KVM: arm/arm64: vgic-new: vgic_kvm_device: access to VGIC registers

This patch implements the switches for KVM_DEV_ARM_VGIC_GRP_DIST_REGS
and KVM_DEV_ARM_VGIC_GRP_CPU_REGS API which allows the userspace to
access VGIC registers.

Signed-off-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
This commit is contained in:
Eric Auger 2015-12-21 17:34:52 +01:00 committed by Christoffer Dall
parent e5c3029467
commit f94591e2e6
3 changed files with 90 additions and 2 deletions

View File

@ -226,6 +226,21 @@ void kvm_register_vgic_device(unsigned long type)
}
}
/** vgic_attr_regs_access: allows user space to read/write VGIC registers
*
* @dev: kvm device handle
* @attr: kvm device attribute
* @reg: address the value is read or written
* @is_write: write flag
*
*/
static int vgic_attr_regs_access(struct kvm_device *dev,
struct kvm_device_attr *attr,
u32 *reg, bool is_write)
{
return -ENXIO;
}
/* V2 ops */
static int vgic_v2_set_attr(struct kvm_device *dev,
@ -234,8 +249,23 @@ static int vgic_v2_set_attr(struct kvm_device *dev,
int ret;
ret = vgic_set_common_attr(dev, attr);
return ret;
if (ret != -ENXIO)
return ret;
switch (attr->group) {
case KVM_DEV_ARM_VGIC_GRP_DIST_REGS:
case KVM_DEV_ARM_VGIC_GRP_CPU_REGS: {
u32 __user *uaddr = (u32 __user *)(long)attr->addr;
u32 reg;
if (get_user(reg, uaddr))
return -EFAULT;
return vgic_attr_regs_access(dev, attr, &reg, true);
}
}
return -ENXIO;
}
static int vgic_v2_get_attr(struct kvm_device *dev,
@ -244,7 +274,23 @@ static int vgic_v2_get_attr(struct kvm_device *dev,
int ret;
ret = vgic_get_common_attr(dev, attr);
return ret;
if (ret != -ENXIO)
return ret;
switch (attr->group) {
case KVM_DEV_ARM_VGIC_GRP_DIST_REGS:
case KVM_DEV_ARM_VGIC_GRP_CPU_REGS: {
u32 __user *uaddr = (u32 __user *)(long)attr->addr;
u32 reg = 0;
ret = vgic_attr_regs_access(dev, attr, &reg, false);
if (ret)
return ret;
return put_user(reg, uaddr);
}
}
return -ENXIO;
}
static int vgic_v2_has_attr(struct kvm_device *dev,
@ -258,6 +304,9 @@ static int vgic_v2_has_attr(struct kvm_device *dev,
return 0;
}
break;
case KVM_DEV_ARM_VGIC_GRP_DIST_REGS:
case KVM_DEV_ARM_VGIC_GRP_CPU_REGS:
return vgic_v2_has_attr_regs(dev, attr);
case KVM_DEV_ARM_VGIC_GRP_NR_IRQS:
return 0;
case KVM_DEV_ARM_VGIC_GRP_CTRL:

View File

@ -258,3 +258,41 @@ unsigned int vgic_v2_init_dist_iodev(struct vgic_io_device *dev)
return SZ_4K;
}
int vgic_v2_has_attr_regs(struct kvm_device *dev, struct kvm_device_attr *attr)
{
int nr_irqs = dev->kvm->arch.vgic.nr_spis + VGIC_NR_PRIVATE_IRQS;
const struct vgic_register_region *regions;
gpa_t addr;
int nr_regions, i, len;
addr = attr->attr & KVM_DEV_ARM_VGIC_OFFSET_MASK;
switch (attr->group) {
case KVM_DEV_ARM_VGIC_GRP_DIST_REGS:
regions = vgic_v2_dist_registers;
nr_regions = ARRAY_SIZE(vgic_v2_dist_registers);
break;
case KVM_DEV_ARM_VGIC_GRP_CPU_REGS:
return -ENXIO; /* TODO: describe CPU i/f regs also */
default:
return -ENXIO;
}
/* We only support aligned 32-bit accesses. */
if (addr & 3)
return -ENXIO;
for (i = 0; i < nr_regions; i++) {
if (regions[i].bits_per_irq)
len = (regions[i].bits_per_irq * nr_irqs) / 8;
else
len = regions[i].len;
if (regions[i].reg_offset <= addr &&
regions[i].reg_offset + len > addr)
return 0;
}
return -ENXIO;
}

View File

@ -37,6 +37,7 @@ 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);
void vgic_v2_clear_lr(struct kvm_vcpu *vcpu, int lr);
void vgic_v2_set_underflow(struct kvm_vcpu *vcpu);
int vgic_v2_has_attr_regs(struct kvm_device *dev, struct kvm_device_attr *attr);
int vgic_register_dist_iodev(struct kvm *kvm, gpa_t dist_base_address,
enum vgic_type);