Description of problem:
while I/O is going in a directory having quota implemented. quotad.log reports logs of this kind
0.33/xlator/features/quotad.so(quotad_aggregator_get_frame_from_req+0x61) [0x7f128a6a8a41]))) 0-client_t: null client
[2014-11-20 03:51:01.065727] E [client_t.c:327:gf_client_ref] (-->/usr/lib64/libgfrpc.so.0(rpcsvc_handle_rpc_call+0x295) [0x38f4009b15] (-->/usr/lib64/glusterfs/3.6.0.33/xlator/features/quotad.so(quotad_aggregator_lookup+0xc1) [0x7f128a6a91f1] (-->/usr/lib64/glusterfs/3.6.0.33/xlator/features/quotad.so(quotad_aggregator_get_frame_from_req+0x61) [0x7f128a6a8a41]))) 0-client_t: null client
[2014-11-20 18:41:36.268946] E [client_t.c:327:gf_client_ref] (-->/usr/lib64/libgfrpc.so.0(rpcsvc_handle_rpc_call+0x295) [0x38f4009b15] (-->/usr/lib64/glusterfs/3.6.0.33/xlator/features/quotad.so(quotad_aggregator_getlimit+0x1d8) [0x7f128a6a97b8] (-->/usr/lib64/glusterfs/3.6.0.33/xlator/features/quotad.so(quotad_aggregator_get_frame_from_req+0x61) [0x7f128a6a8a41]))) 0-client_t: null client

Version-Release number of selected component (if applicable):
glusterfs-3.6.0.33-1.el6rhs.x86_64

How reproducible:
always

Steps to Reproduce:
1. create volume of type 6x2, start it
2. enable quota
3. mount the volume over nfs
4. create a directory 
5. set quota limit of 100GB on /
6. set quota limit of 25GB on directory
7. start creating files of random size inside the directory.

Actual results:
logs as mentioned above in quotad.log

Expected results:
Error while just adding files is not expected.

Additional info: