linux/fs/xfs/scrub/bmap_repair.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Copyright (C) 2018-2023 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_trans_resv.h"
#include "xfs_mount.h"
#include "xfs_defer.h"
#include "xfs_btree.h"
#include "xfs_btree_staging.h"
#include "xfs_bit.h"
#include "xfs_log_format.h"
#include "xfs_trans.h"
#include "xfs_sb.h"
#include "xfs_inode.h"
#include "xfs_inode_fork.h"
#include "xfs_alloc.h"
#include "xfs_rtalloc.h"
#include "xfs_bmap.h"
#include "xfs_bmap_util.h"
#include "xfs_bmap_btree.h"
#include "xfs_rmap.h"
#include "xfs_rmap_btree.h"
#include "xfs_refcount.h"
#include "xfs_quota.h"
#include "xfs_ialloc.h"
#include "xfs_ag.h"
#include "xfs_reflink.h"
#include "scrub/xfs_scrub.h"
#include "scrub/scrub.h"
#include "scrub/common.h"
#include "scrub/btree.h"
#include "scrub/trace.h"
#include "scrub/repair.h"
#include "scrub/bitmap.h"
#include "scrub/fsb_bitmap.h"
#include "scrub/xfile.h"
#include "scrub/xfarray.h"
#include "scrub/newbt.h"
#include "scrub/reap.h"

/*
 * Inode Fork Block Mapping (BMBT) Repair
 * ======================================
 *
 * Gather all the rmap records for the inode and fork we're fixing, reset the
 * incore fork, then recreate the btree.
 */

enum reflink_scan_state { … };

struct xrep_bmap { … };

/* Is this space extent shared?  Flag the inode if it is. */
STATIC int
xrep_bmap_discover_shared(
	struct xrep_bmap	*rb,
	xfs_fsblock_t		startblock,
	xfs_filblks_t		blockcount)
{ … }

/* Remember this reverse-mapping as a series of bmap records. */
STATIC int
xrep_bmap_from_rmap(
	struct xrep_bmap	*rb,
	xfs_fileoff_t		startoff,
	xfs_fsblock_t		startblock,
	xfs_filblks_t		blockcount,
	bool			unwritten)
{ … }

/* Check for any obvious errors or conflicts in the file mapping. */
STATIC int
xrep_bmap_check_fork_rmap(
	struct xrep_bmap		*rb,
	struct xfs_btree_cur		*cur,
	const struct xfs_rmap_irec	*rec)
{ … }

/* Record extents that belong to this inode's fork. */
STATIC int
xrep_bmap_walk_rmap(
	struct xfs_btree_cur		*cur,
	const struct xfs_rmap_irec	*rec,
	void				*priv)
{ … }

/*
 * Compare two block mapping records.  We want to sort in order of increasing
 * file offset.
 */
static int
xrep_bmap_extent_cmp(
	const void			*a,
	const void			*b)
{ … }

/*
 * Sort the bmap extents by fork offset or else the records will be in the
 * wrong order.  Ensure there are no overlaps in the file offset ranges.
 */
STATIC int
xrep_bmap_sort_records(
	struct xrep_bmap	*rb)
{ … }

/* Scan one AG for reverse mappings that we can turn into extent maps. */
STATIC int
xrep_bmap_scan_ag(
	struct xrep_bmap	*rb,
	struct xfs_perag	*pag)
{ … }

/* Find the delalloc extents from the old incore extent tree. */
STATIC int
xrep_bmap_find_delalloc(
	struct xrep_bmap	*rb)
{ … }

/*
 * Collect block mappings for this fork of this inode and decide if we have
 * enough space to rebuild.  Caller is responsible for cleaning up the list if
 * anything goes wrong.
 */
STATIC int
xrep_bmap_find_mappings(
	struct xrep_bmap	*rb)
{ … }

/* Retrieve real extent mappings for bulk loading the bmap btree. */
STATIC int
xrep_bmap_get_records(
	struct xfs_btree_cur	*cur,
	unsigned int		idx,
	struct xfs_btree_block	*block,
	unsigned int		nr_wanted,
	void			*priv)
{ … }

/* Feed one of the new btree blocks to the bulk loader. */
STATIC int
xrep_bmap_claim_block(
	struct xfs_btree_cur	*cur,
	union xfs_btree_ptr	*ptr,
	void			*priv)
{ … }

/* Figure out how much space we need to create the incore btree root block. */
STATIC size_t
xrep_bmap_iroot_size(
	struct xfs_btree_cur	*cur,
	unsigned int		level,
	unsigned int		nr_this_level,
	void			*priv)
{ … }

/* Update the inode counters. */
STATIC int
xrep_bmap_reset_counters(
	struct xrep_bmap	*rb)
{ … }

/*
 * Create a new iext tree and load it with block mappings.  If the inode is
 * in extents format, that's all we need to do to commit the new mappings.
 * If it is in btree format, this takes care of preloading the incore tree.
 */
STATIC int
xrep_bmap_extents_load(
	struct xrep_bmap	*rb)
{ … }

/*
 * Reserve new btree blocks, bulk load the bmap records into the ondisk btree,
 * and load the incore extent tree.
 */
STATIC int
xrep_bmap_btree_load(
	struct xrep_bmap	*rb,
	struct xfs_btree_cur	*bmap_cur)
{ … }

/*
 * Use the collected bmap information to stage a new bmap fork.  If this is
 * successful we'll return with the new fork information logged to the repair
 * transaction but not yet committed.  The caller must ensure that the inode
 * is joined to the transaction; the inode will be joined to a clean
 * transaction when the function returns.
 */
STATIC int
xrep_bmap_build_new_fork(
	struct xrep_bmap	*rb)
{ … }

/*
 * Now that we've logged the new inode btree, invalidate all of the old blocks
 * and free them, if there were any.
 */
STATIC int
xrep_bmap_remove_old_tree(
	struct xrep_bmap	*rb)
{ … }

/* Check for garbage inputs.  Returns -ECANCELED if there's nothing to do. */
STATIC int
xrep_bmap_check_inputs(
	struct xfs_scrub	*sc,
	int			whichfork)
{ … }

/* Set up the initial state of the reflink scan. */
static inline enum reflink_scan_state
xrep_bmap_init_reflink_scan(
	struct xfs_scrub	*sc,
	int			whichfork)
{ … }

/* Repair an inode fork. */
int
xrep_bmap(
	struct xfs_scrub	*sc,
	int			whichfork,
	bool			allow_unwritten)
{ … }

/* Repair an inode's data fork. */
int
xrep_bmap_data(
	struct xfs_scrub	*sc)
{ … }

/* Repair an inode's attr fork. */
int
xrep_bmap_attr(
	struct xfs_scrub	*sc)
{ … }