diff options
Diffstat (limited to 'drivers/char/tty_ioctl.c')
| -rw-r--r-- | drivers/char/tty_ioctl.c | 59 |
1 files changed, 57 insertions, 2 deletions
diff --git a/drivers/char/tty_ioctl.c b/drivers/char/tty_ioctl.c index f19cf9d7792d..4ad47d321bd4 100644 --- a/drivers/char/tty_ioctl.c +++ b/drivers/char/tty_ioctl.c @@ -36,6 +36,18 @@ #define TERMIOS_WAIT 2 #define TERMIOS_TERMIO 4 + +/** + * tty_wait_until_sent - wait for I/O to finish + * @tty: tty we are waiting for + * @timeout: how long we will wait + * + * Wait for characters pending in a tty driver to hit the wire, or + * for a timeout to occur (eg due to flow control) + * + * Locking: none + */ + void tty_wait_until_sent(struct tty_struct * tty, long timeout) { DECLARE_WAITQUEUE(wait, current); @@ -94,6 +106,18 @@ static void unset_locked_termios(struct termios *termios, old->c_cc[i] : termios->c_cc[i]; } +/** + * change_termios - update termios values + * @tty: tty to update + * @new_termios: desired new value + * + * Perform updates to the termios values set on this terminal. There + * is a bit of layering violation here with n_tty in terms of the + * internal knowledge of this function. + * + * Locking: termios_sem + */ + static void change_termios(struct tty_struct * tty, struct termios * new_termios) { int canon_change; @@ -155,6 +179,19 @@ static void change_termios(struct tty_struct * tty, struct termios * new_termios up(&tty->termios_sem); } +/** + * set_termios - set termios values for a tty + * @tty: terminal device + * @arg: user data + * @opt: option information + * + * Helper function to prepare termios data and run neccessary other + * functions before using change_termios to do the actual changes. + * + * Locking: + * Called functions take ldisc and termios_sem locks + */ + static int set_termios(struct tty_struct * tty, void __user *arg, int opt) { struct termios tmp_termios; @@ -284,6 +321,17 @@ static void set_sgflags(struct termios * termios, int flags) } } +/** + * set_sgttyb - set legacy terminal values + * @tty: tty structure + * @sgttyb: pointer to old style terminal structure + * + * Updates a terminal from the legacy BSD style terminal information + * structure. + * + * Locking: termios_sem + */ + static int set_sgttyb(struct tty_struct * tty, struct sgttyb __user * sgttyb) { int retval; @@ -369,9 +417,16 @@ static int set_ltchars(struct tty_struct * tty, struct ltchars __user * ltchars) } #endif -/* - * Send a high priority character to the tty. +/** + * send_prio_char - send priority character + * + * Send a high priority character to the tty even if stopped + * + * Locking: none + * + * FIXME: overlapping calls with start/stop tty lose state of tty */ + static void send_prio_char(struct tty_struct *tty, char ch) { int was_stopped = tty->stopped; |