From:   "Theodore Ts'o" <tytso@mit.edu>
To:     Jan Kara <jack@suse.cz>
Cc:     "Theodore Ts'o" <tytso@mit.edu>, linux-ext4@vger.kernel.org
Subject: Re: [PATCH 0/7] ext4: Cleanup data=journal writeback path
Date:   Sun, 19 Feb 2023 00:40:44 -0500
Message-Id: <167678522161.2723470.8525900345936295049.b4-ty@mit.edu>
In-Reply-To: <20230111152736.9608-1-jack@suse.cz>
References: <20230111152736.9608-1-jack@suse.cz>
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On Wed, 11 Jan 2023 16:43:24 +0100, Jan Kara wrote:
> this patch series implements promised cleanup of ext4 data=journal writeback
> path. That way we can get rid of last remnants of old support for .writepage
> callback and mostly unify this writeback path with standard data handling
> modes. We also update some of the stale comments regarding data=journal mode
> along the way.
> 
> Note that patch 3 (ext4: Mark page for delayed dirtying only if it is pinned)
> currently breaks somewhat the data=journal guarantees if mapped page cache is
> used as a buffer for direct IO read because that path does not pin pages yet
> (David Howels is working on it). But I figured this is not a huge deal for a
> cornercase usecase of a cornercase configuration and keeping marking page for
> delayed dirtying unconditionally is problematic as checkpointing dirties the
> page as well so it is effectively permanently added to the journal. It was
> problematic already in the past and happened to work only by luck.
> 
> [...]

Applied, thanks!

[1/7] ext4: Update stale comment about write constraints
      commit: d399906a1bd04c3fbc5bca9057ce992dc9b9e036
[2/7] ext4: Use nr_to_write directly in mpage_prepare_extent_to_map()
      commit: 726432969963b16f817566715b0c7ec537d0283b
[3/7] ext4: Mark page for delayed dirtying only if it is pinned
      commit: 71ace6bd0d47b09d6130014d70f87fcff5ae3e36
[4/7] ext4: Don't unlock page in ext4_bio_write_page()
      commit: 0bcd54cf93e0dcefd121368fa32a478df2c86398
[5/7] ext4: Move page unlocking out of mpage_submit_page()
      commit: 9ff6a9153c8f8a08eb60e0740c32e08cef88545c
[6/7] ext4: Move mpage_page_done() calls after error handling
      commit: b4d26e70a7556ca723d31ac0c6bace0d1ab932b5
[7/7] ext4: Convert data=journal writeback to use ext4_writepages()
      commit: 9b18c23c131ae6a335ef7aa6bf53f1d27a667ed1

Best regards,
-- 
Theodore Ts'o <tytso@mit.edu>