From: Arnd Bergmann Date: Mon, 22 Mar 2010 19:55:11 +0000 (+0100) Subject: hpet: kill BKL, add compat_ioctl X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=54066a57c584ee8ce767053116fc4943ed1168b5;p=linux-beck.git hpet: kill BKL, add compat_ioctl hpet uses the big kernel lock in its ioctl and open functions. Replace this with a private mutex to be sure. Since we're already touching the ioctl function, add the compat_ioctl version as well -- all commands except HPET_INFO are compatible and that one is easy to add. Signed-off-by: Arnd Bergmann Cc: Clemens Ladisch Cc: Bob Picco --- diff --git a/drivers/char/hpet.c b/drivers/char/hpet.c index a0a1829d3198..a4eee324eb1e 100644 --- a/drivers/char/hpet.c +++ b/drivers/char/hpet.c @@ -30,6 +30,7 @@ #include #include #include +#include #include #include @@ -67,6 +68,7 @@ #define read_counter(MC) readl(MC) #endif +static DEFINE_MUTEX(hpet_mutex); /* replaces BKL */ static u32 hpet_nhpet, hpet_max_freq = HPET_USER_FREQ; /* This clocksource driver currently only works on ia64 */ @@ -250,7 +252,7 @@ static int hpet_open(struct inode *inode, struct file *file) if (file->f_mode & FMODE_WRITE) return -EINVAL; - lock_kernel(); + mutex_lock(&hpet_mutex); spin_lock_irq(&hpet_lock); for (devp = NULL, hpetp = hpets; hpetp && !devp; hpetp = hpetp->hp_next) @@ -264,7 +266,7 @@ static int hpet_open(struct inode *inode, struct file *file) if (!devp) { spin_unlock_irq(&hpet_lock); - unlock_kernel(); + mutex_unlock(&hpet_mutex); return -EBUSY; } @@ -272,7 +274,7 @@ static int hpet_open(struct inode *inode, struct file *file) devp->hd_irqdata = 0; devp->hd_flags |= HPET_OPEN; spin_unlock_irq(&hpet_lock); - unlock_kernel(); + mutex_unlock(&hpet_mutex); hpet_timer_set_irq(devp); @@ -429,22 +431,6 @@ static int hpet_release(struct inode *inode, struct file *file) return 0; } -static int hpet_ioctl_common(struct hpet_dev *, int, unsigned long, int); - -static long hpet_ioctl(struct file *file, unsigned int cmd, - unsigned long arg) -{ - struct hpet_dev *devp; - int ret; - - devp = file->private_data; - lock_kernel(); - ret = hpet_ioctl_common(devp, cmd, arg, 0); - unlock_kernel(); - - return ret; -} - static int hpet_ioctl_ieon(struct hpet_dev *devp) { struct hpet_timer __iomem *timer; @@ -553,7 +539,8 @@ static inline unsigned long hpet_time_div(struct hpets *hpets, } static int -hpet_ioctl_common(struct hpet_dev *devp, int cmd, unsigned long arg, int kernel) +hpet_ioctl_common(struct hpet_dev *devp, int cmd, unsigned long arg, + struct hpet_info *info) { struct hpet_timer __iomem *timer; struct hpet __iomem *hpet; @@ -594,23 +581,15 @@ hpet_ioctl_common(struct hpet_dev *devp, int cmd, unsigned long arg, int kernel) break; case HPET_INFO: { - struct hpet_info info; - if (devp->hd_ireqfreq) - info.hi_ireqfreq = + info->hi_ireqfreq = hpet_time_div(hpetp, devp->hd_ireqfreq); else - info.hi_ireqfreq = 0; - info.hi_flags = + info->hi_ireqfreq = 0; + info->hi_flags = readq(&timer->hpet_config) & Tn_PER_INT_CAP_MASK; - info.hi_hpet = hpetp->hp_which; - info.hi_timer = devp - hpetp->hp_dev; - if (kernel) - memcpy((void *)arg, &info, sizeof(info)); - else - if (copy_to_user((void __user *)arg, &info, - sizeof(info))) - err = -EFAULT; + info->hi_hpet = hpetp->hp_which; + info->hi_timer = devp - hpetp->hp_dev; break; } case HPET_EPI: @@ -636,7 +615,7 @@ hpet_ioctl_common(struct hpet_dev *devp, int cmd, unsigned long arg, int kernel) devp->hd_flags &= ~HPET_PERIODIC; break; case HPET_IRQFREQ: - if (!kernel && (arg > hpet_max_freq) && + if ((arg > hpet_max_freq) && !capable(CAP_SYS_RESOURCE)) { err = -EACCES; break; @@ -653,12 +632,63 @@ hpet_ioctl_common(struct hpet_dev *devp, int cmd, unsigned long arg, int kernel) return err; } +static long +hpet_ioctl(struct file *file, unsigned int cmd, unsigned long arg) +{ + struct hpet_info info; + int err; + + mutex_lock(&hpet_mutex); + err = hpet_ioctl_common(file->private_data, cmd, arg, &info); + mutex_unlock(&hpet_mutex); + + if ((cmd == HPET_INFO) && !err && + (copy_to_user((void __user *)arg, &info, sizeof(info)))) + err = -EFAULT; + + return err; +} + +#ifdef CONFIG_COMPAT +struct compat_hpet_info { + compat_ulong_t hi_ireqfreq; /* Hz */ + compat_ulong_t hi_flags; /* information */ + unsigned short hi_hpet; + unsigned short hi_timer; +}; + +static long +hpet_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg) +{ + struct hpet_info info; + int err; + + mutex_lock(&hpet_mutex); + err = hpet_ioctl_common(file->private_data, cmd, arg, &info); + mutex_unlock(&hpet_mutex); + + if ((cmd == HPET_INFO) && !err) { + struct compat_hpet_info __user *u = compat_ptr(arg); + if (put_user(info.hi_ireqfreq, &u->hi_ireqfreq) || + put_user(info.hi_flags, &u->hi_flags) || + put_user(info.hi_hpet, &u->hi_hpet) || + put_user(info.hi_timer, &u->hi_timer)) + err = -EFAULT; + } + + return err; +} +#endif + static const struct file_operations hpet_fops = { .owner = THIS_MODULE, .llseek = no_llseek, .read = hpet_read, .poll = hpet_poll, .unlocked_ioctl = hpet_ioctl, +#ifdef CONFIG_COMPAT + .compat_ioctl = hpet_compat_ioctl, +#endif .open = hpet_open, .release = hpet_release, .fasync = hpet_fasync,