diff options
author | James Bottomley <James.Bottomley@HansenPartnership.com> | 2009-06-12 10:02:03 -0500 |
---|---|---|
committer | James Bottomley <James.Bottomley@HansenPartnership.com> | 2009-06-12 10:02:03 -0500 |
commit | 82681a318f9f028ea64e61f24bbd9ac535531921 (patch) | |
tree | 529b6a5b4fd040fb54b7672b1a224ebd47445876 /drivers/char/tty_ioctl.c | |
parent | 3860c97bd60a4525bb62eb90e3e7d2f02662ac59 (diff) | |
parent | 8ebf975608aaebd7feb33d77f07ba21a6380e086 (diff) |
[SCSI] Merge branch 'linus'
Conflicts:
drivers/message/fusion/mptsas.c
fixed up conflict between req->data_len accessors and mptsas driver updates.
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Diffstat (limited to 'drivers/char/tty_ioctl.c')
-rw-r--r-- | drivers/char/tty_ioctl.c | 88 |
1 files changed, 59 insertions, 29 deletions
diff --git a/drivers/char/tty_ioctl.c b/drivers/char/tty_ioctl.c index 6f4c7d0a53b..8116bb1c8f8 100644 --- a/drivers/char/tty_ioctl.c +++ b/drivers/char/tty_ioctl.c @@ -97,14 +97,19 @@ EXPORT_SYMBOL(tty_driver_flush_buffer); * @tty: terminal * * Indicate that a tty should stop transmitting data down the stack. + * Takes the termios mutex to protect against parallel throttle/unthrottle + * and also to ensure the driver can consistently reference its own + * termios data at this point when implementing software flow control. */ void tty_throttle(struct tty_struct *tty) { + mutex_lock(&tty->termios_mutex); /* check TTY_THROTTLED first so it indicates our state */ if (!test_and_set_bit(TTY_THROTTLED, &tty->flags) && tty->ops->throttle) tty->ops->throttle(tty); + mutex_unlock(&tty->termios_mutex); } EXPORT_SYMBOL(tty_throttle); @@ -113,13 +118,21 @@ EXPORT_SYMBOL(tty_throttle); * @tty: terminal * * Indicate that a tty may continue transmitting data down the stack. + * Takes the termios mutex to protect against parallel throttle/unthrottle + * and also to ensure the driver can consistently reference its own + * termios data at this point when implementing software flow control. + * + * Drivers should however remember that the stack can issue a throttle, + * then change flow control method, then unthrottle. */ void tty_unthrottle(struct tty_struct *tty) { + mutex_lock(&tty->termios_mutex); if (test_and_clear_bit(TTY_THROTTLED, &tty->flags) && tty->ops->unthrottle) tty->ops->unthrottle(tty); + mutex_unlock(&tty->termios_mutex); } EXPORT_SYMBOL(tty_unthrottle); @@ -613,9 +626,25 @@ static int set_termios(struct tty_struct *tty, void __user *arg, int opt) return 0; } +static void copy_termios(struct tty_struct *tty, struct ktermios *kterm) +{ + mutex_lock(&tty->termios_mutex); + memcpy(kterm, tty->termios, sizeof(struct ktermios)); + mutex_unlock(&tty->termios_mutex); +} + +static void copy_termios_locked(struct tty_struct *tty, struct ktermios *kterm) +{ + mutex_lock(&tty->termios_mutex); + memcpy(kterm, tty->termios_locked, sizeof(struct ktermios)); + mutex_unlock(&tty->termios_mutex); +} + static int get_termio(struct tty_struct *tty, struct termio __user *termio) { - if (kernel_termios_to_user_termio(termio, tty->termios)) + struct ktermios kterm; + copy_termios(tty, &kterm); + if (kernel_termios_to_user_termio(termio, &kterm)) return -EFAULT; return 0; } @@ -917,6 +946,8 @@ int tty_mode_ioctl(struct tty_struct *tty, struct file *file, struct tty_struct *real_tty; void __user *p = (void __user *)arg; int ret = 0; + struct ktermios kterm; + struct termiox ktermx; if (tty->driver->type == TTY_DRIVER_TYPE_PTY && tty->driver->subtype == PTY_TYPE_MASTER) @@ -952,23 +983,20 @@ int tty_mode_ioctl(struct tty_struct *tty, struct file *file, return set_termios(real_tty, p, TERMIOS_OLD); #ifndef TCGETS2 case TCGETS: - mutex_lock(&real_tty->termios_mutex); - if (kernel_termios_to_user_termios((struct termios __user *)arg, real_tty->termios)) + copy_termios(real_tty, &kterm); + if (kernel_termios_to_user_termios((struct termios __user *)arg, &kterm)) ret = -EFAULT; - mutex_unlock(&real_tty->termios_mutex); return ret; #else case TCGETS: - mutex_lock(&real_tty->termios_mutex); - if (kernel_termios_to_user_termios_1((struct termios __user *)arg, real_tty->termios)) + copy_termios(real_tty, &kterm); + if (kernel_termios_to_user_termios_1((struct termios __user *)arg, &kterm)) ret = -EFAULT; - mutex_unlock(&real_tty->termios_mutex); return ret; case TCGETS2: - mutex_lock(&real_tty->termios_mutex); - if (kernel_termios_to_user_termios((struct termios2 __user *)arg, real_tty->termios)) + copy_termios(real_tty, &kterm); + if (kernel_termios_to_user_termios((struct termios2 __user *)arg, &kterm)) ret = -EFAULT; - mutex_unlock(&real_tty->termios_mutex); return ret; case TCSETSF2: return set_termios(real_tty, p, TERMIOS_FLUSH | TERMIOS_WAIT); @@ -987,34 +1015,36 @@ int tty_mode_ioctl(struct tty_struct *tty, struct file *file, return set_termios(real_tty, p, TERMIOS_TERMIO); #ifndef TCGETS2 case TIOCGLCKTRMIOS: - mutex_lock(&real_tty->termios_mutex); - if (kernel_termios_to_user_termios((struct termios __user *)arg, real_tty->termios_locked)) + copy_termios_locked(real_tty, &kterm); + if (kernel_termios_to_user_termios((struct termios __user *)arg, &kterm)) ret = -EFAULT; - mutex_unlock(&real_tty->termios_mutex); return ret; case TIOCSLCKTRMIOS: if (!capable(CAP_SYS_ADMIN)) return -EPERM; - mutex_lock(&real_tty->termios_mutex); - if (user_termios_to_kernel_termios(real_tty->termios_locked, + copy_termios_locked(real_tty, &kterm); + if (user_termios_to_kernel_termios(&kterm, (struct termios __user *) arg)) - ret = -EFAULT; + return -EFAULT; + mutex_lock(&real_tty->termios_mutex); + memcpy(real_tty->termios_locked, &kterm, sizeof(struct ktermios)); mutex_unlock(&real_tty->termios_mutex); - return ret; + return 0; #else case TIOCGLCKTRMIOS: - mutex_lock(&real_tty->termios_mutex); - if (kernel_termios_to_user_termios_1((struct termios __user *)arg, real_tty->termios_locked)) + copy_termios_locked(real_tty, &kterm); + if (kernel_termios_to_user_termios_1((struct termios __user *)arg, &kterm)) ret = -EFAULT; - mutex_unlock(&real_tty->termios_mutex); return ret; case TIOCSLCKTRMIOS: if (!capable(CAP_SYS_ADMIN)) - ret = -EPERM; - mutex_lock(&real_tty->termios_mutex); - if (user_termios_to_kernel_termios_1(real_tty->termios_locked, + return -EPERM; + copy_termios_locked(real_tty, &kterm); + if (user_termios_to_kernel_termios_1(&kterm, (struct termios __user *) arg)) - ret = -EFAULT; + return -EFAULT; + mutex_lock(&real_tty->termios_mutex); + memcpy(real_tty->termios_locked, &kterm, sizeof(struct ktermios)); mutex_unlock(&real_tty->termios_mutex); return ret; #endif @@ -1023,9 +1053,10 @@ int tty_mode_ioctl(struct tty_struct *tty, struct file *file, if (real_tty->termiox == NULL) return -EINVAL; mutex_lock(&real_tty->termios_mutex); - if (copy_to_user(p, real_tty->termiox, sizeof(struct termiox))) - ret = -EFAULT; + memcpy(&ktermx, real_tty->termiox, sizeof(struct termiox)); mutex_unlock(&real_tty->termios_mutex); + if (copy_to_user(p, &ktermx, sizeof(struct termiox))) + ret = -EFAULT; return ret; case TCSETX: return set_termiox(real_tty, p, 0); @@ -1035,10 +1066,9 @@ int tty_mode_ioctl(struct tty_struct *tty, struct file *file, return set_termiox(real_tty, p, TERMIOS_FLUSH); #endif case TIOCGSOFTCAR: - mutex_lock(&real_tty->termios_mutex); - ret = put_user(C_CLOCAL(real_tty) ? 1 : 0, + copy_termios(real_tty, &kterm); + ret = put_user((kterm.c_cflag & CLOCAL) ? 1 : 0, (int __user *)arg); - mutex_unlock(&real_tty->termios_mutex); return ret; case TIOCSSOFTCAR: if (get_user(arg, (unsigned int __user *) arg)) |