From: David Woodhouse
Whem emulating Xen, multi-page grants are distinctly non-trivial and we
have elected not to support them for the time being. Don't advertise
them to the guest.
Signed-off-by: David Woodhouse
---
hw/block/xen-block.c | 11 ---
1 file changed, 8 insertions(+), 3 deletions(-)
diff --git a/hw/block/xen-block.c b/hw/block/xen-block.c
index 87299615e3..f5a744589d 100644
--- a/hw/block/xen-block.c
+++ b/hw/block/xen-block.c
@@ -83,7 +83,8 @@ static void xen_block_connect(XenDevice *xendev, Error **errp)
g_free(ring_ref);
return;
}
-} else if (order <= blockdev->props.max_ring_page_order) {
+} else if (qemu_xen_gnttab_can_map_multi() &&
+ order <= blockdev->props.max_ring_page_order) {
unsigned int i;
nr_ring_ref = 1 << order;
@@ -255,8 +256,12 @@ static void xen_block_realize(XenDevice *xendev, Error
**errp)
}
xen_device_backend_printf(xendev, "feature-flush-cache", "%u", 1);
-xen_device_backend_printf(xendev, "max-ring-page-order", "%u",
- blockdev->props.max_ring_page_order);
+
+if (qemu_xen_gnttab_can_map_multi()) {
+xen_device_backend_printf(xendev, "max-ring-page-order", "%u",
+ blockdev->props.max_ring_page_order);
+}
+
xen_device_backend_printf(xendev, "info", "%u", blockdev->info);
xen_device_frontend_printf(xendev, "virtual-device", "%lu",
--
2.39.0