[[RESEND] iommufd PATCH v2 1/2] i915/gvt: Move gvt mapping cache initialization to intel_vgpu_init_dev()

Yi Liu
2022-11-29T10:58:38Z

vfio container registers .dma_unmap() callback after the device is opened.
So it's fine for mdev drivers to initialize internal mapping cache in
.open_device(). See vfio_device_container_register().

Now with iommufd an access ops with an unmap callback is registered
when the device is bound to iommufd which is before .open_device()
is called. This implies gvt's .dma_unmap() could be called before its
internal mapping cache is initialized.

The fix is moving gvt mapping cache initialization to vGPU init. While
at it also move ptable initialization together.

Cc: Zhenyu Wang <zhenyuw@linux.intel.com>
Cc: Zhi Wang <zhi.a.wang@intel.com>
Cc: Kevin Tian <kevin.tian@intel.com>
Cc: intel-gvt-dev@lists.freedesktop.org
Reviewed-by: Zhi Wang <zhi.a.wang@intel.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
---
drivers/gpu/drm/i915/gvt/kvmgt.c | 13 +++++++++----
1 file changed, 9 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/i915/gvt/kvmgt.c b/drivers/gpu/drm/i915/gvt/kvmgt.c
index 7a45e5360caf..f563e5dbe66f 100644
--- a/drivers/gpu/drm/i915/gvt/kvmgt.c
+++ b/drivers/gpu/drm/i915/gvt/kvmgt.c
@@ -671,9 +671,6 @@ static int intel_vgpu_open_device(struct vfio_device *vfio_dev)

vgpu->attached = true;

- kvmgt_protect_table_init(vgpu);
- gvt_cache_init(vgpu);
-
vgpu->track_node.track_write = kvmgt_page_track_write;
vgpu->track_node.track_flush_slot = kvmgt_page_track_flush_slot;
kvm_page_track_register_notifier(vgpu->vfio_device.kvm,
@@ -1451,9 +1448,17 @@ static int intel_vgpu_init_dev(struct vfio_device *vfio_dev)
struct intel_vgpu *vgpu = vfio_dev_to_vgpu(vfio_dev);
struct intel_vgpu_type *type =
container_of(mdev->type, struct intel_vgpu_type, type);
+ int ret;

vgpu->gvt = kdev_to_i915(mdev->type->parent->dev)->gvt;
- return intel_gvt_create_vgpu(vgpu, type->conf);
+ ret = intel_gvt_create_vgpu(vgpu, type->conf);
+ if (ret)
+ return ret;
+
+ kvmgt_protect_table_init(vgpu);
+ gvt_cache_init(vgpu);
+
+ return 0;
}

static void intel_vgpu_release_dev(struct vfio_device *vfio_dev)
--
2.34.1