Re: [f2fs-dev] Multidevice f2fs mount after disk rearrangement
From: Chao Yu
Date: Sun Jan 05 2020 - 22:41:12 EST
Thanks for the report. :)
On 2020/1/5 5:52, Oleksandr Natalenko via Linux-f2fs-devel wrote:
> On 04.01.2020 17:29, Oleksandr Natalenko wrote:
>> I was brave enough to create f2fs filesystem spanning through 2
>> physical device using this command:
>> # mkfs.f2fs -t 0 /dev/sdc -c /dev/sdd
>> It worked fine until I removed /dev/sdb from my system, so f2fs devices
>> /dev/sdc -> /dev/sdb
>> /dev/sdd -> /dev/sdc
>> Now, when I try to mount it, I get the following:
>> # mount -t f2fs /dev/sdb /mnt/fs
>> mount: /mnt/fs: mount(2) system call failed: No such file or directory.
>> In dmesg:
>> [Jan 4 17:25] F2FS-fs (sdb): Mount Device [ 0]: /dev/sdc,
>> 59063, 0 - 1cd6fff
>> [ +0,000024] F2FS-fs (sdb): Failed to find devices
>> fsck also fails with the following assertion:
>> [ASSERT] (init_sb_info: 908) !strcmp((char *)sb->devs[i].path, (char
>> Am I doing something obviously stupid, and the device path can be
>> (somehow) changed so that the mount succeeds, or this is unfixable,
>> and f2fs relies on persistent device naming?
>> Please suggest.
>> Thank you.
> Erm, fine. I studied f2fs-tools code a little bit and discovered that
> superblock indeed had /dev/sdX paths saved as strings. So I fired up
> hexedit and just changed the superblock directly on the first device,
> substituting sdc with sdb and sdd with sdc (I did it twice; I guess
> there are 2 copies of superblock), and after this the mount worked.
Alright, it works if superblock checksum feature is off...
> Am I really supposed to do this manually ;)?
We'd better add that ability in tune.f2fs. And I guess we need to let
kernel/fsck to notice that case, and give hint to run tune.f2fs to
reconfigure primary/secondary/... device paths.