From patchwork Thu Nov 19 14:41:41 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Daniel Vetter X-Patchwork-Id: 11917807 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 9DFA9C8301D for ; Thu, 19 Nov 2020 14:43:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4B92420888 for ; Thu, 19 Nov 2020 14:43:27 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=ffwll.ch header.i=@ffwll.ch header.b="CIIgMEJ/" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728393AbgKSOnB (ORCPT ); Thu, 19 Nov 2020 09:43:01 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37482 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728281AbgKSOmM (ORCPT ); Thu, 19 Nov 2020 09:42:12 -0500 Received: from mail-wr1-x444.google.com (mail-wr1-x444.google.com [IPv6:2a00:1450:4864:20::444]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DE22BC061A52 for ; Thu, 19 Nov 2020 06:42:10 -0800 (PST) Received: by mail-wr1-x444.google.com with SMTP id k2so6743035wrx.2 for ; Thu, 19 Nov 2020 06:42:10 -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=lUo9ncFU/nKq3MG4mWQrX8BX1Csq/yukMRd1xs72MQA=; b=CIIgMEJ/YZCJYqrr/Qtw//Z/EuYS19MxKYSZBAuaNm2O4riC4ia7lWBoP9fdOxE899 lfrakfIMVKfanEOJTQM/T9AeH3p6C/ndGvDvgquoWvteonENyQO4m2trca3rvVUBYdrV pqSf5p+4Iw5KW2ru9wTswKE3C26aax9R920gc= 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=lUo9ncFU/nKq3MG4mWQrX8BX1Csq/yukMRd1xs72MQA=; b=IsJKptJrmfmIRHHA6Z97GDluUjrzaXA0WtpoP+1bhni4sGqoIoW/LVd/UQ9tCEfLXf as4eM20VI5fMPWZ82QoG78qbjgXk2P5Ec8xlOZc/qI5dm1U5hmvMRzEAEXPpLxcsvg1D mvJzC1W+xAMkB4gbQgs6+Y3TuvpqdJfktQg8+uwfjcYnp8cWL1cARa9HAcgzg67w79FU 8RXEGPS2pwATRrxkiA71FJmFQ5K4L+U7gQJHGAxVXqbhBD2Ls/XEX32bDo79ygYkiblH J9sG+7GeFMQle5l+OtxkxpmNB6scgkastBxEmF3B8Ev8ogH0iUKVonoUhI9UHgeYImB8 NiHA== X-Gm-Message-State: AOAM531+RnkgQbt9YuKv+dI1k+JlxVUNg/iRr13IczqLpvyYb02frHfl nYkE34iqPIn+w5wvDBjBnaxDSQ== X-Google-Smtp-Source: ABdhPJwk5Y7yKnIhKFhsy0JLp99xQ3IuhlAonQX0yhhkN3nOXvFaqvGXi/lZAmUY0jINVS3Y2iOPTg== X-Received: by 2002:adf:f7c7:: with SMTP id a7mr11488760wrq.347.1605796929676; Thu, 19 Nov 2020 06:42:09 -0800 (PST) Received: from phenom.ffwll.local ([2a02:168:57f4:0:efd0:b9e5:5ae6:c2fa]) by smtp.gmail.com with ESMTPSA id x63sm51292wmb.48.2020.11.19.06.42.08 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 19 Nov 2020 06:42:08 -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 , Daniel Vetter , Jason Gunthorpe , Kees Cook , Dan Williams , Andrew Morton , John Hubbard , =?utf-8?b?SsOpcsO0bWUgR2xpc3Nl?= , Jan Kara Subject: [PATCH v6 12/17] /dev/mem: Only set filp->f_mapping Date: Thu, 19 Nov 2020 15:41:41 +0100 Message-Id: <20201119144146.1045202-13-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 Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org When we care about pagecache maintenance, we need to make sure that both f_mapping and i_mapping point at the right mapping. But for iomem mappings we only care about the virtual/pte side of things, so f_mapping is enough. Also setting inode->i_mapping was confusing me as a driver maintainer, since in e.g. drivers/gpu we don't do that. Per Dan this seems to be copypasta from places which do care about pagecache consistency, but not needed. Hence remove it for slightly less confusion. 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 Reviewed-by: Dan Williams Signed-off-by: Daniel Vetter --- drivers/char/mem.c | 1 - 1 file changed, 1 deletion(-) diff --git a/drivers/char/mem.c b/drivers/char/mem.c index 94c2b556cf97..7dcf9e4ea79d 100644 --- a/drivers/char/mem.c +++ b/drivers/char/mem.c @@ -891,7 +891,6 @@ static int open_port(struct inode *inode, struct file *filp) * revocations when drivers want to take over a /dev/mem mapped * range. */ - inode->i_mapping = devmem_inode->i_mapping; filp->f_mapping = inode->i_mapping; return 0;