block: fix an address space warning in blk-map.c

Change type of 2nd parameter of blk_rq_aligned() into unsigned long
and remove unnecessary casting. Now we can call it with 'uaddr'
instead of 'ubuf' in __blk_rq_map_user() so that it can remove
following warnings from sparse:

 block/blk-map.c:57:31: warning: incorrect type in argument 2 (different address spaces)
 block/blk-map.c:57:31:    expected void *addr
 block/blk-map.c:57:31:    got void [noderef] <asn:1>*ubuf

However blk_rq_map_kern() needs one more local variable to handle it.

Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 7e66110..780824e 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -1097,11 +1097,11 @@
 	return q ? q->dma_alignment : 511;
 }
 
-static inline int blk_rq_aligned(struct request_queue *q, void *addr,
+static inline int blk_rq_aligned(struct request_queue *q, unsigned long addr,
 				 unsigned int len)
 {
 	unsigned int alignment = queue_dma_alignment(q) | q->dma_pad_mask;
-	return !((unsigned long)addr & alignment) && !(len & alignment);
+	return !(addr & alignment) && !(len & alignment);
 }
 
 /* assumes size > 256 */