Hi. Currently fdatasync is identical to fsync in ext3,4. I think fdatasync should skip journal flush in data=ordered and data=writeback mode because this syscall is not required to synchronize the metadata. My patch as below is similar to the approach of GFS2's fsync code(gfs2_fsync). Thanks. Signed-off-by :Hisashi Hifumi <hifumi.hisashi@xxxxxxxxxxxxx> diff -Nrup linux-2.6.24-rc2.org/fs/ext3/fsync.c linux-2.6.24-rc2/fs/ext3/fsync.c --- linux-2.6.24-rc2.org/fs/ext3/fsync.c 2007-11-07 06:57:46.000000000 +0900 +++ linux-2.6.24-rc2/fs/ext3/fsync.c 2007-11-15 17:50:24.000000000 +0900 @@ -72,6 +72,9 @@ int ext3_sync_file(struct file * file, s goto out; } + if (datasync) + goto out; + /* * The VFS has written the file data. If the inode is unaltered * then we need not start a commit. diff -Nrup linux-2.6.24-rc2.org/fs/ext4/fsync.c linux-2.6.24-rc2/fs/ext4/fsync.c --- linux-2.6.24-rc2.org/fs/ext4/fsync.c 2007-11-07 06:57:46.000000000 +0900 +++ linux-2.6.24-rc2/fs/ext4/fsync.c 2007-11-15 17:50:54.000000000 +0900 @@ -72,6 +72,9 @@ int ext4_sync_file(struct file * file, s goto out; } + if (datasync) + goto out; + /* * The VFS has written the file data. If the inode is unaltered * then we need not start a commit.
Attachment:
patch-2624rc2-ext34-fdatasync.txt
Description: Binary data
