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);