xfs - fixing wrong xfs size

[Eric Sandeen]

Nebojsa Trpkovic wrote:
> hello.
> 
> I had problem with raid5 on my system.
> after recovering of the array, I can not mount XFS that resides on it.
> I've run xfs_check and xfs_repair (which fixed some errors) and now I
> can run them all day long without any errors.
> 
> but, when I try to mount that partition, I get:
> 
> mount: /dev/md0: can't read superblock
> 
> 
> and there's
> 
> Filesystem "md0": Disabling barriers, not supported by the underlying device
> 
> attempt to access beyond end of device
> md0: rw=0, want=123024384, limit=123023488
> I/O error in filesystem ("md0") meta-data dev md0 block 0x75533f8

       ("xfs_read_buf") error 5 buf count 4096
> 
> XFS: size check 2 failed

So, the superblock says that the fs is 896 1k-blocks longer than the
device actually is.

> in the dmesg.
> 
> 
> is there any way to "fix" this wrong size of XFS ?

hard to say, almost certainly sounds like an md problem; is there a
chance that your raid recovery led to a device which is somehow smaller
than it started?  You could change the superblock block-count value, but
I'm guessing that something else has gone wrong.

It might be useful to know what errors xfs_repair found.

-Eric