Re: [PATCH v6 1/9] fs: Create sb_encoding() helper

From: Gabriel Krisman Bertazi
Date: Mon Aug 25 2025 - 05:22:08 EST


André Almeida <andrealmeid@xxxxxxxxxx> writes:

> Filesystems that need to deal with the super block encoding need to use
> a if IS_ENABLED(CONFIG_UNICODE) around it because this struct member is
> not declared otherwise. In order to move this if/endif guards outside of
> the filesytem code and make it simpler, create a new function that
> returns the s_encoding member of struct super_block if Unicode is
> enabled, and return NULL otherwise.
>
> Suggested-by: Amir Goldstein <amir73il@xxxxxxxxx>
> Reviewed-by: Amir Goldstein <amir73il@xxxxxxxxx>
> Signed-off-by: André Almeida <andrealmeid@xxxxxxxxxx>

Reviewed-by: Gabriel Krisman Bertazi <gabriel@xxxxxxxxxx>

> ---
> include/linux/fs.h | 11 ++++++++---
> 1 file changed, 8 insertions(+), 3 deletions(-)
>
> diff --git a/include/linux/fs.h b/include/linux/fs.h
> index e1d4fef5c181d291a7c685e5897b2c018df439ae..a4d353a871b094b562a87ddcffe8336a26c5a3e2 100644
> --- a/include/linux/fs.h
> +++ b/include/linux/fs.h
> @@ -3733,15 +3733,20 @@ static inline bool generic_ci_validate_strict_name(struct inode *dir, struct qst
> }
> #endif
>
> -static inline bool sb_has_encoding(const struct super_block *sb)
> +static inline struct unicode_map *sb_encoding(const struct super_block *sb)
> {
> #if IS_ENABLED(CONFIG_UNICODE)
> - return !!sb->s_encoding;
> + return sb->s_encoding;
> #else
> - return false;
> + return NULL;
> #endif
> }
>
> +static inline bool sb_has_encoding(const struct super_block *sb)
> +{
> + return !!sb_encoding(sb);
> +}
> +
> int may_setattr(struct mnt_idmap *idmap, struct inode *inode,
> unsigned int ia_valid);
> int setattr_prepare(struct mnt_idmap *, struct dentry *, struct iattr *);

--
Gabriel Krisman Bertazi