linux/drivers/watchdog/shwdt.c
Kees Cook e99e88a9d2 treewide: setup_timer() -> timer_setup()
This converts all remaining cases of the old setup_timer() API into using
timer_setup(), where the callback argument is the structure already
holding the struct timer_list. These should have no behavioral changes,
since they just change which pointer is passed into the callback with
the same available pointers after conversion. It handles the following
examples, in addition to some other variations.

Casting from unsigned long:

    void my_callback(unsigned long data)
    {
        struct something *ptr = (struct something *)data;
    ...
    }
    ...
    setup_timer(&ptr->my_timer, my_callback, ptr);

and forced object casts:

    void my_callback(struct something *ptr)
    {
    ...
    }
    ...
    setup_timer(&ptr->my_timer, my_callback, (unsigned long)ptr);

become:

    void my_callback(struct timer_list *t)
    {
        struct something *ptr = from_timer(ptr, t, my_timer);
    ...
    }
    ...
    timer_setup(&ptr->my_timer, my_callback, 0);

Direct function assignments:

    void my_callback(unsigned long data)
    {
        struct something *ptr = (struct something *)data;
    ...
    }
    ...
    ptr->my_timer.function = my_callback;

have a temporary cast added, along with converting the args:

    void my_callback(struct timer_list *t)
    {
        struct something *ptr = from_timer(ptr, t, my_timer);
    ...
    }
    ...
    ptr->my_timer.function = (TIMER_FUNC_TYPE)my_callback;

And finally, callbacks without a data assignment:

    void my_callback(unsigned long data)
    {
    ...
    }
    ...
    setup_timer(&ptr->my_timer, my_callback, 0);

have their argument renamed to verify they're unused during conversion:

    void my_callback(struct timer_list *unused)
    {
    ...
    }
    ...
    timer_setup(&ptr->my_timer, my_callback, 0);

The conversion is done with the following Coccinelle script:

spatch --very-quiet --all-includes --include-headers \
	-I ./arch/x86/include -I ./arch/x86/include/generated \
	-I ./include -I ./arch/x86/include/uapi \
	-I ./arch/x86/include/generated/uapi -I ./include/uapi \
	-I ./include/generated/uapi --include ./include/linux/kconfig.h \
	--dir . \
	--cocci-file ~/src/data/timer_setup.cocci

@fix_address_of@
expression e;
@@

 setup_timer(
-&(e)
+&e
 , ...)

// Update any raw setup_timer() usages that have a NULL callback, but
// would otherwise match change_timer_function_usage, since the latter
// will update all function assignments done in the face of a NULL
// function initialization in setup_timer().
@change_timer_function_usage_NULL@
expression _E;
identifier _timer;
type _cast_data;
@@

(
-setup_timer(&_E->_timer, NULL, _E);
+timer_setup(&_E->_timer, NULL, 0);
|
-setup_timer(&_E->_timer, NULL, (_cast_data)_E);
+timer_setup(&_E->_timer, NULL, 0);
|
-setup_timer(&_E._timer, NULL, &_E);
+timer_setup(&_E._timer, NULL, 0);
|
-setup_timer(&_E._timer, NULL, (_cast_data)&_E);
+timer_setup(&_E._timer, NULL, 0);
)

@change_timer_function_usage@
expression _E;
identifier _timer;
struct timer_list _stl;
identifier _callback;
type _cast_func, _cast_data;
@@

(
-setup_timer(&_E->_timer, _callback, _E);
+timer_setup(&_E->_timer, _callback, 0);
|
-setup_timer(&_E->_timer, &_callback, _E);
+timer_setup(&_E->_timer, _callback, 0);
|
-setup_timer(&_E->_timer, _callback, (_cast_data)_E);
+timer_setup(&_E->_timer, _callback, 0);
|
-setup_timer(&_E->_timer, &_callback, (_cast_data)_E);
+timer_setup(&_E->_timer, _callback, 0);
|
-setup_timer(&_E->_timer, (_cast_func)_callback, _E);
+timer_setup(&_E->_timer, _callback, 0);
|
-setup_timer(&_E->_timer, (_cast_func)&_callback, _E);
+timer_setup(&_E->_timer, _callback, 0);
|
-setup_timer(&_E->_timer, (_cast_func)_callback, (_cast_data)_E);
+timer_setup(&_E->_timer, _callback, 0);
|
-setup_timer(&_E->_timer, (_cast_func)&_callback, (_cast_data)_E);
+timer_setup(&_E->_timer, _callback, 0);
|
-setup_timer(&_E._timer, _callback, (_cast_data)_E);
+timer_setup(&_E._timer, _callback, 0);
|
-setup_timer(&_E._timer, _callback, (_cast_data)&_E);
+timer_setup(&_E._timer, _callback, 0);
|
-setup_timer(&_E._timer, &_callback, (_cast_data)_E);
+timer_setup(&_E._timer, _callback, 0);
|
-setup_timer(&_E._timer, &_callback, (_cast_data)&_E);
+timer_setup(&_E._timer, _callback, 0);
|
-setup_timer(&_E._timer, (_cast_func)_callback, (_cast_data)_E);
+timer_setup(&_E._timer, _callback, 0);
|
-setup_timer(&_E._timer, (_cast_func)_callback, (_cast_data)&_E);
+timer_setup(&_E._timer, _callback, 0);
|
-setup_timer(&_E._timer, (_cast_func)&_callback, (_cast_data)_E);
+timer_setup(&_E._timer, _callback, 0);
|
-setup_timer(&_E._timer, (_cast_func)&_callback, (_cast_data)&_E);
+timer_setup(&_E._timer, _callback, 0);
|
 _E->_timer@_stl.function = _callback;
|
 _E->_timer@_stl.function = &_callback;
|
 _E->_timer@_stl.function = (_cast_func)_callback;
|
 _E->_timer@_stl.function = (_cast_func)&_callback;
|
 _E._timer@_stl.function = _callback;
|
 _E._timer@_stl.function = &_callback;
|
 _E._timer@_stl.function = (_cast_func)_callback;
|
 _E._timer@_stl.function = (_cast_func)&_callback;
)

// callback(unsigned long arg)
@change_callback_handle_cast
 depends on change_timer_function_usage@
identifier change_timer_function_usage._callback;
identifier change_timer_function_usage._timer;
type _origtype;
identifier _origarg;
type _handletype;
identifier _handle;
@@

 void _callback(
-_origtype _origarg
+struct timer_list *t
 )
 {
(
	... when != _origarg
	_handletype *_handle =
-(_handletype *)_origarg;
+from_timer(_handle, t, _timer);
	... when != _origarg
|
	... when != _origarg
	_handletype *_handle =
-(void *)_origarg;
+from_timer(_handle, t, _timer);
	... when != _origarg
|
	... when != _origarg
	_handletype *_handle;
	... when != _handle
	_handle =
-(_handletype *)_origarg;
+from_timer(_handle, t, _timer);
	... when != _origarg
|
	... when != _origarg
	_handletype *_handle;
	... when != _handle
	_handle =
-(void *)_origarg;
+from_timer(_handle, t, _timer);
	... when != _origarg
)
 }

// callback(unsigned long arg) without existing variable
@change_callback_handle_cast_no_arg
 depends on change_timer_function_usage &&
                     !change_callback_handle_cast@
identifier change_timer_function_usage._callback;
identifier change_timer_function_usage._timer;
type _origtype;
identifier _origarg;
type _handletype;
@@

 void _callback(
-_origtype _origarg
+struct timer_list *t
 )
 {
+	_handletype *_origarg = from_timer(_origarg, t, _timer);
+
	... when != _origarg
-	(_handletype *)_origarg
+	_origarg
	... when != _origarg
 }

// Avoid already converted callbacks.
@match_callback_converted
 depends on change_timer_function_usage &&
            !change_callback_handle_cast &&
	    !change_callback_handle_cast_no_arg@
identifier change_timer_function_usage._callback;
identifier t;
@@

 void _callback(struct timer_list *t)
 { ... }

// callback(struct something *handle)
@change_callback_handle_arg
 depends on change_timer_function_usage &&
	    !match_callback_converted &&
            !change_callback_handle_cast &&
            !change_callback_handle_cast_no_arg@
identifier change_timer_function_usage._callback;
identifier change_timer_function_usage._timer;
type _handletype;
identifier _handle;
@@

 void _callback(
-_handletype *_handle
+struct timer_list *t
 )
 {
+	_handletype *_handle = from_timer(_handle, t, _timer);
	...
 }

// If change_callback_handle_arg ran on an empty function, remove
// the added handler.
@unchange_callback_handle_arg
 depends on change_timer_function_usage &&
	    change_callback_handle_arg@
identifier change_timer_function_usage._callback;
identifier change_timer_function_usage._timer;
type _handletype;
identifier _handle;
identifier t;
@@

 void _callback(struct timer_list *t)
 {
-	_handletype *_handle = from_timer(_handle, t, _timer);
 }

// We only want to refactor the setup_timer() data argument if we've found
// the matching callback. This undoes changes in change_timer_function_usage.
@unchange_timer_function_usage
 depends on change_timer_function_usage &&
            !change_callback_handle_cast &&
            !change_callback_handle_cast_no_arg &&
	    !change_callback_handle_arg@
expression change_timer_function_usage._E;
identifier change_timer_function_usage._timer;
identifier change_timer_function_usage._callback;
type change_timer_function_usage._cast_data;
@@

(
-timer_setup(&_E->_timer, _callback, 0);
+setup_timer(&_E->_timer, _callback, (_cast_data)_E);
|
-timer_setup(&_E._timer, _callback, 0);
+setup_timer(&_E._timer, _callback, (_cast_data)&_E);
)

// If we fixed a callback from a .function assignment, fix the
// assignment cast now.
@change_timer_function_assignment
 depends on change_timer_function_usage &&
            (change_callback_handle_cast ||
             change_callback_handle_cast_no_arg ||
             change_callback_handle_arg)@
expression change_timer_function_usage._E;
identifier change_timer_function_usage._timer;
identifier change_timer_function_usage._callback;
type _cast_func;
typedef TIMER_FUNC_TYPE;
@@

(
 _E->_timer.function =
-_callback
+(TIMER_FUNC_TYPE)_callback
 ;
|
 _E->_timer.function =
-&_callback
+(TIMER_FUNC_TYPE)_callback
 ;
|
 _E->_timer.function =
-(_cast_func)_callback;
+(TIMER_FUNC_TYPE)_callback
 ;
|
 _E->_timer.function =
-(_cast_func)&_callback
+(TIMER_FUNC_TYPE)_callback
 ;
|
 _E._timer.function =
-_callback
+(TIMER_FUNC_TYPE)_callback
 ;
|
 _E._timer.function =
-&_callback;
+(TIMER_FUNC_TYPE)_callback
 ;
|
 _E._timer.function =
-(_cast_func)_callback
+(TIMER_FUNC_TYPE)_callback
 ;
|
 _E._timer.function =
-(_cast_func)&_callback
+(TIMER_FUNC_TYPE)_callback
 ;
)

// Sometimes timer functions are called directly. Replace matched args.
@change_timer_function_calls
 depends on change_timer_function_usage &&
            (change_callback_handle_cast ||
             change_callback_handle_cast_no_arg ||
             change_callback_handle_arg)@
expression _E;
identifier change_timer_function_usage._timer;
identifier change_timer_function_usage._callback;
type _cast_data;
@@

 _callback(
(
-(_cast_data)_E
+&_E->_timer
|
-(_cast_data)&_E
+&_E._timer
|
-_E
+&_E->_timer
)
 )

// If a timer has been configured without a data argument, it can be
// converted without regard to the callback argument, since it is unused.
@match_timer_function_unused_data@
expression _E;
identifier _timer;
identifier _callback;
@@

(
-setup_timer(&_E->_timer, _callback, 0);
+timer_setup(&_E->_timer, _callback, 0);
|
-setup_timer(&_E->_timer, _callback, 0L);
+timer_setup(&_E->_timer, _callback, 0);
|
-setup_timer(&_E->_timer, _callback, 0UL);
+timer_setup(&_E->_timer, _callback, 0);
|
-setup_timer(&_E._timer, _callback, 0);
+timer_setup(&_E._timer, _callback, 0);
|
-setup_timer(&_E._timer, _callback, 0L);
+timer_setup(&_E._timer, _callback, 0);
|
-setup_timer(&_E._timer, _callback, 0UL);
+timer_setup(&_E._timer, _callback, 0);
|
-setup_timer(&_timer, _callback, 0);
+timer_setup(&_timer, _callback, 0);
|
-setup_timer(&_timer, _callback, 0L);
+timer_setup(&_timer, _callback, 0);
|
-setup_timer(&_timer, _callback, 0UL);
+timer_setup(&_timer, _callback, 0);
|
-setup_timer(_timer, _callback, 0);
+timer_setup(_timer, _callback, 0);
|
-setup_timer(_timer, _callback, 0L);
+timer_setup(_timer, _callback, 0);
|
-setup_timer(_timer, _callback, 0UL);
+timer_setup(_timer, _callback, 0);
)

@change_callback_unused_data
 depends on match_timer_function_unused_data@
identifier match_timer_function_unused_data._callback;
type _origtype;
identifier _origarg;
@@

 void _callback(
-_origtype _origarg
+struct timer_list *unused
 )
 {
	... when != _origarg
 }

Signed-off-by: Kees Cook <keescook@chromium.org>
2017-11-21 15:57:07 -08:00

351 lines
9.1 KiB
C

/*
* drivers/watchdog/shwdt.c
*
* Watchdog driver for integrated watchdog in the SuperH processors.
*
* Copyright (C) 2001 - 2012 Paul Mundt <lethal@linux-sh.org>
*
* 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.
*
* 14-Dec-2001 Matt Domsch <Matt_Domsch@dell.com>
* Added nowayout module option to override CONFIG_WATCHDOG_NOWAYOUT
*
* 19-Apr-2002 Rob Radez <rob@osinvestor.com>
* Added expect close support, made emulated timeout runtime changeable
* general cleanups, add some ioctls
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/platform_device.h>
#include <linux/init.h>
#include <linux/types.h>
#include <linux/spinlock.h>
#include <linux/watchdog.h>
#include <linux/pm_runtime.h>
#include <linux/fs.h>
#include <linux/mm.h>
#include <linux/slab.h>
#include <linux/io.h>
#include <linux/clk.h>
#include <linux/err.h>
#include <asm/watchdog.h>
#define DRV_NAME "sh-wdt"
/*
* Default clock division ratio is 5.25 msecs. For an additional table of
* values, consult the asm-sh/watchdog.h. Overload this at module load
* time.
*
* In order for this to work reliably we need to have HZ set to 1000 or
* something quite higher than 100 (or we need a proper high-res timer
* implementation that will deal with this properly), otherwise the 10ms
* resolution of a jiffy is enough to trigger the overflow. For things like
* the SH-4 and SH-5, this isn't necessarily that big of a problem, though
* for the SH-2 and SH-3, this isn't recommended unless the WDT is absolutely
* necssary.
*
* As a result of this timing problem, the only modes that are particularly
* feasible are the 4096 and the 2048 divisors, which yield 5.25 and 2.62ms
* overflow periods respectively.
*
* Also, since we can't really expect userspace to be responsive enough
* before the overflow happens, we maintain two separate timers .. One in
* the kernel for clearing out WOVF every 2ms or so (again, this depends on
* HZ == 1000), and another for monitoring userspace writes to the WDT device.
*
* As such, we currently use a configurable heartbeat interval which defaults
* to 30s. In this case, the userspace daemon is only responsible for periodic
* writes to the device before the next heartbeat is scheduled. If the daemon
* misses its deadline, the kernel timer will allow the WDT to overflow.
*/
static int clock_division_ratio = WTCSR_CKS_4096;
#define next_ping_period(cks) (jiffies + msecs_to_jiffies(cks - 4))
#define WATCHDOG_HEARTBEAT 30 /* 30 sec default heartbeat */
static int heartbeat = WATCHDOG_HEARTBEAT; /* in seconds */
static bool nowayout = WATCHDOG_NOWAYOUT;
static unsigned long next_heartbeat;
struct sh_wdt {
void __iomem *base;
struct device *dev;
struct clk *clk;
spinlock_t lock;
struct timer_list timer;
};
static int sh_wdt_start(struct watchdog_device *wdt_dev)
{
struct sh_wdt *wdt = watchdog_get_drvdata(wdt_dev);
unsigned long flags;
u8 csr;
pm_runtime_get_sync(wdt->dev);
clk_enable(wdt->clk);
spin_lock_irqsave(&wdt->lock, flags);
next_heartbeat = jiffies + (heartbeat * HZ);
mod_timer(&wdt->timer, next_ping_period(clock_division_ratio));
csr = sh_wdt_read_csr();
csr |= WTCSR_WT | clock_division_ratio;
sh_wdt_write_csr(csr);
sh_wdt_write_cnt(0);
/*
* These processors have a bit of an inconsistent initialization
* process.. starting with SH-3, RSTS was moved to WTCSR, and the
* RSTCSR register was removed.
*
* On the SH-2 however, in addition with bits being in different
* locations, we must deal with RSTCSR outright..
*/
csr = sh_wdt_read_csr();
csr |= WTCSR_TME;
csr &= ~WTCSR_RSTS;
sh_wdt_write_csr(csr);
#ifdef CONFIG_CPU_SH2
csr = sh_wdt_read_rstcsr();
csr &= ~RSTCSR_RSTS;
sh_wdt_write_rstcsr(csr);
#endif
spin_unlock_irqrestore(&wdt->lock, flags);
return 0;
}
static int sh_wdt_stop(struct watchdog_device *wdt_dev)
{
struct sh_wdt *wdt = watchdog_get_drvdata(wdt_dev);
unsigned long flags;
u8 csr;
spin_lock_irqsave(&wdt->lock, flags);
del_timer(&wdt->timer);
csr = sh_wdt_read_csr();
csr &= ~WTCSR_TME;
sh_wdt_write_csr(csr);
spin_unlock_irqrestore(&wdt->lock, flags);
clk_disable(wdt->clk);
pm_runtime_put_sync(wdt->dev);
return 0;
}
static int sh_wdt_keepalive(struct watchdog_device *wdt_dev)
{
struct sh_wdt *wdt = watchdog_get_drvdata(wdt_dev);
unsigned long flags;
spin_lock_irqsave(&wdt->lock, flags);
next_heartbeat = jiffies + (heartbeat * HZ);
spin_unlock_irqrestore(&wdt->lock, flags);
return 0;
}
static int sh_wdt_set_heartbeat(struct watchdog_device *wdt_dev, unsigned t)
{
struct sh_wdt *wdt = watchdog_get_drvdata(wdt_dev);
unsigned long flags;
if (unlikely(t < 1 || t > 3600)) /* arbitrary upper limit */
return -EINVAL;
spin_lock_irqsave(&wdt->lock, flags);
heartbeat = t;
wdt_dev->timeout = t;
spin_unlock_irqrestore(&wdt->lock, flags);
return 0;
}
static void sh_wdt_ping(struct timer_list *t)
{
struct sh_wdt *wdt = from_timer(wdt, t, timer);
unsigned long flags;
spin_lock_irqsave(&wdt->lock, flags);
if (time_before(jiffies, next_heartbeat)) {
u8 csr;
csr = sh_wdt_read_csr();
csr &= ~WTCSR_IOVF;
sh_wdt_write_csr(csr);
sh_wdt_write_cnt(0);
mod_timer(&wdt->timer, next_ping_period(clock_division_ratio));
} else
dev_warn(wdt->dev, "Heartbeat lost! Will not ping "
"the watchdog\n");
spin_unlock_irqrestore(&wdt->lock, flags);
}
static const struct watchdog_info sh_wdt_info = {
.options = WDIOF_KEEPALIVEPING | WDIOF_SETTIMEOUT |
WDIOF_MAGICCLOSE,
.firmware_version = 1,
.identity = "SH WDT",
};
static const struct watchdog_ops sh_wdt_ops = {
.owner = THIS_MODULE,
.start = sh_wdt_start,
.stop = sh_wdt_stop,
.ping = sh_wdt_keepalive,
.set_timeout = sh_wdt_set_heartbeat,
};
static struct watchdog_device sh_wdt_dev = {
.info = &sh_wdt_info,
.ops = &sh_wdt_ops,
};
static int sh_wdt_probe(struct platform_device *pdev)
{
struct sh_wdt *wdt;
struct resource *res;
int rc;
/*
* As this driver only covers the global watchdog case, reject
* any attempts to register per-CPU watchdogs.
*/
if (pdev->id != -1)
return -EINVAL;
wdt = devm_kzalloc(&pdev->dev, sizeof(struct sh_wdt), GFP_KERNEL);
if (unlikely(!wdt))
return -ENOMEM;
wdt->dev = &pdev->dev;
wdt->clk = devm_clk_get(&pdev->dev, NULL);
if (IS_ERR(wdt->clk)) {
/*
* Clock framework support is optional, continue on
* anyways if we don't find a matching clock.
*/
wdt->clk = NULL;
}
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
wdt->base = devm_ioremap_resource(wdt->dev, res);
if (IS_ERR(wdt->base))
return PTR_ERR(wdt->base);
watchdog_set_nowayout(&sh_wdt_dev, nowayout);
watchdog_set_drvdata(&sh_wdt_dev, wdt);
sh_wdt_dev.parent = &pdev->dev;
spin_lock_init(&wdt->lock);
rc = sh_wdt_set_heartbeat(&sh_wdt_dev, heartbeat);
if (unlikely(rc)) {
/* Default timeout if invalid */
sh_wdt_set_heartbeat(&sh_wdt_dev, WATCHDOG_HEARTBEAT);
dev_warn(&pdev->dev,
"heartbeat value must be 1<=x<=3600, using %d\n",
sh_wdt_dev.timeout);
}
dev_info(&pdev->dev, "configured with heartbeat=%d sec (nowayout=%d)\n",
sh_wdt_dev.timeout, nowayout);
rc = watchdog_register_device(&sh_wdt_dev);
if (unlikely(rc)) {
dev_err(&pdev->dev, "Can't register watchdog (err=%d)\n", rc);
return rc;
}
timer_setup(&wdt->timer, sh_wdt_ping, 0);
wdt->timer.expires = next_ping_period(clock_division_ratio);
dev_info(&pdev->dev, "initialized.\n");
pm_runtime_enable(&pdev->dev);
return 0;
}
static int sh_wdt_remove(struct platform_device *pdev)
{
watchdog_unregister_device(&sh_wdt_dev);
pm_runtime_disable(&pdev->dev);
return 0;
}
static void sh_wdt_shutdown(struct platform_device *pdev)
{
sh_wdt_stop(&sh_wdt_dev);
}
static struct platform_driver sh_wdt_driver = {
.driver = {
.name = DRV_NAME,
},
.probe = sh_wdt_probe,
.remove = sh_wdt_remove,
.shutdown = sh_wdt_shutdown,
};
static int __init sh_wdt_init(void)
{
if (unlikely(clock_division_ratio < 0x5 ||
clock_division_ratio > 0x7)) {
clock_division_ratio = WTCSR_CKS_4096;
pr_info("divisor must be 0x5<=x<=0x7, using %d\n",
clock_division_ratio);
}
return platform_driver_register(&sh_wdt_driver);
}
static void __exit sh_wdt_exit(void)
{
platform_driver_unregister(&sh_wdt_driver);
}
module_init(sh_wdt_init);
module_exit(sh_wdt_exit);
MODULE_AUTHOR("Paul Mundt <lethal@linux-sh.org>");
MODULE_DESCRIPTION("SuperH watchdog driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:" DRV_NAME);
module_param(clock_division_ratio, int, 0);
MODULE_PARM_DESC(clock_division_ratio,
"Clock division ratio. Valid ranges are from 0x5 (1.31ms) "
"to 0x7 (5.25ms). (default=" __MODULE_STRING(WTCSR_CKS_4096) ")");
module_param(heartbeat, int, 0);
MODULE_PARM_DESC(heartbeat,
"Watchdog heartbeat in seconds. (1 <= heartbeat <= 3600, default="
__MODULE_STRING(WATCHDOG_HEARTBEAT) ")");
module_param(nowayout, bool, 0);
MODULE_PARM_DESC(nowayout,
"Watchdog cannot be stopped once started (default="
__MODULE_STRING(WATCHDOG_NOWAYOUT) ")");