From 4cd9255f0a8a9e15d81561f00f02d275b5095f70 Mon Sep 17 00:00:00 2001 From: "Oleksij Rempel (Alexey Fisher)" Date: Thu, 1 Mar 2012 14:15:29 +0100 Subject: [PATCH] v4l2src: fix v4l2_munmap() for compressed formats Make sure we always call munmap() with the same size we called mmap() with before. Current v4l2src uses the same structure for VIDIOC_QUERYBUF, VIDIOC_QBUF and v4l2_munmap calls. The problem is that the video buffer size (length) may vary for compressed or emulated bufs. VIDIOC_QBUF will change it if we pass the pointer of a v4l2_buffer. This is why we should avoid using same variable for mmap and video buffers. https://bugzilla.gnome.org/show_bug.cgi?id=671126 --- sys/v4l2/gstv4l2bufferpool.c | 5 +++-- sys/v4l2/gstv4l2bufferpool.h | 3 +++ 2 files changed, 6 insertions(+), 2 deletions(-) diff --git a/sys/v4l2/gstv4l2bufferpool.c b/sys/v4l2/gstv4l2bufferpool.c index b81c6a4118..51419ff984 100644 --- a/sys/v4l2/gstv4l2bufferpool.c +++ b/sys/v4l2/gstv4l2bufferpool.c @@ -106,9 +106,9 @@ gst_v4l2_buffer_finalize (GstV4l2Buffer * buffer) if (!resuscitated) { GST_LOG_OBJECT (pool->v4l2elem, "buffer %p (data %p, len %u) not recovered, unmapping", - buffer, GST_BUFFER_DATA (buffer), buffer->vbuffer.length); + buffer, GST_BUFFER_DATA (buffer), buffer->mmap_length); gst_mini_object_unref (GST_MINI_OBJECT (pool)); - v4l2_munmap ((void *) GST_BUFFER_DATA (buffer), buffer->vbuffer.length); + v4l2_munmap ((void *) GST_BUFFER_DATA (buffer), buffer->mmap_length); GST_MINI_OBJECT_CLASS (v4l2buffer_parent_class)->finalize (GST_MINI_OBJECT (buffer)); @@ -183,6 +183,7 @@ gst_v4l2_buffer_new (GstV4l2BufferPool * pool, guint index, GstCaps * caps) GST_LOG_OBJECT (pool->v4l2elem, " length: %u", ret->vbuffer.length); GST_LOG_OBJECT (pool->v4l2elem, " input: %u", ret->vbuffer.input); + ret->mmap_length = ret->vbuffer.length; data = (guint8 *) v4l2_mmap (0, ret->vbuffer.length, PROT_READ | PROT_WRITE, MAP_SHARED, pool->video_fd, ret->vbuffer.m.offset); diff --git a/sys/v4l2/gstv4l2bufferpool.h b/sys/v4l2/gstv4l2bufferpool.h index caad9ac2fc..36ea3233a6 100644 --- a/sys/v4l2/gstv4l2bufferpool.h +++ b/sys/v4l2/gstv4l2bufferpool.h @@ -70,6 +70,9 @@ struct _GstV4l2Buffer { GstBuffer buffer; struct v4l2_buffer vbuffer; + /* warning: the size of mmap buffer and + * the actual frame-buffer can be different. */ + size_t mmap_length; /* FIXME: have GstV4l2Src* instead, as this has GstV4l2BufferPool* */ /* FIXME: do we really want to fix this if GstV4l2Buffer/Pool is shared