Re: REVIEW: Fix for incore extent corruption.

[Eric Sandeen <sandeen@sandeen.net>]

Lachlan McIlroy wrote:
> Eric Sandeen wrote:
>> Lachlan McIlroy wrote:
>>> Russell, this fixes xfs_iext_irec_compact_full().  If we don't move
>>> all the records from the next page into the current page then we need
>>> to update the er_extoff of the modified page as we move the remaining
>>> extents up.  Would you mind giving it a go?
>>>
>>> --- a/fs/xfs/xfs_inode.c	2008-09-18 18:48:46.000000000 +1000
>>> +++ b/fs/xfs/xfs_inode.c	2008-09-18 18:57:18.000000000 +1000
>>> @@ -4623,6 +4623,7 @@ xfs_iext_irec_compact_full(
>>>  					(XFS_LINEAR_EXTS -
>>>  						erp_next->er_extcount) *
>>>  					sizeof(xfs_bmbt_rec_t));
>>> +				erp_next->er_extoff += ext_diff;
>>>  			}
>>>  		}
>> Lachlan, I concur.  I spent way too long last night looking at this and
>> arrived at the same conclusion about the root cause of the problem, but
>> didn't hae *quite* the right solution.  I blame it on 2am ;)  Your fix
>> looks right.
>>
>> (though I'd probably move the erp_next changes into the else clause? 
>> Otherwise you're changing it then freeing it.)
> I don't understand what you mean by that.  Could you elaborate?

Sorry I mis-read where the above hunk went... that makes sense as-is above.

For clarity having the erp_next->er_extoff and er_extcount adjustments
together *might* make sense but no big deal.

-Eric