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include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit...
[net-next-2.6.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)) {
2b82032c 2202 num_stripes = min_t(u64, 2, fs_devices->rw_devices);
9b3f68b9
CM		 2203 if (num_stripes < 2)
2204 return -ENOSPC;
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 }
2248 /* we don't want tiny stripes */
a40a90a0 2249 calc_size = max_t(u64, min_stripe_size, calc_size);
9b3f68b9 2250
9b3f68b9
CM		 2251 do_div(calc_size, stripe_len);
2252 calc_size *= stripe_len;
2253
2b82032c 2254 cur = fs_devices->alloc_list.next;
6324fbf3 2255 index = 0;
611f0e00
CM		 2256
2257 if (type & BTRFS_BLOCK_GROUP_DUP)
2258 min_free = calc_size * 2;
9b3f68b9
CM		 2259 else
2260 min_free = calc_size;
611f0e00 2261
0f9dd46c
JB		 2262 /*
2263 * we add 1MB because we never use the first 1MB of the device, unless
2264 * we've looped, then we are likely allocating the maximum amount of
2265 * space left already
2266 */
2267 if (!looped)
2268 min_free += 1024 * 1024;
ad5bd91e 2269
2b82032c 2270 INIT_LIST_HEAD(&private_devs);
d397712b 2271 while (index < num_stripes) {
b3075717 2272 device = list_entry(cur, struct btrfs_device, dev_alloc_list);
2b82032c 2273 BUG_ON(!device->writeable);
dfe25020
CM		 2274 if (device->total_bytes > device->bytes_used)
2275 avail = device->total_bytes - device->bytes_used;
2276 else
2277 avail = 0;
6324fbf3 2278 cur = cur->next;
8f18cf13 2279
dfe25020 2280 if (device->in_fs_metadata && avail >= min_free) {
2b82032c 2281 ret = find_free_dev_extent(trans, device,
9779b72f
CM		 2282 min_free, &dev_offset,
2283 &max_avail);
8f18cf13
CM		 2284 if (ret == 0) {
2285 list_move_tail(&device->dev_alloc_list,
2286 &private_devs);
2b82032c
YZ		 2287 map->stripes[index].dev = device;
2288 map->stripes[index].physical = dev_offset;
611f0e00 2289 index++;
2b82032c
YZ		 2290 if (type & BTRFS_BLOCK_GROUP_DUP) {
2291 map->stripes[index].dev = device;
2292 map->stripes[index].physical =
2293 dev_offset + calc_size;
8f18cf13 2294 index++;
2b82032c 2295 }
8f18cf13 2296 }
dfe25020 2297 } else if (device->in_fs_metadata && avail > max_avail)
a40a90a0 2298 max_avail = avail;
2b82032c 2299 if (cur == &fs_devices->alloc_list)
6324fbf3
CM		 2300 break;
2301 }
2b82032c 2302 list_splice(&private_devs, &fs_devices->alloc_list);
6324fbf3 2303 if (index < num_stripes) {
a40a90a0
CM		 2304 if (index >= min_stripes) {
2305 num_stripes = index;
2306 if (type & (BTRFS_BLOCK_GROUP_RAID10)) {
2307 num_stripes /= sub_stripes;
2308 num_stripes *= sub_stripes;
2309 }
2310 looped = 1;
2311 goto again;
2312 }
6324fbf3
CM		 2313 if (!looped && max_avail > 0) {
2314 looped = 1;
2315 calc_size = max_avail;
2316 goto again;
2317 }
2b82032c 2318 kfree(map);
6324fbf3
CM		 2319 return -ENOSPC;
2320 }
2b82032c
YZ		 2321 map->sector_size = extent_root->sectorsize;
2322 map->stripe_len = stripe_len;
2323 map->io_align = stripe_len;
2324 map->io_width = stripe_len;
2325 map->type = type;
2326 map->num_stripes = num_stripes;
2327 map->sub_stripes = sub_stripes;
0b86a832 2328
2b82032c
YZ		 2329 *map_ret = map;
2330 *stripe_size = calc_size;
2331 *num_bytes = chunk_bytes_by_type(type, calc_size,
2332 num_stripes, sub_stripes);
0b86a832 2333
2b82032c
YZ		 2334 em = alloc_extent_map(GFP_NOFS);
2335 if (!em) {
2336 kfree(map);
593060d7
CM		 2337 return -ENOMEM;
2338 }
2b82032c
YZ		 2339 em->bdev = (struct block_device *)map;
2340 em->start = start;
2341 em->len = *num_bytes;
2342 em->block_start = 0;
2343 em->block_len = em->len;
593060d7 2344
2b82032c 2345 em_tree = &extent_root->fs_info->mapping_tree.map_tree;
890871be 2346 write_lock(&em_tree->lock);
2b82032c 2347 ret = add_extent_mapping(em_tree, em);
890871be 2348 write_unlock(&em_tree->lock);
2b82032c
YZ		 2349 BUG_ON(ret);
2350 free_extent_map(em);
0b86a832 2351
2b82032c
YZ		 2352 ret = btrfs_make_block_group(trans, extent_root, 0, type,
2353 BTRFS_FIRST_CHUNK_TREE_OBJECTID,
2354 start, *num_bytes);
2355 BUG_ON(ret);
611f0e00 2356
2b82032c
YZ		 2357 index = 0;
2358 while (index < map->num_stripes) {
2359 device = map->stripes[index].dev;
2360 dev_offset = map->stripes[index].physical;
0b86a832
CM		 2361
2362 ret = btrfs_alloc_dev_extent(trans, device,
2b82032c
YZ		 2363 info->chunk_root->root_key.objectid,
2364 BTRFS_FIRST_CHUNK_TREE_OBJECTID,
2365 start, dev_offset, calc_size);
0b86a832 2366 BUG_ON(ret);
2b82032c
YZ		 2367 index++;
2368 }
2369
2370 return 0;
2371}
2372
2373static int __finish_chunk_alloc(struct btrfs_trans_handle *trans,
2374 struct btrfs_root *extent_root,
2375 struct map_lookup *map, u64 chunk_offset,
2376 u64 chunk_size, u64 stripe_size)
2377{
2378 u64 dev_offset;
2379 struct btrfs_key key;
2380 struct btrfs_root *chunk_root = extent_root->fs_info->chunk_root;
2381 struct btrfs_device *device;
2382 struct btrfs_chunk *chunk;
2383 struct btrfs_stripe *stripe;
2384 size_t item_size = btrfs_chunk_item_size(map->num_stripes);
2385 int index = 0;
2386 int ret;
2387
2388 chunk = kzalloc(item_size, GFP_NOFS);
2389 if (!chunk)
2390 return -ENOMEM;
2391
2392 index = 0;
2393 while (index < map->num_stripes) {
2394 device = map->stripes[index].dev;
2395 device->bytes_used += stripe_size;
0b86a832
CM		 2396 ret = btrfs_update_device(trans, device);
2397 BUG_ON(ret);
2b82032c
YZ		 2398 index++;
2399 }
2400
2401 index = 0;
2402 stripe = &chunk->stripe;
2403 while (index < map->num_stripes) {
2404 device = map->stripes[index].dev;
2405 dev_offset = map->stripes[index].physical;
0b86a832 2406
e17cade2
CM		 2407 btrfs_set_stack_stripe_devid(stripe, device->devid);
2408 btrfs_set_stack_stripe_offset(stripe, dev_offset);
2409 memcpy(stripe->dev_uuid, device->uuid, BTRFS_UUID_SIZE);
2b82032c 2410 stripe++;
0b86a832
CM		 2411 index++;
2412 }
2413
2b82032c 2414 btrfs_set_stack_chunk_length(chunk, chunk_size);
0b86a832 2415 btrfs_set_stack_chunk_owner(chunk, extent_root->root_key.objectid);
2b82032c
YZ		 2416 btrfs_set_stack_chunk_stripe_len(chunk, map->stripe_len);
2417 btrfs_set_stack_chunk_type(chunk, map->type);
2418 btrfs_set_stack_chunk_num_stripes(chunk, map->num_stripes);
2419 btrfs_set_stack_chunk_io_align(chunk, map->stripe_len);
2420 btrfs_set_stack_chunk_io_width(chunk, map->stripe_len);
0b86a832 2421 btrfs_set_stack_chunk_sector_size(chunk, extent_root->sectorsize);
2b82032c 2422 btrfs_set_stack_chunk_sub_stripes(chunk, map->sub_stripes);
0b86a832 2423
2b82032c
YZ		 2424 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
2425 key.type = BTRFS_CHUNK_ITEM_KEY;
2426 key.offset = chunk_offset;
0b86a832 2427
2b82032c
YZ		 2428 ret = btrfs_insert_item(trans, chunk_root, &key, chunk, item_size);
2429 BUG_ON(ret);
0b86a832 2430
2b82032c
YZ		 2431 if (map->type & BTRFS_BLOCK_GROUP_SYSTEM) {
2432 ret = btrfs_add_system_chunk(trans, chunk_root, &key, chunk,
2433 item_size);
8f18cf13
CM		 2434 BUG_ON(ret);
2435 }
0b86a832 2436 kfree(chunk);
2b82032c
YZ		 2437 return 0;
2438}
0b86a832 2439
2b82032c
YZ		 2440/*
2441 * Chunk allocation falls into two parts. The first part does works
2442 * that make the new allocated chunk useable, but not do any operation
2443 * that modifies the chunk tree. The second part does the works that
2444 * require modifying the chunk tree. This division is important for the
2445 * bootstrap process of adding storage to a seed btrfs.
2446 */
2447int btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
2448 struct btrfs_root *extent_root, u64 type)
2449{
2450 u64 chunk_offset;
2451 u64 chunk_size;
2452 u64 stripe_size;
2453 struct map_lookup *map;
2454 struct btrfs_root *chunk_root = extent_root->fs_info->chunk_root;
2455 int ret;
2456
2457 ret = find_next_chunk(chunk_root, BTRFS_FIRST_CHUNK_TREE_OBJECTID,
2458 &chunk_offset);
2459 if (ret)
2460 return ret;
2461
2462 ret = __btrfs_alloc_chunk(trans, extent_root, &map, &chunk_size,
2463 &stripe_size, chunk_offset, type);
2464 if (ret)
2465 return ret;
2466
2467 ret = __finish_chunk_alloc(trans, extent_root, map, chunk_offset,
2468 chunk_size, stripe_size);
2469 BUG_ON(ret);
2470 return 0;
2471}
2472
d397712b 2473static noinline int init_first_rw_device(struct btrfs_trans_handle *trans,
2b82032c
YZ		 2474 struct btrfs_root *root,
2475 struct btrfs_device *device)
2476{
2477 u64 chunk_offset;
2478 u64 sys_chunk_offset;
2479 u64 chunk_size;
2480 u64 sys_chunk_size;
2481 u64 stripe_size;
2482 u64 sys_stripe_size;
2483 u64 alloc_profile;
2484 struct map_lookup *map;
2485 struct map_lookup *sys_map;
2486 struct btrfs_fs_info *fs_info = root->fs_info;
2487 struct btrfs_root *extent_root = fs_info->extent_root;
2488 int ret;
2489
2490 ret = find_next_chunk(fs_info->chunk_root,
2491 BTRFS_FIRST_CHUNK_TREE_OBJECTID, &chunk_offset);
2492 BUG_ON(ret);
2493
2494 alloc_profile = BTRFS_BLOCK_GROUP_METADATA |
2495 (fs_info->metadata_alloc_profile &
2496 fs_info->avail_metadata_alloc_bits);
2497 alloc_profile = btrfs_reduce_alloc_profile(root, alloc_profile);
2498
2499 ret = __btrfs_alloc_chunk(trans, extent_root, &map, &chunk_size,
2500 &stripe_size, chunk_offset, alloc_profile);
2501 BUG_ON(ret);
2502
2503 sys_chunk_offset = chunk_offset + chunk_size;
2504
2505 alloc_profile = BTRFS_BLOCK_GROUP_SYSTEM |
2506 (fs_info->system_alloc_profile &
2507 fs_info->avail_system_alloc_bits);
2508 alloc_profile = btrfs_reduce_alloc_profile(root, alloc_profile);
2509
2510 ret = __btrfs_alloc_chunk(trans, extent_root, &sys_map,
2511 &sys_chunk_size, &sys_stripe_size,
2512 sys_chunk_offset, alloc_profile);
2513 BUG_ON(ret);
2514
2515 ret = btrfs_add_device(trans, fs_info->chunk_root, device);
2516 BUG_ON(ret);
2517
2518 /*
2519 * Modifying chunk tree needs allocating new blocks from both
2520 * system block group and metadata block group. So we only can
2521 * do operations require modifying the chunk tree after both
2522 * block groups were created.
2523 */
2524 ret = __finish_chunk_alloc(trans, extent_root, map, chunk_offset,
2525 chunk_size, stripe_size);
2526 BUG_ON(ret);
2527
2528 ret = __finish_chunk_alloc(trans, extent_root, sys_map,
2529 sys_chunk_offset, sys_chunk_size,
2530 sys_stripe_size);
b248a415 2531 BUG_ON(ret);
2b82032c
YZ		 2532 return 0;
2533}
2534
2535int btrfs_chunk_readonly(struct btrfs_root *root, u64 chunk_offset)
2536{
2537 struct extent_map *em;
2538 struct map_lookup *map;
2539 struct btrfs_mapping_tree *map_tree = &root->fs_info->mapping_tree;
2540 int readonly = 0;
2541 int i;
2542
890871be 2543 read_lock(&map_tree->map_tree.lock);
2b82032c 2544 em = lookup_extent_mapping(&map_tree->map_tree, chunk_offset, 1);
890871be 2545 read_unlock(&map_tree->map_tree.lock);
2b82032c
YZ		 2546 if (!em)
2547 return 1;
2548
f48b9075
JB		 2549 if (btrfs_test_opt(root, DEGRADED)) {
2550 free_extent_map(em);
2551 return 0;
2552 }
2553
2b82032c
YZ		 2554 map = (struct map_lookup *)em->bdev;
2555 for (i = 0; i < map->num_stripes; i++) {
2556 if (!map->stripes[i].dev->writeable) {
2557 readonly = 1;
2558 break;
2559 }
2560 }
0b86a832 2561 free_extent_map(em);
2b82032c 2562 return readonly;
0b86a832
CM		 2563}
2564
2565void btrfs_mapping_init(struct btrfs_mapping_tree *tree)
2566{
2567 extent_map_tree_init(&tree->map_tree, GFP_NOFS);
2568}
2569
2570void btrfs_mapping_tree_free(struct btrfs_mapping_tree *tree)
2571{
2572 struct extent_map *em;
2573
d397712b 2574 while (1) {
890871be 2575 write_lock(&tree->map_tree.lock);
0b86a832
CM		 2576 em = lookup_extent_mapping(&tree->map_tree, 0, (u64)-1);
2577 if (em)
2578 remove_extent_mapping(&tree->map_tree, em);
890871be 2579 write_unlock(&tree->map_tree.lock);
0b86a832
CM		 2580 if (!em)
2581 break;
2582 kfree(em->bdev);
2583 /* once for us */
2584 free_extent_map(em);
2585 /* once for the tree */
2586 free_extent_map(em);
2587 }
2588}
2589
f188591e
CM		 2590int btrfs_num_copies(struct btrfs_mapping_tree *map_tree, u64 logical, u64 len)
2591{
2592 struct extent_map *em;
2593 struct map_lookup *map;
2594 struct extent_map_tree *em_tree = &map_tree->map_tree;
2595 int ret;
2596
890871be 2597 read_lock(&em_tree->lock);
f188591e 2598 em = lookup_extent_mapping(em_tree, logical, len);
890871be 2599 read_unlock(&em_tree->lock);
f188591e
CM		 2600 BUG_ON(!em);
2601
2602 BUG_ON(em->start > logical || em->start + em->len < logical);
2603 map = (struct map_lookup *)em->bdev;
2604 if (map->type & (BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID1))
2605 ret = map->num_stripes;
321aecc6
CM		 2606 else if (map->type & BTRFS_BLOCK_GROUP_RAID10)
2607 ret = map->sub_stripes;
f188591e
CM		 2608 else
2609 ret = 1;
2610 free_extent_map(em);
f188591e
CM		 2611 return ret;
2612}
2613
dfe25020
CM		 2614static int find_live_mirror(struct map_lookup *map, int first, int num,
2615 int optimal)
2616{
2617 int i;
2618 if (map->stripes[optimal].dev->bdev)
2619 return optimal;
2620 for (i = first; i < first + num; i++) {
2621 if (map->stripes[i].dev->bdev)
2622 return i;
2623 }
2624 /* we couldn't find one that doesn't fail. Just return something
2625 * and the io error handling code will clean up eventually
2626 */
2627 return optimal;
2628}
2629
f2d8d74d
CM		 2630static int __btrfs_map_block(struct btrfs_mapping_tree *map_tree, int rw,
2631 u64 logical, u64 *length,
2632 struct btrfs_multi_bio **multi_ret,
2633 int mirror_num, struct page *unplug_page)
0b86a832
CM		 2634{
2635 struct extent_map *em;
2636 struct map_lookup *map;
2637 struct extent_map_tree *em_tree = &map_tree->map_tree;
2638 u64 offset;
593060d7
CM		 2639 u64 stripe_offset;
2640 u64 stripe_nr;
cea9e445 2641 int stripes_allocated = 8;
321aecc6 2642 int stripes_required = 1;
593060d7 2643 int stripe_index;
cea9e445 2644 int i;
f2d8d74d 2645 int num_stripes;
a236aed1 2646 int max_errors = 0;
cea9e445 2647 struct btrfs_multi_bio *multi = NULL;
0b86a832 2648
d397712b 2649 if (multi_ret && !(rw & (1 << BIO_RW)))
cea9e445 2650 stripes_allocated = 1;
cea9e445
CM		 2651again:
2652 if (multi_ret) {
2653 multi = kzalloc(btrfs_multi_bio_size(stripes_allocated),
2654 GFP_NOFS);
2655 if (!multi)
2656 return -ENOMEM;
a236aed1
CM		 2657
2658 atomic_set(&multi->error, 0);
cea9e445 2659 }
0b86a832 2660
890871be 2661 read_lock(&em_tree->lock);
0b86a832 2662 em = lookup_extent_mapping(em_tree, logical, *length);
890871be 2663 read_unlock(&em_tree->lock);
f2d8d74d 2664
2423fdfb
JS		 2665 if (!em && unplug_page) {
2666 kfree(multi);
f2d8d74d 2667 return 0;
2423fdfb 2668 }
f2d8d74d 2669
3b951516 2670 if (!em) {
d397712b
CM		 2671 printk(KERN_CRIT "unable to find logical %llu len %llu\n",
2672 (unsigned long long)logical,
2673 (unsigned long long)*length);
f2d8d74d 2674 BUG();
3b951516 2675 }
0b86a832
CM		 2676
2677 BUG_ON(em->start > logical || em->start + em->len < logical);
2678 map = (struct map_lookup *)em->bdev;
2679 offset = logical - em->start;
593060d7 2680
f188591e
CM		 2681 if (mirror_num > map->num_stripes)
2682 mirror_num = 0;
2683
cea9e445 2684 /* if our multi bio struct is too small, back off and try again */
321aecc6
CM		 2685 if (rw & (1 << BIO_RW)) {
2686 if (map->type & (BTRFS_BLOCK_GROUP_RAID1 |
2687 BTRFS_BLOCK_GROUP_DUP)) {
2688 stripes_required = map->num_stripes;
a236aed1 2689 max_errors = 1;
321aecc6
CM		 2690 } else if (map->type & BTRFS_BLOCK_GROUP_RAID10) {
2691 stripes_required = map->sub_stripes;
a236aed1 2692 max_errors = 1;
321aecc6
CM		 2693 }
2694 }
ffbd517d 2695 if (multi_ret && (rw & (1 << BIO_RW)) &&
321aecc6 2696 stripes_allocated < stripes_required) {
cea9e445 2697 stripes_allocated = map->num_stripes;
cea9e445
CM		 2698 free_extent_map(em);
2699 kfree(multi);
2700 goto again;
2701 }
593060d7
CM		 2702 stripe_nr = offset;
2703 /*
2704 * stripe_nr counts the total number of stripes we have to stride
2705 * to get to this block
2706 */
2707 do_div(stripe_nr, map->stripe_len);
2708
2709 stripe_offset = stripe_nr * map->stripe_len;
2710 BUG_ON(offset < stripe_offset);
2711
2712 /* stripe_offset is the offset of this block in its stripe*/
2713 stripe_offset = offset - stripe_offset;
2714
cea9e445 2715 if (map->type & (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID1 |
321aecc6 2716 BTRFS_BLOCK_GROUP_RAID10 |
cea9e445
CM		 2717 BTRFS_BLOCK_GROUP_DUP)) {
2718 /* we limit the length of each bio to what fits in a stripe */
2719 *length = min_t(u64, em->len - offset,
2720 map->stripe_len - stripe_offset);
2721 } else {
2722 *length = em->len - offset;
2723 }
f2d8d74d
CM		 2724
2725 if (!multi_ret && !unplug_page)
cea9e445
CM		 2726 goto out;
2727
f2d8d74d 2728 num_stripes = 1;
cea9e445 2729 stripe_index = 0;
8790d502 2730 if (map->type & BTRFS_BLOCK_GROUP_RAID1) {
f2d8d74d
CM		 2731 if (unplug_page || (rw & (1 << BIO_RW)))
2732 num_stripes = map->num_stripes;
2fff734f 2733 else if (mirror_num)
f188591e 2734 stripe_index = mirror_num - 1;
dfe25020
CM		 2735 else {
2736 stripe_index = find_live_mirror(map, 0,
2737 map->num_stripes,
2738 current->pid % map->num_stripes);
2739 }
2fff734f 2740
611f0e00 2741 } else if (map->type & BTRFS_BLOCK_GROUP_DUP) {
cea9e445 2742 if (rw & (1 << BIO_RW))
f2d8d74d 2743 num_stripes = map->num_stripes;
f188591e
CM		 2744 else if (mirror_num)
2745 stripe_index = mirror_num - 1;
2fff734f 2746
321aecc6
CM		 2747 } else if (map->type & BTRFS_BLOCK_GROUP_RAID10) {
2748 int factor = map->num_stripes / map->sub_stripes;
321aecc6
CM		 2749
2750 stripe_index = do_div(stripe_nr, factor);
2751 stripe_index *= map->sub_stripes;
2752
f2d8d74d
CM		 2753 if (unplug_page || (rw & (1 << BIO_RW)))
2754 num_stripes = map->sub_stripes;
321aecc6
CM		 2755 else if (mirror_num)
2756 stripe_index += mirror_num - 1;
dfe25020
CM		 2757 else {
2758 stripe_index = find_live_mirror(map, stripe_index,
2759 map->sub_stripes, stripe_index +
2760 current->pid % map->sub_stripes);
2761 }
8790d502
CM		 2762 } else {
2763 /*
2764 * after this do_div call, stripe_nr is the number of stripes
2765 * on this device we have to walk to find the data, and
2766 * stripe_index is the number of our device in the stripe array
2767 */
2768 stripe_index = do_div(stripe_nr, map->num_stripes);
2769 }
593060d7 2770 BUG_ON(stripe_index >= map->num_stripes);
cea9e445 2771
f2d8d74d
CM		 2772 for (i = 0; i < num_stripes; i++) {
2773 if (unplug_page) {
2774 struct btrfs_device *device;
2775 struct backing_dev_info *bdi;
2776
2777 device = map->stripes[stripe_index].dev;
dfe25020
CM		 2778 if (device->bdev) {
2779 bdi = blk_get_backing_dev_info(device->bdev);
d397712b 2780 if (bdi->unplug_io_fn)
dfe25020 2781 bdi->unplug_io_fn(bdi, unplug_page);
f2d8d74d
CM		 2782 }
2783 } else {
2784 multi->stripes[i].physical =
2785 map->stripes[stripe_index].physical +
2786 stripe_offset + stripe_nr * map->stripe_len;
2787 multi->stripes[i].dev = map->stripes[stripe_index].dev;
2788 }
cea9e445 2789 stripe_index++;
593060d7 2790 }
f2d8d74d
CM		 2791 if (multi_ret) {
2792 *multi_ret = multi;
2793 multi->num_stripes = num_stripes;
a236aed1 2794 multi->max_errors = max_errors;
f2d8d74d 2795 }
cea9e445 2796out:
0b86a832 2797 free_extent_map(em);
0b86a832
CM		 2798 return 0;
2799}
2800
f2d8d74d
CM		 2801int btrfs_map_block(struct btrfs_mapping_tree *map_tree, int rw,
2802 u64 logical, u64 *length,
2803 struct btrfs_multi_bio **multi_ret, int mirror_num)
2804{
2805 return __btrfs_map_block(map_tree, rw, logical, length, multi_ret,
2806 mirror_num, NULL);
2807}
2808
a512bbf8
YZ		 2809int btrfs_rmap_block(struct btrfs_mapping_tree *map_tree,
2810 u64 chunk_start, u64 physical, u64 devid,
2811 u64 **logical, int *naddrs, int *stripe_len)
2812{
2813 struct extent_map_tree *em_tree = &map_tree->map_tree;
2814 struct extent_map *em;
2815 struct map_lookup *map;
2816 u64 *buf;
2817 u64 bytenr;
2818 u64 length;
2819 u64 stripe_nr;
2820 int i, j, nr = 0;
2821
890871be 2822 read_lock(&em_tree->lock);
a512bbf8 2823 em = lookup_extent_mapping(em_tree, chunk_start, 1);
890871be 2824 read_unlock(&em_tree->lock);
a512bbf8
YZ		 2825
2826 BUG_ON(!em || em->start != chunk_start);
2827 map = (struct map_lookup *)em->bdev;
2828
2829 length = em->len;
2830 if (map->type & BTRFS_BLOCK_GROUP_RAID10)
2831 do_div(length, map->num_stripes / map->sub_stripes);
2832 else if (map->type & BTRFS_BLOCK_GROUP_RAID0)
2833 do_div(length, map->num_stripes);
2834
2835 buf = kzalloc(sizeof(u64) * map->num_stripes, GFP_NOFS);
2836 BUG_ON(!buf);
2837
2838 for (i = 0; i < map->num_stripes; i++) {
2839 if (devid && map->stripes[i].dev->devid != devid)
2840 continue;
2841 if (map->stripes[i].physical > physical ||
2842 map->stripes[i].physical + length <= physical)
2843 continue;
2844
2845 stripe_nr = physical - map->stripes[i].physical;
2846 do_div(stripe_nr, map->stripe_len);
2847
2848 if (map->type & BTRFS_BLOCK_GROUP_RAID10) {
2849 stripe_nr = stripe_nr * map->num_stripes + i;
2850 do_div(stripe_nr, map->sub_stripes);
2851 } else if (map->type & BTRFS_BLOCK_GROUP_RAID0) {
2852 stripe_nr = stripe_nr * map->num_stripes + i;
2853 }
2854 bytenr = chunk_start + stripe_nr * map->stripe_len;
934d375b 2855 WARN_ON(nr >= map->num_stripes);
a512bbf8
YZ		 2856 for (j = 0; j < nr; j++) {
2857 if (buf[j] == bytenr)
2858 break;
2859 }
934d375b
CM		 2860 if (j == nr) {
2861 WARN_ON(nr >= map->num_stripes);
a512bbf8 2862 buf[nr++] = bytenr;
934d375b 2863 }
a512bbf8
YZ		 2864 }
2865
a512bbf8
YZ		 2866 *logical = buf;
2867 *naddrs = nr;
2868 *stripe_len = map->stripe_len;
2869
2870 free_extent_map(em);
2871 return 0;
2872}
2873
f2d8d74d
CM		 2874int btrfs_unplug_page(struct btrfs_mapping_tree *map_tree,
2875 u64 logical, struct page *page)
2876{
2877 u64 length = PAGE_CACHE_SIZE;
2878 return __btrfs_map_block(map_tree, READ, logical, &length,
2879 NULL, 0, page);
2880}
2881
8790d502 2882static void end_bio_multi_stripe(struct bio *bio, int err)
8790d502 2883{
cea9e445 2884 struct btrfs_multi_bio *multi = bio->bi_private;
7d2b4daa 2885 int is_orig_bio = 0;
8790d502 2886
8790d502 2887 if (err)
a236aed1 2888 atomic_inc(&multi->error);
8790d502 2889
7d2b4daa
CM		 2890 if (bio == multi->orig_bio)
2891 is_orig_bio = 1;
2892
cea9e445 2893 if (atomic_dec_and_test(&multi->stripes_pending)) {
7d2b4daa
CM		 2894 if (!is_orig_bio) {
2895 bio_put(bio);
2896 bio = multi->orig_bio;
2897 }
8790d502
CM		 2898 bio->bi_private = multi->private;
2899 bio->bi_end_io = multi->end_io;
a236aed1
CM		 2900 /* only send an error to the higher layers if it is
2901 * beyond the tolerance of the multi-bio
2902 */
1259ab75 2903 if (atomic_read(&multi->error) > multi->max_errors) {
a236aed1 2904 err = -EIO;
1259ab75
CM		 2905 } else if (err) {
2906 /*
2907 * this bio is actually up to date, we didn't
2908 * go over the max number of errors
2909 */
2910 set_bit(BIO_UPTODATE, &bio->bi_flags);
a236aed1 2911 err = 0;
1259ab75 2912 }
8790d502
CM		 2913 kfree(multi);
2914
2915 bio_endio(bio, err);
7d2b4daa 2916 } else if (!is_orig_bio) {
8790d502
CM		 2917 bio_put(bio);
2918 }
8790d502
CM		 2919}
2920
8b712842
CM		 2921struct async_sched {
2922 struct bio *bio;
2923 int rw;
2924 struct btrfs_fs_info *info;
2925 struct btrfs_work work;
2926};
2927
2928/*
2929 * see run_scheduled_bios for a description of why bios are collected for
2930 * async submit.
2931 *
2932 * This will add one bio to the pending list for a device and make sure
2933 * the work struct is scheduled.
2934 */
d397712b 2935static noinline int schedule_bio(struct btrfs_root *root,
a1b32a59
CM		 2936 struct btrfs_device *device,
2937 int rw, struct bio *bio)
8b712842
CM		 2938{
2939 int should_queue = 1;
ffbd517d 2940 struct btrfs_pending_bios *pending_bios;
8b712842
CM		 2941
2942 /* don't bother with additional async steps for reads, right now */
2943 if (!(rw & (1 << BIO_RW))) {
492bb6de 2944 bio_get(bio);
8b712842 2945 submit_bio(rw, bio);
492bb6de 2946 bio_put(bio);
8b712842
CM		 2947 return 0;
2948 }
2949
2950 /*
0986fe9e 2951 * nr_async_bios allows us to reliably return congestion to the
8b712842
CM		 2952 * higher layers. Otherwise, the async bio makes it appear we have
2953 * made progress against dirty pages when we've really just put it
2954 * on a queue for later
2955 */
0986fe9e 2956 atomic_inc(&root->fs_info->nr_async_bios);
492bb6de 2957 WARN_ON(bio->bi_next);
8b712842
CM		 2958 bio->bi_next = NULL;
2959 bio->bi_rw |= rw;
2960
2961 spin_lock(&device->io_lock);
1f98a13f 2962 if (bio_rw_flagged(bio, BIO_RW_SYNCIO))
ffbd517d
CM		 2963 pending_bios = &device->pending_sync_bios;
2964 else
2965 pending_bios = &device->pending_bios;
8b712842 2966
ffbd517d
CM		 2967 if (pending_bios->tail)
2968 pending_bios->tail->bi_next = bio;
8b712842 2969
ffbd517d
CM		 2970 pending_bios->tail = bio;
2971 if (!pending_bios->head)
2972 pending_bios->head = bio;
8b712842
CM		 2973 if (device->running_pending)
2974 should_queue = 0;
2975
2976 spin_unlock(&device->io_lock);
2977
2978 if (should_queue)
1cc127b5
CM		 2979 btrfs_queue_worker(&root->fs_info->submit_workers,
2980 &device->work);
8b712842
CM		 2981 return 0;
2982}
2983
f188591e 2984int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio,
8b712842 2985 int mirror_num, int async_submit)
0b86a832
CM		 2986{
2987 struct btrfs_mapping_tree *map_tree;
2988 struct btrfs_device *dev;
8790d502 2989 struct bio *first_bio = bio;
a62b9401 2990 u64 logical = (u64)bio->bi_sector << 9;
0b86a832
CM		 2991 u64 length = 0;
2992 u64 map_length;
cea9e445 2993 struct btrfs_multi_bio *multi = NULL;
0b86a832 2994 int ret;
8790d502
CM		 2995 int dev_nr = 0;
2996 int total_devs = 1;
0b86a832 2997
f2d8d74d 2998 length = bio->bi_size;
0b86a832
CM		 2999 map_tree = &root->fs_info->mapping_tree;
3000 map_length = length;
cea9e445 3001
f188591e
CM		 3002 ret = btrfs_map_block(map_tree, rw, logical, &map_length, &multi,
3003 mirror_num);
cea9e445
CM		 3004 BUG_ON(ret);
3005
3006 total_devs = multi->num_stripes;
3007 if (map_length < length) {
d397712b
CM		 3008 printk(KERN_CRIT "mapping failed logical %llu bio len %llu "
3009 "len %llu\n", (unsigned long long)logical,
3010 (unsigned long long)length,
3011 (unsigned long long)map_length);
cea9e445
CM		 3012 BUG();
3013 }
3014 multi->end_io = first_bio->bi_end_io;
3015 multi->private = first_bio->bi_private;
7d2b4daa 3016 multi->orig_bio = first_bio;
cea9e445
CM		 3017 atomic_set(&multi->stripes_pending, multi->num_stripes);
3018
d397712b 3019 while (dev_nr < total_devs) {
8790d502 3020 if (total_devs > 1) {
8790d502
CM		 3021 if (dev_nr < total_devs - 1) {
3022 bio = bio_clone(first_bio, GFP_NOFS);
3023 BUG_ON(!bio);
3024 } else {
3025 bio = first_bio;
3026 }
3027 bio->bi_private = multi;
3028 bio->bi_end_io = end_bio_multi_stripe;
3029 }
cea9e445
CM		 3030 bio->bi_sector = multi->stripes[dev_nr].physical >> 9;
3031 dev = multi->stripes[dev_nr].dev;
2b82032c 3032 BUG_ON(rw == WRITE && !dev->writeable);
dfe25020
CM		 3033 if (dev && dev->bdev) {
3034 bio->bi_bdev = dev->bdev;
8b712842
CM		 3035 if (async_submit)
3036 schedule_bio(root, dev, rw, bio);
3037 else
3038 submit_bio(rw, bio);
dfe25020
CM		 3039 } else {
3040 bio->bi_bdev = root->fs_info->fs_devices->latest_bdev;
3041 bio->bi_sector = logical >> 9;
dfe25020 3042 bio_endio(bio, -EIO);
dfe25020 3043 }
8790d502
CM		 3044 dev_nr++;
3045 }
cea9e445
CM		 3046 if (total_devs == 1)
3047 kfree(multi);
0b86a832
CM		 3048 return 0;
3049}
3050
a443755f 3051struct btrfs_device *btrfs_find_device(struct btrfs_root *root, u64 devid,
2b82032c 3052 u8 *uuid, u8 *fsid)
0b86a832 3053{
2b82032c
YZ		 3054 struct btrfs_device *device;
3055 struct btrfs_fs_devices *cur_devices;
3056
3057 cur_devices = root->fs_info->fs_devices;
3058 while (cur_devices) {
3059 if (!fsid ||
3060 !memcmp(cur_devices->fsid, fsid, BTRFS_UUID_SIZE)) {
3061 device = __find_device(&cur_devices->devices,
3062 devid, uuid);
3063 if (device)
3064 return device;
3065 }
3066 cur_devices = cur_devices->seed;
3067 }
3068 return NULL;
0b86a832
CM		 3069}
3070
dfe25020
CM		 3071static struct btrfs_device *add_missing_dev(struct btrfs_root *root,
3072 u64 devid, u8 *dev_uuid)
3073{
3074 struct btrfs_device *device;
3075 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
3076
3077 device = kzalloc(sizeof(*device), GFP_NOFS);
7cbd8a83 3078 if (!device)
3079 return NULL;
dfe25020
CM		 3080 list_add(&device->dev_list,
3081 &fs_devices->devices);
dfe25020
CM		 3082 device->barriers = 1;
3083 device->dev_root = root->fs_info->dev_root;
3084 device->devid = devid;
8b712842 3085 device->work.func = pending_bios_fn;
e4404d6e 3086 device->fs_devices = fs_devices;
dfe25020
CM		 3087 fs_devices->num_devices++;
3088 spin_lock_init(&device->io_lock);
d20f7043 3089 INIT_LIST_HEAD(&device->dev_alloc_list);
dfe25020
CM		 3090 memcpy(device->uuid, dev_uuid, BTRFS_UUID_SIZE);
3091 return device;
3092}
3093
0b86a832
CM		 3094static int read_one_chunk(struct btrfs_root *root, struct btrfs_key *key,
3095 struct extent_buffer *leaf,
3096 struct btrfs_chunk *chunk)
3097{
3098 struct btrfs_mapping_tree *map_tree = &root->fs_info->mapping_tree;
3099 struct map_lookup *map;
3100 struct extent_map *em;
3101 u64 logical;
3102 u64 length;
3103 u64 devid;
a443755f 3104 u8 uuid[BTRFS_UUID_SIZE];
593060d7 3105 int num_stripes;
0b86a832 3106 int ret;
593060d7 3107 int i;
0b86a832 3108
e17cade2
CM		 3109 logical = key->offset;
3110 length = btrfs_chunk_length(leaf, chunk);
a061fc8d 3111
890871be 3112 read_lock(&map_tree->map_tree.lock);
0b86a832 3113 em = lookup_extent_mapping(&map_tree->map_tree, logical, 1);
890871be 3114 read_unlock(&map_tree->map_tree.lock);
0b86a832
CM		 3115
3116 /* already mapped? */
3117 if (em && em->start <= logical && em->start + em->len > logical) {
3118 free_extent_map(em);
0b86a832
CM		 3119 return 0;
3120 } else if (em) {
3121 free_extent_map(em);
3122 }
0b86a832 3123
0b86a832
CM		 3124 em = alloc_extent_map(GFP_NOFS);
3125 if (!em)
3126 return -ENOMEM;
593060d7
CM		 3127 num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
3128 map = kmalloc(map_lookup_size(num_stripes), GFP_NOFS);
0b86a832
CM		 3129 if (!map) {
3130 free_extent_map(em);
3131 return -ENOMEM;
3132 }
3133
3134 em->bdev = (struct block_device *)map;
3135 em->start = logical;
3136 em->len = length;
3137 em->block_start = 0;
c8b97818 3138 em->block_len = em->len;
0b86a832 3139
593060d7
CM		 3140 map->num_stripes = num_stripes;
3141 map->io_width = btrfs_chunk_io_width(leaf, chunk);
3142 map->io_align = btrfs_chunk_io_align(leaf, chunk);
3143 map->sector_size = btrfs_chunk_sector_size(leaf, chunk);
3144 map->stripe_len = btrfs_chunk_stripe_len(leaf, chunk);
3145 map->type = btrfs_chunk_type(leaf, chunk);
321aecc6 3146 map->sub_stripes = btrfs_chunk_sub_stripes(leaf, chunk);
593060d7
CM		 3147 for (i = 0; i < num_stripes; i++) {
3148 map->stripes[i].physical =
3149 btrfs_stripe_offset_nr(leaf, chunk, i);
3150 devid = btrfs_stripe_devid_nr(leaf, chunk, i);
a443755f
CM		 3151 read_extent_buffer(leaf, uuid, (unsigned long)
3152 btrfs_stripe_dev_uuid_nr(chunk, i),
3153 BTRFS_UUID_SIZE);
2b82032c
YZ		 3154 map->stripes[i].dev = btrfs_find_device(root, devid, uuid,
3155 NULL);
dfe25020 3156 if (!map->stripes[i].dev && !btrfs_test_opt(root, DEGRADED)) {
593060d7
CM		 3157 kfree(map);
3158 free_extent_map(em);
3159 return -EIO;
3160 }
dfe25020
CM		 3161 if (!map->stripes[i].dev) {
3162 map->stripes[i].dev =
3163 add_missing_dev(root, devid, uuid);
3164 if (!map->stripes[i].dev) {
3165 kfree(map);
3166 free_extent_map(em);
3167 return -EIO;
3168 }
3169 }
3170 map->stripes[i].dev->in_fs_metadata = 1;
0b86a832
CM		 3171 }
3172
890871be 3173 write_lock(&map_tree->map_tree.lock);
0b86a832 3174 ret = add_extent_mapping(&map_tree->map_tree, em);
890871be 3175 write_unlock(&map_tree->map_tree.lock);
b248a415 3176 BUG_ON(ret);
0b86a832
CM		 3177 free_extent_map(em);
3178
3179 return 0;
3180}
3181
3182static int fill_device_from_item(struct extent_buffer *leaf,
3183 struct btrfs_dev_item *dev_item,
3184 struct btrfs_device *device)
3185{
3186 unsigned long ptr;
0b86a832
CM		 3187
3188 device->devid = btrfs_device_id(leaf, dev_item);
d6397bae
CB		 3189 device->disk_total_bytes = btrfs_device_total_bytes(leaf, dev_item);
3190 device->total_bytes = device->disk_total_bytes;
0b86a832
CM		 3191 device->bytes_used = btrfs_device_bytes_used(leaf, dev_item);
3192 device->type = btrfs_device_type(leaf, dev_item);
3193 device->io_align = btrfs_device_io_align(leaf, dev_item);
3194 device->io_width = btrfs_device_io_width(leaf, dev_item);
3195 device->sector_size = btrfs_device_sector_size(leaf, dev_item);
0b86a832
CM		 3196
3197 ptr = (unsigned long)btrfs_device_uuid(dev_item);
e17cade2 3198 read_extent_buffer(leaf, device->uuid, ptr, BTRFS_UUID_SIZE);
0b86a832 3199
0b86a832
CM		 3200 return 0;
3201}
3202
2b82032c
YZ		 3203static int open_seed_devices(struct btrfs_root *root, u8 *fsid)
3204{
3205 struct btrfs_fs_devices *fs_devices;
3206 int ret;
3207
3208 mutex_lock(&uuid_mutex);
3209
3210 fs_devices = root->fs_info->fs_devices->seed;
3211 while (fs_devices) {
3212 if (!memcmp(fs_devices->fsid, fsid, BTRFS_UUID_SIZE)) {
3213 ret = 0;
3214 goto out;
3215 }
3216 fs_devices = fs_devices->seed;
3217 }
3218
3219 fs_devices = find_fsid(fsid);
3220 if (!fs_devices) {
3221 ret = -ENOENT;
3222 goto out;
3223 }
e4404d6e
YZ		 3224
3225 fs_devices = clone_fs_devices(fs_devices);
3226 if (IS_ERR(fs_devices)) {
3227 ret = PTR_ERR(fs_devices);
2b82032c
YZ		 3228 goto out;
3229 }
3230
97288f2c 3231 ret = __btrfs_open_devices(fs_devices, FMODE_READ,
15916de8 3232 root->fs_info->bdev_holder);
2b82032c
YZ		 3233 if (ret)
3234 goto out;
3235
3236 if (!fs_devices->seeding) {
3237 __btrfs_close_devices(fs_devices);
e4404d6e 3238 free_fs_devices(fs_devices);
2b82032c
YZ		 3239 ret = -EINVAL;
3240 goto out;
3241 }
3242
3243 fs_devices->seed = root->fs_info->fs_devices->seed;
3244 root->fs_info->fs_devices->seed = fs_devices;
2b82032c
YZ		 3245out:
3246 mutex_unlock(&uuid_mutex);
3247 return ret;
3248}
3249
0d81ba5d 3250static int read_one_dev(struct btrfs_root *root,
0b86a832
CM		 3251 struct extent_buffer *leaf,
3252 struct btrfs_dev_item *dev_item)
3253{
3254 struct btrfs_device *device;
3255 u64 devid;
3256 int ret;
2b82032c 3257 u8 fs_uuid[BTRFS_UUID_SIZE];
a443755f
CM		 3258 u8 dev_uuid[BTRFS_UUID_SIZE];
3259
0b86a832 3260 devid = btrfs_device_id(leaf, dev_item);
a443755f
CM		 3261 read_extent_buffer(leaf, dev_uuid,
3262 (unsigned long)btrfs_device_uuid(dev_item),
3263 BTRFS_UUID_SIZE);
2b82032c
YZ		 3264 read_extent_buffer(leaf, fs_uuid,
3265 (unsigned long)btrfs_device_fsid(dev_item),
3266 BTRFS_UUID_SIZE);
3267
3268 if (memcmp(fs_uuid, root->fs_info->fsid, BTRFS_UUID_SIZE)) {
3269 ret = open_seed_devices(root, fs_uuid);
e4404d6e 3270 if (ret && !btrfs_test_opt(root, DEGRADED))
2b82032c 3271 return ret;
2b82032c
YZ		 3272 }
3273
3274 device = btrfs_find_device(root, devid, dev_uuid, fs_uuid);
3275 if (!device || !device->bdev) {
e4404d6e 3276 if (!btrfs_test_opt(root, DEGRADED))
2b82032c
YZ		 3277 return -EIO;
3278
3279 if (!device) {
d397712b
CM		 3280 printk(KERN_WARNING "warning devid %llu missing\n",
3281 (unsigned long long)devid);
2b82032c
YZ		 3282 device = add_missing_dev(root, devid, dev_uuid);
3283 if (!device)
3284 return -ENOMEM;
3285 }
3286 }
3287
3288 if (device->fs_devices != root->fs_info->fs_devices) {
3289 BUG_ON(device->writeable);
3290 if (device->generation !=
3291 btrfs_device_generation(leaf, dev_item))
3292 return -EINVAL;
6324fbf3 3293 }
0b86a832
CM		 3294
3295 fill_device_from_item(leaf, dev_item, device);
3296 device->dev_root = root->fs_info->dev_root;
dfe25020 3297 device->in_fs_metadata = 1;
2b82032c
YZ		 3298 if (device->writeable)
3299 device->fs_devices->total_rw_bytes += device->total_bytes;
0b86a832 3300 ret = 0;
0b86a832
CM		 3301 return ret;
3302}
3303
0d81ba5d
CM		 3304int btrfs_read_super_device(struct btrfs_root *root, struct extent_buffer *buf)
3305{
3306 struct btrfs_dev_item *dev_item;
3307
3308 dev_item = (struct btrfs_dev_item *)offsetof(struct btrfs_super_block,
3309 dev_item);
3310 return read_one_dev(root, buf, dev_item);
3311}
3312
e4404d6e 3313int btrfs_read_sys_array(struct btrfs_root *root)
0b86a832
CM		 3314{
3315 struct btrfs_super_block *super_copy = &root->fs_info->super_copy;
a061fc8d 3316 struct extent_buffer *sb;
0b86a832 3317 struct btrfs_disk_key *disk_key;
0b86a832 3318 struct btrfs_chunk *chunk;
84eed90f
CM		 3319 u8 *ptr;
3320 unsigned long sb_ptr;
3321 int ret = 0;
0b86a832
CM		 3322 u32 num_stripes;
3323 u32 array_size;
3324 u32 len = 0;
0b86a832 3325 u32 cur;
84eed90f 3326 struct btrfs_key key;
0b86a832 3327
e4404d6e 3328 sb = btrfs_find_create_tree_block(root, BTRFS_SUPER_INFO_OFFSET,
a061fc8d
CM		 3329 BTRFS_SUPER_INFO_SIZE);
3330 if (!sb)
3331 return -ENOMEM;
3332 btrfs_set_buffer_uptodate(sb);
4008c04a
CM		 3333 btrfs_set_buffer_lockdep_class(sb, 0);
3334
a061fc8d 3335 write_extent_buffer(sb, super_copy, 0, BTRFS_SUPER_INFO_SIZE);
0b86a832
CM		 3336 array_size = btrfs_super_sys_array_size(super_copy);
3337
0b86a832
CM		 3338 ptr = super_copy->sys_chunk_array;
3339 sb_ptr = offsetof(struct btrfs_super_block, sys_chunk_array);
3340 cur = 0;
3341
3342 while (cur < array_size) {
3343 disk_key = (struct btrfs_disk_key *)ptr;
3344 btrfs_disk_key_to_cpu(&key, disk_key);
3345
a061fc8d 3346 len = sizeof(*disk_key); ptr += len;
0b86a832
CM		 3347 sb_ptr += len;
3348 cur += len;
3349
0d81ba5d 3350 if (key.type == BTRFS_CHUNK_ITEM_KEY) {
0b86a832 3351 chunk = (struct btrfs_chunk *)sb_ptr;
0d81ba5d 3352 ret = read_one_chunk(root, &key, sb, chunk);
84eed90f
CM		 3353 if (ret)
3354 break;
0b86a832
CM		 3355 num_stripes = btrfs_chunk_num_stripes(sb, chunk);
3356 len = btrfs_chunk_item_size(num_stripes);
3357 } else {
84eed90f
CM		 3358 ret = -EIO;
3359 break;
0b86a832
CM		 3360 }
3361 ptr += len;
3362 sb_ptr += len;
3363 cur += len;
3364 }
a061fc8d 3365 free_extent_buffer(sb);
84eed90f 3366 return ret;
0b86a832
CM		 3367}
3368
3369int btrfs_read_chunk_tree(struct btrfs_root *root)
3370{
3371 struct btrfs_path *path;
3372 struct extent_buffer *leaf;
3373 struct btrfs_key key;
3374 struct btrfs_key found_key;
3375 int ret;
3376 int slot;
3377
3378 root = root->fs_info->chunk_root;
3379
3380 path = btrfs_alloc_path();
3381 if (!path)
3382 return -ENOMEM;
3383
3384 /* first we search for all of the device items, and then we
3385 * read in all of the chunk items. This way we can create chunk
3386 * mappings that reference all of the devices that are afound
3387 */
3388 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
3389 key.offset = 0;
3390 key.type = 0;
3391again:
3392 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
d397712b 3393 while (1) {
0b86a832
CM		 3394 leaf = path->nodes[0];
3395 slot = path->slots[0];
3396 if (slot >= btrfs_header_nritems(leaf)) {
3397 ret = btrfs_next_leaf(root, path);
3398 if (ret == 0)
3399 continue;
3400 if (ret < 0)
3401 goto error;
3402 break;
3403 }
3404 btrfs_item_key_to_cpu(leaf, &found_key, slot);
3405 if (key.objectid == BTRFS_DEV_ITEMS_OBJECTID) {
3406 if (found_key.objectid != BTRFS_DEV_ITEMS_OBJECTID)
3407 break;
3408 if (found_key.type == BTRFS_DEV_ITEM_KEY) {
3409 struct btrfs_dev_item *dev_item;
3410 dev_item = btrfs_item_ptr(leaf, slot,
3411 struct btrfs_dev_item);
0d81ba5d 3412 ret = read_one_dev(root, leaf, dev_item);
2b82032c
YZ		 3413 if (ret)
3414 goto error;
0b86a832
CM		 3415 }
3416 } else if (found_key.type == BTRFS_CHUNK_ITEM_KEY) {
3417 struct btrfs_chunk *chunk;
3418 chunk = btrfs_item_ptr(leaf, slot, struct btrfs_chunk);
3419 ret = read_one_chunk(root, &found_key, leaf, chunk);
2b82032c
YZ		 3420 if (ret)
3421 goto error;
0b86a832
CM		 3422 }
3423 path->slots[0]++;
3424 }
3425 if (key.objectid == BTRFS_DEV_ITEMS_OBJECTID) {
3426 key.objectid = 0;
3427 btrfs_release_path(root, path);
3428 goto again;
3429 }
0b86a832
CM		 3430 ret = 0;
3431error:
2b82032c 3432 btrfs_free_path(path);
0b86a832
CM		 3433 return ret;
3434}
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