LXR linux/include/net/snmp.h

   1/* SPDX-License-Identifier: GPL-2.0-or-later */
   2/*
   3 *
   4 *              SNMP MIB entries for the IP subsystem.
   5 *              
   6 *              Alan Cox <gw4pts@gw4pts.ampr.org>
   7 *
   8 *              We don't chose to implement SNMP in the kernel (this would
   9 *              be silly as SNMP is a pain in the backside in places). We do
  10 *              however need to collect the MIB statistics and export them
  11 *              out of /proc (eventually)
  12 */
  13 
  14#ifndef _SNMP_H
  15#define _SNMP_H
  16
  17#include <linux/cache.h>
  18#include <linux/snmp.h>
  19#include <linux/smp.h>
  20
  21/*
  22 * Mibs are stored in array of unsigned long.
  23 */
  24/*
  25 * struct snmp_mib{}
  26 *  - list of entries for particular API (such as /proc/net/snmp)
  27 *  - name of entries.
  28 */
  29struct snmp_mib {
  30        const char *name;
  31        int entry;
  32};
  33
  34#define SNMP_MIB_ITEM(_name,_entry)     {       \
  35        .name = _name,                          \
  36        .entry = _entry,                        \
  37}
  38
  39#define SNMP_MIB_SENTINEL {     \
  40        .name = NULL,           \
  41        .entry = 0,             \
  42}
  43
  44/*
  45 * We use unsigned longs for most mibs but u64 for ipstats.
  46 */
  47#include <linux/u64_stats_sync.h>
  48
  49/* IPstats */
  50#define IPSTATS_MIB_MAX __IPSTATS_MIB_MAX
  51struct ipstats_mib {
  52        /* mibs[] must be first field of struct ipstats_mib */
  53        u64             mibs[IPSTATS_MIB_MAX];
  54        struct u64_stats_sync syncp;
  55};
  56
  57/* ICMP */
  58#define ICMP_MIB_MAX    __ICMP_MIB_MAX
  59struct icmp_mib {
  60        unsigned long   mibs[ICMP_MIB_MAX];
  61};
  62
  63#define ICMPMSG_MIB_MAX __ICMPMSG_MIB_MAX
  64struct icmpmsg_mib {
  65        atomic_long_t   mibs[ICMPMSG_MIB_MAX];
  66};
  67
  68/* ICMP6 (IPv6-ICMP) */
  69#define ICMP6_MIB_MAX   __ICMP6_MIB_MAX
  70/* per network ns counters */
  71struct icmpv6_mib {
  72        unsigned long   mibs[ICMP6_MIB_MAX];
  73};
  74/* per device counters, (shared on all cpus) */
  75struct icmpv6_mib_device {
  76        atomic_long_t   mibs[ICMP6_MIB_MAX];
  77};
  78
  79#define ICMP6MSG_MIB_MAX  __ICMP6MSG_MIB_MAX
  80/* per network ns counters */
  81struct icmpv6msg_mib {
  82        atomic_long_t   mibs[ICMP6MSG_MIB_MAX];
  83};
  84/* per device counters, (shared on all cpus) */
  85struct icmpv6msg_mib_device {
  86        atomic_long_t   mibs[ICMP6MSG_MIB_MAX];
  87};
  88
  89
  90/* TCP */
  91#define TCP_MIB_MAX     __TCP_MIB_MAX
  92struct tcp_mib {
  93        unsigned long   mibs[TCP_MIB_MAX];
  94};
  95
  96/* UDP */
  97#define UDP_MIB_MAX     __UDP_MIB_MAX
  98struct udp_mib {
  99        unsigned long   mibs[UDP_MIB_MAX];
 100};
 101
 102/* Linux */
 103#define LINUX_MIB_MAX   __LINUX_MIB_MAX
 104struct linux_mib {
 105        unsigned long   mibs[LINUX_MIB_MAX];
 106};
 107
 108/* Linux Xfrm */
 109#define LINUX_MIB_XFRMMAX       __LINUX_MIB_XFRMMAX
 110struct linux_xfrm_mib {
 111        unsigned long   mibs[LINUX_MIB_XFRMMAX];
 112};
 113
 114#define DEFINE_SNMP_STAT(type, name)    \
 115        __typeof__(type) __percpu *name
 116#define DEFINE_SNMP_STAT_ATOMIC(type, name)     \
 117        __typeof__(type) *name
 118#define DECLARE_SNMP_STAT(type, name)   \
 119        extern __typeof__(type) __percpu *name
 120
 121#define __SNMP_INC_STATS(mib, field)    \
 122                        __this_cpu_inc(mib->mibs[field])
 123
 124#define SNMP_INC_STATS_ATOMIC_LONG(mib, field)  \
 125                        atomic_long_inc(&mib->mibs[field])
 126
 127#define SNMP_INC_STATS(mib, field)      \
 128                        this_cpu_inc(mib->mibs[field])
 129
 130#define SNMP_DEC_STATS(mib, field)      \
 131                        this_cpu_dec(mib->mibs[field])
 132
 133#define __SNMP_ADD_STATS(mib, field, addend)    \
 134                        __this_cpu_add(mib->mibs[field], addend)
 135
 136#define SNMP_ADD_STATS(mib, field, addend)      \
 137                        this_cpu_add(mib->mibs[field], addend)
 138#define SNMP_UPD_PO_STATS(mib, basefield, addend)       \
 139        do { \
 140                __typeof__((mib->mibs) + 0) ptr = mib->mibs;    \
 141                this_cpu_inc(ptr[basefield##PKTS]);             \
 142                this_cpu_add(ptr[basefield##OCTETS], addend);   \
 143        } while (0)
 144#define __SNMP_UPD_PO_STATS(mib, basefield, addend)     \
 145        do { \
 146                __typeof__((mib->mibs) + 0) ptr = mib->mibs;    \
 147                __this_cpu_inc(ptr[basefield##PKTS]);           \
 148                __this_cpu_add(ptr[basefield##OCTETS], addend); \
 149        } while (0)
 150
 151
 152#if BITS_PER_LONG==32
 153
 154#define __SNMP_ADD_STATS64(mib, field, addend)                          \
 155        do {                                                            \
 156                __typeof__(*mib) *ptr = raw_cpu_ptr(mib);               \
 157                u64_stats_update_begin(&ptr->syncp);                    \
 158                ptr->mibs[field] += addend;                             \
 159                u64_stats_update_end(&ptr->syncp);                      \
 160        } while (0)
 161
 162#define SNMP_ADD_STATS64(mib, field, addend)                            \
 163        do {                                                            \
 164                local_bh_disable();                                     \
 165                __SNMP_ADD_STATS64(mib, field, addend);                 \
 166                local_bh_enable();                              \
 167        } while (0)
 168
 169#define __SNMP_INC_STATS64(mib, field) SNMP_ADD_STATS64(mib, field, 1)
 170#define SNMP_INC_STATS64(mib, field) SNMP_ADD_STATS64(mib, field, 1)
 171#define __SNMP_UPD_PO_STATS64(mib, basefield, addend)                   \
 172        do {                                                            \
 173                __typeof__(*mib) *ptr;                          \
 174                ptr = raw_cpu_ptr((mib));                               \
 175                u64_stats_update_begin(&ptr->syncp);                    \
 176                ptr->mibs[basefield##PKTS]++;                           \
 177                ptr->mibs[basefield##OCTETS] += addend;                 \
 178                u64_stats_update_end(&ptr->syncp);                      \
 179        } while (0)
 180#define SNMP_UPD_PO_STATS64(mib, basefield, addend)                     \
 181        do {                                                            \
 182                local_bh_disable();                                     \
 183                __SNMP_UPD_PO_STATS64(mib, basefield, addend);          \
 184                local_bh_enable();                              \
 185        } while (0)
 186#else
 187#define __SNMP_INC_STATS64(mib, field)          __SNMP_INC_STATS(mib, field)
 188#define SNMP_INC_STATS64(mib, field)            SNMP_INC_STATS(mib, field)
 189#define SNMP_DEC_STATS64(mib, field)            SNMP_DEC_STATS(mib, field)
 190#define __SNMP_ADD_STATS64(mib, field, addend)  __SNMP_ADD_STATS(mib, field, addend)
 191#define SNMP_ADD_STATS64(mib, field, addend)    SNMP_ADD_STATS(mib, field, addend)
 192#define SNMP_UPD_PO_STATS64(mib, basefield, addend) SNMP_UPD_PO_STATS(mib, basefield, addend)
 193#define __SNMP_UPD_PO_STATS64(mib, basefield, addend) __SNMP_UPD_PO_STATS(mib, basefield, addend)
 194#endif
 195
 196#endif
 197