[PATCH v1] drm/virtio: Factor out common dmabuf unmapping code

From: Dmitry Osipenko
Date: Mon Dec 02 2024 - 00:41:06 EST


Move out dmabuf detachment and unmapping into separate function. This
removes duplicated code and there is no need to check the GEM's kref now,
since both bo->attached and bo->sgt are unset under held reservation lock.

Signed-off-by: Dmitry Osipenko <dmitry.osipenko@xxxxxxxxxxxxx>
---
drivers/gpu/drm/virtio/virtgpu_prime.c | 35 ++++++++++++++------------
1 file changed, 19 insertions(+), 16 deletions(-)

diff --git a/drivers/gpu/drm/virtio/virtgpu_prime.c b/drivers/gpu/drm/virtio/virtgpu_prime.c
index 33084ce1d01d..101d1a6517ae 100644
--- a/drivers/gpu/drm/virtio/virtgpu_prime.c
+++ b/drivers/gpu/drm/virtio/virtgpu_prime.c
@@ -184,22 +184,33 @@ int virtgpu_dma_buf_import_sgt(struct virtio_gpu_mem_entry **ents,
return 0;
}

-static void virtgpu_dma_buf_free_obj(struct drm_gem_object *obj)
+static void virtgpu_dma_buf_unmap(struct virtio_gpu_object *bo)
{
- struct virtio_gpu_object *bo = gem_to_virtio_gpu_obj(obj);
- struct virtio_gpu_device *vgdev = obj->dev->dev_private;
- struct dma_buf_attachment *attach = obj->import_attach;
- struct dma_resv *resv = attach->dmabuf->resv;
+ struct dma_buf_attachment *attach = bo->base.base.import_attach;

- if (attach) {
- dma_resv_lock(resv, NULL);
+ dma_resv_assert_held(attach->dmabuf->resv);

+ if (bo->created) {
virtio_gpu_detach_object_fenced(bo);

if (bo->sgt)
dma_buf_unmap_attachment(attach, bo->sgt,
DMA_BIDIRECTIONAL);

+ bo->sgt = NULL;
+ }
+}
+
+static void virtgpu_dma_buf_free_obj(struct drm_gem_object *obj)
+{
+ struct virtio_gpu_object *bo = gem_to_virtio_gpu_obj(obj);
+ struct virtio_gpu_device *vgdev = obj->dev->dev_private;
+ struct dma_buf_attachment *attach = obj->import_attach;
+ struct dma_resv *resv = attach->dmabuf->resv;
+
+ if (attach) {
+ dma_resv_lock(resv, NULL);
+ virtgpu_dma_buf_unmap(bo);
dma_resv_unlock(resv);

dma_buf_detach(attach->dmabuf, attach);
@@ -272,15 +283,7 @@ static void virtgpu_dma_buf_move_notify(struct dma_buf_attachment *attach)
struct drm_gem_object *obj = attach->importer_priv;
struct virtio_gpu_object *bo = gem_to_virtio_gpu_obj(obj);

- if (bo->created && kref_read(&obj->refcount)) {
- virtio_gpu_detach_object_fenced(bo);
-
- if (bo->sgt)
- dma_buf_unmap_attachment(attach, bo->sgt,
- DMA_BIDIRECTIONAL);
-
- bo->sgt = NULL;
- }
+ virtgpu_dma_buf_unmap(bo);
}

static const struct dma_buf_attach_ops virtgpu_dma_buf_attach_ops = {
--
2.47.0