Re: [RFC PATCH v3 6/8] fuse: implementation of lookup_handle+statx compound operation

[Luis Henriques]

On Thu, Feb 26 2026, Miklos Szeredi wrote:

> On Thu, 26 Feb 2026 at 11:08, Amir Goldstein <amir73il@xxxxxxxxx> wrote:
>
>> file handle on stack only makes sense for small pre allocated size.
>> If the server has full control over handle size, then that is not relevant.
>
> I thought the point was that the file handle is available in
> fi->handle and doesn't need to be allocated/copied.   Instead
> extensions could be done with an argument vector, like this:

Right now the code is using extensions in the lookup_handle operation
inargs, and only if a file handle is available for the parent inode.

Are you saying that outargs should also use extensions for getting the
file handle in a lookup_handle?

Cheers,
-- 
Luís

> --- a/fs/fuse/fuse_i.h
> +++ b/fs/fuse/fuse_i.h
> @@ -326,6 +326,12 @@ struct fuse_folio_desc {
>         unsigned int offset;
>  };
>
> +struct fuse_ext_arg {
> +       u32 type;
> +       u32 size;
> +       const void *value;
> +};
> +
>  struct fuse_args {
>         uint64_t nodeid;
>         uint32_t opcode;
> @@ -346,6 +352,7 @@ struct fuse_args {
>         bool is_pinned:1;
>         bool invalidate_vmap:1;
>         struct fuse_in_arg in_args[4];
> +       struct fuse_ext_arg ext_args[2];
>         struct fuse_arg out_args[2];
>         void (*end)(struct fuse_mount *fm, struct fuse_args *args, int error);
>         /* Used for kvec iter backed by vmalloc address */
>
> Thanks,
> Miklos