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ARM: S5PC100: gpio.h cleanup
[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>
5a0e3ad6 20#include <linux/slab.h>
8a4b83cc 21#include <linux/buffer_head.h>
f2d8d74d 22#include <linux/blkdev.h>
788f20eb 23#include <linux/random.h>
b765ead5 24#include <linux/iocontext.h>
593060d7 25#include <asm/div64.h>
4b4e25f2 26#include "compat.h"
0b86a832
CM		 27#include "ctree.h"
28#include "extent_map.h"
29#include "disk-io.h"
30#include "transaction.h"
31#include "print-tree.h"
32#include "volumes.h"
8b712842 33#include "async-thread.h"
0b86a832 34
593060d7
CM		 35struct map_lookup {
36 u64 type;
37 int io_align;
38 int io_width;
39 int stripe_len;
40 int sector_size;
41 int num_stripes;
321aecc6 42 int sub_stripes;
cea9e445 43 struct btrfs_bio_stripe stripes[];
593060d7
CM		 44};
45
2b82032c
YZ		 46static int init_first_rw_device(struct btrfs_trans_handle *trans,
47 struct btrfs_root *root,
48 struct btrfs_device *device);
49static int btrfs_relocate_sys_chunks(struct btrfs_root *root);
50
593060d7 51#define map_lookup_size(n) (sizeof(struct map_lookup) + \
cea9e445 52 (sizeof(struct btrfs_bio_stripe) * (n)))
593060d7 53
8a4b83cc
CM		 54static DEFINE_MUTEX(uuid_mutex);
55static LIST_HEAD(fs_uuids);
56
a061fc8d
CM		 57void btrfs_lock_volumes(void)
58{
59 mutex_lock(&uuid_mutex);
60}
61
62void btrfs_unlock_volumes(void)
63{
64 mutex_unlock(&uuid_mutex);
65}
66
7d9eb12c
CM		 67static void lock_chunks(struct btrfs_root *root)
68{
7d9eb12c
CM		 69 mutex_lock(&root->fs_info->chunk_mutex);
70}
71
72static void unlock_chunks(struct btrfs_root *root)
73{
7d9eb12c
CM		 74 mutex_unlock(&root->fs_info->chunk_mutex);
75}
76
e4404d6e
YZ		 77static void free_fs_devices(struct btrfs_fs_devices *fs_devices)
78{
79 struct btrfs_device *device;
80 WARN_ON(fs_devices->opened);
81 while (!list_empty(&fs_devices->devices)) {
82 device = list_entry(fs_devices->devices.next,
83 struct btrfs_device, dev_list);
84 list_del(&device->dev_list);
85 kfree(device->name);
86 kfree(device);
87 }
88 kfree(fs_devices);
89}
90
8a4b83cc
CM		 91int btrfs_cleanup_fs_uuids(void)
92{
93 struct btrfs_fs_devices *fs_devices;
8a4b83cc 94
2b82032c
YZ		 95 while (!list_empty(&fs_uuids)) {
96 fs_devices = list_entry(fs_uuids.next,
97 struct btrfs_fs_devices, list);
98 list_del(&fs_devices->list);
e4404d6e 99 free_fs_devices(fs_devices);
8a4b83cc
CM		 100 }
101 return 0;
102}
103
a1b32a59
CM		 104static noinline struct btrfs_device *__find_device(struct list_head *head,
105 u64 devid, u8 *uuid)
8a4b83cc
CM		 106{
107 struct btrfs_device *dev;
8a4b83cc 108
c6e30871 109 list_for_each_entry(dev, head, dev_list) {
a443755f 110 if (dev->devid == devid &&
8f18cf13 111 (!uuid || !memcmp(dev->uuid, uuid, BTRFS_UUID_SIZE))) {
8a4b83cc 112 return dev;
a443755f 113 }
8a4b83cc
CM		 114 }
115 return NULL;
116}
117
a1b32a59 118static noinline struct btrfs_fs_devices *find_fsid(u8 *fsid)
8a4b83cc 119{
8a4b83cc
CM		 120 struct btrfs_fs_devices *fs_devices;
121
c6e30871 122 list_for_each_entry(fs_devices, &fs_uuids, list) {
8a4b83cc
CM		 123 if (memcmp(fsid, fs_devices->fsid, BTRFS_FSID_SIZE) == 0)
124 return fs_devices;
125 }
126 return NULL;
127}
128
ffbd517d
CM		 129static void requeue_list(struct btrfs_pending_bios *pending_bios,
130 struct bio *head, struct bio *tail)
131{
132
133 struct bio *old_head;
134
135 old_head = pending_bios->head;
136 pending_bios->head = head;
137 if (pending_bios->tail)
138 tail->bi_next = old_head;
139 else
140 pending_bios->tail = tail;
141}
142
8b712842
CM		 143/*
144 * we try to collect pending bios for a device so we don't get a large
145 * number of procs sending bios down to the same device. This greatly
146 * improves the schedulers ability to collect and merge the bios.
147 *
148 * But, it also turns into a long list of bios to process and that is sure
149 * to eventually make the worker thread block. The solution here is to
150 * make some progress and then put this work struct back at the end of
151 * the list if the block device is congested. This way, multiple devices
152 * can make progress from a single worker thread.
153 */
d397712b 154static noinline int run_scheduled_bios(struct btrfs_device *device)
8b712842
CM		 155{
156 struct bio *pending;
157 struct backing_dev_info *bdi;
b64a2851 158 struct btrfs_fs_info *fs_info;
ffbd517d 159 struct btrfs_pending_bios *pending_bios;
8b712842
CM		 160 struct bio *tail;
161 struct bio *cur;
162 int again = 0;
ffbd517d
CM		 163 unsigned long num_run;
164 unsigned long num_sync_run;
d644d8a1 165 unsigned long batch_run = 0;
b64a2851 166 unsigned long limit;
b765ead5 167 unsigned long last_waited = 0;
d84275c9 168 int force_reg = 0;
8b712842 169
bedf762b 170 bdi = blk_get_backing_dev_info(device->bdev);
b64a2851
CM		 171 fs_info = device->dev_root->fs_info;
172 limit = btrfs_async_submit_limit(fs_info);
173 limit = limit * 2 / 3;
174
ffbd517d
CM		 175 /* we want to make sure that every time we switch from the sync
176 * list to the normal list, we unplug
177 */
178 num_sync_run = 0;
179
8b712842
CM		 180loop:
181 spin_lock(&device->io_lock);
182
a6837051 183loop_lock:
d84275c9 184 num_run = 0;
ffbd517d 185
8b712842
CM		 186 /* take all the bios off the list at once and process them
187 * later on (without the lock held). But, remember the
188 * tail and other pointers so the bios can be properly reinserted
189 * into the list if we hit congestion
190 */
d84275c9 191 if (!force_reg && device->pending_sync_bios.head) {
ffbd517d 192 pending_bios = &device->pending_sync_bios;
d84275c9
CM		 193 force_reg = 1;
194 } else {
ffbd517d 195 pending_bios = &device->pending_bios;
d84275c9
CM		 196 force_reg = 0;
197 }
ffbd517d
CM		 198
199 pending = pending_bios->head;
200 tail = pending_bios->tail;
8b712842 201 WARN_ON(pending && !tail);
8b712842
CM		 202
203 /*
204 * if pending was null this time around, no bios need processing
205 * at all and we can stop. Otherwise it'll loop back up again
206 * and do an additional check so no bios are missed.
207 *
208 * device->running_pending is used to synchronize with the
209 * schedule_bio code.
210 */
ffbd517d
CM		 211 if (device->pending_sync_bios.head == NULL &&
212 device->pending_bios.head == NULL) {
8b712842
CM		 213 again = 0;
214 device->running_pending = 0;
ffbd517d
CM		 215 } else {
216 again = 1;
217 device->running_pending = 1;
8b712842 218 }
ffbd517d
CM		 219
220 pending_bios->head = NULL;
221 pending_bios->tail = NULL;
222
8b712842
CM		 223 spin_unlock(&device->io_lock);
224
ffbd517d
CM		 225 /*
226 * if we're doing the regular priority list, make sure we unplug
227 * for any high prio bios we've sent down
228 */
229 if (pending_bios == &device->pending_bios && num_sync_run > 0) {
230 num_sync_run = 0;
231 blk_run_backing_dev(bdi, NULL);
232 }
233
d397712b 234 while (pending) {
ffbd517d
CM		 235
236 rmb();
d84275c9
CM		 237 /* we want to work on both lists, but do more bios on the
238 * sync list than the regular list
239 */
240 if ((num_run > 32 &&
241 pending_bios != &device->pending_sync_bios &&
242 device->pending_sync_bios.head) ||
243 (num_run > 64 && pending_bios == &device->pending_sync_bios &&
244 device->pending_bios.head)) {
ffbd517d
CM		 245 spin_lock(&device->io_lock);
246 requeue_list(pending_bios, pending, tail);
247 goto loop_lock;
248 }
249
8b712842
CM		 250 cur = pending;
251 pending = pending->bi_next;
252 cur->bi_next = NULL;
b64a2851
CM		 253 atomic_dec(&fs_info->nr_async_bios);
254
255 if (atomic_read(&fs_info->nr_async_bios) < limit &&
256 waitqueue_active(&fs_info->async_submit_wait))
257 wake_up(&fs_info->async_submit_wait);
492bb6de
CM		 258
259 BUG_ON(atomic_read(&cur->bi_cnt) == 0);
d644d8a1 260
1f98a13f 261 if (bio_rw_flagged(cur, BIO_RW_SYNCIO))
ffbd517d
CM		 262 num_sync_run++;
263
5ff7ba3a
CM		 264 submit_bio(cur->bi_rw, cur);
265 num_run++;
266 batch_run++;
ffbd517d
CM		 267 if (need_resched()) {
268 if (num_sync_run) {
269 blk_run_backing_dev(bdi, NULL);
270 num_sync_run = 0;
271 }
272 cond_resched();
273 }
8b712842
CM		 274
275 /*
276 * we made progress, there is more work to do and the bdi
277 * is now congested. Back off and let other work structs
278 * run instead
279 */
57fd5a5f 280 if (pending && bdi_write_congested(bdi) && batch_run > 8 &&
5f2cc086 281 fs_info->fs_devices->open_devices > 1) {
b765ead5 282 struct io_context *ioc;
8b712842 283
b765ead5
CM		 284 ioc = current->io_context;
285
286 /*
287 * the main goal here is that we don't want to
288 * block if we're going to be able to submit
289 * more requests without blocking.
290 *
291 * This code does two great things, it pokes into
292 * the elevator code from a filesystem _and_
293 * it makes assumptions about how batching works.
294 */
295 if (ioc && ioc->nr_batch_requests > 0 &&
296 time_before(jiffies, ioc->last_waited + HZ/50UL) &&
297 (last_waited == 0 ||
298 ioc->last_waited == last_waited)) {
299 /*
300 * we want to go through our batch of
301 * requests and stop. So, we copy out
302 * the ioc->last_waited time and test
303 * against it before looping
304 */
305 last_waited = ioc->last_waited;
ffbd517d
CM		 306 if (need_resched()) {
307 if (num_sync_run) {
308 blk_run_backing_dev(bdi, NULL);
309 num_sync_run = 0;
310 }
311 cond_resched();
312 }
b765ead5
CM		 313 continue;
314 }
8b712842 315 spin_lock(&device->io_lock);
ffbd517d 316 requeue_list(pending_bios, pending, tail);
a6837051 317 device->running_pending = 1;
8b712842
CM		 318
319 spin_unlock(&device->io_lock);
320 btrfs_requeue_work(&device->work);
321 goto done;
322 }
323 }
ffbd517d
CM		 324
325 if (num_sync_run) {
326 num_sync_run = 0;
327 blk_run_backing_dev(bdi, NULL);
328 }
bedf762b
CM		 329 /*
330 * IO has already been through a long path to get here. Checksumming,
331 * async helper threads, perhaps compression. We've done a pretty
332 * good job of collecting a batch of IO and should just unplug
333 * the device right away.
334 *
335 * This will help anyone who is waiting on the IO, they might have
336 * already unplugged, but managed to do so before the bio they
337 * cared about found its way down here.
338 */
339 blk_run_backing_dev(bdi, NULL);
51684082
CM		 340
341 cond_resched();
342 if (again)
343 goto loop;
344
345 spin_lock(&device->io_lock);
346 if (device->pending_bios.head || device->pending_sync_bios.head)
347 goto loop_lock;
348 spin_unlock(&device->io_lock);
349
8b712842
CM		 350done:
351 return 0;
352}
353
b2950863 354static void pending_bios_fn(struct btrfs_work *work)
8b712842
CM		 355{
356 struct btrfs_device *device;
357
358 device = container_of(work, struct btrfs_device, work);
359 run_scheduled_bios(device);
360}
361
a1b32a59 362static noinline int device_list_add(const char *path,
8a4b83cc
CM		 363 struct btrfs_super_block *disk_super,
364 u64 devid, struct btrfs_fs_devices **fs_devices_ret)
365{
366 struct btrfs_device *device;
367 struct btrfs_fs_devices *fs_devices;
368 u64 found_transid = btrfs_super_generation(disk_super);
3a0524dc 369 char *name;
8a4b83cc
CM		 370
371 fs_devices = find_fsid(disk_super->fsid);
372 if (!fs_devices) {
515dc322 373 fs_devices = kzalloc(sizeof(*fs_devices), GFP_NOFS);
8a4b83cc
CM		 374 if (!fs_devices)
375 return -ENOMEM;
376 INIT_LIST_HEAD(&fs_devices->devices);
b3075717 377 INIT_LIST_HEAD(&fs_devices->alloc_list);
8a4b83cc
CM		 378 list_add(&fs_devices->list, &fs_uuids);
379 memcpy(fs_devices->fsid, disk_super->fsid, BTRFS_FSID_SIZE);
380 fs_devices->latest_devid = devid;
381 fs_devices->latest_trans = found_transid;
e5e9a520 382 mutex_init(&fs_devices->device_list_mutex);
8a4b83cc
CM		 383 device = NULL;
384 } else {
a443755f
CM		 385 device = __find_device(&fs_devices->devices, devid,
386 disk_super->dev_item.uuid);
8a4b83cc
CM		 387 }
388 if (!device) {
2b82032c
YZ		 389 if (fs_devices->opened)
390 return -EBUSY;
391
8a4b83cc
CM		 392 device = kzalloc(sizeof(*device), GFP_NOFS);
393 if (!device) {
394 /* we can safely leave the fs_devices entry around */
395 return -ENOMEM;
396 }
397 device->devid = devid;
8b712842 398 device->work.func = pending_bios_fn;
a443755f
CM		 399 memcpy(device->uuid, disk_super->dev_item.uuid,
400 BTRFS_UUID_SIZE);
f2984462 401 device->barriers = 1;
b248a415 402 spin_lock_init(&device->io_lock);
8a4b83cc
CM		 403 device->name = kstrdup(path, GFP_NOFS);
404 if (!device->name) {
405 kfree(device);
406 return -ENOMEM;
407 }
2b82032c 408 INIT_LIST_HEAD(&device->dev_alloc_list);
e5e9a520
CM		 409
410 mutex_lock(&fs_devices->device_list_mutex);
8a4b83cc 411 list_add(&device->dev_list, &fs_devices->devices);
e5e9a520
CM		 412 mutex_unlock(&fs_devices->device_list_mutex);
413
2b82032c 414 device->fs_devices = fs_devices;
8a4b83cc 415 fs_devices->num_devices++;
3a0524dc
TH		 416 } else if (strcmp(device->name, path)) {
417 name = kstrdup(path, GFP_NOFS);
418 if (!name)
419 return -ENOMEM;
420 kfree(device->name);
421 device->name = name;
8a4b83cc
CM		 422 }
423
424 if (found_transid > fs_devices->latest_trans) {
425 fs_devices->latest_devid = devid;
426 fs_devices->latest_trans = found_transid;
427 }
8a4b83cc
CM		 428 *fs_devices_ret = fs_devices;
429 return 0;
430}
431
e4404d6e
YZ		 432static struct btrfs_fs_devices *clone_fs_devices(struct btrfs_fs_devices *orig)
433{
434 struct btrfs_fs_devices *fs_devices;
435 struct btrfs_device *device;
436 struct btrfs_device *orig_dev;
437
438 fs_devices = kzalloc(sizeof(*fs_devices), GFP_NOFS);
439 if (!fs_devices)
440 return ERR_PTR(-ENOMEM);
441
442 INIT_LIST_HEAD(&fs_devices->devices);
443 INIT_LIST_HEAD(&fs_devices->alloc_list);
444 INIT_LIST_HEAD(&fs_devices->list);
e5e9a520 445 mutex_init(&fs_devices->device_list_mutex);
e4404d6e
YZ		 446 fs_devices->latest_devid = orig->latest_devid;
447 fs_devices->latest_trans = orig->latest_trans;
448 memcpy(fs_devices->fsid, orig->fsid, sizeof(fs_devices->fsid));
449
e5e9a520 450 mutex_lock(&orig->device_list_mutex);
e4404d6e
YZ		 451 list_for_each_entry(orig_dev, &orig->devices, dev_list) {
452 device = kzalloc(sizeof(*device), GFP_NOFS);
453 if (!device)
454 goto error;
455
456 device->name = kstrdup(orig_dev->name, GFP_NOFS);
fd2696f3
JL		 457 if (!device->name) {
458 kfree(device);
e4404d6e 459 goto error;
fd2696f3 460 }
e4404d6e
YZ		 461
462 device->devid = orig_dev->devid;
463 device->work.func = pending_bios_fn;
464 memcpy(device->uuid, orig_dev->uuid, sizeof(device->uuid));
465 device->barriers = 1;
466 spin_lock_init(&device->io_lock);
467 INIT_LIST_HEAD(&device->dev_list);
468 INIT_LIST_HEAD(&device->dev_alloc_list);
469
470 list_add(&device->dev_list, &fs_devices->devices);
471 device->fs_devices = fs_devices;
472 fs_devices->num_devices++;
473 }
e5e9a520 474 mutex_unlock(&orig->device_list_mutex);
e4404d6e
YZ		 475 return fs_devices;
476error:
e5e9a520 477 mutex_unlock(&orig->device_list_mutex);
e4404d6e
YZ		 478 free_fs_devices(fs_devices);
479 return ERR_PTR(-ENOMEM);
480}
481
dfe25020
CM		 482int btrfs_close_extra_devices(struct btrfs_fs_devices *fs_devices)
483{
c6e30871 484 struct btrfs_device *device, *next;
dfe25020
CM		 485
486 mutex_lock(&uuid_mutex);
487again:
e5e9a520 488 mutex_lock(&fs_devices->device_list_mutex);
c6e30871 489 list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) {
2b82032c
YZ		 490 if (device->in_fs_metadata)
491 continue;
492
493 if (device->bdev) {
15916de8 494 close_bdev_exclusive(device->bdev, device->mode);
2b82032c
YZ		 495 device->bdev = NULL;
496 fs_devices->open_devices--;
497 }
498 if (device->writeable) {
499 list_del_init(&device->dev_alloc_list);
500 device->writeable = 0;
501 fs_devices->rw_devices--;
502 }
e4404d6e
YZ		 503 list_del_init(&device->dev_list);
504 fs_devices->num_devices--;
505 kfree(device->name);
506 kfree(device);
dfe25020 507 }
e5e9a520 508 mutex_unlock(&fs_devices->device_list_mutex);
2b82032c
YZ		 509
510 if (fs_devices->seed) {
511 fs_devices = fs_devices->seed;
2b82032c
YZ		 512 goto again;
513 }
514
dfe25020
CM		 515 mutex_unlock(&uuid_mutex);
516 return 0;
517}
a0af469b 518
2b82032c 519static int __btrfs_close_devices(struct btrfs_fs_devices *fs_devices)
8a4b83cc 520{
8a4b83cc 521 struct btrfs_device *device;
e4404d6e 522
2b82032c
YZ		 523 if (--fs_devices->opened > 0)
524 return 0;
8a4b83cc 525
c6e30871 526 list_for_each_entry(device, &fs_devices->devices, dev_list) {
8a4b83cc 527 if (device->bdev) {
15916de8 528 close_bdev_exclusive(device->bdev, device->mode);
a0af469b 529 fs_devices->open_devices--;
8a4b83cc 530 }
2b82032c
YZ		 531 if (device->writeable) {
532 list_del_init(&device->dev_alloc_list);
533 fs_devices->rw_devices--;
534 }
535
8a4b83cc 536 device->bdev = NULL;
2b82032c 537 device->writeable = 0;
dfe25020 538 device->in_fs_metadata = 0;
8a4b83cc 539 }
e4404d6e
YZ		 540 WARN_ON(fs_devices->open_devices);
541 WARN_ON(fs_devices->rw_devices);
2b82032c
YZ		 542 fs_devices->opened = 0;
543 fs_devices->seeding = 0;
2b82032c 544
8a4b83cc
CM		 545 return 0;
546}
547
2b82032c
YZ		 548int btrfs_close_devices(struct btrfs_fs_devices *fs_devices)
549{
e4404d6e 550 struct btrfs_fs_devices *seed_devices = NULL;
2b82032c
YZ		 551 int ret;
552
553 mutex_lock(&uuid_mutex);
554 ret = __btrfs_close_devices(fs_devices);
e4404d6e
YZ		 555 if (!fs_devices->opened) {
556 seed_devices = fs_devices->seed;
557 fs_devices->seed = NULL;
558 }
2b82032c 559 mutex_unlock(&uuid_mutex);
e4404d6e
YZ		 560
561 while (seed_devices) {
562 fs_devices = seed_devices;
563 seed_devices = fs_devices->seed;
564 __btrfs_close_devices(fs_devices);
565 free_fs_devices(fs_devices);
566 }
2b82032c
YZ		 567 return ret;
568}
569
e4404d6e
YZ		 570static int __btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
571 fmode_t flags, void *holder)
8a4b83cc
CM		 572{
573 struct block_device *bdev;
574 struct list_head *head = &fs_devices->devices;
8a4b83cc 575 struct btrfs_device *device;
a0af469b
CM		 576 struct block_device *latest_bdev = NULL;
577 struct buffer_head *bh;
578 struct btrfs_super_block *disk_super;
579 u64 latest_devid = 0;
580 u64 latest_transid = 0;
a0af469b 581 u64 devid;
2b82032c 582 int seeding = 1;
a0af469b 583 int ret = 0;
8a4b83cc 584
c6e30871 585 list_for_each_entry(device, head, dev_list) {
c1c4d91c
CM		 586 if (device->bdev)
587 continue;
dfe25020
CM		 588 if (!device->name)
589 continue;
590
15916de8 591 bdev = open_bdev_exclusive(device->name, flags, holder);
8a4b83cc 592 if (IS_ERR(bdev)) {
d397712b 593 printk(KERN_INFO "open %s failed\n", device->name);
a0af469b 594 goto error;
8a4b83cc 595 }
a061fc8d 596 set_blocksize(bdev, 4096);
a0af469b 597
a512bbf8 598 bh = btrfs_read_dev_super(bdev);
a0af469b
CM		 599 if (!bh)
600 goto error_close;
601
602 disk_super = (struct btrfs_super_block *)bh->b_data;
a343832f 603 devid = btrfs_stack_device_id(&disk_super->dev_item);
a0af469b
CM		 604 if (devid != device->devid)
605 goto error_brelse;
606
2b82032c
YZ		 607 if (memcmp(device->uuid, disk_super->dev_item.uuid,
608 BTRFS_UUID_SIZE))
609 goto error_brelse;
610
611 device->generation = btrfs_super_generation(disk_super);
612 if (!latest_transid || device->generation > latest_transid) {
a0af469b 613 latest_devid = devid;
2b82032c 614 latest_transid = device->generation;
a0af469b
CM		 615 latest_bdev = bdev;
616 }
617
2b82032c
YZ		 618 if (btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_SEEDING) {
619 device->writeable = 0;
620 } else {
621 device->writeable = !bdev_read_only(bdev);
622 seeding = 0;
623 }
624
8a4b83cc 625 device->bdev = bdev;
dfe25020 626 device->in_fs_metadata = 0;
15916de8
CM		 627 device->mode = flags;
628
c289811c
CM		 629 if (!blk_queue_nonrot(bdev_get_queue(bdev)))
630 fs_devices->rotating = 1;
631
a0af469b 632 fs_devices->open_devices++;
2b82032c
YZ		 633 if (device->writeable) {
634 fs_devices->rw_devices++;
635 list_add(&device->dev_alloc_list,
636 &fs_devices->alloc_list);
637 }
a0af469b 638 continue;
a061fc8d 639
a0af469b
CM		 640error_brelse:
641 brelse(bh);
642error_close:
97288f2c 643 close_bdev_exclusive(bdev, FMODE_READ);
a0af469b
CM		 644error:
645 continue;
8a4b83cc 646 }
a0af469b
CM		 647 if (fs_devices->open_devices == 0) {
648 ret = -EIO;
649 goto out;
650 }
2b82032c
YZ		 651 fs_devices->seeding = seeding;
652 fs_devices->opened = 1;
a0af469b
CM		 653 fs_devices->latest_bdev = latest_bdev;
654 fs_devices->latest_devid = latest_devid;
655 fs_devices->latest_trans = latest_transid;
2b82032c 656 fs_devices->total_rw_bytes = 0;
a0af469b 657out:
2b82032c
YZ		 658 return ret;
659}
660
661int btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
97288f2c 662 fmode_t flags, void *holder)
2b82032c
YZ		 663{
664 int ret;
665
666 mutex_lock(&uuid_mutex);
667 if (fs_devices->opened) {
e4404d6e
YZ		 668 fs_devices->opened++;
669 ret = 0;
2b82032c 670 } else {
15916de8 671 ret = __btrfs_open_devices(fs_devices, flags, holder);
2b82032c 672 }
8a4b83cc 673 mutex_unlock(&uuid_mutex);
8a4b83cc
CM		 674 return ret;
675}
676
97288f2c 677int btrfs_scan_one_device(const char *path, fmode_t flags, void *holder,
8a4b83cc
CM		 678 struct btrfs_fs_devices **fs_devices_ret)
679{
680 struct btrfs_super_block *disk_super;
681 struct block_device *bdev;
682 struct buffer_head *bh;
683 int ret;
684 u64 devid;
f2984462 685 u64 transid;
8a4b83cc
CM		 686
687 mutex_lock(&uuid_mutex);
688
15916de8 689 bdev = open_bdev_exclusive(path, flags, holder);
8a4b83cc
CM		 690
691 if (IS_ERR(bdev)) {
8a4b83cc
CM		 692 ret = PTR_ERR(bdev);
693 goto error;
694 }
695
696 ret = set_blocksize(bdev, 4096);
697 if (ret)
698 goto error_close;
a512bbf8 699 bh = btrfs_read_dev_super(bdev);
8a4b83cc
CM		 700 if (!bh) {
701 ret = -EIO;
702 goto error_close;
703 }
704 disk_super = (struct btrfs_super_block *)bh->b_data;
a343832f 705 devid = btrfs_stack_device_id(&disk_super->dev_item);
f2984462 706 transid = btrfs_super_generation(disk_super);
7ae9c09d 707 if (disk_super->label[0])
d397712b 708 printk(KERN_INFO "device label %s ", disk_super->label);
7ae9c09d
CM		 709 else {
710 /* FIXME, make a readl uuid parser */
d397712b 711 printk(KERN_INFO "device fsid %llx-%llx ",
7ae9c09d
CM		 712 *(unsigned long long *)disk_super->fsid,
713 *(unsigned long long *)(disk_super->fsid + 8));
714 }
119e10cf 715 printk(KERN_CONT "devid %llu transid %llu %s\n",
d397712b 716 (unsigned long long)devid, (unsigned long long)transid, path);
8a4b83cc
CM		 717 ret = device_list_add(path, disk_super, devid, fs_devices_ret);
718
8a4b83cc
CM		 719 brelse(bh);
720error_close:
15916de8 721 close_bdev_exclusive(bdev, flags);
8a4b83cc
CM		 722error:
723 mutex_unlock(&uuid_mutex);
724 return ret;
725}
0b86a832
CM		 726
727/*
728 * this uses a pretty simple search, the expectation is that it is
729 * called very infrequently and that a given device has a small number
730 * of extents
731 */
ba1bf481
JB		 732int find_free_dev_extent(struct btrfs_trans_handle *trans,
733 struct btrfs_device *device, u64 num_bytes,
734 u64 *start, u64 *max_avail)
0b86a832
CM		 735{
736 struct btrfs_key key;
737 struct btrfs_root *root = device->dev_root;
738 struct btrfs_dev_extent *dev_extent = NULL;
2b82032c 739 struct btrfs_path *path;
0b86a832
CM		 740 u64 hole_size = 0;
741 u64 last_byte = 0;
742 u64 search_start = 0;
743 u64 search_end = device->total_bytes;
744 int ret;
745 int slot = 0;
746 int start_found;
747 struct extent_buffer *l;
748
2b82032c
YZ		 749 path = btrfs_alloc_path();
750 if (!path)
751 return -ENOMEM;
0b86a832 752 path->reada = 2;
2b82032c 753 start_found = 0;
0b86a832
CM		 754
755 /* FIXME use last free of some kind */
756
8a4b83cc
CM		 757 /* we don't want to overwrite the superblock on the drive,
758 * so we make sure to start at an offset of at least 1MB
759 */
760 search_start = max((u64)1024 * 1024, search_start);
8f18cf13
CM		 761
762 if (root->fs_info->alloc_start + num_bytes <= device->total_bytes)
763 search_start = max(root->fs_info->alloc_start, search_start);
764
0b86a832
CM		 765 key.objectid = device->devid;
766 key.offset = search_start;
767 key.type = BTRFS_DEV_EXTENT_KEY;
768 ret = btrfs_search_slot(trans, root, &key, path, 0, 0);
769 if (ret < 0)
770 goto error;
1fcbac58
YZ		 771 if (ret > 0) {
772 ret = btrfs_previous_item(root, path, key.objectid, key.type);
773 if (ret < 0)
774 goto error;
775 if (ret > 0)
776 start_found = 1;
777 }
0b86a832
CM		 778 l = path->nodes[0];
779 btrfs_item_key_to_cpu(l, &key, path->slots[0]);
780 while (1) {
781 l = path->nodes[0];
782 slot = path->slots[0];
783 if (slot >= btrfs_header_nritems(l)) {
784 ret = btrfs_next_leaf(root, path);
785 if (ret == 0)
786 continue;
787 if (ret < 0)
788 goto error;
789no_more_items:
790 if (!start_found) {
791 if (search_start >= search_end) {
792 ret = -ENOSPC;
793 goto error;
794 }
795 *start = search_start;
796 start_found = 1;
797 goto check_pending;
798 }
799 *start = last_byte > search_start ?
800 last_byte : search_start;
801 if (search_end <= *start) {
802 ret = -ENOSPC;
803 goto error;
804 }
805 goto check_pending;
806 }
807 btrfs_item_key_to_cpu(l, &key, slot);
808
809 if (key.objectid < device->devid)
810 goto next;
811
812 if (key.objectid > device->devid)
813 goto no_more_items;
814
815 if (key.offset >= search_start && key.offset > last_byte &&
816 start_found) {
817 if (last_byte < search_start)
818 last_byte = search_start;
819 hole_size = key.offset - last_byte;
9779b72f
CM		 820
821 if (hole_size > *max_avail)
822 *max_avail = hole_size;
823
0b86a832
CM		 824 if (key.offset > last_byte &&
825 hole_size >= num_bytes) {
826 *start = last_byte;
827 goto check_pending;
828 }
829 }
d397712b 830 if (btrfs_key_type(&key) != BTRFS_DEV_EXTENT_KEY)
0b86a832 831 goto next;
0b86a832
CM		 832
833 start_found = 1;
834 dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent);
835 last_byte = key.offset + btrfs_dev_extent_length(l, dev_extent);
836next:
837 path->slots[0]++;
838 cond_resched();
839 }
840check_pending:
841 /* we have to make sure we didn't find an extent that has already
842 * been allocated by the map tree or the original allocation
843 */
0b86a832
CM		 844 BUG_ON(*start < search_start);
845
6324fbf3 846 if (*start + num_bytes > search_end) {
0b86a832
CM		 847 ret = -ENOSPC;
848 goto error;
849 }
850 /* check for pending inserts here */
2b82032c 851 ret = 0;
0b86a832
CM		 852
853error:
2b82032c 854 btrfs_free_path(path);
0b86a832
CM		 855 return ret;
856}
857
b2950863 858static int btrfs_free_dev_extent(struct btrfs_trans_handle *trans,
8f18cf13
CM		 859 struct btrfs_device *device,
860 u64 start)
861{
862 int ret;
863 struct btrfs_path *path;
864 struct btrfs_root *root = device->dev_root;
865 struct btrfs_key key;
a061fc8d
CM		 866 struct btrfs_key found_key;
867 struct extent_buffer *leaf = NULL;
868 struct btrfs_dev_extent *extent = NULL;
8f18cf13
CM		 869
870 path = btrfs_alloc_path();
871 if (!path)
872 return -ENOMEM;
873
874 key.objectid = device->devid;
875 key.offset = start;
876 key.type = BTRFS_DEV_EXTENT_KEY;
877
878 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
a061fc8d
CM		 879 if (ret > 0) {
880 ret = btrfs_previous_item(root, path, key.objectid,
881 BTRFS_DEV_EXTENT_KEY);
882 BUG_ON(ret);
883 leaf = path->nodes[0];
884 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
885 extent = btrfs_item_ptr(leaf, path->slots[0],
886 struct btrfs_dev_extent);
887 BUG_ON(found_key.offset > start || found_key.offset +
888 btrfs_dev_extent_length(leaf, extent) < start);
889 ret = 0;
890 } else if (ret == 0) {
891 leaf = path->nodes[0];
892 extent = btrfs_item_ptr(leaf, path->slots[0],
893 struct btrfs_dev_extent);
894 }
8f18cf13
CM		 895 BUG_ON(ret);
896
dfe25020
CM		 897 if (device->bytes_used > 0)
898 device->bytes_used -= btrfs_dev_extent_length(leaf, extent);
8f18cf13
CM		 899 ret = btrfs_del_item(trans, root, path);
900 BUG_ON(ret);
901
902 btrfs_free_path(path);
903 return ret;
904}
905
2b82032c 906int btrfs_alloc_dev_extent(struct btrfs_trans_handle *trans,
0b86a832 907 struct btrfs_device *device,
e17cade2 908 u64 chunk_tree, u64 chunk_objectid,
2b82032c 909 u64 chunk_offset, u64 start, u64 num_bytes)
0b86a832
CM		 910{
911 int ret;
912 struct btrfs_path *path;
913 struct btrfs_root *root = device->dev_root;
914 struct btrfs_dev_extent *extent;
915 struct extent_buffer *leaf;
916 struct btrfs_key key;
917
dfe25020 918 WARN_ON(!device->in_fs_metadata);
0b86a832
CM		 919 path = btrfs_alloc_path();
920 if (!path)
921 return -ENOMEM;
922
0b86a832 923 key.objectid = device->devid;
2b82032c 924 key.offset = start;
0b86a832
CM		 925 key.type = BTRFS_DEV_EXTENT_KEY;
926 ret = btrfs_insert_empty_item(trans, root, path, &key,
927 sizeof(*extent));
928 BUG_ON(ret);
929
930 leaf = path->nodes[0];
931 extent = btrfs_item_ptr(leaf, path->slots[0],
932 struct btrfs_dev_extent);
e17cade2
CM		 933 btrfs_set_dev_extent_chunk_tree(leaf, extent, chunk_tree);
934 btrfs_set_dev_extent_chunk_objectid(leaf, extent, chunk_objectid);
935 btrfs_set_dev_extent_chunk_offset(leaf, extent, chunk_offset);
936
937 write_extent_buffer(leaf, root->fs_info->chunk_tree_uuid,
938 (unsigned long)btrfs_dev_extent_chunk_tree_uuid(extent),
939 BTRFS_UUID_SIZE);
940
0b86a832
CM		 941 btrfs_set_dev_extent_length(leaf, extent, num_bytes);
942 btrfs_mark_buffer_dirty(leaf);
0b86a832
CM		 943 btrfs_free_path(path);
944 return ret;
945}
946
a1b32a59
CM		 947static noinline int find_next_chunk(struct btrfs_root *root,
948 u64 objectid, u64 *offset)
0b86a832
CM		 949{
950 struct btrfs_path *path;
951 int ret;
952 struct btrfs_key key;
e17cade2 953 struct btrfs_chunk *chunk;
0b86a832
CM		 954 struct btrfs_key found_key;
955
956 path = btrfs_alloc_path();
957 BUG_ON(!path);
958
e17cade2 959 key.objectid = objectid;
0b86a832
CM		 960 key.offset = (u64)-1;
961 key.type = BTRFS_CHUNK_ITEM_KEY;
962
963 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
964 if (ret < 0)
965 goto error;
966
967 BUG_ON(ret == 0);
968
969 ret = btrfs_previous_item(root, path, 0, BTRFS_CHUNK_ITEM_KEY);
970 if (ret) {
e17cade2 971 *offset = 0;
0b86a832
CM		 972 } else {
973 btrfs_item_key_to_cpu(path->nodes[0], &found_key,
974 path->slots[0]);
e17cade2
CM		 975 if (found_key.objectid != objectid)
976 *offset = 0;
977 else {
978 chunk = btrfs_item_ptr(path->nodes[0], path->slots[0],
979 struct btrfs_chunk);
980 *offset = found_key.offset +
981 btrfs_chunk_length(path->nodes[0], chunk);
982 }
0b86a832
CM		 983 }
984 ret = 0;
985error:
986 btrfs_free_path(path);
987 return ret;
988}
989
2b82032c 990static noinline int find_next_devid(struct btrfs_root *root, u64 *objectid)
0b86a832
CM		 991{
992 int ret;
993 struct btrfs_key key;
994 struct btrfs_key found_key;
2b82032c
YZ		 995 struct btrfs_path *path;
996
997 root = root->fs_info->chunk_root;
998
999 path = btrfs_alloc_path();
1000 if (!path)
1001 return -ENOMEM;
0b86a832
CM		 1002
1003 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
1004 key.type = BTRFS_DEV_ITEM_KEY;
1005 key.offset = (u64)-1;
1006
1007 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1008 if (ret < 0)
1009 goto error;
1010
1011 BUG_ON(ret == 0);
1012
1013 ret = btrfs_previous_item(root, path, BTRFS_DEV_ITEMS_OBJECTID,
1014 BTRFS_DEV_ITEM_KEY);
1015 if (ret) {
1016 *objectid = 1;
1017 } else {
1018 btrfs_item_key_to_cpu(path->nodes[0], &found_key,
1019 path->slots[0]);
1020 *objectid = found_key.offset + 1;
1021 }
1022 ret = 0;
1023error:
2b82032c 1024 btrfs_free_path(path);
0b86a832
CM		 1025 return ret;
1026}
1027
1028/*
1029 * the device information is stored in the chunk root
1030 * the btrfs_device struct should be fully filled in
1031 */
1032int btrfs_add_device(struct btrfs_trans_handle *trans,
1033 struct btrfs_root *root,
1034 struct btrfs_device *device)
1035{
1036 int ret;
1037 struct btrfs_path *path;
1038 struct btrfs_dev_item *dev_item;
1039 struct extent_buffer *leaf;
1040 struct btrfs_key key;
1041 unsigned long ptr;
0b86a832
CM		 1042
1043 root = root->fs_info->chunk_root;
1044
1045 path = btrfs_alloc_path();
1046 if (!path)
1047 return -ENOMEM;
1048
0b86a832
CM		 1049 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
1050 key.type = BTRFS_DEV_ITEM_KEY;
2b82032c 1051 key.offset = device->devid;
0b86a832
CM		 1052
1053 ret = btrfs_insert_empty_item(trans, root, path, &key,
0d81ba5d 1054 sizeof(*dev_item));
0b86a832
CM		 1055 if (ret)
1056 goto out;
1057
1058 leaf = path->nodes[0];
1059 dev_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dev_item);
1060
1061 btrfs_set_device_id(leaf, dev_item, device->devid);
2b82032c 1062 btrfs_set_device_generation(leaf, dev_item, 0);
0b86a832
CM		 1063 btrfs_set_device_type(leaf, dev_item, device->type);
1064 btrfs_set_device_io_align(leaf, dev_item, device->io_align);
1065 btrfs_set_device_io_width(leaf, dev_item, device->io_width);
1066 btrfs_set_device_sector_size(leaf, dev_item, device->sector_size);
0b86a832
CM		 1067 btrfs_set_device_total_bytes(leaf, dev_item, device->total_bytes);
1068 btrfs_set_device_bytes_used(leaf, dev_item, device->bytes_used);
e17cade2
CM		 1069 btrfs_set_device_group(leaf, dev_item, 0);
1070 btrfs_set_device_seek_speed(leaf, dev_item, 0);
1071 btrfs_set_device_bandwidth(leaf, dev_item, 0);
c3027eb5 1072 btrfs_set_device_start_offset(leaf, dev_item, 0);
0b86a832 1073
0b86a832 1074 ptr = (unsigned long)btrfs_device_uuid(dev_item);
e17cade2 1075 write_extent_buffer(leaf, device->uuid, ptr, BTRFS_UUID_SIZE);
2b82032c
YZ		 1076 ptr = (unsigned long)btrfs_device_fsid(dev_item);
1077 write_extent_buffer(leaf, root->fs_info->fsid, ptr, BTRFS_UUID_SIZE);
0b86a832 1078 btrfs_mark_buffer_dirty(leaf);
0b86a832 1079
2b82032c 1080 ret = 0;
0b86a832
CM		 1081out:
1082 btrfs_free_path(path);
1083 return ret;
1084}
8f18cf13 1085
a061fc8d
CM		 1086static int btrfs_rm_dev_item(struct btrfs_root *root,
1087 struct btrfs_device *device)
1088{
1089 int ret;
1090 struct btrfs_path *path;
a061fc8d 1091 struct btrfs_key key;
a061fc8d
CM		 1092 struct btrfs_trans_handle *trans;
1093
1094 root = root->fs_info->chunk_root;
1095
1096 path = btrfs_alloc_path();
1097 if (!path)
1098 return -ENOMEM;
1099
1100 trans = btrfs_start_transaction(root, 1);
1101 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
1102 key.type = BTRFS_DEV_ITEM_KEY;
1103 key.offset = device->devid;
7d9eb12c 1104 lock_chunks(root);
a061fc8d
CM		 1105
1106 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1107 if (ret < 0)
1108 goto out;
1109
1110 if (ret > 0) {
1111 ret = -ENOENT;
1112 goto out;
1113 }
1114
1115 ret = btrfs_del_item(trans, root, path);
1116 if (ret)
1117 goto out;
a061fc8d
CM		 1118out:
1119 btrfs_free_path(path);
7d9eb12c 1120 unlock_chunks(root);
a061fc8d
CM		 1121 btrfs_commit_transaction(trans, root);
1122 return ret;
1123}
1124
1125int btrfs_rm_device(struct btrfs_root *root, char *device_path)
1126{
1127 struct btrfs_device *device;
2b82032c 1128 struct btrfs_device *next_device;
a061fc8d 1129 struct block_device *bdev;
dfe25020 1130 struct buffer_head *bh = NULL;
a061fc8d
CM		 1131 struct btrfs_super_block *disk_super;
1132 u64 all_avail;
1133 u64 devid;
2b82032c
YZ		 1134 u64 num_devices;
1135 u8 *dev_uuid;
a061fc8d
CM		 1136 int ret = 0;
1137
a061fc8d 1138 mutex_lock(&uuid_mutex);
7d9eb12c 1139 mutex_lock(&root->fs_info->volume_mutex);
a061fc8d
CM		 1140
1141 all_avail = root->fs_info->avail_data_alloc_bits |
1142 root->fs_info->avail_system_alloc_bits |
1143 root->fs_info->avail_metadata_alloc_bits;
1144
1145 if ((all_avail & BTRFS_BLOCK_GROUP_RAID10) &&
035fe03a 1146 root->fs_info->fs_devices->num_devices <= 4) {
d397712b
CM		 1147 printk(KERN_ERR "btrfs: unable to go below four devices "
1148 "on raid10\n");
a061fc8d
CM		 1149 ret = -EINVAL;
1150 goto out;
1151 }
1152
1153 if ((all_avail & BTRFS_BLOCK_GROUP_RAID1) &&
035fe03a 1154 root->fs_info->fs_devices->num_devices <= 2) {
d397712b
CM		 1155 printk(KERN_ERR "btrfs: unable to go below two "
1156 "devices on raid1\n");
a061fc8d
CM		 1157 ret = -EINVAL;
1158 goto out;
1159 }
1160
dfe25020 1161 if (strcmp(device_path, "missing") == 0) {
dfe25020
CM		 1162 struct list_head *devices;
1163 struct btrfs_device *tmp;
a061fc8d 1164
dfe25020
CM		 1165 device = NULL;
1166 devices = &root->fs_info->fs_devices->devices;
e5e9a520 1167 mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
c6e30871 1168 list_for_each_entry(tmp, devices, dev_list) {
dfe25020
CM		 1169 if (tmp->in_fs_metadata && !tmp->bdev) {
1170 device = tmp;
1171 break;
1172 }
1173 }
e5e9a520 1174 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
dfe25020
CM		 1175 bdev = NULL;
1176 bh = NULL;
1177 disk_super = NULL;
1178 if (!device) {
d397712b
CM		 1179 printk(KERN_ERR "btrfs: no missing devices found to "
1180 "remove\n");
dfe25020
CM		 1181 goto out;
1182 }
dfe25020 1183 } else {
97288f2c 1184 bdev = open_bdev_exclusive(device_path, FMODE_READ,
dfe25020
CM		 1185 root->fs_info->bdev_holder);
1186 if (IS_ERR(bdev)) {
1187 ret = PTR_ERR(bdev);
1188 goto out;
1189 }
a061fc8d 1190
2b82032c 1191 set_blocksize(bdev, 4096);
a512bbf8 1192 bh = btrfs_read_dev_super(bdev);
dfe25020
CM		 1193 if (!bh) {
1194 ret = -EIO;
1195 goto error_close;
1196 }
1197 disk_super = (struct btrfs_super_block *)bh->b_data;
a343832f 1198 devid = btrfs_stack_device_id(&disk_super->dev_item);
2b82032c
YZ		 1199 dev_uuid = disk_super->dev_item.uuid;
1200 device = btrfs_find_device(root, devid, dev_uuid,
1201 disk_super->fsid);
dfe25020
CM		 1202 if (!device) {
1203 ret = -ENOENT;
1204 goto error_brelse;
1205 }
2b82032c 1206 }
dfe25020 1207
2b82032c 1208 if (device->writeable && root->fs_info->fs_devices->rw_devices == 1) {
d397712b
CM		 1209 printk(KERN_ERR "btrfs: unable to remove the only writeable "
1210 "device\n");
2b82032c
YZ		 1211 ret = -EINVAL;
1212 goto error_brelse;
1213 }
1214
1215 if (device->writeable) {
1216 list_del_init(&device->dev_alloc_list);
1217 root->fs_info->fs_devices->rw_devices--;
dfe25020 1218 }
a061fc8d
CM		 1219
1220 ret = btrfs_shrink_device(device, 0);
1221 if (ret)
1222 goto error_brelse;
1223
a061fc8d
CM		 1224 ret = btrfs_rm_dev_item(root->fs_info->chunk_root, device);
1225 if (ret)
1226 goto error_brelse;
1227
2b82032c 1228 device->in_fs_metadata = 0;
e5e9a520
CM		 1229
1230 /*
1231 * the device list mutex makes sure that we don't change
1232 * the device list while someone else is writing out all
1233 * the device supers.
1234 */
1235 mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
e4404d6e 1236 list_del_init(&device->dev_list);
e5e9a520
CM		 1237 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
1238
e4404d6e 1239 device->fs_devices->num_devices--;
2b82032c
YZ		 1240
1241 next_device = list_entry(root->fs_info->fs_devices->devices.next,
1242 struct btrfs_device, dev_list);
1243 if (device->bdev == root->fs_info->sb->s_bdev)
1244 root->fs_info->sb->s_bdev = next_device->bdev;
1245 if (device->bdev == root->fs_info->fs_devices->latest_bdev)
1246 root->fs_info->fs_devices->latest_bdev = next_device->bdev;
1247
e4404d6e
YZ		 1248 if (device->bdev) {
1249 close_bdev_exclusive(device->bdev, device->mode);
1250 device->bdev = NULL;
1251 device->fs_devices->open_devices--;
1252 }
1253
2b82032c
YZ		 1254 num_devices = btrfs_super_num_devices(&root->fs_info->super_copy) - 1;
1255 btrfs_set_super_num_devices(&root->fs_info->super_copy, num_devices);
1256
e4404d6e
YZ		 1257 if (device->fs_devices->open_devices == 0) {
1258 struct btrfs_fs_devices *fs_devices;
1259 fs_devices = root->fs_info->fs_devices;
1260 while (fs_devices) {
1261 if (fs_devices->seed == device->fs_devices)
1262 break;
1263 fs_devices = fs_devices->seed;
2b82032c 1264 }
e4404d6e
YZ		 1265 fs_devices->seed = device->fs_devices->seed;
1266 device->fs_devices->seed = NULL;
1267 __btrfs_close_devices(device->fs_devices);
1268 free_fs_devices(device->fs_devices);
2b82032c
YZ		 1269 }
1270
1271 /*
1272 * at this point, the device is zero sized. We want to
1273 * remove it from the devices list and zero out the old super
1274 */
1275 if (device->writeable) {
dfe25020
CM		 1276 /* make sure this device isn't detected as part of
1277 * the FS anymore
1278 */
1279 memset(&disk_super->magic, 0, sizeof(disk_super->magic));
1280 set_buffer_dirty(bh);
1281 sync_dirty_buffer(bh);
dfe25020 1282 }
a061fc8d
CM		 1283
1284 kfree(device->name);
1285 kfree(device);
1286 ret = 0;
a061fc8d
CM		 1287
1288error_brelse:
1289 brelse(bh);
1290error_close:
dfe25020 1291 if (bdev)
97288f2c 1292 close_bdev_exclusive(bdev, FMODE_READ);
a061fc8d 1293out:
7d9eb12c 1294 mutex_unlock(&root->fs_info->volume_mutex);
a061fc8d 1295 mutex_unlock(&uuid_mutex);
a061fc8d
CM		 1296 return ret;
1297}
1298
2b82032c
YZ		 1299/*
1300 * does all the dirty work required for changing file system's UUID.
1301 */
1302static int btrfs_prepare_sprout(struct btrfs_trans_handle *trans,
1303 struct btrfs_root *root)
1304{
1305 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
1306 struct btrfs_fs_devices *old_devices;
e4404d6e 1307 struct btrfs_fs_devices *seed_devices;
2b82032c
YZ		 1308 struct btrfs_super_block *disk_super = &root->fs_info->super_copy;
1309 struct btrfs_device *device;
1310 u64 super_flags;
1311
1312 BUG_ON(!mutex_is_locked(&uuid_mutex));
e4404d6e 1313 if (!fs_devices->seeding)
2b82032c
YZ		 1314 return -EINVAL;
1315
e4404d6e
YZ		 1316 seed_devices = kzalloc(sizeof(*fs_devices), GFP_NOFS);
1317 if (!seed_devices)
2b82032c
YZ		 1318 return -ENOMEM;
1319
e4404d6e
YZ		 1320 old_devices = clone_fs_devices(fs_devices);
1321 if (IS_ERR(old_devices)) {
1322 kfree(seed_devices);
1323 return PTR_ERR(old_devices);
2b82032c 1324 }
e4404d6e 1325
2b82032c
YZ		 1326 list_add(&old_devices->list, &fs_uuids);
1327
e4404d6e
YZ		 1328 memcpy(seed_devices, fs_devices, sizeof(*seed_devices));
1329 seed_devices->opened = 1;
1330 INIT_LIST_HEAD(&seed_devices->devices);
1331 INIT_LIST_HEAD(&seed_devices->alloc_list);
e5e9a520 1332 mutex_init(&seed_devices->device_list_mutex);
e4404d6e
YZ		 1333 list_splice_init(&fs_devices->devices, &seed_devices->devices);
1334 list_splice_init(&fs_devices->alloc_list, &seed_devices->alloc_list);
1335 list_for_each_entry(device, &seed_devices->devices, dev_list) {
1336 device->fs_devices = seed_devices;
1337 }
1338
2b82032c
YZ		 1339 fs_devices->seeding = 0;
1340 fs_devices->num_devices = 0;
1341 fs_devices->open_devices = 0;
e4404d6e 1342 fs_devices->seed = seed_devices;
2b82032c
YZ		 1343
1344 generate_random_uuid(fs_devices->fsid);
1345 memcpy(root->fs_info->fsid, fs_devices->fsid, BTRFS_FSID_SIZE);
1346 memcpy(disk_super->fsid, fs_devices->fsid, BTRFS_FSID_SIZE);
1347 super_flags = btrfs_super_flags(disk_super) &
1348 ~BTRFS_SUPER_FLAG_SEEDING;
1349 btrfs_set_super_flags(disk_super, super_flags);
1350
1351 return 0;
1352}
1353
1354/*
1355 * strore the expected generation for seed devices in device items.
1356 */
1357static int btrfs_finish_sprout(struct btrfs_trans_handle *trans,
1358 struct btrfs_root *root)
1359{
1360 struct btrfs_path *path;
1361 struct extent_buffer *leaf;
1362 struct btrfs_dev_item *dev_item;
1363 struct btrfs_device *device;
1364 struct btrfs_key key;
1365 u8 fs_uuid[BTRFS_UUID_SIZE];
1366 u8 dev_uuid[BTRFS_UUID_SIZE];
1367 u64 devid;
1368 int ret;
1369
1370 path = btrfs_alloc_path();
1371 if (!path)
1372 return -ENOMEM;
1373
1374 root = root->fs_info->chunk_root;
1375 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
1376 key.offset = 0;
1377 key.type = BTRFS_DEV_ITEM_KEY;
1378
1379 while (1) {
1380 ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
1381 if (ret < 0)
1382 goto error;
1383
1384 leaf = path->nodes[0];
1385next_slot:
1386 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
1387 ret = btrfs_next_leaf(root, path);
1388 if (ret > 0)
1389 break;
1390 if (ret < 0)
1391 goto error;
1392 leaf = path->nodes[0];
1393 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
1394 btrfs_release_path(root, path);
1395 continue;
1396 }
1397
1398 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
1399 if (key.objectid != BTRFS_DEV_ITEMS_OBJECTID ||
1400 key.type != BTRFS_DEV_ITEM_KEY)
1401 break;
1402
1403 dev_item = btrfs_item_ptr(leaf, path->slots[0],
1404 struct btrfs_dev_item);
1405 devid = btrfs_device_id(leaf, dev_item);
1406 read_extent_buffer(leaf, dev_uuid,
1407 (unsigned long)btrfs_device_uuid(dev_item),
1408 BTRFS_UUID_SIZE);
1409 read_extent_buffer(leaf, fs_uuid,
1410 (unsigned long)btrfs_device_fsid(dev_item),
1411 BTRFS_UUID_SIZE);
1412 device = btrfs_find_device(root, devid, dev_uuid, fs_uuid);
1413 BUG_ON(!device);
1414
1415 if (device->fs_devices->seeding) {
1416 btrfs_set_device_generation(leaf, dev_item,
1417 device->generation);
1418 btrfs_mark_buffer_dirty(leaf);
1419 }
1420
1421 path->slots[0]++;
1422 goto next_slot;
1423 }
1424 ret = 0;
1425error:
1426 btrfs_free_path(path);
1427 return ret;
1428}
1429
788f20eb
CM		 1430int btrfs_init_new_device(struct btrfs_root *root, char *device_path)
1431{
1432 struct btrfs_trans_handle *trans;
1433 struct btrfs_device *device;
1434 struct block_device *bdev;
788f20eb 1435 struct list_head *devices;
2b82032c 1436 struct super_block *sb = root->fs_info->sb;
788f20eb 1437 u64 total_bytes;
2b82032c 1438 int seeding_dev = 0;
788f20eb
CM		 1439 int ret = 0;
1440
2b82032c
YZ		 1441 if ((sb->s_flags & MS_RDONLY) && !root->fs_info->fs_devices->seeding)
1442 return -EINVAL;
788f20eb 1443
15916de8 1444 bdev = open_bdev_exclusive(device_path, 0, root->fs_info->bdev_holder);
7f59203a
JB		 1445 if (IS_ERR(bdev))
1446 return PTR_ERR(bdev);
a2135011 1447
2b82032c
YZ		 1448 if (root->fs_info->fs_devices->seeding) {
1449 seeding_dev = 1;
1450 down_write(&sb->s_umount);
1451 mutex_lock(&uuid_mutex);
1452 }
1453
8c8bee1d 1454 filemap_write_and_wait(bdev->bd_inode->i_mapping);
7d9eb12c 1455 mutex_lock(&root->fs_info->volume_mutex);
a2135011 1456
788f20eb 1457 devices = &root->fs_info->fs_devices->devices;
e5e9a520
CM		 1458 /*
1459 * we have the volume lock, so we don't need the extra
1460 * device list mutex while reading the list here.
1461 */
c6e30871 1462 list_for_each_entry(device, devices, dev_list) {
788f20eb
CM		 1463 if (device->bdev == bdev) {
1464 ret = -EEXIST;
2b82032c 1465 goto error;
788f20eb
CM		 1466 }
1467 }
1468
1469 device = kzalloc(sizeof(*device), GFP_NOFS);
1470 if (!device) {
1471 /* we can safely leave the fs_devices entry around */
1472 ret = -ENOMEM;
2b82032c 1473 goto error;
788f20eb
CM		 1474 }
1475
788f20eb
CM		 1476 device->name = kstrdup(device_path, GFP_NOFS);
1477 if (!device->name) {
1478 kfree(device);
2b82032c
YZ		 1479 ret = -ENOMEM;
1480 goto error;
788f20eb 1481 }
2b82032c
YZ		 1482
1483 ret = find_next_devid(root, &device->devid);
1484 if (ret) {
1485 kfree(device);
1486 goto error;
1487 }
1488
1489 trans = btrfs_start_transaction(root, 1);
1490 lock_chunks(root);
1491
1492 device->barriers = 1;
1493 device->writeable = 1;
1494 device->work.func = pending_bios_fn;
1495 generate_random_uuid(device->uuid);
1496 spin_lock_init(&device->io_lock);
1497 device->generation = trans->transid;
788f20eb
CM		 1498 device->io_width = root->sectorsize;
1499 device->io_align = root->sectorsize;
1500 device->sector_size = root->sectorsize;
1501 device->total_bytes = i_size_read(bdev->bd_inode);
2cc3c559 1502 device->disk_total_bytes = device->total_bytes;
788f20eb
CM		 1503 device->dev_root = root->fs_info->dev_root;
1504 device->bdev = bdev;
dfe25020 1505 device->in_fs_metadata = 1;
15916de8 1506 device->mode = 0;
2b82032c 1507 set_blocksize(device->bdev, 4096);
788f20eb 1508
2b82032c
YZ		 1509 if (seeding_dev) {
1510 sb->s_flags &= ~MS_RDONLY;
1511 ret = btrfs_prepare_sprout(trans, root);
1512 BUG_ON(ret);
1513 }
788f20eb 1514
2b82032c 1515 device->fs_devices = root->fs_info->fs_devices;
e5e9a520
CM		 1516
1517 /*
1518 * we don't want write_supers to jump in here with our device
1519 * half setup
1520 */
1521 mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
2b82032c
YZ		 1522 list_add(&device->dev_list, &root->fs_info->fs_devices->devices);
1523 list_add(&device->dev_alloc_list,
1524 &root->fs_info->fs_devices->alloc_list);
1525 root->fs_info->fs_devices->num_devices++;
1526 root->fs_info->fs_devices->open_devices++;
1527 root->fs_info->fs_devices->rw_devices++;
1528 root->fs_info->fs_devices->total_rw_bytes += device->total_bytes;
325cd4ba 1529
c289811c
CM		 1530 if (!blk_queue_nonrot(bdev_get_queue(bdev)))
1531 root->fs_info->fs_devices->rotating = 1;
1532
788f20eb
CM		 1533 total_bytes = btrfs_super_total_bytes(&root->fs_info->super_copy);
1534 btrfs_set_super_total_bytes(&root->fs_info->super_copy,
1535 total_bytes + device->total_bytes);
1536
1537 total_bytes = btrfs_super_num_devices(&root->fs_info->super_copy);
1538 btrfs_set_super_num_devices(&root->fs_info->super_copy,
1539 total_bytes + 1);
e5e9a520 1540 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
788f20eb 1541
2b82032c
YZ		 1542 if (seeding_dev) {
1543 ret = init_first_rw_device(trans, root, device);
1544 BUG_ON(ret);
1545 ret = btrfs_finish_sprout(trans, root);
1546 BUG_ON(ret);
1547 } else {
1548 ret = btrfs_add_device(trans, root, device);
1549 }
1550
913d952e
CM		 1551 /*
1552 * we've got more storage, clear any full flags on the space
1553 * infos
1554 */
1555 btrfs_clear_space_info_full(root->fs_info);
1556
7d9eb12c 1557 unlock_chunks(root);
2b82032c 1558 btrfs_commit_transaction(trans, root);
a2135011 1559
2b82032c
YZ		 1560 if (seeding_dev) {
1561 mutex_unlock(&uuid_mutex);
1562 up_write(&sb->s_umount);
788f20eb 1563
2b82032c
YZ		 1564 ret = btrfs_relocate_sys_chunks(root);
1565 BUG_ON(ret);
1566 }
1567out:
1568 mutex_unlock(&root->fs_info->volume_mutex);
1569 return ret;
1570error:
15916de8 1571 close_bdev_exclusive(bdev, 0);
2b82032c
YZ		 1572 if (seeding_dev) {
1573 mutex_unlock(&uuid_mutex);
1574 up_write(&sb->s_umount);
1575 }
788f20eb
CM		 1576 goto out;
1577}
1578
d397712b
CM		 1579static noinline int btrfs_update_device(struct btrfs_trans_handle *trans,
1580 struct btrfs_device *device)
0b86a832
CM		 1581{
1582 int ret;
1583 struct btrfs_path *path;
1584 struct btrfs_root *root;
1585 struct btrfs_dev_item *dev_item;
1586 struct extent_buffer *leaf;
1587 struct btrfs_key key;
1588
1589 root = device->dev_root->fs_info->chunk_root;
1590
1591 path = btrfs_alloc_path();
1592 if (!path)
1593 return -ENOMEM;
1594
1595 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
1596 key.type = BTRFS_DEV_ITEM_KEY;
1597 key.offset = device->devid;
1598
1599 ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
1600 if (ret < 0)
1601 goto out;
1602
1603 if (ret > 0) {
1604 ret = -ENOENT;
1605 goto out;
1606 }
1607
1608 leaf = path->nodes[0];
1609 dev_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dev_item);
1610
1611 btrfs_set_device_id(leaf, dev_item, device->devid);
1612 btrfs_set_device_type(leaf, dev_item, device->type);
1613 btrfs_set_device_io_align(leaf, dev_item, device->io_align);
1614 btrfs_set_device_io_width(leaf, dev_item, device->io_width);
1615 btrfs_set_device_sector_size(leaf, dev_item, device->sector_size);
d6397bae 1616 btrfs_set_device_total_bytes(leaf, dev_item, device->disk_total_bytes);
0b86a832
CM		 1617 btrfs_set_device_bytes_used(leaf, dev_item, device->bytes_used);
1618 btrfs_mark_buffer_dirty(leaf);
1619
1620out:
1621 btrfs_free_path(path);
1622 return ret;
1623}
1624
7d9eb12c 1625static int __btrfs_grow_device(struct btrfs_trans_handle *trans,
8f18cf13
CM		 1626 struct btrfs_device *device, u64 new_size)
1627{
1628 struct btrfs_super_block *super_copy =
1629 &device->dev_root->fs_info->super_copy;
1630 u64 old_total = btrfs_super_total_bytes(super_copy);
1631 u64 diff = new_size - device->total_bytes;
1632
2b82032c
YZ		 1633 if (!device->writeable)
1634 return -EACCES;
1635 if (new_size <= device->total_bytes)
1636 return -EINVAL;
1637
8f18cf13 1638 btrfs_set_super_total_bytes(super_copy, old_total + diff);
2b82032c
YZ		 1639 device->fs_devices->total_rw_bytes += diff;
1640
1641 device->total_bytes = new_size;
9779b72f 1642 device->disk_total_bytes = new_size;
4184ea7f
CM		 1643 btrfs_clear_space_info_full(device->dev_root->fs_info);
1644
8f18cf13
CM		 1645 return btrfs_update_device(trans, device);
1646}
1647
7d9eb12c
CM		 1648int btrfs_grow_device(struct btrfs_trans_handle *trans,
1649 struct btrfs_device *device, u64 new_size)
1650{
1651 int ret;
1652 lock_chunks(device->dev_root);
1653 ret = __btrfs_grow_device(trans, device, new_size);
1654 unlock_chunks(device->dev_root);
1655 return ret;
1656}
1657
8f18cf13
CM		 1658static int btrfs_free_chunk(struct btrfs_trans_handle *trans,
1659 struct btrfs_root *root,
1660 u64 chunk_tree, u64 chunk_objectid,
1661 u64 chunk_offset)
1662{
1663 int ret;
1664 struct btrfs_path *path;
1665 struct btrfs_key key;
1666
1667 root = root->fs_info->chunk_root;
1668 path = btrfs_alloc_path();
1669 if (!path)
1670 return -ENOMEM;
1671
1672 key.objectid = chunk_objectid;
1673 key.offset = chunk_offset;
1674 key.type = BTRFS_CHUNK_ITEM_KEY;
1675
1676 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1677 BUG_ON(ret);
1678
1679 ret = btrfs_del_item(trans, root, path);
1680 BUG_ON(ret);
1681
1682 btrfs_free_path(path);
1683 return 0;
1684}
1685
b2950863 1686static int btrfs_del_sys_chunk(struct btrfs_root *root, u64 chunk_objectid, u64
8f18cf13
CM		 1687 chunk_offset)
1688{
1689 struct btrfs_super_block *super_copy = &root->fs_info->super_copy;
1690 struct btrfs_disk_key *disk_key;
1691 struct btrfs_chunk *chunk;
1692 u8 *ptr;
1693 int ret = 0;
1694 u32 num_stripes;
1695 u32 array_size;
1696 u32 len = 0;
1697 u32 cur;
1698 struct btrfs_key key;
1699
1700 array_size = btrfs_super_sys_array_size(super_copy);
1701
1702 ptr = super_copy->sys_chunk_array;
1703 cur = 0;
1704
1705 while (cur < array_size) {
1706 disk_key = (struct btrfs_disk_key *)ptr;
1707 btrfs_disk_key_to_cpu(&key, disk_key);
1708
1709 len = sizeof(*disk_key);
1710
1711 if (key.type == BTRFS_CHUNK_ITEM_KEY) {
1712 chunk = (struct btrfs_chunk *)(ptr + len);
1713 num_stripes = btrfs_stack_chunk_num_stripes(chunk);
1714 len += btrfs_chunk_item_size(num_stripes);
1715 } else {
1716 ret = -EIO;
1717 break;
1718 }
1719 if (key.objectid == chunk_objectid &&
1720 key.offset == chunk_offset) {
1721 memmove(ptr, ptr + len, array_size - (cur + len));
1722 array_size -= len;
1723 btrfs_set_super_sys_array_size(super_copy, array_size);
1724 } else {
1725 ptr += len;
1726 cur += len;
1727 }
1728 }
1729 return ret;
1730}
1731
b2950863 1732static int btrfs_relocate_chunk(struct btrfs_root *root,
8f18cf13
CM		 1733 u64 chunk_tree, u64 chunk_objectid,
1734 u64 chunk_offset)
1735{
1736 struct extent_map_tree *em_tree;
1737 struct btrfs_root *extent_root;
1738 struct btrfs_trans_handle *trans;
1739 struct extent_map *em;
1740 struct map_lookup *map;
1741 int ret;
1742 int i;
1743
1744 root = root->fs_info->chunk_root;
1745 extent_root = root->fs_info->extent_root;
1746 em_tree = &root->fs_info->mapping_tree.map_tree;
1747
ba1bf481
JB		 1748 ret = btrfs_can_relocate(extent_root, chunk_offset);
1749 if (ret)
1750 return -ENOSPC;
1751
8f18cf13 1752 /* step one, relocate all the extents inside this chunk */
1a40e23b 1753 ret = btrfs_relocate_block_group(extent_root, chunk_offset);
8f18cf13
CM		 1754 BUG_ON(ret);
1755
1756 trans = btrfs_start_transaction(root, 1);
1757 BUG_ON(!trans);
1758
7d9eb12c
CM		 1759 lock_chunks(root);
1760
8f18cf13
CM		 1761 /*
1762 * step two, delete the device extents and the
1763 * chunk tree entries
1764 */
890871be 1765 read_lock(&em_tree->lock);
8f18cf13 1766 em = lookup_extent_mapping(em_tree, chunk_offset, 1);
890871be 1767 read_unlock(&em_tree->lock);
8f18cf13 1768
a061fc8d
CM		 1769 BUG_ON(em->start > chunk_offset ||
1770 em->start + em->len < chunk_offset);
8f18cf13
CM		 1771 map = (struct map_lookup *)em->bdev;
1772
1773 for (i = 0; i < map->num_stripes; i++) {
1774 ret = btrfs_free_dev_extent(trans, map->stripes[i].dev,
1775 map->stripes[i].physical);
1776 BUG_ON(ret);
a061fc8d 1777
dfe25020
CM		 1778 if (map->stripes[i].dev) {
1779 ret = btrfs_update_device(trans, map->stripes[i].dev);
1780 BUG_ON(ret);
1781 }
8f18cf13
CM		 1782 }
1783 ret = btrfs_free_chunk(trans, root, chunk_tree, chunk_objectid,
1784 chunk_offset);
1785
1786 BUG_ON(ret);
1787
1788 if (map->type & BTRFS_BLOCK_GROUP_SYSTEM) {
1789 ret = btrfs_del_sys_chunk(root, chunk_objectid, chunk_offset);
1790 BUG_ON(ret);
8f18cf13
CM		 1791 }
1792
2b82032c
YZ		 1793 ret = btrfs_remove_block_group(trans, extent_root, chunk_offset);
1794 BUG_ON(ret);
1795
890871be 1796 write_lock(&em_tree->lock);
2b82032c 1797 remove_extent_mapping(em_tree, em);
890871be 1798 write_unlock(&em_tree->lock);
2b82032c
YZ		 1799
1800 kfree(map);
1801 em->bdev = NULL;
1802
1803 /* once for the tree */
1804 free_extent_map(em);
1805 /* once for us */
1806 free_extent_map(em);
1807
1808 unlock_chunks(root);
1809 btrfs_end_transaction(trans, root);
1810 return 0;
1811}
1812
1813static int btrfs_relocate_sys_chunks(struct btrfs_root *root)
1814{
1815 struct btrfs_root *chunk_root = root->fs_info->chunk_root;
1816 struct btrfs_path *path;
1817 struct extent_buffer *leaf;
1818 struct btrfs_chunk *chunk;
1819 struct btrfs_key key;
1820 struct btrfs_key found_key;
1821 u64 chunk_tree = chunk_root->root_key.objectid;
1822 u64 chunk_type;
ba1bf481
JB		 1823 bool retried = false;
1824 int failed = 0;
2b82032c
YZ		 1825 int ret;
1826
1827 path = btrfs_alloc_path();
1828 if (!path)
1829 return -ENOMEM;
1830
ba1bf481 1831again:
2b82032c
YZ		 1832 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
1833 key.offset = (u64)-1;
1834 key.type = BTRFS_CHUNK_ITEM_KEY;
1835
1836 while (1) {
1837 ret = btrfs_search_slot(NULL, chunk_root, &key, path, 0, 0);
1838 if (ret < 0)
1839 goto error;
1840 BUG_ON(ret == 0);
1841
1842 ret = btrfs_previous_item(chunk_root, path, key.objectid,
1843 key.type);
1844 if (ret < 0)
1845 goto error;
1846 if (ret > 0)
1847 break;
1a40e23b 1848
2b82032c
YZ		 1849 leaf = path->nodes[0];
1850 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
1a40e23b 1851
2b82032c
YZ		 1852 chunk = btrfs_item_ptr(leaf, path->slots[0],
1853 struct btrfs_chunk);
1854 chunk_type = btrfs_chunk_type(leaf, chunk);
1855 btrfs_release_path(chunk_root, path);
8f18cf13 1856
2b82032c
YZ		 1857 if (chunk_type & BTRFS_BLOCK_GROUP_SYSTEM) {
1858 ret = btrfs_relocate_chunk(chunk_root, chunk_tree,
1859 found_key.objectid,
1860 found_key.offset);
ba1bf481
JB		 1861 if (ret == -ENOSPC)
1862 failed++;
1863 else if (ret)
1864 BUG();
2b82032c 1865 }
8f18cf13 1866
2b82032c
YZ		 1867 if (found_key.offset == 0)
1868 break;
1869 key.offset = found_key.offset - 1;
1870 }
1871 ret = 0;
ba1bf481
JB		 1872 if (failed && !retried) {
1873 failed = 0;
1874 retried = true;
1875 goto again;
1876 } else if (failed && retried) {
1877 WARN_ON(1);
1878 ret = -ENOSPC;
1879 }
2b82032c
YZ		 1880error:
1881 btrfs_free_path(path);
1882 return ret;
8f18cf13
CM		 1883}
1884
ec44a35c
CM		 1885static u64 div_factor(u64 num, int factor)
1886{
1887 if (factor == 10)
1888 return num;
1889 num *= factor;
1890 do_div(num, 10);
1891 return num;
1892}
1893
ec44a35c
CM		 1894int btrfs_balance(struct btrfs_root *dev_root)
1895{
1896 int ret;
ec44a35c
CM		 1897 struct list_head *devices = &dev_root->fs_info->fs_devices->devices;
1898 struct btrfs_device *device;
1899 u64 old_size;
1900 u64 size_to_free;
1901 struct btrfs_path *path;
1902 struct btrfs_key key;
1903 struct btrfs_chunk *chunk;
1904 struct btrfs_root *chunk_root = dev_root->fs_info->chunk_root;
1905 struct btrfs_trans_handle *trans;
1906 struct btrfs_key found_key;
1907
2b82032c
YZ		 1908 if (dev_root->fs_info->sb->s_flags & MS_RDONLY)
1909 return -EROFS;
ec44a35c 1910
7d9eb12c 1911 mutex_lock(&dev_root->fs_info->volume_mutex);
ec44a35c
CM		 1912 dev_root = dev_root->fs_info->dev_root;
1913
ec44a35c 1914 /* step one make some room on all the devices */
c6e30871 1915 list_for_each_entry(device, devices, dev_list) {
ec44a35c
CM		 1916 old_size = device->total_bytes;
1917 size_to_free = div_factor(old_size, 1);
1918 size_to_free = min(size_to_free, (u64)1 * 1024 * 1024);
2b82032c
YZ		 1919 if (!device->writeable ||
1920 device->total_bytes - device->bytes_used > size_to_free)
ec44a35c
CM		 1921 continue;
1922
1923 ret = btrfs_shrink_device(device, old_size - size_to_free);
ba1bf481
JB		 1924 if (ret == -ENOSPC)
1925 break;
ec44a35c
CM		 1926 BUG_ON(ret);
1927
1928 trans = btrfs_start_transaction(dev_root, 1);
1929 BUG_ON(!trans);
1930
1931 ret = btrfs_grow_device(trans, device, old_size);
1932 BUG_ON(ret);
1933
1934 btrfs_end_transaction(trans, dev_root);
1935 }
1936
1937 /* step two, relocate all the chunks */
1938 path = btrfs_alloc_path();
1939 BUG_ON(!path);
1940
1941 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
1942 key.offset = (u64)-1;
1943 key.type = BTRFS_CHUNK_ITEM_KEY;
1944
d397712b 1945 while (1) {
ec44a35c
CM		 1946 ret = btrfs_search_slot(NULL, chunk_root, &key, path, 0, 0);
1947 if (ret < 0)
1948 goto error;
1949
1950 /*
1951 * this shouldn't happen, it means the last relocate
1952 * failed
1953 */
1954 if (ret == 0)
1955 break;
1956
1957 ret = btrfs_previous_item(chunk_root, path, 0,
1958 BTRFS_CHUNK_ITEM_KEY);
7d9eb12c 1959 if (ret)
ec44a35c 1960 break;
7d9eb12c 1961
ec44a35c
CM		 1962 btrfs_item_key_to_cpu(path->nodes[0], &found_key,
1963 path->slots[0]);
1964 if (found_key.objectid != key.objectid)
1965 break;
7d9eb12c 1966
ec44a35c
CM		 1967 chunk = btrfs_item_ptr(path->nodes[0],
1968 path->slots[0],
1969 struct btrfs_chunk);
ec44a35c 1970 /* chunk zero is special */
ba1bf481 1971 if (found_key.offset == 0)
ec44a35c
CM		 1972 break;
1973
7d9eb12c 1974 btrfs_release_path(chunk_root, path);
ec44a35c
CM		 1975 ret = btrfs_relocate_chunk(chunk_root,
1976 chunk_root->root_key.objectid,
1977 found_key.objectid,
1978 found_key.offset);
ba1bf481
JB		 1979 BUG_ON(ret && ret != -ENOSPC);
1980 key.offset = found_key.offset - 1;
ec44a35c
CM		 1981 }
1982 ret = 0;
1983error:
1984 btrfs_free_path(path);
7d9eb12c 1985 mutex_unlock(&dev_root->fs_info->volume_mutex);
ec44a35c
CM		 1986 return ret;
1987}
1988
8f18cf13
CM		 1989/*
1990 * shrinking a device means finding all of the device extents past
1991 * the new size, and then following the back refs to the chunks.
1992 * The chunk relocation code actually frees the device extent
1993 */
1994int btrfs_shrink_device(struct btrfs_device *device, u64 new_size)
1995{
1996 struct btrfs_trans_handle *trans;
1997 struct btrfs_root *root = device->dev_root;
1998 struct btrfs_dev_extent *dev_extent = NULL;
1999 struct btrfs_path *path;
2000 u64 length;
2001 u64 chunk_tree;
2002 u64 chunk_objectid;
2003 u64 chunk_offset;
2004 int ret;
2005 int slot;
ba1bf481
JB		 2006 int failed = 0;
2007 bool retried = false;
8f18cf13
CM		 2008 struct extent_buffer *l;
2009 struct btrfs_key key;
2010 struct btrfs_super_block *super_copy = &root->fs_info->super_copy;
2011 u64 old_total = btrfs_super_total_bytes(super_copy);
ba1bf481 2012 u64 old_size = device->total_bytes;
8f18cf13
CM		 2013 u64 diff = device->total_bytes - new_size;
2014
2b82032c
YZ		 2015 if (new_size >= device->total_bytes)
2016 return -EINVAL;
8f18cf13
CM		 2017
2018 path = btrfs_alloc_path();
2019 if (!path)
2020 return -ENOMEM;
2021
8f18cf13
CM		 2022 path->reada = 2;
2023
7d9eb12c
CM		 2024 lock_chunks(root);
2025
8f18cf13 2026 device->total_bytes = new_size;
2b82032c
YZ		 2027 if (device->writeable)
2028 device->fs_devices->total_rw_bytes -= diff;
7d9eb12c 2029 unlock_chunks(root);
8f18cf13 2030
ba1bf481 2031again:
8f18cf13
CM		 2032 key.objectid = device->devid;
2033 key.offset = (u64)-1;
2034 key.type = BTRFS_DEV_EXTENT_KEY;
2035
2036 while (1) {
2037 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2038 if (ret < 0)
2039 goto done;
2040
2041 ret = btrfs_previous_item(root, path, 0, key.type);
2042 if (ret < 0)
2043 goto done;
2044 if (ret) {
2045 ret = 0;
ba1bf481 2046 btrfs_release_path(root, path);
bf1fb512 2047 break;
8f18cf13
CM		 2048 }
2049
2050 l = path->nodes[0];
2051 slot = path->slots[0];
2052 btrfs_item_key_to_cpu(l, &key, path->slots[0]);
2053
ba1bf481
JB		 2054 if (key.objectid != device->devid) {
2055 btrfs_release_path(root, path);
bf1fb512 2056 break;
ba1bf481 2057 }
8f18cf13
CM		 2058
2059 dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent);
2060 length = btrfs_dev_extent_length(l, dev_extent);
2061
ba1bf481
JB		 2062 if (key.offset + length <= new_size) {
2063 btrfs_release_path(root, path);
d6397bae 2064 break;
ba1bf481 2065 }
8f18cf13
CM		 2066
2067 chunk_tree = btrfs_dev_extent_chunk_tree(l, dev_extent);
2068 chunk_objectid = btrfs_dev_extent_chunk_objectid(l, dev_extent);
2069 chunk_offset = btrfs_dev_extent_chunk_offset(l, dev_extent);
2070 btrfs_release_path(root, path);
2071
2072 ret = btrfs_relocate_chunk(root, chunk_tree, chunk_objectid,
2073 chunk_offset);
ba1bf481 2074 if (ret && ret != -ENOSPC)
8f18cf13 2075 goto done;
ba1bf481
JB		 2076 if (ret == -ENOSPC)
2077 failed++;
2078 key.offset -= 1;
2079 }
2080
2081 if (failed && !retried) {
2082 failed = 0;
2083 retried = true;
2084 goto again;
2085 } else if (failed && retried) {
2086 ret = -ENOSPC;
2087 lock_chunks(root);
2088
2089 device->total_bytes = old_size;
2090 if (device->writeable)
2091 device->fs_devices->total_rw_bytes += diff;
2092 unlock_chunks(root);
2093 goto done;
8f18cf13
CM		 2094 }
2095
d6397bae
CB		 2096 /* Shrinking succeeded, else we would be at "done". */
2097 trans = btrfs_start_transaction(root, 1);
2098 if (!trans) {
2099 ret = -ENOMEM;
2100 goto done;
2101 }
2102 lock_chunks(root);
2103
2104 device->disk_total_bytes = new_size;
2105 /* Now btrfs_update_device() will change the on-disk size. */
2106 ret = btrfs_update_device(trans, device);
2107 if (ret) {
2108 unlock_chunks(root);
2109 btrfs_end_transaction(trans, root);
2110 goto done;
2111 }
2112 WARN_ON(diff > old_total);
2113 btrfs_set_super_total_bytes(super_copy, old_total - diff);
2114 unlock_chunks(root);
2115 btrfs_end_transaction(trans, root);
8f18cf13
CM		 2116done:
2117 btrfs_free_path(path);
2118 return ret;
2119}
2120
b2950863 2121static int btrfs_add_system_chunk(struct btrfs_trans_handle *trans,
0b86a832
CM		 2122 struct btrfs_root *root,
2123 struct btrfs_key *key,
2124 struct btrfs_chunk *chunk, int item_size)
2125{
2126 struct btrfs_super_block *super_copy = &root->fs_info->super_copy;
2127 struct btrfs_disk_key disk_key;
2128 u32 array_size;
2129 u8 *ptr;
2130
2131 array_size = btrfs_super_sys_array_size(super_copy);
2132 if (array_size + item_size > BTRFS_SYSTEM_CHUNK_ARRAY_SIZE)
2133 return -EFBIG;
2134
2135 ptr = super_copy->sys_chunk_array + array_size;
2136 btrfs_cpu_key_to_disk(&disk_key, key);
2137 memcpy(ptr, &disk_key, sizeof(disk_key));
2138 ptr += sizeof(disk_key);
2139 memcpy(ptr, chunk, item_size);
2140 item_size += sizeof(disk_key);
2141 btrfs_set_super_sys_array_size(super_copy, array_size + item_size);
2142 return 0;
2143}
2144
d397712b 2145static noinline u64 chunk_bytes_by_type(u64 type, u64 calc_size,
a1b32a59 2146 int num_stripes, int sub_stripes)
9b3f68b9
CM		 2147{
2148 if (type & (BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_DUP))
2149 return calc_size;
2150 else if (type & BTRFS_BLOCK_GROUP_RAID10)
2151 return calc_size * (num_stripes / sub_stripes);
2152 else
2153 return calc_size * num_stripes;
2154}
2155
2b82032c
YZ		 2156static int __btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
2157 struct btrfs_root *extent_root,
2158 struct map_lookup **map_ret,
2159 u64 *num_bytes, u64 *stripe_size,
2160 u64 start, u64 type)
0b86a832 2161{
593060d7 2162 struct btrfs_fs_info *info = extent_root->fs_info;
0b86a832 2163 struct btrfs_device *device = NULL;
2b82032c 2164 struct btrfs_fs_devices *fs_devices = info->fs_devices;
6324fbf3 2165 struct list_head *cur;
2b82032c 2166 struct map_lookup *map = NULL;
0b86a832 2167 struct extent_map_tree *em_tree;
0b86a832 2168 struct extent_map *em;
2b82032c 2169 struct list_head private_devs;
a40a90a0 2170 int min_stripe_size = 1 * 1024 * 1024;
0b86a832 2171 u64 calc_size = 1024 * 1024 * 1024;
9b3f68b9
CM		 2172 u64 max_chunk_size = calc_size;
2173 u64 min_free;
6324fbf3
CM		 2174 u64 avail;
2175 u64 max_avail = 0;
2b82032c 2176 u64 dev_offset;
6324fbf3 2177 int num_stripes = 1;
a40a90a0 2178 int min_stripes = 1;
321aecc6 2179 int sub_stripes = 0;
6324fbf3 2180 int looped = 0;
0b86a832 2181 int ret;
6324fbf3 2182 int index;
593060d7 2183 int stripe_len = 64 * 1024;
0b86a832 2184
ec44a35c
CM		 2185 if ((type & BTRFS_BLOCK_GROUP_RAID1) &&
2186 (type & BTRFS_BLOCK_GROUP_DUP)) {
2187 WARN_ON(1);
2188 type &= ~BTRFS_BLOCK_GROUP_DUP;
2189 }
2b82032c 2190 if (list_empty(&fs_devices->alloc_list))
6324fbf3 2191 return -ENOSPC;
593060d7 2192
a40a90a0 2193 if (type & (BTRFS_BLOCK_GROUP_RAID0)) {
2b82032c 2194 num_stripes = fs_devices->rw_devices;
a40a90a0
CM		 2195 min_stripes = 2;
2196 }
2197 if (type & (BTRFS_BLOCK_GROUP_DUP)) {
611f0e00 2198 num_stripes = 2;
a40a90a0
CM		 2199 min_stripes = 2;
2200 }
8790d502 2201 if (type & (BTRFS_BLOCK_GROUP_RAID1)) {
f3eae7e8 2202 if (fs_devices->rw_devices < 2)
9b3f68b9 2203 return -ENOSPC;
f3eae7e8 2204 num_stripes = 2;
a40a90a0 2205 min_stripes = 2;
8790d502 2206 }
321aecc6 2207 if (type & (BTRFS_BLOCK_GROUP_RAID10)) {
2b82032c 2208 num_stripes = fs_devices->rw_devices;
321aecc6
CM		 2209 if (num_stripes < 4)
2210 return -ENOSPC;
2211 num_stripes &= ~(u32)1;
2212 sub_stripes = 2;
a40a90a0 2213 min_stripes = 4;
321aecc6 2214 }
9b3f68b9
CM		 2215
2216 if (type & BTRFS_BLOCK_GROUP_DATA) {
2217 max_chunk_size = 10 * calc_size;
a40a90a0 2218 min_stripe_size = 64 * 1024 * 1024;
9b3f68b9 2219 } else if (type & BTRFS_BLOCK_GROUP_METADATA) {
83d3c969 2220 max_chunk_size = 256 * 1024 * 1024;
a40a90a0
CM		 2221 min_stripe_size = 32 * 1024 * 1024;
2222 } else if (type & BTRFS_BLOCK_GROUP_SYSTEM) {
2223 calc_size = 8 * 1024 * 1024;
2224 max_chunk_size = calc_size * 2;
2225 min_stripe_size = 1 * 1024 * 1024;
9b3f68b9
CM		 2226 }
2227
2b82032c
YZ		 2228 /* we don't want a chunk larger than 10% of writeable space */
2229 max_chunk_size = min(div_factor(fs_devices->total_rw_bytes, 1),
2230 max_chunk_size);
9b3f68b9 2231
a40a90a0 2232again:
9779b72f 2233 max_avail = 0;
2b82032c
YZ		 2234 if (!map || map->num_stripes != num_stripes) {
2235 kfree(map);
2236 map = kmalloc(map_lookup_size(num_stripes), GFP_NOFS);
2237 if (!map)
2238 return -ENOMEM;
2239 map->num_stripes = num_stripes;
2240 }
2241
9b3f68b9
CM		 2242 if (calc_size * num_stripes > max_chunk_size) {
2243 calc_size = max_chunk_size;
2244 do_div(calc_size, num_stripes);
2245 do_div(calc_size, stripe_len);
2246 calc_size *= stripe_len;
2247 }
0cad8a11 2248
9b3f68b9 2249 /* we don't want tiny stripes */
0cad8a11
JB		 2250 if (!looped)
2251 calc_size = max_t(u64, min_stripe_size, calc_size);
9b3f68b9 2252
9f680ce0
CM		 2253 /*
2254 * we're about to do_div by the stripe_len so lets make sure
2255 * we end up with something bigger than a stripe
2256 */
2257 calc_size = max_t(u64, calc_size, stripe_len * 4);
2258
9b3f68b9
CM		 2259 do_div(calc_size, stripe_len);
2260 calc_size *= stripe_len;
2261
2b82032c 2262 cur = fs_devices->alloc_list.next;
6324fbf3 2263 index = 0;
611f0e00
CM		 2264
2265 if (type & BTRFS_BLOCK_GROUP_DUP)
2266 min_free = calc_size * 2;
9b3f68b9
CM		 2267 else
2268 min_free = calc_size;
611f0e00 2269
0f9dd46c
JB		 2270 /*
2271 * we add 1MB because we never use the first 1MB of the device, unless
2272 * we've looped, then we are likely allocating the maximum amount of
2273 * space left already
2274 */
2275 if (!looped)
2276 min_free += 1024 * 1024;
ad5bd91e 2277
2b82032c 2278 INIT_LIST_HEAD(&private_devs);
d397712b 2279 while (index < num_stripes) {
b3075717 2280 device = list_entry(cur, struct btrfs_device, dev_alloc_list);
2b82032c 2281 BUG_ON(!device->writeable);
dfe25020
CM		 2282 if (device->total_bytes > device->bytes_used)
2283 avail = device->total_bytes - device->bytes_used;
2284 else
2285 avail = 0;
6324fbf3 2286 cur = cur->next;
8f18cf13 2287
dfe25020 2288 if (device->in_fs_metadata && avail >= min_free) {
2b82032c 2289 ret = find_free_dev_extent(trans, device,
9779b72f
CM		 2290 min_free, &dev_offset,
2291 &max_avail);
8f18cf13
CM		 2292 if (ret == 0) {
2293 list_move_tail(&device->dev_alloc_list,
2294 &private_devs);
2b82032c
YZ		 2295 map->stripes[index].dev = device;
2296 map->stripes[index].physical = dev_offset;
611f0e00 2297 index++;
2b82032c
YZ		 2298 if (type & BTRFS_BLOCK_GROUP_DUP) {
2299 map->stripes[index].dev = device;
2300 map->stripes[index].physical =
2301 dev_offset + calc_size;
8f18cf13 2302 index++;
2b82032c 2303 }
8f18cf13 2304 }
dfe25020 2305 } else if (device->in_fs_metadata && avail > max_avail)
a40a90a0 2306 max_avail = avail;
2b82032c 2307 if (cur == &fs_devices->alloc_list)
6324fbf3
CM		 2308 break;
2309 }
2b82032c 2310 list_splice(&private_devs, &fs_devices->alloc_list);
6324fbf3 2311 if (index < num_stripes) {
a40a90a0
CM		 2312 if (index >= min_stripes) {
2313 num_stripes = index;
2314 if (type & (BTRFS_BLOCK_GROUP_RAID10)) {
2315 num_stripes /= sub_stripes;
2316 num_stripes *= sub_stripes;
2317 }
2318 looped = 1;
2319 goto again;
2320 }
6324fbf3
CM		 2321 if (!looped && max_avail > 0) {
2322 looped = 1;
2323 calc_size = max_avail;
2324 goto again;
2325 }
2b82032c 2326 kfree(map);
6324fbf3
CM		 2327 return -ENOSPC;
2328 }
2b82032c
YZ		 2329 map->sector_size = extent_root->sectorsize;
2330 map->stripe_len = stripe_len;
2331 map->io_align = stripe_len;
2332 map->io_width = stripe_len;
2333 map->type = type;
2334 map->num_stripes = num_stripes;
2335 map->sub_stripes = sub_stripes;
0b86a832 2336
2b82032c
YZ		 2337 *map_ret = map;
2338 *stripe_size = calc_size;
2339 *num_bytes = chunk_bytes_by_type(type, calc_size,
2340 num_stripes, sub_stripes);
0b86a832 2341
2b82032c
YZ		 2342 em = alloc_extent_map(GFP_NOFS);
2343 if (!em) {
2344 kfree(map);
593060d7
CM		 2345 return -ENOMEM;
2346 }
2b82032c
YZ		 2347 em->bdev = (struct block_device *)map;
2348 em->start = start;
2349 em->len = *num_bytes;
2350 em->block_start = 0;
2351 em->block_len = em->len;
593060d7 2352
2b82032c 2353 em_tree = &extent_root->fs_info->mapping_tree.map_tree;
890871be 2354 write_lock(&em_tree->lock);
2b82032c 2355 ret = add_extent_mapping(em_tree, em);
890871be 2356 write_unlock(&em_tree->lock);
2b82032c
YZ		 2357 BUG_ON(ret);
2358 free_extent_map(em);
0b86a832 2359
2b82032c
YZ		 2360 ret = btrfs_make_block_group(trans, extent_root, 0, type,
2361 BTRFS_FIRST_CHUNK_TREE_OBJECTID,
2362 start, *num_bytes);
2363 BUG_ON(ret);
611f0e00 2364
2b82032c
YZ		 2365 index = 0;
2366 while (index < map->num_stripes) {
2367 device = map->stripes[index].dev;
2368 dev_offset = map->stripes[index].physical;
0b86a832
CM		 2369
2370 ret = btrfs_alloc_dev_extent(trans, device,
2b82032c
YZ		 2371 info->chunk_root->root_key.objectid,
2372 BTRFS_FIRST_CHUNK_TREE_OBJECTID,
2373 start, dev_offset, calc_size);
0b86a832 2374 BUG_ON(ret);
2b82032c
YZ		 2375 index++;
2376 }
2377
2378 return 0;
2379}
2380
2381static int __finish_chunk_alloc(struct btrfs_trans_handle *trans,
2382 struct btrfs_root *extent_root,
2383 struct map_lookup *map, u64 chunk_offset,
2384 u64 chunk_size, u64 stripe_size)
2385{
2386 u64 dev_offset;
2387 struct btrfs_key key;
2388 struct btrfs_root *chunk_root = extent_root->fs_info->chunk_root;
2389 struct btrfs_device *device;
2390 struct btrfs_chunk *chunk;
2391 struct btrfs_stripe *stripe;
2392 size_t item_size = btrfs_chunk_item_size(map->num_stripes);
2393 int index = 0;
2394 int ret;
2395
2396 chunk = kzalloc(item_size, GFP_NOFS);
2397 if (!chunk)
2398 return -ENOMEM;
2399
2400 index = 0;
2401 while (index < map->num_stripes) {
2402 device = map->stripes[index].dev;
2403 device->bytes_used += stripe_size;
0b86a832
CM		 2404 ret = btrfs_update_device(trans, device);
2405 BUG_ON(ret);
2b82032c
YZ		 2406 index++;
2407 }
2408
2409 index = 0;
2410 stripe = &chunk->stripe;
2411 while (index < map->num_stripes) {
2412 device = map->stripes[index].dev;
2413 dev_offset = map->stripes[index].physical;
0b86a832 2414
e17cade2
CM		 2415 btrfs_set_stack_stripe_devid(stripe, device->devid);
2416 btrfs_set_stack_stripe_offset(stripe, dev_offset);
2417 memcpy(stripe->dev_uuid, device->uuid, BTRFS_UUID_SIZE);
2b82032c 2418 stripe++;
0b86a832
CM		 2419 index++;
2420 }
2421
2b82032c 2422 btrfs_set_stack_chunk_length(chunk, chunk_size);
0b86a832 2423 btrfs_set_stack_chunk_owner(chunk, extent_root->root_key.objectid);
2b82032c
YZ		 2424 btrfs_set_stack_chunk_stripe_len(chunk, map->stripe_len);
2425 btrfs_set_stack_chunk_type(chunk, map->type);
2426 btrfs_set_stack_chunk_num_stripes(chunk, map->num_stripes);
2427 btrfs_set_stack_chunk_io_align(chunk, map->stripe_len);
2428 btrfs_set_stack_chunk_io_width(chunk, map->stripe_len);
0b86a832 2429 btrfs_set_stack_chunk_sector_size(chunk, extent_root->sectorsize);
2b82032c 2430 btrfs_set_stack_chunk_sub_stripes(chunk, map->sub_stripes);
0b86a832 2431
2b82032c
YZ		 2432 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
2433 key.type = BTRFS_CHUNK_ITEM_KEY;
2434 key.offset = chunk_offset;
0b86a832 2435
2b82032c
YZ		 2436 ret = btrfs_insert_item(trans, chunk_root, &key, chunk, item_size);
2437 BUG_ON(ret);
0b86a832 2438
2b82032c
YZ		 2439 if (map->type & BTRFS_BLOCK_GROUP_SYSTEM) {
2440 ret = btrfs_add_system_chunk(trans, chunk_root, &key, chunk,
2441 item_size);
8f18cf13
CM		 2442 BUG_ON(ret);
2443 }
0b86a832 2444 kfree(chunk);
2b82032c
YZ		 2445 return 0;
2446}
0b86a832 2447
2b82032c
YZ		 2448/*
2449 * Chunk allocation falls into two parts. The first part does works
2450 * that make the new allocated chunk useable, but not do any operation
2451 * that modifies the chunk tree. The second part does the works that
2452 * require modifying the chunk tree. This division is important for the
2453 * bootstrap process of adding storage to a seed btrfs.
2454 */
2455int btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
2456 struct btrfs_root *extent_root, u64 type)
2457{
2458 u64 chunk_offset;
2459 u64 chunk_size;
2460 u64 stripe_size;
2461 struct map_lookup *map;
2462 struct btrfs_root *chunk_root = extent_root->fs_info->chunk_root;
2463 int ret;
2464
2465 ret = find_next_chunk(chunk_root, BTRFS_FIRST_CHUNK_TREE_OBJECTID,
2466 &chunk_offset);
2467 if (ret)
2468 return ret;
2469
2470 ret = __btrfs_alloc_chunk(trans, extent_root, &map, &chunk_size,
2471 &stripe_size, chunk_offset, type);
2472 if (ret)
2473 return ret;
2474
2475 ret = __finish_chunk_alloc(trans, extent_root, map, chunk_offset,
2476 chunk_size, stripe_size);
2477 BUG_ON(ret);
2478 return 0;
2479}
2480
d397712b 2481static noinline int init_first_rw_device(struct btrfs_trans_handle *trans,
2b82032c
YZ		 2482 struct btrfs_root *root,
2483 struct btrfs_device *device)
2484{
2485 u64 chunk_offset;
2486 u64 sys_chunk_offset;
2487 u64 chunk_size;
2488 u64 sys_chunk_size;
2489 u64 stripe_size;
2490 u64 sys_stripe_size;
2491 u64 alloc_profile;
2492 struct map_lookup *map;
2493 struct map_lookup *sys_map;
2494 struct btrfs_fs_info *fs_info = root->fs_info;
2495 struct btrfs_root *extent_root = fs_info->extent_root;
2496 int ret;
2497
2498 ret = find_next_chunk(fs_info->chunk_root,
2499 BTRFS_FIRST_CHUNK_TREE_OBJECTID, &chunk_offset);
2500 BUG_ON(ret);
2501
2502 alloc_profile = BTRFS_BLOCK_GROUP_METADATA |
2503 (fs_info->metadata_alloc_profile &
2504 fs_info->avail_metadata_alloc_bits);
2505 alloc_profile = btrfs_reduce_alloc_profile(root, alloc_profile);
2506
2507 ret = __btrfs_alloc_chunk(trans, extent_root, &map, &chunk_size,
2508 &stripe_size, chunk_offset, alloc_profile);
2509 BUG_ON(ret);
2510
2511 sys_chunk_offset = chunk_offset + chunk_size;
2512
2513 alloc_profile = BTRFS_BLOCK_GROUP_SYSTEM |
2514 (fs_info->system_alloc_profile &
2515 fs_info->avail_system_alloc_bits);
2516 alloc_profile = btrfs_reduce_alloc_profile(root, alloc_profile);
2517
2518 ret = __btrfs_alloc_chunk(trans, extent_root, &sys_map,
2519 &sys_chunk_size, &sys_stripe_size,
2520 sys_chunk_offset, alloc_profile);
2521 BUG_ON(ret);
2522
2523 ret = btrfs_add_device(trans, fs_info->chunk_root, device);
2524 BUG_ON(ret);
2525
2526 /*
2527 * Modifying chunk tree needs allocating new blocks from both
2528 * system block group and metadata block group. So we only can
2529 * do operations require modifying the chunk tree after both
2530 * block groups were created.
2531 */
2532 ret = __finish_chunk_alloc(trans, extent_root, map, chunk_offset,
2533 chunk_size, stripe_size);
2534 BUG_ON(ret);
2535
2536 ret = __finish_chunk_alloc(trans, extent_root, sys_map,
2537 sys_chunk_offset, sys_chunk_size,
2538 sys_stripe_size);
b248a415 2539 BUG_ON(ret);
2b82032c
YZ		 2540 return 0;
2541}
2542
2543int btrfs_chunk_readonly(struct btrfs_root *root, u64 chunk_offset)
2544{
2545 struct extent_map *em;
2546 struct map_lookup *map;
2547 struct btrfs_mapping_tree *map_tree = &root->fs_info->mapping_tree;
2548 int readonly = 0;
2549 int i;
2550
890871be 2551 read_lock(&map_tree->map_tree.lock);
2b82032c 2552 em = lookup_extent_mapping(&map_tree->map_tree, chunk_offset, 1);
890871be 2553 read_unlock(&map_tree->map_tree.lock);
2b82032c
YZ		 2554 if (!em)
2555 return 1;
2556
f48b9075
JB		 2557 if (btrfs_test_opt(root, DEGRADED)) {
2558 free_extent_map(em);
2559 return 0;
2560 }
2561
2b82032c
YZ		 2562 map = (struct map_lookup *)em->bdev;
2563 for (i = 0; i < map->num_stripes; i++) {
2564 if (!map->stripes[i].dev->writeable) {
2565 readonly = 1;
2566 break;
2567 }
2568 }
0b86a832 2569 free_extent_map(em);
2b82032c 2570 return readonly;
0b86a832
CM		 2571}
2572
2573void btrfs_mapping_init(struct btrfs_mapping_tree *tree)
2574{
2575 extent_map_tree_init(&tree->map_tree, GFP_NOFS);
2576}
2577
2578void btrfs_mapping_tree_free(struct btrfs_mapping_tree *tree)
2579{
2580 struct extent_map *em;
2581
d397712b 2582 while (1) {
890871be 2583 write_lock(&tree->map_tree.lock);
0b86a832
CM		 2584 em = lookup_extent_mapping(&tree->map_tree, 0, (u64)-1);
2585 if (em)
2586 remove_extent_mapping(&tree->map_tree, em);
890871be 2587 write_unlock(&tree->map_tree.lock);
0b86a832
CM		 2588 if (!em)
2589 break;
2590 kfree(em->bdev);
2591 /* once for us */
2592 free_extent_map(em);
2593 /* once for the tree */
2594 free_extent_map(em);
2595 }
2596}
2597
f188591e
CM		 2598int btrfs_num_copies(struct btrfs_mapping_tree *map_tree, u64 logical, u64 len)
2599{
2600 struct extent_map *em;
2601 struct map_lookup *map;
2602 struct extent_map_tree *em_tree = &map_tree->map_tree;
2603 int ret;
2604
890871be 2605 read_lock(&em_tree->lock);
f188591e 2606 em = lookup_extent_mapping(em_tree, logical, len);
890871be 2607 read_unlock(&em_tree->lock);
f188591e
CM		 2608 BUG_ON(!em);
2609
2610 BUG_ON(em->start > logical || em->start + em->len < logical);
2611 map = (struct map_lookup *)em->bdev;
2612 if (map->type & (BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID1))
2613 ret = map->num_stripes;
321aecc6
CM		 2614 else if (map->type & BTRFS_BLOCK_GROUP_RAID10)
2615 ret = map->sub_stripes;
f188591e
CM		 2616 else
2617 ret = 1;
2618 free_extent_map(em);
f188591e
CM		 2619 return ret;
2620}
2621
dfe25020
CM		 2622static int find_live_mirror(struct map_lookup *map, int first, int num,
2623 int optimal)
2624{
2625 int i;
2626 if (map->stripes[optimal].dev->bdev)
2627 return optimal;
2628 for (i = first; i < first + num; i++) {
2629 if (map->stripes[i].dev->bdev)
2630 return i;
2631 }
2632 /* we couldn't find one that doesn't fail. Just return something
2633 * and the io error handling code will clean up eventually
2634 */
2635 return optimal;
2636}
2637
f2d8d74d
CM		 2638static int __btrfs_map_block(struct btrfs_mapping_tree *map_tree, int rw,
2639 u64 logical, u64 *length,
2640 struct btrfs_multi_bio **multi_ret,
2641 int mirror_num, struct page *unplug_page)
0b86a832
CM		 2642{
2643 struct extent_map *em;
2644 struct map_lookup *map;
2645 struct extent_map_tree *em_tree = &map_tree->map_tree;
2646 u64 offset;
593060d7
CM		 2647 u64 stripe_offset;
2648 u64 stripe_nr;
cea9e445 2649 int stripes_allocated = 8;
321aecc6 2650 int stripes_required = 1;
593060d7 2651 int stripe_index;
cea9e445 2652 int i;
f2d8d74d 2653 int num_stripes;
a236aed1 2654 int max_errors = 0;
cea9e445 2655 struct btrfs_multi_bio *multi = NULL;
0b86a832 2656
d397712b 2657 if (multi_ret && !(rw & (1 << BIO_RW)))
cea9e445 2658 stripes_allocated = 1;
cea9e445
CM		 2659again:
2660 if (multi_ret) {
2661 multi = kzalloc(btrfs_multi_bio_size(stripes_allocated),
2662 GFP_NOFS);
2663 if (!multi)
2664 return -ENOMEM;
a236aed1
CM		 2665
2666 atomic_set(&multi->error, 0);
cea9e445 2667 }
0b86a832 2668
890871be 2669 read_lock(&em_tree->lock);
0b86a832 2670 em = lookup_extent_mapping(em_tree, logical, *length);
890871be 2671 read_unlock(&em_tree->lock);
f2d8d74d 2672
2423fdfb
JS		 2673 if (!em && unplug_page) {
2674 kfree(multi);
f2d8d74d 2675 return 0;
2423fdfb 2676 }
f2d8d74d 2677
3b951516 2678 if (!em) {
d397712b
CM		 2679 printk(KERN_CRIT "unable to find logical %llu len %llu\n",
2680 (unsigned long long)logical,
2681 (unsigned long long)*length);
f2d8d74d 2682 BUG();
3b951516 2683 }
0b86a832
CM		 2684
2685 BUG_ON(em->start > logical || em->start + em->len < logical);
2686 map = (struct map_lookup *)em->bdev;
2687 offset = logical - em->start;
593060d7 2688
f188591e
CM		 2689 if (mirror_num > map->num_stripes)
2690 mirror_num = 0;
2691
cea9e445 2692 /* if our multi bio struct is too small, back off and try again */
321aecc6
CM		 2693 if (rw & (1 << BIO_RW)) {
2694 if (map->type & (BTRFS_BLOCK_GROUP_RAID1 |
2695 BTRFS_BLOCK_GROUP_DUP)) {
2696 stripes_required = map->num_stripes;
a236aed1 2697 max_errors = 1;
321aecc6
CM		 2698 } else if (map->type & BTRFS_BLOCK_GROUP_RAID10) {
2699 stripes_required = map->sub_stripes;
a236aed1 2700 max_errors = 1;
321aecc6
CM		 2701 }
2702 }
ffbd517d 2703 if (multi_ret && (rw & (1 << BIO_RW)) &&
321aecc6 2704 stripes_allocated < stripes_required) {
cea9e445 2705 stripes_allocated = map->num_stripes;
cea9e445
CM		 2706 free_extent_map(em);
2707 kfree(multi);
2708 goto again;
2709 }
593060d7
CM		 2710 stripe_nr = offset;
2711 /*
2712 * stripe_nr counts the total number of stripes we have to stride
2713 * to get to this block
2714 */
2715 do_div(stripe_nr, map->stripe_len);
2716
2717 stripe_offset = stripe_nr * map->stripe_len;
2718 BUG_ON(offset < stripe_offset);
2719
2720 /* stripe_offset is the offset of this block in its stripe*/
2721 stripe_offset = offset - stripe_offset;
2722
cea9e445 2723 if (map->type & (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID1 |
321aecc6 2724 BTRFS_BLOCK_GROUP_RAID10 |
cea9e445
CM		 2725 BTRFS_BLOCK_GROUP_DUP)) {
2726 /* we limit the length of each bio to what fits in a stripe */
2727 *length = min_t(u64, em->len - offset,
2728 map->stripe_len - stripe_offset);
2729 } else {
2730 *length = em->len - offset;
2731 }
f2d8d74d
CM		 2732
2733 if (!multi_ret && !unplug_page)
cea9e445
CM		 2734 goto out;
2735
f2d8d74d 2736 num_stripes = 1;
cea9e445 2737 stripe_index = 0;
8790d502 2738 if (map->type & BTRFS_BLOCK_GROUP_RAID1) {
f2d8d74d
CM		 2739 if (unplug_page || (rw & (1 << BIO_RW)))
2740 num_stripes = map->num_stripes;
2fff734f 2741 else if (mirror_num)
f188591e 2742 stripe_index = mirror_num - 1;
dfe25020
CM		 2743 else {
2744 stripe_index = find_live_mirror(map, 0,
2745 map->num_stripes,
2746 current->pid % map->num_stripes);
2747 }
2fff734f 2748
611f0e00 2749 } else if (map->type & BTRFS_BLOCK_GROUP_DUP) {
cea9e445 2750 if (rw & (1 << BIO_RW))
f2d8d74d 2751 num_stripes = map->num_stripes;
f188591e
CM		 2752 else if (mirror_num)
2753 stripe_index = mirror_num - 1;
2fff734f 2754
321aecc6
CM		 2755 } else if (map->type & BTRFS_BLOCK_GROUP_RAID10) {
2756 int factor = map->num_stripes / map->sub_stripes;
321aecc6
CM		 2757
2758 stripe_index = do_div(stripe_nr, factor);
2759 stripe_index *= map->sub_stripes;
2760
f2d8d74d
CM		 2761 if (unplug_page || (rw & (1 << BIO_RW)))
2762 num_stripes = map->sub_stripes;
321aecc6
CM		 2763 else if (mirror_num)
2764 stripe_index += mirror_num - 1;
dfe25020
CM		 2765 else {
2766 stripe_index = find_live_mirror(map, stripe_index,
2767 map->sub_stripes, stripe_index +
2768 current->pid % map->sub_stripes);
2769 }
8790d502
CM		 2770 } else {
2771 /*
2772 * after this do_div call, stripe_nr is the number of stripes
2773 * on this device we have to walk to find the data, and
2774 * stripe_index is the number of our device in the stripe array
2775 */
2776 stripe_index = do_div(stripe_nr, map->num_stripes);
2777 }
593060d7 2778 BUG_ON(stripe_index >= map->num_stripes);
cea9e445 2779
f2d8d74d
CM		 2780 for (i = 0; i < num_stripes; i++) {
2781 if (unplug_page) {
2782 struct btrfs_device *device;
2783 struct backing_dev_info *bdi;
2784
2785 device = map->stripes[stripe_index].dev;
dfe25020
CM		 2786 if (device->bdev) {
2787 bdi = blk_get_backing_dev_info(device->bdev);
d397712b 2788 if (bdi->unplug_io_fn)
dfe25020 2789 bdi->unplug_io_fn(bdi, unplug_page);
f2d8d74d
CM		 2790 }
2791 } else {
2792 multi->stripes[i].physical =
2793 map->stripes[stripe_index].physical +
2794 stripe_offset + stripe_nr * map->stripe_len;
2795 multi->stripes[i].dev = map->stripes[stripe_index].dev;
2796 }
cea9e445 2797 stripe_index++;
593060d7 2798 }
f2d8d74d
CM		 2799 if (multi_ret) {
2800 *multi_ret = multi;
2801 multi->num_stripes = num_stripes;
a236aed1 2802 multi->max_errors = max_errors;
f2d8d74d 2803 }
cea9e445 2804out:
0b86a832 2805 free_extent_map(em);
0b86a832
CM		 2806 return 0;
2807}
2808
f2d8d74d
CM		 2809int btrfs_map_block(struct btrfs_mapping_tree *map_tree, int rw,
2810 u64 logical, u64 *length,
2811 struct btrfs_multi_bio **multi_ret, int mirror_num)
2812{
2813 return __btrfs_map_block(map_tree, rw, logical, length, multi_ret,
2814 mirror_num, NULL);
2815}
2816
a512bbf8
YZ		 2817int btrfs_rmap_block(struct btrfs_mapping_tree *map_tree,
2818 u64 chunk_start, u64 physical, u64 devid,
2819 u64 **logical, int *naddrs, int *stripe_len)
2820{
2821 struct extent_map_tree *em_tree = &map_tree->map_tree;
2822 struct extent_map *em;
2823 struct map_lookup *map;
2824 u64 *buf;
2825 u64 bytenr;
2826 u64 length;
2827 u64 stripe_nr;
2828 int i, j, nr = 0;
2829
890871be 2830 read_lock(&em_tree->lock);
a512bbf8 2831 em = lookup_extent_mapping(em_tree, chunk_start, 1);
890871be 2832 read_unlock(&em_tree->lock);
a512bbf8
YZ		 2833
2834 BUG_ON(!em || em->start != chunk_start);
2835 map = (struct map_lookup *)em->bdev;
2836
2837 length = em->len;
2838 if (map->type & BTRFS_BLOCK_GROUP_RAID10)
2839 do_div(length, map->num_stripes / map->sub_stripes);
2840 else if (map->type & BTRFS_BLOCK_GROUP_RAID0)
2841 do_div(length, map->num_stripes);
2842
2843 buf = kzalloc(sizeof(u64) * map->num_stripes, GFP_NOFS);
2844 BUG_ON(!buf);
2845
2846 for (i = 0; i < map->num_stripes; i++) {
2847 if (devid && map->stripes[i].dev->devid != devid)
2848 continue;
2849 if (map->stripes[i].physical > physical ||
2850 map->stripes[i].physical + length <= physical)
2851 continue;
2852
2853 stripe_nr = physical - map->stripes[i].physical;
2854 do_div(stripe_nr, map->stripe_len);
2855
2856 if (map->type & BTRFS_BLOCK_GROUP_RAID10) {
2857 stripe_nr = stripe_nr * map->num_stripes + i;
2858 do_div(stripe_nr, map->sub_stripes);
2859 } else if (map->type & BTRFS_BLOCK_GROUP_RAID0) {
2860 stripe_nr = stripe_nr * map->num_stripes + i;
2861 }
2862 bytenr = chunk_start + stripe_nr * map->stripe_len;
934d375b 2863 WARN_ON(nr >= map->num_stripes);
a512bbf8
YZ		 2864 for (j = 0; j < nr; j++) {
2865 if (buf[j] == bytenr)
2866 break;
2867 }
934d375b
CM		 2868 if (j == nr) {
2869 WARN_ON(nr >= map->num_stripes);
a512bbf8 2870 buf[nr++] = bytenr;
934d375b 2871 }
a512bbf8
YZ		 2872 }
2873
a512bbf8
YZ		 2874 *logical = buf;
2875 *naddrs = nr;
2876 *stripe_len = map->stripe_len;
2877
2878 free_extent_map(em);
2879 return 0;
2880}
2881
f2d8d74d
CM		 2882int btrfs_unplug_page(struct btrfs_mapping_tree *map_tree,
2883 u64 logical, struct page *page)
2884{
2885 u64 length = PAGE_CACHE_SIZE;
2886 return __btrfs_map_block(map_tree, READ, logical, &length,
2887 NULL, 0, page);
2888}
2889
8790d502 2890static void end_bio_multi_stripe(struct bio *bio, int err)
8790d502 2891{
cea9e445 2892 struct btrfs_multi_bio *multi = bio->bi_private;
7d2b4daa 2893 int is_orig_bio = 0;
8790d502 2894
8790d502 2895 if (err)
a236aed1 2896 atomic_inc(&multi->error);
8790d502 2897
7d2b4daa
CM		 2898 if (bio == multi->orig_bio)
2899 is_orig_bio = 1;
2900
cea9e445 2901 if (atomic_dec_and_test(&multi->stripes_pending)) {
7d2b4daa
CM		 2902 if (!is_orig_bio) {
2903 bio_put(bio);
2904 bio = multi->orig_bio;
2905 }
8790d502
CM		 2906 bio->bi_private = multi->private;
2907 bio->bi_end_io = multi->end_io;
a236aed1
CM		 2908 /* only send an error to the higher layers if it is
2909 * beyond the tolerance of the multi-bio
2910 */
1259ab75 2911 if (atomic_read(&multi->error) > multi->max_errors) {
a236aed1 2912 err = -EIO;
1259ab75
CM		 2913 } else if (err) {
2914 /*
2915 * this bio is actually up to date, we didn't
2916 * go over the max number of errors
2917 */
2918 set_bit(BIO_UPTODATE, &bio->bi_flags);
a236aed1 2919 err = 0;
1259ab75 2920 }
8790d502
CM		 2921 kfree(multi);
2922
2923 bio_endio(bio, err);
7d2b4daa 2924 } else if (!is_orig_bio) {
8790d502
CM		 2925 bio_put(bio);
2926 }
8790d502
CM		 2927}
2928
8b712842
CM		 2929struct async_sched {
2930 struct bio *bio;
2931 int rw;
2932 struct btrfs_fs_info *info;
2933 struct btrfs_work work;
2934};
2935
2936/*
2937 * see run_scheduled_bios for a description of why bios are collected for
2938 * async submit.
2939 *
2940 * This will add one bio to the pending list for a device and make sure
2941 * the work struct is scheduled.
2942 */
d397712b 2943static noinline int schedule_bio(struct btrfs_root *root,
a1b32a59
CM		 2944 struct btrfs_device *device,
2945 int rw, struct bio *bio)
8b712842
CM		 2946{
2947 int should_queue = 1;
ffbd517d 2948 struct btrfs_pending_bios *pending_bios;
8b712842
CM		 2949
2950 /* don't bother with additional async steps for reads, right now */
2951 if (!(rw & (1 << BIO_RW))) {
492bb6de 2952 bio_get(bio);
8b712842 2953 submit_bio(rw, bio);
492bb6de 2954 bio_put(bio);
8b712842
CM		 2955 return 0;
2956 }
2957
2958 /*
0986fe9e 2959 * nr_async_bios allows us to reliably return congestion to the
8b712842
CM		 2960 * higher layers. Otherwise, the async bio makes it appear we have
2961 * made progress against dirty pages when we've really just put it
2962 * on a queue for later
2963 */
0986fe9e 2964 atomic_inc(&root->fs_info->nr_async_bios);
492bb6de 2965 WARN_ON(bio->bi_next);
8b712842
CM		 2966 bio->bi_next = NULL;
2967 bio->bi_rw |= rw;
2968
2969 spin_lock(&device->io_lock);
1f98a13f 2970 if (bio_rw_flagged(bio, BIO_RW_SYNCIO))
ffbd517d
CM		 2971 pending_bios = &device->pending_sync_bios;
2972 else
2973 pending_bios = &device->pending_bios;
8b712842 2974
ffbd517d
CM		 2975 if (pending_bios->tail)
2976 pending_bios->tail->bi_next = bio;
8b712842 2977
ffbd517d
CM		 2978 pending_bios->tail = bio;
2979 if (!pending_bios->head)
2980 pending_bios->head = bio;
8b712842
CM		 2981 if (device->running_pending)
2982 should_queue = 0;
2983
2984 spin_unlock(&device->io_lock);
2985
2986 if (should_queue)
1cc127b5
CM		 2987 btrfs_queue_worker(&root->fs_info->submit_workers,
2988 &device->work);
8b712842
CM		 2989 return 0;
2990}
2991
f188591e 2992int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio,
8b712842 2993 int mirror_num, int async_submit)
0b86a832
CM		 2994{
2995 struct btrfs_mapping_tree *map_tree;
2996 struct btrfs_device *dev;
8790d502 2997 struct bio *first_bio = bio;
a62b9401 2998 u64 logical = (u64)bio->bi_sector << 9;
0b86a832
CM		 2999 u64 length = 0;
3000 u64 map_length;
cea9e445 3001 struct btrfs_multi_bio *multi = NULL;
0b86a832 3002 int ret;
8790d502
CM		 3003 int dev_nr = 0;
3004 int total_devs = 1;
0b86a832 3005
f2d8d74d 3006 length = bio->bi_size;
0b86a832
CM		 3007 map_tree = &root->fs_info->mapping_tree;
3008 map_length = length;
cea9e445 3009
f188591e
CM		 3010 ret = btrfs_map_block(map_tree, rw, logical, &map_length, &multi,
3011 mirror_num);
cea9e445
CM		 3012 BUG_ON(ret);
3013
3014 total_devs = multi->num_stripes;
3015 if (map_length < length) {
d397712b
CM		 3016 printk(KERN_CRIT "mapping failed logical %llu bio len %llu "
3017 "len %llu\n", (unsigned long long)logical,
3018 (unsigned long long)length,
3019 (unsigned long long)map_length);
cea9e445
CM		 3020 BUG();
3021 }
3022 multi->end_io = first_bio->bi_end_io;
3023 multi->private = first_bio->bi_private;
7d2b4daa 3024 multi->orig_bio = first_bio;
cea9e445
CM		 3025 atomic_set(&multi->stripes_pending, multi->num_stripes);
3026
d397712b 3027 while (dev_nr < total_devs) {
8790d502 3028 if (total_devs > 1) {
8790d502
CM		 3029 if (dev_nr < total_devs - 1) {
3030 bio = bio_clone(first_bio, GFP_NOFS);
3031 BUG_ON(!bio);
3032 } else {
3033 bio = first_bio;
3034 }
3035 bio->bi_private = multi;
3036 bio->bi_end_io = end_bio_multi_stripe;
3037 }
cea9e445
CM		 3038 bio->bi_sector = multi->stripes[dev_nr].physical >> 9;
3039 dev = multi->stripes[dev_nr].dev;
2b82032c 3040 BUG_ON(rw == WRITE && !dev->writeable);
dfe25020
CM		 3041 if (dev && dev->bdev) {
3042 bio->bi_bdev = dev->bdev;
8b712842
CM		 3043 if (async_submit)
3044 schedule_bio(root, dev, rw, bio);
3045 else
3046 submit_bio(rw, bio);
dfe25020
CM		 3047 } else {
3048 bio->bi_bdev = root->fs_info->fs_devices->latest_bdev;
3049 bio->bi_sector = logical >> 9;
dfe25020 3050 bio_endio(bio, -EIO);
dfe25020 3051 }
8790d502
CM		 3052 dev_nr++;
3053 }
cea9e445
CM		 3054 if (total_devs == 1)
3055 kfree(multi);
0b86a832
CM		 3056 return 0;
3057}
3058
a443755f 3059struct btrfs_device *btrfs_find_device(struct btrfs_root *root, u64 devid,
2b82032c 3060 u8 *uuid, u8 *fsid)
0b86a832 3061{
2b82032c
YZ		 3062 struct btrfs_device *device;
3063 struct btrfs_fs_devices *cur_devices;
3064
3065 cur_devices = root->fs_info->fs_devices;
3066 while (cur_devices) {
3067 if (!fsid ||
3068 !memcmp(cur_devices->fsid, fsid, BTRFS_UUID_SIZE)) {
3069 device = __find_device(&cur_devices->devices,
3070 devid, uuid);
3071 if (device)
3072 return device;
3073 }
3074 cur_devices = cur_devices->seed;
3075 }
3076 return NULL;
0b86a832
CM		 3077}
3078
dfe25020
CM		 3079static struct btrfs_device *add_missing_dev(struct btrfs_root *root,
3080 u64 devid, u8 *dev_uuid)
3081{
3082 struct btrfs_device *device;
3083 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
3084
3085 device = kzalloc(sizeof(*device), GFP_NOFS);
7cbd8a83 3086 if (!device)
3087 return NULL;
dfe25020
CM		 3088 list_add(&device->dev_list,
3089 &fs_devices->devices);
dfe25020
CM		 3090 device->barriers = 1;
3091 device->dev_root = root->fs_info->dev_root;
3092 device->devid = devid;
8b712842 3093 device->work.func = pending_bios_fn;
e4404d6e 3094 device->fs_devices = fs_devices;
dfe25020
CM		 3095 fs_devices->num_devices++;
3096 spin_lock_init(&device->io_lock);
d20f7043 3097 INIT_LIST_HEAD(&device->dev_alloc_list);
dfe25020
CM		 3098 memcpy(device->uuid, dev_uuid, BTRFS_UUID_SIZE);
3099 return device;
3100}
3101
0b86a832
CM		 3102static int read_one_chunk(struct btrfs_root *root, struct btrfs_key *key,
3103 struct extent_buffer *leaf,
3104 struct btrfs_chunk *chunk)
3105{
3106 struct btrfs_mapping_tree *map_tree = &root->fs_info->mapping_tree;
3107 struct map_lookup *map;
3108 struct extent_map *em;
3109 u64 logical;
3110 u64 length;
3111 u64 devid;
a443755f 3112 u8 uuid[BTRFS_UUID_SIZE];
593060d7 3113 int num_stripes;
0b86a832 3114 int ret;
593060d7 3115 int i;
0b86a832 3116
e17cade2
CM		 3117 logical = key->offset;
3118 length = btrfs_chunk_length(leaf, chunk);
a061fc8d 3119
890871be 3120 read_lock(&map_tree->map_tree.lock);
0b86a832 3121 em = lookup_extent_mapping(&map_tree->map_tree, logical, 1);
890871be 3122 read_unlock(&map_tree->map_tree.lock);
0b86a832
CM		 3123
3124 /* already mapped? */
3125 if (em && em->start <= logical && em->start + em->len > logical) {
3126 free_extent_map(em);
0b86a832
CM		 3127 return 0;
3128 } else if (em) {
3129 free_extent_map(em);
3130 }
0b86a832 3131
0b86a832
CM		 3132 em = alloc_extent_map(GFP_NOFS);
3133 if (!em)
3134 return -ENOMEM;
593060d7
CM		 3135 num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
3136 map = kmalloc(map_lookup_size(num_stripes), GFP_NOFS);
0b86a832
CM		 3137 if (!map) {
3138 free_extent_map(em);
3139 return -ENOMEM;
3140 }
3141
3142 em->bdev = (struct block_device *)map;
3143 em->start = logical;
3144 em->len = length;
3145 em->block_start = 0;
c8b97818 3146 em->block_len = em->len;
0b86a832 3147
593060d7
CM		 3148 map->num_stripes = num_stripes;
3149 map->io_width = btrfs_chunk_io_width(leaf, chunk);
3150 map->io_align = btrfs_chunk_io_align(leaf, chunk);
3151 map->sector_size = btrfs_chunk_sector_size(leaf, chunk);
3152 map->stripe_len = btrfs_chunk_stripe_len(leaf, chunk);
3153 map->type = btrfs_chunk_type(leaf, chunk);
321aecc6 3154 map->sub_stripes = btrfs_chunk_sub_stripes(leaf, chunk);
593060d7
CM		 3155 for (i = 0; i < num_stripes; i++) {
3156 map->stripes[i].physical =
3157 btrfs_stripe_offset_nr(leaf, chunk, i);
3158 devid = btrfs_stripe_devid_nr(leaf, chunk, i);
a443755f
CM		 3159 read_extent_buffer(leaf, uuid, (unsigned long)
3160 btrfs_stripe_dev_uuid_nr(chunk, i),
3161 BTRFS_UUID_SIZE);
2b82032c
YZ		 3162 map->stripes[i].dev = btrfs_find_device(root, devid, uuid,
3163 NULL);
dfe25020 3164 if (!map->stripes[i].dev && !btrfs_test_opt(root, DEGRADED)) {
593060d7
CM		 3165 kfree(map);
3166 free_extent_map(em);
3167 return -EIO;
3168 }
dfe25020
CM		 3169 if (!map->stripes[i].dev) {
3170 map->stripes[i].dev =
3171 add_missing_dev(root, devid, uuid);
3172 if (!map->stripes[i].dev) {
3173 kfree(map);
3174 free_extent_map(em);
3175 return -EIO;
3176 }
3177 }
3178 map->stripes[i].dev->in_fs_metadata = 1;
0b86a832
CM		 3179 }
3180
890871be 3181 write_lock(&map_tree->map_tree.lock);
0b86a832 3182 ret = add_extent_mapping(&map_tree->map_tree, em);
890871be 3183 write_unlock(&map_tree->map_tree.lock);
b248a415 3184 BUG_ON(ret);
0b86a832
CM		 3185 free_extent_map(em);
3186
3187 return 0;
3188}
3189
3190static int fill_device_from_item(struct extent_buffer *leaf,
3191 struct btrfs_dev_item *dev_item,
3192 struct btrfs_device *device)
3193{
3194 unsigned long ptr;
0b86a832
CM		 3195
3196 device->devid = btrfs_device_id(leaf, dev_item);
d6397bae
CB		 3197 device->disk_total_bytes = btrfs_device_total_bytes(leaf, dev_item);
3198 device->total_bytes = device->disk_total_bytes;
0b86a832
CM		 3199 device->bytes_used = btrfs_device_bytes_used(leaf, dev_item);
3200 device->type = btrfs_device_type(leaf, dev_item);
3201 device->io_align = btrfs_device_io_align(leaf, dev_item);
3202 device->io_width = btrfs_device_io_width(leaf, dev_item);
3203 device->sector_size = btrfs_device_sector_size(leaf, dev_item);
0b86a832
CM		 3204
3205 ptr = (unsigned long)btrfs_device_uuid(dev_item);
e17cade2 3206 read_extent_buffer(leaf, device->uuid, ptr, BTRFS_UUID_SIZE);
0b86a832 3207
0b86a832
CM		 3208 return 0;
3209}
3210
2b82032c
YZ		 3211static int open_seed_devices(struct btrfs_root *root, u8 *fsid)
3212{
3213 struct btrfs_fs_devices *fs_devices;
3214 int ret;
3215
3216 mutex_lock(&uuid_mutex);
3217
3218 fs_devices = root->fs_info->fs_devices->seed;
3219 while (fs_devices) {
3220 if (!memcmp(fs_devices->fsid, fsid, BTRFS_UUID_SIZE)) {
3221 ret = 0;
3222 goto out;
3223 }
3224 fs_devices = fs_devices->seed;
3225 }
3226
3227 fs_devices = find_fsid(fsid);
3228 if (!fs_devices) {
3229 ret = -ENOENT;
3230 goto out;
3231 }
e4404d6e
YZ		 3232
3233 fs_devices = clone_fs_devices(fs_devices);
3234 if (IS_ERR(fs_devices)) {
3235 ret = PTR_ERR(fs_devices);
2b82032c
YZ		 3236 goto out;
3237 }
3238
97288f2c 3239 ret = __btrfs_open_devices(fs_devices, FMODE_READ,
15916de8 3240 root->fs_info->bdev_holder);
2b82032c
YZ		 3241 if (ret)
3242 goto out;
3243
3244 if (!fs_devices->seeding) {
3245 __btrfs_close_devices(fs_devices);
e4404d6e 3246 free_fs_devices(fs_devices);
2b82032c
YZ		 3247 ret = -EINVAL;
3248 goto out;
3249 }
3250
3251 fs_devices->seed = root->fs_info->fs_devices->seed;
3252 root->fs_info->fs_devices->seed = fs_devices;
2b82032c
YZ		 3253out:
3254 mutex_unlock(&uuid_mutex);
3255 return ret;
3256}
3257
0d81ba5d 3258static int read_one_dev(struct btrfs_root *root,
0b86a832
CM		 3259 struct extent_buffer *leaf,
3260 struct btrfs_dev_item *dev_item)
3261{
3262 struct btrfs_device *device;
3263 u64 devid;
3264 int ret;
2b82032c 3265 u8 fs_uuid[BTRFS_UUID_SIZE];
a443755f
CM		 3266 u8 dev_uuid[BTRFS_UUID_SIZE];
3267
0b86a832 3268 devid = btrfs_device_id(leaf, dev_item);
a443755f
CM		 3269 read_extent_buffer(leaf, dev_uuid,
3270 (unsigned long)btrfs_device_uuid(dev_item),
3271 BTRFS_UUID_SIZE);
2b82032c
YZ		 3272 read_extent_buffer(leaf, fs_uuid,
3273 (unsigned long)btrfs_device_fsid(dev_item),
3274 BTRFS_UUID_SIZE);
3275
3276 if (memcmp(fs_uuid, root->fs_info->fsid, BTRFS_UUID_SIZE)) {
3277 ret = open_seed_devices(root, fs_uuid);
e4404d6e 3278 if (ret && !btrfs_test_opt(root, DEGRADED))
2b82032c 3279 return ret;
2b82032c
YZ		 3280 }
3281
3282 device = btrfs_find_device(root, devid, dev_uuid, fs_uuid);
3283 if (!device || !device->bdev) {
e4404d6e 3284 if (!btrfs_test_opt(root, DEGRADED))
2b82032c
YZ		 3285 return -EIO;
3286
3287 if (!device) {
d397712b
CM		 3288 printk(KERN_WARNING "warning devid %llu missing\n",
3289 (unsigned long long)devid);
2b82032c
YZ		 3290 device = add_missing_dev(root, devid, dev_uuid);
3291 if (!device)
3292 return -ENOMEM;
3293 }
3294 }
3295
3296 if (device->fs_devices != root->fs_info->fs_devices) {
3297 BUG_ON(device->writeable);
3298 if (device->generation !=
3299 btrfs_device_generation(leaf, dev_item))
3300 return -EINVAL;
6324fbf3 3301 }
0b86a832
CM		 3302
3303 fill_device_from_item(leaf, dev_item, device);
3304 device->dev_root = root->fs_info->dev_root;
dfe25020 3305 device->in_fs_metadata = 1;
2b82032c
YZ		 3306 if (device->writeable)
3307 device->fs_devices->total_rw_bytes += device->total_bytes;
0b86a832 3308 ret = 0;
0b86a832
CM		 3309 return ret;
3310}
3311
0d81ba5d
CM		 3312int btrfs_read_super_device(struct btrfs_root *root, struct extent_buffer *buf)
3313{
3314 struct btrfs_dev_item *dev_item;
3315
3316 dev_item = (struct btrfs_dev_item *)offsetof(struct btrfs_super_block,
3317 dev_item);
3318 return read_one_dev(root, buf, dev_item);
3319}
3320
e4404d6e 3321int btrfs_read_sys_array(struct btrfs_root *root)
0b86a832
CM		 3322{
3323 struct btrfs_super_block *super_copy = &root->fs_info->super_copy;
a061fc8d 3324 struct extent_buffer *sb;
0b86a832 3325 struct btrfs_disk_key *disk_key;
0b86a832 3326 struct btrfs_chunk *chunk;
84eed90f
CM		 3327 u8 *ptr;
3328 unsigned long sb_ptr;
3329 int ret = 0;
0b86a832
CM		 3330 u32 num_stripes;
3331 u32 array_size;
3332 u32 len = 0;
0b86a832 3333 u32 cur;
84eed90f 3334 struct btrfs_key key;
0b86a832 3335
e4404d6e 3336 sb = btrfs_find_create_tree_block(root, BTRFS_SUPER_INFO_OFFSET,
a061fc8d
CM		 3337 BTRFS_SUPER_INFO_SIZE);
3338 if (!sb)
3339 return -ENOMEM;
3340 btrfs_set_buffer_uptodate(sb);
4008c04a
CM		 3341 btrfs_set_buffer_lockdep_class(sb, 0);
3342
a061fc8d 3343 write_extent_buffer(sb, super_copy, 0, BTRFS_SUPER_INFO_SIZE);
0b86a832
CM		 3344 array_size = btrfs_super_sys_array_size(super_copy);
3345
0b86a832
CM		 3346 ptr = super_copy->sys_chunk_array;
3347 sb_ptr = offsetof(struct btrfs_super_block, sys_chunk_array);
3348 cur = 0;
3349
3350 while (cur < array_size) {
3351 disk_key = (struct btrfs_disk_key *)ptr;
3352 btrfs_disk_key_to_cpu(&key, disk_key);
3353
a061fc8d 3354 len = sizeof(*disk_key); ptr += len;
0b86a832
CM		 3355 sb_ptr += len;
3356 cur += len;
3357
0d81ba5d 3358 if (key.type == BTRFS_CHUNK_ITEM_KEY) {
0b86a832 3359 chunk = (struct btrfs_chunk *)sb_ptr;
0d81ba5d 3360 ret = read_one_chunk(root, &key, sb, chunk);
84eed90f
CM		 3361 if (ret)
3362 break;
0b86a832
CM		 3363 num_stripes = btrfs_chunk_num_stripes(sb, chunk);
3364 len = btrfs_chunk_item_size(num_stripes);
3365 } else {
84eed90f
CM		 3366 ret = -EIO;
3367 break;
0b86a832
CM		 3368 }
3369 ptr += len;
3370 sb_ptr += len;
3371 cur += len;
3372 }
a061fc8d 3373 free_extent_buffer(sb);
84eed90f 3374 return ret;
0b86a832
CM		 3375}
3376
3377int btrfs_read_chunk_tree(struct btrfs_root *root)
3378{
3379 struct btrfs_path *path;
3380 struct extent_buffer *leaf;
3381 struct btrfs_key key;
3382 struct btrfs_key found_key;
3383 int ret;
3384 int slot;
3385
3386 root = root->fs_info->chunk_root;
3387
3388 path = btrfs_alloc_path();
3389 if (!path)
3390 return -ENOMEM;
3391
3392 /* first we search for all of the device items, and then we
3393 * read in all of the chunk items. This way we can create chunk
3394 * mappings that reference all of the devices that are afound
3395 */
3396 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
3397 key.offset = 0;
3398 key.type = 0;
3399again:
3400 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
ab59381e
ZL		 3401 if (ret < 0)
3402 goto error;
d397712b 3403 while (1) {
0b86a832
CM		 3404 leaf = path->nodes[0];
3405 slot = path->slots[0];
3406 if (slot >= btrfs_header_nritems(leaf)) {
3407 ret = btrfs_next_leaf(root, path);
3408 if (ret == 0)
3409 continue;
3410 if (ret < 0)
3411 goto error;
3412 break;
3413 }
3414 btrfs_item_key_to_cpu(leaf, &found_key, slot);
3415 if (key.objectid == BTRFS_DEV_ITEMS_OBJECTID) {
3416 if (found_key.objectid != BTRFS_DEV_ITEMS_OBJECTID)
3417 break;
3418 if (found_key.type == BTRFS_DEV_ITEM_KEY) {
3419 struct btrfs_dev_item *dev_item;
3420 dev_item = btrfs_item_ptr(leaf, slot,
3421 struct btrfs_dev_item);
0d81ba5d 3422 ret = read_one_dev(root, leaf, dev_item);
2b82032c
YZ		 3423 if (ret)
3424 goto error;
0b86a832
CM		 3425 }
3426 } else if (found_key.type == BTRFS_CHUNK_ITEM_KEY) {
3427 struct btrfs_chunk *chunk;
3428 chunk = btrfs_item_ptr(leaf, slot, struct btrfs_chunk);
3429 ret = read_one_chunk(root, &found_key, leaf, chunk);
2b82032c
YZ		 3430 if (ret)
3431 goto error;
0b86a832
CM		 3432 }
3433 path->slots[0]++;
3434 }
3435 if (key.objectid == BTRFS_DEV_ITEMS_OBJECTID) {
3436 key.objectid = 0;
3437 btrfs_release_path(root, path);
3438 goto again;
3439 }
0b86a832
CM		 3440 ret = 0;
3441error:
2b82032c 3442 btrfs_free_path(path);
0b86a832
CM		 3443 return ret;
3444}
Linux 6.x block layer and io_uring tree(s)