Commit 13942aa9 authored by Darrick J. Wong's avatar Darrick J. Wong
Browse files

xfs: repair the AGI 



Rebuild the AGI header items with some help from the rmapbt.

Signed-off-by: default avatarDarrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: default avatarBrian Foster <bfoster@redhat.com>
parent 0e93d3f4

fs/xfs/scrub/agheader_repair.c

+217 −0
Original line number Diff line number Diff line
@@ -714,3 +714,220 @@ xrep_agfl( 
	xfs_bitmap_destroy(&agfl_extents);

	return error;

}



/* AGI */



/*

 * Offset within the xrep_find_ag_btree array for each btree type.  Avoid the

 * XFS_BTNUM_ names here to avoid creating a sparse array.

 */

enum {

	XREP_AGI_INOBT = 0,

	XREP_AGI_FINOBT,

	XREP_AGI_END,

	XREP_AGI_MAX

};



/*

 * Given the inode btree roots described by *fab, find the roots, check them

 * for sanity, and pass the root data back out via *fab.

 */

STATIC int

xrep_agi_find_btrees(

	struct xfs_scrub		*sc,

	struct xrep_find_ag_btree	*fab)

{

	struct xfs_buf			*agf_bp;

	struct xfs_mount		*mp = sc->mp;

	int				error;



	/* Read the AGF. */

	error = xfs_alloc_read_agf(mp, sc->tp, sc->sa.agno, 0, &agf_bp);

	if (error)

		return error;

	if (!agf_bp)

		return -ENOMEM;



	/* Find the btree roots. */

	error = xrep_find_ag_btree_roots(sc, agf_bp, fab, NULL);

	if (error)

		return error;



	/* We must find the inobt root. */

	if (!xrep_check_btree_root(sc, &fab[XREP_AGI_INOBT]))

		return -EFSCORRUPTED;



	/* We must find the finobt root if that feature is enabled. */

	if (xfs_sb_version_hasfinobt(&mp->m_sb) &&

	    !xrep_check_btree_root(sc, &fab[XREP_AGI_FINOBT]))

		return -EFSCORRUPTED;



	return 0;

}



/*

 * Reinitialize the AGI header, making an in-core copy of the old contents so

 * that we know which in-core state needs to be reinitialized.

 */

STATIC void

xrep_agi_init_header(

	struct xfs_scrub	*sc,

	struct xfs_buf		*agi_bp,

	struct xfs_agi		*old_agi)

{

	struct xfs_agi		*agi = XFS_BUF_TO_AGI(agi_bp);

	struct xfs_mount	*mp = sc->mp;



	memcpy(old_agi, agi, sizeof(*old_agi));

	memset(agi, 0, BBTOB(agi_bp->b_length));

	agi->agi_magicnum = cpu_to_be32(XFS_AGI_MAGIC);

	agi->agi_versionnum = cpu_to_be32(XFS_AGI_VERSION);

	agi->agi_seqno = cpu_to_be32(sc->sa.agno);

	agi->agi_length = cpu_to_be32(xfs_ag_block_count(mp, sc->sa.agno));

	agi->agi_newino = cpu_to_be32(NULLAGINO);

	agi->agi_dirino = cpu_to_be32(NULLAGINO);

	if (xfs_sb_version_hascrc(&mp->m_sb))

		uuid_copy(&agi->agi_uuid, &mp->m_sb.sb_meta_uuid);



	/* We don't know how to fix the unlinked list yet. */

	memcpy(&agi->agi_unlinked, &old_agi->agi_unlinked,

			sizeof(agi->agi_unlinked));



	/* Mark the incore AGF data stale until we're done fixing things. */

	ASSERT(sc->sa.pag->pagi_init);

	sc->sa.pag->pagi_init = 0;

}



/* Set btree root information in an AGI. */

STATIC void

xrep_agi_set_roots(

	struct xfs_scrub		*sc,

	struct xfs_agi			*agi,

	struct xrep_find_ag_btree	*fab)

{

	agi->agi_root = cpu_to_be32(fab[XREP_AGI_INOBT].root);

	agi->agi_level = cpu_to_be32(fab[XREP_AGI_INOBT].height);



	if (xfs_sb_version_hasfinobt(&sc->mp->m_sb)) {

		agi->agi_free_root = cpu_to_be32(fab[XREP_AGI_FINOBT].root);

		agi->agi_free_level = cpu_to_be32(fab[XREP_AGI_FINOBT].height);

	}

}



/* Update the AGI counters. */

STATIC int

xrep_agi_calc_from_btrees(

	struct xfs_scrub	*sc,

	struct xfs_buf		*agi_bp)

{

	struct xfs_btree_cur	*cur;

	struct xfs_agi		*agi = XFS_BUF_TO_AGI(agi_bp);

	struct xfs_mount	*mp = sc->mp;

	xfs_agino_t		count;

	xfs_agino_t		freecount;

	int			error;



	cur = xfs_inobt_init_cursor(mp, sc->tp, agi_bp, sc->sa.agno,

			XFS_BTNUM_INO);

	error = xfs_ialloc_count_inodes(cur, &count, &freecount);

	if (error)

		goto err;

	xfs_btree_del_cursor(cur, error);



	agi->agi_count = cpu_to_be32(count);

	agi->agi_freecount = cpu_to_be32(freecount);

	return 0;

err:

	xfs_btree_del_cursor(cur, error);

	return error;

}



/* Trigger reinitialization of the in-core data. */

STATIC int

xrep_agi_commit_new(

	struct xfs_scrub	*sc,

	struct xfs_buf		*agi_bp)

{

	struct xfs_perag	*pag;

	struct xfs_agi		*agi = XFS_BUF_TO_AGI(agi_bp);



	/* Trigger inode count recalculation */

	xfs_force_summary_recalc(sc->mp);



	/* Write this to disk. */

	xfs_trans_buf_set_type(sc->tp, agi_bp, XFS_BLFT_AGI_BUF);

	xfs_trans_log_buf(sc->tp, agi_bp, 0, BBTOB(agi_bp->b_length) - 1);



	/* Now reinitialize the in-core counters if necessary. */

	pag = sc->sa.pag;

	pag->pagi_count = be32_to_cpu(agi->agi_count);

	pag->pagi_freecount = be32_to_cpu(agi->agi_freecount);

	pag->pagi_init = 1;



	return 0;

}



/* Repair the AGI. */

int

xrep_agi(

	struct xfs_scrub		*sc)

{

	struct xrep_find_ag_btree	fab[XREP_AGI_MAX] = {

		[XREP_AGI_INOBT] = {

			.rmap_owner = XFS_RMAP_OWN_INOBT,

			.buf_ops = &xfs_inobt_buf_ops,

			.magic = XFS_IBT_CRC_MAGIC,

		},

		[XREP_AGI_FINOBT] = {

			.rmap_owner = XFS_RMAP_OWN_INOBT,

			.buf_ops = &xfs_inobt_buf_ops,

			.magic = XFS_FIBT_CRC_MAGIC,

		},

		[XREP_AGI_END] = {

			.buf_ops = NULL

		},

	};

	struct xfs_agi			old_agi;

	struct xfs_mount		*mp = sc->mp;

	struct xfs_buf			*agi_bp;

	struct xfs_agi			*agi;

	int				error;



	/* We require the rmapbt to rebuild anything. */

	if (!xfs_sb_version_hasrmapbt(&mp->m_sb))

		return -EOPNOTSUPP;



	xchk_perag_get(sc->mp, &sc->sa);

	/*

	 * Make sure we have the AGI buffer, as scrub might have decided it

	 * was corrupt after xfs_ialloc_read_agi failed with -EFSCORRUPTED.

	 */

	error = xfs_trans_read_buf(mp, sc->tp, mp->m_ddev_targp,

			XFS_AG_DADDR(mp, sc->sa.agno, XFS_AGI_DADDR(mp)),

			XFS_FSS_TO_BB(mp, 1), 0, &agi_bp, NULL);

	if (error)

		return error;

	agi_bp->b_ops = &xfs_agi_buf_ops;

	agi = XFS_BUF_TO_AGI(agi_bp);



	/* Find the AGI btree roots. */

	error = xrep_agi_find_btrees(sc, fab);

	if (error)

		return error;



	/* Start rewriting the header and implant the btrees we found. */

	xrep_agi_init_header(sc, agi_bp, &old_agi);

	xrep_agi_set_roots(sc, agi, fab);

	error = xrep_agi_calc_from_btrees(sc, agi_bp);

	if (error)

		goto out_revert;



	/* Reinitialize in-core state. */

	return xrep_agi_commit_new(sc, agi_bp);



out_revert:

	/* Mark the incore AGI state stale and revert the AGI. */

	sc->sa.pag->pagi_init = 0;

	memcpy(agi, &old_agi, sizeof(old_agi));

	return error;

}

fs/xfs/scrub/repair.h

+2 −0
Original line number Diff line number Diff line
@@ -60,6 +60,7 @@ int xrep_probe(struct xfs_scrub *sc); 
int xrep_superblock(struct xfs_scrub *sc);

int xrep_agf(struct xfs_scrub *sc);

int xrep_agfl(struct xfs_scrub *sc);

int xrep_agi(struct xfs_scrub *sc);



#else
@@ -85,6 +86,7 @@ xrep_calc_ag_resblks( 
#define xrep_superblock			xrep_notsupported

#define xrep_agf			xrep_notsupported

#define xrep_agfl			xrep_notsupported

#define xrep_agi			xrep_notsupported



#endif /* CONFIG_XFS_ONLINE_REPAIR */

fs/xfs/scrub/scrub.c

+1 −1
Original line number Diff line number Diff line
@@ -226,7 +226,7 @@ static const struct xchk_meta_ops meta_scrub_ops[] = { 
		.type	= ST_PERAG,

		.setup	= xchk_setup_fs,

		.scrub	= xchk_agi,

		.repair	= xrep_notsupported,

		.repair	= xrep_agi,

	},

	[XFS_SCRUB_TYPE_BNOBT] = {	/* bnobt */

		.type	= ST_PERAG,