1/*
2 * Data gathering module for Linux-VM Monitor Stream, Stage 1.
3 * Collects accumulated network statistics (Packets received/transmitted,
4 * dropped, errors, ...).
5 *
6 * Copyright IBM Corp. 2003, 2006
7 *
8 * Author: Gerald Schaefer <gerald.schaefer@de.ibm.com>
9 */
10
11#include <linux/module.h>
12#include <linux/init.h>
13#include <linux/errno.h>
14#include <linux/kernel_stat.h>
15#include <linux/netdevice.h>
16#include <net/net_namespace.h>
17
18#include "appldata.h"
19
20
21/*
22 * Network data
23 *
24 * This is accessed as binary data by z/VM. If changes to it can't be avoided,
25 * the structure version (product ID, see appldata_base.c) needs to be changed
26 * as well and all documentation and z/VM applications using it must be updated.
27 *
28 * The record layout is documented in the Linux for zSeries Device Drivers
29 * book:
30 * http://oss.software.ibm.com/developerworks/opensource/linux390/index.shtml
31 */
32struct appldata_net_sum_data {
33	u64 timestamp;
34	u32 sync_count_1;	/* after VM collected the record data, */
35	u32 sync_count_2;	/* sync_count_1 and sync_count_2 should be the
36				   same. If not, the record has been updated on
37				   the Linux side while VM was collecting the
38				   (possibly corrupt) data */
39
40	u32 nr_interfaces;	/* nr. of network interfaces being monitored */
41
42	u32 padding;		/* next value is 64-bit aligned, so these */
43				/* 4 byte would be padded out by compiler */
44
45	u64 rx_packets;		/* total packets received        */
46	u64 tx_packets;		/* total packets transmitted     */
47	u64 rx_bytes;		/* total bytes received          */
48	u64 tx_bytes;		/* total bytes transmitted       */
49	u64 rx_errors;		/* bad packets received          */
50	u64 tx_errors;		/* packet transmit problems      */
51	u64 rx_dropped;		/* no space in linux buffers     */
52	u64 tx_dropped;		/* no space available in linux   */
53	u64 collisions;		/* collisions while transmitting */
54} __packed;
55
56
57/*
58 * appldata_get_net_sum_data()
59 *
60 * gather accumulated network statistics
61 */
62static void appldata_get_net_sum_data(void *data)
63{
64	int i;
65	struct appldata_net_sum_data *net_data;
66	struct net_device *dev;
67	unsigned long rx_packets, tx_packets, rx_bytes, tx_bytes, rx_errors,
68			tx_errors, rx_dropped, tx_dropped, collisions;
69
70	net_data = data;
71	net_data->sync_count_1++;
72
73	i = 0;
74	rx_packets = 0;
75	tx_packets = 0;
76	rx_bytes   = 0;
77	tx_bytes   = 0;
78	rx_errors  = 0;
79	tx_errors  = 0;
80	rx_dropped = 0;
81	tx_dropped = 0;
82	collisions = 0;
83
84	rcu_read_lock();
85	for_each_netdev_rcu(&init_net, dev) {
86		const struct rtnl_link_stats64 *stats;
87		struct rtnl_link_stats64 temp;
88
89		stats = dev_get_stats(dev, &temp);
90		rx_packets += stats->rx_packets;
91		tx_packets += stats->tx_packets;
92		rx_bytes   += stats->rx_bytes;
93		tx_bytes   += stats->tx_bytes;
94		rx_errors  += stats->rx_errors;
95		tx_errors  += stats->tx_errors;
96		rx_dropped += stats->rx_dropped;
97		tx_dropped += stats->tx_dropped;
98		collisions += stats->collisions;
99		i++;
100	}
101	rcu_read_unlock();
102
103	net_data->nr_interfaces = i;
104	net_data->rx_packets = rx_packets;
105	net_data->tx_packets = tx_packets;
106	net_data->rx_bytes   = rx_bytes;
107	net_data->tx_bytes   = tx_bytes;
108	net_data->rx_errors  = rx_errors;
109	net_data->tx_errors  = tx_errors;
110	net_data->rx_dropped = rx_dropped;
111	net_data->tx_dropped = tx_dropped;
112	net_data->collisions = collisions;
113
114	net_data->timestamp = get_tod_clock();
115	net_data->sync_count_2++;
116}
117
118
119static struct appldata_ops ops = {
120	.name	   = "net_sum",
121	.record_nr = APPLDATA_RECORD_NET_SUM_ID,
122	.size	   = sizeof(struct appldata_net_sum_data),
123	.callback  = &appldata_get_net_sum_data,
124	.owner     = THIS_MODULE,
125	.mod_lvl   = {0xF0, 0xF0},		/* EBCDIC "00" */
126};
127
128
129/*
130 * appldata_net_init()
131 *
132 * init data, register ops
133 */
134static int __init appldata_net_init(void)
135{
136	int ret;
137
138	ops.data = kzalloc(sizeof(struct appldata_net_sum_data), GFP_KERNEL);
139	if (!ops.data)
140		return -ENOMEM;
141
142	ret = appldata_register_ops(&ops);
143	if (ret)
144		kfree(ops.data);
145
146	return ret;
147}
148
149/*
150 * appldata_net_exit()
151 *
152 * unregister ops
153 */
154static void __exit appldata_net_exit(void)
155{
156	appldata_unregister_ops(&ops);
157	kfree(ops.data);
158}
159
160
161module_init(appldata_net_init);
162module_exit(appldata_net_exit);
163
164MODULE_LICENSE("GPL");
165MODULE_AUTHOR("Gerald Schaefer");
166MODULE_DESCRIPTION("Linux-VM Monitor Stream, accumulated network statistics");
167