net/dsa/tag_ocelot.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0
 /* Copyright 2019 NXP
  */
 #include <linux/dsa/ocelot.h>
 #include "dsa_priv.h"

 /* If the port is under a VLAN-aware bridge, remove the VLAN header from the
  * payload and move it into the DSA tag, which will make the switch classify
  * the packet to the bridge VLAN. Otherwise, leave the classified VLAN at zero,
  * which is the pvid of standalone and VLAN-unaware bridge ports.
  */
 static void ocelot_xmit_get_vlan_info(struct sk_buff *skb, struct dsa_port *dp,
 				      u64 *vlan_tci, u64 *tag_type)
 {
 	struct net_device *br = READ_ONCE(dp->bridge_dev);
 	struct vlan_ethhdr *hdr;
 	u16 proto, tci;

 	if (!br || !br_vlan_enabled(br)) {
 		*vlan_tci = 0;
 		*tag_type = IFH_TAG_TYPE_C;
 		return;
 	}

 	hdr = (struct vlan_ethhdr *)skb_mac_header(skb);
 	br_vlan_get_proto(br, &proto);

 	if (ntohs(hdr->h_vlan_proto) == proto) {
 		__skb_vlan_pop(skb, &tci);
 		*vlan_tci = tci;
 	} else {
 		rcu_read_lock();
 		br_vlan_get_pvid_rcu(br, &tci);
 		rcu_read_unlock();
 		*vlan_tci = tci;
 	}

 	*tag_type = (proto != ETH_P_8021Q) ? IFH_TAG_TYPE_S : IFH_TAG_TYPE_C;
 }

 static void ocelot_xmit_common(struct sk_buff *skb, struct net_device *netdev,
 			       __be32 ifh_prefix, void **ifh)
 {
 	struct dsa_port *dp = dsa_slave_to_port(netdev);
 	struct dsa_switch *ds = dp->ds;
 	u64 vlan_tci, tag_type;
 	void *injection;
 	__be32 *prefix;
 	u32 rew_op = 0;

 	ocelot_xmit_get_vlan_info(skb, dp, &vlan_tci, &tag_type);

 	injection = skb_push(skb, OCELOT_TAG_LEN);
 	prefix = skb_push(skb, OCELOT_SHORT_PREFIX_LEN);

 	*prefix = ifh_prefix;
 	memset(injection, 0, OCELOT_TAG_LEN);
 	ocelot_ifh_set_bypass(injection, 1);
 	ocelot_ifh_set_src(injection, ds->num_ports);
 	ocelot_ifh_set_qos_class(injection, skb->priority);
 	ocelot_ifh_set_vlan_tci(injection, vlan_tci);
 	ocelot_ifh_set_tag_type(injection, tag_type);

 	rew_op = ocelot_ptp_rew_op(skb);
 	if (rew_op)
 		ocelot_ifh_set_rew_op(injection, rew_op);

 	*ifh = injection;
 }

 static struct sk_buff *ocelot_xmit(struct sk_buff *skb,
 				   struct net_device *netdev)
 {
 	struct dsa_port *dp = dsa_slave_to_port(netdev);
 	void *injection;

 	ocelot_xmit_common(skb, netdev, cpu_to_be32(0x8880000a), &injection);
 	ocelot_ifh_set_dest(injection, BIT_ULL(dp->index));

 	return skb;
 }

 static struct sk_buff *seville_xmit(struct sk_buff *skb,
 				    struct net_device *netdev)
 {
 	struct dsa_port *dp = dsa_slave_to_port(netdev);
 	void *injection;

 	ocelot_xmit_common(skb, netdev, cpu_to_be32(0x88800005), &injection);
 	seville_ifh_set_dest(injection, BIT_ULL(dp->index));

 	return skb;
 }

 static struct sk_buff *ocelot_rcv(struct sk_buff *skb,
 				  struct net_device *netdev)
 {
 	u64 src_port, qos_class;
 	u64 vlan_tci, tag_type;
 	u8 *start = skb->data;
 	struct dsa_port *dp;
 	u8 *extraction;
 	u16 vlan_tpid;
 	u64 rew_val;

 	/* Revert skb->data by the amount consumed by the DSA master,
 	 * so it points to the beginning of the frame.
 	 */
 	skb_push(skb, ETH_HLEN);
 	/* We don't care about the short prefix, it is just for easy entrance
 	 * into the DSA master's RX filter. Discard it now by moving it into
 	 * the headroom.
 	 */
 	skb_pull(skb, OCELOT_SHORT_PREFIX_LEN);
 	/* And skb->data now points to the extraction frame header.
 	 * Keep a pointer to it.
 	 */
 	extraction = skb->data;
 	/* Now the EFH is part of the headroom as well */
 	skb_pull(skb, OCELOT_TAG_LEN);
 	/* Reset the pointer to the real MAC header */
 	skb_reset_mac_header(skb);
 	skb_reset_mac_len(skb);
 	/* And move skb->data to the correct location again */
 	skb_pull(skb, ETH_HLEN);

 	/* Remove from inet csum the extraction header */
 	skb_postpull_rcsum(skb, start, OCELOT_TOTAL_TAG_LEN);

 	ocelot_xfh_get_src_port(extraction, &src_port);
 	ocelot_xfh_get_qos_class(extraction, &qos_class);
 	ocelot_xfh_get_tag_type(extraction, &tag_type);
 	ocelot_xfh_get_vlan_tci(extraction, &vlan_tci);
 	ocelot_xfh_get_rew_val(extraction, &rew_val);

 	skb->dev = dsa_master_find_slave(netdev, 0, src_port);
 	if (!skb->dev)
 		/* The switch will reflect back some frames sent through
 		 * sockets opened on the bare DSA master. These will come back
 		 * with src_port equal to the index of the CPU port, for which
 		 * there is no slave registered. So don't print any error
 		 * message here (ignore and drop those frames).
 		 */
 		return NULL;

 	dsa_default_offload_fwd_mark(skb);
 	skb->priority = qos_class;
 	OCELOT_SKB_CB(skb)->tstamp_lo = rew_val;

 	/* Ocelot switches copy frames unmodified to the CPU. However, it is
 	 * possible for the user to request a VLAN modification through
 	 * VCAP_IS1_ACT_VID_REPLACE_ENA. In this case, what will happen is that
 	 * the VLAN ID field from the Extraction Header gets updated, but the
 	 * 802.1Q header does not (the classified VLAN only becomes visible on
 	 * egress through the "port tag" of front-panel ports).
 	 * So, for traffic extracted by the CPU, we want to pick up the
 	 * classified VLAN and manually replace the existing 802.1Q header from
 	 * the packet with it, so that the operating system is always up to
 	 * date with the result of tc-vlan actions.
 	 * NOTE: In VLAN-unaware mode, we don't want to do that, we want the
 	 * frame to remain unmodified, because the classified VLAN is always
 	 * equal to the pvid of the ingress port and should not be used for
 	 * processing.
 	 */
 	dp = dsa_slave_to_port(skb->dev);
 	vlan_tpid = tag_type ? ETH_P_8021AD : ETH_P_8021Q;

 	if (dsa_port_is_vlan_filtering(dp) &&
 	    eth_hdr(skb)->h_proto == htons(vlan_tpid)) {
 		u16 dummy_vlan_tci;

 		skb_push_rcsum(skb, ETH_HLEN);
 		__skb_vlan_pop(skb, &dummy_vlan_tci);
 		skb_pull_rcsum(skb, ETH_HLEN);
 		__vlan_hwaccel_put_tag(skb, htons(vlan_tpid), vlan_tci);
 	}

 	return skb;
 }

 static const struct dsa_device_ops ocelot_netdev_ops = {
 	.name			= "ocelot",
 	.proto			= DSA_TAG_PROTO_OCELOT,
 	.xmit			= ocelot_xmit,
 	.rcv			= ocelot_rcv,
 	.needed_headroom	= OCELOT_TOTAL_TAG_LEN,
 	.promisc_on_master	= true,
 };

 DSA_TAG_DRIVER(ocelot_netdev_ops);
 MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_OCELOT);

 static const struct dsa_device_ops seville_netdev_ops = {
 	.name			= "seville",
 	.proto			= DSA_TAG_PROTO_SEVILLE,
 	.xmit			= seville_xmit,
 	.rcv			= ocelot_rcv,
 	.needed_headroom	= OCELOT_TOTAL_TAG_LEN,
 	.promisc_on_master	= true,
 };

 DSA_TAG_DRIVER(seville_netdev_ops);
 MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_SEVILLE);

 static struct dsa_tag_driver *ocelot_tag_driver_array[] = {
 	&DSA_TAG_DRIVER_NAME(ocelot_netdev_ops),
 	&DSA_TAG_DRIVER_NAME(seville_netdev_ops),
 };

 module_dsa_tag_drivers(ocelot_tag_driver_array);

 MODULE_LICENSE("GPL v2");
	// SPDX-License-Identifier: GPL-2.0
	/* Copyright 2019 NXP
	*/
	#include <linux/dsa/ocelot.h>
	#include "dsa_priv.h"

	/* If the port is under a VLAN-aware bridge, remove the VLAN header from the
	* payload and move it into the DSA tag, which will make the switch classify
	* the packet to the bridge VLAN. Otherwise, leave the classified VLAN at zero,
	* which is the pvid of standalone and VLAN-unaware bridge ports.
	*/
	static void ocelot_xmit_get_vlan_info(struct sk_buff skb, struct dsa_port dp,
	u64 vlan_tci, u64 tag_type)
	{
	struct net_device *br = READ_ONCE(dp->bridge_dev);
	struct vlan_ethhdr *hdr;
	u16 proto, tci;

	if (!br \|\| !br_vlan_enabled(br)) {
	*vlan_tci = 0;
	*tag_type = IFH_TAG_TYPE_C;
	return;
	}

	hdr = (struct vlan_ethhdr *)skb_mac_header(skb);
	br_vlan_get_proto(br, &proto);

	if (ntohs(hdr->h_vlan_proto) == proto) {
	__skb_vlan_pop(skb, &tci);
	*vlan_tci = tci;
	} else {
	rcu_read_lock();
	br_vlan_get_pvid_rcu(br, &tci);
	rcu_read_unlock();
	*vlan_tci = tci;
	}

	*tag_type = (proto != ETH_P_8021Q) ? IFH_TAG_TYPE_S : IFH_TAG_TYPE_C;
	}

	static void ocelot_xmit_common(struct sk_buff skb, struct net_device netdev,
	__be32 ifh_prefix, void **ifh)
	{
	struct dsa_port *dp = dsa_slave_to_port(netdev);
	struct dsa_switch *ds = dp->ds;
	u64 vlan_tci, tag_type;
	void *injection;
	__be32 *prefix;
	u32 rew_op = 0;

	ocelot_xmit_get_vlan_info(skb, dp, &vlan_tci, &tag_type);

	injection = skb_push(skb, OCELOT_TAG_LEN);
	prefix = skb_push(skb, OCELOT_SHORT_PREFIX_LEN);

	*prefix = ifh_prefix;
	memset(injection, 0, OCELOT_TAG_LEN);
	ocelot_ifh_set_bypass(injection, 1);
	ocelot_ifh_set_src(injection, ds->num_ports);
	ocelot_ifh_set_qos_class(injection, skb->priority);
	ocelot_ifh_set_vlan_tci(injection, vlan_tci);
	ocelot_ifh_set_tag_type(injection, tag_type);

	rew_op = ocelot_ptp_rew_op(skb);
	if (rew_op)
	ocelot_ifh_set_rew_op(injection, rew_op);

	*ifh = injection;
	}

	static struct sk_buff ocelot_xmit(struct sk_buff skb,
	struct net_device *netdev)
	{
	struct dsa_port *dp = dsa_slave_to_port(netdev);
	void *injection;

	ocelot_xmit_common(skb, netdev, cpu_to_be32(0x8880000a), &injection);
	ocelot_ifh_set_dest(injection, BIT_ULL(dp->index));

	return skb;
	}

	static struct sk_buff seville_xmit(struct sk_buff skb,
	struct net_device *netdev)
	{
	struct dsa_port *dp = dsa_slave_to_port(netdev);
	void *injection;

	ocelot_xmit_common(skb, netdev, cpu_to_be32(0x88800005), &injection);
	seville_ifh_set_dest(injection, BIT_ULL(dp->index));

	return skb;
	}

	static struct sk_buff ocelot_rcv(struct sk_buff skb,
	struct net_device *netdev)
	{
	u64 src_port, qos_class;
	u64 vlan_tci, tag_type;
	u8 *start = skb->data;
	struct dsa_port *dp;
	u8 *extraction;
	u16 vlan_tpid;
	u64 rew_val;

	/* Revert skb->data by the amount consumed by the DSA master,
	* so it points to the beginning of the frame.
	*/
	skb_push(skb, ETH_HLEN);
	/* We don't care about the short prefix, it is just for easy entrance
	* into the DSA master's RX filter. Discard it now by moving it into
	* the headroom.
	*/
	skb_pull(skb, OCELOT_SHORT_PREFIX_LEN);
	/* And skb->data now points to the extraction frame header.
	* Keep a pointer to it.
	*/
	extraction = skb->data;
	/* Now the EFH is part of the headroom as well */
	skb_pull(skb, OCELOT_TAG_LEN);
	/* Reset the pointer to the real MAC header */
	skb_reset_mac_header(skb);
	skb_reset_mac_len(skb);
	/* And move skb->data to the correct location again */
	skb_pull(skb, ETH_HLEN);

	/* Remove from inet csum the extraction header */
	skb_postpull_rcsum(skb, start, OCELOT_TOTAL_TAG_LEN);

	ocelot_xfh_get_src_port(extraction, &src_port);
	ocelot_xfh_get_qos_class(extraction, &qos_class);
	ocelot_xfh_get_tag_type(extraction, &tag_type);
	ocelot_xfh_get_vlan_tci(extraction, &vlan_tci);
	ocelot_xfh_get_rew_val(extraction, &rew_val);

	skb->dev = dsa_master_find_slave(netdev, 0, src_port);
	if (!skb->dev)
	/* The switch will reflect back some frames sent through
	* sockets opened on the bare DSA master. These will come back
	* with src_port equal to the index of the CPU port, for which
	* there is no slave registered. So don't print any error
	* message here (ignore and drop those frames).
	*/
	return NULL;

	dsa_default_offload_fwd_mark(skb);
	skb->priority = qos_class;
	OCELOT_SKB_CB(skb)->tstamp_lo = rew_val;

	/* Ocelot switches copy frames unmodified to the CPU. However, it is
	* possible for the user to request a VLAN modification through
	* VCAP_IS1_ACT_VID_REPLACE_ENA. In this case, what will happen is that
	* the VLAN ID field from the Extraction Header gets updated, but the
	* 802.1Q header does not (the classified VLAN only becomes visible on
	* egress through the "port tag" of front-panel ports).
	* So, for traffic extracted by the CPU, we want to pick up the
	* classified VLAN and manually replace the existing 802.1Q header from
	* the packet with it, so that the operating system is always up to
	* date with the result of tc-vlan actions.
	* NOTE: In VLAN-unaware mode, we don't want to do that, we want the
	* frame to remain unmodified, because the classified VLAN is always
	* equal to the pvid of the ingress port and should not be used for
	* processing.
	*/
	dp = dsa_slave_to_port(skb->dev);
	vlan_tpid = tag_type ? ETH_P_8021AD : ETH_P_8021Q;

	if (dsa_port_is_vlan_filtering(dp) &&
	eth_hdr(skb)->h_proto == htons(vlan_tpid)) {
	u16 dummy_vlan_tci;

	skb_push_rcsum(skb, ETH_HLEN);
	__skb_vlan_pop(skb, &dummy_vlan_tci);
	skb_pull_rcsum(skb, ETH_HLEN);
	__vlan_hwaccel_put_tag(skb, htons(vlan_tpid), vlan_tci);
	}

	return skb;
	}

	static const struct dsa_device_ops ocelot_netdev_ops = {
	.name = "ocelot",
	.proto = DSA_TAG_PROTO_OCELOT,
	.xmit = ocelot_xmit,
	.rcv = ocelot_rcv,
	.needed_headroom = OCELOT_TOTAL_TAG_LEN,
	.promisc_on_master = true,
	};

	DSA_TAG_DRIVER(ocelot_netdev_ops);
	MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_OCELOT);

	static const struct dsa_device_ops seville_netdev_ops = {
	.name = "seville",
	.proto = DSA_TAG_PROTO_SEVILLE,
	.xmit = seville_xmit,
	.rcv = ocelot_rcv,
	.needed_headroom = OCELOT_TOTAL_TAG_LEN,
	.promisc_on_master = true,
	};

	DSA_TAG_DRIVER(seville_netdev_ops);
	MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_SEVILLE);

	static struct dsa_tag_driver *ocelot_tag_driver_array[] = {
	&DSA_TAG_DRIVER_NAME(ocelot_netdev_ops),
	&DSA_TAG_DRIVER_NAME(seville_netdev_ops),
	};

	module_dsa_tag_drivers(ocelot_tag_driver_array);

	MODULE_LICENSE("GPL v2");