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([2404:f801:9000:1a:efea::4b1]) by smtp.gmail.com with ESMTPSA id u2sm15258266pfg.67.2021.06.15.08.24.57 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 15 Jun 2021 08:25:09 -0700 (PDT) Subject: Re: [RFC PATCH V3 08/11] swiotlb: Add bounce buffer remap address setting function To: Christoph Hellwig , Robin Murphy Cc: kys@microsoft.com, haiyangz@microsoft.com, sthemmin@microsoft.com, wei.liu@kernel.org, decui@microsoft.com, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, x86@kernel.org, hpa@zytor.com, arnd@arndb.de, dave.hansen@linux.intel.com, luto@kernel.org, peterz@infradead.org, akpm@linux-foundation.org, kirill.shutemov@linux.intel.com, rppt@kernel.org, hannes@cmpxchg.org, cai@lca.pw, krish.sadhukhan@oracle.com, saravanand@fb.com, Tianyu.Lan@microsoft.com, konrad.wilk@oracle.com, m.szyprowski@samsung.com, boris.ostrovsky@oracle.com, jgross@suse.com, sstabellini@kernel.org, joro@8bytes.org, will@kernel.org, xen-devel@lists.xenproject.org, davem@davemloft.net, kuba@kernel.org, jejb@linux.ibm.com, martin.petersen@oracle.com, iommu@lists.linux-foundation.org, linux-arch@vger.kernel.org, linux-hyperv@vger.kernel.org, linux-kernel@vger.kernel.org, linux-scsi@vger.kernel.org, netdev@vger.kernel.org, vkuznets@redhat.com, thomas.lendacky@amd.com, brijesh.singh@amd.com, sunilmut@microsoft.com References: <20210530150628.2063957-1-ltykernel@gmail.com> <20210530150628.2063957-9-ltykernel@gmail.com> <20210607064312.GB24478@lst.de> <94038087-a33c-93c5-27bf-7ec1f6f5f0e3@arm.com> <20210614153252.GA1741@lst.de> From: Tianyu Lan Message-ID: <9e347c4c-d4b9-129c-10d2-0d7ff1b917cc@gmail.com> Date: Tue, 15 Jun 2021 23:24:57 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.11.0 MIME-Version: 1.0 In-Reply-To: <20210614153252.GA1741@lst.de> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-arch@vger.kernel.org On 6/14/2021 11:32 PM, Christoph Hellwig wrote: > On Mon, Jun 14, 2021 at 02:49:51PM +0100, Robin Murphy wrote: >> FWIW, I think a better generalisation for this would be allowing >> set_memory_decrypted() to return an address rather than implicitly >> operating in-place, and hide all the various hypervisor hooks behind that. > > Yes, something like that would be a good idea. As-is > set_memory_decrypted is a pretty horribly API anyway due to passing > the address as void, and taking a size parameter while it works in units > of pages. So I'd very much welcome a major overhaul of this API. > Hi Christoph and Robin: Thanks for your suggestion. I will try this idea in the next version. Besides make the address translation into set_memory_ decrypted() and return address, do you want to make other changes to the API in order to make it more reasonable(e.g size parameter)? Thanks