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>

2 files changed, 5 insertions, 4 deletions

diff --git a/block/blk-map.c b/block/blk-map.c
index c65d7593f7f1..ac0f7d46db63 100644
--- a/block/blk-map.c
+++ b/block/blk-map.c
@@ -54,7 +54,7 @@ static int __blk_rq_map_user(struct request_queue *q, struct request *rq,
          * direct dma. else, set up kernel bounce buffers
          */
         uaddr = (unsigned long) ubuf;
-        if (blk_rq_aligned(q, ubuf, len) && !map_data)
+        if (blk_rq_aligned(q, uaddr, len) && !map_data)
                 bio = bio_map_user(q, NULL, uaddr, len, reading, gfp_mask);
         else
                 bio = bio_copy_user(q, map_data, uaddr, len, reading, gfp_mask);
@@ -288,6 +288,7 @@ int blk_rq_map_kern(struct request_queue *q, struct request *rq, void *kbuf,
                     unsigned int len, gfp_t gfp_mask)
 {
         int reading = rq_data_dir(rq) == READ;
+        unsigned long addr = (unsigned long) kbuf;
         int do_copy = 0;
         struct bio *bio;
         int ret;
@@ -297,7 +298,7 @@ int blk_rq_map_kern(struct request_queue *q, struct request *rq, void *kbuf,
         if (!len || !kbuf)
                 return -EINVAL;
 
-        do_copy = !blk_rq_aligned(q, kbuf, len) || object_is_on_stack(kbuf);
+        do_copy = !blk_rq_aligned(q, addr, len) || object_is_on_stack(kbuf);
         if (do_copy)
                 bio = bio_copy_kern(q, kbuf, len, gfp_mask, reading);
         else
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 7e661106270a..780824edac16 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -1097,11 +1097,11 @@ static inline int queue_dma_alignment(struct request_queue *q)
         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 */