xref: /openbmc/linux/net/sched/cls_matchall.c (revision 9dae47aba0a055f761176d9297371d5bb24289ec)
1 /*
2  * net/sched/cls_matchll.c		Match-all classifier
3  *
4  * Copyright (c) 2016 Jiri Pirko <jiri@mellanox.com>
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; either version 2 of the License, or
9  * (at your option) any later version.
10  */
11 
12 #include <linux/kernel.h>
13 #include <linux/init.h>
14 #include <linux/module.h>
15 
16 #include <net/sch_generic.h>
17 #include <net/pkt_cls.h>
18 
19 struct cls_mall_head {
20 	struct tcf_exts exts;
21 	struct tcf_result res;
22 	u32 handle;
23 	u32 flags;
24 	union {
25 		struct work_struct work;
26 		struct rcu_head	rcu;
27 	};
28 };
29 
30 static int mall_classify(struct sk_buff *skb, const struct tcf_proto *tp,
31 			 struct tcf_result *res)
32 {
33 	struct cls_mall_head *head = rcu_dereference_bh(tp->root);
34 
35 	if (tc_skip_sw(head->flags))
36 		return -1;
37 
38 	*res = head->res;
39 	return tcf_exts_exec(skb, &head->exts, res);
40 }
41 
42 static int mall_init(struct tcf_proto *tp)
43 {
44 	return 0;
45 }
46 
47 static void __mall_destroy(struct cls_mall_head *head)
48 {
49 	tcf_exts_destroy(&head->exts);
50 	tcf_exts_put_net(&head->exts);
51 	kfree(head);
52 }
53 
54 static void mall_destroy_work(struct work_struct *work)
55 {
56 	struct cls_mall_head *head = container_of(work, struct cls_mall_head,
57 						  work);
58 	rtnl_lock();
59 	__mall_destroy(head);
60 	rtnl_unlock();
61 }
62 
63 static void mall_destroy_rcu(struct rcu_head *rcu)
64 {
65 	struct cls_mall_head *head = container_of(rcu, struct cls_mall_head,
66 						  rcu);
67 
68 	INIT_WORK(&head->work, mall_destroy_work);
69 	tcf_queue_work(&head->work);
70 }
71 
72 static void mall_destroy_hw_filter(struct tcf_proto *tp,
73 				   struct cls_mall_head *head,
74 				   unsigned long cookie)
75 {
76 	struct tc_cls_matchall_offload cls_mall = {};
77 	struct tcf_block *block = tp->chain->block;
78 
79 	tc_cls_common_offload_init(&cls_mall.common, tp);
80 	cls_mall.command = TC_CLSMATCHALL_DESTROY;
81 	cls_mall.cookie = cookie;
82 
83 	tc_setup_cb_call(block, NULL, TC_SETUP_CLSMATCHALL, &cls_mall, false);
84 }
85 
86 static int mall_replace_hw_filter(struct tcf_proto *tp,
87 				  struct cls_mall_head *head,
88 				  unsigned long cookie)
89 {
90 	struct tc_cls_matchall_offload cls_mall = {};
91 	struct tcf_block *block = tp->chain->block;
92 	bool skip_sw = tc_skip_sw(head->flags);
93 	int err;
94 
95 	tc_cls_common_offload_init(&cls_mall.common, tp);
96 	cls_mall.command = TC_CLSMATCHALL_REPLACE;
97 	cls_mall.exts = &head->exts;
98 	cls_mall.cookie = cookie;
99 
100 	err = tc_setup_cb_call(block, NULL, TC_SETUP_CLSMATCHALL,
101 			       &cls_mall, skip_sw);
102 	if (err < 0) {
103 		mall_destroy_hw_filter(tp, head, cookie);
104 		return err;
105 	} else if (err > 0) {
106 		head->flags |= TCA_CLS_FLAGS_IN_HW;
107 	}
108 
109 	if (skip_sw && !(head->flags & TCA_CLS_FLAGS_IN_HW))
110 		return -EINVAL;
111 
112 	return 0;
113 }
114 
115 static void mall_destroy(struct tcf_proto *tp)
116 {
117 	struct cls_mall_head *head = rtnl_dereference(tp->root);
118 
119 	if (!head)
120 		return;
121 
122 	if (!tc_skip_hw(head->flags))
123 		mall_destroy_hw_filter(tp, head, (unsigned long) head);
124 
125 	if (tcf_exts_get_net(&head->exts))
126 		call_rcu(&head->rcu, mall_destroy_rcu);
127 	else
128 		__mall_destroy(head);
129 }
130 
131 static void *mall_get(struct tcf_proto *tp, u32 handle)
132 {
133 	return NULL;
134 }
135 
136 static const struct nla_policy mall_policy[TCA_MATCHALL_MAX + 1] = {
137 	[TCA_MATCHALL_UNSPEC]		= { .type = NLA_UNSPEC },
138 	[TCA_MATCHALL_CLASSID]		= { .type = NLA_U32 },
139 };
140 
141 static int mall_set_parms(struct net *net, struct tcf_proto *tp,
142 			  struct cls_mall_head *head,
143 			  unsigned long base, struct nlattr **tb,
144 			  struct nlattr *est, bool ovr)
145 {
146 	int err;
147 
148 	err = tcf_exts_validate(net, tp, tb, est, &head->exts, ovr);
149 	if (err < 0)
150 		return err;
151 
152 	if (tb[TCA_MATCHALL_CLASSID]) {
153 		head->res.classid = nla_get_u32(tb[TCA_MATCHALL_CLASSID]);
154 		tcf_bind_filter(tp, &head->res, base);
155 	}
156 	return 0;
157 }
158 
159 static int mall_change(struct net *net, struct sk_buff *in_skb,
160 		       struct tcf_proto *tp, unsigned long base,
161 		       u32 handle, struct nlattr **tca,
162 		       void **arg, bool ovr)
163 {
164 	struct cls_mall_head *head = rtnl_dereference(tp->root);
165 	struct nlattr *tb[TCA_MATCHALL_MAX + 1];
166 	struct cls_mall_head *new;
167 	u32 flags = 0;
168 	int err;
169 
170 	if (!tca[TCA_OPTIONS])
171 		return -EINVAL;
172 
173 	if (head)
174 		return -EEXIST;
175 
176 	err = nla_parse_nested(tb, TCA_MATCHALL_MAX, tca[TCA_OPTIONS],
177 			       mall_policy, NULL);
178 	if (err < 0)
179 		return err;
180 
181 	if (tb[TCA_MATCHALL_FLAGS]) {
182 		flags = nla_get_u32(tb[TCA_MATCHALL_FLAGS]);
183 		if (!tc_flags_valid(flags))
184 			return -EINVAL;
185 	}
186 
187 	new = kzalloc(sizeof(*new), GFP_KERNEL);
188 	if (!new)
189 		return -ENOBUFS;
190 
191 	err = tcf_exts_init(&new->exts, TCA_MATCHALL_ACT, 0);
192 	if (err)
193 		goto err_exts_init;
194 
195 	if (!handle)
196 		handle = 1;
197 	new->handle = handle;
198 	new->flags = flags;
199 
200 	err = mall_set_parms(net, tp, new, base, tb, tca[TCA_RATE], ovr);
201 	if (err)
202 		goto err_set_parms;
203 
204 	if (!tc_skip_hw(new->flags)) {
205 		err = mall_replace_hw_filter(tp, new, (unsigned long) new);
206 		if (err)
207 			goto err_replace_hw_filter;
208 	}
209 
210 	if (!tc_in_hw(new->flags))
211 		new->flags |= TCA_CLS_FLAGS_NOT_IN_HW;
212 
213 	*arg = head;
214 	rcu_assign_pointer(tp->root, new);
215 	return 0;
216 
217 err_replace_hw_filter:
218 err_set_parms:
219 	tcf_exts_destroy(&new->exts);
220 err_exts_init:
221 	kfree(new);
222 	return err;
223 }
224 
225 static int mall_delete(struct tcf_proto *tp, void *arg, bool *last)
226 {
227 	return -EOPNOTSUPP;
228 }
229 
230 static void mall_walk(struct tcf_proto *tp, struct tcf_walker *arg)
231 {
232 	struct cls_mall_head *head = rtnl_dereference(tp->root);
233 
234 	if (arg->count < arg->skip)
235 		goto skip;
236 	if (arg->fn(tp, head, arg) < 0)
237 		arg->stop = 1;
238 skip:
239 	arg->count++;
240 }
241 
242 static int mall_dump(struct net *net, struct tcf_proto *tp, void *fh,
243 		     struct sk_buff *skb, struct tcmsg *t)
244 {
245 	struct cls_mall_head *head = fh;
246 	struct nlattr *nest;
247 
248 	if (!head)
249 		return skb->len;
250 
251 	t->tcm_handle = head->handle;
252 
253 	nest = nla_nest_start(skb, TCA_OPTIONS);
254 	if (!nest)
255 		goto nla_put_failure;
256 
257 	if (head->res.classid &&
258 	    nla_put_u32(skb, TCA_MATCHALL_CLASSID, head->res.classid))
259 		goto nla_put_failure;
260 
261 	if (head->flags && nla_put_u32(skb, TCA_MATCHALL_FLAGS, head->flags))
262 		goto nla_put_failure;
263 
264 	if (tcf_exts_dump(skb, &head->exts))
265 		goto nla_put_failure;
266 
267 	nla_nest_end(skb, nest);
268 
269 	if (tcf_exts_dump_stats(skb, &head->exts) < 0)
270 		goto nla_put_failure;
271 
272 	return skb->len;
273 
274 nla_put_failure:
275 	nla_nest_cancel(skb, nest);
276 	return -1;
277 }
278 
279 static void mall_bind_class(void *fh, u32 classid, unsigned long cl)
280 {
281 	struct cls_mall_head *head = fh;
282 
283 	if (head && head->res.classid == classid)
284 		head->res.class = cl;
285 }
286 
287 static struct tcf_proto_ops cls_mall_ops __read_mostly = {
288 	.kind		= "matchall",
289 	.classify	= mall_classify,
290 	.init		= mall_init,
291 	.destroy	= mall_destroy,
292 	.get		= mall_get,
293 	.change		= mall_change,
294 	.delete		= mall_delete,
295 	.walk		= mall_walk,
296 	.dump		= mall_dump,
297 	.bind_class	= mall_bind_class,
298 	.owner		= THIS_MODULE,
299 };
300 
301 static int __init cls_mall_init(void)
302 {
303 	return register_tcf_proto_ops(&cls_mall_ops);
304 }
305 
306 static void __exit cls_mall_exit(void)
307 {
308 	unregister_tcf_proto_ops(&cls_mall_ops);
309 }
310 
311 module_init(cls_mall_init);
312 module_exit(cls_mall_exit);
313 
314 MODULE_AUTHOR("Jiri Pirko <jiri@mellanox.com>");
315 MODULE_DESCRIPTION("Match-all classifier");
316 MODULE_LICENSE("GPL v2");
317