From patchwork Fri Oct 9 07:59:32 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Daniel Vetter X-Patchwork-Id: 269185 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=-12.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, 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 921D0C352B8 for ; Fri, 9 Oct 2020 08:00:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4F5B922276 for ; Fri, 9 Oct 2020 08:00:54 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=ffwll.ch header.i=@ffwll.ch header.b="DVC+VHNw" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732784AbgJIIAu (ORCPT ); Fri, 9 Oct 2020 04:00:50 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49558 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732745AbgJIIAP (ORCPT ); Fri, 9 Oct 2020 04:00:15 -0400 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 1CCDCC0613D6 for ; Fri, 9 Oct 2020 01:00:15 -0700 (PDT) Received: by mail-wr1-x441.google.com with SMTP id h7so9268641wre.4 for ; Fri, 09 Oct 2020 01:00:15 -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=DPr3++TkgD7opBHxWri6P050gTocJAeikYQ/tt45kKI=; b=DVC+VHNwYKVtqSii5lIVeaydDB6BLYuTeAJ5rwW+S55nTxLLBIyrPBVsS/L9PHMkF1 q3uw+XyygTSKEzljnhrtd+uqW+UWrHLzIjTm4/9nOxCepU5EL5HwS+mIoRk0TD6zsvng eZRy5dYaQjR4QunmQxA3SCZhsE7Sk5d3j+0PQ= 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=DPr3++TkgD7opBHxWri6P050gTocJAeikYQ/tt45kKI=; b=a3yMXp8MwxYH0U45dK73cGTMQQ9NtV8vRw8qekRgmsmkqYP5YZiNUCXhnIypK1G+Q/ dLZLO9Il8VLQ7W4vyCaDmF97z92zVcfeWD3N0u4FtUN8wKSwMHLytdHA+QuhMMDLKqnR d4qCVHEgiHYKe2shbtbpPJ9+mgyeZ/5Hige4QOFaRMiNsu2vSewwrACOIYggI7d8EtfT J/WAasNKk/vXVQ5WvIrXhDlVuhDpjiQVUY5fy3J8qcYPj7x/T623RZ1vDOrgJWaaSLae jbJfIRKXc2hoVTknQVJMywb2YUu2FTzBvTMBKefy9nR1Ig005nHisH3tCippGzGIasKC 5KTw== X-Gm-Message-State: AOAM532VMsG7iBNyuSU4iSmKxJ1pExt4zER0MT/VrQClJoU8G6rw5juf e3CeVYPXUXhQwmfe1mwDtrtQeA== X-Google-Smtp-Source: ABdhPJxjabNt7y3Fk149R7K1e+u9DjBsacewwbIgtRCFyrwVNWJDFlQJblhvJ+EjdKe0cN5lfI2azA== X-Received: by 2002:adf:f50e:: with SMTP id q14mr6435975wro.56.1602230413759; Fri, 09 Oct 2020 01:00:13 -0700 (PDT) Received: from phenom.ffwll.local ([2a02:168:57f4:0:efd0:b9e5:5ae6:c2fa]) by smtp.gmail.com with ESMTPSA id u17sm11634118wri.45.2020.10.09.01.00.12 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 09 Oct 2020 01:00:13 -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, linux-s390@vger.kernel.org, Daniel Vetter , 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, Greg Kroah-Hartman , "Rafael J. Wysocki" , Christian Brauner , "David S. Miller" , Michael Ellerman , Sourabh Jain , Mauro Carvalho Chehab , Nayna Jain Subject: [PATCH v2 15/17] sysfs: Support zapping of binary attr mmaps Date: Fri, 9 Oct 2020 09:59:32 +0200 Message-Id: <20201009075934.3509076-16-daniel.vetter@ffwll.ch> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20201009075934.3509076-1-daniel.vetter@ffwll.ch> References: <20201009075934.3509076-1-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. 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 Reviewed-by: Greg Kroah-Hartman --- 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 eb6897ab78e7..9d8ccdb000e3 100644 --- a/fs/sysfs/file.c +++ b/fs/sysfs/file.c @@ -169,6 +169,16 @@ 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; @@ -240,6 +250,7 @@ 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 34e84122f635..a17a474d1601 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 *,