xref: /linux/net/sched/cls_matchall.c (revision d8e473182ab9e85708067be81d20424045d939fa)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * net/sched/cls_matchll.c		Match-all classifier
4  *
5  * Copyright (c) 2016 Jiri Pirko <jiri@mellanox.com>
6  */
7 
8 #include <linux/kernel.h>
9 #include <linux/init.h>
10 #include <linux/module.h>
11 #include <linux/percpu.h>
12 
13 #include <net/sch_generic.h>
14 #include <net/pkt_cls.h>
15 #include <net/tc_wrapper.h>
16 
17 struct cls_mall_head {
18 	struct tcf_exts exts;
19 	struct tcf_result res;
20 	u32 handle;
21 	u32 flags;
22 	unsigned int in_hw_count;
23 	struct tc_matchall_pcnt __percpu *pf;
24 	struct rcu_work rwork;
25 	bool deleting;
26 };
27 
28 TC_INDIRECT_SCOPE int mall_classify(struct sk_buff *skb,
29 				    const struct tcf_proto *tp,
30 				    struct tcf_result *res)
31 {
32 	struct cls_mall_head *head = rcu_dereference_bh(tp->root);
33 
34 	if (unlikely(!head))
35 		return -1;
36 
37 	if (tc_skip_sw(head->flags))
38 		return -1;
39 
40 	*res = head->res;
41 	__this_cpu_inc(head->pf->rhit);
42 	return tcf_exts_exec(skb, &head->exts, res);
43 }
44 
45 static int mall_init(struct tcf_proto *tp)
46 {
47 	return 0;
48 }
49 
50 static void __mall_destroy(struct cls_mall_head *head)
51 {
52 	tcf_exts_destroy(&head->exts);
53 	tcf_exts_put_net(&head->exts);
54 	free_percpu(head->pf);
55 	kfree(head);
56 }
57 
58 static void mall_destroy_work(struct work_struct *work)
59 {
60 	struct cls_mall_head *head = container_of(to_rcu_work(work),
61 						  struct cls_mall_head,
62 						  rwork);
63 	rtnl_lock();
64 	__mall_destroy(head);
65 	rtnl_unlock();
66 }
67 
68 static void mall_destroy_hw_filter(struct tcf_proto *tp,
69 				   struct cls_mall_head *head,
70 				   unsigned long cookie,
71 				   struct netlink_ext_ack *extack)
72 {
73 	struct tc_cls_matchall_offload cls_mall = {};
74 	struct tcf_block *block = tp->chain->block;
75 
76 	tc_cls_common_offload_init(&cls_mall.common, tp, head->flags, extack);
77 	cls_mall.command = TC_CLSMATCHALL_DESTROY;
78 	cls_mall.cookie = cookie;
79 
80 	tc_setup_cb_destroy(block, tp, TC_SETUP_CLSMATCHALL, &cls_mall, false,
81 			    &head->flags, &head->in_hw_count, true);
82 }
83 
84 static int mall_replace_hw_filter(struct tcf_proto *tp,
85 				  struct cls_mall_head *head,
86 				  unsigned long cookie,
87 				  struct netlink_ext_ack *extack)
88 {
89 	struct tc_cls_matchall_offload cls_mall = {};
90 	struct tcf_block *block = tp->chain->block;
91 	bool skip_sw = tc_skip_sw(head->flags);
92 	int err;
93 
94 	cls_mall.rule =	flow_rule_alloc(tcf_exts_num_actions(&head->exts));
95 	if (!cls_mall.rule)
96 		return -ENOMEM;
97 
98 	tc_cls_common_offload_init(&cls_mall.common, tp, head->flags, extack);
99 	cls_mall.command = TC_CLSMATCHALL_REPLACE;
100 	cls_mall.cookie = cookie;
101 
102 	err = tc_setup_offload_action(&cls_mall.rule->action, &head->exts,
103 				      cls_mall.common.extack);
104 	if (err) {
105 		kfree(cls_mall.rule);
106 		mall_destroy_hw_filter(tp, head, cookie, NULL);
107 
108 		return skip_sw ? err : 0;
109 	}
110 
111 	err = tc_setup_cb_add(block, tp, TC_SETUP_CLSMATCHALL, &cls_mall,
112 			      skip_sw, &head->flags, &head->in_hw_count, true);
113 	tc_cleanup_offload_action(&cls_mall.rule->action);
114 	kfree(cls_mall.rule);
115 
116 	if (err) {
117 		mall_destroy_hw_filter(tp, head, cookie, NULL);
118 		return err;
119 	}
120 
121 	if (skip_sw && !(head->flags & TCA_CLS_FLAGS_IN_HW))
122 		return -EINVAL;
123 
124 	return 0;
125 }
126 
127 static void mall_destroy(struct tcf_proto *tp, bool rtnl_held,
128 			 struct netlink_ext_ack *extack)
129 {
130 	struct cls_mall_head *head = rtnl_dereference(tp->root);
131 
132 	if (!head)
133 		return;
134 
135 	tcf_unbind_filter(tp, &head->res);
136 
137 	if (!tc_skip_hw(head->flags))
138 		mall_destroy_hw_filter(tp, head, (unsigned long) head, extack);
139 
140 	if (tcf_exts_get_net(&head->exts))
141 		tcf_queue_work(&head->rwork, mall_destroy_work);
142 	else
143 		__mall_destroy(head);
144 }
145 
146 static void *mall_get(struct tcf_proto *tp, u32 handle)
147 {
148 	struct cls_mall_head *head = rtnl_dereference(tp->root);
149 
150 	if (head && head->handle == handle)
151 		return head;
152 
153 	return NULL;
154 }
155 
156 static const struct nla_policy mall_policy[TCA_MATCHALL_MAX + 1] = {
157 	[TCA_MATCHALL_UNSPEC]		= { .type = NLA_UNSPEC },
158 	[TCA_MATCHALL_CLASSID]		= { .type = NLA_U32 },
159 	[TCA_MATCHALL_FLAGS]		= { .type = NLA_U32 },
160 };
161 
162 static int mall_set_parms(struct net *net, struct tcf_proto *tp,
163 			  struct cls_mall_head *head,
164 			  unsigned long base, struct nlattr **tb,
165 			  struct nlattr *est, u32 flags, u32 fl_flags,
166 			  struct netlink_ext_ack *extack)
167 {
168 	int err;
169 
170 	err = tcf_exts_validate_ex(net, tp, tb, est, &head->exts, flags,
171 				   fl_flags, extack);
172 	if (err < 0)
173 		return err;
174 
175 	if (tb[TCA_MATCHALL_CLASSID]) {
176 		head->res.classid = nla_get_u32(tb[TCA_MATCHALL_CLASSID]);
177 		tcf_bind_filter(tp, &head->res, base);
178 	}
179 	return 0;
180 }
181 
182 static int mall_change(struct net *net, struct sk_buff *in_skb,
183 		       struct tcf_proto *tp, unsigned long base,
184 		       u32 handle, struct nlattr **tca,
185 		       void **arg, u32 flags,
186 		       struct netlink_ext_ack *extack)
187 {
188 	struct cls_mall_head *head = rtnl_dereference(tp->root);
189 	struct nlattr *tb[TCA_MATCHALL_MAX + 1];
190 	struct cls_mall_head *new;
191 	u32 userflags = 0;
192 	int err;
193 
194 	if (!tca[TCA_OPTIONS])
195 		return -EINVAL;
196 
197 	if (head)
198 		return -EEXIST;
199 
200 	err = nla_parse_nested_deprecated(tb, TCA_MATCHALL_MAX,
201 					  tca[TCA_OPTIONS], mall_policy, NULL);
202 	if (err < 0)
203 		return err;
204 
205 	if (tb[TCA_MATCHALL_FLAGS]) {
206 		userflags = nla_get_u32(tb[TCA_MATCHALL_FLAGS]);
207 		if (!tc_flags_valid(userflags))
208 			return -EINVAL;
209 	}
210 
211 	new = kzalloc(sizeof(*new), GFP_KERNEL);
212 	if (!new)
213 		return -ENOBUFS;
214 
215 	err = tcf_exts_init(&new->exts, net, TCA_MATCHALL_ACT, 0);
216 	if (err)
217 		goto err_exts_init;
218 
219 	if (!handle)
220 		handle = 1;
221 	new->handle = handle;
222 	new->flags = userflags;
223 	new->pf = alloc_percpu(struct tc_matchall_pcnt);
224 	if (!new->pf) {
225 		err = -ENOMEM;
226 		goto err_alloc_percpu;
227 	}
228 
229 	err = mall_set_parms(net, tp, new, base, tb, tca[TCA_RATE],
230 			     flags, new->flags, extack);
231 	if (err)
232 		goto err_set_parms;
233 
234 	if (!tc_skip_hw(new->flags)) {
235 		err = mall_replace_hw_filter(tp, new, (unsigned long)new,
236 					     extack);
237 		if (err)
238 			goto err_replace_hw_filter;
239 	}
240 
241 	if (!tc_in_hw(new->flags))
242 		new->flags |= TCA_CLS_FLAGS_NOT_IN_HW;
243 
244 	*arg = head;
245 	rcu_assign_pointer(tp->root, new);
246 	return 0;
247 
248 err_replace_hw_filter:
249 err_set_parms:
250 	free_percpu(new->pf);
251 err_alloc_percpu:
252 	tcf_exts_destroy(&new->exts);
253 err_exts_init:
254 	kfree(new);
255 	return err;
256 }
257 
258 static int mall_delete(struct tcf_proto *tp, void *arg, bool *last,
259 		       bool rtnl_held, struct netlink_ext_ack *extack)
260 {
261 	struct cls_mall_head *head = rtnl_dereference(tp->root);
262 
263 	head->deleting = true;
264 	*last = true;
265 	return 0;
266 }
267 
268 static void mall_walk(struct tcf_proto *tp, struct tcf_walker *arg,
269 		      bool rtnl_held)
270 {
271 	struct cls_mall_head *head = rtnl_dereference(tp->root);
272 
273 	if (arg->count < arg->skip)
274 		goto skip;
275 
276 	if (!head || head->deleting)
277 		return;
278 	if (arg->fn(tp, head, arg) < 0)
279 		arg->stop = 1;
280 skip:
281 	arg->count++;
282 }
283 
284 static int mall_reoffload(struct tcf_proto *tp, bool add, flow_setup_cb_t *cb,
285 			  void *cb_priv, struct netlink_ext_ack *extack)
286 {
287 	struct cls_mall_head *head = rtnl_dereference(tp->root);
288 	struct tc_cls_matchall_offload cls_mall = {};
289 	struct tcf_block *block = tp->chain->block;
290 	int err;
291 
292 	if (tc_skip_hw(head->flags))
293 		return 0;
294 
295 	cls_mall.rule =	flow_rule_alloc(tcf_exts_num_actions(&head->exts));
296 	if (!cls_mall.rule)
297 		return -ENOMEM;
298 
299 	tc_cls_common_offload_init(&cls_mall.common, tp, head->flags, extack);
300 	cls_mall.command = add ?
301 		TC_CLSMATCHALL_REPLACE : TC_CLSMATCHALL_DESTROY;
302 	cls_mall.cookie = (unsigned long)head;
303 
304 	err = tc_setup_offload_action(&cls_mall.rule->action, &head->exts,
305 				      cls_mall.common.extack);
306 	if (err) {
307 		kfree(cls_mall.rule);
308 
309 		return add && tc_skip_sw(head->flags) ? err : 0;
310 	}
311 
312 	err = tc_setup_cb_reoffload(block, tp, add, cb, TC_SETUP_CLSMATCHALL,
313 				    &cls_mall, cb_priv, &head->flags,
314 				    &head->in_hw_count);
315 	tc_cleanup_offload_action(&cls_mall.rule->action);
316 	kfree(cls_mall.rule);
317 
318 	return err;
319 }
320 
321 static void mall_stats_hw_filter(struct tcf_proto *tp,
322 				 struct cls_mall_head *head,
323 				 unsigned long cookie)
324 {
325 	struct tc_cls_matchall_offload cls_mall = {};
326 	struct tcf_block *block = tp->chain->block;
327 
328 	tc_cls_common_offload_init(&cls_mall.common, tp, head->flags, NULL);
329 	cls_mall.command = TC_CLSMATCHALL_STATS;
330 	cls_mall.cookie = cookie;
331 
332 	tc_setup_cb_call(block, TC_SETUP_CLSMATCHALL, &cls_mall, false, true);
333 
334 	tcf_exts_hw_stats_update(&head->exts, &cls_mall.stats, cls_mall.use_act_stats);
335 }
336 
337 static int mall_dump(struct net *net, struct tcf_proto *tp, void *fh,
338 		     struct sk_buff *skb, struct tcmsg *t, bool rtnl_held)
339 {
340 	struct tc_matchall_pcnt gpf = {};
341 	struct cls_mall_head *head = fh;
342 	struct nlattr *nest;
343 	int cpu;
344 
345 	if (!head)
346 		return skb->len;
347 
348 	if (!tc_skip_hw(head->flags))
349 		mall_stats_hw_filter(tp, head, (unsigned long)head);
350 
351 	t->tcm_handle = head->handle;
352 
353 	nest = nla_nest_start_noflag(skb, TCA_OPTIONS);
354 	if (!nest)
355 		goto nla_put_failure;
356 
357 	if (head->res.classid &&
358 	    nla_put_u32(skb, TCA_MATCHALL_CLASSID, head->res.classid))
359 		goto nla_put_failure;
360 
361 	if (head->flags && nla_put_u32(skb, TCA_MATCHALL_FLAGS, head->flags))
362 		goto nla_put_failure;
363 
364 	for_each_possible_cpu(cpu) {
365 		struct tc_matchall_pcnt *pf = per_cpu_ptr(head->pf, cpu);
366 
367 		gpf.rhit += pf->rhit;
368 	}
369 
370 	if (nla_put_64bit(skb, TCA_MATCHALL_PCNT,
371 			  sizeof(struct tc_matchall_pcnt),
372 			  &gpf, TCA_MATCHALL_PAD))
373 		goto nla_put_failure;
374 
375 	if (tcf_exts_dump(skb, &head->exts))
376 		goto nla_put_failure;
377 
378 	nla_nest_end(skb, nest);
379 
380 	if (tcf_exts_dump_stats(skb, &head->exts) < 0)
381 		goto nla_put_failure;
382 
383 	return skb->len;
384 
385 nla_put_failure:
386 	nla_nest_cancel(skb, nest);
387 	return -1;
388 }
389 
390 static void mall_bind_class(void *fh, u32 classid, unsigned long cl, void *q,
391 			    unsigned long base)
392 {
393 	struct cls_mall_head *head = fh;
394 
395 	tc_cls_bind_class(classid, cl, q, &head->res, base);
396 }
397 
398 static struct tcf_proto_ops cls_mall_ops __read_mostly = {
399 	.kind		= "matchall",
400 	.classify	= mall_classify,
401 	.init		= mall_init,
402 	.destroy	= mall_destroy,
403 	.get		= mall_get,
404 	.change		= mall_change,
405 	.delete		= mall_delete,
406 	.walk		= mall_walk,
407 	.reoffload	= mall_reoffload,
408 	.dump		= mall_dump,
409 	.bind_class	= mall_bind_class,
410 	.owner		= THIS_MODULE,
411 };
412 
413 static int __init cls_mall_init(void)
414 {
415 	return register_tcf_proto_ops(&cls_mall_ops);
416 }
417 
418 static void __exit cls_mall_exit(void)
419 {
420 	unregister_tcf_proto_ops(&cls_mall_ops);
421 }
422 
423 module_init(cls_mall_init);
424 module_exit(cls_mall_exit);
425 
426 MODULE_AUTHOR("Jiri Pirko <jiri@mellanox.com>");
427 MODULE_DESCRIPTION("Match-all classifier");
428 MODULE_LICENSE("GPL v2");
429