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: 11869037 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 398A314B2 for ; Fri, 30 Oct 2020 10:09:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0F12722210 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 S1726019AbgJ3KJ0 (ORCPT ); Fri, 30 Oct 2020 06:09:26 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50426 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726484AbgJ3KI7 (ORCPT ); Fri, 30 Oct 2020 06:08:59 -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 5DF0FC0613D5 for ; Fri, 30 Oct 2020 03:08:59 -0700 (PDT) Received: by mail-wr1-x441.google.com with SMTP id b8so5837716wrn.0 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=cb8RUKYOajFA/CSz/6JMMZFlifInFxBUhPA2d59O2sTo0atuh/ESlAuiFB0QIWSK/M 6sY6q3/Oy14SZZmWG8mX7YZLkBUWVX5fUsdlIELR77G70QXEpEtiE55ddHPqRY36H1RM ToL7mdnXsoAU7F40Inx45gS6zQsESlyBU/lJwZUrpaYNjVul3sKASu70eIFstjFunXAr r24yRXaNkNLS5aaNdJ56z24WubNuDfunUHjtYojavCdak1EEAxW/2/h6poWxMc3dTVyV nr97aneS985OETjP7HfnOw/GDF+k0P0e62fSllEELPuCD8WKtlzTtVHjhcJo33GJQyiv R16g== X-Gm-Message-State: AOAM530+b4sbpGQu93yZb87wK4Uz7B8Hu4K7+xGh+ilBsSVd6bwHIDYS il5Y6rEwLTRDKpr3KUo4z/pWiw== 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-pci@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 *,