linux/net/mac802154/tx.c
Alexander Aring c38383530f mac802154: tx: fix synced xmit deadlock
This patch reverts 6001d52 ("mac802154: tx: don't allow if down while
sync tx"). This has side effects with stop callback which flush the
transmit workqueue. The stop callback will wait until the workqueue is
flushed and holding the rtnl lock. That means it can happen that the stop
callback waits forever because it try to lock the rtnl mutex which is
already hold by stop callback.

Cc: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Alexander Aring <alex.aring@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2015-12-10 19:17:11 +01:00

127 lines
3.1 KiB
C

/*
* 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>
* Maxim Gorbachyov <maxim.gorbachev@siemens.com>
* Alexander Smirnov <alex.bluesman.smirnov@gmail.com>
*/
#include <linux/netdevice.h>
#include <linux/if_arp.h>
#include <linux/crc-ccitt.h>
#include <asm/unaligned.h>
#include <net/rtnetlink.h>
#include <net/ieee802154_netdev.h>
#include <net/mac802154.h>
#include <net/cfg802154.h>
#include "ieee802154_i.h"
#include "driver-ops.h"
void ieee802154_xmit_worker(struct work_struct *work)
{
struct ieee802154_local *local =
container_of(work, struct ieee802154_local, tx_work);
struct sk_buff *skb = local->tx_skb;
struct net_device *dev = skb->dev;
int res;
res = drv_xmit_sync(local, skb);
if (res)
goto err_tx;
ieee802154_xmit_complete(&local->hw, skb, false);
dev->stats.tx_packets++;
dev->stats.tx_bytes += skb->len;
return;
err_tx:
/* Restart the netif queue on each sub_if_data object. */
ieee802154_wake_queue(&local->hw);
kfree_skb(skb);
netdev_dbg(dev, "transmission failed\n");
}
static netdev_tx_t
ieee802154_tx(struct ieee802154_local *local, struct sk_buff *skb)
{
struct net_device *dev = skb->dev;
int ret;
if (!(local->hw.flags & IEEE802154_HW_TX_OMIT_CKSUM)) {
u16 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);
/* async is priority, otherwise sync is fallback */
if (local->ops->xmit_async) {
ret = drv_xmit_async(local, skb);
if (ret) {
ieee802154_wake_queue(&local->hw);
goto err_tx;
}
dev->stats.tx_packets++;
dev->stats.tx_bytes += skb->len;
} else {
local->tx_skb = skb;
queue_work(local->workqueue, &local->tx_work);
}
return NETDEV_TX_OK;
err_tx:
kfree_skb(skb);
return NETDEV_TX_OK;
}
netdev_tx_t
ieee802154_monitor_start_xmit(struct sk_buff *skb, struct net_device *dev)
{
struct ieee802154_sub_if_data *sdata = IEEE802154_DEV_TO_SUB_IF(dev);
skb->skb_iif = dev->ifindex;
return ieee802154_tx(sdata->local, skb);
}
netdev_tx_t
ieee802154_subif_start_xmit(struct sk_buff *skb, struct net_device *dev)
{
struct ieee802154_sub_if_data *sdata = IEEE802154_DEV_TO_SUB_IF(dev);
int rc;
/* TODO we should move it to wpan_dev_hard_header and dev_hard_header
* functions. The reason is wireshark will show a mac header which is
* with security fields but the payload is not encrypted.
*/
rc = mac802154_llsec_encrypt(&sdata->sec, skb);
if (rc) {
netdev_warn(dev, "encryption failed: %i\n", rc);
kfree_skb(skb);
return NETDEV_TX_OK;
}
skb->skb_iif = dev->ifindex;
return ieee802154_tx(sdata->local, skb);
}