Commit 1221b9e9 authored by Ming Lei's avatar Ming Lei Committed by Jens Axboe
Browse files

ublk: improve getting & putting ublk device 



Firstly convert get_device() and put_device() into ublk_get_device()
and ublk_put_device().

Secondly annotate ublk_get_device() & ublk_put_device() as noinline
for trace, especially it is often to trigger device deletion hang
when incorrect order is used on ublkc mmap, ublkc close,
io_uring_sqe_unregister_file, ublkb close.

Signed-off-by: default avatarMing Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20240223075539.89945-2-ming.lei@redhat.com


Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent ec30b461

drivers/block/ublk_drv.c

+7 −5
Original line number Diff line number Diff line
@@ -605,14 +605,16 @@ static inline bool ublk_need_get_data(const struct ublk_queue *ubq) 
	return ubq->flags & UBLK_F_NEED_GET_DATA;

}



static struct ublk_device *ublk_get_device(struct ublk_device *ub)

/* Called in slow path only, keep it noinline for trace purpose */

static noinline struct ublk_device *ublk_get_device(struct ublk_device *ub)

{

	if (kobject_get_unless_zero(&ub->cdev_dev.kobj))

		return ub;

	return NULL;

}



static void ublk_put_device(struct ublk_device *ub)

/* Called in slow path only, keep it noinline for trace purpose */

static noinline void ublk_put_device(struct ublk_device *ub)

{

	put_device(&ub->cdev_dev);

}
@@ -671,7 +673,7 @@ static void ublk_free_disk(struct gendisk *disk) 
	struct ublk_device *ub = disk->private_data;



	clear_bit(UB_STATE_USED, &ub->state);

	put_device(&ub->cdev_dev);

	ublk_put_device(ub);

}



static void ublk_store_owner_uid_gid(unsigned int *owner_uid,
@@ -2142,7 +2144,7 @@ static void ublk_remove(struct ublk_device *ub) 
	cancel_work_sync(&ub->stop_work);

	cancel_work_sync(&ub->quiesce_work);

	cdev_device_del(&ub->cdev, &ub->cdev_dev);

	put_device(&ub->cdev_dev);

	ublk_put_device(ub);

	ublks_added--;

}
@@ -2235,7 +2237,7 @@ static int ublk_ctrl_start_dev(struct ublk_device *ub, struct io_uring_cmd *cmd) 
	if (ub->nr_privileged_daemon != ub->nr_queues_ready)

		set_bit(GD_SUPPRESS_PART_SCAN, &disk->state);



	get_device(&ub->cdev_dev);

	ublk_get_device(ub);

	ub->dev_info.state = UBLK_S_DEV_LIVE;



	if (ublk_dev_is_zoned(ub)) {