SF: Remove *DisplayId::tryCast usage from VirtualDisplaySurface

Work towards DisplayId opaqueness by eliminating call-sites to APIs that
parse the display ID values directly. One such site is
VirtualDisplaySurface.

Replace all calls to *DisplayId::tryCast with a VirtualDisplayIdVariant
guard.

Flag: com.android.graphics.surfaceflinger.flags.stable_edid_ids
Bug: 390690584
Test: libsurfaceflinger_unittest
Change-Id: I7ae9e838547c31ce09349e15f7d23e99f313646b
diff --git a/services/surfaceflinger/DisplayHardware/VirtualDisplaySurface.cpp b/services/surfaceflinger/DisplayHardware/VirtualDisplaySurface.cpp
index 384f7b2..56ed11f 100644
--- a/services/surfaceflinger/DisplayHardware/VirtualDisplaySurface.cpp
+++ b/services/surfaceflinger/DisplayHardware/VirtualDisplaySurface.cpp
@@ -47,7 +47,8 @@
 
 namespace android {
 
-VirtualDisplaySurface::VirtualDisplaySurface(HWComposer& hwc, VirtualDisplayId displayId,
+VirtualDisplaySurface::VirtualDisplaySurface(HWComposer& hwc,
+                                             VirtualDisplayIdVariant virtualIdVariant,
                                              const sp<IGraphicBufferProducer>& sink,
                                              const sp<IGraphicBufferProducer>& bqProducer,
                                              const sp<IGraphicBufferConsumer>& bqConsumer,
@@ -58,7 +59,7 @@
       : ConsumerBase(bqConsumer),
 #endif // COM_ANDROID_GRAPHICS_LIBGUI_FLAGS(WB_CONSUMER_BASE_OWNS_BQ)
         mHwc(hwc),
-        mDisplayId(displayId),
+        mVirtualIdVariant(virtualIdVariant),
         mDisplayName(name),
         mSource{},
         mDefaultOutputFormat(HAL_PIXEL_FORMAT_IMPLEMENTATION_DEFINED),
@@ -119,7 +120,7 @@
 }
 
 status_t VirtualDisplaySurface::beginFrame(bool mustRecompose) {
-    if (GpuVirtualDisplayId::tryCast(mDisplayId)) {
+    if (isBackedByGpu()) {
         return NO_ERROR;
     }
 
@@ -133,7 +134,7 @@
 }
 
 status_t VirtualDisplaySurface::prepareFrame(CompositionType compositionType) {
-    if (GpuVirtualDisplayId::tryCast(mDisplayId)) {
+    if (isBackedByGpu()) {
         return NO_ERROR;
     }
 
@@ -181,7 +182,10 @@
 }
 
 status_t VirtualDisplaySurface::advanceFrame(float hdrSdrRatio) {
-    if (GpuVirtualDisplayId::tryCast(mDisplayId)) {
+    const auto halVirtualDisplayId = ftl::match(
+            mVirtualIdVariant, [](HalVirtualDisplayId id) { return ftl::Optional(id); },
+            [](auto) { return ftl::Optional<HalVirtualDisplayId>(); });
+    if (!halVirtualDisplayId) {
         return NO_ERROR;
     }
 
@@ -212,11 +216,8 @@
     VDS_LOGV("%s: fb=%d(%p) out=%d(%p)", __func__, mFbProducerSlot, fbBuffer.get(),
              mOutputProducerSlot, outBuffer.get());
 
-    const auto halDisplayId = HalVirtualDisplayId::tryCast(mDisplayId);
-    LOG_FATAL_IF(!halDisplayId);
-    // At this point we know the output buffer acquire fence,
-    // so update HWC state with it.
-    mHwc.setOutputBuffer(*halDisplayId, mOutputFence, outBuffer);
+    // At this point we know the output buffer acquire fence, so update HWC state with it.
+    mHwc.setOutputBuffer(*halVirtualDisplayId, mOutputFence, outBuffer);
 
     status_t result = NO_ERROR;
     if (fbBuffer != nullptr) {
@@ -227,7 +228,7 @@
             hwcBuffer = fbBuffer; // HWC hasn't previously seen this buffer in this slot
         }
         // TODO: Correctly propagate the dataspace from GL composition
-        result = mHwc.setClientTarget(*halDisplayId, mFbProducerSlot, mFbFence, hwcBuffer,
+        result = mHwc.setClientTarget(*halVirtualDisplayId, mFbProducerSlot, mFbFence, hwcBuffer,
                                       ui::Dataspace::UNKNOWN, hdrSdrRatio);
     }
 
@@ -235,8 +236,8 @@
 }
 
 void VirtualDisplaySurface::onFrameCommitted() {
-    const auto halDisplayId = HalVirtualDisplayId::tryCast(mDisplayId);
-    if (!halDisplayId) {
+    const auto halDisplayId = asHalDisplayId(mVirtualIdVariant);
+    if (!halDisplayId.has_value()) {
         return;
     }
 
@@ -250,8 +251,7 @@
         Mutex::Autolock lock(mMutex);
         int sslot = mapProducer2SourceSlot(SOURCE_SCRATCH, mFbProducerSlot);
         VDS_LOGV("%s: release scratch sslot=%d", __func__, sslot);
-        addReleaseFenceLocked(sslot, mProducerBuffers[mFbProducerSlot],
-                retireFence);
+        addReleaseFenceLocked(sslot, mProducerBuffers[mFbProducerSlot], retireFence);
         releaseBufferLocked(sslot, mProducerBuffers[mFbProducerSlot]);
     }
 
@@ -299,7 +299,7 @@
 
 status_t VirtualDisplaySurface::requestBuffer(int pslot,
         sp<GraphicBuffer>* outBuf) {
-    if (GpuVirtualDisplayId::tryCast(mDisplayId)) {
+    if (isBackedByGpu()) {
         return mSource[SOURCE_SINK]->requestBuffer(pslot, outBuf);
     }
 
@@ -321,7 +321,7 @@
 
 status_t VirtualDisplaySurface::dequeueBuffer(Source source,
         PixelFormat format, uint64_t usage, int* sslot, sp<Fence>* fence) {
-    LOG_ALWAYS_FATAL_IF(GpuVirtualDisplayId::tryCast(mDisplayId).has_value());
+    LOG_ALWAYS_FATAL_IF(isBackedByGpu());
 
     status_t result =
             mSource[source]->dequeueBuffer(sslot, fence, mSinkBufferWidth, mSinkBufferHeight,
@@ -373,7 +373,7 @@
                                               PixelFormat format, uint64_t usage,
                                               uint64_t* outBufferAge,
                                               FrameEventHistoryDelta* outTimestamps) {
-    if (GpuVirtualDisplayId::tryCast(mDisplayId)) {
+    if (isBackedByGpu()) {
         return mSource[SOURCE_SINK]->dequeueBuffer(pslot, fence, w, h, format, usage, outBufferAge,
                                                    outTimestamps);
     }
@@ -459,7 +459,7 @@
 
 status_t VirtualDisplaySurface::queueBuffer(int pslot,
         const QueueBufferInput& input, QueueBufferOutput* output) {
-    if (GpuVirtualDisplayId::tryCast(mDisplayId)) {
+    if (isBackedByGpu()) {
         return mSource[SOURCE_SINK]->queueBuffer(pslot, input, output);
     }
 
@@ -517,7 +517,7 @@
 
 status_t VirtualDisplaySurface::cancelBuffer(int pslot,
         const sp<Fence>& fence) {
-    if (GpuVirtualDisplayId::tryCast(mDisplayId)) {
+    if (isBackedByGpu()) {
         return mSource[SOURCE_SINK]->cancelBuffer(mapProducer2SourceSlot(SOURCE_SINK, pslot), fence);
     }
 
@@ -621,7 +621,10 @@
 }
 
 status_t VirtualDisplaySurface::refreshOutputBuffer() {
-    LOG_ALWAYS_FATAL_IF(GpuVirtualDisplayId::tryCast(mDisplayId).has_value());
+    const auto halVirtualDisplayId = ftl::match(
+            mVirtualIdVariant, [](HalVirtualDisplayId id) { return ftl::Optional(id); },
+            [](auto) { return ftl::Optional<HalVirtualDisplayId>(); });
+    LOG_ALWAYS_FATAL_IF(!halVirtualDisplayId);
 
     if (mOutputProducerSlot >= 0) {
         mSource[SOURCE_SINK]->cancelBuffer(
@@ -640,14 +643,16 @@
     // until after GPU calls queueBuffer(). So here we just set the buffer
     // (for use in HWC prepare) but not the fence; we'll call this again with
     // the proper fence once we have it.
-    const auto halDisplayId = HalVirtualDisplayId::tryCast(mDisplayId);
-    LOG_FATAL_IF(!halDisplayId);
-    result = mHwc.setOutputBuffer(*halDisplayId, Fence::NO_FENCE,
+    result = mHwc.setOutputBuffer(*halVirtualDisplayId, Fence::NO_FENCE,
                                   mProducerBuffers[mOutputProducerSlot]);
 
     return result;
 }
 
+bool VirtualDisplaySurface::isBackedByGpu() const {
+    return std::holds_alternative<GpuVirtualDisplayId>(mVirtualIdVariant);
+}
+
 // This slot mapping function is its own inverse, so two copies are unnecessary.
 // Both are kept to make the intent clear where the function is called, and for
 // the (unlikely) chance that we switch to a different mapping function.
diff --git a/services/surfaceflinger/DisplayHardware/VirtualDisplaySurface.h b/services/surfaceflinger/DisplayHardware/VirtualDisplaySurface.h
index 90426f7..cb65c79 100644
--- a/services/surfaceflinger/DisplayHardware/VirtualDisplaySurface.h
+++ b/services/surfaceflinger/DisplayHardware/VirtualDisplaySurface.h
@@ -75,7 +75,8 @@
                               public BnGraphicBufferProducer,
                               private ConsumerBase {
 public:
-    VirtualDisplaySurface(HWComposer&, VirtualDisplayId, const sp<IGraphicBufferProducer>& sink,
+    VirtualDisplaySurface(HWComposer&, VirtualDisplayIdVariant,
+                          const sp<IGraphicBufferProducer>& sink,
                           const sp<IGraphicBufferProducer>& bqProducer,
                           const sp<IGraphicBufferConsumer>& bqConsumer, const std::string& name);
 
@@ -145,6 +146,7 @@
     void updateQueueBufferOutput(QueueBufferOutput&&);
     void resetPerFrameState();
     status_t refreshOutputBuffer();
+    bool isBackedByGpu() const;
 
     // Both the sink and scratch buffer pools have their own set of slots
     // ("source slots", or "sslot"). We have to merge these into the single
@@ -159,7 +161,7 @@
     // Immutable after construction
     //
     HWComposer& mHwc;
-    const VirtualDisplayId mDisplayId;
+    const VirtualDisplayIdVariant mVirtualIdVariant;
     const std::string mDisplayName;
     sp<IGraphicBufferProducer> mSource[2]; // indexed by SOURCE_*
     uint32_t mDefaultOutputFormat;
diff --git a/services/surfaceflinger/SurfaceFlinger.cpp b/services/surfaceflinger/SurfaceFlinger.cpp
index ab468c9..d6b51ae 100644
--- a/services/surfaceflinger/SurfaceFlinger.cpp
+++ b/services/surfaceflinger/SurfaceFlinger.cpp
@@ -659,15 +659,15 @@
     }
 }
 
-void SurfaceFlinger::acquireVirtualDisplay(ui::Size resolution, ui::PixelFormat format,
-                                           const std::string& uniqueId,
-                                           compositionengine::DisplayCreationArgsBuilder& builder) {
+std::optional<VirtualDisplayIdVariant> SurfaceFlinger::acquireVirtualDisplay(
+        ui::Size resolution, ui::PixelFormat format, const std::string& uniqueId,
+        compositionengine::DisplayCreationArgsBuilder& builder) {
     if (auto& generator = mVirtualDisplayIdGenerators.hal) {
         if (const auto id = generator->generateId()) {
             if (getHwComposer().allocateVirtualDisplay(*id, resolution, &format)) {
                 acquireVirtualDisplaySnapshot(*id, uniqueId);
                 builder.setId(*id);
-                return;
+                return *id;
             }
 
             generator->releaseId(*id);
@@ -682,6 +682,7 @@
     LOG_ALWAYS_FATAL_IF(!id, "Failed to generate ID for GPU virtual display");
     acquireVirtualDisplaySnapshot(*id, uniqueId);
     builder.setId(*id);
+    return *id;
 }
 
 void SurfaceFlinger::releaseVirtualDisplay(VirtualDisplayId displayId) {
@@ -4007,10 +4008,12 @@
     }
 
     compositionengine::DisplayCreationArgsBuilder builder;
+    std::optional<VirtualDisplayIdVariant> virtualDisplayIdVariantOpt;
     if (const auto& physical = state.physical) {
         builder.setId(physical->id);
     } else {
-        acquireVirtualDisplay(resolution, pixelFormat, state.uniqueId, builder);
+        virtualDisplayIdVariantOpt =
+                acquireVirtualDisplay(resolution, pixelFormat, state.uniqueId, builder);
     }
 
     builder.setPixels(resolution);
@@ -4030,10 +4033,10 @@
     getFactory().createBufferQueue(&bqProducer, &bqConsumer, /*consumerIsSurfaceFlinger =*/false);
 
     if (state.isVirtual()) {
-        const auto displayId = VirtualDisplayId::tryCast(compositionDisplay->getId());
-        LOG_FATAL_IF(!displayId);
-        auto surface = sp<VirtualDisplaySurface>::make(getHwComposer(), *displayId, state.surface,
-                                                       bqProducer, bqConsumer, state.displayName);
+        LOG_FATAL_IF(!virtualDisplayIdVariantOpt);
+        auto surface = sp<VirtualDisplaySurface>::make(getHwComposer(), *virtualDisplayIdVariantOpt,
+                                                       state.surface, bqProducer, bqConsumer,
+                                                       state.displayName);
         displaySurface = surface;
         producer = std::move(surface);
     } else {
diff --git a/services/surfaceflinger/SurfaceFlinger.h b/services/surfaceflinger/SurfaceFlinger.h
index 2d81738..1114aff 100644
--- a/services/surfaceflinger/SurfaceFlinger.h
+++ b/services/surfaceflinger/SurfaceFlinger.h
@@ -1126,8 +1126,10 @@
     void enableHalVirtualDisplays(bool);
 
     // Virtual display lifecycle for ID generation and HAL allocation.
-    void acquireVirtualDisplay(ui::Size, ui::PixelFormat, const std::string& uniqueId,
-                               compositionengine::DisplayCreationArgsBuilder&) REQUIRES(mStateLock);
+    std::optional<VirtualDisplayIdVariant> acquireVirtualDisplay(
+            ui::Size, ui::PixelFormat, const std::string& uniqueId,
+            compositionengine::DisplayCreationArgsBuilder&) REQUIRES(mStateLock);
+
     template <typename ID>
     void acquireVirtualDisplaySnapshot(ID displayId, const std::string& uniqueId) {
         std::lock_guard lock(mVirtualDisplaysMutex);