Re: [PATCH] btrfs: add io_uring interface for encoded reads

[David Sterba <dsterba@suse.cz>]

On Mon, Aug 12, 2024 at 05:10:15PM +0100, Pavel Begunkov wrote:
> And the last point, I'm surprised there are two versions of
> btrfs_ioctl_encoded_io_args. Maybe, it's a good moment to fix it if
> we're creating a new interface.
> 
> E.g. by adding a new structure defined right with u64 and such, use it
> in io_uring, and cast to it in the ioctl code when it's x64 (with
> a good set of BUILD_BUG_ON sprinkled) and convert structures otherwise?

If you mean the 32bit version of the ioctl struct
(btrfs_ioctl_encoded_io_args_32), I don't think we can fix it. It's been
there from the beginning and it's not a mistake. I don't remember the
details why and only vaguely remember that I'd asked why we need it.
Similar 64/32 struct is in the send ioctl but that was a mistake due to
a pointer being passed in the structure and that needs to be handled due
to different type width.