[PATCH v4 07/19] ublk: inline ublk_check_and_get_req() into ublk_user_copy()

[Caleb Sander Mateos <csander@purestorage.com>]

ublk_check_and_get_req() has a single callsite in ublk_user_copy(). It
takes a ton of arguments in order to pass local variables from
ublk_user_copy() to ublk_check_and_get_req() and vice versa. And more
are about to be added. Combine the functions to reduce the argument
passing noise.

Signed-off-by: Caleb Sander Mateos <csander@purestorage.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
---
 drivers/block/ublk_drv.c | 51 ++++++++++++++--------------------------
 1 file changed, 18 insertions(+), 33 deletions(-)

diff --git a/drivers/block/ublk_drv.c b/drivers/block/ublk_drv.c
index 225372cca404..e7697dc4a812 100644
--- a/drivers/block/ublk_drv.c
+++ b/drivers/block/ublk_drv.c
@@ -2655,70 +2655,55 @@ static inline bool ublk_check_ubuf_dir(const struct request *req,
 		return true;
 
 	return false;
 }
 
-static struct request *ublk_check_and_get_req(struct kiocb *iocb,
-		struct iov_iter *iter, size_t *off, int dir,
-		struct ublk_io **io)
+static ssize_t
+ublk_user_copy(struct kiocb *iocb, struct iov_iter *iter, int dir)
 {
 	struct ublk_device *ub = iocb->ki_filp->private_data;
 	struct ublk_queue *ubq;
 	struct request *req;
+	struct ublk_io *io;
 	size_t buf_off;
 	u16 tag, q_id;
+	ssize_t ret;
 
 	if (!user_backed_iter(iter))
-		return ERR_PTR(-EACCES);
+		return -EACCES;
 
 	if (ub->dev_info.state == UBLK_S_DEV_DEAD)
-		return ERR_PTR(-EACCES);
+		return -EACCES;
 
 	tag = ublk_pos_to_tag(iocb->ki_pos);
 	q_id = ublk_pos_to_hwq(iocb->ki_pos);
 	buf_off = ublk_pos_to_buf_off(iocb->ki_pos);
 
 	if (q_id >= ub->dev_info.nr_hw_queues)
-		return ERR_PTR(-EINVAL);
+		return -EINVAL;
 
 	ubq = ublk_get_queue(ub, q_id);
 	if (!ublk_dev_support_user_copy(ub))
-		return ERR_PTR(-EACCES);
+		return -EACCES;
 
 	if (tag >= ub->dev_info.queue_depth)
-		return ERR_PTR(-EINVAL);
+		return -EINVAL;
 
-	*io = &ubq->ios[tag];
-	req = __ublk_check_and_get_req(ub, q_id, tag, *io, buf_off);
+	io = &ubq->ios[tag];
+	req = __ublk_check_and_get_req(ub, q_id, tag, io, buf_off);
 	if (!req)
-		return ERR_PTR(-EINVAL);
-
-	if (!ublk_check_ubuf_dir(req, dir))
-		goto fail;
-
-	*off = buf_off;
-	return req;
-fail:
-	ublk_put_req_ref(*io, req);
-	return ERR_PTR(-EACCES);
-}
-
-static ssize_t
-ublk_user_copy(struct kiocb *iocb, struct iov_iter *iter, int dir)
-{
-	struct request *req;
-	struct ublk_io *io;
-	size_t buf_off;
-	size_t ret;
+		return -EINVAL;
 
-	req = ublk_check_and_get_req(iocb, iter, &buf_off, dir, &io);
-	if (IS_ERR(req))
-		return PTR_ERR(req);
+	if (!ublk_check_ubuf_dir(req, dir)) {
+		ret = -EACCES;
+		goto out;
+	}
 
 	ret = ublk_copy_user_pages(req, buf_off, iter, dir);
-	ublk_put_req_ref(io, req);
 
+out:
+	ublk_put_req_ref(io, req);
 	return ret;
 }
 
 static ssize_t ublk_ch_read_iter(struct kiocb *iocb, struct iov_iter *to)
 {
-- 
2.45.2