Changeset 567807b1 in mainline for generic/src/mm/as.c

Timestamp:

2006-05-24T17:03:29Z (19 years ago)

Author:

Jakub Jermar <jakub@…>

Branches:

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

Children:

8d6bc2d5

Parents:

82da5f5

Message:

Modify the hierarchy of page fault handlers to pass access mode that caused the fault.
Architectures are required to pass either PF_ACCESS_READ, PF_ACCESS_WRITE or PF_ACCESS_EXEC
to as_page_fault(), depending on the cause of the fault.

File:

• generic/src/mm/as.c (modified) (7 diffs)

generic/src/mm/as.c

@@ -376 +376 @@
         __address base;
         ipl_t ipl;
+        bool cond;
 
         ipl = interrupts_disable();
@@ -388 +389 @@
 
         base = area->base;
-        if (!(area->flags & AS_AREA_DEVICE)) {
-                bool cond;      
-        
-                /*
-                 * Releasing physical memory.
-                 * Areas mapping memory-mapped devices are treated differently than
-                 * areas backing frame_alloc()'ed memory.
-                 */
-
-                /*
-                 * Visit only the pages mapped by used_space B+tree.
-                 * Note that we must be very careful when walking the tree
-                 * leaf list and removing used space as the leaf list changes
-                 * unpredictibly after each remove. The solution is to actually
-                 * not walk the tree at all, but to remove items from the head
-                 * of the leaf list until there are some keys left.
-                 */
-                for (cond = true; cond;) {
-                        btree_node_t *node;
+
+        /*
+         * Visit only the pages mapped by used_space B+tree.
+         * Note that we must be very careful when walking the tree
+         * leaf list and removing used space as the leaf list changes
+         * unpredictibly after each remove. The solution is to actually
+         * not walk the tree at all, but to remove items from the head
+         * of the leaf list until there are some keys left.
+         */
+        for (cond = true; cond;) {
+                btree_node_t *node;
                 
-                        ASSERT(!list_empty(&area->used_space.leaf_head));
-                        node = list_get_instance(area->used_space.leaf_head.next, btree_node_t, leaf_link);
-                        if ((cond = (bool) node->keys)) {
-                                __address b = node->key[0];
-                                count_t i;
-                                pte_t *pte;
+                ASSERT(!list_empty(&area->used_space.leaf_head));
+                node = list_get_instance(area->used_space.leaf_head.next, btree_node_t, leaf_link);
+                if ((cond = (bool) node->keys)) {
+                        __address b = node->key[0];
+                        count_t i;
+                        pte_t *pte;
                         
-                                for (i = 0; i < (count_t) node->value[0]; i++) {
-                                        page_table_lock(as, false);
-                                        pte = page_mapping_find(as, b + i*PAGE_SIZE);
-                                        ASSERT(pte && PTE_VALID(pte) && PTE_PRESENT(pte));
-                                        if (area->backend && area->backend->backend_frame_free) {
-                                                area->backend->backend_frame_free(area,
-                                                        b + i*PAGE_SIZE, PTE_GET_FRAME(pte));
-                                        }
-                                        page_mapping_remove(as, b + i*PAGE_SIZE);
-                                        page_table_unlock(as, false);
+                        for (i = 0; i < (count_t) node->value[0]; i++) {
+                                page_table_lock(as, false);
+                                pte = page_mapping_find(as, b + i*PAGE_SIZE);
+                                ASSERT(pte && PTE_VALID(pte) && PTE_PRESENT(pte));
+                                if (area->backend && area->backend->backend_frame_free) {
+                                        area->backend->backend_frame_free(area,
+                                                b + i*PAGE_SIZE, PTE_GET_FRAME(pte));
                                 }
-                                if (!used_space_remove(area, b, i))
-                                        panic("Could not remove used space.\n");
+                                page_mapping_remove(as, b + i*PAGE_SIZE);
+                                page_table_unlock(as, false);
                         }
+                        if (!used_space_remove(area, b, i))
+                                panic("Could not remove used space.\n");
                 }
         }
@@ -624 +616 @@
  *
  * @param page Faulting page.
+ * @param access Access mode that caused the fault (i.e. read/write/exec).
  * @param istate Pointer to interrupted state.
  *
@@ -629 +622 @@
  *         fault was caused by copy_to_uspace() or copy_from_uspace().
  */
-int as_page_fault(__address page, istate_t *istate)
+int as_page_fault(__address page, pf_access_t access, istate_t *istate)
 {
         pte_t *pte;
@@ -689 +682 @@
          * Resort to the backend page fault handler.
          */
-        if (area->backend->backend_page_fault(area, page) != AS_PF_OK) {
+        if (area->backend->backend_page_fault(area, page, access) != AS_PF_OK) {
                 page_table_unlock(AS, false);
                 mutex_unlock(&area->lock);
@@ -1451 +1444 @@
 }
 
-static int anon_page_fault(as_area_t *area, __address addr);
+static int anon_page_fault(as_area_t *area, __address addr, pf_access_t access);
 static void anon_frame_free(as_area_t *area, __address page, __address frame);
 
@@ -1468 +1461 @@
  * @param area Pointer to the address space area.
  * @param addr Faulting virtual address.
+ * @param access Access mode that caused the fault (i.e. read/write/exec).
  *
  * @return AS_PF_FAULT on failure (i.e. page fault) or AS_PF_OK on success (i.e. serviced).
  */
-int anon_page_fault(as_area_t *area, __address addr)
+int anon_page_fault(as_area_t *area, __address addr, pf_access_t access)
 {
         __address frame;