From: Alan Cox Date: Mon, 13 Oct 2008 09:44:17 +0000 (+0100) Subject: tty: some ICANON magic is in the wrong places X-Git-Tag: firefly_0821_release~17730 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=47afa7a5a8a8fb9e60cdb6a3bd612e07c37e9d90;p=firefly-linux-kernel-4.4.55.git tty: some ICANON magic is in the wrong places Move the set up on ldisc change into the ldisc Move the INQ/OUTQ cases into the driver not in shared ioctl code where it gives bogus answers for other ldisc values Signed-off-by: Alan Cox Signed-off-by: Linus Torvalds --- diff --git a/drivers/bluetooth/hci_ldisc.c b/drivers/bluetooth/hci_ldisc.c index 8dfcf77cb717..4426bb552bd9 100644 --- a/drivers/bluetooth/hci_ldisc.c +++ b/drivers/bluetooth/hci_ldisc.c @@ -484,7 +484,7 @@ static int hci_uart_tty_ioctl(struct tty_struct *tty, struct file * file, return -EUNATCH; default: - err = n_tty_ioctl(tty, file, cmd, arg); + err = n_tty_ioctl_helper(tty, file, cmd, arg); break; }; diff --git a/drivers/char/n_hdlc.c b/drivers/char/n_hdlc.c index 69ec6399c714..bacb3e2872ae 100644 --- a/drivers/char/n_hdlc.c +++ b/drivers/char/n_hdlc.c @@ -764,7 +764,7 @@ static int n_hdlc_tty_ioctl(struct tty_struct *tty, struct file *file, break; default: - error = n_tty_ioctl (tty, file, cmd, arg); + error = n_tty_ioctl_helper(tty, file, cmd, arg); break; } return error; diff --git a/drivers/char/n_tty.c b/drivers/char/n_tty.c index 708c2b1dbe51..b4f5dccad2a6 100644 --- a/drivers/char/n_tty.c +++ b/drivers/char/n_tty.c @@ -1011,8 +1011,20 @@ int is_ignored(int sig) static void n_tty_set_termios(struct tty_struct *tty, struct ktermios *old) { - if (!tty) - return; + int canon_change = 1; + BUG_ON(!tty); + + if (old) + canon_change = (old->c_lflag ^ tty->termios->c_lflag) & ICANON; + if (canon_change) { + memset(&tty->read_flags, 0, sizeof tty->read_flags); + tty->canon_head = tty->read_tail; + tty->canon_data = 0; + tty->erasing = 0; + } + + if (canon_change && !L_ICANON(tty) && tty->read_cnt) + wake_up_interruptible(&tty->read_wait); tty->icanon = (L_ICANON(tty) != 0); if (test_bit(TTY_HW_COOK_IN, &tty->flags)) { @@ -1573,6 +1585,43 @@ static unsigned int normal_poll(struct tty_struct *tty, struct file *file, return mask; } +static unsigned long inq_canon(struct tty_struct *tty) +{ + int nr, head, tail; + + if (!tty->canon_data || !tty->read_buf) + return 0; + head = tty->canon_head; + tail = tty->read_tail; + nr = (head - tail) & (N_TTY_BUF_SIZE-1); + /* Skip EOF-chars.. */ + while (head != tail) { + if (test_bit(tail, tty->read_flags) && + tty->read_buf[tail] == __DISABLED_CHAR) + nr--; + tail = (tail+1) & (N_TTY_BUF_SIZE-1); + } + return nr; +} + +static int n_tty_ioctl(struct tty_struct *tty, struct file *file, + unsigned int cmd, unsigned long arg) +{ + int retval; + + switch (cmd) { + case TIOCOUTQ: + return put_user(tty_chars_in_buffer(tty), (int __user *) arg); + case TIOCINQ: + retval = tty->read_cnt; + if (L_ICANON(tty)) + retval = inq_canon(tty); + return put_user(retval, (unsigned int __user *) arg); + default: + return n_tty_ioctl_helper(tty, file, cmd, arg); + } +} + struct tty_ldisc_ops tty_ldisc_N_TTY = { .magic = TTY_LDISC_MAGIC, .name = "n_tty", diff --git a/drivers/char/tty_ioctl.c b/drivers/char/tty_ioctl.c index 14cc19c344cc..a408c8e487ec 100644 --- a/drivers/char/tty_ioctl.c +++ b/drivers/char/tty_ioctl.c @@ -489,7 +489,6 @@ 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; struct tty_ldisc *ld; unsigned long flags; @@ -505,18 +504,6 @@ static void change_termios(struct tty_struct *tty, struct ktermios *new_termios) 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; - if (canon_change) { - memset(&tty->read_flags, 0, sizeof tty->read_flags); - tty->canon_head = tty->read_tail; - tty->canon_data = 0; - tty->erasing = 0; - } - - /* This bit should be in the ldisc code */ - if (canon_change && !L_ICANON(tty) && tty->read_cnt) - /* Get characters left over from canonical mode. */ - wake_up_interruptible(&tty->read_wait); /* See if packet mode change of state. */ if (tty->link && tty->link->packet) { @@ -677,24 +664,6 @@ static int set_termiox(struct tty_struct *tty, void __user *arg, int opt) #endif -static unsigned long inq_canon(struct tty_struct *tty) -{ - int nr, head, tail; - - if (!tty->canon_data || !tty->read_buf) - return 0; - head = tty->canon_head; - tail = tty->read_tail; - nr = (head - tail) & (N_TTY_BUF_SIZE-1); - /* Skip EOF-chars.. */ - while (head != tail) { - if (test_bit(tail, tty->read_flags) && - tty->read_buf[tail] == __DISABLED_CHAR) - nr--; - tail = (tail+1) & (N_TTY_BUF_SIZE-1); - } - return nr; -} #ifdef TIOCGETP /* @@ -1110,7 +1079,7 @@ int tty_perform_flush(struct tty_struct *tty, unsigned long arg) } EXPORT_SYMBOL_GPL(tty_perform_flush); -int n_tty_ioctl(struct tty_struct *tty, struct file *file, +int n_tty_ioctl_helper(struct tty_struct *tty, struct file *file, unsigned int cmd, unsigned long arg) { unsigned long flags; @@ -1148,13 +1117,6 @@ int n_tty_ioctl(struct tty_struct *tty, struct file *file, return 0; case TCFLSH: return tty_perform_flush(tty, arg); - case TIOCOUTQ: - return put_user(tty_chars_in_buffer(tty), (int __user *) arg); - case TIOCINQ: - retval = tty->read_cnt; - if (L_ICANON(tty)) - retval = inq_canon(tty); - return put_user(retval, (unsigned int __user *) arg); case TIOCPKT: { int pktmode; @@ -1180,4 +1142,4 @@ int n_tty_ioctl(struct tty_struct *tty, struct file *file, return tty_mode_ioctl(tty, file, cmd, arg); } } -EXPORT_SYMBOL(n_tty_ioctl); +EXPORT_SYMBOL(n_tty_ioctl_helper); diff --git a/include/linux/tty.h b/include/linux/tty.h index 3c7c75794a4a..3b8121d4e36f 100644 --- a/include/linux/tty.h +++ b/include/linux/tty.h @@ -466,7 +466,7 @@ static inline void tty_audit_push_task(struct task_struct *tsk, #endif /* tty_ioctl.c */ -extern int n_tty_ioctl(struct tty_struct *tty, struct file *file, +extern int n_tty_ioctl_helper(struct tty_struct *tty, struct file *file, unsigned int cmd, unsigned long arg); /* serial.c */