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Date:   Mon, 7 Oct 2019 18:53:15 +0200
From:   Christoph Hellwig <hch@lst.de>
To:     Mark Salyzyn <salyzyn@android.com>
Cc:     Christoph Hellwig <hch@lst.de>,
        Catalin Marinas <catalin.marinas@arm.com>,
        linux-kernel@vger.kernel.org, kernel-team@android.com,
        Andrew Morton <akpm@linux-foundation.org>,
        Yue Hu <huyue2@yulong.com>, Mike Rapoport <rppt@linux.ibm.com>,
        Will Deacon <will@kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ryohei Suzuki <ryh.szk.cmnty@gmail.com>,
        Doug Berger <opendmb@gmail.com>,
        Andrey Konovalov <andreyknvl@google.com>,
        Peng Fan <peng.fan@nxp.com>, linux-mm@kvack.org,
        Robin Murphy <robin.murphy@arm.com>
Subject: Re: [PATCH] mm: export cma alloc and release
Message-ID: <20191007165315.GA10317@lst.de>
References: <20191002212257.196849-1-salyzyn@android.com> <20191003085528.GB21629@arrakis.emea.arm.com> <20191005083753.GA14691@lst.de> <aa1c5b2f-fa90-4390-edc6-33b87fab5e09@android.com>
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On Mon, Oct 07, 2019 at 09:50:31AM -0700, Mark Salyzyn wrote:
> On 10/5/19 1:37 AM, Christoph Hellwig wrote:
>> On Thu, Oct 03, 2019 at 09:55:28AM +0100, Catalin Marinas wrote:
>>> Aren't drivers supposed to use the DMA API for such allocations rather
>>> than invoking cma_*() directly?
>> Yes, they are.
>
> We have an engineer assigned to rewriting the ion memory driver to use 
> dma_buf interfaces. Hopefully that effort will solve the problem of 
> requiring these interfaces to be exported so that that driver (and others) 
> can be modularized.
>
> Thanks for the reviews, drop this patch from the list and we will regroup, 
> and accept that standing code in the kernel can not be modularized for the 
> moment.

How is that different from the "DMA-BUF Heaps (destaging ION)" series
floating around?