blob: 5ec03d999c37bfb3e48d937abd79b6dc57cd5257 [file] [log] [blame]
Stefan Behrense93c89c2012-11-05 17:33:06 +01001/*
2 * Copyright (C) STRATO AG 2012. 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#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>
Stefan Behrense93c89c2012-11-05 17:33:06 +010029#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"
Anand Jain49c6f732014-06-03 11:36:02 +080039#include "sysfs.h"
Stefan Behrense93c89c2012-11-05 17:33:06 +010040
Stefan Behrense93c89c2012-11-05 17:33:06 +010041static 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)) {
Frank Holtonefe120a2013-12-20 11:37:06 -0500106 btrfs_warn(fs_info,
107 "dev_replace entry found has unexpected size, ignore entry");
Stefan Behrense93c89c2012-11-05 17:33:06 +0100108 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 * allow 'btrfs dev replace_cancel' if src/tgt device is
145 * missing
146 */
147 if (!dev_replace->srcdev &&
148 !btrfs_test_opt(dev_root, DEGRADED)) {
149 ret = -EIO;
Frank Holtonefe120a2013-12-20 11:37:06 -0500150 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);
Stefan Behrense93c89c2012-11-05 17:33:06 +0100155 }
156 if (!dev_replace->tgtdev &&
157 !btrfs_test_opt(dev_root, DEGRADED)) {
158 ret = -EIO;
Frank Holtonefe120a2013-12-20 11:37:06 -0500159 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'?",
Geert Uytterhoeven6e71c472013-08-20 13:20:08 +0200163 BTRFS_DEV_REPLACE_DEVID);
Stefan Behrense93c89c2012-11-05 17:33:06 +0100164 }
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;
Miao Xie935e5cc2014-09-03 21:35:33 +0800171 dev_replace->tgtdev->commit_total_bytes =
172 dev_replace->srcdev->commit_total_bytes;
Stefan Behrense93c89c2012-11-05 17:33:06 +0100173 dev_replace->tgtdev->bytes_used =
174 dev_replace->srcdev->bytes_used;
Miao Xiece7213c2014-09-03 21:35:34 +0800175 dev_replace->tgtdev->commit_bytes_used =
176 dev_replace->srcdev->commit_bytes_used;
Stefan Behrense93c89c2012-11-05 17:33:06 +0100177 }
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 * called from commit_transaction. Writes changed device replace state to
193 * disk.
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) {
Frank Holtonefe120a2013-12-20 11:37:06 -0500225 btrfs_warn(fs_info, "error %d while searching for dev_replace item!",
Stefan Behrense93c89c2012-11-05 17:33:06 +0100226 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 * need to delete old one and insert a new one.
234 * Since no attempt is made to recover any old state, if the
235 * dev_replace state is 'running', the data on the target
236 * drive is lost.
237 * It would be possible to recover the state: just make sure
238 * that the beginning of the item is never changed and always
239 * contains all the essential information. Then read this
240 * minimal set of information and use it as a base for the
241 * new state.
242 */
243 ret = btrfs_del_item(trans, dev_root, path);
244 if (ret != 0) {
Frank Holtonefe120a2013-12-20 11:37:06 -0500245 btrfs_warn(fs_info, "delete too small dev_replace item failed %d!",
Stefan Behrense93c89c2012-11-05 17:33:06 +0100246 ret);
247 goto out;
248 }
249 ret = 1;
250 }
251
252 if (ret == 1) {
253 /* need to insert a new item */
254 btrfs_release_path(path);
255 ret = btrfs_insert_empty_item(trans, dev_root, path,
256 &key, sizeof(*ptr));
257 if (ret < 0) {
Frank Holtonefe120a2013-12-20 11:37:06 -0500258 btrfs_warn(fs_info, "insert dev_replace item failed %d!",
Stefan Behrense93c89c2012-11-05 17:33:06 +0100259 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
Stefan Behrense93c89c2012-11-05 17:33:06 +0100309int 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 switch (args->start.cont_reading_from_srcdev_mode) {
320 case BTRFS_IOCTL_DEV_REPLACE_CONT_READING_FROM_SRCDEV_MODE_ALWAYS:
321 case BTRFS_IOCTL_DEV_REPLACE_CONT_READING_FROM_SRCDEV_MODE_AVOID:
322 break;
323 default:
324 return -EINVAL;
325 }
326
327 if ((args->start.srcdevid == 0 && args->start.srcdev_name[0] == '\0') ||
328 args->start.tgtdev_name[0] == '\0')
329 return -EINVAL;
330
Miao Xie935e5cc2014-09-03 21:35:33 +0800331 /*
332 * Here we commit the transaction to make sure commit_total_bytes
333 * of all the devices are updated.
334 */
335 trans = btrfs_attach_transaction(root);
336 if (!IS_ERR(trans)) {
337 ret = btrfs_commit_transaction(trans, root);
338 if (ret)
339 return ret;
340 } else if (PTR_ERR(trans) != -ENOENT) {
341 return PTR_ERR(trans);
342 }
343
344 /* the disk copy procedure reuses the scrub code */
Stefan Behrense93c89c2012-11-05 17:33:06 +0100345 mutex_lock(&fs_info->volume_mutex);
Stefan Behrense93c89c2012-11-05 17:33:06 +0100346 ret = btrfs_dev_replace_find_srcdev(root, args->start.srcdevid,
347 args->start.srcdev_name,
348 &src_device);
Stefan Behrense93c89c2012-11-05 17:33:06 +0100349 if (ret) {
Miao Xie1c433662014-09-03 21:35:32 +0800350 mutex_unlock(&fs_info->volume_mutex);
351 return ret;
Stefan Behrense93c89c2012-11-05 17:33:06 +0100352 }
353
Miao Xie1c433662014-09-03 21:35:32 +0800354 ret = btrfs_init_dev_replace_tgtdev(root, args->start.tgtdev_name,
355 src_device, &tgt_device);
356 mutex_unlock(&fs_info->volume_mutex);
357 if (ret)
358 return ret;
Stefan Behrense93c89c2012-11-05 17:33:06 +0100359
360 btrfs_dev_replace_lock(dev_replace);
361 switch (dev_replace->replace_state) {
362 case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED:
363 case BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED:
364 case BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED:
365 break;
366 case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED:
367 case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED:
368 args->result = BTRFS_IOCTL_DEV_REPLACE_RESULT_ALREADY_STARTED;
369 goto leave;
370 }
371
372 dev_replace->cont_reading_from_srcdev_mode =
373 args->start.cont_reading_from_srcdev_mode;
374 WARN_ON(!src_device);
375 dev_replace->srcdev = src_device;
376 WARN_ON(!tgt_device);
377 dev_replace->tgtdev = tgt_device;
378
379 printk_in_rcu(KERN_INFO
Frank Holtonefe120a2013-12-20 11:37:06 -0500380 "BTRFS: dev_replace from %s (devid %llu) to %s started\n",
Stefan Behrense93c89c2012-11-05 17:33:06 +0100381 src_device->missing ? "<missing disk>" :
382 rcu_str_deref(src_device->name),
383 src_device->devid,
384 rcu_str_deref(tgt_device->name));
385
Stefan Behrense93c89c2012-11-05 17:33:06 +0100386 /*
387 * from now on, the writes to the srcdev are all duplicated to
388 * go to the tgtdev as well (refer to btrfs_map_block()).
389 */
390 dev_replace->replace_state = BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED;
Zach Brown4546bca2013-10-16 12:10:32 -0700391 dev_replace->time_started = get_seconds();
Stefan Behrense93c89c2012-11-05 17:33:06 +0100392 dev_replace->cursor_left = 0;
393 dev_replace->committed_cursor_left = 0;
394 dev_replace->cursor_left_last_write_of_item = 0;
395 dev_replace->cursor_right = 0;
396 dev_replace->is_valid = 1;
397 dev_replace->item_needs_writeback = 1;
398 args->result = BTRFS_IOCTL_DEV_REPLACE_RESULT_NO_ERROR;
399 btrfs_dev_replace_unlock(dev_replace);
400
Miao Xieb0244192013-11-04 23:13:25 +0800401 btrfs_wait_ordered_roots(root->fs_info, -1);
Stefan Behrense93c89c2012-11-05 17:33:06 +0100402
403 /* force writing the updated state information to disk */
404 trans = btrfs_start_transaction(root, 0);
405 if (IS_ERR(trans)) {
406 ret = PTR_ERR(trans);
407 btrfs_dev_replace_lock(dev_replace);
408 goto leave;
409 }
410
411 ret = btrfs_commit_transaction(trans, root);
412 WARN_ON(ret);
413
414 /* the disk copy procedure reuses the scrub code */
415 ret = btrfs_scrub_dev(fs_info, src_device->devid, 0,
Miao Xie7cc8e582014-09-03 21:35:38 +0800416 btrfs_device_get_total_bytes(src_device),
Stefan Behrense93c89c2012-11-05 17:33:06 +0100417 &dev_replace->scrub_progress, 0, 1);
418
419 ret = btrfs_dev_replace_finishing(root->fs_info, ret);
Eryu Guan2fc9f6b2014-10-13 12:42:12 +0800420 /* don't warn if EINPROGRESS, someone else might be running scrub */
421 if (ret == -EINPROGRESS) {
422 args->result = BTRFS_IOCTL_DEV_REPLACE_RESULT_SCRUB_INPROGRESS;
423 ret = 0;
424 } else {
425 WARN_ON(ret);
426 }
Stefan Behrense93c89c2012-11-05 17:33:06 +0100427
Eryu Guan2fc9f6b2014-10-13 12:42:12 +0800428 return ret;
Stefan Behrense93c89c2012-11-05 17:33:06 +0100429
430leave:
431 dev_replace->srcdev = NULL;
432 dev_replace->tgtdev = NULL;
433 btrfs_dev_replace_unlock(dev_replace);
Miao Xie1c433662014-09-03 21:35:32 +0800434 btrfs_destroy_dev_replace_tgtdev(fs_info, tgt_device);
Stefan Behrense93c89c2012-11-05 17:33:06 +0100435 return ret;
436}
437
Miao Xiec404e0d2014-01-30 16:46:55 +0800438/*
439 * blocked until all flighting bios are finished.
440 */
441static void btrfs_rm_dev_replace_blocked(struct btrfs_fs_info *fs_info)
442{
Miao Xiec404e0d2014-01-30 16:46:55 +0800443 set_bit(BTRFS_FS_STATE_DEV_REPLACING, &fs_info->fs_state);
Zhao Lei76539472015-01-20 15:11:38 +0800444 wait_event(fs_info->replace_wait, !percpu_counter_sum(
445 &fs_info->bio_counter));
Miao Xiec404e0d2014-01-30 16:46:55 +0800446}
447
448/*
449 * we have removed target device, it is safe to allow new bios request.
450 */
451static void btrfs_rm_dev_replace_unblocked(struct btrfs_fs_info *fs_info)
452{
453 clear_bit(BTRFS_FS_STATE_DEV_REPLACING, &fs_info->fs_state);
454 if (waitqueue_active(&fs_info->replace_wait))
455 wake_up(&fs_info->replace_wait);
456}
457
Stefan Behrense93c89c2012-11-05 17:33:06 +0100458static int btrfs_dev_replace_finishing(struct btrfs_fs_info *fs_info,
459 int scrub_ret)
460{
461 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
462 struct btrfs_device *tgt_device;
463 struct btrfs_device *src_device;
464 struct btrfs_root *root = fs_info->tree_root;
465 u8 uuid_tmp[BTRFS_UUID_SIZE];
466 struct btrfs_trans_handle *trans;
467 int ret = 0;
468
469 /* don't allow cancel or unmount to disturb the finishing procedure */
470 mutex_lock(&dev_replace->lock_finishing_cancel_unmount);
471
472 btrfs_dev_replace_lock(dev_replace);
473 /* was the operation canceled, or is it finished? */
474 if (dev_replace->replace_state !=
475 BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED) {
476 btrfs_dev_replace_unlock(dev_replace);
477 mutex_unlock(&dev_replace->lock_finishing_cancel_unmount);
478 return 0;
479 }
480
481 tgt_device = dev_replace->tgtdev;
482 src_device = dev_replace->srcdev;
483 btrfs_dev_replace_unlock(dev_replace);
484
Stefan Behrense93c89c2012-11-05 17:33:06 +0100485 /*
486 * flush all outstanding I/O and inode extent mappings before the
487 * copy operation is declared as being finished
488 */
Miao Xie6c255e62014-03-06 13:55:01 +0800489 ret = btrfs_start_delalloc_roots(root->fs_info, 0, -1);
Miao Xie3edb2a62013-01-22 10:49:33 +0000490 if (ret) {
491 mutex_unlock(&dev_replace->lock_finishing_cancel_unmount);
492 return ret;
493 }
Miao Xieb0244192013-11-04 23:13:25 +0800494 btrfs_wait_ordered_roots(root->fs_info, -1);
Stefan Behrense93c89c2012-11-05 17:33:06 +0100495
496 trans = btrfs_start_transaction(root, 0);
497 if (IS_ERR(trans)) {
498 mutex_unlock(&dev_replace->lock_finishing_cancel_unmount);
499 return PTR_ERR(trans);
500 }
501 ret = btrfs_commit_transaction(trans, root);
502 WARN_ON(ret);
503
Miao Xie67a2c452014-09-03 21:35:43 +0800504 mutex_lock(&uuid_mutex);
Stefan Behrense93c89c2012-11-05 17:33:06 +0100505 /* keep away write_all_supers() during the finishing procedure */
506 mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
Miao Xie2196d6e2014-09-03 21:35:41 +0800507 mutex_lock(&root->fs_info->chunk_mutex);
Stefan Behrense93c89c2012-11-05 17:33:06 +0100508 btrfs_dev_replace_lock(dev_replace);
509 dev_replace->replace_state =
510 scrub_ret ? BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED
511 : BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED;
512 dev_replace->tgtdev = NULL;
513 dev_replace->srcdev = NULL;
Zach Brown4546bca2013-10-16 12:10:32 -0700514 dev_replace->time_stopped = get_seconds();
Stefan Behrense93c89c2012-11-05 17:33:06 +0100515 dev_replace->item_needs_writeback = 1;
516
Miao Xiec404e0d2014-01-30 16:46:55 +0800517 /* replace old device with new one in mapping tree */
518 if (!scrub_ret) {
519 btrfs_dev_replace_update_device_in_mapping_tree(fs_info,
520 src_device,
521 tgt_device);
522 } else {
Stefan Behrense93c89c2012-11-05 17:33:06 +0100523 printk_in_rcu(KERN_ERR
Frank Holtonefe120a2013-12-20 11:37:06 -0500524 "BTRFS: btrfs_scrub_dev(%s, %llu, %s) failed %d\n",
Stefan Behrense93c89c2012-11-05 17:33:06 +0100525 src_device->missing ? "<missing disk>" :
526 rcu_str_deref(src_device->name),
527 src_device->devid,
528 rcu_str_deref(tgt_device->name), scrub_ret);
529 btrfs_dev_replace_unlock(dev_replace);
Miao Xie391cd9d2014-01-30 16:46:54 +0800530 mutex_unlock(&root->fs_info->chunk_mutex);
Miao Xie2196d6e2014-09-03 21:35:41 +0800531 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
Miao Xie67a2c452014-09-03 21:35:43 +0800532 mutex_unlock(&uuid_mutex);
Stefan Behrense93c89c2012-11-05 17:33:06 +0100533 if (tgt_device)
534 btrfs_destroy_dev_replace_tgtdev(fs_info, tgt_device);
535 mutex_unlock(&dev_replace->lock_finishing_cancel_unmount);
536
Eryu Guan2fc9f6b2014-10-13 12:42:12 +0800537 return scrub_ret;
Stefan Behrense93c89c2012-11-05 17:33:06 +0100538 }
539
540 printk_in_rcu(KERN_INFO
Anand Jainde4c2962014-08-13 14:24:25 +0800541 "BTRFS: dev_replace from %s (devid %llu) to %s finished\n",
Stefan Behrense93c89c2012-11-05 17:33:06 +0100542 src_device->missing ? "<missing disk>" :
543 rcu_str_deref(src_device->name),
544 src_device->devid,
545 rcu_str_deref(tgt_device->name));
546 tgt_device->is_tgtdev_for_dev_replace = 0;
547 tgt_device->devid = src_device->devid;
548 src_device->devid = BTRFS_DEV_REPLACE_DEVID;
Stefan Behrense93c89c2012-11-05 17:33:06 +0100549 memcpy(uuid_tmp, tgt_device->uuid, sizeof(uuid_tmp));
550 memcpy(tgt_device->uuid, src_device->uuid, sizeof(tgt_device->uuid));
551 memcpy(src_device->uuid, uuid_tmp, sizeof(src_device->uuid));
Miao Xie7cc8e582014-09-03 21:35:38 +0800552 btrfs_device_set_total_bytes(tgt_device, src_device->total_bytes);
553 btrfs_device_set_disk_total_bytes(tgt_device,
554 src_device->disk_total_bytes);
555 btrfs_device_set_bytes_used(tgt_device, src_device->bytes_used);
Miao Xie935e5cc2014-09-03 21:35:33 +0800556 ASSERT(list_empty(&src_device->resized_list));
557 tgt_device->commit_total_bytes = src_device->commit_total_bytes;
Miao Xiece7213c2014-09-03 21:35:34 +0800558 tgt_device->commit_bytes_used = src_device->bytes_used;
Stefan Behrense93c89c2012-11-05 17:33:06 +0100559 if (fs_info->sb->s_bdev == src_device->bdev)
560 fs_info->sb->s_bdev = tgt_device->bdev;
561 if (fs_info->fs_devices->latest_bdev == src_device->bdev)
562 fs_info->fs_devices->latest_bdev = tgt_device->bdev;
563 list_add(&tgt_device->dev_alloc_list, &fs_info->fs_devices->alloc_list);
Miao Xie82372bc2014-09-03 21:35:44 +0800564 fs_info->fs_devices->rw_devices++;
Stefan Behrense93c89c2012-11-05 17:33:06 +0100565
Qu Wenruo12b894c2014-08-20 16:10:15 +0800566 btrfs_dev_replace_unlock(dev_replace);
567
Miao Xiec404e0d2014-01-30 16:46:55 +0800568 btrfs_rm_dev_replace_blocked(fs_info);
569
Qu Wenruo084b6e7c2014-10-30 16:52:31 +0800570 btrfs_rm_dev_replace_remove_srcdev(fs_info, src_device);
Ilya Dryomov13572722013-10-02 20:41:01 +0300571
Miao Xiec404e0d2014-01-30 16:46:55 +0800572 btrfs_rm_dev_replace_unblocked(fs_info);
573
Stefan Behrense93c89c2012-11-05 17:33:06 +0100574 /*
575 * this is again a consistent state where no dev_replace procedure
576 * is running, the target device is part of the filesystem, the
577 * source device is not part of the filesystem anymore and its 1st
578 * superblock is scratched out so that it is no longer marked to
579 * belong to this filesystem.
580 */
Miao Xie391cd9d2014-01-30 16:46:54 +0800581 mutex_unlock(&root->fs_info->chunk_mutex);
Miao Xie2196d6e2014-09-03 21:35:41 +0800582 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
Miao Xie67a2c452014-09-03 21:35:43 +0800583 mutex_unlock(&uuid_mutex);
Stefan Behrense93c89c2012-11-05 17:33:06 +0100584
Qu Wenruo084b6e7c2014-10-30 16:52:31 +0800585 /* replace the sysfs entry */
586 btrfs_kobj_rm_device(fs_info, src_device);
587 btrfs_kobj_add_device(fs_info, tgt_device);
588 btrfs_rm_dev_replace_free_srcdev(fs_info, src_device);
589
Stefan Behrense93c89c2012-11-05 17:33:06 +0100590 /* write back the superblocks */
591 trans = btrfs_start_transaction(root, 0);
592 if (!IS_ERR(trans))
593 btrfs_commit_transaction(trans, root);
594
595 mutex_unlock(&dev_replace->lock_finishing_cancel_unmount);
596
597 return 0;
598}
599
600static void btrfs_dev_replace_update_device_in_mapping_tree(
601 struct btrfs_fs_info *fs_info,
602 struct btrfs_device *srcdev,
603 struct btrfs_device *tgtdev)
604{
605 struct extent_map_tree *em_tree = &fs_info->mapping_tree.map_tree;
606 struct extent_map *em;
607 struct map_lookup *map;
608 u64 start = 0;
609 int i;
610
611 write_lock(&em_tree->lock);
612 do {
613 em = lookup_extent_mapping(em_tree, start, (u64)-1);
614 if (!em)
615 break;
616 map = (struct map_lookup *)em->bdev;
617 for (i = 0; i < map->num_stripes; i++)
618 if (srcdev == map->stripes[i].dev)
619 map->stripes[i].dev = tgtdev;
620 start = em->start + em->len;
621 free_extent_map(em);
622 } while (start);
623 write_unlock(&em_tree->lock);
624}
625
626static int btrfs_dev_replace_find_srcdev(struct btrfs_root *root, u64 srcdevid,
627 char *srcdev_name,
628 struct btrfs_device **device)
629{
630 int ret;
631
632 if (srcdevid) {
633 ret = 0;
634 *device = btrfs_find_device(root->fs_info, srcdevid, NULL,
635 NULL);
636 if (!*device)
637 ret = -ENOENT;
638 } else {
639 ret = btrfs_find_device_missing_or_by_path(root, srcdev_name,
640 device);
641 }
642 return ret;
643}
644
645void btrfs_dev_replace_status(struct btrfs_fs_info *fs_info,
646 struct btrfs_ioctl_dev_replace_args *args)
647{
648 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
Miao Xie7cc8e582014-09-03 21:35:38 +0800649 struct btrfs_device *srcdev;
Stefan Behrense93c89c2012-11-05 17:33:06 +0100650
651 btrfs_dev_replace_lock(dev_replace);
652 /* even if !dev_replace_is_valid, the values are good enough for
653 * the replace_status ioctl */
654 args->result = BTRFS_IOCTL_DEV_REPLACE_RESULT_NO_ERROR;
655 args->status.replace_state = dev_replace->replace_state;
656 args->status.time_started = dev_replace->time_started;
657 args->status.time_stopped = dev_replace->time_stopped;
658 args->status.num_write_errors =
659 atomic64_read(&dev_replace->num_write_errors);
660 args->status.num_uncorrectable_read_errors =
661 atomic64_read(&dev_replace->num_uncorrectable_read_errors);
662 switch (dev_replace->replace_state) {
663 case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED:
664 case BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED:
665 args->status.progress_1000 = 0;
666 break;
667 case BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED:
668 args->status.progress_1000 = 1000;
669 break;
670 case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED:
671 case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED:
Miao Xie7cc8e582014-09-03 21:35:38 +0800672 srcdev = dev_replace->srcdev;
Stefan Behrense93c89c2012-11-05 17:33:06 +0100673 args->status.progress_1000 = div64_u64(dev_replace->cursor_left,
Miao Xie7cc8e582014-09-03 21:35:38 +0800674 div64_u64(btrfs_device_get_total_bytes(srcdev), 1000));
Stefan Behrense93c89c2012-11-05 17:33:06 +0100675 break;
676 }
677 btrfs_dev_replace_unlock(dev_replace);
678}
679
680int btrfs_dev_replace_cancel(struct btrfs_fs_info *fs_info,
681 struct btrfs_ioctl_dev_replace_args *args)
682{
683 args->result = __btrfs_dev_replace_cancel(fs_info);
684 return 0;
685}
686
687static u64 __btrfs_dev_replace_cancel(struct btrfs_fs_info *fs_info)
688{
689 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
690 struct btrfs_device *tgt_device = NULL;
691 struct btrfs_trans_handle *trans;
692 struct btrfs_root *root = fs_info->tree_root;
693 u64 result;
694 int ret;
695
Ilya Dryomove649e582013-10-10 20:40:21 +0300696 if (fs_info->sb->s_flags & MS_RDONLY)
697 return -EROFS;
698
Stefan Behrense93c89c2012-11-05 17:33:06 +0100699 mutex_lock(&dev_replace->lock_finishing_cancel_unmount);
700 btrfs_dev_replace_lock(dev_replace);
701 switch (dev_replace->replace_state) {
702 case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED:
703 case BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED:
704 case BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED:
705 result = BTRFS_IOCTL_DEV_REPLACE_RESULT_NOT_STARTED;
706 btrfs_dev_replace_unlock(dev_replace);
707 goto leave;
708 case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED:
709 case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED:
710 result = BTRFS_IOCTL_DEV_REPLACE_RESULT_NO_ERROR;
711 tgt_device = dev_replace->tgtdev;
712 dev_replace->tgtdev = NULL;
713 dev_replace->srcdev = NULL;
714 break;
715 }
716 dev_replace->replace_state = BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED;
Zach Brown4546bca2013-10-16 12:10:32 -0700717 dev_replace->time_stopped = get_seconds();
Stefan Behrense93c89c2012-11-05 17:33:06 +0100718 dev_replace->item_needs_writeback = 1;
719 btrfs_dev_replace_unlock(dev_replace);
720 btrfs_scrub_cancel(fs_info);
721
722 trans = btrfs_start_transaction(root, 0);
723 if (IS_ERR(trans)) {
724 mutex_unlock(&dev_replace->lock_finishing_cancel_unmount);
725 return PTR_ERR(trans);
726 }
727 ret = btrfs_commit_transaction(trans, root);
728 WARN_ON(ret);
729 if (tgt_device)
730 btrfs_destroy_dev_replace_tgtdev(fs_info, tgt_device);
731
732leave:
733 mutex_unlock(&dev_replace->lock_finishing_cancel_unmount);
734 return result;
735}
736
737void btrfs_dev_replace_suspend_for_unmount(struct btrfs_fs_info *fs_info)
738{
739 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
740
741 mutex_lock(&dev_replace->lock_finishing_cancel_unmount);
742 btrfs_dev_replace_lock(dev_replace);
743 switch (dev_replace->replace_state) {
744 case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED:
745 case BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED:
746 case BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED:
747 case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED:
748 break;
749 case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED:
750 dev_replace->replace_state =
751 BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED;
Zach Brown4546bca2013-10-16 12:10:32 -0700752 dev_replace->time_stopped = get_seconds();
Stefan Behrense93c89c2012-11-05 17:33:06 +0100753 dev_replace->item_needs_writeback = 1;
Frank Holtonefe120a2013-12-20 11:37:06 -0500754 btrfs_info(fs_info, "suspending dev_replace for unmount");
Stefan Behrense93c89c2012-11-05 17:33:06 +0100755 break;
756 }
757
758 btrfs_dev_replace_unlock(dev_replace);
759 mutex_unlock(&dev_replace->lock_finishing_cancel_unmount);
760}
761
762/* resume dev_replace procedure that was interrupted by unmount */
763int btrfs_resume_dev_replace_async(struct btrfs_fs_info *fs_info)
764{
765 struct task_struct *task;
766 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
767
768 btrfs_dev_replace_lock(dev_replace);
769 switch (dev_replace->replace_state) {
770 case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED:
771 case BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED:
772 case BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED:
773 btrfs_dev_replace_unlock(dev_replace);
774 return 0;
775 case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED:
776 break;
777 case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED:
778 dev_replace->replace_state =
779 BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED;
780 break;
781 }
782 if (!dev_replace->tgtdev || !dev_replace->tgtdev->bdev) {
Frank Holtonefe120a2013-12-20 11:37:06 -0500783 btrfs_info(fs_info, "cannot continue dev_replace, tgtdev is missing");
784 btrfs_info(fs_info,
785 "you may cancel the operation after 'mount -o degraded'");
Stefan Behrense93c89c2012-11-05 17:33:06 +0100786 btrfs_dev_replace_unlock(dev_replace);
787 return 0;
788 }
789 btrfs_dev_replace_unlock(dev_replace);
790
791 WARN_ON(atomic_xchg(
792 &fs_info->mutually_exclusive_operation_running, 1));
793 task = kthread_run(btrfs_dev_replace_kthread, fs_info, "btrfs-devrepl");
Rusty Russell8c6ffba2013-07-15 11:20:32 +0930794 return PTR_ERR_OR_ZERO(task);
Stefan Behrense93c89c2012-11-05 17:33:06 +0100795}
796
797static int btrfs_dev_replace_kthread(void *data)
798{
799 struct btrfs_fs_info *fs_info = data;
800 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
801 struct btrfs_ioctl_dev_replace_args *status_args;
802 u64 progress;
803
804 status_args = kzalloc(sizeof(*status_args), GFP_NOFS);
805 if (status_args) {
806 btrfs_dev_replace_status(fs_info, status_args);
807 progress = status_args->status.progress_1000;
808 kfree(status_args);
809 do_div(progress, 10);
810 printk_in_rcu(KERN_INFO
Frank Holtonefe120a2013-12-20 11:37:06 -0500811 "BTRFS: continuing dev_replace from %s (devid %llu) to %s @%u%%\n",
812 dev_replace->srcdev->missing ? "<missing disk>" :
813 rcu_str_deref(dev_replace->srcdev->name),
814 dev_replace->srcdev->devid,
815 dev_replace->tgtdev ?
816 rcu_str_deref(dev_replace->tgtdev->name) :
817 "<missing target disk>",
818 (unsigned int)progress);
Stefan Behrense93c89c2012-11-05 17:33:06 +0100819 }
820 btrfs_dev_replace_continue_on_mount(fs_info);
821 atomic_set(&fs_info->mutually_exclusive_operation_running, 0);
822
823 return 0;
824}
825
826static int btrfs_dev_replace_continue_on_mount(struct btrfs_fs_info *fs_info)
827{
828 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
829 int ret;
830
831 ret = btrfs_scrub_dev(fs_info, dev_replace->srcdev->devid,
832 dev_replace->committed_cursor_left,
Miao Xie7cc8e582014-09-03 21:35:38 +0800833 btrfs_device_get_total_bytes(dev_replace->srcdev),
Stefan Behrense93c89c2012-11-05 17:33:06 +0100834 &dev_replace->scrub_progress, 0, 1);
835 ret = btrfs_dev_replace_finishing(fs_info, ret);
836 WARN_ON(ret);
837 return 0;
838}
839
840int btrfs_dev_replace_is_ongoing(struct btrfs_dev_replace *dev_replace)
841{
842 if (!dev_replace->is_valid)
843 return 0;
844
845 switch (dev_replace->replace_state) {
846 case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED:
847 case BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED:
848 case BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED:
849 return 0;
850 case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED:
851 case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED:
852 /*
853 * return true even if tgtdev is missing (this is
854 * something that can happen if the dev_replace
855 * procedure is suspended by an umount and then
856 * the tgtdev is missing (or "btrfs dev scan") was
857 * not called and the the filesystem is remounted
858 * in degraded state. This does not stop the
859 * dev_replace procedure. It needs to be canceled
860 * manually if the cancelation is wanted.
861 */
862 break;
863 }
864 return 1;
865}
866
867void btrfs_dev_replace_lock(struct btrfs_dev_replace *dev_replace)
868{
869 /* the beginning is just an optimization for the typical case */
870 if (atomic_read(&dev_replace->nesting_level) == 0) {
871acquire_lock:
872 /* this is not a nested case where the same thread
873 * is trying to acqurire the same lock twice */
874 mutex_lock(&dev_replace->lock);
875 mutex_lock(&dev_replace->lock_management_lock);
876 dev_replace->lock_owner = current->pid;
877 atomic_inc(&dev_replace->nesting_level);
878 mutex_unlock(&dev_replace->lock_management_lock);
879 return;
880 }
881
882 mutex_lock(&dev_replace->lock_management_lock);
883 if (atomic_read(&dev_replace->nesting_level) > 0 &&
884 dev_replace->lock_owner == current->pid) {
885 WARN_ON(!mutex_is_locked(&dev_replace->lock));
886 atomic_inc(&dev_replace->nesting_level);
887 mutex_unlock(&dev_replace->lock_management_lock);
888 return;
889 }
890
891 mutex_unlock(&dev_replace->lock_management_lock);
892 goto acquire_lock;
893}
894
895void btrfs_dev_replace_unlock(struct btrfs_dev_replace *dev_replace)
896{
897 WARN_ON(!mutex_is_locked(&dev_replace->lock));
898 mutex_lock(&dev_replace->lock_management_lock);
899 WARN_ON(atomic_read(&dev_replace->nesting_level) < 1);
900 WARN_ON(dev_replace->lock_owner != current->pid);
901 atomic_dec(&dev_replace->nesting_level);
902 if (atomic_read(&dev_replace->nesting_level) == 0) {
903 dev_replace->lock_owner = 0;
904 mutex_unlock(&dev_replace->lock_management_lock);
905 mutex_unlock(&dev_replace->lock);
906 } else {
907 mutex_unlock(&dev_replace->lock_management_lock);
908 }
909}
Miao Xiec404e0d2014-01-30 16:46:55 +0800910
911void btrfs_bio_counter_inc_noblocked(struct btrfs_fs_info *fs_info)
912{
913 percpu_counter_inc(&fs_info->bio_counter);
914}
915
Miao Xie42452152014-11-25 16:39:28 +0800916void btrfs_bio_counter_sub(struct btrfs_fs_info *fs_info, s64 amount)
Miao Xiec404e0d2014-01-30 16:46:55 +0800917{
Miao Xie42452152014-11-25 16:39:28 +0800918 percpu_counter_sub(&fs_info->bio_counter, amount);
Miao Xiec404e0d2014-01-30 16:46:55 +0800919
920 if (waitqueue_active(&fs_info->replace_wait))
921 wake_up(&fs_info->replace_wait);
922}
923
924void btrfs_bio_counter_inc_blocked(struct btrfs_fs_info *fs_info)
925{
Zhao Lei09dd7a02015-01-20 15:11:37 +0800926 while (1) {
927 percpu_counter_inc(&fs_info->bio_counter);
928 if (likely(!test_bit(BTRFS_FS_STATE_DEV_REPLACING,
929 &fs_info->fs_state)))
930 break;
931
Miao Xiec404e0d2014-01-30 16:46:55 +0800932 btrfs_bio_counter_dec(fs_info);
933 wait_event(fs_info->replace_wait,
934 !test_bit(BTRFS_FS_STATE_DEV_REPLACING,
935 &fs_info->fs_state));
Miao Xiec404e0d2014-01-30 16:46:55 +0800936 }
Miao Xiec404e0d2014-01-30 16:46:55 +0800937}