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