block: call submit_bio_checks under q_usage_counter

Ensure all bios check the current values of the queue under freeze
protection, i.e. to make sure the zero capacity set by del_gendisk
is actually seen before dispatching to the driver.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20210929071241.934472-2-hch@lst.de
Tested-by: Yi Zhang <yi.zhang@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block/blk-core.c

@@ -899,11 +899,18 @@ static blk_qc_t __submit_bio(struct bio *bio)
 	struct gendisk *disk = bio->bi_bdev->bd_disk;
 	blk_qc_t ret = BLK_QC_T_NONE;
 
-	if (blk_crypto_bio_prep(&bio)) {
-		if (!disk->fops->submit_bio)
-			return blk_mq_submit_bio(bio);
+	if (unlikely(bio_queue_enter(bio) != 0))
+		return BLK_QC_T_NONE;
+
+	if (!submit_bio_checks(bio) || !blk_crypto_bio_prep(&bio))
+		goto queue_exit;
+	if (disk->fops->submit_bio) {
 		ret = disk->fops->submit_bio(bio);
+		goto queue_exit;
 	}
+	return blk_mq_submit_bio(bio);
+
+queue_exit:
 	blk_queue_exit(disk->queue);
 	return ret;
 }
@@ -941,9 +948,6 @@ static blk_qc_t __submit_bio_noacct(struct bio *bio)
 		struct request_queue *q = bio->bi_bdev->bd_disk->queue;
 		struct bio_list lower, same;
 
-		if (unlikely(bio_queue_enter(bio) != 0))
-			continue;
-
 		/*
 		 * Create a fresh bio_list for all subordinate requests.
 		 */
@@ -979,23 +983,12 @@ static blk_qc_t __submit_bio_noacct(struct bio *bio)
 static blk_qc_t __submit_bio_noacct_mq(struct bio *bio)
 {
 	struct bio_list bio_list[2] = { };
-	blk_qc_t ret = BLK_QC_T_NONE;
+	blk_qc_t ret;
 
 	current->bio_list = bio_list;
 
 	do {
-		struct gendisk *disk = bio->bi_bdev->bd_disk;
-
-		if (unlikely(bio_queue_enter(bio) != 0))
-			continue;
-
-		if (!blk_crypto_bio_prep(&bio)) {
-			blk_queue_exit(disk->queue);
-			ret = BLK_QC_T_NONE;
-			continue;
-		}
-
-		ret = blk_mq_submit_bio(bio);
+		ret = __submit_bio(bio);
 	} while ((bio = bio_list_pop(&bio_list[0])));
 
 	current->bio_list = NULL;
@@ -1013,9 +1006,6 @@ static blk_qc_t __submit_bio_noacct_mq(struct bio *bio)
  */
 blk_qc_t submit_bio_noacct(struct bio *bio)
 {
-	if (!submit_bio_checks(bio))
-		return BLK_QC_T_NONE;
-
 	/*
 	 * We only want one ->submit_bio to be active at a time, else stack
 	 * usage with stacked devices could be a problem.  Use current->bio_list