From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.19]) (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 A898A18BC3B for ; Fri, 29 Aug 2025 00:45:56 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=fail smtp.client-ip=192.198.163.19 ARC-Seal:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756428358; cv=fail; b=EGpgbG28rTZpTSJwYjnY0a/ZPZcck4Cp6L5ZDu5uQ//zPx0FktqVOTHfthN9arVKiYwhPsiDRMqQt94u4i5mmIFHcMYgELp7v6XK7oEFFbxtcgMynymIr7n0uv0y9yOjjPmXLIjjRJndvambNkOYpREpVJf42QSi+uUA0HV/k5Y= ARC-Message-Signature:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756428358; c=relaxed/simple; bh=zmbA7d3e5WWyj/GYXUiaZdL3MNAalbvJ+XlW2cC1SSE=; h=Date:From:To:CC:Subject:Message-ID:References:Content-Type: Content-Disposition:In-Reply-To:MIME-Version; b=OEpUHjEXQDM7NlTvWelwRgLoNihA6/jRJWTBXK7JDg3blUn7+tO4f+9ZL4Qu3L4/VZRg9nRjgIrwK6NxKJiojn+R6zszIdhbJoL7xXco5yGk2s/MORXsbsDPoun1/JCmsYOincFC07jsVbd+Smf8d+kTMIuHhA8zOAhxRx1rEO4= ARC-Authentication-Results:i=2; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com; spf=pass smtp.mailfrom=intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=eljtRH1S; arc=fail smtp.client-ip=192.198.163.19 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="eljtRH1S" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1756428357; x=1787964357; h=date:from:to:cc:subject:message-id:references: in-reply-to:mime-version; bh=zmbA7d3e5WWyj/GYXUiaZdL3MNAalbvJ+XlW2cC1SSE=; b=eljtRH1SUyH6+3hGt/og7R0lq9xOdl3giXUUMygQr+q4k7AcllVRkupy hEUfMHizIQGg1ujxZE9uO8CljImplNxN72CuAnnVhbGqjyf8jwnnmyp0X AeRktuzk95lQ93VrXByQPfgoEci0U9brytePmRthZe1x7+UFAjUDenIRh 4jUvWy57F07NGu5Dzvq+9OVxoONYN6STpoX5DUni6YjZL6xeMxTxHraHY R7Vd5Lrbo3CPXT5bGqxR8Ben4W98HQiJyGvDzZIywSzOhsGt/pPJjLXjb mWCj134E++4PK9LDGcx3460xvVn8+NavE5oykefbH+V2vRk/zatxxPYl/ w==; X-CSE-ConnectionGUID: /IwKWddtTFCz1ngeivXurQ== X-CSE-MsgGUID: 1lYng74dRs2MqSxDasroKQ== X-IronPort-AV: E=McAfee;i="6800,10657,11536"; a="57738509" X-IronPort-AV: E=Sophos;i="6.18,221,1751266800"; d="scan'208";a="57738509" Received: from orviesa004.jf.intel.com ([10.64.159.144]) by fmvoesa113.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 28 Aug 2025 17:45:56 -0700 X-CSE-ConnectionGUID: bdu8e8diRU65YBMoM+MV8w== X-CSE-MsgGUID: YjISaN4tQa2z6XOyx2H4iQ== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.18,221,1751266800"; d="scan'208";a="174626621" Received: from orsmsx901.amr.corp.intel.com ([10.22.229.23]) by orviesa004.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 28 Aug 2025 17:45:56 -0700 Received: from ORSMSX903.amr.corp.intel.com (10.22.229.25) by ORSMSX901.amr.corp.intel.com (10.22.229.23) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.2562.17; Thu, 28 Aug 2025 17:45:55 -0700 Received: from ORSEDG901.ED.cps.intel.com (10.7.248.11) by ORSMSX903.amr.corp.intel.com (10.22.229.25) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.2562.17 via Frontend Transport; Thu, 28 Aug 2025 17:45:55 -0700 Received: from NAM12-BN8-obe.outbound.protection.outlook.com (40.107.237.75) by edgegateway.intel.com (134.134.137.111) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.2562.17; Thu, 28 Aug 2025 17:45:54 -0700 ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=eLRIvV5zKJ95SXs/ib9FirBmnwXioVn2jSNxylI5kFIulW0gza4hseKxyvEfdsarg4NOWkOPmhMhMLjtOhlAA1pcRFk9TbWsgr98yVfslhMNIbwgiVZB3iXmA78iDTuqZFnBfc2LHmvxItjTGURxshGHpmvDZS9oHx0H7rENhkmFryzwR/agXs3PkRD2Ik5I5FQ94nMgINGiJZDehwtgq2rOE3TYGr7A+K3qbZeIsFqHC0PQnmOhIJv/l4tvyyBVpTSacXHqWM5xugUwiOCc878a6zmCoqS0Aoc2KaxsszONw0BBKLoe6u/wlQf8XTMeTs4VJTa/KUMu2mFA9W61ZA== 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=k+9ILtX8tL3hpDeGUW0t8K2KJEefr91ZxTlfGpWbJ/U=; b=wLTaUrAcmmaqFy1UnJjfXRAMAoe65RDLS2eilGmQWNWCpvsfC1gxaIZkDR9LL0QMCt0ki5R5iUD01eUQg/wJI30aLJqeI7qf4MffQTUTUNEpkCjM+sAFEVdZL9CB3qpPsCPpHxYTQKfNDa/NlGsoXdNcxv2fnCnJwB5VVZ0pcdEwHhe8Tc3SMRWCnhtADe1EWA+n5MlAB4LxTr2+2HNsNFnu6307NV0OpjvN2Ei+AfZ1XBLk0fh3pHKPhMF3u3zBvF1GXaO5iQjA89tZJUvj5g6aVNlksJka7xxJN1tF75rAKKuBRVy6/EKXXMMmen3YxjVuuRVKUUXfSSmfE9eysw== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=intel.com; dmarc=pass action=none header.from=intel.com; dkim=pass header.d=intel.com; arc=none Authentication-Results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=intel.com; Received: from PH3PPF9E162731D.namprd11.prod.outlook.com (2603:10b6:518:1::d3c) by PH0PR11MB5175.namprd11.prod.outlook.com (2603:10b6:510:3d::8) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.9073.17; Fri, 29 Aug 2025 00:45:44 +0000 Received: from PH3PPF9E162731D.namprd11.prod.outlook.com ([fe80::bbd5:541c:86ba:3efa]) by PH3PPF9E162731D.namprd11.prod.outlook.com ([fe80::bbd5:541c:86ba:3efa%7]) with mapi id 15.20.9052.019; Fri, 29 Aug 2025 00:45:43 +0000 Date: Thu, 28 Aug 2025 19:47:31 -0500 From: Ira Weiny To: Mike Rapoport , Dan Williams , Dave Jiang , Ira Weiny , "Vishal Verma" , Michal Clapinski CC: , Mike Rapoport , Pasha Tatashin , Tyler Hicks , , Subject: Re: [PATCH 1/1] nvdimm: allow exposing RAM carveouts as NVDIMM DIMM devices Message-ID: <68b0f8a31a2b8_293b3294ae@iweiny-mobl.notmuch> References: <20250826080430.1952982-1-rppt@kernel.org> <20250826080430.1952982-2-rppt@kernel.org> Content-Type: text/plain; charset="us-ascii" Content-Disposition: inline In-Reply-To: <20250826080430.1952982-2-rppt@kernel.org> X-ClientProxiedBy: MW4P221CA0016.NAMP221.PROD.OUTLOOK.COM (2603:10b6:303:8b::21) To PH3PPF9E162731D.namprd11.prod.outlook.com (2603:10b6:518:1::d3c) 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: PH3PPF9E162731D:EE_|PH0PR11MB5175:EE_ X-MS-Office365-Filtering-Correlation-Id: f9063487-1937-4072-773e-08dde69562c0 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|376014|1800799024|366016|7053199007; X-Microsoft-Antispam-Message-Info: =?us-ascii?Q?t+g6/MWeXYtCj1R8vO1g9YtEwQMOxhPXWbyGrdgRPUzoT3CklMtj2ugq5AOY?= =?us-ascii?Q?vo1ZunBPCbasqjzPypcQy9EQ2WPw/77VO0MXSRYGp8P9weYQyAcoAmxM9npp?= =?us-ascii?Q?jN3BbRGH6hq+0ngB9tZOG4Q6M9LEzeTqtaBs4aJ4lTSe+kITXCoyaAF+EpeA?= =?us-ascii?Q?NESuuW6PInOQ84jSbGpBxHOSrKdrlVjtebsTIMxCsjFuP969odEj4pV/9dVN?= =?us-ascii?Q?E4appbfB8NdQx0eXe1Rk1BYWXBuEaI8uUJddPU+wKSsNyrcg1uv3rGOqPrf5?= =?us-ascii?Q?t3D3z8oRNhRThb66mLblZ/FHGp18rXCvdDyS54GQSPovEertCYyQQPoFMuXt?= =?us-ascii?Q?2Nqo3FFv0e7teDXau1+o22cpHNXChA3xZrnFAg+7iDzUZwsSVL/dMunnBXXk?= =?us-ascii?Q?9PtJ/FKeveNe19UPWPpzmHMTdEGfM034DwnEgLSl9aok5WcD4ly52b1Z6c1q?= =?us-ascii?Q?bcPfLa9NpetNnLq2fuPO9zXoQnyTpmxpsPlAipbv7I4uAeq34esYB/54cMUG?= =?us-ascii?Q?c/kbLAqkXDo+N41qSGWNtRgxKUgU62+l6Dvs0pJqp1jIcYkXMaZ6CHXuxwe2?= =?us-ascii?Q?XhGyVZWynq9fZ4Pu17TuNPQBtRqQhHhsRxAeq3g50squk+L+1XDiAAnJwkpl?= =?us-ascii?Q?9YjZvSBdFfzqmeIGQUkd5QrKzCfieiFZop/OTOtdD6xkU7Bpg+Vp5ryoo81a?= =?us-ascii?Q?61qAV1OZ+aNTHznZth1SlGb4lrw+L46AkbCCPw50qgv/bAiZxYgd5V+8ZOS0?= =?us-ascii?Q?6MyrwUHFP9/faIWQuaP6kKe0SNyEplNX9ASg4A5TZH3rg1XXKSq6lfTU66Wf?= =?us-ascii?Q?wjIFam8SO2v0WSF+hRETJpL+aC9aTtPuuKLasB1LixbV8jL+mzIukm5vPvl+?= =?us-ascii?Q?WuOzkE8gGUAX91Al6IvlQww+DTxo5lV6+HZFlRqKvPWaX9flf2AodjB82HVl?= =?us-ascii?Q?lgvjetzuZa0vmFDKLqJsGqyY+xVgoMpMvEFdGHrkxrdhfqeVHmIi9TokQeuV?= =?us-ascii?Q?Pk0qhPaeOm2VfAjoWiCKIbLjl9KJCug31DKAuz1BDKaDUs9WrmcAW9Y/1VDT?= =?us-ascii?Q?sL7AlBYjcMvWXIwJcaYf9pqOI9mAzqn7agu3Xtvh5++MKWF3SCY9Lgi9cO6U?= =?us-ascii?Q?DY3rlmgizHdj48h+sujpMkW96xxdM89mt1towS+K64IcJL1fkOflHdWXw06r?= =?us-ascii?Q?zgLTumkD7v3Ylr1NSVLd/V6BSUZ1kTBeHuf0BVqTn5tZQAfDE5fi/pSAH5j7?= =?us-ascii?Q?/ytI8N/LWDfvsjq0KL3ch7qLbPlnuIX6BdGpU2sxH51A32DCVW1HqlpMmchm?= =?us-ascii?Q?qPdfBFrc9d12OZiTaCgaFZ0JNUfI1qoLyqTLA1N1EkMABaVmF980Fp7T1Woa?= =?us-ascii?Q?KeexYT5gYqC2NZ4Pq4g8tr5iCKe4BV4bbULkMrukqc7/VY5EOLFGVV8s//sU?= =?us-ascii?Q?q3IHimGgeIw=3D?= X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:PH3PPF9E162731D.namprd11.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230040)(376014)(1800799024)(366016)(7053199007);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?dqReupXdqM+y0ljb+JwMBo8PJLcOruxfVETxvnI32wiClUGQDTbjeN+2BAgs?= =?us-ascii?Q?FjmnqROir66W7Z8VkyoKT1FCwpEc/dqzJx9oRTpHnVa6Q6XAADWlWW+WTnVU?= =?us-ascii?Q?+zL0HcgJWv9wTCuQNmBS/aGQHguwK8+gtAC+SBUMKh2yAiEsIwWqhqwQdtnr?= =?us-ascii?Q?ouEspVxEhXWEuhokmpAMIlnTyFcCLT7eE5IR5XV5yPoiPDjFTrvsUnVODzfV?= =?us-ascii?Q?zp84BQktPfkbi8n+SVpbkmw+WuEKWBQkUE5L22wTTGVgc10bO5Ef/GmrILI1?= =?us-ascii?Q?kOOM4Mz+17Oqi+8dMGotvT8gWReaMmfY1Y2eABweQAVINfsH0XSr8lPQnjKb?= =?us-ascii?Q?BpDkDQNVmfOqE0R7AvoCjtZWrCHIeCUFpxXpT4BbobnIzjR3AKTQ3mLs10+3?= =?us-ascii?Q?JHNR8rjBOL53mWQB7juI0MiRhb/mek5a4y7/sV6s7vRn/XAwqpq+s0tsS2sN?= =?us-ascii?Q?y0b+yT6KgEgVCLixhuddDM6X3XsFyB1CrubR6SX0qchAAKOWmuf8kYaa6P3P?= =?us-ascii?Q?m5rtJlHs9a1m/oKYukfZByxDUXj7yp4DZOkq5RWWj9g54dyEt4DZL5eHxr70?= =?us-ascii?Q?+fpngvj21SoHnAwsEVwmV6gC3qTXbTR+3SNtf/A7vMFKNv5Fxb+CSsNDvsXj?= =?us-ascii?Q?KFTC6QdeqBaKmsoAWb6g6xL7mvir0hO3+L8xoBSSwEv916MvLrOSG4xGnHZo?= =?us-ascii?Q?SQWVPlNEkTNZVJ5Bnixj33JzG9ZDLansMLnDxGsJQ0aCd234Gk+bnpj0cUs5?= =?us-ascii?Q?pBK0m5fvWTw9H2VZU8iWc5OK2pNJvQmcGHGphM5EQCCfQtj+PIR+VaJnQv7h?= =?us-ascii?Q?glCeUioPSCDsTBtYLqj0icVJDL8Ak2UvgV1AqswkFahFvwNnf9G2n796l4n9?= =?us-ascii?Q?3mqYS52GEp0i9QGURxsoq+Q14B0AcGy6yMqVPMw7xfJ0Q1Q9vMY7XxFBQmvt?= =?us-ascii?Q?D6yvSzNE34Co3r9K1xSiZw1TwLewno1DsdO+nMm2Bjq2lSPTsyhW91xW3JcG?= =?us-ascii?Q?G47TfbNxGHXKCFInItHWk/saqH8xfSYZEPm0uyWQ43CwyLHFX61b/SxtxQVb?= =?us-ascii?Q?k6iyhbJi+sBO1rvTLFzmfWtou1wV0XgRt9JoQdkvmMjESc+Fw9YsjL1O1yhs?= =?us-ascii?Q?sjdJc+mLBeOseazKzvPC0DosbYHf9hd0/yY/Gfb4Q9S5ISaAryFZwzKhCgS2?= =?us-ascii?Q?VxWwBWP1wyEBuieveoY5mxpEXTS077QfCtbj6p0QzaST5gTBfN5aYuwZRjCv?= =?us-ascii?Q?Guafc2by854iVwuR85RpZ7ZSpMDwEjqHVVbUnV6NnKxLRTFG6KhZCYVq2sRY?= =?us-ascii?Q?iSim+H/h3Q1sZyYUJzx262hzvpwoMWvPp1E+0IHX6ZWPF6QEnNfow0+2onB3?= =?us-ascii?Q?OsDT+/DEuKXyL0Nt33XVXRy+qG4JNJ2Is4lsN23PWq0xlBD9DJTlUqq5Qua5?= =?us-ascii?Q?EB6TpiWqcTb6noh5plSzuFlvwDLrFQ61VDGJroikd6WYt+OTckdJMFMczTv2?= =?us-ascii?Q?NNYjNmyFguPRS92DQTDnWWlUfR0vOLbqebLOQh+/z4bMsLvKYMQPdAlYS9dD?= =?us-ascii?Q?5dyXMm8JCoYzCMZL8gGlAfrV/qbg9aqsgnHp8IJTAU2GAYvpmVDIbdEGmWOi?= =?us-ascii?Q?bw=3D=3D?= X-MS-Exchange-CrossTenant-Network-Message-Id: f9063487-1937-4072-773e-08dde69562c0 X-MS-Exchange-CrossTenant-AuthSource: PH3PPF9E162731D.namprd11.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 29 Aug 2025 00:45:43.9360 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 46c98d88-e344-4ed4-8496-4ed7712e255d X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: xdx6QIxPHWcJxQKmysUXQjnzeJkkFg/YXVY0D6vZgXrypijW2F2TravK5NfFDreiQ1QMXefDAjFNge0gI6QRaQ== X-MS-Exchange-Transport-CrossTenantHeadersStamped: PH0PR11MB5175 X-OriginatorOrg: intel.com + Michal Mike Rapoport wrote: > From: "Mike Rapoport (Microsoft)" > > There are use cases, for example virtual machine hosts, that create > "persistent" memory regions using memmap= option on x86 or dummy > pmem-region device tree nodes on DT based systems. > > Both these options are inflexible because they create static regions and > the layout of the "persistent" memory cannot be adjusted without reboot > and sometimes they even require firmware update. > > Add a ramdax driver that allows creation of DIMM devices on top of > E820_TYPE_PRAM regions and devicetree pmem-region nodes. While I recognize this driver and the e820 driver are mutually exclusive[1][2]. I do wonder if the use cases are the same? >From a high level I don't like the idea of adding kernel parameters. So if this could solve Michal's problem I'm inclined to go this direction. Ira [1] https://lore.kernel.org/all/aExQ7nSejklEeVn0@kernel.org/ [2] https://lore.kernel.org/all/20250612114210.2786075-1-mclapinski@google.com/ > > The DIMMs support label space management on the "device" and provide a > flexible way to access RAM using fsdax and devdax. > > Signed-off-by: Mike Rapoport (Mircosoft) > --- > drivers/nvdimm/ramdax.c | 281 ++++++++++++++++++++++++++++++++++++++++ > 1 file changed, 281 insertions(+) > create mode 100644 drivers/nvdimm/ramdax.c > > diff --git a/drivers/nvdimm/ramdax.c b/drivers/nvdimm/ramdax.c > new file mode 100644 > index 000000000000..27c5102f600c > --- /dev/null > +++ b/drivers/nvdimm/ramdax.c > @@ -0,0 +1,281 @@ > +// SPDX-License-Identifier: GPL-2.0-only > +/* > + * Copyright (c) 2015, Mike Rapoport, Microsoft > + * > + * Based on e820 pmem driver: > + * Copyright (c) 2015, Christoph Hellwig. > + * Copyright (c) 2015, Intel Corporation. > + */ > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > + > +#include > + > +#define LABEL_AREA_SIZE SZ_128K > + > +struct ramdax_dimm { > + struct nvdimm *nvdimm; > + void *label_area; > +}; > + > +static void ramdax_remove(struct platform_device *pdev) > +{ > + struct nvdimm_bus *nvdimm_bus = platform_get_drvdata(pdev); > + > + /* FIXME: cleanup dimm and region devices */ > + > + nvdimm_bus_unregister(nvdimm_bus); > +} > + > +static int ramdax_register_region(struct resource *res, > + struct nvdimm *nvdimm, > + struct nvdimm_bus *nvdimm_bus) > +{ > + struct nd_mapping_desc mapping; > + struct nd_region_desc ndr_desc; > + struct nd_interleave_set *nd_set; > + int nid = phys_to_target_node(res->start); > + > + nd_set = kzalloc(sizeof(*nd_set), GFP_KERNEL); > + if (!nd_set) > + return -ENOMEM; > + > + nd_set->cookie1 = 0xcafebeefcafebeef; > + nd_set->cookie2 = nd_set->cookie1; > + nd_set->altcookie = nd_set->cookie1; > + > + memset(&mapping, 0, sizeof(mapping)); > + mapping.nvdimm = nvdimm; > + mapping.start = 0; > + mapping.size = resource_size(res) - LABEL_AREA_SIZE; > + > + memset(&ndr_desc, 0, sizeof(ndr_desc)); > + ndr_desc.res = res; > + ndr_desc.numa_node = numa_map_to_online_node(nid); > + ndr_desc.target_node = nid; > + ndr_desc.num_mappings = 1; > + ndr_desc.mapping = &mapping; > + ndr_desc.nd_set = nd_set; > + > + if (!nvdimm_pmem_region_create(nvdimm_bus, &ndr_desc)) > + goto err_free_nd_set; > + > + return 0; > + > +err_free_nd_set: > + kfree(nd_set); > + return -ENXIO; > +} > + > +static int ramdax_register_dimm(struct resource *res, void *data) > +{ > + resource_size_t start = res->start; > + resource_size_t size = resource_size(res); > + unsigned long flags = 0, cmd_mask = 0; > + struct nvdimm_bus *nvdimm_bus = data; > + struct ramdax_dimm *dimm; > + int err; > + > + dimm = kzalloc(sizeof(*dimm), GFP_KERNEL); > + if (!dimm) > + return -ENOMEM; > + > + dimm->label_area = memremap(start + size - LABEL_AREA_SIZE, > + LABEL_AREA_SIZE, MEMREMAP_WB); > + if (!dimm->label_area) > + goto err_free_dimm; > + > + set_bit(NDD_LABELING, &flags); > + set_bit(NDD_REGISTER_SYNC, &flags); > + set_bit(ND_CMD_GET_CONFIG_SIZE, &cmd_mask); > + set_bit(ND_CMD_GET_CONFIG_DATA, &cmd_mask); > + set_bit(ND_CMD_SET_CONFIG_DATA, &cmd_mask); > + dimm->nvdimm = nvdimm_create(nvdimm_bus, dimm, > + /* dimm_attribute_groups */ NULL, > + flags, cmd_mask, 0, NULL); > + if (!dimm->nvdimm) { > + err = -ENOMEM; > + goto err_unmap_label; > + } > + > + err = ramdax_register_region(res, dimm->nvdimm, nvdimm_bus); > + if (err) > + goto err_remove_nvdimm; > + > + return 0; > + > +err_remove_nvdimm: > + nvdimm_delete(dimm->nvdimm); > +err_unmap_label: > + memunmap(dimm->label_area); > +err_free_dimm: > + kfree(dimm); > + return err; > +} > + > +static int ramdax_get_config_size(struct nvdimm *nvdimm, int buf_len, > + struct nd_cmd_get_config_size *cmd) > +{ > + if (sizeof(*cmd) > buf_len) > + return -EINVAL; > + > + *cmd = (struct nd_cmd_get_config_size){ > + .status = 0, > + .config_size = LABEL_AREA_SIZE, > + .max_xfer = 8, > + }; > + > + return 0; > +} > + > +static int ramdax_get_config_data(struct nvdimm *nvdimm, int buf_len, > + struct nd_cmd_get_config_data_hdr *cmd) > +{ > + struct ramdax_dimm *dimm = nvdimm_provider_data(nvdimm); > + > + if (sizeof(*cmd) > buf_len) > + return -EINVAL; > + if (struct_size(cmd, out_buf, cmd->in_length) > buf_len) > + return -EINVAL; > + if (cmd->in_offset + cmd->in_length > LABEL_AREA_SIZE) > + return -EINVAL; > + > + memcpy(cmd->out_buf, dimm->label_area + cmd->in_offset, cmd->in_length); > + > + return 0; > +} > + > +static int ramdax_set_config_data(struct nvdimm *nvdimm, int buf_len, > + struct nd_cmd_set_config_hdr *cmd) > +{ > + struct ramdax_dimm *dimm = nvdimm_provider_data(nvdimm); > + > + if (sizeof(*cmd) > buf_len) > + return -EINVAL; > + if (struct_size(cmd, in_buf, cmd->in_length) > buf_len) > + return -EINVAL; > + if (cmd->in_offset + cmd->in_length > LABEL_AREA_SIZE) > + return -EINVAL; > + > + memcpy(dimm->label_area + cmd->in_offset, cmd->in_buf, cmd->in_length); > + > + return 0; > +} > + > +static int ramdax_nvdimm_ctl(struct nvdimm *nvdimm, unsigned int cmd, > + void *buf, unsigned int buf_len) > +{ > + unsigned long cmd_mask = nvdimm_cmd_mask(nvdimm); > + > + if (!test_bit(cmd, &cmd_mask)) > + return -ENOTTY; > + > + switch (cmd) { > + case ND_CMD_GET_CONFIG_SIZE: > + return ramdax_get_config_size(nvdimm, buf_len, buf); > + case ND_CMD_GET_CONFIG_DATA: > + return ramdax_get_config_data(nvdimm, buf_len, buf); > + case ND_CMD_SET_CONFIG_DATA: > + return ramdax_set_config_data(nvdimm, buf_len, buf); > + default: > + return -ENOTTY; > + } > +} > + > +static int ramdax_ctl(struct nvdimm_bus_descriptor *nd_desc, > + struct nvdimm *nvdimm, unsigned int cmd, void *buf, > + unsigned int buf_len, int *cmd_rc) > +{ > + /* > + * No firmware response to translate, let the transport error > + * code take precedence. > + */ > + *cmd_rc = 0; > + > + if (!nvdimm) > + return -ENOTTY; > + return ramdax_nvdimm_ctl(nvdimm, cmd, buf, buf_len); > +} > + > +static int ramdax_probe_of(struct platform_device *pdev, > + struct nvdimm_bus *bus, struct device_node *np) > +{ > + int err; > + > + for (int i = 0; i < pdev->num_resources; i++) { > + err = ramdax_register_dimm(&pdev->resource[i], bus); > + if (err) > + goto err_unregister; > + } > + > + return 0; > + > +err_unregister: > + /* > + * FIXME: should we unregister the dimms that were registered > + * successfully > + */ > + return err; > +} > + > +static int ramdax_probe(struct platform_device *pdev) > +{ > + static struct nvdimm_bus_descriptor nd_desc; > + struct device *dev = &pdev->dev; > + struct nvdimm_bus *nvdimm_bus; > + struct device_node *np; > + int rc = -ENXIO; > + > + nd_desc.provider_name = "ramdax"; > + nd_desc.module = THIS_MODULE; > + nd_desc.ndctl = ramdax_ctl; > + nvdimm_bus = nvdimm_bus_register(dev, &nd_desc); > + if (!nvdimm_bus) > + goto err; > + > + np = dev_of_node(&pdev->dev); > + if (np) > + rc = ramdax_probe_of(pdev, nvdimm_bus, np); > + else > + rc = walk_iomem_res_desc(IORES_DESC_PERSISTENT_MEMORY_LEGACY, > + IORESOURCE_MEM, 0, -1, nvdimm_bus, > + ramdax_register_dimm); > + if (rc) > + goto err; > + > + platform_set_drvdata(pdev, nvdimm_bus); > + > + return 0; > +err: > + nvdimm_bus_unregister(nvdimm_bus); > + return rc; > +} > + > +#ifdef CONFIG_OF > +static const struct of_device_id ramdax_of_matches[] = { > + { .compatible = "pmem-region", }, > + { }, > +}; > +MODULE_DEVICE_TABLE(of, ramdax_of_matches); > +#endif > + > +static struct platform_driver ramdax_driver = { > + .probe = ramdax_probe, > + .remove = ramdax_remove, > + .driver = { > + .name = "e820_pmem", > + .of_match_table = of_match_ptr(ramdax_of_matches), > + }, > +}; > + > +module_platform_driver(ramdax_driver); > + > +MODULE_DESCRIPTION("NVDIMM support for e820 type-12 memory and OF pmem-region"); > +MODULE_LICENSE("GPL"); > +MODULE_AUTHOR("Microsoft Corporation"); > -- > 2.50.1 >