[PATCH v2 2/6] nvme-core: introduce complete failed request

[Hannes Reinecke]

On 1/7/21 4:31 AM, Chao Leng wrote:
> When a request is queued failed, if the fail status is not
> BLK_STS_RESOURCE, BLK_STS_DEV_RESOURCE, BLK_STS_ZONE_RESOURCE,
> the request is need to complete with nvme_complete_rq in queue_rq.
> So introduce nvme_try_complete_failed_req.
> The request is needed to complete with NVME_SC_HOST_PATH_ERROR in
> nvmf_fail_nonready_command and queue_rq.
> So introduce nvme_complete_failed_req.
> For details, see the subsequent patches.
> 
> Signed-off-by: Chao Leng <lengchao at huawei.com>
> ---
>   drivers/nvme/host/nvme.h | 21 +++++++++++++++++++++
>   1 file changed, 21 insertions(+)
> 
> diff --git a/drivers/nvme/host/nvme.h b/drivers/nvme/host/nvme.h
> index bfcedfa4b057..fc4eefdfbb34 100644
> --- a/drivers/nvme/host/nvme.h
> +++ b/drivers/nvme/host/nvme.h
> @@ -649,6 +649,27 @@ void nvme_put_ns_from_disk(struct nvme_ns_head *head, int idx);
>   extern const struct attribute_group *nvme_ns_id_attr_groups[];
>   extern const struct block_device_operations nvme_ns_head_ops;
>   
> +static inline void nvme_complete_failed_req(struct request *req)
> +{
> +	nvme_req(req)->status = NVME_SC_HOST_PATH_ERROR;
> +	blk_mq_set_request_complete(req);
> +	nvme_complete_rq(req);
> +}
> +
> +static inline blk_status_t nvme_try_complete_failed_req(struct request *req,
> +							blk_status_t ret)
> +{
> +	switch (ret) {
> +	case BLK_STS_RESOURCE:
> +	case BLK_STS_DEV_RESOURCE:
> +	case BLK_STS_ZONE_RESOURCE:
> +		return ret;
> +	default:
> +		nvme_complete_failed_req(req);
> +		return BLK_STS_OK;
> +	}
> +}
> +
>   #ifdef CONFIG_NVME_MULTIPATH
>   static inline bool nvme_ctrl_use_ana(struct nvme_ctrl *ctrl)
>   {
> 
This is not correct.
HOST_PATH_ERROR only should be set _iff_ it is a pathing issue, and the 
HBA/transport is equipped to determine that.
Any other error have other causes, and we need to look at the individual 
error codes (and situations) to determine if this really is a pathing error.

Cheers,

Hannes
-- 
Dr. Hannes Reinecke                Kernel Storage Architect
hare at suse.de                              +49 911 74053 688
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