From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jan Kara Subject: Re: ext3/4, btrfs, ocfs2: How to assure that cleancache_invalidate_fs is called on every superblock free Date: Mon, 12 Mar 2012 14:38:25 +0100 Message-ID: <20120312133825.GF5998@quack.suse.cz> References: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: linux-fsdevel@vger.kernel.org, linux-btrfs@vger.kernel.org, linux-ext4@vger.kernel.org, ocfs2-devel@oss.oracle.com, dan.magenheimer@oracle.com, fschmaus@gmail.com, linux-mm@kvack.org, ilendir@googlemail.com, sjenning@linux.vnet.ibm.com, konrad.wilk@oracle.com, i4passt@lists.informatik.uni-erlangen.de, ngupta@vflare.org To: Andor Daam Return-path: In-Reply-To: List-ID: Hello, On Fri 09-03-12 14:40:22, Andor Daam wrote: > Is it ever possible for a superblock for a mounted filesystem to be > free'd without a previous call to unmount the filesystem? No, I don't think so (well, except for cases where we do not manage to fully setup the superblock). But be aware that mount/umount need not be really the entry points you are looking for since filesystem can be mounted several times. Rather deactivate_locked_supers() is the place you are looking for... > I need to be certain that the function cleancache_invalidate_fs, which is > at the moment called by deactivate_locked_super (fs/super.c) [1], is > called before every free on a superblock of cleancache-enabled > filesystems. Is this already the case or are there situations in which > this does not happen? > > It would be interesting to know this, as we are planning to have > cleancache save pointers to superblocks of every mounted > cleancache-enabled filesystem [2] and it would be fatal if a > superblock is free'd without cleancache being notified. Honza -- Jan Kara SUSE Labs, CR