linux_dsm_epyc7002/drivers/base/power/power.h
Rafael J. Wysocki 7bf4e594c2 PM / wakeup: Do not fail dev_pm_attach_wake_irq() unnecessarily
Returning an error code from dev_pm_attach_wake_irq() if
device_wakeup_attach_irq() called by it returns an error is
pointless, because the wakeup source used by it may be deleted
by user space via sysfs at any time and in particular right after
dev_pm_attach_wake_irq() has returned.  Moreover, it requires
the callers of dev_pm_attach_wake_irq() to create that wakeup
source via device_wakeup_enable() upfront, but that obviously is
racy with respect to the sysfs-based manipulations of it.

To avoid the race, modify device_wakeup_attach_irq() to check
that the wakeup source it is going to use is there (and return
early otherwise), make it void (as it cannot fail after that
change) and make dev_pm_attach_wake_irq() simply call it for
the device unconditionally.

Tested-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-01-09 13:09:16 +01:00

180 lines
4.9 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#include <linux/pm_qos.h>
static inline void device_pm_init_common(struct device *dev)
{
if (!dev->power.early_init) {
spin_lock_init(&dev->power.lock);
dev->power.qos = NULL;
dev->power.early_init = true;
}
}
#ifdef CONFIG_PM
static inline void pm_runtime_early_init(struct device *dev)
{
dev->power.disable_depth = 1;
device_pm_init_common(dev);
}
extern void pm_runtime_init(struct device *dev);
extern void pm_runtime_reinit(struct device *dev);
extern void pm_runtime_remove(struct device *dev);
#define WAKE_IRQ_DEDICATED_ALLOCATED BIT(0)
#define WAKE_IRQ_DEDICATED_MANAGED BIT(1)
#define WAKE_IRQ_DEDICATED_MASK (WAKE_IRQ_DEDICATED_ALLOCATED | \
WAKE_IRQ_DEDICATED_MANAGED)
struct wake_irq {
struct device *dev;
unsigned int status;
int irq;
};
extern void dev_pm_arm_wake_irq(struct wake_irq *wirq);
extern void dev_pm_disarm_wake_irq(struct wake_irq *wirq);
extern void dev_pm_enable_wake_irq_check(struct device *dev,
bool can_change_status);
extern void dev_pm_disable_wake_irq_check(struct device *dev);
#ifdef CONFIG_PM_SLEEP
extern void device_wakeup_attach_irq(struct device *dev, struct wake_irq *wakeirq);
extern void device_wakeup_detach_irq(struct device *dev);
extern void device_wakeup_arm_wake_irqs(void);
extern void device_wakeup_disarm_wake_irqs(void);
#else
static inline void device_wakeup_attach_irq(struct device *dev,
struct wake_irq *wakeirq) {}
static inline void device_wakeup_detach_irq(struct device *dev)
{
}
static inline void device_wakeup_arm_wake_irqs(void)
{
}
static inline void device_wakeup_disarm_wake_irqs(void)
{
}
#endif /* CONFIG_PM_SLEEP */
/*
* sysfs.c
*/
extern int dpm_sysfs_add(struct device *dev);
extern void dpm_sysfs_remove(struct device *dev);
extern void rpm_sysfs_remove(struct device *dev);
extern int wakeup_sysfs_add(struct device *dev);
extern void wakeup_sysfs_remove(struct device *dev);
extern int pm_qos_sysfs_add_resume_latency(struct device *dev);
extern void pm_qos_sysfs_remove_resume_latency(struct device *dev);
extern int pm_qos_sysfs_add_flags(struct device *dev);
extern void pm_qos_sysfs_remove_flags(struct device *dev);
extern int pm_qos_sysfs_add_latency_tolerance(struct device *dev);
extern void pm_qos_sysfs_remove_latency_tolerance(struct device *dev);
#else /* CONFIG_PM */
static inline void pm_runtime_early_init(struct device *dev)
{
device_pm_init_common(dev);
}
static inline void pm_runtime_init(struct device *dev) {}
static inline void pm_runtime_reinit(struct device *dev) {}
static inline void pm_runtime_remove(struct device *dev) {}
static inline int dpm_sysfs_add(struct device *dev) { return 0; }
static inline void dpm_sysfs_remove(struct device *dev) {}
static inline void rpm_sysfs_remove(struct device *dev) {}
static inline int wakeup_sysfs_add(struct device *dev) { return 0; }
static inline void wakeup_sysfs_remove(struct device *dev) {}
static inline int pm_qos_sysfs_add(struct device *dev) { return 0; }
static inline void pm_qos_sysfs_remove(struct device *dev) {}
static inline void dev_pm_arm_wake_irq(struct wake_irq *wirq)
{
}
static inline void dev_pm_disarm_wake_irq(struct wake_irq *wirq)
{
}
static inline void dev_pm_enable_wake_irq_check(struct device *dev,
bool can_change_status)
{
}
static inline void dev_pm_disable_wake_irq_check(struct device *dev)
{
}
#endif
#ifdef CONFIG_PM_SLEEP
/* kernel/power/main.c */
extern int pm_async_enabled;
/* drivers/base/power/main.c */
extern struct list_head dpm_list; /* The active device list */
static inline struct device *to_device(struct list_head *entry)
{
return container_of(entry, struct device, power.entry);
}
extern void device_pm_sleep_init(struct device *dev);
extern void device_pm_add(struct device *);
extern void device_pm_remove(struct device *);
extern void device_pm_move_before(struct device *, struct device *);
extern void device_pm_move_after(struct device *, struct device *);
extern void device_pm_move_last(struct device *);
extern void device_pm_check_callbacks(struct device *dev);
static inline bool device_pm_initialized(struct device *dev)
{
return dev->power.in_dpm_list;
}
#else /* !CONFIG_PM_SLEEP */
static inline void device_pm_sleep_init(struct device *dev) {}
static inline void device_pm_add(struct device *dev) {}
static inline void device_pm_remove(struct device *dev)
{
pm_runtime_remove(dev);
}
static inline void device_pm_move_before(struct device *deva,
struct device *devb) {}
static inline void device_pm_move_after(struct device *deva,
struct device *devb) {}
static inline void device_pm_move_last(struct device *dev) {}
static inline void device_pm_check_callbacks(struct device *dev) {}
static inline bool device_pm_initialized(struct device *dev)
{
return device_is_registered(dev);
}
#endif /* !CONFIG_PM_SLEEP */
static inline void device_pm_init(struct device *dev)
{
device_pm_init_common(dev);
device_pm_sleep_init(dev);
pm_runtime_init(dev);
}