From 25ef0e50cca790370ad7838e3ad74db6a6a2d829 Mon Sep 17 00:00:00 2001 From: Johannes Weiner Date: Mon, 24 May 2010 14:32:11 -0700 Subject: mincore: pass ranges as start,end address pairs Instead of passing a start address and a number of pages into the helper functions, convert them to use a start and an end address. Signed-off-by: Johannes Weiner Cc: Andrea Arcangeli Cc: Naoya Horiguchi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/mincore.c | 57 +++++++++++++++++++++++++++------------------------------ 1 file changed, 27 insertions(+), 30 deletions(-) (limited to 'mm/mincore.c') diff --git a/mm/mincore.c b/mm/mincore.c index a0c4c10..211604a 100644 --- a/mm/mincore.c +++ b/mm/mincore.c @@ -20,14 +20,12 @@ #include static void mincore_hugetlb_page_range(struct vm_area_struct *vma, - unsigned long addr, unsigned long nr, + unsigned long addr, unsigned long end, unsigned char *vec) { #ifdef CONFIG_HUGETLB_PAGE struct hstate *h; - int i; - i = 0; h = hstate_vma(vma); while (1) { unsigned char present; @@ -40,10 +38,10 @@ static void mincore_hugetlb_page_range(struct vm_area_struct *vma, addr & huge_page_mask(h)); present = ptep && !huge_pte_none(huge_ptep_get(ptep)); while (1) { - vec[i++] = present; + *vec = present; + vec++; addr += PAGE_SIZE; - /* reach buffer limit */ - if (i == nr) + if (addr == end) return; /* check hugepage border */ if (!(addr & ~huge_page_mask(h))) @@ -86,9 +84,10 @@ static unsigned char mincore_page(struct address_space *mapping, pgoff_t pgoff) } static void mincore_unmapped_range(struct vm_area_struct *vma, - unsigned long addr, unsigned long nr, + unsigned long addr, unsigned long end, unsigned char *vec) { + unsigned long nr = (end - addr) >> PAGE_SHIFT; int i; if (vma->vm_file) { @@ -104,42 +103,44 @@ static void mincore_unmapped_range(struct vm_area_struct *vma, } static void mincore_pte_range(struct vm_area_struct *vma, pmd_t *pmd, - unsigned long addr, unsigned long nr, + unsigned long addr, unsigned long end, unsigned char *vec) { + unsigned long next; 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) { + do { pte_t pte = *ptep; pgoff_t pgoff; + next = addr + PAGE_SIZE; if (pte_none(pte)) - mincore_unmapped_range(vma, addr, 1, vec); + mincore_unmapped_range(vma, addr, next, vec); else if (pte_present(pte)) - vec[i] = 1; + *vec = 1; else if (pte_file(pte)) { pgoff = pte_to_pgoff(pte); - vec[i] = 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 */ - vec[i] = 1; + *vec = 1; } else { #ifdef CONFIG_SWAP pgoff = entry.val; - vec[i] = mincore_page(&swapper_space, pgoff); + *vec = mincore_page(&swapper_space, pgoff); #else WARN_ON(1); - vec[i] = 1; + *vec = 1; #endif } } - } + vec++; + } while (ptep++, addr = next, addr != end); pte_unmap_unlock(ptep - 1, ptl); } @@ -153,25 +154,21 @@ static long do_mincore(unsigned long addr, unsigned long pages, unsigned char *v pgd_t *pgd; pud_t *pud; pmd_t *pmd; - unsigned long nr; struct vm_area_struct *vma; + unsigned long end; vma = find_vma(current->mm, addr); if (!vma || addr < vma->vm_start) return -ENOMEM; - nr = min(pages, (vma->vm_end - addr) >> PAGE_SHIFT); + end = min(vma->vm_end, addr + (pages << PAGE_SHIFT)); if (is_vm_hugetlb_page(vma)) { - mincore_hugetlb_page_range(vma, addr, nr, vec); - return nr; + mincore_hugetlb_page_range(vma, addr, end, vec); + return (end - addr) >> PAGE_SHIFT; } - /* - * Calculate how many pages there are left in the last level of the - * PTE array for our address. - */ - nr = min(nr, PTRS_PER_PTE - ((addr >> PAGE_SHIFT) & (PTRS_PER_PTE-1))); + end = pmd_addr_end(addr, end); pgd = pgd_offset(vma->vm_mm, addr); if (pgd_none_or_clear_bad(pgd)) @@ -183,12 +180,12 @@ static long do_mincore(unsigned long addr, unsigned long pages, unsigned char *v if (pmd_none_or_clear_bad(pmd)) goto none_mapped; - mincore_pte_range(vma, pmd, addr, nr, vec); - return nr; + mincore_pte_range(vma, pmd, addr, end, vec); + return (end - addr) >> PAGE_SHIFT; none_mapped: - mincore_unmapped_range(vma, addr, nr, vec); - return nr; + mincore_unmapped_range(vma, addr, end, vec); + return (end - addr) >> PAGE_SHIFT; } /* -- cgit v1.1