Commit 807c8d81 authored by Peter Hurley's avatar Peter Hurley Committed by Greg Kroah-Hartman
Browse files

tty: Replace ASYNC_NORMAL_ACTIVE bit and update atomically 



Replace ASYNC_NORMAL_ACTIVE bit in the tty_port::flags field with
TTY_PORT_ACTIVE bit in the tty_port::iflags field. Introduce helpers
tty_port_set_active() and tty_port_active() to abstract atomic bit ops.

Extract state changes from port lock sections, as this usage is
broken and confused; the state transitions are protected by the
tty lock (which mutually excludes parallel open/close/hangup),
and no user tests the active state while holding the port lock.

Signed-off-by: default avatarPeter Hurley <peter@hurleysoftware.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 5604a98e

drivers/isdn/i4l/isdn_tty.c

+9 −11
Original line number Diff line number Diff line
@@ -1622,7 +1622,7 @@ isdn_tty_hangup(struct tty_struct *tty) 
		return;

	isdn_tty_shutdown(info);

	port->count = 0;

	port->flags &= ~ASYNC_NORMAL_ACTIVE;

	tty_port_set_active(port, 0);

	port->tty = NULL;

	wake_up_interruptible(&port->open_wait);

}
@@ -1979,7 +1979,7 @@ isdn_tty_find_icall(int di, int ch, setup_parm *setup) 
#endif

			if (

#ifndef FIX_FILE_TRANSFER

				(info->port.flags & ASYNC_NORMAL_ACTIVE) &&

			    tty_port_active(&info->port) &&

#endif

				(info->isdn_driver == -1) &&

				(info->isdn_channel == -1) &&
@@ -2018,8 +2018,6 @@ isdn_tty_find_icall(int di, int ch, setup_parm *setup) 
	return (wret == 2) ? 3 : 0;

}



#define TTY_IS_ACTIVE(info)	(info->port.flags & ASYNC_NORMAL_ACTIVE)



int

isdn_tty_stat_callback(int i, isdn_ctrl *c)

{
@@ -2077,7 +2075,7 @@ isdn_tty_stat_callback(int i, isdn_ctrl *c) 
#ifdef ISDN_TTY_STAT_DEBUG

			printk(KERN_DEBUG "tty_STAT_DCONN ttyI%d\n", info->line);

#endif

			if (TTY_IS_ACTIVE(info)) {

			if (tty_port_active(&info->port)) {

				if (info->dialing == 1) {

					info->dialing = 2;

					return 1;
@@ -2088,7 +2086,7 @@ isdn_tty_stat_callback(int i, isdn_ctrl *c) 
#ifdef ISDN_TTY_STAT_DEBUG

			printk(KERN_DEBUG "tty_STAT_DHUP ttyI%d\n", info->line);

#endif

			if (TTY_IS_ACTIVE(info)) {

			if (tty_port_active(&info->port)) {

				if (info->dialing == 1)

					isdn_tty_modem_result(RESULT_BUSY, info);

				if (info->dialing > 1)
@@ -2118,7 +2116,7 @@ isdn_tty_stat_callback(int i, isdn_ctrl *c) 
			 * waiting for it and

			 * set DCD-bit of its modem-status.

			 */

			if (TTY_IS_ACTIVE(info) ||

			if (tty_port_active(&info->port) ||

			    (info->port.blocked_open &&

			     (info->emu.mdmreg[REG_DCD] & BIT_DCD))) {

				info->msr |= UART_MSR_DCD;
@@ -2145,7 +2143,7 @@ isdn_tty_stat_callback(int i, isdn_ctrl *c) 
#ifdef ISDN_TTY_STAT_DEBUG

			printk(KERN_DEBUG "tty_STAT_BHUP ttyI%d\n", info->line);

#endif

			if (TTY_IS_ACTIVE(info)) {

			if (tty_port_active(&info->port)) {

#ifdef ISDN_DEBUG_MODEM_HUP

				printk(KERN_DEBUG "Mhup in ISDN_STAT_BHUP\n");

#endif
@@ -2157,7 +2155,7 @@ isdn_tty_stat_callback(int i, isdn_ctrl *c) 
#ifdef ISDN_TTY_STAT_DEBUG

			printk(KERN_DEBUG "tty_STAT_NODCH ttyI%d\n", info->line);

#endif

			if (TTY_IS_ACTIVE(info)) {

			if (tty_port_active(&info->port)) {

				if (info->dialing) {

					info->dialing = 0;

					info->last_l2 = -1;
@@ -2183,14 +2181,14 @@ isdn_tty_stat_callback(int i, isdn_ctrl *c) 
			return 1;

#ifdef CONFIG_ISDN_TTY_FAX

		case ISDN_STAT_FAXIND:

			if (TTY_IS_ACTIVE(info)) {

			if (tty_port_active(&info->port)) {

				isdn_tty_fax_command(info, c);

			}

			break;

#endif

#ifdef CONFIG_ISDN_AUDIO

		case ISDN_STAT_AUDIO:

			if (TTY_IS_ACTIVE(info)) {

			if (tty_port_active(&info->port)) {

				switch (c->parm.num[0]) {

				case ISDN_AUDIO_DTMF:

					if (info->vonline) {

drivers/tty/amiserial.c

+1 −1
Original line number Diff line number Diff line
@@ -1493,7 +1493,7 @@ static void rs_hangup(struct tty_struct *tty) 
	rs_flush_buffer(tty);

	shutdown(tty, info);

	info->tport.count = 0;

	info->tport.flags &= ~ASYNC_NORMAL_ACTIVE;

	tty_port_set_active(&info->tport, 0);

	info->tport.tty = NULL;

	wake_up_interruptible(&info->tport.open_wait);

}

drivers/tty/rocket.c

+3 −2
Original line number Diff line number Diff line
@@ -1042,9 +1042,10 @@ static void rp_close(struct tty_struct *tty, struct file *filp) 
		}

	}

	spin_lock_irq(&port->lock);

	info->port.flags &= ~(ASYNC_INITIALIZED | ASYNC_NORMAL_ACTIVE);

	port->flags &= ~ASYNC_INITIALIZED;

	tty->closing = 0;

	spin_unlock_irq(&port->lock);

	tty_port_set_active(port, 0);

	mutex_unlock(&port->mutex);

	tty_port_tty_set(port, NULL);
@@ -1624,7 +1625,7 @@ static int rp_write(struct tty_struct *tty, 
	/*  Write remaining data into the port's xmit_buf */

	while (1) {

		/* Hung up ? */

		if (!test_bit(ASYNCB_NORMAL_ACTIVE, &info->port.flags))

		if (!tty_port_active(&info->port))

			goto end;

		c = min(count, XMIT_BUF_SIZE - info->xmit_cnt - 1);

		c = min(c, XMIT_BUF_SIZE - info->xmit_head);

drivers/tty/serial/crisv10.c

+4 −4
Original line number Diff line number Diff line
@@ -3648,8 +3648,8 @@ rs_close(struct tty_struct *tty, struct file * filp) 
			schedule_timeout_interruptible(info->port.close_delay);

		wake_up_interruptible(&info->port.open_wait);

	}

	info->port.flags &= ~ASYNC_NORMAL_ACTIVE;

	local_irq_restore(flags);

	tty_port_set_active(&info->port, 0);



	/* port closed */
@@ -3732,7 +3732,7 @@ rs_hangup(struct tty_struct *tty) 
	shutdown(info);

	info->event = 0;

	info->port.count = 0;

	info->port.flags &= ~ASYNC_NORMAL_ACTIVE;

	tty_port_set_active(&info->port, 0);

	info->port.tty = NULL;

	wake_up_interruptible(&info->port.open_wait);

}
@@ -3756,7 +3756,7 @@ block_til_ready(struct tty_struct *tty, struct file * filp, 
	 * then make the check up front and then exit.

	 */

	if ((filp->f_flags & O_NONBLOCK) || tty_io_error(tty)) {

		info->port.flags |= ASYNC_NORMAL_ACTIVE;

		tty_port_set_active(&info->port, 1);

		return 0;

	}
@@ -3825,7 +3825,7 @@ block_til_ready(struct tty_struct *tty, struct file * filp, 
#endif

	if (retval)

		return retval;

	info->port.flags |= ASYNC_NORMAL_ACTIVE;

	tty_port_set_active(&info->port, 1);

	return 0;

}

drivers/tty/serial/serial_core.c

+4 −4
Original line number Diff line number Diff line
@@ -1418,12 +1418,12 @@ static void uart_close(struct tty_struct *tty, struct file *filp) 
		uart_change_pm(state, UART_PM_STATE_OFF);

		spin_lock_irq(&port->lock);

	}

	spin_unlock_irq(&port->lock);

	tty_port_set_active(port, 0);



	/*

	 * Wake up anyone trying to open this port.

	 */

	clear_bit(ASYNCB_NORMAL_ACTIVE, &port->flags);

	spin_unlock_irq(&port->lock);

	wake_up_interruptible(&port->open_wait);



	mutex_unlock(&port->mutex);
@@ -1501,13 +1501,13 @@ static void uart_hangup(struct tty_struct *tty) 
	pr_debug("uart_hangup(%d)\n", tty->index);



	mutex_lock(&port->mutex);

	if (port->flags & ASYNC_NORMAL_ACTIVE) {

	if (tty_port_active(port)) {

		uart_flush_buffer(tty);

		uart_shutdown(tty, state);

		spin_lock_irqsave(&port->lock, flags);

		port->count = 0;

		clear_bit(ASYNCB_NORMAL_ACTIVE, &port->flags);

		spin_unlock_irqrestore(&port->lock, flags);

		tty_port_set_active(port, 0);

		tty_port_tty_set(port, NULL);

		if (!uart_console(state->uart_port))

			uart_change_pm(state, UART_PM_STATE_OFF);

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