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>

1 files changed, 5 insertions, 3 deletions

diff --git a/arch/ia64/kvm/kvm-ia64.c b/arch/ia64/kvm/kvm-ia64.c
index a312c9e9b9e..8a2b13ff0af 100644
--- a/arch/ia64/kvm/kvm-ia64.c
+++ b/arch/ia64/kvm/kvm-ia64.c
@@ -778,6 +778,9 @@ static void kvm_init_vm(struct kvm *kvm)
         kvm_build_io_pmt(kvm);
 
         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);
 }
 
 struct  kvm *kvm_arch_create_vm(void)
@@ -941,9 +944,8 @@ long kvm_arch_vm_ioctl(struct file *filp,
                         goto out;
                 if (irqchip_in_kernel(kvm)) {
                         mutex_lock(&kvm->lock);
-                        kvm_ioapic_set_irq(kvm->arch.vioapic,
-                                                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;
                 }