1 files changed, 78 insertions, 12 deletions

diff --git a/include/linux/mm.h b/include/linux/mm.h
index 5411de93a363..d557d15fc195 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -48,7 +48,32 @@ static inline void set_max_mapnr(unsigned long limit)
 static inline void set_max_mapnr(unsigned long limit) { }
 #endif
 
-extern unsigned long totalram_pages;
+extern atomic_long_t _totalram_pages;
+static inline unsigned long totalram_pages(void)
+{
+	return (unsigned long)atomic_long_read(&_totalram_pages);
+}
+
+static inline void totalram_pages_inc(void)
+{
+	atomic_long_inc(&_totalram_pages);
+}
+
+static inline void totalram_pages_dec(void)
+{
+	atomic_long_dec(&_totalram_pages);
+}
+
+static inline void totalram_pages_add(long count)
+{
+	atomic_long_add(count, &_totalram_pages);
+}
+
+static inline void totalram_pages_set(long val)
+{
+	atomic_long_set(&_totalram_pages, val);
+}
+
 extern void * high_memory;
 extern int page_cluster;
 
@@ -98,10 +123,45 @@ extern int mmap_rnd_compat_bits __read_mostly;
 
 /*
  * On some architectures it is expensive to call memset() for small sizes.
- * Those architectures should provide their own implementation of "struct page"
- * zeroing by defining this macro in <asm/pgtable.h>.
+ * If an architecture decides to implement their own version of
+ * mm_zero_struct_page they should wrap the defines below in a #ifndef and
+ * define their own version of this macro in <asm/pgtable.h>
+ */
+#if BITS_PER_LONG == 64
+/* This function must be updated when the size of struct page grows above 80
+ * or reduces below 56. The idea that compiler optimizes out switch()
+ * statement, and only leaves move/store instructions. Also the compiler can
+ * combine write statments if they are both assignments and can be reordered,
+ * this can result in several of the writes here being dropped.
  */
-#ifndef mm_zero_struct_page
+#define	mm_zero_struct_page(pp) __mm_zero_struct_page(pp)
+static inline void __mm_zero_struct_page(struct page *page)
+{
+	unsigned long *_pp = (void *)page;
+
+	 /* Check that struct page is either 56, 64, 72, or 80 bytes */
+	BUILD_BUG_ON(sizeof(struct page) & 7);
+	BUILD_BUG_ON(sizeof(struct page) < 56);
+	BUILD_BUG_ON(sizeof(struct page) > 80);
+
+	switch (sizeof(struct page)) {
+	case 80:
+		_pp[9] = 0;	/* fallthrough */
+	case 72:
+		_pp[8] = 0;	/* fallthrough */
+	case 64:
+		_pp[7] = 0;	/* fallthrough */
+	case 56:
+		_pp[6] = 0;
+		_pp[5] = 0;
+		_pp[4] = 0;
+		_pp[3] = 0;
+		_pp[2] = 0;
+		_pp[1] = 0;
+		_pp[0] = 0;
+	}
+}
+#else
 #define mm_zero_struct_page(pp)  ((void)memset((pp), 0, sizeof(struct page)))
 #endif
 
@@ -1136,11 +1196,18 @@ static inline void set_page_node(struct page *page, unsigned long node)
 	page->flags |= (node & NODES_MASK) << NODES_PGSHIFT;
 }
 
+static inline void set_page_reserved(struct page *page, bool reserved)
+{
+	page->flags &= ~(1ul << PG_reserved);
+	page->flags |= (unsigned long)(!!reserved) << PG_reserved;
+}
+
 static inline void set_page_links(struct page *page, enum zone_type zone,
-	unsigned long node, unsigned long pfn)
+	unsigned long node, unsigned long pfn, bool reserved)
 {
 	set_page_zone(page, zone);
 	set_page_node(page, node);
+	set_page_reserved(page, reserved);
 #ifdef SECTION_IN_PAGE_FLAGS
 	set_page_section(page, pfn_to_section_nr(pfn));
 #endif
@@ -1817,8 +1884,8 @@ static inline void mm_inc_nr_ptes(struct mm_struct *mm) {}
 static inline void mm_dec_nr_ptes(struct mm_struct *mm) {}
 #endif
 
-int __pte_alloc(struct mm_struct *mm, pmd_t *pmd, unsigned long address);
-int __pte_alloc_kernel(pmd_t *pmd, unsigned long address);
+int __pte_alloc(struct mm_struct *mm, pmd_t *pmd);
+int __pte_alloc_kernel(pmd_t *pmd);
 
 /*
  * The following ifdef needed to get the 4level-fixup.h header to work.
@@ -1956,18 +2023,17 @@ static inline void pgtable_page_dtor(struct page *page)
 	pte_unmap(pte);					\
 } while (0)
 
-#define pte_alloc(mm, pmd, address)			\
-	(unlikely(pmd_none(*(pmd))) && __pte_alloc(mm, pmd, address))
+#define pte_alloc(mm, pmd) (unlikely(pmd_none(*(pmd))) && __pte_alloc(mm, pmd))
 
 #define pte_alloc_map(mm, pmd, address)			\
-	(pte_alloc(mm, pmd, address) ? NULL : pte_offset_map(pmd, address))
+	(pte_alloc(mm, pmd) ? NULL : pte_offset_map(pmd, address))
 
 #define pte_alloc_map_lock(mm, pmd, address, ptlp)	\
-	(pte_alloc(mm, pmd, address) ?			\
+	(pte_alloc(mm, pmd) ?			\
 		 NULL : pte_offset_map_lock(mm, pmd, address, ptlp))
 
 #define pte_alloc_kernel(pmd, address)			\
-	((unlikely(pmd_none(*(pmd))) && __pte_alloc_kernel(pmd, address))? \
+	((unlikely(pmd_none(*(pmd))) && __pte_alloc_kernel(pmd))? \
 		NULL: pte_offset_kernel(pmd, address))
 
 #if USE_SPLIT_PMD_PTLOCKS