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