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, see <http://www.gnu.org/licenses/>.
  15  *
  16  * Author: Alexander Duyck <alexander.h.duyck@intel.com>
  17  */
  18
  19 #include <linux/module.h>
  20 #include <linux/init.h>
  21 #include <linux/kernel.h>
  22 #include <linux/skbuff.h>
  23 #include <linux/rtnetlink.h>
  24 #include <net/netlink.h>
  25 #include <net/pkt_sched.h>
  26
  27 #include <linux/tc_act/tc_skbedit.h>
  28 #include <net/tc_act/tc_skbedit.h>
  29
  30 #define SKBEDIT_TAB_MASK     15
  31
  32 static int tcf_skbedit(struct sk_buff *skb, const struct tc_action *a,
  33                        struct tcf_result *res)
  34 {
  35         struct tcf_skbedit *d = a->priv;
  36
  37         spin_lock(&d->tcf_lock);
  38         d->tcf_tm.lastuse = jiffies;
  39         bstats_update(&d->tcf_bstats, skb);
  40
  41         if (d->flags & SKBEDIT_F_PRIORITY)
  42                 skb->priority = d->priority;
  43         if (d->flags & SKBEDIT_F_QUEUE_MAPPING &&
  44             skb->dev->real_num_tx_queues > d->queue_mapping)
  45                 skb_set_queue_mapping(skb, d->queue_mapping);
  46         if (d->flags & SKBEDIT_F_MARK)
  47                 skb->mark = d->mark;
  48
  49         spin_unlock(&d->tcf_lock);
  50         return d->tcf_action;
  51 }
  52
  53 static const struct nla_policy skbedit_policy[TCA_SKBEDIT_MAX + 1] = {
  54         [TCA_SKBEDIT_PARMS]             = { .len = sizeof(struct tc_skbedit) },
  55         [TCA_SKBEDIT_PRIORITY]          = { .len = sizeof(u32) },
  56         [TCA_SKBEDIT_QUEUE_MAPPING]     = { .len = sizeof(u16) },
  57         [TCA_SKBEDIT_MARK]              = { .len = sizeof(u32) },
  58 };
  59
  60 static int tcf_skbedit_init(struct net *net, struct nlattr *nla,
  61                             struct nlattr *est, struct tc_action *a,
  62                             int ovr, int bind)
  63 {
  64         struct nlattr *tb[TCA_SKBEDIT_MAX + 1];
  65         struct tc_skbedit *parm;
  66         struct tcf_skbedit *d;
  67         u32 flags = 0, *priority = NULL, *mark = NULL;
  68         u16 *queue_mapping = NULL;
  69         int ret = 0, err;
  70
  71         if (nla == NULL)
  72                 return -EINVAL;
  73
  74         err = nla_parse_nested(tb, TCA_SKBEDIT_MAX, nla, skbedit_policy);
  75         if (err < 0)
  76                 return err;
  77
  78         if (tb[TCA_SKBEDIT_PARMS] == NULL)
  79                 return -EINVAL;
  80
  81         if (tb[TCA_SKBEDIT_PRIORITY] != NULL) {
  82                 flags |= SKBEDIT_F_PRIORITY;
  83                 priority = nla_data(tb[TCA_SKBEDIT_PRIORITY]);
  84         }
  85
  86         if (tb[TCA_SKBEDIT_QUEUE_MAPPING] != NULL) {
  87                 flags |= SKBEDIT_F_QUEUE_MAPPING;
  88                 queue_mapping = nla_data(tb[TCA_SKBEDIT_QUEUE_MAPPING]);
  89         }
  90
  91         if (tb[TCA_SKBEDIT_MARK] != NULL) {
  92                 flags |= SKBEDIT_F_MARK;
  93                 mark = nla_data(tb[TCA_SKBEDIT_MARK]);
  94         }
  95
  96         if (!flags)
  97                 return -EINVAL;
  98
  99         parm = nla_data(tb[TCA_SKBEDIT_PARMS]);
 100
 101         if (!tcf_hash_check(parm->index, a, bind)) {
 102                 ret = tcf_hash_create(parm->index, est, a, sizeof(*d), bind);
 103                 if (ret)
 104                         return ret;
 105
 106                 d = to_skbedit(a);
 107                 ret = ACT_P_CREATED;
 108         } else {
 109                 d = to_skbedit(a);
 110                 if (bind)
 111                         return 0;
 112                 tcf_hash_release(a, bind);
 113                 if (!ovr)
 114                         return -EEXIST;
 115         }
 116
 117         spin_lock_bh(&d->tcf_lock);
 118
 119         d->flags = flags;
 120         if (flags & SKBEDIT_F_PRIORITY)
 121                 d->priority = *priority;
 122         if (flags & SKBEDIT_F_QUEUE_MAPPING)
 123                 d->queue_mapping = *queue_mapping;
 124         if (flags & SKBEDIT_F_MARK)
 125                 d->mark = *mark;
 126
 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(a);
 133         return ret;
 134 }
 135
 136 static int tcf_skbedit_dump(struct sk_buff *skb, struct tc_action *a,
 137                             int bind, int ref)
 138 {
 139         unsigned char *b = skb_tail_pointer(skb);
 140         struct tcf_skbedit *d = a->priv;
 141         struct tc_skbedit opt = {
 142                 .index   = d->tcf_index,
 143                 .refcnt  = d->tcf_refcnt - ref,
 144                 .bindcnt = d->tcf_bindcnt - bind,
 145                 .action  = d->tcf_action,
 146         };
 147         struct tcf_t t;
 148
 149         if (nla_put(skb, TCA_SKBEDIT_PARMS, sizeof(opt), &opt))
 150                 goto nla_put_failure;
 151         if ((d->flags & SKBEDIT_F_PRIORITY) &&
 152             nla_put(skb, TCA_SKBEDIT_PRIORITY, sizeof(d->priority),
 153                     &d->priority))
 154                 goto nla_put_failure;
 155         if ((d->flags & SKBEDIT_F_QUEUE_MAPPING) &&
 156             nla_put(skb, TCA_SKBEDIT_QUEUE_MAPPING,
 157                     sizeof(d->queue_mapping), &d->queue_mapping))
 158                 goto nla_put_failure;
 159         if ((d->flags & SKBEDIT_F_MARK) &&
 160             nla_put(skb, TCA_SKBEDIT_MARK, sizeof(d->mark),
 161                     &d->mark))
 162                 goto nla_put_failure;
 163         t.install = jiffies_to_clock_t(jiffies - d->tcf_tm.install);
 164         t.lastuse = jiffies_to_clock_t(jiffies - d->tcf_tm.lastuse);
 165         t.expires = jiffies_to_clock_t(d->tcf_tm.expires);
 166         if (nla_put(skb, TCA_SKBEDIT_TM, sizeof(t), &t))
 167                 goto nla_put_failure;
 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         .type           =       TCA_ACT_SKBEDIT,
 178         .owner          =       THIS_MODULE,
 179         .act            =       tcf_skbedit,
 180         .dump           =       tcf_skbedit_dump,
 181         .init           =       tcf_skbedit_init,
 182 };
 183
 184 MODULE_AUTHOR("Alexander Duyck, <alexander.h.duyck@intel.com>");
 185 MODULE_DESCRIPTION("SKB Editing");
 186 MODULE_LICENSE("GPL");
 187
 188 static int __init skbedit_init_module(void)
 189 {
 190         return tcf_register_action(&act_skbedit_ops, SKBEDIT_TAB_MASK);
 191 }
 192
 193 static void __exit skbedit_cleanup_module(void)
 194 {
 195         tcf_unregister_action(&act_skbedit_ops);
 196 }
 197
 198 module_init(skbedit_init_module);
 199 module_exit(skbedit_cleanup_module);