nfp: bpf: use extack support to improve debugging

Use the recently added extack support for eBPF offload in the driver.
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>

drivers/net/ethernet/netronome/nfp/bpf/main.c

@@ -70,7 +70,7 @@ nfp_bpf_xdp_offload(struct nfp_app *app, struct nfp_net *nn,
 	if (prog && running && !xdp_running)
 		return -EBUSY;
 
-	ret = nfp_net_bpf_offload(nn, prog, running);
+	ret = nfp_net_bpf_offload(nn, prog, running, extack);
 	/* Stop offload if replace not possible */
 	if (ret && prog)
 		nfp_bpf_xdp_offload(app, nn, NULL, extack);
@@ -125,17 +125,31 @@ static int nfp_bpf_setup_tc_block_cb(enum tc_setup_type type,
 	struct nfp_bpf_vnic *bv;
 	int err;
 
-	if (type != TC_SETUP_CLSBPF ||
-	    !tc_can_offload(nn->dp.netdev) ||
-	    !nfp_net_ebpf_capable(nn) ||
-	    cls_bpf->common.protocol != htons(ETH_P_ALL) ||
-	    cls_bpf->common.chain_index)
+	if (type != TC_SETUP_CLSBPF) {
+		NL_SET_ERR_MSG_MOD(cls_bpf->common.extack,
+				   "only offload of BPF classifiers supported");
+		return -EOPNOTSUPP;
+	}
+	if (!tc_can_offload_extack(nn->dp.netdev, cls_bpf->common.extack))
+		return -EOPNOTSUPP;
+	if (!nfp_net_ebpf_capable(nn)) {
+		NL_SET_ERR_MSG_MOD(cls_bpf->common.extack,
+				   "NFP firmware does not support eBPF offload");
+		return -EOPNOTSUPP;
+	}
+	if (cls_bpf->common.protocol != htons(ETH_P_ALL)) {
+		NL_SET_ERR_MSG_MOD(cls_bpf->common.extack,
+				   "only ETH_P_ALL supported as filter protocol");
+		return -EOPNOTSUPP;
+	}
+	if (cls_bpf->common.chain_index)
 		return -EOPNOTSUPP;
 
 	/* Only support TC direct action */
 	if (!cls_bpf->exts_integrated ||
 	    tcf_exts_has_actions(cls_bpf->exts)) {
-		nn_err(nn, "only direct action with no legacy actions supported\n");
+		NL_SET_ERR_MSG_MOD(cls_bpf->common.extack,
+				   "only direct action with no legacy actions supported");
 		return -EOPNOTSUPP;
 	}
 
@@ -152,7 +166,8 @@ static int nfp_bpf_setup_tc_block_cb(enum tc_setup_type type,
 			return 0;
 	}
 
-	err = nfp_net_bpf_offload(nn, cls_bpf->prog, oldprog);
+	err = nfp_net_bpf_offload(nn, cls_bpf->prog, oldprog,
+				  cls_bpf->common.extack);
 	if (err)
 		return err;
 

drivers/net/ethernet/netronome/nfp/bpf/main.h

@@ -335,7 +335,7 @@ struct nfp_net;
 int nfp_ndo_bpf(struct nfp_app *app, struct nfp_net *nn,
 		struct netdev_bpf *bpf);
 int nfp_net_bpf_offload(struct nfp_net *nn, struct bpf_prog *prog,
-			bool old_prog);
+			bool old_prog, struct netlink_ext_ack *extack);
 
 struct nfp_insn_meta *
 nfp_bpf_goto_meta(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta,

drivers/net/ethernet/netronome/nfp/bpf/offload.c

@@ -281,7 +281,9 @@ int nfp_ndo_bpf(struct nfp_app *app, struct nfp_net *nn, struct netdev_bpf *bpf)
 	}
 }
 
-static int nfp_net_bpf_load(struct nfp_net *nn, struct bpf_prog *prog)
+static int
+nfp_net_bpf_load(struct nfp_net *nn, struct bpf_prog *prog,
+		 struct netlink_ext_ack *extack)
 {
 	struct nfp_prog *nfp_prog = prog->aux->offload->dev_priv;
 	unsigned int max_mtu;
@@ -291,7 +293,7 @@ static int nfp_net_bpf_load(struct nfp_net *nn, struct bpf_prog *prog)
 
 	max_mtu = nn_readb(nn, NFP_NET_CFG_BPF_INL_MTU) * 64 - 32;
 	if (max_mtu < nn->dp.netdev->mtu) {
-		nn_info(nn, "BPF offload not supported with MTU larger than HW packet split boundary\n");
+		NL_SET_ERR_MSG_MOD(extack, "BPF offload not supported with MTU larger than HW packet split boundary");
 		return -EOPNOTSUPP;
 	}
 
@@ -313,7 +315,8 @@ static int nfp_net_bpf_load(struct nfp_net *nn, struct bpf_prog *prog)
 	/* Load up the JITed code */
 	err = nfp_net_reconfig(nn, NFP_NET_CFG_UPDATE_BPF);
 	if (err)
-		nn_err(nn, "FW command error while loading BPF: %d\n", err);
+		NL_SET_ERR_MSG_MOD(extack,
+				   "FW command error while loading BPF");
 
 	dma_unmap_single(nn->dp.dev, dma_addr, nfp_prog->prog_len * sizeof(u64),
 			 DMA_TO_DEVICE);
@@ -322,7 +325,8 @@ static int nfp_net_bpf_load(struct nfp_net *nn, struct bpf_prog *prog)
 	return err;
 }
 
-static void nfp_net_bpf_start(struct nfp_net *nn)
+static void
+nfp_net_bpf_start(struct nfp_net *nn, struct netlink_ext_ack *extack)
 {
 	int err;
 
@@ -331,7 +335,8 @@ static void nfp_net_bpf_start(struct nfp_net *nn)
 	nn_writel(nn, NFP_NET_CFG_CTRL, nn->dp.ctrl);
 	err = nfp_net_reconfig(nn, NFP_NET_CFG_UPDATE_GEN);
 	if (err)
-		nn_err(nn, "FW command error while enabling BPF: %d\n", err);
+		NL_SET_ERR_MSG_MOD(extack,
+				   "FW command error while enabling BPF");
 }
 
 static int nfp_net_bpf_stop(struct nfp_net *nn)
@@ -346,7 +351,7 @@ static int nfp_net_bpf_stop(struct nfp_net *nn)
 }
 
 int nfp_net_bpf_offload(struct nfp_net *nn, struct bpf_prog *prog,
-			bool old_prog)
+			bool old_prog, struct netlink_ext_ack *extack)
 {
 	int err;
 
@@ -364,7 +369,8 @@ int nfp_net_bpf_offload(struct nfp_net *nn, struct bpf_prog *prog,
 
 		cap = nn_readb(nn, NFP_NET_CFG_BPF_CAP);
 		if (!(cap & NFP_NET_BPF_CAP_RELO)) {
-			nn_err(nn, "FW does not support live reload\n");
+			NL_SET_ERR_MSG_MOD(extack,
+					   "FW does not support live reload");
 			return -EBUSY;
 		}
 	}
@@ -376,12 +382,12 @@ int nfp_net_bpf_offload(struct nfp_net *nn, struct bpf_prog *prog,
 	if (old_prog && !prog)
 		return nfp_net_bpf_stop(nn);
 
-	err = nfp_net_bpf_load(nn, prog);
+	err = nfp_net_bpf_load(nn, prog, extack);
 	if (err)
 		return err;
 
 	if (!old_prog)
-		nfp_net_bpf_start(nn);
+		nfp_net_bpf_start(nn, extack);
 
 	return 0;
 }