From 9c9f4ded90a59eee84e15f5fd38c03d60184e112 Mon Sep 17 00:00:00 2001 From: Alan Cox Date: Mon, 13 Oct 2008 10:37:26 +0100 Subject: tty: Add a kref count Introduce a kref to the tty structure and use it to protect the tty->signal tty references. For now we don't introduce it for anything else. Signed-off-by: Alan Cox Signed-off-by: Linus Torvalds --- include/linux/tty.h | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) (limited to 'include') diff --git a/include/linux/tty.h b/include/linux/tty.h index e3612c3ac194..b6e6c26883ee 100644 --- a/include/linux/tty.h +++ b/include/linux/tty.h @@ -209,6 +209,7 @@ struct tty_operations; struct tty_struct { int magic; + struct kref kref; struct tty_driver *driver; const struct tty_operations *ops; int index; @@ -311,6 +312,23 @@ extern int kmsg_redirect; extern void console_init(void); extern int vcs_init(void); +/** + * tty_kref_get - get a tty reference + * @tty: tty device + * + * Return a new reference to a tty object. The caller must hold + * sufficient locks/counts to ensure that their existing reference cannot + * go away + */ + +extern inline struct tty_struct *tty_kref_get(struct tty_struct *tty) +{ + if (tty) + kref_get(&tty->kref); + return tty; +} +extern void tty_kref_put(struct tty_struct *tty); + extern int tty_paranoia_check(struct tty_struct *tty, struct inode *inode, const char *routine); extern char *tty_name(struct tty_struct *tty, char *buf); -- cgit v1.2.3