From 88ca2033f7e50d0bef0066a738faae79fcaf3279 Mon Sep 17 00:00:00 2001
From: Bahadir Balban <bbalban@b-labs.co.uk>
Date: Sun, 9 Nov 2008 11:37:24 +0200
Subject: [PATCH] Now shared tcb parts freed correctly.

---
 tasks/fs0/src/task.c | 20 +++++++++++++++-----
 tasks/mm0/src/task.c | 36 +++++++++++++++++++++++++++++++-----
 2 files changed, 46 insertions(+), 10 deletions(-)

diff --git a/tasks/fs0/src/task.c b/tasks/fs0/src/task.c
index eb062aa..e172c43 100644
--- a/tasks/fs0/src/task.c
+++ b/tasks/fs0/src/task.c
@@ -143,15 +143,25 @@ struct tcb *tcb_create(struct tcb *orig, l4id_t tid, unsigned long utcb,
 	return task;
 }
 
-/* FIXME: Modify it to work with shared structures!!! */
+/* Free shared structures if no references left */
+void tcb_free_resources(struct tcb *task)
+{
+
+	if (--task->fs_data->tcb_refs == 0)
+		kfree(task->fs_data);
+
+	if (--task->files->tcb_refs == 0) {
+		kfree(task->files->fdpool);
+		kfree(task->files);
+	}
+
+}
+
 void tcb_destroy(struct tcb *task)
 {
 	global_remove_task(task);
 
-	if (--task->fs_data->tcb_refs == 0)
-		kfree(task->fs_data);
-	if (--task->files->tcb_refs == 0)
-		kfree(task->files);
+	tcb_free_resources(task);
 
 	kfree(task);
 }
diff --git a/tasks/mm0/src/task.c b/tasks/mm0/src/task.c
index 1c42a93..4e3ad69 100644
--- a/tasks/mm0/src/task.c
+++ b/tasks/mm0/src/task.c
@@ -111,15 +111,41 @@ struct tcb *tcb_alloc_init(unsigned int flags)
 	return task;
 }
 
-/* NOTE: We may need to delete shared tcb parts here as well. */
+/*
+ * Free vmas, fd structure and utcb address.
+ * Make sure to sync all IO beforehand
+ */
+int task_free_resources(struct tcb *task)
+{
+	/*
+	 * Threads may share file descriptor structure
+	 * if no users left, free it.
+	 */
+	if (!(--task->files->tcb_refs))
+		kfree(task->files);
+
+	/*
+	 * Threads may share the virtual space.
+	 * if no users of the vma struct left,
+	 * free it along with all its vma links.
+	 */
+	if (!(--task->vm_area_head->tcb_refs)) {
+		/* Free all vmas */
+		task_release_vmas(task->vm_area_head);
+
+		/* Free the head */
+		kfree(task->vm_area_head);
+	}
+
+	return 0;
+}
+
 int tcb_destroy(struct tcb *task)
 {
 	global_remove_task(task);
 
-	if (--task->vm_area_head->tcb_refs == 0)
-		kfree(task->vm_area_head);
-	if (--task->files->tcb_refs == 0)
-		kfree(task->files);
+	/* Free all resources of the task */
+	task_free_resources(task);
 
 	kfree(task);