1 files changed, 100 insertions, 0 deletions
diff --git a/services/bufferhub/BufferNode.cpp b/services/bufferhub/BufferNode.cpp
new file mode 100644
index 0000000000..62583a666d
--- /dev/null
+++ b/services/bufferhub/BufferNode.cpp
@@ -0,0 +1,100 @@
+#include <errno.h>
+
+#include <bufferhub/BufferNode.h>
+#include <private/dvr/buffer_hub_defs.h>
+#include <ui/GraphicBufferAllocator.h>
+
+namespace android {
+namespace frameworks {
+namespace bufferhub {
+namespace V1_0 {
+namespace implementation {
+
+void BufferNode::InitializeMetadata() {
+    // Using placement new here to reuse shared memory instead of new allocation
+    // Initialize the atomic variables to zero.
+    dvr::BufferHubDefs::MetadataHeader* metadata_header = metadata_.metadata_header();
+    buffer_state_ = new (&metadata_header->buffer_state) std::atomic<uint64_t>(0);
+    fence_state_ = new (&metadata_header->fence_state) std::atomic<uint64_t>(0);
+    active_clients_bit_mask_ =
+            new (&metadata_header->active_clients_bit_mask) std::atomic<uint64_t>(0);
+}
+
+// Allocates a new BufferNode.
+BufferNode::BufferNode(uint32_t width, uint32_t height, uint32_t layer_count, uint32_t format,
+                       uint64_t usage, size_t user_metadata_size) {
+    uint32_t out_stride = 0;
+    // graphicBufferId is not used in GraphicBufferAllocator::allocate
+    // TODO(b/112338294) After move to the service folder, stop using the
+    // hardcoded service name "bufferhub".
+    int ret = GraphicBufferAllocator::get().allocate(width, height, format, layer_count, usage,
+                                                     const_cast<const native_handle_t**>(
+                                                             &buffer_handle_),
+                                                     &out_stride,
+                                                     /*graphicBufferId=*/0,
+                                                     /*requestor=*/"bufferhub");
+
+    if (ret != OK || buffer_handle_ == nullptr) {
+        ALOGE("BufferNode::BufferNode: Failed to allocate buffer: %s", strerror(-ret));
+        return;
+    }
+
+    buffer_desc_.width = width;
+    buffer_desc_.height = height;
+    buffer_desc_.layers = layer_count;
+    buffer_desc_.format = format;
+    buffer_desc_.usage = usage;
+    buffer_desc_.stride = out_stride;
+
+    metadata_ = BufferHubMetadata::Create(user_metadata_size);
+    if (!metadata_.IsValid()) {
+        ALOGE("BufferNode::BufferNode: Failed to allocate metadata.");
+        return;
+    }
+    InitializeMetadata();
+}
+
+// Free the handle
+BufferNode::~BufferNode() {
+    if (buffer_handle_ != nullptr) {
+        status_t ret = GraphicBufferAllocator::get().free(buffer_handle_);
+        if (ret != OK) {
+            ALOGE("BufferNode::~BufferNode: Failed to free handle; Got error: %d", ret);
+        }
+    }
+}
+
+uint64_t BufferNode::GetActiveClientsBitMask() const {
+    return active_clients_bit_mask_->load(std::memory_order_acquire);
+}
+
+uint64_t BufferNode::AddNewActiveClientsBitToMask() {
+    uint64_t current_active_clients_bit_mask = GetActiveClientsBitMask();
+    uint64_t client_state_mask = 0ULL;
+    uint64_t updated_active_clients_bit_mask = 0ULL;
+    do {
+        client_state_mask = dvr::BufferHubDefs::FindNextAvailableClientStateMask(
+                current_active_clients_bit_mask);
+        if (client_state_mask == 0ULL) {
+            ALOGE("BufferNode::AddNewActiveClientsBitToMask: reached the maximum "
+                  "mumber of channels per buffer node: 32.");
+            errno = E2BIG;
+            return 0ULL;
+        }
+        updated_active_clients_bit_mask = current_active_clients_bit_mask | client_state_mask;
+    } while (!(active_clients_bit_mask_->compare_exchange_weak(current_active_clients_bit_mask,
+                                                               updated_active_clients_bit_mask,
+                                                               std::memory_order_acq_rel,
+                                                               std::memory_order_acquire)));
+    return client_state_mask;
+}
+
+void BufferNode::RemoveClientsBitFromMask(const uint64_t& value) {
+    active_clients_bit_mask_->fetch_and(~value);
+}
+
+} // namespace implementation
+} // namespace V1_0
+} // namespace bufferhub
+} // namespace frameworks
+} // namespace android