[PATCH v2 11/15] qdev: Add Error parameter to hide_device() callbacks
hide_device() is used for virtio-net failover, where the standby virtio
device delays creation of the primary device. It only makes sense to
have a single primary device for each standby device. Adding a second
one should result in an error instead of hiding it and never using it
afterwards.
Prepare for this by adding an Error parameter to the hide_device()
callback where virtio-net is informed about adding a primary device.
Signed-off-by: Kevin Wolf <kwolf(a)redhat.com>
---
include/hw/qdev-core.h | 8 ++++++--
hw/core/qdev.c | 7 +++++--
hw/net/virtio-net.c | 2 +-
softmmu/qdev-monitor.c | 5 ++++-
4 files changed, 16 insertions(+), 6 deletions(-)
diff --git a/include/hw/qdev-core.h b/include/hw/qdev-core.h
index 5a073fc368..74d8b614a7 100644
--- a/include/hw/qdev-core.h
+++ b/include/hw/qdev-core.h
@@ -201,8 +201,12 @@ struct DeviceListener {
* informs qdev if a device should be visible or hidden. We can
* hide a failover device depending for example on the device
* opts.
+ *
+ * On errors, it returns false and errp is set. Device creation
+ * should fail in this case.
*/
- bool (*hide_device)(DeviceListener *listener, QemuOpts *device_opts);
+ bool (*hide_device)(DeviceListener *listener, QemuOpts *device_opts,
+ Error **errp);
QTAILQ_ENTRY(DeviceListener) link;
};
@@ -837,7 +841,7 @@ void device_listener_unregister(DeviceListener *listener);
* When a device is added via qdev_device_add() this will be called,
* and return if the device should be added now or not.
*/
-bool qdev_should_hide_device(QemuOpts *opts);
+bool qdev_should_hide_device(QemuOpts *opts, Error **errp);
typedef enum MachineInitPhase {
/* current_machine is NULL. */
diff --git a/hw/core/qdev.c b/hw/core/qdev.c
index d918b50a1d..c3a021c444 100644
--- a/hw/core/qdev.c
+++ b/hw/core/qdev.c
@@ -211,14 +211,17 @@ void device_listener_unregister(DeviceListener *listener)
QTAILQ_REMOVE(&device_listeners, listener, link);
}
-bool qdev_should_hide_device(QemuOpts *opts)
+bool qdev_should_hide_device(QemuOpts *opts, Error **errp)
{
+ ERRP_GUARD();
DeviceListener *listener;
QTAILQ_FOREACH(listener, &device_listeners, link) {
if (listener->hide_device) {
- if (listener->hide_device(listener, opts)) {
+ if (listener->hide_device(listener, opts, errp)) {
return true;
+ } else if (*errp) {
+ return false;
}
}
}
diff --git a/hw/net/virtio-net.c b/hw/net/virtio-net.c
index f205331dcf..a17d5739fc 100644
--- a/hw/net/virtio-net.c
+++ b/hw/net/virtio-net.c
@@ -3304,7 +3304,7 @@ static void virtio_net_migration_state_notifier(Notifier *notifier,
void *data)
}
static bool failover_hide_primary_device(DeviceListener *listener,
- QemuOpts *device_opts)
+ QemuOpts *device_opts, Error **errp)
{
VirtIONet *n = container_of(listener, VirtIONet, primary_listener);
const char *standby_id;
diff --git a/softmmu/qdev-monitor.c b/softmmu/qdev-monitor.c
index feb15818e6..ccc3c11563 100644
--- a/softmmu/qdev-monitor.c
+++ b/softmmu/qdev-monitor.c
@@ -625,6 +625,7 @@ const char *qdev_set_id(DeviceState *dev, char *id, Error **errp)
DeviceState *qdev_device_add(QemuOpts *opts, Error **errp)
{
+ ERRP_GUARD();
DeviceClass *dc;
const char *driver, *path;
DeviceState *dev = NULL;
@@ -668,11 +669,13 @@ DeviceState *qdev_device_add(QemuOpts *opts, Error **errp)
error_setg(errp, "Device with failover_pair_id don't have
id");
return NULL;
}
- if (qdev_should_hide_device(opts)) {
+ if (qdev_should_hide_device(opts, errp)) {
if (bus && !qbus_is_hotpluggable(bus)) {
error_setg(errp, QERR_BUS_NO_HOTPLUG, bus->name);
}
return NULL;
+ } else if (*errp) {
+ return NULL;
}
}
--
2.31.1