Can't find correct configuration

Wed Sep 6 04:30:57 PDT 2023

在 2023/9/6 17:21, Leon Pollak 写道:
> Zhihao Cheng, please, excuse my stupidity...:-)
> To utilize these 8MiB I set "-c 2047".
> I thought that 248MiB/126976=2048 and -1 to be on the safe side.
> But I do not see any change in the kernel log.
> Should I also change the ubifs.cfg file and increase the vol_size?
> 

The 8M partition is used for uboot, and the 248M partition is used for 
UBI, isn't it? The 8M partition won't be used for UBI.

Current '-c 1981' can make sure that UBIFS take max space of ubi_rootfs 
volume.

> On Wed, 6 Sept 2023 at 11:53, Zhihao Cheng <chengzhihao1 at huawei.com> wrote:
>>
>> 在 2023/9/6 16:38, Leon Pollak 写道:
>>> Yes, you are right about the situation.
>>> My partition for UBI is 248MiB.
>>> So, the question remains - can this 8MB be utilized?
>>
>> Yes, it can.
>>
>>> Or are they already in use by UBI which sees partition size?
>>>
>>>
>>> On Wed, 6 Sept 2023 at 10:34, Zhihao Cheng <chengzhihao1 at huawei.com> wrote:
>>>>
>>>> 在 2023/9/6 15:27, Leon Pollak 写道:
>>>>> I work on embedded device. The rest of the NAND is used for SPL,
>>>>> U-Boot, U-Boot environment and kernel.
>>>>> What is left is 248MiB.
>>>>> I am not sure I can use the whole space for UBI - how will the SPL/U-Boot work?
>>>>
>>>> Do you mean UBI and uboot are put into same flash(256M)? If so, your
>>>> partitioning method is right.
>>>>
>>>> 8M(mtd0) - uboot
>>>> 248M(mtd1) - UBI
>>>>
>>>> UBI won't access mtd0.
>>>>
>>>>
>>>>>
>>>>> On Wed, 6 Sept 2023 at 10:21, Zhihao Cheng <chengzhihao1 at huawei.com> wrote:
>>>>>>
>>>>>> 在 2023/9/6 14:57, Leon Pollak 写道:
>>>>>>> Thousands of thanks, Zhihao Cheng!!!
>>>>>>> It worked exactly as you wrote.
>>>>>>> The only question remained is:
>>>>>>> My partition size is 248MiB.
>>>>>>> I thought that leaving 8MiB "spare' will be used just for these
>>>>>>> reserved PEBs, but now I understand this was incorrect.
>>>>>>> So, may I utilize these 8MiB back or will they still be used by UBI
>>>>>>> for something?
>>>>>>>
>>>>>>
>>>>>> I believe you have two mtd devices, 248M(mtd0 for ubi) and 8M(reserved,
>>>>>> won't be accessed by UBI) now. Please don't split the 256M into two mtd
>>>>>> devices if you only need 1 UBI device, just format the whole flash(256M)
>>>>>> into UBI, and UBI itself will handle its reservation without user
>>>>>> intervening.
>>>>>>
>>>>>>> On Wed, 6 Sept 2023 at 05:50, Zhihao Cheng <chengzhihao1 at huawei.com> wrote:
>>>>>>>>
>>>>>>>> 在 2023/9/6 10:42, Zhihao Cheng 写道:
>>>>>>>>> 在 2023/9/5 22:45, Leon Pollak 写道:
>>>>>>>>> Hi
>>>>>>>>>> Hello, all.
>>>>>>>>>> I will be very very thankful for the help to find the correct
>>>>>>>>>> configuration for my NAND.
>>>>>>>>>> I passed through a lot of mails in the lists and google and ChatGPT -
>>>>>>>>>> no success.
>>>>>>>>>> I have 256MB NAND and 248MB partition for UBIFS. I run:
>>>>>>>>>> mkfs.ubifs -v -r rootfs -F -m 2048 -e 126976 -c 1981 -o ./ubifs.img
>>>>>>>>>> ubinize -v -o rootfs.img -m 2048 -p 128KiB -s 512 -O 2048 ubinize.cfg
>>>>>>>>>> -----
>>>>>>>>>> and ubinize.cfg looks like:
>>>>>>>>>> [ubifs]
>>>>>>>>>> mode=ubi
>>>>>>>>>> image=./ubifs.img
>>>>>>>>>> vol_id=0
>>>>>>>>>> vol_size=240MiB
>>>>>>>>>> vol_type=dynamic
>>>>>>>>>> vol_name=ubi_rootfs
>>>>>>>>>> vol_alignment=1
>>>>>>>>>> vol_flags=autoresize
>>>>>>>>>> ------
>>>>>>>>>> Kernel configuration  was with CONFIG_MTD_UBI_BEB_LIMIT=20.
>>>>>>>>>> and here is the kernel log:
>>>>>>>>>> [    2.695659] ubi0: attaching mtd4
>>>>>>>>>> [    3.372343] ubi0: scanning is finished
>>>>>>>>>> [    3.383066] ubi0 warning: ubi_eba_init: cannot reserve enough PEBs
>>>>>>>>>> for bad PEB handling, reserved 4, need 40
>>>>>>>>>> [    3.404320] ubi0: volume 0 ("ubi_rootfs") re-sized from 1982 to
>>>>>>>>>> 1982 LEBs
>>>>>>>>>> [    3.411667] ubi0: attached mtd4 (name "FS", size 248 MiB)
>>>>>>>>>> [    3.417095] ubi0: PEB size: 131072 bytes (128 KiB), LEB size:
>>>>>>>>>> 126976 bytes
>>>>>>>>>> [    3.424006] ubi0: min./max. I/O unit sizes: 2048/2048, sub-page
>>>>>>>>>> size 512
>>>>>>>>>> [    3.430740] ubi0: VID header offset: 2048 (aligned 2048), data
>>>>>>>>>> offset: 4096
>>>>>>>>>> [    3.437734] ubi0: good PEBs: 1990, bad PEBs: 0, corrupted PEBs: 0
>>>>>>>>>> [    3.443860] ubi0: user volume: 1, internal volumes: 1, max. volumes
>>>>>>>>>> count: 128
>>>>>>>>>> [    3.451117] ubi0: max/mean erase counter: 1/0, WL threshold: 4096,
>>>>>>>>>> image sequence number: 1590570073
>>>>>>>>>> [    3.460295] ubi0: available PEBs: 0, total reserved PEBs: 1990,
>>>>>>>>>> PEBs reserved for bad PEB handling: 4
>>>>>>>>>> [    3.469575] ubi0: background thread "ubi_bgt0d" started, PID 131
>>>>>>>>>> [    4.648718] UBIFS (ubi0:0): background thread "ubifs_bgt0_0"
>>>>>>>>>> started, PID 136
>>>>>>>>>> [    4.676640] UBIFS (ubi0:0): start fixing up free space
>>>>>>>>>> [   10.250099] UBIFS (ubi0:0): free space fixup complete
>>>>>>>>>> [   10.269046] UBIFS (ubi0:0): UBIFS: mounted UBI device 0, volume 0,
>>>>>>>>>> name "ubi_rootfs"
>>>>>>>>>> [   10.276830] UBIFS (ubi0:0): LEB size: 126976 bytes (124 KiB),
>>>>>>>>>> min./max. I/O unit sizes: 2048 bytes/2048 bytes
>>>>>>>>>> [   10.286794] UBIFS (ubi0:0): FS size: 250142720 bytes (238 MiB, 1970
>>>>>>>>>> LEBs), journal size 9023488 bytes (8 MiB, 72 LEBs)
>>>>>>>>>> [   10.297540] UBIFS (ubi0:0): reserved for root: 0 bytes (0 KiB)
>>>>>>>>>> [   10.303406] UBIFS (ubi0:0): media format: w4/r0 (latest is w5/r0),
>>>>>>>>>> UUID A14D586A-32E2-45D7-A07E-BDC472FDF31D, small LPT model
>>>>>>>>>>
>>>>>>>>>> My question is: why does this warning about reserved 4, needed 40
>>>>>>>>>> appear? How can I solve this?
>>>>>>>>>>
>>>>>>>>>
>>>>>>>>> Solution: Modify ubinize.cfg,  vol_size=240MiB -> vol_size=235MiB
>>>>>>>>>
>>>>>>>>> Why does this warning about reserved 4, needed 40 appear?
>>>>>>>>> The count of bad PEBs reserved by UBI is: total_pebs(nand chip) *
>>>>>>>>> CONFIG_MTD_UBI_BEB_LIMIT/1024 = 2048 *  20 / 1024 = 40
>>>>>>>>> When fastmap is not enabled, the count of internal PEBs reserved by UBI
>>>>>>>>> is: UBI_LAYOUT_VOLUME_EBS[2] + WL_RESERVED_PEBS[1] +
>>>>>>>>> EBA_RESERVED_PEBS[1] = 4
>>>>>>>>>
>>>>>>>>> Total PEBs for UBI is 1990(good PEBs: 1990), the max count of user
>>>>>>>>> volume PEBs is 1990 - 40 - 4 = 1946
>>>>>>>>>
>>>>>>>>> In ubinize.cfg, vol_size=240MiB, the count of user volume PEBs is(see
>>>>>>>>> ubinize.c in mtduitls): vi_size + (leb_size - 1) / leb_size
>>>>>>>>> vi_size = 240M = 240 * 1024 * 1024
>>>>>>>>> leb_size = 128K - 2K(ec) - 2K(vid) = 124 * 1024
>>>>>>>>> result = 1982
>>>>>>>>>
>>>>>>>>> So there are 1990 - 1982 - 4 = 4 PEBs reserved for bad PEB handling,
>>>>>>>>> which is less than 40.
>>>>>>>>>
>>>>>>>>> When we set  vol_size=235MiB, the count of user volume PEBs is: (235 *
>>>>>>>>> 1024 * 1024 + 124 * 1024 - 1) / (124 * 1024) = 1941
>>>>>>>>> 1990 - 4 - 40 = 1946, finally maybe there is message from kernel like
>>>>>>>>> "("ubi_rootfs") re-sized from 1941 to 1946 LEBs".
>>>>>>>>
>>>>>>>> Acutally, the 'vol_size' in ubinize.cfg means the size of data on
>>>>>>>> volume(exclude vid/ec), not the size of volume(include vid/ec).
>>>>>>>>
>>>>>>>
>>>>>>> .
>>>>>>>
>>>>>>
>>>>>
>>>>> .
>>>>>
>>>>
>>>
>>> .
>>>
>>
> 
> .
> 