I really disagree with the per-cmd use_dio tracking. If we know at setup time that the loop device sector size is smaller than the sector size of the underlying device we should never allow dio, and othewise it should always work for data.
The ->transfer check also is one to be done at setup time, and there is no need for draining or mode checking for an fsync - FLUSH is always only guranteed to flush out I/O that has completed by the time it's issued. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/