Commit 75858a84 authored by Avi Kivity's avatar Avi Kivity
Browse files

KVM: Interrupt mask notifiers for ioapic 



Allow clients to request notifications when the guest masks or unmasks a
particular irq line.  This complements irq ack notifications, as the guest
will not ack an irq line that is masked.

Currently implemented for the ioapic only.

Signed-off-by: default avatarAvi Kivity <avi@redhat.com>
parent 5d9b8e30

include/linux/kvm_host.h

+17 −0
Original line number Diff line number Diff line
@@ -127,6 +127,10 @@ struct kvm { 
	struct kvm_coalesced_mmio_ring *coalesced_mmio_ring;

#endif



#ifdef CONFIG_HAVE_KVM_IRQCHIP

	struct hlist_head mask_notifier_list;

#endif



#ifdef KVM_ARCH_WANT_MMU_NOTIFIER

	struct mmu_notifier mmu_notifier;

	unsigned long mmu_notifier_seq;
@@ -320,6 +324,19 @@ struct kvm_assigned_dev_kernel { 
	struct pci_dev *dev;

	struct kvm *kvm;

};



struct kvm_irq_mask_notifier {

	void (*func)(struct kvm_irq_mask_notifier *kimn, bool masked);

	int irq;

	struct hlist_node link;

};



void kvm_register_irq_mask_notifier(struct kvm *kvm, int irq,

				    struct kvm_irq_mask_notifier *kimn);

void kvm_unregister_irq_mask_notifier(struct kvm *kvm, int irq,

				      struct kvm_irq_mask_notifier *kimn);

void kvm_fire_mask_notifiers(struct kvm *kvm, int irq, bool mask);



void kvm_set_irq(struct kvm *kvm, int irq_source_id, int irq, int level);

void kvm_notify_acked_irq(struct kvm *kvm, unsigned gsi);

void kvm_register_irq_ack_notifier(struct kvm *kvm,

virt/kvm/ioapic.c

+6 −0
Original line number Diff line number Diff line
@@ -101,6 +101,7 @@ static void ioapic_service(struct kvm_ioapic *ioapic, unsigned int idx) 
static void ioapic_write_indirect(struct kvm_ioapic *ioapic, u32 val)

{

	unsigned index;

	bool mask_before, mask_after;



	switch (ioapic->ioregsel) {

	case IOAPIC_REG_VERSION:
@@ -120,6 +121,7 @@ static void ioapic_write_indirect(struct kvm_ioapic *ioapic, u32 val) 
		ioapic_debug("change redir index %x val %x\n", index, val);

		if (index >= IOAPIC_NUM_PINS)

			return;

		mask_before = ioapic->redirtbl[index].fields.mask;

		if (ioapic->ioregsel & 1) {

			ioapic->redirtbl[index].bits &= 0xffffffff;

			ioapic->redirtbl[index].bits |= (u64) val << 32;
@@ -128,6 +130,9 @@ static void ioapic_write_indirect(struct kvm_ioapic *ioapic, u32 val) 
			ioapic->redirtbl[index].bits |= (u32) val;

			ioapic->redirtbl[index].fields.remote_irr = 0;

		}

		mask_after = ioapic->redirtbl[index].fields.mask;

		if (mask_before != mask_after)

			kvm_fire_mask_notifiers(ioapic->kvm, index, mask_after);

		if (ioapic->irr & (1 << index))

			ioapic_service(ioapic, index);

		break;
@@ -426,3 +431,4 @@ int kvm_ioapic_init(struct kvm *kvm) 
	kvm_io_bus_register_dev(&kvm->mmio_bus, &ioapic->dev);

	return 0;

}

virt/kvm/irq_comm.c

+24 −0
Original line number Diff line number Diff line
@@ -99,3 +99,27 @@ void kvm_free_irq_source_id(struct kvm *kvm, int irq_source_id) 
		clear_bit(irq_source_id, &kvm->arch.irq_states[i]);

	clear_bit(irq_source_id, &kvm->arch.irq_sources_bitmap);

}



void kvm_register_irq_mask_notifier(struct kvm *kvm, int irq,

				    struct kvm_irq_mask_notifier *kimn)

{

	kimn->irq = irq;

	hlist_add_head(&kimn->link, &kvm->mask_notifier_list);

}



void kvm_unregister_irq_mask_notifier(struct kvm *kvm, int irq,

				      struct kvm_irq_mask_notifier *kimn)

{

	hlist_del(&kimn->link);

}



void kvm_fire_mask_notifiers(struct kvm *kvm, int irq, bool mask)

{

	struct kvm_irq_mask_notifier *kimn;

	struct hlist_node *n;



	hlist_for_each_entry(kimn, n, &kvm->mask_notifier_list, link)

		if (kimn->irq == irq)

			kimn->func(kimn, mask);

}

virt/kvm/kvm_main.c

+3 −0
Original line number Diff line number Diff line
@@ -842,6 +842,9 @@ static struct kvm *kvm_create_vm(void) 


	if (IS_ERR(kvm))

		goto out;

#ifdef CONFIG_HAVE_KVM_IRQCHIP

	INIT_HLIST_HEAD(&kvm->mask_notifier_list);

#endif



#ifdef KVM_COALESCED_MMIO_PAGE_OFFSET

	page = alloc_page(GFP_KERNEL | __GFP_ZERO);