From mboxrd@z Thu Jan  1 00:00:00 1970
From: Mark Lord <kernel@start.ca>
Subject: Re: [PATCH v2] libata: add support for NCQ commands for SG interface
Date: Mon, 16 Nov 2015 08:47:19 -0500
Message-ID: <5649DE67.7080509@start.ca>
References: <1445924955-11124-1-git-send-email-vinayak.kale@seagate.com>
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Cc: sumit.g.gupta@seagate.com, Vinayak Kale <vinayak.kale@seagate.com>

On 15-10-27 01:49 AM, vinayak.kale@gmail.com wrote:
> From: Vinayak Kale <vinayak.kale@seagate.com>
>
> This patch is needed to make NCQ commands with FPDMA protocol value
> (eg READ/WRITE FPDMA) work over SCSI Generic (SG) interface.
..
> +	/* For NCQ commands with FPDMA protocol, copy the tag value */
> +	if (tf->protocol == ATA_PROT_NCQ)
> +		tf->nsect = qc->tag << 3;
> +


What prevents the qc-tag value here from conflicting with in-flight I/O
using the exact same qc-tag ??