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=-0.6 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,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 61A9EC433E0 for ; Tue, 16 Jun 2020 07:30:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2C97C20734 for ; Tue, 16 Jun 2020 07:30:03 +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="mX7KVS76" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725911AbgFPHaC (ORCPT ); Tue, 16 Jun 2020 03:30:02 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53934 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725710AbgFPHaC (ORCPT ); Tue, 16 Jun 2020 03:30:02 -0400 Received: from bombadil.infradead.org (bombadil.infradead.org [IPv6:2607:7c80:54:e::133]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2E689C05BD43 for ; Tue, 16 Jun 2020 00:30:02 -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=hRLjeXbeNz86qwreVK3h2qFmY9Q9Ni6dZ5nLmd1OMuM=; b=mX7KVS76k+LeNkfNMXE2F/jKKE 1EoMutiNBzoYUo0bpUxEklRYY9PF+S9FdcKjeAA4BpeSsVEF9gUMwIkfKeITHWSDhuPTDK0Tp2pN2 /Ifci+UYf9KLgJNe8yLl3HgjE9PwnIycGYqVQdSbbifTTihqXozjDX9POAAy9r55iPXu2ZLnLSPga /ekr2BpvT9QF8qPZi3L4q5hYgz4L17/+OW2LiVGm8nxnPj23aNoeOtLzbO9TKqF0rYou2QS1rdn2r dIwqNwVWNugCk8vYneZEZzPghSEkwVtZnPCQq9Y/DiSsR0AifAAPxXJYMyMMzXo/mO/f4w1rBsmEa vqNLZ/bA==; Received: from hch by bombadil.infradead.org with local (Exim 4.92.3 #3 (Red Hat Linux)) id 1jl62d-00083Q-Fh; Tue, 16 Jun 2020 07:29:55 +0000 Date: Tue, 16 Jun 2020 00:29:55 -0700 From: Christoph Hellwig To: Harshad Shirwadkar Cc: linux-block@vger.kernel.org, tytso@mit.edu Subject: Re: [PATCH] block: add split_alignment for request queue Message-ID: <20200616072955.GA30385@infradead.org> References: <20200616005633.172804-1-harshadshirwadkar@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200616005633.172804-1-harshadshirwadkar@gmail.com> X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On Mon, Jun 15, 2020 at 05:56:33PM -0700, Harshad Shirwadkar wrote: > This feature allows the user to control the alignment at which request > queue is allowed to split bios. Google CloudSQL's 16k user space > application expects that direct io writes aligned at 16k boundary in > the user-space are not split by kernel at non-16k boundaries. That is a completely bogus assumptions and people who think they can make that assumption should not be allowed to write software. Can we stop this crap now please?