Compute PTE count per page from entry size

sdk/xtdk/amd64/mmtypes.h

@@ -43,12 +43,6 @@
 #define MM_PXI_SHIFT                               39
 #define MM_P5I_SHIFT                               48
 
-/* Number of PTEs per page */
-#define MM_PTE_PER_PAGE                            512
-#define MM_PDE_PER_PAGE                            512
-#define MM_PPE_PER_PAGE                            512
-#define MM_PXE_PER_PAGE                            512
-
 /* PTE state flags */
 #define MM_PTE_VALID                               0x0000000000000001ULL
 #define MM_PTE_ACCESSED                            0x0000000000000020ULL

xtoskrnl/includes/mm/pte.hh

@@ -18,6 +18,7 @@ namespace MM
     class Pte
     {
         public:
+            STATIC XTAPI ULONG GetPtesPerPage(VOID);
             STATIC XTAPI VOID MapP5E(PVOID StartAddress,
                                      PVOID EndAddress,
                                      PMMP5E TemplateP5e);

xtoskrnl/mm/mmgr.cc

@@ -38,10 +38,12 @@ MM::Manager::InitializeMemoryLayout(VOID)
 {
     ULONG_PTR PagedPoolSize, PteCount;
     PFN_NUMBER PfnDatabaseSize;
+    ULONG PtesPerPage;
 
-    /* Calculate size of paged pool (at least 32MiB) */
+    /* Get the number of PTEs per page and calculate size of paged pool (at least 32MiB) */
-    PteCount = ((SIZE_TO_PAGES(33554432) + (MM_PTE_PER_PAGE - 1)) / MM_PTE_PER_PAGE);
+    PtesPerPage = MM::Pte::GetPtesPerPage();
-    PagedPoolSize = PteCount * MM_PTE_PER_PAGE * MM_PAGE_SIZE;
+    PteCount = ((SIZE_TO_PAGES(33554432) + (PtesPerPage - 1)) / PtesPerPage);
+    PagedPoolSize = PteCount * PtesPerPage * MM_PAGE_SIZE;
 
     /* Retrieve the PFN database size */
     PfnDatabaseSize = MM::Pfn::GetPfnDatabaseSize();

xtoskrnl/mm/pte.cc

@@ -9,6 +9,21 @@
 #include <xtos.hh>
 
 
+/**
+ * Calculates the number of Page Table Entries (PTEs) that fit within a single page.
+ *
+ * @return This routine returns the number of PTEs per page.
+ *
+ * @since XT 1.0
+ */
+XTAPI
+ULONG
+MM::Pte::GetPtesPerPage(VOID)
+{
+    /* Calculate and return the number of PTEs per page */
+    return MM_PAGE_SIZE / MM::Paging::GetPteSize();
+}
+
 /**
  * Maps a range of virtual addresses at the P5E (PML5) level.
  *