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 2010 Sun Microsystems, Inc. All rights reserved.
23 * Use is subject to license terms.
24 */
25
26 #include <sys/dsl_pool.h>
27 #include <sys/dsl_dataset.h>
28 #include <sys/dsl_dir.h>
29 #include <sys/dsl_synctask.h>
30 #include <sys/dmu_tx.h>
31 #include <sys/dmu_objset.h>
32 #include <sys/arc.h>
33 #include <sys/zap.h>
34 #include <sys/zio.h>
35 #include <sys/zfs_context.h>
36 #include <sys/fs/zfs.h>
37 #include <sys/zfs_znode.h>
38 #include <sys/spa_impl.h>
39
40 int zfs_no_write_throttle = 0;
41 int zfs_write_limit_shift = 3; /* 1/8th of physical memory */
42 int zfs_txg_synctime_ms = 5000; /* target millisecs to sync a txg */
43
44 uint64_t zfs_write_limit_min = 32 << 20; /* min write limit is 32MB */
45 uint64_t zfs_write_limit_max = 0; /* max data payload per txg */
46 uint64_t zfs_write_limit_inflated = 0;
47 uint64_t zfs_write_limit_override = 0;
48
49 kmutex_t zfs_write_limit_lock;
50
51 static pgcnt_t old_physmem = 0;
52
53 static int
dsl_pool_open_special_dir(dsl_pool_t * dp,const char * name,dsl_dir_t ** ddp)54 dsl_pool_open_special_dir(dsl_pool_t *dp, const char *name, dsl_dir_t **ddp)
55 {
56 uint64_t obj;
57 int err;
58
59 err = zap_lookup(dp->dp_meta_objset,
60 dp->dp_root_dir->dd_phys->dd_child_dir_zapobj,
61 name, sizeof (obj), 1, &obj);
62 if (err)
63 return (err);
64
65 return (dsl_dir_open_obj(dp, obj, name, dp, ddp));
66 }
67
68 static dsl_pool_t *
dsl_pool_open_impl(spa_t * spa,uint64_t txg)69 dsl_pool_open_impl(spa_t *spa, uint64_t txg)
70 {
71 dsl_pool_t *dp;
72 blkptr_t *bp = spa_get_rootblkptr(spa);
73
74 dp = kmem_zalloc(sizeof (dsl_pool_t), KM_SLEEP);
75 dp->dp_spa = spa;
76 dp->dp_meta_rootbp = *bp;
77 rw_init(&dp->dp_config_rwlock, NULL, RW_DEFAULT, NULL);
78 dp->dp_write_limit = zfs_write_limit_min;
79 txg_init(dp, txg);
80
81 txg_list_create(&dp->dp_dirty_datasets,
82 offsetof(dsl_dataset_t, ds_dirty_link));
83 txg_list_create(&dp->dp_dirty_dirs,
84 offsetof(dsl_dir_t, dd_dirty_link));
85 txg_list_create(&dp->dp_sync_tasks,
86 offsetof(dsl_sync_task_group_t, dstg_node));
87 list_create(&dp->dp_synced_datasets, sizeof (dsl_dataset_t),
88 offsetof(dsl_dataset_t, ds_synced_link));
89
90 mutex_init(&dp->dp_lock, NULL, MUTEX_DEFAULT, NULL);
91 mutex_init(&dp->dp_scrub_cancel_lock, NULL, MUTEX_DEFAULT, NULL);
92
93 dp->dp_vnrele_taskq = taskq_create("zfs_vn_rele_taskq", 1, minclsyspri,
94 1, 4, 0);
95
96 return (dp);
97 }
98
99 int
dsl_pool_open(spa_t * spa,uint64_t txg,dsl_pool_t ** dpp)100 dsl_pool_open(spa_t *spa, uint64_t txg, dsl_pool_t **dpp)
101 {
102 int err;
103 dsl_pool_t *dp = dsl_pool_open_impl(spa, txg);
104 dsl_dir_t *dd;
105 dsl_dataset_t *ds;
106
107 rw_enter(&dp->dp_config_rwlock, RW_WRITER);
108 err = dmu_objset_open_impl(spa, NULL, &dp->dp_meta_rootbp,
109 &dp->dp_meta_objset);
110 if (err)
111 goto out;
112
113 err = zap_lookup(dp->dp_meta_objset, DMU_POOL_DIRECTORY_OBJECT,
114 DMU_POOL_ROOT_DATASET, sizeof (uint64_t), 1,
115 &dp->dp_root_dir_obj);
116 if (err)
117 goto out;
118
119 err = dsl_dir_open_obj(dp, dp->dp_root_dir_obj,
120 NULL, dp, &dp->dp_root_dir);
121 if (err)
122 goto out;
123
124 err = dsl_pool_open_special_dir(dp, MOS_DIR_NAME, &dp->dp_mos_dir);
125 if (err)
126 goto out;
127
128 if (spa_version(spa) >= SPA_VERSION_ORIGIN) {
129 err = dsl_pool_open_special_dir(dp, ORIGIN_DIR_NAME, &dd);
130 if (err)
131 goto out;
132 err = dsl_dataset_hold_obj(dp, dd->dd_phys->dd_head_dataset_obj,
133 FTAG, &ds);
134 if (err == 0) {
135 err = dsl_dataset_hold_obj(dp,
136 ds->ds_phys->ds_prev_snap_obj, dp,
137 &dp->dp_origin_snap);
138 dsl_dataset_rele(ds, FTAG);
139 }
140 dsl_dir_close(dd, dp);
141 if (err)
142 goto out;
143 }
144
145 err = zap_lookup(dp->dp_meta_objset, DMU_POOL_DIRECTORY_OBJECT,
146 DMU_POOL_TMP_USERREFS, sizeof (uint64_t), 1,
147 &dp->dp_tmp_userrefs_obj);
148 if (err == ENOENT)
149 err = 0;
150 if (err)
151 goto out;
152
153 /* get scrub status */
154 err = zap_lookup(dp->dp_meta_objset, DMU_POOL_DIRECTORY_OBJECT,
155 DMU_POOL_SCRUB_FUNC, sizeof (uint32_t), 1,
156 &dp->dp_scrub_func);
157 if (err == 0) {
158 err = zap_lookup(dp->dp_meta_objset, DMU_POOL_DIRECTORY_OBJECT,
159 DMU_POOL_SCRUB_QUEUE, sizeof (uint64_t), 1,
160 &dp->dp_scrub_queue_obj);
161 if (err)
162 goto out;
163 err = zap_lookup(dp->dp_meta_objset, DMU_POOL_DIRECTORY_OBJECT,
164 DMU_POOL_SCRUB_MIN_TXG, sizeof (uint64_t), 1,
165 &dp->dp_scrub_min_txg);
166 if (err)
167 goto out;
168 err = zap_lookup(dp->dp_meta_objset, DMU_POOL_DIRECTORY_OBJECT,
169 DMU_POOL_SCRUB_MAX_TXG, sizeof (uint64_t), 1,
170 &dp->dp_scrub_max_txg);
171 if (err)
172 goto out;
173 err = zap_lookup(dp->dp_meta_objset, DMU_POOL_DIRECTORY_OBJECT,
174 DMU_POOL_SCRUB_BOOKMARK, sizeof (uint64_t),
175 sizeof (dp->dp_scrub_bookmark) / sizeof (uint64_t),
176 &dp->dp_scrub_bookmark);
177 if (err)
178 goto out;
179 err = zap_lookup(dp->dp_meta_objset, DMU_POOL_DIRECTORY_OBJECT,
180 DMU_POOL_SCRUB_DDT_BOOKMARK, sizeof (uint64_t),
181 sizeof (dp->dp_scrub_ddt_bookmark) / sizeof (uint64_t),
182 &dp->dp_scrub_ddt_bookmark);
183 if (err && err != ENOENT)
184 goto out;
185 err = zap_lookup(dp->dp_meta_objset, DMU_POOL_DIRECTORY_OBJECT,
186 DMU_POOL_SCRUB_DDT_CLASS_MAX, sizeof (uint64_t), 1,
187 &dp->dp_scrub_ddt_class_max);
188 if (err && err != ENOENT)
189 goto out;
190 err = zap_lookup(dp->dp_meta_objset, DMU_POOL_DIRECTORY_OBJECT,
191 DMU_POOL_SCRUB_ERRORS, sizeof (uint64_t), 1,
192 &spa->spa_scrub_errors);
193 if (err)
194 goto out;
195 if (spa_version(spa) < SPA_VERSION_DSL_SCRUB) {
196 /*
197 * A new-type scrub was in progress on an old
198 * pool. Restart from the beginning, since the
199 * old software may have changed the pool in the
200 * meantime.
201 */
202 dsl_pool_scrub_restart(dp);
203 }
204 } else {
205 /*
206 * It's OK if there is no scrub in progress (and if
207 * there was an I/O error, ignore it).
208 */
209 err = 0;
210 }
211
212 out:
213 rw_exit(&dp->dp_config_rwlock);
214 if (err)
215 dsl_pool_close(dp);
216 else
217 *dpp = dp;
218
219 return (err);
220 }
221
222 void
dsl_pool_close(dsl_pool_t * dp)223 dsl_pool_close(dsl_pool_t *dp)
224 {
225 /* drop our references from dsl_pool_open() */
226
227 /*
228 * Since we held the origin_snap from "syncing" context (which
229 * includes pool-opening context), it actually only got a "ref"
230 * and not a hold, so just drop that here.
231 */
232 if (dp->dp_origin_snap)
233 dsl_dataset_drop_ref(dp->dp_origin_snap, dp);
234 if (dp->dp_mos_dir)
235 dsl_dir_close(dp->dp_mos_dir, dp);
236 if (dp->dp_root_dir)
237 dsl_dir_close(dp->dp_root_dir, dp);
238
239 /* undo the dmu_objset_open_impl(mos) from dsl_pool_open() */
240 if (dp->dp_meta_objset)
241 dmu_objset_evict(dp->dp_meta_objset);
242
243 txg_list_destroy(&dp->dp_dirty_datasets);
244 txg_list_destroy(&dp->dp_dirty_dirs);
245 txg_list_destroy(&dp->dp_sync_tasks);
246 list_destroy(&dp->dp_synced_datasets);
247
248 arc_flush(dp->dp_spa);
249 txg_fini(dp);
250 rw_destroy(&dp->dp_config_rwlock);
251 mutex_destroy(&dp->dp_lock);
252 mutex_destroy(&dp->dp_scrub_cancel_lock);
253 taskq_destroy(dp->dp_vnrele_taskq);
254 if (dp->dp_blkstats)
255 kmem_free(dp->dp_blkstats, sizeof (zfs_all_blkstats_t));
256 kmem_free(dp, sizeof (dsl_pool_t));
257 }
258
259 dsl_pool_t *
dsl_pool_create(spa_t * spa,nvlist_t * zplprops,uint64_t txg)260 dsl_pool_create(spa_t *spa, nvlist_t *zplprops, uint64_t txg)
261 {
262 int err;
263 dsl_pool_t *dp = dsl_pool_open_impl(spa, txg);
264 dmu_tx_t *tx = dmu_tx_create_assigned(dp, txg);
265 objset_t *os;
266 dsl_dataset_t *ds;
267 uint64_t dsobj;
268
269 /* create and open the MOS (meta-objset) */
270 dp->dp_meta_objset = dmu_objset_create_impl(spa,
271 NULL, &dp->dp_meta_rootbp, DMU_OST_META, tx);
272
273 /* create the pool directory */
274 err = zap_create_claim(dp->dp_meta_objset, DMU_POOL_DIRECTORY_OBJECT,
275 DMU_OT_OBJECT_DIRECTORY, DMU_OT_NONE, 0, tx);
276 ASSERT3U(err, ==, 0);
277
278 /* create and open the root dir */
279 dp->dp_root_dir_obj = dsl_dir_create_sync(dp, NULL, NULL, tx);
280 VERIFY(0 == dsl_dir_open_obj(dp, dp->dp_root_dir_obj,
281 NULL, dp, &dp->dp_root_dir));
282
283 /* create and open the meta-objset dir */
284 (void) dsl_dir_create_sync(dp, dp->dp_root_dir, MOS_DIR_NAME, tx);
285 VERIFY(0 == dsl_pool_open_special_dir(dp,
286 MOS_DIR_NAME, &dp->dp_mos_dir));
287
288 if (spa_version(spa) >= SPA_VERSION_DSL_SCRUB)
289 dsl_pool_create_origin(dp, tx);
290
291 /* create the root dataset */
292 dsobj = dsl_dataset_create_sync_dd(dp->dp_root_dir, NULL, 0, tx);
293
294 /* create the root objset */
295 VERIFY(0 == dsl_dataset_hold_obj(dp, dsobj, FTAG, &ds));
296 os = dmu_objset_create_impl(dp->dp_spa, ds,
297 dsl_dataset_get_blkptr(ds), DMU_OST_ZFS, tx);
298 #ifdef _KERNEL
299 zfs_create_fs(os, kcred, zplprops, tx);
300 #endif
301 dsl_dataset_rele(ds, FTAG);
302
303 dmu_tx_commit(tx);
304
305 return (dp);
306 }
307
308 void
dsl_pool_sync(dsl_pool_t * dp,uint64_t txg)309 dsl_pool_sync(dsl_pool_t *dp, uint64_t txg)
310 {
311 zio_t *zio;
312 dmu_tx_t *tx;
313 dsl_dir_t *dd;
314 dsl_dataset_t *ds;
315 dsl_sync_task_group_t *dstg;
316 objset_t *mos = dp->dp_meta_objset;
317 hrtime_t start, write_time;
318 uint64_t data_written;
319 int err;
320
321 tx = dmu_tx_create_assigned(dp, txg);
322
323 dp->dp_read_overhead = 0;
324 start = gethrtime();
325
326 zio = zio_root(dp->dp_spa, NULL, NULL, ZIO_FLAG_MUSTSUCCEED);
327 while (ds = txg_list_remove(&dp->dp_dirty_datasets, txg)) {
328 /*
329 * We must not sync any non-MOS datasets twice, because
330 * we may have taken a snapshot of them. However, we
331 * may sync newly-created datasets on pass 2.
332 */
333 ASSERT(!list_link_active(&ds->ds_synced_link));
334 list_insert_tail(&dp->dp_synced_datasets, ds);
335 dsl_dataset_sync(ds, zio, tx);
336 }
337 DTRACE_PROBE(pool_sync__1setup);
338 err = zio_wait(zio);
339
340 write_time = gethrtime() - start;
341 ASSERT(err == 0);
342 DTRACE_PROBE(pool_sync__2rootzio);
343
344 for (ds = list_head(&dp->dp_synced_datasets); ds;
345 ds = list_next(&dp->dp_synced_datasets, ds))
346 dmu_objset_do_userquota_callbacks(ds->ds_objset, tx);
347
348 /*
349 * Sync the datasets again to push out the changes due to
350 * userquota updates. This must be done before we process the
351 * sync tasks, because that could cause a snapshot of a dataset
352 * whose ds_bp will be rewritten when we do this 2nd sync.
353 */
354 zio = zio_root(dp->dp_spa, NULL, NULL, ZIO_FLAG_MUSTSUCCEED);
355 while (ds = txg_list_remove(&dp->dp_dirty_datasets, txg)) {
356 ASSERT(list_link_active(&ds->ds_synced_link));
357 dmu_buf_rele(ds->ds_dbuf, ds);
358 dsl_dataset_sync(ds, zio, tx);
359 }
360 err = zio_wait(zio);
361
362 /*
363 * If anything was added to a deadlist during a zio done callback,
364 * it had to be put on the deferred queue. Enqueue it for real now.
365 */
366 for (ds = list_head(&dp->dp_synced_datasets); ds;
367 ds = list_next(&dp->dp_synced_datasets, ds))
368 bplist_sync(&ds->ds_deadlist,
369 bplist_enqueue_cb, &ds->ds_deadlist, tx);
370
371 while (dstg = txg_list_remove(&dp->dp_sync_tasks, txg)) {
372 /*
373 * No more sync tasks should have been added while we
374 * were syncing.
375 */
376 ASSERT(spa_sync_pass(dp->dp_spa) == 1);
377 dsl_sync_task_group_sync(dstg, tx);
378 }
379 DTRACE_PROBE(pool_sync__3task);
380
381 start = gethrtime();
382 while (dd = txg_list_remove(&dp->dp_dirty_dirs, txg))
383 dsl_dir_sync(dd, tx);
384 write_time += gethrtime() - start;
385
386 if (spa_sync_pass(dp->dp_spa) == 1) {
387 dp->dp_scrub_prefetch_zio_root = zio_root(dp->dp_spa, NULL,
388 NULL, ZIO_FLAG_CANFAIL);
389 dsl_pool_scrub_sync(dp, tx);
390 (void) zio_wait(dp->dp_scrub_prefetch_zio_root);
391 }
392
393 start = gethrtime();
394 if (list_head(&mos->os_dirty_dnodes[txg & TXG_MASK]) != NULL ||
395 list_head(&mos->os_free_dnodes[txg & TXG_MASK]) != NULL) {
396 zio = zio_root(dp->dp_spa, NULL, NULL, ZIO_FLAG_MUSTSUCCEED);
397 dmu_objset_sync(mos, zio, tx);
398 err = zio_wait(zio);
399 ASSERT(err == 0);
400 dprintf_bp(&dp->dp_meta_rootbp, "meta objset rootbp is %s", "");
401 spa_set_rootblkptr(dp->dp_spa, &dp->dp_meta_rootbp);
402 }
403 write_time += gethrtime() - start;
404 DTRACE_PROBE2(pool_sync__4io, hrtime_t, write_time,
405 hrtime_t, dp->dp_read_overhead);
406 write_time -= dp->dp_read_overhead;
407
408 dmu_tx_commit(tx);
409
410 data_written = dp->dp_space_towrite[txg & TXG_MASK];
411 dp->dp_space_towrite[txg & TXG_MASK] = 0;
412 ASSERT(dp->dp_tempreserved[txg & TXG_MASK] == 0);
413
414 /*
415 * If the write limit max has not been explicitly set, set it
416 * to a fraction of available physical memory (default 1/8th).
417 * Note that we must inflate the limit because the spa
418 * inflates write sizes to account for data replication.
419 * Check this each sync phase to catch changing memory size.
420 */
421 if (physmem != old_physmem && zfs_write_limit_shift) {
422 mutex_enter(&zfs_write_limit_lock);
423 old_physmem = physmem;
424 zfs_write_limit_max = ptob(physmem) >> zfs_write_limit_shift;
425 zfs_write_limit_inflated = MAX(zfs_write_limit_min,
426 spa_get_asize(dp->dp_spa, zfs_write_limit_max));
427 mutex_exit(&zfs_write_limit_lock);
428 }
429
430 /*
431 * Attempt to keep the sync time consistent by adjusting the
432 * amount of write traffic allowed into each transaction group.
433 * Weight the throughput calculation towards the current value:
434 * thru = 3/4 old_thru + 1/4 new_thru
435 *
436 * Note: write_time is in nanosecs, so write_time/MICROSEC
437 * yields millisecs
438 */
439 ASSERT(zfs_write_limit_min > 0);
440 if (data_written > zfs_write_limit_min / 8 && write_time > MICROSEC) {
441 uint64_t throughput = data_written / (write_time / MICROSEC);
442
443 if (dp->dp_throughput)
444 dp->dp_throughput = throughput / 4 +
445 3 * dp->dp_throughput / 4;
446 else
447 dp->dp_throughput = throughput;
448 dp->dp_write_limit = MIN(zfs_write_limit_inflated,
449 MAX(zfs_write_limit_min,
450 dp->dp_throughput * zfs_txg_synctime_ms));
451 }
452 }
453
454 void
dsl_pool_sync_done(dsl_pool_t * dp,uint64_t txg)455 dsl_pool_sync_done(dsl_pool_t *dp, uint64_t txg)
456 {
457 dsl_dataset_t *ds;
458 objset_t *os;
459
460 while (ds = list_head(&dp->dp_synced_datasets)) {
461 list_remove(&dp->dp_synced_datasets, ds);
462 os = ds->ds_objset;
463 zil_clean(os->os_zil);
464 ASSERT(!dmu_objset_is_dirty(os, txg));
465 dmu_buf_rele(ds->ds_dbuf, ds);
466 }
467 ASSERT(!dmu_objset_is_dirty(dp->dp_meta_objset, txg));
468 }
469
470 /*
471 * TRUE if the current thread is the tx_sync_thread or if we
472 * are being called from SPA context during pool initialization.
473 */
474 int
dsl_pool_sync_context(dsl_pool_t * dp)475 dsl_pool_sync_context(dsl_pool_t *dp)
476 {
477 return (curthread == dp->dp_tx.tx_sync_thread ||
478 spa_get_dsl(dp->dp_spa) == NULL);
479 }
480
481 uint64_t
dsl_pool_adjustedsize(dsl_pool_t * dp,boolean_t netfree)482 dsl_pool_adjustedsize(dsl_pool_t *dp, boolean_t netfree)
483 {
484 uint64_t space, resv;
485
486 /*
487 * Reserve about 1.6% (1/64), or at least 32MB, for allocation
488 * efficiency.
489 * XXX The intent log is not accounted for, so it must fit
490 * within this slop.
491 *
492 * If we're trying to assess whether it's OK to do a free,
493 * cut the reservation in half to allow forward progress
494 * (e.g. make it possible to rm(1) files from a full pool).
495 */
496 space = spa_get_dspace(dp->dp_spa);
497 resv = MAX(space >> 6, SPA_MINDEVSIZE >> 1);
498 if (netfree)
499 resv >>= 1;
500
501 return (space - resv);
502 }
503
504 int
dsl_pool_tempreserve_space(dsl_pool_t * dp,uint64_t space,dmu_tx_t * tx)505 dsl_pool_tempreserve_space(dsl_pool_t *dp, uint64_t space, dmu_tx_t *tx)
506 {
507 uint64_t reserved = 0;
508 uint64_t write_limit = (zfs_write_limit_override ?
509 zfs_write_limit_override : dp->dp_write_limit);
510
511 if (zfs_no_write_throttle) {
512 atomic_add_64(&dp->dp_tempreserved[tx->tx_txg & TXG_MASK],
513 space);
514 return (0);
515 }
516
517 /*
518 * Check to see if we have exceeded the maximum allowed IO for
519 * this transaction group. We can do this without locks since
520 * a little slop here is ok. Note that we do the reserved check
521 * with only half the requested reserve: this is because the
522 * reserve requests are worst-case, and we really don't want to
523 * throttle based off of worst-case estimates.
524 */
525 if (write_limit > 0) {
526 reserved = dp->dp_space_towrite[tx->tx_txg & TXG_MASK]
527 + dp->dp_tempreserved[tx->tx_txg & TXG_MASK] / 2;
528
529 if (reserved && reserved > write_limit)
530 return (ERESTART);
531 }
532
533 atomic_add_64(&dp->dp_tempreserved[tx->tx_txg & TXG_MASK], space);
534
535 /*
536 * If this transaction group is over 7/8ths capacity, delay
537 * the caller 1 clock tick. This will slow down the "fill"
538 * rate until the sync process can catch up with us.
539 */
540 if (reserved && reserved > (write_limit - (write_limit >> 3)))
541 txg_delay(dp, tx->tx_txg, 1);
542
543 return (0);
544 }
545
546 void
dsl_pool_tempreserve_clear(dsl_pool_t * dp,int64_t space,dmu_tx_t * tx)547 dsl_pool_tempreserve_clear(dsl_pool_t *dp, int64_t space, dmu_tx_t *tx)
548 {
549 ASSERT(dp->dp_tempreserved[tx->tx_txg & TXG_MASK] >= space);
550 atomic_add_64(&dp->dp_tempreserved[tx->tx_txg & TXG_MASK], -space);
551 }
552
553 void
dsl_pool_memory_pressure(dsl_pool_t * dp)554 dsl_pool_memory_pressure(dsl_pool_t *dp)
555 {
556 uint64_t space_inuse = 0;
557 int i;
558
559 if (dp->dp_write_limit == zfs_write_limit_min)
560 return;
561
562 for (i = 0; i < TXG_SIZE; i++) {
563 space_inuse += dp->dp_space_towrite[i];
564 space_inuse += dp->dp_tempreserved[i];
565 }
566 dp->dp_write_limit = MAX(zfs_write_limit_min,
567 MIN(dp->dp_write_limit, space_inuse / 4));
568 }
569
570 void
dsl_pool_willuse_space(dsl_pool_t * dp,int64_t space,dmu_tx_t * tx)571 dsl_pool_willuse_space(dsl_pool_t *dp, int64_t space, dmu_tx_t *tx)
572 {
573 if (space > 0) {
574 mutex_enter(&dp->dp_lock);
575 dp->dp_space_towrite[tx->tx_txg & TXG_MASK] += space;
576 mutex_exit(&dp->dp_lock);
577 }
578 }
579
580 /* ARGSUSED */
581 static int
upgrade_clones_cb(spa_t * spa,uint64_t dsobj,const char * dsname,void * arg)582 upgrade_clones_cb(spa_t *spa, uint64_t dsobj, const char *dsname, void *arg)
583 {
584 dmu_tx_t *tx = arg;
585 dsl_dataset_t *ds, *prev = NULL;
586 int err;
587 dsl_pool_t *dp = spa_get_dsl(spa);
588
589 err = dsl_dataset_hold_obj(dp, dsobj, FTAG, &ds);
590 if (err)
591 return (err);
592
593 while (ds->ds_phys->ds_prev_snap_obj != 0) {
594 err = dsl_dataset_hold_obj(dp, ds->ds_phys->ds_prev_snap_obj,
595 FTAG, &prev);
596 if (err) {
597 dsl_dataset_rele(ds, FTAG);
598 return (err);
599 }
600
601 if (prev->ds_phys->ds_next_snap_obj != ds->ds_object)
602 break;
603 dsl_dataset_rele(ds, FTAG);
604 ds = prev;
605 prev = NULL;
606 }
607
608 if (prev == NULL) {
609 prev = dp->dp_origin_snap;
610
611 /*
612 * The $ORIGIN can't have any data, or the accounting
613 * will be wrong.
614 */
615 ASSERT(prev->ds_phys->ds_bp.blk_birth == 0);
616
617 /* The origin doesn't get attached to itself */
618 if (ds->ds_object == prev->ds_object) {
619 dsl_dataset_rele(ds, FTAG);
620 return (0);
621 }
622
623 dmu_buf_will_dirty(ds->ds_dbuf, tx);
624 ds->ds_phys->ds_prev_snap_obj = prev->ds_object;
625 ds->ds_phys->ds_prev_snap_txg = prev->ds_phys->ds_creation_txg;
626
627 dmu_buf_will_dirty(ds->ds_dir->dd_dbuf, tx);
628 ds->ds_dir->dd_phys->dd_origin_obj = prev->ds_object;
629
630 dmu_buf_will_dirty(prev->ds_dbuf, tx);
631 prev->ds_phys->ds_num_children++;
632
633 if (ds->ds_phys->ds_next_snap_obj == 0) {
634 ASSERT(ds->ds_prev == NULL);
635 VERIFY(0 == dsl_dataset_hold_obj(dp,
636 ds->ds_phys->ds_prev_snap_obj, ds, &ds->ds_prev));
637 }
638 }
639
640 ASSERT(ds->ds_dir->dd_phys->dd_origin_obj == prev->ds_object);
641 ASSERT(ds->ds_phys->ds_prev_snap_obj == prev->ds_object);
642
643 if (prev->ds_phys->ds_next_clones_obj == 0) {
644 dmu_buf_will_dirty(prev->ds_dbuf, tx);
645 prev->ds_phys->ds_next_clones_obj =
646 zap_create(dp->dp_meta_objset,
647 DMU_OT_NEXT_CLONES, DMU_OT_NONE, 0, tx);
648 }
649 VERIFY(0 == zap_add_int(dp->dp_meta_objset,
650 prev->ds_phys->ds_next_clones_obj, ds->ds_object, tx));
651
652 dsl_dataset_rele(ds, FTAG);
653 if (prev != dp->dp_origin_snap)
654 dsl_dataset_rele(prev, FTAG);
655 return (0);
656 }
657
658 void
dsl_pool_upgrade_clones(dsl_pool_t * dp,dmu_tx_t * tx)659 dsl_pool_upgrade_clones(dsl_pool_t *dp, dmu_tx_t *tx)
660 {
661 ASSERT(dmu_tx_is_syncing(tx));
662 ASSERT(dp->dp_origin_snap != NULL);
663
664 VERIFY3U(0, ==, dmu_objset_find_spa(dp->dp_spa, NULL, upgrade_clones_cb,
665 tx, DS_FIND_CHILDREN));
666 }
667
668 void
dsl_pool_create_origin(dsl_pool_t * dp,dmu_tx_t * tx)669 dsl_pool_create_origin(dsl_pool_t *dp, dmu_tx_t *tx)
670 {
671 uint64_t dsobj;
672 dsl_dataset_t *ds;
673
674 ASSERT(dmu_tx_is_syncing(tx));
675 ASSERT(dp->dp_origin_snap == NULL);
676
677 /* create the origin dir, ds, & snap-ds */
678 rw_enter(&dp->dp_config_rwlock, RW_WRITER);
679 dsobj = dsl_dataset_create_sync(dp->dp_root_dir, ORIGIN_DIR_NAME,
680 NULL, 0, kcred, tx);
681 VERIFY(0 == dsl_dataset_hold_obj(dp, dsobj, FTAG, &ds));
682 dsl_dataset_snapshot_sync(ds, ORIGIN_DIR_NAME, kcred, tx);
683 VERIFY(0 == dsl_dataset_hold_obj(dp, ds->ds_phys->ds_prev_snap_obj,
684 dp, &dp->dp_origin_snap));
685 dsl_dataset_rele(ds, FTAG);
686 rw_exit(&dp->dp_config_rwlock);
687 }
688
689 taskq_t *
dsl_pool_vnrele_taskq(dsl_pool_t * dp)690 dsl_pool_vnrele_taskq(dsl_pool_t *dp)
691 {
692 return (dp->dp_vnrele_taskq);
693 }
694
695 /*
696 * Walk through the pool-wide zap object of temporary snapshot user holds
697 * and release them.
698 */
699 void
dsl_pool_clean_tmp_userrefs(dsl_pool_t * dp)700 dsl_pool_clean_tmp_userrefs(dsl_pool_t *dp)
701 {
702 zap_attribute_t za;
703 zap_cursor_t zc;
704 objset_t *mos = dp->dp_meta_objset;
705 uint64_t zapobj = dp->dp_tmp_userrefs_obj;
706
707 if (zapobj == 0)
708 return;
709 ASSERT(spa_version(dp->dp_spa) >= SPA_VERSION_USERREFS);
710
711 for (zap_cursor_init(&zc, mos, zapobj);
712 zap_cursor_retrieve(&zc, &za) == 0;
713 zap_cursor_advance(&zc)) {
714 char *htag;
715 uint64_t dsobj;
716
717 htag = strchr(za.za_name, '-');
718 *htag = '\0';
719 ++htag;
720 dsobj = strtonum(za.za_name, NULL);
721 (void) dsl_dataset_user_release_tmp(dp, dsobj, htag);
722 }
723 zap_cursor_fini(&zc);
724 }
725
726 /*
727 * Create the pool-wide zap object for storing temporary snapshot holds.
728 */
729 void
dsl_pool_user_hold_create_obj(dsl_pool_t * dp,dmu_tx_t * tx)730 dsl_pool_user_hold_create_obj(dsl_pool_t *dp, dmu_tx_t *tx)
731 {
732 objset_t *mos = dp->dp_meta_objset;
733
734 ASSERT(dp->dp_tmp_userrefs_obj == 0);
735 ASSERT(dmu_tx_is_syncing(tx));
736
737 dp->dp_tmp_userrefs_obj = zap_create(mos, DMU_OT_USERREFS,
738 DMU_OT_NONE, 0, tx);
739
740 VERIFY(zap_add(mos, DMU_POOL_DIRECTORY_OBJECT, DMU_POOL_TMP_USERREFS,
741 sizeof (uint64_t), 1, &dp->dp_tmp_userrefs_obj, tx) == 0);
742 }
743
744 static int
dsl_pool_user_hold_rele_impl(dsl_pool_t * dp,uint64_t dsobj,const char * tag,uint64_t * now,dmu_tx_t * tx,boolean_t holding)745 dsl_pool_user_hold_rele_impl(dsl_pool_t *dp, uint64_t dsobj,
746 const char *tag, uint64_t *now, dmu_tx_t *tx, boolean_t holding)
747 {
748 objset_t *mos = dp->dp_meta_objset;
749 uint64_t zapobj = dp->dp_tmp_userrefs_obj;
750 char *name;
751 int error;
752
753 ASSERT(spa_version(dp->dp_spa) >= SPA_VERSION_USERREFS);
754 ASSERT(dmu_tx_is_syncing(tx));
755
756 /*
757 * If the pool was created prior to SPA_VERSION_USERREFS, the
758 * zap object for temporary holds might not exist yet.
759 */
760 if (zapobj == 0) {
761 if (holding) {
762 dsl_pool_user_hold_create_obj(dp, tx);
763 zapobj = dp->dp_tmp_userrefs_obj;
764 } else {
765 return (ENOENT);
766 }
767 }
768
769 name = kmem_asprintf("%llx-%s", (u_longlong_t)dsobj, tag);
770 if (holding)
771 error = zap_add(mos, zapobj, name, 8, 1, now, tx);
772 else
773 error = zap_remove(mos, zapobj, name, tx);
774 strfree(name);
775
776 return (error);
777 }
778
779 /*
780 * Add a temporary hold for the given dataset object and tag.
781 */
782 int
dsl_pool_user_hold(dsl_pool_t * dp,uint64_t dsobj,const char * tag,uint64_t * now,dmu_tx_t * tx)783 dsl_pool_user_hold(dsl_pool_t *dp, uint64_t dsobj, const char *tag,
784 uint64_t *now, dmu_tx_t *tx)
785 {
786 return (dsl_pool_user_hold_rele_impl(dp, dsobj, tag, now, tx, B_TRUE));
787 }
788
789 /*
790 * Release a temporary hold for the given dataset object and tag.
791 */
792 int
dsl_pool_user_release(dsl_pool_t * dp,uint64_t dsobj,const char * tag,dmu_tx_t * tx)793 dsl_pool_user_release(dsl_pool_t *dp, uint64_t dsobj, const char *tag,
794 dmu_tx_t *tx)
795 {
796 return (dsl_pool_user_hold_rele_impl(dp, dsobj, tag, NULL,
797 tx, B_FALSE));
798 }
799