Re: [PATCH 70/78] block: replace bd_mutex with a per-gendisk mutex

[Hannes Reinecke <hare@xxxxxxx>]

On 11/16/20 3:58 PM, Christoph Hellwig wrote:
> bd_mutex is primarily used for synchronizing the block device open and
> release path, which recurses from partitions to the whole disk device.
> The fact that we have two locks makes life unnecessarily complex due
> to lock order constrains.  Replace the two levels of locking with a
> single mutex in the gendisk structure.
>
> Signed-off-by: Christoph Hellwig <hch@xxxxxx>
> ---
>   block/genhd.c                   |  7 ++--
>   block/ioctl.c                   |  4 +-
>   block/partitions/core.c         | 22 +++++-----
>   drivers/block/loop.c            | 14 +++----
>   drivers/block/xen-blkfront.c    |  8 ++--
>   drivers/block/zram/zram_drv.c   |  4 +-
>   drivers/block/zram/zram_drv.h   |  2 +-
>   drivers/md/md.h                 |  7 +---
>   drivers/s390/block/dasd_genhd.c |  8 ++--
>   drivers/scsi/sd.c               |  4 +-
>   fs/block_dev.c                  | 71 +++++++++++++++++----------------
>   fs/btrfs/volumes.c              |  2 +-
>   fs/super.c                      |  8 ++--
>   include/linux/blk_types.h       |  1 -
>   include/linux/genhd.h           |  1 +
>   15 files changed, 80 insertions(+), 83 deletions(-)
Reviewed-by: Hannes Reinecke <hare@xxxxxxx>

Cheers,

Hannes
--
Dr. Hannes Reinecke                Kernel Storage Architect
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