net/sched/simple.c

   1 /*
   2  * net/sched/simp.c     Simple example of an action
   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  * Authors:     Jamal Hadi Salim (2005)
  10  *
  11  */
  12
  13 #include <linux/config.h>
  14 #include <linux/module.h>
  15 #include <linux/init.h>
  16 #include <linux/kernel.h>
  17 #include <linux/netdevice.h>
  18 #include <linux/skbuff.h>
  19 #include <linux/rtnetlink.h>
  20 #include <net/pkt_sched.h>
  21
  22 #define TCA_ACT_SIMP 22
  23
  24 /* XXX: Hide all these common elements under some macro
  25  * probably
  26 */
  27 #include <linux/tc_act/tc_defact.h>
  28 #include <net/tc_act/tc_defact.h>
  29
  30 /* use generic hash table with 8 buckets */
  31 #define MY_TAB_SIZE     8
  32 #define MY_TAB_MASK     (MY_TAB_SIZE - 1)
  33 static u32 idx_gen;
  34 static struct tcf_defact *tcf_simp_ht[MY_TAB_SIZE];
  35 static DEFINE_RWLOCK(simp_lock);
  36
  37 /* override the defaults */
  38 #define tcf_st          tcf_defact
  39 #define tc_st           tc_defact
  40 #define tcf_t_lock      simp_lock
  41 #define tcf_ht          tcf_simp_ht
  42
  43 #define CONFIG_NET_ACT_INIT 1
  44 #include <net/pkt_act.h>
  45 #include <net/act_generic.h>
  46
  47 static int tcf_simp(struct sk_buff **pskb, struct tc_action *a)
  48 {
  49         struct sk_buff *skb = *pskb;
  50         struct tcf_defact *p = PRIV(a, defact);
  51
  52         spin_lock(&p->lock);
  53         p->tm.lastuse = jiffies;
  54         p->bstats.bytes += skb->len;
  55         p->bstats.packets++;
  56
  57         /* print policy string followed by _ then packet count
  58          * Example if this was the 3rd packet and the string was "hello"
  59          * then it would look like "hello_3" (without quotes)
  60          **/
  61         printk("simple: %s_%d\n", (char *)p->defdata, p->bstats.packets);
  62         spin_unlock(&p->lock);
  63         return p->action;
  64 }
  65
  66 static struct tc_action_ops act_simp_ops = {
  67         .kind = "simple",
  68         .type = TCA_ACT_SIMP,
  69         .capab = TCA_CAP_NONE,
  70         .owner = THIS_MODULE,
  71         .act = tcf_simp,
  72         tca_use_default_ops
  73 };
  74
  75 MODULE_AUTHOR("Jamal Hadi Salim(2005)");
  76 MODULE_DESCRIPTION("Simple example action");
  77 MODULE_LICENSE("GPL");
  78
  79 static int __init simp_init_module(void)
  80 {
  81         int ret = tcf_register_action(&act_simp_ops);
  82         if (!ret)
  83                 printk("Simple TC action Loaded\n");
  84         return ret;
  85 }
  86
  87 static void __exit simp_cleanup_module(void)
  88 {
  89         tcf_unregister_action(&act_simp_ops);
  90 }
  91
  92 module_init(simp_init_module);
  93 module_exit(simp_cleanup_module);