diff options
| -rw-r--r-- | include/linux/mm.h | 18 | ||||
| -rw-r--r-- | mm/hugetlb.c | 2 | ||||
| -rw-r--r-- | mm/page_alloc.c | 2 | ||||
| -rw-r--r-- | mm/swap.c | 4 |
4 files changed, 22 insertions, 4 deletions
diff --git a/include/linux/mm.h b/include/linux/mm.h index 0e266fe1b4c..a17b147c61e 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -296,6 +296,24 @@ void put_pages_list(struct list_head *pages); void split_page(struct page *page, unsigned int order); /* + * Compound pages have a destructor function. Provide a + * prototype for that function and accessor functions. + * These are _only_ valid on the head of a PG_compound page. + */ +typedef void compound_page_dtor(struct page *); + +static inline void set_compound_page_dtor(struct page *page, + compound_page_dtor *dtor) +{ + page[1].lru.next = (void *)dtor; +} + +static inline compound_page_dtor *get_compound_page_dtor(struct page *page) +{ + return (compound_page_dtor *)page[1].lru.next; +} + +/* * Multiple processes may "see" the same page. E.g. for untouched * mappings of /dev/null, all processes see the same page full of * zeroes, and text pages of executables and shared libraries have diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 2911a364481..0ccc7f23025 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -109,7 +109,7 @@ static int alloc_fresh_huge_page(void) if (nid == MAX_NUMNODES) nid = first_node(node_online_map); if (page) { - page[1].lru.next = (void *)free_huge_page; /* dtor */ + set_compound_page_dtor(page, free_huge_page); spin_lock(&hugetlb_lock); nr_huge_pages++; nr_huge_pages_node[page_to_nid(page)]++; diff --git a/mm/page_alloc.c b/mm/page_alloc.c index dc8753bdd47..d539f83c62b 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -230,7 +230,7 @@ static void prep_compound_page(struct page *page, unsigned long order) int i; int nr_pages = 1 << order; - page[1].lru.next = (void *)free_compound_page; /* set dtor */ + set_compound_page_dtor(page, free_compound_page); page[1].lru.prev = (void *)order; for (i = 0; i < nr_pages; i++) { struct page *p = page + i; diff --git a/mm/swap.c b/mm/swap.c index d9a3770d8f3..017e72ca9bb 100644 --- a/mm/swap.c +++ b/mm/swap.c @@ -57,9 +57,9 @@ static void put_compound_page(struct page *page) { page = (struct page *)page_private(page); if (put_page_testzero(page)) { - void (*dtor)(struct page *page); + compound_page_dtor *dtor; - dtor = (void (*)(struct page *))page[1].lru.next; + dtor = get_compound_page_dtor(page); (*dtor)(page); } } |