xdp: support simultaneous driver and hw XDP attachment

Split the query of HW-attached program from the software one.
Introduce new .ndo_bpf command to query HW-attached program.
This will allow drivers to install different programs in HW
and SW at the same time.  Netlink can now also carry multiple
programs on dump (in which case mode will be set to
XDP_ATTACHED_MULTI and user has to check per-attachment point
attributes, IFLA_XDP_PROG_ID will not be present).  We reuse
IFLA_XDP_PROG_ID skb space for second mode, so rtnl_xdp_size()
doesn't need to be updated.

Note that the installation side is still not there, since all
drivers currently reject installing more than one program at
the time.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

1 files changed, 6 insertions, 0 deletions

diff --git a/drivers/net/netdevsim/bpf.c b/drivers/net/netdevsim/bpf.c
index c485d97b5df4..5544c9b51173 100644
--- a/drivers/net/netdevsim/bpf.c
+++ b/drivers/net/netdevsim/bpf.c
@@ -561,6 +561,12 @@ int nsim_bpf(struct net_device *dev, struct netdev_bpf *bpf)
                 nsim_bpf_destroy_prog(bpf->offload.prog);
                 return 0;
         case XDP_QUERY_PROG:
+                if (ns->xdp_prog_mode != XDP_ATTACHED_DRV)
+                        return 0;
+                return xdp_attachment_query(&ns->xdp, bpf);
+        case XDP_QUERY_PROG_HW:
+                if (ns->xdp_prog_mode != XDP_ATTACHED_HW)
+                        return 0;
                 return xdp_attachment_query(&ns->xdp, bpf);
         case XDP_SETUP_PROG:
                 err = nsim_setup_prog_checks(ns, bpf);