Commit fc6f6238 authored by Alan Cox's avatar Alan Cox Committed by Linus Torvalds
Browse files

pty: simplify resize 



We have special case logic for resizing pty/tty pairs. We also have a per
driver resize method so for the pty case we should use it.

Signed-off-by: default avatarAlan Cox <alan@redhat.com>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent a47d545f

drivers/char/hvc_console.c

+1 −1
Original line number Diff line number Diff line
@@ -529,7 +529,7 @@ static void hvc_set_winsz(struct work_struct *work) 
	tty = tty_kref_get(hp->tty);

	spin_unlock_irqrestore(&hp->lock, hvc_flags);



	tty_do_resize(tty, tty, &ws);

	tty_do_resize(tty, &ws);

	tty_kref_put(tty);

}

drivers/char/pty.c

+53 −1
Original line number Diff line number Diff line
@@ -230,6 +230,55 @@ static void pty_set_termios(struct tty_struct *tty, 
	tty->termios->c_cflag |= (CS8 | CREAD);

}



/**

 *	pty_do_resize		-	resize event

 *	@tty: tty being resized

 *	@real_tty: real tty (not the same as tty if using a pty/tty pair)

 *	@rows: rows (character)

 *	@cols: cols (character)

 *

 *	Update the termios variables and send the neccessary signals to

 *	peform a terminal resize correctly

 */



int pty_resize(struct tty_struct *tty,  struct winsize *ws)

{

	struct pid *pgrp, *rpgrp;

	unsigned long flags;

	struct tty_struct *pty = tty->link;



	/* For a PTY we need to lock the tty side */

	mutex_lock(&tty->termios_mutex);

	if (!memcmp(ws, &tty->winsize, sizeof(*ws)))

		goto done;



	/* Get the PID values and reference them so we can

	   avoid holding the tty ctrl lock while sending signals.

	   We need to lock these individually however. */



	spin_lock_irqsave(&tty->ctrl_lock, flags);

	pgrp = get_pid(tty->pgrp);

	spin_unlock_irqrestore(&tty->ctrl_lock, flags);



	spin_lock_irqsave(&pty->ctrl_lock, flags);

	rpgrp = get_pid(pty->pgrp);

	spin_unlock_irqrestore(&pty->ctrl_lock, flags);



	if (pgrp)

		kill_pgrp(pgrp, SIGWINCH, 1);

	if (rpgrp != pgrp && rpgrp)

		kill_pgrp(rpgrp, SIGWINCH, 1);



	put_pid(pgrp);

	put_pid(rpgrp);



	tty->winsize = *ws;

	pty->winsize = *ws;	/* Never used so will go away soon */

done:

	mutex_unlock(&tty->termios_mutex);

	return 0;

}



static int pty_install(struct tty_driver *driver, struct tty_struct *tty)

{

	struct tty_struct *o_tty;
@@ -290,6 +339,7 @@ static const struct tty_operations pty_ops = { 
	.chars_in_buffer = pty_chars_in_buffer,

	.unthrottle = pty_unthrottle,

	.set_termios = pty_set_termios,

	.resize = pty_resize

};



/* Traditional BSD devices */
@@ -319,6 +369,7 @@ static const struct tty_operations pty_ops_bsd = { 
	.unthrottle = pty_unthrottle,

	.set_termios = pty_set_termios,

	.ioctl = pty_bsd_ioctl,

	.resize = pty_resize

};



static void __init legacy_pty_init(void)
@@ -561,7 +612,8 @@ static const struct tty_operations ptm_unix98_ops = { 
	.unthrottle = pty_unthrottle,

	.set_termios = pty_set_termios,

	.ioctl = pty_unix98_ioctl,

	.shutdown = pty_unix98_shutdown

	.shutdown = pty_unix98_shutdown,

	.resize = pty_resize

};



static const struct tty_operations pty_unix98_ops = {

drivers/char/tty_io.c

+11 −20
Original line number Diff line number Diff line
@@ -2048,7 +2048,6 @@ static int tiocgwinsz(struct tty_struct *tty, struct winsize __user *arg) 
/**

 *	tty_do_resize		-	resize event

 *	@tty: tty being resized

 *	@real_tty: real tty (not the same as tty if using a pty/tty pair)

 *	@rows: rows (character)

 *	@cols: cols (character)

 *
@@ -2056,41 +2055,34 @@ static int tiocgwinsz(struct tty_struct *tty, struct winsize __user *arg) 
 *	peform a terminal resize correctly

 */



int tty_do_resize(struct tty_struct *tty, struct tty_struct *real_tty,

					struct winsize *ws)

int tty_do_resize(struct tty_struct *tty, struct winsize *ws)

{

	struct pid *pgrp, *rpgrp;

	struct pid *pgrp;

	unsigned long flags;



	/* For a PTY we need to lock the tty side */

	mutex_lock(&real_tty->termios_mutex);

	if (!memcmp(ws, &real_tty->winsize, sizeof(*ws)))

	/* Lock the tty */

	mutex_lock(&tty->termios_mutex);

	if (!memcmp(ws, &tty->winsize, sizeof(*ws)))

		goto done;

	/* Get the PID values and reference them so we can

	   avoid holding the tty ctrl lock while sending signals */

	spin_lock_irqsave(&tty->ctrl_lock, flags);

	pgrp = get_pid(tty->pgrp);

	rpgrp = get_pid(real_tty->pgrp);

	spin_unlock_irqrestore(&tty->ctrl_lock, flags);



	if (pgrp)

		kill_pgrp(pgrp, SIGWINCH, 1);

	if (rpgrp != pgrp && rpgrp)

		kill_pgrp(rpgrp, SIGWINCH, 1);



	put_pid(pgrp);

	put_pid(rpgrp);



	tty->winsize = *ws;

	real_tty->winsize = *ws;

done:

	mutex_unlock(&real_tty->termios_mutex);

	mutex_unlock(&tty->termios_mutex);

	return 0;

}



/**

 *	tiocswinsz		-	implement window size set ioctl

 *	@tty; tty

 *	@tty; tty side of tty

 *	@arg: user buffer for result

 *

 *	Copies the user idea of the window size to the kernel. Traditionally
@@ -2103,17 +2095,16 @@ done: 
 *	then calls into the default method.

 */



static int tiocswinsz(struct tty_struct *tty, struct tty_struct *real_tty,

	struct winsize __user *arg)

static int tiocswinsz(struct tty_struct *tty, struct winsize __user *arg)

{

	struct winsize tmp_ws;

	if (copy_from_user(&tmp_ws, arg, sizeof(*arg)))

		return -EFAULT;



	if (tty->ops->resize)

		return tty->ops->resize(tty, real_tty, &tmp_ws);

		return tty->ops->resize(tty, &tmp_ws);

	else

		return tty_do_resize(tty, real_tty, &tmp_ws);

		return tty_do_resize(tty, &tmp_ws);

}



/**
@@ -2538,7 +2529,7 @@ long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg) 
	case TIOCGWINSZ:

		return tiocgwinsz(real_tty, p);

	case TIOCSWINSZ:

		return tiocswinsz(tty, real_tty, p);

		return tiocswinsz(real_tty, p);

	case TIOCCONS:

		return real_tty != tty ? -EINVAL : tioccons(file);

	case FIONBIO:

drivers/char/vt.c

+6 −8
Original line number Diff line number Diff line
@@ -819,8 +819,8 @@ static inline int resize_screen(struct vc_data *vc, int width, int height, 
 *	ctrl_lock of the tty IFF a tty is passed.

 */



static int vc_do_resize(struct tty_struct *tty, struct tty_struct *real_tty,

		struct vc_data *vc, unsigned int cols, unsigned int lines)

static int vc_do_resize(struct tty_struct *tty, struct vc_data *vc,

				unsigned int cols, unsigned int lines)

{

	unsigned long old_origin, new_origin, new_scr_end, rlth, rrem, err = 0;

	unsigned int old_cols, old_rows, old_row_size, old_screen_size;
@@ -932,7 +932,7 @@ static int vc_do_resize(struct tty_struct *tty, struct tty_struct *real_tty, 
		ws.ws_row = vc->vc_rows;

		ws.ws_col = vc->vc_cols;

		ws.ws_ypixel = vc->vc_scan_lines;

		tty_do_resize(tty, real_tty, &ws);

		tty_do_resize(tty, &ws);

	}



	if (CON_IS_VISIBLE(vc))
@@ -954,13 +954,12 @@ static int vc_do_resize(struct tty_struct *tty, struct tty_struct *real_tty, 


int vc_resize(struct vc_data *vc, unsigned int cols, unsigned int rows)

{

	return vc_do_resize(vc->vc_tty, vc->vc_tty, vc, cols, rows);

	return vc_do_resize(vc->vc_tty, vc, cols, rows);

}



/**

 *	vt_resize		-	resize a VT

 *	@tty: tty to resize

 *	@real_tty: tty if a pty/tty pair

 *	@ws: winsize attributes

 *

 *	Resize a virtual terminal. This is called by the tty layer as we
@@ -971,14 +970,13 @@ int vc_resize(struct vc_data *vc, unsigned int cols, unsigned int rows) 
 *	termios_mutex and the tty ctrl_lock in that order.

 */



int vt_resize(struct tty_struct *tty, struct tty_struct *real_tty,

	struct winsize *ws)

int vt_resize(struct tty_struct *tty, struct winsize *ws)

{

	struct vc_data *vc = tty->driver_data;

	int ret;



	acquire_console_sem();

	ret = vc_do_resize(tty, real_tty, vc, ws->ws_col, ws->ws_row);

	ret = vc_do_resize(tty, vc, ws->ws_col, ws->ws_row);

	release_console_sem();

	return ret;

}

include/linux/tty.h

+1 −2
Original line number Diff line number Diff line
@@ -360,8 +360,7 @@ extern int tty_write_room(struct tty_struct *tty); 
extern void tty_driver_flush_buffer(struct tty_struct *tty);

extern void tty_throttle(struct tty_struct *tty);

extern void tty_unthrottle(struct tty_struct *tty);

extern int tty_do_resize(struct tty_struct *tty, struct tty_struct *real_tty,

						struct winsize *ws);

extern int tty_do_resize(struct tty_struct *tty, struct winsize *ws);

extern void tty_shutdown(struct tty_struct *tty);

extern void tty_free_termios(struct tty_struct *tty);

extern int is_current_pgrp_orphaned(void);

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