diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c index 0ce64dd73cfe..1c6716f51fff 100644 --- a/block/blk-cgroup.c +++ b/block/blk-cgroup.c @@ -748,6 +748,13 @@ int blkg_conf_open_bdev(struct blkg_conf_ctx *ctx) return -ENODEV; } + mutex_lock(&bdev->bd_queue->rq_qos_mutex); + if (!disk_live(bdev->bd_disk)) { + blkdev_put_no_open(bdev); + mutex_unlock(&bdev->bd_queue->rq_qos_mutex); + return -ENODEV; + } + ctx->body = input; ctx->bdev = bdev; return 0; @@ -892,6 +899,7 @@ EXPORT_SYMBOL_GPL(blkg_conf_prep); */ void blkg_conf_exit(struct blkg_conf_ctx *ctx) __releases(&ctx->bdev->bd_queue->queue_lock) + __releases(&ctx->bdev->bd_queue->rq_qos_mutex) { if (ctx->blkg) { spin_unlock_irq(&bdev_get_queue(ctx->bdev)->queue_lock); @@ -899,6 +907,7 @@ void blkg_conf_exit(struct blkg_conf_ctx *ctx) } if (ctx->bdev) { + mutex_unlock(&ctx->bdev->bd_queue->rq_qos_mutex); blkdev_put_no_open(ctx->bdev); ctx->body = NULL; ctx->bdev = NULL; diff --git a/block/blk-core.c b/block/blk-core.c index 00c74330fa92..2ae22bebeb3e 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -420,6 +420,7 @@ struct request_queue *blk_alloc_queue(int node_id) mutex_init(&q->debugfs_mutex); mutex_init(&q->sysfs_lock); mutex_init(&q->sysfs_dir_lock); + mutex_init(&q->rq_qos_mutex); spin_lock_init(&q->queue_lock); init_waitqueue_head(&q->mq_freeze_wq); diff --git a/block/blk-rq-qos.c b/block/blk-rq-qos.c index d8cc820a365e..167be74df4ee 100644 --- a/block/blk-rq-qos.c +++ b/block/blk-rq-qos.c @@ -288,11 +288,13 @@ void rq_qos_wait(struct rq_wait *rqw, void *private_data, void rq_qos_exit(struct request_queue *q) { + mutex_lock(&q->rq_qos_mutex); while (q->rq_qos) { struct rq_qos *rqos = q->rq_qos; q->rq_qos = rqos->next; rqos->ops->exit(rqos); } + mutex_unlock(&q->rq_qos_mutex); } int rq_qos_add(struct rq_qos *rqos, struct gendisk *disk, enum rq_qos_id id, @@ -300,6 +302,8 @@ int rq_qos_add(struct rq_qos *rqos, struct gendisk *disk, enum rq_qos_id id, { struct request_queue *q = disk->queue; + lockdep_assert_held(&q->rq_qos_mutex); + rqos->disk = disk; rqos->id = id; rqos->ops = ops; @@ -307,18 +311,13 @@ int rq_qos_add(struct rq_qos *rqos, struct gendisk *disk, enum rq_qos_id id, /* * No IO can be in-flight when adding rqos, so freeze queue, which * is fine since we only support rq_qos for blk-mq queue. - * - * Reuse ->queue_lock for protecting against other concurrent - * rq_qos adding/deleting */ blk_mq_freeze_queue(q); - spin_lock_irq(&q->queue_lock); if (rq_qos_id(q, rqos->id)) goto ebusy; rqos->next = q->rq_qos; q->rq_qos = rqos; - spin_unlock_irq(&q->queue_lock); blk_mq_unfreeze_queue(q); @@ -330,7 +329,6 @@ int rq_qos_add(struct rq_qos *rqos, struct gendisk *disk, enum rq_qos_id id, return 0; ebusy: - spin_unlock_irq(&q->queue_lock); blk_mq_unfreeze_queue(q); return -EBUSY; } @@ -340,21 +338,15 @@ void rq_qos_del(struct rq_qos *rqos) struct request_queue *q = rqos->disk->queue; struct rq_qos **cur; - /* - * See comment in rq_qos_add() about freezing queue & using - * ->queue_lock. - */ - blk_mq_freeze_queue(q); + lockdep_assert_held(&q->rq_qos_mutex); - spin_lock_irq(&q->queue_lock); + blk_mq_freeze_queue(q); for (cur = &q->rq_qos; *cur; cur = &(*cur)->next) { if (*cur == rqos) { *cur = rqos->next; break; } } - spin_unlock_irq(&q->queue_lock); - blk_mq_unfreeze_queue(q); mutex_lock(&q->debugfs_mutex); diff --git a/block/blk-wbt.c b/block/blk-wbt.c index e49a48684532..53bf5aa6f9ad 100644 --- a/block/blk-wbt.c +++ b/block/blk-wbt.c @@ -942,7 +942,9 @@ int wbt_init(struct gendisk *disk) /* * Assign rwb and add the stats callback. */ + mutex_lock(&q->rq_qos_mutex); ret = rq_qos_add(&rwb->rqos, disk, RQ_QOS_WBT, &wbt_rqos_ops); + mutex_unlock(&q->rq_qos_mutex); if (ret) goto err_free; diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index fe99948688df..b2ac587e3402 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -392,6 +392,7 @@ struct request_queue { struct blk_queue_stats *stats; struct rq_qos *rq_qos; + struct mutex rq_qos_mutex; const struct blk_mq_ops *mq_ops;