Commit 9ed90d20 authored by Rob Herring's avatar Rob Herring Committed by Greg Kroah-Hartman
Browse files

tty: move the non-file related parts of tty_release to new tty_release_struct 



For in-kernel tty users, we need to be able to create and destroy
'struct tty' that are not associated with a file. The creation side is
fine, but tty_release() needs to be split into the file handle portion
and the struct tty portion. Introduce a new function, tty_release_struct,
to handle just the destroying of a struct tty.

Signed-off-by: default avatarRob Herring <robh@kernel.org>
Reviewed-by: default avatarAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-By: default avatarSebastian Reichel <sre@kernel.org>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 2cc32b18

drivers/tty/tty_io.c

+32 −18
Original line number Diff line number Diff line
@@ -1744,6 +1744,37 @@ static int tty_release_checks(struct tty_struct *tty, int idx) 
	return 0;

}



/**

 *	tty_release_struct	-	release a tty struct

 *	@tty: tty device

 *	@idx: index of the tty

 *

 *	Performs the final steps to release and free a tty device. It is

 *	roughly the reverse of tty_init_dev.

 */

void tty_release_struct(struct tty_struct *tty, int idx)

{

	/*

	 * Ask the line discipline code to release its structures

	 */

	tty_ldisc_release(tty);



	/* Wait for pending work before tty destruction commmences */

	tty_flush_works(tty);



	tty_debug_hangup(tty, "freeing structure\n");

	/*

	 * The release_tty function takes care of the details of clearing

	 * the slots and preserving the termios structure. The tty_unlock_pair

	 * should be safe as we keep a kref while the tty is locked (so the

	 * unlock never unlocks a freed tty).

	 */

	mutex_lock(&tty_mutex);

	release_tty(tty, idx);

	mutex_unlock(&tty_mutex);

}

EXPORT_SYMBOL_GPL(tty_release_struct);



/**

 *	tty_release		-	vfs callback for close

 *	@inode: inode of tty
@@ -1898,25 +1929,8 @@ int tty_release(struct inode *inode, struct file *filp) 
		return 0;



	tty_debug_hangup(tty, "final close\n");

	/*

	 * Ask the line discipline code to release its structures

	 */

	tty_ldisc_release(tty);



	/* Wait for pending work before tty destruction commmences */

	tty_flush_works(tty);



	tty_debug_hangup(tty, "freeing structure\n");

	/*

	 * The release_tty function takes care of the details of clearing

	 * the slots and preserving the termios structure. The tty_unlock_pair

	 * should be safe as we keep a kref while the tty is locked (so the

	 * unlock never unlocks a freed tty).

	 */

	mutex_lock(&tty_mutex);

	release_tty(tty, idx);

	mutex_unlock(&tty_mutex);



	tty_release_struct(tty, idx);

	return 0;

}

include/linux/tty.h

+1 −0
Original line number Diff line number Diff line
@@ -528,6 +528,7 @@ extern int tty_alloc_file(struct file *file); 
extern void tty_add_file(struct tty_struct *tty, struct file *file);

extern void tty_free_file(struct file *file);

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

extern void tty_release_struct(struct tty_struct *tty, int idx);

extern int tty_release(struct inode *inode, struct file *filp);

extern void tty_init_termios(struct tty_struct *tty);

extern int tty_standard_install(struct tty_driver *driver,