KVM: arm64: vgic: Make kvm_vgic_inject_irq() take a vcpu pointer

Passing a vcpu_id to kvm_vgic_inject_irq() is silly for two reasons:

- we often confuse vcpu_id and vcpu_idx
- we eventually have to convert it back to a vcpu
- we can't count

Instead, pass a vcpu pointer, which is unambiguous. A NULL vcpu
is also allowed for interrupts that are not private to a vcpu
(such as SPIs).

Reviewed-by: Zenghui Yu <yuzenghui@huawei.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20230927090911.3355209-2-maz@kernel.org
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>

Author: Marc Zyngier

arch/arm64/kvm/arch_timer.c

@@ -458,7 +458,7 @@ static void kvm_timer_update_irq(struct kvm_vcpu *vcpu, bool new_level,
 				   timer_ctx->irq.level);
 
 	if (!userspace_irqchip(vcpu->kvm)) {
-		ret = kvm_vgic_inject_irq(vcpu->kvm, vcpu->vcpu_id,
+		ret = kvm_vgic_inject_irq(vcpu->kvm, vcpu,
 					  timer_irq(timer_ctx),
 					  timer_ctx->irq.level,
 					  timer_ctx);

arch/arm64/kvm/arm.c

@@ -1134,27 +1134,23 @@ int kvm_vm_ioctl_irq_line(struct kvm *kvm, struct kvm_irq_level *irq_level,
 			  bool line_status)
 {
 	u32 irq = irq_level->irq;
-	unsigned int irq_type, vcpu_idx, irq_num;
-	int nrcpus = atomic_read(&kvm->online_vcpus);
+	unsigned int irq_type, vcpu_id, irq_num;
 	struct kvm_vcpu *vcpu = NULL;
 	bool level = irq_level->level;
 
 	irq_type = (irq >> KVM_ARM_IRQ_TYPE_SHIFT) & KVM_ARM_IRQ_TYPE_MASK;
-	vcpu_idx = (irq >> KVM_ARM_IRQ_VCPU_SHIFT) & KVM_ARM_IRQ_VCPU_MASK;
-	vcpu_idx += ((irq >> KVM_ARM_IRQ_VCPU2_SHIFT) & KVM_ARM_IRQ_VCPU2_MASK) * (KVM_ARM_IRQ_VCPU_MASK + 1);
+	vcpu_id = (irq >> KVM_ARM_IRQ_VCPU_SHIFT) & KVM_ARM_IRQ_VCPU_MASK;
+	vcpu_id += ((irq >> KVM_ARM_IRQ_VCPU2_SHIFT) & KVM_ARM_IRQ_VCPU2_MASK) * (KVM_ARM_IRQ_VCPU_MASK + 1);
 	irq_num = (irq >> KVM_ARM_IRQ_NUM_SHIFT) & KVM_ARM_IRQ_NUM_MASK;
 
-	trace_kvm_irq_line(irq_type, vcpu_idx, irq_num, irq_level->level);
+	trace_kvm_irq_line(irq_type, vcpu_id, irq_num, irq_level->level);
 
 	switch (irq_type) {
 	case KVM_ARM_IRQ_TYPE_CPU:
 		if (irqchip_in_kernel(kvm))
 			return -ENXIO;
 
-		if (vcpu_idx >= nrcpus)
-			return -EINVAL;
-
-		vcpu = kvm_get_vcpu(kvm, vcpu_idx);
+		vcpu = kvm_get_vcpu_by_id(kvm, vcpu_id);
 		if (!vcpu)
 			return -EINVAL;
 
@@ -1166,25 +1162,22 @@ int kvm_vm_ioctl_irq_line(struct kvm *kvm, struct kvm_irq_level *irq_level,
 		if (!irqchip_in_kernel(kvm))
 			return -ENXIO;
 
-		if (vcpu_idx >= nrcpus)
-			return -EINVAL;
-
-		vcpu = kvm_get_vcpu(kvm, vcpu_idx);
+		vcpu = kvm_get_vcpu_by_id(kvm, vcpu_id);
 		if (!vcpu)
 			return -EINVAL;
 
 		if (irq_num < VGIC_NR_SGIS || irq_num >= VGIC_NR_PRIVATE_IRQS)
 			return -EINVAL;
 
-		return kvm_vgic_inject_irq(kvm, vcpu->vcpu_id, irq_num, level, NULL);
+		return kvm_vgic_inject_irq(kvm, vcpu, irq_num, level, NULL);
 	case KVM_ARM_IRQ_TYPE_SPI:
 		if (!irqchip_in_kernel(kvm))
 			return -ENXIO;
 
 		if (irq_num < VGIC_NR_PRIVATE_IRQS)
 			return -EINVAL;
 
-		return kvm_vgic_inject_irq(kvm, 0, irq_num, level, NULL);
+		return kvm_vgic_inject_irq(kvm, NULL, irq_num, level, NULL);
 	}
 
 	return -EINVAL;

arch/arm64/kvm/pmu-emul.c

@@ -348,7 +348,7 @@ static void kvm_pmu_update_state(struct kvm_vcpu *vcpu)
 	pmu->irq_level = overflow;
 
 	if (likely(irqchip_in_kernel(vcpu->kvm))) {
-		int ret = kvm_vgic_inject_irq(vcpu->kvm, vcpu->vcpu_id,
+		int ret = kvm_vgic_inject_irq(vcpu->kvm, vcpu,
 					      pmu->irq_num, overflow, pmu);
 		WARN_ON(ret);
 	}

arch/arm64/kvm/vgic/vgic-irqfd.c

@@ -23,7 +23,7 @@ static int vgic_irqfd_set_irq(struct kvm_kernel_irq_routing_entry *e,
 
 	if (!vgic_valid_spi(kvm, spi_id))
 		return -EINVAL;
-	return kvm_vgic_inject_irq(kvm, 0, spi_id, level, NULL);
+	return kvm_vgic_inject_irq(kvm, NULL, spi_id, level, NULL);
 }
 
 /**

arch/arm64/kvm/vgic/vgic.c

@@ -422,7 +422,7 @@ bool vgic_queue_irq_unlock(struct kvm *kvm, struct vgic_irq *irq,
 /**
  * kvm_vgic_inject_irq - Inject an IRQ from a device to the vgic
  * @kvm:     The VM structure pointer
- * @cpuid:   The CPU for PPIs
+ * @vcpu:    The CPU for PPIs or NULL for global interrupts
  * @intid:   The INTID to inject a new state to.
  * @level:   Edge-triggered:  true:  to trigger the interrupt
  *			      false: to ignore the call
@@ -436,24 +436,22 @@ bool vgic_queue_irq_unlock(struct kvm *kvm, struct vgic_irq *irq,
  * level-sensitive interrupts.  You can think of the level parameter as 1
  * being HIGH and 0 being LOW and all devices being active-HIGH.
  */
-int kvm_vgic_inject_irq(struct kvm *kvm, int cpuid, unsigned int intid,
-			bool level, void *owner)
+int kvm_vgic_inject_irq(struct kvm *kvm, struct kvm_vcpu *vcpu,
+			unsigned int intid, bool level, void *owner)
 {
-	struct kvm_vcpu *vcpu;
 	struct vgic_irq *irq;
 	unsigned long flags;
 	int ret;
 
-	trace_vgic_update_irq_pending(cpuid, intid, level);
-
 	ret = vgic_lazy_init(kvm);
 	if (ret)
 		return ret;
 
-	vcpu = kvm_get_vcpu(kvm, cpuid);
 	if (!vcpu && intid < VGIC_NR_PRIVATE_IRQS)
 		return -EINVAL;
 
+	trace_vgic_update_irq_pending(vcpu ? vcpu->vcpu_idx : 0, intid, level);
+
 	irq = vgic_get_irq(kvm, vcpu, intid);
 	if (!irq)
 		return -EINVAL;

include/kvm/arm_vgic.h

@@ -375,8 +375,8 @@ int kvm_vgic_map_resources(struct kvm *kvm);
 int kvm_vgic_hyp_init(void);
 void kvm_vgic_init_cpu_hardware(void);
 
-int kvm_vgic_inject_irq(struct kvm *kvm, int cpuid, unsigned int intid,
-			bool level, void *owner);
+int kvm_vgic_inject_irq(struct kvm *kvm, struct kvm_vcpu *vcpu,
+			unsigned int intid, bool level, void *owner);
 int kvm_vgic_map_phys_irq(struct kvm_vcpu *vcpu, unsigned int host_irq,
 			  u32 vintid, struct irq_ops *ops);
 int kvm_vgic_unmap_phys_irq(struct kvm_vcpu *vcpu, unsigned int vintid);