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 { 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 = 0; 544 545 return ret; 546 } 547 548 /* 549 * blocked until all in-flight bios operations are finished. 550 */ 551 static void btrfs_rm_dev_replace_blocked(struct btrfs_fs_info *fs_info) 552 { 553 set_bit(BTRFS_FS_STATE_DEV_REPLACING, &fs_info->fs_state); 554 wait_event(fs_info->dev_replace.replace_wait, !percpu_counter_sum( 555 &fs_info->dev_replace.bio_counter)); 556 } 557 558 /* 559 * we have removed target device, it is safe to allow new bios request. 560 */ 561 static void btrfs_rm_dev_replace_unblocked(struct btrfs_fs_info *fs_info) 562 { 563 clear_bit(BTRFS_FS_STATE_DEV_REPLACING, &fs_info->fs_state); 564 wake_up(&fs_info->dev_replace.replace_wait); 565 } 566 567 static int btrfs_dev_replace_finishing(struct btrfs_fs_info *fs_info, 568 int scrub_ret) 569 { 570 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace; 571 struct btrfs_device *tgt_device; 572 struct btrfs_device *src_device; 573 struct btrfs_root *root = fs_info->tree_root; 574 u8 uuid_tmp[BTRFS_UUID_SIZE]; 575 struct btrfs_trans_handle *trans; 576 int ret = 0; 577 578 /* don't allow cancel or unmount to disturb the finishing procedure */ 579 mutex_lock(&dev_replace->lock_finishing_cancel_unmount); 580 581 btrfs_dev_replace_read_lock(dev_replace); 582 /* was the operation canceled, or is it finished? */ 583 if (dev_replace->replace_state != 584 BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED) { 585 btrfs_dev_replace_read_unlock(dev_replace); 586 mutex_unlock(&dev_replace->lock_finishing_cancel_unmount); 587 return 0; 588 } 589 590 tgt_device = dev_replace->tgtdev; 591 src_device = dev_replace->srcdev; 592 btrfs_dev_replace_read_unlock(dev_replace); 593 594 /* 595 * flush all outstanding I/O and inode extent mappings before the 596 * copy operation is declared as being finished 597 */ 598 ret = btrfs_start_delalloc_roots(fs_info, -1); 599 if (ret) { 600 mutex_unlock(&dev_replace->lock_finishing_cancel_unmount); 601 return ret; 602 } 603 btrfs_wait_ordered_roots(fs_info, U64_MAX, 0, (u64)-1); 604 605 trans = btrfs_start_transaction(root, 0); 606 if (IS_ERR(trans)) { 607 mutex_unlock(&dev_replace->lock_finishing_cancel_unmount); 608 return PTR_ERR(trans); 609 } 610 ret = btrfs_commit_transaction(trans); 611 WARN_ON(ret); 612 613 /* keep away write_all_supers() during the finishing procedure */ 614 mutex_lock(&fs_info->fs_devices->device_list_mutex); 615 mutex_lock(&fs_info->chunk_mutex); 616 btrfs_dev_replace_write_lock(dev_replace); 617 dev_replace->replace_state = 618 scrub_ret ? BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED 619 : BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED; 620 dev_replace->tgtdev = NULL; 621 dev_replace->srcdev = NULL; 622 dev_replace->time_stopped = ktime_get_real_seconds(); 623 dev_replace->item_needs_writeback = 1; 624 625 /* replace old device with new one in mapping tree */ 626 if (!scrub_ret) { 627 btrfs_dev_replace_update_device_in_mapping_tree(fs_info, 628 src_device, 629 tgt_device); 630 } else { 631 btrfs_err_in_rcu(fs_info, 632 "btrfs_scrub_dev(%s, %llu, %s) failed %d", 633 btrfs_dev_name(src_device), 634 src_device->devid, 635 rcu_str_deref(tgt_device->name), scrub_ret); 636 btrfs_dev_replace_write_unlock(dev_replace); 637 mutex_unlock(&fs_info->chunk_mutex); 638 mutex_unlock(&fs_info->fs_devices->device_list_mutex); 639 btrfs_rm_dev_replace_blocked(fs_info); 640 if (tgt_device) 641 btrfs_destroy_dev_replace_tgtdev(tgt_device); 642 btrfs_rm_dev_replace_unblocked(fs_info); 643 mutex_unlock(&dev_replace->lock_finishing_cancel_unmount); 644 645 return scrub_ret; 646 } 647 648 btrfs_info_in_rcu(fs_info, 649 "dev_replace from %s (devid %llu) to %s finished", 650 btrfs_dev_name(src_device), 651 src_device->devid, 652 rcu_str_deref(tgt_device->name)); 653 clear_bit(BTRFS_DEV_STATE_REPLACE_TGT, &tgt_device->dev_state); 654 tgt_device->devid = src_device->devid; 655 src_device->devid = BTRFS_DEV_REPLACE_DEVID; 656 memcpy(uuid_tmp, tgt_device->uuid, sizeof(uuid_tmp)); 657 memcpy(tgt_device->uuid, src_device->uuid, sizeof(tgt_device->uuid)); 658 memcpy(src_device->uuid, uuid_tmp, sizeof(src_device->uuid)); 659 btrfs_device_set_total_bytes(tgt_device, src_device->total_bytes); 660 btrfs_device_set_disk_total_bytes(tgt_device, 661 src_device->disk_total_bytes); 662 btrfs_device_set_bytes_used(tgt_device, src_device->bytes_used); 663 ASSERT(list_empty(&src_device->resized_list)); 664 tgt_device->commit_total_bytes = src_device->commit_total_bytes; 665 tgt_device->commit_bytes_used = src_device->bytes_used; 666 667 btrfs_assign_next_active_device(src_device, tgt_device); 668 669 list_add(&tgt_device->dev_alloc_list, &fs_info->fs_devices->alloc_list); 670 fs_info->fs_devices->rw_devices++; 671 672 btrfs_dev_replace_write_unlock(dev_replace); 673 674 btrfs_rm_dev_replace_blocked(fs_info); 675 676 btrfs_rm_dev_replace_remove_srcdev(src_device); 677 678 btrfs_rm_dev_replace_unblocked(fs_info); 679 680 /* 681 * Increment dev_stats_ccnt so that btrfs_run_dev_stats() will 682 * update on-disk dev stats value during commit transaction 683 */ 684 atomic_inc(&tgt_device->dev_stats_ccnt); 685 686 /* 687 * this is again a consistent state where no dev_replace procedure 688 * is running, the target device is part of the filesystem, the 689 * source device is not part of the filesystem anymore and its 1st 690 * superblock is scratched out so that it is no longer marked to 691 * belong to this filesystem. 692 */ 693 mutex_unlock(&fs_info->chunk_mutex); 694 mutex_unlock(&fs_info->fs_devices->device_list_mutex); 695 696 /* replace the sysfs entry */ 697 btrfs_sysfs_rm_device_link(fs_info->fs_devices, src_device); 698 btrfs_rm_dev_replace_free_srcdev(fs_info, src_device); 699 700 /* write back the superblocks */ 701 trans = btrfs_start_transaction(root, 0); 702 if (!IS_ERR(trans)) 703 btrfs_commit_transaction(trans); 704 705 mutex_unlock(&dev_replace->lock_finishing_cancel_unmount); 706 707 return 0; 708 } 709 710 static void btrfs_dev_replace_update_device_in_mapping_tree( 711 struct btrfs_fs_info *fs_info, 712 struct btrfs_device *srcdev, 713 struct btrfs_device *tgtdev) 714 { 715 struct extent_map_tree *em_tree = &fs_info->mapping_tree.map_tree; 716 struct extent_map *em; 717 struct map_lookup *map; 718 u64 start = 0; 719 int i; 720 721 write_lock(&em_tree->lock); 722 do { 723 em = lookup_extent_mapping(em_tree, start, (u64)-1); 724 if (!em) 725 break; 726 map = em->map_lookup; 727 for (i = 0; i < map->num_stripes; i++) 728 if (srcdev == map->stripes[i].dev) 729 map->stripes[i].dev = tgtdev; 730 start = em->start + em->len; 731 free_extent_map(em); 732 } while (start); 733 write_unlock(&em_tree->lock); 734 } 735 736 /* 737 * Read progress of device replace status according to the state and last 738 * stored position. The value format is the same as for 739 * btrfs_dev_replace::progress_1000 740 */ 741 static u64 btrfs_dev_replace_progress(struct btrfs_fs_info *fs_info) 742 { 743 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace; 744 u64 ret = 0; 745 746 switch (dev_replace->replace_state) { 747 case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED: 748 case BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED: 749 ret = 0; 750 break; 751 case BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED: 752 ret = 1000; 753 break; 754 case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED: 755 case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED: 756 ret = div64_u64(dev_replace->cursor_left, 757 div_u64(btrfs_device_get_total_bytes( 758 dev_replace->srcdev), 1000)); 759 break; 760 } 761 762 return ret; 763 } 764 765 void btrfs_dev_replace_status(struct btrfs_fs_info *fs_info, 766 struct btrfs_ioctl_dev_replace_args *args) 767 { 768 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace; 769 770 btrfs_dev_replace_read_lock(dev_replace); 771 /* even if !dev_replace_is_valid, the values are good enough for 772 * the replace_status ioctl */ 773 args->result = BTRFS_IOCTL_DEV_REPLACE_RESULT_NO_ERROR; 774 args->status.replace_state = dev_replace->replace_state; 775 args->status.time_started = dev_replace->time_started; 776 args->status.time_stopped = dev_replace->time_stopped; 777 args->status.num_write_errors = 778 atomic64_read(&dev_replace->num_write_errors); 779 args->status.num_uncorrectable_read_errors = 780 atomic64_read(&dev_replace->num_uncorrectable_read_errors); 781 args->status.progress_1000 = btrfs_dev_replace_progress(fs_info); 782 btrfs_dev_replace_read_unlock(dev_replace); 783 } 784 785 int btrfs_dev_replace_cancel(struct btrfs_fs_info *fs_info) 786 { 787 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace; 788 struct btrfs_device *tgt_device = NULL; 789 struct btrfs_device *src_device = NULL; 790 struct btrfs_trans_handle *trans; 791 struct btrfs_root *root = fs_info->tree_root; 792 int result; 793 int ret; 794 795 if (sb_rdonly(fs_info->sb)) 796 return -EROFS; 797 798 mutex_lock(&dev_replace->lock_finishing_cancel_unmount); 799 btrfs_dev_replace_write_lock(dev_replace); 800 switch (dev_replace->replace_state) { 801 case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED: 802 case BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED: 803 case BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED: 804 result = BTRFS_IOCTL_DEV_REPLACE_RESULT_NOT_STARTED; 805 btrfs_dev_replace_write_unlock(dev_replace); 806 break; 807 case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED: 808 result = BTRFS_IOCTL_DEV_REPLACE_RESULT_NO_ERROR; 809 tgt_device = dev_replace->tgtdev; 810 src_device = dev_replace->srcdev; 811 btrfs_dev_replace_write_unlock(dev_replace); 812 btrfs_scrub_cancel(fs_info); 813 /* btrfs_dev_replace_finishing() will handle the cleanup part */ 814 btrfs_info_in_rcu(fs_info, 815 "dev_replace from %s (devid %llu) to %s canceled", 816 btrfs_dev_name(src_device), src_device->devid, 817 btrfs_dev_name(tgt_device)); 818 break; 819 case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED: 820 /* 821 * Scrub doing the replace isn't running so we need to do the 822 * cleanup step of btrfs_dev_replace_finishing() here 823 */ 824 result = BTRFS_IOCTL_DEV_REPLACE_RESULT_NO_ERROR; 825 tgt_device = dev_replace->tgtdev; 826 src_device = dev_replace->srcdev; 827 dev_replace->tgtdev = NULL; 828 dev_replace->srcdev = NULL; 829 dev_replace->replace_state = 830 BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED; 831 dev_replace->time_stopped = ktime_get_real_seconds(); 832 dev_replace->item_needs_writeback = 1; 833 834 btrfs_dev_replace_write_unlock(dev_replace); 835 836 btrfs_scrub_cancel(fs_info); 837 838 trans = btrfs_start_transaction(root, 0); 839 if (IS_ERR(trans)) { 840 mutex_unlock(&dev_replace->lock_finishing_cancel_unmount); 841 return PTR_ERR(trans); 842 } 843 ret = btrfs_commit_transaction(trans); 844 WARN_ON(ret); 845 846 btrfs_info_in_rcu(fs_info, 847 "suspended dev_replace from %s (devid %llu) to %s canceled", 848 btrfs_dev_name(src_device), src_device->devid, 849 btrfs_dev_name(tgt_device)); 850 851 if (tgt_device) 852 btrfs_destroy_dev_replace_tgtdev(tgt_device); 853 break; 854 default: 855 result = -EINVAL; 856 } 857 858 mutex_unlock(&dev_replace->lock_finishing_cancel_unmount); 859 return result; 860 } 861 862 void btrfs_dev_replace_suspend_for_unmount(struct btrfs_fs_info *fs_info) 863 { 864 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace; 865 866 mutex_lock(&dev_replace->lock_finishing_cancel_unmount); 867 btrfs_dev_replace_write_lock(dev_replace); 868 switch (dev_replace->replace_state) { 869 case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED: 870 case BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED: 871 case BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED: 872 case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED: 873 break; 874 case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED: 875 dev_replace->replace_state = 876 BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED; 877 dev_replace->time_stopped = ktime_get_real_seconds(); 878 dev_replace->item_needs_writeback = 1; 879 btrfs_info(fs_info, "suspending dev_replace for unmount"); 880 break; 881 } 882 883 btrfs_dev_replace_write_unlock(dev_replace); 884 mutex_unlock(&dev_replace->lock_finishing_cancel_unmount); 885 } 886 887 /* resume dev_replace procedure that was interrupted by unmount */ 888 int btrfs_resume_dev_replace_async(struct btrfs_fs_info *fs_info) 889 { 890 struct task_struct *task; 891 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace; 892 893 btrfs_dev_replace_write_lock(dev_replace); 894 switch (dev_replace->replace_state) { 895 case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED: 896 case BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED: 897 case BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED: 898 btrfs_dev_replace_write_unlock(dev_replace); 899 return 0; 900 case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED: 901 break; 902 case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED: 903 dev_replace->replace_state = 904 BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED; 905 break; 906 } 907 if (!dev_replace->tgtdev || !dev_replace->tgtdev->bdev) { 908 btrfs_info(fs_info, 909 "cannot continue dev_replace, tgtdev is missing"); 910 btrfs_info(fs_info, 911 "you may cancel the operation after 'mount -o degraded'"); 912 dev_replace->replace_state = 913 BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED; 914 btrfs_dev_replace_write_unlock(dev_replace); 915 return 0; 916 } 917 btrfs_dev_replace_write_unlock(dev_replace); 918 919 /* 920 * This could collide with a paused balance, but the exclusive op logic 921 * should never allow both to start and pause. We don't want to allow 922 * dev-replace to start anyway. 923 */ 924 if (test_and_set_bit(BTRFS_FS_EXCL_OP, &fs_info->flags)) { 925 btrfs_dev_replace_write_lock(dev_replace); 926 dev_replace->replace_state = 927 BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED; 928 btrfs_dev_replace_write_unlock(dev_replace); 929 btrfs_info(fs_info, 930 "cannot resume dev-replace, other exclusive operation running"); 931 return 0; 932 } 933 934 task = kthread_run(btrfs_dev_replace_kthread, fs_info, "btrfs-devrepl"); 935 return PTR_ERR_OR_ZERO(task); 936 } 937 938 static int btrfs_dev_replace_kthread(void *data) 939 { 940 struct btrfs_fs_info *fs_info = data; 941 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace; 942 u64 progress; 943 int ret; 944 945 progress = btrfs_dev_replace_progress(fs_info); 946 progress = div_u64(progress, 10); 947 btrfs_info_in_rcu(fs_info, 948 "continuing dev_replace from %s (devid %llu) to target %s @%u%%", 949 btrfs_dev_name(dev_replace->srcdev), 950 dev_replace->srcdev->devid, 951 btrfs_dev_name(dev_replace->tgtdev), 952 (unsigned int)progress); 953 954 ret = btrfs_scrub_dev(fs_info, dev_replace->srcdev->devid, 955 dev_replace->committed_cursor_left, 956 btrfs_device_get_total_bytes(dev_replace->srcdev), 957 &dev_replace->scrub_progress, 0, 1); 958 ret = btrfs_dev_replace_finishing(fs_info, ret); 959 WARN_ON(ret); 960 961 clear_bit(BTRFS_FS_EXCL_OP, &fs_info->flags); 962 return 0; 963 } 964 965 int btrfs_dev_replace_is_ongoing(struct btrfs_dev_replace *dev_replace) 966 { 967 if (!dev_replace->is_valid) 968 return 0; 969 970 switch (dev_replace->replace_state) { 971 case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED: 972 case BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED: 973 case BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED: 974 return 0; 975 case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED: 976 case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED: 977 /* 978 * return true even if tgtdev is missing (this is 979 * something that can happen if the dev_replace 980 * procedure is suspended by an umount and then 981 * the tgtdev is missing (or "btrfs dev scan") was 982 * not called and the the filesystem is remounted 983 * in degraded state. This does not stop the 984 * dev_replace procedure. It needs to be canceled 985 * manually if the cancellation is wanted. 986 */ 987 break; 988 } 989 return 1; 990 } 991 992 void btrfs_dev_replace_read_lock(struct btrfs_dev_replace *dev_replace) 993 { 994 read_lock(&dev_replace->lock); 995 } 996 997 void btrfs_dev_replace_read_unlock(struct btrfs_dev_replace *dev_replace) 998 { 999 read_unlock(&dev_replace->lock); 1000 } 1001 1002 void btrfs_dev_replace_write_lock(struct btrfs_dev_replace *dev_replace) 1003 { 1004 again: 1005 wait_event(dev_replace->read_lock_wq, 1006 atomic_read(&dev_replace->blocking_readers) == 0); 1007 write_lock(&dev_replace->lock); 1008 if (atomic_read(&dev_replace->blocking_readers)) { 1009 write_unlock(&dev_replace->lock); 1010 goto again; 1011 } 1012 } 1013 1014 void btrfs_dev_replace_write_unlock(struct btrfs_dev_replace *dev_replace) 1015 { 1016 write_unlock(&dev_replace->lock); 1017 } 1018 1019 /* inc blocking cnt and release read lock */ 1020 void btrfs_dev_replace_set_lock_blocking( 1021 struct btrfs_dev_replace *dev_replace) 1022 { 1023 /* only set blocking for read lock */ 1024 atomic_inc(&dev_replace->blocking_readers); 1025 read_unlock(&dev_replace->lock); 1026 } 1027 1028 void btrfs_bio_counter_inc_noblocked(struct btrfs_fs_info *fs_info) 1029 { 1030 percpu_counter_inc(&fs_info->dev_replace.bio_counter); 1031 } 1032 1033 void btrfs_bio_counter_sub(struct btrfs_fs_info *fs_info, s64 amount) 1034 { 1035 percpu_counter_sub(&fs_info->dev_replace.bio_counter, amount); 1036 cond_wake_up_nomb(&fs_info->dev_replace.replace_wait); 1037 } 1038 1039 void btrfs_bio_counter_inc_blocked(struct btrfs_fs_info *fs_info) 1040 { 1041 while (1) { 1042 percpu_counter_inc(&fs_info->dev_replace.bio_counter); 1043 if (likely(!test_bit(BTRFS_FS_STATE_DEV_REPLACING, 1044 &fs_info->fs_state))) 1045 break; 1046 1047 btrfs_bio_counter_dec(fs_info); 1048 wait_event(fs_info->dev_replace.replace_wait, 1049 !test_bit(BTRFS_FS_STATE_DEV_REPLACING, 1050 &fs_info->fs_state)); 1051 } 1052 } 1053