Commit 14417799 authored by Namhyung Kim's avatar Namhyung Kim Committed by Jens Axboe
Browse files

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: default avatarNamhyung Kim <namhyung@gmail.com>
Signed-off-by: default avatarJens Axboe <jaxboe@fusionio.com>
parent 8dcbdc74

block/blk-map.c

+3 −2
Original line number Diff line number Diff line
@@ -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

include/linux/blkdev.h

+2 −2
Original line number Diff line number Diff line
@@ -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 */

CRA Git | Maintained and supported by SUSTech CRA and CCSE