[PATCH 17/17] blk-map/bio: remove superflous @q from blk_rq_map_{user|kern}*()

[Tejun Heo <tj@kernel.org>]

Impact: API cleanup

All initialized requests must and are guaranteed to have rq->q set.
Taking both @q and @rq parameters doesn't improve anything.  It only
adds pathological corner case where @q != !@rq->q.  Kill the
superflous @q parameter from blk_rq_map_{user|kern}*().

Signed-off-by: Tejun Heo <tj@kernel.org>
---
 block/blk-map.c                            |   27 +++++++++++----------------
 block/bsg.c                                |    5 ++---
 block/scsi_ioctl.c                         |    6 +++---
 drivers/block/pktcdvd.c                    |    2 +-
 drivers/cdrom/cdrom.c                      |    2 +-
 drivers/scsi/device_handler/scsi_dh_alua.c |    2 +-
 drivers/scsi/device_handler/scsi_dh_emc.c  |    2 +-
 drivers/scsi/device_handler/scsi_dh_rdac.c |    2 +-
 drivers/scsi/scsi_lib.c                    |    7 +++----
 drivers/scsi/scsi_tgt_lib.c                |    3 +--
 drivers/scsi/sg.c                          |    6 +++---
 drivers/scsi/st.c                          |    3 +--
 include/linux/blkdev.h                     |   15 +++++++--------
 13 files changed, 36 insertions(+), 46 deletions(-)

diff --git a/block/blk-map.c b/block/blk-map.c
index f60f439..885d359 100644
--- a/block/blk-map.c
+++ b/block/blk-map.c
@@ -10,7 +10,6 @@
 
 /**
  * blk_rq_map_user_iov - map user data to a request, for REQ_TYPE_BLOCK_PC usage
- * @q:		request queue where request should be inserted
  * @rq:		request to map data to
  * @md:		pointer to the rq_map_data holding pages (if necessary)
  * @iov:	pointer to the iovec
@@ -30,10 +29,10 @@
  *    original bio must be passed back in to blk_rq_unmap_user() for proper
  *    unmapping.
  */
-int blk_rq_map_user_iov(struct request_queue *q, struct request *rq,
-			struct rq_map_data *md, struct iovec *iov, int count,
-			gfp_t gfp)
+int blk_rq_map_user_iov(struct request *rq, struct rq_map_data *md,
+			struct iovec *iov, int count, gfp_t gfp)
 {
+	struct request_queue *q = rq->q;
 	struct bio *bio = ERR_PTR(-EINVAL);
 	int rw = rq_data_dir(rq);
 
@@ -66,7 +65,6 @@ EXPORT_SYMBOL(blk_rq_map_user_iov);
 
 /**
  * blk_rq_map_user - map user data to a request, for REQ_TYPE_BLOCK_PC usage
- * @q:		request queue where request should be inserted
  * @rq:		request structure to fill
  * @md:		pointer to the rq_map_data holding pages (if necessary)
  * @ubuf:	the user buffer
@@ -86,16 +84,15 @@ EXPORT_SYMBOL(blk_rq_map_user_iov);
  *    original bio must be passed back in to blk_rq_unmap_user() for proper
  *    unmapping.
  */
-int blk_rq_map_user(struct request_queue *q, struct request *rq,
-		    struct rq_map_data *md, void __user *ubuf,
-		    unsigned long len, gfp_t gfp)
+int blk_rq_map_user(struct request *rq, struct rq_map_data *md,
+		    void __user *ubuf, unsigned long len, gfp_t gfp)
 {
 	struct iovec iov;
 
 	iov.iov_base = ubuf;
 	iov.iov_len = len;
 
-	return blk_rq_map_user_iov(q, rq, md, &iov, 1, gfp);
+	return blk_rq_map_user_iov(rq, md, &iov, 1, gfp);
 }
 EXPORT_SYMBOL(blk_rq_map_user);
 
@@ -128,7 +125,6 @@ EXPORT_SYMBOL(blk_rq_unmap_user);
 
 /**
  * blk_rq_map_kern_sg - map kernel data to a request, for REQ_TYPE_BLOCK_PC
- * @q:		request queue where request should be inserted
  * @rq:		request to fill
  * @sgl:	area to map
  * @nents:	number of elements in @sgl
@@ -138,9 +134,10 @@ EXPORT_SYMBOL(blk_rq_unmap_user);
  *    Data will be mapped directly if possible. Otherwise a bounce
  *    buffer is used.
  */
-int blk_rq_map_kern_sg(struct request_queue *q, struct request *rq,
-		       struct scatterlist *sgl, int nents, gfp_t gfp)
+int blk_rq_map_kern_sg(struct request *rq, struct scatterlist *sgl, int nents,
+		       gfp_t gfp)
 {
+	struct request_queue *q = rq->q;
 	int rw = rq_data_dir(rq);
 	struct bio *bio;
 
@@ -165,7 +162,6 @@ EXPORT_SYMBOL(blk_rq_map_kern_sg);
 
 /**
  * blk_rq_map_kern - map kernel data to a request, for REQ_TYPE_BLOCK_PC usage
- * @q:		request queue where request should be inserted
  * @rq:		request to fill
  * @kbuf:	the kernel buffer
  * @len:	length of user data
@@ -175,13 +171,12 @@ EXPORT_SYMBOL(blk_rq_map_kern_sg);
  *    Data will be mapped directly if possible. Otherwise a bounce
  *    buffer is used.
  */
-int blk_rq_map_kern(struct request_queue *q, struct request *rq, void *kbuf,
-		    unsigned int len, gfp_t gfp)
+int blk_rq_map_kern(struct request *rq, void *kbuf, unsigned int len, gfp_t gfp)
 {
 	struct scatterlist sg;
 
 	sg_init_one(&sg, kbuf, len);
 
-	return blk_rq_map_kern_sg(q, rq, &sg, 1, gfp);
+	return blk_rq_map_kern_sg(rq, &sg, 1, gfp);
 }
 EXPORT_SYMBOL(blk_rq_map_kern);
diff --git a/block/bsg.c b/block/bsg.c
index 206060e..69c222a 100644
--- a/block/bsg.c
+++ b/block/bsg.c
@@ -283,7 +283,7 @@ bsg_map_hdr(struct bsg_device *bd, struct sg_io_v4 *hdr, fmode_t has_write_perm,
 		next_rq->cmd_type = rq->cmd_type;
 
 		dxferp = (void*)(unsigned long)hdr->din_xferp;
-		ret =  blk_rq_map_user(q, next_rq, NULL, dxferp,
+		ret =  blk_rq_map_user(next_rq, NULL, dxferp,
 				       hdr->din_xfer_len, GFP_KERNEL);
 		if (ret)
 			goto out;
@@ -299,8 +299,7 @@ bsg_map_hdr(struct bsg_device *bd, struct sg_io_v4 *hdr, fmode_t has_write_perm,
 		dxfer_len = 0;
 
 	if (dxfer_len) {
-		ret = blk_rq_map_user(q, rq, NULL, dxferp, dxfer_len,
-				      GFP_KERNEL);
+		ret = blk_rq_map_user(rq, NULL, dxferp, dxfer_len, GFP_KERNEL);
 		if (ret)
 			goto out;
 	}
diff --git a/block/scsi_ioctl.c b/block/scsi_ioctl.c
index fd538f8..a98e4ec 100644
--- a/block/scsi_ioctl.c
+++ b/block/scsi_ioctl.c
@@ -306,11 +306,11 @@ static int sg_io(struct request_queue *q, struct gendisk *bd_disk,
 		hdr->iovec_count = iov_shorten(iov, hdr->iovec_count,
 					       hdr->dxfer_len);
 
-		ret = blk_rq_map_user_iov(q, rq, NULL, iov, hdr->iovec_count,
+		ret = blk_rq_map_user_iov(rq, NULL, iov, hdr->iovec_count,
 					  GFP_KERNEL);
 		kfree(iov);
 	} else if (hdr->dxfer_len)
-		ret = blk_rq_map_user(q, rq, NULL, hdr->dxferp, hdr->dxfer_len,
+		ret = blk_rq_map_user(rq, NULL, hdr->dxferp, hdr->dxfer_len,
 				      GFP_KERNEL);
 
 	if (ret)
@@ -449,7 +449,7 @@ int sg_scsi_ioctl(struct request_queue *q, struct gendisk *disk, fmode_t mode,
 		break;
 	}
 
-	if (bytes && blk_rq_map_kern(q, rq, buffer, bytes, __GFP_WAIT)) {
+	if (bytes && blk_rq_map_kern(rq, buffer, bytes, __GFP_WAIT)) {
 		err = DRIVER_ERROR << 24;
 		goto out;
 	}
diff --git a/drivers/block/pktcdvd.c b/drivers/block/pktcdvd.c
index dc7a8c3..a4e5e9b 100644
--- a/drivers/block/pktcdvd.c
+++ b/drivers/block/pktcdvd.c
@@ -771,7 +771,7 @@ static int pkt_generic_packet(struct pktcdvd_device *pd, struct packet_command *
 			     WRITE : READ, __GFP_WAIT);
 
 	if (cgc->buflen) {
-		if (blk_rq_map_kern(q, rq, cgc->buffer, cgc->buflen, __GFP_WAIT))
+		if (blk_rq_map_kern(rq, cgc->buffer, cgc->buflen, __GFP_WAIT))
 			goto out;
 	}
 
diff --git a/drivers/cdrom/cdrom.c b/drivers/cdrom/cdrom.c
index cceace6..ef67aec 100644
--- a/drivers/cdrom/cdrom.c
+++ b/drivers/cdrom/cdrom.c
@@ -2112,7 +2112,7 @@ static int cdrom_read_cdda_bpc(struct cdrom_device_info *cdi, __u8 __user *ubuf,
 			break;
 		}
 
-		ret = blk_rq_map_user(q, rq, NULL, ubuf, len, GFP_KERNEL);
+		ret = blk_rq_map_user(rq, NULL, ubuf, len, GFP_KERNEL);
 		if (ret) {
 			blk_put_request(rq);
 			break;
diff --git a/drivers/scsi/device_handler/scsi_dh_alua.c b/drivers/scsi/device_handler/scsi_dh_alua.c
index e356b43..f3cb900 100644
--- a/drivers/scsi/device_handler/scsi_dh_alua.c
+++ b/drivers/scsi/device_handler/scsi_dh_alua.c
@@ -101,7 +101,7 @@ static struct request *get_alua_req(struct scsi_device *sdev,
 		return NULL;
 	}
 
-	if (buflen && blk_rq_map_kern(q, rq, buffer, buflen, GFP_NOIO)) {
+	if (buflen && blk_rq_map_kern(rq, buffer, buflen, GFP_NOIO)) {
 		blk_put_request(rq);
 		sdev_printk(KERN_INFO, sdev,
 			    "%s: blk_rq_map_kern failed\n", __func__);
diff --git a/drivers/scsi/device_handler/scsi_dh_emc.c b/drivers/scsi/device_handler/scsi_dh_emc.c
index 0e572d2..dbbd56d 100644
--- a/drivers/scsi/device_handler/scsi_dh_emc.c
+++ b/drivers/scsi/device_handler/scsi_dh_emc.c
@@ -308,7 +308,7 @@ static struct request *get_req(struct scsi_device *sdev, int cmd,
 	rq->timeout = CLARIION_TIMEOUT;
 	rq->retries = CLARIION_RETRIES;
 
-	if (blk_rq_map_kern(rq->q, rq, buffer, len, GFP_NOIO)) {
+	if (blk_rq_map_kern(rq, buffer, len, GFP_NOIO)) {
 		blk_put_request(rq);
 		return NULL;
 	}
diff --git a/drivers/scsi/device_handler/scsi_dh_rdac.c b/drivers/scsi/device_handler/scsi_dh_rdac.c
index 5366476..f50b33a 100644
--- a/drivers/scsi/device_handler/scsi_dh_rdac.c
+++ b/drivers/scsi/device_handler/scsi_dh_rdac.c
@@ -219,7 +219,7 @@ static struct request *get_rdac_req(struct scsi_device *sdev,
 		return NULL;
 	}
 
-	if (buflen && blk_rq_map_kern(q, rq, buffer, buflen, GFP_NOIO)) {
+	if (buflen && blk_rq_map_kern(rq, buffer, buflen, GFP_NOIO)) {
 		blk_put_request(rq);
 		sdev_printk(KERN_INFO, sdev,
 				"get_rdac_req: blk_rq_map_kern failed.\n");
diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index 3fa5589..66c3d0b 100644
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -216,8 +216,7 @@ int scsi_execute(struct scsi_device *sdev, const unsigned char *cmd,
 
 	req = blk_get_request(sdev->request_queue, write, __GFP_WAIT);
 
-	if (bufflen &&	blk_rq_map_kern(sdev->request_queue, req,
-					buffer, bufflen, __GFP_WAIT))
+	if (bufflen && blk_rq_map_kern(req, buffer, bufflen, __GFP_WAIT))
 		goto out;
 
 	req->cmd_len = COMMAND_SIZE(cmd[0]);
@@ -332,9 +331,9 @@ int scsi_execute_async(struct scsi_device *sdev, const unsigned char *cmd,
 	req->cmd_flags |= REQ_QUIET;
 
 	if (use_sg)
-		err = blk_rq_map_kern_sg(req->q, req, buffer, use_sg, gfp);
+		err = blk_rq_map_kern_sg(req, buffer, use_sg, gfp);
 	else if (bufflen)
-		err = blk_rq_map_kern(req->q, req, buffer, bufflen, gfp);
+		err = blk_rq_map_kern(req, buffer, bufflen, gfp);
 
 	if (err)
 		goto free_req;
diff --git a/drivers/scsi/scsi_tgt_lib.c b/drivers/scsi/scsi_tgt_lib.c
index 48ba413..55beba4 100644
--- a/drivers/scsi/scsi_tgt_lib.c
+++ b/drivers/scsi/scsi_tgt_lib.c
@@ -357,12 +357,11 @@ static int scsi_tgt_transfer_response(struct scsi_cmnd *cmd)
 static int scsi_map_user_pages(struct scsi_tgt_cmd *tcmd, struct scsi_cmnd *cmd,
 			       unsigned long uaddr, unsigned int len, int rw)
 {
-	struct request_queue *q = cmd->request->q;
 	struct request *rq = cmd->request;
 	int err;
 
 	dprintk("%lx %u\n", uaddr, len);
-	err = blk_rq_map_user(q, rq, NULL, (void *)uaddr, len, GFP_KERNEL);
+	err = blk_rq_map_user(rq, NULL, (void *)uaddr, len, GFP_KERNEL);
 	if (err) {
 		/*
 		 * TODO: need to fixup sg_tablesize, max_segment_size,
diff --git a/drivers/scsi/sg.c b/drivers/scsi/sg.c
index 5fcf436..a769041 100644
--- a/drivers/scsi/sg.c
+++ b/drivers/scsi/sg.c
@@ -1672,11 +1672,11 @@ static int sg_start_req(Sg_request *srp, unsigned char *cmd)
 	}
 
 	if (iov_count)
-		res = blk_rq_map_user_iov(q, rq, md, hp->dxferp, iov_count,
+		res = blk_rq_map_user_iov(rq, md, hp->dxferp, iov_count,
 					  GFP_ATOMIC);
 	else
-		res = blk_rq_map_user(q, rq, md, hp->dxferp,
-				      hp->dxfer_len, GFP_ATOMIC);
+		res = blk_rq_map_user(rq, md, hp->dxferp, hp->dxfer_len,
+				      GFP_ATOMIC);
 
 	if (!res) {
 		srp->bio = rq->bio;
diff --git a/drivers/scsi/st.c b/drivers/scsi/st.c
index c6f19ee..c4615bb 100644
--- a/drivers/scsi/st.c
+++ b/drivers/scsi/st.c
@@ -492,8 +492,7 @@ static int st_scsi_execute(struct st_request *SRpnt, const unsigned char *cmd,
 	mdata->null_mapped = 1;
 
 	if (bufflen) {
-		err = blk_rq_map_user(req->q, req, mdata, NULL, bufflen,
-				      GFP_KERNEL);
+		err = blk_rq_map_user(req, mdata, NULL, bufflen, GFP_KERNEL);
 		if (err) {
 			blk_put_request(req);
 			return DRIVER_ERROR << 24;
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 6876466..ff0ad9e 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -770,15 +770,14 @@ extern void __blk_stop_queue(struct request_queue *q);
 extern void __blk_run_queue(struct request_queue *);
 extern void blk_run_queue(struct request_queue *);
 extern void blk_start_queueing(struct request_queue *);
-extern int blk_rq_map_user(struct request_queue *, struct request *,
-			   struct rq_map_data *, void __user *, unsigned long,
-			   gfp_t);
+extern int blk_rq_map_user(struct request *rq, struct rq_map_data *md,
+			   void __user *ubuf, unsigned long len, gfp_t gfp);
 extern int blk_rq_unmap_user(struct bio *);
-extern int blk_rq_map_kern(struct request_queue *, struct request *, void *, unsigned int, gfp_t);
-extern int blk_rq_map_user_iov(struct request_queue *q, struct request *rq,
-			       struct rq_map_data *md, struct iovec *iov,
-			       int count, gfp_t gfp);
-extern int blk_rq_map_kern_sg(struct request_queue *q, struct request *rq,
+extern int blk_rq_map_kern(struct request *rq, void *kbuf, unsigned int len,
+			   gfp_t gfp);
+extern int blk_rq_map_user_iov(struct request *rq, struct rq_map_data *md,
+			       struct iovec *iov, int count, gfp_t gfp);
+extern int blk_rq_map_kern_sg(struct request *rq,
 			      struct scatterlist *sgl, int nents, gfp_t gfp);
 extern int blk_execute_rq(struct request_queue *, struct gendisk *,
 			  struct request *, int);
-- 
1.6.0.2