diff options
| -rw-r--r-- | mm/mincore.c | 171 |
1 files changed, 97 insertions, 74 deletions
diff --git a/mm/mincore.c b/mm/mincore.c index 1f6574c5167b..a0c4c10bbab7 100644 --- a/mm/mincore.c +++ b/mm/mincore.c @@ -19,6 +19,42 @@ #include <asm/uaccess.h> #include <asm/pgtable.h> +static void mincore_hugetlb_page_range(struct vm_area_struct *vma, + unsigned long addr, unsigned long nr, + unsigned char *vec) +{ +#ifdef CONFIG_HUGETLB_PAGE + struct hstate *h; + int i; + + i = 0; + h = hstate_vma(vma); + while (1) { + unsigned char present; + pte_t *ptep; + /* + * Huge pages are always in RAM for now, but + * theoretically it needs to be checked. + */ + ptep = huge_pte_offset(current->mm, + addr & huge_page_mask(h)); + present = ptep && !huge_pte_none(huge_ptep_get(ptep)); + while (1) { + vec[i++] = present; + addr += PAGE_SIZE; + /* reach buffer limit */ + if (i == nr) + return; + /* check hugepage border */ + if (!(addr & ~huge_page_mask(h))) + break; + } + } +#else + BUG(); +#endif +} + /* * Later we can get more picky about what "in core" means precisely. * For now, simply check to see if the page is in the page cache, @@ -49,6 +85,64 @@ static unsigned char mincore_page(struct address_space *mapping, pgoff_t pgoff) return present; } +static void mincore_unmapped_range(struct vm_area_struct *vma, + unsigned long addr, unsigned long nr, + unsigned char *vec) +{ + int i; + + if (vma->vm_file) { + pgoff_t pgoff; + + pgoff = linear_page_index(vma, addr); + for (i = 0; i < nr; i++, pgoff++) + vec[i] = mincore_page(vma->vm_file->f_mapping, pgoff); + } else { + for (i = 0; i < nr; i++) + vec[i] = 0; + } +} + +static void mincore_pte_range(struct vm_area_struct *vma, pmd_t *pmd, + unsigned long addr, unsigned long nr, + unsigned char *vec) +{ + spinlock_t *ptl; + pte_t *ptep; + int i; + + ptep = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); + for (i = 0; i < nr; i++, ptep++, addr += PAGE_SIZE) { + pte_t pte = *ptep; + pgoff_t pgoff; + + if (pte_none(pte)) + mincore_unmapped_range(vma, addr, 1, vec); + else if (pte_present(pte)) + vec[i] = 1; + else if (pte_file(pte)) { + pgoff = pte_to_pgoff(pte); + vec[i] = mincore_page(vma->vm_file->f_mapping, pgoff); + } else { /* pte is a swap entry */ + swp_entry_t entry = pte_to_swp_entry(pte); + + if (is_migration_entry(entry)) { + /* migration entries are always uptodate */ + vec[i] = 1; + } else { +#ifdef CONFIG_SWAP + pgoff = entry.val; + vec[i] = mincore_page(&swapper_space, pgoff); +#else + WARN_ON(1); + vec[i] = 1; +#endif + } + } + } + pte_unmap_unlock(ptep - 1, ptl); +} + /* * Do a chunk of "sys_mincore()". We've already checked * all the arguments, we hold the mmap semaphore: we should @@ -59,11 +153,7 @@ static long do_mincore(unsigned long addr, unsigned long pages, unsigned char *v pgd_t *pgd; pud_t *pud; pmd_t *pmd; - pte_t *ptep; - spinlock_t *ptl; unsigned long nr; - int i; - pgoff_t pgoff; struct vm_area_struct *vma; vma = find_vma(current->mm, addr); @@ -72,35 +162,10 @@ static long do_mincore(unsigned long addr, unsigned long pages, unsigned char *v nr = min(pages, (vma->vm_end - addr) >> PAGE_SHIFT); -#ifdef CONFIG_HUGETLB_PAGE if (is_vm_hugetlb_page(vma)) { - struct hstate *h; - - i = 0; - h = hstate_vma(vma); - while (1) { - unsigned char present; - /* - * Huge pages are always in RAM for now, but - * theoretically it needs to be checked. - */ - ptep = huge_pte_offset(current->mm, - addr & huge_page_mask(h)); - present = ptep && !huge_pte_none(huge_ptep_get(ptep)); - while (1) { - vec[i++] = present; - addr += PAGE_SIZE; - /* reach buffer limit */ - if (i == nr) - return nr; - /* check hugepage border */ - if (!(addr & ~huge_page_mask(h))) - break; - } - } + mincore_hugetlb_page_range(vma, addr, nr, vec); return nr; } -#endif /* * Calculate how many pages there are left in the last level of the @@ -118,53 +183,11 @@ static long do_mincore(unsigned long addr, unsigned long pages, unsigned char *v if (pmd_none_or_clear_bad(pmd)) goto none_mapped; - ptep = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); - for (i = 0; i < nr; i++, ptep++, addr += PAGE_SIZE) { - pte_t pte = *ptep; - - if (pte_none(pte)) { - if (vma->vm_file) { - pgoff = linear_page_index(vma, addr); - vec[i] = mincore_page(vma->vm_file->f_mapping, - pgoff); - } else - vec[i] = 0; - } else if (pte_present(pte)) - vec[i] = 1; - else if (pte_file(pte)) { - pgoff = pte_to_pgoff(pte); - vec[i] = mincore_page(vma->vm_file->f_mapping, pgoff); - } else { /* pte is a swap entry */ - swp_entry_t entry = pte_to_swp_entry(pte); - - if (is_migration_entry(entry)) { - /* migration entries are always uptodate */ - vec[i] = 1; - } else { -#ifdef CONFIG_SWAP - pgoff = entry.val; - vec[i] = mincore_page(&swapper_space, pgoff); -#else - WARN_ON(1); - vec[i] = 1; -#endif - } - } - } - pte_unmap_unlock(ptep - 1, ptl); - + mincore_pte_range(vma, pmd, addr, nr, vec); return nr; none_mapped: - if (vma->vm_file) { - pgoff = linear_page_index(vma, addr); - for (i = 0; i < nr; i++, pgoff++) - vec[i] = mincore_page(vma->vm_file->f_mapping, pgoff); - } else { - for (i = 0; i < nr; i++) - vec[i] = 0; - } - + mincore_unmapped_range(vma, addr, nr, vec); return nr; } |