ptos: mm: Add high-level page mapping interface

Signed-off-by: Chloe M. <chloe@mensia.org>

service/ptos/head/mm/vm.h

@@ -10,6 +10,10 @@
 #define _MM_VM_H_ 1
 
 #include <ke/bpal.h>
+#include <hal/vas.h>
+#include <hal/mmu.h>
+#include <ptapi/ptmm.h>
+#include <ptdef.h>
 
 /*
  * Virtual memory allocation region. This is outside the
@@ -28,4 +32,39 @@
 #define VMA_TO_PMA(VMA) \
     (UPTR)PTR_NOFFSET(VMA, KeBpalLoadBase())
 
+/*
+ * Represents a virtual memory range
+ *
+ * @VirtualBase:    Virtual address base
+ * @PhysicalBase:   Physical address base
+ * @Length:         Length of memory range
+ */
+typedef struct {
+    UPTR VirtualBase;
+    UPTR PhysicalBase;
+    USIZE Length;
+} MM_RANGE;
+
+/*
+ * Unmap a virtual memory range
+ *
+ * @Vas:        Virtual address space to unmap
+ * @Range:      Range to unmap
+ * @PageSize:   Page size to unmap
+ */
+PT_STATUS MmUnmapRange(MMU_VAS *Vas, const MM_RANGE *Range, MMU_PAGESIZE PageSize);
+
+/*
+ * Map a virtual memory range
+ *
+ * @Vas:        Virtual address space to map within
+ * @Range:      Range to map
+ * @Prot:       Protection flags to map with
+ * @PageSize:   Page size to map
+ */
+PT_STATUS MmMapRange(
+    MMU_VAS *Vas, const MM_RANGE *Range,
+    MM_PROT Prot, MMU_PAGESIZE PageSize
+);
+
 #endif  /* !_MM_VM_H_ */

service/ptos/mm/vm.c

@@ -0,0 +1,88 @@
+/*
+ * Copyright (c) 2026, Chloe M.
+ * Provided under the BSD-3 clause.
+ *
+ * Description:  Virtual memory management
+ * Author:       Chloe M.
+ */
+
+#include <mm/vm.h>
+#include <hal/page.h>
+#include <ptdef.h>
+
+/* Use to safely convert page size */
+#define PAGE_SIZE(PS)                \
+    ((PS) >= NELEM(PageSizeTable))   \
+        ? PageSizeTable[PAGESIZE_4K] \
+        : PageSizeTable[(PS)]
+
+/* Page size table */
+static USIZE PageSizeTable[] = {
+    [PAGESIZE_4K] = 0x1000
+};
+
+PT_STATUS MmUnmapRange(MMU_VAS *Vas, const MM_RANGE *Range, MMU_PAGESIZE PageSize)
+{
+    PT_STATUS Status;
+    UPTR Off = 0;
+    UPTR VirtualBase;
+    USIZE Gran;
+
+    if (Vas == NULL || Range == NULL) {
+        return STATUS_INVALID_PARAM;
+    }
+
+    /* Align down the base addresses */
+    VirtualBase = ALIGN_DOWN(Range->VirtualBase, PAGESIZE);
+    Gran = PAGE_SIZE(PageSize);
+
+    for (Off = 0; Off < Range->Length; Off += Gran) {
+        Status = HalMmuUnmapPage(
+            Vas,
+            VirtualBase + Off,
+            PageSize
+        );
+
+        if (PT_ERROR(Status)) {
+            return Status;
+        }
+    }
+
+    return STATUS_SUCCESS;
+}
+
+PT_STATUS
+MmMapRange(MMU_VAS *Vas, const MM_RANGE *Range, MM_PROT Prot, MMU_PAGESIZE PageSize)
+{
+    PT_STATUS Status;
+    UPTR Off = 0;
+    UPTR VirtualBase;
+    UPTR PhysicalBase;
+    USIZE Gran;
+
+    if (Vas == NULL || Range == NULL) {
+        return STATUS_INVALID_PARAM;
+    }
+
+    /* Align down the base addresses */
+    VirtualBase = ALIGN_DOWN(Range->VirtualBase, PAGESIZE);
+    PhysicalBase = ALIGN_DOWN(Range->PhysicalBase, PAGESIZE);
+    Gran = PAGE_SIZE(PageSize);
+
+    for (Off = 0; Off < Range->Length; Off += Gran) {
+        Status = HalMmuMapPage(
+            Vas,
+            VirtualBase + Off,
+            PhysicalBase + Off,
+            Prot,
+            PageSize
+        );
+
+        if (PT_ERROR(Status)) {
+            MmUnmapRange(Vas, Range, PageSize);
+            return Status;
+        }
+    }
+
+    return STATUS_SUCCESS;
+}