Linux-libre 4.8.2-gnupck-4.8.2-gnu

1 files changed, 12 insertions, 4 deletions

diff --git a/mm/util.c b/mm/util.c
index 917e0e3d0..662cddf91 100644
--- a/mm/util.c
+++ b/mm/util.c
@@ -399,10 +399,12 @@ struct address_space *page_mapping(struct page *page)
 	}
 
 	mapping = page->mapping;
-	if ((unsigned long)mapping & PAGE_MAPPING_FLAGS)
+	if ((unsigned long)mapping & PAGE_MAPPING_ANON)
 		return NULL;
-	return mapping;
+
+	return (void *)((unsigned long)mapping & ~PAGE_MAPPING_FLAGS);
 }
+EXPORT_SYMBOL(page_mapping);
 
 /* Slow path of page_mapcount() for compound pages */
 int __page_mapcount(struct page *page)
@@ -410,6 +412,12 @@ int __page_mapcount(struct page *page)
 	int ret;
 
 	ret = atomic_read(&page->_mapcount) + 1;
+	/*
+	 * For file THP page->_mapcount contains total number of mapping
+	 * of the page: no need to look into compound_mapcount.
+	 */
+	if (!PageAnon(page) && !PageHuge(page))
+		return ret;
 	page = compound_head(page);
 	ret += atomic_read(compound_mapcount_ptr(page)) + 1;
 	if (PageDoubleMap(page))
@@ -520,7 +528,7 @@ int __vm_enough_memory(struct mm_struct *mm, long pages, int cap_sys_admin)
 
 	if (sysctl_overcommit_memory == OVERCOMMIT_GUESS) {
 		free = global_page_state(NR_FREE_PAGES);
-		free += global_page_state(NR_FILE_PAGES);
+		free += global_node_page_state(NR_FILE_PAGES);
 
 		/*
 		 * shmem pages shouldn't be counted as free in this
@@ -528,7 +536,7 @@ int __vm_enough_memory(struct mm_struct *mm, long pages, int cap_sys_admin)
 		 * that won't affect the overall amount of available
 		 * memory in the system.
 		 */
-		free -= global_page_state(NR_SHMEM);
+		free -= global_node_page_state(NR_SHMEM);
 
 		free += get_nr_swap_pages();