From 2f3c4c9dc6699d8e5d6967f1a7f953071197d478 Mon Sep 17 00:00:00 2001
From: Mikhail Krichanov <mikhailkrichanov@gmail.com>
Date: Thu, 19 Dec 2024 13:24:32 +0300
Subject: [PATCH] Ring3: Added MakeUserPageTableTemplate() for ARM.

---
 ArmPkg/Include/Chipset/ArmV7Mmu.h             |  6 +--
 ArmPkg/Library/ArmMmuLib/Arm/ArmMmuLibCore.c  | 48 +++++++++++++++++--
 .../Core/Dxe/SysCall/ARM/InitializeARM.c      | 29 +++++++++++
 3 files changed, 75 insertions(+), 8 deletions(-)

diff --git a/ArmPkg/Include/Chipset/ArmV7Mmu.h b/ArmPkg/Include/Chipset/ArmV7Mmu.h
index 959c29f2d5..d0086246a4 100644
--- a/ArmPkg/Include/Chipset/ArmV7Mmu.h
+++ b/ArmPkg/Include/Chipset/ArmV7Mmu.h
@@ -162,8 +162,7 @@
                                         TT_DESCRIPTOR_SECTION_NG_GLOBAL    | \
                                         TT_DESCRIPTOR_SECTION_S_SHARED     | \
                                         TT_DESCRIPTOR_SECTION_DOMAIN(0)    | \
-                                        TT_DESCRIPTOR_SECTION_AP_NO_RW     | \
-                                        TT_DESCRIPTOR_SECTION_AF)
+                                        TT_DESCRIPTOR_SECTION_AP_NO_RW)
 
 #define TT_DESCRIPTOR_SECTION_WRITE_BACK  (TT_DESCRIPTOR_SECTION_DEFAULT | \
                                            TT_DESCRIPTOR_SECTION_CACHE_POLICY_WRITE_BACK_ALLOC)
@@ -179,8 +178,7 @@
 
 #define TT_DESCRIPTOR_PAGE_DEFAULT  (TT_DESCRIPTOR_PAGE_TYPE_PAGE | \
                                      TT_DESCRIPTOR_PAGE_NG_GLOBAL | \
-                                     TT_DESCRIPTOR_PAGE_AP_NO_RW  | \
-                                     TT_DESCRIPTOR_PAGE_AF)
+                                     TT_DESCRIPTOR_PAGE_AP_NO_RW)
 
 #define TT_DESCRIPTOR_PAGE_WRITE_BACK     (TT_DESCRIPTOR_PAGE_DEFAULT  | \
                                            TT_DESCRIPTOR_PAGE_S_SHARED | \
diff --git a/ArmPkg/Library/ArmMmuLib/Arm/ArmMmuLibCore.c b/ArmPkg/Library/ArmMmuLib/Arm/ArmMmuLibCore.c
index 55ceeaae27..dd03ffdbd7 100644
--- a/ArmPkg/Library/ArmMmuLib/Arm/ArmMmuLibCore.c
+++ b/ArmPkg/Library/ArmMmuLib/Arm/ArmMmuLibCore.c
@@ -86,7 +86,8 @@ PopulateLevel2PageTable (
   IN UINT32                        *SectionEntry,
   IN UINT32                        PhysicalBase,
   IN UINT32                        RemainLength,
-  IN ARM_MEMORY_REGION_ATTRIBUTES  Attributes
+  IN ARM_MEMORY_REGION_ATTRIBUTES  Attributes,
+  IN BOOLEAN                       UserTable
   )
 {
   UINT32  *PageEntry;
@@ -132,6 +133,10 @@ PopulateLevel2PageTable (
     PageAttributes &= ~TT_DESCRIPTOR_PAGE_S_SHARED;
   }
 
+  if (!UserTable) {
+    PageAttributes |= TT_DESCRIPTOR_PAGE_AF;
+  }
+
   // Check if the Section Entry has already been populated. Otherwise attach a
   // Level 2 Translation Table to it
   if (*SectionEntry != 0) {
@@ -220,7 +225,8 @@ STATIC
 VOID
 FillTranslationTable (
   IN  UINT32                        *TranslationTable,
-  IN  ARM_MEMORY_REGION_DESCRIPTOR  *MemoryRegion
+  IN  ARM_MEMORY_REGION_DESCRIPTOR  *MemoryRegion,
+  IN  BOOLEAN                       UserTable
   )
 {
   UINT32  *SectionEntry;
@@ -272,6 +278,10 @@ FillTranslationTable (
     Attributes &= ~TT_DESCRIPTOR_SECTION_S_SHARED;
   }
 
+  if (!UserTable) {
+    Attributes |= TT_DESCRIPTOR_SECTION_AF;
+  }
+
   // Get the first section entry for this mapping
   SectionEntry = TRANSLATION_TABLE_ENTRY_FOR_VIRTUAL_ADDRESS (TranslationTable, MemoryRegion->VirtualBase);
 
@@ -307,7 +317,8 @@ FillTranslationTable (
         SectionEntry,
         PhysicalBase,
         PageMapLength,
-        MemoryRegion->Attributes
+        MemoryRegion->Attributes,
+        UserTable
         );
 
       //
@@ -364,7 +375,7 @@ ArmConfigureMmu (
   ZeroMem (TranslationTable, TRANSLATION_TABLE_SECTION_SIZE);
 
   while (MemoryTable->Length != 0) {
-    FillTranslationTable (TranslationTable, MemoryTable);
+    FillTranslationTable (TranslationTable, MemoryTable, FALSE);
     MemoryTable++;
   }
 
@@ -424,3 +435,32 @@ ArmConfigureMmu (
   ArmEnableMmu ();
   return RETURN_SUCCESS;
 }
+
+EFI_STATUS
+EFIAPI
+ArmMakeUserPageTableTemplate (
+  IN  ARM_MEMORY_REGION_DESCRIPTOR  *MemoryTable,
+  OUT UINTN                         *TranslationTableBase,
+  OUT UINTN                         *TranslationTableSize
+  )
+{
+  VOID  *TranslationTable;
+
+  TranslationTable = AllocateAlignedPages (
+                       EFI_SIZE_TO_PAGES (TRANSLATION_TABLE_SECTION_SIZE),
+                       TRANSLATION_TABLE_SECTION_ALIGNMENT
+                       );
+  if (TranslationTable == NULL) {
+    return EFI_OUT_OF_RESOURCES;
+  }
+
+  ZeroMem (TranslationTable, TRANSLATION_TABLE_SECTION_SIZE);
+
+  FillTranslationTable (TranslationTable, MemoryTable, TRUE);
+
+  *TranslationTableBase = (UINTN)TranslationTable;
+  *TranslationTableSize = TRANSLATION_TABLE_SECTION_SIZE;
+
+  return EFI_SUCCESS;
+
+}
diff --git a/MdeModulePkg/Core/Dxe/SysCall/ARM/InitializeARM.c b/MdeModulePkg/Core/Dxe/SysCall/ARM/InitializeARM.c
index 7f68d92fb7..b090af890d 100644
--- a/MdeModulePkg/Core/Dxe/SysCall/ARM/InitializeARM.c
+++ b/MdeModulePkg/Core/Dxe/SysCall/ARM/InitializeARM.c
@@ -6,6 +6,7 @@
 **/
 
 #include <Library/ArmLib.h>
+#include <Library/ArmMmuLib.h>
 #include <Library/DefaultExceptionHandlerLib.h>
 
 #include "DxeMain.h"
@@ -97,6 +98,34 @@ SysCallBootService (
   return Status;
 }
 
+VOID
+EFIAPI
+MakeUserPageTableTemplate (
+  OUT UINTN  *UserPageTableTemplate,
+  OUT UINTN  *UserPageTableTemplateSize
+  )
+{
+  ARM_MEMORY_REGION_DESCRIPTOR  Descriptor;
+  VOID                          *MemorySizeHob;
+
+  MemorySizeHob = GetFirstGuidHob (&gArmVirtSystemMemorySizeGuid);
+  ASSERT (MemorySizeHob != NULL);
+  if (MemorySizeHob == NULL) {
+    return;
+  }
+
+  Descriptor.PhysicalBase = PcdGet64 (PcdSystemMemoryBase);
+  Descriptor.VirtualBase  = Descriptor.PhysicalBase;
+  Descriptor.Length       = *(UINT64 *)GET_GUID_HOB_DATA (MemorySizeHob);
+  Descriptor.Attributes   = ARM_MEMORY_REGION_ATTRIBUTE_WRITE_BACK;
+
+  ArmMakeUserPageTableTemplate (
+    &Descriptor,
+    UserPageTableTemplate,
+    UserPageTableTemplateSize
+    );
+}
+
 VOID
 EFIAPI
 InitializeMsr (