[PATCH 74/78] block: merge struct block_device and struct hd_struct

[Hannes Reinecke]

On 11/16/20 3:58 PM, Christoph Hellwig wrote:
> Instead of having two structures that represent each block device with
> different lift time rules merged them into a single one.  This also
> greatly simplifies the reference counting rules, as we can use the inode
> reference count as the main reference count for the new struct
> block_device, with the device model reference front ending it for device
> model interaction.  The percpu refcount in struct hd_struct is entirely
> gone given that struct block_device must be opened and thus valid for
> the duration of the I/O.
> 
> Signed-off-by: Christoph Hellwig <hch at lst.de>
> ---
>   block/bio.c                        |   6 +-
>   block/blk-cgroup.c                 |   9 +-
>   block/blk-core.c                   |  85 +++++-----
>   block/blk-flush.c                  |   2 +-
>   block/blk-lib.c                    |   2 +-
>   block/blk-merge.c                  |   6 +-
>   block/blk-mq.c                     |  11 +-
>   block/blk-mq.h                     |   5 +-
>   block/blk.h                        |  38 ++---
>   block/genhd.c                      | 242 +++++++++++------------------
>   block/ioctl.c                      |   4 +-
>   block/partitions/core.c            | 221 +++++++-------------------
>   drivers/block/drbd/drbd_receiver.c |   2 +-
>   drivers/block/drbd/drbd_worker.c   |   2 +-
>   drivers/block/zram/zram_drv.c      |   2 +-
>   drivers/md/bcache/request.c        |   4 +-
>   drivers/md/dm.c                    |   8 +-
>   drivers/md/md.c                    |   4 +-
>   drivers/nvme/target/admin-cmd.c    |  20 +--
>   drivers/s390/block/dasd.c          |   8 +-
>   fs/block_dev.c                     |  68 +++-----
>   fs/ext4/super.c                    |  18 +--
>   fs/ext4/sysfs.c                    |  10 +-
>   fs/f2fs/checkpoint.c               |   5 +-
>   fs/f2fs/f2fs.h                     |   2 +-
>   fs/f2fs/super.c                    |   6 +-
>   fs/f2fs/sysfs.c                    |   9 --
>   include/linux/blk_types.h          |  23 ++-
>   include/linux/blkdev.h             |  13 +-
>   include/linux/genhd.h              |  67 ++------
>   include/linux/part_stat.h          |  17 +-
>   init/do_mounts.c                   |  20 +--
>   kernel/trace/blktrace.c            |  54 ++-----
>   33 files changed, 351 insertions(+), 642 deletions(-)
> 
Reviewed-by: Hannes Reinecke <hare at suse.de>

Cheers,

Hannes
-- 
Dr. Hannes Reinecke                Kernel Storage Architect
hare at suse.de                              +49 911 74053 688
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