Re: [f2fs-dev] [PATCH 3/3] f2fs: clean up /sys/fs/f2fs/<disk>/features

[Eric Biggers]

On Fri, Jun 04, 2021 at 05:32:10PM -0700, Jaegeuk Kim wrote:
> +What:		/sys/fs/f2fs/feature/

features/, not feature/.

> +/*
> + * Note that there are three feature list entries:
> + * 1) /sys/fs/f2fs/features
> + *   : shows runtime features supported by in-kernel f2fs along with Kconfig
> + *     - ref. F2FS_FEATURE_RO_ATTR()
> + *
> + * 2) /sys/fs/f2fs/$s_id/features <deprecated>
> + *   : shows on-disk features enabled by mkfs.f2fs, used for old kernels
> + *
> + * 3) /sys/fs/f2fs/$s_id/feature_list
> + *   : shows on-disk features enabled by mkfs.f2fs per instance.
> + *     this list covers old feature list provided by 2) and beyond
> + *     - ref. F2FS_SB_FEATURE_RO_ATTR()
> + */

It would be helpful to make it clear which of these use the one-feature-per-file
convention and which use the comma-separated features convention.  And also
whether future features will be listed in both (2) and (3), or just in (3).

Otherwise this patch looks good -- thanks!

- Eric