KohyaSS/networks/lora.py
2023-03-09 11:06:59 -05:00

388 lines
14 KiB
Python

# LoRA network module
# reference:
# https://github.com/microsoft/LoRA/blob/main/loralib/layers.py
# https://github.com/cloneofsimo/lora/blob/master/lora_diffusion/lora.py
import math
import os
from typing import List
import numpy as np
import torch
from library import train_util
class LoRAModule(torch.nn.Module):
"""
replaces forward method of the original Linear, instead of replacing the original Linear module.
"""
def __init__(self, lora_name, org_module: torch.nn.Module, multiplier=1.0, lora_dim=4, alpha=1):
""" if alpha == 0 or None, alpha is rank (no scaling). """
super().__init__()
self.lora_name = lora_name
self.lora_dim = lora_dim
if org_module.__class__.__name__ == 'Conv2d':
in_dim = org_module.in_channels
out_dim = org_module.out_channels
self.lora_dim = min(self.lora_dim, in_dim, out_dim)
if self.lora_dim != lora_dim:
print(f"{lora_name} dim (rank) is changed to: {self.lora_dim}")
kernel_size = org_module.kernel_size
stride = org_module.stride
padding = org_module.padding
self.lora_down = torch.nn.Conv2d(in_dim, self.lora_dim, kernel_size, stride, padding, bias=False)
self.lora_up = torch.nn.Conv2d(self.lora_dim, out_dim, (1, 1), (1, 1), bias=False)
else:
in_dim = org_module.in_features
out_dim = org_module.out_features
self.lora_down = torch.nn.Linear(in_dim, lora_dim, bias=False)
self.lora_up = torch.nn.Linear(lora_dim, out_dim, bias=False)
if type(alpha) == torch.Tensor:
alpha = alpha.detach().float().numpy() # without casting, bf16 causes error
alpha = lora_dim if alpha is None or alpha == 0 else alpha
self.scale = alpha / self.lora_dim
self.register_buffer('alpha', torch.tensor(alpha)) # 定数として扱える
# same as microsoft's
torch.nn.init.kaiming_uniform_(self.lora_down.weight, a=math.sqrt(5))
torch.nn.init.zeros_(self.lora_up.weight)
self.multiplier = multiplier
self.org_module = org_module # remove in applying
self.region = None
self.region_mask = None
def apply_to(self):
self.org_forward = self.org_module.forward
self.org_module.forward = self.forward
del self.org_module
def set_region(self, region):
self.region = region
self.region_mask = None
def forward(self, x):
if self.region is None:
return self.org_forward(x) + self.lora_up(self.lora_down(x)) * self.multiplier * self.scale
# regional LoRA FIXME same as additional-network extension
if x.size()[1] % 77 == 0:
# print(f"LoRA for context: {self.lora_name}")
self.region = None
return self.org_forward(x) + self.lora_up(self.lora_down(x)) * self.multiplier * self.scale
# calculate region mask first time
if self.region_mask is None:
if len(x.size()) == 4:
h, w = x.size()[2:4]
else:
seq_len = x.size()[1]
ratio = math.sqrt((self.region.size()[0] * self.region.size()[1]) / seq_len)
h = int(self.region.size()[0] / ratio + .5)
w = seq_len // h
r = self.region.to(x.device)
if r.dtype == torch.bfloat16:
r = r.to(torch.float)
r = r.unsqueeze(0).unsqueeze(1)
# print(self.lora_name, self.region.size(), x.size(), r.size(), h, w)
r = torch.nn.functional.interpolate(r, (h, w), mode='bilinear')
r = r.to(x.dtype)
if len(x.size()) == 3:
r = torch.reshape(r, (1, x.size()[1], -1))
self.region_mask = r
return self.org_forward(x) + self.lora_up(self.lora_down(x)) * self.multiplier * self.scale * self.region_mask
def create_network(multiplier, network_dim, network_alpha, vae, text_encoder, unet, **kwargs):
if network_dim is None:
network_dim = 4 # default
# extract dim/alpha for conv2d, and block dim
conv_dim = kwargs.get('conv_dim', None)
conv_alpha = kwargs.get('conv_alpha', None)
if conv_dim is not None:
conv_dim = int(conv_dim)
if conv_alpha is None:
conv_alpha = 1.0
else:
conv_alpha = float(conv_alpha)
"""
block_dims = kwargs.get("block_dims")
block_alphas = None
if block_dims is not None:
block_dims = [int(d) for d in block_dims.split(',')]
assert len(block_dims) == NUM_BLOCKS, f"Number of block dimensions is not same to {NUM_BLOCKS}"
block_alphas = kwargs.get("block_alphas")
if block_alphas is None:
block_alphas = [1] * len(block_dims)
else:
block_alphas = [int(a) for a in block_alphas(',')]
assert len(block_alphas) == NUM_BLOCKS, f"Number of block alphas is not same to {NUM_BLOCKS}"
conv_block_dims = kwargs.get("conv_block_dims")
conv_block_alphas = None
if conv_block_dims is not None:
conv_block_dims = [int(d) for d in conv_block_dims.split(',')]
assert len(conv_block_dims) == NUM_BLOCKS, f"Number of block dimensions is not same to {NUM_BLOCKS}"
conv_block_alphas = kwargs.get("conv_block_alphas")
if conv_block_alphas is None:
conv_block_alphas = [1] * len(conv_block_dims)
else:
conv_block_alphas = [int(a) for a in conv_block_alphas(',')]
assert len(conv_block_alphas) == NUM_BLOCKS, f"Number of block alphas is not same to {NUM_BLOCKS}"
"""
network = LoRANetwork(text_encoder, unet, multiplier=multiplier, lora_dim=network_dim,
alpha=network_alpha, conv_lora_dim=conv_dim, conv_alpha=conv_alpha)
return network
def create_network_from_weights(multiplier, file, vae, text_encoder, unet, **kwargs):
if os.path.splitext(file)[1] == '.safetensors':
from safetensors.torch import load_file, safe_open
weights_sd = load_file(file)
else:
weights_sd = torch.load(file, map_location='cpu')
# get dim/alpha mapping
modules_dim = {}
modules_alpha = {}
for key, value in weights_sd.items():
if '.' not in key:
continue
lora_name = key.split('.')[0]
if 'alpha' in key:
modules_alpha[lora_name] = value
elif 'lora_down' in key:
dim = value.size()[0]
modules_dim[lora_name] = dim
# print(lora_name, value.size(), dim)
# support old LoRA without alpha
for key in modules_dim.keys():
if key not in modules_alpha:
modules_alpha = modules_dim[key]
network = LoRANetwork(text_encoder, unet, multiplier=multiplier, modules_dim=modules_dim, modules_alpha=modules_alpha)
network.weights_sd = weights_sd
return network
class LoRANetwork(torch.nn.Module):
# is it possible to apply conv_in and conv_out?
UNET_TARGET_REPLACE_MODULE = ["Transformer2DModel", "Attention", "ResnetBlock2D", "Downsample2D", "Upsample2D"]
TEXT_ENCODER_TARGET_REPLACE_MODULE = ["CLIPAttention", "CLIPMLP"]
LORA_PREFIX_UNET = 'lora_unet'
LORA_PREFIX_TEXT_ENCODER = 'lora_te'
def __init__(self, text_encoder, unet, multiplier=1.0, lora_dim=4, alpha=1, conv_lora_dim=None, conv_alpha=None, modules_dim=None, modules_alpha=None) -> None:
super().__init__()
self.multiplier = multiplier
self.lora_dim = lora_dim
self.alpha = alpha
self.conv_lora_dim = conv_lora_dim
self.conv_alpha = conv_alpha
if modules_dim is not None:
print(f"create LoRA network from weights")
else:
print(f"create LoRA network. base dim (rank): {lora_dim}, alpha: {alpha}")
self.apply_to_conv2d_3x3 = self.conv_lora_dim is not None
if self.apply_to_conv2d_3x3:
if self.conv_alpha is None:
self.conv_alpha = self.alpha
print(f"apply LoRA to Conv2d with kernel size (3,3). dim (rank): {self.conv_lora_dim}, alpha: {self.conv_alpha}")
# create module instances
def create_modules(prefix, root_module: torch.nn.Module, target_replace_modules) -> List[LoRAModule]:
loras = []
for name, module in root_module.named_modules():
if module.__class__.__name__ in target_replace_modules:
# TODO get block index here
for child_name, child_module in module.named_modules():
is_linear = child_module.__class__.__name__ == "Linear"
is_conv2d = child_module.__class__.__name__ == "Conv2d"
is_conv2d_1x1 = is_conv2d and child_module.kernel_size == (1, 1)
if is_linear or is_conv2d:
lora_name = prefix + '.' + name + '.' + child_name
lora_name = lora_name.replace('.', '_')
if modules_dim is not None:
if lora_name not in modules_dim:
continue # no LoRA module in this weights file
dim = modules_dim[lora_name]
alpha = modules_alpha[lora_name]
else:
if is_linear or is_conv2d_1x1:
dim = self.lora_dim
alpha = self.alpha
elif self.apply_to_conv2d_3x3:
dim = self.conv_lora_dim
alpha = self.conv_alpha
else:
continue
lora = LoRAModule(lora_name, child_module, self.multiplier, dim, alpha)
loras.append(lora)
return loras
self.text_encoder_loras = create_modules(LoRANetwork.LORA_PREFIX_TEXT_ENCODER,
text_encoder, LoRANetwork.TEXT_ENCODER_TARGET_REPLACE_MODULE)
print(f"create LoRA for Text Encoder: {len(self.text_encoder_loras)} modules.")
self.unet_loras = create_modules(LoRANetwork.LORA_PREFIX_UNET, unet, LoRANetwork.UNET_TARGET_REPLACE_MODULE)
print(f"create LoRA for U-Net: {len(self.unet_loras)} modules.")
self.weights_sd = None
# assertion
names = set()
for lora in self.text_encoder_loras + self.unet_loras:
assert lora.lora_name not in names, f"duplicated lora name: {lora.lora_name}"
names.add(lora.lora_name)
def set_multiplier(self, multiplier):
self.multiplier = multiplier
for lora in self.text_encoder_loras + self.unet_loras:
lora.multiplier = self.multiplier
def load_weights(self, file):
if os.path.splitext(file)[1] == '.safetensors':
from safetensors.torch import load_file, safe_open
self.weights_sd = load_file(file)
else:
self.weights_sd = torch.load(file, map_location='cpu')
def apply_to(self, text_encoder, unet, apply_text_encoder=None, apply_unet=None):
if self.weights_sd:
weights_has_text_encoder = weights_has_unet = False
for key in self.weights_sd.keys():
if key.startswith(LoRANetwork.LORA_PREFIX_TEXT_ENCODER):
weights_has_text_encoder = True
elif key.startswith(LoRANetwork.LORA_PREFIX_UNET):
weights_has_unet = True
if apply_text_encoder is None:
apply_text_encoder = weights_has_text_encoder
else:
assert apply_text_encoder == weights_has_text_encoder, f"text encoder weights: {weights_has_text_encoder} but text encoder flag: {apply_text_encoder} / 重みとText Encoderのフラグが矛盾しています"
if apply_unet is None:
apply_unet = weights_has_unet
else:
assert apply_unet == weights_has_unet, f"u-net weights: {weights_has_unet} but u-net flag: {apply_unet} / 重みとU-Netのフラグが矛盾しています"
else:
assert apply_text_encoder is not None and apply_unet is not None, f"internal error: flag not set"
if apply_text_encoder:
print("enable LoRA for text encoder")
else:
self.text_encoder_loras = []
if apply_unet:
print("enable LoRA for U-Net")
else:
self.unet_loras = []
for lora in self.text_encoder_loras + self.unet_loras:
lora.apply_to()
self.add_module(lora.lora_name, lora)
if self.weights_sd:
# if some weights are not in state dict, it is ok because initial LoRA does nothing (lora_up is initialized by zeros)
info = self.load_state_dict(self.weights_sd, False)
print(f"weights are loaded: {info}")
def enable_gradient_checkpointing(self):
# not supported
pass
def prepare_optimizer_params(self, text_encoder_lr, unet_lr):
def enumerate_params(loras):
params = []
for lora in loras:
params.extend(lora.parameters())
return params
self.requires_grad_(True)
all_params = []
if self.text_encoder_loras:
param_data = {'params': enumerate_params(self.text_encoder_loras)}
if text_encoder_lr is not None:
param_data['lr'] = text_encoder_lr
all_params.append(param_data)
if self.unet_loras:
param_data = {'params': enumerate_params(self.unet_loras)}
if unet_lr is not None:
param_data['lr'] = unet_lr
all_params.append(param_data)
return all_params
def prepare_grad_etc(self, text_encoder, unet):
self.requires_grad_(True)
def on_epoch_start(self, text_encoder, unet):
self.train()
def get_trainable_params(self):
return self.parameters()
def save_weights(self, file, dtype, metadata):
if metadata is not None and len(metadata) == 0:
metadata = None
state_dict = self.state_dict()
if dtype is not None:
for key in list(state_dict.keys()):
v = state_dict[key]
v = v.detach().clone().to("cpu").to(dtype)
state_dict[key] = v
if os.path.splitext(file)[1] == '.safetensors':
from safetensors.torch import save_file
# Precalculate model hashes to save time on indexing
if metadata is None:
metadata = {}
model_hash, legacy_hash = train_util.precalculate_safetensors_hashes(state_dict, metadata)
metadata["sshs_model_hash"] = model_hash
metadata["sshs_legacy_hash"] = legacy_hash
save_file(state_dict, file, metadata)
else:
torch.save(state_dict, file)
@staticmethod
def set_regions(networks, image):
image = image.astype(np.float32) / 255.0
for i, network in enumerate(networks[:3]):
# NOTE: consider averaging overwrapping area
region = image[:, :, i]
if region.max() == 0:
continue
region = torch.tensor(region)
network.set_region(region)
def set_region(self, region):
for lora in self.unet_loras:
lora.set_region(region)