From: Alexander Graf Date: Tue, 31 Aug 2010 02:25:39 +0000 (+0200) Subject: KVM: PPC: Add documentation for magic page enhancements X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=d1e87c7ee65a20b10faf7e59dbe2cc934c32473b;p=GitHub%2Fmt8127%2Fandroid_kernel_alcatel_ttab.git KVM: PPC: Add documentation for magic page enhancements This documents how to detect additional features inside the magic page when a guest maps it. Signed-off-by: Alexander Graf --- diff --git a/Documentation/kvm/ppc-pv.txt b/Documentation/kvm/ppc-pv.txt index 922cf954bd99..a7f2244b3be9 100644 --- a/Documentation/kvm/ppc-pv.txt +++ b/Documentation/kvm/ppc-pv.txt @@ -102,6 +102,20 @@ struct kvm_vcpu_arch_shared { Additions to the page must only occur at the end. Struct fields are always 32 or 64 bit aligned, depending on them being 32 or 64 bit wide respectively. +Magic page features +=================== + +When mapping the magic page using the KVM hypercall KVM_HC_PPC_MAP_MAGIC_PAGE, +a second return value is passed to the guest. This second return value contains +a bitmap of available features inside the magic page. + +The following enhancements to the magic page are currently available: + + KVM_MAGIC_FEAT_SR Maps SR registers r/w in the magic page + +For enhanced features in the magic page, please check for the existence of the +feature before using them! + MSR bits ========