Jason Wang
2022-Feb-09 04:25 UTC
[RFC PATCH 1/5] uapi/linux/if_tun.h: Added new ioctl for tun/tap.
? 2022/1/25 ??4:46, Andrew Melnychenko ??:> Added TUNGETSUPPORTEDOFFLOADS that should allow > to get bits of supported offloads.So we don't use dedicated ioctls in the past, instead, we just probing by checking the return value of TUNSETOFFLOADS. E.g qemu has the following codes: int tap_probe_has_ufo(int fd) { ??? unsigned offload; ??? offload = TUN_F_CSUM | TUN_F_UFO; ??? if (ioctl(fd, TUNSETOFFLOAD, offload) < 0) ??????? return 0; ??? return 1; } Any reason we can't keep using that? Thanks> Added 2 additional offlloads for USO(IPv4 & IPv6). > Separate offloads are required for Windows VM guests, > g.e. Windows may set USO rx only for IPv4. > > Signed-off-by: Andrew Melnychenko <andrew at daynix.com> > --- > include/uapi/linux/if_tun.h | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/include/uapi/linux/if_tun.h b/include/uapi/linux/if_tun.h > index 454ae31b93c7..07680fae6e18 100644 > --- a/include/uapi/linux/if_tun.h > +++ b/include/uapi/linux/if_tun.h > @@ -61,6 +61,7 @@ > #define TUNSETFILTEREBPF _IOR('T', 225, int) > #define TUNSETCARRIER _IOW('T', 226, int) > #define TUNGETDEVNETNS _IO('T', 227) > +#define TUNGETSUPPORTEDOFFLOADS _IOR('T', 228, unsigned int) > > /* TUNSETIFF ifr flags */ > #define IFF_TUN 0x0001 > @@ -88,6 +89,8 @@ > #define TUN_F_TSO6 0x04 /* I can handle TSO for IPv6 packets */ > #define TUN_F_TSO_ECN 0x08 /* I can handle TSO with ECN bits. */ > #define TUN_F_UFO 0x10 /* I can handle UFO packets */ > +#define TUN_F_USO4 0x20 /* I can handle USO for IPv4 packets */ > +#define TUN_F_USO6 0x40 /* I can handle USO for IPv6 packets */ > > /* Protocol info prepended to the packets (when IFF_NO_PI is not set) */ > #define TUN_PKT_STRIP 0x0001
Andrew Melnichenko
2022-Feb-22 13:28 UTC
[RFC PATCH 1/5] uapi/linux/if_tun.h: Added new ioctl for tun/tap.
Hi all, On Wed, Feb 9, 2022 at 6:26 AM Jason Wang <jasowang at redhat.com> wrote:> > > ? 2022/1/25 ??4:46, Andrew Melnychenko ??: > > Added TUNGETSUPPORTEDOFFLOADS that should allow > > to get bits of supported offloads. > > > So we don't use dedicated ioctls in the past, instead, we just probing > by checking the return value of TUNSETOFFLOADS. > > E.g qemu has the following codes: > > int tap_probe_has_ufo(int fd) > { > unsigned offload; > > offload = TUN_F_CSUM | TUN_F_UFO; > > if (ioctl(fd, TUNSETOFFLOAD, offload) < 0) > return 0; > > return 1; > } > > Any reason we can't keep using that? > > Thanks >Well, even in this example. To check the ufo feature, we trying to set it. What if we don't need to "enable" UFO and/or do not change its state? I think it's a good idea to have the ability to get supported offloads without changing device behavior.> > > Added 2 additional offlloads for USO(IPv4 & IPv6). > > Separate offloads are required for Windows VM guests, > > g.e. Windows may set USO rx only for IPv4. > > > > Signed-off-by: Andrew Melnychenko <andrew at daynix.com> > > --- > > include/uapi/linux/if_tun.h | 3 +++ > > 1 file changed, 3 insertions(+) > > > > diff --git a/include/uapi/linux/if_tun.h b/include/uapi/linux/if_tun.h > > index 454ae31b93c7..07680fae6e18 100644 > > --- a/include/uapi/linux/if_tun.h > > +++ b/include/uapi/linux/if_tun.h > > @@ -61,6 +61,7 @@ > > #define TUNSETFILTEREBPF _IOR('T', 225, int) > > #define TUNSETCARRIER _IOW('T', 226, int) > > #define TUNGETDEVNETNS _IO('T', 227) > > +#define TUNGETSUPPORTEDOFFLOADS _IOR('T', 228, unsigned int) > > > > /* TUNSETIFF ifr flags */ > > #define IFF_TUN 0x0001 > > @@ -88,6 +89,8 @@ > > #define TUN_F_TSO6 0x04 /* I can handle TSO for IPv6 packets */ > > #define TUN_F_TSO_ECN 0x08 /* I can handle TSO with ECN bits. */ > > #define TUN_F_UFO 0x10 /* I can handle UFO packets */ > > +#define TUN_F_USO4 0x20 /* I can handle USO for IPv4 packets */ > > +#define TUN_F_USO6 0x40 /* I can handle USO for IPv6 packets */ > > > > /* Protocol info prepended to the packets (when IFF_NO_PI is not set) */ > > #define TUN_PKT_STRIP 0x0001 >