From cebbe577cb17ed9b04b50d9e6802a8bacffbadca Mon Sep 17 00:00:00 2001 From: Ming Lei Date: Thu, 14 Jul 2022 18:32:01 +0800 Subject: [PATCH] ublk_drv: fix request queue leak Call blk_cleanup_queue() in release code path for fixing request queue leak. Also for-5.20/block has cleaned up blk_cleanup_queue(), which is basically merged to del_gendisk() if blk_mq_alloc_disk() is used for allocating disk and queue. However, ublk may not add disk in case of starting device failure, then del_gendisk() won't be called when removing ublk device, so blk_mq_exit_queue will not be callsed, and it can be bit hard to deal with this kind of merge conflict. Turns out ublk's queue/disk use model is very similar with scsi, so switch to scsi's model by allocating disk and queue independently, then it can be quite easy to handle v5.20 merge conflict by replacing blk_cleanup_queue with blk_mq_destroy_queue. Reported-by: Jens Axboe Fixes: 71f28f3136af ("ublk_drv: add io_uring based userspace block driver") Signed-off-by: Ming Lei Link: https://lore.kernel.org/r/20220714103201.131648-1-ming.lei@redhat.com Signed-off-by: Jens Axboe --- drivers/block/ublk_drv.c | 21 +++++++++++++++------ 1 file changed, 15 insertions(+), 6 deletions(-) diff --git a/drivers/block/ublk_drv.c b/drivers/block/ublk_drv.c index 35fa06e..f10c431 100644 --- a/drivers/block/ublk_drv.c +++ b/drivers/block/ublk_drv.c @@ -155,6 +155,8 @@ static DEFINE_MUTEX(ublk_ctl_mutex); static struct miscdevice ublk_misc; +static struct lock_class_key ublk_bio_compl_lkclass; + static inline bool ublk_can_use_task_work(const struct ublk_queue *ubq) { if (IS_BUILTIN(CONFIG_BLK_DEV_UBLK) && @@ -634,7 +636,7 @@ static void ublk_commit_rqs(struct blk_mq_hw_ctx *hctx) static int ublk_init_hctx(struct blk_mq_hw_ctx *hctx, void *driver_data, unsigned int hctx_idx) { - struct ublk_device *ub = hctx->queue->queuedata; + struct ublk_device *ub = driver_data; struct ublk_queue *ubq = ublk_get_queue(ub, hctx->queue_num); hctx->driver_data = ubq; @@ -1076,6 +1078,8 @@ static void ublk_cdev_rel(struct device *dev) { struct ublk_device *ub = container_of(dev, struct ublk_device, cdev_dev); + blk_mq_destroy_queue(ub->ub_queue); + put_disk(ub->ub_disk); blk_mq_free_tag_set(&ub->tag_set); @@ -1165,14 +1169,17 @@ static int ublk_add_dev(struct ublk_device *ub) if (err) goto out_deinit_queues; - disk = ub->ub_disk = blk_mq_alloc_disk(&ub->tag_set, ub); + ub->ub_queue = blk_mq_init_queue(&ub->tag_set); + if (IS_ERR(ub->ub_queue)) + goto out_cleanup_tags; + ub->ub_queue->queuedata = ub; + + disk = ub->ub_disk = blk_mq_alloc_disk_for_queue(ub->ub_queue, + &ublk_bio_compl_lkclass); if (IS_ERR(disk)) { err = PTR_ERR(disk); - goto out_cleanup_tags; + goto out_free_request_queue; } - ub->ub_queue = ub->ub_disk->queue; - - ub->ub_queue->queuedata = ub; blk_queue_logical_block_size(ub->ub_queue, bsize); blk_queue_physical_block_size(ub->ub_queue, bsize); @@ -1204,6 +1211,8 @@ static int ublk_add_dev(struct ublk_device *ub) return 0; +out_free_request_queue: + blk_mq_destroy_queue(ub->ub_queue); out_cleanup_tags: blk_mq_free_tag_set(&ub->tag_set); out_deinit_queues: -- 2.7.4