1 // SPDX-License-Identifier: GPL-2.0-only
2 /* Copyright (c) 2013-2018, The Linux Foundation. All rights reserved.
3 */
4
5 #include <linux/netdevice.h>
6 #include "rmnet_config.h"
7 #include "rmnet_map.h"
8 #include "rmnet_private.h"
9 #include "rmnet_vnd.h"
10
rmnet_map_do_flow_control(struct sk_buff * skb,struct rmnet_port * port,int enable)11 static u8 rmnet_map_do_flow_control(struct sk_buff *skb,
12 struct rmnet_port *port,
13 int enable)
14 {
15 struct rmnet_endpoint *ep;
16 struct net_device *vnd;
17 u8 mux_id;
18 int r;
19
20 mux_id = RMNET_MAP_GET_MUX_ID(skb);
21
22 if (mux_id >= RMNET_MAX_LOGICAL_EP) {
23 kfree_skb(skb);
24 return RX_HANDLER_CONSUMED;
25 }
26
27 ep = rmnet_get_endpoint(port, mux_id);
28 if (!ep) {
29 kfree_skb(skb);
30 return RX_HANDLER_CONSUMED;
31 }
32
33 vnd = ep->egress_dev;
34
35 /* Ignore the ip family and pass the sequence number for both v4 and v6
36 * sequence. User space does not support creating dedicated flows for
37 * the 2 protocols
38 */
39 r = rmnet_vnd_do_flow_control(vnd, enable);
40 if (r) {
41 kfree_skb(skb);
42 return RMNET_MAP_COMMAND_UNSUPPORTED;
43 } else {
44 return RMNET_MAP_COMMAND_ACK;
45 }
46 }
47
rmnet_map_send_ack(struct sk_buff * skb,unsigned char type,struct rmnet_port * port)48 static void rmnet_map_send_ack(struct sk_buff *skb,
49 unsigned char type,
50 struct rmnet_port *port)
51 {
52 struct rmnet_map_control_command *cmd;
53 struct net_device *dev = skb->dev;
54
55 if (port->data_format & RMNET_FLAGS_INGRESS_MAP_CKSUMV4)
56 skb_trim(skb,
57 skb->len - sizeof(struct rmnet_map_dl_csum_trailer));
58
59 skb->protocol = htons(ETH_P_MAP);
60
61 cmd = RMNET_MAP_GET_CMD_START(skb);
62 cmd->cmd_type = type & 0x03;
63
64 netif_tx_lock(dev);
65 dev->netdev_ops->ndo_start_xmit(skb, dev);
66 netif_tx_unlock(dev);
67 }
68
69 /* Process MAP command frame and send N/ACK message as appropriate. Message cmd
70 * name is decoded here and appropriate handler is called.
71 */
rmnet_map_command(struct sk_buff * skb,struct rmnet_port * port)72 void rmnet_map_command(struct sk_buff *skb, struct rmnet_port *port)
73 {
74 struct rmnet_map_control_command *cmd;
75 unsigned char command_name;
76 unsigned char rc = 0;
77
78 cmd = RMNET_MAP_GET_CMD_START(skb);
79 command_name = cmd->command_name;
80
81 switch (command_name) {
82 case RMNET_MAP_COMMAND_FLOW_ENABLE:
83 rc = rmnet_map_do_flow_control(skb, port, 1);
84 break;
85
86 case RMNET_MAP_COMMAND_FLOW_DISABLE:
87 rc = rmnet_map_do_flow_control(skb, port, 0);
88 break;
89
90 default:
91 rc = RMNET_MAP_COMMAND_UNSUPPORTED;
92 kfree_skb(skb);
93 break;
94 }
95 if (rc == RMNET_MAP_COMMAND_ACK)
96 rmnet_map_send_ack(skb, rc, port);
97 }
98
