Description of problem:
Write data Device or resource busy by client access volume when do gluster volume set testvol_distributed-replicated user.cifs on.

Version-Release number of selected component (if applicable):
gluster-6 extras/hook-scripts/start/post/S30samba-start.sh and ./extras/hook-scripts/set/post/S30samba-set.sh script

How reproducible:
enable gluster cifs and access volume by cifs. Smb client will report Device or resource busy when we echo or do cat command file

Steps to Reproduce:
1.create 2*(2+1) test volume
2.gluster v set test user.cifs on
3.On the client and mount test by cifs
4.create file and echo "11111" >> file, will report Device or resource busy.

Actual results:
can not write or read file

Expected results:
can write or read file as usual

Additional info:
smb client:
mount.cifs //10.10.51.22/gluster-testvol_dispersed /mnt/testvol_dispersed
cd /mnt/testvol_dispersed
cat file 
cat: file: Device or resource busy
echo "11111" >> file 
-bash: file: Device or resource busy