Changeset 5a7d9d1 in mainline for generic/src/mm/as.c

Timestamp:

2006-03-17T10:07:28Z (19 years ago)

Author:

Jakub Jermar <jakub@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

4e49572

Parents:

226a654

Message:

More checks for address space area conflicts.

File:

• generic/src/mm/as.c (modified) (3 diffs)

generic/src/mm/as.c

@@ -52 +52 @@
 #include <debug.h>
 #include <memstr.h>
+#include <macros.h>
 #include <arch.h>
 #include <print.h>
@@ -538 +539 @@
         as_area_t *a;
         
+        /*
+         * We don't want any area to have conflicts with NULL page.
+         */
+        if (overlaps(va, size, NULL, PAGE_SIZE))
+                return false;
+        
         for (cur = as->as_area_head.next; cur != &as->as_area_head; cur = cur->next) {
-                __address start;
-                __address end;
+                __address a_start;
+                size_t a_size;
         
                 a = list_get_instance(cur, as_area_t, link);
@@ -548 +555 @@
                 spinlock_lock(&a->lock);
 
-                start = a->base;
-                end = a->base + a->pages * PAGE_SIZE - 1;
+                a_start = a->base;
+                a_size = a->pages * PAGE_SIZE;
 
                 spinlock_unlock(&a->lock);
 
-                if ((va >= start) && (va <= end)) {
-                        /*
-                         * Tested area is inside another area.
-                         */
-                        return false;
-                }
-                
-                if ((start >= va) && (start < va + size)) {
-                        /*
-                         * Another area starts in tested area.
-                         */
-                        return false;
-                }
-                
-                if ((end >= va) && (end < va + size)) {
-                        /*
-                         * Another area ends in tested area.
-                         */
-                        return false;
-                }
-
+                if (overlaps(va, size, a_start, a_size))
+                        return false;           
+
+        }
+
+        /*
+         * So far, the area does not conflict with other areas.
+         * Check if it doesn't conflict with kernel address space.
+         */      
+        if (!KERNEL_ADDRESS_SPACE_SHADOWED) {
+                return !overlaps(va, size, 
+                        KERNEL_ADDRESS_SPACE_START, KERNEL_ADDRESS_SPACE_END-KERNEL_ADDRESS_SPACE_START);
         }