help request, jffs2 fs files get lost

help request, jffs2 fs files get lost

[Angelo Dureghello]

Hi all,

i am looking for some help on an issue with jffs2: i can create jffs2 fs, mount, store edit/write some files, unmount, 
but in a next mount i find no more files/dirs.

MTD probe detect correctly my flash, the chip allows erase sectors of 4KB, or blocks of 64KB. MTD shows correctly a 0x1000 erase size.

/ # / # cat /proc/mtd
dev:    size   erasesize  name
mtd0: 00010000 00001000 "Colilo (64K)"
mtd1: 002f0000 00001000 "Kernel+ROMfs (3008K)"
mtd2: 00100000 00001000 "JFFS2 (1024K)"  <--- want to use this partition only as jffs2 to store non volatile data
mtd3: 0009d000 00001000 "ROMfs"


So from uClinux, i try to prepare the jffs2 fs:

# eraseall /dev/mtd2
erased 1024 Kibyte @ 0 -- 100% complete.

cat /dev/mtd2    i see the flash has been cleared

then i create a folder "backup" in /var with some files and try to crete the jffs2 fs:

mkfs.jffs2 -d backup -o jffs2.img

cp /deV/mtd2 jffs2.img

Then i just mount/umount the device, but i get often the issue decribed.

Any help is really appreciated.

many thanks
angelo

Re: help request, jffs2 fs files get lost

[Ricard Wanderlof]

On Sun, 1 May 2011, Angelo Dureghello wrote:

> So from uClinux, i try to prepare the jffs2 fs:
>
> # eraseall /dev/mtd2
> erased 1024 Kibyte @ 0 -- 100% complete.
>
> cat /dev/mtd2    i see the flash has been cleared
>
> then i create a folder "backup" in /var with some files and try to crete the jffs2 fs:
>
> mkfs.jffs2 -d backup -o jffs2.img
>
> cp /deV/mtd2 jffs2.img

If this is in fact what you're doing, you're overwriting your jffs2.img 
file with the all-ff's contents of the newly erased /dev/mtd2. Swap the 
two arguments instead.

/Ricard
-- 
Ricard Wolf Wanderlöf                           ricardw(at)axis.com
Axis Communications AB, Lund, Sweden            www.axis.com
Phone +46 46 272 2016                           Fax +46 46 13 61 30

Re: help request, jffs2 fs files get lost

[angelo]

On 02/05/2011 08:55, Ricard Wanderlof wrote:
>
> On Sun, 1 May 2011, Angelo Dureghello wrote:
>
>> So from uClinux, i try to prepare the jffs2 fs:
>>
>> # eraseall /dev/mtd2
>> erased 1024 Kibyte @ 0 -- 100% complete.
>>
>> cat /dev/mtd2    i see the flash has been cleared
>>
>> then i create a folder "backup" in /var with some files and try to 
>> crete the jffs2 fs:
>>
>> mkfs.jffs2 -d backup -o jffs2.img
>>
>> cp /deV/mtd2 jffs2.img
>
> If this is in fact what you're doing, you're overwriting your 
> jffs2.img file with the all-ff's contents of the newly erased 
> /dev/mtd2. Swap the two arguments instead.
>
> /Ricard

Hi Ricard,
sorry, was late and just appended a bad had-written text,

i generally do "cp jffs2.img /dev/mtd2", and after mounting mtdblock2 i 
see correctly the root tree.

I did some other tests:
if i mount the new created jffs2 and unmount it, nothing is lost.
If i mount it, open a file, append some text, close it and unmount, then 
at the next mount everything is disapperaed (checking mtd2, all is set 
to 0xff).

Saving modified files i notice a warning:
Writing files is also notice some MTD debug trace, maybe an error:
Node totlen on flash (0xffffffff) != totlen from node ref (0x00000074)


many thanks,
angelo


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Re: help request, jffs2 fs files get lost

[Ricard Wanderlof]

On Mon, 2 May 2011, angelo wrote:

> If this is in fact what you're doing, you're overwriting your jffs2.img file with the all-ff's contents of the newly erased /dev/mtd2. Swap the two arguments instead.
>
> sorry, was just a bad had-written text,
> i generally do "cp jffs2.img /dev/mtd2", and after mounting mtdblock2 i see correctly the root tree.
>
> I did some other tests:
> if i mount the new created jffs2 and unmount it, nothing is lost.
> If i mount it, open a file, append some text, close it and unmount, then at the next mount everything is disapperaed (checking mtd2, all is set to 0xff).
>
> Saving modified files i notice a warning:
> Writing files is also notice some MTD debug trace, maybe an error:
> Node totlen on flash (0xffffffff) != totlen from node ref (0x00000074)

Out of curiosity, what exactly is the type of flash you are using?

/Ricard
-- 
Ricard Wolf Wanderlöf                           ricardw(at)axis.com
Axis Communications AB, Lund, Sweden            www.axis.com
Phone +46 46 272 2016                           Fax +46 46 13 61 30

Re: help request, jffs2 fs files get lost

[angelo]

On 02/05/2011 10:58, Ricard Wanderlof wrote:
>
> On Mon, 2 May 2011, angelo wrote:
>
>> If this is in fact what you're doing, you're overwriting your 
>> jffs2.img file with the all-ff's contents of the newly erased 
>> /dev/mtd2. Swap the two arguments instead.
>>
>> sorry, was just a bad had-written text,
>> i generally do "cp jffs2.img /dev/mtd2", and after mounting mtdblock2 
>> i see correctly the root tree.
>>
>> I did some other tests:
>> if i mount the new created jffs2 and unmount it, nothing is lost.
>> If i mount it, open a file, append some text, close it and unmount, 
>> then at the next mount everything is disapperaed (checking mtd2, all 
>> is set to 0xff).
>>
>> Saving modified files i notice a warning:
>> Writing files is also notice some MTD debug trace, maybe an error:
>> Node totlen on flash (0xffffffff) != totlen from node ref (0x00000074)
>
> Out of curiosity, what exactly is the type of flash you are using?
>
> /Ricard

Hi Ricard,

thanks again for help

the flash chip is an SST 39VF2301B, word programmable, tot 4MB, 4KB 
sector size, 64K block size, it is very similar to an AMD 16bit data bus 
width flash.

It seems to be correctly detected from jedec probe, but through CFI 
queries probably

...
physmap platform flash device: 00400000 at ffc00000
physmap-flash: Found 1 x16 devices at 0x0 in 16-bit bank. Manufacturer 
ID 0x0000bf Chip ID 0x00235d
number of CFI chips: 1
...

/proc # cat /proc/mtd
dev:    size   erasesize  name
mtd0: 00010000 00001000 "Colilo (64K)"
mtd1: 002f0000 00001000 "Kernel+ROMfs (3008K)"
mtd2: 00100000 00001000 "JFFS2 (1024K)"
mtd3: 0009d000 00001000 "ROMfs"

This is a suspected sequence of MTD commands i find in dmesg:

...
MTD_ioctl
MTD_ioctl
MTD_ioctl
MTD_ioctl
MTD_ioctl
MTD_ioctl
MTD_close
MTD_open
MTD_write
MTD_close
Node totlen on flash (0xffffffff) != totlen from node ref (0x00000074)
MTD_open <-- jffs2 fs disapperaed from here
MTD_read
MTD_read
...

many thanks,
angelo