2024-01-30 11:33:58

by Jan Kara

[permalink] [raw]
Subject: Re: [RFC PATCH 4/7] ext2: Use dax_is_supported()

On Mon 29-01-24 16:06:28, Mathieu Desnoyers wrote:
> Use dax_is_supported() to validate whether the architecture has
> virtually aliased caches at mount time.
>
> This is relevant for architectures which require a dynamic check
> to validate whether they have virtually aliased data caches
> (ARCH_HAS_CACHE_ALIASING_DYNAMIC=y).
>
> Fixes: d92576f1167c ("dax: does not work correctly with virtual aliasing caches")
> Signed-off-by: Mathieu Desnoyers <[email protected]>
> Cc: Jan Kara <[email protected]>
> Cc: [email protected]
> Cc: Andrew Morton <[email protected]>
> Cc: Linus Torvalds <[email protected]>
> Cc: [email protected]
> Cc: [email protected]
> Cc: Dan Williams <[email protected]>
> Cc: Vishal Verma <[email protected]>
> Cc: Dave Jiang <[email protected]>
> Cc: Matthew Wilcox <[email protected]>
> Cc: [email protected]
> Cc: [email protected]

Looks good to me (although I share Dave's opinion it would be nice to CC
the whole series to fsdevel - luckily we have lore these days so it is not
that tedious to find the whole series :)). Feel free to add:

Acked-by: Jan Kara <[email protected]>

Honza

> ---
> fs/ext2/super.c | 14 +++++++-------
> 1 file changed, 7 insertions(+), 7 deletions(-)
>
> diff --git a/fs/ext2/super.c b/fs/ext2/super.c
> index 01f9addc8b1f..0398e7a90eb6 100644
> --- a/fs/ext2/super.c
> +++ b/fs/ext2/super.c
> @@ -585,13 +585,13 @@ static int parse_options(char *options, struct super_block *sb,
> set_opt(opts->s_mount_opt, XIP);
> fallthrough;
> case Opt_dax:
> -#ifdef CONFIG_FS_DAX
> - ext2_msg(sb, KERN_WARNING,
> - "DAX enabled. Warning: EXPERIMENTAL, use at your own risk");
> - set_opt(opts->s_mount_opt, DAX);
> -#else
> - ext2_msg(sb, KERN_INFO, "dax option not supported");
> -#endif
> + if (dax_is_supported()) {
> + ext2_msg(sb, KERN_WARNING,
> + "DAX enabled. Warning: EXPERIMENTAL, use at your own risk");
> + set_opt(opts->s_mount_opt, DAX);
> + } else {
> + ext2_msg(sb, KERN_INFO, "dax option not supported");
> + }
> break;
>
> #if defined(CONFIG_QUOTA)
> --
> 2.39.2
>
--
Jan Kara <[email protected]>
SUSE Labs, CR