stos: pmm: Add pageframe descriptor population

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

paw/stos/head/arch/amd64/page.h

@@ -0,0 +1,15 @@
+/*
+ * Copyright (c) 2026, Chloe M.
+ * Provided under the BSD-3 clause.
+ *
+ * Description: Page-related definitions
+ * Author:      Chloe M.
+ */
+
+#ifndef _MACHINE_PAGE_H_
+#define _MACHINE_PAGE_H_ 1
+
+#define PAGESIZE 4096
+#define LOG2_PAGESIZE 12
+
+#endif  /* !_MACHINE_PAGE_H_ */

paw/stos/head/hal/page.h

@@ -0,0 +1,14 @@
+/*
+ * Copyright (c) 2026, Chloe M.
+ * Provided under the BSD-3 clause.
+ *
+ * Description: Page-related definitions
+ * Author:      Chloe M.
+ */
+
+#ifndef _HAL_PAGE_H_
+#define _HAL_PAGE_H_ 1
+
+#include <machine/page.h>
+
+#endif  /* !_HAL_PAGE_H_ */

paw/stos/mm/pmm.c

@@ -9,7 +9,12 @@
 #include <ex/trace.h>
 #include <ke/bpal.h>
 #include <mm/pmm.h>
+#include <mm/vmm.h>
+#include <hal/page.h>
 #include <units.h>
+#include <stdef.h>
+
+#define LOAD_DELAY 128
 
 #define DTRACE(Fmt, ...) \
     TRACE("[ PMM ]: " Fmt, ##__VA_ARGS__)
@@ -20,6 +25,28 @@
         ? TypeTab[(TYPE)]       \
         : "invalid"
 
+/*
+ * Physical frame descriptor
+ *
+ * @Next:  Next PFD in list
+ * @Prev:  Previous PFD in list
+ */
+typedef struct _MM_PFD {
+    struct _MM_PFD *Next;
+    struct _MM_PFD *Prev;
+} MM_PFD;
+
+/*
+ * Page frame descriptor list
+ *
+ * @First:  First entry in list
+ * @Last:   Last entry in list
+ */
+typedef struct {
+    MM_PFD *First;
+    MM_PFD *Last;
+} MM_PFD_LIST;
+
 /*
  * Memory type constant to human readable
  * string table.
@@ -38,6 +65,63 @@ static const char *TypeTab[] = {
 
 /* Globals */
 static USIZE UsableMemory = 0;
+static MM_PFD_LIST PfdList;
+
+/*
+ * Append a page frame descriptor to a page frame descriptor list
+ *
+ * @List: PFD list to append to
+ * @Pfd:  PFD to append
+ */
+static VOID
+MmPfdAppend(MM_PFD_LIST *List, MM_PFD *Pfd)
+{
+    MM_PFD *Last;
+
+    if (List == NULL || Pfd == NULL) {
+        return;
+    }
+
+    if (List->Last == NULL || List->First == NULL) {
+        List->Last = Pfd;
+        List->First = Pfd;
+    } else {
+        Last = List->Last;
+        Pfd->Prev = Last;
+        Last->Next = Pfd;
+        List->Last = Pfd;
+    }
+}
+
+/*
+ * Pop a page frame descriptor from a page frame descriptor list
+ *
+ * @List: Page frame descriptor list to pop from
+ *
+ * Returns NULL if there are no entries left
+ */
+static MM_PFD *
+MmPfdPop(MM_PFD_LIST *List)
+{
+    MM_PFD *Last, *Prev;
+
+    if (List == NULL) {
+        return NULL;
+    }
+
+    Last = List->Last;
+    if (Last == NULL) {
+        return NULL;
+    }
+
+    /* Unlink from the list */
+    Prev = Last->Prev;
+    List->Last = List->Last->Prev;
+    Prev->Next = NULL;
+    List->Last = Prev;
+
+    return Last;
+}
 
 /*
  * Print the units of a size in a pretty format
@@ -61,13 +145,29 @@ MmPrintUnits(USIZE Length, const CHAR *Title)
     }
 }
 
+/*
+ * Display a loading status
+ */
+static VOID
+MmLoadUpdate(VOID)
+{
+    const UCHAR LoadMax = 3;
+    static UCHAR LoadIdx = 0;
+    static CHAR LoadProg[3] = {'/', '-', '\\'};
+
+    TRACE("\x1b[?25l%c \b\b", LoadProg[LoadIdx++]);
+    LoadIdx %= LoadMax;
+}
+
 static VOID
 MmProbeMemory(VOID)
 {
     BPAL_HANDLE BpalHandle;
     MEMMAP_ENTRY Entry;
     UPTR EntryEnd;
-    USIZE Idx;
+    VOID *Vma, *Base;
+    USIZE Idx, Offset;
+    USIZE EntryCount = 0;
     ST_STATUS Status;
 
     KeBpalGetHandle(&BpalHandle);
@@ -85,9 +185,23 @@ MmProbeMemory(VOID)
             continue;
         }
 
+        Base = PMA_TO_VMA(Entry.Base);
+        for (Offset = 0; Offset < Entry.Length; Offset += PAGESIZE) {
+            Vma = PTR_OFFSET(Base, Offset);
+            MmPfdAppend(&PfdList, Vma);
+            EntryCount++;
+
+            /* Display a little loader as this takes awhile */
+            if ((EntryCount & (LOAD_DELAY - 1)) == 0) {
+                MmLoadUpdate();
+            }
+        }
+
         UsableMemory += Entry.Length;
     }
 
+    TRACE("\b\x1b[?25h");
+    DTRACE("%d entries populated\n", EntryCount);
     MmPrintUnits(UsableMemory, "avl");
 }