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