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Fix gcc 4.5.1 miscompiling drivers/char/i8k.c (again)
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / fs / btrfs / volumes.c
blob41ecbb2347f2d3171f7645782ab4e5a39621c84d
1 /*
2 * Copyright (C) 2007 Oracle. All rights reserved.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public
6 * License v2 as published by the Free Software Foundation.
7 *
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
12 *
13 * You should have received a copy of the GNU General Public
14 * License along with this program; if not, write to the
15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
16 * Boston, MA 021110-1307, USA.
17 */
18 #include <linux/sched.h>
19 #include <linux/bio.h>
20 #include <linux/buffer_head.h>
21 #include <linux/blkdev.h>
22 #include <linux/random.h>
23 #include <linux/iocontext.h>
24 #include <asm/div64.h>
25 #include "compat.h"
26 #include "ctree.h"
27 #include "extent_map.h"
28 #include "disk-io.h"
29 #include "transaction.h"
30 #include "print-tree.h"
31 #include "volumes.h"
32 #include "async-thread.h"
33
34 struct map_lookup {
35 u64 type;
36 int io_align;
37 int io_width;
38 int stripe_len;
39 int sector_size;
40 int num_stripes;
41 int sub_stripes;
42 struct btrfs_bio_stripe stripes[];
43 };
44
45 static int init_first_rw_device(struct btrfs_trans_handle *trans,
46 struct btrfs_root *root,
47 struct btrfs_device *device);
48 static int btrfs_relocate_sys_chunks(struct btrfs_root *root);
49
50 #define map_lookup_size(n) (sizeof(struct map_lookup) + \
51 (sizeof(struct btrfs_bio_stripe) * (n)))
52
53 static DEFINE_MUTEX(uuid_mutex);
54 static LIST_HEAD(fs_uuids);
55
56 void btrfs_lock_volumes(void)
57 {
58 mutex_lock(&uuid_mutex);
59 }
60
61 void btrfs_unlock_volumes(void)
62 {
63 mutex_unlock(&uuid_mutex);
64 }
65
66 static void lock_chunks(struct btrfs_root *root)
67 {
68 mutex_lock(&root->fs_info->chunk_mutex);
69 }
70
71 static void unlock_chunks(struct btrfs_root *root)
72 {
73 mutex_unlock(&root->fs_info->chunk_mutex);
74 }
75
76 static void free_fs_devices(struct btrfs_fs_devices *fs_devices)
77 {
78 struct btrfs_device *device;
79 WARN_ON(fs_devices->opened);
80 while (!list_empty(&fs_devices->devices)) {
81 device = list_entry(fs_devices->devices.next,
82 struct btrfs_device, dev_list);
83 list_del(&device->dev_list);
84 kfree(device->name);
85 kfree(device);
86 }
87 kfree(fs_devices);
88 }
89
90 int btrfs_cleanup_fs_uuids(void)
91 {
92 struct btrfs_fs_devices *fs_devices;
93
94 while (!list_empty(&fs_uuids)) {
95 fs_devices = list_entry(fs_uuids.next,
96 struct btrfs_fs_devices, list);
97 list_del(&fs_devices->list);
98 free_fs_devices(fs_devices);
99 }
100 return 0;
101 }
102
103 static noinline struct btrfs_device *__find_device(struct list_head *head,
104 u64 devid, u8 *uuid)
105 {
106 struct btrfs_device *dev;
107
108 list_for_each_entry(dev, head, dev_list) {
109 if (dev->devid == devid &&
110 (!uuid || !memcmp(dev->uuid, uuid, BTRFS_UUID_SIZE))) {
111 return dev;
112 }
113 }
114 return NULL;
115 }
116
117 static noinline struct btrfs_fs_devices *find_fsid(u8 *fsid)
118 {
119 struct btrfs_fs_devices *fs_devices;
120
121 list_for_each_entry(fs_devices, &fs_uuids, list) {
122 if (memcmp(fsid, fs_devices->fsid, BTRFS_FSID_SIZE) == 0)
123 return fs_devices;
124 }
125 return NULL;
126 }
127
128 static void requeue_list(struct btrfs_pending_bios *pending_bios,
129 struct bio *head, struct bio *tail)
130 {
131
132 struct bio *old_head;
133
134 old_head = pending_bios->head;
135 pending_bios->head = head;
136 if (pending_bios->tail)
137 tail->bi_next = old_head;
138 else
139 pending_bios->tail = tail;
140 }
141
142 /*
143 * we try to collect pending bios for a device so we don't get a large
144 * number of procs sending bios down to the same device. This greatly
145 * improves the schedulers ability to collect and merge the bios.
146 *
147 * But, it also turns into a long list of bios to process and that is sure
148 * to eventually make the worker thread block. The solution here is to
149 * make some progress and then put this work struct back at the end of
150 * the list if the block device is congested. This way, multiple devices
151 * can make progress from a single worker thread.
152 */
153 static noinline int run_scheduled_bios(struct btrfs_device *device)
154 {
155 struct bio *pending;
156 struct backing_dev_info *bdi;
157 struct btrfs_fs_info *fs_info;
158 struct btrfs_pending_bios *pending_bios;
159 struct bio *tail;
160 struct bio *cur;
161 int again = 0;
162 unsigned long num_run;
163 unsigned long num_sync_run;
164 unsigned long batch_run = 0;
165 unsigned long limit;
166 unsigned long last_waited = 0;
167 int force_reg = 0;
168
169 bdi = blk_get_backing_dev_info(device->bdev);
170 fs_info = device->dev_root->fs_info;
171 limit = btrfs_async_submit_limit(fs_info);
172 limit = limit * 2 / 3;
173
174 /* we want to make sure that every time we switch from the sync
175 * list to the normal list, we unplug
176 */
177 num_sync_run = 0;
178
179 loop:
180 spin_lock(&device->io_lock);
181
182 loop_lock:
183 num_run = 0;
184
185 /* take all the bios off the list at once and process them
186 * later on (without the lock held). But, remember the
187 * tail and other pointers so the bios can be properly reinserted
188 * into the list if we hit congestion
189 */
190 if (!force_reg && device->pending_sync_bios.head) {
191 pending_bios = &device->pending_sync_bios;
192 force_reg = 1;
193 } else {
194 pending_bios = &device->pending_bios;
195 force_reg = 0;
196 }
197
198 pending = pending_bios->head;
199 tail = pending_bios->tail;
200 WARN_ON(pending && !tail);
201
202 /*
203 * if pending was null this time around, no bios need processing
204 * at all and we can stop. Otherwise it'll loop back up again
205 * and do an additional check so no bios are missed.
206 *
207 * device->running_pending is used to synchronize with the
208 * schedule_bio code.
209 */
210 if (device->pending_sync_bios.head == NULL &&
211 device->pending_bios.head == NULL) {
212 again = 0;
213 device->running_pending = 0;
214 } else {
215 again = 1;
216 device->running_pending = 1;
217 }
218
219 pending_bios->head = NULL;
220 pending_bios->tail = NULL;
221
222 spin_unlock(&device->io_lock);
223
224 /*
225 * if we're doing the regular priority list, make sure we unplug
226 * for any high prio bios we've sent down
227 */
228 if (pending_bios == &device->pending_bios && num_sync_run > 0) {
229 num_sync_run = 0;
230 blk_run_backing_dev(bdi, NULL);
231 }
232
233 while (pending) {
234
235 rmb();
236 /* we want to work on both lists, but do more bios on the
237 * sync list than the regular list
238 */
239 if ((num_run > 32 &&
240 pending_bios != &device->pending_sync_bios &&
241 device->pending_sync_bios.head) ||
242 (num_run > 64 && pending_bios == &device->pending_sync_bios &&
243 device->pending_bios.head)) {
244 spin_lock(&device->io_lock);
245 requeue_list(pending_bios, pending, tail);
246 goto loop_lock;
247 }
248
249 cur = pending;
250 pending = pending->bi_next;
251 cur->bi_next = NULL;
252 atomic_dec(&fs_info->nr_async_bios);
253
254 if (atomic_read(&fs_info->nr_async_bios) < limit &&
255 waitqueue_active(&fs_info->async_submit_wait))
256 wake_up(&fs_info->async_submit_wait);
257
258 BUG_ON(atomic_read(&cur->bi_cnt) == 0);
259 submit_bio(cur->bi_rw, cur);
260 num_run++;
261 batch_run++;
262
263 if (bio_rw_flagged(cur, BIO_RW_SYNCIO))
264 num_sync_run++;
265
266 if (need_resched()) {
267 if (num_sync_run) {
268 blk_run_backing_dev(bdi, NULL);
269 num_sync_run = 0;
270 }
271 cond_resched();
272 }
273
274 /*
275 * we made progress, there is more work to do and the bdi
276 * is now congested. Back off and let other work structs
277 * run instead
278 */
279 if (pending && bdi_write_congested(bdi) && batch_run > 8 &&
280 fs_info->fs_devices->open_devices > 1) {
281 struct io_context *ioc;
282
283 ioc = current->io_context;
284
285 /*
286 * the main goal here is that we don't want to
287 * block if we're going to be able to submit
288 * more requests without blocking.
289 *
290 * This code does two great things, it pokes into
291 * the elevator code from a filesystem _and_
292 * it makes assumptions about how batching works.
293 */
294 if (ioc && ioc->nr_batch_requests > 0 &&
295 time_before(jiffies, ioc->last_waited + HZ/50UL) &&
296 (last_waited == 0 ||
297 ioc->last_waited == last_waited)) {
298 /*
299 * we want to go through our batch of
300 * requests and stop. So, we copy out
301 * the ioc->last_waited time and test
302 * against it before looping
303 */
304 last_waited = ioc->last_waited;
305 if (need_resched()) {
306 if (num_sync_run) {
307 blk_run_backing_dev(bdi, NULL);
308 num_sync_run = 0;
309 }
310 cond_resched();
311 }
312 continue;
313 }
314 spin_lock(&device->io_lock);
315 requeue_list(pending_bios, pending, tail);
316 device->running_pending = 1;
317
318 spin_unlock(&device->io_lock);
319 btrfs_requeue_work(&device->work);
320 goto done;
321 }
322 }
323
324 if (num_sync_run) {
325 num_sync_run = 0;
326 blk_run_backing_dev(bdi, NULL);
327 }
328
329 cond_resched();
330 if (again)
331 goto loop;
332
333 spin_lock(&device->io_lock);
334 if (device->pending_bios.head || device->pending_sync_bios.head)
335 goto loop_lock;
336 spin_unlock(&device->io_lock);
337
338 /*
339 * IO has already been through a long path to get here. Checksumming,
340 * async helper threads, perhaps compression. We've done a pretty
341 * good job of collecting a batch of IO and should just unplug
342 * the device right away.
343 *
344 * This will help anyone who is waiting on the IO, they might have
345 * already unplugged, but managed to do so before the bio they
346 * cared about found its way down here.
347 */
348 blk_run_backing_dev(bdi, NULL);
349 done:
350 return 0;
351 }
352
353 static void pending_bios_fn(struct btrfs_work *work)
354 {
355 struct btrfs_device *device;
356
357 device = container_of(work, struct btrfs_device, work);
358 run_scheduled_bios(device);
359 }
360
361 static noinline int device_list_add(const char *path,
362 struct btrfs_super_block *disk_super,
363 u64 devid, struct btrfs_fs_devices **fs_devices_ret)
364 {
365 struct btrfs_device *device;
366 struct btrfs_fs_devices *fs_devices;
367 u64 found_transid = btrfs_super_generation(disk_super);
368
369 fs_devices = find_fsid(disk_super->fsid);
370 if (!fs_devices) {
371 fs_devices = kzalloc(sizeof(*fs_devices), GFP_NOFS);
372 if (!fs_devices)
373 return -ENOMEM;
374 INIT_LIST_HEAD(&fs_devices->devices);
375 INIT_LIST_HEAD(&fs_devices->alloc_list);
376 list_add(&fs_devices->list, &fs_uuids);
377 memcpy(fs_devices->fsid, disk_super->fsid, BTRFS_FSID_SIZE);
378 fs_devices->latest_devid = devid;
379 fs_devices->latest_trans = found_transid;
380 mutex_init(&fs_devices->device_list_mutex);
381 device = NULL;
382 } else {
383 device = __find_device(&fs_devices->devices, devid,
384 disk_super->dev_item.uuid);
385 }
386 if (!device) {
387 if (fs_devices->opened)
388 return -EBUSY;
389
390 device = kzalloc(sizeof(*device), GFP_NOFS);
391 if (!device) {
392 /* we can safely leave the fs_devices entry around */
393 return -ENOMEM;
394 }
395 device->devid = devid;
396 device->work.func = pending_bios_fn;
397 memcpy(device->uuid, disk_super->dev_item.uuid,
398 BTRFS_UUID_SIZE);
399 device->barriers = 1;
400 spin_lock_init(&device->io_lock);
401 device->name = kstrdup(path, GFP_NOFS);
402 if (!device->name) {
403 kfree(device);
404 return -ENOMEM;
405 }
406 INIT_LIST_HEAD(&device->dev_alloc_list);
407
408 mutex_lock(&fs_devices->device_list_mutex);
409 list_add(&device->dev_list, &fs_devices->devices);
410 mutex_unlock(&fs_devices->device_list_mutex);
411
412 device->fs_devices = fs_devices;
413 fs_devices->num_devices++;
414 }
415
416 if (found_transid > fs_devices->latest_trans) {
417 fs_devices->latest_devid = devid;
418 fs_devices->latest_trans = found_transid;
419 }
420 *fs_devices_ret = fs_devices;
421 return 0;
422 }
423
424 static struct btrfs_fs_devices *clone_fs_devices(struct btrfs_fs_devices *orig)
425 {
426 struct btrfs_fs_devices *fs_devices;
427 struct btrfs_device *device;
428 struct btrfs_device *orig_dev;
429
430 fs_devices = kzalloc(sizeof(*fs_devices), GFP_NOFS);
431 if (!fs_devices)
432 return ERR_PTR(-ENOMEM);
433
434 INIT_LIST_HEAD(&fs_devices->devices);
435 INIT_LIST_HEAD(&fs_devices->alloc_list);
436 INIT_LIST_HEAD(&fs_devices->list);
437 mutex_init(&fs_devices->device_list_mutex);
438 fs_devices->latest_devid = orig->latest_devid;
439 fs_devices->latest_trans = orig->latest_trans;
440 memcpy(fs_devices->fsid, orig->fsid, sizeof(fs_devices->fsid));
441
442 mutex_lock(&orig->device_list_mutex);
443 list_for_each_entry(orig_dev, &orig->devices, dev_list) {
444 device = kzalloc(sizeof(*device), GFP_NOFS);
445 if (!device)
446 goto error;
447
448 device->name = kstrdup(orig_dev->name, GFP_NOFS);
449 if (!device->name) {
450 kfree(device);
451 goto error;
452 }
453
454 device->devid = orig_dev->devid;
455 device->work.func = pending_bios_fn;
456 memcpy(device->uuid, orig_dev->uuid, sizeof(device->uuid));
457 device->barriers = 1;
458 spin_lock_init(&device->io_lock);
459 INIT_LIST_HEAD(&device->dev_list);
460 INIT_LIST_HEAD(&device->dev_alloc_list);
461
462 list_add(&device->dev_list, &fs_devices->devices);
463 device->fs_devices = fs_devices;
464 fs_devices->num_devices++;
465 }
466 mutex_unlock(&orig->device_list_mutex);
467 return fs_devices;
468 error:
469 mutex_unlock(&orig->device_list_mutex);
470 free_fs_devices(fs_devices);
471 return ERR_PTR(-ENOMEM);
472 }
473
474 int btrfs_close_extra_devices(struct btrfs_fs_devices *fs_devices)
475 {
476 struct btrfs_device *device, *next;
477
478 mutex_lock(&uuid_mutex);
479 again:
480 mutex_lock(&fs_devices->device_list_mutex);
481 list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) {
482 if (device->in_fs_metadata)
483 continue;
484
485 if (device->bdev) {
486 close_bdev_exclusive(device->bdev, device->mode);
487 device->bdev = NULL;
488 fs_devices->open_devices--;
489 }
490 if (device->writeable) {
491 list_del_init(&device->dev_alloc_list);
492 device->writeable = 0;
493 fs_devices->rw_devices--;
494 }
495 list_del_init(&device->dev_list);
496 fs_devices->num_devices--;
497 kfree(device->name);
498 kfree(device);
499 }
500 mutex_unlock(&fs_devices->device_list_mutex);
501
502 if (fs_devices->seed) {
503 fs_devices = fs_devices->seed;
504 goto again;
505 }
506
507 mutex_unlock(&uuid_mutex);
508 return 0;
509 }
510
511 static int __btrfs_close_devices(struct btrfs_fs_devices *fs_devices)
512 {
513 struct btrfs_device *device;
514
515 if (--fs_devices->opened > 0)
516 return 0;
517
518 list_for_each_entry(device, &fs_devices->devices, dev_list) {
519 if (device->bdev) {
520 close_bdev_exclusive(device->bdev, device->mode);
521 fs_devices->open_devices--;
522 }
523 if (device->writeable) {
524 list_del_init(&device->dev_alloc_list);
525 fs_devices->rw_devices--;
526 }
527
528 device->bdev = NULL;
529 device->writeable = 0;
530 device->in_fs_metadata = 0;
531 }
532 WARN_ON(fs_devices->open_devices);
533 WARN_ON(fs_devices->rw_devices);
534 fs_devices->opened = 0;
535 fs_devices->seeding = 0;
536
537 return 0;
538 }
539
540 int btrfs_close_devices(struct btrfs_fs_devices *fs_devices)
541 {
542 struct btrfs_fs_devices *seed_devices = NULL;
543 int ret;
544
545 mutex_lock(&uuid_mutex);
546 ret = __btrfs_close_devices(fs_devices);
547 if (!fs_devices->opened) {
548 seed_devices = fs_devices->seed;
549 fs_devices->seed = NULL;
550 }
551 mutex_unlock(&uuid_mutex);
552
553 while (seed_devices) {
554 fs_devices = seed_devices;
555 seed_devices = fs_devices->seed;
556 __btrfs_close_devices(fs_devices);
557 free_fs_devices(fs_devices);
558 }
559 return ret;
560 }
561
562 static int __btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
563 fmode_t flags, void *holder)
564 {
565 struct block_device *bdev;
566 struct list_head *head = &fs_devices->devices;
567 struct btrfs_device *device;
568 struct block_device *latest_bdev = NULL;
569 struct buffer_head *bh;
570 struct btrfs_super_block *disk_super;
571 u64 latest_devid = 0;
572 u64 latest_transid = 0;
573 u64 devid;
574 int seeding = 1;
575 int ret = 0;
576
577 list_for_each_entry(device, head, dev_list) {
578 if (device->bdev)
579 continue;
580 if (!device->name)
581 continue;
582
583 bdev = open_bdev_exclusive(device->name, flags, holder);
584 if (IS_ERR(bdev)) {
585 printk(KERN_INFO "open %s failed\n", device->name);
586 goto error;
587 }
588 set_blocksize(bdev, 4096);
589
590 bh = btrfs_read_dev_super(bdev);
591 if (!bh)
592 goto error_close;
593
594 disk_super = (struct btrfs_super_block *)bh->b_data;
595 devid = le64_to_cpu(disk_super->dev_item.devid);
596 if (devid != device->devid)
597 goto error_brelse;
598
599 if (memcmp(device->uuid, disk_super->dev_item.uuid,
600 BTRFS_UUID_SIZE))
601 goto error_brelse;
602
603 device->generation = btrfs_super_generation(disk_super);
604 if (!latest_transid || device->generation > latest_transid) {
605 latest_devid = devid;
606 latest_transid = device->generation;
607 latest_bdev = bdev;
608 }
609
610 if (btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_SEEDING) {
611 device->writeable = 0;
612 } else {
613 device->writeable = !bdev_read_only(bdev);
614 seeding = 0;
615 }
616
617 device->bdev = bdev;
618 device->in_fs_metadata = 0;
619 device->mode = flags;
620
621 if (!blk_queue_nonrot(bdev_get_queue(bdev)))
622 fs_devices->rotating = 1;
623
624 fs_devices->open_devices++;
625 if (device->writeable) {
626 fs_devices->rw_devices++;
627 list_add(&device->dev_alloc_list,
628 &fs_devices->alloc_list);
629 }
630 continue;
631
632 error_brelse:
633 brelse(bh);
634 error_close:
635 close_bdev_exclusive(bdev, FMODE_READ);
636 error:
637 continue;
638 }
639 if (fs_devices->open_devices == 0) {
640 ret = -EIO;
641 goto out;
642 }
643 fs_devices->seeding = seeding;
644 fs_devices->opened = 1;
645 fs_devices->latest_bdev = latest_bdev;
646 fs_devices->latest_devid = latest_devid;
647 fs_devices->latest_trans = latest_transid;
648 fs_devices->total_rw_bytes = 0;
649 out:
650 return ret;
651 }
652
653 int btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
654 fmode_t flags, void *holder)
655 {
656 int ret;
657
658 mutex_lock(&uuid_mutex);
659 if (fs_devices->opened) {
660 fs_devices->opened++;
661 ret = 0;
662 } else {
663 ret = __btrfs_open_devices(fs_devices, flags, holder);
664 }
665 mutex_unlock(&uuid_mutex);
666 return ret;
667 }
668
669 int btrfs_scan_one_device(const char *path, fmode_t flags, void *holder,
670 struct btrfs_fs_devices **fs_devices_ret)
671 {
672 struct btrfs_super_block *disk_super;
673 struct block_device *bdev;
674 struct buffer_head *bh;
675 int ret;
676 u64 devid;
677 u64 transid;
678
679 mutex_lock(&uuid_mutex);
680
681 bdev = open_bdev_exclusive(path, flags, holder);
682
683 if (IS_ERR(bdev)) {
684 ret = PTR_ERR(bdev);
685 goto error;
686 }
687
688 ret = set_blocksize(bdev, 4096);
689 if (ret)
690 goto error_close;
691 bh = btrfs_read_dev_super(bdev);
692 if (!bh) {
693 ret = -EIO;
694 goto error_close;
695 }
696 disk_super = (struct btrfs_super_block *)bh->b_data;
697 devid = le64_to_cpu(disk_super->dev_item.devid);
698 transid = btrfs_super_generation(disk_super);
699 if (disk_super->label[0])
700 printk(KERN_INFO "device label %s ", disk_super->label);
701 else {
702 /* FIXME, make a readl uuid parser */
703 printk(KERN_INFO "device fsid %llx-%llx ",
704 *(unsigned long long *)disk_super->fsid,
705 *(unsigned long long *)(disk_super->fsid + 8));
706 }
707 printk(KERN_CONT "devid %llu transid %llu %s\n",
708 (unsigned long long)devid, (unsigned long long)transid, path);
709 ret = device_list_add(path, disk_super, devid, fs_devices_ret);
710
711 brelse(bh);
712 error_close:
713 close_bdev_exclusive(bdev, flags);
714 error:
715 mutex_unlock(&uuid_mutex);
716 return ret;
717 }
718
719 /*
720 * this uses a pretty simple search, the expectation is that it is
721 * called very infrequently and that a given device has a small number
722 * of extents
723 */
724 int find_free_dev_extent(struct btrfs_trans_handle *trans,
725 struct btrfs_device *device, u64 num_bytes,
726 u64 *start, u64 *max_avail)
727 {
728 struct btrfs_key key;
729 struct btrfs_root *root = device->dev_root;
730 struct btrfs_dev_extent *dev_extent = NULL;
731 struct btrfs_path *path;
732 u64 hole_size = 0;
733 u64 last_byte = 0;
734 u64 search_start = 0;
735 u64 search_end = device->total_bytes;
736 int ret;
737 int slot = 0;
738 int start_found;
739 struct extent_buffer *l;
740
741 path = btrfs_alloc_path();
742 if (!path)
743 return -ENOMEM;
744 path->reada = 2;
745 start_found = 0;
746
747 /* FIXME use last free of some kind */
748
749 /* we don't want to overwrite the superblock on the drive,
750 * so we make sure to start at an offset of at least 1MB
751 */
752 search_start = max((u64)1024 * 1024, search_start);
753
754 if (root->fs_info->alloc_start + num_bytes <= device->total_bytes)
755 search_start = max(root->fs_info->alloc_start, search_start);
756
757 key.objectid = device->devid;
758 key.offset = search_start;
759 key.type = BTRFS_DEV_EXTENT_KEY;
760 ret = btrfs_search_slot(trans, root, &key, path, 0, 0);
761 if (ret < 0)
762 goto error;
763 if (ret > 0) {
764 ret = btrfs_previous_item(root, path, key.objectid, key.type);
765 if (ret < 0)
766 goto error;
767 if (ret > 0)
768 start_found = 1;
769 }
770 l = path->nodes[0];
771 btrfs_item_key_to_cpu(l, &key, path->slots[0]);
772 while (1) {
773 l = path->nodes[0];
774 slot = path->slots[0];
775 if (slot >= btrfs_header_nritems(l)) {
776 ret = btrfs_next_leaf(root, path);
777 if (ret == 0)
778 continue;
779 if (ret < 0)
780 goto error;
781 no_more_items:
782 if (!start_found) {
783 if (search_start >= search_end) {
784 ret = -ENOSPC;
785 goto error;
786 }
787 *start = search_start;
788 start_found = 1;
789 goto check_pending;
790 }
791 *start = last_byte > search_start ?
792 last_byte : search_start;
793 if (search_end <= *start) {
794 ret = -ENOSPC;
795 goto error;
796 }
797 goto check_pending;
798 }
799 btrfs_item_key_to_cpu(l, &key, slot);
800
801 if (key.objectid < device->devid)
802 goto next;
803
804 if (key.objectid > device->devid)
805 goto no_more_items;
806
807 if (key.offset >= search_start && key.offset > last_byte &&
808 start_found) {
809 if (last_byte < search_start)
810 last_byte = search_start;
811 hole_size = key.offset - last_byte;
812
813 if (hole_size > *max_avail)
814 *max_avail = hole_size;
815
816 if (key.offset > last_byte &&
817 hole_size >= num_bytes) {
818 *start = last_byte;
819 goto check_pending;
820 }
821 }
822 if (btrfs_key_type(&key) != BTRFS_DEV_EXTENT_KEY)
823 goto next;
824
825 start_found = 1;
826 dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent);
827 last_byte = key.offset + btrfs_dev_extent_length(l, dev_extent);
828 next:
829 path->slots[0]++;
830 cond_resched();
831 }
832 check_pending:
833 /* we have to make sure we didn't find an extent that has already
834 * been allocated by the map tree or the original allocation
835 */
836 BUG_ON(*start < search_start);
837
838 if (*start + num_bytes > search_end) {
839 ret = -ENOSPC;
840 goto error;
841 }
842 /* check for pending inserts here */
843 ret = 0;
844
845 error:
846 btrfs_free_path(path);
847 return ret;
848 }
849
850 static int btrfs_free_dev_extent(struct btrfs_trans_handle *trans,
851 struct btrfs_device *device,
852 u64 start)
853 {
854 int ret;
855 struct btrfs_path *path;
856 struct btrfs_root *root = device->dev_root;
857 struct btrfs_key key;
858 struct btrfs_key found_key;
859 struct extent_buffer *leaf = NULL;
860 struct btrfs_dev_extent *extent = NULL;
861
862 path = btrfs_alloc_path();
863 if (!path)
864 return -ENOMEM;
865
866 key.objectid = device->devid;
867 key.offset = start;
868 key.type = BTRFS_DEV_EXTENT_KEY;
869
870 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
871 if (ret > 0) {
872 ret = btrfs_previous_item(root, path, key.objectid,
873 BTRFS_DEV_EXTENT_KEY);
874 BUG_ON(ret);
875 leaf = path->nodes[0];
876 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
877 extent = btrfs_item_ptr(leaf, path->slots[0],
878 struct btrfs_dev_extent);
879 BUG_ON(found_key.offset > start || found_key.offset +
880 btrfs_dev_extent_length(leaf, extent) < start);
881 ret = 0;
882 } else if (ret == 0) {
883 leaf = path->nodes[0];
884 extent = btrfs_item_ptr(leaf, path->slots[0],
885 struct btrfs_dev_extent);
886 }
887 BUG_ON(ret);
888
889 if (device->bytes_used > 0)
890 device->bytes_used -= btrfs_dev_extent_length(leaf, extent);
891 ret = btrfs_del_item(trans, root, path);
892 BUG_ON(ret);
893
894 btrfs_free_path(path);
895 return ret;
896 }
897
898 int btrfs_alloc_dev_extent(struct btrfs_trans_handle *trans,
899 struct btrfs_device *device,
900 u64 chunk_tree, u64 chunk_objectid,
901 u64 chunk_offset, u64 start, u64 num_bytes)
902 {
903 int ret;
904 struct btrfs_path *path;
905 struct btrfs_root *root = device->dev_root;
906 struct btrfs_dev_extent *extent;
907 struct extent_buffer *leaf;
908 struct btrfs_key key;
909
910 WARN_ON(!device->in_fs_metadata);
911 path = btrfs_alloc_path();
912 if (!path)
913 return -ENOMEM;
914
915 key.objectid = device->devid;
916 key.offset = start;
917 key.type = BTRFS_DEV_EXTENT_KEY;
918 ret = btrfs_insert_empty_item(trans, root, path, &key,
919 sizeof(*extent));
920 BUG_ON(ret);
921
922 leaf = path->nodes[0];
923 extent = btrfs_item_ptr(leaf, path->slots[0],
924 struct btrfs_dev_extent);
925 btrfs_set_dev_extent_chunk_tree(leaf, extent, chunk_tree);
926 btrfs_set_dev_extent_chunk_objectid(leaf, extent, chunk_objectid);
927 btrfs_set_dev_extent_chunk_offset(leaf, extent, chunk_offset);
928
929 write_extent_buffer(leaf, root->fs_info->chunk_tree_uuid,
930 (unsigned long)btrfs_dev_extent_chunk_tree_uuid(extent),
931 BTRFS_UUID_SIZE);
932
933 btrfs_set_dev_extent_length(leaf, extent, num_bytes);
934 btrfs_mark_buffer_dirty(leaf);
935 btrfs_free_path(path);
936 return ret;
937 }
938
939 static noinline int find_next_chunk(struct btrfs_root *root,
940 u64 objectid, u64 *offset)
941 {
942 struct btrfs_path *path;
943 int ret;
944 struct btrfs_key key;
945 struct btrfs_chunk *chunk;
946 struct btrfs_key found_key;
947
948 path = btrfs_alloc_path();
949 BUG_ON(!path);
950
951 key.objectid = objectid;
952 key.offset = (u64)-1;
953 key.type = BTRFS_CHUNK_ITEM_KEY;
954
955 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
956 if (ret < 0)
957 goto error;
958
959 BUG_ON(ret == 0);
960
961 ret = btrfs_previous_item(root, path, 0, BTRFS_CHUNK_ITEM_KEY);
962 if (ret) {
963 *offset = 0;
964 } else {
965 btrfs_item_key_to_cpu(path->nodes[0], &found_key,
966 path->slots[0]);
967 if (found_key.objectid != objectid)
968 *offset = 0;
969 else {
970 chunk = btrfs_item_ptr(path->nodes[0], path->slots[0],
971 struct btrfs_chunk);
972 *offset = found_key.offset +
973 btrfs_chunk_length(path->nodes[0], chunk);
974 }
975 }
976 ret = 0;
977 error:
978 btrfs_free_path(path);
979 return ret;
980 }
981
982 static noinline int find_next_devid(struct btrfs_root *root, u64 *objectid)
983 {
984 int ret;
985 struct btrfs_key key;
986 struct btrfs_key found_key;
987 struct btrfs_path *path;
988
989 root = root->fs_info->chunk_root;
990
991 path = btrfs_alloc_path();
992 if (!path)
993 return -ENOMEM;
994
995 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
996 key.type = BTRFS_DEV_ITEM_KEY;
997 key.offset = (u64)-1;
998
999 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1000 if (ret < 0)
1001 goto error;
1002
1003 BUG_ON(ret == 0);
1004
1005 ret = btrfs_previous_item(root, path, BTRFS_DEV_ITEMS_OBJECTID,
1006 BTRFS_DEV_ITEM_KEY);
1007 if (ret) {
1008 *objectid = 1;
1009 } else {
1010 btrfs_item_key_to_cpu(path->nodes[0], &found_key,
1011 path->slots[0]);
1012 *objectid = found_key.offset + 1;
1013 }
1014 ret = 0;
1015 error:
1016 btrfs_free_path(path);
1017 return ret;
1018 }
1019
1020 /*
1021 * the device information is stored in the chunk root
1022 * the btrfs_device struct should be fully filled in
1023 */
1024 int btrfs_add_device(struct btrfs_trans_handle *trans,
1025 struct btrfs_root *root,
1026 struct btrfs_device *device)
1027 {
1028 int ret;
1029 struct btrfs_path *path;
1030 struct btrfs_dev_item *dev_item;
1031 struct extent_buffer *leaf;
1032 struct btrfs_key key;
1033 unsigned long ptr;
1034
1035 root = root->fs_info->chunk_root;
1036
1037 path = btrfs_alloc_path();
1038 if (!path)
1039 return -ENOMEM;
1040
1041 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
1042 key.type = BTRFS_DEV_ITEM_KEY;
1043 key.offset = device->devid;
1044
1045 ret = btrfs_insert_empty_item(trans, root, path, &key,
1046 sizeof(*dev_item));
1047 if (ret)
1048 goto out;
1049
1050 leaf = path->nodes[0];
1051 dev_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dev_item);
1052
1053 btrfs_set_device_id(leaf, dev_item, device->devid);
1054 btrfs_set_device_generation(leaf, dev_item, 0);
1055 btrfs_set_device_type(leaf, dev_item, device->type);
1056 btrfs_set_device_io_align(leaf, dev_item, device->io_align);
1057 btrfs_set_device_io_width(leaf, dev_item, device->io_width);
1058 btrfs_set_device_sector_size(leaf, dev_item, device->sector_size);
1059 btrfs_set_device_total_bytes(leaf, dev_item, device->total_bytes);
1060 btrfs_set_device_bytes_used(leaf, dev_item, device->bytes_used);
1061 btrfs_set_device_group(leaf, dev_item, 0);
1062 btrfs_set_device_seek_speed(leaf, dev_item, 0);
1063 btrfs_set_device_bandwidth(leaf, dev_item, 0);
1064 btrfs_set_device_start_offset(leaf, dev_item, 0);
1065
1066 ptr = (unsigned long)btrfs_device_uuid(dev_item);
1067 write_extent_buffer(leaf, device->uuid, ptr, BTRFS_UUID_SIZE);
1068 ptr = (unsigned long)btrfs_device_fsid(dev_item);
1069 write_extent_buffer(leaf, root->fs_info->fsid, ptr, BTRFS_UUID_SIZE);
1070 btrfs_mark_buffer_dirty(leaf);
1071
1072 ret = 0;
1073 out:
1074 btrfs_free_path(path);
1075 return ret;
1076 }
1077
1078 static int btrfs_rm_dev_item(struct btrfs_root *root,
1079 struct btrfs_device *device)
1080 {
1081 int ret;
1082 struct btrfs_path *path;
1083 struct btrfs_key key;
1084 struct btrfs_trans_handle *trans;
1085
1086 root = root->fs_info->chunk_root;
1087
1088 path = btrfs_alloc_path();
1089 if (!path)
1090 return -ENOMEM;
1091
1092 trans = btrfs_start_transaction(root, 1);
1093 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
1094 key.type = BTRFS_DEV_ITEM_KEY;
1095 key.offset = device->devid;
1096 lock_chunks(root);
1097
1098 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1099 if (ret < 0)
1100 goto out;
1101
1102 if (ret > 0) {
1103 ret = -ENOENT;
1104 goto out;
1105 }
1106
1107 ret = btrfs_del_item(trans, root, path);
1108 if (ret)
1109 goto out;
1110 out:
1111 btrfs_free_path(path);
1112 unlock_chunks(root);
1113 btrfs_commit_transaction(trans, root);
1114 return ret;
1115 }
1116
1117 int btrfs_rm_device(struct btrfs_root *root, char *device_path)
1118 {
1119 struct btrfs_device *device;
1120 struct btrfs_device *next_device;
1121 struct block_device *bdev;
1122 struct buffer_head *bh = NULL;
1123 struct btrfs_super_block *disk_super;
1124 u64 all_avail;
1125 u64 devid;
1126 u64 num_devices;
1127 u8 *dev_uuid;
1128 int ret = 0;
1129
1130 mutex_lock(&uuid_mutex);
1131 mutex_lock(&root->fs_info->volume_mutex);
1132
1133 all_avail = root->fs_info->avail_data_alloc_bits |
1134 root->fs_info->avail_system_alloc_bits |
1135 root->fs_info->avail_metadata_alloc_bits;
1136
1137 if ((all_avail & BTRFS_BLOCK_GROUP_RAID10) &&
1138 root->fs_info->fs_devices->num_devices <= 4) {
1139 printk(KERN_ERR "btrfs: unable to go below four devices "
1140 "on raid10\n");
1141 ret = -EINVAL;
1142 goto out;
1143 }
1144
1145 if ((all_avail & BTRFS_BLOCK_GROUP_RAID1) &&
1146 root->fs_info->fs_devices->num_devices <= 2) {
1147 printk(KERN_ERR "btrfs: unable to go below two "
1148 "devices on raid1\n");
1149 ret = -EINVAL;
1150 goto out;
1151 }
1152
1153 if (strcmp(device_path, "missing") == 0) {
1154 struct list_head *devices;
1155 struct btrfs_device *tmp;
1156
1157 device = NULL;
1158 devices = &root->fs_info->fs_devices->devices;
1159 mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
1160 list_for_each_entry(tmp, devices, dev_list) {
1161 if (tmp->in_fs_metadata && !tmp->bdev) {
1162 device = tmp;
1163 break;
1164 }
1165 }
1166 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
1167 bdev = NULL;
1168 bh = NULL;
1169 disk_super = NULL;
1170 if (!device) {
1171 printk(KERN_ERR "btrfs: no missing devices found to "
1172 "remove\n");
1173 goto out;
1174 }
1175 } else {
1176 bdev = open_bdev_exclusive(device_path, FMODE_READ,
1177 root->fs_info->bdev_holder);
1178 if (IS_ERR(bdev)) {
1179 ret = PTR_ERR(bdev);
1180 goto out;
1181 }
1182
1183 set_blocksize(bdev, 4096);
1184 bh = btrfs_read_dev_super(bdev);
1185 if (!bh) {
1186 ret = -EIO;
1187 goto error_close;
1188 }
1189 disk_super = (struct btrfs_super_block *)bh->b_data;
1190 devid = le64_to_cpu(disk_super->dev_item.devid);
1191 dev_uuid = disk_super->dev_item.uuid;
1192 device = btrfs_find_device(root, devid, dev_uuid,
1193 disk_super->fsid);
1194 if (!device) {
1195 ret = -ENOENT;
1196 goto error_brelse;
1197 }
1198 }
1199
1200 if (device->writeable && root->fs_info->fs_devices->rw_devices == 1) {
1201 printk(KERN_ERR "btrfs: unable to remove the only writeable "
1202 "device\n");
1203 ret = -EINVAL;
1204 goto error_brelse;
1205 }
1206
1207 if (device->writeable) {
1208 list_del_init(&device->dev_alloc_list);
1209 root->fs_info->fs_devices->rw_devices--;
1210 }
1211
1212 ret = btrfs_shrink_device(device, 0);
1213 if (ret)
1214 goto error_brelse;
1215
1216 ret = btrfs_rm_dev_item(root->fs_info->chunk_root, device);
1217 if (ret)
1218 goto error_brelse;
1219
1220 device->in_fs_metadata = 0;
1221
1222 /*
1223 * the device list mutex makes sure that we don't change
1224 * the device list while someone else is writing out all
1225 * the device supers.
1226 */
1227 mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
1228 list_del_init(&device->dev_list);
1229 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
1230
1231 device->fs_devices->num_devices--;
1232
1233 next_device = list_entry(root->fs_info->fs_devices->devices.next,
1234 struct btrfs_device, dev_list);
1235 if (device->bdev == root->fs_info->sb->s_bdev)
1236 root->fs_info->sb->s_bdev = next_device->bdev;
1237 if (device->bdev == root->fs_info->fs_devices->latest_bdev)
1238 root->fs_info->fs_devices->latest_bdev = next_device->bdev;
1239
1240 if (device->bdev) {
1241 close_bdev_exclusive(device->bdev, device->mode);
1242 device->bdev = NULL;
1243 device->fs_devices->open_devices--;
1244 }
1245
1246 num_devices = btrfs_super_num_devices(&root->fs_info->super_copy) - 1;
1247 btrfs_set_super_num_devices(&root->fs_info->super_copy, num_devices);
1248
1249 if (device->fs_devices->open_devices == 0) {
1250 struct btrfs_fs_devices *fs_devices;
1251 fs_devices = root->fs_info->fs_devices;
1252 while (fs_devices) {
1253 if (fs_devices->seed == device->fs_devices)
1254 break;
1255 fs_devices = fs_devices->seed;
1256 }
1257 fs_devices->seed = device->fs_devices->seed;
1258 device->fs_devices->seed = NULL;
1259 __btrfs_close_devices(device->fs_devices);
1260 free_fs_devices(device->fs_devices);
1261 }
1262
1263 /*
1264 * at this point, the device is zero sized. We want to
1265 * remove it from the devices list and zero out the old super
1266 */
1267 if (device->writeable) {
1268 /* make sure this device isn't detected as part of
1269 * the FS anymore
1270 */
1271 memset(&disk_super->magic, 0, sizeof(disk_super->magic));
1272 set_buffer_dirty(bh);
1273 sync_dirty_buffer(bh);
1274 }
1275
1276 kfree(device->name);
1277 kfree(device);
1278 ret = 0;
1279
1280 error_brelse:
1281 brelse(bh);
1282 error_close:
1283 if (bdev)
1284 close_bdev_exclusive(bdev, FMODE_READ);
1285 out:
1286 mutex_unlock(&root->fs_info->volume_mutex);
1287 mutex_unlock(&uuid_mutex);
1288 return ret;
1289 }
1290
1291 /*
1292 * does all the dirty work required for changing file system's UUID.
1293 */
1294 static int btrfs_prepare_sprout(struct btrfs_trans_handle *trans,
1295 struct btrfs_root *root)
1296 {
1297 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
1298 struct btrfs_fs_devices *old_devices;
1299 struct btrfs_fs_devices *seed_devices;
1300 struct btrfs_super_block *disk_super = &root->fs_info->super_copy;
1301 struct btrfs_device *device;
1302 u64 super_flags;
1303
1304 BUG_ON(!mutex_is_locked(&uuid_mutex));
1305 if (!fs_devices->seeding)
1306 return -EINVAL;
1307
1308 seed_devices = kzalloc(sizeof(*fs_devices), GFP_NOFS);
1309 if (!seed_devices)
1310 return -ENOMEM;
1311
1312 old_devices = clone_fs_devices(fs_devices);
1313 if (IS_ERR(old_devices)) {
1314 kfree(seed_devices);
1315 return PTR_ERR(old_devices);
1316 }
1317
1318 list_add(&old_devices->list, &fs_uuids);
1319
1320 memcpy(seed_devices, fs_devices, sizeof(*seed_devices));
1321 seed_devices->opened = 1;
1322 INIT_LIST_HEAD(&seed_devices->devices);
1323 INIT_LIST_HEAD(&seed_devices->alloc_list);
1324 mutex_init(&seed_devices->device_list_mutex);
1325 list_splice_init(&fs_devices->devices, &seed_devices->devices);
1326 list_splice_init(&fs_devices->alloc_list, &seed_devices->alloc_list);
1327 list_for_each_entry(device, &seed_devices->devices, dev_list) {
1328 device->fs_devices = seed_devices;
1329 }
1330
1331 fs_devices->seeding = 0;
1332 fs_devices->num_devices = 0;
1333 fs_devices->open_devices = 0;
1334 fs_devices->seed = seed_devices;
1335
1336 generate_random_uuid(fs_devices->fsid);
1337 memcpy(root->fs_info->fsid, fs_devices->fsid, BTRFS_FSID_SIZE);
1338 memcpy(disk_super->fsid, fs_devices->fsid, BTRFS_FSID_SIZE);
1339 super_flags = btrfs_super_flags(disk_super) &
1340 ~BTRFS_SUPER_FLAG_SEEDING;
1341 btrfs_set_super_flags(disk_super, super_flags);
1342
1343 return 0;
1344 }
1345
1346 /*
1347 * strore the expected generation for seed devices in device items.
1348 */
1349 static int btrfs_finish_sprout(struct btrfs_trans_handle *trans,
1350 struct btrfs_root *root)
1351 {
1352 struct btrfs_path *path;
1353 struct extent_buffer *leaf;
1354 struct btrfs_dev_item *dev_item;
1355 struct btrfs_device *device;
1356 struct btrfs_key key;
1357 u8 fs_uuid[BTRFS_UUID_SIZE];
1358 u8 dev_uuid[BTRFS_UUID_SIZE];
1359 u64 devid;
1360 int ret;
1361
1362 path = btrfs_alloc_path();
1363 if (!path)
1364 return -ENOMEM;
1365
1366 root = root->fs_info->chunk_root;
1367 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
1368 key.offset = 0;
1369 key.type = BTRFS_DEV_ITEM_KEY;
1370
1371 while (1) {
1372 ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
1373 if (ret < 0)
1374 goto error;
1375
1376 leaf = path->nodes[0];
1377 next_slot:
1378 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
1379 ret = btrfs_next_leaf(root, path);
1380 if (ret > 0)
1381 break;
1382 if (ret < 0)
1383 goto error;
1384 leaf = path->nodes[0];
1385 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
1386 btrfs_release_path(root, path);
1387 continue;
1388 }
1389
1390 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
1391 if (key.objectid != BTRFS_DEV_ITEMS_OBJECTID ||
1392 key.type != BTRFS_DEV_ITEM_KEY)
1393 break;
1394
1395 dev_item = btrfs_item_ptr(leaf, path->slots[0],
1396 struct btrfs_dev_item);
1397 devid = btrfs_device_id(leaf, dev_item);
1398 read_extent_buffer(leaf, dev_uuid,
1399 (unsigned long)btrfs_device_uuid(dev_item),
1400 BTRFS_UUID_SIZE);
1401 read_extent_buffer(leaf, fs_uuid,
1402 (unsigned long)btrfs_device_fsid(dev_item),
1403 BTRFS_UUID_SIZE);
1404 device = btrfs_find_device(root, devid, dev_uuid, fs_uuid);
1405 BUG_ON(!device);
1406
1407 if (device->fs_devices->seeding) {
1408 btrfs_set_device_generation(leaf, dev_item,
1409 device->generation);
1410 btrfs_mark_buffer_dirty(leaf);
1411 }
1412
1413 path->slots[0]++;
1414 goto next_slot;
1415 }
1416 ret = 0;
1417 error:
1418 btrfs_free_path(path);
1419 return ret;
1420 }
1421
1422 int btrfs_init_new_device(struct btrfs_root *root, char *device_path)
1423 {
1424 struct btrfs_trans_handle *trans;
1425 struct btrfs_device *device;
1426 struct block_device *bdev;
1427 struct list_head *devices;
1428 struct super_block *sb = root->fs_info->sb;
1429 u64 total_bytes;
1430 int seeding_dev = 0;
1431 int ret = 0;
1432
1433 if ((sb->s_flags & MS_RDONLY) && !root->fs_info->fs_devices->seeding)
1434 return -EINVAL;
1435
1436 bdev = open_bdev_exclusive(device_path, 0, root->fs_info->bdev_holder);
1437 if (IS_ERR(bdev))
1438 return PTR_ERR(bdev);
1439
1440 if (root->fs_info->fs_devices->seeding) {
1441 seeding_dev = 1;
1442 down_write(&sb->s_umount);
1443 mutex_lock(&uuid_mutex);
1444 }
1445
1446 filemap_write_and_wait(bdev->bd_inode->i_mapping);
1447 mutex_lock(&root->fs_info->volume_mutex);
1448
1449 devices = &root->fs_info->fs_devices->devices;
1450 /*
1451 * we have the volume lock, so we don't need the extra
1452 * device list mutex while reading the list here.
1453 */
1454 list_for_each_entry(device, devices, dev_list) {
1455 if (device->bdev == bdev) {
1456 ret = -EEXIST;
1457 goto error;
1458 }
1459 }
1460
1461 device = kzalloc(sizeof(*device), GFP_NOFS);
1462 if (!device) {
1463 /* we can safely leave the fs_devices entry around */
1464 ret = -ENOMEM;
1465 goto error;
1466 }
1467
1468 device->name = kstrdup(device_path, GFP_NOFS);
1469 if (!device->name) {
1470 kfree(device);
1471 ret = -ENOMEM;
1472 goto error;
1473 }
1474
1475 ret = find_next_devid(root, &device->devid);
1476 if (ret) {
1477 kfree(device);
1478 goto error;
1479 }
1480
1481 trans = btrfs_start_transaction(root, 1);
1482 lock_chunks(root);
1483
1484 device->barriers = 1;
1485 device->writeable = 1;
1486 device->work.func = pending_bios_fn;
1487 generate_random_uuid(device->uuid);
1488 spin_lock_init(&device->io_lock);
1489 device->generation = trans->transid;
1490 device->io_width = root->sectorsize;
1491 device->io_align = root->sectorsize;
1492 device->sector_size = root->sectorsize;
1493 device->total_bytes = i_size_read(bdev->bd_inode);
1494 device->disk_total_bytes = device->total_bytes;
1495 device->dev_root = root->fs_info->dev_root;
1496 device->bdev = bdev;
1497 device->in_fs_metadata = 1;
1498 device->mode = 0;
1499 set_blocksize(device->bdev, 4096);
1500
1501 if (seeding_dev) {
1502 sb->s_flags &= ~MS_RDONLY;
1503 ret = btrfs_prepare_sprout(trans, root);
1504 BUG_ON(ret);
1505 }
1506
1507 device->fs_devices = root->fs_info->fs_devices;
1508
1509 /*
1510 * we don't want write_supers to jump in here with our device
1511 * half setup
1512 */
1513 mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
1514 list_add(&device->dev_list, &root->fs_info->fs_devices->devices);
1515 list_add(&device->dev_alloc_list,
1516 &root->fs_info->fs_devices->alloc_list);
1517 root->fs_info->fs_devices->num_devices++;
1518 root->fs_info->fs_devices->open_devices++;
1519 root->fs_info->fs_devices->rw_devices++;
1520 root->fs_info->fs_devices->total_rw_bytes += device->total_bytes;
1521
1522 if (!blk_queue_nonrot(bdev_get_queue(bdev)))
1523 root->fs_info->fs_devices->rotating = 1;
1524
1525 total_bytes = btrfs_super_total_bytes(&root->fs_info->super_copy);
1526 btrfs_set_super_total_bytes(&root->fs_info->super_copy,
1527 total_bytes + device->total_bytes);
1528
1529 total_bytes = btrfs_super_num_devices(&root->fs_info->super_copy);
1530 btrfs_set_super_num_devices(&root->fs_info->super_copy,
1531 total_bytes + 1);
1532 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
1533
1534 if (seeding_dev) {
1535 ret = init_first_rw_device(trans, root, device);
1536 BUG_ON(ret);
1537 ret = btrfs_finish_sprout(trans, root);
1538 BUG_ON(ret);
1539 } else {
1540 ret = btrfs_add_device(trans, root, device);
1541 }
1542
1543 /*
1544 * we've got more storage, clear any full flags on the space
1545 * infos
1546 */
1547 btrfs_clear_space_info_full(root->fs_info);
1548
1549 unlock_chunks(root);
1550 btrfs_commit_transaction(trans, root);
1551
1552 if (seeding_dev) {
1553 mutex_unlock(&uuid_mutex);
1554 up_write(&sb->s_umount);
1555
1556 ret = btrfs_relocate_sys_chunks(root);
1557 BUG_ON(ret);
1558 }
1559 out:
1560 mutex_unlock(&root->fs_info->volume_mutex);
1561 return ret;
1562 error:
1563 close_bdev_exclusive(bdev, 0);
1564 if (seeding_dev) {
1565 mutex_unlock(&uuid_mutex);
1566 up_write(&sb->s_umount);
1567 }
1568 goto out;
1569 }
1570
1571 static noinline int btrfs_update_device(struct btrfs_trans_handle *trans,
1572 struct btrfs_device *device)
1573 {
1574 int ret;
1575 struct btrfs_path *path;
1576 struct btrfs_root *root;
1577 struct btrfs_dev_item *dev_item;
1578 struct extent_buffer *leaf;
1579 struct btrfs_key key;
1580
1581 root = device->dev_root->fs_info->chunk_root;
1582
1583 path = btrfs_alloc_path();
1584 if (!path)
1585 return -ENOMEM;
1586
1587 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
1588 key.type = BTRFS_DEV_ITEM_KEY;
1589 key.offset = device->devid;
1590
1591 ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
1592 if (ret < 0)
1593 goto out;
1594
1595 if (ret > 0) {
1596 ret = -ENOENT;
1597 goto out;
1598 }
1599
1600 leaf = path->nodes[0];
1601 dev_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dev_item);
1602
1603 btrfs_set_device_id(leaf, dev_item, device->devid);
1604 btrfs_set_device_type(leaf, dev_item, device->type);
1605 btrfs_set_device_io_align(leaf, dev_item, device->io_align);
1606 btrfs_set_device_io_width(leaf, dev_item, device->io_width);
1607 btrfs_set_device_sector_size(leaf, dev_item, device->sector_size);
1608 btrfs_set_device_total_bytes(leaf, dev_item, device->disk_total_bytes);
1609 btrfs_set_device_bytes_used(leaf, dev_item, device->bytes_used);
1610 btrfs_mark_buffer_dirty(leaf);
1611
1612 out:
1613 btrfs_free_path(path);
1614 return ret;
1615 }
1616
1617 static int __btrfs_grow_device(struct btrfs_trans_handle *trans,
1618 struct btrfs_device *device, u64 new_size)
1619 {
1620 struct btrfs_super_block *super_copy =
1621 &device->dev_root->fs_info->super_copy;
1622 u64 old_total = btrfs_super_total_bytes(super_copy);
1623 u64 diff = new_size - device->total_bytes;
1624
1625 if (!device->writeable)
1626 return -EACCES;
1627 if (new_size <= device->total_bytes)
1628 return -EINVAL;
1629
1630 btrfs_set_super_total_bytes(super_copy, old_total + diff);
1631 device->fs_devices->total_rw_bytes += diff;
1632
1633 device->total_bytes = new_size;
1634 device->disk_total_bytes = new_size;
1635 btrfs_clear_space_info_full(device->dev_root->fs_info);
1636
1637 return btrfs_update_device(trans, device);
1638 }
1639
1640 int btrfs_grow_device(struct btrfs_trans_handle *trans,
1641 struct btrfs_device *device, u64 new_size)
1642 {
1643 int ret;
1644 lock_chunks(device->dev_root);
1645 ret = __btrfs_grow_device(trans, device, new_size);
1646 unlock_chunks(device->dev_root);
1647 return ret;
1648 }
1649
1650 static int btrfs_free_chunk(struct btrfs_trans_handle *trans,
1651 struct btrfs_root *root,
1652 u64 chunk_tree, u64 chunk_objectid,
1653 u64 chunk_offset)
1654 {
1655 int ret;
1656 struct btrfs_path *path;
1657 struct btrfs_key key;
1658
1659 root = root->fs_info->chunk_root;
1660 path = btrfs_alloc_path();
1661 if (!path)
1662 return -ENOMEM;
1663
1664 key.objectid = chunk_objectid;
1665 key.offset = chunk_offset;
1666 key.type = BTRFS_CHUNK_ITEM_KEY;
1667
1668 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1669 BUG_ON(ret);
1670
1671 ret = btrfs_del_item(trans, root, path);
1672 BUG_ON(ret);
1673
1674 btrfs_free_path(path);
1675 return 0;
1676 }
1677
1678 static int btrfs_del_sys_chunk(struct btrfs_root *root, u64 chunk_objectid, u64
1679 chunk_offset)
1680 {
1681 struct btrfs_super_block *super_copy = &root->fs_info->super_copy;
1682 struct btrfs_disk_key *disk_key;
1683 struct btrfs_chunk *chunk;
1684 u8 *ptr;
1685 int ret = 0;
1686 u32 num_stripes;
1687 u32 array_size;
1688 u32 len = 0;
1689 u32 cur;
1690 struct btrfs_key key;
1691
1692 array_size = btrfs_super_sys_array_size(super_copy);
1693
1694 ptr = super_copy->sys_chunk_array;
1695 cur = 0;
1696
1697 while (cur < array_size) {
1698 disk_key = (struct btrfs_disk_key *)ptr;
1699 btrfs_disk_key_to_cpu(&key, disk_key);
1700
1701 len = sizeof(*disk_key);
1702
1703 if (key.type == BTRFS_CHUNK_ITEM_KEY) {
1704 chunk = (struct btrfs_chunk *)(ptr + len);
1705 num_stripes = btrfs_stack_chunk_num_stripes(chunk);
1706 len += btrfs_chunk_item_size(num_stripes);
1707 } else {
1708 ret = -EIO;
1709 break;
1710 }
1711 if (key.objectid == chunk_objectid &&
1712 key.offset == chunk_offset) {
1713 memmove(ptr, ptr + len, array_size - (cur + len));
1714 array_size -= len;
1715 btrfs_set_super_sys_array_size(super_copy, array_size);
1716 } else {
1717 ptr += len;
1718 cur += len;
1719 }
1720 }
1721 return ret;
1722 }
1723
1724 static int btrfs_relocate_chunk(struct btrfs_root *root,
1725 u64 chunk_tree, u64 chunk_objectid,
1726 u64 chunk_offset)
1727 {
1728 struct extent_map_tree *em_tree;
1729 struct btrfs_root *extent_root;
1730 struct btrfs_trans_handle *trans;
1731 struct extent_map *em;
1732 struct map_lookup *map;
1733 int ret;
1734 int i;
1735
1736 root = root->fs_info->chunk_root;
1737 extent_root = root->fs_info->extent_root;
1738 em_tree = &root->fs_info->mapping_tree.map_tree;
1739
1740 ret = btrfs_can_relocate(extent_root, chunk_offset);
1741 if (ret)
1742 return -ENOSPC;
1743
1744 /* step one, relocate all the extents inside this chunk */
1745 ret = btrfs_relocate_block_group(extent_root, chunk_offset);
1746 BUG_ON(ret);
1747
1748 trans = btrfs_start_transaction(root, 1);
1749 BUG_ON(!trans);
1750
1751 lock_chunks(root);
1752
1753 /*
1754 * step two, delete the device extents and the
1755 * chunk tree entries
1756 */
1757 read_lock(&em_tree->lock);
1758 em = lookup_extent_mapping(em_tree, chunk_offset, 1);
1759 read_unlock(&em_tree->lock);
1760
1761 BUG_ON(em->start > chunk_offset ||
1762 em->start + em->len < chunk_offset);
1763 map = (struct map_lookup *)em->bdev;
1764
1765 for (i = 0; i < map->num_stripes; i++) {
1766 ret = btrfs_free_dev_extent(trans, map->stripes[i].dev,
1767 map->stripes[i].physical);
1768 BUG_ON(ret);
1769
1770 if (map->stripes[i].dev) {
1771 ret = btrfs_update_device(trans, map->stripes[i].dev);
1772 BUG_ON(ret);
1773 }
1774 }
1775 ret = btrfs_free_chunk(trans, root, chunk_tree, chunk_objectid,
1776 chunk_offset);
1777
1778 BUG_ON(ret);
1779
1780 if (map->type & BTRFS_BLOCK_GROUP_SYSTEM) {
1781 ret = btrfs_del_sys_chunk(root, chunk_objectid, chunk_offset);
1782 BUG_ON(ret);
1783 }
1784
1785 ret = btrfs_remove_block_group(trans, extent_root, chunk_offset);
1786 BUG_ON(ret);
1787
1788 write_lock(&em_tree->lock);
1789 remove_extent_mapping(em_tree, em);
1790 write_unlock(&em_tree->lock);
1791
1792 kfree(map);
1793 em->bdev = NULL;
1794
1795 /* once for the tree */
1796 free_extent_map(em);
1797 /* once for us */
1798 free_extent_map(em);
1799
1800 unlock_chunks(root);
1801 btrfs_end_transaction(trans, root);
1802 return 0;
1803 }
1804
1805 static int btrfs_relocate_sys_chunks(struct btrfs_root *root)
1806 {
1807 struct btrfs_root *chunk_root = root->fs_info->chunk_root;
1808 struct btrfs_path *path;
1809 struct extent_buffer *leaf;
1810 struct btrfs_chunk *chunk;
1811 struct btrfs_key key;
1812 struct btrfs_key found_key;
1813 u64 chunk_tree = chunk_root->root_key.objectid;
1814 u64 chunk_type;
1815 bool retried = false;
1816 int failed = 0;
1817 int ret;
1818
1819 path = btrfs_alloc_path();
1820 if (!path)
1821 return -ENOMEM;
1822
1823 again:
1824 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
1825 key.offset = (u64)-1;
1826 key.type = BTRFS_CHUNK_ITEM_KEY;
1827
1828 while (1) {
1829 ret = btrfs_search_slot(NULL, chunk_root, &key, path, 0, 0);
1830 if (ret < 0)
1831 goto error;
1832 BUG_ON(ret == 0);
1833
1834 ret = btrfs_previous_item(chunk_root, path, key.objectid,
1835 key.type);
1836 if (ret < 0)
1837 goto error;
1838 if (ret > 0)
1839 break;
1840
1841 leaf = path->nodes[0];
1842 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
1843
1844 chunk = btrfs_item_ptr(leaf, path->slots[0],
1845 struct btrfs_chunk);
1846 chunk_type = btrfs_chunk_type(leaf, chunk);
1847 btrfs_release_path(chunk_root, path);
1848
1849 if (chunk_type & BTRFS_BLOCK_GROUP_SYSTEM) {
1850 ret = btrfs_relocate_chunk(chunk_root, chunk_tree,
1851 found_key.objectid,
1852 found_key.offset);
1853 if (ret == -ENOSPC)
1854 failed++;
1855 else if (ret)
1856 BUG();
1857 }
1858
1859 if (found_key.offset == 0)
1860 break;
1861 key.offset = found_key.offset - 1;
1862 }
1863 ret = 0;
1864 if (failed && !retried) {
1865 failed = 0;
1866 retried = true;
1867 goto again;
1868 } else if (failed && retried) {
1869 WARN_ON(1);
1870 ret = -ENOSPC;
1871 }
1872 error:
1873 btrfs_free_path(path);
1874 return ret;
1875 }
1876
1877 static u64 div_factor(u64 num, int factor)
1878 {
1879 if (factor == 10)
1880 return num;
1881 num *= factor;
1882 do_div(num, 10);
1883 return num;
1884 }
1885
1886 int btrfs_balance(struct btrfs_root *dev_root)
1887 {
1888 int ret;
1889 struct list_head *devices = &dev_root->fs_info->fs_devices->devices;
1890 struct btrfs_device *device;
1891 u64 old_size;
1892 u64 size_to_free;
1893 struct btrfs_path *path;
1894 struct btrfs_key key;
1895 struct btrfs_chunk *chunk;
1896 struct btrfs_root *chunk_root = dev_root->fs_info->chunk_root;
1897 struct btrfs_trans_handle *trans;
1898 struct btrfs_key found_key;
1899
1900 if (dev_root->fs_info->sb->s_flags & MS_RDONLY)
1901 return -EROFS;
1902
1903 mutex_lock(&dev_root->fs_info->volume_mutex);
1904 dev_root = dev_root->fs_info->dev_root;
1905
1906 /* step one make some room on all the devices */
1907 list_for_each_entry(device, devices, dev_list) {
1908 old_size = device->total_bytes;
1909 size_to_free = div_factor(old_size, 1);
1910 size_to_free = min(size_to_free, (u64)1 * 1024 * 1024);
1911 if (!device->writeable ||
1912 device->total_bytes - device->bytes_used > size_to_free)
1913 continue;
1914
1915 ret = btrfs_shrink_device(device, old_size - size_to_free);
1916 if (ret == -ENOSPC)
1917 break;
1918 BUG_ON(ret);
1919
1920 trans = btrfs_start_transaction(dev_root, 1);
1921 BUG_ON(!trans);
1922
1923 ret = btrfs_grow_device(trans, device, old_size);
1924 BUG_ON(ret);
1925
1926 btrfs_end_transaction(trans, dev_root);
1927 }
1928
1929 /* step two, relocate all the chunks */
1930 path = btrfs_alloc_path();
1931 BUG_ON(!path);
1932
1933 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
1934 key.offset = (u64)-1;
1935 key.type = BTRFS_CHUNK_ITEM_KEY;
1936
1937 while (1) {
1938 ret = btrfs_search_slot(NULL, chunk_root, &key, path, 0, 0);
1939 if (ret < 0)
1940 goto error;
1941
1942 /*
1943 * this shouldn't happen, it means the last relocate
1944 * failed
1945 */
1946 if (ret == 0)
1947 break;
1948
1949 ret = btrfs_previous_item(chunk_root, path, 0,
1950 BTRFS_CHUNK_ITEM_KEY);
1951 if (ret)
1952 break;
1953
1954 btrfs_item_key_to_cpu(path->nodes[0], &found_key,
1955 path->slots[0]);
1956 if (found_key.objectid != key.objectid)
1957 break;
1958
1959 chunk = btrfs_item_ptr(path->nodes[0],
1960 path->slots[0],
1961 struct btrfs_chunk);
1962 /* chunk zero is special */
1963 if (found_key.offset == 0)
1964 break;
1965
1966 btrfs_release_path(chunk_root, path);
1967 ret = btrfs_relocate_chunk(chunk_root,
1968 chunk_root->root_key.objectid,
1969 found_key.objectid,
1970 found_key.offset);
1971 BUG_ON(ret && ret != -ENOSPC);
1972 key.offset = found_key.offset - 1;
1973 }
1974 ret = 0;
1975 error:
1976 btrfs_free_path(path);
1977 mutex_unlock(&dev_root->fs_info->volume_mutex);
1978 return ret;
1979 }
1980
1981 /*
1982 * shrinking a device means finding all of the device extents past
1983 * the new size, and then following the back refs to the chunks.
1984 * The chunk relocation code actually frees the device extent
1985 */
1986 int btrfs_shrink_device(struct btrfs_device *device, u64 new_size)
1987 {
1988 struct btrfs_trans_handle *trans;
1989 struct btrfs_root *root = device->dev_root;
1990 struct btrfs_dev_extent *dev_extent = NULL;
1991 struct btrfs_path *path;
1992 u64 length;
1993 u64 chunk_tree;
1994 u64 chunk_objectid;
1995 u64 chunk_offset;
1996 int ret;
1997 int slot;
1998 int failed = 0;
1999 bool retried = false;
2000 struct extent_buffer *l;
2001 struct btrfs_key key;
2002 struct btrfs_super_block *super_copy = &root->fs_info->super_copy;
2003 u64 old_total = btrfs_super_total_bytes(super_copy);
2004 u64 old_size = device->total_bytes;
2005 u64 diff = device->total_bytes - new_size;
2006
2007 if (new_size >= device->total_bytes)
2008 return -EINVAL;
2009
2010 path = btrfs_alloc_path();
2011 if (!path)
2012 return -ENOMEM;
2013
2014 path->reada = 2;
2015
2016 lock_chunks(root);
2017
2018 device->total_bytes = new_size;
2019 if (device->writeable)
2020 device->fs_devices->total_rw_bytes -= diff;
2021 unlock_chunks(root);
2022
2023 again:
2024 key.objectid = device->devid;
2025 key.offset = (u64)-1;
2026 key.type = BTRFS_DEV_EXTENT_KEY;
2027
2028 while (1) {
2029 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2030 if (ret < 0)
2031 goto done;
2032
2033 ret = btrfs_previous_item(root, path, 0, key.type);
2034 if (ret < 0)
2035 goto done;
2036 if (ret) {
2037 ret = 0;
2038 btrfs_release_path(root, path);
2039 break;
2040 }
2041
2042 l = path->nodes[0];
2043 slot = path->slots[0];
2044 btrfs_item_key_to_cpu(l, &key, path->slots[0]);
2045
2046 if (key.objectid != device->devid) {
2047 btrfs_release_path(root, path);
2048 break;
2049 }
2050
2051 dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent);
2052 length = btrfs_dev_extent_length(l, dev_extent);
2053
2054 if (key.offset + length <= new_size) {
2055 btrfs_release_path(root, path);
2056 break;
2057 }
2058
2059 chunk_tree = btrfs_dev_extent_chunk_tree(l, dev_extent);
2060 chunk_objectid = btrfs_dev_extent_chunk_objectid(l, dev_extent);
2061 chunk_offset = btrfs_dev_extent_chunk_offset(l, dev_extent);
2062 btrfs_release_path(root, path);
2063
2064 ret = btrfs_relocate_chunk(root, chunk_tree, chunk_objectid,
2065 chunk_offset);
2066 if (ret && ret != -ENOSPC)
2067 goto done;
2068 if (ret == -ENOSPC)
2069 failed++;
2070 key.offset -= 1;
2071 }
2072
2073 if (failed && !retried) {
2074 failed = 0;
2075 retried = true;
2076 goto again;
2077 } else if (failed && retried) {
2078 ret = -ENOSPC;
2079 lock_chunks(root);
2080
2081 device->total_bytes = old_size;
2082 if (device->writeable)
2083 device->fs_devices->total_rw_bytes += diff;
2084 unlock_chunks(root);
2085 goto done;
2086 }
2087
2088 /* Shrinking succeeded, else we would be at "done". */
2089 trans = btrfs_start_transaction(root, 1);
2090 if (!trans) {
2091 ret = -ENOMEM;
2092 goto done;
2093 }
2094 lock_chunks(root);
2095
2096 device->disk_total_bytes = new_size;
2097 /* Now btrfs_update_device() will change the on-disk size. */
2098 ret = btrfs_update_device(trans, device);
2099 if (ret) {
2100 unlock_chunks(root);
2101 btrfs_end_transaction(trans, root);
2102 goto done;
2103 }
2104 WARN_ON(diff > old_total);
2105 btrfs_set_super_total_bytes(super_copy, old_total - diff);
2106 unlock_chunks(root);
2107 btrfs_end_transaction(trans, root);
2108 done:
2109 btrfs_free_path(path);
2110 return ret;
2111 }
2112
2113 static int btrfs_add_system_chunk(struct btrfs_trans_handle *trans,
2114 struct btrfs_root *root,
2115 struct btrfs_key *key,
2116 struct btrfs_chunk *chunk, int item_size)
2117 {
2118 struct btrfs_super_block *super_copy = &root->fs_info->super_copy;
2119 struct btrfs_disk_key disk_key;
2120 u32 array_size;
2121 u8 *ptr;
2122
2123 array_size = btrfs_super_sys_array_size(super_copy);
2124 if (array_size + item_size > BTRFS_SYSTEM_CHUNK_ARRAY_SIZE)
2125 return -EFBIG;
2126
2127 ptr = super_copy->sys_chunk_array + array_size;
2128 btrfs_cpu_key_to_disk(&disk_key, key);
2129 memcpy(ptr, &disk_key, sizeof(disk_key));
2130 ptr += sizeof(disk_key);
2131 memcpy(ptr, chunk, item_size);
2132 item_size += sizeof(disk_key);
2133 btrfs_set_super_sys_array_size(super_copy, array_size + item_size);
2134 return 0;
2135 }
2136
2137 static noinline u64 chunk_bytes_by_type(u64 type, u64 calc_size,
2138 int num_stripes, int sub_stripes)
2139 {
2140 if (type & (BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_DUP))
2141 return calc_size;
2142 else if (type & BTRFS_BLOCK_GROUP_RAID10)
2143 return calc_size * (num_stripes / sub_stripes);
2144 else
2145 return calc_size * num_stripes;
2146 }
2147
2148 static int __btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
2149 struct btrfs_root *extent_root,
2150 struct map_lookup **map_ret,
2151 u64 *num_bytes, u64 *stripe_size,
2152 u64 start, u64 type)
2153 {
2154 struct btrfs_fs_info *info = extent_root->fs_info;
2155 struct btrfs_device *device = NULL;
2156 struct btrfs_fs_devices *fs_devices = info->fs_devices;
2157 struct list_head *cur;
2158 struct map_lookup *map = NULL;
2159 struct extent_map_tree *em_tree;
2160 struct extent_map *em;
2161 struct list_head private_devs;
2162 int min_stripe_size = 1 * 1024 * 1024;
2163 u64 calc_size = 1024 * 1024 * 1024;
2164 u64 max_chunk_size = calc_size;
2165 u64 min_free;
2166 u64 avail;
2167 u64 max_avail = 0;
2168 u64 dev_offset;
2169 int num_stripes = 1;
2170 int min_stripes = 1;
2171 int sub_stripes = 0;
2172 int looped = 0;
2173 int ret;
2174 int index;
2175 int stripe_len = 64 * 1024;
2176
2177 if ((type & BTRFS_BLOCK_GROUP_RAID1) &&
2178 (type & BTRFS_BLOCK_GROUP_DUP)) {
2179 WARN_ON(1);
2180 type &= ~BTRFS_BLOCK_GROUP_DUP;
2181 }
2182 if (list_empty(&fs_devices->alloc_list))
2183 return -ENOSPC;
2184
2185 if (type & (BTRFS_BLOCK_GROUP_RAID0)) {
2186 num_stripes = fs_devices->rw_devices;
2187 min_stripes = 2;
2188 }
2189 if (type & (BTRFS_BLOCK_GROUP_DUP)) {
2190 num_stripes = 2;
2191 min_stripes = 2;
2192 }
2193 if (type & (BTRFS_BLOCK_GROUP_RAID1)) {
2194 num_stripes = min_t(u64, 2, fs_devices->rw_devices);
2195 if (num_stripes < 2)
2196 return -ENOSPC;
2197 min_stripes = 2;
2198 }
2199 if (type & (BTRFS_BLOCK_GROUP_RAID10)) {
2200 num_stripes = fs_devices->rw_devices;
2201 if (num_stripes < 4)
2202 return -ENOSPC;
2203 num_stripes &= ~(u32)1;
2204 sub_stripes = 2;
2205 min_stripes = 4;
2206 }
2207
2208 if (type & BTRFS_BLOCK_GROUP_DATA) {
2209 max_chunk_size = 10 * calc_size;
2210 min_stripe_size = 64 * 1024 * 1024;
2211 } else if (type & BTRFS_BLOCK_GROUP_METADATA) {
2212 max_chunk_size = 256 * 1024 * 1024;
2213 min_stripe_size = 32 * 1024 * 1024;
2214 } else if (type & BTRFS_BLOCK_GROUP_SYSTEM) {
2215 calc_size = 8 * 1024 * 1024;
2216 max_chunk_size = calc_size * 2;
2217 min_stripe_size = 1 * 1024 * 1024;
2218 }
2219
2220 /* we don't want a chunk larger than 10% of writeable space */
2221 max_chunk_size = min(div_factor(fs_devices->total_rw_bytes, 1),
2222 max_chunk_size);
2223
2224 again:
2225 max_avail = 0;
2226 if (!map || map->num_stripes != num_stripes) {
2227 kfree(map);
2228 map = kmalloc(map_lookup_size(num_stripes), GFP_NOFS);
2229 if (!map)
2230 return -ENOMEM;
2231 map->num_stripes = num_stripes;
2232 }
2233
2234 if (calc_size * num_stripes > max_chunk_size) {
2235 calc_size = max_chunk_size;
2236 do_div(calc_size, num_stripes);
2237 do_div(calc_size, stripe_len);
2238 calc_size *= stripe_len;
2239 }
2240 /* we don't want tiny stripes */
2241 calc_size = max_t(u64, min_stripe_size, calc_size);
2242
2243 do_div(calc_size, stripe_len);
2244 calc_size *= stripe_len;
2245
2246 cur = fs_devices->alloc_list.next;
2247 index = 0;
2248
2249 if (type & BTRFS_BLOCK_GROUP_DUP)
2250 min_free = calc_size * 2;
2251 else
2252 min_free = calc_size;
2253
2254 /*
2255 * we add 1MB because we never use the first 1MB of the device, unless
2256 * we've looped, then we are likely allocating the maximum amount of
2257 * space left already
2258 */
2259 if (!looped)
2260 min_free += 1024 * 1024;
2261
2262 INIT_LIST_HEAD(&private_devs);
2263 while (index < num_stripes) {
2264 device = list_entry(cur, struct btrfs_device, dev_alloc_list);
2265 BUG_ON(!device->writeable);
2266 if (device->total_bytes > device->bytes_used)
2267 avail = device->total_bytes - device->bytes_used;
2268 else
2269 avail = 0;
2270 cur = cur->next;
2271
2272 if (device->in_fs_metadata && avail >= min_free) {
2273 ret = find_free_dev_extent(trans, device,
2274 min_free, &dev_offset,
2275 &max_avail);
2276 if (ret == 0) {
2277 list_move_tail(&device->dev_alloc_list,
2278 &private_devs);
2279 map->stripes[index].dev = device;
2280 map->stripes[index].physical = dev_offset;
2281 index++;
2282 if (type & BTRFS_BLOCK_GROUP_DUP) {
2283 map->stripes[index].dev = device;
2284 map->stripes[index].physical =
2285 dev_offset + calc_size;
2286 index++;
2287 }
2288 }
2289 } else if (device->in_fs_metadata && avail > max_avail)
2290 max_avail = avail;
2291 if (cur == &fs_devices->alloc_list)
2292 break;
2293 }
2294 list_splice(&private_devs, &fs_devices->alloc_list);
2295 if (index < num_stripes) {
2296 if (index >= min_stripes) {
2297 num_stripes = index;
2298 if (type & (BTRFS_BLOCK_GROUP_RAID10)) {
2299 num_stripes /= sub_stripes;
2300 num_stripes *= sub_stripes;
2301 }
2302 looped = 1;
2303 goto again;
2304 }
2305 if (!looped && max_avail > 0) {
2306 looped = 1;
2307 calc_size = max_avail;
2308 goto again;
2309 }
2310 kfree(map);
2311 return -ENOSPC;
2312 }
2313 map->sector_size = extent_root->sectorsize;
2314 map->stripe_len = stripe_len;
2315 map->io_align = stripe_len;
2316 map->io_width = stripe_len;
2317 map->type = type;
2318 map->num_stripes = num_stripes;
2319 map->sub_stripes = sub_stripes;
2320
2321 *map_ret = map;
2322 *stripe_size = calc_size;
2323 *num_bytes = chunk_bytes_by_type(type, calc_size,
2324 num_stripes, sub_stripes);
2325
2326 em = alloc_extent_map(GFP_NOFS);
2327 if (!em) {
2328 kfree(map);
2329 return -ENOMEM;
2330 }
2331 em->bdev = (struct block_device *)map;
2332 em->start = start;
2333 em->len = *num_bytes;
2334 em->block_start = 0;
2335 em->block_len = em->len;
2336
2337 em_tree = &extent_root->fs_info->mapping_tree.map_tree;
2338 write_lock(&em_tree->lock);
2339 ret = add_extent_mapping(em_tree, em);
2340 write_unlock(&em_tree->lock);
2341 BUG_ON(ret);
2342 free_extent_map(em);
2343
2344 ret = btrfs_make_block_group(trans, extent_root, 0, type,
2345 BTRFS_FIRST_CHUNK_TREE_OBJECTID,
2346 start, *num_bytes);
2347 BUG_ON(ret);
2348
2349 index = 0;
2350 while (index < map->num_stripes) {
2351 device = map->stripes[index].dev;
2352 dev_offset = map->stripes[index].physical;
2353
2354 ret = btrfs_alloc_dev_extent(trans, device,
2355 info->chunk_root->root_key.objectid,
2356 BTRFS_FIRST_CHUNK_TREE_OBJECTID,
2357 start, dev_offset, calc_size);
2358 BUG_ON(ret);
2359 index++;
2360 }
2361
2362 return 0;
2363 }
2364
2365 static int __finish_chunk_alloc(struct btrfs_trans_handle *trans,
2366 struct btrfs_root *extent_root,
2367 struct map_lookup *map, u64 chunk_offset,
2368 u64 chunk_size, u64 stripe_size)
2369 {
2370 u64 dev_offset;
2371 struct btrfs_key key;
2372 struct btrfs_root *chunk_root = extent_root->fs_info->chunk_root;
2373 struct btrfs_device *device;
2374 struct btrfs_chunk *chunk;
2375 struct btrfs_stripe *stripe;
2376 size_t item_size = btrfs_chunk_item_size(map->num_stripes);
2377 int index = 0;
2378 int ret;
2379
2380 chunk = kzalloc(item_size, GFP_NOFS);
2381 if (!chunk)
2382 return -ENOMEM;
2383
2384 index = 0;
2385 while (index < map->num_stripes) {
2386 device = map->stripes[index].dev;
2387 device->bytes_used += stripe_size;
2388 ret = btrfs_update_device(trans, device);
2389 BUG_ON(ret);
2390 index++;
2391 }
2392
2393 index = 0;
2394 stripe = &chunk->stripe;
2395 while (index < map->num_stripes) {
2396 device = map->stripes[index].dev;
2397 dev_offset = map->stripes[index].physical;
2398
2399 btrfs_set_stack_stripe_devid(stripe, device->devid);
2400 btrfs_set_stack_stripe_offset(stripe, dev_offset);
2401 memcpy(stripe->dev_uuid, device->uuid, BTRFS_UUID_SIZE);
2402 stripe++;
2403 index++;
2404 }
2405
2406 btrfs_set_stack_chunk_length(chunk, chunk_size);
2407 btrfs_set_stack_chunk_owner(chunk, extent_root->root_key.objectid);
2408 btrfs_set_stack_chunk_stripe_len(chunk, map->stripe_len);
2409 btrfs_set_stack_chunk_type(chunk, map->type);
2410 btrfs_set_stack_chunk_num_stripes(chunk, map->num_stripes);
2411 btrfs_set_stack_chunk_io_align(chunk, map->stripe_len);
2412 btrfs_set_stack_chunk_io_width(chunk, map->stripe_len);
2413 btrfs_set_stack_chunk_sector_size(chunk, extent_root->sectorsize);
2414 btrfs_set_stack_chunk_sub_stripes(chunk, map->sub_stripes);
2415
2416 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
2417 key.type = BTRFS_CHUNK_ITEM_KEY;
2418 key.offset = chunk_offset;
2419
2420 ret = btrfs_insert_item(trans, chunk_root, &key, chunk, item_size);
2421 BUG_ON(ret);
2422
2423 if (map->type & BTRFS_BLOCK_GROUP_SYSTEM) {
2424 ret = btrfs_add_system_chunk(trans, chunk_root, &key, chunk,
2425 item_size);
2426 BUG_ON(ret);
2427 }
2428 kfree(chunk);
2429 return 0;
2430 }
2431
2432 /*
2433 * Chunk allocation falls into two parts. The first part does works
2434 * that make the new allocated chunk useable, but not do any operation
2435 * that modifies the chunk tree. The second part does the works that
2436 * require modifying the chunk tree. This division is important for the
2437 * bootstrap process of adding storage to a seed btrfs.
2438 */
2439 int btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
2440 struct btrfs_root *extent_root, u64 type)
2441 {
2442 u64 chunk_offset;
2443 u64 chunk_size;
2444 u64 stripe_size;
2445 struct map_lookup *map;
2446 struct btrfs_root *chunk_root = extent_root->fs_info->chunk_root;
2447 int ret;
2448
2449 ret = find_next_chunk(chunk_root, BTRFS_FIRST_CHUNK_TREE_OBJECTID,
2450 &chunk_offset);
2451 if (ret)
2452 return ret;
2453
2454 ret = __btrfs_alloc_chunk(trans, extent_root, &map, &chunk_size,
2455 &stripe_size, chunk_offset, type);
2456 if (ret)
2457 return ret;
2458
2459 ret = __finish_chunk_alloc(trans, extent_root, map, chunk_offset,
2460 chunk_size, stripe_size);
2461 BUG_ON(ret);
2462 return 0;
2463 }
2464
2465 static noinline int init_first_rw_device(struct btrfs_trans_handle *trans,
2466 struct btrfs_root *root,
2467 struct btrfs_device *device)
2468 {
2469 u64 chunk_offset;
2470 u64 sys_chunk_offset;
2471 u64 chunk_size;
2472 u64 sys_chunk_size;
2473 u64 stripe_size;
2474 u64 sys_stripe_size;
2475 u64 alloc_profile;
2476 struct map_lookup *map;
2477 struct map_lookup *sys_map;
2478 struct btrfs_fs_info *fs_info = root->fs_info;
2479 struct btrfs_root *extent_root = fs_info->extent_root;
2480 int ret;
2481
2482 ret = find_next_chunk(fs_info->chunk_root,
2483 BTRFS_FIRST_CHUNK_TREE_OBJECTID, &chunk_offset);
2484 BUG_ON(ret);
2485
2486 alloc_profile = BTRFS_BLOCK_GROUP_METADATA |
2487 (fs_info->metadata_alloc_profile &
2488 fs_info->avail_metadata_alloc_bits);
2489 alloc_profile = btrfs_reduce_alloc_profile(root, alloc_profile);
2490
2491 ret = __btrfs_alloc_chunk(trans, extent_root, &map, &chunk_size,
2492 &stripe_size, chunk_offset, alloc_profile);
2493 BUG_ON(ret);
2494
2495 sys_chunk_offset = chunk_offset + chunk_size;
2496
2497 alloc_profile = BTRFS_BLOCK_GROUP_SYSTEM |
2498 (fs_info->system_alloc_profile &
2499 fs_info->avail_system_alloc_bits);
2500 alloc_profile = btrfs_reduce_alloc_profile(root, alloc_profile);
2501
2502 ret = __btrfs_alloc_chunk(trans, extent_root, &sys_map,
2503 &sys_chunk_size, &sys_stripe_size,
2504 sys_chunk_offset, alloc_profile);
2505 BUG_ON(ret);
2506
2507 ret = btrfs_add_device(trans, fs_info->chunk_root, device);
2508 BUG_ON(ret);
2509
2510 /*
2511 * Modifying chunk tree needs allocating new blocks from both
2512 * system block group and metadata block group. So we only can
2513 * do operations require modifying the chunk tree after both
2514 * block groups were created.
2515 */
2516 ret = __finish_chunk_alloc(trans, extent_root, map, chunk_offset,
2517 chunk_size, stripe_size);
2518 BUG_ON(ret);
2519
2520 ret = __finish_chunk_alloc(trans, extent_root, sys_map,
2521 sys_chunk_offset, sys_chunk_size,
2522 sys_stripe_size);
2523 BUG_ON(ret);
2524 return 0;
2525 }
2526
2527 int btrfs_chunk_readonly(struct btrfs_root *root, u64 chunk_offset)
2528 {
2529 struct extent_map *em;
2530 struct map_lookup *map;
2531 struct btrfs_mapping_tree *map_tree = &root->fs_info->mapping_tree;
2532 int readonly = 0;
2533 int i;
2534
2535 read_lock(&map_tree->map_tree.lock);
2536 em = lookup_extent_mapping(&map_tree->map_tree, chunk_offset, 1);
2537 read_unlock(&map_tree->map_tree.lock);
2538 if (!em)
2539 return 1;
2540
2541 if (btrfs_test_opt(root, DEGRADED)) {
2542 free_extent_map(em);
2543 return 0;
2544 }
2545
2546 map = (struct map_lookup *)em->bdev;
2547 for (i = 0; i < map->num_stripes; i++) {
2548 if (!map->stripes[i].dev->writeable) {
2549 readonly = 1;
2550 break;
2551 }
2552 }
2553 free_extent_map(em);
2554 return readonly;
2555 }
2556
2557 void btrfs_mapping_init(struct btrfs_mapping_tree *tree)
2558 {
2559 extent_map_tree_init(&tree->map_tree, GFP_NOFS);
2560 }
2561
2562 void btrfs_mapping_tree_free(struct btrfs_mapping_tree *tree)
2563 {
2564 struct extent_map *em;
2565
2566 while (1) {
2567 write_lock(&tree->map_tree.lock);
2568 em = lookup_extent_mapping(&tree->map_tree, 0, (u64)-1);
2569 if (em)
2570 remove_extent_mapping(&tree->map_tree, em);
2571 write_unlock(&tree->map_tree.lock);
2572 if (!em)
2573 break;
2574 kfree(em->bdev);
2575 /* once for us */
2576 free_extent_map(em);
2577 /* once for the tree */
2578 free_extent_map(em);
2579 }
2580 }
2581
2582 int btrfs_num_copies(struct btrfs_mapping_tree *map_tree, u64 logical, u64 len)
2583 {
2584 struct extent_map *em;
2585 struct map_lookup *map;
2586 struct extent_map_tree *em_tree = &map_tree->map_tree;
2587 int ret;
2588
2589 read_lock(&em_tree->lock);
2590 em = lookup_extent_mapping(em_tree, logical, len);
2591 read_unlock(&em_tree->lock);
2592 BUG_ON(!em);
2593
2594 BUG_ON(em->start > logical || em->start + em->len < logical);
2595 map = (struct map_lookup *)em->bdev;
2596 if (map->type & (BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID1))
2597 ret = map->num_stripes;
2598 else if (map->type & BTRFS_BLOCK_GROUP_RAID10)
2599 ret = map->sub_stripes;
2600 else
2601 ret = 1;
2602 free_extent_map(em);
2603 return ret;
2604 }
2605
2606 static int find_live_mirror(struct map_lookup *map, int first, int num,
2607 int optimal)
2608 {
2609 int i;
2610 if (map->stripes[optimal].dev->bdev)
2611 return optimal;
2612 for (i = first; i < first + num; i++) {
2613 if (map->stripes[i].dev->bdev)
2614 return i;
2615 }
2616 /* we couldn't find one that doesn't fail. Just return something
2617 * and the io error handling code will clean up eventually
2618 */
2619 return optimal;
2620 }
2621
2622 static int __btrfs_map_block(struct btrfs_mapping_tree *map_tree, int rw,
2623 u64 logical, u64 *length,
2624 struct btrfs_multi_bio **multi_ret,
2625 int mirror_num, struct page *unplug_page)
2626 {
2627 struct extent_map *em;
2628 struct map_lookup *map;
2629 struct extent_map_tree *em_tree = &map_tree->map_tree;
2630 u64 offset;
2631 u64 stripe_offset;
2632 u64 stripe_nr;
2633 int stripes_allocated = 8;
2634 int stripes_required = 1;
2635 int stripe_index;
2636 int i;
2637 int num_stripes;
2638 int max_errors = 0;
2639 struct btrfs_multi_bio *multi = NULL;
2640
2641 if (multi_ret && !(rw & (1 << BIO_RW)))
2642 stripes_allocated = 1;
2643 again:
2644 if (multi_ret) {
2645 multi = kzalloc(btrfs_multi_bio_size(stripes_allocated),
2646 GFP_NOFS);
2647 if (!multi)
2648 return -ENOMEM;
2649
2650 atomic_set(&multi->error, 0);
2651 }
2652
2653 read_lock(&em_tree->lock);
2654 em = lookup_extent_mapping(em_tree, logical, *length);
2655 read_unlock(&em_tree->lock);
2656
2657 if (!em && unplug_page) {
2658 kfree(multi);
2659 return 0;
2660 }
2661
2662 if (!em) {
2663 printk(KERN_CRIT "unable to find logical %llu len %llu\n",
2664 (unsigned long long)logical,
2665 (unsigned long long)*length);
2666 BUG();
2667 }
2668
2669 BUG_ON(em->start > logical || em->start + em->len < logical);
2670 map = (struct map_lookup *)em->bdev;
2671 offset = logical - em->start;
2672
2673 if (mirror_num > map->num_stripes)
2674 mirror_num = 0;
2675
2676 /* if our multi bio struct is too small, back off and try again */
2677 if (rw & (1 << BIO_RW)) {
2678 if (map->type & (BTRFS_BLOCK_GROUP_RAID1 |
2679 BTRFS_BLOCK_GROUP_DUP)) {
2680 stripes_required = map->num_stripes;
2681 max_errors = 1;
2682 } else if (map->type & BTRFS_BLOCK_GROUP_RAID10) {
2683 stripes_required = map->sub_stripes;
2684 max_errors = 1;
2685 }
2686 }
2687 if (multi_ret && (rw & (1 << BIO_RW)) &&
2688 stripes_allocated < stripes_required) {
2689 stripes_allocated = map->num_stripes;
2690 free_extent_map(em);
2691 kfree(multi);
2692 goto again;
2693 }
2694 stripe_nr = offset;
2695 /*
2696 * stripe_nr counts the total number of stripes we have to stride
2697 * to get to this block
2698 */
2699 do_div(stripe_nr, map->stripe_len);
2700
2701 stripe_offset = stripe_nr * map->stripe_len;
2702 BUG_ON(offset < stripe_offset);
2703
2704 /* stripe_offset is the offset of this block in its stripe*/
2705 stripe_offset = offset - stripe_offset;
2706
2707 if (map->type & (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID1 |
2708 BTRFS_BLOCK_GROUP_RAID10 |
2709 BTRFS_BLOCK_GROUP_DUP)) {
2710 /* we limit the length of each bio to what fits in a stripe */
2711 *length = min_t(u64, em->len - offset,
2712 map->stripe_len - stripe_offset);
2713 } else {
2714 *length = em->len - offset;
2715 }
2716
2717 if (!multi_ret && !unplug_page)
2718 goto out;
2719
2720 num_stripes = 1;
2721 stripe_index = 0;
2722 if (map->type & BTRFS_BLOCK_GROUP_RAID1) {
2723 if (unplug_page || (rw & (1 << BIO_RW)))
2724 num_stripes = map->num_stripes;
2725 else if (mirror_num)
2726 stripe_index = mirror_num - 1;
2727 else {
2728 stripe_index = find_live_mirror(map, 0,
2729 map->num_stripes,
2730 current->pid % map->num_stripes);
2731 }
2732
2733 } else if (map->type & BTRFS_BLOCK_GROUP_DUP) {
2734 if (rw & (1 << BIO_RW))
2735 num_stripes = map->num_stripes;
2736 else if (mirror_num)
2737 stripe_index = mirror_num - 1;
2738
2739 } else if (map->type & BTRFS_BLOCK_GROUP_RAID10) {
2740 int factor = map->num_stripes / map->sub_stripes;
2741
2742 stripe_index = do_div(stripe_nr, factor);
2743 stripe_index *= map->sub_stripes;
2744
2745 if (unplug_page || (rw & (1 << BIO_RW)))
2746 num_stripes = map->sub_stripes;
2747 else if (mirror_num)
2748 stripe_index += mirror_num - 1;
2749 else {
2750 stripe_index = find_live_mirror(map, stripe_index,
2751 map->sub_stripes, stripe_index +
2752 current->pid % map->sub_stripes);
2753 }
2754 } else {
2755 /*
2756 * after this do_div call, stripe_nr is the number of stripes
2757 * on this device we have to walk to find the data, and
2758 * stripe_index is the number of our device in the stripe array
2759 */
2760 stripe_index = do_div(stripe_nr, map->num_stripes);
2761 }
2762 BUG_ON(stripe_index >= map->num_stripes);
2763
2764 for (i = 0; i < num_stripes; i++) {
2765 if (unplug_page) {
2766 struct btrfs_device *device;
2767 struct backing_dev_info *bdi;
2768
2769 device = map->stripes[stripe_index].dev;
2770 if (device->bdev) {
2771 bdi = blk_get_backing_dev_info(device->bdev);
2772 if (bdi->unplug_io_fn)
2773 bdi->unplug_io_fn(bdi, unplug_page);
2774 }
2775 } else {
2776 multi->stripes[i].physical =
2777 map->stripes[stripe_index].physical +
2778 stripe_offset + stripe_nr * map->stripe_len;
2779 multi->stripes[i].dev = map->stripes[stripe_index].dev;
2780 }
2781 stripe_index++;
2782 }
2783 if (multi_ret) {
2784 *multi_ret = multi;
2785 multi->num_stripes = num_stripes;
2786 multi->max_errors = max_errors;
2787 }
2788 out:
2789 free_extent_map(em);
2790 return 0;
2791 }
2792
2793 int btrfs_map_block(struct btrfs_mapping_tree *map_tree, int rw,
2794 u64 logical, u64 *length,
2795 struct btrfs_multi_bio **multi_ret, int mirror_num)
2796 {
2797 return __btrfs_map_block(map_tree, rw, logical, length, multi_ret,
2798 mirror_num, NULL);
2799 }
2800
2801 int btrfs_rmap_block(struct btrfs_mapping_tree *map_tree,
2802 u64 chunk_start, u64 physical, u64 devid,
2803 u64 **logical, int *naddrs, int *stripe_len)
2804 {
2805 struct extent_map_tree *em_tree = &map_tree->map_tree;
2806 struct extent_map *em;
2807 struct map_lookup *map;
2808 u64 *buf;
2809 u64 bytenr;
2810 u64 length;
2811 u64 stripe_nr;
2812 int i, j, nr = 0;
2813
2814 read_lock(&em_tree->lock);
2815 em = lookup_extent_mapping(em_tree, chunk_start, 1);
2816 read_unlock(&em_tree->lock);
2817
2818 BUG_ON(!em || em->start != chunk_start);
2819 map = (struct map_lookup *)em->bdev;
2820
2821 length = em->len;
2822 if (map->type & BTRFS_BLOCK_GROUP_RAID10)
2823 do_div(length, map->num_stripes / map->sub_stripes);
2824 else if (map->type & BTRFS_BLOCK_GROUP_RAID0)
2825 do_div(length, map->num_stripes);
2826
2827 buf = kzalloc(sizeof(u64) * map->num_stripes, GFP_NOFS);
2828 BUG_ON(!buf);
2829
2830 for (i = 0; i < map->num_stripes; i++) {
2831 if (devid && map->stripes[i].dev->devid != devid)
2832 continue;
2833 if (map->stripes[i].physical > physical ||
2834 map->stripes[i].physical + length <= physical)
2835 continue;
2836
2837 stripe_nr = physical - map->stripes[i].physical;
2838 do_div(stripe_nr, map->stripe_len);
2839
2840 if (map->type & BTRFS_BLOCK_GROUP_RAID10) {
2841 stripe_nr = stripe_nr * map->num_stripes + i;
2842 do_div(stripe_nr, map->sub_stripes);
2843 } else if (map->type & BTRFS_BLOCK_GROUP_RAID0) {
2844 stripe_nr = stripe_nr * map->num_stripes + i;
2845 }
2846 bytenr = chunk_start + stripe_nr * map->stripe_len;
2847 WARN_ON(nr >= map->num_stripes);
2848 for (j = 0; j < nr; j++) {
2849 if (buf[j] == bytenr)
2850 break;
2851 }
2852 if (j == nr) {
2853 WARN_ON(nr >= map->num_stripes);
2854 buf[nr++] = bytenr;
2855 }
2856 }
2857
2858 *logical = buf;
2859 *naddrs = nr;
2860 *stripe_len = map->stripe_len;
2861
2862 free_extent_map(em);
2863 return 0;
2864 }
2865
2866 int btrfs_unplug_page(struct btrfs_mapping_tree *map_tree,
2867 u64 logical, struct page *page)
2868 {
2869 u64 length = PAGE_CACHE_SIZE;
2870 return __btrfs_map_block(map_tree, READ, logical, &length,
2871 NULL, 0, page);
2872 }
2873
2874 static void end_bio_multi_stripe(struct bio *bio, int err)
2875 {
2876 struct btrfs_multi_bio *multi = bio->bi_private;
2877 int is_orig_bio = 0;
2878
2879 if (err)
2880 atomic_inc(&multi->error);
2881
2882 if (bio == multi->orig_bio)
2883 is_orig_bio = 1;
2884
2885 if (atomic_dec_and_test(&multi->stripes_pending)) {
2886 if (!is_orig_bio) {
2887 bio_put(bio);
2888 bio = multi->orig_bio;
2889 }
2890 bio->bi_private = multi->private;
2891 bio->bi_end_io = multi->end_io;
2892 /* only send an error to the higher layers if it is
2893 * beyond the tolerance of the multi-bio
2894 */
2895 if (atomic_read(&multi->error) > multi->max_errors) {
2896 err = -EIO;
2897 } else if (err) {
2898 /*
2899 * this bio is actually up to date, we didn't
2900 * go over the max number of errors
2901 */
2902 set_bit(BIO_UPTODATE, &bio->bi_flags);
2903 err = 0;
2904 }
2905 kfree(multi);
2906
2907 bio_endio(bio, err);
2908 } else if (!is_orig_bio) {
2909 bio_put(bio);
2910 }
2911 }
2912
2913 struct async_sched {
2914 struct bio *bio;
2915 int rw;
2916 struct btrfs_fs_info *info;
2917 struct btrfs_work work;
2918 };
2919
2920 /*
2921 * see run_scheduled_bios for a description of why bios are collected for
2922 * async submit.
2923 *
2924 * This will add one bio to the pending list for a device and make sure
2925 * the work struct is scheduled.
2926 */
2927 static noinline int schedule_bio(struct btrfs_root *root,
2928 struct btrfs_device *device,
2929 int rw, struct bio *bio)
2930 {
2931 int should_queue = 1;
2932 struct btrfs_pending_bios *pending_bios;
2933
2934 /* don't bother with additional async steps for reads, right now */
2935 if (!(rw & (1 << BIO_RW))) {
2936 bio_get(bio);
2937 submit_bio(rw, bio);
2938 bio_put(bio);
2939 return 0;
2940 }
2941
2942 /*
2943 * nr_async_bios allows us to reliably return congestion to the
2944 * higher layers. Otherwise, the async bio makes it appear we have
2945 * made progress against dirty pages when we've really just put it
2946 * on a queue for later
2947 */
2948 atomic_inc(&root->fs_info->nr_async_bios);
2949 WARN_ON(bio->bi_next);
2950 bio->bi_next = NULL;
2951 bio->bi_rw |= rw;
2952
2953 spin_lock(&device->io_lock);
2954 if (bio_rw_flagged(bio, BIO_RW_SYNCIO))
2955 pending_bios = &device->pending_sync_bios;
2956 else
2957 pending_bios = &device->pending_bios;
2958
2959 if (pending_bios->tail)
2960 pending_bios->tail->bi_next = bio;
2961
2962 pending_bios->tail = bio;
2963 if (!pending_bios->head)
2964 pending_bios->head = bio;
2965 if (device->running_pending)
2966 should_queue = 0;
2967
2968 spin_unlock(&device->io_lock);
2969
2970 if (should_queue)
2971 btrfs_queue_worker(&root->fs_info->submit_workers,
2972 &device->work);
2973 return 0;
2974 }
2975
2976 int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio,
2977 int mirror_num, int async_submit)
2978 {
2979 struct btrfs_mapping_tree *map_tree;
2980 struct btrfs_device *dev;
2981 struct bio *first_bio = bio;
2982 u64 logical = (u64)bio->bi_sector << 9;
2983 u64 length = 0;
2984 u64 map_length;
2985 struct btrfs_multi_bio *multi = NULL;
2986 int ret;
2987 int dev_nr = 0;
2988 int total_devs = 1;
2989
2990 length = bio->bi_size;
2991 map_tree = &root->fs_info->mapping_tree;
2992 map_length = length;
2993
2994 ret = btrfs_map_block(map_tree, rw, logical, &map_length, &multi,
2995 mirror_num);
2996 BUG_ON(ret);
2997
2998 total_devs = multi->num_stripes;
2999 if (map_length < length) {
3000 printk(KERN_CRIT "mapping failed logical %llu bio len %llu "
3001 "len %llu\n", (unsigned long long)logical,
3002 (unsigned long long)length,
3003 (unsigned long long)map_length);
3004 BUG();
3005 }
3006 multi->end_io = first_bio->bi_end_io;
3007 multi->private = first_bio->bi_private;
3008 multi->orig_bio = first_bio;
3009 atomic_set(&multi->stripes_pending, multi->num_stripes);
3010
3011 while (dev_nr < total_devs) {
3012 if (total_devs > 1) {
3013 if (dev_nr < total_devs - 1) {
3014 bio = bio_clone(first_bio, GFP_NOFS);
3015 BUG_ON(!bio);
3016 } else {
3017 bio = first_bio;
3018 }
3019 bio->bi_private = multi;
3020 bio->bi_end_io = end_bio_multi_stripe;
3021 }
3022 bio->bi_sector = multi->stripes[dev_nr].physical >> 9;
3023 dev = multi->stripes[dev_nr].dev;
3024 BUG_ON(rw == WRITE && !dev->writeable);
3025 if (dev && dev->bdev) {
3026 bio->bi_bdev = dev->bdev;
3027 if (async_submit)
3028 schedule_bio(root, dev, rw, bio);
3029 else
3030 submit_bio(rw, bio);
3031 } else {
3032 bio->bi_bdev = root->fs_info->fs_devices->latest_bdev;
3033 bio->bi_sector = logical >> 9;
3034 bio_endio(bio, -EIO);
3035 }
3036 dev_nr++;
3037 }
3038 if (total_devs == 1)
3039 kfree(multi);
3040 return 0;
3041 }
3042
3043 struct btrfs_device *btrfs_find_device(struct btrfs_root *root, u64 devid,
3044 u8 *uuid, u8 *fsid)
3045 {
3046 struct btrfs_device *device;
3047 struct btrfs_fs_devices *cur_devices;
3048
3049 cur_devices = root->fs_info->fs_devices;
3050 while (cur_devices) {
3051 if (!fsid ||
3052 !memcmp(cur_devices->fsid, fsid, BTRFS_UUID_SIZE)) {
3053 device = __find_device(&cur_devices->devices,
3054 devid, uuid);
3055 if (device)
3056 return device;
3057 }
3058 cur_devices = cur_devices->seed;
3059 }
3060 return NULL;
3061 }
3062
3063 static struct btrfs_device *add_missing_dev(struct btrfs_root *root,
3064 u64 devid, u8 *dev_uuid)
3065 {
3066 struct btrfs_device *device;
3067 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
3068
3069 device = kzalloc(sizeof(*device), GFP_NOFS);
3070 if (!device)
3071 return NULL;
3072 list_add(&device->dev_list,
3073 &fs_devices->devices);
3074 device->barriers = 1;
3075 device->dev_root = root->fs_info->dev_root;
3076 device->devid = devid;
3077 device->work.func = pending_bios_fn;
3078 device->fs_devices = fs_devices;
3079 fs_devices->num_devices++;
3080 spin_lock_init(&device->io_lock);
3081 INIT_LIST_HEAD(&device->dev_alloc_list);
3082 memcpy(device->uuid, dev_uuid, BTRFS_UUID_SIZE);
3083 return device;
3084 }
3085
3086 static int read_one_chunk(struct btrfs_root *root, struct btrfs_key *key,
3087 struct extent_buffer *leaf,
3088 struct btrfs_chunk *chunk)
3089 {
3090 struct btrfs_mapping_tree *map_tree = &root->fs_info->mapping_tree;
3091 struct map_lookup *map;
3092 struct extent_map *em;
3093 u64 logical;
3094 u64 length;
3095 u64 devid;
3096 u8 uuid[BTRFS_UUID_SIZE];
3097 int num_stripes;
3098 int ret;
3099 int i;
3100
3101 logical = key->offset;
3102 length = btrfs_chunk_length(leaf, chunk);
3103
3104 read_lock(&map_tree->map_tree.lock);
3105 em = lookup_extent_mapping(&map_tree->map_tree, logical, 1);
3106 read_unlock(&map_tree->map_tree.lock);
3107
3108 /* already mapped? */
3109 if (em && em->start <= logical && em->start + em->len > logical) {
3110 free_extent_map(em);
3111 return 0;
3112 } else if (em) {
3113 free_extent_map(em);
3114 }
3115
3116 em = alloc_extent_map(GFP_NOFS);
3117 if (!em)
3118 return -ENOMEM;
3119 num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
3120 map = kmalloc(map_lookup_size(num_stripes), GFP_NOFS);
3121 if (!map) {
3122 free_extent_map(em);
3123 return -ENOMEM;
3124 }
3125
3126 em->bdev = (struct block_device *)map;
3127 em->start = logical;
3128 em->len = length;
3129 em->block_start = 0;
3130 em->block_len = em->len;
3131
3132 map->num_stripes = num_stripes;
3133 map->io_width = btrfs_chunk_io_width(leaf, chunk);
3134 map->io_align = btrfs_chunk_io_align(leaf, chunk);
3135 map->sector_size = btrfs_chunk_sector_size(leaf, chunk);
3136 map->stripe_len = btrfs_chunk_stripe_len(leaf, chunk);
3137 map->type = btrfs_chunk_type(leaf, chunk);
3138 map->sub_stripes = btrfs_chunk_sub_stripes(leaf, chunk);
3139 for (i = 0; i < num_stripes; i++) {
3140 map->stripes[i].physical =
3141 btrfs_stripe_offset_nr(leaf, chunk, i);
3142 devid = btrfs_stripe_devid_nr(leaf, chunk, i);
3143 read_extent_buffer(leaf, uuid, (unsigned long)
3144 btrfs_stripe_dev_uuid_nr(chunk, i),
3145 BTRFS_UUID_SIZE);
3146 map->stripes[i].dev = btrfs_find_device(root, devid, uuid,
3147 NULL);
3148 if (!map->stripes[i].dev && !btrfs_test_opt(root, DEGRADED)) {
3149 kfree(map);
3150 free_extent_map(em);
3151 return -EIO;
3152 }
3153 if (!map->stripes[i].dev) {
3154 map->stripes[i].dev =
3155 add_missing_dev(root, devid, uuid);
3156 if (!map->stripes[i].dev) {
3157 kfree(map);
3158 free_extent_map(em);
3159 return -EIO;
3160 }
3161 }
3162 map->stripes[i].dev->in_fs_metadata = 1;
3163 }
3164
3165 write_lock(&map_tree->map_tree.lock);
3166 ret = add_extent_mapping(&map_tree->map_tree, em);
3167 write_unlock(&map_tree->map_tree.lock);
3168 BUG_ON(ret);
3169 free_extent_map(em);
3170
3171 return 0;
3172 }
3173
3174 static int fill_device_from_item(struct extent_buffer *leaf,
3175 struct btrfs_dev_item *dev_item,
3176 struct btrfs_device *device)
3177 {
3178 unsigned long ptr;
3179
3180 device->devid = btrfs_device_id(leaf, dev_item);
3181 device->disk_total_bytes = btrfs_device_total_bytes(leaf, dev_item);
3182 device->total_bytes = device->disk_total_bytes;
3183 device->bytes_used = btrfs_device_bytes_used(leaf, dev_item);
3184 device->type = btrfs_device_type(leaf, dev_item);
3185 device->io_align = btrfs_device_io_align(leaf, dev_item);
3186 device->io_width = btrfs_device_io_width(leaf, dev_item);
3187 device->sector_size = btrfs_device_sector_size(leaf, dev_item);
3188
3189 ptr = (unsigned long)btrfs_device_uuid(dev_item);
3190 read_extent_buffer(leaf, device->uuid, ptr, BTRFS_UUID_SIZE);
3191
3192 return 0;
3193 }
3194
3195 static int open_seed_devices(struct btrfs_root *root, u8 *fsid)
3196 {
3197 struct btrfs_fs_devices *fs_devices;
3198 int ret;
3199
3200 mutex_lock(&uuid_mutex);
3201
3202 fs_devices = root->fs_info->fs_devices->seed;
3203 while (fs_devices) {
3204 if (!memcmp(fs_devices->fsid, fsid, BTRFS_UUID_SIZE)) {
3205 ret = 0;
3206 goto out;
3207 }
3208 fs_devices = fs_devices->seed;
3209 }
3210
3211 fs_devices = find_fsid(fsid);
3212 if (!fs_devices) {
3213 ret = -ENOENT;
3214 goto out;
3215 }
3216
3217 fs_devices = clone_fs_devices(fs_devices);
3218 if (IS_ERR(fs_devices)) {
3219 ret = PTR_ERR(fs_devices);
3220 goto out;
3221 }
3222
3223 ret = __btrfs_open_devices(fs_devices, FMODE_READ,
3224 root->fs_info->bdev_holder);
3225 if (ret)
3226 goto out;
3227
3228 if (!fs_devices->seeding) {
3229 __btrfs_close_devices(fs_devices);
3230 free_fs_devices(fs_devices);
3231 ret = -EINVAL;
3232 goto out;
3233 }
3234
3235 fs_devices->seed = root->fs_info->fs_devices->seed;
3236 root->fs_info->fs_devices->seed = fs_devices;
3237 out:
3238 mutex_unlock(&uuid_mutex);
3239 return ret;
3240 }
3241
3242 static int read_one_dev(struct btrfs_root *root,
3243 struct extent_buffer *leaf,
3244 struct btrfs_dev_item *dev_item)
3245 {
3246 struct btrfs_device *device;
3247 u64 devid;
3248 int ret;
3249 u8 fs_uuid[BTRFS_UUID_SIZE];
3250 u8 dev_uuid[BTRFS_UUID_SIZE];
3251
3252 devid = btrfs_device_id(leaf, dev_item);
3253 read_extent_buffer(leaf, dev_uuid,
3254 (unsigned long)btrfs_device_uuid(dev_item),
3255 BTRFS_UUID_SIZE);
3256 read_extent_buffer(leaf, fs_uuid,
3257 (unsigned long)btrfs_device_fsid(dev_item),
3258 BTRFS_UUID_SIZE);
3259
3260 if (memcmp(fs_uuid, root->fs_info->fsid, BTRFS_UUID_SIZE)) {
3261 ret = open_seed_devices(root, fs_uuid);
3262 if (ret && !btrfs_test_opt(root, DEGRADED))
3263 return ret;
3264 }
3265
3266 device = btrfs_find_device(root, devid, dev_uuid, fs_uuid);
3267 if (!device || !device->bdev) {
3268 if (!btrfs_test_opt(root, DEGRADED))
3269 return -EIO;
3270
3271 if (!device) {
3272 printk(KERN_WARNING "warning devid %llu missing\n",
3273 (unsigned long long)devid);
3274 device = add_missing_dev(root, devid, dev_uuid);
3275 if (!device)
3276 return -ENOMEM;
3277 }
3278 }
3279
3280 if (device->fs_devices != root->fs_info->fs_devices) {
3281 BUG_ON(device->writeable);
3282 if (device->generation !=
3283 btrfs_device_generation(leaf, dev_item))
3284 return -EINVAL;
3285 }
3286
3287 fill_device_from_item(leaf, dev_item, device);
3288 device->dev_root = root->fs_info->dev_root;
3289 device->in_fs_metadata = 1;
3290 if (device->writeable)
3291 device->fs_devices->total_rw_bytes += device->total_bytes;
3292 ret = 0;
3293 return ret;
3294 }
3295
3296 int btrfs_read_super_device(struct btrfs_root *root, struct extent_buffer *buf)
3297 {
3298 struct btrfs_dev_item *dev_item;
3299
3300 dev_item = (struct btrfs_dev_item *)offsetof(struct btrfs_super_block,
3301 dev_item);
3302 return read_one_dev(root, buf, dev_item);
3303 }
3304
3305 int btrfs_read_sys_array(struct btrfs_root *root)
3306 {
3307 struct btrfs_super_block *super_copy = &root->fs_info->super_copy;
3308 struct extent_buffer *sb;
3309 struct btrfs_disk_key *disk_key;
3310 struct btrfs_chunk *chunk;
3311 u8 *ptr;
3312 unsigned long sb_ptr;
3313 int ret = 0;
3314 u32 num_stripes;
3315 u32 array_size;
3316 u32 len = 0;
3317 u32 cur;
3318 struct btrfs_key key;
3319
3320 sb = btrfs_find_create_tree_block(root, BTRFS_SUPER_INFO_OFFSET,
3321 BTRFS_SUPER_INFO_SIZE);
3322 if (!sb)
3323 return -ENOMEM;
3324 btrfs_set_buffer_uptodate(sb);
3325 btrfs_set_buffer_lockdep_class(sb, 0);
3326
3327 write_extent_buffer(sb, super_copy, 0, BTRFS_SUPER_INFO_SIZE);
3328 array_size = btrfs_super_sys_array_size(super_copy);
3329
3330 ptr = super_copy->sys_chunk_array;
3331 sb_ptr = offsetof(struct btrfs_super_block, sys_chunk_array);
3332 cur = 0;
3333
3334 while (cur < array_size) {
3335 disk_key = (struct btrfs_disk_key *)ptr;
3336 btrfs_disk_key_to_cpu(&key, disk_key);
3337
3338 len = sizeof(*disk_key); ptr += len;
3339 sb_ptr += len;
3340 cur += len;
3341
3342 if (key.type == BTRFS_CHUNK_ITEM_KEY) {
3343 chunk = (struct btrfs_chunk *)sb_ptr;
3344 ret = read_one_chunk(root, &key, sb, chunk);
3345 if (ret)
3346 break;
3347 num_stripes = btrfs_chunk_num_stripes(sb, chunk);
3348 len = btrfs_chunk_item_size(num_stripes);
3349 } else {
3350 ret = -EIO;
3351 break;
3352 }
3353 ptr += len;
3354 sb_ptr += len;
3355 cur += len;
3356 }
3357 free_extent_buffer(sb);
3358 return ret;
3359 }
3360
3361 int btrfs_read_chunk_tree(struct btrfs_root *root)
3362 {
3363 struct btrfs_path *path;
3364 struct extent_buffer *leaf;
3365 struct btrfs_key key;
3366 struct btrfs_key found_key;
3367 int ret;
3368 int slot;
3369
3370 root = root->fs_info->chunk_root;
3371
3372 path = btrfs_alloc_path();
3373 if (!path)
3374 return -ENOMEM;
3375
3376 /* first we search for all of the device items, and then we
3377 * read in all of the chunk items. This way we can create chunk
3378 * mappings that reference all of the devices that are afound
3379 */
3380 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
3381 key.offset = 0;
3382 key.type = 0;
3383 again:
3384 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
3385 while (1) {
3386 leaf = path->nodes[0];
3387 slot = path->slots[0];
3388 if (slot >= btrfs_header_nritems(leaf)) {
3389 ret = btrfs_next_leaf(root, path);
3390 if (ret == 0)
3391 continue;
3392 if (ret < 0)
3393 goto error;
3394 break;
3395 }
3396 btrfs_item_key_to_cpu(leaf, &found_key, slot);
3397 if (key.objectid == BTRFS_DEV_ITEMS_OBJECTID) {
3398 if (found_key.objectid != BTRFS_DEV_ITEMS_OBJECTID)
3399 break;
3400 if (found_key.type == BTRFS_DEV_ITEM_KEY) {
3401 struct btrfs_dev_item *dev_item;
3402 dev_item = btrfs_item_ptr(leaf, slot,
3403 struct btrfs_dev_item);
3404 ret = read_one_dev(root, leaf, dev_item);
3405 if (ret)
3406 goto error;
3407 }
3408 } else if (found_key.type == BTRFS_CHUNK_ITEM_KEY) {
3409 struct btrfs_chunk *chunk;
3410 chunk = btrfs_item_ptr(leaf, slot, struct btrfs_chunk);
3411 ret = read_one_chunk(root, &found_key, leaf, chunk);
3412 if (ret)
3413 goto error;
3414 }
3415 path->slots[0]++;
3416 }
3417 if (key.objectid == BTRFS_DEV_ITEMS_OBJECTID) {
3418 key.objectid = 0;
3419 btrfs_release_path(root, path);
3420 goto again;
3421 }
3422 ret = 0;
3423 error:
3424 btrfs_free_path(path);
3425 return ret;
3426 }
Linux 2.6 ibm-acpi/thinkpad-acpi driver git tree