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