slab: make usercopy region 32-bit

If kmem case sizes are 32-bit, then usecopy region should be too.

Link: http://lkml.kernel.org/r/20180305200730.15812-21-adobriyan@gmail.com
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: David Miller <davem@davemloft.net>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/include/linux/slub_def.h b/include/linux/slub_def.h
index bc02fd3..623d6ba 100644
--- a/include/linux/slub_def.h
+++ b/include/linux/slub_def.h
@@ -137,8 +137,8 @@ struct kmem_cache {
 	struct kasan_cache kasan_info;
 #endif
 
-	size_t useroffset;		/* Usercopy region offset */
-	size_t usersize;		/* Usercopy region size */
+	unsigned int useroffset;	/* Usercopy region offset */
+	unsigned int usersize;		/* Usercopy region size */
 
 	struct kmem_cache_node *node[MAX_NUMNODES];
 };