Commit ef06b192 authored by Jean Tourrilhes's avatar Jean Tourrilhes Committed by David S. Miller

[IRDA]: Fix locking in the ircomm-shutdown path.

parent cdd56702
......@@ -52,6 +52,11 @@
/* Same for payload size. See qos.c for the smallest max data size */
#define IRCOMM_TTY_DATA_UNINITIALISED (64 - IRCOMM_TTY_HDR_UNINITIALISED)
/* Those are really defined in include/linux/serial.h - Jean II */
#define ASYNC_B_INITIALIZED 31 /* Serial port was initialized */
#define ASYNC_B_NORMAL_ACTIVE 29 /* Normal device is active */
#define ASYNC_B_CLOSING 27 /* Serial port is closing */
/*
* IrCOMM TTY driver state
*/
......@@ -75,7 +80,7 @@ struct ircomm_tty_cb {
LOCAL_FLOW flow; /* IrTTP flow status */
int line;
__u32 flags;
volatile unsigned long flags;
__u8 dlsap_sel;
__u8 slsap_sel;
......
......@@ -181,15 +181,15 @@ void __exit ircomm_tty_cleanup(void)
static int ircomm_tty_startup(struct ircomm_tty_cb *self)
{
notify_t notify;
int ret;
int ret = -ENODEV;
IRDA_DEBUG(2, "%s()\n", __FUNCTION__ );
ASSERT(self != NULL, return -1;);
ASSERT(self->magic == IRCOMM_TTY_MAGIC, return -1;);
/* Already open */
if (self->flags & ASYNC_INITIALIZED) {
/* Check if already open */
if (test_and_set_bit(ASYNC_B_INITIALIZED, &self->flags)) {
IRDA_DEBUG(2, "%s(), already open so break out!\n", __FUNCTION__ );
return 0;
}
......@@ -213,7 +213,7 @@ static int ircomm_tty_startup(struct ircomm_tty_cb *self)
self->line);
}
if (!self->ircomm)
return -ENODEV;
goto err;
self->slsap_sel = self->ircomm->slsap_sel;
......@@ -221,12 +221,13 @@ static int ircomm_tty_startup(struct ircomm_tty_cb *self)
ret = ircomm_tty_attach_cable(self);
if (ret < 0) {
ERROR("%s(), error attaching cable!\n", __FUNCTION__);
return ret;
goto err;
}
self->flags |= ASYNC_INITIALIZED;
return 0;
err:
clear_bit(ASYNC_B_INITIALIZED, &self->flags);
return ret;
}
/*
......@@ -299,7 +300,8 @@ static int ircomm_tty_block_til_ready(struct ircomm_tty_cb *self,
current->state = TASK_INTERRUPTIBLE;
if (tty_hung_up_p(filp) || !(self->flags & ASYNC_INITIALIZED)){
if (tty_hung_up_p(filp) ||
!test_bit(ASYNC_B_INITIALIZED, &self->flags)) {
retval = (self->flags & ASYNC_HUP_NOTIFY) ?
-EAGAIN : -ERESTARTSYS;
break;
......@@ -310,7 +312,7 @@ static int ircomm_tty_block_til_ready(struct ircomm_tty_cb *self,
* specified, we cannot return before the IrCOMM link is
* ready
*/
if (!(self->flags & ASYNC_CLOSING) &&
if (!test_bit(ASYNC_B_CLOSING, &self->flags) &&
(do_clocal || (self->settings.dce & IRCOMM_CD)) &&
self->state == IRCOMM_TTY_READY)
{
......@@ -425,7 +427,7 @@ static int ircomm_tty_open(struct tty_struct *tty, struct file *filp)
* If the port is the middle of closing, bail out now
*/
if (tty_hung_up_p(filp) ||
(self->flags & ASYNC_CLOSING)) {
test_bit(ASYNC_B_CLOSING, &self->flags)) {
/* Hm, why are we blocking on ASYNC_CLOSING if we
* do return -EAGAIN/-ERESTARTSYS below anyway?
......@@ -435,7 +437,7 @@ static int ircomm_tty_open(struct tty_struct *tty, struct file *filp)
* probably better sleep uninterruptible?
*/
if (wait_event_interruptible(self->close_wait, !(self->flags&ASYNC_CLOSING))) {
if (wait_event_interruptible(self->close_wait, !test_bit(ASYNC_B_CLOSING, &self->flags))) {
WARNING("%s - got signal while blocking on ASYNC_CLOSING!\n",
__FUNCTION__);
return -ERESTARTSYS;
......@@ -530,11 +532,13 @@ static void ircomm_tty_close(struct tty_struct *tty, struct file *filp)
IRDA_DEBUG(0, "%s(), open count > 0\n", __FUNCTION__ );
return;
}
self->flags |= ASYNC_CLOSING;
/* Hum... Should be test_and_set_bit ??? - Jean II */
set_bit(ASYNC_B_CLOSING, &self->flags);
/* We need to unlock here (we were unlocking at the end of this
* function), because tty_wait_until_sent() may schedule.
* I don't know if the rest should be locked somehow,
* I don't know if the rest should be protected somehow,
* so someone should check. - Jean II */
spin_unlock_irqrestore(&self->spinlock, flags);
......@@ -979,9 +983,11 @@ static void ircomm_tty_shutdown(struct ircomm_tty_cb *self)
IRDA_DEBUG(0, "%s()\n", __FUNCTION__ );
if (!(self->flags & ASYNC_INITIALIZED))
if (!test_and_clear_bit(ASYNC_B_INITIALIZED, &self->flags))
return;
ircomm_tty_detach_cable(self);
spin_lock_irqsave(&self->spinlock, flags);
del_timer(&self->watchdog_timer);
......@@ -998,13 +1004,10 @@ static void ircomm_tty_shutdown(struct ircomm_tty_cb *self)
self->tx_skb = NULL;
}
ircomm_tty_detach_cable(self);
if (self->ircomm) {
ircomm_close(self->ircomm);
self->ircomm = NULL;
}
self->flags &= ~ASYNC_INITIALIZED;
spin_unlock_irqrestore(&self->spinlock, flags);
}
......
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