From: Huang Ying <[email protected]> To take better advantage of general huge page copying optimization, the target subpage address will be passed to hugetlb_cow(), then copy_user_huge_page(). So we will use both target subpage address and huge page size aligned address in hugetlb_cow(). To distinguish between them, "haddr" is used for huge page size aligned address to be consistent with Transparent Huge Page naming convention.
Now, only huge page size aligned address is used in hugetlb_cow(), so the "address" is renamed to "haddr" in hugetlb_cow() in this patch. Next patch will use target subpage address in hugetlb_cow() too. The patch is just code cleanup without any functionality changes. Signed-off-by: "Huang, Ying" <[email protected]> Suggested-by: Mike Kravetz <[email protected]> Suggested-by: Michal Hocko <[email protected]> Cc: David Rientjes <[email protected]> Cc: Andrea Arcangeli <[email protected]> Cc: "Kirill A. Shutemov" <[email protected]> Cc: Andi Kleen <[email protected]> Cc: Jan Kara <[email protected]> Cc: Matthew Wilcox <[email protected]> Cc: Hugh Dickins <[email protected]> Cc: Minchan Kim <[email protected]> Cc: Shaohua Li <[email protected]> Cc: Christopher Lameter <[email protected]> Cc: "Aneesh Kumar K.V" <[email protected]> Cc: Punit Agrawal <[email protected]> Cc: Anshuman Khandual <[email protected]> --- mm/hugetlb.c | 26 ++++++++++++-------------- 1 file changed, 12 insertions(+), 14 deletions(-) diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 696befffe6f7..ad3bec2ed269 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -3500,7 +3500,7 @@ static void unmap_ref_private(struct mm_struct *mm, struct vm_area_struct *vma, * Keep the pte_same checks anyway to make transition from the mutex easier. */ static int hugetlb_cow(struct mm_struct *mm, struct vm_area_struct *vma, - unsigned long address, pte_t *ptep, + unsigned long haddr, pte_t *ptep, struct page *pagecache_page, spinlock_t *ptl) { pte_t pte; @@ -3518,7 +3518,7 @@ static int hugetlb_cow(struct mm_struct *mm, struct vm_area_struct *vma, * and just make the page writable */ if (page_mapcount(old_page) == 1 && PageAnon(old_page)) { page_move_anon_rmap(old_page, vma); - set_huge_ptep_writable(vma, address, ptep); + set_huge_ptep_writable(vma, haddr, ptep); return 0; } @@ -3542,7 +3542,7 @@ static int hugetlb_cow(struct mm_struct *mm, struct vm_area_struct *vma, * be acquired again before returning to the caller, as expected. */ spin_unlock(ptl); - new_page = alloc_huge_page(vma, address, outside_reserve); + new_page = alloc_huge_page(vma, haddr, outside_reserve); if (IS_ERR(new_page)) { /* @@ -3555,11 +3555,10 @@ static int hugetlb_cow(struct mm_struct *mm, struct vm_area_struct *vma, if (outside_reserve) { put_page(old_page); BUG_ON(huge_pte_none(pte)); - unmap_ref_private(mm, vma, old_page, address); + unmap_ref_private(mm, vma, old_page, haddr); BUG_ON(huge_pte_none(pte)); spin_lock(ptl); - ptep = huge_pte_offset(mm, address & huge_page_mask(h), - huge_page_size(h)); + ptep = huge_pte_offset(mm, haddr, huge_page_size(h)); if (likely(ptep && pte_same(huge_ptep_get(ptep), pte))) goto retry_avoidcopy; @@ -3584,12 +3583,12 @@ static int hugetlb_cow(struct mm_struct *mm, struct vm_area_struct *vma, goto out_release_all; } - copy_user_huge_page(new_page, old_page, address, vma, + copy_user_huge_page(new_page, old_page, haddr, vma, pages_per_huge_page(h)); __SetPageUptodate(new_page); set_page_huge_active(new_page); - mmun_start = address & huge_page_mask(h); + mmun_start = haddr; mmun_end = mmun_start + huge_page_size(h); mmu_notifier_invalidate_range_start(mm, mmun_start, mmun_end); @@ -3598,25 +3597,24 @@ static int hugetlb_cow(struct mm_struct *mm, struct vm_area_struct *vma, * before the page tables are altered */ spin_lock(ptl); - ptep = huge_pte_offset(mm, address & huge_page_mask(h), - huge_page_size(h)); + ptep = huge_pte_offset(mm, haddr, huge_page_size(h)); if (likely(ptep && pte_same(huge_ptep_get(ptep), pte))) { ClearPagePrivate(new_page); /* Break COW */ - huge_ptep_clear_flush(vma, address, ptep); + huge_ptep_clear_flush(vma, haddr, ptep); mmu_notifier_invalidate_range(mm, mmun_start, mmun_end); - set_huge_pte_at(mm, address, ptep, + set_huge_pte_at(mm, haddr, ptep, make_huge_pte(vma, new_page, 1)); page_remove_rmap(old_page, true); - hugepage_add_new_anon_rmap(new_page, vma, address); + hugepage_add_new_anon_rmap(new_page, vma, haddr); /* Make the old page be freed below */ new_page = old_page; } spin_unlock(ptl); mmu_notifier_invalidate_range_end(mm, mmun_start, mmun_end); out_release_all: - restore_reserve_on_error(h, vma, address, new_page); + restore_reserve_on_error(h, vma, haddr, new_page); put_page(new_page); out_release_old: put_page(old_page); -- 2.16.1
