From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from NAM10-MW2-obe.outbound.protection.outlook.com (mail-mw2nam10on2044.outbound.protection.outlook.com [40.107.94.44]) (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 E93F7944F; Wed, 5 Feb 2025 03:15:25 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=fail smtp.client-ip=40.107.94.44 ARC-Seal:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1738725327; cv=fail; b=ZMHwIsEAw7523uDWNCSlbzkx75V7//UhYC6uKr22G0WbUtkIVnF1MDMopumvydrolzxCnMdM2+KZQ4lf6ZI3LdD3k+m9WzfIxqFiLDqlcntzgtqCRmFw6sWNOHKcsjAPqXYrvgloXnLn4SDde7Z8zc+zH/jcJbGxhwVujUFdx6U= ARC-Message-Signature:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1738725327; c=relaxed/simple; bh=pEiFF+rsnyJZZvQoZJkpbYP3ABiw/IZrIcE57mAfqP4=; h=Message-ID:Date:Subject:To:Cc:References:From:In-Reply-To: Content-Type:MIME-Version; b=HJ8L8Z0Ja+N7b1lOXH/cjLuKxr4emBeWS22EhCpTLDC6lwkWsEtv9OyOzUlb7NwOB4SDmAlHx/s45UlhbkIvsyjLKbgJHiMW59vV8YPDdoGDYpmNONtF99RlGyQraECBMVTtkWE1+gKGG/duBS+WNbte6Cbcpt1cMOvN2AOKQUE= ARC-Authentication-Results:i=2; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=nvidia.com; spf=fail smtp.mailfrom=nvidia.com; dkim=pass (2048-bit key) header.d=Nvidia.com header.i=@Nvidia.com header.b=ebdonI7f; arc=fail smtp.client-ip=40.107.94.44 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=nvidia.com Authentication-Results: smtp.subspace.kernel.org; spf=fail smtp.mailfrom=nvidia.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=Nvidia.com header.i=@Nvidia.com header.b="ebdonI7f" ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=vQNqwOkJdOdFIteq8LQVakqQZhlOiUXuXZ1AbFIkvuXmDmYkXm+TF5Dgijgx9GU0AdSZz241gT3E67mNmDi0IXkYz+vP4M+D9wd4cF2NGvP5I4UNFcGaRiC4pqVMYQaSTATqdDhAZIkUppWF7hW2AmwK0b0zSyLJki9PohK8rJaMO9TLMve1WJmVkvK/hHLgDxUmbkF8UBu3Sj49URavRC4tDjGXKLiq4B9JxP/+JRyo9/MXnq6W2gcOmXE9LvDcb3Lap8ePMnGwhSXvs2CjIRK+9189tXydRzMNCG6VA8wgi03SBuuYuxbrFEdPLQuUXRzcOe7JRfGh3nW+aMM29Q== 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=+XQPjqiXJppbtW8hBGh+rQjDNDnhYxDnte7JvurJ7t0=; b=Kk6X30ioIwhq+RsOnbRbQywxNVm8p8N8v/bdfpq3Xqee+n2Nx7ZoAL0lQN1cWmEeod3TnkusRA21uCR3+za4uuvDm7W5y08K/hLlE0FcKO1LExdbazzMAIq2W/mqrB/jFvxylnUQIeRfWWvucnGh/o97fxzjQlRv88Mvods66wMhycvJS2hm/+Io09dJ7ODPBHZfWtYN2armxMPV0awZn/00PH/XArN/avzh7vrIA9VhLGaCLDdlRjjDM7FMgd/eLWqpG6J563LyLTRFC6UGYVE3I8lMPlbmHcz9Tu1wP11K+LwukT97GYj/jAFZZd/PPuEdXIwOBxSMfzTrUCdjdw== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=nvidia.com; dmarc=pass action=none header.from=nvidia.com; dkim=pass header.d=nvidia.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=Nvidia.com; s=selector2; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=+XQPjqiXJppbtW8hBGh+rQjDNDnhYxDnte7JvurJ7t0=; b=ebdonI7flGzlG/zAVaIK+bBEjdqWAbIlFRci0VWzQJV3TvYNbbmUv0qFxjCVVAQsfqOusbks1sf9WnEmxBV0bobkpA8w2FBsfyOKcwVqv+6M8054dltxUVvh082u9ENYuSCjiwbpXn5ibR7tKMqq88yz5dBQdOG34FuR0+lIMIkhUo5VzsaIToNCf6LW2GQxabzv24Z1TN7JLUT7tBplQugTuBlfNPhH55oG9uLjOUcMtLTXiivWPUo9VBfPi4aT0wYJkveaG93g7sORYZbkY2xVcZF1BVGqIMMl5OQws/Yy2V63AgqpwsKDql8aSo/1st+frfPd1+EPUwUD44i94g== Authentication-Results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=nvidia.com; Received: from SA1PR12MB7272.namprd12.prod.outlook.com (2603:10b6:806:2b6::7) by CYYPR12MB8869.namprd12.prod.outlook.com (2603:10b6:930:bf::8) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.8398.25; Wed, 5 Feb 2025 03:15:23 +0000 Received: from SA1PR12MB7272.namprd12.prod.outlook.com ([fe80::a970:b87e:819a:1868]) by SA1PR12MB7272.namprd12.prod.outlook.com ([fe80::a970:b87e:819a:1868%7]) with mapi id 15.20.8398.018; Wed, 5 Feb 2025 03:15:23 +0000 Message-ID: Date: Wed, 5 Feb 2025 14:15:13 +1100 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v7 02/20] fs/dax: Return unmapped busy pages from dax_layout_busy_page_range() To: Alistair Popple , akpm@linux-foundation.org, dan.j.williams@intel.com, linux-mm@kvack.org Cc: Alison Schofield , lina@asahilina.net, zhang.lyra@gmail.com, gerald.schaefer@linux.ibm.com, vishal.l.verma@intel.com, dave.jiang@intel.com, logang@deltatee.com, bhelgaas@google.com, jack@suse.cz, jgg@ziepe.ca, catalin.marinas@arm.com, will@kernel.org, mpe@ellerman.id.au, npiggin@gmail.com, dave.hansen@linux.intel.com, ira.weiny@intel.com, willy@infradead.org, djwong@kernel.org, tytso@mit.edu, linmiaohe@huawei.com, david@redhat.com, peterx@redhat.com, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linuxppc-dev@lists.ozlabs.org, nvdimm@lists.linux.dev, linux-cxl@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-ext4@vger.kernel.org, linux-xfs@vger.kernel.org, jhubbard@nvidia.com, hch@lst.de, david@fromorbit.com, chenhuacai@kernel.org, kernel@xen0n.name, loongarch@lists.linux.dev References: <23432568750f099d32b473f64b7e35f0671d429e.1738709036.git-series.apopple@nvidia.com> Content-Language: en-US From: Balbir Singh In-Reply-To: <23432568750f099d32b473f64b7e35f0671d429e.1738709036.git-series.apopple@nvidia.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-ClientProxiedBy: BY3PR05CA0047.namprd05.prod.outlook.com (2603:10b6:a03:39b::22) To SA1PR12MB7272.namprd12.prod.outlook.com (2603:10b6:806:2b6::7) Precedence: bulk X-Mailing-List: linux-xfs@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: SA1PR12MB7272:EE_|CYYPR12MB8869:EE_ X-MS-Office365-Filtering-Correlation-Id: 33aed631-0189-46b0-8b35-08dd45935472 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|366016|1800799024|376014|7416014; X-Microsoft-Antispam-Message-Info: =?utf-8?B?SlRxWm9iakpaY2FvcHE0M21BRjBRWk5pcmdUR3ZLci85YlBOWURNNmVkQjds?= =?utf-8?B?VDU1YlBwdWJaN3daUnZjc3pDTmxpblYyZ2pOY2dBM0xPTERvL1BwU2x0aHZt?= =?utf-8?B?VHFaOGd0RS8yZmd0RjlaQXlJdkoxcGxSSjcrRGNUQzJuekV2U1J0STFDZFhl?= =?utf-8?B?QjhNdENGUnNWZy9RcFdob1hxelRWQmJMVVVGcGdPUVN1c3FOMDh2citqaFdF?= =?utf-8?B?RGt3TFhwRy9ZTC9HbmZoZlZpNTVKZENCUGE4S0JnNUZCNlZYdDVEK0xJZFV3?= =?utf-8?B?U3Flais3TjdlOGRSN1ZVTkVpbkRtQ3JldU9tN3RDK0pNWDRSczl6RUl4cDVJ?= =?utf-8?B?dHdhdDlYS2hEUnRnSDFSdnFwZnVjZmxYTUFkcy9Jb2MrZGF4TlR2RHdwKy91?= =?utf-8?B?elcwb2FURm42K0ovTjhBcFdsd2I3b0JsTTlscVVRWXpOaEVFeHYyMkJlZktB?= =?utf-8?B?Ykk2RWlHN05lRW9YZFgwdm1vd1ZJQVNmSGRpNnhhWC9NWXRSVnBHRXFHNWJq?= =?utf-8?B?UU9OUGFRVzNUMlVFeFBxNndpQkdna0E3V3NPLzBoeVg4RytjOHY5SW9ta2hL?= =?utf-8?B?TEE5NTVvdE9uakJXRTZOVFlsM25oUkRtOWpIYWRyUTFCNmNnYU5pOEdhRFd2?= =?utf-8?B?eGdhOFcwK2dWK1lTZlFIeVl0TU1OWXNlcDliNTk0THByQi9mV1hveFJOcDU0?= =?utf-8?B?TGVlKzJwSExOTkNlZ3ExbXR5MTNZS2xWOXgvSi9NSzd5L1pMaEZxaXZmTlEr?= =?utf-8?B?Q2RpcEJsOGU5eWppZ0p4ajU2azhhdUcrQitFcGJRN1FaV3M5WTNRRTNMdkpW?= =?utf-8?B?bS94UWZBZnROVlgrQmhKMFdYcFhvc25XUURrQ2R2TU5zM1ZWV09nTWZBdHFN?= =?utf-8?B?eFZxTlZlc096RVhhZHp0TG9KYUhoZCtmWmpPa1U0aVhpMHlxc2VwUWpLdC9w?= =?utf-8?B?ZGo2Q1BleFJOVHRWNXgyTHVWNmdUTGFTaHlUVDlGYjVyZ3FESWNHQlUwYUNI?= =?utf-8?B?VmV2b29LS3JyNFVIVS82MWZnbDdoekp4UDB4V0MxVWpEdk5rSW0zSENueGda?= =?utf-8?B?WFZheUpQb2l6SWFiQWNraGJmVzNJK1pGU0RhSmxYeTkvSTBYUXdzejZyeGV3?= =?utf-8?B?QnR3TVBhRGRGNmZETGo3U0RZN2s2UHRZcmIyU0FUd0lIVG5rQzgreWZPUm9t?= =?utf-8?B?VE1LTjdzaUV0MEJ4aisxQ1FwM1hIWDlXR24yWnFuZFpEcktrVW0zRWo3VTVB?= =?utf-8?B?VmI1cnRXUm8xaXA4ekpqUlN6V0czelVYSkdsSmVySitZajNzYjNzVDJCeHhz?= =?utf-8?B?ZEpwdU5ISHA0UTNwZHFieFZudHBSTnlINTk3Tzg4MmdpbGg0Wi96SjUwYitv?= =?utf-8?B?RTJLRkYyUTR4NVk0N0JIeXBESEh1b1l6ODUyRUpVdkw3Tzl6cDZzWUpwOGxR?= =?utf-8?B?SkxnNnR5Z1pJMFRMREExNjJUaE55QVBxdDlsN2E0UTVrWk8xckxNcCtrU3Fs?= =?utf-8?B?Njl4VTFZTFpUcXVGa3czZHVKR0Z1U2pvREpnTWtuNFNPaGdHbjErSkNxOHpJ?= =?utf-8?B?ZVArS3h6S3UzVTRlQm9JOUdRems4UWpKZkRUdFBFS05KTkM5cHRwWDBUbisw?= =?utf-8?B?SjVsQlYxdGZWdHRkaTdTZmQvYk9GUDJBRExUSlJxNzJFeThIQnRYdXgrVGdF?= =?utf-8?B?Tk9jSXRtNEVXUkRwd0wwNURFcjg0L3ZFaEpxOGw5UVBqVXM5V3BhdFF2Mis2?= =?utf-8?B?ZHc1RUJScmtNUjBCN2NVZFJwNFNWWDIxV3hUUVhZSUF5UjZRWmpoV3c2N3FE?= =?utf-8?B?Q21YS1RnSy9FV0VvTGpTQjFYbW0xdmNtaFo0T2Joa3BndHdRcWRpOHdyS3Bq?= =?utf-8?Q?/NxUwHAF0fs9I?= X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:SA1PR12MB7272.namprd12.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230040)(366016)(1800799024)(376014)(7416014);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?utf-8?B?TERFZmVZY0UrcGU3RU5xcyt2S2pNMWJBUC9kZFphZDVYakdSTmFxVkpBa1Nq?= =?utf-8?B?Y2p5NHo3d1QyTUpnYWF2UlR2Y0hvL2FVWTZkSkNhdWhvUk9GQlQ1SEJGUFpW?= =?utf-8?B?ZitkVUhHN28zQTdDd3ZvY0NCU3h4R1BFRklSS3plU3dVTkhNYyt3Uk5uNHpu?= =?utf-8?B?WC80ZFNuNng4cWpyT0JaWHhzdFdFMXFYRnNtM0lSWHFhR1V2MzVINEo5R0Nq?= =?utf-8?B?bTlWK0tMNk42dWFQQ0l1ckhmcEkxUVNoVzNOWElHczhsWmJQR3lDQ1BOOWMv?= =?utf-8?B?VnN4SFFLOGxZNW5DTmFMNm5wMEhqYmVCK2oyTmJ2ZGFnQTd6dHZmT1VLL2VR?= =?utf-8?B?UUJMS05jd1ZBWmtUbWNHazdNNDVPUy85SDBOUEo4RS9pL09PUjNNbmJ3OGhC?= =?utf-8?B?V3NHYUVSUVdzbFZPTUdLalo4OXJCWUdYdFFxbkNhL2FJSGVsaVFUSFlkc2lm?= =?utf-8?B?ZEtwUTh1MmhteUhBVFp1cGYvRG5KZ2FGY2tVc0dkV09tNDMxZEh2RE9aenhs?= =?utf-8?B?Y3NpTkdvS0hWTHNkeEJXR2dLK3hHcFpic3JCNE9PaFJkei9jSjc3KzhCNzhU?= =?utf-8?B?TmxZV2JmUzkzblphbnMybldVSTBieTVOSGJ1Q1VXWEpjWU9xRmZzektoaWtr?= =?utf-8?B?TWk3M1NMWTUwckpFa1ljOERtUUJHNkVOdkFLUWlLTThPa0JUVm9SM3VHOWRB?= =?utf-8?B?YkZVQll5Q2dqV0FoM1JyVEYyZ1dwVXdBdStucjAvblRpZUtkYzhVT2RhVkxF?= =?utf-8?B?ZEJCUFYzZFBaTkRjRTRtK2taSmxJbUd1UC9RVWN3VVhkMTFrbnhFMGVIVlNL?= =?utf-8?B?aW9ScWRlVW1mRVZ1WEg1NVRQNFY0TExHcTl6d0tYTlByQTR6bzVBb2xzUjlX?= =?utf-8?B?YUlwZy9jNXlJWUFrbTNOWjZVOXBNS0l6T2szMTJrZU00RGlTekpUS3VvU1dP?= =?utf-8?B?aGVSSHJ1OGZZK0RkTFlFUCtWZmNKMW40SEZqeWhieTFrMUtlSmJwRVlKRFFE?= =?utf-8?B?ZGNnbmwyN2JBbXJiYlQrMjBBYjI3ZTE5TnJKNTljdzF6UFdxK2JMQTRqcVZh?= =?utf-8?B?a3pEdHllYlhWbEdKL2RpNGpkRHdWdGJsTGVHMVFzVGpjVi9mb3lEaWM5MnVp?= =?utf-8?B?TmQydXZWRWs5d2pZTkkvd3BWMDJpZFpyRXp0bzV3SEptbkMxek5EOHhVcHRp?= =?utf-8?B?STQ4djBuOUd1M1Q3MlBFYkFlcUlYMCs5YUZMSWpsSjR4ei82eC9BR2xveWJW?= =?utf-8?B?K0pxbEZBWFlseWV5V0MzdnZIOXA4bWVRNllFK3krblN4dVVVMmoralh1TjJO?= =?utf-8?B?TzFNWEhibGZtSTRNNzFTZElGTFJVbkRsOGRrUlQ4Ukl2QU93d1BhUzNQUmt5?= =?utf-8?B?cVVvS0JsbjdFNnl6ZGFOR29UUkRKWEJFYXNONWRwUEQ0YmxwaFNpaG1tTm45?= =?utf-8?B?dXFENUZJQ0diZWtGTkhiby9ZaytUQ0ZwMnhiOXJwWEtiaDArT2tlRFFZTEIy?= =?utf-8?B?Z0pYTnZzbFYxWk9zOHN4OVZpbHJQdGtmVWllQmM1S3NGeHNkcWdqekNaUE0v?= =?utf-8?B?RFUyb2IyK3dBeEZaQXk4TWJyaklGcW5jd3FPT2tGTUFobjlDaHltZnRNVVNM?= =?utf-8?B?dVBvWWszbGJOMnJabFlPZFZXaVYwbld6eFZ5eS9EWFByQ3lRVW5RTEZkWWcz?= =?utf-8?B?YXlzakdYdVgyYm5TZ2haQXJJcUJzNW00NnRudkFjMTluRVpDS1U3bUszVkNs?= =?utf-8?B?OTloYnY3NWhHVElrM2srbElKU1UvSUdJOTg2Z0NjcTBYQnZVMkhTNlBoZ2pn?= =?utf-8?B?ZDNiTG9iZWhhR3lOaUZHelRselVnQWdKN2hTdXJudVlhV05aTmJRbGtGU2Fo?= =?utf-8?B?M25yTzlVT0ZBWmRhQkllZmdpV0tIWDlVRUgyV1RNczd5R1pBd1NWbm40OW9r?= =?utf-8?B?c3BvN3JwRWEzRVd4THRXNWtNTFVSMGFaSGZOK1RoaEFDcHlWcVJNVHY0UE9s?= =?utf-8?B?UDMxZVMxMEZyVTZjSDA5aHdMRGRWTjNvRzVFRnRtaUlJb0lwMGlaUEhSVW5Z?= =?utf-8?B?dUlGNFJzY294M0h0NjNKN040bTBlR0xNaS84YXNXSXp6SmdSRFp2NzBLQWJi?= =?utf-8?Q?zFo1AQ55q5WssgJvJFxJH9ObZ?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 33aed631-0189-46b0-8b35-08dd45935472 X-MS-Exchange-CrossTenant-AuthSource: SA1PR12MB7272.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 05 Feb 2025 03:15:23.7299 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: j9mNCdT3kvaPRxQet1moohg9yeUlozD761HCXxdxaHduego9QnFRFYV7w9PmaxSZtmbXdlP3nhE63z4NPJkGiw== X-MS-Exchange-Transport-CrossTenantHeadersStamped: CYYPR12MB8869 On 2/5/25 09:47, Alistair Popple wrote: > dax_layout_busy_page_range() is used by file systems to scan the DAX > page-cache to unmap mapping pages from user-space and to determine if > any pages in the given range are busy, either due to ongoing DMA or > other get_user_pages() usage. > > Currently it checks to see the file mapping is mapped into user-space > with mapping_mapped() and returns early if not, skipping the check for > DMA busy pages. This is wrong as pages may still be undergoing DMA > access even if they have subsequently been unmapped from > user-space. Fix this by dropping the check for mapping_mapped(). > > Signed-off-by: Alistair Popple > Suggested-by: Dan Williams > Reviewed-by: Dan Williams > --- > fs/dax.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/fs/dax.c b/fs/dax.c > index 21b4740..5133568 100644 > --- a/fs/dax.c > +++ b/fs/dax.c > @@ -690,7 +690,7 @@ struct page *dax_layout_busy_page_range(struct address_space *mapping, > if (IS_ENABLED(CONFIG_FS_DAX_LIMITED)) > return NULL; > > - if (!dax_mapping(mapping) || !mapping_mapped(mapping)) > + if (!dax_mapping(mapping)) > return NULL; > > /* If end == LLONG_MAX, all pages from start to till end of file */ I think the patch should probably also add if (mapping_mapped(mapping)) unmap_mapping_pages(mapping, start_idx, end_idx - start_idx + 1, 0); But I don't think it's a blocker unmap_mapping_pages() should do the right thing internally Acked-by: Balbir Singh