Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753687AbaBFGlO (ORCPT ); Thu, 6 Feb 2014 01:41:14 -0500 Received: from mail-qc0-f169.google.com ([209.85.216.169]:35228 "EHLO mail-qc0-f169.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751713AbaBFGlM (ORCPT ); Thu, 6 Feb 2014 01:41:12 -0500 MIME-Version: 1.0 In-Reply-To: <87txcfudzu.fsf@devron.myhome.or.jp> References: <1387953050-2692-1-git-send-email-linkinjeon@gmail.com> <87ioswx1xq.fsf@devron.myhome.or.jp> <87y51rue2a.fsf@devron.myhome.or.jp> <87txcfudzu.fsf@devron.myhome.or.jp> Date: Thu, 6 Feb 2014 15:41:11 +0900 Message-ID: Subject: Re: [PATCH v3 1/6] fat: add i_disksize to represent uninitialized size From: Namjae Jeon To: OGAWA Hirofumi Cc: akpm@linux-foundation.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, Namjae Jeon , Amit Sahrawat Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2014-02-04, OGAWA Hirofumi : > OGAWA Hirofumi writes: > >>>> Don't we need to update ->i_disksize after cont_write_begin()? >>> We don't need to update i_disksize after cont_write_begin. >>> It is taken care by the fat_get_block after the allocation. >>> For all write paths we align the mmu_private and i_disksize from >>> fat_fill_inode and fat_get_block. >> >> fat_fill_inode() just set i_disksize to i_size. So, it is not aligned by >> cluster size or block size. >> >> E.g. ->mmu_private = 500. Then, cont_write_begin() can set ->mmu_private >> to 512 on some case. In this case, fat_get_block() will not be called, >> because no new allocation. >> >> If this is true, it would be possible to have ->mmu_private == 512 and >> ->i_disksize == 500. >> >> I'm missing something? > > BTW, even if above was right, I'm not checking whether updating > ->i_disksize after cont_write_begin() is right fix or not. I understand your concern. these can be mismatched. But, when checking your doubt, I can not find any side effect. I think that there is no issue regardless of alignment of two value, in the cont_write_begin. Could you please share any point I am missing ? If you suggest checking point or test method, I can check more and share the result. Thanks OGAWA. > -- > OGAWA Hirofumi > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/