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Date: Wed, 05 Mar 2008 00:20:26 +0800
From: shizheng <neversetsun@ustc.edu>
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Cc: Charles Manning <manningc2@actrix.gen.nz>
Subject: [Yaffs] Source code mismatching development notes of Yaffs2?
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I'm viewing the latest source from cvs and I've got
a few questions about Yaffs2, especially when I compared
the code to the development notes(http://www.yaffs.net/node/38):

1. tag information stored in NAND oob
In the development notes, it says Yaffs2 has these tag information
including blockState, chunkId, objectId, nBytes, blockSequence, tagsEcc
and ecc.
But in yaffs_packedtags2.h, it defines
typedef struct {
unsigned sequenceNumber;
unsigned objectId;
unsigned chunkId;
unsigned byteCount;
} yaffs_PackedTags2TagsPart;

typedef struct {
yaffs_PackedTags2TagsPart t;
yaffs_ECCOther ecc;
} yaffs_PackedTags2;

and blockState and ecc on data are missing. I have no idea
about the MTD layer of linux, so I don't know whether the
two tags are handled by MTD.


2. The file $(SRC_ROOT)/patches/yaffs_mtdif2.c isn't useful, is it?
I have checkouted the source code, and done make/insmod directly on linux
without merging Yaffs into kernel tree.
The module works well without any patch when simple file operation is tested
on NANDSim(2kB page, 64B oob, 512MB chipsize).

best wishes, shizheng