fs/xfs/scrub/rmap.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * Copyright (C) 2017 Oracle.  All Rights Reserved.
   4  * Author: Darrick J. Wong <darrick.wong@oracle.com>
   5  */
   6 #include "xfs.h"
   7 #include "xfs_fs.h"
   8 #include "xfs_shared.h"
   9 #include "xfs_format.h"
  10 #include "xfs_trans_resv.h"
  11 #include "xfs_mount.h"
  12 #include "xfs_btree.h"
  13 #include "xfs_rmap.h"
  14 #include "xfs_refcount.h"
  15 #include "scrub/scrub.h"
  16 #include "scrub/common.h"
  17 #include "scrub/btree.h"
  18
  19 /*
  20  * Set us up to scrub reverse mapping btrees.
  21  */
  22 int
  23 xchk_setup_ag_rmapbt(
  24         struct xfs_scrub        *sc,
  25         struct xfs_inode        *ip)
  26 {
  27         return xchk_setup_ag_btree(sc, ip, false);
  28 }
  29
  30 /* Reverse-mapping scrubber. */
  31
  32 /* Cross-reference a rmap against the refcount btree. */
  33 STATIC void
  34 xchk_rmapbt_xref_refc(
  35         struct xfs_scrub        *sc,
  36         struct xfs_rmap_irec    *irec)
  37 {
  38         xfs_agblock_t           fbno;
  39         xfs_extlen_t            flen;
  40         bool                    non_inode;
  41         bool                    is_bmbt;
  42         bool                    is_attr;
  43         bool                    is_unwritten;
  44         int                     error;
  45
  46         if (!sc->sa.refc_cur || xchk_skip_xref(sc->sm))
  47                 return;
  48
  49         non_inode = XFS_RMAP_NON_INODE_OWNER(irec->rm_owner);
  50         is_bmbt = irec->rm_flags & XFS_RMAP_BMBT_BLOCK;
  51         is_attr = irec->rm_flags & XFS_RMAP_ATTR_FORK;
  52         is_unwritten = irec->rm_flags & XFS_RMAP_UNWRITTEN;
  53
  54         /* If this is shared, must be a data fork extent. */
  55         error = xfs_refcount_find_shared(sc->sa.refc_cur, irec->rm_startblock,
  56                         irec->rm_blockcount, &fbno, &flen, false);
  57         if (!xchk_should_check_xref(sc, &error, &sc->sa.refc_cur))
  58                 return;
  59         if (flen != 0 && (non_inode || is_attr || is_bmbt || is_unwritten))
  60                 xchk_btree_xref_set_corrupt(sc, sc->sa.refc_cur, 0);
  61 }
  62
  63 /* Cross-reference with the other btrees. */
  64 STATIC void
  65 xchk_rmapbt_xref(
  66         struct xfs_scrub        *sc,
  67         struct xfs_rmap_irec    *irec)
  68 {
  69         xfs_agblock_t           agbno = irec->rm_startblock;
  70         xfs_extlen_t            len = irec->rm_blockcount;
  71
  72         if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
  73                 return;
  74
  75         xchk_xref_is_used_space(sc, agbno, len);
  76         if (irec->rm_owner == XFS_RMAP_OWN_INODES)
  77                 xchk_xref_is_inode_chunk(sc, agbno, len);
  78         else
  79                 xchk_xref_is_not_inode_chunk(sc, agbno, len);
  80         if (irec->rm_owner == XFS_RMAP_OWN_COW)
  81                 xchk_xref_is_cow_staging(sc, irec->rm_startblock,
  82                                 irec->rm_blockcount);
  83         else
  84                 xchk_rmapbt_xref_refc(sc, irec);
  85 }
  86
  87 /* Scrub an rmapbt record. */
  88 STATIC int
  89 xchk_rmapbt_rec(
  90         struct xchk_btree       *bs,
  91         union xfs_btree_rec     *rec)
  92 {
  93         struct xfs_mount        *mp = bs->cur->bc_mp;
  94         struct xfs_rmap_irec    irec;
  95         xfs_agnumber_t          agno = bs->cur->bc_ag.agno;
  96         bool                    non_inode;
  97         bool                    is_unwritten;
  98         bool                    is_bmbt;
  99         bool                    is_attr;
 100         int                     error;
 101
 102         error = xfs_rmap_btrec_to_irec(rec, &irec);
 103         if (!xchk_btree_process_error(bs->sc, bs->cur, 0, &error))
 104                 goto out;
 105
 106         /* Check extent. */
 107         if (irec.rm_startblock + irec.rm_blockcount <= irec.rm_startblock)
 108                 xchk_btree_set_corrupt(bs->sc, bs->cur, 0);
 109
 110         if (irec.rm_owner == XFS_RMAP_OWN_FS) {
 111                 /*
 112                  * xfs_verify_agbno returns false for static fs metadata.
 113                  * Since that only exists at the start of the AG, validate
 114                  * that by hand.
 115                  */
 116                 if (irec.rm_startblock != 0 ||
 117                     irec.rm_blockcount != XFS_AGFL_BLOCK(mp) + 1)
 118                         xchk_btree_set_corrupt(bs->sc, bs->cur, 0);
 119         } else {
 120                 /*
 121                  * Otherwise we must point somewhere past the static metadata
 122                  * but before the end of the FS.  Run the regular check.
 123                  */
 124                 if (!xfs_verify_agbno(mp, agno, irec.rm_startblock) ||
 125                     !xfs_verify_agbno(mp, agno, irec.rm_startblock +
 126                                 irec.rm_blockcount - 1))
 127                         xchk_btree_set_corrupt(bs->sc, bs->cur, 0);
 128         }
 129
 130         /* Check flags. */
 131         non_inode = XFS_RMAP_NON_INODE_OWNER(irec.rm_owner);
 132         is_bmbt = irec.rm_flags & XFS_RMAP_BMBT_BLOCK;
 133         is_attr = irec.rm_flags & XFS_RMAP_ATTR_FORK;
 134         is_unwritten = irec.rm_flags & XFS_RMAP_UNWRITTEN;
 135
 136         if (is_bmbt && irec.rm_offset != 0)
 137                 xchk_btree_set_corrupt(bs->sc, bs->cur, 0);
 138
 139         if (non_inode && irec.rm_offset != 0)
 140                 xchk_btree_set_corrupt(bs->sc, bs->cur, 0);
 141
 142         if (is_unwritten && (is_bmbt || non_inode || is_attr))
 143                 xchk_btree_set_corrupt(bs->sc, bs->cur, 0);
 144
 145         if (non_inode && (is_bmbt || is_unwritten || is_attr))
 146                 xchk_btree_set_corrupt(bs->sc, bs->cur, 0);
 147
 148         if (!non_inode) {
 149                 if (!xfs_verify_ino(mp, irec.rm_owner))
 150                         xchk_btree_set_corrupt(bs->sc, bs->cur, 0);
 151         } else {
 152                 /* Non-inode owner within the magic values? */
 153                 if (irec.rm_owner <= XFS_RMAP_OWN_MIN ||
 154                     irec.rm_owner > XFS_RMAP_OWN_FS)
 155                         xchk_btree_set_corrupt(bs->sc, bs->cur, 0);
 156         }
 157
 158         xchk_rmapbt_xref(bs->sc, &irec);
 159 out:
 160         return error;
 161 }
 162
 163 /* Scrub the rmap btree for some AG. */
 164 int
 165 xchk_rmapbt(
 166         struct xfs_scrub        *sc)
 167 {
 168         return xchk_btree(sc, sc->sa.rmap_cur, xchk_rmapbt_rec,
 169                         &XFS_RMAP_OINFO_AG, NULL);
 170 }
 171
 172 /* xref check that the extent is owned by a given owner */
 173 static inline void
 174 xchk_xref_check_owner(
 175         struct xfs_scrub                *sc,
 176         xfs_agblock_t                   bno,
 177         xfs_extlen_t                    len,
 178         const struct xfs_owner_info     *oinfo,
 179         bool                            should_have_rmap)
 180 {
 181         bool                            has_rmap;
 182         int                             error;
 183
 184         if (!sc->sa.rmap_cur || xchk_skip_xref(sc->sm))
 185                 return;
 186
 187         error = xfs_rmap_record_exists(sc->sa.rmap_cur, bno, len, oinfo,
 188                         &has_rmap);
 189         if (!xchk_should_check_xref(sc, &error, &sc->sa.rmap_cur))
 190                 return;
 191         if (has_rmap != should_have_rmap)
 192                 xchk_btree_xref_set_corrupt(sc, sc->sa.rmap_cur, 0);
 193 }
 194
 195 /* xref check that the extent is owned by a given owner */
 196 void
 197 xchk_xref_is_owned_by(
 198         struct xfs_scrub                *sc,
 199         xfs_agblock_t                   bno,
 200         xfs_extlen_t                    len,
 201         const struct xfs_owner_info     *oinfo)
 202 {
 203         xchk_xref_check_owner(sc, bno, len, oinfo, true);
 204 }
 205
 206 /* xref check that the extent is not owned by a given owner */
 207 void
 208 xchk_xref_is_not_owned_by(
 209         struct xfs_scrub                *sc,
 210         xfs_agblock_t                   bno,
 211         xfs_extlen_t                    len,
 212         const struct xfs_owner_info     *oinfo)
 213 {
 214         xchk_xref_check_owner(sc, bno, len, oinfo, false);
 215 }
 216
 217 /* xref check that the extent has no reverse mapping at all */
 218 void
 219 xchk_xref_has_no_owner(
 220         struct xfs_scrub        *sc,
 221         xfs_agblock_t           bno,
 222         xfs_extlen_t            len)
 223 {
 224         bool                    has_rmap;
 225         int                     error;
 226
 227         if (!sc->sa.rmap_cur || xchk_skip_xref(sc->sm))
 228                 return;
 229
 230         error = xfs_rmap_has_record(sc->sa.rmap_cur, bno, len, &has_rmap);
 231         if (!xchk_should_check_xref(sc, &error, &sc->sa.rmap_cur))
 232                 return;
 233         if (has_rmap)
 234                 xchk_btree_xref_set_corrupt(sc, sc->sa.rmap_cur, 0);
 235 }