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 #include <sys/buf2.h>
  43
  44 static int
  45 hammer_setup_device(struct vnode **devvpp, const char *dev_path, int ronly);
  46
  47 static void
  48 hammer_close_device(struct vnode **devvpp, int ronly);
  49
  50 static int
  51 hammer_format_volume_header(struct hammer_mount *hmp, struct vnode *devvp,
  52         const char *vol_name, int vol_no, int vol_count,
  53         int64_t vol_size, int64_t boot_area_size, int64_t mem_area_size);
  54
  55 static int
  56 hammer_clear_volume_header(struct vnode *devvp);
  57
  58 struct bigblock_stat {
  59         uint64_t total_bigblocks;
  60         uint64_t total_free_bigblocks;
  61         uint64_t counter;
  62 };
  63
  64 static int
  65 hammer_format_freemap(hammer_transaction_t trans, hammer_volume_t volume,
  66         struct bigblock_stat *stat);
  67
  68 static int
  69 hammer_free_freemap(hammer_transaction_t trans, hammer_volume_t volume,
  70         struct bigblock_stat *stat);
  71
  72 int
  73 hammer_ioc_volume_add(hammer_transaction_t trans, hammer_inode_t ip,
  74                 struct hammer_ioc_volume *ioc)
  75 {
  76         struct hammer_mount *hmp = trans->hmp;
  77         struct mount *mp = hmp->mp;
  78         hammer_volume_t volume;
  79         int error;
  80
  81         if (mp->mnt_flag & MNT_RDONLY) {
  82                 kprintf("Cannot add volume to read-only HAMMER filesystem\n");
  83                 return (EINVAL);
  84         }
  85
  86         if (hmp->nvolumes + 1 >= HAMMER_MAX_VOLUMES) {
  87                 kprintf("Max number of HAMMER volumes exceeded\n");
  88                 return (EINVAL);
  89         }
  90
  91         if (hammer_lock_ex_try(&hmp->volume_lock) != 0) {
  92                 kprintf("Another volume operation is in progress!\n");
  93                 return (EAGAIN);
  94         }
  95
  96         /*
  97          * Find an unused volume number.
  98          */
  99         int free_vol_no = 0;
 100         while (free_vol_no < HAMMER_MAX_VOLUMES &&
 101                RB_LOOKUP(hammer_vol_rb_tree, &hmp->rb_vols_root, free_vol_no)) {
 102                 ++free_vol_no;
 103         }
 104         if (free_vol_no >= HAMMER_MAX_VOLUMES) {
 105                 kprintf("Max number of HAMMER volumes exceeded\n");
 106                 hammer_unlock(&hmp->volume_lock);
 107                 return (EINVAL);
 108         }
 109
 110         struct vnode *devvp = NULL;
 111         error = hammer_setup_device(&devvp, ioc->device_name, 0);
 112         if (error)
 113                 goto end;
 114         KKASSERT(devvp);
 115         error = hammer_format_volume_header(
 116                 hmp,
 117                 devvp,
 118                 hmp->rootvol->ondisk->vol_name,
 119                 free_vol_no,
 120                 hmp->nvolumes+1,
 121                 ioc->vol_size,
 122                 ioc->boot_area_size,
 123                 ioc->mem_area_size);
 124         hammer_close_device(&devvp, 0);
 125         if (error)
 126                 goto end;
 127
 128         error = hammer_install_volume(hmp, ioc->device_name, NULL);
 129         if (error)
 130                 goto end;
 131
 132         hammer_sync_lock_sh(trans);
 133         hammer_lock_ex(&hmp->blkmap_lock);
 134
 135         ++hmp->nvolumes;
 136
 137         /*
 138          * Set each volumes new value of the vol_count field.
 139          */
 140         for (int vol_no = 0; vol_no < HAMMER_MAX_VOLUMES; ++vol_no) {
 141                 volume = hammer_get_volume(hmp, vol_no, &error);
 142                 if (volume == NULL && error == ENOENT) {
 143                         /*
 144                          * Skip unused volume numbers
 145                          */
 146                         error = 0;
 147                         continue;
 148                 }
 149                 KKASSERT(volume != NULL && error == 0);
 150                 hammer_modify_volume_field(trans, volume, vol_count);
 151                 volume->ondisk->vol_count = hmp->nvolumes;
 152                 hammer_modify_volume_done(volume);
 153
 154                 /*
 155                  * Only changes to the header of the root volume
 156                  * are automatically flushed to disk. For all
 157                  * other volumes that we modify we do it here.
 158                  *
 159                  * No interlock is needed, volume buffers are not
 160                  * messed with by bioops.
 161                  */
 162                 if (volume != trans->rootvol && volume->io.modified) {
 163                         hammer_crc_set_volume(volume->ondisk);
 164                         hammer_io_flush(&volume->io, 0);
 165                 }
 166
 167                 hammer_rel_volume(volume, 0);
 168         }
 169
 170         volume = hammer_get_volume(hmp, free_vol_no, &error);
 171         KKASSERT(volume != NULL && error == 0);
 172
 173         struct bigblock_stat stat;
 174         error = hammer_format_freemap(trans, volume, &stat);
 175         KKASSERT(error == 0);
 176
 177         /*
 178          * Increase the total number of bigblocks
 179          */
 180         hammer_modify_volume_field(trans, trans->rootvol,
 181                 vol0_stat_bigblocks);
 182         trans->rootvol->ondisk->vol0_stat_bigblocks += stat.total_bigblocks;
 183         hammer_modify_volume_done(trans->rootvol);
 184
 185         /*
 186          * Increase the number of free bigblocks
 187          * (including the copy in hmp)
 188          */
 189         hammer_modify_volume_field(trans, trans->rootvol,
 190                 vol0_stat_freebigblocks);
 191         trans->rootvol->ondisk->vol0_stat_freebigblocks += stat.total_free_bigblocks;
 192         hmp->copy_stat_freebigblocks =
 193                 trans->rootvol->ondisk->vol0_stat_freebigblocks;
 194         hammer_modify_volume_done(trans->rootvol);
 195
 196         hammer_rel_volume(volume, 0);
 197
 198         hammer_unlock(&hmp->blkmap_lock);
 199         hammer_sync_unlock(trans);
 200
 201         KKASSERT(error == 0);
 202 end:
 203         hammer_unlock(&hmp->volume_lock);
 204         if (error)
 205                 kprintf("An error occurred: %d\n", error);
 206         return (error);
 207 }
 208
 209
 210 /*
 211  * Remove a volume.
 212  */
 213 int
 214 hammer_ioc_volume_del(hammer_transaction_t trans, hammer_inode_t ip,
 215                 struct hammer_ioc_volume *ioc)
 216 {
 217         struct hammer_mount *hmp = trans->hmp;
 218         struct mount *mp = hmp->mp;
 219         hammer_volume_t volume;
 220         int error = 0;
 221
 222         if (mp->mnt_flag & MNT_RDONLY) {
 223                 kprintf("Cannot del volume from read-only HAMMER filesystem\n");
 224                 return (EINVAL);
 225         }
 226
 227         if (hammer_lock_ex_try(&hmp->volume_lock) != 0) {
 228                 kprintf("Another volume operation is in progress!\n");
 229                 return (EAGAIN);
 230         }
 231
 232         volume = NULL;
 233
 234         /*
 235          * find volume by volname
 236          */
 237         for (int vol_no = 0; vol_no < HAMMER_MAX_VOLUMES; ++vol_no) {
 238                 volume = hammer_get_volume(hmp, vol_no, &error);
 239                 if (volume == NULL && error == ENOENT) {
 240                         /*
 241                          * Skip unused volume numbers
 242                          */
 243                         error = 0;
 244                         continue;
 245                 }
 246                 KKASSERT(volume != NULL && error == 0);
 247                 if (strcmp(volume->vol_name, ioc->device_name) == 0) {
 248                         break;
 249                 }
 250                 hammer_rel_volume(volume, 0);
 251                 volume = NULL;
 252         }
 253
 254         if (volume == NULL) {
 255                 kprintf("Couldn't find volume\n");
 256                 error = EINVAL;
 257                 goto end;
 258         }
 259
 260         if (volume == trans->rootvol) {
 261                 kprintf("Cannot remove root-volume\n");
 262                 hammer_rel_volume(volume, 0);
 263                 error = EINVAL;
 264                 goto end;
 265         }
 266
 267         /*
 268          *
 269          */
 270
 271         hmp->volume_to_remove = volume->vol_no;
 272
 273         struct hammer_ioc_reblock reblock;
 274         bzero(&reblock, sizeof(reblock));
 275
 276         reblock.key_beg.localization = HAMMER_MIN_LOCALIZATION;
 277         reblock.key_beg.obj_id = HAMMER_MIN_OBJID;
 278         reblock.key_end.localization = HAMMER_MAX_LOCALIZATION;
 279         reblock.key_end.obj_id = HAMMER_MAX_OBJID;
 280         reblock.head.flags = HAMMER_IOC_DO_FLAGS;
 281         reblock.free_level = 0;
 282
 283         error = hammer_ioc_reblock(trans, ip, &reblock);
 284
 285         if (reblock.head.flags & HAMMER_IOC_HEAD_INTR) {
 286                 error = EINTR;
 287         }
 288
 289         if (error) {
 290                 if (error == EINTR) {
 291                         kprintf("reblock was interrupted\n");
 292                 } else {
 293                         kprintf("reblock failed: %d\n", error);
 294                 }
 295                 hmp->volume_to_remove = -1;
 296                 hammer_rel_volume(volume, 0);
 297                 goto end;
 298         }
 299
 300         /*
 301          * Sync filesystem
 302          */
 303         int count = 0;
 304         while (hammer_flusher_haswork(hmp)) {
 305                 hammer_flusher_sync(hmp);
 306                 ++count;
 307                 if (count >= 5) {
 308                         if (count == 5)
 309                                 kprintf("HAMMER: flushing.");
 310                         else
 311                                 kprintf(".");
 312                         tsleep(&count, 0, "hmrufl", hz);
 313                 }
 314                 if (count == 30) {
 315                         kprintf("giving up");
 316                         break;
 317                 }
 318         }
 319         kprintf("\n");
 320
 321         hammer_sync_lock_sh(trans);
 322         hammer_lock_ex(&hmp->blkmap_lock);
 323
 324         /*
 325          * We use stat later to update rootvol's bigblock stats
 326          */
 327         struct bigblock_stat stat;
 328         error = hammer_free_freemap(trans, volume, &stat);
 329         if (error) {
 330                 kprintf("Failed to free volume. Volume not empty!\n");
 331                 hmp->volume_to_remove = -1;
 332                 hammer_rel_volume(volume, 0);
 333                 hammer_unlock(&hmp->blkmap_lock);
 334                 hammer_sync_unlock(trans);
 335                 goto end;
 336         }
 337
 338         hmp->volume_to_remove = -1;
 339
 340         hammer_rel_volume(volume, 0);
 341
 342         /*
 343          * Unload buffers
 344          */
 345         RB_SCAN(hammer_buf_rb_tree, &hmp->rb_bufs_root, NULL,
 346                 hammer_unload_buffer, volume);
 347
 348         error = hammer_unload_volume(volume, NULL);
 349         if (error == -1) {
 350                 kprintf("Failed to unload volume\n");
 351                 hammer_unlock(&hmp->blkmap_lock);
 352                 hammer_sync_unlock(trans);
 353                 goto end;
 354         }
 355
 356         volume = NULL;
 357         --hmp->nvolumes;
 358
 359         /*
 360          * Set each volume's new value of the vol_count field.
 361          */
 362         for (int vol_no = 0; vol_no < HAMMER_MAX_VOLUMES; ++vol_no) {
 363                 volume = hammer_get_volume(hmp, vol_no, &error);
 364                 if (volume == NULL && error == ENOENT) {
 365                         /*
 366                          * Skip unused volume numbers
 367                          */
 368                         error = 0;
 369                         continue;
 370                 }
 371
 372                 KKASSERT(volume != NULL && error == 0);
 373                 hammer_modify_volume_field(trans, volume, vol_count);
 374                 volume->ondisk->vol_count = hmp->nvolumes;
 375                 hammer_modify_volume_done(volume);
 376
 377                 /*
 378                  * Only changes to the header of the root volume
 379                  * are automatically flushed to disk. For all
 380                  * other volumes that we modify we do it here.
 381                  *
 382                  * No interlock is needed, volume buffers are not
 383                  * messed with by bioops.
 384                  */
 385                 if (volume != trans->rootvol && volume->io.modified) {
 386                         hammer_crc_set_volume(volume->ondisk);
 387                         hammer_io_flush(&volume->io, 0);
 388                 }
 389
 390                 hammer_rel_volume(volume, 0);
 391         }
 392
 393         /*
 394          * Update the total number of bigblocks
 395          */
 396         hammer_modify_volume_field(trans, trans->rootvol,
 397                 vol0_stat_bigblocks);
 398         trans->rootvol->ondisk->vol0_stat_bigblocks -= stat.total_bigblocks;
 399         hammer_modify_volume_done(trans->rootvol);
 400
 401         /*
 402          * Update the number of free bigblocks
 403          * (including the copy in hmp)
 404          */
 405         hammer_modify_volume_field(trans, trans->rootvol,
 406                 vol0_stat_freebigblocks);
 407         trans->rootvol->ondisk->vol0_stat_freebigblocks -= stat.total_free_bigblocks;
 408         hmp->copy_stat_freebigblocks =
 409                 trans->rootvol->ondisk->vol0_stat_freebigblocks;
 410         hammer_modify_volume_done(trans->rootvol);
 411
 412
 413         hammer_unlock(&hmp->blkmap_lock);
 414         hammer_sync_unlock(trans);
 415
 416         /*
 417          * Erase the volume header of the removed device.
 418          *
 419          * This is to not accidentally mount the volume again.
 420          */
 421         struct vnode *devvp = NULL;
 422         error = hammer_setup_device(&devvp, ioc->device_name, 0);
 423         if (error) {
 424                 kprintf("Failed to open device: %s\n", ioc->device_name);
 425                 goto end;
 426         }
 427         KKASSERT(devvp);
 428         error = hammer_clear_volume_header(devvp);
 429         if (error) {
 430                 kprintf("Failed to clear volume header of device: %s\n",
 431                         ioc->device_name);
 432                 goto end;
 433         }
 434         hammer_close_device(&devvp, 0);
 435
 436         KKASSERT(error == 0);
 437 end:
 438         hammer_unlock(&hmp->volume_lock);
 439         return (error);
 440 }
 441
 442
 443 int
 444 hammer_ioc_volume_list(hammer_transaction_t trans, hammer_inode_t ip,
 445     struct hammer_ioc_volume_list *ioc)
 446 {
 447         struct hammer_mount *hmp = trans->hmp;
 448         hammer_volume_t volume;
 449         int error = 0;
 450         int i, cnt, len;
 451
 452         for (i = 0, cnt = 0; i < HAMMER_MAX_VOLUMES && cnt < ioc->nvols; i++) {
 453                 volume = hammer_get_volume(hmp, i, &error);
 454                 if (volume == NULL && error == ENOENT) {
 455                         error = 0;
 456                         continue;
 457                 }
 458                 KKASSERT(volume != NULL && error == 0);
 459
 460                 len = strlen(volume->vol_name) + 1;
 461                 KKASSERT(len <= MAXPATHLEN);
 462
 463                 error = copyout(volume->vol_name, ioc->vols[cnt].device_name,
 464                                 len);
 465                 if (error) {
 466                         hammer_rel_volume(volume, 0);
 467                         return (error);
 468                 }
 469                 cnt++;
 470                 hammer_rel_volume(volume, 0);
 471         }
 472         ioc->nvols = cnt;
 473
 474         return (error);
 475 }
 476
 477 /*
 478  * Iterate over all usable L1 entries of the volume and
 479  * the corresponding L2 entries.
 480  */
 481 static int
 482 hammer_iterate_l1l2_entries(hammer_transaction_t trans, hammer_volume_t volume,
 483         int (*callback)(hammer_transaction_t, hammer_volume_t, hammer_buffer_t*,
 484                 struct hammer_blockmap_layer1*, struct hammer_blockmap_layer2*,
 485                 hammer_off_t, hammer_off_t, void*),
 486         void *data)
 487 {
 488         struct hammer_mount *hmp = trans->hmp;
 489         hammer_blockmap_t freemap = &hmp->blockmap[HAMMER_ZONE_FREEMAP_INDEX];
 490         hammer_buffer_t buffer = NULL;
 491         int error = 0;
 492
 493         hammer_off_t phys_off;
 494         hammer_off_t block_off;
 495         hammer_off_t layer1_off;
 496         hammer_off_t layer2_off;
 497         hammer_off_t aligned_buf_end_off;
 498         struct hammer_blockmap_layer1 *layer1;
 499         struct hammer_blockmap_layer2 *layer2;
 500
 501         /*
 502          * Calculate the usable size of the volume, which
 503          * must be aligned at a bigblock (8 MB) boundary.
 504          */
 505         aligned_buf_end_off = (HAMMER_ENCODE_RAW_BUFFER(volume->ondisk->vol_no,
 506                 (volume->ondisk->vol_buf_end - volume->ondisk->vol_buf_beg)
 507                 & ~HAMMER_LARGEBLOCK_MASK64));
 508
 509         /*
 510          * Iterate the volume's address space in chunks of 4 TB, where each
 511          * chunk consists of at least one physically available 8 MB bigblock.
 512          *
 513          * For each chunk we need one L1 entry and one L2 bigblock.
 514          * We use the first bigblock of each chunk as L2 block.
 515          */
 516         for (phys_off = HAMMER_ENCODE_RAW_BUFFER(volume->ondisk->vol_no, 0);
 517              phys_off < aligned_buf_end_off;
 518              phys_off += HAMMER_BLOCKMAP_LAYER2) {
 519                 for (block_off = 0;
 520                      block_off < HAMMER_BLOCKMAP_LAYER2;
 521                      block_off += HAMMER_LARGEBLOCK_SIZE) {
 522                         layer2_off = phys_off +
 523                                 HAMMER_BLOCKMAP_LAYER2_OFFSET(block_off);
 524                         layer2 = hammer_bread(hmp, layer2_off, &error, &buffer);
 525                         if (error)
 526                                 goto end;
 527
 528                         error = callback(trans, volume, &buffer, NULL,
 529                                          layer2, phys_off, block_off, data);
 530                         if (error)
 531                                 goto end;
 532                 }
 533
 534                 layer1_off = freemap->phys_offset +
 535                                 HAMMER_BLOCKMAP_LAYER1_OFFSET(phys_off);
 536                 layer1 = hammer_bread(hmp, layer1_off, &error, &buffer);
 537                 if (error)
 538                         goto end;
 539
 540                 error = callback(trans, volume, &buffer, layer1, NULL,
 541                                  phys_off, 0, data);
 542                 if (error)
 543                         goto end;
 544         }
 545
 546 end:
 547         if (buffer) {
 548                 hammer_rel_buffer(buffer, 0);
 549                 buffer = NULL;
 550         }
 551
 552         return error;
 553 }
 554
 555
 556 static int
 557 format_callback(hammer_transaction_t trans, hammer_volume_t volume,
 558         hammer_buffer_t *bufferp,
 559         struct hammer_blockmap_layer1 *layer1,
 560         struct hammer_blockmap_layer2 *layer2,
 561         hammer_off_t phys_off,
 562         hammer_off_t block_off,
 563         void *data)
 564 {
 565         struct bigblock_stat *stat = (struct bigblock_stat*)data;
 566
 567         /*
 568          * Calculate the usable size of the volume, which must be aligned
 569          * at a bigblock (8 MB) boundary.
 570          */
 571         hammer_off_t aligned_buf_end_off;
 572         aligned_buf_end_off = (HAMMER_ENCODE_RAW_BUFFER(volume->ondisk->vol_no,
 573                 (volume->ondisk->vol_buf_end - volume->ondisk->vol_buf_beg)
 574                 & ~HAMMER_LARGEBLOCK_MASK64));
 575
 576         if (layer1) {
 577                 KKASSERT(layer1->phys_offset == HAMMER_BLOCKMAP_UNAVAIL);
 578
 579                 hammer_modify_buffer(trans, *bufferp, layer1, sizeof(*layer1));
 580                 bzero(layer1, sizeof(layer1));
 581                 layer1->phys_offset = phys_off;
 582                 layer1->blocks_free = stat->counter;
 583                 layer1->layer1_crc = crc32(layer1, HAMMER_LAYER1_CRCSIZE);
 584                 hammer_modify_buffer_done(*bufferp);
 585
 586                 stat->total_free_bigblocks += stat->counter;
 587                 stat->counter = 0; /* reset */
 588         } else if (layer2) {
 589                 hammer_modify_buffer(trans, *bufferp, layer2, sizeof(*layer2));
 590                 bzero(layer2, sizeof(*layer2));
 591
 592                 if (block_off == 0) {
 593                         /*
 594                          * The first entry represents the L2 bigblock itself.
 595                          */
 596                         layer2->zone = HAMMER_ZONE_FREEMAP_INDEX;
 597                         layer2->append_off = HAMMER_LARGEBLOCK_SIZE;
 598                         layer2->bytes_free = 0;
 599                         ++stat->total_bigblocks;
 600                 } else if (phys_off + block_off < aligned_buf_end_off) {
 601                         /*
 602                          * Available bigblock
 603                          */
 604                         layer2->zone = 0;
 605                         layer2->append_off = 0;
 606                         layer2->bytes_free = HAMMER_LARGEBLOCK_SIZE;
 607                         ++stat->total_bigblocks;
 608                         ++stat->counter;
 609                 } else {
 610                         /*
 611                          * Bigblock outside of physically available
 612                          * space
 613                          */
 614                         layer2->zone = HAMMER_ZONE_UNAVAIL_INDEX;
 615                         layer2->append_off = HAMMER_LARGEBLOCK_SIZE;
 616                         layer2->bytes_free = 0;
 617                 }
 618
 619                 layer2->entry_crc = crc32(layer2, HAMMER_LAYER2_CRCSIZE);
 620                 hammer_modify_buffer_done(*bufferp);
 621         } else {
 622                 KKASSERT(0);
 623         }
 624
 625         return 0;
 626 }
 627
 628 static int
 629 hammer_format_freemap(hammer_transaction_t trans, hammer_volume_t volume,
 630         struct bigblock_stat *stat)
 631 {
 632         stat->total_bigblocks = 0;
 633         stat->total_free_bigblocks = 0;
 634         stat->counter = 0;
 635         return hammer_iterate_l1l2_entries(trans, volume, format_callback, stat);
 636 }
 637
 638 static int
 639 free_callback(hammer_transaction_t trans, hammer_volume_t volume __unused,
 640         hammer_buffer_t *bufferp,
 641         struct hammer_blockmap_layer1 *layer1,
 642         struct hammer_blockmap_layer2 *layer2,
 643         hammer_off_t phys_off,
 644         hammer_off_t block_off __unused,
 645         void *data)
 646 {
 647         struct bigblock_stat *stat = (struct bigblock_stat*)data;
 648
 649         /*
 650          * No modifications to ondisk structures
 651          */
 652         int testonly = (stat == NULL);
 653
 654         if (layer1) {
 655                 if (layer1->phys_offset == HAMMER_BLOCKMAP_UNAVAIL) {
 656                         /*
 657                          * This layer1 entry is already free.
 658                          */
 659                         return 0;
 660                 }
 661
 662                 KKASSERT((int)HAMMER_VOL_DECODE(layer1->phys_offset) ==
 663                         trans->hmp->volume_to_remove);
 664
 665                 if (testonly)
 666                         return 0;
 667
 668                 /*
 669                  * Free the L1 entry
 670                  */
 671                 hammer_modify_buffer(trans, *bufferp, layer1, sizeof(*layer1));
 672                 bzero(layer1, sizeof(layer1));
 673                 layer1->phys_offset = HAMMER_BLOCKMAP_UNAVAIL;
 674                 layer1->layer1_crc = crc32(layer1, HAMMER_LAYER1_CRCSIZE);
 675                 hammer_modify_buffer_done(*bufferp);
 676
 677                 return 0;
 678         } else if (layer2) {
 679                 if (layer2->zone == HAMMER_ZONE_UNAVAIL_INDEX) {
 680                         return 0;
 681                 }
 682
 683                 if (layer2->zone == HAMMER_ZONE_FREEMAP_INDEX) {
 684                         if (stat) {
 685                                 ++stat->total_bigblocks;
 686                         }
 687                         return 0;
 688                 }
 689
 690                 if (layer2->append_off == 0 &&
 691                     layer2->bytes_free == HAMMER_LARGEBLOCK_SIZE) {
 692                         if (stat) {
 693                                 ++stat->total_bigblocks;
 694                                 ++stat->total_free_bigblocks;
 695                         }
 696                         return 0;
 697                 }
 698
 699                 /*
 700                  * We found a layer2 entry that is not empty!
 701                  */
 702                 return EBUSY;
 703         } else {
 704                 KKASSERT(0);
 705         }
 706
 707         return EINVAL;
 708 }
 709
 710 static int
 711 hammer_free_freemap(hammer_transaction_t trans, hammer_volume_t volume,
 712         struct bigblock_stat *stat)
 713 {
 714         int error;
 715
 716         stat->total_bigblocks = 0;
 717         stat->total_free_bigblocks = 0;
 718         stat->counter = 0;
 719
 720         error = hammer_iterate_l1l2_entries(trans, volume, free_callback, NULL);
 721         if (error)
 722                 return error;
 723
 724         error = hammer_iterate_l1l2_entries(trans, volume, free_callback, stat);
 725         return error;
 726 }
 727
 728 /************************************************************************
 729  *                              MISC                                    *
 730  ************************************************************************
 731  */
 732
 733 static int
 734 hammer_setup_device(struct vnode **devvpp, const char *dev_path, int ronly)
 735 {
 736         int error;
 737         struct nlookupdata nd;
 738
 739         /*
 740          * Get the device vnode
 741          */
 742         if (*devvpp == NULL) {
 743                 error = nlookup_init(&nd, dev_path, UIO_SYSSPACE, NLC_FOLLOW);
 744                 if (error == 0)
 745                         error = nlookup(&nd);
 746                 if (error == 0)
 747                         error = cache_vref(&nd.nl_nch, nd.nl_cred, devvpp);
 748                 nlookup_done(&nd);
 749         } else {
 750                 error = 0;
 751         }
 752
 753         if (error == 0) {
 754                 if (vn_isdisk(*devvpp, &error)) {
 755                         error = vfs_mountedon(*devvpp);
 756                 }
 757         }
 758         if (error == 0 && vcount(*devvpp) > 0)
 759                 error = EBUSY;
 760         if (error == 0) {
 761                 vn_lock(*devvpp, LK_EXCLUSIVE | LK_RETRY);
 762                 error = vinvalbuf(*devvpp, V_SAVE, 0, 0);
 763                 if (error == 0) {
 764                         error = VOP_OPEN(*devvpp,
 765                                          (ronly ? FREAD : FREAD|FWRITE),
 766                                          FSCRED, NULL);
 767                 }
 768                 vn_unlock(*devvpp);
 769         }
 770         if (error && *devvpp) {
 771                 vrele(*devvpp);
 772                 *devvpp = NULL;
 773         }
 774         return (error);
 775 }
 776
 777 static void
 778 hammer_close_device(struct vnode **devvpp, int ronly)
 779 {
 780         if (*devvpp) {
 781                 vinvalbuf(*devvpp, ronly ? 0 : V_SAVE, 0, 0);
 782                 VOP_CLOSE(*devvpp, (ronly ? FREAD : FREAD|FWRITE));
 783                 vrele(*devvpp);
 784                 *devvpp = NULL;
 785         }
 786 }
 787
 788 static int
 789 hammer_format_volume_header(struct hammer_mount *hmp, struct vnode *devvp,
 790         const char *vol_name, int vol_no, int vol_count,
 791         int64_t vol_size, int64_t boot_area_size, int64_t mem_area_size)
 792 {
 793         struct buf *bp = NULL;
 794         struct hammer_volume_ondisk *ondisk;
 795         int error;
 796
 797         /*
 798          * Extract the volume number from the volume header and do various
 799          * sanity checks.
 800          */
 801         KKASSERT(HAMMER_BUFSIZE >= sizeof(struct hammer_volume_ondisk));
 802         error = bread(devvp, 0LL, HAMMER_BUFSIZE, &bp);
 803         if (error || bp->b_bcount < sizeof(struct hammer_volume_ondisk))
 804                 goto late_failure;
 805
 806         ondisk = (struct hammer_volume_ondisk*) bp->b_data;
 807
 808         /*
 809          * Note that we do NOT allow to use a device that contains
 810          * a valid HAMMER signature. It has to be cleaned up with dd
 811          * before.
 812          */
 813         if (ondisk->vol_signature == HAMMER_FSBUF_VOLUME) {
 814                 kprintf("hammer_volume_add: Formatting of valid HAMMER volume "
 815                         "%s denied. Erase with dd!\n", vol_name);
 816                 error = EFTYPE;
 817                 goto late_failure;
 818         }
 819
 820         bzero(ondisk, sizeof(struct hammer_volume_ondisk));
 821         ksnprintf(ondisk->vol_name, sizeof(ondisk->vol_name), "%s", vol_name);
 822         ondisk->vol_fstype = hmp->rootvol->ondisk->vol_fstype;
 823         ondisk->vol_signature = HAMMER_FSBUF_VOLUME;
 824         ondisk->vol_fsid = hmp->fsid;
 825         ondisk->vol_rootvol = hmp->rootvol->vol_no;
 826         ondisk->vol_no = vol_no;
 827         ondisk->vol_count = vol_count;
 828         ondisk->vol_version = hmp->version;
 829
 830         /*
 831          * Reserve space for (future) header junk, setup our poor-man's
 832          * bigblock allocator.
 833          */
 834         int64_t vol_alloc = HAMMER_BUFSIZE * 16;
 835
 836         ondisk->vol_bot_beg = vol_alloc;
 837         vol_alloc += boot_area_size;
 838         ondisk->vol_mem_beg = vol_alloc;
 839         vol_alloc += mem_area_size;
 840
 841         /*
 842          * The remaining area is the zone 2 buffer allocation area.  These
 843          * buffers
 844          */
 845         ondisk->vol_buf_beg = vol_alloc;
 846         ondisk->vol_buf_end = vol_size & ~(int64_t)HAMMER_BUFMASK;
 847
 848         if (ondisk->vol_buf_end < ondisk->vol_buf_beg) {
 849                 kprintf("volume %d %s is too small to hold the volume header",
 850                      ondisk->vol_no, ondisk->vol_name);
 851                 error = EFTYPE;
 852                 goto late_failure;
 853         }
 854
 855         ondisk->vol_nblocks = (ondisk->vol_buf_end - ondisk->vol_buf_beg) /
 856                               HAMMER_BUFSIZE;
 857         ondisk->vol_blocksize = HAMMER_BUFSIZE;
 858
 859         /*
 860          * Write volume header to disk
 861          */
 862         error = bwrite(bp);
 863         bp = NULL;
 864
 865 late_failure:
 866         if (bp)
 867                 brelse(bp);
 868         return (error);
 869 }
 870
 871 /*
 872  * Invalidates the volume header. Used by volume-del.
 873  */
 874 static int
 875 hammer_clear_volume_header(struct vnode *devvp)
 876 {
 877         struct buf *bp = NULL;
 878         struct hammer_volume_ondisk *ondisk;
 879         int error;
 880
 881         KKASSERT(HAMMER_BUFSIZE >= sizeof(struct hammer_volume_ondisk));
 882         error = bread(devvp, 0LL, HAMMER_BUFSIZE, &bp);
 883         if (error || bp->b_bcount < sizeof(struct hammer_volume_ondisk))
 884                 goto late_failure;
 885
 886         ondisk = (struct hammer_volume_ondisk*) bp->b_data;
 887         bzero(ondisk, sizeof(struct hammer_volume_ondisk));
 888
 889         error = bwrite(bp);
 890         bp = NULL;
 891
 892 late_failure:
 893         if (bp)
 894                 brelse(bp);
 895         return (error);
 896 }