[PATCH 0/2] drm/tegra: Avoid using import_attach directly

[PATCH 0/2] drm/tegra: Avoid using import_attach directly

[Thomas Zimmermann]

The field import_attach of struct drm_gem_object is often only
required by PRIME code. In other places, replace its use with
clearer alternatives.

Thomas Zimmermann (2):
  drm/tegra: Test for imported buffers with drm_gem_is_imported()
  drm/tegra: Use dma_buf from GEM object instance

 drivers/gpu/drm/tegra/gem.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

-- 
2.49.0

[PATCH 1/2] drm/tegra: Test for imported buffers with drm_gem_is_imported()

[Thomas Zimmermann]

Instead of testing import_attach for imported GEM buffers, invoke
drm_gem_is_imported() to do the test.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
---
 drivers/gpu/drm/tegra/gem.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/tegra/gem.c b/drivers/gpu/drm/tegra/gem.c
index dbc1394f96b8..8ede07fb7a21 100644
--- a/drivers/gpu/drm/tegra/gem.c
+++ b/drivers/gpu/drm/tegra/gem.c
@@ -523,7 +523,7 @@ void tegra_bo_free_object(struct drm_gem_object *gem)
 	if (tegra->domain) {
 		tegra_bo_iommu_unmap(tegra, bo);
 
-		if (gem->import_attach) {
+		if (drm_gem_is_imported(gem)) {
 			dma_buf_unmap_attachment_unlocked(gem->import_attach, bo->sgt,
 							  DMA_TO_DEVICE);
 			dma_buf_detach(gem->import_attach->dmabuf, gem->import_attach);
-- 
2.49.0

[PATCH 2/2] drm/tegra: Use dma_buf from GEM object instance

[Thomas Zimmermann]

Avoid dereferencing struct drm_gem_object.import_attach for the
imported dma-buf. The dma_buf field in the GEM object instance refers
to the same buffer. Prepares to make import_attach an implementation
detail of PRIME.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
---
 drivers/gpu/drm/tegra/gem.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/tegra/gem.c b/drivers/gpu/drm/tegra/gem.c
index 8ede07fb7a21..41a285ec889f 100644
--- a/drivers/gpu/drm/tegra/gem.c
+++ b/drivers/gpu/drm/tegra/gem.c
@@ -526,7 +526,7 @@ void tegra_bo_free_object(struct drm_gem_object *gem)
 		if (drm_gem_is_imported(gem)) {
 			dma_buf_unmap_attachment_unlocked(gem->import_attach, bo->sgt,
 							  DMA_TO_DEVICE);
-			dma_buf_detach(gem->import_attach->dmabuf, gem->import_attach);
+			dma_buf_detach(gem->dma_buf, gem->import_attach);
 		}
 	}
 
-- 
2.49.0

Re: [PATCH 0/2] drm/tegra: Avoid using import_attach directly

[Christian König]

Reviewed-by: Christian König <christian.koenig@amd.com> for both patches.

On 19.06.25 13:26, Thomas Zimmermann wrote:
> The field import_attach of struct drm_gem_object is often only
> required by PRIME code. In other places, replace its use with
> clearer alternatives.
> 
> Thomas Zimmermann (2):
>   drm/tegra: Test for imported buffers with drm_gem_is_imported()
>   drm/tegra: Use dma_buf from GEM object instance
> 
>  drivers/gpu/drm/tegra/gem.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 

Re: [PATCH 0/2] drm/tegra: Avoid using import_attach directly

[Thierry Reding]

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On Thu, Jun 19, 2025 at 01:26:59PM +0200, Thomas Zimmermann wrote:
> The field import_attach of struct drm_gem_object is often only
> required by PRIME code. In other places, replace its use with
> clearer alternatives.
> 
> Thomas Zimmermann (2):
>   drm/tegra: Test for imported buffers with drm_gem_is_imported()
>   drm/tegra: Use dma_buf from GEM object instance
> 
>  drivers/gpu/drm/tegra/gem.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)

Applied, thanks.

Thierry

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[PATCH 0/2] drm/tegra: Avoid struct drm_gem_object.import_attach

[Thomas Zimmermann]

Avoid the use of struct drm_gem_object.import_attach to get the
object's dma-buf or test for an imported buffer. The import_attach
field in struct drm_gem_object is an artifact of the import process,
but should not be used otherwise.

The helper drm_gem_is_imported() tests if a GEM object's buffer
has been imported into the driver. The corresponding dma-buf is
referenced by the object itself. Both cases avoid import_attach.

Thomas Zimmermann (2):
  drm/tegra: Test for imported buffers with drm_gem_is_imported()
  drm/tegra: Use dma_buf from GEM object instance

 drivers/gpu/drm/tegra/gem.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

-- 
2.49.0

[PATCH 2/2] drm/tegra: Use dma_buf from GEM object instance

[Thomas Zimmermann]

Avoid dereferencing struct drm_gem_object.import_attach for the
imported dma-buf. The dma_buf field in the GEM object instance refers
to the same buffer. Prepares to make import_attach optional.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
---
 drivers/gpu/drm/tegra/gem.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/tegra/gem.c b/drivers/gpu/drm/tegra/gem.c
index c1695caec956..e17abe63c723 100644
--- a/drivers/gpu/drm/tegra/gem.c
+++ b/drivers/gpu/drm/tegra/gem.c
@@ -527,7 +527,7 @@ void tegra_bo_free_object(struct drm_gem_object *gem)
 		if (drm_gem_is_imported(gem)) {
 			dma_buf_unmap_attachment_unlocked(gem->import_attach, bo->sgt,
 							  DMA_TO_DEVICE);
-			dma_buf_detach(gem->import_attach->dmabuf, gem->import_attach);
+			dma_buf_detach(gem->dma_buf, gem->import_attach);
 		}
 	}
 
-- 
2.49.0