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         if (d->flags & SKBEDIT_F_MARK)
  58                 skb->mark = d->mark;
  59
  60         spin_unlock(&d->tcf_lock);
  61         return d->tcf_action;
  62 }
  63
  64 static const struct nla_policy skbedit_policy[TCA_SKBEDIT_MAX + 1] = {
  65         [TCA_SKBEDIT_PARMS]             = { .len = sizeof(struct tc_skbedit) },
  66         [TCA_SKBEDIT_PRIORITY]          = { .len = sizeof(u32) },
  67         [TCA_SKBEDIT_QUEUE_MAPPING]     = { .len = sizeof(u16) },
  68         [TCA_SKBEDIT_MARK]              = { .len = sizeof(u32) },
  69 };
  70
  71 static int tcf_skbedit_init(struct nlattr *nla, struct nlattr *est,
  72                          struct tc_action *a, int ovr, int bind)
  73 {
  74         struct nlattr *tb[TCA_SKBEDIT_MAX + 1];
  75         struct tc_skbedit *parm;
  76         struct tcf_skbedit *d;
  77         struct tcf_common *pc;
  78         u32 flags = 0, *priority = NULL, *mark = NULL;
  79         u16 *queue_mapping = NULL;
  80         int ret = 0, err;
  81
  82         if (nla == NULL)
  83                 return -EINVAL;
  84
  85         err = nla_parse_nested(tb, TCA_SKBEDIT_MAX, nla, skbedit_policy);
  86         if (err < 0)
  87                 return err;
  88
  89         if (tb[TCA_SKBEDIT_PARMS] == NULL)
  90                 return -EINVAL;
  91
  92         if (tb[TCA_SKBEDIT_PRIORITY] != NULL) {
  93                 flags |= SKBEDIT_F_PRIORITY;
  94                 priority = nla_data(tb[TCA_SKBEDIT_PRIORITY]);
  95         }
  96
  97         if (tb[TCA_SKBEDIT_QUEUE_MAPPING] != NULL) {
  98                 flags |= SKBEDIT_F_QUEUE_MAPPING;
  99                 queue_mapping = nla_data(tb[TCA_SKBEDIT_QUEUE_MAPPING]);
 100         }
 101
 102         if (tb[TCA_SKBEDIT_MARK] != NULL) {
 103                 flags |= SKBEDIT_F_MARK;
 104                 mark = nla_data(tb[TCA_SKBEDIT_MARK]);
 105         }
 106
 107         if (!flags)
 108                 return -EINVAL;
 109
 110         parm = nla_data(tb[TCA_SKBEDIT_PARMS]);
 111
 112         pc = tcf_hash_check(parm->index, a, bind, &skbedit_hash_info);
 113         if (!pc) {
 114                 pc = tcf_hash_create(parm->index, est, a, sizeof(*d), bind,
 115                                      &skbedit_idx_gen, &skbedit_hash_info);
 116                 if (IS_ERR(pc))
 117                     return PTR_ERR(pc);
 118
 119                 d = to_skbedit(pc);
 120                 ret = ACT_P_CREATED;
 121         } else {
 122                 d = to_skbedit(pc);
 123                 if (!ovr) {
 124                         tcf_hash_release(pc, bind, &skbedit_hash_info);
 125                         return -EEXIST;
 126                 }
 127         }
 128
 129         spin_lock_bh(&d->tcf_lock);
 130
 131         d->flags = flags;
 132         if (flags & SKBEDIT_F_PRIORITY)
 133                 d->priority = *priority;
 134         if (flags & SKBEDIT_F_QUEUE_MAPPING)
 135                 d->queue_mapping = *queue_mapping;
 136         if (flags & SKBEDIT_F_MARK)
 137                 d->mark = *mark;
 138
 139         d->tcf_action = parm->action;
 140
 141         spin_unlock_bh(&d->tcf_lock);
 142
 143         if (ret == ACT_P_CREATED)
 144                 tcf_hash_insert(pc, &skbedit_hash_info);
 145         return ret;
 146 }
 147
 148 static inline int tcf_skbedit_cleanup(struct tc_action *a, int bind)
 149 {
 150         struct tcf_skbedit *d = a->priv;
 151
 152         if (d)
 153                 return tcf_hash_release(&d->common, bind, &skbedit_hash_info);
 154         return 0;
 155 }
 156
 157 static inline int tcf_skbedit_dump(struct sk_buff *skb, struct tc_action *a,
 158                                 int bind, int ref)
 159 {
 160         unsigned char *b = skb_tail_pointer(skb);
 161         struct tcf_skbedit *d = a->priv;
 162         struct tc_skbedit opt = {
 163                 .index   = d->tcf_index,
 164                 .refcnt  = d->tcf_refcnt - ref,
 165                 .bindcnt = d->tcf_bindcnt - bind,
 166                 .action  = d->tcf_action,
 167         };
 168         struct tcf_t t;
 169
 170         NLA_PUT(skb, TCA_SKBEDIT_PARMS, sizeof(opt), &opt);
 171         if (d->flags & SKBEDIT_F_PRIORITY)
 172                 NLA_PUT(skb, TCA_SKBEDIT_PRIORITY, sizeof(d->priority),
 173                         &d->priority);
 174         if (d->flags & SKBEDIT_F_QUEUE_MAPPING)
 175                 NLA_PUT(skb, TCA_SKBEDIT_QUEUE_MAPPING,
 176                         sizeof(d->queue_mapping), &d->queue_mapping);
 177         if (d->flags & SKBEDIT_F_MARK)
 178                 NLA_PUT(skb, TCA_SKBEDIT_MARK, sizeof(d->mark),
 179                         &d->mark);
 180         t.install = jiffies_to_clock_t(jiffies - d->tcf_tm.install);
 181         t.lastuse = jiffies_to_clock_t(jiffies - d->tcf_tm.lastuse);
 182         t.expires = jiffies_to_clock_t(d->tcf_tm.expires);
 183         NLA_PUT(skb, TCA_SKBEDIT_TM, sizeof(t), &t);
 184         return skb->len;
 185
 186 nla_put_failure:
 187         nlmsg_trim(skb, b);
 188         return -1;
 189 }
 190
 191 static struct tc_action_ops act_skbedit_ops = {
 192         .kind           =       "skbedit",
 193         .hinfo          =       &skbedit_hash_info,
 194         .type           =       TCA_ACT_SKBEDIT,
 195         .capab          =       TCA_CAP_NONE,
 196         .owner          =       THIS_MODULE,
 197         .act            =       tcf_skbedit,
 198         .dump           =       tcf_skbedit_dump,
 199         .cleanup        =       tcf_skbedit_cleanup,
 200         .init           =       tcf_skbedit_init,
 201         .walk           =       tcf_generic_walker,
 202 };
 203
 204 MODULE_AUTHOR("Alexander Duyck, <alexander.h.duyck@intel.com>");
 205 MODULE_DESCRIPTION("SKB Editing");
 206 MODULE_LICENSE("GPL");
 207
 208 static int __init skbedit_init_module(void)
 209 {
 210         return tcf_register_action(&act_skbedit_ops);
 211 }
 212
 213 static void __exit skbedit_cleanup_module(void)
 214 {
 215         tcf_unregister_action(&act_skbedit_ops);
 216 }
 217
 218 module_init(skbedit_init_module);
 219 module_exit(skbedit_cleanup_module);