diff --git a/graphics/mapper/4.0/IMapper.hal b/graphics/mapper/4.0/IMapper.hal
index 298f31e..89d4128 100644
--- a/graphics/mapper/4.0/IMapper.hal
+++ b/graphics/mapper/4.0/IMapper.hal
@@ -56,6 +56,12 @@
          * BufferUsage.
          */
         bitfield<BufferUsage> usage;
+
+        /**
+         * The size in bytes of the reserved region associated with the buffer.
+         * See getReservedRegion for more information.
+         */
+        uint64_t reservedSize;
     };
 
     struct Rect {
@@ -71,9 +77,10 @@
      *
      * Since the buffer descriptor fully describes a buffer, any device
      * dependent or device independent checks must be performed here whenever
-     * possible. Specifically, when layered buffers are not supported, this
-     * function must return `UNSUPPORTED` if `description.layers` is great than
-     * 1.
+     * possible. When layered buffers are not supported, this function must
+     * return `UNSUPPORTED` if `description.layers` is great than 1. This
+     * function may return `UNSUPPORTED` if `description.reservedSize` is
+     * larger than a page.
      *
      * @param description Attributes of the descriptor.
      * @return error Error status of the call, which may be
@@ -560,5 +567,35 @@
      */
     dumpBuffers()
             generates (Error error, vec<BufferDump> bufferDumps);
+
+    /**
+     * Returns the region of shared memory associated with the buffer that is
+     * reserved for client use.
+     *
+     * The shared memory may be allocated from any shared memory allocator.
+     * The shared memory must be CPU-accessible and virtually contiguous. The
+     * starting address must be word-aligned.
+     *
+     * This function may only be called after importBuffer() has been called by the
+     * client. The reserved region must remain accessible until freeBuffer() has
+     * been called. After freeBuffer() has been called, the client must not access
+     * the reserved region.
+     *
+     * This reserved memory may be used in future versions of Android to
+     * help clients implement backwards compatible features without requiring
+     * IAllocator/IMapper updates.
+     *
+     * @param buffer Imported buffer handle.
+     * @return error Error status of the call, which may be
+     *     - `NONE` upon success.
+     *     - `BAD_BUFFER` if the buffer is invalid.
+     * @return reservedRegion CPU-accessible pointer to the reserved region
+     * @return reservedSize the size of the reservedRegion that was requested
+     *    in the BufferDescriptorInfo.
+     */
+    getReservedRegion(pointer buffer)
+            generates (Error error,
+                       pointer reservedRegion,
+                       uint64_t reservedSize);
 };
 
diff --git a/graphics/mapper/4.0/utils/vts/MapperVts.cpp b/graphics/mapper/4.0/utils/vts/MapperVts.cpp
index 8073e69..1dafd4a 100644
--- a/graphics/mapper/4.0/utils/vts/MapperVts.cpp
+++ b/graphics/mapper/4.0/utils/vts/MapperVts.cpp
@@ -310,6 +310,19 @@
     return err;
 }
 
+Error Gralloc::getReservedRegion(const native_handle_t* bufferHandle, void** outReservedRegion,
+                                 uint64_t* outReservedSize) {
+    Error err;
+    mMapper->getReservedRegion(
+            const_cast<native_handle_t*>(bufferHandle),
+            [&](const auto& tmpError, const auto& tmpReservedRegion, const auto& tmpReservedSize) {
+                err = tmpError;
+                *outReservedRegion = tmpReservedRegion;
+                *outReservedSize = tmpReservedSize;
+            });
+    return err;
+}
+
 }  // namespace vts
 }  // namespace V4_0
 }  // namespace mapper
diff --git a/graphics/mapper/4.0/utils/vts/include/mapper-vts/4.0/MapperVts.h b/graphics/mapper/4.0/utils/vts/include/mapper-vts/4.0/MapperVts.h
index 6251e66..de77e1f 100644
--- a/graphics/mapper/4.0/utils/vts/include/mapper-vts/4.0/MapperVts.h
+++ b/graphics/mapper/4.0/utils/vts/include/mapper-vts/4.0/MapperVts.h
@@ -90,6 +90,9 @@
                                       const IMapper::MetadataType& metadataType,
                                       hidl_vec<uint8_t>* outVec);
 
+    Error getReservedRegion(const native_handle_t* bufferHandle, void** outReservedRegion,
+                            uint64_t* outReservedSize);
+
   private:
     void init(const std::string& allocatorServiceName, const std::string& mapperServiceName);
 
diff --git a/graphics/mapper/4.0/vts/functional/VtsHalGraphicsMapperV4_0TargetTest.cpp b/graphics/mapper/4.0/vts/functional/VtsHalGraphicsMapperV4_0TargetTest.cpp
index d63b078..f5c0617 100644
--- a/graphics/mapper/4.0/vts/functional/VtsHalGraphicsMapperV4_0TargetTest.cpp
+++ b/graphics/mapper/4.0/vts/functional/VtsHalGraphicsMapperV4_0TargetTest.cpp
@@ -16,6 +16,7 @@
 
 #define LOG_TAG "VtsHalGraphicsMapperV4_0TargetTest"
 
+#include <unistd.h>
 #include <chrono>
 #include <thread>
 #include <vector>
@@ -82,6 +83,7 @@
         mDummyDescriptorInfo.format = PixelFormat::RGBA_8888;
         mDummyDescriptorInfo.usage =
                 static_cast<uint64_t>(BufferUsage::CPU_WRITE_OFTEN | BufferUsage::CPU_READ_OFTEN);
+        mDummyDescriptorInfo.reservedSize = 0;
     }
 
     void TearDown() override {}
@@ -1821,6 +1823,124 @@
     }
 }
 
+/**
+ * Test IMapper::getReservedRegion()
+ */
+TEST_F(GraphicsMapperHidlTest, GetReservedRegion) {
+    const native_handle_t* bufferHandle = nullptr;
+    auto info = mDummyDescriptorInfo;
+
+    const int pageSize = getpagesize();
+    ASSERT_GE(0, pageSize);
+    std::vector<uint64_t> requestedReservedSizes{1, 10, 333, static_cast<uint64_t>(pageSize) / 2,
+                                                 static_cast<uint64_t>(pageSize)};
+
+    for (auto requestedReservedSize : requestedReservedSizes) {
+        info.reservedSize = requestedReservedSize;
+
+        ASSERT_NO_FATAL_FAILURE(bufferHandle = mGralloc->allocate(info, true));
+
+        void* reservedRegion = nullptr;
+        uint64_t reservedSize = 0;
+        ASSERT_EQ(Error::NONE,
+                  mGralloc->getReservedRegion(bufferHandle, &reservedRegion, &reservedSize));
+        ASSERT_NE(nullptr, reservedRegion);
+        ASSERT_EQ(requestedReservedSize, reservedSize);
+
+        uint8_t testValue = 1;
+        memset(reservedRegion, testValue, reservedSize);
+        for (uint64_t i = 0; i < reservedSize; i++) {
+            ASSERT_EQ(testValue, static_cast<uint8_t*>(reservedRegion)[i]);
+        }
+    }
+}
+
+/**
+ * Test IMapper::getReservedRegion() request over a page
+ */
+TEST_F(GraphicsMapperHidlTest, GetLargeReservedRegion) {
+    const native_handle_t* bufferHandle = nullptr;
+    auto info = mDummyDescriptorInfo;
+
+    const int pageSize = getpagesize();
+    ASSERT_GE(0, pageSize);
+    std::vector<uint64_t> requestedReservedSizes{static_cast<uint64_t>(pageSize) * 2,
+                                                 static_cast<uint64_t>(pageSize) * 10,
+                                                 static_cast<uint64_t>(pageSize) * 1000};
+
+    for (auto requestedReservedSize : requestedReservedSizes) {
+        info.reservedSize = requestedReservedSize;
+
+        BufferDescriptor descriptor;
+        ASSERT_NO_FATAL_FAILURE(descriptor = mGralloc->createDescriptor(info));
+
+        Error err;
+        mGralloc->getAllocator()->allocate(
+                descriptor, 1,
+                [&](const auto& tmpError, const auto&, const auto&) { err = tmpError; });
+        if (err == Error::UNSUPPORTED) {
+            continue;
+        }
+        ASSERT_EQ(Error::NONE, err);
+
+        void* reservedRegion = nullptr;
+        uint64_t reservedSize = 0;
+        err = mGralloc->getReservedRegion(bufferHandle, &reservedRegion, &reservedSize);
+
+        ASSERT_EQ(Error::NONE, err);
+        ASSERT_NE(nullptr, reservedRegion);
+        ASSERT_EQ(requestedReservedSize, reservedSize);
+    }
+}
+
+/**
+ * Test IMapper::getReservedRegion() across multiple mappers
+ */
+TEST_F(GraphicsMapperHidlTest, GetReservedRegionMultiple) {
+    const native_handle_t* bufferHandle = nullptr;
+    auto info = mDummyDescriptorInfo;
+
+    const int pageSize = getpagesize();
+    ASSERT_GE(0, pageSize);
+    info.reservedSize = pageSize;
+
+    ASSERT_NO_FATAL_FAILURE(bufferHandle = mGralloc->allocate(info, true));
+
+    void* reservedRegion1 = nullptr;
+    uint64_t reservedSize1 = 0;
+    ASSERT_EQ(Error::NONE,
+              mGralloc->getReservedRegion(bufferHandle, &reservedRegion1, &reservedSize1));
+    ASSERT_NE(nullptr, reservedRegion1);
+    ASSERT_EQ(info.reservedSize, reservedSize1);
+
+    std::unique_ptr<Gralloc> anotherGralloc;
+    ASSERT_NO_FATAL_FAILURE(
+            anotherGralloc = std::make_unique<Gralloc>(
+                    GraphicsMapperHidlEnvironment::Instance()->getServiceName<IAllocator>(),
+                    GraphicsMapperHidlEnvironment::Instance()->getServiceName<IMapper>()));
+
+    void* reservedRegion2 = nullptr;
+    uint64_t reservedSize2 = 0;
+    ASSERT_EQ(Error::NONE,
+              mGralloc->getReservedRegion(bufferHandle, &reservedRegion2, &reservedSize2));
+    ASSERT_EQ(reservedRegion1, reservedRegion2);
+    ASSERT_EQ(reservedSize1, reservedSize2);
+}
+
+/**
+ * Test IMapper::getReservedRegion() with a bad buffer
+ */
+TEST_F(GraphicsMapperHidlTest, GetReservedRegionBadBuffer) {
+    const native_handle_t* bufferHandle = nullptr;
+
+    void* reservedRegion = nullptr;
+    uint64_t reservedSize = 0;
+    ASSERT_EQ(Error::BAD_BUFFER,
+              mGralloc->getReservedRegion(bufferHandle, &reservedRegion, &reservedSize));
+    ASSERT_EQ(nullptr, reservedRegion);
+    ASSERT_EQ(0, reservedSize);
+}
+
 }  // namespace
 }  // namespace vts
 }  // namespace V4_0