xdp_page_head
#define TEST_XDP_FRAME_SIZE (PAGE_SIZE - sizeof(struct xdp_page_head))
struct xdp_page_head *head =
headroom += sizeof(struct xdp_page_head);
static bool frame_was_changed(const struct xdp_page_head *head)
static bool ctx_was_changed(struct xdp_page_head *head)
static void reset_ctx(struct xdp_page_head *head)
struct xdp_page_head *head;