[PATCH] vmalloc: optimization, cleanup, bugfixes

- reorder 'struct vm_struct' to speedup lookups on CPUS with small cache
  lines.  The fields 'next,addr,size' should be now in the same cache line,
  to speedup lookups.

- One minor cleanup in __get_vm_area_node()

- Bugfixes in vmalloc_user() and vmalloc_32_user() NULL returns from
  __vmalloc() and __find_vm_area() were not tested.

[akpm@osdl.org: remove redundant BUG_ONs]
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/include/linux/vmalloc.h b/include/linux/vmalloc.h
index dc9a29d..924e502 100644
--- a/include/linux/vmalloc.h
+++ b/include/linux/vmalloc.h
@@ -23,13 +23,14 @@
 #endif
 
 struct vm_struct {
+	/* keep next,addr,size together to speedup lookups */
+	struct vm_struct	*next;
 	void			*addr;
 	unsigned long		size;
 	unsigned long		flags;
 	struct page		**pages;
 	unsigned int		nr_pages;
 	unsigned long		phys_addr;
-	struct vm_struct	*next;
 };
 
 /*