[CustomOp][MM] Extract MMEncoderAttention as CustomOp and replace the backend of QwenVisionAttention with it. (#30125)

Signed-off-by: shen-shanshan <467638484@qq.com>
Signed-off-by: Isotr0py <mozf@mail2.sysu.edu.cn>
Signed-off-by: tjtanaa <tunjian.tan@embeddedllm.com>
Co-authored-by: Isotr0py <mozf@mail2.sysu.edu.cn>
Co-authored-by: tjtanaa <tunjian.tan@embeddedllm.com>

tests/models/multimodal/generation/test_vit_backend_functionality.py

@@ -0,0 +1,434 @@
+# SPDX-License-Identifier: Apache-2.0
+# SPDX-FileCopyrightText: Copyright contributors to the vLLM project
+"""
+Consolidated test for ViT attention backend functionality across multiple models.
+
+This test validates that each multimodal model can successfully generate outputs
+using different ViT attention backends. Tests are parametrized by model and backend.
+"""
+
+from dataclasses import asdict
+from typing import Any
+
+import pytest
+from transformers import AutoProcessor
+
+from vllm import LLM, EngineArgs, SamplingParams
+from vllm.attention.backends.registry import AttentionBackendEnum
+from vllm.multimodal.utils import encode_image_base64
+from vllm.multimodal.video import sample_frames_from_video
+from vllm.platforms import current_platform
+
+from ....utils import create_new_process_for_each_test
+from ...utils import dummy_hf_overrides
+
+# Dots.OCR prompt from official repository
+# https://github.com/rednote-hilab/dots.ocr/blob/d72d1d8c5bdd0362eb264f714cdbd1e5daa7cdff/dots_ocr/utils/prompts.py#L3
+# ruff: noqa: E501
+DOTS_OCR_PROMPT = """Please output the layout information from the PDF image, including each layout element's bbox, its category, and the corresponding text content within the bbox.
+
+1. Bbox format: [x1, y1, x2, y2]
+
+2. Layout Categories: The possible categories are ['Caption', 'Footnote', 'Formula', 'List-item', 'Page-footer', 'Page-header', 'Picture', 'Section-header', 'Table', 'Text', 'Title'].
+
+3. Text Extraction & Formatting Rules:
+    - Picture: For the 'Picture' category, the text field should be omitted.
+    - Formula: Format its text as LaTeX.
+    - Table: Format its text as HTML.
+    - All Others (Text, Title, etc.): Format their text as Markdown.
+
+4. Constraints:
+    - The output text must be the original text from the image, with no translation.
+    - All layout elements must be sorted according to human reading order.
+
+5. Final Output: The entire output must be a single JSON object.
+"""
+
+VIDEO_PLACEHOLDER = "<|vision_start|><|video_pad|><|vision_end|>"
+
+
+# Model configurations
+MODEL_CONFIGS: dict[str, dict[str, Any]] = {
+    "dots_ocr": {
+        "model_name": "rednote-hilab/dots.ocr",
+        "interface": "llm_chat",
+        "max_model_len": 32768,
+        "max_num_seqs": 1,
+        "limit_mm_per_prompt": {"image": 1},
+        "sampling_params": {
+            "temperature": 0.1,
+            "max_tokens": 16384,
+            "top_p": 0.9,
+            "stop_token_ids": None,
+        },
+        "use_specific_image": "stop_sign",
+        "prompt_builder": "build_dots_ocr_prompt",
+        "output_validator": lambda x: len(x) > 10 and "stop" in x.lower(),
+    },
+    "ernie45_vl": {
+        "model_name": "baidu/ERNIE-4.5-VL-28B-A3B-PT",
+        "interface": "llm_generate",
+        "max_model_len": 16384,
+        "max_num_seqs": 2,
+        "sampling_params": {
+            "temperature": 0.0,
+            "max_tokens": 256,
+            "stop_token_ids": None,
+        },
+        "use_processor": True,
+        "question": "What is the content of each image?",
+    },
+    "glm4_1v": {
+        "model_name": "zai-org/GLM-4.1V-9B-Thinking",
+        "interface": "llm_generate",
+        "max_model_len": 32768,
+        "max_num_seqs": 2,
+        "sampling_params": {
+            "temperature": 0.0,
+            "max_tokens": 256,
+            "stop_token_ids": None,
+        },
+        "use_processor": True,
+        "question": "What is the content of each image?",
+    },
+    "keye_vl": {
+        "model_name": "Kwai-Keye/Keye-VL-8B-Preview",
+        "interface": "llm_generate",
+        "max_model_len": 8192,
+        "max_num_seqs": 5,
+        "sampling_params": {
+            "temperature": 0.0,
+            "max_tokens": 256,
+            "stop_token_ids": None,
+        },
+        "supported_backends": {
+            AttentionBackendEnum.FLASH_ATTN,
+            AttentionBackendEnum.ROCM_AITER_FA,
+        },
+        "use_processor": True,
+        "question": "What is the content of each image?",
+    },
+    "ovis2_5": {
+        "model_name": "AIDC-AI/Ovis2.5-2B",
+        "interface": "llm_generate",
+        "max_model_len": 8192,
+        "max_num_seqs": 2,
+        "sampling_params": {
+            "temperature": 0.0,
+            "max_tokens": 256,
+            "stop_token_ids": None,
+        },
+        "prompt_builder": "build_ovis_prompt",
+        "question": "What is the content of each image?",
+    },
+    "qwen2_5_vl": {
+        "model_name": "Qwen/Qwen2.5-VL-3B-Instruct",
+        "interface": "vllm_runner",
+        "media_type": "video",
+        "max_model_len": 4000,
+        "max_num_seqs": 1,
+        "limit_mm_per_prompt": {"video": 1},
+        "sampling_params": {
+            "max_tokens": 128,
+        },
+        "runner_kwargs": {
+            "runner": "generate",
+            "dtype": "bfloat16",
+        },
+        "video_params": {
+            "num_frames": 16,
+            "pruning_rates": [0.0, 0.75],
+        },
+    },
+    "qwen2_5_omni": {
+        "model_name": "Qwen/Qwen2.5-Omni-3B",
+        "interface": "llm_generate",
+        "max_model_len": 32768,
+        "max_num_seqs": 2,
+        "limit_mm_per_prompt": {"image": 3, "video": 3, "audio": 3},
+        "sampling_params": {
+            "temperature": 0.6,
+            "top_p": 0.95,
+            "top_k": 20,
+            "max_tokens": 16384,
+        },
+        "use_processor": True,
+        "question": "What is the content of each image?",
+    },
+    "qwen3_omni": {
+        "model_name": "Qwen/Qwen3-Omni-30B-A3B-Instruct",
+        "interface": "llm_generate",
+        "max_model_len": 32768,
+        "max_num_seqs": 2,
+        "limit_mm_per_prompt": {"image": 3, "video": 3, "audio": 3},
+        "sampling_params": {
+            "temperature": 0.6,
+            "top_p": 0.95,
+            "top_k": 20,
+            "max_tokens": 16384,
+        },
+        "use_processor": True,
+        "question": "What is the content of each image?",
+    },
+}
+
+
+# Prompt builder functions
+def build_dots_ocr_prompt(images, config):
+    """Build Dots.OCR specific prompt with OCR instructions."""
+    # Use only stop_sign image for Dots.OCR
+    image = images[0]  # Already filtered to stop_sign
+
+    image_url = f"data:image/jpeg;base64,{encode_image_base64(image)}"
+
+    placeholders = [{"type": "image_url", "image_url": {"url": image_url}}]
+    messages = [
+        {
+            "role": "user",
+            "content": [
+                *placeholders,
+                {
+                    "type": "text",
+                    "text": f"<|img|><|imgpad|><|endofimg|>{DOTS_OCR_PROMPT}",
+                },
+            ],
+        },
+    ]
+
+    return messages
+
+
+def build_processor_prompt(images, config):
+    """Build prompt using AutoProcessor.apply_chat_template()."""
+    processor = AutoProcessor.from_pretrained(
+        config["model_name"], trust_remote_code=True
+    )
+
+    image_urls = [
+        f"data:image/jpeg;base64,{encode_image_base64(img)}" for img in images
+    ]
+    placeholders = [{"type": "image", "image": url} for url in image_urls]
+    messages = [
+        {
+            "role": "user",
+            "content": [
+                *placeholders,
+                {"type": "text", "text": config["question"]},
+            ],
+        },
+    ]
+
+    return processor.apply_chat_template(
+        messages, tokenize=False, add_generation_prompt=True
+    )
+
+
+def build_ovis_prompt(images, config):
+    """Build Ovis2.5 specific prompt with custom format."""
+    image_urls = [
+        f"data:image/jpeg;base64,{encode_image_base64(img)}" for img in images
+    ]
+
+    placeholders = "\n".join(
+        f"Image-{i}: <image>\n" for i, _ in enumerate(image_urls, start=1)
+    )
+
+    return (
+        f"<|im_start|>user\n\n{placeholders}\n{config['question']}<|im_end|>\n"
+        "<|im_start|>assistant\n"
+    )
+
+
+def build_qwen2_5_video_prompt():
+    """Build Qwen2.5-VL video prompt with EVS placeholder."""
+    return (
+        f"<|im_start|>system\nYou are a helpful assistant.<|im_end|>\n"
+        f"<|im_start|>user\n{VIDEO_PLACEHOLDER}"
+        "Describe this video with a short sentence (no more than 20 words)"
+        "<|im_end|><|im_start|>assistant\n"
+    )
+
+
+# Handler functions
+def run_llm_generate_test(config, mm_encoder_attn_backend, image_assets):
+    """Standard LLM.generate() interface handler."""
+    images = [asset.pil_image for asset in image_assets]
+
+    # Build prompt
+    if config.get("use_processor"):
+        prompt = build_processor_prompt(images, config)
+    else:
+        prompt_builder_name = config.get("prompt_builder", "build_ovis_prompt")
+        prompt_builder = globals()[prompt_builder_name]
+        prompt = prompt_builder(images, config)
+
+    # Determine limit_mm_per_prompt
+    limit_mm_per_prompt = config.get("limit_mm_per_prompt", {"image": len(images)})
+
+    # Create engine
+    engine_args = EngineArgs(
+        model=config["model_name"],
+        trust_remote_code=True,
+        max_model_len=config["max_model_len"],
+        max_num_seqs=config["max_num_seqs"],
+        limit_mm_per_prompt=limit_mm_per_prompt,
+        mm_encoder_attn_backend=mm_encoder_attn_backend,
+        hf_overrides=dummy_hf_overrides,
+        load_format="dummy",
+    )
+
+    engine_dict = asdict(engine_args) | {"seed": 42}
+    llm = LLM(**engine_dict)
+
+    # Generate
+    sampling_params = SamplingParams(**config["sampling_params"])
+    outputs = llm.generate(
+        {
+            "prompt": prompt,
+            "multi_modal_data": {"image": images},
+        },
+        sampling_params=sampling_params,
+    )
+
+    # Validate
+    for o in outputs:
+        generated_text = o.outputs[0].text
+        validator = config.get("output_validator", lambda x: len(x) > 10)
+        assert validator(generated_text), (
+            f"Validation failed for {config['model_name']}: {generated_text}"
+        )
+
+
+def run_llm_chat_test(config, mm_encoder_attn_backend, image_assets):
+    """LLM.chat() interface handler for Dots.OCR."""
+    # Filter to stop_sign image only
+    stop_sign_image = [
+        asset.pil_image for asset in image_assets if asset.name == "stop_sign"
+    ][0]
+
+    # Build messages
+    messages = build_dots_ocr_prompt([stop_sign_image], config)
+
+    # Create engine
+    engine_args = EngineArgs(
+        model=config["model_name"],
+        trust_remote_code=True,
+        max_model_len=config["max_model_len"],
+        max_num_seqs=config["max_num_seqs"],
+        limit_mm_per_prompt=config["limit_mm_per_prompt"],
+        mm_encoder_attn_backend=mm_encoder_attn_backend,
+        hf_overrides=dummy_hf_overrides,
+        load_format="dummy",
+    )
+
+    engine_dict = asdict(engine_args) | {"seed": 42}
+    llm = LLM(**engine_dict)
+
+    # Generate using chat
+    sampling_params = SamplingParams(**config["sampling_params"])
+    outputs = llm.chat(messages=messages, sampling_params=sampling_params)
+
+    # Validate
+    for o in outputs:
+        generated_text = o.outputs[0].text
+        validator = config.get("output_validator", lambda x: len(x) > 10)
+        assert validator(generated_text), (
+            f"Validation failed for {config['model_name']}: {generated_text}"
+        )
+
+
+def run_video_test(config, mm_encoder_attn_backend, video_assets, vllm_runner):
+    """Video test with EVS (Efficient Video Sampling) handler."""
+    for pruning_rate in config["video_params"]["pruning_rates"]:
+        num_frames = config["video_params"]["num_frames"]
+
+        # Sample frames from video
+        sampled_vids = [
+            sample_frames_from_video(asset.np_ndarrays, num_frames)
+            for asset in video_assets
+        ]
+
+        # Build prompt and prepare video
+        prompt = build_qwen2_5_video_prompt()
+        prompts = [prompt]
+        videos = [sampled_vids[0]]
+
+        # Run with vllm_runner context manager
+        with vllm_runner(
+            config["model_name"],
+            max_model_len=config["max_model_len"],
+            max_num_seqs=config["max_num_seqs"],
+            limit_mm_per_prompt=config["limit_mm_per_prompt"],
+            tensor_parallel_size=1,
+            video_pruning_rate=pruning_rate,
+            mm_encoder_attn_backend=mm_encoder_attn_backend,
+            hf_overrides=dummy_hf_overrides,
+            load_format="dummy",
+            **config["runner_kwargs"],
+        ) as vllm_model:
+            outputs = vllm_model.generate_greedy(
+                prompts,
+                config["sampling_params"]["max_tokens"],
+                videos=videos,
+            )
+
+            # Validate output
+            assert len(outputs) == 1, f"Expected 1 output, got {len(outputs)}"
+            output_ids, output_text = outputs[0]
+            assert len(output_ids) > 0, "Generated no output IDs"
+            assert len(output_text) > 0, "Generated empty text"
+            assert isinstance(output_text, str), (
+                f"Output is not string: {type(output_text)}"
+            )
+
+
+# Main test function
+@pytest.mark.parametrize("model_key", list(MODEL_CONFIGS.keys()))
+@pytest.mark.parametrize(
+    "mm_encoder_attn_backend",
+    [None] + current_platform.get_supported_vit_attn_backends(),
+)
+@create_new_process_for_each_test()
+def test_vit_backend_functionality(
+    model_key: str,
+    mm_encoder_attn_backend: AttentionBackendEnum | None,
+    image_assets,
+    video_assets,
+    vllm_runner,
+    request,
+):
+    """Test ViT attention backend functionality for multimodal models.
+
+    This test validates that each model can successfully generate outputs
+    using different ViT attention backends. The test:
+    1. Filters unsupported backends per model
+    2. Applies appropriate GPU marks
+    3. Routes to the correct test handler based on interface
+    4. Validates output meets minimum requirements
+    """
+    config = MODEL_CONFIGS[model_key]
+
+    # Step 1: Backend filtering
+    if (
+        "supported_backends" in config
+        and mm_encoder_attn_backend is not None
+        and mm_encoder_attn_backend not in config["supported_backends"]
+    ):
+        pytest.skip(
+            f"{model_key} does not support {mm_encoder_attn_backend} backend now."
+        )
+
+    # Step 2: Apply GPU marks dynamically
+    if "gpu_marks" in config:
+        for mark in config["gpu_marks"]:
+            request.applymarker(mark)
+
+    # Step 3: Route to appropriate handler
+    if config.get("media_type") == "video":
+        run_video_test(config, mm_encoder_attn_backend, video_assets, vllm_runner)
+    elif config["interface"] == "llm_chat":
+        run_llm_chat_test(config, mm_encoder_attn_backend, image_assets)
+    elif config["interface"] == "llm_generate":
+        run_llm_generate_test(config, mm_encoder_attn_backend, image_assets)
+    else:
+        raise ValueError(f"Unknown interface: {config['interface']}")

vllm/attention/layer.py

@@ -3,7 +3,6 @@
 """Attention layer."""
 
 import functools
-from collections.abc import Callable
 from typing import cast
 
 import torch
@@ -17,6 +16,7 @@ from vllm.attention.backends.abstract import (
     MLAAttentionImpl,
 )
 from vllm.attention.backends.registry import AttentionBackendEnum
+from vllm.attention.layers.mm_encoder_attention import maybe_get_vit_flash_attn_backend
 from vllm.attention.selector import get_attn_backend
 from vllm.attention.utils.fa_utils import get_flash_attn_version
 from vllm.attention.utils.kv_sharing_utils import validate_kv_sharing_target
@@ -49,58 +49,9 @@ from vllm.v1.kv_cache_interface import (
     SlidingWindowSpec,
 )
 
-if current_platform.is_rocm():
-    from vllm.platforms.rocm import on_gfx9
-else:
-    on_gfx9 = lambda *args, **kwargs: False
-
-
-FP8_DTYPE = current_platform.fp8_dtype()
 logger = init_logger(__name__)
 
 
-def maybe_get_vit_flash_attn_backend(
-    attn_backend: AttentionBackendEnum,
-    attn_backend_override: AttentionBackendEnum | None = None,
-) -> tuple[AttentionBackendEnum, Callable | None]:
-    if current_platform.is_rocm():
-        if envs.VLLM_ROCM_USE_AITER and envs.VLLM_ROCM_USE_AITER_MHA and on_gfx9():
-            attn_backend = AttentionBackendEnum.ROCM_AITER_FA
-        elif (
-            attn_backend_override is None
-            and on_gfx9()
-            and attn_backend == AttentionBackendEnum.FLASH_ATTN
-        ):
-            pass
-        else:
-            return AttentionBackendEnum.TORCH_SDPA, None
-    elif current_platform.is_cuda():
-        pass
-    elif current_platform.is_xpu():
-        assert attn_backend == AttentionBackendEnum.FLASH_ATTN, (
-            "XPU platform only supports FLASH_ATTN as vision attention backend."
-        )
-        pass
-    else:
-        return AttentionBackendEnum.TORCH_SDPA, None
-
-    if attn_backend in {
-        AttentionBackendEnum.FLASH_ATTN,
-        AttentionBackendEnum.ROCM_AITER_FA,
-    }:
-        if attn_backend == AttentionBackendEnum.ROCM_AITER_FA:
-            from aiter import flash_attn_varlen_func
-        else:
-            try:
-                from vllm.attention.utils.fa_utils import flash_attn_varlen_func
-            except ImportError:
-                flash_attn_varlen_func = None
-    else:
-        flash_attn_varlen_func = None
-
-    return attn_backend, flash_attn_varlen_func
-
-
 def _init_kv_cache_quant(
     layer: nn.Module,
     quant_config: QuantizationConfig | None,
@@ -496,29 +447,15 @@ class MultiHeadAttention(nn.Module):
         attn_backend_override = None
         if multimodal_config is not None:
             attn_backend_override = multimodal_config.mm_encoder_attn_backend
-        backend = get_vit_attn_backend(
+
+        self.attn_backend = get_vit_attn_backend(
             head_size=head_size,
             dtype=dtype,
             attn_backend_override=attn_backend_override,
         )
 
-        self.attn_backend = (
+        self._flash_attn_varlen_func = maybe_get_vit_flash_attn_backend(
-            backend
+            self.attn_backend,
-            if backend
-            in {
-                AttentionBackendEnum.TORCH_SDPA,
-                AttentionBackendEnum.PALLAS,
-                AttentionBackendEnum.ROCM_AITER_FA,
-                AttentionBackendEnum.FLASH_ATTN,
-            }
-            else AttentionBackendEnum.TORCH_SDPA
-        )
-
-        self.attn_backend, self._flash_attn_varlen_func = (
-            maybe_get_vit_flash_attn_backend(
-                self.attn_backend,
-                attn_backend_override=attn_backend_override,
-            )
         )
 
         self.is_flash_attn_backend = self.attn_backend in {

vllm/attention/layers/mm_encoder_attention.py

@@ -0,0 +1,284 @@
+# SPDX-License-Identifier: Apache-2.0
+# SPDX-FileCopyrightText: Copyright contributors to the vLLM project
+
+from collections.abc import Callable
+
+import torch
+
+from vllm.attention.backends.registry import AttentionBackendEnum
+from vllm.attention.ops.vit_attn_wrappers import (
+    vit_flash_attn_wrapper,
+    vit_torch_sdpa_wrapper,
+)
+from vllm.config import MultiModalConfig
+from vllm.logger import init_logger
+from vllm.model_executor.custom_op import CustomOp
+from vllm.model_executor.models.vision import get_vit_attn_backend
+
+logger = init_logger(__name__)
+
+
+def maybe_get_vit_flash_attn_backend(
+    attn_backend: AttentionBackendEnum | None,
+) -> Callable | None:
+    # At this point,
+    # we already have the attn_backend,
+    # overriding logic is done in the platform-specific implementation.
+    # so we don't need to override backend here.
+    # Just return the attn_backend and flash_attn_varlen_func.
+
+    if attn_backend == AttentionBackendEnum.FLASH_ATTN:
+        from vllm.attention.utils.fa_utils import flash_attn_varlen_func
+    elif attn_backend == AttentionBackendEnum.ROCM_AITER_FA:
+        from aiter import flash_attn_varlen_func
+    else:
+        flash_attn_varlen_func = None
+
+    # if attn_backend is TORCH_SDPA,
+    # it will reach here and the flash_attn_varlen_func will be None.
+    return flash_attn_varlen_func
+
+
+@CustomOp.register("mm_encoder_attn")
+class MMEncoderAttention(CustomOp):
+    """Multi-headed attention without any cache, used for multimodal encoder."""
+
+    def __init__(
+        self,
+        num_heads: int,
+        head_size: int,
+        scale: float | None = None,
+        num_kv_heads: int | None = None,
+        prefix: str = "",
+        multimodal_config: MultiModalConfig | None = None,
+    ) -> None:
+        """
+        Args:
+            num_heads: number of attention heads per partition.
+            head_size: hidden_size per attention head.
+            scale: scale factor.
+            num_kv_heads: number of kv heads.
+            prefix: This has no effect, it is only here to make it easier to
+                    swap between Attention and MultiHeadAttention
+            multimodal_config: configs for multi-modal.
+        """
+        super().__init__()
+
+        self.num_heads = num_heads
+        self.head_size = head_size
+        self.scale = scale
+        self.num_kv_heads = num_heads if num_kv_heads is None else num_kv_heads
+        self.layer_name = prefix
+
+        assert self.num_heads % self.num_kv_heads == 0, (
+            f"num_heads ({self.num_heads}) is not "
+            f"divisible by num_kv_heads ({self.num_kv_heads})"
+        )
+        self.num_queries_per_kv = self.num_heads // self.num_kv_heads
+
+        # During model initialization, the default dtype is set as the model
+        # weight and activation dtype.
+        dtype = torch.get_default_dtype()
+
+        # Try to get vision attention backend from multimodal_config.
+        attn_backend_override = None
+        if multimodal_config is not None:
+            attn_backend_override = multimodal_config.mm_encoder_attn_backend
+
+        # Get device-specific vision attention backend.
+        self.attn_backend = get_vit_attn_backend(
+            head_size=head_size,
+            dtype=dtype,
+            attn_backend_override=attn_backend_override,
+        )
+
+        self.is_flash_attn_backend = self.attn_backend in {
+            AttentionBackendEnum.FLASH_ATTN,
+            AttentionBackendEnum.ROCM_AITER_FA,
+        }
+
+        self.flash_attn_varlen_func = maybe_get_vit_flash_attn_backend(
+            self.attn_backend,
+        )
+
+        logger.info_once(f"Using {self.attn_backend} for MMEncoderAttention.")
+
+    @classmethod
+    def enabled(cls) -> bool:
+        return True
+
+    def reshape_qkv_to_4d(
+        self,
+        query: torch.Tensor,
+        key: torch.Tensor,
+        value: torch.Tensor,
+        bsz: int,
+        q_len: int,
+        kv_len: int,
+    ) -> tuple[torch.Tensor, torch.Tensor, torch.Tensor]:
+        """
+        Reshape query, key, value to 4D tensors:
+        (batch_size, seq_len, num_heads, head_size)
+        """
+        query = query.view(bsz, q_len, self.num_heads, self.head_size)
+        key = key.view(bsz, kv_len, self.num_kv_heads, self.head_size)
+        value = value.view(bsz, kv_len, self.num_kv_heads, self.head_size)
+
+        if (num_repeat := self.num_queries_per_kv) > 1:
+            # Handle MQA and GQA
+            key = torch.repeat_interleave(key, num_repeat, dim=2)
+            value = torch.repeat_interleave(value, num_repeat, dim=2)
+
+        return query, key, value
+
+    def reshape_qkv_to_3d(
+        self,
+        query: torch.Tensor,
+        key: torch.Tensor,
+        value: torch.Tensor,
+        bsz: int,
+        q_len: int,
+        kv_len: int,
+    ) -> tuple[torch.Tensor, torch.Tensor, torch.Tensor]:
+        """
+        Reshape query, key, value to 3D tensors:
+        (batch_size * seq_len, num_heads, head_size)
+        """
+        query = query.view(bsz * q_len, self.num_heads, self.head_size)
+        key = key.view(bsz * kv_len, self.num_kv_heads, self.head_size)
+        value = value.view(bsz * kv_len, self.num_kv_heads, self.head_size)
+
+        if (num_repeat := self.num_queries_per_kv) > 1:
+            # Handle MQA and GQA
+            key = torch.repeat_interleave(key, num_repeat, dim=1)
+            value = torch.repeat_interleave(value, num_repeat, dim=1)
+
+        return query, key, value
+
+    def _forward_sdpa(
+        self,
+        query: torch.Tensor,
+        key: torch.Tensor,
+        value: torch.Tensor,
+        cu_seqlens: torch.Tensor | None = None,
+    ) -> torch.Tensor:
+        # TODO(Isotr0py): Migrate MultiHeadAttention
+        assert cu_seqlens is not None
+
+        bsz, q_len = query.size()[:2]
+        kv_len = key.size(1)
+
+        query, key, value = self.reshape_qkv_to_4d(
+            query, key, value, bsz, q_len, kv_len
+        )
+
+        output = vit_torch_sdpa_wrapper(
+            q=query,
+            k=key,
+            v=value,
+            cu_seqlens=cu_seqlens,
+        )
+        return output
+
+    def _forward_fa(
+        self,
+        query: torch.Tensor,
+        key: torch.Tensor,
+        value: torch.Tensor,
+        cu_seqlens: torch.Tensor | None = None,
+        max_seqlen: torch.Tensor | None = None,  # Only used for Flash Attention
+    ) -> torch.Tensor:
+        assert self.flash_attn_varlen_func is not None, (
+            "Flash attention function is not set."
+        )
+        # # TODO(Isotr0py): Migrate MultiHeadAttention
+        assert cu_seqlens is not None and max_seqlen is not None
+
+        bsz = query.shape[0]
+
+        output = vit_flash_attn_wrapper(
+            q=query,
+            k=key,
+            v=value,
+            cu_seqlens=cu_seqlens,
+            max_seqlen=max_seqlen,
+            batch_size=bsz,
+            is_rocm_aiter=(self.attn_backend == AttentionBackendEnum.ROCM_AITER_FA),
+        )
+        return output
+
+    def forward_native(
+        self,
+        query: torch.Tensor,
+        key: torch.Tensor,
+        value: torch.Tensor,
+        cu_seqlens: torch.Tensor | None = None,
+        max_seqlen: torch.Tensor | None = None,  # Only used for Flash Attention
+    ) -> torch.Tensor:
+        return self._forward_sdpa(query, key, value, cu_seqlens)
+
+    def forward_cuda(
+        self,
+        query: torch.Tensor,
+        key: torch.Tensor,
+        value: torch.Tensor,
+        cu_seqlens: torch.Tensor | None = None,
+        max_seqlen: torch.Tensor | None = None,  # Only used for Flash Attention
+    ) -> torch.Tensor:
+        if self.is_flash_attn_backend:
+            return self._forward_fa(query, key, value, cu_seqlens, max_seqlen)
+        elif self.attn_backend == AttentionBackendEnum.TORCH_SDPA:
+            return self._forward_sdpa(query, key, value, cu_seqlens)
+        else:
+            raise ValueError(
+                f"Unsupported multi-modal encoder attention backend for CUDA: "
+                f"{self.attn_backend}."
+            )
+
+    def forward_cpu(
+        self,
+        query: torch.Tensor,
+        key: torch.Tensor,
+        value: torch.Tensor,
+        cu_seqlens: torch.Tensor | None = None,
+        max_seqlen: torch.Tensor | None = None,  # Only used for Flash Attention
+    ) -> torch.Tensor:
+        return self._forward_sdpa(query, key, value, cu_seqlens)
+
+    def forward_xpu(
+        self,
+        query: torch.Tensor,
+        key: torch.Tensor,
+        value: torch.Tensor,
+        cu_seqlens: torch.Tensor | None = None,
+        max_seqlen: torch.Tensor | None = None,  # Only used for Flash Attention
+    ) -> torch.Tensor:
+        assert self.is_flash_attn_backend, (
+            "XPU only supports FLASH_ATTN for vision attention."
+        )
+        return self._forward_fa(query, key, value, cu_seqlens, max_seqlen)
+
+    def forward_tpu(
+        self,
+        query: torch.Tensor,
+        key: torch.Tensor,
+        value: torch.Tensor,
+        cu_seqlens: torch.Tensor | None = None,
+        max_seqlen: torch.Tensor | None = None,  # Only used for Flash Attention
+    ) -> torch.Tensor:
+        assert self.attn_backend == AttentionBackendEnum.PALLAS, (
+            f"MMEncoderAttention on TPU only supports PALLAS backend, "
+            f"but got {self.attn_backend}."
+        )
+        if cu_seqlens is None:
+            query, key, value = (x.transpose(1, 2) for x in (query, key, value))
+            from torch_xla.experimental.custom_kernel import flash_attention
+
+            out = flash_attention(query, key, value, sm_scale=self.scale)
+            out = out.transpose(1, 2)
+            return out
+        logger.warning_once(
+            "PALLAS backend with cu_seqlens is not supported for ViT yet. ",
+            "Falling back to SDPA implementation.",
+        )
+        return self._forward_sdpa(query, key, value, cu_seqlens)

vllm/attention/ops/vit_attn_wrappers.py

@@ -44,9 +44,7 @@ def flash_attn_maxseqlen_wrapper(
         dropout_p=0.0,
         causal=False,
     )
-    context_layer = einops.rearrange(
+    context_layer = einops.rearrange(output, "(b s) h d -> b s h d", b=batch_size)
-        output, "(b s) h d -> s b (h d)", b=batch_size
-    ).contiguous()
     return context_layer
 
 
@@ -59,8 +57,7 @@ def flash_attn_maxseqlen_wrapper_fake(
     batch_size: int,
     is_rocm_aiter: bool,
 ) -> torch.Tensor:
-    b, s, h, d = q.shape
+    return torch.empty_like(q)
-    return torch.empty((s, b, h * d), dtype=q.dtype, device=q.device)
 
 
 direct_register_custom_op(
@@ -106,7 +103,6 @@ def torch_sdpa_wrapper(
         output_i = einops.rearrange(output_i, "b h s d -> b s h d ")
         outputs.append(output_i)
     context_layer = torch.cat(outputs, dim=1)
-    context_layer = einops.rearrange(context_layer, "b s h d -> s b (h d)").contiguous()
     return context_layer
 
 
@@ -116,8 +112,7 @@ def torch_sdpa_wrapper_fake(
     v: torch.Tensor,
     cu_seqlens: torch.Tensor,
 ) -> torch.Tensor:
-    b, s, h, d = q.shape
+    return torch.empty_like(q)
-    return torch.empty((s, b, h * d), dtype=q.dtype, device=q.device)
 
 
 direct_register_custom_op(

vllm/model_executor/models/dots_ocr.py

@@ -5,15 +5,14 @@ from typing import Annotated, Literal, TypeAlias
 
 import torch
 import torch.nn as nn
-import torch.nn.functional as F
 from torch.nn import LayerNorm
 from transformers.models.qwen2_vl import Qwen2VLProcessor
 
 from vllm.attention.backends.registry import AttentionBackendEnum
-from vllm.attention.layer import (
+from vllm.attention.layers.mm_encoder_attention import (
-    maybe_get_vit_flash_attn_backend,
+    MMEncoderAttention,
 )
-from vllm.config import VllmConfig
+from vllm.config import MultiModalConfig, VllmConfig
 from vllm.config.multimodal import BaseDummyOptions
 from vllm.distributed import utils as dist_utils
 from vllm.distributed.parallel_state import (
@@ -254,11 +253,15 @@ class DotsVisionAttention(nn.Module):
         bias: bool = True,
         *,
         quant_config: QuantizationConfig | None = None,
+        multimodal_config: MultiModalConfig | None = None,
         prefix: str = "",
-        use_data_parallel: bool = False,
-        attn_backend_override: AttentionBackendEnum | None = None,
     ) -> None:
         super().__init__()
+        use_data_parallel = (
+            multimodal_config.mm_encoder_tp_mode == "data"
+            if multimodal_config
+            else False
+        )
 
         self.embed_dim = dim
         self.tp_size = (
@@ -287,31 +290,13 @@ class DotsVisionAttention(nn.Module):
             prefix=f"{prefix}.proj",
             disable_tp=use_data_parallel,
         )
-        # Select attention backend
-        self.attn_backend = get_vit_attn_backend(
-            self.hidden_size_per_attention_head,
-            torch.get_default_dtype(),
-            attn_backend_override=attn_backend_override,
-        )
 
-        self.attn_backend, self.flash_attn_varlen_func = (
+        self.attn = MMEncoderAttention(
-            maybe_get_vit_flash_attn_backend(
+            num_heads=self.num_attention_heads_per_partition,
-                self.attn_backend,
+            head_size=self.hidden_size_per_attention_head,
-                attn_backend_override=attn_backend_override,
+            multimodal_config=multimodal_config,
-            )
+            prefix=f"{prefix}.attn",
         )
-        if self.attn_backend not in {
-            AttentionBackendEnum.FLASH_ATTN,
-            AttentionBackendEnum.TORCH_SDPA,
-            AttentionBackendEnum.ROCM_AITER_FA,
-        }:
-            raise RuntimeError(
-                f"Unsupported vision attention backend: {self.attn_backend}"
-            )
-        self.is_flash_attn_backend = self.attn_backend in {
-            AttentionBackendEnum.FLASH_ATTN,
-            AttentionBackendEnum.ROCM_AITER_FA,
-        }
 
     def forward(
         self,
@@ -319,7 +304,7 @@ class DotsVisionAttention(nn.Module):
         cu_seqlens: torch.Tensor,
         rotary_pos_emb: torch.Tensor | None = None,
         *,
-        max_seqlen: int | None = None,
+        max_seqlen: torch.Tensor | None = None,
     ) -> torch.Tensor:
         # [S, C] -> [S, B=1, C]
         x = hidden_states.unsqueeze(1)
@@ -336,41 +321,13 @@ class DotsVisionAttention(nn.Module):
             qk_rotated = apply_rotary_pos_emb_vision(qk_concat, rotary_pos_emb)
             q, k = torch.chunk(qk_rotated, 2, dim=0)
 
-        if self.is_flash_attn_backend:
+        context_layer = self.attn(
-            q_ = q.reshape(bs * q.shape[1], q.shape[2], q.shape[3])
+            query=q,
-            k_ = k.reshape(bs * k.shape[1], k.shape[2], k.shape[3])
+            key=k,
-            v_ = v.reshape(bs * v.shape[1], v.shape[2], v.shape[3])
+            value=v,
-            output = self.flash_attn_varlen_func(
+            cu_seqlens=cu_seqlens,
-                q_,
+            max_seqlen=max_seqlen,
-                k_,
+        )
-                v_,
-                cu_seqlens_q=cu_seqlens,
-                cu_seqlens_k=cu_seqlens,
-                max_seqlen_q=max_seqlen,
-                max_seqlen_k=max_seqlen,
-                dropout_p=0.0,
-                causal=False,
-            )
-            context_layer = output.view(
-                bs,
-                -1,
-                self.num_attention_heads_per_partition,
-                self.hidden_size_per_attention_head,
-            )
-        elif self.attn_backend == AttentionBackendEnum.TORCH_SDPA:
-            outputs = []
-            for i in range(1, len(cu_seqlens)):
-                s = int(cu_seqlens[i - 1])
-                e = int(cu_seqlens[i])
-                q_i = q[:, s:e].permute(0, 2, 1, 3)
-                k_i = k[:, s:e].permute(0, 2, 1, 3)
-                v_i = v[:, s:e].permute(0, 2, 1, 3)
-                out_i = F.scaled_dot_product_attention(q_i, k_i, v_i, dropout_p=0.0)
-                out_i = out_i.permute(0, 2, 1, 3)
-                outputs.append(out_i)
-            context_layer = torch.cat(outputs, dim=1) if outputs else q[:, :0]
-        else:
-            raise RuntimeError("Unsupported attention backend")
 
         # [B,S,H,D] -> [S,B,H*D] -> [S, C]
         context_layer = context_layer.permute(1, 0, 2, 3).contiguous()
@@ -385,14 +342,19 @@ class DotsSwiGLUFFN(nn.Module):
         config,
         *,
         quant_config: QuantizationConfig | None = None,
+        multimodal_config: MultiModalConfig | None = None,
         prefix: str = "",
-        use_data_parallel: bool = False,
     ):
         super().__init__()
         hidden_features = config.intermediate_size
         in_features = config.embed_dim
         bias = config.use_bias
 
+        use_data_parallel = (
+            multimodal_config.mm_encoder_tp_mode == "data"
+            if multimodal_config
+            else False
+        )
         # Referenced aimv2.py AIMv2SwiGLUFFN
         self.fc13 = MergedColumnParallelLinear(
             in_features,
@@ -498,9 +460,8 @@ class DotsVisionBlock(nn.Module):
         config,
         *,
         quant_config: QuantizationConfig | None = None,
+        multimodal_config: MultiModalConfig | None = None,
         prefix: str = "",
-        use_data_parallel: bool = False,
-        attn_backend_override: AttentionBackendEnum | None = None,
     ):
         super().__init__()
 
@@ -510,16 +471,15 @@ class DotsVisionBlock(nn.Module):
             num_heads=config.num_attention_heads,
             bias=config.use_bias,
             quant_config=quant_config,
+            multimodal_config=multimodal_config,
             prefix=f"{prefix}.attn",
-            use_data_parallel=use_data_parallel,
-            attn_backend_override=attn_backend_override,
         )
         self.norm1 = RMSNorm(config.embed_dim, eps=config.rms_norm_eps)
         self.mlp = DotsSwiGLUFFN(
             config,
             quant_config=quant_config,
+            multimodal_config=multimodal_config,
             prefix=f"{prefix}.mlp",
-            use_data_parallel=use_data_parallel,
         )
         self.norm2 = RMSNorm(config.embed_dim, eps=config.rms_norm_eps)
 
@@ -546,12 +506,11 @@ class DotsVisionTransformer(nn.Module):
         self,
         config: DotsVisionConfig,
         quant_config: QuantizationConfig | None = None,
+        multimodal_config: MultiModalConfig | None = None,
         *,
         num_hidden_layers_override: int | None = None,
         require_post_norm: bool | None = None,
         prefix: str = "",
-        use_data_parallel: bool = False,
-        attn_backend_override: AttentionBackendEnum | None = None,
     ) -> None:
         super().__init__()
         self.config = config
@@ -561,6 +520,11 @@ class DotsVisionTransformer(nn.Module):
 
         head_dim = config.embed_dim // config.num_attention_heads
         self.rotary_pos_emb = VisionRotaryEmbedding(head_dim // 2)
+        attn_backend_override = (
+            multimodal_config.mm_encoder_attn_backend
+            if multimodal_config is not None
+            else None
+        )
         self.attn_backend = get_vit_attn_backend(
             head_size=head_dim,
             dtype=torch.get_default_dtype(),
@@ -578,9 +542,8 @@ class DotsVisionTransformer(nn.Module):
                 DotsVisionBlock(
                     config,
                     quant_config=quant_config,
+                    multimodal_config=multimodal_config,
                     prefix=f"{prefix}.blocks.{i}",
-                    use_data_parallel=use_data_parallel,
-                    attn_backend_override=attn_backend_override,
                 )
                 for i in range(num_layers)
             ]
@@ -592,6 +555,11 @@ class DotsVisionTransformer(nn.Module):
         else:
             self.post_trunk_norm = None
 
+        use_data_parallel = (
+            multimodal_config.mm_encoder_tp_mode == "data"
+            if multimodal_config
+            else False
+        )
         self.merger = PatchMerger(
             dim=config.hidden_size,
             context_dim=config.embed_dim,
@@ -647,7 +615,7 @@ class DotsVisionTransformer(nn.Module):
             self.attn_backend == AttentionBackendEnum.FLASH_ATTN
             or self.attn_backend == AttentionBackendEnum.ROCM_AITER_FA
         ):
-            max_seqlen = (cu_seqlens[1:] - cu_seqlens[:-1]).max().item()
+            max_seqlen = (cu_seqlens[1:] - cu_seqlens[:-1]).max()
         return max_seqlen
 
     def forward(
@@ -733,17 +701,12 @@ class DotsOCRForCausalLM(nn.Module, SupportsMultiModal, SupportsPP, SupportsLoRA
             self.config.vision_config = vision_config
         else:
             vision_config = self.config.vision_config
-        attn_backend_override = (
+
-            multimodal_config.mm_encoder_attn_backend
-            if multimodal_config is not None
-            else None
-        )
         self.vision_tower = DotsVisionTransformer(
             vision_config,
             quant_config=self.quant_config,
+            multimodal_config=multimodal_config,
             prefix=maybe_prefix(prefix, "vision_tower"),
-            use_data_parallel=self.use_data_parallel,
-            attn_backend_override=attn_backend_override,
         )
         self.language_model: Qwen2ForCausalLM = init_vllm_registered_model(
             vllm_config=vllm_config,

vllm/model_executor/models/ernie45_vl.py

@@ -37,10 +37,10 @@ from einops import rearrange, repeat
 from transformers import BatchFeature
 
 from vllm.attention.backends.registry import AttentionBackendEnum
-from vllm.attention.layer import (
+from vllm.attention.layers.mm_encoder_attention import (
-    maybe_get_vit_flash_attn_backend,
+    MMEncoderAttention,
 )
-from vllm.config import VllmConfig
+from vllm.config import MultiModalConfig, VllmConfig
 from vllm.config.multimodal import BaseDummyOptions
 from vllm.distributed import parallel_state
 from vllm.distributed import utils as dist_utils
@@ -163,8 +163,8 @@ class Ernie4_5_VisionAttention(nn.Module):
         num_heads: int,
         projection_size: int,
         quant_config: QuantizationConfig | None = None,
+        multimodal_config: MultiModalConfig | None = None,
         prefix: str = "",
-        attn_backend_override: AttentionBackendEnum | None = None,
     ) -> None:
         super().__init__()
         # Per attention head and per partition values.
@@ -193,33 +193,13 @@ class Ernie4_5_VisionAttention(nn.Module):
             prefix=f"{prefix}.proj",
         )
 
-        # Detect attention implementation.
+        self.attn = MMEncoderAttention(
-        self.attn_backend = get_vit_attn_backend(
+            num_heads=self.num_attention_heads_per_partition,
             head_size=self.hidden_size_per_attention_head,
-            dtype=torch.get_default_dtype(),
+            multimodal_config=multimodal_config,
-            attn_backend_override=attn_backend_override,
+            prefix=f"{prefix}.attn",
         )
 
-        self.attn_backend, self.flash_attn_varlen_func = (
-            maybe_get_vit_flash_attn_backend(
-                self.attn_backend,
-                attn_backend_override=attn_backend_override,
-            )
-        )
-
-        if self.attn_backend not in {
-            AttentionBackendEnum.FLASH_ATTN,
-            AttentionBackendEnum.TORCH_SDPA,
-            AttentionBackendEnum.ROCM_AITER_FA,
-        }:
-            raise RuntimeError(
-                f"Ernie45-VL does not support {self.attn_backend} backend now."
-            )
-        self.is_flash_attn_backend = self.attn_backend in {
-            AttentionBackendEnum.FLASH_ATTN,
-            AttentionBackendEnum.ROCM_AITER_FA,
-        }
-
     def split_qkv(self, qkv: torch.Tensor) -> tuple[torch.Tensor, ...]:
         # [s, b, 3 * head * head_dim]
         seq_len, bs, _ = qkv.shape
@@ -253,14 +233,13 @@ class Ernie4_5_VisionAttention(nn.Module):
         x: torch.Tensor,
         cu_seqlens: torch.Tensor,
         rotary_pos_emb: torch.Tensor,
-        max_seqlen: int | None = None,  # Only used for Flash Attention
+        max_seqlen: torch.Tensor | None = None,  # Only used for Flash Attention
     ) -> torch.Tensor:
         # [s, b, c] --> [s, b, head * 3 * head_dim]
         x, _ = self.qkv(x)
 
         # [s, b, 3 * head * head_dim] -> 3 * [s, b, head, head_dim]
         q, k, v = self.split_qkv(x)
-        batch_size = q.shape[1]
 
         q, k, v = (rearrange(x, "s b ... -> b s ...").contiguous() for x in (q, k, v))
         if rotary_pos_emb is not None:
@@ -268,43 +247,14 @@ class Ernie4_5_VisionAttention(nn.Module):
             qk_rotated = apply_rotary_pos_emb_vision(qk_concat, rotary_pos_emb)
             q, k = torch.chunk(qk_rotated, 2, dim=0)
 
-        if self.is_flash_attn_backend:
+        output = self.attn(
-            q, k, v = (rearrange(x, "b s ... -> (b s) ...") for x in [q, k, v])
+            query=q,
-
+            key=k,
-            output = self.flash_attn_varlen_func(
+            value=v,
-                q,
+            cu_seqlens=cu_seqlens,
-                k,
+            max_seqlen=max_seqlen,
-                v,
+        )
-                cu_seqlens_q=cu_seqlens,
+        context_layer = rearrange(output, "b s h d -> s b (h d)").contiguous()
-                cu_seqlens_k=cu_seqlens,
-                max_seqlen_q=max_seqlen,
-                max_seqlen_k=max_seqlen,
-                dropout_p=0.0,
-                causal=False,
-            )
-
-            context_layer = rearrange(
-                output, "(b s) h d -> s b (h d)", b=batch_size
-            ).contiguous()
-        elif self.attn_backend == AttentionBackendEnum.TORCH_SDPA:
-            # Execute attention entry by entry for speed & less VRAM.
-            outputs = []
-
-            lens = (cu_seqlens[1:] - cu_seqlens[:-1]).tolist()
-            q_chunks = torch.split(q, lens, dim=1)
-            k_chunks = torch.split(k, lens, dim=1)
-            v_chunks = torch.split(v, lens, dim=1)
-            for q_i, k_i, v_i in zip(q_chunks, k_chunks, v_chunks):
-                q_i, k_i, v_i = (
-                    rearrange(x, "b s h d -> b h s d") for x in [q_i, k_i, v_i]
-                )
-                output_i = F.scaled_dot_product_attention(q_i, k_i, v_i, dropout_p=0.0)
-                output_i = rearrange(output_i, "b h s d -> b s h d ")
-                outputs.append(output_i)
-            context_layer = torch.cat(outputs, dim=1)
-            context_layer = rearrange(
-                context_layer, "b s h d -> s b (h d)"
-            ).contiguous()
 
         output, _ = self.proj(context_layer)
         return output
@@ -350,8 +300,8 @@ class Ernie4_5_VisionBlock(nn.Module):
         act_layer: type[nn.Module] = QuickGELU,
         norm_layer: Callable[[int], nn.Module] | None = None,
         quant_config: QuantizationConfig | None = None,
+        multimodal_config: MultiModalConfig | None = None,
         prefix: str = "",
-        attn_backend_override: AttentionBackendEnum | None = None,
     ) -> None:
         super().__init__()
 
@@ -366,8 +316,8 @@ class Ernie4_5_VisionBlock(nn.Module):
             num_heads=num_heads,
             projection_size=dim,
             quant_config=quant_config,
+            multimodal_config=multimodal_config,
             prefix=f"{prefix}.attn",
-            attn_backend_override=attn_backend_override,
         )
 
         self.mlp = Ernie4_5_VisionMLP(
@@ -383,7 +333,7 @@ class Ernie4_5_VisionBlock(nn.Module):
         hidden_states: torch.Tensor,
         cu_seqlens: torch.Tensor,
         rotary_pos_emb: torch.Tensor,
-        max_seqlen: int | None = None,  # Only used for Flash Attention
+        max_seqlen: torch.Tensor | None = None,  # Only used for Flash Attention
     ) -> torch.Tensor:
         hidden_states = hidden_states + self.attn(
             self.norm1(hidden_states),
@@ -441,8 +391,8 @@ class Ernie4_5_VisionTransformer(nn.Module):
         vision_config,
         norm_eps: float = 1e-6,
         quant_config: QuantizationConfig | None = None,
+        multimodal_config: MultiModalConfig | None = None,
         prefix: str = "",
-        attn_backend_override: AttentionBackendEnum | None = None,
     ) -> None:
         super().__init__()
         patch_size = vision_config.patch_size
@@ -477,8 +427,8 @@ class Ernie4_5_VisionTransformer(nn.Module):
                     mlp_ratio=mlp_ratio,
                     norm_layer=norm_layer,
                     quant_config=quant_config,
+                    multimodal_config=multimodal_config,
                     prefix=f"{prefix}.blocks.{layer_idx}",
-                    attn_backend_override=attn_backend_override,
                 )
                 for layer_idx in range(depth)
             ]
@@ -489,6 +439,9 @@ class Ernie4_5_VisionTransformer(nn.Module):
         )
         self.ln = nn.LayerNorm(hidden_size, eps=1e-6)
 
+        attn_backend_override = (
+            multimodal_config.mm_encoder_attn_backend if multimodal_config else None
+        )
         self.attn_backend = get_vit_attn_backend(
             head_size=head_dim,
             dtype=torch.get_default_dtype(),
@@ -535,13 +488,13 @@ class Ernie4_5_VisionTransformer(nn.Module):
         rotary_pos_emb = rotary_pos_emb_full[pos_ids].flatten(1)
         return rotary_pos_emb
 
-    def compute_attn_mask_seqlen(self, cu_seqlens: torch.Tensor) -> int | None:
+    def compute_attn_mask_seqlen(self, cu_seqlens: torch.Tensor) -> torch.Tensor | None:
         max_seqlen = None
         if (
             self.attn_backend == AttentionBackendEnum.FLASH_ATTN
             or self.attn_backend == AttentionBackendEnum.ROCM_AITER_FA
         ):
-            max_seqlen = (cu_seqlens[1:] - cu_seqlens[:-1]).max().item()
+            max_seqlen = (cu_seqlens[1:] - cu_seqlens[:-1]).max()
         return max_seqlen
 
     def forward(
@@ -1304,17 +1257,12 @@ class Ernie4_5_VLMoeForConditionalGeneration(
         self.config = config
         self.multimodal_config = multimodal_config
 
-        attn_backend_override = (
-            multimodal_config.mm_encoder_attn_backend
-            if multimodal_config is not None
-            else None
-        )
         self.vision_model = Ernie4_5_VisionTransformer(
             config.vision_config,
             norm_eps=getattr(config, "rms_norm_eps", 1e-6),
             quant_config=quant_config,
+            multimodal_config=multimodal_config,
             prefix=maybe_prefix(prefix, "vision_model"),
-            attn_backend_override=attn_backend_override,
         )
 
         self.language_model = Ernie4_5_VLMoeForCausalLM(

vllm/model_executor/models/glm4_1v.py

@@ -47,8 +47,10 @@ from transformers.models.glm4v.video_processing_glm4v import Glm4vVideoProcessor
 from transformers.video_utils import VideoMetadata
 
 from vllm.attention.backends.registry import AttentionBackendEnum
-from vllm.attention.layer import maybe_get_vit_flash_attn_backend
+from vllm.attention.layers.mm_encoder_attention import (
-from vllm.config import VllmConfig
+    MMEncoderAttention,
+)
+from vllm.config import MultiModalConfig, VllmConfig
 from vllm.config.multimodal import BaseDummyOptions, VideoDummyOptions
 from vllm.distributed import get_tensor_model_parallel_world_size, parallel_state
 from vllm.distributed import utils as dist_utils
@@ -191,10 +193,15 @@ class Glm4vVisionMLP(nn.Module):
         hidden_features: int,
         bias: bool = False,
         quant_config: QuantizationConfig | None = None,
+        multimodal_config: MultiModalConfig | None = None,
         prefix: str = "",
-        use_data_parallel: bool = False,
     ):
         super().__init__()
+        use_data_parallel = (
+            multimodal_config.mm_encoder_tp_mode == "data"
+            if multimodal_config
+            else False
+        )
         self.gate_up_proj = MergedColumnParallelLinear(
             input_size=in_features,
             output_sizes=[hidden_features] * 2,
@@ -248,12 +255,16 @@ class Glm4vVisionAttention(nn.Module):
         num_heads: int,
         projection_size: int,
         quant_config: QuantizationConfig | None = None,
+        multimodal_config: MultiModalConfig | None = None,
         prefix: str = "",
-        use_data_parallel: bool = False,
-        attn_backend_override: AttentionBackendEnum | None = None,
     ) -> None:
         super().__init__()
         # Per attention head and per partition values.
+        use_data_parallel = (
+            multimodal_config.mm_encoder_tp_mode == "data"
+            if multimodal_config
+            else False
+        )
         self.tp_size = (
             1 if use_data_parallel else get_tensor_model_parallel_world_size()
         )
@@ -287,34 +298,12 @@ class Glm4vVisionAttention(nn.Module):
             disable_tp=use_data_parallel,
         )
 
-        # Detect attention implementation.
+        self.attn = MMEncoderAttention(
-        self.attn_backend = get_vit_attn_backend(
+            num_heads=self.num_attention_heads_per_partition,
             head_size=self.hidden_size_per_attention_head,
-            dtype=torch.get_default_dtype(),
+            multimodal_config=multimodal_config,
-            attn_backend_override=attn_backend_override,
         )
 
-        self.attn_backend, self.flash_attn_varlen_func = (
-            maybe_get_vit_flash_attn_backend(
-                self.attn_backend,
-                attn_backend_override=attn_backend_override,
-            )
-        )
-
-        if self.attn_backend not in {
-            AttentionBackendEnum.FLASH_ATTN,
-            AttentionBackendEnum.TORCH_SDPA,
-            AttentionBackendEnum.ROCM_AITER_FA,
-        }:
-            raise RuntimeError(
-                f"GLM-4V does not support {self.attn_backend} backend now."
-            )
-
-        self.is_flash_attn_backend = self.attn_backend in {
-            AttentionBackendEnum.FLASH_ATTN,
-            AttentionBackendEnum.ROCM_AITER_FA,
-        }
-
     def split_qkv(self, qkv: torch.Tensor) -> tuple[torch.Tensor, ...]:
         # [s, b, 3 * head * head_dim]
         seq_len, bs, _ = qkv.shape
@@ -338,14 +327,13 @@ class Glm4vVisionAttention(nn.Module):
         cu_seqlens: torch.Tensor,
         rotary_pos_emb_cos: torch.Tensor,
         rotary_pos_emb_sin: torch.Tensor,
-        max_seqlen: int | None = None,  # Only used for Flash Attention
+        max_seqlen: torch.Tensor | None = None,  # Only used for Flash Attention
     ) -> torch.Tensor:
         # [s, b, c] --> [s, b, head * 3 * head_dim]
         x, _ = self.qkv(x)
 
         # [s, b, 3 * head * head_dim] -> 3 * [s, b, head, head_dim]
         q, k, v = self.split_qkv(x)
-        batch_size = q.shape[1]
 
         q, k, v = (rearrange(x, "s b ... -> b s ...").contiguous() for x in (q, k, v))
         if rotary_pos_emb_cos is not None and rotary_pos_emb_sin is not None:
@@ -356,43 +344,14 @@ class Glm4vVisionAttention(nn.Module):
             )
             q, k = torch.chunk(qk_rotated, 2, dim=0)
 
-        if self.is_flash_attn_backend:
+        context_layer = self.attn(
-            q, k, v = (rearrange(x, "b s ... -> (b s) ...") for x in [q, k, v])
+            query=q,
-
+            key=k,
-            output = self.flash_attn_varlen_func(
+            value=v,
-                q,
+            cu_seqlens=cu_seqlens,
-                k,
+            max_seqlen=max_seqlen,
-                v,
+        )
-                cu_seqlens_q=cu_seqlens,
+        context_layer = rearrange(context_layer, "b s h d -> s b (h d)").contiguous()
-                cu_seqlens_k=cu_seqlens,
-                max_seqlen_q=max_seqlen,
-                max_seqlen_k=max_seqlen,
-                dropout_p=0.0,
-                causal=False,
-            )
-
-            context_layer = rearrange(
-                output, "(b s) h d -> s b (h d)", b=batch_size
-            ).contiguous()
-        elif self.attn_backend == AttentionBackendEnum.TORCH_SDPA:
-            # Execute attention entry by entry for speed & less VRAM.
-            outputs = []
-
-            lens = (cu_seqlens[1:] - cu_seqlens[:-1]).tolist()
-            q_chunks = torch.split(q, lens, dim=1)
-            k_chunks = torch.split(k, lens, dim=1)
-            v_chunks = torch.split(v, lens, dim=1)
-            for q_i, k_i, v_i in zip(q_chunks, k_chunks, v_chunks):
-                q_i, k_i, v_i = (
-                    rearrange(x, "b s h d -> b h s d") for x in [q_i, k_i, v_i]
-                )
-                output_i = F.scaled_dot_product_attention(q_i, k_i, v_i, dropout_p=0.0)
-                output_i = rearrange(output_i, "b h s d -> b s h d ")
-                outputs.append(output_i)
-            context_layer = torch.cat(outputs, dim=1)
-            context_layer = rearrange(
-                context_layer, "b s h d -> s b (h d)"
-            ).contiguous()
 
         output, _ = self.proj(context_layer)
         return output
@@ -406,9 +365,8 @@ class Glm4vVisionBlock(nn.Module):
         mlp_hidden_dim: int,
         norm_layer: Callable[[int], nn.Module] | None = None,
         quant_config: QuantizationConfig | None = None,
+        multimodal_config: MultiModalConfig | None = None,
         prefix: str = "",
-        use_data_parallel: bool = False,
-        attn_backend_override: AttentionBackendEnum | None = None,
     ) -> None:
         super().__init__()
         if norm_layer is None:
@@ -420,17 +378,16 @@ class Glm4vVisionBlock(nn.Module):
             num_heads=num_heads,
             projection_size=dim,
             quant_config=quant_config,
+            multimodal_config=multimodal_config,
             prefix=f"{prefix}.attn",
-            use_data_parallel=use_data_parallel,
-            attn_backend_override=attn_backend_override,
         )
         self.mlp = Glm4vVisionMLP(
             dim,
             mlp_hidden_dim,
             bias=False,
             quant_config=quant_config,
+            multimodal_config=multimodal_config,
             prefix=f"{prefix}.mlp",
-            use_data_parallel=use_data_parallel,
         )
 
     def forward(
@@ -489,11 +446,16 @@ class Glm4vPatchMerger(nn.Module):
         d_model: int,
         context_dim: int,
         quant_config: QuantizationConfig | None = None,
+        multimodal_config: MultiModalConfig | None = None,
         bias: bool = False,
         prefix: str = "",
-        use_data_parallel: bool = False,
     ) -> None:
         super().__init__()
+        use_data_parallel = (
+            multimodal_config.mm_encoder_tp_mode == "data"
+            if multimodal_config
+            else False
+        )
         self.hidden_size = d_model
         self.proj = ColumnParallelLinear(
             self.hidden_size,
@@ -649,19 +611,19 @@ class Glm4vVisionTransformer(nn.Module):
         vision_config: Glm4vVisionConfig,
         norm_eps: float = 1e-6,
         quant_config: QuantizationConfig | None = None,
+        multimodal_config: MultiModalConfig | None = None,
         prefix: str = "",
-        use_data_parallel: bool = False,
-        attn_backend_override: AttentionBackendEnum | None = None,
     ) -> None:
         super().__init__()
 
+        assert multimodal_config is not None, "multimodal_config must be provided"
+
         patch_size = vision_config.patch_size
         temporal_patch_size = vision_config.temporal_patch_size
         in_channels = vision_config.in_channels
         depth = vision_config.depth
         self.hidden_size = vision_config.hidden_size
         self.num_heads = vision_config.num_heads
-        self.use_data_parallel = use_data_parallel
 
         self.patch_size = vision_config.patch_size
         self.spatial_merge_size = vision_config.spatial_merge_size
@@ -690,9 +652,8 @@ class Glm4vVisionTransformer(nn.Module):
                     mlp_hidden_dim=vision_config.out_hidden_size,
                     norm_layer=norm_layer,
                     quant_config=quant_config,
+                    multimodal_config=multimodal_config,
                     prefix=f"{prefix}.blocks.{layer_idx}",
-                    use_data_parallel=self.use_data_parallel,
-                    attn_backend_override=attn_backend_override,
                 )
                 for layer_idx in range(depth)
             ]
@@ -701,9 +662,9 @@ class Glm4vVisionTransformer(nn.Module):
             d_model=vision_config.out_hidden_size,
             context_dim=vision_config.intermediate_size,
             quant_config=quant_config,
+            multimodal_config=multimodal_config,
             bias=False,
             prefix=f"{prefix}.merger",
-            use_data_parallel=self.use_data_parallel,
         )
         self.embeddings = Glm4vVisionEmbeddings(vision_config)
 
@@ -723,7 +684,7 @@ class Glm4vVisionTransformer(nn.Module):
         self.attn_backend = get_vit_attn_backend(
             head_size=head_dim,
             dtype=torch.get_default_dtype(),
-            attn_backend_override=attn_backend_override,
+            attn_backend_override=multimodal_config.mm_encoder_attn_backend,
         )
 
     @property
@@ -775,13 +736,13 @@ class Glm4vVisionTransformer(nn.Module):
     def compute_attn_mask_seqlen(
         self,
         cu_seqlens: torch.Tensor,
-    ) -> int | None:
+    ) -> torch.Tensor | None:
         max_seqlen = None
         if (
             self.attn_backend == AttentionBackendEnum.FLASH_ATTN
             or self.attn_backend == AttentionBackendEnum.ROCM_AITER_FA
         ):
-            max_seqlen = (cu_seqlens[1:] - cu_seqlens[:-1]).max().item()
+            max_seqlen = (cu_seqlens[1:] - cu_seqlens[:-1]).max()
         return max_seqlen
 
     def forward(
@@ -1465,18 +1426,12 @@ class Glm4vForConditionalGeneration(
         self.multimodal_config = multimodal_config
         self.use_data_parallel = multimodal_config.mm_encoder_tp_mode == "data"
 
-        attn_backend_override = (
-            multimodal_config.mm_encoder_attn_backend
-            if multimodal_config is not None
-            else None
-        )
         self.visual = Glm4vVisionTransformer(
             config.vision_config,
             norm_eps=getattr(config, "rms_norm_eps", 1e-5),
             quant_config=quant_config,
+            multimodal_config=multimodal_config,
             prefix=maybe_prefix(prefix, "visual"),
-            use_data_parallel=self.use_data_parallel,
-            attn_backend_override=attn_backend_override,
         )
 
         if config.model_type == "glm4v":

vllm/model_executor/models/keye.py

@@ -9,7 +9,6 @@ from typing import Annotated, Any, Literal, TypeAlias, TypeVar
 import numpy as np
 import torch
 import torch.nn as nn
-import torch.nn.functional as F
 from einops import rearrange
 from transformers import PretrainedConfig
 from transformers.activations import GELUActivation
@@ -17,11 +16,10 @@ from transformers.feature_extraction_utils import BatchFeature
 from transformers.modeling_outputs import BaseModelOutput, BaseModelOutputWithPooling
 from transformers.utils import torch_int
 
-from vllm.attention.backends.registry import AttentionBackendEnum
+from vllm.attention.layers.mm_encoder_attention import (
-from vllm.attention.layer import (
+    MMEncoderAttention,
-    maybe_get_vit_flash_attn_backend,
 )
-from vllm.config import VllmConfig
+from vllm.config import MultiModalConfig, VllmConfig
 from vllm.config.multimodal import BaseDummyOptions
 from vllm.distributed import get_tensor_model_parallel_world_size
 from vllm.logger import init_logger
@@ -80,7 +78,6 @@ from .utils import (
     is_pp_missing_parameter,
     maybe_prefix,
 )
-from .vision import get_vit_attn_backend
 
 logger = init_logger(__name__)
 
@@ -369,8 +366,8 @@ class KeyeSiglipAttention(nn.Module):
         self,
         config: PretrainedConfig,
         quant_config: QuantizationConfig | None = None,
+        multimodal_config: MultiModalConfig | None = None,
         prefix: str = "",
-        attn_backend_override: AttentionBackendEnum | None = None,
     ):
         super().__init__()
         self.config = config
@@ -408,34 +405,14 @@ class KeyeSiglipAttention(nn.Module):
             prefix=f"{prefix}.out_proj",
         )
 
-        # Detect attention implementation.
+        self.attn = MMEncoderAttention(
-        self.attn_backend = get_vit_attn_backend(
+            num_heads=self.num_heads,
             head_size=self.head_dim,
-            dtype=torch.get_default_dtype(),
+            num_kv_heads=self.num_kv_heads,
-            attn_backend_override=attn_backend_override,
+            prefix=f"{prefix}.attn",
+            multimodal_config=multimodal_config,
         )
 
-        self.attn_backend, self.flash_attn_varlen_func = (
-            maybe_get_vit_flash_attn_backend(
-                self.attn_backend,
-                attn_backend_override=attn_backend_override,
-            )
-        )
-
-        if self.attn_backend not in {
-            AttentionBackendEnum.FLASH_ATTN,
-            AttentionBackendEnum.TORCH_SDPA,
-            AttentionBackendEnum.ROCM_AITER_FA,
-        }:
-            raise RuntimeError(
-                f"Keye-VL does not support {self.attn_backend} backend now."
-            )
-
-        self.is_flash_attn_backend = self.attn_backend in {
-            AttentionBackendEnum.FLASH_ATTN,
-            AttentionBackendEnum.ROCM_AITER_FA,
-        }
-
     def forward(
         self,
         hidden_states: torch.Tensor,
@@ -450,8 +427,7 @@ class KeyeSiglipAttention(nn.Module):
             dim=-1,
         )
 
-        max_seqlen = (cu_seqlens[1:] - cu_seqlens[:-1]).max().item()
+        max_seqlen = (cu_seqlens[1:] - cu_seqlens[:-1]).max()
-        batch_size = q.shape[0]
 
         if rope_emb is None:
             q = q.view(*q.shape[:-1], self.num_heads, self.head_dim)
@@ -482,38 +458,14 @@ class KeyeSiglipAttention(nn.Module):
                 self.head_dim,
             )
 
-        if self.is_flash_attn_backend:
+        context_layer = self.attn(
-            q, k, v = (rearrange(x, "b s ... -> (b s) ...") for x in [q, k, v])
+            query=q,
-
+            key=k,
-            output = self.flash_attn_varlen_func(
+            value=v,
-                q,
+            cu_seqlens=cu_seqlens,
-                k,
+            max_seqlen=max_seqlen,
-                v,
+        )
-                cu_seqlens_q=cu_seqlens,
+        context_layer = rearrange(context_layer, "b s h d -> b s (h d)")
-                cu_seqlens_k=cu_seqlens,
-                max_seqlen_q=max_seqlen,
-                max_seqlen_k=max_seqlen,
-                causal=False,
-                softmax_scale=self.scale,
-            )
-            context_layer = rearrange(output, "(b s) ... -> b s ...", b=batch_size)
-        elif self.attn_backend == AttentionBackendEnum.TORCH_SDPA:
-            outputs = []
-            for i in range(1, len(cu_seqlens)):
-                start_idx = cu_seqlens[i - 1]
-                end_idx = cu_seqlens[i]
-                q_i = q[:, start_idx:end_idx]
-                k_i = k[:, start_idx:end_idx]
-                v_i = v[:, start_idx:end_idx]
-                q_i, k_i, v_i = (
-                    rearrange(x, "b s h d -> b h s d") for x in (q_i, k_i, v_i)
-                )
-                output_i = F.scaled_dot_product_attention(q_i, k_i, v_i, dropout_p=0.0)
-                output_i = rearrange(output_i, "b h s d -> b s h d ")
-                outputs.append(output_i)
-            context_layer = torch.cat(outputs, dim=1) if outputs else q[:, :0]
-
-        context_layer = rearrange(context_layer, "b s h d -> b s (h d)").contiguous()
 
         output, _ = self.out_proj(context_layer)
         return output
@@ -547,8 +499,8 @@ class KeyeSiglipEncoderLayer(nn.Module):
         self,
         config: PretrainedConfig,
         quant_config: QuantizationConfig | None = None,
+        multimodal_config: MultiModalConfig | None = None,
         prefix: str = "",
-        attn_backend_override: AttentionBackendEnum | None = None,
     ):
         super().__init__()
         self.embed_dim = config.hidden_size
@@ -556,8 +508,8 @@ class KeyeSiglipEncoderLayer(nn.Module):
         self.self_attn = KeyeSiglipAttention(
             config,
             quant_config=quant_config,
+            multimodal_config=multimodal_config,
             prefix=f"{prefix}.self_attn",
-            attn_backend_override=attn_backend_override,
         )
         self.layer_norm2 = nn.LayerNorm(self.embed_dim, eps=config.layer_norm_eps)
         self.mlp = SiglipMLP(
@@ -601,8 +553,8 @@ class KeyeSiglipEncoder(nn.Module):
         self,
         config: PretrainedConfig,
         quant_config: QuantizationConfig | None = None,
+        multimodal_config: MultiModalConfig | None = None,
         prefix: str = "",
-        attn_backend_override: AttentionBackendEnum | None = None,
     ):
         super().__init__()
         self.config = config
@@ -614,8 +566,8 @@ class KeyeSiglipEncoder(nn.Module):
                 KeyeSiglipEncoderLayer(
                     config,
                     quant_config=quant_config,
+                    multimodal_config=multimodal_config,
                     prefix=f"{prefix}.layers.{layer_idx}",
-                    attn_backend_override=attn_backend_override,
                 )
                 for layer_idx in range(config.num_hidden_layers)
             ]
@@ -696,8 +648,8 @@ class KeyeSiglipVisionTransformer(nn.Module):
         self,
         config: PretrainedConfig,
         quant_config: QuantizationConfig | None = None,
+        multimodal_config: MultiModalConfig | None = None,
         prefix: str = "",
-        attn_backend_override: AttentionBackendEnum | None = None,
     ):
         super().__init__()
         self.config = config
@@ -707,8 +659,8 @@ class KeyeSiglipVisionTransformer(nn.Module):
         self.encoder = KeyeSiglipEncoder(
             config,
             quant_config=quant_config,
+            multimodal_config=multimodal_config,
             prefix=f"{prefix}.encoder",
-            attn_backend_override=attn_backend_override,
         )
         self.post_layernorm = nn.LayerNorm(embed_dim, eps=config.layer_norm_eps)
 
@@ -779,16 +731,16 @@ class KeyeSiglipVisionModel(nn.Module):
         self,
         config: PretrainedConfig,
         quant_config: QuantizationConfig | None = None,
+        multimodal_config: MultiModalConfig | None = None,
         prefix: str = "",
-        attn_backend_override: AttentionBackendEnum | None = None,
     ):
         super().__init__()
 
         self.vision_model = KeyeSiglipVisionTransformer(
             config,
             quant_config=quant_config,
+            multimodal_config=multimodal_config,
             prefix=f"{prefix}.vision_model",
-            attn_backend_override=attn_backend_override,
         )
         self.quant_config = quant_config
 
@@ -1329,16 +1281,11 @@ class BaseKeyeModule(nn.Module):
         self.config = config
         self.multimodal_config = multimodal_config
 
-        attn_backend_override = (
-            multimodal_config.mm_encoder_attn_backend
-            if multimodal_config is not None
-            else None
-        )
         self.visual = KeyeSiglipVisionModel(
             config.vision_config,
             quant_config=quant_config,
+            multimodal_config=multimodal_config,
             prefix=maybe_prefix(prefix, "visual"),
-            attn_backend_override=attn_backend_override,
         )
 
         self.mlp_AR = self._build_projector(

vllm/model_executor/models/opencua.py

@@ -240,18 +240,12 @@ class OpenCUAForConditionalGeneration(Qwen2_5_VLForConditionalGeneration):
         )
 
         if multimodal_config.get_limit_per_prompt("image"):
-            attn_backend_override = (
-                multimodal_config.mm_encoder_attn_backend
-                if multimodal_config is not None
-                else None
-            )
             self.visual = OpenCUAVisionTransformer(
                 vision_config=config.vision_config,
                 norm_eps=getattr(config, "rms_norm_eps", 1e-6),
                 quant_config=self.quant_config,
+                multimodal_config=self.multimodal_config,
                 prefix=maybe_prefix(prefix, "visual"),
-                use_data_parallel=self.use_data_parallel,
-                attn_backend_override=attn_backend_override,
             )
         else:
             self.visual = None

vllm/model_executor/models/ovis2_5.py

@@ -10,8 +10,7 @@ import torch
 import torch.nn as nn
 from transformers import BaseImageProcessor, BatchFeature, PretrainedConfig
 
-from vllm.attention.backends.registry import AttentionBackendEnum
+from vllm.config import MultiModalConfig, VllmConfig
-from vllm.config import VllmConfig
 from vllm.config.multimodal import BaseDummyOptions
 from vllm.model_executor.layers.linear import ReplicatedLinear
 from vllm.model_executor.layers.quantization import QuantizationConfig
@@ -104,18 +103,16 @@ class VisualTokenizer(torch.nn.Module):
         config: PretrainedConfig,
         visual_vocab_size: int,
         quant_config: QuantizationConfig | None = None,
+        multimodal_config: MultiModalConfig | None = None,
         prefix: str = "",
-        use_data_parallel: bool = False,
-        attn_backend_override: AttentionBackendEnum | None = None,
     ):
         super().__init__()
         self.config = config
         self.vit = self._init_backbone(
             config=config,
             quant_config=quant_config,
+            multimodal_config=multimodal_config,
             prefix=f"{prefix}.vit",
-            use_data_parallel=use_data_parallel,
-            attn_backend_override=attn_backend_override,
         )
         # reserved tokens for INDICATOR_IDS
         head_dim = visual_vocab_size - len(INDICATOR_IDS)
@@ -133,18 +130,16 @@ class VisualTokenizer(torch.nn.Module):
         self,
         config: PretrainedConfig,
         quant_config: QuantizationConfig | None = None,
+        multimodal_config: QuantizationConfig | None = None,
         prefix: str = "",
-        use_data_parallel: bool = False,
-        attn_backend_override: AttentionBackendEnum | None = None,
     ):
         model_type = config.model_type
         if model_type == "siglip2_navit":
             return Siglip2NavitModel(
                 config=config,
                 quant_config=quant_config,
+                multimodal_config=multimodal_config,
                 prefix=prefix,
-                use_data_parallel=use_data_parallel,
-                attn_backend_override=attn_backend_override,
             )
         raise ValueError(f"Unsupported visual tokenizer model_type: {model_type}")
 
@@ -468,17 +463,12 @@ class Ovis2_5(nn.Module, SupportsMultiModal, SupportsPP):
             prefix=maybe_prefix(prefix, "llm"),
         )
 
-        attn_backend_override = (
-            multimodal_config.mm_encoder_attn_backend
-            if multimodal_config is not None
-            else None
-        )
         self.visual_tokenizer = VisualTokenizer(
             config=config.vit_config,
             visual_vocab_size=config.visual_vocab_size,
+            multimodal_config=multimodal_config,
             quant_config=quant_config,
             prefix=f"{prefix}.visual_tokenizer",
-            attn_backend_override=attn_backend_override,
         )
 
         self.vte = VisualEmbedding(config.visual_vocab_size, config.hidden_size)

vllm/model_executor/models/paddleocr_vl.py

@@ -22,7 +22,6 @@ from typing import Annotated, Literal
 import numpy as np
 import torch
 import torch.nn as nn
-import torch.nn.functional as F
 from einops import rearrange, repeat
 from transformers import BatchFeature, PretrainedConfig
 from transformers.activations import GELUActivation
@@ -32,13 +31,10 @@ from transformers.modeling_outputs import (
 from transformers.utils import torch_int
 
 from vllm.attention.backends.registry import AttentionBackendEnum
-from vllm.attention.layer import (
+from vllm.attention.layers.mm_encoder_attention import (
-    maybe_get_vit_flash_attn_backend,
+    MMEncoderAttention,
 )
-from vllm.attention.ops.vit_attn_wrappers import (
+from vllm.config import MultiModalConfig, VllmConfig
-    vit_flash_attn_wrapper,
-)
-from vllm.config import VllmConfig
 from vllm.config.multimodal import BaseDummyOptions
 from vllm.distributed import parallel_state
 from vllm.distributed import utils as dist_utils
@@ -578,9 +574,8 @@ class SiglipAttention(nn.Module):
         num_heads: int,
         projection_size: int,
         quant_config: QuantizationConfig | None = None,
+        multimodal_config: MultiModalConfig | None = None,
         prefix: str = "",
-        attn_backend: AttentionBackendEnum = AttentionBackendEnum.TORCH_SDPA,
-        attn_backend_override: AttentionBackendEnum | None = None,
     ) -> None:
         super().__init__()
 
@@ -608,18 +603,12 @@ class SiglipAttention(nn.Module):
             quant_config=quant_config,
             prefix=f"{prefix}.out_proj",
         )
-
+        self.attn = MMEncoderAttention(
-        self.attn_backend = attn_backend
+            num_heads=self.num_attention_heads_per_partition,
-        self.attn_backend, self.flash_attn_varlen_func = (
+            head_size=self.hidden_size_per_attention_head,
-            maybe_get_vit_flash_attn_backend(
+            multimodal_config=multimodal_config,
-                self.attn_backend,
+            prefix=f"{prefix}.attn",
-                attn_backend_override=attn_backend_override,
-            )
         )
-        self.is_flash_attn_backend = self.attn_backend in {
-            AttentionBackendEnum.FLASH_ATTN,
-            AttentionBackendEnum.ROCM_AITER_FA,
-        }
 
     def split_qkv(self, qkv: torch.Tensor) -> tuple[torch.Tensor, ...]:
         seq_len, bs, _ = qkv.shape
@@ -665,44 +654,16 @@ class SiglipAttention(nn.Module):
             qk_rotated = apply_rotary_pos_emb_vision(qk_concat, rotary_pos_emb)
             q, k = torch.chunk(qk_rotated, 2, dim=0)
 
-        if self.is_flash_attn_backend:
+        context_layer = self.attn(
-            if max_seqlen is None:
+            query=q,
-                raise ValueError("Flash attention backend requires max_seqlen.")
+            key=k,
-            context_layer = vit_flash_attn_wrapper(
+            value=v,
-                q,
+            cu_seqlens=cu_seqlens,
-                k,
+            max_seqlen=max_seqlen,
-                v,
+        )
-                cu_seqlens,
+        context_layer = rearrange(context_layer, "b s h d -> b s (h d)")
-                max_seqlen,
-                batch_size,
-                self.attn_backend == AttentionBackendEnum.ROCM_AITER_FA,
-            )
-        elif self.attn_backend == AttentionBackendEnum.TORCH_SDPA:
-            outputs = []
-            for i in range(1, len(cu_seqlens)):
-                start_idx = cu_seqlens[i - 1]
-                end_idx = cu_seqlens[i]
-                q_i = q[:, start_idx:end_idx]
-                k_i = k[:, start_idx:end_idx]
-                v_i = v[:, start_idx:end_idx]
-                q_i, k_i, v_i = (
-                    rearrange(tensor, "b s h d -> b h s d")
-                    for tensor in (q_i, k_i, v_i)
-                )
-                output_i = F.scaled_dot_product_attention(q_i, k_i, v_i, dropout_p=0.0)
-                output_i = rearrange(output_i, "b h s d -> b s h d")
-                outputs.append(output_i)
-            context_layer = torch.cat(outputs, dim=1)
-            context_layer = rearrange(
-                context_layer, "b s h d -> s b (h d)"
-            ).contiguous()
-        else:
-            raise RuntimeError(
-                f"PaddleOCR-VL does not support {self.attn_backend} backend now."
-            )
 
         output, _ = self.out_proj(context_layer)
-        output = rearrange(output, "s b d -> b s d")
         return output
 
 
@@ -774,10 +735,8 @@ class SiglipEncoderLayer(nn.Module):
         self,
         config: PretrainedConfig,
         quant_config: QuantizationConfig | None = None,
+        multimodal_config: MultiModalConfig | None = None,
         prefix: str = "",
-        *,
-        attn_backend: AttentionBackendEnum = AttentionBackendEnum.TORCH_SDPA,
-        attn_backend_override: AttentionBackendEnum | None = None,
     ):
         super().__init__()
         self.embed_dim = config.hidden_size
@@ -787,9 +746,8 @@ class SiglipEncoderLayer(nn.Module):
             num_heads=config.num_attention_heads,
             projection_size=config.hidden_size,
             quant_config=quant_config,
+            multimodal_config=multimodal_config,
             prefix=f"{prefix}.self_attn",
-            attn_backend=attn_backend,
-            attn_backend_override=attn_backend_override,
         )
         self.layer_norm2 = nn.LayerNorm(self.embed_dim, eps=config.layer_norm_eps)
         self.mlp = SiglipMLP(
@@ -832,14 +790,18 @@ class SiglipEncoder(nn.Module):
         self,
         config: PretrainedConfig,
         quant_config: QuantizationConfig | None = None,
+        multimodal_config: MultiModalConfig | None = None,
         prefix: str = "",
-        attn_backend_override: AttentionBackendEnum | None = None,
     ):
         super().__init__()
         self.config = config
         embed_dim = config.hidden_size
         num_heads = config.num_attention_heads
         head_dim = embed_dim // num_heads
+
+        attn_backend_override = (
+            multimodal_config.mm_encoder_attn_backend if multimodal_config else None
+        )
         self.attn_backend = get_vit_attn_backend(
             head_size=head_dim,
             dtype=torch.get_default_dtype(),
@@ -858,9 +820,8 @@ class SiglipEncoder(nn.Module):
                 SiglipEncoderLayer(
                     config,
                     quant_config=quant_config,
+                    multimodal_config=multimodal_config,
                     prefix=f"{prefix}.layers.{layer_idx}",
-                    attn_backend=self.attn_backend,
-                    attn_backend_override=attn_backend_override,
                 )
                 for layer_idx in range(config.num_hidden_layers)
             ]
@@ -941,8 +902,8 @@ class SiglipVisionTransformer(nn.Module):
         self,
         config: PretrainedConfig,
         quant_config: QuantizationConfig | None = None,
+        multimodal_config: MultiModalConfig | None = None,
         prefix: str = "",
-        attn_backend_override: AttentionBackendEnum | None = None,
     ):
         super().__init__()
         self.config = config
@@ -952,8 +913,8 @@ class SiglipVisionTransformer(nn.Module):
         self.encoder = SiglipEncoder(
             config,
             quant_config=quant_config,
+            multimodal_config=multimodal_config,
             prefix=f"{prefix}.encoder",
-            attn_backend_override=attn_backend_override,
         )
         self.post_layernorm = nn.LayerNorm(embed_dim, eps=config.layer_norm_eps)
 
@@ -991,16 +952,16 @@ class SiglipVisionModel(nn.Module):
         self,
         config,
         quant_config: QuantizationConfig | None = None,
+        multimodal_config: MultiModalConfig | None = None,
         prefix: str = "",
-        attn_backend_override: AttentionBackendEnum | None = None,
     ):
         super().__init__()
 
         self.vision_model = SiglipVisionTransformer(
             config,
             quant_config=quant_config,
+            multimodal_config=multimodal_config,
             prefix=f"{prefix}.vision_model",
-            attn_backend_override=attn_backend_override,
         )
         self.quant_config = quant_config
 
@@ -1119,17 +1080,11 @@ class PaddleOCRVLForConditionalGeneration(nn.Module, SupportsMultiModal, Support
         self.config = config
         self.multimodal_config = multimodal_config
 
-        attn_backend_override = (
-            multimodal_config.mm_encoder_attn_backend
-            if multimodal_config is not None
-            else None
-        )
-
         self.visual = SiglipVisionModel(
             config=config.vision_config,
             quant_config=quant_config,
+            multimodal_config=multimodal_config,
             prefix=maybe_prefix(prefix, "visual"),
-            attn_backend_override=attn_backend_override,
         )
         self.mlp_AR = Projector(config, config.vision_config)
 

vllm/model_executor/models/qwen2_5_omni_thinker.py

@@ -845,6 +845,7 @@ class Qwen2_5OmniThinkerForConditionalGeneration(
                 norm_eps=getattr(thinker_config.text_config, "rms_norm_eps", 1e-6),
                 quant_config=quant_config,
                 prefix=maybe_prefix(prefix, "visual"),
+                multimodal_config=multimodal_config,
             )
         else:
             self.visual = None

vllm/model_executor/models/qwen2_5_vl.py

@@ -42,13 +42,9 @@ from transformers.models.qwen2_5_vl.configuration_qwen2_5_vl import (
 )
 
 from vllm.attention.backends.registry import AttentionBackendEnum
-from vllm.attention.layer import maybe_get_vit_flash_attn_backend
+from vllm.attention.layers.mm_encoder_attention import MMEncoderAttention
-from vllm.attention.ops.vit_attn_wrappers import (
-    vit_flash_attn_wrapper,
-    vit_torch_sdpa_wrapper,
-)
 from vllm.compilation.decorators import support_torch_compile
-from vllm.config import VllmConfig
+from vllm.config import MultiModalConfig, VllmConfig
 from vllm.distributed import parallel_state
 from vllm.distributed import utils as dist_utils
 from vllm.forward_context import set_forward_context
@@ -267,10 +263,15 @@ class Qwen2_5_VisionMLP(nn.Module):
         bias: bool = False,
         act_fn: Callable[[torch.Tensor], torch.Tensor] = F.silu,
         quant_config: QuantizationConfig | None = None,
+        multimodal_config: MultiModalConfig | None = None,
         prefix: str = "",
-        use_data_parallel: bool = False,
     ):
         super().__init__()
+        use_data_parallel = (
+            multimodal_config.mm_encoder_tp_mode == "data"
+            if multimodal_config
+            else False
+        )
         self.gate_up_proj = MergedColumnParallelLinear(
             input_size=in_features,
             output_sizes=[hidden_features] * 2,  # [gate_proj, up_proj]
@@ -304,13 +305,16 @@ class Qwen2_5_VisionAttention(nn.Module):
         num_heads: int,
         projection_size: int,
         quant_config: QuantizationConfig | None = None,
+        multimodal_config: MultiModalConfig | None = None,
         prefix: str = "",
-        use_data_parallel: bool = False,
-        attn_backend: AttentionBackendEnum = AttentionBackendEnum.TORCH_SDPA,
-        attn_backend_override: AttentionBackendEnum | None = None,
     ) -> None:
         super().__init__()
         # Per attention head and per partition values.
+        use_data_parallel = (
+            multimodal_config.mm_encoder_tp_mode == "data"
+            if multimodal_config
+            else False
+        )
         self.tp_size = (
             1
             if use_data_parallel
@@ -342,18 +346,12 @@ class Qwen2_5_VisionAttention(nn.Module):
             prefix=f"{prefix}.proj",
             disable_tp=use_data_parallel,
         )
-        self.attn_backend = attn_backend
-        self.attn_backend, self.flash_attn_varlen_func = (
-            maybe_get_vit_flash_attn_backend(
-                self.attn_backend,
-                attn_backend_override=attn_backend_override,
-            )
-        )
 
-        self.is_flash_attn_backend = self.attn_backend in {
+        self.attn = MMEncoderAttention(
-            AttentionBackendEnum.FLASH_ATTN,
+            num_heads=self.num_attention_heads_per_partition,
-            AttentionBackendEnum.ROCM_AITER_FA,
+            head_size=self.hidden_size_per_attention_head,
-        }
+            multimodal_config=multimodal_config,
+        )
 
     def forward(
         self,
@@ -394,32 +392,17 @@ class Qwen2_5_VisionAttention(nn.Module):
         else:
             q, k, v = qkv.unbind(dim=2)
 
-        if self.is_flash_attn_backend:
+        context_layer = self.attn(
-            context_layer = vit_flash_attn_wrapper(
+            query=q,
-                q,
+            key=k,
-                k,
+            value=v,
-                v,
+            cu_seqlens=cu_seqlens,
-                cu_seqlens,
+            max_seqlen=max_seqlen,
-                max_seqlen,
+        )
-                batch_size,
-                self.attn_backend == AttentionBackendEnum.ROCM_AITER_FA,
-            )
-        elif self.attn_backend == AttentionBackendEnum.TORCH_SDPA:
-            # Execute attention entry by entry for speed & less VRAM.
-            from vllm.platforms import current_platform
 
-            # Never remove the next contiguous logic
+        context_layer = einops.rearrange(
-            # Without it, hallucinations occur with the backend
+            context_layer, "b s h d -> s b (h d)", b=batch_size
-            if current_platform.is_rocm():
+        ).contiguous()
-                q = q.contiguous()
-                k = k.contiguous()
-                v = v.contiguous()
-            context_layer = vit_torch_sdpa_wrapper(
-                q,
-                k,
-                v,
-                cu_seqlens,
-            )
 
         output, _ = self.proj(context_layer)
         return output
@@ -443,10 +426,8 @@ class Qwen2_5_VisionBlock(nn.Module):
         act_fn: Callable[[torch.Tensor], torch.Tensor] = F.silu,
         norm_layer: Callable[[int], nn.Module] | None = None,
         quant_config: QuantizationConfig | None = None,
+        multimodal_config: MultiModalConfig | None = None,
         prefix: str = "",
-        use_data_parallel: bool = False,
-        attn_backend: AttentionBackendEnum = AttentionBackendEnum.TORCH_SDPA,
-        attn_backend_override: AttentionBackendEnum | None = None,
     ) -> None:
         super().__init__()
         if norm_layer is None:
@@ -458,10 +439,8 @@ class Qwen2_5_VisionBlock(nn.Module):
             num_heads=num_heads,
             projection_size=dim,
             quant_config=quant_config,
+            multimodal_config=multimodal_config,
             prefix=f"{prefix}.attn",
-            use_data_parallel=use_data_parallel,
-            attn_backend=attn_backend,
-            attn_backend_override=attn_backend_override,
         )
         self.mlp = Qwen2_5_VisionMLP(
             dim,
@@ -469,8 +448,8 @@ class Qwen2_5_VisionBlock(nn.Module):
             act_fn=act_fn,
             bias=True,
             quant_config=quant_config,
+            multimodal_config=multimodal_config,
             prefix=f"{prefix}.mlp",
-            use_data_parallel=use_data_parallel,
         )
 
     def forward(
@@ -542,10 +521,15 @@ class Qwen2_5_VisionPatchMerger(nn.Module):
         norm_layer: Callable[[int], nn.Module] | None = None,
         spatial_merge_size: int = 2,
         quant_config: QuantizationConfig | None = None,
+        multimodal_config: MultiModalConfig | None = None,
         prefix: str = "",
-        use_data_parallel: bool = False,
     ) -> None:
         super().__init__()
+        use_data_parallel = (
+            multimodal_config.mm_encoder_tp_mode == "data"
+            if multimodal_config
+            else False
+        )
         self.hidden_size = context_dim * (spatial_merge_size**2)
         if norm_layer is None:
             norm_layer = partial(nn.LayerNorm, eps=1e-6)
@@ -586,9 +570,8 @@ class Qwen2_5_VisionTransformer(nn.Module):
         vision_config: Qwen2_5_VLVisionConfig,
         norm_eps: float = 1e-6,
         quant_config: QuantizationConfig | None = None,
+        multimodal_config: MultiModalConfig | None = None,
         prefix: str = "",
-        use_data_parallel: bool = False,
-        attn_backend_override: AttentionBackendEnum | None = None,
     ) -> None:
         super().__init__()
 
@@ -598,7 +581,6 @@ class Qwen2_5_VisionTransformer(nn.Module):
         depth = vision_config.depth
         self.hidden_size = vision_config.hidden_size
         self.num_heads = vision_config.num_heads
-        self.use_data_parallel = use_data_parallel
         self.out_hidden_size = vision_config.out_hidden_size
 
         # args for get_window_index_thw
@@ -629,19 +611,17 @@ class Qwen2_5_VisionTransformer(nn.Module):
             rope_parameters={"partial_rotary_factor": 0.5},
         )
 
+        attn_backend_override = (
+            multimodal_config.mm_encoder_attn_backend
+            if multimodal_config is not None
+            else None
+        )
         self.attn_backend = get_vit_attn_backend(
             head_size=head_dim,
             dtype=torch.get_default_dtype(),
             attn_backend_override=attn_backend_override,
         )
 
-        self.attn_backend, self.flash_attn_varlen_func = (
-            maybe_get_vit_flash_attn_backend(
-                self.attn_backend,
-                attn_backend_override=attn_backend_override,
-            )
-        )
-
         if self.attn_backend not in {
             AttentionBackendEnum.FLASH_ATTN,
             AttentionBackendEnum.TORCH_SDPA,
@@ -661,10 +641,8 @@ class Qwen2_5_VisionTransformer(nn.Module):
                         act_fn=get_act_and_mul_fn(vision_config.hidden_act),
                         norm_layer=norm_layer,
                         quant_config=quant_config,
+                        multimodal_config=multimodal_config,
                         prefix=f"{prefix}.blocks.{layer_idx}",
-                        use_data_parallel=use_data_parallel,
-                        attn_backend=self.attn_backend,
-                        attn_backend_override=attn_backend_override,
                     )
                     for layer_idx in range(depth)
                 ]
@@ -677,8 +655,8 @@ class Qwen2_5_VisionTransformer(nn.Module):
                 norm_layer=norm_layer,
                 spatial_merge_size=self.spatial_merge_size,
                 quant_config=quant_config,
+                multimodal_config=multimodal_config,
                 prefix=f"{prefix}.merger",
-                use_data_parallel=use_data_parallel,
             )
 
     @property
@@ -1200,18 +1178,12 @@ class Qwen2_5_VLForConditionalGeneration(
         if multimodal_config.get_limit_per_prompt(
             "image"
         ) or multimodal_config.get_limit_per_prompt("video"):
-            attn_backend_override = (
-                multimodal_config.mm_encoder_attn_backend
-                if multimodal_config is not None
-                else None
-            )
             self.visual = Qwen2_5_VisionTransformer(
                 vision_config=config.vision_config,
                 norm_eps=getattr(config, "rms_norm_eps", 1e-6),
                 quant_config=self.quant_config,
                 prefix=maybe_prefix(prefix, "visual"),
-                use_data_parallel=self.use_data_parallel,
+                multimodal_config=multimodal_config,
-                attn_backend_override=attn_backend_override,
             )
         else:
             self.visual = None

vllm/model_executor/models/qwen2_vl.py

@@ -33,7 +33,6 @@ from typing import Annotated, Any, Literal, TypeAlias
 import numpy as np
 import torch
 import torch.nn as nn
-import torch.nn.functional as F
 from einops import rearrange
 from transformers import BatchFeature
 from transformers.models.qwen2_vl import Qwen2VLImageProcessor, Qwen2VLProcessor
@@ -45,10 +44,8 @@ from transformers.models.qwen2_vl.image_processing_qwen2_vl import smart_resize
 from transformers.models.qwen2_vl.video_processing_qwen2_vl import Qwen2VLVideoProcessor
 
 from vllm.attention.backends.registry import AttentionBackendEnum
-from vllm.attention.layer import (
+from vllm.attention.layers.mm_encoder_attention import MMEncoderAttention
-    maybe_get_vit_flash_attn_backend,
+from vllm.config import MultiModalConfig, VllmConfig
-)
-from vllm.config import VllmConfig
 from vllm.config.multimodal import BaseDummyOptions
 from vllm.distributed import parallel_state, tensor_model_parallel_all_gather
 from vllm.distributed import utils as dist_utils
@@ -251,10 +248,15 @@ class Qwen2VisionMLP(nn.Module):
         hidden_features: int,
         act_layer: type[nn.Module] = QuickGELU,
         quant_config: QuantizationConfig | None = None,
+        multimodal_config: MultiModalConfig | None = None,
         prefix: str = "",
-        use_data_parallel: bool = False,
     ):
         super().__init__()
+        use_data_parallel = (
+            multimodal_config.mm_encoder_tp_mode == "data"
+            if multimodal_config
+            else False
+        )
         self.fc1 = ColumnParallelLinear(
             in_features,
             hidden_features,
@@ -295,12 +297,16 @@ class Qwen2VisionAttention(nn.Module):
         num_heads: int,
         projection_size: int,
         quant_config: QuantizationConfig | None = None,
+        multimodal_config: MultiModalConfig | None = None,
         prefix: str = "",
-        use_data_parallel: bool = False,
-        attn_backend_override: AttentionBackendEnum | None = None,
     ) -> None:
         super().__init__()
         # Per attention head and per partition values.
+        use_data_parallel = (
+            multimodal_config.mm_encoder_tp_mode == "data"
+            if multimodal_config
+            else False
+        )
         self.tp_size = (
             1
             if use_data_parallel
@@ -329,34 +335,12 @@ class Qwen2VisionAttention(nn.Module):
             disable_tp=use_data_parallel,
         )
 
-        # Detect attention implementation.
+        self.attn = MMEncoderAttention(
-        self.attn_backend = get_vit_attn_backend(
+            num_heads=self.num_attention_heads_per_partition,
             head_size=self.hidden_size_per_attention_head,
-            dtype=torch.get_default_dtype(),
+            multimodal_config=multimodal_config,
-            attn_backend_override=attn_backend_override,
         )
 
-        self.attn_backend, self.flash_attn_varlen_func = (
-            maybe_get_vit_flash_attn_backend(
-                self.attn_backend,
-                attn_backend_override=attn_backend_override,
-            )
-        )
-
-        if self.attn_backend not in {
-            AttentionBackendEnum.FLASH_ATTN,
-            AttentionBackendEnum.TORCH_SDPA,
-            AttentionBackendEnum.ROCM_AITER_FA,
-        }:
-            raise RuntimeError(
-                f"Qwen2-VL does not support {self.attn_backend} backend now."
-            )
-
-        self.is_flash_attn_backend = self.attn_backend in {
-            AttentionBackendEnum.FLASH_ATTN,
-            AttentionBackendEnum.ROCM_AITER_FA,
-        }
-
     def split_qkv(self, qkv: torch.Tensor) -> tuple[torch.Tensor, ...]:
         # [s, b, 3 * head * head_dim]
         seq_len, bs, _ = qkv.shape
@@ -398,7 +382,6 @@ class Qwen2VisionAttention(nn.Module):
 
         # [s, b, 3 * head * head_dim] -> 3 * [s, b, head, head_dim]
         q, k, v = self.split_qkv(x)
-        batch_size = q.shape[1]
 
         q, k, v = (rearrange(x, "s b ... -> b s ...") for x in (q, k, v))
 
@@ -409,49 +392,15 @@ class Qwen2VisionAttention(nn.Module):
         )
         q, k = torch.chunk(qk_rotated, 2, dim=0)
 
-        if self.is_flash_attn_backend:
+        context_layer = self.attn(
-            q, k, v = (rearrange(x, "b s ... -> (b s) ...") for x in [q, k, v])
+            query=q,
+            key=k,
+            value=v,
+            cu_seqlens=cu_seqlens,
+            max_seqlen=max_seqlen,
+        )
 
-            output = self.flash_attn_varlen_func(
+        context_layer = rearrange(context_layer, "b s h d -> s b (h d)").contiguous()
-                q,
-                k,
-                v,
-                cu_seqlens_q=cu_seqlens,
-                cu_seqlens_k=cu_seqlens,
-                max_seqlen_q=max_seqlen,
-                max_seqlen_k=max_seqlen,
-                dropout_p=0.0,
-                causal=False,
-            )
-
-            context_layer = rearrange(
-                output, "(b s) h d -> s b (h d)", b=batch_size
-            ).contiguous()
-        elif self.attn_backend == AttentionBackendEnum.TORCH_SDPA:
-            # Execute attention entry by entry for speed & less VRAM.
-            from vllm.platforms import current_platform
-
-            if current_platform.is_rocm():
-                q = q.contiguous()
-                k = k.contiguous()
-                v = v.contiguous()
-            outputs = []
-
-            lens = (cu_seqlens[1:] - cu_seqlens[:-1]).tolist()
-            q_chunks = torch.split(q, lens, dim=1)
-            k_chunks = torch.split(k, lens, dim=1)
-            v_chunks = torch.split(v, lens, dim=1)
-            for q_i, k_i, v_i in zip(q_chunks, k_chunks, v_chunks):
-                q_i, k_i, v_i = (
-                    rearrange(x, "b s h d -> b h s d") for x in [q_i, k_i, v_i]
-                )
-                output_i = F.scaled_dot_product_attention(q_i, k_i, v_i, dropout_p=0.0)
-                output_i = rearrange(output_i, "b h s d -> b s h d ")
-                outputs.append(output_i)
-            context_layer = torch.cat(outputs, dim=1)
-            context_layer = rearrange(
-                context_layer, "b s h d -> s b (h d)"
-            ).contiguous()
 
         output, _ = self.proj(context_layer)
         return output
@@ -466,9 +415,8 @@ class Qwen2VisionBlock(nn.Module):
         act_layer: type[nn.Module] = QuickGELU,
         norm_layer: Callable[[int], nn.Module] | None = None,
         quant_config: QuantizationConfig | None = None,
+        multimodal_config: MultiModalConfig | None = None,
         prefix: str = "",
-        use_data_parallel: bool = False,
-        attn_backend_override: AttentionBackendEnum | None = None,
     ) -> None:
         super().__init__()
         if norm_layer is None:
@@ -482,17 +430,16 @@ class Qwen2VisionBlock(nn.Module):
             num_heads=num_heads,
             projection_size=dim,
             quant_config=quant_config,
+            multimodal_config=multimodal_config,
             prefix=f"{prefix}.attn",
-            use_data_parallel=use_data_parallel,
-            attn_backend_override=attn_backend_override,
         )
         self.mlp = Qwen2VisionMLP(
             dim,
             mlp_hidden_dim,
             act_layer=act_layer,
             quant_config=quant_config,
+            multimodal_config=multimodal_config,
             prefix=f"{prefix}.mlp",
-            use_data_parallel=use_data_parallel,
         )
 
     def forward(
@@ -552,10 +499,15 @@ class Qwen2VisionPatchMerger(nn.Module):
         norm_layer: Callable[[int], nn.Module] | None = None,
         spatial_merge_size: int = 2,
         quant_config: QuantizationConfig | None = None,
+        multimodal_config: MultiModalConfig | None = None,
         prefix: str = "",
-        use_data_parallel: bool = False,
     ) -> None:
         super().__init__()
+        use_data_parallel = (
+            multimodal_config.mm_encoder_tp_mode == "data"
+            if multimodal_config
+            else False
+        )
         self.hidden_size = context_dim * (spatial_merge_size**2)
         if norm_layer is None:
             norm_layer = partial(nn.LayerNorm, eps=1e-6)
@@ -599,9 +551,8 @@ class Qwen2VisionTransformer(nn.Module):
         vision_config: Qwen2VLVisionConfig,
         norm_eps: float = 1e-6,
         quant_config: QuantizationConfig | None = None,
+        multimodal_config: MultiModalConfig | None = None,
         prefix: str = "",
-        use_data_parallel: bool = False,
-        attn_backend_override: AttentionBackendEnum | None = None,
     ) -> None:
         super().__init__()
 
@@ -615,7 +566,11 @@ class Qwen2VisionTransformer(nn.Module):
         num_heads = vision_config.num_heads
         mlp_ratio = vision_config.mlp_ratio
 
-        self.use_data_parallel = use_data_parallel
+        self.use_data_parallel = (
+            multimodal_config.mm_encoder_tp_mode == "data"
+            if multimodal_config
+            else False
+        )
         self.out_hidden_size = vision_config.hidden_size
 
         self.spatial_merge_size = spatial_merge_size
@@ -647,8 +602,7 @@ class Qwen2VisionTransformer(nn.Module):
                     norm_layer=norm_layer,
                     quant_config=quant_config,
                     prefix=f"{prefix}.blocks.{layer_idx}",
-                    use_data_parallel=use_data_parallel,
+                    multimodal_config=multimodal_config,
-                    attn_backend_override=attn_backend_override,
                 )
                 for layer_idx in range(depth)
             ]
@@ -659,7 +613,10 @@ class Qwen2VisionTransformer(nn.Module):
             norm_layer=norm_layer,
             quant_config=quant_config,
             prefix=f"{prefix}.merger",
-            use_data_parallel=use_data_parallel,
+            multimodal_config=multimodal_config,
+        )
+        attn_backend_override = (
+            multimodal_config.mm_encoder_attn_backend if multimodal_config else None
         )
         self.attn_backend = get_vit_attn_backend(
             head_size=head_dim,
@@ -720,7 +677,7 @@ class Qwen2VisionTransformer(nn.Module):
             AttentionBackendEnum.FLASH_ATTN,
             AttentionBackendEnum.ROCM_AITER_FA,
         }:
-            max_seqlen = (cu_seqlens[1:] - cu_seqlens[:-1]).max().item()
+            max_seqlen = (cu_seqlens[1:] - cu_seqlens[:-1]).max()
         return max_seqlen
 
     def forward(
@@ -1324,18 +1281,12 @@ class Qwen2VLForConditionalGeneration(
         if multimodal_config.get_limit_per_prompt(
             "image"
         ) or multimodal_config.get_limit_per_prompt("video"):
-            attn_backend_override = (
-                multimodal_config.mm_encoder_attn_backend
-                if multimodal_config is not None
-                else None
-            )
             self.visual = Qwen2VisionTransformer(
                 config.vision_config,
                 norm_eps=getattr(config, "rms_norm_eps", 1e-6),
                 quant_config=quant_config,
+                multimodal_config=multimodal_config,
                 prefix=maybe_prefix(prefix, "visual"),
-                use_data_parallel=self.use_data_parallel,
-                attn_backend_override=attn_backend_override,
             )
         else:
             self.visual = None

vllm/model_executor/models/qwen3_omni_moe_thinker.py

@@ -48,7 +48,7 @@ from transformers.models.whisper import WhisperFeatureExtractor
 
 from vllm.attention.backends.registry import AttentionBackendEnum
 from vllm.compilation.decorators import support_torch_compile
-from vllm.config import VllmConfig
+from vllm.config import MultiModalConfig, VllmConfig
 from vllm.distributed import get_pp_group
 from vllm.logger import init_logger
 from vllm.model_executor.layers.activation import _ACTIVATION_REGISTRY
@@ -192,6 +192,7 @@ class Qwen3_VisionBlock(nn.Module):
         mlp_hidden_dim: int,
         act_fn: Callable[[torch.Tensor], torch.Tensor] = F.silu,
         norm_layer: Callable[[int], nn.Module] | None = None,
+        multimodal_config: MultiModalConfig | None = None,
         quant_config: QuantizationConfig | None = None,
         prefix: str = "",
     ) -> None:
@@ -205,6 +206,7 @@ class Qwen3_VisionBlock(nn.Module):
             num_heads=num_heads,
             projection_size=dim,
             quant_config=quant_config,
+            multimodal_config=multimodal_config,
             prefix=f"{prefix}.attn",
         )
         self.mlp = Qwen3_VisionMLP(
@@ -299,8 +301,8 @@ class Qwen3Omni_VisionTransformer(nn.Module):
         vision_config,
         norm_eps: float = 1e-6,
         quant_config: QuantizationConfig | None = None,
+        multimodal_config: MultiModalConfig | None = None,
         prefix: str = "",
-        attn_backend_override: AttentionBackendEnum | None = None,
     ) -> None:
         super().__init__()
         self.hidden_size = vision_config.hidden_size
@@ -347,6 +349,7 @@ class Qwen3Omni_VisionTransformer(nn.Module):
                     act_fn=_ACTIVATION_REGISTRY[vision_config.hidden_act],
                     norm_layer=norm_layer,
                     quant_config=quant_config,
+                    multimodal_config=multimodal_config,
                     prefix=f"{prefix}.blocks.{layer_idx}",
                 )
                 for layer_idx in range(vision_config.depth)
@@ -376,6 +379,12 @@ class Qwen3Omni_VisionTransformer(nn.Module):
                 ]
             )
 
+        attn_backend_override = (
+            multimodal_config.mm_encoder_attn_backend
+            if multimodal_config is not None
+            else None
+        )
+
         self.attn_backend = get_vit_attn_backend(
             head_size=head_dim,
             dtype=torch.get_default_dtype(),
@@ -1188,17 +1197,12 @@ class Qwen3OmniMoeThinkerForConditionalGeneration(
 
         self.audio_tower = Qwen3OmniMoeAudioEncoder(thinker_config.audio_config)
 
-        attn_backend_override = (
-            multimodal_config.mm_encoder_attn_backend
-            if multimodal_config is not None
-            else None
-        )
         self.visual = Qwen3Omni_VisionTransformer(
             vision_config=thinker_config.vision_config,
             norm_eps=getattr(thinker_config.text_config, "rms_norm_eps", 1e-6),
             quant_config=quant_config,
             prefix=maybe_prefix(prefix, "visual"),
-            attn_backend_override=attn_backend_override,
+            multimodal_config=multimodal_config,
         )
         self.quant_config = quant_config
 

vllm/model_executor/models/qwen3_vl.py

@@ -50,7 +50,7 @@ from transformers.video_utils import VideoMetadata
 
 from vllm.attention.backends.registry import AttentionBackendEnum
 from vllm.compilation.decorators import support_torch_compile
-from vllm.config import VllmConfig
+from vllm.config import MultiModalConfig, VllmConfig
 from vllm.config.multimodal import BaseDummyOptions, VideoDummyOptions
 from vllm.distributed import get_pp_group
 from vllm.logger import init_logger
@@ -169,10 +169,15 @@ class Qwen3_VisionMLP(nn.Module):
         bias: bool = False,
         act_fn: Callable[[torch.Tensor], torch.Tensor] = F.silu,
         quant_config: QuantizationConfig | None = None,
+        multimodal_config: MultiModalConfig | None = None,
         prefix: str = "",
-        use_data_parallel: bool = False,
     ):
         super().__init__()
+        use_data_parallel = (
+            multimodal_config.mm_encoder_tp_mode == "data"
+            if multimodal_config
+            else False
+        )
         self.linear_fc1 = ColumnParallelLinear(
             in_features,
             hidden_features,
@@ -206,10 +211,9 @@ class Qwen3_VisionBlock(nn.Module):
         mlp_hidden_dim: int,
         act_fn: Callable[[torch.Tensor], torch.Tensor] = F.silu,
         norm_layer: Callable[[int], nn.Module] | None = None,
+        multimodal_config: MultiModalConfig | None = None,
         quant_config: QuantizationConfig | None = None,
         prefix: str = "",
-        use_data_parallel: bool = False,
-        attn_backend: AttentionBackendEnum = AttentionBackendEnum.TORCH_SDPA,
     ) -> None:
         super().__init__()
         if norm_layer is None:
@@ -221,9 +225,8 @@ class Qwen3_VisionBlock(nn.Module):
             num_heads=num_heads,
             projection_size=dim,
             quant_config=quant_config,
+            multimodal_config=multimodal_config,
             prefix=f"{prefix}.attn",
-            use_data_parallel=use_data_parallel,
-            attn_backend=attn_backend,
         )
         self.mlp = Qwen3_VisionMLP(
             dim,
@@ -231,8 +234,8 @@ class Qwen3_VisionBlock(nn.Module):
             act_fn=act_fn,
             bias=True,
             quant_config=quant_config,
+            multimodal_config=multimodal_config,
             prefix=f"{prefix}.mlp",
-            use_data_parallel=use_data_parallel,
         )
 
     def forward(
@@ -264,10 +267,15 @@ class Qwen3_VisionPatchMerger(nn.Module):
         spatial_merge_size: int = 2,
         use_postshuffle_norm: bool = False,
         quant_config: QuantizationConfig | None = None,
+        multimodal_config: MultiModalConfig | None = None,
         prefix: str = "",
-        use_data_parallel: bool = False,
     ) -> None:
         super().__init__()
+        use_data_parallel = (
+            multimodal_config.mm_encoder_tp_mode == "data"
+            if multimodal_config
+            else False
+        )
         self.hidden_size = context_dim * (spatial_merge_size**2)
 
         self.use_postshuffle_norm = use_postshuffle_norm
@@ -313,9 +321,8 @@ class Qwen3_VisionTransformer(nn.Module):
         vision_config: Qwen3VLVisionConfig,
         norm_eps: float = 1e-6,
         quant_config: QuantizationConfig | None = None,
+        multimodal_config: MultiModalConfig | None = None,
         prefix: str = "",
-        use_data_parallel: bool = False,
-        attn_backend_override: AttentionBackendEnum | None = None,
     ) -> None:
         super().__init__()
         self.hidden_size = vision_config.hidden_size
@@ -326,7 +333,6 @@ class Qwen3_VisionTransformer(nn.Module):
         self.spatial_merge_unit = self.spatial_merge_size**2
         self.temporal_patch_size = vision_config.temporal_patch_size
         self.deepstack_visual_indexes = vision_config.deepstack_visual_indexes
-        self.use_data_parallel = use_data_parallel
         self.num_grid_per_side = int(self.num_position_embeddings**0.5)
 
         # NOTE: This is used for creating empty tensor for all_gather for
@@ -359,8 +365,8 @@ class Qwen3_VisionTransformer(nn.Module):
             norm_layer=norm_layer,
             spatial_merge_size=self.spatial_merge_size,
             quant_config=quant_config,
+            multimodal_config=multimodal_config,
             prefix=f"{prefix}.merger",
-            use_data_parallel=use_data_parallel,
         )
 
         self.deepstack_merger_list = nn.ModuleList(
@@ -372,13 +378,16 @@ class Qwen3_VisionTransformer(nn.Module):
                     use_postshuffle_norm=True,
                     norm_layer=norm_layer,
                     quant_config=quant_config,
+                    multimodal_config=multimodal_config,
                     prefix=f"{prefix}.deepstack_merger_list.{layer_idx}",
-                    use_data_parallel=use_data_parallel,
                 )
                 for layer_idx in range(len(self.deepstack_visual_indexes))
             ]
         )
 
+        attn_backend_override = (
+            multimodal_config.mm_encoder_attn_backend if multimodal_config else None
+        )
         self.attn_backend = get_vit_attn_backend(
             head_size=head_dim,
             dtype=torch.get_default_dtype(),
@@ -402,9 +411,8 @@ class Qwen3_VisionTransformer(nn.Module):
                     act_fn=_ACTIVATION_REGISTRY[vision_config.hidden_act],
                     norm_layer=norm_layer,
                     quant_config=quant_config,
+                    multimodal_config=multimodal_config,
                     prefix=f"{prefix}.blocks.{layer_idx}",
-                    use_data_parallel=use_data_parallel,
-                    attn_backend=self.attn_backend,
                 )
                 for layer_idx in range(vision_config.depth)
             ]
@@ -1277,18 +1285,12 @@ class Qwen3VLForConditionalGeneration(
         ) and not multimodal_config.get_limit_per_prompt("video"):
             self.visual = None
         else:
-            attn_backend_override = (
-                multimodal_config.mm_encoder_attn_backend
-                if multimodal_config is not None
-                else None
-            )
             self.visual = Qwen3_VisionTransformer(
                 config.vision_config,
                 norm_eps=getattr(config, "rms_norm_eps", 1e-6),
                 quant_config=quant_config,
+                multimodal_config=multimodal_config,
                 prefix=maybe_prefix(prefix, "visual"),
-                use_data_parallel=self.use_data_parallel,
-                attn_backend_override=attn_backend_override,
             )
 
         self.language_model = Qwen3LLMForCausalLM(

vllm/model_executor/models/qwen3_vl_moe.py

@@ -418,7 +418,6 @@ class Qwen3VLMoeForConditionalGeneration(
 
         self.config = config
         self.multimodal_config = multimodal_config
-        self.use_data_parallel = multimodal_config.mm_encoder_tp_mode == "data"
 
         if not multimodal_config.get_limit_per_prompt(
             "image"
@@ -429,8 +428,8 @@ class Qwen3VLMoeForConditionalGeneration(
                 config.vision_config,
                 norm_eps=getattr(config, "rms_norm_eps", 1e-6),
                 quant_config=quant_config,
+                multimodal_config=multimodal_config,
                 prefix=maybe_prefix(prefix, "visual"),
-                use_data_parallel=self.use_data_parallel,
             )
 
         self.language_model = Qwen3MoeLLMForCausalLM(

vllm/model_executor/models/siglip2navit.py

@@ -13,7 +13,8 @@ from transformers import Siglip2VisionConfig
 from transformers.configuration_utils import PretrainedConfig
 
 from vllm.attention.backends.registry import AttentionBackendEnum
-from vllm.attention.layer import maybe_get_vit_flash_attn_backend
+from vllm.attention.layers.mm_encoder_attention import MMEncoderAttention
+from vllm.config import MultiModalConfig
 from vllm.distributed import divide, get_tensor_model_parallel_world_size
 from vllm.model_executor.layers.activation import get_act_fn
 from vllm.model_executor.layers.conv import Conv2dLayer
@@ -28,8 +29,6 @@ from vllm.model_executor.layers.quantization import QuantizationConfig
 from vllm.model_executor.model_loader.weight_utils import default_weight_loader
 from vllm.platforms import current_platform
 
-from .vision import get_vit_attn_backend
-
 
 class VisionRotaryEmbedding(nn.Module):
     def __init__(self, dim: int, theta: float = 10000.0) -> None:
@@ -190,7 +189,7 @@ def apply_rotary_pos_emb(
 ) -> tuple[torch.Tensor, torch.Tensor]:
     cos = cos.chunk(2, dim=-1)[0].contiguous()
     sin = sin.chunk(2, dim=-1)[0].contiguous()
-    if is_flash_attn_backend and not current_platform.is_xpu():
+    if is_flash_attn_backend and current_platform.is_cuda():
         from vllm.vllm_flash_attn.layers.rotary import apply_rotary_emb
 
         apply_rotary_emb_func = apply_rotary_emb
@@ -208,6 +207,7 @@ class Siglip2Attention(nn.Module):
         self,
         config: Siglip2VisionConfig,
         quant_config: QuantizationConfig | None = None,
+        multimodal_config: MultiModalConfig | None = None,
         prefix: str = "",
         use_data_parallel: bool = False,
         attn_backend_override: AttentionBackendEnum | None = None,
@@ -227,20 +227,25 @@ class Siglip2Attention(nn.Module):
         self.dropout = config.attention_dropout
         self.is_causal = False
 
-        # TODO(Isotr0py): Enable data parallel after we support
+        use_data_parallel = (
-        # disabling TP on parallel linear layer
+            multimodal_config.mm_encoder_tp_mode == "data"
+            if multimodal_config
+            else False
+        )
         self.qkv_proj = QKVParallelLinear(
             hidden_size=self.embed_dim,
             head_size=self.head_dim,
             total_num_heads=self.num_heads,
             quant_config=quant_config,
             prefix=f"{prefix}.qkv_proj",
+            disable_tp=use_data_parallel,
         )
         self.out_proj = RowParallelLinear(
             input_size=self.embed_dim,
             output_size=self.embed_dim,
             quant_config=quant_config,
             prefix=f"{prefix}.out_proj",
+            disable_tp=use_data_parallel,
         )
 
         self.tp_size = (
@@ -249,31 +254,13 @@ class Siglip2Attention(nn.Module):
         self.num_heads_per_partition = divide(self.num_heads, self.tp_size)
         self.use_rope = config.use_rope
 
-        # Detect attention implementation.
+        self.attn = MMEncoderAttention(
-        self.attn_backend = get_vit_attn_backend(
+            num_heads=self.num_heads_per_partition,
             head_size=self.head_dim,
-            dtype=torch.get_default_dtype(),
+            prefix=f"{prefix}.attn",
-            attn_backend_override=attn_backend_override,
+            multimodal_config=multimodal_config,
         )
 
-        self.attn_backend, self.flash_attn_varlen_func = (
-            maybe_get_vit_flash_attn_backend(
-                self.attn_backend,
-                attn_backend_override=attn_backend_override,
-            )
-        )
-
-        if self.attn_backend not in {
-            AttentionBackendEnum.FLASH_ATTN,
-            AttentionBackendEnum.TORCH_SDPA,
-            AttentionBackendEnum.ROCM_AITER_FA,
-        }:
-            self.attn_backend = AttentionBackendEnum.TORCH_SDPA
-        self.is_flash_attn_backend = self.attn_backend in {
-            AttentionBackendEnum.FLASH_ATTN,
-            AttentionBackendEnum.ROCM_AITER_FA,
-        }
-
     def forward(
         self,
         hidden_states: torch.Tensor,
@@ -298,46 +285,23 @@ class Siglip2Attention(nn.Module):
                 keys.unsqueeze(0),
                 cos,
                 sin,
-                self.is_flash_attn_backend,
+                self.attn.is_flash_attn_backend,
             )
             queries = queries.squeeze(0)
             keys = keys.squeeze(0)
 
-        max_seqlen = (cu_seqlens[1:] - cu_seqlens[:-1]).max().item()
+        max_seqlen = (cu_seqlens[1:] - cu_seqlens[:-1]).max()
-        if self.is_flash_attn_backend:
+        attn_output = self.attn(
-            attn_output = self.flash_attn_varlen_func(
+            query=queries.unsqueeze(0),
-                queries,
+            key=keys.unsqueeze(0),
-                keys,
+            value=values.unsqueeze(0),
-                values,
+            cu_seqlens=cu_seqlens,
-                cu_seqlens_q=cu_seqlens,
+            max_seqlen=max_seqlen,
-                cu_seqlens_k=cu_seqlens,
+        )
-                max_seqlen_q=max_seqlen,
+        attn_output = attn_output.reshape(
-                max_seqlen_k=max_seqlen,
+            seq_length, self.num_heads_per_partition * self.head_dim
-            ).reshape(seq_length, -1)
+        )
-        elif self.attn_backend == AttentionBackendEnum.TORCH_SDPA:
-            # Execute attention entry by entry for speed & less VRAM.
-            batch_size = cu_seqlens.shape[0] - 1
-            outputs = []
-            cu = cu_seqlens.tolist()
-            for i in range(batch_size):
-                start_idx = cu[i]
-                end_idx = cu[i + 1]
 
-                # Each sequence is processed independently.
-                q_i = queries[start_idx:end_idx].unsqueeze(0)
-                k_i = keys[start_idx:end_idx].unsqueeze(0)
-                v_i = values[start_idx:end_idx].unsqueeze(0)
-
-                # (1, seq_len, num_heads, head_dim) ->
-                # (1, num_heads, seq_len, head_dim)
-                q_i, k_i, v_i = [x.transpose(1, 2) for x in (q_i, k_i, v_i)]
-
-                output_i = F.scaled_dot_product_attention(q_i, k_i, v_i, dropout_p=0.0)
-                # (1, num_heads, seq_len, head_dim) -> (seq_len, embed_dim)
-                output_i = output_i.transpose(1, 2).reshape(end_idx - start_idx, -1)
-                outputs.append(output_i)
-
-            attn_output = torch.cat(outputs, dim=0)
         attn_output, _ = self.out_proj(attn_output)
         return attn_output
 
@@ -347,25 +311,30 @@ class Siglip2MLP(nn.Module):
         self,
         config: Siglip2VisionConfig,
         quant_config: QuantizationConfig | None = None,
+        multimodal_config: MultiModalConfig | None = None,
         prefix: str = "",
-        use_data_parallel: bool = False,
     ):
         super().__init__()
         self.config = config
+        use_data_parallel = (
+            multimodal_config.mm_encoder_tp_mode == "data"
+            if multimodal_config
+            else False
+        )
         self.activation_fn = get_act_fn(config.hidden_act)
-        # TODO(Isotr0py): Enable data parallel after we support
-        # disabling TP on parallel linear layer
         self.fc1 = ColumnParallelLinear(
             config.hidden_size,
             config.intermediate_size,
             quant_config=quant_config,
             prefix=f"{prefix}.fc1",
+            disable_tp=use_data_parallel,
         )
         self.fc2 = RowParallelLinear(
             config.intermediate_size,
             config.hidden_size,
             quant_config=quant_config,
             prefix=f"{prefix}.fc2",
+            disable_tp=use_data_parallel,
         )
 
     def forward(self, hidden_states: torch.Tensor) -> torch.Tensor:
@@ -380,9 +349,8 @@ class Siglip2EncoderLayer(nn.Module):
         self,
         config: Siglip2VisionConfig,
         quant_config: QuantizationConfig | None = None,
+        multimodal_config: MultiModalConfig | None = None,
         prefix: str = "",
-        use_data_parallel: bool = False,
-        attn_backend_override: AttentionBackendEnum | None = None,
     ):
         super().__init__()
         self.embed_dim = config.hidden_size
@@ -390,16 +358,15 @@ class Siglip2EncoderLayer(nn.Module):
         self.self_attn = Siglip2Attention(
             config,
             quant_config=quant_config,
+            multimodal_config=multimodal_config,
             prefix=f"{prefix}.self_attn",
-            use_data_parallel=use_data_parallel,
-            attn_backend_override=attn_backend_override,
         )
         self.layer_norm2 = nn.LayerNorm(self.embed_dim, eps=config.layer_norm_eps)
         self.mlp = Siglip2MLP(
             config,
             quant_config=quant_config,
+            multimodal_config=multimodal_config,
             prefix=f"{prefix}.mlp",
-            use_data_parallel=use_data_parallel,
         )
 
     def forward(
@@ -444,9 +411,8 @@ class Siglip2Encoder(nn.Module):
         self,
         config: Siglip2VisionConfig,
         quant_config: QuantizationConfig | None = None,
+        multimodal_config: MultiModalConfig | None = None,
         prefix: str = "",
-        use_data_parallel: bool = False,
-        attn_backend_override: AttentionBackendEnum | None = None,
     ):
         super().__init__()
         self.config = config
@@ -455,9 +421,8 @@ class Siglip2Encoder(nn.Module):
                 Siglip2EncoderLayer(
                     config,
                     quant_config=quant_config,
+                    multimodal_config=multimodal_config,
                     prefix=f"{prefix}.layers.{idx}",
-                    use_data_parallel=use_data_parallel,
-                    attn_backend_override=attn_backend_override,
                 )
                 for idx in range(config.num_hidden_layers)
             ]
@@ -630,9 +595,8 @@ class Siglip2VisionTransformer(nn.Module):
         self,
         config: Siglip2VisionConfig,
         quant_config: QuantizationConfig | None = None,
+        multimodal_config: MultiModalConfig | None = None,
         prefix: str = "",
-        use_data_parallel: bool = False,
-        attn_backend_override: AttentionBackendEnum | None = None,
     ):
         super().__init__()
         self.config = config
@@ -642,9 +606,8 @@ class Siglip2VisionTransformer(nn.Module):
         self.encoder = Siglip2Encoder(
             config,
             quant_config=quant_config,
+            multimodal_config=multimodal_config,
             prefix=f"{prefix}.encoder",
-            use_data_parallel=use_data_parallel,
-            attn_backend_override=attn_backend_override,
         )
         self.post_layernorm = nn.LayerNorm(embed_dim, eps=config.layer_norm_eps)
 
@@ -671,18 +634,16 @@ class Siglip2NavitModel(torch.nn.Module):
         self,
         config: Siglip2VisionConfig,
         quant_config: QuantizationConfig | None = None,
+        multimodal_config: MultiModalConfig | None = None,
         prefix: str = "",
-        use_data_parallel: bool = False,
-        attn_backend_override: AttentionBackendEnum | None = None,
     ):
         super().__init__()
 
         self.vision_model = Siglip2VisionTransformer(
             config,
             quant_config=quant_config,
+            multimodal_config=multimodal_config,
             prefix=f"{prefix}.vision_model",
-            use_data_parallel=use_data_parallel,
-            attn_backend_override=attn_backend_override,
         )
 
     def forward(

vllm/model_executor/models/vision.py

@@ -88,14 +88,17 @@ def get_vit_attn_backend(
     """
     Get the available attention backend for Vision Transformer.
     """
-    if attn_backend_override is not None:
+    attn_backend = attn_backend_override
-        return attn_backend_override
 
     selected_backend = get_current_vllm_config().attention_config.backend
-    if selected_backend is not None:
+    if attn_backend is None:
-        return selected_backend
+        attn_backend = selected_backend
 
-    return current_platform.get_vit_attn_backend(head_size, dtype)
+    return current_platform.get_vit_attn_backend(
+        head_size,
+        dtype,
+        backend=attn_backend,
+    )
 
 
 def should_torch_compile_mm_vit(vllm_config: VllmConfig) -> bool:

vllm/platforms/cuda.py

@@ -7,7 +7,7 @@ pynvml. However, it should not initialize cuda context.
 import os
 from collections.abc import Callable
 from functools import cache, wraps
-from typing import TYPE_CHECKING, TypeVar
+from typing import TYPE_CHECKING, Optional, TypeVar
 
 import torch
 from typing_extensions import ParamSpec
@@ -255,23 +255,6 @@ class CudaPlatformBase(Platform):
         torch.cuda.reset_peak_memory_stats(device)
         return torch.cuda.max_memory_allocated(device)
 
-    @classmethod
-    def get_vit_attn_backend(
-        cls, head_size: int, dtype: torch.dtype
-    ) -> "AttentionBackendEnum":
-        # Try FlashAttention first
-        if (cc := cls.get_device_capability()) and cc.major >= 8:
-            try:
-                backend_class = AttentionBackendEnum.FLASH_ATTN.get_class()
-                if backend_class.supports_head_size(
-                    head_size
-                ) and backend_class.supports_dtype(dtype):
-                    return AttentionBackendEnum.FLASH_ATTN
-            except ImportError:
-                pass
-
-        return AttentionBackendEnum.TORCH_SDPA
-
     @classmethod
     def get_valid_backends(
         cls,
@@ -418,6 +401,41 @@ class CudaPlatformBase(Platform):
 
         return selected_backend.get_path()
 
+    @classmethod
+    def get_supported_vit_attn_backends(cls) -> list["AttentionBackendEnum"]:
+        return [
+            AttentionBackendEnum.TORCH_SDPA,
+            AttentionBackendEnum.FLASH_ATTN,
+        ]
+
+    @classmethod
+    def get_vit_attn_backend(
+        cls,
+        head_size: int,
+        dtype: torch.dtype,
+        backend: Optional["AttentionBackendEnum"] = None,
+    ) -> "AttentionBackendEnum":
+        if backend is not None:
+            assert backend in cls.get_supported_vit_attn_backends(), (
+                f"Backend {backend} is not supported for vit attention. "
+                f"Supported backends are: {cls.get_supported_vit_attn_backends()}"
+            )
+            logger.info_once(f"Using backend {backend} for vit attention")
+            return backend
+
+        # Try FlashAttention first
+        if (cc := cls.get_device_capability()) and cc.major >= 8:
+            try:
+                backend_class = AttentionBackendEnum.FLASH_ATTN.get_class()
+                if backend_class.supports_head_size(
+                    head_size
+                ) and backend_class.supports_dtype(dtype):
+                    return AttentionBackendEnum.FLASH_ATTN
+            except ImportError:
+                pass
+
+        return AttentionBackendEnum.TORCH_SDPA
+
     @classmethod
     def get_punica_wrapper(cls) -> str:
         return "vllm.lora.punica_wrapper.punica_gpu.PunicaWrapperGPU"

vllm/platforms/interface.py

@@ -7,7 +7,7 @@ import platform
 import random
 import sys
 from datetime import timedelta
-from typing import TYPE_CHECKING, Any, NamedTuple
+from typing import TYPE_CHECKING, Any, NamedTuple, Optional
 
 import numpy as np
 import torch
@@ -222,12 +222,6 @@ class Platform:
         with contextlib.suppress(ImportError):
             import vllm._moe_C  # noqa: F401
 
-    @classmethod
-    def get_vit_attn_backend(
-        cls, head_size: int, dtype: torch.dtype
-    ) -> "AttentionBackendEnum":
-        return AttentionBackendEnum.TORCH_SDPA
-
     @classmethod
     def get_attn_backend_cls(
         cls,
@@ -245,6 +239,43 @@ class Platform:
         """Get the attention backend class of a device."""
         return ""
 
+    @classmethod
+    def get_supported_vit_attn_backends(cls) -> list["AttentionBackendEnum"]:
+        return [
+            AttentionBackendEnum.TORCH_SDPA,
+        ]
+
+    @classmethod
+    def get_vit_attn_backend(
+        cls,
+        head_size: int,
+        dtype: torch.dtype,
+        backend: Optional["AttentionBackendEnum"] = None,
+    ) -> "AttentionBackendEnum":
+        """
+        Get the vision attention backend class of a device.
+
+        NOTE: ViT Attention should be checked and override in the platform-specific
+        implementation. we should not override this in any other places, like
+        the model_executor/models/<model_name>.py.
+
+        We check if the backend is None or not:
+            1. If not, check if the backend is supported by the platform.
+            2. If None, continue to the default selection logic.
+        """
+        if backend is not None:
+            assert backend in cls.get_supported_vit_attn_backends(), (
+                f"Backend {backend} is not supported for vit attention"
+                f"Supported backends are: {cls.get_supported_vit_attn_backends()}"
+            )
+            logger.info_once(f"Using backend {backend} for vit attention")
+            return backend
+
+        logger.info_once(
+            f"Using default backend {AttentionBackendEnum.TORCH_SDPA} for vit attention"
+        )
+        return AttentionBackendEnum.TORCH_SDPA
+
     @classmethod
     def get_device_capability(
         cls,

vllm/platforms/rocm.py

@@ -3,7 +3,7 @@
 
 import os
 from functools import cache, lru_cache, wraps
-from typing import TYPE_CHECKING
+from typing import TYPE_CHECKING, Optional
 
 import torch
 
@@ -187,24 +187,6 @@ class RocmPlatform(Platform):
     if not on_gfx9():
         supported_quantization += ["bitsandbytes"]
 
-    @classmethod
-    def get_vit_attn_backend(
-        cls, head_size: int, dtype: torch.dtype
-    ) -> AttentionBackendEnum:
-        from importlib.util import find_spec
-
-        from vllm._aiter_ops import rocm_aiter_ops
-
-        if rocm_aiter_ops.is_mha_enabled():
-            # Note: AITER FA is only supported for Qwen-VL models.
-            # TODO: Add support for other VL models in their model class.
-            return AttentionBackendEnum.ROCM_AITER_FA
-
-        if on_gfx9() and find_spec("flash_attn") is not None:
-            return AttentionBackendEnum.FLASH_ATTN
-
-        return AttentionBackendEnum.TORCH_SDPA
-
     @classmethod
     def get_attn_backend_cls(
         cls,
@@ -322,6 +304,43 @@ class RocmPlatform(Platform):
             "ROCm. Note that V0 attention backends have been removed."
         )
 
+    @classmethod
+    def get_supported_vit_attn_backends(cls) -> list["AttentionBackendEnum"]:
+        return [
+            AttentionBackendEnum.FLASH_ATTN,
+            AttentionBackendEnum.ROCM_AITER_FA,
+            AttentionBackendEnum.TORCH_SDPA,
+        ]
+
+    @classmethod
+    def get_vit_attn_backend(
+        cls,
+        head_size: int,
+        dtype: torch.dtype,
+        backend: Optional["AttentionBackendEnum"] = None,
+    ) -> "AttentionBackendEnum":
+        if backend is not None:
+            assert backend in cls.get_supported_vit_attn_backends(), (
+                f"Backend {backend} is not supported for vit attention. "
+                f"Supported backends are: {cls.get_supported_vit_attn_backends()}"
+            )
+            logger.info_once(f"Using backend {backend} for vit attention")
+            return backend
+
+        from importlib.util import find_spec
+
+        from vllm._aiter_ops import rocm_aiter_ops
+
+        if rocm_aiter_ops.is_mha_enabled():
+            # Note: AITER FA is only supported for Qwen-VL models.
+            # TODO: Add support for other VL models in their model class.
+            return AttentionBackendEnum.ROCM_AITER_FA
+
+        if on_gfx9() and find_spec("flash_attn") is not None:
+            return AttentionBackendEnum.FLASH_ATTN
+
+        return AttentionBackendEnum.TORCH_SDPA
+
     @classmethod
     def set_device(cls, device: torch.device) -> None:
         """

vllm/platforms/tpu.py

@@ -2,7 +2,7 @@
 # SPDX-FileCopyrightText: Copyright contributors to the vLLM project
 
 import contextlib
-from typing import TYPE_CHECKING, cast
+from typing import TYPE_CHECKING, Optional, cast
 
 import torch
 from tpu_info import device
@@ -75,6 +75,32 @@ class TpuPlatform(Platform):
         logger.info("Using Pallas V1 backend.")
         return AttentionBackendEnum.PALLAS.get_path()
 
+    @classmethod
+    def get_supported_vit_attn_backends(cls) -> list["AttentionBackendEnum"]:
+        return [
+            AttentionBackendEnum.PALLAS,
+        ]
+
+    @classmethod
+    def get_vit_attn_backend(
+        cls,
+        head_size: int,
+        dtype: torch.dtype,
+        backend: Optional["AttentionBackendEnum"] = None,
+    ) -> "AttentionBackendEnum":
+        if backend is not None:
+            assert backend in cls.get_supported_vit_attn_backends(), (
+                f"Backend {backend} is not supported for vit attention"
+                f"Supported backends are: {cls.get_supported_vit_attn_backends()}."
+            )
+            logger.info_once(f"Using backend {backend} for vit attention.")
+            return backend
+
+        logger.info_once(
+            f"Using default backend {AttentionBackendEnum.PALLAS} for vit attention."
+        )
+        return AttentionBackendEnum.PALLAS
+
     @classmethod
     def set_device(cls, device: torch.device) -> None:
         """

vllm/platforms/xpu.py

@@ -3,7 +3,7 @@
 
 import contextlib
 import os
-from typing import TYPE_CHECKING
+from typing import TYPE_CHECKING, Optional
 
 import torch
 
@@ -77,6 +77,34 @@ class XPUPlatform(Platform):
         logger.info("Using Flash Attention backend.")
         return AttentionBackendEnum.FLASH_ATTN.get_path()
 
+    @classmethod
+    def get_supported_vit_attn_backends(cls) -> list["AttentionBackendEnum"]:
+        # XPU only supports FLASH_ATTN for vision attention.
+        return [
+            AttentionBackendEnum.FLASH_ATTN,
+        ]
+
+    @classmethod
+    def get_vit_attn_backend(
+        cls,
+        head_size: int,
+        dtype: torch.dtype,
+        backend: Optional["AttentionBackendEnum"] = None,
+    ) -> "AttentionBackendEnum":
+        if backend is not None:
+            assert backend in cls.get_supported_vit_attn_backends(), (
+                f"Backend {backend} is not supported for vit attention. "
+                f"Supported backends are: "
+                f"{cls.get_supported_vit_attn_backends()}."
+            )
+            logger.info_once(f"Using backend {backend} for vit attention")
+            return backend
+
+        logger.info_once(
+            f"Using backend {AttentionBackendEnum.FLASH_ATTN} for vit attention"
+        )
+        return AttentionBackendEnum.FLASH_ATTN
+
     @classmethod
     def set_device(cls, device: torch.device) -> None:
         """
@@ -110,12 +138,6 @@ class XPUPlatform(Platform):
         device_props = torch.xpu.get_device_properties(device_id)
         return device_props.total_memory
 
-    @classmethod
-    def get_vit_attn_backend(
-        cls, head_size: int, dtype: torch.dtype
-    ) -> "AttentionBackendEnum":
-        return AttentionBackendEnum.FLASH_ATTN
-
     @classmethod
     def inference_mode(cls):
         return torch.no_grad()