From patchwork Fri Nov 27 16:41:23 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Daniel Vetter X-Patchwork-Id: 11936793 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 94057C6379D for ; Fri, 27 Nov 2020 16:43:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 46C06221EB for ; Fri, 27 Nov 2020 16:43:07 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=ffwll.ch header.i=@ffwll.ch header.b="U7CnpbD0" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731793AbgK0QmM (ORCPT ); Fri, 27 Nov 2020 11:42:12 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54048 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731765AbgK0QmL (ORCPT ); Fri, 27 Nov 2020 11:42:11 -0500 Received: from mail-wm1-x342.google.com (mail-wm1-x342.google.com [IPv6:2a00:1450:4864:20::342]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C613FC061A4F for ; Fri, 27 Nov 2020 08:42:10 -0800 (PST) Received: by mail-wm1-x342.google.com with SMTP id x22so5629330wmc.5 for ; Fri, 27 Nov 2020 08:42:10 -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=U7CnpbD00qEoN/vUsVW+I4243+W/JnXoGNjkeopzZQU5so09mhertht0Ptz/Y9CU97 QBJjqG6J8HVGWhflVJAnSEhJA51fquUA/rLUSiFGQ3D16s3hdHYPSCDYykR5ivgrpzt5 UNuqMwTHX4nMkYA9iGIVY8KW3+QGNck+OCdBk= 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=I8P2tbXL18MmQhpHNqcFt9cJhIh8OVOHgbE9h28+8w30rjKf4RRr+0IbbKtcdYUiwV AVmYLGieBNeSXvAVvMiv/1L2/DfA712QSO8NZnBBIkk2j0Hx0Odq0f/34Rkh8EMbEreK Hb/sufAyJLVQUCyqGL3eOAAmm1D71pJ63BJPU2svBfbEkWqqRUAzkhrwXynEZYWdy6PH J12y0rOKQnkRBjOB4LMAyGBCk1UV1R59h3jF3PVhTTobYhpdCRa9zLQZ/0MHDbnHHw9w Sj1UhbxaBrLYDjtytMRYymtosohMi1qE0R7XsC/lzho/c5Nlc3hwLYcOxf/vDA1wgLkQ 5mlA== X-Gm-Message-State: AOAM531VSr1wljZZd8qEuWjPOGOJPEhE67jEBMhO7yALm4ij79GbxtmK JWlI9vuXhR9H9oQBGLlrPTrEHw== X-Google-Smtp-Source: ABdhPJxKU2LEPA3ycZu0g6uNTdSP1FwFa6HvSU/jo43OGE9w8xBQTe6/Vk/r7mX9FCsKkcy0le5iyg== X-Received: by 2002:a7b:cbd1:: with SMTP id n17mr9963982wmi.186.1606495329592; Fri, 27 Nov 2020 08:42:09 -0800 (PST) Received: from phenom.ffwll.local ([2a02:168:57f4:0:efd0:b9e5:5ae6:c2fa]) by smtp.gmail.com with ESMTPSA id q12sm14859078wrx.86.2020.11.27.08.42.08 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 27 Nov 2020 08:42:08 -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 v7 09/17] /dev/mem: Only set filp->f_mapping Date: Fri, 27 Nov 2020 17:41:23 +0100 Message-Id: <20201127164131.2244124-10-daniel.vetter@ffwll.ch> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20201127164131.2244124-1-daniel.vetter@ffwll.ch> References: <20201127164131.2244124-1-daniel.vetter@ffwll.ch> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@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;