vaMapBuffer/vaUnMapBuffer: implemented refcounting on mapping/unmapping

Refcount mapping and unmapping of VABuffers.

src/xvba_buffer.c

@@ -209,6 +209,7 @@ create_va_buffer(
     obj_buffer->buffer_size      = size * num_elements;
     obj_buffer->buffer_data      = malloc(obj_buffer->buffer_size);
     obj_buffer->mtime            = 0;
+    obj_buffer->map_refcnt       = 0;
 
     if (!obj_buffer->buffer_data) {
         destroy_va_buffer(driver_data, obj_buffer);
@@ -227,6 +228,8 @@ destroy_va_buffer(
     if (!obj_buffer)
         return;
 
+    ASSERT(obj_buffer->map_refcnt == 0);
+
     if (obj_buffer->buffer_data) {
         free(obj_buffer->buffer_data);
         obj_buffer->buffer_data = NULL;
@@ -900,6 +903,7 @@ xvba_MapBuffer(
         return VA_STATUS_ERROR_UNKNOWN;
 
     ++obj_buffer->mtime;
+    ++obj_buffer->map_refcnt;
     return VA_STATUS_SUCCESS;
 }
 
@@ -917,6 +921,8 @@ xvba_UnmapBuffer(
         return VA_STATUS_ERROR_INVALID_BUFFER;
 
     ++obj_buffer->mtime;
+    --obj_buffer->map_refcnt;
+    ASSERT(obj_buffer->map_refcnt >= 0);
     return VA_STATUS_SUCCESS;
 }
 

src/xvba_buffer.h

@@ -33,6 +33,7 @@ struct object_buffer {
     unsigned int        max_num_elements;
     unsigned int        num_elements;
     uint64_t            mtime;
+    int32_t             map_refcnt;
 };
 
 // Create VA buffer object

src/xvba_image.c

@@ -446,6 +446,9 @@ commit_hw_image(
 
        NOTE: this assumes the user really unmaps the buffer when he is
        done with it, as it is actually required */
+
+    ASSERT(obj_buffer->map_refcnt == 0);
+
     if (obj_image->hw.mtime < obj_buffer->mtime) {
 #if USE_GLX
         if (flags & HWIMAGE_TYPE_GLX) {