From owner-freebsd-current@FreeBSD.ORG Sun Jan 30 15:14:34 2005 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 4192316A4CE; Sun, 30 Jan 2005 15:14:34 +0000 (GMT) Received: from mailout08.sul.t-online.com (mailout08.sul.t-online.com [194.25.134.20]) by mx1.FreeBSD.org (Postfix) with ESMTP id 678C343D41; Sun, 30 Jan 2005 15:14:33 +0000 (GMT) (envelope-from Alexander@Leidinger.net) Received: from fwd06.aul.t-online.de by mailout08.sul.t-online.com with smtp id 1CvGlT-0007Mr-00; Sun, 30 Jan 2005 16:13:27 +0100 Received: from Andro-Beta.Leidinger.net (TEvtdgZHQeCXSAp+zf-kyt2LkASTtrq9YETWfuKY7Z--woZ8X8+oZA@[217.83.23.129]) by fmrl06.sul.t-online.com with esmtp id 1CvGlN-1naHSa0; Sun, 30 Jan 2005 16:13:21 +0100 Received: from Magellan.Leidinger.net (Magellan.Leidinger.net [192.168.1.1]) j0UFD3Sh069567; Sun, 30 Jan 2005 16:13:04 +0100 (CET) (envelope-from Alexander@Leidinger.net) Date: Sun, 30 Jan 2005 16:13:23 +0100 From: Alexander Leidinger To: Robert Watson Message-ID: <20050130161323.5e25414e@Magellan.Leidinger.net> In-Reply-To: References: <20050125.095019.71141844.imp@harmony.village.org> X-Mailer: Sylpheed-Claws 1.0.0 (GTK+ 1.2.10; i386-portbld-freebsd6.0) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-ID: TEvtdgZHQeCXSAp+zf-kyt2LkASTtrq9YETWfuKY7Z--woZ8X8+oZA@t-dialin.net X-TOI-MSGID: c3f53cbd-9563-4a7c-9f20-76fa9d22f035 cc: Warner Losh cc: current@freebsd.org cc: pete@altadena.net cc: imp@bsdimp.com Subject: Re: Devd event from GEOM? X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 30 Jan 2005 15:14:34 -0000 On Tue, 25 Jan 2005 17:01:27 +0000 (GMT) Robert Watson wrote: > A simple auto-mounter simply watches for every storage device that arrives > via GEOM, checks to see if it's leaf class, and if it is, tastes for a > file system header, auto-detecting some of the simple and common types, > such as FAT, UFS, UFS2, cd9660. It can then use whatever logic it > pleases, probably partly from a config file, to decide where to mount it, > what security parameters to use, etc. Here-in lies the key: because devd > says "a storage device, /dev/ad0s1a arrived", it knows it can just go > ahead and taste, not worrying about rewinding the tape, reading from > kernel memory, etc. The auto-mounter specifically wants to hear only > about GEOMs. While you are talking about it and tossing out ideas... do you also think about what to do when the hardware in question is supposed to go away? Let's take a CD for example, when it arrives the auto-mounter mounts it. Fine, but the CD is locked then. What do we do when we want to remove the CD? Or another example, an USB stick. The hardware isn't locked, but when we just remove it, we're calling for a kernel panic. So we can't talk about a "simple" auto-mounter (device appears -> mount it). And as long as we don't talk about a "not-so-simple" auto-mounter (one which knows about how to interact with non-root users -- perhaps in a safe manner, whatever this means ATM) we don't need to talk about such arrival events, since we need user interaction to remove the devices anyway (when you need to umount the device by hand, it's not that much more effort to mount it in the first place). Bye, Alexander. -- Reboot America. http://www.Leidinger.net Alexander @ Leidinger.net GPG fingerprint = C518 BC70 E67F 143F BE91 3365 79E2 9C60 B006 3FE7