Commit 73ec06fc authored by Alan Cox's avatar Alan Cox Committed by Linus Torvalds
Browse files

tty: Finish fixing up the init_dev interface to use ERR_PTR 



Original suggestion and proposal from Sukadev Bhattiprolu.

Signed-off-by: default avatarAlan Cox <alan@redhat.com>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 8b0a88d5

drivers/char/pty.c

+4 −2
Original line number Diff line number Diff line
@@ -501,11 +501,13 @@ static int __ptmx_open(struct inode *inode, struct file *filp) 
		return index;



	mutex_lock(&tty_mutex);

	retval = tty_init_dev(ptm_driver, index, &tty, 1);

	tty = tty_init_dev(ptm_driver, index, 1);

	mutex_unlock(&tty_mutex);



	if (retval)

	if (IS_ERR(tty)) {

		retval = PTR_ERR(tty);

		goto out;

	}



	set_bit(TTY_PTY_LOCK, &tty->flags); /* LOCK THE SLAVE */

	filp->private_data = tty;

drivers/char/tty_io.c

+21 −31
Original line number Diff line number Diff line
@@ -1324,35 +1324,32 @@ static int tty_reopen(struct tty_struct *tty) 
 * relaxed for the (most common) case of reopening a tty.

 */



int tty_init_dev(struct tty_driver *driver, int idx,

	struct tty_struct **ret_tty, int first_ok)

struct tty_struct *tty_init_dev(struct tty_driver *driver, int idx,

								int first_ok)

{

	struct tty_struct *tty, *o_tty;

	struct ktermios *tp, **tp_loc, *o_tp, **o_tp_loc;

	struct ktermios *ltp, **ltp_loc, *o_ltp, **o_ltp_loc;

	int retval = 0;

	int retval;



	/* check whether we're reopening an existing tty */

	tty = tty_driver_lookup_tty(driver, idx);

	if (IS_ERR(tty)) {

		retval = PTR_ERR(tty);

		goto end_init;

	}



	if (IS_ERR(tty))

		return tty;



	if (tty) {

		retval = tty_reopen(tty);

		if (retval)

			return retval;

		*ret_tty = tty;

		return 0;

			return ERR_PTR(retval);

		return tty;

	}



	/* Check if pty master is being opened multiple times */

	if (driver->subtype == PTY_TYPE_MASTER &&

		(driver->flags & TTY_DRIVER_DEVPTS_MEM) && !first_ok) {

		retval = -EIO;

		goto end_init;

	}

		(driver->flags & TTY_DRIVER_DEVPTS_MEM) && !first_ok)

		return ERR_PTR(-EIO);



	/*

	 * First time open is complex, especially for PTY devices.

	 * This code guarantees that either everything succeeds and the
@@ -1361,10 +1358,8 @@ int tty_init_dev(struct tty_driver *driver, int idx, 
	 * and locked termios may be retained.)

	 */



	if (!try_module_get(driver->owner)) {

		retval = -ENODEV;

		goto end_init;

	}

	if (!try_module_get(driver->owner))

		return ERR_PTR(-ENODEV);



	o_tty = NULL;

	tp = o_tp = NULL;
@@ -1475,7 +1470,8 @@ int tty_init_dev(struct tty_driver *driver, int idx, 
	tty_driver_kref_get(driver);

	tty->count++;



	if (tty_driver_install_tty(driver, tty) < 0)

	retval = tty_driver_install_tty(driver, tty);

	if (retval < 0)

		goto release_mem_out;



	/*
@@ -1485,14 +1481,9 @@ int tty_init_dev(struct tty_driver *driver, int idx, 
	 */



	retval = tty_ldisc_setup(tty, o_tty);



	if (retval)

		goto release_mem_out;



	*ret_tty = tty;

	/* All paths come through here to release the mutex */

end_init:

	return retval;

	return tty;



	/* Release locally allocated memory ... nothing placed in slots */

free_mem_out:
@@ -1507,8 +1498,7 @@ int tty_init_dev(struct tty_driver *driver, int idx, 


fail_no_mem:

	module_put(driver->owner);

	retval = -ENOMEM;

	goto end_init;

	return ERR_PTR(-ENOMEM);



	/* call the tty release_tty routine to clean out this slot */

release_mem_out:
@@ -1516,7 +1506,7 @@ int tty_init_dev(struct tty_driver *driver, int idx, 
		printk(KERN_INFO "tty_init_dev: ldisc open failed, "

				 "clearing slot %d\n", idx);

	release_tty(tty, idx);

	goto end_init;

	return ERR_PTR(retval);

}



void tty_free_termios(struct tty_struct *tty)
@@ -1925,11 +1915,11 @@ static int __tty_open(struct inode *inode, struct file *filp) 
		return -ENODEV;

	}

got_driver:

	retval = tty_init_dev(driver, index, &tty, 0);

	tty = tty_init_dev(driver, index, 0);

	mutex_unlock(&tty_mutex);

	tty_driver_kref_put(driver);

	if (retval)

		return retval;

	if (IS_ERR(tty))

		return PTR_ERR(tty);



	filp->private_data = tty;

	file_move(filp, &tty->tty_files);

include/linux/tty.h

+2 −2
Original line number Diff line number Diff line
@@ -401,8 +401,8 @@ extern dev_t tty_devnum(struct tty_struct *tty); 
extern void proc_clear_tty(struct task_struct *p);

extern struct tty_struct *get_current_tty(void);

extern void tty_default_fops(struct file_operations *fops);

extern int tty_init_dev(struct tty_driver *driver, int idx,

			struct tty_struct **ret_tty, int first_ok);

extern struct tty_struct *tty_init_dev(struct tty_driver *driver, int idx,

								int first_ok);

extern void tty_release_dev(struct file *filp);



extern struct mutex tty_mutex;