From patchwork Wed Oct 21 08:56:52 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Daniel Vetter X-Patchwork-Id: 11848663 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 AE73C1744 for ; Wed, 21 Oct 2020 08:58:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 92B232227F for ; Wed, 21 Oct 2020 08:58:05 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=ffwll.ch header.i=@ffwll.ch header.b="Q5xIQ5ZZ" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2502386AbgJUI6F (ORCPT ); Wed, 21 Oct 2020 04:58:05 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41486 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2502379AbgJUI5Y (ORCPT ); Wed, 21 Oct 2020 04:57:24 -0400 Received: from mail-wr1-x443.google.com (mail-wr1-x443.google.com [IPv6:2a00:1450:4864:20::443]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9D028C0613E6 for ; Wed, 21 Oct 2020 01:57:22 -0700 (PDT) Received: by mail-wr1-x443.google.com with SMTP id e17so2017154wru.12 for ; Wed, 21 Oct 2020 01:57:22 -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=uPFBW3zdBbgXKQwmFhj6n2htyRlDiIM2JKOjMDR2Svk=; b=Q5xIQ5ZZYYOT58QTfrI5br9Ppx/bLZ105j8P0fIicibYOu5IC1Sg/+iyIB7NDvjNKa v8dXdU35mjbOyyP8u0IJ7eEZ+vL/X1lNG63n9af15UXY4ydu5XizX8BQwljv+vmiyhWM HFmJ5amWKsGB1BdrFdTO0WHgPqyFGMOuvguGg= 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=uPFBW3zdBbgXKQwmFhj6n2htyRlDiIM2JKOjMDR2Svk=; b=l6+Qy8TpTfcptvvn2Ds5KNB29eypUf3dGWjUvDPd3nLD5kqsgeKlGVESmB+pC7ukP8 fQcqtgZhy0b99ayRMybyfv8e5PYPbcWb5dLILZ3QxvljAYGCme2TS56/XjUkLuyzLhEH WK5wy6nXqFLsiWkNeR+Sp2Xm4Z7foq2gdnG+1OAkH/7G43S4ufm5y/yX6r5Cnq16N30I ZiWcCG6NbyB4ic24BY1z+ONDcqUO4/YYJ1JMsWpSpNm39SnRSwsfv4QXctlGHj2Yqqp3 dLYfZg+hBWOac+xDClpHmgQCyi8ZAWerqWNHNUdY53UYpME5gVupSCdbpavNr9gav8DJ 5FmQ== X-Gm-Message-State: AOAM531DKfIoZo0AmLn8hSLIuEx5kLa453MpowEpnkl4OTi+OGKcn3LD E33QjXJYloP3T6YZFJ5TtAd21A== X-Google-Smtp-Source: ABdhPJy8GRdMv9VFxpslmlWygSQvuKUEKPEZC0G0JfmHSUQJEjAtWYN/WzAaxZWK8SwF8l2Bb92lIg== X-Received: by 2002:a5d:6a85:: with SMTP id s5mr3550223wru.90.1603270641395; Wed, 21 Oct 2020 01:57:21 -0700 (PDT) Received: from phenom.ffwll.local ([2a02:168:57f4:0:efd0:b9e5:5ae6:c2fa]) by smtp.gmail.com with ESMTPSA id q8sm2675939wro.32.2020.10.21.01.57.20 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 21 Oct 2020 01:57:20 -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 , Daniel Vetter Subject: [PATCH v3 13/16] /dev/mem: Only set filp->f_mapping Date: Wed, 21 Oct 2020 10:56:52 +0200 Message-Id: <20201021085655.1192025-14-daniel.vetter@ffwll.ch> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20201021085655.1192025-1-daniel.vetter@ffwll.ch> References: <20201021085655.1192025-1-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 Signed-off-by: Daniel Vetter Reviewed-by: Dan Williams --- drivers/char/mem.c | 1 - 1 file changed, 1 deletion(-) diff --git a/drivers/char/mem.c b/drivers/char/mem.c index abd4ffdc8cde..5502f56f3655 100644 --- a/drivers/char/mem.c +++ b/drivers/char/mem.c @@ -864,7 +864,6 @@ 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;