linux-stable.git/rust/kernel/drm, branch master

rust: drm: gem: shmem: Add DRM shmem helper abstraction

2026-03-27T20:38:40+00:00

The DRM shmem helper includes common code useful for drivers which
allocate GEM objects as anonymous shmem. Add a Rust abstraction for
this. Drivers can choose the raw GEM implementation or the shmem layer,
depending on their needs.

Signed-off-by: Asahi Lina 
Signed-off-by: Daniel Almeida 
Reviewed-by: Daniel Almeida 
Signed-off-by: Lyude Paul 
Reviewed-by: Janne Grunau 
Tested-by: Deborah Brouwer 
Link: https://patch.msgid.link/20260316211646.650074-6-lyude@redhat.com
[ * DRM_GEM_SHMEM_HELPER is a tristate; when a module driver selects it,
    it becomes =m. The Rust kernel crate and its C helpers are always
    built into vmlinux and can't reference symbols from a module,
    causing link errors.

    Thus, add RUST_DRM_GEM_SHMEM_HELPER bool Kconfig that selects
    DRM_GEM_SHMEM_HELPER, forcing it built-in when Rust drivers need it;
    use cfg(CONFIG_RUST_DRM_GEM_SHMEM_HELPER) for the shmem module.

  * Add cfg_attr(not(CONFIG_RUST_DRM_GEM_SHMEM_HELPER), expect(unused))
    on pub(crate) use impl_aref_for_gem_obj and BaseObjectPrivate, so
    that unused warnings are suppressed when shmem is not enabled.

  * Enable const_refs_to_static (stabilized in 1.83) to prevent build
    errors with older compilers.

  * Use &raw const for bindings::drm_gem_shmem_vm_ops and add
    #[allow(unused_unsafe, reason = "Safe since Rust 1.82.0")].

  * Fix incorrect C Header path and minor spelling and formatting
    issues.

  * Drop shmem::Object::sg_table() as the current implementation is
    unsound.

    - Danilo ]
Signed-off-by: Danilo Krummrich

rust: drm: gem: Add raw_dma_resv() function

2026-03-27T20:37:45+00:00

For retrieving a pointer to the struct dma_resv for a given GEM object. We
also introduce it in a new trait, BaseObjectPrivate, which we automatically
implement for all gem objects and don't expose to users outside of the
crate.

Signed-off-by: Lyude Paul 
Reviewed-by: Janne Grunau 
Tested-by: Janne Grunau 
Tested-by: Deborah Brouwer 
Link: https://patch.msgid.link/20260316211646.650074-3-lyude@redhat.com
[ Fix incorrect reference in safety comment. - Danilo ]
Signed-off-by: Danilo Krummrich

rust: drm: use new sync::aref path for imports

2026-03-26T15:45:49+00:00

ARef and AlwaysRefCounted are being moved to sync::aref, and the
re-exports under types are planned to be removed. Thus, update imports
to the new path.

Acked-by: Danilo Krummrich 
Reviewed-by: Gary Guo 
Link: https://patch.msgid.link/20260326-drm-rust-next-fix-aref-v1-2-7f6f58d2828a@google.com
Signed-off-by: Alice Ryhl

rust: drm: dispatch delayed work items to the private data

2026-03-26T13:08:49+00:00

Much like the patch that dispatched (regular) work items, we also need to
dispatch delayed work items in order not to trigger the orphan rule. This
allows a drm::Device to dispatch the delayed work to T::Data.

Reviewed-by: Alice Ryhl 
Acked-by: Danilo Krummrich 
Signed-off-by: Daniel Almeida 
Link: https://lore.kernel.org/r/20260323-aref-workitem-v3-4-f59729b812aa@collabora.com
Signed-off-by: Alice Ryhl

rust: drm: dispatch work items to the private data

2026-03-26T13:08:48+00:00

This implementation dispatches any work enqueued on ARef> to
its driver-provided handler. It does so by building upon the newly-added
ARef support in workqueue.rs in order to call into the driver
implementations for work_container_of and raw_get_work.

This is notably important for work items that need access to the drm
device, as it was not possible to enqueue work on a ARef>
previously without failing the orphan rule.

The current implementation needs T::Data to live inline with drm::Device in
order for work_container_of to function. This restriction is already
captured by the trait bounds. Drivers that need to share their ownership of
T::Data may trivially get around this:

// Lives inline in drm::Device
struct DataWrapper {
  work: ...,
  // Heap-allocated, shared ownership.
  data: Arc,
}

Reviewed-by: Alice Ryhl 
Acked-by: Danilo Krummrich 
Signed-off-by: Daniel Almeida 
Link: https://lore.kernel.org/r/20260323-aref-workitem-v3-2-f59729b812aa@collabora.com
Signed-off-by: Alice Ryhl

rust: gem: Introduce DriverObject::Args

2026-03-26T01:08:04+00:00

This is an associated type that may be used in order to specify a
data-type to pass to gem objects when constructing them, allowing for
drivers to more easily initialize their private-data for gem objects.

Signed-off-by: Lyude Paul 
Reviewed-by: Alice Ryhl 
Reviewed-by: Daniel Almeida 
Reviewed-by: Janne Grunau 
Tested-by: Deborah Brouwer 
Link: https://patch.msgid.link/20260316211646.650074-5-lyude@redhat.com
[ Resolve merge conflicts in Tyr. - Danilo ]
Signed-off-by: Danilo Krummrich

rust: drm: Add gem::impl_aref_for_gem_obj!

2026-03-26T01:05:29+00:00

In the future we're going to be introducing more GEM object types in rust
then just gem::Object. Since all types of GEM objects have refcounting,
let's introduce a macro that we can use in the gem crate in order to copy
this boilerplate implementation for each type: impl_aref_for_gem_obj!().

Signed-off-by: Lyude Paul 
Reviewed-by: Daniel Almeida 
Reviewed-by: Janne Grunau 
Tested-by: Deborah Brouwer 
Link: https://patch.msgid.link/20260316211646.650074-2-lyude@redhat.com
[ Resolve merge conflicts. - Danilo ]
Signed-off-by: Danilo Krummrich

rust/drm: Remove imports covered by prelude::*

2026-02-24T15:11:41+00:00

This just removes any explicit imports of items in files that are already
being pulled in by `use prelude::*;`.

There should be no functional changes in this patch.

Signed-off-by: Lyude Paul 
Link: https://patch.msgid.link/20260122214316.3281257-2-lyude@redhat.com
Signed-off-by: Danilo Krummrich

rust/drm: Fixup import styles

2026-02-24T15:10:09+00:00

This is to match
  https://docs.kernel.org/rust/coding-guidelines.html#imports

There should be no functional changes in this patch.

Signed-off-by: Lyude Paul 
Link: https://patch.msgid.link/20260122214316.3281257-1-lyude@redhat.com
[ Move trailing `//` at the end. - Danilo ]
Signed-off-by: Danilo Krummrich

rust/drm: Fix Registration::{new,new_foreign_owned}() docs

2026-01-23T19:18:07+00:00

Looks like we've actually had a malformed rustdoc reference in the rustdocs
for Registration::new_foreign_owned() for a while that, when fixed, still
couldn't resolve properly because it refers to a private item.

This is probably leftover from when Registration::new() was public, so drop
the documentation from that function and fixup the documentation for
Registration::new_foreign_owned().

Signed-off-by: Lyude Paul 
Acked-by: Danilo Krummrich 
Fixes: 0600032c54b7 ("rust: drm: add DRM driver registration")
Cc:  # v6.16+
Link: https://patch.msgid.link/20260122221037.3462081-1-lyude@redhat.com