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From:   Pintu Agarwal <pintu.ping@gmail.com>
Date:   Tue, 1 Aug 2023 22:42:42 +0530
Message-ID: <CAOuPNLjnfq1JefngtNrg0Q+JdMTSRz+eEqxGQJFfx9+af+k9WA@mail.gmail.com>
Subject: Re: [PATCH v2] dma-contiguous: define proper name for global cma region
To:     Christoph Hellwig <hch@lst.de>
Cc:     Pintu Kumar <quic_pintu@quicinc.com>, linux-kernel@vger.kernel.org,
        akpm@linux-foundation.org, linux-mm@kvack.org,
        m.szyprowski@samsung.com, robin.murphy@arm.com,
        iommu@lists.linux.dev, Sumit Semwal <sumit.semwal@linaro.org>,
        Benjamin Gaignard <benjamin.gaignard@collabora.com>,
        Liam Mark <lmark@codeaurora.org>,
        Laura Abbott <labbott@redhat.com>,
        Brian Starkey <Brian.Starkey@arm.com>,
        John Stultz <jstultz@google.com>,
        =?UTF-8?Q?Christian_K=C3=B6nig?= <christian.koenig@amd.com>,
        linux-media@vger.kernel.org, dri-devel@lists.freedesktop.org,
        linaro-mm-sig@lists.linaro.org
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Hi Christoph,
Thank you so much for your review and comments.

On Mon, 31 Jul 2023 at 16:51, Christoph Hellwig <hch@lst.de> wrote:
>
> Hi Pintu,
>
> On Sat, Jul 29, 2023 at 08:05:15AM +0530, Pintu Kumar wrote:
> > The current global cma region name defined as "reserved"
> > which is misleading, creates confusion and too generic.
> >
> > Also, the default cma allocation happens from global cma region,
> > so, if one has to figure out all allocations happening from
> > global cma region, this seems easier.
> >
> > Thus, change the name from "reserved" to "global-cma-region".
>
> I agree that reserved is not a very useful name.  Unfortuately the
> name of the region leaks to userspace through cma_heap.
>
> So I think we need prep patches to hardcode "reserved" in
> add_default_cma_heap first, and then remove the cma_get_name
> first.

Sorry, but I could not fully understand your comments.
Can you please elaborate a little more what changes are required in
cma_heap if we change "reserved" to "global-cma-region" ?
You mean to say there are userspace tools that rely on this "reserved"
naming for global cma ?