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