Re: [dpdk-dev] [PATCH v2] net/ixgbe: check jumbo frame enable parameter

["Zhao1, Wei" <wei.zhao1@intel.com>]

Add the background for this patch.
https://mails.dpdk.org/archives/dev/2018-November/117771.html
https://mails.dpdk.org/archives/dev/2018-November/117772.html



> -----Original Message-----
> From: Zhao1, Wei
> Sent: Thursday, November 1, 2018 4:29 PM
> To: Zhao1, Wei <wei.zhao1@intel.com>; dev@dpdk.org
> Cc: stable@dpdk.org; Zhang, Qi Z <qi.z.zhang@intel.com>;
> yamashita.hideyuki@po.ntt-tx.co.jp; stephen@networkplumber.org
> Subject: [PATCH v2] net/ixgbe: check jumbo frame enable parameter
> 
> There is necessary to do some check of max packet size boundary for code
> safe in order to avoid error in register setting when enable jumbo.
> 
> Signed-off-by: Wei Zhao <wei.zhao1@intel.com>
> 
> ---
> 
> v2:
> -add more log infomation and fix build issue
> ---
>  drivers/net/ixgbe/ixgbe_ethdev.c |  4 +---
> drivers/net/ixgbe/ixgbe_ethdev.h |  2 ++
>  drivers/net/ixgbe/ixgbe_rxtx.c   | 31
> +++++++++++++++++++++++++++++++
>  3 files changed, 34 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/net/ixgbe/ixgbe_ethdev.c
> b/drivers/net/ixgbe/ixgbe_ethdev.c
> index 5a2c351..d65a911 100644
> --- a/drivers/net/ixgbe/ixgbe_ethdev.c
> +++ b/drivers/net/ixgbe/ixgbe_ethdev.c
> @@ -173,8 +173,6 @@ static int
> ixgbe_dev_queue_stats_mapping_set(struct rte_eth_dev *eth_dev,
>  					     uint8_t is_rx);
>  static int ixgbe_fw_version_get(struct rte_eth_dev *dev, char *fw_version,
>  				 size_t fw_size);
> -static void ixgbe_dev_info_get(struct rte_eth_dev *dev,
> -			       struct rte_eth_dev_info *dev_info);
>  static const uint32_t *ixgbe_dev_supported_ptypes_get(struct
> rte_eth_dev *dev);  static void ixgbevf_dev_info_get(struct rte_eth_dev
> *dev,
>  				 struct rte_eth_dev_info *dev_info); @@ -
> 3692,7 +3690,7 @@ static int ixgbevf_dev_xstats_get_names(__rte_unused
> struct rte_eth_dev *dev,
>  		return 0;
>  }
> 
> -static void
> +void
>  ixgbe_dev_info_get(struct rte_eth_dev *dev, struct rte_eth_dev_info
> *dev_info)  {
>  	struct rte_pci_device *pci_dev = RTE_ETH_DEV_TO_PCI(dev); diff --
> git a/drivers/net/ixgbe/ixgbe_ethdev.h b/drivers/net/ixgbe/ixgbe_ethdev.h
> index d0b9396..a474be4 100644
> --- a/drivers/net/ixgbe/ixgbe_ethdev.h
> +++ b/drivers/net/ixgbe/ixgbe_ethdev.h
> @@ -727,6 +727,8 @@ int ixgbe_action_rss_same(const struct
> rte_flow_action_rss *comp,
>  			  const struct rte_flow_action_rss *with);  int
> ixgbe_config_rss_filter(struct rte_eth_dev *dev,
>  		struct ixgbe_rte_flow_rss_conf *conf, bool add);
> +void ixgbe_dev_info_get(struct rte_eth_dev *dev,
> +			       struct rte_eth_dev_info *dev_info);
> 
>  static inline int
>  ixgbe_ethertype_filter_lookup(struct ixgbe_filter_info *filter_info, diff --git
> a/drivers/net/ixgbe/ixgbe_rxtx.c b/drivers/net/ixgbe/ixgbe_rxtx.c index
> 2f0262a..94051ca 100644
> --- a/drivers/net/ixgbe/ixgbe_rxtx.c
> +++ b/drivers/net/ixgbe/ixgbe_rxtx.c
> @@ -4814,6 +4814,34 @@ void __attribute__((cold))
>  	return 0;
>  }
> 
> +static int __attribute__((cold))
> +ixgbe_dev_jumboenable_check(struct rte_eth_dev *dev,
> +				uint16_t max_rx_pkt_len)
> +{
> +	struct rte_eth_dev_info dev_info;
> +
> +	ixgbe_dev_info_get(dev, &dev_info);
> +
> +	/* check that max packet size is within the allowed range */
> +	if (max_rx_pkt_len < ETHER_MIN_MTU) {
> +		PMD_INIT_LOG(ERR, "max packet size is too small.");
> +		return -EINVAL;
> +	}
> +
> +	if (max_rx_pkt_len > dev_info.max_rx_pktlen) {
> +		PMD_INIT_LOG(ERR, "max packet size is too big.");
> +		return -EINVAL;
> +	}
> +
> +	/* check jumbo mode if needed */
> +	if (max_rx_pkt_len < ETHER_MAX_LEN) {
> +		PMD_INIT_LOG(ERR, "No need to enable jumbo.");
> +		return -EINVAL;
> +	}
> +
> +	return 0;
> +}
> +
>  /*
>   * Initializes Receive Unit.
>   */
> @@ -4865,6 +4893,9 @@ int __attribute__((cold))
>  	 * Configure jumbo frame support, if any.
>  	 */
>  	if (rx_conf->offloads & DEV_RX_OFFLOAD_JUMBO_FRAME) {
> +		if (ixgbe_dev_jumboenable_check(dev, rx_conf-
> >max_rx_pkt_len))
> +			return -EINVAL;
> +
>  		hlreg0 |= IXGBE_HLREG0_JUMBOEN;
>  		maxfrs = IXGBE_READ_REG(hw, IXGBE_MAXFRS);
>  		maxfrs &= 0x0000FFFF;
> --
> 1.8.3.1