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=-2.1 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 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 C02D8C3A5A2 for ; Tue, 3 Sep 2019 15:37:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9434423431 for ; Tue, 3 Sep 2019 15:37:11 +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="iPZa9nn0" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728860AbfICPhK (ORCPT ); Tue, 3 Sep 2019 11:37:10 -0400 Received: from bombadil.infradead.org ([198.137.202.133]:53190 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728571AbfICPhK (ORCPT ); Tue, 3 Sep 2019 11:37:10 -0400 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:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=TOMcH7snttb2Sr7cqyYUxOSzNPnn0zJCorjl1PxxkD8=; b=iPZa9nn0+EclNXulN9PX55CfF gjiZ/RcbonRlNHqkBzmGEe6Ioj+rAZKWUTmZvc8doirxhztv7FprjyzD7VGiWIB7qATK55E7i7a1x TmDqOuFRVBJbmG60tr0ElwbLZ46pwJskgV7Cz8NNRFQitmpy5Nz/lO1P2FXCuvPwzYgXor8S0FMf6 LAmnu/Qk8ARcx6Ev1/WBOUwEB1FDGT6iVSDqwPmo763jvjWRJqLnfmylBY0Mx+wmdggFpEJOWd14L UHDHQLEhg+ERlFoN1IzFKJI+sahK6t1WEtjnYNVxM2f8AqkTLjGHcU8IooYs/dyfk3rjjLyTwS9xf nr5m+CE5w==; Received: from hch by bombadil.infradead.org with local (Exim 4.92 #3 (Red Hat Linux)) id 1i5Arg-0000dg-Ql; Tue, 03 Sep 2019 15:37:04 +0000 Date: Tue, 3 Sep 2019 08:37:04 -0700 From: Christoph Hellwig To: Gao Xiang Cc: Christoph Hellwig , Gao Xiang , Chao Yu , Greg Kroah-Hartman , linux-fsdevel@vger.kernel.org, devel@driverdev.osuosl.org, linux-erofs@lists.ozlabs.org, Chao Yu Subject: Re: [PATCH 00/21] erofs: patchset addressing Christoph's comments Message-ID: <20190903153704.GA2201@infradead.org> References: <20190802125347.166018-1-gaoxiang25@huawei.com> <20190901055130.30572-1-hsiangkao@aol.com> <20190902124645.GA8369@infradead.org> <20190902142452.GE2664@architecture4> <20190902152323.GB14009@infradead.org> <20190902155037.GD179615@architecture4> <20190903065803.GA11205@infradead.org> <20190903081749.GA89379@architecture4> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190903081749.GA89379@architecture4> User-Agent: Mutt/1.11.4 (2019-03-13) X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On Tue, Sep 03, 2019 at 04:17:49PM +0800, Gao Xiang wrote: > I implement a prelimitary version, but I have no idea it is a really > cleanup for now. The fact that this has to guess the block device address_space implementation is indeed pretty ugly. I'd much prefer to just use read_cache_page_gfp, and live with the fact that this allocates bufferheads behind you for now. I'll try to speed up my attempts to get rid of the buffer heads on the block device mapping instead.