[RFC,4/7] media: uapi: h264: increase size of fields
diff mbox series

Message ID 20200623182809.1375-5-ezequiel@collabora.com
State New, archived
Headers show
Series
  • media: Clean and make H264 stateless uAPI public
Related show

Commit Message

Ezequiel Garcia June 23, 2020, 6:28 p.m. UTC
Slice header syntax element 'first_mb_in_slice' can point
to the last macroblock, currently the field can only reference
65536 macroblocks which is insufficient for 8K videos.

DPB entry PicNum maximum value is 2*MaxFrameNum for interlaced
content (field_pic_flag=1).

Therefore, increase 'first_mb_in_slice' and 'pic_num'.

The v4l2_h264_dpb_entry struct needs to be padded to avoid a hole,
which will be useful to allow future uAPI extensions.

Note that v4l2_ctrl_h264_slice_params struct will be modified
in a follow-up commit, and so we defer its 64-bit padding.

Signed-off-by: Ezequiel Garcia <ezequiel@collabora.com>
---
 .../userspace-api/media/v4l/ext-ctrls-codec.rst          | 7 +++++--
 drivers/media/v4l2-core/v4l2-ctrls.c                     | 9 +++++++++
 include/media/h264-ctrls.h                               | 6 ++++--
 include/media/v4l2-h264.h                                | 2 +-
 4 files changed, 19 insertions(+), 5 deletions(-)

Comments

Nicolas Dufresne June 25, 2020, 3:01 p.m. UTC | #1
Le mardi 23 juin 2020 à 15:28 -0300, Ezequiel Garcia a écrit :
> Slice header syntax element 'first_mb_in_slice' can point
> to the last macroblock, currently the field can only reference
> 65536 macroblocks which is insufficient for 8K videos.
> 
> DPB entry PicNum maximum value is 2*MaxFrameNum for interlaced
> content (field_pic_flag=1).
> 
> Therefore, increase 'first_mb_in_slice' and 'pic_num'.
> 
> The v4l2_h264_dpb_entry struct needs to be padded to avoid a hole,
> which will be useful to allow future uAPI extensions.
> 
> Note that v4l2_ctrl_h264_slice_params struct will be modified
> in a follow-up commit, and so we defer its 64-bit padding.

This patch includes two changes, with two distinct rationale. Please
split in two, I would also add reference to the spec in the commit
messages. The explanation is also insufficient. Need to mention that
macro-blocks are 16x16, and the bounds for synthetic value
MaxFrameNum (derived from bitstream value) has not be mention either.

> 
> Signed-off-by: Ezequiel Garcia <ezequiel@collabora.com>
> ---
>  .../userspace-api/media/v4l/ext-ctrls-codec.rst          | 7 +++++--
>  drivers/media/v4l2-core/v4l2-ctrls.c                     | 9 +++++++++
>  include/media/h264-ctrls.h                               | 6 ++++--
>  include/media/v4l2-h264.h                                | 2 +-
>  4 files changed, 19 insertions(+), 5 deletions(-)
> 
> diff --git a/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst b/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst
> index 0808a36777b6..e3b5a28fb965 100644
> --- a/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst
> +++ b/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst
> @@ -1772,7 +1772,7 @@ enum v4l2_mpeg_video_h264_hierarchical_coding_type -
>      * - __u32
>        - ``header_bit_size``
>        -
> -    * - __u16
> +    * - __u32
>        - ``first_mb_in_slice``
>        -
>      * - __u8
> @@ -2046,7 +2046,10 @@ enum v4l2_mpeg_video_h264_hierarchical_coding_type -
>      * - __u16
>        - ``frame_num``
>        -
> -    * - __u16
> +    * - __u8
> +      - ``reserved[6]``
> +      - Applications and drivers must set this to zero.
> +    * - __u32
>        - ``pic_num``
>        -
>      * - __s32
> diff --git a/drivers/media/v4l2-core/v4l2-ctrls.c b/drivers/media/v4l2-core/v4l2-ctrls.c
> index 6abd023f10c7..a751c14f9c22 100644
> --- a/drivers/media/v4l2-core/v4l2-ctrls.c
> +++ b/drivers/media/v4l2-core/v4l2-ctrls.c
> @@ -1734,6 +1734,7 @@ static int std_validate_compound(const struct v4l2_ctrl *ctrl, u32 idx,
>  	struct v4l2_ctrl_mpeg2_slice_params *p_mpeg2_slice_params;
>  	struct v4l2_ctrl_vp8_frame_header *p_vp8_frame_header;
>  	struct v4l2_ctrl_h264_slice_params *p_h264_slice_params;
> +	struct v4l2_ctrl_h264_decode_params *p_h264_dec_params;
>  	struct v4l2_ctrl_hevc_sps *p_hevc_sps;
>  	struct v4l2_ctrl_hevc_pps *p_hevc_pps;
>  	struct v4l2_ctrl_hevc_slice_params *p_hevc_slice_params;
> @@ -1808,6 +1809,14 @@ static int std_validate_compound(const struct v4l2_ctrl *ctrl, u32 idx,
>  		}
>  		break;
>  	case V4L2_CTRL_TYPE_H264_DECODE_PARAMS:
> +		p_h264_dec_params = p;
> +
> +		for (i = 0; i < V4L2_H264_NUM_DPB_ENTRIES; i++) {
> +			struct v4l2_h264_dpb_entry *dpb_entry =
> +				&p_h264_dec_params->dpb[i];
> +
> +			zero_reserved(*dpb_entry);
> +		}
>  		break;
>  
>  	case V4L2_CTRL_TYPE_VP8_FRAME_HEADER:
> diff --git a/include/media/h264-ctrls.h b/include/media/h264-ctrls.h
> index c6cbf178c1c9..a938d16b901c 100644
> --- a/include/media/h264-ctrls.h
> +++ b/include/media/h264-ctrls.h
> @@ -161,7 +161,8 @@ struct v4l2_ctrl_h264_slice_params {
>  	/* Offset in bits to slice_data() from the beginning of this slice. */
>  	__u32 header_bit_size;
>  
> -	__u16 first_mb_in_slice;
> +	__u32 first_mb_in_slice;
> +
>  	__u8 slice_type;
>  	__u8 pic_parameter_set_id;
>  	__u8 colour_plane_id;
> @@ -208,7 +209,8 @@ struct v4l2_ctrl_h264_slice_params {
>  struct v4l2_h264_dpb_entry {
>  	__u64 reference_ts;
>  	__u16 frame_num;
> -	__u16 pic_num;
> +	__u8 reserved[6];
> +	__u32 pic_num;
>  	/* Note that field is indicated by v4l2_buffer.field */
>  	__s32 top_field_order_cnt;
>  	__s32 bottom_field_order_cnt;
> diff --git a/include/media/v4l2-h264.h b/include/media/v4l2-h264.h
> index bc9ebb560ccf..1a5f26fc2a9a 100644
> --- a/include/media/v4l2-h264.h
> +++ b/include/media/v4l2-h264.h
> @@ -33,7 +33,7 @@ struct v4l2_h264_reflist_builder {
>  	struct {
>  		s32 pic_order_count;
>  		int frame_num;
> -		u16 pic_num;
> +		u32 pic_num;
>  		u16 longterm : 1;
>  	} refs[V4L2_H264_NUM_DPB_ENTRIES];
>  	s32 cur_pic_order_count;
Ezequiel Garcia June 25, 2020, 3:29 p.m. UTC | #2
On Thu, 2020-06-25 at 11:01 -0400, Nicolas Dufresne wrote:
> Le mardi 23 juin 2020 à 15:28 -0300, Ezequiel Garcia a écrit :
> > Slice header syntax element 'first_mb_in_slice' can point
> > to the last macroblock, currently the field can only reference
> > 65536 macroblocks which is insufficient for 8K videos.
> > 
> > DPB entry PicNum maximum value is 2*MaxFrameNum for interlaced
> > content (field_pic_flag=1).
> > 
> > Therefore, increase 'first_mb_in_slice' and 'pic_num'.
> > 
> > The v4l2_h264_dpb_entry struct needs to be padded to avoid a hole,
> > which will be useful to allow future uAPI extensions.
> > 
> > Note that v4l2_ctrl_h264_slice_params struct will be modified
> > in a follow-up commit, and so we defer its 64-bit padding.
> 
> This patch includes two changes, with two distinct rationale. Please
> split in two, I would also add reference to the spec in the commit
> messages.

OK.

> The explanation is also insufficient. Need to mention that
> macro-blocks are 16x16, and the bounds for synthetic value
> MaxFrameNum (derived from bitstream value) has not be mention either.
> 

OK, will do.

Thanks!
Ezequiel

> > Signed-off-by: Ezequiel Garcia <ezequiel@collabora.com>
> > ---
> >  .../userspace-api/media/v4l/ext-ctrls-codec.rst          | 7 +++++--
> >  drivers/media/v4l2-core/v4l2-ctrls.c                     | 9 +++++++++
> >  include/media/h264-ctrls.h                               | 6 ++++--
> >  include/media/v4l2-h264.h                                | 2 +-
> >  4 files changed, 19 insertions(+), 5 deletions(-)
> > 
> > diff --git a/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst b/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst
> > index 0808a36777b6..e3b5a28fb965 100644
> > --- a/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst
> > +++ b/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst
> > @@ -1772,7 +1772,7 @@ enum v4l2_mpeg_video_h264_hierarchical_coding_type -
> >      * - __u32
> >        - ``header_bit_size``
> >        -
> > -    * - __u16
> > +    * - __u32
> >        - ``first_mb_in_slice``
> >        -
> >      * - __u8
> > @@ -2046,7 +2046,10 @@ enum v4l2_mpeg_video_h264_hierarchical_coding_type -
> >      * - __u16
> >        - ``frame_num``
> >        -
> > -    * - __u16
> > +    * - __u8
> > +      - ``reserved[6]``
> > +      - Applications and drivers must set this to zero.
> > +    * - __u32
> >        - ``pic_num``
> >        -
> >      * - __s32
> > diff --git a/drivers/media/v4l2-core/v4l2-ctrls.c b/drivers/media/v4l2-core/v4l2-ctrls.c
> > index 6abd023f10c7..a751c14f9c22 100644
> > --- a/drivers/media/v4l2-core/v4l2-ctrls.c
> > +++ b/drivers/media/v4l2-core/v4l2-ctrls.c
> > @@ -1734,6 +1734,7 @@ static int std_validate_compound(const struct v4l2_ctrl *ctrl, u32 idx,
> >  	struct v4l2_ctrl_mpeg2_slice_params *p_mpeg2_slice_params;
> >  	struct v4l2_ctrl_vp8_frame_header *p_vp8_frame_header;
> >  	struct v4l2_ctrl_h264_slice_params *p_h264_slice_params;
> > +	struct v4l2_ctrl_h264_decode_params *p_h264_dec_params;
> >  	struct v4l2_ctrl_hevc_sps *p_hevc_sps;
> >  	struct v4l2_ctrl_hevc_pps *p_hevc_pps;
> >  	struct v4l2_ctrl_hevc_slice_params *p_hevc_slice_params;
> > @@ -1808,6 +1809,14 @@ static int std_validate_compound(const struct v4l2_ctrl *ctrl, u32 idx,
> >  		}
> >  		break;
> >  	case V4L2_CTRL_TYPE_H264_DECODE_PARAMS:
> > +		p_h264_dec_params = p;
> > +
> > +		for (i = 0; i < V4L2_H264_NUM_DPB_ENTRIES; i++) {
> > +			struct v4l2_h264_dpb_entry *dpb_entry =
> > +				&p_h264_dec_params->dpb[i];
> > +
> > +			zero_reserved(*dpb_entry);
> > +		}
> >  		break;
> >  
> >  	case V4L2_CTRL_TYPE_VP8_FRAME_HEADER:
> > diff --git a/include/media/h264-ctrls.h b/include/media/h264-ctrls.h
> > index c6cbf178c1c9..a938d16b901c 100644
> > --- a/include/media/h264-ctrls.h
> > +++ b/include/media/h264-ctrls.h
> > @@ -161,7 +161,8 @@ struct v4l2_ctrl_h264_slice_params {
> >  	/* Offset in bits to slice_data() from the beginning of this slice. */
> >  	__u32 header_bit_size;
> >  
> > -	__u16 first_mb_in_slice;
> > +	__u32 first_mb_in_slice;
> > +
> >  	__u8 slice_type;
> >  	__u8 pic_parameter_set_id;
> >  	__u8 colour_plane_id;
> > @@ -208,7 +209,8 @@ struct v4l2_ctrl_h264_slice_params {
> >  struct v4l2_h264_dpb_entry {
> >  	__u64 reference_ts;
> >  	__u16 frame_num;
> > -	__u16 pic_num;
> > +	__u8 reserved[6];
> > +	__u32 pic_num;
> >  	/* Note that field is indicated by v4l2_buffer.field */
> >  	__s32 top_field_order_cnt;
> >  	__s32 bottom_field_order_cnt;
> > diff --git a/include/media/v4l2-h264.h b/include/media/v4l2-h264.h
> > index bc9ebb560ccf..1a5f26fc2a9a 100644
> > --- a/include/media/v4l2-h264.h
> > +++ b/include/media/v4l2-h264.h
> > @@ -33,7 +33,7 @@ struct v4l2_h264_reflist_builder {
> >  	struct {
> >  		s32 pic_order_count;
> >  		int frame_num;
> > -		u16 pic_num;
> > +		u32 pic_num;
> >  		u16 longterm : 1;
> >  	} refs[V4L2_H264_NUM_DPB_ENTRIES];
> >  	s32 cur_pic_order_count;

Patch
diff mbox series

diff --git a/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst b/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst
index 0808a36777b6..e3b5a28fb965 100644
--- a/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst
+++ b/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst
@@ -1772,7 +1772,7 @@  enum v4l2_mpeg_video_h264_hierarchical_coding_type -
     * - __u32
       - ``header_bit_size``
       -
-    * - __u16
+    * - __u32
       - ``first_mb_in_slice``
       -
     * - __u8
@@ -2046,7 +2046,10 @@  enum v4l2_mpeg_video_h264_hierarchical_coding_type -
     * - __u16
       - ``frame_num``
       -
-    * - __u16
+    * - __u8
+      - ``reserved[6]``
+      - Applications and drivers must set this to zero.
+    * - __u32
       - ``pic_num``
       -
     * - __s32
diff --git a/drivers/media/v4l2-core/v4l2-ctrls.c b/drivers/media/v4l2-core/v4l2-ctrls.c
index 6abd023f10c7..a751c14f9c22 100644
--- a/drivers/media/v4l2-core/v4l2-ctrls.c
+++ b/drivers/media/v4l2-core/v4l2-ctrls.c
@@ -1734,6 +1734,7 @@  static int std_validate_compound(const struct v4l2_ctrl *ctrl, u32 idx,
 	struct v4l2_ctrl_mpeg2_slice_params *p_mpeg2_slice_params;
 	struct v4l2_ctrl_vp8_frame_header *p_vp8_frame_header;
 	struct v4l2_ctrl_h264_slice_params *p_h264_slice_params;
+	struct v4l2_ctrl_h264_decode_params *p_h264_dec_params;
 	struct v4l2_ctrl_hevc_sps *p_hevc_sps;
 	struct v4l2_ctrl_hevc_pps *p_hevc_pps;
 	struct v4l2_ctrl_hevc_slice_params *p_hevc_slice_params;
@@ -1808,6 +1809,14 @@  static int std_validate_compound(const struct v4l2_ctrl *ctrl, u32 idx,
 		}
 		break;
 	case V4L2_CTRL_TYPE_H264_DECODE_PARAMS:
+		p_h264_dec_params = p;
+
+		for (i = 0; i < V4L2_H264_NUM_DPB_ENTRIES; i++) {
+			struct v4l2_h264_dpb_entry *dpb_entry =
+				&p_h264_dec_params->dpb[i];
+
+			zero_reserved(*dpb_entry);
+		}
 		break;
 
 	case V4L2_CTRL_TYPE_VP8_FRAME_HEADER:
diff --git a/include/media/h264-ctrls.h b/include/media/h264-ctrls.h
index c6cbf178c1c9..a938d16b901c 100644
--- a/include/media/h264-ctrls.h
+++ b/include/media/h264-ctrls.h
@@ -161,7 +161,8 @@  struct v4l2_ctrl_h264_slice_params {
 	/* Offset in bits to slice_data() from the beginning of this slice. */
 	__u32 header_bit_size;
 
-	__u16 first_mb_in_slice;
+	__u32 first_mb_in_slice;
+
 	__u8 slice_type;
 	__u8 pic_parameter_set_id;
 	__u8 colour_plane_id;
@@ -208,7 +209,8 @@  struct v4l2_ctrl_h264_slice_params {
 struct v4l2_h264_dpb_entry {
 	__u64 reference_ts;
 	__u16 frame_num;
-	__u16 pic_num;
+	__u8 reserved[6];
+	__u32 pic_num;
 	/* Note that field is indicated by v4l2_buffer.field */
 	__s32 top_field_order_cnt;
 	__s32 bottom_field_order_cnt;
diff --git a/include/media/v4l2-h264.h b/include/media/v4l2-h264.h
index bc9ebb560ccf..1a5f26fc2a9a 100644
--- a/include/media/v4l2-h264.h
+++ b/include/media/v4l2-h264.h
@@ -33,7 +33,7 @@  struct v4l2_h264_reflist_builder {
 	struct {
 		s32 pic_order_count;
 		int frame_num;
-		u16 pic_num;
+		u32 pic_num;
 		u16 longterm : 1;
 	} refs[V4L2_H264_NUM_DPB_ENTRIES];
 	s32 cur_pic_order_count;