linux/net/sched/act_mirred.c
Paul Blakey 5712bf9c5c net/sched: act_mirred: Use passed lastuse argument
stats_update callback is called by NIC drivers doing hardware
offloading of the mirred action. Lastuse is passed as argument
to specify when the stats was actually last updated and is not
always the current time.

Fixes: 9798e6fe4f ('net: act_mirred: allow statistic updates from offloaded actions')
Signed-off-by: Paul Blakey <paulb@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-20 11:14:24 -04:00

346 lines
8.2 KiB
C

/*
* net/sched/act_mirred.c packet mirroring and redirect actions
*
* 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 (2002-4)
*
* TODO: Add ingress support (and socket redirect support)
*
*/
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/errno.h>
#include <linux/skbuff.h>
#include <linux/rtnetlink.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/gfp.h>
#include <net/net_namespace.h>
#include <net/netlink.h>
#include <net/pkt_sched.h>
#include <linux/tc_act/tc_mirred.h>
#include <net/tc_act/tc_mirred.h>
#include <linux/if_arp.h>
#define MIRRED_TAB_MASK 7
static LIST_HEAD(mirred_list);
static DEFINE_SPINLOCK(mirred_list_lock);
static void tcf_mirred_release(struct tc_action *a, int bind)
{
struct tcf_mirred *m = to_mirred(a);
struct net_device *dev;
/* We could be called either in a RCU callback or with RTNL lock held. */
spin_lock_bh(&mirred_list_lock);
list_del(&m->tcfm_list);
dev = rcu_dereference_protected(m->tcfm_dev, 1);
if (dev)
dev_put(dev);
spin_unlock_bh(&mirred_list_lock);
}
static const struct nla_policy mirred_policy[TCA_MIRRED_MAX + 1] = {
[TCA_MIRRED_PARMS] = { .len = sizeof(struct tc_mirred) },
};
static int mirred_net_id;
static struct tc_action_ops act_mirred_ops;
static int tcf_mirred_init(struct net *net, struct nlattr *nla,
struct nlattr *est, struct tc_action **a, int ovr,
int bind)
{
struct tc_action_net *tn = net_generic(net, mirred_net_id);
struct nlattr *tb[TCA_MIRRED_MAX + 1];
struct tc_mirred *parm;
struct tcf_mirred *m;
struct net_device *dev;
int ret, ok_push = 0;
bool exists = false;
if (nla == NULL)
return -EINVAL;
ret = nla_parse_nested(tb, TCA_MIRRED_MAX, nla, mirred_policy);
if (ret < 0)
return ret;
if (tb[TCA_MIRRED_PARMS] == NULL)
return -EINVAL;
parm = nla_data(tb[TCA_MIRRED_PARMS]);
exists = tcf_hash_check(tn, parm->index, a, bind);
if (exists && bind)
return 0;
switch (parm->eaction) {
case TCA_EGRESS_MIRROR:
case TCA_EGRESS_REDIR:
break;
default:
if (exists)
tcf_hash_release(*a, bind);
return -EINVAL;
}
if (parm->ifindex) {
dev = __dev_get_by_index(net, parm->ifindex);
if (dev == NULL) {
if (exists)
tcf_hash_release(*a, bind);
return -ENODEV;
}
switch (dev->type) {
case ARPHRD_TUNNEL:
case ARPHRD_TUNNEL6:
case ARPHRD_SIT:
case ARPHRD_IPGRE:
case ARPHRD_VOID:
case ARPHRD_NONE:
ok_push = 0;
break;
default:
ok_push = 1;
break;
}
} else {
dev = NULL;
}
if (!exists) {
if (dev == NULL)
return -EINVAL;
ret = tcf_hash_create(tn, parm->index, est, a,
&act_mirred_ops, bind, true);
if (ret)
return ret;
ret = ACT_P_CREATED;
} else {
tcf_hash_release(*a, bind);
if (!ovr)
return -EEXIST;
}
m = to_mirred(*a);
ASSERT_RTNL();
m->tcf_action = parm->action;
m->tcfm_eaction = parm->eaction;
if (dev != NULL) {
m->tcfm_ifindex = parm->ifindex;
if (ret != ACT_P_CREATED)
dev_put(rcu_dereference_protected(m->tcfm_dev, 1));
dev_hold(dev);
rcu_assign_pointer(m->tcfm_dev, dev);
m->tcfm_ok_push = ok_push;
}
if (ret == ACT_P_CREATED) {
spin_lock_bh(&mirred_list_lock);
list_add(&m->tcfm_list, &mirred_list);
spin_unlock_bh(&mirred_list_lock);
tcf_hash_insert(tn, *a);
}
return ret;
}
static int tcf_mirred(struct sk_buff *skb, const struct tc_action *a,
struct tcf_result *res)
{
struct tcf_mirred *m = to_mirred(a);
struct net_device *dev;
struct sk_buff *skb2;
int retval, err;
u32 at;
tcf_lastuse_update(&m->tcf_tm);
bstats_cpu_update(this_cpu_ptr(m->common.cpu_bstats), skb);
rcu_read_lock();
retval = READ_ONCE(m->tcf_action);
dev = rcu_dereference(m->tcfm_dev);
if (unlikely(!dev)) {
pr_notice_once("tc mirred: target device is gone\n");
goto out;
}
if (unlikely(!(dev->flags & IFF_UP))) {
net_notice_ratelimited("tc mirred to Houston: device %s is down\n",
dev->name);
goto out;
}
at = G_TC_AT(skb->tc_verd);
skb2 = skb_clone(skb, GFP_ATOMIC);
if (!skb2)
goto out;
if (!(at & AT_EGRESS)) {
if (m->tcfm_ok_push)
skb_push_rcsum(skb2, skb->mac_len);
}
/* mirror is always swallowed */
if (m->tcfm_eaction != TCA_EGRESS_MIRROR)
skb2->tc_verd = SET_TC_FROM(skb2->tc_verd, at);
skb2->skb_iif = skb->dev->ifindex;
skb2->dev = dev;
err = dev_queue_xmit(skb2);
if (err) {
out:
qstats_overlimit_inc(this_cpu_ptr(m->common.cpu_qstats));
if (m->tcfm_eaction != TCA_EGRESS_MIRROR)
retval = TC_ACT_SHOT;
}
rcu_read_unlock();
return retval;
}
static void tcf_stats_update(struct tc_action *a, u64 bytes, u32 packets,
u64 lastuse)
{
struct tcf_mirred *m = to_mirred(a);
struct tcf_t *tm = &m->tcf_tm;
_bstats_cpu_update(this_cpu_ptr(a->cpu_bstats), bytes, packets);
tm->lastuse = lastuse;
}
static int tcf_mirred_dump(struct sk_buff *skb, struct tc_action *a, int bind,
int ref)
{
unsigned char *b = skb_tail_pointer(skb);
struct tcf_mirred *m = to_mirred(a);
struct tc_mirred opt = {
.index = m->tcf_index,
.action = m->tcf_action,
.refcnt = m->tcf_refcnt - ref,
.bindcnt = m->tcf_bindcnt - bind,
.eaction = m->tcfm_eaction,
.ifindex = m->tcfm_ifindex,
};
struct tcf_t t;
if (nla_put(skb, TCA_MIRRED_PARMS, sizeof(opt), &opt))
goto nla_put_failure;
tcf_tm_dump(&t, &m->tcf_tm);
if (nla_put_64bit(skb, TCA_MIRRED_TM, sizeof(t), &t, TCA_MIRRED_PAD))
goto nla_put_failure;
return skb->len;
nla_put_failure:
nlmsg_trim(skb, b);
return -1;
}
static int tcf_mirred_walker(struct net *net, struct sk_buff *skb,
struct netlink_callback *cb, int type,
const struct tc_action_ops *ops)
{
struct tc_action_net *tn = net_generic(net, mirred_net_id);
return tcf_generic_walker(tn, skb, cb, type, ops);
}
static int tcf_mirred_search(struct net *net, struct tc_action **a, u32 index)
{
struct tc_action_net *tn = net_generic(net, mirred_net_id);
return tcf_hash_search(tn, a, index);
}
static int mirred_device_event(struct notifier_block *unused,
unsigned long event, void *ptr)
{
struct net_device *dev = netdev_notifier_info_to_dev(ptr);
struct tcf_mirred *m;
ASSERT_RTNL();
if (event == NETDEV_UNREGISTER) {
spin_lock_bh(&mirred_list_lock);
list_for_each_entry(m, &mirred_list, tcfm_list) {
if (rcu_access_pointer(m->tcfm_dev) == dev) {
dev_put(dev);
/* Note : no rcu grace period necessary, as
* net_device are already rcu protected.
*/
RCU_INIT_POINTER(m->tcfm_dev, NULL);
}
}
spin_unlock_bh(&mirred_list_lock);
}
return NOTIFY_DONE;
}
static struct notifier_block mirred_device_notifier = {
.notifier_call = mirred_device_event,
};
static struct tc_action_ops act_mirred_ops = {
.kind = "mirred",
.type = TCA_ACT_MIRRED,
.owner = THIS_MODULE,
.act = tcf_mirred,
.stats_update = tcf_stats_update,
.dump = tcf_mirred_dump,
.cleanup = tcf_mirred_release,
.init = tcf_mirred_init,
.walk = tcf_mirred_walker,
.lookup = tcf_mirred_search,
.size = sizeof(struct tcf_mirred),
};
static __net_init int mirred_init_net(struct net *net)
{
struct tc_action_net *tn = net_generic(net, mirred_net_id);
return tc_action_net_init(tn, &act_mirred_ops, MIRRED_TAB_MASK);
}
static void __net_exit mirred_exit_net(struct net *net)
{
struct tc_action_net *tn = net_generic(net, mirred_net_id);
tc_action_net_exit(tn);
}
static struct pernet_operations mirred_net_ops = {
.init = mirred_init_net,
.exit = mirred_exit_net,
.id = &mirred_net_id,
.size = sizeof(struct tc_action_net),
};
MODULE_AUTHOR("Jamal Hadi Salim(2002)");
MODULE_DESCRIPTION("Device Mirror/redirect actions");
MODULE_LICENSE("GPL");
static int __init mirred_init_module(void)
{
int err = register_netdevice_notifier(&mirred_device_notifier);
if (err)
return err;
pr_info("Mirror/redirect action on\n");
return tcf_register_action(&act_mirred_ops, &mirred_net_ops);
}
static void __exit mirred_cleanup_module(void)
{
tcf_unregister_action(&act_mirred_ops, &mirred_net_ops);
unregister_netdevice_notifier(&mirred_device_notifier);
}
module_init(mirred_init_module);
module_exit(mirred_cleanup_module);