[RFC PATCH 0/3] Allow pquota and gquota to be used together

[Chandra Seetharaman]

Hello All,

Few weeks back I asked for some work on XFS. Christoph suggested
me to make changes to allow pquota and gquota to be used
simultaneously in a filesystem.

All the xfs quota tests ran successfully. Currently running
the full suite.

I am currently working on the user space changes. In the mean
while I wanted to get some feedback on it.

Here are the changes. 

These changes expect the pquotino to be already present in the
disk with a version bit. IOW, only mkfs has the ability to 
create a filesystem with this specific information.

Also, when older superblocks are read, it will be written back
the same way. i.e, no semantic change to the superblock.

1. Expand the on disk XFS_OQUOTA_* to in core XFS_GQUOTA_.* and
   XFS_PQUOTA_.*. But always store as XFS_OQUOTA_.* on disk.

2. Wherever gquota is used, introduce pquota, simply by way of
   defining a macro for pquota(This is to make the changes
   simple and easy to follow).

3. Start using a new field pquotino in on-disk super block, when
   an appropriate version bit is set.

Thanks & Regards,

chandra