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/space_map.h> 32 33 /* 34 * Space map routines. 35 * NOTE: caller is responsible for all locking. 36 */ 37 static int 38 space_map_seg_compare(const void *x1, const void *x2) 39 { 40 const space_seg_t *s1 = x1; 41 const space_seg_t *s2 = x2; 42 43 if (s1->ss_start < s2->ss_start) { 44 if (s1->ss_end > s2->ss_start) 45 return (0); 46 return (-1); 47 } 48 if (s1->ss_start > s2->ss_start) { 49 if (s1->ss_start < s2->ss_end) 50 return (0); 51 return (1); 52 } 53 return (0); 54 } 55 56 void 57 space_map_create(space_map_t *sm, uint64_t start, uint64_t size, uint64_t shift, 58 kmutex_t *lp) 59 { 60 avl_create(&sm->sm_root, space_map_seg_compare, 61 sizeof (space_seg_t), offsetof(struct space_seg, ss_node)); 62 sm->sm_start = start; 63 sm->sm_end = start + size; 64 sm->sm_size = size; 65 sm->sm_shift = shift; 66 sm->sm_space = 0; 67 sm->sm_lock = lp; 68 } 69 70 void 71 space_map_destroy(space_map_t *sm) 72 { 73 VERIFY3U(sm->sm_space, ==, 0); 74 avl_destroy(&sm->sm_root); 75 } 76 77 void 78 space_map_add(space_map_t *sm, uint64_t start, uint64_t size) 79 { 80 avl_index_t where; 81 space_seg_t ssearch, *ss_before, *ss_after, *ss; 82 uint64_t end = start + size; 83 int merge_before, merge_after; 84 85 ASSERT(MUTEX_HELD(sm->sm_lock)); 86 VERIFY(size != 0); 87 VERIFY3U(start, >=, sm->sm_start); 88 VERIFY3U(end, <=, sm->sm_end); 89 VERIFY(sm->sm_space + size <= sm->sm_size); 90 VERIFY(P2PHASE(start, 1ULL << sm->sm_shift) == 0); 91 VERIFY(P2PHASE(size, 1ULL << sm->sm_shift) == 0); 92 93 ssearch.ss_start = start; 94 ssearch.ss_end = end; 95 ss = avl_find(&sm->sm_root, &ssearch, &where); 96 97 /* Make sure we don't overlap with either of our neighbors */ 98 VERIFY(ss == NULL); 99 100 ss_before = avl_nearest(&sm->sm_root, where, AVL_BEFORE); 101 ss_after = avl_nearest(&sm->sm_root, where, AVL_AFTER); 102 103 merge_before = (ss_before != NULL && ss_before->ss_end == start); 104 merge_after = (ss_after != NULL && ss_after->ss_start == end); 105 106 if (merge_before && merge_after) { 107 avl_remove(&sm->sm_root, ss_before); 108 ss_after->ss_start = ss_before->ss_start; 109 kmem_free(ss_before, sizeof (*ss_before)); 110 } else if (merge_before) { 111 ss_before->ss_end = end; 112 } else if (merge_after) { 113 ss_after->ss_start = start; 114 } else { 115 ss = kmem_alloc(sizeof (*ss), KM_SLEEP); 116 ss->ss_start = start; 117 ss->ss_end = end; 118 avl_insert(&sm->sm_root, ss, where); 119 } 120 121 sm->sm_space += size; 122 } 123 124 void 125 space_map_remove(space_map_t *sm, uint64_t start, uint64_t size) 126 { 127 avl_index_t where; 128 space_seg_t ssearch, *ss, *newseg; 129 uint64_t end = start + size; 130 int left_over, right_over; 131 132 ASSERT(MUTEX_HELD(sm->sm_lock)); 133 VERIFY(size != 0); 134 VERIFY(P2PHASE(start, 1ULL << sm->sm_shift) == 0); 135 VERIFY(P2PHASE(size, 1ULL << sm->sm_shift) == 0); 136 137 ssearch.ss_start = start; 138 ssearch.ss_end = end; 139 ss = avl_find(&sm->sm_root, &ssearch, &where); 140 141 /* Make sure we completely overlap with someone */ 142 VERIFY(ss != NULL); 143 VERIFY3U(ss->ss_start, <=, start); 144 VERIFY3U(ss->ss_end, >=, end); 145 VERIFY(sm->sm_space - size <= sm->sm_size); 146 147 left_over = (ss->ss_start != start); 148 right_over = (ss->ss_end != end); 149 150 if (left_over && right_over) { 151 newseg = kmem_alloc(sizeof (*newseg), KM_SLEEP); 152 newseg->ss_start = end; 153 newseg->ss_end = ss->ss_end; 154 ss->ss_end = start; 155 avl_insert_here(&sm->sm_root, newseg, ss, AVL_AFTER); 156 } else if (left_over) { 157 ss->ss_end = start; 158 } else if (right_over) { 159 ss->ss_start = end; 160 } else { 161 avl_remove(&sm->sm_root, ss); 162 kmem_free(ss, sizeof (*ss)); 163 } 164 165 sm->sm_space -= size; 166 } 167 168 int 169 space_map_contains(space_map_t *sm, uint64_t start, uint64_t size) 170 { 171 avl_index_t where; 172 space_seg_t ssearch, *ss; 173 uint64_t end = start + size; 174 175 ASSERT(MUTEX_HELD(sm->sm_lock)); 176 VERIFY(size != 0); 177 VERIFY(P2PHASE(start, 1ULL << sm->sm_shift) == 0); 178 VERIFY(P2PHASE(size, 1ULL << sm->sm_shift) == 0); 179 180 ssearch.ss_start = start; 181 ssearch.ss_end = end; 182 ss = avl_find(&sm->sm_root, &ssearch, &where); 183 184 return (ss != NULL && ss->ss_start <= start && ss->ss_end >= end); 185 } 186 187 void 188 space_map_vacate(space_map_t *sm, space_map_func_t *func, space_map_t *mdest) 189 { 190 space_seg_t *ss; 191 void *cookie = NULL; 192 193 ASSERT(MUTEX_HELD(sm->sm_lock)); 194 195 while ((ss = avl_destroy_nodes(&sm->sm_root, &cookie)) != NULL) { 196 if (func != NULL) 197 func(mdest, ss->ss_start, ss->ss_end - ss->ss_start); 198 kmem_free(ss, sizeof (*ss)); 199 } 200 sm->sm_space = 0; 201 } 202 203 void 204 space_map_iterate(space_map_t *sm, space_map_func_t *func, space_map_t *mdest) 205 { 206 space_seg_t *ss; 207 208 for (ss = avl_first(&sm->sm_root); ss; ss = AVL_NEXT(&sm->sm_root, ss)) 209 func(mdest, ss->ss_start, ss->ss_end - ss->ss_start); 210 } 211 212 void 213 space_map_merge(space_map_t *src, space_map_t *dest) 214 { 215 space_map_vacate(src, space_map_add, dest); 216 } 217 218 void 219 space_map_excise(space_map_t *sm, uint64_t start, uint64_t size) 220 { 221 avl_tree_t *t = &sm->sm_root; 222 avl_index_t where; 223 space_seg_t *ss, search; 224 uint64_t end = start + size; 225 uint64_t rm_start, rm_end; 226 227 ASSERT(MUTEX_HELD(sm->sm_lock)); 228 229 search.ss_start = start; 230 search.ss_end = start; 231 232 for (;;) { 233 ss = avl_find(t, &search, &where); 234 235 if (ss == NULL) 236 ss = avl_nearest(t, where, AVL_AFTER); 237 238 if (ss == NULL || ss->ss_start >= end) 239 break; 240 241 rm_start = MAX(ss->ss_start, start); 242 rm_end = MIN(ss->ss_end, end); 243 244 space_map_remove(sm, rm_start, rm_end - rm_start); 245 } 246 } 247 248 /* 249 * Replace smd with the union of smd and sms. 250 */ 251 void 252 space_map_union(space_map_t *smd, space_map_t *sms) 253 { 254 avl_tree_t *t = &sms->sm_root; 255 space_seg_t *ss; 256 257 ASSERT(MUTEX_HELD(smd->sm_lock)); 258 259 /* 260 * For each source segment, remove any intersections with the 261 * destination, then add the source segment to the destination. 262 */ 263 for (ss = avl_first(t); ss != NULL; ss = AVL_NEXT(t, ss)) { 264 space_map_excise(smd, ss->ss_start, ss->ss_end - ss->ss_start); 265 space_map_add(smd, ss->ss_start, ss->ss_end - ss->ss_start); 266 } 267 } 268 269 int 270 space_map_load(space_map_t *sm, space_map_obj_t *smo, uint8_t maptype, 271 objset_t *os, uint64_t end, uint64_t space) 272 { 273 uint64_t *entry, *entry_map, *entry_map_end; 274 uint64_t bufsize, size, offset; 275 uint64_t mapstart = sm->sm_start; 276 277 ASSERT(MUTEX_HELD(sm->sm_lock)); 278 VERIFY3U(sm->sm_space, ==, 0); 279 280 bufsize = MIN(end, SPACE_MAP_CHUNKSIZE); 281 entry_map = kmem_alloc(bufsize, KM_SLEEP); 282 283 if (maptype == SM_FREE) { 284 space_map_add(sm, sm->sm_start, sm->sm_size); 285 space = sm->sm_size - space; 286 } 287 288 for (offset = 0; offset < end; offset += bufsize) { 289 size = MIN(end - offset, bufsize); 290 VERIFY(P2PHASE(size, sizeof (uint64_t)) == 0); 291 VERIFY(size != 0); 292 293 dprintf("object=%llu offset=%llx size=%llx\n", 294 smo->smo_object, offset, size); 295 VERIFY(0 == dmu_read(os, smo->smo_object, offset, size, 296 entry_map)); 297 298 entry_map_end = entry_map + (size / sizeof (uint64_t)); 299 for (entry = entry_map; entry < entry_map_end; entry++) { 300 uint64_t e = *entry; 301 302 if (SM_DEBUG_DECODE(e)) /* Skip debug entries */ 303 continue; 304 305 (SM_TYPE_DECODE(e) == maptype ? 306 space_map_add : space_map_remove)(sm, 307 (SM_OFFSET_DECODE(e) << sm->sm_shift) + mapstart, 308 SM_RUN_DECODE(e) << sm->sm_shift); 309 } 310 } 311 VERIFY3U(sm->sm_space, ==, space); 312 313 kmem_free(entry_map, bufsize); 314 315 return (0); 316 } 317 318 void 319 space_map_sync(space_map_t *sm, space_map_t *dest, space_map_obj_t *smo, 320 uint8_t maptype, objset_t *os, dmu_tx_t *tx) 321 { 322 spa_t *spa = dmu_objset_spa(os); 323 void *cookie = NULL; 324 space_seg_t *ss; 325 uint64_t bufsize, start, size, run_len; 326 uint64_t *entry, *entry_map, *entry_map_end; 327 328 ASSERT(MUTEX_HELD(sm->sm_lock)); 329 330 if (sm->sm_space == 0) 331 return; 332 333 dprintf("object %4llu, txg %llu, pass %d, %c, count %lu, space %llx\n", 334 smo->smo_object, dmu_tx_get_txg(tx), spa_sync_pass(spa), 335 maptype == SM_ALLOC ? 'A' : 'F', avl_numnodes(&sm->sm_root), 336 sm->sm_space); 337 338 bufsize = (8 + avl_numnodes(&sm->sm_root)) * sizeof (uint64_t); 339 bufsize = MIN(bufsize, SPACE_MAP_CHUNKSIZE); 340 entry_map = kmem_alloc(bufsize, KM_SLEEP); 341 entry_map_end = entry_map + (bufsize / sizeof (uint64_t)); 342 entry = entry_map; 343 344 *entry++ = SM_DEBUG_ENCODE(1) | 345 SM_DEBUG_ACTION_ENCODE(maptype) | 346 SM_DEBUG_SYNCPASS_ENCODE(spa_sync_pass(spa)) | 347 SM_DEBUG_TXG_ENCODE(dmu_tx_get_txg(tx)); 348 349 while ((ss = avl_destroy_nodes(&sm->sm_root, &cookie)) != NULL) { 350 size = ss->ss_end - ss->ss_start; 351 start = (ss->ss_start - sm->sm_start) >> sm->sm_shift; 352 353 if (dest) 354 space_map_add(dest, ss->ss_start, size); 355 356 sm->sm_space -= size; 357 size >>= sm->sm_shift; 358 359 while (size) { 360 run_len = MIN(size, SM_RUN_MAX); 361 362 if (entry == entry_map_end) { 363 dmu_write(os, smo->smo_object, smo->smo_objsize, 364 bufsize, entry_map, tx); 365 smo->smo_objsize += bufsize; 366 entry = entry_map; 367 } 368 369 *entry++ = SM_OFFSET_ENCODE(start) | 370 SM_TYPE_ENCODE(maptype) | 371 SM_RUN_ENCODE(run_len); 372 373 start += run_len; 374 size -= run_len; 375 } 376 kmem_free(ss, sizeof (*ss)); 377 } 378 379 if (entry != entry_map) { 380 size = (entry - entry_map) * sizeof (uint64_t); 381 dmu_write(os, smo->smo_object, smo->smo_objsize, 382 size, entry_map, tx); 383 smo->smo_objsize += size; 384 } 385 386 kmem_free(entry_map, bufsize); 387 388 VERIFY3U(sm->sm_space, ==, 0); 389 } 390 391 void 392 space_map_write(space_map_t *sm, space_map_obj_t *smo, objset_t *os, 393 dmu_tx_t *tx) 394 { 395 uint64_t oldsize = smo->smo_objsize; 396 397 VERIFY(0 == dmu_free_range(os, smo->smo_object, 0, 398 smo->smo_objsize, tx)); 399 400 smo->smo_objsize = 0; 401 402 VERIFY3U(sm->sm_space, ==, smo->smo_alloc); 403 space_map_sync(sm, NULL, smo, SM_ALLOC, os, tx); 404 405 dprintf("write sm object %llu from %llu to %llu bytes in txg %llu\n", 406 smo->smo_object, oldsize, smo->smo_objsize, dmu_tx_get_txg(tx)); 407 } 408