v4.19.13 snapshot.
diff --git a/include/net/snmp.h b/include/net/snmp.h
new file mode 100644
index 0000000..c9228ad
--- /dev/null
+++ b/include/net/snmp.h
@@ -0,0 +1,201 @@
+/*
+ *
+ * SNMP MIB entries for the IP subsystem.
+ *
+ * Alan Cox <gw4pts@gw4pts.ampr.org>
+ *
+ * We don't chose to implement SNMP in the kernel (this would
+ * be silly as SNMP is a pain in the backside in places). We do
+ * however need to collect the MIB statistics and export them
+ * out of /proc (eventually)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ *
+ */
+
+#ifndef _SNMP_H
+#define _SNMP_H
+
+#include <linux/cache.h>
+#include <linux/snmp.h>
+#include <linux/smp.h>
+
+/*
+ * Mibs are stored in array of unsigned long.
+ */
+/*
+ * struct snmp_mib{}
+ * - list of entries for particular API (such as /proc/net/snmp)
+ * - name of entries.
+ */
+struct snmp_mib {
+ const char *name;
+ int entry;
+};
+
+#define SNMP_MIB_ITEM(_name,_entry) { \
+ .name = _name, \
+ .entry = _entry, \
+}
+
+#define SNMP_MIB_SENTINEL { \
+ .name = NULL, \
+ .entry = 0, \
+}
+
+/*
+ * We use unsigned longs for most mibs but u64 for ipstats.
+ */
+#include <linux/u64_stats_sync.h>
+
+/* IPstats */
+#define IPSTATS_MIB_MAX __IPSTATS_MIB_MAX
+struct ipstats_mib {
+ /* mibs[] must be first field of struct ipstats_mib */
+ u64 mibs[IPSTATS_MIB_MAX];
+ struct u64_stats_sync syncp;
+};
+
+/* ICMP */
+#define ICMP_MIB_MAX __ICMP_MIB_MAX
+struct icmp_mib {
+ unsigned long mibs[ICMP_MIB_MAX];
+};
+
+#define ICMPMSG_MIB_MAX __ICMPMSG_MIB_MAX
+struct icmpmsg_mib {
+ atomic_long_t mibs[ICMPMSG_MIB_MAX];
+};
+
+/* ICMP6 (IPv6-ICMP) */
+#define ICMP6_MIB_MAX __ICMP6_MIB_MAX
+/* per network ns counters */
+struct icmpv6_mib {
+ unsigned long mibs[ICMP6_MIB_MAX];
+};
+/* per device counters, (shared on all cpus) */
+struct icmpv6_mib_device {
+ atomic_long_t mibs[ICMP6_MIB_MAX];
+};
+
+#define ICMP6MSG_MIB_MAX __ICMP6MSG_MIB_MAX
+/* per network ns counters */
+struct icmpv6msg_mib {
+ atomic_long_t mibs[ICMP6MSG_MIB_MAX];
+};
+/* per device counters, (shared on all cpus) */
+struct icmpv6msg_mib_device {
+ atomic_long_t mibs[ICMP6MSG_MIB_MAX];
+};
+
+
+/* TCP */
+#define TCP_MIB_MAX __TCP_MIB_MAX
+struct tcp_mib {
+ unsigned long mibs[TCP_MIB_MAX];
+};
+
+/* UDP */
+#define UDP_MIB_MAX __UDP_MIB_MAX
+struct udp_mib {
+ unsigned long mibs[UDP_MIB_MAX];
+};
+
+/* Linux */
+#define LINUX_MIB_MAX __LINUX_MIB_MAX
+struct linux_mib {
+ unsigned long mibs[LINUX_MIB_MAX];
+};
+
+/* Linux Xfrm */
+#define LINUX_MIB_XFRMMAX __LINUX_MIB_XFRMMAX
+struct linux_xfrm_mib {
+ unsigned long mibs[LINUX_MIB_XFRMMAX];
+};
+
+#define DEFINE_SNMP_STAT(type, name) \
+ __typeof__(type) __percpu *name
+#define DEFINE_SNMP_STAT_ATOMIC(type, name) \
+ __typeof__(type) *name
+#define DECLARE_SNMP_STAT(type, name) \
+ extern __typeof__(type) __percpu *name
+
+#define __SNMP_INC_STATS(mib, field) \
+ __this_cpu_inc(mib->mibs[field])
+
+#define SNMP_INC_STATS_ATOMIC_LONG(mib, field) \
+ atomic_long_inc(&mib->mibs[field])
+
+#define SNMP_INC_STATS(mib, field) \
+ this_cpu_inc(mib->mibs[field])
+
+#define SNMP_DEC_STATS(mib, field) \
+ this_cpu_dec(mib->mibs[field])
+
+#define __SNMP_ADD_STATS(mib, field, addend) \
+ __this_cpu_add(mib->mibs[field], addend)
+
+#define SNMP_ADD_STATS(mib, field, addend) \
+ this_cpu_add(mib->mibs[field], addend)
+#define SNMP_UPD_PO_STATS(mib, basefield, addend) \
+ do { \
+ __typeof__((mib->mibs) + 0) ptr = mib->mibs; \
+ this_cpu_inc(ptr[basefield##PKTS]); \
+ this_cpu_add(ptr[basefield##OCTETS], addend); \
+ } while (0)
+#define __SNMP_UPD_PO_STATS(mib, basefield, addend) \
+ do { \
+ __typeof__((mib->mibs) + 0) ptr = mib->mibs; \
+ __this_cpu_inc(ptr[basefield##PKTS]); \
+ __this_cpu_add(ptr[basefield##OCTETS], addend); \
+ } while (0)
+
+
+#if BITS_PER_LONG==32
+
+#define __SNMP_ADD_STATS64(mib, field, addend) \
+ do { \
+ __typeof__(*mib) *ptr = raw_cpu_ptr(mib); \
+ u64_stats_update_begin(&ptr->syncp); \
+ ptr->mibs[field] += addend; \
+ u64_stats_update_end(&ptr->syncp); \
+ } while (0)
+
+#define SNMP_ADD_STATS64(mib, field, addend) \
+ do { \
+ local_bh_disable(); \
+ __SNMP_ADD_STATS64(mib, field, addend); \
+ local_bh_enable(); \
+ } while (0)
+
+#define __SNMP_INC_STATS64(mib, field) SNMP_ADD_STATS64(mib, field, 1)
+#define SNMP_INC_STATS64(mib, field) SNMP_ADD_STATS64(mib, field, 1)
+#define __SNMP_UPD_PO_STATS64(mib, basefield, addend) \
+ do { \
+ __typeof__(*mib) *ptr; \
+ ptr = raw_cpu_ptr((mib)); \
+ u64_stats_update_begin(&ptr->syncp); \
+ ptr->mibs[basefield##PKTS]++; \
+ ptr->mibs[basefield##OCTETS] += addend; \
+ u64_stats_update_end(&ptr->syncp); \
+ } while (0)
+#define SNMP_UPD_PO_STATS64(mib, basefield, addend) \
+ do { \
+ local_bh_disable(); \
+ __SNMP_UPD_PO_STATS64(mib, basefield, addend); \
+ local_bh_enable(); \
+ } while (0)
+#else
+#define __SNMP_INC_STATS64(mib, field) __SNMP_INC_STATS(mib, field)
+#define SNMP_INC_STATS64(mib, field) SNMP_INC_STATS(mib, field)
+#define SNMP_DEC_STATS64(mib, field) SNMP_DEC_STATS(mib, field)
+#define __SNMP_ADD_STATS64(mib, field, addend) __SNMP_ADD_STATS(mib, field, addend)
+#define SNMP_ADD_STATS64(mib, field, addend) SNMP_ADD_STATS(mib, field, addend)
+#define SNMP_UPD_PO_STATS64(mib, basefield, addend) SNMP_UPD_PO_STATS(mib, basefield, addend)
+#define __SNMP_UPD_PO_STATS64(mib, basefield, addend) __SNMP_UPD_PO_STATS(mib, basefield, addend)
+#endif
+
+#endif