[PATCH] nvme: return the whole CQE through the request passthrough interface

[m@bjorling.me (Matias Bjørling)]

On 02/08/2016 07:09 PM, Christoph Hellwig wrote:
> Both LighNVM and NVMe over Fabrics need to look at more than just the
> status and result field.
> 
> Signed-off-by: Christoph Hellwig <hch at lst.de>
> Reviewed-by: Sagi Grimberg <sagig at mellanox.com>
> Reviewed-by: Jay Freyensee <james.p.freyensee at intel.com>
> Signed-off-by: Sagi Grimberg <sagig at mellanox.com>
> ---
>  drivers/nvme/host/core.c | 27 +++++++++++++++++++--------
>  drivers/nvme/host/nvme.h |  3 ++-
>  drivers/nvme/host/pci.c  | 10 +++-------
>  3 files changed, 24 insertions(+), 16 deletions(-)
> 
> diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c
> index c326931..6715bbf 100644
> --- a/drivers/nvme/host/core.c
> +++ b/drivers/nvme/host/core.c
> @@ -107,7 +107,6 @@ struct request *nvme_alloc_request(struct request_queue *q,
>  
>  	req->cmd = (unsigned char *)cmd;
>  	req->cmd_len = sizeof(struct nvme_command);
> -	req->special = (void *)0;
>  
>  	return req;
>  }
> @@ -117,7 +116,8 @@ struct request *nvme_alloc_request(struct request_queue *q,
>   * if the result is positive, it's an NVM Express status code
>   */
>  int __nvme_submit_sync_cmd(struct request_queue *q, struct nvme_command *cmd,
> -		void *buffer, unsigned bufflen, u32 *result, unsigned timeout)
> +		struct nvme_completion *cqe, void *buffer, unsigned bufflen,
> +		unsigned timeout)
>  {
>  	struct request *req;
>  	int ret;
> @@ -127,6 +127,7 @@ int __nvme_submit_sync_cmd(struct request_queue *q, struct nvme_command *cmd,
>  		return PTR_ERR(req);
>  
>  	req->timeout = timeout ? timeout : ADMIN_TIMEOUT;
> +	req->special = cqe;
>  
>  	if (buffer && bufflen) {
>  		ret = blk_rq_map_kern(q, req, buffer, bufflen, GFP_KERNEL);
> @@ -135,8 +136,6 @@ int __nvme_submit_sync_cmd(struct request_queue *q, struct nvme_command *cmd,
>  	}
>  
>  	blk_execute_rq(req->q, NULL, req, 0);
> -	if (result)
> -		*result = (u32)(uintptr_t)req->special;
>  	ret = req->errors;
>   out:
>  	blk_mq_free_request(req);
> @@ -146,7 +145,7 @@ int __nvme_submit_sync_cmd(struct request_queue *q, struct nvme_command *cmd,
>  int nvme_submit_sync_cmd(struct request_queue *q, struct nvme_command *cmd,
>  		void *buffer, unsigned bufflen)
>  {
> -	return __nvme_submit_sync_cmd(q, cmd, buffer, bufflen, NULL, 0);
> +	return __nvme_submit_sync_cmd(q, cmd, NULL, buffer, bufflen, 0);
>  }
>  
>  int __nvme_submit_user_cmd(struct request_queue *q, struct nvme_command *cmd,
> @@ -155,6 +154,7 @@ int __nvme_submit_user_cmd(struct request_queue *q, struct nvme_command *cmd,
>  		u32 *result, unsigned timeout)
>  {
>  	bool write = cmd->common.opcode & 1;
> +	struct nvme_completion cqe;
>  	struct nvme_ns *ns = q->queuedata;
>  	struct gendisk *disk = ns ? ns->disk : NULL;
>  	struct request *req;
> @@ -167,6 +167,7 @@ int __nvme_submit_user_cmd(struct request_queue *q, struct nvme_command *cmd,
>  		return PTR_ERR(req);
>  
>  	req->timeout = timeout ? timeout : ADMIN_TIMEOUT;
> +	req->special = &cqe;
>  
>  	if (ubuffer && bufflen) {
>  		ret = blk_rq_map_user(q, req, NULL, ubuffer, bufflen,
> @@ -221,7 +222,7 @@ int __nvme_submit_user_cmd(struct request_queue *q, struct nvme_command *cmd,
>  	blk_execute_rq(req->q, disk, req, 0);
>  	ret = req->errors;
>  	if (result)
> -		*result = (u32)(uintptr_t)req->special;
> +		*result = le32_to_cpu(cqe.result);
>  	if (meta && !ret && !write) {
>  		if (copy_to_user(meta_buffer, meta, meta_len))
>  			ret = -EFAULT;
> @@ -302,6 +303,8 @@ int nvme_get_features(struct nvme_ctrl *dev, unsigned fid, unsigned nsid,
>  					dma_addr_t dma_addr, u32 *result)
>  {
>  	struct nvme_command c;
> +	struct nvme_completion cqe;
> +	int ret;
>  
>  	memset(&c, 0, sizeof(c));
>  	c.features.opcode = nvme_admin_get_features;
> @@ -309,13 +312,18 @@ int nvme_get_features(struct nvme_ctrl *dev, unsigned fid, unsigned nsid,
>  	c.features.prp1 = cpu_to_le64(dma_addr);
>  	c.features.fid = cpu_to_le32(fid);
>  
> -	return __nvme_submit_sync_cmd(dev->admin_q, &c, NULL, 0, result, 0);
> +	ret = __nvme_submit_sync_cmd(dev->admin_q, &c, &cqe, NULL, 0, 0);
> +	if (ret >= 0)
> +		*result = le32_to_cpu(cqe.result);
> +	return ret;
>  }
>  
>  int nvme_set_features(struct nvme_ctrl *dev, unsigned fid, unsigned dword11,
>  					dma_addr_t dma_addr, u32 *result)
>  {
>  	struct nvme_command c;
> +	struct nvme_completion cqe;
> +	int ret;
>  
>  	memset(&c, 0, sizeof(c));
>  	c.features.opcode = nvme_admin_set_features;
> @@ -323,7 +331,10 @@ int nvme_set_features(struct nvme_ctrl *dev, unsigned fid, unsigned dword11,
>  	c.features.fid = cpu_to_le32(fid);
>  	c.features.dword11 = cpu_to_le32(dword11);
>  
> -	return __nvme_submit_sync_cmd(dev->admin_q, &c, NULL, 0, result, 0);
> +	ret = __nvme_submit_sync_cmd(dev->admin_q, &c, &cqe, NULL, 0, 0);
> +	if (ret >= 0)
> +		*result = le32_to_cpu(cqe.result);
> +	return ret;
>  }
>  
>  int nvme_get_log_page(struct nvme_ctrl *dev, struct nvme_smart_log **log)
> diff --git a/drivers/nvme/host/nvme.h b/drivers/nvme/host/nvme.h
> index 4fb5bb7..d85997f 100644
> --- a/drivers/nvme/host/nvme.h
> +++ b/drivers/nvme/host/nvme.h
> @@ -247,7 +247,8 @@ void nvme_requeue_req(struct request *req);
>  int nvme_submit_sync_cmd(struct request_queue *q, struct nvme_command *cmd,
>  		void *buf, unsigned bufflen);
>  int __nvme_submit_sync_cmd(struct request_queue *q, struct nvme_command *cmd,
> -		void *buffer, unsigned bufflen,  u32 *result, unsigned timeout);
> +		struct nvme_completion *cqe, void *buffer, unsigned bufflen,
> +		unsigned timeout);
>  int nvme_submit_user_cmd(struct request_queue *q, struct nvme_command *cmd,
>  		void __user *ubuffer, unsigned bufflen, u32 *result,
>  		unsigned timeout);
> diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c
> index 72ef832..f8ae20c 100644
> --- a/drivers/nvme/host/pci.c
> +++ b/drivers/nvme/host/pci.c
> @@ -759,10 +759,8 @@ static void __nvme_process_cq(struct nvme_queue *nvmeq, unsigned int *tag)
>  		}
>  
>  		req = blk_mq_tag_to_rq(*nvmeq->tags, cqe.command_id);
> -		if (req->cmd_type == REQ_TYPE_DRV_PRIV) {
> -			u32 result = le32_to_cpu(cqe.result);
> -			req->special = (void *)(uintptr_t)result;
> -		}
> +		if (req->cmd_type == REQ_TYPE_DRV_PRIV && req->special)
> +			memcpy(req->special, &cqe, sizeof(cqe));
>  		blk_mq_complete_request(req, status >> 1);
>  
>  	}
> @@ -905,12 +903,10 @@ static void abort_endio(struct request *req, int error)
>  {
>  	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
>  	struct nvme_queue *nvmeq = iod->nvmeq;
> -	u32 result = (u32)(uintptr_t)req->special;
>  	u16 status = req->errors;
>  
> -	dev_warn(nvmeq->q_dmadev, "Abort status:%x result:%x", status, result);
> +	dev_warn(nvmeq->q_dmadev, "Abort status 0x%x\n", status);
>  	atomic_inc(&nvmeq->dev->ctrl.abort_limit);
> -
>  	blk_mq_free_request(req);
>  }
>  
> 

Thanks.

Reviewed-by: Matias Bj?rling <m at bjorling.me>