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18#include <linux/sched.h>
19#include <linux/bio.h>
20#include <linux/slab.h>
21#include <linux/buffer_head.h>
22#include <linux/blkdev.h>
23#include <linux/random.h>
24#include <linux/iocontext.h>
25#include <linux/capability.h>
26#include <linux/kthread.h>
27#include <linux/math64.h>
28#include <asm/div64.h>
29#include "ctree.h"
30#include "extent_map.h"
31#include "disk-io.h"
32#include "transaction.h"
33#include "print-tree.h"
34#include "volumes.h"
35#include "async-thread.h"
36#include "check-integrity.h"
37#include "rcu-string.h"
38#include "dev-replace.h"
39#include "sysfs.h"
40
41static int btrfs_dev_replace_finishing(struct btrfs_fs_info *fs_info,
42 int scrub_ret);
43static void btrfs_dev_replace_update_device_in_mapping_tree(
44 struct btrfs_fs_info *fs_info,
45 struct btrfs_device *srcdev,
46 struct btrfs_device *tgtdev);
47static int btrfs_dev_replace_find_srcdev(struct btrfs_root *root, u64 srcdevid,
48 char *srcdev_name,
49 struct btrfs_device **device);
50static u64 __btrfs_dev_replace_cancel(struct btrfs_fs_info *fs_info);
51static int btrfs_dev_replace_kthread(void *data);
52static int btrfs_dev_replace_continue_on_mount(struct btrfs_fs_info *fs_info);
53
54
55int btrfs_init_dev_replace(struct btrfs_fs_info *fs_info)
56{
57 struct btrfs_key key;
58 struct btrfs_root *dev_root = fs_info->dev_root;
59 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
60 struct extent_buffer *eb;
61 int slot;
62 int ret = 0;
63 struct btrfs_path *path = NULL;
64 int item_size;
65 struct btrfs_dev_replace_item *ptr;
66 u64 src_devid;
67
68 path = btrfs_alloc_path();
69 if (!path) {
70 ret = -ENOMEM;
71 goto out;
72 }
73
74 key.objectid = 0;
75 key.type = BTRFS_DEV_REPLACE_KEY;
76 key.offset = 0;
77 ret = btrfs_search_slot(NULL, dev_root, &key, path, 0, 0);
78 if (ret) {
79no_valid_dev_replace_entry_found:
80 ret = 0;
81 dev_replace->replace_state =
82 BTRFS_DEV_REPLACE_ITEM_STATE_NEVER_STARTED;
83 dev_replace->cont_reading_from_srcdev_mode =
84 BTRFS_DEV_REPLACE_ITEM_CONT_READING_FROM_SRCDEV_MODE_ALWAYS;
85 dev_replace->replace_state = 0;
86 dev_replace->time_started = 0;
87 dev_replace->time_stopped = 0;
88 atomic64_set(&dev_replace->num_write_errors, 0);
89 atomic64_set(&dev_replace->num_uncorrectable_read_errors, 0);
90 dev_replace->cursor_left = 0;
91 dev_replace->committed_cursor_left = 0;
92 dev_replace->cursor_left_last_write_of_item = 0;
93 dev_replace->cursor_right = 0;
94 dev_replace->srcdev = NULL;
95 dev_replace->tgtdev = NULL;
96 dev_replace->is_valid = 0;
97 dev_replace->item_needs_writeback = 0;
98 goto out;
99 }
100 slot = path->slots[0];
101 eb = path->nodes[0];
102 item_size = btrfs_item_size_nr(eb, slot);
103 ptr = btrfs_item_ptr(eb, slot, struct btrfs_dev_replace_item);
104
105 if (item_size != sizeof(struct btrfs_dev_replace_item)) {
106 btrfs_warn(fs_info,
107 "dev_replace entry found has unexpected size, ignore entry");
108 goto no_valid_dev_replace_entry_found;
109 }
110
111 src_devid = btrfs_dev_replace_src_devid(eb, ptr);
112 dev_replace->cont_reading_from_srcdev_mode =
113 btrfs_dev_replace_cont_reading_from_srcdev_mode(eb, ptr);
114 dev_replace->replace_state = btrfs_dev_replace_replace_state(eb, ptr);
115 dev_replace->time_started = btrfs_dev_replace_time_started(eb, ptr);
116 dev_replace->time_stopped =
117 btrfs_dev_replace_time_stopped(eb, ptr);
118 atomic64_set(&dev_replace->num_write_errors,
119 btrfs_dev_replace_num_write_errors(eb, ptr));
120 atomic64_set(&dev_replace->num_uncorrectable_read_errors,
121 btrfs_dev_replace_num_uncorrectable_read_errors(eb, ptr));
122 dev_replace->cursor_left = btrfs_dev_replace_cursor_left(eb, ptr);
123 dev_replace->committed_cursor_left = dev_replace->cursor_left;
124 dev_replace->cursor_left_last_write_of_item = dev_replace->cursor_left;
125 dev_replace->cursor_right = btrfs_dev_replace_cursor_right(eb, ptr);
126 dev_replace->is_valid = 1;
127
128 dev_replace->item_needs_writeback = 0;
129 switch (dev_replace->replace_state) {
130 case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED:
131 case BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED:
132 case BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED:
133 dev_replace->srcdev = NULL;
134 dev_replace->tgtdev = NULL;
135 break;
136 case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED:
137 case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED:
138 dev_replace->srcdev = btrfs_find_device(fs_info, src_devid,
139 NULL, NULL);
140 dev_replace->tgtdev = btrfs_find_device(fs_info,
141 BTRFS_DEV_REPLACE_DEVID,
142 NULL, NULL);
143
144
145
146
147 if (!dev_replace->srcdev &&
148 !btrfs_test_opt(dev_root, DEGRADED)) {
149 ret = -EIO;
150 btrfs_warn(fs_info,
151 "cannot mount because device replace operation is ongoing and");
152 btrfs_warn(fs_info,
153 "srcdev (devid %llu) is missing, need to run 'btrfs dev scan'?",
154 src_devid);
155 }
156 if (!dev_replace->tgtdev &&
157 !btrfs_test_opt(dev_root, DEGRADED)) {
158 ret = -EIO;
159 btrfs_warn(fs_info,
160 "cannot mount because device replace operation is ongoing and");
161 btrfs_warn(fs_info,
162 "tgtdev (devid %llu) is missing, need to run 'btrfs dev scan'?",
163 BTRFS_DEV_REPLACE_DEVID);
164 }
165 if (dev_replace->tgtdev) {
166 if (dev_replace->srcdev) {
167 dev_replace->tgtdev->total_bytes =
168 dev_replace->srcdev->total_bytes;
169 dev_replace->tgtdev->disk_total_bytes =
170 dev_replace->srcdev->disk_total_bytes;
171 dev_replace->tgtdev->commit_total_bytes =
172 dev_replace->srcdev->commit_total_bytes;
173 dev_replace->tgtdev->bytes_used =
174 dev_replace->srcdev->bytes_used;
175 dev_replace->tgtdev->commit_bytes_used =
176 dev_replace->srcdev->commit_bytes_used;
177 }
178 dev_replace->tgtdev->is_tgtdev_for_dev_replace = 1;
179 btrfs_init_dev_replace_tgtdev_for_resume(fs_info,
180 dev_replace->tgtdev);
181 }
182 break;
183 }
184
185out:
186 if (path)
187 btrfs_free_path(path);
188 return ret;
189}
190
191
192
193
194
195int btrfs_run_dev_replace(struct btrfs_trans_handle *trans,
196 struct btrfs_fs_info *fs_info)
197{
198 int ret;
199 struct btrfs_root *dev_root = fs_info->dev_root;
200 struct btrfs_path *path;
201 struct btrfs_key key;
202 struct extent_buffer *eb;
203 struct btrfs_dev_replace_item *ptr;
204 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
205
206 btrfs_dev_replace_lock(dev_replace);
207 if (!dev_replace->is_valid ||
208 !dev_replace->item_needs_writeback) {
209 btrfs_dev_replace_unlock(dev_replace);
210 return 0;
211 }
212 btrfs_dev_replace_unlock(dev_replace);
213
214 key.objectid = 0;
215 key.type = BTRFS_DEV_REPLACE_KEY;
216 key.offset = 0;
217
218 path = btrfs_alloc_path();
219 if (!path) {
220 ret = -ENOMEM;
221 goto out;
222 }
223 ret = btrfs_search_slot(trans, dev_root, &key, path, -1, 1);
224 if (ret < 0) {
225 btrfs_warn(fs_info, "error %d while searching for dev_replace item!",
226 ret);
227 goto out;
228 }
229
230 if (ret == 0 &&
231 btrfs_item_size_nr(path->nodes[0], path->slots[0]) < sizeof(*ptr)) {
232
233
234
235
236
237
238
239
240
241
242
243 ret = btrfs_del_item(trans, dev_root, path);
244 if (ret != 0) {
245 btrfs_warn(fs_info, "delete too small dev_replace item failed %d!",
246 ret);
247 goto out;
248 }
249 ret = 1;
250 }
251
252 if (ret == 1) {
253
254 btrfs_release_path(path);
255 ret = btrfs_insert_empty_item(trans, dev_root, path,
256 &key, sizeof(*ptr));
257 if (ret < 0) {
258 btrfs_warn(fs_info, "insert dev_replace item failed %d!",
259 ret);
260 goto out;
261 }
262 }
263
264 eb = path->nodes[0];
265 ptr = btrfs_item_ptr(eb, path->slots[0],
266 struct btrfs_dev_replace_item);
267
268 btrfs_dev_replace_lock(dev_replace);
269 if (dev_replace->srcdev)
270 btrfs_set_dev_replace_src_devid(eb, ptr,
271 dev_replace->srcdev->devid);
272 else
273 btrfs_set_dev_replace_src_devid(eb, ptr, (u64)-1);
274 btrfs_set_dev_replace_cont_reading_from_srcdev_mode(eb, ptr,
275 dev_replace->cont_reading_from_srcdev_mode);
276 btrfs_set_dev_replace_replace_state(eb, ptr,
277 dev_replace->replace_state);
278 btrfs_set_dev_replace_time_started(eb, ptr, dev_replace->time_started);
279 btrfs_set_dev_replace_time_stopped(eb, ptr, dev_replace->time_stopped);
280 btrfs_set_dev_replace_num_write_errors(eb, ptr,
281 atomic64_read(&dev_replace->num_write_errors));
282 btrfs_set_dev_replace_num_uncorrectable_read_errors(eb, ptr,
283 atomic64_read(&dev_replace->num_uncorrectable_read_errors));
284 dev_replace->cursor_left_last_write_of_item =
285 dev_replace->cursor_left;
286 btrfs_set_dev_replace_cursor_left(eb, ptr,
287 dev_replace->cursor_left_last_write_of_item);
288 btrfs_set_dev_replace_cursor_right(eb, ptr,
289 dev_replace->cursor_right);
290 dev_replace->item_needs_writeback = 0;
291 btrfs_dev_replace_unlock(dev_replace);
292
293 btrfs_mark_buffer_dirty(eb);
294
295out:
296 btrfs_free_path(path);
297
298 return ret;
299}
300
301void btrfs_after_dev_replace_commit(struct btrfs_fs_info *fs_info)
302{
303 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
304
305 dev_replace->committed_cursor_left =
306 dev_replace->cursor_left_last_write_of_item;
307}
308
309int btrfs_dev_replace_start(struct btrfs_root *root,
310 struct btrfs_ioctl_dev_replace_args *args)
311{
312 struct btrfs_trans_handle *trans;
313 struct btrfs_fs_info *fs_info = root->fs_info;
314 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
315 int ret;
316 struct btrfs_device *tgt_device = NULL;
317 struct btrfs_device *src_device = NULL;
318
319 if (btrfs_fs_incompat(fs_info, RAID56)) {
320 btrfs_warn(fs_info, "dev_replace cannot yet handle RAID5/RAID6");
321 return -EOPNOTSUPP;
322 }
323
324 switch (args->start.cont_reading_from_srcdev_mode) {
325 case BTRFS_IOCTL_DEV_REPLACE_CONT_READING_FROM_SRCDEV_MODE_ALWAYS:
326 case BTRFS_IOCTL_DEV_REPLACE_CONT_READING_FROM_SRCDEV_MODE_AVOID:
327 break;
328 default:
329 return -EINVAL;
330 }
331
332 if ((args->start.srcdevid == 0 && args->start.srcdev_name[0] == '\0') ||
333 args->start.tgtdev_name[0] == '\0')
334 return -EINVAL;
335
336
337
338
339
340 trans = btrfs_attach_transaction(root);
341 if (!IS_ERR(trans)) {
342 ret = btrfs_commit_transaction(trans, root);
343 if (ret)
344 return ret;
345 } else if (PTR_ERR(trans) != -ENOENT) {
346 return PTR_ERR(trans);
347 }
348
349
350 mutex_lock(&fs_info->volume_mutex);
351 ret = btrfs_dev_replace_find_srcdev(root, args->start.srcdevid,
352 args->start.srcdev_name,
353 &src_device);
354 if (ret) {
355 mutex_unlock(&fs_info->volume_mutex);
356 return ret;
357 }
358
359 ret = btrfs_init_dev_replace_tgtdev(root, args->start.tgtdev_name,
360 src_device, &tgt_device);
361 mutex_unlock(&fs_info->volume_mutex);
362 if (ret)
363 return ret;
364
365 btrfs_dev_replace_lock(dev_replace);
366 switch (dev_replace->replace_state) {
367 case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED:
368 case BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED:
369 case BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED:
370 break;
371 case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED:
372 case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED:
373 args->result = BTRFS_IOCTL_DEV_REPLACE_RESULT_ALREADY_STARTED;
374 goto leave;
375 }
376
377 dev_replace->cont_reading_from_srcdev_mode =
378 args->start.cont_reading_from_srcdev_mode;
379 WARN_ON(!src_device);
380 dev_replace->srcdev = src_device;
381 WARN_ON(!tgt_device);
382 dev_replace->tgtdev = tgt_device;
383
384 printk_in_rcu(KERN_INFO
385 "BTRFS: dev_replace from %s (devid %llu) to %s started\n",
386 src_device->missing ? "<missing disk>" :
387 rcu_str_deref(src_device->name),
388 src_device->devid,
389 rcu_str_deref(tgt_device->name));
390
391
392
393
394
395 dev_replace->replace_state = BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED;
396 dev_replace->time_started = get_seconds();
397 dev_replace->cursor_left = 0;
398 dev_replace->committed_cursor_left = 0;
399 dev_replace->cursor_left_last_write_of_item = 0;
400 dev_replace->cursor_right = 0;
401 dev_replace->is_valid = 1;
402 dev_replace->item_needs_writeback = 1;
403 args->result = BTRFS_IOCTL_DEV_REPLACE_RESULT_NO_ERROR;
404 btrfs_dev_replace_unlock(dev_replace);
405
406 btrfs_wait_ordered_roots(root->fs_info, -1);
407
408
409 trans = btrfs_start_transaction(root, 0);
410 if (IS_ERR(trans)) {
411 ret = PTR_ERR(trans);
412 btrfs_dev_replace_lock(dev_replace);
413 goto leave;
414 }
415
416 ret = btrfs_commit_transaction(trans, root);
417 WARN_ON(ret);
418
419
420 ret = btrfs_scrub_dev(fs_info, src_device->devid, 0,
421 btrfs_device_get_total_bytes(src_device),
422 &dev_replace->scrub_progress, 0, 1);
423
424 ret = btrfs_dev_replace_finishing(root->fs_info, ret);
425 WARN_ON(ret);
426
427 return 0;
428
429leave:
430 dev_replace->srcdev = NULL;
431 dev_replace->tgtdev = NULL;
432 btrfs_dev_replace_unlock(dev_replace);
433 btrfs_destroy_dev_replace_tgtdev(fs_info, tgt_device);
434 return ret;
435}
436
437
438
439
440static void btrfs_rm_dev_replace_blocked(struct btrfs_fs_info *fs_info)
441{
442 s64 writers;
443 DEFINE_WAIT(wait);
444
445 set_bit(BTRFS_FS_STATE_DEV_REPLACING, &fs_info->fs_state);
446 do {
447 prepare_to_wait(&fs_info->replace_wait, &wait,
448 TASK_UNINTERRUPTIBLE);
449 writers = percpu_counter_sum(&fs_info->bio_counter);
450 if (writers)
451 schedule();
452 finish_wait(&fs_info->replace_wait, &wait);
453 } while (writers);
454}
455
456
457
458
459static void btrfs_rm_dev_replace_unblocked(struct btrfs_fs_info *fs_info)
460{
461 clear_bit(BTRFS_FS_STATE_DEV_REPLACING, &fs_info->fs_state);
462 if (waitqueue_active(&fs_info->replace_wait))
463 wake_up(&fs_info->replace_wait);
464}
465
466static int btrfs_dev_replace_finishing(struct btrfs_fs_info *fs_info,
467 int scrub_ret)
468{
469 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
470 struct btrfs_device *tgt_device;
471 struct btrfs_device *src_device;
472 struct btrfs_root *root = fs_info->tree_root;
473 u8 uuid_tmp[BTRFS_UUID_SIZE];
474 struct btrfs_trans_handle *trans;
475 int ret = 0;
476
477
478 mutex_lock(&dev_replace->lock_finishing_cancel_unmount);
479
480 btrfs_dev_replace_lock(dev_replace);
481
482 if (dev_replace->replace_state !=
483 BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED) {
484 btrfs_dev_replace_unlock(dev_replace);
485 mutex_unlock(&dev_replace->lock_finishing_cancel_unmount);
486 return 0;
487 }
488
489 tgt_device = dev_replace->tgtdev;
490 src_device = dev_replace->srcdev;
491 btrfs_dev_replace_unlock(dev_replace);
492
493
494
495
496
497 ret = btrfs_start_delalloc_roots(root->fs_info, 0, -1);
498 if (ret) {
499 mutex_unlock(&dev_replace->lock_finishing_cancel_unmount);
500 return ret;
501 }
502 btrfs_wait_ordered_roots(root->fs_info, -1);
503
504 trans = btrfs_start_transaction(root, 0);
505 if (IS_ERR(trans)) {
506 mutex_unlock(&dev_replace->lock_finishing_cancel_unmount);
507 return PTR_ERR(trans);
508 }
509 ret = btrfs_commit_transaction(trans, root);
510 WARN_ON(ret);
511
512 mutex_lock(&uuid_mutex);
513
514 mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
515 mutex_lock(&root->fs_info->chunk_mutex);
516 btrfs_dev_replace_lock(dev_replace);
517 dev_replace->replace_state =
518 scrub_ret ? BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED
519 : BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED;
520 dev_replace->tgtdev = NULL;
521 dev_replace->srcdev = NULL;
522 dev_replace->time_stopped = get_seconds();
523 dev_replace->item_needs_writeback = 1;
524
525
526 if (!scrub_ret) {
527 btrfs_dev_replace_update_device_in_mapping_tree(fs_info,
528 src_device,
529 tgt_device);
530 } else {
531 printk_in_rcu(KERN_ERR
532 "BTRFS: btrfs_scrub_dev(%s, %llu, %s) failed %d\n",
533 src_device->missing ? "<missing disk>" :
534 rcu_str_deref(src_device->name),
535 src_device->devid,
536 rcu_str_deref(tgt_device->name), scrub_ret);
537 btrfs_dev_replace_unlock(dev_replace);
538 mutex_unlock(&root->fs_info->chunk_mutex);
539 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
540 mutex_unlock(&uuid_mutex);
541 if (tgt_device)
542 btrfs_destroy_dev_replace_tgtdev(fs_info, tgt_device);
543 mutex_unlock(&dev_replace->lock_finishing_cancel_unmount);
544
545 return 0;
546 }
547
548 printk_in_rcu(KERN_INFO
549 "BTRFS: dev_replace from %s (devid %llu) to %s finished\n",
550 src_device->missing ? "<missing disk>" :
551 rcu_str_deref(src_device->name),
552 src_device->devid,
553 rcu_str_deref(tgt_device->name));
554 tgt_device->is_tgtdev_for_dev_replace = 0;
555 tgt_device->devid = src_device->devid;
556 src_device->devid = BTRFS_DEV_REPLACE_DEVID;
557 memcpy(uuid_tmp, tgt_device->uuid, sizeof(uuid_tmp));
558 memcpy(tgt_device->uuid, src_device->uuid, sizeof(tgt_device->uuid));
559 memcpy(src_device->uuid, uuid_tmp, sizeof(src_device->uuid));
560 btrfs_device_set_total_bytes(tgt_device, src_device->total_bytes);
561 btrfs_device_set_disk_total_bytes(tgt_device,
562 src_device->disk_total_bytes);
563 btrfs_device_set_bytes_used(tgt_device, src_device->bytes_used);
564 ASSERT(list_empty(&src_device->resized_list));
565 tgt_device->commit_total_bytes = src_device->commit_total_bytes;
566 tgt_device->commit_bytes_used = src_device->bytes_used;
567 if (fs_info->sb->s_bdev == src_device->bdev)
568 fs_info->sb->s_bdev = tgt_device->bdev;
569 if (fs_info->fs_devices->latest_bdev == src_device->bdev)
570 fs_info->fs_devices->latest_bdev = tgt_device->bdev;
571 list_add(&tgt_device->dev_alloc_list, &fs_info->fs_devices->alloc_list);
572 fs_info->fs_devices->rw_devices++;
573
574
575 btrfs_kobj_rm_device(fs_info, src_device);
576 btrfs_kobj_add_device(fs_info, tgt_device);
577
578 btrfs_dev_replace_unlock(dev_replace);
579
580 btrfs_rm_dev_replace_blocked(fs_info);
581
582 btrfs_rm_dev_replace_srcdev(fs_info, src_device);
583
584 btrfs_rm_dev_replace_unblocked(fs_info);
585
586
587
588
589
590
591
592
593 mutex_unlock(&root->fs_info->chunk_mutex);
594 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
595 mutex_unlock(&uuid_mutex);
596
597
598 trans = btrfs_start_transaction(root, 0);
599 if (!IS_ERR(trans))
600 btrfs_commit_transaction(trans, root);
601
602 mutex_unlock(&dev_replace->lock_finishing_cancel_unmount);
603
604 return 0;
605}
606
607static void btrfs_dev_replace_update_device_in_mapping_tree(
608 struct btrfs_fs_info *fs_info,
609 struct btrfs_device *srcdev,
610 struct btrfs_device *tgtdev)
611{
612 struct extent_map_tree *em_tree = &fs_info->mapping_tree.map_tree;
613 struct extent_map *em;
614 struct map_lookup *map;
615 u64 start = 0;
616 int i;
617
618 write_lock(&em_tree->lock);
619 do {
620 em = lookup_extent_mapping(em_tree, start, (u64)-1);
621 if (!em)
622 break;
623 map = (struct map_lookup *)em->bdev;
624 for (i = 0; i < map->num_stripes; i++)
625 if (srcdev == map->stripes[i].dev)
626 map->stripes[i].dev = tgtdev;
627 start = em->start + em->len;
628 free_extent_map(em);
629 } while (start);
630 write_unlock(&em_tree->lock);
631}
632
633static int btrfs_dev_replace_find_srcdev(struct btrfs_root *root, u64 srcdevid,
634 char *srcdev_name,
635 struct btrfs_device **device)
636{
637 int ret;
638
639 if (srcdevid) {
640 ret = 0;
641 *device = btrfs_find_device(root->fs_info, srcdevid, NULL,
642 NULL);
643 if (!*device)
644 ret = -ENOENT;
645 } else {
646 ret = btrfs_find_device_missing_or_by_path(root, srcdev_name,
647 device);
648 }
649 return ret;
650}
651
652void btrfs_dev_replace_status(struct btrfs_fs_info *fs_info,
653 struct btrfs_ioctl_dev_replace_args *args)
654{
655 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
656 struct btrfs_device *srcdev;
657
658 btrfs_dev_replace_lock(dev_replace);
659
660
661 args->result = BTRFS_IOCTL_DEV_REPLACE_RESULT_NO_ERROR;
662 args->status.replace_state = dev_replace->replace_state;
663 args->status.time_started = dev_replace->time_started;
664 args->status.time_stopped = dev_replace->time_stopped;
665 args->status.num_write_errors =
666 atomic64_read(&dev_replace->num_write_errors);
667 args->status.num_uncorrectable_read_errors =
668 atomic64_read(&dev_replace->num_uncorrectable_read_errors);
669 switch (dev_replace->replace_state) {
670 case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED:
671 case BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED:
672 args->status.progress_1000 = 0;
673 break;
674 case BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED:
675 args->status.progress_1000 = 1000;
676 break;
677 case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED:
678 case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED:
679 srcdev = dev_replace->srcdev;
680 args->status.progress_1000 = div64_u64(dev_replace->cursor_left,
681 div64_u64(btrfs_device_get_total_bytes(srcdev), 1000));
682 break;
683 }
684 btrfs_dev_replace_unlock(dev_replace);
685}
686
687int btrfs_dev_replace_cancel(struct btrfs_fs_info *fs_info,
688 struct btrfs_ioctl_dev_replace_args *args)
689{
690 args->result = __btrfs_dev_replace_cancel(fs_info);
691 return 0;
692}
693
694static u64 __btrfs_dev_replace_cancel(struct btrfs_fs_info *fs_info)
695{
696 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
697 struct btrfs_device *tgt_device = NULL;
698 struct btrfs_trans_handle *trans;
699 struct btrfs_root *root = fs_info->tree_root;
700 u64 result;
701 int ret;
702
703 if (fs_info->sb->s_flags & MS_RDONLY)
704 return -EROFS;
705
706 mutex_lock(&dev_replace->lock_finishing_cancel_unmount);
707 btrfs_dev_replace_lock(dev_replace);
708 switch (dev_replace->replace_state) {
709 case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED:
710 case BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED:
711 case BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED:
712 result = BTRFS_IOCTL_DEV_REPLACE_RESULT_NOT_STARTED;
713 btrfs_dev_replace_unlock(dev_replace);
714 goto leave;
715 case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED:
716 case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED:
717 result = BTRFS_IOCTL_DEV_REPLACE_RESULT_NO_ERROR;
718 tgt_device = dev_replace->tgtdev;
719 dev_replace->tgtdev = NULL;
720 dev_replace->srcdev = NULL;
721 break;
722 }
723 dev_replace->replace_state = BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED;
724 dev_replace->time_stopped = get_seconds();
725 dev_replace->item_needs_writeback = 1;
726 btrfs_dev_replace_unlock(dev_replace);
727 btrfs_scrub_cancel(fs_info);
728
729 trans = btrfs_start_transaction(root, 0);
730 if (IS_ERR(trans)) {
731 mutex_unlock(&dev_replace->lock_finishing_cancel_unmount);
732 return PTR_ERR(trans);
733 }
734 ret = btrfs_commit_transaction(trans, root);
735 WARN_ON(ret);
736 if (tgt_device)
737 btrfs_destroy_dev_replace_tgtdev(fs_info, tgt_device);
738
739leave:
740 mutex_unlock(&dev_replace->lock_finishing_cancel_unmount);
741 return result;
742}
743
744void btrfs_dev_replace_suspend_for_unmount(struct btrfs_fs_info *fs_info)
745{
746 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
747
748 mutex_lock(&dev_replace->lock_finishing_cancel_unmount);
749 btrfs_dev_replace_lock(dev_replace);
750 switch (dev_replace->replace_state) {
751 case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED:
752 case BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED:
753 case BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED:
754 case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED:
755 break;
756 case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED:
757 dev_replace->replace_state =
758 BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED;
759 dev_replace->time_stopped = get_seconds();
760 dev_replace->item_needs_writeback = 1;
761 btrfs_info(fs_info, "suspending dev_replace for unmount");
762 break;
763 }
764
765 btrfs_dev_replace_unlock(dev_replace);
766 mutex_unlock(&dev_replace->lock_finishing_cancel_unmount);
767}
768
769
770int btrfs_resume_dev_replace_async(struct btrfs_fs_info *fs_info)
771{
772 struct task_struct *task;
773 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
774
775 btrfs_dev_replace_lock(dev_replace);
776 switch (dev_replace->replace_state) {
777 case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED:
778 case BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED:
779 case BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED:
780 btrfs_dev_replace_unlock(dev_replace);
781 return 0;
782 case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED:
783 break;
784 case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED:
785 dev_replace->replace_state =
786 BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED;
787 break;
788 }
789 if (!dev_replace->tgtdev || !dev_replace->tgtdev->bdev) {
790 btrfs_info(fs_info, "cannot continue dev_replace, tgtdev is missing");
791 btrfs_info(fs_info,
792 "you may cancel the operation after 'mount -o degraded'");
793 btrfs_dev_replace_unlock(dev_replace);
794 return 0;
795 }
796 btrfs_dev_replace_unlock(dev_replace);
797
798 WARN_ON(atomic_xchg(
799 &fs_info->mutually_exclusive_operation_running, 1));
800 task = kthread_run(btrfs_dev_replace_kthread, fs_info, "btrfs-devrepl");
801 return PTR_ERR_OR_ZERO(task);
802}
803
804static int btrfs_dev_replace_kthread(void *data)
805{
806 struct btrfs_fs_info *fs_info = data;
807 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
808 struct btrfs_ioctl_dev_replace_args *status_args;
809 u64 progress;
810
811 status_args = kzalloc(sizeof(*status_args), GFP_NOFS);
812 if (status_args) {
813 btrfs_dev_replace_status(fs_info, status_args);
814 progress = status_args->status.progress_1000;
815 kfree(status_args);
816 do_div(progress, 10);
817 printk_in_rcu(KERN_INFO
818 "BTRFS: continuing dev_replace from %s (devid %llu) to %s @%u%%\n",
819 dev_replace->srcdev->missing ? "<missing disk>" :
820 rcu_str_deref(dev_replace->srcdev->name),
821 dev_replace->srcdev->devid,
822 dev_replace->tgtdev ?
823 rcu_str_deref(dev_replace->tgtdev->name) :
824 "<missing target disk>",
825 (unsigned int)progress);
826 }
827 btrfs_dev_replace_continue_on_mount(fs_info);
828 atomic_set(&fs_info->mutually_exclusive_operation_running, 0);
829
830 return 0;
831}
832
833static int btrfs_dev_replace_continue_on_mount(struct btrfs_fs_info *fs_info)
834{
835 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
836 int ret;
837
838 ret = btrfs_scrub_dev(fs_info, dev_replace->srcdev->devid,
839 dev_replace->committed_cursor_left,
840 btrfs_device_get_total_bytes(dev_replace->srcdev),
841 &dev_replace->scrub_progress, 0, 1);
842 ret = btrfs_dev_replace_finishing(fs_info, ret);
843 WARN_ON(ret);
844 return 0;
845}
846
847int btrfs_dev_replace_is_ongoing(struct btrfs_dev_replace *dev_replace)
848{
849 if (!dev_replace->is_valid)
850 return 0;
851
852 switch (dev_replace->replace_state) {
853 case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED:
854 case BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED:
855 case BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED:
856 return 0;
857 case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED:
858 case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED:
859
860
861
862
863
864
865
866
867
868
869 break;
870 }
871 return 1;
872}
873
874void btrfs_dev_replace_lock(struct btrfs_dev_replace *dev_replace)
875{
876
877 if (atomic_read(&dev_replace->nesting_level) == 0) {
878acquire_lock:
879
880
881 mutex_lock(&dev_replace->lock);
882 mutex_lock(&dev_replace->lock_management_lock);
883 dev_replace->lock_owner = current->pid;
884 atomic_inc(&dev_replace->nesting_level);
885 mutex_unlock(&dev_replace->lock_management_lock);
886 return;
887 }
888
889 mutex_lock(&dev_replace->lock_management_lock);
890 if (atomic_read(&dev_replace->nesting_level) > 0 &&
891 dev_replace->lock_owner == current->pid) {
892 WARN_ON(!mutex_is_locked(&dev_replace->lock));
893 atomic_inc(&dev_replace->nesting_level);
894 mutex_unlock(&dev_replace->lock_management_lock);
895 return;
896 }
897
898 mutex_unlock(&dev_replace->lock_management_lock);
899 goto acquire_lock;
900}
901
902void btrfs_dev_replace_unlock(struct btrfs_dev_replace *dev_replace)
903{
904 WARN_ON(!mutex_is_locked(&dev_replace->lock));
905 mutex_lock(&dev_replace->lock_management_lock);
906 WARN_ON(atomic_read(&dev_replace->nesting_level) < 1);
907 WARN_ON(dev_replace->lock_owner != current->pid);
908 atomic_dec(&dev_replace->nesting_level);
909 if (atomic_read(&dev_replace->nesting_level) == 0) {
910 dev_replace->lock_owner = 0;
911 mutex_unlock(&dev_replace->lock_management_lock);
912 mutex_unlock(&dev_replace->lock);
913 } else {
914 mutex_unlock(&dev_replace->lock_management_lock);
915 }
916}
917
918void btrfs_bio_counter_inc_noblocked(struct btrfs_fs_info *fs_info)
919{
920 percpu_counter_inc(&fs_info->bio_counter);
921}
922
923void btrfs_bio_counter_dec(struct btrfs_fs_info *fs_info)
924{
925 percpu_counter_dec(&fs_info->bio_counter);
926
927 if (waitqueue_active(&fs_info->replace_wait))
928 wake_up(&fs_info->replace_wait);
929}
930
931void btrfs_bio_counter_inc_blocked(struct btrfs_fs_info *fs_info)
932{
933 DEFINE_WAIT(wait);
934again:
935 percpu_counter_inc(&fs_info->bio_counter);
936 if (test_bit(BTRFS_FS_STATE_DEV_REPLACING, &fs_info->fs_state)) {
937 btrfs_bio_counter_dec(fs_info);
938 wait_event(fs_info->replace_wait,
939 !test_bit(BTRFS_FS_STATE_DEV_REPLACING,
940 &fs_info->fs_state));
941 goto again;
942 }
943
944}
945
