Changeset 03523dc in mainline for kernel/generic/src/mm/backend_anon.c

Timestamp:

2011-01-15T16:12:46Z (13 years ago)

Author:

Jakub Jermar <jakub@…>

Branches:

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

Children:

6b9e85b

Parents:

630a8ef

Message:

Add more hooks to address space area backends so that each backend can
take action also on:

• as_area_create()
• as_area_resize()
• as_area_destroy()

Add basic memory reservation code to anonymous and elf address space
area backends.

File:

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

kernel/generic/src/mm/backend_anon.c

@@ -39 +39 @@
 #include <mm/as.h>
 #include <mm/page.h>
+#include <mm/reserve.h>
 #include <genarch/mm/page_pt.h>
 #include <genarch/mm/page_ht.h>
@@ -55 +56 @@
 #endif
 
+static bool anon_create(as_area_t *);
+static bool anon_resize(as_area_t *, size_t);
+static void anon_share(as_area_t *area);
+static void anon_destroy(as_area_t *);
+
 static int anon_page_fault(as_area_t *area, uintptr_t addr, pf_access_t access);
 static void anon_frame_free(as_area_t *area, uintptr_t page, uintptr_t frame);
-static void anon_share(as_area_t *area);
 
 mem_backend_t anon_backend = {
+        .create = anon_create,
+        .resize = anon_resize,
+        .share = anon_share,
+        .destroy = anon_destroy,
+
         .page_fault = anon_page_fault,
         .frame_free = anon_frame_free,
-        .share = anon_share
 };
+
+bool anon_create(as_area_t *area)
+{
+        return reserve_try_alloc(area->pages);
+}
+
+bool anon_resize(as_area_t *area, size_t new_pages)
+{
+        /**
+         * @todo
+         * Reserve also space needed for the supporting strutures allocated
+         * during page fault.
+         */
+
+        if (new_pages > area->pages)
+                return reserve_try_alloc(new_pages - area->pages);
+        else if (new_pages < area->pages)
+                reserve_free(area->pages - new_pages);
+
+        return true;
+}
+
+/** Share the anonymous address space area.
+ *
+ * Sharing of anonymous area is done by duplicating its entire mapping
+ * to the pagemap. Page faults will primarily search for frames there.
+ *
+ * The address space and address space area must be already locked.
+ *
+ * @param area Address space area to be shared.
+ */
+void anon_share(as_area_t *area)
+{
+        link_t *cur;
+
+        ASSERT(mutex_locked(&area->as->lock));
+        ASSERT(mutex_locked(&area->lock));
+
+        /*
+         * Copy used portions of the area to sh_info's page map.
+         */
+        mutex_lock(&area->sh_info->lock);
+        for (cur = area->used_space.leaf_head.next;
+            cur != &area->used_space.leaf_head; cur = cur->next) {
+                btree_node_t *node;
+                unsigned int i;
+                
+                node = list_get_instance(cur, btree_node_t, leaf_link);
+                for (i = 0; i < node->keys; i++) {
+                        uintptr_t base = node->key[i];
+                        size_t count = (size_t) node->value[i];
+                        unsigned int j;
+                        
+                        for (j = 0; j < count; j++) {
+                                pte_t *pte;
+                        
+                                page_table_lock(area->as, false);
+                                pte = page_mapping_find(area->as,
+                                    base + j * PAGE_SIZE);
+                                ASSERT(pte && PTE_VALID(pte) &&
+                                    PTE_PRESENT(pte));
+                                btree_insert(&area->sh_info->pagemap,
+                                    (base + j * PAGE_SIZE) - area->base,
+                                    (void *) PTE_GET_FRAME(pte), NULL);
+                                page_table_unlock(area->as, false);
+
+                                pfn_t pfn = ADDR2PFN(PTE_GET_FRAME(pte));
+                                frame_reference_add(pfn);
+                        }
+
+                }
+        }
+        mutex_unlock(&area->sh_info->lock);
+}
+
+void anon_destroy(as_area_t *area)
+{
+        reserve_free(area->pages);
+}
+
 
 /** Service a page fault in the anonymous memory address space area.
@@ -178 +267 @@
 }
 
-/** Share the anonymous address space area.
- *
- * Sharing of anonymous area is done by duplicating its entire mapping
- * to the pagemap. Page faults will primarily search for frames there.
- *
- * The address space and address space area must be already locked.
- *
- * @param area Address space area to be shared.
- */
-void anon_share(as_area_t *area)
-{
-        link_t *cur;
-
-        ASSERT(mutex_locked(&area->as->lock));
-        ASSERT(mutex_locked(&area->lock));
-
-        /*
-         * Copy used portions of the area to sh_info's page map.
-         */
-        mutex_lock(&area->sh_info->lock);
-        for (cur = area->used_space.leaf_head.next;
-            cur != &area->used_space.leaf_head; cur = cur->next) {
-                btree_node_t *node;
-                unsigned int i;
-                
-                node = list_get_instance(cur, btree_node_t, leaf_link);
-                for (i = 0; i < node->keys; i++) {
-                        uintptr_t base = node->key[i];
-                        size_t count = (size_t) node->value[i];
-                        unsigned int j;
-                        
-                        for (j = 0; j < count; j++) {
-                                pte_t *pte;
-                        
-                                page_table_lock(area->as, false);
-                                pte = page_mapping_find(area->as,
-                                    base + j * PAGE_SIZE);
-                                ASSERT(pte && PTE_VALID(pte) &&
-                                    PTE_PRESENT(pte));
-                                btree_insert(&area->sh_info->pagemap,
-                                    (base + j * PAGE_SIZE) - area->base,
-                                    (void *) PTE_GET_FRAME(pte), NULL);
-                                page_table_unlock(area->as, false);
-
-                                pfn_t pfn = ADDR2PFN(PTE_GET_FRAME(pte));
-                                frame_reference_add(pfn);
-                        }
-
-                }
-        }
-        mutex_unlock(&area->sh_info->lock);
-}
-
 /** @}
  */