From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752586AbeDIVi4 (ORCPT ); Mon, 9 Apr 2018 17:38:56 -0400 Received: from mail-wm0-f65.google.com ([74.125.82.65]:38586 "EHLO mail-wm0-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751662AbeDIViy (ORCPT ); Mon, 9 Apr 2018 17:38:54 -0400 X-Google-Smtp-Source: AIpwx499378tX3/Zab/xjzRWhWDj/lT9awIdIar/CFiYi/fTXcWiNn/QSN4UiIVc1EZ6ryjIKO2yTA== Date: Mon, 9 Apr 2018 23:38:52 +0200 From: Christoffer Dall To: Eric Auger Cc: eric.auger.pro@gmail.com, linux-kernel@vger.kernel.org, kvm@vger.kernel.org, kvmarm@lists.cs.columbia.edu, marc.zyngier@arm.com, peter.maydell@linaro.org, andre.przywara@arm.com, drjones@redhat.com, wei@redhat.com Subject: Re: [RFC v2 02/12] KVM: arm/arm64: Document KVM_VGIC_V3_ADDR_TYPE_REDIST_REGION Message-ID: <20180409213852.GJ10904@cbox> References: <1522159456-10419-1-git-send-email-eric.auger@redhat.com> <1522159456-10419-3-git-send-email-eric.auger@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1522159456-10419-3-git-send-email-eric.auger@redhat.com> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Eric, On Tue, Mar 27, 2018 at 04:04:06PM +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 > --- > Documentation/virtual/kvm/devices/arm-vgic-v3.txt | 18 ++++++++++++++++++ > 1 file changed, 18 insertions(+) > > diff --git a/Documentation/virtual/kvm/devices/arm-vgic-v3.txt b/Documentation/virtual/kvm/devices/arm-vgic-v3.txt > index 9293b45..0ded904 100644 > --- a/Documentation/virtual/kvm/devices/arm-vgic-v3.txt > +++ b/Documentation/virtual/kvm/devices/arm-vgic-v3.txt > @@ -27,6 +27,24 @@ 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 > + - 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. There are two 64K pages > + for each VCPU and all of the redistributor pages are contiguous should this be two 64K pages for the number of redistributors in this region as specified by count ? > + within the redistributor region. > + - count encodes the number of redistributors in the region. I assume it's implied that the user must register a total number of redistributors across all the regions that matches the number of vcpus, and that otherwise something bad happens? > + 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. When attempted an > + -EINVAL error is returned. > + > Errors: > -E2BIG: Address outside of addressable IPA range > -EINVAL: Incorrectly aligned address > -- > 2.5.5 > Thanks, -Christoffer