(q);

	return res;

}