actually, it didn't work, but does nowbasic_paging

5 files changed, 83 insertions, 17 deletions

diff --git a/kern/kernel.c b/kern/kernel.c
index 2752aaa4..e5238368 100644
--- a/kern/kernel.c
+++ b/kern/kernel.c
@@ -34,27 +34,41 @@
 #include <vm/vm_object.h>
 #include <vm/vm_prot.h>
 
-#define OBJ_SIZE (PAGE_SIZE * 10)
+#define OBJ_SIZE (PAGE_SIZE * 4)
 
 static void
-kernel_test(void *arg)
+kernel_test_fault(void *arg)
 {
     struct vm_object *object;
+    struct vm_map *map;
     unsigned long addr;
     int error, flags;
 
     (void)arg;
 
+    map = thread_self()->task->map;
+
     object = vm_anon_create(OBJ_SIZE);
     assert(object != NULL);
     addr = 0;
     flags = VM_MAP_FLAGS(VM_PROT_ALL, VM_PROT_ALL, VM_INHERIT_DEFAULT,
                          VM_ADV_DEFAULT, 0);
-    error = vm_map_enter(kernel_map, object, 0, &addr, OBJ_SIZE, 0, flags);
+    error = vm_map_enter(map, object, 0, &addr, OBJ_SIZE, 0, flags);
     assert(!error);
     printk("anonymous object mapped at %#lx\n", addr);
-    vm_map_info(kernel_map);
-    memset((void *)addr, '\0', OBJ_SIZE);
+    vm_map_info(map);
+    printk("filling object\n");
+    memset((void *)addr, 0xff, OBJ_SIZE);
+    printk("object filled\n");
+    printk("removing physical mappings\n");
+
+    /* TODO pmap_remove() */
+    pmap_kremove(addr, addr + OBJ_SIZE);
+    pmap_update(kernel_pmap, addr, addr + OBJ_SIZE);
+
+    printk("filling object again\n");
+    memset((void *)addr, 0xff, OBJ_SIZE);
+    printk("object filled\n");
 }
 
 static void
@@ -62,14 +76,18 @@ start_test(void)
 {
     struct thread_attr attr;
     struct thread *thread;
+    struct task *task;
     int error;
 
-    attr.name = "test";
+    error = task_create(&task, "test_fault");
+    assert(!error);
+
+    attr.name = "test_fault";
     attr.cpumap = NULL;
-    attr.task = NULL;
+    attr.task = task;
     attr.policy = THREAD_SCHED_POLICY_TS;
     attr.priority = THREAD_SCHED_TS_PRIO_DEFAULT;
-    error = thread_create(&thread, &attr, kernel_test, NULL);
+    error = thread_create(&thread, &attr, kernel_test_fault, NULL);
     assert(!error);
 }
 
diff --git a/vm/vm_anon.c b/vm/vm_anon.c
index e6d1385f..ebee5fcc 100644
--- a/vm/vm_anon.c
+++ b/vm/vm_anon.c
@@ -113,16 +113,22 @@ vm_anon_get(struct vm_object *object, uint64_t offset,
             struct vm_page **pagep)
 {
     struct vm_page *page;
+    int error;
 
     page = vm_phys_alloc(0);
 
     if (page == NULL)
         return ERROR_NOMEM;
 
-    /* TODO Insert page in object */
-    (void)object;
-    (void)offset;
+    error = vm_object_add(object, offset, page);
+
+    if (error)
+        goto error_object;
 
     *pagep = page;
     return 0;
+
+error_object:
+    vm_phys_free(page, 0);
+    return error;
 }
diff --git a/vm/vm_map.c b/vm/vm_map.c
index 50e9c361..6b43a985 100644
--- a/vm/vm_map.c
+++ b/vm/vm_map.c
@@ -786,6 +786,10 @@ vm_map_enter(struct vm_map *map, struct vm_object *object, uint64_t offset,
     struct vm_map_request request;
     int error;
 
+    /* XXX For now, prevent managed mappings in the kernel map */
+    if ((map == kernel_map) && (object != NULL))
+        return ERROR_INVAL;
+
     mutex_lock(&map->lock);
 
     error = vm_map_prepare(map, object, offset, *startp, size, align, flags,
@@ -922,6 +926,8 @@ vm_map_fault(struct vm_map *map, unsigned long addr, int access)
     uint64_t offset;
     int error, prot;
 
+    assert(map != kernel_map);
+
     addr = vm_page_trunc(addr);
 
     mutex_lock(&map->lock);
@@ -944,7 +950,10 @@ vm_map_fault(struct vm_map *map, unsigned long addr, int access)
     offset = entry->offset + (addr - entry->start);
     page = vm_object_get(object, offset);
 
-    if (page == NULL) {
+    if (page != NULL)
+        printk("vm_map: fault: cache hit\n");
+    else {
+        printk("vm_map: fault: cache miss\n");
         /* TODO Get neighbor pages */
         error = object->pager->get(object, offset, &page);
 
@@ -960,7 +969,6 @@ vm_map_fault(struct vm_map *map, unsigned long addr, int access)
         panic("vm_map: unable to create physical mapping");
 
     pmap_update(map->pmap, addr, addr + PAGE_SIZE);
-    error = 0;
 
 out:
     mutex_unlock(&map->lock);
diff --git a/vm/vm_object.c b/vm/vm_object.c
index 2fa2caae..9e91aad9 100644
--- a/vm/vm_object.c
+++ b/vm/vm_object.c
@@ -15,19 +15,47 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
+#include <kern/assert.h>
+#include <kern/error.h>
+#include <kern/llsync.h>
+#include <kern/mutex.h>
+#include <kern/param.h>
 #include <kern/rdxtree.h>
 #include <kern/stddef.h>
 #include <kern/stdint.h>
 #include <vm/vm_object.h>
 #include <vm/vm_page.h>
 
+int
+vm_object_add(struct vm_object *object, uint64_t offset, struct vm_page *page)
+{
+    int error;
+
+    mutex_lock(&object->lock);
+
+    error = rdxtree_insert(&object->pages, offset >> PAGE_SHIFT, page);
+
+    if (!error)
+        object->nr_pages++;
+
+    mutex_unlock(&object->lock);
+
+    assert(!error || (error == ERROR_NOMEM));
+
+    return error;
+}
+
 struct vm_page *
 vm_object_get(const struct vm_object *object, uint64_t offset)
 {
-    (void)object;
-    (void)offset;
+    struct vm_page *page;
+
+    llsync_read_enter();
+
+    /* TODO Handle page state changes */
+    page = rdxtree_lookup(&object->pages, offset >> PAGE_SHIFT);
 
-    /* TODO Bump radix tree key size to 64-bits */
+    llsync_read_leave();
 
-    return NULL;
+    return page;
 }
diff --git a/vm/vm_object.h b/vm/vm_object.h
index 578720ee..5796846c 100644
--- a/vm/vm_object.h
+++ b/vm/vm_object.h
@@ -64,6 +64,12 @@ vm_object_init(struct vm_object *object, struct vm_object_pager *pager)
 }
 
 /*
+ * Add a page at offset inside an object.
+ */
+int vm_object_add(struct vm_object *object, uint64_t offset,
+                  struct vm_page *page);
+
+/*
  * Get the page at offset inside an object, or NULL if none is found.
  */
 struct vm_page * vm_object_get(const struct vm_object *object, uint64_t offset);