Hi,
On Tue, Jul 07, 2009 at 09:24:27PM +0300, Sergiu Ivanov wrote:
> In the latest working design unionmount creates a proxy node (by
> cloning the netfs_root_node of unionfs translator) and sets the
> mountee on this proxy. I'm currently trying to implement cfhammar's
> idea about having the mountee run in orphan mode. To achieve this I
> call only fshelp_start_translator, with no file_set_translator
> following. When calling fshelp_start_translator, I have to give a
> pointer to a function, open_port, which in my case looks like this:
>
> /* Opens the port on which to set the mountee. */
> error_t
> open_port (int flags, mach_port_t * underlying,
> mach_msg_type_name_t * underlying_type, task_t task,
> void *cookie)
> {
> err = 0;
>
> /* Create a port to `np`. */
> newpi = netfs_make_protid
> (netfs_make_peropen (np, flags, NULL), user);
> if (!newpi)
> {
> iohelp_free_iouser (user);
> return errno;
> }
>
> *underlying = underlying_port = ports_get_send_right (newpi);
> *underlying_type = MACH_MSG_TYPE_COPY_SEND;
>
> ports_port_deref (newpi);
>
> return err;
> } /*open_port */
>
> np is the pointer to the proxy node. If I want to get rid of the
> proxy node I must somehow avoid keeping references to it. However, in
> the above code I clearly add a reference to the proxy node by creating
> a port which goes to the mountee and thus, does not get destroyed
> immediately.
Is there any reason to have a proxy at all now that there's no
file_set_translator? Why not simply pass unionfs's underlying node?
Regards,
Fredrik
