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Subject: Re: [PATCH v4 1/2] tpm: add ptr to the tpm_space struct to file_priv
To:     Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Cc:     flihp@twobit.us, jgg@ziepe.ca, linux-integrity@vger.kernel.org,
        linux-security-module@vger.kernel.org, linux-kernel@vger.kernel.org
References: <153367365951.18015.11320230309813817454.stgit@tstruk-mobl1.jf.intel.com>
 <153367366462.18015.12915462188877575543.stgit@tstruk-mobl1.jf.intel.com>
 <20180810172700.GU4692@linux.intel.com>
From:   Tadeusz Struk <tadeusz.struk@intel.com>
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Message-ID: <2bacb3d8-3897-e147-252f-c49de9e7806b@intel.com>
Date:   Fri, 10 Aug 2018 11:05:17 -0700
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On 08/10/2018 10:27 AM, Jarkko Sakkinen wrote:
> On Tue, Aug 07, 2018 at 01:27:44PM -0700, Tadeusz Struk wrote:
>> Add a ptr to struct tpm_space to the file_priv to have an easy
>> access to it in the async job without the need to allocate memory.
>> This also allows to consolidate of the write operations for
>> the two interfaces.
> 
> I think the 2nd premise should be the priority and the first premise should
> be removed as it is not needed in any possible way to justify the
> change.

Jarkko,
The main reason why the pointer to tpm_space struct was added to the
file_priv was to have access to space in the async job when it is enqueued
via the /dev/tpm<N> interface. Currently it is only available in tpmrm_priv.
Otherwise I would need to introduce yet another struct what would consist of
a ptr file_priv and a ptr to tpm_space and allocate it on every enqueue.
Much easier was to to it this way. The consolidation was only a side effect
of this so I think the description is correct.
Thanks,
-- 
Tadeusz