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Subject: Re: [PATCH v3 08/11] nvme-pci: Use PCI p2pmem subsystem to manage the
 CMB
To: Logan Gunthorpe <logang@deltatee.com>,
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References: <20180312193525.2855-1-logang@deltatee.com>
 <20180312193525.2855-9-logang@deltatee.com>
From: Sinan Kaya <okaya@codeaurora.org>
Message-ID: <4b08ec0b-76f4-4b67-a38b-5a1940c4c40d@codeaurora.org>
Date: Mon, 12 Mar 2018 21:55:27 -0400
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List-ID: <linux-pci.vger.kernel.org>

On 3/12/2018 3:35 PM, Logan Gunthorpe wrote:
> -	if (nvmeq->sq_cmds_io)

I think you should keep the code as it is for the case where
(!nvmeq->sq_cmds_is_io && nvmeq->sq_cmds_io)

You are changing the behavior for NVMe drives with CMB buffers.
You can change the if statement here with the statement above.

> -		memcpy_toio(&nvmeq->sq_cmds_io[tail], cmd, sizeof(*cmd));
> -	else
> -		memcpy(&nvmeq->sq_cmds[tail], cmd, sizeof(*cmd));
> +	memcpy(&nvmeq->sq_cmds[tail], cmd, sizeof(*cmd));
>  


-- 
Sinan Kaya
Qualcomm Datacenter Technologies, Inc. as an affiliate of Qualcomm Technologies, Inc.
Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project.