diff --git a/block/blk-core.c b/block/blk-core.c index f68398cb2ef6..a99b22fac38a 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -327,6 +327,9 @@ EXPORT_SYMBOL_GPL(blk_clear_pm_only); * * Decrements the refcount of the request_queue kobject. When this reaches 0 * we'll have blk_release_queue() called. + * + * Context: Any context, but the last reference must not be dropped from + * atomic context. */ void blk_put_queue(struct request_queue *q) { @@ -359,9 +362,14 @@ EXPORT_SYMBOL_GPL(blk_set_queue_dying); * * Mark @q DYING, drain all pending requests, mark @q DEAD, destroy and * put it. All future requests will be failed immediately with -ENODEV. + * + * Context: can sleep */ void blk_cleanup_queue(struct request_queue *q) { + /* cannot be called from atomic context */ + might_sleep(); + WARN_ON_ONCE(blk_queue_registered(q)); /* mark @q DYING, no new request or merges will be allowed afterwards */ diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c index 02643e149d5e..561624d4cc4e 100644 --- a/block/blk-sysfs.c +++ b/block/blk-sysfs.c @@ -873,22 +873,32 @@ static void blk_exit_queue(struct request_queue *q) bdi_put(q->backing_dev_info); } - /** - * __blk_release_queue - release a request queue - * @work: pointer to the release_work member of the request queue to be released + * blk_release_queue - releases all allocated resources of the request_queue + * @kobj: pointer to a kobject, whose container is a request_queue * - * Description: - * This function is called when a block device is being unregistered. The - * process of releasing a request queue starts with blk_cleanup_queue, which - * set the appropriate flags and then calls blk_put_queue, that decrements - * the reference counter of the request queue. Once the reference counter - * of the request queue reaches zero, blk_release_queue is called to release - * all allocated resources of the request queue. + * This function releases all allocated resources of the request queue. + * + * The struct request_queue refcount is incremented with blk_get_queue() and + * decremented with blk_put_queue(). Once the refcount reaches 0 this function + * is called. + * + * For drivers that have a request_queue on a gendisk and added with + * __device_add_disk() the refcount to request_queue will reach 0 with + * the last put_disk() called by the driver. For drivers which don't use + * __device_add_disk() this happens with blk_cleanup_queue(). + * + * Drivers exist which depend on the release of the request_queue to be + * synchronous, it should not be deferred. + * + * Context: can sleep */ -static void __blk_release_queue(struct work_struct *work) +static void blk_release_queue(struct kobject *kobj) { - struct request_queue *q = container_of(work, typeof(*q), release_work); + struct request_queue *q = + container_of(kobj, struct request_queue, kobj); + + might_sleep(); if (test_bit(QUEUE_FLAG_POLL_STATS, &q->queue_flags)) blk_stat_remove_callback(q, q->poll_cb); @@ -917,15 +927,6 @@ static void __blk_release_queue(struct work_struct *work) call_rcu(&q->rcu_head, blk_free_queue_rcu); } -static void blk_release_queue(struct kobject *kobj) -{ - struct request_queue *q = - container_of(kobj, struct request_queue, kobj); - - INIT_WORK(&q->release_work, __blk_release_queue); - schedule_work(&q->release_work); -} - static const struct sysfs_ops queue_sysfs_ops = { .show = queue_attr_show, .store = queue_attr_store, diff --git a/block/genhd.c b/block/genhd.c index 1be86b1f43ec..60ae4e1b4d38 100644 --- a/block/genhd.c +++ b/block/genhd.c @@ -889,12 +889,19 @@ static void invalidate_partition(struct gendisk *disk, int partno) * The final removal of the struct gendisk happens when its refcount reaches 0 * with put_disk(), which should be called after del_gendisk(), if * __device_add_disk() was used. + * + * Drivers exist which depend on the release of the gendisk to be synchronous, + * it should not be deferred. + * + * Context: can sleep */ void del_gendisk(struct gendisk *disk) { struct disk_part_iter piter; struct hd_struct *part; + might_sleep(); + blk_integrity_del(disk); disk_del_events(disk); @@ -1548,11 +1555,15 @@ int disk_expand_part_tbl(struct gendisk *disk, int partno) * drivers we also call blk_put_queue() for them, and we expect the * request_queue refcount to reach 0 at this point, and so the request_queue * will also be freed prior to the disk. + * + * Context: can sleep */ static void disk_release(struct device *dev) { struct gendisk *disk = dev_to_disk(dev); + might_sleep(); + blk_free_devt(dev->devt); disk_release_events(disk); kfree(disk->random); @@ -1797,6 +1808,9 @@ EXPORT_SYMBOL(get_disk_and_module); * * This decrements the refcount for the struct gendisk. When this reaches 0 * we'll have disk_release() called. + * + * Context: Any context, but the last reference must not be dropped from + * atomic context. */ void put_disk(struct gendisk *disk) { @@ -1811,6 +1825,9 @@ EXPORT_SYMBOL(put_disk); * * This is a counterpart of get_disk_and_module() and thus also of * get_gendisk(). + * + * Context: Any context, but the last reference must not be dropped from + * atomic context. */ void put_disk_and_module(struct gendisk *disk) { diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 98712cfc7a34..e214e0e9f868 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -584,8 +584,6 @@ struct request_queue { size_t cmd_size; - struct work_struct release_work; - #define BLK_MAX_WRITE_HINTS 5 u64 write_hints[BLK_MAX_WRITE_HINTS]; };