diff options
Diffstat (limited to 'drivers/char/tty_ioctl.c')
| -rw-r--r-- | drivers/char/tty_ioctl.c | 551 |
1 files changed, 551 insertions, 0 deletions
diff --git a/drivers/char/tty_ioctl.c b/drivers/char/tty_ioctl.c new file mode 100644 index 00000000000..58597993954 --- /dev/null +++ b/drivers/char/tty_ioctl.c @@ -0,0 +1,551 @@ +/* + * linux/drivers/char/tty_ioctl.c + * + * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds + * + * Modified by Fred N. van Kempen, 01/29/93, to add line disciplines + * which can be dynamically activated and de-activated by the line + * discipline handling modules (like SLIP). + */ + +#include <linux/types.h> +#include <linux/termios.h> +#include <linux/errno.h> +#include <linux/sched.h> +#include <linux/kernel.h> +#include <linux/major.h> +#include <linux/tty.h> +#include <linux/fcntl.h> +#include <linux/string.h> +#include <linux/mm.h> +#include <linux/module.h> +#include <linux/bitops.h> + +#include <asm/io.h> +#include <asm/uaccess.h> +#include <asm/system.h> + +#undef TTY_DEBUG_WAIT_UNTIL_SENT + +#undef DEBUG + +/* + * Internal flag options for termios setting behavior + */ +#define TERMIOS_FLUSH 1 +#define TERMIOS_WAIT 2 +#define TERMIOS_TERMIO 4 + +void tty_wait_until_sent(struct tty_struct * tty, long timeout) +{ + DECLARE_WAITQUEUE(wait, current); + +#ifdef TTY_DEBUG_WAIT_UNTIL_SENT + char buf[64]; + + printk(KERN_DEBUG "%s wait until sent...\n", tty_name(tty, buf)); +#endif + if (!tty->driver->chars_in_buffer) + return; + add_wait_queue(&tty->write_wait, &wait); + if (!timeout) + timeout = MAX_SCHEDULE_TIMEOUT; + do { +#ifdef TTY_DEBUG_WAIT_UNTIL_SENT + printk(KERN_DEBUG "waiting %s...(%d)\n", tty_name(tty, buf), + tty->driver->chars_in_buffer(tty)); +#endif + set_current_state(TASK_INTERRUPTIBLE); + if (signal_pending(current)) + goto stop_waiting; + if (!tty->driver->chars_in_buffer(tty)) + break; + timeout = schedule_timeout(timeout); + } while (timeout); + if (tty->driver->wait_until_sent) + tty->driver->wait_until_sent(tty, timeout); +stop_waiting: + set_current_state(TASK_RUNNING); + remove_wait_queue(&tty->write_wait, &wait); +} + +EXPORT_SYMBOL(tty_wait_until_sent); + +static void unset_locked_termios(struct termios *termios, + struct termios *old, + struct termios *locked) +{ + int i; + +#define NOSET_MASK(x,y,z) (x = ((x) & ~(z)) | ((y) & (z))) + + if (!locked) { + printk(KERN_WARNING "Warning?!? termios_locked is NULL.\n"); + return; + } + + NOSET_MASK(termios->c_iflag, old->c_iflag, locked->c_iflag); + NOSET_MASK(termios->c_oflag, old->c_oflag, locked->c_oflag); + NOSET_MASK(termios->c_cflag, old->c_cflag, locked->c_cflag); + NOSET_MASK(termios->c_lflag, old->c_lflag, locked->c_lflag); + termios->c_line = locked->c_line ? old->c_line : termios->c_line; + for (i=0; i < NCCS; i++) + termios->c_cc[i] = locked->c_cc[i] ? + old->c_cc[i] : termios->c_cc[i]; +} + +static void change_termios(struct tty_struct * tty, struct termios * new_termios) +{ + int canon_change; + struct termios old_termios = *tty->termios; + struct tty_ldisc *ld; + + /* + * Perform the actual termios internal changes under lock. + */ + + + /* FIXME: we need to decide on some locking/ordering semantics + for the set_termios notification eventually */ + down(&tty->termios_sem); + + *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; + } + + + 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) { + int old_flow = ((old_termios.c_iflag & IXON) && + (old_termios.c_cc[VSTOP] == '\023') && + (old_termios.c_cc[VSTART] == '\021')); + int new_flow = (I_IXON(tty) && + STOP_CHAR(tty) == '\023' && + START_CHAR(tty) == '\021'); + if (old_flow != new_flow) { + tty->ctrl_status &= ~(TIOCPKT_DOSTOP | TIOCPKT_NOSTOP); + if (new_flow) + tty->ctrl_status |= TIOCPKT_DOSTOP; + else + tty->ctrl_status |= TIOCPKT_NOSTOP; + wake_up_interruptible(&tty->link->read_wait); + } + } + + if (tty->driver->set_termios) + (*tty->driver->set_termios)(tty, &old_termios); + + ld = tty_ldisc_ref(tty); + if (ld != NULL) { + if (ld->set_termios) + (ld->set_termios)(tty, &old_termios); + tty_ldisc_deref(ld); + } + up(&tty->termios_sem); +} + +static int set_termios(struct tty_struct * tty, void __user *arg, int opt) +{ + struct termios tmp_termios; + struct tty_ldisc *ld; + int retval = tty_check_change(tty); + + if (retval) + return retval; + + if (opt & TERMIOS_TERMIO) { + memcpy(&tmp_termios, tty->termios, sizeof(struct termios)); + if (user_termio_to_kernel_termios(&tmp_termios, + (struct termio __user *)arg)) + return -EFAULT; + } else { + if (user_termios_to_kernel_termios(&tmp_termios, + (struct termios __user *)arg)) + return -EFAULT; + } + + ld = tty_ldisc_ref(tty); + + if (ld != NULL) { + if ((opt & TERMIOS_FLUSH) && ld->flush_buffer) + ld->flush_buffer(tty); + tty_ldisc_deref(ld); + } + + if (opt & TERMIOS_WAIT) { + tty_wait_until_sent(tty, 0); + if (signal_pending(current)) + return -EINTR; + } + + change_termios(tty, &tmp_termios); + return 0; +} + +static int get_termio(struct tty_struct * tty, struct termio __user * termio) +{ + if (kernel_termios_to_user_termio(termio, tty->termios)) + return -EFAULT; + return 0; +} + +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 +/* + * These are deprecated, but there is limited support.. + * + * The "sg_flags" translation is a joke.. + */ +static int get_sgflags(struct tty_struct * tty) +{ + int flags = 0; + + if (!(tty->termios->c_lflag & ICANON)) { + if (tty->termios->c_lflag & ISIG) + flags |= 0x02; /* cbreak */ + else + flags |= 0x20; /* raw */ + } + if (tty->termios->c_lflag & ECHO) + flags |= 0x08; /* echo */ + if (tty->termios->c_oflag & OPOST) + if (tty->termios->c_oflag & ONLCR) + flags |= 0x10; /* crmod */ + return flags; +} + +static int get_sgttyb(struct tty_struct * tty, struct sgttyb __user * sgttyb) +{ + struct sgttyb tmp; + + down(&tty->termios_sem); + tmp.sg_ispeed = 0; + tmp.sg_ospeed = 0; + tmp.sg_erase = tty->termios->c_cc[VERASE]; + tmp.sg_kill = tty->termios->c_cc[VKILL]; + tmp.sg_flags = get_sgflags(tty); + up(&tty->termios_sem); + + return copy_to_user(sgttyb, &tmp, sizeof(tmp)) ? -EFAULT : 0; +} + +static void set_sgflags(struct termios * termios, int flags) +{ + termios->c_iflag = ICRNL | IXON; + termios->c_oflag = 0; + termios->c_lflag = ISIG | ICANON; + if (flags & 0x02) { /* cbreak */ + termios->c_iflag = 0; + termios->c_lflag &= ~ICANON; + } + if (flags & 0x08) { /* echo */ + termios->c_lflag |= ECHO | ECHOE | ECHOK | + ECHOCTL | ECHOKE | IEXTEN; + } + if (flags & 0x10) { /* crmod */ + termios->c_oflag |= OPOST | ONLCR; + } + if (flags & 0x20) { /* raw */ + termios->c_iflag = 0; + termios->c_lflag &= ~(ISIG | ICANON); + } + if (!(termios->c_lflag & ICANON)) { + termios->c_cc[VMIN] = 1; + termios->c_cc[VTIME] = 0; + } +} + +static int set_sgttyb(struct tty_struct * tty, struct sgttyb __user * sgttyb) +{ + int retval; + struct sgttyb tmp; + struct termios termios; + + retval = tty_check_change(tty); + if (retval) + return retval; + + if (copy_from_user(&tmp, sgttyb, sizeof(tmp))) + return -EFAULT; + + down(&tty->termios_sem); + termios = *tty->termios; + termios.c_cc[VERASE] = tmp.sg_erase; + termios.c_cc[VKILL] = tmp.sg_kill; + set_sgflags(&termios, tmp.sg_flags); + up(&tty->termios_sem); + change_termios(tty, &termios); + return 0; +} +#endif + +#ifdef TIOCGETC +static int get_tchars(struct tty_struct * tty, struct tchars __user * tchars) +{ + struct tchars tmp; + + 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? */ + return copy_to_user(tchars, &tmp, sizeof(tmp)) ? -EFAULT : 0; +} + +static int set_tchars(struct tty_struct * tty, struct tchars __user * tchars) +{ + struct tchars tmp; + + if (copy_from_user(&tmp, tchars, sizeof(tmp))) + return -EFAULT; + 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? */ + return 0; +} +#endif + +#ifdef TIOCGLTC +static int get_ltchars(struct tty_struct * tty, struct ltchars __user * ltchars) +{ + struct ltchars tmp; + + tmp.t_suspc = tty->termios->c_cc[VSUSP]; + tmp.t_dsuspc = tty->termios->c_cc[VSUSP]; /* what is dsuspc anyway? */ + tmp.t_rprntc = tty->termios->c_cc[VREPRINT]; + tmp.t_flushc = tty->termios->c_cc[VEOL2]; /* what is flushc anyway? */ + tmp.t_werasc = tty->termios->c_cc[VWERASE]; + tmp.t_lnextc = tty->termios->c_cc[VLNEXT]; + return copy_to_user(ltchars, &tmp, sizeof(tmp)) ? -EFAULT : 0; +} + +static int set_ltchars(struct tty_struct * tty, struct ltchars __user * ltchars) +{ + struct ltchars tmp; + + if (copy_from_user(&tmp, ltchars, sizeof(tmp))) + return -EFAULT; + + tty->termios->c_cc[VSUSP] = tmp.t_suspc; + tty->termios->c_cc[VEOL2] = tmp.t_dsuspc; /* what is dsuspc anyway? */ + tty->termios->c_cc[VREPRINT] = tmp.t_rprntc; + tty->termios->c_cc[VEOL2] = tmp.t_flushc; /* what is flushc anyway? */ + tty->termios->c_cc[VWERASE] = tmp.t_werasc; + tty->termios->c_cc[VLNEXT] = tmp.t_lnextc; + return 0; +} +#endif + +/* + * Send a high priority character to the tty. + */ +static void 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); + return; + } + if (was_stopped) + start_tty(tty); + tty->driver->write(tty, &ch, 1); + if (was_stopped) + stop_tty(tty); +} + +int n_tty_ioctl(struct tty_struct * tty, struct file * file, + unsigned int cmd, unsigned long arg) +{ + struct tty_struct * real_tty; + void __user *p = (void __user *)arg; + int retval; + struct tty_ldisc *ld; + + if (tty->driver->type == TTY_DRIVER_TYPE_PTY && + tty->driver->subtype == PTY_TYPE_MASTER) + real_tty = tty->link; + else + real_tty = tty; + + switch (cmd) { +#ifdef TIOCGETP + case TIOCGETP: + return get_sgttyb(real_tty, (struct sgttyb __user *) arg); + case TIOCSETP: + case TIOCSETN: + return set_sgttyb(real_tty, (struct sgttyb __user *) arg); +#endif +#ifdef TIOCGETC + case TIOCGETC: + return get_tchars(real_tty, p); + case TIOCSETC: + return set_tchars(real_tty, p); +#endif +#ifdef TIOCGLTC + case TIOCGLTC: + return get_ltchars(real_tty, p); + case TIOCSLTC: + return set_ltchars(real_tty, p); +#endif + case TCGETS: + if (kernel_termios_to_user_termios((struct termios __user *)arg, real_tty->termios)) + return -EFAULT; + return 0; + case TCSETSF: + return set_termios(real_tty, p, TERMIOS_FLUSH | TERMIOS_WAIT); + case TCSETSW: + return set_termios(real_tty, p, TERMIOS_WAIT); + case TCSETS: + return set_termios(real_tty, p, 0); + case TCGETA: + return get_termio(real_tty, p); + case TCSETAF: + return set_termios(real_tty, p, TERMIOS_FLUSH | TERMIOS_WAIT | TERMIOS_TERMIO); + case TCSETAW: + return set_termios(real_tty, p, TERMIOS_WAIT | TERMIOS_TERMIO); + case TCSETA: + return set_termios(real_tty, p, TERMIOS_TERMIO); + case TCXONC: + retval = tty_check_change(tty); + if (retval) + return retval; + switch (arg) { + case TCOOFF: + if (!tty->flow_stopped) { + tty->flow_stopped = 1; + stop_tty(tty); + } + break; + case TCOON: + if (tty->flow_stopped) { + tty->flow_stopped = 0; + start_tty(tty); + } + break; + case TCIOFF: + if (STOP_CHAR(tty) != __DISABLED_CHAR) + send_prio_char(tty, STOP_CHAR(tty)); + break; + case TCION: + if (START_CHAR(tty) != __DISABLED_CHAR) + send_prio_char(tty, START_CHAR(tty)); + break; + default: + return -EINVAL; + } + return 0; + case TCFLSH: + retval = tty_check_change(tty); + if (retval) + return retval; + + ld = tty_ldisc_ref(tty); + switch (arg) { + case TCIFLUSH: + if (ld->flush_buffer) + ld->flush_buffer(tty); + break; + case TCIOFLUSH: + if (ld->flush_buffer) + ld->flush_buffer(tty); + /* fall through */ + case TCOFLUSH: + if (tty->driver->flush_buffer) + tty->driver->flush_buffer(tty); + break; + default: + tty_ldisc_deref(ld); + return -EINVAL; + } + tty_ldisc_deref(ld); + return 0; + case TIOCOUTQ: + return put_user(tty->driver->chars_in_buffer ? + tty->driver->chars_in_buffer(tty) : 0, + (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 TIOCGLCKTRMIOS: + if (kernel_termios_to_user_termios((struct termios __user *)arg, real_tty->termios_locked)) + return -EFAULT; + return 0; + + case TIOCSLCKTRMIOS: + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + if (user_termios_to_kernel_termios(real_tty->termios_locked, (struct termios __user *) arg)) + return -EFAULT; + return 0; + + case TIOCPKT: + { + int pktmode; + + if (tty->driver->type != TTY_DRIVER_TYPE_PTY || + tty->driver->subtype != PTY_TYPE_MASTER) + return -ENOTTY; + if (get_user(pktmode, (int __user *) arg)) + return -EFAULT; + if (pktmode) { + if (!tty->packet) { + tty->packet = 1; + tty->link->ctrl_status = 0; + } + } else + tty->packet = 0; + return 0; + } + case TIOCGSOFTCAR: + return put_user(C_CLOCAL(tty) ? 1 : 0, (int __user *)arg); + case TIOCSSOFTCAR: + if (get_user(arg, (unsigned int __user *) arg)) + return -EFAULT; + down(&tty->termios_sem); + tty->termios->c_cflag = + ((tty->termios->c_cflag & ~CLOCAL) | + (arg ? CLOCAL : 0)); + up(&tty->termios_sem); + return 0; + default: + return -ENOIOCTLCMD; + } +} + +EXPORT_SYMBOL(n_tty_ioctl); |