Rework/comment on the userspace interrupt handling

1 files changed, 22 insertions, 27 deletions

diff --git a/linux/dev/arch/i386/kernel/irq.c b/linux/dev/arch/i386/kernel/irq.c
index b7dfa1a..15f95c3 100644
--- a/linux/dev/arch/i386/kernel/irq.c
+++ b/linux/dev/arch/i386/kernel/irq.c
@@ -49,6 +49,7 @@
 
 #include <linux/dev/glue/glue.h>
 #include <machine/machspl.h>
+#include <device/interrupt.h>
 
 #if 0
 /* XXX: This is the way it's done in linux 2.2. GNU Mach currently uses intr_count. It should be made using local_{bh/irq}_count instead (through hardirq_enter/exit) for SMP support. */
@@ -83,7 +84,7 @@ struct linux_action
   void *dev_id;
   struct linux_action *next;
   unsigned long flags;
-  volatile ipc_port_t delivery_port;
+  struct intr_entry *userspace_handler;
 };
 
 static struct linux_action *irq_action[16] =
@@ -117,31 +118,19 @@ linux_intr (int irq)
     {
       // TODO I might need to check whether the interrupt belongs to
       // the current device. But I don't do it for now.
-      if (action->delivery_port)
+      if (action->userspace_handler)
 	{
-	  /* The reference of the port was increased
-	   * when the port was installed.
-	   * If the reference is 1, it means the port should
-	   * have been destroyed and I destroy it now. */
-	  if (action->delivery_port
-	      && action->delivery_port->ip_references == 1)
-	    {
-	      mark_intr_removed (irq, action->delivery_port);
-	      ipc_port_release (action->delivery_port);
-	      *prev = action->next;
-	      printk ("irq handler %d: release an dead delivery port\n", irq);
-	      linux_kfree(action);
-	      action = *prev;
-	      continue;
-	    }
-	  else
-	    {
 	      /* We disable the irq here and it will be enabled
 	       * after the interrupt is handled by the user space driver. */
 	      disable_irq (irq);
-	      queue_intr (irq, action->delivery_port);
-	    }
-
+	      if (! queue_intr (action->userspace_handler))
+		{
+		  *prev = action->next;
+		  linux_kfree(action);
+		  action = *prev;
+		  enable_irq (irq);
+		  continue;
+		}
 	}
       else if (action->handler)
 	action->handler (irq, action->dev_id, &regs);
@@ -285,26 +274,32 @@ setup_x86_irq (int irq, struct linux_action *new)
 
 int
 install_user_intr_handler (unsigned int irq, unsigned long flags,
-			  ipc_port_t dest)
+			   struct intr_entry *entry)
 {
   struct linux_action *action;
+#if 0
   struct linux_action *old;
+#endif
   int retval;
 
   assert (irq < 16);
 
-  /* Test whether the irq handler has been set */
+#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 == dest)
+      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()' ?
@@ -319,7 +314,7 @@ install_user_intr_handler (unsigned int irq, unsigned long flags,
   action->next = NULL;
   action->dev_id = NULL;
   action->flags = flags;
-  action->delivery_port = dest;
+  action->userspace_handler = entry;
   
   retval = setup_x86_irq (irq, action);
   if (retval)
@@ -356,7 +351,7 @@ request_irq (unsigned int irq, void (*handler) (int, void *, struct pt_regs *),
   action->next = NULL;
   action->dev_id = dev_id;
   action->flags = flags;
-  action->delivery_port = NULL;
+  action->userspace_handler = NULL;
   
   retval = setup_x86_irq (irq, action);
   if (retval)