[PKT_SCHED]: Introduce simple actions.

And provide an example simply action in order to
demonstrate usage.

Signed-off-by: Jamal Hadi Salim <hadi@cyberus.ca>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/sched/Kconfig

@@ -506,3 +506,13 @@ config NET_CLS_POLICE
 	  Say Y to support traffic policing (bandwidth limits).  Needed for
 	  ingress and egress rate limiting.
 
+config NET_ACT_SIMP
+        tristate "Simple action"
+        depends on NET_CLS_ACT
+        ---help---
+        You must have new iproute2 to use this feature.
+        This adds a very simple action for demonstration purposes
+	The idea is to give action authors a basic example to look at.
+	All this action will do is print on the console the configured
+	policy string followed by _ then packet count.
+

net/sched/Makefile

@@ -6,13 +6,14 @@ obj-y	:= sch_generic.o
 
 obj-$(CONFIG_NET_SCHED)		+= sch_api.o sch_fifo.o
 obj-$(CONFIG_NET_CLS)		+= cls_api.o
-obj-$(CONFIG_NET_CLS_ACT)       += act_api.o
+obj-$(CONFIG_NET_CLS_ACT)	+= act_api.o
 obj-$(CONFIG_NET_ACT_POLICE)	+= police.o
 obj-$(CONFIG_NET_CLS_POLICE)	+= police.o
-obj-$(CONFIG_NET_ACT_GACT)      += gact.o
-obj-$(CONFIG_NET_ACT_MIRRED)    += mirred.o
-obj-$(CONFIG_NET_ACT_IPT)       += ipt.o
-obj-$(CONFIG_NET_ACT_PEDIT)     += pedit.o
+obj-$(CONFIG_NET_ACT_GACT)	+= gact.o
+obj-$(CONFIG_NET_ACT_MIRRED)	+= mirred.o
+obj-$(CONFIG_NET_ACT_IPT)	+= ipt.o
+obj-$(CONFIG_NET_ACT_PEDIT)	+= pedit.o
+obj-$(CONFIG_NET_ACT_SIMP)	+= simple.o
 obj-$(CONFIG_NET_SCH_CBQ)	+= sch_cbq.o
 obj-$(CONFIG_NET_SCH_HTB)	+= sch_htb.o
 obj-$(CONFIG_NET_SCH_HPFQ)	+= sch_hpfq.o

net/sched/simple.c

@@ -0,0 +1,107 @@
+/*
+ * net/sched/simp.c	Simple example of an action
+ *
+ *		This program is free software; you can redistribute it and/or
+ *		modify it under the terms of the GNU General Public License
+ *		as published by the Free Software Foundation; either version
+ *		2 of the License, or (at your option) any later version.
+ *
+ * Authors:	Jamal Hadi Salim (2005)
+ *
+ */
+
+#include <asm/uaccess.h>
+#include <asm/system.h>
+#include <asm/bitops.h>
+#include <linux/config.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/string.h>
+#include <linux/mm.h>
+#include <linux/socket.h>
+#include <linux/sockios.h>
+#include <linux/in.h>
+#include <linux/errno.h>
+#include <linux/interrupt.h>
+#include <linux/netdevice.h>
+#include <linux/skbuff.h>
+#include <linux/rtnetlink.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/proc_fs.h>
+#include <net/sock.h>
+#include <net/pkt_sched.h>
+
+#define TCA_ACT_SIMP 22
+
+/* XXX: Hide all these common elements under some macro 
+ * probably
+*/
+#include <linux/tc_act/tc_defact.h>
+#include <net/tc_act/tc_defact.h>
+
+/* use generic hash table with 8 buckets */
+#define MY_TAB_SIZE     8
+#define MY_TAB_MASK     (MY_TAB_SIZE - 1)
+static u32 idx_gen;
+static struct tcf_defact *tcf_simp_ht[MY_TAB_SIZE];
+static DEFINE_RWLOCK(simp_lock);
+
+/* override the defaults */
+#define tcf_st		tcf_defact
+#define tc_st		tc_defact
+#define tcf_t_lock	simp_lock
+#define tcf_ht		tcf_simp_ht
+
+#define CONFIG_NET_ACT_INIT 1
+#include <net/pkt_act.h>
+#include <net/act_generic.h>
+
+static int tcf_simp(struct sk_buff **pskb, struct tc_action *a)
+{
+	struct sk_buff *skb = *pskb;
+	struct tcf_defact *p = PRIV(a, defact);
+
+	spin_lock(&p->lock);
+	p->tm.lastuse = jiffies;
+	p->bstats.bytes += skb->len;
+	p->bstats.packets++;
+
+	/* print policy string followed by _ then packet count 
+	 * Example if this was the 3rd packet and the string was "hello" 
+	 * then it would look like "hello_3" (without quotes) 
+	 **/
+	printk("simple: %s_%d\n", (char *)p->defdata, p->bstats.packets);
+	spin_unlock(&p->lock);
+	return p->action;
+}
+
+static struct tc_action_ops act_simp_ops = {
+	.kind = "simple",
+	.type = TCA_ACT_SIMP,
+	.capab = TCA_CAP_NONE,
+	.owner = THIS_MODULE,
+	.act = tcf_simp,
+	tca_use_default_ops
+};
+
+MODULE_AUTHOR("Jamal Hadi Salim(2005)");
+MODULE_DESCRIPTION("Simple example action");
+MODULE_LICENSE("GPL");
+
+static int __init simp_init_module(void)
+{
+	int ret = tcf_register_action(&act_simp_ops);
+	if (!ret)
+		printk("Simple TC action Loaded\n");
+	return ret;
+}
+
+static void __exit simp_cleanup_module(void)
+{
+	tcf_unregister_action(&act_simp_ops);
+}
+
+module_init(simp_init_module);
+module_exit(simp_cleanup_module);