| Message ID | 20090629120911.GD21273@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Mon, Jun 29, 2009 at 03:09:11PM +0300, Michael S. Tsirkin wrote: > 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> > --- > arch/x86/kvm/i8254.c | 4 ++-- > arch/x86/kvm/i8259.c | 2 +- > include/linux/kvm_host.h | 3 ++- > virt/kvm/ioapic.c | 2 +- > virt/kvm/kvm_main.c | 5 ++++- > 5 files changed, 10 insertions(+), 6 deletions(-) > > diff --git a/arch/x86/kvm/i8254.c b/arch/x86/kvm/i8254.c > index 331705f..c2387ec 100644 > --- a/arch/x86/kvm/i8254.c > +++ b/arch/x86/kvm/i8254.c > @@ -620,11 +620,11 @@ struct kvm_pit *kvm_create_pit(struct kvm *kvm, u32 flags) > kvm_register_irq_mask_notifier(kvm, 0, &pit->mask_notifier); > > kvm_iodevice_init(&pit->dev, &pit_dev_ops); > - kvm_io_bus_register_dev(&kvm->pio_bus, &pit->dev); > + kvm_io_bus_register_dev(kvm, &kvm->pio_bus, &pit->dev); > > if (flags & KVM_PIT_SPEAKER_DUMMY) { > kvm_iodevice_init(&pit->speaker_dev, &speaker_dev_ops); > - kvm_io_bus_register_dev(&kvm->pio_bus, &pit->speaker_dev); > + kvm_io_bus_register_dev(kvm, &kvm->pio_bus, &pit->speaker_dev); > } > > return pit; > diff --git a/arch/x86/kvm/i8259.c b/arch/x86/kvm/i8259.c > index 148c52a..1851aec 100644 > --- a/arch/x86/kvm/i8259.c > +++ b/arch/x86/kvm/i8259.c > @@ -548,6 +548,6 @@ struct kvm_pic *kvm_create_pic(struct kvm *kvm) > * Initialize PIO device > */ > kvm_iodevice_init(&s->dev, &picdev_ops); > - kvm_io_bus_register_dev(&kvm->pio_bus, &s->dev); > + kvm_io_bus_register_dev(kvm, &kvm->pio_bus, &s->dev); > return s; case KVM_CREATE_PIT2: create_pit: mutex_lock(&kvm->lock); kvm_io_bus_register_dev down_write(slots_lock); But the order is slots_lock -> kvm->lock. (you might want to update the comment on top of kvm_main.c to reflect that). -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/arch/x86/kvm/i8254.c b/arch/x86/kvm/i8254.c index 331705f..c2387ec 100644 --- a/arch/x86/kvm/i8254.c +++ b/arch/x86/kvm/i8254.c @@ -620,11 +620,11 @@ struct kvm_pit *kvm_create_pit(struct kvm *kvm, u32 flags) kvm_register_irq_mask_notifier(kvm, 0, &pit->mask_notifier); kvm_iodevice_init(&pit->dev, &pit_dev_ops); - kvm_io_bus_register_dev(&kvm->pio_bus, &pit->dev); + kvm_io_bus_register_dev(kvm, &kvm->pio_bus, &pit->dev); if (flags & KVM_PIT_SPEAKER_DUMMY) { kvm_iodevice_init(&pit->speaker_dev, &speaker_dev_ops); - kvm_io_bus_register_dev(&kvm->pio_bus, &pit->speaker_dev); + kvm_io_bus_register_dev(kvm, &kvm->pio_bus, &pit->speaker_dev); } return pit; diff --git a/arch/x86/kvm/i8259.c b/arch/x86/kvm/i8259.c index 148c52a..1851aec 100644 --- a/arch/x86/kvm/i8259.c +++ b/arch/x86/kvm/i8259.c @@ -548,6 +548,6 @@ struct kvm_pic *kvm_create_pic(struct kvm *kvm) * Initialize PIO device */ kvm_iodevice_init(&s->dev, &picdev_ops); - kvm_io_bus_register_dev(&kvm->pio_bus, &s->dev); + kvm_io_bus_register_dev(kvm, &kvm->pio_bus, &s->dev); return s; } diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index 2451f48..8b1ee3f 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -42,6 +42,7 @@ #define KVM_USERSPACE_IRQ_SOURCE_ID 0 +struct kvm; struct kvm_vcpu; extern struct kmem_cache *kvm_vcpu_cache; @@ -61,7 +62,7 @@ void kvm_io_bus_init(struct kvm_io_bus *bus); void kvm_io_bus_destroy(struct kvm_io_bus *bus); struct kvm_io_device *kvm_io_bus_find_dev(struct kvm_io_bus *bus, gpa_t addr, int len, int is_write); -void kvm_io_bus_register_dev(struct kvm_io_bus *bus, +void kvm_io_bus_register_dev(struct kvm *kvm, struct kvm_io_bus *bus, struct kvm_io_device *dev); struct kvm_vcpu { diff --git a/virt/kvm/ioapic.c b/virt/kvm/ioapic.c index d8b2eca..ad80ead 100644 --- a/virt/kvm/ioapic.c +++ b/virt/kvm/ioapic.c @@ -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; } diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 58d6bc6..7bb2821 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -2499,11 +2499,14 @@ 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); BUG_ON(bus->dev_count > (NR_IOBUS_DEVS-1)); bus->devs[bus->dev_count++] = dev; + up_write(&kvm->slots_lock); } static struct notifier_block kvm_cpu_notifier = {
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> --- arch/x86/kvm/i8254.c | 4 ++-- arch/x86/kvm/i8259.c | 2 +- include/linux/kvm_host.h | 3 ++- virt/kvm/ioapic.c | 2 +- virt/kvm/kvm_main.c | 5 ++++- 5 files changed, 10 insertions(+), 6 deletions(-)