linux-ext4 - [PATCH 4/4] ext4: order mode should not take effect for DIO

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Message-ID: <20251027122303.1146352-4-yangerkun@huawei.com>
Date: Mon, 27 Oct 2025 20:23:03 +0800
From: Yang Erkun <yangerkun@...wei.com>
To: <linux-ext4@...r.kernel.org>, <tytso@....edu>, <adilger.kernel@...ger.ca>,
	<jack@...e.cz>
CC: <yi.zhang@...wei.com>, <libaokun1@...wei.com>, <yangerkun@...wei.com>,
	<yangerkun@...weicloud.com>
Subject: [PATCH 4/4] ext4: order mode should not take effect for DIO

Since the size will be updated after the DIO completes, the data
will not be shown to userspace before that.

Signed-off-by: Yang Erkun <yangerkun@...wei.com>
---
 fs/ext4/ext4.h              | 2 ++
 fs/ext4/inode.c             | 5 +++--
 include/trace/events/ext4.h | 1 +
 3 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index 5a035d0e2761..bad43d047224 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -715,6 +715,8 @@ enum {
 #define EXT4_GET_BLOCKS_METADATA_NOFAIL		0x0020
 	/* Don't normalize allocation size (used for fallocate) */
 #define EXT4_GET_BLOCKS_NO_NORMALIZE		0x0040
+	/* Get blocks from DIO */
+#define EXT4_GET_BLOCKS_DIO			0x0080
 	/* Convert written extents to unwritten */
 #define EXT4_GET_BLOCKS_CONVERT_UNWRITTEN	0x0100
 	/* Write zeros to newly created written extents */
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 3d8ada26d5cd..168dbcc9e921 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -818,6 +818,7 @@ int ext4_map_blocks(handle_t *handle, struct inode *inode,
 		if (map->m_flags & EXT4_MAP_NEW &&
 		    !(map->m_flags & EXT4_MAP_UNWRITTEN) &&
 		    !(flags & EXT4_GET_BLOCKS_ZERO) &&
+		    !(flags & EXT4_GET_BLOCKS_DIO) &&
 		    !ext4_is_quota_file(inode) &&
 		    ext4_should_order_data(inode)) {
 			loff_t start_byte =
@@ -3729,9 +3730,9 @@ static int ext4_iomap_alloc(struct inode *inode, struct ext4_map_blocks *map,
 	 * happening and thus expose allocated blocks to direct I/O reads.
 	 */
 	else if (((loff_t)map->m_lblk << blkbits) >= i_size_read(inode))
-		m_flags = EXT4_GET_BLOCKS_CREATE;
+		m_flags = EXT4_GET_BLOCKS_CREATE | EXT4_GET_BLOCKS_DIO;
 	else if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))
-		m_flags = EXT4_GET_BLOCKS_IO_CREATE_EXT;
+		m_flags = EXT4_GET_BLOCKS_IO_CREATE_EXT | EXT4_GET_BLOCKS_DIO;
 
 	if (flags & IOMAP_ATOMIC)
 		ret = ext4_map_blocks_atomic_write(handle, inode, map, m_flags,
diff --git a/include/trace/events/ext4.h b/include/trace/events/ext4.h
index ada2b9223df5..de6d848f2e37 100644
--- a/include/trace/events/ext4.h
+++ b/include/trace/events/ext4.h
@@ -43,6 +43,7 @@ struct partial_cluster;
 	{ EXT4_GET_BLOCKS_CONVERT,		"CONVERT" },		\
 	{ EXT4_GET_BLOCKS_METADATA_NOFAIL,	"METADATA_NOFAIL" },	\
 	{ EXT4_GET_BLOCKS_NO_NORMALIZE,		"NO_NORMALIZE" },	\
+	{ EXT4_GET_BLOCKS_DIO,			"DIO" },		\
 	{ EXT4_GET_BLOCKS_CONVERT_UNWRITTEN,	"CONVERT_UNWRITTEN" },  \
 	{ EXT4_GET_BLOCKS_ZERO,			"ZERO" },		\
 	{ EXT4_GET_BLOCKS_IO_SUBMIT,		"IO_SUBMIT" },		\
-- 
2.39.2