diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /include/asm-mips/highmem.h |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'include/asm-mips/highmem.h')
-rw-r--r-- | include/asm-mips/highmem.h | 103 |
1 files changed, 103 insertions, 0 deletions
diff --git a/include/asm-mips/highmem.h b/include/asm-mips/highmem.h new file mode 100644 index 000000000000..f49930d947d4 --- /dev/null +++ b/include/asm-mips/highmem.h | |||
@@ -0,0 +1,103 @@ | |||
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 | |||
22 | #include <linux/config.h> | ||
23 | #include <linux/init.h> | ||
24 | #include <linux/interrupt.h> | ||
25 | #include <asm/kmap_types.h> | ||
26 | |||
27 | /* undef for production */ | ||
28 | #define HIGHMEM_DEBUG 1 | ||
29 | |||
30 | /* declarations for highmem.c */ | ||
31 | extern unsigned long highstart_pfn, highend_pfn; | ||
32 | |||
33 | extern pte_t *kmap_pte; | ||
34 | extern pgprot_t kmap_prot; | ||
35 | extern pte_t *pkmap_page_table; | ||
36 | |||
37 | /* | ||
38 | * Right now we initialize only a single pte table. It can be extended | ||
39 | * easily, subsequent pte tables have to be allocated in one physical | ||
40 | * chunk of RAM. | ||
41 | */ | ||
42 | #define PKMAP_BASE (0xfe000000UL) | ||
43 | #define LAST_PKMAP 1024 | ||
44 | #define LAST_PKMAP_MASK (LAST_PKMAP-1) | ||
45 | #define PKMAP_NR(virt) ((virt-PKMAP_BASE) >> PAGE_SHIFT) | ||
46 | #define PKMAP_ADDR(nr) (PKMAP_BASE + ((nr) << PAGE_SHIFT)) | ||
47 | |||
48 | extern void * kmap_high(struct page *page); | ||
49 | extern void kunmap_high(struct page *page); | ||
50 | |||
51 | /* | ||
52 | * CONFIG_LIMITED_DMA is for systems with DMA limitations such as Momentum's | ||
53 | * Jaguar ATX. This option exploits the highmem code in the kernel so is | ||
54 | * always enabled together with CONFIG_HIGHMEM but at this time doesn't | ||
55 | * actually add highmem functionality. | ||
56 | */ | ||
57 | |||
58 | #ifdef CONFIG_LIMITED_DMA | ||
59 | |||
60 | /* | ||
61 | * These are the default functions for the no-highmem case from | ||
62 | * <linux/highmem.h> | ||
63 | */ | ||
64 | static inline void *kmap(struct page *page) | ||
65 | { | ||
66 | might_sleep(); | ||
67 | return page_address(page); | ||
68 | } | ||
69 | |||
70 | #define kunmap(page) do { (void) (page); } while (0) | ||
71 | |||
72 | static inline void *kmap_atomic(struct page *page, enum km_type type) | ||
73 | { | ||
74 | return page_address(page); | ||
75 | } | ||
76 | |||
77 | static inline void kunmap_atomic(void *kvaddr, enum km_type type) { } | ||
78 | |||
79 | #define kmap_atomic_to_page(ptr) virt_to_page(ptr) | ||
80 | |||
81 | #define flush_cache_kmaps() do { } while (0) | ||
82 | |||
83 | #else /* LIMITED_DMA */ | ||
84 | |||
85 | extern void *__kmap(struct page *page); | ||
86 | extern void __kunmap(struct page *page); | ||
87 | extern void *__kmap_atomic(struct page *page, enum km_type type); | ||
88 | extern void __kunmap_atomic(void *kvaddr, enum km_type type); | ||
89 | extern struct page *__kmap_atomic_to_page(void *ptr); | ||
90 | |||
91 | #define kmap __kmap | ||
92 | #define kunmap __kunmap | ||
93 | #define kmap_atomic __kmap_atomic | ||
94 | #define kunmap_atomic __kunmap_atomic | ||
95 | #define kmap_atomic_to_page __kmap_atomic_to_page | ||
96 | |||
97 | #define flush_cache_kmaps() flush_cache_all() | ||
98 | |||
99 | #endif /* LIMITED_DMA */ | ||
100 | |||
101 | #endif /* __KERNEL__ */ | ||
102 | |||
103 | #endif /* _ASM_HIGHMEM_H */ | ||