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         struct xfs_mount        *mp,
  39         unsigned int            nbblks) /* basic block units */
  40 {
  41         unsigned int    ndquots;
  42
  43         ASSERT(nbblks > 0);
  44         ndquots = BBTOB(nbblks);
  45         do_div(ndquots, sizeof(xfs_dqblk_t));
  46
  47         return ndquots;
  48 }
  49
  50 /*
  51  * Do some primitive error checking on ondisk dquot data structures.
  52  */
  53 int
  54 xfs_dqcheck(
  55         struct xfs_mount *mp,
  56         xfs_disk_dquot_t *ddq,
  57         xfs_dqid_t       id,
  58         uint             type,    /* used only when IO_dorepair is true */
  59         uint             flags,
  60         char             *str)
  61 {
  62         xfs_dqblk_t      *d = (xfs_dqblk_t *)ddq;
  63         int             errs = 0;
  64
  65         /*
  66          * We can encounter an uninitialized dquot buffer for 2 reasons:
  67          * 1. If we crash while deleting the quotainode(s), and those blks got
  68          *    used for user data. This is because we take the path of regular
  69          *    file deletion; however, the size field of quotainodes is never
  70          *    updated, so all the tricks that we play in itruncate_finish
  71          *    don't quite matter.
  72          *
  73          * 2. We don't play the quota buffers when there's a quotaoff logitem.
  74          *    But the allocation will be replayed so we'll end up with an
  75          *    uninitialized quota block.
  76          *
  77          * This is all fine; things are still consistent, and we haven't lost
  78          * any quota information. Just don't complain about bad dquot blks.
  79          */
  80         if (ddq->d_magic != cpu_to_be16(XFS_DQUOT_MAGIC)) {
  81                 if (flags & XFS_QMOPT_DOWARN)
  82                         xfs_alert(mp,
  83                         "%s : XFS dquot ID 0x%x, magic 0x%x != 0x%x",
  84                         str, id, be16_to_cpu(ddq->d_magic), XFS_DQUOT_MAGIC);
  85                 errs++;
  86         }
  87         if (ddq->d_version != XFS_DQUOT_VERSION) {
  88                 if (flags & XFS_QMOPT_DOWARN)
  89                         xfs_alert(mp,
  90                         "%s : XFS dquot ID 0x%x, version 0x%x != 0x%x",
  91                         str, id, ddq->d_version, XFS_DQUOT_VERSION);
  92                 errs++;
  93         }
  94
  95         if (ddq->d_flags != XFS_DQ_USER &&
  96             ddq->d_flags != XFS_DQ_PROJ &&
  97             ddq->d_flags != XFS_DQ_GROUP) {
  98                 if (flags & XFS_QMOPT_DOWARN)
  99                         xfs_alert(mp,
 100                         "%s : XFS dquot ID 0x%x, unknown flags 0x%x",
 101                         str, id, ddq->d_flags);
 102                 errs++;
 103         }
 104
 105         if (id != -1 && id != be32_to_cpu(ddq->d_id)) {
 106                 if (flags & XFS_QMOPT_DOWARN)
 107                         xfs_alert(mp,
 108                         "%s : ondisk-dquot 0x%p, ID mismatch: "
 109                         "0x%x expected, found id 0x%x",
 110                         str, ddq, id, be32_to_cpu(ddq->d_id));
 111                 errs++;
 112         }
 113
 114         if (!errs && ddq->d_id) {
 115                 if (ddq->d_blk_softlimit &&
 116                     be64_to_cpu(ddq->d_bcount) >
 117                                 be64_to_cpu(ddq->d_blk_softlimit)) {
 118                         if (!ddq->d_btimer) {
 119                                 if (flags & XFS_QMOPT_DOWARN)
 120                                         xfs_alert(mp,
 121                         "%s : Dquot ID 0x%x (0x%p) BLK TIMER NOT STARTED",
 122                                         str, (int)be32_to_cpu(ddq->d_id), ddq);
 123                                 errs++;
 124                         }
 125                 }
 126                 if (ddq->d_ino_softlimit &&
 127                     be64_to_cpu(ddq->d_icount) >
 128                                 be64_to_cpu(ddq->d_ino_softlimit)) {
 129                         if (!ddq->d_itimer) {
 130                                 if (flags & XFS_QMOPT_DOWARN)
 131                                         xfs_alert(mp,
 132                         "%s : Dquot ID 0x%x (0x%p) INODE TIMER NOT STARTED",
 133                                         str, (int)be32_to_cpu(ddq->d_id), ddq);
 134                                 errs++;
 135                         }
 136                 }
 137                 if (ddq->d_rtb_softlimit &&
 138                     be64_to_cpu(ddq->d_rtbcount) >
 139                                 be64_to_cpu(ddq->d_rtb_softlimit)) {
 140                         if (!ddq->d_rtbtimer) {
 141                                 if (flags & XFS_QMOPT_DOWARN)
 142                                         xfs_alert(mp,
 143                         "%s : Dquot ID 0x%x (0x%p) RTBLK TIMER NOT STARTED",
 144                                         str, (int)be32_to_cpu(ddq->d_id), ddq);
 145                                 errs++;
 146                         }
 147                 }
 148         }
 149
 150         if (!errs || !(flags & XFS_QMOPT_DQREPAIR))
 151                 return errs;
 152
 153         if (flags & XFS_QMOPT_DOWARN)
 154                 xfs_notice(mp, "Re-initializing dquot ID 0x%x", id);
 155
 156         /*
 157          * Typically, a repair is only requested by quotacheck.
 158          */
 159         ASSERT(id != -1);
 160         ASSERT(flags & XFS_QMOPT_DQREPAIR);
 161         memset(d, 0, sizeof(xfs_dqblk_t));
 162
 163         d->dd_diskdq.d_magic = cpu_to_be16(XFS_DQUOT_MAGIC);
 164         d->dd_diskdq.d_version = XFS_DQUOT_VERSION;
 165         d->dd_diskdq.d_flags = type;
 166         d->dd_diskdq.d_id = cpu_to_be32(id);
 167
 168         if (xfs_sb_version_hascrc(&mp->m_sb)) {
 169                 uuid_copy(&d->dd_uuid, &mp->m_sb.sb_uuid);
 170                 xfs_update_cksum((char *)d, sizeof(struct xfs_dqblk),
 171                                  XFS_DQUOT_CRC_OFF);
 172         }
 173
 174         return errs;
 175 }
 176
 177 STATIC bool
 178 xfs_dquot_buf_verify_crc(
 179         struct xfs_mount        *mp,
 180         struct xfs_buf          *bp)
 181 {
 182         struct xfs_dqblk        *d = (struct xfs_dqblk *)bp->b_addr;
 183         int                     ndquots;
 184         int                     i;
 185
 186         if (!xfs_sb_version_hascrc(&mp->m_sb))
 187                 return true;
 188
 189         /*
 190          * if we are in log recovery, the quota subsystem has not been
 191          * initialised so we have no quotainfo structure. In that case, we need
 192          * to manually calculate the number of dquots in the buffer.
 193          */
 194         if (mp->m_quotainfo)
 195                 ndquots = mp->m_quotainfo->qi_dqperchunk;
 196         else
 197                 ndquots = xfs_calc_dquots_per_chunk(mp,
 198                                         XFS_BB_TO_FSB(mp, bp->b_length));
 199
 200         for (i = 0; i < ndquots; i++, d++) {
 201                 if (!xfs_verify_cksum((char *)d, sizeof(struct xfs_dqblk),
 202                                  XFS_DQUOT_CRC_OFF))
 203                         return false;
 204                 if (!uuid_equal(&d->dd_uuid, &mp->m_sb.sb_uuid))
 205                         return false;
 206         }
 207         return true;
 208 }
 209
 210 STATIC bool
 211 xfs_dquot_buf_verify(
 212         struct xfs_mount        *mp,
 213         struct xfs_buf          *bp)
 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(mp, 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, XFS_QMOPT_DOWARN,
 247                                        "xfs_dquot_buf_verify");
 248                 if (error)
 249                         return false;
 250         }
 251         return true;
 252 }
 253
 254 static void
 255 xfs_dquot_buf_read_verify(
 256         struct xfs_buf  *bp)
 257 {
 258         struct xfs_mount        *mp = bp->b_target->bt_mount;
 259
 260         if (!xfs_dquot_buf_verify_crc(mp, bp) || !xfs_dquot_buf_verify(mp, bp)) {
 261                 XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp, bp->b_addr);
 262                 xfs_buf_ioerror(bp, EFSCORRUPTED);
 263         }
 264 }
 265
 266 /*
 267  * we don't calculate the CRC here as that is done when the dquot is flushed to
 268  * the buffer after the update is done. This ensures that the dquot in the
 269  * buffer always has an up-to-date CRC value.
 270  */
 271 static void
 272 xfs_dquot_buf_write_verify(
 273         struct xfs_buf  *bp)
 274 {
 275         struct xfs_mount        *mp = bp->b_target->bt_mount;
 276
 277         if (!xfs_dquot_buf_verify(mp, bp)) {
 278                 XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp, bp->b_addr);
 279                 xfs_buf_ioerror(bp, EFSCORRUPTED);
 280                 return;
 281         }
 282 }
 283
 284 const struct xfs_buf_ops xfs_dquot_buf_ops = {
 285         .verify_read = xfs_dquot_buf_read_verify,
 286         .verify_write = xfs_dquot_buf_write_verify,
 287 };
 288