From patchwork Thu Nov 19 14:41:43 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Daniel Vetter X-Patchwork-Id: 11917683 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-18.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5ED8BC8300E for ; Thu, 19 Nov 2020 14:43:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1F05420888 for ; Thu, 19 Nov 2020 14:43:24 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=ffwll.ch header.i=@ffwll.ch header.b="Mds0KKYR" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728372AbgKSOmj (ORCPT ); Thu, 19 Nov 2020 09:42:39 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37492 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728322AbgKSOmP (ORCPT ); Thu, 19 Nov 2020 09:42:15 -0500 Received: from mail-wm1-x341.google.com (mail-wm1-x341.google.com [IPv6:2a00:1450:4864:20::341]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id F0A76C0613CF for ; Thu, 19 Nov 2020 06:42:13 -0800 (PST) Received: by mail-wm1-x341.google.com with SMTP id w24so6983856wmi.0 for ; Thu, 19 Nov 2020 06:42:13 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ffwll.ch; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=rW60Jo5EYOrfW48enxn4HuDZHwz18Yu4cEXjV+kmxhI=; b=Mds0KKYR7OlWEldi1eh1ggSjTWLm8H299PjAEVopmaDX9SejYgx/bgXXgGqVeWoeAG umyXrkGdnXYA46wdpqDzfj7FH45aOUy77I+Qc8IUJ/53mNQ7N+2xlTMP9z4uAN8h2bBC AIcr+GU5pTJJ86QC2SIt8u/+0HuuTGtQwupxs= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=rW60Jo5EYOrfW48enxn4HuDZHwz18Yu4cEXjV+kmxhI=; b=o/t6B6jEGIKiRyGs2rqAFIm6YiyDWWIvXfIoohYu3PEqqoF2pmv8NbHaSRbKTdghrw 9GQzSMUCELj7QCQDHRUqn4CIi/dSAFYG7sV/eb47cwC3HOfI3qtcwo1QyF8tNH7xELRc qTBr/Mmgi4lGYZyFaPOEXdrgJiEtR/UNNybooUvpyA9Bvd7V5WKP1N36y5Yx1KdI98nf 01n4USDhDqUOU6JPCvLxyB9X9FTS7rbKPd6bMdCUX/UAWd8TirdQs7hWJHZ9aPN7EI2J gZlMxhTSD7wK8cJnp1DPQx8vkwyDV6w2iqncje73hk/KGFLUwN+RuFN/Q0BQ9AJGswM2 pqQA== X-Gm-Message-State: AOAM531WrYzIh7BSKF8SXX+Yke16J4B2U8ExeNwoN6KPYx3dJnesR6xY gXOnSGtTzsIh425W43ood1F1mw== X-Google-Smtp-Source: ABdhPJzDoO8vwM1uKLMMzDY63Xtv6UYaVCRPNtJiMLhNtXOdUD9Ea0qBkhZUQjS3C8qhP4NCGswHYA== X-Received: by 2002:a1c:a344:: with SMTP id m65mr5067390wme.77.1605796932701; Thu, 19 Nov 2020 06:42:12 -0800 (PST) Received: from phenom.ffwll.local ([2a02:168:57f4:0:efd0:b9e5:5ae6:c2fa]) by smtp.gmail.com with ESMTPSA id x63sm51292wmb.48.2020.11.19.06.42.11 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 19 Nov 2020 06:42:11 -0800 (PST) From: Daniel Vetter To: DRI Development , LKML Cc: kvm@vger.kernel.org, linux-mm@kvack.org, linux-arm-kernel@lists.infradead.org, linux-samsung-soc@vger.kernel.org, linux-media@vger.kernel.org, Daniel Vetter , Greg Kroah-Hartman , Daniel Vetter , Jason Gunthorpe , Kees Cook , Dan Williams , Andrew Morton , John Hubbard , =?utf-8?b?SsOpcsO0bWUgR2xpc3Nl?= , Jan Kara , Bjorn Helgaas , linux-pci@vger.kernel.org, "Rafael J. Wysocki" , Christian Brauner , "David S. Miller" , Michael Ellerman , Sourabh Jain , Mauro Carvalho Chehab , Nayna Jain Subject: [PATCH v6 14/17] sysfs: Support zapping of binary attr mmaps Date: Thu, 19 Nov 2020 15:41:43 +0100 Message-Id: <20201119144146.1045202-15-daniel.vetter@ffwll.ch> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20201119144146.1045202-1-daniel.vetter@ffwll.ch> References: <20201119144146.1045202-1-daniel.vetter@ffwll.ch> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org We want to be able to revoke pci mmaps so that the same access rules applies as for /dev/kmem. Revoke support for devmem was added in 3234ac664a87 ("/dev/mem: Revoke mappings when a driver claims the region"). The simplest way to achieve this is by having the same filp->f_mapping for all mappings, so that unmap_mapping_range can find them all, no matter through which file they've been created. Since this must be set at open time we need sysfs support for this. Add an optional mapping parameter bin_attr, which is only consulted when there's also an mmap callback, since without mmap support allowing to adjust the ->f_mapping makes no sense. Reviewed-by: Greg Kroah-Hartman Signed-off-by: Daniel Vetter Cc: Jason Gunthorpe Cc: Kees Cook Cc: Dan Williams Cc: Andrew Morton Cc: John Hubbard Cc: Jérôme Glisse Cc: Jan Kara Cc: Dan Williams Cc: linux-mm@kvack.org Cc: linux-arm-kernel@lists.infradead.org Cc: linux-samsung-soc@vger.kernel.org Cc: linux-media@vger.kernel.org Cc: Bjorn Helgaas Cc: linux-pci@vger.kernel.org Cc: Greg Kroah-Hartman Cc: "Rafael J. Wysocki" Cc: Christian Brauner Cc: "David S. Miller" Cc: Michael Ellerman Cc: Sourabh Jain Cc: Daniel Vetter Cc: Mauro Carvalho Chehab Cc: Nayna Jain Signed-off-by: Daniel Vetter --- fs/sysfs/file.c | 11 +++++++++++ include/linux/sysfs.h | 2 ++ 2 files changed, 13 insertions(+) diff --git a/fs/sysfs/file.c b/fs/sysfs/file.c index 96d0da65e088..9aefa7779b29 100644 --- a/fs/sysfs/file.c +++ b/fs/sysfs/file.c @@ -170,6 +170,16 @@ static int sysfs_kf_bin_mmap(struct kernfs_open_file *of, return battr->mmap(of->file, kobj, battr, vma); } +static int sysfs_kf_bin_open(struct kernfs_open_file *of) +{ + struct bin_attribute *battr = of->kn->priv; + + if (battr->mapping) + of->file->f_mapping = battr->mapping; + + return 0; +} + void sysfs_notify(struct kobject *kobj, const char *dir, const char *attr) { struct kernfs_node *kn = kobj->sd, *tmp; @@ -241,6 +251,7 @@ static const struct kernfs_ops sysfs_bin_kfops_mmap = { .read = sysfs_kf_bin_read, .write = sysfs_kf_bin_write, .mmap = sysfs_kf_bin_mmap, + .open = sysfs_kf_bin_open, }; int sysfs_add_file_mode_ns(struct kernfs_node *parent, diff --git a/include/linux/sysfs.h b/include/linux/sysfs.h index 2caa34c1ca1a..d76a1ddf83a3 100644 --- a/include/linux/sysfs.h +++ b/include/linux/sysfs.h @@ -164,11 +164,13 @@ __ATTRIBUTE_GROUPS(_name) struct file; struct vm_area_struct; +struct address_space; struct bin_attribute { struct attribute attr; size_t size; void *private; + struct address_space *mapping; ssize_t (*read)(struct file *, struct kobject *, struct bin_attribute *, char *, loff_t, size_t); ssize_t (*write)(struct file *, struct kobject *, struct bin_attribute *,