projects / deliverable / linux.git / blame
| Commit | Line | Data |
|---|---|---|
| 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 PZ |
39 | |
| 40 | void *__kmap_atomic(struct page *page) | |
| 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 | */ | |
| 53 | case 0: return __kmap_atomic_primary(4, paddr, 6); | |
| 54 | case 1: return __kmap_atomic_primary(5, paddr, 7); | |
| 55 | case 2: return __kmap_atomic_primary(6, paddr, 8); | |
| 56 | case 3: return __kmap_atomic_primary(7, paddr, 9); | |
| 57 | case 4: return __kmap_atomic_primary(8, paddr, 10); | |
| 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 | } | |
| 67 | EXPORT_SYMBOL(__kmap_atomic); | |
| 68 | ||
| 69 | void __kunmap_atomic(void *kvaddr) | |
| 70 | { | |
| 20273941 | 71 | int type = kmap_atomic_idx(); |
| 3e4d3af5 PZ |
72 | switch (type) { |
| 73 | case 0: __kunmap_atomic_primary(4, 6); break; | |
| 74 | case 1: __kunmap_atomic_primary(5, 7); break; | |
| 75 | case 2: __kunmap_atomic_primary(6, 8); break; | |
| 76 | case 3: __kunmap_atomic_primary(7, 9); break; | |
| 77 | case 4: __kunmap_atomic_primary(8, 10); break; | |
| 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); |