From mboxrd@z Thu Jan 1 00:00:00 1970 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=-3.6 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS autolearn=no 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 133F9C2BA1A for ; Sun, 26 Apr 2020 07:26:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E87E62071E for ; Sun, 26 Apr 2020 07:26:47 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="Re1ECLpO" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726143AbgDZH0o (ORCPT ); Sun, 26 Apr 2020 03:26:44 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56394 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1725847AbgDZH0o (ORCPT ); Sun, 26 Apr 2020 03:26:44 -0400 Received: from bombadil.infradead.org (bombadil.infradead.org [IPv6:2607:7c80:54:e::133]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 96806C061A0C; Sun, 26 Apr 2020 00:26:44 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=In-Reply-To:Content-Type:MIME-Version :References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=CWSwm8Yeluzm8cpwZm/62btaRJCyoviiCLbacfabnGM=; b=Re1ECLpOnjCxMnMxw3nbFwqX2n aoIEpiDwCOhSXjRFQsAtKAUzFPfcZvScmnluhdPrGcpB4A73YnCcAK3X1/Udnt463gXZiWTPz/hdY Zm1qsK/TTQvahB8trR8xHhgpUygnDRg+nIVFpopoPErU2kCehwboKE+gZgzOWx7tGiBfdqF+7XjLQ nXGbVkpLeDiFJyDIB00acjlEnat0Goyv5mEX0AfFgXOl9BLdSgCkmDQwkWJK/Ym/oifDtpOlRDYDp XopgAFXT0HVE//Q7QrX3iZhO0PVRR0c/B26jlIRviJj+L4KI9zh60oN87/iGag0hjjm6rgmN2bu1K JDzqUHOw==; Received: from hch by bombadil.infradead.org with local (Exim 4.92.3 #3 (Red Hat Linux)) id 1jSbgY-00048J-Cx; Sun, 26 Apr 2020 07:26:42 +0000 Date: Sun, 26 Apr 2020 00:26:42 -0700 From: Christoph Hellwig To: ira.weiny@intel.com Cc: linux-kernel@vger.kernel.org, Andrew Morton , Dan Williams , Thomas Bogendoerfer , "James E.J. Bottomley" , Helge Deller , Benjamin Herrenschmidt , Paul Mackerras , "David S. Miller" , Thomas Gleixner , Ingo Molnar , Borislav Petkov , x86@kernel.org, "H. Peter Anvin" , Dave Hansen , Andy Lutomirski , Peter Zijlstra , Chris Zankel , Max Filippov , linux-snps-arc@lists.infradead.org, linux-arm-kernel@lists.infradead.org, linux-csky@vger.kernel.org, linux-mips@vger.kernel.org, linux-parisc@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, sparclinux@vger.kernel.org, linux-xtensa@linux-xtensa.org Subject: Re: [PATCH 4/5] arch/kmap_atomic: Consolidate duplicate code Message-ID: <20200426072642.GB22024@infradead.org> References: <20200426055406.134198-1-ira.weiny@intel.com> <20200426055406.134198-5-ira.weiny@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200426055406.134198-5-ira.weiny@intel.com> X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Sender: linux-mips-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-mips@vger.kernel.org > diff --git a/arch/arc/mm/highmem.c b/arch/arc/mm/highmem.c > index 4db13a6b9f3b..1cae4b911a33 100644 > --- a/arch/arc/mm/highmem.c > +++ b/arch/arc/mm/highmem.c > @@ -53,11 +53,10 @@ void *kmap_atomic(struct page *page) > { > int idx, cpu_idx; > unsigned long vaddr; > + void *addr = kmap_atomic_fast(page); > > - preempt_disable(); > - pagefault_disable(); > - if (!PageHighMem(page)) > - return page_address(page); > + if (addr) > + return addr; Wouldn't it make sense to just move kmap_atomic itelf to common code, and call out to a kmap_atomic_high for the highmem case, following the scheme in kmap? Same for the unmap side. That might require to support kmap_atomic_prot everywhere first, which sounds like a really good idea anyway, and would avoid the need for strange workaround in drm.