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
17struct 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
28TC_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
45static int mall_init(struct tcf_proto *tp)
46{
47	return 0;
48}
49
50static 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
58static 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
68static 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
84static 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
127static 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
146static 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
156static 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
162static 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
235err_replace_hw_filter:
236	if (bound_to_filter)
237		tcf_unbind_filter(tp, &new->res);
238err_set_parms:
239	free_percpu(new->pf);
240err_alloc_percpu:
241	tcf_exts_destroy(&new->exts);
242err_exts_init:
243	kfree(new);
244	return err;
245}
246
247static 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
257static 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;
269skip:
270	arg->count++;
271}
272
273static 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
310static 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
326static 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
374nla_put_failure:
375	nla_nest_cancel(skb, nest);
376	return -1;
377}
378
379static 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
387static 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};
401MODULE_ALIAS_NET_CLS("matchall");
402
403static int __init cls_mall_init(void)
404{
405	return register_tcf_proto_ops(&cls_mall_ops);
406}
407
408static void __exit cls_mall_exit(void)
409{
410	unregister_tcf_proto_ops(&cls_mall_ops);
411}
412
413module_init(cls_mall_init);
414module_exit(cls_mall_exit);
415
416MODULE_AUTHOR("Jiri Pirko <jiri@mellanox.com>");
417MODULE_DESCRIPTION("Match-all classifier");
418MODULE_LICENSE("GPL v2");
419