]>
Commit | Line | Data |
---|---|---|
34dc7c2f BB |
1 | /* |
2 | * CDDL HEADER START | |
3 | * | |
4 | * The contents of this file are subject to the terms of the | |
5 | * Common Development and Distribution License (the "License"). | |
6 | * You may not use this file except in compliance with the License. | |
7 | * | |
8 | * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE | |
9 | * or http://www.opensolaris.org/os/licensing. | |
10 | * See the License for the specific language governing permissions | |
11 | * and limitations under the License. | |
12 | * | |
13 | * When distributing Covered Code, include this CDDL HEADER in each | |
14 | * file and include the License file at usr/src/OPENSOLARIS.LICENSE. | |
15 | * If applicable, add the following below this CDDL HEADER, with the | |
16 | * fields enclosed by brackets "[]" replaced with your own identifying | |
17 | * information: Portions Copyright [yyyy] [name of copyright owner] | |
18 | * | |
19 | * CDDL HEADER END | |
20 | */ | |
21 | /* | |
428870ff | 22 | * Copyright (c) 2006, 2010, Oracle and/or its affiliates. All rights reserved. |
ea04106b | 23 | * Copyright (c) 2013, 2014 by Delphix. All rights reserved. |
34dc7c2f BB |
24 | */ |
25 | ||
34dc7c2f BB |
26 | /* |
27 | * Routines to manage the on-disk persistent error log. | |
28 | * | |
29 | * Each pool stores a log of all logical data errors seen during normal | |
30 | * operation. This is actually the union of two distinct logs: the last log, | |
31 | * and the current log. All errors seen are logged to the current log. When a | |
32 | * scrub completes, the current log becomes the last log, the last log is thrown | |
33 | * out, and the current log is reinitialized. This way, if an error is somehow | |
34 | * corrected, a new scrub will show that that it no longer exists, and will be | |
35 | * deleted from the log when the scrub completes. | |
36 | * | |
37 | * The log is stored using a ZAP object whose key is a string form of the | |
ea04106b | 38 | * zbookmark_phys tuple (objset, object, level, blkid), and whose contents is an |
34dc7c2f BB |
39 | * optional 'objset:object' human-readable string describing the data. When an |
40 | * error is first logged, this string will be empty, indicating that no name is | |
41 | * known. This prevents us from having to issue a potentially large amount of | |
42 | * I/O to discover the object name during an error path. Instead, we do the | |
43 | * calculation when the data is requested, storing the result so future queries | |
44 | * will be faster. | |
45 | * | |
46 | * This log is then shipped into an nvlist where the key is the dataset name and | |
47 | * the value is the object name. Userland is then responsible for uniquifying | |
48 | * this list and displaying it to the user. | |
49 | */ | |
50 | ||
51 | #include <sys/dmu_tx.h> | |
52 | #include <sys/spa.h> | |
53 | #include <sys/spa_impl.h> | |
54 | #include <sys/zap.h> | |
55 | #include <sys/zio.h> | |
56 | ||
34dc7c2f BB |
57 | |
58 | /* | |
59 | * Convert a bookmark to a string. | |
60 | */ | |
61 | static void | |
ea04106b | 62 | bookmark_to_name(zbookmark_phys_t *zb, char *buf, size_t len) |
34dc7c2f BB |
63 | { |
64 | (void) snprintf(buf, len, "%llx:%llx:%llx:%llx", | |
65 | (u_longlong_t)zb->zb_objset, (u_longlong_t)zb->zb_object, | |
66 | (u_longlong_t)zb->zb_level, (u_longlong_t)zb->zb_blkid); | |
67 | } | |
68 | ||
69 | /* | |
70 | * Convert a string to a bookmark | |
71 | */ | |
72 | #ifdef _KERNEL | |
73 | static void | |
ea04106b | 74 | name_to_bookmark(char *buf, zbookmark_phys_t *zb) |
34dc7c2f | 75 | { |
cae5b340 | 76 | zb->zb_objset = zfs_strtonum(buf, &buf); |
34dc7c2f | 77 | ASSERT(*buf == ':'); |
cae5b340 | 78 | zb->zb_object = zfs_strtonum(buf + 1, &buf); |
34dc7c2f | 79 | ASSERT(*buf == ':'); |
cae5b340 | 80 | zb->zb_level = (int)zfs_strtonum(buf + 1, &buf); |
34dc7c2f | 81 | ASSERT(*buf == ':'); |
cae5b340 | 82 | zb->zb_blkid = zfs_strtonum(buf + 1, &buf); |
34dc7c2f BB |
83 | ASSERT(*buf == '\0'); |
84 | } | |
85 | #endif | |
86 | ||
87 | /* | |
88 | * Log an uncorrectable error to the persistent error log. We add it to the | |
89 | * spa's list of pending errors. The changes are actually synced out to disk | |
90 | * during spa_errlog_sync(). | |
91 | */ | |
92 | void | |
93 | spa_log_error(spa_t *spa, zio_t *zio) | |
94 | { | |
ea04106b | 95 | zbookmark_phys_t *zb = &zio->io_logical->io_bookmark; |
34dc7c2f BB |
96 | spa_error_entry_t search; |
97 | spa_error_entry_t *new; | |
98 | avl_tree_t *tree; | |
99 | avl_index_t where; | |
100 | ||
101 | /* | |
102 | * If we are trying to import a pool, ignore any errors, as we won't be | |
103 | * writing to the pool any time soon. | |
104 | */ | |
428870ff | 105 | if (spa_load_state(spa) == SPA_LOAD_TRYIMPORT) |
34dc7c2f BB |
106 | return; |
107 | ||
108 | mutex_enter(&spa->spa_errlist_lock); | |
109 | ||
110 | /* | |
111 | * If we have had a request to rotate the log, log it to the next list | |
112 | * instead of the current one. | |
113 | */ | |
114 | if (spa->spa_scrub_active || spa->spa_scrub_finished) | |
115 | tree = &spa->spa_errlist_scrub; | |
116 | else | |
117 | tree = &spa->spa_errlist_last; | |
118 | ||
119 | search.se_bookmark = *zb; | |
120 | if (avl_find(tree, &search, &where) != NULL) { | |
121 | mutex_exit(&spa->spa_errlist_lock); | |
122 | return; | |
123 | } | |
124 | ||
125 | new = kmem_zalloc(sizeof (spa_error_entry_t), KM_SLEEP); | |
126 | new->se_bookmark = *zb; | |
127 | avl_insert(tree, new, where); | |
128 | ||
129 | mutex_exit(&spa->spa_errlist_lock); | |
130 | } | |
131 | ||
132 | /* | |
133 | * Return the number of errors currently in the error log. This is actually the | |
134 | * sum of both the last log and the current log, since we don't know the union | |
135 | * of these logs until we reach userland. | |
136 | */ | |
137 | uint64_t | |
138 | spa_get_errlog_size(spa_t *spa) | |
139 | { | |
140 | uint64_t total = 0, count; | |
141 | ||
142 | mutex_enter(&spa->spa_errlog_lock); | |
143 | if (spa->spa_errlog_scrub != 0 && | |
144 | zap_count(spa->spa_meta_objset, spa->spa_errlog_scrub, | |
145 | &count) == 0) | |
146 | total += count; | |
147 | ||
148 | if (spa->spa_errlog_last != 0 && !spa->spa_scrub_finished && | |
149 | zap_count(spa->spa_meta_objset, spa->spa_errlog_last, | |
150 | &count) == 0) | |
151 | total += count; | |
152 | mutex_exit(&spa->spa_errlog_lock); | |
153 | ||
154 | mutex_enter(&spa->spa_errlist_lock); | |
155 | total += avl_numnodes(&spa->spa_errlist_last); | |
156 | total += avl_numnodes(&spa->spa_errlist_scrub); | |
157 | mutex_exit(&spa->spa_errlist_lock); | |
158 | ||
159 | return (total); | |
160 | } | |
161 | ||
162 | #ifdef _KERNEL | |
163 | static int | |
164 | process_error_log(spa_t *spa, uint64_t obj, void *addr, size_t *count) | |
165 | { | |
166 | zap_cursor_t zc; | |
167 | zap_attribute_t za; | |
ea04106b | 168 | zbookmark_phys_t zb; |
34dc7c2f BB |
169 | |
170 | if (obj == 0) | |
171 | return (0); | |
172 | ||
173 | for (zap_cursor_init(&zc, spa->spa_meta_objset, obj); | |
174 | zap_cursor_retrieve(&zc, &za) == 0; | |
175 | zap_cursor_advance(&zc)) { | |
176 | ||
177 | if (*count == 0) { | |
178 | zap_cursor_fini(&zc); | |
a08ee875 | 179 | return (SET_ERROR(ENOMEM)); |
34dc7c2f BB |
180 | } |
181 | ||
182 | name_to_bookmark(za.za_name, &zb); | |
183 | ||
184 | if (copyout(&zb, (char *)addr + | |
ea04106b AX |
185 | (*count - 1) * sizeof (zbookmark_phys_t), |
186 | sizeof (zbookmark_phys_t)) != 0) { | |
a08ee875 LG |
187 | zap_cursor_fini(&zc); |
188 | return (SET_ERROR(EFAULT)); | |
189 | } | |
34dc7c2f BB |
190 | |
191 | *count -= 1; | |
192 | } | |
193 | ||
194 | zap_cursor_fini(&zc); | |
195 | ||
196 | return (0); | |
197 | } | |
198 | ||
199 | static int | |
200 | process_error_list(avl_tree_t *list, void *addr, size_t *count) | |
201 | { | |
202 | spa_error_entry_t *se; | |
203 | ||
204 | for (se = avl_first(list); se != NULL; se = AVL_NEXT(list, se)) { | |
205 | ||
206 | if (*count == 0) | |
a08ee875 | 207 | return (SET_ERROR(ENOMEM)); |
34dc7c2f BB |
208 | |
209 | if (copyout(&se->se_bookmark, (char *)addr + | |
ea04106b AX |
210 | (*count - 1) * sizeof (zbookmark_phys_t), |
211 | sizeof (zbookmark_phys_t)) != 0) | |
a08ee875 | 212 | return (SET_ERROR(EFAULT)); |
34dc7c2f BB |
213 | |
214 | *count -= 1; | |
215 | } | |
216 | ||
217 | return (0); | |
218 | } | |
219 | #endif | |
220 | ||
221 | /* | |
222 | * Copy all known errors to userland as an array of bookmarks. This is | |
223 | * actually a union of the on-disk last log and current log, as well as any | |
224 | * pending error requests. | |
225 | * | |
226 | * Because the act of reading the on-disk log could cause errors to be | |
227 | * generated, we have two separate locks: one for the error log and one for the | |
228 | * in-core error lists. We only need the error list lock to log and error, so | |
229 | * we grab the error log lock while we read the on-disk logs, and only pick up | |
230 | * the error list lock when we are finished. | |
231 | */ | |
232 | int | |
233 | spa_get_errlog(spa_t *spa, void *uaddr, size_t *count) | |
234 | { | |
235 | int ret = 0; | |
236 | ||
237 | #ifdef _KERNEL | |
238 | mutex_enter(&spa->spa_errlog_lock); | |
239 | ||
240 | ret = process_error_log(spa, spa->spa_errlog_scrub, uaddr, count); | |
241 | ||
242 | if (!ret && !spa->spa_scrub_finished) | |
243 | ret = process_error_log(spa, spa->spa_errlog_last, uaddr, | |
244 | count); | |
245 | ||
246 | mutex_enter(&spa->spa_errlist_lock); | |
247 | if (!ret) | |
248 | ret = process_error_list(&spa->spa_errlist_scrub, uaddr, | |
249 | count); | |
250 | if (!ret) | |
251 | ret = process_error_list(&spa->spa_errlist_last, uaddr, | |
252 | count); | |
253 | mutex_exit(&spa->spa_errlist_lock); | |
254 | ||
255 | mutex_exit(&spa->spa_errlog_lock); | |
256 | #endif | |
257 | ||
258 | return (ret); | |
259 | } | |
260 | ||
261 | /* | |
262 | * Called when a scrub completes. This simply set a bit which tells which AVL | |
263 | * tree to add new errors. spa_errlog_sync() is responsible for actually | |
264 | * syncing the changes to the underlying objects. | |
265 | */ | |
266 | void | |
267 | spa_errlog_rotate(spa_t *spa) | |
268 | { | |
269 | mutex_enter(&spa->spa_errlist_lock); | |
34dc7c2f | 270 | spa->spa_scrub_finished = B_TRUE; |
34dc7c2f BB |
271 | mutex_exit(&spa->spa_errlist_lock); |
272 | } | |
273 | ||
274 | /* | |
275 | * Discard any pending errors from the spa_t. Called when unloading a faulted | |
276 | * pool, as the errors encountered during the open cannot be synced to disk. | |
277 | */ | |
278 | void | |
279 | spa_errlog_drain(spa_t *spa) | |
280 | { | |
281 | spa_error_entry_t *se; | |
282 | void *cookie; | |
283 | ||
284 | mutex_enter(&spa->spa_errlist_lock); | |
285 | ||
286 | cookie = NULL; | |
287 | while ((se = avl_destroy_nodes(&spa->spa_errlist_last, | |
288 | &cookie)) != NULL) | |
289 | kmem_free(se, sizeof (spa_error_entry_t)); | |
290 | cookie = NULL; | |
291 | while ((se = avl_destroy_nodes(&spa->spa_errlist_scrub, | |
292 | &cookie)) != NULL) | |
293 | kmem_free(se, sizeof (spa_error_entry_t)); | |
294 | ||
295 | mutex_exit(&spa->spa_errlist_lock); | |
296 | } | |
297 | ||
298 | /* | |
299 | * Process a list of errors into the current on-disk log. | |
300 | */ | |
301 | static void | |
302 | sync_error_list(spa_t *spa, avl_tree_t *t, uint64_t *obj, dmu_tx_t *tx) | |
303 | { | |
304 | spa_error_entry_t *se; | |
305 | char buf[64]; | |
306 | void *cookie; | |
307 | ||
308 | if (avl_numnodes(t) != 0) { | |
309 | /* create log if necessary */ | |
310 | if (*obj == 0) | |
311 | *obj = zap_create(spa->spa_meta_objset, | |
312 | DMU_OT_ERROR_LOG, DMU_OT_NONE, | |
313 | 0, tx); | |
314 | ||
315 | /* add errors to the current log */ | |
316 | for (se = avl_first(t); se != NULL; se = AVL_NEXT(t, se)) { | |
317 | char *name = se->se_name ? se->se_name : ""; | |
318 | ||
319 | bookmark_to_name(&se->se_bookmark, buf, sizeof (buf)); | |
320 | ||
321 | (void) zap_update(spa->spa_meta_objset, | |
322 | *obj, buf, 1, strlen(name) + 1, name, tx); | |
323 | } | |
324 | ||
325 | /* purge the error list */ | |
326 | cookie = NULL; | |
327 | while ((se = avl_destroy_nodes(t, &cookie)) != NULL) | |
328 | kmem_free(se, sizeof (spa_error_entry_t)); | |
329 | } | |
330 | } | |
331 | ||
332 | /* | |
333 | * Sync the error log out to disk. This is a little tricky because the act of | |
334 | * writing the error log requires the spa_errlist_lock. So, we need to lock the | |
335 | * error lists, take a copy of the lists, and then reinitialize them. Then, we | |
336 | * drop the error list lock and take the error log lock, at which point we | |
337 | * do the errlog processing. Then, if we encounter an I/O error during this | |
338 | * process, we can successfully add the error to the list. Note that this will | |
339 | * result in the perpetual recycling of errors, but it is an unlikely situation | |
340 | * and not a performance critical operation. | |
341 | */ | |
342 | void | |
343 | spa_errlog_sync(spa_t *spa, uint64_t txg) | |
344 | { | |
345 | dmu_tx_t *tx; | |
346 | avl_tree_t scrub, last; | |
347 | int scrub_finished; | |
348 | ||
349 | mutex_enter(&spa->spa_errlist_lock); | |
350 | ||
351 | /* | |
352 | * Bail out early under normal circumstances. | |
353 | */ | |
354 | if (avl_numnodes(&spa->spa_errlist_scrub) == 0 && | |
355 | avl_numnodes(&spa->spa_errlist_last) == 0 && | |
356 | !spa->spa_scrub_finished) { | |
357 | mutex_exit(&spa->spa_errlist_lock); | |
358 | return; | |
359 | } | |
360 | ||
361 | spa_get_errlists(spa, &last, &scrub); | |
362 | scrub_finished = spa->spa_scrub_finished; | |
363 | spa->spa_scrub_finished = B_FALSE; | |
364 | ||
365 | mutex_exit(&spa->spa_errlist_lock); | |
366 | mutex_enter(&spa->spa_errlog_lock); | |
367 | ||
368 | tx = dmu_tx_create_assigned(spa->spa_dsl_pool, txg); | |
369 | ||
370 | /* | |
371 | * Sync out the current list of errors. | |
372 | */ | |
373 | sync_error_list(spa, &last, &spa->spa_errlog_last, tx); | |
374 | ||
375 | /* | |
376 | * Rotate the log if necessary. | |
377 | */ | |
378 | if (scrub_finished) { | |
379 | if (spa->spa_errlog_last != 0) | |
380 | VERIFY(dmu_object_free(spa->spa_meta_objset, | |
381 | spa->spa_errlog_last, tx) == 0); | |
382 | spa->spa_errlog_last = spa->spa_errlog_scrub; | |
383 | spa->spa_errlog_scrub = 0; | |
384 | ||
385 | sync_error_list(spa, &scrub, &spa->spa_errlog_last, tx); | |
386 | } | |
387 | ||
388 | /* | |
389 | * Sync out any pending scrub errors. | |
390 | */ | |
391 | sync_error_list(spa, &scrub, &spa->spa_errlog_scrub, tx); | |
392 | ||
393 | /* | |
394 | * Update the MOS to reflect the new values. | |
395 | */ | |
396 | (void) zap_update(spa->spa_meta_objset, DMU_POOL_DIRECTORY_OBJECT, | |
397 | DMU_POOL_ERRLOG_LAST, sizeof (uint64_t), 1, | |
398 | &spa->spa_errlog_last, tx); | |
399 | (void) zap_update(spa->spa_meta_objset, DMU_POOL_DIRECTORY_OBJECT, | |
400 | DMU_POOL_ERRLOG_SCRUB, sizeof (uint64_t), 1, | |
401 | &spa->spa_errlog_scrub, tx); | |
402 | ||
403 | dmu_tx_commit(tx); | |
404 | ||
405 | mutex_exit(&spa->spa_errlog_lock); | |
406 | } | |
c28b2279 BB |
407 | |
408 | #if defined(_KERNEL) && defined(HAVE_SPL) | |
409 | /* error handling */ | |
410 | EXPORT_SYMBOL(spa_log_error); | |
411 | EXPORT_SYMBOL(spa_get_errlog_size); | |
412 | EXPORT_SYMBOL(spa_get_errlog); | |
413 | EXPORT_SYMBOL(spa_errlog_rotate); | |
414 | EXPORT_SYMBOL(spa_errlog_drain); | |
415 | EXPORT_SYMBOL(spa_errlog_sync); | |
416 | EXPORT_SYMBOL(spa_get_errlists); | |
417 | #endif |