Kernel interrupt hook management fixes:

- properly assign unique hook IDs
- after hook removal, remove hook-specific interrupt disable flag

diff --git a/kernel/interrupt.c b/kernel/interrupt.c
index 3dffb72b6b7e3a848fba8e20a1191da8529d8233..dde390d1b2163802489f3c4e6af750e034542771 100644 (file)
--- a/kernel/interrupt.c
+++ b/kernel/interrupt.c
@@ -28,22 +28,27 @@ PUBLIC void put_irq_handler( irq_hook_t* hook, int irq, irq_handler_t handler)
 {
   int id;
   irq_hook_t **line;
+  unsigned long bitmap;
   
   if( irq < 0 || irq >= NR_IRQ_VECTORS )
        minix_panic("invalid call to put_irq_handler", irq);
 
   line = &irq_handlers[irq];
-  id = 1;
-  
+
+  bitmap = 0;
   while ( *line != NULL ) {
        if(hook == *line) return; /* extra initialization */
+       bitmap |= (*line)->id;  /* mark ids in use */
        line = &(*line)->next;
-       id <<= 1;                 /* max 32 hooks for one line. */
   }
-  
-  if(id == 0)
-       minix_panic("Too many handlers for irq", irq);
 
+  /* find the lowest id not in use */
+  for (id = 1; id != 0; id <<= 1)
+       if (!(bitmap & id)) break;
+
+  if(id == 0)
+       minix_panic("Too many handlers for irq", irq);
+  
   hook->next = NULL;
   hook->handler = handler;
   hook->irq = irq;
@@ -81,6 +86,8 @@ PUBLIC void rm_irq_handler( irq_hook_t* hook ) {
                (*line) = (*line)->next;      
                if(!irq_handlers[irq])
                        irq_use &= ~(1 << irq);
+               if (irq_actids[irq] & id)
+                       irq_actids[irq] &= ~id;
                return;
        }          
        line = &(*line)->next;