Re: [PATCH v6 14/18] xen/pvcalls: disconnect and module_exit

From: Juergen Gross
Date: Tue Jul 04 2017 - 03:32:48 EST


On 03/07/17 23:08, Stefano Stabellini wrote:
> Implement backend_disconnect. Call pvcalls_back_release_active on active
> sockets and pvcalls_back_release_passive on passive sockets.
>
> Implement module_exit by calling backend_disconnect on frontend
> connections.
>
> Signed-off-by: Stefano Stabellini <stefano@xxxxxxxxxxx>
> CC: boris.ostrovsky@xxxxxxxxxx
> CC: jgross@xxxxxxxx
> ---
> drivers/xen/pvcalls-back.c | 52 ++++++++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 52 insertions(+)
>
> diff --git a/drivers/xen/pvcalls-back.c b/drivers/xen/pvcalls-back.c
> index 9f4247f..71a42fc 100644
> --- a/drivers/xen/pvcalls-back.c
> +++ b/drivers/xen/pvcalls-back.c
> @@ -807,6 +807,42 @@ static int backend_connect(struct xenbus_device *dev)
>
> static int backend_disconnect(struct xenbus_device *dev)
> {
> + struct pvcalls_fedata *fedata;
> + struct sock_mapping *map, *n;
> + struct sockpass_mapping *mappass;
> + struct radix_tree_iter iter;
> + void **slot;
> +
> +
> + fedata = dev_get_drvdata(&dev->dev);
> +
> + down(&fedata->socket_lock);
> + list_for_each_entry_safe(map, n, &fedata->socket_mappings, list) {
> + list_del(&map->list);
> + pvcalls_back_release_active(dev, fedata, map);
> + }
> +
> + radix_tree_for_each_slot(slot, &fedata->socketpass_mappings, &iter, 0) {
> + mappass = radix_tree_deref_slot(slot);
> + if (!mappass)
> + continue;
> + if (radix_tree_exception(mappass)) {
> + if (radix_tree_deref_retry(mappass))
> + slot = radix_tree_iter_retry(&iter);
> + } else {
> + radix_tree_delete(&fedata->socketpass_mappings, mappass->id);
> + pvcalls_back_release_passive(dev, fedata, mappass);
> + }
> + }
> + up(&fedata->socket_lock);
> +
> + xenbus_unmap_ring_vfree(dev, fedata->sring);
> + unbind_from_irqhandler(fedata->irq, dev);

Swap above two lines to avoid irq being handled after releasing
ring?


Juergen