From patchwork Fri Oct 30 10:08:14 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Daniel Vetter X-Patchwork-Id: 11869035 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id CED1B139F for ; Fri, 30 Oct 2020 10:09:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A72CD22202 for ; Fri, 30 Oct 2020 10:09:28 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=ffwll.ch header.i=@ffwll.ch header.b="dMXZgQQ4" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726407AbgJ3KJ0 (ORCPT ); Fri, 30 Oct 2020 06:09:26 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50430 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726489AbgJ3KI7 (ORCPT ); Fri, 30 Oct 2020 06:08:59 -0400 Received: from mail-wr1-x442.google.com (mail-wr1-x442.google.com [IPv6:2a00:1450:4864:20::442]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5DA5AC0613D4 for ; Fri, 30 Oct 2020 03:08:59 -0700 (PDT) Received: by mail-wr1-x442.google.com with SMTP id t9so5753598wrq.11 for ; Fri, 30 Oct 2020 03:08:59 -0700 (PDT) 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=x64Pdy8p+ZGL0slSw+rtx7HFhuDJqqnGsdIVDlQDjdQ=; b=dMXZgQQ4GInuf9jrQbek8Tp4TJwmqWcWzEoGzN+XnEIIgNSKSXrrzWsVgCIz1j4mbw c+B42LT5fsWsIB7y68aybpNVUX+JyN3Td0Ws9EA48SWBfWCaf3zgE6G6thggoKs//hX0 Upru27GCrw83TFd3ijeyNjhXKU4N04Gf2K5U4= 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=x64Pdy8p+ZGL0slSw+rtx7HFhuDJqqnGsdIVDlQDjdQ=; b=NEPa66IZobG29cbsZ28UWc2eHcBiWEI9AfyQPUJlkNlu3bO30lhXTRIudNgP906yoq 72ULadrfUbsjRfiK/eBF6AiFmSoetYr/JCX3kJdPb80hW8MJkD3JLx9KP5Vx+yxlZha8 KAaKf47yz5lbgCiXl8dLYgsXd7+r+FefFaJN1qWPIGFTjvnlZfN8D0EdMWrOVWox6WQv Z2qFwIZwHu9QENTtRH+FhlIvUW5kZqQSjVuGU/C6tNxxQ6BRcHvYgO4NNdcfIh4R+3FR mjIA0VyLeZVORXoS8yjf7U8Wt/kjAZdSJvd276ijGbDqT0EdLx38ZXYQve8Qh4ERUdCd hH5Q== X-Gm-Message-State: AOAM532lX4SJLkMVQkYMc6SfGyg8Dfk01rvvdY+ikr7tymEZqgwICKuz wpBZqJpk4pjL1ObReynw5zEn2Q== X-Google-Smtp-Source: ABdhPJzxGFYoPzMG5L1cos4pmye64LCF8H+vRnUg6QzaFISM5lCoumobRT1BRbCyB6uhYpZ60pR1/g== X-Received: by 2002:a5d:4b12:: with SMTP id v18mr2021446wrq.259.1604052538157; Fri, 30 Oct 2020 03:08:58 -0700 (PDT) Received: from phenom.ffwll.local ([2a02:168:57f4:0:efd0:b9e5:5ae6:c2fa]) by smtp.gmail.com with ESMTPSA id v189sm4430947wmg.14.2020.10.30.03.08.56 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 30 Oct 2020 03:08:57 -0700 (PDT) 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 v5 14/15] sysfs: Support zapping of binary attr mmaps Date: Fri, 30 Oct 2020 11:08:14 +0100 Message-Id: <20201030100815.2269-15-daniel.vetter@ffwll.ch> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20201030100815.2269-1-daniel.vetter@ffwll.ch> References: <20201030100815.2269-1-daniel.vetter@ffwll.ch> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-samsung-soc@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 *,