diff options
Diffstat (limited to 'drivers/char/tty_ioctl.c')
-rw-r--r-- | drivers/char/tty_ioctl.c | 126 |
1 files changed, 102 insertions, 24 deletions
diff --git a/drivers/char/tty_ioctl.c b/drivers/char/tty_ioctl.c index f95a80b2265..b1a757a5ee2 100644 --- a/drivers/char/tty_ioctl.c +++ b/drivers/char/tty_ioctl.c @@ -21,6 +21,7 @@ #include <linux/module.h> #include <linux/bitops.h> #include <linux/mutex.h> +#include <linux/smp_lock.h> #include <asm/io.h> #include <asm/uaccess.h> @@ -39,6 +40,50 @@ #define TERMIOS_OLD 8 +int tty_chars_in_buffer(struct tty_struct *tty) +{ + if (tty->ops->chars_in_buffer) + return tty->ops->chars_in_buffer(tty); + else + return 0; +} + +EXPORT_SYMBOL(tty_chars_in_buffer); + +int tty_write_room(struct tty_struct *tty) +{ + if (tty->ops->write_room) + return tty->ops->write_room(tty); + return 2048; +} + +EXPORT_SYMBOL(tty_write_room); + +void tty_driver_flush_buffer(struct tty_struct *tty) +{ + if (tty->ops->flush_buffer) + tty->ops->flush_buffer(tty); +} + +EXPORT_SYMBOL(tty_driver_flush_buffer); + +void tty_throttle(struct tty_struct *tty) +{ + /* 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); +} +EXPORT_SYMBOL(tty_throttle); + +void tty_unthrottle(struct tty_struct *tty) +{ + if (test_and_clear_bit(TTY_THROTTLED, &tty->flags) && + tty->ops->unthrottle) + tty->ops->unthrottle(tty); +} +EXPORT_SYMBOL(tty_unthrottle); + /** * tty_wait_until_sent - wait for I/O to finish * @tty: tty we are waiting for @@ -57,15 +102,13 @@ void tty_wait_until_sent(struct tty_struct *tty, long timeout) printk(KERN_DEBUG "%s wait until sent...\n", tty_name(tty, buf)); #endif - if (!tty->driver->chars_in_buffer) - return; if (!timeout) timeout = MAX_SCHEDULE_TIMEOUT; if (wait_event_interruptible_timeout(tty->write_wait, - !tty->driver->chars_in_buffer(tty), timeout) < 0) - return; - if (tty->driver->wait_until_sent) - tty->driver->wait_until_sent(tty, timeout); + !tty_chars_in_buffer(tty), timeout) >= 0) { + if (tty->ops->wait_until_sent) + tty->ops->wait_until_sent(tty, timeout); + } } EXPORT_SYMBOL(tty_wait_until_sent); @@ -393,8 +436,9 @@ EXPORT_SYMBOL(tty_termios_hw_change); static void change_termios(struct tty_struct *tty, struct ktermios *new_termios) { int canon_change; - struct ktermios old_termios = *tty->termios; + struct ktermios old_termios; struct tty_ldisc *ld; + unsigned long flags; /* * Perform the actual termios internal changes under lock. @@ -404,7 +448,7 @@ static void change_termios(struct tty_struct *tty, struct ktermios *new_termios) /* FIXME: we need to decide on some locking/ordering semantics for the set_termios notification eventually */ mutex_lock(&tty->termios_mutex); - + old_termios = *tty->termios; *tty->termios = *new_termios; unset_locked_termios(tty->termios, &old_termios, tty->termios_locked); canon_change = (old_termios.c_lflag ^ tty->termios->c_lflag) & ICANON; @@ -429,17 +473,19 @@ static void change_termios(struct tty_struct *tty, struct ktermios *new_termios) STOP_CHAR(tty) == '\023' && START_CHAR(tty) == '\021'); if (old_flow != new_flow) { + spin_lock_irqsave(&tty->ctrl_lock, flags); tty->ctrl_status &= ~(TIOCPKT_DOSTOP | TIOCPKT_NOSTOP); if (new_flow) tty->ctrl_status |= TIOCPKT_DOSTOP; else tty->ctrl_status |= TIOCPKT_NOSTOP; + spin_unlock_irqrestore(&tty->ctrl_lock, flags); wake_up_interruptible(&tty->link->read_wait); } } - if (tty->driver->set_termios) - (*tty->driver->set_termios)(tty, &old_termios); + if (tty->ops->set_termios) + (*tty->ops->set_termios)(tty, &old_termios); else tty_termios_copy_hw(tty->termios, &old_termios); @@ -474,7 +520,9 @@ static int set_termios(struct tty_struct *tty, void __user *arg, int opt) if (retval) return retval; + mutex_lock(&tty->termios_mutex); memcpy(&tmp_termios, tty->termios, sizeof(struct ktermios)); + mutex_unlock(&tty->termios_mutex); if (opt & TERMIOS_TERMIO) { if (user_termio_to_kernel_termios(&tmp_termios, @@ -660,12 +708,14 @@ static int get_tchars(struct tty_struct *tty, struct tchars __user *tchars) { struct tchars tmp; + mutex_lock(&tty->termios_mutex); tmp.t_intrc = tty->termios->c_cc[VINTR]; tmp.t_quitc = tty->termios->c_cc[VQUIT]; tmp.t_startc = tty->termios->c_cc[VSTART]; tmp.t_stopc = tty->termios->c_cc[VSTOP]; tmp.t_eofc = tty->termios->c_cc[VEOF]; tmp.t_brkc = tty->termios->c_cc[VEOL2]; /* what is brkc anyway? */ + mutex_unlock(&tty->termios_mutex); return copy_to_user(tchars, &tmp, sizeof(tmp)) ? -EFAULT : 0; } @@ -675,12 +725,14 @@ static int set_tchars(struct tty_struct *tty, struct tchars __user *tchars) if (copy_from_user(&tmp, tchars, sizeof(tmp))) return -EFAULT; + mutex_lock(&tty->termios_mutex); tty->termios->c_cc[VINTR] = tmp.t_intrc; tty->termios->c_cc[VQUIT] = tmp.t_quitc; tty->termios->c_cc[VSTART] = tmp.t_startc; tty->termios->c_cc[VSTOP] = tmp.t_stopc; tty->termios->c_cc[VEOF] = tmp.t_eofc; tty->termios->c_cc[VEOL2] = tmp.t_brkc; /* what is brkc anyway? */ + mutex_unlock(&tty->termios_mutex); return 0; } #endif @@ -690,6 +742,7 @@ static int get_ltchars(struct tty_struct *tty, struct ltchars __user *ltchars) { struct ltchars tmp; + mutex_lock(&tty->termios_mutex); tmp.t_suspc = tty->termios->c_cc[VSUSP]; /* what is dsuspc anyway? */ tmp.t_dsuspc = tty->termios->c_cc[VSUSP]; @@ -698,6 +751,7 @@ static int get_ltchars(struct tty_struct *tty, struct ltchars __user *ltchars) tmp.t_flushc = tty->termios->c_cc[VEOL2]; tmp.t_werasc = tty->termios->c_cc[VWERASE]; tmp.t_lnextc = tty->termios->c_cc[VLNEXT]; + mutex_unlock(&tty->termios_mutex); return copy_to_user(ltchars, &tmp, sizeof(tmp)) ? -EFAULT : 0; } @@ -708,6 +762,7 @@ static int set_ltchars(struct tty_struct *tty, struct ltchars __user *ltchars) if (copy_from_user(&tmp, ltchars, sizeof(tmp))) return -EFAULT; + mutex_lock(&tty->termios_mutex); tty->termios->c_cc[VSUSP] = tmp.t_suspc; /* what is dsuspc anyway? */ tty->termios->c_cc[VEOL2] = tmp.t_dsuspc; @@ -716,6 +771,7 @@ static int set_ltchars(struct tty_struct *tty, struct ltchars __user *ltchars) tty->termios->c_cc[VEOL2] = tmp.t_flushc; tty->termios->c_cc[VWERASE] = tmp.t_werasc; tty->termios->c_cc[VLNEXT] = tmp.t_lnextc; + mutex_unlock(&tty->termios_mutex); return 0; } #endif @@ -732,8 +788,8 @@ static int send_prio_char(struct tty_struct *tty, char ch) { int was_stopped = tty->stopped; - if (tty->driver->send_xchar) { - tty->driver->send_xchar(tty, ch); + if (tty->ops->send_xchar) { + tty->ops->send_xchar(tty, ch); return 0; } @@ -742,7 +798,7 @@ static int send_prio_char(struct tty_struct *tty, char ch) if (was_stopped) start_tty(tty); - tty->driver->write(tty, &ch, 1); + tty->ops->write(tty, &ch, 1); if (was_stopped) stop_tty(tty); tty_write_unlock(tty); @@ -750,6 +806,33 @@ static int send_prio_char(struct tty_struct *tty, char ch) } /** + * tty_change_softcar - carrier change ioctl helper + * @tty: tty to update + * @arg: enable/disable CLOCAL + * + * Perform a change to the CLOCAL state and call into the driver + * layer to make it visible. All done with the termios mutex + */ + +static int tty_change_softcar(struct tty_struct *tty, int arg) +{ + int ret = 0; + int bit = arg ? CLOCAL : 0; + struct ktermios old; + + mutex_lock(&tty->termios_mutex); + old = *tty->termios; + tty->termios->c_cflag &= ~CLOCAL; + tty->termios->c_cflag |= bit; + if (tty->ops->set_termios) + tty->ops->set_termios(tty, &old); + if ((tty->termios->c_cflag & CLOCAL) != bit) + ret = -EINVAL; + mutex_unlock(&tty->termios_mutex); + return ret; +} + +/** * tty_mode_ioctl - mode related ioctls * @tty: tty for the ioctl * @file: file pointer for the tty @@ -859,12 +942,7 @@ int tty_mode_ioctl(struct tty_struct *tty, struct file *file, case TIOCSSOFTCAR: if (get_user(arg, (unsigned int __user *) arg)) return -EFAULT; - mutex_lock(&tty->termios_mutex); - tty->termios->c_cflag = - ((tty->termios->c_cflag & ~CLOCAL) | - (arg ? CLOCAL : 0)); - mutex_unlock(&tty->termios_mutex); - return 0; + return tty_change_softcar(tty, arg); default: return -ENOIOCTLCMD; } @@ -889,8 +967,7 @@ int tty_perform_flush(struct tty_struct *tty, unsigned long arg) ld->flush_buffer(tty); /* fall through */ case TCOFLUSH: - if (tty->driver->flush_buffer) - tty->driver->flush_buffer(tty); + tty_driver_flush_buffer(tty); break; default: tty_ldisc_deref(ld); @@ -905,6 +982,7 @@ int n_tty_ioctl(struct tty_struct *tty, struct file *file, unsigned int cmd, unsigned long arg) { struct tty_struct *real_tty; + unsigned long flags; int retval; if (tty->driver->type == TTY_DRIVER_TYPE_PTY && @@ -946,9 +1024,7 @@ int n_tty_ioctl(struct tty_struct *tty, struct file *file, case TCFLSH: return tty_perform_flush(tty, arg); case TIOCOUTQ: - return put_user(tty->driver->chars_in_buffer ? - tty->driver->chars_in_buffer(tty) : 0, - (int __user *) arg); + return put_user(tty_chars_in_buffer(tty), (int __user *) arg); case TIOCINQ: retval = tty->read_cnt; if (L_ICANON(tty)) @@ -963,6 +1039,7 @@ int n_tty_ioctl(struct tty_struct *tty, struct file *file, return -ENOTTY; if (get_user(pktmode, (int __user *) arg)) return -EFAULT; + spin_lock_irqsave(&tty->ctrl_lock, flags); if (pktmode) { if (!tty->packet) { tty->packet = 1; @@ -970,6 +1047,7 @@ int n_tty_ioctl(struct tty_struct *tty, struct file *file, } } else tty->packet = 0; + spin_unlock_irqrestore(&tty->ctrl_lock, flags); return 0; } default: |