| Matt Mackall | e647309 | 2008-02-04 22:29:01 -0800 | [diff] [blame] | 1 | #include <linux/mm.h> |
| 2 | #include <linux/highmem.h> |
| 3 | #include <linux/sched.h> |
| 4 | |
| 5 | static int walk_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end, |
| 6 | const struct mm_walk *walk, void *private) |
| 7 | { |
| 8 | pte_t *pte; |
| 9 | int err = 0; |
| 10 | |
| 11 | pte = pte_offset_map(pmd, addr); |
| 12 | do { |
| 13 | err = walk->pte_entry(pte, addr, addr + PAGE_SIZE, private); |
| 14 | if (err) |
| 15 | break; |
| 16 | } while (pte++, addr += PAGE_SIZE, addr != end); |
| 17 | |
| 18 | pte_unmap(pte); |
| 19 | return err; |
| 20 | } |
| 21 | |
| 22 | static int walk_pmd_range(pud_t *pud, unsigned long addr, unsigned long end, |
| 23 | const struct mm_walk *walk, void *private) |
| 24 | { |
| 25 | pmd_t *pmd; |
| 26 | unsigned long next; |
| 27 | int err = 0; |
| 28 | |
| 29 | pmd = pmd_offset(pud, addr); |
| 30 | do { |
| 31 | next = pmd_addr_end(addr, end); |
| 32 | if (pmd_none_or_clear_bad(pmd)) { |
| 33 | if (walk->pte_hole) |
| 34 | err = walk->pte_hole(addr, next, private); |
| 35 | if (err) |
| 36 | break; |
| 37 | continue; |
| 38 | } |
| 39 | if (walk->pmd_entry) |
| 40 | err = walk->pmd_entry(pmd, addr, next, private); |
| 41 | if (!err && walk->pte_entry) |
| 42 | err = walk_pte_range(pmd, addr, next, walk, private); |
| 43 | if (err) |
| 44 | break; |
| 45 | } while (pmd++, addr = next, addr != end); |
| 46 | |
| 47 | return err; |
| 48 | } |
| 49 | |
| 50 | static int walk_pud_range(pgd_t *pgd, unsigned long addr, unsigned long end, |
| 51 | const struct mm_walk *walk, void *private) |
| 52 | { |
| 53 | pud_t *pud; |
| 54 | unsigned long next; |
| 55 | int err = 0; |
| 56 | |
| 57 | pud = pud_offset(pgd, addr); |
| 58 | do { |
| 59 | next = pud_addr_end(addr, end); |
| 60 | if (pud_none_or_clear_bad(pud)) { |
| 61 | if (walk->pte_hole) |
| 62 | err = walk->pte_hole(addr, next, private); |
| 63 | if (err) |
| 64 | break; |
| 65 | continue; |
| 66 | } |
| 67 | if (walk->pud_entry) |
| 68 | err = walk->pud_entry(pud, addr, next, private); |
| 69 | if (!err && (walk->pmd_entry || walk->pte_entry)) |
| 70 | err = walk_pmd_range(pud, addr, next, walk, private); |
| 71 | if (err) |
| 72 | break; |
| 73 | } while (pud++, addr = next, addr != end); |
| 74 | |
| 75 | return err; |
| 76 | } |
| 77 | |
| 78 | /** |
| 79 | * walk_page_range - walk a memory map's page tables with a callback |
| 80 | * @mm - memory map to walk |
| 81 | * @addr - starting address |
| 82 | * @end - ending address |
| 83 | * @walk - set of callbacks to invoke for each level of the tree |
| 84 | * @private - private data passed to the callback function |
| 85 | * |
| 86 | * Recursively walk the page table for the memory area in a VMA, |
| 87 | * calling supplied callbacks. Callbacks are called in-order (first |
| 88 | * PGD, first PUD, first PMD, first PTE, second PTE... second PMD, |
| 89 | * etc.). If lower-level callbacks are omitted, walking depth is reduced. |
| 90 | * |
| 91 | * Each callback receives an entry pointer, the start and end of the |
| 92 | * associated range, and a caller-supplied private data pointer. |
| 93 | * |
| 94 | * No locks are taken, but the bottom level iterator will map PTE |
| 95 | * directories from highmem if necessary. |
| 96 | * |
| 97 | * If any callback returns a non-zero value, the walk is aborted and |
| 98 | * the return value is propagated back to the caller. Otherwise 0 is returned. |
| 99 | */ |
| 100 | int walk_page_range(const struct mm_struct *mm, |
| 101 | unsigned long addr, unsigned long end, |
| 102 | const struct mm_walk *walk, void *private) |
| 103 | { |
| 104 | pgd_t *pgd; |
| 105 | unsigned long next; |
| 106 | int err = 0; |
| 107 | |
| 108 | if (addr >= end) |
| 109 | return err; |
| 110 | |
| 111 | pgd = pgd_offset(mm, addr); |
| 112 | do { |
| 113 | next = pgd_addr_end(addr, end); |
| 114 | if (pgd_none_or_clear_bad(pgd)) { |
| 115 | if (walk->pte_hole) |
| 116 | err = walk->pte_hole(addr, next, private); |
| 117 | if (err) |
| 118 | break; |
| 119 | continue; |
| 120 | } |
| 121 | if (walk->pgd_entry) |
| 122 | err = walk->pgd_entry(pgd, addr, next, private); |
| 123 | if (!err && |
| 124 | (walk->pud_entry || walk->pmd_entry || walk->pte_entry)) |
| 125 | err = walk_pud_range(pgd, addr, next, walk, private); |
| 126 | if (err) |
| 127 | break; |
| 128 | } while (pgd++, addr = next, addr != end); |
| 129 | |
| 130 | return err; |
| 131 | } |