xref: /openbmc/linux/net/sched/act_skbedit.c (revision 615c36f5)
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, const 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 	bstats_update(&d->tcf_bstats, skb);
50 
51 	if (d->flags & SKBEDIT_F_PRIORITY)
52 		skb->priority = d->priority;
53 	if (d->flags & SKBEDIT_F_QUEUE_MAPPING &&
54 	    skb->dev->real_num_tx_queues > d->queue_mapping)
55 		skb_set_queue_mapping(skb, d->queue_mapping);
56 	if (d->flags & SKBEDIT_F_MARK)
57 		skb->mark = d->mark;
58 
59 	spin_unlock(&d->tcf_lock);
60 	return d->tcf_action;
61 }
62 
63 static const struct nla_policy skbedit_policy[TCA_SKBEDIT_MAX + 1] = {
64 	[TCA_SKBEDIT_PARMS]		= { .len = sizeof(struct tc_skbedit) },
65 	[TCA_SKBEDIT_PRIORITY]		= { .len = sizeof(u32) },
66 	[TCA_SKBEDIT_QUEUE_MAPPING]	= { .len = sizeof(u16) },
67 	[TCA_SKBEDIT_MARK]		= { .len = sizeof(u32) },
68 };
69 
70 static int tcf_skbedit_init(struct nlattr *nla, struct nlattr *est,
71 			 struct tc_action *a, int ovr, int bind)
72 {
73 	struct nlattr *tb[TCA_SKBEDIT_MAX + 1];
74 	struct tc_skbedit *parm;
75 	struct tcf_skbedit *d;
76 	struct tcf_common *pc;
77 	u32 flags = 0, *priority = NULL, *mark = NULL;
78 	u16 *queue_mapping = NULL;
79 	int ret = 0, err;
80 
81 	if (nla == NULL)
82 		return -EINVAL;
83 
84 	err = nla_parse_nested(tb, TCA_SKBEDIT_MAX, nla, skbedit_policy);
85 	if (err < 0)
86 		return err;
87 
88 	if (tb[TCA_SKBEDIT_PARMS] == NULL)
89 		return -EINVAL;
90 
91 	if (tb[TCA_SKBEDIT_PRIORITY] != NULL) {
92 		flags |= SKBEDIT_F_PRIORITY;
93 		priority = nla_data(tb[TCA_SKBEDIT_PRIORITY]);
94 	}
95 
96 	if (tb[TCA_SKBEDIT_QUEUE_MAPPING] != NULL) {
97 		flags |= SKBEDIT_F_QUEUE_MAPPING;
98 		queue_mapping = nla_data(tb[TCA_SKBEDIT_QUEUE_MAPPING]);
99 	}
100 
101 	if (tb[TCA_SKBEDIT_MARK] != NULL) {
102 		flags |= SKBEDIT_F_MARK;
103 		mark = nla_data(tb[TCA_SKBEDIT_MARK]);
104 	}
105 
106 	if (!flags)
107 		return -EINVAL;
108 
109 	parm = nla_data(tb[TCA_SKBEDIT_PARMS]);
110 
111 	pc = tcf_hash_check(parm->index, a, bind, &skbedit_hash_info);
112 	if (!pc) {
113 		pc = tcf_hash_create(parm->index, est, a, sizeof(*d), bind,
114 				     &skbedit_idx_gen, &skbedit_hash_info);
115 		if (IS_ERR(pc))
116 			return PTR_ERR(pc);
117 
118 		d = to_skbedit(pc);
119 		ret = ACT_P_CREATED;
120 	} else {
121 		d = to_skbedit(pc);
122 		if (!ovr) {
123 			tcf_hash_release(pc, bind, &skbedit_hash_info);
124 			return -EEXIST;
125 		}
126 	}
127 
128 	spin_lock_bh(&d->tcf_lock);
129 
130 	d->flags = flags;
131 	if (flags & SKBEDIT_F_PRIORITY)
132 		d->priority = *priority;
133 	if (flags & SKBEDIT_F_QUEUE_MAPPING)
134 		d->queue_mapping = *queue_mapping;
135 	if (flags & SKBEDIT_F_MARK)
136 		d->mark = *mark;
137 
138 	d->tcf_action = parm->action;
139 
140 	spin_unlock_bh(&d->tcf_lock);
141 
142 	if (ret == ACT_P_CREATED)
143 		tcf_hash_insert(pc, &skbedit_hash_info);
144 	return ret;
145 }
146 
147 static int tcf_skbedit_cleanup(struct tc_action *a, int bind)
148 {
149 	struct tcf_skbedit *d = a->priv;
150 
151 	if (d)
152 		return tcf_hash_release(&d->common, bind, &skbedit_hash_info);
153 	return 0;
154 }
155 
156 static int tcf_skbedit_dump(struct sk_buff *skb, struct tc_action *a,
157 			    int bind, int ref)
158 {
159 	unsigned char *b = skb_tail_pointer(skb);
160 	struct tcf_skbedit *d = a->priv;
161 	struct tc_skbedit opt = {
162 		.index   = d->tcf_index,
163 		.refcnt  = d->tcf_refcnt - ref,
164 		.bindcnt = d->tcf_bindcnt - bind,
165 		.action  = d->tcf_action,
166 	};
167 	struct tcf_t t;
168 
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