sys/vfs/hammer/hammer_reblock.c

   1 /*
   2  * Copyright (c) 2008 The DragonFly Project.  All rights reserved.
   3  *
   4  * This code is derived from software contributed to The DragonFly Project
   5  * by Matthew Dillon <dillon@backplane.com>
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  *
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in
  15  *    the documentation and/or other materials provided with the
  16  *    distribution.
  17  * 3. Neither the name of The DragonFly Project nor the names of its
  18  *    contributors may be used to endorse or promote products derived
  19  *    from this software without specific, prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  22  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  23  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  24  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
  25  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
  26  * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
  27  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  28  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
  29  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  30  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
  31  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  32  * SUCH DAMAGE.
  33  *
  34  * $DragonFly: src/sys/vfs/hammer/hammer_reblock.c,v 1.20 2008/06/21 20:21:58 dillon Exp $
  35  */
  36 /*
  37  * HAMMER reblocker - This code frees up fragmented physical space
  38  *
  39  * HAMMER only keeps track of free space on a big-block basis.  A big-block
  40  * containing holes can only be freed by migrating the remaining data in
  41  * that big-block into a new big-block, then freeing the big-block.
  42  *
  43  * This function is called from an ioctl or via the hammer support thread.
  44  */
  45
  46 #include "hammer.h"
  47
  48 static int hammer_reblock_helper(struct hammer_ioc_reblock *reblock,
  49                                  hammer_cursor_t cursor,
  50                                  hammer_btree_elm_t elm);
  51 static int hammer_reblock_data(struct hammer_ioc_reblock *reblock,
  52                                 hammer_cursor_t cursor, hammer_btree_elm_t elm);
  53 static int hammer_reblock_leaf_node(struct hammer_ioc_reblock *reblock,
  54                                 hammer_cursor_t cursor, hammer_btree_elm_t elm);
  55 static int hammer_reblock_int_node(struct hammer_ioc_reblock *reblock,
  56                                 hammer_cursor_t cursor, hammer_btree_elm_t elm);
  57
  58 int
  59 hammer_ioc_reblock(hammer_transaction_t trans, hammer_inode_t ip,
  60                struct hammer_ioc_reblock *reblock)
  61 {
  62         struct hammer_cursor cursor;
  63         hammer_btree_elm_t elm;
  64         int error;
  65
  66         if (reblock->beg_obj_id >= reblock->end_obj_id)
  67                 return(EINVAL);
  68         if (reblock->free_level < 0)
  69                 return(EINVAL);
  70
  71         reblock->cur_obj_id = reblock->beg_obj_id;
  72         reblock->cur_localization = reblock->beg_localization;
  73
  74 retry:
  75         error = hammer_init_cursor(trans, &cursor, NULL, NULL);
  76         if (error) {
  77                 hammer_done_cursor(&cursor);
  78                 return(error);
  79         }
  80         cursor.key_beg.localization = reblock->cur_localization;
  81         cursor.key_beg.obj_id = reblock->cur_obj_id;
  82         cursor.key_beg.key = HAMMER_MIN_KEY;
  83         cursor.key_beg.create_tid = 1;
  84         cursor.key_beg.delete_tid = 0;
  85         cursor.key_beg.rec_type = HAMMER_MIN_RECTYPE;
  86         cursor.key_beg.obj_type = 0;
  87
  88         cursor.key_end.localization = reblock->end_localization;
  89         cursor.key_end.obj_id = reblock->end_obj_id;
  90         cursor.key_end.key = HAMMER_MAX_KEY;
  91         cursor.key_end.create_tid = HAMMER_MAX_TID - 1;
  92         cursor.key_end.delete_tid = 0;
  93         cursor.key_end.rec_type = HAMMER_MAX_RECTYPE;
  94         cursor.key_end.obj_type = 0;
  95
  96         cursor.flags |= HAMMER_CURSOR_END_INCLUSIVE;
  97         cursor.flags |= HAMMER_CURSOR_BACKEND;
  98
  99         /*
 100          * This flag allows the btree scan code to return internal nodes,
 101          * so we can reblock them in addition to the leafs.  Only specify it
 102          * if we intend to reblock B-Tree nodes.
 103          */
 104         if (reblock->head.flags & HAMMER_IOC_DO_BTREE)
 105                 cursor.flags |= HAMMER_CURSOR_REBLOCKING;
 106
 107         error = hammer_btree_first(&cursor);
 108         while (error == 0) {
 109                 /*
 110                  * Internal or Leaf node
 111                  */
 112                 elm = &cursor.node->ondisk->elms[cursor.index];
 113                 reblock->cur_obj_id = elm->base.obj_id;
 114                 reblock->cur_localization = elm->base.localization;
 115
 116                 /*
 117                  * Yield to more important tasks
 118                  */
 119                 if ((error = hammer_signal_check(trans->hmp)) != 0)
 120                         break;
 121                 if (trans->hmp->sync_lock.wanted) {
 122                         tsleep(trans, 0, "hmrslo", hz / 10);
 123                 }
 124                 if (trans->hmp->locked_dirty_count +
 125                     trans->hmp->io_running_count > hammer_limit_dirtybufs) {
 126                         hammer_flusher_async(trans->hmp);
 127                         tsleep(trans, 0, "hmrslo", hz / 10);
 128                 }
 129
 130                 /*
 131                  * Acquiring the sync_lock prevents the operation from
 132                  * crossing a synchronization boundary.
 133                  *
 134                  * NOTE: cursor.node may have changed on return.
 135                  */
 136                 hammer_sync_lock_sh(trans);
 137                 error = hammer_reblock_helper(reblock, &cursor, elm);
 138                 hammer_sync_unlock(trans);
 139                 if (error == 0) {
 140                         cursor.flags |= HAMMER_CURSOR_ATEDISK;
 141                         error = hammer_btree_iterate(&cursor);
 142                 }
 143         }
 144         if (error == ENOENT)
 145                 error = 0;
 146         hammer_done_cursor(&cursor);
 147         if (error == EDEADLK)
 148                 goto retry;
 149         if (error == EINTR) {
 150                 reblock->head.flags |= HAMMER_IOC_HEAD_INTR;
 151                 error = 0;
 152         }
 153         return(error);
 154 }
 155
 156 /*
 157  * Reblock the B-Tree (leaf) node, record, and/or data if necessary.
 158  *
 159  * XXX We have no visibility into internal B-Tree nodes at the moment,
 160  * only leaf nodes.
 161  */
 162 static int
 163 hammer_reblock_helper(struct hammer_ioc_reblock *reblock,
 164                       hammer_cursor_t cursor, hammer_btree_elm_t elm)
 165 {
 166         hammer_mount_t hmp;
 167         hammer_off_t tmp_offset;
 168         int error;
 169         int bytes;
 170         int cur;
 171         int iocflags;
 172
 173         error = 0;
 174         hmp = cursor->trans->hmp;
 175
 176         /*
 177          * Reblock data.  Note that data embedded in a record is reblocked
 178          * by the record reblock code.  Data processing only occurs at leaf
 179          * nodes and for RECORD element types.
 180          */
 181         if (cursor->node->ondisk->type != HAMMER_BTREE_TYPE_LEAF)
 182                 goto skip;
 183         if (elm->leaf.base.btype != HAMMER_BTREE_TYPE_RECORD)
 184                 return(0);
 185         tmp_offset = elm->leaf.data_offset;
 186         if (tmp_offset == 0)
 187                 goto skip;
 188         if (error)
 189                 goto skip;
 190
 191         /*
 192          * NOTE: Localization restrictions may also have been set-up, we can't
 193          * just set the match flags willy-nilly here.
 194          */
 195         switch(elm->leaf.base.rec_type) {
 196         case HAMMER_RECTYPE_INODE:
 197                 iocflags = HAMMER_IOC_DO_INODES;
 198                 break;
 199         case HAMMER_RECTYPE_EXT:
 200         case HAMMER_RECTYPE_FIX:
 201         case HAMMER_RECTYPE_DIRENTRY:
 202                 iocflags = HAMMER_IOC_DO_DIRS;
 203                 break;
 204         case HAMMER_RECTYPE_DATA:
 205         case HAMMER_RECTYPE_DB:
 206                 iocflags = HAMMER_IOC_DO_DATA;
 207                 break;
 208         default:
 209                 iocflags = 0;
 210                 break;
 211         }
 212         if (reblock->head.flags & iocflags) {
 213                 ++reblock->data_count;
 214                 reblock->data_byte_count += elm->leaf.data_len;
 215                 bytes = hammer_blockmap_getfree(hmp, tmp_offset, &cur, &error);
 216                 if (hammer_debug_general & 0x4000)
 217                         kprintf("D %6d/%d\n", bytes, reblock->free_level);
 218                 if (error == 0 && (cur == 0 || reblock->free_level == 0) &&
 219                     bytes >= reblock->free_level) {
 220                         hammer_io_direct_uncache(hmp, &elm->leaf);
 221                         error = hammer_cursor_upgrade(cursor);
 222                         if (error == 0) {
 223                                 error = hammer_reblock_data(reblock,
 224                                                             cursor, elm);
 225                         }
 226                         if (error == 0) {
 227                                 ++reblock->data_moves;
 228                                 reblock->data_byte_moves += elm->leaf.data_len;
 229                         }
 230                 }
 231         }
 232
 233 skip:
 234         /*
 235          * Reblock a B-Tree internal or leaf node.
 236          */
 237         tmp_offset = cursor->node->node_offset;
 238         if (cursor->index == 0 &&
 239             error == 0 && (reblock->head.flags & HAMMER_IOC_DO_BTREE)) {
 240                 ++reblock->btree_count;
 241                 bytes = hammer_blockmap_getfree(hmp, tmp_offset, &cur, &error);
 242                 if (hammer_debug_general & 0x4000)
 243                         kprintf("B %6d/%d\n", bytes, reblock->free_level);
 244                 if (error == 0 && (cur == 0 || reblock->free_level == 0) &&
 245                     bytes >= reblock->free_level) {
 246                         error = hammer_cursor_upgrade(cursor);
 247                         if (error == 0) {
 248                                 if (cursor->parent)
 249                                         elm = &cursor->parent->ondisk->elms[cursor->parent_index];
 250                                 else
 251                                         elm = NULL;
 252                                 switch(cursor->node->ondisk->type) {
 253                                 case HAMMER_BTREE_TYPE_LEAF:
 254                                         error = hammer_reblock_leaf_node(
 255                                                         reblock, cursor, elm);
 256                                         break;
 257                                 case HAMMER_BTREE_TYPE_INTERNAL:
 258                                         error = hammer_reblock_int_node(
 259                                                         reblock, cursor, elm);
 260                                         break;
 261                                 default:
 262                                         panic("Illegal B-Tree node type");
 263                                 }
 264                         }
 265                         if (error == 0) {
 266                                 ++reblock->btree_moves;
 267                         }
 268                 }
 269         }
 270
 271         hammer_cursor_downgrade(cursor);
 272         return(error);
 273 }
 274
 275 /*
 276  * Reblock a record's data.  Both the B-Tree element and record pointers
 277  * to the data must be adjusted.
 278  */
 279 static int
 280 hammer_reblock_data(struct hammer_ioc_reblock *reblock,
 281                     hammer_cursor_t cursor, hammer_btree_elm_t elm)
 282 {
 283         struct hammer_buffer *data_buffer = NULL;
 284         hammer_off_t ndata_offset;
 285         int error;
 286         void *ndata;
 287
 288         error = hammer_btree_extract(cursor, HAMMER_CURSOR_GET_DATA |
 289                                              HAMMER_CURSOR_GET_LEAF);
 290         if (error)
 291                 return (error);
 292         ndata = hammer_alloc_data(cursor->trans, elm->leaf.data_len,
 293                                   elm->leaf.base.rec_type,
 294                                   &ndata_offset, &data_buffer, &error);
 295         if (error)
 296                 goto done;
 297
 298         /*
 299          * Move the data
 300          */
 301         hammer_modify_buffer(cursor->trans, data_buffer, NULL, 0);
 302         bcopy(cursor->data, ndata, elm->leaf.data_len);
 303         hammer_modify_buffer_done(data_buffer);
 304
 305         hammer_blockmap_free(cursor->trans,
 306                              elm->leaf.data_offset, elm->leaf.data_len);
 307
 308         hammer_modify_node(cursor->trans, cursor->node,
 309                            &elm->leaf.data_offset, sizeof(hammer_off_t));
 310         elm->leaf.data_offset = ndata_offset;
 311         hammer_modify_node_done(cursor->node);
 312
 313 done:
 314         if (data_buffer)
 315                 hammer_rel_buffer(data_buffer, 0);
 316         return (error);
 317 }
 318
 319 /*
 320  * Reblock a B-Tree leaf node.  The parent must be adjusted to point to
 321  * the new copy of the leaf node.
 322  *
 323  * elm is a pointer to the parent element pointing at cursor.node.
 324  */
 325 static int
 326 hammer_reblock_leaf_node(struct hammer_ioc_reblock *reblock,
 327                          hammer_cursor_t cursor, hammer_btree_elm_t elm)
 328 {
 329         hammer_node_t onode;
 330         hammer_node_t nnode;
 331         int error;
 332
 333         onode = cursor->node;
 334         nnode = hammer_alloc_btree(cursor->trans, &error);
 335
 336         if (nnode == NULL)
 337                 return (error);
 338
 339         /*
 340          * Move the node
 341          */
 342         hammer_lock_ex(&nnode->lock);
 343         hammer_modify_node_noundo(cursor->trans, nnode);
 344         bcopy(onode->ondisk, nnode->ondisk, sizeof(*nnode->ondisk));
 345
 346         if (elm) {
 347                 /*
 348                  * We are not the root of the B-Tree
 349                  */
 350                 hammer_modify_node(cursor->trans, cursor->parent,
 351                                    &elm->internal.subtree_offset,
 352                                    sizeof(elm->internal.subtree_offset));
 353                 elm->internal.subtree_offset = nnode->node_offset;
 354                 hammer_modify_node_done(cursor->parent);
 355         } else {
 356                 /*
 357                  * We are the root of the B-Tree
 358                  */
 359                 hammer_volume_t volume;
 360
 361                 volume = hammer_get_root_volume(cursor->trans->hmp, &error);
 362                 KKASSERT(error == 0);
 363
 364                 hammer_modify_volume_field(cursor->trans, volume,
 365                                            vol0_btree_root);
 366                 volume->ondisk->vol0_btree_root = nnode->node_offset;
 367                 hammer_modify_volume_done(volume);
 368                 hammer_rel_volume(volume, 0);
 369         }
 370
 371         hammer_delete_node(cursor->trans, onode);
 372
 373         if (hammer_debug_general & 0x4000) {
 374                 kprintf("REBLOCK LNODE %016llx -> %016llx\n",
 375                         onode->node_offset, nnode->node_offset);
 376         }
 377         hammer_modify_node_done(nnode);
 378         cursor->node = nnode;
 379
 380         hammer_unlock(&onode->lock);
 381         hammer_rel_node(onode);
 382
 383         return (error);
 384 }
 385
 386 /*
 387  * Reblock a B-Tree internal node.  The parent must be adjusted to point to
 388  * the new copy of the internal node, and the node's children's parent
 389  * pointers must also be adjusted to point to the new copy.
 390  *
 391  * elm is a pointer to the parent element pointing at cursor.node.
 392  */
 393 static int
 394 hammer_reblock_int_node(struct hammer_ioc_reblock *reblock,
 395                          hammer_cursor_t cursor, hammer_btree_elm_t elm)
 396 {
 397         hammer_node_locklist_t locklist = NULL;
 398         hammer_node_t onode;
 399         hammer_node_t nnode;
 400         int error;
 401         int i;
 402
 403         error = hammer_btree_lock_children(cursor, &locklist);
 404         if (error)
 405                 goto done;
 406
 407         onode = cursor->node;
 408         nnode = hammer_alloc_btree(cursor->trans, &error);
 409
 410         if (nnode == NULL)
 411                 goto done;
 412
 413         /*
 414          * Move the node.  Adjust the parent's pointer to us first.
 415          */
 416         hammer_lock_ex(&nnode->lock);
 417         hammer_modify_node_noundo(cursor->trans, nnode);
 418         bcopy(onode->ondisk, nnode->ondisk, sizeof(*nnode->ondisk));
 419
 420         if (elm) {
 421                 /*
 422                  * We are not the root of the B-Tree
 423                  */
 424                 hammer_modify_node(cursor->trans, cursor->parent,
 425                                    &elm->internal.subtree_offset,
 426                                    sizeof(elm->internal.subtree_offset));
 427                 elm->internal.subtree_offset = nnode->node_offset;
 428                 hammer_modify_node_done(cursor->parent);
 429         } else {
 430                 /*
 431                  * We are the root of the B-Tree
 432                  */
 433                 hammer_volume_t volume;
 434
 435                 volume = hammer_get_root_volume(cursor->trans->hmp, &error);
 436                 KKASSERT(error == 0);
 437
 438                 hammer_modify_volume_field(cursor->trans, volume,
 439                                            vol0_btree_root);
 440                 volume->ondisk->vol0_btree_root = nnode->node_offset;
 441                 hammer_modify_volume_done(volume);
 442                 hammer_rel_volume(volume, 0);
 443         }
 444
 445         /*
 446          * Now adjust our children's pointers to us.
 447          */
 448         for (i = 0; i < nnode->ondisk->count; ++i) {
 449                 elm = &nnode->ondisk->elms[i];
 450                 error = btree_set_parent(cursor->trans, nnode, elm);
 451                 if (error)
 452                         panic("reblock internal node: fixup problem");
 453         }
 454
 455         /*
 456          * Clean up.
 457          *
 458          * The new node replaces the current node in the cursor.  The cursor
 459          * expects it to be locked so leave it locked.  Discard onode.
 460          */
 461         hammer_delete_node(cursor->trans, onode);
 462
 463         if (hammer_debug_general & 0x4000) {
 464                 kprintf("REBLOCK INODE %016llx -> %016llx\n",
 465                         onode->node_offset, nnode->node_offset);
 466         }
 467         hammer_modify_node_done(nnode);
 468         cursor->node = nnode;
 469
 470         hammer_unlock(&onode->lock);
 471         hammer_rel_node(onode);
 472
 473 done:
 474         hammer_btree_unlock_children(&locklist);
 475         return (error);
 476 }
 477