Re: [patch 0/9] writeback data integrity and other fixes (take 3)

[Christoph Hellwig <hch@xxxxxxxxxxxxx>]

On Wed, Oct 29, 2008 at 02:16:45PM +1100, Dave Chinner wrote:
> Yeah, that'd do it. Good catch. I can't believe I recently fixed a
> bug that touched these lines of code without noticing the inversion.
> Sometimes I wonder if we should just conver the entire of XFS to
> return negative errors - mistakes in handling negative error numbers
> in the core XFS code happen all the time.
> 
> FWIW, the core issue here is that we've got to do the
> filemap_fdatawait() call in the ->fsync method because ->fsync
> gets called before we've waited for the data I/O to complete.
> XFS updates inode state on I/O completion, so we *must* wait
> for data I/O to complete before logging the inode changes. I
> think btrfs has the same problem....

Yes.  I have patches to fix this by changing what ->fsync does and
how it's called.  I really need to get them out on the list.