KVM: arm64: vgic-its: Introduce new KVM ITS device

Introduce a new KVM device that represents an ARM Interrupt Translation
Service (ITS) controller. Since there can be multiple of this per guest,
we can't piggy back on the existing GICv3 distributor device, but create
a new type of KVM device.
On the KVM_CREATE_DEVICE ioctl we allocate and initialize the ITS data
structure and store the pointer in the kvm_device data.
Upon an explicit init ioctl from userland (after having setup the MMIO
address) we register the handlers with the kvm_io_bus framework.
Any reference to an ITS thus has to go via this interface.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Tested-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
This commit is contained in:
Andre Przywara 2016-07-15 12:43:31 +01:00 committed by Marc Zyngier
parent 59c5ab4098
commit 1085fdc68c
9 changed files with 168 additions and 9 deletions

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@ -4,16 +4,22 @@ ARM Virtual Generic Interrupt Controller (VGIC)
Device types supported:
KVM_DEV_TYPE_ARM_VGIC_V2 ARM Generic Interrupt Controller v2.0
KVM_DEV_TYPE_ARM_VGIC_V3 ARM Generic Interrupt Controller v3.0
KVM_DEV_TYPE_ARM_VGIC_ITS ARM Interrupt Translation Service Controller
Only one VGIC instance may be instantiated through either this API or the
legacy KVM_CREATE_IRQCHIP api. The created VGIC will act as the VM interrupt
controller, requiring emulated user-space devices to inject interrupts to the
VGIC instead of directly to CPUs.
Only one VGIC instance of the V2/V3 types above may be instantiated through
either this API or the legacy KVM_CREATE_IRQCHIP api. The created VGIC will
act as the VM interrupt controller, requiring emulated user-space devices to
inject interrupts to the VGIC instead of directly to CPUs.
Creating a guest GICv3 device requires a host GICv3 as well.
GICv3 implementations with hardware compatibility support allow a guest GICv2
as well.
Creating a virtual ITS controller requires a host GICv3 (but does not depend
on having physical ITS controllers).
There can be multiple ITS controllers per guest, each of them has to have
a separate, non-overlapping MMIO region.
Groups:
KVM_DEV_ARM_VGIC_GRP_ADDR
Attributes:
@ -39,6 +45,13 @@ Groups:
Only valid for KVM_DEV_TYPE_ARM_VGIC_V3.
This address needs to be 64K aligned.
KVM_VGIC_V3_ADDR_TYPE_ITS (rw, 64-bit)
Base address in the guest physical address space of the GICv3 ITS
control register frame. The ITS allows MSI(-X) interrupts to be
injected into guests. This extension is optional. If the kernel
does not support the ITS, the call returns -ENODEV.
Only valid for KVM_DEV_TYPE_ARM_VGIC_ITS.
This address needs to be 64K aligned and the region covers 128K.
KVM_DEV_ARM_VGIC_GRP_DIST_REGS
Attributes:
@ -109,8 +122,8 @@ Groups:
KVM_DEV_ARM_VGIC_GRP_CTRL
Attributes:
KVM_DEV_ARM_VGIC_CTRL_INIT
request the initialization of the VGIC, no additional parameter in
kvm_device_attr.addr.
request the initialization of the VGIC or ITS, no additional parameter
in kvm_device_attr.addr.
Errors:
-ENXIO: VGIC not properly configured as required prior to calling
this attribute

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@ -20,6 +20,7 @@
#include <linux/errno.h>
#include <linux/err.h>
#include <linux/kvm_host.h>
#include <linux/list.h>
#include <linux/module.h>
#include <linux/vmalloc.h>
#include <linux/fs.h>

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@ -87,9 +87,11 @@ struct kvm_regs {
/* Supported VGICv3 address types */
#define KVM_VGIC_V3_ADDR_TYPE_DIST 2
#define KVM_VGIC_V3_ADDR_TYPE_REDIST 3
#define KVM_VGIC_ITS_ADDR_TYPE 4
#define KVM_VGIC_V3_DIST_SIZE SZ_64K
#define KVM_VGIC_V3_REDIST_SIZE (2 * SZ_64K)
#define KVM_VGIC_V3_ITS_SIZE (2 * SZ_64K)
#define KVM_ARM_VCPU_POWER_OFF 0 /* CPU is started in OFF state */
#define KVM_ARM_VCPU_EL1_32BIT 1 /* CPU running a 32bit VM */

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@ -134,6 +134,7 @@ struct vgic_its {
gpa_t vgic_its_base;
bool enabled;
bool initialized;
struct vgic_io_device iodev;
};
@ -167,6 +168,8 @@ struct vgic_dist {
struct vgic_io_device dist_iodev;
bool has_its;
/*
* Contains the attributes and gpa of the LPI configuration table.
* Since we report GICR_TYPER.CommonLPIAff as 0b00, we can share

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@ -1077,6 +1077,8 @@ enum kvm_device_type {
#define KVM_DEV_TYPE_FLIC KVM_DEV_TYPE_FLIC
KVM_DEV_TYPE_ARM_VGIC_V3,
#define KVM_DEV_TYPE_ARM_VGIC_V3 KVM_DEV_TYPE_ARM_VGIC_V3
KVM_DEV_TYPE_ARM_VGIC_ITS,
#define KVM_DEV_TYPE_ARM_VGIC_ITS KVM_DEV_TYPE_ARM_VGIC_ITS
KVM_DEV_TYPE_MAX,
};

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@ -21,6 +21,7 @@
#include <linux/kvm.h>
#include <linux/kvm_host.h>
#include <linux/interrupt.h>
#include <linux/uaccess.h>
#include <linux/irqchip/arm-gic-v3.h>
@ -84,6 +85,9 @@ static int vgic_its_init_its(struct kvm *kvm, struct vgic_its *its)
struct vgic_io_device *iodev = &its->iodev;
int ret;
if (its->initialized)
return 0;
if (IS_VGIC_ADDR_UNDEF(its->vgic_its_base))
return -ENXIO;
@ -99,5 +103,136 @@ static int vgic_its_init_its(struct kvm *kvm, struct vgic_its *its)
KVM_VGIC_V3_ITS_SIZE, &iodev->dev);
mutex_unlock(&kvm->slots_lock);
if (!ret)
its->initialized = true;
return ret;
}
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;
its->vgic_its_base = VGIC_ADDR_UNDEF;
dev->kvm->arch.vgic.has_its = true;
its->initialized = false;
its->enabled = false;
dev->private = its;
return 0;
}
static void vgic_its_destroy(struct kvm_device *kvm_dev)
{
struct vgic_its *its = kvm_dev->private;
kfree(its);
}
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;
}
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 (its->initialized)
return -EBUSY;
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:
return vgic_its_init_its(dev->kvm, its);
}
break;
}
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;
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);
}

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@ -21,8 +21,8 @@
/* common helpers */
static int vgic_check_ioaddr(struct kvm *kvm, phys_addr_t *ioaddr,
phys_addr_t addr, phys_addr_t alignment)
int vgic_check_ioaddr(struct kvm *kvm, phys_addr_t *ioaddr,
phys_addr_t addr, phys_addr_t alignment)
{
if (addr & ~KVM_PHYS_MASK)
return -E2BIG;

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@ -49,7 +49,7 @@ bool vgic_has_its(struct kvm *kvm)
if (dist->vgic_model != KVM_DEV_TYPE_ARM_VGIC_V3)
return false;
return false;
return dist->has_its;
}
static unsigned long vgic_mmio_read_v3_misc(struct kvm_vcpu *vcpu,

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@ -42,6 +42,9 @@ void vgic_put_irq(struct kvm *kvm, struct vgic_irq *irq);
bool vgic_queue_irq_unlock(struct kvm *kvm, struct vgic_irq *irq);
void vgic_kick_vcpus(struct kvm *kvm);
int vgic_check_ioaddr(struct kvm *kvm, phys_addr_t *ioaddr,
phys_addr_t addr, phys_addr_t alignment);
void vgic_v2_process_maintenance(struct kvm_vcpu *vcpu);
void vgic_v2_fold_lr_state(struct kvm_vcpu *vcpu);
void vgic_v2_populate_lr(struct kvm_vcpu *vcpu, struct vgic_irq *irq, int lr);