Merge branch 'for-2.6.28' of git://linux-nfs.org/~bfields/linux
[linux-2.6] / net / sched / act_skbedit.c
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 (unlikely(!pc))
108                         return -ENOMEM;
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);