Re: [PATCH 02/26] vfio: Move KVM get/put helpers to colocate it with other KVM related code

Alex Williamson
2023-09-28T22:23:54Z

On Fri, 15 Sep 2023 17:30:54 -0700
Sean Christopherson <seanjc@google.com> wrote:

> Move the definitions of vfio_device_get_kvm_safe() and vfio_device_put_kvm()
> down in vfio_main.c to colocate them with other KVM-specific functions,
> e.g. to allow wrapping them all with a single CONFIG_KVM check.
>
> Signed-off-by: Sean Christopherson <seanjc@google.com>
> ---
> drivers/vfio/vfio_main.c | 104 +++++++++++++++++++--------------------
> 1 file changed, 52 insertions(+), 52 deletions(-)

Reviewed-by: Alex Williamson <alex.williamson@redhat.com>

> diff --git a/drivers/vfio/vfio_main.c b/drivers/vfio/vfio_main.c
> index 80e39f7a6d8f..6368eed7b7b2 100644
> --- a/drivers/vfio/vfio_main.c
> +++ b/drivers/vfio/vfio_main.c
> @@ -381,58 +381,6 @@ void vfio_unregister_group_dev(struct vfio_device *device)
> }
> EXPORT_SYMBOL_GPL(vfio_unregister_group_dev);
>
> -#if IS_ENABLED(CONFIG_KVM)
> -void vfio_device_get_kvm_safe(struct vfio_device *device, struct kvm *kvm)
> -{
> - void (*pfn)(struct kvm *kvm);
> - bool (*fn)(struct kvm *kvm);
> - bool ret;
> -
> - lockdep_assert_held(&device->dev_set->lock);
> -
> - if (!kvm)
> - return;
> -
> - pfn = symbol_get(kvm_put_kvm);
> - if (WARN_ON(!pfn))
> - return;
> -
> - fn = symbol_get(kvm_get_kvm_safe);
> - if (WARN_ON(!fn)) {
> - symbol_put(kvm_put_kvm);
> - return;
> - }
> -
> - ret = fn(kvm);
> - symbol_put(kvm_get_kvm_safe);
> - if (!ret) {
> - symbol_put(kvm_put_kvm);
> - return;
> - }
> -
> - device->put_kvm = pfn;
> - device->kvm = kvm;
> -}
> -
> -void vfio_device_put_kvm(struct vfio_device *device)
> -{
> - lockdep_assert_held(&device->dev_set->lock);
> -
> - if (!device->kvm)
> - return;
> -
> - if (WARN_ON(!device->put_kvm))
> - goto clear;
> -
> - device->put_kvm(device->kvm);
> - device->put_kvm = NULL;
> - symbol_put(kvm_put_kvm);
> -
> -clear:
> - device->kvm = NULL;
> -}
> -#endif
> -
> /* true if the vfio_device has open_device() called but not close_device() */
> static bool vfio_assert_device_open(struct vfio_device *device)
> {
> @@ -1354,6 +1302,58 @@ bool vfio_file_enforced_coherent(struct file *file)
> }
> EXPORT_SYMBOL_GPL(vfio_file_enforced_coherent);
>
> +#if IS_ENABLED(CONFIG_KVM)
> +void vfio_device_get_kvm_safe(struct vfio_device *device, struct kvm *kvm)
> +{
> + void (*pfn)(struct kvm *kvm);
> + bool (*fn)(struct kvm *kvm);
> + bool ret;
> +
> + lockdep_assert_held(&device->dev_set->lock);
> +
> + if (!kvm)
> + return;
> +
> + pfn = symbol_get(kvm_put_kvm);
> + if (WARN_ON(!pfn))
> + return;
> +
> + fn = symbol_get(kvm_get_kvm_safe);
> + if (WARN_ON(!fn)) {
> + symbol_put(kvm_put_kvm);
> + return;
> + }
> +
> + ret = fn(kvm);
> + symbol_put(kvm_get_kvm_safe);
> + if (!ret) {
> + symbol_put(kvm_put_kvm);
> + return;
> + }
> +
> + device->put_kvm = pfn;
> + device->kvm = kvm;
> +}
> +
> +void vfio_device_put_kvm(struct vfio_device *device)
> +{
> + lockdep_assert_held(&device->dev_set->lock);
> +
> + if (!device->kvm)
> + return;
> +
> + if (WARN_ON(!device->put_kvm))
> + goto clear;
> +
> + device->put_kvm(device->kvm);
> + device->put_kvm = NULL;
> + symbol_put(kvm_put_kvm);
> +
> +clear:
> + device->kvm = NULL;
> +}
> +#endif
> +
> static void vfio_device_file_set_kvm(struct file *file, struct kvm *kvm)
> {
> struct vfio_device_file *df = file->private_data;