Changes in kernel/generic/src/mm/as.c [d99c1d2:1624aae] in mainline

File:

• kernel/generic/src/mm/as.c (modified) (5 diffs)

kernel/generic/src/mm/as.c

@@ -1 +1 @@
 /*
- * Copyright (c) 2001-2006 Jakub Jermar
+ * Copyright (c) 2010 Jakub Jermar
  * All rights reserved.
  *
@@ -152 +152 @@
          * reference count never drops to zero.
          */
-        atomic_set(&AS_KERNEL->refcount, 1);
+        as_hold(AS_KERNEL);
 }
 
@@ -200 +200 @@
         DEADLOCK_PROBE_INIT(p_asidlock);
 
+        ASSERT(as != AS);
         ASSERT(atomic_get(&as->refcount) == 0);
         
         /*
-         * Since there is no reference to this area,
-         * it is safe not to lock its mutex.
+         * Since there is no reference to this address space, it is safe not to
+         * lock its mutex.
          */
 
@@ -225 +226 @@
         preemption_enable();    /* Interrupts disabled, enable preemption */
         if (as->asid != ASID_INVALID && as != AS_KERNEL) {
-                if (as != AS && as->cpu_refcount == 0)
+                if (as->cpu_refcount == 0)
                         list_remove(&as->inactive_as_with_asid_link);
                 asid_put(as->asid);
@@ -258 +259 @@
 
         slab_free(as_slab, as);
+}
+
+/** Hold a reference to an address space.
+ *
+ * Holding a reference to an address space prevents destruction of that address
+ * space.
+ *
+ * @param a             Address space to be held.
+ */
+void as_hold(as_t *as)
+{
+        atomic_inc(&as->refcount);
+}
+
+/** Release a reference to an address space.
+ *
+ * The last one to release a reference to an address space destroys the address
+ * space.
+ *
+ * @param a             Address space to be released.
+ */
+void as_release(as_t *as)
+{
+        if (atomic_predec(&as->refcount) == 0)
+                as_destroy(as);
 }