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-rw-r--r--net/sched/act_sample.c274
1 files changed, 274 insertions, 0 deletions
diff --git a/net/sched/act_sample.c b/net/sched/act_sample.c
new file mode 100644
index 000000000000..39229756de07
--- /dev/null
+++ b/net/sched/act_sample.c
@@ -0,0 +1,274 @@
+/*
+ * net/sched/act_sample.c - Packet sampling tc action
+ * Copyright (c) 2017 Yotam Gigi <yotamg@mellanox.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/string.h>
+#include <linux/errno.h>
+#include <linux/skbuff.h>
+#include <linux/rtnetlink.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/gfp.h>
+#include <net/net_namespace.h>
+#include <net/netlink.h>
+#include <net/pkt_sched.h>
+#include <linux/tc_act/tc_sample.h>
+#include <net/tc_act/tc_sample.h>
+#include <net/psample.h>
+
+#include <linux/if_arp.h>
+
+#define SAMPLE_TAB_MASK 7
+static unsigned int sample_net_id;
+static struct tc_action_ops act_sample_ops;
+
+static const struct nla_policy sample_policy[TCA_SAMPLE_MAX + 1] = {
+ [TCA_SAMPLE_PARMS] = { .len = sizeof(struct tc_sample) },
+ [TCA_SAMPLE_RATE] = { .type = NLA_U32 },
+ [TCA_SAMPLE_TRUNC_SIZE] = { .type = NLA_U32 },
+ [TCA_SAMPLE_PSAMPLE_GROUP] = { .type = NLA_U32 },
+};
+
+static int tcf_sample_init(struct net *net, struct nlattr *nla,
+ struct nlattr *est, struct tc_action **a, int ovr,
+ int bind)
+{
+ struct tc_action_net *tn = net_generic(net, sample_net_id);
+ struct nlattr *tb[TCA_SAMPLE_MAX + 1];
+ struct psample_group *psample_group;
+ struct tc_sample *parm;
+ struct tcf_sample *s;
+ bool exists = false;
+ int ret;
+
+ if (!nla)
+ return -EINVAL;
+ ret = nla_parse_nested(tb, TCA_SAMPLE_MAX, nla, sample_policy);
+ if (ret < 0)
+ return ret;
+ if (!tb[TCA_SAMPLE_PARMS] || !tb[TCA_SAMPLE_RATE] ||
+ !tb[TCA_SAMPLE_PSAMPLE_GROUP])
+ return -EINVAL;
+
+ parm = nla_data(tb[TCA_SAMPLE_PARMS]);
+
+ exists = tcf_hash_check(tn, parm->index, a, bind);
+ if (exists && bind)
+ return 0;
+
+ if (!exists) {
+ ret = tcf_hash_create(tn, parm->index, est, a,
+ &act_sample_ops, bind, false);
+ if (ret)
+ return ret;
+ ret = ACT_P_CREATED;
+ } else {
+ tcf_hash_release(*a, bind);
+ if (!ovr)
+ return -EEXIST;
+ }
+ s = to_sample(*a);
+
+ ASSERT_RTNL();
+ s->tcf_action = parm->action;
+ s->rate = nla_get_u32(tb[TCA_SAMPLE_RATE]);
+ s->psample_group_num = nla_get_u32(tb[TCA_SAMPLE_PSAMPLE_GROUP]);
+ psample_group = psample_group_get(net, s->psample_group_num);
+ if (!psample_group)
+ return -ENOMEM;
+ RCU_INIT_POINTER(s->psample_group, psample_group);
+
+ if (tb[TCA_SAMPLE_TRUNC_SIZE]) {
+ s->truncate = true;
+ s->trunc_size = nla_get_u32(tb[TCA_SAMPLE_TRUNC_SIZE]);
+ }
+
+ if (ret == ACT_P_CREATED)
+ tcf_hash_insert(tn, *a);
+ return ret;
+}
+
+static void tcf_sample_cleanup_rcu(struct rcu_head *rcu)
+{
+ struct tcf_sample *s = container_of(rcu, struct tcf_sample, rcu);
+ struct psample_group *psample_group;
+
+ psample_group = rcu_dereference_protected(s->psample_group, 1);
+ RCU_INIT_POINTER(s->psample_group, NULL);
+ psample_group_put(psample_group);
+}
+
+static void tcf_sample_cleanup(struct tc_action *a, int bind)
+{
+ struct tcf_sample *s = to_sample(a);
+
+ call_rcu(&s->rcu, tcf_sample_cleanup_rcu);
+}
+
+static bool tcf_sample_dev_ok_push(struct net_device *dev)
+{
+ switch (dev->type) {
+ case ARPHRD_TUNNEL:
+ case ARPHRD_TUNNEL6:
+ case ARPHRD_SIT:
+ case ARPHRD_IPGRE:
+ case ARPHRD_VOID:
+ case ARPHRD_NONE:
+ return false;
+ default:
+ return true;
+ }
+}
+
+static int tcf_sample_act(struct sk_buff *skb, const struct tc_action *a,
+ struct tcf_result *res)
+{
+ struct tcf_sample *s = to_sample(a);
+ struct psample_group *psample_group;
+ int retval;
+ int size;
+ int iif;
+ int oif;
+
+ tcf_lastuse_update(&s->tcf_tm);
+ bstats_cpu_update(this_cpu_ptr(s->common.cpu_bstats), skb);
+ retval = READ_ONCE(s->tcf_action);
+
+ rcu_read_lock();
+ psample_group = rcu_dereference(s->psample_group);
+
+ /* randomly sample packets according to rate */
+ if (psample_group && (prandom_u32() % s->rate == 0)) {
+ if (!skb_at_tc_ingress(skb)) {
+ iif = skb->skb_iif;
+ oif = skb->dev->ifindex;
+ } else {
+ iif = skb->dev->ifindex;
+ oif = 0;
+ }
+
+ /* on ingress, the mac header gets popped, so push it back */
+ if (skb_at_tc_ingress(skb) && tcf_sample_dev_ok_push(skb->dev))
+ skb_push(skb, skb->mac_len);
+
+ size = s->truncate ? s->trunc_size : skb->len;
+ psample_sample_packet(psample_group, skb, size, iif, oif,
+ s->rate);
+
+ if (skb_at_tc_ingress(skb) && tcf_sample_dev_ok_push(skb->dev))
+ skb_pull(skb, skb->mac_len);
+ }
+
+ rcu_read_unlock();
+ return retval;
+}
+
+static int tcf_sample_dump(struct sk_buff *skb, struct tc_action *a,
+ int bind, int ref)
+{
+ unsigned char *b = skb_tail_pointer(skb);
+ struct tcf_sample *s = to_sample(a);
+ struct tc_sample opt = {
+ .index = s->tcf_index,
+ .action = s->tcf_action,
+ .refcnt = s->tcf_refcnt - ref,
+ .bindcnt = s->tcf_bindcnt - bind,
+ };
+ struct tcf_t t;
+
+ if (nla_put(skb, TCA_SAMPLE_PARMS, sizeof(opt), &opt))
+ goto nla_put_failure;
+
+ tcf_tm_dump(&t, &s->tcf_tm);
+ if (nla_put_64bit(skb, TCA_SAMPLE_TM, sizeof(t), &t, TCA_SAMPLE_PAD))
+ goto nla_put_failure;
+
+ if (nla_put_u32(skb, TCA_SAMPLE_RATE, s->rate))
+ goto nla_put_failure;
+
+ if (s->truncate)
+ if (nla_put_u32(skb, TCA_SAMPLE_TRUNC_SIZE, s->trunc_size))
+ goto nla_put_failure;
+
+ if (nla_put_u32(skb, TCA_SAMPLE_PSAMPLE_GROUP, s->psample_group_num))
+ goto nla_put_failure;
+ return skb->len;
+
+nla_put_failure:
+ nlmsg_trim(skb, b);
+ return -1;
+}
+
+static int tcf_sample_walker(struct net *net, struct sk_buff *skb,
+ struct netlink_callback *cb, int type,
+ const struct tc_action_ops *ops)
+{
+ struct tc_action_net *tn = net_generic(net, sample_net_id);
+
+ return tcf_generic_walker(tn, skb, cb, type, ops);
+}
+
+static int tcf_sample_search(struct net *net, struct tc_action **a, u32 index)
+{
+ struct tc_action_net *tn = net_generic(net, sample_net_id);
+
+ return tcf_hash_search(tn, a, index);
+}
+
+static struct tc_action_ops act_sample_ops = {
+ .kind = "sample",
+ .type = TCA_ACT_SAMPLE,
+ .owner = THIS_MODULE,
+ .act = tcf_sample_act,
+ .dump = tcf_sample_dump,
+ .init = tcf_sample_init,
+ .cleanup = tcf_sample_cleanup,
+ .walk = tcf_sample_walker,
+ .lookup = tcf_sample_search,
+ .size = sizeof(struct tcf_sample),
+};
+
+static __net_init int sample_init_net(struct net *net)
+{
+ struct tc_action_net *tn = net_generic(net, sample_net_id);
+
+ return tc_action_net_init(tn, &act_sample_ops, SAMPLE_TAB_MASK);
+}
+
+static void __net_exit sample_exit_net(struct net *net)
+{
+ struct tc_action_net *tn = net_generic(net, sample_net_id);
+
+ tc_action_net_exit(tn);
+}
+
+static struct pernet_operations sample_net_ops = {
+ .init = sample_init_net,
+ .exit = sample_exit_net,
+ .id = &sample_net_id,
+ .size = sizeof(struct tc_action_net),
+};
+
+static int __init sample_init_module(void)
+{
+ return tcf_register_action(&act_sample_ops, &sample_net_ops);
+}
+
+static void __exit sample_cleanup_module(void)
+{
+ tcf_unregister_action(&act_sample_ops, &sample_net_ops);
+}
+
+module_init(sample_init_module);
+module_exit(sample_cleanup_module);
+
+MODULE_AUTHOR("Yotam Gigi <yotamg@mellanox.com>");
+MODULE_DESCRIPTION("Packet sampling action");
+MODULE_LICENSE("GPL v2");
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-15 02:48:30 +0000