xfs: repair the AGI

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

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
This commit is contained in:
Darrick J. Wong 2018-08-09 22:43:04 -07:00
parent 0e93d3f43e
commit 13942aa94a
3 changed files with 220 additions and 1 deletions

View File

@ -714,3 +714,220 @@ err:
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;
}

View File

@ -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 */

View File

@ -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,