linux-kernel - [PATCH -next v2 18/22] ext4: do not order data for inodes using buffered iomap path

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Message-ID: <20260203062523.3869120-19-yi.zhang@huawei.com>
Date: Tue,  3 Feb 2026 14:25:18 +0800
From: Zhang Yi <yi.zhang@...wei.com>
To: linux-ext4@...r.kernel.org
Cc: linux-fsdevel@...r.kernel.org,
	linux-kernel@...r.kernel.org,
	tytso@....edu,
	adilger.kernel@...ger.ca,
	jack@...e.cz,
	ojaswin@...ux.ibm.com,
	ritesh.list@...il.com,
	hch@...radead.org,
	djwong@...nel.org,
	yi.zhang@...wei.com,
	yi.zhang@...weicloud.com,
	yizhang089@...il.com,
	libaokun1@...wei.com,
	yangerkun@...wei.com,
	yukuai@...as.com
Subject: [PATCH -next v2 18/22] ext4: do not order data for inodes using buffered iomap path

In the iomap buffered I/O path, we always allocate unwritten blocks when
doing append write, and flush data when doing partial block truncate
down. Therefore, there is no risk of exposing stale data, disable
ordered data mode for the iomap buffered I/O path.

Signed-off-by: Zhang Yi <yi.zhang@...wei.com>
---
 fs/ext4/ext4_jbd2.h | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/fs/ext4/ext4_jbd2.h b/fs/ext4/ext4_jbd2.h
index 63d17c5201b5..7061c7188053 100644
--- a/fs/ext4/ext4_jbd2.h
+++ b/fs/ext4/ext4_jbd2.h
@@ -383,7 +383,12 @@ static inline int ext4_should_journal_data(struct inode *inode)
 
 static inline int ext4_should_order_data(struct inode *inode)
 {
-	return ext4_inode_journal_mode(inode) & EXT4_INODE_ORDERED_DATA_MODE;
+	/*
+	 * inodes using the iomap buffered I/O path do not use the
+	 * ordered data mode.
+	 */
+	return !ext4_inode_buffered_iomap(inode) &&
+		(ext4_inode_journal_mode(inode) & EXT4_INODE_ORDERED_DATA_MODE);
 }
 
 static inline int ext4_should_writeback_data(struct inode *inode)
-- 
2.52.0