Re: [PATCH v14 04/56] media: videobuf2: Use vb2_buffer instead of index

Tomasz Figa
2023-11-08T08:08:17Z

Hi Benjamin,

On Tue, Oct 31, 2023 at 05:30:12PM +0100, Benjamin Gaignard wrote:
> Directly use vb2_buffer pointer instead of index inside queue array.
>
> Signed-off-by: Benjamin Gaignard <benjamin.gaignard@collabora.com>
> ---
> .../media/common/videobuf2/videobuf2-core.c | 40 +++++----------
> .../media/common/videobuf2/videobuf2-v4l2.c | 51 +++++++++++--------
> drivers/media/dvb-core/dvb_vb2.c | 6 +--
> include/media/videobuf2-core.h | 16 +++---
> 4 files changed, 53 insertions(+), 60 deletions(-)
>

I just wanted to say that I really love this patch. Going well in the
direction I wanted to push it to, but never had enough time to do it.
Thanks!

Best regards,
Tomasz

> diff --git a/drivers/media/common/videobuf2/videobuf2-core.c b/drivers/media/common/videobuf2/videobuf2-core.c
> index 47dba2a20d73..968b7c0e7934 100644
> --- a/drivers/media/common/videobuf2/videobuf2-core.c
> +++ b/drivers/media/common/videobuf2/videobuf2-core.c
> @@ -654,9 +654,9 @@ static bool __buffers_in_use(struct vb2_queue *q)
> return false;
> }
>
> -void vb2_core_querybuf(struct vb2_queue *q, unsigned int index, void *pb)
> +void vb2_core_querybuf(struct vb2_queue *q, struct vb2_buffer *vb, void *pb)
> {
> - call_void_bufop(q, fill_user_buffer, q->bufs[index], pb);
> + call_void_bufop(q, fill_user_buffer, vb, pb);
> }
> EXPORT_SYMBOL_GPL(vb2_core_querybuf);
>
> @@ -1490,9 +1490,6 @@ static void vb2_req_unprepare(struct media_request_object *obj)
> WARN_ON(!vb->req_obj.req);
> }
>
> -int vb2_core_qbuf(struct vb2_queue *q, unsigned int index, void *pb,
> - struct media_request *req);
> -
> static void vb2_req_queue(struct media_request_object *obj)
> {
> struct vb2_buffer *vb = container_of(obj, struct vb2_buffer, req_obj);
> @@ -1507,7 +1504,7 @@ static void vb2_req_queue(struct media_request_object *obj)
> * set. We just ignore that, and expect this will be caught the
> * next time vb2_req_prepare() is called.
> */
> - err = vb2_core_qbuf(vb->vb2_queue, vb->index, NULL, NULL);
> + err = vb2_core_qbuf(vb->vb2_queue, vb, NULL, NULL);
> WARN_ON_ONCE(err && err != -EIO);
> mutex_unlock(vb->vb2_queue->lock);
> }
> @@ -1562,12 +1559,10 @@ unsigned int vb2_request_buffer_cnt(struct media_request *req)
> }
> EXPORT_SYMBOL_GPL(vb2_request_buffer_cnt);
>
> -int vb2_core_prepare_buf(struct vb2_queue *q, unsigned int index, void *pb)
> +int vb2_core_prepare_buf(struct vb2_queue *q, struct vb2_buffer *vb, void *pb)
> {
> - struct vb2_buffer *vb;
> int ret;
>
> - vb = q->bufs[index];
> if (vb->state != VB2_BUF_STATE_DEQUEUED) {
> dprintk(q, 1, "invalid buffer state %s\n",
> vb2_state_name(vb->state));
> @@ -1654,10 +1649,9 @@ static int vb2_start_streaming(struct vb2_queue *q)
> return ret;
> }
>
> -int vb2_core_qbuf(struct vb2_queue *q, unsigned int index, void *pb,
> +int vb2_core_qbuf(struct vb2_queue *q, struct vb2_buffer *vb, void *pb,
> struct media_request *req)
> {
> - struct vb2_buffer *vb;
> enum vb2_buffer_state orig_state;
> int ret;
>
> @@ -1666,8 +1660,6 @@ int vb2_core_qbuf(struct vb2_queue *q, unsigned int index, void *pb,
> return -EIO;
> }
>
> - vb = q->bufs[index];
> -
> if (!req && vb->state != VB2_BUF_STATE_IN_REQUEST &&
> q->requires_requests) {
> dprintk(q, 1, "qbuf requires a request\n");
> @@ -2240,9 +2232,8 @@ static int __find_plane_by_offset(struct vb2_queue *q, unsigned long offset,
> }
>
> int vb2_core_expbuf(struct vb2_queue *q, int *fd, unsigned int type,
> - unsigned int index, unsigned int plane, unsigned int flags)
> + struct vb2_buffer *vb, unsigned int plane, unsigned int flags)
> {
> - struct vb2_buffer *vb = NULL;
> struct vb2_plane *vb_plane;
> int ret;
> struct dma_buf *dbuf;
> @@ -2267,13 +2258,6 @@ int vb2_core_expbuf(struct vb2_queue *q, int *fd, unsigned int type,
> return -EINVAL;
> }
>
> - if (index >= q->num_buffers) {
> - dprintk(q, 1, "buffer index out of range\n");
> - return -EINVAL;
> - }
> -
> - vb = q->bufs[index];
> -
> if (plane >= vb->num_planes) {
> dprintk(q, 1, "buffer plane out of range\n");
> return -EINVAL;
> @@ -2292,20 +2276,20 @@ int vb2_core_expbuf(struct vb2_queue *q, int *fd, unsigned int type,
> flags & O_ACCMODE);
> if (IS_ERR_OR_NULL(dbuf)) {
> dprintk(q, 1, "failed to export buffer %d, plane %d\n",
> - index, plane);
> + vb->index, plane);
> return -EINVAL;
> }
>
> ret = dma_buf_fd(dbuf, flags & ~O_ACCMODE);
> if (ret < 0) {
> dprintk(q, 3, "buffer %d, plane %d failed to export (%d)\n",
> - index, plane, ret);
> + vb->index, plane, ret);
> dma_buf_put(dbuf);
> return ret;
> }
>
> dprintk(q, 3, "buffer %d, plane %d exported as %d descriptor\n",
> - index, plane, ret);
> + vb->index, plane, ret);
> *fd = ret;
>
> return 0;
> @@ -2710,7 +2694,7 @@ static int __vb2_init_fileio(struct vb2_queue *q, int read)
> * Queue all buffers.
> */
> for (i = 0; i < q->num_buffers; i++) {
> - ret = vb2_core_qbuf(q, i, NULL, NULL);
> + ret = vb2_core_qbuf(q, q->bufs[i], NULL, NULL);
> if (ret)
> goto err_reqbufs;
> fileio->bufs[i].queued = 1;
> @@ -2895,7 +2879,7 @@ static size_t __vb2_perform_fileio(struct vb2_queue *q, char __user *data, size_
>
> if (copy_timestamp)
> b->timestamp = ktime_get_ns();
> - ret = vb2_core_qbuf(q, index, NULL, NULL);
> + ret = vb2_core_qbuf(q, b, NULL, NULL);
> dprintk(q, 5, "vb2_qbuf result: %d\n", ret);
> if (ret)
> return ret;
> @@ -2998,7 +2982,7 @@ static int vb2_thread(void *data)
> if (copy_timestamp)
> vb->timestamp = ktime_get_ns();
> if (!threadio->stop)
> - ret = vb2_core_qbuf(q, vb->index, NULL, NULL);
> + ret = vb2_core_qbuf(q, vb, NULL, NULL);
> call_void_qop(q, wait_prepare, q);
> if (ret || threadio->stop)
> break;
> diff --git a/drivers/media/common/videobuf2/videobuf2-v4l2.c b/drivers/media/common/videobuf2/videobuf2-v4l2.c
> index c7a54d82a55e..d19d82a75ac6 100644
> --- a/drivers/media/common/videobuf2/videobuf2-v4l2.c
> +++ b/drivers/media/common/videobuf2/videobuf2-v4l2.c
> @@ -364,13 +364,12 @@ static void set_buffer_cache_hints(struct vb2_queue *q,
> }
>
> static int vb2_queue_or_prepare_buf(struct vb2_queue *q, struct media_device *mdev,
> - struct v4l2_buffer *b, bool is_prepare,
> - struct media_request **p_req)
> + struct vb2_buffer *vb, struct v4l2_buffer *b,
> + bool is_prepare, struct media_request **p_req)
> {
> const char *opname = is_prepare ? "prepare_buf" : "qbuf";
> struct media_request *req;
> struct vb2_v4l2_buffer *vbuf;
> - struct vb2_buffer *vb;
> int ret;
>
> if (b->type != q->type) {
> @@ -378,23 +377,11 @@ static int vb2_queue_or_prepare_buf(struct vb2_queue *q, struct media_device *md
> return -EINVAL;
> }
>
> - if (b->index >= q->num_buffers) {
> - dprintk(q, 1, "%s: buffer index out of range\n", opname);
> - return -EINVAL;
> - }
> -
> - if (q->bufs[b->index] == NULL) {
> - /* Should never happen */
> - dprintk(q, 1, "%s: buffer is NULL\n", opname);
> - return -EINVAL;
> - }
> -
> if (b->memory != q->memory) {
> dprintk(q, 1, "%s: invalid memory type\n", opname);
> return -EINVAL;
> }
>
> - vb = q->bufs[b->index];
> vbuf = to_vb2_v4l2_buffer(vb);
> ret = __verify_planes_array(vb, b);
> if (ret)
> @@ -667,7 +654,7 @@ int vb2_querybuf(struct vb2_queue *q, struct v4l2_buffer *b)
> vb = q->bufs[b->index];
> ret = __verify_planes_array(vb, b);
> if (!ret)
> - vb2_core_querybuf(q, b->index, b);
> + vb2_core_querybuf(q, vb, b);
> return ret;
> }
> EXPORT_SYMBOL(vb2_querybuf);
> @@ -723,6 +710,7 @@ EXPORT_SYMBOL_GPL(vb2_reqbufs);
> int vb2_prepare_buf(struct vb2_queue *q, struct media_device *mdev,
> struct v4l2_buffer *b)
> {
> + struct vb2_buffer *vb;
> int ret;
>
> if (vb2_fileio_is_active(q)) {
> @@ -733,9 +721,15 @@ int vb2_prepare_buf(struct vb2_queue *q, struct media_device *mdev,
> if (b->flags & V4L2_BUF_FLAG_REQUEST_FD)
> return -EINVAL;
>
> - ret = vb2_queue_or_prepare_buf(q, mdev, b, true, NULL);
> + if (b->index >= q->num_buffers) {
> + dprintk(q, 1, "buffer index out of range\n");
> + return -EINVAL;
> + }
> + vb = q->bufs[b->index];
>
> - return ret ? ret : vb2_core_prepare_buf(q, b->index, b);
> + ret = vb2_queue_or_prepare_buf(q, mdev, vb, b, true, NULL);
> +
> + return ret ? ret : vb2_core_prepare_buf(q, vb, b);
> }
> EXPORT_SYMBOL_GPL(vb2_prepare_buf);
>
> @@ -803,6 +797,7 @@ int vb2_qbuf(struct vb2_queue *q, struct media_device *mdev,
> struct v4l2_buffer *b)
> {
> struct media_request *req = NULL;
> + struct vb2_buffer *vb;
> int ret;
>
> if (vb2_fileio_is_active(q)) {
> @@ -810,10 +805,16 @@ int vb2_qbuf(struct vb2_queue *q, struct media_device *mdev,
> return -EBUSY;
> }
>
> - ret = vb2_queue_or_prepare_buf(q, mdev, b, false, &req);
> + if (b->index >= q->num_buffers) {
> + dprintk(q, 1, "buffer index out of range\n");
> + return -EINVAL;
> + }
> + vb = q->bufs[b->index];
> +
> + ret = vb2_queue_or_prepare_buf(q, mdev, vb, b, false, &req);
> if (ret)
> return ret;
> - ret = vb2_core_qbuf(q, b->index, b, req);
> + ret = vb2_core_qbuf(q, vb, b, req);
> if (req)
> media_request_put(req);
> return ret;
> @@ -873,7 +874,15 @@ EXPORT_SYMBOL_GPL(vb2_streamoff);
>
> int vb2_expbuf(struct vb2_queue *q, struct v4l2_exportbuffer *eb)
> {
> - return vb2_core_expbuf(q, &eb->fd, eb->type, eb->index,
> + struct vb2_buffer *vb;
> +
> + if (eb->index >= q->num_buffers) {
> + dprintk(q, 1, "buffer index out of range\n");
> + return -EINVAL;
> + }
> + vb = q->bufs[eb->index];
> +
> + return vb2_core_expbuf(q, &eb->fd, eb->type, vb,
> eb->plane, eb->flags);
> }
> EXPORT_SYMBOL_GPL(vb2_expbuf);
> diff --git a/drivers/media/dvb-core/dvb_vb2.c b/drivers/media/dvb-core/dvb_vb2.c
> index 909df82fed33..b322ef179f05 100644
> --- a/drivers/media/dvb-core/dvb_vb2.c
> +++ b/drivers/media/dvb-core/dvb_vb2.c
> @@ -360,7 +360,7 @@ int dvb_vb2_querybuf(struct dvb_vb2_ctx *ctx, struct dmx_buffer *b)
> dprintk(1, "[%s] buffer index out of range\n", ctx->name);
> return -EINVAL;
> }
> - vb2_core_querybuf(&ctx->vb_q, b->index, b);
> + vb2_core_querybuf(&ctx->vb_q, q->bufs[b->index], b);
> dprintk(3, "[%s] index=%d\n", ctx->name, b->index);
> return 0;
> }
> @@ -370,7 +370,7 @@ int dvb_vb2_expbuf(struct dvb_vb2_ctx *ctx, struct dmx_exportbuffer *exp)
> struct vb2_queue *q = &ctx->vb_q;
> int ret;
>
> - ret = vb2_core_expbuf(&ctx->vb_q, &exp->fd, q->type, exp->index,
> + ret = vb2_core_expbuf(&ctx->vb_q, &exp->fd, q->type, q->bufs[exp->index],
> 0, exp->flags);
> if (ret) {
> dprintk(1, "[%s] index=%d errno=%d\n", ctx->name,
> @@ -391,7 +391,7 @@ int dvb_vb2_qbuf(struct dvb_vb2_ctx *ctx, struct dmx_buffer *b)
> dprintk(1, "[%s] buffer index out of range\n", ctx->name);
> return -EINVAL;
> }
> - ret = vb2_core_qbuf(&ctx->vb_q, b->index, b, NULL);
> + ret = vb2_core_qbuf(&ctx->vb_q, q->bufs[b->index], b, NULL);
> if (ret) {
> dprintk(1, "[%s] index=%d errno=%d\n", ctx->name,
> b->index, ret);
> diff --git a/include/media/videobuf2-core.h b/include/media/videobuf2-core.h
> index 4b6a9d2ea372..cd3ff1cd759d 100644
> --- a/include/media/videobuf2-core.h
> +++ b/include/media/videobuf2-core.h
> @@ -747,7 +747,7 @@ int vb2_wait_for_all_buffers(struct vb2_queue *q);
> /**
> * vb2_core_querybuf() - query video buffer information.
> * @q: pointer to &struct vb2_queue with videobuf2 queue.
> - * @index: id number of the buffer.
> + * @vb: pointer to struct &vb2_buffer.
> * @pb: buffer struct passed from userspace.
> *
> * Videobuf2 core helper to implement VIDIOC_QUERYBUF() operation. It is called
> @@ -759,7 +759,7 @@ int vb2_wait_for_all_buffers(struct vb2_queue *q);
> *
> * Return: returns zero on success; an error code otherwise.
> */
> -void vb2_core_querybuf(struct vb2_queue *q, unsigned int index, void *pb);
> +void vb2_core_querybuf(struct vb2_queue *q, struct vb2_buffer *vb, void *pb);
>
> /**
> * vb2_core_reqbufs() - Initiate streaming.
> @@ -823,7 +823,7 @@ int vb2_core_create_bufs(struct vb2_queue *q, enum vb2_memory memory,
> * vb2_core_prepare_buf() - Pass ownership of a buffer from userspace
> * to the kernel.
> * @q: pointer to &struct vb2_queue with videobuf2 queue.
> - * @index: id number of the buffer.
> + * @vb: pointer to struct &vb2_buffer.
> * @pb: buffer structure passed from userspace to
> * &v4l2_ioctl_ops->vidioc_prepare_buf handler in driver.
> *
> @@ -839,13 +839,13 @@ int vb2_core_create_bufs(struct vb2_queue *q, enum vb2_memory memory,
> *
> * Return: returns zero on success; an error code otherwise.
> */
> -int vb2_core_prepare_buf(struct vb2_queue *q, unsigned int index, void *pb);
> +int vb2_core_prepare_buf(struct vb2_queue *q, struct vb2_buffer *vb, void *pb);
>
> /**
> * vb2_core_qbuf() - Queue a buffer from userspace
> *
> * @q: pointer to &struct vb2_queue with videobuf2 queue.
> - * @index: id number of the buffer
> + * @vb: pointer to struct &vb2_buffer.
> * @pb: buffer structure passed from userspace to
> * v4l2_ioctl_ops->vidioc_qbuf handler in driver
> * @req: pointer to &struct media_request, may be NULL.
> @@ -867,7 +867,7 @@ int vb2_core_prepare_buf(struct vb2_queue *q, unsigned int index, void *pb);
> *
> * Return: returns zero on success; an error code otherwise.
> */
> -int vb2_core_qbuf(struct vb2_queue *q, unsigned int index, void *pb,
> +int vb2_core_qbuf(struct vb2_queue *q, struct vb2_buffer *vb, void *pb,
> struct media_request *req);
>
> /**
> @@ -931,7 +931,7 @@ int vb2_core_streamoff(struct vb2_queue *q, unsigned int type);
> * @fd: pointer to the file descriptor associated with DMABUF
> * (set by driver).
> * @type: buffer type.
> - * @index: id number of the buffer.
> + * @vb: pointer to struct &vb2_buffer.
> * @plane: index of the plane to be exported, 0 for single plane queues
> * @flags: file flags for newly created file, as defined at
> * include/uapi/asm-generic/fcntl.h.
> @@ -945,7 +945,7 @@ int vb2_core_streamoff(struct vb2_queue *q, unsigned int type);
> * Return: returns zero on success; an error code otherwise.
> */
> int vb2_core_expbuf(struct vb2_queue *q, int *fd, unsigned int type,
> - unsigned int index, unsigned int plane, unsigned int flags);
> + struct vb2_buffer *vb, unsigned int plane, unsigned int flags);
>
> /**
> * vb2_core_queue_init() - initialize a videobuf2 queue
> --
> 2.39.2
>