Re: [PATCH 3/5] block: move rescan_partitions to fs/block_dev.c

Hannes Reinecke
2019-11-07T09:48:55Z

On 11/6/19 4:14 PM, Christoph Hellwig wrote:
> Large parts of rescan_partitions aren't about partitions, and
> moving it to block_dev.c will allow for some further cleanups by
> merging it into its only caller.
>
> Signed-off-by: Christoph Hellwig <hch@lst.de>
> ---
> block/partition-generic.c | 37 ++-----------------------------------
> fs/block_dev.c | 38 ++++++++++++++++++++++++++++++++++++--
> include/linux/fs.h | 2 --
> include/linux/genhd.h | 4 ++--
> 4 files changed, 40 insertions(+), 41 deletions(-)
>
> diff --git a/block/partition-generic.c b/block/partition-generic.c
> index eae9daa8a523..7a6e406ac490 100644
> --- a/block/partition-generic.c
> +++ b/block/partition-generic.c
> @@ -439,7 +439,7 @@ static bool disk_unlock_native_capacity(struct gendisk *disk)
> }
> }
>
> -static int drop_partitions(struct gendisk *disk, struct block_device *bdev)
> +int blk_drop_partitions(struct gendisk *disk, struct block_device *bdev)
> {
> struct disk_part_iter piter;
> struct hd_struct *part;
> @@ -573,7 +573,7 @@ static bool blk_add_partition(struct gendisk *disk, struct block_device *bdev,
> return true;
> }
>
> -static int blk_add_partitions(struct gendisk *disk, struct block_device *bdev)
> +int blk_add_partitions(struct gendisk *disk, struct block_device *bdev)
> {
> struct parsed_partitions *state;
> int ret = -EAGAIN, p, highest;
> @@ -632,39 +632,6 @@ static int blk_add_partitions(struct gendisk *disk, struct block_device *bdev)
> return ret;
> }
>
> -int rescan_partitions(struct gendisk *disk, struct block_device *bdev,
> - bool invalidate)
> -{
> - int ret;
> -
> -rescan:
> - ret = drop_partitions(disk, bdev);
> - if (ret)
> - return ret;
> -
> - if (invalidate)
> - set_capacity(disk, 0);
> - else if (disk->fops->revalidate_disk)
> - disk->fops->revalidate_disk(disk);
> -
> - check_disk_size_change(disk, bdev, !invalidate);
> - bdev->bd_invalidated = 0;
> -
> - 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)
> - goto rescan;
> - return ret;
> -}
> -
> 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 0af62b76d031..f0710085e1f1 100644
> --- a/fs/block_dev.c
> +++ b/fs/block_dev.c
> @@ -1416,8 +1416,8 @@ static void flush_disk(struct block_device *bdev, bool kill_dirty)
> * and adjusts it if it differs. When shrinking the bdev size, its all caches
> * are freed.
> */
> -void check_disk_size_change(struct gendisk *disk, struct block_device *bdev,
> - bool verbose)
> +static void check_disk_size_change(struct gendisk *disk,
> + struct block_device *bdev, bool verbose)
> {
> loff_t disk_size, bdev_size;
>
> @@ -1508,6 +1508,40 @@ EXPORT_SYMBOL(bd_set_size);
>
> static void __blkdev_put(struct block_device *bdev, fmode_t mode, int for_part);
>
> +static int rescan_partitions(struct gendisk *disk, struct block_device *bdev,
> + bool invalidate)
> +{
> + int ret;
> +
> +rescan:
> + ret = blk_drop_partitions(disk, bdev);
> + if (ret)
> + return ret;
> +
> + if (invalidate)
> + set_capacity(disk, 0);
> + else if (disk->fops->revalidate_disk)
> + disk->fops->revalidate_disk(disk);
> +
> + check_disk_size_change(disk, bdev, !invalidate);
> + bdev->bd_invalidated = 0;
> +
> + 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)
> + goto rescan;
> + return ret;
> +}
> +
> +
> static void bdev_disk_changed(struct block_device *bdev, bool invalidate)
> {
> if (disk_part_scan_enabled(bdev->bd_disk)) {

... see my comments in the previous patch to drop get_capacity() and
have check_disk_size_change() return bool ...

Cheers,

Hannes
--
Dr. Hannes Reinecke Teamlead Storage & Networking
hare@suse.de +49 911 74053 688
SUSE Software Solutions Germany GmbH, Maxfeldstr. 5, 90409 Nürnberg
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