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 1.34 2008/11/13 02:18:43 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 int slop; 68 69 /* 70 * A fill level <= 20% is considered an emergency. free_level is 71 * inverted from fill_level. 72 */ 73 if (reblock->free_level >= HAMMER_LARGEBLOCK_SIZE * 8 / 10) 74 slop = HAMMER_CHKSPC_EMERGENCY; 75 else 76 slop = HAMMER_CHKSPC_REBLOCK; 77 78 if ((reblock->key_beg.localization | reblock->key_end.localization) & 79 HAMMER_LOCALIZE_PSEUDOFS_MASK) { 80 return(EINVAL); 81 } 82 if (reblock->key_beg.obj_id >= reblock->key_end.obj_id) 83 return(EINVAL); 84 if (reblock->free_level < 0) 85 return(EINVAL); 86 87 reblock->key_cur = reblock->key_beg; 88 reblock->key_cur.localization &= HAMMER_LOCALIZE_MASK; 89 reblock->key_cur.localization += ip->obj_localization; 90 91 checkspace_count = 0; 92 seq = trans->hmp->flusher.act; 93 retry: 94 error = hammer_init_cursor(trans, &cursor, NULL, NULL); 95 if (error) { 96 hammer_done_cursor(&cursor); 97 goto failed; 98 } 99 cursor.key_beg.localization = reblock->key_cur.localization; 100 cursor.key_beg.obj_id = reblock->key_cur.obj_id; 101 cursor.key_beg.key = HAMMER_MIN_KEY; 102 cursor.key_beg.create_tid = 1; 103 cursor.key_beg.delete_tid = 0; 104 cursor.key_beg.rec_type = HAMMER_MIN_RECTYPE; 105 cursor.key_beg.obj_type = 0; 106 107 cursor.key_end.localization = (reblock->key_end.localization & 108 HAMMER_LOCALIZE_MASK) + 109 ip->obj_localization; 110 cursor.key_end.obj_id = reblock->key_end.obj_id; 111 cursor.key_end.key = HAMMER_MAX_KEY; 112 cursor.key_end.create_tid = HAMMER_MAX_TID - 1; 113 cursor.key_end.delete_tid = 0; 114 cursor.key_end.rec_type = HAMMER_MAX_RECTYPE; 115 cursor.key_end.obj_type = 0; 116 117 cursor.flags |= HAMMER_CURSOR_END_INCLUSIVE; 118 cursor.flags |= HAMMER_CURSOR_BACKEND; 119 120 /* 121 * This flag allows the btree scan code to return internal nodes, 122 * so we can reblock them in addition to the leafs. Only specify it 123 * if we intend to reblock B-Tree nodes. 124 */ 125 if (reblock->head.flags & HAMMER_IOC_DO_BTREE) 126 cursor.flags |= HAMMER_CURSOR_REBLOCKING; 127 128 error = hammer_btree_first(&cursor); 129 while (error == 0) { 130 /* 131 * Internal or Leaf node 132 */ 133 elm = &cursor.node->ondisk->elms[cursor.index]; 134 reblock->key_cur.obj_id = elm->base.obj_id; 135 reblock->key_cur.localization = elm->base.localization; 136 137 /* 138 * Yield to more important tasks 139 */ 140 if ((error = hammer_signal_check(trans->hmp)) != 0) 141 break; 142 143 /* 144 * If there is insufficient free space it may be due to 145 * reserved bigblocks, which flushing might fix. 146 */ 147 if (hammer_checkspace(trans->hmp, slop)) { 148 if (++checkspace_count == 10) { 149 error = ENOSPC; 150 break; 151 } 152 hammer_unlock_cursor(&cursor); 153 hammer_flusher_wait(trans->hmp, seq); 154 hammer_lock_cursor(&cursor); 155 seq = hammer_flusher_async(trans->hmp, NULL); 156 continue; 157 } 158 159 /* 160 * Acquiring the sync_lock prevents the operation from 161 * crossing a synchronization boundary. 162 * 163 * NOTE: cursor.node may have changed on return. 164 */ 165 hammer_sync_lock_sh(trans); 166 error = hammer_reblock_helper(reblock, &cursor, elm); 167 hammer_sync_unlock(trans); 168 169 while (hammer_flusher_meta_halflimit(trans->hmp) || 170 hammer_flusher_undo_exhausted(trans, 2)) { 171 hammer_unlock_cursor(&cursor); 172 hammer_flusher_wait(trans->hmp, seq); 173 hammer_lock_cursor(&cursor); 174 seq = hammer_flusher_async_one(trans->hmp); 175 } 176 177 /* 178 * Setup for iteration, our cursor flags may be modified by 179 * other threads while we are unlocked. 180 */ 181 cursor.flags |= HAMMER_CURSOR_ATEDISK; 182 183 /* 184 * We allocate data buffers, which atm we don't track 185 * dirty levels for because we allow the kernel to write 186 * them. But if we allocate too many we can still deadlock 187 * the buffer cache. 188 * 189 * (The cursor's node and element may change!) 190 */ 191 if (bd_heatup()) { 192 hammer_unlock_cursor(&cursor); 193 bwillwrite(HAMMER_XBUFSIZE); 194 hammer_lock_cursor(&cursor); 195 } 196 197 if (error == 0) { 198 error = hammer_btree_iterate(&cursor); 199 } 200 201 } 202 if (error == ENOENT) 203 error = 0; 204 hammer_done_cursor(&cursor); 205 if (error == EWOULDBLOCK) { 206 hammer_flusher_sync(trans->hmp); 207 goto retry; 208 } 209 if (error == EDEADLK) 210 goto retry; 211 if (error == EINTR) { 212 reblock->head.flags |= HAMMER_IOC_HEAD_INTR; 213 error = 0; 214 } 215 failed: 216 reblock->key_cur.localization &= HAMMER_LOCALIZE_MASK; 217 return(error); 218 } 219 220 /* 221 * Reblock the B-Tree (leaf) node, record, and/or data if necessary. 222 * 223 * XXX We have no visibility into internal B-Tree nodes at the moment, 224 * only leaf nodes. 225 */ 226 static int 227 hammer_reblock_helper(struct hammer_ioc_reblock *reblock, 228 hammer_cursor_t cursor, hammer_btree_elm_t elm) 229 { 230 hammer_mount_t hmp; 231 hammer_off_t tmp_offset; 232 struct hammer_btree_leaf_elm leaf; 233 int error; 234 int bytes; 235 int cur; 236 int iocflags; 237 238 error = 0; 239 hmp = cursor->trans->hmp; 240 241 /* 242 * Reblock data. Note that data embedded in a record is reblocked 243 * by the record reblock code. Data processing only occurs at leaf 244 * nodes and for RECORD element types. 245 */ 246 if (cursor->node->ondisk->type != HAMMER_BTREE_TYPE_LEAF) 247 goto skip; 248 if (elm->leaf.base.btype != HAMMER_BTREE_TYPE_RECORD) 249 return(0); 250 tmp_offset = elm->leaf.data_offset; 251 if (tmp_offset == 0) 252 goto skip; 253 if (error) 254 goto skip; 255 256 /* 257 * NOTE: Localization restrictions may also have been set-up, we can't 258 * just set the match flags willy-nilly here. 259 */ 260 switch(elm->leaf.base.rec_type) { 261 case HAMMER_RECTYPE_INODE: 262 iocflags = HAMMER_IOC_DO_INODES; 263 break; 264 case HAMMER_RECTYPE_EXT: 265 case HAMMER_RECTYPE_FIX: 266 case HAMMER_RECTYPE_PFS: 267 case HAMMER_RECTYPE_DIRENTRY: 268 iocflags = HAMMER_IOC_DO_DIRS; 269 break; 270 case HAMMER_RECTYPE_DATA: 271 case HAMMER_RECTYPE_DB: 272 iocflags = HAMMER_IOC_DO_DATA; 273 break; 274 default: 275 iocflags = 0; 276 break; 277 } 278 if (reblock->head.flags & iocflags) { 279 ++reblock->data_count; 280 reblock->data_byte_count += elm->leaf.data_len; 281 bytes = hammer_blockmap_getfree(hmp, tmp_offset, &cur, &error); 282 if (hammer_debug_general & 0x4000) 283 kprintf("D %6d/%d\n", bytes, reblock->free_level); 284 if (error == 0 && (cur == 0 || reblock->free_level == 0) && 285 bytes >= reblock->free_level) { 286 /* 287 * This is nasty, the uncache code may have to get 288 * vnode locks and because of that we can't hold 289 * the cursor locked. 290 */ 291 leaf = elm->leaf; 292 hammer_unlock_cursor(cursor); 293 hammer_io_direct_uncache(hmp, &leaf); 294 hammer_lock_cursor(cursor); 295 if (cursor->flags & HAMMER_CURSOR_RETEST) { 296 kprintf("hammer: retest after uncache\n"); 297 error = EDEADLK; 298 } else { 299 KKASSERT(bcmp(&elm->leaf, &leaf, sizeof(leaf)) == 0); 300 } 301 if (error == 0) 302 error = hammer_cursor_upgrade(cursor); 303 if (error == 0) { 304 error = hammer_reblock_data(reblock, 305 cursor, elm); 306 } 307 if (error == 0) { 308 ++reblock->data_moves; 309 reblock->data_byte_moves += elm->leaf.data_len; 310 } 311 } 312 } 313 314 skip: 315 /* 316 * Reblock a B-Tree internal or leaf node. A leaf node is reblocked 317 * on initial entry only (element 0). An internal node is reblocked 318 * when entered upward from its first leaf node only (also element 0). 319 * Further revisits of the internal node (index > 0) are ignored. 320 */ 321 tmp_offset = cursor->node->node_offset; 322 if (cursor->index == 0 && 323 error == 0 && (reblock->head.flags & HAMMER_IOC_DO_BTREE)) { 324 ++reblock->btree_count; 325 bytes = hammer_blockmap_getfree(hmp, tmp_offset, &cur, &error); 326 if (hammer_debug_general & 0x4000) 327 kprintf("B %6d/%d\n", bytes, reblock->free_level); 328 if (error == 0 && (cur == 0 || reblock->free_level == 0) && 329 bytes >= reblock->free_level) { 330 error = hammer_cursor_upgrade(cursor); 331 if (error == 0) { 332 if (cursor->parent) 333 elm = &cursor->parent->ondisk->elms[cursor->parent_index]; 334 else 335 elm = NULL; 336 switch(cursor->node->ondisk->type) { 337 case HAMMER_BTREE_TYPE_LEAF: 338 error = hammer_reblock_leaf_node( 339 reblock, cursor, elm); 340 break; 341 case HAMMER_BTREE_TYPE_INTERNAL: 342 error = hammer_reblock_int_node( 343 reblock, cursor, elm); 344 break; 345 default: 346 panic("Illegal B-Tree node type"); 347 } 348 } 349 if (error == 0) { 350 ++reblock->btree_moves; 351 } 352 } 353 } 354 355 hammer_cursor_downgrade(cursor); 356 return(error); 357 } 358 359 /* 360 * Reblock a record's data. Both the B-Tree element and record pointers 361 * to the data must be adjusted. 362 */ 363 static int 364 hammer_reblock_data(struct hammer_ioc_reblock *reblock, 365 hammer_cursor_t cursor, hammer_btree_elm_t elm) 366 { 367 struct hammer_buffer *data_buffer = NULL; 368 hammer_off_t ndata_offset; 369 int error; 370 void *ndata; 371 372 error = hammer_btree_extract(cursor, HAMMER_CURSOR_GET_DATA | 373 HAMMER_CURSOR_GET_LEAF); 374 if (error) 375 return (error); 376 ndata = hammer_alloc_data(cursor->trans, elm->leaf.data_len, 377 elm->leaf.base.rec_type, 378 &ndata_offset, &data_buffer, &error); 379 if (error) 380 goto done; 381 382 /* 383 * Move the data 384 */ 385 hammer_modify_buffer(cursor->trans, data_buffer, NULL, 0); 386 bcopy(cursor->data, ndata, elm->leaf.data_len); 387 hammer_modify_buffer_done(data_buffer); 388 389 hammer_blockmap_free(cursor->trans, 390 elm->leaf.data_offset, elm->leaf.data_len); 391 392 hammer_modify_node(cursor->trans, cursor->node, 393 &elm->leaf.data_offset, sizeof(hammer_off_t)); 394 elm->leaf.data_offset = ndata_offset; 395 hammer_modify_node_done(cursor->node); 396 397 done: 398 if (data_buffer) 399 hammer_rel_buffer(data_buffer, 0); 400 return (error); 401 } 402 403 /* 404 * Reblock a B-Tree leaf node. The parent must be adjusted to point to 405 * the new copy of the leaf node. 406 * 407 * elm is a pointer to the parent element pointing at cursor.node. 408 */ 409 static int 410 hammer_reblock_leaf_node(struct hammer_ioc_reblock *reblock, 411 hammer_cursor_t cursor, hammer_btree_elm_t elm) 412 { 413 hammer_node_t onode; 414 hammer_node_t nnode; 415 int error; 416 417 onode = cursor->node; 418 nnode = hammer_alloc_btree(cursor->trans, &error); 419 420 if (nnode == NULL) 421 return (error); 422 423 /* 424 * Move the node 425 */ 426 hammer_lock_ex(&nnode->lock); 427 hammer_modify_node_noundo(cursor->trans, nnode); 428 bcopy(onode->ondisk, nnode->ondisk, sizeof(*nnode->ondisk)); 429 430 if (elm) { 431 /* 432 * We are not the root of the B-Tree 433 */ 434 hammer_modify_node(cursor->trans, cursor->parent, 435 &elm->internal.subtree_offset, 436 sizeof(elm->internal.subtree_offset)); 437 elm->internal.subtree_offset = nnode->node_offset; 438 hammer_modify_node_done(cursor->parent); 439 } else { 440 /* 441 * We are the root of the B-Tree 442 */ 443 hammer_volume_t volume; 444 445 volume = hammer_get_root_volume(cursor->trans->hmp, &error); 446 KKASSERT(error == 0); 447 448 hammer_modify_volume_field(cursor->trans, volume, 449 vol0_btree_root); 450 volume->ondisk->vol0_btree_root = nnode->node_offset; 451 hammer_modify_volume_done(volume); 452 hammer_rel_volume(volume, 0); 453 } 454 455 hammer_cursor_replaced_node(onode, nnode); 456 hammer_delete_node(cursor->trans, onode); 457 458 if (hammer_debug_general & 0x4000) { 459 kprintf("REBLOCK LNODE %016llx -> %016llx\n", 460 onode->node_offset, nnode->node_offset); 461 } 462 hammer_modify_node_done(nnode); 463 cursor->node = nnode; 464 465 hammer_unlock(&onode->lock); 466 hammer_rel_node(onode); 467 468 return (error); 469 } 470 471 /* 472 * Reblock a B-Tree internal node. The parent must be adjusted to point to 473 * the new copy of the internal node, and the node's children's parent 474 * pointers must also be adjusted to point to the new copy. 475 * 476 * elm is a pointer to the parent element pointing at cursor.node. 477 */ 478 static int 479 hammer_reblock_int_node(struct hammer_ioc_reblock *reblock, 480 hammer_cursor_t cursor, hammer_btree_elm_t elm) 481 { 482 struct hammer_node_lock lockroot; 483 hammer_node_t onode; 484 hammer_node_t nnode; 485 int error; 486 int i; 487 488 hammer_node_lock_init(&lockroot, cursor->node); 489 error = hammer_btree_lock_children(cursor, 1, &lockroot); 490 if (error) 491 goto done; 492 493 onode = cursor->node; 494 nnode = hammer_alloc_btree(cursor->trans, &error); 495 496 if (nnode == NULL) 497 goto done; 498 499 /* 500 * Move the node. Adjust the parent's pointer to us first. 501 */ 502 hammer_lock_ex(&nnode->lock); 503 hammer_modify_node_noundo(cursor->trans, nnode); 504 bcopy(onode->ondisk, nnode->ondisk, sizeof(*nnode->ondisk)); 505 506 if (elm) { 507 /* 508 * We are not the root of the B-Tree 509 */ 510 hammer_modify_node(cursor->trans, cursor->parent, 511 &elm->internal.subtree_offset, 512 sizeof(elm->internal.subtree_offset)); 513 elm->internal.subtree_offset = nnode->node_offset; 514 hammer_modify_node_done(cursor->parent); 515 } else { 516 /* 517 * We are the root of the B-Tree 518 */ 519 hammer_volume_t volume; 520 521 volume = hammer_get_root_volume(cursor->trans->hmp, &error); 522 KKASSERT(error == 0); 523 524 hammer_modify_volume_field(cursor->trans, volume, 525 vol0_btree_root); 526 volume->ondisk->vol0_btree_root = nnode->node_offset; 527 hammer_modify_volume_done(volume); 528 hammer_rel_volume(volume, 0); 529 } 530 531 /* 532 * Now adjust our children's pointers to us. 533 */ 534 for (i = 0; i < nnode->ondisk->count; ++i) { 535 elm = &nnode->ondisk->elms[i]; 536 error = btree_set_parent(cursor->trans, nnode, elm); 537 if (error) 538 panic("reblock internal node: fixup problem"); 539 } 540 541 /* 542 * Clean up. 543 * 544 * The new node replaces the current node in the cursor. The cursor 545 * expects it to be locked so leave it locked. Discard onode. 546 */ 547 hammer_cursor_replaced_node(onode, nnode); 548 hammer_delete_node(cursor->trans, onode); 549 550 if (hammer_debug_general & 0x4000) { 551 kprintf("REBLOCK INODE %016llx -> %016llx\n", 552 onode->node_offset, nnode->node_offset); 553 } 554 hammer_modify_node_done(nnode); 555 cursor->node = nnode; 556 557 hammer_unlock(&onode->lock); 558 hammer_rel_node(onode); 559 560 done: 561 hammer_btree_unlock_children(cursor, &lockroot); 562 return (error); 563 } 564 565