static int __io_splice_prep(struct io_kiocb *req,
			    const struct io_uring_sqe *sqe)
{
	struct io_splice* sp = &req->splice;
	unsigned int valid_flags = SPLICE_F_FD_IN_FIXED | SPLICE_F_ALL;
	int ret;

	if (req->flags & REQ_F_NEED_CLEANUP)
		return 0;
	if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
		return -EINVAL;

	sp->file_in = NULL;
	sp->len = READ_ONCE(sqe->len);
	sp->flags = READ_ONCE(sqe->splice_flags);

	if (unlikely(sp->flags & ~valid_flags))
		return -EINVAL;

	ret = io_file_get(NULL, req, READ_ONCE(sqe->splice_fd_in), &sp->file_in,
			  (sp->flags & SPLICE_F_FD_IN_FIXED));
	if (ret)
		return ret;
	req->flags |= REQ_F_NEED_CLEANUP;

	if (!S_ISREG(file_inode(sp->file_in)->i_mode)) {
		/*
		 * Splice operation will be punted aync, and here need to
		 * modify io_wq_work.flags, so initialize io_wq_work firstly.
		 */
		io_req_init_async(req);
		req->work.flags |= IO_WQ_WORK_UNBOUND;
	}

	return 0;
}
static int __io_splice_prep(struct io_kiocb *req,
			    const struct io_uring_sqe *sqe)
{
	struct io_splice* sp = &req->splice;
	unsigned int valid_flags = SPLICE_F_FD_IN_FIXED | SPLICE_F_ALL;
	int ret;

	if (req->flags & REQ_F_NEED_CLEANUP)
		return 0;
	if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
		return -EINVAL;

	sp->file_in = NULL;
	sp->len = READ_ONCE(sqe->len);
	sp->flags = READ_ONCE(sqe->splice_flags);

	if (unlikely(sp->flags & ~valid_flags))
		return -EINVAL;

	ret = io_file_get(NULL, req, READ_ONCE(sqe->splice_fd_in), &sp->file_in,
			  (sp->flags & SPLICE_F_FD_IN_FIXED));
	if (ret)
		return ret;
	req->flags |= REQ_F_NEED_CLEANUP;

	if (!S_ISREG(file_inode(sp->file_in)->i_mode)) {
		 
		io_req_init_async(req);
		req->work.flags |= IO_WQ_WORK_UNBOUND;
	}

	return 0;
}