diff --git a/graphics/composer/2.1/utils/hal/Android.bp b/graphics/composer/2.1/utils/hal/Android.bp
index 7a501fc..ea3666d 100644
--- a/graphics/composer/2.1/utils/hal/Android.bp
+++ b/graphics/composer/2.1/utils/hal/Android.bp
@@ -19,14 +19,12 @@
     vendor_available: true,
     shared_libs: [
         "android.hardware.graphics.composer@2.1",
-        "android.hardware.graphics.mapper@2.0",
-        "android.hardware.graphics.mapper@3.0",
+        "android.hardware.graphics.composer@2.1-resources",
         "libhardware", // TODO remove hwcomposer2.h dependency
     ],
     export_shared_lib_headers: [
         "android.hardware.graphics.composer@2.1",
-        "android.hardware.graphics.mapper@2.0",
-        "android.hardware.graphics.mapper@3.0",
+        "android.hardware.graphics.composer@2.1-resources",
         "libhardware",
     ],
     header_libs: [
diff --git a/graphics/composer/2.1/utils/hal/include/composer-hal/2.1/ComposerClient.h b/graphics/composer/2.1/utils/hal/include/composer-hal/2.1/ComposerClient.h
index 095189f..47ead41 100644
--- a/graphics/composer/2.1/utils/hal/include/composer-hal/2.1/ComposerClient.h
+++ b/graphics/composer/2.1/utils/hal/include/composer-hal/2.1/ComposerClient.h
@@ -27,7 +27,7 @@
 #include <android/hardware/graphics/composer/2.1/IComposerClient.h>
 #include <composer-hal/2.1/ComposerCommandEngine.h>
 #include <composer-hal/2.1/ComposerHal.h>
-#include <composer-hal/2.1/ComposerResources.h>
+#include <composer-resources/2.1/ComposerResources.h>
 #include <log/log.h>
 
 namespace android {
diff --git a/graphics/composer/2.1/utils/hal/include/composer-hal/2.1/ComposerCommandEngine.h b/graphics/composer/2.1/utils/hal/include/composer-hal/2.1/ComposerCommandEngine.h
index d87110a..53b9202 100644
--- a/graphics/composer/2.1/utils/hal/include/composer-hal/2.1/ComposerCommandEngine.h
+++ b/graphics/composer/2.1/utils/hal/include/composer-hal/2.1/ComposerCommandEngine.h
@@ -24,7 +24,7 @@
 
 #include <composer-command-buffer/2.1/ComposerCommandBuffer.h>
 #include <composer-hal/2.1/ComposerHal.h>
-#include <composer-hal/2.1/ComposerResources.h>
+#include <composer-resources/2.1/ComposerResources.h>
 // TODO remove hwcomposer_defs.h dependency
 #include <hardware/hwcomposer_defs.h>
 #include <log/log.h>
@@ -195,7 +195,7 @@
         bool closeFence = true;
 
         const native_handle_t* clientTarget;
-        ComposerResources::ReplacedBufferHandle replacedClientTarget;
+        ComposerResources::ReplacedHandle replacedClientTarget(true);
         auto err = mResources->getDisplayClientTarget(mCurrentDisplay, slot, useCache, rawHandle,
                                                       &clientTarget, &replacedClientTarget);
         if (err == Error::NONE) {
@@ -226,7 +226,7 @@
         bool closeFence = true;
 
         const native_handle_t* outputBuffer;
-        ComposerResources::ReplacedBufferHandle replacedOutputBuffer;
+        ComposerResources::ReplacedHandle replacedOutputBuffer(true);
         auto err = mResources->getDisplayOutputBuffer(mCurrentDisplay, slot, useCache, rawhandle,
                                                       &outputBuffer, &replacedOutputBuffer);
         if (err == Error::NONE) {
@@ -369,7 +369,7 @@
         bool closeFence = true;
 
         const native_handle_t* buffer;
-        ComposerResources::ReplacedBufferHandle replacedBuffer;
+        ComposerResources::ReplacedHandle replacedBuffer(true);
         auto err = mResources->getLayerBuffer(mCurrentDisplay, mCurrentLayer, slot, useCache,
                                               rawHandle, &buffer, &replacedBuffer);
         if (err == Error::NONE) {
@@ -489,7 +489,7 @@
         auto rawHandle = readHandle();
 
         const native_handle_t* stream;
-        ComposerResources::ReplacedStreamHandle replacedStream;
+        ComposerResources::ReplacedHandle replacedStream(false);
         auto err = mResources->getLayerSidebandStream(mCurrentDisplay, mCurrentLayer, rawHandle,
                                                       &stream, &replacedStream);
         if (err == Error::NONE) {
diff --git a/graphics/composer/2.1/utils/hal/include/composer-hal/2.1/ComposerResources.h b/graphics/composer/2.1/utils/hal/include/composer-hal/2.1/ComposerResources.h
deleted file mode 100644
index 18d184e..0000000
--- a/graphics/composer/2.1/utils/hal/include/composer-hal/2.1/ComposerResources.h
+++ /dev/null
@@ -1,592 +0,0 @@
-/*
- * Copyright 2018 The Android Open Source Project
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-#pragma once
-
-#ifndef LOG_TAG
-#warning "ComposerResources.h included without LOG_TAG"
-#endif
-
-#include <memory>
-#include <mutex>
-#include <unordered_map>
-#include <vector>
-
-#include <android/hardware/graphics/mapper/2.0/IMapper.h>
-#include <android/hardware/graphics/mapper/3.0/IMapper.h>
-#include <log/log.h>
-
-namespace android {
-namespace hardware {
-namespace graphics {
-namespace composer {
-namespace V2_1 {
-namespace hal {
-
-// wrapper for IMapper to import buffers and sideband streams
-class ComposerHandleImporter {
-   public:
-    bool init() {
-        mMapper3 = mapper::V3_0::IMapper::getService();
-        if (mMapper3) {
-            return true;
-        }
-        ALOGD_IF(!mMapper3, "failed to get mapper 3.0 service, falling back to mapper 2.0");
-
-        mMapper2 = mapper::V2_0::IMapper::getService();
-        ALOGE_IF(!mMapper2, "failed to get mapper 2.0 service");
-
-        return mMapper2 != nullptr;
-    }
-
-    Error importBuffer(const native_handle_t* rawHandle, const native_handle_t** outBufferHandle) {
-        if (!rawHandle || (!rawHandle->numFds && !rawHandle->numInts)) {
-            *outBufferHandle = nullptr;
-            return Error::NONE;
-        }
-
-        const native_handle_t* bufferHandle;
-        if (mMapper2) {
-            mapper::V2_0::Error error;
-            mMapper2->importBuffer(
-                rawHandle, [&](const auto& tmpError, const auto& tmpBufferHandle) {
-                    error = tmpError;
-                    bufferHandle = static_cast<const native_handle_t*>(tmpBufferHandle);
-                });
-            if (error != mapper::V2_0::Error::NONE) {
-                return Error::NO_RESOURCES;
-            }
-        }
-        if (mMapper3) {
-            mapper::V3_0::Error error;
-            mMapper3->importBuffer(
-                rawHandle, [&](const auto& tmpError, const auto& tmpBufferHandle) {
-                    error = tmpError;
-                    bufferHandle = static_cast<const native_handle_t*>(tmpBufferHandle);
-                });
-            if (error != mapper::V3_0::Error::NONE) {
-                return Error::NO_RESOURCES;
-            }
-        }
-
-        *outBufferHandle = bufferHandle;
-        return Error::NONE;
-    }
-
-    void freeBuffer(const native_handle_t* bufferHandle) {
-        if (bufferHandle) {
-            if (mMapper2) {
-                mMapper2->freeBuffer(
-                    static_cast<void*>(const_cast<native_handle_t*>(bufferHandle)));
-            } else if (mMapper3) {
-                mMapper3->freeBuffer(
-                    static_cast<void*>(const_cast<native_handle_t*>(bufferHandle)));
-            }
-        }
-    }
-
-    Error importStream(const native_handle_t* rawHandle, const native_handle_t** outStreamHandle) {
-        const native_handle_t* streamHandle = nullptr;
-        if (rawHandle) {
-            streamHandle = native_handle_clone(rawHandle);
-            if (!streamHandle) {
-                return Error::NO_RESOURCES;
-            }
-        }
-
-        *outStreamHandle = streamHandle;
-        return Error::NONE;
-    }
-
-    void freeStream(const native_handle_t* streamHandle) {
-        if (streamHandle) {
-            native_handle_close(streamHandle);
-            native_handle_delete(const_cast<native_handle_t*>(streamHandle));
-        }
-    }
-
-   private:
-    sp<mapper::V2_0::IMapper> mMapper2;
-    sp<mapper::V3_0::IMapper> mMapper3;
-};
-
-class ComposerHandleCache {
-   public:
-    enum class HandleType {
-        INVALID,
-        BUFFER,
-        STREAM,
-    };
-
-    ComposerHandleCache(ComposerHandleImporter& importer, HandleType type, uint32_t cacheSize)
-        : mImporter(importer), mHandleType(type), mHandles(cacheSize, nullptr) {}
-
-    // must be initialized later with initCache
-    ComposerHandleCache(ComposerHandleImporter& importer) : mImporter(importer) {}
-
-    ~ComposerHandleCache() {
-        switch (mHandleType) {
-            case HandleType::BUFFER:
-                for (auto handle : mHandles) {
-                    mImporter.freeBuffer(handle);
-                }
-                break;
-            case HandleType::STREAM:
-                for (auto handle : mHandles) {
-                    mImporter.freeStream(handle);
-                }
-                break;
-            default:
-                break;
-        }
-    }
-
-    ComposerHandleCache(const ComposerHandleCache&) = delete;
-    ComposerHandleCache& operator=(const ComposerHandleCache&) = delete;
-
-    bool initCache(HandleType type, uint32_t cacheSize) {
-        // already initialized
-        if (mHandleType != HandleType::INVALID) {
-            return false;
-        }
-
-        mHandleType = type;
-        mHandles.resize(cacheSize, nullptr);
-
-        return true;
-    }
-
-    Error lookupCache(uint32_t slot, const native_handle_t** outHandle) {
-        if (slot >= 0 && slot < mHandles.size()) {
-            *outHandle = mHandles[slot];
-            return Error::NONE;
-        } else {
-            return Error::BAD_PARAMETER;
-        }
-    }
-
-    Error updateCache(uint32_t slot, const native_handle_t* handle,
-                      const native_handle** outReplacedHandle) {
-        if (slot >= 0 && slot < mHandles.size()) {
-            auto& cachedHandle = mHandles[slot];
-            *outReplacedHandle = cachedHandle;
-            cachedHandle = handle;
-            return Error::NONE;
-        } else {
-            return Error::BAD_PARAMETER;
-        }
-    }
-
-    // when fromCache is true, look up in the cache; otherwise, update the cache
-    Error getHandle(uint32_t slot, bool fromCache, const native_handle_t* inHandle,
-                    const native_handle_t** outHandle, const native_handle** outReplacedHandle) {
-        if (fromCache) {
-            *outReplacedHandle = nullptr;
-            return lookupCache(slot, outHandle);
-        } else {
-            *outHandle = inHandle;
-            return updateCache(slot, inHandle, outReplacedHandle);
-        }
-    }
-
-   private:
-    ComposerHandleImporter& mImporter;
-    HandleType mHandleType = HandleType::INVALID;
-    std::vector<const native_handle_t*> mHandles;
-};
-
-// layer resource
-class ComposerLayerResource {
-   public:
-    ComposerLayerResource(ComposerHandleImporter& importer, uint32_t bufferCacheSize)
-        : mBufferCache(importer, ComposerHandleCache::HandleType::BUFFER, bufferCacheSize),
-          mSidebandStreamCache(importer, ComposerHandleCache::HandleType::STREAM, 1) {}
-
-    virtual ~ComposerLayerResource() = default;
-
-    Error getBuffer(uint32_t slot, bool fromCache, const native_handle_t* inHandle,
-                    const native_handle_t** outHandle, const native_handle** outReplacedHandle) {
-        return mBufferCache.getHandle(slot, fromCache, inHandle, outHandle, outReplacedHandle);
-    }
-
-    Error getSidebandStream(uint32_t slot, bool fromCache, const native_handle_t* inHandle,
-                            const native_handle_t** outHandle,
-                            const native_handle** outReplacedHandle) {
-        return mSidebandStreamCache.getHandle(slot, fromCache, inHandle, outHandle,
-                                              outReplacedHandle);
-    }
-
-   protected:
-    ComposerHandleCache mBufferCache;
-    ComposerHandleCache mSidebandStreamCache;
-};
-
-// display resource
-class ComposerDisplayResource {
-   public:
-    enum class DisplayType {
-        PHYSICAL,
-        VIRTUAL,
-    };
-
-    virtual ~ComposerDisplayResource() = default;
-
-    ComposerDisplayResource(DisplayType type, ComposerHandleImporter& importer,
-                            uint32_t outputBufferCacheSize)
-        : mType(type),
-          mClientTargetCache(importer),
-          mOutputBufferCache(importer, ComposerHandleCache::HandleType::BUFFER,
-                             outputBufferCacheSize),
-          mMustValidate(true) {}
-
-    bool initClientTargetCache(uint32_t cacheSize) {
-        return mClientTargetCache.initCache(ComposerHandleCache::HandleType::BUFFER, cacheSize);
-    }
-
-    bool isVirtual() const { return mType == DisplayType::VIRTUAL; }
-
-    Error getClientTarget(uint32_t slot, bool fromCache, const native_handle_t* inHandle,
-                          const native_handle_t** outHandle,
-                          const native_handle** outReplacedHandle) {
-        return mClientTargetCache.getHandle(slot, fromCache, inHandle, outHandle,
-                                            outReplacedHandle);
-    }
-
-    Error getOutputBuffer(uint32_t slot, bool fromCache, const native_handle_t* inHandle,
-                          const native_handle_t** outHandle,
-                          const native_handle** outReplacedHandle) {
-        return mOutputBufferCache.getHandle(slot, fromCache, inHandle, outHandle,
-                                            outReplacedHandle);
-    }
-
-    bool addLayer(Layer layer, std::unique_ptr<ComposerLayerResource> layerResource) {
-        auto result = mLayerResources.emplace(layer, std::move(layerResource));
-        return result.second;
-    }
-
-    bool removeLayer(Layer layer) { return mLayerResources.erase(layer) > 0; }
-
-    ComposerLayerResource* findLayerResource(Layer layer) {
-        auto layerIter = mLayerResources.find(layer);
-        if (layerIter == mLayerResources.end()) {
-            return nullptr;
-        }
-
-        return layerIter->second.get();
-    }
-
-    std::vector<Layer> getLayers() const {
-        std::vector<Layer> layers;
-        layers.reserve(mLayerResources.size());
-        for (const auto& layerKey : mLayerResources) {
-            layers.push_back(layerKey.first);
-        }
-        return layers;
-    }
-
-    void setMustValidateState(bool mustValidate) { mMustValidate = mustValidate; }
-
-    bool mustValidate() const { return mMustValidate; }
-
-   protected:
-    const DisplayType mType;
-    ComposerHandleCache mClientTargetCache;
-    ComposerHandleCache mOutputBufferCache;
-    bool mMustValidate;
-
-    std::unordered_map<Layer, std::unique_ptr<ComposerLayerResource>> mLayerResources;
-};
-
-class ComposerResources {
-   private:
-    template <bool isBuffer>
-    class ReplacedHandle;
-
-   public:
-    static std::unique_ptr<ComposerResources> create() {
-        auto resources = std::make_unique<ComposerResources>();
-        return resources->init() ? std::move(resources) : nullptr;
-    }
-
-    ComposerResources() = default;
-    virtual ~ComposerResources() = default;
-
-    bool init() { return mImporter.init(); }
-
-    using RemoveDisplay =
-        std::function<void(Display display, bool isVirtual, const std::vector<Layer>& layers)>;
-    void clear(RemoveDisplay removeDisplay) {
-        std::lock_guard<std::mutex> lock(mDisplayResourcesMutex);
-        for (const auto& displayKey : mDisplayResources) {
-            Display display = displayKey.first;
-            const ComposerDisplayResource& displayResource = *displayKey.second;
-            removeDisplay(display, displayResource.isVirtual(), displayResource.getLayers());
-        }
-        mDisplayResources.clear();
-    }
-
-    Error addPhysicalDisplay(Display display) {
-        auto displayResource =
-            createDisplayResource(ComposerDisplayResource::DisplayType::PHYSICAL, 0);
-
-        std::lock_guard<std::mutex> lock(mDisplayResourcesMutex);
-        auto result = mDisplayResources.emplace(display, std::move(displayResource));
-        return result.second ? Error::NONE : Error::BAD_DISPLAY;
-    }
-
-    Error addVirtualDisplay(Display display, uint32_t outputBufferCacheSize) {
-        auto displayResource = createDisplayResource(ComposerDisplayResource::DisplayType::VIRTUAL,
-                                                     outputBufferCacheSize);
-
-        std::lock_guard<std::mutex> lock(mDisplayResourcesMutex);
-        auto result = mDisplayResources.emplace(display, std::move(displayResource));
-        return result.second ? Error::NONE : Error::BAD_DISPLAY;
-    }
-
-    Error removeDisplay(Display display) {
-        std::lock_guard<std::mutex> lock(mDisplayResourcesMutex);
-        return mDisplayResources.erase(display) > 0 ? Error::NONE : Error::BAD_DISPLAY;
-    }
-
-    Error setDisplayClientTargetCacheSize(Display display, uint32_t clientTargetCacheSize) {
-        std::lock_guard<std::mutex> lock(mDisplayResourcesMutex);
-        ComposerDisplayResource* displayResource = findDisplayResourceLocked(display);
-        if (!displayResource) {
-            return Error::BAD_DISPLAY;
-        }
-
-        return displayResource->initClientTargetCache(clientTargetCacheSize) ? Error::NONE
-                                                                             : Error::BAD_PARAMETER;
-    }
-
-    Error addLayer(Display display, Layer layer, uint32_t bufferCacheSize) {
-        auto layerResource = createLayerResource(bufferCacheSize);
-
-        std::lock_guard<std::mutex> lock(mDisplayResourcesMutex);
-        ComposerDisplayResource* displayResource = findDisplayResourceLocked(display);
-        if (!displayResource) {
-            return Error::BAD_DISPLAY;
-        }
-
-        return displayResource->addLayer(layer, std::move(layerResource)) ? Error::NONE
-                                                                          : Error::BAD_LAYER;
-    }
-
-    Error removeLayer(Display display, Layer layer) {
-        std::lock_guard<std::mutex> lock(mDisplayResourcesMutex);
-        ComposerDisplayResource* displayResource = findDisplayResourceLocked(display);
-        if (!displayResource) {
-            return Error::BAD_DISPLAY;
-        }
-
-        return displayResource->removeLayer(layer) ? Error::NONE : Error::BAD_LAYER;
-    }
-
-    using ReplacedBufferHandle = ReplacedHandle<true>;
-    using ReplacedStreamHandle = ReplacedHandle<false>;
-
-    Error getDisplayClientTarget(Display display, uint32_t slot, bool fromCache,
-                                 const native_handle_t* rawHandle,
-                                 const native_handle_t** outBufferHandle,
-                                 ReplacedBufferHandle* outReplacedBuffer) {
-        return getHandle<Cache::CLIENT_TARGET>(display, 0, slot, fromCache, rawHandle,
-                                               outBufferHandle, outReplacedBuffer);
-    }
-
-    Error getDisplayOutputBuffer(Display display, uint32_t slot, bool fromCache,
-                                 const native_handle_t* rawHandle,
-                                 const native_handle_t** outBufferHandle,
-                                 ReplacedBufferHandle* outReplacedBuffer) {
-        return getHandle<Cache::OUTPUT_BUFFER>(display, 0, slot, fromCache, rawHandle,
-                                               outBufferHandle, outReplacedBuffer);
-    }
-
-    Error getLayerBuffer(Display display, Layer layer, uint32_t slot, bool fromCache,
-                         const native_handle_t* rawHandle, const native_handle_t** outBufferHandle,
-                         ReplacedBufferHandle* outReplacedBuffer) {
-        return getHandle<Cache::LAYER_BUFFER>(display, layer, slot, fromCache, rawHandle,
-                                              outBufferHandle, outReplacedBuffer);
-    }
-
-    Error getLayerSidebandStream(Display display, Layer layer, const native_handle_t* rawHandle,
-                                 const native_handle_t** outStreamHandle,
-                                 ReplacedStreamHandle* outReplacedStream) {
-        return getHandle<Cache::LAYER_SIDEBAND_STREAM>(display, layer, 0, false, rawHandle,
-                                                       outStreamHandle, outReplacedStream);
-    }
-
-    void setDisplayMustValidateState(Display display, bool mustValidate) {
-        std::lock_guard<std::mutex> lock(mDisplayResourcesMutex);
-        auto* displayResource = findDisplayResourceLocked(display);
-        if (displayResource) {
-            displayResource->setMustValidateState(mustValidate);
-        }
-    }
-
-    bool mustValidateDisplay(Display display) {
-        std::lock_guard<std::mutex> lock(mDisplayResourcesMutex);
-        auto* displayResource = findDisplayResourceLocked(display);
-        if (displayResource) {
-            return displayResource->mustValidate();
-        }
-        return false;
-    }
-
-   protected:
-    virtual std::unique_ptr<ComposerDisplayResource> createDisplayResource(
-        ComposerDisplayResource::DisplayType type, uint32_t outputBufferCacheSize) {
-        return std::make_unique<ComposerDisplayResource>(type, mImporter, outputBufferCacheSize);
-    }
-
-    virtual std::unique_ptr<ComposerLayerResource> createLayerResource(uint32_t bufferCacheSize) {
-        return std::make_unique<ComposerLayerResource>(mImporter, bufferCacheSize);
-    }
-
-    ComposerDisplayResource* findDisplayResourceLocked(Display display) {
-        auto iter = mDisplayResources.find(display);
-        if (iter == mDisplayResources.end()) {
-            return nullptr;
-        }
-        return iter->second.get();
-    }
-
-    ComposerHandleImporter mImporter;
-
-    std::mutex mDisplayResourcesMutex;
-    std::unordered_map<Display, std::unique_ptr<ComposerDisplayResource>> mDisplayResources;
-
-   private:
-    enum class Cache {
-        CLIENT_TARGET,
-        OUTPUT_BUFFER,
-        LAYER_BUFFER,
-        LAYER_SIDEBAND_STREAM,
-    };
-
-    // When a buffer in the cache is replaced by a new one, we must keep it
-    // alive until it has been replaced in ComposerHal.
-    template <bool isBuffer>
-    class ReplacedHandle {
-       public:
-        ReplacedHandle() = default;
-        ReplacedHandle(const ReplacedHandle&) = delete;
-        ReplacedHandle& operator=(const ReplacedHandle&) = delete;
-
-        ~ReplacedHandle() { reset(); }
-
-        void reset(ComposerHandleImporter* importer = nullptr,
-                   const native_handle_t* handle = nullptr) {
-            if (mHandle) {
-                if (isBuffer) {
-                    mImporter->freeBuffer(mHandle);
-                } else {
-                    mImporter->freeStream(mHandle);
-                }
-            }
-
-            mImporter = importer;
-            mHandle = handle;
-        }
-
-       private:
-        ComposerHandleImporter* mImporter = nullptr;
-        const native_handle_t* mHandle = nullptr;
-    };
-
-    template <Cache cache, bool isBuffer>
-    Error getHandle(Display display, Layer layer, uint32_t slot, bool fromCache,
-                    const native_handle_t* rawHandle, const native_handle_t** outHandle,
-                    ReplacedHandle<isBuffer>* outReplacedHandle) {
-        Error error;
-
-        // import the raw handle (or ignore raw handle when fromCache is true)
-        const native_handle_t* importedHandle = nullptr;
-        if (!fromCache) {
-            error = (isBuffer) ? mImporter.importBuffer(rawHandle, &importedHandle)
-                               : mImporter.importStream(rawHandle, &importedHandle);
-            if (error != Error::NONE) {
-                return error;
-            }
-        }
-
-        std::lock_guard<std::mutex> lock(mDisplayResourcesMutex);
-
-        // find display/layer resource
-        const bool needLayerResource =
-            (cache == Cache::LAYER_BUFFER || cache == Cache::LAYER_SIDEBAND_STREAM);
-        ComposerDisplayResource* displayResource = findDisplayResourceLocked(display);
-        ComposerLayerResource* layerResource = (displayResource && needLayerResource)
-                                                   ? displayResource->findLayerResource(layer)
-                                                   : nullptr;
-
-        // lookup or update cache
-        const native_handle_t* replacedHandle = nullptr;
-        if (displayResource && (!needLayerResource || layerResource)) {
-            switch (cache) {
-                case Cache::CLIENT_TARGET:
-                    error = displayResource->getClientTarget(slot, fromCache, importedHandle,
-                                                             outHandle, &replacedHandle);
-                    break;
-                case Cache::OUTPUT_BUFFER:
-                    error = displayResource->getOutputBuffer(slot, fromCache, importedHandle,
-                                                             outHandle, &replacedHandle);
-                    break;
-                case Cache::LAYER_BUFFER:
-                    error = layerResource->getBuffer(slot, fromCache, importedHandle, outHandle,
-                                                     &replacedHandle);
-                    break;
-                case Cache::LAYER_SIDEBAND_STREAM:
-                    error = layerResource->getSidebandStream(slot, fromCache, importedHandle,
-                                                             outHandle, &replacedHandle);
-                    break;
-                default:
-                    error = Error::BAD_PARAMETER;
-                    break;
-            }
-
-            if (error != Error::NONE) {
-                ALOGW("invalid cache %d slot %d", int(cache), int(slot));
-            }
-        } else if (!displayResource) {
-            error = Error::BAD_DISPLAY;
-        } else {
-            error = Error::BAD_LAYER;
-        }
-
-        // clean up on errors
-        if (error != Error::NONE) {
-            if (!fromCache) {
-                if (isBuffer) {
-                    mImporter.freeBuffer(importedHandle);
-                } else {
-                    mImporter.freeStream(importedHandle);
-                }
-            }
-            return error;
-        }
-
-        outReplacedHandle->reset(&mImporter, replacedHandle);
-
-        return Error::NONE;
-    }
-};
-
-}  // namespace hal
-}  // namespace V2_1
-}  // namespace composer
-}  // namespace graphics
-}  // namespace hardware
-}  // namespace android
diff --git a/graphics/composer/2.1/utils/resources/Android.bp b/graphics/composer/2.1/utils/resources/Android.bp
new file mode 100644
index 0000000..e7ba458
--- /dev/null
+++ b/graphics/composer/2.1/utils/resources/Android.bp
@@ -0,0 +1,49 @@
+//
+// Copyright (C) 2019 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+cc_library_shared {
+    name: "android.hardware.graphics.composer@2.1-resources",
+    defaults: ["hidl_defaults"],
+    vendor_available: true,
+    shared_libs: [
+        "android.hardware.graphics.composer@2.1",
+        "android.hardware.graphics.mapper@2.0",
+        "android.hardware.graphics.mapper@3.0",
+        "libcutils",
+        "libhardware", // TODO remove hwcomposer2.h dependency
+        "libhidlbase",
+        "liblog",
+        "libutils",
+    ],
+    export_shared_lib_headers: [
+        "android.hardware.graphics.composer@2.1",
+        "android.hardware.graphics.mapper@2.0",
+        "android.hardware.graphics.mapper@3.0",
+        "libhardware",
+        "libhidlbase",
+        "liblog",
+        "libutils",
+    ],
+    header_libs: [
+        "android.hardware.graphics.composer@2.1-command-buffer",
+    ],
+    export_header_lib_headers: [
+        "android.hardware.graphics.composer@2.1-command-buffer",
+    ],
+    export_include_dirs: ["include"],
+    srcs: [
+        "ComposerResources.cpp",
+    ],
+}
diff --git a/graphics/composer/2.1/utils/resources/ComposerResources.cpp b/graphics/composer/2.1/utils/resources/ComposerResources.cpp
new file mode 100644
index 0000000..d28eedc
--- /dev/null
+++ b/graphics/composer/2.1/utils/resources/ComposerResources.cpp
@@ -0,0 +1,485 @@
+/*
+ * Copyright 2019 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#define LOG_TAG "ComposerResources"
+
+#include "composer-resources/2.1/ComposerResources.h"
+
+namespace android {
+namespace hardware {
+namespace graphics {
+namespace composer {
+namespace V2_1 {
+namespace hal {
+
+bool ComposerHandleImporter::init() {
+    mMapper3 = mapper::V3_0::IMapper::getService();
+    if (mMapper3) {
+        return true;
+    }
+    ALOGI_IF(!mMapper3, "failed to get mapper 3.0 service, falling back to mapper 2.0");
+
+    mMapper2 = mapper::V2_0::IMapper::getService();
+    ALOGE_IF(!mMapper2, "failed to get mapper 2.0 service");
+
+    return mMapper2 != nullptr;
+}
+
+Error ComposerHandleImporter::importBuffer(const native_handle_t* rawHandle,
+                                           const native_handle_t** outBufferHandle) {
+    if (!rawHandle || (!rawHandle->numFds && !rawHandle->numInts)) {
+        *outBufferHandle = nullptr;
+        return Error::NONE;
+    }
+
+    const native_handle_t* bufferHandle;
+    if (mMapper2) {
+        mapper::V2_0::Error error;
+        mMapper2->importBuffer(rawHandle, [&](const auto& tmpError, const auto& tmpBufferHandle) {
+            error = tmpError;
+            bufferHandle = static_cast<const native_handle_t*>(tmpBufferHandle);
+        });
+        if (error != mapper::V2_0::Error::NONE) {
+            return Error::NO_RESOURCES;
+        }
+    }
+    if (mMapper3) {
+        mapper::V3_0::Error error;
+        mMapper3->importBuffer(rawHandle, [&](const auto& tmpError, const auto& tmpBufferHandle) {
+            error = tmpError;
+            bufferHandle = static_cast<const native_handle_t*>(tmpBufferHandle);
+        });
+        if (error != mapper::V3_0::Error::NONE) {
+            return Error::NO_RESOURCES;
+        }
+    }
+
+    *outBufferHandle = bufferHandle;
+    return Error::NONE;
+}
+
+void ComposerHandleImporter::freeBuffer(const native_handle_t* bufferHandle) {
+    if (bufferHandle) {
+        if (mMapper2) {
+            mMapper2->freeBuffer(static_cast<void*>(const_cast<native_handle_t*>(bufferHandle)));
+        } else if (mMapper3) {
+            mMapper3->freeBuffer(static_cast<void*>(const_cast<native_handle_t*>(bufferHandle)));
+        }
+    }
+}
+
+Error ComposerHandleImporter::importStream(const native_handle_t* rawHandle,
+                                           const native_handle_t** outStreamHandle) {
+    const native_handle_t* streamHandle = nullptr;
+    if (rawHandle) {
+        streamHandle = native_handle_clone(rawHandle);
+        if (!streamHandle) {
+            return Error::NO_RESOURCES;
+        }
+    }
+
+    *outStreamHandle = streamHandle;
+    return Error::NONE;
+}
+
+void ComposerHandleImporter::freeStream(const native_handle_t* streamHandle) {
+    if (streamHandle) {
+        native_handle_close(streamHandle);
+        native_handle_delete(const_cast<native_handle_t*>(streamHandle));
+    }
+}
+
+ComposerHandleCache::ComposerHandleCache(ComposerHandleImporter& importer, HandleType type,
+                                         uint32_t cacheSize)
+    : mImporter(importer), mHandleType(type), mHandles(cacheSize, nullptr) {}
+
+// must be initialized later with initCache
+ComposerHandleCache::ComposerHandleCache(ComposerHandleImporter& importer) : mImporter(importer) {}
+
+ComposerHandleCache::~ComposerHandleCache() {
+    switch (mHandleType) {
+        case HandleType::BUFFER:
+            for (auto handle : mHandles) {
+                mImporter.freeBuffer(handle);
+            }
+            break;
+        case HandleType::STREAM:
+            for (auto handle : mHandles) {
+                mImporter.freeStream(handle);
+            }
+            break;
+        default:
+            break;
+    }
+}
+
+bool ComposerHandleCache::initCache(HandleType type, uint32_t cacheSize) {
+    // already initialized
+    if (mHandleType != HandleType::INVALID) {
+        return false;
+    }
+
+    mHandleType = type;
+    mHandles.resize(cacheSize, nullptr);
+
+    return true;
+}
+
+Error ComposerHandleCache::lookupCache(uint32_t slot, const native_handle_t** outHandle) {
+    if (slot >= 0 && slot < mHandles.size()) {
+        *outHandle = mHandles[slot];
+        return Error::NONE;
+    } else {
+        return Error::BAD_PARAMETER;
+    }
+}
+
+Error ComposerHandleCache::updateCache(uint32_t slot, const native_handle_t* handle,
+                                       const native_handle** outReplacedHandle) {
+    if (slot >= 0 && slot < mHandles.size()) {
+        auto& cachedHandle = mHandles[slot];
+        *outReplacedHandle = cachedHandle;
+        cachedHandle = handle;
+        return Error::NONE;
+    } else {
+        return Error::BAD_PARAMETER;
+    }
+}
+
+// when fromCache is true, look up in the cache; otherwise, update the cache
+Error ComposerHandleCache::getHandle(uint32_t slot, bool fromCache, const native_handle_t* inHandle,
+                                     const native_handle_t** outHandle,
+                                     const native_handle** outReplacedHandle) {
+    if (fromCache) {
+        *outReplacedHandle = nullptr;
+        return lookupCache(slot, outHandle);
+    } else {
+        *outHandle = inHandle;
+        return updateCache(slot, inHandle, outReplacedHandle);
+    }
+}
+
+ComposerLayerResource::ComposerLayerResource(ComposerHandleImporter& importer,
+                                             uint32_t bufferCacheSize)
+    : mBufferCache(importer, ComposerHandleCache::HandleType::BUFFER, bufferCacheSize),
+      mSidebandStreamCache(importer, ComposerHandleCache::HandleType::STREAM, 1) {}
+
+Error ComposerLayerResource::getBuffer(uint32_t slot, bool fromCache,
+                                       const native_handle_t* inHandle,
+                                       const native_handle_t** outHandle,
+                                       const native_handle** outReplacedHandle) {
+    return mBufferCache.getHandle(slot, fromCache, inHandle, outHandle, outReplacedHandle);
+}
+
+Error ComposerLayerResource::getSidebandStream(uint32_t slot, bool fromCache,
+                                               const native_handle_t* inHandle,
+                                               const native_handle_t** outHandle,
+                                               const native_handle** outReplacedHandle) {
+    return mSidebandStreamCache.getHandle(slot, fromCache, inHandle, outHandle, outReplacedHandle);
+}
+
+ComposerDisplayResource::ComposerDisplayResource(DisplayType type, ComposerHandleImporter& importer,
+                                                 uint32_t outputBufferCacheSize)
+    : mType(type),
+      mClientTargetCache(importer),
+      mOutputBufferCache(importer, ComposerHandleCache::HandleType::BUFFER, outputBufferCacheSize),
+      mMustValidate(true) {}
+
+bool ComposerDisplayResource::initClientTargetCache(uint32_t cacheSize) {
+    return mClientTargetCache.initCache(ComposerHandleCache::HandleType::BUFFER, cacheSize);
+}
+
+bool ComposerDisplayResource::isVirtual() const {
+    return mType == DisplayType::VIRTUAL;
+}
+
+Error ComposerDisplayResource::getClientTarget(uint32_t slot, bool fromCache,
+                                               const native_handle_t* inHandle,
+                                               const native_handle_t** outHandle,
+                                               const native_handle** outReplacedHandle) {
+    return mClientTargetCache.getHandle(slot, fromCache, inHandle, outHandle, outReplacedHandle);
+}
+
+Error ComposerDisplayResource::getOutputBuffer(uint32_t slot, bool fromCache,
+                                               const native_handle_t* inHandle,
+                                               const native_handle_t** outHandle,
+                                               const native_handle** outReplacedHandle) {
+    return mOutputBufferCache.getHandle(slot, fromCache, inHandle, outHandle, outReplacedHandle);
+}
+
+bool ComposerDisplayResource::addLayer(Layer layer,
+                                       std::unique_ptr<ComposerLayerResource> layerResource) {
+    auto result = mLayerResources.emplace(layer, std::move(layerResource));
+    return result.second;
+}
+
+bool ComposerDisplayResource::removeLayer(Layer layer) {
+    return mLayerResources.erase(layer) > 0;
+}
+
+ComposerLayerResource* ComposerDisplayResource::findLayerResource(Layer layer) {
+    auto layerIter = mLayerResources.find(layer);
+    if (layerIter == mLayerResources.end()) {
+        return nullptr;
+    }
+
+    return layerIter->second.get();
+}
+
+std::vector<Layer> ComposerDisplayResource::getLayers() const {
+    std::vector<Layer> layers;
+    layers.reserve(mLayerResources.size());
+    for (const auto& layerKey : mLayerResources) {
+        layers.push_back(layerKey.first);
+    }
+    return layers;
+}
+
+void ComposerDisplayResource::setMustValidateState(bool mustValidate) {
+    mMustValidate = mustValidate;
+}
+
+bool ComposerDisplayResource::mustValidate() const {
+    return mMustValidate;
+}
+
+std::unique_ptr<ComposerResources> ComposerResources::create() {
+    auto resources = std::make_unique<ComposerResources>();
+    return resources->init() ? std::move(resources) : nullptr;
+}
+
+bool ComposerResources::init() {
+    return mImporter.init();
+}
+
+void ComposerResources::clear(RemoveDisplay removeDisplay) {
+    std::lock_guard<std::mutex> lock(mDisplayResourcesMutex);
+    for (const auto& displayKey : mDisplayResources) {
+        Display display = displayKey.first;
+        const ComposerDisplayResource& displayResource = *displayKey.second;
+        removeDisplay(display, displayResource.isVirtual(), displayResource.getLayers());
+    }
+    mDisplayResources.clear();
+}
+
+Error ComposerResources::addPhysicalDisplay(Display display) {
+    auto displayResource = createDisplayResource(ComposerDisplayResource::DisplayType::PHYSICAL, 0);
+
+    std::lock_guard<std::mutex> lock(mDisplayResourcesMutex);
+    auto result = mDisplayResources.emplace(display, std::move(displayResource));
+    return result.second ? Error::NONE : Error::BAD_DISPLAY;
+}
+
+Error ComposerResources::addVirtualDisplay(Display display, uint32_t outputBufferCacheSize) {
+    auto displayResource = createDisplayResource(ComposerDisplayResource::DisplayType::VIRTUAL,
+                                                 outputBufferCacheSize);
+
+    std::lock_guard<std::mutex> lock(mDisplayResourcesMutex);
+    auto result = mDisplayResources.emplace(display, std::move(displayResource));
+    return result.second ? Error::NONE : Error::BAD_DISPLAY;
+}
+
+Error ComposerResources::removeDisplay(Display display) {
+    std::lock_guard<std::mutex> lock(mDisplayResourcesMutex);
+    return mDisplayResources.erase(display) > 0 ? Error::NONE : Error::BAD_DISPLAY;
+}
+
+Error ComposerResources::setDisplayClientTargetCacheSize(Display display,
+                                                         uint32_t clientTargetCacheSize) {
+    std::lock_guard<std::mutex> lock(mDisplayResourcesMutex);
+    ComposerDisplayResource* displayResource = findDisplayResourceLocked(display);
+    if (!displayResource) {
+        return Error::BAD_DISPLAY;
+    }
+
+    return displayResource->initClientTargetCache(clientTargetCacheSize) ? Error::NONE
+                                                                         : Error::BAD_PARAMETER;
+}
+
+Error ComposerResources::addLayer(Display display, Layer layer, uint32_t bufferCacheSize) {
+    auto layerResource = createLayerResource(bufferCacheSize);
+
+    std::lock_guard<std::mutex> lock(mDisplayResourcesMutex);
+    ComposerDisplayResource* displayResource = findDisplayResourceLocked(display);
+    if (!displayResource) {
+        return Error::BAD_DISPLAY;
+    }
+
+    return displayResource->addLayer(layer, std::move(layerResource)) ? Error::NONE
+                                                                      : Error::BAD_LAYER;
+}
+
+Error ComposerResources::removeLayer(Display display, Layer layer) {
+    std::lock_guard<std::mutex> lock(mDisplayResourcesMutex);
+    ComposerDisplayResource* displayResource = findDisplayResourceLocked(display);
+    if (!displayResource) {
+        return Error::BAD_DISPLAY;
+    }
+
+    return displayResource->removeLayer(layer) ? Error::NONE : Error::BAD_LAYER;
+}
+
+Error ComposerResources::getDisplayClientTarget(Display display, uint32_t slot, bool fromCache,
+                                                const native_handle_t* rawHandle,
+                                                const native_handle_t** outBufferHandle,
+                                                ReplacedHandle* outReplacedBuffer) {
+    return getHandle(display, 0, slot, Cache::CLIENT_TARGET, fromCache, rawHandle, outBufferHandle,
+                     outReplacedBuffer);
+}
+
+Error ComposerResources::getDisplayOutputBuffer(Display display, uint32_t slot, bool fromCache,
+                                                const native_handle_t* rawHandle,
+                                                const native_handle_t** outBufferHandle,
+                                                ReplacedHandle* outReplacedBuffer) {
+    return getHandle(display, 0, slot, Cache::OUTPUT_BUFFER, fromCache, rawHandle, outBufferHandle,
+                     outReplacedBuffer);
+}
+
+Error ComposerResources::getLayerBuffer(Display display, Layer layer, uint32_t slot, bool fromCache,
+                                        const native_handle_t* rawHandle,
+                                        const native_handle_t** outBufferHandle,
+                                        ReplacedHandle* outReplacedBuffer) {
+    return getHandle(display, layer, slot, Cache::LAYER_BUFFER, fromCache, rawHandle,
+                     outBufferHandle, outReplacedBuffer);
+}
+
+Error ComposerResources::getLayerSidebandStream(Display display, Layer layer,
+                                                const native_handle_t* rawHandle,
+                                                const native_handle_t** outStreamHandle,
+                                                ReplacedHandle* outReplacedStream) {
+    return getHandle(display, layer, 0, Cache::LAYER_SIDEBAND_STREAM, false, rawHandle,
+                     outStreamHandle, outReplacedStream);
+}
+
+void ComposerResources::setDisplayMustValidateState(Display display, bool mustValidate) {
+    std::lock_guard<std::mutex> lock(mDisplayResourcesMutex);
+    auto* displayResource = findDisplayResourceLocked(display);
+    if (displayResource) {
+        displayResource->setMustValidateState(mustValidate);
+    }
+}
+
+bool ComposerResources::mustValidateDisplay(Display display) {
+    std::lock_guard<std::mutex> lock(mDisplayResourcesMutex);
+    auto* displayResource = findDisplayResourceLocked(display);
+    if (displayResource) {
+        return displayResource->mustValidate();
+    }
+    return false;
+}
+
+std::unique_ptr<ComposerDisplayResource> ComposerResources::createDisplayResource(
+        ComposerDisplayResource::DisplayType type, uint32_t outputBufferCacheSize) {
+    return std::make_unique<ComposerDisplayResource>(type, mImporter, outputBufferCacheSize);
+}
+
+std::unique_ptr<ComposerLayerResource> ComposerResources::createLayerResource(
+        uint32_t bufferCacheSize) {
+    return std::make_unique<ComposerLayerResource>(mImporter, bufferCacheSize);
+}
+
+ComposerDisplayResource* ComposerResources::findDisplayResourceLocked(Display display) {
+    auto iter = mDisplayResources.find(display);
+    if (iter == mDisplayResources.end()) {
+        return nullptr;
+    }
+    return iter->second.get();
+}
+
+Error ComposerResources::getHandle(Display display, Layer layer, uint32_t slot, Cache cache,
+                                   bool fromCache, const native_handle_t* rawHandle,
+                                   const native_handle_t** outHandle,
+                                   ReplacedHandle* outReplacedHandle) {
+    Error error;
+
+    // import the raw handle (or ignore raw handle when fromCache is true)
+    const native_handle_t* importedHandle = nullptr;
+    if (!fromCache) {
+        error = (outReplacedHandle->isBuffer())
+                        ? mImporter.importBuffer(rawHandle, &importedHandle)
+                        : mImporter.importStream(rawHandle, &importedHandle);
+        if (error != Error::NONE) {
+            return error;
+        }
+    }
+
+    std::lock_guard<std::mutex> lock(mDisplayResourcesMutex);
+
+    // find display/layer resource
+    const bool needLayerResource = (cache == ComposerResources::Cache::LAYER_BUFFER ||
+                                    cache == ComposerResources::Cache::LAYER_SIDEBAND_STREAM);
+    ComposerDisplayResource* displayResource = findDisplayResourceLocked(display);
+    ComposerLayerResource* layerResource = (displayResource && needLayerResource)
+                                                   ? displayResource->findLayerResource(layer)
+                                                   : nullptr;
+
+    // lookup or update cache
+    const native_handle_t* replacedHandle = nullptr;
+    if (displayResource && (!needLayerResource || layerResource)) {
+        switch (cache) {
+            case ComposerResources::Cache::CLIENT_TARGET:
+                error = displayResource->getClientTarget(slot, fromCache, importedHandle, outHandle,
+                                                         &replacedHandle);
+                break;
+            case ComposerResources::Cache::OUTPUT_BUFFER:
+                error = displayResource->getOutputBuffer(slot, fromCache, importedHandle, outHandle,
+                                                         &replacedHandle);
+                break;
+            case ComposerResources::Cache::LAYER_BUFFER:
+                error = layerResource->getBuffer(slot, fromCache, importedHandle, outHandle,
+                                                 &replacedHandle);
+                break;
+            case ComposerResources::Cache::LAYER_SIDEBAND_STREAM:
+                error = layerResource->getSidebandStream(slot, fromCache, importedHandle, outHandle,
+                                                         &replacedHandle);
+                break;
+            default:
+                error = Error::BAD_PARAMETER;
+                break;
+        }
+
+        if (error != Error::NONE) {
+            ALOGW("invalid cache %d slot %d", int(cache), int(slot));
+        }
+    } else if (!displayResource) {
+        error = Error::BAD_DISPLAY;
+    } else {
+        error = Error::BAD_LAYER;
+    }
+
+    // clean up on errors
+    if (error != Error::NONE) {
+        if (!fromCache) {
+            if (outReplacedHandle->isBuffer()) {
+                mImporter.freeBuffer(importedHandle);
+            } else {
+                mImporter.freeStream(importedHandle);
+            }
+        }
+        return error;
+    }
+
+    outReplacedHandle->reset(&mImporter, replacedHandle);
+
+    return Error::NONE;
+}
+
+}  // namespace hal
+}  // namespace V2_1
+}  // namespace composer
+}  // namespace graphics
+}  // namespace hardware
+}  // namespace android
diff --git a/graphics/composer/2.1/utils/resources/include/composer-resources/2.1/ComposerResources.h b/graphics/composer/2.1/utils/resources/include/composer-resources/2.1/ComposerResources.h
new file mode 100644
index 0000000..b9b7138
--- /dev/null
+++ b/graphics/composer/2.1/utils/resources/include/composer-resources/2.1/ComposerResources.h
@@ -0,0 +1,258 @@
+/*
+ * Copyright 2018 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#pragma once
+
+#ifndef LOG_TAG
+#warning "ComposerResources.h included without LOG_TAG"
+#endif
+
+#include <memory>
+#include <mutex>
+#include <unordered_map>
+#include <vector>
+
+#include <android/hardware/graphics/composer/2.1/types.h>
+
+#include <android/hardware/graphics/mapper/2.0/IMapper.h>
+#include <android/hardware/graphics/mapper/3.0/IMapper.h>
+#include <log/log.h>
+
+namespace android {
+namespace hardware {
+namespace graphics {
+namespace composer {
+namespace V2_1 {
+namespace hal {
+
+// wrapper for IMapper to import buffers and sideband streams
+class ComposerHandleImporter {
+  public:
+    bool init();
+
+    Error importBuffer(const native_handle_t* rawHandle, const native_handle_t** outBufferHandle);
+    void freeBuffer(const native_handle_t* bufferHandle);
+    Error importStream(const native_handle_t* rawHandle, const native_handle_t** outStreamHandle);
+    void freeStream(const native_handle_t* streamHandle);
+
+  private:
+    sp<mapper::V2_0::IMapper> mMapper2;
+    sp<mapper::V3_0::IMapper> mMapper3;
+};
+
+class ComposerHandleCache {
+  public:
+    enum class HandleType {
+        INVALID,
+        BUFFER,
+        STREAM,
+    };
+
+    ComposerHandleCache(ComposerHandleImporter& importer, HandleType type, uint32_t cacheSize);
+
+    // must be initialized later with initCache
+    ComposerHandleCache(ComposerHandleImporter& importer);
+
+    ~ComposerHandleCache();
+
+    ComposerHandleCache(const ComposerHandleCache&) = delete;
+    ComposerHandleCache& operator=(const ComposerHandleCache&) = delete;
+
+    bool initCache(HandleType type, uint32_t cacheSize);
+    Error lookupCache(uint32_t slot, const native_handle_t** outHandle);
+    Error updateCache(uint32_t slot, const native_handle_t* handle,
+                      const native_handle** outReplacedHandle);
+
+    // when fromCache is true, look up in the cache; otherwise, update the cache
+    Error getHandle(uint32_t slot, bool fromCache, const native_handle_t* inHandle,
+                    const native_handle_t** outHandle, const native_handle** outReplacedHandle);
+
+  private:
+    ComposerHandleImporter& mImporter;
+    HandleType mHandleType = HandleType::INVALID;
+    std::vector<const native_handle_t*> mHandles;
+};
+
+// layer resource
+class ComposerLayerResource {
+  public:
+    ComposerLayerResource(ComposerHandleImporter& importer, uint32_t bufferCacheSize);
+
+    virtual ~ComposerLayerResource() = default;
+
+    Error getBuffer(uint32_t slot, bool fromCache, const native_handle_t* inHandle,
+                    const native_handle_t** outHandle, const native_handle** outReplacedHandle);
+    Error getSidebandStream(uint32_t slot, bool fromCache, const native_handle_t* inHandle,
+                            const native_handle_t** outHandle,
+                            const native_handle** outReplacedHandle);
+
+  protected:
+    ComposerHandleCache mBufferCache;
+    ComposerHandleCache mSidebandStreamCache;
+};
+
+// display resource
+class ComposerDisplayResource {
+  public:
+    enum class DisplayType {
+        PHYSICAL,
+        VIRTUAL,
+    };
+
+    virtual ~ComposerDisplayResource() = default;
+
+    ComposerDisplayResource(DisplayType type, ComposerHandleImporter& importer,
+                            uint32_t outputBufferCacheSize);
+
+    bool initClientTargetCache(uint32_t cacheSize);
+
+    bool isVirtual() const;
+
+    Error getClientTarget(uint32_t slot, bool fromCache, const native_handle_t* inHandle,
+                          const native_handle_t** outHandle,
+                          const native_handle** outReplacedHandle);
+
+    Error getOutputBuffer(uint32_t slot, bool fromCache, const native_handle_t* inHandle,
+                          const native_handle_t** outHandle,
+                          const native_handle** outReplacedHandle);
+
+    bool addLayer(Layer layer, std::unique_ptr<ComposerLayerResource> layerResource);
+    bool removeLayer(Layer layer);
+    ComposerLayerResource* findLayerResource(Layer layer);
+    std::vector<Layer> getLayers() const;
+
+    void setMustValidateState(bool mustValidate);
+
+    bool mustValidate() const;
+
+  protected:
+    const DisplayType mType;
+    ComposerHandleCache mClientTargetCache;
+    ComposerHandleCache mOutputBufferCache;
+    bool mMustValidate;
+
+    std::unordered_map<Layer, std::unique_ptr<ComposerLayerResource>> mLayerResources;
+};
+
+class ComposerResources {
+  public:
+    static std::unique_ptr<ComposerResources> create();
+
+    ComposerResources() = default;
+    virtual ~ComposerResources() = default;
+
+    bool init();
+
+    using RemoveDisplay =
+            std::function<void(Display display, bool isVirtual, const std::vector<Layer>& layers)>;
+    void clear(RemoveDisplay removeDisplay);
+
+    Error addPhysicalDisplay(Display display);
+    Error addVirtualDisplay(Display display, uint32_t outputBufferCacheSize);
+
+    Error removeDisplay(Display display);
+
+    Error setDisplayClientTargetCacheSize(Display display, uint32_t clientTargetCacheSize);
+
+    Error addLayer(Display display, Layer layer, uint32_t bufferCacheSize);
+    Error removeLayer(Display display, Layer layer);
+
+    void setDisplayMustValidateState(Display display, bool mustValidate);
+
+    bool mustValidateDisplay(Display display);
+
+    // When a buffer in the cache is replaced by a new one, we must keep it
+    // alive until it has been replaced in ComposerHal.
+    class ReplacedHandle {
+      public:
+        explicit ReplacedHandle(bool isBuffer) : mIsBuffer(isBuffer) {}
+        ReplacedHandle(const ReplacedHandle&) = delete;
+        ReplacedHandle& operator=(const ReplacedHandle&) = delete;
+
+        ~ReplacedHandle() { reset(); }
+
+        bool isBuffer() { return mIsBuffer; }
+
+        void reset(ComposerHandleImporter* importer = nullptr,
+                   const native_handle_t* handle = nullptr) {
+            if (mHandle) {
+                if (mIsBuffer) {
+                    mImporter->freeBuffer(mHandle);
+                } else {
+                    mImporter->freeStream(mHandle);
+                }
+            }
+
+            mImporter = importer;
+            mHandle = handle;
+        }
+
+      private:
+        bool mIsBuffer;
+        ComposerHandleImporter* mImporter = nullptr;
+        const native_handle_t* mHandle = nullptr;
+    };
+
+    Error getDisplayClientTarget(Display display, uint32_t slot, bool fromCache,
+                                 const native_handle_t* rawHandle,
+                                 const native_handle_t** outBufferHandle,
+                                 ReplacedHandle* outReplacedBuffer);
+
+    Error getDisplayOutputBuffer(Display display, uint32_t slot, bool fromCache,
+                                 const native_handle_t* rawHandle,
+                                 const native_handle_t** outBufferHandle,
+                                 ReplacedHandle* outReplacedBuffer);
+
+    Error getLayerBuffer(Display display, Layer layer, uint32_t slot, bool fromCache,
+                         const native_handle_t* rawHandle, const native_handle_t** outBufferHandle,
+                         ReplacedHandle* outReplacedBuffer);
+
+    Error getLayerSidebandStream(Display display, Layer layer, const native_handle_t* rawHandle,
+                                 const native_handle_t** outStreamHandle,
+                                 ReplacedHandle* outReplacedStream);
+
+  protected:
+    virtual std::unique_ptr<ComposerDisplayResource> createDisplayResource(
+            ComposerDisplayResource::DisplayType type, uint32_t outputBufferCacheSize);
+
+    virtual std::unique_ptr<ComposerLayerResource> createLayerResource(uint32_t bufferCacheSize);
+
+    ComposerDisplayResource* findDisplayResourceLocked(Display display);
+
+    ComposerHandleImporter mImporter;
+
+    std::mutex mDisplayResourcesMutex;
+    std::unordered_map<Display, std::unique_ptr<ComposerDisplayResource>> mDisplayResources;
+
+  private:
+    enum class Cache {
+        CLIENT_TARGET,
+        OUTPUT_BUFFER,
+        LAYER_BUFFER,
+        LAYER_SIDEBAND_STREAM,
+    };
+
+    Error getHandle(Display display, Layer layer, uint32_t slot, Cache cache, bool fromCache,
+                    const native_handle_t* rawHandle, const native_handle_t** outHandle,
+                    ReplacedHandle* outReplacedHandle);
+};
+
+}  // namespace hal
+}  // namespace V2_1
+}  // namespace composer
+}  // namespace graphics
+}  // namespace hardware
+}  // namespace android