Re: [PATCH v4 0/5] RAID 0/1/10 atomic write support

[John Garry <john.g.garry@oracle.com>]

On 12/11/2024 12:42, John Garry wrote:

Hi Song, Kuai,

Can you check the remaining 2x patches in this series when you get a chance?

I was hoping that I could get this queued for 6.13 via the block tree.

Thanks,
John

Ps. I do appreciate that I am pinging on this quite early, but those 
patches mentioned have not changed since the last revision.

> This series introduces atomic write support for software RAID 0/1/10.
> 
> The main changes are to ensure that we can calculate the stacked device
> request_queue limits appropriately for atomic writes. Fundamentally, if
> some bottom does not support atomic writes, then atomic writes are not
> supported for the top device. Furthermore, the atomic writes limits are
> the lowest common supported limits from all bottom devices.
> 
> Flag BLK_FEAT_ATOMIC_WRITES_STACKED is introduced to enable atomic writes
> for stacked devices selectively. This ensures that we can analyze and test
> atomic writes support per individual md/dm personality (prior to
> enabling).
> 
> Based on 0b4ace9da58d (for-6.13/block) nvme-multipath: don't bother
> clearing max_hw_zone_append_sectors
> 
> Differences to v3:
> - Add RB tags from Christoph and Kuai (thanks!)
> - Rebase
> 
> Differences to v2:
> - Refactor blk_stack_atomic_writes_limits() (Christoph)
> - Relocate RAID 1/10 BB check (Kuai)
> - Add RB tag from Christoph (Thanks!)
> - Set REQ_ATOMIC for RAID 1/10
> 
> John Garry (5):
>    block: Add extra checks in blk_validate_atomic_write_limits()
>    block: Support atomic writes limits for stacked devices
>    md/raid0: Atomic write support
>    md/raid1: Atomic write support
>    md/raid10: Atomic write support
> 
>   block/blk-settings.c   | 132 +++++++++++++++++++++++++++++++++++++++++
>   drivers/md/raid0.c     |   1 +
>   drivers/md/raid1.c     |  14 ++++-
>   drivers/md/raid10.c    |  14 ++++-
>   include/linux/blkdev.h |   4 ++
>   5 files changed, 161 insertions(+), 4 deletions(-)
>