http://documentation-devel.engineering.redhat.com/docs/en-US/Red_Hat_Storage/2.1/html/Administration_Guide/chap-User_Guide-Dir_Quota-Remove.html


You can remove set disk limit, if you do not want quota anymore.
[shanks] Can we please have the above rephrased ?


To remove disk limit
[shanks] disk limit usage


Remove disk limit set on a particular directory using the following command:
[shanks] disk limit usage


# gluster volume quota VOLNAME remove /directory-name
[shanks] /<directory-name>


...
For example, to remove the disk limit on /data directory of test-volume:
# gluster volume quota test-volume remove /data
Removed quota limit on /data

should be

# gluster volume quota test-volume remove /data
volume quota : success
...


Also, should give details on removing quota from volume.

[root@server1 ~]# gluster vol quota shanks-quota remove /
volume quota : success
[root@server1 ~]# 

with a note that removing quota from the volume ("/") does not impact quota limit usage on directories.