Modify CpuPageTableLib code to enable PAE paging.
In PageTableMap() API:
When creating new PAE page table, after creating page table,
set all MustBeZero fields of 4 PDPTE to 0. The MustBeZero
fields are treated as RW and other attributes by the common
map logic. So they might be set to 1.
When updating exsiting PAE page table, the special steps are:
1.Prepare 4K-aligned 32bytes memory in stack for 4 temp PDPTE.
2.Copy original 4 PDPTE to the 4 temp PDPTE and set the RW,
UserSupervisor to 1 and set Nx of 4 temp PDPTE to 0.
4.After updating the page table, set the MustBeZero fields of
4 temp PDPTE to 0.
5.Copy the temp PDPTE to original PDPTE.
In PageTableParse() API, also create 4 temp PDPTE in stack.
Copy original 4 PDPTE to the 4 temp PDPTE. Then set the RW,
UserSupervisor to 1 and set Nx of 4 temp PDPTE to 0. Finally
use the address of temp PDPTE as the page table address.
Signed-off-by: Dun Tan <dun.tan@intel.com>
Cc: Eric Dong <eric.dong@intel.com>
Reviewed-by: Ray Ni <ray.ni@intel.com>
Cc: Rahul Kumar <rahul1.kumar@intel.com>
Tested-by: Gerd Hoffmann <kraxel@redhat.com>
Acked-by: Gerd Hoffmann <kraxel@redhat.com>
Support PAE paging for PageTableParse API in CpuPageTableLib.
Signed-off-by: Dun Tan <dun.tan@intel.com>
Cc: Eric Dong <eric.dong@intel.com>
Reviewed-by: Ray Ni <ray.ni@intel.com>
Cc: Rahul Kumar <rahul1.kumar@intel.com>
The lib includes two APIs:
* PageTableMap
It creates/updates mapping from LA to PA.
The implementation only supports paging structures used in 64bit
mode now. PAE paging structure support will be added in future.
* PageTableParse
It parses the page table and returns the mapping relations in an
array of IA32_MAP_ENTRY.
It passed some stress tests. These test code will be upstreamed in
other patches following edk2 Unit Test framework.
Signed-off-by: Ray Ni <ray.ni@intel.com>
Reviewed-by: Eric Dong <eric.dong@intel.com>
Dun Tan
Ray Ni