From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Wed, 14 Nov 2007 13:40:11 +0100 From: Christian Kellermann To: Fans of the OS Plan 9 from Bell Labs <9fans@cse.psu.edu> Subject: Re: [9fans] Glendix? Message-ID: <20071114124011.GC4327@hermes.my.domain> References: <3a4dacba376b00e27e9c1a6b93c77baa@terzarima.net> <3e1162e60711131404l593f4d99i52e50175151c0959@mail.gmail.com> <225fa8e60711131823u7d5b43f0qaad32084eb821d20@mail.gmail.com> <225fa8e60711140417g20915568r70a27f2dab69a247@mail.gmail.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="jCrbxBqMcLqd4mOl" Content-Disposition: inline In-Reply-To: <225fa8e60711140417g20915568r70a27f2dab69a247@mail.gmail.com> User-Agent: Mutt/1.5.16 (2007-06-09) Topicbox-Message-UUID: f90c001a-ead2-11e9-9d60-3106f5b1d025 --jCrbxBqMcLqd4mOl Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable * R <0xef967c36@gmail.com> [071114 13:19]: > On Nov 14, 2007 1:44 PM, Iruata Souza wrote: > > On 11/14/07, R <0xef967c36@gmail.com> wrote: > > > OpenBSD already has filesystems in userland. Look for mount_xfs > > > (nothing to do with the SGI/linux thing). It is used by their afs cli= ent > > > implementation. > > > > > > > if you talking about /sbin/mount_xfs, it's just a mounter for the xfs > > filesystem. if you take a look at /sys/xfs you'll see what have to be > > done in the kernel. >=20 > No, you're wrong ! >=20 > You can write a new filesystem as a userland daemon - and have > it communicate with the kernel via a /dev/xfs* device. > There's no need for extra code in the kernel. >=20 > In fact, that's exactly how afsd (the Andrew Filesystem client, part > of the standard distribution) is working. You are both right. The AFS daemon runs in userspace. There has to be a kernel interface to get it into the systems namespace facility (here it is called VFS). For AFS this interface is very application specifi= c=20 (/dev/xfs) but Iru's approach would allow to write drivers in userspace and communicate with the kernel through an application independent interface. This is what 9p is all about... --=20 You may use my gpg key for replies: pub 1024D/47F79788 2005/02/02 Christian Kellermann (C-Keen) --jCrbxBqMcLqd4mOl Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.7 (OpenBSD) iD8DBQFHOuyrXYob3Uf3l4gRAtJcAJ0aVPAex2DSrEBdzj3Ci2HyWJO5nACgoQ1y +wCflzz72aWv8Wlt8vTrDiQ= =uQWY -----END PGP SIGNATURE----- --jCrbxBqMcLqd4mOl--