Pileus Git - ~andy/linux/blob - net/sched/act_gact.c

   1 /*
   2  * net/sched/gact.c     Generic actions
   3  *
   4  *              This program is free software; you can redistribute it and/or
   5  *              modify it under the terms of the GNU General Public License
   6  *              as published by the Free Software Foundation; either version
   7  *              2 of the License, or (at your option) any later version.
   8  *
   9  * copyright    Jamal Hadi Salim (2002-4)
  10  *
  11  */
  12
  13 #include <linux/types.h>
  14 #include <linux/kernel.h>
  15 #include <linux/string.h>
  16 #include <linux/errno.h>
  17 #include <linux/skbuff.h>
  18 #include <linux/rtnetlink.h>
  19 #include <linux/module.h>
  20 #include <linux/init.h>
  21 #include <net/netlink.h>
  22 #include <net/pkt_sched.h>
  23 #include <linux/tc_act/tc_gact.h>
  24 #include <net/tc_act/tc_gact.h>
  25
  26 #define GACT_TAB_MASK   15
  27 static u32 gact_idx_gen;
  28 static struct tcf_hashinfo gact_hash_info;
  29
  30 #ifdef CONFIG_GACT_PROB
  31 static int gact_net_rand(struct tcf_gact *gact)
  32 {
  33         if (!gact->tcfg_pval || net_random() % gact->tcfg_pval)
  34                 return gact->tcf_action;
  35         return gact->tcfg_paction;
  36 }
  37
  38 static int gact_determ(struct tcf_gact *gact)
  39 {
  40         if (!gact->tcfg_pval || gact->tcf_bstats.packets % gact->tcfg_pval)
  41                 return gact->tcf_action;
  42         return gact->tcfg_paction;
  43 }
  44
  45 typedef int (*g_rand)(struct tcf_gact *gact);
  46 static g_rand gact_rand[MAX_RAND] = { NULL, gact_net_rand, gact_determ };
  47 #endif /* CONFIG_GACT_PROB */
  48
  49 static const struct nla_policy gact_policy[TCA_GACT_MAX + 1] = {
  50         [TCA_GACT_PARMS]        = { .len = sizeof(struct tc_gact) },
  51         [TCA_GACT_PROB]         = { .len = sizeof(struct tc_gact_p) },
  52 };
  53
  54 static int tcf_gact_init(struct net *net, struct nlattr *nla,
  55                          struct nlattr *est, struct tc_action *a,
  56                          int ovr, int bind)
  57 {
  58         struct nlattr *tb[TCA_GACT_MAX + 1];
  59         struct tc_gact *parm;
  60         struct tcf_gact *gact;
  61         struct tcf_common *pc;
  62         int ret = 0;
  63         int err;
  64 #ifdef CONFIG_GACT_PROB
  65         struct tc_gact_p *p_parm = NULL;
  66 #endif
  67
  68         if (nla == NULL)
  69                 return -EINVAL;
  70
  71         err = nla_parse_nested(tb, TCA_GACT_MAX, nla, gact_policy);
  72         if (err < 0)
  73                 return err;
  74
  75         if (tb[TCA_GACT_PARMS] == NULL)
  76                 return -EINVAL;
  77         parm = nla_data(tb[TCA_GACT_PARMS]);
  78
  79 #ifndef CONFIG_GACT_PROB
  80         if (tb[TCA_GACT_PROB] != NULL)
  81                 return -EOPNOTSUPP;
  82 #else
  83         if (tb[TCA_GACT_PROB]) {
  84                 p_parm = nla_data(tb[TCA_GACT_PROB]);
  85                 if (p_parm->ptype >= MAX_RAND)
  86                         return -EINVAL;
  87         }
  88 #endif
  89
  90         pc = tcf_hash_check(parm->index, a, bind, &gact_hash_info);
  91         if (!pc) {
  92                 pc = tcf_hash_create(parm->index, est, a, sizeof(*gact),
  93                                      bind, &gact_idx_gen, &gact_hash_info);
  94                 if (IS_ERR(pc))
  95                         return PTR_ERR(pc);
  96                 ret = ACT_P_CREATED;
  97         } else {
  98                 if (bind)/* dont override defaults */
  99                         return 0;
 100                 tcf_hash_release(pc, bind, &gact_hash_info);
 101                 if (!ovr)
 102                         return -EEXIST;
 103         }
 104
 105         gact = to_gact(pc);
 106
 107         spin_lock_bh(&gact->tcf_lock);
 108         gact->tcf_action = parm->action;
 109 #ifdef CONFIG_GACT_PROB
 110         if (p_parm) {
 111                 gact->tcfg_paction = p_parm->paction;
 112                 gact->tcfg_pval    = p_parm->pval;
 113                 gact->tcfg_ptype   = p_parm->ptype;
 114         }
 115 #endif
 116         spin_unlock_bh(&gact->tcf_lock);
 117         if (ret == ACT_P_CREATED)
 118                 tcf_hash_insert(pc, &gact_hash_info);
 119         return ret;
 120 }
 121
 122 static int tcf_gact_cleanup(struct tc_action *a, int bind)
 123 {
 124         struct tcf_gact *gact = a->priv;
 125
 126         if (gact)
 127                 return tcf_hash_release(&gact->common, bind, &gact_hash_info);
 128         return 0;
 129 }
 130
 131 static int tcf_gact(struct sk_buff *skb, const struct tc_action *a,
 132                     struct tcf_result *res)
 133 {
 134         struct tcf_gact *gact = a->priv;
 135         int action = TC_ACT_SHOT;
 136
 137         spin_lock(&gact->tcf_lock);
 138 #ifdef CONFIG_GACT_PROB
 139         if (gact->tcfg_ptype)
 140                 action = gact_rand[gact->tcfg_ptype](gact);
 141         else
 142                 action = gact->tcf_action;
 143 #else
 144         action = gact->tcf_action;
 145 #endif
 146         gact->tcf_bstats.bytes += qdisc_pkt_len(skb);
 147         gact->tcf_bstats.packets++;
 148         if (action == TC_ACT_SHOT)
 149                 gact->tcf_qstats.drops++;
 150         gact->tcf_tm.lastuse = jiffies;
 151         spin_unlock(&gact->tcf_lock);
 152
 153         return action;
 154 }
 155
 156 static int tcf_gact_dump(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
 157 {
 158         unsigned char *b = skb_tail_pointer(skb);
 159         struct tcf_gact *gact = a->priv;
 160         struct tc_gact opt = {
 161                 .index   = gact->tcf_index,
 162                 .refcnt  = gact->tcf_refcnt - ref,
 163                 .bindcnt = gact->tcf_bindcnt - bind,
 164                 .action  = gact->tcf_action,
 165         };
 166         struct tcf_t t;
 167
 168         if (nla_put(skb, TCA_GACT_PARMS, sizeof(opt), &opt))
 169                 goto nla_put_failure;
 170 #ifdef CONFIG_GACT_PROB
 171         if (gact->tcfg_ptype) {
 172                 struct tc_gact_p p_opt = {
 173                         .paction = gact->tcfg_paction,
 174                         .pval    = gact->tcfg_pval,
 175                         .ptype   = gact->tcfg_ptype,
 176                 };
 177
 178                 if (nla_put(skb, TCA_GACT_PROB, sizeof(p_opt), &p_opt))
 179                         goto nla_put_failure;
 180         }
 181 #endif
 182         t.install = jiffies_to_clock_t(jiffies - gact->tcf_tm.install);
 183         t.lastuse = jiffies_to_clock_t(jiffies - gact->tcf_tm.lastuse);
 184         t.expires = jiffies_to_clock_t(gact->tcf_tm.expires);
 185         if (nla_put(skb, TCA_GACT_TM, sizeof(t), &t))
 186                 goto nla_put_failure;
 187         return skb->len;
 188
 189 nla_put_failure:
 190         nlmsg_trim(skb, b);
 191         return -1;
 192 }
 193
 194 static struct tc_action_ops act_gact_ops = {
 195         .kind           =       "gact",
 196         .hinfo          =       &gact_hash_info,
 197         .type           =       TCA_ACT_GACT,
 198         .capab          =       TCA_CAP_NONE,
 199         .owner          =       THIS_MODULE,
 200         .act            =       tcf_gact,
 201         .dump           =       tcf_gact_dump,
 202         .cleanup        =       tcf_gact_cleanup,
 203         .init           =       tcf_gact_init,
 204 };
 205
 206 MODULE_AUTHOR("Jamal Hadi Salim(2002-4)");
 207 MODULE_DESCRIPTION("Generic Classifier actions");
 208 MODULE_LICENSE("GPL");
 209
 210 static int __init gact_init_module(void)
 211 {
 212         int err = tcf_hashinfo_init(&gact_hash_info, GACT_TAB_MASK);
 213         if (err)
 214                 return err;
 215 #ifdef CONFIG_GACT_PROB
 216         pr_info("GACT probability on\n");
 217 #else
 218         pr_info("GACT probability NOT on\n");
 219 #endif
 220         return tcf_register_action(&act_gact_ops);
 221 }
 222
 223 static void __exit gact_cleanup_module(void)
 224 {
 225         tcf_unregister_action(&act_gact_ops);
 226         tcf_hashinfo_destroy(&gact_hash_info);
 227 }
 228
 229 module_init(gact_init_module);
 230 module_exit(gact_cleanup_module);