- area = (unsigned long)width * (unsigned long)height *
- g2d_get_buf_bpp(buf_desc->format);
- if (area > size) {
- DRM_ERROR("area[%lu] is out of range[%lu]!\n", area, size);
+ bpp = g2d_get_buf_bpp(buf_desc->format);
+
+ /* Compute the position of the last byte that the engine accesses. */
+ last_pos = ((unsigned long)buf_desc->bottom_y - 1) *
+ (unsigned long)buf_desc->stride +
+ (unsigned long)buf_desc->right_x * bpp - 1;
+
+ /*
+ * Since right_x > left_x and bottom_y > top_y we already know
+ * that the first_pos < last_pos (first_pos being the position
+ * of the first byte the engine accesses), it just remains to
+ * check if last_pos is smaller then the buffer size.
+ */
+
+ if (last_pos >= size) {
+ DRM_ERROR("last engine access position [%lu] "
+ "is out of range [%lu]!\n", last_pos, size);