MdeModulePkg PiSmmCore: Remove a hidden assumption of SMRAM reservation

that assumes the SMRAM reserved range is only at the end of the SMRAM descriptor.

          //
          // This range has reserved area, calculate the left free size
          //
          gSmmCorePrivate->SmramRanges[Index].PhysicalSize = SmramResRegion->SmramReservedStart - gSmmCorePrivate->SmramRanges[Index].CpuStart;

Imagine the following scenario where we just reserve the first page of the SMRAM range:

SMRAM Descriptor:
  Start: 0x80000000
  Size: 0x02000000

Reserved Range:
  Start: 0x80000000
  Size: 0x00001000

In this case the adjustment to the SMRAM range size yields zero: ReservedStart - SMRAM Start is 0x80000000 - 0x80000000 = 0.
So even though most of the range is still free the IPL code decides its unusable.

The problem comes from the email thread: [edk2] PiSmmIpl SMRAM Reservation Logic.
http://thread.gmane.org/gmane.comp.bios.tianocore.devel/15268

Also to follow the idea in the email thread, the patch is to
1. Keep only one copy of full SMRAM ranges in gSmmCorePrivate->SmramRanges,
split record for SmmConfiguration->SmramReservedRegions and SMM Core that
will be marked to be EFI_ALLOCATED in gSmmCorePrivate->SmramRanges.
2. Handle SmmConfiguration->SmramReservedRegions at beginning of, at end of,
in the middle of, or cross multiple SmramRanges.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Star Zeng <star.zeng@intel.com>
Reviewed-by: Jiewen Yao <jiewen.yao@intel.com>

git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@18031 6f19259b-4bc3-4df7-8a09-765794883524

2 files changed, 2 insertions, 5 deletions

diff --git a/MdeModulePkg/Library/PiSmmCoreMemoryAllocationLib/MemoryAllocationLib.c b/MdeModulePkg/Library/PiSmmCoreMemoryAllocationLib/MemoryAllocationLib.c
index 892ba0a040..5e13a3eda2 100644
--- a/MdeModulePkg/Library/PiSmmCoreMemoryAllocationLib/MemoryAllocationLib.c
+++ b/MdeModulePkg/Library/PiSmmCoreMemoryAllocationLib/MemoryAllocationLib.c
@@ -919,11 +919,11 @@ PiSmmCoreMemoryAllocationLibConstructor (
   //

   SmmInitializeMemoryServices (SmmCorePrivate->SmramRangeCount, SmmCorePrivate->SmramRanges);

 

-  mSmmCoreMemoryAllocLibSmramRangeCount = SmmCorePrivate->FullSmramRangeCount;

+  mSmmCoreMemoryAllocLibSmramRangeCount = SmmCorePrivate->SmramRangeCount;

   Size = mSmmCoreMemoryAllocLibSmramRangeCount * sizeof (EFI_SMRAM_DESCRIPTOR);

   mSmmCoreMemoryAllocLibSmramRanges = (EFI_SMRAM_DESCRIPTOR *) AllocatePool (Size);

   ASSERT (mSmmCoreMemoryAllocLibSmramRanges != NULL);

-  CopyMem (mSmmCoreMemoryAllocLibSmramRanges, SmmCorePrivate->FullSmramRanges, Size);

+  CopyMem (mSmmCoreMemoryAllocLibSmramRanges, SmmCorePrivate->SmramRanges, Size);

 

   return EFI_SUCCESS;

 }

diff --git a/MdeModulePkg/Library/PiSmmCoreMemoryAllocationLib/PiSmmCoreMemoryAllocationServices.h b/MdeModulePkg/Library/PiSmmCoreMemoryAllocationLib/PiSmmCoreMemoryAllocationServices.h
index 6ae499b0de..a2b89acf5d 100644
--- a/MdeModulePkg/Library/PiSmmCoreMemoryAllocationLib/PiSmmCoreMemoryAllocationServices.h
+++ b/MdeModulePkg/Library/PiSmmCoreMemoryAllocationLib/PiSmmCoreMemoryAllocationServices.h
@@ -94,9 +94,6 @@ typedef struct {
   EFI_PHYSICAL_ADDRESS            PiSmmCoreImageBase;

   UINT64                          PiSmmCoreImageSize;

   EFI_PHYSICAL_ADDRESS            PiSmmCoreEntryPoint;

-

-  UINTN                           FullSmramRangeCount;

-  EFI_SMRAM_DESCRIPTOR            *FullSmramRanges;

 } SMM_CORE_PRIVATE_DATA;

 

 /**