Re: [PATCH] SATA NCQ support

[Jeff Garzik <jgarzik@pobox.com>]

Jens Axboe wrote:
> That is the typical case, ata_qc_new() succeeds but we cannot issue the
> command yet. So where do you want this logic placed? You cannot drop the
> host_lock in-between, as that could potentially change the situation.

ata_scsi_translate() in libata-scsi.c, in between the call to 
ata_scsi_qc_new() and ata_qc_issue().

something like:

	if (ata_scsi_qc_new() fails ||
	    (depth > 0 && ata_check_non_ncq_cmd()))
		complete SCSI command with 'queue full'

NOTE!

I just noticed a bug -- When ata_scsi_qc_new() fails, the code should 
complete the command with queue-full, but does not.

         qc = ata_scsi_qc_new(ap, dev, cmd, done);
         if (!qc)
                 return;