1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Copyright (C) STRATO AG 2012. All rights reserved. 4 */ 5 6 #include <linux/sched.h> 7 #include <linux/bio.h> 8 #include <linux/slab.h> 9 #include <linux/blkdev.h> 10 #include <linux/kthread.h> 11 #include <linux/math64.h> 12 #include "ctree.h" 13 #include "extent_map.h" 14 #include "disk-io.h" 15 #include "transaction.h" 16 #include "print-tree.h" 17 #include "volumes.h" 18 #include "async-thread.h" 19 #include "check-integrity.h" 20 #include "rcu-string.h" 21 #include "dev-replace.h" 22 #include "sysfs.h" 23 24 static int btrfs_dev_replace_finishing(struct btrfs_fs_info *fs_info, 25 int scrub_ret); 26 static void btrfs_dev_replace_update_device_in_mapping_tree( 27 struct btrfs_fs_info *fs_info, 28 struct btrfs_device *srcdev, 29 struct btrfs_device *tgtdev); 30 static int btrfs_dev_replace_kthread(void *data); 31 32 int btrfs_init_dev_replace(struct btrfs_fs_info *fs_info) 33 { 34 struct btrfs_key key; 35 struct btrfs_root *dev_root = fs_info->dev_root; 36 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace; 37 struct extent_buffer *eb; 38 int slot; 39 int ret = 0; 40 struct btrfs_path *path = NULL; 41 int item_size; 42 struct btrfs_dev_replace_item *ptr; 43 u64 src_devid; 44 45 path = btrfs_alloc_path(); 46 if (!path) { 47 ret = -ENOMEM; 48 goto out; 49 } 50 51 key.objectid = 0; 52 key.type = BTRFS_DEV_REPLACE_KEY; 53 key.offset = 0; 54 ret = btrfs_search_slot(NULL, dev_root, &key, path, 0, 0); 55 if (ret) { 56 no_valid_dev_replace_entry_found: 57 ret = 0; 58 dev_replace->replace_state = 59 BTRFS_DEV_REPLACE_ITEM_STATE_NEVER_STARTED; 60 dev_replace->cont_reading_from_srcdev_mode = 61 BTRFS_DEV_REPLACE_ITEM_CONT_READING_FROM_SRCDEV_MODE_ALWAYS; 62 dev_replace->replace_state = 0; 63 dev_replace->time_started = 0; 64 dev_replace->time_stopped = 0; 65 atomic64_set(&dev_replace->num_write_errors, 0); 66 atomic64_set(&dev_replace->num_uncorrectable_read_errors, 0); 67 dev_replace->cursor_left = 0; 68 dev_replace->committed_cursor_left = 0; 69 dev_replace->cursor_left_last_write_of_item = 0; 70 dev_replace->cursor_right = 0; 71 dev_replace->srcdev = NULL; 72 dev_replace->tgtdev = NULL; 73 dev_replace->is_valid = 0; 74 dev_replace->item_needs_writeback = 0; 75 goto out; 76 } 77 slot = path->slots[0]; 78 eb = path->nodes[0]; 79 item_size = btrfs_item_size_nr(eb, slot); 80 ptr = btrfs_item_ptr(eb, slot, struct btrfs_dev_replace_item); 81 82 if (item_size != sizeof(struct btrfs_dev_replace_item)) { 83 btrfs_warn(fs_info, 84 "dev_replace entry found has unexpected size, ignore entry"); 85 goto no_valid_dev_replace_entry_found; 86 } 87 88 src_devid = btrfs_dev_replace_src_devid(eb, ptr); 89 dev_replace->cont_reading_from_srcdev_mode = 90 btrfs_dev_replace_cont_reading_from_srcdev_mode(eb, ptr); 91 dev_replace->replace_state = btrfs_dev_replace_replace_state(eb, ptr); 92 dev_replace->time_started = btrfs_dev_replace_time_started(eb, ptr); 93 dev_replace->time_stopped = 94 btrfs_dev_replace_time_stopped(eb, ptr); 95 atomic64_set(&dev_replace->num_write_errors, 96 btrfs_dev_replace_num_write_errors(eb, ptr)); 97 atomic64_set(&dev_replace->num_uncorrectable_read_errors, 98 btrfs_dev_replace_num_uncorrectable_read_errors(eb, ptr)); 99 dev_replace->cursor_left = btrfs_dev_replace_cursor_left(eb, ptr); 100 dev_replace->committed_cursor_left = dev_replace->cursor_left; 101 dev_replace->cursor_left_last_write_of_item = dev_replace->cursor_left; 102 dev_replace->cursor_right = btrfs_dev_replace_cursor_right(eb, ptr); 103 dev_replace->is_valid = 1; 104 105 dev_replace->item_needs_writeback = 0; 106 switch (dev_replace->replace_state) { 107 case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED: 108 case BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED: 109 case BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED: 110 dev_replace->srcdev = NULL; 111 dev_replace->tgtdev = NULL; 112 break; 113 case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED: 114 case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED: 115 dev_replace->srcdev = btrfs_find_device(fs_info, src_devid, 116 NULL, NULL); 117 dev_replace->tgtdev = btrfs_find_device(fs_info, 118 BTRFS_DEV_REPLACE_DEVID, 119 NULL, NULL); 120 /* 121 * allow 'btrfs dev replace_cancel' if src/tgt device is 122 * missing 123 */ 124 if (!dev_replace->srcdev && 125 !btrfs_test_opt(fs_info, DEGRADED)) { 126 ret = -EIO; 127 btrfs_warn(fs_info, 128 "cannot mount because device replace operation is ongoing and"); 129 btrfs_warn(fs_info, 130 "srcdev (devid %llu) is missing, need to run 'btrfs dev scan'?", 131 src_devid); 132 } 133 if (!dev_replace->tgtdev && 134 !btrfs_test_opt(fs_info, DEGRADED)) { 135 ret = -EIO; 136 btrfs_warn(fs_info, 137 "cannot mount because device replace operation is ongoing and"); 138 btrfs_warn(fs_info, 139 "tgtdev (devid %llu) is missing, need to run 'btrfs dev scan'?", 140 BTRFS_DEV_REPLACE_DEVID); 141 } 142 if (dev_replace->tgtdev) { 143 if (dev_replace->srcdev) { 144 dev_replace->tgtdev->total_bytes = 145 dev_replace->srcdev->total_bytes; 146 dev_replace->tgtdev->disk_total_bytes = 147 dev_replace->srcdev->disk_total_bytes; 148 dev_replace->tgtdev->commit_total_bytes = 149 dev_replace->srcdev->commit_total_bytes; 150 dev_replace->tgtdev->bytes_used = 151 dev_replace->srcdev->bytes_used; 152 dev_replace->tgtdev->commit_bytes_used = 153 dev_replace->srcdev->commit_bytes_used; 154 } 155 set_bit(BTRFS_DEV_STATE_REPLACE_TGT, 156 &dev_replace->tgtdev->dev_state); 157 158 WARN_ON(fs_info->fs_devices->rw_devices == 0); 159 dev_replace->tgtdev->io_width = fs_info->sectorsize; 160 dev_replace->tgtdev->io_align = fs_info->sectorsize; 161 dev_replace->tgtdev->sector_size = fs_info->sectorsize; 162 dev_replace->tgtdev->fs_info = fs_info; 163 set_bit(BTRFS_DEV_STATE_IN_FS_METADATA, 164 &dev_replace->tgtdev->dev_state); 165 } 166 break; 167 } 168 169 out: 170 btrfs_free_path(path); 171 return ret; 172 } 173 174 /* 175 * Initialize a new device for device replace target from a given source dev 176 * and path. 177 * 178 * Return 0 and new device in @device_out, otherwise return < 0 179 */ 180 static int btrfs_init_dev_replace_tgtdev(struct btrfs_fs_info *fs_info, 181 const char *device_path, 182 struct btrfs_device *srcdev, 183 struct btrfs_device **device_out) 184 { 185 struct btrfs_device *device; 186 struct block_device *bdev; 187 struct list_head *devices; 188 struct rcu_string *name; 189 u64 devid = BTRFS_DEV_REPLACE_DEVID; 190 int ret = 0; 191 192 *device_out = NULL; 193 if (fs_info->fs_devices->seeding) { 194 btrfs_err(fs_info, "the filesystem is a seed filesystem!"); 195 return -EINVAL; 196 } 197 198 bdev = blkdev_get_by_path(device_path, FMODE_WRITE | FMODE_EXCL, 199 fs_info->bdev_holder); 200 if (IS_ERR(bdev)) { 201 btrfs_err(fs_info, "target device %s is invalid!", device_path); 202 return PTR_ERR(bdev); 203 } 204 205 filemap_write_and_wait(bdev->bd_inode->i_mapping); 206 207 devices = &fs_info->fs_devices->devices; 208 list_for_each_entry(device, devices, dev_list) { 209 if (device->bdev == bdev) { 210 btrfs_err(fs_info, 211 "target device is in the filesystem!"); 212 ret = -EEXIST; 213 goto error; 214 } 215 } 216 217 218 if (i_size_read(bdev->bd_inode) < 219 btrfs_device_get_total_bytes(srcdev)) { 220 btrfs_err(fs_info, 221 "target device is smaller than source device!"); 222 ret = -EINVAL; 223 goto error; 224 } 225 226 227 device = btrfs_alloc_device(NULL, &devid, NULL); 228 if (IS_ERR(device)) { 229 ret = PTR_ERR(device); 230 goto error; 231 } 232 233 name = rcu_string_strdup(device_path, GFP_KERNEL); 234 if (!name) { 235 btrfs_free_device(device); 236 ret = -ENOMEM; 237 goto error; 238 } 239 rcu_assign_pointer(device->name, name); 240 241 mutex_lock(&fs_info->fs_devices->device_list_mutex); 242 set_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state); 243 device->generation = 0; 244 device->io_width = fs_info->sectorsize; 245 device->io_align = fs_info->sectorsize; 246 device->sector_size = fs_info->sectorsize; 247 device->total_bytes = btrfs_device_get_total_bytes(srcdev); 248 device->disk_total_bytes = btrfs_device_get_disk_total_bytes(srcdev); 249 device->bytes_used = btrfs_device_get_bytes_used(srcdev); 250 device->commit_total_bytes = srcdev->commit_total_bytes; 251 device->commit_bytes_used = device->bytes_used; 252 device->fs_info = fs_info; 253 device->bdev = bdev; 254 set_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state); 255 set_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state); 256 device->mode = FMODE_EXCL; 257 device->dev_stats_valid = 1; 258 set_blocksize(device->bdev, BTRFS_BDEV_BLOCKSIZE); 259 device->fs_devices = fs_info->fs_devices; 260 list_add(&device->dev_list, &fs_info->fs_devices->devices); 261 fs_info->fs_devices->num_devices++; 262 fs_info->fs_devices->open_devices++; 263 mutex_unlock(&fs_info->fs_devices->device_list_mutex); 264 265 *device_out = device; 266 return 0; 267 268 error: 269 blkdev_put(bdev, FMODE_EXCL); 270 return ret; 271 } 272 273 /* 274 * called from commit_transaction. Writes changed device replace state to 275 * disk. 276 */ 277 int btrfs_run_dev_replace(struct btrfs_trans_handle *trans, 278 struct btrfs_fs_info *fs_info) 279 { 280 int ret; 281 struct btrfs_root *dev_root = fs_info->dev_root; 282 struct btrfs_path *path; 283 struct btrfs_key key; 284 struct extent_buffer *eb; 285 struct btrfs_dev_replace_item *ptr; 286 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace; 287 288 btrfs_dev_replace_read_lock(dev_replace); 289 if (!dev_replace->is_valid || 290 !dev_replace->item_needs_writeback) { 291 btrfs_dev_replace_read_unlock(dev_replace); 292 return 0; 293 } 294 btrfs_dev_replace_read_unlock(dev_replace); 295 296 key.objectid = 0; 297 key.type = BTRFS_DEV_REPLACE_KEY; 298 key.offset = 0; 299 300 path = btrfs_alloc_path(); 301 if (!path) { 302 ret = -ENOMEM; 303 goto out; 304 } 305 ret = btrfs_search_slot(trans, dev_root, &key, path, -1, 1); 306 if (ret < 0) { 307 btrfs_warn(fs_info, 308 "error %d while searching for dev_replace item!", 309 ret); 310 goto out; 311 } 312 313 if (ret == 0 && 314 btrfs_item_size_nr(path->nodes[0], path->slots[0]) < sizeof(*ptr)) { 315 /* 316 * need to delete old one and insert a new one. 317 * Since no attempt is made to recover any old state, if the 318 * dev_replace state is 'running', the data on the target 319 * drive is lost. 320 * It would be possible to recover the state: just make sure 321 * that the beginning of the item is never changed and always 322 * contains all the essential information. Then read this 323 * minimal set of information and use it as a base for the 324 * new state. 325 */ 326 ret = btrfs_del_item(trans, dev_root, path); 327 if (ret != 0) { 328 btrfs_warn(fs_info, 329 "delete too small dev_replace item failed %d!", 330 ret); 331 goto out; 332 } 333 ret = 1; 334 } 335 336 if (ret == 1) { 337 /* need to insert a new item */ 338 btrfs_release_path(path); 339 ret = btrfs_insert_empty_item(trans, dev_root, path, 340 &key, sizeof(*ptr)); 341 if (ret < 0) { 342 btrfs_warn(fs_info, 343 "insert dev_replace item failed %d!", ret); 344 goto out; 345 } 346 } 347 348 eb = path->nodes[0]; 349 ptr = btrfs_item_ptr(eb, path->slots[0], 350 struct btrfs_dev_replace_item); 351 352 btrfs_dev_replace_write_lock(dev_replace); 353 if (dev_replace->srcdev) 354 btrfs_set_dev_replace_src_devid(eb, ptr, 355 dev_replace->srcdev->devid); 356 else 357 btrfs_set_dev_replace_src_devid(eb, ptr, (u64)-1); 358 btrfs_set_dev_replace_cont_reading_from_srcdev_mode(eb, ptr, 359 dev_replace->cont_reading_from_srcdev_mode); 360 btrfs_set_dev_replace_replace_state(eb, ptr, 361 dev_replace->replace_state); 362 btrfs_set_dev_replace_time_started(eb, ptr, dev_replace->time_started); 363 btrfs_set_dev_replace_time_stopped(eb, ptr, dev_replace->time_stopped); 364 btrfs_set_dev_replace_num_write_errors(eb, ptr, 365 atomic64_read(&dev_replace->num_write_errors)); 366 btrfs_set_dev_replace_num_uncorrectable_read_errors(eb, ptr, 367 atomic64_read(&dev_replace->num_uncorrectable_read_errors)); 368 dev_replace->cursor_left_last_write_of_item = 369 dev_replace->cursor_left; 370 btrfs_set_dev_replace_cursor_left(eb, ptr, 371 dev_replace->cursor_left_last_write_of_item); 372 btrfs_set_dev_replace_cursor_right(eb, ptr, 373 dev_replace->cursor_right); 374 dev_replace->item_needs_writeback = 0; 375 btrfs_dev_replace_write_unlock(dev_replace); 376 377 btrfs_mark_buffer_dirty(eb); 378 379 out: 380 btrfs_free_path(path); 381 382 return ret; 383 } 384 385 void btrfs_after_dev_replace_commit(struct btrfs_fs_info *fs_info) 386 { 387 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace; 388 389 dev_replace->committed_cursor_left = 390 dev_replace->cursor_left_last_write_of_item; 391 } 392 393 static char* btrfs_dev_name(struct btrfs_device *device) 394 { 395 if (!device || test_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state)) 396 return "<missing disk>"; 397 else 398 return rcu_str_deref(device->name); 399 } 400 401 int btrfs_dev_replace_start(struct btrfs_fs_info *fs_info, 402 const char *tgtdev_name, u64 srcdevid, const char *srcdev_name, 403 int read_src) 404 { 405 struct btrfs_root *root = fs_info->dev_root; 406 struct btrfs_trans_handle *trans; 407 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace; 408 int ret; 409 struct btrfs_device *tgt_device = NULL; 410 struct btrfs_device *src_device = NULL; 411 412 src_device = btrfs_find_device_by_devspec(fs_info, srcdevid, 413 srcdev_name); 414 if (IS_ERR(src_device)) 415 return PTR_ERR(src_device); 416 417 ret = btrfs_init_dev_replace_tgtdev(fs_info, tgtdev_name, 418 src_device, &tgt_device); 419 if (ret) 420 return ret; 421 422 /* 423 * Here we commit the transaction to make sure commit_total_bytes 424 * of all the devices are updated. 425 */ 426 trans = btrfs_attach_transaction(root); 427 if (!IS_ERR(trans)) { 428 ret = btrfs_commit_transaction(trans); 429 if (ret) 430 return ret; 431 } else if (PTR_ERR(trans) != -ENOENT) { 432 return PTR_ERR(trans); 433 } 434 435 btrfs_dev_replace_write_lock(dev_replace); 436 switch (dev_replace->replace_state) { 437 case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED: 438 case BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED: 439 case BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED: 440 break; 441 case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED: 442 case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED: 443 ASSERT(0); 444 ret = BTRFS_IOCTL_DEV_REPLACE_RESULT_ALREADY_STARTED; 445 goto leave; 446 } 447 448 dev_replace->cont_reading_from_srcdev_mode = read_src; 449 WARN_ON(!src_device); 450 dev_replace->srcdev = src_device; 451 dev_replace->tgtdev = tgt_device; 452 453 btrfs_info_in_rcu(fs_info, 454 "dev_replace from %s (devid %llu) to %s started", 455 btrfs_dev_name(src_device), 456 src_device->devid, 457 rcu_str_deref(tgt_device->name)); 458 459 /* 460 * from now on, the writes to the srcdev are all duplicated to 461 * go to the tgtdev as well (refer to btrfs_map_block()). 462 */ 463 dev_replace->replace_state = BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED; 464 dev_replace->time_started = ktime_get_real_seconds(); 465 dev_replace->cursor_left = 0; 466 dev_replace->committed_cursor_left = 0; 467 dev_replace->cursor_left_last_write_of_item = 0; 468 dev_replace->cursor_right = 0; 469 dev_replace->is_valid = 1; 470 dev_replace->item_needs_writeback = 1; 471 atomic64_set(&dev_replace->num_write_errors, 0); 472 atomic64_set(&dev_replace->num_uncorrectable_read_errors, 0); 473 btrfs_dev_replace_write_unlock(dev_replace); 474 475 ret = btrfs_sysfs_add_device_link(tgt_device->fs_devices, tgt_device); 476 if (ret) 477 btrfs_err(fs_info, "kobj add dev failed %d", ret); 478 479 btrfs_wait_ordered_roots(fs_info, U64_MAX, 0, (u64)-1); 480 481 /* force writing the updated state information to disk */ 482 trans = btrfs_start_transaction(root, 0); 483 if (IS_ERR(trans)) { 484 ret = PTR_ERR(trans); 485 btrfs_dev_replace_write_lock(dev_replace); 486 dev_replace->replace_state = 487 BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED; 488 dev_replace->srcdev = NULL; 489 dev_replace->tgtdev = NULL; 490 goto leave; 491 } 492 493 ret = btrfs_commit_transaction(trans); 494 WARN_ON(ret); 495 496 /* the disk copy procedure reuses the scrub code */ 497 ret = btrfs_scrub_dev(fs_info, src_device->devid, 0, 498 btrfs_device_get_total_bytes(src_device), 499 &dev_replace->scrub_progress, 0, 1); 500 501 ret = btrfs_dev_replace_finishing(fs_info, ret); 502 if (ret == -EINPROGRESS) { 503 ret = BTRFS_IOCTL_DEV_REPLACE_RESULT_SCRUB_INPROGRESS; 504 } else { 505 WARN_ON(ret); 506 } 507 508 return ret; 509 510 leave: 511 btrfs_dev_replace_write_unlock(dev_replace); 512 btrfs_destroy_dev_replace_tgtdev(tgt_device); 513 return ret; 514 } 515 516 int btrfs_dev_replace_by_ioctl(struct btrfs_fs_info *fs_info, 517 struct btrfs_ioctl_dev_replace_args *args) 518 { 519 int ret; 520 521 switch (args->start.cont_reading_from_srcdev_mode) { 522 case BTRFS_IOCTL_DEV_REPLACE_CONT_READING_FROM_SRCDEV_MODE_ALWAYS: 523 case BTRFS_IOCTL_DEV_REPLACE_CONT_READING_FROM_SRCDEV_MODE_AVOID: 524 break; 525 default: 526 return -EINVAL; 527 } 528 529 if ((args->start.srcdevid == 0 && args->start.srcdev_name[0] == '\0') || 530 args->start.tgtdev_name[0] == '\0') 531 return -EINVAL; 532 533 ret = btrfs_dev_replace_start(fs_info, args->start.tgtdev_name, 534 args->start.srcdevid, 535 args->start.srcdev_name, 536 args->start.cont_reading_from_srcdev_mode); 537 args->result = ret; 538 /* don't warn if EINPROGRESS, someone else might be running scrub */ 539 if (ret == BTRFS_IOCTL_DEV_REPLACE_RESULT_SCRUB_INPROGRESS) 540 ret = 0; 541 542 return ret; 543 } 544 545 /* 546 * blocked until all in-flight bios operations are finished. 547 */ 548 static void btrfs_rm_dev_replace_blocked(struct btrfs_fs_info *fs_info) 549 { 550 set_bit(BTRFS_FS_STATE_DEV_REPLACING, &fs_info->fs_state); 551 wait_event(fs_info->replace_wait, !percpu_counter_sum( 552 &fs_info->bio_counter)); 553 } 554 555 /* 556 * we have removed target device, it is safe to allow new bios request. 557 */ 558 static void btrfs_rm_dev_replace_unblocked(struct btrfs_fs_info *fs_info) 559 { 560 clear_bit(BTRFS_FS_STATE_DEV_REPLACING, &fs_info->fs_state); 561 wake_up(&fs_info->replace_wait); 562 } 563 564 static int btrfs_dev_replace_finishing(struct btrfs_fs_info *fs_info, 565 int scrub_ret) 566 { 567 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace; 568 struct btrfs_device *tgt_device; 569 struct btrfs_device *src_device; 570 struct btrfs_root *root = fs_info->tree_root; 571 u8 uuid_tmp[BTRFS_UUID_SIZE]; 572 struct btrfs_trans_handle *trans; 573 int ret = 0; 574 575 /* don't allow cancel or unmount to disturb the finishing procedure */ 576 mutex_lock(&dev_replace->lock_finishing_cancel_unmount); 577 578 btrfs_dev_replace_read_lock(dev_replace); 579 /* was the operation canceled, or is it finished? */ 580 if (dev_replace->replace_state != 581 BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED) { 582 btrfs_dev_replace_read_unlock(dev_replace); 583 mutex_unlock(&dev_replace->lock_finishing_cancel_unmount); 584 return 0; 585 } 586 587 tgt_device = dev_replace->tgtdev; 588 src_device = dev_replace->srcdev; 589 btrfs_dev_replace_read_unlock(dev_replace); 590 591 /* 592 * flush all outstanding I/O and inode extent mappings before the 593 * copy operation is declared as being finished 594 */ 595 ret = btrfs_start_delalloc_roots(fs_info, -1); 596 if (ret) { 597 mutex_unlock(&dev_replace->lock_finishing_cancel_unmount); 598 return ret; 599 } 600 btrfs_wait_ordered_roots(fs_info, U64_MAX, 0, (u64)-1); 601 602 trans = btrfs_start_transaction(root, 0); 603 if (IS_ERR(trans)) { 604 mutex_unlock(&dev_replace->lock_finishing_cancel_unmount); 605 return PTR_ERR(trans); 606 } 607 ret = btrfs_commit_transaction(trans); 608 WARN_ON(ret); 609 610 /* keep away write_all_supers() during the finishing procedure */ 611 mutex_lock(&fs_info->fs_devices->device_list_mutex); 612 mutex_lock(&fs_info->chunk_mutex); 613 btrfs_dev_replace_write_lock(dev_replace); 614 dev_replace->replace_state = 615 scrub_ret ? BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED 616 : BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED; 617 dev_replace->tgtdev = NULL; 618 dev_replace->srcdev = NULL; 619 dev_replace->time_stopped = ktime_get_real_seconds(); 620 dev_replace->item_needs_writeback = 1; 621 622 /* replace old device with new one in mapping tree */ 623 if (!scrub_ret) { 624 btrfs_dev_replace_update_device_in_mapping_tree(fs_info, 625 src_device, 626 tgt_device); 627 } else { 628 btrfs_err_in_rcu(fs_info, 629 "btrfs_scrub_dev(%s, %llu, %s) failed %d", 630 btrfs_dev_name(src_device), 631 src_device->devid, 632 rcu_str_deref(tgt_device->name), scrub_ret); 633 btrfs_dev_replace_write_unlock(dev_replace); 634 mutex_unlock(&fs_info->chunk_mutex); 635 mutex_unlock(&fs_info->fs_devices->device_list_mutex); 636 btrfs_rm_dev_replace_blocked(fs_info); 637 if (tgt_device) 638 btrfs_destroy_dev_replace_tgtdev(tgt_device); 639 btrfs_rm_dev_replace_unblocked(fs_info); 640 mutex_unlock(&dev_replace->lock_finishing_cancel_unmount); 641 642 return scrub_ret; 643 } 644 645 btrfs_info_in_rcu(fs_info, 646 "dev_replace from %s (devid %llu) to %s finished", 647 btrfs_dev_name(src_device), 648 src_device->devid, 649 rcu_str_deref(tgt_device->name)); 650 clear_bit(BTRFS_DEV_STATE_REPLACE_TGT, &tgt_device->dev_state); 651 tgt_device->devid = src_device->devid; 652 src_device->devid = BTRFS_DEV_REPLACE_DEVID; 653 memcpy(uuid_tmp, tgt_device->uuid, sizeof(uuid_tmp)); 654 memcpy(tgt_device->uuid, src_device->uuid, sizeof(tgt_device->uuid)); 655 memcpy(src_device->uuid, uuid_tmp, sizeof(src_device->uuid)); 656 btrfs_device_set_total_bytes(tgt_device, src_device->total_bytes); 657 btrfs_device_set_disk_total_bytes(tgt_device, 658 src_device->disk_total_bytes); 659 btrfs_device_set_bytes_used(tgt_device, src_device->bytes_used); 660 ASSERT(list_empty(&src_device->resized_list)); 661 tgt_device->commit_total_bytes = src_device->commit_total_bytes; 662 tgt_device->commit_bytes_used = src_device->bytes_used; 663 664 btrfs_assign_next_active_device(src_device, tgt_device); 665 666 list_add(&tgt_device->dev_alloc_list, &fs_info->fs_devices->alloc_list); 667 fs_info->fs_devices->rw_devices++; 668 669 btrfs_dev_replace_write_unlock(dev_replace); 670 671 btrfs_rm_dev_replace_blocked(fs_info); 672 673 btrfs_rm_dev_replace_remove_srcdev(src_device); 674 675 btrfs_rm_dev_replace_unblocked(fs_info); 676 677 /* 678 * Increment dev_stats_ccnt so that btrfs_run_dev_stats() will 679 * update on-disk dev stats value during commit transaction 680 */ 681 atomic_inc(&tgt_device->dev_stats_ccnt); 682 683 /* 684 * this is again a consistent state where no dev_replace procedure 685 * is running, the target device is part of the filesystem, the 686 * source device is not part of the filesystem anymore and its 1st 687 * superblock is scratched out so that it is no longer marked to 688 * belong to this filesystem. 689 */ 690 mutex_unlock(&fs_info->chunk_mutex); 691 mutex_unlock(&fs_info->fs_devices->device_list_mutex); 692 693 /* replace the sysfs entry */ 694 btrfs_sysfs_rm_device_link(fs_info->fs_devices, src_device); 695 btrfs_rm_dev_replace_free_srcdev(fs_info, src_device); 696 697 /* write back the superblocks */ 698 trans = btrfs_start_transaction(root, 0); 699 if (!IS_ERR(trans)) 700 btrfs_commit_transaction(trans); 701 702 mutex_unlock(&dev_replace->lock_finishing_cancel_unmount); 703 704 return 0; 705 } 706 707 static void btrfs_dev_replace_update_device_in_mapping_tree( 708 struct btrfs_fs_info *fs_info, 709 struct btrfs_device *srcdev, 710 struct btrfs_device *tgtdev) 711 { 712 struct extent_map_tree *em_tree = &fs_info->mapping_tree.map_tree; 713 struct extent_map *em; 714 struct map_lookup *map; 715 u64 start = 0; 716 int i; 717 718 write_lock(&em_tree->lock); 719 do { 720 em = lookup_extent_mapping(em_tree, start, (u64)-1); 721 if (!em) 722 break; 723 map = em->map_lookup; 724 for (i = 0; i < map->num_stripes; i++) 725 if (srcdev == map->stripes[i].dev) 726 map->stripes[i].dev = tgtdev; 727 start = em->start + em->len; 728 free_extent_map(em); 729 } while (start); 730 write_unlock(&em_tree->lock); 731 } 732 733 /* 734 * Read progress of device replace status according to the state and last 735 * stored position. The value format is the same as for 736 * btrfs_dev_replace::progress_1000 737 */ 738 static u64 btrfs_dev_replace_progress(struct btrfs_fs_info *fs_info) 739 { 740 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace; 741 u64 ret = 0; 742 743 switch (dev_replace->replace_state) { 744 case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED: 745 case BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED: 746 ret = 0; 747 break; 748 case BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED: 749 ret = 1000; 750 break; 751 case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED: 752 case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED: 753 ret = div64_u64(dev_replace->cursor_left, 754 div_u64(btrfs_device_get_total_bytes( 755 dev_replace->srcdev), 1000)); 756 break; 757 } 758 759 return ret; 760 } 761 762 void btrfs_dev_replace_status(struct btrfs_fs_info *fs_info, 763 struct btrfs_ioctl_dev_replace_args *args) 764 { 765 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace; 766 767 btrfs_dev_replace_read_lock(dev_replace); 768 /* even if !dev_replace_is_valid, the values are good enough for 769 * the replace_status ioctl */ 770 args->result = BTRFS_IOCTL_DEV_REPLACE_RESULT_NO_ERROR; 771 args->status.replace_state = dev_replace->replace_state; 772 args->status.time_started = dev_replace->time_started; 773 args->status.time_stopped = dev_replace->time_stopped; 774 args->status.num_write_errors = 775 atomic64_read(&dev_replace->num_write_errors); 776 args->status.num_uncorrectable_read_errors = 777 atomic64_read(&dev_replace->num_uncorrectable_read_errors); 778 args->status.progress_1000 = btrfs_dev_replace_progress(fs_info); 779 btrfs_dev_replace_read_unlock(dev_replace); 780 } 781 782 int btrfs_dev_replace_cancel(struct btrfs_fs_info *fs_info) 783 { 784 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace; 785 struct btrfs_device *tgt_device = NULL; 786 struct btrfs_device *src_device = NULL; 787 struct btrfs_trans_handle *trans; 788 struct btrfs_root *root = fs_info->tree_root; 789 int result; 790 int ret; 791 792 if (sb_rdonly(fs_info->sb)) 793 return -EROFS; 794 795 mutex_lock(&dev_replace->lock_finishing_cancel_unmount); 796 btrfs_dev_replace_write_lock(dev_replace); 797 switch (dev_replace->replace_state) { 798 case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED: 799 case BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED: 800 case BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED: 801 result = BTRFS_IOCTL_DEV_REPLACE_RESULT_NOT_STARTED; 802 btrfs_dev_replace_write_unlock(dev_replace); 803 goto leave; 804 case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED: 805 case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED: 806 result = BTRFS_IOCTL_DEV_REPLACE_RESULT_NO_ERROR; 807 tgt_device = dev_replace->tgtdev; 808 src_device = dev_replace->srcdev; 809 dev_replace->tgtdev = NULL; 810 dev_replace->srcdev = NULL; 811 break; 812 } 813 dev_replace->replace_state = BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED; 814 dev_replace->time_stopped = ktime_get_real_seconds(); 815 dev_replace->item_needs_writeback = 1; 816 btrfs_dev_replace_write_unlock(dev_replace); 817 btrfs_scrub_cancel(fs_info); 818 819 trans = btrfs_start_transaction(root, 0); 820 if (IS_ERR(trans)) { 821 mutex_unlock(&dev_replace->lock_finishing_cancel_unmount); 822 return PTR_ERR(trans); 823 } 824 ret = btrfs_commit_transaction(trans); 825 WARN_ON(ret); 826 827 btrfs_info_in_rcu(fs_info, 828 "dev_replace from %s (devid %llu) to %s canceled", 829 btrfs_dev_name(src_device), src_device->devid, 830 btrfs_dev_name(tgt_device)); 831 832 if (tgt_device) 833 btrfs_destroy_dev_replace_tgtdev(tgt_device); 834 835 leave: 836 mutex_unlock(&dev_replace->lock_finishing_cancel_unmount); 837 return result; 838 } 839 840 void btrfs_dev_replace_suspend_for_unmount(struct btrfs_fs_info *fs_info) 841 { 842 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace; 843 844 mutex_lock(&dev_replace->lock_finishing_cancel_unmount); 845 btrfs_dev_replace_write_lock(dev_replace); 846 switch (dev_replace->replace_state) { 847 case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED: 848 case BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED: 849 case BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED: 850 case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED: 851 break; 852 case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED: 853 dev_replace->replace_state = 854 BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED; 855 dev_replace->time_stopped = ktime_get_real_seconds(); 856 dev_replace->item_needs_writeback = 1; 857 btrfs_info(fs_info, "suspending dev_replace for unmount"); 858 break; 859 } 860 861 btrfs_dev_replace_write_unlock(dev_replace); 862 mutex_unlock(&dev_replace->lock_finishing_cancel_unmount); 863 } 864 865 /* resume dev_replace procedure that was interrupted by unmount */ 866 int btrfs_resume_dev_replace_async(struct btrfs_fs_info *fs_info) 867 { 868 struct task_struct *task; 869 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace; 870 871 btrfs_dev_replace_write_lock(dev_replace); 872 switch (dev_replace->replace_state) { 873 case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED: 874 case BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED: 875 case BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED: 876 btrfs_dev_replace_write_unlock(dev_replace); 877 return 0; 878 case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED: 879 break; 880 case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED: 881 dev_replace->replace_state = 882 BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED; 883 break; 884 } 885 if (!dev_replace->tgtdev || !dev_replace->tgtdev->bdev) { 886 btrfs_info(fs_info, 887 "cannot continue dev_replace, tgtdev is missing"); 888 btrfs_info(fs_info, 889 "you may cancel the operation after 'mount -o degraded'"); 890 btrfs_dev_replace_write_unlock(dev_replace); 891 return 0; 892 } 893 btrfs_dev_replace_write_unlock(dev_replace); 894 895 /* 896 * This could collide with a paused balance, but the exclusive op logic 897 * should never allow both to start and pause. We don't want to allow 898 * dev-replace to start anyway. 899 */ 900 if (test_and_set_bit(BTRFS_FS_EXCL_OP, &fs_info->flags)) { 901 btrfs_info(fs_info, 902 "cannot resume dev-replace, other exclusive operation running"); 903 return 0; 904 } 905 906 task = kthread_run(btrfs_dev_replace_kthread, fs_info, "btrfs-devrepl"); 907 return PTR_ERR_OR_ZERO(task); 908 } 909 910 static int btrfs_dev_replace_kthread(void *data) 911 { 912 struct btrfs_fs_info *fs_info = data; 913 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace; 914 u64 progress; 915 int ret; 916 917 progress = btrfs_dev_replace_progress(fs_info); 918 progress = div_u64(progress, 10); 919 btrfs_info_in_rcu(fs_info, 920 "continuing dev_replace from %s (devid %llu) to target %s @%u%%", 921 btrfs_dev_name(dev_replace->srcdev), 922 dev_replace->srcdev->devid, 923 btrfs_dev_name(dev_replace->tgtdev), 924 (unsigned int)progress); 925 926 ret = btrfs_scrub_dev(fs_info, dev_replace->srcdev->devid, 927 dev_replace->committed_cursor_left, 928 btrfs_device_get_total_bytes(dev_replace->srcdev), 929 &dev_replace->scrub_progress, 0, 1); 930 ret = btrfs_dev_replace_finishing(fs_info, ret); 931 WARN_ON(ret); 932 933 clear_bit(BTRFS_FS_EXCL_OP, &fs_info->flags); 934 return 0; 935 } 936 937 int btrfs_dev_replace_is_ongoing(struct btrfs_dev_replace *dev_replace) 938 { 939 if (!dev_replace->is_valid) 940 return 0; 941 942 switch (dev_replace->replace_state) { 943 case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED: 944 case BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED: 945 case BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED: 946 return 0; 947 case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED: 948 case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED: 949 /* 950 * return true even if tgtdev is missing (this is 951 * something that can happen if the dev_replace 952 * procedure is suspended by an umount and then 953 * the tgtdev is missing (or "btrfs dev scan") was 954 * not called and the the filesystem is remounted 955 * in degraded state. This does not stop the 956 * dev_replace procedure. It needs to be canceled 957 * manually if the cancellation is wanted. 958 */ 959 break; 960 } 961 return 1; 962 } 963 964 void btrfs_dev_replace_read_lock(struct btrfs_dev_replace *dev_replace) 965 { 966 read_lock(&dev_replace->lock); 967 } 968 969 void btrfs_dev_replace_read_unlock(struct btrfs_dev_replace *dev_replace) 970 { 971 read_unlock(&dev_replace->lock); 972 } 973 974 void btrfs_dev_replace_write_lock(struct btrfs_dev_replace *dev_replace) 975 { 976 again: 977 wait_event(dev_replace->read_lock_wq, 978 atomic_read(&dev_replace->blocking_readers) == 0); 979 write_lock(&dev_replace->lock); 980 if (atomic_read(&dev_replace->blocking_readers)) { 981 write_unlock(&dev_replace->lock); 982 goto again; 983 } 984 } 985 986 void btrfs_dev_replace_write_unlock(struct btrfs_dev_replace *dev_replace) 987 { 988 ASSERT(atomic_read(&dev_replace->blocking_readers) == 0); 989 write_unlock(&dev_replace->lock); 990 } 991 992 /* inc blocking cnt and release read lock */ 993 void btrfs_dev_replace_set_lock_blocking( 994 struct btrfs_dev_replace *dev_replace) 995 { 996 /* only set blocking for read lock */ 997 atomic_inc(&dev_replace->blocking_readers); 998 read_unlock(&dev_replace->lock); 999 } 1000 1001 void btrfs_bio_counter_inc_noblocked(struct btrfs_fs_info *fs_info) 1002 { 1003 percpu_counter_inc(&fs_info->bio_counter); 1004 } 1005 1006 void btrfs_bio_counter_sub(struct btrfs_fs_info *fs_info, s64 amount) 1007 { 1008 percpu_counter_sub(&fs_info->bio_counter, amount); 1009 cond_wake_up_nomb(&fs_info->replace_wait); 1010 } 1011 1012 void btrfs_bio_counter_inc_blocked(struct btrfs_fs_info *fs_info) 1013 { 1014 while (1) { 1015 percpu_counter_inc(&fs_info->bio_counter); 1016 if (likely(!test_bit(BTRFS_FS_STATE_DEV_REPLACING, 1017 &fs_info->fs_state))) 1018 break; 1019 1020 btrfs_bio_counter_dec(fs_info); 1021 wait_event(fs_info->replace_wait, 1022 !test_bit(BTRFS_FS_STATE_DEV_REPLACING, 1023 &fs_info->fs_state)); 1024 } 1025 } 1026