[PATCH v5 3/6] nvme: refactor nvme_submit_user_cmd()

Kanchan Joshi
2022-05-11T06:32:13Z

From: Christoph Hellwig <hch@lst.de>

Divide the work into two helpers, namely nvme_alloc_user_request and
nvme_execute_user_rq. This is a prep patch, to help wiring up
uring-cmd support in nvme.

Signed-off-by: Christoph Hellwig <hch@lst.de>
[axboe: fold in fix for assuming bio is non-NULL]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
---
drivers/nvme/host/ioctl.c | 56 +++++++++++++++++++++++++++++++--------
1 file changed, 45 insertions(+), 11 deletions(-)

diff --git a/drivers/nvme/host/ioctl.c b/drivers/nvme/host/ioctl.c
index 554566371ffa..8d2569b656cc 100644
--- a/drivers/nvme/host/ioctl.c
+++ b/drivers/nvme/host/ioctl.c
@@ -53,10 +53,20 @@ static void *nvme_add_user_metadata(struct bio *bio, void __user *ubuf,
return ERR_PTR(ret);
}

-static int nvme_submit_user_cmd(struct request_queue *q,
+static int nvme_finish_user_metadata(struct request *req, void __user *ubuf,
+ void *meta, unsigned len, int ret)
+{
+ if (!ret && req_op(req) == REQ_OP_DRV_IN &&
+ copy_to_user(ubuf, meta, len))
+ ret = -EFAULT;
+ kfree(meta);
+ return ret;
+}
+
+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, u64 *result, unsigned timeout, bool vec)
+ u32 meta_seed, void **metap, unsigned timeout, bool vec)
{
bool write = nvme_is_write(cmd);
struct nvme_ns *ns = q->queuedata;
@@ -68,7 +78,7 @@ static int nvme_submit_user_cmd(struct request_queue *q,

req = blk_mq_alloc_request(q, nvme_req_op(cmd), 0);
if (IS_ERR(req))
- return PTR_ERR(req);
+ return req;
nvme_init_request(req, cmd);

if (timeout)
@@ -105,26 +115,50 @@ static int nvme_submit_user_cmd(struct request_queue *q,
goto out_unmap;
}
req->cmd_flags |= REQ_INTEGRITY;
+ *metap = meta;
}
}

+ return req;
+
+out_unmap:
+ if (bio)
+ blk_rq_unmap_user(bio);
+out:
+ blk_mq_free_request(req);
+ return ERR_PTR(ret);
+}
+
+static int nvme_submit_user_cmd(struct request_queue *q,
+ struct nvme_command *cmd, void __user *ubuffer,
+ unsigned bufflen, void __user *meta_buffer, unsigned meta_len,
+ u32 meta_seed, u64 *result, unsigned timeout, bool vec)
+{
+ struct request *req;
+ void *meta = NULL;
+ struct bio *bio;
+ int ret;
+
+ req = nvme_alloc_user_request(q, cmd, ubuffer, bufflen, meta_buffer,
+ meta_len, meta_seed, &meta, timeout, vec);
+ if (IS_ERR(req))
+ return PTR_ERR(req);
+
+ bio = req->bio;
+
ret = nvme_execute_passthru_rq(req);
+
if (result)
*result = le64_to_cpu(nvme_req(req)->result.u64);
- if (meta && !ret && !write) {
- if (copy_to_user(meta_buffer, meta, meta_len))
- ret = -EFAULT;
- }
- kfree(meta);
- out_unmap:
+ if (meta)
+ ret = nvme_finish_user_metadata(req, meta_buffer, meta,
+ meta_len, ret);
if (bio)
blk_rq_unmap_user(bio);
- out:
blk_mq_free_request(req);
return ret;
}

-
static int nvme_submit_io(struct nvme_ns *ns, struct nvme_user_io __user *uio)
{
struct nvme_user_io io;
--
2.25.1