From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 11224C25B5F for ; Mon, 13 May 2024 04:44:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:CC:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=3BnXs9J7NyUG1REcE9dSUVSbv9D872YxwabA45pGUF0=; b=OxOm/jJqHGFZwi wYFwjfyFB7i6kLGmREfWPyhHwKJ4ARQm2JsVGl2/h2sG2uwyDEBwlTrKNsZpSvyzPIbmuIwTHisLX Wqe+mqLqofP9L4JX68QFrB58z7pjoBeV3yZquZQq/bFOZzQPRHMHH4tn6f5POYe5nG5qVXxsfabW8 XJ8BmyXebQ+XctUakB8in6CqMsOMT55WRmvkk3XUz9hnJVEtXHIVAxS3heImT7Nfeitq7EkdN7gMs U1+UsdtSujTeZW8LSm+jsuC6Jr5auN2NKoDLOfzy3zhI252mAoPmLS6LDX4lH0loRHoaeyQUraWDA YkBDupY+lzDNc4oqXYlw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1s6NXs-0000000BfBE-05Bk; Mon, 13 May 2024 04:44:16 +0000 Received: from mail-mw2nam10on20601.outbound.protection.outlook.com ([2a01:111:f403:2412::601] helo=NAM10-MW2-obe.outbound.protection.outlook.com) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1s6NXo-0000000BfAT-3cMx for linux-arm-kernel@lists.infradead.org; Mon, 13 May 2024 04:44:14 +0000 ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=JLwmU2Gj655tHGWOxk4AuGF5wMb0Nd12xNrmbElRrnHUpPO/TDOLtTov+/ufUyORNQWmr9yhMqxYLe2Qbd1olFTh6FS7zQU47OsKPZFQAp3SvHHElIF6+LmC4mkMbdJhR4ljdzdBu/NJjFWY7TQyl0QCQzvmTbG0Rc9yB7waZNSPBnt3iLX7PBz4VIGIaLLQ/cTADIyaSxXDxArD9LoNOfCVYjhGQwyxYxVCzrTsvjKjIBWzzMcacVTkN3zAReT+lmfaNenuLK9BDgWn4Dvl6V9pxFpDt+kNQWfgJ87ExGnnj4lr9aJOJaWf4Hb0ugENq0ue2CI2cmEuorCBu4sinA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector9901; 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=hZVpGCVOQscqtZoDF4QVIBZt6BKJ9Fmo0aKcmpeYdFE=; b=dfCzY0zMXJnNvGmhnEH6QCqq079l7EuTE9ZpPXiYH+dwm9dlDBFI83jsB+E7OpuRMH9tWV4vS4oyb/Kuh6y5a1whTtMHLAEGAeb5y9AObXYSjXG4QPWPq6nYrbiJD2uvv0m6TUKUY22U7dWNAEm+/x3jriy6oFh84mPof0CD3dZr0TOMTru4nCzXW4rlP1JIYWtdy86dJk/g+Aek7VcdKNtSGrV2eP/5fKqAICLs5uZDbRQwzobC7eKJnvyaVsz4ITeBJkFLBzYzJWVFYh2FWw3Ymxoa6qyX2IVHX22F0aHPTjpAwCMrdJ4gs+MX5NU44Ma6TpR6v/oOrWZIFDJOXQ== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass (sender ip is 216.228.117.160) smtp.rcpttodomain=amd.com smtp.mailfrom=nvidia.com; dmarc=pass (p=reject sp=reject pct=100) action=none header.from=nvidia.com; dkim=none (message not signed); arc=none (0) 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=hZVpGCVOQscqtZoDF4QVIBZt6BKJ9Fmo0aKcmpeYdFE=; b=DkhwcucjXtbN7P+FB3ck8/APq60O6hnqzEuPcGvETt3zaxNidYC/U2OLOoHVgM/7lE7xCDnvz3+NBqtixEBAbq+onLHvPBhDUF27f2CejNbgYhXVqhH2SsTnITMPdr9ryLsT768aO6x5G88IlFfTmZQy6RUECvoNwOCUXIkeQz1rNT7wo2dAHA1/iIfmxy/0B2uRcTA0X2yjIrVaIzlFhyM/g2O9VfMM6xb7mPkhzPTNgGKQCvZd7eqDPzUhoRjYUH32AskoP63jc8ETuLJSykSmcQS6Iiz1JQivwD3h9FIYrFgk0hN/5j2WC2wwWy6XUTUs++FYnI7/L2gzlvmw+Q== Received: from BY3PR05CA0030.namprd05.prod.outlook.com (2603:10b6:a03:254::35) by DS7PR12MB8290.namprd12.prod.outlook.com (2603:10b6:8:d8::15) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.7544.55; Mon, 13 May 2024 04:44:05 +0000 Received: from CO1PEPF000044F3.namprd05.prod.outlook.com (2603:10b6:a03:254:cafe::24) by BY3PR05CA0030.outlook.office365.com (2603:10b6:a03:254::35) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.7587.22 via Frontend Transport; Mon, 13 May 2024 04:44:05 +0000 X-MS-Exchange-Authentication-Results: spf=pass (sender IP is 216.228.117.160) smtp.mailfrom=nvidia.com; dkim=none (message not signed) header.d=none;dmarc=pass action=none header.from=nvidia.com; Received-SPF: Pass (protection.outlook.com: domain of nvidia.com designates 216.228.117.160 as permitted sender) receiver=protection.outlook.com; client-ip=216.228.117.160; helo=mail.nvidia.com; pr=C Received: from mail.nvidia.com (216.228.117.160) by CO1PEPF000044F3.mail.protection.outlook.com (10.167.241.73) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.7587.21 via Frontend Transport; Mon, 13 May 2024 04:44:04 +0000 Received: from rnnvmail201.nvidia.com (10.129.68.8) by mail.nvidia.com (10.129.200.66) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1544.4; Sun, 12 May 2024 21:43:49 -0700 Received: from rnnvmail202.nvidia.com (10.129.68.7) by rnnvmail201.nvidia.com (10.129.68.8) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1544.4; Sun, 12 May 2024 21:43:49 -0700 Received: from nvidia.com (10.127.8.14) by mail.nvidia.com (10.129.68.7) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1544.4 via Frontend Transport; Sun, 12 May 2024 21:43:45 -0700 Date: Sun, 12 May 2024 21:43:42 -0700 From: Nicolin Chen To: Jason Gunthorpe CC: , , , , , , , , , , , , , , , Subject: Re: [PATCH RFCv1 13/14] iommufd: Add mmap infrastructure Message-ID: References: <6fef9ff9944381d51dd18f83ec03785a26754dcf.1712978213.git.nicolinc@nvidia.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: X-NV-OnPremToCloud: ExternallySecured X-EOPAttributedMessage: 0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: CO1PEPF000044F3:EE_|DS7PR12MB8290:EE_ X-MS-Office365-Filtering-Correlation-Id: c4aeb330-ebae-4741-861e-08dc73075190 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230031|82310400017|1800799015|7416005|36860700004|376005; X-Microsoft-Antispam-Message-Info: =?us-ascii?Q?fuOdM6dktizx1i5TkTv7EUoN/RLQoKVpowEiZFIWNp9mJT73q+F8EqKEucY5?= =?us-ascii?Q?0Jp9pkZtjCUpM72npCsMZO7QtLAPNaxocHYmRp5WUXn/jOOF0TX9rGdNdH+i?= =?us-ascii?Q?zbLcNOeKMe7z0wzObVp3IYk/3s0woGC7T3wEKvpbw5+cKHoICXyLe1gOxAwS?= =?us-ascii?Q?SOIzKQdJcOyHc10p/J8Z/68pobTlD5750MsNveKBvQ3D0IVcnQSn3OfxICuS?= =?us-ascii?Q?bGoZzqDVUgwQylJK3ndDDOaFYnWUQKWH3RRU0BoKv1XvCP0towlw2mDUsy/7?= =?us-ascii?Q?hBDkSwHr/6hOvu1cZYcEzb5pyNQEzcDxWHoQ6Gcb12VUE5lDBtXBaONY9a2a?= =?us-ascii?Q?kQOS/c2pyUXXTVWk4LOyPnm2in5hm2qRZE3/mhMGarQewryaV3Bttcsu0GGB?= =?us-ascii?Q?Xdap0Ds0d2Z5WHA0/xm1V9g+FmqWKwAnx3NBcUAEgjWM/r+Xhg37ZNJHWQ8D?= =?us-ascii?Q?zts1sEl+bak2E9os+lp2csmqWgUf1Ln1bCED9ksWgeDihZPoaEP7YMHGl5RV?= =?us-ascii?Q?aLSJEtG7Zn92708D+GyDKlXFBlEvPkQKQxsA/r5o94JQ1R7/2Oq7tKQRjPZi?= =?us-ascii?Q?0DjsvprOdRF4KT3yj9q03C+YIO/s0r56Gg9wOnrUSnCQbNmM4Pm8f65mm/yu?= =?us-ascii?Q?825DyjZynEr/SjBkDzu5fX0SDnAQLEv9rvFB5s38fxPfzf19Ahy758XYOKsN?= =?us-ascii?Q?On5UHes9vfEmffdLRuoa4Hb6U3MUAYXW+dJ4h30FJXQs7OztetK4yR1WtywC?= =?us-ascii?Q?jVwwx2QzLukSYGZSJ+SRGDRzAZ0lBeHh66wgE5tO3WOa9ALyldiqAzHrwJMs?= =?us-ascii?Q?2qIHJwiuPokKVOUTbbNXHo42HTZd8DPxSaLLO4w5S6Z2iQk4leLwP35MtfIY?= =?us-ascii?Q?lDT536VrnsBZGjVVvpb5fv3v4xMt4KPHrFZedNtMyU7Cvm9j5NaSOsKeT3oz?= =?us-ascii?Q?HD1VkW+2Ug1WCnsD/4rJXB8PxTrPPbommwfMc7At7Pb3Yn9wQGezgD3R5hpP?= =?us-ascii?Q?RL+EbQvkckMaKweCZczSbHGQW0BHjGZShHicAWcLDzZL2kCYTuYZ5c04EFqD?= =?us-ascii?Q?l+NiHcKJAp+/FUw8VG5+BruGWETpldEY7iRA8h2mN2wGfNKrQqcfHHpo4IM1?= =?us-ascii?Q?bINZpkbDTu3ZVdBI5crSHpv/DAqlx+zYoHnHD3iTsKXHXiVKAxN13TMeY8qC?= =?us-ascii?Q?mt/xFdP0kgMXi8DAX+IZhihaWLOxRNa1UpdVkqG3NLhsMX0Nkp0ppdrYsm9q?= =?us-ascii?Q?SZyiDemcCavDvQwH7ALYjfQD+VO52x4SvfRssQJj9KInkDgJsQtwi+F+A3L8?= =?us-ascii?Q?5fIwt1Q2kKDtbYvttZpuTiA8YTwk1P1QlTgiHE0KID6ujEhnb3cJL17BYTDj?= =?us-ascii?Q?yING/vaPnctJuTOfAVmYUS72w50V?= X-Forefront-Antispam-Report: CIP:216.228.117.160;CTRY:US;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:mail.nvidia.com;PTR:dc6edge1.nvidia.com;CAT:NONE;SFS:(13230031)(82310400017)(1800799015)(7416005)(36860700004)(376005);DIR:OUT;SFP:1101; X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 13 May 2024 04:44:04.8752 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: c4aeb330-ebae-4741-861e-08dc73075190 X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=43083d15-7273-40c1-b7db-39efd9ccc17a;Ip=[216.228.117.160];Helo=[mail.nvidia.com] X-MS-Exchange-CrossTenant-AuthSource: CO1PEPF000044F3.namprd05.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: DS7PR12MB8290 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240512_214412_928969_D6B4C73A X-CRM114-Status: GOOD ( 24.75 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Sun, May 12, 2024 at 12:19:12PM -0300, Jason Gunthorpe wrote: > On Fri, Apr 12, 2024 at 08:47:10PM -0700, Nicolin Chen wrote: > > Add for sharing the kernel page with user space. This allows to pass > > through HW resource (VCMDQ MMIO pages for example) to user space VMM > > and guest OS. Use vma->vm_pgoff as the carrier of a viommu_id. > > > > Signed-off-by: Nicolin Chen > > --- > > drivers/iommu/iommufd/main.c | 40 ++++++++++++++++++++++++++++++++++++ > > include/linux/iommufd.h | 4 ++++ > > 2 files changed, 44 insertions(+) > > > > diff --git a/drivers/iommu/iommufd/main.c b/drivers/iommu/iommufd/main.c > > index 96ef81530809..5b401c80cca8 100644 > > --- a/drivers/iommu/iommufd/main.c > > +++ b/drivers/iommu/iommufd/main.c > > @@ -16,6 +16,7 @@ > > #include > > #include > > #include > > +#include > > #include > > > > #include "io_pagetable.h" > > @@ -427,11 +428,50 @@ static long iommufd_fops_ioctl(struct file *filp, unsigned int cmd, > > return ret; > > } > > > > +static int iommufd_fops_mmap(struct file *filp, struct vm_area_struct *vma) > > +{ > > + struct iommufd_ctx *ictx = filp->private_data; > > + size_t size = vma->vm_end - vma->vm_start; > > + u32 viommu_id = (u32)vma->vm_pgoff; > > Don't do mmaps this way, it doesn't scale well for future things. > > The pgoff/length should *always* come from the kernel as some > 'mmap_offset' output. I usually call this the mmap cookie. > > In this case have the mmap cookie for the tegra doorbell return in the > viommu's driver data struct, then userspace just passes the opaque > cookie to mmap to get the correct tegra doorbell. > > The core code has some simple xarray/maple tree to allocate cookies > and dispatch them to the correct mmap callback. Usually I'd say to > provide a mmap callback pointer when allocating the cookie. > > Also look at the RDMA Code around mmap there is a bunch of VMA > validations needed. Ie we must insist on VM_SHARED and check > permissions, etc. Yea, the vm_pgoff as a carrier is a bit of hack, as mentioned in the cover-letter. Let me revisit the whole thing and study from RDMA code also. Thanks Nicolin _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel