/* * 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);