hugetlb: do not use vma_hugecache_offset() for vma_prio_tree_foreach

0c176d5 ("mm: hugetlb: fix pgoff computation when unmapping page from
vma") fixed pgoff calculation but it has replaced it by
vma_hugecache_offset() which is not approapriate for offsets used for
vma_prio_tree_foreach() because that one expects index in page units
rather than in huge_page_shift.

Using vma_hugecache_offset() is not incorrect because the pgoff will fit
into the same vmas but it is confusing so the standard PAGE_SHIFT based
index calculation is used instead.

Signed-off-by: Michal Hocko <mhocko@suse.cz>
Acked-by: Hillf Danton <dhillf@gmail.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 8536741f069b2449bbaab9e752431fb9eb4527a6..de5d1dcf34fe4f7505295b057393ffbd2768d86f 100644 (file)
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -2480,7 +2480,8 @@ static int unmap_ref_private(struct mm_struct *mm, struct vm_area_struct *vma,
         * from page cache lookup which is in HPAGE_SIZE units.
         */
        address = address & huge_page_mask(h);
-       pgoff = vma_hugecache_offset(h, vma, address);
+       pgoff = ((address - vma->vm_start) >> PAGE_SHIFT) +
+                       vma->vm_pgoff;
        mapping = vma->vm_file->f_dentry->d_inode->i_mapping;
 
        /*