[PATCH v4 07/19] media: uapi: h264: Increase size of DPB entry pic_num

From: Ezequiel Garcia
Date: Mon Aug 24 2020 - 23:53:42 EST


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

As specified, MaxFrameNum is 2^(log2_max_frame_num_minus4 + 4)
and log2_max_frame_num_minus4 is in the range of 0 to 12,
which means pic_num should be a 32-bit field.

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

Signed-off-by: Ezequiel Garcia <ezequiel@xxxxxxxxxxxxx>
Tested-by: Jonas Karlman <jonas@xxxxxxxxx>
---
.../userspace-api/media/v4l/ext-ctrls-codec.rst | 9 ++++++---
drivers/media/v4l2-core/v4l2-ctrls.c | 13 +++++++++++++
include/media/h264-ctrls.h | 3 ++-
include/media/v4l2-h264.h | 2 +-
4 files changed, 22 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 49febae8fd0f..3808c46718ad 100644
--- a/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst
+++ b/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst
@@ -2051,15 +2051,18 @@ enum v4l2_mpeg_video_h264_hierarchical_coding_type -
``timestamp`` field in struct :c:type:`v4l2_buffer`. Use the
:c:func:`v4l2_timeval_to_ns()` function to convert the struct
:c:type:`timeval` in struct :c:type:`v4l2_buffer` to a __u64.
- * - __u16
- - ``frame_num``
+ * - __u32
+ - ``pic_num``
-
* - __u16
- - ``pic_num``
+ - ``frame_num``
-
* - __u8
- ``fields``
- Specifies how the DPB entry is referenced. See :ref:`Reference Fields <h264_ref_fields>`
+ * - __u8
+ - ``reserved[5]``
+ - Applications and drivers must set this to zero.
* - __s32
- ``top_field_order_cnt``
-
diff --git a/drivers/media/v4l2-core/v4l2-ctrls.c b/drivers/media/v4l2-core/v4l2-ctrls.c
index 76c8dc8fb31c..b9457789fa55 100644
--- a/drivers/media/v4l2-core/v4l2-ctrls.c
+++ b/drivers/media/v4l2-core/v4l2-ctrls.c
@@ -1725,6 +1725,8 @@ static void std_log(const struct v4l2_ctrl *ctrl)

#define zero_padding(s) \
memset(&(s).padding, 0, sizeof((s).padding))
+#define zero_reserved(s) \
+ memset(&(s).reserved, 0, sizeof((s).reserved))

/*
* Compound controls validation requires setting unused fields/flags to zero
@@ -1735,6 +1737,7 @@ 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_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;
@@ -1796,7 +1799,17 @@ static int std_validate_compound(const struct v4l2_ctrl *ctrl, u32 idx,
case V4L2_CTRL_TYPE_H264_SCALING_MATRIX:
case V4L2_CTRL_TYPE_H264_PRED_WEIGHTS:
case V4L2_CTRL_TYPE_H264_SLICE_PARAMS:
+ 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 0529e75cce5f..91f6f0d43e11 100644
--- a/include/media/h264-ctrls.h
+++ b/include/media/h264-ctrls.h
@@ -213,9 +213,10 @@ struct v4l2_ctrl_h264_slice_params {

struct v4l2_h264_dpb_entry {
__u64 reference_ts;
+ __u32 pic_num;
__u16 frame_num;
- __u16 pic_num;
__u8 fields;
+ __u8 reserved[5];
/* 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;
--
2.27.0