Description of problem:
=========================
When writes are in progress from cifs mount, if we perform any volume set operations which changes the client graph, the writes fails with "Bad file descriptor" 

Version-Release number of selected component (if applicable):
===============================================================
glusterfs 3.4.0.30rhs built on Aug 30 2013 08:15:37

How reproducible:
====================
Often

Steps to Reproduce:
=====================
1.Create a replicate volume. Start the volume. 

2.Create a cifs mount. 

3.From mount point execute: "for i in `seq 1 100`; do echo "Hello $i" > file.1 ; sleep 1 ; done

4. while writes on file are in progress , set "write-behind" to "off" from one of the storage node. 

Actual results:
==============
root@darrel [Sep-05-2013-10:14:47] > for i in `seq 1 100`; do echo "Hello $i" >&5 ; sleep 1 ; done
-bash: echo: write error: Bad file descriptor
-bash: echo: write error: Bad file descriptor
-bash: echo: write error: Bad file descriptor
-bash: echo: write error: Bad file descriptor
-bash: echo: write error: Bad file descriptor
-bash: echo: write error: Bad file descriptor
-bash: echo: write error: Bad file descriptor
-bash: echo: write error: Bad file descriptor
-bash: echo: write error: Bad file descriptor
-bash: echo: write error: Bad file descriptor

Expected results:
===================
writes shouldn't file. 

Additional info: