kernel-fxtec-pro1x/net/mac802154/main.c
Koen Zandberg aef00c15b8 mac802154: Fixes kernel oops when unloading a radio driver
Destroying the workqueue before unregistering the net device caused a
kernel oops

Signed-off-by: Koen Zandberg <koen@bergzand.net>
Acked-by: Alexander Aring <aar@pengutronix.de>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2016-02-23 20:29:40 +01:00

249 lines
6 KiB
C

/*
* Copyright (C) 2007-2012 Siemens AG
*
* Written by:
* Alexander Smirnov <alex.bluesman.smirnov@gmail.com>
*
* 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.
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/netdevice.h>
#include <net/netlink.h>
#include <net/nl802154.h>
#include <net/mac802154.h>
#include <net/ieee802154_netdev.h>
#include <net/route.h>
#include <net/cfg802154.h>
#include "ieee802154_i.h"
#include "cfg.h"
static void ieee802154_tasklet_handler(unsigned long data)
{
struct ieee802154_local *local = (struct ieee802154_local *)data;
struct sk_buff *skb;
while ((skb = skb_dequeue(&local->skb_queue))) {
switch (skb->pkt_type) {
case IEEE802154_RX_MSG:
/* Clear skb->pkt_type in order to not confuse kernel
* netstack.
*/
skb->pkt_type = 0;
ieee802154_rx(local, skb);
break;
default:
WARN(1, "mac802154: Packet is of unknown type %d\n",
skb->pkt_type);
kfree_skb(skb);
break;
}
}
}
struct ieee802154_hw *
ieee802154_alloc_hw(size_t priv_data_len, const struct ieee802154_ops *ops)
{
struct wpan_phy *phy;
struct ieee802154_local *local;
size_t priv_size;
if (WARN_ON(!ops || !(ops->xmit_async || ops->xmit_sync) || !ops->ed ||
!ops->start || !ops->stop || !ops->set_channel))
return NULL;
/* Ensure 32-byte alignment of our private data and hw private data.
* We use the wpan_phy priv data for both our ieee802154_local and for
* the driver's private data
*
* in memory it'll be like this:
*
* +-------------------------+
* | struct wpan_phy |
* +-------------------------+
* | struct ieee802154_local |
* +-------------------------+
* | driver's private data |
* +-------------------------+
*
* Due to ieee802154 layer isn't aware of driver and MAC structures,
* so lets align them here.
*/
priv_size = ALIGN(sizeof(*local), NETDEV_ALIGN) + priv_data_len;
phy = wpan_phy_new(&mac802154_config_ops, priv_size);
if (!phy) {
pr_err("failure to allocate master IEEE802.15.4 device\n");
return NULL;
}
phy->privid = mac802154_wpan_phy_privid;
local = wpan_phy_priv(phy);
local->phy = phy;
local->hw.phy = local->phy;
local->hw.priv = (char *)local + ALIGN(sizeof(*local), NETDEV_ALIGN);
local->ops = ops;
INIT_LIST_HEAD(&local->interfaces);
mutex_init(&local->iflist_mtx);
tasklet_init(&local->tasklet,
ieee802154_tasklet_handler,
(unsigned long)local);
skb_queue_head_init(&local->skb_queue);
INIT_WORK(&local->tx_work, ieee802154_xmit_worker);
/* init supported flags with 802.15.4 default ranges */
phy->supported.max_minbe = 8;
phy->supported.min_maxbe = 3;
phy->supported.max_maxbe = 8;
phy->supported.min_frame_retries = 0;
phy->supported.max_frame_retries = 7;
phy->supported.max_csma_backoffs = 5;
phy->supported.lbt = NL802154_SUPPORTED_BOOL_FALSE;
/* always supported */
phy->supported.iftypes = BIT(NL802154_IFTYPE_NODE);
return &local->hw;
}
EXPORT_SYMBOL(ieee802154_alloc_hw);
void ieee802154_free_hw(struct ieee802154_hw *hw)
{
struct ieee802154_local *local = hw_to_local(hw);
BUG_ON(!list_empty(&local->interfaces));
mutex_destroy(&local->iflist_mtx);
wpan_phy_free(local->phy);
}
EXPORT_SYMBOL(ieee802154_free_hw);
static void ieee802154_setup_wpan_phy_pib(struct wpan_phy *wpan_phy)
{
/* TODO warn on empty symbol_duration
* Should be done when all drivers sets this value.
*/
wpan_phy->lifs_period = IEEE802154_LIFS_PERIOD *
wpan_phy->symbol_duration;
wpan_phy->sifs_period = IEEE802154_SIFS_PERIOD *
wpan_phy->symbol_duration;
}
int ieee802154_register_hw(struct ieee802154_hw *hw)
{
struct ieee802154_local *local = hw_to_local(hw);
struct net_device *dev;
int rc = -ENOSYS;
local->workqueue =
create_singlethread_workqueue(wpan_phy_name(local->phy));
if (!local->workqueue) {
rc = -ENOMEM;
goto out;
}
hrtimer_init(&local->ifs_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
local->ifs_timer.function = ieee802154_xmit_ifs_timer;
wpan_phy_set_dev(local->phy, local->hw.parent);
ieee802154_setup_wpan_phy_pib(local->phy);
if (!(hw->flags & IEEE802154_HW_CSMA_PARAMS)) {
local->phy->supported.min_csma_backoffs = 4;
local->phy->supported.max_csma_backoffs = 4;
local->phy->supported.min_maxbe = 5;
local->phy->supported.max_maxbe = 5;
local->phy->supported.min_minbe = 3;
local->phy->supported.max_minbe = 3;
}
if (!(hw->flags & IEEE802154_HW_FRAME_RETRIES)) {
local->phy->supported.min_frame_retries = 3;
local->phy->supported.max_frame_retries = 3;
}
if (hw->flags & IEEE802154_HW_PROMISCUOUS)
local->phy->supported.iftypes |= BIT(NL802154_IFTYPE_MONITOR);
rc = wpan_phy_register(local->phy);
if (rc < 0)
goto out_wq;
rtnl_lock();
dev = ieee802154_if_add(local, "wpan%d", NET_NAME_ENUM,
NL802154_IFTYPE_NODE,
cpu_to_le64(0x0000000000000000ULL));
if (IS_ERR(dev)) {
rtnl_unlock();
rc = PTR_ERR(dev);
goto out_phy;
}
rtnl_unlock();
return 0;
out_phy:
wpan_phy_unregister(local->phy);
out_wq:
destroy_workqueue(local->workqueue);
out:
return rc;
}
EXPORT_SYMBOL(ieee802154_register_hw);
void ieee802154_unregister_hw(struct ieee802154_hw *hw)
{
struct ieee802154_local *local = hw_to_local(hw);
tasklet_kill(&local->tasklet);
flush_workqueue(local->workqueue);
rtnl_lock();
ieee802154_remove_interfaces(local);
rtnl_unlock();
destroy_workqueue(local->workqueue);
wpan_phy_unregister(local->phy);
}
EXPORT_SYMBOL(ieee802154_unregister_hw);
static int __init ieee802154_init(void)
{
return ieee802154_iface_init();
}
static void __exit ieee802154_exit(void)
{
ieee802154_iface_exit();
rcu_barrier();
}
subsys_initcall(ieee802154_init);
module_exit(ieee802154_exit);
MODULE_DESCRIPTION("IEEE 802.15.4 subsystem");
MODULE_LICENSE("GPL v2");