This adds support for hiding a device to the qbus and qdev APIs.
qdev_device_add() is modified to check for a standby argument in the
option string. A DeviceListener callback should_be_hidden() is added. It
can be used by a standby device to inform qdev that this device should
not be added now. The standby device handler can store the device
options to plug the device in at a later point in time.
Signed-off-by: Jens Freimann <jfreim...@redhat.com>
---
hw/core/qdev.c | 19 +++++++++++++++++++
hw/vfio/pci.c | 1 +
hw/vfio/pci.h | 1 +
include/hw/qdev-core.h | 9 +++++++++
qdev-monitor.c | 41 ++++++++++++++++++++++++++++++++++++++---
vl.c | 6 ++++--
6 files changed, 72 insertions(+), 5 deletions(-)
diff --git a/hw/core/qdev.c b/hw/core/qdev.c
index 98cdaa6bf7..d55fe00ae7 100644
--- a/hw/core/qdev.c
+++ b/hw/core/qdev.c
@@ -211,6 +211,25 @@ void device_listener_unregister(DeviceListener *listener)
QTAILQ_REMOVE(&device_listeners, listener, link);
}
+bool qdev_should_hide_device(QemuOpts *opts, Error **errp)
+{
+ bool res = false;
+ bool match_found = false;
+
+ DeviceListener *listener;
+
+ QTAILQ_FOREACH(listener, &device_listeners, link) {
+ if (listener->should_be_hidden) {
+ listener->should_be_hidden(listener, opts, &match_found, &res);
+ }
+
+ if (match_found) {
+ break;
+ }
+ }
+ return res;
+}
+
void qdev_set_legacy_instance_id(DeviceState *dev, int alias_id,
int required_for_version)
{
diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c
index 8cecb53d5c..835249c61d 100644
--- a/hw/vfio/pci.c
+++ b/hw/vfio/pci.c
@@ -3215,6 +3215,7 @@ static Property vfio_pci_dev_properties[] = {
display, ON_OFF_AUTO_OFF),
DEFINE_PROP_UINT32("xres", VFIOPCIDevice, display_xres, 0),
DEFINE_PROP_UINT32("yres", VFIOPCIDevice, display_yres, 0),
+ DEFINE_PROP_STRING("standby", VFIOPCIDevice, standby),
DEFINE_PROP_UINT32("x-intx-mmap-timeout-ms", VFIOPCIDevice,
intx.mmap_timeout, 1100),
DEFINE_PROP_BIT("x-vga", VFIOPCIDevice, features,
diff --git a/hw/vfio/pci.h b/hw/vfio/pci.h
index cfcd1a81b8..1a87f91889 100644
--- a/hw/vfio/pci.h
+++ b/hw/vfio/pci.h
@@ -135,6 +135,7 @@ typedef struct VFIOPCIDevice {
PCIHostDeviceAddress host;
EventNotifier err_notifier;
EventNotifier req_notifier;
+ char *standby;
int (*resetfn)(struct VFIOPCIDevice *);
uint32_t vendor_id;
uint32_t device_id;
diff --git a/include/hw/qdev-core.h b/include/hw/qdev-core.h
index 5437395779..d54d3ae62a 100644
--- a/include/hw/qdev-core.h
+++ b/include/hw/qdev-core.h
@@ -158,6 +158,13 @@ struct DeviceState {
struct DeviceListener {
void (*realize)(DeviceListener *listener, DeviceState *dev);
void (*unrealize)(DeviceListener *listener, DeviceState *dev);
+ /*
+ * This callback is called just upon init of the DeviceState
+ * and can be used by a standby device for informing qdev if this
+ * device should be hidden by checking the device opts
+ */
+ void (*should_be_hidden)(DeviceListener *listener, QemuOpts *device_opts,
+ bool *match_found, bool *res);
QTAILQ_ENTRY(DeviceListener) link;
};
@@ -454,4 +461,6 @@ static inline bool qbus_is_hotpluggable(BusState *bus)
void device_listener_register(DeviceListener *listener);
void device_listener_unregister(DeviceListener *listener);
+bool qdev_should_hide_device(QemuOpts *opts, Error **errp);
+
#endif
diff --git a/qdev-monitor.c b/qdev-monitor.c
index 9cce8b93c2..a81226529a 100644
--- a/qdev-monitor.c
+++ b/qdev-monitor.c
@@ -32,8 +32,10 @@
#include "qemu/help_option.h"
#include "qemu/option.h"
#include "qemu/qemu-print.h"
+#include "qemu/option_int.h"
#include "sysemu/block-backend.h"
#include "migration/misc.h"
+#include "migration/migration.h"
/*
* Aliases were a bad idea from the start. Let's keep them
@@ -561,14 +563,45 @@ void qdev_set_id(DeviceState *dev, const char *id)
}
}
+static int is_failover_device(void *opaque, const char *name, const char
*value,
+ Error **errp)
+{
+ if (strcmp(name, "standby") == 0) {
+ QemuOpts *opts = (QemuOpts *)opaque;
+
+ if (qdev_should_hide_device(opts, errp) && errp && !*errp) {
+ return 1;
+ } else if (errp && *errp) {
+ return -1;
+ }
+ }
+
+ return 0;
+}
+
+static bool should_hide_device(QemuOpts *opts, Error **err)
+{
+ if (qemu_opt_foreach(opts, is_failover_device, opts, err) == 0) {
+ return false;
+ }
+ return true;
+}
+
DeviceState *qdev_device_add(QemuOpts *opts, Error **errp)
{
DeviceClass *dc;
const char *driver, *path;
- DeviceState *dev;
+ DeviceState *dev = NULL;
BusState *bus = NULL;
Error *err = NULL;
+ if (opts && should_hide_device(opts, &err)) {
+ if (err) {
+ goto err_del_dev;
+ }
+ return NULL;
+ }
+
driver = qemu_opt_get(opts, "driver");
if (!driver) {
error_setg(errp, QERR_MISSING_PARAMETER, "driver");
@@ -640,8 +673,10 @@ DeviceState *qdev_device_add(QemuOpts *opts, Error **errp)
err_del_dev:
error_propagate(errp, err);
- object_unparent(OBJECT(dev));
- object_unref(OBJECT(dev));
+ if (dev) {
+ object_unparent(OBJECT(dev));
+ object_unref(OBJECT(dev));
+ }
return NULL;
}
diff --git a/vl.c b/vl.c
index b6709514c1..4b5b878275 100644
--- a/vl.c
+++ b/vl.c
@@ -2355,10 +2355,12 @@ static int device_init_func(void *opaque, QemuOpts
*opts, Error **errp)
DeviceState *dev;
dev = qdev_device_add(opts, errp);
- if (!dev) {
+ if (!dev && *errp) {
+ error_report_err(*errp);
return -1;
+ } else if (dev) {
+ object_unref(OBJECT(dev));
}
- object_unref(OBJECT(dev));
return 0;
}
--
2.21.0
