Few days back I posted a patchset to allow pquota and gquota to be used
together. I have a question in that context.
In order for the user space to get the stats for pguota and gquota
together (quotactl command Q_XGETQSTAT), I need to add a field to
fs_quota_stat. So, I have to change the version number.
But, the version number is only set in the kernel and not checked. Which
means the kernel cannot know what size of the fs_quota_stat data
structure the user space has provided in order to decide if the kernel
can copy the newer (bigger) data structure to the user space or not.
One option I see is to add a new command to the ioctl.
Is there any other options ? ( or am I totally missing it :) ?