m68k: discontinuous memory support
[linux-2.6.git] / include / asm-m68k / virtconvert.h
1 #ifndef __VIRT_CONVERT__
2 #define __VIRT_CONVERT__
3
4 /*
5  * Macros used for converting between virtual and physical mappings.
6  */
7
8 #ifdef __KERNEL__
9
10 #include <linux/compiler.h>
11 #include <linux/mmzone.h>
12 #include <asm/setup.h>
13 #include <asm/page.h>
14
15 /*
16  * Change virtual addresses to physical addresses and vv.
17  */
18 static inline unsigned long virt_to_phys(void *address)
19 {
20         return __pa(address);
21 }
22
23 static inline void *phys_to_virt(unsigned long address)
24 {
25         return __va(address);
26 }
27
28 /* Permanent address of a page. */
29 #ifdef CONFIG_SINGLE_MEMORY_CHUNK
30 #define page_to_phys(page) \
31         __pa(PAGE_OFFSET + (((page) - pg_data_map[0].node_mem_map) << PAGE_SHIFT))
32 #else
33 #define page_to_phys(_page) ({                                          \
34         struct page *__page = _page;                                    \
35         struct pglist_data *pgdat;                                      \
36         pgdat = pg_data_table[page_to_nid(__page)];                     \
37         page_to_pfn(__page) << PAGE_SHIFT;                              \
38 })
39 #endif
40
41 /*
42  * IO bus memory addresses are 1:1 with the physical address,
43  * except on the PCI bus of the Hades.
44  */
45 #ifdef CONFIG_HADES
46 #define virt_to_bus(a) (virt_to_phys(a) + (MACH_IS_HADES ? 0x80000000 : 0))
47 #define bus_to_virt(a) (phys_to_virt((a) - (MACH_IS_HADES ? 0x80000000 : 0)))
48 #else
49 #define virt_to_bus virt_to_phys
50 #define bus_to_virt phys_to_virt
51 #endif
52
53 #endif
54 #endif