Jan Kara [off-list ref] wrote:

quoted

		unsigned long long	st_blocks;

  When we are doing this, can we please also change 'st_blocks' to
'st_bytes'? We track space usage in kernel in bytes for a long time so it
would be nice to propagate it to userspace via stat instead of a special
ioctl (at least quotacheck(8) needs to know the exact value).

Ummm...  I'm not sure about that.  Ideally, every field that is provided in
the current stat() buffer must still be there.  On the other hand, since
they're going to be moved around, presumably there will be a userspace
translation layer.

David