kvm/x86: split ioapic-handled and EOI exit bitmaps

The function to determine if the vector is handled by ioapic used to
rely on the fact that only ioapic-handled vectors were set up to
cause vmexits when virtual apic was in use.

We're going to break this assumption when introducing Hyper-V
synthetic interrupts: they may need to cause vmexits too.

To achieve that, introduce a new bitmap dedicated specifically for
ioapic-handled vectors, and populate EOI exit bitmap from it for now.

Signed-off-by: Andrey Smetanin <asmetanin@virtuozzo.com>
Reviewed-by: Roman Kagan <rkagan@virtuozzo.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
CC: Gleb Natapov <gleb@kernel.org>
CC: Paolo Bonzini <pbonzini@redhat.com>
CC: Roman Kagan <rkagan@virtuozzo.com>
CC: Denis V. Lunev <den@openvz.org>
CC: qemu-devel@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

8 files changed, 20 insertions, 18 deletions

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 30cfd64295a0..f6d8894f25b4 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -400,7 +400,7 @@ struct kvm_vcpu_arch {
         u64 efer;
         u64 apic_base;
         struct kvm_lapic *apic;    /* kernel irqchip context */
-        u64 eoi_exit_bitmap[4];
+        DECLARE_BITMAP(ioapic_handled_vectors, 256);
         unsigned long apic_attention;
         int32_t apic_arb_prio;
         int mp_state;
@@ -834,7 +834,7 @@ struct kvm_x86_ops {
         int (*cpu_uses_apicv)(struct kvm_vcpu *vcpu);
         void (*hwapic_irr_update)(struct kvm_vcpu *vcpu, int max_irr);
         void (*hwapic_isr_update)(struct kvm *kvm, int isr);
-        void (*load_eoi_exitmap)(struct kvm_vcpu *vcpu);
+        void (*load_eoi_exitmap)(struct kvm_vcpu *vcpu, u64 *eoi_exit_bitmap);
         void (*set_virtual_x2apic_mode)(struct kvm_vcpu *vcpu, bool set);
         void (*set_apic_access_page_addr)(struct kvm_vcpu *vcpu, hpa_t hpa);
         void (*deliver_posted_interrupt)(struct kvm_vcpu *vcpu, int vector);
diff --git a/arch/x86/kvm/ioapic.c b/arch/x86/kvm/ioapic.c
index 88d0a92d3f94..1facfd60b04a 100644
--- a/arch/x86/kvm/ioapic.c
+++ b/arch/x86/kvm/ioapic.c
@@ -233,7 +233,7 @@ static void kvm_ioapic_inject_all(struct kvm_ioapic *ioapic, unsigned long irr)
 }
 
 
-void kvm_ioapic_scan_entry(struct kvm_vcpu *vcpu, u64 *eoi_exit_bitmap)
+void kvm_ioapic_scan_entry(struct kvm_vcpu *vcpu, ulong *ioapic_handled_vectors)
 {
         struct kvm_ioapic *ioapic = vcpu->kvm->arch.vioapic;
         union kvm_ioapic_redirect_entry *e;
@@ -250,7 +250,7 @@ void kvm_ioapic_scan_entry(struct kvm_vcpu *vcpu, u64 *eoi_exit_bitmap)
                             (e->fields.trig_mode == IOAPIC_EDGE_TRIG &&
                              kvm_apic_pending_eoi(vcpu, e->fields.vector)))
                                 __set_bit(e->fields.vector,
-                                        (unsigned long *)eoi_exit_bitmap);
+                                          ioapic_handled_vectors);
                 }
         }
         spin_unlock(&ioapic->lock);
diff --git a/arch/x86/kvm/ioapic.h b/arch/x86/kvm/ioapic.h
index 084617d37c74..2d16dc251d81 100644
--- a/arch/x86/kvm/ioapic.h
+++ b/arch/x86/kvm/ioapic.h
@@ -121,7 +121,8 @@ int kvm_irq_delivery_to_apic(struct kvm *kvm, struct kvm_lapic *src,
                 struct kvm_lapic_irq *irq, unsigned long *dest_map);
 int kvm_get_ioapic(struct kvm *kvm, struct kvm_ioapic_state *state);
 int kvm_set_ioapic(struct kvm *kvm, struct kvm_ioapic_state *state);
-void kvm_ioapic_scan_entry(struct kvm_vcpu *vcpu, u64 *eoi_exit_bitmap);
-void kvm_scan_ioapic_routes(struct kvm_vcpu *vcpu, u64 *eoi_exit_bitmap);
-
+void kvm_ioapic_scan_entry(struct kvm_vcpu *vcpu,
+                           ulong *ioapic_handled_vectors);
+void kvm_scan_ioapic_routes(struct kvm_vcpu *vcpu,
+                            ulong *ioapic_handled_vectors);
 #endif
diff --git a/arch/x86/kvm/irq_comm.c b/arch/x86/kvm/irq_comm.c
index e39768ca8285..ece901c29351 100644
--- a/arch/x86/kvm/irq_comm.c
+++ b/arch/x86/kvm/irq_comm.c
@@ -339,7 +339,8 @@ void kvm_arch_post_irq_routing_update(struct kvm *kvm)
         kvm_make_scan_ioapic_request(kvm);
 }
 
-void kvm_scan_ioapic_routes(struct kvm_vcpu *vcpu, u64 *eoi_exit_bitmap)
+void kvm_scan_ioapic_routes(struct kvm_vcpu *vcpu,
+                            ulong *ioapic_handled_vectors)
 {
         struct kvm *kvm = vcpu->kvm;
         struct kvm_kernel_irq_routing_entry *entry;
@@ -369,7 +370,7 @@ void kvm_scan_ioapic_routes(struct kvm_vcpu *vcpu, u64 *eoi_exit_bitmap)
                                 u32 vector = entry->msi.data & 0xff;
 
                                 __set_bit(vector,
-                                          (unsigned long *) eoi_exit_bitmap);
+                                          ioapic_handled_vectors);
                         }
                 }
         }
diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index 4d30b865be30..9469d453abc8 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -932,7 +932,7 @@ int kvm_apic_compare_prio(struct kvm_vcpu *vcpu1, struct kvm_vcpu *vcpu2)
 
 static bool kvm_ioapic_handles_vector(struct kvm_lapic *apic, int vector)
 {
-        return test_bit(vector, (ulong *)apic->vcpu->arch.eoi_exit_bitmap);
+        return test_bit(vector, apic->vcpu->arch.ioapic_handled_vectors);
 }
 
 static void kvm_ioapic_send_eoi(struct kvm_lapic *apic, int vector)
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index 83a1c643f9a5..ebb76e8a91e1 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -3564,7 +3564,7 @@ static int svm_cpu_uses_apicv(struct kvm_vcpu *vcpu)
         return 0;
 }
 
-static void svm_load_eoi_exitmap(struct kvm_vcpu *vcpu)
+static void svm_load_eoi_exitmap(struct kvm_vcpu *vcpu, u64 *eoi_exit_bitmap)
 {
         return;
 }
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index af823a388c19..c8a87c94dc81 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -8257,9 +8257,8 @@ static void vmx_hwapic_irr_update(struct kvm_vcpu *vcpu, int max_irr)
         }
 }
 
-static void vmx_load_eoi_exitmap(struct kvm_vcpu *vcpu)
+static void vmx_load_eoi_exitmap(struct kvm_vcpu *vcpu, u64 *eoi_exit_bitmap)
 {
-        u64 *eoi_exit_bitmap = vcpu->arch.eoi_exit_bitmap;
         if (!vmx_cpu_uses_apicv(vcpu))
                 return;
 
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index eed32283d22c..9c69337a3d61 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -6301,15 +6301,16 @@ static void vcpu_scan_ioapic(struct kvm_vcpu *vcpu)
         if (!kvm_apic_hw_enabled(vcpu->arch.apic))
                 return;
 
-        memset(vcpu->arch.eoi_exit_bitmap, 0, 256 / 8);
+        bitmap_zero(vcpu->arch.ioapic_handled_vectors, 256);
 
         if (irqchip_split(vcpu->kvm))
-                kvm_scan_ioapic_routes(vcpu, vcpu->arch.eoi_exit_bitmap);
+                kvm_scan_ioapic_routes(vcpu, vcpu->arch.ioapic_handled_vectors);
         else {
                 kvm_x86_ops->sync_pir_to_irr(vcpu);
-                kvm_ioapic_scan_entry(vcpu, vcpu->arch.eoi_exit_bitmap);
+                kvm_ioapic_scan_entry(vcpu, vcpu->arch.ioapic_handled_vectors);
         }
-        kvm_x86_ops->load_eoi_exitmap(vcpu);
+        kvm_x86_ops->load_eoi_exitmap(vcpu,
+                                      (u64 *)vcpu->arch.ioapic_handled_vectors);
 }
 
 static void kvm_vcpu_flush_tlb(struct kvm_vcpu *vcpu)
@@ -6417,7 +6418,7 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu)
                 if (kvm_check_request(KVM_REQ_IOAPIC_EOI_EXIT, vcpu)) {
                         BUG_ON(vcpu->arch.pending_ioapic_eoi > 255);
                         if (test_bit(vcpu->arch.pending_ioapic_eoi,
-                                     (void *) vcpu->arch.eoi_exit_bitmap)) {
+                                     vcpu->arch.ioapic_handled_vectors)) {
                                 vcpu->run->exit_reason = KVM_EXIT_IOAPIC_EOI;
                                 vcpu->run->eoi.vector =
                                                 vcpu->arch.pending_ioapic_eoi;