From 334335d2f7a077a5ff561d86b0ad43bedd83ca05 Mon Sep 17 00:00:00 2001 From: Omar Sandoval Date: Tue, 28 Mar 2017 16:12:15 -0700 Subject: [PATCH] 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: Omar Sandoval Signed-off-by: Jens Axboe --- block/blk-sysfs.c | 7 +++++++ include/linux/blkdev.h | 1 + 2 files changed, 8 insertions(+) diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c index 7f090dd15ca6..833fb7f9ce9d 100644 --- a/block/blk-sysfs.c +++ b/block/blk-sysfs.c @@ -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); diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 1a7dc42a8918..a2dc6b390d48 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -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) | \