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