Adding upstream version 6.1.76.upstream/6.1.76upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

12 files changed, 1981 insertions, 0 deletions

diff --git a/drivers/net/ethernet/qualcomm/rmnet/Kconfig b/drivers/net/ethernet/qualcomm/rmnet/Kconfig
new file mode 100644
index 000000000..b4a575eb0
--- /dev/null
+++ b/drivers/net/ethernet/qualcomm/rmnet/Kconfig
@@ -0,0 +1,14 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# RMNET MAP driver
+#
+
+menuconfig RMNET
+	tristate "RmNet MAP driver"
+	default n
+	select GRO_CELLS
+	help
+	  If you select this, you will enable the RMNET module which is used
+	  for handling data in the multiplexing and aggregation protocol (MAP)
+	  format in the embedded data path. RMNET devices can be attached to
+	  any IP mode physical device.
diff --git a/drivers/net/ethernet/qualcomm/rmnet/Makefile b/drivers/net/ethernet/qualcomm/rmnet/Makefile
new file mode 100644
index 000000000..8252e40bf
--- /dev/null
+++ b/drivers/net/ethernet/qualcomm/rmnet/Makefile
@@ -0,0 +1,11 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# Makefile for the RMNET module
+#
+
+rmnet-y		 := rmnet_config.o
+rmnet-y		 += rmnet_vnd.o
+rmnet-y		 += rmnet_handlers.o
+rmnet-y		 += rmnet_map_data.o
+rmnet-y		 += rmnet_map_command.o
+obj-$(CONFIG_RMNET) += rmnet.o
diff --git a/drivers/net/ethernet/qualcomm/rmnet/rmnet_config.c b/drivers/net/ethernet/qualcomm/rmnet/rmnet_config.c
new file mode 100644
index 000000000..64b209a0a
--- /dev/null
+++ b/drivers/net/ethernet/qualcomm/rmnet/rmnet_config.c
@@ -0,0 +1,518 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* Copyright (c) 2013-2018, The Linux Foundation. All rights reserved.
+ *
+ * RMNET configuration engine
+ */
+
+#include <net/sock.h>
+#include <linux/module.h>
+#include <linux/netlink.h>
+#include <linux/netdevice.h>
+#include "rmnet_config.h"
+#include "rmnet_handlers.h"
+#include "rmnet_vnd.h"
+#include "rmnet_private.h"
+
+/* Local Definitions and Declarations */
+
+static const struct nla_policy rmnet_policy[IFLA_RMNET_MAX + 1] = {
+	[IFLA_RMNET_MUX_ID]	= { .type = NLA_U16 },
+	[IFLA_RMNET_FLAGS]	= { .len = sizeof(struct ifla_rmnet_flags) },
+};
+
+static int rmnet_is_real_dev_registered(const struct net_device *real_dev)
+{
+	return rcu_access_pointer(real_dev->rx_handler) == rmnet_rx_handler;
+}
+
+/* Needs rtnl lock */
+struct rmnet_port*
+rmnet_get_port_rtnl(const struct net_device *real_dev)
+{
+	return rtnl_dereference(real_dev->rx_handler_data);
+}
+
+static int rmnet_unregister_real_device(struct net_device *real_dev)
+{
+	struct rmnet_port *port = rmnet_get_port_rtnl(real_dev);
+
+	if (port->nr_rmnet_devs)
+		return -EINVAL;
+
+	netdev_rx_handler_unregister(real_dev);
+
+	kfree(port);
+
+	netdev_dbg(real_dev, "Removed from rmnet\n");
+	return 0;
+}
+
+static int rmnet_register_real_device(struct net_device *real_dev,
+				      struct netlink_ext_ack *extack)
+{
+	struct rmnet_port *port;
+	int rc, entry;
+
+	ASSERT_RTNL();
+
+	if (rmnet_is_real_dev_registered(real_dev)) {
+		port = rmnet_get_port_rtnl(real_dev);
+		if (port->rmnet_mode != RMNET_EPMODE_VND) {
+			NL_SET_ERR_MSG_MOD(extack, "bridge device already exists");
+			return -EINVAL;
+		}
+
+		return 0;
+	}
+
+	port = kzalloc(sizeof(*port), GFP_KERNEL);
+	if (!port)
+		return -ENOMEM;
+
+	port->dev = real_dev;
+	rc = netdev_rx_handler_register(real_dev, rmnet_rx_handler, port);
+	if (rc) {
+		kfree(port);
+		return -EBUSY;
+	}
+
+	for (entry = 0; entry < RMNET_MAX_LOGICAL_EP; entry++)
+		INIT_HLIST_HEAD(&port->muxed_ep[entry]);
+
+	netdev_dbg(real_dev, "registered with rmnet\n");
+	return 0;
+}
+
+static void rmnet_unregister_bridge(struct rmnet_port *port)
+{
+	struct net_device *bridge_dev, *real_dev, *rmnet_dev;
+	struct rmnet_port *real_port;
+
+	if (port->rmnet_mode != RMNET_EPMODE_BRIDGE)
+		return;
+
+	rmnet_dev = port->rmnet_dev;
+	if (!port->nr_rmnet_devs) {
+		/* bridge device */
+		real_dev = port->bridge_ep;
+		bridge_dev = port->dev;
+
+		real_port = rmnet_get_port_rtnl(real_dev);
+		real_port->bridge_ep = NULL;
+		real_port->rmnet_mode = RMNET_EPMODE_VND;
+	} else {
+		/* real device */
+		bridge_dev = port->bridge_ep;
+
+		port->bridge_ep = NULL;
+		port->rmnet_mode = RMNET_EPMODE_VND;
+	}
+
+	netdev_upper_dev_unlink(bridge_dev, rmnet_dev);
+	rmnet_unregister_real_device(bridge_dev);
+}
+
+static int rmnet_newlink(struct net *src_net, struct net_device *dev,
+			 struct nlattr *tb[], struct nlattr *data[],
+			 struct netlink_ext_ack *extack)
+{
+	u32 data_format = RMNET_FLAGS_INGRESS_DEAGGREGATION;
+	struct net_device *real_dev;
+	int mode = RMNET_EPMODE_VND;
+	struct rmnet_endpoint *ep;
+	struct rmnet_port *port;
+	int err = 0;
+	u16 mux_id;
+
+	if (!tb[IFLA_LINK]) {
+		NL_SET_ERR_MSG_MOD(extack, "link not specified");
+		return -EINVAL;
+	}
+
+	real_dev = __dev_get_by_index(src_net, nla_get_u32(tb[IFLA_LINK]));
+	if (!real_dev) {
+		NL_SET_ERR_MSG_MOD(extack, "link does not exist");
+		return -ENODEV;
+	}
+
+	ep = kzalloc(sizeof(*ep), GFP_KERNEL);
+	if (!ep)
+		return -ENOMEM;
+
+	mux_id = nla_get_u16(data[IFLA_RMNET_MUX_ID]);
+
+	err = rmnet_register_real_device(real_dev, extack);
+	if (err)
+		goto err0;
+
+	port = rmnet_get_port_rtnl(real_dev);
+	err = rmnet_vnd_newlink(mux_id, dev, port, real_dev, ep, extack);
+	if (err)
+		goto err1;
+
+	err = netdev_upper_dev_link(real_dev, dev, extack);
+	if (err < 0)
+		goto err2;
+
+	port->rmnet_mode = mode;
+	port->rmnet_dev = dev;
+
+	hlist_add_head_rcu(&ep->hlnode, &port->muxed_ep[mux_id]);
+
+	if (data[IFLA_RMNET_FLAGS]) {
+		struct ifla_rmnet_flags *flags;
+
+		flags = nla_data(data[IFLA_RMNET_FLAGS]);
+		data_format &= ~flags->mask;
+		data_format |= flags->flags & flags->mask;
+	}
+
+	netdev_dbg(dev, "data format [0x%08X]\n", data_format);
+	port->data_format = data_format;
+
+	return 0;
+
+err2:
+	unregister_netdevice(dev);
+	rmnet_vnd_dellink(mux_id, port, ep);
+err1:
+	rmnet_unregister_real_device(real_dev);
+err0:
+	kfree(ep);
+	return err;
+}
+
+static void rmnet_dellink(struct net_device *dev, struct list_head *head)
+{
+	struct rmnet_priv *priv = netdev_priv(dev);
+	struct net_device *real_dev, *bridge_dev;
+	struct rmnet_port *real_port, *bridge_port;
+	struct rmnet_endpoint *ep;
+	u8 mux_id = priv->mux_id;
+
+	real_dev = priv->real_dev;
+
+	if (!rmnet_is_real_dev_registered(real_dev))
+		return;
+
+	real_port = rmnet_get_port_rtnl(real_dev);
+	bridge_dev = real_port->bridge_ep;
+	if (bridge_dev) {
+		bridge_port = rmnet_get_port_rtnl(bridge_dev);
+		rmnet_unregister_bridge(bridge_port);
+	}
+
+	ep = rmnet_get_endpoint(real_port, mux_id);
+	if (ep) {
+		hlist_del_init_rcu(&ep->hlnode);
+		rmnet_vnd_dellink(mux_id, real_port, ep);
+		kfree(ep);
+	}
+
+	netdev_upper_dev_unlink(real_dev, dev);
+	rmnet_unregister_real_device(real_dev);
+	unregister_netdevice_queue(dev, head);
+}
+
+static void rmnet_force_unassociate_device(struct net_device *real_dev)
+{
+	struct hlist_node *tmp_ep;
+	struct rmnet_endpoint *ep;
+	struct rmnet_port *port;
+	unsigned long bkt_ep;
+	LIST_HEAD(list);
+
+	port = rmnet_get_port_rtnl(real_dev);
+
+	if (port->nr_rmnet_devs) {
+		/* real device */
+		rmnet_unregister_bridge(port);
+		hash_for_each_safe(port->muxed_ep, bkt_ep, tmp_ep, ep, hlnode) {
+			unregister_netdevice_queue(ep->egress_dev, &list);
+			netdev_upper_dev_unlink(real_dev, ep->egress_dev);
+			rmnet_vnd_dellink(ep->mux_id, port, ep);
+			hlist_del_init_rcu(&ep->hlnode);
+			kfree(ep);
+		}
+		rmnet_unregister_real_device(real_dev);
+		unregister_netdevice_many(&list);
+	} else {
+		rmnet_unregister_bridge(port);
+	}
+}
+
+static int rmnet_config_notify_cb(struct notifier_block *nb,
+				  unsigned long event, void *data)
+{
+	struct net_device *real_dev = netdev_notifier_info_to_dev(data);
+
+	if (!rmnet_is_real_dev_registered(real_dev))
+		return NOTIFY_DONE;
+
+	switch (event) {
+	case NETDEV_UNREGISTER:
+		netdev_dbg(real_dev, "Kernel unregister\n");
+		rmnet_force_unassociate_device(real_dev);
+		break;
+	case NETDEV_CHANGEMTU:
+		if (rmnet_vnd_validate_real_dev_mtu(real_dev))
+			return NOTIFY_BAD;
+		break;
+	default:
+		break;
+	}
+
+	return NOTIFY_DONE;
+}
+
+static struct notifier_block rmnet_dev_notifier __read_mostly = {
+	.notifier_call = rmnet_config_notify_cb,
+};
+
+static int rmnet_rtnl_validate(struct nlattr *tb[], struct nlattr *data[],
+			       struct netlink_ext_ack *extack)
+{
+	u16 mux_id;
+
+	if (!data || !data[IFLA_RMNET_MUX_ID]) {
+		NL_SET_ERR_MSG_MOD(extack, "MUX ID not specified");
+		return -EINVAL;
+	}
+
+	mux_id = nla_get_u16(data[IFLA_RMNET_MUX_ID]);
+	if (mux_id > (RMNET_MAX_LOGICAL_EP - 1)) {
+		NL_SET_ERR_MSG_MOD(extack, "invalid MUX ID");
+		return -ERANGE;
+	}
+
+	return 0;
+}
+
+static int rmnet_changelink(struct net_device *dev, struct nlattr *tb[],
+			    struct nlattr *data[],
+			    struct netlink_ext_ack *extack)
+{
+	struct rmnet_priv *priv = netdev_priv(dev);
+	struct net_device *real_dev;
+	struct rmnet_port *port;
+	u16 mux_id;
+
+	if (!dev)
+		return -ENODEV;
+
+	real_dev = priv->real_dev;
+	if (!rmnet_is_real_dev_registered(real_dev))
+		return -ENODEV;
+
+	port = rmnet_get_port_rtnl(real_dev);
+
+	if (data[IFLA_RMNET_MUX_ID]) {
+		mux_id = nla_get_u16(data[IFLA_RMNET_MUX_ID]);
+
+		if (mux_id != priv->mux_id) {
+			struct rmnet_endpoint *ep;
+
+			ep = rmnet_get_endpoint(port, priv->mux_id);
+			if (!ep)
+				return -ENODEV;
+
+			if (rmnet_get_endpoint(port, mux_id)) {
+				NL_SET_ERR_MSG_MOD(extack,
+						   "MUX ID already exists");
+				return -EINVAL;
+			}
+
+			hlist_del_init_rcu(&ep->hlnode);
+			hlist_add_head_rcu(&ep->hlnode,
+					   &port->muxed_ep[mux_id]);
+
+			ep->mux_id = mux_id;
+			priv->mux_id = mux_id;
+		}
+	}
+
+	if (data[IFLA_RMNET_FLAGS]) {
+		struct ifla_rmnet_flags *flags;
+		u32 old_data_format;
+
+		old_data_format = port->data_format;
+		flags = nla_data(data[IFLA_RMNET_FLAGS]);
+		port->data_format &= ~flags->mask;
+		port->data_format |= flags->flags & flags->mask;
+
+		if (rmnet_vnd_update_dev_mtu(port, real_dev)) {
+			port->data_format = old_data_format;
+			NL_SET_ERR_MSG_MOD(extack, "Invalid MTU on real dev");
+			return -EINVAL;
+		}
+	}
+
+	return 0;
+}
+
+static size_t rmnet_get_size(const struct net_device *dev)
+{
+	return
+		/* IFLA_RMNET_MUX_ID */
+		nla_total_size(2) +
+		/* IFLA_RMNET_FLAGS */
+		nla_total_size(sizeof(struct ifla_rmnet_flags));
+}
+
+static int rmnet_fill_info(struct sk_buff *skb, const struct net_device *dev)
+{
+	struct rmnet_priv *priv = netdev_priv(dev);
+	struct net_device *real_dev;
+	struct ifla_rmnet_flags f;
+	struct rmnet_port *port;
+
+	real_dev = priv->real_dev;
+
+	if (nla_put_u16(skb, IFLA_RMNET_MUX_ID, priv->mux_id))
+		goto nla_put_failure;
+
+	if (rmnet_is_real_dev_registered(real_dev)) {
+		port = rmnet_get_port_rtnl(real_dev);
+		f.flags = port->data_format;
+	} else {
+		f.flags = 0;
+	}
+
+	f.mask  = ~0;
+
+	if (nla_put(skb, IFLA_RMNET_FLAGS, sizeof(f), &f))
+		goto nla_put_failure;
+
+	return 0;
+
+nla_put_failure:
+	return -EMSGSIZE;
+}
+
+struct rtnl_link_ops rmnet_link_ops __read_mostly = {
+	.kind		= "rmnet",
+	.maxtype	= IFLA_RMNET_MAX,
+	.priv_size	= sizeof(struct rmnet_priv),
+	.setup		= rmnet_vnd_setup,
+	.validate	= rmnet_rtnl_validate,
+	.newlink	= rmnet_newlink,
+	.dellink	= rmnet_dellink,
+	.get_size	= rmnet_get_size,
+	.changelink     = rmnet_changelink,
+	.policy		= rmnet_policy,
+	.fill_info	= rmnet_fill_info,
+};
+
+struct rmnet_port *rmnet_get_port_rcu(struct net_device *real_dev)
+{
+	if (rmnet_is_real_dev_registered(real_dev))
+		return rcu_dereference_bh(real_dev->rx_handler_data);
+	else
+		return NULL;
+}
+
+struct rmnet_endpoint *rmnet_get_endpoint(struct rmnet_port *port, u8 mux_id)
+{
+	struct rmnet_endpoint *ep;
+
+	hlist_for_each_entry_rcu(ep, &port->muxed_ep[mux_id], hlnode) {
+		if (ep->mux_id == mux_id)
+			return ep;
+	}
+
+	return NULL;
+}
+
+int rmnet_add_bridge(struct net_device *rmnet_dev,
+		     struct net_device *slave_dev,
+		     struct netlink_ext_ack *extack)
+{
+	struct rmnet_priv *priv = netdev_priv(rmnet_dev);
+	struct net_device *real_dev = priv->real_dev;
+	struct rmnet_port *port, *slave_port;
+	int err;
+
+	port = rmnet_get_port_rtnl(real_dev);
+
+	/* If there is more than one rmnet dev attached, its probably being
+	 * used for muxing. Skip the briding in that case
+	 */
+	if (port->nr_rmnet_devs > 1) {
+		NL_SET_ERR_MSG_MOD(extack, "more than one rmnet dev attached");
+		return -EINVAL;
+	}
+
+	if (port->rmnet_mode != RMNET_EPMODE_VND) {
+		NL_SET_ERR_MSG_MOD(extack, "more than one bridge dev attached");
+		return -EINVAL;
+	}
+
+	if (rmnet_is_real_dev_registered(slave_dev)) {
+		NL_SET_ERR_MSG_MOD(extack,
+				   "slave cannot be another rmnet dev");
+
+		return -EBUSY;
+	}
+
+	err = rmnet_register_real_device(slave_dev, extack);
+	if (err)
+		return -EBUSY;
+
+	err = netdev_master_upper_dev_link(slave_dev, rmnet_dev, NULL, NULL,
+					   extack);
+	if (err) {
+		rmnet_unregister_real_device(slave_dev);
+		return err;
+	}
+
+	slave_port = rmnet_get_port_rtnl(slave_dev);
+	slave_port->rmnet_mode = RMNET_EPMODE_BRIDGE;
+	slave_port->bridge_ep = real_dev;
+	slave_port->rmnet_dev = rmnet_dev;
+
+	port->rmnet_mode = RMNET_EPMODE_BRIDGE;
+	port->bridge_ep = slave_dev;
+
+	netdev_dbg(slave_dev, "registered with rmnet as slave\n");
+	return 0;
+}
+
+int rmnet_del_bridge(struct net_device *rmnet_dev,
+		     struct net_device *slave_dev)
+{
+	struct rmnet_port *port = rmnet_get_port_rtnl(slave_dev);
+
+	rmnet_unregister_bridge(port);
+
+	netdev_dbg(slave_dev, "removed from rmnet as slave\n");
+	return 0;
+}
+
+/* Startup/Shutdown */
+
+static int __init rmnet_init(void)
+{
+	int rc;
+
+	rc = register_netdevice_notifier(&rmnet_dev_notifier);
+	if (rc != 0)
+		return rc;
+
+	rc = rtnl_link_register(&rmnet_link_ops);
+	if (rc != 0) {
+		unregister_netdevice_notifier(&rmnet_dev_notifier);
+		return rc;
+	}
+	return rc;
+}
+
+static void __exit rmnet_exit(void)
+{
+	rtnl_link_unregister(&rmnet_link_ops);
+	unregister_netdevice_notifier(&rmnet_dev_notifier);
+}
+
+module_init(rmnet_init)
+module_exit(rmnet_exit)
+MODULE_ALIAS_RTNL_LINK("rmnet");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/net/ethernet/qualcomm/rmnet/rmnet_config.h b/drivers/net/ethernet/qualcomm/rmnet/rmnet_config.h
new file mode 100644
index 000000000..3d3cba56c
--- /dev/null
+++ b/drivers/net/ethernet/qualcomm/rmnet/rmnet_config.h
@@ -0,0 +1,81 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/* Copyright (c) 2013-2014, 2016-2018, 2021 The Linux Foundation.
+ * All rights reserved.
+ *
+ * RMNET Data configuration engine
+ */
+
+#include <linux/skbuff.h>
+#include <net/gro_cells.h>
+
+#ifndef _RMNET_CONFIG_H_
+#define _RMNET_CONFIG_H_
+
+#define RMNET_MAX_LOGICAL_EP 255
+
+struct rmnet_endpoint {
+	u8 mux_id;
+	struct net_device *egress_dev;
+	struct hlist_node hlnode;
+};
+
+/* One instance of this structure is instantiated for each real_dev associated
+ * with rmnet.
+ */
+struct rmnet_port {
+	struct net_device *dev;
+	u32 data_format;
+	u8 nr_rmnet_devs;
+	u8 rmnet_mode;
+	struct hlist_head muxed_ep[RMNET_MAX_LOGICAL_EP];
+	struct net_device *bridge_ep;
+	struct net_device *rmnet_dev;
+};
+
+extern struct rtnl_link_ops rmnet_link_ops;
+
+struct rmnet_vnd_stats {
+	u64 rx_pkts;
+	u64 rx_bytes;
+	u64 tx_pkts;
+	u64 tx_bytes;
+	u32 tx_drops;
+};
+
+struct rmnet_pcpu_stats {
+	struct rmnet_vnd_stats stats;
+	struct u64_stats_sync syncp;
+};
+
+struct rmnet_priv_stats {
+	u64 csum_ok;
+	u64 csum_ip4_header_bad;
+	u64 csum_valid_unset;
+	u64 csum_validation_failed;
+	u64 csum_err_bad_buffer;
+	u64 csum_err_invalid_ip_version;
+	u64 csum_err_invalid_transport;
+	u64 csum_fragmented_pkt;
+	u64 csum_skipped;
+	u64 csum_sw;
+	u64 csum_hw;
+};
+
+struct rmnet_priv {
+	u8 mux_id;
+	struct net_device *real_dev;
+	struct rmnet_pcpu_stats __percpu *pcpu_stats;
+	struct gro_cells gro_cells;
+	struct rmnet_priv_stats stats;
+};
+
+struct rmnet_port *rmnet_get_port_rcu(struct net_device *real_dev);
+struct rmnet_endpoint *rmnet_get_endpoint(struct rmnet_port *port, u8 mux_id);
+int rmnet_add_bridge(struct net_device *rmnet_dev,
+		     struct net_device *slave_dev,
+		     struct netlink_ext_ack *extack);
+int rmnet_del_bridge(struct net_device *rmnet_dev,
+		     struct net_device *slave_dev);
+struct rmnet_port*
+rmnet_get_port_rtnl(const struct net_device *real_dev);
+#endif /* _RMNET_CONFIG_H_ */
diff --git a/drivers/net/ethernet/qualcomm/rmnet/rmnet_handlers.c b/drivers/net/ethernet/qualcomm/rmnet/rmnet_handlers.c
new file mode 100644
index 000000000..a313242a7
--- /dev/null
+++ b/drivers/net/ethernet/qualcomm/rmnet/rmnet_handlers.c
@@ -0,0 +1,261 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* Copyright (c) 2013-2018, 2021, The Linux Foundation. All rights reserved.
+ *
+ * RMNET Data ingress/egress handler
+ */
+
+#include <linux/netdevice.h>
+#include <linux/netdev_features.h>
+#include <linux/if_arp.h>
+#include <net/sock.h>
+#include "rmnet_private.h"
+#include "rmnet_config.h"
+#include "rmnet_vnd.h"
+#include "rmnet_map.h"
+#include "rmnet_handlers.h"
+
+#define RMNET_IP_VERSION_4 0x40
+#define RMNET_IP_VERSION_6 0x60
+
+/* Helper Functions */
+
+static void rmnet_set_skb_proto(struct sk_buff *skb)
+{
+	switch (skb->data[0] & 0xF0) {
+	case RMNET_IP_VERSION_4:
+		skb->protocol = htons(ETH_P_IP);
+		break;
+	case RMNET_IP_VERSION_6:
+		skb->protocol = htons(ETH_P_IPV6);
+		break;
+	default:
+		skb->protocol = htons(ETH_P_MAP);
+		break;
+	}
+}
+
+/* Generic handler */
+
+static void
+rmnet_deliver_skb(struct sk_buff *skb)
+{
+	struct rmnet_priv *priv = netdev_priv(skb->dev);
+
+	skb_reset_transport_header(skb);
+	skb_reset_network_header(skb);
+	rmnet_vnd_rx_fixup(skb, skb->dev);
+
+	skb->pkt_type = PACKET_HOST;
+	skb_set_mac_header(skb, 0);
+	gro_cells_receive(&priv->gro_cells, skb);
+}
+
+/* MAP handler */
+
+static void
+__rmnet_map_ingress_handler(struct sk_buff *skb,
+			    struct rmnet_port *port)
+{
+	struct rmnet_map_header *map_header = (void *)skb->data;
+	struct rmnet_endpoint *ep;
+	u16 len, pad;
+	u8 mux_id;
+
+	if (map_header->flags & MAP_CMD_FLAG) {
+		/* Packet contains a MAP command (not data) */
+		if (port->data_format & RMNET_FLAGS_INGRESS_MAP_COMMANDS)
+			return rmnet_map_command(skb, port);
+
+		goto free_skb;
+	}
+
+	mux_id = map_header->mux_id;
+	pad = map_header->flags & MAP_PAD_LEN_MASK;
+	len = ntohs(map_header->pkt_len) - pad;
+
+	if (mux_id >= RMNET_MAX_LOGICAL_EP)
+		goto free_skb;
+
+	ep = rmnet_get_endpoint(port, mux_id);
+	if (!ep)
+		goto free_skb;
+
+	skb->dev = ep->egress_dev;
+
+	if ((port->data_format & RMNET_FLAGS_INGRESS_MAP_CKSUMV5) &&
+	    (map_header->flags & MAP_NEXT_HEADER_FLAG)) {
+		if (rmnet_map_process_next_hdr_packet(skb, len))
+			goto free_skb;
+		skb_pull(skb, sizeof(*map_header));
+		rmnet_set_skb_proto(skb);
+	} else {
+		/* Subtract MAP header */
+		skb_pull(skb, sizeof(*map_header));
+		rmnet_set_skb_proto(skb);
+		if (port->data_format & RMNET_FLAGS_INGRESS_MAP_CKSUMV4 &&
+		    !rmnet_map_checksum_downlink_packet(skb, len + pad))
+			skb->ip_summed = CHECKSUM_UNNECESSARY;
+	}
+
+	skb_trim(skb, len);
+	rmnet_deliver_skb(skb);
+	return;
+
+free_skb:
+	kfree_skb(skb);
+}
+
+static void
+rmnet_map_ingress_handler(struct sk_buff *skb,
+			  struct rmnet_port *port)
+{
+	struct sk_buff *skbn;
+
+	if (skb->dev->type == ARPHRD_ETHER) {
+		if (pskb_expand_head(skb, ETH_HLEN, 0, GFP_ATOMIC)) {
+			kfree_skb(skb);
+			return;
+		}
+
+		skb_push(skb, ETH_HLEN);
+	}
+
+	if (port->data_format & RMNET_FLAGS_INGRESS_DEAGGREGATION) {
+		while ((skbn = rmnet_map_deaggregate(skb, port)) != NULL)
+			__rmnet_map_ingress_handler(skbn, port);
+
+		consume_skb(skb);
+	} else {
+		__rmnet_map_ingress_handler(skb, port);
+	}
+}
+
+static int rmnet_map_egress_handler(struct sk_buff *skb,
+				    struct rmnet_port *port, u8 mux_id,
+				    struct net_device *orig_dev)
+{
+	int required_headroom, additional_header_len, csum_type = 0;
+	struct rmnet_map_header *map_header;
+
+	additional_header_len = 0;
+	required_headroom = sizeof(struct rmnet_map_header);
+
+	if (port->data_format & RMNET_FLAGS_EGRESS_MAP_CKSUMV4) {
+		additional_header_len = sizeof(struct rmnet_map_ul_csum_header);
+		csum_type = RMNET_FLAGS_EGRESS_MAP_CKSUMV4;
+	} else if (port->data_format & RMNET_FLAGS_EGRESS_MAP_CKSUMV5) {
+		additional_header_len = sizeof(struct rmnet_map_v5_csum_header);
+		csum_type = RMNET_FLAGS_EGRESS_MAP_CKSUMV5;
+	}
+
+	required_headroom += additional_header_len;
+
+	if (skb_cow_head(skb, required_headroom) < 0)
+		return -ENOMEM;
+
+	if (csum_type)
+		rmnet_map_checksum_uplink_packet(skb, port, orig_dev,
+						 csum_type);
+
+	map_header = rmnet_map_add_map_header(skb, additional_header_len,
+					      port, 0);
+	if (!map_header)
+		return -ENOMEM;
+
+	map_header->mux_id = mux_id;
+
+	skb->protocol = htons(ETH_P_MAP);
+
+	return 0;
+}
+
+static void
+rmnet_bridge_handler(struct sk_buff *skb, struct net_device *bridge_dev)
+{
+	if (skb_mac_header_was_set(skb))
+		skb_push(skb, skb->mac_len);
+
+	if (bridge_dev) {
+		skb->dev = bridge_dev;
+		dev_queue_xmit(skb);
+	}
+}
+
+/* Ingress / Egress Entry Points */
+
+/* Processes packet as per ingress data format for receiving device. Logical
+ * endpoint is determined from packet inspection. Packet is then sent to the
+ * egress device listed in the logical endpoint configuration.
+ */
+rx_handler_result_t rmnet_rx_handler(struct sk_buff **pskb)
+{
+	struct sk_buff *skb = *pskb;
+	struct rmnet_port *port;
+	struct net_device *dev;
+
+	if (!skb)
+		goto done;
+
+	if (skb_linearize(skb)) {
+		kfree_skb(skb);
+		goto done;
+	}
+
+	if (skb->pkt_type == PACKET_LOOPBACK)
+		return RX_HANDLER_PASS;
+
+	dev = skb->dev;
+	port = rmnet_get_port_rcu(dev);
+	if (unlikely(!port)) {
+		dev_core_stats_rx_nohandler_inc(skb->dev);
+		kfree_skb(skb);
+		goto done;
+	}
+
+	switch (port->rmnet_mode) {
+	case RMNET_EPMODE_VND:
+		rmnet_map_ingress_handler(skb, port);
+		break;
+	case RMNET_EPMODE_BRIDGE:
+		rmnet_bridge_handler(skb, port->bridge_ep);
+		break;
+	}
+
+done:
+	return RX_HANDLER_CONSUMED;
+}
+
+/* Modifies packet as per logical endpoint configuration and egress data format
+ * for egress device configured in logical endpoint. Packet is then transmitted
+ * on the egress device.
+ */
+void rmnet_egress_handler(struct sk_buff *skb)
+{
+	struct net_device *orig_dev;
+	struct rmnet_port *port;
+	struct rmnet_priv *priv;
+	u8 mux_id;
+
+	sk_pacing_shift_update(skb->sk, 8);
+
+	orig_dev = skb->dev;
+	priv = netdev_priv(orig_dev);
+	skb->dev = priv->real_dev;
+	mux_id = priv->mux_id;
+
+	port = rmnet_get_port_rcu(skb->dev);
+	if (!port)
+		goto drop;
+
+	if (rmnet_map_egress_handler(skb, port, mux_id, orig_dev))
+		goto drop;
+
+	rmnet_vnd_tx_fixup(skb, orig_dev);
+
+	dev_queue_xmit(skb);
+	return;
+
+drop:
+	this_cpu_inc(priv->pcpu_stats->stats.tx_drops);
+	kfree_skb(skb);
+}
diff --git a/drivers/net/ethernet/qualcomm/rmnet/rmnet_handlers.h b/drivers/net/ethernet/qualcomm/rmnet/rmnet_handlers.h
new file mode 100644
index 000000000..c4571dc32
--- /dev/null
+++ b/drivers/net/ethernet/qualcomm/rmnet/rmnet_handlers.h
@@ -0,0 +1,16 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/* Copyright (c) 2013, 2016-2017 The Linux Foundation. All rights reserved.
+ *
+ * RMNET Data ingress/egress handler
+ */
+
+#ifndef _RMNET_HANDLERS_H_
+#define _RMNET_HANDLERS_H_
+
+#include "rmnet_config.h"
+
+void rmnet_egress_handler(struct sk_buff *skb);
+
+rx_handler_result_t rmnet_rx_handler(struct sk_buff **pskb);
+
+#endif /* _RMNET_HANDLERS_H_ */
diff --git a/drivers/net/ethernet/qualcomm/rmnet/rmnet_map.h b/drivers/net/ethernet/qualcomm/rmnet/rmnet_map.h
new file mode 100644
index 000000000..2b033060f
--- /dev/null
+++ b/drivers/net/ethernet/qualcomm/rmnet/rmnet_map.h
@@ -0,0 +1,57 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/* Copyright (c) 2013-2018, 2021, The Linux Foundation. All rights reserved.
+ */
+
+#ifndef _RMNET_MAP_H_
+#define _RMNET_MAP_H_
+#include <linux/if_rmnet.h>
+
+struct rmnet_map_control_command {
+	u8  command_name;
+	u8  cmd_type:2;
+	u8  reserved:6;
+	u16 reserved2;
+	u32 transaction_id;
+	union {
+		struct {
+			u16 ip_family:2;
+			u16 reserved:14;
+			__be16 flow_control_seq_num;
+			__be32 qos_id;
+		} flow_control;
+		DECLARE_FLEX_ARRAY(u8, data);
+	};
+}  __aligned(1);
+
+enum rmnet_map_commands {
+	RMNET_MAP_COMMAND_NONE,
+	RMNET_MAP_COMMAND_FLOW_DISABLE,
+	RMNET_MAP_COMMAND_FLOW_ENABLE,
+	/* These should always be the last 2 elements */
+	RMNET_MAP_COMMAND_UNKNOWN,
+	RMNET_MAP_COMMAND_ENUM_LENGTH
+};
+
+#define RMNET_MAP_COMMAND_REQUEST     0
+#define RMNET_MAP_COMMAND_ACK         1
+#define RMNET_MAP_COMMAND_UNSUPPORTED 2
+#define RMNET_MAP_COMMAND_INVALID     3
+
+#define RMNET_MAP_NO_PAD_BYTES        0
+#define RMNET_MAP_ADD_PAD_BYTES       1
+
+struct sk_buff *rmnet_map_deaggregate(struct sk_buff *skb,
+				      struct rmnet_port *port);
+struct rmnet_map_header *rmnet_map_add_map_header(struct sk_buff *skb,
+						  int hdrlen,
+						  struct rmnet_port *port,
+						  int pad);
+void rmnet_map_command(struct sk_buff *skb, struct rmnet_port *port);
+int rmnet_map_checksum_downlink_packet(struct sk_buff *skb, u16 len);
+void rmnet_map_checksum_uplink_packet(struct sk_buff *skb,
+				      struct rmnet_port *port,
+				      struct net_device *orig_dev,
+				      int csum_type);
+int rmnet_map_process_next_hdr_packet(struct sk_buff *skb, u16 len);
+
+#endif /* _RMNET_MAP_H_ */
diff --git a/drivers/net/ethernet/qualcomm/rmnet/rmnet_map_command.c b/drivers/net/ethernet/qualcomm/rmnet/rmnet_map_command.c
new file mode 100644
index 000000000..add0f5ade
--- /dev/null
+++ b/drivers/net/ethernet/qualcomm/rmnet/rmnet_map_command.c
@@ -0,0 +1,102 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* Copyright (c) 2013-2018, The Linux Foundation. All rights reserved.
+ */
+
+#include <linux/netdevice.h>
+#include "rmnet_config.h"
+#include "rmnet_map.h"
+#include "rmnet_private.h"
+#include "rmnet_vnd.h"
+
+static u8 rmnet_map_do_flow_control(struct sk_buff *skb,
+				    struct rmnet_port *port,
+				    int enable)
+{
+	struct rmnet_map_header *map_header = (void *)skb->data;
+	struct rmnet_endpoint *ep;
+	struct net_device *vnd;
+	u8 mux_id;
+	int r;
+
+	mux_id = map_header->mux_id;
+
+	if (mux_id >= RMNET_MAX_LOGICAL_EP) {
+		kfree_skb(skb);
+		return RX_HANDLER_CONSUMED;
+	}
+
+	ep = rmnet_get_endpoint(port, mux_id);
+	if (!ep) {
+		kfree_skb(skb);
+		return RX_HANDLER_CONSUMED;
+	}
+
+	vnd = ep->egress_dev;
+
+	/* Ignore the ip family and pass the sequence number for both v4 and v6
+	 * sequence. User space does not support creating dedicated flows for
+	 * the 2 protocols
+	 */
+	r = rmnet_vnd_do_flow_control(vnd, enable);
+	if (r) {
+		kfree_skb(skb);
+		return RMNET_MAP_COMMAND_UNSUPPORTED;
+	} else {
+		return RMNET_MAP_COMMAND_ACK;
+	}
+}
+
+static void rmnet_map_send_ack(struct sk_buff *skb,
+			       unsigned char type,
+			       struct rmnet_port *port)
+{
+	struct rmnet_map_header *map_header = (void *)skb->data;
+	struct rmnet_map_control_command *cmd;
+	struct net_device *dev = skb->dev;
+
+	if (port->data_format & RMNET_FLAGS_INGRESS_MAP_CKSUMV4)
+		skb_trim(skb,
+			 skb->len - sizeof(struct rmnet_map_dl_csum_trailer));
+
+	skb->protocol = htons(ETH_P_MAP);
+
+	/* Command data immediately follows the MAP header */
+	cmd = (struct rmnet_map_control_command *)(map_header + 1);
+	cmd->cmd_type = type & 0x03;
+
+	netif_tx_lock(dev);
+	dev->netdev_ops->ndo_start_xmit(skb, dev);
+	netif_tx_unlock(dev);
+}
+
+/* Process MAP command frame and send N/ACK message as appropriate. Message cmd
+ * name is decoded here and appropriate handler is called.
+ */
+void rmnet_map_command(struct sk_buff *skb, struct rmnet_port *port)
+{
+	struct rmnet_map_header *map_header = (void *)skb->data;
+	struct rmnet_map_control_command *cmd;
+	unsigned char command_name;
+	unsigned char rc = 0;
+
+	/* Command data immediately follows the MAP header */
+	cmd = (struct rmnet_map_control_command *)(map_header + 1);
+	command_name = cmd->command_name;
+
+	switch (command_name) {
+	case RMNET_MAP_COMMAND_FLOW_ENABLE:
+		rc = rmnet_map_do_flow_control(skb, port, 1);
+		break;
+
+	case RMNET_MAP_COMMAND_FLOW_DISABLE:
+		rc = rmnet_map_do_flow_control(skb, port, 0);
+		break;
+
+	default:
+		rc = RMNET_MAP_COMMAND_UNSUPPORTED;
+		kfree_skb(skb);
+		break;
+	}
+	if (rc == RMNET_MAP_COMMAND_ACK)
+		rmnet_map_send_ack(skb, rc, port);
+}
diff --git a/drivers/net/ethernet/qualcomm/rmnet/rmnet_map_data.c b/drivers/net/ethernet/qualcomm/rmnet/rmnet_map_data.c
new file mode 100644
index 000000000..ba194698c
--- /dev/null
+++ b/drivers/net/ethernet/qualcomm/rmnet/rmnet_map_data.c
@@ -0,0 +1,520 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* Copyright (c) 2013-2018, 2021, The Linux Foundation. All rights reserved.
+ *
+ * RMNET Data MAP protocol
+ */
+
+#include <linux/netdevice.h>
+#include <linux/ip.h>
+#include <linux/ipv6.h>
+#include <net/ip6_checksum.h>
+#include <linux/bitfield.h>
+#include "rmnet_config.h"
+#include "rmnet_map.h"
+#include "rmnet_private.h"
+
+#define RMNET_MAP_DEAGGR_SPACING  64
+#define RMNET_MAP_DEAGGR_HEADROOM (RMNET_MAP_DEAGGR_SPACING / 2)
+
+static __sum16 *rmnet_map_get_csum_field(unsigned char protocol,
+					 const void *txporthdr)
+{
+	if (protocol == IPPROTO_TCP)
+		return &((struct tcphdr *)txporthdr)->check;
+
+	if (protocol == IPPROTO_UDP)
+		return &((struct udphdr *)txporthdr)->check;
+
+	return NULL;
+}
+
+static int
+rmnet_map_ipv4_dl_csum_trailer(struct sk_buff *skb,
+			       struct rmnet_map_dl_csum_trailer *csum_trailer,
+			       struct rmnet_priv *priv)
+{
+	struct iphdr *ip4h = (struct iphdr *)skb->data;
+	void *txporthdr = skb->data + ip4h->ihl * 4;
+	__sum16 *csum_field, pseudo_csum;
+	__sum16 ip_payload_csum;
+
+	/* Computing the checksum over just the IPv4 header--including its
+	 * checksum field--should yield 0.  If it doesn't, the IP header
+	 * is bad, so return an error and let the IP layer drop it.
+	 */
+	if (ip_fast_csum(ip4h, ip4h->ihl)) {
+		priv->stats.csum_ip4_header_bad++;
+		return -EINVAL;
+	}
+
+	/* We don't support checksum offload on IPv4 fragments */
+	if (ip_is_fragment(ip4h)) {
+		priv->stats.csum_fragmented_pkt++;
+		return -EOPNOTSUPP;
+	}
+
+	/* Checksum offload is only supported for UDP and TCP protocols */
+	csum_field = rmnet_map_get_csum_field(ip4h->protocol, txporthdr);
+	if (!csum_field) {
+		priv->stats.csum_err_invalid_transport++;
+		return -EPROTONOSUPPORT;
+	}
+
+	/* RFC 768: UDP checksum is optional for IPv4, and is 0 if unused */
+	if (!*csum_field && ip4h->protocol == IPPROTO_UDP) {
+		priv->stats.csum_skipped++;
+		return 0;
+	}
+
+	/* The checksum value in the trailer is computed over the entire
+	 * IP packet, including the IP header and payload.  To derive the
+	 * transport checksum from this, we first subract the contribution
+	 * of the IP header from the trailer checksum.  We then add the
+	 * checksum computed over the pseudo header.
+	 *
+	 * We verified above that the IP header contributes zero to the
+	 * trailer checksum.  Therefore the checksum in the trailer is
+	 * just the checksum computed over the IP payload.
+
+	 * If the IP payload arrives intact, adding the pseudo header
+	 * checksum to the IP payload checksum will yield 0xffff (negative
+	 * zero).  This means the trailer checksum and the pseudo checksum
+	 * are additive inverses of each other.  Put another way, the
+	 * message passes the checksum test if the trailer checksum value
+	 * is the negated pseudo header checksum.
+	 *
+	 * Knowing this, we don't even need to examine the transport
+	 * header checksum value; it is already accounted for in the
+	 * checksum value found in the trailer.
+	 */
+	ip_payload_csum = csum_trailer->csum_value;
+
+	pseudo_csum = csum_tcpudp_magic(ip4h->saddr, ip4h->daddr,
+					ntohs(ip4h->tot_len) - ip4h->ihl * 4,
+					ip4h->protocol, 0);
+
+	/* The cast is required to ensure only the low 16 bits are examined */
+	if (ip_payload_csum != (__sum16)~pseudo_csum) {
+		priv->stats.csum_validation_failed++;
+		return -EINVAL;
+	}
+
+	priv->stats.csum_ok++;
+	return 0;
+}
+
+#if IS_ENABLED(CONFIG_IPV6)
+static int
+rmnet_map_ipv6_dl_csum_trailer(struct sk_buff *skb,
+			       struct rmnet_map_dl_csum_trailer *csum_trailer,
+			       struct rmnet_priv *priv)
+{
+	struct ipv6hdr *ip6h = (struct ipv6hdr *)skb->data;
+	void *txporthdr = skb->data + sizeof(*ip6h);
+	__sum16 *csum_field, pseudo_csum;
+	__sum16 ip6_payload_csum;
+	__be16 ip_header_csum;
+
+	/* Checksum offload is only supported for UDP and TCP protocols;
+	 * the packet cannot include any IPv6 extension headers
+	 */
+	csum_field = rmnet_map_get_csum_field(ip6h->nexthdr, txporthdr);
+	if (!csum_field) {
+		priv->stats.csum_err_invalid_transport++;
+		return -EPROTONOSUPPORT;
+	}
+
+	/* The checksum value in the trailer is computed over the entire
+	 * IP packet, including the IP header and payload.  To derive the
+	 * transport checksum from this, we first subract the contribution
+	 * of the IP header from the trailer checksum.  We then add the
+	 * checksum computed over the pseudo header.
+	 */
+	ip_header_csum = (__force __be16)ip_fast_csum(ip6h, sizeof(*ip6h) / 4);
+	ip6_payload_csum = csum16_sub(csum_trailer->csum_value, ip_header_csum);
+
+	pseudo_csum = csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr,
+				      ntohs(ip6h->payload_len),
+				      ip6h->nexthdr, 0);
+
+	/* It's sufficient to compare the IP payload checksum with the
+	 * negated pseudo checksum to determine whether the packet
+	 * checksum was good.  (See further explanation in comments
+	 * in rmnet_map_ipv4_dl_csum_trailer()).
+	 *
+	 * The cast is required to ensure only the low 16 bits are
+	 * examined.
+	 */
+	if (ip6_payload_csum != (__sum16)~pseudo_csum) {
+		priv->stats.csum_validation_failed++;
+		return -EINVAL;
+	}
+
+	priv->stats.csum_ok++;
+	return 0;
+}
+#else
+static int
+rmnet_map_ipv6_dl_csum_trailer(struct sk_buff *skb,
+			       struct rmnet_map_dl_csum_trailer *csum_trailer,
+			       struct rmnet_priv *priv)
+{
+	return 0;
+}
+#endif
+
+static void rmnet_map_complement_ipv4_txporthdr_csum_field(struct iphdr *ip4h)
+{
+	void *txphdr;
+	u16 *csum;
+
+	txphdr = (void *)ip4h + ip4h->ihl * 4;
+
+	if (ip4h->protocol == IPPROTO_TCP || ip4h->protocol == IPPROTO_UDP) {
+		csum = (u16 *)rmnet_map_get_csum_field(ip4h->protocol, txphdr);
+		*csum = ~(*csum);
+	}
+}
+
+static void
+rmnet_map_ipv4_ul_csum_header(struct iphdr *iphdr,
+			      struct rmnet_map_ul_csum_header *ul_header,
+			      struct sk_buff *skb)
+{
+	u16 val;
+
+	val = MAP_CSUM_UL_ENABLED_FLAG;
+	if (iphdr->protocol == IPPROTO_UDP)
+		val |= MAP_CSUM_UL_UDP_FLAG;
+	val |= skb->csum_offset & MAP_CSUM_UL_OFFSET_MASK;
+
+	ul_header->csum_start_offset = htons(skb_network_header_len(skb));
+	ul_header->csum_info = htons(val);
+
+	skb->ip_summed = CHECKSUM_NONE;
+
+	rmnet_map_complement_ipv4_txporthdr_csum_field(iphdr);
+}
+
+#if IS_ENABLED(CONFIG_IPV6)
+static void
+rmnet_map_complement_ipv6_txporthdr_csum_field(struct ipv6hdr *ip6h)
+{
+	void *txphdr;
+	u16 *csum;
+
+	txphdr = ip6h + 1;
+
+	if (ip6h->nexthdr == IPPROTO_TCP || ip6h->nexthdr == IPPROTO_UDP) {
+		csum = (u16 *)rmnet_map_get_csum_field(ip6h->nexthdr, txphdr);
+		*csum = ~(*csum);
+	}
+}
+
+static void
+rmnet_map_ipv6_ul_csum_header(struct ipv6hdr *ipv6hdr,
+			      struct rmnet_map_ul_csum_header *ul_header,
+			      struct sk_buff *skb)
+{
+	u16 val;
+
+	val = MAP_CSUM_UL_ENABLED_FLAG;
+	if (ipv6hdr->nexthdr == IPPROTO_UDP)
+		val |= MAP_CSUM_UL_UDP_FLAG;
+	val |= skb->csum_offset & MAP_CSUM_UL_OFFSET_MASK;
+
+	ul_header->csum_start_offset = htons(skb_network_header_len(skb));
+	ul_header->csum_info = htons(val);
+
+	skb->ip_summed = CHECKSUM_NONE;
+
+	rmnet_map_complement_ipv6_txporthdr_csum_field(ipv6hdr);
+}
+#else
+static void
+rmnet_map_ipv6_ul_csum_header(void *ip6hdr,
+			      struct rmnet_map_ul_csum_header *ul_header,
+			      struct sk_buff *skb)
+{
+}
+#endif
+
+static void rmnet_map_v5_checksum_uplink_packet(struct sk_buff *skb,
+						struct rmnet_port *port,
+						struct net_device *orig_dev)
+{
+	struct rmnet_priv *priv = netdev_priv(orig_dev);
+	struct rmnet_map_v5_csum_header *ul_header;
+
+	ul_header = skb_push(skb, sizeof(*ul_header));
+	memset(ul_header, 0, sizeof(*ul_header));
+	ul_header->header_info = u8_encode_bits(RMNET_MAP_HEADER_TYPE_CSUM_OFFLOAD,
+						MAPV5_HDRINFO_HDR_TYPE_FMASK);
+
+	if (skb->ip_summed == CHECKSUM_PARTIAL) {
+		void *iph = ip_hdr(skb);
+		__sum16 *check;
+		void *trans;
+		u8 proto;
+
+		if (skb->protocol == htons(ETH_P_IP)) {
+			u16 ip_len = ((struct iphdr *)iph)->ihl * 4;
+
+			proto = ((struct iphdr *)iph)->protocol;
+			trans = iph + ip_len;
+		} else if (IS_ENABLED(CONFIG_IPV6) &&
+			   skb->protocol == htons(ETH_P_IPV6)) {
+			u16 ip_len = sizeof(struct ipv6hdr);
+
+			proto = ((struct ipv6hdr *)iph)->nexthdr;
+			trans = iph + ip_len;
+		} else {
+			priv->stats.csum_err_invalid_ip_version++;
+			goto sw_csum;
+		}
+
+		check = rmnet_map_get_csum_field(proto, trans);
+		if (check) {
+			skb->ip_summed = CHECKSUM_NONE;
+			/* Ask for checksum offloading */
+			ul_header->csum_info |= MAPV5_CSUMINFO_VALID_FLAG;
+			priv->stats.csum_hw++;
+			return;
+		}
+	}
+
+sw_csum:
+	priv->stats.csum_sw++;
+}
+
+/* Adds MAP header to front of skb->data
+ * Padding is calculated and set appropriately in MAP header. Mux ID is
+ * initialized to 0.
+ */
+struct rmnet_map_header *rmnet_map_add_map_header(struct sk_buff *skb,
+						  int hdrlen,
+						  struct rmnet_port *port,
+						  int pad)
+{
+	struct rmnet_map_header *map_header;
+	u32 padding, map_datalen;
+
+	map_datalen = skb->len - hdrlen;
+	map_header = (struct rmnet_map_header *)
+			skb_push(skb, sizeof(struct rmnet_map_header));
+	memset(map_header, 0, sizeof(struct rmnet_map_header));
+
+	/* Set next_hdr bit for csum offload packets */
+	if (port->data_format & RMNET_FLAGS_EGRESS_MAP_CKSUMV5)
+		map_header->flags |= MAP_NEXT_HEADER_FLAG;
+
+	if (pad == RMNET_MAP_NO_PAD_BYTES) {
+		map_header->pkt_len = htons(map_datalen);
+		return map_header;
+	}
+
+	BUILD_BUG_ON(MAP_PAD_LEN_MASK < 3);
+	padding = ALIGN(map_datalen, 4) - map_datalen;
+
+	if (padding == 0)
+		goto done;
+
+	if (skb_tailroom(skb) < padding)
+		return NULL;
+
+	skb_put_zero(skb, padding);
+
+done:
+	map_header->pkt_len = htons(map_datalen + padding);
+	/* This is a data packet, so the CMD bit is 0 */
+	map_header->flags = padding & MAP_PAD_LEN_MASK;
+
+	return map_header;
+}
+
+/* Deaggregates a single packet
+ * A whole new buffer is allocated for each portion of an aggregated frame.
+ * Caller should keep calling deaggregate() on the source skb until 0 is
+ * returned, indicating that there are no more packets to deaggregate. Caller
+ * is responsible for freeing the original skb.
+ */
+struct sk_buff *rmnet_map_deaggregate(struct sk_buff *skb,
+				      struct rmnet_port *port)
+{
+	struct rmnet_map_v5_csum_header *next_hdr = NULL;
+	struct rmnet_map_header *maph;
+	void *data = skb->data;
+	struct sk_buff *skbn;
+	u8 nexthdr_type;
+	u32 packet_len;
+
+	if (skb->len == 0)
+		return NULL;
+
+	maph = (struct rmnet_map_header *)skb->data;
+	packet_len = ntohs(maph->pkt_len) + sizeof(*maph);
+
+	if (port->data_format & RMNET_FLAGS_INGRESS_MAP_CKSUMV4) {
+		packet_len += sizeof(struct rmnet_map_dl_csum_trailer);
+	} else if (port->data_format & RMNET_FLAGS_INGRESS_MAP_CKSUMV5) {
+		if (!(maph->flags & MAP_CMD_FLAG)) {
+			packet_len += sizeof(*next_hdr);
+			if (maph->flags & MAP_NEXT_HEADER_FLAG)
+				next_hdr = data + sizeof(*maph);
+			else
+				/* Mapv5 data pkt without csum hdr is invalid */
+				return NULL;
+		}
+	}
+
+	if (((int)skb->len - (int)packet_len) < 0)
+		return NULL;
+
+	/* Some hardware can send us empty frames. Catch them */
+	if (!maph->pkt_len)
+		return NULL;
+
+	if (next_hdr) {
+		nexthdr_type = u8_get_bits(next_hdr->header_info,
+					   MAPV5_HDRINFO_HDR_TYPE_FMASK);
+		if (nexthdr_type != RMNET_MAP_HEADER_TYPE_CSUM_OFFLOAD)
+			return NULL;
+	}
+
+	skbn = alloc_skb(packet_len + RMNET_MAP_DEAGGR_SPACING, GFP_ATOMIC);
+	if (!skbn)
+		return NULL;
+
+	skb_reserve(skbn, RMNET_MAP_DEAGGR_HEADROOM);
+	skb_put(skbn, packet_len);
+	memcpy(skbn->data, skb->data, packet_len);
+	skb_pull(skb, packet_len);
+
+	return skbn;
+}
+
+/* Validates packet checksums. Function takes a pointer to
+ * the beginning of a buffer which contains the IP payload +
+ * padding + checksum trailer.
+ * Only IPv4 and IPv6 are supported along with TCP & UDP.
+ * Fragmented or tunneled packets are not supported.
+ */
+int rmnet_map_checksum_downlink_packet(struct sk_buff *skb, u16 len)
+{
+	struct rmnet_priv *priv = netdev_priv(skb->dev);
+	struct rmnet_map_dl_csum_trailer *csum_trailer;
+
+	if (unlikely(!(skb->dev->features & NETIF_F_RXCSUM))) {
+		priv->stats.csum_sw++;
+		return -EOPNOTSUPP;
+	}
+
+	csum_trailer = (struct rmnet_map_dl_csum_trailer *)(skb->data + len);
+
+	if (!(csum_trailer->flags & MAP_CSUM_DL_VALID_FLAG)) {
+		priv->stats.csum_valid_unset++;
+		return -EINVAL;
+	}
+
+	if (skb->protocol == htons(ETH_P_IP))
+		return rmnet_map_ipv4_dl_csum_trailer(skb, csum_trailer, priv);
+
+	if (IS_ENABLED(CONFIG_IPV6) && skb->protocol == htons(ETH_P_IPV6))
+		return rmnet_map_ipv6_dl_csum_trailer(skb, csum_trailer, priv);
+
+	priv->stats.csum_err_invalid_ip_version++;
+
+	return -EPROTONOSUPPORT;
+}
+
+static void rmnet_map_v4_checksum_uplink_packet(struct sk_buff *skb,
+						struct net_device *orig_dev)
+{
+	struct rmnet_priv *priv = netdev_priv(orig_dev);
+	struct rmnet_map_ul_csum_header *ul_header;
+	void *iphdr;
+
+	ul_header = (struct rmnet_map_ul_csum_header *)
+		    skb_push(skb, sizeof(struct rmnet_map_ul_csum_header));
+
+	if (unlikely(!(orig_dev->features &
+		     (NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM))))
+		goto sw_csum;
+
+	if (skb->ip_summed != CHECKSUM_PARTIAL)
+		goto sw_csum;
+
+	iphdr = (char *)ul_header +
+		sizeof(struct rmnet_map_ul_csum_header);
+
+	if (skb->protocol == htons(ETH_P_IP)) {
+		rmnet_map_ipv4_ul_csum_header(iphdr, ul_header, skb);
+		priv->stats.csum_hw++;
+		return;
+	}
+
+	if (IS_ENABLED(CONFIG_IPV6) && skb->protocol == htons(ETH_P_IPV6)) {
+		rmnet_map_ipv6_ul_csum_header(iphdr, ul_header, skb);
+		priv->stats.csum_hw++;
+		return;
+	}
+
+	priv->stats.csum_err_invalid_ip_version++;
+
+sw_csum:
+	memset(ul_header, 0, sizeof(*ul_header));
+
+	priv->stats.csum_sw++;
+}
+
+/* Generates UL checksum meta info header for IPv4 and IPv6 over TCP and UDP
+ * packets that are supported for UL checksum offload.
+ */
+void rmnet_map_checksum_uplink_packet(struct sk_buff *skb,
+				      struct rmnet_port *port,
+				      struct net_device *orig_dev,
+				      int csum_type)
+{
+	switch (csum_type) {
+	case RMNET_FLAGS_EGRESS_MAP_CKSUMV4:
+		rmnet_map_v4_checksum_uplink_packet(skb, orig_dev);
+		break;
+	case RMNET_FLAGS_EGRESS_MAP_CKSUMV5:
+		rmnet_map_v5_checksum_uplink_packet(skb, port, orig_dev);
+		break;
+	default:
+		break;
+	}
+}
+
+/* Process a MAPv5 packet header */
+int rmnet_map_process_next_hdr_packet(struct sk_buff *skb,
+				      u16 len)
+{
+	struct rmnet_priv *priv = netdev_priv(skb->dev);
+	struct rmnet_map_v5_csum_header *next_hdr;
+	u8 nexthdr_type;
+
+	next_hdr = (struct rmnet_map_v5_csum_header *)(skb->data +
+			sizeof(struct rmnet_map_header));
+
+	nexthdr_type = u8_get_bits(next_hdr->header_info,
+				   MAPV5_HDRINFO_HDR_TYPE_FMASK);
+
+	if (nexthdr_type != RMNET_MAP_HEADER_TYPE_CSUM_OFFLOAD)
+		return -EINVAL;
+
+	if (unlikely(!(skb->dev->features & NETIF_F_RXCSUM))) {
+		priv->stats.csum_sw++;
+	} else if (next_hdr->csum_info & MAPV5_CSUMINFO_VALID_FLAG) {
+		priv->stats.csum_ok++;
+		skb->ip_summed = CHECKSUM_UNNECESSARY;
+	} else {
+		priv->stats.csum_valid_unset++;
+	}
+
+	/* Pull csum v5 header */
+	skb_pull(skb, sizeof(*next_hdr));
+
+	return 0;
+}
diff --git a/drivers/net/ethernet/qualcomm/rmnet/rmnet_private.h b/drivers/net/ethernet/qualcomm/rmnet/rmnet_private.h
new file mode 100644
index 000000000..e1337f164
--- /dev/null
+++ b/drivers/net/ethernet/qualcomm/rmnet/rmnet_private.h
@@ -0,0 +1,18 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/* Copyright (c) 2013-2014, 2016-2018 The Linux Foundation. All rights reserved.
+ */
+
+#ifndef _RMNET_PRIVATE_H_
+#define _RMNET_PRIVATE_H_
+
+#define RMNET_MAX_PACKET_SIZE      16384
+#define RMNET_DFLT_PACKET_SIZE     1500
+#define RMNET_NEEDED_HEADROOM      16
+#define RMNET_TX_QUEUE_LEN         1000
+
+/* Replace skb->dev to a virtual rmnet device and pass up the stack */
+#define RMNET_EPMODE_VND (1)
+/* Pass the frame directly to another device with dev_queue_xmit() */
+#define RMNET_EPMODE_BRIDGE (2)
+
+#endif /* _RMNET_PRIVATE_H_ */
diff --git a/drivers/net/ethernet/qualcomm/rmnet/rmnet_vnd.c b/drivers/net/ethernet/qualcomm/rmnet/rmnet_vnd.c
new file mode 100644
index 000000000..1b2119b1d
--- /dev/null
+++ b/drivers/net/ethernet/qualcomm/rmnet/rmnet_vnd.c
@@ -0,0 +1,359 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* Copyright (c) 2013-2018, The Linux Foundation. All rights reserved.
+ *
+ * RMNET Data virtual network driver
+ */
+
+#include <linux/etherdevice.h>
+#include <linux/ethtool.h>
+#include <linux/if_arp.h>
+#include <net/pkt_sched.h>
+#include "rmnet_config.h"
+#include "rmnet_handlers.h"
+#include "rmnet_private.h"
+#include "rmnet_map.h"
+#include "rmnet_vnd.h"
+
+/* RX/TX Fixup */
+
+void rmnet_vnd_rx_fixup(struct sk_buff *skb, struct net_device *dev)
+{
+	struct rmnet_priv *priv = netdev_priv(dev);
+	struct rmnet_pcpu_stats *pcpu_ptr;
+
+	pcpu_ptr = this_cpu_ptr(priv->pcpu_stats);
+
+	u64_stats_update_begin(&pcpu_ptr->syncp);
+	pcpu_ptr->stats.rx_pkts++;
+	pcpu_ptr->stats.rx_bytes += skb->len;
+	u64_stats_update_end(&pcpu_ptr->syncp);
+}
+
+void rmnet_vnd_tx_fixup(struct sk_buff *skb, struct net_device *dev)
+{
+	struct rmnet_priv *priv = netdev_priv(dev);
+	struct rmnet_pcpu_stats *pcpu_ptr;
+
+	pcpu_ptr = this_cpu_ptr(priv->pcpu_stats);
+
+	u64_stats_update_begin(&pcpu_ptr->syncp);
+	pcpu_ptr->stats.tx_pkts++;
+	pcpu_ptr->stats.tx_bytes += skb->len;
+	u64_stats_update_end(&pcpu_ptr->syncp);
+}
+
+/* Network Device Operations */
+
+static netdev_tx_t rmnet_vnd_start_xmit(struct sk_buff *skb,
+					struct net_device *dev)
+{
+	struct rmnet_priv *priv;
+
+	priv = netdev_priv(dev);
+	if (priv->real_dev) {
+		rmnet_egress_handler(skb);
+	} else {
+		this_cpu_inc(priv->pcpu_stats->stats.tx_drops);
+		kfree_skb(skb);
+	}
+	return NETDEV_TX_OK;
+}
+
+static int rmnet_vnd_headroom(struct rmnet_port *port)
+{
+	u32 headroom;
+
+	headroom = sizeof(struct rmnet_map_header);
+
+	if (port->data_format & RMNET_FLAGS_EGRESS_MAP_CKSUMV4)
+		headroom += sizeof(struct rmnet_map_ul_csum_header);
+
+	return headroom;
+}
+
+static int rmnet_vnd_change_mtu(struct net_device *rmnet_dev, int new_mtu)
+{
+	struct rmnet_priv *priv = netdev_priv(rmnet_dev);
+	struct rmnet_port *port;
+	u32 headroom;
+
+	port = rmnet_get_port_rtnl(priv->real_dev);
+
+	headroom = rmnet_vnd_headroom(port);
+
+	if (new_mtu < 0 || new_mtu > RMNET_MAX_PACKET_SIZE ||
+	    new_mtu > (priv->real_dev->mtu - headroom))
+		return -EINVAL;
+
+	rmnet_dev->mtu = new_mtu;
+	return 0;
+}
+
+static int rmnet_vnd_get_iflink(const struct net_device *dev)
+{
+	struct rmnet_priv *priv = netdev_priv(dev);
+
+	return priv->real_dev->ifindex;
+}
+
+static int rmnet_vnd_init(struct net_device *dev)
+{
+	struct rmnet_priv *priv = netdev_priv(dev);
+	int err;
+
+	priv->pcpu_stats = alloc_percpu(struct rmnet_pcpu_stats);
+	if (!priv->pcpu_stats)
+		return -ENOMEM;
+
+	err = gro_cells_init(&priv->gro_cells, dev);
+	if (err) {
+		free_percpu(priv->pcpu_stats);
+		return err;
+	}
+
+	return 0;
+}
+
+static void rmnet_vnd_uninit(struct net_device *dev)
+{
+	struct rmnet_priv *priv = netdev_priv(dev);
+
+	gro_cells_destroy(&priv->gro_cells);
+	free_percpu(priv->pcpu_stats);
+}
+
+static void rmnet_get_stats64(struct net_device *dev,
+			      struct rtnl_link_stats64 *s)
+{
+	struct rmnet_priv *priv = netdev_priv(dev);
+	struct rmnet_vnd_stats total_stats = { };
+	struct rmnet_pcpu_stats *pcpu_ptr;
+	struct rmnet_vnd_stats snapshot;
+	unsigned int cpu, start;
+
+	for_each_possible_cpu(cpu) {
+		pcpu_ptr = per_cpu_ptr(priv->pcpu_stats, cpu);
+
+		do {
+			start = u64_stats_fetch_begin_irq(&pcpu_ptr->syncp);
+			snapshot = pcpu_ptr->stats;	/* struct assignment */
+		} while (u64_stats_fetch_retry_irq(&pcpu_ptr->syncp, start));
+
+		total_stats.rx_pkts += snapshot.rx_pkts;
+		total_stats.rx_bytes += snapshot.rx_bytes;
+		total_stats.tx_pkts += snapshot.tx_pkts;
+		total_stats.tx_bytes += snapshot.tx_bytes;
+		total_stats.tx_drops += snapshot.tx_drops;
+	}
+
+	s->rx_packets = total_stats.rx_pkts;
+	s->rx_bytes = total_stats.rx_bytes;
+	s->tx_packets = total_stats.tx_pkts;
+	s->tx_bytes = total_stats.tx_bytes;
+	s->tx_dropped = total_stats.tx_drops;
+}
+
+static const struct net_device_ops rmnet_vnd_ops = {
+	.ndo_start_xmit = rmnet_vnd_start_xmit,
+	.ndo_change_mtu = rmnet_vnd_change_mtu,
+	.ndo_get_iflink = rmnet_vnd_get_iflink,
+	.ndo_add_slave  = rmnet_add_bridge,
+	.ndo_del_slave  = rmnet_del_bridge,
+	.ndo_init       = rmnet_vnd_init,
+	.ndo_uninit     = rmnet_vnd_uninit,
+	.ndo_get_stats64 = rmnet_get_stats64,
+};
+
+static const char rmnet_gstrings_stats[][ETH_GSTRING_LEN] = {
+	"Checksum ok",
+	"Bad IPv4 header checksum",
+	"Checksum valid bit not set",
+	"Checksum validation failed",
+	"Checksum error bad buffer",
+	"Checksum error bad ip version",
+	"Checksum error bad transport",
+	"Checksum skipped on ip fragment",
+	"Checksum skipped",
+	"Checksum computed in software",
+	"Checksum computed in hardware",
+};
+
+static void rmnet_get_strings(struct net_device *dev, u32 stringset, u8 *buf)
+{
+	switch (stringset) {
+	case ETH_SS_STATS:
+		memcpy(buf, &rmnet_gstrings_stats,
+		       sizeof(rmnet_gstrings_stats));
+		break;
+	}
+}
+
+static int rmnet_get_sset_count(struct net_device *dev, int sset)
+{
+	switch (sset) {
+	case ETH_SS_STATS:
+		return ARRAY_SIZE(rmnet_gstrings_stats);
+	default:
+		return -EOPNOTSUPP;
+	}
+}
+
+static void rmnet_get_ethtool_stats(struct net_device *dev,
+				    struct ethtool_stats *stats, u64 *data)
+{
+	struct rmnet_priv *priv = netdev_priv(dev);
+	struct rmnet_priv_stats *st = &priv->stats;
+
+	if (!data)
+		return;
+
+	memcpy(data, st, ARRAY_SIZE(rmnet_gstrings_stats) * sizeof(u64));
+}
+
+static const struct ethtool_ops rmnet_ethtool_ops = {
+	.get_ethtool_stats = rmnet_get_ethtool_stats,
+	.get_strings = rmnet_get_strings,
+	.get_sset_count = rmnet_get_sset_count,
+};
+
+/* Called by kernel whenever a new rmnet<n> device is created. Sets MTU,
+ * flags, ARP type, needed headroom, etc...
+ */
+void rmnet_vnd_setup(struct net_device *rmnet_dev)
+{
+	rmnet_dev->netdev_ops = &rmnet_vnd_ops;
+	rmnet_dev->mtu = RMNET_DFLT_PACKET_SIZE;
+	rmnet_dev->needed_headroom = RMNET_NEEDED_HEADROOM;
+	eth_hw_addr_random(rmnet_dev);
+	rmnet_dev->tx_queue_len = RMNET_TX_QUEUE_LEN;
+
+	/* Raw IP mode */
+	rmnet_dev->header_ops = NULL;  /* No header */
+	rmnet_dev->type = ARPHRD_RAWIP;
+	rmnet_dev->hard_header_len = 0;
+	rmnet_dev->flags &= ~(IFF_BROADCAST | IFF_MULTICAST);
+
+	rmnet_dev->needs_free_netdev = true;
+	rmnet_dev->ethtool_ops = &rmnet_ethtool_ops;
+
+	rmnet_dev->features |= NETIF_F_LLTX;
+
+	/* This perm addr will be used as interface identifier by IPv6 */
+	rmnet_dev->addr_assign_type = NET_ADDR_RANDOM;
+	eth_random_addr(rmnet_dev->perm_addr);
+}
+
+/* Exposed API */
+
+int rmnet_vnd_newlink(u8 id, struct net_device *rmnet_dev,
+		      struct rmnet_port *port,
+		      struct net_device *real_dev,
+		      struct rmnet_endpoint *ep,
+		      struct netlink_ext_ack *extack)
+
+{
+	struct rmnet_priv *priv = netdev_priv(rmnet_dev);
+	u32 headroom;
+	int rc;
+
+	if (rmnet_get_endpoint(port, id)) {
+		NL_SET_ERR_MSG_MOD(extack, "MUX ID already exists");
+		return -EBUSY;
+	}
+
+	rmnet_dev->hw_features = NETIF_F_RXCSUM;
+	rmnet_dev->hw_features |= NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM;
+	rmnet_dev->hw_features |= NETIF_F_SG;
+
+	priv->real_dev = real_dev;
+
+	headroom = rmnet_vnd_headroom(port);
+
+	if (rmnet_vnd_change_mtu(rmnet_dev, real_dev->mtu - headroom)) {
+		NL_SET_ERR_MSG_MOD(extack, "Invalid MTU on real dev");
+		return -EINVAL;
+	}
+
+	rc = register_netdevice(rmnet_dev);
+	if (!rc) {
+		ep->egress_dev = rmnet_dev;
+		ep->mux_id = id;
+		port->nr_rmnet_devs++;
+
+		rmnet_dev->rtnl_link_ops = &rmnet_link_ops;
+
+		priv->mux_id = id;
+
+		netdev_dbg(rmnet_dev, "rmnet dev created\n");
+	}
+
+	return rc;
+}
+
+int rmnet_vnd_dellink(u8 id, struct rmnet_port *port,
+		      struct rmnet_endpoint *ep)
+{
+	if (id >= RMNET_MAX_LOGICAL_EP || !ep->egress_dev)
+		return -EINVAL;
+
+	ep->egress_dev = NULL;
+	port->nr_rmnet_devs--;
+	return 0;
+}
+
+int rmnet_vnd_do_flow_control(struct net_device *rmnet_dev, int enable)
+{
+	netdev_dbg(rmnet_dev, "Setting VND TX queue state to %d\n", enable);
+	/* Although we expect similar number of enable/disable
+	 * commands, optimize for the disable. That is more
+	 * latency sensitive than enable
+	 */
+	if (unlikely(enable))
+		netif_wake_queue(rmnet_dev);
+	else
+		netif_stop_queue(rmnet_dev);
+
+	return 0;
+}
+
+int rmnet_vnd_validate_real_dev_mtu(struct net_device *real_dev)
+{
+	struct hlist_node *tmp_ep;
+	struct rmnet_endpoint *ep;
+	struct rmnet_port *port;
+	unsigned long bkt_ep;
+	u32 headroom;
+
+	port = rmnet_get_port_rtnl(real_dev);
+
+	headroom = rmnet_vnd_headroom(port);
+
+	hash_for_each_safe(port->muxed_ep, bkt_ep, tmp_ep, ep, hlnode) {
+		if (ep->egress_dev->mtu > (real_dev->mtu - headroom))
+			return -1;
+	}
+
+	return 0;
+}
+
+int rmnet_vnd_update_dev_mtu(struct rmnet_port *port,
+			     struct net_device *real_dev)
+{
+	struct hlist_node *tmp_ep;
+	struct rmnet_endpoint *ep;
+	unsigned long bkt_ep;
+	u32 headroom;
+
+	headroom = rmnet_vnd_headroom(port);
+
+	hash_for_each_safe(port->muxed_ep, bkt_ep, tmp_ep, ep, hlnode) {
+		if (ep->egress_dev->mtu <= (real_dev->mtu - headroom))
+			continue;
+
+		if (rmnet_vnd_change_mtu(ep->egress_dev,
+					 real_dev->mtu - headroom))
+			return -1;
+	}
+
+	return 0;
+}
diff --git a/drivers/net/ethernet/qualcomm/rmnet/rmnet_vnd.h b/drivers/net/ethernet/qualcomm/rmnet/rmnet_vnd.h
new file mode 100644
index 000000000..dc3a4443e
--- /dev/null
+++ b/drivers/net/ethernet/qualcomm/rmnet/rmnet_vnd.h
@@ -0,0 +1,24 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/* Copyright (c) 2013-2017, The Linux Foundation. All rights reserved.
+ *
+ * RMNET Data Virtual Network Device APIs
+ */
+
+#ifndef _RMNET_VND_H_
+#define _RMNET_VND_H_
+
+int rmnet_vnd_do_flow_control(struct net_device *dev, int enable);
+int rmnet_vnd_newlink(u8 id, struct net_device *rmnet_dev,
+		      struct rmnet_port *port,
+		      struct net_device *real_dev,
+		      struct rmnet_endpoint *ep,
+		      struct netlink_ext_ack *extack);
+int rmnet_vnd_dellink(u8 id, struct rmnet_port *port,
+		      struct rmnet_endpoint *ep);
+void rmnet_vnd_rx_fixup(struct sk_buff *skb, struct net_device *dev);
+void rmnet_vnd_tx_fixup(struct sk_buff *skb, struct net_device *dev);
+void rmnet_vnd_setup(struct net_device *dev);
+int rmnet_vnd_validate_real_dev_mtu(struct net_device *real_dev);
+int rmnet_vnd_update_dev_mtu(struct rmnet_port *port,
+			     struct net_device *real_dev);
+#endif /* _RMNET_VND_H_ */