Re: JFFS2 mount time

Artem B. Bityuckiy
2004-10-20T15:53:54Z

Ferenc Havasi wrote:
> The reason is the following: the summary node is at the end of the erase
> block, and it has not fixed size (its size depends on the information it
> stores).
>
> The main advantage of using summary node is to avoid the original
> scanning method. So we cannot use the original full-scanning method to
> determine the begining of the summary node (using only
> JFFS2_NODETYPE_INODE_SUM).
>
> Our method is the following:
> - read some bytes at the end of the erase block
> - if the last word is JFFS2_SUM_MAGIC than we will almost sure that it
> is an erase block which has summary
> - the word before this magic is the length of the node
> - using this length we can check that it is really a
> JFFS2_NODETYPE_INODE_SUM node, and process it
>
> I can't image more effective method to determine the begining of the
> summary node. (if you have better suggestion...) And because the magic
> is inside of the summary node I think it is fit to the philosophy of
> JFFS2 - but a little bit tricky.
Ok, I got it. I was wrong, sorry.

--
Best Regards,
Artem B. Bityuckiy,
St.-Petersburg, Russia.