Compute PTE count per page from entry size

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) */
-    PteCount = ((SIZE_TO_PAGES(33554432) + (MM_PTE_PER_PAGE - 1)) / MM_PTE_PER_PAGE);
-    PagedPoolSize = PteCount * MM_PTE_PER_PAGE * MM_PAGE_SIZE;
+    /* Get the number of PTEs per page and calculate size of paged pool (at least 32MiB) */
+    PtesPerPage = MM::Pte::GetPtesPerPage();
+    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.
  *