Commit b82154ac authored by Jiri Slaby's avatar Jiri Slaby Committed by Greg Kroah-Hartman
Browse files

TTY: extract /dev/tty handling from tty_open 



This one is special to others (done in the next patch). We have the
tty directly, not its driver and index. So this will reside in a
separation function. In the next patch, the rest will be moved to
another function.

So now we set neither driver nor index. Hence we need to init driver
and check whether we are supposed to put a ref of that.

Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent 1411dc4a

drivers/tty/tty_io.c

+39 −18
Original line number Diff line number Diff line
@@ -1796,6 +1796,33 @@ int tty_release(struct inode *inode, struct file *filp) 
	return 0;

}



/**

 *	tty_open_current_tty - get tty of current task for open

 *	@device: device number

 *	@filp: file pointer to tty

 *	@return: tty of the current task iff @device is /dev/tty

 *

 *	We cannot return driver and index like for the other nodes because

 *	devpts will not work then. It expects inodes to be from devpts FS.

 */

static struct tty_struct *tty_open_current_tty(dev_t device, struct file *filp)

{

	struct tty_struct *tty;



	if (device != MKDEV(TTYAUX_MAJOR, 0))

		return NULL;



	tty = get_current_tty();

	if (!tty)

		return ERR_PTR(-ENXIO);



	filp->f_flags |= O_NONBLOCK; /* Don't let /dev/tty block */

	/* noctty = 1; */

	tty_kref_put(tty);

	/* FIXME: we put a reference and return a TTY! */

	return tty;

}



/**

 *	tty_open		-	open a tty device

 *	@inode: inode of device file
@@ -1819,9 +1846,9 @@ int tty_release(struct inode *inode, struct file *filp) 


static int tty_open(struct inode *inode, struct file *filp)

{

	struct tty_struct *tty = NULL;

	struct tty_struct *tty;

	int noctty, retval;

	struct tty_driver *driver;

	struct tty_driver *driver = NULL;

	int index;

	dev_t device = inode->i_rdev;

	unsigned saved_flags = filp->f_flags;
@@ -1840,22 +1867,15 @@ retry_open: 
	mutex_lock(&tty_mutex);

	tty_lock();



	if (device == MKDEV(TTYAUX_MAJOR, 0)) {

		tty = get_current_tty();

		if (!tty) {

	tty = tty_open_current_tty(device, filp);

	if (IS_ERR(tty)) {

		tty_unlock();

		mutex_unlock(&tty_mutex);

		tty_free_file(filp);

			return -ENXIO;

		}

		driver = tty_driver_kref_get(tty->driver);

		index = tty->index;

		filp->f_flags |= O_NONBLOCK; /* Don't let /dev/tty block */

		/* noctty = 1; */

		/* FIXME: Should we take a driver reference ? */

		tty_kref_put(tty);

		return PTR_ERR(tty);

	} else if (tty)

		goto got_driver;

	}



#ifdef CONFIG_VT

	if (device == MKDEV(TTY_MAJOR, 0)) {

		extern struct tty_driver *console_driver;
@@ -1911,6 +1931,7 @@ got_driver: 
		tty = tty_init_dev(driver, index, 0);



	mutex_unlock(&tty_mutex);

	if (driver)

		tty_driver_kref_put(driver);

	if (IS_ERR(tty)) {

		tty_unlock();

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