Remove dqptr_sem to make quota code scalable: Remove the dqptr_sem,
accessing inode->i_dquot now protected by dquot_srcu, and changing
inode->i_dquot is now serialized by dq_data_lock.
Signed-off-by: NLai Siyao <lai.siyao@intel.com>
Signed-off-by: NNiu Yawei <yawei.niu@intel.com>
Signed-off-by: NJan Kara <jack@suse.cz>