arch/s390/appldata/appldata_net_sum.c

   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  * The record layout is documented in the Linux for zSeries Device Drivers
  30  * book:
  31  * http://oss.software.ibm.com/developerworks/opensource/linux390/index.shtml
  32  */
  33 struct appldata_net_sum_data {
  34         u64 timestamp;
  35         u32 sync_count_1;       /* after VM collected the record data, */
  36         u32 sync_count_2;       /* sync_count_1 and sync_count_2 should be the
  37                                    same. If not, the record has been updated on
  38                                    the Linux side while VM was collecting the
  39                                    (possibly corrupt) data */
  40
  41         u32 nr_interfaces;      /* nr. of network interfaces being monitored */
  42
  43         u32 padding;            /* next value is 64-bit aligned, so these */
  44                                 /* 4 byte would be padded out by compiler */
  45
  46         u64 rx_packets;         /* total packets received        */
  47         u64 tx_packets;         /* total packets transmitted     */
  48         u64 rx_bytes;           /* total bytes received          */
  49         u64 tx_bytes;           /* total bytes transmitted       */
  50         u64 rx_errors;          /* bad packets received          */
  51         u64 tx_errors;          /* packet transmit problems      */
  52         u64 rx_dropped;         /* no space in linux buffers     */
  53         u64 tx_dropped;         /* no space available in linux   */
  54         u64 collisions;         /* collisions while transmitting */
  55 } __packed;
  56
  57
  58 /*
  59  * appldata_get_net_sum_data()
  60  *
  61  * gather accumulated network statistics
  62  */
  63 static void appldata_get_net_sum_data(void *data)
  64 {
  65         int i;
  66         struct appldata_net_sum_data *net_data;
  67         struct net_device *dev;
  68         unsigned long rx_packets, tx_packets, rx_bytes, tx_bytes, rx_errors,
  69                         tx_errors, rx_dropped, tx_dropped, collisions;
  70
  71         net_data = data;
  72         net_data->sync_count_1++;
  73
  74         i = 0;
  75         rx_packets = 0;
  76         tx_packets = 0;
  77         rx_bytes   = 0;
  78         tx_bytes   = 0;
  79         rx_errors  = 0;
  80         tx_errors  = 0;
  81         rx_dropped = 0;
  82         tx_dropped = 0;
  83         collisions = 0;
  84
  85         rcu_read_lock();
  86         for_each_netdev_rcu(&init_net, dev) {
  87                 const struct rtnl_link_stats64 *stats;
  88                 struct rtnl_link_stats64 temp;
  89
  90                 stats = dev_get_stats(dev, &temp);
  91                 rx_packets += stats->rx_packets;
  92                 tx_packets += stats->tx_packets;
  93                 rx_bytes   += stats->rx_bytes;
  94                 tx_bytes   += stats->tx_bytes;
  95                 rx_errors  += stats->rx_errors;
  96                 tx_errors  += stats->tx_errors;
  97                 rx_dropped += stats->rx_dropped;
  98                 tx_dropped += stats->tx_dropped;
  99                 collisions += stats->collisions;
 100                 i++;
 101         }
 102         rcu_read_unlock();
 103
 104         net_data->nr_interfaces = i;
 105         net_data->rx_packets = rx_packets;
 106         net_data->tx_packets = tx_packets;
 107         net_data->rx_bytes   = rx_bytes;
 108         net_data->tx_bytes   = tx_bytes;
 109         net_data->rx_errors  = rx_errors;
 110         net_data->tx_errors  = tx_errors;
 111         net_data->rx_dropped = rx_dropped;
 112         net_data->tx_dropped = tx_dropped;
 113         net_data->collisions = collisions;
 114
 115         net_data->timestamp = get_tod_clock();
 116         net_data->sync_count_2++;
 117 }
 118
 119
 120 static struct appldata_ops ops = {
 121         .name      = "net_sum",
 122         .record_nr = APPLDATA_RECORD_NET_SUM_ID,
 123         .size      = sizeof(struct appldata_net_sum_data),
 124         .callback  = &appldata_get_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         int ret;
 138
 139         ops.data = kzalloc(sizeof(struct appldata_net_sum_data), GFP_KERNEL);
 140         if (!ops.data)
 141                 return -ENOMEM;
 142
 143         ret = appldata_register_ops(&ops);
 144         if (ret)
 145                 kfree(ops.data);
 146
 147         return ret;
 148 }
 149
 150 /*
 151  * appldata_net_exit()
 152  *
 153  * unregister ops
 154  */
 155 static void __exit appldata_net_exit(void)
 156 {
 157         appldata_unregister_ops(&ops);
 158         kfree(ops.data);
 159 }
 160
 161
 162 module_init(appldata_net_init);
 163 module_exit(appldata_net_exit);
 164
 165 MODULE_LICENSE("GPL");
 166 MODULE_AUTHOR("Gerald Schaefer");
 167 MODULE_DESCRIPTION("Linux-VM Monitor Stream, accumulated network statistics");