[PATCH for-next v8 3/5] nvme: refactor nvme_alloc_user_request

[Kanchan Joshi <joshi.k@samsung.com>]

Separate this out to two functions with reduced number of arguments.
While at it, do bit of refactoring in nvme_add_user_metadata too.
_
Signed-off-by: Kanchan Joshi <joshi.k@samsung.com>
---
 drivers/nvme/host/ioctl.c | 132 +++++++++++++++++++++-----------------
 1 file changed, 74 insertions(+), 58 deletions(-)

diff --git a/drivers/nvme/host/ioctl.c b/drivers/nvme/host/ioctl.c
index 548aca8b5b9f..9537991deac9 100644
--- a/drivers/nvme/host/ioctl.c
+++ b/drivers/nvme/host/ioctl.c
@@ -20,19 +20,20 @@ static void __user *nvme_to_user_ptr(uintptr_t ptrval)
 	return (void __user *)ptrval;
 }
 
-static void *nvme_add_user_metadata(struct bio *bio, void __user *ubuf,
-		unsigned len, u32 seed, bool write)
+static void *nvme_add_user_metadata(struct request *req, void __user *ubuf,
+		unsigned len, u32 seed)
 {
 	struct bio_integrity_payload *bip;
 	int ret = -ENOMEM;
 	void *buf;
+	struct bio *bio = req->bio;
 
 	buf = kmalloc(len, GFP_KERNEL);
 	if (!buf)
 		goto out;
 
 	ret = -EFAULT;
-	if (write && copy_from_user(buf, ubuf, len))
+	if ((req_op(req) == REQ_OP_DRV_OUT) && copy_from_user(buf, ubuf, len))
 		goto out_free_meta;
 
 	bip = bio_integrity_alloc(bio, GFP_KERNEL, 1);
@@ -45,8 +46,10 @@ static void *nvme_add_user_metadata(struct bio *bio, void __user *ubuf,
 	bip->bip_iter.bi_sector = seed;
 	ret = bio_integrity_add_page(bio, virt_to_page(buf), len,
 			offset_in_page(buf));
-	if (ret == len)
+	if (ret == len) {
+		req->cmd_flags |= REQ_INTEGRITY;
 		return buf;
+	}
 	ret = -ENOMEM;
 out_free_meta:
 	kfree(buf);
@@ -65,70 +68,67 @@ 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)
 {
-	bool write = nvme_is_write(cmd);
-	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) {
-		if (!vec)
-			ret = blk_rq_map_user(q, req, NULL, ubuffer, bufflen,
-				GFP_KERNEL);
-		else {
-			struct iovec fast_iov[UIO_FASTIOV];
-			struct iovec *iov = fast_iov;
-			struct iov_iter iter;
-
-			ret = import_iovec(rq_data_dir(req), ubuffer, bufflen,
-					UIO_FASTIOV, &iov, &iter);
-			if (ret < 0)
-				goto out;
-			ret = blk_rq_map_user_iov(q, req, NULL, &iter,
-					GFP_KERNEL);
-			kfree(iov);
-		}
-		if (ret)
+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;
+
+	if (!vec)
+		ret = blk_rq_map_user(q, req, NULL, ubuffer, bufflen,
+			GFP_KERNEL);
+	else {
+		struct iovec fast_iov[UIO_FASTIOV];
+		struct iovec *iov = fast_iov;
+		struct iov_iter iter;
+
+		ret = import_iovec(rq_data_dir(req), ubuffer, bufflen,
+				UIO_FASTIOV, &iov, &iter);
+		if (ret < 0)
 			goto out;
-		bio = req->bio;
-		if (bdev)
-			bio_set_dev(bio, bdev);
-		if (bdev && meta_buffer && meta_len) {
-			meta = nvme_add_user_metadata(bio, meta_buffer, meta_len,
-					meta_seed, write);
-			if (IS_ERR(meta)) {
-				ret = PTR_ERR(meta);
-				goto out_unmap;
-			}
-			req->cmd_flags |= REQ_INTEGRITY;
-			*metap = meta;
+		ret = blk_rq_map_user_iov(q, req, NULL, &iter, GFP_KERNEL);
+		kfree(iov);
+	}
+	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,
@@ -141,13 +141,19 @@ static int nvme_submit_user_cmd(struct request_queue *q,
 	struct bio *bio;
 	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);
 
-	bio = req->bio;
+	req->timeout = timeout;
+	if (ubuffer && bufflen) {
+		ret = nvme_map_user_request(req, ubuffer, bufflen, meta_buffer,
+			meta_len, meta_seed, &meta, vec);
+		if (ret)
+			goto out;
+	}
 
+	bio = req->bio;
 	ret = nvme_execute_passthru_rq(req);
 
 	if (result)
@@ -157,6 +163,7 @@ static int nvme_submit_user_cmd(struct request_queue *q,
 						meta_len, ret);
 	if (bio)
 		blk_rq_unmap_user(bio);
+out:
 	blk_mq_free_request(req);
 	return ret;
 }
@@ -418,6 +425,7 @@ 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;
@@ -457,13 +465,18 @@ 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)
+			goto out_err;
+	}
 	req->end_io = nvme_uring_cmd_end_io;
 	req->end_io_data = ioucmd;
 
@@ -486,6 +499,9 @@ static int nvme_uring_cmd_io(struct nvme_ctrl *ctrl, struct nvme_ns *ns,
 
 	blk_execute_rq_nowait(req, false);
 	return -EIOCBQUEUED;
+out_err:
+	blk_mq_free_request(req);
+	return ret;
 }
 
 static bool is_ctrl_ioctl(unsigned int cmd)
-- 
2.25.1