From: Martin KaFai Lau <kafai@fb.com>
Date: Thu, 15 Jun 2017 17:29:10 -0700
Subject: bpf: mlx4: Report bpf_prog ID during XDP_QUERY_PROG
Patch-mainline: v4.13-rc1
Git-commit: 2e37e9b0f55e50a099c699ac41ea4fa507fc46ff
References: bsc#1046299 FATE#322947

Add support to mlx4 to report bpf_prog ID during XDP_QUERY_PROG.

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Cc: Tariq Toukan <tariqt@mellanox.com>
Cc: Saeed Mahameed <saeedm@mellanox.com>
Acked-by: Alexei Starovoitov <ast@fb.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 drivers/net/ethernet/mellanox/mlx4/en_netdev.c |   21 ++++++++++++++++++---
 1 file changed, 18 insertions(+), 3 deletions(-)

--- a/drivers/net/ethernet/mellanox/mlx4/en_netdev.c
+++ b/drivers/net/ethernet/mellanox/mlx4/en_netdev.c
@@ -2825,11 +2825,25 @@ out:
 	return err;
 }
 
-static bool mlx4_xdp_attached(struct net_device *dev)
+static u32 mlx4_xdp_query(struct net_device *dev)
 {
 	struct mlx4_en_priv *priv = netdev_priv(dev);
+	struct mlx4_en_dev *mdev = priv->mdev;
+	const struct bpf_prog *xdp_prog;
+	u32 prog_id = 0;
 
-	return !!priv->tx_ring_num[TX_XDP];
+	if (!priv->tx_ring_num[TX_XDP])
+		return prog_id;
+
+	mutex_lock(&mdev->state_lock);
+	xdp_prog = rcu_dereference_protected(
+		priv->rx_ring[0]->xdp_prog,
+		lockdep_is_held(&mdev->state_lock));
+	if (xdp_prog)
+		prog_id = xdp_prog->aux->id;
+	mutex_unlock(&mdev->state_lock);
+
+	return prog_id;
 }
 
 static int mlx4_xdp(struct net_device *dev, struct netdev_xdp *xdp)
@@ -2838,7 +2852,8 @@ static int mlx4_xdp(struct net_device *d
 	case XDP_SETUP_PROG:
 		return mlx4_xdp_set(dev, xdp->prog);
 	case XDP_QUERY_PROG:
-		xdp->prog_attached = mlx4_xdp_attached(dev);
+		xdp->prog_id = mlx4_xdp_query(dev);
+		xdp->prog_attached = !!xdp->prog_id;
 		return 0;
 	default:
 		return -EINVAL;