Re: [RFC] ext4: Add support for ext4_map_blocks_atomic()

John Garry
2024-03-13T18:41:29Z

On 08/03/2024 20:25, Ritesh Harjani (IBM) wrote:

Hi Ritesh,

> Currently ext4 exposes [fsawu_min, fsawu_max] size as
> [blocksize, clustersize] (given the hw block device constraints are
> larger than FS atomic write units).
>
> That means a user should be allowed to -
> 1. pwrite 0 4k /mnt/test/f1
> 2. pwrite 0 16k /mnt/test/f1
>

Previously you have mentioned 2 or 3 methods in which ext4 could support
atomic writes. To avoid doubt, is this patch for the "Add intelligence
in multi-block allocator of ext4 to provide aligned allocations (this
option won't require any formatting)" method mentioned at
https://lore.kernel.org/linux-fsdevel/8734tb0xx7.fsf@doe.com/

and same as method 3 at
https://lore.kernel.org/linux-fsdevel/cover.1709356594.git.ritesh.list@gmail.com/?

Thanks,
John