TTY: remove tty_locked

We used it really only serial and ami_serial. The rest of the
callsites were BUG/WARN_ONs to check if BTM is held. Now that we
pruned tty_locked from both of the real users, we can get rid of
tty_lock along with __big_tty_mutex_owner.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Jiri Slaby 2011-07-14 14:35:14 +02:00 committed by Greg Kroah-Hartman
parent eff4b0b9fe
commit 906cbe1364
5 changed files with 2 additions and 21 deletions

View File

@ -1245,8 +1245,6 @@ static void uart_close(struct tty_struct *tty, struct file *filp)
struct uart_port *uport;
unsigned long flags;
BUG_ON(!tty_locked());
if (!state)
return;
@ -1411,7 +1409,6 @@ static void uart_hangup(struct tty_struct *tty)
struct tty_port *port = &state->port;
unsigned long flags;
BUG_ON(!tty_locked());
pr_debug("uart_hangup(%d)\n", state->uart_port->line);
mutex_lock(&port->mutex);
@ -1498,7 +1495,6 @@ static int uart_open(struct tty_struct *tty, struct file *filp)
struct tty_port *port;
int retval, line = tty->index;
BUG_ON(!tty_locked());
pr_debug("uart_open(%d) called\n", line);
/*

View File

@ -450,7 +450,6 @@ static int tty_ldisc_open(struct tty_struct *tty, struct tty_ldisc *ld)
if (ld->ops->open) {
int ret;
/* BTM here locks versus a hangup event */
WARN_ON(!tty_locked());
ret = ld->ops->open(tty);
if (ret)
clear_bit(TTY_LDISC_OPEN, &tty->flags);

View File

@ -15,30 +15,18 @@
* Don't use in new code.
*/
static DEFINE_MUTEX(big_tty_mutex);
struct task_struct *__big_tty_mutex_owner;
EXPORT_SYMBOL_GPL(__big_tty_mutex_owner);
/*
* Getting the big tty mutex.
*/
void __lockfunc tty_lock(void)
{
struct task_struct *task = current;
WARN_ON(__big_tty_mutex_owner == task);
mutex_lock(&big_tty_mutex);
__big_tty_mutex_owner = task;
}
EXPORT_SYMBOL(tty_lock);
void __lockfunc tty_unlock(void)
{
struct task_struct *task = current;
WARN_ON(__big_tty_mutex_owner != task);
__big_tty_mutex_owner = NULL;
mutex_unlock(&big_tty_mutex);
}
EXPORT_SYMBOL(tty_unlock);

View File

@ -301,6 +301,8 @@ int set_selection(const struct tiocl_selection __user *sel, struct tty_struct *t
/* Insert the contents of the selection buffer into the
* queue of the tty associated with the current console.
* Invoked by ioctl().
*
* Locking: always called with BTM from vt_ioctl
*/
int paste_selection(struct tty_struct *tty)
{
@ -310,8 +312,6 @@ int paste_selection(struct tty_struct *tty)
struct tty_ldisc *ld;
DECLARE_WAITQUEUE(wait, current);
/* always called with BTM from vt_ioctl */
WARN_ON(!tty_locked());
console_lock();
poke_blanked_console();

View File

@ -600,8 +600,6 @@ extern long vt_compat_ioctl(struct tty_struct *tty,
/* functions for preparation of BKL removal */
extern void __lockfunc tty_lock(void) __acquires(tty_lock);
extern void __lockfunc tty_unlock(void) __releases(tty_lock);
extern struct task_struct *__big_tty_mutex_owner;
#define tty_locked() (current == __big_tty_mutex_owner)
/*
* wait_event_interruptible_tty -- wait for a condition with the tty lock held