Print this page
3954 metaslabs continue to load even after hitting zfs_mg_alloc_failure limit
4080 zpool clear fails to clear pool
4081 need zfs_mg_noalloc_threshold
Reviewed by: Adam Leventhal <ahl@delphix.com>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
| Split |
Close |
| Expand all |
| Collapse all |
--- old/usr/src/uts/common/fs/zfs/zio.c
+++ new/usr/src/uts/common/fs/zfs/zio.c
1 1 /*
2 2 * CDDL HEADER START
3 3 *
4 4 * The contents of this file are subject to the terms of the
5 5 * Common Development and Distribution License (the "License").
6 6 * You may not use this file except in compliance with the License.
7 7 *
8 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 9 * or http://www.opensolaris.org/os/licensing.
10 10 * See the License for the specific language governing permissions
11 11 * and limitations under the License.
12 12 *
13 13 * When distributing Covered Code, include this CDDL HEADER in each
14 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 15 * If applicable, add the following below this CDDL HEADER, with the
16 16 * fields enclosed by brackets "[]" replaced with your own identifying
17 17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 18 *
19 19 * CDDL HEADER END
20 20 */
21 21 /*
22 22 * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
23 23 * Copyright (c) 2013 by Delphix. All rights reserved.
24 24 * Copyright (c) 2011 Nexenta Systems, Inc. All rights reserved.
25 25 */
26 26
27 27 #include <sys/zfs_context.h>
28 28 #include <sys/fm/fs/zfs.h>
29 29 #include <sys/spa.h>
30 30 #include <sys/txg.h>
31 31 #include <sys/spa_impl.h>
32 32 #include <sys/vdev_impl.h>
33 33 #include <sys/zio_impl.h>
34 34 #include <sys/zio_compress.h>
35 35 #include <sys/zio_checksum.h>
36 36 #include <sys/dmu_objset.h>
37 37 #include <sys/arc.h>
38 38 #include <sys/ddt.h>
39 39
40 40 /*
41 41 * ==========================================================================
42 42 * I/O type descriptions
43 43 * ==========================================================================
44 44 */
45 45 const char *zio_type_name[ZIO_TYPES] = {
46 46 "zio_null", "zio_read", "zio_write", "zio_free", "zio_claim",
47 47 "zio_ioctl"
48 48 };
49 49
50 50 /*
51 51 * ==========================================================================
52 52 * I/O kmem caches
53 53 * ==========================================================================
54 54 */
55 55 kmem_cache_t *zio_cache;
56 56 kmem_cache_t *zio_link_cache;
57 57 kmem_cache_t *zio_buf_cache[SPA_MAXBLOCKSIZE >> SPA_MINBLOCKSHIFT];
58 58 kmem_cache_t *zio_data_buf_cache[SPA_MAXBLOCKSIZE >> SPA_MINBLOCKSHIFT];
59 59
60 60 #ifdef _KERNEL
61 61 extern vmem_t *zio_alloc_arena;
62 62 #endif
63 63 extern int zfs_mg_alloc_failures;
64 64
65 65 /*
66 66 * The following actions directly effect the spa's sync-to-convergence logic.
67 67 * The values below define the sync pass when we start performing the action.
68 68 * Care should be taken when changing these values as they directly impact
69 69 * spa_sync() performance. Tuning these values may introduce subtle performance
70 70 * pathologies and should only be done in the context of performance analysis.
71 71 * These tunables will eventually be removed and replaced with #defines once
72 72 * enough analysis has been done to determine optimal values.
73 73 *
74 74 * The 'zfs_sync_pass_deferred_free' pass must be greater than 1 to ensure that
75 75 * regular blocks are not deferred.
76 76 */
77 77 int zfs_sync_pass_deferred_free = 2; /* defer frees starting in this pass */
78 78 int zfs_sync_pass_dont_compress = 5; /* don't compress starting in this pass */
79 79 int zfs_sync_pass_rewrite = 2; /* rewrite new bps starting in this pass */
80 80
81 81 /*
82 82 * An allocating zio is one that either currently has the DVA allocate
83 83 * stage set or will have it later in its lifetime.
84 84 */
85 85 #define IO_IS_ALLOCATING(zio) ((zio)->io_orig_pipeline & ZIO_STAGE_DVA_ALLOCATE)
86 86
87 87 boolean_t zio_requeue_io_start_cut_in_line = B_TRUE;
88 88
89 89 #ifdef ZFS_DEBUG
90 90 int zio_buf_debug_limit = 16384;
91 91 #else
92 92 int zio_buf_debug_limit = 0;
93 93 #endif
94 94
95 95 void
96 96 zio_init(void)
97 97 {
98 98 size_t c;
99 99 vmem_t *data_alloc_arena = NULL;
100 100
101 101 #ifdef _KERNEL
102 102 data_alloc_arena = zio_alloc_arena;
103 103 #endif
104 104 zio_cache = kmem_cache_create("zio_cache",
105 105 sizeof (zio_t), 0, NULL, NULL, NULL, NULL, NULL, 0);
106 106 zio_link_cache = kmem_cache_create("zio_link_cache",
107 107 sizeof (zio_link_t), 0, NULL, NULL, NULL, NULL, NULL, 0);
108 108
109 109 /*
110 110 * For small buffers, we want a cache for each multiple of
111 111 * SPA_MINBLOCKSIZE. For medium-size buffers, we want a cache
112 112 * for each quarter-power of 2. For large buffers, we want
113 113 * a cache for each multiple of PAGESIZE.
114 114 */
115 115 for (c = 0; c < SPA_MAXBLOCKSIZE >> SPA_MINBLOCKSHIFT; c++) {
116 116 size_t size = (c + 1) << SPA_MINBLOCKSHIFT;
117 117 size_t p2 = size;
118 118 size_t align = 0;
119 119 size_t cflags = (size > zio_buf_debug_limit) ? KMC_NODEBUG : 0;
120 120
121 121 while (p2 & (p2 - 1))
122 122 p2 &= p2 - 1;
123 123
124 124 #ifndef _KERNEL
125 125 /*
126 126 * If we are using watchpoints, put each buffer on its own page,
127 127 * to eliminate the performance overhead of trapping to the
128 128 * kernel when modifying a non-watched buffer that shares the
129 129 * page with a watched buffer.
130 130 */
131 131 if (arc_watch && !IS_P2ALIGNED(size, PAGESIZE))
132 132 continue;
133 133 #endif
134 134 if (size <= 4 * SPA_MINBLOCKSIZE) {
135 135 align = SPA_MINBLOCKSIZE;
136 136 } else if (IS_P2ALIGNED(size, PAGESIZE)) {
137 137 align = PAGESIZE;
138 138 } else if (IS_P2ALIGNED(size, p2 >> 2)) {
139 139 align = p2 >> 2;
140 140 }
141 141
142 142 if (align != 0) {
143 143 char name[36];
144 144 (void) sprintf(name, "zio_buf_%lu", (ulong_t)size);
145 145 zio_buf_cache[c] = kmem_cache_create(name, size,
146 146 align, NULL, NULL, NULL, NULL, NULL, cflags);
147 147
148 148 /*
149 149 * Since zio_data bufs do not appear in crash dumps, we
150 150 * pass KMC_NOTOUCH so that no allocator metadata is
151 151 * stored with the buffers.
152 152 */
153 153 (void) sprintf(name, "zio_data_buf_%lu", (ulong_t)size);
154 154 zio_data_buf_cache[c] = kmem_cache_create(name, size,
155 155 align, NULL, NULL, NULL, NULL, data_alloc_arena,
156 156 cflags | KMC_NOTOUCH);
157 157 }
158 158 }
159 159
160 160 while (--c != 0) {
161 161 ASSERT(zio_buf_cache[c] != NULL);
162 162 if (zio_buf_cache[c - 1] == NULL)
163 163 zio_buf_cache[c - 1] = zio_buf_cache[c];
|
↓ open down ↓ |
163 lines elided |
↑ open up ↑ |
164 164
165 165 ASSERT(zio_data_buf_cache[c] != NULL);
166 166 if (zio_data_buf_cache[c - 1] == NULL)
167 167 zio_data_buf_cache[c - 1] = zio_data_buf_cache[c];
168 168 }
169 169
170 170 /*
171 171 * The zio write taskqs have 1 thread per cpu, allow 1/2 of the taskqs
172 172 * to fail 3 times per txg or 8 failures, whichever is greater.
173 173 */
174 - zfs_mg_alloc_failures = MAX((3 * max_ncpus / 2), 8);
174 + if (zfs_mg_alloc_failures == 0)
175 + zfs_mg_alloc_failures = MAX((3 * max_ncpus / 2), 8);
175 176
176 177 zio_inject_init();
177 178 }
178 179
179 180 void
180 181 zio_fini(void)
181 182 {
182 183 size_t c;
183 184 kmem_cache_t *last_cache = NULL;
184 185 kmem_cache_t *last_data_cache = NULL;
185 186
186 187 for (c = 0; c < SPA_MAXBLOCKSIZE >> SPA_MINBLOCKSHIFT; c++) {
187 188 if (zio_buf_cache[c] != last_cache) {
188 189 last_cache = zio_buf_cache[c];
189 190 kmem_cache_destroy(zio_buf_cache[c]);
190 191 }
191 192 zio_buf_cache[c] = NULL;
192 193
193 194 if (zio_data_buf_cache[c] != last_data_cache) {
194 195 last_data_cache = zio_data_buf_cache[c];
195 196 kmem_cache_destroy(zio_data_buf_cache[c]);
196 197 }
197 198 zio_data_buf_cache[c] = NULL;
198 199 }
199 200
200 201 kmem_cache_destroy(zio_link_cache);
201 202 kmem_cache_destroy(zio_cache);
202 203
203 204 zio_inject_fini();
204 205 }
205 206
206 207 /*
207 208 * ==========================================================================
208 209 * Allocate and free I/O buffers
209 210 * ==========================================================================
210 211 */
211 212
212 213 /*
213 214 * Use zio_buf_alloc to allocate ZFS metadata. This data will appear in a
214 215 * crashdump if the kernel panics, so use it judiciously. Obviously, it's
215 216 * useful to inspect ZFS metadata, but if possible, we should avoid keeping
216 217 * excess / transient data in-core during a crashdump.
217 218 */
218 219 void *
219 220 zio_buf_alloc(size_t size)
220 221 {
221 222 size_t c = (size - 1) >> SPA_MINBLOCKSHIFT;
222 223
223 224 ASSERT(c < SPA_MAXBLOCKSIZE >> SPA_MINBLOCKSHIFT);
224 225
225 226 return (kmem_cache_alloc(zio_buf_cache[c], KM_PUSHPAGE));
226 227 }
227 228
228 229 /*
229 230 * Use zio_data_buf_alloc to allocate data. The data will not appear in a
230 231 * crashdump if the kernel panics. This exists so that we will limit the amount
231 232 * of ZFS data that shows up in a kernel crashdump. (Thus reducing the amount
232 233 * of kernel heap dumped to disk when the kernel panics)
233 234 */
234 235 void *
235 236 zio_data_buf_alloc(size_t size)
236 237 {
237 238 size_t c = (size - 1) >> SPA_MINBLOCKSHIFT;
238 239
239 240 ASSERT(c < SPA_MAXBLOCKSIZE >> SPA_MINBLOCKSHIFT);
240 241
241 242 return (kmem_cache_alloc(zio_data_buf_cache[c], KM_PUSHPAGE));
242 243 }
243 244
244 245 void
245 246 zio_buf_free(void *buf, size_t size)
246 247 {
247 248 size_t c = (size - 1) >> SPA_MINBLOCKSHIFT;
248 249
249 250 ASSERT(c < SPA_MAXBLOCKSIZE >> SPA_MINBLOCKSHIFT);
250 251
251 252 kmem_cache_free(zio_buf_cache[c], buf);
252 253 }
253 254
254 255 void
255 256 zio_data_buf_free(void *buf, size_t size)
256 257 {
257 258 size_t c = (size - 1) >> SPA_MINBLOCKSHIFT;
258 259
259 260 ASSERT(c < SPA_MAXBLOCKSIZE >> SPA_MINBLOCKSHIFT);
260 261
261 262 kmem_cache_free(zio_data_buf_cache[c], buf);
262 263 }
263 264
264 265 /*
265 266 * ==========================================================================
266 267 * Push and pop I/O transform buffers
267 268 * ==========================================================================
268 269 */
269 270 static void
270 271 zio_push_transform(zio_t *zio, void *data, uint64_t size, uint64_t bufsize,
271 272 zio_transform_func_t *transform)
272 273 {
273 274 zio_transform_t *zt = kmem_alloc(sizeof (zio_transform_t), KM_SLEEP);
274 275
275 276 zt->zt_orig_data = zio->io_data;
276 277 zt->zt_orig_size = zio->io_size;
277 278 zt->zt_bufsize = bufsize;
278 279 zt->zt_transform = transform;
279 280
280 281 zt->zt_next = zio->io_transform_stack;
281 282 zio->io_transform_stack = zt;
282 283
283 284 zio->io_data = data;
284 285 zio->io_size = size;
285 286 }
286 287
287 288 static void
288 289 zio_pop_transforms(zio_t *zio)
289 290 {
290 291 zio_transform_t *zt;
291 292
292 293 while ((zt = zio->io_transform_stack) != NULL) {
293 294 if (zt->zt_transform != NULL)
294 295 zt->zt_transform(zio,
295 296 zt->zt_orig_data, zt->zt_orig_size);
296 297
297 298 if (zt->zt_bufsize != 0)
298 299 zio_buf_free(zio->io_data, zt->zt_bufsize);
299 300
300 301 zio->io_data = zt->zt_orig_data;
301 302 zio->io_size = zt->zt_orig_size;
302 303 zio->io_transform_stack = zt->zt_next;
303 304
304 305 kmem_free(zt, sizeof (zio_transform_t));
305 306 }
306 307 }
307 308
308 309 /*
309 310 * ==========================================================================
310 311 * I/O transform callbacks for subblocks and decompression
311 312 * ==========================================================================
312 313 */
313 314 static void
314 315 zio_subblock(zio_t *zio, void *data, uint64_t size)
315 316 {
316 317 ASSERT(zio->io_size > size);
317 318
318 319 if (zio->io_type == ZIO_TYPE_READ)
319 320 bcopy(zio->io_data, data, size);
320 321 }
321 322
322 323 static void
323 324 zio_decompress(zio_t *zio, void *data, uint64_t size)
324 325 {
325 326 if (zio->io_error == 0 &&
326 327 zio_decompress_data(BP_GET_COMPRESS(zio->io_bp),
327 328 zio->io_data, data, zio->io_size, size) != 0)
328 329 zio->io_error = SET_ERROR(EIO);
329 330 }
330 331
331 332 /*
332 333 * ==========================================================================
333 334 * I/O parent/child relationships and pipeline interlocks
334 335 * ==========================================================================
335 336 */
336 337 /*
337 338 * NOTE - Callers to zio_walk_parents() and zio_walk_children must
338 339 * continue calling these functions until they return NULL.
339 340 * Otherwise, the next caller will pick up the list walk in
340 341 * some indeterminate state. (Otherwise every caller would
341 342 * have to pass in a cookie to keep the state represented by
342 343 * io_walk_link, which gets annoying.)
343 344 */
344 345 zio_t *
345 346 zio_walk_parents(zio_t *cio)
346 347 {
347 348 zio_link_t *zl = cio->io_walk_link;
348 349 list_t *pl = &cio->io_parent_list;
349 350
350 351 zl = (zl == NULL) ? list_head(pl) : list_next(pl, zl);
351 352 cio->io_walk_link = zl;
352 353
353 354 if (zl == NULL)
354 355 return (NULL);
355 356
356 357 ASSERT(zl->zl_child == cio);
357 358 return (zl->zl_parent);
358 359 }
359 360
360 361 zio_t *
361 362 zio_walk_children(zio_t *pio)
362 363 {
363 364 zio_link_t *zl = pio->io_walk_link;
364 365 list_t *cl = &pio->io_child_list;
365 366
366 367 zl = (zl == NULL) ? list_head(cl) : list_next(cl, zl);
367 368 pio->io_walk_link = zl;
368 369
369 370 if (zl == NULL)
370 371 return (NULL);
371 372
372 373 ASSERT(zl->zl_parent == pio);
373 374 return (zl->zl_child);
374 375 }
375 376
376 377 zio_t *
377 378 zio_unique_parent(zio_t *cio)
378 379 {
379 380 zio_t *pio = zio_walk_parents(cio);
380 381
381 382 VERIFY(zio_walk_parents(cio) == NULL);
382 383 return (pio);
383 384 }
384 385
385 386 void
386 387 zio_add_child(zio_t *pio, zio_t *cio)
387 388 {
388 389 zio_link_t *zl = kmem_cache_alloc(zio_link_cache, KM_SLEEP);
389 390
390 391 /*
391 392 * Logical I/Os can have logical, gang, or vdev children.
392 393 * Gang I/Os can have gang or vdev children.
393 394 * Vdev I/Os can only have vdev children.
394 395 * The following ASSERT captures all of these constraints.
395 396 */
396 397 ASSERT(cio->io_child_type <= pio->io_child_type);
397 398
398 399 zl->zl_parent = pio;
399 400 zl->zl_child = cio;
400 401
401 402 mutex_enter(&cio->io_lock);
402 403 mutex_enter(&pio->io_lock);
403 404
404 405 ASSERT(pio->io_state[ZIO_WAIT_DONE] == 0);
405 406
406 407 for (int w = 0; w < ZIO_WAIT_TYPES; w++)
407 408 pio->io_children[cio->io_child_type][w] += !cio->io_state[w];
408 409
409 410 list_insert_head(&pio->io_child_list, zl);
410 411 list_insert_head(&cio->io_parent_list, zl);
411 412
412 413 pio->io_child_count++;
413 414 cio->io_parent_count++;
414 415
415 416 mutex_exit(&pio->io_lock);
416 417 mutex_exit(&cio->io_lock);
417 418 }
418 419
419 420 static void
420 421 zio_remove_child(zio_t *pio, zio_t *cio, zio_link_t *zl)
421 422 {
422 423 ASSERT(zl->zl_parent == pio);
423 424 ASSERT(zl->zl_child == cio);
424 425
425 426 mutex_enter(&cio->io_lock);
426 427 mutex_enter(&pio->io_lock);
427 428
428 429 list_remove(&pio->io_child_list, zl);
429 430 list_remove(&cio->io_parent_list, zl);
430 431
431 432 pio->io_child_count--;
432 433 cio->io_parent_count--;
433 434
434 435 mutex_exit(&pio->io_lock);
435 436 mutex_exit(&cio->io_lock);
436 437
437 438 kmem_cache_free(zio_link_cache, zl);
438 439 }
439 440
440 441 static boolean_t
441 442 zio_wait_for_children(zio_t *zio, enum zio_child child, enum zio_wait_type wait)
442 443 {
443 444 uint64_t *countp = &zio->io_children[child][wait];
444 445 boolean_t waiting = B_FALSE;
445 446
446 447 mutex_enter(&zio->io_lock);
447 448 ASSERT(zio->io_stall == NULL);
448 449 if (*countp != 0) {
449 450 zio->io_stage >>= 1;
450 451 zio->io_stall = countp;
451 452 waiting = B_TRUE;
452 453 }
453 454 mutex_exit(&zio->io_lock);
454 455
455 456 return (waiting);
456 457 }
457 458
458 459 static void
459 460 zio_notify_parent(zio_t *pio, zio_t *zio, enum zio_wait_type wait)
460 461 {
461 462 uint64_t *countp = &pio->io_children[zio->io_child_type][wait];
462 463 int *errorp = &pio->io_child_error[zio->io_child_type];
463 464
464 465 mutex_enter(&pio->io_lock);
465 466 if (zio->io_error && !(zio->io_flags & ZIO_FLAG_DONT_PROPAGATE))
466 467 *errorp = zio_worst_error(*errorp, zio->io_error);
467 468 pio->io_reexecute |= zio->io_reexecute;
468 469 ASSERT3U(*countp, >, 0);
469 470
470 471 (*countp)--;
471 472
472 473 if (*countp == 0 && pio->io_stall == countp) {
473 474 pio->io_stall = NULL;
474 475 mutex_exit(&pio->io_lock);
475 476 zio_execute(pio);
476 477 } else {
477 478 mutex_exit(&pio->io_lock);
478 479 }
479 480 }
480 481
481 482 static void
482 483 zio_inherit_child_errors(zio_t *zio, enum zio_child c)
483 484 {
484 485 if (zio->io_child_error[c] != 0 && zio->io_error == 0)
485 486 zio->io_error = zio->io_child_error[c];
486 487 }
487 488
488 489 /*
489 490 * ==========================================================================
490 491 * Create the various types of I/O (read, write, free, etc)
491 492 * ==========================================================================
492 493 */
493 494 static zio_t *
494 495 zio_create(zio_t *pio, spa_t *spa, uint64_t txg, const blkptr_t *bp,
495 496 void *data, uint64_t size, zio_done_func_t *done, void *private,
496 497 zio_type_t type, zio_priority_t priority, enum zio_flag flags,
497 498 vdev_t *vd, uint64_t offset, const zbookmark_t *zb,
498 499 enum zio_stage stage, enum zio_stage pipeline)
499 500 {
500 501 zio_t *zio;
501 502
502 503 ASSERT3U(size, <=, SPA_MAXBLOCKSIZE);
503 504 ASSERT(P2PHASE(size, SPA_MINBLOCKSIZE) == 0);
504 505 ASSERT(P2PHASE(offset, SPA_MINBLOCKSIZE) == 0);
505 506
506 507 ASSERT(!vd || spa_config_held(spa, SCL_STATE_ALL, RW_READER));
507 508 ASSERT(!bp || !(flags & ZIO_FLAG_CONFIG_WRITER));
508 509 ASSERT(vd || stage == ZIO_STAGE_OPEN);
509 510
510 511 zio = kmem_cache_alloc(zio_cache, KM_SLEEP);
511 512 bzero(zio, sizeof (zio_t));
512 513
513 514 mutex_init(&zio->io_lock, NULL, MUTEX_DEFAULT, NULL);
514 515 cv_init(&zio->io_cv, NULL, CV_DEFAULT, NULL);
515 516
516 517 list_create(&zio->io_parent_list, sizeof (zio_link_t),
517 518 offsetof(zio_link_t, zl_parent_node));
518 519 list_create(&zio->io_child_list, sizeof (zio_link_t),
519 520 offsetof(zio_link_t, zl_child_node));
520 521
521 522 if (vd != NULL)
522 523 zio->io_child_type = ZIO_CHILD_VDEV;
523 524 else if (flags & ZIO_FLAG_GANG_CHILD)
524 525 zio->io_child_type = ZIO_CHILD_GANG;
525 526 else if (flags & ZIO_FLAG_DDT_CHILD)
526 527 zio->io_child_type = ZIO_CHILD_DDT;
527 528 else
528 529 zio->io_child_type = ZIO_CHILD_LOGICAL;
529 530
530 531 if (bp != NULL) {
531 532 zio->io_bp = (blkptr_t *)bp;
532 533 zio->io_bp_copy = *bp;
533 534 zio->io_bp_orig = *bp;
534 535 if (type != ZIO_TYPE_WRITE ||
535 536 zio->io_child_type == ZIO_CHILD_DDT)
536 537 zio->io_bp = &zio->io_bp_copy; /* so caller can free */
537 538 if (zio->io_child_type == ZIO_CHILD_LOGICAL)
538 539 zio->io_logical = zio;
539 540 if (zio->io_child_type > ZIO_CHILD_GANG && BP_IS_GANG(bp))
540 541 pipeline |= ZIO_GANG_STAGES;
541 542 }
542 543
543 544 zio->io_spa = spa;
544 545 zio->io_txg = txg;
545 546 zio->io_done = done;
546 547 zio->io_private = private;
547 548 zio->io_type = type;
548 549 zio->io_priority = priority;
549 550 zio->io_vd = vd;
550 551 zio->io_offset = offset;
551 552 zio->io_orig_data = zio->io_data = data;
552 553 zio->io_orig_size = zio->io_size = size;
553 554 zio->io_orig_flags = zio->io_flags = flags;
554 555 zio->io_orig_stage = zio->io_stage = stage;
555 556 zio->io_orig_pipeline = zio->io_pipeline = pipeline;
556 557
557 558 zio->io_state[ZIO_WAIT_READY] = (stage >= ZIO_STAGE_READY);
558 559 zio->io_state[ZIO_WAIT_DONE] = (stage >= ZIO_STAGE_DONE);
559 560
560 561 if (zb != NULL)
561 562 zio->io_bookmark = *zb;
562 563
563 564 if (pio != NULL) {
564 565 if (zio->io_logical == NULL)
565 566 zio->io_logical = pio->io_logical;
566 567 if (zio->io_child_type == ZIO_CHILD_GANG)
567 568 zio->io_gang_leader = pio->io_gang_leader;
568 569 zio_add_child(pio, zio);
569 570 }
570 571
571 572 return (zio);
572 573 }
573 574
574 575 static void
575 576 zio_destroy(zio_t *zio)
576 577 {
577 578 list_destroy(&zio->io_parent_list);
578 579 list_destroy(&zio->io_child_list);
579 580 mutex_destroy(&zio->io_lock);
580 581 cv_destroy(&zio->io_cv);
581 582 kmem_cache_free(zio_cache, zio);
582 583 }
583 584
584 585 zio_t *
585 586 zio_null(zio_t *pio, spa_t *spa, vdev_t *vd, zio_done_func_t *done,
586 587 void *private, enum zio_flag flags)
587 588 {
588 589 zio_t *zio;
589 590
590 591 zio = zio_create(pio, spa, 0, NULL, NULL, 0, done, private,
591 592 ZIO_TYPE_NULL, ZIO_PRIORITY_NOW, flags, vd, 0, NULL,
592 593 ZIO_STAGE_OPEN, ZIO_INTERLOCK_PIPELINE);
593 594
594 595 return (zio);
595 596 }
596 597
597 598 zio_t *
598 599 zio_root(spa_t *spa, zio_done_func_t *done, void *private, enum zio_flag flags)
599 600 {
600 601 return (zio_null(NULL, spa, NULL, done, private, flags));
601 602 }
602 603
603 604 zio_t *
604 605 zio_read(zio_t *pio, spa_t *spa, const blkptr_t *bp,
605 606 void *data, uint64_t size, zio_done_func_t *done, void *private,
606 607 zio_priority_t priority, enum zio_flag flags, const zbookmark_t *zb)
607 608 {
608 609 zio_t *zio;
609 610
610 611 zio = zio_create(pio, spa, BP_PHYSICAL_BIRTH(bp), bp,
611 612 data, size, done, private,
612 613 ZIO_TYPE_READ, priority, flags, NULL, 0, zb,
613 614 ZIO_STAGE_OPEN, (flags & ZIO_FLAG_DDT_CHILD) ?
614 615 ZIO_DDT_CHILD_READ_PIPELINE : ZIO_READ_PIPELINE);
615 616
616 617 return (zio);
617 618 }
618 619
619 620 zio_t *
620 621 zio_write(zio_t *pio, spa_t *spa, uint64_t txg, blkptr_t *bp,
621 622 void *data, uint64_t size, const zio_prop_t *zp,
622 623 zio_done_func_t *ready, zio_done_func_t *physdone, zio_done_func_t *done,
623 624 void *private,
624 625 zio_priority_t priority, enum zio_flag flags, const zbookmark_t *zb)
625 626 {
626 627 zio_t *zio;
627 628
628 629 ASSERT(zp->zp_checksum >= ZIO_CHECKSUM_OFF &&
629 630 zp->zp_checksum < ZIO_CHECKSUM_FUNCTIONS &&
630 631 zp->zp_compress >= ZIO_COMPRESS_OFF &&
631 632 zp->zp_compress < ZIO_COMPRESS_FUNCTIONS &&
632 633 DMU_OT_IS_VALID(zp->zp_type) &&
633 634 zp->zp_level < 32 &&
634 635 zp->zp_copies > 0 &&
635 636 zp->zp_copies <= spa_max_replication(spa));
636 637
637 638 zio = zio_create(pio, spa, txg, bp, data, size, done, private,
638 639 ZIO_TYPE_WRITE, priority, flags, NULL, 0, zb,
639 640 ZIO_STAGE_OPEN, (flags & ZIO_FLAG_DDT_CHILD) ?
640 641 ZIO_DDT_CHILD_WRITE_PIPELINE : ZIO_WRITE_PIPELINE);
641 642
642 643 zio->io_ready = ready;
643 644 zio->io_physdone = physdone;
644 645 zio->io_prop = *zp;
645 646
646 647 return (zio);
647 648 }
648 649
649 650 zio_t *
650 651 zio_rewrite(zio_t *pio, spa_t *spa, uint64_t txg, blkptr_t *bp, void *data,
651 652 uint64_t size, zio_done_func_t *done, void *private,
652 653 zio_priority_t priority, enum zio_flag flags, zbookmark_t *zb)
653 654 {
654 655 zio_t *zio;
655 656
656 657 zio = zio_create(pio, spa, txg, bp, data, size, done, private,
657 658 ZIO_TYPE_WRITE, priority, flags, NULL, 0, zb,
658 659 ZIO_STAGE_OPEN, ZIO_REWRITE_PIPELINE);
659 660
660 661 return (zio);
661 662 }
662 663
663 664 void
664 665 zio_write_override(zio_t *zio, blkptr_t *bp, int copies, boolean_t nopwrite)
665 666 {
666 667 ASSERT(zio->io_type == ZIO_TYPE_WRITE);
667 668 ASSERT(zio->io_child_type == ZIO_CHILD_LOGICAL);
668 669 ASSERT(zio->io_stage == ZIO_STAGE_OPEN);
669 670 ASSERT(zio->io_txg == spa_syncing_txg(zio->io_spa));
670 671
671 672 /*
672 673 * We must reset the io_prop to match the values that existed
673 674 * when the bp was first written by dmu_sync() keeping in mind
674 675 * that nopwrite and dedup are mutually exclusive.
675 676 */
676 677 zio->io_prop.zp_dedup = nopwrite ? B_FALSE : zio->io_prop.zp_dedup;
677 678 zio->io_prop.zp_nopwrite = nopwrite;
678 679 zio->io_prop.zp_copies = copies;
679 680 zio->io_bp_override = bp;
680 681 }
681 682
682 683 void
683 684 zio_free(spa_t *spa, uint64_t txg, const blkptr_t *bp)
684 685 {
685 686 metaslab_check_free(spa, bp);
686 687
687 688 /*
688 689 * Frees that are for the currently-syncing txg, are not going to be
689 690 * deferred, and which will not need to do a read (i.e. not GANG or
690 691 * DEDUP), can be processed immediately. Otherwise, put them on the
691 692 * in-memory list for later processing.
692 693 */
693 694 if (BP_IS_GANG(bp) || BP_GET_DEDUP(bp) ||
694 695 txg != spa->spa_syncing_txg ||
695 696 spa_sync_pass(spa) >= zfs_sync_pass_deferred_free) {
696 697 bplist_append(&spa->spa_free_bplist[txg & TXG_MASK], bp);
697 698 } else {
698 699 VERIFY0(zio_wait(zio_free_sync(NULL, spa, txg, bp, 0)));
699 700 }
700 701 }
701 702
702 703 zio_t *
703 704 zio_free_sync(zio_t *pio, spa_t *spa, uint64_t txg, const blkptr_t *bp,
704 705 enum zio_flag flags)
705 706 {
706 707 zio_t *zio;
707 708 enum zio_stage stage = ZIO_FREE_PIPELINE;
708 709
709 710 dprintf_bp(bp, "freeing in txg %llu, pass %u",
710 711 (longlong_t)txg, spa->spa_sync_pass);
711 712
712 713 ASSERT(!BP_IS_HOLE(bp));
713 714 ASSERT(spa_syncing_txg(spa) == txg);
714 715 ASSERT(spa_sync_pass(spa) < zfs_sync_pass_deferred_free);
715 716
716 717 metaslab_check_free(spa, bp);
717 718 arc_freed(spa, bp);
718 719
719 720 /*
720 721 * GANG and DEDUP blocks can induce a read (for the gang block header,
721 722 * or the DDT), so issue them asynchronously so that this thread is
722 723 * not tied up.
723 724 */
724 725 if (BP_IS_GANG(bp) || BP_GET_DEDUP(bp))
725 726 stage |= ZIO_STAGE_ISSUE_ASYNC;
726 727
727 728 zio = zio_create(pio, spa, txg, bp, NULL, BP_GET_PSIZE(bp),
728 729 NULL, NULL, ZIO_TYPE_FREE, ZIO_PRIORITY_NOW, flags,
729 730 NULL, 0, NULL, ZIO_STAGE_OPEN, stage);
730 731
731 732
732 733 return (zio);
733 734 }
734 735
735 736 zio_t *
736 737 zio_claim(zio_t *pio, spa_t *spa, uint64_t txg, const blkptr_t *bp,
737 738 zio_done_func_t *done, void *private, enum zio_flag flags)
738 739 {
739 740 zio_t *zio;
740 741
741 742 /*
742 743 * A claim is an allocation of a specific block. Claims are needed
743 744 * to support immediate writes in the intent log. The issue is that
744 745 * immediate writes contain committed data, but in a txg that was
745 746 * *not* committed. Upon opening the pool after an unclean shutdown,
746 747 * the intent log claims all blocks that contain immediate write data
747 748 * so that the SPA knows they're in use.
748 749 *
749 750 * All claims *must* be resolved in the first txg -- before the SPA
750 751 * starts allocating blocks -- so that nothing is allocated twice.
751 752 * If txg == 0 we just verify that the block is claimable.
752 753 */
753 754 ASSERT3U(spa->spa_uberblock.ub_rootbp.blk_birth, <, spa_first_txg(spa));
754 755 ASSERT(txg == spa_first_txg(spa) || txg == 0);
755 756 ASSERT(!BP_GET_DEDUP(bp) || !spa_writeable(spa)); /* zdb(1M) */
756 757
757 758 zio = zio_create(pio, spa, txg, bp, NULL, BP_GET_PSIZE(bp),
758 759 done, private, ZIO_TYPE_CLAIM, ZIO_PRIORITY_NOW, flags,
759 760 NULL, 0, NULL, ZIO_STAGE_OPEN, ZIO_CLAIM_PIPELINE);
760 761
761 762 return (zio);
762 763 }
763 764
764 765 zio_t *
765 766 zio_ioctl(zio_t *pio, spa_t *spa, vdev_t *vd, int cmd,
766 767 zio_done_func_t *done, void *private, enum zio_flag flags)
767 768 {
768 769 zio_t *zio;
769 770 int c;
770 771
771 772 if (vd->vdev_children == 0) {
772 773 zio = zio_create(pio, spa, 0, NULL, NULL, 0, done, private,
773 774 ZIO_TYPE_IOCTL, ZIO_PRIORITY_NOW, flags, vd, 0, NULL,
774 775 ZIO_STAGE_OPEN, ZIO_IOCTL_PIPELINE);
775 776
776 777 zio->io_cmd = cmd;
777 778 } else {
778 779 zio = zio_null(pio, spa, NULL, NULL, NULL, flags);
779 780
780 781 for (c = 0; c < vd->vdev_children; c++)
781 782 zio_nowait(zio_ioctl(zio, spa, vd->vdev_child[c], cmd,
782 783 done, private, flags));
783 784 }
784 785
785 786 return (zio);
786 787 }
787 788
788 789 zio_t *
789 790 zio_read_phys(zio_t *pio, vdev_t *vd, uint64_t offset, uint64_t size,
790 791 void *data, int checksum, zio_done_func_t *done, void *private,
791 792 zio_priority_t priority, enum zio_flag flags, boolean_t labels)
792 793 {
793 794 zio_t *zio;
794 795
795 796 ASSERT(vd->vdev_children == 0);
796 797 ASSERT(!labels || offset + size <= VDEV_LABEL_START_SIZE ||
797 798 offset >= vd->vdev_psize - VDEV_LABEL_END_SIZE);
798 799 ASSERT3U(offset + size, <=, vd->vdev_psize);
799 800
800 801 zio = zio_create(pio, vd->vdev_spa, 0, NULL, data, size, done, private,
801 802 ZIO_TYPE_READ, priority, flags, vd, offset, NULL,
802 803 ZIO_STAGE_OPEN, ZIO_READ_PHYS_PIPELINE);
803 804
804 805 zio->io_prop.zp_checksum = checksum;
805 806
806 807 return (zio);
807 808 }
808 809
809 810 zio_t *
810 811 zio_write_phys(zio_t *pio, vdev_t *vd, uint64_t offset, uint64_t size,
811 812 void *data, int checksum, zio_done_func_t *done, void *private,
812 813 zio_priority_t priority, enum zio_flag flags, boolean_t labels)
813 814 {
814 815 zio_t *zio;
815 816
816 817 ASSERT(vd->vdev_children == 0);
817 818 ASSERT(!labels || offset + size <= VDEV_LABEL_START_SIZE ||
818 819 offset >= vd->vdev_psize - VDEV_LABEL_END_SIZE);
819 820 ASSERT3U(offset + size, <=, vd->vdev_psize);
820 821
821 822 zio = zio_create(pio, vd->vdev_spa, 0, NULL, data, size, done, private,
822 823 ZIO_TYPE_WRITE, priority, flags, vd, offset, NULL,
823 824 ZIO_STAGE_OPEN, ZIO_WRITE_PHYS_PIPELINE);
824 825
825 826 zio->io_prop.zp_checksum = checksum;
826 827
827 828 if (zio_checksum_table[checksum].ci_eck) {
828 829 /*
829 830 * zec checksums are necessarily destructive -- they modify
830 831 * the end of the write buffer to hold the verifier/checksum.
831 832 * Therefore, we must make a local copy in case the data is
832 833 * being written to multiple places in parallel.
833 834 */
834 835 void *wbuf = zio_buf_alloc(size);
835 836 bcopy(data, wbuf, size);
836 837 zio_push_transform(zio, wbuf, size, size, NULL);
837 838 }
838 839
839 840 return (zio);
840 841 }
841 842
842 843 /*
843 844 * Create a child I/O to do some work for us.
844 845 */
845 846 zio_t *
846 847 zio_vdev_child_io(zio_t *pio, blkptr_t *bp, vdev_t *vd, uint64_t offset,
847 848 void *data, uint64_t size, int type, zio_priority_t priority,
848 849 enum zio_flag flags, zio_done_func_t *done, void *private)
849 850 {
850 851 enum zio_stage pipeline = ZIO_VDEV_CHILD_PIPELINE;
851 852 zio_t *zio;
852 853
853 854 ASSERT(vd->vdev_parent ==
854 855 (pio->io_vd ? pio->io_vd : pio->io_spa->spa_root_vdev));
855 856
856 857 if (type == ZIO_TYPE_READ && bp != NULL) {
857 858 /*
858 859 * If we have the bp, then the child should perform the
859 860 * checksum and the parent need not. This pushes error
860 861 * detection as close to the leaves as possible and
861 862 * eliminates redundant checksums in the interior nodes.
862 863 */
863 864 pipeline |= ZIO_STAGE_CHECKSUM_VERIFY;
864 865 pio->io_pipeline &= ~ZIO_STAGE_CHECKSUM_VERIFY;
865 866 }
866 867
867 868 if (vd->vdev_children == 0)
868 869 offset += VDEV_LABEL_START_SIZE;
869 870
870 871 flags |= ZIO_VDEV_CHILD_FLAGS(pio) | ZIO_FLAG_DONT_PROPAGATE;
871 872
872 873 /*
873 874 * If we've decided to do a repair, the write is not speculative --
874 875 * even if the original read was.
875 876 */
876 877 if (flags & ZIO_FLAG_IO_REPAIR)
877 878 flags &= ~ZIO_FLAG_SPECULATIVE;
878 879
879 880 zio = zio_create(pio, pio->io_spa, pio->io_txg, bp, data, size,
880 881 done, private, type, priority, flags, vd, offset, &pio->io_bookmark,
881 882 ZIO_STAGE_VDEV_IO_START >> 1, pipeline);
882 883
883 884 zio->io_physdone = pio->io_physdone;
884 885 if (vd->vdev_ops->vdev_op_leaf && zio->io_logical != NULL)
885 886 zio->io_logical->io_phys_children++;
886 887
887 888 return (zio);
888 889 }
889 890
890 891 zio_t *
891 892 zio_vdev_delegated_io(vdev_t *vd, uint64_t offset, void *data, uint64_t size,
892 893 int type, zio_priority_t priority, enum zio_flag flags,
893 894 zio_done_func_t *done, void *private)
894 895 {
895 896 zio_t *zio;
896 897
897 898 ASSERT(vd->vdev_ops->vdev_op_leaf);
898 899
899 900 zio = zio_create(NULL, vd->vdev_spa, 0, NULL,
900 901 data, size, done, private, type, priority,
901 902 flags | ZIO_FLAG_CANFAIL | ZIO_FLAG_DONT_RETRY | ZIO_FLAG_DELEGATED,
902 903 vd, offset, NULL,
903 904 ZIO_STAGE_VDEV_IO_START >> 1, ZIO_VDEV_CHILD_PIPELINE);
904 905
905 906 return (zio);
906 907 }
907 908
908 909 void
909 910 zio_flush(zio_t *zio, vdev_t *vd)
910 911 {
911 912 zio_nowait(zio_ioctl(zio, zio->io_spa, vd, DKIOCFLUSHWRITECACHE,
912 913 NULL, NULL,
913 914 ZIO_FLAG_CANFAIL | ZIO_FLAG_DONT_PROPAGATE | ZIO_FLAG_DONT_RETRY));
914 915 }
915 916
916 917 void
917 918 zio_shrink(zio_t *zio, uint64_t size)
918 919 {
919 920 ASSERT(zio->io_executor == NULL);
920 921 ASSERT(zio->io_orig_size == zio->io_size);
921 922 ASSERT(size <= zio->io_size);
922 923
923 924 /*
924 925 * We don't shrink for raidz because of problems with the
925 926 * reconstruction when reading back less than the block size.
926 927 * Note, BP_IS_RAIDZ() assumes no compression.
927 928 */
928 929 ASSERT(BP_GET_COMPRESS(zio->io_bp) == ZIO_COMPRESS_OFF);
929 930 if (!BP_IS_RAIDZ(zio->io_bp))
930 931 zio->io_orig_size = zio->io_size = size;
931 932 }
932 933
933 934 /*
934 935 * ==========================================================================
935 936 * Prepare to read and write logical blocks
936 937 * ==========================================================================
937 938 */
938 939
939 940 static int
940 941 zio_read_bp_init(zio_t *zio)
941 942 {
942 943 blkptr_t *bp = zio->io_bp;
943 944
944 945 if (BP_GET_COMPRESS(bp) != ZIO_COMPRESS_OFF &&
945 946 zio->io_child_type == ZIO_CHILD_LOGICAL &&
946 947 !(zio->io_flags & ZIO_FLAG_RAW)) {
947 948 uint64_t psize = BP_GET_PSIZE(bp);
948 949 void *cbuf = zio_buf_alloc(psize);
949 950
950 951 zio_push_transform(zio, cbuf, psize, psize, zio_decompress);
951 952 }
952 953
953 954 if (!DMU_OT_IS_METADATA(BP_GET_TYPE(bp)) && BP_GET_LEVEL(bp) == 0)
954 955 zio->io_flags |= ZIO_FLAG_DONT_CACHE;
955 956
956 957 if (BP_GET_TYPE(bp) == DMU_OT_DDT_ZAP)
957 958 zio->io_flags |= ZIO_FLAG_DONT_CACHE;
958 959
959 960 if (BP_GET_DEDUP(bp) && zio->io_child_type == ZIO_CHILD_LOGICAL)
960 961 zio->io_pipeline = ZIO_DDT_READ_PIPELINE;
961 962
962 963 return (ZIO_PIPELINE_CONTINUE);
963 964 }
964 965
965 966 static int
966 967 zio_write_bp_init(zio_t *zio)
967 968 {
968 969 spa_t *spa = zio->io_spa;
969 970 zio_prop_t *zp = &zio->io_prop;
970 971 enum zio_compress compress = zp->zp_compress;
971 972 blkptr_t *bp = zio->io_bp;
972 973 uint64_t lsize = zio->io_size;
973 974 uint64_t psize = lsize;
974 975 int pass = 1;
975 976
976 977 /*
977 978 * If our children haven't all reached the ready stage,
978 979 * wait for them and then repeat this pipeline stage.
979 980 */
980 981 if (zio_wait_for_children(zio, ZIO_CHILD_GANG, ZIO_WAIT_READY) ||
981 982 zio_wait_for_children(zio, ZIO_CHILD_LOGICAL, ZIO_WAIT_READY))
982 983 return (ZIO_PIPELINE_STOP);
983 984
984 985 if (!IO_IS_ALLOCATING(zio))
985 986 return (ZIO_PIPELINE_CONTINUE);
986 987
987 988 ASSERT(zio->io_child_type != ZIO_CHILD_DDT);
988 989
989 990 if (zio->io_bp_override) {
990 991 ASSERT(bp->blk_birth != zio->io_txg);
991 992 ASSERT(BP_GET_DEDUP(zio->io_bp_override) == 0);
992 993
993 994 *bp = *zio->io_bp_override;
994 995 zio->io_pipeline = ZIO_INTERLOCK_PIPELINE;
995 996
996 997 /*
997 998 * If we've been overridden and nopwrite is set then
998 999 * set the flag accordingly to indicate that a nopwrite
999 1000 * has already occurred.
1000 1001 */
1001 1002 if (!BP_IS_HOLE(bp) && zp->zp_nopwrite) {
1002 1003 ASSERT(!zp->zp_dedup);
1003 1004 zio->io_flags |= ZIO_FLAG_NOPWRITE;
1004 1005 return (ZIO_PIPELINE_CONTINUE);
1005 1006 }
1006 1007
1007 1008 ASSERT(!zp->zp_nopwrite);
1008 1009
1009 1010 if (BP_IS_HOLE(bp) || !zp->zp_dedup)
1010 1011 return (ZIO_PIPELINE_CONTINUE);
1011 1012
1012 1013 ASSERT(zio_checksum_table[zp->zp_checksum].ci_dedup ||
1013 1014 zp->zp_dedup_verify);
1014 1015
1015 1016 if (BP_GET_CHECKSUM(bp) == zp->zp_checksum) {
1016 1017 BP_SET_DEDUP(bp, 1);
1017 1018 zio->io_pipeline |= ZIO_STAGE_DDT_WRITE;
1018 1019 return (ZIO_PIPELINE_CONTINUE);
1019 1020 }
1020 1021 zio->io_bp_override = NULL;
1021 1022 BP_ZERO(bp);
1022 1023 }
1023 1024
1024 1025 if (bp->blk_birth == zio->io_txg) {
1025 1026 /*
1026 1027 * We're rewriting an existing block, which means we're
1027 1028 * working on behalf of spa_sync(). For spa_sync() to
1028 1029 * converge, it must eventually be the case that we don't
1029 1030 * have to allocate new blocks. But compression changes
1030 1031 * the blocksize, which forces a reallocate, and makes
1031 1032 * convergence take longer. Therefore, after the first
1032 1033 * few passes, stop compressing to ensure convergence.
1033 1034 */
1034 1035 pass = spa_sync_pass(spa);
1035 1036
1036 1037 ASSERT(zio->io_txg == spa_syncing_txg(spa));
1037 1038 ASSERT(zio->io_child_type == ZIO_CHILD_LOGICAL);
1038 1039 ASSERT(!BP_GET_DEDUP(bp));
1039 1040
1040 1041 if (pass >= zfs_sync_pass_dont_compress)
1041 1042 compress = ZIO_COMPRESS_OFF;
1042 1043
1043 1044 /* Make sure someone doesn't change their mind on overwrites */
1044 1045 ASSERT(MIN(zp->zp_copies + BP_IS_GANG(bp),
1045 1046 spa_max_replication(spa)) == BP_GET_NDVAS(bp));
1046 1047 }
1047 1048
1048 1049 if (compress != ZIO_COMPRESS_OFF) {
1049 1050 void *cbuf = zio_buf_alloc(lsize);
1050 1051 psize = zio_compress_data(compress, zio->io_data, cbuf, lsize);
1051 1052 if (psize == 0 || psize == lsize) {
1052 1053 compress = ZIO_COMPRESS_OFF;
1053 1054 zio_buf_free(cbuf, lsize);
1054 1055 } else {
1055 1056 ASSERT(psize < lsize);
1056 1057 zio_push_transform(zio, cbuf, psize, lsize, NULL);
1057 1058 }
1058 1059 }
1059 1060
1060 1061 /*
1061 1062 * The final pass of spa_sync() must be all rewrites, but the first
1062 1063 * few passes offer a trade-off: allocating blocks defers convergence,
1063 1064 * but newly allocated blocks are sequential, so they can be written
1064 1065 * to disk faster. Therefore, we allow the first few passes of
1065 1066 * spa_sync() to allocate new blocks, but force rewrites after that.
1066 1067 * There should only be a handful of blocks after pass 1 in any case.
1067 1068 */
1068 1069 if (bp->blk_birth == zio->io_txg && BP_GET_PSIZE(bp) == psize &&
1069 1070 pass >= zfs_sync_pass_rewrite) {
1070 1071 ASSERT(psize != 0);
1071 1072 enum zio_stage gang_stages = zio->io_pipeline & ZIO_GANG_STAGES;
1072 1073 zio->io_pipeline = ZIO_REWRITE_PIPELINE | gang_stages;
1073 1074 zio->io_flags |= ZIO_FLAG_IO_REWRITE;
1074 1075 } else {
1075 1076 BP_ZERO(bp);
1076 1077 zio->io_pipeline = ZIO_WRITE_PIPELINE;
1077 1078 }
1078 1079
1079 1080 if (psize == 0) {
1080 1081 zio->io_pipeline = ZIO_INTERLOCK_PIPELINE;
1081 1082 } else {
1082 1083 ASSERT(zp->zp_checksum != ZIO_CHECKSUM_GANG_HEADER);
1083 1084 BP_SET_LSIZE(bp, lsize);
1084 1085 BP_SET_PSIZE(bp, psize);
1085 1086 BP_SET_COMPRESS(bp, compress);
1086 1087 BP_SET_CHECKSUM(bp, zp->zp_checksum);
1087 1088 BP_SET_TYPE(bp, zp->zp_type);
1088 1089 BP_SET_LEVEL(bp, zp->zp_level);
1089 1090 BP_SET_DEDUP(bp, zp->zp_dedup);
1090 1091 BP_SET_BYTEORDER(bp, ZFS_HOST_BYTEORDER);
1091 1092 if (zp->zp_dedup) {
1092 1093 ASSERT(zio->io_child_type == ZIO_CHILD_LOGICAL);
1093 1094 ASSERT(!(zio->io_flags & ZIO_FLAG_IO_REWRITE));
1094 1095 zio->io_pipeline = ZIO_DDT_WRITE_PIPELINE;
1095 1096 }
1096 1097 if (zp->zp_nopwrite) {
1097 1098 ASSERT(zio->io_child_type == ZIO_CHILD_LOGICAL);
1098 1099 ASSERT(!(zio->io_flags & ZIO_FLAG_IO_REWRITE));
1099 1100 zio->io_pipeline |= ZIO_STAGE_NOP_WRITE;
1100 1101 }
1101 1102 }
1102 1103
1103 1104 return (ZIO_PIPELINE_CONTINUE);
1104 1105 }
1105 1106
1106 1107 static int
1107 1108 zio_free_bp_init(zio_t *zio)
1108 1109 {
1109 1110 blkptr_t *bp = zio->io_bp;
1110 1111
1111 1112 if (zio->io_child_type == ZIO_CHILD_LOGICAL) {
1112 1113 if (BP_GET_DEDUP(bp))
1113 1114 zio->io_pipeline = ZIO_DDT_FREE_PIPELINE;
1114 1115 }
1115 1116
1116 1117 return (ZIO_PIPELINE_CONTINUE);
1117 1118 }
1118 1119
1119 1120 /*
1120 1121 * ==========================================================================
1121 1122 * Execute the I/O pipeline
1122 1123 * ==========================================================================
1123 1124 */
1124 1125
1125 1126 static void
1126 1127 zio_taskq_dispatch(zio_t *zio, zio_taskq_type_t q, boolean_t cutinline)
1127 1128 {
1128 1129 spa_t *spa = zio->io_spa;
1129 1130 zio_type_t t = zio->io_type;
1130 1131 int flags = (cutinline ? TQ_FRONT : 0);
1131 1132
1132 1133 /*
1133 1134 * If we're a config writer or a probe, the normal issue and
1134 1135 * interrupt threads may all be blocked waiting for the config lock.
1135 1136 * In this case, select the otherwise-unused taskq for ZIO_TYPE_NULL.
1136 1137 */
1137 1138 if (zio->io_flags & (ZIO_FLAG_CONFIG_WRITER | ZIO_FLAG_PROBE))
1138 1139 t = ZIO_TYPE_NULL;
1139 1140
1140 1141 /*
1141 1142 * A similar issue exists for the L2ARC write thread until L2ARC 2.0.
1142 1143 */
1143 1144 if (t == ZIO_TYPE_WRITE && zio->io_vd && zio->io_vd->vdev_aux)
1144 1145 t = ZIO_TYPE_NULL;
1145 1146
1146 1147 /*
1147 1148 * If this is a high priority I/O, then use the high priority taskq if
1148 1149 * available.
1149 1150 */
1150 1151 if (zio->io_priority == ZIO_PRIORITY_NOW &&
1151 1152 spa->spa_zio_taskq[t][q + 1].stqs_count != 0)
1152 1153 q++;
1153 1154
1154 1155 ASSERT3U(q, <, ZIO_TASKQ_TYPES);
1155 1156
1156 1157 /*
1157 1158 * NB: We are assuming that the zio can only be dispatched
1158 1159 * to a single taskq at a time. It would be a grievous error
1159 1160 * to dispatch the zio to another taskq at the same time.
1160 1161 */
1161 1162 ASSERT(zio->io_tqent.tqent_next == NULL);
1162 1163 spa_taskq_dispatch_ent(spa, t, q, (task_func_t *)zio_execute, zio,
1163 1164 flags, &zio->io_tqent);
1164 1165 }
1165 1166
1166 1167 static boolean_t
1167 1168 zio_taskq_member(zio_t *zio, zio_taskq_type_t q)
1168 1169 {
1169 1170 kthread_t *executor = zio->io_executor;
1170 1171 spa_t *spa = zio->io_spa;
1171 1172
1172 1173 for (zio_type_t t = 0; t < ZIO_TYPES; t++) {
1173 1174 spa_taskqs_t *tqs = &spa->spa_zio_taskq[t][q];
1174 1175 uint_t i;
1175 1176 for (i = 0; i < tqs->stqs_count; i++) {
1176 1177 if (taskq_member(tqs->stqs_taskq[i], executor))
1177 1178 return (B_TRUE);
1178 1179 }
1179 1180 }
1180 1181
1181 1182 return (B_FALSE);
1182 1183 }
1183 1184
1184 1185 static int
1185 1186 zio_issue_async(zio_t *zio)
1186 1187 {
1187 1188 zio_taskq_dispatch(zio, ZIO_TASKQ_ISSUE, B_FALSE);
1188 1189
1189 1190 return (ZIO_PIPELINE_STOP);
1190 1191 }
1191 1192
1192 1193 void
1193 1194 zio_interrupt(zio_t *zio)
1194 1195 {
1195 1196 zio_taskq_dispatch(zio, ZIO_TASKQ_INTERRUPT, B_FALSE);
1196 1197 }
1197 1198
1198 1199 /*
1199 1200 * Execute the I/O pipeline until one of the following occurs:
1200 1201 *
1201 1202 * (1) the I/O completes
1202 1203 * (2) the pipeline stalls waiting for dependent child I/Os
1203 1204 * (3) the I/O issues, so we're waiting for an I/O completion interrupt
1204 1205 * (4) the I/O is delegated by vdev-level caching or aggregation
1205 1206 * (5) the I/O is deferred due to vdev-level queueing
1206 1207 * (6) the I/O is handed off to another thread.
1207 1208 *
1208 1209 * In all cases, the pipeline stops whenever there's no CPU work; it never
1209 1210 * burns a thread in cv_wait().
1210 1211 *
1211 1212 * There's no locking on io_stage because there's no legitimate way
1212 1213 * for multiple threads to be attempting to process the same I/O.
1213 1214 */
1214 1215 static zio_pipe_stage_t *zio_pipeline[];
1215 1216
1216 1217 void
1217 1218 zio_execute(zio_t *zio)
1218 1219 {
1219 1220 zio->io_executor = curthread;
1220 1221
1221 1222 while (zio->io_stage < ZIO_STAGE_DONE) {
1222 1223 enum zio_stage pipeline = zio->io_pipeline;
1223 1224 enum zio_stage stage = zio->io_stage;
1224 1225 int rv;
1225 1226
1226 1227 ASSERT(!MUTEX_HELD(&zio->io_lock));
1227 1228 ASSERT(ISP2(stage));
1228 1229 ASSERT(zio->io_stall == NULL);
1229 1230
1230 1231 do {
1231 1232 stage <<= 1;
1232 1233 } while ((stage & pipeline) == 0);
1233 1234
1234 1235 ASSERT(stage <= ZIO_STAGE_DONE);
1235 1236
1236 1237 /*
1237 1238 * If we are in interrupt context and this pipeline stage
1238 1239 * will grab a config lock that is held across I/O,
1239 1240 * or may wait for an I/O that needs an interrupt thread
1240 1241 * to complete, issue async to avoid deadlock.
1241 1242 *
1242 1243 * For VDEV_IO_START, we cut in line so that the io will
1243 1244 * be sent to disk promptly.
1244 1245 */
1245 1246 if ((stage & ZIO_BLOCKING_STAGES) && zio->io_vd == NULL &&
1246 1247 zio_taskq_member(zio, ZIO_TASKQ_INTERRUPT)) {
1247 1248 boolean_t cut = (stage == ZIO_STAGE_VDEV_IO_START) ?
1248 1249 zio_requeue_io_start_cut_in_line : B_FALSE;
1249 1250 zio_taskq_dispatch(zio, ZIO_TASKQ_ISSUE, cut);
1250 1251 return;
1251 1252 }
1252 1253
1253 1254 zio->io_stage = stage;
1254 1255 rv = zio_pipeline[highbit(stage) - 1](zio);
1255 1256
1256 1257 if (rv == ZIO_PIPELINE_STOP)
1257 1258 return;
1258 1259
1259 1260 ASSERT(rv == ZIO_PIPELINE_CONTINUE);
1260 1261 }
1261 1262 }
1262 1263
1263 1264 /*
1264 1265 * ==========================================================================
1265 1266 * Initiate I/O, either sync or async
1266 1267 * ==========================================================================
1267 1268 */
1268 1269 int
1269 1270 zio_wait(zio_t *zio)
1270 1271 {
1271 1272 int error;
1272 1273
1273 1274 ASSERT(zio->io_stage == ZIO_STAGE_OPEN);
1274 1275 ASSERT(zio->io_executor == NULL);
1275 1276
1276 1277 zio->io_waiter = curthread;
1277 1278
1278 1279 zio_execute(zio);
1279 1280
1280 1281 mutex_enter(&zio->io_lock);
1281 1282 while (zio->io_executor != NULL)
1282 1283 cv_wait(&zio->io_cv, &zio->io_lock);
1283 1284 mutex_exit(&zio->io_lock);
1284 1285
1285 1286 error = zio->io_error;
1286 1287 zio_destroy(zio);
1287 1288
1288 1289 return (error);
1289 1290 }
1290 1291
1291 1292 void
1292 1293 zio_nowait(zio_t *zio)
1293 1294 {
1294 1295 ASSERT(zio->io_executor == NULL);
1295 1296
1296 1297 if (zio->io_child_type == ZIO_CHILD_LOGICAL &&
1297 1298 zio_unique_parent(zio) == NULL) {
1298 1299 /*
1299 1300 * This is a logical async I/O with no parent to wait for it.
1300 1301 * We add it to the spa_async_root_zio "Godfather" I/O which
1301 1302 * will ensure they complete prior to unloading the pool.
1302 1303 */
1303 1304 spa_t *spa = zio->io_spa;
1304 1305
1305 1306 zio_add_child(spa->spa_async_zio_root, zio);
1306 1307 }
1307 1308
1308 1309 zio_execute(zio);
1309 1310 }
1310 1311
1311 1312 /*
1312 1313 * ==========================================================================
1313 1314 * Reexecute or suspend/resume failed I/O
1314 1315 * ==========================================================================
1315 1316 */
1316 1317
1317 1318 static void
1318 1319 zio_reexecute(zio_t *pio)
1319 1320 {
1320 1321 zio_t *cio, *cio_next;
1321 1322
1322 1323 ASSERT(pio->io_child_type == ZIO_CHILD_LOGICAL);
1323 1324 ASSERT(pio->io_orig_stage == ZIO_STAGE_OPEN);
1324 1325 ASSERT(pio->io_gang_leader == NULL);
1325 1326 ASSERT(pio->io_gang_tree == NULL);
1326 1327
1327 1328 pio->io_flags = pio->io_orig_flags;
1328 1329 pio->io_stage = pio->io_orig_stage;
1329 1330 pio->io_pipeline = pio->io_orig_pipeline;
1330 1331 pio->io_reexecute = 0;
1331 1332 pio->io_flags |= ZIO_FLAG_REEXECUTED;
1332 1333 pio->io_error = 0;
1333 1334 for (int w = 0; w < ZIO_WAIT_TYPES; w++)
1334 1335 pio->io_state[w] = 0;
1335 1336 for (int c = 0; c < ZIO_CHILD_TYPES; c++)
1336 1337 pio->io_child_error[c] = 0;
1337 1338
1338 1339 if (IO_IS_ALLOCATING(pio))
1339 1340 BP_ZERO(pio->io_bp);
1340 1341
1341 1342 /*
1342 1343 * As we reexecute pio's children, new children could be created.
1343 1344 * New children go to the head of pio's io_child_list, however,
1344 1345 * so we will (correctly) not reexecute them. The key is that
1345 1346 * the remainder of pio's io_child_list, from 'cio_next' onward,
1346 1347 * cannot be affected by any side effects of reexecuting 'cio'.
1347 1348 */
1348 1349 for (cio = zio_walk_children(pio); cio != NULL; cio = cio_next) {
1349 1350 cio_next = zio_walk_children(pio);
1350 1351 mutex_enter(&pio->io_lock);
1351 1352 for (int w = 0; w < ZIO_WAIT_TYPES; w++)
1352 1353 pio->io_children[cio->io_child_type][w]++;
1353 1354 mutex_exit(&pio->io_lock);
1354 1355 zio_reexecute(cio);
1355 1356 }
1356 1357
1357 1358 /*
1358 1359 * Now that all children have been reexecuted, execute the parent.
1359 1360 * We don't reexecute "The Godfather" I/O here as it's the
1360 1361 * responsibility of the caller to wait on him.
1361 1362 */
1362 1363 if (!(pio->io_flags & ZIO_FLAG_GODFATHER))
1363 1364 zio_execute(pio);
1364 1365 }
1365 1366
1366 1367 void
1367 1368 zio_suspend(spa_t *spa, zio_t *zio)
1368 1369 {
1369 1370 if (spa_get_failmode(spa) == ZIO_FAILURE_MODE_PANIC)
1370 1371 fm_panic("Pool '%s' has encountered an uncorrectable I/O "
1371 1372 "failure and the failure mode property for this pool "
1372 1373 "is set to panic.", spa_name(spa));
1373 1374
1374 1375 zfs_ereport_post(FM_EREPORT_ZFS_IO_FAILURE, spa, NULL, NULL, 0, 0);
1375 1376
1376 1377 mutex_enter(&spa->spa_suspend_lock);
1377 1378
1378 1379 if (spa->spa_suspend_zio_root == NULL)
1379 1380 spa->spa_suspend_zio_root = zio_root(spa, NULL, NULL,
1380 1381 ZIO_FLAG_CANFAIL | ZIO_FLAG_SPECULATIVE |
1381 1382 ZIO_FLAG_GODFATHER);
1382 1383
1383 1384 spa->spa_suspended = B_TRUE;
1384 1385
1385 1386 if (zio != NULL) {
1386 1387 ASSERT(!(zio->io_flags & ZIO_FLAG_GODFATHER));
1387 1388 ASSERT(zio != spa->spa_suspend_zio_root);
1388 1389 ASSERT(zio->io_child_type == ZIO_CHILD_LOGICAL);
1389 1390 ASSERT(zio_unique_parent(zio) == NULL);
1390 1391 ASSERT(zio->io_stage == ZIO_STAGE_DONE);
1391 1392 zio_add_child(spa->spa_suspend_zio_root, zio);
1392 1393 }
1393 1394
1394 1395 mutex_exit(&spa->spa_suspend_lock);
1395 1396 }
1396 1397
1397 1398 int
1398 1399 zio_resume(spa_t *spa)
1399 1400 {
1400 1401 zio_t *pio;
1401 1402
1402 1403 /*
1403 1404 * Reexecute all previously suspended i/o.
1404 1405 */
1405 1406 mutex_enter(&spa->spa_suspend_lock);
1406 1407 spa->spa_suspended = B_FALSE;
1407 1408 cv_broadcast(&spa->spa_suspend_cv);
1408 1409 pio = spa->spa_suspend_zio_root;
1409 1410 spa->spa_suspend_zio_root = NULL;
1410 1411 mutex_exit(&spa->spa_suspend_lock);
1411 1412
1412 1413 if (pio == NULL)
1413 1414 return (0);
1414 1415
1415 1416 zio_reexecute(pio);
1416 1417 return (zio_wait(pio));
1417 1418 }
1418 1419
1419 1420 void
1420 1421 zio_resume_wait(spa_t *spa)
1421 1422 {
1422 1423 mutex_enter(&spa->spa_suspend_lock);
1423 1424 while (spa_suspended(spa))
1424 1425 cv_wait(&spa->spa_suspend_cv, &spa->spa_suspend_lock);
1425 1426 mutex_exit(&spa->spa_suspend_lock);
1426 1427 }
1427 1428
1428 1429 /*
1429 1430 * ==========================================================================
1430 1431 * Gang blocks.
1431 1432 *
1432 1433 * A gang block is a collection of small blocks that looks to the DMU
1433 1434 * like one large block. When zio_dva_allocate() cannot find a block
1434 1435 * of the requested size, due to either severe fragmentation or the pool
1435 1436 * being nearly full, it calls zio_write_gang_block() to construct the
1436 1437 * block from smaller fragments.
1437 1438 *
1438 1439 * A gang block consists of a gang header (zio_gbh_phys_t) and up to
1439 1440 * three (SPA_GBH_NBLKPTRS) gang members. The gang header is just like
1440 1441 * an indirect block: it's an array of block pointers. It consumes
1441 1442 * only one sector and hence is allocatable regardless of fragmentation.
1442 1443 * The gang header's bps point to its gang members, which hold the data.
1443 1444 *
1444 1445 * Gang blocks are self-checksumming, using the bp's <vdev, offset, txg>
1445 1446 * as the verifier to ensure uniqueness of the SHA256 checksum.
1446 1447 * Critically, the gang block bp's blk_cksum is the checksum of the data,
1447 1448 * not the gang header. This ensures that data block signatures (needed for
1448 1449 * deduplication) are independent of how the block is physically stored.
1449 1450 *
1450 1451 * Gang blocks can be nested: a gang member may itself be a gang block.
1451 1452 * Thus every gang block is a tree in which root and all interior nodes are
1452 1453 * gang headers, and the leaves are normal blocks that contain user data.
1453 1454 * The root of the gang tree is called the gang leader.
1454 1455 *
1455 1456 * To perform any operation (read, rewrite, free, claim) on a gang block,
1456 1457 * zio_gang_assemble() first assembles the gang tree (minus data leaves)
1457 1458 * in the io_gang_tree field of the original logical i/o by recursively
1458 1459 * reading the gang leader and all gang headers below it. This yields
1459 1460 * an in-core tree containing the contents of every gang header and the
1460 1461 * bps for every constituent of the gang block.
1461 1462 *
1462 1463 * With the gang tree now assembled, zio_gang_issue() just walks the gang tree
1463 1464 * and invokes a callback on each bp. To free a gang block, zio_gang_issue()
1464 1465 * calls zio_free_gang() -- a trivial wrapper around zio_free() -- for each bp.
1465 1466 * zio_claim_gang() provides a similarly trivial wrapper for zio_claim().
1466 1467 * zio_read_gang() is a wrapper around zio_read() that omits reading gang
1467 1468 * headers, since we already have those in io_gang_tree. zio_rewrite_gang()
1468 1469 * performs a zio_rewrite() of the data or, for gang headers, a zio_rewrite()
1469 1470 * of the gang header plus zio_checksum_compute() of the data to update the
1470 1471 * gang header's blk_cksum as described above.
1471 1472 *
1472 1473 * The two-phase assemble/issue model solves the problem of partial failure --
1473 1474 * what if you'd freed part of a gang block but then couldn't read the
1474 1475 * gang header for another part? Assembling the entire gang tree first
1475 1476 * ensures that all the necessary gang header I/O has succeeded before
1476 1477 * starting the actual work of free, claim, or write. Once the gang tree
1477 1478 * is assembled, free and claim are in-memory operations that cannot fail.
1478 1479 *
1479 1480 * In the event that a gang write fails, zio_dva_unallocate() walks the
1480 1481 * gang tree to immediately free (i.e. insert back into the space map)
1481 1482 * everything we've allocated. This ensures that we don't get ENOSPC
1482 1483 * errors during repeated suspend/resume cycles due to a flaky device.
1483 1484 *
1484 1485 * Gang rewrites only happen during sync-to-convergence. If we can't assemble
1485 1486 * the gang tree, we won't modify the block, so we can safely defer the free
1486 1487 * (knowing that the block is still intact). If we *can* assemble the gang
1487 1488 * tree, then even if some of the rewrites fail, zio_dva_unallocate() will free
1488 1489 * each constituent bp and we can allocate a new block on the next sync pass.
1489 1490 *
1490 1491 * In all cases, the gang tree allows complete recovery from partial failure.
1491 1492 * ==========================================================================
1492 1493 */
1493 1494
1494 1495 static zio_t *
1495 1496 zio_read_gang(zio_t *pio, blkptr_t *bp, zio_gang_node_t *gn, void *data)
1496 1497 {
1497 1498 if (gn != NULL)
1498 1499 return (pio);
1499 1500
1500 1501 return (zio_read(pio, pio->io_spa, bp, data, BP_GET_PSIZE(bp),
1501 1502 NULL, NULL, pio->io_priority, ZIO_GANG_CHILD_FLAGS(pio),
1502 1503 &pio->io_bookmark));
1503 1504 }
1504 1505
1505 1506 zio_t *
1506 1507 zio_rewrite_gang(zio_t *pio, blkptr_t *bp, zio_gang_node_t *gn, void *data)
1507 1508 {
1508 1509 zio_t *zio;
1509 1510
1510 1511 if (gn != NULL) {
1511 1512 zio = zio_rewrite(pio, pio->io_spa, pio->io_txg, bp,
1512 1513 gn->gn_gbh, SPA_GANGBLOCKSIZE, NULL, NULL, pio->io_priority,
1513 1514 ZIO_GANG_CHILD_FLAGS(pio), &pio->io_bookmark);
1514 1515 /*
1515 1516 * As we rewrite each gang header, the pipeline will compute
1516 1517 * a new gang block header checksum for it; but no one will
1517 1518 * compute a new data checksum, so we do that here. The one
1518 1519 * exception is the gang leader: the pipeline already computed
1519 1520 * its data checksum because that stage precedes gang assembly.
1520 1521 * (Presently, nothing actually uses interior data checksums;
1521 1522 * this is just good hygiene.)
1522 1523 */
1523 1524 if (gn != pio->io_gang_leader->io_gang_tree) {
1524 1525 zio_checksum_compute(zio, BP_GET_CHECKSUM(bp),
1525 1526 data, BP_GET_PSIZE(bp));
1526 1527 }
1527 1528 /*
1528 1529 * If we are here to damage data for testing purposes,
1529 1530 * leave the GBH alone so that we can detect the damage.
1530 1531 */
1531 1532 if (pio->io_gang_leader->io_flags & ZIO_FLAG_INDUCE_DAMAGE)
1532 1533 zio->io_pipeline &= ~ZIO_VDEV_IO_STAGES;
1533 1534 } else {
1534 1535 zio = zio_rewrite(pio, pio->io_spa, pio->io_txg, bp,
1535 1536 data, BP_GET_PSIZE(bp), NULL, NULL, pio->io_priority,
1536 1537 ZIO_GANG_CHILD_FLAGS(pio), &pio->io_bookmark);
1537 1538 }
1538 1539
1539 1540 return (zio);
1540 1541 }
1541 1542
1542 1543 /* ARGSUSED */
1543 1544 zio_t *
1544 1545 zio_free_gang(zio_t *pio, blkptr_t *bp, zio_gang_node_t *gn, void *data)
1545 1546 {
1546 1547 return (zio_free_sync(pio, pio->io_spa, pio->io_txg, bp,
1547 1548 ZIO_GANG_CHILD_FLAGS(pio)));
1548 1549 }
1549 1550
1550 1551 /* ARGSUSED */
1551 1552 zio_t *
1552 1553 zio_claim_gang(zio_t *pio, blkptr_t *bp, zio_gang_node_t *gn, void *data)
1553 1554 {
1554 1555 return (zio_claim(pio, pio->io_spa, pio->io_txg, bp,
1555 1556 NULL, NULL, ZIO_GANG_CHILD_FLAGS(pio)));
1556 1557 }
1557 1558
1558 1559 static zio_gang_issue_func_t *zio_gang_issue_func[ZIO_TYPES] = {
1559 1560 NULL,
1560 1561 zio_read_gang,
1561 1562 zio_rewrite_gang,
1562 1563 zio_free_gang,
1563 1564 zio_claim_gang,
1564 1565 NULL
1565 1566 };
1566 1567
1567 1568 static void zio_gang_tree_assemble_done(zio_t *zio);
1568 1569
1569 1570 static zio_gang_node_t *
1570 1571 zio_gang_node_alloc(zio_gang_node_t **gnpp)
1571 1572 {
1572 1573 zio_gang_node_t *gn;
1573 1574
1574 1575 ASSERT(*gnpp == NULL);
1575 1576
1576 1577 gn = kmem_zalloc(sizeof (*gn), KM_SLEEP);
1577 1578 gn->gn_gbh = zio_buf_alloc(SPA_GANGBLOCKSIZE);
1578 1579 *gnpp = gn;
1579 1580
1580 1581 return (gn);
1581 1582 }
1582 1583
1583 1584 static void
1584 1585 zio_gang_node_free(zio_gang_node_t **gnpp)
1585 1586 {
1586 1587 zio_gang_node_t *gn = *gnpp;
1587 1588
1588 1589 for (int g = 0; g < SPA_GBH_NBLKPTRS; g++)
1589 1590 ASSERT(gn->gn_child[g] == NULL);
1590 1591
1591 1592 zio_buf_free(gn->gn_gbh, SPA_GANGBLOCKSIZE);
1592 1593 kmem_free(gn, sizeof (*gn));
1593 1594 *gnpp = NULL;
1594 1595 }
1595 1596
1596 1597 static void
1597 1598 zio_gang_tree_free(zio_gang_node_t **gnpp)
1598 1599 {
1599 1600 zio_gang_node_t *gn = *gnpp;
1600 1601
1601 1602 if (gn == NULL)
1602 1603 return;
1603 1604
1604 1605 for (int g = 0; g < SPA_GBH_NBLKPTRS; g++)
1605 1606 zio_gang_tree_free(&gn->gn_child[g]);
1606 1607
1607 1608 zio_gang_node_free(gnpp);
1608 1609 }
1609 1610
1610 1611 static void
1611 1612 zio_gang_tree_assemble(zio_t *gio, blkptr_t *bp, zio_gang_node_t **gnpp)
1612 1613 {
1613 1614 zio_gang_node_t *gn = zio_gang_node_alloc(gnpp);
1614 1615
1615 1616 ASSERT(gio->io_gang_leader == gio);
1616 1617 ASSERT(BP_IS_GANG(bp));
1617 1618
1618 1619 zio_nowait(zio_read(gio, gio->io_spa, bp, gn->gn_gbh,
1619 1620 SPA_GANGBLOCKSIZE, zio_gang_tree_assemble_done, gn,
1620 1621 gio->io_priority, ZIO_GANG_CHILD_FLAGS(gio), &gio->io_bookmark));
1621 1622 }
1622 1623
1623 1624 static void
1624 1625 zio_gang_tree_assemble_done(zio_t *zio)
1625 1626 {
1626 1627 zio_t *gio = zio->io_gang_leader;
1627 1628 zio_gang_node_t *gn = zio->io_private;
1628 1629 blkptr_t *bp = zio->io_bp;
1629 1630
1630 1631 ASSERT(gio == zio_unique_parent(zio));
1631 1632 ASSERT(zio->io_child_count == 0);
1632 1633
1633 1634 if (zio->io_error)
1634 1635 return;
1635 1636
1636 1637 if (BP_SHOULD_BYTESWAP(bp))
1637 1638 byteswap_uint64_array(zio->io_data, zio->io_size);
1638 1639
1639 1640 ASSERT(zio->io_data == gn->gn_gbh);
1640 1641 ASSERT(zio->io_size == SPA_GANGBLOCKSIZE);
1641 1642 ASSERT(gn->gn_gbh->zg_tail.zec_magic == ZEC_MAGIC);
1642 1643
1643 1644 for (int g = 0; g < SPA_GBH_NBLKPTRS; g++) {
1644 1645 blkptr_t *gbp = &gn->gn_gbh->zg_blkptr[g];
1645 1646 if (!BP_IS_GANG(gbp))
1646 1647 continue;
1647 1648 zio_gang_tree_assemble(gio, gbp, &gn->gn_child[g]);
1648 1649 }
1649 1650 }
1650 1651
1651 1652 static void
1652 1653 zio_gang_tree_issue(zio_t *pio, zio_gang_node_t *gn, blkptr_t *bp, void *data)
1653 1654 {
1654 1655 zio_t *gio = pio->io_gang_leader;
1655 1656 zio_t *zio;
1656 1657
1657 1658 ASSERT(BP_IS_GANG(bp) == !!gn);
1658 1659 ASSERT(BP_GET_CHECKSUM(bp) == BP_GET_CHECKSUM(gio->io_bp));
1659 1660 ASSERT(BP_GET_LSIZE(bp) == BP_GET_PSIZE(bp) || gn == gio->io_gang_tree);
1660 1661
1661 1662 /*
1662 1663 * If you're a gang header, your data is in gn->gn_gbh.
1663 1664 * If you're a gang member, your data is in 'data' and gn == NULL.
1664 1665 */
1665 1666 zio = zio_gang_issue_func[gio->io_type](pio, bp, gn, data);
1666 1667
1667 1668 if (gn != NULL) {
1668 1669 ASSERT(gn->gn_gbh->zg_tail.zec_magic == ZEC_MAGIC);
1669 1670
1670 1671 for (int g = 0; g < SPA_GBH_NBLKPTRS; g++) {
1671 1672 blkptr_t *gbp = &gn->gn_gbh->zg_blkptr[g];
1672 1673 if (BP_IS_HOLE(gbp))
1673 1674 continue;
1674 1675 zio_gang_tree_issue(zio, gn->gn_child[g], gbp, data);
1675 1676 data = (char *)data + BP_GET_PSIZE(gbp);
1676 1677 }
1677 1678 }
1678 1679
1679 1680 if (gn == gio->io_gang_tree)
1680 1681 ASSERT3P((char *)gio->io_data + gio->io_size, ==, data);
1681 1682
1682 1683 if (zio != pio)
1683 1684 zio_nowait(zio);
1684 1685 }
1685 1686
1686 1687 static int
1687 1688 zio_gang_assemble(zio_t *zio)
1688 1689 {
1689 1690 blkptr_t *bp = zio->io_bp;
1690 1691
1691 1692 ASSERT(BP_IS_GANG(bp) && zio->io_gang_leader == NULL);
1692 1693 ASSERT(zio->io_child_type > ZIO_CHILD_GANG);
1693 1694
1694 1695 zio->io_gang_leader = zio;
1695 1696
1696 1697 zio_gang_tree_assemble(zio, bp, &zio->io_gang_tree);
1697 1698
1698 1699 return (ZIO_PIPELINE_CONTINUE);
1699 1700 }
1700 1701
1701 1702 static int
1702 1703 zio_gang_issue(zio_t *zio)
1703 1704 {
1704 1705 blkptr_t *bp = zio->io_bp;
1705 1706
1706 1707 if (zio_wait_for_children(zio, ZIO_CHILD_GANG, ZIO_WAIT_DONE))
1707 1708 return (ZIO_PIPELINE_STOP);
1708 1709
1709 1710 ASSERT(BP_IS_GANG(bp) && zio->io_gang_leader == zio);
1710 1711 ASSERT(zio->io_child_type > ZIO_CHILD_GANG);
1711 1712
1712 1713 if (zio->io_child_error[ZIO_CHILD_GANG] == 0)
1713 1714 zio_gang_tree_issue(zio, zio->io_gang_tree, bp, zio->io_data);
1714 1715 else
1715 1716 zio_gang_tree_free(&zio->io_gang_tree);
1716 1717
1717 1718 zio->io_pipeline = ZIO_INTERLOCK_PIPELINE;
1718 1719
1719 1720 return (ZIO_PIPELINE_CONTINUE);
1720 1721 }
1721 1722
1722 1723 static void
1723 1724 zio_write_gang_member_ready(zio_t *zio)
1724 1725 {
1725 1726 zio_t *pio = zio_unique_parent(zio);
1726 1727 zio_t *gio = zio->io_gang_leader;
1727 1728 dva_t *cdva = zio->io_bp->blk_dva;
1728 1729 dva_t *pdva = pio->io_bp->blk_dva;
1729 1730 uint64_t asize;
1730 1731
1731 1732 if (BP_IS_HOLE(zio->io_bp))
1732 1733 return;
1733 1734
1734 1735 ASSERT(BP_IS_HOLE(&zio->io_bp_orig));
1735 1736
1736 1737 ASSERT(zio->io_child_type == ZIO_CHILD_GANG);
1737 1738 ASSERT3U(zio->io_prop.zp_copies, ==, gio->io_prop.zp_copies);
1738 1739 ASSERT3U(zio->io_prop.zp_copies, <=, BP_GET_NDVAS(zio->io_bp));
1739 1740 ASSERT3U(pio->io_prop.zp_copies, <=, BP_GET_NDVAS(pio->io_bp));
1740 1741 ASSERT3U(BP_GET_NDVAS(zio->io_bp), <=, BP_GET_NDVAS(pio->io_bp));
1741 1742
1742 1743 mutex_enter(&pio->io_lock);
1743 1744 for (int d = 0; d < BP_GET_NDVAS(zio->io_bp); d++) {
1744 1745 ASSERT(DVA_GET_GANG(&pdva[d]));
1745 1746 asize = DVA_GET_ASIZE(&pdva[d]);
1746 1747 asize += DVA_GET_ASIZE(&cdva[d]);
1747 1748 DVA_SET_ASIZE(&pdva[d], asize);
1748 1749 }
1749 1750 mutex_exit(&pio->io_lock);
1750 1751 }
1751 1752
1752 1753 static int
1753 1754 zio_write_gang_block(zio_t *pio)
1754 1755 {
1755 1756 spa_t *spa = pio->io_spa;
1756 1757 blkptr_t *bp = pio->io_bp;
1757 1758 zio_t *gio = pio->io_gang_leader;
1758 1759 zio_t *zio;
1759 1760 zio_gang_node_t *gn, **gnpp;
1760 1761 zio_gbh_phys_t *gbh;
1761 1762 uint64_t txg = pio->io_txg;
1762 1763 uint64_t resid = pio->io_size;
1763 1764 uint64_t lsize;
1764 1765 int copies = gio->io_prop.zp_copies;
1765 1766 int gbh_copies = MIN(copies + 1, spa_max_replication(spa));
1766 1767 zio_prop_t zp;
1767 1768 int error;
1768 1769
1769 1770 error = metaslab_alloc(spa, spa_normal_class(spa), SPA_GANGBLOCKSIZE,
1770 1771 bp, gbh_copies, txg, pio == gio ? NULL : gio->io_bp,
1771 1772 METASLAB_HINTBP_FAVOR | METASLAB_GANG_HEADER);
1772 1773 if (error) {
1773 1774 pio->io_error = error;
1774 1775 return (ZIO_PIPELINE_CONTINUE);
1775 1776 }
1776 1777
1777 1778 if (pio == gio) {
1778 1779 gnpp = &gio->io_gang_tree;
1779 1780 } else {
1780 1781 gnpp = pio->io_private;
1781 1782 ASSERT(pio->io_ready == zio_write_gang_member_ready);
1782 1783 }
1783 1784
1784 1785 gn = zio_gang_node_alloc(gnpp);
1785 1786 gbh = gn->gn_gbh;
1786 1787 bzero(gbh, SPA_GANGBLOCKSIZE);
1787 1788
1788 1789 /*
1789 1790 * Create the gang header.
1790 1791 */
1791 1792 zio = zio_rewrite(pio, spa, txg, bp, gbh, SPA_GANGBLOCKSIZE, NULL, NULL,
1792 1793 pio->io_priority, ZIO_GANG_CHILD_FLAGS(pio), &pio->io_bookmark);
1793 1794
1794 1795 /*
1795 1796 * Create and nowait the gang children.
1796 1797 */
1797 1798 for (int g = 0; resid != 0; resid -= lsize, g++) {
1798 1799 lsize = P2ROUNDUP(resid / (SPA_GBH_NBLKPTRS - g),
1799 1800 SPA_MINBLOCKSIZE);
1800 1801 ASSERT(lsize >= SPA_MINBLOCKSIZE && lsize <= resid);
1801 1802
1802 1803 zp.zp_checksum = gio->io_prop.zp_checksum;
1803 1804 zp.zp_compress = ZIO_COMPRESS_OFF;
1804 1805 zp.zp_type = DMU_OT_NONE;
1805 1806 zp.zp_level = 0;
1806 1807 zp.zp_copies = gio->io_prop.zp_copies;
1807 1808 zp.zp_dedup = B_FALSE;
1808 1809 zp.zp_dedup_verify = B_FALSE;
1809 1810 zp.zp_nopwrite = B_FALSE;
1810 1811
1811 1812 zio_nowait(zio_write(zio, spa, txg, &gbh->zg_blkptr[g],
1812 1813 (char *)pio->io_data + (pio->io_size - resid), lsize, &zp,
1813 1814 zio_write_gang_member_ready, NULL, NULL, &gn->gn_child[g],
1814 1815 pio->io_priority, ZIO_GANG_CHILD_FLAGS(pio),
1815 1816 &pio->io_bookmark));
1816 1817 }
1817 1818
1818 1819 /*
1819 1820 * Set pio's pipeline to just wait for zio to finish.
1820 1821 */
1821 1822 pio->io_pipeline = ZIO_INTERLOCK_PIPELINE;
1822 1823
1823 1824 zio_nowait(zio);
1824 1825
1825 1826 return (ZIO_PIPELINE_CONTINUE);
1826 1827 }
1827 1828
1828 1829 /*
1829 1830 * The zio_nop_write stage in the pipeline determines if allocating
1830 1831 * a new bp is necessary. By leveraging a cryptographically secure checksum,
1831 1832 * such as SHA256, we can compare the checksums of the new data and the old
1832 1833 * to determine if allocating a new block is required. The nopwrite
1833 1834 * feature can handle writes in either syncing or open context (i.e. zil
1834 1835 * writes) and as a result is mutually exclusive with dedup.
1835 1836 */
1836 1837 static int
1837 1838 zio_nop_write(zio_t *zio)
1838 1839 {
1839 1840 blkptr_t *bp = zio->io_bp;
1840 1841 blkptr_t *bp_orig = &zio->io_bp_orig;
1841 1842 zio_prop_t *zp = &zio->io_prop;
1842 1843
1843 1844 ASSERT(BP_GET_LEVEL(bp) == 0);
1844 1845 ASSERT(!(zio->io_flags & ZIO_FLAG_IO_REWRITE));
1845 1846 ASSERT(zp->zp_nopwrite);
1846 1847 ASSERT(!zp->zp_dedup);
1847 1848 ASSERT(zio->io_bp_override == NULL);
1848 1849 ASSERT(IO_IS_ALLOCATING(zio));
1849 1850
1850 1851 /*
1851 1852 * Check to see if the original bp and the new bp have matching
1852 1853 * characteristics (i.e. same checksum, compression algorithms, etc).
1853 1854 * If they don't then just continue with the pipeline which will
1854 1855 * allocate a new bp.
1855 1856 */
1856 1857 if (BP_IS_HOLE(bp_orig) ||
1857 1858 !zio_checksum_table[BP_GET_CHECKSUM(bp)].ci_dedup ||
1858 1859 BP_GET_CHECKSUM(bp) != BP_GET_CHECKSUM(bp_orig) ||
1859 1860 BP_GET_COMPRESS(bp) != BP_GET_COMPRESS(bp_orig) ||
1860 1861 BP_GET_DEDUP(bp) != BP_GET_DEDUP(bp_orig) ||
1861 1862 zp->zp_copies != BP_GET_NDVAS(bp_orig))
1862 1863 return (ZIO_PIPELINE_CONTINUE);
1863 1864
1864 1865 /*
1865 1866 * If the checksums match then reset the pipeline so that we
1866 1867 * avoid allocating a new bp and issuing any I/O.
1867 1868 */
1868 1869 if (ZIO_CHECKSUM_EQUAL(bp->blk_cksum, bp_orig->blk_cksum)) {
1869 1870 ASSERT(zio_checksum_table[zp->zp_checksum].ci_dedup);
1870 1871 ASSERT3U(BP_GET_PSIZE(bp), ==, BP_GET_PSIZE(bp_orig));
1871 1872 ASSERT3U(BP_GET_LSIZE(bp), ==, BP_GET_LSIZE(bp_orig));
1872 1873 ASSERT(zp->zp_compress != ZIO_COMPRESS_OFF);
1873 1874 ASSERT(bcmp(&bp->blk_prop, &bp_orig->blk_prop,
1874 1875 sizeof (uint64_t)) == 0);
1875 1876
1876 1877 *bp = *bp_orig;
1877 1878 zio->io_pipeline = ZIO_INTERLOCK_PIPELINE;
1878 1879 zio->io_flags |= ZIO_FLAG_NOPWRITE;
1879 1880 }
1880 1881
1881 1882 return (ZIO_PIPELINE_CONTINUE);
1882 1883 }
1883 1884
1884 1885 /*
1885 1886 * ==========================================================================
1886 1887 * Dedup
1887 1888 * ==========================================================================
1888 1889 */
1889 1890 static void
1890 1891 zio_ddt_child_read_done(zio_t *zio)
1891 1892 {
1892 1893 blkptr_t *bp = zio->io_bp;
1893 1894 ddt_entry_t *dde = zio->io_private;
1894 1895 ddt_phys_t *ddp;
1895 1896 zio_t *pio = zio_unique_parent(zio);
1896 1897
1897 1898 mutex_enter(&pio->io_lock);
1898 1899 ddp = ddt_phys_select(dde, bp);
1899 1900 if (zio->io_error == 0)
1900 1901 ddt_phys_clear(ddp); /* this ddp doesn't need repair */
1901 1902 if (zio->io_error == 0 && dde->dde_repair_data == NULL)
1902 1903 dde->dde_repair_data = zio->io_data;
1903 1904 else
1904 1905 zio_buf_free(zio->io_data, zio->io_size);
1905 1906 mutex_exit(&pio->io_lock);
1906 1907 }
1907 1908
1908 1909 static int
1909 1910 zio_ddt_read_start(zio_t *zio)
1910 1911 {
1911 1912 blkptr_t *bp = zio->io_bp;
1912 1913
1913 1914 ASSERT(BP_GET_DEDUP(bp));
1914 1915 ASSERT(BP_GET_PSIZE(bp) == zio->io_size);
1915 1916 ASSERT(zio->io_child_type == ZIO_CHILD_LOGICAL);
1916 1917
1917 1918 if (zio->io_child_error[ZIO_CHILD_DDT]) {
1918 1919 ddt_t *ddt = ddt_select(zio->io_spa, bp);
1919 1920 ddt_entry_t *dde = ddt_repair_start(ddt, bp);
1920 1921 ddt_phys_t *ddp = dde->dde_phys;
1921 1922 ddt_phys_t *ddp_self = ddt_phys_select(dde, bp);
1922 1923 blkptr_t blk;
1923 1924
1924 1925 ASSERT(zio->io_vsd == NULL);
1925 1926 zio->io_vsd = dde;
1926 1927
1927 1928 if (ddp_self == NULL)
1928 1929 return (ZIO_PIPELINE_CONTINUE);
1929 1930
1930 1931 for (int p = 0; p < DDT_PHYS_TYPES; p++, ddp++) {
1931 1932 if (ddp->ddp_phys_birth == 0 || ddp == ddp_self)
1932 1933 continue;
1933 1934 ddt_bp_create(ddt->ddt_checksum, &dde->dde_key, ddp,
1934 1935 &blk);
1935 1936 zio_nowait(zio_read(zio, zio->io_spa, &blk,
1936 1937 zio_buf_alloc(zio->io_size), zio->io_size,
1937 1938 zio_ddt_child_read_done, dde, zio->io_priority,
1938 1939 ZIO_DDT_CHILD_FLAGS(zio) | ZIO_FLAG_DONT_PROPAGATE,
1939 1940 &zio->io_bookmark));
1940 1941 }
1941 1942 return (ZIO_PIPELINE_CONTINUE);
1942 1943 }
1943 1944
1944 1945 zio_nowait(zio_read(zio, zio->io_spa, bp,
1945 1946 zio->io_data, zio->io_size, NULL, NULL, zio->io_priority,
1946 1947 ZIO_DDT_CHILD_FLAGS(zio), &zio->io_bookmark));
1947 1948
1948 1949 return (ZIO_PIPELINE_CONTINUE);
1949 1950 }
1950 1951
1951 1952 static int
1952 1953 zio_ddt_read_done(zio_t *zio)
1953 1954 {
1954 1955 blkptr_t *bp = zio->io_bp;
1955 1956
1956 1957 if (zio_wait_for_children(zio, ZIO_CHILD_DDT, ZIO_WAIT_DONE))
1957 1958 return (ZIO_PIPELINE_STOP);
1958 1959
1959 1960 ASSERT(BP_GET_DEDUP(bp));
1960 1961 ASSERT(BP_GET_PSIZE(bp) == zio->io_size);
1961 1962 ASSERT(zio->io_child_type == ZIO_CHILD_LOGICAL);
1962 1963
1963 1964 if (zio->io_child_error[ZIO_CHILD_DDT]) {
1964 1965 ddt_t *ddt = ddt_select(zio->io_spa, bp);
1965 1966 ddt_entry_t *dde = zio->io_vsd;
1966 1967 if (ddt == NULL) {
1967 1968 ASSERT(spa_load_state(zio->io_spa) != SPA_LOAD_NONE);
1968 1969 return (ZIO_PIPELINE_CONTINUE);
1969 1970 }
1970 1971 if (dde == NULL) {
1971 1972 zio->io_stage = ZIO_STAGE_DDT_READ_START >> 1;
1972 1973 zio_taskq_dispatch(zio, ZIO_TASKQ_ISSUE, B_FALSE);
1973 1974 return (ZIO_PIPELINE_STOP);
1974 1975 }
1975 1976 if (dde->dde_repair_data != NULL) {
1976 1977 bcopy(dde->dde_repair_data, zio->io_data, zio->io_size);
1977 1978 zio->io_child_error[ZIO_CHILD_DDT] = 0;
1978 1979 }
1979 1980 ddt_repair_done(ddt, dde);
1980 1981 zio->io_vsd = NULL;
1981 1982 }
1982 1983
1983 1984 ASSERT(zio->io_vsd == NULL);
1984 1985
1985 1986 return (ZIO_PIPELINE_CONTINUE);
1986 1987 }
1987 1988
1988 1989 static boolean_t
1989 1990 zio_ddt_collision(zio_t *zio, ddt_t *ddt, ddt_entry_t *dde)
1990 1991 {
1991 1992 spa_t *spa = zio->io_spa;
1992 1993
1993 1994 /*
1994 1995 * Note: we compare the original data, not the transformed data,
1995 1996 * because when zio->io_bp is an override bp, we will not have
1996 1997 * pushed the I/O transforms. That's an important optimization
1997 1998 * because otherwise we'd compress/encrypt all dmu_sync() data twice.
1998 1999 */
1999 2000 for (int p = DDT_PHYS_SINGLE; p <= DDT_PHYS_TRIPLE; p++) {
2000 2001 zio_t *lio = dde->dde_lead_zio[p];
2001 2002
2002 2003 if (lio != NULL) {
2003 2004 return (lio->io_orig_size != zio->io_orig_size ||
2004 2005 bcmp(zio->io_orig_data, lio->io_orig_data,
2005 2006 zio->io_orig_size) != 0);
2006 2007 }
2007 2008 }
2008 2009
2009 2010 for (int p = DDT_PHYS_SINGLE; p <= DDT_PHYS_TRIPLE; p++) {
2010 2011 ddt_phys_t *ddp = &dde->dde_phys[p];
2011 2012
2012 2013 if (ddp->ddp_phys_birth != 0) {
2013 2014 arc_buf_t *abuf = NULL;
2014 2015 uint32_t aflags = ARC_WAIT;
2015 2016 blkptr_t blk = *zio->io_bp;
2016 2017 int error;
2017 2018
2018 2019 ddt_bp_fill(ddp, &blk, ddp->ddp_phys_birth);
2019 2020
2020 2021 ddt_exit(ddt);
2021 2022
2022 2023 error = arc_read(NULL, spa, &blk,
2023 2024 arc_getbuf_func, &abuf, ZIO_PRIORITY_SYNC_READ,
2024 2025 ZIO_FLAG_CANFAIL | ZIO_FLAG_SPECULATIVE,
2025 2026 &aflags, &zio->io_bookmark);
2026 2027
2027 2028 if (error == 0) {
2028 2029 if (arc_buf_size(abuf) != zio->io_orig_size ||
2029 2030 bcmp(abuf->b_data, zio->io_orig_data,
2030 2031 zio->io_orig_size) != 0)
2031 2032 error = SET_ERROR(EEXIST);
2032 2033 VERIFY(arc_buf_remove_ref(abuf, &abuf));
2033 2034 }
2034 2035
2035 2036 ddt_enter(ddt);
2036 2037 return (error != 0);
2037 2038 }
2038 2039 }
2039 2040
2040 2041 return (B_FALSE);
2041 2042 }
2042 2043
2043 2044 static void
2044 2045 zio_ddt_child_write_ready(zio_t *zio)
2045 2046 {
2046 2047 int p = zio->io_prop.zp_copies;
2047 2048 ddt_t *ddt = ddt_select(zio->io_spa, zio->io_bp);
2048 2049 ddt_entry_t *dde = zio->io_private;
2049 2050 ddt_phys_t *ddp = &dde->dde_phys[p];
2050 2051 zio_t *pio;
2051 2052
2052 2053 if (zio->io_error)
2053 2054 return;
2054 2055
2055 2056 ddt_enter(ddt);
2056 2057
2057 2058 ASSERT(dde->dde_lead_zio[p] == zio);
2058 2059
2059 2060 ddt_phys_fill(ddp, zio->io_bp);
2060 2061
2061 2062 while ((pio = zio_walk_parents(zio)) != NULL)
2062 2063 ddt_bp_fill(ddp, pio->io_bp, zio->io_txg);
2063 2064
2064 2065 ddt_exit(ddt);
2065 2066 }
2066 2067
2067 2068 static void
2068 2069 zio_ddt_child_write_done(zio_t *zio)
2069 2070 {
2070 2071 int p = zio->io_prop.zp_copies;
2071 2072 ddt_t *ddt = ddt_select(zio->io_spa, zio->io_bp);
2072 2073 ddt_entry_t *dde = zio->io_private;
2073 2074 ddt_phys_t *ddp = &dde->dde_phys[p];
2074 2075
2075 2076 ddt_enter(ddt);
2076 2077
2077 2078 ASSERT(ddp->ddp_refcnt == 0);
2078 2079 ASSERT(dde->dde_lead_zio[p] == zio);
2079 2080 dde->dde_lead_zio[p] = NULL;
2080 2081
2081 2082 if (zio->io_error == 0) {
2082 2083 while (zio_walk_parents(zio) != NULL)
2083 2084 ddt_phys_addref(ddp);
2084 2085 } else {
2085 2086 ddt_phys_clear(ddp);
2086 2087 }
2087 2088
2088 2089 ddt_exit(ddt);
2089 2090 }
2090 2091
2091 2092 static void
2092 2093 zio_ddt_ditto_write_done(zio_t *zio)
2093 2094 {
2094 2095 int p = DDT_PHYS_DITTO;
2095 2096 zio_prop_t *zp = &zio->io_prop;
2096 2097 blkptr_t *bp = zio->io_bp;
2097 2098 ddt_t *ddt = ddt_select(zio->io_spa, bp);
2098 2099 ddt_entry_t *dde = zio->io_private;
2099 2100 ddt_phys_t *ddp = &dde->dde_phys[p];
2100 2101 ddt_key_t *ddk = &dde->dde_key;
2101 2102
2102 2103 ddt_enter(ddt);
2103 2104
2104 2105 ASSERT(ddp->ddp_refcnt == 0);
2105 2106 ASSERT(dde->dde_lead_zio[p] == zio);
2106 2107 dde->dde_lead_zio[p] = NULL;
2107 2108
2108 2109 if (zio->io_error == 0) {
2109 2110 ASSERT(ZIO_CHECKSUM_EQUAL(bp->blk_cksum, ddk->ddk_cksum));
2110 2111 ASSERT(zp->zp_copies < SPA_DVAS_PER_BP);
2111 2112 ASSERT(zp->zp_copies == BP_GET_NDVAS(bp) - BP_IS_GANG(bp));
2112 2113 if (ddp->ddp_phys_birth != 0)
2113 2114 ddt_phys_free(ddt, ddk, ddp, zio->io_txg);
2114 2115 ddt_phys_fill(ddp, bp);
2115 2116 }
2116 2117
2117 2118 ddt_exit(ddt);
2118 2119 }
2119 2120
2120 2121 static int
2121 2122 zio_ddt_write(zio_t *zio)
2122 2123 {
2123 2124 spa_t *spa = zio->io_spa;
2124 2125 blkptr_t *bp = zio->io_bp;
2125 2126 uint64_t txg = zio->io_txg;
2126 2127 zio_prop_t *zp = &zio->io_prop;
2127 2128 int p = zp->zp_copies;
2128 2129 int ditto_copies;
2129 2130 zio_t *cio = NULL;
2130 2131 zio_t *dio = NULL;
2131 2132 ddt_t *ddt = ddt_select(spa, bp);
2132 2133 ddt_entry_t *dde;
2133 2134 ddt_phys_t *ddp;
2134 2135
2135 2136 ASSERT(BP_GET_DEDUP(bp));
2136 2137 ASSERT(BP_GET_CHECKSUM(bp) == zp->zp_checksum);
2137 2138 ASSERT(BP_IS_HOLE(bp) || zio->io_bp_override);
2138 2139
2139 2140 ddt_enter(ddt);
2140 2141 dde = ddt_lookup(ddt, bp, B_TRUE);
2141 2142 ddp = &dde->dde_phys[p];
2142 2143
2143 2144 if (zp->zp_dedup_verify && zio_ddt_collision(zio, ddt, dde)) {
2144 2145 /*
2145 2146 * If we're using a weak checksum, upgrade to a strong checksum
2146 2147 * and try again. If we're already using a strong checksum,
2147 2148 * we can't resolve it, so just convert to an ordinary write.
2148 2149 * (And automatically e-mail a paper to Nature?)
2149 2150 */
2150 2151 if (!zio_checksum_table[zp->zp_checksum].ci_dedup) {
2151 2152 zp->zp_checksum = spa_dedup_checksum(spa);
2152 2153 zio_pop_transforms(zio);
2153 2154 zio->io_stage = ZIO_STAGE_OPEN;
2154 2155 BP_ZERO(bp);
2155 2156 } else {
2156 2157 zp->zp_dedup = B_FALSE;
2157 2158 }
2158 2159 zio->io_pipeline = ZIO_WRITE_PIPELINE;
2159 2160 ddt_exit(ddt);
2160 2161 return (ZIO_PIPELINE_CONTINUE);
2161 2162 }
2162 2163
2163 2164 ditto_copies = ddt_ditto_copies_needed(ddt, dde, ddp);
2164 2165 ASSERT(ditto_copies < SPA_DVAS_PER_BP);
2165 2166
2166 2167 if (ditto_copies > ddt_ditto_copies_present(dde) &&
2167 2168 dde->dde_lead_zio[DDT_PHYS_DITTO] == NULL) {
2168 2169 zio_prop_t czp = *zp;
2169 2170
2170 2171 czp.zp_copies = ditto_copies;
2171 2172
2172 2173 /*
2173 2174 * If we arrived here with an override bp, we won't have run
2174 2175 * the transform stack, so we won't have the data we need to
2175 2176 * generate a child i/o. So, toss the override bp and restart.
2176 2177 * This is safe, because using the override bp is just an
2177 2178 * optimization; and it's rare, so the cost doesn't matter.
2178 2179 */
2179 2180 if (zio->io_bp_override) {
2180 2181 zio_pop_transforms(zio);
2181 2182 zio->io_stage = ZIO_STAGE_OPEN;
2182 2183 zio->io_pipeline = ZIO_WRITE_PIPELINE;
2183 2184 zio->io_bp_override = NULL;
2184 2185 BP_ZERO(bp);
2185 2186 ddt_exit(ddt);
2186 2187 return (ZIO_PIPELINE_CONTINUE);
2187 2188 }
2188 2189
2189 2190 dio = zio_write(zio, spa, txg, bp, zio->io_orig_data,
2190 2191 zio->io_orig_size, &czp, NULL, NULL,
2191 2192 zio_ddt_ditto_write_done, dde, zio->io_priority,
2192 2193 ZIO_DDT_CHILD_FLAGS(zio), &zio->io_bookmark);
2193 2194
2194 2195 zio_push_transform(dio, zio->io_data, zio->io_size, 0, NULL);
2195 2196 dde->dde_lead_zio[DDT_PHYS_DITTO] = dio;
2196 2197 }
2197 2198
2198 2199 if (ddp->ddp_phys_birth != 0 || dde->dde_lead_zio[p] != NULL) {
2199 2200 if (ddp->ddp_phys_birth != 0)
2200 2201 ddt_bp_fill(ddp, bp, txg);
2201 2202 if (dde->dde_lead_zio[p] != NULL)
2202 2203 zio_add_child(zio, dde->dde_lead_zio[p]);
2203 2204 else
2204 2205 ddt_phys_addref(ddp);
2205 2206 } else if (zio->io_bp_override) {
2206 2207 ASSERT(bp->blk_birth == txg);
2207 2208 ASSERT(BP_EQUAL(bp, zio->io_bp_override));
2208 2209 ddt_phys_fill(ddp, bp);
2209 2210 ddt_phys_addref(ddp);
2210 2211 } else {
2211 2212 cio = zio_write(zio, spa, txg, bp, zio->io_orig_data,
2212 2213 zio->io_orig_size, zp, zio_ddt_child_write_ready, NULL,
2213 2214 zio_ddt_child_write_done, dde, zio->io_priority,
2214 2215 ZIO_DDT_CHILD_FLAGS(zio), &zio->io_bookmark);
2215 2216
2216 2217 zio_push_transform(cio, zio->io_data, zio->io_size, 0, NULL);
2217 2218 dde->dde_lead_zio[p] = cio;
2218 2219 }
2219 2220
2220 2221 ddt_exit(ddt);
2221 2222
2222 2223 if (cio)
2223 2224 zio_nowait(cio);
2224 2225 if (dio)
2225 2226 zio_nowait(dio);
2226 2227
2227 2228 return (ZIO_PIPELINE_CONTINUE);
2228 2229 }
2229 2230
2230 2231 ddt_entry_t *freedde; /* for debugging */
2231 2232
2232 2233 static int
2233 2234 zio_ddt_free(zio_t *zio)
2234 2235 {
2235 2236 spa_t *spa = zio->io_spa;
2236 2237 blkptr_t *bp = zio->io_bp;
2237 2238 ddt_t *ddt = ddt_select(spa, bp);
2238 2239 ddt_entry_t *dde;
2239 2240 ddt_phys_t *ddp;
2240 2241
2241 2242 ASSERT(BP_GET_DEDUP(bp));
2242 2243 ASSERT(zio->io_child_type == ZIO_CHILD_LOGICAL);
2243 2244
2244 2245 ddt_enter(ddt);
2245 2246 freedde = dde = ddt_lookup(ddt, bp, B_TRUE);
2246 2247 ddp = ddt_phys_select(dde, bp);
2247 2248 ddt_phys_decref(ddp);
2248 2249 ddt_exit(ddt);
2249 2250
2250 2251 return (ZIO_PIPELINE_CONTINUE);
2251 2252 }
2252 2253
2253 2254 /*
2254 2255 * ==========================================================================
2255 2256 * Allocate and free blocks
2256 2257 * ==========================================================================
2257 2258 */
2258 2259 static int
2259 2260 zio_dva_allocate(zio_t *zio)
2260 2261 {
2261 2262 spa_t *spa = zio->io_spa;
2262 2263 metaslab_class_t *mc = spa_normal_class(spa);
2263 2264 blkptr_t *bp = zio->io_bp;
2264 2265 int error;
2265 2266 int flags = 0;
2266 2267
2267 2268 if (zio->io_gang_leader == NULL) {
2268 2269 ASSERT(zio->io_child_type > ZIO_CHILD_GANG);
2269 2270 zio->io_gang_leader = zio;
2270 2271 }
2271 2272
2272 2273 ASSERT(BP_IS_HOLE(bp));
2273 2274 ASSERT0(BP_GET_NDVAS(bp));
2274 2275 ASSERT3U(zio->io_prop.zp_copies, >, 0);
2275 2276 ASSERT3U(zio->io_prop.zp_copies, <=, spa_max_replication(spa));
2276 2277 ASSERT3U(zio->io_size, ==, BP_GET_PSIZE(bp));
2277 2278
2278 2279 /*
2279 2280 * The dump device does not support gang blocks so allocation on
2280 2281 * behalf of the dump device (i.e. ZIO_FLAG_NODATA) must avoid
2281 2282 * the "fast" gang feature.
2282 2283 */
2283 2284 flags |= (zio->io_flags & ZIO_FLAG_NODATA) ? METASLAB_GANG_AVOID : 0;
2284 2285 flags |= (zio->io_flags & ZIO_FLAG_GANG_CHILD) ?
2285 2286 METASLAB_GANG_CHILD : 0;
2286 2287 error = metaslab_alloc(spa, mc, zio->io_size, bp,
2287 2288 zio->io_prop.zp_copies, zio->io_txg, NULL, flags);
2288 2289
2289 2290 if (error) {
2290 2291 spa_dbgmsg(spa, "%s: metaslab allocation failure: zio %p, "
2291 2292 "size %llu, error %d", spa_name(spa), zio, zio->io_size,
2292 2293 error);
2293 2294 if (error == ENOSPC && zio->io_size > SPA_MINBLOCKSIZE)
2294 2295 return (zio_write_gang_block(zio));
2295 2296 zio->io_error = error;
2296 2297 }
2297 2298
2298 2299 return (ZIO_PIPELINE_CONTINUE);
2299 2300 }
2300 2301
2301 2302 static int
2302 2303 zio_dva_free(zio_t *zio)
2303 2304 {
2304 2305 metaslab_free(zio->io_spa, zio->io_bp, zio->io_txg, B_FALSE);
2305 2306
2306 2307 return (ZIO_PIPELINE_CONTINUE);
2307 2308 }
2308 2309
2309 2310 static int
2310 2311 zio_dva_claim(zio_t *zio)
2311 2312 {
2312 2313 int error;
2313 2314
2314 2315 error = metaslab_claim(zio->io_spa, zio->io_bp, zio->io_txg);
2315 2316 if (error)
2316 2317 zio->io_error = error;
2317 2318
2318 2319 return (ZIO_PIPELINE_CONTINUE);
2319 2320 }
2320 2321
2321 2322 /*
2322 2323 * Undo an allocation. This is used by zio_done() when an I/O fails
2323 2324 * and we want to give back the block we just allocated.
2324 2325 * This handles both normal blocks and gang blocks.
2325 2326 */
2326 2327 static void
2327 2328 zio_dva_unallocate(zio_t *zio, zio_gang_node_t *gn, blkptr_t *bp)
2328 2329 {
2329 2330 ASSERT(bp->blk_birth == zio->io_txg || BP_IS_HOLE(bp));
2330 2331 ASSERT(zio->io_bp_override == NULL);
2331 2332
2332 2333 if (!BP_IS_HOLE(bp))
2333 2334 metaslab_free(zio->io_spa, bp, bp->blk_birth, B_TRUE);
2334 2335
2335 2336 if (gn != NULL) {
2336 2337 for (int g = 0; g < SPA_GBH_NBLKPTRS; g++) {
2337 2338 zio_dva_unallocate(zio, gn->gn_child[g],
2338 2339 &gn->gn_gbh->zg_blkptr[g]);
2339 2340 }
2340 2341 }
2341 2342 }
2342 2343
2343 2344 /*
2344 2345 * Try to allocate an intent log block. Return 0 on success, errno on failure.
2345 2346 */
2346 2347 int
2347 2348 zio_alloc_zil(spa_t *spa, uint64_t txg, blkptr_t *new_bp, blkptr_t *old_bp,
2348 2349 uint64_t size, boolean_t use_slog)
2349 2350 {
2350 2351 int error = 1;
2351 2352
2352 2353 ASSERT(txg > spa_syncing_txg(spa));
2353 2354
2354 2355 /*
2355 2356 * ZIL blocks are always contiguous (i.e. not gang blocks) so we
2356 2357 * set the METASLAB_GANG_AVOID flag so that they don't "fast gang"
2357 2358 * when allocating them.
|
↓ open down ↓ |
2173 lines elided |
↑ open up ↑ |
2358 2359 */
2359 2360 if (use_slog) {
2360 2361 error = metaslab_alloc(spa, spa_log_class(spa), size,
2361 2362 new_bp, 1, txg, old_bp,
2362 2363 METASLAB_HINTBP_AVOID | METASLAB_GANG_AVOID);
2363 2364 }
2364 2365
2365 2366 if (error) {
2366 2367 error = metaslab_alloc(spa, spa_normal_class(spa), size,
2367 2368 new_bp, 1, txg, old_bp,
2368 - METASLAB_HINTBP_AVOID | METASLAB_GANG_AVOID);
2369 + METASLAB_HINTBP_AVOID);
2369 2370 }
2370 2371
2371 2372 if (error == 0) {
2372 2373 BP_SET_LSIZE(new_bp, size);
2373 2374 BP_SET_PSIZE(new_bp, size);
2374 2375 BP_SET_COMPRESS(new_bp, ZIO_COMPRESS_OFF);
2375 2376 BP_SET_CHECKSUM(new_bp,
2376 2377 spa_version(spa) >= SPA_VERSION_SLIM_ZIL
2377 2378 ? ZIO_CHECKSUM_ZILOG2 : ZIO_CHECKSUM_ZILOG);
2378 2379 BP_SET_TYPE(new_bp, DMU_OT_INTENT_LOG);
2379 2380 BP_SET_LEVEL(new_bp, 0);
2380 2381 BP_SET_DEDUP(new_bp, 0);
2381 2382 BP_SET_BYTEORDER(new_bp, ZFS_HOST_BYTEORDER);
2382 2383 }
2383 2384
2384 2385 return (error);
2385 2386 }
2386 2387
2387 2388 /*
2388 2389 * Free an intent log block.
2389 2390 */
2390 2391 void
2391 2392 zio_free_zil(spa_t *spa, uint64_t txg, blkptr_t *bp)
2392 2393 {
2393 2394 ASSERT(BP_GET_TYPE(bp) == DMU_OT_INTENT_LOG);
2394 2395 ASSERT(!BP_IS_GANG(bp));
2395 2396
2396 2397 zio_free(spa, txg, bp);
2397 2398 }
2398 2399
2399 2400 /*
2400 2401 * ==========================================================================
2401 2402 * Read and write to physical devices
2402 2403 * ==========================================================================
2403 2404 */
2404 2405 static int
2405 2406 zio_vdev_io_start(zio_t *zio)
2406 2407 {
2407 2408 vdev_t *vd = zio->io_vd;
2408 2409 uint64_t align;
2409 2410 spa_t *spa = zio->io_spa;
2410 2411
2411 2412 ASSERT(zio->io_error == 0);
2412 2413 ASSERT(zio->io_child_error[ZIO_CHILD_VDEV] == 0);
2413 2414
2414 2415 if (vd == NULL) {
2415 2416 if (!(zio->io_flags & ZIO_FLAG_CONFIG_WRITER))
2416 2417 spa_config_enter(spa, SCL_ZIO, zio, RW_READER);
2417 2418
2418 2419 /*
2419 2420 * The mirror_ops handle multiple DVAs in a single BP.
2420 2421 */
2421 2422 return (vdev_mirror_ops.vdev_op_io_start(zio));
2422 2423 }
2423 2424
2424 2425 /*
2425 2426 * We keep track of time-sensitive I/Os so that the scan thread
2426 2427 * can quickly react to certain workloads. In particular, we care
2427 2428 * about non-scrubbing, top-level reads and writes with the following
2428 2429 * characteristics:
2429 2430 * - synchronous writes of user data to non-slog devices
2430 2431 * - any reads of user data
2431 2432 * When these conditions are met, adjust the timestamp of spa_last_io
2432 2433 * which allows the scan thread to adjust its workload accordingly.
2433 2434 */
2434 2435 if (!(zio->io_flags & ZIO_FLAG_SCAN_THREAD) && zio->io_bp != NULL &&
2435 2436 vd == vd->vdev_top && !vd->vdev_islog &&
2436 2437 zio->io_bookmark.zb_objset != DMU_META_OBJSET &&
2437 2438 zio->io_txg != spa_syncing_txg(spa)) {
2438 2439 uint64_t old = spa->spa_last_io;
2439 2440 uint64_t new = ddi_get_lbolt64();
2440 2441 if (old != new)
2441 2442 (void) atomic_cas_64(&spa->spa_last_io, old, new);
2442 2443 }
2443 2444
2444 2445 align = 1ULL << vd->vdev_top->vdev_ashift;
2445 2446
2446 2447 if (P2PHASE(zio->io_size, align) != 0) {
2447 2448 uint64_t asize = P2ROUNDUP(zio->io_size, align);
2448 2449 char *abuf = zio_buf_alloc(asize);
2449 2450 ASSERT(vd == vd->vdev_top);
2450 2451 if (zio->io_type == ZIO_TYPE_WRITE) {
2451 2452 bcopy(zio->io_data, abuf, zio->io_size);
2452 2453 bzero(abuf + zio->io_size, asize - zio->io_size);
2453 2454 }
2454 2455 zio_push_transform(zio, abuf, asize, asize, zio_subblock);
2455 2456 }
2456 2457
2457 2458 ASSERT(P2PHASE(zio->io_offset, align) == 0);
2458 2459 ASSERT(P2PHASE(zio->io_size, align) == 0);
2459 2460 VERIFY(zio->io_type != ZIO_TYPE_WRITE || spa_writeable(spa));
2460 2461
2461 2462 /*
2462 2463 * If this is a repair I/O, and there's no self-healing involved --
2463 2464 * that is, we're just resilvering what we expect to resilver --
2464 2465 * then don't do the I/O unless zio's txg is actually in vd's DTL.
2465 2466 * This prevents spurious resilvering with nested replication.
2466 2467 * For example, given a mirror of mirrors, (A+B)+(C+D), if only
2467 2468 * A is out of date, we'll read from C+D, then use the data to
2468 2469 * resilver A+B -- but we don't actually want to resilver B, just A.
2469 2470 * The top-level mirror has no way to know this, so instead we just
2470 2471 * discard unnecessary repairs as we work our way down the vdev tree.
2471 2472 * The same logic applies to any form of nested replication:
2472 2473 * ditto + mirror, RAID-Z + replacing, etc. This covers them all.
2473 2474 */
2474 2475 if ((zio->io_flags & ZIO_FLAG_IO_REPAIR) &&
2475 2476 !(zio->io_flags & ZIO_FLAG_SELF_HEAL) &&
2476 2477 zio->io_txg != 0 && /* not a delegated i/o */
2477 2478 !vdev_dtl_contains(vd, DTL_PARTIAL, zio->io_txg, 1)) {
2478 2479 ASSERT(zio->io_type == ZIO_TYPE_WRITE);
2479 2480 zio_vdev_io_bypass(zio);
2480 2481 return (ZIO_PIPELINE_CONTINUE);
2481 2482 }
2482 2483
2483 2484 if (vd->vdev_ops->vdev_op_leaf &&
2484 2485 (zio->io_type == ZIO_TYPE_READ || zio->io_type == ZIO_TYPE_WRITE)) {
2485 2486
2486 2487 if (zio->io_type == ZIO_TYPE_READ && vdev_cache_read(zio) == 0)
2487 2488 return (ZIO_PIPELINE_CONTINUE);
2488 2489
2489 2490 if ((zio = vdev_queue_io(zio)) == NULL)
2490 2491 return (ZIO_PIPELINE_STOP);
2491 2492
2492 2493 if (!vdev_accessible(vd, zio)) {
2493 2494 zio->io_error = SET_ERROR(ENXIO);
2494 2495 zio_interrupt(zio);
2495 2496 return (ZIO_PIPELINE_STOP);
2496 2497 }
2497 2498 }
2498 2499
2499 2500 return (vd->vdev_ops->vdev_op_io_start(zio));
2500 2501 }
2501 2502
2502 2503 static int
2503 2504 zio_vdev_io_done(zio_t *zio)
2504 2505 {
2505 2506 vdev_t *vd = zio->io_vd;
2506 2507 vdev_ops_t *ops = vd ? vd->vdev_ops : &vdev_mirror_ops;
2507 2508 boolean_t unexpected_error = B_FALSE;
2508 2509
2509 2510 if (zio_wait_for_children(zio, ZIO_CHILD_VDEV, ZIO_WAIT_DONE))
2510 2511 return (ZIO_PIPELINE_STOP);
2511 2512
2512 2513 ASSERT(zio->io_type == ZIO_TYPE_READ || zio->io_type == ZIO_TYPE_WRITE);
2513 2514
2514 2515 if (vd != NULL && vd->vdev_ops->vdev_op_leaf) {
2515 2516
2516 2517 vdev_queue_io_done(zio);
2517 2518
2518 2519 if (zio->io_type == ZIO_TYPE_WRITE)
2519 2520 vdev_cache_write(zio);
2520 2521
2521 2522 if (zio_injection_enabled && zio->io_error == 0)
2522 2523 zio->io_error = zio_handle_device_injection(vd,
2523 2524 zio, EIO);
2524 2525
2525 2526 if (zio_injection_enabled && zio->io_error == 0)
2526 2527 zio->io_error = zio_handle_label_injection(zio, EIO);
2527 2528
2528 2529 if (zio->io_error) {
2529 2530 if (!vdev_accessible(vd, zio)) {
2530 2531 zio->io_error = SET_ERROR(ENXIO);
2531 2532 } else {
2532 2533 unexpected_error = B_TRUE;
2533 2534 }
2534 2535 }
2535 2536 }
2536 2537
2537 2538 ops->vdev_op_io_done(zio);
2538 2539
2539 2540 if (unexpected_error)
2540 2541 VERIFY(vdev_probe(vd, zio) == NULL);
2541 2542
2542 2543 return (ZIO_PIPELINE_CONTINUE);
2543 2544 }
2544 2545
2545 2546 /*
2546 2547 * For non-raidz ZIOs, we can just copy aside the bad data read from the
2547 2548 * disk, and use that to finish the checksum ereport later.
2548 2549 */
2549 2550 static void
2550 2551 zio_vsd_default_cksum_finish(zio_cksum_report_t *zcr,
2551 2552 const void *good_buf)
2552 2553 {
2553 2554 /* no processing needed */
2554 2555 zfs_ereport_finish_checksum(zcr, good_buf, zcr->zcr_cbdata, B_FALSE);
2555 2556 }
2556 2557
2557 2558 /*ARGSUSED*/
2558 2559 void
2559 2560 zio_vsd_default_cksum_report(zio_t *zio, zio_cksum_report_t *zcr, void *ignored)
2560 2561 {
2561 2562 void *buf = zio_buf_alloc(zio->io_size);
2562 2563
2563 2564 bcopy(zio->io_data, buf, zio->io_size);
2564 2565
2565 2566 zcr->zcr_cbinfo = zio->io_size;
2566 2567 zcr->zcr_cbdata = buf;
2567 2568 zcr->zcr_finish = zio_vsd_default_cksum_finish;
2568 2569 zcr->zcr_free = zio_buf_free;
2569 2570 }
2570 2571
2571 2572 static int
2572 2573 zio_vdev_io_assess(zio_t *zio)
2573 2574 {
2574 2575 vdev_t *vd = zio->io_vd;
2575 2576
2576 2577 if (zio_wait_for_children(zio, ZIO_CHILD_VDEV, ZIO_WAIT_DONE))
2577 2578 return (ZIO_PIPELINE_STOP);
2578 2579
2579 2580 if (vd == NULL && !(zio->io_flags & ZIO_FLAG_CONFIG_WRITER))
2580 2581 spa_config_exit(zio->io_spa, SCL_ZIO, zio);
2581 2582
2582 2583 if (zio->io_vsd != NULL) {
2583 2584 zio->io_vsd_ops->vsd_free(zio);
2584 2585 zio->io_vsd = NULL;
2585 2586 }
2586 2587
2587 2588 if (zio_injection_enabled && zio->io_error == 0)
2588 2589 zio->io_error = zio_handle_fault_injection(zio, EIO);
2589 2590
2590 2591 /*
2591 2592 * If the I/O failed, determine whether we should attempt to retry it.
2592 2593 *
2593 2594 * On retry, we cut in line in the issue queue, since we don't want
2594 2595 * compression/checksumming/etc. work to prevent our (cheap) IO reissue.
2595 2596 */
2596 2597 if (zio->io_error && vd == NULL &&
2597 2598 !(zio->io_flags & (ZIO_FLAG_DONT_RETRY | ZIO_FLAG_IO_RETRY))) {
2598 2599 ASSERT(!(zio->io_flags & ZIO_FLAG_DONT_QUEUE)); /* not a leaf */
2599 2600 ASSERT(!(zio->io_flags & ZIO_FLAG_IO_BYPASS)); /* not a leaf */
2600 2601 zio->io_error = 0;
2601 2602 zio->io_flags |= ZIO_FLAG_IO_RETRY |
2602 2603 ZIO_FLAG_DONT_CACHE | ZIO_FLAG_DONT_AGGREGATE;
2603 2604 zio->io_stage = ZIO_STAGE_VDEV_IO_START >> 1;
2604 2605 zio_taskq_dispatch(zio, ZIO_TASKQ_ISSUE,
2605 2606 zio_requeue_io_start_cut_in_line);
2606 2607 return (ZIO_PIPELINE_STOP);
2607 2608 }
2608 2609
2609 2610 /*
2610 2611 * If we got an error on a leaf device, convert it to ENXIO
2611 2612 * if the device is not accessible at all.
2612 2613 */
2613 2614 if (zio->io_error && vd != NULL && vd->vdev_ops->vdev_op_leaf &&
2614 2615 !vdev_accessible(vd, zio))
2615 2616 zio->io_error = SET_ERROR(ENXIO);
2616 2617
2617 2618 /*
2618 2619 * If we can't write to an interior vdev (mirror or RAID-Z),
2619 2620 * set vdev_cant_write so that we stop trying to allocate from it.
2620 2621 */
2621 2622 if (zio->io_error == ENXIO && zio->io_type == ZIO_TYPE_WRITE &&
2622 2623 vd != NULL && !vd->vdev_ops->vdev_op_leaf) {
2623 2624 vd->vdev_cant_write = B_TRUE;
2624 2625 }
2625 2626
2626 2627 if (zio->io_error)
2627 2628 zio->io_pipeline = ZIO_INTERLOCK_PIPELINE;
2628 2629
2629 2630 if (vd != NULL && vd->vdev_ops->vdev_op_leaf &&
2630 2631 zio->io_physdone != NULL) {
2631 2632 ASSERT(!(zio->io_flags & ZIO_FLAG_DELEGATED));
2632 2633 ASSERT(zio->io_child_type == ZIO_CHILD_VDEV);
2633 2634 zio->io_physdone(zio->io_logical);
2634 2635 }
2635 2636
2636 2637 return (ZIO_PIPELINE_CONTINUE);
2637 2638 }
2638 2639
2639 2640 void
2640 2641 zio_vdev_io_reissue(zio_t *zio)
2641 2642 {
2642 2643 ASSERT(zio->io_stage == ZIO_STAGE_VDEV_IO_START);
2643 2644 ASSERT(zio->io_error == 0);
2644 2645
2645 2646 zio->io_stage >>= 1;
2646 2647 }
2647 2648
2648 2649 void
2649 2650 zio_vdev_io_redone(zio_t *zio)
2650 2651 {
2651 2652 ASSERT(zio->io_stage == ZIO_STAGE_VDEV_IO_DONE);
2652 2653
2653 2654 zio->io_stage >>= 1;
2654 2655 }
2655 2656
2656 2657 void
2657 2658 zio_vdev_io_bypass(zio_t *zio)
2658 2659 {
2659 2660 ASSERT(zio->io_stage == ZIO_STAGE_VDEV_IO_START);
2660 2661 ASSERT(zio->io_error == 0);
2661 2662
2662 2663 zio->io_flags |= ZIO_FLAG_IO_BYPASS;
2663 2664 zio->io_stage = ZIO_STAGE_VDEV_IO_ASSESS >> 1;
2664 2665 }
2665 2666
2666 2667 /*
2667 2668 * ==========================================================================
2668 2669 * Generate and verify checksums
2669 2670 * ==========================================================================
2670 2671 */
2671 2672 static int
2672 2673 zio_checksum_generate(zio_t *zio)
2673 2674 {
2674 2675 blkptr_t *bp = zio->io_bp;
2675 2676 enum zio_checksum checksum;
2676 2677
2677 2678 if (bp == NULL) {
2678 2679 /*
2679 2680 * This is zio_write_phys().
2680 2681 * We're either generating a label checksum, or none at all.
2681 2682 */
2682 2683 checksum = zio->io_prop.zp_checksum;
2683 2684
2684 2685 if (checksum == ZIO_CHECKSUM_OFF)
2685 2686 return (ZIO_PIPELINE_CONTINUE);
2686 2687
2687 2688 ASSERT(checksum == ZIO_CHECKSUM_LABEL);
2688 2689 } else {
2689 2690 if (BP_IS_GANG(bp) && zio->io_child_type == ZIO_CHILD_GANG) {
2690 2691 ASSERT(!IO_IS_ALLOCATING(zio));
2691 2692 checksum = ZIO_CHECKSUM_GANG_HEADER;
2692 2693 } else {
2693 2694 checksum = BP_GET_CHECKSUM(bp);
2694 2695 }
2695 2696 }
2696 2697
2697 2698 zio_checksum_compute(zio, checksum, zio->io_data, zio->io_size);
2698 2699
2699 2700 return (ZIO_PIPELINE_CONTINUE);
2700 2701 }
2701 2702
2702 2703 static int
2703 2704 zio_checksum_verify(zio_t *zio)
2704 2705 {
2705 2706 zio_bad_cksum_t info;
2706 2707 blkptr_t *bp = zio->io_bp;
2707 2708 int error;
2708 2709
2709 2710 ASSERT(zio->io_vd != NULL);
2710 2711
2711 2712 if (bp == NULL) {
2712 2713 /*
2713 2714 * This is zio_read_phys().
2714 2715 * We're either verifying a label checksum, or nothing at all.
2715 2716 */
2716 2717 if (zio->io_prop.zp_checksum == ZIO_CHECKSUM_OFF)
2717 2718 return (ZIO_PIPELINE_CONTINUE);
2718 2719
2719 2720 ASSERT(zio->io_prop.zp_checksum == ZIO_CHECKSUM_LABEL);
2720 2721 }
2721 2722
2722 2723 if ((error = zio_checksum_error(zio, &info)) != 0) {
2723 2724 zio->io_error = error;
2724 2725 if (!(zio->io_flags & ZIO_FLAG_SPECULATIVE)) {
2725 2726 zfs_ereport_start_checksum(zio->io_spa,
2726 2727 zio->io_vd, zio, zio->io_offset,
2727 2728 zio->io_size, NULL, &info);
2728 2729 }
2729 2730 }
2730 2731
2731 2732 return (ZIO_PIPELINE_CONTINUE);
2732 2733 }
2733 2734
2734 2735 /*
2735 2736 * Called by RAID-Z to ensure we don't compute the checksum twice.
2736 2737 */
2737 2738 void
2738 2739 zio_checksum_verified(zio_t *zio)
2739 2740 {
2740 2741 zio->io_pipeline &= ~ZIO_STAGE_CHECKSUM_VERIFY;
2741 2742 }
2742 2743
2743 2744 /*
2744 2745 * ==========================================================================
2745 2746 * Error rank. Error are ranked in the order 0, ENXIO, ECKSUM, EIO, other.
2746 2747 * An error of 0 indictes success. ENXIO indicates whole-device failure,
2747 2748 * which may be transient (e.g. unplugged) or permament. ECKSUM and EIO
2748 2749 * indicate errors that are specific to one I/O, and most likely permanent.
2749 2750 * Any other error is presumed to be worse because we weren't expecting it.
2750 2751 * ==========================================================================
2751 2752 */
2752 2753 int
2753 2754 zio_worst_error(int e1, int e2)
2754 2755 {
2755 2756 static int zio_error_rank[] = { 0, ENXIO, ECKSUM, EIO };
2756 2757 int r1, r2;
2757 2758
2758 2759 for (r1 = 0; r1 < sizeof (zio_error_rank) / sizeof (int); r1++)
2759 2760 if (e1 == zio_error_rank[r1])
2760 2761 break;
2761 2762
2762 2763 for (r2 = 0; r2 < sizeof (zio_error_rank) / sizeof (int); r2++)
2763 2764 if (e2 == zio_error_rank[r2])
2764 2765 break;
2765 2766
2766 2767 return (r1 > r2 ? e1 : e2);
2767 2768 }
2768 2769
2769 2770 /*
2770 2771 * ==========================================================================
2771 2772 * I/O completion
2772 2773 * ==========================================================================
2773 2774 */
2774 2775 static int
2775 2776 zio_ready(zio_t *zio)
2776 2777 {
2777 2778 blkptr_t *bp = zio->io_bp;
2778 2779 zio_t *pio, *pio_next;
2779 2780
2780 2781 if (zio_wait_for_children(zio, ZIO_CHILD_GANG, ZIO_WAIT_READY) ||
2781 2782 zio_wait_for_children(zio, ZIO_CHILD_DDT, ZIO_WAIT_READY))
2782 2783 return (ZIO_PIPELINE_STOP);
2783 2784
2784 2785 if (zio->io_ready) {
2785 2786 ASSERT(IO_IS_ALLOCATING(zio));
2786 2787 ASSERT(bp->blk_birth == zio->io_txg || BP_IS_HOLE(bp) ||
2787 2788 (zio->io_flags & ZIO_FLAG_NOPWRITE));
2788 2789 ASSERT(zio->io_children[ZIO_CHILD_GANG][ZIO_WAIT_READY] == 0);
2789 2790
2790 2791 zio->io_ready(zio);
2791 2792 }
2792 2793
2793 2794 if (bp != NULL && bp != &zio->io_bp_copy)
2794 2795 zio->io_bp_copy = *bp;
2795 2796
2796 2797 if (zio->io_error)
2797 2798 zio->io_pipeline = ZIO_INTERLOCK_PIPELINE;
2798 2799
2799 2800 mutex_enter(&zio->io_lock);
2800 2801 zio->io_state[ZIO_WAIT_READY] = 1;
2801 2802 pio = zio_walk_parents(zio);
2802 2803 mutex_exit(&zio->io_lock);
2803 2804
2804 2805 /*
2805 2806 * As we notify zio's parents, new parents could be added.
2806 2807 * New parents go to the head of zio's io_parent_list, however,
2807 2808 * so we will (correctly) not notify them. The remainder of zio's
2808 2809 * io_parent_list, from 'pio_next' onward, cannot change because
2809 2810 * all parents must wait for us to be done before they can be done.
2810 2811 */
2811 2812 for (; pio != NULL; pio = pio_next) {
2812 2813 pio_next = zio_walk_parents(zio);
2813 2814 zio_notify_parent(pio, zio, ZIO_WAIT_READY);
2814 2815 }
2815 2816
2816 2817 if (zio->io_flags & ZIO_FLAG_NODATA) {
2817 2818 if (BP_IS_GANG(bp)) {
2818 2819 zio->io_flags &= ~ZIO_FLAG_NODATA;
2819 2820 } else {
2820 2821 ASSERT((uintptr_t)zio->io_data < SPA_MAXBLOCKSIZE);
2821 2822 zio->io_pipeline &= ~ZIO_VDEV_IO_STAGES;
2822 2823 }
2823 2824 }
2824 2825
2825 2826 if (zio_injection_enabled &&
2826 2827 zio->io_spa->spa_syncing_txg == zio->io_txg)
2827 2828 zio_handle_ignored_writes(zio);
2828 2829
2829 2830 return (ZIO_PIPELINE_CONTINUE);
2830 2831 }
2831 2832
2832 2833 static int
2833 2834 zio_done(zio_t *zio)
2834 2835 {
2835 2836 spa_t *spa = zio->io_spa;
2836 2837 zio_t *lio = zio->io_logical;
2837 2838 blkptr_t *bp = zio->io_bp;
2838 2839 vdev_t *vd = zio->io_vd;
2839 2840 uint64_t psize = zio->io_size;
2840 2841 zio_t *pio, *pio_next;
2841 2842
2842 2843 /*
2843 2844 * If our children haven't all completed,
2844 2845 * wait for them and then repeat this pipeline stage.
2845 2846 */
2846 2847 if (zio_wait_for_children(zio, ZIO_CHILD_VDEV, ZIO_WAIT_DONE) ||
2847 2848 zio_wait_for_children(zio, ZIO_CHILD_GANG, ZIO_WAIT_DONE) ||
2848 2849 zio_wait_for_children(zio, ZIO_CHILD_DDT, ZIO_WAIT_DONE) ||
2849 2850 zio_wait_for_children(zio, ZIO_CHILD_LOGICAL, ZIO_WAIT_DONE))
2850 2851 return (ZIO_PIPELINE_STOP);
2851 2852
2852 2853 for (int c = 0; c < ZIO_CHILD_TYPES; c++)
2853 2854 for (int w = 0; w < ZIO_WAIT_TYPES; w++)
2854 2855 ASSERT(zio->io_children[c][w] == 0);
2855 2856
2856 2857 if (bp != NULL) {
2857 2858 ASSERT(bp->blk_pad[0] == 0);
2858 2859 ASSERT(bp->blk_pad[1] == 0);
2859 2860 ASSERT(bcmp(bp, &zio->io_bp_copy, sizeof (blkptr_t)) == 0 ||
2860 2861 (bp == zio_unique_parent(zio)->io_bp));
2861 2862 if (zio->io_type == ZIO_TYPE_WRITE && !BP_IS_HOLE(bp) &&
2862 2863 zio->io_bp_override == NULL &&
2863 2864 !(zio->io_flags & ZIO_FLAG_IO_REPAIR)) {
2864 2865 ASSERT(!BP_SHOULD_BYTESWAP(bp));
2865 2866 ASSERT3U(zio->io_prop.zp_copies, <=, BP_GET_NDVAS(bp));
2866 2867 ASSERT(BP_COUNT_GANG(bp) == 0 ||
2867 2868 (BP_COUNT_GANG(bp) == BP_GET_NDVAS(bp)));
2868 2869 }
2869 2870 if (zio->io_flags & ZIO_FLAG_NOPWRITE)
2870 2871 VERIFY(BP_EQUAL(bp, &zio->io_bp_orig));
2871 2872 }
2872 2873
2873 2874 /*
2874 2875 * If there were child vdev/gang/ddt errors, they apply to us now.
2875 2876 */
2876 2877 zio_inherit_child_errors(zio, ZIO_CHILD_VDEV);
2877 2878 zio_inherit_child_errors(zio, ZIO_CHILD_GANG);
2878 2879 zio_inherit_child_errors(zio, ZIO_CHILD_DDT);
2879 2880
2880 2881 /*
2881 2882 * If the I/O on the transformed data was successful, generate any
2882 2883 * checksum reports now while we still have the transformed data.
2883 2884 */
2884 2885 if (zio->io_error == 0) {
2885 2886 while (zio->io_cksum_report != NULL) {
2886 2887 zio_cksum_report_t *zcr = zio->io_cksum_report;
2887 2888 uint64_t align = zcr->zcr_align;
2888 2889 uint64_t asize = P2ROUNDUP(psize, align);
2889 2890 char *abuf = zio->io_data;
2890 2891
2891 2892 if (asize != psize) {
2892 2893 abuf = zio_buf_alloc(asize);
2893 2894 bcopy(zio->io_data, abuf, psize);
2894 2895 bzero(abuf + psize, asize - psize);
2895 2896 }
2896 2897
2897 2898 zio->io_cksum_report = zcr->zcr_next;
2898 2899 zcr->zcr_next = NULL;
2899 2900 zcr->zcr_finish(zcr, abuf);
2900 2901 zfs_ereport_free_checksum(zcr);
2901 2902
2902 2903 if (asize != psize)
2903 2904 zio_buf_free(abuf, asize);
2904 2905 }
2905 2906 }
2906 2907
2907 2908 zio_pop_transforms(zio); /* note: may set zio->io_error */
2908 2909
2909 2910 vdev_stat_update(zio, psize);
2910 2911
2911 2912 if (zio->io_error) {
2912 2913 /*
2913 2914 * If this I/O is attached to a particular vdev,
2914 2915 * generate an error message describing the I/O failure
2915 2916 * at the block level. We ignore these errors if the
2916 2917 * device is currently unavailable.
2917 2918 */
2918 2919 if (zio->io_error != ECKSUM && vd != NULL && !vdev_is_dead(vd))
2919 2920 zfs_ereport_post(FM_EREPORT_ZFS_IO, spa, vd, zio, 0, 0);
2920 2921
2921 2922 if ((zio->io_error == EIO || !(zio->io_flags &
2922 2923 (ZIO_FLAG_SPECULATIVE | ZIO_FLAG_DONT_PROPAGATE))) &&
2923 2924 zio == lio) {
2924 2925 /*
2925 2926 * For logical I/O requests, tell the SPA to log the
2926 2927 * error and generate a logical data ereport.
2927 2928 */
2928 2929 spa_log_error(spa, zio);
2929 2930 zfs_ereport_post(FM_EREPORT_ZFS_DATA, spa, NULL, zio,
2930 2931 0, 0);
2931 2932 }
2932 2933 }
2933 2934
2934 2935 if (zio->io_error && zio == lio) {
2935 2936 /*
2936 2937 * Determine whether zio should be reexecuted. This will
2937 2938 * propagate all the way to the root via zio_notify_parent().
2938 2939 */
2939 2940 ASSERT(vd == NULL && bp != NULL);
2940 2941 ASSERT(zio->io_child_type == ZIO_CHILD_LOGICAL);
2941 2942
2942 2943 if (IO_IS_ALLOCATING(zio) &&
2943 2944 !(zio->io_flags & ZIO_FLAG_CANFAIL)) {
2944 2945 if (zio->io_error != ENOSPC)
2945 2946 zio->io_reexecute |= ZIO_REEXECUTE_NOW;
2946 2947 else
2947 2948 zio->io_reexecute |= ZIO_REEXECUTE_SUSPEND;
2948 2949 }
2949 2950
2950 2951 if ((zio->io_type == ZIO_TYPE_READ ||
2951 2952 zio->io_type == ZIO_TYPE_FREE) &&
2952 2953 !(zio->io_flags & ZIO_FLAG_SCAN_THREAD) &&
2953 2954 zio->io_error == ENXIO &&
2954 2955 spa_load_state(spa) == SPA_LOAD_NONE &&
2955 2956 spa_get_failmode(spa) != ZIO_FAILURE_MODE_CONTINUE)
2956 2957 zio->io_reexecute |= ZIO_REEXECUTE_SUSPEND;
2957 2958
2958 2959 if (!(zio->io_flags & ZIO_FLAG_CANFAIL) && !zio->io_reexecute)
2959 2960 zio->io_reexecute |= ZIO_REEXECUTE_SUSPEND;
2960 2961
2961 2962 /*
2962 2963 * Here is a possibly good place to attempt to do
2963 2964 * either combinatorial reconstruction or error correction
2964 2965 * based on checksums. It also might be a good place
2965 2966 * to send out preliminary ereports before we suspend
2966 2967 * processing.
2967 2968 */
2968 2969 }
2969 2970
2970 2971 /*
2971 2972 * If there were logical child errors, they apply to us now.
2972 2973 * We defer this until now to avoid conflating logical child
2973 2974 * errors with errors that happened to the zio itself when
2974 2975 * updating vdev stats and reporting FMA events above.
2975 2976 */
2976 2977 zio_inherit_child_errors(zio, ZIO_CHILD_LOGICAL);
2977 2978
2978 2979 if ((zio->io_error || zio->io_reexecute) &&
2979 2980 IO_IS_ALLOCATING(zio) && zio->io_gang_leader == zio &&
2980 2981 !(zio->io_flags & (ZIO_FLAG_IO_REWRITE | ZIO_FLAG_NOPWRITE)))
2981 2982 zio_dva_unallocate(zio, zio->io_gang_tree, bp);
2982 2983
2983 2984 zio_gang_tree_free(&zio->io_gang_tree);
2984 2985
2985 2986 /*
2986 2987 * Godfather I/Os should never suspend.
2987 2988 */
2988 2989 if ((zio->io_flags & ZIO_FLAG_GODFATHER) &&
2989 2990 (zio->io_reexecute & ZIO_REEXECUTE_SUSPEND))
2990 2991 zio->io_reexecute = 0;
2991 2992
2992 2993 if (zio->io_reexecute) {
2993 2994 /*
2994 2995 * This is a logical I/O that wants to reexecute.
2995 2996 *
2996 2997 * Reexecute is top-down. When an i/o fails, if it's not
2997 2998 * the root, it simply notifies its parent and sticks around.
2998 2999 * The parent, seeing that it still has children in zio_done(),
2999 3000 * does the same. This percolates all the way up to the root.
3000 3001 * The root i/o will reexecute or suspend the entire tree.
3001 3002 *
3002 3003 * This approach ensures that zio_reexecute() honors
3003 3004 * all the original i/o dependency relationships, e.g.
3004 3005 * parents not executing until children are ready.
3005 3006 */
3006 3007 ASSERT(zio->io_child_type == ZIO_CHILD_LOGICAL);
3007 3008
3008 3009 zio->io_gang_leader = NULL;
3009 3010
3010 3011 mutex_enter(&zio->io_lock);
3011 3012 zio->io_state[ZIO_WAIT_DONE] = 1;
3012 3013 mutex_exit(&zio->io_lock);
3013 3014
3014 3015 /*
3015 3016 * "The Godfather" I/O monitors its children but is
3016 3017 * not a true parent to them. It will track them through
3017 3018 * the pipeline but severs its ties whenever they get into
3018 3019 * trouble (e.g. suspended). This allows "The Godfather"
3019 3020 * I/O to return status without blocking.
3020 3021 */
3021 3022 for (pio = zio_walk_parents(zio); pio != NULL; pio = pio_next) {
3022 3023 zio_link_t *zl = zio->io_walk_link;
3023 3024 pio_next = zio_walk_parents(zio);
3024 3025
3025 3026 if ((pio->io_flags & ZIO_FLAG_GODFATHER) &&
3026 3027 (zio->io_reexecute & ZIO_REEXECUTE_SUSPEND)) {
3027 3028 zio_remove_child(pio, zio, zl);
3028 3029 zio_notify_parent(pio, zio, ZIO_WAIT_DONE);
3029 3030 }
3030 3031 }
3031 3032
3032 3033 if ((pio = zio_unique_parent(zio)) != NULL) {
3033 3034 /*
3034 3035 * We're not a root i/o, so there's nothing to do
3035 3036 * but notify our parent. Don't propagate errors
3036 3037 * upward since we haven't permanently failed yet.
3037 3038 */
3038 3039 ASSERT(!(zio->io_flags & ZIO_FLAG_GODFATHER));
3039 3040 zio->io_flags |= ZIO_FLAG_DONT_PROPAGATE;
3040 3041 zio_notify_parent(pio, zio, ZIO_WAIT_DONE);
3041 3042 } else if (zio->io_reexecute & ZIO_REEXECUTE_SUSPEND) {
3042 3043 /*
3043 3044 * We'd fail again if we reexecuted now, so suspend
3044 3045 * until conditions improve (e.g. device comes online).
3045 3046 */
3046 3047 zio_suspend(spa, zio);
3047 3048 } else {
3048 3049 /*
3049 3050 * Reexecution is potentially a huge amount of work.
3050 3051 * Hand it off to the otherwise-unused claim taskq.
3051 3052 */
3052 3053 ASSERT(zio->io_tqent.tqent_next == NULL);
3053 3054 spa_taskq_dispatch_ent(spa, ZIO_TYPE_CLAIM,
3054 3055 ZIO_TASKQ_ISSUE, (task_func_t *)zio_reexecute, zio,
3055 3056 0, &zio->io_tqent);
3056 3057 }
3057 3058 return (ZIO_PIPELINE_STOP);
3058 3059 }
3059 3060
3060 3061 ASSERT(zio->io_child_count == 0);
3061 3062 ASSERT(zio->io_reexecute == 0);
3062 3063 ASSERT(zio->io_error == 0 || (zio->io_flags & ZIO_FLAG_CANFAIL));
3063 3064
3064 3065 /*
3065 3066 * Report any checksum errors, since the I/O is complete.
3066 3067 */
3067 3068 while (zio->io_cksum_report != NULL) {
3068 3069 zio_cksum_report_t *zcr = zio->io_cksum_report;
3069 3070 zio->io_cksum_report = zcr->zcr_next;
3070 3071 zcr->zcr_next = NULL;
3071 3072 zcr->zcr_finish(zcr, NULL);
3072 3073 zfs_ereport_free_checksum(zcr);
3073 3074 }
3074 3075
3075 3076 /*
3076 3077 * It is the responsibility of the done callback to ensure that this
3077 3078 * particular zio is no longer discoverable for adoption, and as
3078 3079 * such, cannot acquire any new parents.
3079 3080 */
3080 3081 if (zio->io_done)
3081 3082 zio->io_done(zio);
3082 3083
3083 3084 mutex_enter(&zio->io_lock);
3084 3085 zio->io_state[ZIO_WAIT_DONE] = 1;
3085 3086 mutex_exit(&zio->io_lock);
3086 3087
3087 3088 for (pio = zio_walk_parents(zio); pio != NULL; pio = pio_next) {
3088 3089 zio_link_t *zl = zio->io_walk_link;
3089 3090 pio_next = zio_walk_parents(zio);
3090 3091 zio_remove_child(pio, zio, zl);
3091 3092 zio_notify_parent(pio, zio, ZIO_WAIT_DONE);
3092 3093 }
3093 3094
3094 3095 if (zio->io_waiter != NULL) {
3095 3096 mutex_enter(&zio->io_lock);
3096 3097 zio->io_executor = NULL;
3097 3098 cv_broadcast(&zio->io_cv);
3098 3099 mutex_exit(&zio->io_lock);
3099 3100 } else {
3100 3101 zio_destroy(zio);
3101 3102 }
3102 3103
3103 3104 return (ZIO_PIPELINE_STOP);
3104 3105 }
3105 3106
3106 3107 /*
3107 3108 * ==========================================================================
3108 3109 * I/O pipeline definition
3109 3110 * ==========================================================================
3110 3111 */
3111 3112 static zio_pipe_stage_t *zio_pipeline[] = {
3112 3113 NULL,
3113 3114 zio_read_bp_init,
3114 3115 zio_free_bp_init,
3115 3116 zio_issue_async,
3116 3117 zio_write_bp_init,
3117 3118 zio_checksum_generate,
3118 3119 zio_nop_write,
3119 3120 zio_ddt_read_start,
3120 3121 zio_ddt_read_done,
3121 3122 zio_ddt_write,
3122 3123 zio_ddt_free,
3123 3124 zio_gang_assemble,
3124 3125 zio_gang_issue,
3125 3126 zio_dva_allocate,
3126 3127 zio_dva_free,
3127 3128 zio_dva_claim,
3128 3129 zio_ready,
3129 3130 zio_vdev_io_start,
3130 3131 zio_vdev_io_done,
3131 3132 zio_vdev_io_assess,
3132 3133 zio_checksum_verify,
3133 3134 zio_done
3134 3135 };
3135 3136
3136 3137 /* dnp is the dnode for zb1->zb_object */
3137 3138 boolean_t
3138 3139 zbookmark_is_before(const dnode_phys_t *dnp, const zbookmark_t *zb1,
3139 3140 const zbookmark_t *zb2)
3140 3141 {
3141 3142 uint64_t zb1nextL0, zb2thisobj;
3142 3143
3143 3144 ASSERT(zb1->zb_objset == zb2->zb_objset);
3144 3145 ASSERT(zb2->zb_level == 0);
3145 3146
3146 3147 /*
3147 3148 * A bookmark in the deadlist is considered to be after
3148 3149 * everything else.
3149 3150 */
3150 3151 if (zb2->zb_object == DMU_DEADLIST_OBJECT)
3151 3152 return (B_TRUE);
3152 3153
3153 3154 /* The objset_phys_t isn't before anything. */
3154 3155 if (dnp == NULL)
3155 3156 return (B_FALSE);
3156 3157
3157 3158 zb1nextL0 = (zb1->zb_blkid + 1) <<
3158 3159 ((zb1->zb_level) * (dnp->dn_indblkshift - SPA_BLKPTRSHIFT));
3159 3160
3160 3161 zb2thisobj = zb2->zb_object ? zb2->zb_object :
3161 3162 zb2->zb_blkid << (DNODE_BLOCK_SHIFT - DNODE_SHIFT);
3162 3163
3163 3164 if (zb1->zb_object == DMU_META_DNODE_OBJECT) {
3164 3165 uint64_t nextobj = zb1nextL0 *
3165 3166 (dnp->dn_datablkszsec << SPA_MINBLOCKSHIFT) >> DNODE_SHIFT;
3166 3167 return (nextobj <= zb2thisobj);
3167 3168 }
3168 3169
3169 3170 if (zb1->zb_object < zb2thisobj)
3170 3171 return (B_TRUE);
3171 3172 if (zb1->zb_object > zb2thisobj)
3172 3173 return (B_FALSE);
3173 3174 if (zb2->zb_object == DMU_META_DNODE_OBJECT)
3174 3175 return (B_FALSE);
3175 3176 return (zb1nextL0 <= zb2->zb_blkid);
3176 3177 }
|
↓ open down ↓ |
798 lines elided |
↑ open up ↑ |
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX