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 1.28 2008/07/12 02:47:39 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 checkspace_count;
  65         int error;
  66         int seq;
  67
  68         if ((reblock->key_beg.localization | reblock->key_end.localization) &
  69             HAMMER_LOCALIZE_PSEUDOFS_MASK) {
  70                 return(EINVAL);
  71         }
  72         if (reblock->key_beg.obj_id >= reblock->key_end.obj_id)
  73                 return(EINVAL);
  74         if (reblock->free_level < 0)
  75                 return(EINVAL);
  76
  77         reblock->key_cur = reblock->key_beg;
  78         reblock->key_cur.localization &= HAMMER_LOCALIZE_MASK;
  79         reblock->key_cur.localization += ip->obj_localization;
  80
  81         checkspace_count = 0;
  82         seq = trans->hmp->flusher.act;
  83 retry:
  84         error = hammer_init_cursor(trans, &cursor, NULL, NULL);
  85         if (error) {
  86                 hammer_done_cursor(&cursor);
  87                 goto failed;
  88         }
  89         cursor.key_beg.localization = reblock->key_cur.localization;
  90         cursor.key_beg.obj_id = reblock->key_cur.obj_id;
  91         cursor.key_beg.key = HAMMER_MIN_KEY;
  92         cursor.key_beg.create_tid = 1;
  93         cursor.key_beg.delete_tid = 0;
  94         cursor.key_beg.rec_type = HAMMER_MIN_RECTYPE;
  95         cursor.key_beg.obj_type = 0;
  96
  97         cursor.key_end.localization = (reblock->key_end.localization &
  98                                         HAMMER_LOCALIZE_MASK) +
  99                                       ip->obj_localization;
 100         cursor.key_end.obj_id = reblock->key_end.obj_id;
 101         cursor.key_end.key = HAMMER_MAX_KEY;
 102         cursor.key_end.create_tid = HAMMER_MAX_TID - 1;
 103         cursor.key_end.delete_tid = 0;
 104         cursor.key_end.rec_type = HAMMER_MAX_RECTYPE;
 105         cursor.key_end.obj_type = 0;
 106
 107         cursor.flags |= HAMMER_CURSOR_END_INCLUSIVE;
 108         cursor.flags |= HAMMER_CURSOR_BACKEND;
 109
 110         /*
 111          * This flag allows the btree scan code to return internal nodes,
 112          * so we can reblock them in addition to the leafs.  Only specify it
 113          * if we intend to reblock B-Tree nodes.
 114          */
 115         if (reblock->head.flags & HAMMER_IOC_DO_BTREE)
 116                 cursor.flags |= HAMMER_CURSOR_REBLOCKING;
 117
 118         error = hammer_btree_first(&cursor);
 119         while (error == 0) {
 120                 /*
 121                  * Internal or Leaf node
 122                  */
 123                 elm = &cursor.node->ondisk->elms[cursor.index];
 124                 reblock->key_cur.obj_id = elm->base.obj_id;
 125                 reblock->key_cur.localization = elm->base.localization;
 126
 127                 /*
 128                  * Yield to more important tasks
 129                  */
 130                 if ((error = hammer_signal_check(trans->hmp)) != 0)
 131                         break;
 132
 133                 /*
 134                  * If there is insufficient free space it may be due to
 135                  * reserved bigblocks, which flushing might fix.
 136                  */
 137                 if (hammer_checkspace(trans->hmp, HAMMER_CHKSPC_REBLOCK)) {
 138                         if (++checkspace_count == 10) {
 139                                 error = ENOSPC;
 140                                 break;
 141                         }
 142                         hammer_unlock_cursor(&cursor, 0);
 143                         hammer_flusher_wait(trans->hmp, seq);
 144                         hammer_lock_cursor(&cursor, 0);
 145                         seq = hammer_flusher_async(trans->hmp);
 146                 }
 147
 148                 /*
 149                  * Acquiring the sync_lock prevents the operation from
 150                  * crossing a synchronization boundary.
 151                  *
 152                  * NOTE: cursor.node may have changed on return.
 153                  */
 154                 hammer_sync_lock_sh(trans);
 155                 error = hammer_reblock_helper(reblock, &cursor, elm);
 156                 hammer_sync_unlock(trans);
 157
 158                 if (hammer_flusher_meta_halflimit(trans->hmp) ||
 159                     hammer_flusher_undo_exhausted(trans, 1)) {
 160                         hammer_unlock_cursor(&cursor, 0);
 161                         hammer_flusher_wait(trans->hmp, seq);
 162                         hammer_lock_cursor(&cursor, 0);
 163                         seq = hammer_flusher_async(trans->hmp);
 164                 }
 165                 if (error == 0) {
 166                         cursor.flags |= HAMMER_CURSOR_ATEDISK;
 167                         error = hammer_btree_iterate(&cursor);
 168                 }
 169
 170         }
 171         if (error == ENOENT)
 172                 error = 0;
 173         hammer_done_cursor(&cursor);
 174         if (error == EWOULDBLOCK) {
 175                 hammer_flusher_sync(trans->hmp);
 176                 goto retry;
 177         }
 178         if (error == EDEADLK)
 179                 goto retry;
 180         if (error == EINTR) {
 181                 reblock->head.flags |= HAMMER_IOC_HEAD_INTR;
 182                 error = 0;
 183         }
 184 failed:
 185         reblock->key_cur.localization &= HAMMER_LOCALIZE_MASK;
 186         return(error);
 187 }
 188
 189 /*
 190  * Reblock the B-Tree (leaf) node, record, and/or data if necessary.
 191  *
 192  * XXX We have no visibility into internal B-Tree nodes at the moment,
 193  * only leaf nodes.
 194  */
 195 static int
 196 hammer_reblock_helper(struct hammer_ioc_reblock *reblock,
 197                       hammer_cursor_t cursor, hammer_btree_elm_t elm)
 198 {
 199         hammer_mount_t hmp;
 200         hammer_off_t tmp_offset;
 201         int error;
 202         int bytes;
 203         int cur;
 204         int iocflags;
 205
 206         error = 0;
 207         hmp = cursor->trans->hmp;
 208
 209         /*
 210          * Reblock data.  Note that data embedded in a record is reblocked
 211          * by the record reblock code.  Data processing only occurs at leaf
 212          * nodes and for RECORD element types.
 213          */
 214         if (cursor->node->ondisk->type != HAMMER_BTREE_TYPE_LEAF)
 215                 goto skip;
 216         if (elm->leaf.base.btype != HAMMER_BTREE_TYPE_RECORD)
 217                 return(0);
 218         tmp_offset = elm->leaf.data_offset;
 219         if (tmp_offset == 0)
 220                 goto skip;
 221         if (error)
 222                 goto skip;
 223
 224         /*
 225          * NOTE: Localization restrictions may also have been set-up, we can't
 226          * just set the match flags willy-nilly here.
 227          */
 228         switch(elm->leaf.base.rec_type) {
 229         case HAMMER_RECTYPE_INODE:
 230                 iocflags = HAMMER_IOC_DO_INODES;
 231                 break;
 232         case HAMMER_RECTYPE_EXT:
 233         case HAMMER_RECTYPE_FIX:
 234         case HAMMER_RECTYPE_PFS:
 235         case HAMMER_RECTYPE_DIRENTRY:
 236                 iocflags = HAMMER_IOC_DO_DIRS;
 237                 break;
 238         case HAMMER_RECTYPE_DATA:
 239         case HAMMER_RECTYPE_DB:
 240                 iocflags = HAMMER_IOC_DO_DATA;
 241                 break;
 242         default:
 243                 iocflags = 0;
 244                 break;
 245         }
 246         if (reblock->head.flags & iocflags) {
 247                 ++reblock->data_count;
 248                 reblock->data_byte_count += elm->leaf.data_len;
 249                 bytes = hammer_blockmap_getfree(hmp, tmp_offset, &cur, &error);
 250                 if (hammer_debug_general & 0x4000)
 251                         kprintf("D %6d/%d\n", bytes, reblock->free_level);
 252                 if (error == 0 && (cur == 0 || reblock->free_level == 0) &&
 253                     bytes >= reblock->free_level) {
 254                         hammer_io_direct_uncache(hmp, &elm->leaf);
 255                         error = hammer_cursor_upgrade(cursor);
 256                         if (error == 0) {
 257                                 error = hammer_reblock_data(reblock,
 258                                                             cursor, elm);
 259                         }
 260                         if (error == 0) {
 261                                 ++reblock->data_moves;
 262                                 reblock->data_byte_moves += elm->leaf.data_len;
 263                         }
 264                 }
 265         }
 266
 267 skip:
 268         /*
 269          * Reblock a B-Tree internal or leaf node.
 270          */
 271         tmp_offset = cursor->node->node_offset;
 272         if (cursor->index == 0 &&
 273             error == 0 && (reblock->head.flags & HAMMER_IOC_DO_BTREE)) {
 274                 ++reblock->btree_count;
 275                 bytes = hammer_blockmap_getfree(hmp, tmp_offset, &cur, &error);
 276                 if (hammer_debug_general & 0x4000)
 277                         kprintf("B %6d/%d\n", bytes, reblock->free_level);
 278                 if (error == 0 && (cur == 0 || reblock->free_level == 0) &&
 279                     bytes >= reblock->free_level) {
 280                         error = hammer_cursor_upgrade(cursor);
 281                         if (error == 0) {
 282                                 if (cursor->parent)
 283                                         elm = &cursor->parent->ondisk->elms[cursor->parent_index];
 284                                 else
 285                                         elm = NULL;
 286                                 switch(cursor->node->ondisk->type) {
 287                                 case HAMMER_BTREE_TYPE_LEAF:
 288                                         error = hammer_reblock_leaf_node(
 289                                                         reblock, cursor, elm);
 290                                         break;
 291                                 case HAMMER_BTREE_TYPE_INTERNAL:
 292                                         error = hammer_reblock_int_node(
 293                                                         reblock, cursor, elm);
 294                                         break;
 295                                 default:
 296                                         panic("Illegal B-Tree node type");
 297                                 }
 298                         }
 299                         if (error == 0) {
 300                                 ++reblock->btree_moves;
 301                         }
 302                 }
 303         }
 304
 305         hammer_cursor_downgrade(cursor);
 306         return(error);
 307 }
 308
 309 /*
 310  * Reblock a record's data.  Both the B-Tree element and record pointers
 311  * to the data must be adjusted.
 312  */
 313 static int
 314 hammer_reblock_data(struct hammer_ioc_reblock *reblock,
 315                     hammer_cursor_t cursor, hammer_btree_elm_t elm)
 316 {
 317         struct hammer_buffer *data_buffer = NULL;
 318         hammer_off_t ndata_offset;
 319         int error;
 320         void *ndata;
 321
 322         error = hammer_btree_extract(cursor, HAMMER_CURSOR_GET_DATA |
 323                                              HAMMER_CURSOR_GET_LEAF);
 324         if (error)
 325                 return (error);
 326         ndata = hammer_alloc_data(cursor->trans, elm->leaf.data_len,
 327                                   elm->leaf.base.rec_type,
 328                                   &ndata_offset, &data_buffer, &error);
 329         if (error)
 330                 goto done;
 331
 332         /*
 333          * Move the data
 334          */
 335         hammer_modify_buffer(cursor->trans, data_buffer, NULL, 0);
 336         bcopy(cursor->data, ndata, elm->leaf.data_len);
 337         hammer_modify_buffer_done(data_buffer);
 338
 339         hammer_blockmap_free(cursor->trans,
 340                              elm->leaf.data_offset, elm->leaf.data_len);
 341
 342         hammer_modify_node(cursor->trans, cursor->node,
 343                            &elm->leaf.data_offset, sizeof(hammer_off_t));
 344         elm->leaf.data_offset = ndata_offset;
 345         hammer_modify_node_done(cursor->node);
 346
 347 done:
 348         if (data_buffer)
 349                 hammer_rel_buffer(data_buffer, 0);
 350         return (error);
 351 }
 352
 353 /*
 354  * Reblock a B-Tree leaf node.  The parent must be adjusted to point to
 355  * the new copy of the leaf node.
 356  *
 357  * elm is a pointer to the parent element pointing at cursor.node.
 358  */
 359 static int
 360 hammer_reblock_leaf_node(struct hammer_ioc_reblock *reblock,
 361                          hammer_cursor_t cursor, hammer_btree_elm_t elm)
 362 {
 363         hammer_node_t onode;
 364         hammer_node_t nnode;
 365         int error;
 366
 367         onode = cursor->node;
 368         nnode = hammer_alloc_btree(cursor->trans, &error);
 369
 370         if (nnode == NULL)
 371                 return (error);
 372
 373         /*
 374          * Move the node
 375          */
 376         hammer_lock_ex(&nnode->lock);
 377         hammer_modify_node_noundo(cursor->trans, nnode);
 378         bcopy(onode->ondisk, nnode->ondisk, sizeof(*nnode->ondisk));
 379
 380         if (elm) {
 381                 /*
 382                  * We are not the root of the B-Tree
 383                  */
 384                 hammer_modify_node(cursor->trans, cursor->parent,
 385                                    &elm->internal.subtree_offset,
 386                                    sizeof(elm->internal.subtree_offset));
 387                 elm->internal.subtree_offset = nnode->node_offset;
 388                 hammer_modify_node_done(cursor->parent);
 389         } else {
 390                 /*
 391                  * We are the root of the B-Tree
 392                  */
 393                 hammer_volume_t volume;
 394
 395                 volume = hammer_get_root_volume(cursor->trans->hmp, &error);
 396                 KKASSERT(error == 0);
 397
 398                 hammer_modify_volume_field(cursor->trans, volume,
 399                                            vol0_btree_root);
 400                 volume->ondisk->vol0_btree_root = nnode->node_offset;
 401                 hammer_modify_volume_done(volume);
 402                 hammer_rel_volume(volume, 0);
 403         }
 404
 405         hammer_cursor_replaced_node(onode, nnode);
 406         hammer_delete_node(cursor->trans, onode);
 407
 408         if (hammer_debug_general & 0x4000) {
 409                 kprintf("REBLOCK LNODE %016llx -> %016llx\n",
 410                         onode->node_offset, nnode->node_offset);
 411         }
 412         hammer_modify_node_done(nnode);
 413         cursor->node = nnode;
 414
 415         hammer_unlock(&onode->lock);
 416         hammer_rel_node(onode);
 417
 418         return (error);
 419 }
 420
 421 /*
 422  * Reblock a B-Tree internal node.  The parent must be adjusted to point to
 423  * the new copy of the internal node, and the node's children's parent
 424  * pointers must also be adjusted to point to the new copy.
 425  *
 426  * elm is a pointer to the parent element pointing at cursor.node.
 427  */
 428 static int
 429 hammer_reblock_int_node(struct hammer_ioc_reblock *reblock,
 430                          hammer_cursor_t cursor, hammer_btree_elm_t elm)
 431 {
 432         hammer_node_locklist_t locklist = NULL;
 433         hammer_node_t onode;
 434         hammer_node_t nnode;
 435         int error;
 436         int i;
 437
 438         error = hammer_btree_lock_children(cursor, &locklist);
 439         if (error)
 440                 goto done;
 441
 442         onode = cursor->node;
 443         nnode = hammer_alloc_btree(cursor->trans, &error);
 444
 445         if (nnode == NULL)
 446                 goto done;
 447
 448         /*
 449          * Move the node.  Adjust the parent's pointer to us first.
 450          */
 451         hammer_lock_ex(&nnode->lock);
 452         hammer_modify_node_noundo(cursor->trans, nnode);
 453         bcopy(onode->ondisk, nnode->ondisk, sizeof(*nnode->ondisk));
 454
 455         if (elm) {
 456                 /*
 457                  * We are not the root of the B-Tree
 458                  */
 459                 hammer_modify_node(cursor->trans, cursor->parent,
 460                                    &elm->internal.subtree_offset,
 461                                    sizeof(elm->internal.subtree_offset));
 462                 elm->internal.subtree_offset = nnode->node_offset;
 463                 hammer_modify_node_done(cursor->parent);
 464         } else {
 465                 /*
 466                  * We are the root of the B-Tree
 467                  */
 468                 hammer_volume_t volume;
 469
 470                 volume = hammer_get_root_volume(cursor->trans->hmp, &error);
 471                 KKASSERT(error == 0);
 472
 473                 hammer_modify_volume_field(cursor->trans, volume,
 474                                            vol0_btree_root);
 475                 volume->ondisk->vol0_btree_root = nnode->node_offset;
 476                 hammer_modify_volume_done(volume);
 477                 hammer_rel_volume(volume, 0);
 478         }
 479
 480         /*
 481          * Now adjust our children's pointers to us.
 482          */
 483         for (i = 0; i < nnode->ondisk->count; ++i) {
 484                 elm = &nnode->ondisk->elms[i];
 485                 error = btree_set_parent(cursor->trans, nnode, elm);
 486                 if (error)
 487                         panic("reblock internal node: fixup problem");
 488         }
 489
 490         /*
 491          * Clean up.
 492          *
 493          * The new node replaces the current node in the cursor.  The cursor
 494          * expects it to be locked so leave it locked.  Discard onode.
 495          */
 496         hammer_cursor_replaced_node(onode, nnode);
 497         hammer_delete_node(cursor->trans, onode);
 498
 499         if (hammer_debug_general & 0x4000) {
 500                 kprintf("REBLOCK INODE %016llx -> %016llx\n",
 501                         onode->node_offset, nnode->node_offset);
 502         }
 503         hammer_modify_node_done(nnode);
 504         cursor->node = nnode;
 505
 506         hammer_unlock(&onode->lock);
 507         hammer_rel_node(onode);
 508
 509 done:
 510         hammer_btree_unlock_children(&locklist);
 511         return (error);
 512 }
 513