From patchwork Wed Apr 24 12:00:12 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Thomas Hellstrom X-Patchwork-Id: 10914643 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 0E2BD1515 for ; Wed, 24 Apr 2019 12:00:39 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id F0D1F28A11 for ; Wed, 24 Apr 2019 12:00:38 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id EED3028A25; Wed, 24 Apr 2019 12:00:38 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.0 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,RCVD_IN_DNSWL_NONE autolearn=unavailable version=3.3.1 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id A4A0C28A11 for ; Wed, 24 Apr 2019 12:00:35 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 15C346B0006; Wed, 24 Apr 2019 08:00:32 -0400 (EDT) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id 106336B0008; Wed, 24 Apr 2019 08:00:32 -0400 (EDT) X-Original-To: int-list-linux-mm@kvack.org X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id E4B9E6B000A; Wed, 24 Apr 2019 08:00:31 -0400 (EDT) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from mail-ot1-f70.google.com (mail-ot1-f70.google.com [209.85.210.70]) by kanga.kvack.org (Postfix) with ESMTP id BBDC16B0006 for ; Wed, 24 Apr 2019 08:00:31 -0400 (EDT) Received: by mail-ot1-f70.google.com with SMTP id q23so10663165otk.10 for ; Wed, 24 Apr 2019 05:00:31 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:dkim-signature:from:to:cc:subject:thread-topic :thread-index:date:message-id:references:in-reply-to:accept-language :content-language:content-id:content-transfer-encoding:mime-version; bh=SoHkp5gsl9DN4Hd13XTXMAdh4moT6hIRFvzZcADO0t8=; b=Y6kWSETcw7DUgqCdDEtBg+AG1JjDH9EJwswsJjrUGlBNij/XlD8XAgUE2MUqgVroSb /65xZWvkrEJIyRwKq3FKOZuu3iUlpUj4aqjgU+nOj1sOoc0vLDCKNMAcuqu25k4/Zmxu 6pjOxzLHmpUta1+CPsjw6XS4FOuNid6mBxSNeCRAzvcKUK2AHBDeClXMMQr//oT/DU7E 0GkWKp0EUoRY9sGQ042wpEgN76AwPYiRwxRPdCPZWom7OfM09i1/Lg3iC2CR3poi3Kfr BOuuwK2Zaa4nWnzJDDu9ZaCSNGjgtulhLPeoT/mJvrkOcwtGdn903OjRslp4njDcweWg /FwA== X-Gm-Message-State: APjAAAU1fhyhzMJqERtpt6vGF0BFDVLG0WlfVrFyUK1iNuRVVIV5/6IO i2E/NA6dStfvrevO1sIKUx7V+sbTJbx+HNOoQ88yKUznhhNUtqbdChdcwKEuoRYnNGioRiz76Px 7Tv5FFLaJ2c3Y8KcRdfc0vbeTHgz29JJ8dLBZST84wmo8SWlJSk+ee9tIo7SHjXOjiA== X-Received: by 2002:aca:da43:: with SMTP id r64mr5135481oig.11.1556107231198; Wed, 24 Apr 2019 05:00:31 -0700 (PDT) X-Google-Smtp-Source: APXvYqyFLP5qbHp6YBHdVhPf/R7ozSceg+oiwPNfQcXYI0m4h+Yj/YZ4rhJQ/TSZT4DkMHF252sY X-Received: by 2002:aca:da43:: with SMTP id r64mr5135428oig.11.1556107230259; Wed, 24 Apr 2019 05:00:30 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1556107230; cv=none; d=google.com; s=arc-20160816; b=g8ZoCkPRHubVKD3QVITqMr3qgT7kFHytyhL+aBlngDnkloSQkJ6nSCI+3jO3G5Fpkq s6MEBlnM6zswmd7NmJXv9A87o5aVEcvxJPOb8FTKxXbFNwyWF2PyN51WuoB7zumDnnck QpvOaesLMHv47leo2SmsP62MTwyWhwwwbj4qHb2XRDaS7CwLwZ0A52mYhvciAVIzaEyg KpXQninaCwfTeWDtDnf6zjzEwELESOeT30ZOq8a7VktsZPdewjBTpJ1wX1QP2c0Qo676 hOEk2xdColSBnT9ARNUyULETT4jeR1jQKr+zcLw0TMAueze8ZJA0bPLONOE4RQQkmHMC 1grA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=mime-version:content-transfer-encoding:content-id:content-language :accept-language:in-reply-to:references:message-id:date:thread-index :thread-topic:subject:cc:to:from:dkim-signature; bh=SoHkp5gsl9DN4Hd13XTXMAdh4moT6hIRFvzZcADO0t8=; b=NPKLdyuFAYE4ESkZk8TYtSK0RWuTxQ6DTzU8oKiDbKPB33G8IXlFjt5jF2CzaHMwjK MwURKoHhfLd6v4624MOJq2hGeWVagNWNVKlB5rhDzPZyeDlrpV7F8A69pZRANSZGC/xJ Mq0D52jHCB5AKeZQllq5xv/tD1wDlmxBAYBCLpMYNlLtfJmJaxLFINvlIwL3/+O1pPKJ VKJ4WPZz/Ip+Rxj80GTi05c6JLn7WqzHTkuVaEVgu9qnDO8ROn2ABHS1+fmXyH9a3bzK VtVgUjF3k0kBzKGiW+pToIIKzFBoKoUtrcK6gGPpGknphsHqSc+ZtC0hJVs9zmkTBsdn tJ3w== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@vmware.com header.s=selector1 header.b=NcpECmww; spf=pass (google.com: domain of thellstrom@vmware.com designates 40.107.81.48 as permitted sender) smtp.mailfrom=thellstrom@vmware.com; dmarc=pass (p=QUARANTINE sp=NONE dis=NONE) header.from=vmware.com Received: from NAM01-BY2-obe.outbound.protection.outlook.com (mail-eopbgr810048.outbound.protection.outlook.com. [40.107.81.48]) by mx.google.com with ESMTPS id k204si416748oib.181.2019.04.24.05.00.30 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Wed, 24 Apr 2019 05:00:30 -0700 (PDT) Received-SPF: pass (google.com: domain of thellstrom@vmware.com designates 40.107.81.48 as permitted sender) client-ip=40.107.81.48; Authentication-Results: mx.google.com; dkim=pass header.i=@vmware.com header.s=selector1 header.b=NcpECmww; spf=pass (google.com: domain of thellstrom@vmware.com designates 40.107.81.48 as permitted sender) smtp.mailfrom=thellstrom@vmware.com; dmarc=pass (p=QUARANTINE sp=NONE dis=NONE) header.from=vmware.com DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=vmware.com; s=selector1; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=SoHkp5gsl9DN4Hd13XTXMAdh4moT6hIRFvzZcADO0t8=; b=NcpECmwwletj95HiTJ9bpikBF3RMuaK9UNscgw/COHFUzfO92YZzZon+MKrJs4QekJQIkagEHzjiskH4GZPBH5BK+UUkAYuV+91/dceaHIUkG36dd/R2YdVNS+TvMbbTyXhbiQzOP5qQqf9xuW/zmJnPTifmdtIrRSw7DGB+CXI= Received: from MN2PR05MB6141.namprd05.prod.outlook.com (20.178.241.217) by MN2PR05MB6272.namprd05.prod.outlook.com (20.178.240.146) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.1835.6; Wed, 24 Apr 2019 12:00:12 +0000 Received: from MN2PR05MB6141.namprd05.prod.outlook.com ([fe80::441b:ef64:e316:b294]) by MN2PR05MB6141.namprd05.prod.outlook.com ([fe80::441b:ef64:e316:b294%5]) with mapi id 15.20.1835.010; Wed, 24 Apr 2019 12:00:12 +0000 From: Thomas Hellstrom To: Linux-graphics-maintainer , "dri-devel@lists.freedesktop.org" CC: Pv-drivers , "linux-kernel@vger.kernel.org" , Thomas Hellstrom , Andrew Morton , Matthew Wilcox , Will Deacon , Peter Zijlstra , Rik van Riel , Minchan Kim , Michal Hocko , Huang Ying , Souptick Joarder , =?utf-8?b?SsOpcsO0bWUgR2xpc3Nl?= , "linux-mm@kvack.org" , Ralph Campbell Subject: [PATCH 1/9] mm: Allow the [page|pfn]_mkwrite callbacks to drop the mmap_sem v2 Thread-Topic: [PATCH 1/9] mm: Allow the [page|pfn]_mkwrite callbacks to drop the mmap_sem v2 Thread-Index: AQHU+pVFpIoNyabDrUq+mablu5W5Jw== Date: Wed, 24 Apr 2019 12:00:12 +0000 Message-ID: <20190424115918.3380-2-thellstrom@vmware.com> References: <20190424115918.3380-1-thellstrom@vmware.com> In-Reply-To: <20190424115918.3380-1-thellstrom@vmware.com> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-clientproxiedby: VI1PR07CA0208.eurprd07.prod.outlook.com (2603:10a6:802:3f::32) To MN2PR05MB6141.namprd05.prod.outlook.com (2603:10b6:208:c7::25) authentication-results: spf=none (sender IP is ) smtp.mailfrom=thellstrom@vmware.com; x-ms-exchange-messagesentrepresentingtype: 1 x-mailer: git-send-email 2.20.1 x-originating-ip: [155.4.205.35] x-ms-publictraffictype: Email x-ms-office365-filtering-correlation-id: 3e7e466c-4a1d-4825-7ce5-08d6c8ac67b4 x-microsoft-antispam: BCL:0;PCL:0;RULEID:(2390118)(7020095)(4652040)(8989299)(4534185)(4627221)(201703031133081)(201702281549075)(8990200)(5600141)(711020)(4605104)(2017052603328)(7193020);SRVR:MN2PR05MB6272; x-ms-traffictypediagnostic: MN2PR05MB6272: x-ld-processed: b39138ca-3cee-4b4a-a4d6-cd83d9dd62f0,ExtAddr x-microsoft-antispam-prvs: x-forefront-prvs: 00179089FD x-forefront-antispam-report: SFV:NSPM;SFS:(10009020)(346002)(376002)(136003)(396003)(366004)(39860400002)(199004)(189003)(64756008)(66476007)(71200400001)(66446008)(86362001)(66556008)(305945005)(7416002)(14444005)(50226002)(478600001)(256004)(8936002)(81156014)(7736002)(81166006)(2906002)(66066001)(66946007)(71190400001)(8676002)(4326008)(25786009)(1076003)(66574012)(73956011)(186003)(26005)(6116002)(6512007)(486006)(6486002)(53936002)(110136005)(102836004)(6506007)(386003)(316002)(99286004)(54906003)(5660300002)(11346002)(2616005)(68736007)(14454004)(36756003)(6436002)(446003)(476003)(76176011)(3846002)(52116002)(97736004)(2501003);DIR:OUT;SFP:1101;SCL:1;SRVR:MN2PR05MB6272;H:MN2PR05MB6141.namprd05.prod.outlook.com;FPR:;SPF:None;LANG:en;PTR:InfoNoRecords;A:1;MX:1; received-spf: None (protection.outlook.com: vmware.com does not designate permitted sender hosts) x-ms-exchange-senderadcheck: 1 x-microsoft-antispam-message-info: P55ZQkkMq+fvDR7dqCGUOJwKa5c9q48YjNeF4zlf41jt3c1ucZgc0uSnPKCnyioyaRLhKeOVoHNuQzqdxubXDb+9LMWDV3NZEw2fKIrd6Bg6uqxRTMIi/wLVhZ/S6STpBl716Qu9K0Vx47WB8on/UZewJUvOWPP0m+38Ua/sDzEsl3GKl478kd56gJwS5r0KAoluiFQ2fKeXsNBmw3QzSuMgjowzoZCuqyn747saO8jgLHBNo7uvWWpYKPJRkYZGUo3CpkMJe3t/MuRFf2t9W/OXlrhIzMBCVNrpcocUyK3zvPfiXCpnpziwt300Q8PgOQrRG7ZJWvXbrC0Bk8J7nsSHMBniIYi7SM2ToDwMlFTr1Q05FGQaBDlaM2zmkH6DDS8ADkpcbtYTQlLXHVL6mJ6kNf91dpuj1LpePYie2Jc= Content-ID: <85C7C1DA7782054E8800582057FBFE3C@namprd05.prod.outlook.com> MIME-Version: 1.0 X-OriginatorOrg: vmware.com X-MS-Exchange-CrossTenant-Network-Message-Id: 3e7e466c-4a1d-4825-7ce5-08d6c8ac67b4 X-MS-Exchange-CrossTenant-originalarrivaltime: 24 Apr 2019 12:00:12.7251 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: b39138ca-3cee-4b4a-a4d6-cd83d9dd62f0 X-MS-Exchange-CrossTenant-mailboxtype: HOSTED X-MS-Exchange-Transport-CrossTenantHeadersStamped: MN2PR05MB6272 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: X-Virus-Scanned: ClamAV using ClamSMTP Driver fault callbacks are allowed to drop the mmap_sem when expecting long hardware waits to avoid blocking other mm users. Allow the mkwrite callbacks to do the same by returning early on VM_FAULT_RETRY. In particular we want to be able to drop the mmap_sem when waiting for a reservation object lock on a GPU buffer object. These locks may be held while waiting for the GPU. Cc: Andrew Morton Cc: Matthew Wilcox Cc: Will Deacon Cc: Peter Zijlstra Cc: Rik van Riel Cc: Minchan Kim Cc: Michal Hocko Cc: Huang Ying Cc: Souptick Joarder Cc: "Jérôme Glisse" Cc: linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Thomas Hellstrom Reviewed-by: Ralph Campbell --- v2: Make the order error codes we check for consistent with the order used in the rest of the file. --- mm/memory.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/mm/memory.c b/mm/memory.c index e11ca9dd823f..9580d894f963 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -2144,7 +2144,7 @@ static vm_fault_t do_page_mkwrite(struct vm_fault *vmf) ret = vmf->vma->vm_ops->page_mkwrite(vmf); /* Restore original flags so that caller is not surprised */ vmf->flags = old_flags; - if (unlikely(ret & (VM_FAULT_ERROR | VM_FAULT_NOPAGE))) + if (unlikely(ret & (VM_FAULT_ERROR | VM_FAULT_NOPAGE | VM_FAULT_RETRY))) return ret; if (unlikely(!(ret & VM_FAULT_LOCKED))) { lock_page(page); @@ -2419,7 +2419,7 @@ static vm_fault_t wp_pfn_shared(struct vm_fault *vmf) pte_unmap_unlock(vmf->pte, vmf->ptl); vmf->flags |= FAULT_FLAG_MKWRITE; ret = vma->vm_ops->pfn_mkwrite(vmf); - if (ret & (VM_FAULT_ERROR | VM_FAULT_NOPAGE)) + if (ret & (VM_FAULT_ERROR | VM_FAULT_NOPAGE | VM_FAULT_RETRY)) return ret; return finish_mkwrite_fault(vmf); } @@ -2440,7 +2440,8 @@ static vm_fault_t wp_page_shared(struct vm_fault *vmf) pte_unmap_unlock(vmf->pte, vmf->ptl); tmp = do_page_mkwrite(vmf); if (unlikely(!tmp || (tmp & - (VM_FAULT_ERROR | VM_FAULT_NOPAGE)))) { + (VM_FAULT_ERROR | VM_FAULT_NOPAGE | + VM_FAULT_RETRY)))) { put_page(vmf->page); return tmp; } @@ -3494,7 +3495,8 @@ static vm_fault_t do_shared_fault(struct vm_fault *vmf) unlock_page(vmf->page); tmp = do_page_mkwrite(vmf); if (unlikely(!tmp || - (tmp & (VM_FAULT_ERROR | VM_FAULT_NOPAGE)))) { + (tmp & (VM_FAULT_ERROR | VM_FAULT_NOPAGE | + VM_FAULT_RETRY)))) { put_page(vmf->page); return tmp; } From patchwork Wed Apr 24 12:00:16 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Thomas Hellstrom X-Patchwork-Id: 10914645 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 82DA31515 for ; Wed, 24 Apr 2019 12:00:40 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 72896283E8 for ; Wed, 24 Apr 2019 12:00:40 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 66C5C28AD2; Wed, 24 Apr 2019 12:00:40 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.0 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,RCVD_IN_DNSWL_NONE autolearn=unavailable version=3.3.1 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 70308283E8 for ; Wed, 24 Apr 2019 12:00:39 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 4B1E76B0007; Wed, 24 Apr 2019 08:00:32 -0400 (EDT) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id 457706B0008; Wed, 24 Apr 2019 08:00:32 -0400 (EDT) X-Original-To: int-list-linux-mm@kvack.org X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 2DD026B000C; Wed, 24 Apr 2019 08:00:32 -0400 (EDT) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from mail-ot1-f69.google.com (mail-ot1-f69.google.com [209.85.210.69]) by kanga.kvack.org (Postfix) with ESMTP id DDB316B0007 for ; Wed, 24 Apr 2019 08:00:31 -0400 (EDT) Received: by mail-ot1-f69.google.com with SMTP id k28so10682316otf.3 for ; Wed, 24 Apr 2019 05:00:31 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:dkim-signature:from:to:cc:subject:thread-topic :thread-index:date:message-id:references:in-reply-to:accept-language :content-language:content-id:content-transfer-encoding:mime-version; bh=QBWt2g/z3v41SOvbwMr7NQcEzmiLjjfyLkhHpnrA4lc=; b=Ht3fI1e0VVZQL3b8EPJqQQUTXnk8e7uyeGhMWHMLFiPZNpiuZR0YTACsJNluV/JDAS OOO93z4qhrCkqHdsKvgs0ZMhUnkSDvifvAwenMhyi6zzHhkj8u+41UGfoCj540UceU8N 9ATEg3P2LBnkwl5SiGWkcnyuYl8eN5+JbjCwYpPurT5Y9u5ZUu1JqbSO6YiyyT4sYlsa 0mXvGgFedqy4R5i2vRvajueURiKxAfc+uCznAp4lv7XJsHN2iH51sOJu4STB+ZJ7EIN5 MV9L4caIhgqTjMBeWlXd9XkHb+lx74leA+crr58y8bqM0oTrKjbIj+MvVOuboXnGJRJI VlSw== X-Gm-Message-State: APjAAAX/BnsNzmXa0HB1aVxqpCDN0vhTxZxhUZ7NetRt9XmgqvQNqBuh x+O2mrGMSS/tAfTJtTzPXV14tqrGM+lJkl7hh5GjAQrsdqIvgcLKCYYf84Lx6R5+CcyC3j1cusT pvD9Xdisr6WWacWjpxXY2PjwM2bnIphN2GR+aFUjC3BIC1aHD+W8RoqBdDdNIAjzI+g== X-Received: by 2002:a05:6830:1017:: with SMTP id a23mr20097902otp.120.1556107231217; Wed, 24 Apr 2019 05:00:31 -0700 (PDT) X-Google-Smtp-Source: APXvYqyf2nir3l3+spXQaupsQX4szAZfTiKjHiRiUSTFxbPauMCuJVrj5JCnyGfdFrc+c5L4JSri X-Received: by 2002:a05:6830:1017:: with SMTP id a23mr20097793otp.120.1556107229875; Wed, 24 Apr 2019 05:00:29 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1556107229; cv=none; d=google.com; s=arc-20160816; b=DMYYORdv+2SRj+ypmdk5XTioB3e4uZXE+BuXFy2yRoUyNdqlSWjGmKnIf+M0WuvZVB ZNvlA6nRIsvF7d1W2bypuZGx9mgI4uKw9QzVljX9xKekmh/VJzx7DPqkVFRoivAj4oxx hKzpO5cmT+ozWZ8L6W396Jvs9dOezIVbQoCdHx4ithhfqWcvHT3GP+u82c/3Mr6Of3eH cdvFoH4SI9IDMfwVruhWDv/BpgSmKWVZx2iQ2m0NfkDEMDyc/P/mkMtt5oboZQPbjGA4 cf1gRh5Z9lExV4jWOeQcIiacv/Iw6pbxg0NZdj11hYZJPKyLQFNt00p8pCSvB3cVHwnV ZzIA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=mime-version:content-transfer-encoding:content-id:content-language :accept-language:in-reply-to:references:message-id:date:thread-index :thread-topic:subject:cc:to:from:dkim-signature; bh=QBWt2g/z3v41SOvbwMr7NQcEzmiLjjfyLkhHpnrA4lc=; b=cMeUj4SaJ2b1LO2odr9kxv2I1gZghVHfHq1XJ9sYTaEZy0GWqbbIHbBZOJbSp+oHkj ptdcdULeU8PSHxkgojhZUIMte+fHKnyJEuYTBkCJiKr8oeu2HgEjyPX3nTyRfbpoc/R6 YQKzavfxR6f69cs3Xc4bqjLtJZfXW2RPUHS1ouaLPEy1zq/0+aqpSM/R3bkb+wuLGOkS OhpLvjVHtcTrl6vSv6xmnAf9NK38IcfVYBG4t7fVCF9KL+YCgAaDkFip3ZoRNTbsbxQU xCf2qpPVphtC7ajQqJBpvdXXZ/OvTuSQ6uMuEGcZ+CJ7ERe7RRW4GbXyQ9Xj9glAe5mr J9iw== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@vmware.com header.s=selector1 header.b=Z62YwseQ; spf=pass (google.com: domain of thellstrom@vmware.com designates 40.107.81.48 as permitted sender) smtp.mailfrom=thellstrom@vmware.com; dmarc=pass (p=QUARANTINE sp=NONE dis=NONE) header.from=vmware.com Received: from NAM01-BY2-obe.outbound.protection.outlook.com (mail-eopbgr810048.outbound.protection.outlook.com. [40.107.81.48]) by mx.google.com with ESMTPS id k204si416748oib.181.2019.04.24.05.00.29 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Wed, 24 Apr 2019 05:00:29 -0700 (PDT) Received-SPF: pass (google.com: domain of thellstrom@vmware.com designates 40.107.81.48 as permitted sender) client-ip=40.107.81.48; Authentication-Results: mx.google.com; dkim=pass header.i=@vmware.com header.s=selector1 header.b=Z62YwseQ; spf=pass (google.com: domain of thellstrom@vmware.com designates 40.107.81.48 as permitted sender) smtp.mailfrom=thellstrom@vmware.com; dmarc=pass (p=QUARANTINE sp=NONE dis=NONE) header.from=vmware.com DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=vmware.com; s=selector1; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=QBWt2g/z3v41SOvbwMr7NQcEzmiLjjfyLkhHpnrA4lc=; b=Z62YwseQ+JoFxRhKoSxPMDgH6yR4QK7QGymDPtKCS1hy10z5x9JUgxQWEc+DpNThjdFiK4EvqG4Jqai+L4ZpLIBOwCgQ9m5FnYnDhM763Au8r7knBTIHAzb5JnjJ92xGHtdwmtHdGgU79uvtSUwlQ5tisSa/vzpVIYCdE898Nyk= Received: from MN2PR05MB6141.namprd05.prod.outlook.com (20.178.241.217) by MN2PR05MB6272.namprd05.prod.outlook.com (20.178.240.146) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.1835.6; Wed, 24 Apr 2019 12:00:16 +0000 Received: from MN2PR05MB6141.namprd05.prod.outlook.com ([fe80::441b:ef64:e316:b294]) by MN2PR05MB6141.namprd05.prod.outlook.com ([fe80::441b:ef64:e316:b294%5]) with mapi id 15.20.1835.010; Wed, 24 Apr 2019 12:00:16 +0000 From: Thomas Hellstrom To: Linux-graphics-maintainer , "dri-devel@lists.freedesktop.org" CC: Pv-drivers , "linux-kernel@vger.kernel.org" , Thomas Hellstrom , Andrew Morton , Matthew Wilcox , Will Deacon , Peter Zijlstra , Rik van Riel , Minchan Kim , Michal Hocko , Huang Ying , Souptick Joarder , =?utf-8?b?SsOpcsO0bWUgR2xpc3Nl?= , "linux-mm@kvack.org" , Ralph Campbell Subject: [PATCH 2/9] mm: Add an apply_to_pfn_range interface v2 Thread-Topic: [PATCH 2/9] mm: Add an apply_to_pfn_range interface v2 Thread-Index: AQHU+pVH9stKyQ68Qki9hYNu3940Jg== Date: Wed, 24 Apr 2019 12:00:16 +0000 Message-ID: <20190424115918.3380-3-thellstrom@vmware.com> References: <20190424115918.3380-1-thellstrom@vmware.com> In-Reply-To: <20190424115918.3380-1-thellstrom@vmware.com> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-clientproxiedby: VI1PR07CA0208.eurprd07.prod.outlook.com (2603:10a6:802:3f::32) To MN2PR05MB6141.namprd05.prod.outlook.com (2603:10b6:208:c7::25) authentication-results: spf=none (sender IP is ) smtp.mailfrom=thellstrom@vmware.com; x-ms-exchange-messagesentrepresentingtype: 1 x-mailer: git-send-email 2.20.1 x-originating-ip: [155.4.205.35] x-ms-publictraffictype: Email x-ms-office365-filtering-correlation-id: d6c59e7d-e563-42ee-2880-08d6c8ac69e0 x-microsoft-antispam: BCL:0;PCL:0;RULEID:(2390118)(7020095)(4652040)(8989299)(4534185)(4627221)(201703031133081)(201702281549075)(8990200)(5600141)(711020)(4605104)(2017052603328)(7193020);SRVR:MN2PR05MB6272; x-ms-traffictypediagnostic: MN2PR05MB6272: x-ld-processed: b39138ca-3cee-4b4a-a4d6-cd83d9dd62f0,ExtAddr x-microsoft-antispam-prvs: x-forefront-prvs: 00179089FD x-forefront-antispam-report: SFV:NSPM;SFS:(10009020)(346002)(376002)(136003)(396003)(366004)(39860400002)(199004)(189003)(64756008)(66476007)(71200400001)(66446008)(86362001)(66556008)(305945005)(7416002)(14444005)(50226002)(478600001)(256004)(8936002)(81156014)(7736002)(81166006)(2906002)(66066001)(66946007)(71190400001)(8676002)(4326008)(25786009)(1076003)(66574012)(73956011)(186003)(26005)(6116002)(6512007)(486006)(6486002)(53936002)(110136005)(102836004)(6506007)(386003)(316002)(99286004)(54906003)(5660300002)(11346002)(2616005)(68736007)(14454004)(36756003)(6436002)(446003)(476003)(76176011)(3846002)(52116002)(97736004)(2501003);DIR:OUT;SFP:1101;SCL:1;SRVR:MN2PR05MB6272;H:MN2PR05MB6141.namprd05.prod.outlook.com;FPR:;SPF:None;LANG:en;PTR:InfoNoRecords;A:1;MX:1; received-spf: None (protection.outlook.com: vmware.com does not designate permitted sender hosts) x-ms-exchange-senderadcheck: 1 x-microsoft-antispam-message-info: ACOQSDls9H2r/5KxlQOPQlNLEWLOz7Z8MqV4BTjDgFdzNYsJW/GSs11RwjMfoAVdT1iuFwat8cqwCzBtUqWI5ZVpw0QxWrgChkgDMPRIDqs6g7IncvIXrmWdG+DQmxfqXoMWfRwDocsE1G5zioWW/RrxAcnQnsQhxUpS9FTcAmndhcRDiEwdXnHHMRoTt0J/nbsyVt5atKGI9tMTg4soDY7dTmqrvOSVJv3I+33Z84JejwQUBUw+6RG/29sy0HNqPoS/fUfUo9HbUaiHMkTCy4qq1a//0EpUnCRGjj6rApVFU2KL21/nPds4sld/0B7D6TnGVjHxEMLPGa6LicIFJDfCk+rSwb28EMCvVkLYL+2zV9Vorxxt25nnMHYHImhKQeaGplPYEQWu3o8009bYkeaboH4ZBRXGksxKYo7LR+8= Content-ID: MIME-Version: 1.0 X-OriginatorOrg: vmware.com X-MS-Exchange-CrossTenant-Network-Message-Id: d6c59e7d-e563-42ee-2880-08d6c8ac69e0 X-MS-Exchange-CrossTenant-originalarrivaltime: 24 Apr 2019 12:00:16.1666 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: b39138ca-3cee-4b4a-a4d6-cd83d9dd62f0 X-MS-Exchange-CrossTenant-mailboxtype: HOSTED X-MS-Exchange-Transport-CrossTenantHeadersStamped: MN2PR05MB6272 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: X-Virus-Scanned: ClamAV using ClamSMTP This is basically apply_to_page_range with added functionality: Allocating missing parts of the page table becomes optional, which means that the function can be guaranteed not to error if allocation is disabled. Also passing of the closure struct and callback function becomes different and more in line with how things are done elsewhere. Finally we keep apply_to_page_range as a wrapper around apply_to_pfn_range The reason for not using the page-walk code is that we want to perform the page-walk on vmas pointing to an address space without requiring the mmap_sem to be held rather than on vmas belonging to a process with the mmap_sem held. Notable changes since RFC: Don't export apply_to_pfn range. Cc: Andrew Morton Cc: Matthew Wilcox Cc: Will Deacon Cc: Peter Zijlstra Cc: Rik van Riel Cc: Minchan Kim Cc: Michal Hocko Cc: Huang Ying Cc: Souptick Joarder Cc: "Jérôme Glisse" Cc: linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Thomas Hellstrom Reviewed-by: Ralph Campbell #v1 --- v2: Clearly warn people from using apply_to_pfn_range and apply_to_page_range unless they know what they are doing. --- include/linux/mm.h | 10 ++++ mm/memory.c | 135 ++++++++++++++++++++++++++++++++++----------- 2 files changed, 113 insertions(+), 32 deletions(-) diff --git a/include/linux/mm.h b/include/linux/mm.h index 80bb6408fe73..b7dd4ddd6efb 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -2632,6 +2632,16 @@ typedef int (*pte_fn_t)(pte_t *pte, pgtable_t token, unsigned long addr, extern int apply_to_page_range(struct mm_struct *mm, unsigned long address, unsigned long size, pte_fn_t fn, void *data); +struct pfn_range_apply; +typedef int (*pter_fn_t)(pte_t *pte, pgtable_t token, unsigned long addr, + struct pfn_range_apply *closure); +struct pfn_range_apply { + struct mm_struct *mm; + pter_fn_t ptefn; + unsigned int alloc; +}; +extern int apply_to_pfn_range(struct pfn_range_apply *closure, + unsigned long address, unsigned long size); #ifdef CONFIG_PAGE_POISONING extern bool page_poisoning_enabled(void); diff --git a/mm/memory.c b/mm/memory.c index 9580d894f963..0a86ee527ffa 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -1938,18 +1938,17 @@ int vm_iomap_memory(struct vm_area_struct *vma, phys_addr_t start, unsigned long } EXPORT_SYMBOL(vm_iomap_memory); -static int apply_to_pte_range(struct mm_struct *mm, pmd_t *pmd, - unsigned long addr, unsigned long end, - pte_fn_t fn, void *data) +static int apply_to_pte_range(struct pfn_range_apply *closure, pmd_t *pmd, + unsigned long addr, unsigned long end) { pte_t *pte; int err; pgtable_t token; spinlock_t *uninitialized_var(ptl); - pte = (mm == &init_mm) ? + pte = (closure->mm == &init_mm) ? pte_alloc_kernel(pmd, addr) : - pte_alloc_map_lock(mm, pmd, addr, &ptl); + pte_alloc_map_lock(closure->mm, pmd, addr, &ptl); if (!pte) return -ENOMEM; @@ -1960,86 +1959,109 @@ static int apply_to_pte_range(struct mm_struct *mm, pmd_t *pmd, token = pmd_pgtable(*pmd); do { - err = fn(pte++, token, addr, data); + err = closure->ptefn(pte++, token, addr, closure); if (err) break; } while (addr += PAGE_SIZE, addr != end); arch_leave_lazy_mmu_mode(); - if (mm != &init_mm) + if (closure->mm != &init_mm) pte_unmap_unlock(pte-1, ptl); return err; } -static int apply_to_pmd_range(struct mm_struct *mm, pud_t *pud, - unsigned long addr, unsigned long end, - pte_fn_t fn, void *data) +static int apply_to_pmd_range(struct pfn_range_apply *closure, pud_t *pud, + unsigned long addr, unsigned long end) { pmd_t *pmd; unsigned long next; - int err; + int err = 0; BUG_ON(pud_huge(*pud)); - pmd = pmd_alloc(mm, pud, addr); + pmd = pmd_alloc(closure->mm, pud, addr); if (!pmd) return -ENOMEM; + do { next = pmd_addr_end(addr, end); - err = apply_to_pte_range(mm, pmd, addr, next, fn, data); + if (!closure->alloc && pmd_none_or_clear_bad(pmd)) + continue; + err = apply_to_pte_range(closure, pmd, addr, next); if (err) break; } while (pmd++, addr = next, addr != end); return err; } -static int apply_to_pud_range(struct mm_struct *mm, p4d_t *p4d, - unsigned long addr, unsigned long end, - pte_fn_t fn, void *data) +static int apply_to_pud_range(struct pfn_range_apply *closure, p4d_t *p4d, + unsigned long addr, unsigned long end) { pud_t *pud; unsigned long next; - int err; + int err = 0; - pud = pud_alloc(mm, p4d, addr); + pud = pud_alloc(closure->mm, p4d, addr); if (!pud) return -ENOMEM; + do { next = pud_addr_end(addr, end); - err = apply_to_pmd_range(mm, pud, addr, next, fn, data); + if (!closure->alloc && pud_none_or_clear_bad(pud)) + continue; + err = apply_to_pmd_range(closure, pud, addr, next); if (err) break; } while (pud++, addr = next, addr != end); return err; } -static int apply_to_p4d_range(struct mm_struct *mm, pgd_t *pgd, - unsigned long addr, unsigned long end, - pte_fn_t fn, void *data) +static int apply_to_p4d_range(struct pfn_range_apply *closure, pgd_t *pgd, + unsigned long addr, unsigned long end) { p4d_t *p4d; unsigned long next; - int err; + int err = 0; - p4d = p4d_alloc(mm, pgd, addr); + p4d = p4d_alloc(closure->mm, pgd, addr); if (!p4d) return -ENOMEM; + do { next = p4d_addr_end(addr, end); - err = apply_to_pud_range(mm, p4d, addr, next, fn, data); + if (!closure->alloc && p4d_none_or_clear_bad(p4d)) + continue; + err = apply_to_pud_range(closure, p4d, addr, next); if (err) break; } while (p4d++, addr = next, addr != end); return err; } -/* - * Scan a region of virtual memory, filling in page tables as necessary - * and calling a provided function on each leaf page table. +/** + * apply_to_pfn_range - Scan a region of virtual memory, calling a provided + * function on each leaf page table entry + * @closure: Details about how to scan and what function to apply + * @addr: Start virtual address + * @size: Size of the region + * + * If @closure->alloc is set to 1, the function will fill in the page table + * as necessary. Otherwise it will skip non-present parts. + * Note: The caller must ensure that the range does not contain huge pages. + * The caller must also assure that the proper mmu_notifier functions are + * called before and after the call to apply_to_pfn_range. + * + * WARNING: Do not use this function unless you know exactly what you are + * doing. It is lacking support for huge pages and transparent huge pages. + * + * Return: Zero on success. If the provided function returns a non-zero status, + * the page table walk will terminate and that status will be returned. + * If @closure->alloc is set to 1, then this function may also return memory + * allocation errors arising from allocating page table memory. */ -int apply_to_page_range(struct mm_struct *mm, unsigned long addr, - unsigned long size, pte_fn_t fn, void *data) +int apply_to_pfn_range(struct pfn_range_apply *closure, + unsigned long addr, unsigned long size) { pgd_t *pgd; unsigned long next; @@ -2049,16 +2071,65 @@ int apply_to_page_range(struct mm_struct *mm, unsigned long addr, if (WARN_ON(addr >= end)) return -EINVAL; - pgd = pgd_offset(mm, addr); + pgd = pgd_offset(closure->mm, addr); do { next = pgd_addr_end(addr, end); - err = apply_to_p4d_range(mm, pgd, addr, next, fn, data); + if (!closure->alloc && pgd_none_or_clear_bad(pgd)) + continue; + err = apply_to_p4d_range(closure, pgd, addr, next); if (err) break; } while (pgd++, addr = next, addr != end); return err; } + +/** + * struct page_range_apply - Closure structure for apply_to_page_range() + * @pter: The base closure structure we derive from + * @fn: The leaf pte function to call + * @data: The leaf pte function closure + */ +struct page_range_apply { + struct pfn_range_apply pter; + pte_fn_t fn; + void *data; +}; + +/* + * Callback wrapper to enable use of apply_to_pfn_range for + * the apply_to_page_range interface + */ +static int apply_to_page_range_wrapper(pte_t *pte, pgtable_t token, + unsigned long addr, + struct pfn_range_apply *pter) +{ + struct page_range_apply *pra = + container_of(pter, typeof(*pra), pter); + + return pra->fn(pte, token, addr, pra->data); +} + +/* + * Scan a region of virtual memory, filling in page tables as necessary + * and calling a provided function on each leaf page table. + * + * WARNING: Do not use this function unless you know exactly what you are + * doing. It is lacking support for huge pages and transparent huge pages. + */ +int apply_to_page_range(struct mm_struct *mm, unsigned long addr, + unsigned long size, pte_fn_t fn, void *data) +{ + struct page_range_apply pra = { + .pter = {.mm = mm, + .alloc = 1, + .ptefn = apply_to_page_range_wrapper }, + .fn = fn, + .data = data + }; + + return apply_to_pfn_range(&pra.pter, addr, size); +} EXPORT_SYMBOL_GPL(apply_to_page_range); /* From patchwork Wed Apr 24 12:00:19 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Thomas Hellstrom X-Patchwork-Id: 10914657 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 745621515 for ; Wed, 24 Apr 2019 12:00:52 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 56E2528AD1 for ; Wed, 24 Apr 2019 12:00:52 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 547BE28AD7; Wed, 24 Apr 2019 12:00:52 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.0 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,RCVD_IN_DNSWL_NONE autolearn=unavailable version=3.3.1 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 3032328AC8 for ; Wed, 24 Apr 2019 12:00:44 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id DB2216B0008; Wed, 24 Apr 2019 08:00:37 -0400 (EDT) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id D8C006B000A; Wed, 24 Apr 2019 08:00:37 -0400 (EDT) X-Original-To: int-list-linux-mm@kvack.org X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id B673A6B000C; Wed, 24 Apr 2019 08:00:37 -0400 (EDT) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from mail-oi1-f199.google.com (mail-oi1-f199.google.com [209.85.167.199]) by kanga.kvack.org (Postfix) with ESMTP id 7EDD96B0008 for ; Wed, 24 Apr 2019 08:00:37 -0400 (EDT) Received: by mail-oi1-f199.google.com with SMTP id l12so1853879oic.20 for ; Wed, 24 Apr 2019 05:00:37 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:dkim-signature:from:to:cc:subject:thread-topic :thread-index:date:message-id:references:in-reply-to:accept-language :content-language:content-id:content-transfer-encoding:mime-version; bh=IEr/6V19VpqUzT9Cp1wgcEldD8IODKgeaNXZKr2MDsw=; b=sPesg0/r1vPaxYIPZbZfQdi4oZNRyaV9jGJkIAF9k2tjRmMhbapKRRHaaOL+9Ymtqv IjOq+Bup9196BvWem0GzvD0FyGJYeDxnbKkgsJOsNvcPSQ5uqRWDYttrjKEKzxY5iSMQ Z3NaM8Z/ru/0f65bHHyJPZK8whpBJrCsyAgiRj5PR1YHJIh3nI6q4C3olHXnfIS6r0c2 KaGqaJOo+fIvcO1NTdDR+HhdwMwzIWYYWySyB73t8ZvlvgL6zSsV1WsWDugd8qU+dv4O h/t/EOja5HSe55FnpHL+A7yWhX3kJa/odMGn8c+RyYshjhaAOYSOglUK/aSPX5sT5NOO S9hA== X-Gm-Message-State: APjAAAUMfZMt4m+c84QbBq9Q6C3O+xPG2s9pAyRNvg07K9OK6VgGCutH tYQTQlAtudX9BPCEv1uKPcn7efQzT9VP4hb8GK14AVAelwmn1YZyIdgEtmYSRQuSH+FBRbAdedo s07Oggm15os1UtHHdS47RnmPsW+YZbbcBstN9Mfhz3lpRtqHpshn7MgjEaOPoouyfkQ== X-Received: by 2002:aca:35c5:: with SMTP id c188mr5414139oia.18.1556107237034; Wed, 24 Apr 2019 05:00:37 -0700 (PDT) X-Google-Smtp-Source: APXvYqw1oGUynaWDQ4ZpGp56ufAIXrqYazDXwK8243jcu5mN2XVOBzFp1Mgzi0IitGrMW4aG/0ne X-Received: by 2002:aca:35c5:: with SMTP id c188mr5414068oia.18.1556107235651; Wed, 24 Apr 2019 05:00:35 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1556107235; cv=none; d=google.com; s=arc-20160816; b=WTWKdwa5f5gjY7P2HSNuTPfWtLHOQstAKzk2QUtuKB1Jg4AJHGUdMQwMTekjHbma3v 4Jk6ucJvEvkhxU43wIrhZoYq1nD4n/z6XPLi+g6g07tkAg+vSUBc/Zf0kqFvWzXato3u 1E9aTnvrIQeF6fMj/4KwyH27QBgYIVIuYFVTDJU3Iawvz15PjLzIK4cRhkjhiwCwb5pT ZM4KsbAhZYnYY9dh5SWauMCvUhYqgVA6WQ/bsCVvquPO6cla8shXZYgNC4du+oT1Phzx OUHfLxdfoc5+6FrnixisJ2xn1+tVAndYQVY4m0xOxsgUUe+c7g2rZvP6/h6Hw0Kpm+F6 XXbg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=mime-version:content-transfer-encoding:content-id:content-language :accept-language:in-reply-to:references:message-id:date:thread-index :thread-topic:subject:cc:to:from:dkim-signature; bh=IEr/6V19VpqUzT9Cp1wgcEldD8IODKgeaNXZKr2MDsw=; b=iqiFk0jRNf6wp2GdMkmoGnxWppjYxGCBzE5pZLQyrla+GFodlppVR5EWAu9JaYmOi3 BozS2Nbc5WROeIbUJERQJpTpGWhAcf56/q2zpihjFsw6kJtqZyG8pL4yfJM/uCZTSoSU RSec5YHvHADkpGtu8DGBEWog0ePYgrNWKEfX9Kf25KkuutZZoQR2KEY2igrWZpXjinWk TFq1C2Tpu2mLO3de/VPwsItC+qiz9AvZkEB9a/lxpIB2XO7JzCE63zQMrgONf4tSrtJd Bi3jozYF9xV4cwG7ZpxrO6BpGaHS3MwDQogNVelkJYO2ItdBL+cfDu8yMVw6PC4Bq25c 3mAw== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@vmware.com header.s=selector1 header.b=mkMVGDVR; spf=pass (google.com: domain of thellstrom@vmware.com designates 40.107.71.88 as permitted sender) smtp.mailfrom=thellstrom@vmware.com; dmarc=pass (p=QUARANTINE sp=NONE dis=NONE) header.from=vmware.com Received: from NAM05-BY2-obe.outbound.protection.outlook.com (mail-eopbgr710088.outbound.protection.outlook.com. [40.107.71.88]) by mx.google.com with ESMTPS id g26si10320092otk.123.2019.04.24.05.00.35 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 24 Apr 2019 05:00:35 -0700 (PDT) Received-SPF: pass (google.com: domain of thellstrom@vmware.com designates 40.107.71.88 as permitted sender) client-ip=40.107.71.88; Authentication-Results: mx.google.com; dkim=pass header.i=@vmware.com header.s=selector1 header.b=mkMVGDVR; spf=pass (google.com: domain of thellstrom@vmware.com designates 40.107.71.88 as permitted sender) smtp.mailfrom=thellstrom@vmware.com; dmarc=pass (p=QUARANTINE sp=NONE dis=NONE) header.from=vmware.com DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=vmware.com; s=selector1; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=IEr/6V19VpqUzT9Cp1wgcEldD8IODKgeaNXZKr2MDsw=; b=mkMVGDVRkwK5/0m20vNUolz0KkBWA33amLBsb7NAM9gfcZ8i7MKKVshzErODoIl9KePsOqFXj0B0sHnjcQYw7JQuAUvFi+O/zQIKpmqBhn2bZTjXslldnkWGXEDAp93eZKCVrX0lu3wY5AWA0SG2M3f2olntMSNLJ6OrJGOuawY= Received: from MN2PR05MB6141.namprd05.prod.outlook.com (20.178.241.217) by MN2PR05MB6687.namprd05.prod.outlook.com (20.178.249.75) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.1835.7; Wed, 24 Apr 2019 12:00:19 +0000 Received: from MN2PR05MB6141.namprd05.prod.outlook.com ([fe80::441b:ef64:e316:b294]) by MN2PR05MB6141.namprd05.prod.outlook.com ([fe80::441b:ef64:e316:b294%5]) with mapi id 15.20.1835.010; Wed, 24 Apr 2019 12:00:19 +0000 From: Thomas Hellstrom To: Linux-graphics-maintainer , "dri-devel@lists.freedesktop.org" CC: Pv-drivers , "linux-kernel@vger.kernel.org" , Thomas Hellstrom , Andrew Morton , Matthew Wilcox , Will Deacon , Peter Zijlstra , Rik van Riel , Minchan Kim , Michal Hocko , Huang Ying , Souptick Joarder , =?utf-8?b?SsOpcsO0bWUgR2xpc3Nl?= , "linux-mm@kvack.org" , Ralph Campbell Subject: [PATCH 3/9] mm: Add write-protect and clean utilities for address space ranges v2 Thread-Topic: [PATCH 3/9] mm: Add write-protect and clean utilities for address space ranges v2 Thread-Index: AQHU+pVJVDvhhZ6C/UaopXjxOqfjAA== Date: Wed, 24 Apr 2019 12:00:19 +0000 Message-ID: <20190424115918.3380-4-thellstrom@vmware.com> References: <20190424115918.3380-1-thellstrom@vmware.com> In-Reply-To: <20190424115918.3380-1-thellstrom@vmware.com> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-clientproxiedby: VI1PR07CA0208.eurprd07.prod.outlook.com (2603:10a6:802:3f::32) To MN2PR05MB6141.namprd05.prod.outlook.com (2603:10b6:208:c7::25) authentication-results: spf=none (sender IP is ) smtp.mailfrom=thellstrom@vmware.com; x-ms-exchange-messagesentrepresentingtype: 1 x-mailer: git-send-email 2.20.1 x-originating-ip: [155.4.205.35] x-ms-publictraffictype: Email x-ms-office365-filtering-correlation-id: 0fc9cd56-49e8-4291-d86f-08d6c8ac6bea x-microsoft-antispam: BCL:0;PCL:0;RULEID:(2390118)(7020095)(4652040)(8989299)(4534185)(4627221)(201703031133081)(201702281549075)(8990200)(5600141)(711020)(4605104)(2017052603328)(7193020);SRVR:MN2PR05MB6687; x-ms-traffictypediagnostic: MN2PR05MB6687: x-ld-processed: b39138ca-3cee-4b4a-a4d6-cd83d9dd62f0,ExtAddr x-microsoft-antispam-prvs: x-forefront-prvs: 00179089FD x-forefront-antispam-report: SFV:NSPM;SFS:(10009020)(39860400002)(376002)(136003)(346002)(396003)(366004)(189003)(199004)(8676002)(81156014)(64756008)(66946007)(66556008)(52116002)(6506007)(53936002)(66476007)(68736007)(102836004)(8936002)(6116002)(66446008)(7416002)(30864003)(6512007)(36756003)(186003)(81166006)(26005)(73956011)(7736002)(305945005)(316002)(66066001)(2501003)(66574012)(50226002)(97736004)(3846002)(86362001)(1076003)(110136005)(5660300002)(2616005)(14454004)(11346002)(25786009)(486006)(2906002)(76176011)(71200400001)(71190400001)(99286004)(476003)(386003)(256004)(4326008)(446003)(14444005)(6486002)(6436002)(54906003)(478600001);DIR:OUT;SFP:1101;SCL:1;SRVR:MN2PR05MB6687;H:MN2PR05MB6141.namprd05.prod.outlook.com;FPR:;SPF:None;LANG:en;PTR:InfoNoRecords;MX:1;A:1; received-spf: None (protection.outlook.com: vmware.com does not designate permitted sender hosts) x-ms-exchange-senderadcheck: 1 x-microsoft-antispam-message-info: qHcMliZ9ohQeGmEajnYCtgoKfXcsneelizAm1tgZW73hB5LB5o+VPxkldPqBjSqOSKJzw22ltWLa022DLrO74lP7webasXFL8o2hDFj65XkwVztQZGyc5Pvwf7UXe7xG4+SEQSZKpGDO6g2fi/pbad9a0U7uv3v9wD9C2riLUxLX1zkceAVsTFt+TnzdVPX1TYEFmb6uXvKghzEtf0k/RUb8h0HctYomTivfZBNXYjBwgXKPqAX2Bknm2IczQhR1Hw3BSMqi8b892GTUyf8EqHf42vXtF9XRbhjGs5o3+rV15xYXtavcgOyr6JnHbi7Bu5+ELqO+wGeGYm8ufMnrDhuoUjWpAphxAE0d59WR+Mg4IoFlh1+1nWQTtHYBTsKQHr49zlXU/T6PCQOQkFv/F0sut2riW60dvJ7SZUPVlak= Content-ID: <3A5E02C95498424EB49F87261DA93F4F@namprd05.prod.outlook.com> MIME-Version: 1.0 X-OriginatorOrg: vmware.com X-MS-Exchange-CrossTenant-Network-Message-Id: 0fc9cd56-49e8-4291-d86f-08d6c8ac6bea X-MS-Exchange-CrossTenant-originalarrivaltime: 24 Apr 2019 12:00:19.6531 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: b39138ca-3cee-4b4a-a4d6-cd83d9dd62f0 X-MS-Exchange-CrossTenant-mailboxtype: HOSTED X-MS-Exchange-Transport-CrossTenantHeadersStamped: MN2PR05MB6687 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: X-Virus-Scanned: ClamAV using ClamSMTP Add two utilities to a) write-protect and b) clean all ptes pointing into a range of an address space The utilities are intended to aid in tracking dirty pages (either driver-allocated system memory or pci device memory). The write-protect utility should be used in conjunction with page_mkwrite() and pfn_mkwrite() to trigger write page-faults on page accesses. Typically one would want to use this on sparse accesses into large memory regions. The clean utility should be used to utilize hardware dirtying functionality and avoid the overhead of page-faults, typically on large accesses into small memory regions. The added file "as_dirty_helpers.c" is initially listed as maintained by VMware under our DRM driver. If somebody would like it elsewhere, that's of course no problem. Notable changes since RFC: - Added comments to help avoid the usage of these function for VMAs it's not intended for. We also do advisory checks on the vm_flags and warn on illegal usage. - Perform the pte modifications the same way softdirty does. - Add mmu_notifier range invalidation calls. - Add a config option so that this code is not unconditionally included. - Tell the mmu_gather code about pending tlb flushes. Cc: Andrew Morton Cc: Matthew Wilcox Cc: Will Deacon Cc: Peter Zijlstra Cc: Rik van Riel Cc: Minchan Kim Cc: Michal Hocko Cc: Huang Ying Cc: Souptick Joarder Cc: "Jérôme Glisse" Cc: linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Thomas Hellstrom Reviewed-by: Ralph Campbell #v1 --- v2: Fix formatting and typos. Change file-name of the added file, and don't compile it unless configured to do so. --- MAINTAINERS | 1 + include/linux/mm.h | 9 +- mm/Kconfig | 3 + mm/Makefile | 1 + mm/as_dirty_helpers.c | 297 ++++++++++++++++++++++++++++++++++++++++++ 5 files changed, 310 insertions(+), 1 deletion(-) create mode 100644 mm/as_dirty_helpers.c diff --git a/MAINTAINERS b/MAINTAINERS index 35e6357f9d30..015e1e758bf6 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -4971,6 +4971,7 @@ T: git git://people.freedesktop.org/~thomash/linux S: Supported F: drivers/gpu/drm/vmwgfx/ F: include/uapi/drm/vmwgfx_drm.h +F: mm/as_dirty_helpers.c DRM DRIVERS M: David Airlie diff --git a/include/linux/mm.h b/include/linux/mm.h index b7dd4ddd6efb..62f24dd0bfa0 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -2642,7 +2642,14 @@ struct pfn_range_apply { }; extern int apply_to_pfn_range(struct pfn_range_apply *closure, unsigned long address, unsigned long size); - +unsigned long apply_as_wrprotect(struct address_space *mapping, + pgoff_t first_index, pgoff_t nr); +unsigned long apply_as_clean(struct address_space *mapping, + pgoff_t first_index, pgoff_t nr, + pgoff_t bitmap_pgoff, + unsigned long *bitmap, + pgoff_t *start, + pgoff_t *end); #ifdef CONFIG_PAGE_POISONING extern bool page_poisoning_enabled(void); extern void kernel_poison_pages(struct page *page, int numpages, int enable); diff --git a/mm/Kconfig b/mm/Kconfig index 25c71eb8a7db..80e41cdbb4ae 100644 --- a/mm/Kconfig +++ b/mm/Kconfig @@ -758,4 +758,7 @@ config GUP_BENCHMARK config ARCH_HAS_PTE_SPECIAL bool +config AS_DIRTY_HELPERS + bool + endmenu diff --git a/mm/Makefile b/mm/Makefile index d210cc9d6f80..4bf396ba3a00 100644 --- a/mm/Makefile +++ b/mm/Makefile @@ -99,3 +99,4 @@ obj-$(CONFIG_HARDENED_USERCOPY) += usercopy.o obj-$(CONFIG_PERCPU_STATS) += percpu-stats.o obj-$(CONFIG_HMM) += hmm.o obj-$(CONFIG_MEMFD_CREATE) += memfd.o +obj-$(CONFIG_AS_DIRTY_HELPERS) += as_dirty_helpers.o diff --git a/mm/as_dirty_helpers.c b/mm/as_dirty_helpers.c new file mode 100644 index 000000000000..26984841d18f --- /dev/null +++ b/mm/as_dirty_helpers.c @@ -0,0 +1,297 @@ +// SPDX-License-Identifier: GPL-2.0 +#include +#include +#include +#include +#include +#include +#include + +/** + * struct apply_as - Closure structure for apply_as_range + * @base: struct pfn_range_apply we derive from + * @start: Address of first modified pte + * @end: Address of last modified pte + 1 + * @total: Total number of modified ptes + * @vma: Pointer to the struct vm_area_struct we're currently operating on + */ +struct apply_as { + struct pfn_range_apply base; + unsigned long start; + unsigned long end; + unsigned long total; + const struct vm_area_struct *vma; +}; + +/** + * apply_pt_wrprotect - Leaf pte callback to write-protect a pte + * @pte: Pointer to the pte + * @token: Page table token, see apply_to_pfn_range() + * @addr: The virtual page address + * @closure: Pointer to a struct pfn_range_apply embedded in a + * struct apply_as + * + * The function write-protects a pte and records the range in + * virtual address space of touched ptes for efficient range TLB flushes. + * + * Return: Always zero. + */ +static int apply_pt_wrprotect(pte_t *pte, pgtable_t token, + unsigned long addr, + struct pfn_range_apply *closure) +{ + struct apply_as *aas = container_of(closure, typeof(*aas), base); + pte_t ptent = *pte; + + if (pte_write(ptent)) { + ptent = ptep_modify_prot_start(closure->mm, addr, pte); + ptent = pte_wrprotect(ptent); + ptep_modify_prot_commit(closure->mm, addr, pte, ptent); + aas->total++; + aas->start = min(aas->start, addr); + aas->end = max(aas->end, addr + PAGE_SIZE); + } + + return 0; +} + +/** + * struct apply_as_clean - Closure structure for apply_as_clean + * @base: struct apply_as we derive from + * @bitmap_pgoff: Address_space Page offset of the first bit in @bitmap + * @bitmap: Bitmap with one bit for each page offset in the address_space range + * covered. + * @start: Address_space page offset of first modified pte relative + * to @bitmap_pgoff + * @end: Address_space page offset of last modified pte relative + * to @bitmap_pgoff + */ +struct apply_as_clean { + struct apply_as base; + pgoff_t bitmap_pgoff; + unsigned long *bitmap; + pgoff_t start; + pgoff_t end; +}; + +/** + * apply_pt_clean - Leaf pte callback to clean a pte + * @pte: Pointer to the pte + * @token: Page table token, see apply_to_pfn_range() + * @addr: The virtual page address + * @closure: Pointer to a struct pfn_range_apply embedded in a + * struct apply_as_clean + * + * The function cleans a pte and records the range in + * virtual address space of touched ptes for efficient TLB flushes. + * It also records dirty ptes in a bitmap representing page offsets + * in the address_space, as well as the first and last of the bits + * touched. + * + * Return: Always zero. + */ +static int apply_pt_clean(pte_t *pte, pgtable_t token, + unsigned long addr, + struct pfn_range_apply *closure) +{ + struct apply_as *aas = container_of(closure, typeof(*aas), base); + struct apply_as_clean *clean = container_of(aas, typeof(*clean), base); + pte_t ptent = *pte; + + if (pte_dirty(ptent)) { + pgoff_t pgoff = ((addr - aas->vma->vm_start) >> PAGE_SHIFT) + + aas->vma->vm_pgoff - clean->bitmap_pgoff; + + ptent = ptep_modify_prot_start(closure->mm, addr, pte); + ptent = pte_mkclean(ptent); + ptep_modify_prot_commit(closure->mm, addr, pte, ptent); + + aas->total++; + aas->start = min(aas->start, addr); + aas->end = max(aas->end, addr + PAGE_SIZE); + + __set_bit(pgoff, clean->bitmap); + clean->start = min(clean->start, pgoff); + clean->end = max(clean->end, pgoff + 1); + } + + return 0; +} + +/** + * apply_as_range - Apply a pte callback to all PTEs pointing into a range + * of an address_space. + * @mapping: Pointer to the struct address_space + * @aas: Closure structure + * @first_index: First page offset in the address_space + * @nr: Number of incremental page offsets to cover + * + * Return: Number of ptes touched. Note that this number might be larger + * than @nr if there are overlapping vmas + */ +static unsigned long apply_as_range(struct address_space *mapping, + struct apply_as *aas, + pgoff_t first_index, pgoff_t nr) +{ + struct vm_area_struct *vma; + pgoff_t vba, vea, cba, cea; + unsigned long start_addr, end_addr; + struct mmu_notifier_range range; + + i_mmap_lock_read(mapping); + vma_interval_tree_foreach(vma, &mapping->i_mmap, first_index, + first_index + nr - 1) { + unsigned long vm_flags = READ_ONCE(vma->vm_flags); + + /* + * We can only do advisory flag tests below, since we can't + * require the vm's mmap_sem to be held to protect the flags. + * Therefore, callers that strictly depend on specific mmap + * flags to remain constant throughout the operation must + * either ensure those flags are immutable for all relevant + * vmas or can't use this function. Fixing this properly would + * require the vma::vm_flags to be protected by a separate + * lock taken after the i_mmap_lock + */ + + /* Skip non-applicable VMAs */ + if ((vm_flags & (VM_SHARED | VM_WRITE)) != + (VM_SHARED | VM_WRITE)) + continue; + + /* Warn on and skip VMAs whose flags indicate illegal usage */ + if (WARN_ON((vm_flags & (VM_HUGETLB | VM_IO)) != VM_IO)) + continue; + + /* Clip to the vma */ + vba = vma->vm_pgoff; + vea = vba + vma_pages(vma); + cba = first_index; + cba = max(cba, vba); + cea = first_index + nr; + cea = min(cea, vea); + + /* Translate to virtual address */ + start_addr = ((cba - vba) << PAGE_SHIFT) + vma->vm_start; + end_addr = ((cea - vba) << PAGE_SHIFT) + vma->vm_start; + if (start_addr >= end_addr) + continue; + + aas->base.mm = vma->vm_mm; + aas->vma = vma; + aas->start = end_addr; + aas->end = start_addr; + + mmu_notifier_range_init(&range, vma->vm_mm, + start_addr, end_addr); + mmu_notifier_invalidate_range_start(&range); + + /* Needed when we only change protection? */ + flush_cache_range(vma, start_addr, end_addr); + + /* + * We're not using tlb_gather_mmu() since typically + * only a small subrange of PTEs are affected. + */ + inc_tlb_flush_pending(vma->vm_mm); + + /* Should not error since aas->base.alloc == 0 */ + WARN_ON(apply_to_pfn_range(&aas->base, start_addr, + end_addr - start_addr)); + if (aas->end > aas->start) + flush_tlb_range(vma, aas->start, aas->end); + + mmu_notifier_invalidate_range_end(&range); + dec_tlb_flush_pending(vma->vm_mm); + } + i_mmap_unlock_read(mapping); + + return aas->total; +} + +/** + * apply_as_wrprotect - Write-protect all ptes in an address_space range + * @mapping: The address_space we want to write protect + * @first_index: The first page offset in the range + * @nr: Number of incremental page offsets to cover + * + * WARNING: This function should only be used for address spaces that + * completely own the pages / memory the page table points to. Typically a + * device file. + * + * Return: The number of ptes actually write-protected. Note that + * already write-protected ptes are not counted. + */ +unsigned long apply_as_wrprotect(struct address_space *mapping, + pgoff_t first_index, pgoff_t nr) +{ + struct apply_as aas = { + .base = { + .alloc = 0, + .ptefn = apply_pt_wrprotect, + }, + .total = 0, + }; + + return apply_as_range(mapping, &aas, first_index, nr); +} +EXPORT_SYMBOL(apply_as_wrprotect); + +/** + * apply_as_clean - Clean all ptes in an address_space range + * @mapping: The address_space we want to clean + * @first_index: The first page offset in the range + * @nr: Number of incremental page offsets to cover + * @bitmap_pgoff: The page offset of the first bit in @bitmap + * @bitmap: Pointer to a bitmap of at least @nr bits. The bitmap needs to + * cover the whole range @first_index..@first_index + @nr. + * @start: Pointer to number of the first set bit in @bitmap. + * is modified as new bits are set by the function. + * @end: Pointer to the number of the last set bit in @bitmap. + * none set. The value is modified as new bits are set by the function. + * + * Note: When this function returns there is no guarantee that a CPU has + * not already dirtied new ptes. However it will not clean any ptes not + * reported in the bitmap. + * + * If a caller needs to make sure all dirty ptes are picked up and none + * additional are added, it first needs to write-protect the address-space + * range and make sure new writers are blocked in page_mkwrite() or + * pfn_mkwrite(). And then after a TLB flush following the write-protection + * pick up all dirty bits. + * + * WARNING: This function should only be used for address spaces that + * completely own the pages / memory the page table points to. Typically a + * device file. + * + * Return: The number of dirty ptes actually cleaned. + */ +unsigned long apply_as_clean(struct address_space *mapping, + pgoff_t first_index, pgoff_t nr, + pgoff_t bitmap_pgoff, + unsigned long *bitmap, + pgoff_t *start, + pgoff_t *end) +{ + bool none_set = (*start >= *end); + struct apply_as_clean clean = { + .base = { + .base = { + .alloc = 0, + .ptefn = apply_pt_clean, + }, + .total = 0, + }, + .bitmap_pgoff = bitmap_pgoff, + .bitmap = bitmap, + .start = none_set ? nr : *start, + .end = none_set ? 0 : *end, + }; + unsigned long ret = apply_as_range(mapping, &clean.base, first_index, + nr); + + *start = clean.start; + *end = clean.end; + return ret; +} +EXPORT_SYMBOL(apply_as_clean);