[PATCH v7 00/47] xfs: add reverse mapping support

[Artem Bityutskiy]

On Fri, 2016-08-05 at 09:50 +1000, Dave Chinner wrote:
> I'd much prefer that fiemap gives exact information about shared
> extents. FIEMAP is a diagnostic tool and as such we need it to
> accurately reflect the exact extent map of the inode being queried
> so we aren't mislead about the layout of the file during trouble
> shooting.

Hi Dave, you are right, and here is a side note:  we were using FIEMAP
for optimizing image deployment in production, so it is a diagnostic
tool and more.