xref: /openbmc/linux/net/sched/act_skbedit.c (revision b6dcefde)
1 /*
2  * Copyright (c) 2008, Intel Corporation.
3  *
4  * This program is free software; you can redistribute it and/or modify it
5  * under the terms and conditions of the GNU General Public License,
6  * version 2, as published by the Free Software Foundation.
7  *
8  * This program is distributed in the hope it will be useful, but WITHOUT
9  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
10  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
11  * more details.
12  *
13  * You should have received a copy of the GNU General Public License along with
14  * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
15  * Place - Suite 330, Boston, MA 02111-1307 USA.
16  *
17  * Author: Alexander Duyck <alexander.h.duyck@intel.com>
18  */
19 
20 #include <linux/module.h>
21 #include <linux/init.h>
22 #include <linux/kernel.h>
23 #include <linux/skbuff.h>
24 #include <linux/rtnetlink.h>
25 #include <net/netlink.h>
26 #include <net/pkt_sched.h>
27 
28 #include <linux/tc_act/tc_skbedit.h>
29 #include <net/tc_act/tc_skbedit.h>
30 
31 #define SKBEDIT_TAB_MASK     15
32 static struct tcf_common *tcf_skbedit_ht[SKBEDIT_TAB_MASK + 1];
33 static u32 skbedit_idx_gen;
34 static DEFINE_RWLOCK(skbedit_lock);
35 
36 static struct tcf_hashinfo skbedit_hash_info = {
37 	.htab	=	tcf_skbedit_ht,
38 	.hmask	=	SKBEDIT_TAB_MASK,
39 	.lock	=	&skbedit_lock,
40 };
41 
42 static int tcf_skbedit(struct sk_buff *skb, struct tc_action *a,
43 		       struct tcf_result *res)
44 {
45 	struct tcf_skbedit *d = a->priv;
46 
47 	spin_lock(&d->tcf_lock);
48 	d->tcf_tm.lastuse = jiffies;
49 	d->tcf_bstats.bytes += qdisc_pkt_len(skb);
50 	d->tcf_bstats.packets++;
51 
52 	if (d->flags & SKBEDIT_F_PRIORITY)
53 		skb->priority = d->priority;
54 	if (d->flags & SKBEDIT_F_QUEUE_MAPPING &&
55 	    skb->dev->real_num_tx_queues > d->queue_mapping)
56 		skb_set_queue_mapping(skb, d->queue_mapping);
57 	if (d->flags & SKBEDIT_F_MARK)
58 		skb->mark = d->mark;
59 
60 	spin_unlock(&d->tcf_lock);
61 	return d->tcf_action;
62 }
63 
64 static const struct nla_policy skbedit_policy[TCA_SKBEDIT_MAX + 1] = {
65 	[TCA_SKBEDIT_PARMS]		= { .len = sizeof(struct tc_skbedit) },
66 	[TCA_SKBEDIT_PRIORITY]		= { .len = sizeof(u32) },
67 	[TCA_SKBEDIT_QUEUE_MAPPING]	= { .len = sizeof(u16) },
68 	[TCA_SKBEDIT_MARK]		= { .len = sizeof(u32) },
69 };
70 
71 static int tcf_skbedit_init(struct nlattr *nla, struct nlattr *est,
72 			 struct tc_action *a, int ovr, int bind)
73 {
74 	struct nlattr *tb[TCA_SKBEDIT_MAX + 1];
75 	struct tc_skbedit *parm;
76 	struct tcf_skbedit *d;
77 	struct tcf_common *pc;
78 	u32 flags = 0, *priority = NULL, *mark = NULL;
79 	u16 *queue_mapping = NULL;
80 	int ret = 0, err;
81 
82 	if (nla == NULL)
83 		return -EINVAL;
84 
85 	err = nla_parse_nested(tb, TCA_SKBEDIT_MAX, nla, skbedit_policy);
86 	if (err < 0)
87 		return err;
88 
89 	if (tb[TCA_SKBEDIT_PARMS] == NULL)
90 		return -EINVAL;
91 
92 	if (tb[TCA_SKBEDIT_PRIORITY] != NULL) {
93 		flags |= SKBEDIT_F_PRIORITY;
94 		priority = nla_data(tb[TCA_SKBEDIT_PRIORITY]);
95 	}
96 
97 	if (tb[TCA_SKBEDIT_QUEUE_MAPPING] != NULL) {
98 		flags |= SKBEDIT_F_QUEUE_MAPPING;
99 		queue_mapping = nla_data(tb[TCA_SKBEDIT_QUEUE_MAPPING]);
100 	}
101 
102 	if (tb[TCA_SKBEDIT_MARK] != NULL) {
103 		flags |= SKBEDIT_F_MARK;
104 		mark = nla_data(tb[TCA_SKBEDIT_MARK]);
105 	}
106 
107 	if (!flags)
108 		return -EINVAL;
109 
110 	parm = nla_data(tb[TCA_SKBEDIT_PARMS]);
111 
112 	pc = tcf_hash_check(parm->index, a, bind, &skbedit_hash_info);
113 	if (!pc) {
114 		pc = tcf_hash_create(parm->index, est, a, sizeof(*d), bind,
115 				     &skbedit_idx_gen, &skbedit_hash_info);
116 		if (IS_ERR(pc))
117 		    return PTR_ERR(pc);
118 
119 		d = to_skbedit(pc);
120 		ret = ACT_P_CREATED;
121 	} else {
122 		d = to_skbedit(pc);
123 		if (!ovr) {
124 			tcf_hash_release(pc, bind, &skbedit_hash_info);
125 			return -EEXIST;
126 		}
127 	}
128 
129 	spin_lock_bh(&d->tcf_lock);
130 
131 	d->flags = flags;
132 	if (flags & SKBEDIT_F_PRIORITY)
133 		d->priority = *priority;
134 	if (flags & SKBEDIT_F_QUEUE_MAPPING)
135 		d->queue_mapping = *queue_mapping;
136 	if (flags & SKBEDIT_F_MARK)
137 		d->mark = *mark;
138 
139 	d->tcf_action = parm->action;
140 
141 	spin_unlock_bh(&d->tcf_lock);
142 
143 	if (ret == ACT_P_CREATED)
144 		tcf_hash_insert(pc, &skbedit_hash_info);
145 	return ret;
146 }
147 
148 static inline int tcf_skbedit_cleanup(struct tc_action *a, int bind)
149 {
150 	struct tcf_skbedit *d = a->priv;
151 
152 	if (d)
153 		return tcf_hash_release(&d->common, bind, &skbedit_hash_info);
154 	return 0;
155 }
156 
157 static inline int tcf_skbedit_dump(struct sk_buff *skb, struct tc_action *a,
158 				int bind, int ref)
159 {
160 	unsigned char *b = skb_tail_pointer(skb);
161 	struct tcf_skbedit *d = a->priv;
162 	struct tc_skbedit opt;
163 	struct tcf_t t;
164 
165 	opt.index = d->tcf_index;
166 	opt.refcnt = d->tcf_refcnt - ref;
167 	opt.bindcnt = d->tcf_bindcnt - bind;
168 	opt.action = d->tcf_action;
169 	NLA_PUT(skb, TCA_SKBEDIT_PARMS, sizeof(opt), &opt);
170 	if (d->flags & SKBEDIT_F_PRIORITY)
171 		NLA_PUT(skb, TCA_SKBEDIT_PRIORITY, sizeof(d->priority),
172 			&d->priority);
173 	if (d->flags & SKBEDIT_F_QUEUE_MAPPING)
174 		NLA_PUT(skb, TCA_SKBEDIT_QUEUE_MAPPING,
175 			sizeof(d->queue_mapping), &d->queue_mapping);
176 	if (d->flags & SKBEDIT_F_MARK)
177 		NLA_PUT(skb, TCA_SKBEDIT_MARK, sizeof(d->mark),
178 			&d->mark);
179 	t.install = jiffies_to_clock_t(jiffies - d->tcf_tm.install);
180 	t.lastuse = jiffies_to_clock_t(jiffies - d->tcf_tm.lastuse);
181 	t.expires = jiffies_to_clock_t(d->tcf_tm.expires);
182 	NLA_PUT(skb, TCA_SKBEDIT_TM, sizeof(t), &t);
183 	return skb->len;
184 
185 nla_put_failure:
186 	nlmsg_trim(skb, b);
187 	return -1;
188 }
189 
190 static struct tc_action_ops act_skbedit_ops = {
191 	.kind		=	"skbedit",
192 	.hinfo		=	&skbedit_hash_info,
193 	.type		=	TCA_ACT_SKBEDIT,
194 	.capab		=	TCA_CAP_NONE,
195 	.owner		=	THIS_MODULE,
196 	.act		=	tcf_skbedit,
197 	.dump		=	tcf_skbedit_dump,
198 	.cleanup	=	tcf_skbedit_cleanup,
199 	.init		=	tcf_skbedit_init,
200 	.walk		=	tcf_generic_walker,
201 };
202 
203 MODULE_AUTHOR("Alexander Duyck, <alexander.h.duyck@intel.com>");
204 MODULE_DESCRIPTION("SKB Editing");
205 MODULE_LICENSE("GPL");
206 
207 static int __init skbedit_init_module(void)
208 {
209 	return tcf_register_action(&act_skbedit_ops);
210 }
211 
212 static void __exit skbedit_cleanup_module(void)
213 {
214 	tcf_unregister_action(&act_skbedit_ops);
215 }
216 
217 module_init(skbedit_init_module);
218 module_exit(skbedit_cleanup_module);
219