Merge tag 'dt-for-palmer-v6.1-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git...
[linux-block.git] / net / sched / act_sample.c
CommitLineData
d2912cb1 1// SPDX-License-Identifier: GPL-2.0-only
5c5670fa
YG
2/*
3 * net/sched/act_sample.c - Packet sampling tc action
4 * Copyright (c) 2017 Yotam Gigi <yotamg@mellanox.com>
5c5670fa
YG
5 */
6
7#include <linux/types.h>
8#include <linux/kernel.h>
9#include <linux/string.h>
10#include <linux/errno.h>
11#include <linux/skbuff.h>
12#include <linux/rtnetlink.h>
13#include <linux/module.h>
14#include <linux/init.h>
15#include <linux/gfp.h>
16#include <net/net_namespace.h>
17#include <net/netlink.h>
18#include <net/pkt_sched.h>
19#include <linux/tc_act/tc_sample.h>
20#include <net/tc_act/tc_sample.h>
21#include <net/psample.h>
e8c87c64 22#include <net/pkt_cls.h>
5c5670fa
YG
23
24#include <linux/if_arp.h>
25
5c5670fa
YG
26static struct tc_action_ops act_sample_ops;
27
28static const struct nla_policy sample_policy[TCA_SAMPLE_MAX + 1] = {
29 [TCA_SAMPLE_PARMS] = { .len = sizeof(struct tc_sample) },
30 [TCA_SAMPLE_RATE] = { .type = NLA_U32 },
31 [TCA_SAMPLE_TRUNC_SIZE] = { .type = NLA_U32 },
32 [TCA_SAMPLE_PSAMPLE_GROUP] = { .type = NLA_U32 },
33};
34
35static int tcf_sample_init(struct net *net, struct nlattr *nla,
695176bf
CW
36 struct nlattr *est, struct tc_action **a,
37 struct tcf_proto *tp,
abbb0d33 38 u32 flags, struct netlink_ext_ack *extack)
5c5670fa 39{
acd0a7ab 40 struct tc_action_net *tn = net_generic(net, act_sample_ops.net_id);
695176bf 41 bool bind = flags & TCA_ACT_FLAGS_BIND;
5c5670fa
YG
42 struct nlattr *tb[TCA_SAMPLE_MAX + 1];
43 struct psample_group *psample_group;
7be8ef2c 44 u32 psample_group_num, rate, index;
e8c87c64 45 struct tcf_chain *goto_ch = NULL;
5c5670fa
YG
46 struct tc_sample *parm;
47 struct tcf_sample *s;
48 bool exists = false;
0190c1d4 49 int ret, err;
5c5670fa
YG
50
51 if (!nla)
52 return -EINVAL;
8cb08174
JB
53 ret = nla_parse_nested_deprecated(tb, TCA_SAMPLE_MAX, nla,
54 sample_policy, NULL);
5c5670fa
YG
55 if (ret < 0)
56 return ret;
57 if (!tb[TCA_SAMPLE_PARMS] || !tb[TCA_SAMPLE_RATE] ||
58 !tb[TCA_SAMPLE_PSAMPLE_GROUP])
59 return -EINVAL;
60
61 parm = nla_data(tb[TCA_SAMPLE_PARMS]);
7be8ef2c
DL
62 index = parm->index;
63 err = tcf_idr_check_alloc(tn, &index, a, bind);
0190c1d4
VB
64 if (err < 0)
65 return err;
66 exists = err;
5c5670fa
YG
67 if (exists && bind)
68 return 0;
69
70 if (!exists) {
7be8ef2c 71 ret = tcf_idr_create(tn, index, est, a,
40bd094d 72 &act_sample_ops, bind, true, flags);
0190c1d4 73 if (ret) {
7be8ef2c 74 tcf_idr_cleanup(tn, index);
5c5670fa 75 return ret;
0190c1d4 76 }
5c5670fa 77 ret = ACT_P_CREATED;
695176bf 78 } else if (!(flags & TCA_ACT_FLAGS_REPLACE)) {
65a206c0 79 tcf_idr_release(*a, bind);
4e8ddd7f 80 return -EEXIST;
5c5670fa 81 }
e8c87c64
DC
82 err = tcf_action_check_ctrlact(parm->action, tp, &goto_ch, extack);
83 if (err < 0)
84 goto release_idr;
5c5670fa 85
fae27081
DC
86 rate = nla_get_u32(tb[TCA_SAMPLE_RATE]);
87 if (!rate) {
88 NL_SET_ERR_MSG(extack, "invalid sample rate");
89 err = -EINVAL;
90 goto put_chain;
91 }
653cd284
VB
92 psample_group_num = nla_get_u32(tb[TCA_SAMPLE_PSAMPLE_GROUP]);
93 psample_group = psample_group_get(net, psample_group_num);
cadb9c9f 94 if (!psample_group) {
e8c87c64
DC
95 err = -ENOMEM;
96 goto put_chain;
cadb9c9f 97 }
653cd284
VB
98
99 s = to_sample(*a);
100
101 spin_lock_bh(&s->tcf_lock);
e8c87c64 102 goto_ch = tcf_action_set_ctrlact(*a, parm->action, goto_ch);
fae27081 103 s->rate = rate;
653cd284 104 s->psample_group_num = psample_group_num;
445d3749
PM
105 psample_group = rcu_replace_pointer(s->psample_group, psample_group,
106 lockdep_is_held(&s->tcf_lock));
5c5670fa
YG
107
108 if (tb[TCA_SAMPLE_TRUNC_SIZE]) {
109 s->truncate = true;
110 s->trunc_size = nla_get_u32(tb[TCA_SAMPLE_TRUNC_SIZE]);
111 }
653cd284 112 spin_unlock_bh(&s->tcf_lock);
dbf47a2a
VB
113
114 if (psample_group)
115 psample_group_put(psample_group);
e8c87c64
DC
116 if (goto_ch)
117 tcf_chain_put_by_act(goto_ch);
5c5670fa 118
5c5670fa 119 return ret;
e8c87c64
DC
120put_chain:
121 if (goto_ch)
122 tcf_chain_put_by_act(goto_ch);
123release_idr:
124 tcf_idr_release(*a, bind);
125 return err;
5c5670fa
YG
126}
127
9a63b255 128static void tcf_sample_cleanup(struct tc_action *a)
5c5670fa 129{
90a6ec85 130 struct tcf_sample *s = to_sample(a);
5c5670fa
YG
131 struct psample_group *psample_group;
132
d7728495
VB
133 /* last reference to action, no need to lock */
134 psample_group = rcu_dereference_protected(s->psample_group, 1);
5c5670fa 135 RCU_INIT_POINTER(s->psample_group, NULL);
1f110e7c
DC
136 if (psample_group)
137 psample_group_put(psample_group);
5c5670fa
YG
138}
139
5c5670fa
YG
140static bool tcf_sample_dev_ok_push(struct net_device *dev)
141{
142 switch (dev->type) {
143 case ARPHRD_TUNNEL:
144 case ARPHRD_TUNNEL6:
145 case ARPHRD_SIT:
146 case ARPHRD_IPGRE:
92974a1d 147 case ARPHRD_IP6GRE:
5c5670fa
YG
148 case ARPHRD_VOID:
149 case ARPHRD_NONE:
150 return false;
151 default:
152 return true;
153 }
154}
155
156static int tcf_sample_act(struct sk_buff *skb, const struct tc_action *a,
157 struct tcf_result *res)
158{
159 struct tcf_sample *s = to_sample(a);
160 struct psample_group *psample_group;
a03e99d3 161 struct psample_metadata md = {};
5c5670fa 162 int retval;
5c5670fa
YG
163
164 tcf_lastuse_update(&s->tcf_tm);
50dc9a85 165 bstats_update(this_cpu_ptr(s->common.cpu_bstats), skb);
5c5670fa
YG
166 retval = READ_ONCE(s->tcf_action);
167
7fd4b288 168 psample_group = rcu_dereference_bh(s->psample_group);
5c5670fa
YG
169
170 /* randomly sample packets according to rate */
171 if (psample_group && (prandom_u32() % s->rate == 0)) {
172 if (!skb_at_tc_ingress(skb)) {
a03e99d3
IS
173 md.in_ifindex = skb->skb_iif;
174 md.out_ifindex = skb->dev->ifindex;
5c5670fa 175 } else {
a03e99d3 176 md.in_ifindex = skb->dev->ifindex;
5c5670fa
YG
177 }
178
179 /* on ingress, the mac header gets popped, so push it back */
180 if (skb_at_tc_ingress(skb) && tcf_sample_dev_ok_push(skb->dev))
181 skb_push(skb, skb->mac_len);
182
a03e99d3
IS
183 md.trunc_size = s->truncate ? s->trunc_size : skb->len;
184 psample_sample_packet(psample_group, skb, s->rate, &md);
5c5670fa
YG
185
186 if (skb_at_tc_ingress(skb) && tcf_sample_dev_ok_push(skb->dev))
187 skb_pull(skb, skb->mac_len);
188 }
189
5c5670fa
YG
190 return retval;
191}
192
58c04397
IS
193static void tcf_sample_stats_update(struct tc_action *a, u64 bytes, u64 packets,
194 u64 drops, u64 lastuse, bool hw)
195{
196 struct tcf_sample *s = to_sample(a);
197 struct tcf_t *tm = &s->tcf_tm;
198
199 tcf_action_update_stats(a, bytes, packets, drops, hw);
200 tm->lastuse = max_t(u64, tm->lastuse, lastuse);
201}
202
5c5670fa
YG
203static int tcf_sample_dump(struct sk_buff *skb, struct tc_action *a,
204 int bind, int ref)
205{
206 unsigned char *b = skb_tail_pointer(skb);
207 struct tcf_sample *s = to_sample(a);
208 struct tc_sample opt = {
209 .index = s->tcf_index,
036bb443
VB
210 .refcnt = refcount_read(&s->tcf_refcnt) - ref,
211 .bindcnt = atomic_read(&s->tcf_bindcnt) - bind,
5c5670fa
YG
212 };
213 struct tcf_t t;
214
653cd284 215 spin_lock_bh(&s->tcf_lock);
d7728495 216 opt.action = s->tcf_action;
5c5670fa
YG
217 if (nla_put(skb, TCA_SAMPLE_PARMS, sizeof(opt), &opt))
218 goto nla_put_failure;
219
220 tcf_tm_dump(&t, &s->tcf_tm);
221 if (nla_put_64bit(skb, TCA_SAMPLE_TM, sizeof(t), &t, TCA_SAMPLE_PAD))
222 goto nla_put_failure;
223
224 if (nla_put_u32(skb, TCA_SAMPLE_RATE, s->rate))
225 goto nla_put_failure;
226
227 if (s->truncate)
228 if (nla_put_u32(skb, TCA_SAMPLE_TRUNC_SIZE, s->trunc_size))
229 goto nla_put_failure;
230
231 if (nla_put_u32(skb, TCA_SAMPLE_PSAMPLE_GROUP, s->psample_group_num))
232 goto nla_put_failure;
653cd284 233 spin_unlock_bh(&s->tcf_lock);
d7728495 234
5c5670fa
YG
235 return skb->len;
236
237nla_put_failure:
653cd284 238 spin_unlock_bh(&s->tcf_lock);
5c5670fa
YG
239 nlmsg_trim(skb, b);
240 return -1;
241}
242
4a5da47d
VB
243static void tcf_psample_group_put(void *priv)
244{
245 struct psample_group *group = priv;
246
247 psample_group_put(group);
248}
249
250static struct psample_group *
251tcf_sample_get_group(const struct tc_action *a,
252 tc_action_priv_destructor *destructor)
253{
254 struct tcf_sample *s = to_sample(a);
255 struct psample_group *group;
256
4a5da47d
VB
257 group = rcu_dereference_protected(s->psample_group,
258 lockdep_is_held(&s->tcf_lock));
259 if (group) {
260 psample_group_take(group);
261 *destructor = tcf_psample_group_put;
262 }
4a5da47d
VB
263
264 return group;
265}
266
c54e1d92
BZ
267static void tcf_offload_sample_get_group(struct flow_action_entry *entry,
268 const struct tc_action *act)
269{
270 entry->sample.psample_group =
271 act->ops->get_psample_group(act, &entry->destructor);
272 entry->destructor_priv = entry->sample.psample_group;
273}
274
275static int tcf_sample_offload_act_setup(struct tc_action *act, void *entry_data,
c2ccf84e
IS
276 u32 *index_inc, bool bind,
277 struct netlink_ext_ack *extack)
c54e1d92
BZ
278{
279 if (bind) {
280 struct flow_action_entry *entry = entry_data;
281
282 entry->id = FLOW_ACTION_SAMPLE;
283 entry->sample.trunc_size = tcf_sample_trunc_size(act);
284 entry->sample.truncate = tcf_sample_truncate(act);
285 entry->sample.rate = tcf_sample_rate(act);
286 tcf_offload_sample_get_group(entry, act);
287 *index_inc = 1;
288 } else {
8cbfe939
BZ
289 struct flow_offload_action *fl_action = entry_data;
290
291 fl_action->id = FLOW_ACTION_SAMPLE;
c54e1d92
BZ
292 }
293
294 return 0;
295}
296
5c5670fa
YG
297static struct tc_action_ops act_sample_ops = {
298 .kind = "sample",
eddd2cf1 299 .id = TCA_ID_SAMPLE,
5c5670fa
YG
300 .owner = THIS_MODULE,
301 .act = tcf_sample_act,
58c04397 302 .stats_update = tcf_sample_stats_update,
5c5670fa
YG
303 .dump = tcf_sample_dump,
304 .init = tcf_sample_init,
305 .cleanup = tcf_sample_cleanup,
4a5da47d 306 .get_psample_group = tcf_sample_get_group,
c54e1d92 307 .offload_act_setup = tcf_sample_offload_act_setup,
5c5670fa
YG
308 .size = sizeof(struct tcf_sample),
309};
310
311static __net_init int sample_init_net(struct net *net)
312{
acd0a7ab 313 struct tc_action_net *tn = net_generic(net, act_sample_ops.net_id);
5c5670fa 314
981471bd 315 return tc_action_net_init(net, tn, &act_sample_ops);
5c5670fa
YG
316}
317
039af9c6 318static void __net_exit sample_exit_net(struct list_head *net_list)
5c5670fa 319{
acd0a7ab 320 tc_action_net_exit(net_list, act_sample_ops.net_id);
5c5670fa
YG
321}
322
323static struct pernet_operations sample_net_ops = {
324 .init = sample_init_net,
039af9c6 325 .exit_batch = sample_exit_net,
acd0a7ab 326 .id = &act_sample_ops.net_id,
5c5670fa
YG
327 .size = sizeof(struct tc_action_net),
328};
329
330static int __init sample_init_module(void)
331{
332 return tcf_register_action(&act_sample_ops, &sample_net_ops);
333}
334
335static void __exit sample_cleanup_module(void)
336{
337 tcf_unregister_action(&act_sample_ops, &sample_net_ops);
338}
339
340module_init(sample_init_module);
341module_exit(sample_cleanup_module);
342
f1fd20c3 343MODULE_AUTHOR("Yotam Gigi <yotam.gi@gmail.com>");
5c5670fa
YG
344MODULE_DESCRIPTION("Packet sampling action");
345MODULE_LICENSE("GPL v2");