From patchwork Fri Nov 27 16:41:25 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Daniel Vetter X-Patchwork-Id: 11936795 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 C148CC8300F for ; Fri, 27 Nov 2020 16:43:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 76F2320657 for ; Fri, 27 Nov 2020 16:43:08 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=ffwll.ch header.i=@ffwll.ch header.b="PQkuXj5f" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731829AbgK0QmP (ORCPT ); Fri, 27 Nov 2020 11:42:15 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54058 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731830AbgK0QmO (ORCPT ); Fri, 27 Nov 2020 11:42:14 -0500 Received: from mail-wr1-x441.google.com (mail-wr1-x441.google.com [IPv6:2a00:1450:4864:20::441]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B71C9C0613D1 for ; Fri, 27 Nov 2020 08:42:13 -0800 (PST) Received: by mail-wr1-x441.google.com with SMTP id i2so6204749wrs.4 for ; Fri, 27 Nov 2020 08:42:13 -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=PQkuXj5frTE5y11eiKAgq79LrIZ8tE/zx4eh3eEZQp6giLCWCHkekWBtjZn+b6apiX OettDGs7KeV6c1u5GVEgBTyePxi+k0YgxvAkEqvC0lu/PHO5FoD5SaGsKYrsR8iraWxV gzEOq3melTr0FDtkd450cWQdzdipC9arwKkow= 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=DcCbbUWudsl667S29czSmDD0M9iHaIx4Zhly1GW51lxwthteHe4CdaWjHYIeZw6ktZ qFu5ERgQl8ZLZUfSIKrd6xHK9+0+FqGODlONA1oLeKx7nLgdwRhnWXzun8aFmRAn1fP2 VvEmwktGEh0ZuES2Iw8SioDlsKvhV1nu6fBMX9nAlYYNcGTuo1aiuuzHCNTcfvNB+sdN srcgplMz+6BHNCYbbY0aF05rST1mZgAXRT+BLyQy4aVfm0LikQyhjX2xJFYgQ+xKYoij jfSmdG7YRItYq5qXPHToWNX/U1R3fRp/mphPcyzHRGxpaduKT/lsDcOlCvfeCdy53gyF Bcog== X-Gm-Message-State: AOAM531BOgLWi/CisGWz4/K+1D1IyHhJa1JMVe+z3Xz7KNImJPQcjrs9 K8KenZ0lgJzog22Vqz4LSn61zg== X-Google-Smtp-Source: ABdhPJy7N8sWlvrZkrO6DwKDVYKhPGfBm7BDjLJVeT6c/8cd28+5xGF25PU+qwVqK2WiY3xNRptmuw== X-Received: by 2002:adf:f3d1:: with SMTP id g17mr11762819wrp.201.1606495332522; Fri, 27 Nov 2020 08:42:12 -0800 (PST) Received: from phenom.ffwll.local ([2a02:168:57f4:0:efd0:b9e5:5ae6:c2fa]) by smtp.gmail.com with ESMTPSA id q12sm14859078wrx.86.2020.11.27.08.42.11 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 27 Nov 2020 08:42:11 -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 v7 11/17] sysfs: Support zapping of binary attr mmaps Date: Fri, 27 Nov 2020 17:41:25 +0100 Message-Id: <20201127164131.2244124-12-daniel.vetter@ffwll.ch> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20201127164131.2244124-1-daniel.vetter@ffwll.ch> References: <20201127164131.2244124-1-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 *,