Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 7ed0132f authored by Rémi Denis-Courmont's avatar Rémi Denis-Courmont Committed by David S. Miller
Browse files

Phonet: put protocols array under RCU 



Signed-off-by: default avatarRémi Denis-Courmont <remi.denis-courmont@nokia.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 998221c2

net/phonet/af_phonet.c

+11 −9
Original line number Diff line number Diff line
@@ -35,7 +35,6 @@ 


/* Transport protocol registration */

static struct phonet_protocol *proto_tab[PHONET_NPROTO] __read_mostly;

static DEFINE_SPINLOCK(proto_tab_lock);



static struct phonet_protocol *phonet_proto_get(int protocol)

{
@@ -44,11 +43,11 @@ static struct phonet_protocol *phonet_proto_get(int protocol) 
	if (protocol >= PHONET_NPROTO)

		return NULL;



	spin_lock(&proto_tab_lock);

	rcu_read_lock();

	pp = proto_tab[protocol];

	if (pp && !try_module_get(pp->prot->owner))

		pp = NULL;

	spin_unlock(&proto_tab_lock);

	rcu_read_unlock();



	return pp;

}
@@ -439,6 +438,8 @@ static struct packet_type phonet_packet_type __read_mostly = { 
	.func = phonet_rcv,

};



static DEFINE_MUTEX(proto_tab_lock);



int __init_or_module phonet_proto_register(int protocol,

						struct phonet_protocol *pp)

{
@@ -451,12 +452,12 @@ int __init_or_module phonet_proto_register(int protocol, 
	if (err)

		return err;



	spin_lock(&proto_tab_lock);

	mutex_lock(&proto_tab_lock);

	if (proto_tab[protocol])

		err = -EBUSY;

	else

		proto_tab[protocol] = pp;

	spin_unlock(&proto_tab_lock);

		rcu_assign_pointer(proto_tab[protocol], pp);

	mutex_unlock(&proto_tab_lock);



	return err;

}
@@ -464,10 +465,11 @@ EXPORT_SYMBOL(phonet_proto_register); 


void phonet_proto_unregister(int protocol, struct phonet_protocol *pp)

{

	spin_lock(&proto_tab_lock);

	mutex_lock(&proto_tab_lock);

	BUG_ON(proto_tab[protocol] != pp);

	proto_tab[protocol] = NULL;

	spin_unlock(&proto_tab_lock);

	rcu_assign_pointer(proto_tab[protocol], NULL);

	mutex_unlock(&proto_tab_lock);

	synchronize_rcu();

	proto_unregister(pp->prot);

}

EXPORT_SYMBOL(phonet_proto_unregister);