[Diffusion] Register HWR mmap for direct DLO H2D (#6591)

Signed-off-by: Hongsheng Liu <liuhongsheng4@huawei.com>
Signed-off-by: hsliuustc0106 <hsliuustc0106@users.noreply.github.com>
Co-authored-by: hsliuustc0106 <hsliuustc0106@users.noreply.github.com>

tests/diffusion/model_loader/test_diffusers_loader.py

@@ -24,6 +24,7 @@ from vllm_omni.diffusion.model_loader.host_weight_plan import (
     HostWeightPlanResult,
     TensorBinding,
 )
+from vllm_omni.diffusion.model_loader.host_weights import source_identity as source_identity_module
 from vllm_omni.diffusion.models.helios import HeliosPipeline
 from vllm_omni.diffusion.models.host_weight_contract import FinalLayoutModelContract
 from vllm_omni.diffusion.registry import initialize_model
@@ -173,6 +174,15 @@ def test_hwr_cold_publication_and_warm_restore_skip_ordinary_dit_loading(
         str(canonical_root / "model.safetensors"),
     )
     store_root = tmp_path / "hwr-store"
+    hash_calls = 0
+    original_sha256 = source_identity_module._sha256_file
+
+    def counted_sha256(path: Path, state: object) -> str:
+        nonlocal hash_calls
+        hash_calls += 1
+        return original_sha256(path, state)  # type: ignore[arg-type]
+
+    monkeypatch.setattr(source_identity_module, "_sha256_file", counted_sha256)
 
     def make_loader() -> tuple[DiffusersPipelineLoader, _HWRPipeline]:
         loader = DiffusersPipelineLoader(LoadConfig(), _hwr_config(canonical_root, store_root))
@@ -205,6 +215,8 @@ def test_hwr_cold_publication_and_warm_restore_skip_ordinary_dit_loading(
     assert warm_plan is not None
     assert warm_plan.lease_carrier is not None
     warm_plan.lease_carrier.close()
+    assert hash_calls == 1
+    assert len(tuple((store_root / "source-digests-v1" / "entries").glob("*.json"))) == 1
 
 
 def test_hwr_commit_failure_discards_model_and_reloads_without_hwr_or_mmap(tmp_path: Path, monkeypatch):