Commit 6e423b75 authored by Benjamin Gaignard's avatar Benjamin Gaignard Committed by Hans Verkuil
Browse files

media: core: Rework how create_buf index returned value is computed 



When REMOVE_BUFS will be introduced holes could created in bufs array.
To be able to reuse these unused indices reworking how create->index
is set is mandatory.
Let __vb2_queue_alloc() decide which first index is correct and
forward this to the caller.

Signed-off-by: default avatarBenjamin Gaignard <benjamin.gaignard@collabora.com>
Acked-by: default avatarMauro Carvalho Chehab <mchehab@kernel.org>
Signed-off-by: default avatarHans Verkuil <hverkuil-cisco@xs4all.nl>
parent f5131d5c

drivers/media/common/videobuf2/videobuf2-core.c

+13 −5
Original line number Diff line number Diff line
@@ -442,12 +442,15 @@ static void vb2_queue_remove_buffer(struct vb2_buffer *vb) 
 * __vb2_queue_alloc() - allocate vb2 buffer structures and (for MMAP type)

 * video buffer memory for all buffers/planes on the queue and initializes the

 * queue

 * @first_index: index of the first created buffer, all newly allocated buffers

 *		 have indices in the range [first_index..first_index+count-1]

 *

 * Returns the number of buffers successfully allocated.

 */

static int __vb2_queue_alloc(struct vb2_queue *q, enum vb2_memory memory,

			     unsigned int num_buffers, unsigned int num_planes,

			     const unsigned plane_sizes[VB2_MAX_PLANES])

			     const unsigned int plane_sizes[VB2_MAX_PLANES],

			     unsigned int *first_index)

{

	unsigned int q_num_buffers = vb2_get_num_buffers(q);

	unsigned int buffer, plane;
@@ -461,6 +464,8 @@ static int __vb2_queue_alloc(struct vb2_queue *q, enum vb2_memory memory, 
	num_buffers = min_t(unsigned int, num_buffers,

			    q->max_num_buffers - q_num_buffers);



	*first_index = q_num_buffers;



	for (buffer = 0; buffer < num_buffers; ++buffer) {

		/* Allocate vb2 buffer structures */

		vb = kzalloc(q->buf_struct_size, GFP_KERNEL);
@@ -820,7 +825,7 @@ int vb2_core_reqbufs(struct vb2_queue *q, enum vb2_memory memory, 
	unsigned int q_num_bufs = vb2_get_num_buffers(q);

	unsigned plane_sizes[VB2_MAX_PLANES] = { };

	bool non_coherent_mem = flags & V4L2_MEMORY_FLAG_NON_COHERENT;

	unsigned int i;

	unsigned int i, first_index;

	int ret = 0;



	if (q->streaming) {
@@ -907,8 +912,10 @@ int vb2_core_reqbufs(struct vb2_queue *q, enum vb2_memory memory, 


	/* Finally, allocate buffers and video memory */

	allocated_buffers =

		__vb2_queue_alloc(q, memory, num_buffers, num_planes, plane_sizes);

		__vb2_queue_alloc(q, memory, num_buffers, num_planes, plane_sizes, &first_index);

	if (allocated_buffers == 0) {

		/* There shouldn't be any buffers allocated, so first_index == 0 */

		WARN_ON(first_index);

		dprintk(q, 1, "memory allocation failed\n");

		ret = -ENOMEM;

		goto error;
@@ -982,7 +989,8 @@ EXPORT_SYMBOL_GPL(vb2_core_reqbufs); 
int vb2_core_create_bufs(struct vb2_queue *q, enum vb2_memory memory,

			 unsigned int flags, unsigned int *count,

			 unsigned int requested_planes,

			 const unsigned int requested_sizes[])

			 const unsigned int requested_sizes[],

			 unsigned int *first_index)

{

	unsigned int num_planes = 0, num_buffers, allocated_buffers;

	unsigned plane_sizes[VB2_MAX_PLANES] = { };
@@ -1044,7 +1052,7 @@ int vb2_core_create_bufs(struct vb2_queue *q, enum vb2_memory memory, 


	/* Finally, allocate buffers and video memory */

	allocated_buffers = __vb2_queue_alloc(q, memory, num_buffers,

				num_planes, plane_sizes);

				num_planes, plane_sizes, first_index);

	if (allocated_buffers == 0) {

		dprintk(q, 1, "memory allocation failed\n");

		ret = -ENOMEM;

drivers/media/common/videobuf2/videobuf2-v4l2.c

+9 −5
Original line number Diff line number Diff line
@@ -795,11 +795,15 @@ int vb2_create_bufs(struct vb2_queue *q, struct v4l2_create_buffers *create) 
	for (i = 0; i < requested_planes; i++)

		if (requested_sizes[i] == 0)

			return -EINVAL;

	return ret ? ret : vb2_core_create_bufs(q, create->memory,

	if (ret)

		return ret;



	return vb2_core_create_bufs(q, create->memory,

				    create->flags,

				    &create->count,

				    requested_planes,

						requested_sizes);

				    requested_sizes,

				    &create->index);

}

EXPORT_SYMBOL_GPL(vb2_create_bufs);

include/media/videobuf2-core.h

+4 −1
Original line number Diff line number Diff line
@@ -826,6 +826,8 @@ int vb2_core_reqbufs(struct vb2_queue *q, enum vb2_memory memory, 
 * @count: requested buffer count.

 * @requested_planes: number of planes requested.

 * @requested_sizes: array with the size of the planes.

 * @first_index: index of the first created buffer, all allocated buffers have

 *		 indices in the range [first_index..first_index+count-1]

 *

 * Videobuf2 core helper to implement VIDIOC_CREATE_BUFS() operation. It is

 * called internally by VB2 by an API-specific handler, like
@@ -842,7 +844,8 @@ int vb2_core_reqbufs(struct vb2_queue *q, enum vb2_memory memory, 
int vb2_core_create_bufs(struct vb2_queue *q, enum vb2_memory memory,

			 unsigned int flags, unsigned int *count,

			 unsigned int requested_planes,

			 const unsigned int requested_sizes[]);

			 const unsigned int requested_sizes[],

			 unsigned int *first_index);



/**

 * vb2_core_prepare_buf() - Pass ownership of a buffer from userspace