From mboxrd@z Thu Jan 1 00:00:00 1970 From: Luca Berra Subject: Re: patches for mdadm 1.8.0 (auto=dev and stacking of devices) Date: Sun, 23 Jan 2005 20:14:15 +0100 Message-ID: <20050123191415.GF15317@percy.comedia.it> References: <20050123151305.GB15317@percy.comedia.it> <20050123152819.GE24350@marowsky-bree.de> <41F3D4E5.1020300@tls.msk.ru> <20050123170009.GD15317@percy.comedia.it> <5d8dc2-utu.ln1@news.it.uc3m.es> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Return-path: Content-Disposition: inline In-Reply-To: <5d8dc2-utu.ln1@news.it.uc3m.es> Sender: linux-raid-owner@vger.kernel.org To: linux-raid@vger.kernel.org List-Id: linux-raid.ids On Sun, Jan 23, 2005 at 07:52:53PM +0100, Peter T. Breuer wrote: >Luca Berra wrote: >> I believe the correct solution to this would be implementing a char-misc >Making special device files "on demand" requires the cooperation of the >driver and devfs (and since udev apparently replaces devfs, udev). One >would need to add the code to the driver. devfs just created 256 /dev/md/ entries, and that was obnoxyous, besides now we have mdp devices, and one of the aims of udev was avoiding /dev pollution with un-needed nodes. >> >BTW, is there a real need to do that? In theory, one might just >> >create the necessary /dev/md1 from within startup script... >> I would have done it in a script if --auto was not implemented, the >> changes to have auto=dev are not big, mostly man page and indenting. > >I'm not sure I follow that. If I understand you, --auto was what you >added to mdadm to make the special device files. nope, --auto was added by Neil some time ago, it is mostly needed for mdp devices, i just added the "dev" option to --auto. >Personally I would prefer there to be no unannounced making of device >files, but yours is an extra flag so it does no harm in that sense. >However, I think it is a mistaken addition. You can see that by asking >yourself why EVERY control utility does not have that option in it. >Hdparm? Fdisk? > >The answer is: because it's (a) silly, (b) none of its business. And >the same applies here. If the sysadmin does not want a dev file, then >let him be. If he wants one, let him make it. you should have told Neil back then. >However, as a matter of convenience, I would prefer that the driver >made the devices in /dev or /sys or wherever if it can. I don't recall >if the code is there or not! yes, but then you would need the char device trick. >Is there a udev document anywhere? I searched in 2.6.8.1 and found >nothing (I won't burden you with the details of my obviously too >cursory search). > ftp://ftp.kernel.org/pub/linux/utils/kernel/hotplug L. -- Luca Berra -- bluca@comedia.it Communication Media & Services S.r.l. /"\ \ / ASCII RIBBON CAMPAIGN X AGAINST HTML MAIL / \