net/iavf: fix PF returning error

  When the command sent by VF to PF fails, iavf may need to run
different code paths according to the specific reason of the
failure (not supported or other reasons).

This patch adds support of identifying PF return error type.

Fixes: 22b123a36d07 ("net/avf: initialize PMD")
Cc: stable@dpdk.org

Signed-off-by: Alvin Zhang <alvinx.zhang@intel.com>
---
 drivers/net/iavf/iavf_vchnl.c | 18 ++++++++++++------
 1 file changed, 12 insertions(+), 6 deletions(-)
  

> -----Original Message-----
> From: Zhang, AlvinX <alvinx.zhang@intel.com>
> Sent: Sunday, April 25, 2021 1:05 PM
> To: Wu, Jingjing <jingjing.wu@intel.com>; Xing, Beilei <beilei.xing@intel.com>
> Cc: dev@dpdk.org; Zhang, AlvinX <alvinx.zhang@intel.com>; stable@dpdk.org
> Subject: [PATCH] net/iavf: fix PF returning error
> 
> When the command sent by VF to PF fails, iavf may need to run different code
> paths according to the specific reason of the failure (not supported or other
> reasons).
> 
> This patch adds support of identifying PF return error type.
> 
> Fixes: 22b123a36d07 ("net/avf: initialize PMD")
> Cc: stable@dpdk.org
> 
> Signed-off-by: Alvin Zhang <alvinx.zhang@intel.com>
> ---
>  drivers/net/iavf/iavf_vchnl.c | 18 ++++++++++++------
>  1 file changed, 12 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/net/iavf/iavf_vchnl.c b/drivers/net/iavf/iavf_vchnl.c index
> 45096cb..6586fc3 100644
> --- a/drivers/net/iavf/iavf_vchnl.c
> +++ b/drivers/net/iavf/iavf_vchnl.c
> @@ -228,13 +228,19 @@
>  			rte_delay_ms(ASQ_DELAY_MS);
>  			/* If don't read msg or read sys event, continue */
>  		} while (i++ < MAX_TRY_TIMES);
> -		/* If there's no response is received, clear command */
> -		if (i >= MAX_TRY_TIMES  ||
> -		    vf->cmd_retval != VIRTCHNL_STATUS_SUCCESS) {
> -			err = -1;
> -			PMD_DRV_LOG(ERR, "No response or return failure
> (%d)"
> -				    " for cmd %d", vf->cmd_retval, args->ops);
> +
> +		if (i >= MAX_TRY_TIMES) {
> +			PMD_DRV_LOG(ERR, "No response for cmd %d", args-
> >ops);
>  			_clear_cmd(vf);
> +			err = -EIO;
> +		} else if (vf->cmd_retval ==
> +			   (uint32_t)VIRTCHNL_STATUS_ERR_NOT_SUPPORTED)

Can we change 'uint32_t cmd_retval' to 'enum virtchnl_status_code cmd_retval' in iavf_info structure? Then we needn't cast here.

> {
> +			PMD_DRV_LOG(ERR, "Cmd %d not supported", args-
> >ops);
> +			err = -ENOTSUP;
> +		} else if (vf->cmd_retval != VIRTCHNL_STATUS_SUCCESS) {
> +			PMD_DRV_LOG(ERR, "Return failure %d for cmd %d",
> +				    vf->cmd_retval, args->ops);
> +			err = -EINVAL;
>  		}
>  		break;
>  	}
> --
> 1.8.3.1