From: Michael S. Tsirkin <[email protected]> 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 <[email protected]> Signed-off-by: Avi Kivity <[email protected]> diff --git a/arch/x86/kvm/i8254.c b/arch/x86/kvm/i8254.c index 6e0a203..c0528f1 100644 --- a/arch/x86/kvm/i8254.c +++ b/arch/x86/kvm/i8254.c @@ -580,6 +580,7 @@ static const struct kvm_io_device_ops speaker_dev_ops = { .in_range = speaker_in_range, }; +/* Caller must have writers lock on slots_lock */ struct kvm_pit *kvm_create_pit(struct kvm *kvm, u32 flags) { struct kvm_pit *pit; @@ -618,11 +619,11 @@ 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->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->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 1a8952f..e3a7672 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 +62,9 @@ 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_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); 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 947af6f..2a2181a 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -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)); -- To unsubscribe from this list: send the line "unsubscribe kvm-commits" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
