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: 11917645 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=-16.5 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 90DFCC6379F for ; Thu, 19 Nov 2020 14:42:23 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 2D252246DE for ; Thu, 19 Nov 2020 14:42:23 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=ffwll.ch header.i=@ffwll.ch header.b="Mds0KKYR" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2D252246DE Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=ffwll.ch Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 41A506E588; Thu, 19 Nov 2020 14:42:16 +0000 (UTC) Received: from mail-wm1-x343.google.com (mail-wm1-x343.google.com [IPv6:2a00:1450:4864:20::343]) by gabe.freedesktop.org (Postfix) with ESMTPS id 5A4826E542 for ; Thu, 19 Nov 2020 14:42:14 +0000 (UTC) Received: by mail-wm1-x343.google.com with SMTP id a65so6981972wme.1 for ; Thu, 19 Nov 2020 06:42:14 -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=mjBt8i/Jizv7zehnYR+EFj83dunYQEh/bKWP6zQ2SRwiyIN/4P4IluyCLXW+osUmiS Mx8QAtYEMRftbN3khh93EdaxQyCyLCSnTnA99e+/16/uNhHyLMwycRkw6zThHuAq/bId jc62SA17bXttUlra6sXZeUD9RIhXZWZzaJlp0LDE1z5raHNFSGaVTTuvdr/xL3jxPtHJ hx6jkKpy0mUW40lBnzEBSXam1zuLFgVtlDhbF5+LbuzxL7CBFx/h0oi2/DqUAXjVEM0y UQfnsjh4EWozxmVgZQ2AKf/7SpnGOnM6lJxnF0T180E6ew0rhYy29rVMQITMl/QsItp5 KTKg== X-Gm-Message-State: AOAM533YQdvyRQg50ZAT6m9AXSJyigoRIxCw06H6R4vsDbON5/PsUyeW XI8WKRz8sCLekS6RCN4UtdvnVAohK7+5zA== 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 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 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Jan Kara , kvm@vger.kernel.org, "Rafael J. Wysocki" , Daniel Vetter , linux-mm@kvack.org, Daniel Vetter , Christian Brauner , linux-samsung-soc@vger.kernel.org, Mauro Carvalho Chehab , Michael Ellerman , Nayna Jain , Jason Gunthorpe , linux-pci@vger.kernel.org, linux-media@vger.kernel.org, Kees Cook , John Hubbard , =?utf-8?b?SsOpcsO0bWUgR2xpc3Nl?= , Bjorn Helgaas , Dan Williams , linux-arm-kernel@lists.infradead.org, Greg Kroah-Hartman , Sourabh Jain , Andrew Morton , "David S. Miller" Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" 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 *,