Commit f94591e2 authored by Eric Auger's avatar Eric Auger Committed by Christoffer Dall
Browse files

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: default avatarEric Auger <eric.auger@linaro.org>
Signed-off-by: default avatarAndre Przywara <andre.przywara@arm.com>
Reviewed-by: default avatarChristoffer Dall <christoffer.dall@linaro.org>
parent e5c30294

virt/kvm/arm/vgic/vgic-kvm-device.c

+51 −2
Original line number Diff line number Diff line
@@ -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);

	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);

	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:

virt/kvm/arm/vgic/vgic-mmio-v2.c

+38 −0
Original line number Diff line number Diff line
@@ -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;

}

virt/kvm/arm/vgic/vgic.h

+1 −0
Original line number Diff line number Diff line
@@ -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);