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>
This commit is contained in:
Michael S. Tsirkin
2009-06-29 22:24:26 +03:00
committed by Avi Kivity
parent 108b56690f
commit 6c47469453
6 changed files with 21 additions and 7 deletions

View File

@ -102,7 +102,7 @@ int kvm_coalesced_mmio_init(struct kvm *kvm)
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;
}

View File

@ -343,7 +343,7 @@ int kvm_ioapic_init(struct kvm *kvm)
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;
}

View File

@ -2527,7 +2527,17 @@ struct kvm_io_device *kvm_io_bus_find_dev(struct kvm_io_bus *bus,
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));