- /* Reserve a part of the read-ahead window that we'll be issuing */
- if (ras->ras_window_len > 0) {
- /*
- * Note: other thread might rollback the ras_next_readahead,
- * if it can not get the full size of prepared pages, see the
- * end of this function. For stride read ahead, it needs to
- * make sure the offset is no less than ras_stride_offset,
- * so that stride read ahead can work correctly.
- */
- if (stride_io_mode(ras))
- start = max(ras->ras_next_readahead,
- ras->ras_stride_offset);
- else
- start = ras->ras_next_readahead;