Re: [PATCH] expfs: Fix exportfs_can_encode_fh() for EXPORT_FH_FID

[Amir Goldstein <amir73il@gmail.com>]

On Wed, Oct 1, 2025 at 4:52 PM Jan Kara <jack@suse.cz> wrote:
>
> After commit 5402c4d4d200 ("exportfs: require ->fh_to_parent() to encode
> connectable file handles") we will fail to create non-decodable file
> handles for filesystems without export operations. Fix it.
>
> Fixes: 5402c4d4d200 ("exportfs: require ->fh_to_parent() to encode connectable file handles")
> Signed-off-by: Jan Kara <jack@suse.cz>

Reviewed-by: Amir Goldstein <amir73il@gmail.com>

> ---
>  include/linux/exportfs.h | 7 ++++---
>  1 file changed, 4 insertions(+), 3 deletions(-)
>
> diff --git a/include/linux/exportfs.h b/include/linux/exportfs.h
> index cfb0dd1ea49c..b80286a73d0a 100644
> --- a/include/linux/exportfs.h
> +++ b/include/linux/exportfs.h
> @@ -314,9 +314,6 @@ static inline bool exportfs_can_decode_fh(const struct export_operations *nop)
>  static inline bool exportfs_can_encode_fh(const struct export_operations *nop,
>                                           int fh_flags)
>  {
> -       if (!nop)
> -               return false;
> -
>         /*
>          * If a non-decodeable file handle was requested, we only need to make
>          * sure that filesystem did not opt-out of encoding fid.
> @@ -324,6 +321,10 @@ static inline bool exportfs_can_encode_fh(const struct export_operations *nop,
>         if (fh_flags & EXPORT_FH_FID)
>                 return exportfs_can_encode_fid(nop);
>
> +       /* Normal file handles cannot be created without export ops */
> +       if (!nop)
> +               return false;
> +
>         /*
>          * If a connectable file handle was requested, we need to make sure that
>          * filesystem can also decode connected file handles.
> --
> 2.51.0
>