kernel-ark/net/rfkill/core.c
Julia Lawall bd2281b85d net/rfkill/core.c: Avoid leaving freed data in a list
The list_for_each_entry loop can fail, in which case the list element is
not removed from the list rfkill_fds.  Since this list is not accessed by
the loop, the addition of &data->list into the list is just moved after the
loop.

The sematic match that finds this problem is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@
expression E,E1,E2;
identifier l;
@@

*list_add(&E->l,E1);
... when != E1
    when != list_del(&E->l)
    when != list_del_init(&E->l)
    when != E = E2
*kfree(E);// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2011-05-16 14:10:42 -04:00

1280 lines
29 KiB
C

/*
* Copyright (C) 2006 - 2007 Ivo van Doorn
* Copyright (C) 2007 Dmitry Torokhov
* Copyright 2009 Johannes Berg <johannes@sipsolutions.net>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* 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.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the
* Free Software Foundation, Inc.,
* 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/workqueue.h>
#include <linux/capability.h>
#include <linux/list.h>
#include <linux/mutex.h>
#include <linux/rfkill.h>
#include <linux/sched.h>
#include <linux/spinlock.h>
#include <linux/miscdevice.h>
#include <linux/wait.h>
#include <linux/poll.h>
#include <linux/fs.h>
#include <linux/slab.h>
#include "rfkill.h"
#define POLL_INTERVAL (5 * HZ)
#define RFKILL_BLOCK_HW BIT(0)
#define RFKILL_BLOCK_SW BIT(1)
#define RFKILL_BLOCK_SW_PREV BIT(2)
#define RFKILL_BLOCK_ANY (RFKILL_BLOCK_HW |\
RFKILL_BLOCK_SW |\
RFKILL_BLOCK_SW_PREV)
#define RFKILL_BLOCK_SW_SETCALL BIT(31)
struct rfkill {
spinlock_t lock;
const char *name;
enum rfkill_type type;
unsigned long state;
u32 idx;
bool registered;
bool persistent;
const struct rfkill_ops *ops;
void *data;
#ifdef CONFIG_RFKILL_LEDS
struct led_trigger led_trigger;
const char *ledtrigname;
#endif
struct device dev;
struct list_head node;
struct delayed_work poll_work;
struct work_struct uevent_work;
struct work_struct sync_work;
};
#define to_rfkill(d) container_of(d, struct rfkill, dev)
struct rfkill_int_event {
struct list_head list;
struct rfkill_event ev;
};
struct rfkill_data {
struct list_head list;
struct list_head events;
struct mutex mtx;
wait_queue_head_t read_wait;
bool input_handler;
};
MODULE_AUTHOR("Ivo van Doorn <IvDoorn@gmail.com>");
MODULE_AUTHOR("Johannes Berg <johannes@sipsolutions.net>");
MODULE_DESCRIPTION("RF switch support");
MODULE_LICENSE("GPL");
/*
* The locking here should be made much smarter, we currently have
* a bit of a stupid situation because drivers might want to register
* the rfkill struct under their own lock, and take this lock during
* rfkill method calls -- which will cause an AB-BA deadlock situation.
*
* To fix that, we need to rework this code here to be mostly lock-free
* and only use the mutex for list manipulations, not to protect the
* various other global variables. Then we can avoid holding the mutex
* around driver operations, and all is happy.
*/
static LIST_HEAD(rfkill_list); /* list of registered rf switches */
static DEFINE_MUTEX(rfkill_global_mutex);
static LIST_HEAD(rfkill_fds); /* list of open fds of /dev/rfkill */
static unsigned int rfkill_default_state = 1;
module_param_named(default_state, rfkill_default_state, uint, 0444);
MODULE_PARM_DESC(default_state,
"Default initial state for all radio types, 0 = radio off");
static struct {
bool cur, sav;
} rfkill_global_states[NUM_RFKILL_TYPES];
static bool rfkill_epo_lock_active;
#ifdef CONFIG_RFKILL_LEDS
static void rfkill_led_trigger_event(struct rfkill *rfkill)
{
struct led_trigger *trigger;
if (!rfkill->registered)
return;
trigger = &rfkill->led_trigger;
if (rfkill->state & RFKILL_BLOCK_ANY)
led_trigger_event(trigger, LED_OFF);
else
led_trigger_event(trigger, LED_FULL);
}
static void rfkill_led_trigger_activate(struct led_classdev *led)
{
struct rfkill *rfkill;
rfkill = container_of(led->trigger, struct rfkill, led_trigger);
rfkill_led_trigger_event(rfkill);
}
static int rfkill_led_trigger_register(struct rfkill *rfkill)
{
rfkill->led_trigger.name = rfkill->ledtrigname
? : dev_name(&rfkill->dev);
rfkill->led_trigger.activate = rfkill_led_trigger_activate;
return led_trigger_register(&rfkill->led_trigger);
}
static void rfkill_led_trigger_unregister(struct rfkill *rfkill)
{
led_trigger_unregister(&rfkill->led_trigger);
}
#else
static void rfkill_led_trigger_event(struct rfkill *rfkill)
{
}
static inline int rfkill_led_trigger_register(struct rfkill *rfkill)
{
return 0;
}
static inline void rfkill_led_trigger_unregister(struct rfkill *rfkill)
{
}
#endif /* CONFIG_RFKILL_LEDS */
static void rfkill_fill_event(struct rfkill_event *ev, struct rfkill *rfkill,
enum rfkill_operation op)
{
unsigned long flags;
ev->idx = rfkill->idx;
ev->type = rfkill->type;
ev->op = op;
spin_lock_irqsave(&rfkill->lock, flags);
ev->hard = !!(rfkill->state & RFKILL_BLOCK_HW);
ev->soft = !!(rfkill->state & (RFKILL_BLOCK_SW |
RFKILL_BLOCK_SW_PREV));
spin_unlock_irqrestore(&rfkill->lock, flags);
}
static void rfkill_send_events(struct rfkill *rfkill, enum rfkill_operation op)
{
struct rfkill_data *data;
struct rfkill_int_event *ev;
list_for_each_entry(data, &rfkill_fds, list) {
ev = kzalloc(sizeof(*ev), GFP_KERNEL);
if (!ev)
continue;
rfkill_fill_event(&ev->ev, rfkill, op);
mutex_lock(&data->mtx);
list_add_tail(&ev->list, &data->events);
mutex_unlock(&data->mtx);
wake_up_interruptible(&data->read_wait);
}
}
static void rfkill_event(struct rfkill *rfkill)
{
if (!rfkill->registered)
return;
kobject_uevent(&rfkill->dev.kobj, KOBJ_CHANGE);
/* also send event to /dev/rfkill */
rfkill_send_events(rfkill, RFKILL_OP_CHANGE);
}
static bool __rfkill_set_hw_state(struct rfkill *rfkill,
bool blocked, bool *change)
{
unsigned long flags;
bool prev, any;
BUG_ON(!rfkill);
spin_lock_irqsave(&rfkill->lock, flags);
prev = !!(rfkill->state & RFKILL_BLOCK_HW);
if (blocked)
rfkill->state |= RFKILL_BLOCK_HW;
else
rfkill->state &= ~RFKILL_BLOCK_HW;
*change = prev != blocked;
any = rfkill->state & RFKILL_BLOCK_ANY;
spin_unlock_irqrestore(&rfkill->lock, flags);
rfkill_led_trigger_event(rfkill);
return any;
}
/**
* rfkill_set_block - wrapper for set_block method
*
* @rfkill: the rfkill struct to use
* @blocked: the new software state
*
* Calls the set_block method (when applicable) and handles notifications
* etc. as well.
*/
static void rfkill_set_block(struct rfkill *rfkill, bool blocked)
{
unsigned long flags;
int err;
if (unlikely(rfkill->dev.power.power_state.event & PM_EVENT_SLEEP))
return;
/*
* Some platforms (...!) generate input events which affect the
* _hard_ kill state -- whenever something tries to change the
* current software state query the hardware state too.
*/
if (rfkill->ops->query)
rfkill->ops->query(rfkill, rfkill->data);
spin_lock_irqsave(&rfkill->lock, flags);
if (rfkill->state & RFKILL_BLOCK_SW)
rfkill->state |= RFKILL_BLOCK_SW_PREV;
else
rfkill->state &= ~RFKILL_BLOCK_SW_PREV;
if (blocked)
rfkill->state |= RFKILL_BLOCK_SW;
else
rfkill->state &= ~RFKILL_BLOCK_SW;
rfkill->state |= RFKILL_BLOCK_SW_SETCALL;
spin_unlock_irqrestore(&rfkill->lock, flags);
err = rfkill->ops->set_block(rfkill->data, blocked);
spin_lock_irqsave(&rfkill->lock, flags);
if (err) {
/*
* Failed -- reset status to _prev, this may be different
* from what set set _PREV to earlier in this function
* if rfkill_set_sw_state was invoked.
*/
if (rfkill->state & RFKILL_BLOCK_SW_PREV)
rfkill->state |= RFKILL_BLOCK_SW;
else
rfkill->state &= ~RFKILL_BLOCK_SW;
}
rfkill->state &= ~RFKILL_BLOCK_SW_SETCALL;
rfkill->state &= ~RFKILL_BLOCK_SW_PREV;
spin_unlock_irqrestore(&rfkill->lock, flags);
rfkill_led_trigger_event(rfkill);
rfkill_event(rfkill);
}
#ifdef CONFIG_RFKILL_INPUT
static atomic_t rfkill_input_disabled = ATOMIC_INIT(0);
/**
* __rfkill_switch_all - Toggle state of all switches of given type
* @type: type of interfaces to be affected
* @state: the new state
*
* This function sets the state of all switches of given type,
* unless a specific switch is claimed by userspace (in which case,
* that switch is left alone) or suspended.
*
* Caller must have acquired rfkill_global_mutex.
*/
static void __rfkill_switch_all(const enum rfkill_type type, bool blocked)
{
struct rfkill *rfkill;
rfkill_global_states[type].cur = blocked;
list_for_each_entry(rfkill, &rfkill_list, node) {
if (rfkill->type != type)
continue;
rfkill_set_block(rfkill, blocked);
}
}
/**
* rfkill_switch_all - Toggle state of all switches of given type
* @type: type of interfaces to be affected
* @state: the new state
*
* Acquires rfkill_global_mutex and calls __rfkill_switch_all(@type, @state).
* Please refer to __rfkill_switch_all() for details.
*
* Does nothing if the EPO lock is active.
*/
void rfkill_switch_all(enum rfkill_type type, bool blocked)
{
if (atomic_read(&rfkill_input_disabled))
return;
mutex_lock(&rfkill_global_mutex);
if (!rfkill_epo_lock_active)
__rfkill_switch_all(type, blocked);
mutex_unlock(&rfkill_global_mutex);
}
/**
* rfkill_epo - emergency power off all transmitters
*
* This kicks all non-suspended rfkill devices to RFKILL_STATE_SOFT_BLOCKED,
* ignoring everything in its path but rfkill_global_mutex and rfkill->mutex.
*
* The global state before the EPO is saved and can be restored later
* using rfkill_restore_states().
*/
void rfkill_epo(void)
{
struct rfkill *rfkill;
int i;
if (atomic_read(&rfkill_input_disabled))
return;
mutex_lock(&rfkill_global_mutex);
rfkill_epo_lock_active = true;
list_for_each_entry(rfkill, &rfkill_list, node)
rfkill_set_block(rfkill, true);
for (i = 0; i < NUM_RFKILL_TYPES; i++) {
rfkill_global_states[i].sav = rfkill_global_states[i].cur;
rfkill_global_states[i].cur = true;
}
mutex_unlock(&rfkill_global_mutex);
}
/**
* rfkill_restore_states - restore global states
*
* Restore (and sync switches to) the global state from the
* states in rfkill_default_states. This can undo the effects of
* a call to rfkill_epo().
*/
void rfkill_restore_states(void)
{
int i;
if (atomic_read(&rfkill_input_disabled))
return;
mutex_lock(&rfkill_global_mutex);
rfkill_epo_lock_active = false;
for (i = 0; i < NUM_RFKILL_TYPES; i++)
__rfkill_switch_all(i, rfkill_global_states[i].sav);
mutex_unlock(&rfkill_global_mutex);
}
/**
* rfkill_remove_epo_lock - unlock state changes
*
* Used by rfkill-input manually unlock state changes, when
* the EPO switch is deactivated.
*/
void rfkill_remove_epo_lock(void)
{
if (atomic_read(&rfkill_input_disabled))
return;
mutex_lock(&rfkill_global_mutex);
rfkill_epo_lock_active = false;
mutex_unlock(&rfkill_global_mutex);
}
/**
* rfkill_is_epo_lock_active - returns true EPO is active
*
* Returns 0 (false) if there is NOT an active EPO contidion,
* and 1 (true) if there is an active EPO contition, which
* locks all radios in one of the BLOCKED states.
*
* Can be called in atomic context.
*/
bool rfkill_is_epo_lock_active(void)
{
return rfkill_epo_lock_active;
}
/**
* rfkill_get_global_sw_state - returns global state for a type
* @type: the type to get the global state of
*
* Returns the current global state for a given wireless
* device type.
*/
bool rfkill_get_global_sw_state(const enum rfkill_type type)
{
return rfkill_global_states[type].cur;
}
#endif
bool rfkill_set_hw_state(struct rfkill *rfkill, bool blocked)
{
bool ret, change;
ret = __rfkill_set_hw_state(rfkill, blocked, &change);
if (!rfkill->registered)
return ret;
if (change)
schedule_work(&rfkill->uevent_work);
return ret;
}
EXPORT_SYMBOL(rfkill_set_hw_state);
static void __rfkill_set_sw_state(struct rfkill *rfkill, bool blocked)
{
u32 bit = RFKILL_BLOCK_SW;
/* if in a ops->set_block right now, use other bit */
if (rfkill->state & RFKILL_BLOCK_SW_SETCALL)
bit = RFKILL_BLOCK_SW_PREV;
if (blocked)
rfkill->state |= bit;
else
rfkill->state &= ~bit;
}
bool rfkill_set_sw_state(struct rfkill *rfkill, bool blocked)
{
unsigned long flags;
bool prev, hwblock;
BUG_ON(!rfkill);
spin_lock_irqsave(&rfkill->lock, flags);
prev = !!(rfkill->state & RFKILL_BLOCK_SW);
__rfkill_set_sw_state(rfkill, blocked);
hwblock = !!(rfkill->state & RFKILL_BLOCK_HW);
blocked = blocked || hwblock;
spin_unlock_irqrestore(&rfkill->lock, flags);
if (!rfkill->registered)
return blocked;
if (prev != blocked && !hwblock)
schedule_work(&rfkill->uevent_work);
rfkill_led_trigger_event(rfkill);
return blocked;
}
EXPORT_SYMBOL(rfkill_set_sw_state);
void rfkill_init_sw_state(struct rfkill *rfkill, bool blocked)
{
unsigned long flags;
BUG_ON(!rfkill);
BUG_ON(rfkill->registered);
spin_lock_irqsave(&rfkill->lock, flags);
__rfkill_set_sw_state(rfkill, blocked);
rfkill->persistent = true;
spin_unlock_irqrestore(&rfkill->lock, flags);
}
EXPORT_SYMBOL(rfkill_init_sw_state);
void rfkill_set_states(struct rfkill *rfkill, bool sw, bool hw)
{
unsigned long flags;
bool swprev, hwprev;
BUG_ON(!rfkill);
spin_lock_irqsave(&rfkill->lock, flags);
/*
* No need to care about prev/setblock ... this is for uevent only
* and that will get triggered by rfkill_set_block anyway.
*/
swprev = !!(rfkill->state & RFKILL_BLOCK_SW);
hwprev = !!(rfkill->state & RFKILL_BLOCK_HW);
__rfkill_set_sw_state(rfkill, sw);
if (hw)
rfkill->state |= RFKILL_BLOCK_HW;
else
rfkill->state &= ~RFKILL_BLOCK_HW;
spin_unlock_irqrestore(&rfkill->lock, flags);
if (!rfkill->registered) {
rfkill->persistent = true;
} else {
if (swprev != sw || hwprev != hw)
schedule_work(&rfkill->uevent_work);
rfkill_led_trigger_event(rfkill);
}
}
EXPORT_SYMBOL(rfkill_set_states);
static ssize_t rfkill_name_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct rfkill *rfkill = to_rfkill(dev);
return sprintf(buf, "%s\n", rfkill->name);
}
static const char *rfkill_get_type_str(enum rfkill_type type)
{
BUILD_BUG_ON(NUM_RFKILL_TYPES != RFKILL_TYPE_FM + 1);
switch (type) {
case RFKILL_TYPE_WLAN:
return "wlan";
case RFKILL_TYPE_BLUETOOTH:
return "bluetooth";
case RFKILL_TYPE_UWB:
return "ultrawideband";
case RFKILL_TYPE_WIMAX:
return "wimax";
case RFKILL_TYPE_WWAN:
return "wwan";
case RFKILL_TYPE_GPS:
return "gps";
case RFKILL_TYPE_FM:
return "fm";
default:
BUG();
}
}
static ssize_t rfkill_type_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct rfkill *rfkill = to_rfkill(dev);
return sprintf(buf, "%s\n", rfkill_get_type_str(rfkill->type));
}
static ssize_t rfkill_idx_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct rfkill *rfkill = to_rfkill(dev);
return sprintf(buf, "%d\n", rfkill->idx);
}
static ssize_t rfkill_persistent_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct rfkill *rfkill = to_rfkill(dev);
return sprintf(buf, "%d\n", rfkill->persistent);
}
static ssize_t rfkill_hard_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct rfkill *rfkill = to_rfkill(dev);
return sprintf(buf, "%d\n", (rfkill->state & RFKILL_BLOCK_HW) ? 1 : 0 );
}
static ssize_t rfkill_soft_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct rfkill *rfkill = to_rfkill(dev);
return sprintf(buf, "%d\n", (rfkill->state & RFKILL_BLOCK_SW) ? 1 : 0 );
}
static ssize_t rfkill_soft_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
{
struct rfkill *rfkill = to_rfkill(dev);
unsigned long state;
int err;
if (!capable(CAP_NET_ADMIN))
return -EPERM;
err = strict_strtoul(buf, 0, &state);
if (err)
return err;
if (state > 1 )
return -EINVAL;
mutex_lock(&rfkill_global_mutex);
rfkill_set_block(rfkill, state);
mutex_unlock(&rfkill_global_mutex);
return err ?: count;
}
static u8 user_state_from_blocked(unsigned long state)
{
if (state & RFKILL_BLOCK_HW)
return RFKILL_USER_STATE_HARD_BLOCKED;
if (state & RFKILL_BLOCK_SW)
return RFKILL_USER_STATE_SOFT_BLOCKED;
return RFKILL_USER_STATE_UNBLOCKED;
}
static ssize_t rfkill_state_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct rfkill *rfkill = to_rfkill(dev);
return sprintf(buf, "%d\n", user_state_from_blocked(rfkill->state));
}
static ssize_t rfkill_state_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
{
struct rfkill *rfkill = to_rfkill(dev);
unsigned long state;
int err;
if (!capable(CAP_NET_ADMIN))
return -EPERM;
err = strict_strtoul(buf, 0, &state);
if (err)
return err;
if (state != RFKILL_USER_STATE_SOFT_BLOCKED &&
state != RFKILL_USER_STATE_UNBLOCKED)
return -EINVAL;
mutex_lock(&rfkill_global_mutex);
rfkill_set_block(rfkill, state == RFKILL_USER_STATE_SOFT_BLOCKED);
mutex_unlock(&rfkill_global_mutex);
return err ?: count;
}
static ssize_t rfkill_claim_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
return sprintf(buf, "%d\n", 0);
}
static ssize_t rfkill_claim_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
{
return -EOPNOTSUPP;
}
static struct device_attribute rfkill_dev_attrs[] = {
__ATTR(name, S_IRUGO, rfkill_name_show, NULL),
__ATTR(type, S_IRUGO, rfkill_type_show, NULL),
__ATTR(index, S_IRUGO, rfkill_idx_show, NULL),
__ATTR(persistent, S_IRUGO, rfkill_persistent_show, NULL),
__ATTR(state, S_IRUGO|S_IWUSR, rfkill_state_show, rfkill_state_store),
__ATTR(claim, S_IRUGO|S_IWUSR, rfkill_claim_show, rfkill_claim_store),
__ATTR(soft, S_IRUGO|S_IWUSR, rfkill_soft_show, rfkill_soft_store),
__ATTR(hard, S_IRUGO, rfkill_hard_show, NULL),
__ATTR_NULL
};
static void rfkill_release(struct device *dev)
{
struct rfkill *rfkill = to_rfkill(dev);
kfree(rfkill);
}
static int rfkill_dev_uevent(struct device *dev, struct kobj_uevent_env *env)
{
struct rfkill *rfkill = to_rfkill(dev);
unsigned long flags;
u32 state;
int error;
error = add_uevent_var(env, "RFKILL_NAME=%s", rfkill->name);
if (error)
return error;
error = add_uevent_var(env, "RFKILL_TYPE=%s",
rfkill_get_type_str(rfkill->type));
if (error)
return error;
spin_lock_irqsave(&rfkill->lock, flags);
state = rfkill->state;
spin_unlock_irqrestore(&rfkill->lock, flags);
error = add_uevent_var(env, "RFKILL_STATE=%d",
user_state_from_blocked(state));
return error;
}
void rfkill_pause_polling(struct rfkill *rfkill)
{
BUG_ON(!rfkill);
if (!rfkill->ops->poll)
return;
cancel_delayed_work_sync(&rfkill->poll_work);
}
EXPORT_SYMBOL(rfkill_pause_polling);
void rfkill_resume_polling(struct rfkill *rfkill)
{
BUG_ON(!rfkill);
if (!rfkill->ops->poll)
return;
schedule_work(&rfkill->poll_work.work);
}
EXPORT_SYMBOL(rfkill_resume_polling);
static int rfkill_suspend(struct device *dev, pm_message_t state)
{
struct rfkill *rfkill = to_rfkill(dev);
rfkill_pause_polling(rfkill);
return 0;
}
static int rfkill_resume(struct device *dev)
{
struct rfkill *rfkill = to_rfkill(dev);
bool cur;
if (!rfkill->persistent) {
cur = !!(rfkill->state & RFKILL_BLOCK_SW);
rfkill_set_block(rfkill, cur);
}
rfkill_resume_polling(rfkill);
return 0;
}
static struct class rfkill_class = {
.name = "rfkill",
.dev_release = rfkill_release,
.dev_attrs = rfkill_dev_attrs,
.dev_uevent = rfkill_dev_uevent,
.suspend = rfkill_suspend,
.resume = rfkill_resume,
};
bool rfkill_blocked(struct rfkill *rfkill)
{
unsigned long flags;
u32 state;
spin_lock_irqsave(&rfkill->lock, flags);
state = rfkill->state;
spin_unlock_irqrestore(&rfkill->lock, flags);
return !!(state & RFKILL_BLOCK_ANY);
}
EXPORT_SYMBOL(rfkill_blocked);
struct rfkill * __must_check rfkill_alloc(const char *name,
struct device *parent,
const enum rfkill_type type,
const struct rfkill_ops *ops,
void *ops_data)
{
struct rfkill *rfkill;
struct device *dev;
if (WARN_ON(!ops))
return NULL;
if (WARN_ON(!ops->set_block))
return NULL;
if (WARN_ON(!name))
return NULL;
if (WARN_ON(type == RFKILL_TYPE_ALL || type >= NUM_RFKILL_TYPES))
return NULL;
rfkill = kzalloc(sizeof(*rfkill), GFP_KERNEL);
if (!rfkill)
return NULL;
spin_lock_init(&rfkill->lock);
INIT_LIST_HEAD(&rfkill->node);
rfkill->type = type;
rfkill->name = name;
rfkill->ops = ops;
rfkill->data = ops_data;
dev = &rfkill->dev;
dev->class = &rfkill_class;
dev->parent = parent;
device_initialize(dev);
return rfkill;
}
EXPORT_SYMBOL(rfkill_alloc);
static void rfkill_poll(struct work_struct *work)
{
struct rfkill *rfkill;
rfkill = container_of(work, struct rfkill, poll_work.work);
/*
* Poll hardware state -- driver will use one of the
* rfkill_set{,_hw,_sw}_state functions and use its
* return value to update the current status.
*/
rfkill->ops->poll(rfkill, rfkill->data);
schedule_delayed_work(&rfkill->poll_work,
round_jiffies_relative(POLL_INTERVAL));
}
static void rfkill_uevent_work(struct work_struct *work)
{
struct rfkill *rfkill;
rfkill = container_of(work, struct rfkill, uevent_work);
mutex_lock(&rfkill_global_mutex);
rfkill_event(rfkill);
mutex_unlock(&rfkill_global_mutex);
}
static void rfkill_sync_work(struct work_struct *work)
{
struct rfkill *rfkill;
bool cur;
rfkill = container_of(work, struct rfkill, sync_work);
mutex_lock(&rfkill_global_mutex);
cur = rfkill_global_states[rfkill->type].cur;
rfkill_set_block(rfkill, cur);
mutex_unlock(&rfkill_global_mutex);
}
int __must_check rfkill_register(struct rfkill *rfkill)
{
static unsigned long rfkill_no;
struct device *dev = &rfkill->dev;
int error;
BUG_ON(!rfkill);
mutex_lock(&rfkill_global_mutex);
if (rfkill->registered) {
error = -EALREADY;
goto unlock;
}
rfkill->idx = rfkill_no;
dev_set_name(dev, "rfkill%lu", rfkill_no);
rfkill_no++;
list_add_tail(&rfkill->node, &rfkill_list);
error = device_add(dev);
if (error)
goto remove;
error = rfkill_led_trigger_register(rfkill);
if (error)
goto devdel;
rfkill->registered = true;
INIT_DELAYED_WORK(&rfkill->poll_work, rfkill_poll);
INIT_WORK(&rfkill->uevent_work, rfkill_uevent_work);
INIT_WORK(&rfkill->sync_work, rfkill_sync_work);
if (rfkill->ops->poll)
schedule_delayed_work(&rfkill->poll_work,
round_jiffies_relative(POLL_INTERVAL));
if (!rfkill->persistent || rfkill_epo_lock_active) {
schedule_work(&rfkill->sync_work);
} else {
#ifdef CONFIG_RFKILL_INPUT
bool soft_blocked = !!(rfkill->state & RFKILL_BLOCK_SW);
if (!atomic_read(&rfkill_input_disabled))
__rfkill_switch_all(rfkill->type, soft_blocked);
#endif
}
rfkill_send_events(rfkill, RFKILL_OP_ADD);
mutex_unlock(&rfkill_global_mutex);
return 0;
devdel:
device_del(&rfkill->dev);
remove:
list_del_init(&rfkill->node);
unlock:
mutex_unlock(&rfkill_global_mutex);
return error;
}
EXPORT_SYMBOL(rfkill_register);
void rfkill_unregister(struct rfkill *rfkill)
{
BUG_ON(!rfkill);
if (rfkill->ops->poll)
cancel_delayed_work_sync(&rfkill->poll_work);
cancel_work_sync(&rfkill->uevent_work);
cancel_work_sync(&rfkill->sync_work);
rfkill->registered = false;
device_del(&rfkill->dev);
mutex_lock(&rfkill_global_mutex);
rfkill_send_events(rfkill, RFKILL_OP_DEL);
list_del_init(&rfkill->node);
mutex_unlock(&rfkill_global_mutex);
rfkill_led_trigger_unregister(rfkill);
}
EXPORT_SYMBOL(rfkill_unregister);
void rfkill_destroy(struct rfkill *rfkill)
{
if (rfkill)
put_device(&rfkill->dev);
}
EXPORT_SYMBOL(rfkill_destroy);
static int rfkill_fop_open(struct inode *inode, struct file *file)
{
struct rfkill_data *data;
struct rfkill *rfkill;
struct rfkill_int_event *ev, *tmp;
data = kzalloc(sizeof(*data), GFP_KERNEL);
if (!data)
return -ENOMEM;
INIT_LIST_HEAD(&data->events);
mutex_init(&data->mtx);
init_waitqueue_head(&data->read_wait);
mutex_lock(&rfkill_global_mutex);
mutex_lock(&data->mtx);
/*
* start getting events from elsewhere but hold mtx to get
* startup events added first
*/
list_for_each_entry(rfkill, &rfkill_list, node) {
ev = kzalloc(sizeof(*ev), GFP_KERNEL);
if (!ev)
goto free;
rfkill_fill_event(&ev->ev, rfkill, RFKILL_OP_ADD);
list_add_tail(&ev->list, &data->events);
}
list_add(&data->list, &rfkill_fds);
mutex_unlock(&data->mtx);
mutex_unlock(&rfkill_global_mutex);
file->private_data = data;
return nonseekable_open(inode, file);
free:
mutex_unlock(&data->mtx);
mutex_unlock(&rfkill_global_mutex);
mutex_destroy(&data->mtx);
list_for_each_entry_safe(ev, tmp, &data->events, list)
kfree(ev);
kfree(data);
return -ENOMEM;
}
static unsigned int rfkill_fop_poll(struct file *file, poll_table *wait)
{
struct rfkill_data *data = file->private_data;
unsigned int res = POLLOUT | POLLWRNORM;
poll_wait(file, &data->read_wait, wait);
mutex_lock(&data->mtx);
if (!list_empty(&data->events))
res = POLLIN | POLLRDNORM;
mutex_unlock(&data->mtx);
return res;
}
static bool rfkill_readable(struct rfkill_data *data)
{
bool r;
mutex_lock(&data->mtx);
r = !list_empty(&data->events);
mutex_unlock(&data->mtx);
return r;
}
static ssize_t rfkill_fop_read(struct file *file, char __user *buf,
size_t count, loff_t *pos)
{
struct rfkill_data *data = file->private_data;
struct rfkill_int_event *ev;
unsigned long sz;
int ret;
mutex_lock(&data->mtx);
while (list_empty(&data->events)) {
if (file->f_flags & O_NONBLOCK) {
ret = -EAGAIN;
goto out;
}
mutex_unlock(&data->mtx);
ret = wait_event_interruptible(data->read_wait,
rfkill_readable(data));
mutex_lock(&data->mtx);
if (ret)
goto out;
}
ev = list_first_entry(&data->events, struct rfkill_int_event,
list);
sz = min_t(unsigned long, sizeof(ev->ev), count);
ret = sz;
if (copy_to_user(buf, &ev->ev, sz))
ret = -EFAULT;
list_del(&ev->list);
kfree(ev);
out:
mutex_unlock(&data->mtx);
return ret;
}
static ssize_t rfkill_fop_write(struct file *file, const char __user *buf,
size_t count, loff_t *pos)
{
struct rfkill *rfkill;
struct rfkill_event ev;
/* we don't need the 'hard' variable but accept it */
if (count < RFKILL_EVENT_SIZE_V1 - 1)
return -EINVAL;
/*
* Copy as much data as we can accept into our 'ev' buffer,
* but tell userspace how much we've copied so it can determine
* our API version even in a write() call, if it cares.
*/
count = min(count, sizeof(ev));
if (copy_from_user(&ev, buf, count))
return -EFAULT;
if (ev.op != RFKILL_OP_CHANGE && ev.op != RFKILL_OP_CHANGE_ALL)
return -EINVAL;
if (ev.type >= NUM_RFKILL_TYPES)
return -EINVAL;
mutex_lock(&rfkill_global_mutex);
if (ev.op == RFKILL_OP_CHANGE_ALL) {
if (ev.type == RFKILL_TYPE_ALL) {
enum rfkill_type i;
for (i = 0; i < NUM_RFKILL_TYPES; i++)
rfkill_global_states[i].cur = ev.soft;
} else {
rfkill_global_states[ev.type].cur = ev.soft;
}
}
list_for_each_entry(rfkill, &rfkill_list, node) {
if (rfkill->idx != ev.idx && ev.op != RFKILL_OP_CHANGE_ALL)
continue;
if (rfkill->type != ev.type && ev.type != RFKILL_TYPE_ALL)
continue;
rfkill_set_block(rfkill, ev.soft);
}
mutex_unlock(&rfkill_global_mutex);
return count;
}
static int rfkill_fop_release(struct inode *inode, struct file *file)
{
struct rfkill_data *data = file->private_data;
struct rfkill_int_event *ev, *tmp;
mutex_lock(&rfkill_global_mutex);
list_del(&data->list);
mutex_unlock(&rfkill_global_mutex);
mutex_destroy(&data->mtx);
list_for_each_entry_safe(ev, tmp, &data->events, list)
kfree(ev);
#ifdef CONFIG_RFKILL_INPUT
if (data->input_handler)
if (atomic_dec_return(&rfkill_input_disabled) == 0)
printk(KERN_DEBUG "rfkill: input handler enabled\n");
#endif
kfree(data);
return 0;
}
#ifdef CONFIG_RFKILL_INPUT
static long rfkill_fop_ioctl(struct file *file, unsigned int cmd,
unsigned long arg)
{
struct rfkill_data *data = file->private_data;
if (_IOC_TYPE(cmd) != RFKILL_IOC_MAGIC)
return -ENOSYS;
if (_IOC_NR(cmd) != RFKILL_IOC_NOINPUT)
return -ENOSYS;
mutex_lock(&data->mtx);
if (!data->input_handler) {
if (atomic_inc_return(&rfkill_input_disabled) == 1)
printk(KERN_DEBUG "rfkill: input handler disabled\n");
data->input_handler = true;
}
mutex_unlock(&data->mtx);
return 0;
}
#endif
static const struct file_operations rfkill_fops = {
.owner = THIS_MODULE,
.open = rfkill_fop_open,
.read = rfkill_fop_read,
.write = rfkill_fop_write,
.poll = rfkill_fop_poll,
.release = rfkill_fop_release,
#ifdef CONFIG_RFKILL_INPUT
.unlocked_ioctl = rfkill_fop_ioctl,
.compat_ioctl = rfkill_fop_ioctl,
#endif
.llseek = no_llseek,
};
static struct miscdevice rfkill_miscdev = {
.name = "rfkill",
.fops = &rfkill_fops,
.minor = MISC_DYNAMIC_MINOR,
};
static int __init rfkill_init(void)
{
int error;
int i;
for (i = 0; i < NUM_RFKILL_TYPES; i++)
rfkill_global_states[i].cur = !rfkill_default_state;
error = class_register(&rfkill_class);
if (error)
goto out;
error = misc_register(&rfkill_miscdev);
if (error) {
class_unregister(&rfkill_class);
goto out;
}
#ifdef CONFIG_RFKILL_INPUT
error = rfkill_handler_init();
if (error) {
misc_deregister(&rfkill_miscdev);
class_unregister(&rfkill_class);
goto out;
}
#endif
out:
return error;
}
subsys_initcall(rfkill_init);
static void __exit rfkill_exit(void)
{
#ifdef CONFIG_RFKILL_INPUT
rfkill_handler_exit();
#endif
misc_deregister(&rfkill_miscdev);
class_unregister(&rfkill_class);
}
module_exit(rfkill_exit);