1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 /* 22 * Copyright 2008 Sun Microsystems, Inc. All rights reserved. 23 * Use is subject to license terms. 24 */ 25 26 #include <sys/zfs_context.h> 27 #include <sys/spa.h> 28 #include <sys/dmu.h> 29 #include <sys/zio.h> 30 #include <sys/space_map.h> 31 32 /* 33 * Space map routines. 34 * NOTE: caller is responsible for all locking. 35 */ 36 static int 37 space_map_seg_compare(const void *x1, const void *x2) 38 { 39 const space_seg_t *s1 = x1; 40 const space_seg_t *s2 = x2; 41 42 if (s1->ss_start < s2->ss_start) { 43 if (s1->ss_end > s2->ss_start) 44 return (0); 45 return (-1); 46 } 47 if (s1->ss_start > s2->ss_start) { 48 if (s1->ss_start < s2->ss_end) 49 return (0); 50 return (1); 51 } 52 return (0); 53 } 54 55 void 56 space_map_create(space_map_t *sm, uint64_t start, uint64_t size, uint8_t shift, 57 kmutex_t *lp) 58 { 59 bzero(sm, sizeof (*sm)); 60 61 cv_init(&sm->sm_load_cv, NULL, CV_DEFAULT, NULL); 62 63 avl_create(&sm->sm_root, space_map_seg_compare, 64 sizeof (space_seg_t), offsetof(struct space_seg, ss_node)); 65 66 sm->sm_start = start; 67 sm->sm_size = size; 68 sm->sm_shift = shift; 69 sm->sm_lock = lp; 70 } 71 72 void 73 space_map_destroy(space_map_t *sm) 74 { 75 ASSERT(!sm->sm_loaded && !sm->sm_loading); 76 VERIFY3U(sm->sm_space, ==, 0); 77 avl_destroy(&sm->sm_root); 78 cv_destroy(&sm->sm_load_cv); 79 } 80 81 void 82 space_map_add(space_map_t *sm, uint64_t start, uint64_t size) 83 { 84 avl_index_t where; 85 space_seg_t ssearch, *ss_before, *ss_after, *ss; 86 uint64_t end = start + size; 87 int merge_before, merge_after; 88 89 ASSERT(MUTEX_HELD(sm->sm_lock)); 90 VERIFY(size != 0); 91 VERIFY3U(start, >=, sm->sm_start); 92 VERIFY3U(end, <=, sm->sm_start + sm->sm_size); 93 VERIFY(sm->sm_space + size <= sm->sm_size); 94 VERIFY(P2PHASE(start, 1ULL << sm->sm_shift) == 0); 95 VERIFY(P2PHASE(size, 1ULL << sm->sm_shift) == 0); 96 97 ssearch.ss_start = start; 98 ssearch.ss_end = end; 99 ss = avl_find(&sm->sm_root, &ssearch, &where); 100 101 if (ss != NULL && ss->ss_start <= start && ss->ss_end >= end) { 102 zfs_panic_recover("zfs: allocating allocated segment" 103 "(offset=%llu size=%llu)\n", 104 (longlong_t)start, (longlong_t)size); 105 return; 106 } 107 108 /* Make sure we don't overlap with either of our neighbors */ 109 VERIFY(ss == NULL); 110 111 ss_before = avl_nearest(&sm->sm_root, where, AVL_BEFORE); 112 ss_after = avl_nearest(&sm->sm_root, where, AVL_AFTER); 113 114 merge_before = (ss_before != NULL && ss_before->ss_end == start); 115 merge_after = (ss_after != NULL && ss_after->ss_start == end); 116 117 if (merge_before && merge_after) { 118 avl_remove(&sm->sm_root, ss_before); 119 ss_after->ss_start = ss_before->ss_start; 120 kmem_free(ss_before, sizeof (*ss_before)); 121 } else if (merge_before) { 122 ss_before->ss_end = end; 123 } else if (merge_after) { 124 ss_after->ss_start = start; 125 } else { 126 ss = kmem_alloc(sizeof (*ss), KM_SLEEP); 127 ss->ss_start = start; 128 ss->ss_end = end; 129 avl_insert(&sm->sm_root, ss, where); 130 } 131 132 sm->sm_space += size; 133 } 134 135 void 136 space_map_remove(space_map_t *sm, uint64_t start, uint64_t size) 137 { 138 avl_index_t where; 139 space_seg_t ssearch, *ss, *newseg; 140 uint64_t end = start + size; 141 int left_over, right_over; 142 143 ASSERT(MUTEX_HELD(sm->sm_lock)); 144 VERIFY(size != 0); 145 VERIFY(P2PHASE(start, 1ULL << sm->sm_shift) == 0); 146 VERIFY(P2PHASE(size, 1ULL << sm->sm_shift) == 0); 147 148 ssearch.ss_start = start; 149 ssearch.ss_end = end; 150 ss = avl_find(&sm->sm_root, &ssearch, &where); 151 152 /* Make sure we completely overlap with someone */ 153 if (ss == NULL) { 154 zfs_panic_recover("zfs: freeing free segment " 155 "(offset=%llu size=%llu)", 156 (longlong_t)start, (longlong_t)size); 157 return; 158 } 159 VERIFY3U(ss->ss_start, <=, start); 160 VERIFY3U(ss->ss_end, >=, end); 161 VERIFY(sm->sm_space - size <= sm->sm_size); 162 163 left_over = (ss->ss_start != start); 164 right_over = (ss->ss_end != end); 165 166 if (left_over && right_over) { 167 newseg = kmem_alloc(sizeof (*newseg), KM_SLEEP); 168 newseg->ss_start = end; 169 newseg->ss_end = ss->ss_end; 170 ss->ss_end = start; 171 avl_insert_here(&sm->sm_root, newseg, ss, AVL_AFTER); 172 } else if (left_over) { 173 ss->ss_end = start; 174 } else if (right_over) { 175 ss->ss_start = end; 176 } else { 177 avl_remove(&sm->sm_root, ss); 178 kmem_free(ss, sizeof (*ss)); 179 } 180 181 sm->sm_space -= size; 182 } 183 184 int 185 space_map_contains(space_map_t *sm, uint64_t start, uint64_t size) 186 { 187 avl_index_t where; 188 space_seg_t ssearch, *ss; 189 uint64_t end = start + size; 190 191 ASSERT(MUTEX_HELD(sm->sm_lock)); 192 VERIFY(size != 0); 193 VERIFY(P2PHASE(start, 1ULL << sm->sm_shift) == 0); 194 VERIFY(P2PHASE(size, 1ULL << sm->sm_shift) == 0); 195 196 ssearch.ss_start = start; 197 ssearch.ss_end = end; 198 ss = avl_find(&sm->sm_root, &ssearch, &where); 199 200 return (ss != NULL && ss->ss_start <= start && ss->ss_end >= end); 201 } 202 203 void 204 space_map_vacate(space_map_t *sm, space_map_func_t *func, space_map_t *mdest) 205 { 206 space_seg_t *ss; 207 void *cookie = NULL; 208 209 ASSERT(MUTEX_HELD(sm->sm_lock)); 210 211 while ((ss = avl_destroy_nodes(&sm->sm_root, &cookie)) != NULL) { 212 if (func != NULL) 213 func(mdest, ss->ss_start, ss->ss_end - ss->ss_start); 214 kmem_free(ss, sizeof (*ss)); 215 } 216 sm->sm_space = 0; 217 } 218 219 void 220 space_map_walk(space_map_t *sm, space_map_func_t *func, space_map_t *mdest) 221 { 222 space_seg_t *ss; 223 224 for (ss = avl_first(&sm->sm_root); ss; ss = AVL_NEXT(&sm->sm_root, ss)) 225 func(mdest, ss->ss_start, ss->ss_end - ss->ss_start); 226 } 227 228 void 229 space_map_excise(space_map_t *sm, uint64_t start, uint64_t size) 230 { 231 avl_tree_t *t = &sm->sm_root; 232 avl_index_t where; 233 space_seg_t *ss, search; 234 uint64_t end = start + size; 235 uint64_t rm_start, rm_end; 236 237 ASSERT(MUTEX_HELD(sm->sm_lock)); 238 239 search.ss_start = start; 240 search.ss_end = start; 241 242 for (;;) { 243 ss = avl_find(t, &search, &where); 244 245 if (ss == NULL) 246 ss = avl_nearest(t, where, AVL_AFTER); 247 248 if (ss == NULL || ss->ss_start >= end) 249 break; 250 251 rm_start = MAX(ss->ss_start, start); 252 rm_end = MIN(ss->ss_end, end); 253 254 space_map_remove(sm, rm_start, rm_end - rm_start); 255 } 256 } 257 258 /* 259 * Replace smd with the union of smd and sms. 260 */ 261 void 262 space_map_union(space_map_t *smd, space_map_t *sms) 263 { 264 avl_tree_t *t = &sms->sm_root; 265 space_seg_t *ss; 266 267 ASSERT(MUTEX_HELD(smd->sm_lock)); 268 269 /* 270 * For each source segment, remove any intersections with the 271 * destination, then add the source segment to the destination. 272 */ 273 for (ss = avl_first(t); ss != NULL; ss = AVL_NEXT(t, ss)) { 274 space_map_excise(smd, ss->ss_start, ss->ss_end - ss->ss_start); 275 space_map_add(smd, ss->ss_start, ss->ss_end - ss->ss_start); 276 } 277 } 278 279 /* 280 * Wait for any in-progress space_map_load() to complete. 281 */ 282 void 283 space_map_load_wait(space_map_t *sm) 284 { 285 ASSERT(MUTEX_HELD(sm->sm_lock)); 286 287 while (sm->sm_loading) 288 cv_wait(&sm->sm_load_cv, sm->sm_lock); 289 } 290 291 /* 292 * Note: space_map_load() will drop sm_lock across dmu_read() calls. 293 * The caller must be OK with this. 294 */ 295 int 296 space_map_load(space_map_t *sm, space_map_ops_t *ops, uint8_t maptype, 297 space_map_obj_t *smo, objset_t *os) 298 { 299 uint64_t *entry, *entry_map, *entry_map_end; 300 uint64_t bufsize, size, offset, end, space; 301 uint64_t mapstart = sm->sm_start; 302 int error = 0; 303 304 ASSERT(MUTEX_HELD(sm->sm_lock)); 305 306 space_map_load_wait(sm); 307 308 if (sm->sm_loaded) 309 return (0); 310 311 sm->sm_loading = B_TRUE; 312 end = smo->smo_objsize; 313 space = smo->smo_alloc; 314 315 ASSERT(sm->sm_ops == NULL); 316 VERIFY3U(sm->sm_space, ==, 0); 317 318 if (maptype == SM_FREE) { 319 space_map_add(sm, sm->sm_start, sm->sm_size); 320 space = sm->sm_size - space; 321 } 322 323 bufsize = 1ULL << SPACE_MAP_BLOCKSHIFT; 324 entry_map = zio_buf_alloc(bufsize); 325 326 mutex_exit(sm->sm_lock); 327 if (end > bufsize) 328 dmu_prefetch(os, smo->smo_object, bufsize, end - bufsize); 329 mutex_enter(sm->sm_lock); 330 331 for (offset = 0; offset < end; offset += bufsize) { 332 size = MIN(end - offset, bufsize); 333 VERIFY(P2PHASE(size, sizeof (uint64_t)) == 0); 334 VERIFY(size != 0); 335 336 dprintf("object=%llu offset=%llx size=%llx\n", 337 smo->smo_object, offset, size); 338 339 mutex_exit(sm->sm_lock); 340 error = dmu_read(os, smo->smo_object, offset, size, entry_map); 341 mutex_enter(sm->sm_lock); 342 if (error != 0) 343 break; 344 345 entry_map_end = entry_map + (size / sizeof (uint64_t)); 346 for (entry = entry_map; entry < entry_map_end; entry++) { 347 uint64_t e = *entry; 348 349 if (SM_DEBUG_DECODE(e)) /* Skip debug entries */ 350 continue; 351 352 (SM_TYPE_DECODE(e) == maptype ? 353 space_map_add : space_map_remove)(sm, 354 (SM_OFFSET_DECODE(e) << sm->sm_shift) + mapstart, 355 SM_RUN_DECODE(e) << sm->sm_shift); 356 } 357 } 358 359 if (error == 0) { 360 VERIFY3U(sm->sm_space, ==, space); 361 362 sm->sm_loaded = B_TRUE; 363 sm->sm_ops = ops; 364 if (ops != NULL) 365 ops->smop_load(sm); 366 } else { 367 space_map_vacate(sm, NULL, NULL); 368 } 369 370 zio_buf_free(entry_map, bufsize); 371 372 sm->sm_loading = B_FALSE; 373 374 cv_broadcast(&sm->sm_load_cv); 375 376 return (error); 377 } 378 379 void 380 space_map_unload(space_map_t *sm) 381 { 382 ASSERT(MUTEX_HELD(sm->sm_lock)); 383 384 if (sm->sm_loaded && sm->sm_ops != NULL) 385 sm->sm_ops->smop_unload(sm); 386 387 sm->sm_loaded = B_FALSE; 388 sm->sm_ops = NULL; 389 390 space_map_vacate(sm, NULL, NULL); 391 } 392 393 uint64_t 394 space_map_alloc(space_map_t *sm, uint64_t size) 395 { 396 uint64_t start; 397 398 start = sm->sm_ops->smop_alloc(sm, size); 399 if (start != -1ULL) 400 space_map_remove(sm, start, size); 401 return (start); 402 } 403 404 void 405 space_map_claim(space_map_t *sm, uint64_t start, uint64_t size) 406 { 407 sm->sm_ops->smop_claim(sm, start, size); 408 space_map_remove(sm, start, size); 409 } 410 411 void 412 space_map_free(space_map_t *sm, uint64_t start, uint64_t size) 413 { 414 space_map_add(sm, start, size); 415 sm->sm_ops->smop_free(sm, start, size); 416 } 417 418 /* 419 * Note: space_map_sync() will drop sm_lock across dmu_write() calls. 420 */ 421 void 422 space_map_sync(space_map_t *sm, uint8_t maptype, 423 space_map_obj_t *smo, objset_t *os, dmu_tx_t *tx) 424 { 425 spa_t *spa = dmu_objset_spa(os); 426 void *cookie = NULL; 427 space_seg_t *ss; 428 uint64_t bufsize, start, size, run_len; 429 uint64_t *entry, *entry_map, *entry_map_end; 430 431 ASSERT(MUTEX_HELD(sm->sm_lock)); 432 433 if (sm->sm_space == 0) 434 return; 435 436 dprintf("object %4llu, txg %llu, pass %d, %c, count %lu, space %llx\n", 437 smo->smo_object, dmu_tx_get_txg(tx), spa_sync_pass(spa), 438 maptype == SM_ALLOC ? 'A' : 'F', avl_numnodes(&sm->sm_root), 439 sm->sm_space); 440 441 if (maptype == SM_ALLOC) 442 smo->smo_alloc += sm->sm_space; 443 else 444 smo->smo_alloc -= sm->sm_space; 445 446 bufsize = (8 + avl_numnodes(&sm->sm_root)) * sizeof (uint64_t); 447 bufsize = MIN(bufsize, 1ULL << SPACE_MAP_BLOCKSHIFT); 448 entry_map = zio_buf_alloc(bufsize); 449 entry_map_end = entry_map + (bufsize / sizeof (uint64_t)); 450 entry = entry_map; 451 452 *entry++ = SM_DEBUG_ENCODE(1) | 453 SM_DEBUG_ACTION_ENCODE(maptype) | 454 SM_DEBUG_SYNCPASS_ENCODE(spa_sync_pass(spa)) | 455 SM_DEBUG_TXG_ENCODE(dmu_tx_get_txg(tx)); 456 457 while ((ss = avl_destroy_nodes(&sm->sm_root, &cookie)) != NULL) { 458 size = ss->ss_end - ss->ss_start; 459 start = (ss->ss_start - sm->sm_start) >> sm->sm_shift; 460 461 sm->sm_space -= size; 462 size >>= sm->sm_shift; 463 464 while (size) { 465 run_len = MIN(size, SM_RUN_MAX); 466 467 if (entry == entry_map_end) { 468 mutex_exit(sm->sm_lock); 469 dmu_write(os, smo->smo_object, smo->smo_objsize, 470 bufsize, entry_map, tx); 471 mutex_enter(sm->sm_lock); 472 smo->smo_objsize += bufsize; 473 entry = entry_map; 474 } 475 476 *entry++ = SM_OFFSET_ENCODE(start) | 477 SM_TYPE_ENCODE(maptype) | 478 SM_RUN_ENCODE(run_len); 479 480 start += run_len; 481 size -= run_len; 482 } 483 kmem_free(ss, sizeof (*ss)); 484 } 485 486 if (entry != entry_map) { 487 size = (entry - entry_map) * sizeof (uint64_t); 488 mutex_exit(sm->sm_lock); 489 dmu_write(os, smo->smo_object, smo->smo_objsize, 490 size, entry_map, tx); 491 mutex_enter(sm->sm_lock); 492 smo->smo_objsize += size; 493 } 494 495 zio_buf_free(entry_map, bufsize); 496 497 VERIFY3U(sm->sm_space, ==, 0); 498 } 499 500 void 501 space_map_truncate(space_map_obj_t *smo, objset_t *os, dmu_tx_t *tx) 502 { 503 VERIFY(dmu_free_range(os, smo->smo_object, 0, -1ULL, tx) == 0); 504 505 smo->smo_objsize = 0; 506 smo->smo_alloc = 0; 507 } 508