diff options
| -rw-r--r-- | drivers/rtc/rtc-dev.c | 58 | ||||
| -rw-r--r-- | include/linux/rtc.h | 17 | 
2 files changed, 55 insertions, 20 deletions
diff --git a/drivers/rtc/rtc-dev.c b/drivers/rtc/rtc-dev.c index 0114a78b7cb..0a870b7e5c3 100644 --- a/drivers/rtc/rtc-dev.c +++ b/drivers/rtc/rtc-dev.c @@ -209,7 +209,7 @@ static unsigned int rtc_dev_poll(struct file *file, poll_table *wait)  	return (data != 0) ? (POLLIN | POLLRDNORM) : 0;  } -static int rtc_dev_ioctl(struct inode *inode, struct file *file, +static long rtc_dev_ioctl(struct file *file,  		unsigned int cmd, unsigned long arg)  {  	int err = 0; @@ -219,6 +219,10 @@ static int rtc_dev_ioctl(struct inode *inode, struct file *file,  	struct rtc_wkalrm alarm;  	void __user *uarg = (void __user *) arg; +	err = mutex_lock_interruptible(&rtc->ops_lock); +	if (err) +		return -EBUSY; +  	/* check that the calling task has appropriate permissions  	 * for certain ioctls. doing this check here is useful  	 * to avoid duplicate code in each driver. @@ -227,26 +231,31 @@ static int rtc_dev_ioctl(struct inode *inode, struct file *file,  	case RTC_EPOCH_SET:  	case RTC_SET_TIME:  		if (!capable(CAP_SYS_TIME)) -			return -EACCES; +			err = -EACCES;  		break;  	case RTC_IRQP_SET:  		if (arg > rtc->max_user_freq && !capable(CAP_SYS_RESOURCE)) -			return -EACCES; +			err = -EACCES;  		break;  	case RTC_PIE_ON:  		if (rtc->irq_freq > rtc->max_user_freq &&  				!capable(CAP_SYS_RESOURCE)) -			return -EACCES; +			err = -EACCES;  		break;  	} +	if (err) +		goto done; +  	/* try the driver's ioctl interface */  	if (ops->ioctl) {  		err = ops->ioctl(rtc->dev.parent, cmd, arg); -		if (err != -ENOIOCTLCMD) +		if (err != -ENOIOCTLCMD) { +			mutex_unlock(&rtc->ops_lock);  			return err; +		}  	}  	/* if the driver does not provide the ioctl interface @@ -265,15 +274,19 @@ static int rtc_dev_ioctl(struct inode *inode, struct file *file,  	switch (cmd) {  	case RTC_ALM_READ: +		mutex_unlock(&rtc->ops_lock); +  		err = rtc_read_alarm(rtc, &alarm);  		if (err < 0)  			return err;  		if (copy_to_user(uarg, &alarm.time, sizeof(tm))) -			return -EFAULT; -		break; +			err = -EFAULT; +		return err;  	case RTC_ALM_SET: +		mutex_unlock(&rtc->ops_lock); +  		if (copy_from_user(&alarm.time, uarg, sizeof(tm)))  			return -EFAULT; @@ -321,24 +334,26 @@ static int rtc_dev_ioctl(struct inode *inode, struct file *file,  			}  		} -		err = rtc_set_alarm(rtc, &alarm); -		break; +		return rtc_set_alarm(rtc, &alarm);  	case RTC_RD_TIME: +		mutex_unlock(&rtc->ops_lock); +  		err = rtc_read_time(rtc, &tm);  		if (err < 0)  			return err;  		if (copy_to_user(uarg, &tm, sizeof(tm))) -			return -EFAULT; -		break; +			err = -EFAULT; +		return err;  	case RTC_SET_TIME: +		mutex_unlock(&rtc->ops_lock); +  		if (copy_from_user(&tm, uarg, sizeof(tm)))  			return -EFAULT; -		err = rtc_set_time(rtc, &tm); -		break; +		return rtc_set_time(rtc, &tm);  	case RTC_PIE_ON:  		err = rtc_irq_set_state(rtc, NULL, 1); @@ -376,34 +391,37 @@ static int rtc_dev_ioctl(struct inode *inode, struct file *file,  		break;  #endif  	case RTC_WKALM_SET: +		mutex_unlock(&rtc->ops_lock);  		if (copy_from_user(&alarm, uarg, sizeof(alarm)))  			return -EFAULT; -		err = rtc_set_alarm(rtc, &alarm); -		break; +		return rtc_set_alarm(rtc, &alarm);  	case RTC_WKALM_RD: +		mutex_unlock(&rtc->ops_lock);  		err = rtc_read_alarm(rtc, &alarm);  		if (err < 0)  			return err;  		if (copy_to_user(uarg, &alarm, sizeof(alarm))) -			return -EFAULT; -		break; +			err = -EFAULT; +		return err;  #ifdef CONFIG_RTC_INTF_DEV_UIE_EMUL  	case RTC_UIE_OFF:  		clear_uie(rtc); -		return 0; +		break;  	case RTC_UIE_ON: -		return set_uie(rtc); +		err = set_uie(rtc);  #endif  	default:  		err = -ENOTTY;  		break;  	} +done: +	mutex_unlock(&rtc->ops_lock);  	return err;  } @@ -432,7 +450,7 @@ static const struct file_operations rtc_dev_fops = {  	.llseek		= no_llseek,  	.read		= rtc_dev_read,  	.poll		= rtc_dev_poll, -	.ioctl		= rtc_dev_ioctl, +	.unlocked_ioctl	= rtc_dev_ioctl,  	.open		= rtc_dev_open,  	.release	= rtc_dev_release,  	.fasync		= rtc_dev_fasync, diff --git a/include/linux/rtc.h b/include/linux/rtc.h index f2d0d152772..b01fe004cb5 100644 --- a/include/linux/rtc.h +++ b/include/linux/rtc.h @@ -115,6 +115,23 @@ extern void rtc_time_to_tm(unsigned long time, struct rtc_time *tm);  extern struct class *rtc_class; +/* + * For these RTC methods the device parameter is the physical device + * on whatever bus holds the hardware (I2C, Platform, SPI, etc), which + * was passed to rtc_device_register().  Its driver_data normally holds + * device state, including the rtc_device pointer for the RTC. + * + * Most of these methods are called with rtc_device.ops_lock held, + * through the rtc_*(struct rtc_device *, ...) calls. + * + * The (current) exceptions are mostly filesystem hooks: + *   - the proc() hook for procfs + *   - non-ioctl() chardev hooks:  open(), release(), read_callback() + *   - periodic irq calls:  irq_set_state(), irq_set_freq() + * + * REVISIT those periodic irq calls *do* have ops_lock when they're + * issued through ioctl() ... + */  struct rtc_class_ops {  	int (*open)(struct device *);  	void (*release)(struct device *);  |