One of the functionalities of CpuDxe is to update memory paging attributes.
If page table protection is applied, it must be disabled temporarily before
any attributes update and enabled again afterwards.
This patch makes use of the same way as DxeIpl to allocate page table memory
from reserved memory pool, which helps to reduce potential "split" operation
and recursive calling of SetMemorySpaceAttributes().
Laszlo (lersek@redhat.com) did a regression test on QEMU virtual platform with
one middle version of this series patch. The details can be found at
https://lists.01.org/pipermail/edk2-devel/2017-December/018625.html
There're a few changes after his work.
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Star Zeng <star.zeng@intel.com>
Cc: Eric Dong <eric.dong@intel.com>
Cc: Ruiyu Ni <ruiyu.ni@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
Reviewed-by: Jiewen Yao <jiewen.yao@intel.com>
Add memory attribute setting in CpuArch protocol.
Previous SetMemoryAttributes() API only supports cache attribute setting.
This patch updated SetMemoryAttributes() API to support memory attribute
setting by updating CPU page table.
Cc: Jeff Fan <jeff.fan@intel.com>
Cc: Michael Kinney <michael.d.kinney@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Jiewen Yao <jiewen.yao@intel.com>
Reviewed-by: Jeff Fan <jeff.fan@intel.com>