[PATCH 3/3] nvme/ioctl: move fixed buffer lookup to nvme_uring_cmd_io()

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

nvme_map_user_request() is called from both nvme_submit_user_cmd() and
nvme_uring_cmd_io(). But the ioucmd branch is only applicable to
nvme_uring_cmd_io(). Move it to nvme_uring_cmd_io() and just pass the
resulting iov_iter to nvme_map_user_request().

Signed-off-by: Caleb Sander Mateos <csander@purestorage.com>
---
 drivers/nvme/host/ioctl.c | 40 +++++++++++++++++++++------------------
 1 file changed, 22 insertions(+), 18 deletions(-)

diff --git a/drivers/nvme/host/ioctl.c b/drivers/nvme/host/ioctl.c
index 843371e6e1e2..feac2c2b33e1 100644
--- a/drivers/nvme/host/ioctl.c
+++ b/drivers/nvme/host/ioctl.c
@@ -112,11 +112,11 @@ static struct request *nvme_alloc_user_request(struct request_queue *q,
 	return req;
 }
 
 static int nvme_map_user_request(struct request *req, u64 ubuffer,
 		unsigned bufflen, void __user *meta_buffer, unsigned meta_len,
-		struct io_uring_cmd *ioucmd, unsigned int flags)
+		struct iov_iter *iter, unsigned int flags)
 {
 	struct request_queue *q = req->q;
 	struct nvme_ns *ns = q->queuedata;
 	struct block_device *bdev = ns ? ns->disk->part0 : NULL;
 	bool supports_metadata = bdev && blk_get_integrity(bdev->bd_disk);
@@ -134,27 +134,16 @@ static int nvme_map_user_request(struct request *req, u64 ubuffer,
 		if (!nvme_ctrl_meta_sgl_supported(ctrl))
 			dev_warn_once(ctrl->device,
 				      "using unchecked metadata buffer\n");
 	}
 
-	if (ioucmd && (ioucmd->flags & IORING_URING_CMD_FIXED)) {
-		struct iov_iter iter;
-
-		/* fixedbufs is only for non-vectored io */
-		if (flags & NVME_IOCTL_VEC)
-			return -EINVAL;
-
-		ret = io_uring_cmd_import_fixed(ubuffer, bufflen,
-				rq_data_dir(req), &iter, ioucmd);
-		if (ret < 0)
-			return ret;
-		ret = blk_rq_map_user_iov(q, req, NULL, &iter, GFP_KERNEL);
-	} else {
+	if (iter)
+		ret = blk_rq_map_user_iov(q, req, NULL, iter, GFP_KERNEL);
+	else
 		ret = blk_rq_map_user_io(req, NULL, nvme_to_user_ptr(ubuffer),
 				bufflen, GFP_KERNEL, flags & NVME_IOCTL_VEC, 0,
 				0, rq_data_dir(req));
-	}
 
 	if (ret)
 		return ret;
 
 	bio = req->bio;
@@ -511,13 +500,28 @@ static int nvme_uring_cmd_io(struct nvme_ctrl *ctrl, struct nvme_ns *ns,
 	if (IS_ERR(req))
 		return PTR_ERR(req);
 	req->timeout = d.timeout_ms ? msecs_to_jiffies(d.timeout_ms) : 0;
 
 	if (d.addr && d.data_len) {
-		ret = nvme_map_user_request(req, d.addr,
-			d.data_len, nvme_to_user_ptr(d.metadata),
-			d.metadata_len, ioucmd, vec);
+		struct iov_iter iter;
+		struct iov_iter *map_iter = NULL;
+
+		if (ioucmd->flags & IORING_URING_CMD_FIXED) {
+			/* fixedbufs is only for non-vectored io */
+			if (vec) {
+				ret = -EINVAL;
+				goto out_free_req;
+			}
+
+			ret = io_uring_cmd_import_fixed(d.addr, d.data_len,
+					rq_data_dir(req), &iter, ioucmd);
+			if (ret < 0)
+				goto out_free_req;
+		}
+		ret = nvme_map_user_request(req, d.addr, d.data_len,
+			nvme_to_user_ptr(d.metadata), d.metadata_len,
+			map_iter, vec);
 		if (ret)
 			goto out_free_req;
 	}
 
 	/* to free bio on completion, as req->bio will be null at that time */
-- 
2.45.2