tree ae46494e7e50277389871deba53fca10e98f4f97
parent 39aff5fdb91e8fee6a2c28910a263a5228619ba2
author Darrick J. Wong <darrick.wong@oracle.com> 1475511113 -0700
committer Darrick J. Wong <darrick.wong@oracle.com> 1475709992 -0700

xfs: implement swapext for rmap filesystems

Implement swapext for filesystems that have reverse mapping.  Back in
the reflink patches, we augmented the bmap code with a 'REMAP' flag
that updates only the bmbt and doesn't touch the allocator and
implemented log redo items for those two operations.  Now we can
rewrite extent swapping as a (looong) series of remap operations.

This is far less efficient than the fork swapping method implemented
in the past, so we only switch this on for rmap.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>