diff options
Diffstat (limited to 'fs/xfs/scrub/agheader_repair.c')
| -rw-r--r-- | fs/xfs/scrub/agheader_repair.c | 933 |
1 files changed, 933 insertions, 0 deletions
diff --git a/fs/xfs/scrub/agheader_repair.c b/fs/xfs/scrub/agheader_repair.c new file mode 100644 index 000000000..f7568a4b5 --- /dev/null +++ b/fs/xfs/scrub/agheader_repair.c @@ -0,0 +1,933 @@ +// 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; +} + +/* AGFL */ + +struct xrep_agfl { + /* Bitmap of other OWN_AG metadata blocks. */ + struct xfs_bitmap agmetablocks; + + /* Bitmap of free space. */ + struct xfs_bitmap *freesp; + + struct xfs_scrub *sc; +}; + +/* Record all OWN_AG (free space btree) information from the rmap data. */ +STATIC int +xrep_agfl_walk_rmap( + struct xfs_btree_cur *cur, + struct xfs_rmap_irec *rec, + void *priv) +{ + struct xrep_agfl *ra = priv; + xfs_fsblock_t fsb; + int error = 0; + + if (xchk_should_terminate(ra->sc, &error)) + return error; + + /* Record all the OWN_AG blocks. */ + if (rec->rm_owner == XFS_RMAP_OWN_AG) { + fsb = XFS_AGB_TO_FSB(cur->bc_mp, cur->bc_private.a.agno, + rec->rm_startblock); + error = xfs_bitmap_set(ra->freesp, fsb, rec->rm_blockcount); + if (error) + return error; + } + + return xfs_bitmap_set_btcur_path(&ra->agmetablocks, cur); +} + +/* + * Map out all the non-AGFL OWN_AG space in this AG so that we can deduce + * which blocks belong to the AGFL. + * + * Compute the set of old AGFL blocks by subtracting from the list of OWN_AG + * blocks the list of blocks owned by all other OWN_AG metadata (bnobt, cntbt, + * rmapbt). These are the old AGFL blocks, so return that list and the number + * of blocks we're actually going to put back on the AGFL. + */ +STATIC int +xrep_agfl_collect_blocks( + struct xfs_scrub *sc, + struct xfs_buf *agf_bp, + struct xfs_bitmap *agfl_extents, + xfs_agblock_t *flcount) +{ + struct xrep_agfl ra; + struct xfs_mount *mp = sc->mp; + struct xfs_btree_cur *cur; + struct xfs_bitmap_range *br; + struct xfs_bitmap_range *n; + int error; + + ra.sc = sc; + ra.freesp = agfl_extents; + xfs_bitmap_init(&ra.agmetablocks); + + /* Find all space used by the free space btrees & rmapbt. */ + cur = xfs_rmapbt_init_cursor(mp, sc->tp, agf_bp, sc->sa.agno); + error = xfs_rmap_query_all(cur, xrep_agfl_walk_rmap, &ra); + if (error) + goto err; + xfs_btree_del_cursor(cur, error); + + /* Find all blocks currently being used by the bnobt. */ + cur = xfs_allocbt_init_cursor(mp, sc->tp, agf_bp, sc->sa.agno, + XFS_BTNUM_BNO); + error = xfs_bitmap_set_btblocks(&ra.agmetablocks, cur); + if (error) + goto err; + xfs_btree_del_cursor(cur, error); + + /* Find all blocks currently being used by the cntbt. */ + cur = xfs_allocbt_init_cursor(mp, sc->tp, agf_bp, sc->sa.agno, + XFS_BTNUM_CNT); + error = xfs_bitmap_set_btblocks(&ra.agmetablocks, cur); + if (error) + goto err; + + xfs_btree_del_cursor(cur, error); + + /* + * Drop the freesp meta blocks that are in use by btrees. + * The remaining blocks /should/ be AGFL blocks. + */ + error = xfs_bitmap_disunion(agfl_extents, &ra.agmetablocks); + xfs_bitmap_destroy(&ra.agmetablocks); + if (error) + return error; + + /* + * Calculate the new AGFL size. If we found more blocks than fit in + * the AGFL we'll free them later. + */ + *flcount = 0; + for_each_xfs_bitmap_extent(br, n, agfl_extents) { + *flcount += br->len; + if (*flcount > xfs_agfl_size(mp)) + break; + } + if (*flcount > xfs_agfl_size(mp)) + *flcount = xfs_agfl_size(mp); + return 0; + +err: + xfs_bitmap_destroy(&ra.agmetablocks); + xfs_btree_del_cursor(cur, error); + return error; +} + +/* Update the AGF and reset the in-core state. */ +STATIC void +xrep_agfl_update_agf( + struct xfs_scrub *sc, + struct xfs_buf *agf_bp, + xfs_agblock_t flcount) +{ + struct xfs_agf *agf = XFS_BUF_TO_AGF(agf_bp); + + ASSERT(flcount <= xfs_agfl_size(sc->mp)); + + /* Trigger fdblocks recalculation */ + xfs_force_summary_recalc(sc->mp); + + /* Update the AGF counters. */ + if (sc->sa.pag->pagf_init) + sc->sa.pag->pagf_flcount = flcount; + agf->agf_flfirst = cpu_to_be32(0); + agf->agf_flcount = cpu_to_be32(flcount); + agf->agf_fllast = cpu_to_be32(flcount - 1); + + xfs_alloc_log_agf(sc->tp, agf_bp, + XFS_AGF_FLFIRST | XFS_AGF_FLLAST | XFS_AGF_FLCOUNT); +} + +/* Write out a totally new AGFL. */ +STATIC void +xrep_agfl_init_header( + struct xfs_scrub *sc, + struct xfs_buf *agfl_bp, + struct xfs_bitmap *agfl_extents, + xfs_agblock_t flcount) +{ + struct xfs_mount *mp = sc->mp; + __be32 *agfl_bno; + struct xfs_bitmap_range *br; + struct xfs_bitmap_range *n; + struct xfs_agfl *agfl; + xfs_agblock_t agbno; + unsigned int fl_off; + + ASSERT(flcount <= xfs_agfl_size(mp)); + + /* + * Start rewriting the header by setting the bno[] array to + * NULLAGBLOCK, then setting AGFL header fields. + */ + agfl = XFS_BUF_TO_AGFL(agfl_bp); + memset(agfl, 0xFF, BBTOB(agfl_bp->b_length)); + agfl->agfl_magicnum = cpu_to_be32(XFS_AGFL_MAGIC); + agfl->agfl_seqno = cpu_to_be32(sc->sa.agno); + uuid_copy(&agfl->agfl_uuid, &mp->m_sb.sb_meta_uuid); + + /* + * Fill the AGFL with the remaining blocks. If agfl_extents has more + * blocks than fit in the AGFL, they will be freed in a subsequent + * step. + */ + fl_off = 0; + agfl_bno = XFS_BUF_TO_AGFL_BNO(mp, agfl_bp); + for_each_xfs_bitmap_extent(br, n, agfl_extents) { + agbno = XFS_FSB_TO_AGBNO(mp, br->start); + + trace_xrep_agfl_insert(mp, sc->sa.agno, agbno, br->len); + + while (br->len > 0 && fl_off < flcount) { + agfl_bno[fl_off] = cpu_to_be32(agbno); + fl_off++; + agbno++; + + /* + * We've now used br->start by putting it in the AGFL, + * so bump br so that we don't reap the block later. + */ + br->start++; + br->len--; + } + + if (br->len) + break; + list_del(&br->list); + kmem_free(br); + } + + /* Write new AGFL to disk. */ + xfs_trans_buf_set_type(sc->tp, agfl_bp, XFS_BLFT_AGFL_BUF); + xfs_trans_log_buf(sc->tp, agfl_bp, 0, BBTOB(agfl_bp->b_length) - 1); +} + +/* Repair the AGFL. */ +int +xrep_agfl( + struct xfs_scrub *sc) +{ + struct xfs_owner_info oinfo; + struct xfs_bitmap agfl_extents; + struct xfs_mount *mp = sc->mp; + struct xfs_buf *agf_bp; + struct xfs_buf *agfl_bp; + xfs_agblock_t flcount; + 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); + xfs_bitmap_init(&agfl_extents); + + /* + * Read the AGF so that we can query the rmapbt. We hope that there's + * nothing wrong with the AGF, but all the AG header repair functions + * have this chicken-and-egg problem. + */ + error = xfs_alloc_read_agf(mp, sc->tp, sc->sa.agno, 0, &agf_bp); + if (error) + return error; + if (!agf_bp) + return -ENOMEM; + + /* + * Make sure we have the AGFL buffer, as scrub might have decided it + * was corrupt after xfs_alloc_read_agfl failed with -EFSCORRUPTED. + */ + error = xfs_trans_read_buf(mp, sc->tp, mp->m_ddev_targp, + XFS_AG_DADDR(mp, sc->sa.agno, XFS_AGFL_DADDR(mp)), + XFS_FSS_TO_BB(mp, 1), 0, &agfl_bp, NULL); + if (error) + return error; + agfl_bp->b_ops = &xfs_agfl_buf_ops; + + /* Gather all the extents we're going to put on the new AGFL. */ + error = xrep_agfl_collect_blocks(sc, agf_bp, &agfl_extents, &flcount); + if (error) + goto err; + + /* + * Update AGF and AGFL. We reset the global free block counter when + * we adjust the AGF flcount (which can fail) so avoid updating any + * buffers until we know that part works. + */ + xrep_agfl_update_agf(sc, agf_bp, flcount); + xrep_agfl_init_header(sc, agfl_bp, &agfl_extents, flcount); + + /* + * Ok, the AGFL should be ready to go now. Roll the transaction to + * make the new AGFL permanent before we start using it to return + * freespace overflow to the freespace btrees. + */ + sc->sa.agf_bp = agf_bp; + sc->sa.agfl_bp = agfl_bp; + error = xrep_roll_ag_trans(sc); + if (error) + goto err; + + /* Dump any AGFL overflow. */ + xfs_rmap_ag_owner(&oinfo, XFS_RMAP_OWN_AG); + return xrep_reap_extents(sc, &agfl_extents, &oinfo, XFS_AG_RESV_AGFL); +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; +} |