Remove bind_evtchn_to_irq/unbind_evtchn_from_irq from the

evtchn kernel interface. Fix error path in bind_evtchn_to_irqhandler.
Fix backend drivers to avoid double freeing IRQs.

Signed-off-by: Keir Fraser <keir@xensource.com>

5 files changed, 25 insertions, 28 deletions

diff --git a/linux-2.6-xen-sparse/arch/ia64/xen/drivers/evtchn_ia64.c b/linux-2.6-xen-sparse/arch/ia64/xen/drivers/evtchn_ia64.c
index e5c3a50f78..f6e6c9ee72 100644
--- a/linux-2.6-xen-sparse/arch/ia64/xen/drivers/evtchn_ia64.c
+++ b/linux-2.6-xen-sparse/arch/ia64/xen/drivers/evtchn_ia64.c
@@ -67,12 +67,6 @@ void unbind_evtchn_from_irqhandler(unsigned int evtchn, void *dev_id)
     evtchns[evtchn].handler = NULL;
 }
 
-void unbind_evtchn_from_irq(unsigned int evtchn)
-{
-	printk("unbind_evtchn_from_irq called... FIXME??\n");
-	while(1);
-}
-
 irqreturn_t evtchn_interrupt(int irq, void *dev_id, struct pt_regs *regs)
 {
     u32            l1, l2;
diff --git a/linux-2.6-xen-sparse/arch/xen/kernel/evtchn.c b/linux-2.6-xen-sparse/arch/xen/kernel/evtchn.c
index a709dd4198..6a85441f7f 100644
--- a/linux-2.6-xen-sparse/arch/xen/kernel/evtchn.c
+++ b/linux-2.6-xen-sparse/arch/xen/kernel/evtchn.c
@@ -296,7 +296,7 @@ void unbind_ipi_from_irq(int ipi)
 }
 EXPORT_SYMBOL(unbind_ipi_from_irq);
 
-int bind_evtchn_to_irq(unsigned int evtchn)
+static int bind_evtchn_to_irq(unsigned int evtchn)
 {
 	int irq;
 
@@ -314,9 +314,8 @@ int bind_evtchn_to_irq(unsigned int evtchn)
     
 	return irq;
 }
-EXPORT_SYMBOL(bind_evtchn_to_irq);
 
-void unbind_evtchn_from_irq(unsigned int irq)
+static void unbind_evtchn_from_irq(unsigned int irq)
 {
 	evtchn_op_t op = { .cmd = EVTCHNOP_close };
 	int evtchn = irq_to_evtchn[irq];
@@ -333,7 +332,6 @@ void unbind_evtchn_from_irq(unsigned int irq)
 
 	spin_unlock(&irq_mapping_update_lock);
 }
-EXPORT_SYMBOL(unbind_evtchn_from_irq);
 
 int bind_evtchn_to_irqhandler(
 	unsigned int evtchn,
@@ -347,8 +345,10 @@ int bind_evtchn_to_irqhandler(
 
 	irq = bind_evtchn_to_irq(evtchn);
 	retval = request_irq(irq, handler, irqflags, devname, dev_id);
-	if (retval != 0)
+	if (retval != 0) {
 		unbind_evtchn_from_irq(irq);
+		return retval;
+	}
 
 	return irq;
 }
diff --git a/linux-2.6-xen-sparse/drivers/xen/blkback/interface.c b/linux-2.6-xen-sparse/drivers/xen/blkback/interface.c
index 458d6e9c36..ee1889a09a 100644
--- a/linux-2.6-xen-sparse/drivers/xen/blkback/interface.c
+++ b/linux-2.6-xen-sparse/drivers/xen/blkback/interface.c
@@ -74,6 +74,10 @@ int blkif_map(blkif_t *blkif, unsigned long shared_page, unsigned int evtchn)
 		.u.bind_interdomain.remote_dom = blkif->domid,
 		.u.bind_interdomain.remote_port = evtchn };
 
+	/* Already connected through? */
+	if (blkif->irq)
+		return 0;
+
 	if ( (blkif->blk_ring_area = alloc_vm_area(PAGE_SIZE)) == NULL )
 		return -ENOMEM;
 
@@ -107,8 +111,12 @@ static void free_blkif(void *arg)
 {
 	blkif_t *blkif = (blkif_t *)arg;
 
-	if (blkif->irq)
-		unbind_evtchn_from_irqhandler(blkif->irq, blkif);
+	/* Already disconnected? */
+	if (!blkif->irq)
+		return;
+
+	unbind_evtchn_from_irqhandler(blkif->irq, blkif);
+	blkif->irq = 0;
 
 	vbd_free(&blkif->vbd);
 
diff --git a/linux-2.6-xen-sparse/drivers/xen/netback/interface.c b/linux-2.6-xen-sparse/drivers/xen/netback/interface.c
index 3e4537c90f..43f516badf 100644
--- a/linux-2.6-xen-sparse/drivers/xen/netback/interface.c
+++ b/linux-2.6-xen-sparse/drivers/xen/netback/interface.c
@@ -183,6 +183,10 @@ int netif_map(netif_t *netif, unsigned long tx_ring_ref,
 		.u.bind_interdomain.remote_dom = netif->domid,
 		.u.bind_interdomain.remote_port = evtchn };
 
+	/* Already connected through? */
+	if (netif->irq)
+		return 0;
+
 	netif->comms_area = alloc_vm_area(2*PAGE_SIZE);
 	if (netif->comms_area == NULL)
 		return -ENOMEM;
@@ -227,13 +231,12 @@ static void free_netif_callback(void *arg)
 {
 	netif_t *netif = (netif_t *)arg;
 
-	/*
-	 * This can't be done in netif_disconnect() because at that point
-	 * there may be outstanding requests in the network stack whose
-	 * asynchronous responses must still be notified to the remote driver.
-	 */
-	if (netif->irq)
-		unbind_evtchn_from_irqhandler(netif->irq, netif);
+	/* Already disconnected? */
+	if (!netif->irq)
+		return;
+
+	unbind_evtchn_from_irqhandler(netif->irq, netif);
+	netif->irq = 0;
 
 	unregister_netdev(netif->dev);
 
diff --git a/linux-2.6-xen-sparse/include/asm-xen/evtchn.h b/linux-2.6-xen-sparse/include/asm-xen/evtchn.h
index c9feb34606..a38b8732a1 100644
--- a/linux-2.6-xen-sparse/include/asm-xen/evtchn.h
+++ b/linux-2.6-xen-sparse/include/asm-xen/evtchn.h
@@ -52,14 +52,6 @@ extern int  bind_ipi_to_irq(int ipi);
 extern void unbind_ipi_from_irq(int ipi);
 
 /*
- * Dynamically bind an event-channel port to Linux IRQ space.
- * BIND:   Returns IRQ or error.
- * UNBIND: Takes IRQ to unbind from; automatically closes the event channel.
- */
-extern int  bind_evtchn_to_irq(unsigned int evtchn);
-extern void unbind_evtchn_from_irq(unsigned int irq);
-
-/*
  * Dynamically bind an event-channel port to an IRQ-like callback handler.
  * On some platforms this may not be implemented via the Linux IRQ subsystem.
  * The IRQ argument passed to the callback handler is the same as returned