mac802154: remove mib lock

This patch removes the mib lock. The new locking mechanism is to protect
the mib values with the rtnl lock. Note that this isn't always necessary
if we have an interface up the most mib values are readonly (e.g.
address settings). With this behaviour we can remove locking in
hotpath like frame parsing completely. It depends on context if we need
to hold the rtnl lock or not, this makes the callbacks of
ieee802154_mlme_ops unnecessary because these callbacks hols always the
locks.

Signed-off-by: Alexander Aring <alex.aring@gmail.com>
Reviewed-by: Stefan Schmidt <stefan@osg.samsung.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

5 files changed, 2 insertions, 73 deletions

diff --git a/net/mac802154/ieee802154_i.h b/net/mac802154/ieee802154_i.h
index 56b3847466e9..eec668f3637f 100644
--- a/net/mac802154/ieee802154_i.h
+++ b/net/mac802154/ieee802154_i.h
@@ -86,8 +86,6 @@ struct ieee802154_sub_if_data {
 	unsigned long state;
 	char name[IFNAMSIZ];
 
-	spinlock_t mib_lock;
-
 	/* protects sec from concurrent access by netlink. access by
 	 * encrypt/decrypt/header_create safe without additional protection.
 	 */
@@ -136,10 +134,6 @@ ieee802154_subif_start_xmit(struct sk_buff *skb, struct net_device *dev);
 enum hrtimer_restart ieee802154_xmit_ifs_timer(struct hrtimer *timer);
 
 /* MIB callbacks */
-void mac802154_dev_set_short_addr(struct net_device *dev, __le16 val);
-__le16 mac802154_dev_get_short_addr(const struct net_device *dev);
-__le16 mac802154_dev_get_pan_id(const struct net_device *dev);
-void mac802154_dev_set_pan_id(struct net_device *dev, __le16 val);
 void mac802154_dev_set_page_channel(struct net_device *dev, u8 page, u8 chan);
 
 int mac802154_get_params(struct net_device *dev,
diff --git a/net/mac802154/iface.c b/net/mac802154/iface.c
index 0ec7bc402e29..f30788d2702f 100644
--- a/net/mac802154/iface.c
+++ b/net/mac802154/iface.c
@@ -63,7 +63,6 @@ mac802154_wpan_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
 	int err = -ENOIOCTLCMD;
 
 	rtnl_lock();
-	spin_lock_bh(&sdata->mib_lock);
 
 	switch (cmd) {
 	case SIOCGIFADDR:
@@ -88,7 +87,6 @@ mac802154_wpan_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
 	}
 	case SIOCSIFADDR:
 		if (netif_running(dev)) {
-			spin_unlock_bh(&sdata->mib_lock);
 			rtnl_unlock();
 			return -EBUSY;
 		}
@@ -111,7 +109,6 @@ mac802154_wpan_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
 		break;
 	}
 
-	spin_unlock_bh(&sdata->mib_lock);
 	rtnl_unlock();
 	return err;
 }
@@ -374,8 +371,6 @@ static int mac802154_header_create(struct sk_buff *skb,
 		return -EINVAL;
 
 	if (!saddr) {
-		spin_lock_bh(&sdata->mib_lock);
-
 		if (wpan_dev->short_addr == cpu_to_le16(IEEE802154_ADDR_BROADCAST) ||
 		    wpan_dev->short_addr == cpu_to_le16(IEEE802154_ADDR_UNDEF) ||
 		    wpan_dev->pan_id == cpu_to_le16(IEEE802154_PANID_BROADCAST)) {
@@ -387,8 +382,6 @@ static int mac802154_header_create(struct sk_buff *skb,
 		}
 
 		hdr.source.pan_id = wpan_dev->pan_id;
-
-		spin_unlock_bh(&sdata->mib_lock);
 	} else {
 		hdr.source = *(const struct ieee802154_addr *)saddr;
 	}
@@ -500,7 +493,6 @@ ieee802154_setup_sdata(struct ieee802154_sub_if_data *sdata,
 		sdata->dev->ml_priv = &mac802154_mlme_wpan;
 		wpan_dev->promiscuous_mode = false;
 
-		spin_lock_init(&sdata->mib_lock);
 		mutex_init(&sdata->sec_mtx);
 
 		mac802154_llsec_init(&sdata->sec);
diff --git a/net/mac802154/mac_cmd.c b/net/mac802154/mac_cmd.c
index 3b347d4d3d4c..5220c2b2735b 100644
--- a/net/mac802154/mac_cmd.c
+++ b/net/mac802154/mac_cmd.c
@@ -43,8 +43,8 @@ static int mac802154_mlme_start_req(struct net_device *dev,
 
 	BUG_ON(addr->mode != IEEE802154_ADDR_SHORT);
 
-	mac802154_dev_set_pan_id(dev, addr->pan_id);
-	mac802154_dev_set_short_addr(dev, addr->short_addr);
+	dev->ieee802154_ptr->pan_id = addr->pan_id;
+	dev->ieee802154_ptr->short_addr = addr->short_addr;
 	mac802154_dev_set_page_channel(dev, page, channel);
 
 	if (ops->llsec) {
@@ -151,8 +151,6 @@ static struct ieee802154_llsec_ops mac802154_llsec_ops = {
 
 struct ieee802154_mlme_ops mac802154_mlme_wpan = {
 	.start_req = mac802154_mlme_start_req,
-	.get_pan_id = mac802154_dev_get_pan_id,
-	.get_short_addr = mac802154_dev_get_short_addr,
 
 	.llsec = &mac802154_llsec_ops,
 
diff --git a/net/mac802154/mib.c b/net/mac802154/mib.c
index 00a62de9cc23..73f94fbf8785 100644
--- a/net/mac802154/mib.c
+++ b/net/mac802154/mib.c
@@ -26,56 +26,6 @@
 #include "ieee802154_i.h"
 #include "driver-ops.h"
 
-void mac802154_dev_set_short_addr(struct net_device *dev, __le16 val)
-{
-	struct ieee802154_sub_if_data *sdata = IEEE802154_DEV_TO_SUB_IF(dev);
-
-	BUG_ON(dev->type != ARPHRD_IEEE802154);
-
-	spin_lock_bh(&sdata->mib_lock);
-	sdata->wpan_dev.short_addr = val;
-	spin_unlock_bh(&sdata->mib_lock);
-}
-
-__le16 mac802154_dev_get_short_addr(const struct net_device *dev)
-{
-	struct ieee802154_sub_if_data *sdata = IEEE802154_DEV_TO_SUB_IF(dev);
-	__le16 ret;
-
-	BUG_ON(dev->type != ARPHRD_IEEE802154);
-
-	spin_lock_bh(&sdata->mib_lock);
-	ret = sdata->wpan_dev.short_addr;
-	spin_unlock_bh(&sdata->mib_lock);
-
-	return ret;
-}
-
-__le16 mac802154_dev_get_pan_id(const struct net_device *dev)
-{
-	struct ieee802154_sub_if_data *sdata = IEEE802154_DEV_TO_SUB_IF(dev);
-	__le16 ret;
-
-	BUG_ON(dev->type != ARPHRD_IEEE802154);
-
-	spin_lock_bh(&sdata->mib_lock);
-	ret = sdata->wpan_dev.pan_id;
-	spin_unlock_bh(&sdata->mib_lock);
-
-	return ret;
-}
-
-void mac802154_dev_set_pan_id(struct net_device *dev, __le16 val)
-{
-	struct ieee802154_sub_if_data *sdata = IEEE802154_DEV_TO_SUB_IF(dev);
-
-	BUG_ON(dev->type != ARPHRD_IEEE802154);
-
-	spin_lock_bh(&sdata->mib_lock);
-	sdata->wpan_dev.pan_id = val;
-	spin_unlock_bh(&sdata->mib_lock);
-}
-
 void mac802154_dev_set_page_channel(struct net_device *dev, u8 page, u8 chan)
 {
 	struct ieee802154_sub_if_data *sdata = IEEE802154_DEV_TO_SUB_IF(dev);
diff --git a/net/mac802154/rx.c b/net/mac802154/rx.c
index c0d67b2b4132..e0f10063cac3 100644
--- a/net/mac802154/rx.c
+++ b/net/mac802154/rx.c
@@ -47,8 +47,6 @@ ieee802154_subif_frame(struct ieee802154_sub_if_data *sdata,
 
 	pr_debug("getting packet via slave interface %s\n", sdata->dev->name);
 
-	spin_lock_bh(&sdata->mib_lock);
-
 	span = wpan_dev->pan_id;
 	sshort = wpan_dev->short_addr;
 
@@ -83,13 +81,10 @@ ieee802154_subif_frame(struct ieee802154_sub_if_data *sdata,
 			skb->pkt_type = PACKET_OTHERHOST;
 		break;
 	default:
-		spin_unlock_bh(&sdata->mib_lock);
 		pr_debug("invalid dest mode\n");
 		goto fail;
 	}
 
-	spin_unlock_bh(&sdata->mib_lock);
-
 	skb->dev = sdata->dev;
 
 	rc = mac802154_llsec_decrypt(&sdata->sec, skb);