X-Git-Url: https://git.openpandora.org/cgi-bin/gitweb.cgi?p=pandora-kernel.git;a=blobdiff_plain;f=mm%2Fmincore.c;h=9ac42dc6d7b61481b1eedb8e12b463bd151b1f92;hp=f77433c20279d95c2a87ce7117888e63580c8922;hb=refs%2Fheads%2Fpandora-35;hpb=06ee772043c7ad125f2c2e6a08dc563706f39e8d diff --git a/mm/mincore.c b/mm/mincore.c index f77433c20279..9ac42dc6d7b6 100644 --- a/mm/mincore.c +++ b/mm/mincore.c @@ -19,6 +19,40 @@ #include #include +static void mincore_hugetlb_page_range(struct vm_area_struct *vma, + unsigned long addr, unsigned long end, + unsigned char *vec) +{ +#ifdef CONFIG_HUGETLB_PAGE + struct hstate *h; + + 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 = present; + vec++; + addr += PAGE_SIZE; + if (addr == end) + 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, @@ -49,145 +83,150 @@ static unsigned char mincore_page(struct address_space *mapping, pgoff_t pgoff) return present; } -/* - * Do a chunk of "sys_mincore()". We've already checked - * all the arguments, we hold the mmap semaphore: we should - * just return the amount of info we're asked for. - */ -static long do_mincore(unsigned long addr, unsigned char *vec, unsigned long pages) +static void mincore_unmapped_range(struct vm_area_struct *vma, + unsigned long addr, unsigned long end, + unsigned char *vec) { - pgd_t *pgd; - pud_t *pud; - pmd_t *pmd; - pte_t *ptep; - spinlock_t *ptl; - unsigned long nr; + unsigned long nr = (end - addr) >> PAGE_SHIFT; int i; - pgoff_t pgoff; - struct vm_area_struct *vma = find_vma(current->mm, addr); - /* - * find_vma() didn't find anything above us, or we're - * in an unmapped hole in the address space: ENOMEM. - */ - if (!vma || addr < vma->vm_start) - return -ENOMEM; - -#ifdef CONFIG_HUGETLB_PAGE - if (is_vm_hugetlb_page(vma)) { - struct hstate *h; - unsigned long nr_huge; - unsigned char present; + if (vma->vm_file) { + pgoff_t pgoff; - i = 0; - nr = min(pages, (vma->vm_end - addr) >> PAGE_SHIFT); - h = hstate_vma(vma); - nr_huge = ((addr + pages * PAGE_SIZE - 1) >> huge_page_shift(h)) - - (addr >> huge_page_shift(h)) + 1; - nr_huge = min(nr_huge, - (vma->vm_end - addr) >> huge_page_shift(h)); - while (1) { - /* hugepage always in RAM for now, - * but generally it needs to be check */ - 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)) - >> PAGE_SHIFT)) - break; - } - } - return nr; + 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; } -#endif - - /* - * Calculate how many pages there are left in the last level of the - * PTE array for our address. - */ - nr = PTRS_PER_PTE - ((addr >> PAGE_SHIFT) & (PTRS_PER_PTE-1)); - - /* - * Don't overrun this vma - */ - nr = min(nr, (vma->vm_end - addr) >> PAGE_SHIFT); - - /* - * Don't return more than the caller asked for - */ - nr = min(nr, pages); +} - pgd = pgd_offset(vma->vm_mm, addr); - if (pgd_none_or_clear_bad(pgd)) - goto none_mapped; - pud = pud_offset(pgd, addr); - if (pud_none_or_clear_bad(pud)) - goto none_mapped; - pmd = pmd_offset(pud, addr); - if (pmd_none_or_clear_bad(pmd)) - goto none_mapped; +static void mincore_pte_range(struct vm_area_struct *vma, pmd_t *pmd, + unsigned long addr, unsigned long end, + unsigned char *vec) +{ + unsigned long next; + spinlock_t *ptl; + pte_t *ptep; ptep = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); - for (i = 0; i < nr; i++, ptep++, addr += PAGE_SIZE) { - unsigned char present; + do { pte_t pte = *ptep; + pgoff_t pgoff; - if (pte_present(pte)) { - present = 1; - - } else if (pte_none(pte)) { - if (vma->vm_file) { - pgoff = linear_page_index(vma, addr); - present = mincore_page(vma->vm_file->f_mapping, - pgoff); - } else - present = 0; - - } else if (pte_file(pte)) { + next = addr + PAGE_SIZE; + if (pte_none(pte)) + mincore_unmapped_range(vma, addr, next, vec); + else if (pte_present(pte)) + *vec = 1; + else if (pte_file(pte)) { pgoff = pte_to_pgoff(pte); - present = mincore_page(vma->vm_file->f_mapping, pgoff); - + *vec = 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 */ - present = 1; + *vec = 1; } else { #ifdef CONFIG_SWAP pgoff = entry.val; - present = mincore_page(&swapper_space, pgoff); + *vec = mincore_page(&swapper_space, pgoff); #else WARN_ON(1); - present = 1; + *vec = 1; #endif } } + vec++; + } while (ptep++, addr = next, addr != end); + pte_unmap_unlock(ptep - 1, ptl); +} - vec[i] = present; - } - pte_unmap_unlock(ptep-1, ptl); +static void mincore_pmd_range(struct vm_area_struct *vma, pud_t *pud, + unsigned long addr, unsigned long end, + unsigned char *vec) +{ + unsigned long next; + pmd_t *pmd; - return nr; + pmd = pmd_offset(pud, addr); + do { + next = pmd_addr_end(addr, end); + if (pmd_none_or_clear_bad(pmd)) + mincore_unmapped_range(vma, addr, next, vec); + else + mincore_pte_range(vma, pmd, addr, next, vec); + vec += (next - addr) >> PAGE_SHIFT; + } while (pmd++, addr = next, addr != end); +} -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; +static void mincore_pud_range(struct vm_area_struct *vma, pgd_t *pgd, + unsigned long addr, unsigned long end, + unsigned char *vec) +{ + unsigned long next; + pud_t *pud; + + pud = pud_offset(pgd, addr); + do { + next = pud_addr_end(addr, end); + if (pud_none_or_clear_bad(pud)) + mincore_unmapped_range(vma, addr, next, vec); + else + mincore_pmd_range(vma, pud, addr, next, vec); + vec += (next - addr) >> PAGE_SHIFT; + } while (pud++, addr = next, addr != end); +} + +static void mincore_page_range(struct vm_area_struct *vma, + unsigned long addr, unsigned long end, + unsigned char *vec) +{ + unsigned long next; + pgd_t *pgd; + + pgd = pgd_offset(vma->vm_mm, addr); + do { + next = pgd_addr_end(addr, end); + if (pgd_none_or_clear_bad(pgd)) + mincore_unmapped_range(vma, addr, next, vec); + else + mincore_pud_range(vma, pgd, addr, next, vec); + vec += (next - addr) >> PAGE_SHIFT; + } while (pgd++, addr = next, addr != end); +} + +/* + * Do a chunk of "sys_mincore()". We've already checked + * all the arguments, we hold the mmap semaphore: we should + * just return the amount of info we're asked for. + */ +static long do_mincore(unsigned long addr, unsigned long pages, unsigned char *vec) +{ + struct vm_area_struct *vma; + unsigned long end; + + vma = find_vma(current->mm, addr); + if (!vma || addr < vma->vm_start) + return -ENOMEM; + + end = min(vma->vm_end, addr + (pages << PAGE_SHIFT)); + + if (is_vm_hugetlb_page(vma)) { + mincore_hugetlb_page_range(vma, addr, end, vec); + return (end - addr) >> PAGE_SHIFT; } - return nr; + end = pmd_addr_end(addr, end); + + if (is_vm_hugetlb_page(vma)) + mincore_hugetlb_page_range(vma, addr, end, vec); + else + mincore_page_range(vma, addr, end, vec); + + return (end - addr) >> PAGE_SHIFT; } /* @@ -247,7 +286,7 @@ SYSCALL_DEFINE3(mincore, unsigned long, start, size_t, len, * the temporary buffer size. */ down_read(¤t->mm->mmap_sem); - retval = do_mincore(start, tmp, min(pages, PAGE_SIZE)); + retval = do_mincore(start, min(pages, PAGE_SIZE), tmp); up_read(¤t->mm->mmap_sem); if (retval <= 0)