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 2006 Sun Microsystems, Inc. All rights reserved. 23 * Use is subject to license terms. 24 */ 25 26 #pragma ident "%Z%%M% %I% %E% SMI" 27 28 #include <sys/zfs_context.h> 29 #include <sys/spa.h> 30 #include <sys/dmu.h> 31 #include <sys/zio.h> 32 #include <sys/space_map.h> 33 34 /* 35 * Space map routines. 36 * NOTE: caller is responsible for all locking. 37 */ 38 static int 39 space_map_seg_compare(const void *x1, const void *x2) 40 { 41 const space_seg_t *s1 = x1; 42 const space_seg_t *s2 = x2; 43 44 if (s1->ss_start < s2->ss_start) { 45 if (s1->ss_end > s2->ss_start) 46 return (0); 47 return (-1); 48 } 49 if (s1->ss_start > s2->ss_start) { 50 if (s1->ss_start < s2->ss_end) 51 return (0); 52 return (1); 53 } 54 return (0); 55 } 56 57 void 58 space_map_create(space_map_t *sm, uint64_t start, uint64_t size, uint8_t shift, 59 kmutex_t *lp) 60 { 61 bzero(sm, sizeof (*sm)); 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 } 79 80 void 81 space_map_add(space_map_t *sm, uint64_t start, uint64_t size) 82 { 83 avl_index_t where; 84 space_seg_t ssearch, *ss_before, *ss_after, *ss; 85 uint64_t end = start + size; 86 int merge_before, merge_after; 87 88 ASSERT(MUTEX_HELD(sm->sm_lock)); 89 VERIFY(size != 0); 90 VERIFY3U(start, >=, sm->sm_start); 91 VERIFY3U(end, <=, sm->sm_start + sm->sm_size); 92 VERIFY(sm->sm_space + size <= sm->sm_size); 93 VERIFY(P2PHASE(start, 1ULL << sm->sm_shift) == 0); 94 VERIFY(P2PHASE(size, 1ULL << sm->sm_shift) == 0); 95 96 ssearch.ss_start = start; 97 ssearch.ss_end = end; 98 ss = avl_find(&sm->sm_root, &ssearch, &where); 99 100 /* Make sure we don't overlap with either of our neighbors */ 101 VERIFY(ss == NULL); 102 103 ss_before = avl_nearest(&sm->sm_root, where, AVL_BEFORE); 104 ss_after = avl_nearest(&sm->sm_root, where, AVL_AFTER); 105 106 merge_before = (ss_before != NULL && ss_before->ss_end == start); 107 merge_after = (ss_after != NULL && ss_after->ss_start == end); 108 109 if (merge_before && merge_after) { 110 avl_remove(&sm->sm_root, ss_before); 111 ss_after->ss_start = ss_before->ss_start; 112 kmem_free(ss_before, sizeof (*ss_before)); 113 } else if (merge_before) { 114 ss_before->ss_end = end; 115 } else if (merge_after) { 116 ss_after->ss_start = start; 117 } else { 118 ss = kmem_alloc(sizeof (*ss), KM_SLEEP); 119 ss->ss_start = start; 120 ss->ss_end = end; 121 avl_insert(&sm->sm_root, ss, where); 122 } 123 124 sm->sm_space += size; 125 } 126 127 void 128 space_map_remove(space_map_t *sm, uint64_t start, uint64_t size) 129 { 130 avl_index_t where; 131 space_seg_t ssearch, *ss, *newseg; 132 uint64_t end = start + size; 133 int left_over, right_over; 134 135 ASSERT(MUTEX_HELD(sm->sm_lock)); 136 VERIFY(size != 0); 137 VERIFY(P2PHASE(start, 1ULL << sm->sm_shift) == 0); 138 VERIFY(P2PHASE(size, 1ULL << sm->sm_shift) == 0); 139 140 ssearch.ss_start = start; 141 ssearch.ss_end = end; 142 ss = avl_find(&sm->sm_root, &ssearch, &where); 143 144 /* Make sure we completely overlap with someone */ 145 VERIFY(ss != NULL); 146 VERIFY3U(ss->ss_start, <=, start); 147 VERIFY3U(ss->ss_end, >=, end); 148 VERIFY(sm->sm_space - size <= sm->sm_size); 149 150 left_over = (ss->ss_start != start); 151 right_over = (ss->ss_end != end); 152 153 if (left_over && right_over) { 154 newseg = kmem_alloc(sizeof (*newseg), KM_SLEEP); 155 newseg->ss_start = end; 156 newseg->ss_end = ss->ss_end; 157 ss->ss_end = start; 158 avl_insert_here(&sm->sm_root, newseg, ss, AVL_AFTER); 159 } else if (left_over) { 160 ss->ss_end = start; 161 } else if (right_over) { 162 ss->ss_start = end; 163 } else { 164 avl_remove(&sm->sm_root, ss); 165 kmem_free(ss, sizeof (*ss)); 166 } 167 168 sm->sm_space -= size; 169 } 170 171 int 172 space_map_contains(space_map_t *sm, uint64_t start, uint64_t size) 173 { 174 avl_index_t where; 175 space_seg_t ssearch, *ss; 176 uint64_t end = start + size; 177 178 ASSERT(MUTEX_HELD(sm->sm_lock)); 179 VERIFY(size != 0); 180 VERIFY(P2PHASE(start, 1ULL << sm->sm_shift) == 0); 181 VERIFY(P2PHASE(size, 1ULL << sm->sm_shift) == 0); 182 183 ssearch.ss_start = start; 184 ssearch.ss_end = end; 185 ss = avl_find(&sm->sm_root, &ssearch, &where); 186 187 return (ss != NULL && ss->ss_start <= start && ss->ss_end >= end); 188 } 189 190 void 191 space_map_vacate(space_map_t *sm, space_map_func_t *func, space_map_t *mdest) 192 { 193 space_seg_t *ss; 194 void *cookie = NULL; 195 196 ASSERT(MUTEX_HELD(sm->sm_lock)); 197 198 while ((ss = avl_destroy_nodes(&sm->sm_root, &cookie)) != NULL) { 199 if (func != NULL) 200 func(mdest, ss->ss_start, ss->ss_end - ss->ss_start); 201 kmem_free(ss, sizeof (*ss)); 202 } 203 sm->sm_space = 0; 204 } 205 206 void 207 space_map_walk(space_map_t *sm, space_map_func_t *func, space_map_t *mdest) 208 { 209 space_seg_t *ss; 210 211 for (ss = avl_first(&sm->sm_root); ss; ss = AVL_NEXT(&sm->sm_root, ss)) 212 func(mdest, ss->ss_start, ss->ss_end - ss->ss_start); 213 } 214 215 void 216 space_map_excise(space_map_t *sm, uint64_t start, uint64_t size) 217 { 218 avl_tree_t *t = &sm->sm_root; 219 avl_index_t where; 220 space_seg_t *ss, search; 221 uint64_t end = start + size; 222 uint64_t rm_start, rm_end; 223 224 ASSERT(MUTEX_HELD(sm->sm_lock)); 225 226 search.ss_start = start; 227 search.ss_end = start; 228 229 for (;;) { 230 ss = avl_find(t, &search, &where); 231 232 if (ss == NULL) 233 ss = avl_nearest(t, where, AVL_AFTER); 234 235 if (ss == NULL || ss->ss_start >= end) 236 break; 237 238 rm_start = MAX(ss->ss_start, start); 239 rm_end = MIN(ss->ss_end, end); 240 241 space_map_remove(sm, rm_start, rm_end - rm_start); 242 } 243 } 244 245 /* 246 * Replace smd with the union of smd and sms. 247 */ 248 void 249 space_map_union(space_map_t *smd, space_map_t *sms) 250 { 251 avl_tree_t *t = &sms->sm_root; 252 space_seg_t *ss; 253 254 ASSERT(MUTEX_HELD(smd->sm_lock)); 255 256 /* 257 * For each source segment, remove any intersections with the 258 * destination, then add the source segment to the destination. 259 */ 260 for (ss = avl_first(t); ss != NULL; ss = AVL_NEXT(t, ss)) { 261 space_map_excise(smd, ss->ss_start, ss->ss_end - ss->ss_start); 262 space_map_add(smd, ss->ss_start, ss->ss_end - ss->ss_start); 263 } 264 } 265 266 /* 267 * Wait for any in-progress space_map_load() to complete. 268 */ 269 void 270 space_map_load_wait(space_map_t *sm) 271 { 272 ASSERT(MUTEX_HELD(sm->sm_lock)); 273 274 while (sm->sm_loading) 275 cv_wait(&sm->sm_load_cv, sm->sm_lock); 276 } 277 278 /* 279 * Note: space_map_load() will drop sm_lock across dmu_read() calls. 280 * The caller must be OK with this. 281 */ 282 int 283 space_map_load(space_map_t *sm, space_map_ops_t *ops, uint8_t maptype, 284 space_map_obj_t *smo, objset_t *os) 285 { 286 uint64_t *entry, *entry_map, *entry_map_end; 287 uint64_t bufsize, size, offset; 288 uint64_t mapstart = sm->sm_start; 289 uint64_t end = smo->smo_objsize; 290 uint64_t space = smo->smo_alloc; 291 292 ASSERT(MUTEX_HELD(sm->sm_lock)); 293 294 space_map_load_wait(sm); 295 296 if (sm->sm_loaded) 297 return (0); 298 299 sm->sm_loading = B_TRUE; 300 301 ASSERT(sm->sm_ops == NULL); 302 VERIFY3U(sm->sm_space, ==, 0); 303 304 if (maptype == SM_FREE) { 305 space_map_add(sm, sm->sm_start, sm->sm_size); 306 space = sm->sm_size - space; 307 } 308 309 bufsize = 1ULL << SPACE_MAP_BLOCKSHIFT; 310 entry_map = zio_buf_alloc(bufsize); 311 312 mutex_exit(sm->sm_lock); 313 if (end > bufsize) 314 dmu_prefetch(os, smo->smo_object, bufsize, end - bufsize); 315 mutex_enter(sm->sm_lock); 316 317 for (offset = 0; offset < end; offset += bufsize) { 318 size = MIN(end - offset, bufsize); 319 VERIFY(P2PHASE(size, sizeof (uint64_t)) == 0); 320 VERIFY(size != 0); 321 322 dprintf("object=%llu offset=%llx size=%llx\n", 323 smo->smo_object, offset, size); 324 325 mutex_exit(sm->sm_lock); 326 VERIFY3U(dmu_read(os, smo->smo_object, offset, size, 327 entry_map), ==, 0); 328 mutex_enter(sm->sm_lock); 329 330 entry_map_end = entry_map + (size / sizeof (uint64_t)); 331 for (entry = entry_map; entry < entry_map_end; entry++) { 332 uint64_t e = *entry; 333 334 if (SM_DEBUG_DECODE(e)) /* Skip debug entries */ 335 continue; 336 337 (SM_TYPE_DECODE(e) == maptype ? 338 space_map_add : space_map_remove)(sm, 339 (SM_OFFSET_DECODE(e) << sm->sm_shift) + mapstart, 340 SM_RUN_DECODE(e) << sm->sm_shift); 341 } 342 } 343 VERIFY3U(sm->sm_space, ==, space); 344 345 zio_buf_free(entry_map, bufsize); 346 347 sm->sm_loading = B_FALSE; 348 sm->sm_loaded = B_TRUE; 349 sm->sm_ops = ops; 350 351 cv_broadcast(&sm->sm_load_cv); 352 353 if (ops != NULL) 354 ops->smop_load(sm); 355 356 return (0); 357 } 358 359 void 360 space_map_unload(space_map_t *sm) 361 { 362 ASSERT(MUTEX_HELD(sm->sm_lock)); 363 364 if (sm->sm_loaded && sm->sm_ops != NULL) 365 sm->sm_ops->smop_unload(sm); 366 367 sm->sm_loaded = B_FALSE; 368 sm->sm_ops = NULL; 369 370 space_map_vacate(sm, NULL, NULL); 371 } 372 373 uint64_t 374 space_map_alloc(space_map_t *sm, uint64_t size) 375 { 376 uint64_t start; 377 378 start = sm->sm_ops->smop_alloc(sm, size); 379 if (start != -1ULL) 380 space_map_remove(sm, start, size); 381 return (start); 382 } 383 384 void 385 space_map_claim(space_map_t *sm, uint64_t start, uint64_t size) 386 { 387 sm->sm_ops->smop_claim(sm, start, size); 388 space_map_remove(sm, start, size); 389 } 390 391 void 392 space_map_free(space_map_t *sm, uint64_t start, uint64_t size) 393 { 394 space_map_add(sm, start, size); 395 sm->sm_ops->smop_free(sm, start, size); 396 } 397 398 /* 399 * Note: space_map_sync() will drop sm_lock across dmu_write() calls. 400 */ 401 void 402 space_map_sync(space_map_t *sm, uint8_t maptype, 403 space_map_obj_t *smo, objset_t *os, dmu_tx_t *tx) 404 { 405 spa_t *spa = dmu_objset_spa(os); 406 void *cookie = NULL; 407 space_seg_t *ss; 408 uint64_t bufsize, start, size, run_len; 409 uint64_t *entry, *entry_map, *entry_map_end; 410 411 ASSERT(MUTEX_HELD(sm->sm_lock)); 412 413 if (sm->sm_space == 0) 414 return; 415 416 dprintf("object %4llu, txg %llu, pass %d, %c, count %lu, space %llx\n", 417 smo->smo_object, dmu_tx_get_txg(tx), spa_sync_pass(spa), 418 maptype == SM_ALLOC ? 'A' : 'F', avl_numnodes(&sm->sm_root), 419 sm->sm_space); 420 421 if (maptype == SM_ALLOC) 422 smo->smo_alloc += sm->sm_space; 423 else 424 smo->smo_alloc -= sm->sm_space; 425 426 bufsize = (8 + avl_numnodes(&sm->sm_root)) * sizeof (uint64_t); 427 bufsize = MIN(bufsize, 1ULL << SPACE_MAP_BLOCKSHIFT); 428 entry_map = zio_buf_alloc(bufsize); 429 entry_map_end = entry_map + (bufsize / sizeof (uint64_t)); 430 entry = entry_map; 431 432 *entry++ = SM_DEBUG_ENCODE(1) | 433 SM_DEBUG_ACTION_ENCODE(maptype) | 434 SM_DEBUG_SYNCPASS_ENCODE(spa_sync_pass(spa)) | 435 SM_DEBUG_TXG_ENCODE(dmu_tx_get_txg(tx)); 436 437 while ((ss = avl_destroy_nodes(&sm->sm_root, &cookie)) != NULL) { 438 size = ss->ss_end - ss->ss_start; 439 start = (ss->ss_start - sm->sm_start) >> sm->sm_shift; 440 441 sm->sm_space -= size; 442 size >>= sm->sm_shift; 443 444 while (size) { 445 run_len = MIN(size, SM_RUN_MAX); 446 447 if (entry == entry_map_end) { 448 mutex_exit(sm->sm_lock); 449 dmu_write(os, smo->smo_object, smo->smo_objsize, 450 bufsize, entry_map, tx); 451 mutex_enter(sm->sm_lock); 452 smo->smo_objsize += bufsize; 453 entry = entry_map; 454 } 455 456 *entry++ = SM_OFFSET_ENCODE(start) | 457 SM_TYPE_ENCODE(maptype) | 458 SM_RUN_ENCODE(run_len); 459 460 start += run_len; 461 size -= run_len; 462 } 463 kmem_free(ss, sizeof (*ss)); 464 } 465 466 if (entry != entry_map) { 467 size = (entry - entry_map) * sizeof (uint64_t); 468 mutex_exit(sm->sm_lock); 469 dmu_write(os, smo->smo_object, smo->smo_objsize, 470 size, entry_map, tx); 471 mutex_enter(sm->sm_lock); 472 smo->smo_objsize += size; 473 } 474 475 zio_buf_free(entry_map, bufsize); 476 477 VERIFY3U(sm->sm_space, ==, 0); 478 } 479 480 void 481 space_map_truncate(space_map_obj_t *smo, objset_t *os, dmu_tx_t *tx) 482 { 483 VERIFY(dmu_free_range(os, smo->smo_object, 0, -1ULL, tx) == 0); 484 485 smo->smo_objsize = 0; 486 smo->smo_alloc = 0; 487 } 488