From: Jan Kara Subject: Re: [PATCH 0/3] Make block_page_mkwrite() handle frozen fs (V2) Date: Thu, 19 May 2011 14:30:29 +0200 Message-ID: <20110519123029.GI8417@quack.suse.cz> References: <1305731882-8334-1-git-send-email-jack@suse.cz> <20110518180022.GM18929@tux1.beaverton.ibm.com> Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="ZGiS0Q5IWpPtfppv" Cc: Jan Kara , linux-fsdevel@vger.kernel.org, linux-ext4@vger.kernel.org, Al Viro , tytso@mit.edu, Christoph Hellwig To: "Darrick J. Wong" Return-path: Content-Disposition: inline In-Reply-To: <20110518180022.GM18929@tux1.beaverton.ibm.com> Sender: linux-fsdevel-owner@vger.kernel.org List-Id: linux-ext4.vger.kernel.org --ZGiS0Q5IWpPtfppv Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Wed 18-05-11 11:00:22, Darrick J. Wong wrote: > On Wed, May 18, 2011 at 05:17:59PM +0200, Jan Kara wrote: > > > > Hi, > > > > this is a second version of my patches which rewrite ext4_page_mkwrite() to > > use generic helper. When we are already changing this code, I also added proper > > handling of frozen filesystem there in patch 2/3. I've incorporated suggestions > > from Christoph in the patches which resulted in some patch reorg. I'd like to > > get these patches reviewed and then get them merged possibly via ext4-tree > > (although the first two patches might go via Al but that would complicate > > merging of ext4 part where I expect more conflicts with ongoing work). > > Do you want me to generate a patch to add wait_on_page_writeback to the > appropriate place(s) in your new *_page_mkwrite functions, or do you plan to > add them yourself? > > (iow: is there an order for pushing these ext4_page_mkwrite changes?) Attached is a rebase of your block_page_mkwrite change on top of my patches. I'm not sure what is the actual status your series - have you pushed VFS changes to Al? Honza --ZGiS0Q5IWpPtfppv Content-Type: text/x-patch; charset=us-ascii Content-Disposition: attachment; filename="0001-vfs-Wait-in-__block_page_mkwrite-for-IO-to-finish.patch" >From 408d0a667ebdc7edd24d05c8de4b42cc1629e84f Mon Sep 17 00:00:00 2001 From: Darrick J. Wong Date: Thu, 19 May 2011 14:14:11 +0200 Subject: [PATCH] vfs: Wait in __block_page_mkwrite for IO to finish For filesystems such as nilfs2 and xfs that use block_page_mkwrite, modify that function to wait for pending writeback before allowing the page to become writable. This is needed to stabilize pages during writeback for those two filesystems. Signed-off-by: Darrick J. Wong Signed-off-by: Jan Kara --- fs/buffer.c | 2 ++ 1 files changed, 2 insertions(+), 0 deletions(-) diff --git a/fs/buffer.c b/fs/buffer.c index b0675bf..161685d 100644 --- a/fs/buffer.c +++ b/fs/buffer.c @@ -2365,6 +2365,8 @@ int __block_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf, if (unlikely(ret < 0)) goto out_unlock; + /* Wait so that we don't change page under IO */ + wait_on_page_writeback(page); /* * Freezing in progress? We check after the page is marked dirty and * with page lock held so if the test here fails, we are sure freezing -- 1.7.1 --ZGiS0Q5IWpPtfppv--