lora.py 67.7 KB
Newer Older
1
# Copyright 2024 The HuggingFace Team. All rights reserved.
2
3
4
5
6
7
8
9
10
11
12
13
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# 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.
UmerHA's avatar
UmerHA committed
14
import copy
15
import inspect
16
import os
17
from pathlib import Path
18
19
20
21
22
from typing import Callable, Dict, List, Optional, Union

import safetensors
import torch
from huggingface_hub import model_info
23
from huggingface_hub.constants import HF_HUB_OFFLINE
24
from huggingface_hub.utils import validate_hf_hub_args
25
26
27
28
from packaging import version
from torch import nn

from .. import __version__
29
from ..models.modeling_utils import _LOW_CPU_MEM_USAGE_DEFAULT, load_state_dict
30
31
32
33
34
35
36
37
38
39
from ..utils import (
    USE_PEFT_BACKEND,
    _get_model_file,
    convert_state_dict_to_diffusers,
    convert_state_dict_to_peft,
    convert_unet_state_dict_to_peft,
    delete_adapter_layers,
    get_adapter_name,
    get_peft_kwargs,
    is_accelerate_available,
40
    is_peft_version,
41
42
43
44
45
46
47
    is_transformers_available,
    logging,
    recurse_remove_peft_layers,
    scale_lora_layers,
    set_adapter_layers,
    set_weights_and_activate_adapters,
)
48
from .lora_conversion_utils import _convert_kohya_lora_to_diffusers, _maybe_map_sgm_blocks_to_diffusers
49
50
51


if is_transformers_available():
52
    from transformers import PreTrainedModel
53

54
    from ..models.lora import text_encoder_attn_modules, text_encoder_mlp_modules
55
56
57
58
59
60
61
62

if is_accelerate_available():
    from accelerate.hooks import AlignDevicesHook, CpuOffload, remove_hook_from_module

logger = logging.get_logger(__name__)

TEXT_ENCODER_NAME = "text_encoder"
UNET_NAME = "unet"
Will Berman's avatar
Will Berman committed
63
TRANSFORMER_NAME = "transformer"
64
65
66
67
68
69
70
71
72

LORA_WEIGHT_NAME = "pytorch_lora_weights.bin"
LORA_WEIGHT_NAME_SAFE = "pytorch_lora_weights.safetensors"

LORA_DEPRECATION_MESSAGE = "You are using an old version of LoRA backend. This will be deprecated in the next releases in favor of PEFT make sure to install the latest PEFT and transformers packages in the future."


class LoraLoaderMixin:
    r"""
73
74
    Load LoRA layers into [`UNet2DConditionModel`] and
    [`CLIPTextModel`](https://huggingface.co/docs/transformers/model_doc/clip#transformers.CLIPTextModel).
75
    """
76

77
78
    text_encoder_name = TEXT_ENCODER_NAME
    unet_name = UNET_NAME
Will Berman's avatar
Will Berman committed
79
    transformer_name = TRANSFORMER_NAME
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
    num_fused_loras = 0

    def load_lora_weights(
        self, pretrained_model_name_or_path_or_dict: Union[str, Dict[str, torch.Tensor]], adapter_name=None, **kwargs
    ):
        """
        Load LoRA weights specified in `pretrained_model_name_or_path_or_dict` into `self.unet` and
        `self.text_encoder`.

        All kwargs are forwarded to `self.lora_state_dict`.

        See [`~loaders.LoraLoaderMixin.lora_state_dict`] for more details on how the state dict is loaded.

        See [`~loaders.LoraLoaderMixin.load_lora_into_unet`] for more details on how the state dict is loaded into
        `self.unet`.

        See [`~loaders.LoraLoaderMixin.load_lora_into_text_encoder`] for more details on how the state dict is loaded
        into `self.text_encoder`.

        Parameters:
            pretrained_model_name_or_path_or_dict (`str` or `os.PathLike` or `dict`):
101
                See [`~loaders.LoraLoaderMixin.lora_state_dict`].
102
103
104
            kwargs (`dict`, *optional*):
                See [`~loaders.LoraLoaderMixin.lora_state_dict`].
            adapter_name (`str`, *optional*):
105
106
                Adapter name to be used for referencing the loaded adapter model. If not specified, it will use
                `default_{i}` where i is the total number of adapters being loaded.
107
        """
108
109
110
        if not USE_PEFT_BACKEND:
            raise ValueError("PEFT backend is required for this method.")

111
112
113
114
        # if a dict is passed, copy it instead of modifying it inplace
        if isinstance(pretrained_model_name_or_path_or_dict, dict):
            pretrained_model_name_or_path_or_dict = pretrained_model_name_or_path_or_dict.copy()

115
116
117
        # First, ensure that the checkpoint is a compatible one and can be successfully loaded.
        state_dict, network_alphas = self.lora_state_dict(pretrained_model_name_or_path_or_dict, **kwargs)

118
        is_correct_format = all("lora" in key or "dora_scale" in key for key in state_dict.keys())
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
        if not is_correct_format:
            raise ValueError("Invalid LoRA checkpoint.")

        low_cpu_mem_usage = kwargs.pop("low_cpu_mem_usage", _LOW_CPU_MEM_USAGE_DEFAULT)

        self.load_lora_into_unet(
            state_dict,
            network_alphas=network_alphas,
            unet=getattr(self, self.unet_name) if not hasattr(self, "unet") else self.unet,
            low_cpu_mem_usage=low_cpu_mem_usage,
            adapter_name=adapter_name,
            _pipeline=self,
        )
        self.load_lora_into_text_encoder(
            state_dict,
            network_alphas=network_alphas,
            text_encoder=getattr(self, self.text_encoder_name)
            if not hasattr(self, "text_encoder")
            else self.text_encoder,
            lora_scale=self.lora_scale,
            low_cpu_mem_usage=low_cpu_mem_usage,
            adapter_name=adapter_name,
            _pipeline=self,
        )

    @classmethod
145
    @validate_hf_hub_args
146
147
148
149
150
151
    def lora_state_dict(
        cls,
        pretrained_model_name_or_path_or_dict: Union[str, Dict[str, torch.Tensor]],
        **kwargs,
    ):
        r"""
152
153
154
155
156
157
158
159
160
        Return state dict for lora weights and the network alphas.

        <Tip warning={true}>

        We support loading A1111 formatted LoRA checkpoints in a limited capacity.

        This function is experimental and might change in the future.

        </Tip>
161
162
163
164
165
166
167

        Parameters:
            pretrained_model_name_or_path_or_dict (`str` or `os.PathLike` or `dict`):
                Can be either:

                    - A string, the *model id* (for example `google/ddpm-celebahq-256`) of a pretrained model hosted on
                      the Hub.
168
169
                    - A path to a *directory* (for example `./my_model_directory`) containing the model weights saved
                      with [`ModelMixin.save_pretrained`].
170
171
172
173
174
175
176
177
178
                    - A [torch state
                      dict](https://pytorch.org/tutorials/beginner/saving_loading_models.html#what-is-a-state-dict).

            cache_dir (`Union[str, os.PathLike]`, *optional*):
                Path to a directory where a downloaded pretrained model configuration is cached if the standard cache
                is not used.
            force_download (`bool`, *optional*, defaults to `False`):
                Whether or not to force the (re-)download of the model weights and configuration files, overriding the
                cached versions if they exist.
179
180
181
            resume_download:
                Deprecated and ignored. All downloads are now resumed by default when possible. Will be removed in v1
                of Diffusers.
182
183
184
185
186
187
            proxies (`Dict[str, str]`, *optional*):
                A dictionary of proxy servers to use by protocol or endpoint, for example, `{'http': 'foo.bar:3128',
                'http://hostname': 'foo.bar:4012'}`. The proxies are used on each request.
            local_files_only (`bool`, *optional*, defaults to `False`):
                Whether to only load local model weights and configuration files or not. If set to `True`, the model
                won't be downloaded from the Hub.
188
            token (`str` or *bool*, *optional*):
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
                The token to use as HTTP bearer authorization for remote files. If `True`, the token generated from
                `diffusers-cli login` (stored in `~/.huggingface`) is used.
            revision (`str`, *optional*, defaults to `"main"`):
                The specific model version to use. It can be a branch name, a tag name, a commit id, or any identifier
                allowed by Git.
            subfolder (`str`, *optional*, defaults to `""`):
                The subfolder location of a model file within a larger model repository on the Hub or locally.
            low_cpu_mem_usage (`bool`, *optional*, defaults to `True` if torch version >= 1.9.0 else `False`):
                Speed up model loading only loading the pretrained weights and not initializing the weights. This also
                tries to not use more than 1x model size in CPU memory (including peak memory) while loading the model.
                Only supported for PyTorch >= 1.9.0. If you are using an older version of PyTorch, setting this
                argument to `True` will raise an error.
            mirror (`str`, *optional*):
                Mirror source to resolve accessibility issues if you're downloading a model in China. We do not
                guarantee the timeliness or safety of the source, and you should refer to the mirror site for more
                information.
205

206
207
208
        """
        # Load the main state dict first which has the LoRA layers for either of
        # UNet and text encoder or both.
209
        cache_dir = kwargs.pop("cache_dir", None)
210
        force_download = kwargs.pop("force_download", False)
211
        resume_download = kwargs.pop("resume_download", None)
212
        proxies = kwargs.pop("proxies", None)
213
214
        local_files_only = kwargs.pop("local_files_only", None)
        token = kwargs.pop("token", None)
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
        revision = kwargs.pop("revision", None)
        subfolder = kwargs.pop("subfolder", None)
        weight_name = kwargs.pop("weight_name", None)
        unet_config = kwargs.pop("unet_config", None)
        use_safetensors = kwargs.pop("use_safetensors", None)

        allow_pickle = False
        if use_safetensors is None:
            use_safetensors = True
            allow_pickle = True

        user_agent = {
            "file_type": "attn_procs_weights",
            "framework": "pytorch",
        }

        model_file = None
        if not isinstance(pretrained_model_name_or_path_or_dict, dict):
            # Let's first try to load .safetensors weights
            if (use_safetensors and weight_name is None) or (
                weight_name is not None and weight_name.endswith(".safetensors")
            ):
                try:
                    # Here we're relaxing the loading check to enable more Inference API
                    # friendliness where sometimes, it's not at all possible to automatically
                    # determine `weight_name`.
                    if weight_name is None:
                        weight_name = cls._best_guess_weight_name(
243
244
245
                            pretrained_model_name_or_path_or_dict,
                            file_extension=".safetensors",
                            local_files_only=local_files_only,
246
247
248
249
250
251
252
253
254
                        )
                    model_file = _get_model_file(
                        pretrained_model_name_or_path_or_dict,
                        weights_name=weight_name or LORA_WEIGHT_NAME_SAFE,
                        cache_dir=cache_dir,
                        force_download=force_download,
                        resume_download=resume_download,
                        proxies=proxies,
                        local_files_only=local_files_only,
255
                        token=token,
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
                        revision=revision,
                        subfolder=subfolder,
                        user_agent=user_agent,
                    )
                    state_dict = safetensors.torch.load_file(model_file, device="cpu")
                except (IOError, safetensors.SafetensorError) as e:
                    if not allow_pickle:
                        raise e
                    # try loading non-safetensors weights
                    model_file = None
                    pass

            if model_file is None:
                if weight_name is None:
                    weight_name = cls._best_guess_weight_name(
271
                        pretrained_model_name_or_path_or_dict, file_extension=".bin", local_files_only=local_files_only
272
273
274
275
276
277
278
279
280
                    )
                model_file = _get_model_file(
                    pretrained_model_name_or_path_or_dict,
                    weights_name=weight_name or LORA_WEIGHT_NAME,
                    cache_dir=cache_dir,
                    force_download=force_download,
                    resume_download=resume_download,
                    proxies=proxies,
                    local_files_only=local_files_only,
281
                    token=token,
282
283
284
285
                    revision=revision,
                    subfolder=subfolder,
                    user_agent=user_agent,
                )
286
                state_dict = load_state_dict(model_file)
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
        else:
            state_dict = pretrained_model_name_or_path_or_dict

        network_alphas = None
        # TODO: replace it with a method from `state_dict_utils`
        if all(
            (
                k.startswith("lora_te_")
                or k.startswith("lora_unet_")
                or k.startswith("lora_te1_")
                or k.startswith("lora_te2_")
            )
            for k in state_dict.keys()
        ):
            # Map SDXL blocks correctly.
            if unet_config is not None:
                # use unet config to remap block numbers
304
305
                state_dict = _maybe_map_sgm_blocks_to_diffusers(state_dict, unet_config)
            state_dict, network_alphas = _convert_kohya_lora_to_diffusers(state_dict)
306
307
308
309

        return state_dict, network_alphas

    @classmethod
310
311
312
313
314
315
    def _best_guess_weight_name(
        cls, pretrained_model_name_or_path_or_dict, file_extension=".safetensors", local_files_only=False
    ):
        if local_files_only or HF_HUB_OFFLINE:
            raise ValueError("When using the offline mode, you must specify a `weight_name`.")

316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
        targeted_files = []

        if os.path.isfile(pretrained_model_name_or_path_or_dict):
            return
        elif os.path.isdir(pretrained_model_name_or_path_or_dict):
            targeted_files = [
                f for f in os.listdir(pretrained_model_name_or_path_or_dict) if f.endswith(file_extension)
            ]
        else:
            files_in_repo = model_info(pretrained_model_name_or_path_or_dict).siblings
            targeted_files = [f.rfilename for f in files_in_repo if f.rfilename.endswith(file_extension)]
        if len(targeted_files) == 0:
            return

        # "scheduler" does not correspond to a LoRA checkpoint.
        # "optimizer" does not correspond to a LoRA checkpoint
        # only top-level checkpoints are considered and not the other ones, hence "checkpoint".
        unallowed_substrings = {"scheduler", "optimizer", "checkpoint"}
        targeted_files = list(
            filter(lambda x: all(substring not in x for substring in unallowed_substrings), targeted_files)
        )

        if any(f.endswith(LORA_WEIGHT_NAME) for f in targeted_files):
            targeted_files = list(filter(lambda x: x.endswith(LORA_WEIGHT_NAME), targeted_files))
        elif any(f.endswith(LORA_WEIGHT_NAME_SAFE) for f in targeted_files):
            targeted_files = list(filter(lambda x: x.endswith(LORA_WEIGHT_NAME_SAFE), targeted_files))

        if len(targeted_files) > 1:
            raise ValueError(
                f"Provided path contains more than one weights file in the {file_extension} format. Either specify `weight_name` in `load_lora_weights` or make sure there's only one  `.safetensors` or `.bin` file in  {pretrained_model_name_or_path_or_dict}."
            )
        weight_name = targeted_files[0]
        return weight_name

    @classmethod
    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:
            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:
372
373
374
375
376
                        is_sequential_cpu_offload = (
                            isinstance(component._hf_hook, AlignDevicesHook)
                            or hasattr(component._hf_hook, "hooks")
                            and isinstance(component._hf_hook.hooks[0], AlignDevicesHook)
                        )
377
378
379
380
381
382
383
384
385
386
387
388
389

                    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)

    @classmethod
    def load_lora_into_unet(
        cls, state_dict, network_alphas, unet, low_cpu_mem_usage=None, adapter_name=None, _pipeline=None
    ):
        """
390
        This will load the LoRA layers specified in `state_dict` into `unet`.
391
392
393

        Parameters:
            state_dict (`dict`):
394
395
396
                A standard state dict containing the lora layer parameters. The keys can either be indexed directly
                into the unet or prefixed with an additional `unet` which can be used to distinguish between text
                encoder lora layers.
397
            network_alphas (`Dict[str, float]`):
398
                See `LoRALinearLayer` for more details.
399
400
401
            unet (`UNet2DConditionModel`):
                The UNet model to load the LoRA layers into.
            low_cpu_mem_usage (`bool`, *optional*, defaults to `True` if torch version >= 1.9.0 else `False`):
402
403
404
405
                Speed up model loading only loading the pretrained weights and not initializing the weights. This also
                tries to not use more than 1x model size in CPU memory (including peak memory) while loading the model.
                Only supported for PyTorch >= 1.9.0. If you are using an older version of PyTorch, setting this
                argument to `True` will raise an error.
406
            adapter_name (`str`, *optional*):
407
408
                Adapter name to be used for referencing the loaded adapter model. If not specified, it will use
                `default_{i}` where i is the total number of adapters being loaded.
409
        """
410
411
412
413
414
        if not USE_PEFT_BACKEND:
            raise ValueError("PEFT backend is required for this method.")

        from peft import LoraConfig, inject_adapter_in_model, set_peft_model_state_dict

415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
        low_cpu_mem_usage = low_cpu_mem_usage if low_cpu_mem_usage is not None else _LOW_CPU_MEM_USAGE_DEFAULT
        # If the serialization format is new (introduced in https://github.com/huggingface/diffusers/pull/2918),
        # then the `state_dict` keys should have `cls.unet_name` and/or `cls.text_encoder_name` as
        # their prefixes.
        keys = list(state_dict.keys())

        if all(key.startswith(cls.unet_name) or key.startswith(cls.text_encoder_name) for key in keys):
            # Load the layers corresponding to UNet.
            logger.info(f"Loading {cls.unet_name}.")

            unet_keys = [k for k in keys if k.startswith(cls.unet_name)]
            state_dict = {k.replace(f"{cls.unet_name}.", ""): v for k, v in state_dict.items() if k in unet_keys}

            if network_alphas is not None:
                alpha_keys = [k for k in network_alphas.keys() if k.startswith(cls.unet_name)]
                network_alphas = {
                    k.replace(f"{cls.unet_name}.", ""): v for k, v in network_alphas.items() if k in alpha_keys
                }

        else:
            # Otherwise, we're dealing with the old format. This means the `state_dict` should only
            # contain the module names of the `unet` as its keys WITHOUT any prefix.
437
438
            if not USE_PEFT_BACKEND:
                warn_message = "You have saved the LoRA weights using the old format. To convert the old LoRA weights to the new format, you can first load them in a dictionary and then create a new dictionary like the following: `new_state_dict = {f'unet.{module_name}': params for module_name, params in old_state_dict.items()}`."
439
                logger.warning(warn_message)
440

441
        if len(state_dict.keys()) > 0:
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
            if adapter_name in getattr(unet, "peft_config", {}):
                raise ValueError(
                    f"Adapter name {adapter_name} already in use in the Unet - please select a new adapter name."
                )

            state_dict = convert_unet_state_dict_to_peft(state_dict)

            if network_alphas is not None:
                # The alphas state dict have the same structure as Unet, thus we convert it to peft format using
                # `convert_unet_state_dict_to_peft` method.
                network_alphas = convert_unet_state_dict_to_peft(network_alphas)

            rank = {}
            for key, val in state_dict.items():
                if "lora_B" in key:
                    rank[key] = val.shape[1]

            lora_config_kwargs = get_peft_kwargs(rank, network_alphas, state_dict, is_unet=True)
460
461
462
463
464
465
466
467
468
            if "use_dora" in lora_config_kwargs:
                if lora_config_kwargs["use_dora"]:
                    if is_peft_version("<", "0.9.0"):
                        raise ValueError(
                            "You need `peft` 0.9.0 at least to use DoRA-enabled LoRAs. Please upgrade your installation of `peft`."
                        )
                else:
                    if is_peft_version("<", "0.9.0"):
                        lora_config_kwargs.pop("use_dora")
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
            lora_config = LoraConfig(**lora_config_kwargs)

            # adapter_name
            if adapter_name is None:
                adapter_name = get_adapter_name(unet)

            # In case the pipeline has been already offloaded to CPU - temporarily remove the hooks
            # otherwise loading LoRA weights will lead to an error
            is_model_cpu_offload, is_sequential_cpu_offload = cls._optionally_disable_offloading(_pipeline)

            inject_adapter_in_model(lora_config, unet, adapter_name=adapter_name)
            incompatible_keys = set_peft_model_state_dict(unet, state_dict, adapter_name)

            if incompatible_keys is not None:
                # check only for unexpected keys
                unexpected_keys = getattr(incompatible_keys, "unexpected_keys", None)
                if unexpected_keys:
                    logger.warning(
                        f"Loading adapter weights from state_dict led to unexpected keys not found in the model: "
                        f" {unexpected_keys}. "
                    )

            # Offload back.
            if is_model_cpu_offload:
                _pipeline.enable_model_cpu_offload()
            elif is_sequential_cpu_offload:
                _pipeline.enable_sequential_cpu_offload()
            # Unsafe code />

        unet.load_attn_procs(
            state_dict, network_alphas=network_alphas, low_cpu_mem_usage=low_cpu_mem_usage, _pipeline=_pipeline
        )

    @classmethod
    def load_lora_into_text_encoder(
        cls,
        state_dict,
        network_alphas,
        text_encoder,
        prefix=None,
        lora_scale=1.0,
        low_cpu_mem_usage=None,
        adapter_name=None,
        _pipeline=None,
    ):
        """
515
        This will load the LoRA layers specified in `state_dict` into `text_encoder`
516
517
518

        Parameters:
            state_dict (`dict`):
519
520
                A standard state dict containing the lora layer parameters. The key should be prefixed with an
                additional `text_encoder` to distinguish between unet lora layers.
521
            network_alphas (`Dict[str, float]`):
522
                See `LoRALinearLayer` for more details.
523
524
525
526
527
            text_encoder (`CLIPTextModel`):
                The text encoder model to load the LoRA layers into.
            prefix (`str`):
                Expected prefix of the `text_encoder` in the `state_dict`.
            lora_scale (`float`):
528
529
                How much to scale the output of the lora linear layer before it is added with the output of the regular
                lora layer.
530
            low_cpu_mem_usage (`bool`, *optional*, defaults to `True` if torch version >= 1.9.0 else `False`):
531
532
533
534
                Speed up model loading only loading the pretrained weights and not initializing the weights. This also
                tries to not use more than 1x model size in CPU memory (including peak memory) while loading the model.
                Only supported for PyTorch >= 1.9.0. If you are using an older version of PyTorch, setting this
                argument to `True` will raise an error.
535
536
537
538
            adapter_name (`str`, *optional*):
                Adapter name to be used for referencing the loaded adapter model. If not specified, it will use
                `default_{i}` where i is the total number of adapters being loaded.
        """
539
540
541
542
543
        if not USE_PEFT_BACKEND:
            raise ValueError("PEFT backend is required for this method.")

        from peft import LoraConfig

544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
        low_cpu_mem_usage = low_cpu_mem_usage if low_cpu_mem_usage is not None else _LOW_CPU_MEM_USAGE_DEFAULT

        # If the serialization format is new (introduced in https://github.com/huggingface/diffusers/pull/2918),
        # then the `state_dict` keys should have `self.unet_name` and/or `self.text_encoder_name` as
        # their prefixes.
        keys = list(state_dict.keys())
        prefix = cls.text_encoder_name if prefix is None else prefix

        # Safe prefix to check with.
        if any(cls.text_encoder_name in key for key in keys):
            # Load the layers corresponding to text encoder and make necessary adjustments.
            text_encoder_keys = [k for k in keys if k.startswith(prefix) and k.split(".")[0] == prefix]
            text_encoder_lora_state_dict = {
                k.replace(f"{prefix}.", ""): v for k, v in state_dict.items() if k in text_encoder_keys
            }

            if len(text_encoder_lora_state_dict) > 0:
                logger.info(f"Loading {prefix}.")
                rank = {}
                text_encoder_lora_state_dict = convert_state_dict_to_diffusers(text_encoder_lora_state_dict)

565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
                # convert state dict
                text_encoder_lora_state_dict = convert_state_dict_to_peft(text_encoder_lora_state_dict)

                for name, _ in text_encoder_attn_modules(text_encoder):
                    rank_key = f"{name}.out_proj.lora_B.weight"
                    rank[rank_key] = text_encoder_lora_state_dict[rank_key].shape[1]

                patch_mlp = any(".mlp." in key for key in text_encoder_lora_state_dict.keys())
                if patch_mlp:
                    for name, _ in text_encoder_mlp_modules(text_encoder):
                        rank_key_fc1 = f"{name}.fc1.lora_B.weight"
                        rank_key_fc2 = f"{name}.fc2.lora_B.weight"

                        rank[rank_key_fc1] = text_encoder_lora_state_dict[rank_key_fc1].shape[1]
                        rank[rank_key_fc2] = text_encoder_lora_state_dict[rank_key_fc2].shape[1]
580
581
582
583
584
585
586
587
588

                if network_alphas is not None:
                    alpha_keys = [
                        k for k in network_alphas.keys() if k.startswith(prefix) and k.split(".")[0] == prefix
                    ]
                    network_alphas = {
                        k.replace(f"{prefix}.", ""): v for k, v in network_alphas.items() if k in alpha_keys
                    }

589
                lora_config_kwargs = get_peft_kwargs(rank, network_alphas, text_encoder_lora_state_dict, is_unet=False)
590
591
592
593
594
595
596
597
598
                if "use_dora" in lora_config_kwargs:
                    if lora_config_kwargs["use_dora"]:
                        if is_peft_version("<", "0.9.0"):
                            raise ValueError(
                                "You need `peft` 0.9.0 at least to use DoRA-enabled LoRAs. Please upgrade your installation of `peft`."
                            )
                    else:
                        if is_peft_version("<", "0.9.0"):
                            lora_config_kwargs.pop("use_dora")
599
                lora_config = LoraConfig(**lora_config_kwargs)
600

601
602
603
                # adapter_name
                if adapter_name is None:
                    adapter_name = get_adapter_name(text_encoder)
604

605
                is_model_cpu_offload, is_sequential_cpu_offload = cls._optionally_disable_offloading(_pipeline)
606

607
608
609
610
611
612
613
                # inject LoRA layers and load the state dict
                # in transformers we automatically check whether the adapter name is already in use or not
                text_encoder.load_adapter(
                    adapter_name=adapter_name,
                    adapter_state_dict=text_encoder_lora_state_dict,
                    peft_config=lora_config,
                )
614

615
616
                # scale LoRA layers with `lora_scale`
                scale_lora_layers(text_encoder, weight=lora_scale)
617
618
619
620
621
622
623
624
625
626

                text_encoder.to(device=text_encoder.device, dtype=text_encoder.dtype)

                # Offload back.
                if is_model_cpu_offload:
                    _pipeline.enable_model_cpu_offload()
                elif is_sequential_cpu_offload:
                    _pipeline.enable_sequential_cpu_offload()
                # Unsafe code />

Will Berman's avatar
Will Berman committed
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
    @classmethod
    def load_lora_into_transformer(
        cls, state_dict, network_alphas, transformer, low_cpu_mem_usage=None, adapter_name=None, _pipeline=None
    ):
        """
        This will load the LoRA layers specified in `state_dict` into `transformer`.

        Parameters:
            state_dict (`dict`):
                A standard state dict containing the lora layer parameters. The keys can either be indexed directly
                into the unet or prefixed with an additional `unet` which can be used to distinguish between text
                encoder lora layers.
            network_alphas (`Dict[str, float]`):
                See `LoRALinearLayer` for more details.
            unet (`UNet2DConditionModel`):
                The UNet model to load the LoRA layers into.
            low_cpu_mem_usage (`bool`, *optional*, defaults to `True` if torch version >= 1.9.0 else `False`):
                Speed up model loading only loading the pretrained weights and not initializing the weights. This also
                tries to not use more than 1x model size in CPU memory (including peak memory) while loading the model.
                Only supported for PyTorch >= 1.9.0. If you are using an older version of PyTorch, setting this
                argument to `True` will raise an error.
            adapter_name (`str`, *optional*):
                Adapter name to be used for referencing the loaded adapter model. If not specified, it will use
                `default_{i}` where i is the total number of adapters being loaded.
        """
652
653
        from peft import LoraConfig, inject_adapter_in_model, set_peft_model_state_dict

Will Berman's avatar
Will Berman committed
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
        low_cpu_mem_usage = low_cpu_mem_usage if low_cpu_mem_usage is not None else _LOW_CPU_MEM_USAGE_DEFAULT

        keys = list(state_dict.keys())

        transformer_keys = [k for k in keys if k.startswith(cls.transformer_name)]
        state_dict = {
            k.replace(f"{cls.transformer_name}.", ""): v for k, v in state_dict.items() if k in transformer_keys
        }

        if network_alphas is not None:
            alpha_keys = [k for k in network_alphas.keys() if k.startswith(cls.transformer_name)]
            network_alphas = {
                k.replace(f"{cls.transformer_name}.", ""): v for k, v in network_alphas.items() if k in alpha_keys
            }

        if len(state_dict.keys()) > 0:
            if adapter_name in getattr(transformer, "peft_config", {}):
                raise ValueError(
                    f"Adapter name {adapter_name} already in use in the transformer - please select a new adapter name."
                )

            rank = {}
            for key, val in state_dict.items():
                if "lora_B" in key:
                    rank[key] = val.shape[1]

            lora_config_kwargs = get_peft_kwargs(rank, network_alphas, state_dict)
681
682
683
684
685
686
687
            if "use_dora" in lora_config_kwargs:
                if lora_config_kwargs["use_dora"] and is_peft_version("<", "0.9.0"):
                    raise ValueError(
                        "You need `peft` 0.9.0 at least to use DoRA-enabled LoRAs. Please upgrade your installation of `peft`."
                    )
                else:
                    lora_config_kwargs.pop("use_dora")
Will Berman's avatar
Will Berman committed
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
            lora_config = LoraConfig(**lora_config_kwargs)

            # adapter_name
            if adapter_name is None:
                adapter_name = get_adapter_name(transformer)

            # In case the pipeline has been already offloaded to CPU - temporarily remove the hooks
            # otherwise loading LoRA weights will lead to an error
            is_model_cpu_offload, is_sequential_cpu_offload = cls._optionally_disable_offloading(_pipeline)

            inject_adapter_in_model(lora_config, transformer, adapter_name=adapter_name)
            incompatible_keys = set_peft_model_state_dict(transformer, state_dict, adapter_name)

            if incompatible_keys is not None:
                # check only for unexpected keys
                unexpected_keys = getattr(incompatible_keys, "unexpected_keys", None)
                if unexpected_keys:
                    logger.warning(
                        f"Loading adapter weights from state_dict led to unexpected keys not found in the model: "
                        f" {unexpected_keys}. "
                    )

            # Offload back.
            if is_model_cpu_offload:
                _pipeline.enable_model_cpu_offload()
            elif is_sequential_cpu_offload:
                _pipeline.enable_sequential_cpu_offload()
            # Unsafe code />

717
718
719
720
721
722
723
    @property
    def lora_scale(self) -> float:
        # property function that returns the lora scale which can be set at run time by the pipeline.
        # if _lora_scale has not been set, return 1
        return self._lora_scale if hasattr(self, "_lora_scale") else 1.0

    def _remove_text_encoder_monkey_patch(self):
724
        remove_method = recurse_remove_peft_layers
725
726
727
        if hasattr(self, "text_encoder"):
            remove_method(self.text_encoder)
            # In case text encoder have no Lora attached
728
            if getattr(self.text_encoder, "peft_config", None) is not None:
729
730
                del self.text_encoder.peft_config
                self.text_encoder._hf_peft_config_loaded = None
731

732
733
        if hasattr(self, "text_encoder_2"):
            remove_method(self.text_encoder_2)
734
            if getattr(self.text_encoder_2, "peft_config", None) is not None:
735
736
737
738
739
740
741
742
743
                del self.text_encoder_2.peft_config
                self.text_encoder_2._hf_peft_config_loaded = None

    @classmethod
    def save_lora_weights(
        cls,
        save_directory: Union[str, os.PathLike],
        unet_lora_layers: Dict[str, Union[torch.nn.Module, torch.Tensor]] = None,
        text_encoder_lora_layers: Dict[str, torch.nn.Module] = None,
Will Berman's avatar
Will Berman committed
744
        transformer_lora_layers: Dict[str, torch.nn.Module] = None,
745
746
747
748
749
750
        is_main_process: bool = True,
        weight_name: str = None,
        save_function: Callable = None,
        safe_serialization: bool = True,
    ):
        r"""
751
        Save the LoRA parameters corresponding to the UNet and text encoder.
752
753
754

        Arguments:
            save_directory (`str` or `os.PathLike`):
755
                Directory to save LoRA parameters to. Will be created if it doesn't exist.
756
757
758
759
760
761
762
763
764
765
            unet_lora_layers (`Dict[str, torch.nn.Module]` or `Dict[str, torch.Tensor]`):
                State dict of the LoRA layers corresponding to the `unet`.
            text_encoder_lora_layers (`Dict[str, torch.nn.Module]` or `Dict[str, torch.Tensor]`):
                State dict of the LoRA layers corresponding to the `text_encoder`. Must explicitly pass the text
                encoder LoRA state dict because it comes from 🤗 Transformers.
            is_main_process (`bool`, *optional*, defaults to `True`):
                Whether the process calling this is the main process or not. Useful during distributed training and you
                need to call this function on all processes. In this case, set `is_main_process=True` only on the main
                process to avoid race conditions.
            save_function (`Callable`):
766
767
                The function to use to save the state dictionary. Useful during distributed training when you need to
                replace `torch.save` with another method. Can be configured with the environment variable
768
769
                `DIFFUSERS_SAVE_MODE`.
            safe_serialization (`bool`, *optional*, defaults to `True`):
770
                Whether to save the model using `safetensors` or the traditional PyTorch way with `pickle`.
771
772
773
        """
        state_dict = {}

774
775
776
777
        def pack_weights(layers, prefix):
            layers_weights = layers.state_dict() if isinstance(layers, torch.nn.Module) else layers
            layers_state_dict = {f"{prefix}.{module_name}": param for module_name, param in layers_weights.items()}
            return layers_state_dict
778

Will Berman's avatar
Will Berman committed
779
780
781
782
        if not (unet_lora_layers or text_encoder_lora_layers or transformer_lora_layers):
            raise ValueError(
                "You must pass at least one of `unet_lora_layers`, `text_encoder_lora_layers`, or `transformer_lora_layers`."
            )
783

784
        if unet_lora_layers:
785
            state_dict.update(pack_weights(unet_lora_layers, cls.unet_name))
786

787
        if text_encoder_lora_layers:
788
            state_dict.update(pack_weights(text_encoder_lora_layers, cls.text_encoder_name))
789

Will Berman's avatar
Will Berman committed
790
791
792
        if transformer_lora_layers:
            state_dict.update(pack_weights(transformer_lora_layers, "transformer"))

793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
        # Save the model
        cls.write_lora_layers(
            state_dict=state_dict,
            save_directory=save_directory,
            is_main_process=is_main_process,
            weight_name=weight_name,
            save_function=save_function,
            safe_serialization=safe_serialization,
        )

    @staticmethod
    def write_lora_layers(
        state_dict: Dict[str, torch.Tensor],
        save_directory: str,
        is_main_process: bool,
        weight_name: str,
        save_function: Callable,
        safe_serialization: bool,
    ):
        if os.path.isfile(save_directory):
            logger.error(f"Provided path ({save_directory}) should be a directory, not a file")
            return

        if save_function is None:
            if safe_serialization:

                def save_function(weights, filename):
                    return safetensors.torch.save_file(weights, filename, metadata={"format": "pt"})

            else:
                save_function = torch.save

        os.makedirs(save_directory, exist_ok=True)

        if weight_name is None:
            if safe_serialization:
                weight_name = LORA_WEIGHT_NAME_SAFE
            else:
                weight_name = LORA_WEIGHT_NAME

833
834
835
        save_path = Path(save_directory, weight_name).as_posix()
        save_function(state_dict, save_path)
        logger.info(f"Model weights saved in {save_path}")
836
837
838

    def unload_lora_weights(self):
        """
839
        Unloads the LoRA parameters.
840
841
842

        Examples:

843
844
845
846
        ```python
        >>> # Assuming `pipeline` is already loaded with the LoRA parameters.
        >>> pipeline.unload_lora_weights()
        >>> ...
847
848
        ```
        """
849
850
        unet = getattr(self, self.unet_name) if not hasattr(self, "unet") else self.unet

851
852
        if not USE_PEFT_BACKEND:
            if version.parse(__version__) > version.parse("0.23"):
853
                logger.warning(
854
855
856
857
                    "You are using `unload_lora_weights` to disable and unload lora weights. If you want to iteratively enable and disable adapter weights,"
                    "you can use `pipe.enable_lora()` or `pipe.disable_lora()`. After installing the latest version of PEFT."
                )

858
            for _, module in unet.named_modules():
859
860
861
                if hasattr(module, "set_lora_layer"):
                    module.set_lora_layer(None)
        else:
862
863
864
            recurse_remove_peft_layers(unet)
            if hasattr(unet, "peft_config"):
                del unet.peft_config
865
866
867
868
869
870
871
872
873
874

        # Safe to call the following regardless of LoRA.
        self._remove_text_encoder_monkey_patch()

    def fuse_lora(
        self,
        fuse_unet: bool = True,
        fuse_text_encoder: bool = True,
        lora_scale: float = 1.0,
        safe_fusing: bool = False,
875
        adapter_names: Optional[List[str]] = None,
876
877
    ):
        r"""
878
        Fuses the LoRA parameters into the original parameters of the corresponding blocks.
879
880
881
882
883
884
885
886
887
888
889
890
891

        <Tip warning={true}>

        This is an experimental API.

        </Tip>

        Args:
            fuse_unet (`bool`, defaults to `True`): Whether to fuse the UNet LoRA parameters.
            fuse_text_encoder (`bool`, defaults to `True`):
                Whether to fuse the text encoder LoRA parameters. If the text encoder wasn't monkey-patched with the
                LoRA parameters then it won't have any effect.
            lora_scale (`float`, defaults to 1.0):
892
                Controls how much to influence the outputs with the LoRA parameters.
893
            safe_fusing (`bool`, defaults to `False`):
894
                Whether to check fused weights for NaN values before fusing and if values are NaN not fusing them.
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
            adapter_names (`List[str]`, *optional*):
                Adapter names to be used for fusing. If nothing is passed, all active adapters will be fused.

        Example:

        ```py
        from diffusers import DiffusionPipeline
        import torch

        pipeline = DiffusionPipeline.from_pretrained(
            "stabilityai/stable-diffusion-xl-base-1.0", torch_dtype=torch.float16
        ).to("cuda")
        pipeline.load_lora_weights("nerijs/pixel-art-xl", weight_name="pixel-art-xl.safetensors", adapter_name="pixel")
        pipeline.fuse_lora(lora_scale=0.7)
        ```
910
        """
911
912
        from peft.tuners.tuners_utils import BaseTunerLayer

913
914
915
        if fuse_unet or fuse_text_encoder:
            self.num_fused_loras += 1
            if self.num_fused_loras > 1:
916
                logger.warning(
917
918
919
920
                    "The current API is supported for operating with a single LoRA file. You are trying to load and fuse more than one LoRA which is not well-supported.",
                )

        if fuse_unet:
921
            unet = getattr(self, self.unet_name) if not hasattr(self, "unet") else self.unet
922
            unet.fuse_lora(lora_scale, safe_fusing=safe_fusing, adapter_names=adapter_names)
923

924
925
        def fuse_text_encoder_lora(text_encoder, lora_scale=1.0, safe_fusing=False, adapter_names=None):
            merge_kwargs = {"safe_merge": safe_fusing}
926

927
928
929
930
            for module in text_encoder.modules():
                if isinstance(module, BaseTunerLayer):
                    if lora_scale != 1.0:
                        module.scale_layer(lora_scale)
931

932
933
934
935
936
937
938
939
940
941
                    # For BC with previous 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`"
                        )
942

943
                    module.merge(**merge_kwargs)
944
945
946

        if fuse_text_encoder:
            if hasattr(self, "text_encoder"):
947
                fuse_text_encoder_lora(self.text_encoder, lora_scale, safe_fusing, adapter_names=adapter_names)
948
            if hasattr(self, "text_encoder_2"):
949
                fuse_text_encoder_lora(self.text_encoder_2, lora_scale, safe_fusing, adapter_names=adapter_names)
950
951
952

    def unfuse_lora(self, unfuse_unet: bool = True, unfuse_text_encoder: bool = True):
        r"""
953
954
        Reverses the effect of
        [`pipe.fuse_lora()`](https://huggingface.co/docs/diffusers/main/en/api/loaders#diffusers.loaders.LoraLoaderMixin.fuse_lora).
955
956
957
958
959
960
961
962
963
964
965
966
967

        <Tip warning={true}>

        This is an experimental API.

        </Tip>

        Args:
            unfuse_unet (`bool`, defaults to `True`): Whether to unfuse the UNet LoRA parameters.
            unfuse_text_encoder (`bool`, defaults to `True`):
                Whether to unfuse the text encoder LoRA parameters. If the text encoder wasn't monkey-patched with the
                LoRA parameters then it won't have any effect.
        """
968
969
        from peft.tuners.tuners_utils import BaseTunerLayer

970
        unet = getattr(self, self.unet_name) if not hasattr(self, "unet") else self.unet
971
        if unfuse_unet:
972
973
974
            for module in unet.modules():
                if isinstance(module, BaseTunerLayer):
                    module.unmerge()
975

976
977
978
979
        def unfuse_text_encoder_lora(text_encoder):
            for module in text_encoder.modules():
                if isinstance(module, BaseTunerLayer):
                    module.unmerge()
980
981
982
983
984
985
986
987
988
989
990
991
992

        if unfuse_text_encoder:
            if hasattr(self, "text_encoder"):
                unfuse_text_encoder_lora(self.text_encoder)
            if hasattr(self, "text_encoder_2"):
                unfuse_text_encoder_lora(self.text_encoder_2)

        self.num_fused_loras -= 1

    def set_adapters_for_text_encoder(
        self,
        adapter_names: Union[List[str], str],
        text_encoder: Optional["PreTrainedModel"] = None,  # noqa: F821
UmerHA's avatar
UmerHA committed
993
        text_encoder_weights: Optional[Union[float, List[float], List[None]]] = None,
994
995
    ):
        """
996
        Sets the adapter layers for the text encoder.
997
998
999

        Args:
            adapter_names (`List[str]` or `str`):
1000
                The names of the adapters to use.
1001
            text_encoder (`torch.nn.Module`, *optional*):
1002
1003
                The text encoder module to set the adapter layers for. If `None`, it will try to get the `text_encoder`
                attribute.
1004
1005
1006
1007
1008
1009
1010
            text_encoder_weights (`List[float]`, *optional*):
                The weights to use for the text encoder. If `None`, the weights are set to `1.0` for all the adapters.
        """
        if not USE_PEFT_BACKEND:
            raise ValueError("PEFT backend is required for this method.")

        def process_weights(adapter_names, weights):
UmerHA's avatar
UmerHA committed
1011
1012
1013
1014
            # Expand weights into a list, one entry per adapter
            # e.g. for 2 adapters:  7 -> [7,7] ; [3, None] -> [3, None]
            if not isinstance(weights, list):
                weights = [weights] * len(adapter_names)
1015
1016
1017
1018
1019

            if len(adapter_names) != len(weights):
                raise ValueError(
                    f"Length of adapter names {len(adapter_names)} is not equal to the length of the weights {len(weights)}"
                )
UmerHA's avatar
UmerHA committed
1020
1021
1022
1023
1024

            # Set None values to default of 1.0
            # e.g. [7,7] -> [7,7] ; [3, None] -> [3,1]
            weights = [w if w is not None else 1.0 for w in weights]

1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
            return weights

        adapter_names = [adapter_names] if isinstance(adapter_names, str) else adapter_names
        text_encoder_weights = process_weights(adapter_names, text_encoder_weights)
        text_encoder = text_encoder or getattr(self, "text_encoder", None)
        if text_encoder is None:
            raise ValueError(
                "The pipeline does not have a default `pipe.text_encoder` class. Please make sure to pass a `text_encoder` instead."
            )
        set_weights_and_activate_adapters(text_encoder, adapter_names, text_encoder_weights)

1036
    def disable_lora_for_text_encoder(self, text_encoder: Optional["PreTrainedModel"] = None):
1037
        """
1038
        Disables the LoRA layers for the text encoder.
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052

        Args:
            text_encoder (`torch.nn.Module`, *optional*):
                The text encoder module to disable the LoRA layers for. If `None`, it will try to get the
                `text_encoder` attribute.
        """
        if not USE_PEFT_BACKEND:
            raise ValueError("PEFT backend is required for this method.")

        text_encoder = text_encoder or getattr(self, "text_encoder", None)
        if text_encoder is None:
            raise ValueError("Text Encoder not found.")
        set_adapter_layers(text_encoder, enabled=False)

1053
    def enable_lora_for_text_encoder(self, text_encoder: Optional["PreTrainedModel"] = None):
1054
        """
1055
        Enables the LoRA layers for the text encoder.
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071

        Args:
            text_encoder (`torch.nn.Module`, *optional*):
                The text encoder module to enable the LoRA layers for. If `None`, it will try to get the `text_encoder`
                attribute.
        """
        if not USE_PEFT_BACKEND:
            raise ValueError("PEFT backend is required for this method.")
        text_encoder = text_encoder or getattr(self, "text_encoder", None)
        if text_encoder is None:
            raise ValueError("Text Encoder not found.")
        set_adapter_layers(self.text_encoder, enabled=True)

    def set_adapters(
        self,
        adapter_names: Union[List[str], str],
UmerHA's avatar
UmerHA committed
1072
        adapter_weights: Optional[Union[float, Dict, List[float], List[Dict]]] = None,
1073
    ):
UmerHA's avatar
UmerHA committed
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
        adapter_names = [adapter_names] if isinstance(adapter_names, str) else adapter_names

        adapter_weights = copy.deepcopy(adapter_weights)

        # Expand weights into a list, one entry per adapter
        if not isinstance(adapter_weights, list):
            adapter_weights = [adapter_weights] * len(adapter_names)

        if len(adapter_names) != len(adapter_weights):
            raise ValueError(
                f"Length of adapter names {len(adapter_names)} is not equal to the length of the weights {len(adapter_weights)}"
            )

        # Decompose weights into weights for unet, text_encoder and text_encoder_2
        unet_lora_weights, text_encoder_lora_weights, text_encoder_2_lora_weights = [], [], []

        list_adapters = self.get_list_adapters()  # eg {"unet": ["adapter1", "adapter2"], "text_encoder": ["adapter2"]}
        all_adapters = {
            adapter for adapters in list_adapters.values() for adapter in adapters
        }  # eg ["adapter1", "adapter2"]
        invert_list_adapters = {
            adapter: [part for part, adapters in list_adapters.items() if adapter in adapters]
            for adapter in all_adapters
        }  # eg {"adapter1": ["unet"], "adapter2": ["unet", "text_encoder"]}

        for adapter_name, weights in zip(adapter_names, adapter_weights):
            if isinstance(weights, dict):
                unet_lora_weight = weights.pop("unet", None)
                text_encoder_lora_weight = weights.pop("text_encoder", None)
                text_encoder_2_lora_weight = weights.pop("text_encoder_2", None)

                if len(weights) > 0:
                    raise ValueError(
                        f"Got invalid key '{weights.keys()}' in lora weight dict for adapter {adapter_name}."
                    )

                if text_encoder_2_lora_weight is not None and not hasattr(self, "text_encoder_2"):
                    logger.warning(
                        "Lora weight dict contains text_encoder_2 weights but will be ignored because pipeline does not have text_encoder_2."
                    )

                # warn if adapter doesn't have parts specified by adapter_weights
                for part_weight, part_name in zip(
                    [unet_lora_weight, text_encoder_lora_weight, text_encoder_2_lora_weight],
1118
                    ["unet", "text_encoder", "text_encoder_2"],
UmerHA's avatar
UmerHA committed
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
                ):
                    if part_weight is not None and part_name not in invert_list_adapters[adapter_name]:
                        logger.warning(
                            f"Lora weight dict for adapter '{adapter_name}' contains {part_name}, but this will be ignored because {adapter_name} does not contain weights for {part_name}. Valid parts for {adapter_name} are: {invert_list_adapters[adapter_name]}."
                        )

            else:
                unet_lora_weight = weights
                text_encoder_lora_weight = weights
                text_encoder_2_lora_weight = weights

            unet_lora_weights.append(unet_lora_weight)
            text_encoder_lora_weights.append(text_encoder_lora_weight)
            text_encoder_2_lora_weights.append(text_encoder_2_lora_weight)

1134
        unet = getattr(self, self.unet_name) if not hasattr(self, "unet") else self.unet
1135
        # Handle the UNET
UmerHA's avatar
UmerHA committed
1136
        unet.set_adapters(adapter_names, unet_lora_weights)
1137
1138
1139

        # Handle the Text Encoder
        if hasattr(self, "text_encoder"):
UmerHA's avatar
UmerHA committed
1140
            self.set_adapters_for_text_encoder(adapter_names, self.text_encoder, text_encoder_lora_weights)
1141
        if hasattr(self, "text_encoder_2"):
UmerHA's avatar
UmerHA committed
1142
            self.set_adapters_for_text_encoder(adapter_names, self.text_encoder_2, text_encoder_2_lora_weights)
1143
1144
1145
1146
1147
1148

    def disable_lora(self):
        if not USE_PEFT_BACKEND:
            raise ValueError("PEFT backend is required for this method.")

        # Disable unet adapters
1149
1150
        unet = getattr(self, self.unet_name) if not hasattr(self, "unet") else self.unet
        unet.disable_lora()
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162

        # Disable text encoder adapters
        if hasattr(self, "text_encoder"):
            self.disable_lora_for_text_encoder(self.text_encoder)
        if hasattr(self, "text_encoder_2"):
            self.disable_lora_for_text_encoder(self.text_encoder_2)

    def enable_lora(self):
        if not USE_PEFT_BACKEND:
            raise ValueError("PEFT backend is required for this method.")

        # Enable unet adapters
1163
1164
        unet = getattr(self, self.unet_name) if not hasattr(self, "unet") else self.unet
        unet.enable_lora()
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174

        # Enable text encoder adapters
        if hasattr(self, "text_encoder"):
            self.enable_lora_for_text_encoder(self.text_encoder)
        if hasattr(self, "text_encoder_2"):
            self.enable_lora_for_text_encoder(self.text_encoder_2)

    def delete_adapters(self, adapter_names: Union[List[str], str]):
        """
        Args:
1175
        Deletes the LoRA layers of `adapter_name` for the unet and text-encoder(s).
1176
            adapter_names (`Union[List[str], str]`):
1177
                The names of the adapter to delete. Can be a single string or a list of strings
1178
1179
1180
1181
1182
1183
1184
1185
        """
        if not USE_PEFT_BACKEND:
            raise ValueError("PEFT backend is required for this method.")

        if isinstance(adapter_names, str):
            adapter_names = [adapter_names]

        # Delete unet adapters
1186
1187
        unet = getattr(self, self.unet_name) if not hasattr(self, "unet") else self.unet
        unet.delete_adapters(adapter_names)
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197

        for adapter_name in adapter_names:
            # Delete text encoder adapters
            if hasattr(self, "text_encoder"):
                delete_adapter_layers(self.text_encoder, adapter_name)
            if hasattr(self, "text_encoder_2"):
                delete_adapter_layers(self.text_encoder_2, adapter_name)

    def get_active_adapters(self) -> List[str]:
        """
1198
        Gets the list of the current active adapters.
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219

        Example:

        ```python
        from diffusers import DiffusionPipeline

        pipeline = DiffusionPipeline.from_pretrained(
            "stabilityai/stable-diffusion-xl-base-1.0",
        ).to("cuda")
        pipeline.load_lora_weights("CiroN2022/toy-face", weight_name="toy_face_sdxl.safetensors", adapter_name="toy")
        pipeline.get_active_adapters()
        ```
        """
        if not USE_PEFT_BACKEND:
            raise ValueError(
                "PEFT backend is required for this method. Please install the latest version of PEFT `pip install -U peft`"
            )

        from peft.tuners.tuners_utils import BaseTunerLayer

        active_adapters = []
1220
1221
        unet = getattr(self, self.unet_name) if not hasattr(self, "unet") else self.unet
        for module in unet.modules():
1222
1223
1224
1225
1226
1227
1228
1229
            if isinstance(module, BaseTunerLayer):
                active_adapters = module.active_adapters
                break

        return active_adapters

    def get_list_adapters(self) -> Dict[str, List[str]]:
        """
1230
        Gets the current list of all available adapters in the pipeline.
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
        """
        if not USE_PEFT_BACKEND:
            raise ValueError(
                "PEFT backend is required for this method. Please install the latest version of PEFT `pip install -U peft`"
            )

        set_adapters = {}

        if hasattr(self, "text_encoder") and hasattr(self.text_encoder, "peft_config"):
            set_adapters["text_encoder"] = list(self.text_encoder.peft_config.keys())

        if hasattr(self, "text_encoder_2") and hasattr(self.text_encoder_2, "peft_config"):
            set_adapters["text_encoder_2"] = list(self.text_encoder_2.peft_config.keys())

1245
1246
1247
        unet = getattr(self, self.unet_name) if not hasattr(self, "unet") else self.unet
        if hasattr(self, self.unet_name) and hasattr(unet, "peft_config"):
            set_adapters[self.unet_name] = list(self.unet.peft_config.keys())
1248
1249
1250
1251
1252

        return set_adapters

    def set_lora_device(self, adapter_names: List[str], device: Union[torch.device, str, int]) -> None:
        """
1253
1254
        Moves the LoRAs listed in `adapter_names` to a target device. Useful for offloading the LoRA to the CPU in case
        you want to load multiple adapters and free some GPU memory.
1255
1256
1257

        Args:
            adapter_names (`List[str]`):
1258
                List of adapters to send device to.
1259
            device (`Union[torch.device, str, int]`):
1260
                Device to send the adapters to. Can be either a torch device, a str or an integer.
1261
1262
1263
1264
1265
1266
1267
        """
        if not USE_PEFT_BACKEND:
            raise ValueError("PEFT backend is required for this method.")

        from peft.tuners.tuners_utils import BaseTunerLayer

        # Handle the UNET
1268
1269
        unet = getattr(self, self.unet_name) if not hasattr(self, "unet") else self.unet
        for unet_module in unet.modules():
1270
1271
1272
1273
            if isinstance(unet_module, BaseTunerLayer):
                for adapter_name in adapter_names:
                    unet_module.lora_A[adapter_name].to(device)
                    unet_module.lora_B[adapter_name].to(device)
1274
                    # this is a param, not a module, so device placement is not in-place -> re-assign
Sayak Paul's avatar
Sayak Paul committed
1275
1276
1277
1278
                    if hasattr(unet_module, "lora_magnitude_vector") and unet_module.lora_magnitude_vector is not None:
                        unet_module.lora_magnitude_vector[adapter_name] = unet_module.lora_magnitude_vector[
                            adapter_name
                        ].to(device)
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294

        # Handle the text encoder
        modules_to_process = []
        if hasattr(self, "text_encoder"):
            modules_to_process.append(self.text_encoder)

        if hasattr(self, "text_encoder_2"):
            modules_to_process.append(self.text_encoder_2)

        for text_encoder in modules_to_process:
            # loop over submodules
            for text_encoder_module in text_encoder.modules():
                if isinstance(text_encoder_module, BaseTunerLayer):
                    for adapter_name in adapter_names:
                        text_encoder_module.lora_A[adapter_name].to(device)
                        text_encoder_module.lora_B[adapter_name].to(device)
1295
                        # this is a param, not a module, so device placement is not in-place -> re-assign
Sayak Paul's avatar
Sayak Paul committed
1296
                        if (
1297
                            hasattr(text_encoder_module, "lora_magnitude_vector")
Sayak Paul's avatar
Sayak Paul committed
1298
1299
1300
1301
1302
                            and text_encoder_module.lora_magnitude_vector is not None
                        ):
                            text_encoder_module.lora_magnitude_vector[
                                adapter_name
                            ] = text_encoder_module.lora_magnitude_vector[adapter_name].to(device)
1303
1304
1305


class StableDiffusionXLLoraLoaderMixin(LoraLoaderMixin):
1306
    """This class overrides `LoraLoaderMixin` with LoRA loading/saving code that's specific to SDXL"""
1307

M. Tolga Cangöz's avatar
M. Tolga Cangöz committed
1308
    # Override to properly handle the loading and unloading of the additional text encoder.
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
    def load_lora_weights(
        self,
        pretrained_model_name_or_path_or_dict: Union[str, Dict[str, torch.Tensor]],
        adapter_name: Optional[str] = None,
        **kwargs,
    ):
        """
        Load LoRA weights specified in `pretrained_model_name_or_path_or_dict` into `self.unet` and
        `self.text_encoder`.

        All kwargs are forwarded to `self.lora_state_dict`.

        See [`~loaders.LoraLoaderMixin.lora_state_dict`] for more details on how the state dict is loaded.

        See [`~loaders.LoraLoaderMixin.load_lora_into_unet`] for more details on how the state dict is loaded into
        `self.unet`.

        See [`~loaders.LoraLoaderMixin.load_lora_into_text_encoder`] for more details on how the state dict is loaded
        into `self.text_encoder`.

        Parameters:
            pretrained_model_name_or_path_or_dict (`str` or `os.PathLike` or `dict`):
                See [`~loaders.LoraLoaderMixin.lora_state_dict`].
Steven Liu's avatar
Steven Liu committed
1332
            adapter_name (`str`, *optional*):
1333
1334
1335
1336
                Adapter name to be used for referencing the loaded adapter model. If not specified, it will use
                `default_{i}` where i is the total number of adapters being loaded.
            kwargs (`dict`, *optional*):
                See [`~loaders.LoraLoaderMixin.lora_state_dict`].
1337
        """
1338
1339
1340
        if not USE_PEFT_BACKEND:
            raise ValueError("PEFT backend is required for this method.")

1341
1342
1343
1344
        # We could have accessed the unet config from `lora_state_dict()` too. We pass
        # it here explicitly to be able to tell that it's coming from an SDXL
        # pipeline.

1345
1346
1347
1348
        # if a dict is passed, copy it instead of modifying it inplace
        if isinstance(pretrained_model_name_or_path_or_dict, dict):
            pretrained_model_name_or_path_or_dict = pretrained_model_name_or_path_or_dict.copy()

1349
1350
1351
1352
1353
1354
        # First, ensure that the checkpoint is a compatible one and can be successfully loaded.
        state_dict, network_alphas = self.lora_state_dict(
            pretrained_model_name_or_path_or_dict,
            unet_config=self.unet.config,
            **kwargs,
        )
1355
        is_correct_format = all("lora" in key or "dora_scale" in key for key in state_dict.keys())
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
        if not is_correct_format:
            raise ValueError("Invalid LoRA checkpoint.")

        self.load_lora_into_unet(
            state_dict, network_alphas=network_alphas, unet=self.unet, adapter_name=adapter_name, _pipeline=self
        )
        text_encoder_state_dict = {k: v for k, v in state_dict.items() if "text_encoder." in k}
        if len(text_encoder_state_dict) > 0:
            self.load_lora_into_text_encoder(
                text_encoder_state_dict,
                network_alphas=network_alphas,
                text_encoder=self.text_encoder,
                prefix="text_encoder",
                lora_scale=self.lora_scale,
                adapter_name=adapter_name,
                _pipeline=self,
            )

        text_encoder_2_state_dict = {k: v for k, v in state_dict.items() if "text_encoder_2." in k}
        if len(text_encoder_2_state_dict) > 0:
            self.load_lora_into_text_encoder(
                text_encoder_2_state_dict,
                network_alphas=network_alphas,
                text_encoder=self.text_encoder_2,
                prefix="text_encoder_2",
                lora_scale=self.lora_scale,
                adapter_name=adapter_name,
                _pipeline=self,
            )

    @classmethod
    def save_lora_weights(
        cls,
        save_directory: Union[str, os.PathLike],
        unet_lora_layers: Dict[str, Union[torch.nn.Module, torch.Tensor]] = None,
        text_encoder_lora_layers: Dict[str, Union[torch.nn.Module, torch.Tensor]] = None,
        text_encoder_2_lora_layers: Dict[str, Union[torch.nn.Module, torch.Tensor]] = None,
        is_main_process: bool = True,
        weight_name: str = None,
        save_function: Callable = None,
        safe_serialization: bool = True,
    ):
        r"""
        Save the LoRA parameters corresponding to the UNet and text encoder.

        Arguments:
            save_directory (`str` or `os.PathLike`):
                Directory to save LoRA parameters to. Will be created if it doesn't exist.
            unet_lora_layers (`Dict[str, torch.nn.Module]` or `Dict[str, torch.Tensor]`):
                State dict of the LoRA layers corresponding to the `unet`.
            text_encoder_lora_layers (`Dict[str, torch.nn.Module]` or `Dict[str, torch.Tensor]`):
                State dict of the LoRA layers corresponding to the `text_encoder`. Must explicitly pass the text
                encoder LoRA state dict because it comes from 🤗 Transformers.
1409
1410
1411
            text_encoder_2_lora_layers (`Dict[str, torch.nn.Module]` or `Dict[str, torch.Tensor]`):
                State dict of the LoRA layers corresponding to the `text_encoder_2`. Must explicitly pass the text
                encoder LoRA state dict because it comes from 🤗 Transformers.
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
            is_main_process (`bool`, *optional*, defaults to `True`):
                Whether the process calling this is the main process or not. Useful during distributed training and you
                need to call this function on all processes. In this case, set `is_main_process=True` only on the main
                process to avoid race conditions.
            save_function (`Callable`):
                The function to use to save the state dictionary. Useful during distributed training when you need to
                replace `torch.save` with another method. Can be configured with the environment variable
                `DIFFUSERS_SAVE_MODE`.
            safe_serialization (`bool`, *optional*, defaults to `True`):
                Whether to save the model using `safetensors` or the traditional PyTorch way with `pickle`.
        """
        state_dict = {}

        def pack_weights(layers, prefix):
            layers_weights = layers.state_dict() if isinstance(layers, torch.nn.Module) else layers
            layers_state_dict = {f"{prefix}.{module_name}": param for module_name, param in layers_weights.items()}
            return layers_state_dict

        if not (unet_lora_layers or text_encoder_lora_layers or text_encoder_2_lora_layers):
            raise ValueError(
                "You must pass at least one of `unet_lora_layers`, `text_encoder_lora_layers` or `text_encoder_2_lora_layers`."
            )

        if unet_lora_layers:
            state_dict.update(pack_weights(unet_lora_layers, "unet"))

1438
        if text_encoder_lora_layers:
1439
            state_dict.update(pack_weights(text_encoder_lora_layers, "text_encoder"))
1440
1441

        if text_encoder_2_lora_layers:
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
            state_dict.update(pack_weights(text_encoder_2_lora_layers, "text_encoder_2"))

        cls.write_lora_layers(
            state_dict=state_dict,
            save_directory=save_directory,
            is_main_process=is_main_process,
            weight_name=weight_name,
            save_function=save_function,
            safe_serialization=safe_serialization,
        )

    def _remove_text_encoder_monkey_patch(self):
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
        recurse_remove_peft_layers(self.text_encoder)
        # TODO: @younesbelkada handle this in transformers side
        if getattr(self.text_encoder, "peft_config", None) is not None:
            del self.text_encoder.peft_config
            self.text_encoder._hf_peft_config_loaded = None

        recurse_remove_peft_layers(self.text_encoder_2)
        if getattr(self.text_encoder_2, "peft_config", None) is not None:
            del self.text_encoder_2.peft_config
            self.text_encoder_2._hf_peft_config_loaded = None