From mboxrd@z Thu Jan  1 00:00:00 1970
From: Olaf Buddenhagen <olafbuddenhagen@gmx.net>
Subject: Re: AMD GPU new API for new module
Date: Fri, 10 Oct 2014 04:25:13 +0200
Message-ID: <20141010022509.GA13466@alien.local>
References: <20141008160026.GA7643@gmail.com>
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Hi,

On Wed, Oct 08, 2014 at 12:00:27PM -0400, Jerome Glisse wrote:

[...]
> And now all ioctl go through this single entry point :
>
> int radeon_ioctl_stub(int ioctl, void *data, ...)
> {
> 	struct radeon_ioctl *rio = data;
>
> 	return rdispatch_ioctls[rio->version][ioctl](data, ...);
> }

I advise against this: it's essentially implementing IOCTLs on top of an
IOCTL...

It doesn't really reduce the maintenance burden: just moves it from the
standard IOCTL dispatching to a custom mechanism; while adding extra
complexity, and making the interface more opaque. (Think strace, or
Valgrind.)

-antrik-