mm: uninline and cleanup page-mapping related helpers

Most-used page->mapping helper -- page_mapping() -- has already uninlined.
 Let's uninline also page_rmapping() and page_anon_vma().  It saves us
depending on configuration around 400 bytes in text:

   text	   data	    bss	    dec	    hex	filename
 660318	  99254	 410000	1169572	 11d8a4	mm/built-in.o-before
 659854	  99254	 410000	1169108	 11d6d4	mm/built-in.o

I also tried to make code a bit more clean.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 68c21b2..0e7bb21 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -950,14 +950,10 @@
 #define page_address_init()  do { } while(0)
 #endif
 
+extern void *page_rmapping(struct page *page);
+extern struct anon_vma *page_anon_vma(struct page *page);
 extern struct address_space *page_mapping(struct page *page);
 
-/* Neutral page->mapping pointer to address_space or anon_vma or other */
-static inline void *page_rmapping(struct page *page)
-{
-	return (void *)((unsigned long)page->mapping & ~PAGE_MAPPING_FLAGS);
-}
-
 extern struct address_space *__page_file_mapping(struct page *);
 
 static inline
diff --git a/include/linux/rmap.h b/include/linux/rmap.h
index c4c559a..c89c53a 100644
--- a/include/linux/rmap.h
+++ b/include/linux/rmap.h
@@ -105,14 +105,6 @@
 		__put_anon_vma(anon_vma);
 }
 
-static inline struct anon_vma *page_anon_vma(struct page *page)
-{
-	if (((unsigned long)page->mapping & PAGE_MAPPING_FLAGS) !=
-					    PAGE_MAPPING_ANON)
-		return NULL;
-	return page_rmapping(page);
-}
-
 static inline void vma_lock_anon_vma(struct vm_area_struct *vma)
 {
 	struct anon_vma *anon_vma = vma->anon_vma;