fs/xfs/libxfs/xfs_dquot_buf.c

   1 /*
   2  * Copyright (c) 2000-2006 Silicon Graphics, Inc.
   3  * Copyright (c) 2013 Red Hat, Inc.
   4  * All Rights Reserved.
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public License as
   8  * published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it would be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program; if not, write the Free Software Foundation,
  17  * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  18  */
  19 #include "xfs.h"
  20 #include "xfs_fs.h"
  21 #include "xfs_shared.h"
  22 #include "xfs_format.h"
  23 #include "xfs_log_format.h"
  24 #include "xfs_trans_resv.h"
  25 #include "xfs_mount.h"
  26 #include "xfs_inode.h"
  27 #include "xfs_quota.h"
  28 #include "xfs_trans.h"
  29 #include "xfs_qm.h"
  30 #include "xfs_error.h"
  31 #include "xfs_cksum.h"
  32 #include "xfs_trace.h"
  33
  34 int
  35 xfs_calc_dquots_per_chunk(
  36         unsigned int            nbblks) /* basic block units */
  37 {
  38         unsigned int    ndquots;
  39
  40         ASSERT(nbblks > 0);
  41         ndquots = BBTOB(nbblks);
  42         do_div(ndquots, sizeof(xfs_dqblk_t));
  43
  44         return ndquots;
  45 }
  46
  47 /*
  48  * Do some primitive error checking on ondisk dquot data structures.
  49  */
  50 int
  51 xfs_dqcheck(
  52         struct xfs_mount *mp,
  53         xfs_disk_dquot_t *ddq,
  54         xfs_dqid_t       id,
  55         uint             type,    /* used only when IO_dorepair is true */
  56         uint             flags,
  57         const char       *str)
  58 {
  59         xfs_dqblk_t      *d = (xfs_dqblk_t *)ddq;
  60         int             errs = 0;
  61
  62         /*
  63          * We can encounter an uninitialized dquot buffer for 2 reasons:
  64          * 1. If we crash while deleting the quotainode(s), and those blks got
  65          *    used for user data. This is because we take the path of regular
  66          *    file deletion; however, the size field of quotainodes is never
  67          *    updated, so all the tricks that we play in itruncate_finish
  68          *    don't quite matter.
  69          *
  70          * 2. We don't play the quota buffers when there's a quotaoff logitem.
  71          *    But the allocation will be replayed so we'll end up with an
  72          *    uninitialized quota block.
  73          *
  74          * This is all fine; things are still consistent, and we haven't lost
  75          * any quota information. Just don't complain about bad dquot blks.
  76          */
  77         if (ddq->d_magic != cpu_to_be16(XFS_DQUOT_MAGIC)) {
  78                 if (flags & XFS_QMOPT_DOWARN)
  79                         xfs_alert(mp,
  80                         "%s : XFS dquot ID 0x%x, magic 0x%x != 0x%x",
  81                         str, id, be16_to_cpu(ddq->d_magic), XFS_DQUOT_MAGIC);
  82                 errs++;
  83         }
  84         if (ddq->d_version != XFS_DQUOT_VERSION) {
  85                 if (flags & XFS_QMOPT_DOWARN)
  86                         xfs_alert(mp,
  87                         "%s : XFS dquot ID 0x%x, version 0x%x != 0x%x",
  88                         str, id, ddq->d_version, XFS_DQUOT_VERSION);
  89                 errs++;
  90         }
  91
  92         if (ddq->d_flags != XFS_DQ_USER &&
  93             ddq->d_flags != XFS_DQ_PROJ &&
  94             ddq->d_flags != XFS_DQ_GROUP) {
  95                 if (flags & XFS_QMOPT_DOWARN)
  96                         xfs_alert(mp,
  97                         "%s : XFS dquot ID 0x%x, unknown flags 0x%x",
  98                         str, id, ddq->d_flags);
  99                 errs++;
 100         }
 101
 102         if (id != -1 && id != be32_to_cpu(ddq->d_id)) {
 103                 if (flags & XFS_QMOPT_DOWARN)
 104                         xfs_alert(mp,
 105                         "%s : ondisk-dquot 0x%p, ID mismatch: "
 106                         "0x%x expected, found id 0x%x",
 107                         str, ddq, id, be32_to_cpu(ddq->d_id));
 108                 errs++;
 109         }
 110
 111         if (!errs && ddq->d_id) {
 112                 if (ddq->d_blk_softlimit &&
 113                     be64_to_cpu(ddq->d_bcount) >
 114                                 be64_to_cpu(ddq->d_blk_softlimit)) {
 115                         if (!ddq->d_btimer) {
 116                                 if (flags & XFS_QMOPT_DOWARN)
 117                                         xfs_alert(mp,
 118                         "%s : Dquot ID 0x%x (0x%p) BLK TIMER NOT STARTED",
 119                                         str, (int)be32_to_cpu(ddq->d_id), ddq);
 120                                 errs++;
 121                         }
 122                 }
 123                 if (ddq->d_ino_softlimit &&
 124                     be64_to_cpu(ddq->d_icount) >
 125                                 be64_to_cpu(ddq->d_ino_softlimit)) {
 126                         if (!ddq->d_itimer) {
 127                                 if (flags & XFS_QMOPT_DOWARN)
 128                                         xfs_alert(mp,
 129                         "%s : Dquot ID 0x%x (0x%p) INODE TIMER NOT STARTED",
 130                                         str, (int)be32_to_cpu(ddq->d_id), ddq);
 131                                 errs++;
 132                         }
 133                 }
 134                 if (ddq->d_rtb_softlimit &&
 135                     be64_to_cpu(ddq->d_rtbcount) >
 136                                 be64_to_cpu(ddq->d_rtb_softlimit)) {
 137                         if (!ddq->d_rtbtimer) {
 138                                 if (flags & XFS_QMOPT_DOWARN)
 139                                         xfs_alert(mp,
 140                         "%s : Dquot ID 0x%x (0x%p) RTBLK TIMER NOT STARTED",
 141                                         str, (int)be32_to_cpu(ddq->d_id), ddq);
 142                                 errs++;
 143                         }
 144                 }
 145         }
 146
 147         if (!errs || !(flags & XFS_QMOPT_DQREPAIR))
 148                 return errs;
 149
 150         if (flags & XFS_QMOPT_DOWARN)
 151                 xfs_notice(mp, "Re-initializing dquot ID 0x%x", id);
 152
 153         /*
 154          * Typically, a repair is only requested by quotacheck.
 155          */
 156         ASSERT(id != -1);
 157         ASSERT(flags & XFS_QMOPT_DQREPAIR);
 158         memset(d, 0, sizeof(xfs_dqblk_t));
 159
 160         d->dd_diskdq.d_magic = cpu_to_be16(XFS_DQUOT_MAGIC);
 161         d->dd_diskdq.d_version = XFS_DQUOT_VERSION;
 162         d->dd_diskdq.d_flags = type;
 163         d->dd_diskdq.d_id = cpu_to_be32(id);
 164
 165         if (xfs_sb_version_hascrc(&mp->m_sb)) {
 166                 uuid_copy(&d->dd_uuid, &mp->m_sb.sb_meta_uuid);
 167                 xfs_update_cksum((char *)d, sizeof(struct xfs_dqblk),
 168                                  XFS_DQUOT_CRC_OFF);
 169         }
 170
 171         return errs;
 172 }
 173
 174 STATIC bool
 175 xfs_dquot_buf_verify_crc(
 176         struct xfs_mount        *mp,
 177         struct xfs_buf          *bp)
 178 {
 179         struct xfs_dqblk        *d = (struct xfs_dqblk *)bp->b_addr;
 180         int                     ndquots;
 181         int                     i;
 182
 183         if (!xfs_sb_version_hascrc(&mp->m_sb))
 184                 return true;
 185
 186         /*
 187          * if we are in log recovery, the quota subsystem has not been
 188          * initialised so we have no quotainfo structure. In that case, we need
 189          * to manually calculate the number of dquots in the buffer.
 190          */
 191         if (mp->m_quotainfo)
 192                 ndquots = mp->m_quotainfo->qi_dqperchunk;
 193         else
 194                 ndquots = xfs_calc_dquots_per_chunk(bp->b_length);
 195
 196         for (i = 0; i < ndquots; i++, d++) {
 197                 if (!xfs_verify_cksum((char *)d, sizeof(struct xfs_dqblk),
 198                                  XFS_DQUOT_CRC_OFF))
 199                         return false;
 200                 if (!uuid_equal(&d->dd_uuid, &mp->m_sb.sb_meta_uuid))
 201                         return false;
 202         }
 203         return true;
 204 }
 205
 206 STATIC bool
 207 xfs_dquot_buf_verify(
 208         struct xfs_mount        *mp,
 209         struct xfs_buf          *bp,
 210         int                     warn)
 211 {
 212         struct xfs_dqblk        *d = (struct xfs_dqblk *)bp->b_addr;
 213         xfs_dqid_t              id = 0;
 214         int                     ndquots;
 215         int                     i;
 216
 217         /*
 218          * if we are in log recovery, the quota subsystem has not been
 219          * initialised so we have no quotainfo structure. In that case, we need
 220          * to manually calculate the number of dquots in the buffer.
 221          */
 222         if (mp->m_quotainfo)
 223                 ndquots = mp->m_quotainfo->qi_dqperchunk;
 224         else
 225                 ndquots = xfs_calc_dquots_per_chunk(bp->b_length);
 226
 227         /*
 228          * On the first read of the buffer, verify that each dquot is valid.
 229          * We don't know what the id of the dquot is supposed to be, just that
 230          * they should be increasing monotonically within the buffer. If the
 231          * first id is corrupt, then it will fail on the second dquot in the
 232          * buffer so corruptions could point to the wrong dquot in this case.
 233          */
 234         for (i = 0; i < ndquots; i++) {
 235                 struct xfs_disk_dquot   *ddq;
 236                 int                     error;
 237
 238                 ddq = &d[i].dd_diskdq;
 239
 240                 if (i == 0)
 241                         id = be32_to_cpu(ddq->d_id);
 242
 243                 error = xfs_dqcheck(mp, ddq, id + i, 0, warn, __func__);
 244                 if (error)
 245                         return false;
 246         }
 247         return true;
 248 }
 249
 250 static void
 251 xfs_dquot_buf_read_verify(
 252         struct xfs_buf  *bp)
 253 {
 254         struct xfs_mount        *mp = bp->b_target->bt_mount;
 255
 256         if (!xfs_dquot_buf_verify_crc(mp, bp))
 257                 xfs_buf_ioerror(bp, -EFSBADCRC);
 258         else if (!xfs_dquot_buf_verify(mp, bp, XFS_QMOPT_DOWARN))
 259                 xfs_buf_ioerror(bp, -EFSCORRUPTED);
 260
 261         if (bp->b_error)
 262                 xfs_verifier_error(bp);
 263 }
 264
 265 /*
 266  * readahead errors are silent and simply leave the buffer as !done so a real
 267  * read will then be run with the xfs_dquot_buf_ops verifier. See
 268  * xfs_inode_buf_verify() for why we use EIO and ~XBF_DONE here rather than
 269  * reporting the failure.
 270  */
 271 static void
 272 xfs_dquot_buf_readahead_verify(
 273         struct xfs_buf  *bp)
 274 {
 275         struct xfs_mount        *mp = bp->b_target->bt_mount;
 276
 277         if (!xfs_dquot_buf_verify_crc(mp, bp) ||
 278             !xfs_dquot_buf_verify(mp, bp, 0)) {
 279                 xfs_buf_ioerror(bp, -EIO);
 280                 bp->b_flags &= ~XBF_DONE;
 281         }
 282 }
 283
 284 /*
 285  * we don't calculate the CRC here as that is done when the dquot is flushed to
 286  * the buffer after the update is done. This ensures that the dquot in the
 287  * buffer always has an up-to-date CRC value.
 288  */
 289 static void
 290 xfs_dquot_buf_write_verify(
 291         struct xfs_buf  *bp)
 292 {
 293         struct xfs_mount        *mp = bp->b_target->bt_mount;
 294
 295         if (!xfs_dquot_buf_verify(mp, bp, XFS_QMOPT_DOWARN)) {
 296                 xfs_buf_ioerror(bp, -EFSCORRUPTED);
 297                 xfs_verifier_error(bp);
 298                 return;
 299         }
 300 }
 301
 302 const struct xfs_buf_ops xfs_dquot_buf_ops = {
 303         .name = "xfs_dquot",
 304         .verify_read = xfs_dquot_buf_read_verify,
 305         .verify_write = xfs_dquot_buf_write_verify,
 306 };
 307
 308 const struct xfs_buf_ops xfs_dquot_buf_ra_ops = {
 309         .name = "xfs_dquot_ra",
 310         .verify_read = xfs_dquot_buf_readahead_verify,
 311         .verify_write = xfs_dquot_buf_write_verify,
 312 };