fs/xfs/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_sb.h"
  26 #include "xfs_ag.h"
  27 #include "xfs_mount.h"
  28 #include "xfs_inode.h"
  29 #include "xfs_quota.h"
  30 #include "xfs_trans.h"
  31 #include "xfs_qm.h"
  32 #include "xfs_error.h"
  33 #include "xfs_cksum.h"
  34 #include "xfs_trace.h"
  35
  36 int
  37 xfs_calc_dquots_per_chunk(
  38         unsigned int            nbblks) /* basic block units */
  39 {
  40         unsigned int    ndquots;
  41
  42         ASSERT(nbblks > 0);
  43         ndquots = BBTOB(nbblks);
  44         do_div(ndquots, sizeof(xfs_dqblk_t));
  45
  46         return ndquots;
  47 }
  48
  49 /*
  50  * Do some primitive error checking on ondisk dquot data structures.
  51  */
  52 int
  53 xfs_dqcheck(
  54         struct xfs_mount *mp,
  55         xfs_disk_dquot_t *ddq,
  56         xfs_dqid_t       id,
  57         uint             type,    /* used only when IO_dorepair is true */
  58         uint             flags,
  59         const char       *str)
  60 {
  61         xfs_dqblk_t      *d = (xfs_dqblk_t *)ddq;
  62         int             errs = 0;
  63
  64         /*
  65          * We can encounter an uninitialized dquot buffer for 2 reasons:
  66          * 1. If we crash while deleting the quotainode(s), and those blks got
  67          *    used for user data. This is because we take the path of regular
  68          *    file deletion; however, the size field of quotainodes is never
  69          *    updated, so all the tricks that we play in itruncate_finish
  70          *    don't quite matter.
  71          *
  72          * 2. We don't play the quota buffers when there's a quotaoff logitem.
  73          *    But the allocation will be replayed so we'll end up with an
  74          *    uninitialized quota block.
  75          *
  76          * This is all fine; things are still consistent, and we haven't lost
  77          * any quota information. Just don't complain about bad dquot blks.
  78          */
  79         if (ddq->d_magic != cpu_to_be16(XFS_DQUOT_MAGIC)) {
  80                 if (flags & XFS_QMOPT_DOWARN)
  81                         xfs_alert(mp,
  82                         "%s : XFS dquot ID 0x%x, magic 0x%x != 0x%x",
  83                         str, id, be16_to_cpu(ddq->d_magic), XFS_DQUOT_MAGIC);
  84                 errs++;
  85         }
  86         if (ddq->d_version != XFS_DQUOT_VERSION) {
  87                 if (flags & XFS_QMOPT_DOWARN)
  88                         xfs_alert(mp,
  89                         "%s : XFS dquot ID 0x%x, version 0x%x != 0x%x",
  90                         str, id, ddq->d_version, XFS_DQUOT_VERSION);
  91                 errs++;
  92         }
  93
  94         if (ddq->d_flags != XFS_DQ_USER &&
  95             ddq->d_flags != XFS_DQ_PROJ &&
  96             ddq->d_flags != XFS_DQ_GROUP) {
  97                 if (flags & XFS_QMOPT_DOWARN)
  98                         xfs_alert(mp,
  99                         "%s : XFS dquot ID 0x%x, unknown flags 0x%x",
 100                         str, id, ddq->d_flags);
 101                 errs++;
 102         }
 103
 104         if (id != -1 && id != be32_to_cpu(ddq->d_id)) {
 105                 if (flags & XFS_QMOPT_DOWARN)
 106                         xfs_alert(mp,
 107                         "%s : ondisk-dquot 0x%p, ID mismatch: "
 108                         "0x%x expected, found id 0x%x",
 109                         str, ddq, id, be32_to_cpu(ddq->d_id));
 110                 errs++;
 111         }
 112
 113         if (!errs && ddq->d_id) {
 114                 if (ddq->d_blk_softlimit &&
 115                     be64_to_cpu(ddq->d_bcount) >
 116                                 be64_to_cpu(ddq->d_blk_softlimit)) {
 117                         if (!ddq->d_btimer) {
 118                                 if (flags & XFS_QMOPT_DOWARN)
 119                                         xfs_alert(mp,
 120                         "%s : Dquot ID 0x%x (0x%p) BLK TIMER NOT STARTED",
 121                                         str, (int)be32_to_cpu(ddq->d_id), ddq);
 122                                 errs++;
 123                         }
 124                 }
 125                 if (ddq->d_ino_softlimit &&
 126                     be64_to_cpu(ddq->d_icount) >
 127                                 be64_to_cpu(ddq->d_ino_softlimit)) {
 128                         if (!ddq->d_itimer) {
 129                                 if (flags & XFS_QMOPT_DOWARN)
 130                                         xfs_alert(mp,
 131                         "%s : Dquot ID 0x%x (0x%p) INODE TIMER NOT STARTED",
 132                                         str, (int)be32_to_cpu(ddq->d_id), ddq);
 133                                 errs++;
 134                         }
 135                 }
 136                 if (ddq->d_rtb_softlimit &&
 137                     be64_to_cpu(ddq->d_rtbcount) >
 138                                 be64_to_cpu(ddq->d_rtb_softlimit)) {
 139                         if (!ddq->d_rtbtimer) {
 140                                 if (flags & XFS_QMOPT_DOWARN)
 141                                         xfs_alert(mp,
 142                         "%s : Dquot ID 0x%x (0x%p) RTBLK TIMER NOT STARTED",
 143                                         str, (int)be32_to_cpu(ddq->d_id), ddq);
 144                                 errs++;
 145                         }
 146                 }
 147         }
 148
 149         if (!errs || !(flags & XFS_QMOPT_DQREPAIR))
 150                 return errs;
 151
 152         if (flags & XFS_QMOPT_DOWARN)
 153                 xfs_notice(mp, "Re-initializing dquot ID 0x%x", id);
 154
 155         /*
 156          * Typically, a repair is only requested by quotacheck.
 157          */
 158         ASSERT(id != -1);
 159         ASSERT(flags & XFS_QMOPT_DQREPAIR);
 160         memset(d, 0, sizeof(xfs_dqblk_t));
 161
 162         d->dd_diskdq.d_magic = cpu_to_be16(XFS_DQUOT_MAGIC);
 163         d->dd_diskdq.d_version = XFS_DQUOT_VERSION;
 164         d->dd_diskdq.d_flags = type;
 165         d->dd_diskdq.d_id = cpu_to_be32(id);
 166
 167         if (xfs_sb_version_hascrc(&mp->m_sb)) {
 168                 uuid_copy(&d->dd_uuid, &mp->m_sb.sb_uuid);
 169                 xfs_update_cksum((char *)d, sizeof(struct xfs_dqblk),
 170                                  XFS_DQUOT_CRC_OFF);
 171         }
 172
 173         return errs;
 174 }
 175
 176 STATIC bool
 177 xfs_dquot_buf_verify_crc(
 178         struct xfs_mount        *mp,
 179         struct xfs_buf          *bp)
 180 {
 181         struct xfs_dqblk        *d = (struct xfs_dqblk *)bp->b_addr;
 182         int                     ndquots;
 183         int                     i;
 184
 185         if (!xfs_sb_version_hascrc(&mp->m_sb))
 186                 return true;
 187
 188         /*
 189          * if we are in log recovery, the quota subsystem has not been
 190          * initialised so we have no quotainfo structure. In that case, we need
 191          * to manually calculate the number of dquots in the buffer.
 192          */
 193         if (mp->m_quotainfo)
 194                 ndquots = mp->m_quotainfo->qi_dqperchunk;
 195         else
 196                 ndquots = xfs_calc_dquots_per_chunk(
 197                                         XFS_BB_TO_FSB(mp, bp->b_length));
 198
 199         for (i = 0; i < ndquots; i++, d++) {
 200                 if (!xfs_verify_cksum((char *)d, sizeof(struct xfs_dqblk),
 201                                  XFS_DQUOT_CRC_OFF))
 202                         return false;
 203                 if (!uuid_equal(&d->dd_uuid, &mp->m_sb.sb_uuid))
 204                         return false;
 205         }
 206         return true;
 207 }
 208
 209 STATIC bool
 210 xfs_dquot_buf_verify(
 211         struct xfs_mount        *mp,
 212         struct xfs_buf          *bp,
 213         int                     warn)
 214 {
 215         struct xfs_dqblk        *d = (struct xfs_dqblk *)bp->b_addr;
 216         xfs_dqid_t              id = 0;
 217         int                     ndquots;
 218         int                     i;
 219
 220         /*
 221          * if we are in log recovery, the quota subsystem has not been
 222          * initialised so we have no quotainfo structure. In that case, we need
 223          * to manually calculate the number of dquots in the buffer.
 224          */
 225         if (mp->m_quotainfo)
 226                 ndquots = mp->m_quotainfo->qi_dqperchunk;
 227         else
 228                 ndquots = xfs_calc_dquots_per_chunk(bp->b_length);
 229
 230         /*
 231          * On the first read of the buffer, verify that each dquot is valid.
 232          * We don't know what the id of the dquot is supposed to be, just that
 233          * they should be increasing monotonically within the buffer. If the
 234          * first id is corrupt, then it will fail on the second dquot in the
 235          * buffer so corruptions could point to the wrong dquot in this case.
 236          */
 237         for (i = 0; i < ndquots; i++) {
 238                 struct xfs_disk_dquot   *ddq;
 239                 int                     error;
 240
 241                 ddq = &d[i].dd_diskdq;
 242
 243                 if (i == 0)
 244                         id = be32_to_cpu(ddq->d_id);
 245
 246                 error = xfs_dqcheck(mp, ddq, id + i, 0, warn, __func__);
 247                 if (error)
 248                         return false;
 249         }
 250         return true;
 251 }
 252
 253 static void
 254 xfs_dquot_buf_read_verify(
 255         struct xfs_buf  *bp)
 256 {
 257         struct xfs_mount        *mp = bp->b_target->bt_mount;
 258
 259         if (!xfs_dquot_buf_verify_crc(mp, bp))
 260                 xfs_buf_ioerror(bp, EFSBADCRC);
 261         else if (!xfs_dquot_buf_verify(mp, bp, XFS_QMOPT_DOWARN))
 262                 xfs_buf_ioerror(bp, EFSCORRUPTED);
 263
 264         if (bp->b_error)
 265                 xfs_verifier_error(bp);
 266 }
 267
 268 /*
 269  * readahead errors are silent and simply leave the buffer as !done so a real
 270  * read will then be run with the xfs_dquot_buf_ops verifier. See
 271  * xfs_inode_buf_verify() for why we use EIO and ~XBF_DONE here rather than
 272  * reporting the failure.
 273  */
 274 static void
 275 xfs_dquot_buf_readahead_verify(
 276         struct xfs_buf  *bp)
 277 {
 278         struct xfs_mount        *mp = bp->b_target->bt_mount;
 279
 280         if (!xfs_dquot_buf_verify_crc(mp, bp) ||
 281             !xfs_dquot_buf_verify(mp, bp, 0)) {
 282                 xfs_buf_ioerror(bp, -EIO);
 283                 bp->b_flags &= ~XBF_DONE;
 284         }
 285 }
 286
 287 /*
 288  * we don't calculate the CRC here as that is done when the dquot is flushed to
 289  * the buffer after the update is done. This ensures that the dquot in the
 290  * buffer always has an up-to-date CRC value.
 291  */
 292 static void
 293 xfs_dquot_buf_write_verify(
 294         struct xfs_buf  *bp)
 295 {
 296         struct xfs_mount        *mp = bp->b_target->bt_mount;
 297
 298         if (!xfs_dquot_buf_verify(mp, bp, XFS_QMOPT_DOWARN)) {
 299                 xfs_buf_ioerror(bp, EFSCORRUPTED);
 300                 xfs_verifier_error(bp);
 301                 return;
 302         }
 303 }
 304
 305 const struct xfs_buf_ops xfs_dquot_buf_ops = {
 306         .verify_read = xfs_dquot_buf_read_verify,
 307         .verify_write = xfs_dquot_buf_write_verify,
 308 };
 309
 310 const struct xfs_buf_ops xfs_dquot_buf_ra_ops = {
 311         .verify_read = xfs_dquot_buf_readahead_verify,
 312         .verify_write = xfs_dquot_buf_write_verify,
 313 };