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From:   Jaegeuk Kim <jaegeuk@kernel.org>
To:     linux-kernel@vger.kernel.org,
        linux-f2fs-devel@lists.sourceforge.net, kernel-team@android.com
Cc:     Jaegeuk Kim <jaegeuk@kernel.org>, stable@vger.kernel.org
Subject: [PATCH] f2fs: flush data when enabling checkpoint back
Date:   Tue, 26 Jan 2021 17:44:34 -0800
Message-Id: <20210127014434.3431893-1-jaegeuk@kernel.org>
MIME-Version: 1.0
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During checkpoint=disable period, f2fs bypasses all the synchronous IOs such as
sync and fsync. So, when enabling it back, we must flush all of them in order
to keep the data persistent. Otherwise, suddern power-cut right after enabling
checkpoint will cause data loss.

Fixes: 4354994f097d ("f2fs: checkpoint disabling")
Cc: stable@vger.kernel.org
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
---
 fs/f2fs/super.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
index 359cc5a2f8f5..073b51af62c8 100644
--- a/fs/f2fs/super.c
+++ b/fs/f2fs/super.c
@@ -1887,6 +1887,9 @@ static int f2fs_disable_checkpoint(struct f2fs_sb_info *sbi)
 
 static void f2fs_enable_checkpoint(struct f2fs_sb_info *sbi)
 {
+	/* we should flush all the data to keep data consistency */
+	sync_inodes_sb(sbi->sb);
+
 	down_write(&sbi->gc_lock);
 	f2fs_dirty_to_prefree(sbi);
 
-- 
2.30.0.280.ga3ce27912f-goog