| Message ID | 20250318-drm-gem-shmem-v1-5-64b96511a84f@collabora.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | Rust abstractions for shmem-backed GEM objects | expand |
Am 18.03.25 um 20:22 schrieb Daniel Almeida: > From: Asahi Lina <lina@asahilina.net> > > Drivers may want to support driver-private objects, which cannot be > shared. This allows them to share a single lock and enables other > optimizations. > > Add an `exportable` field to drm_gem_object, which blocks PRIME export > if set to false. It is initialized to true in > drm_gem_private_object_init. We already have a method for doing that which is used by almost all drivers (except for lsdc). Basically you just create a function which checks the per-requisites if a buffer can be exported before calling drm_gem_prime_export() and installs that as .export callback into the drm_gem_object_funcs. See amdgpu_gem_prime_export() for a simpler example. Regards, Christian. > > Signed-off-by: Asahi Lina <lina@asahilina.net> > Signed-off-by: Daniel Almeida <daniel.almeida@collabora.com> > --- > drivers/gpu/drm/drm_gem.c | 1 + > drivers/gpu/drm/drm_prime.c | 5 +++++ > include/drm/drm_gem.h | 8 ++++++++ > 3 files changed, 14 insertions(+) > > diff --git a/drivers/gpu/drm/drm_gem.c b/drivers/gpu/drm/drm_gem.c > index ee811764c3df4b4e9c377a66afd4967512ba2001..8f998fe6beecd285ce3e2d5badfa95eb7d7bd548 100644 > --- a/drivers/gpu/drm/drm_gem.c > +++ b/drivers/gpu/drm/drm_gem.c > @@ -195,6 +195,7 @@ void drm_gem_private_object_init(struct drm_device *dev, > > drm_vma_node_reset(&obj->vma_node); > INIT_LIST_HEAD(&obj->lru_node); > + obj->exportable = true; > } > EXPORT_SYMBOL(drm_gem_private_object_init); > > diff --git a/drivers/gpu/drm/drm_prime.c b/drivers/gpu/drm/drm_prime.c > index 32a8781cfd67b82ece7b7b94625715171bb41917..20aa350280abe9a6ed6742e131ff50c65bc9dfa9 100644 > --- a/drivers/gpu/drm/drm_prime.c > +++ b/drivers/gpu/drm/drm_prime.c > @@ -387,6 +387,11 @@ static struct dma_buf *export_and_register_object(struct drm_device *dev, > return dmabuf; > } > > + if (!obj->exportable) { > + dmabuf = ERR_PTR(-EINVAL); > + return dmabuf; > + } > + > if (obj->funcs && obj->funcs->export) > dmabuf = obj->funcs->export(obj, flags); > else > diff --git a/include/drm/drm_gem.h b/include/drm/drm_gem.h > index fdae947682cd0b7b06db5e35e120f049a0f30179..f700e4996eccb92597cca6b8c3df8e35b864c1e1 100644 > --- a/include/drm/drm_gem.h > +++ b/include/drm/drm_gem.h > @@ -432,6 +432,14 @@ struct drm_gem_object { > * The current LRU list that the GEM object is on. > */ > struct drm_gem_lru *lru; > + > + /** > + * @exportable: > + * > + * Whether this GEM object can be exported via the drm_gem_object_funcs->export > + * callback. Defaults to true. > + */ > + bool exportable; > }; > > /** >
diff --git a/drivers/gpu/drm/drm_gem.c b/drivers/gpu/drm/drm_gem.c index ee811764c3df4b4e9c377a66afd4967512ba2001..8f998fe6beecd285ce3e2d5badfa95eb7d7bd548 100644 --- a/drivers/gpu/drm/drm_gem.c +++ b/drivers/gpu/drm/drm_gem.c @@ -195,6 +195,7 @@ void drm_gem_private_object_init(struct drm_device *dev, drm_vma_node_reset(&obj->vma_node); INIT_LIST_HEAD(&obj->lru_node); + obj->exportable = true; } EXPORT_SYMBOL(drm_gem_private_object_init); diff --git a/drivers/gpu/drm/drm_prime.c b/drivers/gpu/drm/drm_prime.c index 32a8781cfd67b82ece7b7b94625715171bb41917..20aa350280abe9a6ed6742e131ff50c65bc9dfa9 100644 --- a/drivers/gpu/drm/drm_prime.c +++ b/drivers/gpu/drm/drm_prime.c @@ -387,6 +387,11 @@ static struct dma_buf *export_and_register_object(struct drm_device *dev, return dmabuf; } + if (!obj->exportable) { + dmabuf = ERR_PTR(-EINVAL); + return dmabuf; + } + if (obj->funcs && obj->funcs->export) dmabuf = obj->funcs->export(obj, flags); else diff --git a/include/drm/drm_gem.h b/include/drm/drm_gem.h index fdae947682cd0b7b06db5e35e120f049a0f30179..f700e4996eccb92597cca6b8c3df8e35b864c1e1 100644 --- a/include/drm/drm_gem.h +++ b/include/drm/drm_gem.h @@ -432,6 +432,14 @@ struct drm_gem_object { * The current LRU list that the GEM object is on. */ struct drm_gem_lru *lru; + + /** + * @exportable: + * + * Whether this GEM object can be exported via the drm_gem_object_funcs->export + * callback. Defaults to true. + */ + bool exportable; }; /**