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 2007 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 if (ss != NULL && ss->ss_start <= start && ss->ss_end >= end) { 101 zfs_panic_recover("zfs: allocating allocated segment" 102 "(offset=%llu size=%llu)\n", 103 (longlong_t)start, (longlong_t)size); 104 return; 105 } 106 107 /* Make sure we don't overlap with either of our neighbors */ 108 VERIFY(ss == NULL); 109 110 ss_before = avl_nearest(&sm->sm_root, where, AVL_BEFORE); 111 ss_after = avl_nearest(&sm->sm_root, where, AVL_AFTER); 112 113 merge_before = (ss_before != NULL && ss_before->ss_end == start); 114 merge_after = (ss_after != NULL && ss_after->ss_start == end); 115 116 if (merge_before && merge_after) { 117 avl_remove(&sm->sm_root, ss_before); 118 ss_after->ss_start = ss_before->ss_start; 119 kmem_free(ss_before, sizeof (*ss_before)); 120 } else if (merge_before) { 121 ss_before->ss_end = end; 122 } else if (merge_after) { 123 ss_after->ss_start = start; 124 } else { 125 ss = kmem_alloc(sizeof (*ss), KM_SLEEP); 126 ss->ss_start = start; 127 ss->ss_end = end; 128 avl_insert(&sm->sm_root, ss, where); 129 } 130 131 sm->sm_space += size; 132 } 133 134 void 135 space_map_remove(space_map_t *sm, uint64_t start, uint64_t size) 136 { 137 avl_index_t where; 138 space_seg_t ssearch, *ss, *newseg; 139 uint64_t end = start + size; 140 int left_over, right_over; 141 142 ASSERT(MUTEX_HELD(sm->sm_lock)); 143 VERIFY(size != 0); 144 VERIFY(P2PHASE(start, 1ULL << sm->sm_shift) == 0); 145 VERIFY(P2PHASE(size, 1ULL << sm->sm_shift) == 0); 146 147 ssearch.ss_start = start; 148 ssearch.ss_end = end; 149 ss = avl_find(&sm->sm_root, &ssearch, &where); 150 151 /* Make sure we completely overlap with someone */ 152 if (ss == NULL) { 153 zfs_panic_recover("zfs: freeing free segment " 154 "(offset=%llu size=%llu)", 155 (longlong_t)start, (longlong_t)size); 156 return; 157 } 158 VERIFY3U(ss->ss_start, <=, start); 159 VERIFY3U(ss->ss_end, >=, end); 160 VERIFY(sm->sm_space - size <= sm->sm_size); 161 162 left_over = (ss->ss_start != start); 163 right_over = (ss->ss_end != end); 164 165 if (left_over && right_over) { 166 newseg = kmem_alloc(sizeof (*newseg), KM_SLEEP); 167 newseg->ss_start = end; 168 newseg->ss_end = ss->ss_end; 169 ss->ss_end = start; 170 avl_insert_here(&sm->sm_root, newseg, ss, AVL_AFTER); 171 } else if (left_over) { 172 ss->ss_end = start; 173 } else if (right_over) { 174 ss->ss_start = end; 175 } else { 176 avl_remove(&sm->sm_root, ss); 177 kmem_free(ss, sizeof (*ss)); 178 } 179 180 sm->sm_space -= size; 181 } 182 183 int 184 space_map_contains(space_map_t *sm, uint64_t start, uint64_t size) 185 { 186 avl_index_t where; 187 space_seg_t ssearch, *ss; 188 uint64_t end = start + size; 189 190 ASSERT(MUTEX_HELD(sm->sm_lock)); 191 VERIFY(size != 0); 192 VERIFY(P2PHASE(start, 1ULL << sm->sm_shift) == 0); 193 VERIFY(P2PHASE(size, 1ULL << sm->sm_shift) == 0); 194 195 ssearch.ss_start = start; 196 ssearch.ss_end = end; 197 ss = avl_find(&sm->sm_root, &ssearch, &where); 198 199 return (ss != NULL && ss->ss_start <= start && ss->ss_end >= end); 200 } 201 202 void 203 space_map_vacate(space_map_t *sm, space_map_func_t *func, space_map_t *mdest) 204 { 205 space_seg_t *ss; 206 void *cookie = NULL; 207 208 ASSERT(MUTEX_HELD(sm->sm_lock)); 209 210 while ((ss = avl_destroy_nodes(&sm->sm_root, &cookie)) != NULL) { 211 if (func != NULL) 212 func(mdest, ss->ss_start, ss->ss_end - ss->ss_start); 213 kmem_free(ss, sizeof (*ss)); 214 } 215 sm->sm_space = 0; 216 } 217 218 void 219 space_map_walk(space_map_t *sm, space_map_func_t *func, space_map_t *mdest) 220 { 221 space_seg_t *ss; 222 223 for (ss = avl_first(&sm->sm_root); ss; ss = AVL_NEXT(&sm->sm_root, ss)) 224 func(mdest, ss->ss_start, ss->ss_end - ss->ss_start); 225 } 226 227 void 228 space_map_excise(space_map_t *sm, uint64_t start, uint64_t size) 229 { 230 avl_tree_t *t = &sm->sm_root; 231 avl_index_t where; 232 space_seg_t *ss, search; 233 uint64_t end = start + size; 234 uint64_t rm_start, rm_end; 235 236 ASSERT(MUTEX_HELD(sm->sm_lock)); 237 238 search.ss_start = start; 239 search.ss_end = start; 240 241 for (;;) { 242 ss = avl_find(t, &search, &where); 243 244 if (ss == NULL) 245 ss = avl_nearest(t, where, AVL_AFTER); 246 247 if (ss == NULL || ss->ss_start >= end) 248 break; 249 250 rm_start = MAX(ss->ss_start, start); 251 rm_end = MIN(ss->ss_end, end); 252 253 space_map_remove(sm, rm_start, rm_end - rm_start); 254 } 255 } 256 257 /* 258 * Replace smd with the union of smd and sms. 259 */ 260 void 261 space_map_union(space_map_t *smd, space_map_t *sms) 262 { 263 avl_tree_t *t = &sms->sm_root; 264 space_seg_t *ss; 265 266 ASSERT(MUTEX_HELD(smd->sm_lock)); 267 268 /* 269 * For each source segment, remove any intersections with the 270 * destination, then add the source segment to the destination. 271 */ 272 for (ss = avl_first(t); ss != NULL; ss = AVL_NEXT(t, ss)) { 273 space_map_excise(smd, ss->ss_start, ss->ss_end - ss->ss_start); 274 space_map_add(smd, ss->ss_start, ss->ss_end - ss->ss_start); 275 } 276 } 277 278 /* 279 * Wait for any in-progress space_map_load() to complete. 280 */ 281 void 282 space_map_load_wait(space_map_t *sm) 283 { 284 ASSERT(MUTEX_HELD(sm->sm_lock)); 285 286 while (sm->sm_loading) 287 cv_wait(&sm->sm_load_cv, sm->sm_lock); 288 } 289 290 /* 291 * Note: space_map_load() will drop sm_lock across dmu_read() calls. 292 * The caller must be OK with this. 293 */ 294 int 295 space_map_load(space_map_t *sm, space_map_ops_t *ops, uint8_t maptype, 296 space_map_obj_t *smo, objset_t *os) 297 { 298 uint64_t *entry, *entry_map, *entry_map_end; 299 uint64_t bufsize, size, offset, end, space; 300 uint64_t mapstart = sm->sm_start; 301 int error = 0; 302 303 ASSERT(MUTEX_HELD(sm->sm_lock)); 304 305 space_map_load_wait(sm); 306 307 if (sm->sm_loaded) 308 return (0); 309 310 sm->sm_loading = B_TRUE; 311 end = smo->smo_objsize; 312 space = smo->smo_alloc; 313 314 ASSERT(sm->sm_ops == NULL); 315 VERIFY3U(sm->sm_space, ==, 0); 316 317 if (maptype == SM_FREE) { 318 space_map_add(sm, sm->sm_start, sm->sm_size); 319 space = sm->sm_size - space; 320 } 321 322 bufsize = 1ULL << SPACE_MAP_BLOCKSHIFT; 323 entry_map = zio_buf_alloc(bufsize); 324 325 mutex_exit(sm->sm_lock); 326 if (end > bufsize) 327 dmu_prefetch(os, smo->smo_object, bufsize, end - bufsize); 328 mutex_enter(sm->sm_lock); 329 330 for (offset = 0; offset < end; offset += bufsize) { 331 size = MIN(end - offset, bufsize); 332 VERIFY(P2PHASE(size, sizeof (uint64_t)) == 0); 333 VERIFY(size != 0); 334 335 dprintf("object=%llu offset=%llx size=%llx\n", 336 smo->smo_object, offset, size); 337 338 mutex_exit(sm->sm_lock); 339 error = dmu_read(os, smo->smo_object, offset, size, entry_map); 340 mutex_enter(sm->sm_lock); 341 if (error != 0) 342 goto out; 343 344 entry_map_end = entry_map + (size / sizeof (uint64_t)); 345 for (entry = entry_map; entry < entry_map_end; entry++) { 346 uint64_t e = *entry; 347 348 if (SM_DEBUG_DECODE(e)) /* Skip debug entries */ 349 continue; 350 351 (SM_TYPE_DECODE(e) == maptype ? 352 space_map_add : space_map_remove)(sm, 353 (SM_OFFSET_DECODE(e) << sm->sm_shift) + mapstart, 354 SM_RUN_DECODE(e) << sm->sm_shift); 355 } 356 } 357 VERIFY3U(sm->sm_space, ==, space); 358 359 sm->sm_loaded = B_TRUE; 360 sm->sm_ops = ops; 361 out: 362 zio_buf_free(entry_map, bufsize); 363 364 sm->sm_loading = B_FALSE; 365 366 cv_broadcast(&sm->sm_load_cv); 367 368 if (!error && ops != NULL) 369 ops->smop_load(sm); 370 371 return (error); 372 } 373 374 void 375 space_map_unload(space_map_t *sm) 376 { 377 ASSERT(MUTEX_HELD(sm->sm_lock)); 378 379 if (sm->sm_loaded && sm->sm_ops != NULL) 380 sm->sm_ops->smop_unload(sm); 381 382 sm->sm_loaded = B_FALSE; 383 sm->sm_ops = NULL; 384 385 space_map_vacate(sm, NULL, NULL); 386 } 387 388 uint64_t 389 space_map_alloc(space_map_t *sm, uint64_t size) 390 { 391 uint64_t start; 392 393 start = sm->sm_ops->smop_alloc(sm, size); 394 if (start != -1ULL) 395 space_map_remove(sm, start, size); 396 return (start); 397 } 398 399 void 400 space_map_claim(space_map_t *sm, uint64_t start, uint64_t size) 401 { 402 sm->sm_ops->smop_claim(sm, start, size); 403 space_map_remove(sm, start, size); 404 } 405 406 void 407 space_map_free(space_map_t *sm, uint64_t start, uint64_t size) 408 { 409 space_map_add(sm, start, size); 410 sm->sm_ops->smop_free(sm, start, size); 411 } 412 413 /* 414 * Note: space_map_sync() will drop sm_lock across dmu_write() calls. 415 */ 416 void 417 space_map_sync(space_map_t *sm, uint8_t maptype, 418 space_map_obj_t *smo, objset_t *os, dmu_tx_t *tx) 419 { 420 spa_t *spa = dmu_objset_spa(os); 421 void *cookie = NULL; 422 space_seg_t *ss; 423 uint64_t bufsize, start, size, run_len; 424 uint64_t *entry, *entry_map, *entry_map_end; 425 426 ASSERT(MUTEX_HELD(sm->sm_lock)); 427 428 if (sm->sm_space == 0) 429 return; 430 431 dprintf("object %4llu, txg %llu, pass %d, %c, count %lu, space %llx\n", 432 smo->smo_object, dmu_tx_get_txg(tx), spa_sync_pass(spa), 433 maptype == SM_ALLOC ? 'A' : 'F', avl_numnodes(&sm->sm_root), 434 sm->sm_space); 435 436 if (maptype == SM_ALLOC) 437 smo->smo_alloc += sm->sm_space; 438 else 439 smo->smo_alloc -= sm->sm_space; 440 441 bufsize = (8 + avl_numnodes(&sm->sm_root)) * sizeof (uint64_t); 442 bufsize = MIN(bufsize, 1ULL << SPACE_MAP_BLOCKSHIFT); 443 entry_map = zio_buf_alloc(bufsize); 444 entry_map_end = entry_map + (bufsize / sizeof (uint64_t)); 445 entry = entry_map; 446 447 *entry++ = SM_DEBUG_ENCODE(1) | 448 SM_DEBUG_ACTION_ENCODE(maptype) | 449 SM_DEBUG_SYNCPASS_ENCODE(spa_sync_pass(spa)) | 450 SM_DEBUG_TXG_ENCODE(dmu_tx_get_txg(tx)); 451 452 while ((ss = avl_destroy_nodes(&sm->sm_root, &cookie)) != NULL) { 453 size = ss->ss_end - ss->ss_start; 454 start = (ss->ss_start - sm->sm_start) >> sm->sm_shift; 455 456 sm->sm_space -= size; 457 size >>= sm->sm_shift; 458 459 while (size) { 460 run_len = MIN(size, SM_RUN_MAX); 461 462 if (entry == entry_map_end) { 463 mutex_exit(sm->sm_lock); 464 dmu_write(os, smo->smo_object, smo->smo_objsize, 465 bufsize, entry_map, tx); 466 mutex_enter(sm->sm_lock); 467 smo->smo_objsize += bufsize; 468 entry = entry_map; 469 } 470 471 *entry++ = SM_OFFSET_ENCODE(start) | 472 SM_TYPE_ENCODE(maptype) | 473 SM_RUN_ENCODE(run_len); 474 475 start += run_len; 476 size -= run_len; 477 } 478 kmem_free(ss, sizeof (*ss)); 479 } 480 481 if (entry != entry_map) { 482 size = (entry - entry_map) * sizeof (uint64_t); 483 mutex_exit(sm->sm_lock); 484 dmu_write(os, smo->smo_object, smo->smo_objsize, 485 size, entry_map, tx); 486 mutex_enter(sm->sm_lock); 487 smo->smo_objsize += size; 488 } 489 490 zio_buf_free(entry_map, bufsize); 491 492 VERIFY3U(sm->sm_space, ==, 0); 493 } 494 495 void 496 space_map_truncate(space_map_obj_t *smo, objset_t *os, dmu_tx_t *tx) 497 { 498 VERIFY(dmu_free_range(os, smo->smo_object, 0, -1ULL, tx) == 0); 499 500 smo->smo_objsize = 0; 501 smo->smo_alloc = 0; 502 } 503