Commit c7e693d9 authored by Darrick J. Wong's avatar Darrick J. Wong
Browse files

xfs: scrub rmap btrees 



Check the reverse mapping records to make sure that the contents
make sense.

Signed-off-by: default avatarDarrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: default avatarDave Chinner <dchinner@redhat.com>
parent 3daa6641

fs/xfs/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -148,6 +148,7 @@ xfs-y += $(addprefix scrub/, \ 
				   btree.o \

				   common.o \

				   ialloc.o \

				   rmap.o \

				   scrub.o \

				   )

endif

fs/xfs/libxfs/xfs_fs.h

+2 −1
Original line number Diff line number Diff line
@@ -492,9 +492,10 @@ struct xfs_scrub_metadata { 
#define XFS_SCRUB_TYPE_CNTBT	6	/* freesp by length btree */

#define XFS_SCRUB_TYPE_INOBT	7	/* inode btree */

#define XFS_SCRUB_TYPE_FINOBT	8	/* free inode btree */

#define XFS_SCRUB_TYPE_RMAPBT	9	/* reverse mapping btree */



/* Number of scrub subcommands. */

#define XFS_SCRUB_TYPE_NR	9

#define XFS_SCRUB_TYPE_NR	10



/* i: Repair this metadata. */

#define XFS_SCRUB_IFLAG_REPAIR		(1 << 0)

fs/xfs/scrub/common.h

+2 −0
Original line number Diff line number Diff line
@@ -83,6 +83,8 @@ int xfs_scrub_setup_ag_allocbt(struct xfs_scrub_context *sc, 
			       struct xfs_inode *ip);

int xfs_scrub_setup_ag_iallocbt(struct xfs_scrub_context *sc,

				struct xfs_inode *ip);

int xfs_scrub_setup_ag_rmapbt(struct xfs_scrub_context *sc,

			      struct xfs_inode *ip);





void xfs_scrub_ag_free(struct xfs_scrub_context *sc, struct xfs_scrub_ag *sa);

fs/xfs/scrub/rmap.c

0 → 100644
+138 −0
Original line number Diff line number Diff line 
/*

 * Copyright (C) 2017 Oracle.  All Rights Reserved.

 *

 * Author: Darrick J. Wong <darrick.wong@oracle.com>

 *

 * This program is free software; you can redistribute it and/or

 * modify it under the terms of the GNU General Public License

 * as published by the Free Software Foundation; either version 2

 * of the License, or (at your option) any later version.

 *

 * This program is distributed in the hope that it would be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 *

 * You should have received a copy of the GNU General Public License

 * along with this program; if not, write the Free Software Foundation,

 * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301, USA.

 */

#include "xfs.h"

#include "xfs_fs.h"

#include "xfs_shared.h"

#include "xfs_format.h"

#include "xfs_trans_resv.h"

#include "xfs_mount.h"

#include "xfs_defer.h"

#include "xfs_btree.h"

#include "xfs_bit.h"

#include "xfs_log_format.h"

#include "xfs_trans.h"

#include "xfs_sb.h"

#include "xfs_alloc.h"

#include "xfs_ialloc.h"

#include "xfs_rmap.h"

#include "scrub/xfs_scrub.h"

#include "scrub/scrub.h"

#include "scrub/common.h"

#include "scrub/btree.h"

#include "scrub/trace.h"



/*

 * Set us up to scrub reverse mapping btrees.

 */

int

xfs_scrub_setup_ag_rmapbt(

	struct xfs_scrub_context	*sc,

	struct xfs_inode		*ip)

{

	return xfs_scrub_setup_ag_btree(sc, ip, false);

}



/* Reverse-mapping scrubber. */



/* Scrub an rmapbt record. */

STATIC int

xfs_scrub_rmapbt_rec(

	struct xfs_scrub_btree		*bs,

	union xfs_btree_rec		*rec)

{

	struct xfs_mount		*mp = bs->cur->bc_mp;

	struct xfs_rmap_irec		irec;

	xfs_agnumber_t			agno = bs->cur->bc_private.a.agno;

	bool				non_inode;

	bool				is_unwritten;

	bool				is_bmbt;

	bool				is_attr;

	int				error;



	error = xfs_rmap_btrec_to_irec(rec, &irec);

	if (!xfs_scrub_btree_process_error(bs->sc, bs->cur, 0, &error))

		goto out;



	/* Check extent. */

	if (irec.rm_startblock + irec.rm_blockcount <= irec.rm_startblock)

		xfs_scrub_btree_set_corrupt(bs->sc, bs->cur, 0);



	if (irec.rm_owner == XFS_RMAP_OWN_FS) {

		/*

		 * xfs_verify_agbno returns false for static fs metadata.

		 * Since that only exists at the start of the AG, validate

		 * that by hand.

		 */

		if (irec.rm_startblock != 0 ||

		    irec.rm_blockcount != XFS_AGFL_BLOCK(mp) + 1)

			xfs_scrub_btree_set_corrupt(bs->sc, bs->cur, 0);

	} else {

		/*

		 * Otherwise we must point somewhere past the static metadata

		 * but before the end of the FS.  Run the regular check.

		 */

		if (!xfs_verify_agbno(mp, agno, irec.rm_startblock) ||

		    !xfs_verify_agbno(mp, agno, irec.rm_startblock +

				irec.rm_blockcount - 1))

			xfs_scrub_btree_set_corrupt(bs->sc, bs->cur, 0);

	}



	/* Check flags. */

	non_inode = XFS_RMAP_NON_INODE_OWNER(irec.rm_owner);

	is_bmbt = irec.rm_flags & XFS_RMAP_BMBT_BLOCK;

	is_attr = irec.rm_flags & XFS_RMAP_ATTR_FORK;

	is_unwritten = irec.rm_flags & XFS_RMAP_UNWRITTEN;



	if (is_bmbt && irec.rm_offset != 0)

		xfs_scrub_btree_set_corrupt(bs->sc, bs->cur, 0);



	if (non_inode && irec.rm_offset != 0)

		xfs_scrub_btree_set_corrupt(bs->sc, bs->cur, 0);



	if (is_unwritten && (is_bmbt || non_inode || is_attr))

		xfs_scrub_btree_set_corrupt(bs->sc, bs->cur, 0);



	if (non_inode && (is_bmbt || is_unwritten || is_attr))

		xfs_scrub_btree_set_corrupt(bs->sc, bs->cur, 0);



	if (!non_inode) {

		if (!xfs_verify_ino(mp, irec.rm_owner))

			xfs_scrub_btree_set_corrupt(bs->sc, bs->cur, 0);

	} else {

		/* Non-inode owner within the magic values? */

		if (irec.rm_owner <= XFS_RMAP_OWN_MIN ||

		    irec.rm_owner > XFS_RMAP_OWN_FS)

			xfs_scrub_btree_set_corrupt(bs->sc, bs->cur, 0);

	}

out:

	return error;

}



/* Scrub the rmap btree for some AG. */

int

xfs_scrub_rmapbt(

	struct xfs_scrub_context	*sc)

{

	struct xfs_owner_info		oinfo;



	xfs_rmap_ag_owner(&oinfo, XFS_RMAP_OWN_AG);

	return xfs_scrub_btree(sc, sc->sa.rmap_cur, xfs_scrub_rmapbt_rec,

			&oinfo, NULL);

}

fs/xfs/scrub/scrub.c

+5 −0
Original line number Diff line number Diff line
@@ -191,6 +191,11 @@ static const struct xfs_scrub_meta_ops meta_scrub_ops[] = { 
		.scrub	= xfs_scrub_finobt,

		.has	= xfs_sb_version_hasfinobt,

	},

	{ /* rmapbt */

		.setup	= xfs_scrub_setup_ag_rmapbt,

		.scrub	= xfs_scrub_rmapbt,

		.has	= xfs_sb_version_hasrmapbt,

	},

};



/* This isn't a stable feature, warn once per day. */