diff --git a/libavcodec/cbs.c b/libavcodec/cbs.c
index 2350416501..1a43cd2694 100644
--- a/libavcodec/cbs.c
+++ b/libavcodec/cbs.c
@@ -597,7 +597,7 @@ int ff_cbs_alloc_unit_content(CodedBitstreamContext *ctx,
         return AVERROR(ENOMEM);
 
     unit->content_ref = av_buffer_create(unit->content, size,
-                                         free, ctx, 0);
+                                         free, NULL, 0);
     if (!unit->content_ref) {
         av_freep(&unit->content);
         return AVERROR(ENOMEM);
diff --git a/libavcodec/cbs.h b/libavcodec/cbs.h
index fe57e7b2a5..7c341bffe7 100644
--- a/libavcodec/cbs.h
+++ b/libavcodec/cbs.h
@@ -341,7 +341,7 @@ void ff_cbs_fragment_free(CodedBitstreamContext *ctx,
 int ff_cbs_alloc_unit_content(CodedBitstreamContext *ctx,
                               CodedBitstreamUnit *unit,
                               size_t size,
-                              void (*free)(void *unit, uint8_t *content));
+                              void (*free)(void *opaque, uint8_t *content));
 
 /**
  * Allocate a new internal data buffer of the given size in the unit.
diff --git a/libavcodec/cbs_av1.c b/libavcodec/cbs_av1.c
index 288ef8e14b..98cd37ef74 100644
--- a/libavcodec/cbs_av1.c
+++ b/libavcodec/cbs_av1.c
@@ -829,7 +829,7 @@ static void cbs_av1_free_metadata(AV1RawMetadata *md)
     }
 }
 
-static void cbs_av1_free_obu(void *unit, uint8_t *content)
+static void cbs_av1_free_obu(void *opaque, uint8_t *content)
 {
     AV1RawOBU *obu = (AV1RawOBU*)content;
 
diff --git a/libavcodec/cbs_h2645.c b/libavcodec/cbs_h2645.c
index 0f697434e5..1c35be51e7 100644
--- a/libavcodec/cbs_h2645.c
+++ b/libavcodec/cbs_h2645.c
@@ -443,7 +443,7 @@ static int cbs_h2645_read_more_rbsp_data(GetBitContext *gbc)
 #undef allocate
 
 
-static void cbs_h264_free_pps(void *unit, uint8_t *content)
+static void cbs_h264_free_pps(void *opaque, uint8_t *content)
 {
     H264RawPPS *pps = (H264RawPPS*)content;
     av_buffer_unref(&pps->slice_group_id_ref);
@@ -473,7 +473,7 @@ static void cbs_h264_free_sei_payload(H264RawSEIPayload *payload)
     }
 }
 
-static void cbs_h264_free_sei(void *unit, uint8_t *content)
+static void cbs_h264_free_sei(void *opaque, uint8_t *content)
 {
     H264RawSEI *sei = (H264RawSEI*)content;
     int i;
@@ -482,35 +482,35 @@ static void cbs_h264_free_sei(void *unit, uint8_t *content)
     av_freep(&content);
 }
 
-static void cbs_h264_free_slice(void *unit, uint8_t *content)
+static void cbs_h264_free_slice(void *opaque, uint8_t *content)
 {
     H264RawSlice *slice = (H264RawSlice*)content;
     av_buffer_unref(&slice->data_ref);
     av_freep(&content);
 }
 
-static void cbs_h265_free_vps(void *unit, uint8_t *content)
+static void cbs_h265_free_vps(void *opaque, uint8_t *content)
 {
     H265RawVPS *vps = (H265RawVPS*)content;
     av_buffer_unref(&vps->extension_data.data_ref);
     av_freep(&content);
 }
 
-static void cbs_h265_free_sps(void *unit, uint8_t *content)
+static void cbs_h265_free_sps(void *opaque, uint8_t *content)
 {
     H265RawSPS *sps = (H265RawSPS*)content;
     av_buffer_unref(&sps->extension_data.data_ref);
     av_freep(&content);
 }
 
-static void cbs_h265_free_pps(void *unit, uint8_t *content)
+static void cbs_h265_free_pps(void *opaque, uint8_t *content)
 {
     H265RawPPS *pps = (H265RawPPS*)content;
     av_buffer_unref(&pps->extension_data.data_ref);
     av_freep(&content);
 }
 
-static void cbs_h265_free_slice(void *unit, uint8_t *content)
+static void cbs_h265_free_slice(void *opaque, uint8_t *content)
 {
     H265RawSlice *slice = (H265RawSlice*)content;
     av_buffer_unref(&slice->data_ref);
@@ -545,7 +545,7 @@ static void cbs_h265_free_sei_payload(H265RawSEIPayload *payload)
     }
 }
 
-static void cbs_h265_free_sei(void *unit, uint8_t *content)
+static void cbs_h265_free_sei(void *opaque, uint8_t *content)
 {
     H265RawSEI *sei = (H265RawSEI*)content;
     int i;
@@ -1615,7 +1615,7 @@ int ff_cbs_h264_add_sei_message(CodedBitstreamContext *ctx,
         sei->nal_unit_header.nal_ref_idc   = 0;
 
         sei_ref = av_buffer_create((uint8_t*)sei, sizeof(*sei),
-                                   &cbs_h264_free_sei, ctx, 0);
+                                   &cbs_h264_free_sei, NULL, 0);
         if (!sei_ref) {
             av_freep(&sei);
             return AVERROR(ENOMEM);
diff --git a/libavcodec/cbs_jpeg.c b/libavcodec/cbs_jpeg.c
index c46abd0a45..a20f062f1b 100644
--- a/libavcodec/cbs_jpeg.c
+++ b/libavcodec/cbs_jpeg.c
@@ -82,21 +82,21 @@
 #undef xu
 
 
-static void cbs_jpeg_free_application_data(void *unit, uint8_t *content)
+static void cbs_jpeg_free_application_data(void *opaque, uint8_t *content)
 {
     JPEGRawApplicationData *ad = (JPEGRawApplicationData*)content;
     av_buffer_unref(&ad->Ap_ref);
     av_freep(&content);
 }
 
-static void cbs_jpeg_free_comment(void *unit, uint8_t *content)
+static void cbs_jpeg_free_comment(void *opaque, uint8_t *content)
 {
     JPEGRawComment *comment = (JPEGRawComment*)content;
     av_buffer_unref(&comment->Cm_ref);
     av_freep(&content);
 }
 
-static void cbs_jpeg_free_scan(void *unit, uint8_t *content)
+static void cbs_jpeg_free_scan(void *opaque, uint8_t *content)
 {
     JPEGRawScan *scan = (JPEGRawScan*)content;
     av_buffer_unref(&scan->data_ref);
diff --git a/libavcodec/cbs_mpeg2.c b/libavcodec/cbs_mpeg2.c
index 516b728a64..3e6797bd42 100644
--- a/libavcodec/cbs_mpeg2.c
+++ b/libavcodec/cbs_mpeg2.c
@@ -140,21 +140,21 @@
 #undef infer
 
 
-static void cbs_mpeg2_free_picture_header(void *unit, uint8_t *content)
+static void cbs_mpeg2_free_picture_header(void *opaque, uint8_t *content)
 {
     MPEG2RawPictureHeader *picture = (MPEG2RawPictureHeader*)content;
     av_buffer_unref(&picture->extra_information_picture.extra_information_ref);
     av_freep(&content);
 }
 
-static void cbs_mpeg2_free_user_data(void *unit, uint8_t *content)
+static void cbs_mpeg2_free_user_data(void *opaque, uint8_t *content)
 {
     MPEG2RawUserData *user = (MPEG2RawUserData*)content;
     av_buffer_unref(&user->user_data_ref);
     av_freep(&content);
 }
 
-static void cbs_mpeg2_free_slice(void *unit, uint8_t *content)
+static void cbs_mpeg2_free_slice(void *opaque, uint8_t *content)
 {
     MPEG2RawSlice *slice = (MPEG2RawSlice*)content;
     av_buffer_unref(&slice->header.extra_information_slice.extra_information_ref);
diff --git a/libavcodec/cbs_vp9.c b/libavcodec/cbs_vp9.c
index 7102bb87d3..bd172100fc 100644
--- a/libavcodec/cbs_vp9.c
+++ b/libavcodec/cbs_vp9.c
@@ -474,7 +474,7 @@ static int cbs_vp9_split_fragment(CodedBitstreamContext *ctx,
     return 0;
 }
 
-static void cbs_vp9_free_frame(void *unit, uint8_t *content)
+static void cbs_vp9_free_frame(void *opaque, uint8_t *content)
 {
     VP9RawFrame *frame = (VP9RawFrame*)content;
     av_buffer_unref(&frame->data_ref);