From 6947756dfcecc493062a46e77f6bf51dddb5be75 Mon Sep 17 00:00:00 2001 From: Laurent Pinchart Date: Sun, 21 Nov 2010 13:36:34 -0300 Subject: [media] uvcvideo: Lock stream mutex when accessing format-related information The stream mutex protects access to the struct uvc_streaming ctrl, cur_format and cur_frame fields as well as to the hardware probe control. Lock it appropriately. Signed-off-by: Laurent Pinchart Signed-off-by: Mauro Carvalho Chehab --- drivers/media/video/uvc/uvc_v4l2.c | 78 +++++++++++++++++++++++++++----------- 1 file changed, 55 insertions(+), 23 deletions(-) (limited to 'drivers/media/video/uvc/uvc_v4l2.c') diff --git a/drivers/media/video/uvc/uvc_v4l2.c b/drivers/media/video/uvc/uvc_v4l2.c index 07dd2357fbb9..2f6dc6b97348 100644 --- a/drivers/media/video/uvc/uvc_v4l2.c +++ b/drivers/media/video/uvc/uvc_v4l2.c @@ -226,12 +226,14 @@ static int uvc_v4l2_try_format(struct uvc_streaming *stream, * developers test their webcams with the Linux driver as well as with * the Windows driver). */ + mutex_lock(&stream->mutex); if (stream->dev->quirks & UVC_QUIRK_PROBE_EXTRAFIELDS) probe->dwMaxVideoFrameSize = stream->ctrl.dwMaxVideoFrameSize; /* Probe the device. */ ret = uvc_probe_video(stream, probe); + mutex_unlock(&stream->mutex); if (ret < 0) goto done; @@ -255,14 +257,21 @@ done: static int uvc_v4l2_get_format(struct uvc_streaming *stream, struct v4l2_format *fmt) { - struct uvc_format *format = stream->cur_format; - struct uvc_frame *frame = stream->cur_frame; + struct uvc_format *format; + struct uvc_frame *frame; + int ret = 0; if (fmt->type != stream->type) return -EINVAL; - if (format == NULL || frame == NULL) - return -EINVAL; + mutex_lock(&stream->mutex); + format = stream->cur_format; + frame = stream->cur_frame; + + if (format == NULL || frame == NULL) { + ret = -EINVAL; + goto done; + } fmt->fmt.pix.pixelformat = format->fcc; fmt->fmt.pix.width = frame->wWidth; @@ -273,7 +282,9 @@ static int uvc_v4l2_get_format(struct uvc_streaming *stream, fmt->fmt.pix.colorspace = format->colorspace; fmt->fmt.pix.priv = 0; - return 0; +done: + mutex_unlock(&stream->mutex); + return ret; } static int uvc_v4l2_set_format(struct uvc_streaming *stream, @@ -287,18 +298,24 @@ static int uvc_v4l2_set_format(struct uvc_streaming *stream, if (fmt->type != stream->type) return -EINVAL; - if (uvc_queue_allocated(&stream->queue)) - return -EBUSY; - ret = uvc_v4l2_try_format(stream, fmt, &probe, &format, &frame); if (ret < 0) return ret; + mutex_lock(&stream->mutex); + + if (uvc_queue_allocated(&stream->queue)) { + ret = -EBUSY; + goto done; + } + memcpy(&stream->ctrl, &probe, sizeof probe); stream->cur_format = format; stream->cur_frame = frame; - return 0; +done: + mutex_unlock(&stream->mutex); + return ret; } static int uvc_v4l2_get_streamparm(struct uvc_streaming *stream, @@ -309,7 +326,10 @@ static int uvc_v4l2_get_streamparm(struct uvc_streaming *stream, if (parm->type != stream->type) return -EINVAL; + mutex_lock(&stream->mutex); numerator = stream->ctrl.dwFrameInterval; + mutex_unlock(&stream->mutex); + denominator = 10000000; uvc_simplify_fraction(&numerator, &denominator, 8, 333); @@ -336,7 +356,6 @@ static int uvc_v4l2_get_streamparm(struct uvc_streaming *stream, static int uvc_v4l2_set_streamparm(struct uvc_streaming *stream, struct v4l2_streamparm *parm) { - struct uvc_frame *frame = stream->cur_frame; struct uvc_streaming_control probe; struct v4l2_fract timeperframe; uint32_t interval; @@ -345,28 +364,36 @@ static int uvc_v4l2_set_streamparm(struct uvc_streaming *stream, if (parm->type != stream->type) return -EINVAL; - if (uvc_queue_streaming(&stream->queue)) - return -EBUSY; - if (parm->type == V4L2_BUF_TYPE_VIDEO_CAPTURE) timeperframe = parm->parm.capture.timeperframe; else timeperframe = parm->parm.output.timeperframe; - memcpy(&probe, &stream->ctrl, sizeof probe); interval = uvc_fraction_to_interval(timeperframe.numerator, timeperframe.denominator); - uvc_trace(UVC_TRACE_FORMAT, "Setting frame interval to %u/%u (%u).\n", timeperframe.numerator, timeperframe.denominator, interval); - probe.dwFrameInterval = uvc_try_frame_interval(frame, interval); + + mutex_lock(&stream->mutex); + + if (uvc_queue_streaming(&stream->queue)) { + mutex_unlock(&stream->mutex); + return -EBUSY; + } + + memcpy(&probe, &stream->ctrl, sizeof probe); + probe.dwFrameInterval = + uvc_try_frame_interval(stream->cur_frame, interval); /* Probe the device with the new settings. */ ret = uvc_probe_video(stream, &probe); - if (ret < 0) + if (ret < 0) { + mutex_unlock(&stream->mutex); return ret; + } memcpy(&stream->ctrl, &probe, sizeof probe); + mutex_unlock(&stream->mutex); /* Return the actual frame period. */ timeperframe.numerator = probe.dwFrameInterval; @@ -869,15 +896,17 @@ static long uvc_v4l2_do_ioctl(struct file *file, unsigned int cmd, void *arg) case VIDIOC_CROPCAP: { struct v4l2_cropcap *ccap = arg; - struct uvc_frame *frame = stream->cur_frame; if (ccap->type != stream->type) return -EINVAL; ccap->bounds.left = 0; ccap->bounds.top = 0; - ccap->bounds.width = frame->wWidth; - ccap->bounds.height = frame->wHeight; + + mutex_lock(&stream->mutex); + ccap->bounds.width = stream->cur_frame->wWidth; + ccap->bounds.height = stream->cur_frame->wHeight; + mutex_unlock(&stream->mutex); ccap->defrect = ccap->bounds; @@ -894,8 +923,6 @@ static long uvc_v4l2_do_ioctl(struct file *file, unsigned int cmd, void *arg) case VIDIOC_REQBUFS: { struct v4l2_requestbuffers *rb = arg; - unsigned int bufsize = - stream->ctrl.dwMaxVideoFrameSize; if (rb->type != stream->type || rb->memory != V4L2_MEMORY_MMAP) @@ -904,7 +931,10 @@ static long uvc_v4l2_do_ioctl(struct file *file, unsigned int cmd, void *arg) if ((ret = uvc_acquire_privileges(handle)) < 0) return ret; - ret = uvc_alloc_buffers(&stream->queue, rb->count, bufsize); + mutex_lock(&stream->mutex); + ret = uvc_alloc_buffers(&stream->queue, rb->count, + stream->ctrl.dwMaxVideoFrameSize); + mutex_unlock(&stream->mutex); if (ret < 0) return ret; @@ -952,7 +982,9 @@ static long uvc_v4l2_do_ioctl(struct file *file, unsigned int cmd, void *arg) if (!uvc_has_privileges(handle)) return -EBUSY; + mutex_lock(&stream->mutex); ret = uvc_video_enable(stream, 1); + mutex_unlock(&stream->mutex); if (ret < 0) return ret; break; -- cgit v1.2.3