Em Mon, 9 Apr 2018 16:20:14 +0200
Hans Verkuil <hverkuil@xxxxxxxxx> escreveu:
> From: Hans Verkuil <hans.verkuil@xxxxxxxxx>
>
> The userspace-provided plane data needs to be stored in
> vb2_v4l2_buffer. Currently this information is applied by
> __fill_vb2_buffer() which is called by the core prepare_buf
> and qbuf functions, but when using requests these functions
> aren't called yet since the buffer won't be prepared until
> the media request is actually queued.
>
> In the meantime this information has to be stored somewhere
> and vb2_v4l2_buffer is a good place for it.
>
> The __fill_vb2_buffer callback now just copies the relevant
> information from vb2_v4l2_buffer into the planes array.
This patch is to hairy and do a lot more than what's
described. Please split it into one patch per change,
as otherwise we won't be able to properly review it.
>
> Signed-off-by: Hans Verkuil <hans.verkuil@xxxxxxxxx>
> ---
> drivers/media/common/videobuf2/videobuf2-core.c | 25 +-
> drivers/media/common/videobuf2/videobuf2-v4l2.c | 324 +++++++++++++-----------
> drivers/media/dvb-core/dvb_vb2.c | 3 +-
> include/media/videobuf2-core.h | 3 +-
> include/media/videobuf2-v4l2.h | 2 +
> 5 files changed, 197 insertions(+), 160 deletions(-)
>
> diff --git a/drivers/media/common/videobuf2/videobuf2-core.c b/drivers/media/common/videobuf2/videobuf2-core.c
> index d3f7bb33a54d..3d436ccb61f8 100644
> --- a/drivers/media/common/videobuf2/videobuf2-core.c
> +++ b/drivers/media/common/videobuf2/videobuf2-core.c
> @@ -968,9 +968,8 @@ static int __prepare_mmap(struct vb2_buffer *vb, const void *pb)
> {
> int ret = 0;
>
> - if (pb)
> - ret = call_bufop(vb->vb2_queue, fill_vb2_buffer,
> - vb, pb, vb->planes);
> + ret = call_bufop(vb->vb2_queue, fill_vb2_buffer,
> + vb, vb->planes);
> return ret ? ret : call_vb_qop(vb, buf_prepare, vb);
> }
>
> @@ -988,12 +987,10 @@ static int __prepare_userptr(struct vb2_buffer *vb, const void *pb)
>
> memset(planes, 0, sizeof(planes[0]) * vb->num_planes);
> /* Copy relevant information provided by the userspace */
> - if (pb) {
> - ret = call_bufop(vb->vb2_queue, fill_vb2_buffer,
> - vb, pb, planes);
> - if (ret)
> - return ret;
> - }
> + ret = call_bufop(vb->vb2_queue, fill_vb2_buffer,
> + vb, planes);
> + if (ret)
> + return ret;
>
> for (plane = 0; plane < vb->num_planes; ++plane) {
> /* Skip the plane if already verified */
> @@ -1104,12 +1101,10 @@ static int __prepare_dmabuf(struct vb2_buffer *vb, const void *pb)
>
> memset(planes, 0, sizeof(planes[0]) * vb->num_planes);
> /* Copy relevant information provided by the userspace */
> - if (pb) {
> - ret = call_bufop(vb->vb2_queue, fill_vb2_buffer,
> - vb, pb, planes);
> - if (ret)
> - return ret;
> - }
> + ret = call_bufop(vb->vb2_queue, fill_vb2_buffer,
> + vb, planes);
> + if (ret)
> + return ret;
>
> for (plane = 0; plane < vb->num_planes; ++plane) {
> struct dma_buf *dbuf = dma_buf_get(planes[plane].m.fd);
On all the above: why are you removing the check if (pb)?
Stripping a check like that is really scary!
I don't remember why those checks are/were needed, but the patch
description doesn't give any hint why this change is required, and,
on a quick glance, pb can be NULL, for instance when this is called
while setting buffers for file io, at __vb2_init_fileio():
ret = vb2_core_qbuf(q, i, NULL);
int vb2_core_qbuf(struct vb2_queue *q, unsigned int index, void *pb)
{
...
switch (vb->state) {
case VB2_BUF_STATE_DEQUEUED:
ret = __buf_prepare(vb, pb);
If this is really needed, please do such change on a separate patch,
in order to make easier to verify if everything is covered.
> diff --git a/drivers/media/common/videobuf2/videobuf2-v4l2.c b/drivers/media/common/videobuf2/videobuf2-v4l2.c
> index 4e9c77f21858..bf7a3ba9fed0 100644
> --- a/drivers/media/common/videobuf2/videobuf2-v4l2.c
> +++ b/drivers/media/common/videobuf2/videobuf2-v4l2.c
> @@ -154,9 +154,177 @@ static void vb2_warn_zero_bytesused(struct vb2_buffer *vb)
> pr_warn("use the actual size instead.\n");
> }
>
> +static int vb2_fill_vb2_v4l2_buffer(struct vb2_buffer *vb, struct v4l2_buffer *b)
> +{
> + struct vb2_queue *q = vb->vb2_queue;
> + struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
> + struct vb2_plane *planes = vbuf->planes;
> + unsigned int plane;
> + int ret;
> +
> + ret = __verify_length(vb, b);
> + if (ret < 0) {
> + dprintk(1, "plane parameters verification failed: %d\n", ret);
> + return ret;
> + }
> + if (b->field == V4L2_FIELD_ALTERNATE && q->is_output) {
> + /*
> + * If the format's field is ALTERNATE, then the buffer's field
> + * should be either TOP or BOTTOM, not ALTERNATE since that
> + * makes no sense. The driver has to know whether the
> + * buffer represents a top or a bottom field in order to
> + * program any DMA correctly. Using ALTERNATE is wrong, since
> + * that just says that it is either a top or a bottom field,
> + * but not which of the two it is.
> + */
> + dprintk(1, "the field is incorrectly set to ALTERNATE for an output buffer\n");
> + return -EINVAL;
> + }
> + vbuf->sequence = 0;
> +
> + if (V4L2_TYPE_IS_MULTIPLANAR(b->type)) {
> + switch (b->memory) {
> + case VB2_MEMORY_USERPTR:
> + for (plane = 0; plane < vb->num_planes; ++plane) {
> + planes[plane].m.userptr =
> + b->m.planes[plane].m.userptr;
> + planes[plane].length =
> + b->m.planes[plane].length;
> + }
> + break;
> + case VB2_MEMORY_DMABUF:
> + for (plane = 0; plane < vb->num_planes; ++plane) {
> + planes[plane].m.fd =
> + b->m.planes[plane].m.fd;
> + planes[plane].length =
> + b->m.planes[plane].length;
> + }
> + break;
> + default:
> + for (plane = 0; plane < vb->num_planes; ++plane) {
> + planes[plane].m.offset =
> + vb->planes[plane].m.offset;
> + planes[plane].length =
> + vb->planes[plane].length;
> + }
> + break;
> + }
> +
> + /* Fill in driver-provided information for OUTPUT types */
> + if (V4L2_TYPE_IS_OUTPUT(b->type)) {
> + /*
> + * Will have to go up to b->length when API starts
> + * accepting variable number of planes.
> + *
> + * If bytesused == 0 for the output buffer, then fall
> + * back to the full buffer size. In that case
> + * userspace clearly never bothered to set it and
> + * it's a safe assumption that they really meant to
> + * use the full plane sizes.
> + *
> + * Some drivers, e.g. old codec drivers, use bytesused == 0
> + * as a way to indicate that streaming is finished.
> + * In that case, the driver should use the
> + * allow_zero_bytesused flag to keep old userspace
> + * applications working.
> + */
> + for (plane = 0; plane < vb->num_planes; ++plane) {
> + struct vb2_plane *pdst = &planes[plane];
> + struct v4l2_plane *psrc = &b->m.planes[plane];
> +
> + if (psrc->bytesused == 0)
> + vb2_warn_zero_bytesused(vb);
> +
> + if (vb->vb2_queue->allow_zero_bytesused)
> + pdst->bytesused = psrc->bytesused;
> + else
> + pdst->bytesused = psrc->bytesused ?
> + psrc->bytesused : pdst->length;
> + pdst->data_offset = psrc->data_offset;
> + }
> + }
> + } else {
> + /*
> + * Single-planar buffers do not use planes array,
> + * so fill in relevant v4l2_buffer struct fields instead.
> + * In videobuf we use our internal V4l2_planes struct for
> + * single-planar buffers as well, for simplicity.
> + *
> + * If bytesused == 0 for the output buffer, then fall back
> + * to the full buffer size as that's a sensible default.
> + *
> + * Some drivers, e.g. old codec drivers, use bytesused == 0 as
> + * a way to indicate that streaming is finished. In that case,
> + * the driver should use the allow_zero_bytesused flag to keep
> + * old userspace applications working.
> + */
> + switch (b->memory) {
> + case VB2_MEMORY_USERPTR:
> + planes[0].m.userptr = b->m.userptr;
> + planes[0].length = b->length;
> + break;
> + case VB2_MEMORY_DMABUF:
> + planes[0].m.fd = b->m.fd;
> + planes[0].length = b->length;
> + break;
> + default:
> + planes[0].m.offset = vb->planes[0].m.offset;
> + planes[0].length = vb->planes[0].length;
> + break;
> + }
> +
> + planes[0].data_offset = 0;
> + if (V4L2_TYPE_IS_OUTPUT(b->type)) {
> + if (b->bytesused == 0)
> + vb2_warn_zero_bytesused(vb);
> +
> + if (vb->vb2_queue->allow_zero_bytesused)
> + planes[0].bytesused = b->bytesused;
> + else
> + planes[0].bytesused = b->bytesused ?
> + b->bytesused : planes[0].length;
> + } else
> + planes[0].bytesused = 0;
> +
> + }
> +
> + /* Zero flags that we handle */
> + vbuf->flags = b->flags & ~V4L2_BUFFER_MASK_FLAGS;
> + if (!vb->vb2_queue->copy_timestamp || !V4L2_TYPE_IS_OUTPUT(b->type)) {
> + /*
> + * Non-COPY timestamps and non-OUTPUT queues will get
> + * their timestamp and timestamp source flags from the
> + * queue.
> + */
> + vbuf->flags &= ~V4L2_BUF_FLAG_TSTAMP_SRC_MASK;
> + }
> +
> + if (V4L2_TYPE_IS_OUTPUT(b->type)) {
> + /*
> + * For output buffers mask out the timecode flag:
> + * this will be handled later in vb2_qbuf().
> + * The 'field' is valid metadata for this output buffer
> + * and so that needs to be copied here.
> + */
> + vbuf->flags &= ~V4L2_BUF_FLAG_TIMECODE;
> + vbuf->field = b->field;
> + } else {
> + /* Zero any output buffer flags as this is a capture buffer */
> + vbuf->flags &= ~V4L2_BUFFER_OUT_FLAGS;
> + /* Zero last flag, this is a signal from driver to userspace */
> + vbuf->flags &= ~V4L2_BUF_FLAG_LAST;
> + }
> +
> + return 0;
> +}
> +
As I said at the beginning, just this change, with apparently moves part of
the logic from __fill_vb2_buffer() into a separate function should be done
in a separate patch, and then a followup patch doing the required changes.
That would help us to check what changed in this part of the code
were changed due to the request API needs.
> static int vb2_queue_or_prepare_buf(struct vb2_queue *q, struct v4l2_buffer *b,
> const char *opname)
> {
> + struct vb2_v4l2_buffer *vbuf;
> + struct vb2_buffer *vb;
> + int ret;
> +
> if (b->type != q->type) {
> dprintk(1, "%s: invalid buffer type\n", opname);
> return -EINVAL;
> @@ -178,7 +346,15 @@ static int vb2_queue_or_prepare_buf(struct vb2_queue *q, struct v4l2_buffer *b,
> return -EINVAL;
> }
>
> - return __verify_planes_array(q->bufs[b->index], b);
> + vb = q->bufs[b->index];
> + vbuf = to_vb2_v4l2_buffer(vb);
> + ret = __verify_planes_array(vb, b);
> + if (ret)
> + return ret;
> +
> + /* Copy relevant information provided by the userspace */
> + memset(vbuf->planes, 0, sizeof(vbuf->planes[0]) * vb->num_planes);
> + return vb2_fill_vb2_v4l2_buffer(vb, b);
> }
>
> /*
> @@ -291,153 +467,19 @@ static void __fill_v4l2_buffer(struct vb2_buffer *vb, void *pb)
> * v4l2_buffer by the userspace. It also verifies that struct
> * v4l2_buffer has a valid number of planes.
> */
> -static int __fill_vb2_buffer(struct vb2_buffer *vb,
> - const void *pb, struct vb2_plane *planes)
> +static int __fill_vb2_buffer(struct vb2_buffer *vb, struct vb2_plane *planes)
> {
> - struct vb2_queue *q = vb->vb2_queue;
> - const struct v4l2_buffer *b = pb;
> struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
> unsigned int plane;
> - int ret;
>
> - ret = __verify_length(vb, b);
> - if (ret < 0) {
> - dprintk(1, "plane parameters verification failed: %d\n", ret);
> - return ret;
> - }
> - if (b->field == V4L2_FIELD_ALTERNATE && q->is_output) {
> - /*
> - * If the format's field is ALTERNATE, then the buffer's field
> - * should be either TOP or BOTTOM, not ALTERNATE since that
> - * makes no sense. The driver has to know whether the
> - * buffer represents a top or a bottom field in order to
> - * program any DMA correctly. Using ALTERNATE is wrong, since
> - * that just says that it is either a top or a bottom field,
> - * but not which of the two it is.
> - */
> - dprintk(1, "the field is incorrectly set to ALTERNATE for an output buffer\n");
> - return -EINVAL;
> - }
> vb->timestamp = 0;
> - vbuf->sequence = 0;
> -
> - if (V4L2_TYPE_IS_MULTIPLANAR(b->type)) {
> - if (b->memory == VB2_MEMORY_USERPTR) {
> - for (plane = 0; plane < vb->num_planes; ++plane) {
> - planes[plane].m.userptr =
> - b->m.planes[plane].m.userptr;
> - planes[plane].length =
> - b->m.planes[plane].length;
> - }
> - }
> - if (b->memory == VB2_MEMORY_DMABUF) {
> - for (plane = 0; plane < vb->num_planes; ++plane) {
> - planes[plane].m.fd =
> - b->m.planes[plane].m.fd;
> - planes[plane].length =
> - b->m.planes[plane].length;
> - }
> - }
> -
> - /* Fill in driver-provided information for OUTPUT types */
> - if (V4L2_TYPE_IS_OUTPUT(b->type)) {
> - /*
> - * Will have to go up to b->length when API starts
> - * accepting variable number of planes.
> - *
> - * If bytesused == 0 for the output buffer, then fall
> - * back to the full buffer size. In that case
> - * userspace clearly never bothered to set it and
> - * it's a safe assumption that they really meant to
> - * use the full plane sizes.
> - *
> - * Some drivers, e.g. old codec drivers, use bytesused == 0
> - * as a way to indicate that streaming is finished.
> - * In that case, the driver should use the
> - * allow_zero_bytesused flag to keep old userspace
> - * applications working.
> - */
> - for (plane = 0; plane < vb->num_planes; ++plane) {
> - struct vb2_plane *pdst = &planes[plane];
> - struct v4l2_plane *psrc = &b->m.planes[plane];
> -
> - if (psrc->bytesused == 0)
> - vb2_warn_zero_bytesused(vb);
>
> - if (vb->vb2_queue->allow_zero_bytesused)
> - pdst->bytesused = psrc->bytesused;
> - else
> - pdst->bytesused = psrc->bytesused ?
> - psrc->bytesused : pdst->length;
> - pdst->data_offset = psrc->data_offset;
> - }
> - }
> - } else {
> - /*
> - * Single-planar buffers do not use planes array,
> - * so fill in relevant v4l2_buffer struct fields instead.
> - * In videobuf we use our internal V4l2_planes struct for
> - * single-planar buffers as well, for simplicity.
> - *
> - * If bytesused == 0 for the output buffer, then fall back
> - * to the full buffer size as that's a sensible default.
> - *
> - * Some drivers, e.g. old codec drivers, use bytesused == 0 as
> - * a way to indicate that streaming is finished. In that case,
> - * the driver should use the allow_zero_bytesused flag to keep
> - * old userspace applications working.
> - */
> - if (b->memory == VB2_MEMORY_USERPTR) {
> - planes[0].m.userptr = b->m.userptr;
> - planes[0].length = b->length;
> - }
> -
> - if (b->memory == VB2_MEMORY_DMABUF) {
> - planes[0].m.fd = b->m.fd;
> - planes[0].length = b->length;
> - }
> -
> - if (V4L2_TYPE_IS_OUTPUT(b->type)) {
> - if (b->bytesused == 0)
> - vb2_warn_zero_bytesused(vb);
> -
> - if (vb->vb2_queue->allow_zero_bytesused)
> - planes[0].bytesused = b->bytesused;
> - else
> - planes[0].bytesused = b->bytesused ?
> - b->bytesused : planes[0].length;
> - } else
> - planes[0].bytesused = 0;
> -
> - }
> -
> - /* Zero flags that the vb2 core handles */
> - vbuf->flags = b->flags & ~V4L2_BUFFER_MASK_FLAGS;
> - if (!vb->vb2_queue->copy_timestamp || !V4L2_TYPE_IS_OUTPUT(b->type)) {
> - /*
> - * Non-COPY timestamps and non-OUTPUT queues will get
> - * their timestamp and timestamp source flags from the
> - * queue.
> - */
> - vbuf->flags &= ~V4L2_BUF_FLAG_TSTAMP_SRC_MASK;
> + for (plane = 0; plane < vb->num_planes; ++plane) {
> + planes[plane].m = vbuf->planes[plane].m;
> + planes[plane].length = vbuf->planes[plane].length;
> + planes[plane].bytesused = vbuf->planes[plane].bytesused;
> + planes[plane].data_offset = vbuf->planes[plane].data_offset;
> }
> -
> - if (V4L2_TYPE_IS_OUTPUT(b->type)) {
> - /*
> - * For output buffers mask out the timecode flag:
> - * this will be handled later in vb2_qbuf().
> - * The 'field' is valid metadata for this output buffer
> - * and so that needs to be copied here.
> - */
> - vbuf->flags &= ~V4L2_BUF_FLAG_TIMECODE;
> - vbuf->field = b->field;
> - } else {
> - /* Zero any output buffer flags as this is a capture buffer */
> - vbuf->flags &= ~V4L2_BUFFER_OUT_FLAGS;
> - /* Zero last flag, this is a signal from driver to userspace */
> - vbuf->flags &= ~V4L2_BUF_FLAG_LAST;
> - }
> -
> return 0;
> }
I got lost with that huge code churn that started with the addition of
a new vb2_fill_vb2_v4l2_buffer() function. Is it replacing __fill_vb2_buffer()?
Why?
Please rework on it in order to minimize the diffstat, as it is very hard
to see if the code is an exact copy or if something else got changed.
> diff --git a/drivers/media/dvb-core/dvb_vb2.c b/drivers/media/dvb-core/dvb_vb2.c
> index b811adf88afa..da6a8cec7d42 100644
> --- a/drivers/media/dvb-core/dvb_vb2.c
> +++ b/drivers/media/dvb-core/dvb_vb2.c
> @@ -146,8 +146,7 @@ static void _fill_dmx_buffer(struct vb2_buffer *vb, void *pb)
> dprintk(3, "[%s]\n", ctx->name);
> }
>
> -static int _fill_vb2_buffer(struct vb2_buffer *vb,
> - const void *pb, struct vb2_plane *planes)
> +static int _fill_vb2_buffer(struct vb2_buffer *vb, struct vb2_plane *planes)
> {
> struct dvb_vb2_ctx *ctx = vb2_get_drv_priv(vb->vb2_queue);
>
> diff --git a/include/media/videobuf2-core.h b/include/media/videobuf2-core.h
> index f6818f732f34..224c4820a044 100644
> --- a/include/media/videobuf2-core.h
> +++ b/include/media/videobuf2-core.h
> @@ -417,8 +417,7 @@ struct vb2_ops {
> struct vb2_buf_ops {
> int (*verify_planes_array)(struct vb2_buffer *vb, const void *pb);
> void (*fill_user_buffer)(struct vb2_buffer *vb, void *pb);
> - int (*fill_vb2_buffer)(struct vb2_buffer *vb, const void *pb,
> - struct vb2_plane *planes);
> + int (*fill_vb2_buffer)(struct vb2_buffer *vb, struct vb2_plane *planes);
Hmm... what happens if pb is NULL - with can happen for read()?
> void (*copy_timestamp)(struct vb2_buffer *vb, const void *pb);
> };
>
> diff --git a/include/media/videobuf2-v4l2.h b/include/media/videobuf2-v4l2.h
> index 3d5e2d739f05..097bf3e6951d 100644
> --- a/include/media/videobuf2-v4l2.h
> +++ b/include/media/videobuf2-v4l2.h
> @@ -32,6 +32,7 @@
> * &enum v4l2_field.
> * @timecode: frame timecode.
> * @sequence: sequence count of this frame.
> + * @planes: plane information (userptr/fd, length, bytesused, data_offset).
> *
> * Should contain enough information to be able to cover all the fields
> * of &struct v4l2_buffer at ``videodev2.h``.
> @@ -43,6 +44,7 @@ struct vb2_v4l2_buffer {
> __u32 field;
> struct v4l2_timecode timecode;
> __u32 sequence;
> + struct vb2_plane planes[VB2_MAX_PLANES];
> };
>
> /*
Thanks,
Mauro
