ext4: skip conversion of uninit extents after direct IO if there isn't any
At the end of direct I/O operation, ext4_ext_direct_IO() always called
ext4_convert_unwritten_extents(), regardless of whether there were any
unwritten extents involved in the I/O or not.
This commit adds a state flag so that ext4_ext_direct_IO() only calls
ext4_convert_unwritten_extents() when necessary.
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c
index 441716f..e991ae2 100644
--- a/fs/ext4/extents.c
+++ b/fs/ext4/extents.c
@@ -3048,12 +3048,18 @@
ret = ext4_split_unwritten_extents(handle,
inode, path, iblock,
max_blocks, flags);
- /* flag the io_end struct that we need convert when IO done */
+ /*
+ * Flag the inode(non aio case) or end_io struct (aio case)
+ * that this IO needs to convertion to written when IO is
+ * completed
+ */
if (io)
io->flag = DIO_AIO_UNWRITTEN;
+ else
+ EXT4_I(inode)->i_state |= EXT4_STATE_DIO_UNWRITTEN;
goto out;
}
- /* DIO end_io complete, convert the filled extent to written */
+ /* async DIO end_io complete, convert the filled extent to written */
if (flags == EXT4_GET_BLOCKS_DIO_CONVERT_EXT) {
ret = ext4_convert_unwritten_extents_dio(handle, inode,
path);
@@ -3295,10 +3301,16 @@
* To avoid unecessary convertion for every aio dio rewrite
* to the mid of file, here we flag the IO that is really
* need the convertion.
- *
+ * For non asycn direct IO case, flag the inode state
+ * that we need to perform convertion when IO is done.
*/
- if (io && flags == EXT4_GET_BLOCKS_DIO_CREATE_EXT)
- io->flag = DIO_AIO_UNWRITTEN;
+ if (flags == EXT4_GET_BLOCKS_DIO_CREATE_EXT) {
+ if (io)
+ io->flag = DIO_AIO_UNWRITTEN;
+ else
+ EXT4_I(inode)->i_state |=
+ EXT4_STATE_DIO_UNWRITTEN;;
+ }
}
err = ext4_ext_insert_extent(handle, inode, path, &newex, flags);
if (err) {
