Merge tag 'linux-kselftest-4.8-rc1-fixes' of git://git.kernel.org/pub/scm/linux/kerne...

[cascardo/linux.git] / mm / util.c

diff --git a/mm/util.c b/mm/util.c
index 917e0e3..662cddf 100644 (file)
--- 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();