[LoRA] introduce `LoraBaseMixin` to promote reusability. (#8670)

* introduce  to promote reusability.

* up

* add more tests

* up

* remove comments.

* fix fuse_nan test

* clarify the scope of fuse_lora and unfuse_lora

* remove space

docs/source/en/api/loaders/lora.md

@@ -12,10 +12,13 @@ specific language governing permissions and limitations under the License.
 
 # LoRA
 
-LoRA is a fast and lightweight training method that inserts and trains a significantly smaller number of parameters instead of all the model parameters. This produces a smaller file (~100 MBs) and makes it easier to quickly train a model to learn a new concept. LoRA weights are typically loaded into the UNet, text encoder or both. There are two classes for loading LoRA weights:
+LoRA is a fast and lightweight training method that inserts and trains a significantly smaller number of parameters instead of all the model parameters. This produces a smaller file (~100 MBs) and makes it easier to quickly train a model to learn a new concept. LoRA weights are typically loaded into the denoiser, text encoder or both. The denoiser usually corresponds to a UNet ([`UNet2DConditionModel`], for example) or a Transformer ([`SD3Transformer2DModel`], for example). There are several classes for loading LoRA weights:
 
 - [`LoraLoaderMixin`] provides functions for loading and unloading, fusing and unfusing, enabling and disabling, and more functions for managing LoRA weights. This class can be used with any model.
 - [`StableDiffusionXLLoraLoaderMixin`] is a [Stable Diffusion (SDXL)](../../api/pipelines/stable_diffusion/stable_diffusion_xl) version of the [`LoraLoaderMixin`] class for loading and saving LoRA weights. It can only be used with the SDXL model.
+- [`SD3LoraLoaderMixin`] provides similar functions for [Stable Diffusion 3](https://huggingface.co/blog/sd3).
+- [`AmusedLoraLoaderMixin`] is for the [`AmusedPipeline`].
+- [`LoraBaseMixin`] provides a base class with several utility methods to fuse, unfuse, unload, LoRAs and more.
 
 <Tip>
 
@@ -29,4 +32,16 @@ To learn more about how to load LoRA weights, see the [LoRA](../../using-diffuse
 
 ## StableDiffusionXLLoraLoaderMixin
 
-[[autodoc]] loaders.lora.StableDiffusionXLLoraLoaderMixin
\ No newline at end of file
+[[autodoc]] loaders.lora.StableDiffusionXLLoraLoaderMixin
+
+## SD3LoraLoaderMixin
+
+[[autodoc]] loaders.lora.SD3LoraLoaderMixin
+
+## AmusedLoraLoaderMixin
+
+[[autodoc]] loaders.lora.AmusedLoraLoaderMixin
+
+## LoraBaseMixin
+
+[[autodoc]] loaders.lora_base.LoraBaseMixin
\ No newline at end of file

examples/amused/train_amused.py

@@ -41,7 +41,7 @@ from transformers import (
 
 import diffusers.optimization
 from diffusers import AmusedPipeline, AmusedScheduler, EMAModel, UVit2DModel, VQModel
-from diffusers.loaders import LoraLoaderMixin
+from diffusers.loaders import AmusedLoraLoaderMixin
 from diffusers.utils import is_wandb_available
 
 
@@ -532,7 +532,7 @@ def main(args):
                 weights.pop()
 
             if transformer_lora_layers_to_save is not None or text_encoder_lora_layers_to_save is not None:
-                LoraLoaderMixin.save_lora_weights(
+                AmusedLoraLoaderMixin.save_lora_weights(
                     output_dir,
                     transformer_lora_layers=transformer_lora_layers_to_save,
                     text_encoder_lora_layers=text_encoder_lora_layers_to_save,
@@ -566,11 +566,11 @@ def main(args):
                 raise ValueError(f"unexpected save model: {model.__class__}")
 
         if transformer is not None or text_encoder_ is not None:
-            lora_state_dict, network_alphas = LoraLoaderMixin.lora_state_dict(input_dir)
-            LoraLoaderMixin.load_lora_into_text_encoder(
+            lora_state_dict, network_alphas = AmusedLoraLoaderMixin.lora_state_dict(input_dir)
+            AmusedLoraLoaderMixin.load_lora_into_text_encoder(
                 lora_state_dict, network_alphas=network_alphas, text_encoder=text_encoder_
             )
-            LoraLoaderMixin.load_lora_into_transformer(
+            AmusedLoraLoaderMixin.load_lora_into_transformer(
                 lora_state_dict, network_alphas=network_alphas, transformer=transformer
             )
 

src/diffusers/loaders/__init__.py

@@ -55,11 +55,18 @@ _import_structure = {}
 
 if is_torch_available():
     _import_structure["single_file_model"] = ["FromOriginalModelMixin"]
+    _import_structure["transformer_sd3"] = ["SD3TransformerLoadersMixin"]
+
     _import_structure["unet"] = ["UNet2DConditionLoadersMixin"]
     _import_structure["utils"] = ["AttnProcsLayers"]
     if is_transformers_available():
         _import_structure["single_file"] = ["FromSingleFileMixin"]
-        _import_structure["lora"] = ["LoraLoaderMixin", "StableDiffusionXLLoraLoaderMixin", "SD3LoraLoaderMixin"]
+        _import_structure["lora"] = [
+            "AmusedLoraLoaderMixin",
+            "LoraLoaderMixin",
+            "SD3LoraLoaderMixin",
+            "StableDiffusionXLLoraLoaderMixin",
+        ]
         _import_structure["textual_inversion"] = ["TextualInversionLoaderMixin"]
         _import_structure["ip_adapter"] = ["IPAdapterMixin"]
 
@@ -69,12 +76,18 @@ _import_structure["peft"] = ["PeftAdapterMixin"]
 if TYPE_CHECKING or DIFFUSERS_SLOW_IMPORT:
     if is_torch_available():
         from .single_file_model import FromOriginalModelMixin
+        from .transformer_sd3 import SD3TransformerLoadersMixin
         from .unet import UNet2DConditionLoadersMixin
         from .utils import AttnProcsLayers
 
         if is_transformers_available():
             from .ip_adapter import IPAdapterMixin
-            from .lora import LoraLoaderMixin, SD3LoraLoaderMixin, StableDiffusionXLLoraLoaderMixin
+            from .lora import (
+                AmusedLoraLoaderMixin,
+                LoraLoaderMixin,
+                SD3LoraLoaderMixin,
+                StableDiffusionXLLoraLoaderMixin,
+            )
             from .single_file import FromSingleFileMixin
             from .textual_inversion import TextualInversionLoaderMixin
 

src/diffusers/loaders/transformer_sd3.py

+import inspect
+from functools import partial
+from typing import Dict, List, Optional, Union
+
+import torch.nn as nn
+
+from ..utils import (
+    USE_PEFT_BACKEND,
+    delete_adapter_layers,
+    is_accelerate_available,
+    logging,
+    set_adapter_layers,
+    set_weights_and_activate_adapters,
+)
+from .lora import TEXT_ENCODER_NAME, TRANSFORMER_NAME
+
+
+if is_accelerate_available():
+    from accelerate.hooks import AlignDevicesHook, CpuOffload, remove_hook_from_module
+
+logger = logging.get_logger(__name__)
+
+
+class SD3TransformerLoadersMixin:
+    """
+    Load LoRA layers into a [`SD3Transformer2DModel`].
+    """
+
+    text_encoder_name = TEXT_ENCODER_NAME
+    transformer_name = TRANSFORMER_NAME
+
+    @classmethod
+    # Copied from diffusers.loaders.lora_base.LoraBaseMixin._optionally_disable_offloading
+    def _optionally_disable_offloading(cls, _pipeline):
+        """
+        Optionally removes offloading in case the pipeline has been already sequentially offloaded to CPU.
+
+        Args:
+            _pipeline (`DiffusionPipeline`):
+                The pipeline to disable offloading for.
+
+        Returns:
+            tuple:
+                A tuple indicating if `is_model_cpu_offload` or `is_sequential_cpu_offload` is True.
+        """
+        is_model_cpu_offload = False
+        is_sequential_cpu_offload = False
+
+        if _pipeline is not None and _pipeline.hf_device_map is None:
+            for _, component in _pipeline.components.items():
+                if isinstance(component, nn.Module) and hasattr(component, "_hf_hook"):
+                    if not is_model_cpu_offload:
+                        is_model_cpu_offload = isinstance(component._hf_hook, CpuOffload)
+                    if not is_sequential_cpu_offload:
+                        is_sequential_cpu_offload = (
+                            isinstance(component._hf_hook, AlignDevicesHook)
+                            or hasattr(component._hf_hook, "hooks")
+                            and isinstance(component._hf_hook.hooks[0], AlignDevicesHook)
+                        )
+
+                    logger.info(
+                        "Accelerate hooks detected. Since you have called `load_lora_weights()`, the previous hooks will be first removed. Then the LoRA parameters will be loaded and the hooks will be applied again."
+                    )
+                    remove_hook_from_module(component, recurse=is_sequential_cpu_offload)
+
+        return (is_model_cpu_offload, is_sequential_cpu_offload)
+
+    # Copied from diffusers.loaders.unet.UNet2DConditionLoadersMixin.fuse_lora
+    def fuse_lora(self, lora_scale=1.0, safe_fusing=False, adapter_names=None):
+        if not USE_PEFT_BACKEND:
+            raise ValueError("PEFT backend is required for `fuse_lora()`.")
+
+        self.lora_scale = lora_scale
+        self._safe_fusing = safe_fusing
+        self.apply(partial(self._fuse_lora_apply, adapter_names=adapter_names))
+
+    # Copied from diffusers.loaders.unet.UNet2DConditionLoadersMixin._fuse_lora_apply
+    def _fuse_lora_apply(self, module, adapter_names=None):
+        from peft.tuners.tuners_utils import BaseTunerLayer
+
+        merge_kwargs = {"safe_merge": self._safe_fusing}
+
+        if isinstance(module, BaseTunerLayer):
+            if self.lora_scale != 1.0:
+                module.scale_layer(self.lora_scale)
+
+            # For BC with prevous PEFT versions, we need to check the signature
+            # of the `merge` method to see if it supports the `adapter_names` argument.
+            supported_merge_kwargs = list(inspect.signature(module.merge).parameters)
+            if "adapter_names" in supported_merge_kwargs:
+                merge_kwargs["adapter_names"] = adapter_names
+            elif "adapter_names" not in supported_merge_kwargs and adapter_names is not None:
+                raise ValueError(
+                    "The `adapter_names` argument is not supported with your PEFT version. Please upgrade"
+                    " to the latest version of PEFT. `pip install -U peft`"
+                )
+
+            module.merge(**merge_kwargs)
+
+    # Copied from diffusers.loaders.unet.UNet2DConditionLoadersMixin.unfuse_lora
+    def unfuse_lora(self):
+        if not USE_PEFT_BACKEND:
+            raise ValueError("PEFT backend is required for `unfuse_lora()`.")
+        self.apply(self._unfuse_lora_apply)
+
+    # Copied from diffusers.loaders.unet.UNet2DConditionLoadersMixin._unfuse_lora_apply
+    def _unfuse_lora_apply(self, module):
+        from peft.tuners.tuners_utils import BaseTunerLayer
+
+        if isinstance(module, BaseTunerLayer):
+            module.unmerge()
+
+    # Copied from diffusers.loaders.unet.UNet2DConditionLoadersMixin.unload_lora
+    def unload_lora(self):
+        if not USE_PEFT_BACKEND:
+            raise ValueError("PEFT backend is required for `unload_lora()`.")
+
+        from ..utils import recurse_remove_peft_layers
+
+        recurse_remove_peft_layers(self)
+        if hasattr(self, "peft_config"):
+            del self.peft_config
+
+    # This class is almost the same but it doesn't do `_maybe_expand_lora_scales()` yet. We will work on adding
+    # this support in a future PR.
+    def set_adapters(
+        self,
+        adapter_names: Union[List[str], str],
+        weights: Optional[Union[float, Dict, List[float], List[Dict], List[None]]] = None,
+    ):
+        """
+        Set the currently active adapters for use in the Transformer.
+
+        Args:
+            adapter_names (`List[str]` or `str`):
+                The names of the adapters to use.
+            adapter_weights (`Union[List[float], float]`, *optional*):
+                The adapter(s) weights to use with the Transformer. If `None`, the weights are set to `1.0` for all the
+                adapters.
+
+        Example:
+
+        ```py
+        from diffusers import AutoPipelineForText2Image
+        import torch
+
+        pipeline = AutoPipelineForText2Image.from_pretrained(
+            "stabilityai/stable-diffusion-xl-base-1.0", torch_dtype=torch.float16
+        ).to("cuda")
+        pipeline.load_lora_weights(
+            "jbilcke-hf/sdxl-cinematic-1", weight_name="pytorch_lora_weights.safetensors", adapter_name="cinematic"
+        )
+        pipeline.load_lora_weights("nerijs/pixel-art-xl", weight_name="pixel-art-xl.safetensors", adapter_name="pixel")
+        pipeline.set_adapters(["cinematic", "pixel"], adapter_weights=[0.5, 0.5])
+        ```
+        """
+        if not USE_PEFT_BACKEND:
+            raise ValueError("PEFT backend is required for `set_adapters()`.")
+
+        adapter_names = [adapter_names] if isinstance(adapter_names, str) else adapter_names
+
+        # Expand weights into a list, one entry per adapter
+        # examples for e.g. 2 adapters:  [{...}, 7] -> [7,7] ; None -> [None, None]
+        if not isinstance(weights, list):
+            weights = [weights] * len(adapter_names)
+
+        if len(adapter_names) != len(weights):
+            raise ValueError(
+                f"Length of adapter names {len(adapter_names)} is not equal to the length of their weights {len(weights)}."
+            )
+
+        # Set None values to default of 1.0
+        # e.g. [{...}, 7] -> [{...}, 7] ; [None, None] -> [1.0, 1.0]
+        weights = [w if w is not None else 1.0 for w in weights]
+
+        set_weights_and_activate_adapters(self, adapter_names, weights)
+
+    # Copied from diffusers.loaders.unet.UNet2DConditionLoadersMixin.disable_lora with UNet->Transformer
+    def disable_lora(self):
+        """
+        Disable the Transformer's active LoRA layers.
+
+        Example:
+
+        ```py
+        from diffusers import AutoPipelineForText2Image
+        import torch
+
+        pipeline = AutoPipelineForText2Image.from_pretrained(
+            "stabilityai/stable-diffusion-xl-base-1.0", torch_dtype=torch.float16
+        ).to("cuda")
+        pipeline.load_lora_weights(
+            "jbilcke-hf/sdxl-cinematic-1", weight_name="pytorch_lora_weights.safetensors", adapter_name="cinematic"
+        )
+        pipeline.disable_lora()
+        ```
+        """
+        if not USE_PEFT_BACKEND:
+            raise ValueError("PEFT backend is required for this method.")
+        set_adapter_layers(self, enabled=False)
+
+    # Copied from diffusers.loaders.unet.UNet2DConditionLoadersMixin.enable_lora with UNet->Transformer
+    def enable_lora(self):
+        """
+        Enable the Transformer's active LoRA layers.
+
+        Example:
+
+        ```py
+        from diffusers import AutoPipelineForText2Image
+        import torch
+
+        pipeline = AutoPipelineForText2Image.from_pretrained(
+            "stabilityai/stable-diffusion-xl-base-1.0", torch_dtype=torch.float16
+        ).to("cuda")
+        pipeline.load_lora_weights(
+            "jbilcke-hf/sdxl-cinematic-1", weight_name="pytorch_lora_weights.safetensors", adapter_name="cinematic"
+        )
+        pipeline.enable_lora()
+        ```
+        """
+        if not USE_PEFT_BACKEND:
+            raise ValueError("PEFT backend is required for this method.")
+        set_adapter_layers(self, enabled=True)
+
+    # Copied from diffusers.loaders.unet.UNet2DConditionLoadersMixin.delete_adapters with UNet->Transformer
+    def delete_adapters(self, adapter_names: Union[List[str], str]):
+        """
+        Delete an adapter's LoRA layers from the Transformer.
+
+        Args:
+            adapter_names (`Union[List[str], str]`):
+                The names (single string or list of strings) of the adapter to delete.
+
+        Example:
+
+        ```py
+        from diffusers import AutoPipelineForText2Image
+        import torch
+
+        pipeline = AutoPipelineForText2Image.from_pretrained(
+            "stabilityai/stable-diffusion-xl-base-1.0", torch_dtype=torch.float16
+        ).to("cuda")
+        pipeline.load_lora_weights(
+            "jbilcke-hf/sdxl-cinematic-1", weight_name="pytorch_lora_weights.safetensors", adapter_names="cinematic"
+        )
+        pipeline.delete_adapters("cinematic")
+        ```
+        """
+        if not USE_PEFT_BACKEND:
+            raise ValueError("PEFT backend is required for this method.")
+
+        if isinstance(adapter_names, str):
+            adapter_names = [adapter_names]
+
+        for adapter_name in adapter_names:
+            delete_adapter_layers(self, adapter_name)
+
+            # Pop also the corresponding adapter from the config
+            if hasattr(self, "peft_config"):
+                self.peft_config.pop(adapter_name, None)

src/diffusers/loaders/unet.py

@@ -362,7 +362,7 @@ class UNet2DConditionLoadersMixin:
         return is_model_cpu_offload, is_sequential_cpu_offload
 
     @classmethod
-    # Copied from diffusers.loaders.lora.LoraLoaderMixin._optionally_disable_offloading
+    # Copied from diffusers.loaders.lora_base.LoraBaseMixin._optionally_disable_offloading
     def _optionally_disable_offloading(cls, _pipeline):
         """
         Optionally removes offloading in case the pipeline has been already sequentially offloaded to CPU.

src/diffusers/models/transformers/transformer_sd3.py

@@ -13,15 +13,13 @@
 # limitations under the License.
 
 
-import inspect
-from functools import partial
 from typing import Any, Dict, List, Optional, Union
 
 import torch
 import torch.nn as nn
 
 from ...configuration_utils import ConfigMixin, register_to_config
-from ...loaders import FromOriginalModelMixin, PeftAdapterMixin
+from ...loaders import FromOriginalModelMixin, PeftAdapterMixin, SD3TransformerLoadersMixin
 from ...models.attention import JointTransformerBlock
 from ...models.attention_processor import Attention, AttentionProcessor
 from ...models.modeling_utils import ModelMixin
@@ -34,7 +32,9 @@ from ..modeling_outputs import Transformer2DModelOutput
 logger = logging.get_logger(__name__)  # pylint: disable=invalid-name
 
 
-class SD3Transformer2DModel(ModelMixin, ConfigMixin, PeftAdapterMixin, FromOriginalModelMixin):
+class SD3Transformer2DModel(
+    ModelMixin, ConfigMixin, PeftAdapterMixin, FromOriginalModelMixin, SD3TransformerLoadersMixin
+):
     """
     The Transformer model introduced in Stable Diffusion 3.
 
@@ -241,47 +241,6 @@ class SD3Transformer2DModel(ModelMixin, ConfigMixin, PeftAdapterMixin, FromOrigi
         if hasattr(module, "gradient_checkpointing"):
             module.gradient_checkpointing = value
 
-    def fuse_lora(self, lora_scale=1.0, safe_fusing=False, adapter_names=None):
-        if not USE_PEFT_BACKEND:
-            raise ValueError("PEFT backend is required for `fuse_lora()`.")
-
-        self.lora_scale = lora_scale
-        self._safe_fusing = safe_fusing
-        self.apply(partial(self._fuse_lora_apply, adapter_names=adapter_names))
-
-    def _fuse_lora_apply(self, module, adapter_names=None):
-        from peft.tuners.tuners_utils import BaseTunerLayer
-
-        merge_kwargs = {"safe_merge": self._safe_fusing}
-
-        if isinstance(module, BaseTunerLayer):
-            if self.lora_scale != 1.0:
-                module.scale_layer(self.lora_scale)
-
-            # For BC with prevous PEFT versions, we need to check the signature
-            # of the `merge` method to see if it supports the `adapter_names` argument.
-            supported_merge_kwargs = list(inspect.signature(module.merge).parameters)
-            if "adapter_names" in supported_merge_kwargs:
-                merge_kwargs["adapter_names"] = adapter_names
-            elif "adapter_names" not in supported_merge_kwargs and adapter_names is not None:
-                raise ValueError(
-                    "The `adapter_names` argument is not supported with your PEFT version. Please upgrade"
-                    " to the latest version of PEFT. `pip install -U peft`"
-                )
-
-            module.merge(**merge_kwargs)
-
-    def unfuse_lora(self):
-        if not USE_PEFT_BACKEND:
-            raise ValueError("PEFT backend is required for `unfuse_lora()`.")
-        self.apply(self._unfuse_lora_apply)
-
-    def _unfuse_lora_apply(self, module):
-        from peft.tuners.tuners_utils import BaseTunerLayer
-
-        if isinstance(module, BaseTunerLayer):
-            module.unmerge()
-
     def forward(
         self,
         hidden_states: torch.FloatTensor,

src/diffusers/pipelines/controlnet_sd3/pipeline_stable_diffusion_3_controlnet.py

@@ -30,9 +30,12 @@ from ...models.controlnet_sd3 import SD3ControlNetModel, SD3MultiControlNetModel
 from ...models.transformers import SD3Transformer2DModel
 from ...schedulers import FlowMatchEulerDiscreteScheduler
 from ...utils import (
+    USE_PEFT_BACKEND,
     is_torch_xla_available,
     logging,
     replace_example_docstring,
+    scale_lora_layers,
+    unscale_lora_layers,
 )
 from ...utils.torch_utils import randn_tensor
 from ..pipeline_utils import DiffusionPipeline
@@ -346,6 +349,7 @@ class StableDiffusion3ControlNetPipeline(DiffusionPipeline, SD3LoraLoaderMixin,
         negative_pooled_prompt_embeds: Optional[torch.FloatTensor] = None,
         clip_skip: Optional[int] = None,
         max_sequence_length: int = 256,
+        lora_scale: Optional[float] = None,
     ):
         r"""
 
@@ -391,9 +395,22 @@ class StableDiffusion3ControlNetPipeline(DiffusionPipeline, SD3LoraLoaderMixin,
             clip_skip (`int`, *optional*):
                 Number of layers to be skipped from CLIP while computing the prompt embeddings. A value of 1 means that
                 the output of the pre-final layer will be used for computing the prompt embeddings.
+            lora_scale (`float`, *optional*):
+                A lora scale that will be applied to all LoRA layers of the text encoder if LoRA layers are loaded.
         """
         device = device or self._execution_device
 
+        # set lora scale so that monkey patched LoRA
+        # function of text encoder can correctly access it
+        if lora_scale is not None and isinstance(self, SD3LoraLoaderMixin):
+            self._lora_scale = lora_scale
+
+            # dynamically adjust the LoRA scale
+            if self.text_encoder is not None and USE_PEFT_BACKEND:
+                scale_lora_layers(self.text_encoder, lora_scale)
+            if self.text_encoder_2 is not None and USE_PEFT_BACKEND:
+                scale_lora_layers(self.text_encoder_2, lora_scale)
+
         prompt = [prompt] if isinstance(prompt, str) else prompt
         if prompt is not None:
             batch_size = len(prompt)
@@ -496,6 +513,16 @@ class StableDiffusion3ControlNetPipeline(DiffusionPipeline, SD3LoraLoaderMixin,
                 [negative_pooled_prompt_embed, negative_pooled_prompt_2_embed], dim=-1
             )
 
+        if self.text_encoder is not None:
+            if isinstance(self, SD3LoraLoaderMixin) and USE_PEFT_BACKEND:
+                # Retrieve the original scale by scaling back the LoRA layers
+                unscale_lora_layers(self.text_encoder, lora_scale)
+
+        if self.text_encoder_2 is not None:
+            if isinstance(self, SD3LoraLoaderMixin) and USE_PEFT_BACKEND:
+                # Retrieve the original scale by scaling back the LoRA layers
+                unscale_lora_layers(self.text_encoder_2, lora_scale)
+
         return prompt_embeds, negative_prompt_embeds, pooled_prompt_embeds, negative_pooled_prompt_embeds
 
     def check_inputs(

src/diffusers/pipelines/stable_diffusion_3/pipeline_stable_diffusion_3.py

@@ -29,9 +29,12 @@ from ...models.autoencoders import AutoencoderKL
 from ...models.transformers import SD3Transformer2DModel
 from ...schedulers import FlowMatchEulerDiscreteScheduler
 from ...utils import (
+    USE_PEFT_BACKEND,
     is_torch_xla_available,
     logging,
     replace_example_docstring,
+    scale_lora_layers,
+    unscale_lora_layers,
 )
 from ...utils.torch_utils import randn_tensor
 from ..pipeline_utils import DiffusionPipeline
@@ -329,6 +332,7 @@ class StableDiffusion3Pipeline(DiffusionPipeline, SD3LoraLoaderMixin, FromSingle
         negative_pooled_prompt_embeds: Optional[torch.FloatTensor] = None,
         clip_skip: Optional[int] = None,
         max_sequence_length: int = 256,
+        lora_scale: Optional[float] = None,
     ):
         r"""
 
@@ -374,9 +378,22 @@ class StableDiffusion3Pipeline(DiffusionPipeline, SD3LoraLoaderMixin, FromSingle
             clip_skip (`int`, *optional*):
                 Number of layers to be skipped from CLIP while computing the prompt embeddings. A value of 1 means that
                 the output of the pre-final layer will be used for computing the prompt embeddings.
+            lora_scale (`float`, *optional*):
+                A lora scale that will be applied to all LoRA layers of the text encoder if LoRA layers are loaded.
         """
         device = device or self._execution_device
 
+        # set lora scale so that monkey patched LoRA
+        # function of text encoder can correctly access it
+        if lora_scale is not None and isinstance(self, SD3LoraLoaderMixin):
+            self._lora_scale = lora_scale
+
+            # dynamically adjust the LoRA scale
+            if self.text_encoder is not None and USE_PEFT_BACKEND:
+                scale_lora_layers(self.text_encoder, lora_scale)
+            if self.text_encoder_2 is not None and USE_PEFT_BACKEND:
+                scale_lora_layers(self.text_encoder_2, lora_scale)
+
         prompt = [prompt] if isinstance(prompt, str) else prompt
         if prompt is not None:
             batch_size = len(prompt)
@@ -479,6 +496,16 @@ class StableDiffusion3Pipeline(DiffusionPipeline, SD3LoraLoaderMixin, FromSingle
                 [negative_pooled_prompt_embed, negative_pooled_prompt_2_embed], dim=-1
             )
 
+        if self.text_encoder is not None:
+            if isinstance(self, SD3LoraLoaderMixin) and USE_PEFT_BACKEND:
+                # Retrieve the original scale by scaling back the LoRA layers
+                unscale_lora_layers(self.text_encoder, lora_scale)
+
+        if self.text_encoder_2 is not None:
+            if isinstance(self, SD3LoraLoaderMixin) and USE_PEFT_BACKEND:
+                # Retrieve the original scale by scaling back the LoRA layers
+                unscale_lora_layers(self.text_encoder_2, lora_scale)
+
         return prompt_embeds, negative_prompt_embeds, pooled_prompt_embeds, negative_pooled_prompt_embeds
 
     def check_inputs(
@@ -787,6 +814,9 @@ class StableDiffusion3Pipeline(DiffusionPipeline, SD3LoraLoaderMixin, FromSingle
 
         device = self._execution_device
 
+        lora_scale = (
+            self.joint_attention_kwargs.get("scale", None) if self.joint_attention_kwargs is not None else None
+        )
         (
             prompt_embeds,
             negative_prompt_embeds,
@@ -808,6 +838,7 @@ class StableDiffusion3Pipeline(DiffusionPipeline, SD3LoraLoaderMixin, FromSingle
             clip_skip=self.clip_skip,
             num_images_per_prompt=num_images_per_prompt,
             max_sequence_length=max_sequence_length,
+            lora_scale=lora_scale,
         )
 
         if self.do_classifier_free_guidance:

src/diffusers/pipelines/stable_diffusion_3/pipeline_stable_diffusion_3_img2img.py

@@ -25,13 +25,17 @@ from transformers import (
 )
 
 from ...image_processor import PipelineImageInput, VaeImageProcessor
+from ...loaders import SD3LoraLoaderMixin
 from ...models.autoencoders import AutoencoderKL
 from ...models.transformers import SD3Transformer2DModel
 from ...schedulers import FlowMatchEulerDiscreteScheduler
 from ...utils import (
+    USE_PEFT_BACKEND,
     is_torch_xla_available,
     logging,
     replace_example_docstring,
+    scale_lora_layers,
+    unscale_lora_layers,
 )
 from ...utils.torch_utils import randn_tensor
 from ..pipeline_utils import DiffusionPipeline
@@ -346,6 +350,7 @@ class StableDiffusion3Img2ImgPipeline(DiffusionPipeline):
         negative_pooled_prompt_embeds: Optional[torch.FloatTensor] = None,
         clip_skip: Optional[int] = None,
         max_sequence_length: int = 256,
+        lora_scale: Optional[float] = None,
     ):
         r"""
 
@@ -391,9 +396,22 @@ class StableDiffusion3Img2ImgPipeline(DiffusionPipeline):
             clip_skip (`int`, *optional*):
                 Number of layers to be skipped from CLIP while computing the prompt embeddings. A value of 1 means that
                 the output of the pre-final layer will be used for computing the prompt embeddings.
+            lora_scale (`float`, *optional*):
+                A lora scale that will be applied to all LoRA layers of the text encoder if LoRA layers are loaded.
         """
         device = device or self._execution_device
 
+        # set lora scale so that monkey patched LoRA
+        # function of text encoder can correctly access it
+        if lora_scale is not None and isinstance(self, SD3LoraLoaderMixin):
+            self._lora_scale = lora_scale
+
+            # dynamically adjust the LoRA scale
+            if self.text_encoder is not None and USE_PEFT_BACKEND:
+                scale_lora_layers(self.text_encoder, lora_scale)
+            if self.text_encoder_2 is not None and USE_PEFT_BACKEND:
+                scale_lora_layers(self.text_encoder_2, lora_scale)
+
         prompt = [prompt] if isinstance(prompt, str) else prompt
         if prompt is not None:
             batch_size = len(prompt)
@@ -496,6 +514,16 @@ class StableDiffusion3Img2ImgPipeline(DiffusionPipeline):
                 [negative_pooled_prompt_embed, negative_pooled_prompt_2_embed], dim=-1
             )
 
+        if self.text_encoder is not None:
+            if isinstance(self, SD3LoraLoaderMixin) and USE_PEFT_BACKEND:
+                # Retrieve the original scale by scaling back the LoRA layers
+                unscale_lora_layers(self.text_encoder, lora_scale)
+
+        if self.text_encoder_2 is not None:
+            if isinstance(self, SD3LoraLoaderMixin) and USE_PEFT_BACKEND:
+                # Retrieve the original scale by scaling back the LoRA layers
+                unscale_lora_layers(self.text_encoder_2, lora_scale)
+
         return prompt_embeds, negative_prompt_embeds, pooled_prompt_embeds, negative_pooled_prompt_embeds
 
     def check_inputs(

tests/lora/test_lora_layers_sd3.py

@@ -12,377 +12,55 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
-import os
 import sys
-import tempfile
 import unittest
 
-import numpy as np
-import torch
-from transformers import AutoTokenizer, CLIPTextConfig, CLIPTextModelWithProjection, CLIPTokenizer, T5EncoderModel
-
 from diffusers import (
-    AutoencoderKL,
     FlowMatchEulerDiscreteScheduler,
-    SD3Transformer2DModel,
     StableDiffusion3Pipeline,
 )
 from diffusers.utils.testing_utils import is_peft_available, require_peft_backend, require_torch_gpu, torch_device
 
 
 if is_peft_available():
-    from peft import LoraConfig
-    from peft.utils import get_peft_model_state_dict
+    pass
 
 sys.path.append(".")
 
-from utils import check_if_lora_correctly_set  # noqa: E402
+from utils import PeftLoraLoaderMixinTests  # noqa: E402
 
 
 @require_peft_backend
-class SD3LoRATests(unittest.TestCase):
+class SD3LoRATests(unittest.TestCase, PeftLoraLoaderMixinTests):
     pipeline_class = StableDiffusion3Pipeline
-
-    def get_dummy_components(self):
-        torch.manual_seed(0)
-        transformer = SD3Transformer2DModel(
-            sample_size=32,
-            patch_size=1,
-            in_channels=4,
-            num_layers=1,
-            attention_head_dim=8,
-            num_attention_heads=4,
-            caption_projection_dim=32,
-            joint_attention_dim=32,
-            pooled_projection_dim=64,
-            out_channels=4,
-        )
-        clip_text_encoder_config = CLIPTextConfig(
-            bos_token_id=0,
-            eos_token_id=2,
-            hidden_size=32,
-            intermediate_size=37,
-            layer_norm_eps=1e-05,
-            num_attention_heads=4,
-            num_hidden_layers=5,
-            pad_token_id=1,
-            vocab_size=1000,
-            hidden_act="gelu",
-            projection_dim=32,
-        )
-
-        torch.manual_seed(0)
-        text_encoder = CLIPTextModelWithProjection(clip_text_encoder_config)
-
-        torch.manual_seed(0)
-        text_encoder_2 = CLIPTextModelWithProjection(clip_text_encoder_config)
-
-        text_encoder_3 = T5EncoderModel.from_pretrained("hf-internal-testing/tiny-random-t5")
-
-        tokenizer = CLIPTokenizer.from_pretrained("hf-internal-testing/tiny-random-clip")
-        tokenizer_2 = CLIPTokenizer.from_pretrained("hf-internal-testing/tiny-random-clip")
-        tokenizer_3 = AutoTokenizer.from_pretrained("hf-internal-testing/tiny-random-t5")
-
-        torch.manual_seed(0)
-        vae = AutoencoderKL(
-            sample_size=32,
-            in_channels=3,
-            out_channels=3,
-            block_out_channels=(4,),
-            layers_per_block=1,
-            latent_channels=4,
-            norm_num_groups=1,
-            use_quant_conv=False,
-            use_post_quant_conv=False,
-            shift_factor=0.0609,
-            scaling_factor=1.5035,
-        )
-
-        scheduler = FlowMatchEulerDiscreteScheduler()
-
-        return {
-            "scheduler": scheduler,
-            "text_encoder": text_encoder,
-            "text_encoder_2": text_encoder_2,
-            "text_encoder_3": text_encoder_3,
-            "tokenizer": tokenizer,
-            "tokenizer_2": tokenizer_2,
-            "tokenizer_3": tokenizer_3,
-            "transformer": transformer,
-            "vae": vae,
-        }
-
-    def get_dummy_inputs(self, device, seed=0):
-        if str(device).startswith("mps"):
-            generator = torch.manual_seed(seed)
-        else:
-            generator = torch.Generator(device="cpu").manual_seed(seed)
-
-        inputs = {
-            "prompt": "A painting of a squirrel eating a burger",
-            "generator": generator,
-            "num_inference_steps": 2,
-            "guidance_scale": 5.0,
-            "output_type": "np",
-        }
-        return inputs
-
-    def get_lora_config_for_transformer(self):
-        lora_config = LoraConfig(
-            r=4,
-            lora_alpha=4,
-            target_modules=["to_q", "to_k", "to_v", "to_out.0"],
-            init_lora_weights=False,
-            use_dora=False,
-        )
-        return lora_config
-
-    def get_lora_config_for_text_encoders(self):
-        text_lora_config = LoraConfig(
-            r=4,
-            lora_alpha=4,
-            init_lora_weights="gaussian",
-            target_modules=["q_proj", "k_proj", "v_proj", "out_proj"],
-        )
-        return text_lora_config
-
-    def test_simple_inference_with_transformer_lora_save_load(self):
-        components = self.get_dummy_components()
-        transformer_config = self.get_lora_config_for_transformer()
-
-        pipe = self.pipeline_class(**components)
-        pipe = pipe.to(torch_device)
-        pipe.set_progress_bar_config(disable=None)
-        inputs = self.get_dummy_inputs(torch_device)
-
-        pipe.transformer.add_adapter(transformer_config)
-        self.assertTrue(check_if_lora_correctly_set(pipe.transformer), "Lora not correctly set in transformer")
-        inputs = self.get_dummy_inputs(torch_device)
-        images_lora = pipe(**inputs).images
-
-        with tempfile.TemporaryDirectory() as tmpdirname:
-            transformer_state_dict = get_peft_model_state_dict(pipe.transformer)
-
-            self.pipeline_class.save_lora_weights(
-                save_directory=tmpdirname,
-                transformer_lora_layers=transformer_state_dict,
-            )
-
-            self.assertTrue(os.path.isfile(os.path.join(tmpdirname, "pytorch_lora_weights.safetensors")))
-            pipe.unload_lora_weights()
-
-            pipe.load_lora_weights(os.path.join(tmpdirname, "pytorch_lora_weights.safetensors"))
-
-        inputs = self.get_dummy_inputs(torch_device)
-        images_lora_from_pretrained = pipe(**inputs).images
-        self.assertTrue(check_if_lora_correctly_set(pipe.transformer), "Lora not correctly set in transformer")
-
-        self.assertTrue(
-            np.allclose(images_lora, images_lora_from_pretrained, atol=1e-3, rtol=1e-3),
-            "Loading from saved checkpoints should give same results.",
-        )
-
-    def test_simple_inference_with_clip_encoders_lora_save_load(self):
-        components = self.get_dummy_components()
-        transformer_config = self.get_lora_config_for_transformer()
-        text_encoder_config = self.get_lora_config_for_text_encoders()
-
-        pipe = self.pipeline_class(**components)
-        pipe = pipe.to(torch_device)
-        pipe.set_progress_bar_config(disable=None)
-        inputs = self.get_dummy_inputs(torch_device)
-
-        pipe.transformer.add_adapter(transformer_config)
-        pipe.text_encoder.add_adapter(text_encoder_config)
-        pipe.text_encoder_2.add_adapter(text_encoder_config)
-
-        self.assertTrue(check_if_lora_correctly_set(pipe.transformer), "Lora not correctly set in transformer")
-        self.assertTrue(check_if_lora_correctly_set(pipe.text_encoder), "Lora not correctly set in text encoder.")
-        self.assertTrue(check_if_lora_correctly_set(pipe.text_encoder_2), "Lora not correctly set in text encoder 2.")
-
-        inputs = self.get_dummy_inputs(torch_device)
-        images_lora = pipe(**inputs).images
-
-        with tempfile.TemporaryDirectory() as tmpdirname:
-            transformer_state_dict = get_peft_model_state_dict(pipe.transformer)
-            text_encoder_one_state_dict = get_peft_model_state_dict(pipe.text_encoder)
-            text_encoder_two_state_dict = get_peft_model_state_dict(pipe.text_encoder_2)
-
-            self.pipeline_class.save_lora_weights(
-                save_directory=tmpdirname,
-                transformer_lora_layers=transformer_state_dict,
-                text_encoder_lora_layers=text_encoder_one_state_dict,
-                text_encoder_2_lora_layers=text_encoder_two_state_dict,
-            )
-
-            self.assertTrue(os.path.isfile(os.path.join(tmpdirname, "pytorch_lora_weights.safetensors")))
-            pipe.unload_lora_weights()
-
-            pipe.load_lora_weights(os.path.join(tmpdirname, "pytorch_lora_weights.safetensors"))
-
-        inputs = self.get_dummy_inputs(torch_device)
-        images_lora_from_pretrained = pipe(**inputs).images
-        self.assertTrue(check_if_lora_correctly_set(pipe.transformer), "Lora not correctly set in transformer")
-        self.assertTrue(check_if_lora_correctly_set(pipe.text_encoder), "Lora not correctly set in text_encoder_one")
-        self.assertTrue(check_if_lora_correctly_set(pipe.text_encoder_2), "Lora not correctly set in text_encoder_two")
-
-        self.assertTrue(
-            np.allclose(images_lora, images_lora_from_pretrained, atol=1e-3, rtol=1e-3),
-            "Loading from saved checkpoints should give same results.",
-        )
-
-    def test_simple_inference_with_transformer_lora_and_scale(self):
-        components = self.get_dummy_components()
-        transformer_lora_config = self.get_lora_config_for_transformer()
-        pipe = self.pipeline_class(**components)
-        pipe = pipe.to(torch_device)
-        pipe.set_progress_bar_config(disable=None)
-
-        inputs = self.get_dummy_inputs(torch_device)
-        output_no_lora = pipe(**inputs).images
-
-        pipe.transformer.add_adapter(transformer_lora_config)
-        self.assertTrue(check_if_lora_correctly_set(pipe.transformer), "Lora not correctly set in transformer")
-
-        inputs = self.get_dummy_inputs(torch_device)
-        output_lora = pipe(**inputs).images
-        self.assertTrue(
-            not np.allclose(output_lora, output_no_lora, atol=1e-3, rtol=1e-3), "Lora should change the output"
-        )
-
-        inputs = self.get_dummy_inputs(torch_device)
-        output_lora_scale = pipe(**inputs, joint_attention_kwargs={"scale": 0.5}).images
-        self.assertTrue(
-            not np.allclose(output_lora, output_lora_scale, atol=1e-3, rtol=1e-3),
-            "Lora + scale should change the output",
-        )
-
-        inputs = self.get_dummy_inputs(torch_device)
-        output_lora_0_scale = pipe(**inputs, joint_attention_kwargs={"scale": 0.0}).images
-        self.assertTrue(
-            np.allclose(output_no_lora, output_lora_0_scale, atol=1e-3, rtol=1e-3),
-            "Lora + 0 scale should lead to same result as no LoRA",
-        )
-
-    def test_simple_inference_with_clip_encoders_lora_and_scale(self):
-        components = self.get_dummy_components()
-        transformer_lora_config = self.get_lora_config_for_transformer()
-        text_encoder_config = self.get_lora_config_for_text_encoders()
-        pipe = self.pipeline_class(**components)
-        pipe = pipe.to(torch_device)
-        pipe.set_progress_bar_config(disable=None)
-
-        inputs = self.get_dummy_inputs(torch_device)
-        output_no_lora = pipe(**inputs).images
-
-        pipe.transformer.add_adapter(transformer_lora_config)
-        pipe.text_encoder.add_adapter(text_encoder_config)
-        pipe.text_encoder_2.add_adapter(text_encoder_config)
-        self.assertTrue(check_if_lora_correctly_set(pipe.transformer), "Lora not correctly set in transformer")
-        self.assertTrue(check_if_lora_correctly_set(pipe.text_encoder), "Lora not correctly set in text_encoder_one")
-        self.assertTrue(check_if_lora_correctly_set(pipe.text_encoder_2), "Lora not correctly set in text_encoder_two")
-
-        inputs = self.get_dummy_inputs(torch_device)
-        output_lora = pipe(**inputs).images
-        self.assertTrue(
-            not np.allclose(output_lora, output_no_lora, atol=1e-3, rtol=1e-3), "Lora should change the output"
-        )
-
-        inputs = self.get_dummy_inputs(torch_device)
-        output_lora_scale = pipe(**inputs, joint_attention_kwargs={"scale": 0.5}).images
-        self.assertTrue(
-            not np.allclose(output_lora, output_lora_scale, atol=1e-3, rtol=1e-3),
-            "Lora + scale should change the output",
-        )
-
-        inputs = self.get_dummy_inputs(torch_device)
-        output_lora_0_scale = pipe(**inputs, joint_attention_kwargs={"scale": 0.0}).images
-        self.assertTrue(
-            np.allclose(output_no_lora, output_lora_0_scale, atol=1e-3, rtol=1e-3),
-            "Lora + 0 scale should lead to same result as no LoRA",
-        )
-
-    def test_simple_inference_with_transformer_fused(self):
-        components = self.get_dummy_components()
-        transformer_lora_config = self.get_lora_config_for_transformer()
-        pipe = self.pipeline_class(**components)
-        pipe = pipe.to(torch_device)
-        pipe.set_progress_bar_config(disable=None)
-
-        inputs = self.get_dummy_inputs(torch_device)
-        output_no_lora = pipe(**inputs).images
-
-        pipe.transformer.add_adapter(transformer_lora_config)
-        self.assertTrue(check_if_lora_correctly_set(pipe.transformer), "Lora not correctly set in transformer")
-
-        pipe.fuse_lora()
-        # Fusing should still keep the LoRA layers
-        self.assertTrue(check_if_lora_correctly_set(pipe.transformer), "Lora not correctly set in transformer")
-
-        inputs = self.get_dummy_inputs(torch_device)
-        ouput_fused = pipe(**inputs).images
-        self.assertFalse(
-            np.allclose(ouput_fused, output_no_lora, atol=1e-3, rtol=1e-3), "Fused lora should change the output"
-        )
-
-    def test_simple_inference_with_transformer_fused_with_no_fusion(self):
-        components = self.get_dummy_components()
-        transformer_lora_config = self.get_lora_config_for_transformer()
-        pipe = self.pipeline_class(**components)
-        pipe = pipe.to(torch_device)
-        pipe.set_progress_bar_config(disable=None)
-
-        inputs = self.get_dummy_inputs(torch_device)
-        output_no_lora = pipe(**inputs).images
-
-        pipe.transformer.add_adapter(transformer_lora_config)
-        self.assertTrue(check_if_lora_correctly_set(pipe.transformer), "Lora not correctly set in transformer")
-        inputs = self.get_dummy_inputs(torch_device)
-        ouput_lora = pipe(**inputs).images
-
-        pipe.fuse_lora()
-        # Fusing should still keep the LoRA layers
-        self.assertTrue(check_if_lora_correctly_set(pipe.transformer), "Lora not correctly set in transformer")
-
-        inputs = self.get_dummy_inputs(torch_device)
-        ouput_fused = pipe(**inputs).images
-        self.assertFalse(
-            np.allclose(ouput_fused, output_no_lora, atol=1e-3, rtol=1e-3), "Fused lora should change the output"
-        )
-        self.assertTrue(
-            np.allclose(ouput_fused, ouput_lora, atol=1e-3, rtol=1e-3),
-            "Fused lora output should be changed when LoRA isn't fused but still effective.",
-        )
-
-    def test_simple_inference_with_transformer_fuse_unfuse(self):
-        components = self.get_dummy_components()
-        transformer_lora_config = self.get_lora_config_for_transformer()
-        pipe = self.pipeline_class(**components)
-        pipe = pipe.to(torch_device)
-        pipe.set_progress_bar_config(disable=None)
-
-        inputs = self.get_dummy_inputs(torch_device)
-        output_no_lora = pipe(**inputs).images
-
-        pipe.transformer.add_adapter(transformer_lora_config)
-        self.assertTrue(check_if_lora_correctly_set(pipe.transformer), "Lora not correctly set in transformer")
-
-        pipe.fuse_lora()
-        # Fusing should still keep the LoRA layers
-        self.assertTrue(check_if_lora_correctly_set(pipe.transformer), "Lora not correctly set in transformer")
-        inputs = self.get_dummy_inputs(torch_device)
-        ouput_fused = pipe(**inputs).images
-        self.assertFalse(
-            np.allclose(ouput_fused, output_no_lora, atol=1e-3, rtol=1e-3), "Fused lora should change the output"
-        )
-
-        pipe.unfuse_lora()
-        self.assertTrue(check_if_lora_correctly_set(pipe.transformer), "Lora not correctly set in transformer")
-        inputs = self.get_dummy_inputs(torch_device)
-        output_unfused_lora = pipe(**inputs).images
-        self.assertTrue(
-            np.allclose(ouput_fused, output_unfused_lora, atol=1e-3, rtol=1e-3), "Fused lora should change the output"
-        )
+    scheduler_cls = FlowMatchEulerDiscreteScheduler()
+    scheduler_kwargs = {}
+    transformer_kwargs = {
+        "sample_size": 32,
+        "patch_size": 1,
+        "in_channels": 4,
+        "num_layers": 1,
+        "attention_head_dim": 8,
+        "num_attention_heads": 4,
+        "caption_projection_dim": 32,
+        "joint_attention_dim": 32,
+        "pooled_projection_dim": 64,
+        "out_channels": 4,
+    }
+    vae_kwargs = {
+        "sample_size": 32,
+        "in_channels": 3,
+        "out_channels": 3,
+        "block_out_channels": (4,),
+        "layers_per_block": 1,
+        "latent_channels": 4,
+        "norm_num_groups": 1,
+        "use_quant_conv": False,
+        "use_post_quant_conv": False,
+        "shift_factor": 0.0609,
+        "scaling_factor": 1.5035,
+    }
+    has_three_text_encoders = True
 
     @require_torch_gpu
     def test_sd3_lora(self):