Re: [PATCH 04/10] [media] s5p-mfc: Don't allocate codec buffers on STREAMON.

From: Nicolas Dufresne <nicolas.dufresne@collabora.com>
To: Arun Kumar K <arun.kk@samsung.com>
Cc: linux-media@vger.kernel.org, linux-samsung-soc@vger.kernel.org,
	k.debski@samsung.com, posciak@chromium.org,
	avnd.kiran@samsung.com, arunkk.samsung@gmail.com
Subject: Re: [PATCH 04/10] [media] s5p-mfc: Don't allocate codec buffers on STREAMON.
Date: Fri, 25 Jul 2014 12:03:29 -0400	[thread overview]
Message-ID: <1406304209.2465.5.camel@mpb-nicolas> (raw)
In-Reply-To: <1400502786-4826-5-git-send-email-arun.kk@samsung.com>

Le lundi 19 mai 2014 à 18:03 +0530, Arun Kumar K a écrit :
> From: Pawel Osciak <posciak@chromium.org>
> 
> Currently, we allocate private codec buffers on STREAMON, which may fail
> if we are out of memory. We don't check for failure though, which will
> make us crash with the codec accessing random memory.
> 
> We shouldn't be failing STREAMON with out of memory errors though. So move
> the allocation of private codec buffers to REQBUFS for OUTPUT queue. Also,
> move MFC instance opening and closing to REQBUFS as well, as it's tied to
> allocation and deallocation of private codec buffers.
> 
> Signed-off-by: Pawel Osciak <posciak@chromium.org>
> Signed-off-by: Arun Kumar K <arun.kk@samsung.com>
> ---
>  drivers/media/platform/s5p-mfc/s5p_mfc.c      |    8 +++----
>  drivers/media/platform/s5p-mfc/s5p_mfc_ctrl.c |    1 +
>  drivers/media/platform/s5p-mfc/s5p_mfc_dec.c  |   30 +++++++++++--------------
>  3 files changed, 18 insertions(+), 21 deletions(-)
> 
> diff --git a/drivers/media/platform/s5p-mfc/s5p_mfc.c b/drivers/media/platform/s5p-mfc/s5p_mfc.c
> index 861087c..70f728f 100644
> --- a/drivers/media/platform/s5p-mfc/s5p_mfc.c
> +++ b/drivers/media/platform/s5p-mfc/s5p_mfc.c
> @@ -643,6 +643,7 @@ static irqreturn_t s5p_mfc_irq(int irq, void *priv)
>  
>  	case S5P_MFC_R2H_CMD_CLOSE_INSTANCE_RET:
>  		clear_work_bit(ctx);
> +		ctx->inst_no = MFC_NO_INSTANCE_SET;
>  		ctx->state = MFCINST_FREE;
>  		wake_up(&ctx->queue);
>  		goto irq_cleanup_hw;
> @@ -763,7 +764,7 @@ static int s5p_mfc_open(struct file *file)
>  		goto err_bad_node;
>  	}
>  	ctx->fh.ctrl_handler = &ctx->ctrl_handler;
> -	ctx->inst_no = -1;
> +	ctx->inst_no = MFC_NO_INSTANCE_SET;
>  	/* Load firmware if this is the first instance */
>  	if (dev->num_inst == 1) {
>  		dev->watchdog_timer.expires = jiffies +
> @@ -873,12 +874,11 @@ static int s5p_mfc_release(struct file *file)
>  	vb2_queue_release(&ctx->vq_dst);
>  	/* Mark context as idle */
>  	clear_work_bit_irqsave(ctx);
> -	/* If instance was initialised then
> +	/* If instance was initialised and not yet freed,
>  	 * return instance and free resources */
> -	if (ctx->inst_no != MFC_NO_INSTANCE_SET) {
> +	if (ctx->state != MFCINST_FREE && ctx->state != MFCINST_INIT) {
>  		mfc_debug(2, "Has to free instance\n");
>  		s5p_mfc_close_mfc_inst(dev, ctx);
> -		ctx->inst_no = MFC_NO_INSTANCE_SET;
>  	}
>  	/* hardware locking scheme */
>  	if (dev->curr_ctx == ctx->num)
> diff --git a/drivers/media/platform/s5p-mfc/s5p_mfc_ctrl.c b/drivers/media/platform/s5p-mfc/s5p_mfc_ctrl.c
> index 6f6e50a..6c3f8f7 100644
> --- a/drivers/media/platform/s5p-mfc/s5p_mfc_ctrl.c
> +++ b/drivers/media/platform/s5p-mfc/s5p_mfc_ctrl.c
> @@ -459,5 +459,6 @@ void s5p_mfc_close_mfc_inst(struct s5p_mfc_dev *dev, struct s5p_mfc_ctx *ctx)
>  	if (ctx->type == MFCINST_DECODER)
>  		s5p_mfc_hw_call(dev->mfc_ops, release_dec_desc_buffer, ctx);
>  
> +	ctx->inst_no = MFC_NO_INSTANCE_SET;
>  	ctx->state = MFCINST_FREE;
>  }
> diff --git a/drivers/media/platform/s5p-mfc/s5p_mfc_dec.c b/drivers/media/platform/s5p-mfc/s5p_mfc_dec.c
> index 995cee2..a4e6668 100644
> --- a/drivers/media/platform/s5p-mfc/s5p_mfc_dec.c
> +++ b/drivers/media/platform/s5p-mfc/s5p_mfc_dec.c
> @@ -475,11 +475,11 @@ static int reqbufs_output(struct s5p_mfc_dev *dev, struct s5p_mfc_ctx *ctx,
>  		ret = vb2_reqbufs(&ctx->vq_src, reqbufs);
>  		if (ret)
>  			goto out;
> +		s5p_mfc_close_mfc_inst(dev, ctx);

This so far seems to prevent us from probing memory type support. We
Initially call reqbufs(count = 0) for this, but this calls seems to
triggers a firmware error later if we do so. Any advise ?

>  		ctx->src_bufs_cnt = 0;
> +		ctx->output_state = QUEUE_FREE;
>  	} else if (ctx->output_state == QUEUE_FREE) {
> -		/* Can only request buffers after the instance
> -		 * has been opened.
> -		 */
> +		/* Can only request buffers when we have a valid format set. */
>  		WARN_ON(ctx->src_bufs_cnt != 0);
>  		if (ctx->state != MFCINST_INIT) {
>  			mfc_err("Reqbufs called in an invalid state\n");
> @@ -493,6 +493,13 @@ static int reqbufs_output(struct s5p_mfc_dev *dev, struct s5p_mfc_ctx *ctx,
>  		if (ret)
>  			goto out;
>  
> +		ret = s5p_mfc_open_mfc_inst(dev, ctx);
> +		if (ret) {
> +			reqbufs->count = 0;
> +			vb2_reqbufs(&ctx->vq_src, reqbufs);
> +			goto out;
> +		}
> +
>  		ctx->output_state = QUEUE_BUFS_REQUESTED;
>  	} else {
>  		mfc_err("Buffers have already been requested\n");
> @@ -594,7 +601,7 @@ static int vidioc_querybuf(struct file *file, void *priv,
>  		return -EINVAL;
>  	}
>  	mfc_debug(2, "State: %d, buf->type: %d\n", ctx->state, buf->type);
> -	if (ctx->state == MFCINST_INIT &&
> +	if (ctx->state == MFCINST_GOT_INST &&
>  			buf->type == V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE) {
>  		ret = vb2_querybuf(&ctx->vq_src, buf);
>  	} else if (ctx->state == MFCINST_RUNNING &&
> @@ -670,24 +677,13 @@ static int vidioc_streamon(struct file *file, void *priv,
>  			   enum v4l2_buf_type type)
>  {
>  	struct s5p_mfc_ctx *ctx = fh_to_ctx(priv);
> -	struct s5p_mfc_dev *dev = ctx->dev;
>  	int ret = -EINVAL;
>  
>  	mfc_debug_enter();
> -	if (type == V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE) {
> -		if (ctx->state == MFCINST_INIT) {
> -			ctx->dst_bufs_cnt = 0;
> -			ctx->src_bufs_cnt = 0;
> -			ctx->capture_state = QUEUE_FREE;
> -			ctx->output_state = QUEUE_FREE;
> -			ret = s5p_mfc_open_mfc_inst(dev, ctx);
> -			if (ret)
> -				return ret;
> -		}
> +	if (type == V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE)
>  		ret = vb2_streamon(&ctx->vq_src, type);
> -	} else if (type == V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE) {
> +	else if (type == V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE)
>  		ret = vb2_streamon(&ctx->vq_dst, type);
> -	}
>  	mfc_debug_leave();
>  	return ret;
>  }