linux/fs/xfs/scrub/rmap.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Copyright (C) 2017-2023 Oracle.  All Rights Reserved.
 * Author: Darrick J. Wong <[email protected]>
 */
#include "xfs.h"
#include "xfs_fs.h"
#include "xfs_shared.h"
#include "xfs_format.h"
#include "xfs_log_format.h"
#include "xfs_trans_resv.h"
#include "xfs_mount.h"
#include "xfs_trans.h"
#include "xfs_btree.h"
#include "xfs_rmap.h"
#include "xfs_refcount.h"
#include "xfs_ag.h"
#include "xfs_bit.h"
#include "xfs_alloc.h"
#include "xfs_alloc_btree.h"
#include "xfs_ialloc_btree.h"
#include "xfs_refcount_btree.h"
#include "scrub/scrub.h"
#include "scrub/common.h"
#include "scrub/btree.h"
#include "scrub/bitmap.h"
#include "scrub/agb_bitmap.h"
#include "scrub/repair.h"

/*
 * Set us up to scrub reverse mapping btrees.
 */
int
xchk_setup_ag_rmapbt(
	struct xfs_scrub	*sc)
{ … }

/* Reverse-mapping scrubber. */

struct xchk_rmap { … };

/* Cross-reference a rmap against the refcount btree. */
STATIC void
xchk_rmapbt_xref_refc(
	struct xfs_scrub	*sc,
	struct xfs_rmap_irec	*irec)
{ … }

/* Cross-reference with the other btrees. */
STATIC void
xchk_rmapbt_xref(
	struct xfs_scrub	*sc,
	struct xfs_rmap_irec	*irec)
{ … }

/*
 * Check for bogus UNWRITTEN flags in the rmapbt node block keys.
 *
 * In reverse mapping records, the file mapping extent state
 * (XFS_RMAP_OFF_UNWRITTEN) is a record attribute, not a key field.  It is not
 * involved in lookups in any way.  In older kernels, the functions that
 * convert rmapbt records to keys forgot to filter out the extent state bit,
 * even though the key comparison functions have filtered the flag correctly.
 * If we spot an rmap key with the unwritten bit set in rm_offset, we should
 * mark the btree as needing optimization to rebuild the btree without those
 * flags.
 */
STATIC void
xchk_rmapbt_check_unwritten_in_keyflags(
	struct xchk_btree	*bs)
{ … }

static inline bool
xchk_rmapbt_is_shareable(
	struct xfs_scrub		*sc,
	const struct xfs_rmap_irec	*irec)
{ … }

/* Flag failures for records that overlap but cannot. */
STATIC void
xchk_rmapbt_check_overlapping(
	struct xchk_btree		*bs,
	struct xchk_rmap		*cr,
	const struct xfs_rmap_irec	*irec)
{ … }

/* Decide if two reverse-mapping records can be merged. */
static inline bool
xchk_rmap_mergeable(
	struct xchk_rmap		*cr,
	const struct xfs_rmap_irec	*r2)
{ … }

/* Flag failures for records that could be merged. */
STATIC void
xchk_rmapbt_check_mergeable(
	struct xchk_btree		*bs,
	struct xchk_rmap		*cr,
	const struct xfs_rmap_irec	*irec)
{ … }

/* Compare an rmap for AG metadata against the metadata walk. */
STATIC int
xchk_rmapbt_mark_bitmap(
	struct xchk_btree		*bs,
	struct xchk_rmap		*cr,
	const struct xfs_rmap_irec	*irec)
{ … }

/* Scrub an rmapbt record. */
STATIC int
xchk_rmapbt_rec(
	struct xchk_btree	*bs,
	const union xfs_btree_rec *rec)
{ … }

/* Add an AGFL block to the rmap list. */
STATIC int
xchk_rmapbt_walk_agfl(
	struct xfs_mount	*mp,
	xfs_agblock_t		agbno,
	void			*priv)
{ … }

/*
 * Set up bitmaps mapping all the AG metadata to compare with the rmapbt
 * records.
 *
 * Grab our own btree cursors here if the scrub setup function didn't give us a
 * btree cursor due to reports of poor health.  We need to find out if the
 * rmapbt disagrees with primary metadata btrees to tag the rmapbt as being
 * XCORRUPT.
 */
STATIC int
xchk_rmapbt_walk_ag_metadata(
	struct xfs_scrub	*sc,
	struct xchk_rmap	*cr)
{ … }

/*
 * Check for set regions in the bitmaps; if there are any, the rmap records do
 * not describe all the AG metadata.
 */
STATIC void
xchk_rmapbt_check_bitmaps(
	struct xfs_scrub	*sc,
	struct xchk_rmap	*cr)
{ … }

/* Scrub the rmap btree for some AG. */
int
xchk_rmapbt(
	struct xfs_scrub	*sc)
{ … }

/* xref check that the extent is owned only by a given owner */
void
xchk_xref_is_only_owned_by(
	struct xfs_scrub		*sc,
	xfs_agblock_t			bno,
	xfs_extlen_t			len,
	const struct xfs_owner_info	*oinfo)
{ … }

/* xref check that the extent is not owned by a given owner */
void
xchk_xref_is_not_owned_by(
	struct xfs_scrub		*sc,
	xfs_agblock_t			bno,
	xfs_extlen_t			len,
	const struct xfs_owner_info	*oinfo)
{ … }

/* xref check that the extent has no reverse mapping at all */
void
xchk_xref_has_no_owner(
	struct xfs_scrub	*sc,
	xfs_agblock_t		bno,
	xfs_extlen_t		len)
{ … }