From 04f130605ff6fb01a93a0885607921df9c463eed Mon Sep 17 00:00:00 2001 From: "Darrick J. Wong" Date: Wed, 3 Aug 2016 12:19:53 +1000 Subject: [PATCH] xfs: don't update rmapbt when fixing agfl Allow a caller of xfs_alloc_fix_freelist to disable rmapbt updates when fixing the AG freelist. xfs_repair needs this during phase 5 to be able to adjust the freelist while it's reconstructing the rmap btree; the missing entries will be added back at the very end of phase 5 once the AGFL contents settle down. Signed-off-by: Darrick J. Wong Reviewed-by: Dave Chinner Signed-off-by: Dave Chinner --- fs/xfs/libxfs/xfs_alloc.c | 18 ++++++++++++++---- fs/xfs/libxfs/xfs_alloc.h | 3 +++ 2 files changed, 17 insertions(+), 4 deletions(-) diff --git a/fs/xfs/libxfs/xfs_alloc.c b/fs/xfs/libxfs/xfs_alloc.c index 73ab1ea1270d..a0dc2999778d 100644 --- a/fs/xfs/libxfs/xfs_alloc.c +++ b/fs/xfs/libxfs/xfs_alloc.c @@ -2090,9 +2090,21 @@ xfs_alloc_fix_freelist( * anything other than extra overhead when we need to put more blocks * back on the free list? Maybe we should only do this when space is * getting low or the AGFL is more than half full? + * + * The NOSHRINK flag prevents the AGFL from being shrunk if it's too + * big; the NORMAP flag prevents AGFL expand/shrink operations from + * updating the rmapbt. Both flags are used in xfs_repair while we're + * rebuilding the rmapbt, and neither are used by the kernel. They're + * both required to ensure that rmaps are correctly recorded for the + * regenerated AGFL, bnobt, and cntbt. See repair/phase5.c and + * repair/rmap.c in xfsprogs for details. */ - xfs_rmap_ag_owner(&targs.oinfo, XFS_RMAP_OWN_AG); - while (pag->pagf_flcount > need) { + memset(&targs, 0, sizeof(targs)); + if (flags & XFS_ALLOC_FLAG_NORMAP) + xfs_rmap_skip_owner_update(&targs.oinfo); + else + xfs_rmap_ag_owner(&targs.oinfo, XFS_RMAP_OWN_AG); + while (!(flags & XFS_ALLOC_FLAG_NOSHRINK) && pag->pagf_flcount > need) { struct xfs_buf *bp; error = xfs_alloc_get_freelist(tp, agbp, &bno, 0); @@ -2106,10 +2118,8 @@ xfs_alloc_fix_freelist( xfs_trans_binval(tp, bp); } - memset(&targs, 0, sizeof(targs)); targs.tp = tp; targs.mp = mp; - xfs_rmap_ag_owner(&targs.oinfo, XFS_RMAP_OWN_AG); targs.agbp = agbp; targs.agno = args->agno; targs.alignment = targs.minlen = targs.prod = targs.isfl = 1; diff --git a/fs/xfs/libxfs/xfs_alloc.h b/fs/xfs/libxfs/xfs_alloc.h index 360f9e425536..6fe2d6b7cfe9 100644 --- a/fs/xfs/libxfs/xfs_alloc.h +++ b/fs/xfs/libxfs/xfs_alloc.h @@ -54,6 +54,9 @@ typedef unsigned int xfs_alloctype_t; */ #define XFS_ALLOC_FLAG_TRYLOCK 0x00000001 /* use trylock for buffer locking */ #define XFS_ALLOC_FLAG_FREEING 0x00000002 /* indicate caller is freeing extents*/ +#define XFS_ALLOC_FLAG_NORMAP 0x00000004 /* don't modify the rmapbt */ +#define XFS_ALLOC_FLAG_NOSHRINK 0x00000008 /* don't shrink the freelist */ + /* * Argument structure for xfs_alloc routines. -- 2.20.1