KVM: PPC: Magic Page Book3s support

We need to override EA as well as PA lookups for the magic page. When the guest
tells us to project it, the magic page overrides any guest mappings.

In order to reflect that, we need to hook into all the MMU layers of KVM to
force map the magic page if necessary.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>

1 files changed, 16 insertions, 0 deletions

diff --git a/arch/powerpc/kvm/book3s_32_mmu.c b/arch/powerpc/kvm/book3s_32_mmu.c
index 449bce5f021a..a7d121adc842 100644
--- a/arch/powerpc/kvm/book3s_32_mmu.c
+++ b/arch/powerpc/kvm/book3s_32_mmu.c
@@ -281,8 +281,24 @@ static int kvmppc_mmu_book3s_32_xlate(struct kvm_vcpu *vcpu, gva_t eaddr,
                                       struct kvmppc_pte *pte, bool data)
 {
         int r;
+        ulong mp_ea = vcpu->arch.magic_page_ea;
 
         pte->eaddr = eaddr;
+
+        /* Magic page override */
+        if (unlikely(mp_ea) &&
+            unlikely((eaddr & ~0xfffULL) == (mp_ea & ~0xfffULL)) &&
+            !(vcpu->arch.shared->msr & MSR_PR)) {
+                pte->vpage = kvmppc_mmu_book3s_32_ea_to_vp(vcpu, eaddr, data);
+                pte->raddr = vcpu->arch.magic_page_pa | (pte->raddr & 0xfff);
+                pte->raddr &= KVM_PAM;
+                pte->may_execute = true;
+                pte->may_read = true;
+                pte->may_write = true;
+
+                return 0;
+        }
+
         r = kvmppc_mmu_book3s_32_xlate_bat(vcpu, eaddr, pte, data);
         if (r < 0)
                r = kvmppc_mmu_book3s_32_xlate_pte(vcpu, eaddr, pte, data, true);