drm/gpuvm: rust: add RUST_DRM_GPUVM option to Kconfig

Since Rust uses GPUVM via the kernel crate, which is built-in, the GPUVM
module must also be built-in to use GPUVM from Rust. Adjust the Kconfig
settings accordingly.

Suggested-by: Danilo Krummrich <dakr@kernel.org>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Link: https://patch.msgid.link/20260427-gpuvm-config-v1-1-8ece03771f8a@google.com
Signed-off-by: Danilo Krummrich <dakr@kernel.org>

drivers/gpu/drm/Kconfig

@@ -218,6 +218,13 @@ config DRM_GPUVM
 	  GPU-VM representation providing helpers to manage a GPUs virtual
 	  address space
 
+config RUST_DRM_GPUVM
+	bool
+	depends on DRM
+	select DRM_GPUVM
+	help
+	  Choose this if you need GPUVM functions in Rust
+
 config DRM_GPUSVM
 	tristate
 	depends on DRM

rust/helpers/drm_gpuvm.c

@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0 or MIT
 
-#ifdef CONFIG_DRM_GPUVM
+#ifdef CONFIG_RUST_DRM_GPUVM
 
 #include <drm/drm_gpuvm.h>
 
@@ -23,4 +23,4 @@ bool rust_helper_drm_gpuvm_is_extobj(struct drm_gpuvm *gpuvm,
 	return drm_gpuvm_is_extobj(gpuvm, obj);
 }
 
-#endif // CONFIG_DRM_GPUVM
+#endif // CONFIG_RUST_DRM_GPUVM

rust/kernel/drm/gpuvm/mod.rs

@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0 OR MIT
 
-#![cfg(CONFIG_DRM_GPUVM = "y")]
+#![cfg(CONFIG_RUST_DRM_GPUVM)]
 
 //! DRM GPUVM in immediate mode
 //!