From: Darrick J. Wong Date: Thu, 11 May 2017 19:01:09 +0000 (-0500) Subject: xfs: reserve enough blocks to handle btree splits when remapping X-Git-Tag: v4.12.0-rc1~33 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=4726325d8f8824473296adf3df53d0046e211c9b;p=thirdparty%2Fxfsprogs-dev.git xfs: reserve enough blocks to handle btree splits when remapping Source kernel commit: fe0be23e68200573de027de9b8cc2b27e7fce35e In xfs_reflink_end_cow, we erroneously reserve only enough blocks to handle adding 1 extent. This is problematic if we fragment free space, have to do CoW, and then have to perform multiple bmap btree expansions. Furthermore, the BUI recovery routine doesn't reserve /any/ blocks to handle btree splits, so log recovery fails after our first error causes the filesystem to go down. Therefore, refactor the transaction block reservation macros until we have a macro that works for our deferred (re)mapping activities, and fix both problems by using that macro. With 1k blocks we can hit this fairly often in g/187 if the scratch fs is big enough. Signed-off-by: Darrick J. Wong Reviewed-by: Christoph Hellwig Signed-off-by: Eric Sandeen --- diff --git a/libxfs/xfs_trans_space.h b/libxfs/xfs_trans_space.h index 7917f6e44..d787c677d 100644 --- a/libxfs/xfs_trans_space.h +++ b/libxfs/xfs_trans_space.h @@ -21,8 +21,20 @@ /* * Components of space reservations. */ + +/* Worst case number of rmaps that can be held in a block. */ #define XFS_MAX_CONTIG_RMAPS_PER_BLOCK(mp) \ (((mp)->m_rmap_mxr[0]) - ((mp)->m_rmap_mnr[0])) + +/* Adding one rmap could split every level up to the top of the tree. */ +#define XFS_RMAPADD_SPACE_RES(mp) ((mp)->m_rmap_maxlevels) + +/* Blocks we might need to add "b" rmaps to a tree. */ +#define XFS_NRMAPADD_SPACE_RES(mp, b)\ + (((b + XFS_MAX_CONTIG_RMAPS_PER_BLOCK(mp) - 1) / \ + XFS_MAX_CONTIG_RMAPS_PER_BLOCK(mp)) * \ + XFS_RMAPADD_SPACE_RES(mp)) + #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) @@ -30,13 +42,12 @@ (((b + XFS_MAX_CONTIG_EXTENTS_PER_BLOCK(mp) - 1) / \ XFS_MAX_CONTIG_EXTENTS_PER_BLOCK(mp)) * \ XFS_EXTENTADD_SPACE_RES(mp,w)) + +/* Blocks we might need to add "b" mappings & rmappings to a file. */ #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) + (XFS_NEXTENTADD_SPACE_RES((mp), (b), (w)) + \ + XFS_NRMAPADD_SPACE_RES((mp), (b))) + #define XFS_DAENTER_1B(mp,w) \ ((w) == XFS_DATA_FORK ? (mp)->m_dir_geo->fsbcount : 1) #define XFS_DAENTER_DBS(mp,w) \