On 18/06/2025 09:37, John Garry wrote:
This value in io_min is used to configure any atomic write limit for the
stacked device. The idea is that the atomic write unit max is a
power-of-2 factor of the stripe size, and the stripe size is available
in io_min.
Using io_min causes issues, as:
a. it may be mutated
b. the check for io_min being set for determining if we are dealing with
a striped device is hard to get right, as reported in [0].
This series now sets chunk_sectors limit to share stripe size.
Any more comments here? It would be good to have the md/raid0 and
md/raid10 changes checked by the md maintainers.
Thanks
[0]
https://lore.kernel.org/linux-block/888f3b1d-7817-4007-b3b3-1a2ea04df...@linux.ibm.com/T/#mecca17129f72811137d3c2f1e477634e77f06781
Based on v6.16-rc2
Differences to RFC:
- sanitize chunk_sectors for atomic write limits
- set chunk_sectors in stripe_io_hints()
John Garry (5):
block: sanitize chunk_sectors for atomic write limits
md/raid0: set chunk_sectors limit
md/raid10: set chunk_sectors limit
dm-stripe: limit chunk_sectors to the stripe size
block: use chunk_sectors when evaluating stacked atomic write limits
block/blk-settings.c | 60 ++++++++++++++++++++++++++----------------
drivers/md/dm-stripe.c | 1 +
drivers/md/raid0.c | 1 +
drivers/md/raid10.c | 1 +
4 files changed, 40 insertions(+), 23 deletions(-)
