diff options
Diffstat (limited to 'drivers/char/tty_io.c')
| -rw-r--r-- | drivers/char/tty_io.c | 43 |
1 files changed, 18 insertions, 25 deletions
diff --git a/drivers/char/tty_io.c b/drivers/char/tty_io.c index db15f9ba7c0b..bc84e125c6bc 100644 --- a/drivers/char/tty_io.c +++ b/drivers/char/tty_io.c @@ -1111,9 +1111,7 @@ void tty_write_message(struct tty_struct *tty, char *msg) * Locks the line discipline as required * Writes to the tty driver are serialized by the atomic_write_lock * and are then processed in chunks to the device. The line discipline - * write method will not be involked in parallel for each device - * The line discipline write method is called under the big - * kernel lock for historical reasons. New code should not rely on this. + * write method will not be invoked in parallel for each device. */ static ssize_t tty_write(struct file *file, const char __user *buf, @@ -1213,7 +1211,7 @@ static void tty_line_name(struct tty_driver *driver, int index, char *p) * be held until the 'fast-open' is also done. Will change once we * have refcounting in the driver and per driver locking */ -struct tty_struct *tty_driver_lookup_tty(struct tty_driver *driver, +static struct tty_struct *tty_driver_lookup_tty(struct tty_driver *driver, struct inode *inode, int idx) { struct tty_struct *tty; @@ -1819,8 +1817,10 @@ got_driver: /* check whether we're reopening an existing tty */ tty = tty_driver_lookup_tty(driver, inode, index); - if (IS_ERR(tty)) + if (IS_ERR(tty)) { + mutex_unlock(&tty_mutex); return PTR_ERR(tty); + } } if (tty) { @@ -2050,7 +2050,6 @@ static int tiocgwinsz(struct tty_struct *tty, struct winsize __user *arg) /** * tty_do_resize - resize event * @tty: tty being resized - * @real_tty: real tty (not the same as tty if using a pty/tty pair) * @rows: rows (character) * @cols: cols (character) * @@ -2058,41 +2057,34 @@ static int tiocgwinsz(struct tty_struct *tty, struct winsize __user *arg) * peform a terminal resize correctly */ -int tty_do_resize(struct tty_struct *tty, struct tty_struct *real_tty, - struct winsize *ws) +int tty_do_resize(struct tty_struct *tty, struct winsize *ws) { - struct pid *pgrp, *rpgrp; + struct pid *pgrp; unsigned long flags; - /* For a PTY we need to lock the tty side */ - mutex_lock(&real_tty->termios_mutex); - if (!memcmp(ws, &real_tty->winsize, sizeof(*ws))) + /* Lock the tty */ + mutex_lock(&tty->termios_mutex); + if (!memcmp(ws, &tty->winsize, sizeof(*ws))) goto done; /* Get the PID values and reference them so we can avoid holding the tty ctrl lock while sending signals */ spin_lock_irqsave(&tty->ctrl_lock, flags); pgrp = get_pid(tty->pgrp); - rpgrp = get_pid(real_tty->pgrp); spin_unlock_irqrestore(&tty->ctrl_lock, flags); if (pgrp) kill_pgrp(pgrp, SIGWINCH, 1); - if (rpgrp != pgrp && rpgrp) - kill_pgrp(rpgrp, SIGWINCH, 1); - put_pid(pgrp); - put_pid(rpgrp); tty->winsize = *ws; - real_tty->winsize = *ws; done: - mutex_unlock(&real_tty->termios_mutex); + mutex_unlock(&tty->termios_mutex); return 0; } /** * tiocswinsz - implement window size set ioctl - * @tty; tty + * @tty; tty side of tty * @arg: user buffer for result * * Copies the user idea of the window size to the kernel. Traditionally @@ -2105,17 +2097,16 @@ done: * then calls into the default method. */ -static int tiocswinsz(struct tty_struct *tty, struct tty_struct *real_tty, - struct winsize __user *arg) +static int tiocswinsz(struct tty_struct *tty, struct winsize __user *arg) { struct winsize tmp_ws; if (copy_from_user(&tmp_ws, arg, sizeof(*arg))) return -EFAULT; if (tty->ops->resize) - return tty->ops->resize(tty, real_tty, &tmp_ws); + return tty->ops->resize(tty, &tmp_ws); else - return tty_do_resize(tty, real_tty, &tmp_ws); + return tty_do_resize(tty, &tmp_ws); } /** @@ -2540,7 +2531,7 @@ long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg) case TIOCGWINSZ: return tiocgwinsz(real_tty, p); case TIOCSWINSZ: - return tiocswinsz(tty, real_tty, p); + return tiocswinsz(real_tty, p); case TIOCCONS: return real_tty != tty ? -EINVAL : tioccons(file); case FIONBIO: @@ -2785,6 +2776,8 @@ void initialize_tty_struct(struct tty_struct *tty, INIT_WORK(&tty->hangup_work, do_tty_hangup); mutex_init(&tty->atomic_read_lock); mutex_init(&tty->atomic_write_lock); + mutex_init(&tty->output_lock); + mutex_init(&tty->echo_lock); spin_lock_init(&tty->read_lock); spin_lock_init(&tty->ctrl_lock); INIT_LIST_HEAD(&tty->tty_files); |