vkupload: implement decide_allocation vmethod

in the case of an upstream element proposing a buffer pool,
use it to allocate the buffer image with the given parameters
set by the upstream element.

Besides the buffer pool handling is sync'd with GstBaseTransform
base class.

See the case of vulkanupload ! vulkanh264enc

Co-authored-by: Victor Jaquez <vjaquez@igalia.com>
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/5651>

subprojects/gst-plugins-bad/ext/vulkan/vkupload.c

@@ -187,9 +187,6 @@ struct RawToBufferUpload
   GstVideoInfo in_info;
   GstVideoInfo out_info;
 
-  GstBufferPool *pool;
-  gboolean pool_active;
-
   gsize alloc_sizes[GST_VIDEO_MAX_PLANES];
 };
 
@@ -278,26 +275,16 @@ _raw_to_buffer_perform (gpointer impl, GstBuffer * inbuf, GstBuffer ** outbuf)
   GstVideoFrame v_frame;
   GstFlowReturn ret;
   guint i, n_mems;
+  GstBufferPool *pool;
 
-  if (!raw->pool) {
+  pool = gst_base_transform_get_buffer_pool
-    GstStructure *config;
+      (GST_BASE_TRANSFORM_CAST (raw->upload));
-    guint min = 0, max = 0;
+  if (!pool)
-    gsize size = 1;
+    return GST_FLOW_ERROR;
 
-    raw->pool = gst_vulkan_buffer_pool_new (raw->upload->device);
+  gst_buffer_pool_set_active (pool, TRUE);
-    config = gst_buffer_pool_get_config (raw->pool);
+  if ((ret = gst_buffer_pool_acquire_buffer (pool, outbuf, NULL))
-    gst_buffer_pool_config_set_params (config, raw->upload->out_caps, size, min,
+      != GST_FLOW_OK)
-        max);
-    gst_buffer_pool_set_config (raw->pool, config);
-  }
-  if (!raw->pool_active) {
-    gst_buffer_pool_set_active (raw->pool, TRUE);
-    raw->pool_active = TRUE;
-  }
-
-  if ((ret =
-          gst_buffer_pool_acquire_buffer (raw->pool, outbuf,
-              NULL)) != GST_FLOW_OK)
     goto out;
 
   if (!gst_video_frame_map (&v_frame, &raw->in_info, inbuf, GST_MAP_READ)) {
@@ -336,23 +323,13 @@ _raw_to_buffer_perform (gpointer impl, GstBuffer * inbuf, GstBuffer ** outbuf)
   ret = GST_FLOW_OK;
 
 out:
+  gst_object_unref (pool);
   return ret;
 }
 
 static void
 _raw_to_buffer_free (gpointer impl)
 {
-  struct RawToBufferUpload *raw = impl;
-
-  if (raw->pool) {
-    if (raw->pool_active) {
-      gst_buffer_pool_set_active (raw->pool, FALSE);
-    }
-    raw->pool_active = FALSE;
-    gst_object_unref (raw->pool);
-    raw->pool = NULL;
-  }
-
   g_free (impl);
 }
 
@@ -379,9 +356,6 @@ struct BufferToImageUpload
   GstVideoInfo in_info;
   GstVideoInfo out_info;
 
-  GstBufferPool *pool;
-  gboolean pool_active;
-
   GstVulkanOperation *exec;
 };
 
@@ -446,6 +420,17 @@ _buffer_to_image_perform (gpointer impl, GstBuffer * inbuf, GstBuffer ** outbuf)
   guint i, n_mems, n_planes;
   GArray *barriers = NULL;
   VkImageLayout dst_layout = VK_IMAGE_LAYOUT_TRANSFER_DST_OPTIMAL;
+  GstBufferPool *pool;
+
+  pool = gst_base_transform_get_buffer_pool
+      (GST_BASE_TRANSFORM_CAST (raw->upload));
+  if (!pool)
+    return GST_FLOW_ERROR;
+
+  gst_buffer_pool_set_active (pool, TRUE);
+  if ((ret = gst_buffer_pool_acquire_buffer (pool, outbuf, NULL))
+      != GST_FLOW_OK)
+    goto out;
 
   if (!raw->exec) {
     GstVulkanCommandPool *cmd_pool =
@@ -457,27 +442,6 @@ _buffer_to_image_perform (gpointer impl, GstBuffer * inbuf, GstBuffer ** outbuf)
     gst_object_unref (cmd_pool);
   }
 
-  if (!raw->pool) {
-    GstStructure *config;
-    guint min = 0, max = 0;
-    gsize size = 1;
-
-    raw->pool = gst_vulkan_image_buffer_pool_new (raw->upload->device);
-    config = gst_buffer_pool_get_config (raw->pool);
-    gst_buffer_pool_config_set_params (config, raw->upload->out_caps, size, min,
-        max);
-    gst_buffer_pool_set_config (raw->pool, config);
-  }
-  if (!raw->pool_active) {
-    gst_buffer_pool_set_active (raw->pool, TRUE);
-    raw->pool_active = TRUE;
-  }
-
-  if ((ret =
-          gst_buffer_pool_acquire_buffer (raw->pool, outbuf,
-              NULL)) != GST_FLOW_OK)
-    goto out;
-
   if (!gst_vulkan_operation_add_dependency_frame (raw->exec, *outbuf,
           VK_PIPELINE_STAGE_ALL_COMMANDS_BIT, VK_PIPELINE_STAGE_TRANSFER_BIT))
     goto error;
@@ -586,6 +550,7 @@ _buffer_to_image_perform (gpointer impl, GstBuffer * inbuf, GstBuffer ** outbuf)
   ret = GST_FLOW_OK;
 
 out:
+  gst_object_unref (pool);
   return ret;
 
 unlock_error:
@@ -606,15 +571,6 @@ _buffer_to_image_free (gpointer impl)
 {
   struct BufferToImageUpload *raw = impl;
 
-  if (raw->pool) {
-    if (raw->pool_active) {
-      gst_buffer_pool_set_active (raw->pool, FALSE);
-    }
-    raw->pool_active = FALSE;
-    gst_object_unref (raw->pool);
-    raw->pool = NULL;
-  }
-
   if (raw->exec) {
     if (!gst_vulkan_operation_wait (raw->exec)) {
       GST_WARNING_OBJECT (raw->upload,
@@ -651,9 +607,6 @@ struct RawToImageUpload
   GstVideoInfo in_info;
   GstVideoInfo out_info;
 
-  GstBufferPool *pool;
-  gboolean pool_active;
-
   GstBufferPool *in_pool;
   gboolean in_pool_active;
 
@@ -731,6 +684,17 @@ _raw_to_image_perform (gpointer impl, GstBuffer * inbuf, GstBuffer ** outbuf)
   GArray *barriers = NULL;
   guint i, n_mems, n_planes;
   VkImageLayout dst_layout = VK_IMAGE_LAYOUT_TRANSFER_DST_OPTIMAL;
+  GstBufferPool *pool;
+
+  pool = gst_base_transform_get_buffer_pool
+      (GST_BASE_TRANSFORM_CAST (raw->upload));
+  if (!pool)
+    return GST_FLOW_ERROR;
+
+  gst_buffer_pool_set_active (pool, TRUE);
+  if ((ret = gst_buffer_pool_acquire_buffer (pool, outbuf, NULL))
+      != GST_FLOW_OK)
+    goto out;
 
   if (!raw->exec) {
     GstVulkanCommandPool *cmd_pool =
@@ -740,27 +704,6 @@ _raw_to_image_perform (gpointer impl, GstBuffer * inbuf, GstBuffer ** outbuf)
     gst_object_unref (cmd_pool);
   }
 
-  if (!raw->pool) {
-    GstStructure *config;
-    guint min = 0, max = 0;
-    gsize size = 1;
-
-    raw->pool = gst_vulkan_image_buffer_pool_new (raw->upload->device);
-    config = gst_buffer_pool_get_config (raw->pool);
-    gst_buffer_pool_config_set_params (config, raw->upload->out_caps, size, min,
-        max);
-    gst_buffer_pool_set_config (raw->pool, config);
-  }
-  if (!raw->pool_active) {
-    gst_buffer_pool_set_active (raw->pool, TRUE);
-    raw->pool_active = TRUE;
-  }
-
-  if ((ret =
-          gst_buffer_pool_acquire_buffer (raw->pool, outbuf,
-              NULL)) != GST_FLOW_OK)
-    goto out;
-
   if (!gst_vulkan_operation_begin (raw->exec, &error))
     goto error;
 
@@ -926,6 +869,7 @@ _raw_to_image_perform (gpointer impl, GstBuffer * inbuf, GstBuffer ** outbuf)
   ret = GST_FLOW_OK;
 
 out:
+  gst_object_unref (pool);
   if (in_vk_copy)
     gst_buffer_unref (in_vk_copy);
 
@@ -949,15 +893,6 @@ _raw_to_image_free (gpointer impl)
 {
   struct RawToImageUpload *raw = impl;
 
-  if (raw->pool) {
-    if (raw->pool_active) {
-      gst_buffer_pool_set_active (raw->pool, FALSE);
-    }
-    raw->pool_active = FALSE;
-    gst_object_unref (raw->pool);
-    raw->pool = NULL;
-  }
-
   if (raw->in_pool) {
     if (raw->in_pool_active) {
       gst_buffer_pool_set_active (raw->in_pool, FALSE);
@@ -1424,6 +1359,48 @@ gst_vulkan_upload_propose_allocation (GstBaseTransform * bt,
 static gboolean
 gst_vulkan_upload_decide_allocation (GstBaseTransform * bt, GstQuery * query)
 {
+  GstVulkanUpload *vk_upload = GST_VULKAN_UPLOAD (bt);
+  GstBufferPool *pool = NULL;
+  GstStructure *config;
+  GstCaps *caps;
+  guint min, max, size;
+  gboolean update_pool;
+
+  gst_query_parse_allocation (query, &caps, NULL);
+  if (!caps)
+    return FALSE;
+
+  if (gst_query_get_n_allocation_pools (query) > 0) {
+    gst_query_parse_nth_allocation_pool (query, 0, &pool, &size, &min, &max);
+
+    update_pool = TRUE;
+  } else {
+    GstVideoInfo vinfo;
+
+    gst_video_info_init (&vinfo);
+    gst_video_info_from_caps (&vinfo, caps);
+    size = vinfo.size;
+    min = max = 0;
+    update_pool = FALSE;
+  }
+
+  if (!pool || !GST_IS_VULKAN_IMAGE_BUFFER_POOL (pool)) {
+    if (pool)
+      gst_object_unref (pool);
+    pool = gst_vulkan_image_buffer_pool_new (vk_upload->device);
+  }
+
+  config = gst_buffer_pool_get_config (pool);
+
+  gst_buffer_pool_config_set_params (config, caps, size, min, max);
+
+  gst_buffer_pool_set_config (pool, config);
+
+  if (update_pool)
+    gst_query_set_nth_allocation_pool (query, 0, pool, size, min, max);
+  else
+    gst_query_add_allocation_pool (query, pool, size, min, max);
+
   return TRUE;
 }