Add get_hidden_dim to qwen3.py for correct lora (#7312)

python/sglang/srt/models/qwen3.py

@@ -330,6 +330,30 @@ class Qwen3ForCausalLM(nn.Module):
     def get_input_embeddings(self, input_ids: torch.Tensor) -> torch.Tensor:
         return self.model.get_input_embeddings(input_ids)
 
+    def get_hidden_dim(self, module_name: str) -> Tuple[int]:
+        # return input_dim, output_dim
+        if module_name in ["q_proj", "qkv_proj"]:
+            return (
+                self.config.hidden_size,
+                self.config.head_dim * self.config.num_attention_heads,
+            )
+        elif module_name in ["o_proj"]:
+            return (
+                self.config.head_dim * self.config.num_attention_heads,
+                self.config.hidden_size,
+            )
+        elif module_name in ["kv_proj"]:
+            return (
+                self.config.hidden_size,
+                self.config.head_dim * self.config.num_key_value_heads,
+            )
+        elif module_name == "gate_up_proj":
+            return self.config.hidden_size, self.config.intermediate_size
+        elif module_name == "down_proj":
+            return self.config.intermediate_size, self.config.hidden_size
+        else:
+            raise NotImplementedError()
+
     @torch.no_grad()
     def forward(
         self,