[PATCH for 3.13] vb2: regression fix: always set length field.

[PATCH for 3.13] vb2: regression fix: always set length field.

[Hans Verkuil]

Commit dc77523c5da5513df1bbc74db2a522a94f4cec0e ensured that m.offset is
only set for the MMAP memory mode by calling __setup_offsets only for that
mode.

However, __setup_offsets also initializes the length fields, and that should
be done regardless of the memory mode. Because of that change the v4l2-ctl
test application fails for the USERPTR mode.

This fix creates a __setup_lengths function that sets the length, and
__setup_offsets just sets the offset and no longer touches the length.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
---
 drivers/media/v4l2-core/videobuf2-core.c | 21 ++++++++++++++++++++-
 1 file changed, 20 insertions(+), 1 deletion(-)

diff --git a/drivers/media/v4l2-core/videobuf2-core.c b/drivers/media/v4l2-core/videobuf2-core.c
index 57ba131..0edc165 100644
--- a/drivers/media/v4l2-core/videobuf2-core.c
+++ b/drivers/media/v4l2-core/videobuf2-core.c
@@ -145,6 +145,25 @@ static void __vb2_buf_dmabuf_put(struct vb2_buffer *vb)
 }
 
 /**
+ * __setup_lengths() - setup initial lengths for every plane in
+ * every buffer on the queue
+ */
+static void __setup_lengths(struct vb2_queue *q, unsigned int n)
+{
+	unsigned int buffer, plane;
+	struct vb2_buffer *vb;
+
+	for (buffer = q->num_buffers; buffer < q->num_buffers + n; ++buffer) {
+		vb = q->bufs[buffer];
+		if (!vb)
+			continue;
+
+		for (plane = 0; plane < vb->num_planes; ++plane)
+			vb->v4l2_planes[plane].length = q->plane_sizes[plane];
+	}
+}
+
+/**
  * __setup_offsets() - setup unique offsets ("cookies") for every plane in
  * every buffer on the queue
  */
@@ -169,7 +188,6 @@ static void __setup_offsets(struct vb2_queue *q, unsigned int n)
 			continue;
 
 		for (plane = 0; plane < vb->num_planes; ++plane) {
-			vb->v4l2_planes[plane].length = q->plane_sizes[plane];
 			vb->v4l2_planes[plane].m.mem_offset = off;
 
 			dprintk(3, "Buffer %d, plane %d offset 0x%08lx\n",
@@ -241,6 +259,7 @@ static int __vb2_queue_alloc(struct vb2_queue *q, enum v4l2_memory memory,
 		q->bufs[q->num_buffers + buffer] = vb;
 	}
 
+	__setup_lengths(q, buffer);
 	if (memory == V4L2_MEMORY_MMAP)
 		__setup_offsets(q, buffer);
 
-- 
1.8.4.rc3

Re: [PATCH for 3.13] vb2: regression fix: always set length field.

[Marek Szyprowski]

Hello,

On 2013-12-04 15:14, Hans Verkuil wrote:
> Commit dc77523c5da5513df1bbc74db2a522a94f4cec0e ensured that m.offset is
> only set for the MMAP memory mode by calling __setup_offsets only for that
> mode.
>
> However, __setup_offsets also initializes the length fields, and that should
> be done regardless of the memory mode. Because of that change the v4l2-ctl
> test application fails for the USERPTR mode.
>
> This fix creates a __setup_lengths function that sets the length, and
> __setup_offsets just sets the offset and no longer touches the length.
>
> Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>

Acked-by: Marek Szyprowski <m.szyprowski@samsung.com>

> ---
>   drivers/media/v4l2-core/videobuf2-core.c | 21 ++++++++++++++++++++-
>   1 file changed, 20 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/media/v4l2-core/videobuf2-core.c b/drivers/media/v4l2-core/videobuf2-core.c
> index 57ba131..0edc165 100644
> --- a/drivers/media/v4l2-core/videobuf2-core.c
> +++ b/drivers/media/v4l2-core/videobuf2-core.c
> @@ -145,6 +145,25 @@ static void __vb2_buf_dmabuf_put(struct vb2_buffer *vb)
>   }
>   
>   /**
> + * __setup_lengths() - setup initial lengths for every plane in
> + * every buffer on the queue
> + */
> +static void __setup_lengths(struct vb2_queue *q, unsigned int n)
> +{
> +	unsigned int buffer, plane;
> +	struct vb2_buffer *vb;
> +
> +	for (buffer = q->num_buffers; buffer < q->num_buffers + n; ++buffer) {
> +		vb = q->bufs[buffer];
> +		if (!vb)
> +			continue;
> +
> +		for (plane = 0; plane < vb->num_planes; ++plane)
> +			vb->v4l2_planes[plane].length = q->plane_sizes[plane];
> +	}
> +}
> +
> +/**
>    * __setup_offsets() - setup unique offsets ("cookies") for every plane in
>    * every buffer on the queue
>    */
> @@ -169,7 +188,6 @@ static void __setup_offsets(struct vb2_queue *q, unsigned int n)
>   			continue;
>   
>   		for (plane = 0; plane < vb->num_planes; ++plane) {
> -			vb->v4l2_planes[plane].length = q->plane_sizes[plane];
>   			vb->v4l2_planes[plane].m.mem_offset = off;
>   
>   			dprintk(3, "Buffer %d, plane %d offset 0x%08lx\n",
> @@ -241,6 +259,7 @@ static int __vb2_queue_alloc(struct vb2_queue *q, enum v4l2_memory memory,
>   		q->bufs[q->num_buffers + buffer] = vb;
>   	}
>   
> +	__setup_lengths(q, buffer);
>   	if (memory == V4L2_MEMORY_MMAP)
>   		__setup_offsets(q, buffer);
>   

Best regards
-- 
Marek Szyprowski, PhD
Samsung R&D Institute Poland