diff options
| -rw-r--r-- | include/linux/mm.h | 5 | ||||
| -rw-r--r-- | include/linux/mm_types.h | 1 | ||||
| -rw-r--r-- | mm/page_alloc.c | 5 |
3 files changed, 8 insertions, 3 deletions
diff --git a/include/linux/mm.h b/include/linux/mm.h index e7602a3bcef1..10b1e6e5f885 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -922,12 +922,15 @@ static inline int compound_pincount(struct page *page) static inline void set_compound_order(struct page *page, unsigned int order) { page[1].compound_order = order; + page[1].compound_nr = 1U << order; } /* Returns the number of pages in this potentially compound page. */ static inline unsigned long compound_nr(struct page *page) { - return 1UL << compound_order(page); + if (!PageHead(page)) + return 1; + return page[1].compound_nr; } /* Returns the number of bytes in this potentially compound page. */ diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h index 0277fbab7c93..496c3ff97cce 100644 --- a/include/linux/mm_types.h +++ b/include/linux/mm_types.h @@ -134,6 +134,7 @@ struct page { unsigned char compound_dtor; unsigned char compound_order; atomic_t compound_mapcount; + unsigned int compound_nr; /* 1 << compound_order */ }; struct { /* Second tail page of compound page */ unsigned long _compound_pad_1; /* compound_head */ diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 8b7d0ecf30b1..0e2bab486fea 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -666,8 +666,6 @@ void prep_compound_page(struct page *page, unsigned int order) int i; int nr_pages = 1 << order; - set_compound_page_dtor(page, COMPOUND_PAGE_DTOR); - set_compound_order(page, order); __SetPageHead(page); for (i = 1; i < nr_pages; i++) { struct page *p = page + i; @@ -675,6 +673,9 @@ void prep_compound_page(struct page *page, unsigned int order) p->mapping = TAIL_MAPPING; set_compound_head(p, page); } + + set_compound_page_dtor(page, COMPOUND_PAGE_DTOR); + set_compound_order(page, order); atomic_set(compound_mapcount_ptr(page), -1); if (hpage_pincount_available(page)) atomic_set(compound_pincount_ptr(page), 0); |