From owner-freebsd-arch Thu May 17 0:28:23 2001 Delivered-To: freebsd-arch@freebsd.org Received: from superconductor.rush.net (superconductor.rush.net [208.9.155.8]) by hub.freebsd.org (Postfix) with ESMTP id 35B3637B424 for ; Thu, 17 May 2001 00:28:21 -0700 (PDT) (envelope-from bright@superconductor.rush.net) Received: (from bright@localhost) by superconductor.rush.net (8.11.2/8.11.2) id f4H7S6J12802; Thu, 17 May 2001 03:28:06 -0400 (EDT) Date: Thu, 17 May 2001 03:28:06 -0400 From: Alfred Perlstein To: Matt Dillon Cc: Tor.Egge@fast.no, arch@FreeBSD.ORG Subject: Re: Preliminary O_DIRECT patch (for review only, not yet tested!) Message-ID: <20010517032806.N12365@superconductor.rush.net> References: <200105162222.f4GMMpC81247@earth.backplane.com> <200105162331.BAA04708@midten.fast.no> <200105170647.f4H6lkk88458@earth.backplane.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Mailer: Mutt 1.0us In-Reply-To: <200105170647.f4H6lkk88458@earth.backplane.com>; from dillon@earth.backplane.com on Wed, May 16, 2001 at 11:47:46PM -0700 X-all-your-base: are belong to us. Sender: owner-freebsd-arch@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG * Matt Dillon [010517 02:49] wrote: > > I've looked at the rawread/rawwrite issue and I believe it may be > possible to use the already-existing B_VMIO flag coupled with > some VM magic to achieve the equivalent in the buffer cache itself > rather then having to write a rawread/rawwrite function for each > filesystem. Filesystems already support B_VMIO. If it is possible, > then we'll have a general raw I/O solution. I'm not sure what the rawread/rawwrite functions do (I'll review them if/when I get a chance) however if what they do is avoid remapping things into kernel memory it'd be really nice to see them go into the system. Avoiding vm tricks if possible would be nice. -Alfred To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-arch" in the body of the message