xref: /openbmc/linux/net/sched/cls_matchall.c (revision bfe655d1)
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_call(block, TC_SETUP_CLSMATCHALL, &cls_mall, false);
79 	tcf_block_offload_dec(block, &head->flags);
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);
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_call(block, TC_SETUP_CLSMATCHALL, &cls_mall, skip_sw);
113 	kfree(cls_mall.rule);
114 
115 	if (err < 0) {
116 		mall_destroy_hw_filter(tp, head, cookie, NULL);
117 		return err;
118 	} else if (err > 0) {
119 		head->in_hw_count = err;
120 		tcf_block_offload_inc(block, &head->flags);
121 	}
122 
123 	if (skip_sw && !(head->flags & TCA_CLS_FLAGS_IN_HW))
124 		return -EINVAL;
125 
126 	return 0;
127 }
128 
129 static void mall_destroy(struct tcf_proto *tp, bool rtnl_held,
130 			 struct netlink_ext_ack *extack)
131 {
132 	struct cls_mall_head *head = rtnl_dereference(tp->root);
133 
134 	if (!head)
135 		return;
136 
137 	tcf_unbind_filter(tp, &head->res);
138 
139 	if (!tc_skip_hw(head->flags))
140 		mall_destroy_hw_filter(tp, head, (unsigned long) head, extack);
141 
142 	if (tcf_exts_get_net(&head->exts))
143 		tcf_queue_work(&head->rwork, mall_destroy_work);
144 	else
145 		__mall_destroy(head);
146 }
147 
148 static void *mall_get(struct tcf_proto *tp, u32 handle)
149 {
150 	struct cls_mall_head *head = rtnl_dereference(tp->root);
151 
152 	if (head && head->handle == handle)
153 		return head;
154 
155 	return NULL;
156 }
157 
158 static const struct nla_policy mall_policy[TCA_MATCHALL_MAX + 1] = {
159 	[TCA_MATCHALL_UNSPEC]		= { .type = NLA_UNSPEC },
160 	[TCA_MATCHALL_CLASSID]		= { .type = NLA_U32 },
161 };
162 
163 static int mall_set_parms(struct net *net, struct tcf_proto *tp,
164 			  struct cls_mall_head *head,
165 			  unsigned long base, struct nlattr **tb,
166 			  struct nlattr *est, bool ovr,
167 			  struct netlink_ext_ack *extack)
168 {
169 	int err;
170 
171 	err = tcf_exts_validate(net, tp, tb, est, &head->exts, ovr, true,
172 				extack);
173 	if (err < 0)
174 		return err;
175 
176 	if (tb[TCA_MATCHALL_CLASSID]) {
177 		head->res.classid = nla_get_u32(tb[TCA_MATCHALL_CLASSID]);
178 		tcf_bind_filter(tp, &head->res, base);
179 	}
180 	return 0;
181 }
182 
183 static int mall_change(struct net *net, struct sk_buff *in_skb,
184 		       struct tcf_proto *tp, unsigned long base,
185 		       u32 handle, struct nlattr **tca,
186 		       void **arg, bool ovr, bool rtnl_held,
187 		       struct netlink_ext_ack *extack)
188 {
189 	struct cls_mall_head *head = rtnl_dereference(tp->root);
190 	struct nlattr *tb[TCA_MATCHALL_MAX + 1];
191 	struct cls_mall_head *new;
192 	u32 flags = 0;
193 	int err;
194 
195 	if (!tca[TCA_OPTIONS])
196 		return -EINVAL;
197 
198 	if (head)
199 		return -EEXIST;
200 
201 	err = nla_parse_nested_deprecated(tb, TCA_MATCHALL_MAX,
202 					  tca[TCA_OPTIONS], mall_policy, NULL);
203 	if (err < 0)
204 		return err;
205 
206 	if (tb[TCA_MATCHALL_FLAGS]) {
207 		flags = nla_get_u32(tb[TCA_MATCHALL_FLAGS]);
208 		if (!tc_flags_valid(flags))
209 			return -EINVAL;
210 	}
211 
212 	new = kzalloc(sizeof(*new), GFP_KERNEL);
213 	if (!new)
214 		return -ENOBUFS;
215 
216 	err = tcf_exts_init(&new->exts, net, TCA_MATCHALL_ACT, 0);
217 	if (err)
218 		goto err_exts_init;
219 
220 	if (!handle)
221 		handle = 1;
222 	new->handle = handle;
223 	new->flags = flags;
224 	new->pf = alloc_percpu(struct tc_matchall_pcnt);
225 	if (!new->pf) {
226 		err = -ENOMEM;
227 		goto err_alloc_percpu;
228 	}
229 
230 	err = mall_set_parms(net, tp, new, base, tb, tca[TCA_RATE], ovr,
231 			     extack);
232 	if (err)
233 		goto err_set_parms;
234 
235 	if (!tc_skip_hw(new->flags)) {
236 		err = mall_replace_hw_filter(tp, new, (unsigned long)new,
237 					     extack);
238 		if (err)
239 			goto err_replace_hw_filter;
240 	}
241 
242 	if (!tc_in_hw(new->flags))
243 		new->flags |= TCA_CLS_FLAGS_NOT_IN_HW;
244 
245 	*arg = head;
246 	rcu_assign_pointer(tp->root, new);
247 	return 0;
248 
249 err_replace_hw_filter:
250 err_set_parms:
251 	free_percpu(new->pf);
252 err_alloc_percpu:
253 	tcf_exts_destroy(&new->exts);
254 err_exts_init:
255 	kfree(new);
256 	return err;
257 }
258 
259 static int mall_delete(struct tcf_proto *tp, void *arg, bool *last,
260 		       bool rtnl_held, struct netlink_ext_ack *extack)
261 {
262 	struct cls_mall_head *head = rtnl_dereference(tp->root);
263 
264 	head->deleting = true;
265 	*last = true;
266 	return 0;
267 }
268 
269 static void mall_walk(struct tcf_proto *tp, struct tcf_walker *arg,
270 		      bool rtnl_held)
271 {
272 	struct cls_mall_head *head = rtnl_dereference(tp->root);
273 
274 	if (arg->count < arg->skip)
275 		goto skip;
276 
277 	if (!head || head->deleting)
278 		return;
279 	if (arg->fn(tp, head, arg) < 0)
280 		arg->stop = 1;
281 skip:
282 	arg->count++;
283 }
284 
285 static int mall_reoffload(struct tcf_proto *tp, bool add, tc_setup_cb_t *cb,
286 			  void *cb_priv, struct netlink_ext_ack *extack)
287 {
288 	struct cls_mall_head *head = rtnl_dereference(tp->root);
289 	struct tc_cls_matchall_offload cls_mall = {};
290 	struct tcf_block *block = tp->chain->block;
291 	int err;
292 
293 	if (tc_skip_hw(head->flags))
294 		return 0;
295 
296 	cls_mall.rule =	flow_rule_alloc(tcf_exts_num_actions(&head->exts));
297 	if (!cls_mall.rule)
298 		return -ENOMEM;
299 
300 	tc_cls_common_offload_init(&cls_mall.common, tp, head->flags, extack);
301 	cls_mall.command = add ?
302 		TC_CLSMATCHALL_REPLACE : TC_CLSMATCHALL_DESTROY;
303 	cls_mall.cookie = (unsigned long)head;
304 
305 	err = tc_setup_flow_action(&cls_mall.rule->action, &head->exts);
306 	if (err) {
307 		kfree(cls_mall.rule);
308 		if (add && tc_skip_sw(head->flags)) {
309 			NL_SET_ERR_MSG_MOD(extack, "Failed to setup flow action");
310 			return err;
311 		}
312 		return 0;
313 	}
314 
315 	err = cb(TC_SETUP_CLSMATCHALL, &cls_mall, cb_priv);
316 	kfree(cls_mall.rule);
317 
318 	if (err) {
319 		if (add && tc_skip_sw(head->flags))
320 			return err;
321 		return 0;
322 	}
323 
324 	tc_cls_offload_cnt_update(block, &head->in_hw_count, &head->flags, add);
325 
326 	return 0;
327 }
328 
329 static void mall_stats_hw_filter(struct tcf_proto *tp,
330 				 struct cls_mall_head *head,
331 				 unsigned long cookie)
332 {
333 	struct tc_cls_matchall_offload cls_mall = {};
334 	struct tcf_block *block = tp->chain->block;
335 
336 	tc_cls_common_offload_init(&cls_mall.common, tp, head->flags, NULL);
337 	cls_mall.command = TC_CLSMATCHALL_STATS;
338 	cls_mall.cookie = cookie;
339 
340 	tc_setup_cb_call(block, TC_SETUP_CLSMATCHALL, &cls_mall, false);
341 
342 	tcf_exts_stats_update(&head->exts, cls_mall.stats.bytes,
343 			      cls_mall.stats.pkts, cls_mall.stats.lastused);
344 }
345 
346 static int mall_dump(struct net *net, struct tcf_proto *tp, void *fh,
347 		     struct sk_buff *skb, struct tcmsg *t, bool rtnl_held)
348 {
349 	struct tc_matchall_pcnt gpf = {};
350 	struct cls_mall_head *head = fh;
351 	struct nlattr *nest;
352 	int cpu;
353 
354 	if (!head)
355 		return skb->len;
356 
357 	if (!tc_skip_hw(head->flags))
358 		mall_stats_hw_filter(tp, head, (unsigned long)head);
359 
360 	t->tcm_handle = head->handle;
361 
362 	nest = nla_nest_start_noflag(skb, TCA_OPTIONS);
363 	if (!nest)
364 		goto nla_put_failure;
365 
366 	if (head->res.classid &&
367 	    nla_put_u32(skb, TCA_MATCHALL_CLASSID, head->res.classid))
368 		goto nla_put_failure;
369 
370 	if (head->flags && nla_put_u32(skb, TCA_MATCHALL_FLAGS, head->flags))
371 		goto nla_put_failure;
372 
373 	for_each_possible_cpu(cpu) {
374 		struct tc_matchall_pcnt *pf = per_cpu_ptr(head->pf, cpu);
375 
376 		gpf.rhit += pf->rhit;
377 	}
378 
379 	if (nla_put_64bit(skb, TCA_MATCHALL_PCNT,
380 			  sizeof(struct tc_matchall_pcnt),
381 			  &gpf, TCA_MATCHALL_PAD))
382 		goto nla_put_failure;
383 
384 	if (tcf_exts_dump(skb, &head->exts))
385 		goto nla_put_failure;
386 
387 	nla_nest_end(skb, nest);
388 
389 	if (tcf_exts_dump_stats(skb, &head->exts) < 0)
390 		goto nla_put_failure;
391 
392 	return skb->len;
393 
394 nla_put_failure:
395 	nla_nest_cancel(skb, nest);
396 	return -1;
397 }
398 
399 static void mall_bind_class(void *fh, u32 classid, unsigned long cl)
400 {
401 	struct cls_mall_head *head = fh;
402 
403 	if (head && head->res.classid == classid)
404 		head->res.class = cl;
405 }
406 
407 static struct tcf_proto_ops cls_mall_ops __read_mostly = {
408 	.kind		= "matchall",
409 	.classify	= mall_classify,
410 	.init		= mall_init,
411 	.destroy	= mall_destroy,
412 	.get		= mall_get,
413 	.change		= mall_change,
414 	.delete		= mall_delete,
415 	.walk		= mall_walk,
416 	.reoffload	= mall_reoffload,
417 	.dump		= mall_dump,
418 	.bind_class	= mall_bind_class,
419 	.owner		= THIS_MODULE,
420 };
421 
422 static int __init cls_mall_init(void)
423 {
424 	return register_tcf_proto_ops(&cls_mall_ops);
425 }
426 
427 static void __exit cls_mall_exit(void)
428 {
429 	unregister_tcf_proto_ops(&cls_mall_ops);
430 }
431 
432 module_init(cls_mall_init);
433 module_exit(cls_mall_exit);
434 
435 MODULE_AUTHOR("Jiri Pirko <jiri@mellanox.com>");
436 MODULE_DESCRIPTION("Match-all classifier");
437 MODULE_LICENSE("GPL v2");
438