[PATCH v3 12/28] hw/xen: populate store frontend nodes with XenStore PFN/port

David Woodhouse
2023-10-25T14:51:26Z

From: David Woodhouse <dwmw@amazon.co.uk>

This is kind of redundant since without being able to get these through
some other method (HVMOP_get_param) the guest wouldn't be able to access
XenStore in order to find them.

Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Reviewed-by: Paul Durrant <paul@xen.org>
---
hw/i386/kvm/xen_xenstore.c | 11 +++++++++++
1 file changed, 11 insertions(+)

diff --git a/hw/i386/kvm/xen_xenstore.c b/hw/i386/kvm/xen_xenstore.c
index 831da535fc..b7c0407765 100644
--- a/hw/i386/kvm/xen_xenstore.c
+++ b/hw/i386/kvm/xen_xenstore.c
@@ -1434,6 +1434,7 @@ static void alloc_guest_port(XenXenstoreState *s)
int xen_xenstore_reset(void)
{
XenXenstoreState *s = xen_xenstore_singleton;
+ GList *perms;
int err;

if (!s) {
@@ -1461,6 +1462,16 @@ int xen_xenstore_reset(void)
}
s->be_port = err;

+ /* Create frontend store nodes */
+ perms = g_list_append(NULL, xs_perm_as_string(XS_PERM_NONE, DOMID_QEMU));
+ perms = g_list_append(perms, xs_perm_as_string(XS_PERM_READ, xen_domid));
+
+ relpath_printf(s, perms, "store/port", "%u", s->guest_port);
+ relpath_printf(s, perms, "store/ring-ref", "%lu",
+ XEN_SPECIAL_PFN(XENSTORE));
+
+ g_list_free_full(perms, g_free);
+
/*
* We don't actually access the guest's page through the grant, because
* this isn't real Xen, and we can just use the page we gave it in the
--
2.40.1