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/types.h>
  36 #include <sys/stat.h>
  37 #include <assert.h>
  38 #include <stdio.h>
  39 #include <stdlib.h>
  40 #include <stdarg.h>
  41 #include <string.h>
  42 #include <unistd.h>
  43 #include <stddef.h>
  44 #include <err.h>
  45 #include <fcntl.h>
  46 #include "hammer_util.h"
  47
  48 static void *alloc_blockmap(int zone, int bytes, hammer_off_t *result_offp,
  49                         struct buffer_info **bufferp);
  50 static hammer_off_t alloc_bigblock(struct volume_info *volume, int zone);
  51 static void get_buffer_readahead(struct buffer_info *base);
  52 static __inline void *get_ondisk(hammer_off_t buf_offset,
  53                         struct buffer_info **bufferp, int isnew);
  54 #if 0
  55 static void init_fifo_head(hammer_fifo_head_t head, u_int16_t hdr_type);
  56 static void readhammerbuf(struct volume_info *vol, void *data,
  57                         int64_t offset);
  58 #endif
  59 static void writehammerbuf(struct volume_info *vol, const void *data,
  60                         int64_t offset);
  61
  62 int DebugOpt;
  63
  64 uuid_t Hammer_FSType;
  65 uuid_t Hammer_FSId;
  66 int64_t BootAreaSize;
  67 int64_t MemAreaSize;
  68 int64_t UndoBufferSize;
  69 int     UsingSuperClusters;
  70 int     NumVolumes;
  71 int     RootVolNo = -1;
  72 int     UseReadBehind = -4;
  73 int     UseReadAhead = 4;
  74 int     AssertOnFailure = 1;
  75 struct volume_list VolList = TAILQ_HEAD_INITIALIZER(VolList);
  76
  77 static __inline
  78 int
  79 buffer_hash(hammer_off_t buf_offset)
  80 {
  81         int hi;
  82
  83         hi = (int)(buf_offset / HAMMER_BUFSIZE) & HAMMER_BUFLISTMASK;
  84         return(hi);
  85 }
  86
  87 static struct buffer_info*
  88 find_buffer(struct volume_info *volume, hammer_off_t buf_offset)
  89 {
  90         int hi;
  91         struct buffer_info *buf;
  92
  93         hi = buffer_hash(buf_offset);
  94         TAILQ_FOREACH(buf, &volume->buffer_lists[hi], entry)
  95                 if (buf->buf_offset == buf_offset)
  96                         return(buf);
  97         return(NULL);
  98 }
  99
 100 /*
 101  * Lookup the requested information structure and related on-disk buffer.
 102  * Missing structures are created.
 103  */
 104 struct volume_info *
 105 setup_volume(int32_t vol_no, const char *filename, int isnew, int oflags)
 106 {
 107         struct volume_info *vol;
 108         struct volume_info *scan;
 109         struct hammer_volume_ondisk *ondisk;
 110         int i, n;
 111         struct stat st1, st2;
 112
 113         /*
 114          * Allocate the volume structure
 115          */
 116         vol = malloc(sizeof(*vol));
 117         bzero(vol, sizeof(*vol));
 118         for (i = 0; i < HAMMER_BUFLISTS; ++i)
 119                 TAILQ_INIT(&vol->buffer_lists[i]);
 120         vol->name = strdup(filename);
 121         vol->fd = open(vol->name, oflags);
 122         if (vol->fd < 0) {
 123                 err(1, "setup_volume: %s: Open failed", vol->name);
 124                 free(vol->name);
 125                 free(vol);
 126         }
 127
 128         /*
 129          * Read or initialize the volume header
 130          */
 131         vol->ondisk = ondisk = malloc(HAMMER_BUFSIZE);
 132         if (isnew > 0) {
 133                 bzero(ondisk, HAMMER_BUFSIZE);
 134         } else {
 135                 n = pread(vol->fd, ondisk, HAMMER_BUFSIZE, 0);
 136                 if (n != HAMMER_BUFSIZE) {
 137                         err(1, "setup_volume: %s: Read failed at offset 0",
 138                             vol->name);
 139                 }
 140                 vol_no = ondisk->vol_no;
 141                 if (RootVolNo < 0) {
 142                         RootVolNo = ondisk->vol_rootvol;
 143                 } else if (RootVolNo != (int)ondisk->vol_rootvol) {
 144                         errx(1, "setup_volume: %s: root volume disagreement: "
 145                                 "%d vs %d",
 146                                 vol->name, RootVolNo, ondisk->vol_rootvol);
 147                 }
 148
 149                 if (bcmp(&Hammer_FSType, &ondisk->vol_fstype, sizeof(Hammer_FSType)) != 0) {
 150                         errx(1, "setup_volume: %s: Header does not indicate "
 151                                 "that this is a hammer volume", vol->name);
 152                 }
 153                 if (TAILQ_EMPTY(&VolList)) {
 154                         Hammer_FSId = vol->ondisk->vol_fsid;
 155                 } else if (bcmp(&Hammer_FSId, &ondisk->vol_fsid, sizeof(Hammer_FSId)) != 0) {
 156                         errx(1, "setup_volume: %s: FSId does match other "
 157                                 "volumes!", vol->name);
 158                 }
 159         }
 160         vol->vol_no = vol_no;
 161
 162         if (isnew > 0) {
 163                 /*init_fifo_head(&ondisk->head, HAMMER_HEAD_TYPE_VOL);*/
 164                 vol->cache.modified = 1;
 165         }
 166
 167         if (fstat(vol->fd, &st1) != 0){
 168                 errx(1, "setup_volume: %s: Failed to stat", vol->name);
 169         }
 170
 171         /*
 172          * Link the volume structure in
 173          */
 174         TAILQ_FOREACH(scan, &VolList, entry) {
 175                 if (scan->vol_no == vol_no) {
 176                         errx(1, "setup_volume: %s: Duplicate volume number %d "
 177                                 "against %s", vol->name, vol_no, scan->name);
 178                 }
 179                 if (fstat(scan->fd, &st2) != 0){
 180                         errx(1, "setup_volume: %s: Failed to stat %s",
 181                                 vol->name, scan->name);
 182                 }
 183                 if ((st1.st_ino == st2.st_ino) && (st1.st_dev == st2.st_dev)) {
 184                         errx(1, "setup_volume: %s: Specified more than once",
 185                                 vol->name);
 186                 }
 187         }
 188         TAILQ_INSERT_TAIL(&VolList, vol, entry);
 189         return(vol);
 190 }
 191
 192 struct volume_info *
 193 get_volume(int32_t vol_no)
 194 {
 195         struct volume_info *vol;
 196
 197         TAILQ_FOREACH(vol, &VolList, entry) {
 198                 if (vol->vol_no == vol_no)
 199                         break;
 200         }
 201         if (vol == NULL) {
 202                 if (AssertOnFailure)
 203                         errx(1, "get_volume: Volume %d does not exist!",
 204                                 vol_no);
 205                 return(NULL);
 206         }
 207         ++vol->cache.refs;
 208         /* not added to or removed from hammer cache */
 209         return(vol);
 210 }
 211
 212 void
 213 rel_volume(struct volume_info *volume)
 214 {
 215         if (volume == NULL)
 216                 return;
 217         /* not added to or removed from hammer cache */
 218         --volume->cache.refs;
 219 }
 220
 221 /*
 222  * Acquire the specified buffer.  isnew is -1 only when called
 223  * via get_buffer_readahead() to prevent another readahead.
 224  */
 225 struct buffer_info *
 226 get_buffer(hammer_off_t buf_offset, int isnew)
 227 {
 228         void *ondisk;
 229         struct buffer_info *buf;
 230         struct volume_info *volume;
 231         hammer_off_t orig_offset = buf_offset;
 232         int vol_no;
 233         int zone;
 234         int hi, n;
 235         int dora = 0;
 236
 237         zone = HAMMER_ZONE_DECODE(buf_offset);
 238         if (zone > HAMMER_ZONE_RAW_BUFFER_INDEX) {
 239                 buf_offset = blockmap_lookup(buf_offset, NULL, NULL, NULL);
 240         }
 241         if (buf_offset == HAMMER_OFF_BAD)
 242                 return(NULL);
 243
 244         if (AssertOnFailure) {
 245                 assert((buf_offset & HAMMER_OFF_ZONE_MASK) ==
 246                        HAMMER_ZONE_RAW_BUFFER);
 247         }
 248         vol_no = HAMMER_VOL_DECODE(buf_offset);
 249         volume = get_volume(vol_no);
 250         if (volume == NULL)
 251                 return(NULL);
 252
 253         buf_offset &= ~HAMMER_BUFMASK64;
 254         buf = find_buffer(volume, buf_offset);
 255
 256         if (buf == NULL) {
 257                 buf = malloc(sizeof(*buf));
 258                 bzero(buf, sizeof(*buf));
 259                 if (DebugOpt) {
 260                         fprintf(stderr, "get_buffer: %016llx %016llx at %p\n",
 261                                 (long long)orig_offset, (long long)buf_offset,
 262                                 buf);
 263                 }
 264                 buf->buf_offset = buf_offset;
 265                 buf->raw_offset = volume->ondisk->vol_buf_beg +
 266                                   (buf_offset & HAMMER_OFF_SHORT_MASK);
 267                 buf->volume = volume;
 268                 hi = buffer_hash(buf_offset);
 269                 TAILQ_INSERT_TAIL(&volume->buffer_lists[hi], buf, entry);
 270                 ++volume->cache.refs;
 271                 buf->cache.u.buffer = buf;
 272                 hammer_cache_add(&buf->cache, ISBUFFER);
 273                 dora = (isnew == 0);
 274         } else {
 275                 if (DebugOpt) {
 276                         fprintf(stderr, "get_buffer: %016llx %016llx at %p *\n",
 277                                 (long long)orig_offset, (long long)buf_offset,
 278                                 buf);
 279                 }
 280                 hammer_cache_used(&buf->cache);
 281                 ++buf->use_count;
 282         }
 283         ++buf->cache.refs;
 284         hammer_cache_flush();
 285         if ((ondisk = buf->ondisk) == NULL) {
 286                 buf->ondisk = ondisk = malloc(HAMMER_BUFSIZE);
 287                 if (isnew <= 0) {
 288                         n = pread(volume->fd, ondisk, HAMMER_BUFSIZE,
 289                                   buf->raw_offset);
 290                         if (n != HAMMER_BUFSIZE) {
 291                                 if (AssertOnFailure)
 292                                         err(1, "get_buffer: %s:%016llx "
 293                                             "Read failed at offset %016llx",
 294                                             volume->name,
 295                                             (long long)buf->buf_offset,
 296                                             (long long)buf->raw_offset);
 297                                 bzero(ondisk, HAMMER_BUFSIZE);
 298                         }
 299                 }
 300         }
 301         if (isnew > 0) {
 302                 bzero(ondisk, HAMMER_BUFSIZE);
 303                 buf->cache.modified = 1;
 304         }
 305         if (dora)
 306                 get_buffer_readahead(buf);
 307         return(buf);
 308 }
 309
 310 static void
 311 get_buffer_readahead(struct buffer_info *base)
 312 {
 313         struct buffer_info *buf;
 314         struct volume_info *vol;
 315         hammer_off_t buf_offset;
 316         int64_t raw_offset;
 317         int ri = UseReadBehind;
 318         int re = UseReadAhead;
 319
 320         raw_offset = base->raw_offset + ri * HAMMER_BUFSIZE;
 321         vol = base->volume;
 322
 323         while (ri < re) {
 324                 if (raw_offset >= vol->ondisk->vol_buf_end)
 325                         break;
 326                 if (raw_offset < vol->ondisk->vol_buf_beg || ri == 0) {
 327                         ++ri;
 328                         raw_offset += HAMMER_BUFSIZE;
 329                         continue;
 330                 }
 331                 buf_offset = HAMMER_ENCODE_RAW_BUFFER(vol->vol_no,
 332                         raw_offset - vol->ondisk->vol_buf_beg);
 333                 buf = find_buffer(vol, buf_offset);
 334                 if (buf == NULL) {
 335                         buf = get_buffer(buf_offset, -1);
 336                         rel_buffer(buf);
 337                 }
 338                 ++ri;
 339                 raw_offset += HAMMER_BUFSIZE;
 340         }
 341 }
 342
 343 void
 344 rel_buffer(struct buffer_info *buffer)
 345 {
 346         struct volume_info *volume;
 347         int hi;
 348
 349         if (buffer == NULL)
 350                 return;
 351         assert(buffer->cache.refs > 0);
 352         if (--buffer->cache.refs == 0) {
 353                 if (buffer->cache.delete) {
 354                         hi = buffer_hash(buffer->buf_offset);
 355                         volume = buffer->volume;
 356                         if (buffer->cache.modified)
 357                                 flush_buffer(buffer);
 358                         TAILQ_REMOVE(&volume->buffer_lists[hi], buffer, entry);
 359                         hammer_cache_del(&buffer->cache);
 360                         free(buffer->ondisk);
 361                         free(buffer);
 362                         rel_volume(volume);
 363                 }
 364         }
 365 }
 366
 367 /*
 368  * Retrieve a pointer to a buffer data given a buffer offset.  The underlying
 369  * bufferp is freed if isnew or the offset is out of range of the cached data.
 370  * If bufferp is freed a referenced buffer is loaded into it.
 371  */
 372 void *
 373 get_buffer_data(hammer_off_t buf_offset, struct buffer_info **bufferp,
 374                 int isnew)
 375 {
 376         if (*bufferp != NULL) {
 377                 if (isnew > 0 ||
 378                     (((*bufferp)->buf_offset ^ buf_offset) & ~HAMMER_BUFMASK64)) {
 379                         rel_buffer(*bufferp);
 380                         *bufferp = NULL;
 381                 }
 382         }
 383         return(get_ondisk(buf_offset, bufferp, isnew));
 384 }
 385
 386 /*
 387  * Retrieve a pointer to a B-Tree node given a cluster offset.  The underlying
 388  * bufferp is freed if non-NULL and a referenced buffer is loaded into it.
 389  */
 390 hammer_node_ondisk_t
 391 get_node(hammer_off_t node_offset, struct buffer_info **bufferp)
 392 {
 393         if (*bufferp != NULL) {
 394                 rel_buffer(*bufferp);
 395                 *bufferp = NULL;
 396         }
 397         return(get_ondisk(node_offset, bufferp, 0));
 398 }
 399
 400 /*
 401  * Return a pointer to a buffer data given a buffer offset.
 402  * If *bufferp is NULL acquire the buffer otherwise use that buffer.
 403  */
 404 static __inline
 405 void *
 406 get_ondisk(hammer_off_t buf_offset, struct buffer_info **bufferp,
 407         int isnew)
 408 {
 409         struct buffer_info *buffer;
 410
 411         buffer = *bufferp;
 412         if (buffer == NULL) {
 413                 buffer = *bufferp = get_buffer(buf_offset, isnew);
 414                 if (buffer == NULL)
 415                         return(NULL);
 416         }
 417
 418         return((char *)buffer->ondisk +
 419                 ((int32_t)buf_offset & HAMMER_BUFMASK));
 420 }
 421
 422 /*
 423  * Allocate HAMMER elements - btree nodes, meta data, data storage
 424  */
 425 void *
 426 alloc_btree_element(hammer_off_t *offp,
 427                     struct buffer_info **data_bufferp)
 428 {
 429         hammer_node_ondisk_t node;
 430
 431         node = alloc_blockmap(HAMMER_ZONE_BTREE_INDEX, sizeof(*node),
 432                               offp, data_bufferp);
 433         bzero(node, sizeof(*node));
 434         return (node);
 435 }
 436
 437 void *
 438 alloc_meta_element(hammer_off_t *offp, int32_t data_len,
 439                    struct buffer_info **data_bufferp)
 440 {
 441         void *data;
 442
 443         data = alloc_blockmap(HAMMER_ZONE_META_INDEX, data_len,
 444                               offp, data_bufferp);
 445         bzero(data, data_len);
 446         return (data);
 447 }
 448
 449 void *
 450 alloc_data_element(hammer_off_t *offp, int32_t data_len,
 451                    struct buffer_info **data_bufferp)
 452 {
 453         void *data;
 454
 455         if (data_len >= HAMMER_BUFSIZE) {
 456                 assert(data_len <= HAMMER_BUFSIZE); /* just one buffer */
 457                 data = alloc_blockmap(HAMMER_ZONE_LARGE_DATA_INDEX, data_len,
 458                                       offp, data_bufferp);
 459                 bzero(data, data_len);
 460         } else if (data_len) {
 461                 data = alloc_blockmap(HAMMER_ZONE_SMALL_DATA_INDEX, data_len,
 462                                       offp, data_bufferp);
 463                 bzero(data, data_len);
 464         } else {
 465                 data = NULL;
 466         }
 467         return (data);
 468 }
 469
 470 /*
 471  * Format a new freemap.  Set all layer1 entries to UNAVAIL.  The initialize
 472  * code will load each volume's freemap.
 473  */
 474 void
 475 format_freemap(struct volume_info *root_vol, hammer_blockmap_t blockmap)
 476 {
 477         struct buffer_info *buffer = NULL;
 478         hammer_off_t layer1_offset;
 479         struct hammer_blockmap_layer1 *layer1;
 480         int i, isnew;
 481
 482         layer1_offset = alloc_bigblock(root_vol, HAMMER_ZONE_FREEMAP_INDEX);
 483         for (i = 0; i < (int)HAMMER_BLOCKMAP_RADIX1; ++i) {
 484                 isnew = ((i % HAMMER_BLOCKMAP_RADIX1_PERBUFFER) == 0);
 485                 layer1 = get_buffer_data(layer1_offset + i * sizeof(*layer1),
 486                                          &buffer, isnew);
 487                 bzero(layer1, sizeof(*layer1));
 488                 layer1->phys_offset = HAMMER_BLOCKMAP_UNAVAIL;
 489                 layer1->blocks_free = 0;
 490                 layer1->layer1_crc = crc32(layer1, HAMMER_LAYER1_CRCSIZE);
 491         }
 492         rel_buffer(buffer);
 493
 494         blockmap = &root_vol->ondisk->vol0_blockmap[HAMMER_ZONE_FREEMAP_INDEX];
 495         blockmap->phys_offset = layer1_offset;
 496         blockmap->alloc_offset = HAMMER_ENCODE_RAW_BUFFER(255, -1);
 497         blockmap->next_offset = HAMMER_ENCODE_RAW_BUFFER(0, 0);
 498         blockmap->reserved01 = 0;
 499         blockmap->entry_crc = crc32(blockmap, HAMMER_BLOCKMAP_CRCSIZE);
 500         root_vol->cache.modified = 1;
 501 }
 502
 503 /*
 504  * Load the volume's remaining free space into the freemap.
 505  *
 506  * Returns the number of big-blocks available.
 507  */
 508 int64_t
 509 initialize_freemap(struct volume_info *vol)
 510 {
 511         struct volume_info *root_vol;
 512         struct buffer_info *buffer1 = NULL;
 513         struct buffer_info *buffer2 = NULL;
 514         struct hammer_blockmap_layer1 *layer1;
 515         struct hammer_blockmap_layer2 *layer2;
 516         hammer_off_t layer1_base;
 517         hammer_off_t layer1_offset;
 518         hammer_off_t layer2_offset;
 519         hammer_off_t phys_offset;
 520         hammer_off_t aligned_vol_free_end;
 521         int64_t count = 0;
 522         int modified1 = 0;
 523
 524         root_vol = get_volume(RootVolNo);
 525         aligned_vol_free_end = (vol->vol_free_end + HAMMER_BLOCKMAP_LAYER2_MASK)
 526                                 & ~HAMMER_BLOCKMAP_LAYER2_MASK;
 527
 528         printf("initialize freemap volume %d\n", vol->vol_no);
 529
 530         /*
 531          * Initialize the freemap.  First preallocate the big-blocks required
 532          * to implement layer2.   This preallocation is a bootstrap allocation
 533          * using blocks from the target volume.
 534          */
 535         layer1_base = root_vol->ondisk->vol0_blockmap[
 536                                         HAMMER_ZONE_FREEMAP_INDEX].phys_offset;
 537         for (phys_offset = HAMMER_ENCODE_RAW_BUFFER(vol->vol_no, 0);
 538              phys_offset < aligned_vol_free_end;
 539              phys_offset += HAMMER_BLOCKMAP_LAYER2) {
 540                 layer1_offset = layer1_base +
 541                                 HAMMER_BLOCKMAP_LAYER1_OFFSET(phys_offset);
 542                 layer1 = get_buffer_data(layer1_offset, &buffer1, 0);
 543                 if (layer1->phys_offset == HAMMER_BLOCKMAP_UNAVAIL) {
 544                         layer1->phys_offset = alloc_bigblock(vol,
 545                                                 HAMMER_ZONE_FREEMAP_INDEX);
 546                         layer1->blocks_free = 0;
 547                         buffer1->cache.modified = 1;
 548                         layer1->layer1_crc = crc32(layer1,
 549                                                    HAMMER_LAYER1_CRCSIZE);
 550                 }
 551         }
 552
 553         /*
 554          * Now fill everything in.
 555          */
 556         for (phys_offset = HAMMER_ENCODE_RAW_BUFFER(vol->vol_no, 0);
 557              phys_offset < aligned_vol_free_end;
 558              phys_offset += HAMMER_BIGBLOCK_SIZE) {
 559                 modified1 = 0;
 560                 layer1_offset = layer1_base +
 561                                 HAMMER_BLOCKMAP_LAYER1_OFFSET(phys_offset);
 562                 layer1 = get_buffer_data(layer1_offset, &buffer1, 0);
 563
 564                 assert(layer1->phys_offset != HAMMER_BLOCKMAP_UNAVAIL);
 565                 layer2_offset = layer1->phys_offset +
 566                                 HAMMER_BLOCKMAP_LAYER2_OFFSET(phys_offset);
 567
 568                 layer2 = get_buffer_data(layer2_offset, &buffer2, 0);
 569                 bzero(layer2, sizeof(*layer2));
 570                 if (phys_offset < vol->vol_free_off) {
 571                         /*
 572                          * Fixups XXX - big-blocks already allocated as part
 573                          * of the freemap bootstrap.
 574                          */
 575                         if (layer2->zone == 0) {
 576                                 layer2->zone = HAMMER_ZONE_FREEMAP_INDEX;
 577                                 layer2->append_off = HAMMER_BIGBLOCK_SIZE;
 578                                 layer2->bytes_free = 0;
 579                         }
 580                 } else if (phys_offset < vol->vol_free_end) {
 581                         ++layer1->blocks_free;
 582                         buffer1->cache.modified = 1;
 583                         layer2->zone = 0;
 584                         layer2->append_off = 0;
 585                         layer2->bytes_free = HAMMER_BIGBLOCK_SIZE;
 586                         ++count;
 587                         modified1 = 1;
 588                 } else {
 589                         layer2->zone = HAMMER_ZONE_UNAVAIL_INDEX;
 590                         layer2->append_off = HAMMER_BIGBLOCK_SIZE;
 591                         layer2->bytes_free = 0;
 592                 }
 593                 layer2->entry_crc = crc32(layer2, HAMMER_LAYER2_CRCSIZE);
 594                 buffer2->cache.modified = 1;
 595
 596                 /*
 597                  * Finish-up layer 1
 598                  */
 599                 if (modified1) {
 600                         layer1->layer1_crc = crc32(layer1,
 601                                                    HAMMER_LAYER1_CRCSIZE);
 602                         buffer1->cache.modified = 1;
 603                 }
 604         }
 605         rel_buffer(buffer1);
 606         rel_buffer(buffer2);
 607         rel_volume(root_vol);
 608         return(count);
 609 }
 610
 611 /*
 612  * Returns the number of big-blocks available for filesystem data and undos
 613  * without formatting.
 614  */
 615 int64_t
 616 count_freemap(struct volume_info *vol)
 617 {
 618         hammer_off_t phys_offset;
 619         hammer_off_t vol_free_off;
 620         hammer_off_t aligned_vol_free_end;
 621         int64_t count = 0;
 622
 623         vol_free_off = HAMMER_ENCODE_RAW_BUFFER(vol->vol_no, 0);
 624         aligned_vol_free_end = (vol->vol_free_end + HAMMER_BLOCKMAP_LAYER2_MASK)
 625                                 & ~HAMMER_BLOCKMAP_LAYER2_MASK;
 626
 627         if (vol->vol_no == RootVolNo)
 628                 vol_free_off += HAMMER_BIGBLOCK_SIZE;
 629
 630         for (phys_offset = HAMMER_ENCODE_RAW_BUFFER(vol->vol_no, 0);
 631              phys_offset < aligned_vol_free_end;
 632              phys_offset += HAMMER_BLOCKMAP_LAYER2) {
 633                 vol_free_off += HAMMER_BIGBLOCK_SIZE;
 634         }
 635
 636         for (phys_offset = HAMMER_ENCODE_RAW_BUFFER(vol->vol_no, 0);
 637              phys_offset < aligned_vol_free_end;
 638              phys_offset += HAMMER_BIGBLOCK_SIZE) {
 639                 if (phys_offset < vol_free_off) {
 640                         ;
 641                 } else if (phys_offset < vol->vol_free_end) {
 642                         ++count;
 643                 }
 644         }
 645
 646         return(count);
 647 }
 648
 649 /*
 650  * Allocate big-blocks using our poor-man's volume->vol_free_off.
 651  *
 652  * If the zone is HAMMER_ZONE_FREEMAP_INDEX we are bootstrapping the freemap
 653  * itself and cannot update it yet.
 654  */
 655 hammer_off_t
 656 alloc_bigblock(struct volume_info *volume, int zone)
 657 {
 658         struct buffer_info *buffer1 = NULL;
 659         struct buffer_info *buffer2 = NULL;
 660         struct volume_info *root_vol;
 661         hammer_off_t result_offset;
 662         hammer_off_t layer_offset;
 663         struct hammer_blockmap_layer1 *layer1;
 664         struct hammer_blockmap_layer2 *layer2;
 665
 666         if (volume == NULL)
 667                 volume = get_volume(RootVolNo);
 668
 669         result_offset = volume->vol_free_off;
 670         if (result_offset >= volume->vol_free_end)
 671                 errx(1, "alloc_bigblock: Ran out of room, filesystem too small");
 672         volume->vol_free_off += HAMMER_BIGBLOCK_SIZE;
 673
 674         /*
 675          * Update the freemap.
 676          */
 677         if (zone != HAMMER_ZONE_FREEMAP_INDEX) {
 678                 root_vol = get_volume(RootVolNo);
 679                 layer_offset = root_vol->ondisk->vol0_blockmap[
 680                                         HAMMER_ZONE_FREEMAP_INDEX].phys_offset;
 681                 layer_offset += HAMMER_BLOCKMAP_LAYER1_OFFSET(result_offset);
 682                 layer1 = get_buffer_data(layer_offset, &buffer1, 0);
 683                 assert(layer1->phys_offset != HAMMER_BLOCKMAP_UNAVAIL);
 684                 --layer1->blocks_free;
 685                 layer1->layer1_crc = crc32(layer1, HAMMER_LAYER1_CRCSIZE);
 686                 buffer1->cache.modified = 1;
 687                 layer_offset = layer1->phys_offset +
 688                                HAMMER_BLOCKMAP_LAYER2_OFFSET(result_offset);
 689                 layer2 = get_buffer_data(layer_offset, &buffer2, 0);
 690                 assert(layer2->zone == 0);
 691                 layer2->zone = zone;
 692                 layer2->append_off = HAMMER_BIGBLOCK_SIZE;
 693                 layer2->bytes_free = 0;
 694                 layer2->entry_crc = crc32(layer2, HAMMER_LAYER2_CRCSIZE);
 695                 buffer2->cache.modified = 1;
 696
 697                 --root_vol->ondisk->vol0_stat_freebigblocks;
 698                 root_vol->cache.modified = 1;
 699
 700                 rel_buffer(buffer1);
 701                 rel_buffer(buffer2);
 702                 rel_volume(root_vol);
 703         }
 704
 705         rel_volume(volume);
 706         return(result_offset);
 707 }
 708
 709 /*
 710  * Format the undomap for the root volume.
 711  */
 712 void
 713 format_undomap(hammer_volume_ondisk_t ondisk)
 714 {
 715         const int undo_zone = HAMMER_ZONE_UNDO_INDEX;
 716         hammer_off_t undo_limit;
 717         hammer_blockmap_t blockmap;
 718         struct buffer_info *buffer = NULL;
 719         hammer_off_t scan;
 720         int n;
 721         int limit_index;
 722         u_int32_t seqno;
 723
 724         /*
 725          * Size the undo buffer in multiples of HAMMER_BIGBLOCK_SIZE,
 726          * up to HAMMER_UNDO_LAYER2 big-blocks.  Size to approximately
 727          * 0.1% of the disk.
 728          *
 729          * The minimum UNDO fifo size is 500MB, or approximately 1% of
 730          * the recommended 50G disk.
 731          *
 732          * Changing this minimum is rather dangerous as complex filesystem
 733          * operations can cause the UNDO FIFO to fill up otherwise.
 734          */
 735         undo_limit = UndoBufferSize;
 736         if (undo_limit == 0) {
 737                 undo_limit = (ondisk->vol_buf_end - ondisk->vol_buf_beg) / 1000;
 738                 if (undo_limit < 500*1024*1024)
 739                         undo_limit = 500*1024*1024;
 740         }
 741         undo_limit = (undo_limit + HAMMER_BIGBLOCK_MASK64) &
 742                      ~HAMMER_BIGBLOCK_MASK64;
 743         if (undo_limit < HAMMER_BIGBLOCK_SIZE)
 744                 undo_limit = HAMMER_BIGBLOCK_SIZE;
 745         if (undo_limit > HAMMER_BIGBLOCK_SIZE * HAMMER_UNDO_LAYER2)
 746                 undo_limit = HAMMER_BIGBLOCK_SIZE * HAMMER_UNDO_LAYER2;
 747         UndoBufferSize = undo_limit;
 748
 749         blockmap = &ondisk->vol0_blockmap[undo_zone];
 750         bzero(blockmap, sizeof(*blockmap));
 751         blockmap->phys_offset = HAMMER_BLOCKMAP_UNAVAIL;
 752         blockmap->first_offset = HAMMER_ZONE_ENCODE(undo_zone, 0);
 753         blockmap->next_offset = blockmap->first_offset;
 754         blockmap->alloc_offset = HAMMER_ZONE_ENCODE(undo_zone, undo_limit);
 755         blockmap->entry_crc = crc32(blockmap, HAMMER_BLOCKMAP_CRCSIZE);
 756
 757         n = 0;
 758         scan = blockmap->next_offset;
 759         limit_index = undo_limit / HAMMER_BIGBLOCK_SIZE;
 760
 761         assert(limit_index <= HAMMER_UNDO_LAYER2);
 762
 763         for (n = 0; n < limit_index; ++n) {
 764                 ondisk->vol0_undo_array[n] = alloc_bigblock(NULL,
 765                                                         HAMMER_ZONE_UNDO_INDEX);
 766                 scan += HAMMER_BIGBLOCK_SIZE;
 767         }
 768         while (n < HAMMER_UNDO_LAYER2) {
 769                 ondisk->vol0_undo_array[n] = HAMMER_BLOCKMAP_UNAVAIL;
 770                 ++n;
 771         }
 772
 773         /*
 774          * Pre-initialize the UNDO blocks (HAMMER version 4+)
 775          */
 776         printf("initializing the undo map (%jd MB)\n",
 777                 (intmax_t)(blockmap->alloc_offset & HAMMER_OFF_LONG_MASK) /
 778                 (1024 * 1024));
 779
 780         scan = blockmap->first_offset;
 781         seqno = 0;
 782
 783         while (scan < blockmap->alloc_offset) {
 784                 hammer_fifo_head_t head;
 785                 hammer_fifo_tail_t tail;
 786                 int isnew;
 787                 int bytes = HAMMER_UNDO_ALIGN;
 788
 789                 isnew = ((scan & HAMMER_BUFMASK64) == 0);
 790                 head = get_buffer_data(scan, &buffer, isnew);
 791                 buffer->cache.modified = 1;
 792                 tail = (void *)((char *)head + bytes - sizeof(*tail));
 793
 794                 bzero(head, bytes);
 795                 head->hdr_signature = HAMMER_HEAD_SIGNATURE;
 796                 head->hdr_type = HAMMER_HEAD_TYPE_DUMMY;
 797                 head->hdr_size = bytes;
 798                 head->hdr_seq = seqno++;
 799
 800                 tail->tail_signature = HAMMER_TAIL_SIGNATURE;
 801                 tail->tail_type = HAMMER_HEAD_TYPE_DUMMY;
 802                 tail->tail_size = bytes;
 803
 804                 head->hdr_crc = crc32(head, HAMMER_FIFO_HEAD_CRCOFF) ^
 805                                 crc32(head + 1, bytes - sizeof(*head));
 806
 807                 scan += bytes;
 808         }
 809         rel_buffer(buffer);
 810 }
 811
 812 /*
 813  * Format a new blockmap.  This is mostly a degenerate case because
 814  * all allocations are now actually done from the freemap.
 815  */
 816 void
 817 format_blockmap(hammer_blockmap_t blockmap, hammer_off_t zone_base)
 818 {
 819         blockmap->phys_offset = 0;
 820         blockmap->alloc_offset = HAMMER_ENCODE(zone_base, 255, -1);
 821         blockmap->first_offset = zone_base;
 822         blockmap->next_offset = zone_base;
 823         blockmap->entry_crc = crc32(blockmap, HAMMER_BLOCKMAP_CRCSIZE);
 824 }
 825
 826 /*
 827  * Allocate a chunk of data out of a blockmap.  This is a simplified
 828  * version which uses next_offset as a simple allocation iterator.
 829  */
 830 static
 831 void *
 832 alloc_blockmap(int zone, int bytes, hammer_off_t *result_offp,
 833                struct buffer_info **bufferp)
 834 {
 835         struct buffer_info *buffer1 = NULL;
 836         struct buffer_info *buffer2 = NULL;
 837         struct volume_info *volume;
 838         hammer_blockmap_t blockmap;
 839         hammer_blockmap_t freemap;
 840         struct hammer_blockmap_layer1 *layer1;
 841         struct hammer_blockmap_layer2 *layer2;
 842         hammer_off_t layer1_offset;
 843         hammer_off_t layer2_offset;
 844         hammer_off_t zone2_offset;
 845         void *ptr;
 846
 847         volume = get_volume(RootVolNo);
 848
 849         blockmap = &volume->ondisk->vol0_blockmap[zone];
 850         freemap = &volume->ondisk->vol0_blockmap[HAMMER_ZONE_FREEMAP_INDEX];
 851
 852         /*
 853          * Alignment and buffer-boundary issues.  If the allocation would
 854          * cross a buffer boundary we have to skip to the next buffer.
 855          */
 856         bytes = (bytes + 15) & ~15;
 857
 858 again:
 859         if ((blockmap->next_offset ^ (blockmap->next_offset + bytes - 1)) &
 860             ~HAMMER_BUFMASK64) {
 861                 volume->cache.modified = 1;
 862                 blockmap->next_offset = (blockmap->next_offset + bytes) &
 863                                         ~HAMMER_BUFMASK64;
 864         }
 865
 866         /*
 867          * Dive layer 1.  For now we can't allocate data outside of volume 0.
 868          */
 869         layer1_offset = freemap->phys_offset +
 870                         HAMMER_BLOCKMAP_LAYER1_OFFSET(blockmap->next_offset);
 871
 872         layer1 = get_buffer_data(layer1_offset, &buffer1, 0);
 873
 874         if (layer1->phys_offset == HAMMER_BLOCKMAP_UNAVAIL) {
 875                 fprintf(stderr, "alloc_blockmap: ran out of space!\n");
 876                 exit(1);
 877         }
 878
 879         /*
 880          * Dive layer 2
 881          */
 882         layer2_offset = layer1->phys_offset +
 883                         HAMMER_BLOCKMAP_LAYER2_OFFSET(blockmap->next_offset);
 884
 885         layer2 = get_buffer_data(layer2_offset, &buffer2, 0);
 886
 887         if (layer2->zone == HAMMER_ZONE_UNAVAIL_INDEX) {
 888                 fprintf(stderr, "alloc_blockmap: ran out of space!\n");
 889                 exit(1);
 890         }
 891
 892         /*
 893          * If we are entering a new big-block assign ownership to our
 894          * zone.  If the big-block is owned by another zone skip it.
 895          */
 896         if (layer2->zone == 0) {
 897                 --layer1->blocks_free;
 898                 layer2->zone = zone;
 899                 assert(layer2->bytes_free == HAMMER_BIGBLOCK_SIZE);
 900                 assert(layer2->append_off == 0);
 901         }
 902         if (layer2->zone != zone) {
 903                 blockmap->next_offset = (blockmap->next_offset + HAMMER_BIGBLOCK_SIZE) &
 904                                         ~HAMMER_BIGBLOCK_MASK64;
 905                 goto again;
 906         }
 907
 908         buffer1->cache.modified = 1;
 909         buffer2->cache.modified = 1;
 910         volume->cache.modified = 1;
 911         assert(layer2->append_off ==
 912                (blockmap->next_offset & HAMMER_BIGBLOCK_MASK));
 913         layer2->bytes_free -= bytes;
 914         *result_offp = blockmap->next_offset;
 915         blockmap->next_offset += bytes;
 916         layer2->append_off = (int)blockmap->next_offset &
 917                               HAMMER_BIGBLOCK_MASK;
 918
 919         layer1->layer1_crc = crc32(layer1, HAMMER_LAYER1_CRCSIZE);
 920         layer2->entry_crc = crc32(layer2, HAMMER_LAYER2_CRCSIZE);
 921
 922         zone2_offset = HAMMER_ZONE_ENCODE(zone,
 923                         *result_offp & ~HAMMER_OFF_ZONE_MASK);
 924
 925         ptr = get_buffer_data(zone2_offset, bufferp, 0);
 926         (*bufferp)->cache.modified = 1;
 927
 928         rel_buffer(buffer1);
 929         rel_buffer(buffer2);
 930         rel_volume(volume);
 931         return(ptr);
 932 }
 933
 934 /*
 935  * Flush various tracking structures to disk
 936  */
 937 void
 938 flush_all_volumes(void)
 939 {
 940         struct volume_info *vol;
 941
 942         TAILQ_FOREACH(vol, &VolList, entry)
 943                 flush_volume(vol);
 944 }
 945
 946 void
 947 flush_volume(struct volume_info *volume)
 948 {
 949         struct buffer_info *buffer;
 950         int i;
 951
 952         for (i = 0; i < HAMMER_BUFLISTS; ++i) {
 953                 TAILQ_FOREACH(buffer, &volume->buffer_lists[i], entry)
 954                         flush_buffer(buffer);
 955         }
 956         writehammerbuf(volume, volume->ondisk, 0);
 957         volume->cache.modified = 0;
 958 }
 959
 960 void
 961 flush_buffer(struct buffer_info *buffer)
 962 {
 963         writehammerbuf(buffer->volume, buffer->ondisk, buffer->raw_offset);
 964         buffer->cache.modified = 0;
 965 }
 966
 967 #if 0
 968 /*
 969  * Generic buffer initialization
 970  */
 971 static void
 972 init_fifo_head(hammer_fifo_head_t head, u_int16_t hdr_type)
 973 {
 974         head->hdr_signature = HAMMER_HEAD_SIGNATURE;
 975         head->hdr_type = hdr_type;
 976         head->hdr_size = 0;
 977         head->hdr_crc = 0;
 978         head->hdr_seq = 0;
 979 }
 980
 981 #endif
 982
 983 #if 0
 984 /*
 985  * Core I/O operations
 986  */
 987 static void
 988 readhammerbuf(struct volume_info *vol, void *data, int64_t offset)
 989 {
 990         ssize_t n;
 991
 992         n = pread(vol->fd, data, HAMMER_BUFSIZE, offset);
 993         if (n != HAMMER_BUFSIZE)
 994                 err(1, "Read volume %d (%s)", vol->vol_no, vol->name);
 995 }
 996
 997 #endif
 998
 999 static void
1000 writehammerbuf(struct volume_info *vol, const void *data, int64_t offset)
1001 {
1002         ssize_t n;
1003
1004         n = pwrite(vol->fd, data, HAMMER_BUFSIZE, offset);
1005         if (n != HAMMER_BUFSIZE)
1006                 err(1, "Write volume %d (%s)", vol->vol_no, vol->name);
1007 }