| 1 | /* |
| 2 | * Copyright (C) 2007 Oracle. 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/buffer_head.h> |
| 21 | #include <linux/blkdev.h> |
| 22 | #include <linux/random.h> |
| 23 | #include <asm/div64.h> |
| 24 | #include "compat.h" |
| 25 | #include "ctree.h" |
| 26 | #include "extent_map.h" |
| 27 | #include "disk-io.h" |
| 28 | #include "transaction.h" |
| 29 | #include "print-tree.h" |
| 30 | #include "volumes.h" |
| 31 | #include "async-thread.h" |
| 32 | |
| 33 | struct map_lookup { |
| 34 | u64 type; |
| 35 | int io_align; |
| 36 | int io_width; |
| 37 | int stripe_len; |
| 38 | int sector_size; |
| 39 | int num_stripes; |
| 40 | int sub_stripes; |
| 41 | struct btrfs_bio_stripe stripes[]; |
| 42 | }; |
| 43 | |
| 44 | static int init_first_rw_device(struct btrfs_trans_handle *trans, |
| 45 | struct btrfs_root *root, |
| 46 | struct btrfs_device *device); |
| 47 | static int btrfs_relocate_sys_chunks(struct btrfs_root *root); |
| 48 | |
| 49 | #define map_lookup_size(n) (sizeof(struct map_lookup) + \ |
| 50 | (sizeof(struct btrfs_bio_stripe) * (n))) |
| 51 | |
| 52 | static DEFINE_MUTEX(uuid_mutex); |
| 53 | static LIST_HEAD(fs_uuids); |
| 54 | |
| 55 | void btrfs_lock_volumes(void) |
| 56 | { |
| 57 | mutex_lock(&uuid_mutex); |
| 58 | } |
| 59 | |
| 60 | void btrfs_unlock_volumes(void) |
| 61 | { |
| 62 | mutex_unlock(&uuid_mutex); |
| 63 | } |
| 64 | |
| 65 | static void lock_chunks(struct btrfs_root *root) |
| 66 | { |
| 67 | mutex_lock(&root->fs_info->chunk_mutex); |
| 68 | } |
| 69 | |
| 70 | static void unlock_chunks(struct btrfs_root *root) |
| 71 | { |
| 72 | mutex_unlock(&root->fs_info->chunk_mutex); |
| 73 | } |
| 74 | |
| 75 | static void free_fs_devices(struct btrfs_fs_devices *fs_devices) |
| 76 | { |
| 77 | struct btrfs_device *device; |
| 78 | WARN_ON(fs_devices->opened); |
| 79 | while (!list_empty(&fs_devices->devices)) { |
| 80 | device = list_entry(fs_devices->devices.next, |
| 81 | struct btrfs_device, dev_list); |
| 82 | list_del(&device->dev_list); |
| 83 | kfree(device->name); |
| 84 | kfree(device); |
| 85 | } |
| 86 | kfree(fs_devices); |
| 87 | } |
| 88 | |
| 89 | int btrfs_cleanup_fs_uuids(void) |
| 90 | { |
| 91 | struct btrfs_fs_devices *fs_devices; |
| 92 | |
| 93 | while (!list_empty(&fs_uuids)) { |
| 94 | fs_devices = list_entry(fs_uuids.next, |
| 95 | struct btrfs_fs_devices, list); |
| 96 | list_del(&fs_devices->list); |
| 97 | free_fs_devices(fs_devices); |
| 98 | } |
| 99 | return 0; |
| 100 | } |
| 101 | |
| 102 | static noinline struct btrfs_device *__find_device(struct list_head *head, |
| 103 | u64 devid, u8 *uuid) |
| 104 | { |
| 105 | struct btrfs_device *dev; |
| 106 | |
| 107 | list_for_each_entry(dev, head, dev_list) { |
| 108 | if (dev->devid == devid && |
| 109 | (!uuid || !memcmp(dev->uuid, uuid, BTRFS_UUID_SIZE))) { |
| 110 | return dev; |
| 111 | } |
| 112 | } |
| 113 | return NULL; |
| 114 | } |
| 115 | |
| 116 | static noinline struct btrfs_fs_devices *find_fsid(u8 *fsid) |
| 117 | { |
| 118 | struct btrfs_fs_devices *fs_devices; |
| 119 | |
| 120 | list_for_each_entry(fs_devices, &fs_uuids, list) { |
| 121 | if (memcmp(fsid, fs_devices->fsid, BTRFS_FSID_SIZE) == 0) |
| 122 | return fs_devices; |
| 123 | } |
| 124 | return NULL; |
| 125 | } |
| 126 | |
| 127 | /* |
| 128 | * we try to collect pending bios for a device so we don't get a large |
| 129 | * number of procs sending bios down to the same device. This greatly |
| 130 | * improves the schedulers ability to collect and merge the bios. |
| 131 | * |
| 132 | * But, it also turns into a long list of bios to process and that is sure |
| 133 | * to eventually make the worker thread block. The solution here is to |
| 134 | * make some progress and then put this work struct back at the end of |
| 135 | * the list if the block device is congested. This way, multiple devices |
| 136 | * can make progress from a single worker thread. |
| 137 | */ |
| 138 | static noinline int run_scheduled_bios(struct btrfs_device *device) |
| 139 | { |
| 140 | struct bio *pending; |
| 141 | struct backing_dev_info *bdi; |
| 142 | struct btrfs_fs_info *fs_info; |
| 143 | struct bio *tail; |
| 144 | struct bio *cur; |
| 145 | int again = 0; |
| 146 | unsigned long num_run = 0; |
| 147 | unsigned long limit; |
| 148 | |
| 149 | bdi = device->bdev->bd_inode->i_mapping->backing_dev_info; |
| 150 | fs_info = device->dev_root->fs_info; |
| 151 | limit = btrfs_async_submit_limit(fs_info); |
| 152 | limit = limit * 2 / 3; |
| 153 | |
| 154 | loop: |
| 155 | spin_lock(&device->io_lock); |
| 156 | |
| 157 | /* take all the bios off the list at once and process them |
| 158 | * later on (without the lock held). But, remember the |
| 159 | * tail and other pointers so the bios can be properly reinserted |
| 160 | * into the list if we hit congestion |
| 161 | */ |
| 162 | pending = device->pending_bios; |
| 163 | tail = device->pending_bio_tail; |
| 164 | WARN_ON(pending && !tail); |
| 165 | device->pending_bios = NULL; |
| 166 | device->pending_bio_tail = NULL; |
| 167 | |
| 168 | /* |
| 169 | * if pending was null this time around, no bios need processing |
| 170 | * at all and we can stop. Otherwise it'll loop back up again |
| 171 | * and do an additional check so no bios are missed. |
| 172 | * |
| 173 | * device->running_pending is used to synchronize with the |
| 174 | * schedule_bio code. |
| 175 | */ |
| 176 | if (pending) { |
| 177 | again = 1; |
| 178 | device->running_pending = 1; |
| 179 | } else { |
| 180 | again = 0; |
| 181 | device->running_pending = 0; |
| 182 | } |
| 183 | spin_unlock(&device->io_lock); |
| 184 | |
| 185 | while (pending) { |
| 186 | cur = pending; |
| 187 | pending = pending->bi_next; |
| 188 | cur->bi_next = NULL; |
| 189 | atomic_dec(&fs_info->nr_async_bios); |
| 190 | |
| 191 | if (atomic_read(&fs_info->nr_async_bios) < limit && |
| 192 | waitqueue_active(&fs_info->async_submit_wait)) |
| 193 | wake_up(&fs_info->async_submit_wait); |
| 194 | |
| 195 | BUG_ON(atomic_read(&cur->bi_cnt) == 0); |
| 196 | bio_get(cur); |
| 197 | submit_bio(cur->bi_rw, cur); |
| 198 | bio_put(cur); |
| 199 | num_run++; |
| 200 | |
| 201 | /* |
| 202 | * we made progress, there is more work to do and the bdi |
| 203 | * is now congested. Back off and let other work structs |
| 204 | * run instead |
| 205 | */ |
| 206 | if (pending && bdi_write_congested(bdi) && |
| 207 | fs_info->fs_devices->open_devices > 1) { |
| 208 | struct bio *old_head; |
| 209 | |
| 210 | spin_lock(&device->io_lock); |
| 211 | |
| 212 | old_head = device->pending_bios; |
| 213 | device->pending_bios = pending; |
| 214 | if (device->pending_bio_tail) |
| 215 | tail->bi_next = old_head; |
| 216 | else |
| 217 | device->pending_bio_tail = tail; |
| 218 | device->running_pending = 0; |
| 219 | |
| 220 | spin_unlock(&device->io_lock); |
| 221 | btrfs_requeue_work(&device->work); |
| 222 | goto done; |
| 223 | } |
| 224 | } |
| 225 | if (again) |
| 226 | goto loop; |
| 227 | done: |
| 228 | return 0; |
| 229 | } |
| 230 | |
| 231 | static void pending_bios_fn(struct btrfs_work *work) |
| 232 | { |
| 233 | struct btrfs_device *device; |
| 234 | |
| 235 | device = container_of(work, struct btrfs_device, work); |
| 236 | run_scheduled_bios(device); |
| 237 | } |
| 238 | |
| 239 | static noinline int device_list_add(const char *path, |
| 240 | struct btrfs_super_block *disk_super, |
| 241 | u64 devid, struct btrfs_fs_devices **fs_devices_ret) |
| 242 | { |
| 243 | struct btrfs_device *device; |
| 244 | struct btrfs_fs_devices *fs_devices; |
| 245 | u64 found_transid = btrfs_super_generation(disk_super); |
| 246 | |
| 247 | fs_devices = find_fsid(disk_super->fsid); |
| 248 | if (!fs_devices) { |
| 249 | fs_devices = kzalloc(sizeof(*fs_devices), GFP_NOFS); |
| 250 | if (!fs_devices) |
| 251 | return -ENOMEM; |
| 252 | INIT_LIST_HEAD(&fs_devices->devices); |
| 253 | INIT_LIST_HEAD(&fs_devices->alloc_list); |
| 254 | list_add(&fs_devices->list, &fs_uuids); |
| 255 | memcpy(fs_devices->fsid, disk_super->fsid, BTRFS_FSID_SIZE); |
| 256 | fs_devices->latest_devid = devid; |
| 257 | fs_devices->latest_trans = found_transid; |
| 258 | device = NULL; |
| 259 | } else { |
| 260 | device = __find_device(&fs_devices->devices, devid, |
| 261 | disk_super->dev_item.uuid); |
| 262 | } |
| 263 | if (!device) { |
| 264 | if (fs_devices->opened) |
| 265 | return -EBUSY; |
| 266 | |
| 267 | device = kzalloc(sizeof(*device), GFP_NOFS); |
| 268 | if (!device) { |
| 269 | /* we can safely leave the fs_devices entry around */ |
| 270 | return -ENOMEM; |
| 271 | } |
| 272 | device->devid = devid; |
| 273 | device->work.func = pending_bios_fn; |
| 274 | memcpy(device->uuid, disk_super->dev_item.uuid, |
| 275 | BTRFS_UUID_SIZE); |
| 276 | device->barriers = 1; |
| 277 | spin_lock_init(&device->io_lock); |
| 278 | device->name = kstrdup(path, GFP_NOFS); |
| 279 | if (!device->name) { |
| 280 | kfree(device); |
| 281 | return -ENOMEM; |
| 282 | } |
| 283 | INIT_LIST_HEAD(&device->dev_alloc_list); |
| 284 | list_add(&device->dev_list, &fs_devices->devices); |
| 285 | device->fs_devices = fs_devices; |
| 286 | fs_devices->num_devices++; |
| 287 | } |
| 288 | |
| 289 | if (found_transid > fs_devices->latest_trans) { |
| 290 | fs_devices->latest_devid = devid; |
| 291 | fs_devices->latest_trans = found_transid; |
| 292 | } |
| 293 | *fs_devices_ret = fs_devices; |
| 294 | return 0; |
| 295 | } |
| 296 | |
| 297 | static struct btrfs_fs_devices *clone_fs_devices(struct btrfs_fs_devices *orig) |
| 298 | { |
| 299 | struct btrfs_fs_devices *fs_devices; |
| 300 | struct btrfs_device *device; |
| 301 | struct btrfs_device *orig_dev; |
| 302 | |
| 303 | fs_devices = kzalloc(sizeof(*fs_devices), GFP_NOFS); |
| 304 | if (!fs_devices) |
| 305 | return ERR_PTR(-ENOMEM); |
| 306 | |
| 307 | INIT_LIST_HEAD(&fs_devices->devices); |
| 308 | INIT_LIST_HEAD(&fs_devices->alloc_list); |
| 309 | INIT_LIST_HEAD(&fs_devices->list); |
| 310 | fs_devices->latest_devid = orig->latest_devid; |
| 311 | fs_devices->latest_trans = orig->latest_trans; |
| 312 | memcpy(fs_devices->fsid, orig->fsid, sizeof(fs_devices->fsid)); |
| 313 | |
| 314 | list_for_each_entry(orig_dev, &orig->devices, dev_list) { |
| 315 | device = kzalloc(sizeof(*device), GFP_NOFS); |
| 316 | if (!device) |
| 317 | goto error; |
| 318 | |
| 319 | device->name = kstrdup(orig_dev->name, GFP_NOFS); |
| 320 | if (!device->name) |
| 321 | goto error; |
| 322 | |
| 323 | device->devid = orig_dev->devid; |
| 324 | device->work.func = pending_bios_fn; |
| 325 | memcpy(device->uuid, orig_dev->uuid, sizeof(device->uuid)); |
| 326 | device->barriers = 1; |
| 327 | spin_lock_init(&device->io_lock); |
| 328 | INIT_LIST_HEAD(&device->dev_list); |
| 329 | INIT_LIST_HEAD(&device->dev_alloc_list); |
| 330 | |
| 331 | list_add(&device->dev_list, &fs_devices->devices); |
| 332 | device->fs_devices = fs_devices; |
| 333 | fs_devices->num_devices++; |
| 334 | } |
| 335 | return fs_devices; |
| 336 | error: |
| 337 | free_fs_devices(fs_devices); |
| 338 | return ERR_PTR(-ENOMEM); |
| 339 | } |
| 340 | |
| 341 | int btrfs_close_extra_devices(struct btrfs_fs_devices *fs_devices) |
| 342 | { |
| 343 | struct btrfs_device *device, *next; |
| 344 | |
| 345 | mutex_lock(&uuid_mutex); |
| 346 | again: |
| 347 | list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) { |
| 348 | if (device->in_fs_metadata) |
| 349 | continue; |
| 350 | |
| 351 | if (device->bdev) { |
| 352 | close_bdev_exclusive(device->bdev, device->mode); |
| 353 | device->bdev = NULL; |
| 354 | fs_devices->open_devices--; |
| 355 | } |
| 356 | if (device->writeable) { |
| 357 | list_del_init(&device->dev_alloc_list); |
| 358 | device->writeable = 0; |
| 359 | fs_devices->rw_devices--; |
| 360 | } |
| 361 | list_del_init(&device->dev_list); |
| 362 | fs_devices->num_devices--; |
| 363 | kfree(device->name); |
| 364 | kfree(device); |
| 365 | } |
| 366 | |
| 367 | if (fs_devices->seed) { |
| 368 | fs_devices = fs_devices->seed; |
| 369 | goto again; |
| 370 | } |
| 371 | |
| 372 | mutex_unlock(&uuid_mutex); |
| 373 | return 0; |
| 374 | } |
| 375 | |
| 376 | static int __btrfs_close_devices(struct btrfs_fs_devices *fs_devices) |
| 377 | { |
| 378 | struct btrfs_device *device; |
| 379 | |
| 380 | if (--fs_devices->opened > 0) |
| 381 | return 0; |
| 382 | |
| 383 | list_for_each_entry(device, &fs_devices->devices, dev_list) { |
| 384 | if (device->bdev) { |
| 385 | close_bdev_exclusive(device->bdev, device->mode); |
| 386 | fs_devices->open_devices--; |
| 387 | } |
| 388 | if (device->writeable) { |
| 389 | list_del_init(&device->dev_alloc_list); |
| 390 | fs_devices->rw_devices--; |
| 391 | } |
| 392 | |
| 393 | device->bdev = NULL; |
| 394 | device->writeable = 0; |
| 395 | device->in_fs_metadata = 0; |
| 396 | } |
| 397 | WARN_ON(fs_devices->open_devices); |
| 398 | WARN_ON(fs_devices->rw_devices); |
| 399 | fs_devices->opened = 0; |
| 400 | fs_devices->seeding = 0; |
| 401 | |
| 402 | return 0; |
| 403 | } |
| 404 | |
| 405 | int btrfs_close_devices(struct btrfs_fs_devices *fs_devices) |
| 406 | { |
| 407 | struct btrfs_fs_devices *seed_devices = NULL; |
| 408 | int ret; |
| 409 | |
| 410 | mutex_lock(&uuid_mutex); |
| 411 | ret = __btrfs_close_devices(fs_devices); |
| 412 | if (!fs_devices->opened) { |
| 413 | seed_devices = fs_devices->seed; |
| 414 | fs_devices->seed = NULL; |
| 415 | } |
| 416 | mutex_unlock(&uuid_mutex); |
| 417 | |
| 418 | while (seed_devices) { |
| 419 | fs_devices = seed_devices; |
| 420 | seed_devices = fs_devices->seed; |
| 421 | __btrfs_close_devices(fs_devices); |
| 422 | free_fs_devices(fs_devices); |
| 423 | } |
| 424 | return ret; |
| 425 | } |
| 426 | |
| 427 | static int __btrfs_open_devices(struct btrfs_fs_devices *fs_devices, |
| 428 | fmode_t flags, void *holder) |
| 429 | { |
| 430 | struct block_device *bdev; |
| 431 | struct list_head *head = &fs_devices->devices; |
| 432 | struct btrfs_device *device; |
| 433 | struct block_device *latest_bdev = NULL; |
| 434 | struct buffer_head *bh; |
| 435 | struct btrfs_super_block *disk_super; |
| 436 | u64 latest_devid = 0; |
| 437 | u64 latest_transid = 0; |
| 438 | u64 devid; |
| 439 | int seeding = 1; |
| 440 | int ret = 0; |
| 441 | |
| 442 | list_for_each_entry(device, head, dev_list) { |
| 443 | if (device->bdev) |
| 444 | continue; |
| 445 | if (!device->name) |
| 446 | continue; |
| 447 | |
| 448 | bdev = open_bdev_exclusive(device->name, flags, holder); |
| 449 | if (IS_ERR(bdev)) { |
| 450 | printk(KERN_INFO "open %s failed\n", device->name); |
| 451 | goto error; |
| 452 | } |
| 453 | set_blocksize(bdev, 4096); |
| 454 | |
| 455 | bh = btrfs_read_dev_super(bdev); |
| 456 | if (!bh) |
| 457 | goto error_close; |
| 458 | |
| 459 | disk_super = (struct btrfs_super_block *)bh->b_data; |
| 460 | devid = le64_to_cpu(disk_super->dev_item.devid); |
| 461 | if (devid != device->devid) |
| 462 | goto error_brelse; |
| 463 | |
| 464 | if (memcmp(device->uuid, disk_super->dev_item.uuid, |
| 465 | BTRFS_UUID_SIZE)) |
| 466 | goto error_brelse; |
| 467 | |
| 468 | device->generation = btrfs_super_generation(disk_super); |
| 469 | if (!latest_transid || device->generation > latest_transid) { |
| 470 | latest_devid = devid; |
| 471 | latest_transid = device->generation; |
| 472 | latest_bdev = bdev; |
| 473 | } |
| 474 | |
| 475 | if (btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_SEEDING) { |
| 476 | device->writeable = 0; |
| 477 | } else { |
| 478 | device->writeable = !bdev_read_only(bdev); |
| 479 | seeding = 0; |
| 480 | } |
| 481 | |
| 482 | device->bdev = bdev; |
| 483 | device->in_fs_metadata = 0; |
| 484 | device->mode = flags; |
| 485 | |
| 486 | fs_devices->open_devices++; |
| 487 | if (device->writeable) { |
| 488 | fs_devices->rw_devices++; |
| 489 | list_add(&device->dev_alloc_list, |
| 490 | &fs_devices->alloc_list); |
| 491 | } |
| 492 | continue; |
| 493 | |
| 494 | error_brelse: |
| 495 | brelse(bh); |
| 496 | error_close: |
| 497 | close_bdev_exclusive(bdev, FMODE_READ); |
| 498 | error: |
| 499 | continue; |
| 500 | } |
| 501 | if (fs_devices->open_devices == 0) { |
| 502 | ret = -EIO; |
| 503 | goto out; |
| 504 | } |
| 505 | fs_devices->seeding = seeding; |
| 506 | fs_devices->opened = 1; |
| 507 | fs_devices->latest_bdev = latest_bdev; |
| 508 | fs_devices->latest_devid = latest_devid; |
| 509 | fs_devices->latest_trans = latest_transid; |
| 510 | fs_devices->total_rw_bytes = 0; |
| 511 | out: |
| 512 | return ret; |
| 513 | } |
| 514 | |
| 515 | int btrfs_open_devices(struct btrfs_fs_devices *fs_devices, |
| 516 | fmode_t flags, void *holder) |
| 517 | { |
| 518 | int ret; |
| 519 | |
| 520 | mutex_lock(&uuid_mutex); |
| 521 | if (fs_devices->opened) { |
| 522 | fs_devices->opened++; |
| 523 | ret = 0; |
| 524 | } else { |
| 525 | ret = __btrfs_open_devices(fs_devices, flags, holder); |
| 526 | } |
| 527 | mutex_unlock(&uuid_mutex); |
| 528 | return ret; |
| 529 | } |
| 530 | |
| 531 | int btrfs_scan_one_device(const char *path, fmode_t flags, void *holder, |
| 532 | struct btrfs_fs_devices **fs_devices_ret) |
| 533 | { |
| 534 | struct btrfs_super_block *disk_super; |
| 535 | struct block_device *bdev; |
| 536 | struct buffer_head *bh; |
| 537 | int ret; |
| 538 | u64 devid; |
| 539 | u64 transid; |
| 540 | |
| 541 | mutex_lock(&uuid_mutex); |
| 542 | |
| 543 | bdev = open_bdev_exclusive(path, flags, holder); |
| 544 | |
| 545 | if (IS_ERR(bdev)) { |
| 546 | ret = PTR_ERR(bdev); |
| 547 | goto error; |
| 548 | } |
| 549 | |
| 550 | ret = set_blocksize(bdev, 4096); |
| 551 | if (ret) |
| 552 | goto error_close; |
| 553 | bh = btrfs_read_dev_super(bdev); |
| 554 | if (!bh) { |
| 555 | ret = -EIO; |
| 556 | goto error_close; |
| 557 | } |
| 558 | disk_super = (struct btrfs_super_block *)bh->b_data; |
| 559 | devid = le64_to_cpu(disk_super->dev_item.devid); |
| 560 | transid = btrfs_super_generation(disk_super); |
| 561 | if (disk_super->label[0]) |
| 562 | printk(KERN_INFO "device label %s ", disk_super->label); |
| 563 | else { |
| 564 | /* FIXME, make a readl uuid parser */ |
| 565 | printk(KERN_INFO "device fsid %llx-%llx ", |
| 566 | *(unsigned long long *)disk_super->fsid, |
| 567 | *(unsigned long long *)(disk_super->fsid + 8)); |
| 568 | } |
| 569 | printk(KERN_CONT "devid %llu transid %llu %s\n", |
| 570 | (unsigned long long)devid, (unsigned long long)transid, path); |
| 571 | ret = device_list_add(path, disk_super, devid, fs_devices_ret); |
| 572 | |
| 573 | brelse(bh); |
| 574 | error_close: |
| 575 | close_bdev_exclusive(bdev, flags); |
| 576 | error: |
| 577 | mutex_unlock(&uuid_mutex); |
| 578 | return ret; |
| 579 | } |
| 580 | |
| 581 | /* |
| 582 | * this uses a pretty simple search, the expectation is that it is |
| 583 | * called very infrequently and that a given device has a small number |
| 584 | * of extents |
| 585 | */ |
| 586 | static noinline int find_free_dev_extent(struct btrfs_trans_handle *trans, |
| 587 | struct btrfs_device *device, |
| 588 | u64 num_bytes, u64 *start) |
| 589 | { |
| 590 | struct btrfs_key key; |
| 591 | struct btrfs_root *root = device->dev_root; |
| 592 | struct btrfs_dev_extent *dev_extent = NULL; |
| 593 | struct btrfs_path *path; |
| 594 | u64 hole_size = 0; |
| 595 | u64 last_byte = 0; |
| 596 | u64 search_start = 0; |
| 597 | u64 search_end = device->total_bytes; |
| 598 | int ret; |
| 599 | int slot = 0; |
| 600 | int start_found; |
| 601 | struct extent_buffer *l; |
| 602 | |
| 603 | path = btrfs_alloc_path(); |
| 604 | if (!path) |
| 605 | return -ENOMEM; |
| 606 | path->reada = 2; |
| 607 | start_found = 0; |
| 608 | |
| 609 | /* FIXME use last free of some kind */ |
| 610 | |
| 611 | /* we don't want to overwrite the superblock on the drive, |
| 612 | * so we make sure to start at an offset of at least 1MB |
| 613 | */ |
| 614 | search_start = max((u64)1024 * 1024, search_start); |
| 615 | |
| 616 | if (root->fs_info->alloc_start + num_bytes <= device->total_bytes) |
| 617 | search_start = max(root->fs_info->alloc_start, search_start); |
| 618 | |
| 619 | key.objectid = device->devid; |
| 620 | key.offset = search_start; |
| 621 | key.type = BTRFS_DEV_EXTENT_KEY; |
| 622 | ret = btrfs_search_slot(trans, root, &key, path, 0, 0); |
| 623 | if (ret < 0) |
| 624 | goto error; |
| 625 | ret = btrfs_previous_item(root, path, 0, key.type); |
| 626 | if (ret < 0) |
| 627 | goto error; |
| 628 | l = path->nodes[0]; |
| 629 | btrfs_item_key_to_cpu(l, &key, path->slots[0]); |
| 630 | while (1) { |
| 631 | l = path->nodes[0]; |
| 632 | slot = path->slots[0]; |
| 633 | if (slot >= btrfs_header_nritems(l)) { |
| 634 | ret = btrfs_next_leaf(root, path); |
| 635 | if (ret == 0) |
| 636 | continue; |
| 637 | if (ret < 0) |
| 638 | goto error; |
| 639 | no_more_items: |
| 640 | if (!start_found) { |
| 641 | if (search_start >= search_end) { |
| 642 | ret = -ENOSPC; |
| 643 | goto error; |
| 644 | } |
| 645 | *start = search_start; |
| 646 | start_found = 1; |
| 647 | goto check_pending; |
| 648 | } |
| 649 | *start = last_byte > search_start ? |
| 650 | last_byte : search_start; |
| 651 | if (search_end <= *start) { |
| 652 | ret = -ENOSPC; |
| 653 | goto error; |
| 654 | } |
| 655 | goto check_pending; |
| 656 | } |
| 657 | btrfs_item_key_to_cpu(l, &key, slot); |
| 658 | |
| 659 | if (key.objectid < device->devid) |
| 660 | goto next; |
| 661 | |
| 662 | if (key.objectid > device->devid) |
| 663 | goto no_more_items; |
| 664 | |
| 665 | if (key.offset >= search_start && key.offset > last_byte && |
| 666 | start_found) { |
| 667 | if (last_byte < search_start) |
| 668 | last_byte = search_start; |
| 669 | hole_size = key.offset - last_byte; |
| 670 | if (key.offset > last_byte && |
| 671 | hole_size >= num_bytes) { |
| 672 | *start = last_byte; |
| 673 | goto check_pending; |
| 674 | } |
| 675 | } |
| 676 | if (btrfs_key_type(&key) != BTRFS_DEV_EXTENT_KEY) |
| 677 | goto next; |
| 678 | |
| 679 | start_found = 1; |
| 680 | dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent); |
| 681 | last_byte = key.offset + btrfs_dev_extent_length(l, dev_extent); |
| 682 | next: |
| 683 | path->slots[0]++; |
| 684 | cond_resched(); |
| 685 | } |
| 686 | check_pending: |
| 687 | /* we have to make sure we didn't find an extent that has already |
| 688 | * been allocated by the map tree or the original allocation |
| 689 | */ |
| 690 | BUG_ON(*start < search_start); |
| 691 | |
| 692 | if (*start + num_bytes > search_end) { |
| 693 | ret = -ENOSPC; |
| 694 | goto error; |
| 695 | } |
| 696 | /* check for pending inserts here */ |
| 697 | ret = 0; |
| 698 | |
| 699 | error: |
| 700 | btrfs_free_path(path); |
| 701 | return ret; |
| 702 | } |
| 703 | |
| 704 | static int btrfs_free_dev_extent(struct btrfs_trans_handle *trans, |
| 705 | struct btrfs_device *device, |
| 706 | u64 start) |
| 707 | { |
| 708 | int ret; |
| 709 | struct btrfs_path *path; |
| 710 | struct btrfs_root *root = device->dev_root; |
| 711 | struct btrfs_key key; |
| 712 | struct btrfs_key found_key; |
| 713 | struct extent_buffer *leaf = NULL; |
| 714 | struct btrfs_dev_extent *extent = NULL; |
| 715 | |
| 716 | path = btrfs_alloc_path(); |
| 717 | if (!path) |
| 718 | return -ENOMEM; |
| 719 | |
| 720 | key.objectid = device->devid; |
| 721 | key.offset = start; |
| 722 | key.type = BTRFS_DEV_EXTENT_KEY; |
| 723 | |
| 724 | ret = btrfs_search_slot(trans, root, &key, path, -1, 1); |
| 725 | if (ret > 0) { |
| 726 | ret = btrfs_previous_item(root, path, key.objectid, |
| 727 | BTRFS_DEV_EXTENT_KEY); |
| 728 | BUG_ON(ret); |
| 729 | leaf = path->nodes[0]; |
| 730 | btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); |
| 731 | extent = btrfs_item_ptr(leaf, path->slots[0], |
| 732 | struct btrfs_dev_extent); |
| 733 | BUG_ON(found_key.offset > start || found_key.offset + |
| 734 | btrfs_dev_extent_length(leaf, extent) < start); |
| 735 | ret = 0; |
| 736 | } else if (ret == 0) { |
| 737 | leaf = path->nodes[0]; |
| 738 | extent = btrfs_item_ptr(leaf, path->slots[0], |
| 739 | struct btrfs_dev_extent); |
| 740 | } |
| 741 | BUG_ON(ret); |
| 742 | |
| 743 | if (device->bytes_used > 0) |
| 744 | device->bytes_used -= btrfs_dev_extent_length(leaf, extent); |
| 745 | ret = btrfs_del_item(trans, root, path); |
| 746 | BUG_ON(ret); |
| 747 | |
| 748 | btrfs_free_path(path); |
| 749 | return ret; |
| 750 | } |
| 751 | |
| 752 | int btrfs_alloc_dev_extent(struct btrfs_trans_handle *trans, |
| 753 | struct btrfs_device *device, |
| 754 | u64 chunk_tree, u64 chunk_objectid, |
| 755 | u64 chunk_offset, u64 start, u64 num_bytes) |
| 756 | { |
| 757 | int ret; |
| 758 | struct btrfs_path *path; |
| 759 | struct btrfs_root *root = device->dev_root; |
| 760 | struct btrfs_dev_extent *extent; |
| 761 | struct extent_buffer *leaf; |
| 762 | struct btrfs_key key; |
| 763 | |
| 764 | WARN_ON(!device->in_fs_metadata); |
| 765 | path = btrfs_alloc_path(); |
| 766 | if (!path) |
| 767 | return -ENOMEM; |
| 768 | |
| 769 | key.objectid = device->devid; |
| 770 | key.offset = start; |
| 771 | key.type = BTRFS_DEV_EXTENT_KEY; |
| 772 | ret = btrfs_insert_empty_item(trans, root, path, &key, |
| 773 | sizeof(*extent)); |
| 774 | BUG_ON(ret); |
| 775 | |
| 776 | leaf = path->nodes[0]; |
| 777 | extent = btrfs_item_ptr(leaf, path->slots[0], |
| 778 | struct btrfs_dev_extent); |
| 779 | btrfs_set_dev_extent_chunk_tree(leaf, extent, chunk_tree); |
| 780 | btrfs_set_dev_extent_chunk_objectid(leaf, extent, chunk_objectid); |
| 781 | btrfs_set_dev_extent_chunk_offset(leaf, extent, chunk_offset); |
| 782 | |
| 783 | write_extent_buffer(leaf, root->fs_info->chunk_tree_uuid, |
| 784 | (unsigned long)btrfs_dev_extent_chunk_tree_uuid(extent), |
| 785 | BTRFS_UUID_SIZE); |
| 786 | |
| 787 | btrfs_set_dev_extent_length(leaf, extent, num_bytes); |
| 788 | btrfs_mark_buffer_dirty(leaf); |
| 789 | btrfs_free_path(path); |
| 790 | return ret; |
| 791 | } |
| 792 | |
| 793 | static noinline int find_next_chunk(struct btrfs_root *root, |
| 794 | u64 objectid, u64 *offset) |
| 795 | { |
| 796 | struct btrfs_path *path; |
| 797 | int ret; |
| 798 | struct btrfs_key key; |
| 799 | struct btrfs_chunk *chunk; |
| 800 | struct btrfs_key found_key; |
| 801 | |
| 802 | path = btrfs_alloc_path(); |
| 803 | BUG_ON(!path); |
| 804 | |
| 805 | key.objectid = objectid; |
| 806 | key.offset = (u64)-1; |
| 807 | key.type = BTRFS_CHUNK_ITEM_KEY; |
| 808 | |
| 809 | ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); |
| 810 | if (ret < 0) |
| 811 | goto error; |
| 812 | |
| 813 | BUG_ON(ret == 0); |
| 814 | |
| 815 | ret = btrfs_previous_item(root, path, 0, BTRFS_CHUNK_ITEM_KEY); |
| 816 | if (ret) { |
| 817 | *offset = 0; |
| 818 | } else { |
| 819 | btrfs_item_key_to_cpu(path->nodes[0], &found_key, |
| 820 | path->slots[0]); |
| 821 | if (found_key.objectid != objectid) |
| 822 | *offset = 0; |
| 823 | else { |
| 824 | chunk = btrfs_item_ptr(path->nodes[0], path->slots[0], |
| 825 | struct btrfs_chunk); |
| 826 | *offset = found_key.offset + |
| 827 | btrfs_chunk_length(path->nodes[0], chunk); |
| 828 | } |
| 829 | } |
| 830 | ret = 0; |
| 831 | error: |
| 832 | btrfs_free_path(path); |
| 833 | return ret; |
| 834 | } |
| 835 | |
| 836 | static noinline int find_next_devid(struct btrfs_root *root, u64 *objectid) |
| 837 | { |
| 838 | int ret; |
| 839 | struct btrfs_key key; |
| 840 | struct btrfs_key found_key; |
| 841 | struct btrfs_path *path; |
| 842 | |
| 843 | root = root->fs_info->chunk_root; |
| 844 | |
| 845 | path = btrfs_alloc_path(); |
| 846 | if (!path) |
| 847 | return -ENOMEM; |
| 848 | |
| 849 | key.objectid = BTRFS_DEV_ITEMS_OBJECTID; |
| 850 | key.type = BTRFS_DEV_ITEM_KEY; |
| 851 | key.offset = (u64)-1; |
| 852 | |
| 853 | ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); |
| 854 | if (ret < 0) |
| 855 | goto error; |
| 856 | |
| 857 | BUG_ON(ret == 0); |
| 858 | |
| 859 | ret = btrfs_previous_item(root, path, BTRFS_DEV_ITEMS_OBJECTID, |
| 860 | BTRFS_DEV_ITEM_KEY); |
| 861 | if (ret) { |
| 862 | *objectid = 1; |
| 863 | } else { |
| 864 | btrfs_item_key_to_cpu(path->nodes[0], &found_key, |
| 865 | path->slots[0]); |
| 866 | *objectid = found_key.offset + 1; |
| 867 | } |
| 868 | ret = 0; |
| 869 | error: |
| 870 | btrfs_free_path(path); |
| 871 | return ret; |
| 872 | } |
| 873 | |
| 874 | /* |
| 875 | * the device information is stored in the chunk root |
| 876 | * the btrfs_device struct should be fully filled in |
| 877 | */ |
| 878 | int btrfs_add_device(struct btrfs_trans_handle *trans, |
| 879 | struct btrfs_root *root, |
| 880 | struct btrfs_device *device) |
| 881 | { |
| 882 | int ret; |
| 883 | struct btrfs_path *path; |
| 884 | struct btrfs_dev_item *dev_item; |
| 885 | struct extent_buffer *leaf; |
| 886 | struct btrfs_key key; |
| 887 | unsigned long ptr; |
| 888 | |
| 889 | root = root->fs_info->chunk_root; |
| 890 | |
| 891 | path = btrfs_alloc_path(); |
| 892 | if (!path) |
| 893 | return -ENOMEM; |
| 894 | |
| 895 | key.objectid = BTRFS_DEV_ITEMS_OBJECTID; |
| 896 | key.type = BTRFS_DEV_ITEM_KEY; |
| 897 | key.offset = device->devid; |
| 898 | |
| 899 | ret = btrfs_insert_empty_item(trans, root, path, &key, |
| 900 | sizeof(*dev_item)); |
| 901 | if (ret) |
| 902 | goto out; |
| 903 | |
| 904 | leaf = path->nodes[0]; |
| 905 | dev_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dev_item); |
| 906 | |
| 907 | btrfs_set_device_id(leaf, dev_item, device->devid); |
| 908 | btrfs_set_device_generation(leaf, dev_item, 0); |
| 909 | btrfs_set_device_type(leaf, dev_item, device->type); |
| 910 | btrfs_set_device_io_align(leaf, dev_item, device->io_align); |
| 911 | btrfs_set_device_io_width(leaf, dev_item, device->io_width); |
| 912 | btrfs_set_device_sector_size(leaf, dev_item, device->sector_size); |
| 913 | btrfs_set_device_total_bytes(leaf, dev_item, device->total_bytes); |
| 914 | btrfs_set_device_bytes_used(leaf, dev_item, device->bytes_used); |
| 915 | btrfs_set_device_group(leaf, dev_item, 0); |
| 916 | btrfs_set_device_seek_speed(leaf, dev_item, 0); |
| 917 | btrfs_set_device_bandwidth(leaf, dev_item, 0); |
| 918 | btrfs_set_device_start_offset(leaf, dev_item, 0); |
| 919 | |
| 920 | ptr = (unsigned long)btrfs_device_uuid(dev_item); |
| 921 | write_extent_buffer(leaf, device->uuid, ptr, BTRFS_UUID_SIZE); |
| 922 | ptr = (unsigned long)btrfs_device_fsid(dev_item); |
| 923 | write_extent_buffer(leaf, root->fs_info->fsid, ptr, BTRFS_UUID_SIZE); |
| 924 | btrfs_mark_buffer_dirty(leaf); |
| 925 | |
| 926 | ret = 0; |
| 927 | out: |
| 928 | btrfs_free_path(path); |
| 929 | return ret; |
| 930 | } |
| 931 | |
| 932 | static int btrfs_rm_dev_item(struct btrfs_root *root, |
| 933 | struct btrfs_device *device) |
| 934 | { |
| 935 | int ret; |
| 936 | struct btrfs_path *path; |
| 937 | struct btrfs_key key; |
| 938 | struct btrfs_trans_handle *trans; |
| 939 | |
| 940 | root = root->fs_info->chunk_root; |
| 941 | |
| 942 | path = btrfs_alloc_path(); |
| 943 | if (!path) |
| 944 | return -ENOMEM; |
| 945 | |
| 946 | trans = btrfs_start_transaction(root, 1); |
| 947 | key.objectid = BTRFS_DEV_ITEMS_OBJECTID; |
| 948 | key.type = BTRFS_DEV_ITEM_KEY; |
| 949 | key.offset = device->devid; |
| 950 | lock_chunks(root); |
| 951 | |
| 952 | ret = btrfs_search_slot(trans, root, &key, path, -1, 1); |
| 953 | if (ret < 0) |
| 954 | goto out; |
| 955 | |
| 956 | if (ret > 0) { |
| 957 | ret = -ENOENT; |
| 958 | goto out; |
| 959 | } |
| 960 | |
| 961 | ret = btrfs_del_item(trans, root, path); |
| 962 | if (ret) |
| 963 | goto out; |
| 964 | out: |
| 965 | btrfs_free_path(path); |
| 966 | unlock_chunks(root); |
| 967 | btrfs_commit_transaction(trans, root); |
| 968 | return ret; |
| 969 | } |
| 970 | |
| 971 | int btrfs_rm_device(struct btrfs_root *root, char *device_path) |
| 972 | { |
| 973 | struct btrfs_device *device; |
| 974 | struct btrfs_device *next_device; |
| 975 | struct block_device *bdev; |
| 976 | struct buffer_head *bh = NULL; |
| 977 | struct btrfs_super_block *disk_super; |
| 978 | u64 all_avail; |
| 979 | u64 devid; |
| 980 | u64 num_devices; |
| 981 | u8 *dev_uuid; |
| 982 | int ret = 0; |
| 983 | |
| 984 | mutex_lock(&uuid_mutex); |
| 985 | mutex_lock(&root->fs_info->volume_mutex); |
| 986 | |
| 987 | all_avail = root->fs_info->avail_data_alloc_bits | |
| 988 | root->fs_info->avail_system_alloc_bits | |
| 989 | root->fs_info->avail_metadata_alloc_bits; |
| 990 | |
| 991 | if ((all_avail & BTRFS_BLOCK_GROUP_RAID10) && |
| 992 | root->fs_info->fs_devices->rw_devices <= 4) { |
| 993 | printk(KERN_ERR "btrfs: unable to go below four devices " |
| 994 | "on raid10\n"); |
| 995 | ret = -EINVAL; |
| 996 | goto out; |
| 997 | } |
| 998 | |
| 999 | if ((all_avail & BTRFS_BLOCK_GROUP_RAID1) && |
| 1000 | root->fs_info->fs_devices->rw_devices <= 2) { |
| 1001 | printk(KERN_ERR "btrfs: unable to go below two " |
| 1002 | "devices on raid1\n"); |
| 1003 | ret = -EINVAL; |
| 1004 | goto out; |
| 1005 | } |
| 1006 | |
| 1007 | if (strcmp(device_path, "missing") == 0) { |
| 1008 | struct list_head *devices; |
| 1009 | struct btrfs_device *tmp; |
| 1010 | |
| 1011 | device = NULL; |
| 1012 | devices = &root->fs_info->fs_devices->devices; |
| 1013 | list_for_each_entry(tmp, devices, dev_list) { |
| 1014 | if (tmp->in_fs_metadata && !tmp->bdev) { |
| 1015 | device = tmp; |
| 1016 | break; |
| 1017 | } |
| 1018 | } |
| 1019 | bdev = NULL; |
| 1020 | bh = NULL; |
| 1021 | disk_super = NULL; |
| 1022 | if (!device) { |
| 1023 | printk(KERN_ERR "btrfs: no missing devices found to " |
| 1024 | "remove\n"); |
| 1025 | goto out; |
| 1026 | } |
| 1027 | } else { |
| 1028 | bdev = open_bdev_exclusive(device_path, FMODE_READ, |
| 1029 | root->fs_info->bdev_holder); |
| 1030 | if (IS_ERR(bdev)) { |
| 1031 | ret = PTR_ERR(bdev); |
| 1032 | goto out; |
| 1033 | } |
| 1034 | |
| 1035 | set_blocksize(bdev, 4096); |
| 1036 | bh = btrfs_read_dev_super(bdev); |
| 1037 | if (!bh) { |
| 1038 | ret = -EIO; |
| 1039 | goto error_close; |
| 1040 | } |
| 1041 | disk_super = (struct btrfs_super_block *)bh->b_data; |
| 1042 | devid = le64_to_cpu(disk_super->dev_item.devid); |
| 1043 | dev_uuid = disk_super->dev_item.uuid; |
| 1044 | device = btrfs_find_device(root, devid, dev_uuid, |
| 1045 | disk_super->fsid); |
| 1046 | if (!device) { |
| 1047 | ret = -ENOENT; |
| 1048 | goto error_brelse; |
| 1049 | } |
| 1050 | } |
| 1051 | |
| 1052 | if (device->writeable && root->fs_info->fs_devices->rw_devices == 1) { |
| 1053 | printk(KERN_ERR "btrfs: unable to remove the only writeable " |
| 1054 | "device\n"); |
| 1055 | ret = -EINVAL; |
| 1056 | goto error_brelse; |
| 1057 | } |
| 1058 | |
| 1059 | if (device->writeable) { |
| 1060 | list_del_init(&device->dev_alloc_list); |
| 1061 | root->fs_info->fs_devices->rw_devices--; |
| 1062 | } |
| 1063 | |
| 1064 | ret = btrfs_shrink_device(device, 0); |
| 1065 | if (ret) |
| 1066 | goto error_brelse; |
| 1067 | |
| 1068 | ret = btrfs_rm_dev_item(root->fs_info->chunk_root, device); |
| 1069 | if (ret) |
| 1070 | goto error_brelse; |
| 1071 | |
| 1072 | device->in_fs_metadata = 0; |
| 1073 | list_del_init(&device->dev_list); |
| 1074 | device->fs_devices->num_devices--; |
| 1075 | |
| 1076 | next_device = list_entry(root->fs_info->fs_devices->devices.next, |
| 1077 | struct btrfs_device, dev_list); |
| 1078 | if (device->bdev == root->fs_info->sb->s_bdev) |
| 1079 | root->fs_info->sb->s_bdev = next_device->bdev; |
| 1080 | if (device->bdev == root->fs_info->fs_devices->latest_bdev) |
| 1081 | root->fs_info->fs_devices->latest_bdev = next_device->bdev; |
| 1082 | |
| 1083 | if (device->bdev) { |
| 1084 | close_bdev_exclusive(device->bdev, device->mode); |
| 1085 | device->bdev = NULL; |
| 1086 | device->fs_devices->open_devices--; |
| 1087 | } |
| 1088 | |
| 1089 | num_devices = btrfs_super_num_devices(&root->fs_info->super_copy) - 1; |
| 1090 | btrfs_set_super_num_devices(&root->fs_info->super_copy, num_devices); |
| 1091 | |
| 1092 | if (device->fs_devices->open_devices == 0) { |
| 1093 | struct btrfs_fs_devices *fs_devices; |
| 1094 | fs_devices = root->fs_info->fs_devices; |
| 1095 | while (fs_devices) { |
| 1096 | if (fs_devices->seed == device->fs_devices) |
| 1097 | break; |
| 1098 | fs_devices = fs_devices->seed; |
| 1099 | } |
| 1100 | fs_devices->seed = device->fs_devices->seed; |
| 1101 | device->fs_devices->seed = NULL; |
| 1102 | __btrfs_close_devices(device->fs_devices); |
| 1103 | free_fs_devices(device->fs_devices); |
| 1104 | } |
| 1105 | |
| 1106 | /* |
| 1107 | * at this point, the device is zero sized. We want to |
| 1108 | * remove it from the devices list and zero out the old super |
| 1109 | */ |
| 1110 | if (device->writeable) { |
| 1111 | /* make sure this device isn't detected as part of |
| 1112 | * the FS anymore |
| 1113 | */ |
| 1114 | memset(&disk_super->magic, 0, sizeof(disk_super->magic)); |
| 1115 | set_buffer_dirty(bh); |
| 1116 | sync_dirty_buffer(bh); |
| 1117 | } |
| 1118 | |
| 1119 | kfree(device->name); |
| 1120 | kfree(device); |
| 1121 | ret = 0; |
| 1122 | |
| 1123 | error_brelse: |
| 1124 | brelse(bh); |
| 1125 | error_close: |
| 1126 | if (bdev) |
| 1127 | close_bdev_exclusive(bdev, FMODE_READ); |
| 1128 | out: |
| 1129 | mutex_unlock(&root->fs_info->volume_mutex); |
| 1130 | mutex_unlock(&uuid_mutex); |
| 1131 | return ret; |
| 1132 | } |
| 1133 | |
| 1134 | /* |
| 1135 | * does all the dirty work required for changing file system's UUID. |
| 1136 | */ |
| 1137 | static int btrfs_prepare_sprout(struct btrfs_trans_handle *trans, |
| 1138 | struct btrfs_root *root) |
| 1139 | { |
| 1140 | struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices; |
| 1141 | struct btrfs_fs_devices *old_devices; |
| 1142 | struct btrfs_fs_devices *seed_devices; |
| 1143 | struct btrfs_super_block *disk_super = &root->fs_info->super_copy; |
| 1144 | struct btrfs_device *device; |
| 1145 | u64 super_flags; |
| 1146 | |
| 1147 | BUG_ON(!mutex_is_locked(&uuid_mutex)); |
| 1148 | if (!fs_devices->seeding) |
| 1149 | return -EINVAL; |
| 1150 | |
| 1151 | seed_devices = kzalloc(sizeof(*fs_devices), GFP_NOFS); |
| 1152 | if (!seed_devices) |
| 1153 | return -ENOMEM; |
| 1154 | |
| 1155 | old_devices = clone_fs_devices(fs_devices); |
| 1156 | if (IS_ERR(old_devices)) { |
| 1157 | kfree(seed_devices); |
| 1158 | return PTR_ERR(old_devices); |
| 1159 | } |
| 1160 | |
| 1161 | list_add(&old_devices->list, &fs_uuids); |
| 1162 | |
| 1163 | memcpy(seed_devices, fs_devices, sizeof(*seed_devices)); |
| 1164 | seed_devices->opened = 1; |
| 1165 | INIT_LIST_HEAD(&seed_devices->devices); |
| 1166 | INIT_LIST_HEAD(&seed_devices->alloc_list); |
| 1167 | list_splice_init(&fs_devices->devices, &seed_devices->devices); |
| 1168 | list_splice_init(&fs_devices->alloc_list, &seed_devices->alloc_list); |
| 1169 | list_for_each_entry(device, &seed_devices->devices, dev_list) { |
| 1170 | device->fs_devices = seed_devices; |
| 1171 | } |
| 1172 | |
| 1173 | fs_devices->seeding = 0; |
| 1174 | fs_devices->num_devices = 0; |
| 1175 | fs_devices->open_devices = 0; |
| 1176 | fs_devices->seed = seed_devices; |
| 1177 | |
| 1178 | generate_random_uuid(fs_devices->fsid); |
| 1179 | memcpy(root->fs_info->fsid, fs_devices->fsid, BTRFS_FSID_SIZE); |
| 1180 | memcpy(disk_super->fsid, fs_devices->fsid, BTRFS_FSID_SIZE); |
| 1181 | super_flags = btrfs_super_flags(disk_super) & |
| 1182 | ~BTRFS_SUPER_FLAG_SEEDING; |
| 1183 | btrfs_set_super_flags(disk_super, super_flags); |
| 1184 | |
| 1185 | return 0; |
| 1186 | } |
| 1187 | |
| 1188 | /* |
| 1189 | * strore the expected generation for seed devices in device items. |
| 1190 | */ |
| 1191 | static int btrfs_finish_sprout(struct btrfs_trans_handle *trans, |
| 1192 | struct btrfs_root *root) |
| 1193 | { |
| 1194 | struct btrfs_path *path; |
| 1195 | struct extent_buffer *leaf; |
| 1196 | struct btrfs_dev_item *dev_item; |
| 1197 | struct btrfs_device *device; |
| 1198 | struct btrfs_key key; |
| 1199 | u8 fs_uuid[BTRFS_UUID_SIZE]; |
| 1200 | u8 dev_uuid[BTRFS_UUID_SIZE]; |
| 1201 | u64 devid; |
| 1202 | int ret; |
| 1203 | |
| 1204 | path = btrfs_alloc_path(); |
| 1205 | if (!path) |
| 1206 | return -ENOMEM; |
| 1207 | |
| 1208 | root = root->fs_info->chunk_root; |
| 1209 | key.objectid = BTRFS_DEV_ITEMS_OBJECTID; |
| 1210 | key.offset = 0; |
| 1211 | key.type = BTRFS_DEV_ITEM_KEY; |
| 1212 | |
| 1213 | while (1) { |
| 1214 | ret = btrfs_search_slot(trans, root, &key, path, 0, 1); |
| 1215 | if (ret < 0) |
| 1216 | goto error; |
| 1217 | |
| 1218 | leaf = path->nodes[0]; |
| 1219 | next_slot: |
| 1220 | if (path->slots[0] >= btrfs_header_nritems(leaf)) { |
| 1221 | ret = btrfs_next_leaf(root, path); |
| 1222 | if (ret > 0) |
| 1223 | break; |
| 1224 | if (ret < 0) |
| 1225 | goto error; |
| 1226 | leaf = path->nodes[0]; |
| 1227 | btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); |
| 1228 | btrfs_release_path(root, path); |
| 1229 | continue; |
| 1230 | } |
| 1231 | |
| 1232 | btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); |
| 1233 | if (key.objectid != BTRFS_DEV_ITEMS_OBJECTID || |
| 1234 | key.type != BTRFS_DEV_ITEM_KEY) |
| 1235 | break; |
| 1236 | |
| 1237 | dev_item = btrfs_item_ptr(leaf, path->slots[0], |
| 1238 | struct btrfs_dev_item); |
| 1239 | devid = btrfs_device_id(leaf, dev_item); |
| 1240 | read_extent_buffer(leaf, dev_uuid, |
| 1241 | (unsigned long)btrfs_device_uuid(dev_item), |
| 1242 | BTRFS_UUID_SIZE); |
| 1243 | read_extent_buffer(leaf, fs_uuid, |
| 1244 | (unsigned long)btrfs_device_fsid(dev_item), |
| 1245 | BTRFS_UUID_SIZE); |
| 1246 | device = btrfs_find_device(root, devid, dev_uuid, fs_uuid); |
| 1247 | BUG_ON(!device); |
| 1248 | |
| 1249 | if (device->fs_devices->seeding) { |
| 1250 | btrfs_set_device_generation(leaf, dev_item, |
| 1251 | device->generation); |
| 1252 | btrfs_mark_buffer_dirty(leaf); |
| 1253 | } |
| 1254 | |
| 1255 | path->slots[0]++; |
| 1256 | goto next_slot; |
| 1257 | } |
| 1258 | ret = 0; |
| 1259 | error: |
| 1260 | btrfs_free_path(path); |
| 1261 | return ret; |
| 1262 | } |
| 1263 | |
| 1264 | int btrfs_init_new_device(struct btrfs_root *root, char *device_path) |
| 1265 | { |
| 1266 | struct btrfs_trans_handle *trans; |
| 1267 | struct btrfs_device *device; |
| 1268 | struct block_device *bdev; |
| 1269 | struct list_head *devices; |
| 1270 | struct super_block *sb = root->fs_info->sb; |
| 1271 | u64 total_bytes; |
| 1272 | int seeding_dev = 0; |
| 1273 | int ret = 0; |
| 1274 | |
| 1275 | if ((sb->s_flags & MS_RDONLY) && !root->fs_info->fs_devices->seeding) |
| 1276 | return -EINVAL; |
| 1277 | |
| 1278 | bdev = open_bdev_exclusive(device_path, 0, root->fs_info->bdev_holder); |
| 1279 | if (!bdev) |
| 1280 | return -EIO; |
| 1281 | |
| 1282 | if (root->fs_info->fs_devices->seeding) { |
| 1283 | seeding_dev = 1; |
| 1284 | down_write(&sb->s_umount); |
| 1285 | mutex_lock(&uuid_mutex); |
| 1286 | } |
| 1287 | |
| 1288 | filemap_write_and_wait(bdev->bd_inode->i_mapping); |
| 1289 | mutex_lock(&root->fs_info->volume_mutex); |
| 1290 | |
| 1291 | devices = &root->fs_info->fs_devices->devices; |
| 1292 | list_for_each_entry(device, devices, dev_list) { |
| 1293 | if (device->bdev == bdev) { |
| 1294 | ret = -EEXIST; |
| 1295 | goto error; |
| 1296 | } |
| 1297 | } |
| 1298 | |
| 1299 | device = kzalloc(sizeof(*device), GFP_NOFS); |
| 1300 | if (!device) { |
| 1301 | /* we can safely leave the fs_devices entry around */ |
| 1302 | ret = -ENOMEM; |
| 1303 | goto error; |
| 1304 | } |
| 1305 | |
| 1306 | device->name = kstrdup(device_path, GFP_NOFS); |
| 1307 | if (!device->name) { |
| 1308 | kfree(device); |
| 1309 | ret = -ENOMEM; |
| 1310 | goto error; |
| 1311 | } |
| 1312 | |
| 1313 | ret = find_next_devid(root, &device->devid); |
| 1314 | if (ret) { |
| 1315 | kfree(device); |
| 1316 | goto error; |
| 1317 | } |
| 1318 | |
| 1319 | trans = btrfs_start_transaction(root, 1); |
| 1320 | lock_chunks(root); |
| 1321 | |
| 1322 | device->barriers = 1; |
| 1323 | device->writeable = 1; |
| 1324 | device->work.func = pending_bios_fn; |
| 1325 | generate_random_uuid(device->uuid); |
| 1326 | spin_lock_init(&device->io_lock); |
| 1327 | device->generation = trans->transid; |
| 1328 | device->io_width = root->sectorsize; |
| 1329 | device->io_align = root->sectorsize; |
| 1330 | device->sector_size = root->sectorsize; |
| 1331 | device->total_bytes = i_size_read(bdev->bd_inode); |
| 1332 | device->dev_root = root->fs_info->dev_root; |
| 1333 | device->bdev = bdev; |
| 1334 | device->in_fs_metadata = 1; |
| 1335 | device->mode = 0; |
| 1336 | set_blocksize(device->bdev, 4096); |
| 1337 | |
| 1338 | if (seeding_dev) { |
| 1339 | sb->s_flags &= ~MS_RDONLY; |
| 1340 | ret = btrfs_prepare_sprout(trans, root); |
| 1341 | BUG_ON(ret); |
| 1342 | } |
| 1343 | |
| 1344 | device->fs_devices = root->fs_info->fs_devices; |
| 1345 | list_add(&device->dev_list, &root->fs_info->fs_devices->devices); |
| 1346 | list_add(&device->dev_alloc_list, |
| 1347 | &root->fs_info->fs_devices->alloc_list); |
| 1348 | root->fs_info->fs_devices->num_devices++; |
| 1349 | root->fs_info->fs_devices->open_devices++; |
| 1350 | root->fs_info->fs_devices->rw_devices++; |
| 1351 | root->fs_info->fs_devices->total_rw_bytes += device->total_bytes; |
| 1352 | |
| 1353 | total_bytes = btrfs_super_total_bytes(&root->fs_info->super_copy); |
| 1354 | btrfs_set_super_total_bytes(&root->fs_info->super_copy, |
| 1355 | total_bytes + device->total_bytes); |
| 1356 | |
| 1357 | total_bytes = btrfs_super_num_devices(&root->fs_info->super_copy); |
| 1358 | btrfs_set_super_num_devices(&root->fs_info->super_copy, |
| 1359 | total_bytes + 1); |
| 1360 | |
| 1361 | if (seeding_dev) { |
| 1362 | ret = init_first_rw_device(trans, root, device); |
| 1363 | BUG_ON(ret); |
| 1364 | ret = btrfs_finish_sprout(trans, root); |
| 1365 | BUG_ON(ret); |
| 1366 | } else { |
| 1367 | ret = btrfs_add_device(trans, root, device); |
| 1368 | } |
| 1369 | |
| 1370 | unlock_chunks(root); |
| 1371 | btrfs_commit_transaction(trans, root); |
| 1372 | |
| 1373 | if (seeding_dev) { |
| 1374 | mutex_unlock(&uuid_mutex); |
| 1375 | up_write(&sb->s_umount); |
| 1376 | |
| 1377 | ret = btrfs_relocate_sys_chunks(root); |
| 1378 | BUG_ON(ret); |
| 1379 | } |
| 1380 | out: |
| 1381 | mutex_unlock(&root->fs_info->volume_mutex); |
| 1382 | return ret; |
| 1383 | error: |
| 1384 | close_bdev_exclusive(bdev, 0); |
| 1385 | if (seeding_dev) { |
| 1386 | mutex_unlock(&uuid_mutex); |
| 1387 | up_write(&sb->s_umount); |
| 1388 | } |
| 1389 | goto out; |
| 1390 | } |
| 1391 | |
| 1392 | static noinline int btrfs_update_device(struct btrfs_trans_handle *trans, |
| 1393 | struct btrfs_device *device) |
| 1394 | { |
| 1395 | int ret; |
| 1396 | struct btrfs_path *path; |
| 1397 | struct btrfs_root *root; |
| 1398 | struct btrfs_dev_item *dev_item; |
| 1399 | struct extent_buffer *leaf; |
| 1400 | struct btrfs_key key; |
| 1401 | |
| 1402 | root = device->dev_root->fs_info->chunk_root; |
| 1403 | |
| 1404 | path = btrfs_alloc_path(); |
| 1405 | if (!path) |
| 1406 | return -ENOMEM; |
| 1407 | |
| 1408 | key.objectid = BTRFS_DEV_ITEMS_OBJECTID; |
| 1409 | key.type = BTRFS_DEV_ITEM_KEY; |
| 1410 | key.offset = device->devid; |
| 1411 | |
| 1412 | ret = btrfs_search_slot(trans, root, &key, path, 0, 1); |
| 1413 | if (ret < 0) |
| 1414 | goto out; |
| 1415 | |
| 1416 | if (ret > 0) { |
| 1417 | ret = -ENOENT; |
| 1418 | goto out; |
| 1419 | } |
| 1420 | |
| 1421 | leaf = path->nodes[0]; |
| 1422 | dev_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dev_item); |
| 1423 | |
| 1424 | btrfs_set_device_id(leaf, dev_item, device->devid); |
| 1425 | btrfs_set_device_type(leaf, dev_item, device->type); |
| 1426 | btrfs_set_device_io_align(leaf, dev_item, device->io_align); |
| 1427 | btrfs_set_device_io_width(leaf, dev_item, device->io_width); |
| 1428 | btrfs_set_device_sector_size(leaf, dev_item, device->sector_size); |
| 1429 | btrfs_set_device_total_bytes(leaf, dev_item, device->total_bytes); |
| 1430 | btrfs_set_device_bytes_used(leaf, dev_item, device->bytes_used); |
| 1431 | btrfs_mark_buffer_dirty(leaf); |
| 1432 | |
| 1433 | out: |
| 1434 | btrfs_free_path(path); |
| 1435 | return ret; |
| 1436 | } |
| 1437 | |
| 1438 | static int __btrfs_grow_device(struct btrfs_trans_handle *trans, |
| 1439 | struct btrfs_device *device, u64 new_size) |
| 1440 | { |
| 1441 | struct btrfs_super_block *super_copy = |
| 1442 | &device->dev_root->fs_info->super_copy; |
| 1443 | u64 old_total = btrfs_super_total_bytes(super_copy); |
| 1444 | u64 diff = new_size - device->total_bytes; |
| 1445 | |
| 1446 | if (!device->writeable) |
| 1447 | return -EACCES; |
| 1448 | if (new_size <= device->total_bytes) |
| 1449 | return -EINVAL; |
| 1450 | |
| 1451 | btrfs_set_super_total_bytes(super_copy, old_total + diff); |
| 1452 | device->fs_devices->total_rw_bytes += diff; |
| 1453 | |
| 1454 | device->total_bytes = new_size; |
| 1455 | return btrfs_update_device(trans, device); |
| 1456 | } |
| 1457 | |
| 1458 | int btrfs_grow_device(struct btrfs_trans_handle *trans, |
| 1459 | struct btrfs_device *device, u64 new_size) |
| 1460 | { |
| 1461 | int ret; |
| 1462 | lock_chunks(device->dev_root); |
| 1463 | ret = __btrfs_grow_device(trans, device, new_size); |
| 1464 | unlock_chunks(device->dev_root); |
| 1465 | return ret; |
| 1466 | } |
| 1467 | |
| 1468 | static int btrfs_free_chunk(struct btrfs_trans_handle *trans, |
| 1469 | struct btrfs_root *root, |
| 1470 | u64 chunk_tree, u64 chunk_objectid, |
| 1471 | u64 chunk_offset) |
| 1472 | { |
| 1473 | int ret; |
| 1474 | struct btrfs_path *path; |
| 1475 | struct btrfs_key key; |
| 1476 | |
| 1477 | root = root->fs_info->chunk_root; |
| 1478 | path = btrfs_alloc_path(); |
| 1479 | if (!path) |
| 1480 | return -ENOMEM; |
| 1481 | |
| 1482 | key.objectid = chunk_objectid; |
| 1483 | key.offset = chunk_offset; |
| 1484 | key.type = BTRFS_CHUNK_ITEM_KEY; |
| 1485 | |
| 1486 | ret = btrfs_search_slot(trans, root, &key, path, -1, 1); |
| 1487 | BUG_ON(ret); |
| 1488 | |
| 1489 | ret = btrfs_del_item(trans, root, path); |
| 1490 | BUG_ON(ret); |
| 1491 | |
| 1492 | btrfs_free_path(path); |
| 1493 | return 0; |
| 1494 | } |
| 1495 | |
| 1496 | static int btrfs_del_sys_chunk(struct btrfs_root *root, u64 chunk_objectid, u64 |
| 1497 | chunk_offset) |
| 1498 | { |
| 1499 | struct btrfs_super_block *super_copy = &root->fs_info->super_copy; |
| 1500 | struct btrfs_disk_key *disk_key; |
| 1501 | struct btrfs_chunk *chunk; |
| 1502 | u8 *ptr; |
| 1503 | int ret = 0; |
| 1504 | u32 num_stripes; |
| 1505 | u32 array_size; |
| 1506 | u32 len = 0; |
| 1507 | u32 cur; |
| 1508 | struct btrfs_key key; |
| 1509 | |
| 1510 | array_size = btrfs_super_sys_array_size(super_copy); |
| 1511 | |
| 1512 | ptr = super_copy->sys_chunk_array; |
| 1513 | cur = 0; |
| 1514 | |
| 1515 | while (cur < array_size) { |
| 1516 | disk_key = (struct btrfs_disk_key *)ptr; |
| 1517 | btrfs_disk_key_to_cpu(&key, disk_key); |
| 1518 | |
| 1519 | len = sizeof(*disk_key); |
| 1520 | |
| 1521 | if (key.type == BTRFS_CHUNK_ITEM_KEY) { |
| 1522 | chunk = (struct btrfs_chunk *)(ptr + len); |
| 1523 | num_stripes = btrfs_stack_chunk_num_stripes(chunk); |
| 1524 | len += btrfs_chunk_item_size(num_stripes); |
| 1525 | } else { |
| 1526 | ret = -EIO; |
| 1527 | break; |
| 1528 | } |
| 1529 | if (key.objectid == chunk_objectid && |
| 1530 | key.offset == chunk_offset) { |
| 1531 | memmove(ptr, ptr + len, array_size - (cur + len)); |
| 1532 | array_size -= len; |
| 1533 | btrfs_set_super_sys_array_size(super_copy, array_size); |
| 1534 | } else { |
| 1535 | ptr += len; |
| 1536 | cur += len; |
| 1537 | } |
| 1538 | } |
| 1539 | return ret; |
| 1540 | } |
| 1541 | |
| 1542 | static int btrfs_relocate_chunk(struct btrfs_root *root, |
| 1543 | u64 chunk_tree, u64 chunk_objectid, |
| 1544 | u64 chunk_offset) |
| 1545 | { |
| 1546 | struct extent_map_tree *em_tree; |
| 1547 | struct btrfs_root *extent_root; |
| 1548 | struct btrfs_trans_handle *trans; |
| 1549 | struct extent_map *em; |
| 1550 | struct map_lookup *map; |
| 1551 | int ret; |
| 1552 | int i; |
| 1553 | |
| 1554 | printk(KERN_INFO "btrfs relocating chunk %llu\n", |
| 1555 | (unsigned long long)chunk_offset); |
| 1556 | root = root->fs_info->chunk_root; |
| 1557 | extent_root = root->fs_info->extent_root; |
| 1558 | em_tree = &root->fs_info->mapping_tree.map_tree; |
| 1559 | |
| 1560 | /* step one, relocate all the extents inside this chunk */ |
| 1561 | ret = btrfs_relocate_block_group(extent_root, chunk_offset); |
| 1562 | BUG_ON(ret); |
| 1563 | |
| 1564 | trans = btrfs_start_transaction(root, 1); |
| 1565 | BUG_ON(!trans); |
| 1566 | |
| 1567 | lock_chunks(root); |
| 1568 | |
| 1569 | /* |
| 1570 | * step two, delete the device extents and the |
| 1571 | * chunk tree entries |
| 1572 | */ |
| 1573 | spin_lock(&em_tree->lock); |
| 1574 | em = lookup_extent_mapping(em_tree, chunk_offset, 1); |
| 1575 | spin_unlock(&em_tree->lock); |
| 1576 | |
| 1577 | BUG_ON(em->start > chunk_offset || |
| 1578 | em->start + em->len < chunk_offset); |
| 1579 | map = (struct map_lookup *)em->bdev; |
| 1580 | |
| 1581 | for (i = 0; i < map->num_stripes; i++) { |
| 1582 | ret = btrfs_free_dev_extent(trans, map->stripes[i].dev, |
| 1583 | map->stripes[i].physical); |
| 1584 | BUG_ON(ret); |
| 1585 | |
| 1586 | if (map->stripes[i].dev) { |
| 1587 | ret = btrfs_update_device(trans, map->stripes[i].dev); |
| 1588 | BUG_ON(ret); |
| 1589 | } |
| 1590 | } |
| 1591 | ret = btrfs_free_chunk(trans, root, chunk_tree, chunk_objectid, |
| 1592 | chunk_offset); |
| 1593 | |
| 1594 | BUG_ON(ret); |
| 1595 | |
| 1596 | if (map->type & BTRFS_BLOCK_GROUP_SYSTEM) { |
| 1597 | ret = btrfs_del_sys_chunk(root, chunk_objectid, chunk_offset); |
| 1598 | BUG_ON(ret); |
| 1599 | } |
| 1600 | |
| 1601 | ret = btrfs_remove_block_group(trans, extent_root, chunk_offset); |
| 1602 | BUG_ON(ret); |
| 1603 | |
| 1604 | spin_lock(&em_tree->lock); |
| 1605 | remove_extent_mapping(em_tree, em); |
| 1606 | spin_unlock(&em_tree->lock); |
| 1607 | |
| 1608 | kfree(map); |
| 1609 | em->bdev = NULL; |
| 1610 | |
| 1611 | /* once for the tree */ |
| 1612 | free_extent_map(em); |
| 1613 | /* once for us */ |
| 1614 | free_extent_map(em); |
| 1615 | |
| 1616 | unlock_chunks(root); |
| 1617 | btrfs_end_transaction(trans, root); |
| 1618 | return 0; |
| 1619 | } |
| 1620 | |
| 1621 | static int btrfs_relocate_sys_chunks(struct btrfs_root *root) |
| 1622 | { |
| 1623 | struct btrfs_root *chunk_root = root->fs_info->chunk_root; |
| 1624 | struct btrfs_path *path; |
| 1625 | struct extent_buffer *leaf; |
| 1626 | struct btrfs_chunk *chunk; |
| 1627 | struct btrfs_key key; |
| 1628 | struct btrfs_key found_key; |
| 1629 | u64 chunk_tree = chunk_root->root_key.objectid; |
| 1630 | u64 chunk_type; |
| 1631 | int ret; |
| 1632 | |
| 1633 | path = btrfs_alloc_path(); |
| 1634 | if (!path) |
| 1635 | return -ENOMEM; |
| 1636 | |
| 1637 | key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID; |
| 1638 | key.offset = (u64)-1; |
| 1639 | key.type = BTRFS_CHUNK_ITEM_KEY; |
| 1640 | |
| 1641 | while (1) { |
| 1642 | ret = btrfs_search_slot(NULL, chunk_root, &key, path, 0, 0); |
| 1643 | if (ret < 0) |
| 1644 | goto error; |
| 1645 | BUG_ON(ret == 0); |
| 1646 | |
| 1647 | ret = btrfs_previous_item(chunk_root, path, key.objectid, |
| 1648 | key.type); |
| 1649 | if (ret < 0) |
| 1650 | goto error; |
| 1651 | if (ret > 0) |
| 1652 | break; |
| 1653 | |
| 1654 | leaf = path->nodes[0]; |
| 1655 | btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); |
| 1656 | |
| 1657 | chunk = btrfs_item_ptr(leaf, path->slots[0], |
| 1658 | struct btrfs_chunk); |
| 1659 | chunk_type = btrfs_chunk_type(leaf, chunk); |
| 1660 | btrfs_release_path(chunk_root, path); |
| 1661 | |
| 1662 | if (chunk_type & BTRFS_BLOCK_GROUP_SYSTEM) { |
| 1663 | ret = btrfs_relocate_chunk(chunk_root, chunk_tree, |
| 1664 | found_key.objectid, |
| 1665 | found_key.offset); |
| 1666 | BUG_ON(ret); |
| 1667 | } |
| 1668 | |
| 1669 | if (found_key.offset == 0) |
| 1670 | break; |
| 1671 | key.offset = found_key.offset - 1; |
| 1672 | } |
| 1673 | ret = 0; |
| 1674 | error: |
| 1675 | btrfs_free_path(path); |
| 1676 | return ret; |
| 1677 | } |
| 1678 | |
| 1679 | static u64 div_factor(u64 num, int factor) |
| 1680 | { |
| 1681 | if (factor == 10) |
| 1682 | return num; |
| 1683 | num *= factor; |
| 1684 | do_div(num, 10); |
| 1685 | return num; |
| 1686 | } |
| 1687 | |
| 1688 | int btrfs_balance(struct btrfs_root *dev_root) |
| 1689 | { |
| 1690 | int ret; |
| 1691 | struct list_head *devices = &dev_root->fs_info->fs_devices->devices; |
| 1692 | struct btrfs_device *device; |
| 1693 | u64 old_size; |
| 1694 | u64 size_to_free; |
| 1695 | struct btrfs_path *path; |
| 1696 | struct btrfs_key key; |
| 1697 | struct btrfs_chunk *chunk; |
| 1698 | struct btrfs_root *chunk_root = dev_root->fs_info->chunk_root; |
| 1699 | struct btrfs_trans_handle *trans; |
| 1700 | struct btrfs_key found_key; |
| 1701 | |
| 1702 | if (dev_root->fs_info->sb->s_flags & MS_RDONLY) |
| 1703 | return -EROFS; |
| 1704 | |
| 1705 | mutex_lock(&dev_root->fs_info->volume_mutex); |
| 1706 | dev_root = dev_root->fs_info->dev_root; |
| 1707 | |
| 1708 | /* step one make some room on all the devices */ |
| 1709 | list_for_each_entry(device, devices, dev_list) { |
| 1710 | old_size = device->total_bytes; |
| 1711 | size_to_free = div_factor(old_size, 1); |
| 1712 | size_to_free = min(size_to_free, (u64)1 * 1024 * 1024); |
| 1713 | if (!device->writeable || |
| 1714 | device->total_bytes - device->bytes_used > size_to_free) |
| 1715 | continue; |
| 1716 | |
| 1717 | ret = btrfs_shrink_device(device, old_size - size_to_free); |
| 1718 | BUG_ON(ret); |
| 1719 | |
| 1720 | trans = btrfs_start_transaction(dev_root, 1); |
| 1721 | BUG_ON(!trans); |
| 1722 | |
| 1723 | ret = btrfs_grow_device(trans, device, old_size); |
| 1724 | BUG_ON(ret); |
| 1725 | |
| 1726 | btrfs_end_transaction(trans, dev_root); |
| 1727 | } |
| 1728 | |
| 1729 | /* step two, relocate all the chunks */ |
| 1730 | path = btrfs_alloc_path(); |
| 1731 | BUG_ON(!path); |
| 1732 | |
| 1733 | key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID; |
| 1734 | key.offset = (u64)-1; |
| 1735 | key.type = BTRFS_CHUNK_ITEM_KEY; |
| 1736 | |
| 1737 | while (1) { |
| 1738 | ret = btrfs_search_slot(NULL, chunk_root, &key, path, 0, 0); |
| 1739 | if (ret < 0) |
| 1740 | goto error; |
| 1741 | |
| 1742 | /* |
| 1743 | * this shouldn't happen, it means the last relocate |
| 1744 | * failed |
| 1745 | */ |
| 1746 | if (ret == 0) |
| 1747 | break; |
| 1748 | |
| 1749 | ret = btrfs_previous_item(chunk_root, path, 0, |
| 1750 | BTRFS_CHUNK_ITEM_KEY); |
| 1751 | if (ret) |
| 1752 | break; |
| 1753 | |
| 1754 | btrfs_item_key_to_cpu(path->nodes[0], &found_key, |
| 1755 | path->slots[0]); |
| 1756 | if (found_key.objectid != key.objectid) |
| 1757 | break; |
| 1758 | |
| 1759 | chunk = btrfs_item_ptr(path->nodes[0], |
| 1760 | path->slots[0], |
| 1761 | struct btrfs_chunk); |
| 1762 | key.offset = found_key.offset; |
| 1763 | /* chunk zero is special */ |
| 1764 | if (key.offset == 0) |
| 1765 | break; |
| 1766 | |
| 1767 | btrfs_release_path(chunk_root, path); |
| 1768 | ret = btrfs_relocate_chunk(chunk_root, |
| 1769 | chunk_root->root_key.objectid, |
| 1770 | found_key.objectid, |
| 1771 | found_key.offset); |
| 1772 | BUG_ON(ret); |
| 1773 | } |
| 1774 | ret = 0; |
| 1775 | error: |
| 1776 | btrfs_free_path(path); |
| 1777 | mutex_unlock(&dev_root->fs_info->volume_mutex); |
| 1778 | return ret; |
| 1779 | } |
| 1780 | |
| 1781 | /* |
| 1782 | * shrinking a device means finding all of the device extents past |
| 1783 | * the new size, and then following the back refs to the chunks. |
| 1784 | * The chunk relocation code actually frees the device extent |
| 1785 | */ |
| 1786 | int btrfs_shrink_device(struct btrfs_device *device, u64 new_size) |
| 1787 | { |
| 1788 | struct btrfs_trans_handle *trans; |
| 1789 | struct btrfs_root *root = device->dev_root; |
| 1790 | struct btrfs_dev_extent *dev_extent = NULL; |
| 1791 | struct btrfs_path *path; |
| 1792 | u64 length; |
| 1793 | u64 chunk_tree; |
| 1794 | u64 chunk_objectid; |
| 1795 | u64 chunk_offset; |
| 1796 | int ret; |
| 1797 | int slot; |
| 1798 | struct extent_buffer *l; |
| 1799 | struct btrfs_key key; |
| 1800 | struct btrfs_super_block *super_copy = &root->fs_info->super_copy; |
| 1801 | u64 old_total = btrfs_super_total_bytes(super_copy); |
| 1802 | u64 diff = device->total_bytes - new_size; |
| 1803 | |
| 1804 | if (new_size >= device->total_bytes) |
| 1805 | return -EINVAL; |
| 1806 | |
| 1807 | path = btrfs_alloc_path(); |
| 1808 | if (!path) |
| 1809 | return -ENOMEM; |
| 1810 | |
| 1811 | trans = btrfs_start_transaction(root, 1); |
| 1812 | if (!trans) { |
| 1813 | ret = -ENOMEM; |
| 1814 | goto done; |
| 1815 | } |
| 1816 | |
| 1817 | path->reada = 2; |
| 1818 | |
| 1819 | lock_chunks(root); |
| 1820 | |
| 1821 | device->total_bytes = new_size; |
| 1822 | if (device->writeable) |
| 1823 | device->fs_devices->total_rw_bytes -= diff; |
| 1824 | ret = btrfs_update_device(trans, device); |
| 1825 | if (ret) { |
| 1826 | unlock_chunks(root); |
| 1827 | btrfs_end_transaction(trans, root); |
| 1828 | goto done; |
| 1829 | } |
| 1830 | WARN_ON(diff > old_total); |
| 1831 | btrfs_set_super_total_bytes(super_copy, old_total - diff); |
| 1832 | unlock_chunks(root); |
| 1833 | btrfs_end_transaction(trans, root); |
| 1834 | |
| 1835 | key.objectid = device->devid; |
| 1836 | key.offset = (u64)-1; |
| 1837 | key.type = BTRFS_DEV_EXTENT_KEY; |
| 1838 | |
| 1839 | while (1) { |
| 1840 | ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); |
| 1841 | if (ret < 0) |
| 1842 | goto done; |
| 1843 | |
| 1844 | ret = btrfs_previous_item(root, path, 0, key.type); |
| 1845 | if (ret < 0) |
| 1846 | goto done; |
| 1847 | if (ret) { |
| 1848 | ret = 0; |
| 1849 | goto done; |
| 1850 | } |
| 1851 | |
| 1852 | l = path->nodes[0]; |
| 1853 | slot = path->slots[0]; |
| 1854 | btrfs_item_key_to_cpu(l, &key, path->slots[0]); |
| 1855 | |
| 1856 | if (key.objectid != device->devid) |
| 1857 | goto done; |
| 1858 | |
| 1859 | dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent); |
| 1860 | length = btrfs_dev_extent_length(l, dev_extent); |
| 1861 | |
| 1862 | if (key.offset + length <= new_size) |
| 1863 | goto done; |
| 1864 | |
| 1865 | chunk_tree = btrfs_dev_extent_chunk_tree(l, dev_extent); |
| 1866 | chunk_objectid = btrfs_dev_extent_chunk_objectid(l, dev_extent); |
| 1867 | chunk_offset = btrfs_dev_extent_chunk_offset(l, dev_extent); |
| 1868 | btrfs_release_path(root, path); |
| 1869 | |
| 1870 | ret = btrfs_relocate_chunk(root, chunk_tree, chunk_objectid, |
| 1871 | chunk_offset); |
| 1872 | if (ret) |
| 1873 | goto done; |
| 1874 | } |
| 1875 | |
| 1876 | done: |
| 1877 | btrfs_free_path(path); |
| 1878 | return ret; |
| 1879 | } |
| 1880 | |
| 1881 | static int btrfs_add_system_chunk(struct btrfs_trans_handle *trans, |
| 1882 | struct btrfs_root *root, |
| 1883 | struct btrfs_key *key, |
| 1884 | struct btrfs_chunk *chunk, int item_size) |
| 1885 | { |
| 1886 | struct btrfs_super_block *super_copy = &root->fs_info->super_copy; |
| 1887 | struct btrfs_disk_key disk_key; |
| 1888 | u32 array_size; |
| 1889 | u8 *ptr; |
| 1890 | |
| 1891 | array_size = btrfs_super_sys_array_size(super_copy); |
| 1892 | if (array_size + item_size > BTRFS_SYSTEM_CHUNK_ARRAY_SIZE) |
| 1893 | return -EFBIG; |
| 1894 | |
| 1895 | ptr = super_copy->sys_chunk_array + array_size; |
| 1896 | btrfs_cpu_key_to_disk(&disk_key, key); |
| 1897 | memcpy(ptr, &disk_key, sizeof(disk_key)); |
| 1898 | ptr += sizeof(disk_key); |
| 1899 | memcpy(ptr, chunk, item_size); |
| 1900 | item_size += sizeof(disk_key); |
| 1901 | btrfs_set_super_sys_array_size(super_copy, array_size + item_size); |
| 1902 | return 0; |
| 1903 | } |
| 1904 | |
| 1905 | static noinline u64 chunk_bytes_by_type(u64 type, u64 calc_size, |
| 1906 | int num_stripes, int sub_stripes) |
| 1907 | { |
| 1908 | if (type & (BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_DUP)) |
| 1909 | return calc_size; |
| 1910 | else if (type & BTRFS_BLOCK_GROUP_RAID10) |
| 1911 | return calc_size * (num_stripes / sub_stripes); |
| 1912 | else |
| 1913 | return calc_size * num_stripes; |
| 1914 | } |
| 1915 | |
| 1916 | static int __btrfs_alloc_chunk(struct btrfs_trans_handle *trans, |
| 1917 | struct btrfs_root *extent_root, |
| 1918 | struct map_lookup **map_ret, |
| 1919 | u64 *num_bytes, u64 *stripe_size, |
| 1920 | u64 start, u64 type) |
| 1921 | { |
| 1922 | struct btrfs_fs_info *info = extent_root->fs_info; |
| 1923 | struct btrfs_device *device = NULL; |
| 1924 | struct btrfs_fs_devices *fs_devices = info->fs_devices; |
| 1925 | struct list_head *cur; |
| 1926 | struct map_lookup *map = NULL; |
| 1927 | struct extent_map_tree *em_tree; |
| 1928 | struct extent_map *em; |
| 1929 | struct list_head private_devs; |
| 1930 | int min_stripe_size = 1 * 1024 * 1024; |
| 1931 | u64 calc_size = 1024 * 1024 * 1024; |
| 1932 | u64 max_chunk_size = calc_size; |
| 1933 | u64 min_free; |
| 1934 | u64 avail; |
| 1935 | u64 max_avail = 0; |
| 1936 | u64 dev_offset; |
| 1937 | int num_stripes = 1; |
| 1938 | int min_stripes = 1; |
| 1939 | int sub_stripes = 0; |
| 1940 | int looped = 0; |
| 1941 | int ret; |
| 1942 | int index; |
| 1943 | int stripe_len = 64 * 1024; |
| 1944 | |
| 1945 | if ((type & BTRFS_BLOCK_GROUP_RAID1) && |
| 1946 | (type & BTRFS_BLOCK_GROUP_DUP)) { |
| 1947 | WARN_ON(1); |
| 1948 | type &= ~BTRFS_BLOCK_GROUP_DUP; |
| 1949 | } |
| 1950 | if (list_empty(&fs_devices->alloc_list)) |
| 1951 | return -ENOSPC; |
| 1952 | |
| 1953 | if (type & (BTRFS_BLOCK_GROUP_RAID0)) { |
| 1954 | num_stripes = fs_devices->rw_devices; |
| 1955 | min_stripes = 2; |
| 1956 | } |
| 1957 | if (type & (BTRFS_BLOCK_GROUP_DUP)) { |
| 1958 | num_stripes = 2; |
| 1959 | min_stripes = 2; |
| 1960 | } |
| 1961 | if (type & (BTRFS_BLOCK_GROUP_RAID1)) { |
| 1962 | num_stripes = min_t(u64, 2, fs_devices->rw_devices); |
| 1963 | if (num_stripes < 2) |
| 1964 | return -ENOSPC; |
| 1965 | min_stripes = 2; |
| 1966 | } |
| 1967 | if (type & (BTRFS_BLOCK_GROUP_RAID10)) { |
| 1968 | num_stripes = fs_devices->rw_devices; |
| 1969 | if (num_stripes < 4) |
| 1970 | return -ENOSPC; |
| 1971 | num_stripes &= ~(u32)1; |
| 1972 | sub_stripes = 2; |
| 1973 | min_stripes = 4; |
| 1974 | } |
| 1975 | |
| 1976 | if (type & BTRFS_BLOCK_GROUP_DATA) { |
| 1977 | max_chunk_size = 10 * calc_size; |
| 1978 | min_stripe_size = 64 * 1024 * 1024; |
| 1979 | } else if (type & BTRFS_BLOCK_GROUP_METADATA) { |
| 1980 | max_chunk_size = 4 * calc_size; |
| 1981 | min_stripe_size = 32 * 1024 * 1024; |
| 1982 | } else if (type & BTRFS_BLOCK_GROUP_SYSTEM) { |
| 1983 | calc_size = 8 * 1024 * 1024; |
| 1984 | max_chunk_size = calc_size * 2; |
| 1985 | min_stripe_size = 1 * 1024 * 1024; |
| 1986 | } |
| 1987 | |
| 1988 | /* we don't want a chunk larger than 10% of writeable space */ |
| 1989 | max_chunk_size = min(div_factor(fs_devices->total_rw_bytes, 1), |
| 1990 | max_chunk_size); |
| 1991 | |
| 1992 | again: |
| 1993 | if (!map || map->num_stripes != num_stripes) { |
| 1994 | kfree(map); |
| 1995 | map = kmalloc(map_lookup_size(num_stripes), GFP_NOFS); |
| 1996 | if (!map) |
| 1997 | return -ENOMEM; |
| 1998 | map->num_stripes = num_stripes; |
| 1999 | } |
| 2000 | |
| 2001 | if (calc_size * num_stripes > max_chunk_size) { |
| 2002 | calc_size = max_chunk_size; |
| 2003 | do_div(calc_size, num_stripes); |
| 2004 | do_div(calc_size, stripe_len); |
| 2005 | calc_size *= stripe_len; |
| 2006 | } |
| 2007 | /* we don't want tiny stripes */ |
| 2008 | calc_size = max_t(u64, min_stripe_size, calc_size); |
| 2009 | |
| 2010 | do_div(calc_size, stripe_len); |
| 2011 | calc_size *= stripe_len; |
| 2012 | |
| 2013 | cur = fs_devices->alloc_list.next; |
| 2014 | index = 0; |
| 2015 | |
| 2016 | if (type & BTRFS_BLOCK_GROUP_DUP) |
| 2017 | min_free = calc_size * 2; |
| 2018 | else |
| 2019 | min_free = calc_size; |
| 2020 | |
| 2021 | /* |
| 2022 | * we add 1MB because we never use the first 1MB of the device, unless |
| 2023 | * we've looped, then we are likely allocating the maximum amount of |
| 2024 | * space left already |
| 2025 | */ |
| 2026 | if (!looped) |
| 2027 | min_free += 1024 * 1024; |
| 2028 | |
| 2029 | INIT_LIST_HEAD(&private_devs); |
| 2030 | while (index < num_stripes) { |
| 2031 | device = list_entry(cur, struct btrfs_device, dev_alloc_list); |
| 2032 | BUG_ON(!device->writeable); |
| 2033 | if (device->total_bytes > device->bytes_used) |
| 2034 | avail = device->total_bytes - device->bytes_used; |
| 2035 | else |
| 2036 | avail = 0; |
| 2037 | cur = cur->next; |
| 2038 | |
| 2039 | if (device->in_fs_metadata && avail >= min_free) { |
| 2040 | ret = find_free_dev_extent(trans, device, |
| 2041 | min_free, &dev_offset); |
| 2042 | if (ret == 0) { |
| 2043 | list_move_tail(&device->dev_alloc_list, |
| 2044 | &private_devs); |
| 2045 | map->stripes[index].dev = device; |
| 2046 | map->stripes[index].physical = dev_offset; |
| 2047 | index++; |
| 2048 | if (type & BTRFS_BLOCK_GROUP_DUP) { |
| 2049 | map->stripes[index].dev = device; |
| 2050 | map->stripes[index].physical = |
| 2051 | dev_offset + calc_size; |
| 2052 | index++; |
| 2053 | } |
| 2054 | } |
| 2055 | } else if (device->in_fs_metadata && avail > max_avail) |
| 2056 | max_avail = avail; |
| 2057 | if (cur == &fs_devices->alloc_list) |
| 2058 | break; |
| 2059 | } |
| 2060 | list_splice(&private_devs, &fs_devices->alloc_list); |
| 2061 | if (index < num_stripes) { |
| 2062 | if (index >= min_stripes) { |
| 2063 | num_stripes = index; |
| 2064 | if (type & (BTRFS_BLOCK_GROUP_RAID10)) { |
| 2065 | num_stripes /= sub_stripes; |
| 2066 | num_stripes *= sub_stripes; |
| 2067 | } |
| 2068 | looped = 1; |
| 2069 | goto again; |
| 2070 | } |
| 2071 | if (!looped && max_avail > 0) { |
| 2072 | looped = 1; |
| 2073 | calc_size = max_avail; |
| 2074 | goto again; |
| 2075 | } |
| 2076 | kfree(map); |
| 2077 | return -ENOSPC; |
| 2078 | } |
| 2079 | map->sector_size = extent_root->sectorsize; |
| 2080 | map->stripe_len = stripe_len; |
| 2081 | map->io_align = stripe_len; |
| 2082 | map->io_width = stripe_len; |
| 2083 | map->type = type; |
| 2084 | map->num_stripes = num_stripes; |
| 2085 | map->sub_stripes = sub_stripes; |
| 2086 | |
| 2087 | *map_ret = map; |
| 2088 | *stripe_size = calc_size; |
| 2089 | *num_bytes = chunk_bytes_by_type(type, calc_size, |
| 2090 | num_stripes, sub_stripes); |
| 2091 | |
| 2092 | em = alloc_extent_map(GFP_NOFS); |
| 2093 | if (!em) { |
| 2094 | kfree(map); |
| 2095 | return -ENOMEM; |
| 2096 | } |
| 2097 | em->bdev = (struct block_device *)map; |
| 2098 | em->start = start; |
| 2099 | em->len = *num_bytes; |
| 2100 | em->block_start = 0; |
| 2101 | em->block_len = em->len; |
| 2102 | |
| 2103 | em_tree = &extent_root->fs_info->mapping_tree.map_tree; |
| 2104 | spin_lock(&em_tree->lock); |
| 2105 | ret = add_extent_mapping(em_tree, em); |
| 2106 | spin_unlock(&em_tree->lock); |
| 2107 | BUG_ON(ret); |
| 2108 | free_extent_map(em); |
| 2109 | |
| 2110 | ret = btrfs_make_block_group(trans, extent_root, 0, type, |
| 2111 | BTRFS_FIRST_CHUNK_TREE_OBJECTID, |
| 2112 | start, *num_bytes); |
| 2113 | BUG_ON(ret); |
| 2114 | |
| 2115 | index = 0; |
| 2116 | while (index < map->num_stripes) { |
| 2117 | device = map->stripes[index].dev; |
| 2118 | dev_offset = map->stripes[index].physical; |
| 2119 | |
| 2120 | ret = btrfs_alloc_dev_extent(trans, device, |
| 2121 | info->chunk_root->root_key.objectid, |
| 2122 | BTRFS_FIRST_CHUNK_TREE_OBJECTID, |
| 2123 | start, dev_offset, calc_size); |
| 2124 | BUG_ON(ret); |
| 2125 | index++; |
| 2126 | } |
| 2127 | |
| 2128 | return 0; |
| 2129 | } |
| 2130 | |
| 2131 | static int __finish_chunk_alloc(struct btrfs_trans_handle *trans, |
| 2132 | struct btrfs_root *extent_root, |
| 2133 | struct map_lookup *map, u64 chunk_offset, |
| 2134 | u64 chunk_size, u64 stripe_size) |
| 2135 | { |
| 2136 | u64 dev_offset; |
| 2137 | struct btrfs_key key; |
| 2138 | struct btrfs_root *chunk_root = extent_root->fs_info->chunk_root; |
| 2139 | struct btrfs_device *device; |
| 2140 | struct btrfs_chunk *chunk; |
| 2141 | struct btrfs_stripe *stripe; |
| 2142 | size_t item_size = btrfs_chunk_item_size(map->num_stripes); |
| 2143 | int index = 0; |
| 2144 | int ret; |
| 2145 | |
| 2146 | chunk = kzalloc(item_size, GFP_NOFS); |
| 2147 | if (!chunk) |
| 2148 | return -ENOMEM; |
| 2149 | |
| 2150 | index = 0; |
| 2151 | while (index < map->num_stripes) { |
| 2152 | device = map->stripes[index].dev; |
| 2153 | device->bytes_used += stripe_size; |
| 2154 | ret = btrfs_update_device(trans, device); |
| 2155 | BUG_ON(ret); |
| 2156 | index++; |
| 2157 | } |
| 2158 | |
| 2159 | index = 0; |
| 2160 | stripe = &chunk->stripe; |
| 2161 | while (index < map->num_stripes) { |
| 2162 | device = map->stripes[index].dev; |
| 2163 | dev_offset = map->stripes[index].physical; |
| 2164 | |
| 2165 | btrfs_set_stack_stripe_devid(stripe, device->devid); |
| 2166 | btrfs_set_stack_stripe_offset(stripe, dev_offset); |
| 2167 | memcpy(stripe->dev_uuid, device->uuid, BTRFS_UUID_SIZE); |
| 2168 | stripe++; |
| 2169 | index++; |
| 2170 | } |
| 2171 | |
| 2172 | btrfs_set_stack_chunk_length(chunk, chunk_size); |
| 2173 | btrfs_set_stack_chunk_owner(chunk, extent_root->root_key.objectid); |
| 2174 | btrfs_set_stack_chunk_stripe_len(chunk, map->stripe_len); |
| 2175 | btrfs_set_stack_chunk_type(chunk, map->type); |
| 2176 | btrfs_set_stack_chunk_num_stripes(chunk, map->num_stripes); |
| 2177 | btrfs_set_stack_chunk_io_align(chunk, map->stripe_len); |
| 2178 | btrfs_set_stack_chunk_io_width(chunk, map->stripe_len); |
| 2179 | btrfs_set_stack_chunk_sector_size(chunk, extent_root->sectorsize); |
| 2180 | btrfs_set_stack_chunk_sub_stripes(chunk, map->sub_stripes); |
| 2181 | |
| 2182 | key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID; |
| 2183 | key.type = BTRFS_CHUNK_ITEM_KEY; |
| 2184 | key.offset = chunk_offset; |
| 2185 | |
| 2186 | ret = btrfs_insert_item(trans, chunk_root, &key, chunk, item_size); |
| 2187 | BUG_ON(ret); |
| 2188 | |
| 2189 | if (map->type & BTRFS_BLOCK_GROUP_SYSTEM) { |
| 2190 | ret = btrfs_add_system_chunk(trans, chunk_root, &key, chunk, |
| 2191 | item_size); |
| 2192 | BUG_ON(ret); |
| 2193 | } |
| 2194 | kfree(chunk); |
| 2195 | return 0; |
| 2196 | } |
| 2197 | |
| 2198 | /* |
| 2199 | * Chunk allocation falls into two parts. The first part does works |
| 2200 | * that make the new allocated chunk useable, but not do any operation |
| 2201 | * that modifies the chunk tree. The second part does the works that |
| 2202 | * require modifying the chunk tree. This division is important for the |
| 2203 | * bootstrap process of adding storage to a seed btrfs. |
| 2204 | */ |
| 2205 | int btrfs_alloc_chunk(struct btrfs_trans_handle *trans, |
| 2206 | struct btrfs_root *extent_root, u64 type) |
| 2207 | { |
| 2208 | u64 chunk_offset; |
| 2209 | u64 chunk_size; |
| 2210 | u64 stripe_size; |
| 2211 | struct map_lookup *map; |
| 2212 | struct btrfs_root *chunk_root = extent_root->fs_info->chunk_root; |
| 2213 | int ret; |
| 2214 | |
| 2215 | ret = find_next_chunk(chunk_root, BTRFS_FIRST_CHUNK_TREE_OBJECTID, |
| 2216 | &chunk_offset); |
| 2217 | if (ret) |
| 2218 | return ret; |
| 2219 | |
| 2220 | ret = __btrfs_alloc_chunk(trans, extent_root, &map, &chunk_size, |
| 2221 | &stripe_size, chunk_offset, type); |
| 2222 | if (ret) |
| 2223 | return ret; |
| 2224 | |
| 2225 | ret = __finish_chunk_alloc(trans, extent_root, map, chunk_offset, |
| 2226 | chunk_size, stripe_size); |
| 2227 | BUG_ON(ret); |
| 2228 | return 0; |
| 2229 | } |
| 2230 | |
| 2231 | static noinline int init_first_rw_device(struct btrfs_trans_handle *trans, |
| 2232 | struct btrfs_root *root, |
| 2233 | struct btrfs_device *device) |
| 2234 | { |
| 2235 | u64 chunk_offset; |
| 2236 | u64 sys_chunk_offset; |
| 2237 | u64 chunk_size; |
| 2238 | u64 sys_chunk_size; |
| 2239 | u64 stripe_size; |
| 2240 | u64 sys_stripe_size; |
| 2241 | u64 alloc_profile; |
| 2242 | struct map_lookup *map; |
| 2243 | struct map_lookup *sys_map; |
| 2244 | struct btrfs_fs_info *fs_info = root->fs_info; |
| 2245 | struct btrfs_root *extent_root = fs_info->extent_root; |
| 2246 | int ret; |
| 2247 | |
| 2248 | ret = find_next_chunk(fs_info->chunk_root, |
| 2249 | BTRFS_FIRST_CHUNK_TREE_OBJECTID, &chunk_offset); |
| 2250 | BUG_ON(ret); |
| 2251 | |
| 2252 | alloc_profile = BTRFS_BLOCK_GROUP_METADATA | |
| 2253 | (fs_info->metadata_alloc_profile & |
| 2254 | fs_info->avail_metadata_alloc_bits); |
| 2255 | alloc_profile = btrfs_reduce_alloc_profile(root, alloc_profile); |
| 2256 | |
| 2257 | ret = __btrfs_alloc_chunk(trans, extent_root, &map, &chunk_size, |
| 2258 | &stripe_size, chunk_offset, alloc_profile); |
| 2259 | BUG_ON(ret); |
| 2260 | |
| 2261 | sys_chunk_offset = chunk_offset + chunk_size; |
| 2262 | |
| 2263 | alloc_profile = BTRFS_BLOCK_GROUP_SYSTEM | |
| 2264 | (fs_info->system_alloc_profile & |
| 2265 | fs_info->avail_system_alloc_bits); |
| 2266 | alloc_profile = btrfs_reduce_alloc_profile(root, alloc_profile); |
| 2267 | |
| 2268 | ret = __btrfs_alloc_chunk(trans, extent_root, &sys_map, |
| 2269 | &sys_chunk_size, &sys_stripe_size, |
| 2270 | sys_chunk_offset, alloc_profile); |
| 2271 | BUG_ON(ret); |
| 2272 | |
| 2273 | ret = btrfs_add_device(trans, fs_info->chunk_root, device); |
| 2274 | BUG_ON(ret); |
| 2275 | |
| 2276 | /* |
| 2277 | * Modifying chunk tree needs allocating new blocks from both |
| 2278 | * system block group and metadata block group. So we only can |
| 2279 | * do operations require modifying the chunk tree after both |
| 2280 | * block groups were created. |
| 2281 | */ |
| 2282 | ret = __finish_chunk_alloc(trans, extent_root, map, chunk_offset, |
| 2283 | chunk_size, stripe_size); |
| 2284 | BUG_ON(ret); |
| 2285 | |
| 2286 | ret = __finish_chunk_alloc(trans, extent_root, sys_map, |
| 2287 | sys_chunk_offset, sys_chunk_size, |
| 2288 | sys_stripe_size); |
| 2289 | BUG_ON(ret); |
| 2290 | return 0; |
| 2291 | } |
| 2292 | |
| 2293 | int btrfs_chunk_readonly(struct btrfs_root *root, u64 chunk_offset) |
| 2294 | { |
| 2295 | struct extent_map *em; |
| 2296 | struct map_lookup *map; |
| 2297 | struct btrfs_mapping_tree *map_tree = &root->fs_info->mapping_tree; |
| 2298 | int readonly = 0; |
| 2299 | int i; |
| 2300 | |
| 2301 | spin_lock(&map_tree->map_tree.lock); |
| 2302 | em = lookup_extent_mapping(&map_tree->map_tree, chunk_offset, 1); |
| 2303 | spin_unlock(&map_tree->map_tree.lock); |
| 2304 | if (!em) |
| 2305 | return 1; |
| 2306 | |
| 2307 | map = (struct map_lookup *)em->bdev; |
| 2308 | for (i = 0; i < map->num_stripes; i++) { |
| 2309 | if (!map->stripes[i].dev->writeable) { |
| 2310 | readonly = 1; |
| 2311 | break; |
| 2312 | } |
| 2313 | } |
| 2314 | free_extent_map(em); |
| 2315 | return readonly; |
| 2316 | } |
| 2317 | |
| 2318 | void btrfs_mapping_init(struct btrfs_mapping_tree *tree) |
| 2319 | { |
| 2320 | extent_map_tree_init(&tree->map_tree, GFP_NOFS); |
| 2321 | } |
| 2322 | |
| 2323 | void btrfs_mapping_tree_free(struct btrfs_mapping_tree *tree) |
| 2324 | { |
| 2325 | struct extent_map *em; |
| 2326 | |
| 2327 | while (1) { |
| 2328 | spin_lock(&tree->map_tree.lock); |
| 2329 | em = lookup_extent_mapping(&tree->map_tree, 0, (u64)-1); |
| 2330 | if (em) |
| 2331 | remove_extent_mapping(&tree->map_tree, em); |
| 2332 | spin_unlock(&tree->map_tree.lock); |
| 2333 | if (!em) |
| 2334 | break; |
| 2335 | kfree(em->bdev); |
| 2336 | /* once for us */ |
| 2337 | free_extent_map(em); |
| 2338 | /* once for the tree */ |
| 2339 | free_extent_map(em); |
| 2340 | } |
| 2341 | } |
| 2342 | |
| 2343 | int btrfs_num_copies(struct btrfs_mapping_tree *map_tree, u64 logical, u64 len) |
| 2344 | { |
| 2345 | struct extent_map *em; |
| 2346 | struct map_lookup *map; |
| 2347 | struct extent_map_tree *em_tree = &map_tree->map_tree; |
| 2348 | int ret; |
| 2349 | |
| 2350 | spin_lock(&em_tree->lock); |
| 2351 | em = lookup_extent_mapping(em_tree, logical, len); |
| 2352 | spin_unlock(&em_tree->lock); |
| 2353 | BUG_ON(!em); |
| 2354 | |
| 2355 | BUG_ON(em->start > logical || em->start + em->len < logical); |
| 2356 | map = (struct map_lookup *)em->bdev; |
| 2357 | if (map->type & (BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID1)) |
| 2358 | ret = map->num_stripes; |
| 2359 | else if (map->type & BTRFS_BLOCK_GROUP_RAID10) |
| 2360 | ret = map->sub_stripes; |
| 2361 | else |
| 2362 | ret = 1; |
| 2363 | free_extent_map(em); |
| 2364 | return ret; |
| 2365 | } |
| 2366 | |
| 2367 | static int find_live_mirror(struct map_lookup *map, int first, int num, |
| 2368 | int optimal) |
| 2369 | { |
| 2370 | int i; |
| 2371 | if (map->stripes[optimal].dev->bdev) |
| 2372 | return optimal; |
| 2373 | for (i = first; i < first + num; i++) { |
| 2374 | if (map->stripes[i].dev->bdev) |
| 2375 | return i; |
| 2376 | } |
| 2377 | /* we couldn't find one that doesn't fail. Just return something |
| 2378 | * and the io error handling code will clean up eventually |
| 2379 | */ |
| 2380 | return optimal; |
| 2381 | } |
| 2382 | |
| 2383 | static int __btrfs_map_block(struct btrfs_mapping_tree *map_tree, int rw, |
| 2384 | u64 logical, u64 *length, |
| 2385 | struct btrfs_multi_bio **multi_ret, |
| 2386 | int mirror_num, struct page *unplug_page) |
| 2387 | { |
| 2388 | struct extent_map *em; |
| 2389 | struct map_lookup *map; |
| 2390 | struct extent_map_tree *em_tree = &map_tree->map_tree; |
| 2391 | u64 offset; |
| 2392 | u64 stripe_offset; |
| 2393 | u64 stripe_nr; |
| 2394 | int stripes_allocated = 8; |
| 2395 | int stripes_required = 1; |
| 2396 | int stripe_index; |
| 2397 | int i; |
| 2398 | int num_stripes; |
| 2399 | int max_errors = 0; |
| 2400 | struct btrfs_multi_bio *multi = NULL; |
| 2401 | |
| 2402 | if (multi_ret && !(rw & (1 << BIO_RW))) |
| 2403 | stripes_allocated = 1; |
| 2404 | again: |
| 2405 | if (multi_ret) { |
| 2406 | multi = kzalloc(btrfs_multi_bio_size(stripes_allocated), |
| 2407 | GFP_NOFS); |
| 2408 | if (!multi) |
| 2409 | return -ENOMEM; |
| 2410 | |
| 2411 | atomic_set(&multi->error, 0); |
| 2412 | } |
| 2413 | |
| 2414 | spin_lock(&em_tree->lock); |
| 2415 | em = lookup_extent_mapping(em_tree, logical, *length); |
| 2416 | spin_unlock(&em_tree->lock); |
| 2417 | |
| 2418 | if (!em && unplug_page) |
| 2419 | return 0; |
| 2420 | |
| 2421 | if (!em) { |
| 2422 | printk(KERN_CRIT "unable to find logical %llu len %llu\n", |
| 2423 | (unsigned long long)logical, |
| 2424 | (unsigned long long)*length); |
| 2425 | BUG(); |
| 2426 | } |
| 2427 | |
| 2428 | BUG_ON(em->start > logical || em->start + em->len < logical); |
| 2429 | map = (struct map_lookup *)em->bdev; |
| 2430 | offset = logical - em->start; |
| 2431 | |
| 2432 | if (mirror_num > map->num_stripes) |
| 2433 | mirror_num = 0; |
| 2434 | |
| 2435 | /* if our multi bio struct is too small, back off and try again */ |
| 2436 | if (rw & (1 << BIO_RW)) { |
| 2437 | if (map->type & (BTRFS_BLOCK_GROUP_RAID1 | |
| 2438 | BTRFS_BLOCK_GROUP_DUP)) { |
| 2439 | stripes_required = map->num_stripes; |
| 2440 | max_errors = 1; |
| 2441 | } else if (map->type & BTRFS_BLOCK_GROUP_RAID10) { |
| 2442 | stripes_required = map->sub_stripes; |
| 2443 | max_errors = 1; |
| 2444 | } |
| 2445 | } |
| 2446 | if (multi_ret && rw == WRITE && |
| 2447 | stripes_allocated < stripes_required) { |
| 2448 | stripes_allocated = map->num_stripes; |
| 2449 | free_extent_map(em); |
| 2450 | kfree(multi); |
| 2451 | goto again; |
| 2452 | } |
| 2453 | stripe_nr = offset; |
| 2454 | /* |
| 2455 | * stripe_nr counts the total number of stripes we have to stride |
| 2456 | * to get to this block |
| 2457 | */ |
| 2458 | do_div(stripe_nr, map->stripe_len); |
| 2459 | |
| 2460 | stripe_offset = stripe_nr * map->stripe_len; |
| 2461 | BUG_ON(offset < stripe_offset); |
| 2462 | |
| 2463 | /* stripe_offset is the offset of this block in its stripe*/ |
| 2464 | stripe_offset = offset - stripe_offset; |
| 2465 | |
| 2466 | if (map->type & (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID1 | |
| 2467 | BTRFS_BLOCK_GROUP_RAID10 | |
| 2468 | BTRFS_BLOCK_GROUP_DUP)) { |
| 2469 | /* we limit the length of each bio to what fits in a stripe */ |
| 2470 | *length = min_t(u64, em->len - offset, |
| 2471 | map->stripe_len - stripe_offset); |
| 2472 | } else { |
| 2473 | *length = em->len - offset; |
| 2474 | } |
| 2475 | |
| 2476 | if (!multi_ret && !unplug_page) |
| 2477 | goto out; |
| 2478 | |
| 2479 | num_stripes = 1; |
| 2480 | stripe_index = 0; |
| 2481 | if (map->type & BTRFS_BLOCK_GROUP_RAID1) { |
| 2482 | if (unplug_page || (rw & (1 << BIO_RW))) |
| 2483 | num_stripes = map->num_stripes; |
| 2484 | else if (mirror_num) |
| 2485 | stripe_index = mirror_num - 1; |
| 2486 | else { |
| 2487 | stripe_index = find_live_mirror(map, 0, |
| 2488 | map->num_stripes, |
| 2489 | current->pid % map->num_stripes); |
| 2490 | } |
| 2491 | |
| 2492 | } else if (map->type & BTRFS_BLOCK_GROUP_DUP) { |
| 2493 | if (rw & (1 << BIO_RW)) |
| 2494 | num_stripes = map->num_stripes; |
| 2495 | else if (mirror_num) |
| 2496 | stripe_index = mirror_num - 1; |
| 2497 | |
| 2498 | } else if (map->type & BTRFS_BLOCK_GROUP_RAID10) { |
| 2499 | int factor = map->num_stripes / map->sub_stripes; |
| 2500 | |
| 2501 | stripe_index = do_div(stripe_nr, factor); |
| 2502 | stripe_index *= map->sub_stripes; |
| 2503 | |
| 2504 | if (unplug_page || (rw & (1 << BIO_RW))) |
| 2505 | num_stripes = map->sub_stripes; |
| 2506 | else if (mirror_num) |
| 2507 | stripe_index += mirror_num - 1; |
| 2508 | else { |
| 2509 | stripe_index = find_live_mirror(map, stripe_index, |
| 2510 | map->sub_stripes, stripe_index + |
| 2511 | current->pid % map->sub_stripes); |
| 2512 | } |
| 2513 | } else { |
| 2514 | /* |
| 2515 | * after this do_div call, stripe_nr is the number of stripes |
| 2516 | * on this device we have to walk to find the data, and |
| 2517 | * stripe_index is the number of our device in the stripe array |
| 2518 | */ |
| 2519 | stripe_index = do_div(stripe_nr, map->num_stripes); |
| 2520 | } |
| 2521 | BUG_ON(stripe_index >= map->num_stripes); |
| 2522 | |
| 2523 | for (i = 0; i < num_stripes; i++) { |
| 2524 | if (unplug_page) { |
| 2525 | struct btrfs_device *device; |
| 2526 | struct backing_dev_info *bdi; |
| 2527 | |
| 2528 | device = map->stripes[stripe_index].dev; |
| 2529 | if (device->bdev) { |
| 2530 | bdi = blk_get_backing_dev_info(device->bdev); |
| 2531 | if (bdi->unplug_io_fn) |
| 2532 | bdi->unplug_io_fn(bdi, unplug_page); |
| 2533 | } |
| 2534 | } else { |
| 2535 | multi->stripes[i].physical = |
| 2536 | map->stripes[stripe_index].physical + |
| 2537 | stripe_offset + stripe_nr * map->stripe_len; |
| 2538 | multi->stripes[i].dev = map->stripes[stripe_index].dev; |
| 2539 | } |
| 2540 | stripe_index++; |
| 2541 | } |
| 2542 | if (multi_ret) { |
| 2543 | *multi_ret = multi; |
| 2544 | multi->num_stripes = num_stripes; |
| 2545 | multi->max_errors = max_errors; |
| 2546 | } |
| 2547 | out: |
| 2548 | free_extent_map(em); |
| 2549 | return 0; |
| 2550 | } |
| 2551 | |
| 2552 | int btrfs_map_block(struct btrfs_mapping_tree *map_tree, int rw, |
| 2553 | u64 logical, u64 *length, |
| 2554 | struct btrfs_multi_bio **multi_ret, int mirror_num) |
| 2555 | { |
| 2556 | return __btrfs_map_block(map_tree, rw, logical, length, multi_ret, |
| 2557 | mirror_num, NULL); |
| 2558 | } |
| 2559 | |
| 2560 | int btrfs_rmap_block(struct btrfs_mapping_tree *map_tree, |
| 2561 | u64 chunk_start, u64 physical, u64 devid, |
| 2562 | u64 **logical, int *naddrs, int *stripe_len) |
| 2563 | { |
| 2564 | struct extent_map_tree *em_tree = &map_tree->map_tree; |
| 2565 | struct extent_map *em; |
| 2566 | struct map_lookup *map; |
| 2567 | u64 *buf; |
| 2568 | u64 bytenr; |
| 2569 | u64 length; |
| 2570 | u64 stripe_nr; |
| 2571 | int i, j, nr = 0; |
| 2572 | |
| 2573 | spin_lock(&em_tree->lock); |
| 2574 | em = lookup_extent_mapping(em_tree, chunk_start, 1); |
| 2575 | spin_unlock(&em_tree->lock); |
| 2576 | |
| 2577 | BUG_ON(!em || em->start != chunk_start); |
| 2578 | map = (struct map_lookup *)em->bdev; |
| 2579 | |
| 2580 | length = em->len; |
| 2581 | if (map->type & BTRFS_BLOCK_GROUP_RAID10) |
| 2582 | do_div(length, map->num_stripes / map->sub_stripes); |
| 2583 | else if (map->type & BTRFS_BLOCK_GROUP_RAID0) |
| 2584 | do_div(length, map->num_stripes); |
| 2585 | |
| 2586 | buf = kzalloc(sizeof(u64) * map->num_stripes, GFP_NOFS); |
| 2587 | BUG_ON(!buf); |
| 2588 | |
| 2589 | for (i = 0; i < map->num_stripes; i++) { |
| 2590 | if (devid && map->stripes[i].dev->devid != devid) |
| 2591 | continue; |
| 2592 | if (map->stripes[i].physical > physical || |
| 2593 | map->stripes[i].physical + length <= physical) |
| 2594 | continue; |
| 2595 | |
| 2596 | stripe_nr = physical - map->stripes[i].physical; |
| 2597 | do_div(stripe_nr, map->stripe_len); |
| 2598 | |
| 2599 | if (map->type & BTRFS_BLOCK_GROUP_RAID10) { |
| 2600 | stripe_nr = stripe_nr * map->num_stripes + i; |
| 2601 | do_div(stripe_nr, map->sub_stripes); |
| 2602 | } else if (map->type & BTRFS_BLOCK_GROUP_RAID0) { |
| 2603 | stripe_nr = stripe_nr * map->num_stripes + i; |
| 2604 | } |
| 2605 | bytenr = chunk_start + stripe_nr * map->stripe_len; |
| 2606 | WARN_ON(nr >= map->num_stripes); |
| 2607 | for (j = 0; j < nr; j++) { |
| 2608 | if (buf[j] == bytenr) |
| 2609 | break; |
| 2610 | } |
| 2611 | if (j == nr) { |
| 2612 | WARN_ON(nr >= map->num_stripes); |
| 2613 | buf[nr++] = bytenr; |
| 2614 | } |
| 2615 | } |
| 2616 | |
| 2617 | for (i = 0; i > nr; i++) { |
| 2618 | struct btrfs_multi_bio *multi; |
| 2619 | struct btrfs_bio_stripe *stripe; |
| 2620 | int ret; |
| 2621 | |
| 2622 | length = 1; |
| 2623 | ret = btrfs_map_block(map_tree, WRITE, buf[i], |
| 2624 | &length, &multi, 0); |
| 2625 | BUG_ON(ret); |
| 2626 | |
| 2627 | stripe = multi->stripes; |
| 2628 | for (j = 0; j < multi->num_stripes; j++) { |
| 2629 | if (stripe->physical >= physical && |
| 2630 | physical < stripe->physical + length) |
| 2631 | break; |
| 2632 | } |
| 2633 | BUG_ON(j >= multi->num_stripes); |
| 2634 | kfree(multi); |
| 2635 | } |
| 2636 | |
| 2637 | *logical = buf; |
| 2638 | *naddrs = nr; |
| 2639 | *stripe_len = map->stripe_len; |
| 2640 | |
| 2641 | free_extent_map(em); |
| 2642 | return 0; |
| 2643 | } |
| 2644 | |
| 2645 | int btrfs_unplug_page(struct btrfs_mapping_tree *map_tree, |
| 2646 | u64 logical, struct page *page) |
| 2647 | { |
| 2648 | u64 length = PAGE_CACHE_SIZE; |
| 2649 | return __btrfs_map_block(map_tree, READ, logical, &length, |
| 2650 | NULL, 0, page); |
| 2651 | } |
| 2652 | |
| 2653 | static void end_bio_multi_stripe(struct bio *bio, int err) |
| 2654 | { |
| 2655 | struct btrfs_multi_bio *multi = bio->bi_private; |
| 2656 | int is_orig_bio = 0; |
| 2657 | |
| 2658 | if (err) |
| 2659 | atomic_inc(&multi->error); |
| 2660 | |
| 2661 | if (bio == multi->orig_bio) |
| 2662 | is_orig_bio = 1; |
| 2663 | |
| 2664 | if (atomic_dec_and_test(&multi->stripes_pending)) { |
| 2665 | if (!is_orig_bio) { |
| 2666 | bio_put(bio); |
| 2667 | bio = multi->orig_bio; |
| 2668 | } |
| 2669 | bio->bi_private = multi->private; |
| 2670 | bio->bi_end_io = multi->end_io; |
| 2671 | /* only send an error to the higher layers if it is |
| 2672 | * beyond the tolerance of the multi-bio |
| 2673 | */ |
| 2674 | if (atomic_read(&multi->error) > multi->max_errors) { |
| 2675 | err = -EIO; |
| 2676 | } else if (err) { |
| 2677 | /* |
| 2678 | * this bio is actually up to date, we didn't |
| 2679 | * go over the max number of errors |
| 2680 | */ |
| 2681 | set_bit(BIO_UPTODATE, &bio->bi_flags); |
| 2682 | err = 0; |
| 2683 | } |
| 2684 | kfree(multi); |
| 2685 | |
| 2686 | bio_endio(bio, err); |
| 2687 | } else if (!is_orig_bio) { |
| 2688 | bio_put(bio); |
| 2689 | } |
| 2690 | } |
| 2691 | |
| 2692 | struct async_sched { |
| 2693 | struct bio *bio; |
| 2694 | int rw; |
| 2695 | struct btrfs_fs_info *info; |
| 2696 | struct btrfs_work work; |
| 2697 | }; |
| 2698 | |
| 2699 | /* |
| 2700 | * see run_scheduled_bios for a description of why bios are collected for |
| 2701 | * async submit. |
| 2702 | * |
| 2703 | * This will add one bio to the pending list for a device and make sure |
| 2704 | * the work struct is scheduled. |
| 2705 | */ |
| 2706 | static noinline int schedule_bio(struct btrfs_root *root, |
| 2707 | struct btrfs_device *device, |
| 2708 | int rw, struct bio *bio) |
| 2709 | { |
| 2710 | int should_queue = 1; |
| 2711 | |
| 2712 | /* don't bother with additional async steps for reads, right now */ |
| 2713 | if (!(rw & (1 << BIO_RW))) { |
| 2714 | bio_get(bio); |
| 2715 | submit_bio(rw, bio); |
| 2716 | bio_put(bio); |
| 2717 | return 0; |
| 2718 | } |
| 2719 | |
| 2720 | /* |
| 2721 | * nr_async_bios allows us to reliably return congestion to the |
| 2722 | * higher layers. Otherwise, the async bio makes it appear we have |
| 2723 | * made progress against dirty pages when we've really just put it |
| 2724 | * on a queue for later |
| 2725 | */ |
| 2726 | atomic_inc(&root->fs_info->nr_async_bios); |
| 2727 | WARN_ON(bio->bi_next); |
| 2728 | bio->bi_next = NULL; |
| 2729 | bio->bi_rw |= rw; |
| 2730 | |
| 2731 | spin_lock(&device->io_lock); |
| 2732 | |
| 2733 | if (device->pending_bio_tail) |
| 2734 | device->pending_bio_tail->bi_next = bio; |
| 2735 | |
| 2736 | device->pending_bio_tail = bio; |
| 2737 | if (!device->pending_bios) |
| 2738 | device->pending_bios = bio; |
| 2739 | if (device->running_pending) |
| 2740 | should_queue = 0; |
| 2741 | |
| 2742 | spin_unlock(&device->io_lock); |
| 2743 | |
| 2744 | if (should_queue) |
| 2745 | btrfs_queue_worker(&root->fs_info->submit_workers, |
| 2746 | &device->work); |
| 2747 | return 0; |
| 2748 | } |
| 2749 | |
| 2750 | int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio, |
| 2751 | int mirror_num, int async_submit) |
| 2752 | { |
| 2753 | struct btrfs_mapping_tree *map_tree; |
| 2754 | struct btrfs_device *dev; |
| 2755 | struct bio *first_bio = bio; |
| 2756 | u64 logical = (u64)bio->bi_sector << 9; |
| 2757 | u64 length = 0; |
| 2758 | u64 map_length; |
| 2759 | struct btrfs_multi_bio *multi = NULL; |
| 2760 | int ret; |
| 2761 | int dev_nr = 0; |
| 2762 | int total_devs = 1; |
| 2763 | |
| 2764 | length = bio->bi_size; |
| 2765 | map_tree = &root->fs_info->mapping_tree; |
| 2766 | map_length = length; |
| 2767 | |
| 2768 | ret = btrfs_map_block(map_tree, rw, logical, &map_length, &multi, |
| 2769 | mirror_num); |
| 2770 | BUG_ON(ret); |
| 2771 | |
| 2772 | total_devs = multi->num_stripes; |
| 2773 | if (map_length < length) { |
| 2774 | printk(KERN_CRIT "mapping failed logical %llu bio len %llu " |
| 2775 | "len %llu\n", (unsigned long long)logical, |
| 2776 | (unsigned long long)length, |
| 2777 | (unsigned long long)map_length); |
| 2778 | BUG(); |
| 2779 | } |
| 2780 | multi->end_io = first_bio->bi_end_io; |
| 2781 | multi->private = first_bio->bi_private; |
| 2782 | multi->orig_bio = first_bio; |
| 2783 | atomic_set(&multi->stripes_pending, multi->num_stripes); |
| 2784 | |
| 2785 | while (dev_nr < total_devs) { |
| 2786 | if (total_devs > 1) { |
| 2787 | if (dev_nr < total_devs - 1) { |
| 2788 | bio = bio_clone(first_bio, GFP_NOFS); |
| 2789 | BUG_ON(!bio); |
| 2790 | } else { |
| 2791 | bio = first_bio; |
| 2792 | } |
| 2793 | bio->bi_private = multi; |
| 2794 | bio->bi_end_io = end_bio_multi_stripe; |
| 2795 | } |
| 2796 | bio->bi_sector = multi->stripes[dev_nr].physical >> 9; |
| 2797 | dev = multi->stripes[dev_nr].dev; |
| 2798 | BUG_ON(rw == WRITE && !dev->writeable); |
| 2799 | if (dev && dev->bdev) { |
| 2800 | bio->bi_bdev = dev->bdev; |
| 2801 | if (async_submit) |
| 2802 | schedule_bio(root, dev, rw, bio); |
| 2803 | else |
| 2804 | submit_bio(rw, bio); |
| 2805 | } else { |
| 2806 | bio->bi_bdev = root->fs_info->fs_devices->latest_bdev; |
| 2807 | bio->bi_sector = logical >> 9; |
| 2808 | bio_endio(bio, -EIO); |
| 2809 | } |
| 2810 | dev_nr++; |
| 2811 | } |
| 2812 | if (total_devs == 1) |
| 2813 | kfree(multi); |
| 2814 | return 0; |
| 2815 | } |
| 2816 | |
| 2817 | struct btrfs_device *btrfs_find_device(struct btrfs_root *root, u64 devid, |
| 2818 | u8 *uuid, u8 *fsid) |
| 2819 | { |
| 2820 | struct btrfs_device *device; |
| 2821 | struct btrfs_fs_devices *cur_devices; |
| 2822 | |
| 2823 | cur_devices = root->fs_info->fs_devices; |
| 2824 | while (cur_devices) { |
| 2825 | if (!fsid || |
| 2826 | !memcmp(cur_devices->fsid, fsid, BTRFS_UUID_SIZE)) { |
| 2827 | device = __find_device(&cur_devices->devices, |
| 2828 | devid, uuid); |
| 2829 | if (device) |
| 2830 | return device; |
| 2831 | } |
| 2832 | cur_devices = cur_devices->seed; |
| 2833 | } |
| 2834 | return NULL; |
| 2835 | } |
| 2836 | |
| 2837 | static struct btrfs_device *add_missing_dev(struct btrfs_root *root, |
| 2838 | u64 devid, u8 *dev_uuid) |
| 2839 | { |
| 2840 | struct btrfs_device *device; |
| 2841 | struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices; |
| 2842 | |
| 2843 | device = kzalloc(sizeof(*device), GFP_NOFS); |
| 2844 | if (!device) |
| 2845 | return NULL; |
| 2846 | list_add(&device->dev_list, |
| 2847 | &fs_devices->devices); |
| 2848 | device->barriers = 1; |
| 2849 | device->dev_root = root->fs_info->dev_root; |
| 2850 | device->devid = devid; |
| 2851 | device->work.func = pending_bios_fn; |
| 2852 | device->fs_devices = fs_devices; |
| 2853 | fs_devices->num_devices++; |
| 2854 | spin_lock_init(&device->io_lock); |
| 2855 | INIT_LIST_HEAD(&device->dev_alloc_list); |
| 2856 | memcpy(device->uuid, dev_uuid, BTRFS_UUID_SIZE); |
| 2857 | return device; |
| 2858 | } |
| 2859 | |
| 2860 | static int read_one_chunk(struct btrfs_root *root, struct btrfs_key *key, |
| 2861 | struct extent_buffer *leaf, |
| 2862 | struct btrfs_chunk *chunk) |
| 2863 | { |
| 2864 | struct btrfs_mapping_tree *map_tree = &root->fs_info->mapping_tree; |
| 2865 | struct map_lookup *map; |
| 2866 | struct extent_map *em; |
| 2867 | u64 logical; |
| 2868 | u64 length; |
| 2869 | u64 devid; |
| 2870 | u8 uuid[BTRFS_UUID_SIZE]; |
| 2871 | int num_stripes; |
| 2872 | int ret; |
| 2873 | int i; |
| 2874 | |
| 2875 | logical = key->offset; |
| 2876 | length = btrfs_chunk_length(leaf, chunk); |
| 2877 | |
| 2878 | spin_lock(&map_tree->map_tree.lock); |
| 2879 | em = lookup_extent_mapping(&map_tree->map_tree, logical, 1); |
| 2880 | spin_unlock(&map_tree->map_tree.lock); |
| 2881 | |
| 2882 | /* already mapped? */ |
| 2883 | if (em && em->start <= logical && em->start + em->len > logical) { |
| 2884 | free_extent_map(em); |
| 2885 | return 0; |
| 2886 | } else if (em) { |
| 2887 | free_extent_map(em); |
| 2888 | } |
| 2889 | |
| 2890 | map = kzalloc(sizeof(*map), GFP_NOFS); |
| 2891 | if (!map) |
| 2892 | return -ENOMEM; |
| 2893 | |
| 2894 | em = alloc_extent_map(GFP_NOFS); |
| 2895 | if (!em) |
| 2896 | return -ENOMEM; |
| 2897 | num_stripes = btrfs_chunk_num_stripes(leaf, chunk); |
| 2898 | map = kmalloc(map_lookup_size(num_stripes), GFP_NOFS); |
| 2899 | if (!map) { |
| 2900 | free_extent_map(em); |
| 2901 | return -ENOMEM; |
| 2902 | } |
| 2903 | |
| 2904 | em->bdev = (struct block_device *)map; |
| 2905 | em->start = logical; |
| 2906 | em->len = length; |
| 2907 | em->block_start = 0; |
| 2908 | em->block_len = em->len; |
| 2909 | |
| 2910 | map->num_stripes = num_stripes; |
| 2911 | map->io_width = btrfs_chunk_io_width(leaf, chunk); |
| 2912 | map->io_align = btrfs_chunk_io_align(leaf, chunk); |
| 2913 | map->sector_size = btrfs_chunk_sector_size(leaf, chunk); |
| 2914 | map->stripe_len = btrfs_chunk_stripe_len(leaf, chunk); |
| 2915 | map->type = btrfs_chunk_type(leaf, chunk); |
| 2916 | map->sub_stripes = btrfs_chunk_sub_stripes(leaf, chunk); |
| 2917 | for (i = 0; i < num_stripes; i++) { |
| 2918 | map->stripes[i].physical = |
| 2919 | btrfs_stripe_offset_nr(leaf, chunk, i); |
| 2920 | devid = btrfs_stripe_devid_nr(leaf, chunk, i); |
| 2921 | read_extent_buffer(leaf, uuid, (unsigned long) |
| 2922 | btrfs_stripe_dev_uuid_nr(chunk, i), |
| 2923 | BTRFS_UUID_SIZE); |
| 2924 | map->stripes[i].dev = btrfs_find_device(root, devid, uuid, |
| 2925 | NULL); |
| 2926 | if (!map->stripes[i].dev && !btrfs_test_opt(root, DEGRADED)) { |
| 2927 | kfree(map); |
| 2928 | free_extent_map(em); |
| 2929 | return -EIO; |
| 2930 | } |
| 2931 | if (!map->stripes[i].dev) { |
| 2932 | map->stripes[i].dev = |
| 2933 | add_missing_dev(root, devid, uuid); |
| 2934 | if (!map->stripes[i].dev) { |
| 2935 | kfree(map); |
| 2936 | free_extent_map(em); |
| 2937 | return -EIO; |
| 2938 | } |
| 2939 | } |
| 2940 | map->stripes[i].dev->in_fs_metadata = 1; |
| 2941 | } |
| 2942 | |
| 2943 | spin_lock(&map_tree->map_tree.lock); |
| 2944 | ret = add_extent_mapping(&map_tree->map_tree, em); |
| 2945 | spin_unlock(&map_tree->map_tree.lock); |
| 2946 | BUG_ON(ret); |
| 2947 | free_extent_map(em); |
| 2948 | |
| 2949 | return 0; |
| 2950 | } |
| 2951 | |
| 2952 | static int fill_device_from_item(struct extent_buffer *leaf, |
| 2953 | struct btrfs_dev_item *dev_item, |
| 2954 | struct btrfs_device *device) |
| 2955 | { |
| 2956 | unsigned long ptr; |
| 2957 | |
| 2958 | device->devid = btrfs_device_id(leaf, dev_item); |
| 2959 | device->total_bytes = btrfs_device_total_bytes(leaf, dev_item); |
| 2960 | device->bytes_used = btrfs_device_bytes_used(leaf, dev_item); |
| 2961 | device->type = btrfs_device_type(leaf, dev_item); |
| 2962 | device->io_align = btrfs_device_io_align(leaf, dev_item); |
| 2963 | device->io_width = btrfs_device_io_width(leaf, dev_item); |
| 2964 | device->sector_size = btrfs_device_sector_size(leaf, dev_item); |
| 2965 | |
| 2966 | ptr = (unsigned long)btrfs_device_uuid(dev_item); |
| 2967 | read_extent_buffer(leaf, device->uuid, ptr, BTRFS_UUID_SIZE); |
| 2968 | |
| 2969 | return 0; |
| 2970 | } |
| 2971 | |
| 2972 | static int open_seed_devices(struct btrfs_root *root, u8 *fsid) |
| 2973 | { |
| 2974 | struct btrfs_fs_devices *fs_devices; |
| 2975 | int ret; |
| 2976 | |
| 2977 | mutex_lock(&uuid_mutex); |
| 2978 | |
| 2979 | fs_devices = root->fs_info->fs_devices->seed; |
| 2980 | while (fs_devices) { |
| 2981 | if (!memcmp(fs_devices->fsid, fsid, BTRFS_UUID_SIZE)) { |
| 2982 | ret = 0; |
| 2983 | goto out; |
| 2984 | } |
| 2985 | fs_devices = fs_devices->seed; |
| 2986 | } |
| 2987 | |
| 2988 | fs_devices = find_fsid(fsid); |
| 2989 | if (!fs_devices) { |
| 2990 | ret = -ENOENT; |
| 2991 | goto out; |
| 2992 | } |
| 2993 | |
| 2994 | fs_devices = clone_fs_devices(fs_devices); |
| 2995 | if (IS_ERR(fs_devices)) { |
| 2996 | ret = PTR_ERR(fs_devices); |
| 2997 | goto out; |
| 2998 | } |
| 2999 | |
| 3000 | ret = __btrfs_open_devices(fs_devices, FMODE_READ, |
| 3001 | root->fs_info->bdev_holder); |
| 3002 | if (ret) |
| 3003 | goto out; |
| 3004 | |
| 3005 | if (!fs_devices->seeding) { |
| 3006 | __btrfs_close_devices(fs_devices); |
| 3007 | free_fs_devices(fs_devices); |
| 3008 | ret = -EINVAL; |
| 3009 | goto out; |
| 3010 | } |
| 3011 | |
| 3012 | fs_devices->seed = root->fs_info->fs_devices->seed; |
| 3013 | root->fs_info->fs_devices->seed = fs_devices; |
| 3014 | out: |
| 3015 | mutex_unlock(&uuid_mutex); |
| 3016 | return ret; |
| 3017 | } |
| 3018 | |
| 3019 | static int read_one_dev(struct btrfs_root *root, |
| 3020 | struct extent_buffer *leaf, |
| 3021 | struct btrfs_dev_item *dev_item) |
| 3022 | { |
| 3023 | struct btrfs_device *device; |
| 3024 | u64 devid; |
| 3025 | int ret; |
| 3026 | u8 fs_uuid[BTRFS_UUID_SIZE]; |
| 3027 | u8 dev_uuid[BTRFS_UUID_SIZE]; |
| 3028 | |
| 3029 | devid = btrfs_device_id(leaf, dev_item); |
| 3030 | read_extent_buffer(leaf, dev_uuid, |
| 3031 | (unsigned long)btrfs_device_uuid(dev_item), |
| 3032 | BTRFS_UUID_SIZE); |
| 3033 | read_extent_buffer(leaf, fs_uuid, |
| 3034 | (unsigned long)btrfs_device_fsid(dev_item), |
| 3035 | BTRFS_UUID_SIZE); |
| 3036 | |
| 3037 | if (memcmp(fs_uuid, root->fs_info->fsid, BTRFS_UUID_SIZE)) { |
| 3038 | ret = open_seed_devices(root, fs_uuid); |
| 3039 | if (ret && !btrfs_test_opt(root, DEGRADED)) |
| 3040 | return ret; |
| 3041 | } |
| 3042 | |
| 3043 | device = btrfs_find_device(root, devid, dev_uuid, fs_uuid); |
| 3044 | if (!device || !device->bdev) { |
| 3045 | if (!btrfs_test_opt(root, DEGRADED)) |
| 3046 | return -EIO; |
| 3047 | |
| 3048 | if (!device) { |
| 3049 | printk(KERN_WARNING "warning devid %llu missing\n", |
| 3050 | (unsigned long long)devid); |
| 3051 | device = add_missing_dev(root, devid, dev_uuid); |
| 3052 | if (!device) |
| 3053 | return -ENOMEM; |
| 3054 | } |
| 3055 | } |
| 3056 | |
| 3057 | if (device->fs_devices != root->fs_info->fs_devices) { |
| 3058 | BUG_ON(device->writeable); |
| 3059 | if (device->generation != |
| 3060 | btrfs_device_generation(leaf, dev_item)) |
| 3061 | return -EINVAL; |
| 3062 | } |
| 3063 | |
| 3064 | fill_device_from_item(leaf, dev_item, device); |
| 3065 | device->dev_root = root->fs_info->dev_root; |
| 3066 | device->in_fs_metadata = 1; |
| 3067 | if (device->writeable) |
| 3068 | device->fs_devices->total_rw_bytes += device->total_bytes; |
| 3069 | ret = 0; |
| 3070 | return ret; |
| 3071 | } |
| 3072 | |
| 3073 | int btrfs_read_super_device(struct btrfs_root *root, struct extent_buffer *buf) |
| 3074 | { |
| 3075 | struct btrfs_dev_item *dev_item; |
| 3076 | |
| 3077 | dev_item = (struct btrfs_dev_item *)offsetof(struct btrfs_super_block, |
| 3078 | dev_item); |
| 3079 | return read_one_dev(root, buf, dev_item); |
| 3080 | } |
| 3081 | |
| 3082 | int btrfs_read_sys_array(struct btrfs_root *root) |
| 3083 | { |
| 3084 | struct btrfs_super_block *super_copy = &root->fs_info->super_copy; |
| 3085 | struct extent_buffer *sb; |
| 3086 | struct btrfs_disk_key *disk_key; |
| 3087 | struct btrfs_chunk *chunk; |
| 3088 | u8 *ptr; |
| 3089 | unsigned long sb_ptr; |
| 3090 | int ret = 0; |
| 3091 | u32 num_stripes; |
| 3092 | u32 array_size; |
| 3093 | u32 len = 0; |
| 3094 | u32 cur; |
| 3095 | struct btrfs_key key; |
| 3096 | |
| 3097 | sb = btrfs_find_create_tree_block(root, BTRFS_SUPER_INFO_OFFSET, |
| 3098 | BTRFS_SUPER_INFO_SIZE); |
| 3099 | if (!sb) |
| 3100 | return -ENOMEM; |
| 3101 | btrfs_set_buffer_uptodate(sb); |
| 3102 | write_extent_buffer(sb, super_copy, 0, BTRFS_SUPER_INFO_SIZE); |
| 3103 | array_size = btrfs_super_sys_array_size(super_copy); |
| 3104 | |
| 3105 | ptr = super_copy->sys_chunk_array; |
| 3106 | sb_ptr = offsetof(struct btrfs_super_block, sys_chunk_array); |
| 3107 | cur = 0; |
| 3108 | |
| 3109 | while (cur < array_size) { |
| 3110 | disk_key = (struct btrfs_disk_key *)ptr; |
| 3111 | btrfs_disk_key_to_cpu(&key, disk_key); |
| 3112 | |
| 3113 | len = sizeof(*disk_key); ptr += len; |
| 3114 | sb_ptr += len; |
| 3115 | cur += len; |
| 3116 | |
| 3117 | if (key.type == BTRFS_CHUNK_ITEM_KEY) { |
| 3118 | chunk = (struct btrfs_chunk *)sb_ptr; |
| 3119 | ret = read_one_chunk(root, &key, sb, chunk); |
| 3120 | if (ret) |
| 3121 | break; |
| 3122 | num_stripes = btrfs_chunk_num_stripes(sb, chunk); |
| 3123 | len = btrfs_chunk_item_size(num_stripes); |
| 3124 | } else { |
| 3125 | ret = -EIO; |
| 3126 | break; |
| 3127 | } |
| 3128 | ptr += len; |
| 3129 | sb_ptr += len; |
| 3130 | cur += len; |
| 3131 | } |
| 3132 | free_extent_buffer(sb); |
| 3133 | return ret; |
| 3134 | } |
| 3135 | |
| 3136 | int btrfs_read_chunk_tree(struct btrfs_root *root) |
| 3137 | { |
| 3138 | struct btrfs_path *path; |
| 3139 | struct extent_buffer *leaf; |
| 3140 | struct btrfs_key key; |
| 3141 | struct btrfs_key found_key; |
| 3142 | int ret; |
| 3143 | int slot; |
| 3144 | |
| 3145 | root = root->fs_info->chunk_root; |
| 3146 | |
| 3147 | path = btrfs_alloc_path(); |
| 3148 | if (!path) |
| 3149 | return -ENOMEM; |
| 3150 | |
| 3151 | /* first we search for all of the device items, and then we |
| 3152 | * read in all of the chunk items. This way we can create chunk |
| 3153 | * mappings that reference all of the devices that are afound |
| 3154 | */ |
| 3155 | key.objectid = BTRFS_DEV_ITEMS_OBJECTID; |
| 3156 | key.offset = 0; |
| 3157 | key.type = 0; |
| 3158 | again: |
| 3159 | ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); |
| 3160 | while (1) { |
| 3161 | leaf = path->nodes[0]; |
| 3162 | slot = path->slots[0]; |
| 3163 | if (slot >= btrfs_header_nritems(leaf)) { |
| 3164 | ret = btrfs_next_leaf(root, path); |
| 3165 | if (ret == 0) |
| 3166 | continue; |
| 3167 | if (ret < 0) |
| 3168 | goto error; |
| 3169 | break; |
| 3170 | } |
| 3171 | btrfs_item_key_to_cpu(leaf, &found_key, slot); |
| 3172 | if (key.objectid == BTRFS_DEV_ITEMS_OBJECTID) { |
| 3173 | if (found_key.objectid != BTRFS_DEV_ITEMS_OBJECTID) |
| 3174 | break; |
| 3175 | if (found_key.type == BTRFS_DEV_ITEM_KEY) { |
| 3176 | struct btrfs_dev_item *dev_item; |
| 3177 | dev_item = btrfs_item_ptr(leaf, slot, |
| 3178 | struct btrfs_dev_item); |
| 3179 | ret = read_one_dev(root, leaf, dev_item); |
| 3180 | if (ret) |
| 3181 | goto error; |
| 3182 | } |
| 3183 | } else if (found_key.type == BTRFS_CHUNK_ITEM_KEY) { |
| 3184 | struct btrfs_chunk *chunk; |
| 3185 | chunk = btrfs_item_ptr(leaf, slot, struct btrfs_chunk); |
| 3186 | ret = read_one_chunk(root, &found_key, leaf, chunk); |
| 3187 | if (ret) |
| 3188 | goto error; |
| 3189 | } |
| 3190 | path->slots[0]++; |
| 3191 | } |
| 3192 | if (key.objectid == BTRFS_DEV_ITEMS_OBJECTID) { |
| 3193 | key.objectid = 0; |
| 3194 | btrfs_release_path(root, path); |
| 3195 | goto again; |
| 3196 | } |
| 3197 | ret = 0; |
| 3198 | error: |
| 3199 | btrfs_free_path(path); |
| 3200 | return ret; |
| 3201 | } |