tree b84db101bc9c68dd37aae7eba062abde5001ad80
parent 96bc103f4c4e470d82ba5e372191d02ad715da45
author Tejun Heo <htejun@gmail.com> 1169001242 +0900
committer Jeff Garzik <jeff@garzik.org> 1169252329 -0500

libata: initialize qc->dma_dir to DMA_NONE

libata didn't used to init qc->dma_dir to any specific value on qc
initialization and command translation path didn't set qc->dma_dir if
the command doesn't need data transfer.  This made non-data commands
to have random qc->dma_dir.

This usually doesn't cause problem because LLDs usually check
qc->protocol first and look at qc->dma_dir iff the command needs data
transfer but this doesn't hold for all LLDs.

It might be worthwhile to rename qc->dma_dir to qc->data_dir as we use
the field to tag data direction for both PIO and DMA protocols.

This problem has been spotted by James Bottomley.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: James Bottomley <James.Bottomley@SteelEye.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>