gstreamer/gst-libs/gst/allocators/gstdmabuf.h

119 lines
4.2 KiB
C

/* GStreamer dmabuf allocator
* Copyright (C) 2013 Linaro SA
* Author: Benjamin Gaignard <benjamin.gaignard@linaro.org> for Linaro.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
#ifndef __GST_DMABUF_H__
#define __GST_DMABUF_H__
#include <gst/gst.h>
#include <gst/allocators/gstfdmemory.h>
G_BEGIN_DECLS
/**
* GST_CAPS_FEATURE_MEMORY_DMABUF:
*
* Constant that defines the caps feature name for DMA buffer sharing.
*
* It has to be used for non-mappable dma-buf only, i.e. when the underlying
* memory is not mappable to user space. Or when the mapped memory contains
* non meaningful data. It can be the case for protected content or when the
* user wants explicitly avoid any software post processing.
*
* In these cases all elements between the exported and the importer has to work
* in passthrough mode. This is done by adding this caps feature.
*
* When the memory is mappable for read and write requests then it is assumes
* to be a fast path and so this caps feature should not be used. Though
* according to the dma-buf protocal, while it is mapped it prevents the
* exporter to migrate the buffer.
*
* This caps feature should not serve at all the purpose of selecting the
* @GST_ALLOCATOR_DMABUF allocator during caps negotiation.
* When the exporter is the upstream element from the importer point of view,
* the exporter should try to map the dma buffer at runtime (preferrably during
* decide_allocation phase). When it succeeds for #GST_MAP_READWRITE this caps
* feature should not be used. This allows scalers, color converts and any image
* processing filters to work directly on the dma buffer.
* In this case the importer element should check all incomming memory using
* gst_is_dmabuf_memory().
*
* Since: 1.11
*/
#define GST_CAPS_FEATURE_MEMORY_DMABUF "memory:DMABuf"
#define GST_ALLOCATOR_DMABUF "dmabuf"
#define GST_TYPE_DMABUF_ALLOCATOR (gst_dmabuf_allocator_get_type())
#define GST_IS_DMABUF_ALLOCATOR(obj) (G_TYPE_CHECK_INSTANCE_TYPE ((obj), GST_TYPE_DMABUF_ALLOCATOR))
#define GST_IS_DMABUF_ALLOCATOR_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE ((klass), GST_TYPE_DMABUF_ALLOCATOR))
#define GST_DMABUF_ALLOCATOR_GET_CLASS(obj) (G_TYPE_INSTANCE_GET_CLASS ((obj), GST_TYPE_DMABUF_ALLOCATOR, GstDmaBufAllocatorClass))
#define GST_DMABUF_ALLOCATOR(obj) (G_TYPE_CHECK_INSTANCE_CAST ((obj), GST_TYPE_DMABUF_ALLOCATOR, GstDmaBufAllocator))
#define GST_DMABUF_ALLOCATOR_CLASS(klass) (G_TYPE_CHECK_CLASS_CAST ((klass), GST_TYPE_DMABUF_ALLOCATOR, GstDmaBufAllocatorClass))
#define GST_DMABUF_ALLOCATOR_CAST(obj) ((GstDmaBufAllocator *)(obj))
typedef struct _GstDmaBufAllocator GstDmaBufAllocator;
typedef struct _GstDmaBufAllocatorClass GstDmaBufAllocatorClass;
/**
* GstDmaBufAllocator:
*
* Base class for allocators with dmabuf-backed memory
*
* Since: 1.12
*/
struct _GstDmaBufAllocator
{
GstFdAllocator parent;
/*< private >*/
gpointer _gst_reserved[GST_PADDING];
};
struct _GstDmaBufAllocatorClass
{
GstFdAllocatorClass parent_class;
/*< private >*/
gpointer _gst_reserved[GST_PADDING];
};
GST_EXPORT
GType gst_dmabuf_allocator_get_type (void);
GST_EXPORT
GstAllocator * gst_dmabuf_allocator_new (void);
GST_EXPORT
GstMemory * gst_dmabuf_allocator_alloc (GstAllocator * allocator, gint fd, gsize size);
GST_EXPORT
gint gst_dmabuf_memory_get_fd (GstMemory * mem);
GST_EXPORT
gboolean gst_is_dmabuf_memory (GstMemory * mem);
#ifdef G_DEFINE_AUTOPTR_CLEANUP_FUNC
G_DEFINE_AUTOPTR_CLEANUP_FUNC(GstDmaBufAllocator, gst_object_unref)
#endif
G_END_DECLS
#endif /* __GST_DMABUF_H__ */