diff options
Diffstat (limited to 'mm')
| -rw-r--r-- | mm/hugetlb.c | 17 |
1 files changed, 17 insertions, 0 deletions
diff --git a/mm/hugetlb.c b/mm/hugetlb.c index e2bfbf73a551..5cf99bf8cce2 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -690,6 +690,23 @@ int PageHuge(struct page *page) } EXPORT_SYMBOL_GPL(PageHuge); +pgoff_t __basepage_index(struct page *page) +{ + struct page *page_head = compound_head(page); + pgoff_t index = page_index(page_head); + unsigned long compound_idx; + + if (!PageHuge(page_head)) + return page_index(page); + + if (compound_order(page_head) >= MAX_ORDER) + compound_idx = page_to_pfn(page) - page_to_pfn(page_head); + else + compound_idx = page - page_head; + + return (index << compound_order(page_head)) + compound_idx; +} + static struct page *alloc_fresh_huge_page_node(struct hstate *h, int nid) { struct page *page; |