1 files changed, 143 insertions, 29 deletions

diff --git a/net/mac802154/tx.c b/net/mac802154/tx.c
index 7e253455f9dd..4d13f18f6f2c 100644
--- a/net/mac802154/tx.c
+++ b/net/mac802154/tx.c
@@ -1,15 +1,7 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * Copyright 2007-2012 Siemens AG
  *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2
- * as published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
  * Written by:
  * Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
  * Sergey Lapin <slapin@ossfans.org>
@@ -20,7 +12,7 @@
 #include <linux/netdevice.h>
 #include <linux/if_arp.h>
 #include <linux/crc-ccitt.h>
-#include <asm/unaligned.h>
+#include <linux/unaligned.h>
 
 #include <net/rtnetlink.h>
 #include <net/ieee802154_netdev.h>
@@ -30,10 +22,10 @@
 #include "ieee802154_i.h"
 #include "driver-ops.h"
 
-void ieee802154_xmit_worker(struct work_struct *work)
+void ieee802154_xmit_sync_worker(struct work_struct *work)
 {
 	struct ieee802154_local *local =
-		container_of(work, struct ieee802154_local, tx_work);
+		container_of(work, struct ieee802154_local, sync_tx_work);
 	struct sk_buff *skb = local->tx_skb;
 	struct net_device *dev = skb->dev;
 	int res;
@@ -42,16 +34,18 @@ void ieee802154_xmit_worker(struct work_struct *work)
 	if (res)
 		goto err_tx;
 
-	ieee802154_xmit_complete(&local->hw, skb, false);
+	DEV_STATS_INC(dev, tx_packets);
+	DEV_STATS_ADD(dev, tx_bytes, skb->len);
 
-	dev->stats.tx_packets++;
-	dev->stats.tx_bytes += skb->len;
+	ieee802154_xmit_complete(&local->hw, skb, false);
 
 	return;
 
 err_tx:
 	/* Restart the netif queue on each sub_if_data object. */
-	ieee802154_wake_queue(&local->hw);
+	ieee802154_release_queue(local);
+	if (atomic_dec_and_test(&local->phy->ongoing_txs))
+		wake_up(&local->phy->sync_txq);
 	kfree_skb(skb);
 	netdev_dbg(dev, "transmission failed\n");
 }
@@ -63,36 +57,156 @@ ieee802154_tx(struct ieee802154_local *local, struct sk_buff *skb)
 	int ret;
 
 	if (!(local->hw.flags & IEEE802154_HW_TX_OMIT_CKSUM)) {
-		u16 crc = crc_ccitt(0, skb->data, skb->len);
+		struct sk_buff *nskb;
+		u16 crc;
+
+		if (unlikely(skb_tailroom(skb) < IEEE802154_FCS_LEN)) {
+			nskb = skb_copy_expand(skb, 0, IEEE802154_FCS_LEN,
+					       GFP_ATOMIC);
+			if (likely(nskb)) {
+				consume_skb(skb);
+				skb = nskb;
+			} else {
+				goto err_free_skb;
+			}
+		}
 
+		crc = crc_ccitt(0, skb->data, skb->len);
 		put_unaligned_le16(crc, skb_put(skb, 2));
 	}
 
 	/* Stop the netif queue on each sub_if_data object. */
-	ieee802154_stop_queue(&local->hw);
+	ieee802154_hold_queue(local);
+	atomic_inc(&local->phy->ongoing_txs);
 
-	/* async is priority, otherwise sync is fallback */
+	/* Drivers should preferably implement the async callback. In some rare
+	 * cases they only provide a sync callback which we will use as a
+	 * fallback.
+	 */
 	if (local->ops->xmit_async) {
+		unsigned int len = skb->len;
+
 		ret = drv_xmit_async(local, skb);
-		if (ret) {
-			ieee802154_wake_queue(&local->hw);
-			goto err_tx;
-		}
+		if (ret)
+			goto err_wake_netif_queue;
 
-		dev->stats.tx_packets++;
-		dev->stats.tx_bytes += skb->len;
+		DEV_STATS_INC(dev, tx_packets);
+		DEV_STATS_ADD(dev, tx_bytes, len);
 	} else {
 		local->tx_skb = skb;
-		queue_work(local->workqueue, &local->tx_work);
+		queue_work(local->workqueue, &local->sync_tx_work);
 	}
 
 	return NETDEV_TX_OK;
 
-err_tx:
+err_wake_netif_queue:
+	ieee802154_release_queue(local);
+	if (atomic_dec_and_test(&local->phy->ongoing_txs))
+		wake_up(&local->phy->sync_txq);
+err_free_skb:
 	kfree_skb(skb);
 	return NETDEV_TX_OK;
 }
 
+static int ieee802154_sync_queue(struct ieee802154_local *local)
+{
+	int ret;
+
+	ieee802154_hold_queue(local);
+	ieee802154_disable_queue(local);
+	wait_event(local->phy->sync_txq, !atomic_read(&local->phy->ongoing_txs));
+	ret = local->tx_result;
+	ieee802154_release_queue(local);
+
+	return ret;
+}
+
+int ieee802154_sync_and_hold_queue(struct ieee802154_local *local)
+{
+	int ret;
+
+	ieee802154_hold_queue(local);
+	ret = ieee802154_sync_queue(local);
+	set_bit(WPAN_PHY_FLAG_STATE_QUEUE_STOPPED, &local->phy->flags);
+
+	return ret;
+}
+
+int ieee802154_mlme_op_pre(struct ieee802154_local *local)
+{
+	return ieee802154_sync_and_hold_queue(local);
+}
+
+int ieee802154_mlme_tx_locked(struct ieee802154_local *local,
+			      struct ieee802154_sub_if_data *sdata,
+			      struct sk_buff *skb)
+{
+	/* Avoid possible calls to ->ndo_stop() when we asynchronously perform
+	 * MLME transmissions.
+	 */
+	ASSERT_RTNL();
+
+	/* Ensure the device was not stopped, otherwise error out */
+	if (!local->open_count)
+		return -ENETDOWN;
+
+	/* Warn if the ieee802154 core thinks MLME frames can be sent while the
+	 * net interface expects this cannot happen.
+	 */
+	if (WARN_ON_ONCE(!netif_running(sdata->dev)))
+		return -ENETDOWN;
+
+	ieee802154_tx(local, skb);
+	return ieee802154_sync_queue(local);
+}
+
+int ieee802154_mlme_tx(struct ieee802154_local *local,
+		       struct ieee802154_sub_if_data *sdata,
+		       struct sk_buff *skb)
+{
+	int ret;
+
+	rtnl_lock();
+	ret = ieee802154_mlme_tx_locked(local, sdata, skb);
+	rtnl_unlock();
+
+	return ret;
+}
+
+void ieee802154_mlme_op_post(struct ieee802154_local *local)
+{
+	ieee802154_release_queue(local);
+}
+
+int ieee802154_mlme_tx_one_locked(struct ieee802154_local *local,
+				  struct ieee802154_sub_if_data *sdata,
+				  struct sk_buff *skb)
+{
+	int ret;
+
+	ieee802154_mlme_op_pre(local);
+	ret = ieee802154_mlme_tx_locked(local, sdata, skb);
+	ieee802154_mlme_op_post(local);
+
+	return ret;
+}
+
+static bool ieee802154_queue_is_stopped(struct ieee802154_local *local)
+{
+	return test_bit(WPAN_PHY_FLAG_STATE_QUEUE_STOPPED, &local->phy->flags);
+}
+
+static netdev_tx_t
+ieee802154_hot_tx(struct ieee802154_local *local, struct sk_buff *skb)
+{
+	/* Warn if the net interface tries to transmit frames while the
+	 * ieee802154 core assumes the queue is stopped.
+	 */
+	WARN_ON_ONCE(ieee802154_queue_is_stopped(local));
+
+	return ieee802154_tx(local, skb);
+}
+
 netdev_tx_t
 ieee802154_monitor_start_xmit(struct sk_buff *skb, struct net_device *dev)
 {
@@ -100,7 +214,7 @@ ieee802154_monitor_start_xmit(struct sk_buff *skb, struct net_device *dev)
 
 	skb->skb_iif = dev->ifindex;
 
-	return ieee802154_tx(sdata->local, skb);
+	return ieee802154_hot_tx(sdata->local, skb);
 }
 
 netdev_tx_t
@@ -122,5 +236,5 @@ ieee802154_subif_start_xmit(struct sk_buff *skb, struct net_device *dev)
 
 	skb->skb_iif = dev->ifindex;
 
-	return ieee802154_tx(sdata->local, skb);
+	return ieee802154_hot_tx(sdata->local, skb);
 }