xref: /openbmc/linux/net/sched/cls_matchall.c (revision dc6a81c3)
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 
16 struct cls_mall_head {
17 	struct tcf_exts exts;
18 	struct tcf_result res;
19 	u32 handle;
20 	u32 flags;
21 	unsigned int in_hw_count;
22 	struct tc_matchall_pcnt __percpu *pf;
23 	struct rcu_work rwork;
24 	bool deleting;
25 };
26 
27 static int mall_classify(struct sk_buff *skb, const struct tcf_proto *tp,
28 			 struct tcf_result *res)
29 {
30 	struct cls_mall_head *head = rcu_dereference_bh(tp->root);
31 
32 	if (unlikely(!head))
33 		return -1;
34 
35 	if (tc_skip_sw(head->flags))
36 		return -1;
37 
38 	*res = head->res;
39 	__this_cpu_inc(head->pf->rhit);
40 	return tcf_exts_exec(skb, &head->exts, res);
41 }
42 
43 static int mall_init(struct tcf_proto *tp)
44 {
45 	return 0;
46 }
47 
48 static void __mall_destroy(struct cls_mall_head *head)
49 {
50 	tcf_exts_destroy(&head->exts);
51 	tcf_exts_put_net(&head->exts);
52 	free_percpu(head->pf);
53 	kfree(head);
54 }
55 
56 static void mall_destroy_work(struct work_struct *work)
57 {
58 	struct cls_mall_head *head = container_of(to_rcu_work(work),
59 						  struct cls_mall_head,
60 						  rwork);
61 	rtnl_lock();
62 	__mall_destroy(head);
63 	rtnl_unlock();
64 }
65 
66 static void mall_destroy_hw_filter(struct tcf_proto *tp,
67 				   struct cls_mall_head *head,
68 				   unsigned long cookie,
69 				   struct netlink_ext_ack *extack)
70 {
71 	struct tc_cls_matchall_offload cls_mall = {};
72 	struct tcf_block *block = tp->chain->block;
73 
74 	tc_cls_common_offload_init(&cls_mall.common, tp, head->flags, extack);
75 	cls_mall.command = TC_CLSMATCHALL_DESTROY;
76 	cls_mall.cookie = cookie;
77 
78 	tc_setup_cb_destroy(block, tp, TC_SETUP_CLSMATCHALL, &cls_mall, false,
79 			    &head->flags, &head->in_hw_count, true);
80 }
81 
82 static int mall_replace_hw_filter(struct tcf_proto *tp,
83 				  struct cls_mall_head *head,
84 				  unsigned long cookie,
85 				  struct netlink_ext_ack *extack)
86 {
87 	struct tc_cls_matchall_offload cls_mall = {};
88 	struct tcf_block *block = tp->chain->block;
89 	bool skip_sw = tc_skip_sw(head->flags);
90 	int err;
91 
92 	cls_mall.rule =	flow_rule_alloc(tcf_exts_num_actions(&head->exts));
93 	if (!cls_mall.rule)
94 		return -ENOMEM;
95 
96 	tc_cls_common_offload_init(&cls_mall.common, tp, head->flags, extack);
97 	cls_mall.command = TC_CLSMATCHALL_REPLACE;
98 	cls_mall.cookie = cookie;
99 
100 	err = tc_setup_flow_action(&cls_mall.rule->action, &head->exts, true);
101 	if (err) {
102 		kfree(cls_mall.rule);
103 		mall_destroy_hw_filter(tp, head, cookie, NULL);
104 		if (skip_sw)
105 			NL_SET_ERR_MSG_MOD(extack, "Failed to setup flow action");
106 		else
107 			err = 0;
108 
109 		return err;
110 	}
111 
112 	err = tc_setup_cb_add(block, tp, TC_SETUP_CLSMATCHALL, &cls_mall,
113 			      skip_sw, &head->flags, &head->in_hw_count, true);
114 	tc_cleanup_flow_action(&cls_mall.rule->action);
115 	kfree(cls_mall.rule);
116 
117 	if (err) {
118 		mall_destroy_hw_filter(tp, head, cookie, NULL);
119 		return err;
120 	}
121 
122 	if (skip_sw && !(head->flags & TCA_CLS_FLAGS_IN_HW))
123 		return -EINVAL;
124 
125 	return 0;
126 }
127 
128 static void mall_destroy(struct tcf_proto *tp, bool rtnl_held,
129 			 struct netlink_ext_ack *extack)
130 {
131 	struct cls_mall_head *head = rtnl_dereference(tp->root);
132 
133 	if (!head)
134 		return;
135 
136 	tcf_unbind_filter(tp, &head->res);
137 
138 	if (!tc_skip_hw(head->flags))
139 		mall_destroy_hw_filter(tp, head, (unsigned long) head, extack);
140 
141 	if (tcf_exts_get_net(&head->exts))
142 		tcf_queue_work(&head->rwork, mall_destroy_work);
143 	else
144 		__mall_destroy(head);
145 }
146 
147 static void *mall_get(struct tcf_proto *tp, u32 handle)
148 {
149 	struct cls_mall_head *head = rtnl_dereference(tp->root);
150 
151 	if (head && head->handle == handle)
152 		return head;
153 
154 	return NULL;
155 }
156 
157 static const struct nla_policy mall_policy[TCA_MATCHALL_MAX + 1] = {
158 	[TCA_MATCHALL_UNSPEC]		= { .type = NLA_UNSPEC },
159 	[TCA_MATCHALL_CLASSID]		= { .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, bool ovr,
166 			  struct netlink_ext_ack *extack)
167 {
168 	int err;
169 
170 	err = tcf_exts_validate(net, tp, tb, est, &head->exts, ovr, true,
171 				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, bool ovr, bool rtnl_held,
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 flags = 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 		flags = nla_get_u32(tb[TCA_MATCHALL_FLAGS]);
207 		if (!tc_flags_valid(flags))
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 = flags;
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], ovr,
230 			     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_flow_action(&cls_mall.rule->action, &head->exts, true);
305 	if (err) {
306 		kfree(cls_mall.rule);
307 		if (add && tc_skip_sw(head->flags)) {
308 			NL_SET_ERR_MSG_MOD(extack, "Failed to setup flow action");
309 			return err;
310 		}
311 		return 0;
312 	}
313 
314 	err = tc_setup_cb_reoffload(block, tp, add, cb, TC_SETUP_CLSMATCHALL,
315 				    &cls_mall, cb_priv, &head->flags,
316 				    &head->in_hw_count);
317 	tc_cleanup_flow_action(&cls_mall.rule->action);
318 	kfree(cls_mall.rule);
319 
320 	if (err)
321 		return err;
322 
323 	return 0;
324 }
325 
326 static void mall_stats_hw_filter(struct tcf_proto *tp,
327 				 struct cls_mall_head *head,
328 				 unsigned long cookie)
329 {
330 	struct tc_cls_matchall_offload cls_mall = {};
331 	struct tcf_block *block = tp->chain->block;
332 
333 	tc_cls_common_offload_init(&cls_mall.common, tp, head->flags, NULL);
334 	cls_mall.command = TC_CLSMATCHALL_STATS;
335 	cls_mall.cookie = cookie;
336 
337 	tc_setup_cb_call(block, TC_SETUP_CLSMATCHALL, &cls_mall, false, true);
338 
339 	tcf_exts_stats_update(&head->exts, cls_mall.stats.bytes,
340 			      cls_mall.stats.pkts, cls_mall.stats.lastused);
341 }
342 
343 static int mall_dump(struct net *net, struct tcf_proto *tp, void *fh,
344 		     struct sk_buff *skb, struct tcmsg *t, bool rtnl_held)
345 {
346 	struct tc_matchall_pcnt gpf = {};
347 	struct cls_mall_head *head = fh;
348 	struct nlattr *nest;
349 	int cpu;
350 
351 	if (!head)
352 		return skb->len;
353 
354 	if (!tc_skip_hw(head->flags))
355 		mall_stats_hw_filter(tp, head, (unsigned long)head);
356 
357 	t->tcm_handle = head->handle;
358 
359 	nest = nla_nest_start_noflag(skb, TCA_OPTIONS);
360 	if (!nest)
361 		goto nla_put_failure;
362 
363 	if (head->res.classid &&
364 	    nla_put_u32(skb, TCA_MATCHALL_CLASSID, head->res.classid))
365 		goto nla_put_failure;
366 
367 	if (head->flags && nla_put_u32(skb, TCA_MATCHALL_FLAGS, head->flags))
368 		goto nla_put_failure;
369 
370 	for_each_possible_cpu(cpu) {
371 		struct tc_matchall_pcnt *pf = per_cpu_ptr(head->pf, cpu);
372 
373 		gpf.rhit += pf->rhit;
374 	}
375 
376 	if (nla_put_64bit(skb, TCA_MATCHALL_PCNT,
377 			  sizeof(struct tc_matchall_pcnt),
378 			  &gpf, TCA_MATCHALL_PAD))
379 		goto nla_put_failure;
380 
381 	if (tcf_exts_dump(skb, &head->exts))
382 		goto nla_put_failure;
383 
384 	nla_nest_end(skb, nest);
385 
386 	if (tcf_exts_dump_stats(skb, &head->exts) < 0)
387 		goto nla_put_failure;
388 
389 	return skb->len;
390 
391 nla_put_failure:
392 	nla_nest_cancel(skb, nest);
393 	return -1;
394 }
395 
396 static void mall_bind_class(void *fh, u32 classid, unsigned long cl, void *q,
397 			    unsigned long base)
398 {
399 	struct cls_mall_head *head = fh;
400 
401 	if (head && head->res.classid == classid) {
402 		if (cl)
403 			__tcf_bind_filter(q, &head->res, base);
404 		else
405 			__tcf_unbind_filter(q, &head->res);
406 	}
407 }
408 
409 static struct tcf_proto_ops cls_mall_ops __read_mostly = {
410 	.kind		= "matchall",
411 	.classify	= mall_classify,
412 	.init		= mall_init,
413 	.destroy	= mall_destroy,
414 	.get		= mall_get,
415 	.change		= mall_change,
416 	.delete		= mall_delete,
417 	.walk		= mall_walk,
418 	.reoffload	= mall_reoffload,
419 	.dump		= mall_dump,
420 	.bind_class	= mall_bind_class,
421 	.owner		= THIS_MODULE,
422 };
423 
424 static int __init cls_mall_init(void)
425 {
426 	return register_tcf_proto_ops(&cls_mall_ops);
427 }
428 
429 static void __exit cls_mall_exit(void)
430 {
431 	unregister_tcf_proto_ops(&cls_mall_ops);
432 }
433 
434 module_init(cls_mall_init);
435 module_exit(cls_mall_exit);
436 
437 MODULE_AUTHOR("Jiri Pirko <jiri@mellanox.com>");
438 MODULE_DESCRIPTION("Match-all classifier");
439 MODULE_LICENSE("GPL v2");
440