Re: Mounting IRIX filesystem with version 1 directories?

[Toralf Lund <toralf@kscanners.com>]

On 01/02 2002 13:33 Stephen Lord wrote:
> Toralf Lund wrote:
> 
>> From the XFS FAQ,
>> 
>> Will I be able to use my old IRIX XFS disks on linux?
>> 
>> [ ... ] Linux can only read v2 directories on the moment. Using v1 will 
>> probably fail in spectacular ways.
>> 
>> I have a large IRIX filesystem that I would like to mount on Linux, but 
>> I think it has version 1 directories. Is there any way at all I can get 
>> this to work?
>> 
> First of all, your Irix filesystem is going to have to meet a few other 
> requirements :
> 
>  o It cannot be xlv or xvm based - there is no linux support for these
>  o the filesystem blocksize needs to be the same as the page size on 
> your linux block,
>     the irix default is 4K, so this is usually not a problem
>  o it should not have the unwritten extent support turned on.
> 
I know, but as far as I can tell, all those requirements are met. I wasn't 
able to mount the file system on a Red Hat 7.2 box with 
kernel-2.4.9-13SGI_XFS_1.0.2, though. I didn't have the opportunity to 
experiment a lot, though, as someone needed the data pretty fast (the file 
system in question had to be moved from an Origin server due to SCSI 
problems. Ideally, I wanted to put it on a Linux hosts, but it ended up on 
an O2 workstation, at least temporarily.) Are the precompiled kernels 
supposed to support everything needed?

> You can check the latter 2 with xfs_growfs -n /mnt on irix
That one's new to me. I used xfs_db to check...

> 
> The directory code should work for the most part, but large directories 
> may suffer
> problems with readdir on linux - the V1 format passes up 64 bit hash 
> values as
> directory offsets, and this confuses glibc from time to time. Entries 
> can go
> missing or you can occassionally get into a loop.
Is there any way to convert the existing directories, or at least mix 
version 1 and 2?

- Toralf