kvm: make KVM_CAP_ENABLE_CAP_VM architecture agnostic

The first such capability to be handled in virt/kvm/ will be manual
dirty page reprotection.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Documentation/virtual/kvm/api.txt

@@ -1129,10 +1129,15 @@ documentation when it pops into existence).
 
 4.37 KVM_ENABLE_CAP
 
-Capability: KVM_CAP_ENABLE_CAP, KVM_CAP_ENABLE_CAP_VM
-Architectures: x86 (only KVM_CAP_ENABLE_CAP_VM),
-	       mips (only KVM_CAP_ENABLE_CAP), ppc, s390
-Type: vcpu ioctl, vm ioctl (with KVM_CAP_ENABLE_CAP_VM)
+Capability: KVM_CAP_ENABLE_CAP
+Architectures: mips, ppc, s390
+Type: vcpu ioctl
+Parameters: struct kvm_enable_cap (in)
+Returns: 0 on success; -1 on error
+
+Capability: KVM_CAP_ENABLE_CAP_VM
+Architectures: all
+Type: vcpu ioctl
 Parameters: struct kvm_enable_cap (in)
 Returns: 0 on success; -1 on error
 

arch/powerpc/kvm/powerpc.c

@@ -518,7 +518,6 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
 	case KVM_CAP_PPC_UNSET_IRQ:
 	case KVM_CAP_PPC_IRQ_LEVEL:
 	case KVM_CAP_ENABLE_CAP:
-	case KVM_CAP_ENABLE_CAP_VM:
 	case KVM_CAP_ONE_REG:
 	case KVM_CAP_IOEVENTFD:
 	case KVM_CAP_DEVICE_CTRL:
@@ -2084,8 +2083,8 @@ int kvm_vm_ioctl_irq_line(struct kvm *kvm, struct kvm_irq_level *irq_event,
 }
 
 
-static int kvm_vm_ioctl_enable_cap(struct kvm *kvm,
-				   struct kvm_enable_cap *cap)
+int kvm_vm_ioctl_enable_cap(struct kvm *kvm,
+			    struct kvm_enable_cap *cap)
 {
 	int r;
 
@@ -2273,15 +2272,6 @@ long kvm_arch_vm_ioctl(struct file *filp,
 
 		break;
 	}
-	case KVM_ENABLE_CAP:
-	{
-		struct kvm_enable_cap cap;
-		r = -EFAULT;
-		if (copy_from_user(&cap, argp, sizeof(cap)))
-			goto out;
-		r = kvm_vm_ioctl_enable_cap(kvm, &cap);
-		break;
-	}
 #ifdef CONFIG_SPAPR_TCE_IOMMU
 	case KVM_CREATE_SPAPR_TCE_64: {
 		struct kvm_create_spapr_tce_64 create_tce_64;

arch/s390/kvm/kvm-s390.c

@@ -464,7 +464,6 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
 	case KVM_CAP_S390_CSS_SUPPORT:
 	case KVM_CAP_IOEVENTFD:
 	case KVM_CAP_DEVICE_CTRL:
-	case KVM_CAP_ENABLE_CAP_VM:
 	case KVM_CAP_S390_IRQCHIP:
 	case KVM_CAP_VM_ATTRIBUTES:
 	case KVM_CAP_MP_STATE:
@@ -607,7 +606,7 @@ static void icpt_operexc_on_all_vcpus(struct kvm *kvm)
 	}
 }
 
-static int kvm_vm_ioctl_enable_cap(struct kvm *kvm, struct kvm_enable_cap *cap)
+int kvm_vm_ioctl_enable_cap(struct kvm *kvm, struct kvm_enable_cap *cap)
 {
 	int r;
 
@@ -1933,14 +1932,6 @@ long kvm_arch_vm_ioctl(struct file *filp,
 		r = kvm_s390_inject_vm(kvm, &s390int);
 		break;
 	}
-	case KVM_ENABLE_CAP: {
-		struct kvm_enable_cap cap;
-		r = -EFAULT;
-		if (copy_from_user(&cap, argp, sizeof(cap)))
-			break;
-		r = kvm_vm_ioctl_enable_cap(kvm, &cap);
-		break;
-	}
 	case KVM_CREATE_IRQCHIP: {
 		struct kvm_irq_routing_entry routing;
 

arch/x86/kvm/x86.c

@@ -3008,7 +3008,6 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
 	case KVM_CAP_HYPERV_TIME:
 	case KVM_CAP_IOAPIC_POLARITY_IGNORED:
 	case KVM_CAP_TSC_DEADLINE_TIMER:
-	case KVM_CAP_ENABLE_CAP_VM:
 	case KVM_CAP_DISABLE_QUIRKS:
 	case KVM_CAP_SET_BOOT_CPU_ID:
  	case KVM_CAP_SPLIT_IRQCHIP:
@@ -4431,8 +4430,8 @@ int kvm_vm_ioctl_irq_line(struct kvm *kvm, struct kvm_irq_level *irq_event,
 	return 0;
 }
 
-static int kvm_vm_ioctl_enable_cap(struct kvm *kvm,
-				   struct kvm_enable_cap *cap)
+int kvm_vm_ioctl_enable_cap(struct kvm *kvm,
+			    struct kvm_enable_cap *cap)
 {
 	int r;
 
@@ -4765,15 +4764,6 @@ long kvm_arch_vm_ioctl(struct file *filp,
 		r = 0;
 		break;
 	}
-	case KVM_ENABLE_CAP: {
-		struct kvm_enable_cap cap;
-
-		r = -EFAULT;
-		if (copy_from_user(&cap, argp, sizeof(cap)))
-			goto out;
-		r = kvm_vm_ioctl_enable_cap(kvm, &cap);
-		break;
-	}
 	case KVM_MEMORY_ENCRYPT_OP: {
 		r = -ENOTTY;
 		if (kvm_x86_ops->mem_enc_op)

include/linux/kvm_host.h

@@ -765,6 +765,8 @@ int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm,
 
 int kvm_vm_ioctl_irq_line(struct kvm *kvm, struct kvm_irq_level *irq_level,
 			bool line_status);
+int kvm_vm_ioctl_enable_cap(struct kvm *kvm,
+			    struct kvm_enable_cap *cap);
 long kvm_arch_vm_ioctl(struct file *filp,
 		       unsigned int ioctl, unsigned long arg);
 

virt/kvm/kvm_main.c

@@ -2948,6 +2948,7 @@ static long kvm_vm_ioctl_check_extension_generic(struct kvm *kvm, long arg)
 #endif
 	case KVM_CAP_IOEVENTFD_ANY_LENGTH:
 	case KVM_CAP_CHECK_EXTENSION_VM:
+	case KVM_CAP_ENABLE_CAP_VM:
 		return 1;
 #ifdef CONFIG_KVM_MMIO
 	case KVM_CAP_COALESCED_MMIO:
@@ -2971,6 +2972,21 @@ static long kvm_vm_ioctl_check_extension_generic(struct kvm *kvm, long arg)
 	return kvm_vm_ioctl_check_extension(kvm, arg);
 }
 
+int __attribute__((weak)) kvm_vm_ioctl_enable_cap(struct kvm *kvm,
+						  struct kvm_enable_cap *cap)
+{
+	return -EINVAL;
+}
+
+static int kvm_vm_ioctl_enable_cap_generic(struct kvm *kvm,
+					   struct kvm_enable_cap *cap)
+{
+	switch (cap->cap) {
+	default:
+		return kvm_vm_ioctl_enable_cap(kvm, cap);
+	}
+}
+
 static long kvm_vm_ioctl(struct file *filp,
 			   unsigned int ioctl, unsigned long arg)
 {
@@ -2984,6 +3000,15 @@ static long kvm_vm_ioctl(struct file *filp,
 	case KVM_CREATE_VCPU:
 		r = kvm_vm_ioctl_create_vcpu(kvm, arg);
 		break;
+	case KVM_ENABLE_CAP: {
+		struct kvm_enable_cap cap;
+
+		r = -EFAULT;
+		if (copy_from_user(&cap, argp, sizeof(cap)))
+			goto out;
+		r = kvm_vm_ioctl_enable_cap_generic(kvm, &cap);
+		break;
+	}
 	case KVM_SET_USER_MEMORY_REGION: {
 		struct kvm_userspace_memory_region kvm_userspace_mem;