xref: /openbmc/linux/net/sched/act_skbedit.c (revision b627b4ed)
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 
58 	spin_unlock(&d->tcf_lock);
59 	return d->tcf_action;
60 }
61 
62 static const struct nla_policy skbedit_policy[TCA_SKBEDIT_MAX + 1] = {
63 	[TCA_SKBEDIT_PARMS]		= { .len = sizeof(struct tc_skbedit) },
64 	[TCA_SKBEDIT_PRIORITY]		= { .len = sizeof(u32) },
65 	[TCA_SKBEDIT_QUEUE_MAPPING]	= { .len = sizeof(u16) },
66 };
67 
68 static int tcf_skbedit_init(struct nlattr *nla, struct nlattr *est,
69 			 struct tc_action *a, int ovr, int bind)
70 {
71 	struct nlattr *tb[TCA_SKBEDIT_MAX + 1];
72 	struct tc_skbedit *parm;
73 	struct tcf_skbedit *d;
74 	struct tcf_common *pc;
75 	u32 flags = 0, *priority = NULL;
76 	u16 *queue_mapping = NULL;
77 	int ret = 0, err;
78 
79 	if (nla == NULL)
80 		return -EINVAL;
81 
82 	err = nla_parse_nested(tb, TCA_SKBEDIT_MAX, nla, skbedit_policy);
83 	if (err < 0)
84 		return err;
85 
86 	if (tb[TCA_SKBEDIT_PARMS] == NULL)
87 		return -EINVAL;
88 
89 	if (tb[TCA_SKBEDIT_PRIORITY] != NULL) {
90 		flags |= SKBEDIT_F_PRIORITY;
91 		priority = nla_data(tb[TCA_SKBEDIT_PRIORITY]);
92 	}
93 
94 	if (tb[TCA_SKBEDIT_QUEUE_MAPPING] != NULL) {
95 		flags |= SKBEDIT_F_QUEUE_MAPPING;
96 		queue_mapping = nla_data(tb[TCA_SKBEDIT_QUEUE_MAPPING]);
97 	}
98 	if (!flags)
99 		return -EINVAL;
100 
101 	parm = nla_data(tb[TCA_SKBEDIT_PARMS]);
102 
103 	pc = tcf_hash_check(parm->index, a, bind, &skbedit_hash_info);
104 	if (!pc) {
105 		pc = tcf_hash_create(parm->index, est, a, sizeof(*d), bind,
106 				     &skbedit_idx_gen, &skbedit_hash_info);
107 		if (IS_ERR(pc))
108 		    return PTR_ERR(pc);
109 
110 		d = to_skbedit(pc);
111 		ret = ACT_P_CREATED;
112 	} else {
113 		d = to_skbedit(pc);
114 		if (!ovr) {
115 			tcf_hash_release(pc, bind, &skbedit_hash_info);
116 			return -EEXIST;
117 		}
118 	}
119 
120 	spin_lock_bh(&d->tcf_lock);
121 
122 	d->flags = flags;
123 	if (flags & SKBEDIT_F_PRIORITY)
124 		d->priority = *priority;
125 	if (flags & SKBEDIT_F_QUEUE_MAPPING)
126 		d->queue_mapping = *queue_mapping;
127 	d->tcf_action = parm->action;
128 
129 	spin_unlock_bh(&d->tcf_lock);
130 
131 	if (ret == ACT_P_CREATED)
132 		tcf_hash_insert(pc, &skbedit_hash_info);
133 	return ret;
134 }
135 
136 static inline int tcf_skbedit_cleanup(struct tc_action *a, int bind)
137 {
138 	struct tcf_skbedit *d = a->priv;
139 
140 	if (d)
141 		return tcf_hash_release(&d->common, bind, &skbedit_hash_info);
142 	return 0;
143 }
144 
145 static inline int tcf_skbedit_dump(struct sk_buff *skb, struct tc_action *a,
146 				int bind, int ref)
147 {
148 	unsigned char *b = skb_tail_pointer(skb);
149 	struct tcf_skbedit *d = a->priv;
150 	struct tc_skbedit opt;
151 	struct tcf_t t;
152 
153 	opt.index = d->tcf_index;
154 	opt.refcnt = d->tcf_refcnt - ref;
155 	opt.bindcnt = d->tcf_bindcnt - bind;
156 	opt.action = d->tcf_action;
157 	NLA_PUT(skb, TCA_SKBEDIT_PARMS, sizeof(opt), &opt);
158 	if (d->flags & SKBEDIT_F_PRIORITY)
159 		NLA_PUT(skb, TCA_SKBEDIT_PRIORITY, sizeof(d->priority),
160 			&d->priority);
161 	if (d->flags & SKBEDIT_F_QUEUE_MAPPING)
162 		NLA_PUT(skb, TCA_SKBEDIT_QUEUE_MAPPING,
163 			sizeof(d->queue_mapping), &d->queue_mapping);
164 	t.install = jiffies_to_clock_t(jiffies - d->tcf_tm.install);
165 	t.lastuse = jiffies_to_clock_t(jiffies - d->tcf_tm.lastuse);
166 	t.expires = jiffies_to_clock_t(d->tcf_tm.expires);
167 	NLA_PUT(skb, TCA_SKBEDIT_TM, sizeof(t), &t);
168 	return skb->len;
169 
170 nla_put_failure:
171 	nlmsg_trim(skb, b);
172 	return -1;
173 }
174 
175 static struct tc_action_ops act_skbedit_ops = {
176 	.kind		=	"skbedit",
177 	.hinfo		=	&skbedit_hash_info,
178 	.type		=	TCA_ACT_SKBEDIT,
179 	.capab		=	TCA_CAP_NONE,
180 	.owner		=	THIS_MODULE,
181 	.act		=	tcf_skbedit,
182 	.dump		=	tcf_skbedit_dump,
183 	.cleanup	=	tcf_skbedit_cleanup,
184 	.init		=	tcf_skbedit_init,
185 	.walk		=	tcf_generic_walker,
186 };
187 
188 MODULE_AUTHOR("Alexander Duyck, <alexander.h.duyck@intel.com>");
189 MODULE_DESCRIPTION("SKB Editing");
190 MODULE_LICENSE("GPL");
191 
192 static int __init skbedit_init_module(void)
193 {
194 	return tcf_register_action(&act_skbedit_ops);
195 }
196 
197 static void __exit skbedit_cleanup_module(void)
198 {
199 	tcf_unregister_action(&act_skbedit_ops);
200 }
201 
202 module_init(skbedit_init_module);
203 module_exit(skbedit_cleanup_module);
204