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Btrfs: simplify iteration codes
[linux-2.6-block.git] / fs / btrfs / volumes.c
CommitLineData
0b86a832
CM		 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>
8a4b83cc 20#include <linux/buffer_head.h>
f2d8d74d 21#include <linux/blkdev.h>
788f20eb 22#include <linux/random.h>
593060d7 23#include <asm/div64.h>
4b4e25f2 24#include "compat.h"
0b86a832
CM		 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"
8b712842 31#include "async-thread.h"
0b86a832 32
593060d7
CM		 33struct 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;
321aecc6 40 int sub_stripes;
cea9e445 41 struct btrfs_bio_stripe stripes[];
593060d7
CM		 42};
43
2b82032c
YZ		 44static int init_first_rw_device(struct btrfs_trans_handle *trans,
45 struct btrfs_root *root,
46 struct btrfs_device *device);
47static int btrfs_relocate_sys_chunks(struct btrfs_root *root);
48
593060d7 49#define map_lookup_size(n) (sizeof(struct map_lookup) + \
cea9e445 50 (sizeof(struct btrfs_bio_stripe) * (n)))
593060d7 51
8a4b83cc
CM		 52static DEFINE_MUTEX(uuid_mutex);
53static LIST_HEAD(fs_uuids);
54
a061fc8d
CM		 55void btrfs_lock_volumes(void)
56{
57 mutex_lock(&uuid_mutex);
58}
59
60void btrfs_unlock_volumes(void)
61{
62 mutex_unlock(&uuid_mutex);
63}
64
7d9eb12c
CM		 65static void lock_chunks(struct btrfs_root *root)
66{
7d9eb12c
CM		 67 mutex_lock(&root->fs_info->chunk_mutex);
68}
69
70static void unlock_chunks(struct btrfs_root *root)
71{
7d9eb12c
CM		 72 mutex_unlock(&root->fs_info->chunk_mutex);
73}
74
e4404d6e
YZ		 75static 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
8a4b83cc
CM		 89int btrfs_cleanup_fs_uuids(void)
90{
91 struct btrfs_fs_devices *fs_devices;
8a4b83cc 92
2b82032c
YZ		 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);
e4404d6e 97 free_fs_devices(fs_devices);
8a4b83cc
CM		 98 }
99 return 0;
100}
101
a1b32a59
CM		 102static noinline struct btrfs_device *__find_device(struct list_head *head,
103 u64 devid, u8 *uuid)
8a4b83cc
CM		 104{
105 struct btrfs_device *dev;
8a4b83cc 106
c6e30871 107 list_for_each_entry(dev, head, dev_list) {
a443755f 108 if (dev->devid == devid &&
8f18cf13 109 (!uuid || !memcmp(dev->uuid, uuid, BTRFS_UUID_SIZE))) {
8a4b83cc 110 return dev;
a443755f 111 }
8a4b83cc
CM		 112 }
113 return NULL;
114}
115
a1b32a59 116static noinline struct btrfs_fs_devices *find_fsid(u8 *fsid)
8a4b83cc 117{
8a4b83cc
CM		 118 struct btrfs_fs_devices *fs_devices;
119
c6e30871 120 list_for_each_entry(fs_devices, &fs_uuids, list) {
8a4b83cc
CM		 121 if (memcmp(fsid, fs_devices->fsid, BTRFS_FSID_SIZE) == 0)
122 return fs_devices;
123 }
124 return NULL;
125}
126
8b712842
CM		 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 */
d397712b 138static noinline int run_scheduled_bios(struct btrfs_device *device)
8b712842
CM		 139{
140 struct bio *pending;
141 struct backing_dev_info *bdi;
b64a2851 142 struct btrfs_fs_info *fs_info;
8b712842
CM		 143 struct bio *tail;
144 struct bio *cur;
145 int again = 0;
146 unsigned long num_run = 0;
b64a2851 147 unsigned long limit;
8b712842
CM		 148
149 bdi = device->bdev->bd_inode->i_mapping->backing_dev_info;
b64a2851
CM		 150 fs_info = device->dev_root->fs_info;
151 limit = btrfs_async_submit_limit(fs_info);
152 limit = limit * 2 / 3;
153
8b712842
CM		 154loop:
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
d397712b 185 while (pending) {
8b712842
CM		 186 cur = pending;
187 pending = pending->bi_next;
188 cur->bi_next = NULL;
b64a2851
CM		 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);
492bb6de
CM		 194
195 BUG_ON(atomic_read(&cur->bi_cnt) == 0);
196 bio_get(cur);
8b712842 197 submit_bio(cur->bi_rw, cur);
492bb6de 198 bio_put(cur);
8b712842
CM		 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 */
5f2cc086
CM		 206 if (pending && bdi_write_congested(bdi) &&
207 fs_info->fs_devices->open_devices > 1) {
8b712842
CM		 208 struct bio *old_head;
209
210 spin_lock(&device->io_lock);
492bb6de 211
8b712842
CM		 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;
1d9e2ae9 218 device->running_pending = 0;
8b712842
CM		 219
220 spin_unlock(&device->io_lock);
221 btrfs_requeue_work(&device->work);
222 goto done;
223 }
224 }
225 if (again)
226 goto loop;
227done:
228 return 0;
229}
230
b2950863 231static void pending_bios_fn(struct btrfs_work *work)
8b712842
CM		 232{
233 struct btrfs_device *device;
234
235 device = container_of(work, struct btrfs_device, work);
236 run_scheduled_bios(device);
237}
238
a1b32a59 239static noinline int device_list_add(const char *path,
8a4b83cc
CM		 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) {
515dc322 249 fs_devices = kzalloc(sizeof(*fs_devices), GFP_NOFS);
8a4b83cc
CM		 250 if (!fs_devices)
251 return -ENOMEM;
252 INIT_LIST_HEAD(&fs_devices->devices);
b3075717 253 INIT_LIST_HEAD(&fs_devices->alloc_list);
8a4b83cc
CM		 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;
8a4b83cc
CM		 258 device = NULL;
259 } else {
a443755f
CM		 260 device = __find_device(&fs_devices->devices, devid,
261 disk_super->dev_item.uuid);
8a4b83cc
CM		 262 }
263 if (!device) {
2b82032c
YZ		 264 if (fs_devices->opened)
265 return -EBUSY;
266
8a4b83cc
CM		 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;
8b712842 273 device->work.func = pending_bios_fn;
a443755f
CM		 274 memcpy(device->uuid, disk_super->dev_item.uuid,
275 BTRFS_UUID_SIZE);
f2984462 276 device->barriers = 1;
b248a415 277 spin_lock_init(&device->io_lock);
8a4b83cc
CM		 278 device->name = kstrdup(path, GFP_NOFS);
279 if (!device->name) {
280 kfree(device);
281 return -ENOMEM;
282 }
2b82032c 283 INIT_LIST_HEAD(&device->dev_alloc_list);
8a4b83cc 284 list_add(&device->dev_list, &fs_devices->devices);
2b82032c 285 device->fs_devices = fs_devices;
8a4b83cc
CM		 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 }
8a4b83cc
CM		 293 *fs_devices_ret = fs_devices;
294 return 0;
295}
296
e4404d6e
YZ		 297static 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;
336error:
337 free_fs_devices(fs_devices);
338 return ERR_PTR(-ENOMEM);
339}
340
dfe25020
CM		 341int btrfs_close_extra_devices(struct btrfs_fs_devices *fs_devices)
342{
c6e30871 343 struct btrfs_device *device, *next;
dfe25020
CM		 344
345 mutex_lock(&uuid_mutex);
346again:
c6e30871 347 list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) {
2b82032c
YZ		 348 if (device->in_fs_metadata)
349 continue;
350
351 if (device->bdev) {
15916de8 352 close_bdev_exclusive(device->bdev, device->mode);
2b82032c
YZ		 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 }
e4404d6e
YZ		 361 list_del_init(&device->dev_list);
362 fs_devices->num_devices--;
363 kfree(device->name);
364 kfree(device);
dfe25020 365 }
2b82032c
YZ		 366
367 if (fs_devices->seed) {
368 fs_devices = fs_devices->seed;
2b82032c
YZ		 369 goto again;
370 }
371
dfe25020
CM		 372 mutex_unlock(&uuid_mutex);
373 return 0;
374}
a0af469b 375
2b82032c 376static int __btrfs_close_devices(struct btrfs_fs_devices *fs_devices)
8a4b83cc 377{
8a4b83cc 378 struct btrfs_device *device;
e4404d6e 379
2b82032c
YZ		 380 if (--fs_devices->opened > 0)
381 return 0;
8a4b83cc 382
c6e30871 383 list_for_each_entry(device, &fs_devices->devices, dev_list) {
8a4b83cc 384 if (device->bdev) {
15916de8 385 close_bdev_exclusive(device->bdev, device->mode);
a0af469b 386 fs_devices->open_devices--;
8a4b83cc 387 }
2b82032c
YZ		 388 if (device->writeable) {
389 list_del_init(&device->dev_alloc_list);
390 fs_devices->rw_devices--;
391 }
392
8a4b83cc 393 device->bdev = NULL;
2b82032c 394 device->writeable = 0;
dfe25020 395 device->in_fs_metadata = 0;
8a4b83cc 396 }
e4404d6e
YZ		 397 WARN_ON(fs_devices->open_devices);
398 WARN_ON(fs_devices->rw_devices);
2b82032c
YZ		 399 fs_devices->opened = 0;
400 fs_devices->seeding = 0;
2b82032c 401
8a4b83cc
CM		 402 return 0;
403}
404
2b82032c
YZ		 405int btrfs_close_devices(struct btrfs_fs_devices *fs_devices)
406{
e4404d6e 407 struct btrfs_fs_devices *seed_devices = NULL;
2b82032c
YZ		 408 int ret;
409
410 mutex_lock(&uuid_mutex);
411 ret = __btrfs_close_devices(fs_devices);
e4404d6e
YZ		 412 if (!fs_devices->opened) {
413 seed_devices = fs_devices->seed;
414 fs_devices->seed = NULL;
415 }
2b82032c 416 mutex_unlock(&uuid_mutex);
e4404d6e
YZ		 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 }
2b82032c
YZ		 424 return ret;
425}
426
e4404d6e
YZ		 427static int __btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
428 fmode_t flags, void *holder)
8a4b83cc
CM		 429{
430 struct block_device *bdev;
431 struct list_head *head = &fs_devices->devices;
8a4b83cc 432 struct btrfs_device *device;
a0af469b
CM		 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;
a0af469b 438 u64 devid;
2b82032c 439 int seeding = 1;
a0af469b 440 int ret = 0;
8a4b83cc 441
c6e30871 442 list_for_each_entry(device, head, dev_list) {
c1c4d91c
CM		 443 if (device->bdev)
444 continue;
dfe25020
CM		 445 if (!device->name)
446 continue;
447
15916de8 448 bdev = open_bdev_exclusive(device->name, flags, holder);
8a4b83cc 449 if (IS_ERR(bdev)) {
d397712b 450 printk(KERN_INFO "open %s failed\n", device->name);
a0af469b 451 goto error;
8a4b83cc 452 }
a061fc8d 453 set_blocksize(bdev, 4096);
a0af469b 454
a512bbf8 455 bh = btrfs_read_dev_super(bdev);
a0af469b
CM		 456 if (!bh)
457 goto error_close;
458
459 disk_super = (struct btrfs_super_block *)bh->b_data;
a0af469b
CM		 460 devid = le64_to_cpu(disk_super->dev_item.devid);
461 if (devid != device->devid)
462 goto error_brelse;
463
2b82032c
YZ		 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) {
a0af469b 470 latest_devid = devid;
2b82032c 471 latest_transid = device->generation;
a0af469b
CM		 472 latest_bdev = bdev;
473 }
474
2b82032c
YZ		 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
8a4b83cc 482 device->bdev = bdev;
dfe25020 483 device->in_fs_metadata = 0;
15916de8
CM		 484 device->mode = flags;
485
a0af469b 486 fs_devices->open_devices++;
2b82032c
YZ		 487 if (device->writeable) {
488 fs_devices->rw_devices++;
489 list_add(&device->dev_alloc_list,
490 &fs_devices->alloc_list);
491 }
a0af469b 492 continue;
a061fc8d 493
a0af469b
CM		 494error_brelse:
495 brelse(bh);
496error_close:
97288f2c 497 close_bdev_exclusive(bdev, FMODE_READ);
a0af469b
CM		 498error:
499 continue;
8a4b83cc 500 }
a0af469b
CM		 501 if (fs_devices->open_devices == 0) {
502 ret = -EIO;
503 goto out;
504 }
2b82032c
YZ		 505 fs_devices->seeding = seeding;
506 fs_devices->opened = 1;
a0af469b
CM		 507 fs_devices->latest_bdev = latest_bdev;
508 fs_devices->latest_devid = latest_devid;
509 fs_devices->latest_trans = latest_transid;
2b82032c 510 fs_devices->total_rw_bytes = 0;
a0af469b 511out:
2b82032c
YZ		 512 return ret;
513}
514
515int btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
97288f2c 516 fmode_t flags, void *holder)
2b82032c
YZ		 517{
518 int ret;
519
520 mutex_lock(&uuid_mutex);
521 if (fs_devices->opened) {
e4404d6e
YZ		 522 fs_devices->opened++;
523 ret = 0;
2b82032c 524 } else {
15916de8 525 ret = __btrfs_open_devices(fs_devices, flags, holder);
2b82032c 526 }
8a4b83cc 527 mutex_unlock(&uuid_mutex);
8a4b83cc
CM		 528 return ret;
529}
530
97288f2c 531int btrfs_scan_one_device(const char *path, fmode_t flags, void *holder,
8a4b83cc
CM		 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;
f2984462 539 u64 transid;
8a4b83cc
CM		 540
541 mutex_lock(&uuid_mutex);
542
15916de8 543 bdev = open_bdev_exclusive(path, flags, holder);
8a4b83cc
CM		 544
545 if (IS_ERR(bdev)) {
8a4b83cc
CM		 546 ret = PTR_ERR(bdev);
547 goto error;
548 }
549
550 ret = set_blocksize(bdev, 4096);
551 if (ret)
552 goto error_close;
a512bbf8 553 bh = btrfs_read_dev_super(bdev);
8a4b83cc
CM		 554 if (!bh) {
555 ret = -EIO;
556 goto error_close;
557 }
558 disk_super = (struct btrfs_super_block *)bh->b_data;
8a4b83cc 559 devid = le64_to_cpu(disk_super->dev_item.devid);
f2984462 560 transid = btrfs_super_generation(disk_super);
7ae9c09d 561 if (disk_super->label[0])
d397712b 562 printk(KERN_INFO "device label %s ", disk_super->label);
7ae9c09d
CM		 563 else {
564 /* FIXME, make a readl uuid parser */
d397712b 565 printk(KERN_INFO "device fsid %llx-%llx ",
7ae9c09d
CM		 566 *(unsigned long long *)disk_super->fsid,
567 *(unsigned long long *)(disk_super->fsid + 8));
568 }
119e10cf 569 printk(KERN_CONT "devid %llu transid %llu %s\n",
d397712b 570 (unsigned long long)devid, (unsigned long long)transid, path);
8a4b83cc
CM		 571 ret = device_list_add(path, disk_super, devid, fs_devices_ret);
572
8a4b83cc
CM		 573 brelse(bh);
574error_close:
15916de8 575 close_bdev_exclusive(bdev, flags);
8a4b83cc
CM		 576error:
577 mutex_unlock(&uuid_mutex);
578 return ret;
579}
0b86a832
CM		 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 */
a1b32a59
CM		 586static noinline int find_free_dev_extent(struct btrfs_trans_handle *trans,
587 struct btrfs_device *device,
a1b32a59 588 u64 num_bytes, u64 *start)
0b86a832
CM		 589{
590 struct btrfs_key key;
591 struct btrfs_root *root = device->dev_root;
592 struct btrfs_dev_extent *dev_extent = NULL;
2b82032c 593 struct btrfs_path *path;
0b86a832
CM		 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
2b82032c
YZ		 603 path = btrfs_alloc_path();
604 if (!path)
605 return -ENOMEM;
0b86a832 606 path->reada = 2;
2b82032c 607 start_found = 0;
0b86a832
CM		 608
609 /* FIXME use last free of some kind */
610
8a4b83cc
CM		 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);
8f18cf13
CM		 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
0b86a832
CM		 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;
639no_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 }
d397712b 676 if (btrfs_key_type(&key) != BTRFS_DEV_EXTENT_KEY)
0b86a832 677 goto next;
0b86a832
CM		 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);
682next:
683 path->slots[0]++;
684 cond_resched();
685 }
686check_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 */
0b86a832
CM		 690 BUG_ON(*start < search_start);
691
6324fbf3 692 if (*start + num_bytes > search_end) {
0b86a832
CM		 693 ret = -ENOSPC;
694 goto error;
695 }
696 /* check for pending inserts here */
2b82032c 697 ret = 0;
0b86a832
CM		 698
699error:
2b82032c 700 btrfs_free_path(path);
0b86a832
CM		 701 return ret;
702}
703
b2950863 704static int btrfs_free_dev_extent(struct btrfs_trans_handle *trans,
8f18cf13
CM		 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;
a061fc8d
CM		 712 struct btrfs_key found_key;
713 struct extent_buffer *leaf = NULL;
714 struct btrfs_dev_extent *extent = NULL;
8f18cf13
CM		 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);
a061fc8d
CM		 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 }
8f18cf13
CM		 741 BUG_ON(ret);
742
dfe25020
CM		 743 if (device->bytes_used > 0)
744 device->bytes_used -= btrfs_dev_extent_length(leaf, extent);
8f18cf13
CM		 745 ret = btrfs_del_item(trans, root, path);
746 BUG_ON(ret);
747
748 btrfs_free_path(path);
749 return ret;
750}
751
2b82032c 752int btrfs_alloc_dev_extent(struct btrfs_trans_handle *trans,
0b86a832 753 struct btrfs_device *device,
e17cade2 754 u64 chunk_tree, u64 chunk_objectid,
2b82032c 755 u64 chunk_offset, u64 start, u64 num_bytes)
0b86a832
CM		 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
dfe25020 764 WARN_ON(!device->in_fs_metadata);
0b86a832
CM		 765 path = btrfs_alloc_path();
766 if (!path)
767 return -ENOMEM;
768
0b86a832 769 key.objectid = device->devid;
2b82032c 770 key.offset = start;
0b86a832
CM		 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);
e17cade2
CM		 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
0b86a832
CM		 787 btrfs_set_dev_extent_length(leaf, extent, num_bytes);
788 btrfs_mark_buffer_dirty(leaf);
0b86a832
CM		 789 btrfs_free_path(path);
790 return ret;
791}
792
a1b32a59
CM		 793static noinline int find_next_chunk(struct btrfs_root *root,
794 u64 objectid, u64 *offset)
0b86a832
CM		 795{
796 struct btrfs_path *path;
797 int ret;
798 struct btrfs_key key;
e17cade2 799 struct btrfs_chunk *chunk;
0b86a832
CM		 800 struct btrfs_key found_key;
801
802 path = btrfs_alloc_path();
803 BUG_ON(!path);
804
e17cade2 805 key.objectid = objectid;
0b86a832
CM		 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) {
e17cade2 817 *offset = 0;
0b86a832
CM		 818 } else {
819 btrfs_item_key_to_cpu(path->nodes[0], &found_key,
820 path->slots[0]);
e17cade2
CM		 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 }
0b86a832
CM		 829 }
830 ret = 0;
831error:
832 btrfs_free_path(path);
833 return ret;
834}
835
2b82032c 836static noinline int find_next_devid(struct btrfs_root *root, u64 *objectid)
0b86a832
CM		 837{
838 int ret;
839 struct btrfs_key key;
840 struct btrfs_key found_key;
2b82032c
YZ		 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;
0b86a832
CM		 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;
869error:
2b82032c 870 btrfs_free_path(path);
0b86a832
CM		 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 */
878int 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;
0b86a832
CM		 888
889 root = root->fs_info->chunk_root;
890
891 path = btrfs_alloc_path();
892 if (!path)
893 return -ENOMEM;
894
0b86a832
CM		 895 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
896 key.type = BTRFS_DEV_ITEM_KEY;
2b82032c 897 key.offset = device->devid;
0b86a832
CM		 898
899 ret = btrfs_insert_empty_item(trans, root, path, &key,
0d81ba5d 900 sizeof(*dev_item));
0b86a832
CM		 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);
2b82032c 908 btrfs_set_device_generation(leaf, dev_item, 0);
0b86a832
CM		 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);
0b86a832
CM		 913 btrfs_set_device_total_bytes(leaf, dev_item, device->total_bytes);
914 btrfs_set_device_bytes_used(leaf, dev_item, device->bytes_used);
e17cade2
CM		 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);
c3027eb5 918 btrfs_set_device_start_offset(leaf, dev_item, 0);
0b86a832 919
0b86a832 920 ptr = (unsigned long)btrfs_device_uuid(dev_item);
e17cade2 921 write_extent_buffer(leaf, device->uuid, ptr, BTRFS_UUID_SIZE);
2b82032c
YZ		 922 ptr = (unsigned long)btrfs_device_fsid(dev_item);
923 write_extent_buffer(leaf, root->fs_info->fsid, ptr, BTRFS_UUID_SIZE);
0b86a832 924 btrfs_mark_buffer_dirty(leaf);
0b86a832 925
2b82032c 926 ret = 0;
0b86a832
CM		 927out:
928 btrfs_free_path(path);
929 return ret;
930}
8f18cf13 931
a061fc8d
CM		 932static int btrfs_rm_dev_item(struct btrfs_root *root,
933 struct btrfs_device *device)
934{
935 int ret;
936 struct btrfs_path *path;
a061fc8d 937 struct btrfs_key key;
a061fc8d
CM		 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;
7d9eb12c 950 lock_chunks(root);
a061fc8d
CM		 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;
a061fc8d
CM		 964out:
965 btrfs_free_path(path);
7d9eb12c 966 unlock_chunks(root);
a061fc8d
CM		 967 btrfs_commit_transaction(trans, root);
968 return ret;
969}
970
971int btrfs_rm_device(struct btrfs_root *root, char *device_path)
972{
973 struct btrfs_device *device;
2b82032c 974 struct btrfs_device *next_device;
a061fc8d 975 struct block_device *bdev;
dfe25020 976 struct buffer_head *bh = NULL;
a061fc8d
CM		 977 struct btrfs_super_block *disk_super;
978 u64 all_avail;
979 u64 devid;
2b82032c
YZ		 980 u64 num_devices;
981 u8 *dev_uuid;
a061fc8d
CM		 982 int ret = 0;
983
a061fc8d 984 mutex_lock(&uuid_mutex);
7d9eb12c 985 mutex_lock(&root->fs_info->volume_mutex);
a061fc8d
CM		 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) &&
2b82032c 992 root->fs_info->fs_devices->rw_devices <= 4) {
d397712b
CM		 993 printk(KERN_ERR "btrfs: unable to go below four devices "
994 "on raid10\n");
a061fc8d
CM		 995 ret = -EINVAL;
996 goto out;
997 }
998
999 if ((all_avail & BTRFS_BLOCK_GROUP_RAID1) &&
2b82032c 1000 root->fs_info->fs_devices->rw_devices <= 2) {
d397712b
CM		 1001 printk(KERN_ERR "btrfs: unable to go below two "
1002 "devices on raid1\n");
a061fc8d
CM		 1003 ret = -EINVAL;
1004 goto out;
1005 }
1006
dfe25020 1007 if (strcmp(device_path, "missing") == 0) {
dfe25020
CM		 1008 struct list_head *devices;
1009 struct btrfs_device *tmp;
a061fc8d 1010
dfe25020
CM		 1011 device = NULL;
1012 devices = &root->fs_info->fs_devices->devices;
c6e30871 1013 list_for_each_entry(tmp, devices, dev_list) {
dfe25020
CM		 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) {
d397712b
CM		 1023 printk(KERN_ERR "btrfs: no missing devices found to "
1024 "remove\n");
dfe25020
CM		 1025 goto out;
1026 }
dfe25020 1027 } else {
97288f2c 1028 bdev = open_bdev_exclusive(device_path, FMODE_READ,
dfe25020
CM		 1029 root->fs_info->bdev_holder);
1030 if (IS_ERR(bdev)) {
1031 ret = PTR_ERR(bdev);
1032 goto out;
1033 }
a061fc8d 1034
2b82032c 1035 set_blocksize(bdev, 4096);
a512bbf8 1036 bh = btrfs_read_dev_super(bdev);
dfe25020
CM		 1037 if (!bh) {
1038 ret = -EIO;
1039 goto error_close;
1040 }
1041 disk_super = (struct btrfs_super_block *)bh->b_data;
dfe25020 1042 devid = le64_to_cpu(disk_super->dev_item.devid);
2b82032c
YZ		 1043 dev_uuid = disk_super->dev_item.uuid;
1044 device = btrfs_find_device(root, devid, dev_uuid,
1045 disk_super->fsid);
dfe25020
CM		 1046 if (!device) {
1047 ret = -ENOENT;
1048 goto error_brelse;
1049 }
2b82032c 1050 }
dfe25020 1051
2b82032c 1052 if (device->writeable && root->fs_info->fs_devices->rw_devices == 1) {
d397712b
CM		 1053 printk(KERN_ERR "btrfs: unable to remove the only writeable "
1054 "device\n");
2b82032c
YZ		 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--;
dfe25020 1062 }
a061fc8d
CM		 1063
1064 ret = btrfs_shrink_device(device, 0);
1065 if (ret)
1066 goto error_brelse;
1067
a061fc8d
CM		 1068 ret = btrfs_rm_dev_item(root->fs_info->chunk_root, device);
1069 if (ret)
1070 goto error_brelse;
1071
2b82032c 1072 device->in_fs_metadata = 0;
e4404d6e
YZ		 1073 list_del_init(&device->dev_list);
1074 device->fs_devices->num_devices--;
2b82032c
YZ		 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
e4404d6e
YZ		 1083 if (device->bdev) {
1084 close_bdev_exclusive(device->bdev, device->mode);
1085 device->bdev = NULL;
1086 device->fs_devices->open_devices--;
1087 }
1088
2b82032c
YZ		 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
e4404d6e
YZ		 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;
2b82032c 1099 }
e4404d6e
YZ		 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);
2b82032c
YZ		 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) {
dfe25020
CM		 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);
dfe25020 1117 }
a061fc8d
CM		 1118
1119 kfree(device->name);
1120 kfree(device);
1121 ret = 0;
a061fc8d
CM		 1122
1123error_brelse:
1124 brelse(bh);
1125error_close:
dfe25020 1126 if (bdev)
97288f2c 1127 close_bdev_exclusive(bdev, FMODE_READ);
a061fc8d 1128out:
7d9eb12c 1129 mutex_unlock(&root->fs_info->volume_mutex);
a061fc8d 1130 mutex_unlock(&uuid_mutex);
a061fc8d
CM		 1131 return ret;
1132}
1133
2b82032c
YZ		 1134/*
1135 * does all the dirty work required for changing file system's UUID.
1136 */
1137static 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;
e4404d6e 1142 struct btrfs_fs_devices *seed_devices;
2b82032c
YZ		 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));
e4404d6e 1148 if (!fs_devices->seeding)
2b82032c
YZ		 1149 return -EINVAL;
1150
e4404d6e
YZ		 1151 seed_devices = kzalloc(sizeof(*fs_devices), GFP_NOFS);
1152 if (!seed_devices)
2b82032c
YZ		 1153 return -ENOMEM;
1154
e4404d6e
YZ		 1155 old_devices = clone_fs_devices(fs_devices);
1156 if (IS_ERR(old_devices)) {
1157 kfree(seed_devices);
1158 return PTR_ERR(old_devices);
2b82032c 1159 }
e4404d6e 1160
2b82032c
YZ		 1161 list_add(&old_devices->list, &fs_uuids);
1162
e4404d6e
YZ		 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
2b82032c
YZ		 1173 fs_devices->seeding = 0;
1174 fs_devices->num_devices = 0;
1175 fs_devices->open_devices = 0;
e4404d6e 1176 fs_devices->seed = seed_devices;
2b82032c
YZ		 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 */
1191static 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];
1219next_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;
1259error:
1260 btrfs_free_path(path);
1261 return ret;
1262}
1263
788f20eb
CM		 1264int 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;
788f20eb 1269 struct list_head *devices;
2b82032c 1270 struct super_block *sb = root->fs_info->sb;
788f20eb 1271 u64 total_bytes;
2b82032c 1272 int seeding_dev = 0;
788f20eb
CM		 1273 int ret = 0;
1274
2b82032c
YZ		 1275 if ((sb->s_flags & MS_RDONLY) && !root->fs_info->fs_devices->seeding)
1276 return -EINVAL;
788f20eb 1277
15916de8 1278 bdev = open_bdev_exclusive(device_path, 0, root->fs_info->bdev_holder);
d397712b 1279 if (!bdev)
788f20eb 1280 return -EIO;
a2135011 1281
2b82032c
YZ		 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
8c8bee1d 1288 filemap_write_and_wait(bdev->bd_inode->i_mapping);
7d9eb12c 1289 mutex_lock(&root->fs_info->volume_mutex);
a2135011 1290
788f20eb 1291 devices = &root->fs_info->fs_devices->devices;
c6e30871 1292 list_for_each_entry(device, devices, dev_list) {
788f20eb
CM		 1293 if (device->bdev == bdev) {
1294 ret = -EEXIST;
2b82032c 1295 goto error;
788f20eb
CM		 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;
2b82032c 1303 goto error;
788f20eb
CM		 1304 }
1305
788f20eb
CM		 1306 device->name = kstrdup(device_path, GFP_NOFS);
1307 if (!device->name) {
1308 kfree(device);
2b82032c
YZ		 1309 ret = -ENOMEM;
1310 goto error;
788f20eb 1311 }
2b82032c
YZ		 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;
788f20eb
CM		 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;
dfe25020 1334 device->in_fs_metadata = 1;
15916de8 1335 device->mode = 0;
2b82032c 1336 set_blocksize(device->bdev, 4096);
788f20eb 1337
2b82032c
YZ		 1338 if (seeding_dev) {
1339 sb->s_flags &= ~MS_RDONLY;
1340 ret = btrfs_prepare_sprout(trans, root);
1341 BUG_ON(ret);
1342 }
788f20eb 1343
2b82032c
YZ		 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;
325cd4ba 1352
788f20eb
CM		 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
2b82032c
YZ		 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
7d9eb12c 1370 unlock_chunks(root);
2b82032c 1371 btrfs_commit_transaction(trans, root);
a2135011 1372
2b82032c
YZ		 1373 if (seeding_dev) {
1374 mutex_unlock(&uuid_mutex);
1375 up_write(&sb->s_umount);
788f20eb 1376
2b82032c
YZ		 1377 ret = btrfs_relocate_sys_chunks(root);
1378 BUG_ON(ret);
1379 }
1380out:
1381 mutex_unlock(&root->fs_info->volume_mutex);
1382 return ret;
1383error:
15916de8 1384 close_bdev_exclusive(bdev, 0);
2b82032c
YZ		 1385 if (seeding_dev) {
1386 mutex_unlock(&uuid_mutex);
1387 up_write(&sb->s_umount);
1388 }
788f20eb
CM		 1389 goto out;
1390}
1391
d397712b
CM		 1392static noinline int btrfs_update_device(struct btrfs_trans_handle *trans,
1393 struct btrfs_device *device)
0b86a832
CM		 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);
0b86a832
CM		 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
1433out:
1434 btrfs_free_path(path);
1435 return ret;
1436}
1437
7d9eb12c 1438static int __btrfs_grow_device(struct btrfs_trans_handle *trans,
8f18cf13
CM		 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
2b82032c
YZ		 1446 if (!device->writeable)
1447 return -EACCES;
1448 if (new_size <= device->total_bytes)
1449 return -EINVAL;
1450
8f18cf13 1451 btrfs_set_super_total_bytes(super_copy, old_total + diff);
2b82032c
YZ		 1452 device->fs_devices->total_rw_bytes += diff;
1453
1454 device->total_bytes = new_size;
8f18cf13
CM		 1455 return btrfs_update_device(trans, device);
1456}
1457
7d9eb12c
CM		 1458int 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
8f18cf13
CM		 1468static 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
b2950863 1496static int btrfs_del_sys_chunk(struct btrfs_root *root, u64 chunk_objectid, u64
8f18cf13
CM		 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
b2950863 1542static int btrfs_relocate_chunk(struct btrfs_root *root,
8f18cf13
CM		 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
d397712b 1554 printk(KERN_INFO "btrfs relocating chunk %llu\n",
323da79c 1555 (unsigned long long)chunk_offset);
8f18cf13
CM		 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 */
1a40e23b 1561 ret = btrfs_relocate_block_group(extent_root, chunk_offset);
8f18cf13
CM		 1562 BUG_ON(ret);
1563
1564 trans = btrfs_start_transaction(root, 1);
1565 BUG_ON(!trans);
1566
7d9eb12c
CM		 1567 lock_chunks(root);
1568
8f18cf13
CM		 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
a061fc8d
CM		 1577 BUG_ON(em->start > chunk_offset ||
1578 em->start + em->len < chunk_offset);
8f18cf13
CM		 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);
a061fc8d 1585
dfe25020
CM		 1586 if (map->stripes[i].dev) {
1587 ret = btrfs_update_device(trans, map->stripes[i].dev);
1588 BUG_ON(ret);
1589 }
8f18cf13
CM		 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);
8f18cf13
CM		 1599 }
1600
2b82032c
YZ		 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
1621static 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;
1a40e23b 1653
2b82032c
YZ		 1654 leaf = path->nodes[0];
1655 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
1a40e23b 1656
2b82032c
YZ		 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);
8f18cf13 1661
2b82032c
YZ		 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 }
8f18cf13 1668
2b82032c
YZ		 1669 if (found_key.offset == 0)
1670 break;
1671 key.offset = found_key.offset - 1;
1672 }
1673 ret = 0;
1674error:
1675 btrfs_free_path(path);
1676 return ret;
8f18cf13
CM		 1677}
1678
ec44a35c
CM		 1679static 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
ec44a35c
CM		 1688int btrfs_balance(struct btrfs_root *dev_root)
1689{
1690 int ret;
ec44a35c
CM		 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
2b82032c
YZ		 1702 if (dev_root->fs_info->sb->s_flags & MS_RDONLY)
1703 return -EROFS;
ec44a35c 1704
7d9eb12c 1705 mutex_lock(&dev_root->fs_info->volume_mutex);
ec44a35c
CM		 1706 dev_root = dev_root->fs_info->dev_root;
1707
ec44a35c 1708 /* step one make some room on all the devices */
c6e30871 1709 list_for_each_entry(device, devices, dev_list) {
ec44a35c
CM		 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);
2b82032c
YZ		 1713 if (!device->writeable ||
1714 device->total_bytes - device->bytes_used > size_to_free)
ec44a35c
CM		 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
d397712b 1737 while (1) {
ec44a35c
CM		 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);
7d9eb12c 1751 if (ret)
ec44a35c 1752 break;
7d9eb12c 1753
ec44a35c
CM		 1754 btrfs_item_key_to_cpu(path->nodes[0], &found_key,
1755 path->slots[0]);
1756 if (found_key.objectid != key.objectid)
1757 break;
7d9eb12c 1758
ec44a35c
CM		 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
7d9eb12c 1767 btrfs_release_path(chunk_root, path);
ec44a35c
CM		 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);
ec44a35c
CM		 1773 }
1774 ret = 0;
1775error:
1776 btrfs_free_path(path);
7d9eb12c 1777 mutex_unlock(&dev_root->fs_info->volume_mutex);
ec44a35c
CM		 1778 return ret;
1779}
1780
8f18cf13
CM		 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 */
1786int 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
2b82032c
YZ		 1804 if (new_size >= device->total_bytes)
1805 return -EINVAL;
8f18cf13
CM		 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
7d9eb12c
CM		 1819 lock_chunks(root);
1820
8f18cf13 1821 device->total_bytes = new_size;
2b82032c
YZ		 1822 if (device->writeable)
1823 device->fs_devices->total_rw_bytes -= diff;
8f18cf13
CM		 1824 ret = btrfs_update_device(trans, device);
1825 if (ret) {
7d9eb12c 1826 unlock_chunks(root);
8f18cf13
CM		 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);
7d9eb12c 1832 unlock_chunks(root);
8f18cf13
CM		 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
1876done:
1877 btrfs_free_path(path);
1878 return ret;
1879}
1880
b2950863 1881static int btrfs_add_system_chunk(struct btrfs_trans_handle *trans,
0b86a832
CM		 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
d397712b 1905static noinline u64 chunk_bytes_by_type(u64 type, u64 calc_size,
a1b32a59 1906 int num_stripes, int sub_stripes)
9b3f68b9
CM		 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
2b82032c
YZ		 1916static 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)
0b86a832 1921{
593060d7 1922 struct btrfs_fs_info *info = extent_root->fs_info;
0b86a832 1923 struct btrfs_device *device = NULL;
2b82032c 1924 struct btrfs_fs_devices *fs_devices = info->fs_devices;
6324fbf3 1925 struct list_head *cur;
2b82032c 1926 struct map_lookup *map = NULL;
0b86a832 1927 struct extent_map_tree *em_tree;
0b86a832 1928 struct extent_map *em;
2b82032c 1929 struct list_head private_devs;
a40a90a0 1930 int min_stripe_size = 1 * 1024 * 1024;
0b86a832 1931 u64 calc_size = 1024 * 1024 * 1024;
9b3f68b9
CM		 1932 u64 max_chunk_size = calc_size;
1933 u64 min_free;
6324fbf3
CM		 1934 u64 avail;
1935 u64 max_avail = 0;
2b82032c 1936 u64 dev_offset;
6324fbf3 1937 int num_stripes = 1;
a40a90a0 1938 int min_stripes = 1;
321aecc6 1939 int sub_stripes = 0;
6324fbf3 1940 int looped = 0;
0b86a832 1941 int ret;
6324fbf3 1942 int index;
593060d7 1943 int stripe_len = 64 * 1024;
0b86a832 1944
ec44a35c
CM		 1945 if ((type & BTRFS_BLOCK_GROUP_RAID1) &&
1946 (type & BTRFS_BLOCK_GROUP_DUP)) {
1947 WARN_ON(1);
1948 type &= ~BTRFS_BLOCK_GROUP_DUP;
1949 }
2b82032c 1950 if (list_empty(&fs_devices->alloc_list))
6324fbf3 1951 return -ENOSPC;
593060d7 1952
a40a90a0 1953 if (type & (BTRFS_BLOCK_GROUP_RAID0)) {
2b82032c 1954 num_stripes = fs_devices->rw_devices;
a40a90a0
CM		 1955 min_stripes = 2;
1956 }
1957 if (type & (BTRFS_BLOCK_GROUP_DUP)) {
611f0e00 1958 num_stripes = 2;
a40a90a0
CM		 1959 min_stripes = 2;
1960 }
8790d502 1961 if (type & (BTRFS_BLOCK_GROUP_RAID1)) {
2b82032c 1962 num_stripes = min_t(u64, 2, fs_devices->rw_devices);
9b3f68b9
CM		 1963 if (num_stripes < 2)
1964 return -ENOSPC;
a40a90a0 1965 min_stripes = 2;
8790d502 1966 }
321aecc6 1967 if (type & (BTRFS_BLOCK_GROUP_RAID10)) {
2b82032c 1968 num_stripes = fs_devices->rw_devices;
321aecc6
CM		 1969 if (num_stripes < 4)
1970 return -ENOSPC;
1971 num_stripes &= ~(u32)1;
1972 sub_stripes = 2;
a40a90a0 1973 min_stripes = 4;
321aecc6 1974 }
9b3f68b9
CM		 1975
1976 if (type & BTRFS_BLOCK_GROUP_DATA) {
1977 max_chunk_size = 10 * calc_size;
a40a90a0 1978 min_stripe_size = 64 * 1024 * 1024;
9b3f68b9
CM		 1979 } else if (type & BTRFS_BLOCK_GROUP_METADATA) {
1980 max_chunk_size = 4 * calc_size;
a40a90a0
CM		 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;
9b3f68b9
CM		 1986 }
1987
2b82032c
YZ		 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);
9b3f68b9 1991
a40a90a0 1992again:
2b82032c
YZ		 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
9b3f68b9
CM		 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 */
a40a90a0 2008 calc_size = max_t(u64, min_stripe_size, calc_size);
9b3f68b9 2009
9b3f68b9
CM		 2010 do_div(calc_size, stripe_len);
2011 calc_size *= stripe_len;
2012
2b82032c 2013 cur = fs_devices->alloc_list.next;
6324fbf3 2014 index = 0;
611f0e00
CM		 2015
2016 if (type & BTRFS_BLOCK_GROUP_DUP)
2017 min_free = calc_size * 2;
9b3f68b9
CM		 2018 else
2019 min_free = calc_size;
611f0e00 2020
0f9dd46c
JB		 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;
ad5bd91e 2028
2b82032c 2029 INIT_LIST_HEAD(&private_devs);
d397712b 2030 while (index < num_stripes) {
b3075717 2031 device = list_entry(cur, struct btrfs_device, dev_alloc_list);
2b82032c 2032 BUG_ON(!device->writeable);
dfe25020
CM		 2033 if (device->total_bytes > device->bytes_used)
2034 avail = device->total_bytes - device->bytes_used;
2035 else
2036 avail = 0;
6324fbf3 2037 cur = cur->next;
8f18cf13 2038
dfe25020 2039 if (device->in_fs_metadata && avail >= min_free) {
2b82032c
YZ		 2040 ret = find_free_dev_extent(trans, device,
2041 min_free, &dev_offset);
8f18cf13
CM		 2042 if (ret == 0) {
2043 list_move_tail(&device->dev_alloc_list,
2044 &private_devs);
2b82032c
YZ		 2045 map->stripes[index].dev = device;
2046 map->stripes[index].physical = dev_offset;
611f0e00 2047 index++;
2b82032c
YZ		 2048 if (type & BTRFS_BLOCK_GROUP_DUP) {
2049 map->stripes[index].dev = device;
2050 map->stripes[index].physical =
2051 dev_offset + calc_size;
8f18cf13 2052 index++;
2b82032c 2053 }
8f18cf13 2054 }
dfe25020 2055 } else if (device->in_fs_metadata && avail > max_avail)
a40a90a0 2056 max_avail = avail;
2b82032c 2057 if (cur == &fs_devices->alloc_list)
6324fbf3
CM		 2058 break;
2059 }
2b82032c 2060 list_splice(&private_devs, &fs_devices->alloc_list);
6324fbf3 2061 if (index < num_stripes) {
a40a90a0
CM		 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 }
6324fbf3
CM		 2071 if (!looped && max_avail > 0) {
2072 looped = 1;
2073 calc_size = max_avail;
2074 goto again;
2075 }
2b82032c 2076 kfree(map);
6324fbf3
CM		 2077 return -ENOSPC;
2078 }
2b82032c
YZ		 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;
0b86a832 2086
2b82032c
YZ		 2087 *map_ret = map;
2088 *stripe_size = calc_size;
2089 *num_bytes = chunk_bytes_by_type(type, calc_size,
2090 num_stripes, sub_stripes);
0b86a832 2091
2b82032c
YZ		 2092 em = alloc_extent_map(GFP_NOFS);
2093 if (!em) {
2094 kfree(map);
593060d7
CM		 2095 return -ENOMEM;
2096 }
2b82032c
YZ		 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;
593060d7 2102
2b82032c
YZ		 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);
0b86a832 2109
2b82032c
YZ		 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);
611f0e00 2114
2b82032c
YZ		 2115 index = 0;
2116 while (index < map->num_stripes) {
2117 device = map->stripes[index].dev;
2118 dev_offset = map->stripes[index].physical;
0b86a832
CM		 2119
2120 ret = btrfs_alloc_dev_extent(trans, device,
2b82032c
YZ		 2121 info->chunk_root->root_key.objectid,
2122 BTRFS_FIRST_CHUNK_TREE_OBJECTID,
2123 start, dev_offset, calc_size);
0b86a832 2124 BUG_ON(ret);
2b82032c
YZ		 2125 index++;
2126 }
2127
2128 return 0;
2129}
2130
2131static 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;
0b86a832
CM		 2154 ret = btrfs_update_device(trans, device);
2155 BUG_ON(ret);
2b82032c
YZ		 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;
0b86a832 2164
e17cade2
CM		 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);
2b82032c 2168 stripe++;
0b86a832
CM		 2169 index++;
2170 }
2171
2b82032c 2172 btrfs_set_stack_chunk_length(chunk, chunk_size);
0b86a832 2173 btrfs_set_stack_chunk_owner(chunk, extent_root->root_key.objectid);
2b82032c
YZ		 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);
0b86a832 2179 btrfs_set_stack_chunk_sector_size(chunk, extent_root->sectorsize);
2b82032c 2180 btrfs_set_stack_chunk_sub_stripes(chunk, map->sub_stripes);
0b86a832 2181
2b82032c
YZ		 2182 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
2183 key.type = BTRFS_CHUNK_ITEM_KEY;
2184 key.offset = chunk_offset;
0b86a832 2185
2b82032c
YZ		 2186 ret = btrfs_insert_item(trans, chunk_root, &key, chunk, item_size);
2187 BUG_ON(ret);
0b86a832 2188
2b82032c
YZ		 2189 if (map->type & BTRFS_BLOCK_GROUP_SYSTEM) {
2190 ret = btrfs_add_system_chunk(trans, chunk_root, &key, chunk,
2191 item_size);
8f18cf13
CM		 2192 BUG_ON(ret);
2193 }
0b86a832 2194 kfree(chunk);
2b82032c
YZ		 2195 return 0;
2196}
0b86a832 2197
2b82032c
YZ		 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 */
2205int 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
d397712b 2231static noinline int init_first_rw_device(struct btrfs_trans_handle *trans,
2b82032c
YZ		 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);
b248a415 2289 BUG_ON(ret);
2b82032c
YZ		 2290 return 0;
2291}
2292
2293int 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 }
0b86a832 2314 free_extent_map(em);
2b82032c 2315 return readonly;
0b86a832
CM		 2316}
2317
2318void btrfs_mapping_init(struct btrfs_mapping_tree *tree)
2319{
2320 extent_map_tree_init(&tree->map_tree, GFP_NOFS);
2321}
2322
2323void btrfs_mapping_tree_free(struct btrfs_mapping_tree *tree)
2324{
2325 struct extent_map *em;
2326
d397712b 2327 while (1) {
0b86a832
CM		 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
f188591e
CM		 2343int 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);
b248a415 2352 spin_unlock(&em_tree->lock);
f188591e
CM		 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;
321aecc6
CM		 2359 else if (map->type & BTRFS_BLOCK_GROUP_RAID10)
2360 ret = map->sub_stripes;
f188591e
CM		 2361 else
2362 ret = 1;
2363 free_extent_map(em);
f188591e
CM		 2364 return ret;
2365}
2366
dfe25020
CM		 2367static 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
f2d8d74d
CM		 2383static 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)
0b86a832
CM		 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;
593060d7
CM		 2392 u64 stripe_offset;
2393 u64 stripe_nr;
cea9e445 2394 int stripes_allocated = 8;
321aecc6 2395 int stripes_required = 1;
593060d7 2396 int stripe_index;
cea9e445 2397 int i;
f2d8d74d 2398 int num_stripes;
a236aed1 2399 int max_errors = 0;
cea9e445 2400 struct btrfs_multi_bio *multi = NULL;
0b86a832 2401
d397712b 2402 if (multi_ret && !(rw & (1 << BIO_RW)))
cea9e445 2403 stripes_allocated = 1;
cea9e445
CM		 2404again:
2405 if (multi_ret) {
2406 multi = kzalloc(btrfs_multi_bio_size(stripes_allocated),
2407 GFP_NOFS);
2408 if (!multi)
2409 return -ENOMEM;
a236aed1
CM		 2410
2411 atomic_set(&multi->error, 0);
cea9e445 2412 }
0b86a832
CM		 2413
2414 spin_lock(&em_tree->lock);
2415 em = lookup_extent_mapping(em_tree, logical, *length);
b248a415 2416 spin_unlock(&em_tree->lock);
f2d8d74d
CM		 2417
2418 if (!em && unplug_page)
2419 return 0;
2420
3b951516 2421 if (!em) {
d397712b
CM		 2422 printk(KERN_CRIT "unable to find logical %llu len %llu\n",
2423 (unsigned long long)logical,
2424 (unsigned long long)*length);
f2d8d74d 2425 BUG();
3b951516 2426 }
0b86a832
CM		 2427
2428 BUG_ON(em->start > logical || em->start + em->len < logical);
2429 map = (struct map_lookup *)em->bdev;
2430 offset = logical - em->start;
593060d7 2431
f188591e
CM		 2432 if (mirror_num > map->num_stripes)
2433 mirror_num = 0;
2434
cea9e445 2435 /* if our multi bio struct is too small, back off and try again */
321aecc6
CM		 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;
a236aed1 2440 max_errors = 1;
321aecc6
CM		 2441 } else if (map->type & BTRFS_BLOCK_GROUP_RAID10) {
2442 stripes_required = map->sub_stripes;
a236aed1 2443 max_errors = 1;
321aecc6
CM		 2444 }
2445 }
2446 if (multi_ret && rw == WRITE &&
2447 stripes_allocated < stripes_required) {
cea9e445 2448 stripes_allocated = map->num_stripes;
cea9e445
CM		 2449 free_extent_map(em);
2450 kfree(multi);
2451 goto again;
2452 }
593060d7
CM		 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
cea9e445 2466 if (map->type & (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID1 |
321aecc6 2467 BTRFS_BLOCK_GROUP_RAID10 |
cea9e445
CM		 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 }
f2d8d74d
CM		 2475
2476 if (!multi_ret && !unplug_page)
cea9e445
CM		 2477 goto out;
2478
f2d8d74d 2479 num_stripes = 1;
cea9e445 2480 stripe_index = 0;
8790d502 2481 if (map->type & BTRFS_BLOCK_GROUP_RAID1) {
f2d8d74d
CM		 2482 if (unplug_page || (rw & (1 << BIO_RW)))
2483 num_stripes = map->num_stripes;
2fff734f 2484 else if (mirror_num)
f188591e 2485 stripe_index = mirror_num - 1;
dfe25020
CM		 2486 else {
2487 stripe_index = find_live_mirror(map, 0,
2488 map->num_stripes,
2489 current->pid % map->num_stripes);
2490 }
2fff734f 2491
611f0e00 2492 } else if (map->type & BTRFS_BLOCK_GROUP_DUP) {
cea9e445 2493 if (rw & (1 << BIO_RW))
f2d8d74d 2494 num_stripes = map->num_stripes;
f188591e
CM		 2495 else if (mirror_num)
2496 stripe_index = mirror_num - 1;
2fff734f 2497
321aecc6
CM		 2498 } else if (map->type & BTRFS_BLOCK_GROUP_RAID10) {
2499 int factor = map->num_stripes / map->sub_stripes;
321aecc6
CM		 2500
2501 stripe_index = do_div(stripe_nr, factor);
2502 stripe_index *= map->sub_stripes;
2503
f2d8d74d
CM		 2504 if (unplug_page || (rw & (1 << BIO_RW)))
2505 num_stripes = map->sub_stripes;
321aecc6
CM		 2506 else if (mirror_num)
2507 stripe_index += mirror_num - 1;
dfe25020
CM		 2508 else {
2509 stripe_index = find_live_mirror(map, stripe_index,
2510 map->sub_stripes, stripe_index +
2511 current->pid % map->sub_stripes);
2512 }
8790d502
CM		 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 }
593060d7 2521 BUG_ON(stripe_index >= map->num_stripes);
cea9e445 2522
f2d8d74d
CM		 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;
dfe25020
CM		 2529 if (device->bdev) {
2530 bdi = blk_get_backing_dev_info(device->bdev);
d397712b 2531 if (bdi->unplug_io_fn)
dfe25020 2532 bdi->unplug_io_fn(bdi, unplug_page);
f2d8d74d
CM		 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 }
cea9e445 2540 stripe_index++;
593060d7 2541 }
f2d8d74d
CM		 2542 if (multi_ret) {
2543 *multi_ret = multi;
2544 multi->num_stripes = num_stripes;
a236aed1 2545 multi->max_errors = max_errors;
f2d8d74d 2546 }
cea9e445 2547out:
0b86a832 2548 free_extent_map(em);
0b86a832
CM		 2549 return 0;
2550}
2551
f2d8d74d
CM		 2552int 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
a512bbf8
YZ		 2560int 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;
934d375b 2606 WARN_ON(nr >= map->num_stripes);
a512bbf8
YZ		 2607 for (j = 0; j < nr; j++) {
2608 if (buf[j] == bytenr)
2609 break;
2610 }
934d375b
CM		 2611 if (j == nr) {
2612 WARN_ON(nr >= map->num_stripes);
a512bbf8 2613 buf[nr++] = bytenr;
934d375b 2614 }
a512bbf8
YZ		 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
f2d8d74d
CM		 2645int 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
8790d502 2653static void end_bio_multi_stripe(struct bio *bio, int err)
8790d502 2654{
cea9e445 2655 struct btrfs_multi_bio *multi = bio->bi_private;
7d2b4daa 2656 int is_orig_bio = 0;
8790d502 2657
8790d502 2658 if (err)
a236aed1 2659 atomic_inc(&multi->error);
8790d502 2660
7d2b4daa
CM		 2661 if (bio == multi->orig_bio)
2662 is_orig_bio = 1;
2663
cea9e445 2664 if (atomic_dec_and_test(&multi->stripes_pending)) {
7d2b4daa
CM		 2665 if (!is_orig_bio) {
2666 bio_put(bio);
2667 bio = multi->orig_bio;
2668 }
8790d502
CM		 2669 bio->bi_private = multi->private;
2670 bio->bi_end_io = multi->end_io;
a236aed1
CM		 2671 /* only send an error to the higher layers if it is
2672 * beyond the tolerance of the multi-bio
2673 */
1259ab75 2674 if (atomic_read(&multi->error) > multi->max_errors) {
a236aed1 2675 err = -EIO;
1259ab75
CM		 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);
a236aed1 2682 err = 0;
1259ab75 2683 }
8790d502
CM		 2684 kfree(multi);
2685
2686 bio_endio(bio, err);
7d2b4daa 2687 } else if (!is_orig_bio) {
8790d502
CM		 2688 bio_put(bio);
2689 }
8790d502
CM		 2690}
2691
8b712842
CM		 2692struct 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 */
d397712b 2706static noinline int schedule_bio(struct btrfs_root *root,
a1b32a59
CM		 2707 struct btrfs_device *device,
2708 int rw, struct bio *bio)
8b712842
CM		 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))) {
492bb6de 2714 bio_get(bio);
8b712842 2715 submit_bio(rw, bio);
492bb6de 2716 bio_put(bio);
8b712842
CM		 2717 return 0;
2718 }
2719
2720 /*
0986fe9e 2721 * nr_async_bios allows us to reliably return congestion to the
8b712842
CM		 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 */
0986fe9e 2726 atomic_inc(&root->fs_info->nr_async_bios);
492bb6de 2727 WARN_ON(bio->bi_next);
8b712842
CM		 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)
1cc127b5
CM		 2745 btrfs_queue_worker(&root->fs_info->submit_workers,
2746 &device->work);
8b712842
CM		 2747 return 0;
2748}
2749
f188591e 2750int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio,
8b712842 2751 int mirror_num, int async_submit)
0b86a832
CM		 2752{
2753 struct btrfs_mapping_tree *map_tree;
2754 struct btrfs_device *dev;
8790d502 2755 struct bio *first_bio = bio;
a62b9401 2756 u64 logical = (u64)bio->bi_sector << 9;
0b86a832
CM		 2757 u64 length = 0;
2758 u64 map_length;
cea9e445 2759 struct btrfs_multi_bio *multi = NULL;
0b86a832 2760 int ret;
8790d502
CM		 2761 int dev_nr = 0;
2762 int total_devs = 1;
0b86a832 2763
f2d8d74d 2764 length = bio->bi_size;
0b86a832
CM		 2765 map_tree = &root->fs_info->mapping_tree;
2766 map_length = length;
cea9e445 2767
f188591e
CM		 2768 ret = btrfs_map_block(map_tree, rw, logical, &map_length, &multi,
2769 mirror_num);
cea9e445
CM		 2770 BUG_ON(ret);
2771
2772 total_devs = multi->num_stripes;
2773 if (map_length < length) {
d397712b
CM		 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);
cea9e445
CM		 2778 BUG();
2779 }
2780 multi->end_io = first_bio->bi_end_io;
2781 multi->private = first_bio->bi_private;
7d2b4daa 2782 multi->orig_bio = first_bio;
cea9e445
CM		 2783 atomic_set(&multi->stripes_pending, multi->num_stripes);
2784
d397712b 2785 while (dev_nr < total_devs) {
8790d502 2786 if (total_devs > 1) {
8790d502
CM		 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 }
cea9e445
CM		 2796 bio->bi_sector = multi->stripes[dev_nr].physical >> 9;
2797 dev = multi->stripes[dev_nr].dev;
2b82032c 2798 BUG_ON(rw == WRITE && !dev->writeable);
dfe25020
CM		 2799 if (dev && dev->bdev) {
2800 bio->bi_bdev = dev->bdev;
8b712842
CM		 2801 if (async_submit)
2802 schedule_bio(root, dev, rw, bio);
2803 else
2804 submit_bio(rw, bio);
dfe25020
CM		 2805 } else {
2806 bio->bi_bdev = root->fs_info->fs_devices->latest_bdev;
2807 bio->bi_sector = logical >> 9;
dfe25020 2808 bio_endio(bio, -EIO);
dfe25020 2809 }
8790d502
CM		 2810 dev_nr++;
2811 }
cea9e445
CM		 2812 if (total_devs == 1)
2813 kfree(multi);
0b86a832
CM		 2814 return 0;
2815}
2816
a443755f 2817struct btrfs_device *btrfs_find_device(struct btrfs_root *root, u64 devid,
2b82032c 2818 u8 *uuid, u8 *fsid)
0b86a832 2819{
2b82032c
YZ		 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;
0b86a832
CM		 2835}
2836
dfe25020
CM		 2837static 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);
7cbd8a83 2844 if (!device)
2845 return NULL;
dfe25020
CM		 2846 list_add(&device->dev_list,
2847 &fs_devices->devices);
dfe25020
CM		 2848 device->barriers = 1;
2849 device->dev_root = root->fs_info->dev_root;
2850 device->devid = devid;
8b712842 2851 device->work.func = pending_bios_fn;
e4404d6e 2852 device->fs_devices = fs_devices;
dfe25020
CM		 2853 fs_devices->num_devices++;
2854 spin_lock_init(&device->io_lock);
d20f7043 2855 INIT_LIST_HEAD(&device->dev_alloc_list);
dfe25020
CM		 2856 memcpy(device->uuid, dev_uuid, BTRFS_UUID_SIZE);
2857 return device;
2858}
2859
0b86a832
CM		 2860static 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;
a443755f 2870 u8 uuid[BTRFS_UUID_SIZE];
593060d7 2871 int num_stripes;
0b86a832 2872 int ret;
593060d7 2873 int i;
0b86a832 2874
e17cade2
CM		 2875 logical = key->offset;
2876 length = btrfs_chunk_length(leaf, chunk);
a061fc8d 2877
0b86a832
CM		 2878 spin_lock(&map_tree->map_tree.lock);
2879 em = lookup_extent_mapping(&map_tree->map_tree, logical, 1);
b248a415 2880 spin_unlock(&map_tree->map_tree.lock);
0b86a832
CM		 2881
2882 /* already mapped? */
2883 if (em && em->start <= logical && em->start + em->len > logical) {
2884 free_extent_map(em);
0b86a832
CM		 2885 return 0;
2886 } else if (em) {
2887 free_extent_map(em);
2888 }
0b86a832
CM		 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;
593060d7
CM		 2897 num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
2898 map = kmalloc(map_lookup_size(num_stripes), GFP_NOFS);
0b86a832
CM		 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;
c8b97818 2908 em->block_len = em->len;
0b86a832 2909
593060d7
CM		 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);
321aecc6 2916 map->sub_stripes = btrfs_chunk_sub_stripes(leaf, chunk);
593060d7
CM		 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);
a443755f
CM		 2921 read_extent_buffer(leaf, uuid, (unsigned long)
2922 btrfs_stripe_dev_uuid_nr(chunk, i),
2923 BTRFS_UUID_SIZE);
2b82032c
YZ		 2924 map->stripes[i].dev = btrfs_find_device(root, devid, uuid,
2925 NULL);
dfe25020 2926 if (!map->stripes[i].dev && !btrfs_test_opt(root, DEGRADED)) {
593060d7
CM		 2927 kfree(map);
2928 free_extent_map(em);
2929 return -EIO;
2930 }
dfe25020
CM		 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;
0b86a832
CM		 2941 }
2942
2943 spin_lock(&map_tree->map_tree.lock);
2944 ret = add_extent_mapping(&map_tree->map_tree, em);
0b86a832 2945 spin_unlock(&map_tree->map_tree.lock);
b248a415 2946 BUG_ON(ret);
0b86a832
CM		 2947 free_extent_map(em);
2948
2949 return 0;
2950}
2951
2952static 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;
0b86a832
CM		 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);
0b86a832
CM		 2965
2966 ptr = (unsigned long)btrfs_device_uuid(dev_item);
e17cade2 2967 read_extent_buffer(leaf, device->uuid, ptr, BTRFS_UUID_SIZE);
0b86a832 2968
0b86a832
CM		 2969 return 0;
2970}
2971
2b82032c
YZ		 2972static 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 }
e4404d6e
YZ		 2993
2994 fs_devices = clone_fs_devices(fs_devices);
2995 if (IS_ERR(fs_devices)) {
2996 ret = PTR_ERR(fs_devices);
2b82032c
YZ		 2997 goto out;
2998 }
2999
97288f2c 3000 ret = __btrfs_open_devices(fs_devices, FMODE_READ,
15916de8 3001 root->fs_info->bdev_holder);
2b82032c
YZ		 3002 if (ret)
3003 goto out;
3004
3005 if (!fs_devices->seeding) {
3006 __btrfs_close_devices(fs_devices);
e4404d6e 3007 free_fs_devices(fs_devices);
2b82032c
YZ		 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;
2b82032c
YZ		 3014out:
3015 mutex_unlock(&uuid_mutex);
3016 return ret;
3017}
3018
0d81ba5d 3019static int read_one_dev(struct btrfs_root *root,
0b86a832
CM		 3020 struct extent_buffer *leaf,
3021 struct btrfs_dev_item *dev_item)
3022{
3023 struct btrfs_device *device;
3024 u64 devid;
3025 int ret;
2b82032c 3026 u8 fs_uuid[BTRFS_UUID_SIZE];
a443755f
CM		 3027 u8 dev_uuid[BTRFS_UUID_SIZE];
3028
0b86a832 3029 devid = btrfs_device_id(leaf, dev_item);
a443755f
CM		 3030 read_extent_buffer(leaf, dev_uuid,
3031 (unsigned long)btrfs_device_uuid(dev_item),
3032 BTRFS_UUID_SIZE);
2b82032c
YZ		 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);
e4404d6e 3039 if (ret && !btrfs_test_opt(root, DEGRADED))
2b82032c 3040 return ret;
2b82032c
YZ		 3041 }
3042
3043 device = btrfs_find_device(root, devid, dev_uuid, fs_uuid);
3044 if (!device || !device->bdev) {
e4404d6e 3045 if (!btrfs_test_opt(root, DEGRADED))
2b82032c
YZ		 3046 return -EIO;
3047
3048 if (!device) {
d397712b
CM		 3049 printk(KERN_WARNING "warning devid %llu missing\n",
3050 (unsigned long long)devid);
2b82032c
YZ		 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;
6324fbf3 3062 }
0b86a832
CM		 3063
3064 fill_device_from_item(leaf, dev_item, device);
3065 device->dev_root = root->fs_info->dev_root;
dfe25020 3066 device->in_fs_metadata = 1;
2b82032c
YZ		 3067 if (device->writeable)
3068 device->fs_devices->total_rw_bytes += device->total_bytes;
0b86a832 3069 ret = 0;
0b86a832
CM		 3070 return ret;
3071}
3072
0d81ba5d
CM		 3073int 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
e4404d6e 3082int btrfs_read_sys_array(struct btrfs_root *root)
0b86a832
CM		 3083{
3084 struct btrfs_super_block *super_copy = &root->fs_info->super_copy;
a061fc8d 3085 struct extent_buffer *sb;
0b86a832 3086 struct btrfs_disk_key *disk_key;
0b86a832 3087 struct btrfs_chunk *chunk;
84eed90f
CM		 3088 u8 *ptr;
3089 unsigned long sb_ptr;
3090 int ret = 0;
0b86a832
CM		 3091 u32 num_stripes;
3092 u32 array_size;
3093 u32 len = 0;
0b86a832 3094 u32 cur;
84eed90f 3095 struct btrfs_key key;
0b86a832 3096
e4404d6e 3097 sb = btrfs_find_create_tree_block(root, BTRFS_SUPER_INFO_OFFSET,
a061fc8d
CM		 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);
0b86a832
CM		 3103 array_size = btrfs_super_sys_array_size(super_copy);
3104
0b86a832
CM		 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
a061fc8d 3113 len = sizeof(*disk_key); ptr += len;
0b86a832
CM		 3114 sb_ptr += len;
3115 cur += len;
3116
0d81ba5d 3117 if (key.type == BTRFS_CHUNK_ITEM_KEY) {
0b86a832 3118 chunk = (struct btrfs_chunk *)sb_ptr;
0d81ba5d 3119 ret = read_one_chunk(root, &key, sb, chunk);
84eed90f
CM		 3120 if (ret)
3121 break;
0b86a832
CM		 3122 num_stripes = btrfs_chunk_num_stripes(sb, chunk);
3123 len = btrfs_chunk_item_size(num_stripes);
3124 } else {
84eed90f
CM		 3125 ret = -EIO;
3126 break;
0b86a832
CM		 3127 }
3128 ptr += len;
3129 sb_ptr += len;
3130 cur += len;
3131 }
a061fc8d 3132 free_extent_buffer(sb);
84eed90f 3133 return ret;
0b86a832
CM		 3134}
3135
3136int 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;
3158again:
3159 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
d397712b 3160 while (1) {
0b86a832
CM		 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);
0d81ba5d 3179 ret = read_one_dev(root, leaf, dev_item);
2b82032c
YZ		 3180 if (ret)
3181 goto error;
0b86a832
CM		 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);
2b82032c
YZ		 3187 if (ret)
3188 goto error;
0b86a832
CM		 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 }
0b86a832
CM		 3197 ret = 0;
3198error:
2b82032c 3199 btrfs_free_path(path);
0b86a832
CM		 3200 return ret;
3201}
Linux 6.x block layer and io_uring tree(s)