[BUG] scsi: wd719x: accessing the data mapped to streaming DMA

[Jia-Ju Bai]

In wd719x_queuecommand(), "scb" is mapped to streaming DMA:
 scb->phys = dma_map_single(..., scb, ...);

Then "scb" is accessed at many places in this function, such as:
 scb->SCB_options |= WD719X_SCB_FLAGS_AUTO_REQUEST_SENSE;
 ...
 scb->data_length = 0;
 scb->data_p = 0;

These accesses may cause data inconsistency between CPU cache and hardware.

I am not sure how to properly fix this problem, and thus I only report it.


Best wishes,
Jia-Ju Bai