From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx202.postini.com [74.125.245.202]) by kanga.kvack.org (Postfix) with SMTP id DA2C96B002C for ; Thu, 1 Mar 2012 07:23:22 -0500 (EST) Date: Thu, 1 Mar 2012 13:23:19 +0100 From: Jan Kara Subject: Re: [PATCH 00/11 v2] Push file_update_time() into .page_mkwrite Message-ID: <20120301122319.GE4385@quack.suse.cz> References: <1330602103-8851-1-git-send-email-jack@suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1330602103-8851-1-git-send-email-jack@suse.cz> Sender: owner-linux-mm@kvack.org List-ID: To: Andrew Morton Cc: linux-mm@kvack.org, LKML , Al Viro , linux-fsdevel@vger.kernel.org, dchinner@redhat.com, Jan Kara , Jaya Kumar , Sage Weil , ceph-devel@vger.kernel.org, Steve French , linux-cifs@vger.kernel.org, Eric Van Hensbergen , Ron Minnich , Latchesar Ionkov , v9fs-developer@lists.sourceforge.net, Miklos Szeredi , fuse-devel@lists.sourceforge.net, Steven Whitehouse , cluster-devel@redhat.com, Greg Kroah-Hartman Bah, the subject should have been 0/9... Sorry. Honza On Thu 01-03-12 12:41:34, Jan Kara wrote: > Hello, > > to provide reliable support for filesystem freezing, filesystems need to have > complete control over when metadata is changed. In particular, > file_update_time() calls from page fault code make it impossible for > filesystems to prevent inodes from being dirtied while the filesystem is > frozen. > > To fix the issue, this patch set changes page fault code to call > file_update_time() only when ->page_mkwrite() callback is not provided. If the > callback is provided, it is the responsibility of the filesystem to perform > update of i_mtime / i_ctime if needed. We also push file_update_time() call > to all existing ->page_mkwrite() implementations if the time update does not > obviously happen by other means. If you know your filesystem does not need > update of modification times in ->page_mkwrite() handler, please speak up and > I'll drop the patch for your filesystem. > > As a side note, an alternative would be to remove call of file_update_time() > from page fault code altogether and require all filesystems needing it to do > that in their ->page_mkwrite() implementation. That is certainly possible > although maybe slightly inefficient and would require auditting 100+ > vm_operations_structs *shiver*. > > Changes since v1: > * Dropped patches for filesystems which don't need them > * Added some acks > * Improved sysfs patch by Alex Elder's suggestion > > Andrew, would you be willing to merge these patches via your tree? > > Honza > > CC: Jaya Kumar > CC: Sage Weil > CC: ceph-devel@vger.kernel.org > CC: Steve French > CC: linux-cifs@vger.kernel.org > CC: Eric Van Hensbergen > CC: Ron Minnich > CC: Latchesar Ionkov > CC: v9fs-developer@lists.sourceforge.net > CC: Miklos Szeredi > CC: fuse-devel@lists.sourceforge.net > CC: Steven Whitehouse > CC: cluster-devel@redhat.com > CC: Greg Kroah-Hartman > -- > To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- Jan Kara SUSE Labs, CR -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org