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 int
 442 hammer_ioc_volume_list(hammer_transaction_t trans, hammer_inode_t ip,
 443     struct hammer_ioc_volume_list *ioc)
 444 {
 445         struct hammer_mount *hmp = trans->hmp;
 446         hammer_volume_t volume;
 447         int error = 0;
 448         int i, cnt, len;
 449
 450         for (i = 0, cnt = 0; i < HAMMER_MAX_VOLUMES && cnt < ioc->nvols; i++) {
 451                 volume = hammer_get_volume(hmp, i, &error);
 452                 if (volume == NULL && error == ENOENT) {
 453                         error = 0;
 454                         continue;
 455                 }
 456                 KKASSERT(volume != NULL && error == 0);
 457
 458                 len = strlen(volume->vol_name) + 1;
 459                 KKASSERT(len <= MAXPATHLEN);
 460
 461                 error = copyout(volume->vol_name, ioc->vols[cnt].device_name,
 462                                 len);
 463                 if (error) {
 464                         hammer_rel_volume(volume, 0);
 465                         return (error);
 466                 }
 467                 cnt++;
 468                 hammer_rel_volume(volume, 0);
 469         }
 470         ioc->nvols = cnt;
 471
 472         return (error);
 473 }
 474
 475 /*
 476  * Iterate over all usable L1 entries of the volume and
 477  * the corresponding L2 entries.
 478  */
 479 static int
 480 hammer_iterate_l1l2_entries(hammer_transaction_t trans, hammer_volume_t volume,
 481         int (*callback)(hammer_transaction_t, hammer_volume_t, hammer_buffer_t*,
 482                 struct hammer_blockmap_layer1*, struct hammer_blockmap_layer2*,
 483                 hammer_off_t, hammer_off_t, void*),
 484         void *data)
 485 {
 486         struct hammer_mount *hmp = trans->hmp;
 487         hammer_blockmap_t freemap = &hmp->blockmap[HAMMER_ZONE_FREEMAP_INDEX];
 488         hammer_buffer_t buffer = NULL;
 489         int error = 0;
 490
 491         hammer_off_t phys_off;
 492         hammer_off_t block_off;
 493         hammer_off_t layer1_off;
 494         hammer_off_t layer2_off;
 495         hammer_off_t aligned_buf_end_off;
 496         struct hammer_blockmap_layer1 *layer1;
 497         struct hammer_blockmap_layer2 *layer2;
 498
 499         /*
 500          * Calculate the usable size of the volume, which
 501          * must be aligned at a bigblock (8 MB) boundary.
 502          */
 503         aligned_buf_end_off = (HAMMER_ENCODE_RAW_BUFFER(volume->ondisk->vol_no,
 504                 (volume->ondisk->vol_buf_end - volume->ondisk->vol_buf_beg)
 505                 & ~HAMMER_LARGEBLOCK_MASK64));
 506
 507         /*
 508          * Iterate the volume's address space in chunks of 4 TB, where each
 509          * chunk consists of at least one physically available 8 MB bigblock.
 510          *
 511          * For each chunk we need one L1 entry and one L2 bigblock.
 512          * We use the first bigblock of each chunk as L2 block.
 513          */
 514         for (phys_off = HAMMER_ENCODE_RAW_BUFFER(volume->ondisk->vol_no, 0);
 515              phys_off < aligned_buf_end_off;
 516              phys_off += HAMMER_BLOCKMAP_LAYER2) {
 517                 for (block_off = 0;
 518                      block_off < HAMMER_BLOCKMAP_LAYER2;
 519                      block_off += HAMMER_LARGEBLOCK_SIZE) {
 520                         layer2_off = phys_off +
 521                                 HAMMER_BLOCKMAP_LAYER2_OFFSET(block_off);
 522                         layer2 = hammer_bread(hmp, layer2_off, &error, &buffer);
 523                         if (error)
 524                                 goto end;
 525
 526                         error = callback(trans, volume, &buffer, NULL,
 527                                          layer2, phys_off, block_off, data);
 528                         if (error)
 529                                 goto end;
 530                 }
 531
 532                 layer1_off = freemap->phys_offset +
 533                                 HAMMER_BLOCKMAP_LAYER1_OFFSET(phys_off);
 534                 layer1 = hammer_bread(hmp, layer1_off, &error, &buffer);
 535                 if (error)
 536                         goto end;
 537
 538                 error = callback(trans, volume, &buffer, layer1, NULL,
 539                                  phys_off, 0, data);
 540                 if (error)
 541                         goto end;
 542         }
 543
 544 end:
 545         if (buffer) {
 546                 hammer_rel_buffer(buffer, 0);
 547                 buffer = NULL;
 548         }
 549
 550         return error;
 551 }
 552
 553
 554 static int
 555 format_callback(hammer_transaction_t trans, hammer_volume_t volume,
 556         hammer_buffer_t *bufferp,
 557         struct hammer_blockmap_layer1 *layer1,
 558         struct hammer_blockmap_layer2 *layer2,
 559         hammer_off_t phys_off,
 560         hammer_off_t block_off,
 561         void *data)
 562 {
 563         struct bigblock_stat *stat = (struct bigblock_stat*)data;
 564
 565         /*
 566          * Calculate the usable size of the volume, which must be aligned
 567          * at a bigblock (8 MB) boundary.
 568          */
 569         hammer_off_t aligned_buf_end_off;
 570         aligned_buf_end_off = (HAMMER_ENCODE_RAW_BUFFER(volume->ondisk->vol_no,
 571                 (volume->ondisk->vol_buf_end - volume->ondisk->vol_buf_beg)
 572                 & ~HAMMER_LARGEBLOCK_MASK64));
 573
 574         if (layer1) {
 575                 KKASSERT(layer1->phys_offset == HAMMER_BLOCKMAP_UNAVAIL);
 576
 577                 hammer_modify_buffer(trans, *bufferp, layer1, sizeof(*layer1));
 578                 bzero(layer1, sizeof(layer1));
 579                 layer1->phys_offset = phys_off;
 580                 layer1->blocks_free = stat->counter;
 581                 layer1->layer1_crc = crc32(layer1, HAMMER_LAYER1_CRCSIZE);
 582                 hammer_modify_buffer_done(*bufferp);
 583
 584                 stat->total_free_bigblocks += stat->counter;
 585                 stat->counter = 0; /* reset */
 586         } else if (layer2) {
 587                 hammer_modify_buffer(trans, *bufferp, layer2, sizeof(*layer2));
 588                 bzero(layer2, sizeof(*layer2));
 589
 590                 if (block_off == 0) {
 591                         /*
 592                          * The first entry represents the L2 bigblock itself.
 593                          */
 594                         layer2->zone = HAMMER_ZONE_FREEMAP_INDEX;
 595                         layer2->append_off = HAMMER_LARGEBLOCK_SIZE;
 596                         layer2->bytes_free = 0;
 597                         ++stat->total_bigblocks;
 598                 } else if (phys_off + block_off < aligned_buf_end_off) {
 599                         /*
 600                          * Available bigblock
 601                          */
 602                         layer2->zone = 0;
 603                         layer2->append_off = 0;
 604                         layer2->bytes_free = HAMMER_LARGEBLOCK_SIZE;
 605                         ++stat->total_bigblocks;
 606                         ++stat->counter;
 607                 } else {
 608                         /*
 609                          * Bigblock outside of physically available
 610                          * space
 611                          */
 612                         layer2->zone = HAMMER_ZONE_UNAVAIL_INDEX;
 613                         layer2->append_off = HAMMER_LARGEBLOCK_SIZE;
 614                         layer2->bytes_free = 0;
 615                 }
 616
 617                 layer2->entry_crc = crc32(layer2, HAMMER_LAYER2_CRCSIZE);
 618                 hammer_modify_buffer_done(*bufferp);
 619         } else {
 620                 KKASSERT(0);
 621         }
 622
 623         return 0;
 624 }
 625
 626 static int
 627 hammer_format_freemap(hammer_transaction_t trans, hammer_volume_t volume,
 628         struct bigblock_stat *stat)
 629 {
 630         stat->total_bigblocks = 0;
 631         stat->total_free_bigblocks = 0;
 632         stat->counter = 0;
 633         return hammer_iterate_l1l2_entries(trans, volume, format_callback, stat);
 634 }
 635
 636 static int
 637 free_callback(hammer_transaction_t trans, hammer_volume_t volume __unused,
 638         hammer_buffer_t *bufferp,
 639         struct hammer_blockmap_layer1 *layer1,
 640         struct hammer_blockmap_layer2 *layer2,
 641         hammer_off_t phys_off,
 642         hammer_off_t block_off __unused,
 643         void *data)
 644 {
 645         struct bigblock_stat *stat = (struct bigblock_stat*)data;
 646
 647         /*
 648          * No modifications to ondisk structures
 649          */
 650         int testonly = (stat == NULL);
 651
 652         if (layer1) {
 653                 if (layer1->phys_offset == HAMMER_BLOCKMAP_UNAVAIL) {
 654                         /*
 655                          * This layer1 entry is already free.
 656                          */
 657                         return 0;
 658                 }
 659
 660                 KKASSERT((int)HAMMER_VOL_DECODE(layer1->phys_offset) ==
 661                         trans->hmp->volume_to_remove);
 662
 663                 if (testonly)
 664                         return 0;
 665
 666                 /*
 667                  * Free the L1 entry
 668                  */
 669                 hammer_modify_buffer(trans, *bufferp, layer1, sizeof(*layer1));
 670                 bzero(layer1, sizeof(layer1));
 671                 layer1->phys_offset = HAMMER_BLOCKMAP_UNAVAIL;
 672                 layer1->layer1_crc = crc32(layer1, HAMMER_LAYER1_CRCSIZE);
 673                 hammer_modify_buffer_done(*bufferp);
 674
 675                 return 0;
 676         } else if (layer2) {
 677                 if (layer2->zone == HAMMER_ZONE_UNAVAIL_INDEX) {
 678                         return 0;
 679                 }
 680
 681                 if (layer2->zone == HAMMER_ZONE_FREEMAP_INDEX) {
 682                         if (stat) {
 683                                 ++stat->total_bigblocks;
 684                         }
 685                         return 0;
 686                 }
 687
 688                 if (layer2->append_off == 0 &&
 689                     layer2->bytes_free == HAMMER_LARGEBLOCK_SIZE) {
 690                         if (stat) {
 691                                 ++stat->total_bigblocks;
 692                                 ++stat->total_free_bigblocks;
 693                         }
 694                         return 0;
 695                 }
 696
 697                 /*
 698                  * We found a layer2 entry that is not empty!
 699                  */
 700                 return EBUSY;
 701         } else {
 702                 KKASSERT(0);
 703         }
 704
 705         return EINVAL;
 706 }
 707
 708 static int
 709 hammer_free_freemap(hammer_transaction_t trans, hammer_volume_t volume,
 710         struct bigblock_stat *stat)
 711 {
 712         int error;
 713
 714         stat->total_bigblocks = 0;
 715         stat->total_free_bigblocks = 0;
 716         stat->counter = 0;
 717
 718         error = hammer_iterate_l1l2_entries(trans, volume, free_callback, NULL);
 719         if (error)
 720                 return error;
 721
 722         error = hammer_iterate_l1l2_entries(trans, volume, free_callback, stat);
 723         return error;
 724 }
 725
 726 /************************************************************************
 727  *                              MISC                                    *
 728  ************************************************************************
 729  */
 730
 731 static int
 732 hammer_setup_device(struct vnode **devvpp, const char *dev_path, int ronly)
 733 {
 734         int error;
 735         struct nlookupdata nd;
 736
 737         /*
 738          * Get the device vnode
 739          */
 740         if (*devvpp == NULL) {
 741                 error = nlookup_init(&nd, dev_path, UIO_SYSSPACE, NLC_FOLLOW);
 742                 if (error == 0)
 743                         error = nlookup(&nd);
 744                 if (error == 0)
 745                         error = cache_vref(&nd.nl_nch, nd.nl_cred, devvpp);
 746                 nlookup_done(&nd);
 747         } else {
 748                 error = 0;
 749         }
 750
 751         if (error == 0) {
 752                 if (vn_isdisk(*devvpp, &error)) {
 753                         error = vfs_mountedon(*devvpp);
 754                 }
 755         }
 756         if (error == 0 && vcount(*devvpp) > 0)
 757                 error = EBUSY;
 758         if (error == 0) {
 759                 vn_lock(*devvpp, LK_EXCLUSIVE | LK_RETRY);
 760                 error = vinvalbuf(*devvpp, V_SAVE, 0, 0);
 761                 if (error == 0) {
 762                         error = VOP_OPEN(*devvpp,
 763                                          (ronly ? FREAD : FREAD|FWRITE),
 764                                          FSCRED, NULL);
 765                 }
 766                 vn_unlock(*devvpp);
 767         }
 768         if (error && *devvpp) {
 769                 vrele(*devvpp);
 770                 *devvpp = NULL;
 771         }
 772         return (error);
 773 }
 774
 775 static void
 776 hammer_close_device(struct vnode **devvpp, int ronly)
 777 {
 778         if (*devvpp) {
 779                 vinvalbuf(*devvpp, ronly ? 0 : V_SAVE, 0, 0);
 780                 VOP_CLOSE(*devvpp, (ronly ? FREAD : FREAD|FWRITE));
 781                 vrele(*devvpp);
 782                 *devvpp = NULL;
 783         }
 784 }
 785
 786 static int
 787 hammer_format_volume_header(struct hammer_mount *hmp, struct vnode *devvp,
 788         const char *vol_name, int vol_no, int vol_count,
 789         int64_t vol_size, int64_t boot_area_size, int64_t mem_area_size)
 790 {
 791         struct buf *bp = NULL;
 792         struct hammer_volume_ondisk *ondisk;
 793         int error;
 794
 795         /*
 796          * Extract the volume number from the volume header and do various
 797          * sanity checks.
 798          */
 799         KKASSERT(HAMMER_BUFSIZE >= sizeof(struct hammer_volume_ondisk));
 800         error = bread(devvp, 0LL, HAMMER_BUFSIZE, &bp);
 801         if (error || bp->b_bcount < sizeof(struct hammer_volume_ondisk))
 802                 goto late_failure;
 803
 804         ondisk = (struct hammer_volume_ondisk*) bp->b_data;
 805
 806         /*
 807          * Note that we do NOT allow to use a device that contains
 808          * a valid HAMMER signature. It has to be cleaned up with dd
 809          * before.
 810          */
 811         if (ondisk->vol_signature == HAMMER_FSBUF_VOLUME) {
 812                 kprintf("hammer_volume_add: Formatting of valid HAMMER volume "
 813                         "%s denied. Erase with dd!\n", vol_name);
 814                 error = EFTYPE;
 815                 goto late_failure;
 816         }
 817
 818         bzero(ondisk, sizeof(struct hammer_volume_ondisk));
 819         ksnprintf(ondisk->vol_name, sizeof(ondisk->vol_name), "%s", vol_name);
 820         ondisk->vol_fstype = hmp->rootvol->ondisk->vol_fstype;
 821         ondisk->vol_signature = HAMMER_FSBUF_VOLUME;
 822         ondisk->vol_fsid = hmp->fsid;
 823         ondisk->vol_rootvol = hmp->rootvol->vol_no;
 824         ondisk->vol_no = vol_no;
 825         ondisk->vol_count = vol_count;
 826         ondisk->vol_version = hmp->version;
 827
 828         /*
 829          * Reserve space for (future) header junk, setup our poor-man's
 830          * bigblock allocator.
 831          */
 832         int64_t vol_alloc = HAMMER_BUFSIZE * 16;
 833
 834         ondisk->vol_bot_beg = vol_alloc;
 835         vol_alloc += boot_area_size;
 836         ondisk->vol_mem_beg = vol_alloc;
 837         vol_alloc += mem_area_size;
 838
 839         /*
 840          * The remaining area is the zone 2 buffer allocation area.  These
 841          * buffers
 842          */
 843         ondisk->vol_buf_beg = vol_alloc;
 844         ondisk->vol_buf_end = vol_size & ~(int64_t)HAMMER_BUFMASK;
 845
 846         if (ondisk->vol_buf_end < ondisk->vol_buf_beg) {
 847                 kprintf("volume %d %s is too small to hold the volume header",
 848                      ondisk->vol_no, ondisk->vol_name);
 849                 error = EFTYPE;
 850                 goto late_failure;
 851         }
 852
 853         ondisk->vol_nblocks = (ondisk->vol_buf_end - ondisk->vol_buf_beg) /
 854                               HAMMER_BUFSIZE;
 855         ondisk->vol_blocksize = HAMMER_BUFSIZE;
 856
 857         /*
 858          * Write volume header to disk
 859          */
 860         error = bwrite(bp);
 861         bp = NULL;
 862
 863 late_failure:
 864         if (bp)
 865                 brelse(bp);
 866         return (error);
 867 }
 868
 869 /*
 870  * Invalidates the volume header. Used by volume-del.
 871  */
 872 static int
 873 hammer_clear_volume_header(struct vnode *devvp)
 874 {
 875         struct buf *bp = NULL;
 876         struct hammer_volume_ondisk *ondisk;
 877         int error;
 878
 879         KKASSERT(HAMMER_BUFSIZE >= sizeof(struct hammer_volume_ondisk));
 880         error = bread(devvp, 0LL, HAMMER_BUFSIZE, &bp);
 881         if (error || bp->b_bcount < sizeof(struct hammer_volume_ondisk))
 882                 goto late_failure;
 883
 884         ondisk = (struct hammer_volume_ondisk*) bp->b_data;
 885         bzero(ondisk, sizeof(struct hammer_volume_ondisk));
 886
 887         error = bwrite(bp);
 888         bp = NULL;
 889
 890 late_failure:
 891         if (bp)
 892                 brelse(bp);
 893         return (error);
 894 }