ubifs image file confusion!

[Artem Bityutskiy]

On Tue, 2008-05-13 at 20:41 +0800, Nancy wrote:
>    Cause I was writing ubi-util, sure I show this issue at UBI standpoint.
If you want me to understand you and properly answer, you should try to
formulate things better. I understand language difficulties and this is
all right. I just ask you to try better, may be re-reading what you have
composed and trying imagine me reading your mail and imagine which part
could be not very clear for me.

>    OK, what mkfs.ubifs for? generate image file used by ubiupdatevol.
OK.

> It should contain the necessary data. What is necessary data? at least
> the data should be writen down on the Nand flash. On the standpoint of
> UBI, those data should be mapped.  It does not make sense to contain
> data(LEBs which contents are all 0xFF).
OK.

>  ubiupdatevol have to play a
> trick to avoid writing those 0xFF to Nand.
OK.

>    As I fool understand which I have plase after that mail:
Cannot parse this sentence, sorry.

> > >        #ubiupdatevol /dev/ubi0_0 ubifs.img   also write the unmapped
> > > LEBs to Nand flash.
> > It does not write them, but it creates them if the image size is less
> > then amount of space on the volume. What else do you expect?
>    I do not mean that part of 0xFF.  I mean the unmapped part in the image file.
Cannot understand what we are talking about here. What
'ubiupdatevol /dev/ubi0_0 ubifs.img' doing is:
1. Wipes out whole volume ubi0_0 which technically means unmapping all
LEBs.
2. Puts date from ubifs.img to the volume, starting from LEB 0.
3. If the ubifs.img file is less than the ubi0_0 volume, some amount of
LEBs at the end will be unmapped.


> pls:
>       1. ubinize tool do not check whether vol_id or vol_name's
> uniqueness which may cause unexpected error.

OK, will be fixed but a bit later.

>       2. ubinize tool's volume size check do not aligned to LEB size.
Cannot parse this.

> I can't use an image file which taken up of its all volume space.
> eg. LEB size =258048  , .cfg defined vol size = 100MiB ,
> vfat.img(407LEBs)     fail
> it say something like the image file size exceed the volume size. I'm
> home now, can't plase the original error message here. sorry.
Sorry, do not understand this.

-- 
Best regards,
Artem Bityutskiy (Битюцкий Артём)