1 files changed, 27 insertions, 29 deletions

diff --git a/net/mac802154/tx.c b/net/mac802154/tx.c
index 2eb06c2cf96d..513e760a8557 100644
--- a/net/mac802154/tx.c
+++ b/net/mac802154/tx.c
@@ -30,7 +30,7 @@
 /* IEEE 802.15.4 transceivers can sleep during the xmit session, so process
  * packets through the workqueue.
  */
-struct xmit_work {
+struct wpan_xmit_cb {
 	struct sk_buff *skb;
 	struct work_struct work;
 	struct ieee802154_local *local;
@@ -38,50 +38,54 @@ struct xmit_work {
 	u8 page;
 };
 
+static inline struct wpan_xmit_cb *wpan_xmit_cb(const struct sk_buff *skb)
+{
+	BUILD_BUG_ON(sizeof(skb->cb) < sizeof(struct wpan_xmit_cb));
+
+	return (struct wpan_xmit_cb *)skb->cb;
+}
+
 static void mac802154_xmit_worker(struct work_struct *work)
 {
-	struct xmit_work *xw = container_of(work, struct xmit_work, work);
+	struct wpan_xmit_cb *cb = container_of(work, struct wpan_xmit_cb, work);
 	struct ieee802154_sub_if_data *sdata;
 	int res;
 
-	mutex_lock(&xw->local->phy->pib_lock);
-	if (xw->local->phy->current_channel != xw->chan ||
-	    xw->local->phy->current_page != xw->page) {
-		res = xw->local->ops->set_channel(&xw->local->hw,
-						  xw->page,
-						  xw->chan);
+	mutex_lock(&cb->local->phy->pib_lock);
+	if (cb->local->phy->current_channel != cb->chan ||
+	    cb->local->phy->current_page != cb->page) {
+		res = cb->local->ops->set_channel(&cb->local->hw, cb->page,
+						  cb->chan);
 		if (res) {
 			pr_debug("set_channel failed\n");
 			goto out;
 		}
 
-		xw->local->phy->current_channel = xw->chan;
-		xw->local->phy->current_page = xw->page;
+		cb->local->phy->current_channel = cb->chan;
+		cb->local->phy->current_page = cb->page;
 	}
 
-	res = xw->local->ops->xmit(&xw->local->hw, xw->skb);
+	res = cb->local->ops->xmit(&cb->local->hw, cb->skb);
 	if (res)
 		pr_debug("transmission failed\n");
 
 out:
-	mutex_unlock(&xw->local->phy->pib_lock);
+	mutex_unlock(&cb->local->phy->pib_lock);
 
 	/* Restart the netif queue on each sub_if_data object. */
 	rcu_read_lock();
-	list_for_each_entry_rcu(sdata, &xw->local->interfaces, list)
+	list_for_each_entry_rcu(sdata, &cb->local->interfaces, list)
 		netif_wake_queue(sdata->dev);
 	rcu_read_unlock();
 
-	dev_kfree_skb(xw->skb);
-
-	kfree(xw);
+	dev_kfree_skb(cb->skb);
 }
 
 static netdev_tx_t mac802154_tx(struct ieee802154_local *local,
 				struct sk_buff *skb, u8 page, u8 chan)
 {
-	struct xmit_work *work;
 	struct ieee802154_sub_if_data *sdata;
+	struct wpan_xmit_cb *cb = wpan_xmit_cb(skb);
 
 	if (!(local->phy->channels_supported[page] & (1 << chan))) {
 		WARN_ON(1);
@@ -101,25 +105,19 @@ static netdev_tx_t mac802154_tx(struct ieee802154_local *local,
 	if (skb_cow_head(skb, local->hw.extra_tx_headroom))
 		goto err_tx;
 
-	work = kzalloc(sizeof(*work), GFP_ATOMIC);
-	if (!work) {
-		kfree_skb(skb);
-		return NETDEV_TX_BUSY;
-	}
-
 	/* Stop the netif queue on each sub_if_data object. */
 	rcu_read_lock();
 	list_for_each_entry_rcu(sdata, &local->interfaces, list)
 		netif_stop_queue(sdata->dev);
 	rcu_read_unlock();
 
-	INIT_WORK(&work->work, mac802154_xmit_worker);
-	work->skb = skb;
-	work->local = local;
-	work->page = page;
-	work->chan = chan;
+	INIT_WORK(&cb->work, mac802154_xmit_worker);
+	cb->skb = skb;
+	cb->local = local;
+	cb->page = page;
+	cb->chan = chan;
 
-	queue_work(local->workqueue, &work->work);
+	queue_work(local->workqueue, &cb->work);
 
 	return NETDEV_TX_OK;