On Fri, Apr 13, 2018 at 10:20:48AM +0200, Eric Auger wrote: > We introduce a new KVM_VGIC_V3_ADDR_TYPE_REDIST_REGION attribute in > KVM_DEV_ARM_VGIC_GRP_ADDR group. It allows userspace to provide the > base address and size of a redistributor region > > Compared to KVM_VGIC_V3_ADDR_TYPE_REDIST, this new attribute allows > to declare several separate redistributor regions. > > So the whole redist space does not need to be contiguous anymore. > > Signed-off-by: Eric Auger <eric.auger@xxxxxxxxxx> > --- > Documentation/virtual/kvm/devices/arm-vgic-v3.txt | 25 ++++++++++++++++++++++- > 1 file changed, 24 insertions(+), 1 deletion(-) > > diff --git a/Documentation/virtual/kvm/devices/arm-vgic-v3.txt b/Documentation/virtual/kvm/devices/arm-vgic-v3.txt > index 9293b45..cbc4328 100644 > --- a/Documentation/virtual/kvm/devices/arm-vgic-v3.txt > +++ b/Documentation/virtual/kvm/devices/arm-vgic-v3.txt > @@ -27,9 +27,32 @@ Groups: > VCPU and all of the redistributor pages are contiguous. > Only valid for KVM_DEV_TYPE_ARM_VGIC_V3. > This address needs to be 64K aligned. > + > + KVM_VGIC_V3_ADDR_TYPE_REDIST_REGION (rw, 64-bit) > + The attr field of kvm_device_attr encodes 3 values: > + bits: | 63 .... 52 | 51 .... 16 | 15 - 12 |11 - 0 > + values: | count | base | flags | index > + - index encodes the unique redistributor region index I'm not entirely sure I understand the purpose of the index field. Isn't a redistributor region identified uniquely by its base address? Otherwise this looks good. Thanks, -Christoffer > + - flags: reserved for future use, currently 0 > + - base field encodes bits [51:16] of the guest physical base address > + of the first redistributor in the region. > + - count encodes the number of redistributors in the region. Must be > + greater than 0. > + There are two 64K pages for each redistributor in the region and > + redistributors are laid out contiguously within the region. Regions > + are filled with redistributors in the index order. The sum of all > + region count fields must be greater than or equal to the number of > + VCPUs. Redistributor regions must be registered in the incremental > + index order, starting from index 0. > + Only valid for KVM_DEV_TYPE_ARM_VGIC_V3. > + > + It is invalid to mix calls with KVM_VGIC_V3_ADDR_TYPE_REDIST and > + KVM_VGIC_V3_ADDR_TYPE_REDIST_REGION attributes. > + > Errors: > -E2BIG: Address outside of addressable IPA range > - -EINVAL: Incorrectly aligned address > + -EINVAL: Incorrectly aligned address, bad redistributor region > + count/index, mixed redistributor region attribute usage > -EEXIST: Address already configured > -ENXIO: The group or attribute is unknown/unsupported for this device > or hardware support is missing. > -- > 2.5.5 >