Merge branch 'lan966x-xdp'

Horatiu Vultur says:

====================
net: lan966x: Add xdp support

Add support for xdp in lan966x driver. Currently only XDP_PASS and
XDP_DROP are supported.

The first 2 patches are just moving things around just to simplify
the code for when the xdp is added.
Patch 3 actually adds the xdp. Currently the only supported actions
are XDP_PASS and XDP_DROP. In the future this will be extended with
XDP_TX and XDP_REDIRECT.
Patch 4 changes to use page pool API, because the handling of the
pages is similar with what already lan966x driver is doing. In this
way is possible to remove some of the code.

All these changes give a small improvement on the RX side:
Before:
iperf3 -c 10.96.10.1 -R
[  5]   0.00-10.01  sec   514 MBytes   430 Mbits/sec    0         sender
[  5]   0.00-10.00  sec   509 MBytes   427 Mbits/sec              receiver

After:
iperf3 -c 10.96.10.1 -R
[  5]   0.00-10.02  sec   540 MBytes   452 Mbits/sec    0         sender
[  5]   0.00-10.01  sec   537 MBytes   450 Mbits/sec              receiver

---
v2->v3:
- inline lan966x_xdp_port_present
- update max_len of page_pool_params not to be the page size anymore but
  actually be rx->max_mtu.

v1->v2:
- rebase on net-next, once the fixes for FDMA and MTU were accepted
- drop patch 2, which changes the MTU as is not needed anymore
- allow to run xdp programs on frames bigger than 4KB
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/microchip/lan966x/Kconfig

@@ -7,5 +7,6 @@ config LAN966X_SWITCH
 	depends on BRIDGE || BRIDGE=n
 	select PHYLINK
 	select PACKING
+	select PAGE_POOL
 	help
 	  This driver supports the Lan966x network switch device.

drivers/net/ethernet/microchip/lan966x/Makefile

@@ -11,4 +11,5 @@ lan966x-switch-objs  := lan966x_main.o lan966x_phylink.o lan966x_port.o \
 			lan966x_ptp.o lan966x_fdma.o lan966x_lag.o \
 			lan966x_tc.o lan966x_mqprio.o lan966x_taprio.o \
 			lan966x_tbf.o lan966x_cbs.o lan966x_ets.o \
-			lan966x_tc_matchall.o lan966x_police.o lan966x_mirror.o
+			lan966x_tc_matchall.o lan966x_police.o lan966x_mirror.o \
+			lan966x_xdp.o

drivers/net/ethernet/microchip/lan966x/lan966x_ifh.h

@@ -8,6 +8,7 @@
  */
 
 #define IFH_LEN                      7
+#define IFH_LEN_BYTES                (IFH_LEN * sizeof(u32))
 
 /* Timestamp for frame */
 #define IFH_POS_TIMESTAMP            192

drivers/net/ethernet/microchip/lan966x/lan966x_main.c

@@ -468,6 +468,7 @@ static const struct net_device_ops lan966x_port_netdev_ops = {
 	.ndo_get_port_parent_id		= lan966x_port_get_parent_id,
 	.ndo_eth_ioctl			= lan966x_port_ioctl,
 	.ndo_setup_tc			= lan966x_tc_setup,
+	.ndo_bpf			= lan966x_xdp,
 };
 
 bool lan966x_netdevice_check(const struct net_device *dev)
@@ -694,6 +695,7 @@ static void lan966x_cleanup_ports(struct lan966x *lan966x)
 		if (port->dev)
 			unregister_netdev(port->dev);
 
+		lan966x_xdp_port_deinit(port);
 		if (lan966x->fdma && lan966x->fdma_ndev == port->dev)
 			lan966x_fdma_netdev_deinit(lan966x, port->dev);
 
@@ -760,7 +762,7 @@ static int lan966x_probe_port(struct lan966x *lan966x, u32 p,
 			 NETIF_F_HW_VLAN_STAG_TX |
 			 NETIF_F_HW_TC;
 	dev->hw_features |= NETIF_F_HW_TC;
-	dev->needed_headroom = IFH_LEN * sizeof(u32);
+	dev->needed_headroom = IFH_LEN_BYTES;
 
 	eth_hw_addr_gen(dev, lan966x->base_mac, p + 1);
 
@@ -1136,6 +1138,9 @@ static int lan966x_probe(struct platform_device *pdev)
 		lan966x->ports[p]->serdes = serdes;
 
 		lan966x_port_init(lan966x->ports[p]);
+		err = lan966x_xdp_port_init(lan966x->ports[p]);
+		if (err)
+			goto cleanup_ports;
 	}
 
 	lan966x_mdb_init(lan966x);

drivers/net/ethernet/microchip/lan966x/lan966x_main.h

@@ -9,6 +9,7 @@
 #include <linux/phy.h>
 #include <linux/phylink.h>
 #include <linux/ptp_clock_kernel.h>
+#include <net/page_pool.h>
 #include <net/pkt_cls.h>
 #include <net/pkt_sched.h>
 #include <net/switchdev.h>
@@ -100,6 +101,17 @@ enum macaccess_entry_type {
 	ENTRYTYPE_MACV6,
 };
 
+/* FDMA return action codes for checking if the frame is valid
+ * FDMA_PASS, frame is valid and can be used
+ * FDMA_ERROR, something went wrong, stop getting more frames
+ * FDMA_DROP, frame is dropped, but continue to get more frames
+ */
+enum lan966x_fdma_action {
+	FDMA_PASS = 0,
+	FDMA_ERROR,
+	FDMA_DROP,
+};
+
 struct lan966x_port;
 
 struct lan966x_db {
@@ -150,7 +162,14 @@ struct lan966x_rx {
 	 */
 	u8 page_order;
 
+	/* Represents the max size frame that it can receive to the CPU. This
+	 * includes the IFH + VLAN tags + frame + skb_shared_info
+	 */
+	u32 max_mtu;
+
 	u8 channel_id;
+
+	struct page_pool *page_pool;
 };
 
 struct lan966x_tx_dcb_buf {
@@ -320,6 +339,9 @@ struct lan966x_port {
 	enum netdev_lag_hash hash_type;
 
 	struct lan966x_port_tc tc;
+
+	struct bpf_prog *xdp_prog;
+	struct xdp_rxq_info xdp_rxq;
 };
 
 extern const struct phylink_mac_ops lan966x_phylink_mac_ops;
@@ -527,6 +549,17 @@ void lan966x_mirror_port_stats(struct lan966x_port *port,
 			       struct flow_stats *stats,
 			       bool ingress);
 
+int lan966x_xdp_port_init(struct lan966x_port *port);
+void lan966x_xdp_port_deinit(struct lan966x_port *port);
+int lan966x_xdp(struct net_device *dev, struct netdev_bpf *xdp);
+int lan966x_xdp_run(struct lan966x_port *port,
+		    struct page *page,
+		    u32 data_len);
+static inline bool lan966x_xdp_port_present(struct lan966x_port *port)
+{
+	return !!port->xdp_prog;
+}
+
 static inline void __iomem *lan_addr(void __iomem *base[],
 				     int id, int tinst, int tcnt,
 				     int gbase, int ginst,

drivers/net/ethernet/microchip/lan966x/lan966x_xdp.c

+// SPDX-License-Identifier: GPL-2.0+
+
+#include <linux/bpf.h>
+#include <linux/bpf_trace.h>
+#include <linux/filter.h>
+
+#include "lan966x_main.h"
+
+static int lan966x_xdp_setup(struct net_device *dev, struct netdev_bpf *xdp)
+{
+	struct lan966x_port *port = netdev_priv(dev);
+	struct lan966x *lan966x = port->lan966x;
+	struct bpf_prog *old_prog;
+
+	if (!lan966x->fdma) {
+		NL_SET_ERR_MSG_MOD(xdp->extack,
+				   "Allow to set xdp only when using fdma");
+		return -EOPNOTSUPP;
+	}
+
+	old_prog = xchg(&port->xdp_prog, xdp->prog);
+	if (old_prog)
+		bpf_prog_put(old_prog);
+
+	return 0;
+}
+
+int lan966x_xdp(struct net_device *dev, struct netdev_bpf *xdp)
+{
+	switch (xdp->command) {
+	case XDP_SETUP_PROG:
+		return lan966x_xdp_setup(dev, xdp);
+	default:
+		return -EINVAL;
+	}
+}
+
+int lan966x_xdp_run(struct lan966x_port *port, struct page *page, u32 data_len)
+{
+	struct bpf_prog *xdp_prog = port->xdp_prog;
+	struct lan966x *lan966x = port->lan966x;
+	struct xdp_buff xdp;
+	u32 act;
+
+	xdp_init_buff(&xdp, PAGE_SIZE << lan966x->rx.page_order,
+		      &port->xdp_rxq);
+	xdp_prepare_buff(&xdp, page_address(page), IFH_LEN_BYTES,
+			 data_len - IFH_LEN_BYTES, false);
+	act = bpf_prog_run_xdp(xdp_prog, &xdp);
+	switch (act) {
+	case XDP_PASS:
+		return FDMA_PASS;
+	default:
+		bpf_warn_invalid_xdp_action(port->dev, xdp_prog, act);
+		fallthrough;
+	case XDP_ABORTED:
+		trace_xdp_exception(port->dev, xdp_prog, act);
+		fallthrough;
+	case XDP_DROP:
+		return FDMA_DROP;
+	}
+}
+
+int lan966x_xdp_port_init(struct lan966x_port *port)
+{
+	struct lan966x *lan966x = port->lan966x;
+
+	return xdp_rxq_info_reg(&port->xdp_rxq, port->dev, 0,
+				lan966x->napi.napi_id);
+}
+
+void lan966x_xdp_port_deinit(struct lan966x_port *port)
+{
+	if (xdp_rxq_info_is_reg(&port->xdp_rxq))
+		xdp_rxq_info_unreg(&port->xdp_rxq);
+}