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  */
  29 struct 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
  51 struct 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
  59 struct icmp_mib {
  60         unsigned long   mibs[ICMP_MIB_MAX];
  61 };
  62
  63 #define ICMPMSG_MIB_MAX __ICMPMSG_MIB_MAX
  64 struct 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 */
  71 struct icmpv6_mib {
  72         unsigned long   mibs[ICMP6_MIB_MAX];
  73 };
  74 /* per device counters, (shared on all cpus) */
  75 struct 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 */
  81 struct icmpv6msg_mib {
  82         atomic_long_t   mibs[ICMP6MSG_MIB_MAX];
  83 };
  84 /* per device counters, (shared on all cpus) */
  85 struct icmpv6msg_mib_device {
  86         atomic_long_t   mibs[ICMP6MSG_MIB_MAX];
  87 };
  88
  89
  90 /* TCP */
  91 #define TCP_MIB_MAX     __TCP_MIB_MAX
  92 struct tcp_mib {
  93         unsigned long   mibs[TCP_MIB_MAX];
  94 };
  95
  96 /* UDP */
  97 #define UDP_MIB_MAX     __UDP_MIB_MAX
  98 struct udp_mib {
  99         unsigned long   mibs[UDP_MIB_MAX];
 100 };
 101
 102 /* Linux */
 103 #define LINUX_MIB_MAX   __LINUX_MIB_MAX
 104 struct linux_mib {
 105         unsigned long   mibs[LINUX_MIB_MAX];
 106 };
 107
 108 /* Linux Xfrm */
 109 #define LINUX_MIB_XFRMMAX       __LINUX_MIB_XFRMMAX
 110 struct 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