Revert "LU-4139 quota: improve write performance when over softlimit"

This reverts commit 74eb386b18ad5745c499f6c622512dcadaa4f400.

This patch to be reverted was based on patch set #1 on Oct 28th, 2013.
The final patch landed to b2_4 branch and master branch were patch set #3.
LU-4139 quota: improve write performance when over softlimit

To improve the write performance when over softlimit, we choose
to lose some grace time accuracy: shrinking the qunit size to
(4 * least_qunit_size) instead of least_qunit_size.

Signed-off-by: Niu Yawei <yawei.niu@intel.com>
Change-Id: I20e341d53979ac42227197ec6fa04dd38974073f
Reviewed-on: http://review.whamcloud.com/8078
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Johann Lombardi <johann.lombardi@intel.com>
Reviewed-by: Fan Yong <fan.yong@intel.com>
LU-4403 mds: extra lock during resend lock lookup.

Lock the resource when the MDS is trying to lookup the lock for
resend request(in mdt_intent_fixup_resent). Otherwise, if the
lock is being released, fixup_resent will return a released lock,
which will cause LBUG when this lock is being released later.

Signed-off-by: wang di <di.wang@intel.com>
Change-Id: I3c1aab345fcbb971a85aaa6aac92f22439560ff3