From: Peter Xu <peterx@redhat.com>
To: qemu-devel@nongnu.org
Cc: peterx@redhat.com, "Fabiano Rosas" <farosas@suse.de>,
"Igor Mammedov" <imammedo@redhat.com>,
"Juraj Marcin" <jmarcin@redhat.com>,
"Michael S . Tsirkin" <mst@redhat.com>,
"Dr . David Alan Gilbert" <dave@treblig.org>,
"Cédric Le Goater" <clg@redhat.com>,
"Markus Armbruster" <armbru@redhat.com>,
"Eduardo Habkost" <eduardo@habkost.net>,
"Daniel P . Berrangé" <berrange@redhat.com>,
"Alex Williamson" <alex.williamson@redhat.com>,
"Paolo Bonzini" <pbonzini@redhat.com>,
"Peter Maydell" <peter.maydell@linaro.org>
Subject: [PATCH 2/4] x86/iommu: Make x86-iommu a singleton object
Date: Thu, 24 Oct 2024 12:56:25 -0400 [thread overview]
Message-ID: <20241024165627.1372621-3-peterx@redhat.com> (raw)
In-Reply-To: <20241024165627.1372621-1-peterx@redhat.com>
X86 IOMMUs cannot be created more than one on a system yet. Make it a
singleton so it guards the system from accidentally create yet another
IOMMU object when one already presents.
Now if someone tries to create more than one, e.g., via:
./qemu -M q35 -device intel-iommu -device intel-iommu
The error will change from:
qemu-system-x86_64: -device intel-iommu: QEMU does not support multiple vIOMMUs for x86 yet.
To:
qemu-system-x86_64: -device intel-iommu: Class 'intel-iommu' only supports one instance
Unfortunately, yet we can't remove the singleton check in the machine
hook (pc_machine_device_pre_plug_cb), because there can also be
virtio-iommu involved, which doesn't share a common parent class yet.
But with this, it should be closer to reach that goal to check singleton by
QOM one day.
Signed-off-by: Peter Xu <peterx@redhat.com>
---
hw/i386/x86-iommu.c | 14 ++++++++++++++
1 file changed, 14 insertions(+)
diff --git a/hw/i386/x86-iommu.c b/hw/i386/x86-iommu.c
index 60af896225..4bfeb08705 100644
--- a/hw/i386/x86-iommu.c
+++ b/hw/i386/x86-iommu.c
@@ -26,6 +26,7 @@
#include "qemu/error-report.h"
#include "trace.h"
#include "sysemu/kvm.h"
+#include "qom/object_interfaces.h"
void x86_iommu_iec_register_notifier(X86IOMMUState *iommu,
iec_notify_fn fn, void *data)
@@ -133,10 +134,19 @@ static Property x86_iommu_properties[] = {
DEFINE_PROP_END_OF_LIST(),
};
+static Object *x86_iommu_get_instance(Error **errp)
+{
+ return OBJECT(x86_iommu_get_default());
+}
+
static void x86_iommu_class_init(ObjectClass *klass, void *data)
{
DeviceClass *dc = DEVICE_CLASS(klass);
+ SingletonClass *singleton = SINGLETON_CLASS(klass);
+
dc->realize = x86_iommu_realize;
+ singleton->get_instance = x86_iommu_get_instance;
+
device_class_set_props(dc, x86_iommu_properties);
}
@@ -152,6 +162,10 @@ static const TypeInfo x86_iommu_info = {
.class_init = x86_iommu_class_init,
.class_size = sizeof(X86IOMMUClass),
.abstract = true,
+ .interfaces = (InterfaceInfo[]) {
+ { TYPE_SINGLETON },
+ { }
+ }
};
static void x86_iommu_register_types(void)
--
2.45.0
next prev parent reply other threads:[~2024-10-24 16:58 UTC|newest]
Thread overview: 38+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-10-24 16:56 [PATCH 0/4] QOM: Singleton interface Peter Xu
2024-10-24 16:56 ` [PATCH 1/4] qom: TYPE_SINGLETON interface Peter Xu
2024-10-24 20:02 ` Philippe Mathieu-Daudé
2024-10-24 20:53 ` Peter Xu
2024-10-25 15:11 ` Philippe Mathieu-Daudé
2024-10-25 16:21 ` Peter Xu
2024-10-25 8:07 ` Markus Armbruster
2024-10-25 15:17 ` Peter Xu
2024-10-25 9:51 ` Daniel P. Berrangé
2024-10-25 16:17 ` Peter Xu
2024-10-25 16:22 ` Daniel P. Berrangé
2024-10-25 22:10 ` Peter Xu
2024-10-29 0:01 ` Peter Xu
2024-10-25 16:37 ` Peter Xu
2024-10-24 16:56 ` Peter Xu [this message]
2024-10-25 9:25 ` [PATCH 2/4] x86/iommu: Make x86-iommu a singleton object Markus Armbruster
2024-10-25 21:55 ` Peter Xu
2024-10-25 22:13 ` Peter Xu
2024-11-07 11:12 ` Markus Armbruster
2024-11-07 15:29 ` Peter Xu
2024-11-08 8:50 ` Markus Armbruster
2024-10-29 10:47 ` Daniel P. Berrangé
2024-10-29 14:32 ` Peter Xu
2024-10-24 16:56 ` [PATCH 3/4] migration: Make migration object " Peter Xu
2024-10-24 19:20 ` Fabiano Rosas
2024-10-24 16:56 ` [PATCH 4/4] migration: Reset current_migration properly Peter Xu
2024-10-24 19:34 ` Fabiano Rosas
2024-10-24 20:15 ` Peter Xu
2024-10-24 20:51 ` Fabiano Rosas
2024-10-25 7:38 ` [PATCH 0/4] QOM: Singleton interface Markus Armbruster
2024-10-25 15:01 ` Peter Xu
2024-10-29 10:42 ` Daniel P. Berrangé
2024-10-29 14:45 ` Peter Xu
2024-10-29 16:04 ` Daniel P. Berrangé
2024-10-29 17:05 ` Peter Xu
2024-10-29 17:17 ` Daniel P. Berrangé
2024-12-11 8:19 ` Markus Armbruster
2024-12-11 22:10 ` Peter Xu
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