/* SPDX-License-Identifier: LGPL-2.1-or-later */ /* * Copyright (C) 2020, Collabora Ltd. * Author: Nicolas Dufresne <nicolas.dufresne@collabora.com> * * gstlibcameraallocator.cpp - GStreamer Custom Allocator */ #include "gstlibcameraallocator.h" #include <libcamera/camera.h> #include <libcamera/framebuffer_allocator.h> #include <libcamera/stream.h> #include "gstlibcamera-utils.h" using namespace libcamera; static gboolean gst_libcamera_allocator_release(GstMiniObject *mini_object); /** * \struct FrameWrap * \brief An internal wrapper to track the relation between FrameBuffer and * GstMemory(s) * * This wrapper maintains a count of the outstanding GstMemory (there may be * multiple GstMemory per FrameBuffer), and give back the FrameBuffer to the * allocator pool when all memory objects have returned. */ struct FrameWrap { FrameWrap(GstAllocator *allocator, FrameBuffer *buffer, gpointer stream); ~FrameWrap(); void acquirePlane() { ++outstandingPlanes_; } bool releasePlane() { return --outstandingPlanes_ == 0; } static GQuark getQuark(); gpointer stream_; FrameBuffer *buffer_; std::vector<GstMemory *> planes_; gint outstandingPlanes_; }; FrameWrap::FrameWrap(GstAllocator *allocator, FrameBuffer *buffer, gpointer stream) : stream_(stream), buffer_(buffer), outstandingPlanes_(0) { for (const FrameBuffer::Plane &plane : buffer->planes()) { GstMemory *mem = gst_fd_allocator_alloc(allocator, plane.fd.fd(), plane.length, GST_FD_MEMORY_FLAG_DONT_CLOSE); gst_mini_object_set_qdata(GST_MINI_OBJECT(mem), getQuark(), this, nullptr); GST_MINI_OBJECT(mem)->dispose = gst_libcamera_allocator_release; g_object_unref(mem->allocator); planes_.push_back(mem); } } FrameWrap::~FrameWrap() { for (GstMemory *mem : planes_) { GST_MINI_OBJECT(mem)->dispose = nullptr; g_object_ref(mem->allocator); gst_memory_unref(mem); } } GQuark FrameWrap::getQuark() { static gsize frame_quark = 0; if (g_once_init_enter(&frame_quark)) { GQuark quark = g_quark_from_string("GstLibcameraFrameWrap"); g_once_init_leave(&frame_quark, quark); } return frame_quark; } /** * \struct _GstLibcameraAllocator * \brief A pooling GstDmaBufAllocator for libcamera * * This is a pooling GstDmaBufAllocator implementation. This implementation override * the dispose function of memory object in order to keep them alive when they * are disposed by downstream elements. */ struct _GstLibcameraAllocator { GstDmaBufAllocator parent; FrameBufferAllocator *fb_allocator; /* * A hash table using Stream pointer as key and returning a GQueue of * FrameWrap. */ GHashTable *pools; }; G_DEFINE_TYPE(GstLibcameraAllocator, gst_libcamera_allocator, GST_TYPE_DMABUF_ALLOCATOR) static gboolean gst_libcamera_allocator_release(GstMiniObject *mini_object) { GstMemory *mem = GST_MEMORY_CAST(mini_object); GstLibcameraAllocator *self = GST_LIBCAMERA_ALLOCATOR(mem->allocator); GLibLocker lock(GST_OBJECT(self)); auto *frame = reinterpret_cast<FrameWrap *>(gst_mini_object_get_qdata(mini_object, FrameWrap::getQuark())); gst_memory_ref(mem); if (frame->releasePlane()) { auto *pool = reinterpret_cast<GQueue *>(g_hash_table_lookup(self->pools, frame->stream_)); g_return_val_if_fail(pool, TRUE); g_queue_push_tail(pool, frame); } /* Keep last in case we are holding on the last allocator ref. */ g_object_unref(mem->allocator); /* Return FALSE so that our mini object isn't freed. */ return FALSE; } static void gst_libcamera_allocator_free_pool(gpointer data) { GQueue *queue = reinterpret_cast<GQueue *>(data); FrameWrap *frame; while ((frame = reinterpret_cast<FrameWrap *>(g_queue_pop_head(queue)))) { g_warn_if_fail(frame->outstandingPlanes_ == 0); delete frame; } g_queue_free(queue); } static void gst_libcamera_allocator_init(GstLibcameraAllocator *self) { self->pools = g_hash_table_new_full(nullptr, nullptr, nullptr, gst_libcamera_allocator_free_pool); GST_OBJECT_FLAG_SET(self, GST_ALLOCATOR_FLAG_CUSTOM_ALLOC); } static void gst_libcamera_allocator_dispose(GObject *object) { GstLibcameraAllocator *self = GST_LIBCAMERA_ALLOCATOR(object); if (self->pools) { g_hash_table_unref(self->pools); self->pools = nullptr; } G_OBJECT_CLASS(gst_libcamera_allocator_parent_class)->dispose(object); } static void gst_libcamera_allocator_finalize(GObject *object) { GstLibcameraAllocator *self = GST_LIBCAMERA_ALLOCATOR(object); delete self->fb_allocator; G_OBJECT_CLASS(gst_libcamera_allocator_parent_class)->finalize(object); } static void gst_libcamera_allocator_class_init(GstLibcameraAllocatorClass *klass) { auto *allocator_class = GST_ALLOCATOR_CLASS(klass); auto *object_class = G_OBJECT_CLASS(klass); object_class->dispose = gst_libcamera_allocator_dispose; object_class->finalize = gst_libcamera_allocator_finalize; allocator_class->alloc = nullptr; } GstLibcameraAllocator * gst_libcamera_allocator_new(std::shared_ptr<Camera> camera) { auto *self = GST_LIBCAMERA_ALLOCATOR(g_object_new(GST_TYPE_LIBCAMERA_ALLOCATOR, nullptr)); self->fb_allocator = new FrameBufferAllocator(camera); for (Stream *stream : camera->streams()) { gint ret; ret = self->fb_allocator->allocate(stream); if (ret == 0) return nullptr; GQueue *pool = g_queue_new(); for (const std::unique_ptr<FrameBuffer> &buffer : self->fb_allocator->buffers(stream)) { auto *fb = new FrameWrap(GST_ALLOCATOR(self), buffer.get(), stream); g_queue_push_tail(pool, fb); } g_hash_table_insert(self->pools, stream, pool); } return self; } bool gst_libcamera_allocator_prepare_buffer(GstLibcameraAllocator *self, Stream *stream, GstBuffer *buffer) { GLibLocker lock(GST_OBJECT(self)); auto *pool = reinterpret_cast<GQueue *>(g_hash_table_lookup(self->pools, stream)); g_return_val_if_fail(pool, false); auto *frame = reinterpret_cast<FrameWrap *>(g_queue_pop_head(pool)); if (!frame) return false; for (GstMemory *mem : frame->planes_) { frame->acquirePlane(); gst_buffer_append_memory(buffer, mem); g_object_ref(mem->allocator); } return true; } gsize gst_libcamera_allocator_get_pool_size(GstLibcameraAllocator *self, Stream *stream) { GLibLocker lock(GST_OBJECT(self)); auto *pool = reinterpret_cast<GQueue *>(g_hash_table_lookup(self->pools, stream)); g_return_val_if_fail(pool, false); return pool->length; } FrameBuffer * gst_libcamera_memory_get_frame_buffer(GstMemory *mem) { auto *frame = reinterpret_cast<FrameWrap *>(gst_mini_object_get_qdata(GST_MINI_OBJECT_CAST(mem), FrameWrap::getQuark())); return frame->buffer_; }