From 090b7aff27120cdae76a346a70db394844fea598 Mon Sep 17 00:00:00 2001 From: Gregory Haskins Date: Tue, 7 Jul 2009 17:08:44 -0400 Subject: KVM: make io_bus interface more robust Today kvm_io_bus_regsiter_dev() returns void and will internally BUG_ON if it fails. We want to create dynamic MMIO/PIO entries driven from userspace later in the series, so we need to enhance the code to be more robust with the following changes: 1) Add a return value to the registration function 2) Fix up all the callsites to check the return code, handle any failures, and percolate the error up to the caller. 3) Add an unregister function that collapses holes in the array Signed-off-by: Gregory Haskins Acked-by: Michael S. Tsirkin Signed-off-by: Avi Kivity --- arch/x86/kvm/i8254.c | 20 ++++++++++++++++++-- 1 file changed, 18 insertions(+), 2 deletions(-) (limited to 'arch/x86/kvm/i8254.c') diff --git a/arch/x86/kvm/i8254.c b/arch/x86/kvm/i8254.c index 9b62c57ba6e..137e5481710 100644 --- a/arch/x86/kvm/i8254.c +++ b/arch/x86/kvm/i8254.c @@ -605,6 +605,7 @@ struct kvm_pit *kvm_create_pit(struct kvm *kvm, u32 flags) { struct kvm_pit *pit; struct kvm_kpit_state *pit_state; + int ret; pit = kzalloc(sizeof(struct kvm_pit), GFP_KERNEL); if (!pit) @@ -639,14 +640,29 @@ 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); + ret = __kvm_io_bus_register_dev(&kvm->pio_bus, &pit->dev); + if (ret < 0) + goto fail; 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); + ret = __kvm_io_bus_register_dev(&kvm->pio_bus, + &pit->speaker_dev); + if (ret < 0) + goto fail_unregister; } return pit; + +fail_unregister: + __kvm_io_bus_unregister_dev(&kvm->pio_bus, &pit->dev); + +fail: + if (pit->irq_source_id >= 0) + kvm_free_irq_source_id(kvm, pit->irq_source_id); + + kfree(pit); + return NULL; } void kvm_free_pit(struct kvm *kvm) -- cgit v1.2.3