No need for a new kind of notification, we can provide a smoother upgrade path

1 files changed, 20 insertions, 30 deletions

diff --git a/linux/dev/arch/i386/kernel/irq.c b/linux/dev/arch/i386/kernel/irq.c
index 15f95c3..e2c18c7 100644
--- a/linux/dev/arch/i386/kernel/irq.c
+++ b/linux/dev/arch/i386/kernel/irq.c
@@ -104,7 +104,6 @@ linux_intr (int irq)
 {
   struct pt_regs regs;
   struct linux_action *action = *(irq_action + irq);
-  struct linux_action **prev = &irq_action[irq];
   unsigned long flags;
 
   kstat.interrupts[irq]++;
@@ -123,18 +122,10 @@ linux_intr (int irq)
 	      /* We disable the irq here and it will be enabled
 	       * after the interrupt is handled by the user space driver. */
 	      disable_irq (irq);
-	      if (! queue_intr (action->userspace_handler))
-		{
-		  *prev = action->next;
-		  linux_kfree(action);
-		  action = *prev;
-		  enable_irq (irq);
-		  continue;
-		}
+	      queue_intr (action->userspace_handler);
 	}
       else if (action->handler)
 	action->handler (irq, action->dev_id, &regs);
-      prev = &action->next;
       action = action->next;
     }
 
@@ -277,30 +268,10 @@ install_user_intr_handler (unsigned int irq, unsigned long flags,
 			   struct intr_entry *entry)
 {
   struct linux_action *action;
-#if 0
-  struct linux_action *old;
-#endif
   int retval;
 
   assert (irq < 16);
 
-#if 0
-  /* Test whether the irq handler has already been set.  */
-  /* JW: Actually, that cannot happen.  We test for that in
-     device_intr_register before calling this function.  */
-  // TODO I need to protect the array when iterating it.
-  old = irq_action[irq];
-  while (old)
-    {
-      if (old->delivery_port == entry->dest)
-	{
-	  printk ("The interrupt handler has been installed on line %d", irq);
-	  return linux_to_mach_error (-EAGAIN);
-	}
-      old = old->next;
-    }
-#endif
-
   /*
    * Hmm... Should I use `kalloc()' ?
    * By OKUJI Yoshinori.
@@ -323,6 +294,25 @@ install_user_intr_handler (unsigned int irq, unsigned long flags,
   return linux_to_mach_error (retval);
 }
 
+int
+remove_user_intr_handler (unsigned int irq, struct intr_entry *entry)
+{
+  struct linux_action *action, **prev;
+
+  for (prev = &irq_action[irq], action = irq_action[irq];
+       action;
+       prev = &action->next, action = action->next)
+    if (action->userspace_handler == entry)
+      {
+	*prev = action->next;
+	linux_kfree(action);
+	enable_irq (irq);
+	return 1;
+      }
+
+  return 0;
+}
+
 /*
  * Attach a handler to an IRQ.
  */