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From:   Michael Ellerman <patch-notifications@ellerman.id.au>
To:     Alexey Kardashevskiy <aik@ozlabs.ru>,
        Benjamin Herrenschmidt <benh@kernel.crashing.org>,
        Nicolin Chen <nicoleotsuka@gmail.com>,
        Leonardo Bras <leobras.c@gmail.com>,
        Michael Ellerman <mpe@ellerman.id.au>,
        Niklas Schnelle <schnelle@linux.ibm.com>,
        Paul Mackerras <paulus@samba.org>
Cc:     linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org
In-Reply-To: <20210318174414.684630-1-leobras.c@gmail.com>
References: <20210318174414.684630-1-leobras.c@gmail.com>
Subject: Re: [PATCH 1/1] powerpc/kernel/iommu: Align size for IOMMU_PAGE_SIZE() to save TCEs
Message-Id: <161970488591.4033873.12136899463811308450.b4-ty@ellerman.id.au>
Date:   Fri, 30 Apr 2021 00:01:25 +1000
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On Thu, 18 Mar 2021 14:44:14 -0300, Leonardo Bras wrote:
> Currently both iommu_alloc_coherent() and iommu_free_coherent() align the
> desired allocation size to PAGE_SIZE, and gets system pages and IOMMU
> mappings (TCEs) for that value.
> 
> When IOMMU_PAGE_SIZE < PAGE_SIZE, this behavior may cause unnecessary
> TCEs to be created for mapping the whole system page.
> 
> [...]

Applied to powerpc/next.

[1/1] powerpc/kernel/iommu: Align size for IOMMU_PAGE_SIZE() to save TCEs
      https://git.kernel.org/powerpc/c/3c0468d4451eb6b4f6604370639f163f9637a479

cheers