--- /dev/null
+/*
+ * Physical memory allocation
+ * Copyright (c) 2001,2003,2004 David H. Hovemeyer <daveho@cs.umd.edu>
+ * Copyright (c) 2003, Jeffrey K. Hollingsworth <hollings@cs.umd.edu>
+ * $Revision: 1.1 $
+ *
+ * This is free software. You are permitted to use,
+ * redistribute, and modify it as specified in the file "COPYING".
+ */
+
+#ifndef GEEKOS_MEM_H
+#define GEEKOS_MEM_H
+
+#include <geekos/ktypes.h>
+#include <geekos/defs.h>
+#include <geekos/list.h>
+#include <geekos/paging.h>
+
+struct Boot_Info;
+
+/*
+ * Page flags
+ */
+#define PAGE_AVAIL 0x0000 /* page is on the freelist */
+#define PAGE_KERN 0x0001 /* page used by kernel code or data */
+#define PAGE_HW 0x0002 /* page used by hardware (e.g., ISA hole) */
+#define PAGE_ALLOCATED 0x0004 /* page is allocated */
+#define PAGE_UNUSED 0x0008 /* page is unused */
+#define PAGE_HEAP 0x0010 /* page is in kernel heap */
+#define PAGE_PAGEABLE 0x0020 /* page can be paged out */
+#define PAGE_LOCKED 0x0040 /* page is taken should not be freed */
+#define PAGE_VM 0x0080 /* page is used by the VM */
+
+
+struct Page;
+
+/*
+ * List datatype for doubly-linked list of Pages.
+ */
+DEFINE_LIST(Page_List, Page);
+
+/*
+ * Each page of physical memory has one of these structures
+ * associated with it, to do allocation and bookkeeping.
+ */
+struct Page {
+ unsigned flags; /* Flags indicating state of page */
+ DEFINE_LINK(Page_List, Page); /* Link fields for Page_List */
+ int clock;
+ ulong_t vaddr; /* User virtual address where page is mapped */
+ pte_t *entry; /* Page table entry referring to the page */
+};
+
+IMPLEMENT_LIST(Page_List, Page);
+
+void Init_Mem(struct Boot_Info* bootInfo);
+void Init_BSS(void);
+void* Alloc_Page(void);
+void* Alloc_Pageable_Page(pte_t *entry, ulong_t vaddr);
+void Free_Page(void* pageAddr);
+
+/*
+ * Determine if given address is a multiple of the page size.
+ */
+static __inline__ bool Is_Page_Multiple(ulong_t addr)
+{
+ return addr == (addr & ~(PAGE_MASK));
+}
+
+/*
+ * Round given address up to a multiple of the page size
+ */
+static __inline__ ulong_t Round_Up_To_Page(ulong_t addr)
+{
+ if ((addr & PAGE_MASK) != 0) {
+ addr &= ~(PAGE_MASK);
+ addr += PAGE_SIZE;
+ }
+ return addr;
+}
+
+/*
+ * Round given address down to a multiple of the page size
+ */
+static __inline__ ulong_t Round_Down_To_Page(ulong_t addr)
+{
+ return addr & (~PAGE_MASK);
+}
+
+/*
+ * Get the index of the page in memory.
+ */
+static __inline__ int Page_Index(ulong_t addr)
+{
+ return (int) (addr >> PAGE_POWER);
+}
+
+
+/*
+ * Get the Page struct associated with given address.
+ */
+static __inline__ struct Page *Get_Page(ulong_t addr)
+{
+ extern struct Page* g_pageList;
+ return &g_pageList[Page_Index(addr)];
+ //return g_pageList + (sizeof(struct Page) * (int)(addr >> PAGE_POWER));
+}
+
+/*
+ * Get the physical address of the memory represented by given Page object.
+ */
+static __inline__ ulong_t Get_Page_Address(struct Page *page)
+{
+ extern struct Page* g_pageList;
+ ulong_t index = page - g_pageList;
+ return index << PAGE_POWER;
+}
+
+#endif /* GEEKOS_MEM_H */