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 2009 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
spa_history_log_to_phys(uint64_t log_off,spa_history_phys_t * shpp)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
spa_history_create_obj(spa_t * spa,dmu_tx_t * tx)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
spa_history_advance_bof(spa_t * spa,spa_history_phys_t * shpp)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
spa_history_write(spa_t * spa,void * buf,uint64_t len,spa_history_phys_t * shpp,dmu_tx_t * tx)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 *
spa_history_zone()178 spa_history_zone()
179 {
180 #if defined(_KERNEL) && !defined(__NetBSD__)
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 static void
spa_history_log_sync(void * arg1,void * arg2,cred_t * cr,dmu_tx_t * tx)191 spa_history_log_sync(void *arg1, void *arg2, cred_t *cr, dmu_tx_t *tx)
192 {
193 spa_t *spa = arg1;
194 history_arg_t *hap = arg2;
195 const char *history_str = hap->ha_history_str;
196 objset_t *mos = spa->spa_meta_objset;
197 dmu_buf_t *dbp;
198 spa_history_phys_t *shpp;
199 size_t reclen;
200 uint64_t le_len;
201 nvlist_t *nvrecord;
202 char *record_packed = NULL;
203 int ret;
204
205 /*
206 * If we have an older pool that doesn't have a command
207 * history object, create it now.
208 */
209 mutex_enter(&spa->spa_history_lock);
210 if (!spa->spa_history)
211 spa_history_create_obj(spa, tx);
212 mutex_exit(&spa->spa_history_lock);
213
214 /*
215 * Get the offset of where we need to write via the bonus buffer.
216 * Update the offset when the write completes.
217 */
218 VERIFY(0 == dmu_bonus_hold(mos, spa->spa_history, FTAG, &dbp));
219 shpp = dbp->db_data;
220
221 dmu_buf_will_dirty(dbp, tx);
222
223 #ifdef ZFS_DEBUG
224 {
225 dmu_object_info_t doi;
226 dmu_object_info_from_db(dbp, &doi);
227 ASSERT3U(doi.doi_bonus_type, ==, DMU_OT_SPA_HISTORY_OFFSETS);
228 }
229 #endif
230
231 VERIFY(nvlist_alloc(&nvrecord, NV_UNIQUE_NAME, KM_SLEEP) == 0);
232 VERIFY(nvlist_add_uint64(nvrecord, ZPOOL_HIST_TIME,
233 gethrestime_sec()) == 0);
234 VERIFY(nvlist_add_uint64(nvrecord, ZPOOL_HIST_WHO,
235 (uint64_t)crgetuid(cr)) == 0);
236 if (hap->ha_zone[0] != '\0')
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 if (hap->ha_log_type == LOG_INTERNAL) {
283 kmem_free((void*)hap->ha_history_str, HIS_MAX_RECORD_LEN);
284 kmem_free(hap, sizeof (history_arg_t));
285 }
286 }
287
288 /*
289 * Write out a history event.
290 */
291 int
spa_history_log(spa_t * spa,const char * history_str,history_log_type_t what)292 spa_history_log(spa_t *spa, const char *history_str, history_log_type_t what)
293 {
294 history_arg_t ha;
295
296 ASSERT(what != LOG_INTERNAL);
297
298 ha.ha_history_str = history_str;
299 ha.ha_log_type = what;
300 (void) strlcpy(ha.ha_zone, spa_history_zone(), sizeof (ha.ha_zone));
301 return (dsl_sync_task_do(spa_get_dsl(spa), NULL, spa_history_log_sync,
302 spa, &ha, 0));
303 }
304
305 /*
306 * Read out the command history.
307 */
308 int
spa_history_get(spa_t * spa,uint64_t * offp,uint64_t * len,char * buf)309 spa_history_get(spa_t *spa, uint64_t *offp, uint64_t *len, char *buf)
310 {
311 objset_t *mos = spa->spa_meta_objset;
312 dmu_buf_t *dbp;
313 uint64_t read_len, phys_read_off, phys_eof;
314 uint64_t leftover = 0;
315 spa_history_phys_t *shpp;
316 int err;
317
318 /*
319 * If the command history doesn't exist (older pool),
320 * that's ok, just return ENOENT.
321 */
322 if (!spa->spa_history)
323 return (ENOENT);
324
325 if ((err = dmu_bonus_hold(mos, spa->spa_history, FTAG, &dbp)) != 0)
326 return (err);
327 shpp = dbp->db_data;
328
329 #ifdef ZFS_DEBUG
330 {
331 dmu_object_info_t doi;
332 dmu_object_info_from_db(dbp, &doi);
333 ASSERT3U(doi.doi_bonus_type, ==, DMU_OT_SPA_HISTORY_OFFSETS);
334 }
335 #endif
336
337 mutex_enter(&spa->spa_history_lock);
338 phys_eof = spa_history_log_to_phys(shpp->sh_eof, shpp);
339
340 if (*offp < shpp->sh_pool_create_len) {
341 /* read in just the zpool create history */
342 phys_read_off = *offp;
343 read_len = MIN(*len, shpp->sh_pool_create_len -
344 phys_read_off);
345 } else {
346 /*
347 * Need to reset passed in offset to BOF if the passed in
348 * offset has since been overwritten.
349 */
350 *offp = MAX(*offp, shpp->sh_bof);
351 phys_read_off = spa_history_log_to_phys(*offp, shpp);
352
353 /*
354 * Read up to the minimum of what the user passed down or
355 * the EOF (physical or logical). If we hit physical EOF,
356 * use 'leftover' to read from the physical BOF.
357 */
358 if (phys_read_off <= phys_eof) {
359 read_len = MIN(*len, phys_eof - phys_read_off);
360 } else {
361 read_len = MIN(*len,
362 shpp->sh_phys_max_off - phys_read_off);
363 if (phys_read_off + *len > shpp->sh_phys_max_off) {
364 leftover = MIN(*len - read_len,
365 phys_eof - shpp->sh_pool_create_len);
366 }
367 }
368 }
369
370 /* offset for consumer to use next */
371 *offp += read_len + leftover;
372
373 /* tell the consumer how much you actually read */
374 *len = read_len + leftover;
375
376 if (read_len == 0) {
377 mutex_exit(&spa->spa_history_lock);
378 dmu_buf_rele(dbp, FTAG);
379 return (0);
380 }
381
382 err = dmu_read(mos, spa->spa_history, phys_read_off, read_len, buf,
383 DMU_READ_PREFETCH);
384 if (leftover && err == 0) {
385 err = dmu_read(mos, spa->spa_history, shpp->sh_pool_create_len,
386 leftover, buf + read_len, DMU_READ_PREFETCH);
387 }
388 mutex_exit(&spa->spa_history_lock);
389
390 dmu_buf_rele(dbp, FTAG);
391 return (err);
392 }
393
394 static void
log_internal(history_internal_events_t event,spa_t * spa,dmu_tx_t * tx,cred_t * cr,const char * fmt,va_list adx)395 log_internal(history_internal_events_t event, spa_t *spa,
396 dmu_tx_t *tx, cred_t *cr, const char *fmt, va_list adx)
397 {
398 history_arg_t *hap;
399 char *str;
400
401 /*
402 * If this is part of creating a pool, not everything is
403 * initialized yet, so don't bother logging the internal events.
404 */
405 if (tx->tx_txg == TXG_INITIAL)
406 return;
407
408 hap = kmem_alloc(sizeof (history_arg_t), KM_SLEEP);
409 str = kmem_alloc(HIS_MAX_RECORD_LEN, KM_SLEEP);
410
411 (void) vsnprintf(str, HIS_MAX_RECORD_LEN, fmt, adx);
412
413 hap->ha_log_type = LOG_INTERNAL;
414 hap->ha_history_str = str;
415 hap->ha_event = event;
416 hap->ha_zone[0] = '\0';
417
418 if (dmu_tx_is_syncing(tx)) {
419 spa_history_log_sync(spa, hap, cr, tx);
420 } else {
421 dsl_sync_task_do_nowait(spa_get_dsl(spa), NULL,
422 spa_history_log_sync, spa, hap, 0, tx);
423 }
424 /* spa_history_log_sync() will free hap and str */
425 }
426
427 void
spa_history_internal_log(history_internal_events_t event,spa_t * spa,dmu_tx_t * tx,cred_t * cr,const char * fmt,...)428 spa_history_internal_log(history_internal_events_t event, spa_t *spa,
429 dmu_tx_t *tx, cred_t *cr, const char *fmt, ...)
430 {
431 dmu_tx_t *htx = tx;
432 va_list adx;
433
434 /* create a tx if we didn't get one */
435 if (tx == NULL) {
436 htx = dmu_tx_create_dd(spa_get_dsl(spa)->dp_mos_dir);
437 if (dmu_tx_assign(htx, TXG_WAIT) != 0) {
438 dmu_tx_abort(htx);
439 return;
440 }
441 }
442
443 va_start(adx, fmt);
444 log_internal(event, spa, htx, cr, fmt, adx);
445 va_end(adx);
446
447 /* if we didn't get a tx from the caller, commit the one we made */
448 if (tx == NULL)
449 dmu_tx_commit(htx);
450 }
451
452 void
spa_history_log_version(spa_t * spa,history_internal_events_t event)453 spa_history_log_version(spa_t *spa, history_internal_events_t event)
454 {
455 #ifdef _KERNEL
456 uint64_t current_vers = spa_version(spa);
457
458 if (current_vers >= SPA_VERSION_ZPOOL_HISTORY) {
459 spa_history_internal_log(event, spa, NULL, CRED(),
460 "pool spa %llu; zfs spa %llu; zpl %d; uts %s %s %s %s",
461 (u_longlong_t)current_vers, SPA_VERSION, ZPL_VERSION,
462 utsname.nodename, utsname.release, utsname.version,
463 utsname.machine);
464 }
465 cmn_err(CE_CONT, "!%s version %llu pool %s using %llu",
466 event == LOG_POOL_IMPORT ? "imported" :
467 event == LOG_POOL_CREATE ? "created" : "accessed",
468 (u_longlong_t)current_vers, spa_name(spa), SPA_VERSION);
469 #endif
470 }
471