vgic-its.c 47.2 KB
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/*
 * GICv3 ITS emulation
 *
 * Copyright (C) 2015,2016 ARM Ltd.
 * Author: Andre Przywara <andre.przywara@arm.com>
 *
 * 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/cpu.h>
#include <linux/kvm.h>
#include <linux/kvm_host.h>
#include <linux/interrupt.h>
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#include <linux/list.h>
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#include <linux/uaccess.h>
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#include <linux/irqchip/arm-gic-v3.h>

#include <asm/kvm_emulate.h>
#include <asm/kvm_arm.h>
#include <asm/kvm_mmu.h>

#include "vgic.h"
#include "vgic-mmio.h"

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static int vgic_its_save_tables_v0(struct vgic_its *its);
static int vgic_its_restore_tables_v0(struct vgic_its *its);
static int vgic_its_commit_v0(struct vgic_its *its);

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/*
 * Creates a new (reference to a) struct vgic_irq for a given LPI.
 * If this LPI is already mapped on another ITS, we increase its refcount
 * and return a pointer to the existing structure.
 * If this is a "new" LPI, we allocate and initialize a new struct vgic_irq.
 * This function returns a pointer to the _unlocked_ structure.
 */
static struct vgic_irq *vgic_add_lpi(struct kvm *kvm, u32 intid)
{
	struct vgic_dist *dist = &kvm->arch.vgic;
	struct vgic_irq *irq = vgic_get_irq(kvm, NULL, intid), *oldirq;

	/* In this case there is no put, since we keep the reference. */
	if (irq)
		return irq;

	irq = kzalloc(sizeof(struct vgic_irq), GFP_KERNEL);
	if (!irq)
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		return ERR_PTR(-ENOMEM);
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	INIT_LIST_HEAD(&irq->lpi_list);
	INIT_LIST_HEAD(&irq->ap_list);
	spin_lock_init(&irq->irq_lock);

	irq->config = VGIC_CONFIG_EDGE;
	kref_init(&irq->refcount);
	irq->intid = intid;

	spin_lock(&dist->lpi_list_lock);

	/*
	 * There could be a race with another vgic_add_lpi(), so we need to
	 * check that we don't add a second list entry with the same LPI.
	 */
	list_for_each_entry(oldirq, &dist->lpi_list_head, lpi_list) {
		if (oldirq->intid != intid)
			continue;

		/* Someone was faster with adding this LPI, lets use that. */
		kfree(irq);
		irq = oldirq;

		/*
		 * This increases the refcount, the caller is expected to
		 * call vgic_put_irq() on the returned pointer once it's
		 * finished with the IRQ.
		 */
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		vgic_get_irq_kref(irq);
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		goto out_unlock;
	}

	list_add_tail(&irq->lpi_list, &dist->lpi_list_head);
	dist->lpi_list_count++;

out_unlock:
	spin_unlock(&dist->lpi_list_lock);

	return irq;
}

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struct its_device {
	struct list_head dev_list;

	/* the head for the list of ITTEs */
	struct list_head itt_head;
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	u32 num_eventid_bits;
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	u32 device_id;
};

#define COLLECTION_NOT_MAPPED ((u32)~0)

struct its_collection {
	struct list_head coll_list;

	u32 collection_id;
	u32 target_addr;
};

#define its_is_collection_mapped(coll) ((coll) && \
				((coll)->target_addr != COLLECTION_NOT_MAPPED))

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struct its_ite {
	struct list_head ite_list;
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	struct vgic_irq *irq;
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	struct its_collection *collection;
	u32 lpi;
	u32 event_id;
};

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/**
 * struct vgic_its_abi - ITS abi ops and settings
 * @cte_esz: collection table entry size
 * @dte_esz: device table entry size
 * @ite_esz: interrupt translation table entry size
 * @save tables: save the ITS tables into guest RAM
 * @restore_tables: restore the ITS internal structs from tables
 *  stored in guest RAM
 * @commit: initialize the registers which expose the ABI settings,
 *  especially the entry sizes
 */
struct vgic_its_abi {
	int cte_esz;
	int dte_esz;
	int ite_esz;
	int (*save_tables)(struct vgic_its *its);
	int (*restore_tables)(struct vgic_its *its);
	int (*commit)(struct vgic_its *its);
};

static const struct vgic_its_abi its_table_abi_versions[] = {
	[0] = {.cte_esz = 8, .dte_esz = 8, .ite_esz = 8,
	 .save_tables = vgic_its_save_tables_v0,
	 .restore_tables = vgic_its_restore_tables_v0,
	 .commit = vgic_its_commit_v0,
	},
};

#define NR_ITS_ABIS	ARRAY_SIZE(its_table_abi_versions)

inline const struct vgic_its_abi *vgic_its_get_abi(struct vgic_its *its)
{
	return &its_table_abi_versions[its->abi_rev];
}

int vgic_its_set_abi(struct vgic_its *its, int rev)
{
	const struct vgic_its_abi *abi;

	its->abi_rev = rev;
	abi = vgic_its_get_abi(its);
	return abi->commit(its);
}

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/*
 * Find and returns a device in the device table for an ITS.
 * Must be called with the its_lock mutex held.
 */
static struct its_device *find_its_device(struct vgic_its *its, u32 device_id)
{
	struct its_device *device;

	list_for_each_entry(device, &its->device_list, dev_list)
		if (device_id == device->device_id)
			return device;

	return NULL;
}

/*
 * Find and returns an interrupt translation table entry (ITTE) for a given
 * Device ID/Event ID pair on an ITS.
 * Must be called with the its_lock mutex held.
 */
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static struct its_ite *find_ite(struct vgic_its *its, u32 device_id,
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				  u32 event_id)
{
	struct its_device *device;
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	struct its_ite *ite;
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	device = find_its_device(its, device_id);
	if (device == NULL)
		return NULL;

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	list_for_each_entry(ite, &device->itt_head, ite_list)
		if (ite->event_id == event_id)
			return ite;
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	return NULL;
}

/* To be used as an iterator this macro misses the enclosing parentheses */
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#define for_each_lpi_its(dev, ite, its) \
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	list_for_each_entry(dev, &(its)->device_list, dev_list) \
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		list_for_each_entry(ite, &(dev)->itt_head, ite_list)
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/*
 * We only implement 48 bits of PA at the moment, although the ITS
 * supports more. Let's be restrictive here.
 */
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#define BASER_ADDRESS(x)	((x) & GENMASK_ULL(47, 16))
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#define CBASER_ADDRESS(x)	((x) & GENMASK_ULL(47, 12))
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#define PENDBASER_ADDRESS(x)	((x) & GENMASK_ULL(47, 16))
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#define PROPBASER_ADDRESS(x)	((x) & GENMASK_ULL(47, 12))

#define GIC_LPI_OFFSET 8192

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#define VITS_TYPER_IDBITS 16

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/*
 * Finds and returns a collection in the ITS collection table.
 * Must be called with the its_lock mutex held.
 */
static struct its_collection *find_collection(struct vgic_its *its, int coll_id)
{
	struct its_collection *collection;

	list_for_each_entry(collection, &its->collection_list, coll_list) {
		if (coll_id == collection->collection_id)
			return collection;
	}

	return NULL;
}

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#define LPI_PROP_ENABLE_BIT(p)	((p) & LPI_PROP_ENABLED)
#define LPI_PROP_PRIORITY(p)	((p) & 0xfc)

/*
 * Reads the configuration data for a given LPI from guest memory and
 * updates the fields in struct vgic_irq.
 * If filter_vcpu is not NULL, applies only if the IRQ is targeting this
 * VCPU. Unconditionally applies if filter_vcpu is NULL.
 */
static int update_lpi_config(struct kvm *kvm, struct vgic_irq *irq,
			     struct kvm_vcpu *filter_vcpu)
{
	u64 propbase = PROPBASER_ADDRESS(kvm->arch.vgic.propbaser);
	u8 prop;
	int ret;

	ret = kvm_read_guest(kvm, propbase + irq->intid - GIC_LPI_OFFSET,
			     &prop, 1);

	if (ret)
		return ret;

	spin_lock(&irq->irq_lock);

	if (!filter_vcpu || filter_vcpu == irq->target_vcpu) {
		irq->priority = LPI_PROP_PRIORITY(prop);
		irq->enabled = LPI_PROP_ENABLE_BIT(prop);

		vgic_queue_irq_unlock(kvm, irq);
	} else {
		spin_unlock(&irq->irq_lock);
	}

	return 0;
}
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/*
 * Create a snapshot of the current LPI list, so that we can enumerate all
 * LPIs without holding any lock.
 * Returns the array length and puts the kmalloc'ed array into intid_ptr.
 */
static int vgic_copy_lpi_list(struct kvm *kvm, u32 **intid_ptr)
{
	struct vgic_dist *dist = &kvm->arch.vgic;
	struct vgic_irq *irq;
	u32 *intids;
	int irq_count = dist->lpi_list_count, i = 0;

	/*
	 * We use the current value of the list length, which may change
	 * after the kmalloc. We don't care, because the guest shouldn't
	 * change anything while the command handling is still running,
	 * and in the worst case we would miss a new IRQ, which one wouldn't
	 * expect to be covered by this command anyway.
	 */
	intids = kmalloc_array(irq_count, sizeof(intids[0]), GFP_KERNEL);
	if (!intids)
		return -ENOMEM;

	spin_lock(&dist->lpi_list_lock);
	list_for_each_entry(irq, &dist->lpi_list_head, lpi_list) {
		/* We don't need to "get" the IRQ, as we hold the list lock. */
		intids[i] = irq->intid;
		if (++i == irq_count)
			break;
	}
	spin_unlock(&dist->lpi_list_lock);

	*intid_ptr = intids;
	return irq_count;
}

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/*
 * Promotes the ITS view of affinity of an ITTE (which redistributor this LPI
 * is targeting) to the VGIC's view, which deals with target VCPUs.
 * Needs to be called whenever either the collection for a LPIs has
 * changed or the collection itself got retargeted.
 */
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static void update_affinity_ite(struct kvm *kvm, struct its_ite *ite)
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{
	struct kvm_vcpu *vcpu;

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	if (!its_is_collection_mapped(ite->collection))
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		return;

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	vcpu = kvm_get_vcpu(kvm, ite->collection->target_addr);
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	spin_lock(&ite->irq->irq_lock);
	ite->irq->target_vcpu = vcpu;
	spin_unlock(&ite->irq->irq_lock);
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}

/*
 * Updates the target VCPU for every LPI targeting this collection.
 * Must be called with the its_lock mutex held.
 */
static void update_affinity_collection(struct kvm *kvm, struct vgic_its *its,
				       struct its_collection *coll)
{
	struct its_device *device;
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	struct its_ite *ite;
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	for_each_lpi_its(device, ite, its) {
		if (!ite->collection || coll != ite->collection)
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			continue;

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		update_affinity_ite(kvm, ite);
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	}
}

static u32 max_lpis_propbaser(u64 propbaser)
{
	int nr_idbits = (propbaser & 0x1f) + 1;

	return 1U << min(nr_idbits, INTERRUPT_ID_BITS_ITS);
}

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/*
 * Scan the whole LPI pending table and sync the pending bit in there
 * with our own data structures. This relies on the LPI being
 * mapped before.
 */
static int its_sync_lpi_pending_table(struct kvm_vcpu *vcpu)
{
	gpa_t pendbase = PENDBASER_ADDRESS(vcpu->arch.vgic_cpu.pendbaser);
	struct vgic_irq *irq;
	int last_byte_offset = -1;
	int ret = 0;
	u32 *intids;
	int nr_irqs, i;

	nr_irqs = vgic_copy_lpi_list(vcpu->kvm, &intids);
	if (nr_irqs < 0)
		return nr_irqs;

	for (i = 0; i < nr_irqs; i++) {
		int byte_offset, bit_nr;
		u8 pendmask;

		byte_offset = intids[i] / BITS_PER_BYTE;
		bit_nr = intids[i] % BITS_PER_BYTE;

		/*
		 * For contiguously allocated LPIs chances are we just read
		 * this very same byte in the last iteration. Reuse that.
		 */
		if (byte_offset != last_byte_offset) {
			ret = kvm_read_guest(vcpu->kvm, pendbase + byte_offset,
					     &pendmask, 1);
			if (ret) {
				kfree(intids);
				return ret;
			}
			last_byte_offset = byte_offset;
		}

		irq = vgic_get_irq(vcpu->kvm, NULL, intids[i]);
		spin_lock(&irq->irq_lock);
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		irq->pending_latch = pendmask & (1U << bit_nr);
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		vgic_queue_irq_unlock(vcpu->kvm, irq);
		vgic_put_irq(vcpu->kvm, irq);
	}

	kfree(intids);

	return ret;
}
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static unsigned long vgic_mmio_read_its_typer(struct kvm *kvm,
					      struct vgic_its *its,
					      gpa_t addr, unsigned int len)
{
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	const struct vgic_its_abi *abi = vgic_its_get_abi(its);
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	u64 reg = GITS_TYPER_PLPIS;

	/*
	 * We use linear CPU numbers for redistributor addressing,
	 * so GITS_TYPER.PTA is 0.
	 * Also we force all PROPBASER registers to be the same, so
	 * CommonLPIAff is 0 as well.
	 * To avoid memory waste in the guest, we keep the number of IDBits and
	 * DevBits low - as least for the time being.
	 */
	reg |= 0x0f << GITS_TYPER_DEVBITS_SHIFT;
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	reg |= GIC_ENCODE_SZ(VITS_TYPER_IDBITS, 5) << GITS_TYPER_IDBITS_SHIFT;
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	reg |= GIC_ENCODE_SZ(abi->ite_esz, 4) << GITS_TYPER_ITT_ENTRY_SIZE_SHIFT;
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	return extract_bytes(reg, addr & 7, len);
}

static unsigned long vgic_mmio_read_its_iidr(struct kvm *kvm,
					     struct vgic_its *its,
					     gpa_t addr, unsigned int len)
{
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	u32 val;

	val = (its->abi_rev << GITS_IIDR_REV_SHIFT) & GITS_IIDR_REV_MASK;
	val |= (PRODUCT_ID_KVM << GITS_IIDR_PRODUCTID_SHIFT) | IMPLEMENTER_ARM;
	return val;
}

static int vgic_mmio_uaccess_write_its_iidr(struct kvm *kvm,
					    struct vgic_its *its,
					    gpa_t addr, unsigned int len,
					    unsigned long val)
{
	u32 rev = GITS_IIDR_REV(val);

	if (rev >= NR_ITS_ABIS)
		return -EINVAL;
	return vgic_its_set_abi(its, rev);
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}

static unsigned long vgic_mmio_read_its_idregs(struct kvm *kvm,
					       struct vgic_its *its,
					       gpa_t addr, unsigned int len)
{
	switch (addr & 0xffff) {
	case GITS_PIDR0:
		return 0x92;	/* part number, bits[7:0] */
	case GITS_PIDR1:
		return 0xb4;	/* part number, bits[11:8] */
	case GITS_PIDR2:
		return GIC_PIDR2_ARCH_GICv3 | 0x0b;
	case GITS_PIDR4:
		return 0x40;	/* This is a 64K software visible page */
	/* The following are the ID registers for (any) GIC. */
	case GITS_CIDR0:
		return 0x0d;
	case GITS_CIDR1:
		return 0xf0;
	case GITS_CIDR2:
		return 0x05;
	case GITS_CIDR3:
		return 0xb1;
	}

	return 0;
}

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/*
 * Find the target VCPU and the LPI number for a given devid/eventid pair
 * and make this IRQ pending, possibly injecting it.
 * Must be called with the its_lock mutex held.
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 * Returns 0 on success, a positive error value for any ITS mapping
 * related errors and negative error values for generic errors.
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 */
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static int vgic_its_trigger_msi(struct kvm *kvm, struct vgic_its *its,
				u32 devid, u32 eventid)
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{
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	struct kvm_vcpu *vcpu;
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	struct its_ite *ite;
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	if (!its->enabled)
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		return -EBUSY;
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	ite = find_ite(its, devid, eventid);
	if (!ite || !its_is_collection_mapped(ite->collection))
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		return E_ITS_INT_UNMAPPED_INTERRUPT;

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	vcpu = kvm_get_vcpu(kvm, ite->collection->target_addr);
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	if (!vcpu)
		return E_ITS_INT_UNMAPPED_INTERRUPT;

	if (!vcpu->arch.vgic_cpu.lpis_enabled)
		return -EBUSY;

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	spin_lock(&ite->irq->irq_lock);
	ite->irq->pending_latch = true;
	vgic_queue_irq_unlock(kvm, ite->irq);
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	return 0;
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}

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static struct vgic_io_device *vgic_get_its_iodev(struct kvm_io_device *dev)
{
	struct vgic_io_device *iodev;

	if (dev->ops != &kvm_io_gic_ops)
		return NULL;

	iodev = container_of(dev, struct vgic_io_device, dev);

	if (iodev->iodev_type != IODEV_ITS)
		return NULL;

	return iodev;
}

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/*
 * Queries the KVM IO bus framework to get the ITS pointer from the given
 * doorbell address.
 * We then call vgic_its_trigger_msi() with the decoded data.
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 * According to the KVM_SIGNAL_MSI API description returns 1 on success.
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 */
int vgic_its_inject_msi(struct kvm *kvm, struct kvm_msi *msi)
{
	u64 address;
	struct kvm_io_device *kvm_io_dev;
	struct vgic_io_device *iodev;
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	int ret;
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	if (!vgic_has_its(kvm))
		return -ENODEV;

	if (!(msi->flags & KVM_MSI_VALID_DEVID))
		return -EINVAL;

	address = (u64)msi->address_hi << 32 | msi->address_lo;

	kvm_io_dev = kvm_io_bus_get_dev(kvm, KVM_MMIO_BUS, address);
	if (!kvm_io_dev)
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		return -EINVAL;
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	iodev = vgic_get_its_iodev(kvm_io_dev);
	if (!iodev)
		return -EINVAL;
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	mutex_lock(&iodev->its->its_lock);
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	ret = vgic_its_trigger_msi(kvm, iodev->its, msi->devid, msi->data);
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	mutex_unlock(&iodev->its->its_lock);

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	if (ret < 0)
		return ret;

	/*
	 * KVM_SIGNAL_MSI demands a return value > 0 for success and 0
	 * if the guest has blocked the MSI. So we map any LPI mapping
	 * related error to that.
	 */
	if (ret)
		return 0;
	else
		return 1;
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}

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/* Requires the its_lock to be held. */
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static void its_free_ite(struct kvm *kvm, struct its_ite *ite)
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{
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	list_del(&ite->ite_list);
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	/* This put matches the get in vgic_add_lpi. */
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	if (ite->irq)
		vgic_put_irq(kvm, ite->irq);
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	kfree(ite);
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}

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static u64 its_cmd_mask_field(u64 *its_cmd, int word, int shift, int size)
{
	return (le64_to_cpu(its_cmd[word]) >> shift) & (BIT_ULL(size) - 1);
}

#define its_cmd_get_command(cmd)	its_cmd_mask_field(cmd, 0,  0,  8)
#define its_cmd_get_deviceid(cmd)	its_cmd_mask_field(cmd, 0, 32, 32)
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#define its_cmd_get_size(cmd)		(its_cmd_mask_field(cmd, 1,  0,  5) + 1)
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#define its_cmd_get_id(cmd)		its_cmd_mask_field(cmd, 1,  0, 32)
#define its_cmd_get_physical_id(cmd)	its_cmd_mask_field(cmd, 1, 32, 32)
#define its_cmd_get_collection(cmd)	its_cmd_mask_field(cmd, 2,  0, 16)
#define its_cmd_get_target_addr(cmd)	its_cmd_mask_field(cmd, 2, 16, 32)
#define its_cmd_get_validbit(cmd)	its_cmd_mask_field(cmd, 2, 63,  1)

/*
 * The DISCARD command frees an Interrupt Translation Table Entry (ITTE).
 * Must be called with the its_lock mutex held.
 */
static int vgic_its_cmd_handle_discard(struct kvm *kvm, struct vgic_its *its,
				       u64 *its_cmd)
{
	u32 device_id = its_cmd_get_deviceid(its_cmd);
	u32 event_id = its_cmd_get_id(its_cmd);
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	struct its_ite *ite;
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	ite = find_ite(its, device_id, event_id);
	if (ite && ite->collection) {
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		/*
		 * Though the spec talks about removing the pending state, we
		 * don't bother here since we clear the ITTE anyway and the
		 * pending state is a property of the ITTE struct.
		 */
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		its_free_ite(kvm, ite);
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		return 0;
	}

	return E_ITS_DISCARD_UNMAPPED_INTERRUPT;
}

/*
 * The MOVI command moves an ITTE to a different collection.
 * Must be called with the its_lock mutex held.
 */
static int vgic_its_cmd_handle_movi(struct kvm *kvm, struct vgic_its *its,
				    u64 *its_cmd)
{
	u32 device_id = its_cmd_get_deviceid(its_cmd);
	u32 event_id = its_cmd_get_id(its_cmd);
	u32 coll_id = its_cmd_get_collection(its_cmd);
	struct kvm_vcpu *vcpu;
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	struct its_ite *ite;
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	struct its_collection *collection;

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	ite = find_ite(its, device_id, event_id);
	if (!ite)
650 651
		return E_ITS_MOVI_UNMAPPED_INTERRUPT;

652
	if (!its_is_collection_mapped(ite->collection))
653 654 655 656 657 658
		return E_ITS_MOVI_UNMAPPED_COLLECTION;

	collection = find_collection(its, coll_id);
	if (!its_is_collection_mapped(collection))
		return E_ITS_MOVI_UNMAPPED_COLLECTION;

659
	ite->collection = collection;
660 661
	vcpu = kvm_get_vcpu(kvm, collection->target_addr);

662 663 664
	spin_lock(&ite->irq->irq_lock);
	ite->irq->target_vcpu = vcpu;
	spin_unlock(&ite->irq->irq_lock);
665 666 667 668

	return 0;
}

669 670 671 672 673 674 675 676 677 678 679 680 681
/*
 * Check whether an ID can be stored into the corresponding guest table.
 * For a direct table this is pretty easy, but gets a bit nasty for
 * indirect tables. We check whether the resulting guest physical address
 * is actually valid (covered by a memslot and guest accessbible).
 * For this we have to read the respective first level entry.
 */
static bool vgic_its_check_id(struct vgic_its *its, u64 baser, int id)
{
	int l1_tbl_size = GITS_BASER_NR_PAGES(baser) * SZ_64K;
	int index;
	u64 indirect_ptr;
	gfn_t gfn;
682
	int esz = GITS_BASER_ENTRY_SIZE(baser);
683 684 685 686

	if (!(baser & GITS_BASER_INDIRECT)) {
		phys_addr_t addr;

687
		if (id >= (l1_tbl_size / esz))
688 689
			return false;

690
		addr = BASER_ADDRESS(baser) + id * esz;
691 692 693 694 695 696
		gfn = addr >> PAGE_SHIFT;

		return kvm_is_visible_gfn(its->dev->kvm, gfn);
	}

	/* calculate and check the index into the 1st level */
697
	index = id / (SZ_64K / esz);
698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720
	if (index >= (l1_tbl_size / sizeof(u64)))
		return false;

	/* Each 1st level entry is represented by a 64-bit value. */
	if (kvm_read_guest(its->dev->kvm,
			   BASER_ADDRESS(baser) + index * sizeof(indirect_ptr),
			   &indirect_ptr, sizeof(indirect_ptr)))
		return false;

	indirect_ptr = le64_to_cpu(indirect_ptr);

	/* check the valid bit of the first level entry */
	if (!(indirect_ptr & BIT_ULL(63)))
		return false;

	/*
	 * Mask the guest physical address and calculate the frame number.
	 * Any address beyond our supported 48 bits of PA will be caught
	 * by the actual check in the final step.
	 */
	indirect_ptr &= GENMASK_ULL(51, 16);

	/* Find the address of the actual entry */
721 722
	index = id % (SZ_64K / esz);
	indirect_ptr += index * esz;
723 724 725 726 727
	gfn = indirect_ptr >> PAGE_SHIFT;

	return kvm_is_visible_gfn(its->dev->kvm, gfn);
}

728 729
static int vgic_its_alloc_collection(struct vgic_its *its,
				     struct its_collection **colp,
730 731
				     u32 coll_id)
{
732 733
	struct its_collection *collection;

734 735 736
	if (!vgic_its_check_id(its, its->baser_coll_table, coll_id))
		return E_ITS_MAPC_COLLECTION_OOR;

737 738
	collection = kzalloc(sizeof(*collection), GFP_KERNEL);

739 740 741 742
	collection->collection_id = coll_id;
	collection->target_addr = COLLECTION_NOT_MAPPED;

	list_add_tail(&collection->coll_list, &its->collection_list);
743 744 745 746 747 748 749 750 751
	*colp = collection;

	return 0;
}

static void vgic_its_free_collection(struct vgic_its *its, u32 coll_id)
{
	struct its_collection *collection;
	struct its_device *device;
752
	struct its_ite *ite;
753 754 755 756 757 758 759 760 761 762

	/*
	 * Clearing the mapping for that collection ID removes the
	 * entry from the list. If there wasn't any before, we can
	 * go home early.
	 */
	collection = find_collection(its, coll_id);
	if (!collection)
		return;

763 764 765 766
	for_each_lpi_its(device, ite, its)
		if (ite->collection &&
		    ite->collection->collection_id == coll_id)
			ite->collection = NULL;
767 768 769

	list_del(&collection->coll_list);
	kfree(collection);
770 771 772 773 774 775 776
}

/*
 * The MAPTI and MAPI commands map LPIs to ITTEs.
 * Must be called with its_lock mutex held.
 */
static int vgic_its_cmd_handle_mapi(struct kvm *kvm, struct vgic_its *its,
777
				    u64 *its_cmd)
778 779 780 781
{
	u32 device_id = its_cmd_get_deviceid(its_cmd);
	u32 event_id = its_cmd_get_id(its_cmd);
	u32 coll_id = its_cmd_get_collection(its_cmd);
782
	struct its_ite *ite;
783 784 785
	struct its_device *device;
	struct its_collection *collection, *new_coll = NULL;
	int lpi_nr;
786
	struct vgic_irq *irq;
787 788 789 790 791

	device = find_its_device(its, device_id);
	if (!device)
		return E_ITS_MAPTI_UNMAPPED_DEVICE;

792 793 794
	if (event_id >= BIT_ULL(device->num_eventid_bits))
		return E_ITS_MAPTI_ID_OOR;

795
	if (its_cmd_get_command(its_cmd) == GITS_CMD_MAPTI)
796 797 798 799
		lpi_nr = its_cmd_get_physical_id(its_cmd);
	else
		lpi_nr = event_id;
	if (lpi_nr < GIC_LPI_OFFSET ||
800 801 802
	    lpi_nr >= max_lpis_propbaser(kvm->arch.vgic.propbaser))
		return E_ITS_MAPTI_PHYSICALID_OOR;

803
	/* If there is an existing mapping, behavior is UNPREDICTABLE. */
804
	if (find_ite(its, device_id, event_id))
805 806
		return 0;

807 808 809 810 811 812
	collection = find_collection(its, coll_id);
	if (!collection) {
		int ret = vgic_its_alloc_collection(its, &collection, coll_id);
		if (ret)
			return ret;
		new_coll = collection;
813 814
	}

815 816
	ite = kzalloc(sizeof(struct its_ite), GFP_KERNEL);
	if (!ite) {
817 818 819
		if (new_coll)
			vgic_its_free_collection(its, coll_id);
		return -ENOMEM;
820 821
	}

822 823
	ite->event_id	= event_id;
	list_add_tail(&ite->ite_list, &device->itt_head);
824

825 826
	ite->collection = collection;
	ite->lpi = lpi_nr;
827 828 829 830 831

	irq = vgic_add_lpi(kvm, lpi_nr);
	if (IS_ERR(irq)) {
		if (new_coll)
			vgic_its_free_collection(its, coll_id);
832
		its_free_ite(kvm, ite);
833 834
		return PTR_ERR(irq);
	}
835
	ite->irq = irq;
836

837
	update_affinity_ite(kvm, ite);
838 839 840 841 842 843

	/*
	 * We "cache" the configuration table entries in out struct vgic_irq's.
	 * However we only have those structs for mapped IRQs, so we read in
	 * the respective config data from memory here upon mapping the LPI.
	 */
844
	update_lpi_config(kvm, ite->irq, NULL);
845 846 847 848 849 850 851

	return 0;
}

/* Requires the its_lock to be held. */
static void vgic_its_unmap_device(struct kvm *kvm, struct its_device *device)
{
852
	struct its_ite *ite, *temp;
853 854 855 856 857 858

	/*
	 * The spec says that unmapping a device with still valid
	 * ITTEs associated is UNPREDICTABLE. We remove all ITTEs,
	 * since we cannot leave the memory unreferenced.
	 */
859 860
	list_for_each_entry_safe(ite, temp, &device->itt_head, ite_list)
		its_free_ite(kvm, ite);
861 862 863 864 865 866 867 868 869 870 871 872 873 874

	list_del(&device->dev_list);
	kfree(device);
}

/*
 * MAPD maps or unmaps a device ID to Interrupt Translation Tables (ITTs).
 * Must be called with the its_lock mutex held.
 */
static int vgic_its_cmd_handle_mapd(struct kvm *kvm, struct vgic_its *its,
				    u64 *its_cmd)
{
	u32 device_id = its_cmd_get_deviceid(its_cmd);
	bool valid = its_cmd_get_validbit(its_cmd);
875
	u8 num_eventid_bits = its_cmd_get_size(its_cmd);
876 877
	struct its_device *device;

878
	if (!vgic_its_check_id(its, its->baser_device_table, device_id))
879 880
		return E_ITS_MAPD_DEVICE_OOR;

881 882 883
	if (valid && num_eventid_bits > VITS_TYPER_IDBITS)
		return E_ITS_MAPD_ITTSIZE_OOR;

884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905
	device = find_its_device(its, device_id);

	/*
	 * The spec says that calling MAPD on an already mapped device
	 * invalidates all cached data for this device. We implement this
	 * by removing the mapping and re-establishing it.
	 */
	if (device)
		vgic_its_unmap_device(kvm, device);

	/*
	 * The spec does not say whether unmapping a not-mapped device
	 * is an error, so we are done in any case.
	 */
	if (!valid)
		return 0;

	device = kzalloc(sizeof(struct its_device), GFP_KERNEL);
	if (!device)
		return -ENOMEM;

	device->device_id = device_id;
906 907
	device->num_eventid_bits = num_eventid_bits;

908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934
	INIT_LIST_HEAD(&device->itt_head);

	list_add_tail(&device->dev_list, &its->device_list);

	return 0;
}

/*
 * The MAPC command maps collection IDs to redistributors.
 * Must be called with the its_lock mutex held.
 */
static int vgic_its_cmd_handle_mapc(struct kvm *kvm, struct vgic_its *its,
				    u64 *its_cmd)
{
	u16 coll_id;
	u32 target_addr;
	struct its_collection *collection;
	bool valid;

	valid = its_cmd_get_validbit(its_cmd);
	coll_id = its_cmd_get_collection(its_cmd);
	target_addr = its_cmd_get_target_addr(its_cmd);

	if (target_addr >= atomic_read(&kvm->online_vcpus))
		return E_ITS_MAPC_PROCNUM_OOR;

	if (!valid) {
935
		vgic_its_free_collection(its, coll_id);
936
	} else {
937 938
		collection = find_collection(its, coll_id);

939
		if (!collection) {
940
			int ret;
941

942 943 944 945
			ret = vgic_its_alloc_collection(its, &collection,
							coll_id);
			if (ret)
				return ret;
946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964
			collection->target_addr = target_addr;
		} else {
			collection->target_addr = target_addr;
			update_affinity_collection(kvm, its, collection);
		}
	}

	return 0;
}

/*
 * The CLEAR command removes the pending state for a particular LPI.
 * Must be called with the its_lock mutex held.
 */
static int vgic_its_cmd_handle_clear(struct kvm *kvm, struct vgic_its *its,
				     u64 *its_cmd)
{
	u32 device_id = its_cmd_get_deviceid(its_cmd);
	u32 event_id = its_cmd_get_id(its_cmd);
965
	struct its_ite *ite;
966 967


968 969
	ite = find_ite(its, device_id, event_id);
	if (!ite)
970 971
		return E_ITS_CLEAR_UNMAPPED_INTERRUPT;

972
	ite->irq->pending_latch = false;
973 974 975 976 977 978 979 980 981 982 983 984 985

	return 0;
}

/*
 * The INV command syncs the configuration bits from the memory table.
 * Must be called with the its_lock mutex held.
 */
static int vgic_its_cmd_handle_inv(struct kvm *kvm, struct vgic_its *its,
				   u64 *its_cmd)
{
	u32 device_id = its_cmd_get_deviceid(its_cmd);
	u32 event_id = its_cmd_get_id(its_cmd);
986
	struct its_ite *ite;
987 988


989 990
	ite = find_ite(its, device_id, event_id);
	if (!ite)
991 992
		return E_ITS_INV_UNMAPPED_INTERRUPT;

993
	return update_lpi_config(kvm, ite->irq, NULL);
994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079
}

/*
 * The INVALL command requests flushing of all IRQ data in this collection.
 * Find the VCPU mapped to that collection, then iterate over the VM's list
 * of mapped LPIs and update the configuration for each IRQ which targets
 * the specified vcpu. The configuration will be read from the in-memory
 * configuration table.
 * Must be called with the its_lock mutex held.
 */
static int vgic_its_cmd_handle_invall(struct kvm *kvm, struct vgic_its *its,
				      u64 *its_cmd)
{
	u32 coll_id = its_cmd_get_collection(its_cmd);
	struct its_collection *collection;
	struct kvm_vcpu *vcpu;
	struct vgic_irq *irq;
	u32 *intids;
	int irq_count, i;

	collection = find_collection(its, coll_id);
	if (!its_is_collection_mapped(collection))
		return E_ITS_INVALL_UNMAPPED_COLLECTION;

	vcpu = kvm_get_vcpu(kvm, collection->target_addr);

	irq_count = vgic_copy_lpi_list(kvm, &intids);
	if (irq_count < 0)
		return irq_count;

	for (i = 0; i < irq_count; i++) {
		irq = vgic_get_irq(kvm, NULL, intids[i]);
		if (!irq)
			continue;
		update_lpi_config(kvm, irq, vcpu);
		vgic_put_irq(kvm, irq);
	}

	kfree(intids);

	return 0;
}

/*
 * The MOVALL command moves the pending state of all IRQs targeting one
 * redistributor to another. We don't hold the pending state in the VCPUs,
 * but in the IRQs instead, so there is really not much to do for us here.
 * However the spec says that no IRQ must target the old redistributor
 * afterwards, so we make sure that no LPI is using the associated target_vcpu.
 * This command affects all LPIs in the system that target that redistributor.
 */
static int vgic_its_cmd_handle_movall(struct kvm *kvm, struct vgic_its *its,
				      u64 *its_cmd)
{
	struct vgic_dist *dist = &kvm->arch.vgic;
	u32 target1_addr = its_cmd_get_target_addr(its_cmd);
	u32 target2_addr = its_cmd_mask_field(its_cmd, 3, 16, 32);
	struct kvm_vcpu *vcpu1, *vcpu2;
	struct vgic_irq *irq;

	if (target1_addr >= atomic_read(&kvm->online_vcpus) ||
	    target2_addr >= atomic_read(&kvm->online_vcpus))
		return E_ITS_MOVALL_PROCNUM_OOR;

	if (target1_addr == target2_addr)
		return 0;

	vcpu1 = kvm_get_vcpu(kvm, target1_addr);
	vcpu2 = kvm_get_vcpu(kvm, target2_addr);

	spin_lock(&dist->lpi_list_lock);

	list_for_each_entry(irq, &dist->lpi_list_head, lpi_list) {
		spin_lock(&irq->irq_lock);

		if (irq->target_vcpu == vcpu1)
			irq->target_vcpu = vcpu2;

		spin_unlock(&irq->irq_lock);
	}

	spin_unlock(&dist->lpi_list_lock);

	return 0;
}

1080 1081 1082 1083 1084 1085 1086 1087 1088 1089
/*
 * The INT command injects the LPI associated with that DevID/EvID pair.
 * Must be called with the its_lock mutex held.
 */
static int vgic_its_cmd_handle_int(struct kvm *kvm, struct vgic_its *its,
				   u64 *its_cmd)
{
	u32 msi_data = its_cmd_get_id(its_cmd);
	u64 msi_devid = its_cmd_get_deviceid(its_cmd);

1090
	return vgic_its_trigger_msi(kvm, its, msi_devid, msi_data);
1091 1092
}

1093 1094 1095 1096
/*
 * This function is called with the its_cmd lock held, but the ITS data
 * structure lock dropped.
 */
1097 1098 1099
static int vgic_its_handle_command(struct kvm *kvm, struct vgic_its *its,
				   u64 *its_cmd)
{
1100 1101 1102
	int ret = -ENODEV;

	mutex_lock(&its->its_lock);
1103
	switch (its_cmd_get_command(its_cmd)) {
1104 1105 1106 1107 1108 1109 1110
	case GITS_CMD_MAPD:
		ret = vgic_its_cmd_handle_mapd(kvm, its, its_cmd);
		break;
	case GITS_CMD_MAPC:
		ret = vgic_its_cmd_handle_mapc(kvm, its, its_cmd);
		break;
	case GITS_CMD_MAPI:
1111
		ret = vgic_its_cmd_handle_mapi(kvm, its, its_cmd);
1112 1113
		break;
	case GITS_CMD_MAPTI:
1114
		ret = vgic_its_cmd_handle_mapi(kvm, its, its_cmd);
1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127
		break;
	case GITS_CMD_MOVI:
		ret = vgic_its_cmd_handle_movi(kvm, its, its_cmd);
		break;
	case GITS_CMD_DISCARD:
		ret = vgic_its_cmd_handle_discard(kvm, its, its_cmd);
		break;
	case GITS_CMD_CLEAR:
		ret = vgic_its_cmd_handle_clear(kvm, its, its_cmd);
		break;
	case GITS_CMD_MOVALL:
		ret = vgic_its_cmd_handle_movall(kvm, its, its_cmd);
		break;
1128 1129 1130
	case GITS_CMD_INT:
		ret = vgic_its_cmd_handle_int(kvm, its, its_cmd);
		break;
1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144
	case GITS_CMD_INV:
		ret = vgic_its_cmd_handle_inv(kvm, its, its_cmd);
		break;
	case GITS_CMD_INVALL:
		ret = vgic_its_cmd_handle_invall(kvm, its, its_cmd);
		break;
	case GITS_CMD_SYNC:
		/* we ignore this command: we are in sync all of the time */
		ret = 0;
		break;
	}
	mutex_unlock(&its->its_lock);

	return ret;
1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219
}

static u64 vgic_sanitise_its_baser(u64 reg)
{
	reg = vgic_sanitise_field(reg, GITS_BASER_SHAREABILITY_MASK,
				  GITS_BASER_SHAREABILITY_SHIFT,
				  vgic_sanitise_shareability);
	reg = vgic_sanitise_field(reg, GITS_BASER_INNER_CACHEABILITY_MASK,
				  GITS_BASER_INNER_CACHEABILITY_SHIFT,
				  vgic_sanitise_inner_cacheability);
	reg = vgic_sanitise_field(reg, GITS_BASER_OUTER_CACHEABILITY_MASK,
				  GITS_BASER_OUTER_CACHEABILITY_SHIFT,
				  vgic_sanitise_outer_cacheability);

	/* Bits 15:12 contain bits 51:48 of the PA, which we don't support. */
	reg &= ~GENMASK_ULL(15, 12);

	/* We support only one (ITS) page size: 64K */
	reg = (reg & ~GITS_BASER_PAGE_SIZE_MASK) | GITS_BASER_PAGE_SIZE_64K;

	return reg;
}

static u64 vgic_sanitise_its_cbaser(u64 reg)
{
	reg = vgic_sanitise_field(reg, GITS_CBASER_SHAREABILITY_MASK,
				  GITS_CBASER_SHAREABILITY_SHIFT,
				  vgic_sanitise_shareability);
	reg = vgic_sanitise_field(reg, GITS_CBASER_INNER_CACHEABILITY_MASK,
				  GITS_CBASER_INNER_CACHEABILITY_SHIFT,
				  vgic_sanitise_inner_cacheability);
	reg = vgic_sanitise_field(reg, GITS_CBASER_OUTER_CACHEABILITY_MASK,
				  GITS_CBASER_OUTER_CACHEABILITY_SHIFT,
				  vgic_sanitise_outer_cacheability);

	/*
	 * Sanitise the physical address to be 64k aligned.
	 * Also limit the physical addresses to 48 bits.
	 */
	reg &= ~(GENMASK_ULL(51, 48) | GENMASK_ULL(15, 12));

	return reg;
}

static unsigned long vgic_mmio_read_its_cbaser(struct kvm *kvm,
					       struct vgic_its *its,
					       gpa_t addr, unsigned int len)
{
	return extract_bytes(its->cbaser, addr & 7, len);
}

static void vgic_mmio_write_its_cbaser(struct kvm *kvm, struct vgic_its *its,
				       gpa_t addr, unsigned int len,
				       unsigned long val)
{
	/* When GITS_CTLR.Enable is 1, this register is RO. */
	if (its->enabled)
		return;

	mutex_lock(&its->cmd_lock);
	its->cbaser = update_64bit_reg(its->cbaser, addr & 7, len, val);
	its->cbaser = vgic_sanitise_its_cbaser(its->cbaser);
	its->creadr = 0;
	/*
	 * CWRITER is architecturally UNKNOWN on reset, but we need to reset
	 * it to CREADR to make sure we start with an empty command buffer.
	 */
	its->cwriter = its->creadr;
	mutex_unlock(&its->cmd_lock);
}

#define ITS_CMD_BUFFER_SIZE(baser)	((((baser) & 0xff) + 1) << 12)
#define ITS_CMD_SIZE			32
#define ITS_CMD_OFFSET(reg)		((reg) & GENMASK(19, 5))

1220 1221
/* Must be called with the cmd_lock held. */
static void vgic_its_process_commands(struct kvm *kvm, struct vgic_its *its)
1222 1223 1224 1225
{
	gpa_t cbaser;
	u64 cmd_buf[4];

1226 1227
	/* Commands are only processed when the ITS is enabled. */
	if (!its->enabled)
1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248
		return;

	cbaser = CBASER_ADDRESS(its->cbaser);

	while (its->cwriter != its->creadr) {
		int ret = kvm_read_guest(kvm, cbaser + its->creadr,
					 cmd_buf, ITS_CMD_SIZE);
		/*
		 * If kvm_read_guest() fails, this could be due to the guest
		 * programming a bogus value in CBASER or something else going
		 * wrong from which we cannot easily recover.
		 * According to section 6.3.2 in the GICv3 spec we can just
		 * ignore that command then.
		 */
		if (!ret)
			vgic_its_handle_command(kvm, its, cmd_buf);

		its->creadr += ITS_CMD_SIZE;
		if (its->creadr == ITS_CMD_BUFFER_SIZE(its->cbaser))
			its->creadr = 0;
	}
1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 1274 1275 1276
}

/*
 * By writing to CWRITER the guest announces new commands to be processed.
 * To avoid any races in the first place, we take the its_cmd lock, which
 * protects our ring buffer variables, so that there is only one user
 * per ITS handling commands at a given time.
 */
static void vgic_mmio_write_its_cwriter(struct kvm *kvm, struct vgic_its *its,
					gpa_t addr, unsigned int len,
					unsigned long val)
{
	u64 reg;

	if (!its)
		return;

	mutex_lock(&its->cmd_lock);

	reg = update_64bit_reg(its->cwriter, addr & 7, len, val);
	reg = ITS_CMD_OFFSET(reg);
	if (reg >= ITS_CMD_BUFFER_SIZE(its->cbaser)) {
		mutex_unlock(&its->cmd_lock);
		return;
	}
	its->cwriter = reg;

	vgic_its_process_commands(kvm, its);
1277 1278 1279 1280 1281 1282 1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293 1294

	mutex_unlock(&its->cmd_lock);
}

static unsigned long vgic_mmio_read_its_cwriter(struct kvm *kvm,
						struct vgic_its *its,
						gpa_t addr, unsigned int len)
{
	return extract_bytes(its->cwriter, addr & 0x7, len);
}

static unsigned long vgic_mmio_read_its_creadr(struct kvm *kvm,
					       struct vgic_its *its,
					       gpa_t addr, unsigned int len)
{
	return extract_bytes(its->creadr, addr & 0x7, len);
}

1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 1313 1314 1315 1316 1317 1318 1319 1320 1321
static int vgic_mmio_uaccess_write_its_creadr(struct kvm *kvm,
					      struct vgic_its *its,
					      gpa_t addr, unsigned int len,
					      unsigned long val)
{
	u32 cmd_offset;
	int ret = 0;

	mutex_lock(&its->cmd_lock);

	if (its->enabled) {
		ret = -EBUSY;
		goto out;
	}

	cmd_offset = ITS_CMD_OFFSET(val);
	if (cmd_offset >= ITS_CMD_BUFFER_SIZE(its->cbaser)) {
		ret = -EINVAL;
		goto out;
	}

	its->creadr = cmd_offset;
out:
	mutex_unlock(&its->cmd_lock);
	return ret;
}

1322 1323 1324 1325 1326 1327 1328 1329 1330 1331 1332 1333 1334 1335 1336 1337 1338 1339 1340 1341 1342 1343 1344 1345 1346 1347 1348 1349
#define BASER_INDEX(addr) (((addr) / sizeof(u64)) & 0x7)
static unsigned long vgic_mmio_read_its_baser(struct kvm *kvm,
					      struct vgic_its *its,
					      gpa_t addr, unsigned int len)
{
	u64 reg;

	switch (BASER_INDEX(addr)) {
	case 0:
		reg = its->baser_device_table;
		break;
	case 1:
		reg = its->baser_coll_table;
		break;
	default:
		reg = 0;
		break;
	}

	return extract_bytes(reg, addr & 7, len);
}

#define GITS_BASER_RO_MASK	(GENMASK_ULL(52, 48) | GENMASK_ULL(58, 56))
static void vgic_mmio_write_its_baser(struct kvm *kvm,
				      struct vgic_its *its,
				      gpa_t addr, unsigned int len,
				      unsigned long val)
{
1350
	const struct vgic_its_abi *abi = vgic_its_get_abi(its);
1351 1352 1353 1354 1355 1356 1357 1358 1359 1360
	u64 entry_size, device_type;
	u64 reg, *regptr, clearbits = 0;

	/* When GITS_CTLR.Enable is 1, we ignore write accesses. */
	if (its->enabled)
		return;

	switch (BASER_INDEX(addr)) {
	case 0:
		regptr = &its->baser_device_table;
1361
		entry_size = abi->dte_esz;
1362 1363 1364 1365
		device_type = GITS_BASER_TYPE_DEVICE;
		break;
	case 1:
		regptr = &its->baser_coll_table;
1366
		entry_size = abi->cte_esz;
1367 1368 1369 1370 1371 1372 1373 1374 1375 1376 1377 1378 1379 1380 1381 1382 1383 1384
		device_type = GITS_BASER_TYPE_COLLECTION;
		clearbits = GITS_BASER_INDIRECT;
		break;
	default:
		return;
	}

	reg = update_64bit_reg(*regptr, addr & 7, len, val);
	reg &= ~GITS_BASER_RO_MASK;
	reg &= ~clearbits;

	reg |= (entry_size - 1) << GITS_BASER_ENTRY_SIZE_SHIFT;
	reg |= device_type << GITS_BASER_TYPE_SHIFT;
	reg = vgic_sanitise_its_baser(reg);

	*regptr = reg;
}

1385 1386 1387 1388 1389 1390 1391 1392 1393 1394 1395 1396 1397 1398 1399 1400 1401 1402 1403 1404 1405 1406 1407 1408 1409 1410 1411 1412 1413 1414 1415 1416 1417
static unsigned long vgic_mmio_read_its_ctlr(struct kvm *vcpu,
					     struct vgic_its *its,
					     gpa_t addr, unsigned int len)
{
	u32 reg = 0;

	mutex_lock(&its->cmd_lock);
	if (its->creadr == its->cwriter)
		reg |= GITS_CTLR_QUIESCENT;
	if (its->enabled)
		reg |= GITS_CTLR_ENABLE;
	mutex_unlock(&its->cmd_lock);

	return reg;
}

static void vgic_mmio_write_its_ctlr(struct kvm *kvm, struct vgic_its *its,
				     gpa_t addr, unsigned int len,
				     unsigned long val)
{
	mutex_lock(&its->cmd_lock);

	its->enabled = !!(val & GITS_CTLR_ENABLE);

	/*
	 * Try to process any pending commands. This function bails out early
	 * if the ITS is disabled or no commands have been queued.
	 */
	vgic_its_process_commands(kvm, its);

	mutex_unlock(&its->cmd_lock);
}

1418 1419 1420 1421 1422 1423 1424 1425 1426
#define REGISTER_ITS_DESC(off, rd, wr, length, acc)		\
{								\
	.reg_offset = off,					\
	.len = length,						\
	.access_flags = acc,					\
	.its_read = rd,						\
	.its_write = wr,					\
}

1427 1428 1429 1430 1431 1432 1433 1434 1435 1436
#define REGISTER_ITS_DESC_UACCESS(off, rd, wr, uwr, length, acc)\
{								\
	.reg_offset = off,					\
	.len = length,						\
	.access_flags = acc,					\
	.its_read = rd,						\
	.its_write = wr,					\
	.uaccess_its_write = uwr,				\
}

1437 1438 1439 1440 1441 1442 1443 1444
static void its_mmio_write_wi(struct kvm *kvm, struct vgic_its *its,
			      gpa_t addr, unsigned int len, unsigned long val)
{
	/* Ignore */
}

static struct vgic_register_region its_registers[] = {
	REGISTER_ITS_DESC(GITS_CTLR,
1445
		vgic_mmio_read_its_ctlr, vgic_mmio_write_its_ctlr, 4,
1446
		VGIC_ACCESS_32bit),
1447 1448 1449
	REGISTER_ITS_DESC_UACCESS(GITS_IIDR,
		vgic_mmio_read_its_iidr, its_mmio_write_wi,
		vgic_mmio_uaccess_write_its_iidr, 4,
1450 1451
		VGIC_ACCESS_32bit),
	REGISTER_ITS_DESC(GITS_TYPER,
1452
		vgic_mmio_read_its_typer, its_mmio_write_wi, 8,
1453 1454
		VGIC_ACCESS_64bit | VGIC_ACCESS_32bit),
	REGISTER_ITS_DESC(GITS_CBASER,
1455
		vgic_mmio_read_its_cbaser, vgic_mmio_write_its_cbaser, 8,
1456 1457
		VGIC_ACCESS_64bit | VGIC_ACCESS_32bit),
	REGISTER_ITS_DESC(GITS_CWRITER,
1458
		vgic_mmio_read_its_cwriter, vgic_mmio_write_its_cwriter, 8,
1459
		VGIC_ACCESS_64bit | VGIC_ACCESS_32bit),
1460 1461 1462
	REGISTER_ITS_DESC_UACCESS(GITS_CREADR,
		vgic_mmio_read_its_creadr, its_mmio_write_wi,
		vgic_mmio_uaccess_write_its_creadr, 8,
1463 1464
		VGIC_ACCESS_64bit | VGIC_ACCESS_32bit),
	REGISTER_ITS_DESC(GITS_BASER,
1465
		vgic_mmio_read_its_baser, vgic_mmio_write_its_baser, 0x40,
1466 1467
		VGIC_ACCESS_64bit | VGIC_ACCESS_32bit),
	REGISTER_ITS_DESC(GITS_IDREGS_BASE,
1468
		vgic_mmio_read_its_idregs, its_mmio_write_wi, 0x30,
1469 1470 1471
		VGIC_ACCESS_32bit),
};

1472 1473 1474 1475 1476 1477 1478
/* This is called on setting the LPI enable bit in the redistributor. */
void vgic_enable_lpis(struct kvm_vcpu *vcpu)
{
	if (!(vcpu->arch.vgic_cpu.pendbaser & GICR_PENDBASER_PTZ))
		its_sync_lpi_pending_table(vcpu);
}

1479
static int vgic_register_its_iodev(struct kvm *kvm, struct vgic_its *its)
1480 1481 1482 1483
{
	struct vgic_io_device *iodev = &its->iodev;
	int ret;

1484 1485
	if (!its->initialized)
		return -EBUSY;
1486

1487 1488 1489 1490 1491 1492 1493 1494 1495 1496 1497 1498 1499 1500 1501 1502 1503
	if (IS_VGIC_ADDR_UNDEF(its->vgic_its_base))
		return -ENXIO;

	iodev->regions = its_registers;
	iodev->nr_regions = ARRAY_SIZE(its_registers);
	kvm_iodevice_init(&iodev->dev, &kvm_io_gic_ops);

	iodev->base_addr = its->vgic_its_base;
	iodev->iodev_type = IODEV_ITS;
	iodev->its = its;
	mutex_lock(&kvm->slots_lock);
	ret = kvm_io_bus_register_dev(kvm, KVM_MMIO_BUS, iodev->base_addr,
				      KVM_VGIC_V3_ITS_SIZE, &iodev->dev);
	mutex_unlock(&kvm->slots_lock);

	return ret;
}
1504

1505 1506 1507 1508 1509 1510 1511 1512 1513 1514 1515
#define INITIAL_BASER_VALUE						  \
	(GIC_BASER_CACHEABILITY(GITS_BASER, INNER, RaWb)		| \
	 GIC_BASER_CACHEABILITY(GITS_BASER, OUTER, SameAsInner)		| \
	 GIC_BASER_SHAREABILITY(GITS_BASER, InnerShareable)		| \
	 GITS_BASER_PAGE_SIZE_64K)

#define INITIAL_PROPBASER_VALUE						  \
	(GIC_BASER_CACHEABILITY(GICR_PROPBASER, INNER, RaWb)		| \
	 GIC_BASER_CACHEABILITY(GICR_PROPBASER, OUTER, SameAsInner)	| \
	 GIC_BASER_SHAREABILITY(GICR_PROPBASER, InnerShareable))

1516 1517 1518 1519 1520 1521 1522 1523 1524 1525 1526
static int vgic_its_create(struct kvm_device *dev, u32 type)
{
	struct vgic_its *its;

	if (type != KVM_DEV_TYPE_ARM_VGIC_ITS)
		return -ENODEV;

	its = kzalloc(sizeof(struct vgic_its), GFP_KERNEL);
	if (!its)
		return -ENOMEM;

1527 1528 1529
	mutex_init(&its->its_lock);
	mutex_init(&its->cmd_lock);

1530 1531
	its->vgic_its_base = VGIC_ADDR_UNDEF;

1532 1533 1534
	INIT_LIST_HEAD(&its->device_list);
	INIT_LIST_HEAD(&its->collection_list);

1535 1536 1537
	dev->kvm->arch.vgic.has_its = true;
	its->initialized = false;
	its->enabled = false;
1538
	its->dev = dev;
1539

1540 1541 1542 1543 1544 1545
	its->baser_device_table = INITIAL_BASER_VALUE			|
		((u64)GITS_BASER_TYPE_DEVICE << GITS_BASER_TYPE_SHIFT);
	its->baser_coll_table = INITIAL_BASER_VALUE |
		((u64)GITS_BASER_TYPE_COLLECTION << GITS_BASER_TYPE_SHIFT);
	dev->kvm->arch.vgic.propbaser = INITIAL_PROPBASER_VALUE;

1546 1547
	dev->private = its;

1548
	return vgic_its_set_abi(its, NR_ITS_ABIS - 1);
1549 1550 1551 1552
}

static void vgic_its_destroy(struct kvm_device *kvm_dev)
{
1553
	struct kvm *kvm = kvm_dev->kvm;
1554
	struct vgic_its *its = kvm_dev->private;
1555
	struct its_device *dev;
1556
	struct its_ite *ite;
1557 1558 1559 1560 1561 1562 1563 1564 1565 1566 1567 1568 1569 1570
	struct list_head *dev_cur, *dev_temp;
	struct list_head *cur, *temp;

	/*
	 * We may end up here without the lists ever having been initialized.
	 * Check this and bail out early to avoid dereferencing a NULL pointer.
	 */
	if (!its->device_list.next)
		return;

	mutex_lock(&its->its_lock);
	list_for_each_safe(dev_cur, dev_temp, &its->device_list) {
		dev = container_of(dev_cur, struct its_device, dev_list);
		list_for_each_safe(cur, temp, &dev->itt_head) {
1571 1572
			ite = (container_of(cur, struct its_ite, ite_list));
			its_free_ite(kvm, ite);
1573 1574 1575 1576 1577 1578 1579 1580 1581 1582
		}
		list_del(dev_cur);
		kfree(dev);
	}

	list_for_each_safe(cur, temp, &its->collection_list) {
		list_del(cur);
		kfree(container_of(cur, struct its_collection, coll_list));
	}
	mutex_unlock(&its->its_lock);
1583 1584 1585 1586

	kfree(its);
}

1587 1588 1589
int vgic_its_has_attr_regs(struct kvm_device *dev,
			   struct kvm_device_attr *attr)
{
1590 1591 1592 1593 1594 1595 1596 1597 1598 1599 1600 1601 1602 1603 1604 1605
	const struct vgic_register_region *region;
	gpa_t offset = attr->attr;
	int align;

	align = (offset < GITS_TYPER) || (offset >= GITS_PIDR4) ? 0x3 : 0x7;

	if (offset & align)
		return -EINVAL;

	region = vgic_find_mmio_region(its_registers,
				       ARRAY_SIZE(its_registers),
				       offset);
	if (!region)
		return -ENXIO;

	return 0;
1606 1607 1608 1609 1610 1611
}

int vgic_its_attr_regs_access(struct kvm_device *dev,
			      struct kvm_device_attr *attr,
			      u64 *reg, bool is_write)
{
1612 1613 1614 1615 1616 1617 1618 1619 1620 1621 1622 1623 1624 1625 1626 1627 1628 1629 1630 1631 1632 1633 1634 1635 1636 1637 1638 1639 1640 1641 1642 1643 1644 1645 1646 1647 1648 1649 1650 1651 1652 1653 1654 1655 1656 1657 1658 1659 1660 1661 1662 1663 1664 1665 1666 1667 1668 1669 1670 1671 1672
	const struct vgic_register_region *region;
	struct vgic_its *its;
	gpa_t addr, offset;
	unsigned int len;
	int align, ret = 0;

	its = dev->private;
	offset = attr->attr;

	/*
	 * Although the spec supports upper/lower 32-bit accesses to
	 * 64-bit ITS registers, the userspace ABI requires 64-bit
	 * accesses to all 64-bit wide registers. We therefore only
	 * support 32-bit accesses to GITS_CTLR, GITS_IIDR and GITS ID
	 * registers
	 */
	if ((offset < GITS_TYPER) || (offset >= GITS_PIDR4))
		align = 0x3;
	else
		align = 0x7;

	if (offset & align)
		return -EINVAL;

	mutex_lock(&dev->kvm->lock);

	if (IS_VGIC_ADDR_UNDEF(its->vgic_its_base)) {
		ret = -ENXIO;
		goto out;
	}

	region = vgic_find_mmio_region(its_registers,
				       ARRAY_SIZE(its_registers),
				       offset);
	if (!region) {
		ret = -ENXIO;
		goto out;
	}

	if (!lock_all_vcpus(dev->kvm)) {
		ret = -EBUSY;
		goto out;
	}

	addr = its->vgic_its_base + offset;

	len = region->access_flags & VGIC_ACCESS_64bit ? 8 : 4;

	if (is_write) {
		if (region->uaccess_its_write)
			ret = region->uaccess_its_write(dev->kvm, its, addr,
							len, *reg);
		else
			region->its_write(dev->kvm, its, addr, len, *reg);
	} else {
		*reg = region->its_read(dev->kvm, its, addr, len);
	}
	unlock_all_vcpus(dev->kvm);
out:
	mutex_unlock(&dev->kvm->lock);
	return ret;
1673 1674
}

1675 1676 1677 1678 1679 1680 1681 1682 1683 1684 1685 1686 1687 1688 1689 1690 1691 1692 1693 1694 1695 1696 1697 1698 1699 1700 1701 1702 1703 1704 1705 1706 1707 1708 1709
/**
 * vgic_its_save_tables_v0 - Save the ITS tables into guest ARM
 * according to v0 ABI
 */
static int vgic_its_save_tables_v0(struct vgic_its *its)
{
	return -ENXIO;
}

/**
 * vgic_its_restore_tables_v0 - Restore the ITS tables from guest RAM
 * to internal data structs according to V0 ABI
 *
 */
static int vgic_its_restore_tables_v0(struct vgic_its *its)
{
	return -ENXIO;
}

static int vgic_its_commit_v0(struct vgic_its *its)
{
	const struct vgic_its_abi *abi;

	abi = vgic_its_get_abi(its);
	its->baser_coll_table &= ~GITS_BASER_ENTRY_SIZE_MASK;
	its->baser_device_table &= ~GITS_BASER_ENTRY_SIZE_MASK;

	its->baser_coll_table |= (GIC_ENCODE_SZ(abi->cte_esz, 5)
					<< GITS_BASER_ENTRY_SIZE_SHIFT);

	its->baser_device_table |= (GIC_ENCODE_SZ(abi->dte_esz, 5)
					<< GITS_BASER_ENTRY_SIZE_SHIFT);
	return 0;
}

1710 1711 1712 1713 1714 1715 1716 1717 1718 1719 1720 1721 1722 1723 1724 1725
static int vgic_its_has_attr(struct kvm_device *dev,
			     struct kvm_device_attr *attr)
{
	switch (attr->group) {
	case KVM_DEV_ARM_VGIC_GRP_ADDR:
		switch (attr->attr) {
		case KVM_VGIC_ITS_ADDR_TYPE:
			return 0;
		}
		break;
	case KVM_DEV_ARM_VGIC_GRP_CTRL:
		switch (attr->attr) {
		case KVM_DEV_ARM_VGIC_CTRL_INIT:
			return 0;
		}
		break;
1726 1727
	case KVM_DEV_ARM_VGIC_GRP_ITS_REGS:
		return vgic_its_has_attr_regs(dev, attr);
1728 1729 1730 1731 1732 1733 1734 1735 1736 1737 1738 1739 1740 1741 1742 1743 1744 1745 1746 1747 1748 1749 1750 1751 1752 1753 1754 1755 1756 1757 1758 1759 1760 1761
	}
	return -ENXIO;
}

static int vgic_its_set_attr(struct kvm_device *dev,
			     struct kvm_device_attr *attr)
{
	struct vgic_its *its = dev->private;
	int ret;

	switch (attr->group) {
	case KVM_DEV_ARM_VGIC_GRP_ADDR: {
		u64 __user *uaddr = (u64 __user *)(long)attr->addr;
		unsigned long type = (unsigned long)attr->attr;
		u64 addr;

		if (type != KVM_VGIC_ITS_ADDR_TYPE)
			return -ENODEV;

		if (copy_from_user(&addr, uaddr, sizeof(addr)))
			return -EFAULT;

		ret = vgic_check_ioaddr(dev->kvm, &its->vgic_its_base,
					addr, SZ_64K);
		if (ret)
			return ret;

		its->vgic_its_base = addr;

		return 0;
	}
	case KVM_DEV_ARM_VGIC_GRP_CTRL:
		switch (attr->attr) {
		case KVM_DEV_ARM_VGIC_CTRL_INIT:
1762 1763 1764
			its->initialized = true;

			return 0;
1765 1766
		}
		break;
1767 1768 1769 1770 1771 1772 1773 1774 1775
	case KVM_DEV_ARM_VGIC_GRP_ITS_REGS: {
		u64 __user *uaddr = (u64 __user *)(long)attr->addr;
		u64 reg;

		if (get_user(reg, uaddr))
			return -EFAULT;

		return vgic_its_attr_regs_access(dev, attr, &reg, true);
	}
1776 1777 1778 1779 1780 1781 1782 1783 1784 1785 1786 1787 1788 1789 1790 1791 1792 1793 1794 1795
	}
	return -ENXIO;
}

static int vgic_its_get_attr(struct kvm_device *dev,
			     struct kvm_device_attr *attr)
{
	switch (attr->group) {
	case KVM_DEV_ARM_VGIC_GRP_ADDR: {
		struct vgic_its *its = dev->private;
		u64 addr = its->vgic_its_base;
		u64 __user *uaddr = (u64 __user *)(long)attr->addr;
		unsigned long type = (unsigned long)attr->attr;

		if (type != KVM_VGIC_ITS_ADDR_TYPE)
			return -ENODEV;

		if (copy_to_user(uaddr, &addr, sizeof(addr)))
			return -EFAULT;
		break;
1796 1797 1798 1799 1800 1801 1802 1803 1804 1805 1806
	}
	case KVM_DEV_ARM_VGIC_GRP_ITS_REGS: {
		u64 __user *uaddr = (u64 __user *)(long)attr->addr;
		u64 reg;
		int ret;

		ret = vgic_its_attr_regs_access(dev, attr, &reg, false);
		if (ret)
			return ret;
		return put_user(reg, uaddr);
	}
1807 1808 1809 1810 1811 1812 1813 1814 1815 1816 1817 1818 1819 1820 1821 1822 1823 1824 1825 1826 1827
	default:
		return -ENXIO;
	}

	return 0;
}

static struct kvm_device_ops kvm_arm_vgic_its_ops = {
	.name = "kvm-arm-vgic-its",
	.create = vgic_its_create,
	.destroy = vgic_its_destroy,
	.set_attr = vgic_its_set_attr,
	.get_attr = vgic_its_get_attr,
	.has_attr = vgic_its_has_attr,
};

int kvm_vgic_register_its_device(void)
{
	return kvm_register_device_ops(&kvm_arm_vgic_its_ops,
				       KVM_DEV_TYPE_ARM_VGIC_ITS);
}
1828 1829 1830 1831 1832 1833 1834 1835 1836 1837 1838 1839 1840 1841 1842 1843 1844 1845 1846 1847 1848 1849 1850 1851 1852 1853 1854

/*
 * Registers all ITSes with the kvm_io_bus framework.
 * To follow the existing VGIC initialization sequence, this has to be
 * done as late as possible, just before the first VCPU runs.
 */
int vgic_register_its_iodevs(struct kvm *kvm)
{
	struct kvm_device *dev;
	int ret = 0;

	list_for_each_entry(dev, &kvm->devices, vm_node) {
		if (dev->ops != &kvm_arm_vgic_its_ops)
			continue;

		ret = vgic_register_its_iodev(kvm, dev->private);
		if (ret)
			return ret;
		/*
		 * We don't need to care about tearing down previously
		 * registered ITSes, as the kvm_io_bus framework removes
		 * them for us if the VM gets destroyed.
		 */
	}

	return ret;
}