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Diffstat (limited to 'fs/xfs/scrub/alloc_repair.c')
-rw-r--r--fs/xfs/scrub/alloc_repair.c761
1 files changed, 761 insertions, 0 deletions
diff --git a/fs/xfs/scrub/alloc_repair.c b/fs/xfs/scrub/alloc_repair.c
new file mode 100644
index 000000000000..0963f18ef32e
--- /dev/null
+++ b/fs/xfs/scrub/alloc_repair.c
@@ -0,0 +1,761 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2021 Oracle. All Rights Reserved.
+ * Author: Darrick J. Wong <djwong@kernel.org>
+ */
+#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_alloc.h"
+#include "xfs_alloc_btree.h"
+#include "xfs_rmap.h"
+#include "xfs_rmap_btree.h"
+#include "xfs_inode.h"
+#include "xfs_refcount.h"
+#include "xfs_extent_busy.h"
+#include "xfs_health.h"
+#include "xfs_bmap.h"
+#include "xfs_ialloc.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/array.h"
+
+/*
+ * Free Space Btree Repair
+ * =======================
+ *
+ * The reverse mappings are supposed to record all space usage for the entire
+ * AG. Therefore, we can recalculate the free extents in an AG by looking for
+ * gaps in the physical extents recorded in the rmapbt. On a reflink
+ * filesystem this is a little more tricky in that we have to be aware that
+ * the rmap records are allowed to overlap.
+ *
+ * We derive which blocks belonged to the old bnobt/cntbt by recording all the
+ * OWN_AG extents and subtracting out the blocks owned by all other OWN_AG
+ * metadata: the rmapbt blocks visited while iterating the reverse mappings
+ * and the AGFL blocks.
+ *
+ * Once we have both of those pieces, we can reconstruct the bnobt and cntbt
+ * by blowing out the free block state and freeing all the extents that we
+ * found. This adds the requirement that we can't have any busy extents in
+ * the AG because the busy code cannot handle duplicate records.
+ *
+ * Note that we can only rebuild both free space btrees at the same time
+ * because the regular extent freeing infrastructure loads both btrees at the
+ * same time.
+ *
+ * We use the prefix 'xrep_abt' here because we regenerate both free space
+ * allocation btrees at the same time.
+ */
+
+struct xrep_abt {
+ /* Blocks owned by the rmapbt or the agfl. */
+ struct xbitmap not_allocbt_blocks;
+
+ /* All OWN_AG blocks. */
+ struct xbitmap old_allocbt_blocks;
+
+ /*
+ * New bnobt information. All btree block reservations are added to
+ * the reservation list in new_bnobt_info.
+ */
+ struct xrep_newbt new_bnobt_info;
+ struct xfs_btree_bload bno_bload;
+
+ /* new cntbt information */
+ struct xrep_newbt new_cntbt_info;
+ struct xfs_btree_bload cnt_bload;
+
+ /* Free space extents. */
+ struct xfbma *free_records;
+
+ struct xfs_scrub *sc;
+
+ /* Number of non-null records in @free_records. */
+ uint64_t nr_real_records;
+
+ /* get_record()'s position in the free space record array. */
+ uint64_t iter;
+
+ /*
+ * Next block we anticipate seeing in the rmap records. If the next
+ * rmap record is greater than next_bno, we have found unused space.
+ */
+ xfs_agblock_t next_bno;
+
+ /* Number of free blocks in this AG. */
+ xfs_agblock_t nr_blocks;
+
+ /* Longest free extent we found in the AG. */
+ xfs_agblock_t longest;
+};
+
+/* Check for any obvious conflicts in the free extent. */
+STATIC int
+xrep_abt_check_free_ext(
+ struct xfs_scrub *sc,
+ const struct xfs_alloc_rec_incore *rec)
+{
+ bool has_inodes, shared;
+ int error;
+
+ /* Must be within the AG and not static data. */
+ if (!xfs_verify_agbext(sc->mp, sc->sa.agno, rec->ar_startblock,
+ rec->ar_blockcount))
+ return -EFSCORRUPTED;
+
+ /* Must not be an inode chunk. */
+ error = xfs_ialloc_has_inodes_at_extent(sc->sa.ino_cur,
+ rec->ar_startblock, rec->ar_blockcount, &has_inodes);
+ if (error)
+ return error;
+ if (has_inodes)
+ return -EFSCORRUPTED;
+
+ /* Must not be shared or CoW staging. */
+ if (sc->sa.refc_cur) {
+ error = xfs_refcount_has_record(sc->sa.refc_cur,
+ rec->ar_startblock, rec->ar_blockcount,
+ &shared);
+ if (error)
+ return error;
+ if (shared)
+ return -EFSCORRUPTED;
+ }
+
+ return 0;
+}
+
+/*
+ * Stash a free space record for all the space since the last bno we found
+ * all the way up to @end.
+ */
+static int
+xrep_abt_stash(
+ struct xrep_abt *ra,
+ xfs_agblock_t end)
+{
+ struct xfs_alloc_rec_incore arec = {
+ .ar_startblock = ra->next_bno,
+ .ar_blockcount = end - ra->next_bno,
+ };
+ struct xfs_scrub *sc = ra->sc;
+ int error = 0;
+
+ if (xchk_should_terminate(sc, &error))
+ return error;
+
+ error = xrep_abt_check_free_ext(ra->sc, &arec);
+ if (error)
+ return error;
+
+ trace_xrep_abt_found(sc->mp, sc->sa.agno, &arec);
+
+ error = xfbma_append(ra->free_records, &arec);
+ if (error)
+ return error;
+
+ ra->nr_blocks += arec.ar_blockcount;
+ return 0;
+}
+
+/* Record extents that aren't in use from gaps in the rmap records. */
+STATIC int
+xrep_abt_walk_rmap(
+ struct xfs_btree_cur *cur,
+ struct xfs_rmap_irec *rec,
+ void *priv)
+{
+ struct xrep_abt *ra = priv;
+ xfs_fsblock_t fsb;
+ int 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_ag.agno,
+ rec->rm_startblock);
+ error = xbitmap_set(&ra->old_allocbt_blocks, fsb,
+ rec->rm_blockcount);
+ if (error)
+ return error;
+ }
+
+ /* ...and all the rmapbt blocks... */
+ error = xbitmap_set_btcur_path(&ra->not_allocbt_blocks, cur);
+ if (error)
+ return error;
+
+ /* ...and all the free space. */
+ if (rec->rm_startblock > ra->next_bno) {
+ error = xrep_abt_stash(ra, rec->rm_startblock);
+ if (error)
+ return error;
+ }
+
+ /*
+ * rmap records can overlap on reflink filesystems, so project next_bno
+ * as far out into the AG space as we currently know about.
+ */
+ ra->next_bno = max_t(xfs_agblock_t, ra->next_bno,
+ rec->rm_startblock + rec->rm_blockcount);
+ return 0;
+}
+
+/* Collect an AGFL block for the not-to-release list. */
+static int
+xrep_abt_walk_agfl(
+ struct xfs_mount *mp,
+ xfs_agblock_t bno,
+ void *priv)
+{
+ struct xrep_abt *ra = priv;
+ xfs_fsblock_t fsb;
+
+ fsb = XFS_AGB_TO_FSB(mp, ra->sc->sa.agno, bno);
+ return xbitmap_set(&ra->not_allocbt_blocks, fsb, 1);
+}
+
+/*
+ * Compare two free space extents by block number. We want to sort by block
+ * number.
+ */
+static int
+xrep_bnobt_extent_cmp(
+ const void *a,
+ const void *b)
+{
+ const struct xfs_alloc_rec_incore *ap = a;
+ const struct xfs_alloc_rec_incore *bp = b;
+
+ if (ap->ar_startblock > bp->ar_startblock)
+ return 1;
+ else if (ap->ar_startblock < bp->ar_startblock)
+ return -1;
+ return 0;
+}
+
+/*
+ * Compare two free space extents by length and then block number. We want
+ * to sort first in order of decreasing length and then in increasing block
+ * number.
+ */
+static int
+xrep_cntbt_extent_cmp(
+ const void *a,
+ const void *b)
+{
+ const struct xfs_alloc_rec_incore *ap = a;
+ const struct xfs_alloc_rec_incore *bp = b;
+
+ if (ap->ar_blockcount > bp->ar_blockcount)
+ return 1;
+ else if (ap->ar_blockcount < bp->ar_blockcount)
+ return -1;
+ return xrep_bnobt_extent_cmp(a, b);
+}
+
+/*
+ * Iterate all reverse mappings to find (1) the gaps between rmap records (all
+ * unowned space), (2) the OWN_AG extents (which encompass the free space
+ * btrees, the rmapbt, and the agfl), (3) the rmapbt blocks, and (4) the AGFL
+ * blocks. The free space is (1) + (2) - (3) - (4).
+ */
+STATIC int
+xrep_abt_find_freespace(
+ struct xrep_abt *ra)
+{
+ struct xfs_scrub *sc = ra->sc;
+ struct xfs_mount *mp = sc->mp;
+ struct xfs_agf *agf = sc->sa.agf_bp->b_addr;
+ xfs_agblock_t agend;
+ int error;
+
+ xbitmap_init(&ra->not_allocbt_blocks);
+
+ xrep_ag_btcur_init(sc, &sc->sa);
+
+ /*
+ * Iterate all the reverse mappings to find gaps in the physical
+ * mappings, all the OWN_AG blocks, and all the rmapbt extents.
+ */
+ error = xfs_rmap_query_all(sc->sa.rmap_cur, xrep_abt_walk_rmap, ra);
+ if (error)
+ goto err;
+
+ /* Insert a record for space between the last rmap and EOAG. */
+ agend = be32_to_cpu(agf->agf_length);
+ if (ra->next_bno < agend) {
+ error = xrep_abt_stash(ra, agend);
+ if (error)
+ goto err;
+ }
+
+ /* Collect all the AGFL blocks. */
+ error = xfs_agfl_walk(mp, agf, sc->sa.agfl_bp, xrep_abt_walk_agfl, ra);
+ if (error)
+ goto err;
+
+ /* Compute the old bnobt/cntbt blocks. */
+ xbitmap_disunion(&ra->old_allocbt_blocks, &ra->not_allocbt_blocks);
+
+ ra->nr_real_records = xfbma_length(ra->free_records);
+err:
+ xchk_ag_btcur_free(&sc->sa);
+ xbitmap_destroy(&ra->not_allocbt_blocks);
+ return error;
+}
+
+/*
+ * We're going to use the observed free space records to reserve blocks for the
+ * new free space btrees, so we play an iterative game where we try to converge
+ * on the number of blocks we need:
+ *
+ * 1. Estimate how many blocks we'll need to store the records.
+ * 2. If the first free record has more blocks than we need, we're done.
+ * We will have to re-sort the records prior to building the cntbt.
+ * 3. If that record has exactly the number of blocks we need, null out the
+ * record. We're done.
+ * 4. Otherwise, we still need more blocks. Null out the record, subtract its
+ * length from the number of blocks we need, and go back to step 1.
+ *
+ * Fortunately, we don't have to do any transaction work to play this game, so
+ * we don't have to tear down the staging cursors.
+ */
+STATIC int
+xrep_abt_reserve_space(
+ struct xrep_abt *ra,
+ struct xfs_btree_cur *bno_cur,
+ struct xfs_btree_cur *cnt_cur,
+ bool *needs_sort)
+{
+ struct xfs_scrub *sc = ra->sc;
+ uint64_t record_nr = xfbma_length(ra->free_records) - 1;
+ unsigned int allocated = 0;
+ int error = 0;
+
+ *needs_sort = false;
+ do {
+ struct xfs_alloc_rec_incore arec;
+ xfs_fsblock_t fsbno;
+ uint64_t required;
+ unsigned int desired;
+ unsigned int len;
+
+ /* Compute how many blocks we'll need. */
+ error = xfs_btree_bload_compute_geometry(cnt_cur,
+ &ra->cnt_bload, ra->nr_real_records);
+ if (error)
+ break;
+
+ error = xfs_btree_bload_compute_geometry(bno_cur,
+ &ra->bno_bload, ra->nr_real_records);
+ if (error)
+ break;
+
+ /* How many btree blocks do we need to store all records? */
+ required = ra->cnt_bload.nr_blocks + ra->bno_bload.nr_blocks;
+ ASSERT(required < INT_MAX);
+
+ /* If we've reserved enough blocks, we're done. */
+ if (allocated >= required)
+ break;
+
+ desired = required - allocated;
+
+ /* We need space but there's none left; bye! */
+ if (ra->nr_real_records == 0) {
+ error = -ENOSPC;
+ break;
+ }
+
+ /* Grab the first record from the list. */
+ error = xfbma_get(ra->free_records, record_nr, &arec);
+ if (error)
+ break;
+
+ ASSERT(arec.ar_blockcount <= UINT_MAX);
+ len = min_t(unsigned int, arec.ar_blockcount, desired);
+ fsbno = XFS_AGB_TO_FSB(sc->mp, sc->sa.agno, arec.ar_startblock);
+ error = xrep_newbt_add_blocks(&ra->new_bnobt_info, fsbno, len);
+ if (error)
+ break;
+ allocated += len;
+ ra->nr_blocks -= len;
+
+ if (arec.ar_blockcount > desired) {
+ /*
+ * Record has more space than we need. The number of
+ * free records doesn't change, so shrink the free
+ * record, inform the caller that we've broken the sort
+ * order of the records, and exit.
+ */
+ arec.ar_startblock += desired;
+ arec.ar_blockcount -= desired;
+ error = xfbma_set(ra->free_records, record_nr, &arec);
+ if (error)
+ break;
+ *needs_sort = true;
+ break;
+ }
+
+ /*
+ * We're going to use up the entire record, so nullify it and
+ * move on to the next one. This changes the number of free
+ * records, so we must go around the loop once more to re-run
+ * _bload_init.
+ */
+ error = xfbma_nullify(ra->free_records, record_nr);
+ if (error)
+ break;
+ ra->nr_real_records--;
+ record_nr--;
+ } while (1);
+
+ return error;
+}
+
+/*
+ * Deal with all the space we reserved. Blocks that were allocated for the
+ * free space btrees need to have a (deferred) rmap added for the OWN_AG
+ * allocation, and blocks that didn't get used can be freed via the usual
+ * (deferred) means.
+ */
+STATIC void
+xrep_abt_dispose_reservations(
+ struct xrep_abt *ra,
+ int error)
+{
+ struct xrep_newbt_resv *resv, *n;
+ struct xfs_scrub *sc = ra->sc;
+
+ if (error)
+ goto junkit;
+
+ for_each_xrep_newbt_reservation(&ra->new_bnobt_info, resv, n) {
+ /* Add a deferred rmap for each extent we used. */
+ if (resv->used > 0)
+ xfs_rmap_alloc_extent(sc->tp,
+ XFS_FSB_TO_AGNO(sc->mp, resv->fsbno),
+ XFS_FSB_TO_AGBNO(sc->mp, resv->fsbno),
+ resv->used, XFS_RMAP_OWN_AG);
+
+ /*
+ * Add a deferred free for each block we didn't use and now
+ * have to add to the free space since the new btrees are
+ * online.
+ */
+ if (resv->used < resv->len)
+ __xfs_bmap_add_free(sc->tp, resv->fsbno + resv->used,
+ resv->len - resv->used, NULL, true);
+ }
+
+junkit:
+ for_each_xrep_newbt_reservation(&ra->new_bnobt_info, resv, n) {
+ list_del(&resv->list);
+ kmem_free(resv);
+ }
+
+ xrep_newbt_destroy(&ra->new_bnobt_info, error);
+ xrep_newbt_destroy(&ra->new_cntbt_info, error);
+}
+
+/* Retrieve free space data for bulk load. */
+STATIC int
+xrep_abt_get_record(
+ struct xfs_btree_cur *cur,
+ void *priv)
+{
+ struct xfs_alloc_rec_incore *arec = &cur->bc_rec.a;
+ struct xrep_abt *ra = priv;
+ int error;
+
+ error = xfbma_iter_get(ra->free_records, &ra->iter, arec);
+ if (error)
+ return error;
+
+ ra->longest = max(ra->longest, arec->ar_blockcount);
+ return 0;
+}
+
+/* Feed one of the new btree blocks to the bulk loader. */
+STATIC int
+xrep_abt_claim_block(
+ struct xfs_btree_cur *cur,
+ union xfs_btree_ptr *ptr,
+ void *priv)
+{
+ struct xrep_abt *ra = priv;
+
+ return xrep_newbt_claim_block(cur, &ra->new_bnobt_info, ptr);
+}
+
+/*
+ * Reset the AGF counters to reflect the free space btrees that we just
+ * rebuilt, then reinitialize the per-AG data.
+ */
+STATIC int
+xrep_abt_reset_counters(
+ struct xrep_abt *ra,
+ unsigned int freesp_btreeblks)
+{
+ struct xfs_scrub *sc = ra->sc;
+ struct xfs_perag *pag = sc->sa.pag;
+ struct xfs_agf *agf = sc->sa.agf_bp->b_addr;
+ struct xfs_buf *bp;
+
+ /*
+ * Mark the pagf information stale and use the accessor function to
+ * forcibly reload it from the values we just logged. We still own the
+ * AGF buffer so we can safely ignore bp.
+ */
+ ASSERT(pag->pagf_init);
+ pag->pagf_init = 0;
+
+ agf->agf_btreeblks = cpu_to_be32(freesp_btreeblks +
+ (be32_to_cpu(agf->agf_rmap_blocks) - 1));
+ agf->agf_freeblks = cpu_to_be32(ra->nr_blocks);
+ agf->agf_longest = cpu_to_be32(ra->longest);
+ xfs_alloc_log_agf(sc->tp, sc->sa.agf_bp, XFS_AGF_BTREEBLKS |
+ XFS_AGF_LONGEST |
+ XFS_AGF_FREEBLKS);
+
+ return xfs_alloc_read_agf(sc->mp, sc->tp, sc->sa.agno, 0, &bp);
+}
+
+static void
+xrep_abt_init_bload(
+ struct xrep_abt *ra,
+ struct xfs_btree_bload *bload)
+{
+ bload->get_record = xrep_abt_get_record;
+ bload->claim_block = xrep_abt_claim_block;
+
+ xrep_bload_estimate_slack(ra->sc, bload);
+}
+
+/*
+ * Use the collected free space information to stage new free space btrees.
+ * If this is successful we'll return with the new btree root
+ * information logged to the repair transaction but not yet committed.
+ */
+STATIC int
+xrep_abt_build_new_trees(
+ struct xrep_abt *ra)
+{
+ struct xfs_scrub *sc = ra->sc;
+ struct xfs_btree_cur *bno_cur;
+ struct xfs_btree_cur *cnt_cur;
+ bool needs_sort;
+ int error;
+
+ xrep_abt_init_bload(ra, &ra->bno_bload);
+ xrep_abt_init_bload(ra, &ra->cnt_bload);
+
+ /*
+ * Sort the free extents by length so that we can set up the free space
+ * btrees in as few extents as possible. This reduces the amount of
+ * deferred rmap / free work we have to do at the end.
+ */
+ error = xfbma_sort(ra->free_records, xrep_cntbt_extent_cmp);
+ if (error)
+ return error;
+
+ /*
+ * Prepare to construct the new btree by reserving disk space for the
+ * new btree and setting up all the accounting information we'll need
+ * to root the new btree while it's under construction and before we
+ * attach it to the AG header.
+ */
+ xrep_newbt_init_bare(&ra->new_bnobt_info, sc);
+ xrep_newbt_init_bare(&ra->new_cntbt_info, sc);
+
+ /* Allocate cursors for the staged btrees. */
+ bno_cur = xfs_allocbt_stage_cursor(sc->mp, &ra->new_bnobt_info.afake,
+ sc->sa.agno, XFS_BTNUM_BNO);
+ cnt_cur = xfs_allocbt_stage_cursor(sc->mp, &ra->new_cntbt_info.afake,
+ sc->sa.agno, XFS_BTNUM_CNT);
+
+ /* Reserve the space we'll need for the new btrees. */
+ error = xrep_abt_reserve_space(ra, bno_cur, cnt_cur, &needs_sort);
+ if (error)
+ goto out_cur;
+
+ /*
+ * If we need to re-sort the free extents by length, do so so that we
+ * can put the records into the cntbt in the correct order.
+ */
+ if (needs_sort) {
+ error = xfbma_sort(ra->free_records, xrep_cntbt_extent_cmp);
+ if (error)
+ goto out_cur;
+ }
+
+ /* Load the free space by length tree. */
+ ra->iter = 0;
+ ra->longest = 0;
+ error = xfs_btree_bload(cnt_cur, &ra->cnt_bload, ra);
+ if (error)
+ goto out_cur;
+
+ /* Re-sort the free extents by block number so so that we can put the
+ * records into the bnobt in the correct order.
+ */
+ error = xfbma_sort(ra->free_records, xrep_bnobt_extent_cmp);
+ if (error)
+ goto out_cur;
+
+ /* Load the free space by block number tree. */
+ ra->iter = 0;
+ error = xfs_btree_bload(bno_cur, &ra->bno_bload, ra);
+ if (error)
+ goto out_cur;
+
+ /*
+ * Install the new btrees in the AG header. After this point the old
+ * btree is no longer accessible and the new tree is live.
+ *
+ * Note: We re-read the AGF here to ensure the buffer type is set
+ * properly. Since we built a new tree without attaching to the AGF
+ * buffer, the buffer item may have fallen off the buffer. This ought
+ * to succeed since the AGF is held across transaction rolls.
+ */
+ error = xfs_read_agf(sc->mp, sc->tp, sc->sa.agno, 0, &sc->sa.agf_bp);
+ if (error)
+ goto out_cur;
+
+ /* Commit our new btrees. */
+ xfs_allocbt_commit_staged_btree(bno_cur, sc->tp, sc->sa.agf_bp);
+ xfs_btree_del_cursor(bno_cur, 0);
+ xfs_allocbt_commit_staged_btree(cnt_cur, sc->tp, sc->sa.agf_bp);
+ xfs_btree_del_cursor(cnt_cur, 0);
+
+ /* Reset the AGF counters now that we've changed the btree shape. */
+ error = xrep_abt_reset_counters(ra, (ra->bno_bload.nr_blocks - 1) +
+ (ra->cnt_bload.nr_blocks - 1));
+ if (error)
+ goto out_newbt;
+
+ /* Dispose of any unused blocks and the accounting information. */
+ xrep_abt_dispose_reservations(ra, error);
+
+ return xrep_roll_ag_trans(sc);
+
+out_cur:
+ xfs_btree_del_cursor(cnt_cur, error);
+ xfs_btree_del_cursor(bno_cur, error);
+out_newbt:
+ xrep_abt_dispose_reservations(ra, error);
+ return error;
+}
+
+/*
+ * Now that we've logged the roots of the new btrees, invalidate all of the
+ * old blocks and free them.
+ */
+STATIC int
+xrep_abt_remove_old_trees(
+ struct xrep_abt *ra)
+{
+ /* Free the old inode btree blocks if they're not in use. */
+ return xrep_reap_extents(ra->sc, &ra->old_allocbt_blocks,
+ &XFS_RMAP_OINFO_AG, XFS_AG_RESV_IGNORE);
+}
+
+/* Repair the freespace btrees for some AG. */
+int
+xrep_allocbt(
+ struct xfs_scrub *sc)
+{
+ struct xrep_abt *ra;
+ struct xfs_mount *mp = sc->mp;
+ int error;
+
+ /* We require the rmapbt to rebuild anything. */
+ if (!xfs_sb_version_hasrmapbt(&mp->m_sb))
+ return -EOPNOTSUPP;
+
+ ra = kmem_zalloc(sizeof(struct xrep_abt), KM_NOFS | KM_MAYFAIL);
+ if (!ra)
+ return -ENOMEM;
+ ra->sc = sc;
+
+ /* We rebuild both data structures. */
+ sc->sick_mask = XFS_SICK_AG_BNOBT | XFS_SICK_AG_CNTBT;
+
+ xchk_perag_get(sc->mp, &sc->sa);
+
+ /*
+ * Make sure the busy extent list is clear because we can't put
+ * extents on there twice.
+ */
+ if (!xfs_extent_busy_list_empty(sc->sa.pag))
+ return -EDEADLOCK;
+
+ /* Set up some storage */
+ ra->free_records = xfbma_init("freesp extents",
+ sizeof(struct xfs_alloc_rec_incore));
+ if (IS_ERR(ra->free_records)) {
+ error = PTR_ERR(ra->free_records);
+ goto out_ra;
+ }
+
+ /* Collect the free space data and find the old btree blocks. */
+ xbitmap_init(&ra->old_allocbt_blocks);
+ error = xrep_abt_find_freespace(ra);
+ if (error)
+ goto out_bitmap;
+
+ /* Rebuild the free space information. */
+ error = xrep_abt_build_new_trees(ra);
+ if (error)
+ goto out_bitmap;
+
+ /* Kill the old trees. */
+ error = xrep_abt_remove_old_trees(ra);
+
+out_bitmap:
+ xbitmap_destroy(&ra->old_allocbt_blocks);
+ xfbma_destroy(ra->free_records);
+out_ra:
+ kmem_free(ra);
+ return error;
+}
+
+/* Make sure both btrees are ok after we've rebuilt them. */
+int
+xrep_revalidate_allocbt(
+ struct xfs_scrub *sc)
+{
+ __u32 old_type = sc->sm->sm_type;
+ int error;
+
+ /*
+ * We must update sm_type temporarily so that the tree-to-tree cross
+ * reference checks will work in the correct direction, and also so
+ * that tracing will report correctly if there are more errors.
+ */
+ sc->sm->sm_type = XFS_SCRUB_TYPE_BNOBT;
+ error = xchk_bnobt(sc);
+ if (error)
+ goto out;
+
+ sc->sm->sm_type = XFS_SCRUB_TYPE_CNTBT;
+ error = xchk_cntbt(sc);
+out:
+ sc->sm->sm_type = old_type;
+ return error;
+}