From: Quentin Monnet <quentin.monnet@netronome.com>
Date: Tue, 23 Jan 2018 11:22:52 -0800
Subject: netdevsim: add extack support for TC eBPF offload
Patch-mainline: v4.16-rc1
Git-commit: 728461f202c316798e3300674006dce18cfdfcea
References: bsc#1109837

Use the recently added extack support for TC eBPF filters in netdevsim.

Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 drivers/net/netdevsim/bpf.c |   36 +++++++++++++++++++++++++++---------
 1 file changed, 27 insertions(+), 9 deletions(-)

--- a/drivers/net/netdevsim/bpf.c
+++ b/drivers/net/netdevsim/bpf.c
@@ -123,20 +123,35 @@ int nsim_bpf_setup_tc_block_cb(enum tc_s
 	struct netdevsim *ns = cb_priv;
 	struct bpf_prog *oldprog;
 
-	if (type != TC_SETUP_CLSBPF ||
-	    !tc_can_offload(ns->netdev) ||
-	    cls_bpf->common.protocol != htons(ETH_P_ALL) ||
-	    cls_bpf->common.chain_index)
+	if (type != TC_SETUP_CLSBPF) {
+		NSIM_EA(cls_bpf->common.extack,
+			"only offload of BPF classifiers supported");
+		return -EOPNOTSUPP;
+	}
+
+	if (!tc_can_offload_extack(ns->netdev, cls_bpf->common.extack))
 		return -EOPNOTSUPP;
 
-	if (nsim_xdp_offload_active(ns))
-		return -EBUSY;
+	if (cls_bpf->common.protocol != htons(ETH_P_ALL)) {
+		NSIM_EA(cls_bpf->common.extack,
+			"only ETH_P_ALL supported as filter protocol");
+		return -EOPNOTSUPP;
+	}
 
-	if (!ns->bpf_tc_accept)
+	if (cls_bpf->common.chain_index)
 		return -EOPNOTSUPP;
+
+	if (!ns->bpf_tc_accept) {
+		NSIM_EA(cls_bpf->common.extack,
+			"netdevsim configured to reject BPF TC offload");
+		return -EOPNOTSUPP;
+	}
 	/* Note: progs without skip_sw will probably not be dev bound */
-	if (prog && !prog->aux->offload && !ns->bpf_tc_non_bound_accept)
+	if (prog && !prog->aux->offload && !ns->bpf_tc_non_bound_accept) {
+		NSIM_EA(cls_bpf->common.extack,
+			"netdevsim configured to reject unbound programs");
 		return -EOPNOTSUPP;
+	}
 
 	if (cls_bpf->command != TC_CLSBPF_OFFLOAD)
 		return -EOPNOTSUPP;
@@ -148,8 +163,11 @@ int nsim_bpf_setup_tc_block_cb(enum tc_s
 		oldprog = NULL;
 		if (!cls_bpf->prog)
 			return 0;
-		if (ns->bpf_offloaded)
+		if (ns->bpf_offloaded) {
+			NSIM_EA(cls_bpf->common.extack,
+				"driver and netdev offload states mismatch");
 			return -EBUSY;
+		}
 	}
 
 	return nsim_bpf_offload(ns, cls_bpf->prog, oldprog);