KVM: PPC: Allocate vcpu struct in common PPC code

Move allocation of all flavors of PPC vCPUs to common PPC code.  All
variants either allocate 'struct kvm_vcpu' directly, or require that
the embedded 'struct kvm_vcpu' member be located at offset 0, i.e.
guarantee that the allocation can be directly interpreted as a 'struct
kvm_vcpu' object.

Remove the message from the build-time assertion regarding placement of
the struct, as compatibility with the arch usercopy region is no longer
the sole dependent on 'struct kvm_vcpu' being at offset zero.

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

1 files changed, 18 insertions, 5 deletions

diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c
index 416fb3d2a1d0..fd978f681b66 100644
--- a/arch/powerpc/kvm/powerpc.c
+++ b/arch/powerpc/kvm/powerpc.c
@@ -723,12 +723,23 @@ void kvm_arch_flush_shadow_memslot(struct kvm *kvm,
 struct kvm_vcpu *kvm_arch_vcpu_create(struct kvm *kvm, unsigned int id)
 {
 	struct kvm_vcpu *vcpu;
-	vcpu = kvmppc_core_vcpu_create(kvm, id);
-	if (!IS_ERR(vcpu)) {
-		vcpu->arch.wqp = &vcpu->wq;
-		kvmppc_create_vcpu_debugfs(vcpu, id);
-	}
+	int err;
+
+	vcpu = kmem_cache_zalloc(kvm_vcpu_cache, GFP_KERNEL);
+	if (!vcpu)
+		return ERR_PTR(-ENOMEM);
+
+	err = kvmppc_core_vcpu_create(kvm, vcpu, id);
+	if (err)
+		goto free_vcpu;
+
+	vcpu->arch.wqp = &vcpu->wq;
+	kvmppc_create_vcpu_debugfs(vcpu, id);
 	return vcpu;
+
+free_vcpu:
+	kmem_cache_free(kvm_vcpu_cache, vcpu);
+	return ERR_PTR(err);
 }
 
 void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu)
@@ -758,6 +769,8 @@ void kvm_arch_vcpu_free(struct kvm_vcpu *vcpu)
 	}
 
 	kvmppc_core_vcpu_free(vcpu);
+
+	kmem_cache_free(kvm_vcpu_cache, vcpu);
 }
 
 void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)