From mboxrd@z Thu Jan  1 00:00:00 1970
From: =?gb2312?B?1cW+/M6w?= <zhangjw@ict.ac.cn>
Subject: A question about ext3 journal
Date: Thu, 25 Jan 2007 16:47:33 +0800
Message-ID: <002701c7405d$7573ad80$0b0b0a0a@ictzhangjw>
References: <20070124202107.4788d802.akpm@osdl.org>
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Hi all
	I think there is a problem about journal in ext3.
	in linux-2.6.17/include/linux/ext3_jbd.h
/* Define the number of blocks we need to account to a transaction to
 * modify one block of data.
 * 
 * We may have to touch one inode, one bitmap buffer, up to three
 * indirection blocks, the group and superblock summaries, and the data
 * block to complete the transaction.  */

#define EXT3_SINGLEDATA_TRANS_BLOCKS	8U
The indirection blocks' modification also need their bitmap buffer and the
group summaries be modified, I think. So the block count should be 8U + 3*2;

Additionally, the journal operations in namei.c or inode.c also have the
problem like that.

Am I right? or misunderstand?  

	cheers, zhangjw