kernel/chr_drv/tty_ioctl.c - pub/scm/linux/kernel/git/nico/archive - Git at Google

 /*
  *  linux/kernel/chr_drv/tty_ioctl.c
  *
  *  (C) 1991  Linus Torvalds
  */

 #include <errno.h>
 #include <termios.h>
 #include <sys/types.h>

 #include <linux/sched.h>
 #include <linux/kernel.h>
 #include <linux/tty.h>

 #include <asm/io.h>
 #include <asm/segment.h>
 #include <asm/system.h>

 extern int session_of_pgrp(int pgrp);
 extern int do_screendump(int arg);
 extern int kill_pg(int pgrp, int sig, int priv);
 extern int vt_ioctl(struct tty_struct *tty, int dev, int cmd, int arg);

 static void flush(struct tty_queue * queue)
 {
 	if (queue) {
 		cli();
 		queue->head = queue->tail;
 		sti();
 		wake_up(&queue->proc_list);
 	}
 }

 void flush_input(struct tty_struct * tty)
 {
 	if (tty->read_q) {
 		flush(tty->read_q);
 		wake_up(&tty->read_q->proc_list);
 	}
 	if (tty->secondary) {
 		flush(tty->secondary);
 		tty->secondary->data = 0;
 	}
 	if ((tty = tty->link) && tty->write_q) {
 		flush(tty->write_q);
 		wake_up(&tty->write_q->proc_list);
 	}
 }

 void flush_output(struct tty_struct * tty)
 {
 	if (tty->write_q) {
 		flush(tty->write_q);
 		wake_up(&tty->write_q->proc_list);
 	}
 	if (tty = tty->link) {
 		if (tty->read_q) {
 			flush(tty->read_q);
 			wake_up(&tty->read_q->proc_list);
 		}
 		if (tty->secondary) {
 			flush(tty->secondary);
 			tty->secondary->data = 0;
 		}
 	}
 }

 static void wait_until_sent(struct tty_struct * tty)
 {
 	while (!(current->signal & ~current->blocked) && !EMPTY(tty->write_q)) {
 		TTY_WRITE_FLUSH(tty);
 		current->counter = 0;
 		cli();
 		if (EMPTY(tty->write_q))
 			break;
 		else
 			interruptible_sleep_on(&tty->write_q->proc_list);
 		sti();
 	}
 	sti();
 }

 static int do_get_ps_info(int arg)
 {
 	struct tstruct {
 		int flag;
 		int present[NR_TASKS];
 		struct task_struct tasks[NR_TASKS];
 	};
 	struct tstruct *ts = (struct tstruct *)arg;
 	struct task_struct **p;
 	char *c, *d;
 	int i, n = 0;

 	verify_area((void *)arg, sizeof(struct tstruct));

 	for (p = &FIRST_TASK ; p <= &LAST_TASK ; p++, n++)
 		if (*p)
 		{
 			c = (char *)(*p);
 			d = (char *)(ts->tasks+n);
 			for (i=0 ; i<sizeof(struct task_struct) ; i++)
 				put_fs_byte(*c++, d++);
 			put_fs_long(1, (unsigned long *)(ts->present+n));
 		}
 		else
 			put_fs_long(0, (unsigned long *)(ts->present+n));
 	return(0);
 }

 static int get_termios(struct tty_struct * tty, struct termios * termios)
 {
 	int i;

 	verify_area(termios, sizeof (*termios));
 	for (i=0 ; i< (sizeof (*termios)) ; i++)
 		put_fs_byte( ((char *)&tty->termios)[i] , i+(char *)termios );
 	return 0;
 }

 static int set_termios(struct tty_struct * tty, struct termios * termios,
 			int channel)
 {
 	int i;

 	/* If we try to set the state of terminal and we're not in the
 	   foreground, send a SIGTTOU.  If the signal is blocked or
 	   ignored, go ahead and perform the operation.  POSIX 7.2) */
 	if ((current->tty == channel) &&
 	     (tty->pgrp != current->pgrp)) {
 		if (is_orphaned_pgrp(current->pgrp))
 			return -EIO;
 		if (!is_ignored(SIGTTOU))
 			return tty_signal(SIGTTOU, tty);
 	}
 	for (i=0 ; i< (sizeof (*termios)) ; i++)
 		((char *)&tty->termios)[i]=get_fs_byte(i+(char *)termios);
 	if (IS_A_SERIAL(channel))
 		change_speed(channel-64);
 	return 0;
 }

 static int get_termio(struct tty_struct * tty, struct termio * termio)
 {
 	int i;
 	struct termio tmp_termio;

 	verify_area(termio, sizeof (*termio));
 	tmp_termio.c_iflag = tty->termios.c_iflag;
 	tmp_termio.c_oflag = tty->termios.c_oflag;
 	tmp_termio.c_cflag = tty->termios.c_cflag;
 	tmp_termio.c_lflag = tty->termios.c_lflag;
 	tmp_termio.c_line = tty->termios.c_line;
 	for(i=0 ; i < NCC ; i++)
 		tmp_termio.c_cc[i] = tty->termios.c_cc[i];
 	for (i=0 ; i< (sizeof (*termio)) ; i++)
 		put_fs_byte( ((char *)&tmp_termio)[i] , i+(char *)termio );
 	return 0;
 }

 /*
  * This only works as the 386 is low-byte-first
  */
 static int set_termio(struct tty_struct * tty, struct termio * termio,
 			int channel)
 {
 	int i;
 	struct termio tmp_termio;

 	if ((current->tty == channel) &&
 	    (tty->pgrp > 0) &&
 	    (tty->pgrp != current->pgrp)) {
 		if (is_orphaned_pgrp(current->pgrp))
 			return -EIO;
 		if (!is_ignored(SIGTTOU))
 			return tty_signal(SIGTTOU, tty);
 	}
 	for (i=0 ; i< (sizeof (*termio)) ; i++)
 		((char *)&tmp_termio)[i]=get_fs_byte(i+(char *)termio);
 	*(unsigned short *)&tty->termios.c_iflag = tmp_termio.c_iflag;
 	*(unsigned short *)&tty->termios.c_oflag = tmp_termio.c_oflag;
 	*(unsigned short *)&tty->termios.c_cflag = tmp_termio.c_cflag;
 	*(unsigned short *)&tty->termios.c_lflag = tmp_termio.c_lflag;
 	tty->termios.c_line = tmp_termio.c_line;
 	for(i=0 ; i < NCC ; i++)
 		tty->termios.c_cc[i] = tmp_termio.c_cc[i];
 	if (IS_A_SERIAL(channel))
 		change_speed(channel-64);
 	return 0;
 }

 static int set_window_size(struct tty_struct * tty, struct winsize * ws)
 {
 	int i,changed;
 	char c, * tmp;

 	if (!ws)
 		return -EINVAL;
 	tmp = (char *) &tty->winsize;
 	changed = 0;
 	for (i = 0; i < sizeof (*ws) ; i++,tmp++) {
 		c = get_fs_byte(i + (char *) ws);
 		if (c == *tmp)
 			continue;
 		changed = 1;
 		*tmp = c;
 	}
 	if (changed)
 		kill_pg(tty->pgrp, SIGWINCH, 1);
 	return 0;
 }

 static int get_window_size(struct tty_struct * tty, struct winsize * ws)
 {
 	int i;
 	char * tmp;

 	if (!ws)
 		return -EINVAL;
 	verify_area(ws, sizeof (*ws));
 	tmp = (char *) ws;
 	for (i = 0; i < sizeof (struct winsize) ; i++,tmp++)
 		put_fs_byte(((char *) &tty->winsize)[i], tmp);
 	return 0;
 }

 int tty_ioctl(struct inode * inode, struct file * file,
 	unsigned int cmd, unsigned int arg)
 {
 	struct tty_struct * tty;
 	struct tty_struct * other_tty;
 	int pgrp;
 	int dev;

 	if (MAJOR(inode->i_rdev) == 5) {
 		dev = current->tty;
 		if (dev<0)
 			return -EINVAL;
 	} else
 		dev = MINOR(inode->i_rdev);
 	tty = tty_table + (dev ? ((dev < 64)? dev-1:dev) : fg_console);

 	if (IS_A_PTY(dev))
 		other_tty = tty_table + PTY_OTHER(dev);
 	else
 		other_tty = NULL;

 	if (!(tty->write_q && tty->read_q && tty->secondary && tty->write))
 		return -EINVAL;
 	switch (cmd) {
 		case TCGETS:
 			return get_termios(tty,(struct termios *) arg);
 		case TCSETSF:
 			flush_input(tty);
 		/* fallthrough */
 		case TCSETSW:
 			wait_until_sent(tty);
 		/* fallthrough */
 		case TCSETS:
 			return set_termios(tty,(struct termios *) arg, dev);
 		case TCGETA:
 			return get_termio(tty,(struct termio *) arg);
 		case TCSETAF:
 			flush_input(tty);
 		/* fallthrough */
 		case TCSETAW:
 			wait_until_sent(tty); /* fallthrough */
 		case TCSETA:
 			return set_termio(tty,(struct termio *) arg, dev);
 		case TCSBRK:
 			if (!IS_A_SERIAL(dev))
 				return -EINVAL;
 			wait_until_sent(tty);
 			if (!arg)
 				send_break(dev-64);
 			return 0;
 		case TCXONC:
 			switch (arg) {
 			case TCOOFF:
 				tty->stopped = 1;
 				TTY_WRITE_FLUSH(tty);
 				return 0;
 			case TCOON:
 				tty->stopped = 0;
 				TTY_WRITE_FLUSH(tty);
 				return 0;
 			case TCIOFF:
 				if (STOP_CHAR(tty))
 					PUTCH(STOP_CHAR(tty),tty->write_q);
 				return 0;
 			case TCION:
 				if (START_CHAR(tty))
 					PUTCH(START_CHAR(tty),tty->write_q);
 				return 0;
 			}
 			return -EINVAL; /* not implemented */
 		case TCFLSH:
 			if (arg==0)
 				flush_input(tty);
 			else if (arg==1)
 				flush_output(tty);
 			else if (arg==2) {
 				flush_input(tty);
 				flush_output(tty);
 			} else
 				return -EINVAL;
 			return 0;
 		case TIOCEXCL:
 			return -EINVAL; /* not implemented */
 		case TIOCNXCL:
 			return -EINVAL; /* not implemented */
 		case TIOCSCTTY:
 			return -EINVAL; /* set controlling term NI */
 		case TIOCGPGRP:
 			verify_area((void *) arg,4);
 			put_fs_long(tty->pgrp,(unsigned long *) arg);
 			return 0;
 		case TIOCSPGRP:
 			if ((current->tty < 0) ||
 			    (current->tty != dev) ||
 			    (tty->session != current->session))
 				return -ENOTTY;
 			pgrp=get_fs_long((unsigned long *) arg);
 			if (pgrp < 0)
 				return -EINVAL;
 			if (session_of_pgrp(pgrp) != current->session)
 				return -EPERM;
 			tty->pgrp = pgrp;
 			return 0;
 		case TIOCOUTQ:
 			verify_area((void *) arg,4);
 			put_fs_long(CHARS(tty->write_q),(unsigned long *) arg);
 			return 0;
 		case TIOCINQ:
 			verify_area((void *) arg,4);
 			if (L_CANON(tty) && !tty->secondary->data)
 				put_fs_long(0, (unsigned long *) arg);
 			else
 				put_fs_long(CHARS(tty->secondary),
 					(unsigned long *) arg);
 			return 0;
 		case TIOCSTI:
 			return -EINVAL; /* not implemented */
 		case TIOCGWINSZ:
 			return get_window_size(tty,(struct winsize *) arg);
 		case TIOCSWINSZ:
 			if (IS_A_PTY_MASTER(dev))
 				set_window_size(other_tty,(struct winsize *) arg);
 			return set_window_size(tty,(struct winsize *) arg);
 		case TIOCMGET:
 			return -EINVAL; /* not implemented */
 		case TIOCMBIS:
 			return -EINVAL; /* not implemented */
 		case TIOCMBIC:
 			return -EINVAL; /* not implemented */
 		case TIOCMSET:
 			return -EINVAL; /* not implemented */
 		case TIOCGSOFTCAR:
 			return -EINVAL; /* not implemented */
 		case TIOCSSOFTCAR:
 			return -EINVAL; /* not implemented */
 		case TIOCLINUX:
 			switch (get_fs_byte((char *)arg))
 			{
 				case 0:
 					return do_screendump(arg);
 				case 1:
 					return do_get_ps_info(arg);
 				default:
 					return -EINVAL;
 			}
 		case TIOCCONS:
 			if (!IS_A_PTY(dev))
 				return -EINVAL;
 			if (redirect)
 				return -EBUSY;
 			if (!suser())
 				return -EPERM;
 			if (IS_A_PTY_MASTER(dev))
 				redirect = other_tty;
 			else
 				redirect = tty;
 			return 0;
 		case TIOCGSERIAL:
 			if (!IS_A_SERIAL(dev))
 				return -EINVAL;
 			verify_area((void *) arg,sizeof(struct serial_struct));
 			return get_serial_info(dev-64,(struct serial_struct *) arg);
 		case TIOCSSERIAL:
 			if (!IS_A_SERIAL(dev))
 				return -EINVAL;
 			return set_serial_info(dev-64,(struct serial_struct *) arg);
 		default:
 			return vt_ioctl(tty, dev, cmd, arg);
 	}
 }
	/*
	* linux/kernel/chr_drv/tty_ioctl.c
	*
	* (C) 1991 Linus Torvalds
	*/

	#include <errno.h>
	#include <termios.h>
	#include <sys/types.h>

	#include <linux/sched.h>
	#include <linux/kernel.h>
	#include <linux/tty.h>

	#include <asm/io.h>
	#include <asm/segment.h>
	#include <asm/system.h>

	extern int session_of_pgrp(int pgrp);
	extern int do_screendump(int arg);
	extern int kill_pg(int pgrp, int sig, int priv);
	extern int vt_ioctl(struct tty_struct *tty, int dev, int cmd, int arg);

	static void flush(struct tty_queue * queue)
	{
	if (queue) {
	cli();
	queue->head = queue->tail;
	sti();
	wake_up(&queue->proc_list);
	}
	}

	void flush_input(struct tty_struct * tty)
	{
	if (tty->read_q) {
	flush(tty->read_q);
	wake_up(&tty->read_q->proc_list);
	}
	if (tty->secondary) {
	flush(tty->secondary);
	tty->secondary->data = 0;
	}
	if ((tty = tty->link) && tty->write_q) {
	flush(tty->write_q);
	wake_up(&tty->write_q->proc_list);
	}
	}

	void flush_output(struct tty_struct * tty)
	{
	if (tty->write_q) {
	flush(tty->write_q);
	wake_up(&tty->write_q->proc_list);
	}
	if (tty = tty->link) {
	if (tty->read_q) {
	flush(tty->read_q);
	wake_up(&tty->read_q->proc_list);
	}
	if (tty->secondary) {
	flush(tty->secondary);
	tty->secondary->data = 0;
	}
	}
	}

	static void wait_until_sent(struct tty_struct * tty)
	{
	while (!(current->signal & ~current->blocked) && !EMPTY(tty->write_q)) {
	TTY_WRITE_FLUSH(tty);
	current->counter = 0;
	cli();
	if (EMPTY(tty->write_q))
	break;
	else
	interruptible_sleep_on(&tty->write_q->proc_list);
	sti();
	}
	sti();
	}

	static int do_get_ps_info(int arg)
	{
	struct tstruct {
	int flag;
	int present[NR_TASKS];
	struct task_struct tasks[NR_TASKS];
	};
	struct tstruct ts = (struct tstruct )arg;
	struct task_struct **p;
	char c, d;
	int i, n = 0;

	verify_area((void *)arg, sizeof(struct tstruct));

	for (p = &FIRST_TASK ; p <= &LAST_TASK ; p++, n++)
	if (*p)
	{
	c = (char )(p);
	d = (char *)(ts->tasks+n);
	for (i=0 ; i<sizeof(struct task_struct) ; i++)
	put_fs_byte(*c++, d++);
	put_fs_long(1, (unsigned long *)(ts->present+n));
	}
	else
	put_fs_long(0, (unsigned long *)(ts->present+n));
	return(0);
	}

	static int get_termios(struct tty_struct * tty, struct termios * termios)
	{
	int i;

	verify_area(termios, sizeof (*termios));
	for (i=0 ; i< (sizeof (*termios)) ; i++)
	put_fs_byte( ((char )&tty->termios)[i] , i+(char )termios );
	return 0;
	}

	static int set_termios(struct tty_struct * tty, struct termios * termios,
	int channel)
	{
	int i;

	/* If we try to set the state of terminal and we're not in the
	foreground, send a SIGTTOU. If the signal is blocked or
	ignored, go ahead and perform the operation. POSIX 7.2) */
	if ((current->tty == channel) &&
	(tty->pgrp != current->pgrp)) {
	if (is_orphaned_pgrp(current->pgrp))
	return -EIO;
	if (!is_ignored(SIGTTOU))
	return tty_signal(SIGTTOU, tty);
	}
	for (i=0 ; i< (sizeof (*termios)) ; i++)
	((char )&tty->termios)[i]=get_fs_byte(i+(char )termios);
	if (IS_A_SERIAL(channel))
	change_speed(channel-64);
	return 0;
	}

	static int get_termio(struct tty_struct * tty, struct termio * termio)
	{
	int i;
	struct termio tmp_termio;

	verify_area(termio, sizeof (*termio));
	tmp_termio.c_iflag = tty->termios.c_iflag;
	tmp_termio.c_oflag = tty->termios.c_oflag;
	tmp_termio.c_cflag = tty->termios.c_cflag;
	tmp_termio.c_lflag = tty->termios.c_lflag;
	tmp_termio.c_line = tty->termios.c_line;
	for(i=0 ; i < NCC ; i++)
	tmp_termio.c_cc[i] = tty->termios.c_cc[i];
	for (i=0 ; i< (sizeof (*termio)) ; i++)
	put_fs_byte( ((char )&tmp_termio)[i] , i+(char )termio );
	return 0;
	}

	/*
	* This only works as the 386 is low-byte-first
	*/
	static int set_termio(struct tty_struct * tty, struct termio * termio,
	int channel)
	{
	int i;
	struct termio tmp_termio;

	if ((current->tty == channel) &&
	(tty->pgrp > 0) &&
	(tty->pgrp != current->pgrp)) {
	if (is_orphaned_pgrp(current->pgrp))
	return -EIO;
	if (!is_ignored(SIGTTOU))
	return tty_signal(SIGTTOU, tty);
	}
	for (i=0 ; i< (sizeof (*termio)) ; i++)
	((char )&tmp_termio)[i]=get_fs_byte(i+(char )termio);
	(unsigned short )&tty->termios.c_iflag = tmp_termio.c_iflag;
	(unsigned short )&tty->termios.c_oflag = tmp_termio.c_oflag;
	(unsigned short )&tty->termios.c_cflag = tmp_termio.c_cflag;
	(unsigned short )&tty->termios.c_lflag = tmp_termio.c_lflag;
	tty->termios.c_line = tmp_termio.c_line;
	for(i=0 ; i < NCC ; i++)
	tty->termios.c_cc[i] = tmp_termio.c_cc[i];
	if (IS_A_SERIAL(channel))
	change_speed(channel-64);
	return 0;
	}

	static int set_window_size(struct tty_struct * tty, struct winsize * ws)
	{
	int i,changed;
	char c, * tmp;

	if (!ws)
	return -EINVAL;
	tmp = (char *) &tty->winsize;
	changed = 0;
	for (i = 0; i < sizeof (*ws) ; i++,tmp++) {
	c = get_fs_byte(i + (char *) ws);
	if (c == *tmp)
	continue;
	changed = 1;
	*tmp = c;
	}
	if (changed)
	kill_pg(tty->pgrp, SIGWINCH, 1);
	return 0;
	}

	static int get_window_size(struct tty_struct * tty, struct winsize * ws)
	{
	int i;
	char * tmp;

	if (!ws)
	return -EINVAL;
	verify_area(ws, sizeof (*ws));
	tmp = (char *) ws;
	for (i = 0; i < sizeof (struct winsize) ; i++,tmp++)
	put_fs_byte(((char *) &tty->winsize)[i], tmp);
	return 0;
	}

	int tty_ioctl(struct inode * inode, struct file * file,
	unsigned int cmd, unsigned int arg)
	{
	struct tty_struct * tty;
	struct tty_struct * other_tty;
	int pgrp;
	int dev;

	if (MAJOR(inode->i_rdev) == 5) {
	dev = current->tty;
	if (dev<0)
	return -EINVAL;
	} else
	dev = MINOR(inode->i_rdev);
	tty = tty_table + (dev ? ((dev < 64)? dev-1:dev) : fg_console);

	if (IS_A_PTY(dev))
	other_tty = tty_table + PTY_OTHER(dev);
	else
	other_tty = NULL;

	if (!(tty->write_q && tty->read_q && tty->secondary && tty->write))
	return -EINVAL;
	switch (cmd) {
	case TCGETS:
	return get_termios(tty,(struct termios *) arg);
	case TCSETSF:
	flush_input(tty);
	/* fallthrough */
	case TCSETSW:
	wait_until_sent(tty);
	/* fallthrough */
	case TCSETS:
	return set_termios(tty,(struct termios *) arg, dev);
	case TCGETA:
	return get_termio(tty,(struct termio *) arg);
	case TCSETAF:
	flush_input(tty);
	/* fallthrough */
	case TCSETAW:
	wait_until_sent(tty); /* fallthrough */
	case TCSETA:
	return set_termio(tty,(struct termio *) arg, dev);
	case TCSBRK:
	if (!IS_A_SERIAL(dev))
	return -EINVAL;
	wait_until_sent(tty);
	if (!arg)
	send_break(dev-64);
	return 0;
	case TCXONC:
	switch (arg) {
	case TCOOFF:
	tty->stopped = 1;
	TTY_WRITE_FLUSH(tty);
	return 0;
	case TCOON:
	tty->stopped = 0;
	TTY_WRITE_FLUSH(tty);
	return 0;
	case TCIOFF:
	if (STOP_CHAR(tty))
	PUTCH(STOP_CHAR(tty),tty->write_q);
	return 0;
	case TCION:
	if (START_CHAR(tty))
	PUTCH(START_CHAR(tty),tty->write_q);
	return 0;
	}
	return -EINVAL; /* not implemented */
	case TCFLSH:
	if (arg==0)
	flush_input(tty);
	else if (arg==1)
	flush_output(tty);
	else if (arg==2) {
	flush_input(tty);
	flush_output(tty);
	} else
	return -EINVAL;
	return 0;
	case TIOCEXCL:
	return -EINVAL; /* not implemented */
	case TIOCNXCL:
	return -EINVAL; /* not implemented */
	case TIOCSCTTY:
	return -EINVAL; /* set controlling term NI */
	case TIOCGPGRP:
	verify_area((void *) arg,4);
	put_fs_long(tty->pgrp,(unsigned long *) arg);
	return 0;
	case TIOCSPGRP:
	if ((current->tty < 0) \|\|
	(current->tty != dev) \|\|
	(tty->session != current->session))
	return -ENOTTY;
	pgrp=get_fs_long((unsigned long *) arg);
	if (pgrp < 0)
	return -EINVAL;
	if (session_of_pgrp(pgrp) != current->session)
	return -EPERM;
	tty->pgrp = pgrp;
	return 0;
	case TIOCOUTQ:
	verify_area((void *) arg,4);
	put_fs_long(CHARS(tty->write_q),(unsigned long *) arg);
	return 0;
	case TIOCINQ:
	verify_area((void *) arg,4);
	if (L_CANON(tty) && !tty->secondary->data)
	put_fs_long(0, (unsigned long *) arg);
	else
	put_fs_long(CHARS(tty->secondary),
	(unsigned long *) arg);
	return 0;
	case TIOCSTI:
	return -EINVAL; /* not implemented */
	case TIOCGWINSZ:
	return get_window_size(tty,(struct winsize *) arg);
	case TIOCSWINSZ:
	if (IS_A_PTY_MASTER(dev))
	set_window_size(other_tty,(struct winsize *) arg);
	return set_window_size(tty,(struct winsize *) arg);
	case TIOCMGET:
	return -EINVAL; /* not implemented */
	case TIOCMBIS:
	return -EINVAL; /* not implemented */
	case TIOCMBIC:
	return -EINVAL; /* not implemented */
	case TIOCMSET:
	return -EINVAL; /* not implemented */
	case TIOCGSOFTCAR:
	return -EINVAL; /* not implemented */
	case TIOCSSOFTCAR:
	return -EINVAL; /* not implemented */
	case TIOCLINUX:
	switch (get_fs_byte((char *)arg))
	{
	case 0:
	return do_screendump(arg);
	case 1:
	return do_get_ps_info(arg);
	default:
	return -EINVAL;
	}
	case TIOCCONS:
	if (!IS_A_PTY(dev))
	return -EINVAL;
	if (redirect)
	return -EBUSY;
	if (!suser())
	return -EPERM;
	if (IS_A_PTY_MASTER(dev))
	redirect = other_tty;
	else
	redirect = tty;
	return 0;
	case TIOCGSERIAL:
	if (!IS_A_SERIAL(dev))
	return -EINVAL;
	verify_area((void *) arg,sizeof(struct serial_struct));
	return get_serial_info(dev-64,(struct serial_struct *) arg);
	case TIOCSSERIAL:
	if (!IS_A_SERIAL(dev))
	return -EINVAL;
	return set_serial_info(dev-64,(struct serial_struct *) arg);
	default:
	return vt_ioctl(tty, dev, cmd, arg);
	}
	}