From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752804AbYIPFcQ (ORCPT ); Tue, 16 Sep 2008 01:32:16 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751376AbYIPFb7 (ORCPT ); Tue, 16 Sep 2008 01:31:59 -0400 Received: from sh.osrg.net ([192.16.179.4]:41247 "EHLO sh.osrg.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751335AbYIPFb6 (ORCPT ); Tue, 16 Sep 2008 01:31:58 -0400 Date: Tue, 16 Sep 2008 14:31:40 +0900 (JST) Message-Id: <20080916.143140.75515448.ryusuke@osrg.net> To: penberg@cs.helsinki.fi Cc: akpm@linux-foundation.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 18/27] nilfs2: pathname operations From: konishi.ryusuke@lab.ntt.co.jp In-Reply-To: <84144f020809151120u36338574y4577fa73ea3d222f@mail.gmail.com> References: <1221419304-18572-18-git-send-email-konishi.ryusuke@lab.ntt.co.jp> <1221419304-18572-19-git-send-email-konishi.ryusuke@lab.ntt.co.jp> <84144f020809151120u36338574y4577fa73ea3d222f@mail.gmail.com> X-Mailer: Mew version 4.2 on Emacs 21.4 / Mule 5.0 (SAKAKI) Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Pekka! On Mon, 15 Sep 2008 21:20:23 +0300, "Pekka Enberg" wrote: > Hi Ryusuke, > > On Sun, Sep 14, 2008 at 10:08 PM, Ryusuke Konishi > wrote: > > This adds pathname operations, most of which comes from the ext2 file > > system. > > > > Signed-off-by: Ryusuke Konishi > > +/* > > + * By the time this is called, we already have created > > + * the directory cache entry for the new file, but it > > + * is so far negative - it has no inode. > > + * > > + * If the create succeeds, we fill in the inode information > > + * with d_instantiate(). > > + */ > > +static int nilfs_create(struct inode *dir, struct dentry *dentry, int mode, > > + struct nameidata *nd) > > +{ > > + struct inode *inode; > > + struct nilfs_transaction_info ti; > > + int err, err2; > > + > > + err = nilfs_transaction_begin(dir->i_sb, &ti, 1); > > + if (err) > > + return err; > > + inode = nilfs_new_inode(dir, mode); > > + err = PTR_ERR(inode); > > + if (!IS_ERR(inode)) { > > + inode->i_op = &nilfs_file_inode_operations; > > + inode->i_fop = &nilfs_file_operations; > > + inode->i_mapping->a_ops = &nilfs_aops; > > + mark_inode_dirty(inode); > > + err = nilfs_add_nondir(dentry, inode); > > + } > > + err2 = nilfs_transaction_end(dir->i_sb, !err); > > OK, I don't understand this. The only way nilfs_transaction_end() can > fail is if we have NILFS_TI_SYNC set and we fail to construct the > segment. But why do we want to construct a segment if we don't commit? > > I guess what I'm asking is why don't we have a separate > nilfs_transaction_abort() function that can't fail for the erroneous > case to avoid this double error value tracking thing? > > Pekka Yeah, that's quite right. nilfs_transaction_end() should not call nilfs_construct_segment() in the error case, and this double error handling seems to be avoidable. The ``commit'' argument of nilfs_transaction_end() is insufficient because it does not cancel the commit state. I'd like to correct these error hanlings by adding nilfs_transaction_abort() as you told me. Thank you for the comment. Regards, Ryusuke