2.6.38: Quota over NFS4

[Adam Lackorzynski <adam@os.inf.tu-dresden.de>]

Hello,

I'm seeing a problem with quotas in a system where the server running
2.6.38 exports an XFS filesystem via NFS4 to a client. The client kernel
version does not seem to play a role, checked with 2.6.38, 2.6.37 and
2.6.36. The following script and output show the problem:

#! /bin/sh

quota | grep home
du
cp /bin/ls x1
du
cat x1 > /dev/null
rm x1
du
quota | grep home

Output:

   homes:/home/ 8194720  9072000 9174400          403670  500000  550000        
0       .
96      .
0       .
   homes:/home/ 8194816  9072000 9174400          403671  500000  550000        


As can be seen the 96 kb are still accounted on the quota of the user.
Removing the 'cat' command from the script makes the quota be ok again
(original value). Also mounting via nfs3 does not exhibit it, same for running
the script on the nfs-server directly.

Client mount options are:
homes:/home/ /home nfs4 rw,nosuid,nodev,relatime,vers=4,rsize=1048576,wsize=1048576,namlen=255,hard,proto=tcp,port=0,timeo=600,retrans=2,sec=sys,clientaddr=1.2.3.3,minorversion=0,local_lock=none,addr=1.2.3.4 0 0

Server mount options are:
/dev/mapper/vg-homefs /home xfs rw,nosuid,nodev,relatime,attr2,usrquota 0 0




Thanks,
Adam
-- 
Adam                 adam@os.inf.tu-dresden.de
  Lackorzynski         http://os.inf.tu-dresden.de/~adam/