xref: /openbmc/linux/net/sched/cls_matchall.c (revision 5b4cb650)
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, 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, TC_SETUP_CLSMATCHALL, &cls_mall, skip_sw);
94 	if (err < 0) {
95 		mall_destroy_hw_filter(tp, head, cookie, NULL);
96 		return err;
97 	} else if (err > 0) {
98 		head->in_hw_count = err;
99 		tcf_block_offload_inc(block, &head->flags);
100 	}
101 
102 	if (skip_sw && !(head->flags & TCA_CLS_FLAGS_IN_HW))
103 		return -EINVAL;
104 
105 	return 0;
106 }
107 
108 static void mall_destroy(struct tcf_proto *tp, struct netlink_ext_ack *extack)
109 {
110 	struct cls_mall_head *head = rtnl_dereference(tp->root);
111 
112 	if (!head)
113 		return;
114 
115 	tcf_unbind_filter(tp, &head->res);
116 
117 	if (!tc_skip_hw(head->flags))
118 		mall_destroy_hw_filter(tp, head, (unsigned long) head, extack);
119 
120 	if (tcf_exts_get_net(&head->exts))
121 		tcf_queue_work(&head->rwork, mall_destroy_work);
122 	else
123 		__mall_destroy(head);
124 }
125 
126 static void *mall_get(struct tcf_proto *tp, u32 handle)
127 {
128 	return NULL;
129 }
130 
131 static const struct nla_policy mall_policy[TCA_MATCHALL_MAX + 1] = {
132 	[TCA_MATCHALL_UNSPEC]		= { .type = NLA_UNSPEC },
133 	[TCA_MATCHALL_CLASSID]		= { .type = NLA_U32 },
134 };
135 
136 static int mall_set_parms(struct net *net, struct tcf_proto *tp,
137 			  struct cls_mall_head *head,
138 			  unsigned long base, struct nlattr **tb,
139 			  struct nlattr *est, bool ovr,
140 			  struct netlink_ext_ack *extack)
141 {
142 	int err;
143 
144 	err = tcf_exts_validate(net, tp, tb, est, &head->exts, ovr, extack);
145 	if (err < 0)
146 		return err;
147 
148 	if (tb[TCA_MATCHALL_CLASSID]) {
149 		head->res.classid = nla_get_u32(tb[TCA_MATCHALL_CLASSID]);
150 		tcf_bind_filter(tp, &head->res, base);
151 	}
152 	return 0;
153 }
154 
155 static int mall_change(struct net *net, struct sk_buff *in_skb,
156 		       struct tcf_proto *tp, unsigned long base,
157 		       u32 handle, struct nlattr **tca,
158 		       void **arg, bool ovr, struct netlink_ext_ack *extack)
159 {
160 	struct cls_mall_head *head = rtnl_dereference(tp->root);
161 	struct nlattr *tb[TCA_MATCHALL_MAX + 1];
162 	struct cls_mall_head *new;
163 	u32 flags = 0;
164 	int err;
165 
166 	if (!tca[TCA_OPTIONS])
167 		return -EINVAL;
168 
169 	if (head)
170 		return -EEXIST;
171 
172 	err = nla_parse_nested(tb, TCA_MATCHALL_MAX, tca[TCA_OPTIONS],
173 			       mall_policy, NULL);
174 	if (err < 0)
175 		return err;
176 
177 	if (tb[TCA_MATCHALL_FLAGS]) {
178 		flags = nla_get_u32(tb[TCA_MATCHALL_FLAGS]);
179 		if (!tc_flags_valid(flags))
180 			return -EINVAL;
181 	}
182 
183 	new = kzalloc(sizeof(*new), GFP_KERNEL);
184 	if (!new)
185 		return -ENOBUFS;
186 
187 	err = tcf_exts_init(&new->exts, TCA_MATCHALL_ACT, 0);
188 	if (err)
189 		goto err_exts_init;
190 
191 	if (!handle)
192 		handle = 1;
193 	new->handle = handle;
194 	new->flags = flags;
195 
196 	err = mall_set_parms(net, tp, new, base, tb, tca[TCA_RATE], ovr,
197 			     extack);
198 	if (err)
199 		goto err_set_parms;
200 
201 	if (!tc_skip_hw(new->flags)) {
202 		err = mall_replace_hw_filter(tp, new, (unsigned long)new,
203 					     extack);
204 		if (err)
205 			goto err_replace_hw_filter;
206 	}
207 
208 	if (!tc_in_hw(new->flags))
209 		new->flags |= TCA_CLS_FLAGS_NOT_IN_HW;
210 
211 	*arg = head;
212 	rcu_assign_pointer(tp->root, new);
213 	return 0;
214 
215 err_replace_hw_filter:
216 err_set_parms:
217 	tcf_exts_destroy(&new->exts);
218 err_exts_init:
219 	kfree(new);
220 	return err;
221 }
222 
223 static int mall_delete(struct tcf_proto *tp, void *arg, bool *last,
224 		       struct netlink_ext_ack *extack)
225 {
226 	return -EOPNOTSUPP;
227 }
228 
229 static void mall_walk(struct tcf_proto *tp, struct tcf_walker *arg)
230 {
231 	struct cls_mall_head *head = rtnl_dereference(tp->root);
232 
233 	if (arg->count < arg->skip)
234 		goto skip;
235 	if (arg->fn(tp, head, arg) < 0)
236 		arg->stop = 1;
237 skip:
238 	arg->count++;
239 }
240 
241 static int mall_reoffload(struct tcf_proto *tp, bool add, tc_setup_cb_t *cb,
242 			  void *cb_priv, struct netlink_ext_ack *extack)
243 {
244 	struct cls_mall_head *head = rtnl_dereference(tp->root);
245 	struct tc_cls_matchall_offload cls_mall = {};
246 	struct tcf_block *block = tp->chain->block;
247 	int err;
248 
249 	if (tc_skip_hw(head->flags))
250 		return 0;
251 
252 	tc_cls_common_offload_init(&cls_mall.common, tp, head->flags, extack);
253 	cls_mall.command = add ?
254 		TC_CLSMATCHALL_REPLACE : TC_CLSMATCHALL_DESTROY;
255 	cls_mall.exts = &head->exts;
256 	cls_mall.cookie = (unsigned long)head;
257 
258 	err = cb(TC_SETUP_CLSMATCHALL, &cls_mall, cb_priv);
259 	if (err) {
260 		if (add && tc_skip_sw(head->flags))
261 			return err;
262 		return 0;
263 	}
264 
265 	tc_cls_offload_cnt_update(block, &head->in_hw_count, &head->flags, add);
266 
267 	return 0;
268 }
269 
270 static int mall_dump(struct net *net, struct tcf_proto *tp, void *fh,
271 		     struct sk_buff *skb, struct tcmsg *t)
272 {
273 	struct cls_mall_head *head = fh;
274 	struct nlattr *nest;
275 
276 	if (!head)
277 		return skb->len;
278 
279 	t->tcm_handle = head->handle;
280 
281 	nest = nla_nest_start(skb, TCA_OPTIONS);
282 	if (!nest)
283 		goto nla_put_failure;
284 
285 	if (head->res.classid &&
286 	    nla_put_u32(skb, TCA_MATCHALL_CLASSID, head->res.classid))
287 		goto nla_put_failure;
288 
289 	if (head->flags && nla_put_u32(skb, TCA_MATCHALL_FLAGS, head->flags))
290 		goto nla_put_failure;
291 
292 	if (tcf_exts_dump(skb, &head->exts))
293 		goto nla_put_failure;
294 
295 	nla_nest_end(skb, nest);
296 
297 	if (tcf_exts_dump_stats(skb, &head->exts) < 0)
298 		goto nla_put_failure;
299 
300 	return skb->len;
301 
302 nla_put_failure:
303 	nla_nest_cancel(skb, nest);
304 	return -1;
305 }
306 
307 static void mall_bind_class(void *fh, u32 classid, unsigned long cl)
308 {
309 	struct cls_mall_head *head = fh;
310 
311 	if (head && head->res.classid == classid)
312 		head->res.class = cl;
313 }
314 
315 static struct tcf_proto_ops cls_mall_ops __read_mostly = {
316 	.kind		= "matchall",
317 	.classify	= mall_classify,
318 	.init		= mall_init,
319 	.destroy	= mall_destroy,
320 	.get		= mall_get,
321 	.change		= mall_change,
322 	.delete		= mall_delete,
323 	.walk		= mall_walk,
324 	.reoffload	= mall_reoffload,
325 	.dump		= mall_dump,
326 	.bind_class	= mall_bind_class,
327 	.owner		= THIS_MODULE,
328 };
329 
330 static int __init cls_mall_init(void)
331 {
332 	return register_tcf_proto_ops(&cls_mall_ops);
333 }
334 
335 static void __exit cls_mall_exit(void)
336 {
337 	unregister_tcf_proto_ops(&cls_mall_ops);
338 }
339 
340 module_init(cls_mall_init);
341 module_exit(cls_mall_exit);
342 
343 MODULE_AUTHOR("Jiri Pirko <jiri@mellanox.com>");
344 MODULE_DESCRIPTION("Match-all classifier");
345 MODULE_LICENSE("GPL v2");
346