Re: [PATCH 2/5] block: merge invalidate_partitions into rescan_partitions

Jan Kara
2019-11-14T13:26:01Z

On Wed 06-11-19 16:14:36, Christoph Hellwig wrote:
> A lot of the logic in invalidate_partitions and invalidate_partitions
^^ rescan_partitions as others already mentioned

> is shared. Merge the two functions to simplify things. There is
> a small behavior change in that we now send the keven change notice
^^^ kevent

> also if we were not invalidating but no partitions were found, which
> seems like the right thing to do.
>
> Signed-off-by: Christoph Hellwig <hch@lst.de>

Otherwise the patch looks good to me. You can add:

Reviewed-by: Jan Kara <jack@suse.cz>

Honza
> ---
> block/ioctl.c | 2 +-
> block/partition-generic.c | 38 ++++++++++++++------------------------
> fs/block_dev.c | 5 +----
> include/linux/genhd.h | 4 ++--
> 4 files changed, 18 insertions(+), 31 deletions(-)
>
> diff --git a/block/ioctl.c b/block/ioctl.c
> index 15a0eb80ada9..8a7e33ce2097 100644
> --- a/block/ioctl.c
> +++ b/block/ioctl.c
> @@ -171,7 +171,7 @@ int __blkdev_reread_part(struct block_device *bdev)
>
> lockdep_assert_held(&bdev->bd_mutex);
>
> - return rescan_partitions(disk, bdev);
> + return rescan_partitions(disk, bdev, false);
> }
> EXPORT_SYMBOL(__blkdev_reread_part);
>
> diff --git a/block/partition-generic.c b/block/partition-generic.c
> index f113be069b40..eae9daa8a523 100644
> --- a/block/partition-generic.c
> +++ b/block/partition-generic.c
> @@ -632,7 +632,8 @@ static int blk_add_partitions(struct gendisk *disk, struct block_device *bdev)
> return ret;
> }
>
> -int rescan_partitions(struct gendisk *disk, struct block_device *bdev)
> +int rescan_partitions(struct gendisk *disk, struct block_device *bdev,
> + bool invalidate)
> {
> int ret;
>
> @@ -641,13 +642,22 @@ int rescan_partitions(struct gendisk *disk, struct block_device *bdev)
> if (ret)
> return ret;
>
> - if (disk->fops->revalidate_disk)
> + if (invalidate)
> + set_capacity(disk, 0);
> + else if (disk->fops->revalidate_disk)
> disk->fops->revalidate_disk(disk);
> - check_disk_size_change(disk, bdev, true);
> +
> + check_disk_size_change(disk, bdev, !invalidate);
> bdev->bd_invalidated = 0;
>
> - if (!get_capacity(disk))
> + if (!get_capacity(disk)) {
> + /*
> + * Tell userspace that the media / partition table may have
> + * changed.
> + */
> + kobject_uevent(&disk_to_dev(disk)->kobj, KOBJ_CHANGE);
> return 0;
> + }
>
> ret = blk_add_partitions(disk, bdev);
> if (ret == -EAGAIN)
> @@ -655,26 +665,6 @@ int rescan_partitions(struct gendisk *disk, struct block_device *bdev)
> return ret;
> }
>
> -int invalidate_partitions(struct gendisk *disk, struct block_device *bdev)
> -{
> - int res;
> -
> - if (!bdev->bd_invalidated)
> - return 0;
> -
> - res = drop_partitions(disk, bdev);
> - if (res)
> - return res;
> -
> - set_capacity(disk, 0);
> - check_disk_size_change(disk, bdev, false);
> - bdev->bd_invalidated = 0;
> - /* tell userspace that the media / partition table may have changed */
> - kobject_uevent(&disk_to_dev(disk)->kobj, KOBJ_CHANGE);
> -
> - return 0;
> -}
> -
> unsigned char *read_dev_sector(struct block_device *bdev, sector_t n, Sector *p)
> {
> struct address_space *mapping = bdev->bd_inode->i_mapping;
> diff --git a/fs/block_dev.c b/fs/block_dev.c
> index d612468ee66b..0af62b76d031 100644
> --- a/fs/block_dev.c
> +++ b/fs/block_dev.c
> @@ -1511,10 +1511,7 @@ static void __blkdev_put(struct block_device *bdev, fmode_t mode, int for_part);
> static void bdev_disk_changed(struct block_device *bdev, bool invalidate)
> {
> if (disk_part_scan_enabled(bdev->bd_disk)) {
> - if (invalidate)
> - invalidate_partitions(bdev->bd_disk, bdev);
> - else
> - rescan_partitions(bdev->bd_disk, bdev);
> + rescan_partitions(bdev->bd_disk, bdev, invalidate);
> } else {
> check_disk_size_change(bdev->bd_disk, bdev, !invalidate);
> bdev->bd_invalidated = 0;
> diff --git a/include/linux/genhd.h b/include/linux/genhd.h
> index 8b5330dd5ac0..fd7774e64f0b 100644
> --- a/include/linux/genhd.h
> +++ b/include/linux/genhd.h
> @@ -622,8 +622,8 @@ extern dev_t blk_lookup_devt(const char *name, int partno);
> extern char *disk_name (struct gendisk *hd, int partno, char *buf);
>
> extern int disk_expand_part_tbl(struct gendisk *disk, int target);
> -extern int rescan_partitions(struct gendisk *disk, struct block_device *bdev);
> -extern int invalidate_partitions(struct gendisk *disk, struct block_device *bdev);
> +int rescan_partitions(struct gendisk *disk, struct block_device *bdev,
> + bool invalidate);
> extern struct hd_struct * __must_check add_partition(struct gendisk *disk,
> int partno, sector_t start,
> sector_t len, int flags,
> --
> 2.20.1
>
--
Jan Kara <jack@suse.com>
SUSE Labs, CR