From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Darrick J. Wong" Subject: [RFC PATCH 2/2] jbd: Stabilize pages during writes when in ordered mode Date: Wed, 21 Nov 2012 18:36:45 -0800 Message-ID: <20121122023645.GB32182@blackbox.djwong.org> References: <20121121020027.10225.43206.stgit@blackbox.djwong.org> <20121121020056.10225.15220.stgit@blackbox.djwong.org> <20121121021543.GI10507@quack.suse.cz> <20121121211319.GA32202@blackbox.djwong.org> <20121121213333.GF30250@quack.suse.cz> <20121122084713.69e5b1fc@notabene.brown> <20121122014755.GH8740@blackbox.djwong.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Jan Kara , axboe@kernel.dk, lucho@ionkov.net, ericvh@gmail.com, tytso@mit.edu, rminnich@sandia.gov, viro@zeniv.linux.org.uk, martin.petersen@oracle.com, david@fromorbit.com, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, adilger.kernel@dilger.ca, bharrosh@panasas.com, jlayton@samba.org, v9fs-developer@lists.sourceforge.net, linux-ext4@vger.kernel.org To: NeilBrown Return-path: Content-Disposition: inline In-Reply-To: <20121122014755.GH8740@blackbox.djwong.org> Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-fsdevel.vger.kernel.org When writing buffers out to disk ahead of committing a transaction, set the Stable bit on the page to prevent others from wandering in and modifying the page. Signed-off-by: Darrick J. Wong --- fs/jbd/commit.c | 18 +++++++++++++++++- 1 file changed, 17 insertions(+), 1 deletion(-) diff --git a/fs/jbd/commit.c b/fs/jbd/commit.c index 86b39b1..b1f0eed 100644 --- a/fs/jbd/commit.c +++ b/fs/jbd/commit.c @@ -155,13 +155,29 @@ static int journal_write_commit_record(journal_t *journal, return (ret == -EIO); } +static void end_stable_write_sync(struct buffer_head *bh, int uptodate) +{ + clear_page_stable(bh->b_page); + end_buffer_write_sync(bh, uptodate); +} + static void journal_do_submit_data(struct buffer_head **wbuf, int bufs, int write_op) { int i; for (i = 0; i < bufs; i++) { - wbuf[i]->b_end_io = end_buffer_write_sync; + struct page *p = wbuf[i]->b_page; + if (TestSetPageStable(p)) + wbuf[i]->b_end_io = end_buffer_write_sync; + else + wbuf[i]->b_end_io = end_stable_write_sync; + + if (trylock_page(p)) { + clear_page_dirty_for_io(p); + unlock_page(p); + } + /* We use-up our safety reference in submit_bh() */ submit_bh(write_op, wbuf[i]); }