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  */
32 static struct 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 } __attribute__((packed)) appldata_net_sum_data;
55 
56 
57 /*
58  * appldata_get_net_sum_data()
59  *
60  * gather accumulated network statistics
61  */
62 static 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_clock();
115 	net_data->sync_count_2++;
116 }
117 
118 
119 static 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 	.data      = &appldata_net_sum_data,
125 	.owner     = THIS_MODULE,
126 	.mod_lvl   = {0xF0, 0xF0},		/* EBCDIC "00" */
127 };
128 
129 
130 /*
131  * appldata_net_init()
132  *
133  * init data, register ops
134  */
135 static int __init appldata_net_init(void)
136 {
137 	return appldata_register_ops(&ops);
138 }
139 
140 /*
141  * appldata_net_exit()
142  *
143  * unregister ops
144  */
145 static void __exit appldata_net_exit(void)
146 {
147 	appldata_unregister_ops(&ops);
148 }
149 
150 
151 module_init(appldata_net_init);
152 module_exit(appldata_net_exit);
153 
154 MODULE_LICENSE("GPL");
155 MODULE_AUTHOR("Gerald Schaefer");
156 MODULE_DESCRIPTION("Linux-VM Monitor Stream, accumulated network statistics");
157