From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from DM1PR04CU001.outbound.protection.outlook.com (mail-centralusazon11010067.outbound.protection.outlook.com [52.101.61.67]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 011193DC4DD for ; Tue, 9 Jun 2026 07:31:41 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=fail smtp.client-ip=52.101.61.67 ARC-Seal:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780990303; cv=fail; b=c4/ewz6htBc4NJrOS7SshxxyPsm6YeAx04npPaaheIjaQlsjvwEMfnG0zgp2X/Be0jAtPWGBzMZnKmb/KrruVtnQ1Cbju6eYnKC0dhY/P+p1pg8ZM9IHJZVwC8yiF6Gi8bqLvJ7zWRj6AXaMYHi4B8ma4zfB9kZE/UWRIUCO5E0= ARC-Message-Signature:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780990303; c=relaxed/simple; bh=FGn7u6q+CWLyTsBJHUbqGhvjl8+DTTFbz9nt6VlEIIg=; h=Message-ID:Date:Subject:To:Cc:References:From:In-Reply-To: Content-Type:MIME-Version; b=F+8DLU3/sA+CD4ZU8AhXpmvdB9cTnFs16L7MdQ5oyMBNo5AUSOqRASg8wUCV/95UJKsOKjc6YlP+JJhrEb2emQ4AlfUAp9r6rqaRr61d8t0eIHgQZTWuZmllJWUiL5YPPMuG1ZH3rgZMZIZq74KyFbYe01TZ/NLv7RBy9vgMpMI= ARC-Authentication-Results:i=2; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=amd.com; spf=fail smtp.mailfrom=amd.com; dkim=pass (1024-bit key) header.d=amd.com header.i=@amd.com header.b=ZnsR+DEG; arc=fail smtp.client-ip=52.101.61.67 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=amd.com Authentication-Results: smtp.subspace.kernel.org; spf=fail smtp.mailfrom=amd.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=amd.com header.i=@amd.com header.b="ZnsR+DEG" ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=C6MdEFXOW82/78zRm4jzcOGTdbIBSNG/0dOz8TCVheAt0NPWLEXQkLxKGPdc6qM/lbbfq9mkD/CqxFOLlYTy2gu5UGPHfRuMMME3mfOlWjwwE9YcVGRKYTAQx90AcaY8uiHCb23h+oJDIQzQUkwgiMLcRQ064/oRgkPqbS0FGainIyqLuWxbSt6p4/Bv1cA9YST53ffSDMeZMpdvS27y2gpx1JvujWT0uwB9gRjaAQANzP9fsXCHCSL4L87cVVOzfSbY/Xh7HxlHAZklMweksKJbxyAYIwOs5msWq/6lOq5V3CJeCHJj9KRvgwLq4bJ4FN9YbSoAin2lUiKkVS8RmQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector10001; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-AntiSpam-MessageData-ChunkCount:X-MS-Exchange-AntiSpam-MessageData-0:X-MS-Exchange-AntiSpam-MessageData-1; bh=+69BT9xQ7xY85k/YF/KKyra/oYCb/rP5Oy/H2j/EQRo=; b=j00REv9Nx8FDfj9skPQJzD22NYdsPjIS6K8xLyiCaHKh2f7NHigBfWfbgLSnw2Cg1t6oB9HS2gNHnNDcBdq1Wrc//lTK82OF/0Jr8y+gVl+YM+lYgP8sbeRgomBqJqKbNkZbfO+F8OoL0G0vC/VdVchRdqZgBLemvbmxVhP0NdCCa78GUhhiTwfLnryw2qUsk9x2bf98ShJGzHHUvEVCFl8/RlEKlsB1hg9Lb/CHukB2Ax2/cbhkhaI/BiToXvHCClUuzZVTkXyxij1FpFqhGMs4n4l+GeIARjh9Mz0AGlOPZQRTbRyeEMVKsDY3KQ3g0FY+9kfIqizcpGzs+GKYIw== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=amd.com; dmarc=pass action=none header.from=amd.com; dkim=pass header.d=amd.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amd.com; s=selector1; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=+69BT9xQ7xY85k/YF/KKyra/oYCb/rP5Oy/H2j/EQRo=; b=ZnsR+DEGQ6uBEtYci0cLx/Bet7ysrxl25Nw1ChNR9Ahw+DN+Hd3VDrrEiQr9s1xFcVICE/oSV56dwmmDL+zhecbR4dKhY3nUPWHR1iBoxsxh1ZGjuNE9Otelrel+sZ7TNaaN1AMltT79QgYcJCYWgN3NuCeMu90+CIJ2f3e1igo= Authentication-Results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=amd.com; Received: from BN9PR12MB5259.namprd12.prod.outlook.com (2603:10b6:408:100::17) by PH7PR12MB6489.namprd12.prod.outlook.com (2603:10b6:510:1f7::21) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.21.92.13; Tue, 9 Jun 2026 07:31:37 +0000 Received: from BN9PR12MB5259.namprd12.prod.outlook.com ([fe80::122c:cca7:c2b3:90ed]) by BN9PR12MB5259.namprd12.prod.outlook.com ([fe80::122c:cca7:c2b3:90ed%4]) with mapi id 15.21.0092.011; Tue, 9 Jun 2026 07:31:37 +0000 Message-ID: Date: Tue, 9 Jun 2026 13:01:21 +0530 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 6/7] drivers/migrate_offload: add DMA batch copy driver (dcbm) To: Karim Manaouil Cc: akpm@linux-foundation.org, david@kernel.org, kinseyho@google.com, weixugc@google.com, ljs@kernel.org, Liam.Howlett@oracle.com, vbabka@kernel.org, willy@infradead.org, rppt@kernel.org, surenb@google.com, mhocko@suse.com, ziy@nvidia.com, matthew.brost@intel.com, joshua.hahnjy@gmail.com, rakie.kim@sk.com, byungchul@sk.com, gourry@gourry.net, ying.huang@linux.alibaba.com, apopple@nvidia.com, dave@stgolabs.net, Jonathan.Cameron@huawei.com, rkodsara@amd.com, vkoul@kernel.org, bharata@amd.com, sj@kernel.org, rientjes@google.com, xuezhengchu@huawei.com, yiannis@zptcorp.com, dave.hansen@intel.com, hannes@cmpxchg.org, jhubbard@nvidia.com, peterx@redhat.com, riel@surriel.com, shakeel.butt@linux.dev, stalexan@redhat.com, tj@kernel.org, nifan.cxl@gmail.com, jic23@kernel.org, aneesh.kumar@kernel.org, nathan.lynch@amd.com, Frank.li@nxp.com, djbw@kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org References: <20260428155043.39251-2-shivankg@amd.com> <20260428155043.39251-14-shivankg@amd.com> <20260609000009.dvh7gfbmiz76eliu@wrangler> Content-Language: en-US From: "Garg, Shivank" In-Reply-To: <20260609000009.dvh7gfbmiz76eliu@wrangler> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-ClientProxiedBy: PN3PR01CA0068.INDPRD01.PROD.OUTLOOK.COM (2603:1096:c01:99::9) To BN9PR12MB5259.namprd12.prod.outlook.com (2603:10b6:408:100::17) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: BN9PR12MB5259:EE_|PH7PR12MB6489:EE_ X-MS-Office365-Filtering-Correlation-Id: 11f0bc16-9846-40ef-14bb-08dec5f923b7 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|1800799024|366016|7416014|376014|6133799003|18002099003|22082099003|11063799006|4143699003|56012099006; X-Microsoft-Antispam-Message-Info: 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 X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:BN9PR12MB5259.namprd12.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230040)(1800799024)(366016)(7416014)(376014)(6133799003)(18002099003)(22082099003)(11063799006)(4143699003)(56012099006);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?utf-8?B?YmFnTHBHVlB0ZHRQd1k3dllaTUtDRFk2V1dOS3Y5bXU5cHc5NGcxRjBmQlNa?= =?utf-8?B?c2RoR0FuR1U3aVhIVUU0SFpwRFJrTTE0dHh6SktEbExnRG5ESjNIQTBPdjdM?= =?utf-8?B?NjlDMHZ1aFRaN2VLaDFNZTA0b2JhZkJMZVM4NnBzaUpaSVp5dWVtMGJRbDIw?= =?utf-8?B?eTZ1ZVZzcklhYUl1a3VxdVJUY0hhKzk3cTlIdmlubStvNEtUZGdsR2ZyeWZJ?= =?utf-8?B?UWNtWmJsR0xmUlFreFVhOHdIMldTWHdOVGlMR0FmV1VmdEQxcnBrK0FqODlz?= =?utf-8?B?TFZwUzNNOW5MRng0bWk5NVRYMU9oT3N4M3NiQTNYbjVnMnJjYTk2QzFWeWdk?= =?utf-8?B?VGlvWTdqR3pEU003TVRwYTF0TzZQajFhVkNpSk9nL1UydndUTmMxc1hYc28x?= =?utf-8?B?RCt6MEJOZmVhNHBCSExLZU82N2U1eVlQZVRvOFBNdGMxRFNEQjNIZ0VyTEVW?= =?utf-8?B?VUwvRnE3TEZ6K205UVR6dy9OZUxsT0d6N0E3cnNsamxPVmlxWXhYa3RJYjBi?= =?utf-8?B?d2pNd1B4ZWpxMXRMQitxOXcvWFpyWnFLbGQwcTQ1YVUvbVJkb1lLdTZRQk14?= =?utf-8?B?UUV5M2R3U2d4MjFPeTRTZ1ZPM3lrWW1OaTJtL2Z6OEJWU3I4Q3ppNngvNHZj?= =?utf-8?B?emVobVNNcVNsUUtQMm9FTFBuMW9VT1gwKzlKbUQ5T3NvbFR0VEZVSEhMclNI?= =?utf-8?B?aG8xOUUrbGYzZmJMbFJFYXlOVW5SSEFnQXJEejhIYkRNUEd1WmhKdTNOQ2RU?= =?utf-8?B?NWlOclp4bDlZczVhZVJiWjB1QXpKMzJteFk2eW4yNDdTbHlnczlnWmxHZHg1?= =?utf-8?B?RXRuQkdHeHhOQlpNbUhtN2w5bFdvUExmNHhKTzJuQkxaK1FBVFlqbEt5dWln?= =?utf-8?B?cnN3S1UxQ0NOUlppRE9RMkxsMGhRb3RGTHpKSEZ4VEhnTDFLcU8xSUJ4Yisv?= =?utf-8?B?S3lpUFpvSWd5bXoxMlhRaW8yMnB0WWw1RXg1RjdScU1tVnFGM0FOVUtSVTNt?= =?utf-8?B?OVVWcEJnTk5sakduQ2xsclUwcUJqU3hSdm12bHk5TWV4d3l0QnZ5NUxXZnNS?= =?utf-8?B?dU1hYmk4ZVdkaDhBQlBoeHgzcVk3VkJIcFNzS2dxZ1pCNEJyUGdYd0JFeEd2?= =?utf-8?B?UHlaMjB5c0JNL2NqcCtjeGVzdld4ekc1dnNYTE9tMU1STkkvNTBzZTVYOTBk?= =?utf-8?B?dHduTFJRSEs5RC93MG9pUGhRTjQ0bmFTOE1Jam9mdkpQMFdzalI1bURmOGtC?= =?utf-8?B?ek5hVThwaGF1RHB3WVRaUFhlang3OXN6eGtPUGJjaHI4RmlBNDlyZFhoTmRD?= =?utf-8?B?cFlwSjNNQkhROG15NmxDYkxDRndaSlBsNURxcGFvNWxCTkZ0RE9nZmp5RG5w?= =?utf-8?B?R3VpRlpOdDY1cXVWaFNrQm1MZ0tMYzY5Q3hYbUp2TjlydDJhbkgrcWtQa0FD?= =?utf-8?B?V2h3TUgwWkIrNU9CUEd1SW12K1hqUjZkcFJQemkxa1g4bVdlNnpUWVJsQTNO?= =?utf-8?B?YzZNZVpZNjJwSmIyQUVVT3ZwM0Mxb1gzVXZHSmZJVHFRVGNvWGtFTFB2bGJn?= =?utf-8?B?NEs2UHpzUjNxb2Z4WU0rVU54cmQ0Q00xK2R6M3pHVDlWV0h1NUU5U1dWc3ds?= =?utf-8?B?WmN2dWVXVVIvaXVSa1J4RnI5ZjlXYjV5aUduUkZBVXJiUWtrMW8yT2xKeE9v?= =?utf-8?B?Y0lVN1M5Tkc2RGZMSWw2N0Z3dTRBYWZDenBFOHkrblZGaHpXMGNoOGh3VkRR?= =?utf-8?B?ZkJXQWN4aDhUYzVUYklWYk9vYWNUcmpqczVpd0UwSG5qbEp3L09MRlI5QS9s?= =?utf-8?B?SG9BVGF5N2Y4S2k3UlFZL1VUT3RzV2FadWt1TXlIT2hjSk9FVDVmc0xuQkZv?= =?utf-8?B?Wk80YlZQSDN1UnpROWkwcUpvOGtrNnlLRVk1d3FSMTRvdURBSGEvalp6eTBq?= =?utf-8?B?dmUvOUswN1ZLR1htMVdkWVVSSHVJSWhtLzMvTFRzUDhyNE1sVEFTb2NOdmUx?= =?utf-8?B?K1J2aU1WSHZWTks1SjdNekJYOE15VFBXUlJMSHJ6Qkt4NENCV29TNGVyZGUw?= =?utf-8?B?Ky9lbTBneUo2RmdpVTZROGhnc3J4dytRd0xkR1FUcU13SG5sYkI1amtkYXFR?= =?utf-8?B?eDA2bmI2N3NheFBOV2lkUzdScTljSUlESkxqQnhSZ0NaQ1A4NkxWaWd1L05L?= =?utf-8?B?czcxNkRFeUIrQ1o1Wklqc2pPT1UzQlFlNmFPL3h1QmZtQVllZGlsUlc4enZr?= =?utf-8?B?SnExYjZuTW9rbmhQdVg2SUR3OE40WVBKazREcjN3MC9rS3I0UW0vZUFyU2VH?= =?utf-8?B?Z3oyZEh5M1dHY25KaUV3eWhsK2hGeHZaaXlmTmp3emtJRE9qdVhTQT09?= X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-Network-Message-Id: 11f0bc16-9846-40ef-14bb-08dec5f923b7 X-MS-Exchange-CrossTenant-AuthSource: BN9PR12MB5259.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 09 Jun 2026 07:31:37.1187 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 3dd8961f-e488-4e60-8e11-a82d994e183d X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: XGXl1dX1nRRaLb3kA8D7eG/6xCmtbtxpyDfRy6YN3CxPLzK8LkiydoiOfEKnw7u3uzuYP6Mg6m63wts2FuGq3g== X-MS-Exchange-Transport-CrossTenantHeadersStamped: PH7PR12MB6489 On 6/9/2026 5:30 AM, Karim Manaouil wrote: > [You don't often get email from kmanaouil.dev@gmail.com. Learn why this is important at https://aka.ms/LearnAboutSenderIdentification ] > > In my opinion the driver should be at drivers/dma/dcbm, other DMA drivers > in the same directory like idxd and sdxi can just export a struct > dma_migrator. It makes it easy to have everything in the driver's own > directory. For example, idxd has some internals headers as well as an > already existing dmaengine implementation in drivers/dma/idxd. > > PS. I am writing an implementation of this based on idxd. I'll try to > post it soon with numbers. > > You can add > Reviewed-by: Karim Manaouil > Hi Karim, Thanks for the review. I'm excited to see your idxd based implementation. For plain memory to memory copy, which is all migration needs right now, the public dmaengine API is good enough, and idxd/sdxi/ptdma ... can all work through it. I'm curious which features you're planning to use from idxd internal headers that dmaengine can't provide? Also, my understanding is that driver/dma houses DMA providers, whereas DCBM would be consumer of DMAengine APIs. So is that right place for it? Best regards, Shivank