[RFC,2/2] drm/prime: find gem object from the reimported dma-buf
Commit Message
Reimported dma-buf can reuse same gem object only when prime import
is done with same drm open context. So prime import is done with
other drm open context, gem object is newly created and mapped even
there is already mapped gem object. To avoid recreating gem object,
importer private data can be used at reimport time if it is assigned
with drm gem object at first import.
This can also remove remapping dma address for the hardware having
its own iommu.
Signed-off-by: Seung-Woo Kim <sw0312.kim@samsung.com>
---
drivers/gpu/drm/drm_prime.c | 19 ++++++++++++++-----
drivers/gpu/drm/exynos/exynos_drm_dmabuf.c | 1 +
drivers/gpu/drm/i915/i915_gem_dmabuf.c | 1 +
drivers/gpu/drm/udl/udl_gem.c | 1 +
4 files changed, 17 insertions(+), 5 deletions(-)
@@ -294,6 +294,7 @@ struct drm_gem_object *drm_gem_prime_import(struct drm_device *dev,
}
obj->import_attach = attach;
+ attach->importer_priv = obj;
return obj;
@@ -312,6 +313,7 @@ int drm_gem_prime_fd_to_handle(struct drm_device *dev,
{
struct dma_buf *dma_buf;
struct drm_gem_object *obj;
+ struct dma_buf_attachment *attach;
int ret;
dma_buf = dma_buf_get(prime_fd);
@@ -327,11 +329,18 @@ int drm_gem_prime_fd_to_handle(struct drm_device *dev,
goto out_put;
}
- /* never seen this one, need to import */
- obj = dev->driver->gem_prime_import(dev, dma_buf);
- if (IS_ERR(obj)) {
- ret = PTR_ERR(obj);
- goto out_put;
+ attach = dma_buf_get_attachment(dma_buf, dev->dev);
+ if (IS_ERR(attach)) {
+ /* never seen this one, need to import */
+ obj = dev->driver->gem_prime_import(dev, dma_buf);
+ if (IS_ERR(obj)) {
+ ret = PTR_ERR(obj);
+ goto out_put;
+ }
+ } else {
+ /* found attachment to same device */
+ obj = attach->importer_priv;
+ drm_gem_object_reference(obj);
}
ret = drm_gem_handle_create(file_priv, obj, handle);
@@ -285,6 +285,7 @@ struct drm_gem_object *exynos_dmabuf_prime_import(struct drm_device *drm_dev,
exynos_gem_obj->buffer = buffer;
buffer->sgt = sgt;
exynos_gem_obj->base.import_attach = attach;
+ attach->importer_priv = &exynos_gem_obj->base;
DRM_DEBUG_PRIME("dma_addr = 0x%x, size = 0x%lx\n", buffer->dma_addr,
buffer->size);
@@ -297,6 +297,7 @@ struct drm_gem_object *i915_gem_prime_import(struct drm_device *dev,
i915_gem_object_init(obj, &i915_gem_object_dmabuf_ops);
obj->base.import_attach = attach;
+ attach->importer_priv = &obj->base;
return &obj->base;
@@ -317,6 +317,7 @@ struct drm_gem_object *udl_gem_prime_import(struct drm_device *dev,
}
uobj->base.import_attach = attach;
+ attach->importer_priv = &uobj->base;
return &uobj->base;