sys/vfs/hammer2/hammer2_ondisk.c

   1 /*
   2  * Copyright (c) 2020 Tomohiro Kusumi <tkusumi@netbsd.org>
   3  * Copyright (c) 2020 The DragonFly Project
   4  * All rights reserved.
   5  *
   6  * This code is derived from software contributed to The DragonFly Project
   7  * by Matthew Dillon <dillon@dragonflybsd.org>
   8  *
   9  * Redistribution and use in source and binary forms, with or without
  10  * modification, are permitted provided that the following conditions
  11  * are met:
  12  *
  13  * 1. Redistributions of source code must retain the above copyright
  14  *    notice, this list of conditions and the following disclaimer.
  15  * 2. Redistributions in binary form must reproduce the above copyright
  16  *    notice, this list of conditions and the following disclaimer in
  17  *    the documentation and/or other materials provided with the
  18  *    distribution.
  19  * 3. Neither the name of The DragonFly Project nor the names of its
  20  *    contributors may be used to endorse or promote products derived
  21  *    from this software without specific, prior written permission.
  22  *
  23  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  24  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  25  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  26  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
  27  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
  28  * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
  29  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  30  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
  31  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  32  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
  33  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  34  * SUCH DAMAGE.
  35  */
  36 #include <sys/param.h>
  37 #include <sys/systm.h>
  38 #include <sys/kernel.h>
  39 #include <sys/queue.h>
  40 #include <sys/nlookup.h>
  41 #include <sys/vnode.h>
  42 #include <sys/mount.h>
  43 #include <sys/fcntl.h>
  44 #include <sys/buf.h>
  45 #include <sys/uuid.h>
  46 #include <sys/objcache.h>
  47
  48 #include "hammer2.h"
  49
  50 #define hprintf(X, ...) kprintf("hammer2_ondisk: " X, ## __VA_ARGS__)
  51
  52 static int
  53 hammer2_lookup_device(const char *path, int rootmount, struct vnode **devvp)
  54 {
  55         struct vnode *vp = NULL;
  56         struct nlookupdata nd;
  57         int error = 0;
  58
  59         KKASSERT(path);
  60         KKASSERT(*path != '\0');
  61
  62         if (rootmount) {
  63                 error = bdevvp(kgetdiskbyname(path), &vp);
  64                 if (error)
  65                         hprintf("cannot find %s %d\n", path, error);
  66         } else {
  67                 error = nlookup_init(&nd, path, UIO_SYSSPACE, NLC_FOLLOW);
  68                 if (error == 0)
  69                         error = nlookup(&nd);
  70                 if (error == 0)
  71                         error = cache_vref(&nd.nl_nch, nd.nl_cred, &vp);
  72                 if (error)
  73                         hprintf("failed to nlookup %s %d\n", path, error);
  74                 nlookup_done(&nd);
  75         }
  76
  77         if (error == 0) {
  78                 KKASSERT(vp);
  79                 if (!vn_isdisk(vp, &error)) {
  80                         KKASSERT(error);
  81                         hprintf("%s not a block device %d\n", path, error);
  82                 }
  83         }
  84
  85         if (error && vp) {
  86                 vrele(vp);
  87                 vp = NULL;
  88         }
  89
  90         *devvp = vp;
  91         return error;
  92 }
  93
  94 int
  95 hammer2_open_devvp(const hammer2_devvp_list_t *devvpl, int ronly)
  96 {
  97         hammer2_devvp_t *e;
  98         struct vnode *devvp;
  99         const char *path;
 100         int count, error;
 101
 102         TAILQ_FOREACH(e, devvpl, entry) {
 103                 devvp = e->devvp;
 104                 path = e->path;
 105                 KKASSERT(devvp);
 106                 count = vcount(devvp);
 107                 if (count > 0) {
 108                         hprintf("%s already has %d references\n", path, count);
 109                         return EBUSY;
 110                 }
 111                 vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY);
 112                 error = vinvalbuf(devvp, V_SAVE, 0, 0);
 113                 if (error == 0) {
 114                         KKASSERT(!e->open);
 115                         error = VOP_OPEN(devvp,
 116                                          (ronly ? FREAD : FREAD | FWRITE),
 117                                          FSCRED, NULL);
 118                         if (error == 0)
 119                                 e->open = 1;
 120                         else
 121                                 hprintf("failed to open %s %d\n", path, error);
 122                 }
 123                 vn_unlock(devvp);
 124                 if (error)
 125                         return error;
 126                 KKASSERT(e->open);
 127         }
 128
 129         return 0;
 130 }
 131
 132 int
 133 hammer2_close_devvp(const hammer2_devvp_list_t *devvpl, int ronly)
 134 {
 135         hammer2_devvp_t *e;
 136         struct vnode *devvp;
 137
 138         TAILQ_FOREACH(e, devvpl, entry) {
 139                 devvp = e->devvp;
 140                 KKASSERT(devvp);
 141                 if (e->open) {
 142                         vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY);
 143                         vinvalbuf(devvp, (ronly ? 0 : V_SAVE), 0, 0);
 144                         VOP_CLOSE(devvp, (ronly ? FREAD : FREAD|FWRITE), NULL);
 145                         vn_unlock(devvp);
 146                         e->open = 0;
 147                 }
 148         }
 149
 150         return 0;
 151 }
 152
 153 int
 154 hammer2_init_devvp(const char *blkdevs, int rootmount,
 155                    hammer2_devvp_list_t *devvpl)
 156 {
 157         hammer2_devvp_t *e;
 158         struct vnode *devvp;
 159         const char *p;
 160         char *path;
 161         int i, error = 0;
 162
 163         KKASSERT(TAILQ_EMPTY(devvpl));
 164         KKASSERT(blkdevs); /* could be empty string */
 165         p = blkdevs;
 166
 167         path = objcache_get(namei_oc, M_WAITOK);
 168         while (1) {
 169                 strcpy(path, "");
 170                 if (*p != '/') {
 171                         strcpy(path, "/dev/"); /* relative path */
 172                 }
 173                 /* scan beyond "/dev/" */
 174                 for (i = strlen(path); i < MAXPATHLEN-1; ++i) {
 175                         if (*p == '\0') {
 176                                 break;
 177                         } else if (*p == ':') {
 178                                 p++;
 179                                 break;
 180                         } else {
 181                                 path[i] = *p;
 182                                 p++;
 183                         }
 184                 }
 185                 path[i] = '\0';
 186                 /* path shorter than "/dev/" means invalid or done */
 187                 if (strlen(path) <= strlen("/dev/")) {
 188                         if (strlen(p)) {
 189                                 hprintf("ignore incomplete path %s\n", path);
 190                                 continue;
 191                         } else {
 192                                 /* end of string */
 193                                 KKASSERT(*p == '\0');
 194                                 break;
 195                         }
 196                 }
 197                 /* lookup path from above */
 198                 KKASSERT(strncmp(path, "/dev/", 5) == 0);
 199                 devvp = NULL;
 200                 error = hammer2_lookup_device(path, rootmount, &devvp);
 201                 if (error) {
 202                         KKASSERT(!devvp);
 203                         hprintf("failed to lookup %s %d\n", path, error);
 204                         break;
 205                 }
 206                 KKASSERT(devvp);
 207                 e = kmalloc(sizeof(*e), M_HAMMER2, M_WAITOK | M_ZERO);
 208                 e->devvp = devvp;
 209                 e->path = kstrdup(path, M_HAMMER2);
 210                 TAILQ_INSERT_TAIL(devvpl, e, entry);
 211         }
 212         objcache_put(namei_oc, path);
 213
 214         return error;
 215 }
 216
 217 void
 218 hammer2_cleanup_devvp(hammer2_devvp_list_t *devvpl)
 219 {
 220         hammer2_devvp_t *e;
 221
 222         while (!TAILQ_EMPTY(devvpl)) {
 223                 e = TAILQ_FIRST(devvpl);
 224                 TAILQ_REMOVE(devvpl, e, entry);
 225                 /* devvp */
 226                 KKASSERT(e->devvp);
 227                 e->devvp->v_rdev->si_mountpoint = NULL;
 228                 vrele(e->devvp);
 229                 e->devvp = NULL;
 230                 /* path */
 231                 KKASSERT(e->path);
 232                 kfree(e->path, M_HAMMER2);
 233                 e->path = NULL;
 234                 kfree(e, M_HAMMER2);
 235         }
 236 }
 237
 238 static int
 239 hammer2_verify_volumes_common(const hammer2_volume_t *volumes)
 240 {
 241         const hammer2_volume_t *vol;
 242         struct partinfo part;
 243         const char *path;
 244         int i;
 245
 246         for (i = 0; i < HAMMER2_MAX_VOLUMES; ++i) {
 247                 vol = &volumes[i];
 248                 if (vol->id == -1)
 249                         continue;
 250                 path = vol->dev->path;
 251                 /* check volume fields are initialized */
 252                 if (!vol->dev->devvp) {
 253                         hprintf("%s has NULL devvp\n", path);
 254                         return EINVAL;
 255                 }
 256                 if (vol->offset == (hammer2_off_t)-1) {
 257                         hprintf("%s has bad offset 0x%016jx\n", path,
 258                                 (intmax_t)vol->offset);
 259                         return EINVAL;
 260                 }
 261                 if (vol->size == (hammer2_off_t)-1) {
 262                         hprintf("%s has bad size 0x%016jx\n", path,
 263                                 (intmax_t)vol->size);
 264                         return EINVAL;
 265                 }
 266                 /* check volume size vs block device size */
 267                 if (VOP_IOCTL(vol->dev->devvp, DIOCGPART, (void*)&part, 0,
 268                               curthread->td_ucred , NULL) == 0) {
 269                         if (vol->size > part.media_size) {
 270                                 hprintf("%s's size 0x%016jx exceeds device size "
 271                                         "0x%016jx\n", path, (intmax_t)vol->size,
 272                                         part.media_size);
 273                                 return EINVAL;
 274                         }
 275                 }
 276         }
 277
 278         return 0;
 279 }
 280
 281 static int
 282 hammer2_verify_volumes_1(const hammer2_volume_t *volumes,
 283                          const hammer2_volume_data_t *rootvoldata)
 284 {
 285         const hammer2_volume_t *vol;
 286         hammer2_off_t off;
 287         const char *path;
 288         int i, nvolumes = 0;
 289
 290         /* check initialized volume count */
 291         for (i = 0; i < HAMMER2_MAX_VOLUMES; ++i) {
 292                 vol = &volumes[i];
 293                 if (vol->id != -1)
 294                         nvolumes++;
 295         }
 296         if (nvolumes != 1) {
 297                 hprintf("only 1 volume supported\n");
 298                 return EINVAL;
 299         }
 300
 301         /* check volume header */
 302         if (rootvoldata->volu_id) {
 303                 hprintf("volume id %d must be 0\n", rootvoldata->volu_id);
 304                 return EINVAL;
 305         }
 306         if (rootvoldata->nvolumes) {
 307                 hprintf("volume count %d must be 0\n", rootvoldata->nvolumes);
 308                 return EINVAL;
 309         }
 310         if (rootvoldata->total_size) {
 311                 hprintf("total size 0x%016jx must be 0\n",
 312                         (intmax_t)rootvoldata->total_size);
 313                 return EINVAL;
 314         }
 315         for (i = 0; i < HAMMER2_MAX_VOLUMES; ++i) {
 316                 off = rootvoldata->volu_loff[i];
 317                 if (off) {
 318                         hprintf("volume offset[%d] 0x%016jx must be 0\n", i,
 319                                 (intmax_t)off);
 320                         return EINVAL;
 321                 }
 322         }
 323
 324         /* check volume */
 325         vol = &volumes[0];
 326         path = vol->dev->path;
 327         if (vol->id) {
 328                 hprintf("%s has non zero id %d\n", path, vol->id);
 329                 return EINVAL;
 330         }
 331         if (vol->offset) {
 332                 hprintf("%s has non zero offset 0x%016jx\n", path,
 333                         (intmax_t)vol->offset);
 334                 return EINVAL;
 335         }
 336         if (vol->size & HAMMER2_VOLUME_ALIGNMASK64) {
 337                 hprintf("%s's size is not 0x%016jx aligned\n", path,
 338                         (intmax_t)HAMMER2_VOLUME_ALIGN);
 339                 return EINVAL;
 340         }
 341
 342         return 0;
 343 }
 344
 345 static int
 346 hammer2_verify_volumes_2(const hammer2_volume_t *volumes,
 347                          const hammer2_volume_data_t *rootvoldata)
 348 {
 349         const hammer2_volume_t *vol;
 350         hammer2_off_t off, total_size = 0;
 351         const char *path;
 352         int i, nvolumes = 0;
 353
 354         /* check initialized volume count */
 355         for (i = 0; i < HAMMER2_MAX_VOLUMES; ++i) {
 356                 vol = &volumes[i];
 357                 if (vol->id != -1) {
 358                         nvolumes++;
 359                         total_size += vol->size;
 360                 }
 361         }
 362
 363         /* check volume header */
 364         if (rootvoldata->volu_id != HAMMER2_ROOT_VOLUME) {
 365                 hprintf("volume id %d must be %d\n", rootvoldata->volu_id,
 366                         HAMMER2_ROOT_VOLUME);
 367                 return EINVAL;
 368         }
 369         if (rootvoldata->nvolumes != nvolumes) {
 370                 hprintf("volume header requires %d devices, %d specified\n",
 371                         rootvoldata->nvolumes, nvolumes);
 372                 return EINVAL;
 373         }
 374         if (rootvoldata->total_size != total_size) {
 375                 hprintf("total size 0x%016jx does not equal sum of volumes 0x%016jx\n",
 376                         rootvoldata->total_size, total_size);
 377                 return EINVAL;
 378         }
 379         for (i = 0; i < nvolumes; ++i) {
 380                 off = rootvoldata->volu_loff[i];
 381                 if (off == (hammer2_off_t)-1) {
 382                         hprintf("volume offset[%d] 0x%016jx must not be -1\n",
 383                                 i, (intmax_t)off);
 384                         return EINVAL;
 385                 }
 386         }
 387         for (i = nvolumes; i < HAMMER2_MAX_VOLUMES; ++i) {
 388                 off = rootvoldata->volu_loff[i];
 389                 if (off != (hammer2_off_t)-1) {
 390                         hprintf("volume offset[%d] 0x%016jx must be -1\n",
 391                                 i, (intmax_t)off);
 392                         return EINVAL;
 393                 }
 394         }
 395
 396         /* check volumes */
 397         for (i = 0; i < HAMMER2_MAX_VOLUMES; ++i) {
 398                 vol = &volumes[i];
 399                 if (vol->id == -1)
 400                         continue;
 401                 path = vol->dev->path;
 402                 /* check offset */
 403                 if (vol->offset & HAMMER2_FREEMAP_LEVEL1_MASK) {
 404                         hprintf("%s's offset 0x%016jx not 0x%016jx aligned\n",
 405                                 path, (intmax_t)vol->offset,
 406                                 HAMMER2_FREEMAP_LEVEL1_SIZE);
 407                         return EINVAL;
 408                 }
 409                 /* check vs previous volume */
 410                 if (i) {
 411                         if (vol->id <= (vol-1)->id) {
 412                                 hprintf("%s has inconsistent id %d\n", path,
 413                                         vol->id);
 414                                 return EINVAL;
 415                         }
 416                         if (vol->offset != (vol-1)->offset + (vol-1)->size) {
 417                                 hprintf("%s has inconsistent offset 0x%016jx\n",
 418                                         path, (intmax_t)vol->offset);
 419                                 return EINVAL;
 420                         }
 421                 } else { /* first */
 422                         if (vol->offset) {
 423                                 hprintf("%s has non zero offset 0x%016jx\n",
 424                                         path, (intmax_t)vol->offset);
 425                                 return EINVAL;
 426                         }
 427                 }
 428                 /* check size for non-last and last volumes */
 429                 if (i != rootvoldata->nvolumes - 1) {
 430                         if (vol->size < HAMMER2_FREEMAP_LEVEL1_SIZE) {
 431                                 hprintf("%s's size must be >= 0x%016jx\n", path,
 432                                         (intmax_t)HAMMER2_FREEMAP_LEVEL1_SIZE);
 433                                 return EINVAL;
 434                         }
 435                         if (vol->size & HAMMER2_FREEMAP_LEVEL1_MASK) {
 436                                 hprintf("%s's size is not 0x%016jx aligned\n",
 437                                         path,
 438                                         (intmax_t)HAMMER2_FREEMAP_LEVEL1_SIZE);
 439                                 return EINVAL;
 440                         }
 441                 } else { /* last */
 442                         if (vol->size & HAMMER2_VOLUME_ALIGNMASK64) {
 443                                 hprintf("%s's size is not 0x%016jx aligned\n",
 444                                         path,
 445                                         (intmax_t)HAMMER2_VOLUME_ALIGN);
 446                                 return EINVAL;
 447                         }
 448                 }
 449         }
 450
 451         return 0;
 452 }
 453
 454 static int
 455 hammer2_verify_volumes(const hammer2_volume_t *volumes,
 456                        const hammer2_volume_data_t *rootvoldata)
 457 {
 458         int error;
 459
 460         error = hammer2_verify_volumes_common(volumes);
 461         if (error)
 462                 return error;
 463
 464         if (rootvoldata->version >= HAMMER2_VOL_VERSION_MULTI_VOLUMES)
 465                 return hammer2_verify_volumes_2(volumes, rootvoldata);
 466         else
 467                 return hammer2_verify_volumes_1(volumes, rootvoldata);
 468 }
 469
 470 /*
 471  * Returns zone# of returned volume header or < 0 on failure.
 472  */
 473 static int
 474 hammer2_read_volume_header(struct vnode *devvp, const char *path,
 475                            hammer2_volume_data_t *voldata)
 476 {
 477         hammer2_volume_data_t *vd;
 478         struct buf *bp = NULL;
 479         hammer2_crc32_t crc0, crc1;
 480         int zone = -1;
 481         int i;
 482
 483         /*
 484          * There are up to 4 copies of the volume header (syncs iterate
 485          * between them so there is no single master).  We don't trust the
 486          * volu_size field so we don't know precisely how large the filesystem
 487          * is, so depend on the OS to return an error if we go beyond the
 488          * block device's EOF.
 489          */
 490         for (i = 0; i < HAMMER2_NUM_VOLHDRS; ++i) {
 491                 if (bread(devvp, i * HAMMER2_ZONE_BYTES64, HAMMER2_VOLUME_BYTES,
 492                           &bp)) {
 493                         brelse(bp);
 494                         bp = NULL;
 495                         continue;
 496                 }
 497
 498                 vd = (struct hammer2_volume_data *)bp->b_data;
 499                 /* verify volume header magic */
 500                 if ((vd->magic != HAMMER2_VOLUME_ID_HBO) &&
 501                     (vd->magic != HAMMER2_VOLUME_ID_ABO)) {
 502                         hprintf("%s #%d: bad magic\n", path, i);
 503                         brelse(bp);
 504                         bp = NULL;
 505                         continue;
 506                 }
 507
 508                 if (vd->magic == HAMMER2_VOLUME_ID_ABO) {
 509                         /* XXX: Reversed-endianness filesystem */
 510                         hprintf("%s #%d: reverse-endian filesystem detected\n",
 511                                 path, i);
 512                         brelse(bp);
 513                         bp = NULL;
 514                         continue;
 515                 }
 516
 517                 /* verify volume header CRC's */
 518                 crc0 = vd->icrc_sects[HAMMER2_VOL_ICRC_SECT0];
 519                 crc1 = hammer2_icrc32(bp->b_data + HAMMER2_VOLUME_ICRC0_OFF,
 520                                       HAMMER2_VOLUME_ICRC0_SIZE);
 521                 if (crc0 != crc1) {
 522                         hprintf("%s #%d: volume header crc mismatch sect0 %08x/%08x\n",
 523                                 path, i, crc0, crc1);
 524                         brelse(bp);
 525                         bp = NULL;
 526                         continue;
 527                 }
 528                 crc0 = vd->icrc_sects[HAMMER2_VOL_ICRC_SECT1];
 529                 crc1 = hammer2_icrc32(bp->b_data + HAMMER2_VOLUME_ICRC1_OFF,
 530                                       HAMMER2_VOLUME_ICRC1_SIZE);
 531                 if (crc0 != crc1) {
 532                         hprintf("%s #%d: volume header crc mismatch sect1 %08x/%08x\n",
 533                                 path, i, crc0, crc1);
 534                         brelse(bp);
 535                         bp = NULL;
 536                         continue;
 537                 }
 538                 crc0 = vd->icrc_volheader;
 539                 crc1 = hammer2_icrc32(bp->b_data + HAMMER2_VOLUME_ICRCVH_OFF,
 540                                       HAMMER2_VOLUME_ICRCVH_SIZE);
 541                 if (crc0 != crc1) {
 542                         hprintf("%s #%d: volume header crc mismatch vh %08x/%08x\n",
 543                                 path, i, crc0, crc1);
 544                         brelse(bp);
 545                         bp = NULL;
 546                         continue;
 547                 }
 548
 549                 if (zone == -1 || voldata->mirror_tid < vd->mirror_tid) {
 550                         *voldata = *vd;
 551                         zone = i;
 552                 }
 553                 brelse(bp);
 554                 bp = NULL;
 555         }
 556
 557         if (zone == -1) {
 558                 hprintf("%s has no valid volume headers\n", path);
 559                 return -EINVAL;
 560         }
 561         return zone;
 562 }
 563
 564 int
 565 hammer2_init_volumes(struct mount *mp, const hammer2_devvp_list_t *devvpl,
 566                      hammer2_volume_t *volumes,
 567                      hammer2_volume_data_t *rootvoldata,
 568                      struct vnode **rootvoldevvp)
 569 {
 570         hammer2_devvp_t *e;
 571         hammer2_volume_data_t *voldata;
 572         hammer2_volume_t *vol;
 573         struct vnode *devvp;
 574         const char *path;
 575         uuid_t fsid, fstype;
 576         int i, zone, error = 0, version = -1, nvolumes = 0;
 577
 578         for (i = 0; i < HAMMER2_MAX_VOLUMES; ++i) {
 579                 vol = &volumes[i];
 580                 vol->dev = NULL;
 581                 vol->id = -1;
 582                 vol->offset = (hammer2_off_t)-1;
 583                 vol->size = (hammer2_off_t)-1;
 584         }
 585
 586         voldata = kmalloc(sizeof(*voldata), M_HAMMER2, M_WAITOK | M_ZERO);
 587         bzero(&fsid, sizeof(fsid));
 588         bzero(&fstype, sizeof(fstype));
 589         bzero(rootvoldata, sizeof(*rootvoldata));
 590
 591         TAILQ_FOREACH(e, devvpl, entry) {
 592                 devvp = e->devvp;
 593                 path = e->path;
 594                 KKASSERT(devvp);
 595
 596                 /* returns negative error or positive zone# */
 597                 error = hammer2_read_volume_header(devvp, path, voldata);
 598                 if (error < 0) {
 599                         hprintf("failed to read %s's volume header\n", path);
 600                         error = -error;
 601                         goto done;
 602                 }
 603                 zone = error;
 604                 error = 0; /* reset error */
 605
 606                 if (voldata->volu_id >= HAMMER2_MAX_VOLUMES) {
 607                         hprintf("%s has bad volume id %d\n", path,
 608                                 voldata->volu_id);
 609                         error = EINVAL;
 610                         goto done;
 611                 }
 612                 vol = &volumes[voldata->volu_id];
 613                 if (vol->id != -1) {
 614                         hprintf("%s already initialized\n", path);
 615                         error = EINVAL;
 616                         goto done;
 617                 }
 618                 /* all headers must have the same version, nvolumes and uuid */
 619                 if (version == -1) {
 620                         version = voldata->version;
 621                         nvolumes = voldata->nvolumes;
 622                         fsid = voldata->fsid;
 623                         fstype = voldata->fstype;
 624                 } else {
 625                         if (version != (int)voldata->version) {
 626                                 hprintf("volume version mismatch %d vs %d\n",
 627                                         version, (int)voldata->version);
 628                                 error = ENXIO;
 629                                 goto done;
 630                         }
 631                         if (nvolumes != voldata->nvolumes) {
 632                                 hprintf("volume count mismatch %d vs %d\n",
 633                                         nvolumes, voldata->nvolumes);
 634                                 error = ENXIO;
 635                                 goto done;
 636                         }
 637                         if (bcmp(&fsid, &voldata->fsid, sizeof(fsid))) {
 638                                 hprintf("fsid uuid mismatch\n");
 639                                 error = ENXIO;
 640                                 goto done;
 641                         }
 642                         if (bcmp(&fstype, &voldata->fstype, sizeof(fstype))) {
 643                                 hprintf("fstype uuid mismatch\n");
 644                                 error = ENXIO;
 645                                 goto done;
 646                         }
 647                 }
 648                 if (version < HAMMER2_VOL_VERSION_MIN ||
 649                     version > HAMMER2_VOL_VERSION_WIP) {
 650                         hprintf("bad volume version %d\n", version);
 651                         error = EINVAL;
 652                         goto done;
 653                 }
 654                 /* all per-volume tests passed */
 655                 vol->dev = e;
 656                 vol->id = voldata->volu_id;
 657                 vol->offset = voldata->volu_loff[vol->id];
 658                 vol->size = voldata->volu_size;
 659                 if (vol->id == HAMMER2_ROOT_VOLUME) {
 660                         bcopy(voldata, rootvoldata, sizeof(*rootvoldata));
 661                         KKASSERT(*rootvoldevvp == NULL);
 662                         *rootvoldevvp = e->devvp;
 663                 }
 664                 devvp->v_rdev->si_mountpoint = mp;
 665                 hprintf("\"%s\" zone=%d id=%d offset=0x%016jx size=0x%016jx\n",
 666                         path, zone, vol->id, (intmax_t)vol->offset,
 667                         (intmax_t)vol->size);
 668         }
 669 done:
 670         if (!error)
 671                 error = hammer2_verify_volumes(volumes, rootvoldata);
 672         kfree(voldata, M_HAMMER2);
 673
 674         return error;
 675 }
 676
 677 hammer2_volume_t*
 678 hammer2_get_volume(hammer2_dev_t *hmp, hammer2_off_t offset)
 679 {
 680         hammer2_volume_t *vol, *ret = NULL;
 681         int i;
 682
 683         offset &= ~HAMMER2_OFF_MASK_RADIX;
 684
 685         /* locking is unneeded until volume-add support */
 686         //hammer2_voldata_lock(hmp);
 687         /* do binary search if users really use this many supported volumes */
 688         for (i = 0; i < hmp->nvolumes; ++i) {
 689                 vol = &hmp->volumes[i];
 690                 if ((offset >= vol->offset) &&
 691                     (offset < vol->offset + vol->size)) {
 692                         ret = vol;
 693                         break;
 694                 }
 695         }
 696         //hammer2_voldata_unlock(hmp);
 697
 698         if (!ret)
 699                 panic("no volume for offset 0x%016jx", (intmax_t)offset);
 700
 701         KKASSERT(ret);
 702         KKASSERT(ret->dev);
 703         KKASSERT(ret->dev->devvp);
 704         KKASSERT(ret->dev->path);
 705
 706         return ret;
 707 }