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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 |
26 | static struct tc_action_ops act_sample_ops; |
27 | ||
28 | static 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 | ||
35 | static 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 |
120 | put_chain: |
121 | if (goto_ch) | |
122 | tcf_chain_put_by_act(goto_ch); | |
123 | release_idr: | |
124 | tcf_idr_release(*a, bind); | |
125 | return err; | |
5c5670fa YG |
126 | } |
127 | ||
9a63b255 | 128 | static 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 |
140 | static 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 | ||
156 | static 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 */ | |
81895a65 | 171 | if (psample_group && (prandom_u32_max(s->rate) == 0)) { |
5c5670fa | 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 |
193 | static 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 |
203 | static 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 | ||
237 | nla_put_failure: | |
653cd284 | 238 | spin_unlock_bh(&s->tcf_lock); |
5c5670fa YG |
239 | nlmsg_trim(skb, b); |
240 | return -1; | |
241 | } | |
242 | ||
4a5da47d VB |
243 | static void tcf_psample_group_put(void *priv) |
244 | { | |
245 | struct psample_group *group = priv; | |
246 | ||
247 | psample_group_put(group); | |
248 | } | |
249 | ||
250 | static struct psample_group * | |
251 | tcf_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 |
267 | static 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 | ||
275 | static 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 |
297 | static 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 | ||
311 | static __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 | 318 | static 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 | ||
323 | static 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 | ||
330 | static int __init sample_init_module(void) | |
331 | { | |
332 | return tcf_register_action(&act_sample_ops, &sample_net_ops); | |
333 | } | |
334 | ||
335 | static void __exit sample_cleanup_module(void) | |
336 | { | |
337 | tcf_unregister_action(&act_sample_ops, &sample_net_ops); | |
338 | } | |
339 | ||
340 | module_init(sample_init_module); | |
341 | module_exit(sample_cleanup_module); | |
342 | ||
f1fd20c3 | 343 | MODULE_AUTHOR("Yotam Gigi <yotam.gi@gmail.com>"); |
5c5670fa YG |
344 | MODULE_DESCRIPTION("Packet sampling action"); |
345 | MODULE_LICENSE("GPL v2"); |