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a2de733c AJ |
1 | /* |
2 | * Copyright (C) 2011 STRATO. All rights reserved. | |
3 | * | |
4 | * This program is free software; you can redistribute it and/or | |
5 | * modify it under the terms of the GNU General Public | |
6 | * License v2 as published by the Free Software Foundation. | |
7 | * | |
8 | * This program is distributed in the hope that it will be useful, | |
9 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
10 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
11 | * General Public License for more details. | |
12 | * | |
13 | * You should have received a copy of the GNU General Public | |
14 | * License along with this program; if not, write to the | |
15 | * Free Software Foundation, Inc., 59 Temple Place - Suite 330, | |
16 | * Boston, MA 021110-1307, USA. | |
17 | */ | |
18 | ||
19 | #include <linux/sched.h> | |
20 | #include <linux/pagemap.h> | |
21 | #include <linux/writeback.h> | |
22 | #include <linux/blkdev.h> | |
23 | #include <linux/rbtree.h> | |
24 | #include <linux/slab.h> | |
25 | #include <linux/workqueue.h> | |
26 | #include "ctree.h" | |
27 | #include "volumes.h" | |
28 | #include "disk-io.h" | |
29 | #include "ordered-data.h" | |
30 | ||
31 | /* | |
32 | * This is only the first step towards a full-features scrub. It reads all | |
33 | * extent and super block and verifies the checksums. In case a bad checksum | |
34 | * is found or the extent cannot be read, good data will be written back if | |
35 | * any can be found. | |
36 | * | |
37 | * Future enhancements: | |
38 | * - To enhance the performance, better read-ahead strategies for the | |
39 | * extent-tree can be employed. | |
40 | * - In case an unrepairable extent is encountered, track which files are | |
41 | * affected and report them | |
42 | * - In case of a read error on files with nodatasum, map the file and read | |
43 | * the extent to trigger a writeback of the good copy | |
44 | * - track and record media errors, throw out bad devices | |
45 | * - add a readonly mode | |
46 | * - add a mode to also read unallocated space | |
47 | * - make the prefetch cancellable | |
48 | */ | |
49 | ||
50 | struct scrub_bio; | |
51 | struct scrub_page; | |
52 | struct scrub_dev; | |
53 | struct scrub_fixup; | |
54 | static void scrub_bio_end_io(struct bio *bio, int err); | |
55 | static void scrub_checksum(struct btrfs_work *work); | |
56 | static int scrub_checksum_data(struct scrub_dev *sdev, | |
57 | struct scrub_page *spag, void *buffer); | |
58 | static int scrub_checksum_tree_block(struct scrub_dev *sdev, | |
59 | struct scrub_page *spag, u64 logical, | |
60 | void *buffer); | |
61 | static int scrub_checksum_super(struct scrub_bio *sbio, void *buffer); | |
62 | static void scrub_recheck_end_io(struct bio *bio, int err); | |
63 | static void scrub_fixup_worker(struct btrfs_work *work); | |
64 | static void scrub_fixup(struct scrub_fixup *fixup); | |
65 | ||
66 | #define SCRUB_PAGES_PER_BIO 16 /* 64k per bio */ | |
67 | #define SCRUB_BIOS_PER_DEV 16 /* 1 MB per device in flight */ | |
68 | ||
69 | struct scrub_page { | |
70 | u64 flags; /* extent flags */ | |
71 | u64 generation; | |
72 | u64 mirror_num; | |
73 | int have_csum; | |
74 | u8 csum[BTRFS_CSUM_SIZE]; | |
75 | }; | |
76 | ||
77 | struct scrub_bio { | |
78 | int index; | |
79 | struct scrub_dev *sdev; | |
80 | struct bio *bio; | |
81 | int err; | |
82 | u64 logical; | |
83 | u64 physical; | |
84 | struct scrub_page spag[SCRUB_PAGES_PER_BIO]; | |
85 | u64 count; | |
86 | int next_free; | |
87 | struct btrfs_work work; | |
88 | }; | |
89 | ||
90 | struct scrub_dev { | |
91 | struct scrub_bio *bios[SCRUB_BIOS_PER_DEV]; | |
92 | struct btrfs_device *dev; | |
93 | int first_free; | |
94 | int curr; | |
95 | atomic_t in_flight; | |
96 | spinlock_t list_lock; | |
97 | wait_queue_head_t list_wait; | |
98 | u16 csum_size; | |
99 | struct list_head csum_list; | |
100 | atomic_t cancel_req; | |
101 | /* | |
102 | * statistics | |
103 | */ | |
104 | struct btrfs_scrub_progress stat; | |
105 | spinlock_t stat_lock; | |
106 | }; | |
107 | ||
108 | struct scrub_fixup { | |
109 | struct scrub_dev *sdev; | |
110 | struct bio *bio; | |
111 | u64 logical; | |
112 | u64 physical; | |
113 | struct scrub_page spag; | |
114 | struct btrfs_work work; | |
115 | int err; | |
116 | int recheck; | |
117 | }; | |
118 | ||
119 | static void scrub_free_csums(struct scrub_dev *sdev) | |
120 | { | |
121 | while (!list_empty(&sdev->csum_list)) { | |
122 | struct btrfs_ordered_sum *sum; | |
123 | sum = list_first_entry(&sdev->csum_list, | |
124 | struct btrfs_ordered_sum, list); | |
125 | list_del(&sum->list); | |
126 | kfree(sum); | |
127 | } | |
128 | } | |
129 | ||
130 | static noinline_for_stack void scrub_free_dev(struct scrub_dev *sdev) | |
131 | { | |
132 | int i; | |
133 | int j; | |
134 | struct page *last_page; | |
135 | ||
136 | if (!sdev) | |
137 | return; | |
138 | ||
139 | for (i = 0; i < SCRUB_BIOS_PER_DEV; ++i) { | |
140 | struct scrub_bio *sbio = sdev->bios[i]; | |
141 | struct bio *bio; | |
142 | ||
143 | if (!sbio) | |
144 | break; | |
145 | ||
146 | bio = sbio->bio; | |
147 | if (bio) { | |
148 | last_page = NULL; | |
149 | for (j = 0; j < bio->bi_vcnt; ++j) { | |
150 | if (bio->bi_io_vec[j].bv_page == last_page) | |
151 | continue; | |
152 | last_page = bio->bi_io_vec[j].bv_page; | |
153 | __free_page(last_page); | |
154 | } | |
155 | bio_put(bio); | |
156 | } | |
157 | kfree(sbio); | |
158 | } | |
159 | ||
160 | scrub_free_csums(sdev); | |
161 | kfree(sdev); | |
162 | } | |
163 | ||
164 | static noinline_for_stack | |
165 | struct scrub_dev *scrub_setup_dev(struct btrfs_device *dev) | |
166 | { | |
167 | struct scrub_dev *sdev; | |
168 | int i; | |
169 | int j; | |
170 | int ret; | |
171 | struct btrfs_fs_info *fs_info = dev->dev_root->fs_info; | |
172 | ||
173 | sdev = kzalloc(sizeof(*sdev), GFP_NOFS); | |
174 | if (!sdev) | |
175 | goto nomem; | |
176 | sdev->dev = dev; | |
177 | for (i = 0; i < SCRUB_BIOS_PER_DEV; ++i) { | |
178 | struct bio *bio; | |
179 | struct scrub_bio *sbio; | |
180 | ||
181 | sbio = kzalloc(sizeof(*sbio), GFP_NOFS); | |
182 | if (!sbio) | |
183 | goto nomem; | |
184 | sdev->bios[i] = sbio; | |
185 | ||
186 | bio = bio_kmalloc(GFP_NOFS, SCRUB_PAGES_PER_BIO); | |
187 | if (!bio) | |
188 | goto nomem; | |
189 | ||
190 | sbio->index = i; | |
191 | sbio->sdev = sdev; | |
192 | sbio->bio = bio; | |
193 | sbio->count = 0; | |
194 | sbio->work.func = scrub_checksum; | |
195 | bio->bi_private = sdev->bios[i]; | |
196 | bio->bi_end_io = scrub_bio_end_io; | |
197 | bio->bi_sector = 0; | |
198 | bio->bi_bdev = dev->bdev; | |
199 | bio->bi_size = 0; | |
200 | ||
201 | for (j = 0; j < SCRUB_PAGES_PER_BIO; ++j) { | |
202 | struct page *page; | |
203 | page = alloc_page(GFP_NOFS); | |
204 | if (!page) | |
205 | goto nomem; | |
206 | ||
207 | ret = bio_add_page(bio, page, PAGE_SIZE, 0); | |
208 | if (!ret) | |
209 | goto nomem; | |
210 | } | |
211 | WARN_ON(bio->bi_vcnt != SCRUB_PAGES_PER_BIO); | |
212 | ||
213 | if (i != SCRUB_BIOS_PER_DEV-1) | |
214 | sdev->bios[i]->next_free = i + 1; | |
215 | else | |
216 | sdev->bios[i]->next_free = -1; | |
217 | } | |
218 | sdev->first_free = 0; | |
219 | sdev->curr = -1; | |
220 | atomic_set(&sdev->in_flight, 0); | |
221 | atomic_set(&sdev->cancel_req, 0); | |
222 | sdev->csum_size = btrfs_super_csum_size(&fs_info->super_copy); | |
223 | INIT_LIST_HEAD(&sdev->csum_list); | |
224 | ||
225 | spin_lock_init(&sdev->list_lock); | |
226 | spin_lock_init(&sdev->stat_lock); | |
227 | init_waitqueue_head(&sdev->list_wait); | |
228 | return sdev; | |
229 | ||
230 | nomem: | |
231 | scrub_free_dev(sdev); | |
232 | return ERR_PTR(-ENOMEM); | |
233 | } | |
234 | ||
235 | /* | |
236 | * scrub_recheck_error gets called when either verification of the page | |
237 | * failed or the bio failed to read, e.g. with EIO. In the latter case, | |
238 | * recheck_error gets called for every page in the bio, even though only | |
239 | * one may be bad | |
240 | */ | |
241 | static void scrub_recheck_error(struct scrub_bio *sbio, int ix) | |
242 | { | |
243 | struct scrub_dev *sdev = sbio->sdev; | |
244 | struct btrfs_fs_info *fs_info = sdev->dev->dev_root->fs_info; | |
245 | struct bio *bio = NULL; | |
246 | struct page *page = NULL; | |
247 | struct scrub_fixup *fixup = NULL; | |
248 | int ret; | |
249 | ||
250 | /* | |
251 | * while we're in here we do not want the transaction to commit. | |
252 | * To prevent it, we increment scrubs_running. scrub_pause will | |
253 | * have to wait until we're finished | |
254 | * we can safely increment scrubs_running here, because we're | |
255 | * in the context of the original bio which is still marked in_flight | |
256 | */ | |
257 | atomic_inc(&fs_info->scrubs_running); | |
258 | ||
259 | fixup = kzalloc(sizeof(*fixup), GFP_NOFS); | |
260 | if (!fixup) | |
261 | goto malloc_error; | |
262 | ||
263 | fixup->logical = sbio->logical + ix * PAGE_SIZE; | |
264 | fixup->physical = sbio->physical + ix * PAGE_SIZE; | |
265 | fixup->spag = sbio->spag[ix]; | |
266 | fixup->sdev = sdev; | |
267 | ||
268 | bio = bio_alloc(GFP_NOFS, 1); | |
269 | if (!bio) | |
270 | goto malloc_error; | |
271 | bio->bi_private = fixup; | |
272 | bio->bi_size = 0; | |
273 | bio->bi_bdev = sdev->dev->bdev; | |
274 | fixup->bio = bio; | |
275 | fixup->recheck = 0; | |
276 | ||
277 | page = alloc_page(GFP_NOFS); | |
278 | if (!page) | |
279 | goto malloc_error; | |
280 | ||
281 | ret = bio_add_page(bio, page, PAGE_SIZE, 0); | |
282 | if (!ret) | |
283 | goto malloc_error; | |
284 | ||
285 | if (!sbio->err) { | |
286 | /* | |
287 | * shorter path: just a checksum error, go ahead and correct it | |
288 | */ | |
289 | scrub_fixup_worker(&fixup->work); | |
290 | return; | |
291 | } | |
292 | ||
293 | /* | |
294 | * an I/O-error occured for one of the blocks in the bio, not | |
295 | * necessarily for this one, so first try to read it separately | |
296 | */ | |
297 | fixup->work.func = scrub_fixup_worker; | |
298 | fixup->recheck = 1; | |
299 | bio->bi_end_io = scrub_recheck_end_io; | |
300 | bio->bi_sector = fixup->physical >> 9; | |
301 | bio->bi_bdev = sdev->dev->bdev; | |
302 | submit_bio(0, bio); | |
303 | ||
304 | return; | |
305 | ||
306 | malloc_error: | |
307 | if (bio) | |
308 | bio_put(bio); | |
309 | if (page) | |
310 | __free_page(page); | |
311 | kfree(fixup); | |
312 | spin_lock(&sdev->stat_lock); | |
313 | ++sdev->stat.malloc_errors; | |
314 | spin_unlock(&sdev->stat_lock); | |
315 | atomic_dec(&fs_info->scrubs_running); | |
316 | wake_up(&fs_info->scrub_pause_wait); | |
317 | } | |
318 | ||
319 | static void scrub_recheck_end_io(struct bio *bio, int err) | |
320 | { | |
321 | struct scrub_fixup *fixup = bio->bi_private; | |
322 | struct btrfs_fs_info *fs_info = fixup->sdev->dev->dev_root->fs_info; | |
323 | ||
324 | fixup->err = err; | |
325 | btrfs_queue_worker(&fs_info->scrub_workers, &fixup->work); | |
326 | } | |
327 | ||
328 | static int scrub_fixup_check(struct scrub_fixup *fixup) | |
329 | { | |
330 | int ret = 1; | |
331 | struct page *page; | |
332 | void *buffer; | |
333 | u64 flags = fixup->spag.flags; | |
334 | ||
335 | page = fixup->bio->bi_io_vec[0].bv_page; | |
336 | buffer = kmap_atomic(page, KM_USER0); | |
337 | if (flags & BTRFS_EXTENT_FLAG_DATA) { | |
338 | ret = scrub_checksum_data(fixup->sdev, | |
339 | &fixup->spag, buffer); | |
340 | } else if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) { | |
341 | ret = scrub_checksum_tree_block(fixup->sdev, | |
342 | &fixup->spag, | |
343 | fixup->logical, | |
344 | buffer); | |
345 | } else { | |
346 | WARN_ON(1); | |
347 | } | |
348 | kunmap_atomic(buffer, KM_USER0); | |
349 | ||
350 | return ret; | |
351 | } | |
352 | ||
353 | static void scrub_fixup_worker(struct btrfs_work *work) | |
354 | { | |
355 | struct scrub_fixup *fixup; | |
356 | struct btrfs_fs_info *fs_info; | |
357 | u64 flags; | |
358 | int ret = 1; | |
359 | ||
360 | fixup = container_of(work, struct scrub_fixup, work); | |
361 | fs_info = fixup->sdev->dev->dev_root->fs_info; | |
362 | flags = fixup->spag.flags; | |
363 | ||
364 | if (fixup->recheck && fixup->err == 0) | |
365 | ret = scrub_fixup_check(fixup); | |
366 | ||
367 | if (ret || fixup->err) | |
368 | scrub_fixup(fixup); | |
369 | ||
370 | __free_page(fixup->bio->bi_io_vec[0].bv_page); | |
371 | bio_put(fixup->bio); | |
372 | ||
373 | atomic_dec(&fs_info->scrubs_running); | |
374 | wake_up(&fs_info->scrub_pause_wait); | |
375 | ||
376 | kfree(fixup); | |
377 | } | |
378 | ||
379 | static void scrub_fixup_end_io(struct bio *bio, int err) | |
380 | { | |
381 | complete((struct completion *)bio->bi_private); | |
382 | } | |
383 | ||
384 | static void scrub_fixup(struct scrub_fixup *fixup) | |
385 | { | |
386 | struct scrub_dev *sdev = fixup->sdev; | |
387 | struct btrfs_fs_info *fs_info = sdev->dev->dev_root->fs_info; | |
388 | struct btrfs_mapping_tree *map_tree = &fs_info->mapping_tree; | |
389 | struct btrfs_multi_bio *multi = NULL; | |
390 | struct bio *bio = fixup->bio; | |
391 | u64 length; | |
392 | int i; | |
393 | int ret; | |
394 | DECLARE_COMPLETION_ONSTACK(complete); | |
395 | ||
396 | if ((fixup->spag.flags & BTRFS_EXTENT_FLAG_DATA) && | |
397 | (fixup->spag.have_csum == 0)) { | |
398 | /* | |
399 | * nodatasum, don't try to fix anything | |
400 | * FIXME: we can do better, open the inode and trigger a | |
401 | * writeback | |
402 | */ | |
403 | goto uncorrectable; | |
404 | } | |
405 | ||
406 | length = PAGE_SIZE; | |
407 | ret = btrfs_map_block(map_tree, REQ_WRITE, fixup->logical, &length, | |
408 | &multi, 0); | |
409 | if (ret || !multi || length < PAGE_SIZE) { | |
410 | printk(KERN_ERR | |
411 | "scrub_fixup: btrfs_map_block failed us for %llu\n", | |
412 | (unsigned long long)fixup->logical); | |
413 | WARN_ON(1); | |
414 | return; | |
415 | } | |
416 | ||
417 | if (multi->num_stripes == 1) { | |
418 | /* there aren't any replicas */ | |
419 | goto uncorrectable; | |
420 | } | |
421 | ||
422 | /* | |
423 | * first find a good copy | |
424 | */ | |
425 | for (i = 0; i < multi->num_stripes; ++i) { | |
426 | if (i == fixup->spag.mirror_num) | |
427 | continue; | |
428 | ||
429 | bio->bi_sector = multi->stripes[i].physical >> 9; | |
430 | bio->bi_bdev = multi->stripes[i].dev->bdev; | |
431 | bio->bi_size = PAGE_SIZE; | |
432 | bio->bi_next = NULL; | |
433 | bio->bi_flags |= 1 << BIO_UPTODATE; | |
434 | bio->bi_comp_cpu = -1; | |
435 | bio->bi_end_io = scrub_fixup_end_io; | |
436 | bio->bi_private = &complete; | |
437 | ||
438 | submit_bio(0, bio); | |
439 | ||
440 | wait_for_completion(&complete); | |
441 | ||
442 | if (!test_bit(BIO_UPTODATE, &bio->bi_flags)) | |
443 | /* I/O-error, this is not a good copy */ | |
444 | continue; | |
445 | ||
446 | ret = scrub_fixup_check(fixup); | |
447 | if (ret == 0) | |
448 | break; | |
449 | } | |
450 | if (i == multi->num_stripes) | |
451 | goto uncorrectable; | |
452 | ||
453 | /* | |
454 | * the bio now contains good data, write it back | |
455 | */ | |
456 | bio->bi_sector = fixup->physical >> 9; | |
457 | bio->bi_bdev = sdev->dev->bdev; | |
458 | bio->bi_size = PAGE_SIZE; | |
459 | bio->bi_next = NULL; | |
460 | bio->bi_flags |= 1 << BIO_UPTODATE; | |
461 | bio->bi_comp_cpu = -1; | |
462 | bio->bi_end_io = scrub_fixup_end_io; | |
463 | bio->bi_private = &complete; | |
464 | ||
465 | submit_bio(REQ_WRITE, bio); | |
466 | ||
467 | wait_for_completion(&complete); | |
468 | ||
469 | if (!test_bit(BIO_UPTODATE, &bio->bi_flags)) | |
470 | /* I/O-error, writeback failed, give up */ | |
471 | goto uncorrectable; | |
472 | ||
473 | kfree(multi); | |
474 | spin_lock(&sdev->stat_lock); | |
475 | ++sdev->stat.corrected_errors; | |
476 | spin_unlock(&sdev->stat_lock); | |
477 | ||
478 | if (printk_ratelimit()) | |
479 | printk(KERN_ERR "btrfs: fixed up at %llu\n", | |
480 | (unsigned long long)fixup->logical); | |
481 | return; | |
482 | ||
483 | uncorrectable: | |
484 | kfree(multi); | |
485 | spin_lock(&sdev->stat_lock); | |
486 | ++sdev->stat.uncorrectable_errors; | |
487 | spin_unlock(&sdev->stat_lock); | |
488 | ||
489 | if (printk_ratelimit()) | |
490 | printk(KERN_ERR "btrfs: unable to fixup at %llu\n", | |
491 | (unsigned long long)fixup->logical); | |
492 | } | |
493 | ||
494 | static void scrub_bio_end_io(struct bio *bio, int err) | |
495 | { | |
496 | struct scrub_bio *sbio = bio->bi_private; | |
497 | struct scrub_dev *sdev = sbio->sdev; | |
498 | struct btrfs_fs_info *fs_info = sdev->dev->dev_root->fs_info; | |
499 | ||
500 | sbio->err = err; | |
501 | ||
502 | btrfs_queue_worker(&fs_info->scrub_workers, &sbio->work); | |
503 | } | |
504 | ||
505 | static void scrub_checksum(struct btrfs_work *work) | |
506 | { | |
507 | struct scrub_bio *sbio = container_of(work, struct scrub_bio, work); | |
508 | struct scrub_dev *sdev = sbio->sdev; | |
509 | struct page *page; | |
510 | void *buffer; | |
511 | int i; | |
512 | u64 flags; | |
513 | u64 logical; | |
514 | int ret; | |
515 | ||
516 | if (sbio->err) { | |
517 | struct bio *bio; | |
518 | struct bio *old_bio; | |
519 | ||
520 | for (i = 0; i < sbio->count; ++i) | |
521 | scrub_recheck_error(sbio, i); | |
522 | spin_lock(&sdev->stat_lock); | |
523 | ++sdev->stat.read_errors; | |
524 | spin_unlock(&sdev->stat_lock); | |
525 | ||
526 | /* | |
527 | * FIXME: allocate a new bio after a media error. I haven't | |
528 | * figured out how to reuse this one | |
529 | */ | |
530 | old_bio = sbio->bio; | |
531 | bio = bio_kmalloc(GFP_NOFS, SCRUB_PAGES_PER_BIO); | |
532 | if (!bio) { | |
533 | /* | |
534 | * alloc failed. cancel the scrub and don't requeue | |
535 | * this sbio | |
536 | */ | |
537 | printk(KERN_ERR "btrfs scrub: allocation failure, " | |
538 | "cancelling scrub\n"); | |
539 | atomic_inc(&sdev->dev->dev_root->fs_info-> | |
540 | scrub_cancel_req); | |
541 | goto out_no_enqueue; | |
542 | } | |
543 | sbio->bio = bio; | |
544 | bio->bi_private = sbio; | |
545 | bio->bi_end_io = scrub_bio_end_io; | |
546 | bio->bi_sector = 0; | |
547 | bio->bi_bdev = sbio->sdev->dev->bdev; | |
548 | bio->bi_size = 0; | |
549 | for (i = 0; i < SCRUB_PAGES_PER_BIO; ++i) { | |
550 | struct page *page; | |
551 | page = old_bio->bi_io_vec[i].bv_page; | |
552 | bio_add_page(bio, page, PAGE_SIZE, 0); | |
553 | } | |
554 | bio_put(old_bio); | |
555 | goto out; | |
556 | } | |
557 | for (i = 0; i < sbio->count; ++i) { | |
558 | page = sbio->bio->bi_io_vec[i].bv_page; | |
559 | buffer = kmap_atomic(page, KM_USER0); | |
560 | flags = sbio->spag[i].flags; | |
561 | logical = sbio->logical + i * PAGE_SIZE; | |
562 | ret = 0; | |
563 | if (flags & BTRFS_EXTENT_FLAG_DATA) { | |
564 | ret = scrub_checksum_data(sdev, sbio->spag + i, buffer); | |
565 | } else if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) { | |
566 | ret = scrub_checksum_tree_block(sdev, sbio->spag + i, | |
567 | logical, buffer); | |
568 | } else if (flags & BTRFS_EXTENT_FLAG_SUPER) { | |
569 | BUG_ON(i); | |
570 | (void)scrub_checksum_super(sbio, buffer); | |
571 | } else { | |
572 | WARN_ON(1); | |
573 | } | |
574 | kunmap_atomic(buffer, KM_USER0); | |
575 | if (ret) | |
576 | scrub_recheck_error(sbio, i); | |
577 | } | |
578 | ||
579 | out: | |
580 | spin_lock(&sdev->list_lock); | |
581 | sbio->next_free = sdev->first_free; | |
582 | sdev->first_free = sbio->index; | |
583 | spin_unlock(&sdev->list_lock); | |
584 | out_no_enqueue: | |
585 | atomic_dec(&sdev->in_flight); | |
586 | wake_up(&sdev->list_wait); | |
587 | } | |
588 | ||
589 | static int scrub_checksum_data(struct scrub_dev *sdev, | |
590 | struct scrub_page *spag, void *buffer) | |
591 | { | |
592 | u8 csum[BTRFS_CSUM_SIZE]; | |
593 | u32 crc = ~(u32)0; | |
594 | int fail = 0; | |
595 | struct btrfs_root *root = sdev->dev->dev_root; | |
596 | ||
597 | if (!spag->have_csum) | |
598 | return 0; | |
599 | ||
600 | crc = btrfs_csum_data(root, buffer, crc, PAGE_SIZE); | |
601 | btrfs_csum_final(crc, csum); | |
602 | if (memcmp(csum, spag->csum, sdev->csum_size)) | |
603 | fail = 1; | |
604 | ||
605 | spin_lock(&sdev->stat_lock); | |
606 | ++sdev->stat.data_extents_scrubbed; | |
607 | sdev->stat.data_bytes_scrubbed += PAGE_SIZE; | |
608 | if (fail) | |
609 | ++sdev->stat.csum_errors; | |
610 | spin_unlock(&sdev->stat_lock); | |
611 | ||
612 | return fail; | |
613 | } | |
614 | ||
615 | static int scrub_checksum_tree_block(struct scrub_dev *sdev, | |
616 | struct scrub_page *spag, u64 logical, | |
617 | void *buffer) | |
618 | { | |
619 | struct btrfs_header *h; | |
620 | struct btrfs_root *root = sdev->dev->dev_root; | |
621 | struct btrfs_fs_info *fs_info = root->fs_info; | |
622 | u8 csum[BTRFS_CSUM_SIZE]; | |
623 | u32 crc = ~(u32)0; | |
624 | int fail = 0; | |
625 | int crc_fail = 0; | |
626 | ||
627 | /* | |
628 | * we don't use the getter functions here, as we | |
629 | * a) don't have an extent buffer and | |
630 | * b) the page is already kmapped | |
631 | */ | |
632 | h = (struct btrfs_header *)buffer; | |
633 | ||
634 | if (logical != le64_to_cpu(h->bytenr)) | |
635 | ++fail; | |
636 | ||
637 | if (spag->generation != le64_to_cpu(h->generation)) | |
638 | ++fail; | |
639 | ||
640 | if (memcmp(h->fsid, fs_info->fsid, BTRFS_UUID_SIZE)) | |
641 | ++fail; | |
642 | ||
643 | if (memcmp(h->chunk_tree_uuid, fs_info->chunk_tree_uuid, | |
644 | BTRFS_UUID_SIZE)) | |
645 | ++fail; | |
646 | ||
647 | crc = btrfs_csum_data(root, buffer + BTRFS_CSUM_SIZE, crc, | |
648 | PAGE_SIZE - BTRFS_CSUM_SIZE); | |
649 | btrfs_csum_final(crc, csum); | |
650 | if (memcmp(csum, h->csum, sdev->csum_size)) | |
651 | ++crc_fail; | |
652 | ||
653 | spin_lock(&sdev->stat_lock); | |
654 | ++sdev->stat.tree_extents_scrubbed; | |
655 | sdev->stat.tree_bytes_scrubbed += PAGE_SIZE; | |
656 | if (crc_fail) | |
657 | ++sdev->stat.csum_errors; | |
658 | if (fail) | |
659 | ++sdev->stat.verify_errors; | |
660 | spin_unlock(&sdev->stat_lock); | |
661 | ||
662 | return fail || crc_fail; | |
663 | } | |
664 | ||
665 | static int scrub_checksum_super(struct scrub_bio *sbio, void *buffer) | |
666 | { | |
667 | struct btrfs_super_block *s; | |
668 | u64 logical; | |
669 | struct scrub_dev *sdev = sbio->sdev; | |
670 | struct btrfs_root *root = sdev->dev->dev_root; | |
671 | struct btrfs_fs_info *fs_info = root->fs_info; | |
672 | u8 csum[BTRFS_CSUM_SIZE]; | |
673 | u32 crc = ~(u32)0; | |
674 | int fail = 0; | |
675 | ||
676 | s = (struct btrfs_super_block *)buffer; | |
677 | logical = sbio->logical; | |
678 | ||
679 | if (logical != le64_to_cpu(s->bytenr)) | |
680 | ++fail; | |
681 | ||
682 | if (sbio->spag[0].generation != le64_to_cpu(s->generation)) | |
683 | ++fail; | |
684 | ||
685 | if (memcmp(s->fsid, fs_info->fsid, BTRFS_UUID_SIZE)) | |
686 | ++fail; | |
687 | ||
688 | crc = btrfs_csum_data(root, buffer + BTRFS_CSUM_SIZE, crc, | |
689 | PAGE_SIZE - BTRFS_CSUM_SIZE); | |
690 | btrfs_csum_final(crc, csum); | |
691 | if (memcmp(csum, s->csum, sbio->sdev->csum_size)) | |
692 | ++fail; | |
693 | ||
694 | if (fail) { | |
695 | /* | |
696 | * if we find an error in a super block, we just report it. | |
697 | * They will get written with the next transaction commit | |
698 | * anyway | |
699 | */ | |
700 | spin_lock(&sdev->stat_lock); | |
701 | ++sdev->stat.super_errors; | |
702 | spin_unlock(&sdev->stat_lock); | |
703 | } | |
704 | ||
705 | return fail; | |
706 | } | |
707 | ||
708 | static int scrub_submit(struct scrub_dev *sdev) | |
709 | { | |
710 | struct scrub_bio *sbio; | |
711 | ||
712 | if (sdev->curr == -1) | |
713 | return 0; | |
714 | ||
715 | sbio = sdev->bios[sdev->curr]; | |
716 | ||
717 | sbio->bio->bi_sector = sbio->physical >> 9; | |
718 | sbio->bio->bi_size = sbio->count * PAGE_SIZE; | |
719 | sbio->bio->bi_next = NULL; | |
720 | sbio->bio->bi_flags |= 1 << BIO_UPTODATE; | |
721 | sbio->bio->bi_comp_cpu = -1; | |
722 | sbio->bio->bi_bdev = sdev->dev->bdev; | |
723 | sbio->err = 0; | |
724 | sdev->curr = -1; | |
725 | atomic_inc(&sdev->in_flight); | |
726 | ||
727 | submit_bio(0, sbio->bio); | |
728 | ||
729 | return 0; | |
730 | } | |
731 | ||
732 | static int scrub_page(struct scrub_dev *sdev, u64 logical, u64 len, | |
733 | u64 physical, u64 flags, u64 gen, u64 mirror_num, | |
734 | u8 *csum, int force) | |
735 | { | |
736 | struct scrub_bio *sbio; | |
737 | ||
738 | again: | |
739 | /* | |
740 | * grab a fresh bio or wait for one to become available | |
741 | */ | |
742 | while (sdev->curr == -1) { | |
743 | spin_lock(&sdev->list_lock); | |
744 | sdev->curr = sdev->first_free; | |
745 | if (sdev->curr != -1) { | |
746 | sdev->first_free = sdev->bios[sdev->curr]->next_free; | |
747 | sdev->bios[sdev->curr]->next_free = -1; | |
748 | sdev->bios[sdev->curr]->count = 0; | |
749 | spin_unlock(&sdev->list_lock); | |
750 | } else { | |
751 | spin_unlock(&sdev->list_lock); | |
752 | wait_event(sdev->list_wait, sdev->first_free != -1); | |
753 | } | |
754 | } | |
755 | sbio = sdev->bios[sdev->curr]; | |
756 | if (sbio->count == 0) { | |
757 | sbio->physical = physical; | |
758 | sbio->logical = logical; | |
759 | } else if (sbio->physical + sbio->count * PAGE_SIZE != physical) { | |
760 | scrub_submit(sdev); | |
761 | goto again; | |
762 | } | |
763 | sbio->spag[sbio->count].flags = flags; | |
764 | sbio->spag[sbio->count].generation = gen; | |
765 | sbio->spag[sbio->count].have_csum = 0; | |
766 | sbio->spag[sbio->count].mirror_num = mirror_num; | |
767 | if (csum) { | |
768 | sbio->spag[sbio->count].have_csum = 1; | |
769 | memcpy(sbio->spag[sbio->count].csum, csum, sdev->csum_size); | |
770 | } | |
771 | ++sbio->count; | |
772 | if (sbio->count == SCRUB_PAGES_PER_BIO || force) | |
773 | scrub_submit(sdev); | |
774 | ||
775 | return 0; | |
776 | } | |
777 | ||
778 | static int scrub_find_csum(struct scrub_dev *sdev, u64 logical, u64 len, | |
779 | u8 *csum) | |
780 | { | |
781 | struct btrfs_ordered_sum *sum = NULL; | |
782 | int ret = 0; | |
783 | unsigned long i; | |
784 | unsigned long num_sectors; | |
785 | u32 sectorsize = sdev->dev->dev_root->sectorsize; | |
786 | ||
787 | while (!list_empty(&sdev->csum_list)) { | |
788 | sum = list_first_entry(&sdev->csum_list, | |
789 | struct btrfs_ordered_sum, list); | |
790 | if (sum->bytenr > logical) | |
791 | return 0; | |
792 | if (sum->bytenr + sum->len > logical) | |
793 | break; | |
794 | ||
795 | ++sdev->stat.csum_discards; | |
796 | list_del(&sum->list); | |
797 | kfree(sum); | |
798 | sum = NULL; | |
799 | } | |
800 | if (!sum) | |
801 | return 0; | |
802 | ||
803 | num_sectors = sum->len / sectorsize; | |
804 | for (i = 0; i < num_sectors; ++i) { | |
805 | if (sum->sums[i].bytenr == logical) { | |
806 | memcpy(csum, &sum->sums[i].sum, sdev->csum_size); | |
807 | ret = 1; | |
808 | break; | |
809 | } | |
810 | } | |
811 | if (ret && i == num_sectors - 1) { | |
812 | list_del(&sum->list); | |
813 | kfree(sum); | |
814 | } | |
815 | return ret; | |
816 | } | |
817 | ||
818 | /* scrub extent tries to collect up to 64 kB for each bio */ | |
819 | static int scrub_extent(struct scrub_dev *sdev, u64 logical, u64 len, | |
820 | u64 physical, u64 flags, u64 gen, u64 mirror_num) | |
821 | { | |
822 | int ret; | |
823 | u8 csum[BTRFS_CSUM_SIZE]; | |
824 | ||
825 | while (len) { | |
826 | u64 l = min_t(u64, len, PAGE_SIZE); | |
827 | int have_csum = 0; | |
828 | ||
829 | if (flags & BTRFS_EXTENT_FLAG_DATA) { | |
830 | /* push csums to sbio */ | |
831 | have_csum = scrub_find_csum(sdev, logical, l, csum); | |
832 | if (have_csum == 0) | |
833 | ++sdev->stat.no_csum; | |
834 | } | |
835 | ret = scrub_page(sdev, logical, l, physical, flags, gen, | |
836 | mirror_num, have_csum ? csum : NULL, 0); | |
837 | if (ret) | |
838 | return ret; | |
839 | len -= l; | |
840 | logical += l; | |
841 | physical += l; | |
842 | } | |
843 | return 0; | |
844 | } | |
845 | ||
846 | static noinline_for_stack int scrub_stripe(struct scrub_dev *sdev, | |
847 | struct map_lookup *map, int num, u64 base, u64 length) | |
848 | { | |
849 | struct btrfs_path *path; | |
850 | struct btrfs_fs_info *fs_info = sdev->dev->dev_root->fs_info; | |
851 | struct btrfs_root *root = fs_info->extent_root; | |
852 | struct btrfs_root *csum_root = fs_info->csum_root; | |
853 | struct btrfs_extent_item *extent; | |
854 | u64 flags; | |
855 | int ret; | |
856 | int slot; | |
857 | int i; | |
858 | u64 nstripes; | |
859 | int start_stripe; | |
860 | struct extent_buffer *l; | |
861 | struct btrfs_key key; | |
862 | u64 physical; | |
863 | u64 logical; | |
864 | u64 generation; | |
865 | u64 mirror_num; | |
866 | ||
867 | u64 increment = map->stripe_len; | |
868 | u64 offset; | |
869 | ||
870 | nstripes = length; | |
871 | offset = 0; | |
872 | do_div(nstripes, map->stripe_len); | |
873 | if (map->type & BTRFS_BLOCK_GROUP_RAID0) { | |
874 | offset = map->stripe_len * num; | |
875 | increment = map->stripe_len * map->num_stripes; | |
876 | mirror_num = 0; | |
877 | } else if (map->type & BTRFS_BLOCK_GROUP_RAID10) { | |
878 | int factor = map->num_stripes / map->sub_stripes; | |
879 | offset = map->stripe_len * (num / map->sub_stripes); | |
880 | increment = map->stripe_len * factor; | |
881 | mirror_num = num % map->sub_stripes; | |
882 | } else if (map->type & BTRFS_BLOCK_GROUP_RAID1) { | |
883 | increment = map->stripe_len; | |
884 | mirror_num = num % map->num_stripes; | |
885 | } else if (map->type & BTRFS_BLOCK_GROUP_DUP) { | |
886 | increment = map->stripe_len; | |
887 | mirror_num = num % map->num_stripes; | |
888 | } else { | |
889 | increment = map->stripe_len; | |
890 | mirror_num = 0; | |
891 | } | |
892 | ||
893 | path = btrfs_alloc_path(); | |
894 | if (!path) | |
895 | return -ENOMEM; | |
896 | ||
897 | path->reada = 2; | |
898 | path->search_commit_root = 1; | |
899 | path->skip_locking = 1; | |
900 | ||
901 | /* | |
902 | * find all extents for each stripe and just read them to get | |
903 | * them into the page cache | |
904 | * FIXME: we can do better. build a more intelligent prefetching | |
905 | */ | |
906 | logical = base + offset; | |
907 | physical = map->stripes[num].physical; | |
908 | ret = 0; | |
909 | for (i = 0; i < nstripes; ++i) { | |
910 | key.objectid = logical; | |
911 | key.type = BTRFS_EXTENT_ITEM_KEY; | |
912 | key.offset = (u64)0; | |
913 | ||
914 | ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); | |
915 | if (ret < 0) | |
916 | goto out; | |
917 | ||
918 | l = path->nodes[0]; | |
919 | slot = path->slots[0]; | |
920 | btrfs_item_key_to_cpu(l, &key, slot); | |
921 | if (key.objectid != logical) { | |
922 | ret = btrfs_previous_item(root, path, 0, | |
923 | BTRFS_EXTENT_ITEM_KEY); | |
924 | if (ret < 0) | |
925 | goto out; | |
926 | } | |
927 | ||
928 | while (1) { | |
929 | l = path->nodes[0]; | |
930 | slot = path->slots[0]; | |
931 | if (slot >= btrfs_header_nritems(l)) { | |
932 | ret = btrfs_next_leaf(root, path); | |
933 | if (ret == 0) | |
934 | continue; | |
935 | if (ret < 0) | |
936 | goto out; | |
937 | ||
938 | break; | |
939 | } | |
940 | btrfs_item_key_to_cpu(l, &key, slot); | |
941 | ||
942 | if (key.objectid >= logical + map->stripe_len) | |
943 | break; | |
944 | ||
945 | path->slots[0]++; | |
946 | } | |
947 | btrfs_release_path(root, path); | |
948 | logical += increment; | |
949 | physical += map->stripe_len; | |
950 | cond_resched(); | |
951 | } | |
952 | ||
953 | /* | |
954 | * collect all data csums for the stripe to avoid seeking during | |
955 | * the scrub. This might currently (crc32) end up to be about 1MB | |
956 | */ | |
957 | start_stripe = 0; | |
958 | again: | |
959 | logical = base + offset + start_stripe * increment; | |
960 | for (i = start_stripe; i < nstripes; ++i) { | |
961 | ret = btrfs_lookup_csums_range(csum_root, logical, | |
962 | logical + map->stripe_len - 1, | |
963 | &sdev->csum_list, 1); | |
964 | if (ret) | |
965 | goto out; | |
966 | ||
967 | logical += increment; | |
968 | cond_resched(); | |
969 | } | |
970 | /* | |
971 | * now find all extents for each stripe and scrub them | |
972 | */ | |
973 | logical = base + offset + start_stripe * increment; | |
974 | physical = map->stripes[num].physical + start_stripe * map->stripe_len; | |
975 | ret = 0; | |
976 | for (i = start_stripe; i < nstripes; ++i) { | |
977 | /* | |
978 | * canceled? | |
979 | */ | |
980 | if (atomic_read(&fs_info->scrub_cancel_req) || | |
981 | atomic_read(&sdev->cancel_req)) { | |
982 | ret = -ECANCELED; | |
983 | goto out; | |
984 | } | |
985 | /* | |
986 | * check to see if we have to pause | |
987 | */ | |
988 | if (atomic_read(&fs_info->scrub_pause_req)) { | |
989 | /* push queued extents */ | |
990 | scrub_submit(sdev); | |
991 | wait_event(sdev->list_wait, | |
992 | atomic_read(&sdev->in_flight) == 0); | |
993 | atomic_inc(&fs_info->scrubs_paused); | |
994 | wake_up(&fs_info->scrub_pause_wait); | |
995 | mutex_lock(&fs_info->scrub_lock); | |
996 | while (atomic_read(&fs_info->scrub_pause_req)) { | |
997 | mutex_unlock(&fs_info->scrub_lock); | |
998 | wait_event(fs_info->scrub_pause_wait, | |
999 | atomic_read(&fs_info->scrub_pause_req) == 0); | |
1000 | mutex_lock(&fs_info->scrub_lock); | |
1001 | } | |
1002 | atomic_dec(&fs_info->scrubs_paused); | |
1003 | mutex_unlock(&fs_info->scrub_lock); | |
1004 | wake_up(&fs_info->scrub_pause_wait); | |
1005 | scrub_free_csums(sdev); | |
1006 | start_stripe = i; | |
1007 | goto again; | |
1008 | } | |
1009 | ||
1010 | key.objectid = logical; | |
1011 | key.type = BTRFS_EXTENT_ITEM_KEY; | |
1012 | key.offset = (u64)0; | |
1013 | ||
1014 | ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); | |
1015 | if (ret < 0) | |
1016 | goto out; | |
1017 | ||
1018 | l = path->nodes[0]; | |
1019 | slot = path->slots[0]; | |
1020 | btrfs_item_key_to_cpu(l, &key, slot); | |
1021 | if (key.objectid != logical) { | |
1022 | ret = btrfs_previous_item(root, path, 0, | |
1023 | BTRFS_EXTENT_ITEM_KEY); | |
1024 | if (ret < 0) | |
1025 | goto out; | |
1026 | } | |
1027 | ||
1028 | while (1) { | |
1029 | l = path->nodes[0]; | |
1030 | slot = path->slots[0]; | |
1031 | if (slot >= btrfs_header_nritems(l)) { | |
1032 | ret = btrfs_next_leaf(root, path); | |
1033 | if (ret == 0) | |
1034 | continue; | |
1035 | if (ret < 0) | |
1036 | goto out; | |
1037 | ||
1038 | break; | |
1039 | } | |
1040 | btrfs_item_key_to_cpu(l, &key, slot); | |
1041 | ||
1042 | if (key.objectid + key.offset <= logical) | |
1043 | goto next; | |
1044 | ||
1045 | if (key.objectid >= logical + map->stripe_len) | |
1046 | break; | |
1047 | ||
1048 | if (btrfs_key_type(&key) != BTRFS_EXTENT_ITEM_KEY) | |
1049 | goto next; | |
1050 | ||
1051 | extent = btrfs_item_ptr(l, slot, | |
1052 | struct btrfs_extent_item); | |
1053 | flags = btrfs_extent_flags(l, extent); | |
1054 | generation = btrfs_extent_generation(l, extent); | |
1055 | ||
1056 | if (key.objectid < logical && | |
1057 | (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK)) { | |
1058 | printk(KERN_ERR | |
1059 | "btrfs scrub: tree block %llu spanning " | |
1060 | "stripes, ignored. logical=%llu\n", | |
1061 | (unsigned long long)key.objectid, | |
1062 | (unsigned long long)logical); | |
1063 | goto next; | |
1064 | } | |
1065 | ||
1066 | /* | |
1067 | * trim extent to this stripe | |
1068 | */ | |
1069 | if (key.objectid < logical) { | |
1070 | key.offset -= logical - key.objectid; | |
1071 | key.objectid = logical; | |
1072 | } | |
1073 | if (key.objectid + key.offset > | |
1074 | logical + map->stripe_len) { | |
1075 | key.offset = logical + map->stripe_len - | |
1076 | key.objectid; | |
1077 | } | |
1078 | ||
1079 | ret = scrub_extent(sdev, key.objectid, key.offset, | |
1080 | key.objectid - logical + physical, | |
1081 | flags, generation, mirror_num); | |
1082 | if (ret) | |
1083 | goto out; | |
1084 | ||
1085 | next: | |
1086 | path->slots[0]++; | |
1087 | } | |
1088 | btrfs_release_path(root, path); | |
1089 | logical += increment; | |
1090 | physical += map->stripe_len; | |
1091 | spin_lock(&sdev->stat_lock); | |
1092 | sdev->stat.last_physical = physical; | |
1093 | spin_unlock(&sdev->stat_lock); | |
1094 | } | |
1095 | /* push queued extents */ | |
1096 | scrub_submit(sdev); | |
1097 | ||
1098 | out: | |
1099 | btrfs_free_path(path); | |
1100 | return ret < 0 ? ret : 0; | |
1101 | } | |
1102 | ||
1103 | static noinline_for_stack int scrub_chunk(struct scrub_dev *sdev, | |
1104 | u64 chunk_tree, u64 chunk_objectid, u64 chunk_offset, u64 length) | |
1105 | { | |
1106 | struct btrfs_mapping_tree *map_tree = | |
1107 | &sdev->dev->dev_root->fs_info->mapping_tree; | |
1108 | struct map_lookup *map; | |
1109 | struct extent_map *em; | |
1110 | int i; | |
1111 | int ret = -EINVAL; | |
1112 | ||
1113 | read_lock(&map_tree->map_tree.lock); | |
1114 | em = lookup_extent_mapping(&map_tree->map_tree, chunk_offset, 1); | |
1115 | read_unlock(&map_tree->map_tree.lock); | |
1116 | ||
1117 | if (!em) | |
1118 | return -EINVAL; | |
1119 | ||
1120 | map = (struct map_lookup *)em->bdev; | |
1121 | if (em->start != chunk_offset) | |
1122 | goto out; | |
1123 | ||
1124 | if (em->len < length) | |
1125 | goto out; | |
1126 | ||
1127 | for (i = 0; i < map->num_stripes; ++i) { | |
1128 | if (map->stripes[i].dev == sdev->dev) { | |
1129 | ret = scrub_stripe(sdev, map, i, chunk_offset, length); | |
1130 | if (ret) | |
1131 | goto out; | |
1132 | } | |
1133 | } | |
1134 | out: | |
1135 | free_extent_map(em); | |
1136 | ||
1137 | return ret; | |
1138 | } | |
1139 | ||
1140 | static noinline_for_stack | |
1141 | int scrub_enumerate_chunks(struct scrub_dev *sdev, u64 start, u64 end) | |
1142 | { | |
1143 | struct btrfs_dev_extent *dev_extent = NULL; | |
1144 | struct btrfs_path *path; | |
1145 | struct btrfs_root *root = sdev->dev->dev_root; | |
1146 | struct btrfs_fs_info *fs_info = root->fs_info; | |
1147 | u64 length; | |
1148 | u64 chunk_tree; | |
1149 | u64 chunk_objectid; | |
1150 | u64 chunk_offset; | |
1151 | int ret; | |
1152 | int slot; | |
1153 | struct extent_buffer *l; | |
1154 | struct btrfs_key key; | |
1155 | struct btrfs_key found_key; | |
1156 | struct btrfs_block_group_cache *cache; | |
1157 | ||
1158 | path = btrfs_alloc_path(); | |
1159 | if (!path) | |
1160 | return -ENOMEM; | |
1161 | ||
1162 | path->reada = 2; | |
1163 | path->search_commit_root = 1; | |
1164 | path->skip_locking = 1; | |
1165 | ||
1166 | key.objectid = sdev->dev->devid; | |
1167 | key.offset = 0ull; | |
1168 | key.type = BTRFS_DEV_EXTENT_KEY; | |
1169 | ||
1170 | ||
1171 | while (1) { | |
1172 | ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); | |
1173 | if (ret < 0) | |
1174 | goto out; | |
1175 | ret = 0; | |
1176 | ||
1177 | l = path->nodes[0]; | |
1178 | slot = path->slots[0]; | |
1179 | ||
1180 | btrfs_item_key_to_cpu(l, &found_key, slot); | |
1181 | ||
1182 | if (found_key.objectid != sdev->dev->devid) | |
1183 | break; | |
1184 | ||
1185 | if (btrfs_key_type(&key) != BTRFS_DEV_EXTENT_KEY) | |
1186 | break; | |
1187 | ||
1188 | if (found_key.offset >= end) | |
1189 | break; | |
1190 | ||
1191 | if (found_key.offset < key.offset) | |
1192 | break; | |
1193 | ||
1194 | dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent); | |
1195 | length = btrfs_dev_extent_length(l, dev_extent); | |
1196 | ||
1197 | if (found_key.offset + length <= start) { | |
1198 | key.offset = found_key.offset + length; | |
1199 | btrfs_release_path(root, path); | |
1200 | continue; | |
1201 | } | |
1202 | ||
1203 | chunk_tree = btrfs_dev_extent_chunk_tree(l, dev_extent); | |
1204 | chunk_objectid = btrfs_dev_extent_chunk_objectid(l, dev_extent); | |
1205 | chunk_offset = btrfs_dev_extent_chunk_offset(l, dev_extent); | |
1206 | ||
1207 | /* | |
1208 | * get a reference on the corresponding block group to prevent | |
1209 | * the chunk from going away while we scrub it | |
1210 | */ | |
1211 | cache = btrfs_lookup_block_group(fs_info, chunk_offset); | |
1212 | if (!cache) { | |
1213 | ret = -ENOENT; | |
1214 | goto out; | |
1215 | } | |
1216 | ret = scrub_chunk(sdev, chunk_tree, chunk_objectid, | |
1217 | chunk_offset, length); | |
1218 | btrfs_put_block_group(cache); | |
1219 | if (ret) | |
1220 | break; | |
1221 | ||
1222 | key.offset = found_key.offset + length; | |
1223 | btrfs_release_path(root, path); | |
1224 | } | |
1225 | ||
1226 | out: | |
1227 | btrfs_free_path(path); | |
1228 | return ret; | |
1229 | } | |
1230 | ||
1231 | static noinline_for_stack int scrub_supers(struct scrub_dev *sdev) | |
1232 | { | |
1233 | int i; | |
1234 | u64 bytenr; | |
1235 | u64 gen; | |
1236 | int ret; | |
1237 | struct btrfs_device *device = sdev->dev; | |
1238 | struct btrfs_root *root = device->dev_root; | |
1239 | ||
1240 | gen = root->fs_info->last_trans_committed; | |
1241 | ||
1242 | for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) { | |
1243 | bytenr = btrfs_sb_offset(i); | |
1244 | if (bytenr + BTRFS_SUPER_INFO_SIZE >= device->total_bytes) | |
1245 | break; | |
1246 | ||
1247 | ret = scrub_page(sdev, bytenr, PAGE_SIZE, bytenr, | |
1248 | BTRFS_EXTENT_FLAG_SUPER, gen, i, NULL, 1); | |
1249 | if (ret) | |
1250 | return ret; | |
1251 | } | |
1252 | wait_event(sdev->list_wait, atomic_read(&sdev->in_flight) == 0); | |
1253 | ||
1254 | return 0; | |
1255 | } | |
1256 | ||
1257 | /* | |
1258 | * get a reference count on fs_info->scrub_workers. start worker if necessary | |
1259 | */ | |
1260 | static noinline_for_stack int scrub_workers_get(struct btrfs_root *root) | |
1261 | { | |
1262 | struct btrfs_fs_info *fs_info = root->fs_info; | |
1263 | ||
1264 | mutex_lock(&fs_info->scrub_lock); | |
1265 | if (fs_info->scrub_workers_refcnt == 0) | |
1266 | btrfs_start_workers(&fs_info->scrub_workers, 1); | |
1267 | ++fs_info->scrub_workers_refcnt; | |
1268 | mutex_unlock(&fs_info->scrub_lock); | |
1269 | ||
1270 | return 0; | |
1271 | } | |
1272 | ||
1273 | static noinline_for_stack void scrub_workers_put(struct btrfs_root *root) | |
1274 | { | |
1275 | struct btrfs_fs_info *fs_info = root->fs_info; | |
1276 | ||
1277 | mutex_lock(&fs_info->scrub_lock); | |
1278 | if (--fs_info->scrub_workers_refcnt == 0) | |
1279 | btrfs_stop_workers(&fs_info->scrub_workers); | |
1280 | WARN_ON(fs_info->scrub_workers_refcnt < 0); | |
1281 | mutex_unlock(&fs_info->scrub_lock); | |
1282 | } | |
1283 | ||
1284 | ||
1285 | int btrfs_scrub_dev(struct btrfs_root *root, u64 devid, u64 start, u64 end, | |
1286 | struct btrfs_scrub_progress *progress) | |
1287 | { | |
1288 | struct scrub_dev *sdev; | |
1289 | struct btrfs_fs_info *fs_info = root->fs_info; | |
1290 | int ret; | |
1291 | struct btrfs_device *dev; | |
1292 | ||
1293 | if (root->fs_info->closing) | |
1294 | return -EINVAL; | |
1295 | ||
1296 | /* | |
1297 | * check some assumptions | |
1298 | */ | |
1299 | if (root->sectorsize != PAGE_SIZE || | |
1300 | root->sectorsize != root->leafsize || | |
1301 | root->sectorsize != root->nodesize) { | |
1302 | printk(KERN_ERR "btrfs_scrub: size assumptions fail\n"); | |
1303 | return -EINVAL; | |
1304 | } | |
1305 | ||
1306 | ret = scrub_workers_get(root); | |
1307 | if (ret) | |
1308 | return ret; | |
1309 | ||
1310 | mutex_lock(&root->fs_info->fs_devices->device_list_mutex); | |
1311 | dev = btrfs_find_device(root, devid, NULL, NULL); | |
1312 | if (!dev || dev->missing) { | |
1313 | mutex_unlock(&root->fs_info->fs_devices->device_list_mutex); | |
1314 | scrub_workers_put(root); | |
1315 | return -ENODEV; | |
1316 | } | |
1317 | mutex_lock(&fs_info->scrub_lock); | |
1318 | ||
1319 | if (!dev->in_fs_metadata) { | |
1320 | mutex_unlock(&fs_info->scrub_lock); | |
1321 | mutex_unlock(&root->fs_info->fs_devices->device_list_mutex); | |
1322 | scrub_workers_put(root); | |
1323 | return -ENODEV; | |
1324 | } | |
1325 | ||
1326 | if (dev->scrub_device) { | |
1327 | mutex_unlock(&fs_info->scrub_lock); | |
1328 | mutex_unlock(&root->fs_info->fs_devices->device_list_mutex); | |
1329 | scrub_workers_put(root); | |
1330 | return -EINPROGRESS; | |
1331 | } | |
1332 | sdev = scrub_setup_dev(dev); | |
1333 | if (IS_ERR(sdev)) { | |
1334 | mutex_unlock(&fs_info->scrub_lock); | |
1335 | mutex_unlock(&root->fs_info->fs_devices->device_list_mutex); | |
1336 | scrub_workers_put(root); | |
1337 | return PTR_ERR(sdev); | |
1338 | } | |
1339 | dev->scrub_device = sdev; | |
1340 | ||
1341 | atomic_inc(&fs_info->scrubs_running); | |
1342 | mutex_unlock(&fs_info->scrub_lock); | |
1343 | mutex_unlock(&root->fs_info->fs_devices->device_list_mutex); | |
1344 | ||
1345 | down_read(&fs_info->scrub_super_lock); | |
1346 | ret = scrub_supers(sdev); | |
1347 | up_read(&fs_info->scrub_super_lock); | |
1348 | ||
1349 | if (!ret) | |
1350 | ret = scrub_enumerate_chunks(sdev, start, end); | |
1351 | ||
1352 | wait_event(sdev->list_wait, atomic_read(&sdev->in_flight) == 0); | |
1353 | ||
1354 | atomic_dec(&fs_info->scrubs_running); | |
1355 | wake_up(&fs_info->scrub_pause_wait); | |
1356 | ||
1357 | if (progress) | |
1358 | memcpy(progress, &sdev->stat, sizeof(*progress)); | |
1359 | ||
1360 | mutex_lock(&fs_info->scrub_lock); | |
1361 | dev->scrub_device = NULL; | |
1362 | mutex_unlock(&fs_info->scrub_lock); | |
1363 | ||
1364 | scrub_free_dev(sdev); | |
1365 | scrub_workers_put(root); | |
1366 | ||
1367 | return ret; | |
1368 | } | |
1369 | ||
1370 | int btrfs_scrub_pause(struct btrfs_root *root) | |
1371 | { | |
1372 | struct btrfs_fs_info *fs_info = root->fs_info; | |
1373 | ||
1374 | mutex_lock(&fs_info->scrub_lock); | |
1375 | atomic_inc(&fs_info->scrub_pause_req); | |
1376 | while (atomic_read(&fs_info->scrubs_paused) != | |
1377 | atomic_read(&fs_info->scrubs_running)) { | |
1378 | mutex_unlock(&fs_info->scrub_lock); | |
1379 | wait_event(fs_info->scrub_pause_wait, | |
1380 | atomic_read(&fs_info->scrubs_paused) == | |
1381 | atomic_read(&fs_info->scrubs_running)); | |
1382 | mutex_lock(&fs_info->scrub_lock); | |
1383 | } | |
1384 | mutex_unlock(&fs_info->scrub_lock); | |
1385 | ||
1386 | return 0; | |
1387 | } | |
1388 | ||
1389 | int btrfs_scrub_continue(struct btrfs_root *root) | |
1390 | { | |
1391 | struct btrfs_fs_info *fs_info = root->fs_info; | |
1392 | ||
1393 | atomic_dec(&fs_info->scrub_pause_req); | |
1394 | wake_up(&fs_info->scrub_pause_wait); | |
1395 | return 0; | |
1396 | } | |
1397 | ||
1398 | int btrfs_scrub_pause_super(struct btrfs_root *root) | |
1399 | { | |
1400 | down_write(&root->fs_info->scrub_super_lock); | |
1401 | return 0; | |
1402 | } | |
1403 | ||
1404 | int btrfs_scrub_continue_super(struct btrfs_root *root) | |
1405 | { | |
1406 | up_write(&root->fs_info->scrub_super_lock); | |
1407 | return 0; | |
1408 | } | |
1409 | ||
1410 | int btrfs_scrub_cancel(struct btrfs_root *root) | |
1411 | { | |
1412 | struct btrfs_fs_info *fs_info = root->fs_info; | |
1413 | ||
1414 | mutex_lock(&fs_info->scrub_lock); | |
1415 | if (!atomic_read(&fs_info->scrubs_running)) { | |
1416 | mutex_unlock(&fs_info->scrub_lock); | |
1417 | return -ENOTCONN; | |
1418 | } | |
1419 | ||
1420 | atomic_inc(&fs_info->scrub_cancel_req); | |
1421 | while (atomic_read(&fs_info->scrubs_running)) { | |
1422 | mutex_unlock(&fs_info->scrub_lock); | |
1423 | wait_event(fs_info->scrub_pause_wait, | |
1424 | atomic_read(&fs_info->scrubs_running) == 0); | |
1425 | mutex_lock(&fs_info->scrub_lock); | |
1426 | } | |
1427 | atomic_dec(&fs_info->scrub_cancel_req); | |
1428 | mutex_unlock(&fs_info->scrub_lock); | |
1429 | ||
1430 | return 0; | |
1431 | } | |
1432 | ||
1433 | int btrfs_scrub_cancel_dev(struct btrfs_root *root, struct btrfs_device *dev) | |
1434 | { | |
1435 | struct btrfs_fs_info *fs_info = root->fs_info; | |
1436 | struct scrub_dev *sdev; | |
1437 | ||
1438 | mutex_lock(&fs_info->scrub_lock); | |
1439 | sdev = dev->scrub_device; | |
1440 | if (!sdev) { | |
1441 | mutex_unlock(&fs_info->scrub_lock); | |
1442 | return -ENOTCONN; | |
1443 | } | |
1444 | atomic_inc(&sdev->cancel_req); | |
1445 | while (dev->scrub_device) { | |
1446 | mutex_unlock(&fs_info->scrub_lock); | |
1447 | wait_event(fs_info->scrub_pause_wait, | |
1448 | dev->scrub_device == NULL); | |
1449 | mutex_lock(&fs_info->scrub_lock); | |
1450 | } | |
1451 | mutex_unlock(&fs_info->scrub_lock); | |
1452 | ||
1453 | return 0; | |
1454 | } | |
1455 | int btrfs_scrub_cancel_devid(struct btrfs_root *root, u64 devid) | |
1456 | { | |
1457 | struct btrfs_fs_info *fs_info = root->fs_info; | |
1458 | struct btrfs_device *dev; | |
1459 | int ret; | |
1460 | ||
1461 | /* | |
1462 | * we have to hold the device_list_mutex here so the device | |
1463 | * does not go away in cancel_dev. FIXME: find a better solution | |
1464 | */ | |
1465 | mutex_lock(&fs_info->fs_devices->device_list_mutex); | |
1466 | dev = btrfs_find_device(root, devid, NULL, NULL); | |
1467 | if (!dev) { | |
1468 | mutex_unlock(&fs_info->fs_devices->device_list_mutex); | |
1469 | return -ENODEV; | |
1470 | } | |
1471 | ret = btrfs_scrub_cancel_dev(root, dev); | |
1472 | mutex_unlock(&fs_info->fs_devices->device_list_mutex); | |
1473 | ||
1474 | return ret; | |
1475 | } | |
1476 | ||
1477 | int btrfs_scrub_progress(struct btrfs_root *root, u64 devid, | |
1478 | struct btrfs_scrub_progress *progress) | |
1479 | { | |
1480 | struct btrfs_device *dev; | |
1481 | struct scrub_dev *sdev = NULL; | |
1482 | ||
1483 | mutex_lock(&root->fs_info->fs_devices->device_list_mutex); | |
1484 | dev = btrfs_find_device(root, devid, NULL, NULL); | |
1485 | if (dev) | |
1486 | sdev = dev->scrub_device; | |
1487 | if (sdev) | |
1488 | memcpy(progress, &sdev->stat, sizeof(*progress)); | |
1489 | mutex_unlock(&root->fs_info->fs_devices->device_list_mutex); | |
1490 | ||
1491 | return dev ? (sdev ? 0 : -ENOTCONN) : -ENODEV; | |
1492 | } |