From owner-freebsd-hackers Tue Sep 14 7:49: 7 1999 Delivered-To: freebsd-hackers@freebsd.org Received: from fanf.noc.demon.net (fanf.noc.demon.net [195.11.55.83]) by hub.freebsd.org (Postfix) with ESMTP id 25E55150E8 for ; Tue, 14 Sep 1999 07:49:04 -0700 (PDT) (envelope-from fanf@demon.net) Received: from fanf by fanf.noc.demon.net with local (Exim 3.02 #13) id 11QttA-000E4G-00; Tue, 14 Sep 1999 15:48:56 +0100 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit From: Tony Finch To: Matthew Dillon Cc: Tony Finch , hackers@FreeBSD.ORG Subject: Re: mounting a partition more than once In-Reply-To: <199909140504.WAA27333@apollo.backplane.com> References: <199909132116.OAA25920@apollo.backplane.com> <199909140504.WAA27333@apollo.backplane.com> X-Mailer: VM 6.34 under Emacs 19.34.1 Message-Id: Date: Tue, 14 Sep 1999 15:48:56 +0100 Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG Matthew Dillon wrote: > Tony Finch wrote: > :Matthew Dillon wrote: > :> > :> Also, this may not be the best place to put the code. It make sense > :> to be able to mount a block device multiple times in a read-only > :> fashion, but the code should be in the open for the block device > :> rather then in UFS/FFS, so it can be used with other filesystems > :> and for other purposes. > : > :Yes, it's evident that this is true because I had to hack around > :essentially the same test in both spec_open and ffs_mountfs; removing > :the checks down from ffs_mountfs so it relies on spec_mount to DTRT > :would be neater, I think. > > Yes. I think this is the right track to take. The result will be > more useful to the system and probably a cleaner patch as well. I found some problems with the patch last night (after some suggestions from a colleague). There needs to be some additional checking at the level of the syscall code, I think, to prevent mounting the same partition at the same point more than once -- this causes a "lockmgr: locking against myself" panic when unmounting. I also missed out some checks from the remount code... Tony. -- f.a.n.finch dot@dotat.at fanf@demon.net e pluribus unix To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message