xref: /openbmc/linux/net/sched/cls_matchall.c (revision c997aabb)
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 	struct rcu_head	rcu;
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 (tc_skip_sw(head->flags))
33 		return -1;
34 
35 	return tcf_exts_exec(skb, &head->exts, res);
36 }
37 
38 static int mall_init(struct tcf_proto *tp)
39 {
40 	return 0;
41 }
42 
43 static void mall_destroy_rcu(struct rcu_head *rcu)
44 {
45 	struct cls_mall_head *head = container_of(rcu, struct cls_mall_head,
46 						  rcu);
47 
48 	tcf_exts_destroy(&head->exts);
49 	kfree(head);
50 }
51 
52 static int mall_replace_hw_filter(struct tcf_proto *tp,
53 				  struct cls_mall_head *head,
54 				  unsigned long cookie)
55 {
56 	struct net_device *dev = tp->q->dev_queue->dev;
57 	struct tc_to_netdev offload;
58 	struct tc_cls_matchall_offload mall_offload = {0};
59 	int err;
60 
61 	offload.type = TC_SETUP_MATCHALL;
62 	offload.cls_mall = &mall_offload;
63 	offload.cls_mall->command = TC_CLSMATCHALL_REPLACE;
64 	offload.cls_mall->exts = &head->exts;
65 	offload.cls_mall->cookie = cookie;
66 
67 	err = dev->netdev_ops->ndo_setup_tc(dev, tp->q->handle,
68 					    tp->chain->index,
69 					    tp->protocol, &offload);
70 	if (!err)
71 		head->flags |= TCA_CLS_FLAGS_IN_HW;
72 
73 	return err;
74 }
75 
76 static void mall_destroy_hw_filter(struct tcf_proto *tp,
77 				   struct cls_mall_head *head,
78 				   unsigned long cookie)
79 {
80 	struct net_device *dev = tp->q->dev_queue->dev;
81 	struct tc_to_netdev offload;
82 	struct tc_cls_matchall_offload mall_offload = {0};
83 
84 	offload.type = TC_SETUP_MATCHALL;
85 	offload.cls_mall = &mall_offload;
86 	offload.cls_mall->command = TC_CLSMATCHALL_DESTROY;
87 	offload.cls_mall->exts = NULL;
88 	offload.cls_mall->cookie = cookie;
89 
90 	dev->netdev_ops->ndo_setup_tc(dev, tp->q->handle, tp->chain->index,
91 				      tp->protocol, &offload);
92 }
93 
94 static void mall_destroy(struct tcf_proto *tp)
95 {
96 	struct cls_mall_head *head = rtnl_dereference(tp->root);
97 	struct net_device *dev = tp->q->dev_queue->dev;
98 
99 	if (!head)
100 		return;
101 
102 	if (tc_should_offload(dev, tp, head->flags))
103 		mall_destroy_hw_filter(tp, head, (unsigned long) head);
104 
105 	call_rcu(&head->rcu, mall_destroy_rcu);
106 }
107 
108 static unsigned long mall_get(struct tcf_proto *tp, u32 handle)
109 {
110 	return 0UL;
111 }
112 
113 static const struct nla_policy mall_policy[TCA_MATCHALL_MAX + 1] = {
114 	[TCA_MATCHALL_UNSPEC]		= { .type = NLA_UNSPEC },
115 	[TCA_MATCHALL_CLASSID]		= { .type = NLA_U32 },
116 };
117 
118 static int mall_set_parms(struct net *net, struct tcf_proto *tp,
119 			  struct cls_mall_head *head,
120 			  unsigned long base, struct nlattr **tb,
121 			  struct nlattr *est, bool ovr)
122 {
123 	struct tcf_exts e;
124 	int err;
125 
126 	err = tcf_exts_init(&e, TCA_MATCHALL_ACT, 0);
127 	if (err)
128 		return err;
129 	err = tcf_exts_validate(net, tp, tb, est, &e, ovr);
130 	if (err < 0)
131 		goto errout;
132 
133 	if (tb[TCA_MATCHALL_CLASSID]) {
134 		head->res.classid = nla_get_u32(tb[TCA_MATCHALL_CLASSID]);
135 		tcf_bind_filter(tp, &head->res, base);
136 	}
137 
138 	tcf_exts_change(tp, &head->exts, &e);
139 
140 	return 0;
141 errout:
142 	tcf_exts_destroy(&e);
143 	return err;
144 }
145 
146 static int mall_change(struct net *net, struct sk_buff *in_skb,
147 		       struct tcf_proto *tp, unsigned long base,
148 		       u32 handle, struct nlattr **tca,
149 		       unsigned long *arg, bool ovr)
150 {
151 	struct cls_mall_head *head = rtnl_dereference(tp->root);
152 	struct net_device *dev = tp->q->dev_queue->dev;
153 	struct nlattr *tb[TCA_MATCHALL_MAX + 1];
154 	struct cls_mall_head *new;
155 	u32 flags = 0;
156 	int err;
157 
158 	if (!tca[TCA_OPTIONS])
159 		return -EINVAL;
160 
161 	if (head)
162 		return -EEXIST;
163 
164 	err = nla_parse_nested(tb, TCA_MATCHALL_MAX, tca[TCA_OPTIONS],
165 			       mall_policy, NULL);
166 	if (err < 0)
167 		return err;
168 
169 	if (tb[TCA_MATCHALL_FLAGS]) {
170 		flags = nla_get_u32(tb[TCA_MATCHALL_FLAGS]);
171 		if (!tc_flags_valid(flags))
172 			return -EINVAL;
173 	}
174 
175 	new = kzalloc(sizeof(*new), GFP_KERNEL);
176 	if (!new)
177 		return -ENOBUFS;
178 
179 	err = tcf_exts_init(&new->exts, TCA_MATCHALL_ACT, 0);
180 	if (err)
181 		goto err_exts_init;
182 
183 	if (!handle)
184 		handle = 1;
185 	new->handle = handle;
186 	new->flags = flags;
187 
188 	err = mall_set_parms(net, tp, new, base, tb, tca[TCA_RATE], ovr);
189 	if (err)
190 		goto err_set_parms;
191 
192 	if (tc_should_offload(dev, tp, flags)) {
193 		err = mall_replace_hw_filter(tp, new, (unsigned long) new);
194 		if (err) {
195 			if (tc_skip_sw(flags))
196 				goto err_replace_hw_filter;
197 			else
198 				err = 0;
199 		}
200 	}
201 
202 	if (!tc_in_hw(new->flags))
203 		new->flags |= TCA_CLS_FLAGS_NOT_IN_HW;
204 
205 	*arg = (unsigned long) head;
206 	rcu_assign_pointer(tp->root, new);
207 	return 0;
208 
209 err_replace_hw_filter:
210 err_set_parms:
211 	tcf_exts_destroy(&new->exts);
212 err_exts_init:
213 	kfree(new);
214 	return err;
215 }
216 
217 static int mall_delete(struct tcf_proto *tp, unsigned long arg, bool *last)
218 {
219 	return -EOPNOTSUPP;
220 }
221 
222 static void mall_walk(struct tcf_proto *tp, struct tcf_walker *arg)
223 {
224 	struct cls_mall_head *head = rtnl_dereference(tp->root);
225 
226 	if (arg->count < arg->skip)
227 		goto skip;
228 	if (arg->fn(tp, (unsigned long) head, arg) < 0)
229 		arg->stop = 1;
230 skip:
231 	arg->count++;
232 }
233 
234 static int mall_dump(struct net *net, struct tcf_proto *tp, unsigned long fh,
235 		     struct sk_buff *skb, struct tcmsg *t)
236 {
237 	struct cls_mall_head *head = (struct cls_mall_head *) fh;
238 	struct nlattr *nest;
239 
240 	if (!head)
241 		return skb->len;
242 
243 	t->tcm_handle = head->handle;
244 
245 	nest = nla_nest_start(skb, TCA_OPTIONS);
246 	if (!nest)
247 		goto nla_put_failure;
248 
249 	if (head->res.classid &&
250 	    nla_put_u32(skb, TCA_MATCHALL_CLASSID, head->res.classid))
251 		goto nla_put_failure;
252 
253 	if (head->flags && nla_put_u32(skb, TCA_MATCHALL_FLAGS, head->flags))
254 		goto nla_put_failure;
255 
256 	if (tcf_exts_dump(skb, &head->exts))
257 		goto nla_put_failure;
258 
259 	nla_nest_end(skb, nest);
260 
261 	if (tcf_exts_dump_stats(skb, &head->exts) < 0)
262 		goto nla_put_failure;
263 
264 	return skb->len;
265 
266 nla_put_failure:
267 	nla_nest_cancel(skb, nest);
268 	return -1;
269 }
270 
271 static struct tcf_proto_ops cls_mall_ops __read_mostly = {
272 	.kind		= "matchall",
273 	.classify	= mall_classify,
274 	.init		= mall_init,
275 	.destroy	= mall_destroy,
276 	.get		= mall_get,
277 	.change		= mall_change,
278 	.delete		= mall_delete,
279 	.walk		= mall_walk,
280 	.dump		= mall_dump,
281 	.owner		= THIS_MODULE,
282 };
283 
284 static int __init cls_mall_init(void)
285 {
286 	return register_tcf_proto_ops(&cls_mall_ops);
287 }
288 
289 static void __exit cls_mall_exit(void)
290 {
291 	unregister_tcf_proto_ops(&cls_mall_ops);
292 }
293 
294 module_init(cls_mall_init);
295 module_exit(cls_mall_exit);
296 
297 MODULE_AUTHOR("Jiri Pirko <jiri@mellanox.com>");
298 MODULE_DESCRIPTION("Match-all classifier");
299 MODULE_LICENSE("GPL v2");
300