On Fri, Sep 25, 2015 at 1:12 AM, Andreas Dilger [off-list ref] wrote:

On Sep 13, 2015, at 2:20 PM, Li Xi [off-list ref] wrote:

quoted

The following patches propose an implementation of project quota
support for ext4. A project is an aggregate of unrelated inodes
which might scatter in different directories. Inodes that belong
to the same project possess an identical identification i.e.
'project ID', just like every inode has its user/group
identification. The following patches add project quota as
supplement to the former uer/group quota types.

We discussed this on the ext4 developer concall today and tried to
move the landing of these patches forward.  Some notes below:

- Ted: agreed to reserve EXT4_FEATURE_RO_COMPAT_PROJECT, s_prj_quota_inum,
  EXT4_PROJINHERIT_FL, and i_projid fields for use by project quota to
  avoid compatibility issues if patches are not landed immediately.
   - Ted: to do final check of inode flag value
   - ext4 project quota inode does not need to use a reserved inode, but
     could after Jan's patch to increase reserved inodes lands
- Li Xi: identify xfstests subtests that are exercising project quota
   - submit patches to xfstests that will activate them for ext4
   - keep in ext4 xfstests for testing until patches land upstream
   - this needs to be done before landing to ensure ext4 code works
- Li Xi: document the behaviour of project quota (if no existing
  document exists for XFS already), some of this is already below
   - update man pages for df(1) and statfs(2) for subdir with project ID
     (i.e. that it returns only quota usage and limit for project ID)
   - Ted: where should document go? linux/Documentation/fs? ext4 wiki?
   - not a requirement for testing, can be done after landing

- All: decide on a common tool for setting project ID on file/directory
   - don't want to require xfsutils in order to use project quota
   - start with chattr (using FS_IOC_FS{GET,SET}XATTR) in e2fsprogs
     - allows testing project quota with e2fsprogs/ext4
   - chproj (like chown/chgrp) would also be an option
     - needs more discussion/development effort, goes into fileutils
   - this doesn't need to be decided immediately, and both could be done

Hi,

I've pushed the patch of Ext4 as well as e2fsprogs. Shilong has added test
suits for ext4 project quota in xfstest, and will push patches soon. I
will write
necessary documentation both for manual and linux/Documentation/fs.

Hopefully, at least the kernel patches of ext4 project quota will be merged
soon.

Regards,
Li Xi