ext4: Check if inode uses extents in ext4_inode_can_atomic_write()

riteshharjani · tytso · commit 1c972b1d13dd · 2025-05-20T10:31:12.000-04:00
EXT4 only supports doing atomic write on inodes which uses extents, so add a check in ext4_inode_can_atomic_write() which gets called during open. Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com> Acked-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com> Link: https://patch.msgid.link/86bb502c979398a736ab371d8f35f6866a477f6c.1747337952.git.ritesh.list@gmail.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
@@ -3870,7 +3870,9 @@ static inline int ext4_buffer_uptodate(struct buffer_head *bh)
 static inline bool ext4_inode_can_atomic_write(struct inode *inode)
 {
 
-	return S_ISREG(inode->i_mode) && EXT4_SB(inode->i_sb)->s_awu_min > 0;
+	return S_ISREG(inode->i_mode) &&
+		ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS) &&
+		EXT4_SB(inode->i_sb)->s_awu_min > 0;
 }
 
 extern int ext4_block_write_begin(handle_t *handle, struct folio *folio,

Original file line number	Diff line number	Diff line change
`@@ -3870,7 +3870,9 @@ static inline int ext4_buffer_uptodate(struct buffer_head *bh)`
`3870`	`3870`	`static inline bool ext4_inode_can_atomic_write(struct inode *inode)`
`3871`	`3871`	`{`
`3872`	`3872`
`3873`		`- return S_ISREG(inode->i_mode) && EXT4_SB(inode->i_sb)->s_awu_min > 0;`
	`3873`	`+ return S_ISREG(inode->i_mode) &&`
	`3874`	`+ ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS) &&`
	`3875`	`+ EXT4_SB(inode->i_sb)->s_awu_min > 0;`
`3874`	`3876`	`}`
`3875`	`3877`
`3876`	`3878`	`extern int ext4_block_write_begin(handle_t handle, struct folio folio,`