--- /dev/null
+1. Introduction
+
+rmnet driver is used for supporting the Multiplexing and aggregation
+Protocol (MAP). This protocol is used by all recent chipsets using Qualcomm
+Technologies, Inc. modems.
+
+This driver can be used to register onto any physical network device in
+IP mode. Physical transports include USB, HSIC, PCIe and IP accelerator.
+
+Multiplexing allows for creation of logical netdevices (rmnet devices) to
+handle multiple private data networks (PDN) like a default internet, tethering,
+multimedia messaging service (MMS) or IP media subsystem (IMS). Hardware sends
+packets with MAP headers to rmnet. Based on the multiplexer id, rmnet
+routes to the appropriate PDN after removing the MAP header.
+
+Aggregation is required to achieve high data rates. This involves hardware
+sending aggregated bunch of MAP frames. rmnet driver will de-aggregate
+these MAP frames and send them to appropriate PDN's.
+
+2. Packet format
+
+a. MAP packet (data / control)
+
+MAP header has the same endianness of the IP packet.
+
+Packet format -
+
+Bit 0 1 2-7 8 - 15 16 - 31
+Function Command / Data Reserved Pad Multiplexer ID Payload length
+Bit 32 - x
+Function Raw Bytes
+
+Command (1)/ Data (0) bit value is to indicate if the packet is a MAP command
+or data packet. Control packet is used for transport level flow control. Data
+packets are standard IP packets.
+
+Reserved bits are usually zeroed out and to be ignored by receiver.
+
+Padding is number of bytes to be added for 4 byte alignment if required by
+hardware.
+
+Multiplexer ID is to indicate the PDN on which data has to be sent.
+
+Payload length includes the padding length but does not include MAP header
+length.
+
+b. MAP packet (command specific)
+
+Bit 0 1 2-7 8 - 15 16 - 31
+Function Command Reserved Pad Multiplexer ID Payload length
+Bit 32 - 39 40 - 45 46 - 47 48 - 63
+Function Command name Reserved Command Type Reserved
+Bit 64 - 95
+Function Transaction ID
+Bit 96 - 127
+Function Command data
+
+Command 1 indicates disabling flow while 2 is enabling flow
+
+Command types -
+0 for MAP command request
+1 is to acknowledge the receipt of a command
+2 is for unsupported commands
+3 is for error during processing of commands
+
+c. Aggregation
+
+Aggregation is multiple MAP packets (can be data or command) delivered to
+rmnet in a single linear skb. rmnet will process the individual
+packets and either ACK the MAP command or deliver the IP packet to the
+network stack as needed
+
+MAP header|IP Packet|Optional padding|MAP header|IP Packet|Optional padding....
+MAP header|IP Packet|Optional padding|MAP header|Command Packet|Optional pad...
+
+3. Userspace configuration
+
+rmnet userspace configuration is done through netlink library librmnetctl
+and command line utility rmnetcli. Utility is hosted in codeaurora forum git.
+The driver uses rtnl_link_ops for communication.
+
+https://source.codeaurora.org/quic/la/platform/vendor/qcom-opensource/dataservices/tree/rmnetctl
low power, Receive-Side Scaling (RSS), and IEEE 1588-2008
Precision Clock Synchronization Protocol.
+source "drivers/net/ethernet/qualcomm/rmnet/Kconfig"
+
endif # NET_VENDOR_QUALCOMM
qcauart-objs := qca_uart.o
obj-y += emac/
+
+obj-$(CONFIG_RMNET) += rmnet/
--- /dev/null
+#
+# RMNET MAP driver
+#
+
+menuconfig RMNET
+ tristate "RmNet MAP driver"
+ default n
+ ---help---
+ If you select this, you will enable the RMNET module which is used
+ for handling data in the multiplexing and aggregation protocol (MAP)
+ format in the embedded data path. RMNET devices can be attached to
+ any IP mode physical device.
--- /dev/null
+#
+# Makefile for the RMNET module
+#
+
+rmnet-y := rmnet_config.o
+rmnet-y += rmnet_vnd.o
+rmnet-y += rmnet_handlers.o
+rmnet-y += rmnet_map_data.o
+rmnet-y += rmnet_map_command.o
+obj-$(CONFIG_RMNET) += rmnet.o
--- /dev/null
+/* Copyright (c) 2013-2017, The Linux Foundation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * 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"
+
+/* Locking scheme -
+ * The shared resource which needs to be protected is realdev->rx_handler_data.
+ * For the writer path, this is using rtnl_lock(). The writer paths are
+ * rmnet_newlink(), rmnet_dellink() and rmnet_force_unassociate_device(). These
+ * paths are already called with rtnl_lock() acquired in. There is also an
+ * ASSERT_RTNL() to ensure that we are calling with rtnl acquired. For
+ * dereference here, we will need to use rtnl_dereference(). Dev list writing
+ * needs to happen with rtnl_lock() acquired for netdev_master_upper_dev_link().
+ * For the reader path, the real_dev->rx_handler_data is called in the TX / RX
+ * path. We only need rcu_read_lock() for these scenarios. In these cases,
+ * the rcu_read_lock() is held in __dev_queue_xmit() and
+ * netif_receive_skb_internal(), so readers need to use rcu_dereference_rtnl()
+ * to get the relevant information. For dev list reading, we again acquire
+ * rcu_read_lock() in rmnet_dellink() for netdev_master_upper_dev_get_rcu().
+ * We also use unregister_netdevice_many() to free all rmnet devices in
+ * rmnet_force_unassociate_device() so we dont lose the rtnl_lock() and free in
+ * same context.
+ */
+
+/* Local Definitions and Declarations */
+#define RMNET_LOCAL_LOGICAL_ENDPOINT -1
+
+struct rmnet_walk_data {
+ struct net_device *real_dev;
+ struct list_head *head;
+ struct rmnet_real_dev_info *real_dev_info;
+};
+
+static int rmnet_is_real_dev_registered(const struct net_device *real_dev)
+{
+ rx_handler_func_t *rx_handler;
+
+ rx_handler = rcu_dereference(real_dev->rx_handler);
+ return (rx_handler == rmnet_rx_handler);
+}
+
+/* Needs either rcu_read_lock() or rtnl lock */
+static struct rmnet_real_dev_info*
+__rmnet_get_real_dev_info(const struct net_device *real_dev)
+{
+ if (rmnet_is_real_dev_registered(real_dev))
+ return rcu_dereference_rtnl(real_dev->rx_handler_data);
+ else
+ return NULL;
+}
+
+/* Needs rtnl lock */
+static struct rmnet_real_dev_info*
+rmnet_get_real_dev_info_rtnl(const struct net_device *real_dev)
+{
+ return rtnl_dereference(real_dev->rx_handler_data);
+}
+
+static struct rmnet_endpoint*
+rmnet_get_endpoint(struct net_device *dev, int config_id)
+{
+ struct rmnet_real_dev_info *r;
+ struct rmnet_endpoint *ep;
+
+ if (!rmnet_is_real_dev_registered(dev)) {
+ ep = rmnet_vnd_get_endpoint(dev);
+ } else {
+ r = __rmnet_get_real_dev_info(dev);
+
+ if (!r)
+ return NULL;
+
+ if (config_id == RMNET_LOCAL_LOGICAL_ENDPOINT)
+ ep = &r->local_ep;
+ else
+ ep = &r->muxed_ep[config_id];
+ }
+
+ return ep;
+}
+
+static int rmnet_unregister_real_device(struct net_device *real_dev,
+ struct rmnet_real_dev_info *r)
+{
+ if (r->nr_rmnet_devs)
+ return -EINVAL;
+
+ kfree(r);
+
+ netdev_rx_handler_unregister(real_dev);
+
+ /* release reference on real_dev */
+ dev_put(real_dev);
+
+ netdev_dbg(real_dev, "Removed from rmnet\n");
+ return 0;
+}
+
+static int rmnet_register_real_device(struct net_device *real_dev)
+{
+ struct rmnet_real_dev_info *r;
+ int rc;
+
+ ASSERT_RTNL();
+
+ if (rmnet_is_real_dev_registered(real_dev))
+ return 0;
+
+ r = kzalloc(sizeof(*r), GFP_ATOMIC);
+ if (!r)
+ return -ENOMEM;
+
+ r->dev = real_dev;
+ rc = netdev_rx_handler_register(real_dev, rmnet_rx_handler, r);
+ if (rc) {
+ kfree(r);
+ return -EBUSY;
+ }
+
+ /* hold on to real dev for MAP data */
+ dev_hold(real_dev);
+
+ netdev_dbg(real_dev, "registered with rmnet\n");
+ return 0;
+}
+
+static int rmnet_set_ingress_data_format(struct net_device *dev, u32 idf)
+{
+ struct rmnet_real_dev_info *r;
+
+ netdev_dbg(dev, "Ingress format 0x%08X\n", idf);
+
+ r = __rmnet_get_real_dev_info(dev);
+
+ r->ingress_data_format = idf;
+
+ return 0;
+}
+
+static int rmnet_set_egress_data_format(struct net_device *dev, u32 edf,
+ u16 agg_size, u16 agg_count)
+{
+ struct rmnet_real_dev_info *r;
+
+ netdev_dbg(dev, "Egress format 0x%08X agg size %d cnt %d\n",
+ edf, agg_size, agg_count);
+
+ r = __rmnet_get_real_dev_info(dev);
+
+ r->egress_data_format = edf;
+
+ return 0;
+}
+
+static int __rmnet_set_endpoint_config(struct net_device *dev, int config_id,
+ struct rmnet_endpoint *ep)
+{
+ struct rmnet_endpoint *dev_ep;
+
+ dev_ep = rmnet_get_endpoint(dev, config_id);
+
+ if (!dev_ep)
+ return -EINVAL;
+
+ memcpy(dev_ep, ep, sizeof(struct rmnet_endpoint));
+ if (config_id == RMNET_LOCAL_LOGICAL_ENDPOINT)
+ dev_ep->mux_id = 0;
+ else
+ dev_ep->mux_id = config_id;
+
+ return 0;
+}
+
+static int rmnet_set_endpoint_config(struct net_device *dev,
+ int config_id, u8 rmnet_mode,
+ struct net_device *egress_dev)
+{
+ struct rmnet_endpoint ep;
+
+ netdev_dbg(dev, "id %d mode %d dev %s\n",
+ config_id, rmnet_mode, egress_dev->name);
+
+ if (config_id < RMNET_LOCAL_LOGICAL_ENDPOINT ||
+ config_id >= RMNET_MAX_LOGICAL_EP)
+ return -EINVAL;
+
+ /* This config is cleared on every set, so its ok to not
+ * clear it on a device delete.
+ */
+ memset(&ep, 0, sizeof(struct rmnet_endpoint));
+ ep.rmnet_mode = rmnet_mode;
+ ep.egress_dev = egress_dev;
+
+ return __rmnet_set_endpoint_config(dev, config_id, &ep);
+}
+
+static int rmnet_newlink(struct net *src_net, struct net_device *dev,
+ struct nlattr *tb[], struct nlattr *data[],
+ struct netlink_ext_ack *extack)
+{
+ int ingress_format = RMNET_INGRESS_FORMAT_DEMUXING |
+ RMNET_INGRESS_FORMAT_DEAGGREGATION |
+ RMNET_INGRESS_FORMAT_MAP;
+ int egress_format = RMNET_EGRESS_FORMAT_MUXING |
+ RMNET_EGRESS_FORMAT_MAP;
+ struct rmnet_real_dev_info *r;
+ struct net_device *real_dev;
+ int mode = RMNET_EPMODE_VND;
+ int err = 0;
+ u16 mux_id;
+
+ real_dev = __dev_get_by_index(src_net, nla_get_u32(tb[IFLA_LINK]));
+ if (!real_dev || !dev)
+ return -ENODEV;
+
+ if (!data[IFLA_VLAN_ID])
+ return -EINVAL;
+
+ mux_id = nla_get_u16(data[IFLA_VLAN_ID]);
+
+ err = rmnet_register_real_device(real_dev);
+ if (err)
+ goto err0;
+
+ r = rmnet_get_real_dev_info_rtnl(real_dev);
+ err = rmnet_vnd_newlink(mux_id, dev, r);
+ if (err)
+ goto err1;
+
+ err = netdev_master_upper_dev_link(dev, real_dev, NULL, NULL);
+ if (err)
+ goto err2;
+
+ rmnet_vnd_set_mux(dev, mux_id);
+ rmnet_set_egress_data_format(real_dev, egress_format, 0, 0);
+ rmnet_set_ingress_data_format(real_dev, ingress_format);
+ rmnet_set_endpoint_config(real_dev, mux_id, mode, dev);
+ rmnet_set_endpoint_config(dev, mux_id, mode, real_dev);
+ return 0;
+
+err2:
+ rmnet_vnd_dellink(mux_id, r);
+err1:
+ rmnet_unregister_real_device(real_dev, r);
+err0:
+ return err;
+}
+
+static void rmnet_dellink(struct net_device *dev, struct list_head *head)
+{
+ struct rmnet_real_dev_info *r;
+ struct net_device *real_dev;
+ u8 mux_id;
+
+ rcu_read_lock();
+ real_dev = netdev_master_upper_dev_get_rcu(dev);
+ rcu_read_unlock();
+
+ if (!real_dev || !rmnet_is_real_dev_registered(real_dev))
+ return;
+
+ r = rmnet_get_real_dev_info_rtnl(real_dev);
+
+ mux_id = rmnet_vnd_get_mux(dev);
+ rmnet_vnd_dellink(mux_id, r);
+ netdev_upper_dev_unlink(dev, real_dev);
+ rmnet_unregister_real_device(real_dev, r);
+
+ unregister_netdevice_queue(dev, head);
+}
+
+static int rmnet_dev_walk_unreg(struct net_device *rmnet_dev, void *data)
+{
+ struct rmnet_walk_data *d = data;
+ u8 mux_id;
+
+ mux_id = rmnet_vnd_get_mux(rmnet_dev);
+
+ rmnet_vnd_dellink(mux_id, d->real_dev_info);
+ netdev_upper_dev_unlink(rmnet_dev, d->real_dev);
+ unregister_netdevice_queue(rmnet_dev, d->head);
+
+ return 0;
+}
+
+static void rmnet_force_unassociate_device(struct net_device *dev)
+{
+ struct net_device *real_dev = dev;
+ struct rmnet_real_dev_info *r;
+ struct rmnet_walk_data d;
+ LIST_HEAD(list);
+
+ if (!rmnet_is_real_dev_registered(real_dev))
+ return;
+
+ ASSERT_RTNL();
+
+ d.real_dev = real_dev;
+ d.head = &list;
+
+ r = rmnet_get_real_dev_info_rtnl(dev);
+ d.real_dev_info = r;
+
+ rcu_read_lock();
+ netdev_walk_all_lower_dev_rcu(real_dev, rmnet_dev_walk_unreg, &d);
+ rcu_read_unlock();
+ unregister_netdevice_many(&list);
+
+ rmnet_unregister_real_device(real_dev, r);
+}
+
+static int rmnet_config_notify_cb(struct notifier_block *nb,
+ unsigned long event, void *data)
+{
+ struct net_device *dev = netdev_notifier_info_to_dev(data);
+
+ if (!dev)
+ return NOTIFY_DONE;
+
+ switch (event) {
+ case NETDEV_UNREGISTER:
+ netdev_dbg(dev, "Kernel unregister\n");
+ rmnet_force_unassociate_device(dev);
+ 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_VLAN_ID])
+ return -EINVAL;
+
+ mux_id = nla_get_u16(data[IFLA_VLAN_ID]);
+ if (mux_id > (RMNET_MAX_LOGICAL_EP - 1))
+ return -ERANGE;
+
+ return 0;
+}
+
+static size_t rmnet_get_size(const struct net_device *dev)
+{
+ return nla_total_size(2); /* IFLA_VLAN_ID */
+}
+
+struct rtnl_link_ops rmnet_link_ops __read_mostly = {
+ .kind = "rmnet",
+ .maxtype = __IFLA_VLAN_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,
+};
+
+struct rmnet_real_dev_info*
+rmnet_get_real_dev_info(struct net_device *real_dev)
+{
+ return __rmnet_get_real_dev_info(real_dev);
+}
+
+/* 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)
+{
+ unregister_netdevice_notifier(&rmnet_dev_notifier);
+ rtnl_link_unregister(&rmnet_link_ops);
+}
+
+module_init(rmnet_init)
+module_exit(rmnet_exit)
+MODULE_LICENSE("GPL v2");
--- /dev/null
+/* Copyright (c) 2013-2014, 2016-2017 The Linux Foundation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * RMNET Data configuration engine
+ *
+ */
+
+#include <linux/skbuff.h>
+
+#ifndef _RMNET_CONFIG_H_
+#define _RMNET_CONFIG_H_
+
+#define RMNET_MAX_LOGICAL_EP 255
+#define RMNET_MAX_VND 32
+
+/* Information about the next device to deliver the packet to.
+ * Exact usage of this parameter depends on the rmnet_mode.
+ */
+struct rmnet_endpoint {
+ u8 rmnet_mode;
+ u8 mux_id;
+ struct net_device *egress_dev;
+};
+
+/* One instance of this structure is instantiated for each real_dev associated
+ * with rmnet.
+ */
+struct rmnet_real_dev_info {
+ struct net_device *dev;
+ struct rmnet_endpoint local_ep;
+ struct rmnet_endpoint muxed_ep[RMNET_MAX_LOGICAL_EP];
+ u32 ingress_data_format;
+ u32 egress_data_format;
+ struct net_device *rmnet_devices[RMNET_MAX_VND];
+ u8 nr_rmnet_devs;
+};
+
+extern struct rtnl_link_ops rmnet_link_ops;
+
+struct rmnet_priv {
+ struct rmnet_endpoint local_ep;
+ u8 mux_id;
+};
+
+struct rmnet_real_dev_info*
+rmnet_get_real_dev_info(struct net_device *real_dev);
+
+#endif /* _RMNET_CONFIG_H_ */
--- /dev/null
+/* Copyright (c) 2013-2017, The Linux Foundation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * RMNET Data ingress/egress handler
+ *
+ */
+
+#include <linux/netdevice.h>
+#include <linux/netdev_features.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 rx_handler_result_t
+rmnet_bridge_handler(struct sk_buff *skb, struct rmnet_endpoint *ep)
+{
+ if (!ep->egress_dev)
+ kfree_skb(skb);
+ else
+ rmnet_egress_handler(skb, ep);
+
+ return RX_HANDLER_CONSUMED;
+}
+
+static rx_handler_result_t
+rmnet_deliver_skb(struct sk_buff *skb, struct rmnet_endpoint *ep)
+{
+ switch (ep->rmnet_mode) {
+ case RMNET_EPMODE_NONE:
+ return RX_HANDLER_PASS;
+
+ case RMNET_EPMODE_BRIDGE:
+ return rmnet_bridge_handler(skb, ep);
+
+ case RMNET_EPMODE_VND:
+ 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);
+ netif_receive_skb(skb);
+ return RX_HANDLER_CONSUMED;
+
+ default:
+ kfree_skb(skb);
+ return RX_HANDLER_CONSUMED;
+ }
+}
+
+static rx_handler_result_t
+rmnet_ingress_deliver_packet(struct sk_buff *skb,
+ struct rmnet_real_dev_info *r)
+{
+ if (!r) {
+ kfree_skb(skb);
+ return RX_HANDLER_CONSUMED;
+ }
+
+ skb->dev = r->local_ep.egress_dev;
+
+ return rmnet_deliver_skb(skb, &r->local_ep);
+}
+
+/* MAP handler */
+
+static rx_handler_result_t
+__rmnet_map_ingress_handler(struct sk_buff *skb,
+ struct rmnet_real_dev_info *r)
+{
+ struct rmnet_endpoint *ep;
+ u8 mux_id;
+ u16 len;
+
+ if (RMNET_MAP_GET_CD_BIT(skb)) {
+ if (r->ingress_data_format
+ & RMNET_INGRESS_FORMAT_MAP_COMMANDS)
+ return rmnet_map_command(skb, r);
+
+ kfree_skb(skb);
+ return RX_HANDLER_CONSUMED;
+ }
+
+ mux_id = RMNET_MAP_GET_MUX_ID(skb);
+ len = RMNET_MAP_GET_LENGTH(skb) - RMNET_MAP_GET_PAD(skb);
+
+ if (mux_id >= RMNET_MAX_LOGICAL_EP) {
+ kfree_skb(skb);
+ return RX_HANDLER_CONSUMED;
+ }
+
+ ep = &r->muxed_ep[mux_id];
+
+ if (r->ingress_data_format & RMNET_INGRESS_FORMAT_DEMUXING)
+ skb->dev = ep->egress_dev;
+
+ /* Subtract MAP header */
+ skb_pull(skb, sizeof(struct rmnet_map_header));
+ skb_trim(skb, len);
+ rmnet_set_skb_proto(skb);
+ return rmnet_deliver_skb(skb, ep);
+}
+
+static rx_handler_result_t
+rmnet_map_ingress_handler(struct sk_buff *skb,
+ struct rmnet_real_dev_info *r)
+{
+ struct sk_buff *skbn;
+ int rc;
+
+ if (r->ingress_data_format & RMNET_INGRESS_FORMAT_DEAGGREGATION) {
+ while ((skbn = rmnet_map_deaggregate(skb, r)) != NULL)
+ __rmnet_map_ingress_handler(skbn, r);
+
+ consume_skb(skb);
+ rc = RX_HANDLER_CONSUMED;
+ } else {
+ rc = __rmnet_map_ingress_handler(skb, r);
+ }
+
+ return rc;
+}
+
+static int rmnet_map_egress_handler(struct sk_buff *skb,
+ struct rmnet_real_dev_info *r,
+ struct rmnet_endpoint *ep,
+ struct net_device *orig_dev)
+{
+ int required_headroom, additional_header_len;
+ struct rmnet_map_header *map_header;
+
+ additional_header_len = 0;
+ required_headroom = sizeof(struct rmnet_map_header);
+
+ if (skb_headroom(skb) < required_headroom) {
+ if (pskb_expand_head(skb, required_headroom, 0, GFP_KERNEL))
+ return RMNET_MAP_CONSUMED;
+ }
+
+ map_header = rmnet_map_add_map_header(skb, additional_header_len, 0);
+ if (!map_header)
+ return RMNET_MAP_CONSUMED;
+
+ if (r->egress_data_format & RMNET_EGRESS_FORMAT_MUXING) {
+ if (ep->mux_id == 0xff)
+ map_header->mux_id = 0;
+ else
+ map_header->mux_id = ep->mux_id;
+ }
+
+ skb->protocol = htons(ETH_P_MAP);
+
+ return RMNET_MAP_SUCCESS;
+}
+
+/* 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 rmnet_real_dev_info *r;
+ struct sk_buff *skb = *pskb;
+ struct net_device *dev;
+ int rc;
+
+ if (!skb)
+ return RX_HANDLER_CONSUMED;
+
+ dev = skb->dev;
+ r = rmnet_get_real_dev_info(dev);
+
+ if (r->ingress_data_format & RMNET_INGRESS_FORMAT_MAP) {
+ rc = rmnet_map_ingress_handler(skb, r);
+ } else {
+ switch (ntohs(skb->protocol)) {
+ case ETH_P_MAP:
+ if (r->local_ep.rmnet_mode ==
+ RMNET_EPMODE_BRIDGE) {
+ rc = rmnet_ingress_deliver_packet(skb, r);
+ } else {
+ kfree_skb(skb);
+ rc = RX_HANDLER_CONSUMED;
+ }
+ break;
+
+ case ETH_P_IP:
+ case ETH_P_IPV6:
+ rc = rmnet_ingress_deliver_packet(skb, r);
+ break;
+
+ default:
+ rc = RX_HANDLER_PASS;
+ }
+ }
+
+ return rc;
+}
+
+/* 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 rmnet_endpoint *ep)
+{
+ struct rmnet_real_dev_info *r;
+ struct net_device *orig_dev;
+
+ orig_dev = skb->dev;
+ skb->dev = ep->egress_dev;
+
+ r = rmnet_get_real_dev_info(skb->dev);
+ if (!r) {
+ kfree_skb(skb);
+ return;
+ }
+
+ if (r->egress_data_format & RMNET_EGRESS_FORMAT_MAP) {
+ switch (rmnet_map_egress_handler(skb, r, ep, orig_dev)) {
+ case RMNET_MAP_CONSUMED:
+ return;
+
+ case RMNET_MAP_SUCCESS:
+ break;
+
+ default:
+ kfree_skb(skb);
+ return;
+ }
+ }
+
+ if (ep->rmnet_mode == RMNET_EPMODE_VND)
+ rmnet_vnd_tx_fixup(skb, orig_dev);
+
+ dev_queue_xmit(skb);
+}
--- /dev/null
+/* Copyright (c) 2013, 2016-2017 The Linux Foundation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * 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,
+ struct rmnet_endpoint *ep);
+
+rx_handler_result_t rmnet_rx_handler(struct sk_buff **pskb);
+
+#endif /* _RMNET_HANDLERS_H_ */
--- /dev/null
+/* Copyright (c) 2013-2017, The Linux Foundation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#ifndef _RMNET_MAP_H_
+#define _RMNET_MAP_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;
+ u16 flow_control_seq_num;
+ u32 qos_id;
+ } flow_control;
+ u8 data[0];
+ };
+} __aligned(1);
+
+enum rmnet_map_results {
+ RMNET_MAP_SUCCESS,
+ RMNET_MAP_CONSUMED,
+ RMNET_MAP_GENERAL_FAILURE,
+ RMNET_MAP_NOT_ENABLED,
+ RMNET_MAP_FAILED_AGGREGATION,
+ RMNET_MAP_FAILED_MUX
+};
+
+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
+};
+
+struct rmnet_map_header {
+ u8 pad_len:6;
+ u8 reserved_bit:1;
+ u8 cd_bit:1;
+ u8 mux_id;
+ u16 pkt_len;
+} __aligned(1);
+
+#define RMNET_MAP_GET_MUX_ID(Y) (((struct rmnet_map_header *) \
+ (Y)->data)->mux_id)
+#define RMNET_MAP_GET_CD_BIT(Y) (((struct rmnet_map_header *) \
+ (Y)->data)->cd_bit)
+#define RMNET_MAP_GET_PAD(Y) (((struct rmnet_map_header *) \
+ (Y)->data)->pad_len)
+#define RMNET_MAP_GET_CMD_START(Y) ((struct rmnet_map_control_command *) \
+ ((Y)->data + \
+ sizeof(struct rmnet_map_header)))
+#define RMNET_MAP_GET_LENGTH(Y) (ntohs(((struct rmnet_map_header *) \
+ (Y)->data)->pkt_len))
+
+#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
+
+u8 rmnet_map_demultiplex(struct sk_buff *skb);
+struct sk_buff *rmnet_map_deaggregate(struct sk_buff *skb,
+ struct rmnet_real_dev_info *rdinfo);
+
+struct rmnet_map_header *rmnet_map_add_map_header(struct sk_buff *skb,
+ int hdrlen, int pad);
+rx_handler_result_t rmnet_map_command(struct sk_buff *skb,
+ struct rmnet_real_dev_info *rdinfo);
+
+#endif /* _RMNET_MAP_H_ */
--- /dev/null
+/* Copyright (c) 2013-2017, The Linux Foundation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#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_real_dev_info *rdinfo,
+ int enable)
+{
+ struct rmnet_map_control_command *cmd;
+ struct rmnet_endpoint *ep;
+ struct net_device *vnd;
+ u16 ip_family;
+ u16 fc_seq;
+ u32 qos_id;
+ u8 mux_id;
+ int r;
+
+ mux_id = RMNET_MAP_GET_MUX_ID(skb);
+ cmd = RMNET_MAP_GET_CMD_START(skb);
+
+ if (mux_id >= RMNET_MAX_LOGICAL_EP) {
+ kfree_skb(skb);
+ return RX_HANDLER_CONSUMED;
+ }
+
+ ep = &rdinfo->muxed_ep[mux_id];
+ vnd = ep->egress_dev;
+
+ ip_family = cmd->flow_control.ip_family;
+ fc_seq = ntohs(cmd->flow_control.flow_control_seq_num);
+ qos_id = ntohl(cmd->flow_control.qos_id);
+
+ /* 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_real_dev_info *rdinfo)
+{
+ struct rmnet_map_control_command *cmd;
+ int xmit_status;
+
+ skb->protocol = htons(ETH_P_MAP);
+
+ cmd = RMNET_MAP_GET_CMD_START(skb);
+ cmd->cmd_type = type & 0x03;
+
+ netif_tx_lock(skb->dev);
+ xmit_status = skb->dev->netdev_ops->ndo_start_xmit(skb, skb->dev);
+ netif_tx_unlock(skb->dev);
+}
+
+/* Process MAP command frame and send N/ACK message as appropriate. Message cmd
+ * name is decoded here and appropriate handler is called.
+ */
+rx_handler_result_t rmnet_map_command(struct sk_buff *skb,
+ struct rmnet_real_dev_info *rdinfo)
+{
+ struct rmnet_map_control_command *cmd;
+ unsigned char command_name;
+ unsigned char rc = 0;
+
+ cmd = RMNET_MAP_GET_CMD_START(skb);
+ command_name = cmd->command_name;
+
+ switch (command_name) {
+ case RMNET_MAP_COMMAND_FLOW_ENABLE:
+ rc = rmnet_map_do_flow_control(skb, rdinfo, 1);
+ break;
+
+ case RMNET_MAP_COMMAND_FLOW_DISABLE:
+ rc = rmnet_map_do_flow_control(skb, rdinfo, 0);
+ break;
+
+ default:
+ rc = RMNET_MAP_COMMAND_UNSUPPORTED;
+ kfree_skb(skb);
+ break;
+ }
+ if (rc == RMNET_MAP_COMMAND_ACK)
+ rmnet_map_send_ack(skb, rc, rdinfo);
+ return RX_HANDLER_CONSUMED;
+}
--- /dev/null
+/* Copyright (c) 2013-2017, The Linux Foundation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * RMNET Data MAP protocol
+ *
+ */
+
+#include <linux/netdevice.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)
+
+/* 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, int pad)
+{
+ struct rmnet_map_header *map_header;
+ u32 padding, map_datalen;
+ u8 *padbytes;
+
+ if (skb_headroom(skb) < sizeof(struct rmnet_map_header))
+ return NULL;
+
+ 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));
+
+ if (pad == RMNET_MAP_NO_PAD_BYTES) {
+ map_header->pkt_len = htons(map_datalen);
+ return map_header;
+ }
+
+ padding = ALIGN(map_datalen, 4) - map_datalen;
+
+ if (padding == 0)
+ goto done;
+
+ if (skb_tailroom(skb) < padding)
+ return NULL;
+
+ padbytes = (u8 *)skb_put(skb, padding);
+ memset(padbytes, 0, padding);
+
+done:
+ map_header->pkt_len = htons(map_datalen + padding);
+ map_header->pad_len = padding & 0x3F;
+
+ 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_real_dev_info *rdinfo)
+{
+ struct rmnet_map_header *maph;
+ struct sk_buff *skbn;
+ u32 packet_len;
+
+ if (skb->len == 0)
+ return NULL;
+
+ maph = (struct rmnet_map_header *)skb->data;
+ packet_len = ntohs(maph->pkt_len) + sizeof(struct rmnet_map_header);
+
+ if (((int)skb->len - (int)packet_len) < 0)
+ return NULL;
+
+ skbn = alloc_skb(packet_len + RMNET_MAP_DEAGGR_SPACING, GFP_ATOMIC);
+ if (!skbn)
+ return NULL;
+
+ skbn->dev = skb->dev;
+ skb_reserve(skbn, RMNET_MAP_DEAGGR_HEADROOM);
+ skb_put(skbn, packet_len);
+ memcpy(skbn->data, skb->data, packet_len);
+ skb_pull(skb, packet_len);
+
+ /* Some hardware can send us empty frames. Catch them */
+ if (ntohs(maph->pkt_len) == 0) {
+ kfree_skb(skb);
+ return NULL;
+ }
+
+ return skbn;
+}
--- /dev/null
+/* Copyright (c) 2013-2014, 2016-2017 The Linux Foundation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#ifndef _RMNET_PRIVATE_H_
+#define _RMNET_PRIVATE_H_
+
+#define RMNET_MAX_VND 32
+#define RMNET_MAX_PACKET_SIZE 16384
+#define RMNET_DFLT_PACKET_SIZE 1500
+#define RMNET_NEEDED_HEADROOM 16
+#define RMNET_TX_QUEUE_LEN 1000
+
+/* Constants */
+#define RMNET_EGRESS_FORMAT__RESERVED__ BIT(0)
+#define RMNET_EGRESS_FORMAT_MAP BIT(1)
+#define RMNET_EGRESS_FORMAT_AGGREGATION BIT(2)
+#define RMNET_EGRESS_FORMAT_MUXING BIT(3)
+#define RMNET_EGRESS_FORMAT_MAP_CKSUMV3 BIT(4)
+#define RMNET_EGRESS_FORMAT_MAP_CKSUMV4 BIT(5)
+
+#define RMNET_INGRESS_FIX_ETHERNET BIT(0)
+#define RMNET_INGRESS_FORMAT_MAP BIT(1)
+#define RMNET_INGRESS_FORMAT_DEAGGREGATION BIT(2)
+#define RMNET_INGRESS_FORMAT_DEMUXING BIT(3)
+#define RMNET_INGRESS_FORMAT_MAP_COMMANDS BIT(4)
+#define RMNET_INGRESS_FORMAT_MAP_CKSUMV3 BIT(5)
+#define RMNET_INGRESS_FORMAT_MAP_CKSUMV4 BIT(6)
+
+/* Pass the frame up the stack with no modifications to skb->dev */
+#define RMNET_EPMODE_NONE (0)
+/* 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_ */
--- /dev/null
+/* Copyright (c) 2013-2017, The Linux Foundation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ *
+ * RMNET Data virtual network driver
+ *
+ */
+
+#include <linux/etherdevice.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)
+{
+ dev->stats.rx_packets++;
+ dev->stats.rx_bytes += skb->len;
+}
+
+void rmnet_vnd_tx_fixup(struct sk_buff *skb, struct net_device *dev)
+{
+ dev->stats.tx_packets++;
+ dev->stats.tx_bytes += skb->len;
+}
+
+/* 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->local_ep.egress_dev) {
+ rmnet_egress_handler(skb, &priv->local_ep);
+ } else {
+ dev->stats.tx_dropped++;
+ kfree_skb(skb);
+ }
+ return NETDEV_TX_OK;
+}
+
+static int rmnet_vnd_change_mtu(struct net_device *rmnet_dev, int new_mtu)
+{
+ if (new_mtu < 0 || new_mtu > RMNET_MAX_PACKET_SIZE)
+ return -EINVAL;
+
+ rmnet_dev->mtu = new_mtu;
+ return 0;
+}
+
+static const struct net_device_ops rmnet_vnd_ops = {
+ .ndo_start_xmit = rmnet_vnd_start_xmit,
+ .ndo_change_mtu = rmnet_vnd_change_mtu,
+};
+
+/* 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)
+{
+ struct rmnet_priv *priv;
+
+ priv = netdev_priv(rmnet_dev);
+ netdev_dbg(rmnet_dev, "Setting up device %s\n", rmnet_dev->name);
+
+ rmnet_dev->netdev_ops = &rmnet_vnd_ops;
+ rmnet_dev->mtu = RMNET_DFLT_PACKET_SIZE;
+ rmnet_dev->needed_headroom = RMNET_NEEDED_HEADROOM;
+ random_ether_addr(rmnet_dev->dev_addr);
+ 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;
+}
+
+/* Exposed API */
+
+int rmnet_vnd_newlink(u8 id, struct net_device *rmnet_dev,
+ struct rmnet_real_dev_info *r)
+{
+ int rc;
+
+ if (r->rmnet_devices[id])
+ return -EINVAL;
+
+ rc = register_netdevice(rmnet_dev);
+ if (!rc) {
+ r->rmnet_devices[id] = rmnet_dev;
+ r->nr_rmnet_devs++;
+ rmnet_dev->rtnl_link_ops = &rmnet_link_ops;
+ }
+
+ return rc;
+}
+
+int rmnet_vnd_dellink(u8 id, struct rmnet_real_dev_info *r)
+{
+ if (id >= RMNET_MAX_VND || !r->rmnet_devices[id])
+ return -EINVAL;
+
+ r->rmnet_devices[id] = NULL;
+ r->nr_rmnet_devs--;
+ return 0;
+}
+
+u8 rmnet_vnd_get_mux(struct net_device *rmnet_dev)
+{
+ struct rmnet_priv *priv;
+
+ priv = netdev_priv(rmnet_dev);
+ return priv->mux_id;
+}
+
+void rmnet_vnd_set_mux(struct net_device *rmnet_dev, u8 mux_id)
+{
+ struct rmnet_priv *priv;
+
+ priv = netdev_priv(rmnet_dev);
+ priv->mux_id = mux_id;
+}
+
+/* Gets the logical endpoint configuration for a RmNet virtual network device
+ * node. Caller should confirm that devices is a RmNet VND before calling.
+ */
+struct rmnet_endpoint *rmnet_vnd_get_endpoint(struct net_device *rmnet_dev)
+{
+ struct rmnet_priv *priv;
+
+ if (!rmnet_dev)
+ return NULL;
+
+ priv = netdev_priv(rmnet_dev);
+
+ return &priv->local_ep;
+}
+
+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;
+}
--- /dev/null
+/* Copyright (c) 2013-2017, The Linux Foundation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * 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);
+struct rmnet_endpoint *rmnet_vnd_get_endpoint(struct net_device *dev);
+int rmnet_vnd_newlink(u8 id, struct net_device *rmnet_dev,
+ struct rmnet_real_dev_info *r);
+int rmnet_vnd_dellink(u8 id, struct rmnet_real_dev_info *r);
+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);
+u8 rmnet_vnd_get_mux(struct net_device *rmnet_dev);
+void rmnet_vnd_set_mux(struct net_device *rmnet_dev, u8 mux_id);
+void rmnet_vnd_setup(struct net_device *dev);
+#endif /* _RMNET_VND_H_ */