KVM: convert bus to slots_lock
Use slots_lock to protect device list on the bus. slots_lock is already
taken for read everywhere, so we only need to take it for write when
registering devices. This is in preparation to removing in_range and
kvm->lock around it.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
diff --git a/virt/kvm/coalesced_mmio.c b/virt/kvm/coalesced_mmio.c
index b40946c..7b7cc9f 100644
--- a/virt/kvm/coalesced_mmio.c
+++ b/virt/kvm/coalesced_mmio.c
@@ -102,7 +102,7 @@
kvm_iodevice_init(&dev->dev, &coalesced_mmio_ops);
dev->kvm = kvm;
kvm->coalesced_mmio_dev = dev;
- kvm_io_bus_register_dev(&kvm->mmio_bus, &dev->dev);
+ kvm_io_bus_register_dev(kvm, &kvm->mmio_bus, &dev->dev);
return 0;
}
diff --git a/virt/kvm/ioapic.c b/virt/kvm/ioapic.c
index 0532fa6..0eca54e 100644
--- a/virt/kvm/ioapic.c
+++ b/virt/kvm/ioapic.c
@@ -343,7 +343,7 @@
kvm_ioapic_reset(ioapic);
kvm_iodevice_init(&ioapic->dev, &ioapic_mmio_ops);
ioapic->kvm = kvm;
- kvm_io_bus_register_dev(&kvm->mmio_bus, &ioapic->dev);
+ kvm_io_bus_register_dev(kvm, &kvm->mmio_bus, &ioapic->dev);
return 0;
}
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index bbb4029..0edc366 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -2527,7 +2527,17 @@
return NULL;
}
-void kvm_io_bus_register_dev(struct kvm_io_bus *bus, struct kvm_io_device *dev)
+void kvm_io_bus_register_dev(struct kvm *kvm, struct kvm_io_bus *bus,
+ struct kvm_io_device *dev)
+{
+ down_write(&kvm->slots_lock);
+ __kvm_io_bus_register_dev(bus, dev);
+ up_write(&kvm->slots_lock);
+}
+
+/* An unlocked version. Caller must have write lock on slots_lock. */
+void __kvm_io_bus_register_dev(struct kvm_io_bus *bus,
+ struct kvm_io_device *dev)
{
BUG_ON(bus->dev_count > (NR_IOBUS_DEVS-1));