KVM: PPC: Book3S PR: Don't include SPAPR TCE code on non-pseries plat…

…forms

Commit e91aa8e ("KVM: PPC: Enable IOMMU_API for KVM_BOOK3S_64
permanently", 2017-03-22) enabled the SPAPR TCE code for all 64-bit
Book 3S kernel configurations in order to simplify the code and
reduce #ifdefs.  However, 64-bit Book 3S PPC platforms other than
pseries and powernv don't implement the necessary IOMMU callbacks,
leading to build failures like the following (for a pasemi config):

scripts/kconfig/conf  --silentoldconfig Kconfig
warning: (KVM_BOOK3S_64) selects SPAPR_TCE_IOMMU which has unmet direct dependencies (IOMMU_SUPPORT && (PPC_POWERNV || PPC_PSERIES))

...

  CC [M]  arch/powerpc/kvm/book3s_64_vio.o
/home/paulus/kernel/kvm/arch/powerpc/kvm/book3s_64_vio.c: In function ‘kvmppc_clear_tce’:
/home/paulus/kernel/kvm/arch/powerpc/kvm/book3s_64_vio.c:363:2: error: implicit declaration of function ‘iommu_tce_xchg’ [-Werror=implicit-function-declaration]
  iommu_tce_xchg(tbl, entry, &hpa, &dir);
  ^

To fix this, we make the inclusion of the SPAPR TCE support, and the
code that uses it in book3s_vio.c and book3s_vio_hv.c, depend on
the inclusion of support for the pseries and/or powernv platforms.
This means that when running a 'pseries' guest on those platforms,
the guest won't have in-kernel acceleration of the PAPR TCE hypercalls,
but at least now they compile.

Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>

arch/powerpc/kvm/Kconfig

@@ -67,7 +67,7 @@ config KVM_BOOK3S_64
 	select KVM_BOOK3S_64_HANDLER
 	select KVM
 	select KVM_BOOK3S_PR_POSSIBLE if !KVM_BOOK3S_HV_POSSIBLE
-	select SPAPR_TCE_IOMMU if IOMMU_SUPPORT
+	select SPAPR_TCE_IOMMU if IOMMU_SUPPORT && (PPC_SERIES || PPC_POWERNV)
 	---help---
 	  Support running unmodified book3s_64 and book3s_32 guest kernels
 	  in virtual machines on book3s_64 host processors.

arch/powerpc/kvm/Makefile

@@ -46,7 +46,7 @@ kvm-e500mc-objs := \
 	e500_emulate.o
 kvm-objs-$(CONFIG_KVM_E500MC) := $(kvm-e500mc-objs)
 
-kvm-book3s_64-builtin-objs-$(CONFIG_KVM_BOOK3S_64_HANDLER) := \
+kvm-book3s_64-builtin-objs-$(CONFIG_SPAPR_TCE_IOMMU) := \
 	book3s_64_vio_hv.o
 
 kvm-pr-y := \
@@ -90,11 +90,11 @@ kvm-book3s_64-objs-$(CONFIG_KVM_XICS) += \
 	book3s_xics.o
 
 kvm-book3s_64-objs-$(CONFIG_KVM_XIVE) += book3s_xive.o
+kvm-book3s_64-objs-$(CONFIG_SPAPR_TCE_IOMMU) += book3s_64_vio.o
 
 kvm-book3s_64-module-objs := \
 	$(common-objs-y) \
 	book3s.o \
-	book3s_64_vio.o \
 	book3s_rtas.o \
 	$(kvm-book3s_64-objs-y)
 

arch/powerpc/kvm/book3s_pr_papr.c

@@ -262,36 +262,37 @@ static int kvmppc_h_pr_protect(struct kvm_vcpu *vcpu)
 	return EMULATE_DONE;
 }
 
-static int kvmppc_h_pr_put_tce(struct kvm_vcpu *vcpu)
+static int kvmppc_h_pr_logical_ci_load(struct kvm_vcpu *vcpu)
 {
-	unsigned long liobn = kvmppc_get_gpr(vcpu, 4);
-	unsigned long ioba = kvmppc_get_gpr(vcpu, 5);
-	unsigned long tce = kvmppc_get_gpr(vcpu, 6);
 	long rc;
 
-	rc = kvmppc_h_put_tce(vcpu, liobn, ioba, tce);
+	rc = kvmppc_h_logical_ci_load(vcpu);
 	if (rc == H_TOO_HARD)
 		return EMULATE_FAIL;
 	kvmppc_set_gpr(vcpu, 3, rc);
 	return EMULATE_DONE;
 }
 
-static int kvmppc_h_pr_logical_ci_load(struct kvm_vcpu *vcpu)
+static int kvmppc_h_pr_logical_ci_store(struct kvm_vcpu *vcpu)
 {
 	long rc;
 
-	rc = kvmppc_h_logical_ci_load(vcpu);
+	rc = kvmppc_h_logical_ci_store(vcpu);
 	if (rc == H_TOO_HARD)
 		return EMULATE_FAIL;
 	kvmppc_set_gpr(vcpu, 3, rc);
 	return EMULATE_DONE;
 }
 
-static int kvmppc_h_pr_logical_ci_store(struct kvm_vcpu *vcpu)
+#ifdef CONFIG_SPAPR_TCE_IOMMU
+static int kvmppc_h_pr_put_tce(struct kvm_vcpu *vcpu)
 {
+	unsigned long liobn = kvmppc_get_gpr(vcpu, 4);
+	unsigned long ioba = kvmppc_get_gpr(vcpu, 5);
+	unsigned long tce = kvmppc_get_gpr(vcpu, 6);
 	long rc;
 
-	rc = kvmppc_h_logical_ci_store(vcpu);
+	rc = kvmppc_h_put_tce(vcpu, liobn, ioba, tce);
 	if (rc == H_TOO_HARD)
 		return EMULATE_FAIL;
 	kvmppc_set_gpr(vcpu, 3, rc);
@@ -329,6 +330,23 @@ static int kvmppc_h_pr_stuff_tce(struct kvm_vcpu *vcpu)
 	return EMULATE_DONE;
 }
 
+#else /* CONFIG_SPAPR_TCE_IOMMU */
+static int kvmppc_h_pr_put_tce(struct kvm_vcpu *vcpu)
+{
+	return EMULATE_FAIL;
+}
+
+static int kvmppc_h_pr_put_tce_indirect(struct kvm_vcpu *vcpu)
+{
+	return EMULATE_FAIL;
+}
+
+static int kvmppc_h_pr_stuff_tce(struct kvm_vcpu *vcpu)
+{
+	return EMULATE_FAIL;
+}
+#endif /* CONFIG_SPAPR_TCE_IOMMU */
+
 static int kvmppc_h_pr_xics_hcall(struct kvm_vcpu *vcpu, u32 cmd)
 {
 	long rc = kvmppc_xics_hcall(vcpu, cmd);

arch/powerpc/kvm/powerpc.c

@@ -1749,7 +1749,7 @@ long kvm_arch_vm_ioctl(struct file *filp,
 		r = kvm_vm_ioctl_enable_cap(kvm, &cap);
 		break;
 	}
-#ifdef CONFIG_PPC_BOOK3S_64
+#ifdef CONFIG_SPAPR_TCE_IOMMU
 	case KVM_CREATE_SPAPR_TCE_64: {
 		struct kvm_create_spapr_tce_64 create_tce_64;
 
@@ -1780,6 +1780,8 @@ long kvm_arch_vm_ioctl(struct file *filp,
 		r = kvm_vm_ioctl_create_spapr_tce(kvm, &create_tce_64);
 		goto out;
 	}
+#endif
+#ifdef CONFIG_PPC_BOOK3S_64
 	case KVM_PPC_GET_SMMU_INFO: {
 		struct kvm_ppc_smmu_info info;
 		struct kvm *kvm = filp->private_data;