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Subject: Re: [Yaffs] i've another question about yaffs2_scan_chunk?
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If you skip some chunks in a block then that should be fine.
However... yaffs checks the first chunk in a block to determine if the block 
is used. If you skip that chunk then yaffs will think the block is empty and 
will not scan it.

On Saturday 31 March 2012 14:10:44 Ezio Zhang wrote:
> what i mean is that  i may modify something about yaffs.as a result,it will
> occurs that page 1 ,2 ,3 wrote,and page 4 is skipped ,and then write the
> left which does not occurs in current yaffs.if this happens,can yaffs
> handle it ?
>
> On 2012-03-29 17:55, Charles Manning wrote:
> > On Thursday 29 March 2012 13:58:05 Ezio Zhang wrote:
> > > when start up,yaffs scan every chunk of a block that the summary not
> > > written.
> > > when it read the chunk's oob,if it is an empty chunk,the tags it read
>
> if
>
> > > full of 0xff,so the flag chunk_used should not be 0 and the judgement
>
> of
>
> > > "if (!tag.chunk_used)" should never enter, am i right?
> >
> > Erased flash starts off 0xff and can then be changed by setting 1 bits to
>
> 0
>
> > bits.
> >
> > If the tags are full of 0xff then chunk_used should be 0.
> >
> > > so in my understanding ,the function dev->param.read_chunk_tags_fn
>
> shoud do
>
> > > something rather than copy data from flash?
> > >
> > > and when writing data to flash,i cannot skip one or more chunks then
>
> write
>
> > > another one?
> >
> > I don't understand quite what you mean here can you give a slightly more
> > detailed descriprion.
> >
> > > thansk very much.
> > > ----
> > > Regards,
> > > Ezio.
>
> ----
> Regards,
> Ezio.