From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S942453AbdAIOeX (ORCPT ); Mon, 9 Jan 2017 09:34:23 -0500 Received: from mail-pg0-f68.google.com ([74.125.83.68]:33515 "EHLO mail-pg0-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932134AbdAIOeT (ORCPT ); Mon, 9 Jan 2017 09:34:19 -0500 Date: Mon, 9 Jan 2017 23:33:44 +0900 From: Sergey Senozhatsky To: Minchan Kim Cc: Jens Axboe , Hyeoncheol Lee , linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, Andrew Morton , Sergey Senozhatsky , Robert Jennings , Jerome Marchand Subject: Re: [RFC] blk: increase logical_block_size to unsigned int Message-ID: <20170109143344.GA753@tigerII.localdomain> References: <1483938267-8858-1-git-send-email-minchan@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1483938267-8858-1-git-send-email-minchan@kernel.org> User-Agent: Mutt/1.7.2 (2016-11-26) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On (01/09/17 14:04), Minchan Kim wrote: > Mostly, zram is used as swap system on embedded world so it want to do IO > as PAGE_SIZE aligned/size IO unit. For that, one of the problem was > blk_queue_logical_block_size(zram->disk->queue, PAGE_SIZE) made overflow > in *64K page system* so [1] changed it to constant 4096. > Since that, partial IO can happen so zram should handle it which makes zram > complicated[2]. > I thought that zram partial IO support is there because some file systems cannot cope with large logical_block_size. like FAT, for example. am I wrong? -ss