KVM: PPC: Add support for explicit HIOR setting

Until now, we always set HIOR based on the PVR, but this is just wrong.
Instead, we should be setting HIOR explicitly, so user space can decide
what the initial HIOR value is - just like on real hardware.

We keep the old PVR based way around for backwards compatibility, but
once user space uses the SET_ONE_REG based method, we drop the PVR logic.

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

4 files changed, 21 insertions, 2 deletions

diff --git a/arch/powerpc/include/asm/kvm.h b/arch/powerpc/include/asm/kvm.h
index 663c57f87165..f41adcda1468 100644
--- a/arch/powerpc/include/asm/kvm.h
+++ b/arch/powerpc/include/asm/kvm.h
@@ -331,4 +331,6 @@ struct kvm_book3e_206_tlb_params {
         __u32 reserved[8];
 };
 
+#define KVM_REG_PPC_HIOR        (KVM_REG_PPC | KVM_REG_SIZE_U64 | 0x1)
+
 #endif /* __LINUX_KVM_POWERPC_H */
diff --git a/arch/powerpc/include/asm/kvm_book3s.h b/arch/powerpc/include/asm/kvm_book3s.h
index 3c3edee672aa..aa795ccef294 100644
--- a/arch/powerpc/include/asm/kvm_book3s.h
+++ b/arch/powerpc/include/asm/kvm_book3s.h
@@ -90,6 +90,8 @@ struct kvmppc_vcpu_book3s {
 #endif
         int context_id[SID_CONTEXTS];
 
+        bool hior_explicit;             /* HIOR is set by ioctl, not PVR */
+
         struct hlist_head hpte_hash_pte[HPTEG_HASH_NUM_PTE];
         struct hlist_head hpte_hash_pte_long[HPTEG_HASH_NUM_PTE_LONG];
         struct hlist_head hpte_hash_vpte[HPTEG_HASH_NUM_VPTE];
diff --git a/arch/powerpc/kvm/book3s_pr.c b/arch/powerpc/kvm/book3s_pr.c
index c193625d5289..00efda6dc0e2 100644
--- a/arch/powerpc/kvm/book3s_pr.c
+++ b/arch/powerpc/kvm/book3s_pr.c
@@ -157,14 +157,16 @@ void kvmppc_set_pvr(struct kvm_vcpu *vcpu, u32 pvr)
 #ifdef CONFIG_PPC_BOOK3S_64
         if ((pvr >= 0x330000) && (pvr < 0x70330000)) {
                 kvmppc_mmu_book3s_64_init(vcpu);
-                to_book3s(vcpu)->hior = 0xfff00000;
+                if (!to_book3s(vcpu)->hior_explicit)
+                        to_book3s(vcpu)->hior = 0xfff00000;
                 to_book3s(vcpu)->msr_mask = 0xffffffffffffffffULL;
                 vcpu->arch.cpu_type = KVM_CPU_3S_64;
         } else
 #endif
         {
                 kvmppc_mmu_book3s_32_init(vcpu);
-                to_book3s(vcpu)->hior = 0;
+                if (!to_book3s(vcpu)->hior_explicit)
+                        to_book3s(vcpu)->hior = 0;
                 to_book3s(vcpu)->msr_mask = 0xffffffffULL;
                 vcpu->arch.cpu_type = KVM_CPU_3S_32;
         }
diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c
index 089c61bf0e16..59852091b389 100644
--- a/arch/powerpc/kvm/powerpc.c
+++ b/arch/powerpc/kvm/powerpc.c
@@ -212,6 +212,7 @@ int kvm_dev_ioctl_check_extension(long ext)
         case KVM_CAP_PPC_BOOKE_SREGS:
 #else
         case KVM_CAP_PPC_SEGSTATE:
+        case KVM_CAP_PPC_HIOR:
         case KVM_CAP_PPC_PAPR:
 #endif
         case KVM_CAP_PPC_UNSET_IRQ:
@@ -652,6 +653,11 @@ static int kvm_vcpu_ioctl_get_one_reg(struct kvm_vcpu *vcpu,
         int r = -EINVAL;
 
         switch (reg->id) {
+#ifdef CONFIG_PPC_BOOK3S
+        case KVM_REG_PPC_HIOR:
+                r = put_user(to_book3s(vcpu)->hior, (u64 __user *)reg->addr);
+                break;
+#endif
         default:
                 break;
         }
@@ -665,6 +671,13 @@ static int kvm_vcpu_ioctl_set_one_reg(struct kvm_vcpu *vcpu,
         int r = -EINVAL;
 
         switch (reg->id) {
+#ifdef CONFIG_PPC_BOOK3S
+        case KVM_ONE_REG_PPC_HIOR:
+                r = get_user(to_book3s(vcpu)->hior, (u64 __user *)reg->addr);
+                if (!r)
+                        to_book3s(vcpu)->hior_explicit = true;
+                break;
+#endif
         default:
                 break;
         }