gstreamer/sys/v4l2/gstv4l2bufferpool.c

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/* GStreamer
*
* Copyright (C) 2001-2002 Ronald Bultje <rbultje@ronald.bitfreak.net>
* 2006 Edgard Lima <edgard.lima@indt.org.br>
* 2009 Texas Instruments, Inc - http://www.ti.com/
*
* gstv4l2bufferpool.c V4L2 buffer pool class
*
* 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., 51 Franklin St, Fifth Floor,
* Boston, MA 02110-1301, USA.
*/
#ifdef HAVE_CONFIG_H
# include <config.h>
#endif
#if HAVE_DECL_V4L2_MEMORY_DMABUF
#ifndef _GNU_SOURCE
# define _GNU_SOURCE /* O_CLOEXEC */
#endif
#include <fcntl.h>
#endif
#include <sys/mman.h>
#include <string.h>
#include <unistd.h>
#include "gst/video/video.h"
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#include "gst/video/gstvideometa.h"
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#include "gst/video/gstvideopool.h"
#include "gst/allocators/gstdmabuf.h"
#include <gstv4l2bufferpool.h>
#include "v4l2_calls.h"
#include "gst/gst-i18n-plugin.h"
#include <gst/glib-compat-private.h>
/* videodev2.h is not versioned and we can't easily check for the presence
* of enum values at compile time, but the V4L2_CAP_VIDEO_OUTPUT_OVERLAY define
* was added in the same commit as V4L2_FIELD_INTERLACED_{TB,BT} (b2787845) */
#ifndef V4L2_CAP_VIDEO_OUTPUT_OVERLAY
#define V4L2_FIELD_INTERLACED_TB 8
#define V4L2_FIELD_INTERLACED_BT 9
#endif
GST_DEBUG_CATEGORY_EXTERN (v4l2_debug);
#define GST_CAT_DEFAULT v4l2_debug
/*
* GstV4l2Buffer:
*/
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GType
gst_v4l2_meta_api_get_type (void)
{
static volatile GType type;
static const gchar *tags[] =
{ GST_META_TAG_VIDEO_STR, GST_META_TAG_MEMORY_STR, NULL };
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if (g_once_init_enter (&type)) {
GType _type = gst_meta_api_type_register ("GstV4l2MetaAPI", tags);
g_once_init_leave (&type, _type);
}
return type;
}
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const GstMetaInfo *
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gst_v4l2_meta_get_info (void)
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{
static const GstMetaInfo *meta_info = NULL;
if (g_once_init_enter (&meta_info)) {
const GstMetaInfo *meta =
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gst_meta_register (gst_v4l2_meta_api_get_type (), "GstV4l2Meta",
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sizeof (GstV4l2Meta), (GstMetaInitFunction) NULL,
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(GstMetaFreeFunction) NULL, (GstMetaTransformFunction) NULL);
g_once_init_leave (&meta_info, meta);
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}
return meta_info;
}
/*
* GstV4l2BufferPool:
*/
#define gst_v4l2_buffer_pool_parent_class parent_class
G_DEFINE_TYPE (GstV4l2BufferPool, gst_v4l2_buffer_pool, GST_TYPE_BUFFER_POOL);
static void gst_v4l2_buffer_pool_release_buffer (GstBufferPool * bpool,
GstBuffer * buffer);
static void
gst_v4l2_buffer_pool_free_buffer (GstBufferPool * bpool, GstBuffer * buffer)
{
GstV4l2BufferPool *pool = GST_V4L2_BUFFER_POOL (bpool);
GstV4l2Object *obj;
obj = pool->obj;
switch (obj->mode) {
case GST_V4L2_IO_RW:
case GST_V4L2_IO_DMABUF:
break;
case GST_V4L2_IO_MMAP:
{
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GstV4l2Meta *meta;
gint index;
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meta = GST_V4L2_META_GET (buffer);
g_assert (meta != NULL);
index = meta->vbuffer.index;
GST_LOG_OBJECT (pool,
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"unmap buffer %p idx %d (data %p, len %u)", buffer,
index, meta->mem, meta->vbuffer.length);
v4l2_munmap (meta->mem, meta->vbuffer.length);
pool->buffers[index] = NULL;
break;
}
case GST_V4L2_IO_USERPTR:
default:
g_assert_not_reached ();
break;
}
gst_buffer_unref (buffer);
}
static GstFlowReturn
gst_v4l2_buffer_pool_alloc_buffer (GstBufferPool * bpool, GstBuffer ** buffer,
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GstBufferPoolAcquireParams * params)
{
GstV4l2BufferPool *pool = GST_V4L2_BUFFER_POOL (bpool);
GstBuffer *newbuf;
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GstV4l2Meta *meta;
GstV4l2Object *obj;
GstVideoInfo *info;
guint index;
obj = pool->obj;
info = &obj->info;
switch (obj->mode) {
case GST_V4L2_IO_RW:
{
newbuf =
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gst_buffer_new_allocate (pool->allocator, pool->size, &pool->params);
break;
}
case GST_V4L2_IO_MMAP:
case GST_V4L2_IO_DMABUF:
{
#ifdef VIDIOC_CREATE_BUFS
if (pool->num_allocated == pool->num_buffers) {
struct v4l2_create_buffers create_bufs;
memset (&create_bufs, 0, sizeof (struct v4l2_create_buffers));
create_bufs.count = 1;
create_bufs.memory = V4L2_MEMORY_MMAP;
create_bufs.format.type = obj->type;
if (v4l2_ioctl (pool->video_fd, VIDIOC_G_FMT, &create_bufs.format) < 0)
goto g_fmt_failed;
if (v4l2_ioctl (pool->video_fd, VIDIOC_CREATE_BUFS, &create_bufs) < 0)
goto create_bufs_failed;
GST_LOG_OBJECT (pool, "created buffer with index: %u",
create_bufs.index);
pool->num_buffers++;
pool->buffers = g_renew (GstBuffer *, pool->buffers, pool->num_buffers);
pool->buffers[pool->num_buffers - 1] = NULL;
}
#endif
newbuf = gst_buffer_new ();
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meta = GST_V4L2_META_ADD (newbuf);
index = pool->num_allocated;
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GST_LOG_OBJECT (pool, "creating buffer %u, %p", index, newbuf);
meta->vbuffer.index = index;
meta->vbuffer.type = obj->type;
meta->vbuffer.memory = V4L2_MEMORY_MMAP;
if (v4l2_ioctl (pool->video_fd, VIDIOC_QUERYBUF, &meta->vbuffer) < 0)
goto querybuf_failed;
GST_LOG_OBJECT (pool, " index: %u", meta->vbuffer.index);
GST_LOG_OBJECT (pool, " type: %d", meta->vbuffer.type);
GST_LOG_OBJECT (pool, " bytesused: %u", meta->vbuffer.bytesused);
GST_LOG_OBJECT (pool, " flags: %08x", meta->vbuffer.flags);
GST_LOG_OBJECT (pool, " field: %d", meta->vbuffer.field);
GST_LOG_OBJECT (pool, " memory: %d", meta->vbuffer.memory);
if (meta->vbuffer.memory == V4L2_MEMORY_MMAP)
GST_LOG_OBJECT (pool, " MMAP offset: %u", meta->vbuffer.m.offset);
if (obj->mode == GST_V4L2_IO_MMAP) {
meta->mem = v4l2_mmap (0, meta->vbuffer.length,
PROT_READ | PROT_WRITE, MAP_SHARED, pool->video_fd,
meta->vbuffer.m.offset);
if (meta->mem == MAP_FAILED)
goto mmap_failed;
gst_buffer_append_memory (newbuf,
gst_memory_new_wrapped (GST_MEMORY_FLAG_NO_SHARE,
meta->mem, meta->vbuffer.length, 0, meta->vbuffer.length, NULL,
NULL));
}
#if HAVE_DECL_V4L2_MEMORY_DMABUF
if (obj->mode == GST_V4L2_IO_DMABUF) {
struct v4l2_exportbuffer expbuf;
memset (&expbuf, 0, sizeof (struct v4l2_exportbuffer));
expbuf.type = meta->vbuffer.type;
expbuf.index = meta->vbuffer.index;
expbuf.flags = O_CLOEXEC;
if (v4l2_ioctl (pool->video_fd, VIDIOC_EXPBUF, &expbuf) < 0)
goto expbuf_failed;
meta->vbuffer.memory = V4L2_MEMORY_DMABUF;
gst_buffer_append_memory (newbuf,
gst_dmabuf_allocator_alloc (pool->allocator, expbuf.fd,
meta->vbuffer.length));
}
#endif
/* add metadata to raw video buffers */
if (pool->add_videometa && info->finfo) {
const GstVideoFormatInfo *finfo = info->finfo;
gsize offset[GST_VIDEO_MAX_PLANES];
gint width, height, n_planes, offs, i, stride[GST_VIDEO_MAX_PLANES];
width = GST_VIDEO_INFO_WIDTH (info);
height = GST_VIDEO_INFO_HEIGHT (info);
n_planes = GST_VIDEO_INFO_N_PLANES (info);
GST_DEBUG_OBJECT (pool, "adding video meta, bytesperline %d",
obj->bytesperline);
offs = 0;
for (i = 0; i < n_planes; i++) {
offset[i] = offs;
switch (info->finfo->format) {
case GST_VIDEO_FORMAT_NV12:
case GST_VIDEO_FORMAT_NV21:
case GST_VIDEO_FORMAT_NV16:
case GST_VIDEO_FORMAT_NV24:
stride[i] =
(i == 0 ? 1 : 2) * GST_VIDEO_FORMAT_INFO_SCALE_WIDTH (finfo,
i, obj->bytesperline);
break;
default:
stride[i] =
GST_VIDEO_FORMAT_INFO_SCALE_WIDTH (finfo, i,
obj->bytesperline);
break;
}
offs +=
stride[i] * GST_VIDEO_FORMAT_INFO_SCALE_HEIGHT (finfo, i, height);
}
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gst_buffer_add_video_meta_full (newbuf, GST_VIDEO_FRAME_FLAG_NONE,
GST_VIDEO_INFO_FORMAT (info), width, height, n_planes,
offset, stride);
}
break;
}
case GST_V4L2_IO_USERPTR:
default:
newbuf = NULL;
g_assert_not_reached ();
}
pool->num_allocated++;
*buffer = newbuf;
return GST_FLOW_OK;
/* ERRORS */
#ifdef VIDIOC_CREATE_BUFS
g_fmt_failed:
{
gint errnosave = errno;
GST_WARNING ("Failed G_FMT: %s", g_strerror (errnosave));
errno = errnosave;
return GST_FLOW_ERROR;
}
create_bufs_failed:
{
gint errnosave = errno;
GST_WARNING ("Failed CREATE_BUFS: %s", g_strerror (errnosave));
errno = errnosave;
return GST_FLOW_ERROR;
}
#endif
querybuf_failed:
{
gint errnosave = errno;
GST_WARNING ("Failed QUERYBUF: %s", g_strerror (errnosave));
gst_buffer_unref (newbuf);
errno = errnosave;
return GST_FLOW_ERROR;
}
mmap_failed:
{
gint errnosave = errno;
GST_WARNING ("Failed to mmap: %s", g_strerror (errnosave));
gst_buffer_unref (newbuf);
errno = errnosave;
return GST_FLOW_ERROR;
}
#if HAVE_DECL_V4L2_MEMORY_DMABUF
expbuf_failed:
{
gint errnosave = errno;
GST_WARNING ("Failed EXPBUF: %s", g_strerror (errnosave));
gst_buffer_unref (newbuf);
errno = errnosave;
return GST_FLOW_ERROR;
}
#endif
}
static gboolean
gst_v4l2_buffer_pool_set_config (GstBufferPool * bpool, GstStructure * config)
{
GstV4l2BufferPool *pool = GST_V4L2_BUFFER_POOL (bpool);
GstV4l2Object *obj = pool->obj;
GstCaps *caps;
guint size, min_buffers, max_buffers, num_buffers, copy_threshold;
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GstAllocator *allocator;
GstAllocationParams params;
struct v4l2_requestbuffers breq;
GST_DEBUG_OBJECT (pool, "set config");
pool->add_videometa =
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gst_buffer_pool_config_has_option (config,
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GST_BUFFER_POOL_OPTION_VIDEO_META);
if (!pool->add_videometa &&
GST_VIDEO_INFO_FORMAT (&obj->info) != GST_VIDEO_FORMAT_ENCODED) {
gint stride;
/* we don't have video metadata, and we are not dealing with raw video,
* see if the strides are compatible */
stride = GST_VIDEO_INFO_PLANE_STRIDE (&obj->info, 0);
GST_DEBUG_OBJECT (pool, "no videometadata, checking strides %d and %u",
stride, obj->bytesperline);
if (stride != obj->bytesperline)
goto missing_video_api;
}
/* parse the config and keep around */
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if (!gst_buffer_pool_config_get_params (config, &caps, &size, &min_buffers,
&max_buffers))
goto wrong_config;
if (!gst_buffer_pool_config_get_allocator (config, &allocator, &params))
goto wrong_config;
GST_DEBUG_OBJECT (pool, "config %" GST_PTR_FORMAT, config);
switch (obj->mode) {
case GST_V4L2_IO_RW:
/* we preallocate 1 buffer, this value also instructs the latency
* calculation to have 1 frame latency max */
num_buffers = 1;
copy_threshold = 0;
break;
case GST_V4L2_IO_DMABUF:
case GST_V4L2_IO_MMAP:
{
/* request a reasonable number of buffers when no max specified. We will
* copy when we run out of buffers */
if (max_buffers == 0)
num_buffers = 4;
else
num_buffers = max_buffers;
/* first, lets request buffers, and see how many we can get: */
GST_DEBUG_OBJECT (pool, "starting, requesting %d MMAP buffers",
num_buffers);
memset (&breq, 0, sizeof (struct v4l2_requestbuffers));
breq.type = obj->type;
breq.count = num_buffers;
breq.memory = V4L2_MEMORY_MMAP;
if (v4l2_ioctl (pool->video_fd, VIDIOC_REQBUFS, &breq) < 0)
goto reqbufs_failed;
GST_LOG_OBJECT (pool, " count: %u", breq.count);
GST_LOG_OBJECT (pool, " type: %d", breq.type);
GST_LOG_OBJECT (pool, " memory: %d", breq.memory);
if (breq.count < GST_V4L2_MIN_BUFFERS)
goto no_buffers;
if (num_buffers != breq.count) {
GST_WARNING_OBJECT (pool, "using %u buffers instead", breq.count);
num_buffers = breq.count;
}
/* update min buffers with the amount of buffers we just reserved. We need
* to configure this value in the bufferpool so that the default start
* implementation calls our allocate function */
min_buffers = breq.count;
if (max_buffers == 0 || num_buffers < max_buffers) {
/* if we are asked to provide more buffers than we have allocated, start
* copying buffers when we only have 2 buffers left in the pool */
copy_threshold = 2;
} else {
/* we are certain that we have enough buffers so we don't need to
* copy */
copy_threshold = 0;
}
break;
}
case GST_V4L2_IO_USERPTR:
default:
num_buffers = 0;
copy_threshold = 0;
g_assert_not_reached ();
break;
}
pool->size = size;
pool->num_buffers = num_buffers;
pool->copy_threshold = copy_threshold;
if (obj->mode == GST_V4L2_IO_DMABUF)
allocator = gst_dmabuf_allocator_new ();
if (pool->allocator)
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gst_object_unref (pool->allocator);
if ((pool->allocator = allocator))
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gst_object_ref (allocator);
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pool->params = params;
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gst_buffer_pool_config_set_params (config, caps, size, min_buffers,
max_buffers);
return GST_BUFFER_POOL_CLASS (parent_class)->set_config (bpool, config);
/* ERRORS */
missing_video_api:
{
GST_ERROR_OBJECT (pool, "missing GstMetaVideo API in config, "
"default stride: %d, wanted stride %u",
GST_VIDEO_INFO_PLANE_STRIDE (&obj->info, 0), obj->bytesperline);
return FALSE;
}
wrong_config:
{
GST_ERROR_OBJECT (pool, "invalid config %" GST_PTR_FORMAT, config);
return FALSE;
}
reqbufs_failed:
{
GST_ERROR_OBJECT (pool,
"error requesting %d buffers: %s", num_buffers, g_strerror (errno));
return FALSE;
}
no_buffers:
{
GST_ERROR_OBJECT (pool,
"we received %d from device '%s', we want at least %d",
breq.count, obj->videodev, GST_V4L2_MIN_BUFFERS);
return FALSE;
}
}
static gboolean
start_streaming (GstV4l2BufferPool * pool)
{
GstV4l2Object *obj = pool->obj;
switch (obj->mode) {
case GST_V4L2_IO_RW:
break;
case GST_V4L2_IO_MMAP:
case GST_V4L2_IO_USERPTR:
case GST_V4L2_IO_DMABUF:
GST_DEBUG_OBJECT (pool, "STREAMON");
if (v4l2_ioctl (pool->video_fd, VIDIOC_STREAMON, &obj->type) < 0)
goto start_failed;
break;
default:
g_assert_not_reached ();
break;
}
pool->streaming = TRUE;
return TRUE;
/* ERRORS */
start_failed:
{
GST_ERROR_OBJECT (pool, "error with STREAMON %d (%s)", errno,
g_strerror (errno));
return FALSE;
}
}
static gboolean
gst_v4l2_buffer_pool_start (GstBufferPool * bpool)
{
GstV4l2BufferPool *pool = GST_V4L2_BUFFER_POOL (bpool);
GstV4l2Object *obj = pool->obj;
pool->obj = obj;
pool->buffers = g_new0 (GstBuffer *, pool->num_buffers);
pool->num_allocated = 0;
/* now, allocate the buffers: */
if (!GST_BUFFER_POOL_CLASS (parent_class)->start (bpool))
goto start_failed;
/* we can start capturing now, we wait for the playback case until we queued
* the first buffer */
if (obj->type == V4L2_BUF_TYPE_VIDEO_CAPTURE)
if (!start_streaming (pool))
goto start_failed;
gst_poll_set_flushing (obj->poll, FALSE);
return TRUE;
/* ERRORS */
start_failed:
{
GST_ERROR_OBJECT (pool, "failed to start streaming");
return FALSE;
}
}
static void
gst_v4l2_buffer_pool_free_buffers (GstV4l2BufferPool * pool)
{
if (pool->num_buffers > 0) {
struct v4l2_requestbuffers breq;
memset (&breq, 0, sizeof (struct v4l2_requestbuffers));
breq.type = pool->obj->type;
breq.count = 0;
breq.memory = V4L2_MEMORY_MMAP;
if (v4l2_ioctl (pool->video_fd, VIDIOC_REQBUFS, &breq) < 0) {
GST_ERROR_OBJECT (pool, "error releasing buffers: %s",
g_strerror (errno));
}
pool->num_buffers = 0;
}
}
static gboolean
gst_v4l2_buffer_pool_stop (GstBufferPool * bpool)
{
gboolean ret;
GstV4l2BufferPool *pool = GST_V4L2_BUFFER_POOL (bpool);
GstV4l2Object *obj = pool->obj;
guint n;
GST_DEBUG_OBJECT (pool, "stopping pool");
gst_poll_set_flushing (obj->poll, TRUE);
if (pool->streaming) {
switch (obj->mode) {
case GST_V4L2_IO_RW:
break;
case GST_V4L2_IO_MMAP:
case GST_V4L2_IO_USERPTR:
case GST_V4L2_IO_DMABUF:
/* we actually need to sync on all queued buffers but not
* on the non-queued ones */
GST_DEBUG_OBJECT (pool, "STREAMOFF");
if (v4l2_ioctl (pool->video_fd, VIDIOC_STREAMOFF, &obj->type) < 0)
goto stop_failed;
break;
default:
g_assert_not_reached ();
break;
}
pool->streaming = FALSE;
}
/* first free the buffers in the queue */
ret = GST_BUFFER_POOL_CLASS (parent_class)->stop (bpool);
/* then free the remaining buffers */
for (n = 0; n < pool->num_buffers; n++) {
if (pool->buffers[n])
gst_v4l2_buffer_pool_free_buffer (bpool, pool->buffers[n]);
}
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pool->num_queued = 0;
g_free (pool->buffers);
pool->buffers = NULL;
gst_v4l2_buffer_pool_free_buffers (pool);
return ret;
/* ERRORS */
stop_failed:
{
GST_ERROR_OBJECT (pool, "error with STREAMOFF %d (%s)", errno,
g_strerror (errno));
return FALSE;
}
}
static GstFlowReturn
gst_v4l2_object_poll (GstV4l2Object * v4l2object)
{
gint ret;
if (v4l2object->can_poll_device) {
GST_LOG_OBJECT (v4l2object->element, "polling device");
ret = gst_poll_wait (v4l2object->poll, GST_CLOCK_TIME_NONE);
if (G_UNLIKELY (ret < 0)) {
if (errno == EBUSY)
goto stopped;
if (errno == ENXIO) {
GST_WARNING_OBJECT (v4l2object->element,
"v4l2 device doesn't support polling. Disabling");
v4l2object->can_poll_device = FALSE;
} else {
if (errno != EAGAIN && errno != EINTR)
goto select_error;
}
}
}
return GST_FLOW_OK;
/* ERRORS */
stopped:
{
GST_DEBUG ("stop called");
return GST_FLOW_FLUSHING;
}
select_error:
{
GST_ELEMENT_ERROR (v4l2object->element, RESOURCE, READ, (NULL),
("poll error %d: %s (%d)", ret, g_strerror (errno), errno));
return GST_FLOW_ERROR;
}
}
static GstFlowReturn
gst_v4l2_buffer_pool_qbuf (GstV4l2BufferPool * pool, GstBuffer * buf)
{
2011-10-31 01:24:04 +00:00
GstV4l2Meta *meta;
gint index;
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meta = GST_V4L2_META_GET (buf);
if (meta == NULL) {
GST_LOG_OBJECT (pool, "unref copied buffer %p", buf);
/* no meta, it was a copied buffer that we can unref */
gst_buffer_unref (buf);
return GST_FLOW_OK;
}
index = meta->vbuffer.index;
meta->vbuffer.bytesused = gst_buffer_get_size (buf);
GST_LOG_OBJECT (pool,
"enqueue buffer %p, index:%d, queued:%d, flags:%08x mem:%p used:%d",
buf, index, pool->num_queued, meta->vbuffer.flags,
meta->mem, meta->vbuffer.bytesused);
if (pool->buffers[index] != NULL)
goto already_queued;
GST_LOG_OBJECT (pool, "doing QBUF");
if (v4l2_ioctl (pool->video_fd, VIDIOC_QBUF, &meta->vbuffer) < 0)
goto queue_failed;
pool->buffers[index] = buf;
pool->num_queued++;
return GST_FLOW_OK;
/* ERRORS */
already_queued:
{
GST_WARNING_OBJECT (pool, "the buffer was already queued");
return GST_FLOW_ERROR;
}
queue_failed:
{
GST_WARNING_OBJECT (pool, "could not queue a buffer %d (%s)", errno,
g_strerror (errno));
return GST_FLOW_ERROR;
}
}
static GstFlowReturn
gst_v4l2_buffer_pool_dqbuf (GstV4l2BufferPool * pool, GstBuffer ** buffer)
{
GstFlowReturn res;
GstBuffer *outbuf;
struct v4l2_buffer vbuffer;
GstV4l2Object *obj = pool->obj;
GstClockTime timestamp;
GstV4l2Meta *meta;
if ((res = gst_v4l2_object_poll (obj)) != GST_FLOW_OK)
goto poll_error;
memset (&vbuffer, 0x00, sizeof (vbuffer));
vbuffer.type = obj->type;
#if HAVE_DECL_V4L2_MEMORY_DMABUF
if (obj->mode == GST_V4L2_IO_DMABUF)
vbuffer.memory = V4L2_MEMORY_DMABUF;
else
#endif
vbuffer.memory = V4L2_MEMORY_MMAP;
GST_LOG_OBJECT (pool, "doing DQBUF");
if (v4l2_ioctl (pool->video_fd, VIDIOC_DQBUF, &vbuffer) < 0)
goto error;
/* get our GstBuffer with that index from the pool, if the buffer was
* outstanding we have a serious problem.
*/
outbuf = pool->buffers[vbuffer.index];
if (outbuf == NULL)
goto no_buffer;
/* mark the buffer outstanding */
pool->buffers[vbuffer.index] = NULL;
pool->num_queued--;
timestamp = GST_TIMEVAL_TO_TIME (vbuffer.timestamp);
meta = GST_V4L2_META_GET (outbuf);
g_assert (meta != NULL);
GST_LOG_OBJECT (pool,
"dequeued buffer %p seq:%d (ix=%d), mem %p used %d, flags %08x, ts %"
GST_TIME_FORMAT ", pool-queued=%d, buffer=%p", outbuf, vbuffer.sequence,
vbuffer.index, meta->mem, vbuffer.bytesused, vbuffer.flags,
GST_TIME_ARGS (timestamp), pool->num_queued, outbuf);
/* set top/bottom field first if v4l2_buffer has the information */
2011-12-19 18:03:52 +00:00
if (vbuffer.field == V4L2_FIELD_INTERLACED_TB) {
2011-08-25 14:41:23 +00:00
GST_BUFFER_FLAG_SET (outbuf, GST_VIDEO_BUFFER_FLAG_TFF);
2011-12-19 18:03:52 +00:00
}
if (vbuffer.field == V4L2_FIELD_INTERLACED_BT) {
2011-08-25 14:41:23 +00:00
GST_BUFFER_FLAG_UNSET (outbuf, GST_VIDEO_BUFFER_FLAG_TFF);
2011-12-19 18:03:52 +00:00
}
/* The size can change at every frame, esp. with jpeg. The GstMemory
* inside the GstBuffer could have been changed by some other
* element, so just put back the original one. We always set it as
* no share, so if it's not there, it's not used at all.
*/
if (obj->type == V4L2_BUF_TYPE_VIDEO_CAPTURE) {
gst_buffer_remove_all_memory (outbuf);
gst_buffer_append_memory (outbuf,
gst_memory_new_wrapped (GST_MEMORY_FLAG_NO_SHARE,
meta->mem, vbuffer.length, 0, vbuffer.bytesused, NULL, NULL));
}
GST_BUFFER_TIMESTAMP (outbuf) = timestamp;
*buffer = outbuf;
return GST_FLOW_OK;
/* ERRORS */
poll_error:
{
GST_DEBUG_OBJECT (pool, "poll error %s", gst_flow_get_name (res));
return res;
}
error:
{
GST_WARNING_OBJECT (pool,
"problem dequeuing frame %d (ix=%d), pool-ct=%d, buf.flags=%d",
vbuffer.sequence, vbuffer.index,
GST_MINI_OBJECT_REFCOUNT (pool), vbuffer.flags);
switch (errno) {
case EAGAIN:
GST_WARNING_OBJECT (pool,
"Non-blocking I/O has been selected using O_NONBLOCK and"
" no buffer was in the outgoing queue. device %s", obj->videodev);
break;
case EINVAL:
2011-07-15 10:00:54 +00:00
GST_ERROR_OBJECT (pool,
"The buffer type is not supported, or the index is out of bounds, "
"or no buffers have been allocated yet, or the userptr "
"or length are invalid. device %s", obj->videodev);
break;
case ENOMEM:
2011-07-15 10:00:54 +00:00
GST_ERROR_OBJECT (pool,
"insufficient memory to enqueue a user pointer buffer");
break;
case EIO:
GST_INFO_OBJECT (pool,
"VIDIOC_DQBUF failed due to an internal error."
" Can also indicate temporary problems like signal loss."
" Note the driver might dequeue an (empty) buffer despite"
" returning an error, or even stop capturing."
" device %s", obj->videodev);
/* have we de-queued a buffer ? */
if (!(vbuffer.flags & (V4L2_BUF_FLAG_QUEUED | V4L2_BUF_FLAG_DONE))) {
GST_DEBUG_OBJECT (pool, "reenqueing buffer");
/* FIXME ... should we do something here? */
}
break;
case EINTR:
GST_WARNING_OBJECT (pool,
"could not sync on a buffer on device %s", obj->videodev);
break;
default:
GST_WARNING_OBJECT (pool,
"Grabbing frame got interrupted on %s unexpectedly. %d: %s.",
obj->videodev, errno, g_strerror (errno));
break;
}
return GST_FLOW_ERROR;
}
no_buffer:
{
GST_ERROR_OBJECT (pool, "No free buffer found in the pool at index %d.",
2011-07-15 10:00:54 +00:00
vbuffer.index);
return GST_FLOW_ERROR;
}
}
static GstFlowReturn
gst_v4l2_buffer_pool_acquire_buffer (GstBufferPool * bpool, GstBuffer ** buffer,
2012-03-15 13:06:40 +00:00
GstBufferPoolAcquireParams * params)
{
GstFlowReturn ret;
GstV4l2BufferPool *pool = GST_V4L2_BUFFER_POOL (bpool);
GstV4l2Object *obj = pool->obj;
GST_DEBUG_OBJECT (pool, "acquire");
if (GST_BUFFER_POOL_IS_FLUSHING (bpool))
goto flushing;
switch (obj->type) {
case V4L2_BUF_TYPE_VIDEO_CAPTURE:
/* capture, This function should return a buffer with new captured data */
switch (obj->mode) {
case GST_V4L2_IO_RW:
/* take empty buffer from the pool */
ret = GST_BUFFER_POOL_CLASS (parent_class)->acquire_buffer (bpool,
buffer, params);
break;
case GST_V4L2_IO_DMABUF:
case GST_V4L2_IO_MMAP:
/* just dequeue a buffer, we basically use the queue of v4l2 as the
* storage for our buffers. This function does poll first so we can
* interrupt it fine. */
ret = gst_v4l2_buffer_pool_dqbuf (pool, buffer);
if (G_UNLIKELY (ret != GST_FLOW_OK))
goto done;
/* start copying buffers when we are running low on buffers */
if (pool->num_queued < pool->copy_threshold) {
GstBuffer *copy;
#ifdef VIDIOC_CREATE_BUFS
if (pool->can_alloc) {
if (GST_BUFFER_POOL_CLASS (parent_class)->acquire_buffer (bpool,
&copy, params) == GST_FLOW_OK) {
gst_v4l2_buffer_pool_release_buffer (bpool, copy);
break;
} else {
pool->can_alloc = FALSE;
}
}
#endif
/* copy the buffer */
copy = gst_buffer_copy_region (*buffer,
GST_BUFFER_COPY_ALL | GST_BUFFER_COPY_DEEP, 0, -1);
GST_LOG_OBJECT (pool, "copy buffer %p->%p", *buffer, copy);
/* and requeue so that we can continue capturing */
ret = gst_v4l2_buffer_pool_qbuf (pool, *buffer);
*buffer = copy;
}
break;
case GST_V4L2_IO_USERPTR:
default:
ret = GST_FLOW_ERROR;
g_assert_not_reached ();
break;
}
break;
case V4L2_BUF_TYPE_VIDEO_OUTPUT:
/* playback, This function should return an empty buffer */
switch (obj->mode) {
case GST_V4L2_IO_RW:
/* get an empty buffer */
ret = GST_BUFFER_POOL_CLASS (parent_class)->acquire_buffer (bpool,
buffer, params);
break;
case GST_V4L2_IO_MMAP:
/* get a free unqueued buffer */
ret = GST_BUFFER_POOL_CLASS (parent_class)->acquire_buffer (bpool,
buffer, params);
break;
case GST_V4L2_IO_USERPTR:
default:
ret = GST_FLOW_ERROR;
g_assert_not_reached ();
break;
}
break;
default:
ret = GST_FLOW_ERROR;
g_assert_not_reached ();
break;
}
done:
return ret;
/* ERRORS */
flushing:
{
GST_DEBUG_OBJECT (pool, "We are flushing");
return GST_FLOW_FLUSHING;
}
}
static void
gst_v4l2_buffer_pool_release_buffer (GstBufferPool * bpool, GstBuffer * buffer)
{
GstV4l2BufferPool *pool = GST_V4L2_BUFFER_POOL (bpool);
GstV4l2Object *obj = pool->obj;
GST_DEBUG_OBJECT (pool, "release buffer %p", buffer);
switch (obj->type) {
case V4L2_BUF_TYPE_VIDEO_CAPTURE:
/* capture, put the buffer back in the queue so that we can refill it
* later. */
switch (obj->mode) {
case GST_V4L2_IO_RW:
/* release back in the pool */
GST_BUFFER_POOL_CLASS (parent_class)->release_buffer (bpool, buffer);
break;
case GST_V4L2_IO_DMABUF:
case GST_V4L2_IO_MMAP:
/* queue back in the device */
gst_v4l2_buffer_pool_qbuf (pool, buffer);
break;
case GST_V4L2_IO_USERPTR:
default:
g_assert_not_reached ();
break;
}
break;
case V4L2_BUF_TYPE_VIDEO_OUTPUT:
switch (obj->mode) {
case GST_V4L2_IO_RW:
/* release back in the pool */
GST_BUFFER_POOL_CLASS (parent_class)->release_buffer (bpool, buffer);
break;
case GST_V4L2_IO_MMAP:
{
2011-10-31 01:24:04 +00:00
GstV4l2Meta *meta;
2013-04-03 09:09:37 +00:00
guint index;
2011-10-31 01:24:04 +00:00
meta = GST_V4L2_META_GET (buffer);
g_assert (meta != NULL);
2013-04-03 09:09:37 +00:00
index = meta->vbuffer.index;
if (pool->buffers[index] == NULL) {
GST_LOG_OBJECT (pool, "buffer %u not queued, putting on free list",
index);
/* reset to the full length, in case it was changed */
gst_buffer_resize (buffer, 0, meta->vbuffer.length);
/* playback, put the buffer back in the queue to refill later. */
GST_BUFFER_POOL_CLASS (parent_class)->release_buffer (bpool,
buffer);
} else {
/* the buffer is queued in the device but maybe not played yet. We just
* leave it there and not make it available for future calls to acquire
* for now. The buffer will be dequeued and reused later. */
2013-04-03 09:09:37 +00:00
GST_LOG_OBJECT (pool, "buffer %u is queued", index);
}
break;
}
case GST_V4L2_IO_USERPTR:
default:
g_assert_not_reached ();
break;
}
break;
default:
g_assert_not_reached ();
break;
}
}
static void
gst_v4l2_buffer_pool_finalize (GObject * object)
{
GstV4l2BufferPool *pool = GST_V4L2_BUFFER_POOL (object);
gst_v4l2_buffer_pool_free_buffers (pool);
if (pool->video_fd >= 0)
v4l2_close (pool->video_fd);
if (pool->allocator)
2012-07-09 14:27:10 +00:00
gst_object_unref (pool->allocator);
g_free (pool->buffers);
gst_object_unref (pool->obj->element);
G_OBJECT_CLASS (parent_class)->finalize (object);
}
static void
gst_v4l2_buffer_pool_init (GstV4l2BufferPool * pool)
{
}
static void
gst_v4l2_buffer_pool_class_init (GstV4l2BufferPoolClass * klass)
{
GObjectClass *object_class = G_OBJECT_CLASS (klass);
GstBufferPoolClass *bufferpool_class = GST_BUFFER_POOL_CLASS (klass);
object_class->finalize = gst_v4l2_buffer_pool_finalize;
bufferpool_class->start = gst_v4l2_buffer_pool_start;
bufferpool_class->stop = gst_v4l2_buffer_pool_stop;
bufferpool_class->set_config = gst_v4l2_buffer_pool_set_config;
bufferpool_class->alloc_buffer = gst_v4l2_buffer_pool_alloc_buffer;
bufferpool_class->acquire_buffer = gst_v4l2_buffer_pool_acquire_buffer;
bufferpool_class->release_buffer = gst_v4l2_buffer_pool_release_buffer;
bufferpool_class->free_buffer = gst_v4l2_buffer_pool_free_buffer;
}
/**
* gst_v4l2_buffer_pool_new:
* @obj: the v4l2 object owning the pool
*
* Construct a new buffer pool.
*
* Returns: the new pool, use gst_object_unref() to free resources
*/
GstBufferPool *
gst_v4l2_buffer_pool_new (GstV4l2Object * obj, GstCaps * caps)
{
GstV4l2BufferPool *pool;
GstStructure *s;
2011-07-18 08:51:21 +00:00
gint fd;
2011-07-18 08:51:21 +00:00
fd = v4l2_dup (obj->video_fd);
if (fd < 0)
goto dup_failed;
2011-07-18 08:51:21 +00:00
pool = (GstV4l2BufferPool *) g_object_new (GST_TYPE_V4L2_BUFFER_POOL, NULL);
pool->video_fd = fd;
pool->obj = obj;
pool->can_alloc = TRUE;
s = gst_buffer_pool_get_config (GST_BUFFER_POOL_CAST (pool));
2012-03-15 21:11:17 +00:00
gst_buffer_pool_config_set_params (s, caps, obj->sizeimage, 2, 0);
gst_buffer_pool_set_config (GST_BUFFER_POOL_CAST (pool), s);
gst_object_ref (obj->element);
return GST_BUFFER_POOL (pool);
/* ERRORS */
dup_failed:
{
2011-07-18 08:51:21 +00:00
GST_DEBUG ("failed to dup fd %d (%s)", errno, g_strerror (errno));
return NULL;
}
}
static GstFlowReturn
gst_v4l2_do_read (GstV4l2BufferPool * pool, GstBuffer * buf)
{
GstFlowReturn res;
GstV4l2Object *obj = pool->obj;
gint amount;
2012-01-24 13:38:58 +00:00
GstMapInfo map;
gint toread;
toread = obj->sizeimage;
GST_LOG_OBJECT (pool, "reading %d bytes into buffer %p", toread, buf);
2012-01-24 13:38:58 +00:00
gst_buffer_map (buf, &map, GST_MAP_WRITE);
do {
if ((res = gst_v4l2_object_poll (obj)) != GST_FLOW_OK)
goto poll_error;
2012-01-24 13:38:58 +00:00
amount = v4l2_read (obj->video_fd, map.data, toread);
if (amount == toread) {
break;
} else if (amount == -1) {
if (errno == EAGAIN || errno == EINTR) {
continue;
} else
goto read_error;
} else {
/* short reads can happen if a signal interrupts the read */
continue;
}
} while (TRUE);
GST_LOG_OBJECT (pool, "read %d bytes", amount);
2012-01-24 13:38:58 +00:00
gst_buffer_unmap (buf, &map);
gst_buffer_resize (buf, 0, amount);
return GST_FLOW_OK;
/* ERRORS */
poll_error:
{
GST_DEBUG ("poll error %s", gst_flow_get_name (res));
goto cleanup;
}
read_error:
{
GST_ELEMENT_ERROR (obj->element, RESOURCE, READ,
(_("Error reading %d bytes from device '%s'."),
toread, obj->videodev), GST_ERROR_SYSTEM);
res = GST_FLOW_ERROR;
goto cleanup;
}
cleanup:
{
2012-01-24 13:38:58 +00:00
gst_buffer_unmap (buf, &map);
gst_buffer_resize (buf, 0, 0);
return res;
}
}
/**
* gst_v4l2_buffer_pool_process:
* @bpool: a #GstBufferPool
* @buf: a #GstBuffer
*
* Process @buf in @bpool. For capture devices, this functions fills @buf with
* data from the device. For output devices, this functions send the contents of
* @buf to the device for playback.
*
* Returns: %GST_FLOW_OK on success.
*/
GstFlowReturn
gst_v4l2_buffer_pool_process (GstV4l2BufferPool * pool, GstBuffer * buf)
{
GstFlowReturn ret = GST_FLOW_OK;
GstBufferPool *bpool = GST_BUFFER_POOL_CAST (pool);
GstV4l2Object *obj = pool->obj;
GST_DEBUG_OBJECT (pool, "process buffer %p", buf);
switch (obj->type) {
case V4L2_BUF_TYPE_VIDEO_CAPTURE:
/* capture */
switch (obj->mode) {
case GST_V4L2_IO_RW:
/* capture into the buffer */
ret = gst_v4l2_do_read (pool, buf);
break;
case GST_V4L2_IO_MMAP:
{
GstBuffer *tmp;
if (buf->pool == bpool)
/* nothing, data was inside the buffer when we did _acquire() */
goto done;
/* buffer not from our pool, grab a frame and copy it into the target */
if ((ret = gst_v4l2_buffer_pool_dqbuf (pool, &tmp)) != GST_FLOW_OK)
goto done;
if (!gst_v4l2_object_copy (obj, buf, tmp))
goto copy_failed;
/* an queue the buffer again after the copy */
if ((ret = gst_v4l2_buffer_pool_qbuf (pool, tmp)) != GST_FLOW_OK)
goto done;
break;
}
case GST_V4L2_IO_USERPTR:
default:
g_assert_not_reached ();
break;
}
break;
case V4L2_BUF_TYPE_VIDEO_OUTPUT:
/* playback */
switch (obj->mode) {
case GST_V4L2_IO_RW:
/* FIXME, do write() */
GST_WARNING_OBJECT (pool, "implement write()");
break;
case GST_V4L2_IO_DMABUF:
case GST_V4L2_IO_MMAP:
{
GstBuffer *to_queue;
if (buf->pool == bpool) {
/* nothing, we can queue directly */
to_queue = gst_buffer_ref (buf);
GST_LOG_OBJECT (pool, "processing buffer from our pool");
} else {
GST_LOG_OBJECT (pool, "alloc buffer from our pool");
if (!gst_buffer_pool_is_active (bpool)) {
GstStructure *config;
/* this pool was not activated, configure and activate */
GST_DEBUG_OBJECT (pool, "activating pool");
config = gst_buffer_pool_get_config (bpool);
gst_buffer_pool_config_add_option (config,
2011-10-31 01:24:04 +00:00
GST_BUFFER_POOL_OPTION_VIDEO_META);
gst_buffer_pool_set_config (bpool, config);
if (!gst_buffer_pool_set_active (bpool, TRUE))
goto activate_failed;
}
/* this can block if all buffers are outstanding which would be
* strange because we would expect the upstream element to have
* allocated them and returned to us.. */
ret = gst_buffer_pool_acquire_buffer (bpool, &to_queue, NULL);
if (ret != GST_FLOW_OK)
goto acquire_failed;
/* copy into it and queue */
if (!gst_v4l2_object_copy (obj, to_queue, buf))
goto copy_failed;
}
if ((ret = gst_v4l2_buffer_pool_qbuf (pool, to_queue)) != GST_FLOW_OK)
goto done;
/* if we are not streaming yet (this is the first buffer, start
* streaming now */
if (!pool->streaming)
if (!start_streaming (pool))
goto start_failed;
if (pool->num_queued == pool->num_allocated) {
v4l2: rework sink buffer refcounting This is a followup patch for #700781, which is not quite correct. The buffer handling is quite complicated here. The original code intended to the the following: - gst_v4l2_buffer_pool_process() calls QBUF and adds the buffer to the local list. - The sink calls gst_buffer_unref() which returns the buffer to the pool but not the 'free list'. - Some time later DQBUF returns the buffer and gst_v4l2_buffer_pool_release_buffer() puts in on the 'free list'. If the buffer must be copied then (parent_class)->acquire_buffer() is called directly to keep the buffer in the pool. This has two problems: 1. If gst_v4l2_buffer_pool_release_buffer() is called before the buffer is returned to the pool, then the buffer is put on the 'free list' twice. This can happen if a reference to the buffer is kept outside the sink, of if DQBUF returns the buffer, that was just queued with QBUF. 2. If buffers are copied, then all buffers are in the pool at all times. As a result gst_v4l2_buffer_pool_stop() and gst_v4l2_buffer_pool_dqbuf() can access pool->buffers at the same time, which can lead to memory corruption. The patch for #700781 fixes those problems, but with the side effect that there are always buffers outside the pool (because they are queued) and the pool is never stopped. This patch fixes this by releasing the reference to the buffer after handling it (to avoid problem 2.) so it can be returned to the pool. gst_v4l2_buffer_pool_release_buffer() is only called if the buffer is already in the pool (to avoid problem 1.). Fixes https://bugzilla.gnome.org/show_bug.cgi?id=701375
2013-05-28 17:14:15 +00:00
GstBuffer *out;
/* all buffers are queued, try to dequeue one and release it back
* into the pool so that _acquire can get to it again. */
v4l2: rework sink buffer refcounting This is a followup patch for #700781, which is not quite correct. The buffer handling is quite complicated here. The original code intended to the the following: - gst_v4l2_buffer_pool_process() calls QBUF and adds the buffer to the local list. - The sink calls gst_buffer_unref() which returns the buffer to the pool but not the 'free list'. - Some time later DQBUF returns the buffer and gst_v4l2_buffer_pool_release_buffer() puts in on the 'free list'. If the buffer must be copied then (parent_class)->acquire_buffer() is called directly to keep the buffer in the pool. This has two problems: 1. If gst_v4l2_buffer_pool_release_buffer() is called before the buffer is returned to the pool, then the buffer is put on the 'free list' twice. This can happen if a reference to the buffer is kept outside the sink, of if DQBUF returns the buffer, that was just queued with QBUF. 2. If buffers are copied, then all buffers are in the pool at all times. As a result gst_v4l2_buffer_pool_stop() and gst_v4l2_buffer_pool_dqbuf() can access pool->buffers at the same time, which can lead to memory corruption. The patch for #700781 fixes those problems, but with the side effect that there are always buffers outside the pool (because they are queued) and the pool is never stopped. This patch fixes this by releasing the reference to the buffer after handling it (to avoid problem 2.) so it can be returned to the pool. gst_v4l2_buffer_pool_release_buffer() is only called if the buffer is already in the pool (to avoid problem 1.). Fixes https://bugzilla.gnome.org/show_bug.cgi?id=701375
2013-05-28 17:14:15 +00:00
ret = gst_v4l2_buffer_pool_dqbuf (pool, &out);
if (ret != GST_FLOW_OK) {
gst_buffer_unref (to_queue);
goto done;
}
/* release the rendered buffer back into the pool. This wakes up any
v4l2: rework sink buffer refcounting This is a followup patch for #700781, which is not quite correct. The buffer handling is quite complicated here. The original code intended to the the following: - gst_v4l2_buffer_pool_process() calls QBUF and adds the buffer to the local list. - The sink calls gst_buffer_unref() which returns the buffer to the pool but not the 'free list'. - Some time later DQBUF returns the buffer and gst_v4l2_buffer_pool_release_buffer() puts in on the 'free list'. If the buffer must be copied then (parent_class)->acquire_buffer() is called directly to keep the buffer in the pool. This has two problems: 1. If gst_v4l2_buffer_pool_release_buffer() is called before the buffer is returned to the pool, then the buffer is put on the 'free list' twice. This can happen if a reference to the buffer is kept outside the sink, of if DQBUF returns the buffer, that was just queued with QBUF. 2. If buffers are copied, then all buffers are in the pool at all times. As a result gst_v4l2_buffer_pool_stop() and gst_v4l2_buffer_pool_dqbuf() can access pool->buffers at the same time, which can lead to memory corruption. The patch for #700781 fixes those problems, but with the side effect that there are always buffers outside the pool (because they are queued) and the pool is never stopped. This patch fixes this by releasing the reference to the buffer after handling it (to avoid problem 2.) so it can be returned to the pool. gst_v4l2_buffer_pool_release_buffer() is only called if the buffer is already in the pool (to avoid problem 1.). Fixes https://bugzilla.gnome.org/show_bug.cgi?id=701375
2013-05-28 17:14:15 +00:00
* thread waiting for a buffer in _acquire(). If the buffer still has
* a pool then this will happen when the refcount reaches 0 */
if (!out->pool)
gst_v4l2_buffer_pool_release_buffer (bpool, out);
}
v4l2: rework sink buffer refcounting This is a followup patch for #700781, which is not quite correct. The buffer handling is quite complicated here. The original code intended to the the following: - gst_v4l2_buffer_pool_process() calls QBUF and adds the buffer to the local list. - The sink calls gst_buffer_unref() which returns the buffer to the pool but not the 'free list'. - Some time later DQBUF returns the buffer and gst_v4l2_buffer_pool_release_buffer() puts in on the 'free list'. If the buffer must be copied then (parent_class)->acquire_buffer() is called directly to keep the buffer in the pool. This has two problems: 1. If gst_v4l2_buffer_pool_release_buffer() is called before the buffer is returned to the pool, then the buffer is put on the 'free list' twice. This can happen if a reference to the buffer is kept outside the sink, of if DQBUF returns the buffer, that was just queued with QBUF. 2. If buffers are copied, then all buffers are in the pool at all times. As a result gst_v4l2_buffer_pool_stop() and gst_v4l2_buffer_pool_dqbuf() can access pool->buffers at the same time, which can lead to memory corruption. The patch for #700781 fixes those problems, but with the side effect that there are always buffers outside the pool (because they are queued) and the pool is never stopped. This patch fixes this by releasing the reference to the buffer after handling it (to avoid problem 2.) so it can be returned to the pool. gst_v4l2_buffer_pool_release_buffer() is only called if the buffer is already in the pool (to avoid problem 1.). Fixes https://bugzilla.gnome.org/show_bug.cgi?id=701375
2013-05-28 17:14:15 +00:00
gst_buffer_unref (to_queue);
break;
}
case GST_V4L2_IO_USERPTR:
default:
g_assert_not_reached ();
break;
}
break;
default:
g_assert_not_reached ();
break;
}
done:
return ret;
/* ERRORS */
activate_failed:
{
GST_ERROR_OBJECT (obj->element, "failed to activate pool");
return GST_FLOW_ERROR;
}
acquire_failed:
{
GST_WARNING_OBJECT (obj->element, "failed to acquire a buffer: %s",
gst_flow_get_name (ret));
return ret;
}
copy_failed:
{
GST_ERROR_OBJECT (obj->element, "failed to copy data");
return GST_FLOW_ERROR;
}
start_failed:
{
GST_ERROR_OBJECT (obj->element, "failed to start streaming");
return GST_FLOW_ERROR;
}
}