Re: [PATCH 1/2] xfs: force writes to delalloc regions to unwritten

Christoph Hellwig
2020-01-16T16:47:45Z

On Wed, Jan 15, 2020 at 10:15:50PM -0800, Darrick J. Wong wrote:
> From: Darrick J. Wong <darrick.wong@oracle.com>
>
> When writing to a delalloc region in the data fork, commit the new
> allocations (of the da reservation) as unwritten so that the mappings
> are only marked written once writeback completes successfully. This
> fixes the problem of stale data exposure if the system goes down during
> targeted writeback of a specific region of a file, as tested by
> generic/042.

I think this is the only safe way to deal with buffered I/O into
holes, so:

Reviewed-by: Christoph Hellwig <hch@lst.de>