[PATCH v3 41/55] KVM: arm/arm64: vgic-new: vgic_kvm_device: implement kvm_vgic_addr

[Christoffer Dall]

On Fri, May 06, 2016 at 11:45:54AM +0100, Andre Przywara wrote:
> From: Eric Auger <eric.auger at linaro.org>
> 
> kvm_vgic_addr is used by the userspace to set the base address of
> the following register regions, as seen by the guest:
> - distributor(v2 and v3),
> - re-distributors (v3),
> - CPU interface (v2).
> 
> Signed-off-by: Eric Auger <eric.auger at linaro.org>
> Signed-off-by: Andre Przywara <andre.przywara at arm.com>
> ---
>  include/kvm/vgic/vgic.h             |   2 +
>  virt/kvm/arm/vgic/vgic-kvm-device.c | 112 ++++++++++++++++++++++++++++++++++++
>  virt/kvm/arm/vgic/vgic.h            |   3 +
>  3 files changed, 117 insertions(+)
> 
> diff --git a/include/kvm/vgic/vgic.h b/include/kvm/vgic/vgic.h
> index 2c43eb8..73cab36 100644
> --- a/include/kvm/vgic/vgic.h
> +++ b/include/kvm/vgic/vgic.h
> @@ -194,6 +194,8 @@ struct vgic_cpu {
>  	u64 live_lrs;
>  };
>  
> +int kvm_vgic_addr(struct kvm *kvm, unsigned long type, u64 *addr, bool write);
> +
>  int kvm_vgic_inject_irq(struct kvm *kvm, int cpuid, unsigned int intid,
>  			bool level);
>  
> diff --git a/virt/kvm/arm/vgic/vgic-kvm-device.c b/virt/kvm/arm/vgic/vgic-kvm-device.c
> index e153f12..493e941 100644
> --- a/virt/kvm/arm/vgic/vgic-kvm-device.c
> +++ b/virt/kvm/arm/vgic/vgic-kvm-device.c
> @@ -16,10 +16,122 @@
>  #include <linux/kvm_host.h>
>  #include <kvm/arm_vgic.h>
>  #include <linux/uaccess.h>
> +#include <asm/kvm_mmu.h>
>  #include "vgic.h"
>  
>  /* common helpers */
>  
> +static int vgic_ioaddr_overlap(struct kvm *kvm)
> +{
> +	phys_addr_t dist = kvm->arch.vgic.vgic_dist_base;
> +	phys_addr_t cpu = kvm->arch.vgic.vgic_cpu_base;
> +
> +	if (IS_VGIC_ADDR_UNDEF(dist) || IS_VGIC_ADDR_UNDEF(cpu))
> +		return 0;
> +	if ((dist <= cpu && dist + KVM_VGIC_V2_DIST_SIZE > cpu) ||
> +	    (cpu <= dist && cpu + KVM_VGIC_V2_CPU_SIZE > dist))
> +		return -EBUSY;
> +	return 0;
> +}
> +
> +static int vgic_ioaddr_assign(struct kvm *kvm, phys_addr_t *ioaddr,
> +			      phys_addr_t addr, phys_addr_t size)
> +{
> +	int ret;
> +
> +	if (addr & ~KVM_PHYS_MASK)
> +		return -E2BIG;
> +
> +	if (addr & (SZ_4K - 1))
> +		return -EINVAL;
> +
> +	if (!IS_VGIC_ADDR_UNDEF(*ioaddr))
> +		return -EEXIST;
> +	if (addr + size < addr)
> +		return -EINVAL;
> +
> +	*ioaddr = addr;
> +	ret = vgic_ioaddr_overlap(kvm);
> +	if (ret)
> +		*ioaddr = VGIC_ADDR_UNDEF;
> +
> +	return ret;
> +}
> +
> +/**
> + * kvm_vgic_addr - set or get vgic VM base addresses
> + * @kvm:   pointer to the vm struct
> + * @type:  the VGIC addr type, one of KVM_VGIC_V[23]_ADDR_TYPE_XXX
> + * @addr:  pointer to address value
> + * @write: if true set the address in the VM address space, if false read the
> + *          address
> + *
> + * Set or get the vgic base addresses for the distributor and the virtual CPU
> + * interface in the VM physical address space.  These addresses are properties
> + * of the emulated core/SoC and therefore user space initially knows this
> + * information.
> + */
> +int kvm_vgic_addr(struct kvm *kvm, unsigned long type, u64 *addr, bool write)
> +{
> +	int r = 0;
> +	struct vgic_dist *vgic = &kvm->arch.vgic;
> +	int type_needed;
> +	phys_addr_t *addr_ptr, block_size;
> +	phys_addr_t alignment;
> +
> +	mutex_lock(&kvm->lock);
> +	switch (type) {
> +	case KVM_VGIC_V2_ADDR_TYPE_DIST:
> +		type_needed = KVM_DEV_TYPE_ARM_VGIC_V2;
> +		addr_ptr = &vgic->vgic_dist_base;
> +		block_size = KVM_VGIC_V2_DIST_SIZE;
> +		alignment = SZ_4K;
> +		break;
> +	case KVM_VGIC_V2_ADDR_TYPE_CPU:
> +		type_needed = KVM_DEV_TYPE_ARM_VGIC_V2;
> +		addr_ptr = &vgic->vgic_cpu_base;
> +		block_size = KVM_VGIC_V2_CPU_SIZE;
> +		alignment = SZ_4K;
> +		break;
> +#ifdef CONFIG_KVM_ARM_VGIC_V3
> +	case KVM_VGIC_V3_ADDR_TYPE_DIST:
> +		type_needed = KVM_DEV_TYPE_ARM_VGIC_V3;
> +		addr_ptr = &vgic->vgic_dist_base;
> +		block_size = KVM_VGIC_V3_DIST_SIZE;
> +		alignment = SZ_64K;
> +		break;
> +	case KVM_VGIC_V3_ADDR_TYPE_REDIST:
> +		type_needed = KVM_DEV_TYPE_ARM_VGIC_V3;
> +		addr_ptr = &vgic->vgic_redist_base;
> +		block_size = KVM_VGIC_V3_REDIST_SIZE;
> +		alignment = SZ_64K;
> +		break;
> +#endif
> +	default:
> +		r = -ENODEV;
> +		goto out;
> +	}
> +
> +	if (vgic->vgic_model != type_needed) {
> +		r = -ENODEV;
> +		goto out;
> +	}
> +
> +	if (write) {
> +		if (!IS_ALIGNED(*addr, alignment))
> +			r = -EINVAL;
> +		else
> +			r = vgic_ioaddr_assign(kvm, addr_ptr,
> +					       *addr, block_size);
> +	} else {
> +		*addr = *addr_ptr;
> +	}
> +
> +out:
> +	mutex_unlock(&kvm->lock);
> +	return r;
> +}
> +
>  static int vgic_set_common_attr(struct kvm_device *dev,
>  				struct kvm_device_attr *attr)
>  {
> diff --git a/virt/kvm/arm/vgic/vgic.h b/virt/kvm/arm/vgic/vgic.h
> index e7c66a5..c44ee01 100644
> --- a/virt/kvm/arm/vgic/vgic.h
> +++ b/virt/kvm/arm/vgic/vgic.h
> @@ -19,6 +19,9 @@
>  #define PRODUCT_ID_KVM		0x4b	/* ASCII code K */
>  #define IMPLEMENTER_ARM		0x43b
>  
> +#define VGIC_ADDR_UNDEF		(-1)
> +#define IS_VGIC_ADDR_UNDEF(_x)  ((_x) == VGIC_ADDR_UNDEF)
> +
>  #define INTERRUPT_ID_BITS_SPIS	10
>  
>  #define vgic_irq_is_sgi(intid) ((intid) < VGIC_NR_SGIS)
> -- 
> 2.7.3
> 
Reviewed-by: Christoffer Dall <christoffer.dall at linaro.org>