Re: [PATCH] add scsi_cmd_ioctl (SG_IO) support for st

[Christoph Hellwig <hch@infradead.org>]

> +static void st_intr(struct scsi_cmnd *SCpnt)
> +{

What about st_done instead?  I know sd and sr use the intr names, but
they're really misleading.  Also convention for new code is to use
cmd or scmd as variable names for scsi commands.

> +static int st_init_command(struct scsi_cmnd *SCpnt)
> +{
> +	struct request *rq;
> +
> +	if (!(SCpnt->request->flags & REQ_BLOCK_PC))
> +		return 0;
> +
> +	rq = SCpnt->request;
> +	if (sizeof(rq->cmd) > sizeof(SCpnt->cmnd))
> +		return 0;
> +
> +	memcpy(SCpnt->cmnd, rq->cmd, sizeof(SCpnt->cmnd));
> +
> +	if (rq_data_dir(rq) == WRITE)
> +		SCpnt->sc_data_direction = DMA_TO_DEVICE;
> +	else if (rq->data_len)
> +		SCpnt->sc_data_direction = DMA_FROM_DEVICE;
> +	else
> +		SCpnt->sc_data_direction = DMA_NONE;
> +
> +	SCpnt->timeout_per_command = rq->timeout;
> +	SCpnt->transfersize = rq->data_len;
> +	SCpnt->done = st_intr;
> +	return 1;

This one looks obviously good, but yeah, this would much better fit into
the scsi midlayer.  Not for this patch session, though.