[RFC PATCH 30/45] KVM: arm/arm64: vgic-new: vgic_kvm_device: KVM_DEV_ARM_VGIC_GRP_NR_IRQS

Andre Przywara
2016-03-25T02:05:11Z

From: Eric Auger <eric.auger@linaro.org>

This patch implements the KVM_DEV_ARM_VGIC_GRP_NR_IRQS group. This
modality is supported by both VGIC V2 and V3 KVM device as will be
other groups, hence the introduction of common helpers.

Signed-off-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
---
virt/kvm/arm/vgic/vgic_kvm_device.c | 83 +++++++++++++++++++++++++++++++++++--
1 file changed, 79 insertions(+), 4 deletions(-)

diff --git a/virt/kvm/arm/vgic/vgic_kvm_device.c b/virt/kvm/arm/vgic/vgic_kvm_device.c
index 7c665f9..c96549b 100644
--- a/virt/kvm/arm/vgic/vgic_kvm_device.c
+++ b/virt/kvm/arm/vgic/vgic_kvm_device.c
@@ -15,9 +15,69 @@
*/
#include <linux/kvm_host.h>
#include <kvm/vgic/vgic.h>
+#include <linux/uaccess.h>
+#include "vgic.h"

/* common helpers */

+static int vgic_set_common_attr(struct kvm_device *dev,
+ struct kvm_device_attr *attr)
+{
+ switch (attr->group) {
+ case KVM_DEV_ARM_VGIC_GRP_NR_IRQS: {
+ u32 __user *uaddr = (u32 __user *)(long)attr->addr;
+ u32 val;
+ int ret = 0;
+
+ if (get_user(val, uaddr))
+ return -EFAULT;
+
+ /*
+ * We require:
+ * - at least 32 SPIs on top of the 16 SGIs and 16 PPIs
+ * - at most 1024 interrupts
+ * - a multiple of 32 interrupts
+ */
+ if (val < (VGIC_NR_PRIVATE_IRQS + 32) ||
+ val > VGIC_MAX_RESERVED ||
+ (val & 31))
+ return -EINVAL;
+
+ mutex_lock(&dev->kvm->lock);
+
+ if (vgic_ready(dev->kvm) || dev->kvm->arch.vgic.nr_spis)
+ ret = -EBUSY;
+ else
+ dev->kvm->arch.vgic.nr_spis =
+ val - VGIC_NR_PRIVATE_IRQS;
+
+ mutex_unlock(&dev->kvm->lock);
+
+ return ret;
+ }
+ }
+
+ return -ENXIO;
+}
+
+static int vgic_get_common_attr(struct kvm_device *dev,
+ struct kvm_device_attr *attr)
+{
+ int r = -ENXIO;
+
+ switch (attr->group) {
+ case KVM_DEV_ARM_VGIC_GRP_NR_IRQS: {
+ u32 __user *uaddr = (u32 __user *)(long)attr->addr;
+
+ r = put_user(dev->kvm->arch.vgic.nr_spis +
+ VGIC_NR_PRIVATE_IRQS, uaddr);
+ break;
+ }
+ }
+
+ return r;
+}
+
static int vgic_create(struct kvm_device *dev, u32 type)
{
return kvm_vgic_create(dev->kvm, type);
@@ -49,18 +109,29 @@ void kvm_register_vgic_device(unsigned long type)
static int vgic_v2_set_attr(struct kvm_device *dev,
struct kvm_device_attr *attr)
{
- return -ENXIO;
+ int ret;
+
+ ret = vgic_set_common_attr(dev, attr);
+ return ret;
+
}

static int vgic_v2_get_attr(struct kvm_device *dev,
struct kvm_device_attr *attr)
{
- return -ENXIO;
+ int ret;
+
+ ret = vgic_get_common_attr(dev, attr);
+ return ret;
}

static int vgic_v2_has_attr(struct kvm_device *dev,
struct kvm_device_attr *attr)
{
+ switch (attr->group) {
+ case KVM_DEV_ARM_VGIC_GRP_NR_IRQS:
+ return 0;
+ }
return -ENXIO;
}

@@ -80,18 +151,22 @@ struct kvm_device_ops kvm_arm_vgic_v2_ops = {
static int vgic_v3_set_attr(struct kvm_device *dev,
struct kvm_device_attr *attr)
{
- return -ENXIO;
+ return vgic_set_common_attr(dev, attr);
}

static int vgic_v3_get_attr(struct kvm_device *dev,
struct kvm_device_attr *attr)
{
- return -ENXIO;
+ return vgic_get_common_attr(dev, attr);
}

static int vgic_v3_has_attr(struct kvm_device *dev,
struct kvm_device_attr *attr)
{
+ switch (attr->group) {
+ case KVM_DEV_ARM_VGIC_GRP_NR_IRQS:
+ return 0;
+ }
return -ENXIO;
}

--
2.7.3