Add llama2 / torch models for ollama create (#3607)

convert/llama.go

@@ -0,0 +1,176 @@
+package convert
+
+import (
+	"encoding/binary"
+	"fmt"
+	"io"
+	"log/slog"
+	"os"
+	"regexp"
+	"strings"
+
+	"github.com/nlpodyssey/gopickle/pytorch"
+	"github.com/pdevine/tensor"
+	"github.com/pdevine/tensor/native"
+	"github.com/x448/float16"
+
+	"github.com/ollama/ollama/llm"
+)
+
+type LlamaModel struct {
+	ModelData
+}
+
+func llamaLayerHandler(w io.Writer, r torchWriterTo) error {
+	slog.Debug(fmt.Sprintf("repacking layer '%s'", r.t.Name))
+
+	data := r.storage.(*pytorch.HalfStorage).Data
+	tData := make([]uint16, len(data))
+	for cnt, v := range data {
+		tData[cnt] = uint16(float16.Fromfloat32(v))
+	}
+
+	var err error
+	var heads uint32
+	if strings.Contains(r.t.Name, "attn_q") {
+		heads = uint32(r.params.AttentionHeads)
+	} else if strings.Contains(r.t.Name, "attn_k") {
+		heads = uint32(r.params.KeyValHeads)
+		if heads == 0 {
+			heads = uint32(r.params.AttentionHeads)
+		}
+	} else {
+		return fmt.Errorf("unknown layer type")
+	}
+
+	slog.Debug(fmt.Sprintf("heads = %d", heads))
+
+	tData, err = llamaRepack(tData, int(heads), r.t.Shape)
+	if err != nil {
+		return err
+	}
+
+	if err = binary.Write(w, r.bo, tData); err != nil {
+		return err
+	}
+	return nil
+}
+
+func llamaRepack(data []uint16, heads int, shape []uint64) ([]uint16, error) {
+	n := tensor.New(tensor.WithShape(int(shape[0]), int(shape[1])), tensor.WithBacking(data))
+	origShape := n.Shape().Clone()
+
+	// reshape the tensor and swap axes 1 and 2 to unpack the layer for gguf
+	if err := n.Reshape(heads, 2, origShape[0]/heads/2, origShape[1]); err != nil {
+		return nil, err
+	}
+
+	if err := n.T(0, 2, 1, 3); err != nil {
+		return nil, err
+	}
+
+	if err := n.Reshape(origShape...); err != nil {
+		return nil, err
+	}
+
+	if err := n.Transpose(); err != nil {
+		return nil, err
+	}
+	newN, err := native.SelectU16(n, 1)
+	if err != nil {
+		return nil, err
+	}
+
+	var fullTensor []uint16
+	for _, v := range newN {
+		fullTensor = append(fullTensor, v...)
+	}
+	return fullTensor, nil
+}
+
+func (m *LlamaModel) GetTensors() error {
+	t, err := m.Format.GetTensors(m.Path, m.Params)
+	if err != nil {
+		return err
+	}
+
+	m.Tensors = []llm.Tensor{}
+
+	pattern := `^blk\.[0-9]+\.attn_(?P<layer>q|k)\.weight$`
+	re, err := regexp.Compile(pattern)
+	if err != nil {
+		return err
+	}
+
+	for _, l := range t {
+		matches := re.FindAllStringSubmatch(l.Name, -1)
+		if len(matches) > 0 {
+			slog.Debug(fmt.Sprintf("setting handler for: %s", l.Name))
+			wt := l.WriterTo.(torchWriterTo)
+			wt.handler = llamaLayerHandler
+			l.WriterTo = wt
+		}
+		m.Tensors = append(m.Tensors, l)
+	}
+
+	return nil
+}
+
+func (m *LlamaModel) LoadVocab() error {
+	var v *Vocab
+	var err error
+
+	slog.Debug("loading vocab")
+	v, err = LoadSentencePieceTokens(m.Path, m.Params)
+	if err != nil {
+		return err
+	}
+
+	slog.Debug("vocab loaded")
+
+	m.Vocab = v
+	return nil
+}
+
+func (m *LlamaModel) WriteGGUF() (string, error) {
+	kv := llm.KV{
+		"general.architecture":                   "llama",
+		"general.name":                           m.Name,
+		"llama.vocab_size":                       uint32(len(m.Vocab.Tokens)),
+		"llama.context_length":                   uint32(m.Params.ContextSize),
+		"llama.embedding_length":                 uint32(m.Params.HiddenSize),
+		"llama.block_count":                      uint32(m.Params.HiddenLayers),
+		"llama.feed_forward_length":              uint32(m.Params.IntermediateSize),
+		"llama.rope.dimension_count":             uint32(m.Params.HiddenSize / m.Params.AttentionHeads),
+		"llama.attention.head_count":             uint32(m.Params.AttentionHeads),
+		"llama.attention.head_count_kv":          uint32(m.Params.KeyValHeads),
+		"llama.attention.layer_norm_rms_epsilon": float32(m.Params.NormEPS),
+		"general.file_type":                      uint32(1),
+		"tokenizer.ggml.model":                   "llama",
+
+		"tokenizer.ggml.tokens":     m.Vocab.Tokens,
+		"tokenizer.ggml.scores":     m.Vocab.Scores,
+		"tokenizer.ggml.token_type": m.Vocab.Types,
+
+		"tokenizer.ggml.bos_token_id":     uint32(m.Params.BoSTokenID),
+		"tokenizer.ggml.eos_token_id":     uint32(m.Params.EoSTokenID),
+		"tokenizer.ggml.unknown_token_id": uint32(0),
+		"tokenizer.ggml.add_bos_token":    true,
+		"tokenizer.ggml.add_eos_token":    false,
+	}
+
+	f, err := os.CreateTemp("", "ollama-gguf")
+	if err != nil {
+		return "", err
+	}
+	defer f.Close()
+
+	mod := llm.NewGGUFV3(m.Params.ByteOrder)
+	if err := mod.Encode(f, kv, m.Tensors); err != nil {
+		return "", err
+	}
+
+	slog.Debug(fmt.Sprintf("gguf file = %s", f.Name()))
+
+	return f.Name(), nil
+}