// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (C) 2018 Oracle. All Rights Reserved.
* Author: Darrick J. Wong <darrick.wong@oracle.com>
*/
#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_inode.h"
#include "xfs_alloc.h"
#include "xfs_alloc_btree.h"
#include "xfs_ialloc.h"
#include "xfs_ialloc_btree.h"
#include "xfs_rmap.h"
#include "xfs_rmap_btree.h"
#include "xfs_refcount.h"
#include "xfs_refcount_btree.h"
#include "scrub/xfs_scrub.h"
#include "scrub/scrub.h"
#include "scrub/common.h"
#include "scrub/trace.h"
#include "scrub/repair.h"
#include "scrub/bitmap.h"
/* Superblock */
/* Repair the superblock. */
int
xrep_superblock(
struct xfs_scrub *sc)
{
struct xfs_mount *mp = sc->mp;
struct xfs_buf *bp;
xfs_agnumber_t agno;
int error;
/* Don't try to repair AG 0's sb; let xfs_repair deal with it. */
agno = sc->sm->sm_agno;
if (agno == 0)
return -EOPNOTSUPP;
error = xfs_sb_get_secondary(mp, sc->tp, agno, &bp);
if (error)
return error;
/* Copy AG 0's superblock to this one. */
xfs_buf_zero(bp, 0, BBTOB(bp->b_length));
xfs_sb_to_disk(XFS_BUF_TO_SBP(bp), &mp->m_sb);
/* Write this to disk. */
xfs_trans_buf_set_type(sc->tp, bp, XFS_BLFT_SB_BUF);
xfs_trans_log_buf(sc->tp, bp, 0, BBTOB(bp->b_length) - 1);
return error;
}
/* AGF */
struct xrep_agf_allocbt {
struct xfs_scrub *sc;
xfs_agblock_t freeblks;
xfs_agblock_t longest;
};
/* Record free space shape information. */
STATIC int
xrep_agf_walk_allocbt(
struct xfs_btree_cur *cur,
struct xfs_alloc_rec_incore *rec,
void *priv)
{
struct xrep_agf_allocbt *raa = priv;
int error = 0;
if (xchk_should_terminate(raa->sc, &error))
return error;
raa->freeblks += rec->ar_blockcount;
if (rec->ar_blockcount > raa->longest)
raa->longest = rec->ar_blockcount;
return error;
}
/* Does this AGFL block look sane? */
STATIC int
xrep_agf_check_agfl_block(
struct xfs_mount *mp,
xfs_agblock_t agbno,
void *priv)
{
struct xfs_scrub *sc = priv;
if (!xfs_verify_agbno(mp, sc->sa.agno, agbno))
return -EFSCORRUPTED;
return 0;
}
/*
* 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_AGF_BNOBT = 0,
XREP_AGF_CNTBT,
XREP_AGF_RMAPBT,
XREP_AGF_REFCOUNTBT,
XREP_AGF_END,
XREP_AGF_MAX
};
/* Check a btree root candidate. */
static inline bool
xrep_check_btree_root(
struct xfs_scrub *sc,
struct xrep_find_ag_btree *fab)
{
struct xfs_mount *mp = sc->mp;
xfs_agnumber_t agno = sc->sm->sm_agno;
return xfs_verify_agbno(mp, agno, fab->root) &&
fab->height <= XFS_BTREE_MAXLEVELS;
}
/*
* Given the btree roots described by *fab, find the roots, check them for
* sanity, and pass the root data back out via *fab.
*
* This is /also/ a chicken and egg problem because we have to use the rmapbt
* (rooted in the AGF) to find the btrees rooted in the AGF. We also have no
* idea if the btrees make any sense. If we hit obvious corruptions in those
* btrees we'll bail out.
*/
STATIC int
xrep_agf_find_btrees(
struct xfs_scrub *sc,
struct xfs_buf *agf_bp,
struct xrep_find_ag_btree *fab,
struct xfs_buf *agfl_bp)
{
struct xfs_agf *old_agf = XFS_BUF_TO_AGF(agf_bp);
int error;
/* Go find the root data. */
error = xrep_find_ag_btree_roots(sc, agf_bp, fab, agfl_bp);
if (error)
return error;
/* We must find the bnobt, cntbt, and rmapbt roots. */
if (!xrep_check_btree_root(sc, &fab[XREP_AGF_BNOBT]) ||
!xrep_check_btree_root(sc, &fab[XREP_AGF_CNTBT]) ||
!xrep_check_btree_root(sc, &fab[XREP_AGF_RMAPBT]))
return -EFSCORRUPTED;
/*
* We relied on the rmapbt to reconstruct the AGF. If we get a
* different root then something's seriously wrong.
*/
if (fab[XREP_AGF_RMAPBT].root !=
be32_to_cpu(old_agf->agf_roots[XFS_BTNUM_RMAPi]))
return -EFSCORRUPTED;
/* We must find the refcountbt root if that feature is enabled. */
if (xfs_sb_version_hasreflink(&sc->mp->m_sb) &&
!xrep_check_btree_root(sc, &fab[XREP_AGF_REFCOUNTBT]))
return -EFSCORRUPTED;
return 0;
}
/*
* Reinitialize the AGF 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_agf_init_header(
struct xfs_scrub *sc,
struct xfs_buf *agf_bp,
struct xfs_agf *old_agf)
{
struct xfs_mount *mp = sc->mp;
struct xfs_agf *agf = XFS_BUF_TO_AGF(agf_bp);
memcpy(old_agf, agf, sizeof(*old_agf));
memset(agf, 0, BBTOB(agf_bp->b_length));
agf->agf_magicnum = cpu_to_be32(XFS_AGF_MAGIC);
agf->agf_versionnum = cpu_to_be32(XFS_AGF_VERSION);
agf->agf_seqno = cpu_to_be32(sc->sa.agno);
agf->agf_length = cpu_to_be32(xfs_ag_block_count(mp, sc->sa.agno));
agf->agf_flfirst = old_agf->agf_flfirst;
agf->agf_fllast = old_agf->agf_fllast;
agf->agf_flcount = old_agf->agf_flcount;
if (xfs_sb_version_hascrc(&mp->m_sb))
uuid_copy(&agf->agf_uuid, &mp->m_sb.sb_meta_uuid);
/* Mark the incore AGF data stale until we're done fixing things. */
ASSERT(sc->sa.pag->pagf_init);
sc->sa.pag->pagf_init = 0;
}
/* Set btree root information in an AGF. */
STATIC void
xrep_agf_set_roots(
struct xfs_scrub *sc,
struct xfs_agf *agf,
struct xrep_find_ag_btree *fab)
{
agf->agf_roots[XFS_BTNUM_BNOi] =
cpu_to_be32(fab[XREP_AGF_BNOBT].root);
agf->agf_levels[XFS_BTNUM_BNOi] =
cpu_to_be32(fab[XREP_AGF_BNOBT].height);
agf->agf_roots[XFS_BTNUM_CNTi] =
cpu_to_be32(fab[XREP_AGF_CNTBT].root);
agf->agf_levels[XFS_BTNUM_CNTi] =
cpu_to_be32(fab[XREP_AGF_CNTBT].height);
agf->agf_roots[XFS_BTNUM_RMAPi] =
cpu_to_be32(fab[XREP_AGF_RMAPBT].root);
agf->agf_levels[XFS_BTNUM_RMAPi] =
cpu_to_be32(fab[XREP_AGF_RMAPBT].height);
if (xfs_sb_version_hasreflink(&sc->mp->m_sb)) {
agf->agf_refcount_root =
cpu_to_be32(fab[XREP_AGF_REFCOUNTBT].root);
agf->agf_refcount_level =
cpu_to_be32(fab[XREP_AGF_REFCOUNTBT].height);
}
}
/* Update all AGF fields which derive from btree contents. */
STATIC int
xrep_agf_calc_from_btrees(
struct xfs_scrub *sc,
struct xfs_buf *agf_bp)
{
struct xrep_agf_allocbt raa = { .sc = sc };
struct xfs_btree_cur *cur = NULL;
struct xfs_agf *agf = XFS_BUF_TO_AGF(agf_bp);
struct xfs_mount *mp = sc->mp;
xfs_agblock_t btreeblks;
xfs_agblock_t blocks;
int error;
/* Update the AGF counters from the bnobt. */
cur = xfs_allocbt_init_cursor(mp, sc->tp, agf_bp, sc->sa.agno,
XFS_BTNUM_BNO);
error = xfs_alloc_query_all(cur, xrep_agf_walk_allocbt, &raa);
if (error)
goto err;
error = xfs_btree_count_blocks(cur, &blocks);
if (error)
goto err;
xfs_btree_del_cursor(cur, error);
btreeblks = blocks - 1;
agf->agf_freeblks = cpu_to_be32(raa.freeblks);
agf->agf_longest = cpu_to_be32(raa.longest);
/* Update the AGF counters from the cntbt. */
cur = xfs_allocbt_init_cursor(mp, sc->tp, agf_bp, sc->sa.agno,
XFS_BTNUM_CNT);
error = xfs_btree_count_blocks(cur, &blocks);
if (error)
goto err;
xfs_btree_del_cursor(cur, error);
btreeblks += blocks - 1;
/* Update the AGF counters from the rmapbt. */
cur = xfs_rmapbt_init_cursor(mp, sc->tp, agf_bp, sc->sa.agno);
error = xfs_btree_count_blocks(cur, &blocks);
if (error)
goto err;
xfs_btree_del_cursor(cur, error);
agf->agf_rmap_blocks = cpu_to_be32(blocks);
btreeblks += blocks - 1;
agf->agf_btreeblks = cpu_to_be32(btreeblks);
/* Update the AGF counters from the refcountbt. */
if (xfs_sb_version_hasreflink(&mp->m_sb)) {
cur = xfs_refcountbt_init_cursor(mp, sc->tp, agf_bp,
sc->sa.agno);
error = xfs_btree_count_blocks(cur, &blocks);
if (error)
goto err;
xfs_btree_del_cursor(cur, error);
agf->agf_refcount_blocks = cpu_to_be32(blocks);
}
return 0;
err:
xfs_btree_del_cursor(cur, error);
return error;
}
/* Commit the new AGF and reinitialize the incore state. */
STATIC int
xrep_agf_commit_new(
struct xfs_scrub *sc,
struct xfs_buf *agf_bp)
{
struct xfs_perag *pag;
struct xfs_agf *agf = XFS_BUF_TO_AGF(agf_bp);
/* Trigger fdblocks recalculation */
xfs_force_summary_recalc(sc->mp);
/* Write this to disk. */
xfs_trans_buf_set_type(sc->tp, agf_bp, XFS_BLFT_AGF_BUF);
xfs_trans_log_buf(sc->tp, agf_bp, 0, BBTOB(agf_bp->b_length) - 1);
/* Now reinitialize the in-core counters we changed. */
pag = sc->sa.pag;
pag->pagf_btreeblks = be32_to_cpu(agf->agf_btreeblks);
pag->pagf_freeblks = be32_to_cpu(agf->agf_freeblks);
pag->pagf_longest = be32_to_cpu(agf->agf_longest);
pag->pagf_levels[XFS_BTNUM_BNOi] =
be32_to_cpu(agf->agf_levels[XFS_BTNUM_BNOi]);
pag->pagf_levels[XFS_BTNUM_CNTi] =
be32_to_cpu(agf->agf_levels[XFS_BTNUM_CNTi]);
pag->pagf_levels[XFS_BTNUM_RMAPi] =
be32_to_cpu(agf->agf_levels[XFS_BTNUM_RMAPi]);
pag->pagf_refcount_level = be32_to_cpu(agf->agf_refcount_level);
pag->pagf_init = 1;
return 0;
}
/* Repair the AGF. v5 filesystems only. */
int
xrep_agf(
struct xfs_scrub *sc)
{
struct xrep_find_ag_btree fab[XREP_AGF_MAX] = {
[XREP_AGF_BNOBT] = {
.rmap_owner = XFS_RMAP_OWN_AG,
.buf_ops = &xfs_allocbt_buf_ops,
.magic = XFS_ABTB_CRC_MAGIC,
},
[XREP_AGF_CNTBT] = {
.rmap_owner = XFS_RMAP_OWN_AG,
.buf_ops = &xfs_allocbt_buf_ops,
.magic = XFS_ABTC_CRC_MAGIC,
},
[XREP_AGF_RMAPBT] = {
.rmap_owner = XFS_RMAP_OWN_AG,
.buf_ops = &xfs_rmapbt_buf_ops,
.magic = XFS_RMAP_CRC_MAGIC,
},
[XREP_AGF_REFCOUNTBT] = {
.rmap_owner = XFS_RMAP_OWN_REFC,
.buf_ops = &xfs_refcountbt_buf_ops,
.magic = XFS_REFC_CRC_MAGIC,
},
[XREP_AGF_END] = {
.buf_ops = NULL,
},
};
struct xfs_agf old_agf;
struct xfs_mount *mp = sc->mp;
struct xfs_buf *agf_bp;
struct xfs_buf *agfl_bp;
struct xfs_agf *agf;
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 AGF buffer, as scrub might have decided it
* was corrupt after xfs_alloc_read_agf failed with -EFSCORRUPTED.
*/
error = xfs_trans_read_buf(mp, sc->tp, mp->m_ddev_targp,
XFS_AG_DADDR(mp, sc->sa.agno, XFS_AGF_DADDR(mp)),
XFS_FSS_TO_BB(mp, 1), 0, &agf_bp, NULL);
if (error)
return error;
agf_bp->b_ops = &xfs_agf_buf_ops;
agf = XFS_BUF_TO_AGF(agf_bp);
/*
* Load the AGFL so that we can screen out OWN_AG blocks that are on
* the AGFL now; these blocks might have once been part of the
* bno/cnt/rmap btrees but are not now. This is a chicken and egg
* problem: the AGF is corrupt, so we have to trust the AGFL contents
* because we can't do any serious cross-referencing with any of the
* btrees rooted in the AGF. If the AGFL contents are obviously bad
* then we'll bail out.
*/
error = xfs_alloc_read_agfl(mp, sc->tp, sc->sa.agno, &agfl_bp);
if (error)
return error;
/*
* Spot-check the AGFL blocks; if they're obviously corrupt then
* there's nothing we can do but bail out.
*/
error = xfs_agfl_walk(sc->mp, XFS_BUF_TO_AGF(agf_bp), agfl_bp,
xrep_agf_check_agfl_block, sc);
if (error)
return error;
/*
* Find the AGF btree roots. This is also a chicken-and-egg situation;
* see the function for more details.
*/
error = xrep_agf_find_btrees(sc, agf_bp, fab, agfl_bp);
if (error)
return error;
/* Start rewriting the header and implant the btrees we found. */
xrep_agf_init_header(sc, agf_bp, &old_agf);
xrep_agf_set_roots(sc, agf, fab);
error = xrep_agf_calc_from_btrees(sc, agf_bp);
if (error)
goto out_revert;
/* Commit the changes and reinitialize incore state. */
return xrep_agf_commit_new(sc, agf_bp);
out_revert:
/* Mark the incore AGF state stale and revert the AGF. */
sc->sa.pag->pagf_init = 0;
memcpy(agf, &old_agf, sizeof(old_agf));
return error;
}
