fs/xfs/libxfs/xfs_dquot_buf.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Copyright (c) 2000-2006 Silicon Graphics, Inc.
   4  * Copyright (c) 2013 Red Hat, Inc.
   5  * All Rights Reserved.
   6  */
   7 #include "xfs.h"
   8 #include "xfs_fs.h"
   9 #include "xfs_shared.h"
  10 #include "xfs_format.h"
  11 #include "xfs_log_format.h"
  12 #include "xfs_trans_resv.h"
  13 #include "xfs_mount.h"
  14 #include "xfs_inode.h"
  15 #include "xfs_quota.h"
  16 #include "xfs_trans.h"
  17 #include "xfs_qm.h"
  18 #include "xfs_error.h"
  19
  20 int
  21 xfs_calc_dquots_per_chunk(
  22         unsigned int            nbblks) /* basic block units */
  23 {
  24         ASSERT(nbblks > 0);
  25         return BBTOB(nbblks) / sizeof(xfs_dqblk_t);
  26 }
  27
  28 /*
  29  * Do some primitive error checking on ondisk dquot data structures.
  30  *
  31  * The xfs_dqblk structure /contains/ the xfs_disk_dquot structure;
  32  * we verify them separately because at some points we have only the
  33  * smaller xfs_disk_dquot structure available.
  34  */
  35
  36 xfs_failaddr_t
  37 xfs_dquot_verify(
  38         struct xfs_mount        *mp,
  39         struct xfs_disk_dquot   *ddq,
  40         xfs_dqid_t              id)     /* used only during quotacheck */
  41 {
  42         __u8                    ddq_type;
  43
  44         /*
  45          * We can encounter an uninitialized dquot buffer for 2 reasons:
  46          * 1. If we crash while deleting the quotainode(s), and those blks got
  47          *    used for user data. This is because we take the path of regular
  48          *    file deletion; however, the size field of quotainodes is never
  49          *    updated, so all the tricks that we play in itruncate_finish
  50          *    don't quite matter.
  51          *
  52          * 2. We don't play the quota buffers when there's a quotaoff logitem.
  53          *    But the allocation will be replayed so we'll end up with an
  54          *    uninitialized quota block.
  55          *
  56          * This is all fine; things are still consistent, and we haven't lost
  57          * any quota information. Just don't complain about bad dquot blks.
  58          */
  59         if (ddq->d_magic != cpu_to_be16(XFS_DQUOT_MAGIC))
  60                 return __this_address;
  61         if (ddq->d_version != XFS_DQUOT_VERSION)
  62                 return __this_address;
  63
  64         if (ddq->d_type & ~XFS_DQTYPE_ANY)
  65                 return __this_address;
  66         ddq_type = ddq->d_type & XFS_DQTYPE_REC_MASK;
  67         if (ddq_type != XFS_DQTYPE_USER &&
  68             ddq_type != XFS_DQTYPE_PROJ &&
  69             ddq_type != XFS_DQTYPE_GROUP)
  70                 return __this_address;
  71
  72         if ((ddq->d_type & XFS_DQTYPE_BIGTIME) &&
  73             !xfs_sb_version_hasbigtime(&mp->m_sb))
  74                 return __this_address;
  75
  76         if ((ddq->d_type & XFS_DQTYPE_BIGTIME) && !ddq->d_id)
  77                 return __this_address;
  78
  79         if (id != -1 && id != be32_to_cpu(ddq->d_id))
  80                 return __this_address;
  81
  82         if (!ddq->d_id)
  83                 return NULL;
  84
  85         if (ddq->d_blk_softlimit &&
  86             be64_to_cpu(ddq->d_bcount) > be64_to_cpu(ddq->d_blk_softlimit) &&
  87             !ddq->d_btimer)
  88                 return __this_address;
  89
  90         if (ddq->d_ino_softlimit &&
  91             be64_to_cpu(ddq->d_icount) > be64_to_cpu(ddq->d_ino_softlimit) &&
  92             !ddq->d_itimer)
  93                 return __this_address;
  94
  95         if (ddq->d_rtb_softlimit &&
  96             be64_to_cpu(ddq->d_rtbcount) > be64_to_cpu(ddq->d_rtb_softlimit) &&
  97             !ddq->d_rtbtimer)
  98                 return __this_address;
  99
 100         return NULL;
 101 }
 102
 103 xfs_failaddr_t
 104 xfs_dqblk_verify(
 105         struct xfs_mount        *mp,
 106         struct xfs_dqblk        *dqb,
 107         xfs_dqid_t              id)     /* used only during quotacheck */
 108 {
 109         if (xfs_sb_version_hascrc(&mp->m_sb) &&
 110             !uuid_equal(&dqb->dd_uuid, &mp->m_sb.sb_meta_uuid))
 111                 return __this_address;
 112
 113         return xfs_dquot_verify(mp, &dqb->dd_diskdq, id);
 114 }
 115
 116 /*
 117  * Do some primitive error checking on ondisk dquot data structures.
 118  */
 119 void
 120 xfs_dqblk_repair(
 121         struct xfs_mount        *mp,
 122         struct xfs_dqblk        *dqb,
 123         xfs_dqid_t              id,
 124         xfs_dqtype_t            type)
 125 {
 126         /*
 127          * Typically, a repair is only requested by quotacheck.
 128          */
 129         ASSERT(id != -1);
 130         memset(dqb, 0, sizeof(xfs_dqblk_t));
 131
 132         dqb->dd_diskdq.d_magic = cpu_to_be16(XFS_DQUOT_MAGIC);
 133         dqb->dd_diskdq.d_version = XFS_DQUOT_VERSION;
 134         dqb->dd_diskdq.d_type = type;
 135         dqb->dd_diskdq.d_id = cpu_to_be32(id);
 136
 137         if (xfs_sb_version_hascrc(&mp->m_sb)) {
 138                 uuid_copy(&dqb->dd_uuid, &mp->m_sb.sb_meta_uuid);
 139                 xfs_update_cksum((char *)dqb, sizeof(struct xfs_dqblk),
 140                                  XFS_DQUOT_CRC_OFF);
 141         }
 142 }
 143
 144 STATIC bool
 145 xfs_dquot_buf_verify_crc(
 146         struct xfs_mount        *mp,
 147         struct xfs_buf          *bp,
 148         bool                    readahead)
 149 {
 150         struct xfs_dqblk        *d = (struct xfs_dqblk *)bp->b_addr;
 151         int                     ndquots;
 152         int                     i;
 153
 154         if (!xfs_sb_version_hascrc(&mp->m_sb))
 155                 return true;
 156
 157         /*
 158          * if we are in log recovery, the quota subsystem has not been
 159          * initialised so we have no quotainfo structure. In that case, we need
 160          * to manually calculate the number of dquots in the buffer.
 161          */
 162         if (mp->m_quotainfo)
 163                 ndquots = mp->m_quotainfo->qi_dqperchunk;
 164         else
 165                 ndquots = xfs_calc_dquots_per_chunk(bp->b_length);
 166
 167         for (i = 0; i < ndquots; i++, d++) {
 168                 if (!xfs_verify_cksum((char *)d, sizeof(struct xfs_dqblk),
 169                                  XFS_DQUOT_CRC_OFF)) {
 170                         if (!readahead)
 171                                 xfs_buf_verifier_error(bp, -EFSBADCRC, __func__,
 172                                         d, sizeof(*d), __this_address);
 173                         return false;
 174                 }
 175         }
 176         return true;
 177 }
 178
 179 STATIC xfs_failaddr_t
 180 xfs_dquot_buf_verify(
 181         struct xfs_mount        *mp,
 182         struct xfs_buf          *bp,
 183         bool                    readahead)
 184 {
 185         struct xfs_dqblk        *dqb = bp->b_addr;
 186         xfs_failaddr_t          fa;
 187         xfs_dqid_t              id = 0;
 188         int                     ndquots;
 189         int                     i;
 190
 191         /*
 192          * if we are in log recovery, the quota subsystem has not been
 193          * initialised so we have no quotainfo structure. In that case, we need
 194          * to manually calculate the number of dquots in the buffer.
 195          */
 196         if (mp->m_quotainfo)
 197                 ndquots = mp->m_quotainfo->qi_dqperchunk;
 198         else
 199                 ndquots = xfs_calc_dquots_per_chunk(bp->b_length);
 200
 201         /*
 202          * On the first read of the buffer, verify that each dquot is valid.
 203          * We don't know what the id of the dquot is supposed to be, just that
 204          * they should be increasing monotonically within the buffer. If the
 205          * first id is corrupt, then it will fail on the second dquot in the
 206          * buffer so corruptions could point to the wrong dquot in this case.
 207          */
 208         for (i = 0; i < ndquots; i++) {
 209                 struct xfs_disk_dquot   *ddq;
 210
 211                 ddq = &dqb[i].dd_diskdq;
 212
 213                 if (i == 0)
 214                         id = be32_to_cpu(ddq->d_id);
 215
 216                 fa = xfs_dqblk_verify(mp, &dqb[i], id + i);
 217                 if (fa) {
 218                         if (!readahead)
 219                                 xfs_buf_verifier_error(bp, -EFSCORRUPTED,
 220                                         __func__, &dqb[i],
 221                                         sizeof(struct xfs_dqblk), fa);
 222                         return fa;
 223                 }
 224         }
 225
 226         return NULL;
 227 }
 228
 229 static xfs_failaddr_t
 230 xfs_dquot_buf_verify_struct(
 231         struct xfs_buf          *bp)
 232 {
 233         struct xfs_mount        *mp = bp->b_mount;
 234
 235         return xfs_dquot_buf_verify(mp, bp, false);
 236 }
 237
 238 static void
 239 xfs_dquot_buf_read_verify(
 240         struct xfs_buf          *bp)
 241 {
 242         struct xfs_mount        *mp = bp->b_mount;
 243
 244         if (!xfs_dquot_buf_verify_crc(mp, bp, false))
 245                 return;
 246         xfs_dquot_buf_verify(mp, bp, false);
 247 }
 248
 249 /*
 250  * readahead errors are silent and simply leave the buffer as !done so a real
 251  * read will then be run with the xfs_dquot_buf_ops verifier. See
 252  * xfs_inode_buf_verify() for why we use EIO and ~XBF_DONE here rather than
 253  * reporting the failure.
 254  */
 255 static void
 256 xfs_dquot_buf_readahead_verify(
 257         struct xfs_buf  *bp)
 258 {
 259         struct xfs_mount        *mp = bp->b_mount;
 260
 261         if (!xfs_dquot_buf_verify_crc(mp, bp, true) ||
 262             xfs_dquot_buf_verify(mp, bp, true) != NULL) {
 263                 xfs_buf_ioerror(bp, -EIO);
 264                 bp->b_flags &= ~XBF_DONE;
 265         }
 266 }
 267
 268 /*
 269  * we don't calculate the CRC here as that is done when the dquot is flushed to
 270  * the buffer after the update is done. This ensures that the dquot in the
 271  * buffer always has an up-to-date CRC value.
 272  */
 273 static void
 274 xfs_dquot_buf_write_verify(
 275         struct xfs_buf          *bp)
 276 {
 277         struct xfs_mount        *mp = bp->b_mount;
 278
 279         xfs_dquot_buf_verify(mp, bp, false);
 280 }
 281
 282 const struct xfs_buf_ops xfs_dquot_buf_ops = {
 283         .name = "xfs_dquot",
 284         .magic16 = { cpu_to_be16(XFS_DQUOT_MAGIC),
 285                      cpu_to_be16(XFS_DQUOT_MAGIC) },
 286         .verify_read = xfs_dquot_buf_read_verify,
 287         .verify_write = xfs_dquot_buf_write_verify,
 288         .verify_struct = xfs_dquot_buf_verify_struct,
 289 };
 290
 291 const struct xfs_buf_ops xfs_dquot_buf_ra_ops = {
 292         .name = "xfs_dquot_ra",
 293         .magic16 = { cpu_to_be16(XFS_DQUOT_MAGIC),
 294                      cpu_to_be16(XFS_DQUOT_MAGIC) },
 295         .verify_read = xfs_dquot_buf_readahead_verify,
 296         .verify_write = xfs_dquot_buf_write_verify,
 297 };
 298
 299 /* Convert an on-disk timer value into an incore timer value. */
 300 time64_t
 301 xfs_dquot_from_disk_ts(
 302         struct xfs_disk_dquot   *ddq,
 303         __be32                  dtimer)
 304 {
 305         uint32_t                t = be32_to_cpu(dtimer);
 306
 307         if (t != 0 && (ddq->d_type & XFS_DQTYPE_BIGTIME))
 308                 return xfs_dq_bigtime_to_unix(t);
 309
 310         return t;
 311 }
 312
 313 /* Convert an incore timer value into an on-disk timer value. */
 314 __be32
 315 xfs_dquot_to_disk_ts(
 316         struct xfs_dquot        *dqp,
 317         time64_t                timer)
 318 {
 319         uint32_t                t = timer;
 320
 321         if (timer != 0 && (dqp->q_type & XFS_DQTYPE_BIGTIME))
 322                 t = xfs_dq_unix_to_bigtime(timer);
 323
 324         return cpu_to_be32(t);
 325 }