Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * highmem.h: virtual kernel memory mappings for high memory | |
3 | * | |
4 | * Used in CONFIG_HIGHMEM systems for memory pages which | |
5 | * are not addressable by direct kernel virtual addresses. | |
6 | * | |
7 | * Copyright (C) 1999 Gerhard Wichert, Siemens AG | |
8 | * Gerhard.Wichert@pdb.siemens.de | |
9 | * | |
10 | * | |
11 | * Redesigned the x86 32-bit VM architecture to deal with | |
12 | * up to 16 Terabyte physical memory. With current x86 CPUs | |
13 | * we now support up to 64 Gigabytes physical RAM. | |
14 | * | |
15 | * Copyright (C) 1999 Ingo Molnar <mingo@redhat.com> | |
16 | */ | |
17 | #ifndef _ASM_HIGHMEM_H | |
18 | #define _ASM_HIGHMEM_H | |
19 | ||
20 | #ifdef __KERNEL__ | |
21 | ||
34ae8e36 | 22 | #include <linux/bug.h> |
1da177e4 | 23 | #include <linux/interrupt.h> |
ad76fb6b | 24 | #include <linux/uaccess.h> |
34ae8e36 | 25 | #include <asm/cpu-features.h> |
1da177e4 LT |
26 | #include <asm/kmap_types.h> |
27 | ||
28 | /* undef for production */ | |
29 | #define HIGHMEM_DEBUG 1 | |
30 | ||
31 | /* declarations for highmem.c */ | |
32 | extern unsigned long highstart_pfn, highend_pfn; | |
33 | ||
1da177e4 LT |
34 | extern pte_t *pkmap_page_table; |
35 | ||
36 | /* | |
37 | * Right now we initialize only a single pte table. It can be extended | |
38 | * easily, subsequent pte tables have to be allocated in one physical | |
39 | * chunk of RAM. | |
40 | */ | |
1da177e4 LT |
41 | #define LAST_PKMAP 1024 |
42 | #define LAST_PKMAP_MASK (LAST_PKMAP-1) | |
70342287 RB |
43 | #define PKMAP_NR(virt) ((virt-PKMAP_BASE) >> PAGE_SHIFT) |
44 | #define PKMAP_ADDR(nr) (PKMAP_BASE + ((nr) << PAGE_SHIFT)) | |
1da177e4 LT |
45 | |
46 | extern void * kmap_high(struct page *page); | |
47 | extern void kunmap_high(struct page *page); | |
48 | ||
3e4d3af5 PZ |
49 | extern void *kmap(struct page *page); |
50 | extern void kunmap(struct page *page); | |
a24401bc | 51 | extern void *kmap_atomic(struct page *page); |
3e4d3af5 PZ |
52 | extern void __kunmap_atomic(void *kvaddr); |
53 | extern void *kmap_atomic_pfn(unsigned long pfn); | |
1da177e4 | 54 | |
34ae8e36 | 55 | #define flush_cache_kmaps() BUG_ON(cpu_has_dc_aliases) |
1da177e4 | 56 | |
bb86bf28 RB |
57 | extern void kmap_init(void); |
58 | ||
59 | #define kmap_prot PAGE_KERNEL | |
60 | ||
1da177e4 LT |
61 | #endif /* __KERNEL__ */ |
62 | ||
63 | #endif /* _ASM_HIGHMEM_H */ |