Re: [PATCH] statx.2: Document STATX_SUBVOL

[Eric Biggers <ebiggers@kernel.org>]

On Mon, Mar 11, 2024 at 04:31:36PM -0400, Kent Overstreet wrote:
> Document the new statxt.stx_subvol field.
> 
> This would be clearer if we had a proper API for walking subvolumes that
> we could refer to, but that's still coming.
> 
> Link: https://lore.kernel.org/linux-fsdevel/20240308022914.196982-1-kent.overstreet@linux.dev/
> Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
> Cc: Alejandro Colomar <alx@kernel.org>
> Cc: linux-man@vger.kernel.org
> Cc: linux-fsdevel@vger.kernel.org
> ---
>  man2/statx.2 | 8 ++++++++
>  1 file changed, 8 insertions(+)
> 
> diff --git a/man2/statx.2 b/man2/statx.2
> index 0dcf7e20bb1f..480e69b46a89 100644
> --- a/man2/statx.2
> +++ b/man2/statx.2
> @@ -68,6 +68,7 @@ struct statx {
>      /* Direct I/O alignment restrictions */
>      __u32 stx_dio_mem_align;
>      __u32 stx_dio_offset_align;
> +    __u64 stx_subvol;      /* Subvolume identifier */
>  };
>  .EE
>  .in
> @@ -255,6 +256,8 @@ STATX_ALL	The same as STATX_BASIC_STATS | STATX_BTIME.
>  STATX_MNT_ID	Want stx_mnt_id (since Linux 5.8)
>  STATX_DIOALIGN	Want stx_dio_mem_align and stx_dio_offset_align
>  	(since Linux 6.1; support varies by filesystem)
> +STATX_SUBVOL	Wants stx_subvol
> +	(since Linux 6.9; support varies by filesystem)

The other ones say "Want", not "Wants".

> +.TP
> +.I stx_subvolume

It's stx_subvol, not stx_subvolume.

> +Subvolume number of the current file.
> +
> +Subvolumes are fancy directories, i.e. they form a tree structure that may be walked recursively.

How about documenting which filesystems support it?

- Eric