From mboxrd@z Thu Jan 1 00:00:00 1970 From: Matt Mackall Date: Fri, 09 Jan 2004 01:16:35 +0000 Subject: Re: removable media revalidation - udev vs. devfs or static /dev Message-Id: <20040109011635.GM18208@waste.org> List-Id: References: <200401012333.04930.arvidjaar@mail.ru> <20040103055847.GC5306@kroah.com> <20040108031357.A1396@pclin040.win.tue.nl> <20040108034906.A1409@pclin040.win.tue.nl> <20040108043506.A1555@pclin040.win.tue.nl> <1073608126.1228.16.camel@localhost> In-Reply-To: <1073608126.1228.16.camel@localhost> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Robert Love Cc: Linus Torvalds , Andries Brouwer , Greg KH , Andrey Borzenkov , linux-hotplug-devel@lists.sourceforge.net, linux-kernel@vger.kernel.org On Thu, Jan 08, 2004 at 07:28:47PM -0500, Robert Love wrote: > On Wed, 2004-01-07 at 22:43, Linus Torvalds wrote: > > > Yes. We _could_ do that, by just making a "we noticed the disk change" be > > a hotplug event. However, I'm loath to do that, because some devices > > literally don't even have an easily read disk change signal, so what they > > do is > > I like the idea of a hotplug event on media change (basically, a hotplug > event for partitions). And, in fact, I am loath not to do it. > > The current direction with the kernel and udev is letting us move _away_ > from polling. Projects such as HAL are helping to finally integrate > hardware management throughout the system. But HAL is going to be very > confused by some of the alternative solutions for partitions: requiring > that all of the partition device nodes preexist is going to really > complicate things, and I really do not want to have to poll on all of > them in order for HAL to have an idea of what partitions are valid. > > But I hear you loud and clear about dumb devices that cannot detect > media change. They pose a problem. If we have a hotplug media change event we can do: if new device x appears: x->device_nodes = all possible partition nodes start_media_change_timer() if media change on x: x->device_nodes = current media partitions clear_media_change_timer() create_nodes(x) if timeout: /* we didn't get media change so create all nodes */ create_nodes(x) Then the dumb devices (which should be a small minority) just show up with a harmless excess of partitions. -- Matt Mackall : http://www.selenic.com : Linux development and consulting ------------------------------------------------------- This SF.net email is sponsored by: Perforce Software. Perforce is the Fast Software Configuration Management System offering advanced branching capabilities and atomic changes on 50+ platforms. Free Eval! http://www.perforce.com/perforce/loadprog.html _______________________________________________ Linux-hotplug-devel mailing list http://linux-hotplug.sourceforge.net Linux-hotplug-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/linux-hotplug-devel