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 initialize the ITS data structure and
add this ITS to a linked list. Userland is expected to set the frame
address using an ioctl during the VM initialization process, this will
be used to pick the right ITS for a particular device or MMIO access.
Signed-off-by: Andre Przywara <andre.przywara@xxxxxxx>
---
Documentation/virtual/kvm/devices/arm-vgic.txt | 23 ++++-
arch/arm/include/asm/kvm_host.h | 3 +
arch/arm/kvm/arm.c | 3 +
arch/arm64/include/asm/kvm_host.h | 2 +
arch/arm64/include/uapi/asm/kvm.h | 2 +
include/kvm/vgic/vgic.h | 2 +
include/uapi/linux/kvm.h | 2 +
virt/kvm/arm/vgic/vgic-init.c | 13 +++
virt/kvm/arm/vgic/vgic-its.c | 121 +++++++++++++++++++++++++
virt/kvm/arm/vgic/vgic-kvm-device.c | 7 +-
virt/kvm/arm/vgic/vgic-mmio-v3.c | 2 +-
virt/kvm/arm/vgic/vgic.h | 9 ++
12 files changed, 182 insertions(+), 7 deletions(-)
diff --git a/Documentation/virtual/kvm/devices/arm-vgic.txt b/Documentation/virtual/kvm/devices/arm-vgic.txt
index 59541d4..d263fffd 100644
--- a/Documentation/virtual/kvm/devices/arm-vgic.txt
+++ b/Documentation/virtual/kvm/devices/arm-vgic.txt
@@ -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 +45,15 @@ 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.
+ This address region is solely for the guest to access the ITS control
+ registers and does not cover the ITS translation register.
+ Only valid for KVM_DEV_TYPE_ARM_VGIC_ITS.
+ This address needs to be 64K aligned and the region covers 64K.
KVM_DEV_ARM_VGIC_GRP_DIST_REGS
Attributes:
diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h
index 3c40facd..917a330 100644
--- a/arch/arm/include/asm/kvm_host.h
+++ b/arch/arm/include/asm/kvm_host.h
@@ -69,6 +69,9 @@ struct kvm_arch {
/* Interrupt controller */
struct vgic_dist vgic;
+ /* List of virtual ITS MSI controllers */
+ struct list_head vits_list;
+
int max_vcpus;
};
diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c
index a268c85..bfe1af2 100644
--- a/arch/arm/kvm/arm.c
+++ b/arch/arm/kvm/arm.c
@@ -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>
@@ -126,7 +127,9 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
if (ret)
goto out_free_stage2_pgd;
+ INIT_LIST_HEAD(&kvm->arch.vits_list);
kvm_vgic_early_init(kvm);
+
kvm_timer_init(kvm);
/* Mark the initial VMID generation invalid */
diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h
index ebe8904..b4b1814 100644
--- a/arch/arm64/include/asm/kvm_host.h
+++ b/arch/arm64/include/asm/kvm_host.h
@@ -68,6 +68,8 @@ struct kvm_arch {
/* Interrupt controller */
struct vgic_dist vgic;
+ /* List of virtual ITS MSI controllers */
+ struct list_head vits_list;
/* Timer */
struct arch_timer_kvm timer;
diff --git a/arch/arm64/include/uapi/asm/kvm.h b/arch/arm64/include/uapi/asm/kvm.h
index f209ea1..f8c257b 100644
--- a/arch/arm64/include/uapi/asm/kvm.h
+++ b/arch/arm64/include/uapi/asm/kvm.h
@@ -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 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 */
diff --git a/include/kvm/vgic/vgic.h b/include/kvm/vgic/vgic.h
index 6a7f5e4..8cf8018f 100644
--- a/include/kvm/vgic/vgic.h
+++ b/include/kvm/vgic/vgic.h
@@ -117,6 +117,8 @@ struct vgic_io_device {
};
struct vgic_its {
+ struct list_head its_list;
+
/* The base address of the ITS control register frame */
gpa_t vgic_its_base;
diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
index 7de96f5..d8c4c32 100644
--- a/include/uapi/linux/kvm.h
+++ b/include/uapi/linux/kvm.h
@@ -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,
};
diff --git a/virt/kvm/arm/vgic/vgic-init.c b/virt/kvm/arm/vgic/vgic-init.c
index 90cae48..adf3c1d 100644
--- a/virt/kvm/arm/vgic/vgic-init.c
+++ b/virt/kvm/arm/vgic/vgic-init.c
@@ -239,6 +239,7 @@ static void kvm_vgic_vcpu_init(struct kvm_vcpu *vcpu)
int vgic_init(struct kvm *kvm)
{
struct vgic_dist *dist = &kvm->arch.vgic;
+ struct vgic_its *its;
struct kvm_vcpu *vcpu;
int ret = 0, i;
@@ -253,6 +254,12 @@ int vgic_init(struct kvm *kvm)
if (ret)
goto out;
+ list_for_each_entry(its, &kvm->arch.vits_list, its_list) {
+ ret = vits_init(kvm, its);
+ if (ret)
+ goto out;
+ }
+
kvm_for_each_vcpu(i, vcpu, kvm)
kvm_vgic_vcpu_init(vcpu);
@@ -286,10 +293,16 @@ void kvm_vgic_vcpu_destroy(struct kvm_vcpu *vcpu)
void kvm_vgic_destroy(struct kvm *kvm)
{
struct kvm_vcpu *vcpu;
+ struct vgic_its *its, *next;
int i;
kvm_vgic_dist_destroy(kvm);
+ list_for_each_entry_safe(its, next, &kvm->arch.vits_list, its_list) {
+ vits_destroy(kvm, its);
+ kfree(its);
+ }
+
kvm_for_each_vcpu(i, vcpu, kvm)
kvm_vgic_vcpu_destroy(vcpu);
}
diff --git a/virt/kvm/arm/vgic/vgic-its.c b/virt/kvm/arm/vgic/vgic-its.c
index 61f3b8e..61f550d 100644
--- a/virt/kvm/arm/vgic/vgic-its.c
+++ b/virt/kvm/arm/vgic/vgic-its.c
@@ -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>
@@ -82,3 +83,123 @@ void vits_destroy(struct kvm *kvm, struct vgic_its *its)
its->enabled = false;
}
+
+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;
+
+ spin_lock_init(&its->lock);
+
+ its->vgic_its_base = VGIC_ADDR_UNDEF;
+
+ its->enabled = false;
+
+ dev->private = its;
+
+ list_add_tail(&its->its_list, &dev->kvm->arch.vits_list);
+
+ return 0;
+}
+
+static void vgic_its_destroy(struct kvm_device *dev)
+{
+ struct vgic_its *its = dev->private;
+
+ list_del(&its->its_list);
+
+ vits_destroy(dev->kvm, its);
+
+ 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;
+ }
+ return -ENXIO;
+}
+
+static int vgic_its_set_attr(struct kvm_device *dev,
+ struct kvm_device_attr *attr)
+{
+ int ret;
+
+ switch (attr->group) {
+ case KVM_DEV_ARM_VGIC_GRP_ADDR: {
+ struct vgic_its *its = dev->private;
+ 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;
+ }
+ }
+
+ 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;
+}
+
+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);
+}
diff --git a/virt/kvm/arm/vgic/vgic-kvm-device.c b/virt/kvm/arm/vgic/vgic-kvm-device.c
index 2f24f13..1813f93 100644
--- a/virt/kvm/arm/vgic/vgic-kvm-device.c
+++ b/virt/kvm/arm/vgic/vgic-kvm-device.c
@@ -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;
@@ -223,6 +223,9 @@ int kvm_register_vgic_device(unsigned long type)
case KVM_DEV_TYPE_ARM_VGIC_V3:
ret = kvm_register_device_ops(&kvm_arm_vgic_v3_ops,
KVM_DEV_TYPE_ARM_VGIC_V3);
+ if (ret)
+ break;
+ ret = kvm_vgic_register_its_device();
break;
#endif
}
diff --git a/virt/kvm/arm/vgic/vgic-mmio-v3.c b/virt/kvm/arm/vgic/vgic-mmio-v3.c
index 2eb9f0e..d3511d6 100644
--- a/virt/kvm/arm/vgic/vgic-mmio-v3.c
+++ b/virt/kvm/arm/vgic/vgic-mmio-v3.c
@@ -46,7 +46,7 @@ bool vgic_has_its(struct kvm *kvm)
if (dist->vgic_model != KVM_DEV_TYPE_ARM_VGIC_V3)
return false;
- return false;
+ return !list_empty(&kvm->arch.vits_list);
}
static unsigned long vgic_mmio_read_v3_misc(struct kvm_vcpu *vcpu,
diff --git a/virt/kvm/arm/vgic/vgic.h b/virt/kvm/arm/vgic/vgic.h
index 0baad03..66578d2 100644
--- a/virt/kvm/arm/vgic/vgic.h
+++ b/virt/kvm/arm/vgic/vgic.h
@@ -41,6 +41,9 @@ struct vgic_irq *vgic_get_irq(struct kvm *kvm, struct kvm_vcpu *vcpu,
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);
@@ -74,6 +77,7 @@ int vgic_register_redist_iodevs(struct kvm *kvm, gpa_t dist_base_address);
bool vgic_has_its(struct kvm *kvm);
int vits_init(struct kvm *kvm, struct vgic_its *its);
void vits_destroy(struct kvm *kvm, struct vgic_its *its);
+int kvm_vgic_register_its_device(void);
#else
static inline void vgic_v3_process_maintenance(struct kvm_vcpu *vcpu)
{
@@ -139,6 +143,11 @@ static int vits_init(struct kvm *kvm, struct vgic_its *its)
static inline void vits_destroy(struct kvm *kvm, struct vgic_its *its)
{
}
+
+static int kvm_vgic_register_its_device(void)
+{
+ return -ENODEV;
+}
#endif
int kvm_register_vgic_device(unsigned long type);
--
2.8.2
--
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