Commit | Line | Data |
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1da177e4 LT |
1 | /* highmem.c: arch-specific highmem stuff |
2 | * | |
3 | * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved. | |
4 | * Written by David Howells (dhowells@redhat.com) | |
5 | * | |
6 | * This program is free software; you can redistribute it and/or | |
7 | * modify it under the terms of the GNU General Public License | |
8 | * as published by the Free Software Foundation; either version | |
9 | * 2 of the License, or (at your option) any later version. | |
10 | */ | |
11 | #include <linux/highmem.h> | |
40234401 | 12 | #include <linux/module.h> |
1da177e4 LT |
13 | |
14 | void *kmap(struct page *page) | |
15 | { | |
16 | might_sleep(); | |
17 | if (!PageHighMem(page)) | |
18 | return page_address(page); | |
19 | return kmap_high(page); | |
20 | } | |
21 | ||
40234401 DH |
22 | EXPORT_SYMBOL(kmap); |
23 | ||
1da177e4 LT |
24 | void kunmap(struct page *page) |
25 | { | |
26 | if (in_interrupt()) | |
27 | BUG(); | |
28 | if (!PageHighMem(page)) | |
29 | return; | |
30 | kunmap_high(page); | |
31 | } | |
32 | ||
40234401 DH |
33 | EXPORT_SYMBOL(kunmap); |
34 | ||
1da177e4 LT |
35 | struct page *kmap_atomic_to_page(void *ptr) |
36 | { | |
37 | return virt_to_page(ptr); | |
38 | } | |
3e4d3af5 | 39 | |
a24401bc | 40 | void *kmap_atomic(struct page *page) |
3e4d3af5 PZ |
41 | { |
42 | unsigned long paddr; | |
43 | int type; | |
44 | ||
45 | pagefault_disable(); | |
46 | type = kmap_atomic_idx_push(); | |
47 | paddr = page_to_phys(page); | |
48 | ||
49 | switch (type) { | |
50 | /* | |
51 | * The first 4 primary maps are reserved for architecture code | |
52 | */ | |
144cf864 CW |
53 | case 0: return __kmap_atomic_primary(0, paddr, 6); |
54 | case 1: return __kmap_atomic_primary(0, paddr, 7); | |
55 | case 2: return __kmap_atomic_primary(0, paddr, 8); | |
56 | case 3: return __kmap_atomic_primary(0, paddr, 9); | |
57 | case 4: return __kmap_atomic_primary(0, paddr, 10); | |
3e4d3af5 PZ |
58 | |
59 | case 5 ... 5 + NR_TLB_LINES - 1: | |
60 | return __kmap_atomic_secondary(type - 5, paddr); | |
61 | ||
62 | default: | |
63 | BUG(); | |
64 | return NULL; | |
65 | } | |
66 | } | |
a24401bc | 67 | EXPORT_SYMBOL(kmap_atomic); |
3e4d3af5 PZ |
68 | |
69 | void __kunmap_atomic(void *kvaddr) | |
70 | { | |
20273941 | 71 | int type = kmap_atomic_idx(); |
3e4d3af5 | 72 | switch (type) { |
144cf864 CW |
73 | case 0: __kunmap_atomic_primary(0, 6); break; |
74 | case 1: __kunmap_atomic_primary(0, 7); break; | |
75 | case 2: __kunmap_atomic_primary(0, 8); break; | |
76 | case 3: __kunmap_atomic_primary(0, 9); break; | |
77 | case 4: __kunmap_atomic_primary(0, 10); break; | |
3e4d3af5 PZ |
78 | |
79 | case 5 ... 5 + NR_TLB_LINES - 1: | |
80 | __kunmap_atomic_secondary(type - 5, kvaddr); | |
81 | break; | |
82 | ||
83 | default: | |
84 | BUG(); | |
85 | } | |
20273941 | 86 | kmap_atomic_idx_pop(); |
3e4d3af5 PZ |
87 | pagefault_enable(); |
88 | } | |
89 | EXPORT_SYMBOL(__kunmap_atomic); |