NFSv2 Wrong FS Size

[perryh at pluto.rain.com]

> > > you could rebuild "df" to print its numbers as unsigned
> > > instead of signed.  Just watch out if your local filesystems
> > > start eating into their 8% reserve, since they'll start
> > > reporting huge values.
> > 
> > Or patch "df" to print local filesystem sizes as signed -- so
> > that the reserve reporting still works -- and NFS as unsigned
> > to match the spec.
>
> That works as long as you don't NFS-mount other FreeBSD systems
> with overfull drives :)

Looking at this a little more closely, it appears that the "struct
statfs" returned by statfs(2) and friends tells the whole story,
using 64-bit values most of which are defined as unsigned.  (Only
f_bavail and f_ffree -- the number of blocks and inodes available to
non-superusers -- are defined as signed.)  The code that converts
from the 32-bit NFSv2 to the 64-bit "struct statfs" values seems
more likely to be somewhere in NFS than in df(1).