Commit 334335d2 authored by Omar Sandoval's avatar Omar Sandoval Committed by Jens Axboe
Browse files

block: warn if sharing request queue across gendisks 



Now that the remaining drivers have been converted to one request queue
per gendisk, let's warn if a request queue gets registered more than
once. This will catch future drivers which might do it inadvertently or
any old drivers that I may have missed.

Signed-off-by: default avatarOmar Sandoval <osandov@fb.com>
Signed-off-by: default avatarJens Axboe <axboe@fb.com>
parent d3cfb2a0

block/blk-sysfs.c

+7 −0
Original line number Diff line number Diff line
@@ -871,6 +871,11 @@ int blk_register_queue(struct gendisk *disk) 
	if (WARN_ON(!q))

		return -ENXIO;



	WARN_ONCE(test_bit(QUEUE_FLAG_REGISTERED, &q->queue_flags),

		  "%s is registering an already registered queue\n",

		  kobject_name(&dev->kobj));

	queue_flag_set_unlocked(QUEUE_FLAG_REGISTERED, q);



	/*

	 * SCSI probing may synchronously create and destroy a lot of

	 * request_queues for non-existent devices.  Shutting down a fully
@@ -931,6 +936,8 @@ void blk_unregister_queue(struct gendisk *disk) 
	if (WARN_ON(!q))

		return;



	queue_flag_clear_unlocked(QUEUE_FLAG_REGISTERED, q);



	if (q->mq_ops)

		blk_mq_unregister_dev(disk_to_dev(disk), q);

include/linux/blkdev.h

+1 −0
Original line number Diff line number Diff line
@@ -617,6 +617,7 @@ struct request_queue { 
#define QUEUE_FLAG_STATS       27	/* track rq completion times */

#define QUEUE_FLAG_RESTART     28	/* queue needs restart at completion */

#define QUEUE_FLAG_POLL_STATS  29	/* collecting stats for hybrid polling */

#define QUEUE_FLAG_REGISTERED  30	/* queue has been registered to a disk */



#define QUEUE_FLAG_DEFAULT	((1 << QUEUE_FLAG_IO_STAT) |		\

				 (1 << QUEUE_FLAG_STACKABLE)	|	\

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