Subject: Re: [PATCH 1/1] tun: change speed from 10M to dynamically configured

From: yzhu1 <[email-masked]>
Date: Fri, 13 Feb 2015 18:03:10 +0800

add [email-masked], the maintainer of tun/tap driver.

Zhu Yanjun
On 02/13/2015 02:19 PM, Zhu Yanjun wrote:
> The default speed of normal nic is 1000M while the default speed
> of tun is 10M. Now the default speed of tun is changed to 1000M.
> And there are 3 options: 10M, 100M and 1000M to the speed of tun.
> The command "ethtool -s tun0 speed 10/100/1000" can configure the
> speed of tun dynamically.
>
> CC: Michael S. Tsirkin <[email-masked]>
> CC: Jason Wang <[email-masked]>
> CC: Al Viro <[email-masked]>
> Reviewed-by: Sergei Shtylyov <[email-masked]>
> Reviewed-by: Jonathon Reinhart <[email-masked]>
> Signed-off-by: Zhu Yanjun <[email-masked]>
> ---
>   drivers/net/tun.c           | 43 ++++++++++++++++++++++++++++++++++++++++++-
>   include/uapi/linux/if_tun.h |  5 +++++
>   2 files changed, 47 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/net/tun.c b/drivers/net/tun.c
> index 8c8dc16..423b276 100644
> --- a/drivers/net/tun.c
> +++ b/drivers/net/tun.c
> @@ -950,6 +950,9 @@ static void tun_net_init(struct net_device *dev)
>   		dev->addr_len = 0;
>   		dev->mtu = 1500;
>   
> +		/* Set default speed 1000M */
> +		tun->flags |= TUN_CTRL_SPD_1000;
> +
>   		/* Zero header length */
>   		dev->type = ARPHRD_NONE;
>   		dev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST;
> @@ -2257,9 +2260,18 @@ static struct miscdevice tun_miscdev = {
>   
>   static int tun_get_settings(struct net_device *dev, struct ethtool_cmd *cmd)
>   {
> +	struct tun_struct *tun = netdev_priv(dev);
> +
> +	/* Get the speed of tun */
> +	if (tun->flags & TUN_CTRL_SPD_1000) {
> +		ethtool_cmd_speed_set(cmd, SPEED_1000);
> +	} else if (tun->flags & TUN_CTRL_SPD_100) {
> +		ethtool_cmd_speed_set(cmd, SPEED_100);
> +	} else
> +		ethtool_cmd_speed_set(cmd, SPEED_10);
> +
>   	cmd->supported		= 0;
>   	cmd->advertising	= 0;
> -	ethtool_cmd_speed_set(cmd, SPEED_10);
>   	cmd->duplex		= DUPLEX_FULL;
>   	cmd->port		= PORT_TP;
>   	cmd->phy_address	= 0;
> @@ -2287,6 +2299,34 @@ static void tun_get_drvinfo(struct net_device *dev, struct ethtool_drvinfo *info
>   	}
>   }
>   
> +static int tun_set_settings(struct net_device *dev, struct ethtool_cmd *cmd)
> +{
> +	struct tun_struct *tun = netdev_priv(dev);
> +	u32 speed = ethtool_cmd_speed(cmd);
> +	int ret = 0;
> +
> +	/* Set speed flag */
> +	switch (speed) {
> +	case 10:
> +		tun->flags &= ~(TUN_CTRL_SPD_100 | TUN_CTRL_SPD_1000);
> +		tun->flags |= TUN_CTRL_SPD_10;
> +		break;
> +	case 100:
> +		tun->flags &= ~(TUN_CTRL_SPD_10 | TUN_CTRL_SPD_1000);
> +		tun->flags |= TUN_CTRL_SPD_100;
> +		break;
> +	case 1000:
> +		tun->flags &= ~(TUN_CTRL_SPD_10 | TUN_CTRL_SPD_100);
> +		tun->flags |= TUN_CTRL_SPD_1000;
> +		break;
> +	default:
> +		ret = -EINVAL;
> +		tun_debug(KERN_INFO, tun, "wrong speed!\n");
> +	}
> +
> +	return ret;
> +}
> +
>   static u32 tun_get_msglevel(struct net_device *dev)
>   {
>   #ifdef TUN_DEBUG
> @@ -2307,6 +2347,7 @@ static void tun_set_msglevel(struct net_device *dev, u32 value)
>   
>   static const struct ethtool_ops tun_ethtool_ops = {
>   	.get_settings	= tun_get_settings,
> +	.set_settings	= tun_set_settings,
>   	.get_drvinfo	= tun_get_drvinfo,
>   	.get_msglevel	= tun_get_msglevel,
>   	.set_msglevel	= tun_set_msglevel,
> diff --git a/include/uapi/linux/if_tun.h b/include/uapi/linux/if_tun.h
> index 50ae243..78a09a7 100644
> --- a/include/uapi/linux/if_tun.h
> +++ b/include/uapi/linux/if_tun.h
> @@ -66,6 +66,11 @@
>   #define IFF_PERSIST	0x0800
>   #define IFF_NOFILTER	0x1000
>   
> +/*add speed control, default 1000M*/
> +#define TUN_CTRL_SPD_10         0x0020
> +#define TUN_CTRL_SPD_100        0x0040
> +#define TUN_CTRL_SPD_1000       0x0080
> +
>   /* Socket options */
>   #define TUN_TX_TIMESTAMP 1
>