xref: /openbmc/linux/net/sched/cls_matchall.c (revision 6d99a79c)
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 	unsigned int in_hw_count;
25 	struct rcu_work rwork;
26 };
27 
28 static int mall_classify(struct sk_buff *skb, const struct tcf_proto *tp,
29 			 struct tcf_result *res)
30 {
31 	struct cls_mall_head *head = rcu_dereference_bh(tp->root);
32 
33 	if (tc_skip_sw(head->flags))
34 		return -1;
35 
36 	*res = head->res;
37 	return tcf_exts_exec(skb, &head->exts, res);
38 }
39 
40 static int mall_init(struct tcf_proto *tp)
41 {
42 	return 0;
43 }
44 
45 static void __mall_destroy(struct cls_mall_head *head)
46 {
47 	tcf_exts_destroy(&head->exts);
48 	tcf_exts_put_net(&head->exts);
49 	kfree(head);
50 }
51 
52 static void mall_destroy_work(struct work_struct *work)
53 {
54 	struct cls_mall_head *head = container_of(to_rcu_work(work),
55 						  struct cls_mall_head,
56 						  rwork);
57 	rtnl_lock();
58 	__mall_destroy(head);
59 	rtnl_unlock();
60 }
61 
62 static void mall_destroy_hw_filter(struct tcf_proto *tp,
63 				   struct cls_mall_head *head,
64 				   unsigned long cookie,
65 				   struct netlink_ext_ack *extack)
66 {
67 	struct tc_cls_matchall_offload cls_mall = {};
68 	struct tcf_block *block = tp->chain->block;
69 
70 	tc_cls_common_offload_init(&cls_mall.common, tp, head->flags, extack);
71 	cls_mall.command = TC_CLSMATCHALL_DESTROY;
72 	cls_mall.cookie = cookie;
73 
74 	tc_setup_cb_call(block, NULL, TC_SETUP_CLSMATCHALL, &cls_mall, false);
75 	tcf_block_offload_dec(block, &head->flags);
76 }
77 
78 static int mall_replace_hw_filter(struct tcf_proto *tp,
79 				  struct cls_mall_head *head,
80 				  unsigned long cookie,
81 				  struct netlink_ext_ack *extack)
82 {
83 	struct tc_cls_matchall_offload cls_mall = {};
84 	struct tcf_block *block = tp->chain->block;
85 	bool skip_sw = tc_skip_sw(head->flags);
86 	int err;
87 
88 	tc_cls_common_offload_init(&cls_mall.common, tp, head->flags, extack);
89 	cls_mall.command = TC_CLSMATCHALL_REPLACE;
90 	cls_mall.exts = &head->exts;
91 	cls_mall.cookie = cookie;
92 
93 	err = tc_setup_cb_call(block, NULL, TC_SETUP_CLSMATCHALL,
94 			       &cls_mall, skip_sw);
95 	if (err < 0) {
96 		mall_destroy_hw_filter(tp, head, cookie, NULL);
97 		return err;
98 	} else if (err > 0) {
99 		head->in_hw_count = err;
100 		tcf_block_offload_inc(block, &head->flags);
101 	}
102 
103 	if (skip_sw && !(head->flags & TCA_CLS_FLAGS_IN_HW))
104 		return -EINVAL;
105 
106 	return 0;
107 }
108 
109 static void mall_destroy(struct tcf_proto *tp, struct netlink_ext_ack *extack)
110 {
111 	struct cls_mall_head *head = rtnl_dereference(tp->root);
112 
113 	if (!head)
114 		return;
115 
116 	tcf_unbind_filter(tp, &head->res);
117 
118 	if (!tc_skip_hw(head->flags))
119 		mall_destroy_hw_filter(tp, head, (unsigned long) head, extack);
120 
121 	if (tcf_exts_get_net(&head->exts))
122 		tcf_queue_work(&head->rwork, mall_destroy_work);
123 	else
124 		__mall_destroy(head);
125 }
126 
127 static void *mall_get(struct tcf_proto *tp, u32 handle)
128 {
129 	return NULL;
130 }
131 
132 static const struct nla_policy mall_policy[TCA_MATCHALL_MAX + 1] = {
133 	[TCA_MATCHALL_UNSPEC]		= { .type = NLA_UNSPEC },
134 	[TCA_MATCHALL_CLASSID]		= { .type = NLA_U32 },
135 };
136 
137 static int mall_set_parms(struct net *net, struct tcf_proto *tp,
138 			  struct cls_mall_head *head,
139 			  unsigned long base, struct nlattr **tb,
140 			  struct nlattr *est, bool ovr,
141 			  struct netlink_ext_ack *extack)
142 {
143 	int err;
144 
145 	err = tcf_exts_validate(net, tp, tb, est, &head->exts, ovr, extack);
146 	if (err < 0)
147 		return err;
148 
149 	if (tb[TCA_MATCHALL_CLASSID]) {
150 		head->res.classid = nla_get_u32(tb[TCA_MATCHALL_CLASSID]);
151 		tcf_bind_filter(tp, &head->res, base);
152 	}
153 	return 0;
154 }
155 
156 static int mall_change(struct net *net, struct sk_buff *in_skb,
157 		       struct tcf_proto *tp, unsigned long base,
158 		       u32 handle, struct nlattr **tca,
159 		       void **arg, bool ovr, struct netlink_ext_ack *extack)
160 {
161 	struct cls_mall_head *head = rtnl_dereference(tp->root);
162 	struct nlattr *tb[TCA_MATCHALL_MAX + 1];
163 	struct cls_mall_head *new;
164 	u32 flags = 0;
165 	int err;
166 
167 	if (!tca[TCA_OPTIONS])
168 		return -EINVAL;
169 
170 	if (head)
171 		return -EEXIST;
172 
173 	err = nla_parse_nested(tb, TCA_MATCHALL_MAX, tca[TCA_OPTIONS],
174 			       mall_policy, NULL);
175 	if (err < 0)
176 		return err;
177 
178 	if (tb[TCA_MATCHALL_FLAGS]) {
179 		flags = nla_get_u32(tb[TCA_MATCHALL_FLAGS]);
180 		if (!tc_flags_valid(flags))
181 			return -EINVAL;
182 	}
183 
184 	new = kzalloc(sizeof(*new), GFP_KERNEL);
185 	if (!new)
186 		return -ENOBUFS;
187 
188 	err = tcf_exts_init(&new->exts, TCA_MATCHALL_ACT, 0);
189 	if (err)
190 		goto err_exts_init;
191 
192 	if (!handle)
193 		handle = 1;
194 	new->handle = handle;
195 	new->flags = flags;
196 
197 	err = mall_set_parms(net, tp, new, base, tb, tca[TCA_RATE], ovr,
198 			     extack);
199 	if (err)
200 		goto err_set_parms;
201 
202 	if (!tc_skip_hw(new->flags)) {
203 		err = mall_replace_hw_filter(tp, new, (unsigned long)new,
204 					     extack);
205 		if (err)
206 			goto err_replace_hw_filter;
207 	}
208 
209 	if (!tc_in_hw(new->flags))
210 		new->flags |= TCA_CLS_FLAGS_NOT_IN_HW;
211 
212 	*arg = head;
213 	rcu_assign_pointer(tp->root, new);
214 	return 0;
215 
216 err_replace_hw_filter:
217 err_set_parms:
218 	tcf_exts_destroy(&new->exts);
219 err_exts_init:
220 	kfree(new);
221 	return err;
222 }
223 
224 static int mall_delete(struct tcf_proto *tp, void *arg, bool *last,
225 		       struct netlink_ext_ack *extack)
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_reoffload(struct tcf_proto *tp, bool add, tc_setup_cb_t *cb,
243 			  void *cb_priv, struct netlink_ext_ack *extack)
244 {
245 	struct cls_mall_head *head = rtnl_dereference(tp->root);
246 	struct tc_cls_matchall_offload cls_mall = {};
247 	struct tcf_block *block = tp->chain->block;
248 	int err;
249 
250 	if (tc_skip_hw(head->flags))
251 		return 0;
252 
253 	tc_cls_common_offload_init(&cls_mall.common, tp, head->flags, extack);
254 	cls_mall.command = add ?
255 		TC_CLSMATCHALL_REPLACE : TC_CLSMATCHALL_DESTROY;
256 	cls_mall.exts = &head->exts;
257 	cls_mall.cookie = (unsigned long)head;
258 
259 	err = cb(TC_SETUP_CLSMATCHALL, &cls_mall, cb_priv);
260 	if (err) {
261 		if (add && tc_skip_sw(head->flags))
262 			return err;
263 		return 0;
264 	}
265 
266 	tc_cls_offload_cnt_update(block, &head->in_hw_count, &head->flags, add);
267 
268 	return 0;
269 }
270 
271 static int mall_dump(struct net *net, struct tcf_proto *tp, void *fh,
272 		     struct sk_buff *skb, struct tcmsg *t)
273 {
274 	struct cls_mall_head *head = fh;
275 	struct nlattr *nest;
276 
277 	if (!head)
278 		return skb->len;
279 
280 	t->tcm_handle = head->handle;
281 
282 	nest = nla_nest_start(skb, TCA_OPTIONS);
283 	if (!nest)
284 		goto nla_put_failure;
285 
286 	if (head->res.classid &&
287 	    nla_put_u32(skb, TCA_MATCHALL_CLASSID, head->res.classid))
288 		goto nla_put_failure;
289 
290 	if (head->flags && nla_put_u32(skb, TCA_MATCHALL_FLAGS, head->flags))
291 		goto nla_put_failure;
292 
293 	if (tcf_exts_dump(skb, &head->exts))
294 		goto nla_put_failure;
295 
296 	nla_nest_end(skb, nest);
297 
298 	if (tcf_exts_dump_stats(skb, &head->exts) < 0)
299 		goto nla_put_failure;
300 
301 	return skb->len;
302 
303 nla_put_failure:
304 	nla_nest_cancel(skb, nest);
305 	return -1;
306 }
307 
308 static void mall_bind_class(void *fh, u32 classid, unsigned long cl)
309 {
310 	struct cls_mall_head *head = fh;
311 
312 	if (head && head->res.classid == classid)
313 		head->res.class = cl;
314 }
315 
316 static struct tcf_proto_ops cls_mall_ops __read_mostly = {
317 	.kind		= "matchall",
318 	.classify	= mall_classify,
319 	.init		= mall_init,
320 	.destroy	= mall_destroy,
321 	.get		= mall_get,
322 	.change		= mall_change,
323 	.delete		= mall_delete,
324 	.walk		= mall_walk,
325 	.reoffload	= mall_reoffload,
326 	.dump		= mall_dump,
327 	.bind_class	= mall_bind_class,
328 	.owner		= THIS_MODULE,
329 };
330 
331 static int __init cls_mall_init(void)
332 {
333 	return register_tcf_proto_ops(&cls_mall_ops);
334 }
335 
336 static void __exit cls_mall_exit(void)
337 {
338 	unregister_tcf_proto_ops(&cls_mall_ops);
339 }
340 
341 module_init(cls_mall_init);
342 module_exit(cls_mall_exit);
343 
344 MODULE_AUTHOR("Jiri Pirko <jiri@mellanox.com>");
345 MODULE_DESCRIPTION("Match-all classifier");
346 MODULE_LICENSE("GPL v2");
347