KVM: Add per-vm capability enablement.

Allow KVM_ENABLE_CAP to act on a vm as well as on a vcpu. This makes more
sense when the caller wants to enable a vm-related capability.

s390 will be the first user; wire it up.

Reviewed-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>

1 files changed, 24 insertions, 0 deletions

diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 7337c577e949..9f1e99f12d4f 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -159,6 +159,7 @@ int kvm_dev_ioctl_check_extension(long ext)
         case KVM_CAP_S390_CSS_SUPPORT:
         case KVM_CAP_IOEVENTFD:
         case KVM_CAP_DEVICE_CTRL:
+        case KVM_CAP_ENABLE_CAP_VM:
                 r = 1;
                 break;
         case KVM_CAP_NR_VCPUS:
@@ -187,6 +188,21 @@ int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm,
         return 0;
 }
 
+static int kvm_vm_ioctl_enable_cap(struct kvm *kvm, struct kvm_enable_cap *cap)
+{
+        int r;
+
+        if (cap->flags)
+                return -EINVAL;
+
+        switch (cap->cap) {
+        default:
+                r = -EINVAL;
+                break;
+        }
+        return r;
+}
+
 long kvm_arch_vm_ioctl(struct file *filp,
                        unsigned int ioctl, unsigned long arg)
 {
@@ -204,6 +220,14 @@ 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;
+        }
         default:
                 r = -ENOTTY;
         }