From: "Theodore Ts'o" Subject: ext4-online-defrag-free-space-fragmentation.patch uses do_fsync() Date: Wed, 23 Jan 2008 08:55:17 -0500 Message-ID: Cc: Mingming Cao , Takashi Sato , Akira Fujita To: linux-ext4@vger.kernel.org Return-path: Received: from BISCAYNE-ONE-STATION.MIT.EDU ([18.7.7.80]:49587 "EHLO biscayne-one-station.mit.edu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752097AbYAWNzY (ORCPT ); Wed, 23 Jan 2008 08:55:24 -0500 Sender: linux-ext4-owner@vger.kernel.org List-ID: I was trying to build ext4 as a module, and ran into problems because the online defrag patch is calling do_fsync() which is *not* an exported symbol, and so can not be called from a module. Looking at what the routine is doing, there's no reason to call do_fsync(), and in fact depending on the journaling mode in use, it may not force a journal commit, which seems to be the goal of the code. Hence, I plan to merge the following fix into the the defrag-free-space-fragmentation patch, unless there are any objections from Takashi-San or Akira-San. Regards, - Ted diff --git a/fs/ext4/defrag.c b/fs/ext4/defrag.c index 4ef3dc0..19d2cfd 100644 --- a/fs/ext4/defrag.c +++ b/fs/ext4/defrag.c @@ -632,8 +632,9 @@ static int ext4_ext_defrag_victim(struct file *target_filp, } /* Sync journal blocks before reservation */ - if (do_fsync(target_filp, 0)) { - printk(KERN_ERR "defrag: failed do_fsync\n"); + ret = ext4_force_commit(sb); + if (ret) { + printk(KERN_ERR "defrag: failed do_fsync (%d)\n", ret); goto ERR; } }