diff options
Diffstat (limited to 'UefiCpuPkg/Library/CpuPageTableLib/CpuPageTableMap.c')
| -rw-r--r-- | UefiCpuPkg/Library/CpuPageTableLib/CpuPageTableMap.c | 85 |
1 files changed, 32 insertions, 53 deletions
diff --git a/UefiCpuPkg/Library/CpuPageTableLib/CpuPageTableMap.c b/UefiCpuPkg/Library/CpuPageTableLib/CpuPageTableMap.c index 11cca8ccbc..0d576ce39a 100644 --- a/UefiCpuPkg/Library/CpuPageTableLib/CpuPageTableMap.c +++ b/UefiCpuPkg/Library/CpuPageTableLib/CpuPageTableMap.c @@ -351,68 +351,45 @@ PageTableLibMapInLevel ( // ParentPagingEntry ONLY is deferenced for checking Present and MustBeOne bits
// when Modify is FALSE.
//
-
- if (ParentPagingEntry->Pce.Present == 0) {
- //
- // [LinearAddress, LinearAddress + Length] contains non-present range.
- //
- Status = IsAttributesAndMaskValidForNonPresentEntry (Attribute, Mask);
- if (RETURN_ERROR (Status)) {
- return Status;
- }
-
- //
- // Check the attribute in ParentPagingEntry is equal to attribute calculated by input Attribue and Mask.
- //
- PleBAttribute.Uint64 = PageTableLibGetPleBMapAttribute (&ParentPagingEntry->PleB, ParentAttribute);
- if ((IA32_MAP_ATTRIBUTE_ATTRIBUTES (&PleBAttribute) & IA32_MAP_ATTRIBUTE_ATTRIBUTES (Mask))
- == (IA32_MAP_ATTRIBUTE_ATTRIBUTES (Attribute) & IA32_MAP_ATTRIBUTE_ATTRIBUTES (Mask)))
- {
- return RETURN_SUCCESS;
- }
-
+ if ((ParentPagingEntry->Pce.Present == 0) || IsPle (ParentPagingEntry, Level + 1)) {
//
- // The parent entry is CR3 or PML5E/PML4E/PDPTE/PDE.
+ // When ParentPagingEntry is non-present, parent entry is CR3 or PML5E/PML4E/PDPTE/PDE.
// It does NOT point to an existing page directory.
+ // When ParentPagingEntry is present, parent entry is leaf PDPTE_1G or PDE_2M. Split to 2M or 4K pages.
+ // Note: it's impossible the parent entry is a PTE_4K.
//
- ASSERT (Buffer == NULL || *BufferSize >= SIZE_4KB);
- CreateNew = TRUE;
- *BufferSize -= SIZE_4KB;
-
- if (Modify) {
- ParentPagingEntry->Uintn = (UINTN)Buffer + *BufferSize;
- ZeroMem ((VOID *)ParentPagingEntry->Uintn, SIZE_4KB);
- //
- // Set default attribute bits for PML5E/PML4E/PDPTE/PDE.
- //
- PageTableLibSetPnle (&ParentPagingEntry->Pnle, &NopAttribute, &AllOneMask);
- } else {
+ PleBAttribute.Uint64 = PageTableLibGetPleBMapAttribute (&ParentPagingEntry->PleB, ParentAttribute);
+ if (ParentPagingEntry->Pce.Present == 0) {
//
- // Just make sure Present and MustBeZero (PageSize) bits are accurate.
+ // [LinearAddress, LinearAddress + Length] contains non-present range.
//
+ Status = IsAttributesAndMaskValidForNonPresentEntry (Attribute, Mask);
+ if (RETURN_ERROR (Status)) {
+ return Status;
+ }
+
OneOfPagingEntry.Pnle.Uint64 = 0;
+ } else {
+ PageTableLibSetPle (Level, &OneOfPagingEntry, 0, &PleBAttribute, &AllOneMask);
}
- } else if (IsPle (ParentPagingEntry, Level + 1)) {
- //
- // The parent entry is a PDPTE_1G or PDE_2M. Split to 2M or 4K pages.
- // Note: it's impossible the parent entry is a PTE_4K.
- //
+
//
- // Use NOP attributes as the attribute of grand-parents because CPU will consider
- // the actual attributes of grand-parents when determing the memory type.
+ // Check if the attribute, the physical address calculated by ParentPagingEntry is equal to
+ // the attribute, the physical address calculated by input Attribue and Mask.
//
- PleBAttribute.Uint64 = PageTableLibGetPleBMapAttribute (&ParentPagingEntry->PleB, ParentAttribute);
if ((IA32_MAP_ATTRIBUTE_ATTRIBUTES (&PleBAttribute) & IA32_MAP_ATTRIBUTE_ATTRIBUTES (Mask))
== (IA32_MAP_ATTRIBUTE_ATTRIBUTES (Attribute) & IA32_MAP_ATTRIBUTE_ATTRIBUTES (Mask)))
{
- //
- // This function is called when the memory length is less than the region length of the parent level.
- // No need to split the page when the attributes equal.
- //
if ((Mask->Bits.PageTableBaseAddressLow == 0) && (Mask->Bits.PageTableBaseAddressHigh == 0)) {
return RETURN_SUCCESS;
}
+ //
+ // Non-present entry won't reach there since:
+ // 1.When map non-present entry to present, the attribute must be different.
+ // 2.When still map non-present entry to non-present, PageTableBaseAddressLow and High in Mask must be 0.
+ //
+ ASSERT (ParentPagingEntry->Pce.Present == 1);
PhysicalAddrInEntry = IA32_MAP_ATTRIBUTE_PAGE_TABLE_BASE_ADDRESS (&PleBAttribute) + MultU64x32 (RegionLength, (UINT32)PagingEntryIndex);
PhysicalAddrInAttr = (IA32_MAP_ATTRIBUTE_PAGE_TABLE_BASE_ADDRESS (Attribute) + Offset) & (~RegionMask);
if (PhysicalAddrInEntry == PhysicalAddrInAttr) {
@@ -423,17 +400,19 @@ PageTableLibMapInLevel ( ASSERT (Buffer == NULL || *BufferSize >= SIZE_4KB);
CreateNew = TRUE;
*BufferSize -= SIZE_4KB;
- PageTableLibSetPle (Level, &OneOfPagingEntry, 0, &PleBAttribute, &AllOneMask);
+
if (Modify) {
- //
- // Create 512 child-level entries that map to 2M/4K.
- //
PagingEntry = (IA32_PAGING_ENTRY *)((UINTN)Buffer + *BufferSize);
ZeroMem (PagingEntry, SIZE_4KB);
- for (SubOffset = 0, Index = 0; Index < 512; Index++) {
- PagingEntry[Index].Uint64 = OneOfPagingEntry.Uint64 + SubOffset;
- SubOffset += RegionLength;
+ if (ParentPagingEntry->Pce.Present) {
+ //
+ // Create 512 child-level entries that map to 2M/4K.
+ //
+ for (SubOffset = 0, Index = 0; Index < 512; Index++) {
+ PagingEntry[Index].Uint64 = OneOfPagingEntry.Uint64 + SubOffset;
+ SubOffset += RegionLength;
+ }
}
//
|