On Fri, Dec 04, 2020 at 01:18:31PM +0100, Toke Høiland-Jørgensen wrote: > alardam@xxxxxxxxx writes: > > > From: Marek Majtyka <marekx.majtyka@xxxxxxxxx> > > > > Implement support for checking what kind of xdp functionality a netdev > > supports. Previously, there was no way to do this other than to try > > to create an AF_XDP socket on the interface or load an XDP program and see > > if it worked. This commit changes this by adding a new variable which > > describes all xdp supported functions on pretty detailed level: > > I like the direction this is going! :) > > > - aborted > > - drop > > - pass > > - tx > > - redirect > > Drivers can in principle implement support for the XDP_REDIRECT return > code (and calling xdp_do_redirect()) without implementing ndo_xdp_xmit() > for being the *target* of a redirect. While my quick grepping doesn't > turn up any drivers that do only one of these right now, I think we've > had examples of it in the past, so it would probably be better to split > the redirect feature flag in two. > > This would also make it trivial to replace the check in __xdp_enqueue() > (in devmap.c) from looking at whether the ndo is defined, and just > checking the flag. It would be great if you could do this as part of > this series. > > Maybe we could even make the 'redirect target' flag be set automatically > if a driver implements ndo_xdp_xmit? +1 > > > - zero copy > > - hardware offload. > > > > Zerocopy mode requires that redirect xdp operation is implemented > > in a driver and the driver supports also zero copy mode. > > Full mode requires that all xdp operation are implemented in the driver. > > Basic mode is just full mode without redirect operation. > > > > Initially, these new flags are disabled for all drivers by default. > > > > Signed-off-by: Marek Majtyka <marekx.majtyka@xxxxxxxxx> > > --- > > .../networking/netdev-xdp-properties.rst | 42 ++++++++ > > include/linux/netdevice.h | 2 + > > include/linux/xdp_properties.h | 53 +++++++++++ > > include/net/xdp.h | 95 +++++++++++++++++++ > > include/net/xdp_sock_drv.h | 10 ++ > > include/uapi/linux/ethtool.h | 1 + > > include/uapi/linux/xdp_properties.h | 32 +++++++ > > net/ethtool/common.c | 11 +++ > > net/ethtool/common.h | 4 + > > net/ethtool/strset.c | 5 + > > 10 files changed, 255 insertions(+) > > create mode 100644 Documentation/networking/netdev-xdp-properties.rst > > create mode 100644 include/linux/xdp_properties.h > > create mode 100644 include/uapi/linux/xdp_properties.h > > > > diff --git a/Documentation/networking/netdev-xdp-properties.rst b/Documentation/networking/netdev-xdp-properties.rst > > new file mode 100644 > > index 000000000000..4a434a1c512b > > --- /dev/null > > +++ b/Documentation/networking/netdev-xdp-properties.rst > > @@ -0,0 +1,42 @@ > > +.. SPDX-License-Identifier: GPL-2.0 > > + > > +===================== > > +Netdev XDP properties > > +===================== > > + > > + * XDP PROPERTIES FLAGS > > + > > +Following netdev xdp properties flags can be retrieve over netlink ethtool > > +interface the same way as netdev feature flags. These properties flags are > > +read only and cannot be change in the runtime. > > + > > + > > +* XDP_ABORTED > > + > > +This property informs if netdev supports xdp aborted action. > > + > > +* XDP_DROP > > + > > +This property informs if netdev supports xdp drop action. > > + > > +* XDP_PASS > > + > > +This property informs if netdev supports xdp pass action. > > + > > +* XDP_TX > > + > > +This property informs if netdev supports xdp tx action. > > + > > +* XDP_REDIRECT > > + > > +This property informs if netdev supports xdp redirect action. > > +It assumes the all beforehand mentioned flags are enabled. > > + > > +* XDP_ZEROCOPY > > + > > +This property informs if netdev driver supports xdp zero copy. > > +It assumes the all beforehand mentioned flags are enabled. > > Nit: I think 'XDP_ZEROCOPY' can lead people to think that this is > zero-copy support for all XDP operations, which is obviously not the > case. So maybe 'XDP_SOCK_ZEROCOPY' (and update the description to > mention AF_XDP sockets explicitly)? AF_XDP_ZEROCOPY? > > -Toke >
