4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
23 * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
24 * Copyright (c) 2012, 2015 by Delphix. All rights reserved.
28 * Virtual Device Labels
29 * ---------------------
31 * The vdev label serves several distinct purposes:
33 * 1. Uniquely identify this device as part of a ZFS pool and confirm its
34 * identity within the pool.
36 * 2. Verify that all the devices given in a configuration are present
39 * 3. Determine the uberblock for the pool.
41 * 4. In case of an import operation, determine the configuration of the
42 * toplevel vdev of which it is a part.
44 * 5. If an import operation cannot find all the devices in the pool,
45 * provide enough information to the administrator to determine which
46 * devices are missing.
48 * It is important to note that while the kernel is responsible for writing the
49 * label, it only consumes the information in the first three cases. The
50 * latter information is only consumed in userland when determining the
51 * configuration to import a pool.
57 * Before describing the contents of the label, it's important to understand how
58 * the labels are written and updated with respect to the uberblock.
60 * When the pool configuration is altered, either because it was newly created
61 * or a device was added, we want to update all the labels such that we can deal
62 * with fatal failure at any point. To this end, each disk has two labels which
63 * are updated before and after the uberblock is synced. Assuming we have
64 * labels and an uberblock with the following transaction groups:
67 * +------+ +------+ +------+
69 * | t10 | | t10 | | t10 |
71 * +------+ +------+ +------+
73 * In this stable state, the labels and the uberblock were all updated within
74 * the same transaction group (10). Each label is mirrored and checksummed, so
75 * that we can detect when we fail partway through writing the label.
77 * In order to identify which labels are valid, the labels are written in the
80 * 1. For each vdev, update 'L1' to the new label
81 * 2. Update the uberblock
82 * 3. For each vdev, update 'L2' to the new label
84 * Given arbitrary failure, we can determine the correct label to use based on
85 * the transaction group. If we fail after updating L1 but before updating the
86 * UB, we will notice that L1's transaction group is greater than the uberblock,
87 * so L2 must be valid. If we fail after writing the uberblock but before
88 * writing L2, we will notice that L2's transaction group is less than L1, and
89 * therefore L1 is valid.
91 * Another added complexity is that not every label is updated when the config
92 * is synced. If we add a single device, we do not want to have to re-write
93 * every label for every device in the pool. This means that both L1 and L2 may
94 * be older than the pool uberblock, because the necessary information is stored
101 * The vdev label consists of two distinct parts, and is wrapped within the
102 * vdev_label_t structure. The label includes 8k of padding to permit legacy
103 * VTOC disk labels, but is otherwise ignored.
105 * The first half of the label is a packed nvlist which contains pool wide
106 * properties, per-vdev properties, and configuration information. It is
107 * described in more detail below.
109 * The latter half of the label consists of a redundant array of uberblocks.
110 * These uberblocks are updated whenever a transaction group is committed,
111 * or when the configuration is updated. When a pool is loaded, we scan each
112 * vdev for the 'best' uberblock.
115 * Configuration Information
116 * -------------------------
118 * The nvlist describing the pool and vdev contains the following elements:
120 * version ZFS on-disk version
123 * txg Transaction group in which this label was written
124 * pool_guid Unique identifier for this pool
125 * vdev_tree An nvlist describing vdev tree.
127 * An nvlist of the features necessary for reading the MOS.
129 * Each leaf device label also contains the following:
131 * top_guid Unique ID for top-level vdev in which this is contained
132 * guid Unique ID for the leaf vdev
134 * The 'vs' configuration follows the format described in 'spa_config.c'.
137 #include <sys/zfs_context.h>
139 #include <sys/spa_impl.h>
142 #include <sys/vdev.h>
143 #include <sys/vdev_impl.h>
144 #include <sys/uberblock_impl.h>
145 #include <sys/metaslab.h>
147 #include <sys/dsl_scan.h>
149 #include <sys/fs/zfs.h>
152 * Basic routines to read and write from a vdev label.
153 * Used throughout the rest of this file.
156 vdev_label_offset(uint64_t psize
, int l
, uint64_t offset
)
158 ASSERT(offset
< sizeof (vdev_label_t
));
159 ASSERT(P2PHASE_TYPED(psize
, sizeof (vdev_label_t
), uint64_t) == 0);
161 return (offset
+ l
* sizeof (vdev_label_t
) + (l
< VDEV_LABELS
/ 2 ?
162 0 : psize
- VDEV_LABELS
* sizeof (vdev_label_t
)));
166 * Returns back the vdev label associated with the passed in offset.
169 vdev_label_number(uint64_t psize
, uint64_t offset
)
173 if (offset
>= psize
- VDEV_LABEL_END_SIZE
) {
174 offset
-= psize
- VDEV_LABEL_END_SIZE
;
175 offset
+= (VDEV_LABELS
/ 2) * sizeof (vdev_label_t
);
177 l
= offset
/ sizeof (vdev_label_t
);
178 return (l
< VDEV_LABELS
? l
: -1);
182 vdev_label_read(zio_t
*zio
, vdev_t
*vd
, int l
, abd_t
*buf
, uint64_t offset
,
183 uint64_t size
, zio_done_func_t
*done
, void *private, int flags
)
186 spa_config_held(zio
->io_spa
, SCL_STATE
, RW_READER
) == SCL_STATE
||
187 spa_config_held(zio
->io_spa
, SCL_STATE
, RW_WRITER
) == SCL_STATE
);
188 ASSERT(flags
& ZIO_FLAG_CONFIG_WRITER
);
190 zio_nowait(zio_read_phys(zio
, vd
,
191 vdev_label_offset(vd
->vdev_psize
, l
, offset
),
192 size
, buf
, ZIO_CHECKSUM_LABEL
, done
, private,
193 ZIO_PRIORITY_SYNC_READ
, flags
, B_TRUE
));
197 vdev_label_write(zio_t
*zio
, vdev_t
*vd
, int l
, abd_t
*buf
, uint64_t offset
,
198 uint64_t size
, zio_done_func_t
*done
, void *private, int flags
)
201 spa_config_held(zio
->io_spa
, SCL_STATE
, RW_READER
) == SCL_STATE
||
202 spa_config_held(zio
->io_spa
, SCL_STATE
, RW_WRITER
) == SCL_STATE
);
203 ASSERT(flags
& ZIO_FLAG_CONFIG_WRITER
);
205 zio_nowait(zio_write_phys(zio
, vd
,
206 vdev_label_offset(vd
->vdev_psize
, l
, offset
),
207 size
, buf
, ZIO_CHECKSUM_LABEL
, done
, private,
208 ZIO_PRIORITY_SYNC_WRITE
, flags
, B_TRUE
));
212 * Generate the nvlist representing this vdev's stats
215 vdev_config_generate_stats(vdev_t
*vd
, nvlist_t
*nv
)
221 vs
= kmem_alloc(sizeof (*vs
), KM_SLEEP
);
222 vsx
= kmem_alloc(sizeof (*vsx
), KM_SLEEP
);
224 vdev_get_stats_ex(vd
, vs
, vsx
);
225 fnvlist_add_uint64_array(nv
, ZPOOL_CONFIG_VDEV_STATS
,
226 (uint64_t *)vs
, sizeof (*vs
) / sizeof (uint64_t));
228 kmem_free(vs
, sizeof (*vs
));
231 * Add extended stats into a special extended stats nvlist. This keeps
232 * all the extended stats nicely grouped together. The extended stats
233 * nvlist is then added to the main nvlist.
235 nvx
= fnvlist_alloc();
237 /* ZIOs in flight to disk */
238 fnvlist_add_uint64(nvx
, ZPOOL_CONFIG_VDEV_SYNC_R_ACTIVE_QUEUE
,
239 vsx
->vsx_active_queue
[ZIO_PRIORITY_SYNC_READ
]);
241 fnvlist_add_uint64(nvx
, ZPOOL_CONFIG_VDEV_SYNC_W_ACTIVE_QUEUE
,
242 vsx
->vsx_active_queue
[ZIO_PRIORITY_SYNC_WRITE
]);
244 fnvlist_add_uint64(nvx
, ZPOOL_CONFIG_VDEV_ASYNC_R_ACTIVE_QUEUE
,
245 vsx
->vsx_active_queue
[ZIO_PRIORITY_ASYNC_READ
]);
247 fnvlist_add_uint64(nvx
, ZPOOL_CONFIG_VDEV_ASYNC_W_ACTIVE_QUEUE
,
248 vsx
->vsx_active_queue
[ZIO_PRIORITY_ASYNC_WRITE
]);
250 fnvlist_add_uint64(nvx
, ZPOOL_CONFIG_VDEV_SCRUB_ACTIVE_QUEUE
,
251 vsx
->vsx_active_queue
[ZIO_PRIORITY_SCRUB
]);
254 fnvlist_add_uint64(nvx
, ZPOOL_CONFIG_VDEV_SYNC_R_PEND_QUEUE
,
255 vsx
->vsx_pend_queue
[ZIO_PRIORITY_SYNC_READ
]);
257 fnvlist_add_uint64(nvx
, ZPOOL_CONFIG_VDEV_SYNC_W_PEND_QUEUE
,
258 vsx
->vsx_pend_queue
[ZIO_PRIORITY_SYNC_WRITE
]);
260 fnvlist_add_uint64(nvx
, ZPOOL_CONFIG_VDEV_ASYNC_R_PEND_QUEUE
,
261 vsx
->vsx_pend_queue
[ZIO_PRIORITY_ASYNC_READ
]);
263 fnvlist_add_uint64(nvx
, ZPOOL_CONFIG_VDEV_ASYNC_W_PEND_QUEUE
,
264 vsx
->vsx_pend_queue
[ZIO_PRIORITY_ASYNC_WRITE
]);
266 fnvlist_add_uint64(nvx
, ZPOOL_CONFIG_VDEV_SCRUB_PEND_QUEUE
,
267 vsx
->vsx_pend_queue
[ZIO_PRIORITY_SCRUB
]);
270 fnvlist_add_uint64_array(nvx
, ZPOOL_CONFIG_VDEV_TOT_R_LAT_HISTO
,
271 vsx
->vsx_total_histo
[ZIO_TYPE_READ
],
272 ARRAY_SIZE(vsx
->vsx_total_histo
[ZIO_TYPE_READ
]));
274 fnvlist_add_uint64_array(nvx
, ZPOOL_CONFIG_VDEV_TOT_W_LAT_HISTO
,
275 vsx
->vsx_total_histo
[ZIO_TYPE_WRITE
],
276 ARRAY_SIZE(vsx
->vsx_total_histo
[ZIO_TYPE_WRITE
]));
278 fnvlist_add_uint64_array(nvx
, ZPOOL_CONFIG_VDEV_DISK_R_LAT_HISTO
,
279 vsx
->vsx_disk_histo
[ZIO_TYPE_READ
],
280 ARRAY_SIZE(vsx
->vsx_disk_histo
[ZIO_TYPE_READ
]));
282 fnvlist_add_uint64_array(nvx
, ZPOOL_CONFIG_VDEV_DISK_W_LAT_HISTO
,
283 vsx
->vsx_disk_histo
[ZIO_TYPE_WRITE
],
284 ARRAY_SIZE(vsx
->vsx_disk_histo
[ZIO_TYPE_WRITE
]));
286 fnvlist_add_uint64_array(nvx
, ZPOOL_CONFIG_VDEV_SYNC_R_LAT_HISTO
,
287 vsx
->vsx_queue_histo
[ZIO_PRIORITY_SYNC_READ
],
288 ARRAY_SIZE(vsx
->vsx_queue_histo
[ZIO_PRIORITY_SYNC_READ
]));
290 fnvlist_add_uint64_array(nvx
, ZPOOL_CONFIG_VDEV_SYNC_W_LAT_HISTO
,
291 vsx
->vsx_queue_histo
[ZIO_PRIORITY_SYNC_WRITE
],
292 ARRAY_SIZE(vsx
->vsx_queue_histo
[ZIO_PRIORITY_SYNC_WRITE
]));
294 fnvlist_add_uint64_array(nvx
, ZPOOL_CONFIG_VDEV_ASYNC_R_LAT_HISTO
,
295 vsx
->vsx_queue_histo
[ZIO_PRIORITY_ASYNC_READ
],
296 ARRAY_SIZE(vsx
->vsx_queue_histo
[ZIO_PRIORITY_ASYNC_READ
]));
298 fnvlist_add_uint64_array(nvx
, ZPOOL_CONFIG_VDEV_ASYNC_W_LAT_HISTO
,
299 vsx
->vsx_queue_histo
[ZIO_PRIORITY_ASYNC_WRITE
],
300 ARRAY_SIZE(vsx
->vsx_queue_histo
[ZIO_PRIORITY_ASYNC_WRITE
]));
302 fnvlist_add_uint64_array(nvx
, ZPOOL_CONFIG_VDEV_SCRUB_LAT_HISTO
,
303 vsx
->vsx_queue_histo
[ZIO_PRIORITY_SCRUB
],
304 ARRAY_SIZE(vsx
->vsx_queue_histo
[ZIO_PRIORITY_SCRUB
]));
307 fnvlist_add_uint64_array(nvx
, ZPOOL_CONFIG_VDEV_SYNC_IND_R_HISTO
,
308 vsx
->vsx_ind_histo
[ZIO_PRIORITY_SYNC_READ
],
309 ARRAY_SIZE(vsx
->vsx_ind_histo
[ZIO_PRIORITY_SYNC_READ
]));
311 fnvlist_add_uint64_array(nvx
, ZPOOL_CONFIG_VDEV_SYNC_IND_W_HISTO
,
312 vsx
->vsx_ind_histo
[ZIO_PRIORITY_SYNC_WRITE
],
313 ARRAY_SIZE(vsx
->vsx_ind_histo
[ZIO_PRIORITY_SYNC_WRITE
]));
315 fnvlist_add_uint64_array(nvx
, ZPOOL_CONFIG_VDEV_ASYNC_IND_R_HISTO
,
316 vsx
->vsx_ind_histo
[ZIO_PRIORITY_ASYNC_READ
],
317 ARRAY_SIZE(vsx
->vsx_ind_histo
[ZIO_PRIORITY_ASYNC_READ
]));
319 fnvlist_add_uint64_array(nvx
, ZPOOL_CONFIG_VDEV_ASYNC_IND_W_HISTO
,
320 vsx
->vsx_ind_histo
[ZIO_PRIORITY_ASYNC_WRITE
],
321 ARRAY_SIZE(vsx
->vsx_ind_histo
[ZIO_PRIORITY_ASYNC_WRITE
]));
323 fnvlist_add_uint64_array(nvx
, ZPOOL_CONFIG_VDEV_IND_SCRUB_HISTO
,
324 vsx
->vsx_ind_histo
[ZIO_PRIORITY_SCRUB
],
325 ARRAY_SIZE(vsx
->vsx_ind_histo
[ZIO_PRIORITY_SCRUB
]));
327 fnvlist_add_uint64_array(nvx
, ZPOOL_CONFIG_VDEV_SYNC_AGG_R_HISTO
,
328 vsx
->vsx_agg_histo
[ZIO_PRIORITY_SYNC_READ
],
329 ARRAY_SIZE(vsx
->vsx_agg_histo
[ZIO_PRIORITY_SYNC_READ
]));
331 fnvlist_add_uint64_array(nvx
, ZPOOL_CONFIG_VDEV_SYNC_AGG_W_HISTO
,
332 vsx
->vsx_agg_histo
[ZIO_PRIORITY_SYNC_WRITE
],
333 ARRAY_SIZE(vsx
->vsx_agg_histo
[ZIO_PRIORITY_SYNC_WRITE
]));
335 fnvlist_add_uint64_array(nvx
, ZPOOL_CONFIG_VDEV_ASYNC_AGG_R_HISTO
,
336 vsx
->vsx_agg_histo
[ZIO_PRIORITY_ASYNC_READ
],
337 ARRAY_SIZE(vsx
->vsx_agg_histo
[ZIO_PRIORITY_ASYNC_READ
]));
339 fnvlist_add_uint64_array(nvx
, ZPOOL_CONFIG_VDEV_ASYNC_AGG_W_HISTO
,
340 vsx
->vsx_agg_histo
[ZIO_PRIORITY_ASYNC_WRITE
],
341 ARRAY_SIZE(vsx
->vsx_agg_histo
[ZIO_PRIORITY_ASYNC_WRITE
]));
343 fnvlist_add_uint64_array(nvx
, ZPOOL_CONFIG_VDEV_AGG_SCRUB_HISTO
,
344 vsx
->vsx_agg_histo
[ZIO_PRIORITY_SCRUB
],
345 ARRAY_SIZE(vsx
->vsx_agg_histo
[ZIO_PRIORITY_SCRUB
]));
347 /* Add extended stats nvlist to main nvlist */
348 fnvlist_add_nvlist(nv
, ZPOOL_CONFIG_VDEV_STATS_EX
, nvx
);
351 kmem_free(vsx
, sizeof (*vsx
));
355 * Generate the nvlist representing this vdev's config.
358 vdev_config_generate(spa_t
*spa
, vdev_t
*vd
, boolean_t getstats
,
359 vdev_config_flag_t flags
)
362 nv
= fnvlist_alloc();
364 fnvlist_add_string(nv
, ZPOOL_CONFIG_TYPE
, vd
->vdev_ops
->vdev_op_type
);
365 if (!(flags
& (VDEV_CONFIG_SPARE
| VDEV_CONFIG_L2CACHE
)))
366 fnvlist_add_uint64(nv
, ZPOOL_CONFIG_ID
, vd
->vdev_id
);
367 fnvlist_add_uint64(nv
, ZPOOL_CONFIG_GUID
, vd
->vdev_guid
);
369 if (vd
->vdev_path
!= NULL
)
370 fnvlist_add_string(nv
, ZPOOL_CONFIG_PATH
, vd
->vdev_path
);
372 if (vd
->vdev_devid
!= NULL
)
373 fnvlist_add_string(nv
, ZPOOL_CONFIG_DEVID
, vd
->vdev_devid
);
375 if (vd
->vdev_physpath
!= NULL
)
376 fnvlist_add_string(nv
, ZPOOL_CONFIG_PHYS_PATH
,
379 if (vd
->vdev_enc_sysfs_path
!= NULL
)
380 fnvlist_add_string(nv
, ZPOOL_CONFIG_VDEV_ENC_SYSFS_PATH
,
381 vd
->vdev_enc_sysfs_path
);
383 if (vd
->vdev_fru
!= NULL
)
384 fnvlist_add_string(nv
, ZPOOL_CONFIG_FRU
, vd
->vdev_fru
);
386 if (vd
->vdev_nparity
!= 0) {
387 ASSERT(strcmp(vd
->vdev_ops
->vdev_op_type
,
388 VDEV_TYPE_RAIDZ
) == 0);
391 * Make sure someone hasn't managed to sneak a fancy new vdev
392 * into a crufty old storage pool.
394 ASSERT(vd
->vdev_nparity
== 1 ||
395 (vd
->vdev_nparity
<= 2 &&
396 spa_version(spa
) >= SPA_VERSION_RAIDZ2
) ||
397 (vd
->vdev_nparity
<= 3 &&
398 spa_version(spa
) >= SPA_VERSION_RAIDZ3
));
401 * Note that we'll add the nparity tag even on storage pools
402 * that only support a single parity device -- older software
403 * will just ignore it.
405 fnvlist_add_uint64(nv
, ZPOOL_CONFIG_NPARITY
, vd
->vdev_nparity
);
408 if (vd
->vdev_wholedisk
!= -1ULL)
409 fnvlist_add_uint64(nv
, ZPOOL_CONFIG_WHOLE_DISK
,
412 if (vd
->vdev_not_present
)
413 fnvlist_add_uint64(nv
, ZPOOL_CONFIG_NOT_PRESENT
, 1);
415 if (vd
->vdev_isspare
)
416 fnvlist_add_uint64(nv
, ZPOOL_CONFIG_IS_SPARE
, 1);
418 if (!(flags
& (VDEV_CONFIG_SPARE
| VDEV_CONFIG_L2CACHE
)) &&
419 vd
== vd
->vdev_top
) {
420 fnvlist_add_uint64(nv
, ZPOOL_CONFIG_METASLAB_ARRAY
,
422 fnvlist_add_uint64(nv
, ZPOOL_CONFIG_METASLAB_SHIFT
,
424 fnvlist_add_uint64(nv
, ZPOOL_CONFIG_ASHIFT
, vd
->vdev_ashift
);
425 fnvlist_add_uint64(nv
, ZPOOL_CONFIG_ASIZE
,
427 fnvlist_add_uint64(nv
, ZPOOL_CONFIG_IS_LOG
, vd
->vdev_islog
);
428 if (vd
->vdev_removing
)
429 fnvlist_add_uint64(nv
, ZPOOL_CONFIG_REMOVING
,
433 if (vd
->vdev_dtl_sm
!= NULL
) {
434 fnvlist_add_uint64(nv
, ZPOOL_CONFIG_DTL
,
435 space_map_object(vd
->vdev_dtl_sm
));
439 fnvlist_add_uint64(nv
, ZPOOL_CONFIG_CREATE_TXG
, vd
->vdev_crtxg
);
441 if (flags
& VDEV_CONFIG_MOS
) {
442 if (vd
->vdev_leaf_zap
!= 0) {
443 ASSERT(vd
->vdev_ops
->vdev_op_leaf
);
444 fnvlist_add_uint64(nv
, ZPOOL_CONFIG_VDEV_LEAF_ZAP
,
448 if (vd
->vdev_top_zap
!= 0) {
449 ASSERT(vd
== vd
->vdev_top
);
450 fnvlist_add_uint64(nv
, ZPOOL_CONFIG_VDEV_TOP_ZAP
,
458 vdev_config_generate_stats(vd
, nv
);
460 /* provide either current or previous scan information */
461 if (spa_scan_get_stats(spa
, &ps
) == 0) {
462 fnvlist_add_uint64_array(nv
,
463 ZPOOL_CONFIG_SCAN_STATS
, (uint64_t *)&ps
,
464 sizeof (pool_scan_stat_t
) / sizeof (uint64_t));
468 if (!vd
->vdev_ops
->vdev_op_leaf
) {
472 ASSERT(!vd
->vdev_ishole
);
474 child
= kmem_alloc(vd
->vdev_children
* sizeof (nvlist_t
*),
477 for (c
= 0, idx
= 0; c
< vd
->vdev_children
; c
++) {
478 vdev_t
*cvd
= vd
->vdev_child
[c
];
481 * If we're generating an nvlist of removing
482 * vdevs then skip over any device which is
485 if ((flags
& VDEV_CONFIG_REMOVING
) &&
489 child
[idx
++] = vdev_config_generate(spa
, cvd
,
494 fnvlist_add_nvlist_array(nv
, ZPOOL_CONFIG_CHILDREN
,
498 for (c
= 0; c
< idx
; c
++)
499 nvlist_free(child
[c
]);
501 kmem_free(child
, vd
->vdev_children
* sizeof (nvlist_t
*));
504 const char *aux
= NULL
;
506 if (vd
->vdev_offline
&& !vd
->vdev_tmpoffline
)
507 fnvlist_add_uint64(nv
, ZPOOL_CONFIG_OFFLINE
, B_TRUE
);
508 if (vd
->vdev_resilver_txg
!= 0)
509 fnvlist_add_uint64(nv
, ZPOOL_CONFIG_RESILVER_TXG
,
510 vd
->vdev_resilver_txg
);
511 if (vd
->vdev_faulted
)
512 fnvlist_add_uint64(nv
, ZPOOL_CONFIG_FAULTED
, B_TRUE
);
513 if (vd
->vdev_degraded
)
514 fnvlist_add_uint64(nv
, ZPOOL_CONFIG_DEGRADED
, B_TRUE
);
515 if (vd
->vdev_removed
)
516 fnvlist_add_uint64(nv
, ZPOOL_CONFIG_REMOVED
, B_TRUE
);
517 if (vd
->vdev_unspare
)
518 fnvlist_add_uint64(nv
, ZPOOL_CONFIG_UNSPARE
, B_TRUE
);
520 fnvlist_add_uint64(nv
, ZPOOL_CONFIG_IS_HOLE
, B_TRUE
);
522 /* Set the reason why we're FAULTED/DEGRADED. */
523 switch (vd
->vdev_stat
.vs_aux
) {
524 case VDEV_AUX_ERR_EXCEEDED
:
525 aux
= "err_exceeded";
528 case VDEV_AUX_EXTERNAL
:
533 if (aux
!= NULL
&& !vd
->vdev_tmpoffline
) {
534 fnvlist_add_string(nv
, ZPOOL_CONFIG_AUX_STATE
, aux
);
537 * We're healthy - clear any previous AUX_STATE values.
539 if (nvlist_exists(nv
, ZPOOL_CONFIG_AUX_STATE
))
540 nvlist_remove_all(nv
, ZPOOL_CONFIG_AUX_STATE
);
543 if (vd
->vdev_splitting
&& vd
->vdev_orig_guid
!= 0LL) {
544 fnvlist_add_uint64(nv
, ZPOOL_CONFIG_ORIG_GUID
,
553 * Generate a view of the top-level vdevs. If we currently have holes
554 * in the namespace, then generate an array which contains a list of holey
555 * vdevs. Additionally, add the number of top-level children that currently
559 vdev_top_config_generate(spa_t
*spa
, nvlist_t
*config
)
561 vdev_t
*rvd
= spa
->spa_root_vdev
;
565 array
= kmem_alloc(rvd
->vdev_children
* sizeof (uint64_t), KM_SLEEP
);
567 for (c
= 0, idx
= 0; c
< rvd
->vdev_children
; c
++) {
568 vdev_t
*tvd
= rvd
->vdev_child
[c
];
570 if (tvd
->vdev_ishole
)
575 VERIFY(nvlist_add_uint64_array(config
, ZPOOL_CONFIG_HOLE_ARRAY
,
579 VERIFY(nvlist_add_uint64(config
, ZPOOL_CONFIG_VDEV_CHILDREN
,
580 rvd
->vdev_children
) == 0);
582 kmem_free(array
, rvd
->vdev_children
* sizeof (uint64_t));
586 * Returns the configuration from the label of the given vdev. For vdevs
587 * which don't have a txg value stored on their label (i.e. spares/cache)
588 * or have not been completely initialized (txg = 0) just return
589 * the configuration from the first valid label we find. Otherwise,
590 * find the most up-to-date label that does not exceed the specified
594 vdev_label_read_config(vdev_t
*vd
, uint64_t txg
)
596 spa_t
*spa
= vd
->vdev_spa
;
597 nvlist_t
*config
= NULL
;
601 uint64_t best_txg
= 0;
603 int flags
= ZIO_FLAG_CONFIG_WRITER
| ZIO_FLAG_CANFAIL
|
604 ZIO_FLAG_SPECULATIVE
;
607 ASSERT(spa_config_held(spa
, SCL_STATE_ALL
, RW_WRITER
) == SCL_STATE_ALL
);
609 if (!vdev_readable(vd
))
612 vp_abd
= abd_alloc_linear(sizeof (vdev_phys_t
), B_TRUE
);
613 vp
= abd_to_buf(vp_abd
);
616 for (l
= 0; l
< VDEV_LABELS
; l
++) {
617 nvlist_t
*label
= NULL
;
619 zio
= zio_root(spa
, NULL
, NULL
, flags
);
621 vdev_label_read(zio
, vd
, l
, vp_abd
,
622 offsetof(vdev_label_t
, vl_vdev_phys
),
623 sizeof (vdev_phys_t
), NULL
, NULL
, flags
);
625 if (zio_wait(zio
) == 0 &&
626 nvlist_unpack(vp
->vp_nvlist
, sizeof (vp
->vp_nvlist
),
628 uint64_t label_txg
= 0;
631 * Auxiliary vdevs won't have txg values in their
632 * labels and newly added vdevs may not have been
633 * completely initialized so just return the
634 * configuration from the first valid label we
637 error
= nvlist_lookup_uint64(label
,
638 ZPOOL_CONFIG_POOL_TXG
, &label_txg
);
639 if ((error
|| label_txg
== 0) && !config
) {
642 } else if (label_txg
<= txg
&& label_txg
> best_txg
) {
643 best_txg
= label_txg
;
645 config
= fnvlist_dup(label
);
655 if (config
== NULL
&& !(flags
& ZIO_FLAG_TRYHARD
)) {
656 flags
|= ZIO_FLAG_TRYHARD
;
666 * Determine if a device is in use. The 'spare_guid' parameter will be filled
667 * in with the device guid if this spare is active elsewhere on the system.
670 vdev_inuse(vdev_t
*vd
, uint64_t crtxg
, vdev_labeltype_t reason
,
671 uint64_t *spare_guid
, uint64_t *l2cache_guid
)
673 spa_t
*spa
= vd
->vdev_spa
;
674 uint64_t state
, pool_guid
, device_guid
, txg
, spare_pool
;
681 *l2cache_guid
= 0ULL;
684 * Read the label, if any, and perform some basic sanity checks.
686 if ((label
= vdev_label_read_config(vd
, -1ULL)) == NULL
)
689 (void) nvlist_lookup_uint64(label
, ZPOOL_CONFIG_CREATE_TXG
,
692 if (nvlist_lookup_uint64(label
, ZPOOL_CONFIG_POOL_STATE
,
694 nvlist_lookup_uint64(label
, ZPOOL_CONFIG_GUID
,
695 &device_guid
) != 0) {
700 if (state
!= POOL_STATE_SPARE
&& state
!= POOL_STATE_L2CACHE
&&
701 (nvlist_lookup_uint64(label
, ZPOOL_CONFIG_POOL_GUID
,
703 nvlist_lookup_uint64(label
, ZPOOL_CONFIG_POOL_TXG
,
712 * Check to see if this device indeed belongs to the pool it claims to
713 * be a part of. The only way this is allowed is if the device is a hot
714 * spare (which we check for later on).
716 if (state
!= POOL_STATE_SPARE
&& state
!= POOL_STATE_L2CACHE
&&
717 !spa_guid_exists(pool_guid
, device_guid
) &&
718 !spa_spare_exists(device_guid
, NULL
, NULL
) &&
719 !spa_l2cache_exists(device_guid
, NULL
))
723 * If the transaction group is zero, then this an initialized (but
724 * unused) label. This is only an error if the create transaction
725 * on-disk is the same as the one we're using now, in which case the
726 * user has attempted to add the same vdev multiple times in the same
729 if (state
!= POOL_STATE_SPARE
&& state
!= POOL_STATE_L2CACHE
&&
730 txg
== 0 && vdtxg
== crtxg
)
734 * Check to see if this is a spare device. We do an explicit check for
735 * spa_has_spare() here because it may be on our pending list of spares
736 * to add. We also check if it is an l2cache device.
738 if (spa_spare_exists(device_guid
, &spare_pool
, NULL
) ||
739 spa_has_spare(spa
, device_guid
)) {
741 *spare_guid
= device_guid
;
744 case VDEV_LABEL_CREATE
:
745 case VDEV_LABEL_L2CACHE
:
748 case VDEV_LABEL_REPLACE
:
749 return (!spa_has_spare(spa
, device_guid
) ||
752 case VDEV_LABEL_SPARE
:
753 return (spa_has_spare(spa
, device_guid
));
760 * Check to see if this is an l2cache device.
762 if (spa_l2cache_exists(device_guid
, NULL
))
766 * We can't rely on a pool's state if it's been imported
767 * read-only. Instead we look to see if the pools is marked
768 * read-only in the namespace and set the state to active.
770 if (state
!= POOL_STATE_SPARE
&& state
!= POOL_STATE_L2CACHE
&&
771 (spa
= spa_by_guid(pool_guid
, device_guid
)) != NULL
&&
772 spa_mode(spa
) == FREAD
)
773 state
= POOL_STATE_ACTIVE
;
776 * If the device is marked ACTIVE, then this device is in use by another
777 * pool on the system.
779 return (state
== POOL_STATE_ACTIVE
);
783 * Initialize a vdev label. We check to make sure each leaf device is not in
784 * use, and writable. We put down an initial label which we will later
785 * overwrite with a complete label. Note that it's important to do this
786 * sequentially, not in parallel, so that we catch cases of multiple use of the
787 * same leaf vdev in the vdev we're creating -- e.g. mirroring a disk with
791 vdev_label_init(vdev_t
*vd
, uint64_t crtxg
, vdev_labeltype_t reason
)
793 spa_t
*spa
= vd
->vdev_spa
;
804 uint64_t spare_guid
= 0, l2cache_guid
= 0;
805 int flags
= ZIO_FLAG_CONFIG_WRITER
| ZIO_FLAG_CANFAIL
;
809 ASSERT(spa_config_held(spa
, SCL_ALL
, RW_WRITER
) == SCL_ALL
);
811 for (c
= 0; c
< vd
->vdev_children
; c
++)
812 if ((error
= vdev_label_init(vd
->vdev_child
[c
],
813 crtxg
, reason
)) != 0)
816 /* Track the creation time for this vdev */
817 vd
->vdev_crtxg
= crtxg
;
819 if (!vd
->vdev_ops
->vdev_op_leaf
|| !spa_writeable(spa
))
823 * Dead vdevs cannot be initialized.
825 if (vdev_is_dead(vd
))
826 return (SET_ERROR(EIO
));
829 * Determine if the vdev is in use.
831 if (reason
!= VDEV_LABEL_REMOVE
&& reason
!= VDEV_LABEL_SPLIT
&&
832 vdev_inuse(vd
, crtxg
, reason
, &spare_guid
, &l2cache_guid
))
833 return (SET_ERROR(EBUSY
));
836 * If this is a request to add or replace a spare or l2cache device
837 * that is in use elsewhere on the system, then we must update the
838 * guid (which was initialized to a random value) to reflect the
839 * actual GUID (which is shared between multiple pools).
841 if (reason
!= VDEV_LABEL_REMOVE
&& reason
!= VDEV_LABEL_L2CACHE
&&
842 spare_guid
!= 0ULL) {
843 uint64_t guid_delta
= spare_guid
- vd
->vdev_guid
;
845 vd
->vdev_guid
+= guid_delta
;
847 for (pvd
= vd
; pvd
!= NULL
; pvd
= pvd
->vdev_parent
)
848 pvd
->vdev_guid_sum
+= guid_delta
;
851 * If this is a replacement, then we want to fallthrough to the
852 * rest of the code. If we're adding a spare, then it's already
853 * labeled appropriately and we can just return.
855 if (reason
== VDEV_LABEL_SPARE
)
857 ASSERT(reason
== VDEV_LABEL_REPLACE
||
858 reason
== VDEV_LABEL_SPLIT
);
861 if (reason
!= VDEV_LABEL_REMOVE
&& reason
!= VDEV_LABEL_SPARE
&&
862 l2cache_guid
!= 0ULL) {
863 uint64_t guid_delta
= l2cache_guid
- vd
->vdev_guid
;
865 vd
->vdev_guid
+= guid_delta
;
867 for (pvd
= vd
; pvd
!= NULL
; pvd
= pvd
->vdev_parent
)
868 pvd
->vdev_guid_sum
+= guid_delta
;
871 * If this is a replacement, then we want to fallthrough to the
872 * rest of the code. If we're adding an l2cache, then it's
873 * already labeled appropriately and we can just return.
875 if (reason
== VDEV_LABEL_L2CACHE
)
877 ASSERT(reason
== VDEV_LABEL_REPLACE
);
881 * Initialize its label.
883 vp_abd
= abd_alloc_linear(sizeof (vdev_phys_t
), B_TRUE
);
884 abd_zero(vp_abd
, sizeof (vdev_phys_t
));
885 vp
= abd_to_buf(vp_abd
);
888 * Generate a label describing the pool and our top-level vdev.
889 * We mark it as being from txg 0 to indicate that it's not
890 * really part of an active pool just yet. The labels will
891 * be written again with a meaningful txg by spa_sync().
893 if (reason
== VDEV_LABEL_SPARE
||
894 (reason
== VDEV_LABEL_REMOVE
&& vd
->vdev_isspare
)) {
896 * For inactive hot spares, we generate a special label that
897 * identifies as a mutually shared hot spare. We write the
898 * label if we are adding a hot spare, or if we are removing an
899 * active hot spare (in which case we want to revert the
902 VERIFY(nvlist_alloc(&label
, NV_UNIQUE_NAME
, KM_SLEEP
) == 0);
904 VERIFY(nvlist_add_uint64(label
, ZPOOL_CONFIG_VERSION
,
905 spa_version(spa
)) == 0);
906 VERIFY(nvlist_add_uint64(label
, ZPOOL_CONFIG_POOL_STATE
,
907 POOL_STATE_SPARE
) == 0);
908 VERIFY(nvlist_add_uint64(label
, ZPOOL_CONFIG_GUID
,
909 vd
->vdev_guid
) == 0);
910 } else if (reason
== VDEV_LABEL_L2CACHE
||
911 (reason
== VDEV_LABEL_REMOVE
&& vd
->vdev_isl2cache
)) {
913 * For level 2 ARC devices, add a special label.
915 VERIFY(nvlist_alloc(&label
, NV_UNIQUE_NAME
, KM_SLEEP
) == 0);
917 VERIFY(nvlist_add_uint64(label
, ZPOOL_CONFIG_VERSION
,
918 spa_version(spa
)) == 0);
919 VERIFY(nvlist_add_uint64(label
, ZPOOL_CONFIG_POOL_STATE
,
920 POOL_STATE_L2CACHE
) == 0);
921 VERIFY(nvlist_add_uint64(label
, ZPOOL_CONFIG_GUID
,
922 vd
->vdev_guid
) == 0);
926 if (reason
== VDEV_LABEL_SPLIT
)
927 txg
= spa
->spa_uberblock
.ub_txg
;
928 label
= spa_config_generate(spa
, vd
, txg
, B_FALSE
);
931 * Add our creation time. This allows us to detect multiple
932 * vdev uses as described above, and automatically expires if we
935 VERIFY(nvlist_add_uint64(label
, ZPOOL_CONFIG_CREATE_TXG
,
940 buflen
= sizeof (vp
->vp_nvlist
);
942 error
= nvlist_pack(label
, &buf
, &buflen
, NV_ENCODE_XDR
, KM_SLEEP
);
946 /* EFAULT means nvlist_pack ran out of room */
947 return (error
== EFAULT
? ENAMETOOLONG
: EINVAL
);
951 * Initialize uberblock template.
953 ub_abd
= abd_alloc_linear(VDEV_UBERBLOCK_RING
, B_TRUE
);
954 abd_zero(ub_abd
, VDEV_UBERBLOCK_RING
);
955 abd_copy_from_buf(ub_abd
, &spa
->spa_uberblock
, sizeof (uberblock_t
));
956 ub
= abd_to_buf(ub_abd
);
959 /* Initialize the 2nd padding area. */
960 pad2
= abd_alloc_for_io(VDEV_PAD_SIZE
, B_TRUE
);
961 abd_zero(pad2
, VDEV_PAD_SIZE
);
964 * Write everything in parallel.
967 zio
= zio_root(spa
, NULL
, NULL
, flags
);
969 for (l
= 0; l
< VDEV_LABELS
; l
++) {
971 vdev_label_write(zio
, vd
, l
, vp_abd
,
972 offsetof(vdev_label_t
, vl_vdev_phys
),
973 sizeof (vdev_phys_t
), NULL
, NULL
, flags
);
976 * Skip the 1st padding area.
977 * Zero out the 2nd padding area where it might have
978 * left over data from previous filesystem format.
980 vdev_label_write(zio
, vd
, l
, pad2
,
981 offsetof(vdev_label_t
, vl_pad2
),
982 VDEV_PAD_SIZE
, NULL
, NULL
, flags
);
984 vdev_label_write(zio
, vd
, l
, ub_abd
,
985 offsetof(vdev_label_t
, vl_uberblock
),
986 VDEV_UBERBLOCK_RING
, NULL
, NULL
, flags
);
989 error
= zio_wait(zio
);
991 if (error
!= 0 && !(flags
& ZIO_FLAG_TRYHARD
)) {
992 flags
|= ZIO_FLAG_TRYHARD
;
1002 * If this vdev hasn't been previously identified as a spare, then we
1003 * mark it as such only if a) we are labeling it as a spare, or b) it
1004 * exists as a spare elsewhere in the system. Do the same for
1005 * level 2 ARC devices.
1007 if (error
== 0 && !vd
->vdev_isspare
&&
1008 (reason
== VDEV_LABEL_SPARE
||
1009 spa_spare_exists(vd
->vdev_guid
, NULL
, NULL
)))
1012 if (error
== 0 && !vd
->vdev_isl2cache
&&
1013 (reason
== VDEV_LABEL_L2CACHE
||
1014 spa_l2cache_exists(vd
->vdev_guid
, NULL
)))
1015 spa_l2cache_add(vd
);
1021 * ==========================================================================
1022 * uberblock load/sync
1023 * ==========================================================================
1027 * Consider the following situation: txg is safely synced to disk. We've
1028 * written the first uberblock for txg + 1, and then we lose power. When we
1029 * come back up, we fail to see the uberblock for txg + 1 because, say,
1030 * it was on a mirrored device and the replica to which we wrote txg + 1
1031 * is now offline. If we then make some changes and sync txg + 1, and then
1032 * the missing replica comes back, then for a few seconds we'll have two
1033 * conflicting uberblocks on disk with the same txg. The solution is simple:
1034 * among uberblocks with equal txg, choose the one with the latest timestamp.
1037 vdev_uberblock_compare(const uberblock_t
*ub1
, const uberblock_t
*ub2
)
1039 int cmp
= AVL_CMP(ub1
->ub_txg
, ub2
->ub_txg
);
1043 return (AVL_CMP(ub1
->ub_timestamp
, ub2
->ub_timestamp
));
1047 uberblock_t
*ubl_ubbest
; /* Best uberblock */
1048 vdev_t
*ubl_vd
; /* vdev associated with the above */
1052 vdev_uberblock_load_done(zio_t
*zio
)
1054 vdev_t
*vd
= zio
->io_vd
;
1055 spa_t
*spa
= zio
->io_spa
;
1056 zio_t
*rio
= zio
->io_private
;
1057 uberblock_t
*ub
= abd_to_buf(zio
->io_abd
);
1058 struct ubl_cbdata
*cbp
= rio
->io_private
;
1060 ASSERT3U(zio
->io_size
, ==, VDEV_UBERBLOCK_SIZE(vd
));
1062 if (zio
->io_error
== 0 && uberblock_verify(ub
) == 0) {
1063 mutex_enter(&rio
->io_lock
);
1064 if (ub
->ub_txg
<= spa
->spa_load_max_txg
&&
1065 vdev_uberblock_compare(ub
, cbp
->ubl_ubbest
) > 0) {
1067 * Keep track of the vdev in which this uberblock
1068 * was found. We will use this information later
1069 * to obtain the config nvlist associated with
1072 *cbp
->ubl_ubbest
= *ub
;
1075 mutex_exit(&rio
->io_lock
);
1078 abd_free(zio
->io_abd
);
1082 vdev_uberblock_load_impl(zio_t
*zio
, vdev_t
*vd
, int flags
,
1083 struct ubl_cbdata
*cbp
)
1085 for (int c
= 0; c
< vd
->vdev_children
; c
++)
1086 vdev_uberblock_load_impl(zio
, vd
->vdev_child
[c
], flags
, cbp
);
1088 if (vd
->vdev_ops
->vdev_op_leaf
&& vdev_readable(vd
)) {
1089 for (int l
= 0; l
< VDEV_LABELS
; l
++) {
1090 for (int n
= 0; n
< VDEV_UBERBLOCK_COUNT(vd
); n
++) {
1091 vdev_label_read(zio
, vd
, l
,
1092 abd_alloc_linear(VDEV_UBERBLOCK_SIZE(vd
),
1093 B_TRUE
), VDEV_UBERBLOCK_OFFSET(vd
, n
),
1094 VDEV_UBERBLOCK_SIZE(vd
),
1095 vdev_uberblock_load_done
, zio
, flags
);
1102 * Reads the 'best' uberblock from disk along with its associated
1103 * configuration. First, we read the uberblock array of each label of each
1104 * vdev, keeping track of the uberblock with the highest txg in each array.
1105 * Then, we read the configuration from the same vdev as the best uberblock.
1108 vdev_uberblock_load(vdev_t
*rvd
, uberblock_t
*ub
, nvlist_t
**config
)
1111 spa_t
*spa
= rvd
->vdev_spa
;
1112 struct ubl_cbdata cb
;
1113 int flags
= ZIO_FLAG_CONFIG_WRITER
| ZIO_FLAG_CANFAIL
|
1114 ZIO_FLAG_SPECULATIVE
| ZIO_FLAG_TRYHARD
;
1119 bzero(ub
, sizeof (uberblock_t
));
1125 spa_config_enter(spa
, SCL_ALL
, FTAG
, RW_WRITER
);
1126 zio
= zio_root(spa
, NULL
, &cb
, flags
);
1127 vdev_uberblock_load_impl(zio
, rvd
, flags
, &cb
);
1128 (void) zio_wait(zio
);
1131 * It's possible that the best uberblock was discovered on a label
1132 * that has a configuration which was written in a future txg.
1133 * Search all labels on this vdev to find the configuration that
1134 * matches the txg for our uberblock.
1136 if (cb
.ubl_vd
!= NULL
)
1137 *config
= vdev_label_read_config(cb
.ubl_vd
, ub
->ub_txg
);
1138 spa_config_exit(spa
, SCL_ALL
, FTAG
);
1142 * For use when a leaf vdev is expanded.
1143 * The location of labels 2 and 3 changed, and at the new location the
1144 * uberblock rings are either empty or contain garbage. The sync will write
1145 * new configs there because the vdev is dirty, but expansion also needs the
1146 * uberblock rings copied. Read them from label 0 which did not move.
1148 * Since the point is to populate labels {2,3} with valid uberblocks,
1149 * we zero uberblocks we fail to read or which are not valid.
1153 vdev_copy_uberblocks(vdev_t
*vd
)
1157 int locks
= (SCL_L2ARC
| SCL_ZIO
);
1158 int flags
= ZIO_FLAG_CONFIG_WRITER
| ZIO_FLAG_CANFAIL
|
1159 ZIO_FLAG_SPECULATIVE
;
1161 ASSERT(spa_config_held(vd
->vdev_spa
, SCL_STATE
, RW_READER
) ==
1163 ASSERT(vd
->vdev_ops
->vdev_op_leaf
);
1165 spa_config_enter(vd
->vdev_spa
, locks
, FTAG
, RW_READER
);
1167 ub_abd
= abd_alloc_linear(VDEV_UBERBLOCK_SIZE(vd
), B_TRUE
);
1169 write_zio
= zio_root(vd
->vdev_spa
, NULL
, NULL
, flags
);
1170 for (int n
= 0; n
< VDEV_UBERBLOCK_COUNT(vd
); n
++) {
1171 const int src_label
= 0;
1174 zio
= zio_root(vd
->vdev_spa
, NULL
, NULL
, flags
);
1175 vdev_label_read(zio
, vd
, src_label
, ub_abd
,
1176 VDEV_UBERBLOCK_OFFSET(vd
, n
), VDEV_UBERBLOCK_SIZE(vd
),
1179 if (zio_wait(zio
) || uberblock_verify(abd_to_buf(ub_abd
)))
1180 abd_zero(ub_abd
, VDEV_UBERBLOCK_SIZE(vd
));
1182 for (int l
= 2; l
< VDEV_LABELS
; l
++)
1183 vdev_label_write(write_zio
, vd
, l
, ub_abd
,
1184 VDEV_UBERBLOCK_OFFSET(vd
, n
),
1185 VDEV_UBERBLOCK_SIZE(vd
), NULL
, NULL
,
1186 flags
| ZIO_FLAG_DONT_PROPAGATE
);
1188 (void) zio_wait(write_zio
);
1190 spa_config_exit(vd
->vdev_spa
, locks
, FTAG
);
1196 * On success, increment root zio's count of good writes.
1197 * We only get credit for writes to known-visible vdevs; see spa_vdev_add().
1200 vdev_uberblock_sync_done(zio_t
*zio
)
1202 uint64_t *good_writes
= zio
->io_private
;
1204 if (zio
->io_error
== 0 && zio
->io_vd
->vdev_top
->vdev_ms_array
!= 0)
1205 atomic_inc_64(good_writes
);
1209 * Write the uberblock to all labels of all leaves of the specified vdev.
1212 vdev_uberblock_sync(zio_t
*zio
, uberblock_t
*ub
, vdev_t
*vd
, int flags
)
1214 for (int c
= 0; c
< vd
->vdev_children
; c
++)
1215 vdev_uberblock_sync(zio
, ub
, vd
->vdev_child
[c
], flags
);
1217 if (!vd
->vdev_ops
->vdev_op_leaf
)
1220 if (!vdev_writeable(vd
))
1223 /* If the vdev was expanded, need to copy uberblock rings. */
1224 if (vd
->vdev_state
== VDEV_STATE_HEALTHY
&&
1225 vd
->vdev_copy_uberblocks
== B_TRUE
) {
1226 vdev_copy_uberblocks(vd
);
1227 vd
->vdev_copy_uberblocks
= B_FALSE
;
1230 int m
= spa_multihost(vd
->vdev_spa
) ? MMP_BLOCKS_PER_LABEL
: 0;
1231 int n
= ub
->ub_txg
% (VDEV_UBERBLOCK_COUNT(vd
) - m
);
1233 /* Copy the uberblock_t into the ABD */
1234 abd_t
*ub_abd
= abd_alloc_for_io(VDEV_UBERBLOCK_SIZE(vd
), B_TRUE
);
1235 abd_zero(ub_abd
, VDEV_UBERBLOCK_SIZE(vd
));
1236 abd_copy_from_buf(ub_abd
, ub
, sizeof (uberblock_t
));
1238 for (int l
= 0; l
< VDEV_LABELS
; l
++)
1239 vdev_label_write(zio
, vd
, l
, ub_abd
,
1240 VDEV_UBERBLOCK_OFFSET(vd
, n
), VDEV_UBERBLOCK_SIZE(vd
),
1241 vdev_uberblock_sync_done
, zio
->io_private
,
1242 flags
| ZIO_FLAG_DONT_PROPAGATE
);
1247 /* Sync the uberblocks to all vdevs in svd[] */
1249 vdev_uberblock_sync_list(vdev_t
**svd
, int svdcount
, uberblock_t
*ub
, int flags
)
1251 spa_t
*spa
= svd
[0]->vdev_spa
;
1253 uint64_t good_writes
= 0;
1256 zio
= zio_root(spa
, NULL
, &good_writes
, flags
);
1258 for (v
= 0; v
< svdcount
; v
++)
1259 vdev_uberblock_sync(zio
, ub
, svd
[v
], flags
);
1261 (void) zio_wait(zio
);
1264 * Flush the uberblocks to disk. This ensures that the odd labels
1265 * are no longer needed (because the new uberblocks and the even
1266 * labels are safely on disk), so it is safe to overwrite them.
1268 zio
= zio_root(spa
, NULL
, NULL
, flags
);
1270 for (v
= 0; v
< svdcount
; v
++)
1271 zio_flush(zio
, svd
[v
]);
1273 (void) zio_wait(zio
);
1275 return (good_writes
>= 1 ? 0 : EIO
);
1279 * On success, increment the count of good writes for our top-level vdev.
1282 vdev_label_sync_done(zio_t
*zio
)
1284 uint64_t *good_writes
= zio
->io_private
;
1286 if (zio
->io_error
== 0)
1287 atomic_inc_64(good_writes
);
1291 * If there weren't enough good writes, indicate failure to the parent.
1294 vdev_label_sync_top_done(zio_t
*zio
)
1296 uint64_t *good_writes
= zio
->io_private
;
1298 if (*good_writes
== 0)
1299 zio
->io_error
= SET_ERROR(EIO
);
1301 kmem_free(good_writes
, sizeof (uint64_t));
1305 * We ignore errors for log and cache devices, simply free the private data.
1308 vdev_label_sync_ignore_done(zio_t
*zio
)
1310 kmem_free(zio
->io_private
, sizeof (uint64_t));
1314 * Write all even or odd labels to all leaves of the specified vdev.
1317 vdev_label_sync(zio_t
*zio
, vdev_t
*vd
, int l
, uint64_t txg
, int flags
)
1326 for (c
= 0; c
< vd
->vdev_children
; c
++)
1327 vdev_label_sync(zio
, vd
->vdev_child
[c
], l
, txg
, flags
);
1329 if (!vd
->vdev_ops
->vdev_op_leaf
)
1332 if (!vdev_writeable(vd
))
1336 * Generate a label describing the top-level config to which we belong.
1338 label
= spa_config_generate(vd
->vdev_spa
, vd
, txg
, B_FALSE
);
1340 vp_abd
= abd_alloc_linear(sizeof (vdev_phys_t
), B_TRUE
);
1341 abd_zero(vp_abd
, sizeof (vdev_phys_t
));
1342 vp
= abd_to_buf(vp_abd
);
1344 buf
= vp
->vp_nvlist
;
1345 buflen
= sizeof (vp
->vp_nvlist
);
1347 if (!nvlist_pack(label
, &buf
, &buflen
, NV_ENCODE_XDR
, KM_SLEEP
)) {
1348 for (; l
< VDEV_LABELS
; l
+= 2) {
1349 vdev_label_write(zio
, vd
, l
, vp_abd
,
1350 offsetof(vdev_label_t
, vl_vdev_phys
),
1351 sizeof (vdev_phys_t
),
1352 vdev_label_sync_done
, zio
->io_private
,
1353 flags
| ZIO_FLAG_DONT_PROPAGATE
);
1362 vdev_label_sync_list(spa_t
*spa
, int l
, uint64_t txg
, int flags
)
1364 list_t
*dl
= &spa
->spa_config_dirty_list
;
1370 * Write the new labels to disk.
1372 zio
= zio_root(spa
, NULL
, NULL
, flags
);
1374 for (vd
= list_head(dl
); vd
!= NULL
; vd
= list_next(dl
, vd
)) {
1375 uint64_t *good_writes
;
1378 ASSERT(!vd
->vdev_ishole
);
1380 good_writes
= kmem_zalloc(sizeof (uint64_t), KM_SLEEP
);
1381 vio
= zio_null(zio
, spa
, NULL
,
1382 (vd
->vdev_islog
|| vd
->vdev_aux
!= NULL
) ?
1383 vdev_label_sync_ignore_done
: vdev_label_sync_top_done
,
1384 good_writes
, flags
);
1385 vdev_label_sync(vio
, vd
, l
, txg
, flags
);
1389 error
= zio_wait(zio
);
1392 * Flush the new labels to disk.
1394 zio
= zio_root(spa
, NULL
, NULL
, flags
);
1396 for (vd
= list_head(dl
); vd
!= NULL
; vd
= list_next(dl
, vd
))
1399 (void) zio_wait(zio
);
1405 * Sync the uberblock and any changes to the vdev configuration.
1407 * The order of operations is carefully crafted to ensure that
1408 * if the system panics or loses power at any time, the state on disk
1409 * is still transactionally consistent. The in-line comments below
1410 * describe the failure semantics at each stage.
1412 * Moreover, vdev_config_sync() is designed to be idempotent: if it fails
1413 * at any time, you can just call it again, and it will resume its work.
1416 vdev_config_sync(vdev_t
**svd
, int svdcount
, uint64_t txg
)
1418 spa_t
*spa
= svd
[0]->vdev_spa
;
1419 uberblock_t
*ub
= &spa
->spa_uberblock
;
1423 int flags
= ZIO_FLAG_CONFIG_WRITER
| ZIO_FLAG_CANFAIL
;
1427 * Normally, we don't want to try too hard to write every label and
1428 * uberblock. If there is a flaky disk, we don't want the rest of the
1429 * sync process to block while we retry. But if we can't write a
1430 * single label out, we should retry with ZIO_FLAG_TRYHARD before
1431 * bailing out and declaring the pool faulted.
1434 if ((flags
& ZIO_FLAG_TRYHARD
) != 0)
1436 flags
|= ZIO_FLAG_TRYHARD
;
1439 ASSERT(ub
->ub_txg
<= txg
);
1442 * If this isn't a resync due to I/O errors,
1443 * and nothing changed in this transaction group,
1444 * and the vdev configuration hasn't changed,
1445 * then there's nothing to do.
1447 if (ub
->ub_txg
< txg
) {
1448 boolean_t changed
= uberblock_update(ub
, spa
->spa_root_vdev
,
1449 txg
, spa
->spa_mmp
.mmp_delay
);
1451 if (!changed
&& list_is_empty(&spa
->spa_config_dirty_list
))
1455 if (txg
> spa_freeze_txg(spa
))
1458 ASSERT(txg
<= spa
->spa_final_txg
);
1461 * Flush the write cache of every disk that's been written to
1462 * in this transaction group. This ensures that all blocks
1463 * written in this txg will be committed to stable storage
1464 * before any uberblock that references them.
1466 zio
= zio_root(spa
, NULL
, NULL
, flags
);
1468 for (vd
= txg_list_head(&spa
->spa_vdev_txg_list
, TXG_CLEAN(txg
)); vd
;
1469 vd
= txg_list_next(&spa
->spa_vdev_txg_list
, vd
, TXG_CLEAN(txg
)))
1472 (void) zio_wait(zio
);
1475 * Sync out the even labels (L0, L2) for every dirty vdev. If the
1476 * system dies in the middle of this process, that's OK: all of the
1477 * even labels that made it to disk will be newer than any uberblock,
1478 * and will therefore be considered invalid. The odd labels (L1, L3),
1479 * which have not yet been touched, will still be valid. We flush
1480 * the new labels to disk to ensure that all even-label updates
1481 * are committed to stable storage before the uberblock update.
1483 if ((error
= vdev_label_sync_list(spa
, 0, txg
, flags
)) != 0)
1487 * Sync the uberblocks to all vdevs in svd[].
1488 * If the system dies in the middle of this step, there are two cases
1489 * to consider, and the on-disk state is consistent either way:
1491 * (1) If none of the new uberblocks made it to disk, then the
1492 * previous uberblock will be the newest, and the odd labels
1493 * (which had not yet been touched) will be valid with respect
1494 * to that uberblock.
1496 * (2) If one or more new uberblocks made it to disk, then they
1497 * will be the newest, and the even labels (which had all
1498 * been successfully committed) will be valid with respect
1499 * to the new uberblocks.
1501 if ((error
= vdev_uberblock_sync_list(svd
, svdcount
, ub
, flags
)) != 0)
1504 if (spa_multihost(spa
))
1505 mmp_update_uberblock(spa
, ub
);
1508 * Sync out odd labels for every dirty vdev. If the system dies
1509 * in the middle of this process, the even labels and the new
1510 * uberblocks will suffice to open the pool. The next time
1511 * the pool is opened, the first thing we'll do -- before any
1512 * user data is modified -- is mark every vdev dirty so that
1513 * all labels will be brought up to date. We flush the new labels
1514 * to disk to ensure that all odd-label updates are committed to
1515 * stable storage before the next transaction group begins.
1517 if ((error
= vdev_label_sync_list(spa
, 1, txg
, flags
)) != 0)