xref: /linux/net/sched/cls_matchall.c (revision f4738f56d1dc62aaba69b33702a5ab098f1b8c63)
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_change(struct net *net, struct sk_buff *in_skb,
163 		       struct tcf_proto *tp, unsigned long base,
164 		       u32 handle, struct nlattr **tca,
165 		       void **arg, u32 flags,
166 		       struct netlink_ext_ack *extack)
167 {
168 	struct cls_mall_head *head = rtnl_dereference(tp->root);
169 	struct nlattr *tb[TCA_MATCHALL_MAX + 1];
170 	bool bound_to_filter = false;
171 	struct cls_mall_head *new;
172 	u32 userflags = 0;
173 	int err;
174 
175 	if (!tca[TCA_OPTIONS])
176 		return -EINVAL;
177 
178 	if (head)
179 		return -EEXIST;
180 
181 	err = nla_parse_nested_deprecated(tb, TCA_MATCHALL_MAX,
182 					  tca[TCA_OPTIONS], mall_policy, NULL);
183 	if (err < 0)
184 		return err;
185 
186 	if (tb[TCA_MATCHALL_FLAGS]) {
187 		userflags = nla_get_u32(tb[TCA_MATCHALL_FLAGS]);
188 		if (!tc_flags_valid(userflags))
189 			return -EINVAL;
190 	}
191 
192 	new = kzalloc(sizeof(*new), GFP_KERNEL);
193 	if (!new)
194 		return -ENOBUFS;
195 
196 	err = tcf_exts_init(&new->exts, net, TCA_MATCHALL_ACT, 0);
197 	if (err)
198 		goto err_exts_init;
199 
200 	if (!handle)
201 		handle = 1;
202 	new->handle = handle;
203 	new->flags = userflags;
204 	new->pf = alloc_percpu(struct tc_matchall_pcnt);
205 	if (!new->pf) {
206 		err = -ENOMEM;
207 		goto err_alloc_percpu;
208 	}
209 
210 	err = tcf_exts_validate_ex(net, tp, tb, tca[TCA_RATE],
211 				   &new->exts, flags, new->flags, extack);
212 	if (err < 0)
213 		goto err_set_parms;
214 
215 	if (tb[TCA_MATCHALL_CLASSID]) {
216 		new->res.classid = nla_get_u32(tb[TCA_MATCHALL_CLASSID]);
217 		tcf_bind_filter(tp, &new->res, base);
218 		bound_to_filter = true;
219 	}
220 
221 	if (!tc_skip_hw(new->flags)) {
222 		err = mall_replace_hw_filter(tp, new, (unsigned long)new,
223 					     extack);
224 		if (err)
225 			goto err_replace_hw_filter;
226 	}
227 
228 	if (!tc_in_hw(new->flags))
229 		new->flags |= TCA_CLS_FLAGS_NOT_IN_HW;
230 
231 	*arg = head;
232 	rcu_assign_pointer(tp->root, new);
233 	return 0;
234 
235 err_replace_hw_filter:
236 	if (bound_to_filter)
237 		tcf_unbind_filter(tp, &new->res);
238 err_set_parms:
239 	free_percpu(new->pf);
240 err_alloc_percpu:
241 	tcf_exts_destroy(&new->exts);
242 err_exts_init:
243 	kfree(new);
244 	return err;
245 }
246 
247 static int mall_delete(struct tcf_proto *tp, void *arg, bool *last,
248 		       bool rtnl_held, struct netlink_ext_ack *extack)
249 {
250 	struct cls_mall_head *head = rtnl_dereference(tp->root);
251 
252 	head->deleting = true;
253 	*last = true;
254 	return 0;
255 }
256 
257 static void mall_walk(struct tcf_proto *tp, struct tcf_walker *arg,
258 		      bool rtnl_held)
259 {
260 	struct cls_mall_head *head = rtnl_dereference(tp->root);
261 
262 	if (arg->count < arg->skip)
263 		goto skip;
264 
265 	if (!head || head->deleting)
266 		return;
267 	if (arg->fn(tp, head, arg) < 0)
268 		arg->stop = 1;
269 skip:
270 	arg->count++;
271 }
272 
273 static int mall_reoffload(struct tcf_proto *tp, bool add, flow_setup_cb_t *cb,
274 			  void *cb_priv, struct netlink_ext_ack *extack)
275 {
276 	struct cls_mall_head *head = rtnl_dereference(tp->root);
277 	struct tc_cls_matchall_offload cls_mall = {};
278 	struct tcf_block *block = tp->chain->block;
279 	int err;
280 
281 	if (tc_skip_hw(head->flags))
282 		return 0;
283 
284 	cls_mall.rule =	flow_rule_alloc(tcf_exts_num_actions(&head->exts));
285 	if (!cls_mall.rule)
286 		return -ENOMEM;
287 
288 	tc_cls_common_offload_init(&cls_mall.common, tp, head->flags, extack);
289 	cls_mall.command = add ?
290 		TC_CLSMATCHALL_REPLACE : TC_CLSMATCHALL_DESTROY;
291 	cls_mall.cookie = (unsigned long)head;
292 
293 	err = tc_setup_offload_action(&cls_mall.rule->action, &head->exts,
294 				      cls_mall.common.extack);
295 	if (err) {
296 		kfree(cls_mall.rule);
297 
298 		return add && tc_skip_sw(head->flags) ? err : 0;
299 	}
300 
301 	err = tc_setup_cb_reoffload(block, tp, add, cb, TC_SETUP_CLSMATCHALL,
302 				    &cls_mall, cb_priv, &head->flags,
303 				    &head->in_hw_count);
304 	tc_cleanup_offload_action(&cls_mall.rule->action);
305 	kfree(cls_mall.rule);
306 
307 	return err;
308 }
309 
310 static void mall_stats_hw_filter(struct tcf_proto *tp,
311 				 struct cls_mall_head *head,
312 				 unsigned long cookie)
313 {
314 	struct tc_cls_matchall_offload cls_mall = {};
315 	struct tcf_block *block = tp->chain->block;
316 
317 	tc_cls_common_offload_init(&cls_mall.common, tp, head->flags, NULL);
318 	cls_mall.command = TC_CLSMATCHALL_STATS;
319 	cls_mall.cookie = cookie;
320 
321 	tc_setup_cb_call(block, TC_SETUP_CLSMATCHALL, &cls_mall, false, true);
322 
323 	tcf_exts_hw_stats_update(&head->exts, &cls_mall.stats, cls_mall.use_act_stats);
324 }
325 
326 static int mall_dump(struct net *net, struct tcf_proto *tp, void *fh,
327 		     struct sk_buff *skb, struct tcmsg *t, bool rtnl_held)
328 {
329 	struct tc_matchall_pcnt gpf = {};
330 	struct cls_mall_head *head = fh;
331 	struct nlattr *nest;
332 	int cpu;
333 
334 	if (!head)
335 		return skb->len;
336 
337 	if (!tc_skip_hw(head->flags))
338 		mall_stats_hw_filter(tp, head, (unsigned long)head);
339 
340 	t->tcm_handle = head->handle;
341 
342 	nest = nla_nest_start_noflag(skb, TCA_OPTIONS);
343 	if (!nest)
344 		goto nla_put_failure;
345 
346 	if (head->res.classid &&
347 	    nla_put_u32(skb, TCA_MATCHALL_CLASSID, head->res.classid))
348 		goto nla_put_failure;
349 
350 	if (head->flags && nla_put_u32(skb, TCA_MATCHALL_FLAGS, head->flags))
351 		goto nla_put_failure;
352 
353 	for_each_possible_cpu(cpu) {
354 		struct tc_matchall_pcnt *pf = per_cpu_ptr(head->pf, cpu);
355 
356 		gpf.rhit += pf->rhit;
357 	}
358 
359 	if (nla_put_64bit(skb, TCA_MATCHALL_PCNT,
360 			  sizeof(struct tc_matchall_pcnt),
361 			  &gpf, TCA_MATCHALL_PAD))
362 		goto nla_put_failure;
363 
364 	if (tcf_exts_dump(skb, &head->exts))
365 		goto nla_put_failure;
366 
367 	nla_nest_end(skb, nest);
368 
369 	if (tcf_exts_dump_stats(skb, &head->exts) < 0)
370 		goto nla_put_failure;
371 
372 	return skb->len;
373 
374 nla_put_failure:
375 	nla_nest_cancel(skb, nest);
376 	return -1;
377 }
378 
379 static void mall_bind_class(void *fh, u32 classid, unsigned long cl, void *q,
380 			    unsigned long base)
381 {
382 	struct cls_mall_head *head = fh;
383 
384 	tc_cls_bind_class(classid, cl, q, &head->res, base);
385 }
386 
387 static struct tcf_proto_ops cls_mall_ops __read_mostly = {
388 	.kind		= "matchall",
389 	.classify	= mall_classify,
390 	.init		= mall_init,
391 	.destroy	= mall_destroy,
392 	.get		= mall_get,
393 	.change		= mall_change,
394 	.delete		= mall_delete,
395 	.walk		= mall_walk,
396 	.reoffload	= mall_reoffload,
397 	.dump		= mall_dump,
398 	.bind_class	= mall_bind_class,
399 	.owner		= THIS_MODULE,
400 };
401 
402 static int __init cls_mall_init(void)
403 {
404 	return register_tcf_proto_ops(&cls_mall_ops);
405 }
406 
407 static void __exit cls_mall_exit(void)
408 {
409 	unregister_tcf_proto_ops(&cls_mall_ops);
410 }
411 
412 module_init(cls_mall_init);
413 module_exit(cls_mall_exit);
414 
415 MODULE_AUTHOR("Jiri Pirko <jiri@mellanox.com>");
416 MODULE_DESCRIPTION("Match-all classifier");
417 MODULE_LICENSE("GPL v2");
418