From 7313bb8f3dd6e28bcf9c42adfd54a5cf9a4949e0 Mon Sep 17 00:00:00 2001
From: Karl Hiramoto <karl@hiramoto.org>
Date: Thu, 8 Jul 2010 20:55:30 +0000
Subject: atm: propagate signal changes via notifier
Add notifier chain for changes in atm_dev.
Clients like br2684 will call register_atmdevice_notifier() to be notified of
changes. Drivers will call atm_dev_signal_change() to notify clients like
br2684 of the change.
On DSL and ATM devices it's usefull to have a know if you have a carrier
signal. netdevice LOWER_UP changes can be propagated to userspace via netlink
monitor.
Signed-off-by: Karl Hiramoto <karl@hiramoto.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
net/atm/common.c | 30 ++++++++++++++++++++++++++++++
1 file changed, 30 insertions(+)
(limited to 'net/atm')
diff --git a/net/atm/common.c b/net/atm/common.c
index b43feb1a3995..940404a73b3d 100644
--- a/net/atm/common.c
+++ b/net/atm/common.c
@@ -37,6 +37,8 @@ EXPORT_SYMBOL(vcc_hash);
DEFINE_RWLOCK(vcc_sklist_lock);
EXPORT_SYMBOL(vcc_sklist_lock);
+static ATOMIC_NOTIFIER_HEAD(atm_dev_notify_chain);
+
static void __vcc_insert_socket(struct sock *sk)
{
struct atm_vcc *vcc = atm_sk(sk);
@@ -212,6 +214,22 @@ void vcc_release_async(struct atm_vcc *vcc, int reply)
}
EXPORT_SYMBOL(vcc_release_async);
+void atm_dev_signal_change(struct atm_dev *dev, char signal)
+{
+ pr_debug("%s signal=%d dev=%p number=%d dev->signal=%d\n",
+ __func__, signal, dev, dev->number, dev->signal);
+
+ /* atm driver sending invalid signal */
+ WARN_ON(signal < ATM_PHY_SIG_LOST || signal > ATM_PHY_SIG_FOUND);
+
+ if (dev->signal == signal)
+ return; /* no change */
+
+ dev->signal = signal;
+
+ atomic_notifier_call_chain(&atm_dev_notify_chain, signal, dev);
+}
+EXPORT_SYMBOL(atm_dev_signal_change);
void atm_dev_release_vccs(struct atm_dev *dev)
{
@@ -781,6 +799,18 @@ int vcc_getsockopt(struct socket *sock, int level, int optname,
return vcc->dev->ops->getsockopt(vcc, level, optname, optval, len);
}
+int register_atmdevice_notifier(struct notifier_block *nb)
+{
+ return atomic_notifier_chain_register(&atm_dev_notify_chain, nb);
+}
+EXPORT_SYMBOL_GPL(register_atmdevice_notifier);
+
+void unregister_atmdevice_notifier(struct notifier_block *nb)
+{
+ atomic_notifier_chain_unregister(&atm_dev_notify_chain, nb);
+}
+EXPORT_SYMBOL_GPL(unregister_atmdevice_notifier);
+
static int __init atm_init(void)
{
int error;
--
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