1 files changed, 19 insertions, 28 deletions

diff --git a/include/linux/mm.h b/include/linux/mm.h
index 864d7221de84..2b97be1147ec 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -72,6 +72,10 @@ extern int mmap_rnd_compat_bits __read_mostly;
 #define __pa_symbol(x)  __pa(RELOC_HIDE((unsigned long)(x), 0))
 #endif
 
+#ifndef page_to_virt
+#define page_to_virt(x)	__va(PFN_PHYS(page_to_pfn(x)))
+#endif
+
 /*
  * To prevent common memory management code establishing
  * a zero page mapping on a read fault.
@@ -443,14 +447,14 @@ unsigned long vmalloc_to_pfn(const void *addr);
  * On nommu, vmalloc/vfree wrap through kmalloc/kfree directly, so there
  * is no special casing required.
  */
-static inline int is_vmalloc_addr(const void *x)
+static inline bool is_vmalloc_addr(const void *x)
 {
 #ifdef CONFIG_MMU
 	unsigned long addr = (unsigned long)x;
 
 	return addr >= VMALLOC_START && addr < VMALLOC_END;
 #else
-	return 0;
+	return false;
 #endif
 }
 #ifdef CONFIG_MMU
@@ -500,11 +504,20 @@ static inline int page_mapcount(struct page *page)
 
 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
 int total_mapcount(struct page *page);
+int page_trans_huge_mapcount(struct page *page, int *total_mapcount);
 #else
 static inline int total_mapcount(struct page *page)
 {
 	return page_mapcount(page);
 }
+static inline int page_trans_huge_mapcount(struct page *page,
+					   int *total_mapcount)
+{
+	int mapcount = page_mapcount(page);
+	if (total_mapcount)
+		*total_mapcount = mapcount;
+	return mapcount;
+}
 #endif
 
 static inline struct page *virt_to_head_page(const void *x)
@@ -721,7 +734,7 @@ static inline void get_page(struct page *page)
 	page = compound_head(page);
 	/*
 	 * Getting a normal page or the head of a compound page
-	 * requires to already have an elevated page->_count.
+	 * requires to already have an elevated page->_refcount.
 	 */
 	VM_BUG_ON_PAGE(page_ref_count(page) <= 0, page);
 	page_ref_inc(page);
@@ -837,10 +850,7 @@ extern int page_cpupid_xchg_last(struct page *page, int cpupid);
 
 static inline void page_cpupid_reset_last(struct page *page)
 {
-	int cpupid = (1 << LAST_CPUPID_SHIFT) - 1;
-
-	page->flags &= ~(LAST_CPUPID_MASK << LAST_CPUPID_PGSHIFT);
-	page->flags |= (cpupid & LAST_CPUPID_MASK) << LAST_CPUPID_PGSHIFT;
+	page->flags |= LAST_CPUPID_MASK << LAST_CPUPID_PGSHIFT;
 }
 #endif /* LAST_CPUPID_NOT_IN_PAGE_FLAGS */
 #else /* !CONFIG_NUMA_BALANCING */
@@ -948,7 +958,7 @@ static inline struct mem_cgroup *page_memcg(struct page *page)
 
 static __always_inline void *lowmem_page_address(const struct page *page)
 {
-	return __va(PFN_PHYS(page_to_pfn(page)));
+	return page_to_virt(page);
 }
 
 #if defined(CONFIG_HIGHMEM) && !defined(WANT_PAGE_VIRTUAL)
@@ -1019,26 +1029,7 @@ static inline pgoff_t page_file_index(struct page *page)
 	return page->index;
 }
 
-/*
- * Return true if this page is mapped into pagetables.
- * For compound page it returns true if any subpage of compound page is mapped.
- */
-static inline bool page_mapped(struct page *page)
-{
-	int i;
-	if (likely(!PageCompound(page)))
-		return atomic_read(&page->_mapcount) >= 0;
-	page = compound_head(page);
-	if (atomic_read(compound_mapcount_ptr(page)) >= 0)
-		return true;
-	if (PageHuge(page))
-		return false;
-	for (i = 0; i < hpage_nr_pages(page); i++) {
-		if (atomic_read(&page[i]._mapcount) >= 0)
-			return true;
-	}
-	return false;
-}
+bool page_mapped(struct page *page);
 
 /*
  * Return true only if the page has been allocated with