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

/*
 * Copyright (C) 2015, 2016 ARM Ltd.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#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.
 *
 * 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_cpu_early_init(): initialization of static data that
 *   doesn't depend on any sizing information or emulation type. No
 *   allocation is allowed there.
 */

/* EARLY INIT */

/*
 * Those 2 functions should not be needed anymore but they
 * still are called from arm.c
 */
void kvm_vgic_early_init(struct kvm *kvm)
{
}

void kvm_vgic_vcpu_early_init(struct kvm_vcpu *vcpu)
{
}

/* 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;

	mutex_lock(&kvm->lock);

	if (irqchip_in_kernel(kvm)) {
		ret = -EEXIST;
		goto out;
	}

	/*
	 * 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) {
		ret = -ENODEV;
		goto out;
	}

	/*
	 * 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_vgic_global_state.vctrl_base is set on vgic probe (kvm_arch_init)
	 * it is stored in distributor struct for asm save/restore purpose
	 */
	kvm->arch.vgic.vctrl_base = kvm_vgic_global_state.vctrl_base;

	kvm->arch.vgic.vgic_dist_base = VGIC_ADDR_UNDEF;
	kvm->arch.vgic.vgic_cpu_base = VGIC_ADDR_UNDEF;
	kvm->arch.vgic.vgic_redist_base = VGIC_ADDR_UNDEF;

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

out:
	mutex_unlock(&kvm->lock);
	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;

	INIT_LIST_HEAD(&dist->lpi_list_head);
	spin_lock_init(&dist->lpi_list_lock);

	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);
		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;
		else
			irq->mpidr = 0;
	}
	return 0;
}

/**
 * kvm_vgic_vcpu_init: initialize the vcpu data structures and
 * enable the VCPU interface
 * @vcpu: the VCPU which's VGIC should be initialized
 */
static void kvm_vgic_vcpu_init(struct kvm_vcpu *vcpu)
{
	struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
	int i;

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

	if (vgic_initialized(kvm))
		return 0;

	/* 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;

	if (vgic_has_its(kvm))
		dist->msis_require_devid = true;

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

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

	dist->initialized = true;
out:
	return ret;
}

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

	mutex_lock(&kvm->lock);

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

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

	mutex_unlock(&kvm->lock);
}

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);
}

void kvm_vgic_destroy(struct kvm *kvm)
{
	struct kvm_vcpu *vcpu;
	int i;

	kvm_vgic_dist_destroy(kvm);

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

/**
 * 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);
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_process_maintenance).
	 */
	return IRQ_HANDLED;
}

/**
 * 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);
		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,
				"AP_KVM_ARM_VGIC_INIT_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
90977732 EA	1	/*
	2	* Copyright (C) 2015, 2016 ARM Ltd.
	3	*
	4	* This program is free software; you can redistribute it and/or modify
	5	* it under the terms of the GNU General Public License version 2 as
	6	* published by the Free Software Foundation.
	7	*
	8	* This program is distributed in the hope that it will be useful,
	9	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	10	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	11	* GNU General Public License for more details.
	12	*
	13	* You should have received a copy of the GNU General Public License
	14	* along with this program. If not, see <http://www.gnu.org/licenses/>.
	15	*/
	16
	17	#include <linux/uaccess.h>
	18	#include <linux/interrupt.h>
	19	#include <linux/cpu.h>
	20	#include <linux/kvm_host.h>
	21	#include <kvm/arm_vgic.h>
	22	#include <asm/kvm_mmu.h>
	23	#include "vgic.h"
	24
ad275b8b EA	25	/*
	26	* Initialization rules: there are multiple stages to the vgic
	27	* initialization, both for the distributor and the CPU interfaces.
	28	*
	29	* Distributor:
	30	*
	31	* - kvm_vgic_early_init(): initialization of static data that doesn't
	32	* depend on any sizing information or emulation type. No allocation
	33	* is allowed there.
	34	*
	35	* - vgic_init(): allocation and initialization of the generic data
	36	* structures that depend on sizing information (number of CPUs,
	37	* number of interrupts). Also initializes the vcpu specific data
	38	* structures. Can be executed lazily for GICv2.
	39	*
	40	* CPU Interface:
	41	*
	42	* - kvm_vgic_cpu_early_init(): initialization of static data that
	43	* doesn't depend on any sizing information or emulation type. No
	44	* allocation is allowed there.
	45	*/
	46
	47	/* EARLY INIT */
	48
	49	/*
	50	* Those 2 functions should not be needed anymore but they
	51	* still are called from arm.c
	52	*/
	53	void kvm_vgic_early_init(struct kvm *kvm)
	54	{
	55	}
	56
	57	void kvm_vgic_vcpu_early_init(struct kvm_vcpu *vcpu)
	58	{
	59	}
	60
5e6431da EA	61	/* CREATION */
	62
	63	/**
	64	* kvm_vgic_create: triggered by the instantiation of the VGIC device by
	65	* user space, either through the legacy KVM_CREATE_IRQCHIP ioctl (v2 only)
	66	* or through the generic KVM_CREATE_DEVICE API ioctl.
	67	* irqchip_in_kernel() tells you if this function succeeded or not.
ad275b8b EA	68	* @kvm: kvm struct pointer
ad275b8b EA	69	* @type: KVM_DEV_TYPE_ARM_VGIC_V[23]
5e6431da EA	70	*/
	71	int kvm_vgic_create(struct kvm *kvm, u32 type)
	72	{
	73	int i, vcpu_lock_idx = -1, ret;
	74	struct kvm_vcpu *vcpu;
	75
	76	mutex_lock(&kvm->lock);
	77
	78	if (irqchip_in_kernel(kvm)) {
	79	ret = -EEXIST;
	80	goto out;
	81	}
	82
	83	/*
	84	* This function is also called by the KVM_CREATE_IRQCHIP handler,
	85	* which had no chance yet to check the availability of the GICv2
	86	* emulation. So check this here again. KVM_CREATE_DEVICE does
	87	* the proper checks already.
	88	*/
	89	if (type == KVM_DEV_TYPE_ARM_VGIC_V2 &&
	90	!kvm_vgic_global_state.can_emulate_gicv2) {
	91	ret = -ENODEV;
	92	goto out;
	93	}
	94
	95	/*
	96	* Any time a vcpu is run, vcpu_load is called which tries to grab the
	97	* vcpu->mutex. By grabbing the vcpu->mutex of all VCPUs we ensure
	98	* that no other VCPUs are run while we create the vgic.
	99	*/
	100	ret = -EBUSY;
	101	kvm_for_each_vcpu(i, vcpu, kvm) {
	102	if (!mutex_trylock(&vcpu->mutex))
	103	goto out_unlock;
	104	vcpu_lock_idx = i;
	105	}
	106
	107	kvm_for_each_vcpu(i, vcpu, kvm) {
	108	if (vcpu->arch.has_run_once)
	109	goto out_unlock;
	110	}
	111	ret = 0;
	112
	113	if (type == KVM_DEV_TYPE_ARM_VGIC_V2)
	114	kvm->arch.max_vcpus = VGIC_V2_MAX_CPUS;
	115	else
	116	kvm->arch.max_vcpus = VGIC_V3_MAX_CPUS;
	117
	118	if (atomic_read(&kvm->online_vcpus) > kvm->arch.max_vcpus) {
	119	ret = -E2BIG;
	120	goto out_unlock;
	121	}
	122
	123	kvm->arch.vgic.in_kernel = true;
	124	kvm->arch.vgic.vgic_model = type;
	125
	126	/*
	127	* kvm_vgic_global_state.vctrl_base is set on vgic probe (kvm_arch_init)
	128	* it is stored in distributor struct for asm save/restore purpose
	129	*/
	130	kvm->arch.vgic.vctrl_base = kvm_vgic_global_state.vctrl_base;
	131
	132	kvm->arch.vgic.vgic_dist_base = VGIC_ADDR_UNDEF;
	133	kvm->arch.vgic.vgic_cpu_base = VGIC_ADDR_UNDEF;
134	kvm->arch.vgic.vgic_redist_base = VGIC_ADDR_UNDEF;
135
136	out_unlock:
137	for (; vcpu_lock_idx >= 0; vcpu_lock_idx--) {
138	vcpu = kvm_get_vcpu(kvm, vcpu_lock_idx);
139	mutex_unlock(&vcpu->mutex);
140	}
141
142	out:
143	mutex_unlock(&kvm->lock);
144	return ret;
145	}
146
ad275b8b EA	147	/* INIT/DESTROY */
	148
	149	/**
	150	* kvm_vgic_dist_init: initialize the dist data structures
	151	* @kvm: kvm struct pointer
	152	* @nr_spis: number of spis, frozen by caller
	153	*/
	154	static int kvm_vgic_dist_init(struct kvm *kvm, unsigned int nr_spis)
	155	{
	156	struct vgic_dist *dist = &kvm->arch.vgic;
	157	struct kvm_vcpu *vcpu0 = kvm_get_vcpu(kvm, 0);
	158	int i;
	159
3802411d AP	160	INIT_LIST_HEAD(&dist->lpi_list_head);
	161	spin_lock_init(&dist->lpi_list_lock);
	162
ad275b8b EA	163	dist->spis = kcalloc(nr_spis, sizeof(struct vgic_irq), GFP_KERNEL);
	164	if (!dist->spis)
	165	return -ENOMEM;
	166
	167	/*
	168	* In the following code we do not take the irq struct lock since
	169	* no other action on irq structs can happen while the VGIC is
	170	* not initialized yet:
	171	* If someone wants to inject an interrupt or does a MMIO access, we
	172	* require prior initialization in case of a virtual GICv3 or trigger
	173	* initialization when using a virtual GICv2.
	174	*/
	175	for (i = 0; i < nr_spis; i++) {
	176	struct vgic_irq *irq = &dist->spis[i];
	177
	178	irq->intid = i + VGIC_NR_PRIVATE_IRQS;
	179	INIT_LIST_HEAD(&irq->ap_list);
	180	spin_lock_init(&irq->irq_lock);
	181	irq->vcpu = NULL;
	182	irq->target_vcpu = vcpu0;
5dd4b924	183	kref_init(&irq->refcount);
ad275b8b EA	184	if (dist->vgic_model == KVM_DEV_TYPE_ARM_VGIC_V2)
	185	irq->targets = 0;
	186	else
	187	irq->mpidr = 0;
	188	}
	189	return 0;
	190	}
	191
	192	/**
	193	* kvm_vgic_vcpu_init: initialize the vcpu data structures and
	194	* enable the VCPU interface
	195	* @vcpu: the VCPU which's VGIC should be initialized
	196	*/
	197	static void kvm_vgic_vcpu_init(struct kvm_vcpu *vcpu)
	198	{
	199	struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
	200	int i;
	201
	202	INIT_LIST_HEAD(&vgic_cpu->ap_list_head);
	203	spin_lock_init(&vgic_cpu->ap_list_lock);
	204
	205	/*
	206	* Enable and configure all SGIs to be edge-triggered and
	207	* configure all PPIs as level-triggered.
	208	*/
	209	for (i = 0; i < VGIC_NR_PRIVATE_IRQS; i++) {
	210	struct vgic_irq *irq = &vgic_cpu->private_irqs[i];
	211
	212	INIT_LIST_HEAD(&irq->ap_list);
	213	spin_lock_init(&irq->irq_lock);
	214	irq->intid = i;
	215	irq->vcpu = NULL;
	216	irq->target_vcpu = vcpu;
	217	irq->targets = 1U << vcpu->vcpu_id;
5dd4b924	218	kref_init(&irq->refcount);
ad275b8b EA	219	if (vgic_irq_is_sgi(i)) {
	220	/* SGIs */
	221	irq->enabled = 1;
	222	irq->config = VGIC_CONFIG_EDGE;
	223	} else {
	224	/* PPIs */
	225	irq->config = VGIC_CONFIG_LEVEL;
	226	}
	227	}
	228	if (kvm_vgic_global_state.type == VGIC_V2)
	229	vgic_v2_enable(vcpu);
	230	else
	231	vgic_v3_enable(vcpu);
	232	}
	233
	234	/*
	235	* vgic_init: allocates and initializes dist and vcpu data structures
	236	* depending on two dimensioning parameters:
	237	* - the number of spis
	238	* - the number of vcpus
	239	* The function is generally called when nr_spis has been explicitly set
	240	* by the guest through the KVM DEVICE API. If not nr_spis is set to 256.
	241	* vgic_initialized() returns true when this function has succeeded.
	242	* Must be called with kvm->lock held!
	243	*/
	244	int vgic_init(struct kvm *kvm)
	245	{
	246	struct vgic_dist *dist = &kvm->arch.vgic;
	247	struct kvm_vcpu *vcpu;
	248	int ret = 0, i;
	249
	250	if (vgic_initialized(kvm))
	251	return 0;
	252
	253	/* freeze the number of spis */
	254	if (!dist->nr_spis)
	255	dist->nr_spis = VGIC_NR_IRQS_LEGACY - VGIC_NR_PRIVATE_IRQS;
	256
	257	ret = kvm_vgic_dist_init(kvm, dist->nr_spis);
	258	if (ret)
	259	goto out;
	260
0e4e82f1 AP	261	if (vgic_has_its(kvm))
	262	dist->msis_require_devid = true;
	263
ad275b8b EA	264	kvm_for_each_vcpu(i, vcpu, kvm)
	265	kvm_vgic_vcpu_init(vcpu);
	266
180ae7b1 EA	267	ret = kvm_vgic_setup_default_irq_routing(kvm);
	268	if (ret)
	269	goto out;
	270
ad275b8b EA	271	dist->initialized = true;
	272	out:
	273	return ret;
	274	}
	275
	276	static void kvm_vgic_dist_destroy(struct kvm *kvm)
	277	{
	278	struct vgic_dist *dist = &kvm->arch.vgic;
	279
	280	mutex_lock(&kvm->lock);
	281
	282	dist->ready = false;
	283	dist->initialized = false;
	284
	285	kfree(dist->spis);
ad275b8b EA	286	dist->nr_spis = 0;
	287
	288	mutex_unlock(&kvm->lock);
	289	}
	290
	291	void kvm_vgic_vcpu_destroy(struct kvm_vcpu *vcpu)
	292	{
	293	struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
	294
	295	INIT_LIST_HEAD(&vgic_cpu->ap_list_head);
	296	}
	297
	298	void kvm_vgic_destroy(struct kvm *kvm)
	299	{
	300	struct kvm_vcpu *vcpu;
	301	int i;
	302
	303	kvm_vgic_dist_destroy(kvm);
	304
	305	kvm_for_each_vcpu(i, vcpu, kvm)
	306	kvm_vgic_vcpu_destroy(vcpu);
	307	}
	308
	309	/**
	310	* vgic_lazy_init: Lazy init is only allowed if the GIC exposed to the guest
	311	* is a GICv2. A GICv3 must be explicitly initialized by the guest using the
	312	* KVM_DEV_ARM_VGIC_GRP_CTRL KVM_DEVICE group.
	313	* @kvm: kvm struct pointer
	314	*/
	315	int vgic_lazy_init(struct kvm *kvm)
	316	{
	317	int ret = 0;
	318
	319	if (unlikely(!vgic_initialized(kvm))) {
	320	/*
	321	* We only provide the automatic initialization of the VGIC
	322	* for the legacy case of a GICv2. Any other type must
	323	* be explicitly initialized once setup with the respective
	324	* KVM device call.
	325	*/
	326	if (kvm->arch.vgic.vgic_model != KVM_DEV_TYPE_ARM_VGIC_V2)
	327	return -EBUSY;
	328
	329	mutex_lock(&kvm->lock);
	330	ret = vgic_init(kvm);
	331	mutex_unlock(&kvm->lock);
	332	}
	333
	334	return ret;
	335	}
	336
b0442ee2 EA	337	/* RESOURCE MAPPING */
	338
	339	/**
	340	* Map the MMIO regions depending on the VGIC model exposed to the guest
	341	* called on the first VCPU run.
	342	* Also map the virtual CPU interface into the VM.
	343	* v2/v3 derivatives call vgic_init if not already done.
	344	* vgic_ready() returns true if this function has succeeded.
	345	* @kvm: kvm struct pointer
	346	*/
	347	int kvm_vgic_map_resources(struct kvm *kvm)
	348	{
	349	struct vgic_dist *dist = &kvm->arch.vgic;
	350	int ret = 0;
	351
	352	mutex_lock(&kvm->lock);
	353	if (!irqchip_in_kernel(kvm))
	354	goto out;
	355
	356	if (dist->vgic_model == KVM_DEV_TYPE_ARM_VGIC_V2)
	357	ret = vgic_v2_map_resources(kvm);
	358	else
	359	ret = vgic_v3_map_resources(kvm);
	360	out:
	361	mutex_unlock(&kvm->lock);
	362	return ret;
	363	}
	364
90977732 EA	365	/* GENERIC PROBE */
90977732 EA	366
15d7e3d3	367	static int vgic_init_cpu_starting(unsigned int cpu)
90977732 EA	368	{
90977732 EA	369	enable_percpu_irq(kvm_vgic_global_state.maint_irq, 0);
15d7e3d3	370	return 0;
90977732 EA	371	}
90977732 EA	372
90977732	373
15d7e3d3 AMG	374	static int vgic_init_cpu_dying(unsigned int cpu)
	375	{
	376	disable_percpu_irq(kvm_vgic_global_state.maint_irq);
	377	return 0;
90977732 EA	378	}
90977732 EA	379
90977732 EA	380	static irqreturn_t vgic_maintenance_handler(int irq, void *data)
	381	{
	382	/*
	383	* We cannot rely on the vgic maintenance interrupt to be
	384	* delivered synchronously. This means we can only use it to
	385	* exit the VM, and we perform the handling of EOIed
	386	* interrupts on the exit path (see vgic_process_maintenance).
	387	*/
	388	return IRQ_HANDLED;
	389	}
	390
	391	/**
	392	* kvm_vgic_hyp_init: populates the kvm_vgic_global_state variable
	393	* according to the host GIC model. Accordingly calls either
	394	* vgic_v2/v3_probe which registers the KVM_DEVICE that can be
	395	* instantiated by a guest later on .
	396	*/
	397	int kvm_vgic_hyp_init(void)
	398	{
	399	const struct gic_kvm_info *gic_kvm_info;
	400	int ret;
	401
	402	gic_kvm_info = gic_get_kvm_info();
	403	if (!gic_kvm_info)
	404	return -ENODEV;
	405
	406	if (!gic_kvm_info->maint_irq) {
	407	kvm_err("No vgic maintenance irq\n");
	408	return -ENXIO;
	409	}
	410
	411	switch (gic_kvm_info->type) {
	412	case GIC_V2:
	413	ret = vgic_v2_probe(gic_kvm_info);
	414	break;
	415	case GIC_V3:
	416	ret = vgic_v3_probe(gic_kvm_info);
	417	break;
	418	default:
	419	ret = -ENODEV;
	420	};
	421
	422	if (ret)
	423	return ret;
	424
	425	kvm_vgic_global_state.maint_irq = gic_kvm_info->maint_irq;
	426	ret = request_percpu_irq(kvm_vgic_global_state.maint_irq,
	427	vgic_maintenance_handler,
	428	"vgic", kvm_get_running_vcpus());
	429	if (ret) {
	430	kvm_err("Cannot register interrupt %d\n",
	431	kvm_vgic_global_state.maint_irq);
	432	return ret;
	433	}
	434
15d7e3d3 AMG	435	ret = cpuhp_setup_state(CPUHP_AP_KVM_ARM_VGIC_INIT_STARTING,
	436	"AP_KVM_ARM_VGIC_INIT_STARTING",
	437	vgic_init_cpu_starting, vgic_init_cpu_dying);
90977732 EA	438	if (ret) {
	439	kvm_err("Cannot register vgic CPU notifier\n");
	440	goto out_free_irq;
	441	}
	442
90977732 EA	443	kvm_info("vgic interrupt IRQ%d\n", kvm_vgic_global_state.maint_irq);
	444	return 0;
	445
	446	out_free_irq:
	447	free_percpu_irq(kvm_vgic_global_state.maint_irq,
	448	kvm_get_running_vcpus());
	449	return ret;
	450	}