Received: by 2002:a25:ad19:0:0:0:0:0 with SMTP id y25csp2875699ybi; Thu, 18 Jul 2019 16:19:04 -0700 (PDT) X-Google-Smtp-Source: APXvYqxsbmPvvB9QzSp8UXTeEmdvELBRCMsXRXzbfXKfLT9aNdW8MLaV6AdQwMWmRZSfYcVafDGP X-Received: by 2002:a17:902:2ec5:: with SMTP id r63mr52367942plb.21.1563491944728; Thu, 18 Jul 2019 16:19:04 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1563491944; cv=none; d=google.com; s=arc-20160816; b=IC7PMSgt6A2XCCUN8sNAVnkLAAqUAC2vKX7/QzR4Y2yW2tN8ml4kzyNhHpIYMTHyYD AUjnCUuNZ23DdGiNUlgIMFzZ5afIg2yiJQGHEx1pqQh8sO2dsOH6Ij9IBh0WQ9eP4FgS 2+8AM4AjMMj9LC7LwzBfmoLVIenbkWYKgynKa0LSREO+403qU4rh78CJGheifLVGs/lK 6IA/4/gn4ABzdXbsm//RdkQxUAi+hVStz5CQWnqkqI9NEP9j0Rd8FrAYETR9cbR/69ad EMU9sKxD/Jme4D2lPGFFJO7fkW+qFXrR4o5+nivRhQvdZkMn4smGpwBlTwCdvnq90Ni4 GxvA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:user-agent:in-reply-to :content-disposition:mime-version:references:message-id:subject:cc :to:from:date; bh=vEt+wz3c7WN2as5gcq8hf4O7EwGf+Uu5PqhcYiYGnUM=; b=V6pqXGyoO+Z0UAQn9F0kgrsrk7v6C10QBkbjRWGvcdOXDxKi4NPfZY3MWf3HoVQAPs ZpCnyg+stxqzv7qIuGhKyJ21/w2NJXP/hPmUryvBDEi4EfSO6ykcSvywftFqYid8fORT 8gDos1hjdGRa0G4ushnbXtG7AOv1PtMdEyCkE+RSURXAMG52kv8zM7Nfl4vZuNWHwN6r pssupFD2WNXKB9hXA6hkwlGtfpOXB2jPNSpO+CBFbde2ghkXsMUIbOm27Sxuh9E8J9QX LgxNlvF5OgM5fS5P7IOQyE29Opvj+xqaZDRwNtOkTfYhbcOj1R9hzV/OiaAhI7ToxdA9 cbsQ== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id k22si2898008pfk.90.2019.07.18.16.18.49; Thu, 18 Jul 2019 16:19:04 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2391607AbfGRXRy (ORCPT + 99 others); Thu, 18 Jul 2019 19:17:54 -0400 Received: from zeniv.linux.org.uk ([195.92.253.2]:53880 "EHLO ZenIV.linux.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727972AbfGRXRy (ORCPT ); Thu, 18 Jul 2019 19:17:54 -0400 Received: from viro by ZenIV.linux.org.uk with local (Exim 4.92 #3 (Red Hat Linux)) id 1hoFeq-0002m1-6a; Thu, 18 Jul 2019 23:17:52 +0000 Date: Fri, 19 Jul 2019 00:17:52 +0100 From: Al Viro To: Bjorn Andersson Cc: Benjamin LaHaise , linux-fsdevel@vger.kernel.org, linux-aio@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] aio: Support read/write with non-iter file-ops Message-ID: <20190718231751.GV17978@ZenIV.linux.org.uk> References: <20190718231054.8175-1-bjorn.andersson@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190718231054.8175-1-bjorn.andersson@linaro.org> User-Agent: Mutt/1.11.3 (2019-02-01) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Jul 18, 2019 at 04:10:54PM -0700, Bjorn Andersson wrote: > Implement a wrapper for aio_read()/write() to allow async IO on files > not implementing the iter version of read/write, such as sysfs. This > mimics how readv/writev uses non-iter ops in do_loop_readv_writev(). IDGI. How would that IO manage to be async? And what's the point using aio in such situations in the first place?