bpf: xdp: Allow head adjustment in XDP prog
This patch allows XDP prog to extend/remove the packet
data at the head (like adding or removing header). It is
done by adding a new XDP helper bpf_xdp_adjust_head().
It also renames bpf_helper_changes_skb_data() to
bpf_helper_changes_pkt_data() to better reflect
that XDP prog does not work on skb.
This patch adds one "xdp_adjust_head" bit to bpf_prog for the
XDP-capable driver to check if the XDP prog requires
bpf_xdp_adjust_head() support. The driver can then decide
to error out during XDP_SETUP_PROG.
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/ethernet/mellanox/mlx4/en_netdev.c b/drivers/net/ethernet/mellanox/mlx4/en_netdev.c
index 49a81f1..f441eda 100644
--- a/drivers/net/ethernet/mellanox/mlx4/en_netdev.c
+++ b/drivers/net/ethernet/mellanox/mlx4/en_netdev.c
@@ -2686,6 +2686,11 @@ static int mlx4_xdp_set(struct net_device *dev, struct bpf_prog *prog)
int err;
int i;
+ if (prog && prog->xdp_adjust_head) {
+ en_err(priv, "Does not support bpf_xdp_adjust_head()\n");
+ return -EOPNOTSUPP;
+ }
+
xdp_ring_num = prog ? priv->rx_ring_num : 0;
/* No need to reconfigure buffers when simply swapping the
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
index 0702027..cbfa38f 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
@@ -3183,6 +3183,11 @@ static int mlx5e_xdp_set(struct net_device *netdev, struct bpf_prog *prog)
bool reset, was_opened;
int i;
+ if (prog && prog->xdp_adjust_head) {
+ netdev_err(netdev, "Does not support bpf_xdp_adjust_head()\n");
+ return -EOPNOTSUPP;
+ }
+
mutex_lock(&priv->state_lock);
if ((netdev->features & NETIF_F_LRO) && prog) {
diff --git a/drivers/net/ethernet/netronome/nfp/nfp_net_common.c b/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
index 00d9a03..e8d4481 100644
--- a/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
+++ b/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
@@ -2946,6 +2946,10 @@ static int nfp_net_xdp_setup(struct nfp_net *nn, struct bpf_prog *prog)
};
int err;
+ if (prog && prog->xdp_adjust_head) {
+ nn_err(nn, "Does not support bpf_xdp_adjust_head()\n");
+ return -EOPNOTSUPP;
+ }
if (!prog && !nn->xdp_prog)
return 0;
if (prog && nn->xdp_prog) {
diff --git a/drivers/net/ethernet/qlogic/qede/qede_main.c b/drivers/net/ethernet/qlogic/qede/qede_main.c
index cf1dd14..aecdd1c 100644
--- a/drivers/net/ethernet/qlogic/qede/qede_main.c
+++ b/drivers/net/ethernet/qlogic/qede/qede_main.c
@@ -2507,6 +2507,11 @@ static int qede_xdp_set(struct qede_dev *edev, struct bpf_prog *prog)
{
struct qede_reload_args args;
+ if (prog && prog->xdp_adjust_head) {
+ DP_ERR(edev, "Does not support bpf_xdp_adjust_head()\n");
+ return -EOPNOTSUPP;
+ }
+
/* If we're called, there was already a bpf reference increment */
args.func = &qede_xdp_reload_func;
args.u.new_prog = prog;