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>
diff --git a/fs/xfs/libxfs/xfs_trans_space.h b/fs/xfs/libxfs/xfs_trans_space.h
index 41e0428..7917f6e 100644
--- a/fs/xfs/libxfs/xfs_trans_space.h
+++ b/fs/xfs/libxfs/xfs_trans_space.h
@@ -21,6 +21,8 @@
/*
* Components of space reservations.
*/
+#define XFS_MAX_CONTIG_RMAPS_PER_BLOCK(mp) \
+ (((mp)->m_rmap_mxr[0]) - ((mp)->m_rmap_mnr[0]))
#define XFS_MAX_CONTIG_EXTENTS_PER_BLOCK(mp) \
(((mp)->m_alloc_mxr[0]) - ((mp)->m_alloc_mnr[0]))
#define XFS_EXTENTADD_SPACE_RES(mp,w) (XFS_BM_MAXLEVELS(mp,w) - 1)
@@ -28,6 +30,13 @@
(((b + XFS_MAX_CONTIG_EXTENTS_PER_BLOCK(mp) - 1) / \
XFS_MAX_CONTIG_EXTENTS_PER_BLOCK(mp)) * \
XFS_EXTENTADD_SPACE_RES(mp,w))
+#define XFS_SWAP_RMAP_SPACE_RES(mp,b,w)\
+ (((b + XFS_MAX_CONTIG_EXTENTS_PER_BLOCK(mp) - 1) / \
+ XFS_MAX_CONTIG_EXTENTS_PER_BLOCK(mp)) * \
+ XFS_EXTENTADD_SPACE_RES(mp,w) + \
+ ((b + XFS_MAX_CONTIG_RMAPS_PER_BLOCK(mp) - 1) / \
+ XFS_MAX_CONTIG_RMAPS_PER_BLOCK(mp)) * \
+ (mp)->m_rmap_maxlevels)
#define XFS_DAENTER_1B(mp,w) \
((w) == XFS_DATA_FORK ? (mp)->m_dir_geo->fsbcount : 1)
#define XFS_DAENTER_DBS(mp,w) \