On Thu 18-05-23 06:23:16, Christoph Hellwig wrote:
> Delay dropping the block_devices for partitions in del_gendisk until
> after the call to blk_mark_disk_dead, so that we can implementat
> notification of removed devices in blk_mark_disk_dead.
>
> This requires splitting a lower-level drop_partition helper out of
> delete_partition and using that from del_gendisk, while having a
> common loop for the whole device and partitions that calls
> remove_inode_hash, fsync_bdev and __invalidate_device before the
> call to blk_mark_disk_dead.
>
> Signed-off-by: Christoph Hellwig <hch@xxxxxx>
Looks good. Feel free to add:
Reviewed-by: Jan Kara <jack@xxxxxxx>
Honza
> ---
> block/blk.h | 2 +-
> block/genhd.c | 24 +++++++++++++++++++-----
> block/partitions/core.c | 19 ++++++++++++-------
> 3 files changed, 32 insertions(+), 13 deletions(-)
>
> diff --git a/block/blk.h b/block/blk.h
> index 45547bcf111938..4363052f90416a 100644
> --- a/block/blk.h
> +++ b/block/blk.h
> @@ -409,7 +409,7 @@ int bdev_add_partition(struct gendisk *disk, int partno, sector_t start,
> int bdev_del_partition(struct gendisk *disk, int partno);
> int bdev_resize_partition(struct gendisk *disk, int partno, sector_t start,
> sector_t length);
> -void blk_drop_partitions(struct gendisk *disk);
> +void drop_partition(struct block_device *part);
>
> void bdev_set_nr_sectors(struct block_device *bdev, sector_t sectors);
>
> diff --git a/block/genhd.c b/block/genhd.c
> index a744daeed55318..bd4c4eca31363e 100644
> --- a/block/genhd.c
> +++ b/block/genhd.c
> @@ -615,6 +615,8 @@ EXPORT_SYMBOL_GPL(blk_mark_disk_dead);
> void del_gendisk(struct gendisk *disk)
> {
> struct request_queue *q = disk->queue;
> + struct block_device *part;
> + unsigned long idx;
>
> might_sleep();
>
> @@ -623,16 +625,28 @@ void del_gendisk(struct gendisk *disk)
>
> disk_del_events(disk);
>
> + /*
> + * Prevent new openers by unlinked the bdev inode, and write out
> + * dirty data before marking the disk dead and stopping all I/O.
> + */
> mutex_lock(&disk->open_mutex);
> - remove_inode_hash(disk->part0->bd_inode);
> - blk_drop_partitions(disk);
> + xa_for_each(&disk->part_tbl, idx, part) {
> + remove_inode_hash(part->bd_inode);
> + fsync_bdev(part);
> + __invalidate_device(part, true);
> + }
> mutex_unlock(&disk->open_mutex);
>
> - fsync_bdev(disk->part0);
> - __invalidate_device(disk->part0, true);
> -
> blk_mark_disk_dead(disk);
>
> + /*
> + * Drop all partitions now that the disk is marked dead.
> + */
> + mutex_lock(&disk->open_mutex);
> + xa_for_each_start(&disk->part_tbl, idx, part, 1)
> + drop_partition(part);
> + mutex_unlock(&disk->open_mutex);
> +
> if (!(disk->flags & GENHD_FL_HIDDEN)) {
> sysfs_remove_link(&disk_to_dev(disk)->kobj, "bdi");
>
> diff --git a/block/partitions/core.c b/block/partitions/core.c
> index fa5c707fe0ad2f..31ac815d77a83c 100644
> --- a/block/partitions/core.c
> +++ b/block/partitions/core.c
> @@ -263,10 +263,19 @@ struct device_type part_type = {
> .uevent = part_uevent,
> };
>
> -static void delete_partition(struct block_device *part)
> +void drop_partition(struct block_device *part)
> {
> lockdep_assert_held(&part->bd_disk->open_mutex);
>
> + xa_erase(&part->bd_disk->part_tbl, part->bd_partno);
> + kobject_put(part->bd_holder_dir);
> +
> + device_del(&part->bd_device);
> + put_device(&part->bd_device);
> +}
> +
> +static void delete_partition(struct block_device *part)
> +{
> /*
> * Remove the block device from the inode hash, so that it cannot be
> * looked up any more even when openers still hold references.
> @@ -276,11 +285,7 @@ static void delete_partition(struct block_device *part)
> fsync_bdev(part);
> __invalidate_device(part, true);
>
> - xa_erase(&part->bd_disk->part_tbl, part->bd_partno);
> - kobject_put(part->bd_holder_dir);
> - device_del(&part->bd_device);
> -
> - put_device(&part->bd_device);
> + drop_partition(part);
> }
>
> static ssize_t whole_disk_show(struct device *dev,
> @@ -519,7 +524,7 @@ static bool disk_unlock_native_capacity(struct gendisk *disk)
> return true;
> }
>
> -void blk_drop_partitions(struct gendisk *disk)
> +static void blk_drop_partitions(struct gendisk *disk)
> {
> struct block_device *part;
> unsigned long idx;
> --
> 2.39.2
>
--
Jan Kara <jack@xxxxxxxx>
SUSE Labs, CR
