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, const 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         bstats_update(&d->tcf_bstats, skb);
  50
  51         if (d->flags & SKBEDIT_F_PRIORITY)
  52                 skb->priority = d->priority;
  53         if (d->flags & SKBEDIT_F_QUEUE_MAPPING &&
  54             skb->dev->real_num_tx_queues > d->queue_mapping)
  55                 skb_set_queue_mapping(skb, d->queue_mapping);
  56         if (d->flags & SKBEDIT_F_MARK)
  57                 skb->mark = d->mark;
  58
  59         spin_unlock(&d->tcf_lock);
  60         return d->tcf_action;
  61 }
  62
  63 static const struct nla_policy skbedit_policy[TCA_SKBEDIT_MAX + 1] = {
  64         [TCA_SKBEDIT_PARMS]             = { .len = sizeof(struct tc_skbedit) },
  65         [TCA_SKBEDIT_PRIORITY]          = { .len = sizeof(u32) },
  66         [TCA_SKBEDIT_QUEUE_MAPPING]     = { .len = sizeof(u16) },
  67         [TCA_SKBEDIT_MARK]              = { .len = sizeof(u32) },
  68 };
  69
  70 static int tcf_skbedit_init(struct nlattr *nla, struct nlattr *est,
  71                          struct tc_action *a, int ovr, int bind)
  72 {
  73         struct nlattr *tb[TCA_SKBEDIT_MAX + 1];
  74         struct tc_skbedit *parm;
  75         struct tcf_skbedit *d;
  76         struct tcf_common *pc;
  77         u32 flags = 0, *priority = NULL, *mark = NULL;
  78         u16 *queue_mapping = NULL;
  79         int ret = 0, err;
  80
  81         if (nla == NULL)
  82                 return -EINVAL;
  83
  84         err = nla_parse_nested(tb, TCA_SKBEDIT_MAX, nla, skbedit_policy);
  85         if (err < 0)
  86                 return err;
  87
  88         if (tb[TCA_SKBEDIT_PARMS] == NULL)
  89                 return -EINVAL;
  90
  91         if (tb[TCA_SKBEDIT_PRIORITY] != NULL) {
  92                 flags |= SKBEDIT_F_PRIORITY;
  93                 priority = nla_data(tb[TCA_SKBEDIT_PRIORITY]);
  94         }
  95
  96         if (tb[TCA_SKBEDIT_QUEUE_MAPPING] != NULL) {
  97                 flags |= SKBEDIT_F_QUEUE_MAPPING;
  98                 queue_mapping = nla_data(tb[TCA_SKBEDIT_QUEUE_MAPPING]);
  99         }
 100
 101         if (tb[TCA_SKBEDIT_MARK] != NULL) {
 102                 flags |= SKBEDIT_F_MARK;
 103                 mark = nla_data(tb[TCA_SKBEDIT_MARK]);
 104         }
 105
 106         if (!flags)
 107                 return -EINVAL;
 108
 109         parm = nla_data(tb[TCA_SKBEDIT_PARMS]);
 110
 111         pc = tcf_hash_check(parm->index, a, bind, &skbedit_hash_info);
 112         if (!pc) {
 113                 pc = tcf_hash_create(parm->index, est, a, sizeof(*d), bind,
 114                                      &skbedit_idx_gen, &skbedit_hash_info);
 115                 if (IS_ERR(pc))
 116                         return PTR_ERR(pc);
 117
 118                 d = to_skbedit(pc);
 119                 ret = ACT_P_CREATED;
 120         } else {
 121                 d = to_skbedit(pc);
 122                 if (!ovr) {
 123                         tcf_hash_release(pc, bind, &skbedit_hash_info);
 124                         return -EEXIST;
 125                 }
 126         }
 127
 128         spin_lock_bh(&d->tcf_lock);
 129
 130         d->flags = flags;
 131         if (flags & SKBEDIT_F_PRIORITY)
 132                 d->priority = *priority;
 133         if (flags & SKBEDIT_F_QUEUE_MAPPING)
 134                 d->queue_mapping = *queue_mapping;
 135         if (flags & SKBEDIT_F_MARK)
 136                 d->mark = *mark;
 137
 138         d->tcf_action = parm->action;
 139
 140         spin_unlock_bh(&d->tcf_lock);
 141
 142         if (ret == ACT_P_CREATED)
 143                 tcf_hash_insert(pc, &skbedit_hash_info);
 144         return ret;
 145 }
 146
 147 static int tcf_skbedit_cleanup(struct tc_action *a, int bind)
 148 {
 149         struct tcf_skbedit *d = a->priv;
 150
 151         if (d)
 152                 return tcf_hash_release(&d->common, bind, &skbedit_hash_info);
 153         return 0;
 154 }
 155
 156 static int tcf_skbedit_dump(struct sk_buff *skb, struct tc_action *a,
 157                             int bind, int ref)
 158 {
 159         unsigned char *b = skb_tail_pointer(skb);
 160         struct tcf_skbedit *d = a->priv;
 161         struct tc_skbedit opt = {
 162                 .index   = d->tcf_index,
 163                 .refcnt  = d->tcf_refcnt - ref,
 164                 .bindcnt = d->tcf_bindcnt - bind,
 165                 .action  = d->tcf_action,
 166         };
 167         struct tcf_t t;
 168
 169         NLA_PUT(skb, TCA_SKBEDIT_PARMS, sizeof(opt), &opt);
 170         if (d->flags & SKBEDIT_F_PRIORITY)
 171                 NLA_PUT(skb, TCA_SKBEDIT_PRIORITY, sizeof(d->priority),
 172                         &d->priority);
 173         if (d->flags & SKBEDIT_F_QUEUE_MAPPING)
 174                 NLA_PUT(skb, TCA_SKBEDIT_QUEUE_MAPPING,
 175                         sizeof(d->queue_mapping), &d->queue_mapping);
 176         if (d->flags & SKBEDIT_F_MARK)
 177                 NLA_PUT(skb, TCA_SKBEDIT_MARK, sizeof(d->mark),
 178                         &d->mark);
 179         t.install = jiffies_to_clock_t(jiffies - d->tcf_tm.install);
 180         t.lastuse = jiffies_to_clock_t(jiffies - d->tcf_tm.lastuse);
 181         t.expires = jiffies_to_clock_t(d->tcf_tm.expires);
 182         NLA_PUT(skb, TCA_SKBEDIT_TM, sizeof(t), &t);
 183         return skb->len;
 184
 185 nla_put_failure:
 186         nlmsg_trim(skb, b);
 187         return -1;
 188 }
 189
 190 static struct tc_action_ops act_skbedit_ops = {
 191         .kind           =       "skbedit",
 192         .hinfo          =       &skbedit_hash_info,
 193         .type           =       TCA_ACT_SKBEDIT,
 194         .capab          =       TCA_CAP_NONE,
 195         .owner          =       THIS_MODULE,
 196         .act            =       tcf_skbedit,
 197         .dump           =       tcf_skbedit_dump,
 198         .cleanup        =       tcf_skbedit_cleanup,
 199         .init           =       tcf_skbedit_init,
 200         .walk           =       tcf_generic_walker,
 201 };
 202
 203 MODULE_AUTHOR("Alexander Duyck, <alexander.h.duyck@intel.com>");
 204 MODULE_DESCRIPTION("SKB Editing");
 205 MODULE_LICENSE("GPL");
 206
 207 static int __init skbedit_init_module(void)
 208 {
 209         return tcf_register_action(&act_skbedit_ops);
 210 }
 211
 212 static void __exit skbedit_cleanup_module(void)
 213 {
 214         tcf_unregister_action(&act_skbedit_ops);
 215 }
 216
 217 module_init(skbedit_init_module);
 218 module_exit(skbedit_cleanup_module);