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
  21 /*
  22  * XXX: kernel implementation causes ndquots calc to go real
  23  * bad. Just leaving the existing userspace calc here right now.
  24  */
  25 int
  26 xfs_calc_dquots_per_chunk(
  27         unsigned int            nbblks) /* basic block units */
  28 {
  29
  30         ASSERT(nbblks > 0);
  31         return BBTOB(nbblks) / sizeof(xfs_dqblk_t);
  32
  33 #if 0   /* kernel code that goes wrong in userspace! */
  34         unsigned int    ndquots;
  35
  36         ASSERT(nbblks > 0);
  37         ndquots = BBTOB(nbblks);
  38         do_div(ndquots, sizeof(xfs_dqblk_t));
  39
  40         return ndquots;
  41 #endif
  42 }
  43
  44 /*
  45  * Do some primitive error checking on ondisk dquot data structures.
  46  */
  47 int
  48 xfs_dqcheck(
  49         struct xfs_mount *mp,
  50         xfs_disk_dquot_t *ddq,
  51         xfs_dqid_t       id,
  52         uint             type,    /* used only when IO_dorepair is true */
  53         uint             flags,
  54         char             *str)
  55 {
  56         xfs_dqblk_t      *d = (xfs_dqblk_t *)ddq;
  57         int             errs = 0;
  58
  59         /*
  60          * We can encounter an uninitialized dquot buffer for 2 reasons:
  61          * 1. If we crash while deleting the quotainode(s), and those blks got
  62          *    used for user data. This is because we take the path of regular
  63          *    file deletion; however, the size field of quotainodes is never
  64          *    updated, so all the tricks that we play in itruncate_finish
  65          *    don't quite matter.
  66          *
  67          * 2. We don't play the quota buffers when there's a quotaoff logitem.
  68          *    But the allocation will be replayed so we'll end up with an
  69          *    uninitialized quota block.
  70          *
  71          * This is all fine; things are still consistent, and we haven't lost
  72          * any quota information. Just don't complain about bad dquot blks.
  73          */
  74         if (ddq->d_magic != cpu_to_be16(XFS_DQUOT_MAGIC)) {
  75                 if (flags & XFS_QMOPT_DOWARN)
  76                         xfs_alert(mp,
  77                         "%s : XFS dquot ID 0x%x, magic 0x%x != 0x%x",
  78                         str, id, be16_to_cpu(ddq->d_magic), XFS_DQUOT_MAGIC);
  79                 errs++;
  80         }
  81         if (ddq->d_version != XFS_DQUOT_VERSION) {
  82                 if (flags & XFS_QMOPT_DOWARN)
  83                         xfs_alert(mp,
  84                         "%s : XFS dquot ID 0x%x, version 0x%x != 0x%x",
  85                         str, id, ddq->d_version, XFS_DQUOT_VERSION);
  86                 errs++;
  87         }
  88
  89         if (ddq->d_flags != XFS_DQ_USER &&
  90             ddq->d_flags != XFS_DQ_PROJ &&
  91             ddq->d_flags != XFS_DQ_GROUP) {
  92                 if (flags & XFS_QMOPT_DOWARN)
  93                         xfs_alert(mp,
  94                         "%s : XFS dquot ID 0x%x, unknown flags 0x%x",
  95                         str, id, ddq->d_flags);
  96                 errs++;
  97         }
  98
  99         if (id != -1 && id != be32_to_cpu(ddq->d_id)) {
 100                 if (flags & XFS_QMOPT_DOWARN)
 101                         xfs_alert(mp,
 102                         "%s : ondisk-dquot 0x%p, ID mismatch: "
 103                         "0x%x expected, found id 0x%x",
 104                         str, ddq, id, be32_to_cpu(ddq->d_id));
 105                 errs++;
 106         }
 107
 108         if (!errs && ddq->d_id) {
 109                 if (ddq->d_blk_softlimit &&
 110                     be64_to_cpu(ddq->d_bcount) >
 111                                 be64_to_cpu(ddq->d_blk_softlimit)) {
 112                         if (!ddq->d_btimer) {
 113                                 if (flags & XFS_QMOPT_DOWARN)
 114                                         xfs_alert(mp,
 115                         "%s : Dquot ID 0x%x (0x%p) BLK TIMER NOT STARTED",
 116                                         str, (int)be32_to_cpu(ddq->d_id), ddq);
 117                                 errs++;
 118                         }
 119                 }
 120                 if (ddq->d_ino_softlimit &&
 121                     be64_to_cpu(ddq->d_icount) >
 122                                 be64_to_cpu(ddq->d_ino_softlimit)) {
 123                         if (!ddq->d_itimer) {
 124                                 if (flags & XFS_QMOPT_DOWARN)
 125                                         xfs_alert(mp,
 126                         "%s : Dquot ID 0x%x (0x%p) INODE TIMER NOT STARTED",
 127                                         str, (int)be32_to_cpu(ddq->d_id), ddq);
 128                                 errs++;
 129                         }
 130                 }
 131                 if (ddq->d_rtb_softlimit &&
 132                     be64_to_cpu(ddq->d_rtbcount) >
 133                                 be64_to_cpu(ddq->d_rtb_softlimit)) {
 134                         if (!ddq->d_rtbtimer) {
 135                                 if (flags & XFS_QMOPT_DOWARN)
 136                                         xfs_alert(mp,
 137                         "%s : Dquot ID 0x%x (0x%p) RTBLK TIMER NOT STARTED",
 138                                         str, (int)be32_to_cpu(ddq->d_id), ddq);
 139                                 errs++;
 140                         }
 141                 }
 142         }
 143
 144         if (!errs || !(flags & XFS_QMOPT_DQREPAIR))
 145                 return errs;
 146
 147         if (flags & XFS_QMOPT_DOWARN)
 148                 xfs_notice(mp, "Re-initializing dquot ID 0x%x", id);
 149
 150         /*
 151          * Typically, a repair is only requested by quotacheck.
 152          */
 153         ASSERT(id != -1);
 154         ASSERT(flags & XFS_QMOPT_DQREPAIR);
 155         memset(d, 0, sizeof(xfs_dqblk_t));
 156
 157         d->dd_diskdq.d_magic = cpu_to_be16(XFS_DQUOT_MAGIC);
 158         d->dd_diskdq.d_version = XFS_DQUOT_VERSION;
 159         d->dd_diskdq.d_flags = type;
 160         d->dd_diskdq.d_id = cpu_to_be32(id);
 161
 162         if (xfs_sb_version_hascrc(&mp->m_sb)) {
 163                 uuid_copy(&d->dd_uuid, &mp->m_sb.sb_uuid);
 164                 xfs_update_cksum((char *)d, sizeof(struct xfs_dqblk),
 165                                  XFS_DQUOT_CRC_OFF);
 166         }
 167
 168         return errs;
 169 }
 170
 171 STATIC bool
 172 xfs_dquot_buf_verify_crc(
 173         struct xfs_mount        *mp,
 174         struct xfs_buf          *bp)
 175 {
 176         struct xfs_dqblk        *d = (struct xfs_dqblk *)bp->b_addr;
 177         int                     ndquots;
 178         int                     i;
 179
 180         if (!xfs_sb_version_hascrc(&mp->m_sb))
 181                 return true;
 182
 183         /*
 184          * if we are in log recovery, the quota subsystem has not been
 185          * initialised so we have no quotainfo structure. In that case, we need
 186          * to manually calculate the number of dquots in the buffer.
 187          */
 188         if (mp->m_quotainfo)
 189                 ndquots = mp->m_quotainfo->qi_dqperchunk;
 190         else
 191                 ndquots = xfs_calc_dquots_per_chunk(bp->b_length);
 192 //                                      XFS_BB_TO_FSB(mp, bp->b_length));
 193
 194         for (i = 0; i < ndquots; i++, d++) {
 195                 if (!xfs_verify_cksum((char *)d, sizeof(struct xfs_dqblk),
 196                                  XFS_DQUOT_CRC_OFF))
 197                         return false;
 198                 if (!uuid_equal(&d->dd_uuid, &mp->m_sb.sb_uuid))
 199                         return false;
 200         }
 201         return true;
 202 }
 203
 204 STATIC bool
 205 xfs_dquot_buf_verify(
 206         struct xfs_mount        *mp,
 207         struct xfs_buf          *bp)
 208 {
 209         struct xfs_dqblk        *d = (struct xfs_dqblk *)bp->b_addr;
 210         xfs_dqid_t              id = 0;
 211         int                     ndquots;
 212         int                     i;
 213
 214         /*
 215          * if we are in log recovery, the quota subsystem has not been
 216          * initialised so we have no quotainfo structure. In that case, we need
 217          * to manually calculate the number of dquots in the buffer.
 218          */
 219         if (mp->m_quotainfo)
 220                 ndquots = mp->m_quotainfo->qi_dqperchunk;
 221         else
 222                 ndquots = xfs_calc_dquots_per_chunk(bp->b_length);
 223
 224         /*
 225          * On the first read of the buffer, verify that each dquot is valid.
 226          * We don't know what the id of the dquot is supposed to be, just that
 227          * they should be increasing monotonically within the buffer. If the
 228          * first id is corrupt, then it will fail on the second dquot in the
 229          * buffer so corruptions could point to the wrong dquot in this case.
 230          */
 231         for (i = 0; i < ndquots; i++) {
 232                 struct xfs_disk_dquot   *ddq;
 233                 int                     error;
 234
 235                 ddq = &d[i].dd_diskdq;
 236
 237                 if (i == 0)
 238                         id = be32_to_cpu(ddq->d_id);
 239
 240                 error = xfs_dqcheck(mp, ddq, id + i, 0, XFS_QMOPT_DOWARN,
 241                                        "xfs_dquot_buf_verify");
 242                 if (error)
 243                         return false;
 244         }
 245         return true;
 246 }
 247
 248 static void
 249 xfs_dquot_buf_read_verify(
 250         struct xfs_buf  *bp)
 251 {
 252         struct xfs_mount        *mp = bp->b_target->bt_mount;
 253
 254         if (!xfs_dquot_buf_verify_crc(mp, bp))
 255                 xfs_buf_ioerror(bp, -EFSBADCRC);
 256         else if (!xfs_dquot_buf_verify(mp, bp))
 257                 xfs_buf_ioerror(bp, -EFSCORRUPTED);
 258
 259         if (bp->b_error)
 260                 xfs_verifier_error(bp);
 261 }
 262
 263 /*
 264  * we don't calculate the CRC here as that is done when the dquot is flushed to
 265  * the buffer after the update is done. This ensures that the dquot in the
 266  * buffer always has an up-to-date CRC value.
 267  */
 268 static void
 269 xfs_dquot_buf_write_verify(
 270         struct xfs_buf  *bp)
 271 {
 272         struct xfs_mount        *mp = bp->b_target->bt_mount;
 273
 274         if (!xfs_dquot_buf_verify(mp, bp)) {
 275                 xfs_buf_ioerror(bp, -EFSCORRUPTED);
 276                 xfs_verifier_error(bp);
 277                 return;
 278         }
 279 }
 280
 281 const struct xfs_buf_ops xfs_dquot_buf_ops = {
 282         .verify_read = xfs_dquot_buf_read_verify,
 283         .verify_write = xfs_dquot_buf_write_verify,
 284 };
 285