1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Data gathering module for Linux-VM Monitor Stream, Stage 1.
4 * Collects accumulated network statistics (Packets received/transmitted,
5 * dropped, errors, ...).
6 *
7 * Copyright IBM Corp. 2003, 2006
8 *
9 * Author: Gerald Schaefer <gerald.schaefer@de.ibm.com>
10 */
11
12#include <linux/module.h>
13#include <linux/init.h>
14#include <linux/errno.h>
15#include <linux/kernel_stat.h>
16#include <linux/netdevice.h>
17#include <net/net_namespace.h>
18
19#include "appldata.h"
20
21
22/*
23 * Network data
24 *
25 * This is accessed as binary data by z/VM. If changes to it can't be avoided,
26 * the structure version (product ID, see appldata_base.c) needs to be changed
27 * as well and all documentation and z/VM applications using it must be updated.
28 */
29struct appldata_net_sum_data {
30	u64 timestamp;
31	u32 sync_count_1;	/* after VM collected the record data, */
32	u32 sync_count_2;	/* sync_count_1 and sync_count_2 should be the
33				   same. If not, the record has been updated on
34				   the Linux side while VM was collecting the
35				   (possibly corrupt) data */
36
37	u32 nr_interfaces;	/* nr. of network interfaces being monitored */
38
39	u32 padding;		/* next value is 64-bit aligned, so these */
40				/* 4 byte would be padded out by compiler */
41
42	u64 rx_packets;		/* total packets received        */
43	u64 tx_packets;		/* total packets transmitted     */
44	u64 rx_bytes;		/* total bytes received          */
45	u64 tx_bytes;		/* total bytes transmitted       */
46	u64 rx_errors;		/* bad packets received          */
47	u64 tx_errors;		/* packet transmit problems      */
48	u64 rx_dropped;		/* no space in linux buffers     */
49	u64 tx_dropped;		/* no space available in linux   */
50	u64 collisions;		/* collisions while transmitting */
51} __packed;
52
53
54/*
55 * appldata_get_net_sum_data()
56 *
57 * gather accumulated network statistics
58 */
59static void appldata_get_net_sum_data(void *data)
60{
61	int i;
62	struct appldata_net_sum_data *net_data;
63	struct net_device *dev;
64	unsigned long rx_packets, tx_packets, rx_bytes, tx_bytes, rx_errors,
65			tx_errors, rx_dropped, tx_dropped, collisions;
66
67	net_data = data;
68	net_data->sync_count_1++;
69
70	i = 0;
71	rx_packets = 0;
72	tx_packets = 0;
73	rx_bytes   = 0;
74	tx_bytes   = 0;
75	rx_errors  = 0;
76	tx_errors  = 0;
77	rx_dropped = 0;
78	tx_dropped = 0;
79	collisions = 0;
80
81	rcu_read_lock();
82	for_each_netdev_rcu(&init_net, dev) {
83		const struct rtnl_link_stats64 *stats;
84		struct rtnl_link_stats64 temp;
85
86		stats = dev_get_stats(dev, &temp);
87		rx_packets += stats->rx_packets;
88		tx_packets += stats->tx_packets;
89		rx_bytes   += stats->rx_bytes;
90		tx_bytes   += stats->tx_bytes;
91		rx_errors  += stats->rx_errors;
92		tx_errors  += stats->tx_errors;
93		rx_dropped += stats->rx_dropped;
94		tx_dropped += stats->tx_dropped;
95		collisions += stats->collisions;
96		i++;
97	}
98	rcu_read_unlock();
99
100	net_data->nr_interfaces = i;
101	net_data->rx_packets = rx_packets;
102	net_data->tx_packets = tx_packets;
103	net_data->rx_bytes   = rx_bytes;
104	net_data->tx_bytes   = tx_bytes;
105	net_data->rx_errors  = rx_errors;
106	net_data->tx_errors  = tx_errors;
107	net_data->rx_dropped = rx_dropped;
108	net_data->tx_dropped = tx_dropped;
109	net_data->collisions = collisions;
110
111	net_data->timestamp = get_tod_clock();
112	net_data->sync_count_2++;
113}
114
115
116static struct appldata_ops ops = {
117	.name	   = "net_sum",
118	.record_nr = APPLDATA_RECORD_NET_SUM_ID,
119	.size	   = sizeof(struct appldata_net_sum_data),
120	.callback  = &appldata_get_net_sum_data,
121	.owner     = THIS_MODULE,
122	.mod_lvl   = {0xF0, 0xF0},		/* EBCDIC "00" */
123};
124
125
126/*
127 * appldata_net_init()
128 *
129 * init data, register ops
130 */
131static int __init appldata_net_init(void)
132{
133	int ret;
134
135	ops.data = kzalloc(sizeof(struct appldata_net_sum_data), GFP_KERNEL);
136	if (!ops.data)
137		return -ENOMEM;
138
139	ret = appldata_register_ops(&ops);
140	if (ret)
141		kfree(ops.data);
142
143	return ret;
144}
145
146/*
147 * appldata_net_exit()
148 *
149 * unregister ops
150 */
151static void __exit appldata_net_exit(void)
152{
153	appldata_unregister_ops(&ops);
154	kfree(ops.data);
155}
156
157
158module_init(appldata_net_init);
159module_exit(appldata_net_exit);
160
161MODULE_LICENSE("GPL");
162MODULE_AUTHOR("Gerald Schaefer");
163MODULE_DESCRIPTION("Linux-VM Monitor Stream, accumulated network statistics");
164