[Core] Sharded State Loader download from HF (#4889)

vllm/model_executor/model_loader/loader.py

@@ -423,6 +423,16 @@ class ShardedStateLoader(BaseModelLoader):
                     result[k] = t
         return result
 
+    def _prepare_weights(self, model_name_or_path: str,
+                         revision: Optional[str]):
+        if os.path.isdir(model_name_or_path):
+            return model_name_or_path
+        else:
+            allow_patterns = ["*.safetensors"]
+            return download_weights_from_hf(model_name_or_path,
+                                            self.load_config.download_dir,
+                                            allow_patterns, revision)
+
     def load_model(self, *, model_config: ModelConfig,
                    device_config: DeviceConfig,
                    lora_config: Optional[LoRAConfig],
@@ -433,6 +443,10 @@ class ShardedStateLoader(BaseModelLoader):
         from safetensors.torch import safe_open
 
         from vllm.distributed import get_tensor_model_parallel_rank
+
+        local_model_path = self._prepare_weights(model_config.model,
+                                                 model_config.revision)
+
         with set_default_torch_dtype(model_config.dtype):
             with torch.device(device_config.device):
                 model = _initialize_model(model_config, self.load_config,
@@ -440,7 +454,7 @@ class ShardedStateLoader(BaseModelLoader):
                                           cache_config)
             rank = get_tensor_model_parallel_rank()
             pattern = os.path.join(
-                model_config.model,
+                local_model_path,
                 self.pattern.format(rank=rank, part="*"),
             )
             filepaths = glob.glob(pattern)