kvm: Add support for arch compat vm ioctls

We will introduce the first architecture specific compat vm ioctl in the
next patch. Add all necessary boilerplate to allow architectures to
override compat vm ioctls when necessary.

Signed-off-by: Alexander Graf <graf@amazon.com>
Message-Id: <20221017184541.2658-2-graf@amazon.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index 32f259fa58013eca0af1ea419b6a6a21d88e8272..00c3448ba7f8b96fb4e8c643636c5d82f720412d 100644 (file)
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -1390,6 +1390,8 @@ 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);
+long kvm_arch_vm_compat_ioctl(struct file *filp, unsigned int ioctl,
+                             unsigned long arg);
 
 int kvm_arch_vcpu_ioctl_get_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu);
 int kvm_arch_vcpu_ioctl_set_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu);

diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index e30f1b4ecfa5d1c3110bdbd36108aa417de008a9..1376a47fedeedbd902db2f0b8ecfdd44cd87d9a0 100644 (file)
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -4839,6 +4839,12 @@ struct compat_kvm_clear_dirty_log {
        };
 };
 
+long __weak kvm_arch_vm_compat_ioctl(struct file *filp, unsigned int ioctl,
+                                    unsigned long arg)
+{
+       return -ENOTTY;
+}
+
 static long kvm_vm_compat_ioctl(struct file *filp,
                           unsigned int ioctl, unsigned long arg)
 {
@@ -4847,6 +4853,11 @@ static long kvm_vm_compat_ioctl(struct file *filp,
 
        if (kvm->mm != current->mm || kvm->vm_dead)
                return -EIO;
+
+       r = kvm_arch_vm_compat_ioctl(filp, ioctl, arg);
+       if (r != -ENOTTY)
+               return r;
+
        switch (ioctl) {
 #ifdef CONFIG_KVM_GENERIC_DIRTYLOG_READ_PROTECT
        case KVM_CLEAR_DIRTY_LOG: {