Re: [PATCH 08/12] xfs_repair: rebuild inode btrees with bulk loader

From: "Darrick J. Wong" <darrick.wong@oracle.com>
To: Brian Foster <bfoster@redhat.com>
Cc: sandeen@sandeen.net, linux-xfs@vger.kernel.org
Subject: Re: [PATCH 08/12] xfs_repair: rebuild inode btrees with bulk loader
Date: Thu, 18 Jun 2020 11:33:15 -0700	[thread overview]
Message-ID: <20200618183315.GA11245@magnolia> (raw)
In-Reply-To: <20200618152411.GB32216@bfoster>

On Thu, Jun 18, 2020 at 11:24:11AM -0400, Brian Foster wrote:
> On Mon, Jun 01, 2020 at 09:27:44PM -0700, Darrick J. Wong wrote:
> > From: Darrick J. Wong <darrick.wong@oracle.com>
> > 
> > Use the btree bulk loading functions to rebuild the inode btrees
> > and drop the open-coded implementation.
> > 
> > Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
> > ---
> >  libxfs/libxfs_api_defs.h |    1 
> >  repair/agbtree.c         |  207 ++++++++++++++++++++
> >  repair/agbtree.h         |   13 +
> >  repair/phase5.c          |  488 +++-------------------------------------------
> >  4 files changed, 248 insertions(+), 461 deletions(-)
> > 
> > 
> ...
> > diff --git a/repair/agbtree.c b/repair/agbtree.c
> > index 3b8ab47c..e44475fc 100644
> > --- a/repair/agbtree.c
> > +++ b/repair/agbtree.c
> > @@ -308,3 +308,210 @@ _("Error %d while creating cntbt btree for AG %u.\n"), error, agno);
> >  	libxfs_btree_del_cursor(btr_bno->cur, 0);
> >  	libxfs_btree_del_cursor(btr_cnt->cur, 0);
> >  }
> ...
> > +/* Initialize both inode btree cursors as needed. */
> > +void
> > +init_ino_cursors(
> > +	struct repair_ctx	*sc,
> > +	xfs_agnumber_t		agno,
> > +	unsigned int		free_space,
> > +	uint64_t		*num_inos,
> > +	uint64_t		*num_free_inos,
> > +	struct bt_rebuild	*btr_ino,
> > +	struct bt_rebuild	*btr_fino)
> > +{
> > +	struct ino_tree_node	*ino_rec;
> > +	unsigned int		ino_recs = 0;
> > +	unsigned int		fino_recs = 0;
> > +	bool			finobt;
> > +	int			error;
> > +
> > +	finobt = xfs_sb_version_hasfinobt(&sc->mp->m_sb);
> 
> Seems like a pointless variable given it is only used in one place.
> Otherwise looks good:

Fixed.

--D

> Reviewed-by: Brian Foster <bfoster@redhat.com>
> 
> > +	init_rebuild(sc, &XFS_RMAP_OINFO_INOBT, free_space, btr_ino);
> > +
> > +	/* Compute inode statistics. */
> > +	*num_free_inos = 0;
> > +	*num_inos = 0;
> > +	for (ino_rec = findfirst_inode_rec(agno);
> > +	     ino_rec != NULL;
> > +	     ino_rec = next_ino_rec(ino_rec))  {
> > +		unsigned int	rec_ninos = 0;
> > +		unsigned int	rec_nfinos = 0;
> > +		int		i;
> > +
> > +		for (i = 0; i < XFS_INODES_PER_CHUNK; i++)  {
> > +			ASSERT(is_inode_confirmed(ino_rec, i));
> > +			/*
> > +			 * sparse inodes are not factored into superblock (free)
> > +			 * inode counts
> > +			 */
> > +			if (is_inode_sparse(ino_rec, i))
> > +				continue;
> > +			if (is_inode_free(ino_rec, i))
> > +				rec_nfinos++;
> > +			rec_ninos++;
> > +		}
> > +
> > +		*num_free_inos += rec_nfinos;
> > +		*num_inos += rec_ninos;
> > +		ino_recs++;
> > +
> > +		/* finobt only considers records with free inodes */
> > +		if (rec_nfinos)
> > +			fino_recs++;
> > +	}
> > +
> > +	btr_ino->cur = libxfs_inobt_stage_cursor(sc->mp, &btr_ino->newbt.afake,
> > +			agno, XFS_BTNUM_INO);
> > +
> > +	btr_ino->bload.get_record = get_inobt_record;
> > +	btr_ino->bload.claim_block = rebuild_claim_block;
> > +	btr_ino->first_agino = NULLAGINO;
> > +
> > +	/* Compute how many inobt blocks we'll need. */
> > +	error = -libxfs_btree_bload_compute_geometry(btr_ino->cur,
> > +			&btr_ino->bload, ino_recs);
> > +	if (error)
> > +		do_error(
> > +_("Unable to compute inode btree geometry, error %d.\n"), error);
> > +
> > +	reserve_btblocks(sc->mp, agno, btr_ino, btr_ino->bload.nr_blocks);
> > +
> > +	if (!finobt)
> > +		return;
> > +
> > +	init_rebuild(sc, &XFS_RMAP_OINFO_INOBT, free_space, btr_fino);
> > +	btr_fino->cur = libxfs_inobt_stage_cursor(sc->mp,
> > +			&btr_fino->newbt.afake, agno, XFS_BTNUM_FINO);
> > +
> > +	btr_fino->bload.get_record = get_inobt_record;
> > +	btr_fino->bload.claim_block = rebuild_claim_block;
> > +	btr_fino->first_agino = NULLAGINO;
> > +
> > +	/* Compute how many finobt blocks we'll need. */
> > +	error = -libxfs_btree_bload_compute_geometry(btr_fino->cur,
> > +			&btr_fino->bload, fino_recs);
> > +	if (error)
> > +		do_error(
> > +_("Unable to compute free inode btree geometry, error %d.\n"), error);
> > +
> > +	reserve_btblocks(sc->mp, agno, btr_fino, btr_fino->bload.nr_blocks);
> > +}
> > +
> > +/* Rebuild the inode btrees. */
> > +void
> > +build_inode_btrees(
> > +	struct repair_ctx	*sc,
> > +	xfs_agnumber_t		agno,
> > +	struct bt_rebuild	*btr_ino,
> > +	struct bt_rebuild	*btr_fino)
> > +{
> > +	int			error;
> > +
> > +	/* Add all observed inobt records. */
> > +	error = -libxfs_btree_bload(btr_ino->cur, &btr_ino->bload, btr_ino);
> > +	if (error)
> > +		do_error(
> > +_("Error %d while creating inobt btree for AG %u.\n"), error, agno);
> > +
> > +	/* Since we're not writing the AGI yet, no need to commit the cursor */
> > +	libxfs_btree_del_cursor(btr_ino->cur, 0);
> > +
> > +	if (!xfs_sb_version_hasfinobt(&sc->mp->m_sb))
> > +		return;
> > +
> > +	/* Add all observed finobt records. */
> > +	error = -libxfs_btree_bload(btr_fino->cur, &btr_fino->bload, btr_fino);
> > +	if (error)
> > +		do_error(
> > +_("Error %d while creating finobt btree for AG %u.\n"), error, agno);
> > +
> > +	/* Since we're not writing the AGI yet, no need to commit the cursor */
> > +	libxfs_btree_del_cursor(btr_fino->cur, 0);
> > +}
> > diff --git a/repair/agbtree.h b/repair/agbtree.h
> > index 63352247..3cad2a8e 100644
> > --- a/repair/agbtree.h
> > +++ b/repair/agbtree.h
> > @@ -24,6 +24,12 @@ struct bt_rebuild {
> >  			struct extent_tree_node	*bno_rec;
> >  			unsigned int		freeblks;
> >  		};
> > +		struct {
> > +			struct ino_tree_node	*ino_rec;
> > +			xfs_agino_t		first_agino;
> > +			xfs_agino_t		count;
> > +			xfs_agino_t		freecount;
> > +		};
> >  	};
> >  };
> >  
> > @@ -36,4 +42,11 @@ void init_freespace_cursors(struct repair_ctx *sc, xfs_agnumber_t agno,
> >  void build_freespace_btrees(struct repair_ctx *sc, xfs_agnumber_t agno,
> >  		struct bt_rebuild *btr_bno, struct bt_rebuild *btr_cnt);
> >  
> > +void init_ino_cursors(struct repair_ctx *sc, xfs_agnumber_t agno,
> > +		unsigned int free_space, uint64_t *num_inos,
> > +		uint64_t *num_free_inos, struct bt_rebuild *btr_ino,
> > +		struct bt_rebuild *btr_fino);
> > +void build_inode_btrees(struct repair_ctx *sc, xfs_agnumber_t agno,
> > +		struct bt_rebuild *btr_ino, struct bt_rebuild *btr_fino);
> > +
> >  #endif /* __XFS_REPAIR_AG_BTREE_H__ */
> > diff --git a/repair/phase5.c b/repair/phase5.c
> > index a93d900d..e570349d 100644
> > --- a/repair/phase5.c
> > +++ b/repair/phase5.c
> > @@ -67,15 +67,6 @@ typedef struct bt_status  {
> >  	uint64_t		owner;		/* owner */
> >  } bt_status_t;
> >  
> > -/*
> > - * extra metadata for the agi
> > - */
> > -struct agi_stat {
> > -	xfs_agino_t		first_agino;
> > -	xfs_agino_t		count;
> > -	xfs_agino_t		freecount;
> > -};
> > -
> >  static uint64_t	*sb_icount_ag;		/* allocated inodes per ag */
> >  static uint64_t	*sb_ifree_ag;		/* free inodes per ag */
> >  static uint64_t	*sb_fdblocks_ag;	/* free data blocks per ag */
> > @@ -369,229 +360,20 @@ btnum_to_ops(
> >  	}
> >  }
> >  
> > -/*
> > - * XXX(hch): any reason we don't just look at mp->m_inobt_mxr?
> > - */
> > -#define XR_INOBT_BLOCK_MAXRECS(mp, level) \
> > -			libxfs_inobt_maxrecs((mp), (mp)->m_sb.sb_blocksize, \
> > -						(level) == 0)
> > -
> > -/*
> > - * we don't have to worry here about how chewing up free extents
> > - * may perturb things because inode tree building happens before
> > - * freespace tree building.
> > - */
> > -static void
> > -init_ino_cursor(xfs_mount_t *mp, xfs_agnumber_t agno, bt_status_t *btree_curs,
> > -		uint64_t *num_inos, uint64_t *num_free_inos, int finobt)
> > -{
> > -	uint64_t		ninos;
> > -	uint64_t		nfinos;
> > -	int			rec_nfinos;
> > -	int			rec_ninos;
> > -	ino_tree_node_t		*ino_rec;
> > -	int			num_recs;
> > -	int			level;
> > -	bt_stat_level_t		*lptr;
> > -	bt_stat_level_t		*p_lptr;
> > -	xfs_extlen_t		blocks_allocated;
> > -	int			i;
> > -
> > -	*num_inos = *num_free_inos = 0;
> > -	ninos = nfinos = 0;
> > -
> > -	lptr = &btree_curs->level[0];
> > -	btree_curs->init = 1;
> > -	btree_curs->owner = XFS_RMAP_OWN_INOBT;
> > -
> > -	/*
> > -	 * build up statistics
> > -	 */
> > -	ino_rec = findfirst_inode_rec(agno);
> > -	for (num_recs = 0; ino_rec != NULL; ino_rec = next_ino_rec(ino_rec))  {
> > -		rec_ninos = 0;
> > -		rec_nfinos = 0;
> > -		for (i = 0; i < XFS_INODES_PER_CHUNK; i++)  {
> > -			ASSERT(is_inode_confirmed(ino_rec, i));
> > -			/*
> > -			 * sparse inodes are not factored into superblock (free)
> > -			 * inode counts
> > -			 */
> > -			if (is_inode_sparse(ino_rec, i))
> > -				continue;
> > -			if (is_inode_free(ino_rec, i))
> > -				rec_nfinos++;
> > -			rec_ninos++;
> > -		}
> > -
> > -		/*
> > -		 * finobt only considers records with free inodes
> > -		 */
> > -		if (finobt && !rec_nfinos)
> > -			continue;
> > -
> > -		nfinos += rec_nfinos;
> > -		ninos += rec_ninos;
> > -		num_recs++;
> > -	}
> > -
> > -	if (num_recs == 0) {
> > -		/*
> > -		 * easy corner-case -- no inode records
> > -		 */
> > -		lptr->num_blocks = 1;
> > -		lptr->modulo = 0;
> > -		lptr->num_recs_pb = 0;
> > -		lptr->num_recs_tot = 0;
> > -
> > -		btree_curs->num_levels = 1;
> > -		btree_curs->num_tot_blocks = btree_curs->num_free_blocks = 1;
> > -
> > -		setup_cursor(mp, agno, btree_curs);
> > -
> > -		return;
> > -	}
> > -
> > -	blocks_allocated = lptr->num_blocks = howmany(num_recs,
> > -					XR_INOBT_BLOCK_MAXRECS(mp, 0));
> > -
> > -	lptr->modulo = num_recs % lptr->num_blocks;
> > -	lptr->num_recs_pb = num_recs / lptr->num_blocks;
> > -	lptr->num_recs_tot = num_recs;
> > -	level = 1;
> > -
> > -	if (lptr->num_blocks > 1)  {
> > -		for (; btree_curs->level[level-1].num_blocks > 1
> > -				&& level < XFS_BTREE_MAXLEVELS;
> > -				level++)  {
> > -			lptr = &btree_curs->level[level];
> > -			p_lptr = &btree_curs->level[level - 1];
> > -			lptr->num_blocks = howmany(p_lptr->num_blocks,
> > -				XR_INOBT_BLOCK_MAXRECS(mp, level));
> > -			lptr->modulo = p_lptr->num_blocks % lptr->num_blocks;
> > -			lptr->num_recs_pb = p_lptr->num_blocks
> > -					/ lptr->num_blocks;
> > -			lptr->num_recs_tot = p_lptr->num_blocks;
> > -
> > -			blocks_allocated += lptr->num_blocks;
> > -		}
> > -	}
> > -	ASSERT(lptr->num_blocks == 1);
> > -	btree_curs->num_levels = level;
> > -
> > -	btree_curs->num_tot_blocks = btree_curs->num_free_blocks
> > -			= blocks_allocated;
> > -
> > -	setup_cursor(mp, agno, btree_curs);
> > -
> > -	*num_inos = ninos;
> > -	*num_free_inos = nfinos;
> > -
> > -	return;
> > -}
> > -
> > -static void
> > -prop_ino_cursor(xfs_mount_t *mp, xfs_agnumber_t agno, bt_status_t *btree_curs,
> > -	xfs_btnum_t btnum, xfs_agino_t startino, int level)
> > -{
> > -	struct xfs_btree_block	*bt_hdr;
> > -	xfs_inobt_key_t		*bt_key;
> > -	xfs_inobt_ptr_t		*bt_ptr;
> > -	xfs_agblock_t		agbno;
> > -	bt_stat_level_t		*lptr;
> > -	const struct xfs_buf_ops *ops = btnum_to_ops(btnum);
> > -	int			error;
> > -
> > -	level++;
> > -
> > -	if (level >= btree_curs->num_levels)
> > -		return;
> > -
> > -	lptr = &btree_curs->level[level];
> > -	bt_hdr = XFS_BUF_TO_BLOCK(lptr->buf_p);
> > -
> > -	if (be16_to_cpu(bt_hdr->bb_numrecs) == 0)  {
> > -		/*
> > -		 * this only happens once to initialize the
> > -		 * first path up the left side of the tree
> > -		 * where the agbno's are already set up
> > -		 */
> > -		prop_ino_cursor(mp, agno, btree_curs, btnum, startino, level);
> > -	}
> > -
> > -	if (be16_to_cpu(bt_hdr->bb_numrecs) ==
> > -				lptr->num_recs_pb + (lptr->modulo > 0))  {
> > -		/*
> > -		 * write out current prev block, grab us a new block,
> > -		 * and set the rightsib pointer of current block
> > -		 */
> > -#ifdef XR_BLD_INO_TRACE
> > -		fprintf(stderr, " ino prop agbno %d ", lptr->prev_agbno);
> > -#endif
> > -		if (lptr->prev_agbno != NULLAGBLOCK)  {
> > -			ASSERT(lptr->prev_buf_p != NULL);
> > -			libxfs_buf_mark_dirty(lptr->prev_buf_p);
> > -			libxfs_buf_relse(lptr->prev_buf_p);
> > -		}
> > -		lptr->prev_agbno = lptr->agbno;;
> > -		lptr->prev_buf_p = lptr->buf_p;
> > -		agbno = get_next_blockaddr(agno, level, btree_curs);
> > -
> > -		bt_hdr->bb_u.s.bb_rightsib = cpu_to_be32(agbno);
> > -
> > -		error = -libxfs_buf_get(mp->m_dev,
> > -				XFS_AGB_TO_DADDR(mp, agno, agbno),
> > -				XFS_FSB_TO_BB(mp, 1), &lptr->buf_p);
> > -		if (error)
> > -			do_error(_("Cannot grab inode btree buffer, err=%d"),
> > -					error);
> > -		lptr->agbno = agbno;
> > -
> > -		if (lptr->modulo)
> > -			lptr->modulo--;
> > -
> > -		/*
> > -		 * initialize block header
> > -		 */
> > -		lptr->buf_p->b_ops = ops;
> > -		bt_hdr = XFS_BUF_TO_BLOCK(lptr->buf_p);
> > -		memset(bt_hdr, 0, mp->m_sb.sb_blocksize);
> > -		libxfs_btree_init_block(mp, lptr->buf_p, btnum,
> > -					level, 0, agno);
> > -
> > -		bt_hdr->bb_u.s.bb_leftsib = cpu_to_be32(lptr->prev_agbno);
> > -
> > -		/*
> > -		 * propagate extent record for first extent in new block up
> > -		 */
> > -		prop_ino_cursor(mp, agno, btree_curs, btnum, startino, level);
> > -	}
> > -	/*
> > -	 * add inode info to current block
> > -	 */
> > -	be16_add_cpu(&bt_hdr->bb_numrecs, 1);
> > -
> > -	bt_key = XFS_INOBT_KEY_ADDR(mp, bt_hdr,
> > -				    be16_to_cpu(bt_hdr->bb_numrecs));
> > -	bt_ptr = XFS_INOBT_PTR_ADDR(mp, bt_hdr,
> > -				    be16_to_cpu(bt_hdr->bb_numrecs),
> > -				    M_IGEO(mp)->inobt_mxr[1]);
> > -
> > -	bt_key->ir_startino = cpu_to_be32(startino);
> > -	*bt_ptr = cpu_to_be32(btree_curs->level[level-1].agbno);
> > -}
> > -
> >  /*
> >   * XXX: yet more code that can be shared with mkfs, growfs.
> >   */
> >  static void
> > -build_agi(xfs_mount_t *mp, xfs_agnumber_t agno, bt_status_t *btree_curs,
> > -		bt_status_t *finobt_curs, struct agi_stat *agi_stat)
> > +build_agi(
> > +	struct xfs_mount	*mp,
> > +	xfs_agnumber_t		agno,
> > +	struct bt_rebuild	*btr_ino,
> > +	struct bt_rebuild	*btr_fino)
> >  {
> > -	xfs_buf_t	*agi_buf;
> > -	xfs_agi_t	*agi;
> > -	int		i;
> > -	int		error;
> > +	struct xfs_buf		*agi_buf;
> > +	struct xfs_agi		*agi;
> > +	int			i;
> > +	int			error;
> >  
> >  	error = -libxfs_buf_get(mp->m_dev,
> >  			XFS_AG_DADDR(mp, agno, XFS_AGI_DADDR(mp)),
> > @@ -611,11 +393,11 @@ build_agi(xfs_mount_t *mp, xfs_agnumber_t agno, bt_status_t *btree_curs,
> >  	else
> >  		agi->agi_length = cpu_to_be32(mp->m_sb.sb_dblocks -
> >  			(xfs_rfsblock_t) mp->m_sb.sb_agblocks * agno);
> > -	agi->agi_count = cpu_to_be32(agi_stat->count);
> > -	agi->agi_root = cpu_to_be32(btree_curs->root);
> > -	agi->agi_level = cpu_to_be32(btree_curs->num_levels);
> > -	agi->agi_freecount = cpu_to_be32(agi_stat->freecount);
> > -	agi->agi_newino = cpu_to_be32(agi_stat->first_agino);
> > +	agi->agi_count = cpu_to_be32(btr_ino->count);
> > +	agi->agi_root = cpu_to_be32(btr_ino->newbt.afake.af_root);
> > +	agi->agi_level = cpu_to_be32(btr_ino->newbt.afake.af_levels);
> > +	agi->agi_freecount = cpu_to_be32(btr_ino->freecount);
> > +	agi->agi_newino = cpu_to_be32(btr_ino->first_agino);
> >  	agi->agi_dirino = cpu_to_be32(NULLAGINO);
> >  
> >  	for (i = 0; i < XFS_AGI_UNLINKED_BUCKETS; i++)
> > @@ -625,203 +407,16 @@ build_agi(xfs_mount_t *mp, xfs_agnumber_t agno, bt_status_t *btree_curs,
> >  		platform_uuid_copy(&agi->agi_uuid, &mp->m_sb.sb_meta_uuid);
> >  
> >  	if (xfs_sb_version_hasfinobt(&mp->m_sb)) {
> > -		agi->agi_free_root = cpu_to_be32(finobt_curs->root);
> > -		agi->agi_free_level = cpu_to_be32(finobt_curs->num_levels);
> > +		agi->agi_free_root =
> > +				cpu_to_be32(btr_fino->newbt.afake.af_root);
> > +		agi->agi_free_level =
> > +				cpu_to_be32(btr_fino->newbt.afake.af_levels);
> >  	}
> >  
> >  	libxfs_buf_mark_dirty(agi_buf);
> >  	libxfs_buf_relse(agi_buf);
> >  }
> >  
> > -/*
> > - * rebuilds an inode tree given a cursor.  We're lazy here and call
> > - * the routine that builds the agi
> > - */
> > -static void
> > -build_ino_tree(xfs_mount_t *mp, xfs_agnumber_t agno,
> > -		bt_status_t *btree_curs, xfs_btnum_t btnum,
> > -		struct agi_stat *agi_stat)
> > -{
> > -	xfs_agnumber_t		i;
> > -	xfs_agblock_t		j;
> > -	xfs_agblock_t		agbno;
> > -	xfs_agino_t		first_agino;
> > -	struct xfs_btree_block	*bt_hdr;
> > -	xfs_inobt_rec_t		*bt_rec;
> > -	ino_tree_node_t		*ino_rec;
> > -	bt_stat_level_t		*lptr;
> > -	const struct xfs_buf_ops *ops = btnum_to_ops(btnum);
> > -	xfs_agino_t		count = 0;
> > -	xfs_agino_t		freecount = 0;
> > -	int			inocnt;
> > -	uint8_t			finocnt;
> > -	int			k;
> > -	int			level = btree_curs->num_levels;
> > -	int			spmask;
> > -	uint64_t		sparse;
> > -	uint16_t		holemask;
> > -	int			error;
> > -
> > -	ASSERT(btnum == XFS_BTNUM_INO || btnum == XFS_BTNUM_FINO);
> > -
> > -	for (i = 0; i < level; i++)  {
> > -		lptr = &btree_curs->level[i];
> > -
> > -		agbno = get_next_blockaddr(agno, i, btree_curs);
> > -		error = -libxfs_buf_get(mp->m_dev,
> > -				XFS_AGB_TO_DADDR(mp, agno, agbno),
> > -				XFS_FSB_TO_BB(mp, 1), &lptr->buf_p);
> > -		if (error)
> > -			do_error(_("Cannot grab inode btree buffer, err=%d"),
> > -					error);
> > -
> > -		if (i == btree_curs->num_levels - 1)
> > -			btree_curs->root = agbno;
> > -
> > -		lptr->agbno = agbno;
> > -		lptr->prev_agbno = NULLAGBLOCK;
> > -		lptr->prev_buf_p = NULL;
> > -		/*
> > -		 * initialize block header
> > -		 */
> > -
> > -		lptr->buf_p->b_ops = ops;
> > -		bt_hdr = XFS_BUF_TO_BLOCK(lptr->buf_p);
> > -		memset(bt_hdr, 0, mp->m_sb.sb_blocksize);
> > -		libxfs_btree_init_block(mp, lptr->buf_p, btnum, i, 0, agno);
> > -	}
> > -
> > -	/*
> > -	 * run along leaf, setting up records.  as we have to switch
> > -	 * blocks, call the prop_ino_cursor routine to set up the new
> > -	 * pointers for the parent.  that can recurse up to the root
> > -	 * if required.  set the sibling pointers for leaf level here.
> > -	 */
> > -	if (btnum == XFS_BTNUM_FINO)
> > -		ino_rec = findfirst_free_inode_rec(agno);
> > -	else
> > -		ino_rec = findfirst_inode_rec(agno);
> > -
> > -	if (ino_rec != NULL)
> > -		first_agino = ino_rec->ino_startnum;
> > -	else
> > -		first_agino = NULLAGINO;
> > -
> > -	lptr = &btree_curs->level[0];
> > -
> > -	for (i = 0; i < lptr->num_blocks; i++)  {
> > -		/*
> > -		 * block initialization, lay in block header
> > -		 */
> > -		lptr->buf_p->b_ops = ops;
> > -		bt_hdr = XFS_BUF_TO_BLOCK(lptr->buf_p);
> > -		memset(bt_hdr, 0, mp->m_sb.sb_blocksize);
> > -		libxfs_btree_init_block(mp, lptr->buf_p, btnum, 0, 0, agno);
> > -
> > -		bt_hdr->bb_u.s.bb_leftsib = cpu_to_be32(lptr->prev_agbno);
> > -		bt_hdr->bb_numrecs = cpu_to_be16(lptr->num_recs_pb +
> > -							(lptr->modulo > 0));
> > -
> > -		if (lptr->modulo > 0)
> > -			lptr->modulo--;
> > -
> > -		if (lptr->num_recs_pb > 0)
> > -			prop_ino_cursor(mp, agno, btree_curs, btnum,
> > -					ino_rec->ino_startnum, 0);
> > -
> > -		bt_rec = (xfs_inobt_rec_t *)
> > -			  ((char *)bt_hdr + XFS_INOBT_BLOCK_LEN(mp));
> > -		for (j = 0; j < be16_to_cpu(bt_hdr->bb_numrecs); j++) {
> > -			ASSERT(ino_rec != NULL);
> > -			bt_rec[j].ir_startino =
> > -					cpu_to_be32(ino_rec->ino_startnum);
> > -			bt_rec[j].ir_free = cpu_to_be64(ino_rec->ir_free);
> > -
> > -			inocnt = finocnt = 0;
> > -			for (k = 0; k < sizeof(xfs_inofree_t)*NBBY; k++)  {
> > -				ASSERT(is_inode_confirmed(ino_rec, k));
> > -
> > -				if (is_inode_sparse(ino_rec, k))
> > -					continue;
> > -				if (is_inode_free(ino_rec, k))
> > -					finocnt++;
> > -				inocnt++;
> > -			}
> > -
> > -			/*
> > -			 * Set the freecount and check whether we need to update
> > -			 * the sparse format fields. Otherwise, skip to the next
> > -			 * record.
> > -			 */
> > -			inorec_set_freecount(mp, &bt_rec[j], finocnt);
> > -			if (!xfs_sb_version_hassparseinodes(&mp->m_sb))
> > -				goto nextrec;
> > -
> > -			/*
> > -			 * Convert the 64-bit in-core sparse inode state to the
> > -			 * 16-bit on-disk holemask.
> > -			 */
> > -			holemask = 0;
> > -			spmask = (1 << XFS_INODES_PER_HOLEMASK_BIT) - 1;
> > -			sparse = ino_rec->ir_sparse;
> > -			for (k = 0; k < XFS_INOBT_HOLEMASK_BITS; k++) {
> > -				if (sparse & spmask) {
> > -					ASSERT((sparse & spmask) == spmask);
> > -					holemask |= (1 << k);
> > -				} else
> > -					ASSERT((sparse & spmask) == 0);
> > -				sparse >>= XFS_INODES_PER_HOLEMASK_BIT;
> > -			}
> > -
> > -			bt_rec[j].ir_u.sp.ir_count = inocnt;
> > -			bt_rec[j].ir_u.sp.ir_holemask = cpu_to_be16(holemask);
> > -
> > -nextrec:
> > -			freecount += finocnt;
> > -			count += inocnt;
> > -
> > -			if (btnum == XFS_BTNUM_FINO)
> > -				ino_rec = next_free_ino_rec(ino_rec);
> > -			else
> > -				ino_rec = next_ino_rec(ino_rec);
> > -		}
> > -
> > -		if (ino_rec != NULL)  {
> > -			/*
> > -			 * get next leaf level block
> > -			 */
> > -			if (lptr->prev_buf_p != NULL)  {
> > -#ifdef XR_BLD_INO_TRACE
> > -				fprintf(stderr, "writing inobt agbno %u\n",
> > -					lptr->prev_agbno);
> > -#endif
> > -				ASSERT(lptr->prev_agbno != NULLAGBLOCK);
> > -				libxfs_buf_mark_dirty(lptr->prev_buf_p);
> > -				libxfs_buf_relse(lptr->prev_buf_p);
> > -			}
> > -			lptr->prev_buf_p = lptr->buf_p;
> > -			lptr->prev_agbno = lptr->agbno;
> > -			lptr->agbno = get_next_blockaddr(agno, 0, btree_curs);
> > -			bt_hdr->bb_u.s.bb_rightsib = cpu_to_be32(lptr->agbno);
> > -
> > -			error = -libxfs_buf_get(mp->m_dev,
> > -					XFS_AGB_TO_DADDR(mp, agno, lptr->agbno),
> > -					XFS_FSB_TO_BB(mp, 1),
> > -					&lptr->buf_p);
> > -			if (error)
> > -				do_error(
> > -	_("Cannot grab inode btree buffer, err=%d"),
> > -						error);
> > -		}
> > -	}
> > -
> > -	if (agi_stat) {
> > -		agi_stat->first_agino = first_agino;
> > -		agi_stat->count = count;
> > -		agi_stat->freecount = freecount;
> > -	}
> > -}
> > -
> >  /* rebuild the rmap tree */
> >  
> >  /*
> > @@ -1744,15 +1339,10 @@ phase5_func(
> >  	struct xfs_slab		*lost_fsb)
> >  {
> >  	struct repair_ctx	sc = { .mp = mp, };
> > -	struct agi_stat		agi_stat = {0,};
> > -	uint64_t		num_inos;
> > -	uint64_t		num_free_inos;
> > -	uint64_t		finobt_num_inos;
> > -	uint64_t		finobt_num_free_inos;
> >  	struct bt_rebuild	btr_bno;
> >  	struct bt_rebuild	btr_cnt;
> > -	bt_status_t		ino_btree_curs;
> > -	bt_status_t		fino_btree_curs;
> > +	struct bt_rebuild	btr_ino;
> > +	struct bt_rebuild	btr_fino;
> >  	bt_status_t		rmap_btree_curs;
> >  	bt_status_t		refcnt_btree_curs;
> >  	int			extra_blocks = 0;
> > @@ -1785,19 +1375,8 @@ _("unable to rebuild AG %u.  Not enough free space in on-disk AG.\n"),
> >  			agno);
> >  	}
> >  
> > -	/*
> > -	 * ok, now set up the btree cursors for the on-disk btrees (includes
> > -	 * pre-allocating all required blocks for the trees themselves)
> > -	 */
> > -	init_ino_cursor(mp, agno, &ino_btree_curs, &num_inos,
> > -			&num_free_inos, 0);
> > -
> > -	if (xfs_sb_version_hasfinobt(&mp->m_sb))
> > -		init_ino_cursor(mp, agno, &fino_btree_curs, &finobt_num_inos,
> > -				&finobt_num_free_inos, 1);
> > -
> > -	sb_icount_ag[agno] += num_inos;
> > -	sb_ifree_ag[agno] += num_free_inos;
> > +	init_ino_cursors(&sc, agno, num_freeblocks, &sb_icount_ag[agno],
> > +			&sb_ifree_ag[agno], &btr_ino, &btr_fino);
> >  
> >  	/*
> >  	 * Set up the btree cursors for the on-disk rmap btrees, which includes
> > @@ -1886,36 +1465,23 @@ _("unable to rebuild AG %u.  Not enough free space in on-disk AG.\n"),
> >  	build_agf_agfl(mp, agno, &btr_bno, &btr_cnt, &rmap_btree_curs,
> >  			&refcnt_btree_curs, lost_fsb);
> >  
> > -	/*
> > -	 * build inode allocation tree.
> > -	 */
> > -	build_ino_tree(mp, agno, &ino_btree_curs, XFS_BTNUM_INO, &agi_stat);
> > -	write_cursor(&ino_btree_curs);
> > -
> > -	/*
> > -	 * build free inode tree
> > -	 */
> > -	if (xfs_sb_version_hasfinobt(&mp->m_sb)) {
> > -		build_ino_tree(mp, agno, &fino_btree_curs,
> > -				XFS_BTNUM_FINO, NULL);
> > -		write_cursor(&fino_btree_curs);
> > -	}
> > +	build_inode_btrees(&sc, agno, &btr_ino, &btr_fino);
> >  
> >  	/* build the agi */
> > -	build_agi(mp, agno, &ino_btree_curs, &fino_btree_curs, &agi_stat);
> > +	build_agi(mp, agno, &btr_ino, &btr_fino);
> >  
> >  	/*
> >  	 * tear down cursors
> >  	 */
> >  	finish_rebuild(mp, &btr_bno, lost_fsb);
> >  	finish_rebuild(mp, &btr_cnt, lost_fsb);
> > -	finish_cursor(&ino_btree_curs);
> > +	finish_rebuild(mp, &btr_ino, lost_fsb);
> > +	if (xfs_sb_version_hasfinobt(&mp->m_sb))
> > +		finish_rebuild(mp, &btr_fino, lost_fsb);
> >  	if (xfs_sb_version_hasrmapbt(&mp->m_sb))
> >  		finish_cursor(&rmap_btree_curs);
> >  	if (xfs_sb_version_hasreflink(&mp->m_sb))
> >  		finish_cursor(&refcnt_btree_curs);
> > -	if (xfs_sb_version_hasfinobt(&mp->m_sb))
> > -		finish_cursor(&fino_btree_curs);
> >  
> >  	/*
> >  	 * release the incore per-AG bno/bcnt trees so the extent nodes
> > 
> 