vfs: change how the vfs_create return argument works and split the rdev vattr member

kernel-src/fs/initrd.c

@@ -159,11 +159,7 @@ void initrd_unpack() {
 				VOP_RELEASE(node);
 				break;
 			case TAR_DIR:
-				err = vfs_create(vfsroot, entry.name, &entryattr, V_TYPE_DIR, &node);
-				if (err)
-					break;
-
-				VOP_RELEASE(node);
+				err = vfs_create(vfsroot, entry.name, &entryattr, V_TYPE_DIR, NULL);
 				break;
 			case TAR_SYMLINK:
 				err = vfs_link(NULL, entry.link, vfsroot, entry.name, V_TYPE_LINK, &entryattr);

kernel-src/fs/vfs.c

@@ -93,6 +93,7 @@ int vfs_open(vnode_t *ref, char *path, int flags, vnode_t **res) {
 	return err;
 }
 
+// if node is not NULL, then a reference is kept and the newnode is returned in node
 int vfs_create(vnode_t *ref, char *path, vattr_t *attr, int type, vnode_t **node) {
 	vnode_t *parent;
 	char *component = alloc(strlen(path) + 1);
@@ -100,10 +101,18 @@ int vfs_create(vnode_t *ref, char *path, vattr_t *attr, int type, vnode_t **node
 	if (err)
 		goto cleanup;
 
+	vnode_t *ret;
 	VOP_LOCK(parent);
-	err = VOP_CREATE(parent, component, attr, type, node, getcred());
+	err = VOP_CREATE(parent, component, attr, type, &ret, getcred());
 	VOP_UNLOCK(parent);
 	VOP_RELEASE(parent);
+	if (err)
+		goto cleanup;
+
+	if (node)
+		*node = ret;
+	else
+		VOP_RELEASE(ret);
 
 	cleanup:
 	free(component);

kernel-src/include/kernel/vfs.h

@@ -25,7 +25,8 @@ typedef struct {
 	timespec_t atime;
 	timespec_t mtime;
 	timespec_t ctime;
-	int rdev;
+	int rdevmajor;
+	int rdevminor;
 	size_t blocksused;
 } vattr_t;