From: Jan Kara Subject: Re: [PATCH 0/3] Rewrite ext4_page_mkwrite, fix fs freezing Date: Wed, 11 May 2011 19:03:17 +0200 Message-ID: <20110511170317.GM5057@quack.suse.cz> References: <1305066574-1573-1-git-send-email-jack@suse.cz> <20110511003012.GC6933@thunk.org> <20110511092752.GA5057@quack.suse.cz> <20110511164836.GG18929@tux1.beaverton.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Jan Kara , Ted Ts'o , linux-ext4@vger.kernel.org, linux-fsdevel@vger.kernel.org To: "Darrick J. Wong" Return-path: Content-Disposition: inline In-Reply-To: <20110511164836.GG18929@tux1.beaverton.ibm.com> Sender: linux-fsdevel-owner@vger.kernel.org List-Id: linux-ext4.vger.kernel.org On Wed 11-05-11 09:48:36, Darrick J. Wong wrote: > On Wed, May 11, 2011 at 11:27:52AM +0200, Jan Kara wrote: > > On Tue 10-05-11 20:30:12, Ted Tso wrote: > > > On Wed, May 11, 2011 at 12:29:31AM +0200, Jan Kara wrote: > > > > > > > > following three patches reimplement ext4_page_mkwrite() so that it returns > > > > locked pages (which is necessary for stable pages work and also for fixing of > > > > freezing code). As a bonus we also avoid taking i_alloc_sem as it's not > > > > necessary and use generic block_page_mkwrite() helper. The common delalloc > > > > path should be more straightforward now. > > > > > > How does this relate to Darrick Wong's patches? Are your patches in > > > addition to or instead of his? > > It's in addition to those (although with my patches, a generic change to > > block_page_mkwrite() would be enough for ext4). If you plan to merge those > > now, I can rediff on top of those patches. > > Just to be clear, your new __block_page_mkwrite still needs a patch to call > wait_on_page_writeback to provide stable page writes, correct? Correct. > I think we'd still need a wait_on_page_writeback for the "all buffers are > mapped" VM_FAULT_LOCKED exit from ext4_page_mkwrite? Ah, right, I forgot about that one. Honza -- Jan Kara SUSE Labs, CR