// Copyright 2019 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#ifndef MEDIA_GPU_V4L2_V4L2_VIDEO_DECODER_H_
#define MEDIA_GPU_V4L2_V4L2_VIDEO_DECODER_H_
#include <linux/videodev2.h>
#include <map>
#include <memory>
#include <optional>
#include <utility>
#include <vector>
#include "base/functional/callback_forward.h"
#include "base/memory/scoped_refptr.h"
#include "base/memory/weak_ptr.h"
#include "base/sequence_checker.h"
#include "base/task/sequenced_task_runner.h"
#include "base/threading/thread.h"
#include "base/time/time.h"
#include "media/base/cdm_context.h"
#include "media/base/supported_video_decoder_config.h"
#include "media/base/video_aspect_ratio.h"
#include "media/base/video_types.h"
#include "media/gpu/chromeos/chromeos_status.h"
#include "media/gpu/chromeos/gpu_buffer_layout.h"
#include "media/gpu/chromeos/video_decoder_pipeline.h"
#include "media/gpu/media_gpu_export.h"
#include "media/gpu/v4l2/v4l2_device.h"
#include "media/gpu/v4l2/v4l2_status.h"
#include "media/gpu/v4l2/v4l2_video_decoder_backend.h"
#include "ui/gfx/geometry/size.h"
namespace media {
class DmabufVideoFramePool;
class MEDIA_GPU_EXPORT V4L2VideoDecoder
: public VideoDecoderMixin,
public V4L2VideoDecoderBackend::Client {
public:
// Create V4L2VideoDecoder instance. The success of the creation doesn't
// ensure V4L2VideoDecoder is available on the device. It will be
// determined in Initialize().
static std::unique_ptr<VideoDecoderMixin> Create(
std::unique_ptr<MediaLog> media_log,
scoped_refptr<base::SequencedTaskRunner> decoder_task_runner,
base::WeakPtr<VideoDecoderMixin::Client> client);
static std::optional<SupportedVideoDecoderConfigs> GetSupportedConfigs();
// VideoDecoderMixin implementation, VideoDecoder part.
void Initialize(const VideoDecoderConfig& config,
bool low_delay,
CdmContext* cdm_context,
InitCB init_cb,
const PipelineOutputCB& output_cb,
const WaitingCB& waiting_cb) override;
void Decode(scoped_refptr<DecoderBuffer> buffer, DecodeCB decode_cb) override;
void Reset(base::OnceClosure reset_cb) override;
bool NeedsBitstreamConversion() const override;
bool CanReadWithoutStalling() const override;
int GetMaxDecodeRequests() const override;
VideoDecoderType GetDecoderType() const override;
bool IsPlatformDecoder() const override;
// VideoDecoderMixin implementation, specific part.
void ApplyResolutionChange() override;
size_t GetMaxOutputFramePoolSize() const override;
bool NeedsTranscryption() override;
CroStatus AttachSecureBuffer(scoped_refptr<DecoderBuffer>& buffer) override;
void ReleaseSecureBuffer(uint64_t secure_handle) override;
// V4L2VideoDecoderBackend::Client implementation
void OnBackendError() override;
bool IsDecoding() const override;
void InitiateFlush() override;
void CompleteFlush() override;
void RestartStream() override;
void ChangeResolution(gfx::Size pic_size,
gfx::Rect visible_rect,
size_t num_codec_reference_frames,
uint8_t bit_depth) override;
void OutputFrame(scoped_refptr<FrameResource> frame,
const gfx::Rect& visible_rect,
const VideoColorSpace& color_space,
base::TimeDelta timestamp) override;
DmabufVideoFramePool* GetVideoFramePool() const override;
void SetDmaIncoherentV4L2(bool incoherent) override;
private:
friend class V4L2VideoDecoderTest;
V4L2VideoDecoder(std::unique_ptr<MediaLog> media_log,
scoped_refptr<base::SequencedTaskRunner> decoder_task_runner,
base::WeakPtr<VideoDecoderMixin::Client> client,
scoped_refptr<V4L2Device> device);
~V4L2VideoDecoder() override;
enum class State {
// Initial state. Transitions to |kInitialized| if Initialize() is
// successful,
// |kError| otherwise.
kUninitialized,
// Transitions to |kDecoding| when an input buffer has arrived that
// allows creation of hardware contexts. |kError| on error.
kInitialized,
// Transitions to |kFlushing| when flushing or changing resolution,
// |kError| if any unexpected error occurs.
kDecoding,
// Transitions to |kDecoding| when flushing or changing resolution is
// finished. Do not process new input buffer in this state.
kFlushing,
// Error state. Cannot transition to other state anymore.
kError,
};
// Setup format for input queue.
bool SetupInputFormat();
// Allocates the buffers for the input queue.
bool AllocateInputBuffers();
// Setup format for output queue. This function sets output format on output
// queue that is supported by a v4l2 driver, can be allocatable by
// VideoFramePool and can be composited by chrome. This also updates format
// in VideoFramePool.
// Return CroStatus::Codes::kOk if the setup is successful.
// Return CroStatus::Codes::kResetRequired if the setup is aborted.
// Return CroStatus::Codes::kFailedToChangeResolution if other error occurs.
CroStatus SetupOutputFormat(const gfx::Size& size,
const gfx::Rect& visible_rect,
size_t num_codec_reference_frames,
uint8_t bit_depth);
// Sends the EXT_CTRLS ioctl for 10-bit video at the specified |size|. This
// will enable retrieving the proper format from the CAPTURE queue. |size| is
// needed so that we are passing in all the information that might be needed
// by the driver to know what the format is.
CroStatus SetExtCtrls10Bit(const gfx::Size& size);
// Start streaming V4L2 input and (if |start_output_queue| is true) output
// queues. Attempt to start |device_poll_thread_| after streaming starts.
bool StartStreamV4L2Queue(bool start_output_queue);
// Stop streaming V4L2 output and (if |stop_input_queue| is true) input
// queues. Stop |device_poll_thread_| before stopping streaming.
bool StopStreamV4L2Queue(bool stop_input_queue);
// Try to dequeue input and output buffers from device.
void ServiceDeviceTask(bool event);
// After the pipeline finished flushing frames, reconfigure the resolution
// setting of V4L2 device and the frame pool.
// Return CroStatus::Codes::kOk if the process is done successfully.
// Return CroStatus::Codes::kResetRequired if the process is aborted by reset.
// Return CroStatus::Codes::kFailedToChangeResolution if any error occurs.
CroStatus ContinueChangeResolution(const gfx::Size& pic_size,
const gfx::Rect& visible_rect,
size_t num_codec_reference_frames,
uint8_t bit_depth);
void OnChangeResolutionDone(CroStatus status);
// Change the state and check the state transition is valid.
void SetState(State new_state);
// Continue backend initialization. Decoder will not take a hardware context
// until InitializeBackend() is called.
V4L2Status InitializeBackend();
// Performs allocation of a secure buffer by invoking the Mojo call on the
// CdmContext. This will only invoke the passed in callback on a successful
// allocation, otherwise this will cause the decoder init to fail.
void AllocateSecureBuffer(uint32_t size, SecureBufferAllocatedCB callback);
// Callback from invoking the Mojo call to allocate a secure buffer. This
// validates the FD and also resolves it to a secure handle before invoking
// the callback. If there's anything wrong with the passed in arguments or
// resolving the handle, this will cause a failure in decoder initialization.
void AllocateSecureBufferCB(SecureBufferAllocatedCB callback,
mojo::PlatformHandle secure_buffer);
// Pages with multiple V4L2VideoDecoder instances might run out of memory
// (e.g. b/170870476) or crash (e.g. crbug.com/1109312). To avoid that and
// while the investigation goes on, limit the maximum number of simultaneous
// decoder instances for now. |num_instances_| tracks the number of
// simultaneous decoders. |can_use_decoder_| is true iff we haven't reached
// the maximum number of instances at the time this decoder is created.
static constexpr int kMaxNumOfInstances = 32;
static base::AtomicRefCount num_instances_;
bool can_use_decoder_ = false;
// The V4L2 backend, i.e. the part of the decoder that sends
// decoding jobs to the kernel.
std::unique_ptr<V4L2VideoDecoderBackend> backend_;
// V4L2 device in use.
scoped_refptr<V4L2Device> device_;
// Callback to change resolution, called after the pipeline is flushed.
base::OnceClosure continue_change_resolution_cb_;
// State of the instance.
State state_ = State::kUninitialized;
// Aspect ratio from config to use for output frames.
VideoAspectRatio aspect_ratio_;
// Callbacks passed from Initialize().
PipelineOutputCB output_cb_;
// Hold onto profile and color space passed in from Initialize() so that
// it is available for InitializeBackend().
VideoCodecProfile profile_ = VIDEO_CODEC_PROFILE_UNKNOWN;
VideoColorSpace color_space_;
// Hold onto the current resolution so we can use that to determine the size
// of the input(OUTPUT) buffers.
gfx::Size current_resolution_;
// Hold onto the input fourcc format so we can use it if we need to rebuild
// the input queue.
uint32_t input_format_fourcc_;
// V4L2 input and output queue.
scoped_refptr<V4L2Queue> input_queue_;
scoped_refptr<V4L2Queue> output_queue_;
// We need to use a CdmContextRef to ensure the lifetime of the CdmContext
// backing it while we are alive. This also indicates secure playback mode.
std::unique_ptr<CdmContextRef> cdm_context_ref_;
uint32_t pending_secure_allocate_callbacks_ = 0;
InitCB pending_init_cb_;
CroStatus pending_change_resolution_done_status_;
SEQUENCE_CHECKER(decoder_sequence_checker_);
// Whether or not our V4L2Queues should be requested with
// V4L2_MEMORY_FLAG_NON_COHERENT
bool incoherent_ = false;
// |weak_this_for_polling_| must be dereferenced and invalidated on
// |decoder_task_runner_|.
base::WeakPtr<V4L2VideoDecoder> weak_this_for_polling_;
base::WeakPtrFactory<V4L2VideoDecoder> weak_this_for_polling_factory_;
base::WeakPtrFactory<V4L2VideoDecoder> weak_this_for_callbacks_{this};
};
} // namespace media
#endif // MEDIA_GPU_V4L2_V4L2_VIDEO_DECODER_H_