libgui: Add unlimited slot support to Surfaces and Consumers

Surfaces can now use `setMaxDequeuedBufferCount` with any value when the
consumer supports it to give themselves an essentially unlimited number
of buffers to use.

ConsumerBase and its libgui children have been updated to allow for
unlimited buffer slots by default (meaning all users opt into this
automatically), and their implementations have been updated to track the
new variable slot limit.

This is part of go/warren-buffers.

Bug: 341359185
Flag: com.android.graphics.libgui.flags.wb_unlimited_slots
Test: new tests, old tests
Change-Id: I374aa204a2e42a17d95c6e0ffaef2c2caaa9c963

13 files changed, 469 insertions, 43 deletions

diff --git a/libs/gui/ConsumerBase.cpp b/libs/gui/ConsumerBase.cpp
index e772f44a4f..504509dbec 100644
--- a/libs/gui/ConsumerBase.cpp
+++ b/libs/gui/ConsumerBase.cpp
@@ -37,6 +37,8 @@
 
 #include <private/gui/ComposerService.h>
 
+#include <ui/BufferQueueDefs.h>
+
 #include <log/log.h>
 #include <utils/Log.h>
 #include <utils/String8.h>
@@ -59,7 +61,11 @@ static int32_t createProcessUniqueId() {
     return android_atomic_inc(&globalCounter);
 }
 
-ConsumerBase::ConsumerBase(const sp<IGraphicBufferConsumer>& bufferQueue, bool controlledByApp) :
+ConsumerBase::ConsumerBase(const sp<IGraphicBufferConsumer>& bufferQueue, bool controlledByApp)
+      :
+#if COM_ANDROID_GRAPHICS_LIBGUI_FLAGS(WB_UNLIMITED_SLOTS)
+        mSlots(BufferQueueDefs::NUM_BUFFER_SLOTS),
+#endif
         mAbandoned(false),
         mConsumer(bufferQueue),
         mPrevFinalReleaseFence(Fence::NO_FENCE) {
@@ -68,7 +74,12 @@ ConsumerBase::ConsumerBase(const sp<IGraphicBufferConsumer>& bufferQueue, bool c
 
 #if COM_ANDROID_GRAPHICS_LIBGUI_FLAGS(WB_CONSUMER_BASE_OWNS_BQ)
 ConsumerBase::ConsumerBase(bool controlledByApp, bool consumerIsSurfaceFlinger)
-      : mAbandoned(false), mPrevFinalReleaseFence(Fence::NO_FENCE) {
+      :
+#if COM_ANDROID_GRAPHICS_LIBGUI_FLAGS(WB_UNLIMITED_SLOTS)
+        mSlots(BufferQueueDefs::NUM_BUFFER_SLOTS),
+#endif
+        mAbandoned(false),
+        mPrevFinalReleaseFence(Fence::NO_FENCE) {
     sp<IGraphicBufferProducer> producer;
     BufferQueue::createBufferQueue(&producer, &mConsumer, consumerIsSurfaceFlinger);
     mSurface = sp<Surface>::make(producer, controlledByApp);
@@ -77,7 +88,11 @@ ConsumerBase::ConsumerBase(bool controlledByApp, bool consumerIsSurfaceFlinger)
 
 ConsumerBase::ConsumerBase(const sp<IGraphicBufferProducer>& producer,
                            const sp<IGraphicBufferConsumer>& consumer, bool controlledByApp)
-      : mAbandoned(false),
+      :
+#if COM_ANDROID_GRAPHICS_LIBGUI_FLAGS(WB_UNLIMITED_SLOTS)
+        mSlots(BufferQueueDefs::NUM_BUFFER_SLOTS),
+#endif
+        mAbandoned(false),
         mConsumer(consumer),
         mSurface(sp<Surface>::make(producer, controlledByApp)),
         mPrevFinalReleaseFence(Fence::NO_FENCE) {
@@ -101,9 +116,16 @@ void ConsumerBase::initialize(bool controlledByApp) {
     if (err != NO_ERROR) {
         CB_LOGE("ConsumerBase: error connecting to BufferQueue: %s (%d)",
                 strerror(-err), err);
-    } else {
-        mConsumer->setConsumerName(mName);
+        return;
     }
+
+    mConsumer->setConsumerName(mName);
+#if COM_ANDROID_GRAPHICS_LIBGUI_FLAGS(WB_UNLIMITED_SLOTS)
+    if (err = mConsumer->allowUnlimitedSlots(true); err != NO_ERROR) {
+        CB_LOGE("ConsumerBase: error marking as allowed to have unlimited slots: %s (%d)",
+                strerror(-err), err);
+    }
+#endif
 }
 
 ConsumerBase::~ConsumerBase() {
@@ -130,7 +152,11 @@ int ConsumerBase::getSlotForBufferLocked(const sp<GraphicBuffer>& buffer) {
     }
 
     uint64_t id = buffer->getId();
-    for (int i = 0; i < BufferQueueDefs::NUM_BUFFER_SLOTS; i++) {
+#if COM_ANDROID_GRAPHICS_LIBGUI_FLAGS(WB_UNLIMITED_SLOTS)
+    for (int i = 0; i < (int)mSlots.size(); ++i) {
+#else
+    for (int i = 0; i < BufferQueue::NUM_BUFFER_SLOTS; i++) {
+#endif
         auto& slot = mSlots[i];
         if (slot.mGraphicBuffer && slot.mGraphicBuffer->getId() == id) {
             return i;
@@ -242,6 +268,15 @@ void ConsumerBase::onBuffersReleased() {
         return;
     }
 
+#if COM_ANDROID_GRAPHICS_LIBGUI_FLAGS(WB_UNLIMITED_SLOTS)
+    std::vector<bool> mask;
+    mConsumer->getReleasedBuffersExtended(&mask);
+    for (size_t i = 0; i < mSlots.size(); i++) {
+        if (mask[i]) {
+            freeBufferLocked(i);
+        }
+    }
+#else
     uint64_t mask = 0;
     mConsumer->getReleasedBuffers(&mask);
     for (int i = 0; i < BufferQueue::NUM_BUFFER_SLOTS; i++) {
@@ -249,6 +284,7 @@ void ConsumerBase::onBuffersReleased() {
             freeBufferLocked(i);
         }
     }
+#endif
 }
 
 void ConsumerBase::onSidebandStreamChanged() {
@@ -281,7 +317,11 @@ void ConsumerBase::abandonLocked() {
         CB_LOGE("abandonLocked: ConsumerBase is abandoned!");
         return;
     }
+#if COM_ANDROID_GRAPHICS_LIBGUI_FLAGS(WB_UNLIMITED_SLOTS)
+    for (int i = 0; i < (int)mSlots.size(); ++i) {
+#else
     for (int i =0; i < BufferQueue::NUM_BUFFER_SLOTS; i++) {
+#endif
         freeBufferLocked(i);
     }
     // disconnect from the BufferQueue
@@ -398,6 +438,15 @@ status_t ConsumerBase::setMaxBufferCount(int bufferCount) {
         CB_LOGE("setMaxBufferCount: ConsumerBase is abandoned!");
         return NO_INIT;
     }
+
+#if COM_ANDROID_GRAPHICS_LIBGUI_FLAGS(WB_UNLIMITED_SLOTS)
+    if (status_t err = mConsumer->allowUnlimitedSlots(false); err != NO_ERROR) {
+        CB_LOGE("ConsumerBase: error marking as not allowed to have unlimited slots: %s (%d)",
+                strerror(-err), err);
+        return err;
+    }
+#endif
+
     return mConsumer->setMaxBufferCount(bufferCount);
 }
 #endif // COM_ANDROID_GRAPHICS_LIBGUI_FLAGS(WB_CONSUMER_BASE_OWNS_BQ)
@@ -459,6 +508,15 @@ status_t ConsumerBase::discardFreeBuffers() {
     if (err != OK) {
         return err;
     }
+#if COM_ANDROID_GRAPHICS_LIBGUI_FLAGS(WB_UNLIMITED_SLOTS)
+    std::vector<bool> mask;
+    mConsumer->getReleasedBuffersExtended(&mask);
+    for (int i = 0; i < (int)mSlots.size(); i++) {
+        if (mask[i]) {
+            freeBufferLocked(i);
+        }
+    }
+#else
     uint64_t mask;
     mConsumer->getReleasedBuffers(&mask);
     for (int i = 0; i < BufferQueue::NUM_BUFFER_SLOTS; i++) {
@@ -466,6 +524,8 @@ status_t ConsumerBase::discardFreeBuffers() {
             freeBufferLocked(i);
         }
     }
+#endif
+
     return OK;
 }
 
@@ -607,6 +667,9 @@ status_t ConsumerBase::releaseBufferLocked(
     // buffer on the same slot), the buffer producer is definitely no longer
     // tracking it.
     if (!stillTracking(slot, graphicBuffer)) {
+        CB_LOGV("releaseBufferLocked: Not tracking, exiting without calling releaseBuffer for "
+                "slot=%d/%" PRIu64,
+                slot, mSlots[slot].mFrameNumber);
         return OK;
     }
 
@@ -626,7 +689,11 @@ status_t ConsumerBase::releaseBufferLocked(
 
 bool ConsumerBase::stillTracking(int slot,
         const sp<GraphicBuffer> graphicBuffer) {
+#if COM_ANDROID_GRAPHICS_LIBGUI_FLAGS(WB_UNLIMITED_SLOTS)
+    if (slot < 0 || slot >= (int)mSlots.size()) {
+#else
     if (slot < 0 || slot >= BufferQueue::NUM_BUFFER_SLOTS) {
+#endif
         return false;
     }
     return (mSlots[slot].mGraphicBuffer != nullptr &&
diff --git a/libs/gui/GLConsumer.cpp b/libs/gui/GLConsumer.cpp
index f2173cd740..168129b1f7 100644
--- a/libs/gui/GLConsumer.cpp
+++ b/libs/gui/GLConsumer.cpp
@@ -119,6 +119,9 @@ GLConsumer::GLConsumer(uint32_t tex, uint32_t texTarget, bool useFenceSync, bool
         mTexTarget(texTarget),
         mEglDisplay(EGL_NO_DISPLAY),
         mEglContext(EGL_NO_CONTEXT),
+#if COM_ANDROID_GRAPHICS_LIBGUI_FLAGS(WB_UNLIMITED_SLOTS)
+        mEglSlots(BufferQueueDefs::NUM_BUFFER_SLOTS),
+#endif
         mCurrentTexture(BufferQueue::INVALID_BUFFER_SLOT),
         mAttached(true) {
     GLC_LOGV("GLConsumer");
@@ -129,27 +132,29 @@ GLConsumer::GLConsumer(uint32_t tex, uint32_t texTarget, bool useFenceSync, bool
 }
 #endif // COM_ANDROID_GRAPHICS_LIBGUI_FLAGS(WB_CONSUMER_BASE_OWNS_BQ)
 
-GLConsumer::GLConsumer(const sp<IGraphicBufferConsumer>& bq, uint32_t tex,
-        uint32_t texTarget, bool useFenceSync, bool isControlledByApp) :
-    ConsumerBase(bq, isControlledByApp),
-    mCurrentCrop(Rect::EMPTY_RECT),
-    mCurrentTransform(0),
-    mCurrentScalingMode(NATIVE_WINDOW_SCALING_MODE_FREEZE),
-    mCurrentFence(Fence::NO_FENCE),
-    mCurrentTimestamp(0),
-    mCurrentDataSpace(HAL_DATASPACE_UNKNOWN),
-    mCurrentFrameNumber(0),
-    mDefaultWidth(1),
-    mDefaultHeight(1),
-    mFilteringEnabled(true),
-    mTexName(tex),
-    mUseFenceSync(useFenceSync),
-    mTexTarget(texTarget),
-    mEglDisplay(EGL_NO_DISPLAY),
-    mEglContext(EGL_NO_CONTEXT),
-    mCurrentTexture(BufferQueue::INVALID_BUFFER_SLOT),
-    mAttached(true)
-{
+GLConsumer::GLConsumer(const sp<IGraphicBufferConsumer>& bq, uint32_t tex, uint32_t texTarget,
+                       bool useFenceSync, bool isControlledByApp)
+      : ConsumerBase(bq, isControlledByApp),
+        mCurrentCrop(Rect::EMPTY_RECT),
+        mCurrentTransform(0),
+        mCurrentScalingMode(NATIVE_WINDOW_SCALING_MODE_FREEZE),
+        mCurrentFence(Fence::NO_FENCE),
+        mCurrentTimestamp(0),
+        mCurrentDataSpace(HAL_DATASPACE_UNKNOWN),
+        mCurrentFrameNumber(0),
+        mDefaultWidth(1),
+        mDefaultHeight(1),
+        mFilteringEnabled(true),
+        mTexName(tex),
+        mUseFenceSync(useFenceSync),
+        mTexTarget(texTarget),
+        mEglDisplay(EGL_NO_DISPLAY),
+        mEglContext(EGL_NO_CONTEXT),
+#if COM_ANDROID_GRAPHICS_LIBGUI_FLAGS(WB_UNLIMITED_SLOTS)
+        mEglSlots(BufferQueueDefs::NUM_BUFFER_SLOTS),
+#endif
+        mCurrentTexture(BufferQueue::INVALID_BUFFER_SLOT),
+        mAttached(true) {
     GLC_LOGV("GLConsumer");
 
     memcpy(mCurrentTransformMatrix, mtxIdentity.asArray(),
@@ -176,6 +181,9 @@ GLConsumer::GLConsumer(uint32_t texTarget, bool useFenceSync, bool isControlledB
         mTexTarget(texTarget),
         mEglDisplay(EGL_NO_DISPLAY),
         mEglContext(EGL_NO_CONTEXT),
+#if COM_ANDROID_GRAPHICS_LIBGUI_FLAGS(WB_UNLIMITED_SLOTS)
+        mEglSlots(BufferQueueDefs::NUM_BUFFER_SLOTS),
+#endif
         mCurrentTexture(BufferQueue::INVALID_BUFFER_SLOT),
         mAttached(false) {
     GLC_LOGV("GLConsumer");
@@ -204,6 +212,9 @@ GLConsumer::GLConsumer(const sp<IGraphicBufferConsumer>& bq, uint32_t texTarget,
         mTexTarget(texTarget),
         mEglDisplay(EGL_NO_DISPLAY),
         mEglContext(EGL_NO_CONTEXT),
+#if COM_ANDROID_GRAPHICS_LIBGUI_FLAGS(WB_UNLIMITED_SLOTS)
+        mEglSlots(BufferQueueDefs::NUM_BUFFER_SLOTS),
+#endif
         mCurrentTexture(BufferQueue::INVALID_BUFFER_SLOT),
         mAttached(false) {
     GLC_LOGV("GLConsumer");
@@ -395,6 +406,17 @@ status_t GLConsumer::acquireBufferLocked(BufferItem *item,
     return NO_ERROR;
 }
 
+#if COM_ANDROID_GRAPHICS_LIBGUI_FLAGS(WB_UNLIMITED_SLOTS)
+void GLConsumer::onSlotCountChanged(int slotCount) {
+    ConsumerBase::onSlotCountChanged(slotCount);
+
+    Mutex::Autolock lock(mMutex);
+    if (slotCount > (int)mEglSlots.size()) {
+        mEglSlots.resize(slotCount);
+    }
+}
+#endif
+
 status_t GLConsumer::releaseBufferLocked(int buf,
         sp<GraphicBuffer> graphicBuffer,
         EGLDisplay display, EGLSyncKHR eglFence) {
diff --git a/libs/gui/IGraphicBufferProducerFlattenables.cpp b/libs/gui/IGraphicBufferProducerFlattenables.cpp
index 4e92a39973..8b2e2ddc59 100644
--- a/libs/gui/IGraphicBufferProducerFlattenables.cpp
+++ b/libs/gui/IGraphicBufferProducerFlattenables.cpp
@@ -128,7 +128,7 @@ status_t IGraphicBufferProducer::QueueBufferInput::unflatten(
 constexpr size_t IGraphicBufferProducer::QueueBufferOutput::minFlattenedSize() {
     return sizeof(width) + sizeof(height) + sizeof(transformHint) + sizeof(numPendingBuffers) +
             sizeof(nextFrameNumber) + sizeof(bufferReplaced) + sizeof(maxBufferCount) +
-            sizeof(result);
+            sizeof(result) + sizeof(isSlotExpansionAllowed);
 }
 size_t IGraphicBufferProducer::QueueBufferOutput::getFlattenedSize() const {
     return minFlattenedSize() + frameTimestamps.getFlattenedSize();
@@ -152,6 +152,7 @@ status_t IGraphicBufferProducer::QueueBufferOutput::flatten(
     FlattenableUtils::write(buffer, size, nextFrameNumber);
     FlattenableUtils::write(buffer, size, bufferReplaced);
     FlattenableUtils::write(buffer, size, maxBufferCount);
+    FlattenableUtils::write(buffer, size, isSlotExpansionAllowed);
 
     status_t result = frameTimestamps.flatten(buffer, size, fds, count);
     if (result != NO_ERROR) {
@@ -175,6 +176,7 @@ status_t IGraphicBufferProducer::QueueBufferOutput::unflatten(
     FlattenableUtils::read(buffer, size, nextFrameNumber);
     FlattenableUtils::read(buffer, size, bufferReplaced);
     FlattenableUtils::read(buffer, size, maxBufferCount);
+    FlattenableUtils::read(buffer, size, isSlotExpansionAllowed);
 
     status_t result = frameTimestamps.unflatten(buffer, size, fds, count);
     if (result != NO_ERROR) {
diff --git a/libs/gui/Surface.cpp b/libs/gui/Surface.cpp
index e41f9bbf43..ec23365e1f 100644
--- a/libs/gui/Surface.cpp
+++ b/libs/gui/Surface.cpp
@@ -38,6 +38,7 @@
 #include <utils/NativeHandle.h>
 #include <utils/Trace.h>
 
+#include <ui/BufferQueueDefs.h>
 #include <ui/DynamicDisplayInfo.h>
 #include <ui/Fence.h>
 #include <ui/GraphicBuffer.h>
@@ -98,7 +99,10 @@ Surface::Surface(const sp<IGraphicBufferProducer>& bufferProducer, bool controll
       : mGraphicBufferProducer(bufferProducer),
 #if COM_ANDROID_GRAPHICS_LIBGUI_FLAGS(WB_PLATFORM_API_IMPROVEMENTS)
         mSurfaceDeathListener(nullptr),
-#endif // COM_ANDROID_GRAPHICS_LIBGUI_FLAGS(WB_PLATFORM_API_IMPROVEMENTS)
+#endif
+#if COM_ANDROID_GRAPHICS_LIBGUI_FLAGS(WB_UNLIMITED_SLOTS)
+        mSlots(NUM_BUFFER_SLOTS),
+#endif
         mCrop(Rect::EMPTY_RECT),
         mBufferAge(0),
         mGenerationNumber(0),
@@ -192,7 +196,7 @@ void Surface::allocateBuffers() {
 status_t Surface::allowAllocation(bool allowAllocation) {
     return mGraphicBufferProducer->allowAllocation(allowAllocation);
 }
-#endif // COM_ANDROID_GRAPHICS_LIBGUI_FLAGS(WB_PLATFORM_API_IMPROVEMENTS)
+#endif
 
 status_t Surface::setGenerationNumber(uint32_t generation) {
     status_t result = mGraphicBufferProducer->setGenerationNumber(generation);
@@ -658,7 +662,11 @@ int Surface::dequeueBuffer(android_native_buffer_t** buffer, int* fenceFd) {
         return result;
     }
 
+#if COM_ANDROID_GRAPHICS_LIBGUI_FLAGS(WB_UNLIMITED_SLOTS)
+    if (buf < 0 || buf >= (int)mSlots.size()) {
+#else
     if (buf < 0 || buf >= NUM_BUFFER_SLOTS) {
+#endif
         ALOGE("dequeueBuffer: IGraphicBufferProducer returned invalid slot number %d", buf);
         android_errorWriteLog(0x534e4554, "36991414"); // SafetyNet logging
         return FAILED_TRANSACTION;
@@ -757,7 +765,11 @@ status_t Surface::detachBuffer(const sp<GraphicBuffer>& buffer) {
     Mutex::Autolock lock(mMutex);
 
     uint64_t bufferId = buffer->getId();
+#if COM_ANDROID_GRAPHICS_LIBGUI_FLAGS(WB_UNLIMITED_SLOTS)
+    for (int slot = 0; slot < (int)mSlots.size(); ++slot) {
+#else
     for (int slot = 0; slot < Surface::NUM_BUFFER_SLOTS; ++slot) {
+#endif
         auto& bufferSlot = mSlots[slot];
         if (bufferSlot.buffer != nullptr && bufferSlot.buffer->getId() == bufferId) {
             bufferSlot.buffer = nullptr;
@@ -840,7 +852,11 @@ int Surface::dequeueBuffers(std::vector<BatchBuffer>* buffers) {
             return output.result;
         }
 
+#if COM_ANDROID_GRAPHICS_LIBGUI_FLAGS(WB_UNLIMITED_SLOTS)
+        if (output.slot < 0 || output.slot >= (int)mSlots.size()) {
+#else
         if (output.slot < 0 || output.slot >= NUM_BUFFER_SLOTS) {
+#endif
             mGraphicBufferProducer->cancelBuffers(cancelBufferInputs, &cancelBufferOutputs);
             ALOGE("%s: IGraphicBufferProducer returned invalid slot number %d",
                     __FUNCTION__, output.slot);
@@ -1027,7 +1043,11 @@ int Surface::getSlotFromBufferLocked(
         return BAD_VALUE;
     }
 
+#if COM_ANDROID_GRAPHICS_LIBGUI_FLAGS(WB_UNLIMITED_SLOTS)
+    for (int i = 0; i < (int)mSlots.size(); i++) {
+#else
     for (int i = 0; i < NUM_BUFFER_SLOTS; i++) {
+#endif
         if (mSlots[i].buffer != nullptr &&
                 mSlots[i].buffer->handle == buffer->handle) {
             return i;
@@ -2094,6 +2114,9 @@ int Surface::connect(int api, const sp<SurfaceListener>& listener, bool reportBu
         mDefaultHeight = output.height;
         mNextFrameNumber = output.nextFrameNumber;
         mMaxBufferCount = output.maxBufferCount;
+#if COM_ANDROID_GRAPHICS_LIBGUI_FLAGS(WB_UNLIMITED_SLOTS)
+        mIsSlotExpansionAllowed = output.isSlotExpansionAllowed;
+#endif
 
         // Ignore transform hint if sticky transform is set or transform to display inverse flag is
         // set. Transform hint should be ignored if the client is expected to always submit buffers
@@ -2190,7 +2213,11 @@ int Surface::detachNextBuffer(sp<GraphicBuffer>* outBuffer,
         *outFence = Fence::NO_FENCE;
     }
 
+#if COM_ANDROID_GRAPHICS_LIBGUI_FLAGS(WB_UNLIMITED_SLOTS)
+    for (int i = 0; i < (int)mSlots.size(); i++) {
+#else
     for (int i = 0; i < NUM_BUFFER_SLOTS; i++) {
+#endif
         if (mSlots[i].buffer != nullptr &&
                 mSlots[i].buffer->getId() == buffer->getId()) {
             if (mReportRemovedBuffers) {
@@ -2292,8 +2319,35 @@ int Surface::setMaxDequeuedBufferCount(int maxDequeuedBuffers) {
     ALOGV("Surface::setMaxDequeuedBufferCount");
     Mutex::Autolock lock(mMutex);
 
-    status_t err = mGraphicBufferProducer->setMaxDequeuedBufferCount(
-            maxDequeuedBuffers);
+#if COM_ANDROID_GRAPHICS_LIBGUI_FLAGS(WB_UNLIMITED_SLOTS)
+    if (maxDequeuedBuffers > BufferQueueDefs::NUM_BUFFER_SLOTS && !mIsSlotExpansionAllowed) {
+        return BAD_VALUE;
+    }
+
+    int minUndequeuedBuffers = 0;
+    status_t err = mGraphicBufferProducer->query(NATIVE_WINDOW_MIN_UNDEQUEUED_BUFFERS,
+                                                 &minUndequeuedBuffers);
+    if (err != OK) {
+        ALOGE("IGraphicBufferProducer::query(NATIVE_WINDOW_MIN_UNDEQUEUED_BUFFERS) returned %s",
+              strerror(-err));
+        return err;
+    }
+
+    if (maxDequeuedBuffers > (int)mSlots.size()) {
+        int newSlotCount = minUndequeuedBuffers + maxDequeuedBuffers;
+        err = mGraphicBufferProducer->extendSlotCount(newSlotCount);
+        if (err != OK) {
+            ALOGE("IGraphicBufferProducer::extendSlotCount(%d) returned %s", newSlotCount,
+                  strerror(-err));
+            return err;
+        }
+
+        mSlots.resize(newSlotCount);
+    }
+    err = mGraphicBufferProducer->setMaxDequeuedBufferCount(maxDequeuedBuffers);
+#else
+    status_t err = mGraphicBufferProducer->setMaxDequeuedBufferCount(maxDequeuedBuffers);
+#endif
     ALOGE_IF(err, "IGraphicBufferProducer::setMaxDequeuedBufferCount(%d) "
             "returned %s", maxDequeuedBuffers, strerror(-err));
 
@@ -2501,7 +2555,11 @@ void Surface::freeAllBuffers() {
         ALOGE("%s: %zu buffers were freed while being dequeued!",
                 __FUNCTION__, mDequeuedSlots.size());
     }
+#if COM_ANDROID_GRAPHICS_LIBGUI_FLAGS(WB_UNLIMITED_SLOTS)
+    for (int i = 0; i < (int)mSlots.size(); i++) {
+#else
     for (int i = 0; i < NUM_BUFFER_SLOTS; i++) {
+#endif
         mSlots[i].buffer = nullptr;
     }
 }
@@ -2510,7 +2568,11 @@ status_t Surface::getAndFlushBuffersFromSlots(const std::vector<int32_t>& slots,
         std::vector<sp<GraphicBuffer>>* outBuffers) {
     ALOGV("Surface::getAndFlushBuffersFromSlots");
     for (int32_t i : slots) {
+#if COM_ANDROID_GRAPHICS_LIBGUI_FLAGS(WB_UNLIMITED_SLOTS)
+        if (i < 0 || i >= (int)mSlots.size()) {
+#else
         if (i < 0 || i >= NUM_BUFFER_SLOTS) {
+#endif
             ALOGE("%s: Invalid slotIndex: %d", __FUNCTION__, i);
             return BAD_VALUE;
         }
@@ -2670,7 +2732,11 @@ status_t Surface::lock(
             newDirtyRegion.set(bounds);
             mDirtyRegion.clear();
             Mutex::Autolock lock(mMutex);
-            for (size_t i=0 ; i<NUM_BUFFER_SLOTS ; i++) {
+#if COM_ANDROID_GRAPHICS_LIBGUI_FLAGS(WB_UNLIMITED_SLOTS)
+            for (int i = 0; i < (int)mSlots.size(); i++) {
+#else
+            for (int i = 0; i < NUM_BUFFER_SLOTS; i++) {
+#endif
                 mSlots[i].dirtyRegion.clear();
             }
         }
diff --git a/libs/gui/include/gui/GLConsumer.h b/libs/gui/include/gui/GLConsumer.h
index 8a66dc0cf1..30cbfa2f9f 100644
--- a/libs/gui/include/gui/GLConsumer.h
+++ b/libs/gui/include/gui/GLConsumer.h
@@ -266,6 +266,9 @@ protected:
     virtual status_t acquireBufferLocked(BufferItem *item, nsecs_t presentWhen,
             uint64_t maxFrameNumber = 0) override;
 
+#if COM_ANDROID_GRAPHICS_LIBGUI_FLAGS(WB_UNLIMITED_SLOTS)
+    virtual void onSlotCountChanged(int slotCount) override;
+#endif
     // releaseBufferLocked overrides the ConsumerBase method to update the
     // mEglSlots array in addition to the ConsumerBase.
     virtual status_t releaseBufferLocked(int slot, const sp<GraphicBuffer> graphicBuffer,
@@ -496,8 +499,11 @@ private:
     // slot that has not yet been used. The buffer allocated to a slot will also
     // be replaced if the requested buffer usage or geometry differs from that
     // of the buffer allocated to a slot.
+#if COM_ANDROID_GRAPHICS_LIBGUI_FLAGS(WB_UNLIMITED_SLOTS)
+    std::vector<EglSlot> mEglSlots;
+#else
     EglSlot mEglSlots[BufferQueueDefs::NUM_BUFFER_SLOTS];
-
+#endif
     // mCurrentTexture is the buffer slot index of the buffer that is currently
     // bound to the OpenGL texture. It is initialized to INVALID_BUFFER_SLOT,
     // indicating that no buffer slot is currently bound to the texture. Note,
diff --git a/libs/gui/include/gui/Surface.h b/libs/gui/include/gui/Surface.h
index 14a351316d..755674d9e6 100644
--- a/libs/gui/include/gui/Surface.h
+++ b/libs/gui/include/gui/Surface.h
@@ -558,7 +558,11 @@ protected:
     // slot that has not yet been used. The buffer allocated to a slot will also
     // be replaced if the requested buffer usage or geometry differs from that
     // of the buffer allocated to a slot.
+#if COM_ANDROID_GRAPHICS_LIBGUI_FLAGS(WB_UNLIMITED_SLOTS)
+    std::vector<BufferSlot> mSlots;
+#else
     BufferSlot mSlots[NUM_BUFFER_SLOTS];
+#endif
 
     // mReqWidth is the buffer width that will be requested at the next dequeue
     // operation. It is initialized to 1.
@@ -732,6 +736,10 @@ protected:
     std::vector<sp<GraphicBuffer>> mRemovedBuffers;
     int mMaxBufferCount;
 
+#if COM_ANDROID_GRAPHICS_LIBGUI_FLAGS(WB_UNLIMITED_SLOTS)
+    bool mIsSlotExpansionAllowed;
+#endif
+
     sp<IProducerListener> mListenerProxy;
 
     // Get and flush the buffers of given slots, if the buffer in the slot
diff --git a/libs/gui/tests/BufferItemConsumer_test.cpp b/libs/gui/tests/BufferItemConsumer_test.cpp
index 3b6a66efe9..6453885804 100644
--- a/libs/gui/tests/BufferItemConsumer_test.cpp
+++ b/libs/gui/tests/BufferItemConsumer_test.cpp
@@ -22,8 +22,11 @@
 #include <gui/BufferItemConsumer.h>
 #include <gui/IProducerListener.h>
 #include <gui/Surface.h>
+#include <ui/BufferQueueDefs.h>
 #include <ui/GraphicBuffer.h>
 
+#include <unordered_set>
+
 namespace android {
 
 static constexpr int kWidth = 100;
@@ -57,6 +60,8 @@ class BufferItemConsumerTest : public ::testing::Test {
     };
 
     void SetUp() override {
+        mBuffers.resize(BufferQueueDefs::NUM_BUFFER_SLOTS);
+
         mBIC = new BufferItemConsumer(kUsage, kMaxLockedBuffers, true);
         String8 name("BufferItemConsumer_Under_Test");
         mBIC->setName(name);
@@ -137,6 +142,11 @@ class BufferItemConsumerTest : public ::testing::Test {
         ASSERT_EQ(NO_ERROR, ret);
     }
 
+    void DetachBuffer(int slot) {
+        ALOGD("detachBuffer: slot=%d", slot);
+        status_t ret = mBIC->detachBuffer(mBuffers[slot]);
+        ASSERT_EQ(NO_ERROR, ret);
+    }
 
     std::mutex mMutex;
     int mFreedBufferCount{0};
@@ -146,7 +156,7 @@ class BufferItemConsumerTest : public ::testing::Test {
     sp<BufferFreedListener> mBFL;
     sp<IGraphicBufferProducer> mProducer;
     sp<IGraphicBufferConsumer> mConsumer;
-    sp<GraphicBuffer> mBuffers[BufferQueueDefs::NUM_BUFFER_SLOTS];
+    std::vector<sp<GraphicBuffer>> mBuffers;
 };
 
 // Test that detaching buffer from consumer side triggers onBufferFreed.
@@ -239,4 +249,52 @@ TEST_F(BufferItemConsumerTest, DetachBufferWithBuffer) {
 }
 #endif // COM_ANDROID_GRAPHICS_LIBGUI_FLAGS(WB_PLATFORM_API_IMPROVEMENTS)
 
+#if COM_ANDROID_GRAPHICS_LIBGUI_FLAGS(WB_UNLIMITED_SLOTS)
+TEST_F(BufferItemConsumerTest, UnlimitedSlots_AcquireReleaseAll) {
+    ASSERT_EQ(OK, mProducer->extendSlotCount(256));
+    mBuffers.resize(256);
+
+    ASSERT_EQ(OK, mProducer->setMaxDequeuedBufferCount(100));
+
+    std::unordered_set<int> slots;
+    for (int i = 0; i < 100; i++) {
+        int slot;
+        DequeueBuffer(&slot);
+        slots.insert(slot);
+    }
+    EXPECT_EQ(100u, slots.size());
+
+    for (int dequeuedSlot : slots) {
+        QueueBuffer(dequeuedSlot);
+
+        int slot;
+        AcquireBuffer(&slot);
+        ReleaseBuffer(slot);
+    }
+}
+
+TEST_F(BufferItemConsumerTest, UnlimitedSlots_AcquireDetachAll) {
+    ASSERT_EQ(OK, mProducer->extendSlotCount(256));
+    mBuffers.resize(256);
+
+    ASSERT_EQ(OK, mProducer->setMaxDequeuedBufferCount(100));
+
+    std::unordered_set<int> slots;
+    for (int i = 0; i < 100; i++) {
+        int slot;
+        DequeueBuffer(&slot);
+        slots.insert(slot);
+    }
+    EXPECT_EQ(100u, slots.size());
+
+    for (int dequeuedSlot : slots) {
+        QueueBuffer(dequeuedSlot);
+
+        int slot;
+        AcquireBuffer(&slot);
+        DetachBuffer(slot);
+    }
+}
+#endif
+
 }  // namespace android
diff --git a/libs/gui/tests/BufferQueue_test.cpp b/libs/gui/tests/BufferQueue_test.cpp
index 6138306dbe..77b4ae8623 100644
--- a/libs/gui/tests/BufferQueue_test.cpp
+++ b/libs/gui/tests/BufferQueue_test.cpp
@@ -1669,7 +1669,9 @@ protected:
     void setUpConsumer() {
         EXPECT_EQ(OK, mConsumer->consumerConnect(mConsumerListener, false));
 
+#if COM_ANDROID_GRAPHICS_LIBGUI_FLAGS(WB_UNLIMITED_SLOTS)
         EXPECT_EQ(OK, mConsumer->allowUnlimitedSlots(true));
+#endif
         EXPECT_EQ(OK, mConsumer->setConsumerUsageBits(GraphicBuffer::USAGE_SW_READ_OFTEN));
         EXPECT_EQ(OK, mConsumer->setDefaultBufferSize(10, 10));
         EXPECT_EQ(OK, mConsumer->setDefaultBufferFormat(PIXEL_FORMAT_RGBA_8888));
@@ -1683,7 +1685,9 @@ protected:
         EXPECT_EQ(OK,
                   mProducer->connect(mProducerListener, NATIVE_WINDOW_API_CPU,
                                      /*producerControlledByApp*/ true, &output));
-
+#if COM_ANDROID_GRAPHICS_LIBGUI_FLAGS(WB_UNLIMITED_SLOTS)
+        ASSERT_TRUE(output.isSlotExpansionAllowed);
+#endif
         ASSERT_EQ(OK, mProducer->setMaxDequeuedBufferCount(kDequeableBufferCount));
         ASSERT_EQ(OK, mProducer->allowAllocation(true));
     }
diff --git a/libs/gui/tests/CpuConsumer_test.cpp b/libs/gui/tests/CpuConsumer_test.cpp
index f4239cb69e..9476930de3 100644
--- a/libs/gui/tests/CpuConsumer_test.cpp
+++ b/libs/gui/tests/CpuConsumer_test.cpp
@@ -803,6 +803,27 @@ INSTANTIATE_TEST_CASE_P(Rgba8888Tests,
         ::testing::ValuesIn(rgba8888TestSets));
 #endif
 
-
-
+#if COM_ANDROID_GRAPHICS_LIBGUI_FLAGS(WB_UNLIMITED_SLOTS)
+TEST(CpuConsumerSlotTest, UnlimitedSlots_AcquireReleaseAll) {
+    sp<CpuConsumer> cpuConsumer = sp<CpuConsumer>::make(3);
+    sp<Surface> surface = cpuConsumer->getSurface();
+    sp<SurfaceListener> listener = sp<StubSurfaceListener>::make();
+
+    ASSERT_EQ(OK, surface->connect(NATIVE_WINDOW_API_CPU, listener));
+    ASSERT_EQ(OK, surface->setMaxDequeuedBufferCount(256));
+
+    std::vector<Surface::BatchBuffer> buffers(256);
+    EXPECT_EQ(OK, surface->dequeueBuffers(&buffers));
+
+    for (auto& buffer : buffers) {
+        sp<GraphicBuffer> graphicBuffer = GraphicBuffer::from(buffer.buffer);
+        sp<Fence> fence = sp<Fence>::make(buffer.fenceFd);
+        EXPECT_EQ(OK, surface->queueBuffer(graphicBuffer, fence));
+
+        CpuConsumer::LockedBuffer nativeBuffer;
+        EXPECT_EQ(OK, cpuConsumer->lockNextBuffer(&nativeBuffer));
+        EXPECT_EQ(OK, cpuConsumer->unlockBuffer(nativeBuffer));
+    }
+}
+#endif
 } // namespace android
diff --git a/libs/gui/tests/FillBuffer.cpp b/libs/gui/tests/FillBuffer.cpp
index b60995a624..11383d906b 100644
--- a/libs/gui/tests/FillBuffer.cpp
+++ b/libs/gui/tests/FillBuffer.cpp
@@ -76,7 +76,7 @@ void fillYV12BufferRect(uint8_t* buf, int w, int h, int stride,
 }
 
 void fillRGBA8Buffer(uint8_t* buf, int w, int h, int stride) {
-    const size_t PIXEL_SIZE = 4;
+    constexpr size_t PIXEL_SIZE = 4;
     for (int x = 0; x < w; x++) {
         for (int y = 0; y < h; y++) {
             off_t offset = (y * stride + x) * PIXEL_SIZE;
@@ -89,6 +89,21 @@ void fillRGBA8Buffer(uint8_t* buf, int w, int h, int stride) {
     }
 }
 
+void fillRGBA8Buffer(uint8_t* buf, int w, int h, int stride, uint8_t r, uint8_t g, uint8_t b,
+                     uint8_t a) {
+    constexpr size_t PIXEL_SIZE = 4;
+
+    for (int x = 0; x < w; x++) {
+        for (int y = 0; y < h; y++) {
+            off_t offset = (y * stride + x) * PIXEL_SIZE;
+            buf[offset] = r;
+            buf[offset + 1] = g;
+            buf[offset + 2] = b;
+            buf[offset + 3] = a;
+        }
+    }
+}
+
 void produceOneRGBA8Frame(const sp<ANativeWindow>& anw) {
     android_native_buffer_t* anb;
     ASSERT_EQ(NO_ERROR, native_window_dequeue_buffer_and_wait(anw.get(),
diff --git a/libs/gui/tests/FillBuffer.h b/libs/gui/tests/FillBuffer.h
index b584179318..f5d6b8bbda 100644
--- a/libs/gui/tests/FillBuffer.h
+++ b/libs/gui/tests/FillBuffer.h
@@ -30,6 +30,8 @@ void fillYV12BufferRect(uint8_t* buf, int w, int h, int stride,
         const android_native_rect_t& rect);
 
 void fillRGBA8Buffer(uint8_t* buf, int w, int h, int stride);
+void fillRGBA8Buffer(uint8_t* buf, int w, int h, int stride, uint8_t r, uint8_t g, uint8_t b,
+                     uint8_t a);
 
 // Produce a single RGBA8 frame by filling a buffer with a checkerboard pattern
 // using the CPU.  This assumes that the ANativeWindow is already configured to
diff --git a/libs/gui/tests/SurfaceTextureGL_test.cpp b/libs/gui/tests/SurfaceTextureGL_test.cpp
index 449533aa57..b22b85332c 100644
--- a/libs/gui/tests/SurfaceTextureGL_test.cpp
+++ b/libs/gui/tests/SurfaceTextureGL_test.cpp
@@ -17,6 +17,8 @@
 #define LOG_TAG "SurfaceTextureGL_test"
 //#define LOG_NDEBUG 0
 
+#include <gmock/gmock.h>
+
 #include "SurfaceTextureGL.h"
 
 #include "DisconnectWaiter.h"
@@ -735,4 +737,30 @@ TEST_F(SurfaceTextureGLTest, InvalidWidthOrHeightFails) {
     ASSERT_NE(NO_ERROR, mST->updateTexImage());
 }
 
+#if COM_ANDROID_GRAPHICS_LIBGUI_FLAGS(WB_CONSUMER_BASE_OWNS_BQ)
+TEST_F(SurfaceTextureGLTest, TestUnlimitedSlots) {
+    ASSERT_EQ(OK, mSTC->connect(NATIVE_WINDOW_API_CPU, sp<StubSurfaceListener>::make()));
+    ASSERT_EQ(OK, mSTC->setMaxDequeuedBufferCount(256));
+
+    std::vector<Surface::BatchBuffer> buffers(256);
+    ASSERT_EQ(OK, mSTC->dequeueBuffers(&buffers));
+    ASSERT_EQ(256u, buffers.size());
+    ASSERT_THAT(buffers, Each(Field(&Surface::BatchBuffer::buffer, ::testing::NotNull())));
+
+    for (size_t i = 0; i < buffers.size(); ++i) {
+        sp<GraphicBuffer> graphicBuffer = GraphicBuffer::from(buffers[i].buffer);
+        sp<Fence> fence = sp<Fence>::make(buffers[i].fenceFd);
+
+        void* buf;
+        ASSERT_EQ(OK, graphicBuffer->lock(AHARDWAREBUFFER_USAGE_CPU_WRITE_OFTEN, &buf));
+        fillRGBA8Buffer((uint8_t*)buf, graphicBuffer->getWidth(), graphicBuffer->getHeight(),
+                        graphicBuffer->getStride(), i, i, i, i);
+        graphicBuffer->unlock();
+
+        ASSERT_EQ(OK, mSTC->queueBuffer(graphicBuffer, fence));
+        ASSERT_EQ(OK, mST->updateTexImage());
+        checkPixel(0, 0, i, i, i, i);
+    }
+}
+#endif
 } // namespace android
diff --git a/libs/gui/tests/Surface_test.cpp b/libs/gui/tests/Surface_test.cpp
index 76362ff272..e771d6db7f 100644
--- a/libs/gui/tests/Surface_test.cpp
+++ b/libs/gui/tests/Surface_test.cpp
@@ -14,10 +14,6 @@
  * limitations under the License.
  */
 
-#include "gui/view/Surface.h"
-#include "Constants.h"
-#include "MockConsumer.h"
-
 #include <gtest/gtest.h>
 
 #include <SurfaceFlingerProperties.h>
@@ -36,10 +32,13 @@
 #include <gui/IConsumerListener.h>
 #include <gui/IGraphicBufferConsumer.h>
 #include <gui/IGraphicBufferProducer.h>
+#include <gui/IProducerListener.h>
 #include <gui/ISurfaceComposer.h>
 #include <gui/Surface.h>
 #include <gui/SurfaceComposerClient.h>
 #include <gui/SyncScreenCaptureListener.h>
+#include <gui/view/Surface.h>
+#include <nativebase/nativebase.h>
 #include <private/gui/ComposerService.h>
 #include <private/gui/ComposerServiceAIDL.h>
 #include <sys/types.h>
@@ -47,6 +46,7 @@
 #include <ui/BufferQueueDefs.h>
 #include <ui/DisplayMode.h>
 #include <ui/GraphicBuffer.h>
+#include <ui/PixelFormat.h>
 #include <ui/Rect.h>
 #include <utils/Errors.h>
 #include <utils/String8.h>
@@ -55,9 +55,12 @@
 #include <cstddef>
 #include <cstdint>
 #include <future>
+#include <iterator>
 #include <limits>
 #include <thread>
 
+#include "Constants.h"
+#include "MockConsumer.h"
 #include "testserver/TestServerClient.h"
 
 namespace android {
@@ -2529,4 +2532,128 @@ TEST_F(SurfaceTest, QueueBufferOutput_TracksReplacements_Plural) {
 }
 #endif // COM_ANDROID_GRAPHICS_LIBGUI_FLAGS(WB_PLATFORM_API_IMPROVEMENTS)
 
+#if COM_ANDROID_GRAPHICS_LIBGUI_FLAGS(WB_UNLIMITED_SLOTS)
+TEST_F(SurfaceTest, UnlimitedSlots_FailsOnIncompatibleConsumer) {
+    sp<IGraphicBufferProducer> producer;
+    sp<IGraphicBufferConsumer> consumer;
+    BufferQueue::createBufferQueue(&producer, &consumer);
+
+    sp<IConsumerListener> consumerListener = sp<FakeConsumer>::make();
+
+    EXPECT_EQ(OK, consumer->allowUnlimitedSlots(false));
+    EXPECT_EQ(OK, consumer->consumerConnect(consumerListener, /* consumerListener */ true));
+
+    sp<Surface> surface = sp<Surface>::make(producer);
+    sp<SurfaceListener> surfaceListener = sp<StubSurfaceListener>::make();
+    EXPECT_EQ(OK, surface->connect(NATIVE_WINDOW_API_CPU, surfaceListener));
+
+    EXPECT_NE(OK, surface->setMaxDequeuedBufferCount(128))
+            << "We shouldn't be able to set high max buffer counts if the consumer doesn't allow "
+               "it";
+}
+
+TEST_F(SurfaceTest, UnlimitedSlots_CanDequeueAndQueueMoreThanOldMaximum) {
+    sp<IGraphicBufferProducer> producer;
+    sp<IGraphicBufferConsumer> consumer;
+    BufferQueue::createBufferQueue(&producer, &consumer);
+
+    sp<IConsumerListener> consumerListener = sp<FakeConsumer>::make();
+
+    EXPECT_EQ(OK, consumer->allowUnlimitedSlots(true));
+    EXPECT_EQ(OK, consumer->consumerConnect(consumerListener, /* consumerListener */ true));
+    EXPECT_EQ(OK, consumer->setDefaultBufferFormat(PIXEL_FORMAT_RGBA_8888));
+    EXPECT_EQ(OK, consumer->setConsumerUsageBits(AHARDWAREBUFFER_USAGE_CPU_WRITE_OFTEN));
+
+    sp<Surface> surface = sp<Surface>::make(producer);
+    sp<SurfaceListener> surfaceListener = sp<StubSurfaceListener>::make();
+    EXPECT_EQ(OK, surface->connect(NATIVE_WINDOW_API_CPU, surfaceListener));
+
+    EXPECT_EQ(OK, surface->setMaxDequeuedBufferCount(128))
+            << "If unlimited slots are allowed, we should be able increase the max dequeued buffer "
+               "count arbitrarily";
+
+    std::vector<std::tuple<sp<GraphicBuffer>, sp<Fence>, int>> buffers;
+    for (int i = 0; i < 128; i++) {
+        sp<GraphicBuffer> buffer;
+        sp<Fence> fence;
+        ASSERT_EQ(OK, surface->dequeueBuffer(&buffer, &fence)) << "Unable to dequeue buffer #" << i;
+        buffers.push_back({buffer, fence, i});
+    }
+
+    for (auto& [buffer, fence, idx] : buffers) {
+        ASSERT_EQ(OK, surface->queueBuffer(buffer, fence)) << "Unable to queue buffer #" << idx;
+    }
+}
+
+TEST_F(SurfaceTest, UnlimitedSlots_CanDequeueAndDetachMoreThanOldMaximum) {
+    sp<IGraphicBufferProducer> producer;
+    sp<IGraphicBufferConsumer> consumer;
+    BufferQueue::createBufferQueue(&producer, &consumer);
+
+    sp<IConsumerListener> consumerListener = sp<FakeConsumer>::make();
+
+    EXPECT_EQ(OK, consumer->allowUnlimitedSlots(true));
+    EXPECT_EQ(OK, consumer->consumerConnect(consumerListener, /* consumerListener */ true));
+    EXPECT_EQ(OK, consumer->setDefaultBufferFormat(PIXEL_FORMAT_RGBA_8888));
+    EXPECT_EQ(OK, consumer->setConsumerUsageBits(AHARDWAREBUFFER_USAGE_CPU_WRITE_OFTEN));
+
+    sp<Surface> surface = sp<Surface>::make(producer);
+    sp<SurfaceListener> surfaceListener = sp<StubSurfaceListener>::make();
+    EXPECT_EQ(OK, surface->connect(NATIVE_WINDOW_API_CPU, surfaceListener));
+
+    EXPECT_EQ(OK, surface->setMaxDequeuedBufferCount(128))
+            << "If unlimited slots are allowed, we should be able increase the max dequeued buffer "
+               "count arbitrarily";
+
+    std::vector<std::tuple<sp<GraphicBuffer>, sp<Fence>, int>> buffers;
+    for (int i = 0; i < 128; i++) {
+        sp<GraphicBuffer> buffer;
+        sp<Fence> fence;
+        ASSERT_EQ(OK, surface->dequeueBuffer(&buffer, &fence)) << "Unable to dequeue buffer #" << i;
+        buffers.push_back({buffer, fence, i});
+    }
+
+    for (auto& [buffer, _, idx] : buffers) {
+        ASSERT_EQ(OK, surface->detachBuffer(buffer)) << "Unable to detach buffer #" << idx;
+    }
+}
+
+TEST_F(SurfaceTest, UnlimitedSlots_BatchOperations) {
+    sp<IGraphicBufferProducer> producer;
+    sp<IGraphicBufferConsumer> consumer;
+    BufferQueue::createBufferQueue(&producer, &consumer);
+
+    sp<IConsumerListener> consumerListener = sp<FakeConsumer>::make();
+
+    EXPECT_EQ(OK, consumer->allowUnlimitedSlots(true));
+    EXPECT_EQ(OK, consumer->consumerConnect(consumerListener, /* consumerListener */ true));
+    EXPECT_EQ(OK, consumer->setDefaultBufferFormat(PIXEL_FORMAT_RGBA_8888));
+    EXPECT_EQ(OK, consumer->setConsumerUsageBits(AHARDWAREBUFFER_USAGE_CPU_WRITE_OFTEN));
+
+    sp<Surface> surface = sp<Surface>::make(producer);
+    sp<SurfaceListener> surfaceListener = sp<StubSurfaceListener>::make();
+    EXPECT_EQ(OK, surface->connect(NATIVE_WINDOW_API_CPU, surfaceListener));
+
+    EXPECT_EQ(OK, surface->setMaxDequeuedBufferCount(128))
+            << "If unlimited slots are allowed, we should be able increase the max dequeued buffer "
+               "count arbitrarily";
+
+    std::vector<Surface::BatchBuffer> buffers(128);
+    EXPECT_EQ(OK, surface->dequeueBuffers(&buffers));
+    EXPECT_EQ(128u, buffers.size());
+
+    std::vector<Surface::BatchQueuedBuffer> queuedBuffers;
+    std::transform(buffers.begin(), buffers.end(), std::back_inserter(queuedBuffers),
+                   [](Surface::BatchBuffer& buffer) {
+                       Surface::BatchQueuedBuffer out;
+                       out.buffer = buffer.buffer;
+                       out.fenceFd = buffer.fenceFd;
+                       return out;
+                   });
+
+    std::vector<SurfaceQueueBufferOutput> outputs;
+    EXPECT_EQ(OK, surface->queueBuffers(queuedBuffers, &outputs));
+    EXPECT_EQ(128u, outputs.size());
+}
+#endif // COM_ANDROID_GRAPHICS_LIBGUI_FLAGS(WB_UNLIMITED_SLOTS)
 } // namespace android