[thirdparty/linux.git] / virt / kvm / arm / vgic / vgic-init.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (C) 2015, 2016 ARM Ltd.
 */

#include <linux/uaccess.h>
#include <linux/interrupt.h>
#include <linux/cpu.h>
#include <linux/kvm_host.h>
#include <kvm/arm_vgic.h>
#include <asm/kvm_mmu.h>
#include "vgic.h"

/*
 * Initialization rules: there are multiple stages to the vgic
 * initialization, both for the distributor and the CPU interfaces.  The basic
 * idea is that even though the VGIC is not functional or not requested from
 * user space, the critical path of the run loop can still call VGIC functions
 * that just won't do anything, without them having to check additional
 * initialization flags to ensure they don't look at uninitialized data
 * structures.
 *
 * Distributor:
 *
 * - kvm_vgic_early_init(): initialization of static data that doesn't
 *   depend on any sizing information or emulation type. No allocation
 *   is allowed there.
 *
 * - vgic_init(): allocation and initialization of the generic data
 *   structures that depend on sizing information (number of CPUs,
 *   number of interrupts). Also initializes the vcpu specific data
 *   structures. Can be executed lazily for GICv2.
 *
 * CPU Interface:
 *
 * - kvm_vgic_vcpu_init(): initialization of static data that
 *   doesn't depend on any sizing information or emulation type. No
 *   allocation is allowed there.
 */

/* EARLY INIT */

/**
 * kvm_vgic_early_init() - Initialize static VGIC VCPU data structures
 * @kvm: The VM whose VGIC districutor should be initialized
 *
 * Only do initialization of static structures that don't require any
 * allocation or sizing information from userspace.  vgic_init() called
 * kvm_vgic_dist_init() which takes care of the rest.
 */
void kvm_vgic_early_init(struct kvm *kvm)
{
	struct vgic_dist *dist = &kvm->arch.vgic;

	INIT_LIST_HEAD(&dist->lpi_list_head);
	raw_spin_lock_init(&dist->lpi_list_lock);
}

/* CREATION */

/**
 * kvm_vgic_create: triggered by the instantiation of the VGIC device by
 * user space, either through the legacy KVM_CREATE_IRQCHIP ioctl (v2 only)
 * or through the generic KVM_CREATE_DEVICE API ioctl.
 * irqchip_in_kernel() tells you if this function succeeded or not.
 * @kvm: kvm struct pointer
 * @type: KVM_DEV_TYPE_ARM_VGIC_V[23]
 */
int kvm_vgic_create(struct kvm *kvm, u32 type)
{
	int i, vcpu_lock_idx = -1, ret;
	struct kvm_vcpu *vcpu;

	if (irqchip_in_kernel(kvm))
		return -EEXIST;

	/*
	 * This function is also called by the KVM_CREATE_IRQCHIP handler,
	 * which had no chance yet to check the availability of the GICv2
	 * emulation. So check this here again. KVM_CREATE_DEVICE does
	 * the proper checks already.
	 */
	if (type == KVM_DEV_TYPE_ARM_VGIC_V2 &&
		!kvm_vgic_global_state.can_emulate_gicv2)
		return -ENODEV;

	/*
	 * Any time a vcpu is run, vcpu_load is called which tries to grab the
	 * vcpu->mutex.  By grabbing the vcpu->mutex of all VCPUs we ensure
	 * that no other VCPUs are run while we create the vgic.
	 */
	ret = -EBUSY;
	kvm_for_each_vcpu(i, vcpu, kvm) {
		if (!mutex_trylock(&vcpu->mutex))
			goto out_unlock;
		vcpu_lock_idx = i;
	}

	kvm_for_each_vcpu(i, vcpu, kvm) {
		if (vcpu->arch.has_run_once)
			goto out_unlock;
	}
	ret = 0;

	if (type == KVM_DEV_TYPE_ARM_VGIC_V2)
		kvm->arch.max_vcpus = VGIC_V2_MAX_CPUS;
	else
		kvm->arch.max_vcpus = VGIC_V3_MAX_CPUS;

	if (atomic_read(&kvm->online_vcpus) > kvm->arch.max_vcpus) {
		ret = -E2BIG;
		goto out_unlock;
	}

	kvm->arch.vgic.in_kernel = true;
	kvm->arch.vgic.vgic_model = type;

	kvm->arch.vgic.vgic_dist_base = VGIC_ADDR_UNDEF;

	if (type == KVM_DEV_TYPE_ARM_VGIC_V2)
		kvm->arch.vgic.vgic_cpu_base = VGIC_ADDR_UNDEF;
	else
		INIT_LIST_HEAD(&kvm->arch.vgic.rd_regions);

out_unlock:
	for (; vcpu_lock_idx >= 0; vcpu_lock_idx--) {
		vcpu = kvm_get_vcpu(kvm, vcpu_lock_idx);
		mutex_unlock(&vcpu->mutex);
	}
	return ret;
}

/* INIT/DESTROY */

/**
 * kvm_vgic_dist_init: initialize the dist data structures
 * @kvm: kvm struct pointer
 * @nr_spis: number of spis, frozen by caller
 */
static int kvm_vgic_dist_init(struct kvm *kvm, unsigned int nr_spis)
{
	struct vgic_dist *dist = &kvm->arch.vgic;
	struct kvm_vcpu *vcpu0 = kvm_get_vcpu(kvm, 0);
	int i;

	dist->spis = kcalloc(nr_spis, sizeof(struct vgic_irq), GFP_KERNEL);
	if (!dist->spis)
		return  -ENOMEM;

	/*
	 * In the following code we do not take the irq struct lock since
	 * no other action on irq structs can happen while the VGIC is
	 * not initialized yet:
	 * If someone wants to inject an interrupt or does a MMIO access, we
	 * require prior initialization in case of a virtual GICv3 or trigger
	 * initialization when using a virtual GICv2.
	 */
	for (i = 0; i < nr_spis; i++) {
		struct vgic_irq *irq = &dist->spis[i];

		irq->intid = i + VGIC_NR_PRIVATE_IRQS;
		INIT_LIST_HEAD(&irq->ap_list);
		raw_spin_lock_init(&irq->irq_lock);
		irq->vcpu = NULL;
		irq->target_vcpu = vcpu0;
		kref_init(&irq->refcount);
		if (dist->vgic_model == KVM_DEV_TYPE_ARM_VGIC_V2) {
			irq->targets = 0;
			irq->group = 0;
		} else {
			irq->mpidr = 0;
			irq->group = 1;
		}
	}
	return 0;
}

/**
 * kvm_vgic_vcpu_init() - Initialize static VGIC VCPU data
 * structures and register VCPU-specific KVM iodevs
 *
 * @vcpu: pointer to the VCPU being created and initialized
 *
 * Only do initialization, but do not actually enable the
 * VGIC CPU interface
 */
int kvm_vgic_vcpu_init(struct kvm_vcpu *vcpu)
{
	struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
	struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
	int ret = 0;
	int i;

	vgic_cpu->rd_iodev.base_addr = VGIC_ADDR_UNDEF;
	vgic_cpu->sgi_iodev.base_addr = VGIC_ADDR_UNDEF;

	INIT_LIST_HEAD(&vgic_cpu->ap_list_head);
	raw_spin_lock_init(&vgic_cpu->ap_list_lock);

	/*
	 * Enable and configure all SGIs to be edge-triggered and
	 * configure all PPIs as level-triggered.
	 */
	for (i = 0; i < VGIC_NR_PRIVATE_IRQS; i++) {
		struct vgic_irq *irq = &vgic_cpu->private_irqs[i];

		INIT_LIST_HEAD(&irq->ap_list);
		raw_spin_lock_init(&irq->irq_lock);
		irq->intid = i;
		irq->vcpu = NULL;
		irq->target_vcpu = vcpu;
		irq->targets = 1U << vcpu->vcpu_id;
		kref_init(&irq->refcount);
		if (vgic_irq_is_sgi(i)) {
			/* SGIs */
			irq->enabled = 1;
			irq->config = VGIC_CONFIG_EDGE;
		} else {
			/* PPIs */
			irq->config = VGIC_CONFIG_LEVEL;
		}

		if (dist->vgic_model == KVM_DEV_TYPE_ARM_VGIC_V3)
			irq->group = 1;
		else
			irq->group = 0;
	}

	if (!irqchip_in_kernel(vcpu->kvm))
		return 0;

	/*
	 * If we are creating a VCPU with a GICv3 we must also register the
	 * KVM io device for the redistributor that belongs to this VCPU.
	 */
	if (dist->vgic_model == KVM_DEV_TYPE_ARM_VGIC_V3) {
		mutex_lock(&vcpu->kvm->lock);
		ret = vgic_register_redist_iodev(vcpu);
		mutex_unlock(&vcpu->kvm->lock);
	}
	return ret;
}

static void kvm_vgic_vcpu_enable(struct kvm_vcpu *vcpu)
{
	if (kvm_vgic_global_state.type == VGIC_V2)
		vgic_v2_enable(vcpu);
	else
		vgic_v3_enable(vcpu);
}

/*
 * vgic_init: allocates and initializes dist and vcpu data structures
 * depending on two dimensioning parameters:
 * - the number of spis
 * - the number of vcpus
 * The function is generally called when nr_spis has been explicitly set
 * by the guest through the KVM DEVICE API. If not nr_spis is set to 256.
 * vgic_initialized() returns true when this function has succeeded.
 * Must be called with kvm->lock held!
 */
int vgic_init(struct kvm *kvm)
{
	struct vgic_dist *dist = &kvm->arch.vgic;
	struct kvm_vcpu *vcpu;
	int ret = 0, i, idx;

	if (vgic_initialized(kvm))
		return 0;

	/* Are we also in the middle of creating a VCPU? */
	if (kvm->created_vcpus != atomic_read(&kvm->online_vcpus))
		return -EBUSY;

	/* freeze the number of spis */
	if (!dist->nr_spis)
		dist->nr_spis = VGIC_NR_IRQS_LEGACY - VGIC_NR_PRIVATE_IRQS;

	ret = kvm_vgic_dist_init(kvm, dist->nr_spis);
	if (ret)
		goto out;

	/* Initialize groups on CPUs created before the VGIC type was known */
	kvm_for_each_vcpu(idx, vcpu, kvm) {
		struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;

		for (i = 0; i < VGIC_NR_PRIVATE_IRQS; i++) {
			struct vgic_irq *irq = &vgic_cpu->private_irqs[i];
			if (dist->vgic_model == KVM_DEV_TYPE_ARM_VGIC_V3)
				irq->group = 1;
			else
				irq->group = 0;
		}
	}

	if (vgic_has_its(kvm)) {
		ret = vgic_v4_init(kvm);
		if (ret)
			goto out;
	}

	kvm_for_each_vcpu(i, vcpu, kvm)
		kvm_vgic_vcpu_enable(vcpu);

	ret = kvm_vgic_setup_default_irq_routing(kvm);
	if (ret)
		goto out;

	vgic_debug_init(kvm);

	dist->implementation_rev = 2;
	dist->initialized = true;

out:
	return ret;
}

static void kvm_vgic_dist_destroy(struct kvm *kvm)
{
	struct vgic_dist *dist = &kvm->arch.vgic;
	struct vgic_redist_region *rdreg, *next;

	dist->ready = false;
	dist->initialized = false;

	kfree(dist->spis);
	dist->spis = NULL;
	dist->nr_spis = 0;

	if (kvm->arch.vgic.vgic_model == KVM_DEV_TYPE_ARM_VGIC_V3) {
		list_for_each_entry_safe(rdreg, next, &dist->rd_regions, list) {
			list_del(&rdreg->list);
			kfree(rdreg);
		}
		INIT_LIST_HEAD(&dist->rd_regions);
	}

	if (vgic_supports_direct_msis(kvm))
		vgic_v4_teardown(kvm);
}

void kvm_vgic_vcpu_destroy(struct kvm_vcpu *vcpu)
{
	struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;

	INIT_LIST_HEAD(&vgic_cpu->ap_list_head);
}

/* To be called with kvm->lock held */
static void __kvm_vgic_destroy(struct kvm *kvm)
{
	struct kvm_vcpu *vcpu;
	int i;

	vgic_debug_destroy(kvm);

	kvm_vgic_dist_destroy(kvm);

	kvm_for_each_vcpu(i, vcpu, kvm)
		kvm_vgic_vcpu_destroy(vcpu);
}

void kvm_vgic_destroy(struct kvm *kvm)
{
	mutex_lock(&kvm->lock);
	__kvm_vgic_destroy(kvm);
	mutex_unlock(&kvm->lock);
}

/**
 * vgic_lazy_init: Lazy init is only allowed if the GIC exposed to the guest
 * is a GICv2. A GICv3 must be explicitly initialized by the guest using the
 * KVM_DEV_ARM_VGIC_GRP_CTRL KVM_DEVICE group.
 * @kvm: kvm struct pointer
 */
int vgic_lazy_init(struct kvm *kvm)
{
	int ret = 0;

	if (unlikely(!vgic_initialized(kvm))) {
		/*
		 * We only provide the automatic initialization of the VGIC
		 * for the legacy case of a GICv2. Any other type must
		 * be explicitly initialized once setup with the respective
		 * KVM device call.
		 */
		if (kvm->arch.vgic.vgic_model != KVM_DEV_TYPE_ARM_VGIC_V2)
			return -EBUSY;

		mutex_lock(&kvm->lock);
		ret = vgic_init(kvm);
		mutex_unlock(&kvm->lock);
	}

	return ret;
}

/* RESOURCE MAPPING */

/**
 * Map the MMIO regions depending on the VGIC model exposed to the guest
 * called on the first VCPU run.
 * Also map the virtual CPU interface into the VM.
 * v2/v3 derivatives call vgic_init if not already done.
 * vgic_ready() returns true if this function has succeeded.
 * @kvm: kvm struct pointer
 */
int kvm_vgic_map_resources(struct kvm *kvm)
{
	struct vgic_dist *dist = &kvm->arch.vgic;
	int ret = 0;

	mutex_lock(&kvm->lock);
	if (!irqchip_in_kernel(kvm))
		goto out;

	if (dist->vgic_model == KVM_DEV_TYPE_ARM_VGIC_V2)
		ret = vgic_v2_map_resources(kvm);
	else
		ret = vgic_v3_map_resources(kvm);

	if (ret)
		__kvm_vgic_destroy(kvm);

out:
	mutex_unlock(&kvm->lock);
	return ret;
}

/* GENERIC PROBE */

static int vgic_init_cpu_starting(unsigned int cpu)
{
	enable_percpu_irq(kvm_vgic_global_state.maint_irq, 0);
	return 0;
}


static int vgic_init_cpu_dying(unsigned int cpu)
{
	disable_percpu_irq(kvm_vgic_global_state.maint_irq);
	return 0;
}

static irqreturn_t vgic_maintenance_handler(int irq, void *data)
{
	/*
	 * We cannot rely on the vgic maintenance interrupt to be
	 * delivered synchronously. This means we can only use it to
	 * exit the VM, and we perform the handling of EOIed
	 * interrupts on the exit path (see vgic_fold_lr_state).
	 */
	return IRQ_HANDLED;
}

/**
 * kvm_vgic_init_cpu_hardware - initialize the GIC VE hardware
 *
 * For a specific CPU, initialize the GIC VE hardware.
 */
void kvm_vgic_init_cpu_hardware(void)
{
	BUG_ON(preemptible());

	/*
	 * We want to make sure the list registers start out clear so that we
	 * only have the program the used registers.
	 */
	if (kvm_vgic_global_state.type == VGIC_V2)
		vgic_v2_init_lrs();
	else
		kvm_call_hyp(__vgic_v3_init_lrs);
}

/**
 * kvm_vgic_hyp_init: populates the kvm_vgic_global_state variable
 * according to the host GIC model. Accordingly calls either
 * vgic_v2/v3_probe which registers the KVM_DEVICE that can be
 * instantiated by a guest later on .
 */
int kvm_vgic_hyp_init(void)
{
	const struct gic_kvm_info *gic_kvm_info;
	int ret;

	gic_kvm_info = gic_get_kvm_info();
	if (!gic_kvm_info)
		return -ENODEV;

	if (!gic_kvm_info->maint_irq) {
		kvm_err("No vgic maintenance irq\n");
		return -ENXIO;
	}

	switch (gic_kvm_info->type) {
	case GIC_V2:
		ret = vgic_v2_probe(gic_kvm_info);
		break;
	case GIC_V3:
		ret = vgic_v3_probe(gic_kvm_info);
		if (!ret) {
			static_branch_enable(&kvm_vgic_global_state.gicv3_cpuif);
			kvm_info("GIC system register CPU interface enabled\n");
		}
		break;
	default:
		ret = -ENODEV;
	};

	if (ret)
		return ret;

	kvm_vgic_global_state.maint_irq = gic_kvm_info->maint_irq;
	ret = request_percpu_irq(kvm_vgic_global_state.maint_irq,
				 vgic_maintenance_handler,
				 "vgic", kvm_get_running_vcpus());
	if (ret) {
		kvm_err("Cannot register interrupt %d\n",
			kvm_vgic_global_state.maint_irq);
		return ret;
	}

	ret = cpuhp_setup_state(CPUHP_AP_KVM_ARM_VGIC_INIT_STARTING,
				"kvm/arm/vgic:starting",
				vgic_init_cpu_starting, vgic_init_cpu_dying);
	if (ret) {
		kvm_err("Cannot register vgic CPU notifier\n");
		goto out_free_irq;
	}

	kvm_info("vgic interrupt IRQ%d\n", kvm_vgic_global_state.maint_irq);
	return 0;

out_free_irq:
	free_percpu_irq(kvm_vgic_global_state.maint_irq,
			kvm_get_running_vcpus());
	return ret;
}
Commit	Line	Data
caab277b	1	// SPDX-License-Identifier: GPL-2.0-only
90977732 EA	2	/*
90977732 EA	3	* Copyright (C) 2015, 2016 ARM Ltd.
90977732 EA	4	*/
	5
	6	#include <linux/uaccess.h>
	7	#include <linux/interrupt.h>
	8	#include <linux/cpu.h>
	9	#include <linux/kvm_host.h>
	10	#include <kvm/arm_vgic.h>
	11	#include <asm/kvm_mmu.h>
	12	#include "vgic.h"
	13
ad275b8b EA	14	/*
ad275b8b EA	15	* Initialization rules: there are multiple stages to the vgic
966e0149 CD	16	* initialization, both for the distributor and the CPU interfaces. The basic
	17	* idea is that even though the VGIC is not functional or not requested from
	18	* user space, the critical path of the run loop can still call VGIC functions
	19	* that just won't do anything, without them having to check additional
	20	* initialization flags to ensure they don't look at uninitialized data
	21	* structures.
ad275b8b EA	22	*
	23	* Distributor:
	24	*
	25	* - kvm_vgic_early_init(): initialization of static data that doesn't
	26	* depend on any sizing information or emulation type. No allocation
	27	* is allowed there.
	28	*
	29	* - vgic_init(): allocation and initialization of the generic data
	30	* structures that depend on sizing information (number of CPUs,
	31	* number of interrupts). Also initializes the vcpu specific data
	32	* structures. Can be executed lazily for GICv2.
	33	*
	34	* CPU Interface:
	35	*
5ec17fba	36	* - kvm_vgic_vcpu_init(): initialization of static data that
ad275b8b EA	37	* doesn't depend on any sizing information or emulation type. No
	38	* allocation is allowed there.
	39	*/
	40
	41	/* EARLY INIT */
	42
966e0149 CD	43	/**
	44	* kvm_vgic_early_init() - Initialize static VGIC VCPU data structures
	45	* @kvm: The VM whose VGIC districutor should be initialized
	46	*
	47	* Only do initialization of static structures that don't require any
	48	* allocation or sizing information from userspace. vgic_init() called
	49	* kvm_vgic_dist_init() which takes care of the rest.
ad275b8b EA	50	*/
	51	void kvm_vgic_early_init(struct kvm *kvm)
	52	{
966e0149 CD	53	struct vgic_dist *dist = &kvm->arch.vgic;
	54
	55	INIT_LIST_HEAD(&dist->lpi_list_head);
fc3bc475	56	raw_spin_lock_init(&dist->lpi_list_lock);
ad275b8b EA	57	}
ad275b8b EA	58
5e6431da EA	59	/* CREATION */
	60
	61	/**
	62	* kvm_vgic_create: triggered by the instantiation of the VGIC device by
	63	* user space, either through the legacy KVM_CREATE_IRQCHIP ioctl (v2 only)
	64	* or through the generic KVM_CREATE_DEVICE API ioctl.
	65	* irqchip_in_kernel() tells you if this function succeeded or not.
ad275b8b EA	66	* @kvm: kvm struct pointer
ad275b8b EA	67	* @type: KVM_DEV_TYPE_ARM_VGIC_V[23]
5e6431da EA	68	*/
	69	int kvm_vgic_create(struct kvm *kvm, u32 type)
	70	{
	71	int i, vcpu_lock_idx = -1, ret;
	72	struct kvm_vcpu *vcpu;
	73
a28ebea2 CD	74	if (irqchip_in_kernel(kvm))
a28ebea2 CD	75	return -EEXIST;
5e6431da EA	76
	77	/*
	78	* This function is also called by the KVM_CREATE_IRQCHIP handler,
	79	* which had no chance yet to check the availability of the GICv2
	80	* emulation. So check this here again. KVM_CREATE_DEVICE does
	81	* the proper checks already.
	82	*/
	83	if (type == KVM_DEV_TYPE_ARM_VGIC_V2 &&
a28ebea2 CD	84	!kvm_vgic_global_state.can_emulate_gicv2)
a28ebea2 CD	85	return -ENODEV;
5e6431da EA	86
	87	/*
	88	* Any time a vcpu is run, vcpu_load is called which tries to grab the
	89	* vcpu->mutex. By grabbing the vcpu->mutex of all VCPUs we ensure
	90	* that no other VCPUs are run while we create the vgic.
	91	*/
	92	ret = -EBUSY;
	93	kvm_for_each_vcpu(i, vcpu, kvm) {
	94	if (!mutex_trylock(&vcpu->mutex))
	95	goto out_unlock;
	96	vcpu_lock_idx = i;
	97	}
	98
	99	kvm_for_each_vcpu(i, vcpu, kvm) {
	100	if (vcpu->arch.has_run_once)
	101	goto out_unlock;
	102	}
	103	ret = 0;
	104
	105	if (type == KVM_DEV_TYPE_ARM_VGIC_V2)
	106	kvm->arch.max_vcpus = VGIC_V2_MAX_CPUS;
	107	else
	108	kvm->arch.max_vcpus = VGIC_V3_MAX_CPUS;
	109
	110	if (atomic_read(&kvm->online_vcpus) > kvm->arch.max_vcpus) {
	111	ret = -E2BIG;
	112	goto out_unlock;
	113	}
	114
	115	kvm->arch.vgic.in_kernel = true;
	116	kvm->arch.vgic.vgic_model = type;
	117
5e6431da	118	kvm->arch.vgic.vgic_dist_base = VGIC_ADDR_UNDEF;
dbd9733a EA	119
	120	if (type == KVM_DEV_TYPE_ARM_VGIC_V2)
	121	kvm->arch.vgic.vgic_cpu_base = VGIC_ADDR_UNDEF;
	122	else
	123	INIT_LIST_HEAD(&kvm->arch.vgic.rd_regions);
5e6431da EA	124
	125	out_unlock:
	126	for (; vcpu_lock_idx >= 0; vcpu_lock_idx--) {
	127	vcpu = kvm_get_vcpu(kvm, vcpu_lock_idx);
	128	mutex_unlock(&vcpu->mutex);
	129	}
5e6431da EA	130	return ret;
	131	}
	132
ad275b8b EA	133	/* INIT/DESTROY */
	134
	135	/**
	136	* kvm_vgic_dist_init: initialize the dist data structures
	137	* @kvm: kvm struct pointer
	138	* @nr_spis: number of spis, frozen by caller
	139	*/
	140	static int kvm_vgic_dist_init(struct kvm *kvm, unsigned int nr_spis)
	141	{
	142	struct vgic_dist *dist = &kvm->arch.vgic;
	143	struct kvm_vcpu *vcpu0 = kvm_get_vcpu(kvm, 0);
	144	int i;
	145
	146	dist->spis = kcalloc(nr_spis, sizeof(struct vgic_irq), GFP_KERNEL);
	147	if (!dist->spis)
	148	return -ENOMEM;
	149
	150	/*
	151	* In the following code we do not take the irq struct lock since
	152	* no other action on irq structs can happen while the VGIC is
	153	* not initialized yet:
	154	* If someone wants to inject an interrupt or does a MMIO access, we
	155	* require prior initialization in case of a virtual GICv3 or trigger
	156	* initialization when using a virtual GICv2.
	157	*/
	158	for (i = 0; i < nr_spis; i++) {
	159	struct vgic_irq *irq = &dist->spis[i];
	160
	161	irq->intid = i + VGIC_NR_PRIVATE_IRQS;
	162	INIT_LIST_HEAD(&irq->ap_list);
8fa3adb8	163	raw_spin_lock_init(&irq->irq_lock);
ad275b8b EA	164	irq->vcpu = NULL;
ad275b8b EA	165	irq->target_vcpu = vcpu0;
5dd4b924	166	kref_init(&irq->refcount);
8df3c8f3	167	if (dist->vgic_model == KVM_DEV_TYPE_ARM_VGIC_V2) {
ad275b8b	168	irq->targets = 0;
8df3c8f3 CD	169	irq->group = 0;
8df3c8f3 CD	170	} else {
ad275b8b	171	irq->mpidr = 0;
8df3c8f3 CD	172	irq->group = 1;
8df3c8f3 CD	173	}
ad275b8b EA	174	}
	175	return 0;
	176	}
	177
	178	/**
5ec17fba EA	179	* kvm_vgic_vcpu_init() - Initialize static VGIC VCPU data
	180	* structures and register VCPU-specific KVM iodevs
	181	*
1aab6f46	182	* @vcpu: pointer to the VCPU being created and initialized
5ec17fba EA	183	*
	184	* Only do initialization, but do not actually enable the
	185	* VGIC CPU interface
ad275b8b	186	*/
1aab6f46 CD	187	int kvm_vgic_vcpu_init(struct kvm_vcpu *vcpu)
1aab6f46 CD	188	{
5ec17fba	189	struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
1aab6f46	190	struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
5ec17fba EA	191	int ret = 0;
	192	int i;
	193
c011f4ea EA	194	vgic_cpu->rd_iodev.base_addr = VGIC_ADDR_UNDEF;
	195	vgic_cpu->sgi_iodev.base_addr = VGIC_ADDR_UNDEF;
	196
5ec17fba	197	INIT_LIST_HEAD(&vgic_cpu->ap_list_head);
e08d8d29	198	raw_spin_lock_init(&vgic_cpu->ap_list_lock);
5ec17fba EA	199
	200	/*
	201	* Enable and configure all SGIs to be edge-triggered and
	202	* configure all PPIs as level-triggered.
	203	*/
	204	for (i = 0; i < VGIC_NR_PRIVATE_IRQS; i++) {
	205	struct vgic_irq *irq = &vgic_cpu->private_irqs[i];
	206
	207	INIT_LIST_HEAD(&irq->ap_list);
8fa3adb8	208	raw_spin_lock_init(&irq->irq_lock);
5ec17fba EA	209	irq->intid = i;
	210	irq->vcpu = NULL;
	211	irq->target_vcpu = vcpu;
	212	irq->targets = 1U << vcpu->vcpu_id;
	213	kref_init(&irq->refcount);
	214	if (vgic_irq_is_sgi(i)) {
	215	/* SGIs */
	216	irq->enabled = 1;
	217	irq->config = VGIC_CONFIG_EDGE;
	218	} else {
	219	/* PPIs */
	220	irq->config = VGIC_CONFIG_LEVEL;
	221	}
8df3c8f3	222
8df3c8f3 CD	223	if (dist->vgic_model == KVM_DEV_TYPE_ARM_VGIC_V3)
	224	irq->group = 1;
	225	else
	226	irq->group = 0;
5ec17fba	227	}
1aab6f46 CD	228
	229	if (!irqchip_in_kernel(vcpu->kvm))
	230	return 0;
	231
	232	/*
	233	* If we are creating a VCPU with a GICv3 we must also register the
	234	* KVM io device for the redistributor that belongs to this VCPU.
	235	*/
552c9f47 CD	236	if (dist->vgic_model == KVM_DEV_TYPE_ARM_VGIC_V3) {
552c9f47 CD	237	mutex_lock(&vcpu->kvm->lock);
1aab6f46	238	ret = vgic_register_redist_iodev(vcpu);
552c9f47 CD	239	mutex_unlock(&vcpu->kvm->lock);
552c9f47 CD	240	}
1aab6f46 CD	241	return ret;
	242	}
	243
443c3a9e	244	static void kvm_vgic_vcpu_enable(struct kvm_vcpu *vcpu)
ad275b8b	245	{
ad275b8b EA	246	if (kvm_vgic_global_state.type == VGIC_V2)
	247	vgic_v2_enable(vcpu);
	248	else
	249	vgic_v3_enable(vcpu);
	250	}
	251
	252	/*
	253	* vgic_init: allocates and initializes dist and vcpu data structures
	254	* depending on two dimensioning parameters:
	255	* - the number of spis
	256	* - the number of vcpus
	257	* The function is generally called when nr_spis has been explicitly set
	258	* by the guest through the KVM DEVICE API. If not nr_spis is set to 256.
	259	* vgic_initialized() returns true when this function has succeeded.
	260	* Must be called with kvm->lock held!
	261	*/
	262	int vgic_init(struct kvm *kvm)
	263	{
	264	struct vgic_dist *dist = &kvm->arch.vgic;
	265	struct kvm_vcpu *vcpu;
ab2d5eb0	266	int ret = 0, i, idx;
ad275b8b EA	267
	268	if (vgic_initialized(kvm))
	269	return 0;
	270
1d47191d CD	271	/* Are we also in the middle of creating a VCPU? */
	272	if (kvm->created_vcpus != atomic_read(&kvm->online_vcpus))
	273	return -EBUSY;
	274
ad275b8b EA	275	/* freeze the number of spis */
	276	if (!dist->nr_spis)
	277	dist->nr_spis = VGIC_NR_IRQS_LEGACY - VGIC_NR_PRIVATE_IRQS;
	278
	279	ret = kvm_vgic_dist_init(kvm, dist->nr_spis);
	280	if (ret)
	281	goto out;
	282
ab2d5eb0 CD	283	/* Initialize groups on CPUs created before the VGIC type was known */
	284	kvm_for_each_vcpu(idx, vcpu, kvm) {
	285	struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
	286
	287	for (i = 0; i < VGIC_NR_PRIVATE_IRQS; i++) {
	288	struct vgic_irq *irq = &vgic_cpu->private_irqs[i];
	289	if (dist->vgic_model == KVM_DEV_TYPE_ARM_VGIC_V3)
	290	irq->group = 1;
	291	else
	292	irq->group = 0;
	293	}
	294	}
	295
f8f85dc0 CD	296	if (vgic_has_its(kvm)) {
	297	ret = vgic_v4_init(kvm);
	298	if (ret)
	299	goto out;
	300	}
74fe55dc	301
ad275b8b	302	kvm_for_each_vcpu(i, vcpu, kvm)
443c3a9e	303	kvm_vgic_vcpu_enable(vcpu);
ad275b8b	304
180ae7b1 EA	305	ret = kvm_vgic_setup_default_irq_routing(kvm);
	306	if (ret)
	307	goto out;
	308
10f92c4c CD	309	vgic_debug_init(kvm);
10f92c4c CD	310
d53c2c29	311	dist->implementation_rev = 2;
ad275b8b	312	dist->initialized = true;
328e5664	313
ad275b8b EA	314	out:
	315	return ret;
	316	}
	317
	318	static void kvm_vgic_dist_destroy(struct kvm *kvm)
	319	{
	320	struct vgic_dist *dist = &kvm->arch.vgic;
dbd9733a	321	struct vgic_redist_region rdreg, next;
ad275b8b	322
ad275b8b EA	323	dist->ready = false;
	324	dist->initialized = false;
	325
	326	kfree(dist->spis);
9153ab72	327	dist->spis = NULL;
ad275b8b	328	dist->nr_spis = 0;
74fe55dc	329
dbd9733a EA	330	if (kvm->arch.vgic.vgic_model == KVM_DEV_TYPE_ARM_VGIC_V3) {
	331	list_for_each_entry_safe(rdreg, next, &dist->rd_regions, list) {
	332	list_del(&rdreg->list);
	333	kfree(rdreg);
	334	}
	335	INIT_LIST_HEAD(&dist->rd_regions);
	336	}
	337
74fe55dc MZ	338	if (vgic_supports_direct_msis(kvm))
74fe55dc MZ	339	vgic_v4_teardown(kvm);
ad275b8b EA	340	}
	341
	342	void kvm_vgic_vcpu_destroy(struct kvm_vcpu *vcpu)
	343	{
	344	struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
	345
	346	INIT_LIST_HEAD(&vgic_cpu->ap_list_head);
	347	}
	348
1193e6ae MZ	349	/* To be called with kvm->lock held */
1193e6ae MZ	350	static void __kvm_vgic_destroy(struct kvm *kvm)
ad275b8b EA	351	{
	352	struct kvm_vcpu *vcpu;
	353	int i;
	354
10f92c4c CD	355	vgic_debug_destroy(kvm);
10f92c4c CD	356
ad275b8b EA	357	kvm_vgic_dist_destroy(kvm);
	358
	359	kvm_for_each_vcpu(i, vcpu, kvm)
	360	kvm_vgic_vcpu_destroy(vcpu);
	361	}
	362
1193e6ae MZ	363	void kvm_vgic_destroy(struct kvm *kvm)
	364	{
	365	mutex_lock(&kvm->lock);
	366	__kvm_vgic_destroy(kvm);
	367	mutex_unlock(&kvm->lock);
	368	}
	369
ad275b8b EA	370	/**
	371	* vgic_lazy_init: Lazy init is only allowed if the GIC exposed to the guest
	372	* is a GICv2. A GICv3 must be explicitly initialized by the guest using the
	373	* KVM_DEV_ARM_VGIC_GRP_CTRL KVM_DEVICE group.
	374	* @kvm: kvm struct pointer
	375	*/
	376	int vgic_lazy_init(struct kvm *kvm)
	377	{
	378	int ret = 0;
	379
	380	if (unlikely(!vgic_initialized(kvm))) {
	381	/*
	382	* We only provide the automatic initialization of the VGIC
	383	* for the legacy case of a GICv2. Any other type must
	384	* be explicitly initialized once setup with the respective
	385	* KVM device call.
	386	*/
	387	if (kvm->arch.vgic.vgic_model != KVM_DEV_TYPE_ARM_VGIC_V2)
	388	return -EBUSY;
	389
	390	mutex_lock(&kvm->lock);
	391	ret = vgic_init(kvm);
	392	mutex_unlock(&kvm->lock);
	393	}
	394
	395	return ret;
	396	}
	397
b0442ee2 EA	398	/* RESOURCE MAPPING */
	399
	400	/**
	401	* Map the MMIO regions depending on the VGIC model exposed to the guest
	402	* called on the first VCPU run.
	403	* Also map the virtual CPU interface into the VM.
	404	* v2/v3 derivatives call vgic_init if not already done.
	405	* vgic_ready() returns true if this function has succeeded.
	406	* @kvm: kvm struct pointer
	407	*/
	408	int kvm_vgic_map_resources(struct kvm *kvm)
	409	{
	410	struct vgic_dist *dist = &kvm->arch.vgic;
	411	int ret = 0;
	412
	413	mutex_lock(&kvm->lock);
	414	if (!irqchip_in_kernel(kvm))
	415	goto out;
	416
	417	if (dist->vgic_model == KVM_DEV_TYPE_ARM_VGIC_V2)
	418	ret = vgic_v2_map_resources(kvm);
	419	else
	420	ret = vgic_v3_map_resources(kvm);
1193e6ae MZ	421
	422	if (ret)
	423	__kvm_vgic_destroy(kvm);
	424
b0442ee2 EA	425	out:
	426	mutex_unlock(&kvm->lock);
	427	return ret;
	428	}
	429
90977732 EA	430	/* GENERIC PROBE */
90977732 EA	431
15d7e3d3	432	static int vgic_init_cpu_starting(unsigned int cpu)
90977732 EA	433	{
90977732 EA	434	enable_percpu_irq(kvm_vgic_global_state.maint_irq, 0);
15d7e3d3	435	return 0;
90977732 EA	436	}
90977732 EA	437
90977732	438
15d7e3d3 AMG	439	static int vgic_init_cpu_dying(unsigned int cpu)
	440	{
	441	disable_percpu_irq(kvm_vgic_global_state.maint_irq);
	442	return 0;
90977732 EA	443	}
90977732 EA	444
90977732 EA	445	static irqreturn_t vgic_maintenance_handler(int irq, void *data)
	446	{
	447	/*
	448	* We cannot rely on the vgic maintenance interrupt to be
	449	* delivered synchronously. This means we can only use it to
	450	* exit the VM, and we perform the handling of EOIed
c3616a07	451	* interrupts on the exit path (see vgic_fold_lr_state).
90977732 EA	452	*/
	453	return IRQ_HANDLED;
	454	}
	455
5b0d2cc2 CD	456	/**
	457	* kvm_vgic_init_cpu_hardware - initialize the GIC VE hardware
	458	*
	459	* For a specific CPU, initialize the GIC VE hardware.
	460	*/
	461	void kvm_vgic_init_cpu_hardware(void)
	462	{
	463	BUG_ON(preemptible());
	464
	465	/*
	466	* We want to make sure the list registers start out clear so that we
	467	* only have the program the used registers.
	468	*/
	469	if (kvm_vgic_global_state.type == VGIC_V2)
	470	vgic_v2_init_lrs();
	471	else
	472	kvm_call_hyp(__vgic_v3_init_lrs);
	473	}
	474
90977732 EA	475	/**
	476	* kvm_vgic_hyp_init: populates the kvm_vgic_global_state variable
	477	* according to the host GIC model. Accordingly calls either
	478	* vgic_v2/v3_probe which registers the KVM_DEVICE that can be
	479	* instantiated by a guest later on .
	480	*/
	481	int kvm_vgic_hyp_init(void)
	482	{
	483	const struct gic_kvm_info *gic_kvm_info;
	484	int ret;
	485
	486	gic_kvm_info = gic_get_kvm_info();
	487	if (!gic_kvm_info)
	488	return -ENODEV;
	489
	490	if (!gic_kvm_info->maint_irq) {
	491	kvm_err("No vgic maintenance irq\n");
	492	return -ENXIO;
	493	}
	494
	495	switch (gic_kvm_info->type) {
	496	case GIC_V2:
	497	ret = vgic_v2_probe(gic_kvm_info);
	498	break;
	499	case GIC_V3:
	500	ret = vgic_v3_probe(gic_kvm_info);
5a7a8426 VM	501	if (!ret) {
	502	static_branch_enable(&kvm_vgic_global_state.gicv3_cpuif);
	503	kvm_info("GIC system register CPU interface enabled\n");
	504	}
90977732 EA	505	break;
	506	default:
	507	ret = -ENODEV;
	508	};
	509
	510	if (ret)
	511	return ret;
	512
	513	kvm_vgic_global_state.maint_irq = gic_kvm_info->maint_irq;
	514	ret = request_percpu_irq(kvm_vgic_global_state.maint_irq,
	515	vgic_maintenance_handler,
	516	"vgic", kvm_get_running_vcpus());
	517	if (ret) {
	518	kvm_err("Cannot register interrupt %d\n",
	519	kvm_vgic_global_state.maint_irq);
	520	return ret;
	521	}
	522
15d7e3d3	523	ret = cpuhp_setup_state(CPUHP_AP_KVM_ARM_VGIC_INIT_STARTING,
73c1b41e	524	"kvm/arm/vgic:starting",
15d7e3d3	525	vgic_init_cpu_starting, vgic_init_cpu_dying);
90977732 EA	526	if (ret) {
	527	kvm_err("Cannot register vgic CPU notifier\n");
	528	goto out_free_irq;
	529	}
	530
90977732 EA	531	kvm_info("vgic interrupt IRQ%d\n", kvm_vgic_global_state.maint_irq);
	532	return 0;
	533
	534	out_free_irq:
	535	free_percpu_irq(kvm_vgic_global_state.maint_irq,
	536	kvm_get_running_vcpus());
	537	return ret;
	538	}