tty/serial: lay the foundations for the next set of reworks

[linux-2.6-block.git] / drivers / char / tty_ioctl.c

diff --git a/drivers/char/tty_ioctl.c b/drivers/char/tty_ioctl.c
index d769e43f73fb7c7c9905e0c6f6f5e81e45bcefdc..8c4bf3e48d5b163533360f4cbf442dcd8322d714 100644 (file)
--- a/drivers/char/tty_ioctl.c
+++ b/drivers/char/tty_ioctl.c
@@ -396,7 +396,7 @@ 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;
 
@@ -408,7 +408,7 @@ 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;
@@ -480,7 +480,9 @@ 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,
@@ -666,12 +668,14 @@ 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;
 }
 
@@ -681,12 +685,14 @@ 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
@@ -696,6 +702,7 @@ 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];
@@ -704,6 +711,7 @@ 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;
 }
 
@@ -714,6 +722,7 @@ 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;
@@ -722,6 +731,7 @@ 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