> static int slave_configure (struct scsi_device *sdev)
> {
> + /* Scatter-gather buffers (all but the last) must have a length
> + * divisible by the bulk maxpacket size. Otherwise a data packet
> + * would end up being short, causing a premature end to the data
> + * transfer. Since high-speed bulk pipes have a maxpacket size
> + * of 512, we'll use that as the scsi device queue's DMA alignment
> + * mask. Guaranteeing proper alignment of the first buffer will
> + * have the desired effect because, except at the beginning and
> + * the end, scatter-gather buffers follow page boundaries. */
> + blk_queue_dma_alignment(sdev->request_queue, (512 - 1));
What about the cacheline of the last buffer? It seems to me that we have
to worry about DMA coherency.
Regards
Oliver
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