[PATCH 01/14] xfs: repair the AGF and AGFL

Darrick J. Wong
2018-05-30T19:30:48Z

From: Darrick J. Wong <darrick.wong@oracle.com>

Regenerate the AGF and AGFL from the rmap data.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
fs/xfs/scrub/agheader_repair.c | 484 ++++++++++++++++++++++++++++++++++++++++
fs/xfs/scrub/repair.c | 30 ++
fs/xfs/scrub/repair.h | 6
fs/xfs/scrub/scrub.c | 4
fs/xfs/xfs_trans.c | 54 ++++
fs/xfs/xfs_trans.h | 2
6 files changed, 578 insertions(+), 2 deletions(-)

diff --git a/fs/xfs/scrub/agheader_repair.c b/fs/xfs/scrub/agheader_repair.c
index 8b91e9ebe1e7..0f794d27382a 100644
--- a/fs/xfs/scrub/agheader_repair.c
+++ b/fs/xfs/scrub/agheader_repair.c
@@ -31,12 +31,18 @@
#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"

/* Superblock */

@@ -68,3 +74,481 @@ xfs_repair_superblock(
xfs_trans_log_buf(sc->tp, bp, 0, BBTOB(bp->b_length) - 1);
return error;
}
+
+/* AGF */
+
+struct xfs_repair_agf_allocbt {
+ struct xfs_scrub_context *sc;
+ xfs_agblock_t freeblks;
+ xfs_agblock_t longest;
+};
+
+/* Record free space shape information. */
+STATIC int
+xfs_repair_agf_walk_allocbt(
+ struct xfs_btree_cur *cur,
+ struct xfs_alloc_rec_incore *rec,
+ void *priv)
+{
+ struct xfs_repair_agf_allocbt *raa = priv;
+ int error = 0;
+
+ if (xfs_scrub_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
+xfs_repair_agf_check_agfl_block(
+ struct xfs_mount *mp,
+ xfs_agblock_t agbno,
+ void *priv)
+{
+ struct xfs_scrub_context *sc = priv;
+
+ if (!xfs_verify_agbno(mp, sc->sa.agno, agbno))
+ return -EFSCORRUPTED;
+ return 0;
+}
+
+/* Repair the AGF. */
+int
+xfs_repair_agf(
+ struct xfs_scrub_context *sc)
+{
+ struct xfs_repair_find_ag_btree fab[] = {
+ {
+ .rmap_owner = XFS_RMAP_OWN_AG,
+ .buf_ops = &xfs_allocbt_buf_ops,
+ .magic = XFS_ABTB_CRC_MAGIC,
+ },
+ {
+ .rmap_owner = XFS_RMAP_OWN_AG,
+ .buf_ops = &xfs_allocbt_buf_ops,
+ .magic = XFS_ABTC_CRC_MAGIC,
+ },
+ {
+ .rmap_owner = XFS_RMAP_OWN_AG,
+ .buf_ops = &xfs_rmapbt_buf_ops,
+ .magic = XFS_RMAP_CRC_MAGIC,
+ },
+ {
+ .rmap_owner = XFS_RMAP_OWN_REFC,
+ .buf_ops = &xfs_refcountbt_buf_ops,
+ .magic = XFS_REFC_CRC_MAGIC,
+ },
+ {
+ .buf_ops = NULL,
+ },
+ };
+ struct xfs_repair_agf_allocbt raa;
+ 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;
+ struct xfs_btree_cur *cur = NULL;
+ struct xfs_perag *pag;
+ xfs_agblock_t blocks;
+ xfs_agblock_t freesp_blocks;
+ int64_t delta_fdblocks = 0;
+ int error;
+
+ /* We require the rmapbt to rebuild anything. */
+ if (!xfs_sb_version_hasrmapbt(&mp->m_sb))
+ return -EOPNOTSUPP;
+
+ xfs_scrub_perag_get(sc->mp, &sc->sa);
+ pag = sc->sa.pag;
+ memset(&raa, 0, sizeof(raa));
+ 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;
+
+ /*
+ * 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.
+ */
+ error = xfs_alloc_read_agfl(mp, sc->tp, sc->sa.agno, &agfl_bp);
+ if (error)
+ return error;
+ error = xfs_agfl_walk(sc->mp, XFS_BUF_TO_AGF(agf_bp), agfl_bp,
+ xfs_repair_agf_check_agfl_block, sc);
+ if (error)
+ return error;
+
+ /* Find the btree roots. */
+ error = xfs_repair_find_ag_btree_roots(sc, agf_bp, fab, agfl_bp);
+ if (error)
+ return error;
+ if (fab[0].root == NULLAGBLOCK || fab[0].height > XFS_BTREE_MAXLEVELS ||
+ fab[1].root == NULLAGBLOCK || fab[1].height > XFS_BTREE_MAXLEVELS ||
+ fab[2].root == NULLAGBLOCK || fab[2].height > XFS_BTREE_MAXLEVELS)
+ return -EFSCORRUPTED;
+ if (xfs_sb_version_hasreflink(&mp->m_sb) &&
+ (fab[3].root == NULLAGBLOCK || fab[3].height > XFS_BTREE_MAXLEVELS))
+ return -EFSCORRUPTED;
+
+ /* Start rewriting the header. */
+ agf = XFS_BUF_TO_AGF(agf_bp);
+ memcpy(&old_agf, agf, sizeof(old_agf));
+
+ /*
+ * We relied on the rmapbt to reconstruct the AGF. If we get a
+ * different root then something's seriously wrong.
+ */
+ if (be32_to_cpu(old_agf.agf_roots[XFS_BTNUM_RMAPi]) != fab[2].root)
+ return -EFSCORRUPTED;
+ memset(agf, 0, mp->m_sb.sb_sectsize);
+ 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_roots[XFS_BTNUM_BNOi] = cpu_to_be32(fab[0].root);
+ agf->agf_roots[XFS_BTNUM_CNTi] = cpu_to_be32(fab[1].root);
+ agf->agf_roots[XFS_BTNUM_RMAPi] = cpu_to_be32(fab[2].root);
+ agf->agf_levels[XFS_BTNUM_BNOi] = cpu_to_be32(fab[0].height);
+ agf->agf_levels[XFS_BTNUM_CNTi] = cpu_to_be32(fab[1].height);
+ agf->agf_levels[XFS_BTNUM_RMAPi] = cpu_to_be32(fab[2].height);
+ 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);
+ if (xfs_sb_version_hasreflink(&mp->m_sb)) {
+ agf->agf_refcount_root = cpu_to_be32(fab[3].root);
+ agf->agf_refcount_level = cpu_to_be32(fab[3].height);
+ }
+
+ /* Update the AGF counters from the bnobt. */
+ cur = xfs_allocbt_init_cursor(mp, sc->tp, agf_bp, sc->sa.agno,
+ XFS_BTNUM_BNO);
+ raa.sc = sc;
+ error = xfs_alloc_query_all(cur, xfs_repair_agf_walk_allocbt, &raa);
+ if (error)
+ goto err;
+ error = xfs_btree_count_blocks(cur, &blocks);
+ if (error)
+ goto err;
+ xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
+ freesp_blocks = 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, XFS_BTREE_NOERROR);
+ freesp_blocks += 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, XFS_BTREE_NOERROR);
+ agf->agf_rmap_blocks = cpu_to_be32(blocks);
+ freesp_blocks += blocks - 1;
+
+ /* 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, NULL);
+ error = xfs_btree_count_blocks(cur, &blocks);
+ if (error)
+ goto err;
+ xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
+ agf->agf_refcount_blocks = cpu_to_be32(blocks);
+ }
+ agf->agf_btreeblks = cpu_to_be32(freesp_blocks);
+ cur = NULL;
+
+ /* Trigger reinitialization of the in-core data. */
+ if (raa.freeblks != be32_to_cpu(old_agf.agf_freeblks)) {
+ delta_fdblocks += (int64_t)raa.freeblks -
+ be32_to_cpu(old_agf.agf_freeblks);
+ if (pag->pagf_init)
+ pag->pagf_freeblks = be32_to_cpu(agf->agf_freeblks);
+ }
+
+ if (freesp_blocks != be32_to_cpu(old_agf.agf_btreeblks)) {
+ delta_fdblocks += (int64_t)freesp_blocks -
+ be32_to_cpu(old_agf.agf_btreeblks);
+ if (pag->pagf_init)
+ pag->pagf_btreeblks = be32_to_cpu(agf->agf_btreeblks);
+ }
+
+ if (pag->pagf_init &&
+ (raa.longest != be32_to_cpu(old_agf.agf_longest) ||
+ fab[0].height != be32_to_cpu(old_agf.agf_levels[XFS_BTNUM_BNOi]) ||
+ fab[1].height != be32_to_cpu(old_agf.agf_levels[XFS_BTNUM_CNTi]) ||
+ fab[2].height != be32_to_cpu(old_agf.agf_levels[XFS_BTNUM_RMAPi]) ||
+ fab[3].height != be32_to_cpu(old_agf.agf_refcount_level))) {
+ 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);
+ }
+
+ error = xfs_repair_mod_fdblocks(sc, delta_fdblocks);
+ if (error)
+ goto err;
+
+ /* 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);
+ return error;
+
+err:
+ if (cur)
+ xfs_btree_del_cursor(cur, error ? XFS_BTREE_ERROR :
+ XFS_BTREE_NOERROR);
+ memcpy(agf, &old_agf, sizeof(old_agf));
+ return error;
+}
+
+/* AGFL */
+
+struct xfs_repair_agfl {
+ struct xfs_repair_extent_list freesp_list;
+ struct xfs_repair_extent_list agmeta_list;
+ struct xfs_scrub_context *sc;
+};
+
+/* Record all freespace information. */
+STATIC int
+xfs_repair_agfl_rmap_fn(
+ struct xfs_btree_cur *cur,
+ struct xfs_rmap_irec *rec,
+ void *priv)
+{
+ struct xfs_repair_agfl *ra = priv;
+ struct xfs_buf *bp;
+ xfs_fsblock_t fsb;
+ int i;
+ int error = 0;
+
+ if (xfs_scrub_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_repair_collect_btree_extent(ra->sc,
+ &ra->freesp_list, fsb, rec->rm_blockcount);
+ if (error)
+ return error;
+ }
+
+ /* ...and all the rmapbt blocks... */
+ for (i = 0; i < cur->bc_nlevels && cur->bc_ptrs[i] == 1; i++) {
+ xfs_btree_get_block(cur, i, &bp);
+ if (!bp)
+ continue;
+ fsb = XFS_DADDR_TO_FSB(cur->bc_mp, bp->b_bn);
+ error = xfs_repair_collect_btree_extent(ra->sc,
+ &ra->agmeta_list, fsb, 1);
+ if (error)
+ return error;
+ }
+
+ return 0;
+}
+
+/* Add a btree block to the agmeta list. */
+STATIC int
+xfs_repair_agfl_visit_btblock(
+ struct xfs_btree_cur *cur,
+ int level,
+ void *priv)
+{
+ struct xfs_repair_agfl *ra = priv;
+ struct xfs_buf *bp;
+ xfs_fsblock_t fsb;
+ int error = 0;
+
+ if (xfs_scrub_should_terminate(ra->sc, &error))
+ return error;
+
+ xfs_btree_get_block(cur, level, &bp);
+ if (!bp)
+ return 0;
+
+ fsb = XFS_DADDR_TO_FSB(cur->bc_mp, bp->b_bn);
+ return xfs_repair_collect_btree_extent(ra->sc, &ra->agmeta_list,
+ fsb, 1);
+}
+
+/* Repair the AGFL. */
+int
+xfs_repair_agfl(
+ struct xfs_scrub_context *sc)
+{
+ struct xfs_repair_agfl ra;
+ struct xfs_owner_info oinfo;
+ struct xfs_mount *mp = sc->mp;
+ struct xfs_buf *agf_bp;
+ struct xfs_buf *agfl_bp;
+ struct xfs_agf *agf;
+ struct xfs_agfl *agfl;
+ struct xfs_btree_cur *cur = NULL;
+ __be32 *agfl_bno;
+ struct xfs_repair_extent *rae;
+ struct xfs_repair_extent *n;
+ xfs_agblock_t flcount;
+ xfs_agblock_t agbno;
+ xfs_agblock_t bno;
+ xfs_agblock_t old_flcount;
+ int error;
+
+ /* We require the rmapbt to rebuild anything. */
+ if (!xfs_sb_version_hasrmapbt(&mp->m_sb))
+ return -EOPNOTSUPP;
+
+ xfs_scrub_perag_get(sc->mp, &sc->sa);
+ xfs_repair_init_extent_list(&ra.freesp_list);
+ xfs_repair_init_extent_list(&ra.agmeta_list);
+ ra.sc = sc;
+
+ error = xfs_alloc_read_agf(mp, sc->tp, sc->sa.agno, 0, &agf_bp);
+ if (error)
+ return error;
+ if (!agf_bp)
+ return -ENOMEM;
+
+ 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;
+
+ /* 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, xfs_repair_agfl_rmap_fn, &ra);
+ if (error)
+ goto err;
+ xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
+
+ /* Find all space used by bnobt. */
+ cur = xfs_allocbt_init_cursor(mp, sc->tp, agf_bp, sc->sa.agno,
+ XFS_BTNUM_BNO);
+ error = xfs_btree_visit_blocks(cur, xfs_repair_agfl_visit_btblock,
+ &ra);
+ if (error)
+ goto err;
+ xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
+
+ /* Find all space used by cntbt. */
+ cur = xfs_allocbt_init_cursor(mp, sc->tp, agf_bp, sc->sa.agno,
+ XFS_BTNUM_CNT);
+ error = xfs_btree_visit_blocks(cur, xfs_repair_agfl_visit_btblock,
+ &ra);
+ if (error)
+ goto err;
+ xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
+ cur = NULL;
+
+ /*
+ * Drop the freesp meta blocks that are in use by btrees.
+ * The remaining blocks /should/ be AGFL blocks.
+ */
+ error = xfs_repair_subtract_extents(sc, &ra.freesp_list,
+ &ra.agmeta_list);
+ if (error)
+ goto err;
+ xfs_repair_cancel_btree_extents(sc, &ra.agmeta_list);
+
+ /* Calculate the new AGFL size. */
+ flcount = 0;
+ for_each_xfs_repair_extent_safe(rae, n, &ra.freesp_list) {
+ for (bno = 0; bno < rae->len; bno++) {
+ if (flcount >= xfs_agfl_size(mp) - 1)
+ break;
+ flcount++;
+ }
+ }
+
+ /* Update fdblocks if flcount changed. */
+ agf = XFS_BUF_TO_AGF(agf_bp);
+ old_flcount = be32_to_cpu(agf->agf_flcount);
+ if (flcount != old_flcount) {
+ int64_t delta_fdblocks = (int64_t)flcount - old_flcount;
+
+ error = xfs_repair_mod_fdblocks(sc, delta_fdblocks);
+ if (error)
+ goto err;
+ if (sc->sa.pag->pagf_init)
+ sc->sa.pag->pagf_flcount = flcount;
+ }
+
+ /* Update the AGF pointers. */
+ agf->agf_flfirst = cpu_to_be32(1);
+ agf->agf_flcount = cpu_to_be32(flcount);
+ agf->agf_fllast = cpu_to_be32(flcount);
+
+ /* Start rewriting the header. */
+ agfl = XFS_BUF_TO_AGFL(agfl_bp);
+ memset(agfl, 0xFF, mp->m_sb.sb_sectsize);
+ 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. */
+ flcount = 0;
+ agfl_bno = XFS_BUF_TO_AGFL_BNO(mp, agfl_bp);
+ for_each_xfs_repair_extent_safe(rae, n, &ra.freesp_list) {
+ agbno = XFS_FSB_TO_AGBNO(mp, rae->fsbno);
+
+ trace_xfs_repair_agfl_insert(mp, sc->sa.agno, agbno, rae->len);
+
+ for (bno = 0; bno < rae->len; bno++) {
+ if (flcount >= xfs_agfl_size(mp) - 1)
+ break;
+ agfl_bno[flcount + 1] = cpu_to_be32(agbno + bno);
+ flcount++;
+ }
+ rae->fsbno += bno;
+ rae->len -= bno;
+ if (rae->len)
+ break;
+ list_del(&rae->list);
+ kmem_free(rae);
+ }
+
+ /* Write AGF and AGFL to disk. */
+ xfs_alloc_log_agf(sc->tp, agf_bp,
+ XFS_AGF_FLFIRST | XFS_AGF_FLLAST | XFS_AGF_FLCOUNT);
+ 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);
+
+ /* Dump any AGFL overflow. */
+ xfs_rmap_ag_owner(&oinfo, XFS_RMAP_OWN_AG);
+ return xfs_repair_reap_btree_extents(sc, &ra.freesp_list, &oinfo,
+ XFS_AG_RESV_AGFL);
+err:
+ xfs_repair_cancel_btree_extents(sc, &ra.agmeta_list);
+ xfs_repair_cancel_btree_extents(sc, &ra.freesp_list);
+ if (cur)
+ xfs_btree_del_cursor(cur, error ? XFS_BTREE_ERROR :
+ XFS_BTREE_NOERROR);
+ return error;
+}
diff --git a/fs/xfs/scrub/repair.c b/fs/xfs/scrub/repair.c
index e3e8fba1c99c..5f31dc8af505 100644
--- a/fs/xfs/scrub/repair.c
+++ b/fs/xfs/scrub/repair.c
@@ -1087,3 +1087,33 @@ xfs_repair_ino_dqattach(

return error;
}
+
+/*
+ * We changed this AGF's free block count, so now we need to reset the global
+ * counters. We use the transaction to update the global counters, so if the
+ * AG free counts were low we have to ask the transaction for more block
+ * reservation before decreasing fdblocks.
+ *
+ * XXX: We ought to have some mechanism for checking and fixing the superblock
+ * counters (particularly if we're close to ENOSPC) but that's left as an open
+ * research question for now.
+ */
+int
+xfs_repair_mod_fdblocks(
+ struct xfs_scrub_context *sc,
+ int64_t delta_fdblocks)
+{
+ int error;
+
+ if (delta_fdblocks == 0)
+ return 0;
+
+ if (delta_fdblocks < 0) {
+ error = xfs_trans_reserve_more(sc->tp, -delta_fdblocks, 0);
+ if (error)
+ return error;
+ }
+
+ xfs_trans_mod_sb(sc->tp, XFS_TRANS_SB_FDBLOCKS, delta_fdblocks);
+ return 0;
+}
diff --git a/fs/xfs/scrub/repair.h b/fs/xfs/scrub/repair.h
index f2b0895294db..97794c281a23 100644
--- a/fs/xfs/scrub/repair.h
+++ b/fs/xfs/scrub/repair.h
@@ -98,11 +98,15 @@ int xfs_repair_find_ag_btree_roots(struct xfs_scrub_context *sc,
struct xfs_buf *agfl_bp);
void xfs_repair_force_quotacheck(struct xfs_scrub_context *sc, uint dqtype);
int xfs_repair_ino_dqattach(struct xfs_scrub_context *sc);
+int xfs_repair_mod_fdblocks(struct xfs_scrub_context *sc,
+ int64_t delta_fdblocks);

/* Metadata repairers */

int xfs_repair_probe(struct xfs_scrub_context *sc);
int xfs_repair_superblock(struct xfs_scrub_context *sc);
+int xfs_repair_agf(struct xfs_scrub_context *sc);
+int xfs_repair_agfl(struct xfs_scrub_context *sc);

#else

@@ -126,6 +130,8 @@ xfs_repair_calc_ag_resblks(

#define xfs_repair_probe xfs_repair_notsupported
#define xfs_repair_superblock xfs_repair_notsupported
+#define xfs_repair_agf xfs_repair_notsupported
+#define xfs_repair_agfl xfs_repair_notsupported

#endif /* CONFIG_XFS_ONLINE_REPAIR */

diff --git a/fs/xfs/scrub/scrub.c b/fs/xfs/scrub/scrub.c
index 36db098ba583..0b523ab9b8b0 100644
--- a/fs/xfs/scrub/scrub.c
+++ b/fs/xfs/scrub/scrub.c
@@ -222,13 +222,13 @@ static const struct xfs_scrub_meta_ops meta_scrub_ops[] = {
.type = ST_PERAG,
.setup = xfs_scrub_setup_fs,
.scrub = xfs_scrub_agf,
- .repair = xfs_repair_notsupported,
+ .repair = xfs_repair_agf,
},
[XFS_SCRUB_TYPE_AGFL]= { /* agfl */
.type = ST_PERAG,
.setup = xfs_scrub_setup_fs,
.scrub = xfs_scrub_agfl,
- .repair = xfs_repair_notsupported,
+ .repair = xfs_repair_agfl,
},
[XFS_SCRUB_TYPE_AGI] = { /* agi */
.type = ST_PERAG,
diff --git a/fs/xfs/xfs_trans.c b/fs/xfs/xfs_trans.c
index fc7ba75b8b69..5c24e66170fe 100644
--- a/fs/xfs/xfs_trans.c
+++ b/fs/xfs/xfs_trans.c
@@ -138,6 +138,60 @@ xfs_trans_dup(
return ntp;
}

+/*
+ * Try to reserve more blocks for a transaction. The single use case we
+ * support is for online repair -- use a transaction to gather data without
+ * fear of btree cycle deadlocks; calculate how many blocks we really need
+ * from that data; and only then start modifying data. This can fail due to
+ * ENOSPC, so we have to be able to cancel the transaction.
+ */
+int
+xfs_trans_reserve_more(
+ struct xfs_trans *tp,
+ uint blocks,
+ uint rtextents)
+{
+ struct xfs_mount *mp = tp->t_mountp;
+ bool rsvd = (tp->t_flags & XFS_TRANS_RESERVE) != 0;
+ int error = 0;
+
+ ASSERT(!(tp->t_flags & XFS_TRANS_DIRTY));
+
+ /*
+ * Attempt to reserve the needed disk blocks by decrementing
+ * the number needed from the number available. This will
+ * fail if the count would go below zero.
+ */
+ if (blocks > 0) {
+ error = xfs_mod_fdblocks(mp, -((int64_t)blocks), rsvd);
+ if (error != 0)
+ return -ENOSPC;
+ tp->t_blk_res += blocks;
+ }
+
+ /*
+ * Attempt to reserve the needed realtime extents by decrementing
+ * the number needed from the number available. This will
+ * fail if the count would go below zero.
+ */
+ if (rtextents > 0) {
+ error = xfs_mod_frextents(mp, -((int64_t)rtextents));
+ if (error) {
+ error = -ENOSPC;
+ goto out_blocks;
+ }
+ tp->t_rtx_res += rtextents;
+ }
+
+ return 0;
+out_blocks:
+ if (blocks > 0) {
+ xfs_mod_fdblocks(mp, (int64_t)blocks, rsvd);
+ tp->t_blk_res -= blocks;
+ }
+ return error;
+}
+
/*
* This is called to reserve free disk blocks and log space for the
* given transaction. This must be done before allocating any resources
diff --git a/fs/xfs/xfs_trans.h b/fs/xfs/xfs_trans.h
index 29706b8b3bd4..7284555c4801 100644
--- a/fs/xfs/xfs_trans.h
+++ b/fs/xfs/xfs_trans.h
@@ -165,6 +165,8 @@ typedef struct xfs_trans {
int xfs_trans_alloc(struct xfs_mount *mp, struct xfs_trans_res *resp,
uint blocks, uint rtextents, uint flags,
struct xfs_trans **tpp);
+int xfs_trans_reserve_more(struct xfs_trans *tp, uint blocks,
+ uint rtextents);
int xfs_trans_alloc_empty(struct xfs_mount *mp,
struct xfs_trans **tpp);
void xfs_trans_mod_sb(xfs_trans_t *, uint, int64_t);