// 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);
}