Subject: Re: netbsd32_mount: one possible solution
To: Jason Thorpe <thorpej@shagadelic.org>
From: Quentin Garnier <cube@cubidou.net>
List: tech-kern
Date: 07/23/2005 18:39:10
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On Sat, Jul 23, 2005 at 09:28:40AM -0700, Jason Thorpe wrote:
>=20
> On Jul 22, 2005, at 4:15 PM, Quentin Garnier wrote:
>=20
> >I might not be understanding the idea correctly, but I don't think the
> ><fs>_args structure can be mapped into an uio in a reasonable way.
>=20
> No different than passing a flat buffer, except you can tag it as =20
> SYSSPACE or USERSPACE.

Yes, so it's about the same as passing a flag for the same purpose.

> >The most evil fs I could find so far is umap.  struct umap_args =20
> >contains
> >two pointers to arrays of u_long couples.
>=20
> I would actually love to get rid of the stupid binary argument stuff =20
> for mount, and go with a strings-based approach.

Well, hum, sure.

> >Packing it up into a uio would mean sys_mount itself has to know about
> >how umapfs store they mount data, which kind of defeat the ability
> >for sys_mount to simply call VFS_MOUNT() for the mounted device and be
> >done with it.
>=20
> How is that any different than "translating it and then passing =20
> MNT_KERNSPACE" (or whatever)?

In the COMPAT_NETBSD32 case, it's not.  In the native case, it is.
That's why I precised "sys_mount" and not "netbsd32_mount".

--=20
Quentin Garnier - cube@cubidou.net - cube@NetBSD.org
"When I find the controls, I'll go where I like, I'll know where I want
to be, but maybe for now I'll stay right here on a silent sea."
KT Tunstall, Silent Sea, Eye to the Telescope, 2004.

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