On Jan 8, 2015, at 1:26 AM, Jan Kara [off-list ref] wrote:

On Tue 09-12-14 13:22:25, Li Xi wrote:

quoted

This patch adds a new internal field of ext4 inode to save project
identifier. Also a new flag EXT4_INODE_PROJINHERIT is added for
inheriting project ID from parent directory.

 I have noticed one thing you apparently changed in v7 of the patch set.
See below.

quoted

diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index 29c43e7..8bd1da9 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h

@@ -377,16 +377,18 @@ struct flex_groups {

#define EXT4_EA_INODE_FL	        0x00200000 /* Inode used for large EA */
#define EXT4_EOFBLOCKS_FL		0x00400000 /* Blocks allocated beyond EOF */
#define EXT4_INLINE_DATA_FL		0x10000000 /* Inode has inline data. */
+#define EXT4_PROJINHERIT_FL		FS_PROJINHERIT_FL /* Create with parents projid */

 How did FS_PROJINHERIT_FL get here? There used to be 0x20000000 in older
version of the patch set which is correct - this definition is defining
ext4 on-disk format. As such it is an ext4 specific flag and should be
definined to a fixed constant independed of any other filesystem. It seems
you are somewhat mixing what is an on-disk format flag value and what is a
flag value passed from userspace. These two may be different things and
you need to convert between the values when getting / setting flags...

Currently the EXT4_*_FL and FS_*_FL values are all identical, and there
is no reason to change that before it is actually needed.  Since the
FS_PROJINHERIT_FL is used via chattr/lsattr from userspace, this value
must also be kept the same in the future to avoid API breakage, so there
is no reason to worry about incompatibilities.

See also the [v8 5/5] patch, which is changing the EXT4_*_FL values to
use FS_*_FL constants, where applicable, so that it is more clear that
these values need to be the same.

Cheers, Andreas