sbin/hammer/ondisk.c

   1 /*
   2  * Copyright (c) 2007 The DragonFly Project.  All rights reserved.
   3  *
   4  * This code is derived from software contributed to The DragonFly Project
   5  * by Matthew Dillon <dillon@backplane.com>
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  *
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in
  15  *    the documentation and/or other materials provided with the
  16  *    distribution.
  17  * 3. Neither the name of The DragonFly Project nor the names of its
  18  *    contributors may be used to endorse or promote products derived
  19  *    from this software without specific, prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  22  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  23  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  24  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
  25  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
  26  * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
  27  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  28  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
  29  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  30  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
  31  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  32  * SUCH DAMAGE.
  33  */
  34
  35 #include <sys/diskslice.h>
  36 #include <sys/diskmbr.h>
  37
  38 #include "hammer_util.h"
  39
  40 static void check_volume(volume_info_t volume);
  41 static void get_buffer_readahead(buffer_info_t base);
  42 static __inline int readhammervol(volume_info_t volume);
  43 static __inline int readhammerbuf(buffer_info_t buffer);
  44 static __inline int writehammervol(volume_info_t volume);
  45 static __inline int writehammerbuf(buffer_info_t buffer);
  46
  47 uuid_t Hammer_FSType;
  48 uuid_t Hammer_FSId;
  49 int UseReadBehind = -4;
  50 int UseReadAhead = 4;
  51 int DebugOpt;
  52 uint32_t HammerVersion = -1;
  53
  54 TAILQ_HEAD(volume_list, volume_info);
  55 static struct volume_list VolList = TAILQ_HEAD_INITIALIZER(VolList);
  56 static int valid_hammer_volumes;
  57
  58 static __inline
  59 int
  60 buffer_hash(hammer_off_t zone2_offset)
  61 {
  62         int hi;
  63
  64         hi = (int)(zone2_offset / HAMMER_BUFSIZE) & HAMMER_BUFLISTMASK;
  65         return(hi);
  66 }
  67
  68 static buffer_info_t
  69 find_buffer(hammer_off_t zone2_offset)
  70 {
  71         volume_info_t volume;
  72         buffer_info_t buffer;
  73         int hi;
  74
  75         volume = get_volume(HAMMER_VOL_DECODE(zone2_offset));
  76         assert(volume);
  77
  78         hi = buffer_hash(zone2_offset);
  79         TAILQ_FOREACH(buffer, &volume->buffer_lists[hi], entry)
  80                 if (buffer->zone2_offset == zone2_offset)
  81                         return(buffer);
  82         return(NULL);
  83 }
  84
  85 static
  86 volume_info_t
  87 __alloc_volume(const char *volname, int oflags)
  88 {
  89         volume_info_t volume;
  90         int i;
  91
  92         volume = calloc(1, sizeof(*volume));
  93         volume->vol_no = -1;
  94         volume->rdonly = (oflags == O_RDONLY);
  95         volume->name = strdup(volname);
  96         volume->fd = open(volume->name, oflags);
  97         if (volume->fd < 0) {
  98                 err(1, "alloc_volume: Failed to open %s", volume->name);
  99                 /* not reached */
 100         }
 101         check_volume(volume);
 102
 103         volume->ondisk = calloc(1, HAMMER_BUFSIZE);
 104
 105         for (i = 0; i < HAMMER_BUFLISTS; ++i)
 106                 TAILQ_INIT(&volume->buffer_lists[i]);
 107
 108         return(volume);
 109 }
 110
 111 static void
 112 __add_volume(const volume_info_t volume)
 113 {
 114         volume_info_t scan;
 115         struct stat st1, st2;
 116
 117         if (fstat(volume->fd, &st1) != 0) {
 118                 errx(1, "add_volume: %s: Failed to stat", volume->name);
 119                 /* not reached */
 120         }
 121
 122         TAILQ_FOREACH(scan, &VolList, entry) {
 123                 if (scan->vol_no == volume->vol_no) {
 124                         errx(1, "add_volume: %s: Duplicate volume number %d "
 125                                 "against %s",
 126                                 volume->name, volume->vol_no, scan->name);
 127                         /* not reached */
 128                 }
 129                 if (fstat(scan->fd, &st2) != 0) {
 130                         errx(1, "add_volume: %s: Failed to stat %s",
 131                                 volume->name, scan->name);
 132                         /* not reached */
 133                 }
 134                 if ((st1.st_ino == st2.st_ino) && (st1.st_dev == st2.st_dev)) {
 135                         errx(1, "add_volume: %s: Specified more than once",
 136                                 volume->name);
 137                         /* not reached */
 138                 }
 139         }
 140
 141         TAILQ_INSERT_TAIL(&VolList, volume, entry);
 142 }
 143
 144 static void
 145 __verify_volume(const volume_info_t volume)
 146 {
 147         hammer_volume_ondisk_t ondisk = volume->ondisk;
 148
 149         if (ondisk->vol_signature != HAMMER_FSBUF_VOLUME) {
 150                 errx(1, "verify_volume: Invalid volume signature %016jx",
 151                         ondisk->vol_signature);
 152                 /* not reached */
 153         }
 154         if (ondisk->vol_rootvol != HAMMER_ROOT_VOLNO) {
 155                 errx(1, "verify_volume: Invalid root volume# %d",
 156                         ondisk->vol_rootvol);
 157                 /* not reached */
 158         }
 159         if (bcmp(&Hammer_FSType, &ondisk->vol_fstype, sizeof(Hammer_FSType))) {
 160                 errx(1, "verify_volume: %s: Header does not indicate "
 161                         "that this is a HAMMER volume", volume->name);
 162                 /* not reached */
 163         }
 164         if (bcmp(&Hammer_FSId, &ondisk->vol_fsid, sizeof(Hammer_FSId))) {
 165                 errx(1, "verify_volume: %s: FSId does not match other volumes!",
 166                         volume->name);
 167                 /* not reached */
 168         }
 169 }
 170
 171 /*
 172  * Initialize a volume structure and ondisk vol_no field.
 173  */
 174 volume_info_t
 175 init_volume(const char *filename, int oflags, int32_t vol_no)
 176 {
 177         volume_info_t volume;
 178
 179         volume = __alloc_volume(filename, oflags);
 180         volume->vol_no = volume->ondisk->vol_no = vol_no;
 181
 182         __add_volume(volume);
 183
 184         return(volume);
 185 }
 186
 187 /*
 188  * Initialize a volume structure and read ondisk volume header.
 189  */
 190 volume_info_t
 191 load_volume(const char *filename, int oflags, int verify)
 192 {
 193         volume_info_t volume;
 194         int n;
 195
 196         volume = __alloc_volume(filename, oflags);
 197
 198         n = readhammervol(volume);
 199         if (n == -1) {
 200                 err(1, "load_volume: %s: Read failed at offset 0",
 201                     volume->name);
 202                 /* not reached */
 203         }
 204         volume->vol_no = volume->ondisk->vol_no;
 205         HammerVersion = volume->ondisk->vol_version;
 206
 207         if (valid_hammer_volumes++ == 0)
 208                 Hammer_FSId = volume->ondisk->vol_fsid;
 209         if (verify)
 210                 __verify_volume(volume);
 211
 212         __add_volume(volume);
 213
 214         return(volume);
 215 }
 216
 217 /*
 218  * Check basic volume characteristics.
 219  */
 220 static void
 221 check_volume(volume_info_t volume)
 222 {
 223         struct partinfo pinfo;
 224         struct stat st;
 225
 226         /*
 227          * Allow the formatting of block devices or regular files
 228          */
 229         if (ioctl(volume->fd, DIOCGPART, &pinfo) < 0) {
 230                 if (fstat(volume->fd, &st) < 0) {
 231                         err(1, "Unable to stat %s", volume->name);
 232                         /* not reached */
 233                 }
 234                 if (S_ISREG(st.st_mode)) {
 235                         volume->size = st.st_size;
 236                         volume->type = "REGFILE";
 237                 } else {
 238                         errx(1, "Unsupported file type for %s", volume->name);
 239                         /* not reached */
 240                 }
 241         } else {
 242                 /*
 243                  * When formatting a block device as a HAMMER volume the
 244                  * sector size must be compatible.  HAMMER uses 16384 byte
 245                  * filesystem buffers.
 246                  */
 247                 if (pinfo.reserved_blocks) {
 248                         errx(1, "HAMMER cannot be placed in a partition "
 249                                 "which overlaps the disklabel or MBR");
 250                         /* not reached */
 251                 }
 252                 if (pinfo.media_blksize > HAMMER_BUFSIZE ||
 253                     HAMMER_BUFSIZE % pinfo.media_blksize) {
 254                         errx(1, "A media sector size of %d is not supported",
 255                              pinfo.media_blksize);
 256                         /* not reached */
 257                 }
 258
 259                 volume->size = pinfo.media_size;
 260                 volume->device_offset = pinfo.media_offset;
 261                 volume->type = "DEVICE";
 262         }
 263 }
 264
 265 int
 266 is_regfile(const volume_info_t volume)
 267 {
 268         return(strcmp(volume->type, "REGFILE") ? 0 : 1);
 269 }
 270
 271 void
 272 assert_volume_offset(const volume_info_t volume)
 273 {
 274         assert(hammer_is_zone_raw_buffer(volume->vol_free_off));
 275         assert(hammer_is_zone_raw_buffer(volume->vol_free_end));
 276         if (volume->vol_free_off >= volume->vol_free_end) {
 277                 errx(1, "Ran out of room, filesystem too small");
 278                 /* not reached */
 279         }
 280 }
 281
 282 volume_info_t
 283 get_volume(int32_t vol_no)
 284 {
 285         volume_info_t volume;
 286
 287         TAILQ_FOREACH(volume, &VolList, entry) {
 288                 if (volume->vol_no == vol_no)
 289                         break;
 290         }
 291
 292         return(volume);
 293 }
 294
 295 volume_info_t
 296 get_root_volume(void)
 297 {
 298         return(get_volume(HAMMER_ROOT_VOLNO));
 299 }
 300
 301 static hammer_off_t
 302 __blockmap_xlate_to_zone2(hammer_off_t buf_offset)
 303 {
 304         hammer_off_t zone2_offset;
 305         int error = 0;
 306
 307         if (hammer_is_zone_raw_buffer(buf_offset))
 308                 zone2_offset = buf_offset;
 309         else
 310                 zone2_offset = blockmap_lookup(buf_offset, &error);
 311
 312         if (error)
 313                 return(HAMMER_OFF_BAD);
 314         assert(hammer_is_zone_raw_buffer(zone2_offset));
 315
 316         return(zone2_offset);
 317 }
 318
 319 static buffer_info_t
 320 __alloc_buffer(hammer_off_t zone2_offset, int isnew)
 321 {
 322         volume_info_t volume;
 323         buffer_info_t buffer;
 324         int hi;
 325
 326         volume = get_volume(HAMMER_VOL_DECODE(zone2_offset));
 327         assert(volume != NULL);
 328
 329         buffer = calloc(1, sizeof(*buffer));
 330         buffer->zone2_offset = zone2_offset;
 331         buffer->raw_offset = hammer_xlate_to_phys(volume->ondisk, zone2_offset);
 332         buffer->volume = volume;
 333         buffer->ondisk = calloc(1, HAMMER_BUFSIZE);
 334
 335         if (isnew <= 0) {
 336                 if (readhammerbuf(buffer) == -1) {
 337                         err(1, "Failed to read %s:%016jx at %016jx",
 338                             volume->name,
 339                             (intmax_t)buffer->zone2_offset,
 340                             (intmax_t)buffer->raw_offset);
 341                         /* not reached */
 342                 }
 343         }
 344
 345         hi = buffer_hash(zone2_offset);
 346         TAILQ_INSERT_TAIL(&volume->buffer_lists[hi], buffer, entry);
 347         hammer_cache_add(&buffer->cache);
 348
 349         return(buffer);
 350 }
 351
 352 /*
 353  * Acquire the 16KB buffer for specified zone offset.
 354  */
 355 static buffer_info_t
 356 get_buffer(hammer_off_t buf_offset, int isnew)
 357 {
 358         buffer_info_t buffer;
 359         hammer_off_t zone2_offset;
 360         int dora = 0;
 361
 362         zone2_offset = __blockmap_xlate_to_zone2(buf_offset);
 363         if (zone2_offset == HAMMER_OFF_BAD)
 364                 return(NULL);
 365
 366         zone2_offset &= ~HAMMER_BUFMASK64;
 367         buffer = find_buffer(zone2_offset);
 368
 369         if (buffer == NULL) {
 370                 buffer = __alloc_buffer(zone2_offset, isnew);
 371                 dora = (isnew == 0);
 372         } else {
 373                 assert(isnew != -1);
 374                 hammer_cache_used(&buffer->cache);
 375         }
 376         assert(buffer->ondisk != NULL);
 377
 378         ++buffer->cache.refs;
 379         hammer_cache_flush();
 380
 381         if (isnew > 0) {
 382                 assert(buffer->cache.modified == 0);
 383                 bzero(buffer->ondisk, HAMMER_BUFSIZE);
 384                 buffer->cache.modified = 1;
 385         }
 386         if (dora)
 387                 get_buffer_readahead(buffer);
 388         return(buffer);
 389 }
 390
 391 static void
 392 get_buffer_readahead(const buffer_info_t base)
 393 {
 394         buffer_info_t buffer;
 395         volume_info_t volume;
 396         hammer_off_t zone2_offset;
 397         int64_t raw_offset;
 398         int ri = UseReadBehind;
 399         int re = UseReadAhead;
 400
 401         raw_offset = base->raw_offset + ri * HAMMER_BUFSIZE;
 402         volume = base->volume;
 403
 404         while (ri < re) {
 405                 if (raw_offset >= volume->ondisk->vol_buf_end)
 406                         break;
 407                 if (raw_offset < volume->ondisk->vol_buf_beg || ri == 0) {
 408                         ++ri;
 409                         raw_offset += HAMMER_BUFSIZE;
 410                         continue;
 411                 }
 412                 zone2_offset = HAMMER_ENCODE_RAW_BUFFER(volume->vol_no,
 413                         raw_offset - volume->ondisk->vol_buf_beg);
 414                 buffer = find_buffer(zone2_offset);
 415                 if (buffer == NULL) {
 416                         /* call with -1 to prevent another readahead */
 417                         buffer = get_buffer(zone2_offset, -1);
 418                         rel_buffer(buffer);
 419                 }
 420                 ++ri;
 421                 raw_offset += HAMMER_BUFSIZE;
 422         }
 423 }
 424
 425 void
 426 rel_buffer(buffer_info_t buffer)
 427 {
 428         volume_info_t volume;
 429         int hi;
 430
 431         if (buffer == NULL)
 432                 return;
 433         assert(buffer->cache.refs > 0);
 434         if (--buffer->cache.refs == 0) {
 435                 if (buffer->cache.delete) {
 436                         hi = buffer_hash(buffer->zone2_offset);
 437                         volume = buffer->volume;
 438                         if (buffer->cache.modified)
 439                                 flush_buffer(buffer);
 440                         TAILQ_REMOVE(&volume->buffer_lists[hi], buffer, entry);
 441                         hammer_cache_del(&buffer->cache);
 442                         free(buffer->ondisk);
 443                         free(buffer);
 444                 }
 445         }
 446 }
 447
 448 /*
 449  * Retrieve a pointer to a buffer data given a buffer offset.  The underlying
 450  * bufferp is freed if isnew or the offset is out of range of the cached data.
 451  * If bufferp is freed a referenced buffer is loaded into it.
 452  */
 453 void *
 454 get_buffer_data(hammer_off_t buf_offset, buffer_info_t *bufferp, int isnew)
 455 {
 456         hammer_off_t xor;
 457
 458         if (*bufferp != NULL) {
 459                 /* XXX xor is always non zero for indirect zones */
 460                 xor = HAMMER_OFF_LONG_ENCODE(buf_offset) ^
 461                       HAMMER_OFF_LONG_ENCODE((*bufferp)->zone2_offset);
 462                 if (isnew > 0 || (xor & ~HAMMER_BUFMASK64)) {
 463                         rel_buffer(*bufferp);
 464                         *bufferp = NULL;
 465                 }
 466         }
 467
 468         if (*bufferp == NULL) {
 469                 *bufferp = get_buffer(buf_offset, isnew);
 470                 if (*bufferp == NULL)
 471                         return(NULL);
 472         }
 473
 474         return(((char *)(*bufferp)->ondisk) +
 475                 ((int32_t)buf_offset & HAMMER_BUFMASK));
 476 }
 477
 478 /*
 479  * Allocate HAMMER elements - B-Tree nodes
 480  */
 481 hammer_node_ondisk_t
 482 alloc_btree_node(hammer_off_t *offp, buffer_info_t *data_bufferp)
 483 {
 484         hammer_node_ondisk_t node;
 485
 486         node = alloc_blockmap(HAMMER_ZONE_BTREE_INDEX, sizeof(*node),
 487                               offp, data_bufferp);
 488         bzero(node, sizeof(*node));
 489         return(node);
 490 }
 491
 492 /*
 493  * Allocate HAMMER elements - meta data (inode, direntry, PFS, etc)
 494  */
 495 void *
 496 alloc_meta_element(hammer_off_t *offp, int32_t data_len,
 497                    buffer_info_t *data_bufferp)
 498 {
 499         void *data;
 500
 501         data = alloc_blockmap(HAMMER_ZONE_META_INDEX, data_len,
 502                               offp, data_bufferp);
 503         bzero(data, data_len);
 504         return(data);
 505 }
 506
 507 /*
 508  * Format a new blockmap.  This is mostly a degenerate case because
 509  * all allocations are now actually done from the freemap.
 510  */
 511 void
 512 format_blockmap(volume_info_t root_vol, int zone, hammer_off_t offset)
 513 {
 514         hammer_blockmap_t blockmap;
 515         hammer_off_t zone_base;
 516
 517         /* Only root volume needs formatting */
 518         assert(root_vol->vol_no == HAMMER_ROOT_VOLNO);
 519
 520         assert(hammer_is_index_record(zone));
 521
 522         blockmap = &root_vol->ondisk->vol0_blockmap[zone];
 523         zone_base = HAMMER_ZONE_ENCODE(zone, offset);
 524
 525         bzero(blockmap, sizeof(*blockmap));
 526         blockmap->phys_offset = 0;
 527         blockmap->first_offset = zone_base;
 528         blockmap->next_offset = zone_base;
 529         blockmap->alloc_offset = HAMMER_ENCODE(zone, 255, -1);
 530         hammer_crc_set_blockmap(HammerVersion, blockmap);
 531 }
 532
 533 /*
 534  * Format a new freemap.  Set all layer1 entries to UNAVAIL.  The initialize
 535  * code will load each volume's freemap.
 536  */
 537 void
 538 format_freemap(volume_info_t root_vol)
 539 {
 540         buffer_info_t buffer = NULL;
 541         hammer_off_t layer1_offset;
 542         hammer_blockmap_t blockmap;
 543         hammer_blockmap_layer1_t layer1;
 544         int i, isnew;
 545
 546         /* Only root volume needs formatting */
 547         assert(root_vol->vol_no == HAMMER_ROOT_VOLNO);
 548
 549         layer1_offset = bootstrap_bigblock(root_vol);
 550         for (i = 0; i < HAMMER_BIGBLOCK_SIZE; i += sizeof(*layer1)) {
 551                 isnew = ((i % HAMMER_BUFSIZE) == 0);
 552                 layer1 = get_buffer_data(layer1_offset + i, &buffer, isnew);
 553                 bzero(layer1, sizeof(*layer1));
 554                 layer1->phys_offset = HAMMER_BLOCKMAP_UNAVAIL;
 555                 layer1->blocks_free = 0;
 556                 hammer_crc_set_layer1(HammerVersion, layer1);
 557         }
 558         assert(i == HAMMER_BIGBLOCK_SIZE);
 559         rel_buffer(buffer);
 560
 561         blockmap = &root_vol->ondisk->vol0_blockmap[HAMMER_ZONE_FREEMAP_INDEX];
 562         bzero(blockmap, sizeof(*blockmap));
 563         blockmap->phys_offset = layer1_offset;
 564         blockmap->first_offset = 0;
 565         blockmap->next_offset = HAMMER_ENCODE_RAW_BUFFER(0, 0);
 566         blockmap->alloc_offset = HAMMER_ENCODE_RAW_BUFFER(255, -1);
 567         hammer_crc_set_blockmap(HammerVersion, blockmap);
 568 }
 569
 570 /*
 571  * Load the volume's remaining free space into the freemap.
 572  *
 573  * Returns the number of big-blocks available.
 574  */
 575 int64_t
 576 initialize_freemap(volume_info_t volume)
 577 {
 578         volume_info_t root_vol;
 579         buffer_info_t buffer1 = NULL;
 580         buffer_info_t buffer2 = NULL;
 581         hammer_blockmap_layer1_t layer1;
 582         hammer_blockmap_layer2_t layer2;
 583         hammer_off_t layer1_offset;
 584         hammer_off_t layer2_offset;
 585         hammer_off_t phys_offset;
 586         hammer_off_t block_offset;
 587         hammer_off_t aligned_vol_free_end;
 588         hammer_blockmap_t freemap;
 589         int64_t count = 0;
 590         int64_t layer1_count = 0;
 591
 592         root_vol = get_root_volume();
 593
 594         assert_volume_offset(volume);
 595         aligned_vol_free_end = HAMMER_BLOCKMAP_LAYER2_DOALIGN(volume->vol_free_end);
 596
 597         printf("initialize freemap volume %d\n", volume->vol_no);
 598
 599         /*
 600          * Initialize the freemap.  First preallocate the big-blocks required
 601          * to implement layer2.   This preallocation is a bootstrap allocation
 602          * using blocks from the target volume.
 603          */
 604         freemap = &root_vol->ondisk->vol0_blockmap[HAMMER_ZONE_FREEMAP_INDEX];
 605
 606         for (phys_offset = HAMMER_ENCODE_RAW_BUFFER(volume->vol_no, 0);
 607              phys_offset < aligned_vol_free_end;
 608              phys_offset += HAMMER_BLOCKMAP_LAYER2) {
 609                 layer1_offset = freemap->phys_offset +
 610                                 HAMMER_BLOCKMAP_LAYER1_OFFSET(phys_offset);
 611                 layer1 = get_buffer_data(layer1_offset, &buffer1, 0);
 612                 if (layer1->phys_offset == HAMMER_BLOCKMAP_UNAVAIL) {
 613                         layer1->phys_offset = bootstrap_bigblock(volume);
 614                         layer1->blocks_free = 0;
 615                         buffer1->cache.modified = 1;
 616                         hammer_crc_set_layer1(HammerVersion, layer1);
 617                 }
 618         }
 619
 620         /*
 621          * Now fill everything in.
 622          */
 623         for (phys_offset = HAMMER_ENCODE_RAW_BUFFER(volume->vol_no, 0);
 624              phys_offset < aligned_vol_free_end;
 625              phys_offset += HAMMER_BLOCKMAP_LAYER2) {
 626                 layer1_count = 0;
 627                 layer1_offset = freemap->phys_offset +
 628                                 HAMMER_BLOCKMAP_LAYER1_OFFSET(phys_offset);
 629                 layer1 = get_buffer_data(layer1_offset, &buffer1, 0);
 630                 assert(layer1->phys_offset != HAMMER_BLOCKMAP_UNAVAIL);
 631
 632                 for (block_offset = 0;
 633                      block_offset < HAMMER_BLOCKMAP_LAYER2;
 634                      block_offset += HAMMER_BIGBLOCK_SIZE) {
 635                         layer2_offset = layer1->phys_offset +
 636                                         HAMMER_BLOCKMAP_LAYER2_OFFSET(block_offset);
 637                         layer2 = get_buffer_data(layer2_offset, &buffer2, 0);
 638                         bzero(layer2, sizeof(*layer2));
 639
 640                         if (phys_offset + block_offset < volume->vol_free_off) {
 641                                 /*
 642                                  * Big-blocks already allocated as part
 643                                  * of the freemap bootstrap.
 644                                  */
 645                                 layer2->zone = HAMMER_ZONE_FREEMAP_INDEX;
 646                                 layer2->append_off = HAMMER_BIGBLOCK_SIZE;
 647                                 layer2->bytes_free = 0;
 648                         } else if (phys_offset + block_offset < volume->vol_free_end) {
 649                                 layer2->zone = 0;
 650                                 layer2->append_off = 0;
 651                                 layer2->bytes_free = HAMMER_BIGBLOCK_SIZE;
 652                                 ++count;
 653                                 ++layer1_count;
 654                         } else {
 655                                 layer2->zone = HAMMER_ZONE_UNAVAIL_INDEX;
 656                                 layer2->append_off = HAMMER_BIGBLOCK_SIZE;
 657                                 layer2->bytes_free = 0;
 658                         }
 659                         hammer_crc_set_layer2(HammerVersion, layer2);
 660                         buffer2->cache.modified = 1;
 661                 }
 662
 663                 layer1->blocks_free += layer1_count;
 664                 hammer_crc_set_layer1(HammerVersion, layer1);
 665                 buffer1->cache.modified = 1;
 666         }
 667
 668         rel_buffer(buffer1);
 669         rel_buffer(buffer2);
 670         return(count);
 671 }
 672
 673 /*
 674  * Returns the number of big-blocks available for filesystem data and undos
 675  * without formatting.
 676  */
 677 int64_t
 678 count_freemap(const volume_info_t volume)
 679 {
 680         hammer_off_t phys_offset;
 681         hammer_off_t vol_free_off;
 682         hammer_off_t aligned_vol_free_end;
 683         int64_t count = 0;
 684
 685         vol_free_off = HAMMER_ENCODE_RAW_BUFFER(volume->vol_no, 0);
 686
 687         assert_volume_offset(volume);
 688         aligned_vol_free_end = HAMMER_BLOCKMAP_LAYER2_DOALIGN(volume->vol_free_end);
 689
 690         if (volume->vol_no == HAMMER_ROOT_VOLNO)
 691                 vol_free_off += HAMMER_BIGBLOCK_SIZE;
 692
 693         for (phys_offset = HAMMER_ENCODE_RAW_BUFFER(volume->vol_no, 0);
 694              phys_offset < aligned_vol_free_end;
 695              phys_offset += HAMMER_BLOCKMAP_LAYER2) {
 696                 vol_free_off += HAMMER_BIGBLOCK_SIZE;
 697         }
 698
 699         for (phys_offset = HAMMER_ENCODE_RAW_BUFFER(volume->vol_no, 0);
 700              phys_offset < aligned_vol_free_end;
 701              phys_offset += HAMMER_BIGBLOCK_SIZE) {
 702                 if (phys_offset < vol_free_off)
 703                         ;
 704                 else if (phys_offset < volume->vol_free_end)
 705                         ++count;
 706         }
 707
 708         return(count);
 709 }
 710
 711 /*
 712  * Format the undomap for the root volume.
 713  */
 714 void
 715 format_undomap(volume_info_t root_vol, int64_t *undo_buffer_size)
 716 {
 717         hammer_off_t undo_limit;
 718         hammer_blockmap_t blockmap;
 719         hammer_volume_ondisk_t ondisk;
 720         buffer_info_t buffer = NULL;
 721         hammer_off_t scan;
 722         int n;
 723         int limit_index;
 724         uint32_t seqno;
 725
 726         /* Only root volume needs formatting */
 727         assert(root_vol->vol_no == HAMMER_ROOT_VOLNO);
 728         ondisk = root_vol->ondisk;
 729
 730         /*
 731          * Size the undo buffer in multiples of HAMMER_BIGBLOCK_SIZE,
 732          * up to HAMMER_MAX_UNDO_BIGBLOCKS big-blocks.
 733          * Size to approximately 0.1% of the disk.
 734          *
 735          * The minimum UNDO fifo size is 512MB, or approximately 1% of
 736          * the recommended 50G disk.
 737          *
 738          * Changing this minimum is rather dangerous as complex filesystem
 739          * operations can cause the UNDO FIFO to fill up otherwise.
 740          */
 741         undo_limit = *undo_buffer_size;
 742         if (undo_limit == 0) {
 743                 undo_limit = HAMMER_VOL_BUF_SIZE(ondisk) / 1000;
 744                 if (undo_limit < HAMMER_BIGBLOCK_SIZE * HAMMER_MIN_UNDO_BIGBLOCKS)
 745                         undo_limit = HAMMER_BIGBLOCK_SIZE * HAMMER_MIN_UNDO_BIGBLOCKS;
 746         }
 747         undo_limit = HAMMER_BIGBLOCK_DOALIGN(undo_limit);
 748         if (undo_limit < HAMMER_BIGBLOCK_SIZE)
 749                 undo_limit = HAMMER_BIGBLOCK_SIZE;
 750         if (undo_limit > HAMMER_BIGBLOCK_SIZE * HAMMER_MAX_UNDO_BIGBLOCKS)
 751                 undo_limit = HAMMER_BIGBLOCK_SIZE * HAMMER_MAX_UNDO_BIGBLOCKS;
 752         *undo_buffer_size = undo_limit;
 753
 754         blockmap = &ondisk->vol0_blockmap[HAMMER_ZONE_UNDO_INDEX];
 755         bzero(blockmap, sizeof(*blockmap));
 756         blockmap->phys_offset = HAMMER_BLOCKMAP_UNAVAIL;
 757         blockmap->first_offset = HAMMER_ENCODE_UNDO(0);
 758         blockmap->next_offset = blockmap->first_offset;
 759         blockmap->alloc_offset = HAMMER_ENCODE_UNDO(undo_limit);
 760         hammer_crc_set_blockmap(HammerVersion, blockmap);
 761
 762         limit_index = undo_limit / HAMMER_BIGBLOCK_SIZE;
 763         assert(limit_index <= HAMMER_MAX_UNDO_BIGBLOCKS);
 764
 765         for (n = 0; n < limit_index; ++n)
 766                 ondisk->vol0_undo_array[n] = alloc_undo_bigblock(root_vol);
 767         while (n < HAMMER_MAX_UNDO_BIGBLOCKS)
 768                 ondisk->vol0_undo_array[n++] = HAMMER_BLOCKMAP_UNAVAIL;
 769
 770         /*
 771          * Pre-initialize the UNDO blocks (HAMMER version 4+)
 772          */
 773         printf("initializing the undo map (%jd MB)\n",
 774                 (intmax_t)HAMMER_OFF_LONG_ENCODE(blockmap->alloc_offset) /
 775                 (1024 * 1024));
 776
 777         scan = blockmap->first_offset;
 778         seqno = 0;
 779
 780         while (scan < blockmap->alloc_offset) {
 781                 hammer_fifo_head_t head;
 782                 hammer_fifo_tail_t tail;
 783                 int isnew;
 784                 int bytes = HAMMER_UNDO_ALIGN;
 785
 786                 isnew = ((scan & HAMMER_BUFMASK64) == 0);
 787                 head = get_buffer_data(scan, &buffer, isnew);
 788                 buffer->cache.modified = 1;
 789                 tail = (void *)((char *)head + bytes - sizeof(*tail));
 790
 791                 bzero(head, bytes);
 792                 head->hdr_signature = HAMMER_HEAD_SIGNATURE;
 793                 head->hdr_type = HAMMER_HEAD_TYPE_DUMMY;
 794                 head->hdr_size = bytes;
 795                 head->hdr_seq = seqno++;
 796
 797                 tail->tail_signature = HAMMER_TAIL_SIGNATURE;
 798                 tail->tail_type = HAMMER_HEAD_TYPE_DUMMY;
 799                 tail->tail_size = bytes;
 800
 801                 hammer_crc_set_fifo_head(HammerVersion, head, bytes);
 802
 803                 scan += bytes;
 804         }
 805         rel_buffer(buffer);
 806 }
 807
 808 const char *zone_labels[] = {
 809         "",             /* 0 */
 810         "raw_volume",   /* 1 */
 811         "raw_buffer",   /* 2 */
 812         "undo",         /* 3 */
 813         "freemap",      /* 4 */
 814         "",             /* 5 */
 815         "",             /* 6 */
 816         "",             /* 7 */
 817         "btree",        /* 8 */
 818         "meta",         /* 9 */
 819         "large_data",   /* 10 */
 820         "small_data",   /* 11 */
 821         "",             /* 12 */
 822         "",             /* 13 */
 823         "",             /* 14 */
 824         "unavail",      /* 15 */
 825 };
 826
 827 void
 828 print_blockmap(const volume_info_t volume)
 829 {
 830         hammer_blockmap_t blockmap;
 831         hammer_volume_ondisk_t ondisk;
 832         int64_t size, used;
 833         int i;
 834 #define INDENT ""
 835
 836         ondisk = volume->ondisk;
 837         printf(INDENT"vol_label\t%s\n", ondisk->vol_label);
 838         printf(INDENT"vol_count\t%d\n", ondisk->vol_count);
 839         printf(INDENT"vol_bot_beg\t%s\n", sizetostr(ondisk->vol_bot_beg));
 840         printf(INDENT"vol_mem_beg\t%s\n", sizetostr(ondisk->vol_mem_beg));
 841         printf(INDENT"vol_buf_beg\t%s\n", sizetostr(ondisk->vol_buf_beg));
 842         printf(INDENT"vol_buf_end\t%s\n", sizetostr(ondisk->vol_buf_end));
 843         printf(INDENT"vol0_next_tid\t%016jx\n",
 844                (uintmax_t)ondisk->vol0_next_tid);
 845
 846         blockmap = &ondisk->vol0_blockmap[HAMMER_ZONE_UNDO_INDEX];
 847         size = HAMMER_OFF_LONG_ENCODE(blockmap->alloc_offset);
 848         if (blockmap->first_offset <= blockmap->next_offset)
 849                 used = blockmap->next_offset - blockmap->first_offset;
 850         else
 851                 used = blockmap->alloc_offset - blockmap->first_offset +
 852                         HAMMER_OFF_LONG_ENCODE(blockmap->next_offset);
 853         printf(INDENT"undo_size\t%s\n", sizetostr(size));
 854         printf(INDENT"undo_used\t%s\n", sizetostr(used));
 855
 856         printf(INDENT"zone #             "
 857                "phys             first            next             alloc\n");
 858         for (i = 0; i < HAMMER_MAX_ZONES; i++) {
 859                 blockmap = &ondisk->vol0_blockmap[i];
 860                 printf(INDENT"zone %-2d %-10s %016jx %016jx %016jx %016jx\n",
 861                         i, zone_labels[i],
 862                         (uintmax_t)blockmap->phys_offset,
 863                         (uintmax_t)blockmap->first_offset,
 864                         (uintmax_t)blockmap->next_offset,
 865                         (uintmax_t)blockmap->alloc_offset);
 866         }
 867 }
 868
 869 /*
 870  * Flush various tracking structures to disk
 871  */
 872 void
 873 flush_all_volumes(void)
 874 {
 875         volume_info_t volume;
 876
 877         TAILQ_FOREACH(volume, &VolList, entry)
 878                 flush_volume(volume);
 879 }
 880
 881 void
 882 flush_volume(volume_info_t volume)
 883 {
 884         buffer_info_t buffer;
 885         int i;
 886
 887         for (i = 0; i < HAMMER_BUFLISTS; ++i) {
 888                 TAILQ_FOREACH(buffer, &volume->buffer_lists[i], entry)
 889                         flush_buffer(buffer);
 890         }
 891         if (writehammervol(volume) == -1) {
 892                 err(1, "Write volume %d (%s)", volume->vol_no, volume->name);
 893                 /* not reached */
 894         }
 895 }
 896
 897 void
 898 flush_buffer(buffer_info_t buffer)
 899 {
 900         volume_info_t volume;
 901
 902         volume = buffer->volume;
 903         if (writehammerbuf(buffer) == -1) {
 904                 err(1, "Write volume %d (%s)", volume->vol_no, volume->name);
 905                 /* not reached */
 906         }
 907         buffer->cache.modified = 0;
 908 }
 909
 910 /*
 911  * Core I/O operations
 912  */
 913 static int
 914 __read(volume_info_t volume, void *data, int64_t offset, int size)
 915 {
 916         ssize_t n;
 917
 918         n = pread(volume->fd, data, size, offset);
 919         if (n != size)
 920                 return(-1);
 921         return(0);
 922 }
 923
 924 static __inline int
 925 readhammervol(volume_info_t volume)
 926 {
 927         return(__read(volume, volume->ondisk, 0, HAMMER_BUFSIZE));
 928 }
 929
 930 static __inline int
 931 readhammerbuf(buffer_info_t buffer)
 932 {
 933         return(__read(buffer->volume, buffer->ondisk, buffer->raw_offset,
 934                 HAMMER_BUFSIZE));
 935 }
 936
 937 static int
 938 __write(volume_info_t volume, const void *data, int64_t offset, int size)
 939 {
 940         ssize_t n;
 941
 942         if (volume->rdonly)
 943                 return(0);
 944
 945         n = pwrite(volume->fd, data, size, offset);
 946         if (n != size)
 947                 return(-1);
 948         return(0);
 949 }
 950
 951 static __inline int
 952 writehammervol(volume_info_t volume)
 953 {
 954         return(__write(volume, volume->ondisk, 0, HAMMER_BUFSIZE));
 955 }
 956
 957 static __inline int
 958 writehammerbuf(buffer_info_t buffer)
 959 {
 960         return(__write(buffer->volume, buffer->ondisk, buffer->raw_offset,
 961                 HAMMER_BUFSIZE));
 962 }
 963
 964 int64_t init_boot_area_size(int64_t value, off_t avg_vol_size)
 965 {
 966         if (value == 0) {
 967                 value = HAMMER_BOOT_NOMBYTES;
 968                 while (value > avg_vol_size / HAMMER_MAX_VOLUMES)
 969                         value >>= 1;
 970         }
 971
 972         if (value < HAMMER_BOOT_MINBYTES)
 973                 value = HAMMER_BOOT_MINBYTES;
 974         else if (value > HAMMER_BOOT_MAXBYTES)
 975                 value = HAMMER_BOOT_MAXBYTES;
 976
 977         return(value);
 978 }
 979
 980 int64_t init_memory_log_size(int64_t value, off_t avg_vol_size)
 981 {
 982         if (value == 0) {
 983                 value = HAMMER_MEM_NOMBYTES;
 984                 while (value > avg_vol_size / HAMMER_MAX_VOLUMES)
 985                         value >>= 1;
 986         }
 987
 988         if (value < HAMMER_MEM_MINBYTES)
 989                 value = HAMMER_MEM_MINBYTES;
 990         else if (value > HAMMER_MEM_MAXBYTES)
 991                 value = HAMMER_MEM_MAXBYTES;
 992
 993         return(value);
 994 }