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->time_started = 0; 63 dev_replace->time_stopped = 0; 64 atomic64_set(&dev_replace->num_write_errors, 0); 65 atomic64_set(&dev_replace->num_uncorrectable_read_errors, 0); 66 dev_replace->cursor_left = 0; 67 dev_replace->committed_cursor_left = 0; 68 dev_replace->cursor_left_last_write_of_item = 0; 69 dev_replace->cursor_right = 0; 70 dev_replace->srcdev = NULL; 71 dev_replace->tgtdev = NULL; 72 dev_replace->is_valid = 0; 73 dev_replace->item_needs_writeback = 0; 74 goto out; 75 } 76 slot = path->slots[0]; 77 eb = path->nodes[0]; 78 item_size = btrfs_item_size_nr(eb, slot); 79 ptr = btrfs_item_ptr(eb, slot, struct btrfs_dev_replace_item); 80 81 if (item_size != sizeof(struct btrfs_dev_replace_item)) { 82 btrfs_warn(fs_info, 83 "dev_replace entry found has unexpected size, ignore entry"); 84 goto no_valid_dev_replace_entry_found; 85 } 86 87 src_devid = btrfs_dev_replace_src_devid(eb, ptr); 88 dev_replace->cont_reading_from_srcdev_mode = 89 btrfs_dev_replace_cont_reading_from_srcdev_mode(eb, ptr); 90 dev_replace->replace_state = btrfs_dev_replace_replace_state(eb, ptr); 91 dev_replace->time_started = btrfs_dev_replace_time_started(eb, ptr); 92 dev_replace->time_stopped = 93 btrfs_dev_replace_time_stopped(eb, ptr); 94 atomic64_set(&dev_replace->num_write_errors, 95 btrfs_dev_replace_num_write_errors(eb, ptr)); 96 atomic64_set(&dev_replace->num_uncorrectable_read_errors, 97 btrfs_dev_replace_num_uncorrectable_read_errors(eb, ptr)); 98 dev_replace->cursor_left = btrfs_dev_replace_cursor_left(eb, ptr); 99 dev_replace->committed_cursor_left = dev_replace->cursor_left; 100 dev_replace->cursor_left_last_write_of_item = dev_replace->cursor_left; 101 dev_replace->cursor_right = btrfs_dev_replace_cursor_right(eb, ptr); 102 dev_replace->is_valid = 1; 103 104 dev_replace->item_needs_writeback = 0; 105 switch (dev_replace->replace_state) { 106 case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED: 107 case BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED: 108 case BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED: 109 dev_replace->srcdev = NULL; 110 dev_replace->tgtdev = NULL; 111 break; 112 case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED: 113 case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED: 114 dev_replace->srcdev = btrfs_find_device(fs_info, src_devid, 115 NULL, NULL); 116 dev_replace->tgtdev = btrfs_find_device(fs_info, 117 BTRFS_DEV_REPLACE_DEVID, 118 NULL, NULL); 119 /* 120 * allow 'btrfs dev replace_cancel' if src/tgt device is 121 * missing 122 */ 123 if (!dev_replace->srcdev && 124 !btrfs_test_opt(fs_info, DEGRADED)) { 125 ret = -EIO; 126 btrfs_warn(fs_info, 127 "cannot mount because device replace operation is ongoing and"); 128 btrfs_warn(fs_info, 129 "srcdev (devid %llu) is missing, need to run 'btrfs dev scan'?", 130 src_devid); 131 } 132 if (!dev_replace->tgtdev && 133 !btrfs_test_opt(fs_info, DEGRADED)) { 134 ret = -EIO; 135 btrfs_warn(fs_info, 136 "cannot mount because device replace operation is ongoing and"); 137 btrfs_warn(fs_info, 138 "tgtdev (devid %llu) is missing, need to run 'btrfs dev scan'?", 139 BTRFS_DEV_REPLACE_DEVID); 140 } 141 if (dev_replace->tgtdev) { 142 if (dev_replace->srcdev) { 143 dev_replace->tgtdev->total_bytes = 144 dev_replace->srcdev->total_bytes; 145 dev_replace->tgtdev->disk_total_bytes = 146 dev_replace->srcdev->disk_total_bytes; 147 dev_replace->tgtdev->commit_total_bytes = 148 dev_replace->srcdev->commit_total_bytes; 149 dev_replace->tgtdev->bytes_used = 150 dev_replace->srcdev->bytes_used; 151 dev_replace->tgtdev->commit_bytes_used = 152 dev_replace->srcdev->commit_bytes_used; 153 } 154 set_bit(BTRFS_DEV_STATE_REPLACE_TGT, 155 &dev_replace->tgtdev->dev_state); 156 157 WARN_ON(fs_info->fs_devices->rw_devices == 0); 158 dev_replace->tgtdev->io_width = fs_info->sectorsize; 159 dev_replace->tgtdev->io_align = fs_info->sectorsize; 160 dev_replace->tgtdev->sector_size = fs_info->sectorsize; 161 dev_replace->tgtdev->fs_info = fs_info; 162 set_bit(BTRFS_DEV_STATE_IN_FS_METADATA, 163 &dev_replace->tgtdev->dev_state); 164 } 165 break; 166 } 167 168 out: 169 btrfs_free_path(path); 170 return ret; 171 } 172 173 /* 174 * Initialize a new device for device replace target from a given source dev 175 * and path. 176 * 177 * Return 0 and new device in @device_out, otherwise return < 0 178 */ 179 static int btrfs_init_dev_replace_tgtdev(struct btrfs_fs_info *fs_info, 180 const char *device_path, 181 struct btrfs_device *srcdev, 182 struct btrfs_device **device_out) 183 { 184 struct btrfs_device *device; 185 struct block_device *bdev; 186 struct list_head *devices; 187 struct rcu_string *name; 188 u64 devid = BTRFS_DEV_REPLACE_DEVID; 189 int ret = 0; 190 191 *device_out = NULL; 192 if (fs_info->fs_devices->seeding) { 193 btrfs_err(fs_info, "the filesystem is a seed filesystem!"); 194 return -EINVAL; 195 } 196 197 bdev = blkdev_get_by_path(device_path, FMODE_WRITE | FMODE_EXCL, 198 fs_info->bdev_holder); 199 if (IS_ERR(bdev)) { 200 btrfs_err(fs_info, "target device %s is invalid!", device_path); 201 return PTR_ERR(bdev); 202 } 203 204 filemap_write_and_wait(bdev->bd_inode->i_mapping); 205 206 devices = &fs_info->fs_devices->devices; 207 list_for_each_entry(device, devices, dev_list) { 208 if (device->bdev == bdev) { 209 btrfs_err(fs_info, 210 "target device is in the filesystem!"); 211 ret = -EEXIST; 212 goto error; 213 } 214 } 215 216 217 if (i_size_read(bdev->bd_inode) < 218 btrfs_device_get_total_bytes(srcdev)) { 219 btrfs_err(fs_info, 220 "target device is smaller than source device!"); 221 ret = -EINVAL; 222 goto error; 223 } 224 225 226 device = btrfs_alloc_device(NULL, &devid, NULL); 227 if (IS_ERR(device)) { 228 ret = PTR_ERR(device); 229 goto error; 230 } 231 232 name = rcu_string_strdup(device_path, GFP_KERNEL); 233 if (!name) { 234 btrfs_free_device(device); 235 ret = -ENOMEM; 236 goto error; 237 } 238 rcu_assign_pointer(device->name, name); 239 240 mutex_lock(&fs_info->fs_devices->device_list_mutex); 241 set_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state); 242 device->generation = 0; 243 device->io_width = fs_info->sectorsize; 244 device->io_align = fs_info->sectorsize; 245 device->sector_size = fs_info->sectorsize; 246 device->total_bytes = btrfs_device_get_total_bytes(srcdev); 247 device->disk_total_bytes = btrfs_device_get_disk_total_bytes(srcdev); 248 device->bytes_used = btrfs_device_get_bytes_used(srcdev); 249 device->commit_total_bytes = srcdev->commit_total_bytes; 250 device->commit_bytes_used = device->bytes_used; 251 device->fs_info = fs_info; 252 device->bdev = bdev; 253 set_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state); 254 set_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state); 255 device->mode = FMODE_EXCL; 256 device->dev_stats_valid = 1; 257 set_blocksize(device->bdev, BTRFS_BDEV_BLOCKSIZE); 258 device->fs_devices = fs_info->fs_devices; 259 list_add(&device->dev_list, &fs_info->fs_devices->devices); 260 fs_info->fs_devices->num_devices++; 261 fs_info->fs_devices->open_devices++; 262 mutex_unlock(&fs_info->fs_devices->device_list_mutex); 263 264 *device_out = device; 265 return 0; 266 267 error: 268 blkdev_put(bdev, FMODE_EXCL); 269 return ret; 270 } 271 272 /* 273 * called from commit_transaction. Writes changed device replace state to 274 * disk. 275 */ 276 int btrfs_run_dev_replace(struct btrfs_trans_handle *trans, 277 struct btrfs_fs_info *fs_info) 278 { 279 int ret; 280 struct btrfs_root *dev_root = fs_info->dev_root; 281 struct btrfs_path *path; 282 struct btrfs_key key; 283 struct extent_buffer *eb; 284 struct btrfs_dev_replace_item *ptr; 285 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace; 286 287 btrfs_dev_replace_read_lock(dev_replace); 288 if (!dev_replace->is_valid || 289 !dev_replace->item_needs_writeback) { 290 btrfs_dev_replace_read_unlock(dev_replace); 291 return 0; 292 } 293 btrfs_dev_replace_read_unlock(dev_replace); 294 295 key.objectid = 0; 296 key.type = BTRFS_DEV_REPLACE_KEY; 297 key.offset = 0; 298 299 path = btrfs_alloc_path(); 300 if (!path) { 301 ret = -ENOMEM; 302 goto out; 303 } 304 ret = btrfs_search_slot(trans, dev_root, &key, path, -1, 1); 305 if (ret < 0) { 306 btrfs_warn(fs_info, 307 "error %d while searching for dev_replace item!", 308 ret); 309 goto out; 310 } 311 312 if (ret == 0 && 313 btrfs_item_size_nr(path->nodes[0], path->slots[0]) < sizeof(*ptr)) { 314 /* 315 * need to delete old one and insert a new one. 316 * Since no attempt is made to recover any old state, if the 317 * dev_replace state is 'running', the data on the target 318 * drive is lost. 319 * It would be possible to recover the state: just make sure 320 * that the beginning of the item is never changed and always 321 * contains all the essential information. Then read this 322 * minimal set of information and use it as a base for the 323 * new state. 324 */ 325 ret = btrfs_del_item(trans, dev_root, path); 326 if (ret != 0) { 327 btrfs_warn(fs_info, 328 "delete too small dev_replace item failed %d!", 329 ret); 330 goto out; 331 } 332 ret = 1; 333 } 334 335 if (ret == 1) { 336 /* need to insert a new item */ 337 btrfs_release_path(path); 338 ret = btrfs_insert_empty_item(trans, dev_root, path, 339 &key, sizeof(*ptr)); 340 if (ret < 0) { 341 btrfs_warn(fs_info, 342 "insert dev_replace item failed %d!", ret); 343 goto out; 344 } 345 } 346 347 eb = path->nodes[0]; 348 ptr = btrfs_item_ptr(eb, path->slots[0], 349 struct btrfs_dev_replace_item); 350 351 btrfs_dev_replace_write_lock(dev_replace); 352 if (dev_replace->srcdev) 353 btrfs_set_dev_replace_src_devid(eb, ptr, 354 dev_replace->srcdev->devid); 355 else 356 btrfs_set_dev_replace_src_devid(eb, ptr, (u64)-1); 357 btrfs_set_dev_replace_cont_reading_from_srcdev_mode(eb, ptr, 358 dev_replace->cont_reading_from_srcdev_mode); 359 btrfs_set_dev_replace_replace_state(eb, ptr, 360 dev_replace->replace_state); 361 btrfs_set_dev_replace_time_started(eb, ptr, dev_replace->time_started); 362 btrfs_set_dev_replace_time_stopped(eb, ptr, dev_replace->time_stopped); 363 btrfs_set_dev_replace_num_write_errors(eb, ptr, 364 atomic64_read(&dev_replace->num_write_errors)); 365 btrfs_set_dev_replace_num_uncorrectable_read_errors(eb, ptr, 366 atomic64_read(&dev_replace->num_uncorrectable_read_errors)); 367 dev_replace->cursor_left_last_write_of_item = 368 dev_replace->cursor_left; 369 btrfs_set_dev_replace_cursor_left(eb, ptr, 370 dev_replace->cursor_left_last_write_of_item); 371 btrfs_set_dev_replace_cursor_right(eb, ptr, 372 dev_replace->cursor_right); 373 dev_replace->item_needs_writeback = 0; 374 btrfs_dev_replace_write_unlock(dev_replace); 375 376 btrfs_mark_buffer_dirty(eb); 377 378 out: 379 btrfs_free_path(path); 380 381 return ret; 382 } 383 384 static char* btrfs_dev_name(struct btrfs_device *device) 385 { 386 if (!device || test_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state)) 387 return "<missing disk>"; 388 else 389 return rcu_str_deref(device->name); 390 } 391 392 static int btrfs_dev_replace_start(struct btrfs_fs_info *fs_info, 393 const char *tgtdev_name, u64 srcdevid, const char *srcdev_name, 394 int read_src) 395 { 396 struct btrfs_root *root = fs_info->dev_root; 397 struct btrfs_trans_handle *trans; 398 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace; 399 int ret; 400 struct btrfs_device *tgt_device = NULL; 401 struct btrfs_device *src_device = NULL; 402 bool need_unlock; 403 404 src_device = btrfs_find_device_by_devspec(fs_info, srcdevid, 405 srcdev_name); 406 if (IS_ERR(src_device)) 407 return PTR_ERR(src_device); 408 409 if (btrfs_pinned_by_swapfile(fs_info, src_device)) { 410 btrfs_warn_in_rcu(fs_info, 411 "cannot replace device %s (devid %llu) due to active swapfile", 412 btrfs_dev_name(src_device), src_device->devid); 413 return -ETXTBSY; 414 } 415 416 ret = btrfs_init_dev_replace_tgtdev(fs_info, tgtdev_name, 417 src_device, &tgt_device); 418 if (ret) 419 return ret; 420 421 /* 422 * Here we commit the transaction to make sure commit_total_bytes 423 * of all the devices are updated. 424 */ 425 trans = btrfs_attach_transaction(root); 426 if (!IS_ERR(trans)) { 427 ret = btrfs_commit_transaction(trans); 428 if (ret) 429 return ret; 430 } else if (PTR_ERR(trans) != -ENOENT) { 431 return PTR_ERR(trans); 432 } 433 434 need_unlock = true; 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 need_unlock = false; 475 476 ret = btrfs_sysfs_add_device_link(tgt_device->fs_devices, tgt_device); 477 if (ret) 478 btrfs_err(fs_info, "kobj add dev failed %d", ret); 479 480 btrfs_wait_ordered_roots(fs_info, U64_MAX, 0, (u64)-1); 481 482 /* force writing the updated state information to disk */ 483 trans = btrfs_start_transaction(root, 0); 484 if (IS_ERR(trans)) { 485 ret = PTR_ERR(trans); 486 need_unlock = true; 487 btrfs_dev_replace_write_lock(dev_replace); 488 dev_replace->replace_state = 489 BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED; 490 dev_replace->srcdev = NULL; 491 dev_replace->tgtdev = NULL; 492 goto leave; 493 } 494 495 ret = btrfs_commit_transaction(trans); 496 WARN_ON(ret); 497 498 /* the disk copy procedure reuses the scrub code */ 499 ret = btrfs_scrub_dev(fs_info, src_device->devid, 0, 500 btrfs_device_get_total_bytes(src_device), 501 &dev_replace->scrub_progress, 0, 1); 502 503 ret = btrfs_dev_replace_finishing(fs_info, ret); 504 if (ret == -EINPROGRESS) { 505 ret = BTRFS_IOCTL_DEV_REPLACE_RESULT_SCRUB_INPROGRESS; 506 } else if (ret != -ECANCELED) { 507 WARN_ON(ret); 508 } 509 510 return ret; 511 512 leave: 513 if (need_unlock) 514 btrfs_dev_replace_write_unlock(dev_replace); 515 btrfs_destroy_dev_replace_tgtdev(tgt_device); 516 return ret; 517 } 518 519 int btrfs_dev_replace_by_ioctl(struct btrfs_fs_info *fs_info, 520 struct btrfs_ioctl_dev_replace_args *args) 521 { 522 int ret; 523 524 switch (args->start.cont_reading_from_srcdev_mode) { 525 case BTRFS_IOCTL_DEV_REPLACE_CONT_READING_FROM_SRCDEV_MODE_ALWAYS: 526 case BTRFS_IOCTL_DEV_REPLACE_CONT_READING_FROM_SRCDEV_MODE_AVOID: 527 break; 528 default: 529 return -EINVAL; 530 } 531 532 if ((args->start.srcdevid == 0 && args->start.srcdev_name[0] == '\0') || 533 args->start.tgtdev_name[0] == '\0') 534 return -EINVAL; 535 536 ret = btrfs_dev_replace_start(fs_info, args->start.tgtdev_name, 537 args->start.srcdevid, 538 args->start.srcdev_name, 539 args->start.cont_reading_from_srcdev_mode); 540 args->result = ret; 541 /* don't warn if EINPROGRESS, someone else might be running scrub */ 542 if (ret == BTRFS_IOCTL_DEV_REPLACE_RESULT_SCRUB_INPROGRESS || 543 ret == BTRFS_IOCTL_DEV_REPLACE_RESULT_NO_ERROR) 544 return 0; 545 546 return ret; 547 } 548 549 /* 550 * blocked until all in-flight bios operations are finished. 551 */ 552 static void btrfs_rm_dev_replace_blocked(struct btrfs_fs_info *fs_info) 553 { 554 set_bit(BTRFS_FS_STATE_DEV_REPLACING, &fs_info->fs_state); 555 wait_event(fs_info->dev_replace.replace_wait, !percpu_counter_sum( 556 &fs_info->dev_replace.bio_counter)); 557 } 558 559 /* 560 * we have removed target device, it is safe to allow new bios request. 561 */ 562 static void btrfs_rm_dev_replace_unblocked(struct btrfs_fs_info *fs_info) 563 { 564 clear_bit(BTRFS_FS_STATE_DEV_REPLACING, &fs_info->fs_state); 565 wake_up(&fs_info->dev_replace.replace_wait); 566 } 567 568 static int btrfs_dev_replace_finishing(struct btrfs_fs_info *fs_info, 569 int scrub_ret) 570 { 571 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace; 572 struct btrfs_device *tgt_device; 573 struct btrfs_device *src_device; 574 struct btrfs_root *root = fs_info->tree_root; 575 u8 uuid_tmp[BTRFS_UUID_SIZE]; 576 struct btrfs_trans_handle *trans; 577 int ret = 0; 578 579 /* don't allow cancel or unmount to disturb the finishing procedure */ 580 mutex_lock(&dev_replace->lock_finishing_cancel_unmount); 581 582 btrfs_dev_replace_read_lock(dev_replace); 583 /* was the operation canceled, or is it finished? */ 584 if (dev_replace->replace_state != 585 BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED) { 586 btrfs_dev_replace_read_unlock(dev_replace); 587 mutex_unlock(&dev_replace->lock_finishing_cancel_unmount); 588 return 0; 589 } 590 591 tgt_device = dev_replace->tgtdev; 592 src_device = dev_replace->srcdev; 593 btrfs_dev_replace_read_unlock(dev_replace); 594 595 /* 596 * flush all outstanding I/O and inode extent mappings before the 597 * copy operation is declared as being finished 598 */ 599 ret = btrfs_start_delalloc_roots(fs_info, -1); 600 if (ret) { 601 mutex_unlock(&dev_replace->lock_finishing_cancel_unmount); 602 return ret; 603 } 604 btrfs_wait_ordered_roots(fs_info, U64_MAX, 0, (u64)-1); 605 606 trans = btrfs_start_transaction(root, 0); 607 if (IS_ERR(trans)) { 608 mutex_unlock(&dev_replace->lock_finishing_cancel_unmount); 609 return PTR_ERR(trans); 610 } 611 ret = btrfs_commit_transaction(trans); 612 WARN_ON(ret); 613 614 /* keep away write_all_supers() during the finishing procedure */ 615 mutex_lock(&fs_info->fs_devices->device_list_mutex); 616 mutex_lock(&fs_info->chunk_mutex); 617 btrfs_dev_replace_write_lock(dev_replace); 618 dev_replace->replace_state = 619 scrub_ret ? BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED 620 : BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED; 621 dev_replace->tgtdev = NULL; 622 dev_replace->srcdev = NULL; 623 dev_replace->time_stopped = ktime_get_real_seconds(); 624 dev_replace->item_needs_writeback = 1; 625 626 /* replace old device with new one in mapping tree */ 627 if (!scrub_ret) { 628 btrfs_dev_replace_update_device_in_mapping_tree(fs_info, 629 src_device, 630 tgt_device); 631 } else { 632 if (scrub_ret != -ECANCELED) 633 btrfs_err_in_rcu(fs_info, 634 "btrfs_scrub_dev(%s, %llu, %s) failed %d", 635 btrfs_dev_name(src_device), 636 src_device->devid, 637 rcu_str_deref(tgt_device->name), scrub_ret); 638 btrfs_dev_replace_write_unlock(dev_replace); 639 mutex_unlock(&fs_info->chunk_mutex); 640 mutex_unlock(&fs_info->fs_devices->device_list_mutex); 641 btrfs_rm_dev_replace_blocked(fs_info); 642 if (tgt_device) 643 btrfs_destroy_dev_replace_tgtdev(tgt_device); 644 btrfs_rm_dev_replace_unblocked(fs_info); 645 mutex_unlock(&dev_replace->lock_finishing_cancel_unmount); 646 647 return scrub_ret; 648 } 649 650 btrfs_info_in_rcu(fs_info, 651 "dev_replace from %s (devid %llu) to %s finished", 652 btrfs_dev_name(src_device), 653 src_device->devid, 654 rcu_str_deref(tgt_device->name)); 655 clear_bit(BTRFS_DEV_STATE_REPLACE_TGT, &tgt_device->dev_state); 656 tgt_device->devid = src_device->devid; 657 src_device->devid = BTRFS_DEV_REPLACE_DEVID; 658 memcpy(uuid_tmp, tgt_device->uuid, sizeof(uuid_tmp)); 659 memcpy(tgt_device->uuid, src_device->uuid, sizeof(tgt_device->uuid)); 660 memcpy(src_device->uuid, uuid_tmp, sizeof(src_device->uuid)); 661 btrfs_device_set_total_bytes(tgt_device, src_device->total_bytes); 662 btrfs_device_set_disk_total_bytes(tgt_device, 663 src_device->disk_total_bytes); 664 btrfs_device_set_bytes_used(tgt_device, src_device->bytes_used); 665 ASSERT(list_empty(&src_device->resized_list)); 666 tgt_device->commit_total_bytes = src_device->commit_total_bytes; 667 tgt_device->commit_bytes_used = src_device->bytes_used; 668 669 btrfs_assign_next_active_device(src_device, tgt_device); 670 671 list_add(&tgt_device->dev_alloc_list, &fs_info->fs_devices->alloc_list); 672 fs_info->fs_devices->rw_devices++; 673 674 btrfs_dev_replace_write_unlock(dev_replace); 675 676 btrfs_rm_dev_replace_blocked(fs_info); 677 678 btrfs_rm_dev_replace_remove_srcdev(src_device); 679 680 btrfs_rm_dev_replace_unblocked(fs_info); 681 682 /* 683 * Increment dev_stats_ccnt so that btrfs_run_dev_stats() will 684 * update on-disk dev stats value during commit transaction 685 */ 686 atomic_inc(&tgt_device->dev_stats_ccnt); 687 688 /* 689 * this is again a consistent state where no dev_replace procedure 690 * is running, the target device is part of the filesystem, the 691 * source device is not part of the filesystem anymore and its 1st 692 * superblock is scratched out so that it is no longer marked to 693 * belong to this filesystem. 694 */ 695 mutex_unlock(&fs_info->chunk_mutex); 696 mutex_unlock(&fs_info->fs_devices->device_list_mutex); 697 698 /* replace the sysfs entry */ 699 btrfs_sysfs_rm_device_link(fs_info->fs_devices, src_device); 700 btrfs_rm_dev_replace_free_srcdev(fs_info, src_device); 701 702 /* write back the superblocks */ 703 trans = btrfs_start_transaction(root, 0); 704 if (!IS_ERR(trans)) 705 btrfs_commit_transaction(trans); 706 707 mutex_unlock(&dev_replace->lock_finishing_cancel_unmount); 708 709 return 0; 710 } 711 712 static void btrfs_dev_replace_update_device_in_mapping_tree( 713 struct btrfs_fs_info *fs_info, 714 struct btrfs_device *srcdev, 715 struct btrfs_device *tgtdev) 716 { 717 struct extent_map_tree *em_tree = &fs_info->mapping_tree.map_tree; 718 struct extent_map *em; 719 struct map_lookup *map; 720 u64 start = 0; 721 int i; 722 723 write_lock(&em_tree->lock); 724 do { 725 em = lookup_extent_mapping(em_tree, start, (u64)-1); 726 if (!em) 727 break; 728 map = em->map_lookup; 729 for (i = 0; i < map->num_stripes; i++) 730 if (srcdev == map->stripes[i].dev) 731 map->stripes[i].dev = tgtdev; 732 start = em->start + em->len; 733 free_extent_map(em); 734 } while (start); 735 write_unlock(&em_tree->lock); 736 } 737 738 /* 739 * Read progress of device replace status according to the state and last 740 * stored position. The value format is the same as for 741 * btrfs_dev_replace::progress_1000 742 */ 743 static u64 btrfs_dev_replace_progress(struct btrfs_fs_info *fs_info) 744 { 745 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace; 746 u64 ret = 0; 747 748 switch (dev_replace->replace_state) { 749 case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED: 750 case BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED: 751 ret = 0; 752 break; 753 case BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED: 754 ret = 1000; 755 break; 756 case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED: 757 case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED: 758 ret = div64_u64(dev_replace->cursor_left, 759 div_u64(btrfs_device_get_total_bytes( 760 dev_replace->srcdev), 1000)); 761 break; 762 } 763 764 return ret; 765 } 766 767 void btrfs_dev_replace_status(struct btrfs_fs_info *fs_info, 768 struct btrfs_ioctl_dev_replace_args *args) 769 { 770 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace; 771 772 btrfs_dev_replace_read_lock(dev_replace); 773 /* even if !dev_replace_is_valid, the values are good enough for 774 * the replace_status ioctl */ 775 args->result = BTRFS_IOCTL_DEV_REPLACE_RESULT_NO_ERROR; 776 args->status.replace_state = dev_replace->replace_state; 777 args->status.time_started = dev_replace->time_started; 778 args->status.time_stopped = dev_replace->time_stopped; 779 args->status.num_write_errors = 780 atomic64_read(&dev_replace->num_write_errors); 781 args->status.num_uncorrectable_read_errors = 782 atomic64_read(&dev_replace->num_uncorrectable_read_errors); 783 args->status.progress_1000 = btrfs_dev_replace_progress(fs_info); 784 btrfs_dev_replace_read_unlock(dev_replace); 785 } 786 787 int btrfs_dev_replace_cancel(struct btrfs_fs_info *fs_info) 788 { 789 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace; 790 struct btrfs_device *tgt_device = NULL; 791 struct btrfs_device *src_device = NULL; 792 struct btrfs_trans_handle *trans; 793 struct btrfs_root *root = fs_info->tree_root; 794 int result; 795 int ret; 796 797 if (sb_rdonly(fs_info->sb)) 798 return -EROFS; 799 800 mutex_lock(&dev_replace->lock_finishing_cancel_unmount); 801 btrfs_dev_replace_write_lock(dev_replace); 802 switch (dev_replace->replace_state) { 803 case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED: 804 case BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED: 805 case BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED: 806 result = BTRFS_IOCTL_DEV_REPLACE_RESULT_NOT_STARTED; 807 btrfs_dev_replace_write_unlock(dev_replace); 808 break; 809 case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED: 810 tgt_device = dev_replace->tgtdev; 811 src_device = dev_replace->srcdev; 812 btrfs_dev_replace_write_unlock(dev_replace); 813 ret = btrfs_scrub_cancel(fs_info); 814 if (ret < 0) { 815 result = BTRFS_IOCTL_DEV_REPLACE_RESULT_NOT_STARTED; 816 } else { 817 result = BTRFS_IOCTL_DEV_REPLACE_RESULT_NO_ERROR; 818 /* 819 * btrfs_dev_replace_finishing() will handle the 820 * cleanup part 821 */ 822 btrfs_info_in_rcu(fs_info, 823 "dev_replace from %s (devid %llu) to %s canceled", 824 btrfs_dev_name(src_device), src_device->devid, 825 btrfs_dev_name(tgt_device)); 826 } 827 break; 828 case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED: 829 /* 830 * Scrub doing the replace isn't running so we need to do the 831 * cleanup step of btrfs_dev_replace_finishing() here 832 */ 833 result = BTRFS_IOCTL_DEV_REPLACE_RESULT_NO_ERROR; 834 tgt_device = dev_replace->tgtdev; 835 src_device = dev_replace->srcdev; 836 dev_replace->tgtdev = NULL; 837 dev_replace->srcdev = NULL; 838 dev_replace->replace_state = 839 BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED; 840 dev_replace->time_stopped = ktime_get_real_seconds(); 841 dev_replace->item_needs_writeback = 1; 842 843 btrfs_dev_replace_write_unlock(dev_replace); 844 845 /* Scrub for replace must not be running in suspended state */ 846 ret = btrfs_scrub_cancel(fs_info); 847 ASSERT(ret != -ENOTCONN); 848 849 trans = btrfs_start_transaction(root, 0); 850 if (IS_ERR(trans)) { 851 mutex_unlock(&dev_replace->lock_finishing_cancel_unmount); 852 return PTR_ERR(trans); 853 } 854 ret = btrfs_commit_transaction(trans); 855 WARN_ON(ret); 856 857 btrfs_info_in_rcu(fs_info, 858 "suspended dev_replace from %s (devid %llu) to %s canceled", 859 btrfs_dev_name(src_device), src_device->devid, 860 btrfs_dev_name(tgt_device)); 861 862 if (tgt_device) 863 btrfs_destroy_dev_replace_tgtdev(tgt_device); 864 break; 865 default: 866 result = -EINVAL; 867 } 868 869 mutex_unlock(&dev_replace->lock_finishing_cancel_unmount); 870 return result; 871 } 872 873 void btrfs_dev_replace_suspend_for_unmount(struct btrfs_fs_info *fs_info) 874 { 875 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace; 876 877 mutex_lock(&dev_replace->lock_finishing_cancel_unmount); 878 btrfs_dev_replace_write_lock(dev_replace); 879 switch (dev_replace->replace_state) { 880 case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED: 881 case BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED: 882 case BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED: 883 case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED: 884 break; 885 case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED: 886 dev_replace->replace_state = 887 BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED; 888 dev_replace->time_stopped = ktime_get_real_seconds(); 889 dev_replace->item_needs_writeback = 1; 890 btrfs_info(fs_info, "suspending dev_replace for unmount"); 891 break; 892 } 893 894 btrfs_dev_replace_write_unlock(dev_replace); 895 mutex_unlock(&dev_replace->lock_finishing_cancel_unmount); 896 } 897 898 /* resume dev_replace procedure that was interrupted by unmount */ 899 int btrfs_resume_dev_replace_async(struct btrfs_fs_info *fs_info) 900 { 901 struct task_struct *task; 902 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace; 903 904 btrfs_dev_replace_write_lock(dev_replace); 905 switch (dev_replace->replace_state) { 906 case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED: 907 case BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED: 908 case BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED: 909 btrfs_dev_replace_write_unlock(dev_replace); 910 return 0; 911 case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED: 912 break; 913 case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED: 914 dev_replace->replace_state = 915 BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED; 916 break; 917 } 918 if (!dev_replace->tgtdev || !dev_replace->tgtdev->bdev) { 919 btrfs_info(fs_info, 920 "cannot continue dev_replace, tgtdev is missing"); 921 btrfs_info(fs_info, 922 "you may cancel the operation after 'mount -o degraded'"); 923 dev_replace->replace_state = 924 BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED; 925 btrfs_dev_replace_write_unlock(dev_replace); 926 return 0; 927 } 928 btrfs_dev_replace_write_unlock(dev_replace); 929 930 /* 931 * This could collide with a paused balance, but the exclusive op logic 932 * should never allow both to start and pause. We don't want to allow 933 * dev-replace to start anyway. 934 */ 935 if (test_and_set_bit(BTRFS_FS_EXCL_OP, &fs_info->flags)) { 936 btrfs_dev_replace_write_lock(dev_replace); 937 dev_replace->replace_state = 938 BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED; 939 btrfs_dev_replace_write_unlock(dev_replace); 940 btrfs_info(fs_info, 941 "cannot resume dev-replace, other exclusive operation running"); 942 return 0; 943 } 944 945 task = kthread_run(btrfs_dev_replace_kthread, fs_info, "btrfs-devrepl"); 946 return PTR_ERR_OR_ZERO(task); 947 } 948 949 static int btrfs_dev_replace_kthread(void *data) 950 { 951 struct btrfs_fs_info *fs_info = data; 952 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace; 953 u64 progress; 954 int ret; 955 956 progress = btrfs_dev_replace_progress(fs_info); 957 progress = div_u64(progress, 10); 958 btrfs_info_in_rcu(fs_info, 959 "continuing dev_replace from %s (devid %llu) to target %s @%u%%", 960 btrfs_dev_name(dev_replace->srcdev), 961 dev_replace->srcdev->devid, 962 btrfs_dev_name(dev_replace->tgtdev), 963 (unsigned int)progress); 964 965 ret = btrfs_scrub_dev(fs_info, dev_replace->srcdev->devid, 966 dev_replace->committed_cursor_left, 967 btrfs_device_get_total_bytes(dev_replace->srcdev), 968 &dev_replace->scrub_progress, 0, 1); 969 ret = btrfs_dev_replace_finishing(fs_info, ret); 970 WARN_ON(ret && ret != -ECANCELED); 971 972 clear_bit(BTRFS_FS_EXCL_OP, &fs_info->flags); 973 return 0; 974 } 975 976 int btrfs_dev_replace_is_ongoing(struct btrfs_dev_replace *dev_replace) 977 { 978 if (!dev_replace->is_valid) 979 return 0; 980 981 switch (dev_replace->replace_state) { 982 case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED: 983 case BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED: 984 case BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED: 985 return 0; 986 case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED: 987 case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED: 988 /* 989 * return true even if tgtdev is missing (this is 990 * something that can happen if the dev_replace 991 * procedure is suspended by an umount and then 992 * the tgtdev is missing (or "btrfs dev scan") was 993 * not called and the the filesystem is remounted 994 * in degraded state. This does not stop the 995 * dev_replace procedure. It needs to be canceled 996 * manually if the cancellation is wanted. 997 */ 998 break; 999 } 1000 return 1; 1001 } 1002 1003 void btrfs_dev_replace_read_lock(struct btrfs_dev_replace *dev_replace) 1004 { 1005 down_read(&dev_replace->rwsem); 1006 } 1007 1008 void btrfs_dev_replace_read_unlock(struct btrfs_dev_replace *dev_replace) 1009 { 1010 up_read(&dev_replace->rwsem); 1011 } 1012 1013 void btrfs_dev_replace_write_lock(struct btrfs_dev_replace *dev_replace) 1014 { 1015 down_write(&dev_replace->rwsem); 1016 } 1017 1018 void btrfs_dev_replace_write_unlock(struct btrfs_dev_replace *dev_replace) 1019 { 1020 up_write(&dev_replace->rwsem); 1021 } 1022 1023 void btrfs_bio_counter_inc_noblocked(struct btrfs_fs_info *fs_info) 1024 { 1025 percpu_counter_inc(&fs_info->dev_replace.bio_counter); 1026 } 1027 1028 void btrfs_bio_counter_sub(struct btrfs_fs_info *fs_info, s64 amount) 1029 { 1030 percpu_counter_sub(&fs_info->dev_replace.bio_counter, amount); 1031 cond_wake_up_nomb(&fs_info->dev_replace.replace_wait); 1032 } 1033 1034 void btrfs_bio_counter_inc_blocked(struct btrfs_fs_info *fs_info) 1035 { 1036 while (1) { 1037 percpu_counter_inc(&fs_info->dev_replace.bio_counter); 1038 if (likely(!test_bit(BTRFS_FS_STATE_DEV_REPLACING, 1039 &fs_info->fs_state))) 1040 break; 1041 1042 btrfs_bio_counter_dec(fs_info); 1043 wait_event(fs_info->dev_replace.replace_wait, 1044 !test_bit(BTRFS_FS_STATE_DEV_REPLACING, 1045 &fs_info->fs_state)); 1046 } 1047 } 1048