On Tue, Oct 31, 2017 at 7:32 PM, Jason Wang <jasow...@redhat.com> wrote:
> This patch introduces new ioctl for change packet steering policy for
> tun. Only automatic flow steering is supported, more policies will
> come.
>
> Signed-off-by: Jason Wang <jasow...@redhat.com>
> ---
> drivers/net/tun.c | 35 ++++++++++++++++++++++++++++++++++-
> include/uapi/linux/if_tun.h | 7 +++++++
> 2 files changed, 41 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/net/tun.c b/drivers/net/tun.c
> index bff6259..ab109ff 100644
> --- a/drivers/net/tun.c
> +++ b/drivers/net/tun.c
> @@ -122,7 +122,8 @@ do {
> \
> #define TUN_VNET_BE 0x40000000
>
> #define TUN_FEATURES (IFF_NO_PI | IFF_ONE_QUEUE | IFF_VNET_HDR | \
> - IFF_MULTI_QUEUE | IFF_NAPI | IFF_NAPI_FRAGS)
> + IFF_MULTI_QUEUE | IFF_NAPI | IFF_NAPI_FRAGS | \
> + IFF_MULTI_STEERING)
>
> #define GOODCOPY_LEN 128
>
> @@ -2516,6 +2517,7 @@ static long __tun_chr_ioctl(struct file *file, unsigned
> int cmd,
> unsigned int ifindex;
> int le;
> int ret;
> + unsigned int steering;
>
> if (cmd == TUNSETIFF || cmd == TUNSETQUEUE || _IOC_TYPE(cmd) ==
> SOCK_IOC_TYPE) {
> if (copy_from_user(&ifr, argp, ifreq_len))
> @@ -2774,6 +2776,37 @@ static long __tun_chr_ioctl(struct file *file,
> unsigned int cmd,
> ret = 0;
> break;
>
> + case TUNSETSTEERING:
> + ret = -EFAULT;
> + if (copy_from_user(&steering, argp, sizeof(steering)))
> + break;
> + ret = 0;
> + switch (steering) {
> + case TUN_STEERING_AUTOMQ:
> + tun->steering_ops = &tun_automq_ops;
> + break;
> + default:
> + ret = -EFAULT;
> + }
> + break;
> +
> + case TUNGETSTEERING:
> + ret = 0;
> + if (tun->steering_ops == &tun_automq_ops)
> + steering = TUN_STEERING_AUTOMQ;
> + else
> + BUG();
> + if (copy_to_user(argp, &steering, sizeof(steering)))
> + ret = -EFAULT;
> + break;
> +
> + case TUNGETSTEERINGFEATURES:
> + ret = 0;
> + steering = TUN_STEERING_AUTOMQ;
> + if (copy_to_user(argp, &steering, sizeof(steering)))
> + ret = -EFAULT;
> + break;
> +
Similar to my comment in patch 1/3: if only eBPF is used, these
calls can be avoided in favor of only TUNSETSTEERINGEBPF
from patch 3/3.
