/* * 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 (2005-8) * */ #include <linux/module.h> #include <linux/init.h> #include <linux/kernel.h> #include <linux/skbuff.h> #include <linux/rtnetlink.h> #include <net/netlink.h> #include <net/pkt_sched.h> #define TCA_ACT_SIMP 22 #include <linux/tc_act/tc_defact.h> #include <net/tc_act/tc_defact.h> #define SIMP_TAB_MASK 7 static struct tcf_common *tcf_simp_ht[SIMP_TAB_MASK + 1]; static u32 simp_idx_gen; static DEFINE_RWLOCK(simp_lock); static struct tcf_hashinfo simp_hash_info = { .htab = tcf_simp_ht, .hmask = SIMP_TAB_MASK, .lock = &simp_lock, }; #define SIMP_MAX_DATA 32 static int tcf_simp(struct sk_buff *skb, struct tc_action *a, struct tcf_result *res) { struct tcf_defact *d = a->priv; spin_lock(&d->tcf_lock); d->tcf_tm.lastuse = jiffies; d->tcf_bstats.bytes += skb->len; d->tcf_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 *)d->tcfd_defdata, d->tcf_bstats.packets); spin_unlock(&d->tcf_lock); return d->tcf_action; } static int tcf_simp_release(struct tcf_defact *d, int bind) { int ret = 0; if (d) { if (bind) d->tcf_bindcnt--; d->tcf_refcnt--; if (d->tcf_bindcnt <= 0 && d->tcf_refcnt <= 0) { kfree(d->tcfd_defdata); tcf_hash_destroy(&d->common, &simp_hash_info); ret = 1; } } return ret; } static int alloc_defdata(struct tcf_defact *d, char *defdata) { d->tcfd_defdata = kstrndup(defdata, SIMP_MAX_DATA, GFP_KERNEL); if (unlikely(!d->tcfd_defdata)) return -ENOMEM; return 0; } static void reset_policy(struct tcf_defact *d, char *defdata, struct tc_defact *p) { spin_lock_bh(&d->tcf_lock); d->tcf_action = p->action; memset(d->tcfd_defdata, 0, SIMP_MAX_DATA); strlcpy(d->tcfd_defdata, defdata, SIMP_MAX_DATA); spin_unlock_bh(&d->tcf_lock); } static const struct nla_policy simple_policy[TCA_DEF_MAX + 1] = { [TCA_DEF_PARMS] = { .len = sizeof(struct tc_defact) }, [TCA_DEF_DATA] = { .type = NLA_STRING, .len = SIMP_MAX_DATA }, }; static int tcf_simp_init(struct nlattr *nla, struct nlattr *est, struct tc_action *a, int ovr, int bind) { struct nlattr *tb[TCA_DEF_MAX + 1]; struct tc_defact *parm; struct tcf_defact *d; struct tcf_common *pc; char *defdata; int ret = 0, err; if (nla == NULL) return -EINVAL; err = nla_parse_nested(tb, TCA_DEF_MAX, nla, simple_policy); if (err < 0) return err; if (tb[TCA_DEF_PARMS] == NULL) return -EINVAL; if (tb[TCA_DEF_DATA] == NULL) return -EINVAL; parm = nla_data(tb[TCA_DEF_PARMS]); defdata = nla_data(tb[TCA_DEF_DATA]); pc = tcf_hash_check(parm->index, a, bind, &simp_hash_info); if (!pc) { pc = tcf_hash_create(parm->index, est, a, sizeof(*d), bind, &simp_idx_gen, &simp_hash_info); if (unlikely(!pc)) return -ENOMEM; d = to_defact(pc); ret = alloc_defdata(d, defdata); if (ret < 0) { kfree(pc); return ret; } d->tcf_action = parm->action; ret = ACT_P_CREATED; } else { d = to_defact(pc); if (!ovr) { tcf_simp_release(d, bind); return -EEXIST; } reset_policy(d, defdata, parm); } if (ret == ACT_P_CREATED) tcf_hash_insert(pc, &simp_hash_info); return ret; } static inline int tcf_simp_cleanup(struct tc_action *a, int bind) { struct tcf_defact *d = a->priv; if (d) return tcf_simp_release(d, bind); return 0; } static inline int tcf_simp_dump(struct sk_buff *skb, struct tc_action *a, int bind, int ref) { unsigned char *b = skb_tail_pointer(skb); struct tcf_defact *d = a->priv; struct tc_defact opt; struct tcf_t t; opt.index = d->tcf_index; opt.refcnt = d->tcf_refcnt - ref; opt.bindcnt = d->tcf_bindcnt - bind; opt.action = d->tcf_action; NLA_PUT(skb, TCA_DEF_PARMS, sizeof(opt), &opt); NLA_PUT_STRING(skb, TCA_DEF_DATA, d->tcfd_defdata); t.install = jiffies_to_clock_t(jiffies - d->tcf_tm.install); t.lastuse = jiffies_to_clock_t(jiffies - d->tcf_tm.lastuse); t.expires = jiffies_to_clock_t(d->tcf_tm.expires); NLA_PUT(skb, TCA_DEF_TM, sizeof(t), &t); return skb->len; nla_put_failure: nlmsg_trim(skb, b); return -1; } static struct tc_action_ops act_simp_ops = { .kind = "simple", .hinfo = &simp_hash_info, .type = TCA_ACT_SIMP, .capab = TCA_CAP_NONE, .owner = THIS_MODULE, .act = tcf_simp, .dump = tcf_simp_dump, .cleanup = tcf_simp_cleanup, .init = tcf_simp_init, .walk = tcf_generic_walker, }; 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);