From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from NAM11-DM6-obe.outbound.protection.outlook.com (mail-dm6nam11on2079.outbound.protection.outlook.com [40.107.223.79]) (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 313932874F8; Mon, 19 May 2025 17:05:26 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=fail smtp.client-ip=40.107.223.79 ARC-Seal:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1747674328; cv=fail; b=cHQ7I6tCHrD/GfAWh1AbZO/ZFeWSgEFxdP6hquyBpxlWZQ76mk+2+tEhe0YpX5hYeMU+onrYUAyY+c4vJ9xL2b7pTlfID8TdmNx2H5zX1E8A00c949mTm4u5p8exE4xoUtO9q5wAIHXH4j1ZcXn8SbkZXYap67nDQl/SN5cO++o= ARC-Message-Signature:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1747674328; c=relaxed/simple; bh=+gaZCykeH3Ve0bDCDh2ARCsolM3rpSiZEk+eqt19L5w=; h=Message-ID:Date:Subject:To:Cc:References:From:In-Reply-To: Content-Type:MIME-Version; b=qFMvse/sdbVPkMVRB7tjFPe0jnK5ZKWqPnLs3oUGYMlulZkXrrGRPsjLRNBvWasrmFG2Vq+swc9oQustjumPN4BOVlMr0r7U93Qtwe8UthQZZJ+61C2DFgLRtc43r/R+Y7nRpTgDwPpjRP4PQy4WyuKhSq+ZB1lCOOqoz29TFKE= 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=mKt5Jq25; arc=fail smtp.client-ip=40.107.223.79 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="mKt5Jq25" ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=s6hB6TVg9t4Xz0UHrtZqrPOqrZxNPdDQAM3MaM5feQrmbDnsGbEmdIgLbrTyFCoXoH2nWNu+uHpt9FZwTV6/jbLrSSkBDzQOZh+wvjVzI5t8lRSZLcZz9OErb+qrRE7cQQ7JyW8xyQYKj4Xhzb8i2XHaIauMsUzDwtX/I7zU8NY4w0SX+d9cqK3OIBZHHWE2pstpKBeAvySRyPjDkYLkAWJZf2te2c0FT+9rKY7I+cEZ3pmCwKMirnNXKn4ylwzwBb0d4462g3diIPoqp1fBX6mabfPDtZ8u7dd4O7cyI0a4OEl0fAxhF5+LhoIa/OIgPd2HYMGM1KmOhYPBmls9ZA== 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=/5BArQx0hRBlgBGAB+Rnop+oLO8pn80ii8FzIJcNt34=; b=mXA6lbh7QwES/c/vXLw689iIPq5m0tiXthhU5ZXG7O2hlDMFMft2wTQzizs8asr/mo8ZqO5XjQu2GVogvt02lA++MLDzkmZ/XjciAIJjOwmPmvsoOQDiJN7F/rMKogy2fJqM9pl4T2Ndi8trhjyIoJ54/y/+s6uiuHVqMkUCx0+Au1svPohxZnLORvjN99OZcppmho261fDCiGXVCZJv3/MDglc75W6RAqT5afmIdbHABEFLJtowYf10Q0uCvCkcxuiwXQ5Hs8KuBPv/JKXN6DREa9kY/Yn5oYe2Uxpacvtyaa/ANFq792SKtmsUyoqezcIDw1DfCFjId8nlsZOrUw== 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=/5BArQx0hRBlgBGAB+Rnop+oLO8pn80ii8FzIJcNt34=; b=mKt5Jq25UUKZv0FOwdBEvEYRiTate9lHoYyUhcgkaUSMYwQR17iPcj4gmLJri2yB42f7DvyhIlxq7nHkVYGPTo6ChxOsHfSWMfYs2m+/kDC/RT9sd1qlRA40r6DGNCZD18/WQ7FpkMzflW9lPTNSlsHftnTv3nwqhV4thjLx1ZY= Authentication-Results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=amd.com; Received: from IA1PR12MB6043.namprd12.prod.outlook.com (2603:10b6:208:3d5::20) by PH7PR12MB6540.namprd12.prod.outlook.com (2603:10b6:510:213::14) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.8722.33; Mon, 19 May 2025 17:05:24 +0000 Received: from IA1PR12MB6043.namprd12.prod.outlook.com ([fe80::73e4:a06a:f737:e9be]) by IA1PR12MB6043.namprd12.prod.outlook.com ([fe80::73e4:a06a:f737:e9be%4]) with mapi id 15.20.8746.029; Mon, 19 May 2025 17:05:24 +0000 Message-ID: Date: Mon, 19 May 2025 22:35:11 +0530 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v4 10/23] iommufd/viommu: Introduce IOMMUFD_OBJ_HW_QUEUE and its related struct To: "Tian, Kevin" , Nicolin Chen Cc: "jgg@nvidia.com" , "corbet@lwn.net" , "will@kernel.org" , "bagasdotme@gmail.com" , "robin.murphy@arm.com" , "joro@8bytes.org" , "thierry.reding@gmail.com" , "vdumpa@nvidia.com" , "jonathanh@nvidia.com" , "shuah@kernel.org" , "jsnitsel@redhat.com" , "nathan@kernel.org" , "peterz@infradead.org" , "Liu, Yi L" , "mshavit@google.com" , "praan@google.com" , "zhangzekun11@huawei.com" , "iommu@lists.linux.dev" , "linux-doc@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" , "linux-tegra@vger.kernel.org" , "linux-kselftest@vger.kernel.org" , "patches@lists.linux.dev" , "mochs@nvidia.com" , "alok.a.tiwari@oracle.com" References: Content-Language: en-US From: Vasant Hegde In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-ClientProxiedBy: PN4PR01CA0011.INDPRD01.PROD.OUTLOOK.COM (2603:1096:c01:272::6) To IA1PR12MB6043.namprd12.prod.outlook.com (2603:10b6:208:3d5::20) Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: IA1PR12MB6043:EE_|PH7PR12MB6540:EE_ X-MS-Office365-Filtering-Correlation-Id: 87102a01-aa2a-4805-c279-08dd96f75841 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|1800799024|366016|376014|7416014; X-Microsoft-Antispam-Message-Info: =?utf-8?B?RDRxKy95OHlacEc2eWlvZ0ZoQVlvZDFYcFBhN1FjWFphTkxCYnkxRWFOZDRm?= =?utf-8?B?dkNyWHJyQ2YrcjBRaE9oOUljai9CbDNmSjZDdFowc293UVUweHZEazdyU0do?= =?utf-8?B?eXR5bUZqbEo2RWpzMDRLM1I2SVJKZXRMY05XWnJFc3ZwK2xaRjZMU3VoVTY1?= =?utf-8?B?QU9pOVdNTG1uUXp6MHBtL1RicjlwQ1RwMEJQSGZGK2lYUXdyQzRYb3l2VVQ1?= =?utf-8?B?ZllFYUVrd1praTBXRzNxUnVDbFlxM1dmbFVPUGxhb0NYMFlkQkM2YkZjVlFp?= =?utf-8?B?cmdIQm1sUDVjbWV6dFF6MGtTSDNWYkoyTFV4RytQQlFGNklkSVFGT0d1MmlQ?= =?utf-8?B?YzJNUGhTL2ZHOFhHYXcvWkpuODBSY3BDdTArMXRGWG1FTmdjYTRIc21hZnpS?= =?utf-8?B?elZuNlo2bWZOTFFTeWN2ejdFZHVVWnd6NkhRc3BzWVZ0bVpFSm9VZVVldTNQ?= =?utf-8?B?SFphWjBiZW45Qmh6cld2VlBDMUF3RlJFU1hXT1VNYkllYWtXSStVcGRlaW1Z?= =?utf-8?B?ZVlEL0tZS2NRbk5FSG1MVldLWFZadmcwZnMvelArdkJaK1ZOMlMwbjYwMWFL?= =?utf-8?B?dEZnNlFmcVZCWWdXUlVXMjBSZWlaNlRlaGYwSjZNZ3Zyc2JGbTkrVG81MEwz?= =?utf-8?B?VFN1YzhVSHo1OS93WVdFRlBvUTg0Smh3L0hySFJBdHRsQk4yYXdWZEJyMFF3?= =?utf-8?B?dEFCazJ6cXB4SGtpUFZhR1JWQlB4UE1wcUZuOThEZThlaUZaa0l6czRoaUtn?= =?utf-8?B?ZGhHTkthd0R6UEN4WFplV3cvZHBXdVRlMDl6bFZnZWRSN054dHIzV2MvWGlQ?= =?utf-8?B?NVp5QnFUcjFibVd6TUc1RjRsd0RvSXE2TTJBRXlab2k4TzNnWFRUOEVobmph?= =?utf-8?B?UnA5dEtNcEg5aGJJVWxucndBenhnUTBlMTZDZTRhT0pVc1pVa0tRQ0U4c21G?= =?utf-8?B?aTd5U1lqT2ZZeFRXL0VqNllCVDUraThmUHVaTzM1NTAwUjZuTUJ5bWpSZnpZ?= =?utf-8?B?VGMyRmRHWHJXZS81V1RNeEJUbUJkZFRoZVpDRGg0MjVUNm9pRkFoSG9hQ0ky?= =?utf-8?B?OGpHZ3AydU5nNklad2VvVXVwUFZMMWh0SjhxdWxkM3VrK3lRUTVIUnBKaFM4?= =?utf-8?B?bnJ3SjI3VCtTMG5tNVdqUHYxbzYyaXdyUmtSbmpzNW9xOW5rQXdpd1JYWUtl?= =?utf-8?B?bFMyNE1WWkUzS0JLV2dIbkFaeUVVVWpqaVhaWDVoVGZ2UU8xdDFaUEJnRGE3?= =?utf-8?B?ZTl3ZnlWNjNkaFdGUGlsSVVPRmRBbDFITjF6bDRxZGNDQjAybXJ4Wnl4QWpB?= =?utf-8?B?QTFDcENpdk1rNUJ4SDJ6TFIwTmhubWtiSElkeklYazI4QVEya1NUeTdHN0Rn?= =?utf-8?B?RjhicFEwSTgxSUNDdDFRQWRySkNUcGV1MmladFB3bExKVXZTTDQ1UnVQbkg0?= =?utf-8?B?bmppUkJ0YThwVHJjNkZEWUFtTGszM3J1dTFSMDdJNU5CYUJNWHZwNWN5bklW?= =?utf-8?B?Qy9zTTk2bFIvYTQ2bGNnRWs2L2xMK2xtU3JWTnhRd1dxc1VsMDdlS2FudlZD?= =?utf-8?B?NEJNa0dDNDY2WFZKUnRJMUxrWmlTNTc3dlVPVlJKdm1EenY2N1NkUEczdVZG?= =?utf-8?B?NWxZc244RFhJVGYyV0Zyc2lyQ3NuWDgyWUh2MmV5cTVsbys2dHA4N1RuRzJN?= =?utf-8?B?a3UxbXl4YW1VRjQyVW9JS3hpV0dJdjAvZGovTUFwRUtTR2pRQ1BiamVFazVa?= =?utf-8?B?NHhlSjF0Y1R3VnZnblVCSnpEaGlQQmdEVVU4bnovbEU2WlBDWjNMZmxGNWlQ?= =?utf-8?B?OWp5Nks1c1MrUEF0SU5aSHE2UGJPWGdWR0ozMCs0ZkQ0RFlXNDA1VGtpSnFv?= =?utf-8?Q?Jbeo6UvO49BXL?= X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:IA1PR12MB6043.namprd12.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230040)(1800799024)(366016)(376014)(7416014);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?utf-8?B?M3lnbHVWK1NBQ0xTNTE4VkwzOHY5SXRyUmpacnFaNERHVUlWVTlzK20yY2N4?= =?utf-8?B?L1p3UmV6QXgzeHRVMHU5SGVuNFRyOE0yUW04dktwd0hEYTB4c05PZWFCVVR1?= =?utf-8?B?YnYrUEtVN0ZlbFJ6czR3eUs5Ty9uUDFrWkRmVC9qNTRtaUxlOVpZc0E5aHR3?= =?utf-8?B?TTJlRnJMVUJVYUo3OUloVlJRSVR5SVdKS3ZiSGpjcmhIa0lSWFhwUW1QY0p0?= =?utf-8?B?c2lURlVONHdPUjRQQjE2cyt6OElpYTF2OC93MmF3ckVwMGZuOFpsTVhTSGhs?= =?utf-8?B?ankyQ2J6TUs5eDVPYS9pbTRGZGg4SXlKK3AwdEJ6Z0hpNEQwcW1aUERJdURx?= =?utf-8?B?NndrWiticnIrQ1pNcnJneTlrTVZPWTl3SmtQZEU2UHFsZS9zZndBaXJjc1NG?= =?utf-8?B?Y0syUmxDK3h4aTVyR2hOYnRkWkhVaDhGRnJBamV2dXRETFd6b0tOc2laVzNz?= =?utf-8?B?VFROQWxyRzNMcm9jQ1hWWFdpTUVyU2lrYVN4dFhLVFlLeENsUkgxOUdKck5L?= =?utf-8?B?d2R2ZkF0NzJXV2o4YVFnZTNoVXJVcW1Xb2tuL0paNm5IcllZM01tam9TelVM?= =?utf-8?B?YmJET3BncFk1dk9iRU45S1JVVWdGNDFWMzNucnREMldKb0JwSndIR013REtv?= =?utf-8?B?TGJNUEphc2ZMOXRHTkI5RnJYUzR0U1orUU1TVnVMNzcrL1RLemhrKzdybUlY?= =?utf-8?B?TW9jN0o3MWFRL2VHZVNsMHBzRFJRZmt0ajRPUitpOGUvaW5pdnhxWWlwdWo0?= =?utf-8?B?dThWcStXVG9qaHNDb1VkeWNtRVVKSjdxVmo2NHluZmlkdVJRM1J1T3NGNklM?= =?utf-8?B?V05BcmNxL2lWZnNBbmZFL2w3RGltWERrZWpRYU1BbnZnVFJTUmJUZzdrSmFQ?= =?utf-8?B?dmluaUR0d0p0RzRRRWxwQUpCTWJnVGtoaUNwV0dxaXFSYmM0ZFVnOUJKbnZ6?= =?utf-8?B?cnM5cVBYVWtSaXl2bDJvTVFQdDZMK29idEdabmhXVFJld2hNMmN5Q0hKd2hp?= =?utf-8?B?TWhTTHVxNEZ1MTZTeG1kMlNHbU8yVHpacUZlc1lBT3NyMWMvRHR2b1NteUpV?= =?utf-8?B?cFJqSUdpYzhGcEYyYm1rNVFFeHdYbHB4eFBKOHowV0RLVHprY1dlYUJ0amo3?= =?utf-8?B?R2pHU08zaVhyZkxORG9wK3oxYmFRQThYdFlaOUFNbEp1MUxYclJOR1k0Mmpz?= =?utf-8?B?M0FhMk8rQjNwTTh1amQvb1pSbDVMNkN4VzNjWGQ3dUFISkNMd0JhNVlGV1Z0?= =?utf-8?B?dXpCYW5jdmMvR09nUm1ZM1FrdVBGa2tGb3ZyMHdsV1FZU1Y1WjNLT2pOTnY1?= =?utf-8?B?T0taVGNUZXExMVpLOGllQy9BR1g1cWM4bkZOdDJOQUdTM0dlV3BScitPY0Fo?= =?utf-8?B?QnpQWWoxSnpORnc2Ulp0ajJNOTJsSGVURVA1Q2hwZ083Ym1FUzUxQ0p1SU9n?= =?utf-8?B?UG1tN3VFMDBMZ0djcnhqQ0E3anBGY2ZuTEZXbnJmWkhjNWFlWHVJOXJhNFhp?= =?utf-8?B?R3hLbnNuY1pZRW9KMmU3QUhJdEY2OUhkaGJ5UE9FbTZGL2tpb2QzSmNkOUJW?= =?utf-8?B?QUxReER3cE1NWUo4SzVINkVWREZIdXk1UEl2VHVlaHBDRkg2NWcyR1BjcVlK?= =?utf-8?B?S3BmUnY0MEp5ai9iNUxsdmhQbHM2Q2JJcUdhTzAyRm5rZXRYT1VYVnMrUC9h?= =?utf-8?B?WC9kaFZxVmtYbFB0Y3JlUnRqdWRoaVFqa3VEUnhEVWFEZUZnb0Q2UGFKT3Nt?= =?utf-8?B?ZXRJbGpnSmtHb1NlVmFwQmlUQ1V3Vk84d0MxaSt4L2pieDQyUTZzSk9NT1E3?= =?utf-8?B?dHNDMHpMek56V0Z5R2lnOGVCbkpFN1hvd25RYW9mN20yajNLQ3pVM0poV1ky?= =?utf-8?B?Y3FyMzRleHdDUkd0aEVUem5Na3I5TGQwVWVScFRzNVlJUUpPYWxRTkhGU0w5?= =?utf-8?B?d256Q2xnMTNiQldtNXlNZVAxdjlmSUZNQ2w1NHl3bWgyRjJHODVpa2hhMnB4?= =?utf-8?B?SjJoU1RmUGluK2NOcVQxSXRBZ2xzOXRPNHlwdVpHdTdlUTA5UGFmRzNkaTd6?= =?utf-8?B?N3ZSWXliWmp6b3RNZ3IzQ00xOEVKeDNkdkxJSTl6TDFRL20vb1BISzk4Wm4y?= =?utf-8?Q?Afr27TJyAi0ne0y4YLc4e14CE?= X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-Network-Message-Id: 87102a01-aa2a-4805-c279-08dd96f75841 X-MS-Exchange-CrossTenant-AuthSource: IA1PR12MB6043.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 19 May 2025 17:05:24.1841 (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: +6paPEi7pG64LXccT4GlfXsyGMpp18+KJr3HFvBS5MaT7DSKxBpU1bXYBSrH0/b/HzS9wAohgH45CF0Vt7a1Lw== X-MS-Exchange-Transport-CrossTenantHeadersStamped: PH7PR12MB6540 Kevin, Nicolin, On 5/16/2025 8:29 AM, Tian, Kevin wrote: >> From: Nicolin Chen >> Sent: Friday, May 16, 2025 10:30 AM >> >> On Thu, May 15, 2025 at 05:58:41AM +0000, Tian, Kevin wrote: >>>> From: Nicolin Chen >>>> Sent: Friday, May 9, 2025 11:03 AM >>>> >>>> Add IOMMUFD_OBJ_HW_QUEUE with an iommufd_hw_queue structure, >>>> representing >>>> a HW-accelerated queue type of IOMMU's physical queue that can be >> passed >>>> through to a user space VM for direct hardware control, such as: >>>> - NVIDIA's Virtual Command Queue >>>> - AMD vIOMMU's Command Buffer, Event Log Buffer, and PPR Log Buffer >>>> >>>> Introduce an allocator iommufd_hw_queue_alloc(). And add a pair of >>>> viommu >>>> ops for iommufd to forward user space ioctls to IOMMU drivers. >>>> >>>> Given that the first user of this HW QUEUE (tegra241-cmdqv) will need to >>>> ensure the queue memory to be physically contiguous, add a flag >> property >>>> in iommufd_viommu_ops and >>>> IOMMUFD_VIOMMU_FLAG_HW_QUEUE_READS_PA to allow >>>> driver to flag it so that the core will validate the physical pages of a >>>> given guest queue. >>> >>> 'READS' is confusing here. What about xxx_CONTIG_PAS? >> >> Combining Jason's first comments here: >> https://lore.kernel.org/linux- >> iommu/20250515160620.GJ382960@nvidia.com/ >> >> So, pinning should be optional too. And I think there would be >> unlikely a case where HW needs contiguous physical pages while >> not requiring to pin the pages, right? AMD IOMMU needs contiguous GPA space for buffer (like command buffer), not contiguous physical address. >> >> So, we need an flag that could indicate to do both tests. Yet, >> "xxx_CONTIG_PAS" doesn't sound very fitting, compared to this >> "IOMMUFD_VIOMMU_FLAG_HW_QUEUE_READS_PA". >> >> Perhaps, we should just add some comments to clarify a bit. Or >> do you have some better naming? >> > > let's wait until that open is closed, i.e. whether we still let the core > manage it and whether AMD requires pinning even when IOVA > is used. I think we may still want to pin those buffer address. -Vasant