sys/vfs/hammer/hammer_volume.c

   1 /*
   2  * Copyright (c) 2009 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> and
   6  * Michael Neumann <mneumann@ntecs.de>
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions
  10  * are met:
  11  *
  12  * 1. Redistributions of source code must retain the above copyright
  13  *    notice, this list of conditions and the following disclaimer.
  14  * 2. Redistributions in binary form must reproduce the above copyright
  15  *    notice, this list of conditions and the following disclaimer in
  16  *    the documentation and/or other materials provided with the
  17  *    distribution.
  18  * 3. Neither the name of The DragonFly Project nor the names of its
  19  *    contributors may be used to endorse or promote products derived
  20  *    from this software without specific, prior written permission.
  21  *
  22  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  23  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  24  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  25  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
  26  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
  27  * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
  28  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  29  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
  30  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  31  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
  32  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  33  * SUCH DAMAGE.
  34  *
  35  */
  36
  37 #include "hammer.h"
  38 #include <sys/fcntl.h>
  39 #include <sys/nlookup.h>
  40 #include <sys/buf.h>
  41
  42 static int
  43 hammer_setup_device(struct vnode **devvpp, const char *dev_path, int ronly);
  44
  45 static void
  46 hammer_close_device(struct vnode **devvpp, int ronly);
  47
  48 static int
  49 hammer_format_volume_header(struct hammer_mount *hmp, struct vnode *devvp,
  50         const char *vol_name, int vol_no, int vol_count,
  51         int64_t vol_size, int64_t boot_area_size, int64_t mem_area_size);
  52
  53 static int
  54 hammer_clear_volume_header(struct vnode *devvp);
  55
  56 struct bigblock_stat {
  57         uint64_t total_bigblocks;
  58         uint64_t total_free_bigblocks;
  59         uint64_t counter;
  60 };
  61
  62 static int
  63 hammer_format_freemap(hammer_transaction_t trans, hammer_volume_t volume,
  64         struct bigblock_stat *stat);
  65
  66 static int
  67 hammer_free_freemap(hammer_transaction_t trans, hammer_volume_t volume,
  68         struct bigblock_stat *stat);
  69
  70 int
  71 hammer_ioc_volume_add(hammer_transaction_t trans, hammer_inode_t ip,
  72                 struct hammer_ioc_volume *ioc)
  73 {
  74         struct hammer_mount *hmp = trans->hmp;
  75         struct mount *mp = hmp->mp;
  76         hammer_volume_t volume;
  77         int error;
  78
  79         if (mp->mnt_flag & MNT_RDONLY) {
  80                 kprintf("Cannot add volume to read-only HAMMER filesystem\n");
  81                 return (EINVAL);
  82         }
  83
  84         if (hmp->nvolumes + 1 >= HAMMER_MAX_VOLUMES) {
  85                 kprintf("Max number of HAMMER volumes exceeded\n");
  86                 return (EINVAL);
  87         }
  88
  89         if (hammer_lock_ex_try(&hmp->volume_lock) != 0) {
  90                 kprintf("Another volume operation is in progress!\n");
  91                 return (EAGAIN);
  92         }
  93
  94         /*
  95          * Find an unused volume number.
  96          */
  97         int free_vol_no = 0;
  98         while (free_vol_no < HAMMER_MAX_VOLUMES &&
  99                RB_LOOKUP(hammer_vol_rb_tree, &hmp->rb_vols_root, free_vol_no)) {
 100                 ++free_vol_no;
 101         }
 102         if (free_vol_no >= HAMMER_MAX_VOLUMES) {
 103                 kprintf("Max number of HAMMER volumes exceeded\n");
 104                 hammer_unlock(&hmp->volume_lock);
 105                 return (EINVAL);
 106         }
 107
 108         struct vnode *devvp = NULL;
 109         error = hammer_setup_device(&devvp, ioc->device_name, 0);
 110         if (error)
 111                 goto end;
 112         KKASSERT(devvp);
 113         error = hammer_format_volume_header(
 114                 hmp,
 115                 devvp,
 116                 hmp->rootvol->ondisk->vol_name,
 117                 free_vol_no,
 118                 hmp->nvolumes+1,
 119                 ioc->vol_size,
 120                 ioc->boot_area_size,
 121                 ioc->mem_area_size);
 122         hammer_close_device(&devvp, 0);
 123         if (error)
 124                 goto end;
 125
 126         error = hammer_install_volume(hmp, ioc->device_name, NULL);
 127         if (error)
 128                 goto end;
 129
 130         hammer_sync_lock_sh(trans);
 131         hammer_lock_ex(&hmp->blkmap_lock);
 132
 133         ++hmp->nvolumes;
 134
 135         /*
 136          * Set each volumes new value of the vol_count field.
 137          */
 138         for (int vol_no = 0; vol_no < HAMMER_MAX_VOLUMES; ++vol_no) {
 139                 volume = hammer_get_volume(hmp, vol_no, &error);
 140                 if (volume == NULL && error == ENOENT) {
 141                         /*
 142                          * Skip unused volume numbers
 143                          */
 144                         error = 0;
 145                         continue;
 146                 }
 147                 KKASSERT(volume != NULL && error == 0);
 148                 hammer_modify_volume_field(trans, volume, vol_count);
 149                 volume->ondisk->vol_count = hmp->nvolumes;
 150                 hammer_modify_volume_done(volume);
 151
 152                 /*
 153                  * Only changes to the header of the root volume
 154                  * are automatically flushed to disk. For all
 155                  * other volumes that we modify we do it here.
 156                  *
 157                  * No interlock is needed, volume buffers are not
 158                  * messed with by bioops.
 159                  */
 160                 if (volume != trans->rootvol && volume->io.modified) {
 161                         hammer_crc_set_volume(volume->ondisk);
 162                         hammer_io_flush(&volume->io, 0);
 163                 }
 164
 165                 hammer_rel_volume(volume, 0);
 166         }
 167
 168         volume = hammer_get_volume(hmp, free_vol_no, &error);
 169         KKASSERT(volume != NULL && error == 0);
 170
 171         struct bigblock_stat stat;
 172         error = hammer_format_freemap(trans, volume, &stat);
 173         KKASSERT(error == 0);
 174
 175         /*
 176          * Increase the total number of bigblocks
 177          */
 178         hammer_modify_volume_field(trans, trans->rootvol,
 179                 vol0_stat_bigblocks);
 180         trans->rootvol->ondisk->vol0_stat_bigblocks += stat.total_bigblocks;
 181         hammer_modify_volume_done(trans->rootvol);
 182
 183         /*
 184          * Increase the number of free bigblocks
 185          * (including the copy in hmp)
 186          */
 187         hammer_modify_volume_field(trans, trans->rootvol,
 188                 vol0_stat_freebigblocks);
 189         trans->rootvol->ondisk->vol0_stat_freebigblocks += stat.total_free_bigblocks;
 190         hmp->copy_stat_freebigblocks =
 191                 trans->rootvol->ondisk->vol0_stat_freebigblocks;
 192         hammer_modify_volume_done(trans->rootvol);
 193
 194         hammer_rel_volume(volume, 0);
 195
 196         hammer_unlock(&hmp->blkmap_lock);
 197         hammer_sync_unlock(trans);
 198
 199         KKASSERT(error == 0);
 200 end:
 201         hammer_unlock(&hmp->volume_lock);
 202         if (error)
 203                 kprintf("An error occurred: %d\n", error);
 204         return (error);
 205 }
 206
 207
 208 /*
 209  * Remove a volume.
 210  */
 211 int
 212 hammer_ioc_volume_del(hammer_transaction_t trans, hammer_inode_t ip,
 213                 struct hammer_ioc_volume *ioc)
 214 {
 215         struct hammer_mount *hmp = trans->hmp;
 216         struct mount *mp = hmp->mp;
 217         hammer_volume_t volume;
 218         int error = 0;
 219
 220         if (mp->mnt_flag & MNT_RDONLY) {
 221                 kprintf("Cannot del volume from read-only HAMMER filesystem\n");
 222                 return (EINVAL);
 223         }
 224
 225         if (hammer_lock_ex_try(&hmp->volume_lock) != 0) {
 226                 kprintf("Another volume operation is in progress!\n");
 227                 return (EAGAIN);
 228         }
 229
 230         volume = NULL;
 231
 232         /*
 233          * find volume by volname
 234          */
 235         for (int vol_no = 0; vol_no < HAMMER_MAX_VOLUMES; ++vol_no) {
 236                 volume = hammer_get_volume(hmp, vol_no, &error);
 237                 if (volume == NULL && error == ENOENT) {
 238                         /*
 239                          * Skip unused volume numbers
 240                          */
 241                         error = 0;
 242                         continue;
 243                 }
 244                 KKASSERT(volume != NULL && error == 0);
 245                 if (strcmp(volume->vol_name, ioc->device_name) == 0) {
 246                         break;
 247                 }
 248                 hammer_rel_volume(volume, 0);
 249                 volume = NULL;
 250         }
 251
 252         if (volume == NULL) {
 253                 kprintf("Couldn't find volume\n");
 254                 error = EINVAL;
 255                 goto end;
 256         }
 257
 258         if (volume == trans->rootvol) {
 259                 kprintf("Cannot remove root-volume\n");
 260                 hammer_rel_volume(volume, 0);
 261                 error = EINVAL;
 262                 goto end;
 263         }
 264
 265         /*
 266          *
 267          */
 268
 269         hmp->volume_to_remove = volume->vol_no;
 270
 271         struct hammer_ioc_reblock reblock;
 272         bzero(&reblock, sizeof(reblock));
 273
 274         reblock.key_beg.localization = HAMMER_MIN_LOCALIZATION;
 275         reblock.key_beg.obj_id = HAMMER_MIN_OBJID;
 276         reblock.key_end.localization = HAMMER_MAX_LOCALIZATION;
 277         reblock.key_end.obj_id = HAMMER_MAX_OBJID;
 278         reblock.head.flags = HAMMER_IOC_DO_FLAGS;
 279         reblock.free_level = 0;
 280
 281         error = hammer_ioc_reblock(trans, ip, &reblock);
 282
 283         if (reblock.head.flags & HAMMER_IOC_HEAD_INTR) {
 284                 error = EINTR;
 285         }
 286
 287         if (error) {
 288                 if (error == EINTR) {
 289                         kprintf("reblock was interrupted\n");
 290                 } else {
 291                         kprintf("reblock failed: %d\n", error);
 292                 }
 293                 hmp->volume_to_remove = -1;
 294                 hammer_rel_volume(volume, 0);
 295                 goto end;
 296         }
 297
 298         /*
 299          * Sync filesystem
 300          */
 301         int count = 0;
 302         while (hammer_flusher_haswork(hmp)) {
 303                 hammer_flusher_sync(hmp);
 304                 ++count;
 305                 if (count >= 5) {
 306                         if (count == 5)
 307                                 kprintf("HAMMER: flushing.");
 308                         else
 309                                 kprintf(".");
 310                         tsleep(&count, 0, "hmrufl", hz);
 311                 }
 312                 if (count == 30) {
 313                         kprintf("giving up");
 314                         break;
 315                 }
 316         }
 317         kprintf("\n");
 318
 319         hammer_sync_lock_sh(trans);
 320         hammer_lock_ex(&hmp->blkmap_lock);
 321
 322         /*
 323          * We use stat later to update rootvol's bigblock stats
 324          */
 325         struct bigblock_stat stat;
 326         error = hammer_free_freemap(trans, volume, &stat);
 327         if (error) {
 328                 kprintf("Failed to free volume. Volume not empty!\n");
 329                 hmp->volume_to_remove = -1;
 330                 hammer_rel_volume(volume, 0);
 331                 hammer_unlock(&hmp->blkmap_lock);
 332                 hammer_sync_unlock(trans);
 333                 goto end;
 334         }
 335
 336         hmp->volume_to_remove = -1;
 337
 338         hammer_rel_volume(volume, 0);
 339
 340         /*
 341          * Unload buffers
 342          */
 343         RB_SCAN(hammer_buf_rb_tree, &hmp->rb_bufs_root, NULL,
 344                 hammer_unload_buffer, volume);
 345
 346         error = hammer_unload_volume(volume, NULL);
 347         if (error == -1) {
 348                 kprintf("Failed to unload volume\n");
 349                 hammer_unlock(&hmp->blkmap_lock);
 350                 hammer_sync_unlock(trans);
 351                 goto end;
 352         }
 353
 354         volume = NULL;
 355         --hmp->nvolumes;
 356
 357         /*
 358          * Set each volume's new value of the vol_count field.
 359          */
 360         for (int vol_no = 0; vol_no < HAMMER_MAX_VOLUMES; ++vol_no) {
 361                 volume = hammer_get_volume(hmp, vol_no, &error);
 362                 if (volume == NULL && error == ENOENT) {
 363                         /*
 364                          * Skip unused volume numbers
 365                          */
 366                         error = 0;
 367                         continue;
 368                 }
 369
 370                 KKASSERT(volume != NULL && error == 0);
 371                 hammer_modify_volume_field(trans, volume, vol_count);
 372                 volume->ondisk->vol_count = hmp->nvolumes;
 373                 hammer_modify_volume_done(volume);
 374
 375                 /*
 376                  * Only changes to the header of the root volume
 377                  * are automatically flushed to disk. For all
 378                  * other volumes that we modify we do it here.
 379                  *
 380                  * No interlock is needed, volume buffers are not
 381                  * messed with by bioops.
 382                  */
 383                 if (volume != trans->rootvol && volume->io.modified) {
 384                         hammer_crc_set_volume(volume->ondisk);
 385                         hammer_io_flush(&volume->io, 0);
 386                 }
 387
 388                 hammer_rel_volume(volume, 0);
 389         }
 390
 391         /*
 392          * Update the total number of bigblocks
 393          */
 394         hammer_modify_volume_field(trans, trans->rootvol,
 395                 vol0_stat_bigblocks);
 396         trans->rootvol->ondisk->vol0_stat_bigblocks -= stat.total_bigblocks;
 397         hammer_modify_volume_done(trans->rootvol);
 398
 399         /*
 400          * Update the number of free bigblocks
 401          * (including the copy in hmp)
 402          */
 403         hammer_modify_volume_field(trans, trans->rootvol,
 404                 vol0_stat_freebigblocks);
 405         trans->rootvol->ondisk->vol0_stat_freebigblocks -= stat.total_free_bigblocks;
 406         hmp->copy_stat_freebigblocks =
 407                 trans->rootvol->ondisk->vol0_stat_freebigblocks;
 408         hammer_modify_volume_done(trans->rootvol);
 409
 410
 411         hammer_unlock(&hmp->blkmap_lock);
 412         hammer_sync_unlock(trans);
 413
 414         /*
 415          * Erase the volume header of the removed device.
 416          *
 417          * This is to not accidentally mount the volume again.
 418          */
 419         struct vnode *devvp = NULL;
 420         error = hammer_setup_device(&devvp, ioc->device_name, 0);
 421         if (error) {
 422                 kprintf("Failed to open device: %s\n", ioc->device_name);
 423                 goto end;
 424         }
 425         KKASSERT(devvp);
 426         error = hammer_clear_volume_header(devvp);
 427         if (error) {
 428                 kprintf("Failed to clear volume header of device: %s\n",
 429                         ioc->device_name);
 430                 goto end;
 431         }
 432         hammer_close_device(&devvp, 0);
 433
 434         KKASSERT(error == 0);
 435 end:
 436         hammer_unlock(&hmp->volume_lock);
 437         return (error);
 438 }
 439
 440
 441 /*
 442  * Iterate over all usable L1 entries of the volume and
 443  * the corresponding L2 entries.
 444  */
 445 static int
 446 hammer_iterate_l1l2_entries(hammer_transaction_t trans, hammer_volume_t volume,
 447         int (*callback)(hammer_transaction_t, hammer_volume_t, hammer_buffer_t*,
 448                 struct hammer_blockmap_layer1*, struct hammer_blockmap_layer2*,
 449                 hammer_off_t, hammer_off_t, void*),
 450         void *data)
 451 {
 452         struct hammer_mount *hmp = trans->hmp;
 453         hammer_blockmap_t freemap = &hmp->blockmap[HAMMER_ZONE_FREEMAP_INDEX];
 454         hammer_buffer_t buffer = NULL;
 455         int error = 0;
 456
 457         hammer_off_t phys_off;
 458         hammer_off_t block_off;
 459         hammer_off_t layer1_off;
 460         hammer_off_t layer2_off;
 461         hammer_off_t aligned_buf_end_off;
 462         struct hammer_blockmap_layer1 *layer1;
 463         struct hammer_blockmap_layer2 *layer2;
 464
 465         /*
 466          * Calculate the usable size of the volume, which
 467          * must be aligned at a bigblock (8 MB) boundary.
 468          */
 469         aligned_buf_end_off = (HAMMER_ENCODE_RAW_BUFFER(volume->ondisk->vol_no,
 470                 (volume->ondisk->vol_buf_end - volume->ondisk->vol_buf_beg)
 471                 & ~HAMMER_LARGEBLOCK_MASK64));
 472
 473         /*
 474          * Iterate the volume's address space in chunks of 4 TB, where each
 475          * chunk consists of at least one physically available 8 MB bigblock.
 476          *
 477          * For each chunk we need one L1 entry and one L2 bigblock.
 478          * We use the first bigblock of each chunk as L2 block.
 479          */
 480         for (phys_off = HAMMER_ENCODE_RAW_BUFFER(volume->ondisk->vol_no, 0);
 481              phys_off < aligned_buf_end_off;
 482              phys_off += HAMMER_BLOCKMAP_LAYER2) {
 483                 for (block_off = 0;
 484                      block_off < HAMMER_BLOCKMAP_LAYER2;
 485                      block_off += HAMMER_LARGEBLOCK_SIZE) {
 486                         layer2_off = phys_off +
 487                                 HAMMER_BLOCKMAP_LAYER2_OFFSET(block_off);
 488                         layer2 = hammer_bread(hmp, layer2_off, &error, &buffer);
 489                         if (error)
 490                                 goto end;
 491
 492                         error = callback(trans, volume, &buffer, NULL,
 493                                          layer2, phys_off, block_off, data);
 494                         if (error)
 495                                 goto end;
 496                 }
 497
 498                 layer1_off = freemap->phys_offset +
 499                                 HAMMER_BLOCKMAP_LAYER1_OFFSET(phys_off);
 500                 layer1 = hammer_bread(hmp, layer1_off, &error, &buffer);
 501                 if (error)
 502                         goto end;
 503
 504                 error = callback(trans, volume, &buffer, layer1, NULL,
 505                                  phys_off, 0, data);
 506                 if (error)
 507                         goto end;
 508         }
 509
 510 end:
 511         if (buffer) {
 512                 hammer_rel_buffer(buffer, 0);
 513                 buffer = NULL;
 514         }
 515
 516         return error;
 517 }
 518
 519
 520 static int
 521 format_callback(hammer_transaction_t trans, hammer_volume_t volume,
 522         hammer_buffer_t *bufferp,
 523         struct hammer_blockmap_layer1 *layer1,
 524         struct hammer_blockmap_layer2 *layer2,
 525         hammer_off_t phys_off,
 526         hammer_off_t block_off,
 527         void *data)
 528 {
 529         struct bigblock_stat *stat = (struct bigblock_stat*)data;
 530
 531         /*
 532          * Calculate the usable size of the volume, which must be aligned
 533          * at a bigblock (8 MB) boundary.
 534          */
 535         hammer_off_t aligned_buf_end_off;
 536         aligned_buf_end_off = (HAMMER_ENCODE_RAW_BUFFER(volume->ondisk->vol_no,
 537                 (volume->ondisk->vol_buf_end - volume->ondisk->vol_buf_beg)
 538                 & ~HAMMER_LARGEBLOCK_MASK64));
 539
 540         if (layer1) {
 541                 KKASSERT(layer1->phys_offset == HAMMER_BLOCKMAP_UNAVAIL);
 542
 543                 hammer_modify_buffer(trans, *bufferp, layer1, sizeof(*layer1));
 544                 bzero(layer1, sizeof(layer1));
 545                 layer1->phys_offset = phys_off;
 546                 layer1->blocks_free = stat->counter;
 547                 layer1->layer1_crc = crc32(layer1, HAMMER_LAYER1_CRCSIZE);
 548                 hammer_modify_buffer_done(*bufferp);
 549
 550                 stat->total_free_bigblocks += stat->counter;
 551                 stat->counter = 0; /* reset */
 552         } else if (layer2) {
 553                 hammer_modify_buffer(trans, *bufferp, layer2, sizeof(*layer2));
 554                 bzero(layer2, sizeof(*layer2));
 555
 556                 if (block_off == 0) {
 557                         /*
 558                          * The first entry represents the L2 bigblock itself.
 559                          */
 560                         layer2->zone = HAMMER_ZONE_FREEMAP_INDEX;
 561                         layer2->append_off = HAMMER_LARGEBLOCK_SIZE;
 562                         layer2->bytes_free = 0;
 563                         ++stat->total_bigblocks;
 564                 } else if (phys_off + block_off < aligned_buf_end_off) {
 565                         /*
 566                          * Available bigblock
 567                          */
 568                         layer2->zone = 0;
 569                         layer2->append_off = 0;
 570                         layer2->bytes_free = HAMMER_LARGEBLOCK_SIZE;
 571                         ++stat->total_bigblocks;
 572                         ++stat->counter;
 573                 } else {
 574                         /*
 575                          * Bigblock outside of physically available
 576                          * space
 577                          */
 578                         layer2->zone = HAMMER_ZONE_UNAVAIL_INDEX;
 579                         layer2->append_off = HAMMER_LARGEBLOCK_SIZE;
 580                         layer2->bytes_free = 0;
 581                 }
 582
 583                 layer2->entry_crc = crc32(layer2, HAMMER_LAYER2_CRCSIZE);
 584                 hammer_modify_buffer_done(*bufferp);
 585         } else {
 586                 KKASSERT(0);
 587         }
 588
 589         return 0;
 590 }
 591
 592 static int
 593 hammer_format_freemap(hammer_transaction_t trans, hammer_volume_t volume,
 594         struct bigblock_stat *stat)
 595 {
 596         stat->total_bigblocks = 0;
 597         stat->total_free_bigblocks = 0;
 598         stat->counter = 0;
 599         return hammer_iterate_l1l2_entries(trans, volume, format_callback, stat);
 600 }
 601
 602 static int
 603 free_callback(hammer_transaction_t trans, hammer_volume_t volume __unused,
 604         hammer_buffer_t *bufferp,
 605         struct hammer_blockmap_layer1 *layer1,
 606         struct hammer_blockmap_layer2 *layer2,
 607         hammer_off_t phys_off,
 608         hammer_off_t block_off __unused,
 609         void *data)
 610 {
 611         struct bigblock_stat *stat = (struct bigblock_stat*)data;
 612
 613         /*
 614          * No modifications to ondisk structures
 615          */
 616         int testonly = (stat == NULL);
 617
 618         if (layer1) {
 619                 if (layer1->phys_offset == HAMMER_BLOCKMAP_UNAVAIL) {
 620                         /*
 621                          * This layer1 entry is already free.
 622                          */
 623                         return 0;
 624                 }
 625
 626                 KKASSERT((int)HAMMER_VOL_DECODE(layer1->phys_offset) ==
 627                         trans->hmp->volume_to_remove);
 628
 629                 if (testonly)
 630                         return 0;
 631
 632                 /*
 633                  * Free the L1 entry
 634                  */
 635                 hammer_modify_buffer(trans, *bufferp, layer1, sizeof(*layer1));
 636                 bzero(layer1, sizeof(layer1));
 637                 layer1->phys_offset = HAMMER_BLOCKMAP_UNAVAIL;
 638                 layer1->layer1_crc = crc32(layer1, HAMMER_LAYER1_CRCSIZE);
 639                 hammer_modify_buffer_done(*bufferp);
 640
 641                 return 0;
 642         } else if (layer2) {
 643                 if (layer2->zone == HAMMER_ZONE_UNAVAIL_INDEX) {
 644                         return 0;
 645                 }
 646
 647                 if (layer2->zone == HAMMER_ZONE_FREEMAP_INDEX) {
 648                         if (stat) {
 649                                 ++stat->total_bigblocks;
 650                         }
 651                         return 0;
 652                 }
 653
 654                 if (layer2->append_off == 0 &&
 655                     layer2->bytes_free == HAMMER_LARGEBLOCK_SIZE) {
 656                         if (stat) {
 657                                 ++stat->total_bigblocks;
 658                                 ++stat->total_free_bigblocks;
 659                         }
 660                         return 0;
 661                 }
 662
 663                 /*
 664                  * We found a layer2 entry that is not empty!
 665                  */
 666                 return EBUSY;
 667         } else {
 668                 KKASSERT(0);
 669         }
 670
 671         return EINVAL;
 672 }
 673
 674 static int
 675 hammer_free_freemap(hammer_transaction_t trans, hammer_volume_t volume,
 676         struct bigblock_stat *stat)
 677 {
 678         int error;
 679
 680         stat->total_bigblocks = 0;
 681         stat->total_free_bigblocks = 0;
 682         stat->counter = 0;
 683
 684         error = hammer_iterate_l1l2_entries(trans, volume, free_callback, NULL);
 685         if (error)
 686                 return error;
 687
 688         error = hammer_iterate_l1l2_entries(trans, volume, free_callback, stat);
 689         return error;
 690 }
 691
 692 /************************************************************************
 693  *                              MISC                                    *
 694  ************************************************************************
 695  */
 696
 697 static int
 698 hammer_setup_device(struct vnode **devvpp, const char *dev_path, int ronly)
 699 {
 700         int error;
 701         struct nlookupdata nd;
 702
 703         /*
 704          * Get the device vnode
 705          */
 706         if (*devvpp == NULL) {
 707                 error = nlookup_init(&nd, dev_path, UIO_SYSSPACE, NLC_FOLLOW);
 708                 if (error == 0)
 709                         error = nlookup(&nd);
 710                 if (error == 0)
 711                         error = cache_vref(&nd.nl_nch, nd.nl_cred, devvpp);
 712                 nlookup_done(&nd);
 713         } else {
 714                 error = 0;
 715         }
 716
 717         if (error == 0) {
 718                 if (vn_isdisk(*devvpp, &error)) {
 719                         error = vfs_mountedon(*devvpp);
 720                 }
 721         }
 722         if (error == 0 && vcount(*devvpp) > 0)
 723                 error = EBUSY;
 724         if (error == 0) {
 725                 vn_lock(*devvpp, LK_EXCLUSIVE | LK_RETRY);
 726                 error = vinvalbuf(*devvpp, V_SAVE, 0, 0);
 727                 if (error == 0) {
 728                         error = VOP_OPEN(*devvpp,
 729                                          (ronly ? FREAD : FREAD|FWRITE),
 730                                          FSCRED, NULL);
 731                 }
 732                 vn_unlock(*devvpp);
 733         }
 734         if (error && *devvpp) {
 735                 vrele(*devvpp);
 736                 *devvpp = NULL;
 737         }
 738         return (error);
 739 }
 740
 741 static void
 742 hammer_close_device(struct vnode **devvpp, int ronly)
 743 {
 744         VOP_CLOSE(*devvpp, (ronly ? FREAD : FREAD|FWRITE));
 745         if (*devvpp) {
 746                 vinvalbuf(*devvpp, ronly ? 0 : V_SAVE, 0, 0);
 747                 vrele(*devvpp);
 748                 *devvpp = NULL;
 749         }
 750 }
 751
 752 static int
 753 hammer_format_volume_header(struct hammer_mount *hmp, struct vnode *devvp,
 754         const char *vol_name, int vol_no, int vol_count,
 755         int64_t vol_size, int64_t boot_area_size, int64_t mem_area_size)
 756 {
 757         struct buf *bp = NULL;
 758         struct hammer_volume_ondisk *ondisk;
 759         int error;
 760
 761         /*
 762          * Extract the volume number from the volume header and do various
 763          * sanity checks.
 764          */
 765         KKASSERT(HAMMER_BUFSIZE >= sizeof(struct hammer_volume_ondisk));
 766         error = bread(devvp, 0LL, HAMMER_BUFSIZE, &bp);
 767         if (error || bp->b_bcount < sizeof(struct hammer_volume_ondisk))
 768                 goto late_failure;
 769
 770         ondisk = (struct hammer_volume_ondisk*) bp->b_data;
 771
 772         /*
 773          * Note that we do NOT allow to use a device that contains
 774          * a valid HAMMER signature. It has to be cleaned up with dd
 775          * before.
 776          */
 777         if (ondisk->vol_signature == HAMMER_FSBUF_VOLUME) {
 778                 kprintf("hammer_volume_add: Formatting of valid HAMMER volume "
 779                         "%s denied. Erase with dd!\n", vol_name);
 780                 error = EFTYPE;
 781                 goto late_failure;
 782         }
 783
 784         bzero(ondisk, sizeof(struct hammer_volume_ondisk));
 785         ksnprintf(ondisk->vol_name, sizeof(ondisk->vol_name), "%s", vol_name);
 786         ondisk->vol_fstype = hmp->rootvol->ondisk->vol_fstype;
 787         ondisk->vol_signature = HAMMER_FSBUF_VOLUME;
 788         ondisk->vol_fsid = hmp->fsid;
 789         ondisk->vol_rootvol = hmp->rootvol->vol_no;
 790         ondisk->vol_no = vol_no;
 791         ondisk->vol_count = vol_count;
 792         ondisk->vol_version = hmp->version;
 793
 794         /*
 795          * Reserve space for (future) header junk, setup our poor-man's
 796          * bigblock allocator.
 797          */
 798         int64_t vol_alloc = HAMMER_BUFSIZE * 16;
 799
 800         ondisk->vol_bot_beg = vol_alloc;
 801         vol_alloc += boot_area_size;
 802         ondisk->vol_mem_beg = vol_alloc;
 803         vol_alloc += mem_area_size;
 804
 805         /*
 806          * The remaining area is the zone 2 buffer allocation area.  These
 807          * buffers
 808          */
 809         ondisk->vol_buf_beg = vol_alloc;
 810         ondisk->vol_buf_end = vol_size & ~(int64_t)HAMMER_BUFMASK;
 811
 812         if (ondisk->vol_buf_end < ondisk->vol_buf_beg) {
 813                 kprintf("volume %d %s is too small to hold the volume header",
 814                      ondisk->vol_no, ondisk->vol_name);
 815                 error = EFTYPE;
 816                 goto late_failure;
 817         }
 818
 819         ondisk->vol_nblocks = (ondisk->vol_buf_end - ondisk->vol_buf_beg) /
 820                               HAMMER_BUFSIZE;
 821         ondisk->vol_blocksize = HAMMER_BUFSIZE;
 822
 823         /*
 824          * Write volume header to disk
 825          */
 826         error = bwrite(bp);
 827         bp = NULL;
 828
 829 late_failure:
 830         if (bp)
 831                 brelse(bp);
 832         return (error);
 833 }
 834
 835 /*
 836  * Invalidates the volume header. Used by volume-del.
 837  */
 838 static int
 839 hammer_clear_volume_header(struct vnode *devvp)
 840 {
 841         struct buf *bp = NULL;
 842         struct hammer_volume_ondisk *ondisk;
 843         int error;
 844
 845         KKASSERT(HAMMER_BUFSIZE >= sizeof(struct hammer_volume_ondisk));
 846         error = bread(devvp, 0LL, HAMMER_BUFSIZE, &bp);
 847         if (error || bp->b_bcount < sizeof(struct hammer_volume_ondisk))
 848                 goto late_failure;
 849
 850         ondisk = (struct hammer_volume_ondisk*) bp->b_data;
 851         bzero(ondisk, sizeof(struct hammer_volume_ondisk));
 852
 853         error = bwrite(bp);
 854         bp = NULL;
 855
 856 late_failure:
 857         if (bp)
 858                 brelse(bp);
 859         return (error);
 860 }