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 1.33 2008/07/16 18:30:59 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, 0); 153 hammer_flusher_wait(trans->hmp, seq); 154 hammer_lock_cursor(&cursor, 0); 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, 0); 172 hammer_flusher_wait(trans->hmp, seq); 173 hammer_lock_cursor(&cursor, 0); 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, 0); 193 bwillwrite(HAMMER_XBUFSIZE); 194 hammer_lock_cursor(&cursor, 0); 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 int error; 233 int bytes; 234 int cur; 235 int iocflags; 236 237 error = 0; 238 hmp = cursor->trans->hmp; 239 240 /* 241 * Reblock data. Note that data embedded in a record is reblocked 242 * by the record reblock code. Data processing only occurs at leaf 243 * nodes and for RECORD element types. 244 */ 245 if (cursor->node->ondisk->type != HAMMER_BTREE_TYPE_LEAF) 246 goto skip; 247 if (elm->leaf.base.btype != HAMMER_BTREE_TYPE_RECORD) 248 return(0); 249 tmp_offset = elm->leaf.data_offset; 250 if (tmp_offset == 0) 251 goto skip; 252 if (error) 253 goto skip; 254 255 /* 256 * NOTE: Localization restrictions may also have been set-up, we can't 257 * just set the match flags willy-nilly here. 258 */ 259 switch(elm->leaf.base.rec_type) { 260 case HAMMER_RECTYPE_INODE: 261 iocflags = HAMMER_IOC_DO_INODES; 262 break; 263 case HAMMER_RECTYPE_EXT: 264 case HAMMER_RECTYPE_FIX: 265 case HAMMER_RECTYPE_PFS: 266 case HAMMER_RECTYPE_DIRENTRY: 267 iocflags = HAMMER_IOC_DO_DIRS; 268 break; 269 case HAMMER_RECTYPE_DATA: 270 case HAMMER_RECTYPE_DB: 271 iocflags = HAMMER_IOC_DO_DATA; 272 break; 273 default: 274 iocflags = 0; 275 break; 276 } 277 if (reblock->head.flags & iocflags) { 278 ++reblock->data_count; 279 reblock->data_byte_count += elm->leaf.data_len; 280 bytes = hammer_blockmap_getfree(hmp, tmp_offset, &cur, &error); 281 if (hammer_debug_general & 0x4000) 282 kprintf("D %6d/%d\n", bytes, reblock->free_level); 283 if (error == 0 && (cur == 0 || reblock->free_level == 0) && 284 bytes >= reblock->free_level) { 285 hammer_io_direct_uncache(hmp, &elm->leaf); 286 error = hammer_cursor_upgrade(cursor); 287 if (error == 0) { 288 error = hammer_reblock_data(reblock, 289 cursor, elm); 290 } 291 if (error == 0) { 292 ++reblock->data_moves; 293 reblock->data_byte_moves += elm->leaf.data_len; 294 } 295 } 296 } 297 298 skip: 299 /* 300 * Reblock a B-Tree internal or leaf node. 301 */ 302 tmp_offset = cursor->node->node_offset; 303 if (cursor->index == 0 && 304 error == 0 && (reblock->head.flags & HAMMER_IOC_DO_BTREE)) { 305 ++reblock->btree_count; 306 bytes = hammer_blockmap_getfree(hmp, tmp_offset, &cur, &error); 307 if (hammer_debug_general & 0x4000) 308 kprintf("B %6d/%d\n", bytes, reblock->free_level); 309 if (error == 0 && (cur == 0 || reblock->free_level == 0) && 310 bytes >= reblock->free_level) { 311 error = hammer_cursor_upgrade(cursor); 312 if (error == 0) { 313 if (cursor->parent) 314 elm = &cursor->parent->ondisk->elms[cursor->parent_index]; 315 else 316 elm = NULL; 317 switch(cursor->node->ondisk->type) { 318 case HAMMER_BTREE_TYPE_LEAF: 319 error = hammer_reblock_leaf_node( 320 reblock, cursor, elm); 321 break; 322 case HAMMER_BTREE_TYPE_INTERNAL: 323 error = hammer_reblock_int_node( 324 reblock, cursor, elm); 325 break; 326 default: 327 panic("Illegal B-Tree node type"); 328 } 329 } 330 if (error == 0) { 331 ++reblock->btree_moves; 332 } 333 } 334 } 335 336 hammer_cursor_downgrade(cursor); 337 return(error); 338 } 339 340 /* 341 * Reblock a record's data. Both the B-Tree element and record pointers 342 * to the data must be adjusted. 343 */ 344 static int 345 hammer_reblock_data(struct hammer_ioc_reblock *reblock, 346 hammer_cursor_t cursor, hammer_btree_elm_t elm) 347 { 348 struct hammer_buffer *data_buffer = NULL; 349 hammer_off_t ndata_offset; 350 int error; 351 void *ndata; 352 353 error = hammer_btree_extract(cursor, HAMMER_CURSOR_GET_DATA | 354 HAMMER_CURSOR_GET_LEAF); 355 if (error) 356 return (error); 357 ndata = hammer_alloc_data(cursor->trans, elm->leaf.data_len, 358 elm->leaf.base.rec_type, 359 &ndata_offset, &data_buffer, &error); 360 if (error) 361 goto done; 362 363 /* 364 * Move the data 365 */ 366 hammer_modify_buffer(cursor->trans, data_buffer, NULL, 0); 367 bcopy(cursor->data, ndata, elm->leaf.data_len); 368 hammer_modify_buffer_done(data_buffer); 369 370 hammer_blockmap_free(cursor->trans, 371 elm->leaf.data_offset, elm->leaf.data_len); 372 373 hammer_modify_node(cursor->trans, cursor->node, 374 &elm->leaf.data_offset, sizeof(hammer_off_t)); 375 elm->leaf.data_offset = ndata_offset; 376 hammer_modify_node_done(cursor->node); 377 378 done: 379 if (data_buffer) 380 hammer_rel_buffer(data_buffer, 0); 381 return (error); 382 } 383 384 /* 385 * Reblock a B-Tree leaf node. The parent must be adjusted to point to 386 * the new copy of the leaf node. 387 * 388 * elm is a pointer to the parent element pointing at cursor.node. 389 */ 390 static int 391 hammer_reblock_leaf_node(struct hammer_ioc_reblock *reblock, 392 hammer_cursor_t cursor, hammer_btree_elm_t elm) 393 { 394 hammer_node_t onode; 395 hammer_node_t nnode; 396 int error; 397 398 onode = cursor->node; 399 nnode = hammer_alloc_btree(cursor->trans, &error); 400 401 if (nnode == NULL) 402 return (error); 403 404 /* 405 * Move the node 406 */ 407 hammer_lock_ex(&nnode->lock); 408 hammer_modify_node_noundo(cursor->trans, nnode); 409 bcopy(onode->ondisk, nnode->ondisk, sizeof(*nnode->ondisk)); 410 411 if (elm) { 412 /* 413 * We are not the root of the B-Tree 414 */ 415 hammer_modify_node(cursor->trans, cursor->parent, 416 &elm->internal.subtree_offset, 417 sizeof(elm->internal.subtree_offset)); 418 elm->internal.subtree_offset = nnode->node_offset; 419 hammer_modify_node_done(cursor->parent); 420 } else { 421 /* 422 * We are the root of the B-Tree 423 */ 424 hammer_volume_t volume; 425 426 volume = hammer_get_root_volume(cursor->trans->hmp, &error); 427 KKASSERT(error == 0); 428 429 hammer_modify_volume_field(cursor->trans, volume, 430 vol0_btree_root); 431 volume->ondisk->vol0_btree_root = nnode->node_offset; 432 hammer_modify_volume_done(volume); 433 hammer_rel_volume(volume, 0); 434 } 435 436 hammer_cursor_replaced_node(onode, nnode); 437 hammer_delete_node(cursor->trans, onode); 438 439 if (hammer_debug_general & 0x4000) { 440 kprintf("REBLOCK LNODE %016llx -> %016llx\n", 441 onode->node_offset, nnode->node_offset); 442 } 443 hammer_modify_node_done(nnode); 444 cursor->node = nnode; 445 446 hammer_unlock(&onode->lock); 447 hammer_rel_node(onode); 448 449 return (error); 450 } 451 452 /* 453 * Reblock a B-Tree internal node. The parent must be adjusted to point to 454 * the new copy of the internal node, and the node's children's parent 455 * pointers must also be adjusted to point to the new copy. 456 * 457 * elm is a pointer to the parent element pointing at cursor.node. 458 */ 459 static int 460 hammer_reblock_int_node(struct hammer_ioc_reblock *reblock, 461 hammer_cursor_t cursor, hammer_btree_elm_t elm) 462 { 463 hammer_node_locklist_t locklist = NULL; 464 hammer_node_t onode; 465 hammer_node_t nnode; 466 int error; 467 int i; 468 469 error = hammer_btree_lock_children(cursor, &locklist); 470 if (error) 471 goto done; 472 473 onode = cursor->node; 474 nnode = hammer_alloc_btree(cursor->trans, &error); 475 476 if (nnode == NULL) 477 goto done; 478 479 /* 480 * Move the node. Adjust the parent's pointer to us first. 481 */ 482 hammer_lock_ex(&nnode->lock); 483 hammer_modify_node_noundo(cursor->trans, nnode); 484 bcopy(onode->ondisk, nnode->ondisk, sizeof(*nnode->ondisk)); 485 486 if (elm) { 487 /* 488 * We are not the root of the B-Tree 489 */ 490 hammer_modify_node(cursor->trans, cursor->parent, 491 &elm->internal.subtree_offset, 492 sizeof(elm->internal.subtree_offset)); 493 elm->internal.subtree_offset = nnode->node_offset; 494 hammer_modify_node_done(cursor->parent); 495 } else { 496 /* 497 * We are the root of the B-Tree 498 */ 499 hammer_volume_t volume; 500 501 volume = hammer_get_root_volume(cursor->trans->hmp, &error); 502 KKASSERT(error == 0); 503 504 hammer_modify_volume_field(cursor->trans, volume, 505 vol0_btree_root); 506 volume->ondisk->vol0_btree_root = nnode->node_offset; 507 hammer_modify_volume_done(volume); 508 hammer_rel_volume(volume, 0); 509 } 510 511 /* 512 * Now adjust our children's pointers to us. 513 */ 514 for (i = 0; i < nnode->ondisk->count; ++i) { 515 elm = &nnode->ondisk->elms[i]; 516 error = btree_set_parent(cursor->trans, nnode, elm); 517 if (error) 518 panic("reblock internal node: fixup problem"); 519 } 520 521 /* 522 * Clean up. 523 * 524 * The new node replaces the current node in the cursor. The cursor 525 * expects it to be locked so leave it locked. Discard onode. 526 */ 527 hammer_cursor_replaced_node(onode, nnode); 528 hammer_delete_node(cursor->trans, onode); 529 530 if (hammer_debug_general & 0x4000) { 531 kprintf("REBLOCK INODE %016llx -> %016llx\n", 532 onode->node_offset, nnode->node_offset); 533 } 534 hammer_modify_node_done(nnode); 535 cursor->node = nnode; 536 537 hammer_unlock(&onode->lock); 538 hammer_rel_node(onode); 539 540 done: 541 hammer_btree_unlock_children(&locklist); 542 return (error); 543 } 544 545