[RFC 7/9] KVM: KVM-VFIO: add new VFIO external API hooks

Eric Auger
2014-08-25T13:29:43Z

add functions that implement the gateway to the extended
external VFIO API:
- kvm_vfio_device_get_external_user
- kvm_vfio_device_put_external_user
- kvm_vfio_external_get_type
- kvm_vfio_external_get_base_device

Signed-off-by: Eric Auger <eric.auger@linaro.org>
---
arch/arm/include/asm/kvm_host.h | 6 ++++
virt/kvm/vfio.c | 62 +++++++++++++++++++++++++++++++++++++++++
2 files changed, 68 insertions(+)

diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h
index 6dfb404..62cbf5b 100644
--- a/arch/arm/include/asm/kvm_host.h
+++ b/arch/arm/include/asm/kvm_host.h
@@ -171,6 +171,12 @@ void kvm_set_spte_hva(struct kvm *kvm, unsigned long hva, pte_t pte);
unsigned long kvm_arm_num_regs(struct kvm_vcpu *vcpu);
int kvm_arm_copy_reg_indices(struct kvm_vcpu *vcpu, u64 __user *indices);

+struct vfio_device;
+struct vfio_device *kvm_vfio_device_get_external_user(struct file *filep);
+void kvm_vfio_device_put_external_user(struct vfio_device *vdev);
+int kvm_vfio_external_get_type(struct vfio_device *vdev);
+struct device *kvm_vfio_external_get_base_device(struct vfio_device *vdev);
+
/* We do not have shadow page tables, hence the empty hooks */
static inline int kvm_age_hva(struct kvm *kvm, unsigned long hva)
{
diff --git a/virt/kvm/vfio.c b/virt/kvm/vfio.c
index 89d3b75..f1c4e35 100644
--- a/virt/kvm/vfio.c
+++ b/virt/kvm/vfio.c
@@ -59,6 +59,67 @@ static void kvm_vfio_group_put_external_user(struct vfio_group *vfio_group)
symbol_put(vfio_group_put_external_user);
}

+struct vfio_device *kvm_vfio_device_get_external_user(struct file *filep)
+{
+ struct vfio_device *vdev;
+ struct vfio_device *(*fn)(struct file *);
+
+ fn = symbol_get(vfio_device_get_external_user);
+ if (!fn)
+ return ERR_PTR(-EINVAL);
+
+ vdev = fn(filep);
+
+ symbol_put(vfio_device_get_external_user);
+
+ return vdev;
+}
+
+void kvm_vfio_device_put_external_user(struct vfio_device *vdev)
+{
+ void (*fn)(struct vfio_device *);
+
+ fn = symbol_get(vfio_device_put_external_user);
+ if (!fn)
+ return;
+
+ fn(vdev);
+
+ symbol_put(vfio_device_put_external_user);
+}
+
+int kvm_vfio_external_get_type(struct vfio_device *vdev)
+{
+ int (*fn)(struct vfio_device *);
+ int ret;
+
+ fn = symbol_get(vfio_external_get_type);
+ if (!fn)
+ return -EINVAL;
+
+ ret = fn(vdev);
+
+ symbol_put(vfio_external_get_type);
+
+ return ret;
+}
+
+struct device *kvm_vfio_external_get_base_device(struct vfio_device *vdev)
+{
+ struct device *(*fn)(struct vfio_device *);
+ struct device *dev;
+
+ fn = symbol_get(vfio_external_get_base_device);
+ if (!fn)
+ return NULL;
+
+ dev = fn(vdev);
+
+ symbol_put(vfio_external_get_base_device);
+
+ return dev;
+}
+
static bool kvm_vfio_group_is_coherent(struct vfio_group *vfio_group)
{
long (*fn)(struct vfio_group *, unsigned long);
@@ -277,6 +338,7 @@ static int kvm_vfio_create(struct kvm_device *dev, u32 type)
return 0;
}

+
struct kvm_device_ops kvm_vfio_ops = {
.name = "kvm-vfio",
.create = kvm_vfio_create,
--
1.9.1