xref: /openbmc/linux/net/sched/cls_matchall.c (revision 3b23dc52)
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_work rwork;
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(struct cls_mall_head *head)
45 {
46 	tcf_exts_destroy(&head->exts);
47 	tcf_exts_put_net(&head->exts);
48 	kfree(head);
49 }
50 
51 static void mall_destroy_work(struct work_struct *work)
52 {
53 	struct cls_mall_head *head = container_of(to_rcu_work(work),
54 						  struct cls_mall_head,
55 						  rwork);
56 	rtnl_lock();
57 	__mall_destroy(head);
58 	rtnl_unlock();
59 }
60 
61 static void mall_destroy_hw_filter(struct tcf_proto *tp,
62 				   struct cls_mall_head *head,
63 				   unsigned long cookie,
64 				   struct netlink_ext_ack *extack)
65 {
66 	struct tc_cls_matchall_offload cls_mall = {};
67 	struct tcf_block *block = tp->chain->block;
68 
69 	tc_cls_common_offload_init(&cls_mall.common, tp, head->flags, extack);
70 	cls_mall.command = TC_CLSMATCHALL_DESTROY;
71 	cls_mall.cookie = cookie;
72 
73 	tc_setup_cb_call(block, NULL, TC_SETUP_CLSMATCHALL, &cls_mall, false);
74 	tcf_block_offload_dec(block, &head->flags);
75 }
76 
77 static int mall_replace_hw_filter(struct tcf_proto *tp,
78 				  struct cls_mall_head *head,
79 				  unsigned long cookie,
80 				  struct netlink_ext_ack *extack)
81 {
82 	struct tc_cls_matchall_offload cls_mall = {};
83 	struct tcf_block *block = tp->chain->block;
84 	bool skip_sw = tc_skip_sw(head->flags);
85 	int err;
86 
87 	tc_cls_common_offload_init(&cls_mall.common, tp, head->flags, extack);
88 	cls_mall.command = TC_CLSMATCHALL_REPLACE;
89 	cls_mall.exts = &head->exts;
90 	cls_mall.cookie = cookie;
91 
92 	err = tc_setup_cb_call(block, NULL, TC_SETUP_CLSMATCHALL,
93 			       &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 		tcf_block_offload_inc(block, &head->flags);
99 	}
100 
101 	if (skip_sw && !(head->flags & TCA_CLS_FLAGS_IN_HW))
102 		return -EINVAL;
103 
104 	return 0;
105 }
106 
107 static void mall_destroy(struct tcf_proto *tp, struct netlink_ext_ack *extack)
108 {
109 	struct cls_mall_head *head = rtnl_dereference(tp->root);
110 
111 	if (!head)
112 		return;
113 
114 	if (!tc_skip_hw(head->flags))
115 		mall_destroy_hw_filter(tp, head, (unsigned long) head, extack);
116 
117 	if (tcf_exts_get_net(&head->exts))
118 		tcf_queue_work(&head->rwork, mall_destroy_work);
119 	else
120 		__mall_destroy(head);
121 }
122 
123 static void *mall_get(struct tcf_proto *tp, u32 handle)
124 {
125 	return NULL;
126 }
127 
128 static const struct nla_policy mall_policy[TCA_MATCHALL_MAX + 1] = {
129 	[TCA_MATCHALL_UNSPEC]		= { .type = NLA_UNSPEC },
130 	[TCA_MATCHALL_CLASSID]		= { .type = NLA_U32 },
131 };
132 
133 static int mall_set_parms(struct net *net, struct tcf_proto *tp,
134 			  struct cls_mall_head *head,
135 			  unsigned long base, struct nlattr **tb,
136 			  struct nlattr *est, bool ovr,
137 			  struct netlink_ext_ack *extack)
138 {
139 	int err;
140 
141 	err = tcf_exts_validate(net, tp, tb, est, &head->exts, ovr, extack);
142 	if (err < 0)
143 		return err;
144 
145 	if (tb[TCA_MATCHALL_CLASSID]) {
146 		head->res.classid = nla_get_u32(tb[TCA_MATCHALL_CLASSID]);
147 		tcf_bind_filter(tp, &head->res, base);
148 	}
149 	return 0;
150 }
151 
152 static int mall_change(struct net *net, struct sk_buff *in_skb,
153 		       struct tcf_proto *tp, unsigned long base,
154 		       u32 handle, struct nlattr **tca,
155 		       void **arg, bool ovr, struct netlink_ext_ack *extack)
156 {
157 	struct cls_mall_head *head = rtnl_dereference(tp->root);
158 	struct nlattr *tb[TCA_MATCHALL_MAX + 1];
159 	struct cls_mall_head *new;
160 	u32 flags = 0;
161 	int err;
162 
163 	if (!tca[TCA_OPTIONS])
164 		return -EINVAL;
165 
166 	if (head)
167 		return -EEXIST;
168 
169 	err = nla_parse_nested(tb, TCA_MATCHALL_MAX, tca[TCA_OPTIONS],
170 			       mall_policy, NULL);
171 	if (err < 0)
172 		return err;
173 
174 	if (tb[TCA_MATCHALL_FLAGS]) {
175 		flags = nla_get_u32(tb[TCA_MATCHALL_FLAGS]);
176 		if (!tc_flags_valid(flags))
177 			return -EINVAL;
178 	}
179 
180 	new = kzalloc(sizeof(*new), GFP_KERNEL);
181 	if (!new)
182 		return -ENOBUFS;
183 
184 	err = tcf_exts_init(&new->exts, TCA_MATCHALL_ACT, 0);
185 	if (err)
186 		goto err_exts_init;
187 
188 	if (!handle)
189 		handle = 1;
190 	new->handle = handle;
191 	new->flags = flags;
192 
193 	err = mall_set_parms(net, tp, new, base, tb, tca[TCA_RATE], ovr,
194 			     extack);
195 	if (err)
196 		goto err_set_parms;
197 
198 	if (!tc_skip_hw(new->flags)) {
199 		err = mall_replace_hw_filter(tp, new, (unsigned long)new,
200 					     extack);
201 		if (err)
202 			goto err_replace_hw_filter;
203 	}
204 
205 	if (!tc_in_hw(new->flags))
206 		new->flags |= TCA_CLS_FLAGS_NOT_IN_HW;
207 
208 	*arg = head;
209 	rcu_assign_pointer(tp->root, new);
210 	return 0;
211 
212 err_replace_hw_filter:
213 err_set_parms:
214 	tcf_exts_destroy(&new->exts);
215 err_exts_init:
216 	kfree(new);
217 	return err;
218 }
219 
220 static int mall_delete(struct tcf_proto *tp, void *arg, bool *last,
221 		       struct netlink_ext_ack *extack)
222 {
223 	return -EOPNOTSUPP;
224 }
225 
226 static void mall_walk(struct tcf_proto *tp, struct tcf_walker *arg)
227 {
228 	struct cls_mall_head *head = rtnl_dereference(tp->root);
229 
230 	if (arg->count < arg->skip)
231 		goto skip;
232 	if (arg->fn(tp, head, arg) < 0)
233 		arg->stop = 1;
234 skip:
235 	arg->count++;
236 }
237 
238 static int mall_dump(struct net *net, struct tcf_proto *tp, void *fh,
239 		     struct sk_buff *skb, struct tcmsg *t)
240 {
241 	struct cls_mall_head *head = fh;
242 	struct nlattr *nest;
243 
244 	if (!head)
245 		return skb->len;
246 
247 	t->tcm_handle = head->handle;
248 
249 	nest = nla_nest_start(skb, TCA_OPTIONS);
250 	if (!nest)
251 		goto nla_put_failure;
252 
253 	if (head->res.classid &&
254 	    nla_put_u32(skb, TCA_MATCHALL_CLASSID, head->res.classid))
255 		goto nla_put_failure;
256 
257 	if (head->flags && nla_put_u32(skb, TCA_MATCHALL_FLAGS, head->flags))
258 		goto nla_put_failure;
259 
260 	if (tcf_exts_dump(skb, &head->exts))
261 		goto nla_put_failure;
262 
263 	nla_nest_end(skb, nest);
264 
265 	if (tcf_exts_dump_stats(skb, &head->exts) < 0)
266 		goto nla_put_failure;
267 
268 	return skb->len;
269 
270 nla_put_failure:
271 	nla_nest_cancel(skb, nest);
272 	return -1;
273 }
274 
275 static void mall_bind_class(void *fh, u32 classid, unsigned long cl)
276 {
277 	struct cls_mall_head *head = fh;
278 
279 	if (head && head->res.classid == classid)
280 		head->res.class = cl;
281 }
282 
283 static struct tcf_proto_ops cls_mall_ops __read_mostly = {
284 	.kind		= "matchall",
285 	.classify	= mall_classify,
286 	.init		= mall_init,
287 	.destroy	= mall_destroy,
288 	.get		= mall_get,
289 	.change		= mall_change,
290 	.delete		= mall_delete,
291 	.walk		= mall_walk,
292 	.dump		= mall_dump,
293 	.bind_class	= mall_bind_class,
294 	.owner		= THIS_MODULE,
295 };
296 
297 static int __init cls_mall_init(void)
298 {
299 	return register_tcf_proto_ops(&cls_mall_ops);
300 }
301 
302 static void __exit cls_mall_exit(void)
303 {
304 	unregister_tcf_proto_ops(&cls_mall_ops);
305 }
306 
307 module_init(cls_mall_init);
308 module_exit(cls_mall_exit);
309 
310 MODULE_AUTHOR("Jiri Pirko <jiri@mellanox.com>");
311 MODULE_DESCRIPTION("Match-all classifier");
312 MODULE_LICENSE("GPL v2");
313