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 /* 23 * Copyright 2010 Sun Microsystems, Inc. All rights reserved. 24 * Use is subject to license terms. 25 */ 26 27 #include <sys/spa.h> 28 #include <sys/spa_impl.h> 29 #include <sys/zap.h> 30 #include <sys/dsl_synctask.h> 31 #include <sys/dmu_tx.h> 32 #include <sys/dmu_objset.h> 33 #include <sys/utsname.h> 34 #include <sys/cmn_err.h> 35 #include <sys/sunddi.h> 36 #ifdef _KERNEL 37 #include <sys/zone.h> 38 #endif 39 40 /* 41 * Routines to manage the on-disk history log. 42 * 43 * The history log is stored as a dmu object containing 44 * <packed record length, record nvlist> tuples. 45 * 46 * Where "record nvlist" is a nvlist containing uint64_ts and strings, and 47 * "packed record length" is the packed length of the "record nvlist" stored 48 * as a little endian uint64_t. 49 * 50 * The log is implemented as a ring buffer, though the original creation 51 * of the pool ('zpool create') is never overwritten. 52 * 53 * The history log is tracked as object 'spa_t::spa_history'. The bonus buffer 54 * of 'spa_history' stores the offsets for logging/retrieving history as 55 * 'spa_history_phys_t'. 'sh_pool_create_len' is the ending offset in bytes of 56 * where the 'zpool create' record is stored. This allows us to never 57 * overwrite the original creation of the pool. 'sh_phys_max_off' is the 58 * physical ending offset in bytes of the log. This tells you the length of 59 * the buffer. 'sh_eof' is the logical EOF (in bytes). Whenever a record 60 * is added, 'sh_eof' is incremented by the the size of the record. 61 * 'sh_eof' is never decremented. 'sh_bof' is the logical BOF (in bytes). 62 * This is where the consumer should start reading from after reading in 63 * the 'zpool create' portion of the log. 64 * 65 * 'sh_records_lost' keeps track of how many records have been overwritten 66 * and permanently lost. 67 */ 68 69 /* convert a logical offset to physical */ 70 static uint64_t 71 spa_history_log_to_phys(uint64_t log_off, spa_history_phys_t *shpp) 72 { 73 uint64_t phys_len; 74 75 phys_len = shpp->sh_phys_max_off - shpp->sh_pool_create_len; 76 return ((log_off - shpp->sh_pool_create_len) % phys_len 77 + shpp->sh_pool_create_len); 78 } 79 80 void 81 spa_history_create_obj(spa_t *spa, dmu_tx_t *tx) 82 { 83 dmu_buf_t *dbp; 84 spa_history_phys_t *shpp; 85 objset_t *mos = spa->spa_meta_objset; 86 87 ASSERT(spa->spa_history == 0); 88 spa->spa_history = dmu_object_alloc(mos, DMU_OT_SPA_HISTORY, 89 SPA_MAXBLOCKSIZE, DMU_OT_SPA_HISTORY_OFFSETS, 90 sizeof (spa_history_phys_t), tx); 91 92 VERIFY(zap_add(mos, DMU_POOL_DIRECTORY_OBJECT, 93 DMU_POOL_HISTORY, sizeof (uint64_t), 1, 94 &spa->spa_history, tx) == 0); 95 96 VERIFY(0 == dmu_bonus_hold(mos, spa->spa_history, FTAG, &dbp)); 97 ASSERT(dbp->db_size >= sizeof (spa_history_phys_t)); 98 99 shpp = dbp->db_data; 100 dmu_buf_will_dirty(dbp, tx); 101 102 /* 103 * Figure out maximum size of history log. We set it at 104 * 1% of pool size, with a max of 32MB and min of 128KB. 105 */ 106 shpp->sh_phys_max_off = 107 metaslab_class_get_dspace(spa_normal_class(spa)) / 100; 108 shpp->sh_phys_max_off = MIN(shpp->sh_phys_max_off, 32<<20); 109 shpp->sh_phys_max_off = MAX(shpp->sh_phys_max_off, 128<<10); 110 111 dmu_buf_rele(dbp, FTAG); 112 } 113 114 /* 115 * Change 'sh_bof' to the beginning of the next record. 116 */ 117 static int 118 spa_history_advance_bof(spa_t *spa, spa_history_phys_t *shpp) 119 { 120 objset_t *mos = spa->spa_meta_objset; 121 uint64_t firstread, reclen, phys_bof; 122 char buf[sizeof (reclen)]; 123 int err; 124 125 phys_bof = spa_history_log_to_phys(shpp->sh_bof, shpp); 126 firstread = MIN(sizeof (reclen), shpp->sh_phys_max_off - phys_bof); 127 128 if ((err = dmu_read(mos, spa->spa_history, phys_bof, firstread, 129 buf, DMU_READ_PREFETCH)) != 0) 130 return (err); 131 if (firstread != sizeof (reclen)) { 132 if ((err = dmu_read(mos, spa->spa_history, 133 shpp->sh_pool_create_len, sizeof (reclen) - firstread, 134 buf + firstread, DMU_READ_PREFETCH)) != 0) 135 return (err); 136 } 137 138 reclen = LE_64(*((uint64_t *)buf)); 139 shpp->sh_bof += reclen + sizeof (reclen); 140 shpp->sh_records_lost++; 141 return (0); 142 } 143 144 static int 145 spa_history_write(spa_t *spa, void *buf, uint64_t len, spa_history_phys_t *shpp, 146 dmu_tx_t *tx) 147 { 148 uint64_t firstwrite, phys_eof; 149 objset_t *mos = spa->spa_meta_objset; 150 int err; 151 152 ASSERT(MUTEX_HELD(&spa->spa_history_lock)); 153 154 /* see if we need to reset logical BOF */ 155 while (shpp->sh_phys_max_off - shpp->sh_pool_create_len - 156 (shpp->sh_eof - shpp->sh_bof) <= len) { 157 if ((err = spa_history_advance_bof(spa, shpp)) != 0) { 158 return (err); 159 } 160 } 161 162 phys_eof = spa_history_log_to_phys(shpp->sh_eof, shpp); 163 firstwrite = MIN(len, shpp->sh_phys_max_off - phys_eof); 164 shpp->sh_eof += len; 165 dmu_write(mos, spa->spa_history, phys_eof, firstwrite, buf, tx); 166 167 len -= firstwrite; 168 if (len > 0) { 169 /* write out the rest at the beginning of physical file */ 170 dmu_write(mos, spa->spa_history, shpp->sh_pool_create_len, 171 len, (char *)buf + firstwrite, tx); 172 } 173 174 return (0); 175 } 176 177 static char * 178 spa_history_zone() 179 { 180 #ifdef _KERNEL 181 return (curproc->p_zone->zone_name); 182 #else 183 return ("global"); 184 #endif 185 } 186 187 /* 188 * Write out a history event. 189 */ 190 /*ARGSUSED*/ 191 static void 192 spa_history_log_sync(void *arg1, void *arg2, cred_t *cr, dmu_tx_t *tx) 193 { 194 spa_t *spa = arg1; 195 history_arg_t *hap = arg2; 196 const char *history_str = hap->ha_history_str; 197 objset_t *mos = spa->spa_meta_objset; 198 dmu_buf_t *dbp; 199 spa_history_phys_t *shpp; 200 size_t reclen; 201 uint64_t le_len; 202 nvlist_t *nvrecord; 203 char *record_packed = NULL; 204 int ret; 205 206 /* 207 * If we have an older pool that doesn't have a command 208 * history object, create it now. 209 */ 210 mutex_enter(&spa->spa_history_lock); 211 if (!spa->spa_history) 212 spa_history_create_obj(spa, tx); 213 mutex_exit(&spa->spa_history_lock); 214 215 /* 216 * Get the offset of where we need to write via the bonus buffer. 217 * Update the offset when the write completes. 218 */ 219 VERIFY(0 == dmu_bonus_hold(mos, spa->spa_history, FTAG, &dbp)); 220 shpp = dbp->db_data; 221 222 dmu_buf_will_dirty(dbp, tx); 223 224 #ifdef ZFS_DEBUG 225 { 226 dmu_object_info_t doi; 227 dmu_object_info_from_db(dbp, &doi); 228 ASSERT3U(doi.doi_bonus_type, ==, DMU_OT_SPA_HISTORY_OFFSETS); 229 } 230 #endif 231 232 VERIFY(nvlist_alloc(&nvrecord, NV_UNIQUE_NAME, KM_SLEEP) == 0); 233 VERIFY(nvlist_add_uint64(nvrecord, ZPOOL_HIST_TIME, 234 gethrestime_sec()) == 0); 235 VERIFY(nvlist_add_uint64(nvrecord, ZPOOL_HIST_WHO, hap->ha_uid) == 0); 236 if (hap->ha_zone != NULL) 237 VERIFY(nvlist_add_string(nvrecord, ZPOOL_HIST_ZONE, 238 hap->ha_zone) == 0); 239 #ifdef _KERNEL 240 VERIFY(nvlist_add_string(nvrecord, ZPOOL_HIST_HOST, 241 utsname.nodename) == 0); 242 #endif 243 if (hap->ha_log_type == LOG_CMD_POOL_CREATE || 244 hap->ha_log_type == LOG_CMD_NORMAL) { 245 VERIFY(nvlist_add_string(nvrecord, ZPOOL_HIST_CMD, 246 history_str) == 0); 247 } else { 248 VERIFY(nvlist_add_uint64(nvrecord, ZPOOL_HIST_INT_EVENT, 249 hap->ha_event) == 0); 250 VERIFY(nvlist_add_uint64(nvrecord, ZPOOL_HIST_TXG, 251 tx->tx_txg) == 0); 252 VERIFY(nvlist_add_string(nvrecord, ZPOOL_HIST_INT_STR, 253 history_str) == 0); 254 } 255 256 VERIFY(nvlist_size(nvrecord, &reclen, NV_ENCODE_XDR) == 0); 257 record_packed = kmem_alloc(reclen, KM_SLEEP); 258 259 VERIFY(nvlist_pack(nvrecord, &record_packed, &reclen, 260 NV_ENCODE_XDR, KM_SLEEP) == 0); 261 262 mutex_enter(&spa->spa_history_lock); 263 if (hap->ha_log_type == LOG_CMD_POOL_CREATE) 264 VERIFY(shpp->sh_eof == shpp->sh_pool_create_len); 265 266 /* write out the packed length as little endian */ 267 le_len = LE_64((uint64_t)reclen); 268 ret = spa_history_write(spa, &le_len, sizeof (le_len), shpp, tx); 269 if (!ret) 270 ret = spa_history_write(spa, record_packed, reclen, shpp, tx); 271 272 if (!ret && hap->ha_log_type == LOG_CMD_POOL_CREATE) { 273 shpp->sh_pool_create_len += sizeof (le_len) + reclen; 274 shpp->sh_bof = shpp->sh_pool_create_len; 275 } 276 277 mutex_exit(&spa->spa_history_lock); 278 nvlist_free(nvrecord); 279 kmem_free(record_packed, reclen); 280 dmu_buf_rele(dbp, FTAG); 281 282 strfree(hap->ha_history_str); 283 if (hap->ha_zone != NULL) 284 strfree(hap->ha_zone); 285 kmem_free(hap, sizeof (history_arg_t)); 286 } 287 288 /* 289 * Write out a history event. 290 */ 291 int 292 spa_history_log(spa_t *spa, const char *history_str, history_log_type_t what) 293 { 294 history_arg_t *ha; 295 int err = 0; 296 dmu_tx_t *tx; 297 298 ASSERT(what != LOG_INTERNAL); 299 300 tx = dmu_tx_create_dd(spa_get_dsl(spa)->dp_mos_dir); 301 err = dmu_tx_assign(tx, TXG_WAIT); 302 if (err) { 303 dmu_tx_abort(tx); 304 return (err); 305 } 306 307 ha = kmem_alloc(sizeof (history_arg_t), KM_SLEEP); 308 ha->ha_history_str = strdup(history_str); 309 ha->ha_zone = strdup(spa_history_zone()); 310 ha->ha_log_type = what; 311 ha->ha_uid = crgetuid(CRED()); 312 313 /* Kick this off asynchronously; errors are ignored. */ 314 dsl_sync_task_do_nowait(spa_get_dsl(spa), NULL, 315 spa_history_log_sync, spa, ha, 0, tx); 316 dmu_tx_commit(tx); 317 318 /* spa_history_log_sync will free ha and strings */ 319 return (err); 320 } 321 322 /* 323 * Read out the command history. 324 */ 325 int 326 spa_history_get(spa_t *spa, uint64_t *offp, uint64_t *len, char *buf) 327 { 328 objset_t *mos = spa->spa_meta_objset; 329 dmu_buf_t *dbp; 330 uint64_t read_len, phys_read_off, phys_eof; 331 uint64_t leftover = 0; 332 spa_history_phys_t *shpp; 333 int err; 334 335 /* 336 * If the command history doesn't exist (older pool), 337 * that's ok, just return ENOENT. 338 */ 339 if (!spa->spa_history) 340 return (ENOENT); 341 342 /* 343 * The history is logged asynchronously, so when they request 344 * the first chunk of history, make sure everything has been 345 * synced to disk so that we get it. 346 */ 347 if (*offp == 0 && spa_writeable(spa)) 348 txg_wait_synced(spa_get_dsl(spa), 0); 349 350 if ((err = dmu_bonus_hold(mos, spa->spa_history, FTAG, &dbp)) != 0) 351 return (err); 352 shpp = dbp->db_data; 353 354 #ifdef ZFS_DEBUG 355 { 356 dmu_object_info_t doi; 357 dmu_object_info_from_db(dbp, &doi); 358 ASSERT3U(doi.doi_bonus_type, ==, DMU_OT_SPA_HISTORY_OFFSETS); 359 } 360 #endif 361 362 mutex_enter(&spa->spa_history_lock); 363 phys_eof = spa_history_log_to_phys(shpp->sh_eof, shpp); 364 365 if (*offp < shpp->sh_pool_create_len) { 366 /* read in just the zpool create history */ 367 phys_read_off = *offp; 368 read_len = MIN(*len, shpp->sh_pool_create_len - 369 phys_read_off); 370 } else { 371 /* 372 * Need to reset passed in offset to BOF if the passed in 373 * offset has since been overwritten. 374 */ 375 *offp = MAX(*offp, shpp->sh_bof); 376 phys_read_off = spa_history_log_to_phys(*offp, shpp); 377 378 /* 379 * Read up to the minimum of what the user passed down or 380 * the EOF (physical or logical). If we hit physical EOF, 381 * use 'leftover' to read from the physical BOF. 382 */ 383 if (phys_read_off <= phys_eof) { 384 read_len = MIN(*len, phys_eof - phys_read_off); 385 } else { 386 read_len = MIN(*len, 387 shpp->sh_phys_max_off - phys_read_off); 388 if (phys_read_off + *len > shpp->sh_phys_max_off) { 389 leftover = MIN(*len - read_len, 390 phys_eof - shpp->sh_pool_create_len); 391 } 392 } 393 } 394 395 /* offset for consumer to use next */ 396 *offp += read_len + leftover; 397 398 /* tell the consumer how much you actually read */ 399 *len = read_len + leftover; 400 401 if (read_len == 0) { 402 mutex_exit(&spa->spa_history_lock); 403 dmu_buf_rele(dbp, FTAG); 404 return (0); 405 } 406 407 err = dmu_read(mos, spa->spa_history, phys_read_off, read_len, buf, 408 DMU_READ_PREFETCH); 409 if (leftover && err == 0) { 410 err = dmu_read(mos, spa->spa_history, shpp->sh_pool_create_len, 411 leftover, buf + read_len, DMU_READ_PREFETCH); 412 } 413 mutex_exit(&spa->spa_history_lock); 414 415 dmu_buf_rele(dbp, FTAG); 416 return (err); 417 } 418 419 static void 420 log_internal(history_internal_events_t event, spa_t *spa, 421 dmu_tx_t *tx, cred_t *cr, const char *fmt, va_list adx) 422 { 423 history_arg_t *ha; 424 425 /* 426 * If this is part of creating a pool, not everything is 427 * initialized yet, so don't bother logging the internal events. 428 */ 429 if (tx->tx_txg == TXG_INITIAL) 430 return; 431 432 ha = kmem_alloc(sizeof (history_arg_t), KM_SLEEP); 433 ha->ha_history_str = kmem_alloc(vsnprintf(NULL, 0, fmt, adx) + 1, 434 KM_SLEEP); 435 436 (void) vsprintf(ha->ha_history_str, fmt, adx); 437 438 ha->ha_log_type = LOG_INTERNAL; 439 ha->ha_event = event; 440 ha->ha_zone = NULL; 441 ha->ha_uid = 0; 442 443 if (dmu_tx_is_syncing(tx)) { 444 spa_history_log_sync(spa, ha, cr, tx); 445 } else { 446 dsl_sync_task_do_nowait(spa_get_dsl(spa), NULL, 447 spa_history_log_sync, spa, ha, 0, tx); 448 } 449 /* spa_history_log_sync() will free ha and strings */ 450 } 451 452 void 453 spa_history_internal_log(history_internal_events_t event, spa_t *spa, 454 dmu_tx_t *tx, cred_t *cr, const char *fmt, ...) 455 { 456 dmu_tx_t *htx = tx; 457 va_list adx; 458 459 /* create a tx if we didn't get one */ 460 if (tx == NULL) { 461 htx = dmu_tx_create_dd(spa_get_dsl(spa)->dp_mos_dir); 462 if (dmu_tx_assign(htx, TXG_WAIT) != 0) { 463 dmu_tx_abort(htx); 464 return; 465 } 466 } 467 468 va_start(adx, fmt); 469 log_internal(event, spa, htx, cr, fmt, adx); 470 va_end(adx); 471 472 /* if we didn't get a tx from the caller, commit the one we made */ 473 if (tx == NULL) 474 dmu_tx_commit(htx); 475 } 476 477 void 478 spa_history_log_version(spa_t *spa, history_internal_events_t event) 479 { 480 #ifdef _KERNEL 481 uint64_t current_vers = spa_version(spa); 482 483 if (current_vers >= SPA_VERSION_ZPOOL_HISTORY) { 484 spa_history_internal_log(event, spa, NULL, CRED(), 485 "pool spa %llu; zfs spa %llu; zpl %d; uts %s %s %s %s", 486 (u_longlong_t)current_vers, SPA_VERSION, ZPL_VERSION, 487 utsname.nodename, utsname.release, utsname.version, 488 utsname.machine); 489 } 490 cmn_err(CE_CONT, "!%s version %llu pool %s using %llu", 491 event == LOG_POOL_IMPORT ? "imported" : 492 event == LOG_POOL_CREATE ? "created" : "accessed", 493 (u_longlong_t)current_vers, spa_name(spa), SPA_VERSION); 494 #endif 495 } 496