net: xdp: allow generic and driver XDP on one interface

Since commit a25717d2b604 ("xdp: support simultaneous driver and
hw XDP attachment") users can load an XDP program for offload and
in native driver mode simultaneously.  Allow a similar mix of
offload and SKB mode/generic XDP.

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>

diff --git a/net/core/dev.c b/net/core/dev.c
index bfa4be42afff7e2cb2340d098873765e61ef67a5..78c3b48392e1d8bad38a99578fa492e724846df0 100644 (file)
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -7976,11 +7976,13 @@ int dev_change_xdp_fd(struct net_device *dev, struct netlink_ext_ack *extack,
        enum bpf_netdev_command query;
        struct bpf_prog *prog = NULL;
        bpf_op_t bpf_op, bpf_chk;
+       bool offload;
        int err;
 
        ASSERT_RTNL();
 
-       query = flags & XDP_FLAGS_HW_MODE ? XDP_QUERY_PROG_HW : XDP_QUERY_PROG;
+       offload = flags & XDP_FLAGS_HW_MODE;
+       query = offload ? XDP_QUERY_PROG_HW : XDP_QUERY_PROG;
 
        bpf_op = bpf_chk = ops->ndo_bpf;
        if (!bpf_op && (flags & (XDP_FLAGS_DRV_MODE | XDP_FLAGS_HW_MODE))) {
@@ -7993,8 +7995,7 @@ int dev_change_xdp_fd(struct net_device *dev, struct netlink_ext_ack *extack,
                bpf_chk = generic_xdp_install;
 
        if (fd >= 0) {
-               if (__dev_xdp_query(dev, bpf_chk, XDP_QUERY_PROG) ||
-                   __dev_xdp_query(dev, bpf_chk, XDP_QUERY_PROG_HW)) {
+               if (!offload && __dev_xdp_query(dev, bpf_chk, XDP_QUERY_PROG)) {
                        NL_SET_ERR_MSG(extack, "native and generic XDP can't be active at the same time");
                        return -EEXIST;
                }
@@ -8009,8 +8010,7 @@ int dev_change_xdp_fd(struct net_device *dev, struct netlink_ext_ack *extack,
                if (IS_ERR(prog))
                        return PTR_ERR(prog);
 
-               if (!(flags & XDP_FLAGS_HW_MODE) &&
-                   bpf_prog_is_dev_bound(prog->aux)) {
+               if (!offload && bpf_prog_is_dev_bound(prog->aux)) {
                        NL_SET_ERR_MSG(extack, "using device-bound program without HW_MODE flag is not supported");
                        bpf_prog_put(prog);
                        return -EINVAL;