On Tue, Mar 19, 2013 at 09:23:35AM -0400, Brian Foster wrote:
> The mkfs code currently creates a single free space extent record
> for each of the bno and cnt btrees in each AG. The start block of
> the record is pushed forward on the AG that hosts an internal log.
> If the log happens to consume all available space in the AG, the
> start block becomes equal to sb->sb_agblocks and thus invalid.
> This causes xfs_repair to complain.
>
> For example, the following sequence:
>
> mkfs.xfs -d file,name=./fs.img,size=50g,agsize=16m
> xfs_repair ./fs.img
>
> ... produces the following xfs_repair output:
>
> Phase 1 - find and verify superblock...
> Phase 2 - using internal log
> - scan filesystem freespace and inode maps...
> invalid start block 4096 in record 0 of bno btree block 1600/1
> invalid start block 4096 in record 0 of cnt btree block 1600/2
> - found root inode chunk
> ...
>
> xfs_repair appears to correct the numrecs value such that subsequent
> checks are successful. The sequence above is pulled from xfstests
> test #250, which fails due to this behavior.
>
> Modify mkfs.xfs such that we check the block count value of the
> free space record for the log AG after the log is accounted for. If
> no space is left for the record, reset the record count to 0.
>
> Signed-off-by: Brian Foster <bfoster@xxxxxxxxxx>
> ---
>
> v2:
> - Drop the byte swap.
> - Add a comment.
> - Fix up the commit log description.
Looks good.
Reviewed-by: Dave Chinner <dchinner@xxxxxxxxxx>
--
Dave Chinner
david@xxxxxxxxxxxxx
|