A problem of porting jffs2 and mtd in kernel 2.4.18

A problem of porting jffs2 and mtd in kernel 2.4.18

[jianhung]

Hello,

    This is my first posting. We have a project to porting jffs2 and mtd in
    embedded system, the purpose is to use the NAND flash, and the kernel
    is 2.4.18. We find there are jffs2 and mtd source code in the kernel
    source code. So we just enable it ( use make menuconfig),and write a
    mtd driver...

    The good news is this works, we can add, delete a file and after power
    on again, the file still exist. Thanks for JFFS2 and MTD, but the
    problem comes....

    1. the mount time is too slow, so we try to update the source code in
       the kernel, but I don\\\'t know the version of jffs2 and mtd in the
       kernel source code now is, how do I know it ? And I don\\\'t know how
       to update it, I hope someone can tell me, I would appreciate your
       kindness.

    2. If I use ECC function, and some thing wrong happens. After I trace
       the source code, I find when I write a file, the jffs2 will write to
       the same nand flash page (although in different position of the same
       page) without erase first many times . So the ECC position in the
       spare area will be write many times. It is reasonable when I read
       this page next time, the ECC value is not equal to the value I
       writed in the last time. of course the ecc will error, is this a bug
       of this version in kernel 2.4.18? (if I don\\\'t use ECC function, the
       subsystem seems ok)
    
    3. I didn\\\'t follow the instruction of \\\"The Linux MTD, JFFS HOW TO\\\", so
       I didn\\\'t use the utility erase and mkfs.jffs. But this still works,
       is this reasonable ?

Best Regards,
Yoda 

Re: A problem of porting jffs2 and mtd in kernel 2.4.18

[Thomas Gleixner]

On Wed, 2004-12-15 at 17:00 +0800, jianhung@csie.nctu.edu.tw wrote:
>     1. the mount time is too slow, so we try to update the source code in
>        the kernel, but I don\\\'t know the version of jffs2 and mtd in the
>        kernel source code now is, how do I know it ? And I don\\\'t know how
>        to update it, I hope someone can tell me, I would appreciate your
>        kindness.
> 
>     2. If I use ECC function, and some thing wrong happens. After I trace
>        the source code, I find when I write a file, the jffs2 will write to
>        the same nand flash page (although in different position of the same
>        page) without erase first many times . So the ECC position in the
>        spare area will be write many times. It is reasonable when I read
>        this page next time, the ECC value is not equal to the value I
>        writed in the last time. of course the ecc will error, is this a bug
>        of this version in kernel 2.4.18? (if I don\\\'t use ECC function, the
>        subsystem seems ok)

JFFS2 on NAND in 2.4.18 is not working and buggy. 2.4.18 itself is buggy
too.

Read http://www.linux-mtd.infradead.org/#kernelversions

tglx

Re: A problem of porting jffs2 and mtd in kernel 2.4.18

[Subrahmanyam]

Hai jianhung,

I have project similar to yours, wherein In my target too we have a file 
system and mtd drivers stored in the flash which also consists of 
ieee1394firewire and usb drivers. In the flash in the target system we need 
to store a particular key/data in the target. This data shall be dynamically 
modifiable  by a user interface provided to the user in the host.

Since you almost similar to the platform, henceforth I request you to 
suggest me a suitable approach.

Thanks,
Subrahmanyam.

----- Original Message ----- 
From: <jianhung@csie.nctu.edu.tw>
To: <linux-mtd@lists.infradead.org>
Sent: Wednesday, December 15, 2004 02:30 PM
Subject: A problem of porting jffs2 and mtd in kernel 2.4.18


> Hello,
>
>    This is my first posting. We have a project to porting jffs2 and mtd in
>    embedded system, the purpose is to use the NAND flash, and the kernel
>    is 2.4.18. We find there are jffs2 and mtd source code in the kernel
>    source code. So we just enable it ( use make menuconfig),and write a
>    mtd driver...
>
>    The good news is this works, we can add, delete a file and after power
>    on again, the file still exist. Thanks for JFFS2 and MTD, but the
>    problem comes....
>
>    1. the mount time is too slow, so we try to update the source code in
>       the kernel, but I don\\\'t know the version of jffs2 and mtd in the
>       kernel source code now is, how do I know it ? And I don\\\'t know 
> how
>       to update it, I hope someone can tell me, I would appreciate your
>       kindness.
>
>    2. If I use ECC function, and some thing wrong happens. After I trace
>       the source code, I find when I write a file, the jffs2 will write to
>       the same nand flash page (although in different position of the same
>       page) without erase first many times . So the ECC position in the
>       spare area will be write many times. It is reasonable when I read
>       this page next time, the ECC value is not equal to the value I
>       writed in the last time. of course the ecc will error, is this a bug
>       of this version in kernel 2.4.18? (if I don\\\'t use ECC function, 
> the
>       subsystem seems ok)
>
>    3. I didn\\\'t follow the instruction of \\\"The Linux MTD, JFFS HOW 
> TO\\\", so
>       I didn\\\'t use the utility erase and mkfs.jffs. But this still 
> works,
>       is this reasonable ?
>
> Best Regards,
> Yoda
>
> ______________________________________________________
> Linux MTD discussion mailing list
> http://lists.infradead.org/mailman/listinfo/linux-mtd/ 

Re: A problem of porting jffs2 and mtd in kernel 2.4.18

[jianhung]

Sorry for bother you again,

   but it is difficult for us to update the kernel to 2.6.x version,
   we only can use kernel 2.4.x, what suggestion will you give ?
   
   Thank you very much ...

Best Regards,
Yoda




On 15.12.2004 17:47:19, Thomas Gleixner <tglx@linutronix.de> wrote:

>
>JFFS2 on NAND in 2.4.18 is not working and buggy. 2.4.18 itself is
>buggy
>too.
>
>Read http://www.linux-mtd.infradead.org/#kernelversions
>
>tglx
>
>
>