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Subject: Re: [v4,4/8] char: rpmb: provide user space interface
To: "Winkler, Tomas" <tomas.winkler@intel.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Ulf Hansson <ulf.hansson@linaro.org>,
        Adrian Hunter <adrian.hunter@intel.com>,
        James Bottomley <James.Bottomley@HansenPartnership.com>,
        "Martin K. Petersen" <martin.petersen@oracle.com>,
        Vinayak Holikatti <vinholikatti@gmail.com>,
        Andy Lutomirski <luto@kernel.org>,
        =?UTF-8?Q?Arve_Hj=c3=b8nnev=c3=a5g?= <arve@android.com>,
        Michael Ryleev <gmar@google.com>, Joao Pinto <Joao.Pinto@synopsys.com>,
        Christoph Hellwig <hch@lst.de>, Yaniv Gardi <ygardi@codeaurora.org>
References: <1464817292-5407-5-git-send-email-tomas.winkler@intel.com>
Cc: linux-kernel@vger.kernel.org, linux-mmc@vger.kernel.org,
        linux-scsi@vger.kernel.org
From: =?UTF-8?B?SsOpcsO0bWUgRm9yaXNzaWVy?= <jerome.forissier@linaro.org>
Message-ID: <57503859.6090605@linaro.org>
Date: Thu, 2 Jun 2016 15:44:57 +0200
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Hi Tomas,

On 06/01/2016 11:41 PM, Winkler, Tomas wrote:
> The user space API is achieved via single synchronous IOCTL.
> The request is submitted in in_frames_ptr pointer and received
> in out_frames_ptr.

I like this, because it's exactly what I wish existed when I wrote the
eMMC RPMB back-end for OP-TEE secure storage [1] ;-)

Same goes for patch 5/8 "char: rpmb: add RPMB simulation device": with
this I could just drop my custom simulation layer.

So, this goes in the right direction IMHO.

[1]
https://github.com/OP-TEE/optee_client/blob/master/tee-supplicant/src/rpmb.c

-- 
Jerome