1 /* 2 * Copyright (C) STRATO AG 2012. All rights reserved. 3 * 4 * This program is free software; you can redistribute it and/or 5 * modify it under the terms of the GNU General Public 6 * License v2 as published by the Free Software Foundation. 7 * 8 * This program is distributed in the hope that it will be useful, 9 * but WITHOUT ANY WARRANTY; without even the implied warranty of 10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 11 * General Public License for more details. 12 * 13 * You should have received a copy of the GNU General Public 14 * License along with this program; if not, write to the 15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330, 16 * Boston, MA 021110-1307, USA. 17 */ 18 #include <linux/sched.h> 19 #include <linux/bio.h> 20 #include <linux/slab.h> 21 #include <linux/buffer_head.h> 22 #include <linux/blkdev.h> 23 #include <linux/random.h> 24 #include <linux/iocontext.h> 25 #include <linux/capability.h> 26 #include <linux/kthread.h> 27 #include <linux/math64.h> 28 #include <asm/div64.h> 29 #include "ctree.h" 30 #include "extent_map.h" 31 #include "disk-io.h" 32 #include "transaction.h" 33 #include "print-tree.h" 34 #include "volumes.h" 35 #include "async-thread.h" 36 #include "check-integrity.h" 37 #include "rcu-string.h" 38 #include "dev-replace.h" 39 #include "sysfs.h" 40 41 static int btrfs_dev_replace_finishing(struct btrfs_fs_info *fs_info, 42 int scrub_ret); 43 static void btrfs_dev_replace_update_device_in_mapping_tree( 44 struct btrfs_fs_info *fs_info, 45 struct btrfs_device *srcdev, 46 struct btrfs_device *tgtdev); 47 static int btrfs_dev_replace_kthread(void *data); 48 static int btrfs_dev_replace_continue_on_mount(struct btrfs_fs_info *fs_info); 49 50 51 int btrfs_init_dev_replace(struct btrfs_fs_info *fs_info) 52 { 53 struct btrfs_key key; 54 struct btrfs_root *dev_root = fs_info->dev_root; 55 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace; 56 struct extent_buffer *eb; 57 int slot; 58 int ret = 0; 59 struct btrfs_path *path = NULL; 60 int item_size; 61 struct btrfs_dev_replace_item *ptr; 62 u64 src_devid; 63 64 path = btrfs_alloc_path(); 65 if (!path) { 66 ret = -ENOMEM; 67 goto out; 68 } 69 70 key.objectid = 0; 71 key.type = BTRFS_DEV_REPLACE_KEY; 72 key.offset = 0; 73 ret = btrfs_search_slot(NULL, dev_root, &key, path, 0, 0); 74 if (ret) { 75 no_valid_dev_replace_entry_found: 76 ret = 0; 77 dev_replace->replace_state = 78 BTRFS_DEV_REPLACE_ITEM_STATE_NEVER_STARTED; 79 dev_replace->cont_reading_from_srcdev_mode = 80 BTRFS_DEV_REPLACE_ITEM_CONT_READING_FROM_SRCDEV_MODE_ALWAYS; 81 dev_replace->replace_state = 0; 82 dev_replace->time_started = 0; 83 dev_replace->time_stopped = 0; 84 atomic64_set(&dev_replace->num_write_errors, 0); 85 atomic64_set(&dev_replace->num_uncorrectable_read_errors, 0); 86 dev_replace->cursor_left = 0; 87 dev_replace->committed_cursor_left = 0; 88 dev_replace->cursor_left_last_write_of_item = 0; 89 dev_replace->cursor_right = 0; 90 dev_replace->srcdev = NULL; 91 dev_replace->tgtdev = NULL; 92 dev_replace->is_valid = 0; 93 dev_replace->item_needs_writeback = 0; 94 goto out; 95 } 96 slot = path->slots[0]; 97 eb = path->nodes[0]; 98 item_size = btrfs_item_size_nr(eb, slot); 99 ptr = btrfs_item_ptr(eb, slot, struct btrfs_dev_replace_item); 100 101 if (item_size != sizeof(struct btrfs_dev_replace_item)) { 102 btrfs_warn(fs_info, 103 "dev_replace entry found has unexpected size, ignore entry"); 104 goto no_valid_dev_replace_entry_found; 105 } 106 107 src_devid = btrfs_dev_replace_src_devid(eb, ptr); 108 dev_replace->cont_reading_from_srcdev_mode = 109 btrfs_dev_replace_cont_reading_from_srcdev_mode(eb, ptr); 110 dev_replace->replace_state = btrfs_dev_replace_replace_state(eb, ptr); 111 dev_replace->time_started = btrfs_dev_replace_time_started(eb, ptr); 112 dev_replace->time_stopped = 113 btrfs_dev_replace_time_stopped(eb, ptr); 114 atomic64_set(&dev_replace->num_write_errors, 115 btrfs_dev_replace_num_write_errors(eb, ptr)); 116 atomic64_set(&dev_replace->num_uncorrectable_read_errors, 117 btrfs_dev_replace_num_uncorrectable_read_errors(eb, ptr)); 118 dev_replace->cursor_left = btrfs_dev_replace_cursor_left(eb, ptr); 119 dev_replace->committed_cursor_left = dev_replace->cursor_left; 120 dev_replace->cursor_left_last_write_of_item = dev_replace->cursor_left; 121 dev_replace->cursor_right = btrfs_dev_replace_cursor_right(eb, ptr); 122 dev_replace->is_valid = 1; 123 124 dev_replace->item_needs_writeback = 0; 125 switch (dev_replace->replace_state) { 126 case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED: 127 case BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED: 128 case BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED: 129 dev_replace->srcdev = NULL; 130 dev_replace->tgtdev = NULL; 131 break; 132 case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED: 133 case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED: 134 dev_replace->srcdev = btrfs_find_device(fs_info, src_devid, 135 NULL, NULL); 136 dev_replace->tgtdev = btrfs_find_device(fs_info, 137 BTRFS_DEV_REPLACE_DEVID, 138 NULL, NULL); 139 /* 140 * allow 'btrfs dev replace_cancel' if src/tgt device is 141 * missing 142 */ 143 if (!dev_replace->srcdev && 144 !btrfs_test_opt(fs_info, DEGRADED)) { 145 ret = -EIO; 146 btrfs_warn(fs_info, 147 "cannot mount because device replace operation is ongoing and"); 148 btrfs_warn(fs_info, 149 "srcdev (devid %llu) is missing, need to run 'btrfs dev scan'?", 150 src_devid); 151 } 152 if (!dev_replace->tgtdev && 153 !btrfs_test_opt(fs_info, DEGRADED)) { 154 ret = -EIO; 155 btrfs_warn(fs_info, 156 "cannot mount because device replace operation is ongoing and"); 157 btrfs_warn(fs_info, 158 "tgtdev (devid %llu) is missing, need to run 'btrfs dev scan'?", 159 BTRFS_DEV_REPLACE_DEVID); 160 } 161 if (dev_replace->tgtdev) { 162 if (dev_replace->srcdev) { 163 dev_replace->tgtdev->total_bytes = 164 dev_replace->srcdev->total_bytes; 165 dev_replace->tgtdev->disk_total_bytes = 166 dev_replace->srcdev->disk_total_bytes; 167 dev_replace->tgtdev->commit_total_bytes = 168 dev_replace->srcdev->commit_total_bytes; 169 dev_replace->tgtdev->bytes_used = 170 dev_replace->srcdev->bytes_used; 171 dev_replace->tgtdev->commit_bytes_used = 172 dev_replace->srcdev->commit_bytes_used; 173 } 174 set_bit(BTRFS_DEV_STATE_REPLACE_TGT, 175 &dev_replace->tgtdev->dev_state); 176 btrfs_init_dev_replace_tgtdev_for_resume(fs_info, 177 dev_replace->tgtdev); 178 } 179 break; 180 } 181 182 out: 183 btrfs_free_path(path); 184 return ret; 185 } 186 187 /* 188 * called from commit_transaction. Writes changed device replace state to 189 * disk. 190 */ 191 int btrfs_run_dev_replace(struct btrfs_trans_handle *trans, 192 struct btrfs_fs_info *fs_info) 193 { 194 int ret; 195 struct btrfs_root *dev_root = fs_info->dev_root; 196 struct btrfs_path *path; 197 struct btrfs_key key; 198 struct extent_buffer *eb; 199 struct btrfs_dev_replace_item *ptr; 200 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace; 201 202 btrfs_dev_replace_lock(dev_replace, 0); 203 if (!dev_replace->is_valid || 204 !dev_replace->item_needs_writeback) { 205 btrfs_dev_replace_unlock(dev_replace, 0); 206 return 0; 207 } 208 btrfs_dev_replace_unlock(dev_replace, 0); 209 210 key.objectid = 0; 211 key.type = BTRFS_DEV_REPLACE_KEY; 212 key.offset = 0; 213 214 path = btrfs_alloc_path(); 215 if (!path) { 216 ret = -ENOMEM; 217 goto out; 218 } 219 ret = btrfs_search_slot(trans, dev_root, &key, path, -1, 1); 220 if (ret < 0) { 221 btrfs_warn(fs_info, 222 "error %d while searching for dev_replace item!", 223 ret); 224 goto out; 225 } 226 227 if (ret == 0 && 228 btrfs_item_size_nr(path->nodes[0], path->slots[0]) < sizeof(*ptr)) { 229 /* 230 * need to delete old one and insert a new one. 231 * Since no attempt is made to recover any old state, if the 232 * dev_replace state is 'running', the data on the target 233 * drive is lost. 234 * It would be possible to recover the state: just make sure 235 * that the beginning of the item is never changed and always 236 * contains all the essential information. Then read this 237 * minimal set of information and use it as a base for the 238 * new state. 239 */ 240 ret = btrfs_del_item(trans, dev_root, path); 241 if (ret != 0) { 242 btrfs_warn(fs_info, 243 "delete too small dev_replace item failed %d!", 244 ret); 245 goto out; 246 } 247 ret = 1; 248 } 249 250 if (ret == 1) { 251 /* need to insert a new item */ 252 btrfs_release_path(path); 253 ret = btrfs_insert_empty_item(trans, dev_root, path, 254 &key, sizeof(*ptr)); 255 if (ret < 0) { 256 btrfs_warn(fs_info, 257 "insert dev_replace item failed %d!", ret); 258 goto out; 259 } 260 } 261 262 eb = path->nodes[0]; 263 ptr = btrfs_item_ptr(eb, path->slots[0], 264 struct btrfs_dev_replace_item); 265 266 btrfs_dev_replace_lock(dev_replace, 1); 267 if (dev_replace->srcdev) 268 btrfs_set_dev_replace_src_devid(eb, ptr, 269 dev_replace->srcdev->devid); 270 else 271 btrfs_set_dev_replace_src_devid(eb, ptr, (u64)-1); 272 btrfs_set_dev_replace_cont_reading_from_srcdev_mode(eb, ptr, 273 dev_replace->cont_reading_from_srcdev_mode); 274 btrfs_set_dev_replace_replace_state(eb, ptr, 275 dev_replace->replace_state); 276 btrfs_set_dev_replace_time_started(eb, ptr, dev_replace->time_started); 277 btrfs_set_dev_replace_time_stopped(eb, ptr, dev_replace->time_stopped); 278 btrfs_set_dev_replace_num_write_errors(eb, ptr, 279 atomic64_read(&dev_replace->num_write_errors)); 280 btrfs_set_dev_replace_num_uncorrectable_read_errors(eb, ptr, 281 atomic64_read(&dev_replace->num_uncorrectable_read_errors)); 282 dev_replace->cursor_left_last_write_of_item = 283 dev_replace->cursor_left; 284 btrfs_set_dev_replace_cursor_left(eb, ptr, 285 dev_replace->cursor_left_last_write_of_item); 286 btrfs_set_dev_replace_cursor_right(eb, ptr, 287 dev_replace->cursor_right); 288 dev_replace->item_needs_writeback = 0; 289 btrfs_dev_replace_unlock(dev_replace, 1); 290 291 btrfs_mark_buffer_dirty(eb); 292 293 out: 294 btrfs_free_path(path); 295 296 return ret; 297 } 298 299 void btrfs_after_dev_replace_commit(struct btrfs_fs_info *fs_info) 300 { 301 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace; 302 303 dev_replace->committed_cursor_left = 304 dev_replace->cursor_left_last_write_of_item; 305 } 306 307 static char* btrfs_dev_name(struct btrfs_device *device) 308 { 309 if (test_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state)) 310 return "<missing disk>"; 311 else 312 return rcu_str_deref(device->name); 313 } 314 315 int btrfs_dev_replace_start(struct btrfs_fs_info *fs_info, 316 const char *tgtdev_name, u64 srcdevid, const char *srcdev_name, 317 int read_src) 318 { 319 struct btrfs_root *root = fs_info->dev_root; 320 struct btrfs_trans_handle *trans; 321 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace; 322 int ret; 323 struct btrfs_device *tgt_device = NULL; 324 struct btrfs_device *src_device = NULL; 325 326 /* the disk copy procedure reuses the scrub code */ 327 mutex_lock(&fs_info->volume_mutex); 328 ret = btrfs_find_device_by_devspec(fs_info, srcdevid, 329 srcdev_name, &src_device); 330 if (ret) { 331 mutex_unlock(&fs_info->volume_mutex); 332 return ret; 333 } 334 335 ret = btrfs_init_dev_replace_tgtdev(fs_info, tgtdev_name, 336 src_device, &tgt_device); 337 mutex_unlock(&fs_info->volume_mutex); 338 if (ret) 339 return ret; 340 341 /* 342 * Here we commit the transaction to make sure commit_total_bytes 343 * of all the devices are updated. 344 */ 345 trans = btrfs_attach_transaction(root); 346 if (!IS_ERR(trans)) { 347 ret = btrfs_commit_transaction(trans); 348 if (ret) 349 return ret; 350 } else if (PTR_ERR(trans) != -ENOENT) { 351 return PTR_ERR(trans); 352 } 353 354 btrfs_dev_replace_lock(dev_replace, 1); 355 switch (dev_replace->replace_state) { 356 case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED: 357 case BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED: 358 case BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED: 359 break; 360 case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED: 361 case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED: 362 ret = BTRFS_IOCTL_DEV_REPLACE_RESULT_ALREADY_STARTED; 363 goto leave; 364 } 365 366 dev_replace->cont_reading_from_srcdev_mode = read_src; 367 WARN_ON(!src_device); 368 dev_replace->srcdev = src_device; 369 WARN_ON(!tgt_device); 370 dev_replace->tgtdev = tgt_device; 371 372 btrfs_info_in_rcu(fs_info, 373 "dev_replace from %s (devid %llu) to %s started", 374 btrfs_dev_name(src_device), 375 src_device->devid, 376 rcu_str_deref(tgt_device->name)); 377 378 /* 379 * from now on, the writes to the srcdev are all duplicated to 380 * go to the tgtdev as well (refer to btrfs_map_block()). 381 */ 382 dev_replace->replace_state = BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED; 383 dev_replace->time_started = get_seconds(); 384 dev_replace->cursor_left = 0; 385 dev_replace->committed_cursor_left = 0; 386 dev_replace->cursor_left_last_write_of_item = 0; 387 dev_replace->cursor_right = 0; 388 dev_replace->is_valid = 1; 389 dev_replace->item_needs_writeback = 1; 390 atomic64_set(&dev_replace->num_write_errors, 0); 391 atomic64_set(&dev_replace->num_uncorrectable_read_errors, 0); 392 btrfs_dev_replace_unlock(dev_replace, 1); 393 394 ret = btrfs_sysfs_add_device_link(tgt_device->fs_devices, tgt_device); 395 if (ret) 396 btrfs_err(fs_info, "kobj add dev failed %d", ret); 397 398 btrfs_wait_ordered_roots(fs_info, U64_MAX, 0, (u64)-1); 399 400 /* force writing the updated state information to disk */ 401 trans = btrfs_start_transaction(root, 0); 402 if (IS_ERR(trans)) { 403 ret = PTR_ERR(trans); 404 btrfs_dev_replace_lock(dev_replace, 1); 405 goto leave; 406 } 407 408 ret = btrfs_commit_transaction(trans); 409 WARN_ON(ret); 410 411 /* the disk copy procedure reuses the scrub code */ 412 ret = btrfs_scrub_dev(fs_info, src_device->devid, 0, 413 btrfs_device_get_total_bytes(src_device), 414 &dev_replace->scrub_progress, 0, 1); 415 416 ret = btrfs_dev_replace_finishing(fs_info, ret); 417 if (ret == -EINPROGRESS) { 418 ret = BTRFS_IOCTL_DEV_REPLACE_RESULT_SCRUB_INPROGRESS; 419 } else { 420 WARN_ON(ret); 421 } 422 423 return ret; 424 425 leave: 426 dev_replace->srcdev = NULL; 427 dev_replace->tgtdev = NULL; 428 btrfs_dev_replace_unlock(dev_replace, 1); 429 btrfs_destroy_dev_replace_tgtdev(fs_info, tgt_device); 430 return ret; 431 } 432 433 int btrfs_dev_replace_by_ioctl(struct btrfs_fs_info *fs_info, 434 struct btrfs_ioctl_dev_replace_args *args) 435 { 436 int ret; 437 438 switch (args->start.cont_reading_from_srcdev_mode) { 439 case BTRFS_IOCTL_DEV_REPLACE_CONT_READING_FROM_SRCDEV_MODE_ALWAYS: 440 case BTRFS_IOCTL_DEV_REPLACE_CONT_READING_FROM_SRCDEV_MODE_AVOID: 441 break; 442 default: 443 return -EINVAL; 444 } 445 446 if ((args->start.srcdevid == 0 && args->start.srcdev_name[0] == '\0') || 447 args->start.tgtdev_name[0] == '\0') 448 return -EINVAL; 449 450 ret = btrfs_dev_replace_start(fs_info, args->start.tgtdev_name, 451 args->start.srcdevid, 452 args->start.srcdev_name, 453 args->start.cont_reading_from_srcdev_mode); 454 args->result = ret; 455 /* don't warn if EINPROGRESS, someone else might be running scrub */ 456 if (ret == BTRFS_IOCTL_DEV_REPLACE_RESULT_SCRUB_INPROGRESS) 457 ret = 0; 458 459 return ret; 460 } 461 462 /* 463 * blocked until all in-flight bios operations are finished. 464 */ 465 static void btrfs_rm_dev_replace_blocked(struct btrfs_fs_info *fs_info) 466 { 467 set_bit(BTRFS_FS_STATE_DEV_REPLACING, &fs_info->fs_state); 468 wait_event(fs_info->replace_wait, !percpu_counter_sum( 469 &fs_info->bio_counter)); 470 } 471 472 /* 473 * we have removed target device, it is safe to allow new bios request. 474 */ 475 static void btrfs_rm_dev_replace_unblocked(struct btrfs_fs_info *fs_info) 476 { 477 clear_bit(BTRFS_FS_STATE_DEV_REPLACING, &fs_info->fs_state); 478 wake_up(&fs_info->replace_wait); 479 } 480 481 static int btrfs_dev_replace_finishing(struct btrfs_fs_info *fs_info, 482 int scrub_ret) 483 { 484 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace; 485 struct btrfs_device *tgt_device; 486 struct btrfs_device *src_device; 487 struct btrfs_root *root = fs_info->tree_root; 488 u8 uuid_tmp[BTRFS_UUID_SIZE]; 489 struct btrfs_trans_handle *trans; 490 int ret = 0; 491 492 /* don't allow cancel or unmount to disturb the finishing procedure */ 493 mutex_lock(&dev_replace->lock_finishing_cancel_unmount); 494 495 btrfs_dev_replace_lock(dev_replace, 0); 496 /* was the operation canceled, or is it finished? */ 497 if (dev_replace->replace_state != 498 BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED) { 499 btrfs_dev_replace_unlock(dev_replace, 0); 500 mutex_unlock(&dev_replace->lock_finishing_cancel_unmount); 501 return 0; 502 } 503 504 tgt_device = dev_replace->tgtdev; 505 src_device = dev_replace->srcdev; 506 btrfs_dev_replace_unlock(dev_replace, 0); 507 508 /* 509 * flush all outstanding I/O and inode extent mappings before the 510 * copy operation is declared as being finished 511 */ 512 ret = btrfs_start_delalloc_roots(fs_info, 0, -1); 513 if (ret) { 514 mutex_unlock(&dev_replace->lock_finishing_cancel_unmount); 515 return ret; 516 } 517 btrfs_wait_ordered_roots(fs_info, U64_MAX, 0, (u64)-1); 518 519 trans = btrfs_start_transaction(root, 0); 520 if (IS_ERR(trans)) { 521 mutex_unlock(&dev_replace->lock_finishing_cancel_unmount); 522 return PTR_ERR(trans); 523 } 524 ret = btrfs_commit_transaction(trans); 525 WARN_ON(ret); 526 527 mutex_lock(&uuid_mutex); 528 /* keep away write_all_supers() during the finishing procedure */ 529 mutex_lock(&fs_info->fs_devices->device_list_mutex); 530 mutex_lock(&fs_info->chunk_mutex); 531 btrfs_dev_replace_lock(dev_replace, 1); 532 dev_replace->replace_state = 533 scrub_ret ? BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED 534 : BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED; 535 dev_replace->tgtdev = NULL; 536 dev_replace->srcdev = NULL; 537 dev_replace->time_stopped = get_seconds(); 538 dev_replace->item_needs_writeback = 1; 539 540 /* replace old device with new one in mapping tree */ 541 if (!scrub_ret) { 542 btrfs_dev_replace_update_device_in_mapping_tree(fs_info, 543 src_device, 544 tgt_device); 545 } else { 546 btrfs_err_in_rcu(fs_info, 547 "btrfs_scrub_dev(%s, %llu, %s) failed %d", 548 btrfs_dev_name(src_device), 549 src_device->devid, 550 rcu_str_deref(tgt_device->name), scrub_ret); 551 btrfs_dev_replace_unlock(dev_replace, 1); 552 mutex_unlock(&fs_info->chunk_mutex); 553 mutex_unlock(&fs_info->fs_devices->device_list_mutex); 554 mutex_unlock(&uuid_mutex); 555 btrfs_rm_dev_replace_blocked(fs_info); 556 if (tgt_device) 557 btrfs_destroy_dev_replace_tgtdev(fs_info, tgt_device); 558 btrfs_rm_dev_replace_unblocked(fs_info); 559 mutex_unlock(&dev_replace->lock_finishing_cancel_unmount); 560 561 return scrub_ret; 562 } 563 564 btrfs_info_in_rcu(fs_info, 565 "dev_replace from %s (devid %llu) to %s finished", 566 btrfs_dev_name(src_device), 567 src_device->devid, 568 rcu_str_deref(tgt_device->name)); 569 clear_bit(BTRFS_DEV_STATE_REPLACE_TGT, &tgt_device->dev_state); 570 tgt_device->devid = src_device->devid; 571 src_device->devid = BTRFS_DEV_REPLACE_DEVID; 572 memcpy(uuid_tmp, tgt_device->uuid, sizeof(uuid_tmp)); 573 memcpy(tgt_device->uuid, src_device->uuid, sizeof(tgt_device->uuid)); 574 memcpy(src_device->uuid, uuid_tmp, sizeof(src_device->uuid)); 575 btrfs_device_set_total_bytes(tgt_device, src_device->total_bytes); 576 btrfs_device_set_disk_total_bytes(tgt_device, 577 src_device->disk_total_bytes); 578 btrfs_device_set_bytes_used(tgt_device, src_device->bytes_used); 579 ASSERT(list_empty(&src_device->resized_list)); 580 tgt_device->commit_total_bytes = src_device->commit_total_bytes; 581 tgt_device->commit_bytes_used = src_device->bytes_used; 582 583 btrfs_assign_next_active_device(fs_info, src_device, tgt_device); 584 585 list_add(&tgt_device->dev_alloc_list, &fs_info->fs_devices->alloc_list); 586 fs_info->fs_devices->rw_devices++; 587 588 btrfs_dev_replace_unlock(dev_replace, 1); 589 590 btrfs_rm_dev_replace_blocked(fs_info); 591 592 btrfs_rm_dev_replace_remove_srcdev(fs_info, src_device); 593 594 btrfs_rm_dev_replace_unblocked(fs_info); 595 596 /* 597 * this is again a consistent state where no dev_replace procedure 598 * is running, the target device is part of the filesystem, the 599 * source device is not part of the filesystem anymore and its 1st 600 * superblock is scratched out so that it is no longer marked to 601 * belong to this filesystem. 602 */ 603 mutex_unlock(&fs_info->chunk_mutex); 604 mutex_unlock(&fs_info->fs_devices->device_list_mutex); 605 mutex_unlock(&uuid_mutex); 606 607 /* replace the sysfs entry */ 608 btrfs_sysfs_rm_device_link(fs_info->fs_devices, src_device); 609 btrfs_rm_dev_replace_free_srcdev(fs_info, src_device); 610 611 /* write back the superblocks */ 612 trans = btrfs_start_transaction(root, 0); 613 if (!IS_ERR(trans)) 614 btrfs_commit_transaction(trans); 615 616 mutex_unlock(&dev_replace->lock_finishing_cancel_unmount); 617 618 return 0; 619 } 620 621 static void btrfs_dev_replace_update_device_in_mapping_tree( 622 struct btrfs_fs_info *fs_info, 623 struct btrfs_device *srcdev, 624 struct btrfs_device *tgtdev) 625 { 626 struct extent_map_tree *em_tree = &fs_info->mapping_tree.map_tree; 627 struct extent_map *em; 628 struct map_lookup *map; 629 u64 start = 0; 630 int i; 631 632 write_lock(&em_tree->lock); 633 do { 634 em = lookup_extent_mapping(em_tree, start, (u64)-1); 635 if (!em) 636 break; 637 map = em->map_lookup; 638 for (i = 0; i < map->num_stripes; i++) 639 if (srcdev == map->stripes[i].dev) 640 map->stripes[i].dev = tgtdev; 641 start = em->start + em->len; 642 free_extent_map(em); 643 } while (start); 644 write_unlock(&em_tree->lock); 645 } 646 647 /* 648 * Read progress of device replace status according to the state and last 649 * stored position. The value format is the same as for 650 * btrfs_dev_replace::progress_1000 651 */ 652 static u64 btrfs_dev_replace_progress(struct btrfs_fs_info *fs_info) 653 { 654 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace; 655 u64 ret = 0; 656 657 switch (dev_replace->replace_state) { 658 case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED: 659 case BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED: 660 ret = 0; 661 break; 662 case BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED: 663 ret = 1000; 664 break; 665 case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED: 666 case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED: 667 ret = div64_u64(dev_replace->cursor_left, 668 div_u64(btrfs_device_get_total_bytes( 669 dev_replace->srcdev), 1000)); 670 break; 671 } 672 673 return ret; 674 } 675 676 void btrfs_dev_replace_status(struct btrfs_fs_info *fs_info, 677 struct btrfs_ioctl_dev_replace_args *args) 678 { 679 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace; 680 681 btrfs_dev_replace_lock(dev_replace, 0); 682 /* even if !dev_replace_is_valid, the values are good enough for 683 * the replace_status ioctl */ 684 args->result = BTRFS_IOCTL_DEV_REPLACE_RESULT_NO_ERROR; 685 args->status.replace_state = dev_replace->replace_state; 686 args->status.time_started = dev_replace->time_started; 687 args->status.time_stopped = dev_replace->time_stopped; 688 args->status.num_write_errors = 689 atomic64_read(&dev_replace->num_write_errors); 690 args->status.num_uncorrectable_read_errors = 691 atomic64_read(&dev_replace->num_uncorrectable_read_errors); 692 args->status.progress_1000 = btrfs_dev_replace_progress(fs_info); 693 btrfs_dev_replace_unlock(dev_replace, 0); 694 } 695 696 u64 __btrfs_dev_replace_cancel(struct btrfs_fs_info *fs_info) 697 { 698 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace; 699 struct btrfs_device *tgt_device = NULL; 700 struct btrfs_trans_handle *trans; 701 struct btrfs_root *root = fs_info->tree_root; 702 u64 result; 703 int ret; 704 705 if (sb_rdonly(fs_info->sb)) 706 return -EROFS; 707 708 mutex_lock(&dev_replace->lock_finishing_cancel_unmount); 709 btrfs_dev_replace_lock(dev_replace, 1); 710 switch (dev_replace->replace_state) { 711 case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED: 712 case BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED: 713 case BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED: 714 result = BTRFS_IOCTL_DEV_REPLACE_RESULT_NOT_STARTED; 715 btrfs_dev_replace_unlock(dev_replace, 1); 716 goto leave; 717 case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED: 718 case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED: 719 result = BTRFS_IOCTL_DEV_REPLACE_RESULT_NO_ERROR; 720 tgt_device = dev_replace->tgtdev; 721 dev_replace->tgtdev = NULL; 722 dev_replace->srcdev = NULL; 723 break; 724 } 725 dev_replace->replace_state = BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED; 726 dev_replace->time_stopped = get_seconds(); 727 dev_replace->item_needs_writeback = 1; 728 btrfs_dev_replace_unlock(dev_replace, 1); 729 btrfs_scrub_cancel(fs_info); 730 731 trans = btrfs_start_transaction(root, 0); 732 if (IS_ERR(trans)) { 733 mutex_unlock(&dev_replace->lock_finishing_cancel_unmount); 734 return PTR_ERR(trans); 735 } 736 ret = btrfs_commit_transaction(trans); 737 WARN_ON(ret); 738 if (tgt_device) 739 btrfs_destroy_dev_replace_tgtdev(fs_info, tgt_device); 740 741 leave: 742 mutex_unlock(&dev_replace->lock_finishing_cancel_unmount); 743 return result; 744 } 745 746 void btrfs_dev_replace_suspend_for_unmount(struct btrfs_fs_info *fs_info) 747 { 748 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace; 749 750 mutex_lock(&dev_replace->lock_finishing_cancel_unmount); 751 btrfs_dev_replace_lock(dev_replace, 1); 752 switch (dev_replace->replace_state) { 753 case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED: 754 case BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED: 755 case BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED: 756 case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED: 757 break; 758 case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED: 759 dev_replace->replace_state = 760 BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED; 761 dev_replace->time_stopped = get_seconds(); 762 dev_replace->item_needs_writeback = 1; 763 btrfs_info(fs_info, "suspending dev_replace for unmount"); 764 break; 765 } 766 767 btrfs_dev_replace_unlock(dev_replace, 1); 768 mutex_unlock(&dev_replace->lock_finishing_cancel_unmount); 769 } 770 771 /* resume dev_replace procedure that was interrupted by unmount */ 772 int btrfs_resume_dev_replace_async(struct btrfs_fs_info *fs_info) 773 { 774 struct task_struct *task; 775 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace; 776 777 btrfs_dev_replace_lock(dev_replace, 1); 778 switch (dev_replace->replace_state) { 779 case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED: 780 case BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED: 781 case BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED: 782 btrfs_dev_replace_unlock(dev_replace, 1); 783 return 0; 784 case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED: 785 break; 786 case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED: 787 dev_replace->replace_state = 788 BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED; 789 break; 790 } 791 if (!dev_replace->tgtdev || !dev_replace->tgtdev->bdev) { 792 btrfs_info(fs_info, 793 "cannot continue dev_replace, tgtdev is missing"); 794 btrfs_info(fs_info, 795 "you may cancel the operation after 'mount -o degraded'"); 796 btrfs_dev_replace_unlock(dev_replace, 1); 797 return 0; 798 } 799 btrfs_dev_replace_unlock(dev_replace, 1); 800 801 WARN_ON(test_and_set_bit(BTRFS_FS_EXCL_OP, &fs_info->flags)); 802 task = kthread_run(btrfs_dev_replace_kthread, fs_info, "btrfs-devrepl"); 803 return PTR_ERR_OR_ZERO(task); 804 } 805 806 static int btrfs_dev_replace_kthread(void *data) 807 { 808 struct btrfs_fs_info *fs_info = data; 809 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace; 810 u64 progress; 811 812 progress = btrfs_dev_replace_progress(fs_info); 813 progress = div_u64(progress, 10); 814 btrfs_info_in_rcu(fs_info, 815 "continuing dev_replace from %s (devid %llu) to target %s @%u%%", 816 btrfs_dev_name(dev_replace->srcdev), 817 dev_replace->srcdev->devid, 818 btrfs_dev_name(dev_replace->tgtdev), 819 (unsigned int)progress); 820 821 btrfs_dev_replace_continue_on_mount(fs_info); 822 clear_bit(BTRFS_FS_EXCL_OP, &fs_info->flags); 823 824 return 0; 825 } 826 827 static int btrfs_dev_replace_continue_on_mount(struct btrfs_fs_info *fs_info) 828 { 829 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace; 830 int ret; 831 832 ret = btrfs_scrub_dev(fs_info, dev_replace->srcdev->devid, 833 dev_replace->committed_cursor_left, 834 btrfs_device_get_total_bytes(dev_replace->srcdev), 835 &dev_replace->scrub_progress, 0, 1); 836 ret = btrfs_dev_replace_finishing(fs_info, ret); 837 WARN_ON(ret); 838 return 0; 839 } 840 841 int btrfs_dev_replace_is_ongoing(struct btrfs_dev_replace *dev_replace) 842 { 843 if (!dev_replace->is_valid) 844 return 0; 845 846 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 return 0; 851 case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED: 852 case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED: 853 /* 854 * return true even if tgtdev is missing (this is 855 * something that can happen if the dev_replace 856 * procedure is suspended by an umount and then 857 * the tgtdev is missing (or "btrfs dev scan") was 858 * not called and the the filesystem is remounted 859 * in degraded state. This does not stop the 860 * dev_replace procedure. It needs to be canceled 861 * manually if the cancellation is wanted. 862 */ 863 break; 864 } 865 return 1; 866 } 867 868 void btrfs_dev_replace_lock(struct btrfs_dev_replace *dev_replace, int rw) 869 { 870 if (rw == 1) { 871 /* write */ 872 again: 873 wait_event(dev_replace->read_lock_wq, 874 atomic_read(&dev_replace->blocking_readers) == 0); 875 write_lock(&dev_replace->lock); 876 if (atomic_read(&dev_replace->blocking_readers)) { 877 write_unlock(&dev_replace->lock); 878 goto again; 879 } 880 } else { 881 read_lock(&dev_replace->lock); 882 atomic_inc(&dev_replace->read_locks); 883 } 884 } 885 886 void btrfs_dev_replace_unlock(struct btrfs_dev_replace *dev_replace, int rw) 887 { 888 if (rw == 1) { 889 /* write */ 890 ASSERT(atomic_read(&dev_replace->blocking_readers) == 0); 891 write_unlock(&dev_replace->lock); 892 } else { 893 ASSERT(atomic_read(&dev_replace->read_locks) > 0); 894 atomic_dec(&dev_replace->read_locks); 895 read_unlock(&dev_replace->lock); 896 } 897 } 898 899 /* inc blocking cnt and release read lock */ 900 void btrfs_dev_replace_set_lock_blocking( 901 struct btrfs_dev_replace *dev_replace) 902 { 903 /* only set blocking for read lock */ 904 ASSERT(atomic_read(&dev_replace->read_locks) > 0); 905 atomic_inc(&dev_replace->blocking_readers); 906 read_unlock(&dev_replace->lock); 907 } 908 909 /* acquire read lock and dec blocking cnt */ 910 void btrfs_dev_replace_clear_lock_blocking( 911 struct btrfs_dev_replace *dev_replace) 912 { 913 /* only set blocking for read lock */ 914 ASSERT(atomic_read(&dev_replace->read_locks) > 0); 915 ASSERT(atomic_read(&dev_replace->blocking_readers) > 0); 916 read_lock(&dev_replace->lock); 917 if (atomic_dec_and_test(&dev_replace->blocking_readers) && 918 waitqueue_active(&dev_replace->read_lock_wq)) 919 wake_up(&dev_replace->read_lock_wq); 920 } 921 922 void btrfs_bio_counter_inc_noblocked(struct btrfs_fs_info *fs_info) 923 { 924 percpu_counter_inc(&fs_info->bio_counter); 925 } 926 927 void btrfs_bio_counter_sub(struct btrfs_fs_info *fs_info, s64 amount) 928 { 929 percpu_counter_sub(&fs_info->bio_counter, amount); 930 931 if (waitqueue_active(&fs_info->replace_wait)) 932 wake_up(&fs_info->replace_wait); 933 } 934 935 void btrfs_bio_counter_inc_blocked(struct btrfs_fs_info *fs_info) 936 { 937 while (1) { 938 percpu_counter_inc(&fs_info->bio_counter); 939 if (likely(!test_bit(BTRFS_FS_STATE_DEV_REPLACING, 940 &fs_info->fs_state))) 941 break; 942 943 btrfs_bio_counter_dec(fs_info); 944 wait_event(fs_info->replace_wait, 945 !test_bit(BTRFS_FS_STATE_DEV_REPLACING, 946 &fs_info->fs_state)); 947 } 948 } 949