ir241_dongle_locking.diff :
-------------------------
o [CORRECT] Load dongle module with irq disabled in irtty
<Same fix need to go in irport, but irport doesn't work for me>
diff -u -p linux/net/irda/irda_device.d7.c linux/net/irda/irda_device.c
--- linux/net/irda/irda_device.d7.c Tue Aug 6 18:07:18 2002
+++ linux/net/irda/irda_device.c Tue Aug 6 18:08:16 2002
@@ -369,6 +369,12 @@ int irda_task_kick(struct irda_task *tas
* time to complete. We do it this hairy way since we may have been
* called from interrupt context, so it's not possible to use
* schedule_timeout()
+ * Two important notes :
+ * o Make sure you irda_task_delete(task); in case you delete the
+ * calling instance.
+ * o No real need to lock when calling this function, but you may
+ * want to lock within the task handler.
+ * Jean II
*/
struct irda_task *irda_task_execute(void *instance,
IRDA_TASK_CALLBACK function,
@@ -467,6 +473,9 @@ int irda_device_txqueue_empty(struct net
* Function irda_device_init_dongle (self, type, qos)
*
* Initialize attached dongle.
+ *
+ * Important : request_module require us to call this function with
+ * a process context and irq enabled. - Jean II
*/
dongle_t *irda_device_dongle_init(struct net_device *dev, int type)
{
@@ -478,6 +487,7 @@ dongle_t *irda_device_dongle_init(struct
#ifdef CONFIG_KMOD
{
char modname[32];
+ ASSERT(!in_interrupt(), return NULL;);
/* Try to load the module needed */
sprintf(modname, "irda-dongle-%d", type);
request_module(modname);
diff -u -p linux/drivers/net/irda/irtty.d7.c linux/drivers/net/irda/irtty.c
--- linux/drivers/net/irda/irtty.d7.c Tue Aug 6 18:07:57 2002
+++ linux/drivers/net/irda/irtty.c Tue Aug 6 18:08:16 2002
@@ -966,9 +966,14 @@ static int irtty_net_ioctl(struct net_de
IRDA_DEBUG(3, "%s(), %s, (cmd=0x%X)\n", __FUNCTION__, dev->name, cmd);
- /* Disable interrupts & save flags */
- save_flags(flags);
- cli();
+ /* Locking :
+ * irda_device_dongle_init() can't be locked.
+ * irda_task_execute() doesn't need to be locked (but
+ * irtty_change_speed() should protect itself).
+ * As this driver doesn't have spinlock protection, keep
+ * old fashion locking :-(
+ * Jean II
+ */
switch (cmd) {
case SIOCSBANDWIDTH: /* Set bandwidth */
@@ -994,14 +999,17 @@ static int irtty_net_ioctl(struct net_de
dongle->write = irtty_raw_write;
dongle->set_dtr_rts = irtty_set_dtr_rts;
- self->dongle = dongle;
-
- /* Now initialize the dongle! */
+ /* Now initialize the dongle!
+ * Safe to do unlocked : self->dongle is still NULL. */
dongle->issue->open(dongle, &self->qos);
/* Reset dongle */
irda_task_execute(dongle, dongle->issue->reset, NULL, NULL,
NULL);
+
+ /* Make dongle available to driver only now to avoid
+ * race conditions - Jean II */
+ self->dongle = dongle;
break;
case SIOCSMEDIABUSY: /* Set media busy */
if (!capable(CAP_NET_ADMIN))
@@ -1015,20 +1023,26 @@ static int irtty_net_ioctl(struct net_de
case SIOCSDTRRTS:
if (!capable(CAP_NET_ADMIN))
ret = -EPERM;
- else
+ else {
+ save_flags(flags);
+ cli();
irtty_set_dtr_rts(dev, irq->ifr_dtr, irq->ifr_rts);
+ restore_flags(flags);
+ }
break;
case SIOCSMODE:
if (!capable(CAP_NET_ADMIN))
ret = -EPERM;
- else
+ else {
+ save_flags(flags);
+ cli();
irtty_set_mode(dev, irq->ifr_mode);
+ restore_flags(flags);
+ }
break;
default:
ret = -EOPNOTSUPP;
}
-
- restore_flags(flags);
return ret;
}
-
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This archive was generated by hypermail 2b29 : Sat Dec 07 2002 - 22:00:15 EST