TTY: hvc_console, add tty install

This has two outcomes:
* we give the TTY layer a tty_port
* we do not find the info structure every time open is called on that
  tty

Since we take a reference to a port in ->install, we need also
->cleanup to drop that reference.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: linuxppc-dev@lists.ozlabs.org
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Jiri Slaby 2012-08-07 21:48:04 +02:00 committed by Greg Kroah-Hartman
parent 20cda6f25f
commit bdb498c200

View file

@ -299,20 +299,33 @@ static void hvc_unthrottle(struct tty_struct *tty)
hvc_kick();
}
static int hvc_install(struct tty_driver *driver, struct tty_struct *tty)
{
struct hvc_struct *hp;
int rc;
/* Auto increments kref reference if found. */
if (!(hp = hvc_get_by_index(tty->index)))
return -ENODEV;
tty->driver_data = hp;
rc = tty_port_install(&hp->port, driver, tty);
if (rc)
tty_port_put(&hp->port);
return rc;
}
/*
* The TTY interface won't be used until after the vio layer has exposed the vty
* adapter to the kernel.
*/
static int hvc_open(struct tty_struct *tty, struct file * filp)
{
struct hvc_struct *hp;
struct hvc_struct *hp = tty->driver_data;
unsigned long flags;
int rc = 0;
/* Auto increments kref reference if found. */
if (!(hp = hvc_get_by_index(tty->index)))
return -ENODEV;
spin_lock_irqsave(&hp->port.lock, flags);
/* Check and then increment for fast path open. */
if (hp->port.count++ > 0) {
@ -322,7 +335,6 @@ static int hvc_open(struct tty_struct *tty, struct file * filp)
} /* else count == 0 */
spin_unlock_irqrestore(&hp->port.lock, flags);
tty->driver_data = hp;
tty_port_tty_set(&hp->port, tty);
if (hp->ops->notifier_add)
@ -389,6 +401,11 @@ static void hvc_close(struct tty_struct *tty, struct file * filp)
hp->vtermno, hp->port.count);
spin_unlock_irqrestore(&hp->port.lock, flags);
}
}
static void hvc_cleanup(struct tty_struct *tty)
{
struct hvc_struct *hp = tty->driver_data;
tty_port_put(&hp->port);
}
@ -792,8 +809,10 @@ static void hvc_poll_put_char(struct tty_driver *driver, int line, char ch)
#endif
static const struct tty_operations hvc_ops = {
.install = hvc_install,
.open = hvc_open,
.close = hvc_close,
.cleanup = hvc_cleanup,
.write = hvc_write,
.hangup = hvc_hangup,
.unthrottle = hvc_unthrottle,