KVM: x86: Move kvm_irq_delivery_to_apic() from irq.c to lapic.c

Move kvm_irq_delivery_to_apic() to lapic.c as it is specific to local APIC
emulation.  This will allow burying more local APIC code in lapic.c, e.g.
the various "lowest priority" helpers.

No functional change intended.

Link: https://lore.kernel.org/r/20250821214209.3463350-2-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>

Author: sean-jc

arch/x86/kvm/irq.c

@@ -195,63 +195,6 @@ bool kvm_arch_irqchip_in_kernel(struct kvm *kvm)
 	return irqchip_in_kernel(kvm);
 }
 
-int kvm_irq_delivery_to_apic(struct kvm *kvm, struct kvm_lapic *src,
-			     struct kvm_lapic_irq *irq, struct dest_map *dest_map)
-{
-	int r = -1;
-	struct kvm_vcpu *vcpu, *lowest = NULL;
-	unsigned long i, dest_vcpu_bitmap[BITS_TO_LONGS(KVM_MAX_VCPUS)];
-	unsigned int dest_vcpus = 0;
-
-	if (kvm_irq_delivery_to_apic_fast(kvm, src, irq, &r, dest_map))
-		return r;
-
-	if (irq->dest_mode == APIC_DEST_PHYSICAL &&
-	    irq->dest_id == 0xff && kvm_lowest_prio_delivery(irq)) {
-		pr_info("apic: phys broadcast and lowest prio\n");
-		irq->delivery_mode = APIC_DM_FIXED;
-	}
-
-	memset(dest_vcpu_bitmap, 0, sizeof(dest_vcpu_bitmap));
-
-	kvm_for_each_vcpu(i, vcpu, kvm) {
-		if (!kvm_apic_present(vcpu))
-			continue;
-
-		if (!kvm_apic_match_dest(vcpu, src, irq->shorthand,
-					irq->dest_id, irq->dest_mode))
-			continue;
-
-		if (!kvm_lowest_prio_delivery(irq)) {
-			if (r < 0)
-				r = 0;
-			r += kvm_apic_set_irq(vcpu, irq, dest_map);
-		} else if (kvm_apic_sw_enabled(vcpu->arch.apic)) {
-			if (!kvm_vector_hashing_enabled()) {
-				if (!lowest)
-					lowest = vcpu;
-				else if (kvm_apic_compare_prio(vcpu, lowest) < 0)
-					lowest = vcpu;
-			} else {
-				__set_bit(i, dest_vcpu_bitmap);
-				dest_vcpus++;
-			}
-		}
-	}
-
-	if (dest_vcpus != 0) {
-		int idx = kvm_vector_to_index(irq->vector, dest_vcpus,
-					dest_vcpu_bitmap, KVM_MAX_VCPUS);
-
-		lowest = kvm_get_vcpu(kvm, idx);
-	}
-
-	if (lowest)
-		r = kvm_apic_set_irq(lowest, irq, dest_map);
-
-	return r;
-}
-
 static void kvm_msi_to_lapic_irq(struct kvm *kvm,
 				 struct kvm_kernel_irq_routing_entry *e,
 				 struct kvm_lapic_irq *irq)

arch/x86/kvm/irq.h

@@ -121,8 +121,4 @@ void __kvm_migrate_timers(struct kvm_vcpu *vcpu);
 
 int apic_has_pending_timer(struct kvm_vcpu *vcpu);
 
-int kvm_irq_delivery_to_apic(struct kvm *kvm, struct kvm_lapic *src,
-			     struct kvm_lapic_irq *irq,
-			     struct dest_map *dest_map);
-
 #endif

arch/x86/kvm/lapic.c

@@ -1249,6 +1249,63 @@ bool kvm_intr_is_single_vcpu_fast(struct kvm *kvm, struct kvm_lapic_irq *irq,
 	return ret;
 }
 
+int kvm_irq_delivery_to_apic(struct kvm *kvm, struct kvm_lapic *src,
+			     struct kvm_lapic_irq *irq, struct dest_map *dest_map)
+{
+	int r = -1;
+	struct kvm_vcpu *vcpu, *lowest = NULL;
+	unsigned long i, dest_vcpu_bitmap[BITS_TO_LONGS(KVM_MAX_VCPUS)];
+	unsigned int dest_vcpus = 0;
+
+	if (kvm_irq_delivery_to_apic_fast(kvm, src, irq, &r, dest_map))
+		return r;
+
+	if (irq->dest_mode == APIC_DEST_PHYSICAL &&
+	    irq->dest_id == 0xff && kvm_lowest_prio_delivery(irq)) {
+		pr_info("apic: phys broadcast and lowest prio\n");
+		irq->delivery_mode = APIC_DM_FIXED;
+	}
+
+	memset(dest_vcpu_bitmap, 0, sizeof(dest_vcpu_bitmap));
+
+	kvm_for_each_vcpu(i, vcpu, kvm) {
+		if (!kvm_apic_present(vcpu))
+			continue;
+
+		if (!kvm_apic_match_dest(vcpu, src, irq->shorthand,
+					irq->dest_id, irq->dest_mode))
+			continue;
+
+		if (!kvm_lowest_prio_delivery(irq)) {
+			if (r < 0)
+				r = 0;
+			r += kvm_apic_set_irq(vcpu, irq, dest_map);
+		} else if (kvm_apic_sw_enabled(vcpu->arch.apic)) {
+			if (!kvm_vector_hashing_enabled()) {
+				if (!lowest)
+					lowest = vcpu;
+				else if (kvm_apic_compare_prio(vcpu, lowest) < 0)
+					lowest = vcpu;
+			} else {
+				__set_bit(i, dest_vcpu_bitmap);
+				dest_vcpus++;
+			}
+		}
+	}
+
+	if (dest_vcpus != 0) {
+		int idx = kvm_vector_to_index(irq->vector, dest_vcpus,
+					dest_vcpu_bitmap, KVM_MAX_VCPUS);
+
+		lowest = kvm_get_vcpu(kvm, idx);
+	}
+
+	if (lowest)
+		r = kvm_apic_set_irq(lowest, irq, dest_map);
+
+	return r;
+}
+
 /*
  * Add a pending IRQ into lapic.
  * Return 1 if successfully added and 0 if discarded.

arch/x86/kvm/lapic.h

@@ -119,6 +119,9 @@ void kvm_inhibit_apic_access_page(struct kvm_vcpu *vcpu);
 
 bool kvm_irq_delivery_to_apic_fast(struct kvm *kvm, struct kvm_lapic *src,
 		struct kvm_lapic_irq *irq, int *r, struct dest_map *dest_map);
+int kvm_irq_delivery_to_apic(struct kvm *kvm, struct kvm_lapic *src,
+			     struct kvm_lapic_irq *irq,
+			     struct dest_map *dest_map);
 void kvm_apic_send_ipi(struct kvm_lapic *apic, u32 icr_low, u32 icr_high);
 
 int kvm_apic_set_base(struct kvm_vcpu *vcpu, u64 value, bool host_initiated);