blob: d421b253923edc25981e92d5835a705cddf309a0 [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright (C) 2018-2023 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_btree_staging.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 "xfs_ag.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/agb_bitmap.h"
#include "scrub/xfile.h"
#include "scrub/xfarray.h"
#include "scrub/newbt.h"
#include "scrub/reap.h"
/*
* Free Space Btree Repair
* =======================
*
* The reverse mappings are supposed to record all space usage for the entire
* AG. Therefore, we can recreate the free extent records in an AG by looking
* for gaps in the physical extents recorded in the rmapbt. These records are
* staged in @free_records. Identifying the gaps is more difficult on a
* reflink filesystem because rmap records are allowed to overlap.
*
* Because the final step of building a new index is to free the space used by
* the old index, repair needs to find that space. Unfortunately, all
* structures that live in the free space (bnobt, cntbt, rmapbt, agfl) share
* the same rmapbt owner code (OWN_AG), so this is not straightforward.
*
* The scan of the reverse mapping information records the space used by OWN_AG
* in @old_allocbt_blocks, which (at this stage) is somewhat misnamed. While
* walking the rmapbt records, we create a second bitmap @not_allocbt_blocks to
* record all visited rmap btree blocks and all blocks owned by the AGFL.
*
* After that is where the definitions of old_allocbt_blocks shifts. This
* expression identifies possible former bnobt/cntbt blocks:
*
* (OWN_AG blocks) & ~(rmapbt blocks | agfl blocks);
*
* Substituting from above definitions, that becomes:
*
* old_allocbt_blocks & ~not_allocbt_blocks
*
* The OWN_AG bitmap itself isn't needed after this point, so what we really do
* instead is:
*
* old_allocbt_blocks &= ~not_allocbt_blocks;
*
* After this point, @old_allocbt_blocks is a bitmap of alleged former
* bnobt/cntbt blocks. The xagb_bitmap_disunion operation modifies its first
* parameter in place to avoid copying records around.
*
* Next, some of the space described by @free_records are diverted to the newbt
* reservation and used to format new btree blocks. The remaining records are
* written to the new btree indices. We reconstruct both bnobt and cntbt at
* the same time since we've already done all the work.
*
* 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 xagb_bitmap not_allocbt_blocks;
/* All OWN_AG blocks. */
struct xagb_bitmap old_allocbt_blocks;
/*
* New bnobt information. All btree block reservations are added to
* the reservation list in new_bnobt.
*/
struct xrep_newbt new_bnobt;
/* new cntbt information */
struct xrep_newbt new_cntbt;
/* Free space extents. */
struct xfarray *free_records;
struct xfs_scrub *sc;
/* Number of non-null records in @free_records. */
uint64_t nr_real_records;
/* get_records()'s position in the free space record array. */
xfarray_idx_t array_cur;
/*
* Next block we anticipate seeing in the rmap records. If the next
* rmap record is greater than next_agbno, we have found unused space.
*/
xfs_agblock_t next_agbno;
/* Number of free blocks in this AG. */
xfs_agblock_t nr_blocks;
/* Longest free extent we found in the AG. */
xfs_agblock_t longest;
};
/* Set up to repair AG free space btrees. */
int
xrep_setup_ag_allocbt(
struct xfs_scrub *sc)
{
unsigned int busy_gen;
/*
* Make sure the busy extent list is clear because we can't put extents
* on there twice.
*/
busy_gen = READ_ONCE(sc->sa.pag->pagb_gen);
if (xfs_extent_busy_list_empty(sc->sa.pag))
return 0;
return xfs_extent_busy_flush(sc->tp, sc->sa.pag, busy_gen, 0);
}
/* 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)
{
enum xbtree_recpacking outcome;
int error;
if (xfs_alloc_check_irec(sc->sa.pag, rec) != NULL)
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, &outcome);
if (error)
return error;
if (outcome != XBTREE_RECPACKING_EMPTY)
return -EFSCORRUPTED;
/* Must not be shared or CoW staging. */
if (sc->sa.refc_cur) {
error = xfs_refcount_has_records(sc->sa.refc_cur,
XFS_REFC_DOMAIN_SHARED, rec->ar_startblock,
rec->ar_blockcount, &outcome);
if (error)
return error;
if (outcome != XBTREE_RECPACKING_EMPTY)
return -EFSCORRUPTED;
error = xfs_refcount_has_records(sc->sa.refc_cur,
XFS_REFC_DOMAIN_COW, rec->ar_startblock,
rec->ar_blockcount, &outcome);
if (error)
return error;
if (outcome != XBTREE_RECPACKING_EMPTY)
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_agbno,
.ar_blockcount = end - ra->next_agbno,
};
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.pag->pag_agno, &arec);
error = xfarray_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,
const struct xfs_rmap_irec *rec,
void *priv)
{
struct xrep_abt *ra = priv;
int error;
/* Record all the OWN_AG blocks... */
if (rec->rm_owner == XFS_RMAP_OWN_AG) {
error = xagb_bitmap_set(&ra->old_allocbt_blocks,
rec->rm_startblock, rec->rm_blockcount);
if (error)
return error;
}
/* ...and all the rmapbt blocks... */
error = xagb_bitmap_set_btcur_path(&ra->not_allocbt_blocks, cur);
if (error)
return error;
/* ...and all the free space. */
if (rec->rm_startblock > ra->next_agbno) {
error = xrep_abt_stash(ra, rec->rm_startblock);
if (error)
return error;
}
/*
* rmap records can overlap on reflink filesystems, so project
* next_agbno as far out into the AG space as we currently know about.
*/
ra->next_agbno = max_t(xfs_agblock_t, ra->next_agbno,
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 agbno,
void *priv)
{
struct xrep_abt *ra = priv;
return xagb_bitmap_set(&ra->not_allocbt_blocks, agbno, 1);
}
/*
* Compare two free space extents by block number. We want to sort in order of
* increasing 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;
}
/*
* Re-sort the free extents by block number so that we can put the records into
* the bnobt in the correct order. Make sure the records do not overlap in
* physical space.
*/
STATIC int
xrep_bnobt_sort_records(
struct xrep_abt *ra)
{
struct xfs_alloc_rec_incore arec;
xfarray_idx_t cur = XFARRAY_CURSOR_INIT;
xfs_agblock_t next_agbno = 0;
int error;
error = xfarray_sort(ra->free_records, xrep_bnobt_extent_cmp, 0);
if (error)
return error;
while ((error = xfarray_iter(ra->free_records, &cur, &arec)) == 1) {
if (arec.ar_startblock < next_agbno)
return -EFSCORRUPTED;
next_agbno = arec.ar_startblock + arec.ar_blockcount;
}
return error;
}
/*
* Compare two free space extents by length and then block number. We want
* to sort first in order of increasing length and then in order of 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);
}
/*
* Sort the free extents by length so so that we can put the records into the
* cntbt in the correct order. Don't let userspace kill us if we're resorting
* after allocating btree blocks.
*/
STATIC int
xrep_cntbt_sort_records(
struct xrep_abt *ra,
bool is_resort)
{
return xfarray_sort(ra->free_records, xrep_cntbt_extent_cmp,
is_resort ? 0 : XFARRAY_SORT_KILLABLE);
}
/*
* 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;
struct xfs_buf *agfl_bp;
xfs_agblock_t agend;
int error;
xagb_bitmap_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_agbno < agend) {
error = xrep_abt_stash(ra, agend);
if (error)
goto err;
}
/* Collect all the AGFL blocks. */
error = xfs_alloc_read_agfl(sc->sa.pag, sc->tp, &agfl_bp);
if (error)
goto err;
error = xfs_agfl_walk(mp, agf, agfl_bp, xrep_abt_walk_agfl, ra);
if (error)
goto err_agfl;
/* Compute the old bnobt/cntbt blocks. */
error = xagb_bitmap_disunion(&ra->old_allocbt_blocks,
&ra->not_allocbt_blocks);
if (error)
goto err_agfl;
ra->nr_real_records = xfarray_length(ra->free_records);
err_agfl:
xfs_trans_brelse(sc->tp, agfl_bp);
err:
xchk_ag_btcur_free(&sc->sa);
xagb_bitmap_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_resort)
{
struct xfs_scrub *sc = ra->sc;
xfarray_idx_t record_nr;
unsigned int allocated = 0;
int error = 0;
record_nr = xfarray_length(ra->free_records) - 1;
do {
struct xfs_alloc_rec_incore arec;
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->new_cntbt.bload, ra->nr_real_records);
if (error)
break;
error = xfs_btree_bload_compute_geometry(bno_cur,
&ra->new_bnobt.bload, ra->nr_real_records);
if (error)
break;
/* How many btree blocks do we need to store all records? */
required = ra->new_bnobt.bload.nr_blocks +
ra->new_cntbt.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 = xfarray_load(ra->free_records, record_nr, &arec);
if (error)
break;
ASSERT(arec.ar_blockcount <= UINT_MAX);
len = min_t(unsigned int, arec.ar_blockcount, desired);
trace_xrep_newbt_alloc_ag_blocks(sc->mp, sc->sa.pag->pag_agno,
arec.ar_startblock, len, XFS_RMAP_OWN_AG);
error = xrep_newbt_add_extent(&ra->new_bnobt, sc->sa.pag,
arec.ar_startblock, 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 the records are no
* longer sorted by length, and exit.
*/
arec.ar_startblock += desired;
arec.ar_blockcount -= desired;
error = xfarray_store(ra->free_records, record_nr,
&arec);
if (error)
break;
*needs_resort = true;
return 0;
}
/*
* We're going to use up the entire record, so unset it and
* move on to the next one. This changes the number of free
* records (but doesn't break the sorting order), so we must
* go around the loop once more to re-run _bload_init.
*/
error = xfarray_unset(ra->free_records, record_nr);
if (error)
break;
ra->nr_real_records--;
record_nr--;
} while (1);
return error;
}
STATIC int
xrep_abt_dispose_one(
struct xrep_abt *ra,
struct xrep_newbt_resv *resv)
{
struct xfs_scrub *sc = ra->sc;
struct xfs_perag *pag = sc->sa.pag;
xfs_agblock_t free_agbno = resv->agbno + resv->used;
xfs_extlen_t free_aglen = resv->len - resv->used;
int error;
ASSERT(pag == resv->pag);
/* Add a deferred rmap for each extent we used. */
if (resv->used > 0)
xfs_rmap_alloc_extent(sc->tp, pag->pag_agno, resv->agbno,
resv->used, XFS_RMAP_OWN_AG);
/*
* For each reserved btree block we didn't use, add it to the free
* space btree. We didn't touch fdblocks when we reserved them, so
* we don't touch it now.
*/
if (free_aglen == 0)
return 0;
trace_xrep_newbt_free_blocks(sc->mp, resv->pag->pag_agno, free_agbno,
free_aglen, ra->new_bnobt.oinfo.oi_owner);
error = __xfs_free_extent(sc->tp, resv->pag, free_agbno, free_aglen,
&ra->new_bnobt.oinfo, XFS_AG_RESV_IGNORE, true);
if (error)
return error;
return xrep_defer_finish(sc);
}
/*
* 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;
if (error)
goto junkit;
list_for_each_entry_safe(resv, n, &ra->new_bnobt.resv_list, list) {
error = xrep_abt_dispose_one(ra, resv);
if (error)
goto junkit;
}
junkit:
list_for_each_entry_safe(resv, n, &ra->new_bnobt.resv_list, list) {
xfs_perag_put(resv->pag);
list_del(&resv->list);
kfree(resv);
}
xrep_newbt_cancel(&ra->new_bnobt);
xrep_newbt_cancel(&ra->new_cntbt);
}
/* Retrieve free space data for bulk load. */
STATIC int
xrep_abt_get_records(
struct xfs_btree_cur *cur,
unsigned int idx,
struct xfs_btree_block *block,
unsigned int nr_wanted,
void *priv)
{
struct xfs_alloc_rec_incore *arec = &cur->bc_rec.a;
struct xrep_abt *ra = priv;
union xfs_btree_rec *block_rec;
unsigned int loaded;
int error;
for (loaded = 0; loaded < nr_wanted; loaded++, idx++) {
error = xfarray_load_next(ra->free_records, &ra->array_cur,
arec);
if (error)
return error;
ra->longest = max(ra->longest, arec->ar_blockcount);
block_rec = xfs_btree_rec_addr(cur, idx, block);
cur->bc_ops->init_rec_from_cur(cur, block_rec);
}
return loaded;
}
/* 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, 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)
{
struct xfs_scrub *sc = ra->sc;
struct xfs_perag *pag = sc->sa.pag;
struct xfs_agf *agf = sc->sa.agf_bp->b_addr;
unsigned int freesp_btreeblks = 0;
/*
* Compute the contribution to agf_btreeblks for the new free space
* btrees. This is the computed btree size minus anything we didn't
* use.
*/
freesp_btreeblks += ra->new_bnobt.bload.nr_blocks - 1;
freesp_btreeblks += ra->new_cntbt.bload.nr_blocks - 1;
freesp_btreeblks -= xrep_newbt_unused_blocks(&ra->new_bnobt);
freesp_btreeblks -= xrep_newbt_unused_blocks(&ra->new_cntbt);
/*
* The AGF header contains extra information related to the free space
* btrees, so we must update those fields here.
*/
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);
/*
* After we commit the new btree to disk, it is possible that the
* process to reap the old btree blocks will race with the AIL trying
* to checkpoint the old btree blocks into the filesystem. If the new
* tree is shorter than the old one, the allocbt write verifier will
* fail and the AIL will shut down the filesystem.
*
* To avoid this, save the old incore btree height values as the alt
* height values before re-initializing the perag info from the updated
* AGF to capture all the new values.
*/
pag->pagf_repair_bno_level = pag->pagf_bno_level;
pag->pagf_repair_cnt_level = pag->pagf_cnt_level;
/* Reinitialize with the values we just logged. */
return xrep_reinit_pagf(sc);
}
/*
* 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;
struct xfs_perag *pag = sc->sa.pag;
bool needs_resort = false;
int error;
/*
* 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 = xrep_cntbt_sort_records(ra, false);
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, sc);
xrep_newbt_init_bare(&ra->new_cntbt, sc);
ra->new_bnobt.bload.get_records = xrep_abt_get_records;
ra->new_cntbt.bload.get_records = xrep_abt_get_records;
ra->new_bnobt.bload.claim_block = xrep_abt_claim_block;
ra->new_cntbt.bload.claim_block = xrep_abt_claim_block;
/* Allocate cursors for the staged btrees. */
bno_cur = xfs_bnobt_init_cursor(sc->mp, NULL, NULL, pag);
xfs_btree_stage_afakeroot(bno_cur, &ra->new_bnobt.afake);
cnt_cur = xfs_cntbt_init_cursor(sc->mp, NULL, NULL, pag);
xfs_btree_stage_afakeroot(cnt_cur, &ra->new_cntbt.afake);
/* Last chance to abort before we start committing fixes. */
if (xchk_should_terminate(sc, &error))
goto err_cur;
/* Reserve the space we'll need for the new btrees. */
error = xrep_abt_reserve_space(ra, bno_cur, cnt_cur, &needs_resort);
if (error)
goto err_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_resort) {
error = xrep_cntbt_sort_records(ra, needs_resort);
if (error)
goto err_cur;
}
/*
* Due to btree slack factors, it's possible for a new btree to be one
* level taller than the old btree. Update the alternate incore btree
* height so that we don't trip the verifiers when writing the new
* btree blocks to disk.
*/
pag->pagf_repair_bno_level = ra->new_bnobt.bload.btree_height;
pag->pagf_repair_cnt_level = ra->new_cntbt.bload.btree_height;
/* Load the free space by length tree. */
ra->array_cur = XFARRAY_CURSOR_INIT;
ra->longest = 0;
error = xfs_btree_bload(cnt_cur, &ra->new_cntbt.bload, ra);
if (error)
goto err_levels;
error = xrep_bnobt_sort_records(ra);
if (error)
return error;
/* Load the free space by block number tree. */
ra->array_cur = XFARRAY_CURSOR_INIT;
error = xfs_btree_bload(bno_cur, &ra->new_bnobt.bload, ra);
if (error)
goto err_levels;
/*
* Install the new btrees in the AG header. After this point the old
* btrees are no longer accessible and the new trees are live.
*/
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);
if (error)
goto err_newbt;
/* Dispose of any unused blocks and the accounting information. */
xrep_abt_dispose_reservations(ra, error);
return xrep_roll_ag_trans(sc);
err_levels:
pag->pagf_repair_bno_level = 0;
pag->pagf_repair_cnt_level = 0;
err_cur:
xfs_btree_del_cursor(cnt_cur, error);
xfs_btree_del_cursor(bno_cur, error);
err_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)
{
struct xfs_perag *pag = ra->sc->sa.pag;
int error;
/* Free the old btree blocks if they're not in use. */
error = xrep_reap_agblocks(ra->sc, &ra->old_allocbt_blocks,
&XFS_RMAP_OINFO_AG, XFS_AG_RESV_IGNORE);
if (error)
return error;
/*
* Now that we've zapped all the old allocbt blocks we can turn off
* the alternate height mechanism.
*/
pag->pagf_repair_bno_level = 0;
pag->pagf_repair_cnt_level = 0;
return 0;
}
/* Repair the freespace btrees for some AG. */
int
xrep_allocbt(
struct xfs_scrub *sc)
{
struct xrep_abt *ra;
struct xfs_mount *mp = sc->mp;
char *descr;
int error;
/* We require the rmapbt to rebuild anything. */
if (!xfs_has_rmapbt(mp))
return -EOPNOTSUPP;
ra = kzalloc(sizeof(struct xrep_abt), XCHK_GFP_FLAGS);
if (!ra)
return -ENOMEM;
ra->sc = sc;
/* We rebuild both data structures. */
sc->sick_mask = XFS_SICK_AG_BNOBT | XFS_SICK_AG_CNTBT;
/*
* Make sure the busy extent list is clear because we can't put extents
* on there twice. In theory we cleared this before we started, but
* let's not risk the filesystem.
*/
if (!xfs_extent_busy_list_empty(sc->sa.pag)) {
error = -EDEADLOCK;
goto out_ra;
}
/* Set up enough storage to handle maximally fragmented free space. */
descr = xchk_xfile_ag_descr(sc, "free space records");
error = xfarray_create(descr, mp->m_sb.sb_agblocks / 2,
sizeof(struct xfs_alloc_rec_incore),
&ra->free_records);
kfree(descr);
if (error)
goto out_ra;
/* Collect the free space data and find the old btree blocks. */
xagb_bitmap_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);
if (error)
goto out_bitmap;
out_bitmap:
xagb_bitmap_destroy(&ra->old_allocbt_blocks);
xfarray_destroy(ra->free_records);
out_ra:
kfree(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_allocbt(sc);
if (error)
goto out;
sc->sm->sm_type = XFS_SCRUB_TYPE_CNTBT;
error = xchk_allocbt(sc);
out:
sc->sm->sm_type = old_type;
return error;
}