KVM: Fix guest shared interrupt with in-kernel irqchip
Every call of kvm_set_irq() should offer an irq_source_id, which is
allocated by kvm_request_irq_source_id(). Based on irq_source_id, we
identify the irq source and implement logical OR for shared level
interrupts.
The allocated irq_source_id can be freed by kvm_free_irq_source_id().
Currently, we support at most sizeof(unsigned long) different irq sources.
[Amit: - rebase to kvm.git HEAD
- move definition of KVM_USERSPACE_IRQ_SOURCE_ID to common file
- move kvm_request_irq_source_id to the update_irq ioctl]
[Xiantao: - Add kvm/ia64 stuff and make it work for kvm/ia64 guests]
Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Xiantao Zhang <xiantao.zhang@intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 65679d0..8346be8 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -364,6 +364,9 @@
struct page *ept_identity_pagetable;
bool ept_identity_pagetable_done;
+
+ unsigned long irq_sources_bitmap;
+ unsigned long irq_states[KVM_IOAPIC_NUM_PINS];
};
struct kvm_vm_stat {
diff --git a/arch/x86/kvm/i8254.c b/arch/x86/kvm/i8254.c
index 11c6725..8772dc9 100644
--- a/arch/x86/kvm/i8254.c
+++ b/arch/x86/kvm/i8254.c
@@ -545,6 +545,12 @@
if (!pit)
return NULL;
+ mutex_lock(&kvm->lock);
+ pit->irq_source_id = kvm_request_irq_source_id(kvm);
+ mutex_unlock(&kvm->lock);
+ if (pit->irq_source_id < 0)
+ return NULL;
+
mutex_init(&pit->pit_state.lock);
mutex_lock(&pit->pit_state.lock);
spin_lock_init(&pit->pit_state.inject_lock);
@@ -587,6 +593,7 @@
mutex_lock(&kvm->arch.vpit->pit_state.lock);
timer = &kvm->arch.vpit->pit_state.pit_timer.timer;
hrtimer_cancel(timer);
+ kvm_free_irq_source_id(kvm, kvm->arch.vpit->irq_source_id);
mutex_unlock(&kvm->arch.vpit->pit_state.lock);
kfree(kvm->arch.vpit);
}
@@ -595,8 +602,8 @@
static void __inject_pit_timer_intr(struct kvm *kvm)
{
mutex_lock(&kvm->lock);
- kvm_set_irq(kvm, 0, 1);
- kvm_set_irq(kvm, 0, 0);
+ kvm_set_irq(kvm, kvm->arch.vpit->irq_source_id, 0, 1);
+ kvm_set_irq(kvm, kvm->arch.vpit->irq_source_id, 0, 0);
mutex_unlock(&kvm->lock);
}
diff --git a/arch/x86/kvm/i8254.h b/arch/x86/kvm/i8254.h
index e436d49..4178022 100644
--- a/arch/x86/kvm/i8254.h
+++ b/arch/x86/kvm/i8254.h
@@ -44,6 +44,7 @@
struct kvm_io_device speaker_dev;
struct kvm *kvm;
struct kvm_kpit_state pit_state;
+ int irq_source_id;
};
#define KVM_PIT_BASE_ADDRESS 0x40
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 4f0677d..f1f8ff2 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -1742,7 +1742,8 @@
goto out;
if (irqchip_in_kernel(kvm)) {
mutex_lock(&kvm->lock);
- kvm_set_irq(kvm, irq_event.irq, irq_event.level);
+ kvm_set_irq(kvm, KVM_USERSPACE_IRQ_SOURCE_ID,
+ irq_event.irq, irq_event.level);
mutex_unlock(&kvm->lock);
r = 0;
}
@@ -4013,6 +4014,9 @@
INIT_LIST_HEAD(&kvm->arch.active_mmu_pages);
INIT_LIST_HEAD(&kvm->arch.assigned_dev_head);
+ /* Reserve bit 0 of irq_sources_bitmap for userspace irq source */
+ set_bit(KVM_USERSPACE_IRQ_SOURCE_ID, &kvm->arch.irq_sources_bitmap);
+
return kvm;
}