xref: /openbmc/linux/net/sched/cls_matchall.c (revision 41e4b7dc)
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 	*res = head->res;
36 	return tcf_exts_exec(skb, &head->exts, res);
37 }
38 
39 static int mall_init(struct tcf_proto *tp)
40 {
41 	return 0;
42 }
43 
44 static void mall_destroy_rcu(struct rcu_head *rcu)
45 {
46 	struct cls_mall_head *head = container_of(rcu, struct cls_mall_head,
47 						  rcu);
48 
49 	tcf_exts_destroy(&head->exts);
50 	kfree(head);
51 }
52 
53 static int mall_replace_hw_filter(struct tcf_proto *tp,
54 				  struct cls_mall_head *head,
55 				  unsigned long cookie)
56 {
57 	struct net_device *dev = tp->q->dev_queue->dev;
58 	struct tc_cls_matchall_offload cls_mall = {};
59 	int err;
60 
61 	tc_cls_common_offload_init(&cls_mall.common, tp);
62 	cls_mall.command = TC_CLSMATCHALL_REPLACE;
63 	cls_mall.exts = &head->exts;
64 	cls_mall.cookie = cookie;
65 
66 	err = dev->netdev_ops->ndo_setup_tc(dev, TC_SETUP_CLSMATCHALL,
67 					    &cls_mall);
68 	if (!err)
69 		head->flags |= TCA_CLS_FLAGS_IN_HW;
70 
71 	return err;
72 }
73 
74 static void mall_destroy_hw_filter(struct tcf_proto *tp,
75 				   struct cls_mall_head *head,
76 				   unsigned long cookie)
77 {
78 	struct net_device *dev = tp->q->dev_queue->dev;
79 	struct tc_cls_matchall_offload cls_mall = {};
80 
81 	tc_cls_common_offload_init(&cls_mall.common, tp);
82 	cls_mall.command = TC_CLSMATCHALL_DESTROY;
83 	cls_mall.cookie = cookie;
84 
85 	dev->netdev_ops->ndo_setup_tc(dev, TC_SETUP_CLSMATCHALL, &cls_mall);
86 }
87 
88 static void mall_destroy(struct tcf_proto *tp)
89 {
90 	struct cls_mall_head *head = rtnl_dereference(tp->root);
91 	struct net_device *dev = tp->q->dev_queue->dev;
92 
93 	if (!head)
94 		return;
95 
96 	if (tc_should_offload(dev, head->flags))
97 		mall_destroy_hw_filter(tp, head, (unsigned long) head);
98 
99 	call_rcu(&head->rcu, mall_destroy_rcu);
100 }
101 
102 static void *mall_get(struct tcf_proto *tp, u32 handle)
103 {
104 	return NULL;
105 }
106 
107 static const struct nla_policy mall_policy[TCA_MATCHALL_MAX + 1] = {
108 	[TCA_MATCHALL_UNSPEC]		= { .type = NLA_UNSPEC },
109 	[TCA_MATCHALL_CLASSID]		= { .type = NLA_U32 },
110 };
111 
112 static int mall_set_parms(struct net *net, struct tcf_proto *tp,
113 			  struct cls_mall_head *head,
114 			  unsigned long base, struct nlattr **tb,
115 			  struct nlattr *est, bool ovr)
116 {
117 	int err;
118 
119 	err = tcf_exts_validate(net, tp, tb, est, &head->exts, ovr);
120 	if (err < 0)
121 		return err;
122 
123 	if (tb[TCA_MATCHALL_CLASSID]) {
124 		head->res.classid = nla_get_u32(tb[TCA_MATCHALL_CLASSID]);
125 		tcf_bind_filter(tp, &head->res, base);
126 	}
127 	return 0;
128 }
129 
130 static int mall_change(struct net *net, struct sk_buff *in_skb,
131 		       struct tcf_proto *tp, unsigned long base,
132 		       u32 handle, struct nlattr **tca,
133 		       void **arg, bool ovr)
134 {
135 	struct cls_mall_head *head = rtnl_dereference(tp->root);
136 	struct net_device *dev = tp->q->dev_queue->dev;
137 	struct nlattr *tb[TCA_MATCHALL_MAX + 1];
138 	struct cls_mall_head *new;
139 	u32 flags = 0;
140 	int err;
141 
142 	if (!tca[TCA_OPTIONS])
143 		return -EINVAL;
144 
145 	if (head)
146 		return -EEXIST;
147 
148 	err = nla_parse_nested(tb, TCA_MATCHALL_MAX, tca[TCA_OPTIONS],
149 			       mall_policy, NULL);
150 	if (err < 0)
151 		return err;
152 
153 	if (tb[TCA_MATCHALL_FLAGS]) {
154 		flags = nla_get_u32(tb[TCA_MATCHALL_FLAGS]);
155 		if (!tc_flags_valid(flags))
156 			return -EINVAL;
157 	}
158 
159 	new = kzalloc(sizeof(*new), GFP_KERNEL);
160 	if (!new)
161 		return -ENOBUFS;
162 
163 	err = tcf_exts_init(&new->exts, TCA_MATCHALL_ACT, 0);
164 	if (err)
165 		goto err_exts_init;
166 
167 	if (!handle)
168 		handle = 1;
169 	new->handle = handle;
170 	new->flags = flags;
171 
172 	err = mall_set_parms(net, tp, new, base, tb, tca[TCA_RATE], ovr);
173 	if (err)
174 		goto err_set_parms;
175 
176 	if (tc_should_offload(dev, flags)) {
177 		err = mall_replace_hw_filter(tp, new, (unsigned long) new);
178 		if (err) {
179 			if (tc_skip_sw(flags))
180 				goto err_replace_hw_filter;
181 			else
182 				err = 0;
183 		}
184 	}
185 
186 	if (!tc_in_hw(new->flags))
187 		new->flags |= TCA_CLS_FLAGS_NOT_IN_HW;
188 
189 	*arg = head;
190 	rcu_assign_pointer(tp->root, new);
191 	return 0;
192 
193 err_replace_hw_filter:
194 err_set_parms:
195 	tcf_exts_destroy(&new->exts);
196 err_exts_init:
197 	kfree(new);
198 	return err;
199 }
200 
201 static int mall_delete(struct tcf_proto *tp, void *arg, bool *last)
202 {
203 	return -EOPNOTSUPP;
204 }
205 
206 static void mall_walk(struct tcf_proto *tp, struct tcf_walker *arg)
207 {
208 	struct cls_mall_head *head = rtnl_dereference(tp->root);
209 
210 	if (arg->count < arg->skip)
211 		goto skip;
212 	if (arg->fn(tp, head, arg) < 0)
213 		arg->stop = 1;
214 skip:
215 	arg->count++;
216 }
217 
218 static int mall_dump(struct net *net, struct tcf_proto *tp, void *fh,
219 		     struct sk_buff *skb, struct tcmsg *t)
220 {
221 	struct cls_mall_head *head = fh;
222 	struct nlattr *nest;
223 
224 	if (!head)
225 		return skb->len;
226 
227 	t->tcm_handle = head->handle;
228 
229 	nest = nla_nest_start(skb, TCA_OPTIONS);
230 	if (!nest)
231 		goto nla_put_failure;
232 
233 	if (head->res.classid &&
234 	    nla_put_u32(skb, TCA_MATCHALL_CLASSID, head->res.classid))
235 		goto nla_put_failure;
236 
237 	if (head->flags && nla_put_u32(skb, TCA_MATCHALL_FLAGS, head->flags))
238 		goto nla_put_failure;
239 
240 	if (tcf_exts_dump(skb, &head->exts))
241 		goto nla_put_failure;
242 
243 	nla_nest_end(skb, nest);
244 
245 	if (tcf_exts_dump_stats(skb, &head->exts) < 0)
246 		goto nla_put_failure;
247 
248 	return skb->len;
249 
250 nla_put_failure:
251 	nla_nest_cancel(skb, nest);
252 	return -1;
253 }
254 
255 static void mall_bind_class(void *fh, u32 classid, unsigned long cl)
256 {
257 	struct cls_mall_head *head = fh;
258 
259 	if (head && head->res.classid == classid)
260 		head->res.class = cl;
261 }
262 
263 static struct tcf_proto_ops cls_mall_ops __read_mostly = {
264 	.kind		= "matchall",
265 	.classify	= mall_classify,
266 	.init		= mall_init,
267 	.destroy	= mall_destroy,
268 	.get		= mall_get,
269 	.change		= mall_change,
270 	.delete		= mall_delete,
271 	.walk		= mall_walk,
272 	.dump		= mall_dump,
273 	.bind_class	= mall_bind_class,
274 	.owner		= THIS_MODULE,
275 };
276 
277 static int __init cls_mall_init(void)
278 {
279 	return register_tcf_proto_ops(&cls_mall_ops);
280 }
281 
282 static void __exit cls_mall_exit(void)
283 {
284 	unregister_tcf_proto_ops(&cls_mall_ops);
285 }
286 
287 module_init(cls_mall_init);
288 module_exit(cls_mall_exit);
289 
290 MODULE_AUTHOR("Jiri Pirko <jiri@mellanox.com>");
291 MODULE_DESCRIPTION("Match-all classifier");
292 MODULE_LICENSE("GPL v2");
293