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 */
29 struct 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 */
appldata_get_net_sum_data(void * data)59 static 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
116 static 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 */
appldata_net_init(void)131 static 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 */
appldata_net_exit(void)151 static void __exit appldata_net_exit(void)
152 {
153 appldata_unregister_ops(&ops);
154 kfree(ops.data);
155 }
156
157
158 module_init(appldata_net_init);
159 module_exit(appldata_net_exit);
160
161 MODULE_LICENSE("GPL");
162 MODULE_AUTHOR("Gerald Schaefer");
163 MODULE_DESCRIPTION("Linux-VM Monitor Stream, accumulated network statistics");
164