1e6473092SMatt Mackall #include <linux/mm.h> 2e6473092SMatt Mackall #include <linux/highmem.h> 3e6473092SMatt Mackall #include <linux/sched.h> 4d33b9f45SNaoya Horiguchi #include <linux/hugetlb.h> 5e6473092SMatt Mackall 6e6473092SMatt Mackall static int walk_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end, 72165009bSDave Hansen struct mm_walk *walk) 8e6473092SMatt Mackall { 9e6473092SMatt Mackall pte_t *pte; 10e6473092SMatt Mackall int err = 0; 11e6473092SMatt Mackall 12e6473092SMatt Mackall pte = pte_offset_map(pmd, addr); 13556637cdSJohannes Weiner for (;;) { 142165009bSDave Hansen err = walk->pte_entry(pte, addr, addr + PAGE_SIZE, walk); 15e6473092SMatt Mackall if (err) 16e6473092SMatt Mackall break; 17556637cdSJohannes Weiner addr += PAGE_SIZE; 18556637cdSJohannes Weiner if (addr == end) 19556637cdSJohannes Weiner break; 20556637cdSJohannes Weiner pte++; 21556637cdSJohannes Weiner } 22e6473092SMatt Mackall 23e6473092SMatt Mackall pte_unmap(pte); 24e6473092SMatt Mackall return err; 25e6473092SMatt Mackall } 26e6473092SMatt Mackall 27e6473092SMatt Mackall static int walk_pmd_range(pud_t *pud, unsigned long addr, unsigned long end, 282165009bSDave Hansen struct mm_walk *walk) 29e6473092SMatt Mackall { 30e6473092SMatt Mackall pmd_t *pmd; 31e6473092SMatt Mackall unsigned long next; 32e6473092SMatt Mackall int err = 0; 33e6473092SMatt Mackall 34e6473092SMatt Mackall pmd = pmd_offset(pud, addr); 35e6473092SMatt Mackall do { 36e6473092SMatt Mackall next = pmd_addr_end(addr, end); 37e6473092SMatt Mackall if (pmd_none_or_clear_bad(pmd)) { 38e6473092SMatt Mackall if (walk->pte_hole) 392165009bSDave Hansen err = walk->pte_hole(addr, next, walk); 40e6473092SMatt Mackall if (err) 41e6473092SMatt Mackall break; 42e6473092SMatt Mackall continue; 43e6473092SMatt Mackall } 44e6473092SMatt Mackall if (walk->pmd_entry) 452165009bSDave Hansen err = walk->pmd_entry(pmd, addr, next, walk); 46e6473092SMatt Mackall if (!err && walk->pte_entry) 472165009bSDave Hansen err = walk_pte_range(pmd, addr, next, walk); 48e6473092SMatt Mackall if (err) 49e6473092SMatt Mackall break; 50e6473092SMatt Mackall } while (pmd++, addr = next, addr != end); 51e6473092SMatt Mackall 52e6473092SMatt Mackall return err; 53e6473092SMatt Mackall } 54e6473092SMatt Mackall 55e6473092SMatt Mackall static int walk_pud_range(pgd_t *pgd, unsigned long addr, unsigned long end, 562165009bSDave Hansen struct mm_walk *walk) 57e6473092SMatt Mackall { 58e6473092SMatt Mackall pud_t *pud; 59e6473092SMatt Mackall unsigned long next; 60e6473092SMatt Mackall int err = 0; 61e6473092SMatt Mackall 62e6473092SMatt Mackall pud = pud_offset(pgd, addr); 63e6473092SMatt Mackall do { 64e6473092SMatt Mackall next = pud_addr_end(addr, end); 65e6473092SMatt Mackall if (pud_none_or_clear_bad(pud)) { 66e6473092SMatt Mackall if (walk->pte_hole) 672165009bSDave Hansen err = walk->pte_hole(addr, next, walk); 68e6473092SMatt Mackall if (err) 69e6473092SMatt Mackall break; 70e6473092SMatt Mackall continue; 71e6473092SMatt Mackall } 72e6473092SMatt Mackall if (walk->pud_entry) 732165009bSDave Hansen err = walk->pud_entry(pud, addr, next, walk); 74e6473092SMatt Mackall if (!err && (walk->pmd_entry || walk->pte_entry)) 752165009bSDave Hansen err = walk_pmd_range(pud, addr, next, walk); 76e6473092SMatt Mackall if (err) 77e6473092SMatt Mackall break; 78e6473092SMatt Mackall } while (pud++, addr = next, addr != end); 79e6473092SMatt Mackall 80e6473092SMatt Mackall return err; 81e6473092SMatt Mackall } 82e6473092SMatt Mackall 83e6473092SMatt Mackall /** 84e6473092SMatt Mackall * walk_page_range - walk a memory map's page tables with a callback 857682486bSRandy Dunlap * @mm: memory map to walk 867682486bSRandy Dunlap * @addr: starting address 877682486bSRandy Dunlap * @end: ending address 887682486bSRandy Dunlap * @walk: set of callbacks to invoke for each level of the tree 89e6473092SMatt Mackall * 90e6473092SMatt Mackall * Recursively walk the page table for the memory area in a VMA, 91e6473092SMatt Mackall * calling supplied callbacks. Callbacks are called in-order (first 92e6473092SMatt Mackall * PGD, first PUD, first PMD, first PTE, second PTE... second PMD, 93e6473092SMatt Mackall * etc.). If lower-level callbacks are omitted, walking depth is reduced. 94e6473092SMatt Mackall * 952165009bSDave Hansen * Each callback receives an entry pointer and the start and end of the 962165009bSDave Hansen * associated range, and a copy of the original mm_walk for access to 972165009bSDave Hansen * the ->private or ->mm fields. 98e6473092SMatt Mackall * 99e6473092SMatt Mackall * No locks are taken, but the bottom level iterator will map PTE 100e6473092SMatt Mackall * directories from highmem if necessary. 101e6473092SMatt Mackall * 102e6473092SMatt Mackall * If any callback returns a non-zero value, the walk is aborted and 103e6473092SMatt Mackall * the return value is propagated back to the caller. Otherwise 0 is returned. 104e6473092SMatt Mackall */ 1052165009bSDave Hansen int walk_page_range(unsigned long addr, unsigned long end, 1062165009bSDave Hansen struct mm_walk *walk) 107e6473092SMatt Mackall { 108e6473092SMatt Mackall pgd_t *pgd; 109e6473092SMatt Mackall unsigned long next; 110e6473092SMatt Mackall int err = 0; 111d33b9f45SNaoya Horiguchi struct vm_area_struct *vma; 112e6473092SMatt Mackall 113e6473092SMatt Mackall if (addr >= end) 114e6473092SMatt Mackall return err; 115e6473092SMatt Mackall 1162165009bSDave Hansen if (!walk->mm) 1172165009bSDave Hansen return -EINVAL; 1182165009bSDave Hansen 1192165009bSDave Hansen pgd = pgd_offset(walk->mm, addr); 120e6473092SMatt Mackall do { 121e6473092SMatt Mackall next = pgd_addr_end(addr, end); 122d33b9f45SNaoya Horiguchi 123*5dc37642SNaoya Horiguchi /* 124*5dc37642SNaoya Horiguchi * handle hugetlb vma individually because pagetable walk for 125*5dc37642SNaoya Horiguchi * the hugetlb page is dependent on the architecture and 126*5dc37642SNaoya Horiguchi * we can't handled it in the same manner as non-huge pages. 127*5dc37642SNaoya Horiguchi */ 128d33b9f45SNaoya Horiguchi vma = find_vma(walk->mm, addr); 129*5dc37642SNaoya Horiguchi #ifdef CONFIG_HUGETLB_PAGE 130d33b9f45SNaoya Horiguchi if (vma && is_vm_hugetlb_page(vma)) { 131*5dc37642SNaoya Horiguchi pte_t *pte; 132*5dc37642SNaoya Horiguchi struct hstate *hs; 133*5dc37642SNaoya Horiguchi 134d33b9f45SNaoya Horiguchi if (vma->vm_end < next) 135d33b9f45SNaoya Horiguchi next = vma->vm_end; 136*5dc37642SNaoya Horiguchi hs = hstate_vma(vma); 137*5dc37642SNaoya Horiguchi pte = huge_pte_offset(walk->mm, 138*5dc37642SNaoya Horiguchi addr & huge_page_mask(hs)); 139*5dc37642SNaoya Horiguchi if (pte && !huge_pte_none(huge_ptep_get(pte)) 140*5dc37642SNaoya Horiguchi && walk->hugetlb_entry) 141*5dc37642SNaoya Horiguchi err = walk->hugetlb_entry(pte, addr, 142*5dc37642SNaoya Horiguchi next, walk); 143*5dc37642SNaoya Horiguchi if (err) 144*5dc37642SNaoya Horiguchi break; 145d33b9f45SNaoya Horiguchi continue; 146d33b9f45SNaoya Horiguchi } 147*5dc37642SNaoya Horiguchi #endif 148e6473092SMatt Mackall if (pgd_none_or_clear_bad(pgd)) { 149e6473092SMatt Mackall if (walk->pte_hole) 1502165009bSDave Hansen err = walk->pte_hole(addr, next, walk); 151e6473092SMatt Mackall if (err) 152e6473092SMatt Mackall break; 153d33b9f45SNaoya Horiguchi pgd++; 154e6473092SMatt Mackall continue; 155e6473092SMatt Mackall } 156e6473092SMatt Mackall if (walk->pgd_entry) 1572165009bSDave Hansen err = walk->pgd_entry(pgd, addr, next, walk); 158e6473092SMatt Mackall if (!err && 159e6473092SMatt Mackall (walk->pud_entry || walk->pmd_entry || walk->pte_entry)) 1602165009bSDave Hansen err = walk_pud_range(pgd, addr, next, walk); 161e6473092SMatt Mackall if (err) 162e6473092SMatt Mackall break; 163d33b9f45SNaoya Horiguchi pgd++; 164d33b9f45SNaoya Horiguchi } while (addr = next, addr != end); 165e6473092SMatt Mackall 166e6473092SMatt Mackall return err; 167e6473092SMatt Mackall } 168