nvme: refactor nvme_alloc_request

nvme_alloc_request expects a large number of parameters.
Split this out into two functions to reduce number of parameters.
First one retains the name nvme_alloc_request, while second one is
named nvme_map_user_request.

Signed-off-by: Kanchan Joshi <joshi.k@samsung.com>
Signed-off-by: Anuj Gupta <anuj20.g@samsung.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20220930062749.152261-8-anuj20.g@samsung.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

drivers/nvme/host/ioctl.c

@@ -70,54 +70,57 @@ static int nvme_finish_user_metadata(struct request *req, void __user *ubuf,
 }
 
 static struct request *nvme_alloc_user_request(struct request_queue *q,
-		struct nvme_command *cmd, void __user *ubuffer,
-		unsigned bufflen, void __user *meta_buffer, unsigned meta_len,
-		u32 meta_seed, void **metap, unsigned timeout, bool vec,
-		blk_opf_t rq_flags, blk_mq_req_flags_t blk_flags)
+		struct nvme_command *cmd, blk_opf_t rq_flags,
+		blk_mq_req_flags_t blk_flags)
 {
-	struct nvme_ns *ns = q->queuedata;
-	struct block_device *bdev = ns ? ns->disk->part0 : NULL;
 	struct request *req;
-	struct bio *bio = NULL;
-	void *meta = NULL;
-	int ret;
 
 	req = blk_mq_alloc_request(q, nvme_req_op(cmd) | rq_flags, blk_flags);
 	if (IS_ERR(req))
 		return req;
 	nvme_init_request(req, cmd);
-
-	if (timeout)
-		req->timeout = timeout;
 	nvme_req(req)->flags |= NVME_REQ_USERCMD;
+	return req;
+}
 
-	if (ubuffer && bufflen) {
-		ret = blk_rq_map_user_io(req, NULL, ubuffer, bufflen,
-				GFP_KERNEL, vec, 0, 0, rq_data_dir(req));
-		if (ret)
-			goto out;
-		bio = req->bio;
-		if (bdev)
-			bio_set_dev(bio, bdev);
-		if (bdev && meta_buffer && meta_len) {
-			meta = nvme_add_user_metadata(req, meta_buffer,
-					meta_len, meta_seed);
-			if (IS_ERR(meta)) {
-				ret = PTR_ERR(meta);
-				goto out_unmap;
-			}
-			*metap = meta;
+static int nvme_map_user_request(struct request *req, void __user *ubuffer,
+		unsigned bufflen, void __user *meta_buffer, unsigned meta_len,
+		u32 meta_seed, void **metap, bool vec)
+{
+	struct request_queue *q = req->q;
+	struct nvme_ns *ns = q->queuedata;
+	struct block_device *bdev = ns ? ns->disk->part0 : NULL;
+	struct bio *bio = NULL;
+	void *meta = NULL;
+	int ret;
+
+	ret = blk_rq_map_user_io(req, NULL, ubuffer, bufflen, GFP_KERNEL, vec,
+			0, 0, rq_data_dir(req));
+
+	if (ret)
+		goto out;
+	bio = req->bio;
+	if (bdev)
+		bio_set_dev(bio, bdev);
+
+	if (bdev && meta_buffer && meta_len) {
+		meta = nvme_add_user_metadata(req, meta_buffer, meta_len,
+				meta_seed);
+		if (IS_ERR(meta)) {
+			ret = PTR_ERR(meta);
+			goto out_unmap;
 		}
+		*metap = meta;
 	}
 
-	return req;
+	return ret;
 
 out_unmap:
 	if (bio)
 		blk_rq_unmap_user(bio);
 out:
 	blk_mq_free_request(req);
-	return ERR_PTR(ret);
+	return ret;
 }
 
 static int nvme_submit_user_cmd(struct request_queue *q,
@@ -132,11 +135,18 @@ static int nvme_submit_user_cmd(struct request_queue *q,
 	u32 effects;
 	int ret;
 
-	req = nvme_alloc_user_request(q, cmd, ubuffer, bufflen, meta_buffer,
-			meta_len, meta_seed, &meta, timeout, vec, 0, 0);
+	req = nvme_alloc_user_request(q, cmd, 0, 0);
 	if (IS_ERR(req))
 		return PTR_ERR(req);
 
+	req->timeout = timeout;
+	if (ubuffer && bufflen) {
+		ret = nvme_map_user_request(req, ubuffer, bufflen, meta_buffer,
+				meta_len, meta_seed, &meta, vec);
+		if (ret)
+			return ret;
+	}
+
 	bio = req->bio;
 	ctrl = nvme_req(req)->ctrl;
 
@@ -456,6 +466,7 @@ static int nvme_uring_cmd_io(struct nvme_ctrl *ctrl, struct nvme_ns *ns,
 	blk_opf_t rq_flags = 0;
 	blk_mq_req_flags_t blk_flags = 0;
 	void *meta = NULL;
+	int ret;
 
 	if (!capable(CAP_SYS_ADMIN))
 		return -EACCES;
@@ -495,13 +506,18 @@ static int nvme_uring_cmd_io(struct nvme_ctrl *ctrl, struct nvme_ns *ns,
 		rq_flags |= REQ_POLLED;
 
 retry:
-	req = nvme_alloc_user_request(q, &c, nvme_to_user_ptr(d.addr),
-			d.data_len, nvme_to_user_ptr(d.metadata),
-			d.metadata_len, 0, &meta, d.timeout_ms ?
-			msecs_to_jiffies(d.timeout_ms) : 0, vec, rq_flags,
-			blk_flags);
+	req = nvme_alloc_user_request(q, &c, rq_flags, blk_flags);
 	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, nvme_to_user_ptr(d.addr),
+			d.data_len, nvme_to_user_ptr(d.metadata),
+			d.metadata_len, 0, &meta, vec);
+		if (ret)
+			return ret;
+	}
 
 	if (issue_flags & IO_URING_F_IOPOLL && rq_flags & REQ_POLLED) {
 		if (unlikely(!req->bio)) {