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Print the root generation in btrfs-debug-tree
[btrfs-progs-unstable/devel.git] / volumes.c
blob37f68df0b04995fdb9f35ad9de5781993558d9f7
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 #define _XOPEN_SOURCE 600
19 #define __USE_XOPEN2K
20 #include <stdio.h>
21 #include <stdlib.h>
22 #include <sys/types.h>
23 #include <sys/stat.h>
24 #include <uuid/uuid.h>
25 #include <fcntl.h>
26 #include <unistd.h>
27 #include "ctree.h"
28 #include "disk-io.h"
29 #include "transaction.h"
30 #include "print-tree.h"
31 #include "volumes.h"
32
33 struct stripe {
34 struct btrfs_device *dev;
35 u64 physical;
36 };
37
38 struct map_lookup {
39 struct cache_extent ce;
40 u64 type;
41 int io_align;
42 int io_width;
43 int stripe_len;
44 int sector_size;
45 int num_stripes;
46 int sub_stripes;
47 struct btrfs_bio_stripe stripes[];
48 };
49
50 #define map_lookup_size(n) (sizeof(struct map_lookup) + \
51 (sizeof(struct btrfs_bio_stripe) * (n)))
52
53 static LIST_HEAD(fs_uuids);
54
55 static struct btrfs_device *__find_device(struct list_head *head, u64 devid,
56 u8 *uuid)
57 {
58 struct btrfs_device *dev;
59 struct list_head *cur;
60
61 list_for_each(cur, head) {
62 dev = list_entry(cur, struct btrfs_device, dev_list);
63 if (dev->devid == devid &&
64 !memcmp(dev->uuid, uuid, BTRFS_UUID_SIZE)) {
65 return dev;
66 }
67 }
68 return NULL;
69 }
70
71 static struct btrfs_fs_devices *find_fsid(u8 *fsid)
72 {
73 struct list_head *cur;
74 struct btrfs_fs_devices *fs_devices;
75
76 list_for_each(cur, &fs_uuids) {
77 fs_devices = list_entry(cur, struct btrfs_fs_devices, list);
78 if (memcmp(fsid, fs_devices->fsid, BTRFS_FSID_SIZE) == 0)
79 return fs_devices;
80 }
81 return NULL;
82 }
83
84 static int device_list_add(const char *path,
85 struct btrfs_super_block *disk_super,
86 u64 devid, struct btrfs_fs_devices **fs_devices_ret)
87 {
88 struct btrfs_device *device;
89 struct btrfs_fs_devices *fs_devices;
90 u64 found_transid = btrfs_super_generation(disk_super);
91
92 fs_devices = find_fsid(disk_super->fsid);
93 if (!fs_devices) {
94 fs_devices = kzalloc(sizeof(*fs_devices), GFP_NOFS);
95 if (!fs_devices)
96 return -ENOMEM;
97 INIT_LIST_HEAD(&fs_devices->devices);
98 list_add(&fs_devices->list, &fs_uuids);
99 memcpy(fs_devices->fsid, disk_super->fsid, BTRFS_FSID_SIZE);
100 fs_devices->latest_devid = devid;
101 fs_devices->latest_trans = found_transid;
102 fs_devices->lowest_devid = (u64)-1;
103 device = NULL;
104 } else {
105 device = __find_device(&fs_devices->devices, devid,
106 disk_super->dev_item.uuid);
107 }
108 if (!device) {
109 device = kzalloc(sizeof(*device), GFP_NOFS);
110 if (!device) {
111 /* we can safely leave the fs_devices entry around */
112 return -ENOMEM;
113 }
114 device->devid = devid;
115 memcpy(device->uuid, disk_super->dev_item.uuid,
116 BTRFS_UUID_SIZE);
117 device->name = kstrdup(path, GFP_NOFS);
118 if (!device->name) {
119 kfree(device);
120 return -ENOMEM;
121 }
122 device->label = kstrdup(disk_super->label, GFP_NOFS);
123 device->total_devs = btrfs_super_num_devices(disk_super);
124 device->super_bytes_used = btrfs_super_bytes_used(disk_super);
125 device->total_bytes =
126 btrfs_stack_device_total_bytes(&disk_super->dev_item);
127 device->bytes_used =
128 btrfs_stack_device_bytes_used(&disk_super->dev_item);
129 list_add(&device->dev_list, &fs_devices->devices);
130 device->fs_devices = fs_devices;
131 }
132
133 if (found_transid > fs_devices->latest_trans) {
134 fs_devices->latest_devid = devid;
135 fs_devices->latest_trans = found_transid;
136 }
137 if (fs_devices->lowest_devid > devid) {
138 fs_devices->lowest_devid = devid;
139 }
140 *fs_devices_ret = fs_devices;
141 return 0;
142 }
143
144 int btrfs_close_devices(struct btrfs_fs_devices *fs_devices)
145 {
146 struct btrfs_fs_devices *seed_devices;
147 struct list_head *cur;
148 struct btrfs_device *device;
149 again:
150 list_for_each(cur, &fs_devices->devices) {
151 device = list_entry(cur, struct btrfs_device, dev_list);
152 close(device->fd);
153 device->fd = -1;
154 device->writeable = 0;
155 }
156
157 seed_devices = fs_devices->seed;
158 fs_devices->seed = NULL;
159 if (seed_devices) {
160 fs_devices = seed_devices;
161 goto again;
162 }
163
164 return 0;
165 }
166
167 int btrfs_open_devices(struct btrfs_fs_devices *fs_devices, int flags)
168 {
169 int fd;
170 struct list_head *head = &fs_devices->devices;
171 struct list_head *cur;
172 struct btrfs_device *device;
173 int ret;
174
175 list_for_each(cur, head) {
176 device = list_entry(cur, struct btrfs_device, dev_list);
177
178 fd = open(device->name, flags);
179 if (fd < 0) {
180 ret = -errno;
181 goto fail;
182 }
183
184 if (device->devid == fs_devices->latest_devid)
185 fs_devices->latest_bdev = fd;
186 if (device->devid == fs_devices->lowest_devid)
187 fs_devices->lowest_bdev = fd;
188 device->fd = fd;
189 if (flags == O_RDWR)
190 device->writeable = 1;
191 }
192 return 0;
193 fail:
194 btrfs_close_devices(fs_devices);
195 return ret;
196 }
197
198 int btrfs_scan_one_device(int fd, const char *path,
199 struct btrfs_fs_devices **fs_devices_ret,
200 u64 *total_devs, u64 super_offset)
201 {
202 struct btrfs_super_block *disk_super;
203 char *buf;
204 int ret;
205 u64 devid;
206 char uuidbuf[37];
207
208 buf = malloc(4096);
209 if (!buf) {
210 ret = -ENOMEM;
211 goto error;
212 }
213 disk_super = (struct btrfs_super_block *)buf;
214 ret = btrfs_read_dev_super(fd, disk_super, super_offset);
215 if (ret < 0) {
216 ret = -EIO;
217 goto error_brelse;
218 }
219 devid = le64_to_cpu(disk_super->dev_item.devid);
220 if (btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_METADUMP)
221 *total_devs = 1;
222 else
223 *total_devs = btrfs_super_num_devices(disk_super);
224 uuid_unparse(disk_super->fsid, uuidbuf);
225
226 ret = device_list_add(path, disk_super, devid, fs_devices_ret);
227
228 error_brelse:
229 free(buf);
230 error:
231 return ret;
232 }
233
234 /*
235 * this uses a pretty simple search, the expectation is that it is
236 * called very infrequently and that a given device has a small number
237 * of extents
238 */
239 static int find_free_dev_extent(struct btrfs_trans_handle *trans,
240 struct btrfs_device *device,
241 struct btrfs_path *path,
242 u64 num_bytes, u64 *start)
243 {
244 struct btrfs_key key;
245 struct btrfs_root *root = device->dev_root;
246 struct btrfs_dev_extent *dev_extent = NULL;
247 u64 hole_size = 0;
248 u64 last_byte = 0;
249 u64 search_start = 0;
250 u64 search_end = device->total_bytes;
251 int ret;
252 int slot = 0;
253 int start_found;
254 struct extent_buffer *l;
255
256 start_found = 0;
257 path->reada = 2;
258
259 /* FIXME use last free of some kind */
260
261 /* we don't want to overwrite the superblock on the drive,
262 * so we make sure to start at an offset of at least 1MB
263 */
264 search_start = max((u64)1024 * 1024, search_start);
265
266 if (root->fs_info->alloc_start + num_bytes <= device->total_bytes)
267 search_start = max(root->fs_info->alloc_start, search_start);
268
269 key.objectid = device->devid;
270 key.offset = search_start;
271 key.type = BTRFS_DEV_EXTENT_KEY;
272 ret = btrfs_search_slot(trans, root, &key, path, 0, 0);
273 if (ret < 0)
274 goto error;
275 ret = btrfs_previous_item(root, path, 0, key.type);
276 if (ret < 0)
277 goto error;
278 l = path->nodes[0];
279 btrfs_item_key_to_cpu(l, &key, path->slots[0]);
280 while (1) {
281 l = path->nodes[0];
282 slot = path->slots[0];
283 if (slot >= btrfs_header_nritems(l)) {
284 ret = btrfs_next_leaf(root, path);
285 if (ret == 0)
286 continue;
287 if (ret < 0)
288 goto error;
289 no_more_items:
290 if (!start_found) {
291 if (search_start >= search_end) {
292 ret = -ENOSPC;
293 goto error;
294 }
295 *start = search_start;
296 start_found = 1;
297 goto check_pending;
298 }
299 *start = last_byte > search_start ?
300 last_byte : search_start;
301 if (search_end <= *start) {
302 ret = -ENOSPC;
303 goto error;
304 }
305 goto check_pending;
306 }
307 btrfs_item_key_to_cpu(l, &key, slot);
308
309 if (key.objectid < device->devid)
310 goto next;
311
312 if (key.objectid > device->devid)
313 goto no_more_items;
314
315 if (key.offset >= search_start && key.offset > last_byte &&
316 start_found) {
317 if (last_byte < search_start)
318 last_byte = search_start;
319 hole_size = key.offset - last_byte;
320 if (key.offset > last_byte &&
321 hole_size >= num_bytes) {
322 *start = last_byte;
323 goto check_pending;
324 }
325 }
326 if (btrfs_key_type(&key) != BTRFS_DEV_EXTENT_KEY) {
327 goto next;
328 }
329
330 start_found = 1;
331 dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent);
332 last_byte = key.offset + btrfs_dev_extent_length(l, dev_extent);
333 next:
334 path->slots[0]++;
335 cond_resched();
336 }
337 check_pending:
338 /* we have to make sure we didn't find an extent that has already
339 * been allocated by the map tree or the original allocation
340 */
341 btrfs_release_path(root, path);
342 BUG_ON(*start < search_start);
343
344 if (*start + num_bytes > search_end) {
345 ret = -ENOSPC;
346 goto error;
347 }
348 /* check for pending inserts here */
349 return 0;
350
351 error:
352 btrfs_release_path(root, path);
353 return ret;
354 }
355
356 int btrfs_alloc_dev_extent(struct btrfs_trans_handle *trans,
357 struct btrfs_device *device,
358 u64 chunk_tree, u64 chunk_objectid,
359 u64 chunk_offset,
360 u64 num_bytes, u64 *start)
361 {
362 int ret;
363 struct btrfs_path *path;
364 struct btrfs_root *root = device->dev_root;
365 struct btrfs_dev_extent *extent;
366 struct extent_buffer *leaf;
367 struct btrfs_key key;
368
369 path = btrfs_alloc_path();
370 if (!path)
371 return -ENOMEM;
372
373 ret = find_free_dev_extent(trans, device, path, num_bytes, start);
374 if (ret) {
375 goto err;
376 }
377
378 key.objectid = device->devid;
379 key.offset = *start;
380 key.type = BTRFS_DEV_EXTENT_KEY;
381 ret = btrfs_insert_empty_item(trans, root, path, &key,
382 sizeof(*extent));
383 BUG_ON(ret);
384
385 leaf = path->nodes[0];
386 extent = btrfs_item_ptr(leaf, path->slots[0],
387 struct btrfs_dev_extent);
388 btrfs_set_dev_extent_chunk_tree(leaf, extent, chunk_tree);
389 btrfs_set_dev_extent_chunk_objectid(leaf, extent, chunk_objectid);
390 btrfs_set_dev_extent_chunk_offset(leaf, extent, chunk_offset);
391
392 write_extent_buffer(leaf, root->fs_info->chunk_tree_uuid,
393 (unsigned long)btrfs_dev_extent_chunk_tree_uuid(extent),
394 BTRFS_UUID_SIZE);
395
396 btrfs_set_dev_extent_length(leaf, extent, num_bytes);
397 btrfs_mark_buffer_dirty(leaf);
398 err:
399 btrfs_free_path(path);
400 return ret;
401 }
402
403 static int find_next_chunk(struct btrfs_root *root, u64 objectid, u64 *offset)
404 {
405 struct btrfs_path *path;
406 int ret;
407 struct btrfs_key key;
408 struct btrfs_chunk *chunk;
409 struct btrfs_key found_key;
410
411 path = btrfs_alloc_path();
412 BUG_ON(!path);
413
414 key.objectid = objectid;
415 key.offset = (u64)-1;
416 key.type = BTRFS_CHUNK_ITEM_KEY;
417
418 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
419 if (ret < 0)
420 goto error;
421
422 BUG_ON(ret == 0);
423
424 ret = btrfs_previous_item(root, path, 0, BTRFS_CHUNK_ITEM_KEY);
425 if (ret) {
426 *offset = 0;
427 } else {
428 btrfs_item_key_to_cpu(path->nodes[0], &found_key,
429 path->slots[0]);
430 if (found_key.objectid != objectid)
431 *offset = 0;
432 else {
433 chunk = btrfs_item_ptr(path->nodes[0], path->slots[0],
434 struct btrfs_chunk);
435 *offset = found_key.offset +
436 btrfs_chunk_length(path->nodes[0], chunk);
437 }
438 }
439 ret = 0;
440 error:
441 btrfs_free_path(path);
442 return ret;
443 }
444
445 static int find_next_devid(struct btrfs_root *root, struct btrfs_path *path,
446 u64 *objectid)
447 {
448 int ret;
449 struct btrfs_key key;
450 struct btrfs_key found_key;
451
452 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
453 key.type = BTRFS_DEV_ITEM_KEY;
454 key.offset = (u64)-1;
455
456 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
457 if (ret < 0)
458 goto error;
459
460 BUG_ON(ret == 0);
461
462 ret = btrfs_previous_item(root, path, BTRFS_DEV_ITEMS_OBJECTID,
463 BTRFS_DEV_ITEM_KEY);
464 if (ret) {
465 *objectid = 1;
466 } else {
467 btrfs_item_key_to_cpu(path->nodes[0], &found_key,
468 path->slots[0]);
469 *objectid = found_key.offset + 1;
470 }
471 ret = 0;
472 error:
473 btrfs_release_path(root, path);
474 return ret;
475 }
476
477 /*
478 * the device information is stored in the chunk root
479 * the btrfs_device struct should be fully filled in
480 */
481 int btrfs_add_device(struct btrfs_trans_handle *trans,
482 struct btrfs_root *root,
483 struct btrfs_device *device)
484 {
485 int ret;
486 struct btrfs_path *path;
487 struct btrfs_dev_item *dev_item;
488 struct extent_buffer *leaf;
489 struct btrfs_key key;
490 unsigned long ptr;
491 u64 free_devid = 0;
492
493 root = root->fs_info->chunk_root;
494
495 path = btrfs_alloc_path();
496 if (!path)
497 return -ENOMEM;
498
499 ret = find_next_devid(root, path, &free_devid);
500 if (ret)
501 goto out;
502
503 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
504 key.type = BTRFS_DEV_ITEM_KEY;
505 key.offset = free_devid;
506
507 ret = btrfs_insert_empty_item(trans, root, path, &key,
508 sizeof(*dev_item));
509 if (ret)
510 goto out;
511
512 leaf = path->nodes[0];
513 dev_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dev_item);
514
515 device->devid = free_devid;
516 btrfs_set_device_id(leaf, dev_item, device->devid);
517 btrfs_set_device_generation(leaf, dev_item, 0);
518 btrfs_set_device_type(leaf, dev_item, device->type);
519 btrfs_set_device_io_align(leaf, dev_item, device->io_align);
520 btrfs_set_device_io_width(leaf, dev_item, device->io_width);
521 btrfs_set_device_sector_size(leaf, dev_item, device->sector_size);
522 btrfs_set_device_total_bytes(leaf, dev_item, device->total_bytes);
523 btrfs_set_device_bytes_used(leaf, dev_item, device->bytes_used);
524 btrfs_set_device_group(leaf, dev_item, 0);
525 btrfs_set_device_seek_speed(leaf, dev_item, 0);
526 btrfs_set_device_bandwidth(leaf, dev_item, 0);
527 btrfs_set_device_start_offset(leaf, dev_item, 0);
528
529 ptr = (unsigned long)btrfs_device_uuid(dev_item);
530 write_extent_buffer(leaf, device->uuid, ptr, BTRFS_UUID_SIZE);
531 ptr = (unsigned long)btrfs_device_fsid(dev_item);
532 write_extent_buffer(leaf, root->fs_info->fsid, ptr, BTRFS_UUID_SIZE);
533 btrfs_mark_buffer_dirty(leaf);
534 ret = 0;
535
536 out:
537 btrfs_free_path(path);
538 return ret;
539 }
540
541 int btrfs_update_device(struct btrfs_trans_handle *trans,
542 struct btrfs_device *device)
543 {
544 int ret;
545 struct btrfs_path *path;
546 struct btrfs_root *root;
547 struct btrfs_dev_item *dev_item;
548 struct extent_buffer *leaf;
549 struct btrfs_key key;
550
551 root = device->dev_root->fs_info->chunk_root;
552
553 path = btrfs_alloc_path();
554 if (!path)
555 return -ENOMEM;
556
557 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
558 key.type = BTRFS_DEV_ITEM_KEY;
559 key.offset = device->devid;
560
561 ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
562 if (ret < 0)
563 goto out;
564
565 if (ret > 0) {
566 ret = -ENOENT;
567 goto out;
568 }
569
570 leaf = path->nodes[0];
571 dev_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dev_item);
572
573 btrfs_set_device_id(leaf, dev_item, device->devid);
574 btrfs_set_device_type(leaf, dev_item, device->type);
575 btrfs_set_device_io_align(leaf, dev_item, device->io_align);
576 btrfs_set_device_io_width(leaf, dev_item, device->io_width);
577 btrfs_set_device_sector_size(leaf, dev_item, device->sector_size);
578 btrfs_set_device_total_bytes(leaf, dev_item, device->total_bytes);
579 btrfs_set_device_bytes_used(leaf, dev_item, device->bytes_used);
580 btrfs_mark_buffer_dirty(leaf);
581
582 out:
583 btrfs_free_path(path);
584 return ret;
585 }
586
587 int btrfs_add_system_chunk(struct btrfs_trans_handle *trans,
588 struct btrfs_root *root,
589 struct btrfs_key *key,
590 struct btrfs_chunk *chunk, int item_size)
591 {
592 struct btrfs_super_block *super_copy = &root->fs_info->super_copy;
593 struct btrfs_disk_key disk_key;
594 u32 array_size;
595 u8 *ptr;
596
597 array_size = btrfs_super_sys_array_size(super_copy);
598 if (array_size + item_size > BTRFS_SYSTEM_CHUNK_ARRAY_SIZE)
599 return -EFBIG;
600
601 ptr = super_copy->sys_chunk_array + array_size;
602 btrfs_cpu_key_to_disk(&disk_key, key);
603 memcpy(ptr, &disk_key, sizeof(disk_key));
604 ptr += sizeof(disk_key);
605 memcpy(ptr, chunk, item_size);
606 item_size += sizeof(disk_key);
607 btrfs_set_super_sys_array_size(super_copy, array_size + item_size);
608 return 0;
609 }
610
611 static u64 div_factor(u64 num, int factor)
612 {
613 if (factor == 10)
614 return num;
615 num *= factor;
616 return num / 10;
617 }
618
619 static u64 chunk_bytes_by_type(u64 type, u64 calc_size, int num_stripes,
620 int sub_stripes)
621 {
622 if (type & (BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_DUP))
623 return calc_size;
624 else if (type & BTRFS_BLOCK_GROUP_RAID10)
625 return calc_size * (num_stripes / sub_stripes);
626 else
627 return calc_size * num_stripes;
628 }
629
630
631 int btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
632 struct btrfs_root *extent_root, u64 *start,
633 u64 *num_bytes, u64 type)
634 {
635 u64 dev_offset;
636 struct btrfs_fs_info *info = extent_root->fs_info;
637 struct btrfs_root *chunk_root = extent_root->fs_info->chunk_root;
638 struct btrfs_stripe *stripes;
639 struct btrfs_device *device = NULL;
640 struct btrfs_chunk *chunk;
641 struct list_head private_devs;
642 struct list_head *dev_list = &extent_root->fs_info->fs_devices->devices;
643 struct list_head *cur;
644 struct map_lookup *map;
645 int min_stripe_size = 1 * 1024 * 1024;
646 u64 calc_size = 8 * 1024 * 1024;
647 u64 min_free;
648 u64 max_chunk_size = 4 * calc_size;
649 u64 avail;
650 u64 max_avail = 0;
651 u64 percent_max;
652 int num_stripes = 1;
653 int min_stripes = 1;
654 int sub_stripes = 0;
655 int looped = 0;
656 int ret;
657 int index;
658 int stripe_len = 64 * 1024;
659 struct btrfs_key key;
660
661 if (list_empty(dev_list)) {
662 return -ENOSPC;
663 }
664
665 if (type & (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID1 |
666 BTRFS_BLOCK_GROUP_RAID10 |
667 BTRFS_BLOCK_GROUP_DUP)) {
668 if (type & BTRFS_BLOCK_GROUP_SYSTEM) {
669 calc_size = 8 * 1024 * 1024;
670 max_chunk_size = calc_size * 2;
671 min_stripe_size = 1 * 1024 * 1024;
672 } else if (type & BTRFS_BLOCK_GROUP_DATA) {
673 calc_size = 1024 * 1024 * 1024;
674 max_chunk_size = 10 * calc_size;
675 min_stripe_size = 64 * 1024 * 1024;
676 } else if (type & BTRFS_BLOCK_GROUP_METADATA) {
677 calc_size = 1024 * 1024 * 1024;
678 max_chunk_size = 4 * calc_size;
679 min_stripe_size = 32 * 1024 * 1024;
680 }
681 }
682 if (type & BTRFS_BLOCK_GROUP_RAID1) {
683 num_stripes = min_t(u64, 2,
684 btrfs_super_num_devices(&info->super_copy));
685 if (num_stripes < 2)
686 return -ENOSPC;
687 min_stripes = 2;
688 }
689 if (type & BTRFS_BLOCK_GROUP_DUP) {
690 num_stripes = 2;
691 min_stripes = 2;
692 }
693 if (type & (BTRFS_BLOCK_GROUP_RAID0)) {
694 num_stripes = btrfs_super_num_devices(&info->super_copy);
695 min_stripes = 2;
696 }
697 if (type & (BTRFS_BLOCK_GROUP_RAID10)) {
698 num_stripes = btrfs_super_num_devices(&info->super_copy);
699 if (num_stripes < 4)
700 return -ENOSPC;
701 num_stripes &= ~(u32)1;
702 sub_stripes = 2;
703 min_stripes = 4;
704 }
705
706 /* we don't want a chunk larger than 10% of the FS */
707 percent_max = div_factor(btrfs_super_total_bytes(&info->super_copy), 1);
708 max_chunk_size = min(percent_max, max_chunk_size);
709
710 again:
711 if (chunk_bytes_by_type(type, calc_size, num_stripes, sub_stripes) >
712 max_chunk_size) {
713 calc_size = max_chunk_size;
714 calc_size /= num_stripes;
715 calc_size /= stripe_len;
716 calc_size *= stripe_len;
717 }
718 /* we don't want tiny stripes */
719 calc_size = max_t(u64, calc_size, min_stripe_size);
720
721 calc_size /= stripe_len;
722 calc_size *= stripe_len;
723 INIT_LIST_HEAD(&private_devs);
724 cur = dev_list->next;
725 index = 0;
726
727 if (type & BTRFS_BLOCK_GROUP_DUP)
728 min_free = calc_size * 2;
729 else
730 min_free = calc_size;
731
732 /* build a private list of devices we will allocate from */
733 while(index < num_stripes) {
734 device = list_entry(cur, struct btrfs_device, dev_list);
735 avail = device->total_bytes - device->bytes_used;
736 cur = cur->next;
737 if (avail >= min_free) {
738 list_move_tail(&device->dev_list, &private_devs);
739 index++;
740 if (type & BTRFS_BLOCK_GROUP_DUP)
741 index++;
742 } else if (avail > max_avail)
743 max_avail = avail;
744 if (cur == dev_list)
745 break;
746 }
747 if (index < num_stripes) {
748 list_splice(&private_devs, dev_list);
749 if (index >= min_stripes) {
750 num_stripes = index;
751 if (type & (BTRFS_BLOCK_GROUP_RAID10)) {
752 num_stripes /= sub_stripes;
753 num_stripes *= sub_stripes;
754 }
755 looped = 1;
756 goto again;
757 }
758 if (!looped && max_avail > 0) {
759 looped = 1;
760 calc_size = max_avail;
761 goto again;
762 }
763 return -ENOSPC;
764 }
765 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
766 key.type = BTRFS_CHUNK_ITEM_KEY;
767 ret = find_next_chunk(chunk_root, BTRFS_FIRST_CHUNK_TREE_OBJECTID,
768 &key.offset);
769 if (ret)
770 return ret;
771
772 chunk = kmalloc(btrfs_chunk_item_size(num_stripes), GFP_NOFS);
773 if (!chunk)
774 return -ENOMEM;
775
776 map = kmalloc(map_lookup_size(num_stripes), GFP_NOFS);
777 if (!map) {
778 kfree(chunk);
779 return -ENOMEM;
780 }
781
782 stripes = &chunk->stripe;
783 *num_bytes = chunk_bytes_by_type(type, calc_size,
784 num_stripes, sub_stripes);
785 index = 0;
786 while(index < num_stripes) {
787 struct btrfs_stripe *stripe;
788 BUG_ON(list_empty(&private_devs));
789 cur = private_devs.next;
790 device = list_entry(cur, struct btrfs_device, dev_list);
791
792 /* loop over this device again if we're doing a dup group */
793 if (!(type & BTRFS_BLOCK_GROUP_DUP) ||
794 (index == num_stripes - 1))
795 list_move_tail(&device->dev_list, dev_list);
796
797 ret = btrfs_alloc_dev_extent(trans, device,
798 info->chunk_root->root_key.objectid,
799 BTRFS_FIRST_CHUNK_TREE_OBJECTID, key.offset,
800 calc_size, &dev_offset);
801 BUG_ON(ret);
802
803 device->bytes_used += calc_size;
804 ret = btrfs_update_device(trans, device);
805 BUG_ON(ret);
806
807 map->stripes[index].dev = device;
808 map->stripes[index].physical = dev_offset;
809 stripe = stripes + index;
810 btrfs_set_stack_stripe_devid(stripe, device->devid);
811 btrfs_set_stack_stripe_offset(stripe, dev_offset);
812 memcpy(stripe->dev_uuid, device->uuid, BTRFS_UUID_SIZE);
813 index++;
814 }
815 BUG_ON(!list_empty(&private_devs));
816
817 /* key was set above */
818 btrfs_set_stack_chunk_length(chunk, *num_bytes);
819 btrfs_set_stack_chunk_owner(chunk, extent_root->root_key.objectid);
820 btrfs_set_stack_chunk_stripe_len(chunk, stripe_len);
821 btrfs_set_stack_chunk_type(chunk, type);
822 btrfs_set_stack_chunk_num_stripes(chunk, num_stripes);
823 btrfs_set_stack_chunk_io_align(chunk, stripe_len);
824 btrfs_set_stack_chunk_io_width(chunk, stripe_len);
825 btrfs_set_stack_chunk_sector_size(chunk, extent_root->sectorsize);
826 btrfs_set_stack_chunk_sub_stripes(chunk, sub_stripes);
827 map->sector_size = extent_root->sectorsize;
828 map->stripe_len = stripe_len;
829 map->io_align = stripe_len;
830 map->io_width = stripe_len;
831 map->type = type;
832 map->num_stripes = num_stripes;
833 map->sub_stripes = sub_stripes;
834
835 ret = btrfs_insert_item(trans, chunk_root, &key, chunk,
836 btrfs_chunk_item_size(num_stripes));
837 BUG_ON(ret);
838 *start = key.offset;;
839
840 map->ce.start = key.offset;
841 map->ce.size = *num_bytes;
842
843 ret = insert_existing_cache_extent(
844 &extent_root->fs_info->mapping_tree.cache_tree,
845 &map->ce);
846 BUG_ON(ret);
847
848 if (type & BTRFS_BLOCK_GROUP_SYSTEM) {
849 ret = btrfs_add_system_chunk(trans, chunk_root, &key,
850 chunk, btrfs_chunk_item_size(num_stripes));
851 BUG_ON(ret);
852 }
853
854 kfree(chunk);
855 return ret;
856 }
857
858 int btrfs_alloc_data_chunk(struct btrfs_trans_handle *trans,
859 struct btrfs_root *extent_root, u64 *start,
860 u64 num_bytes, u64 type)
861 {
862 u64 dev_offset;
863 struct btrfs_fs_info *info = extent_root->fs_info;
864 struct btrfs_root *chunk_root = extent_root->fs_info->chunk_root;
865 struct btrfs_stripe *stripes;
866 struct btrfs_device *device = NULL;
867 struct btrfs_chunk *chunk;
868 struct list_head *dev_list = &extent_root->fs_info->fs_devices->devices;
869 struct list_head *cur;
870 struct map_lookup *map;
871 u64 calc_size = 8 * 1024 * 1024;
872 int num_stripes = 1;
873 int sub_stripes = 0;
874 int ret;
875 int index;
876 int stripe_len = 64 * 1024;
877 struct btrfs_key key;
878
879 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
880 key.type = BTRFS_CHUNK_ITEM_KEY;
881 ret = find_next_chunk(chunk_root, BTRFS_FIRST_CHUNK_TREE_OBJECTID,
882 &key.offset);
883 if (ret)
884 return ret;
885
886 chunk = kmalloc(btrfs_chunk_item_size(num_stripes), GFP_NOFS);
887 if (!chunk)
888 return -ENOMEM;
889
890 map = kmalloc(map_lookup_size(num_stripes), GFP_NOFS);
891 if (!map) {
892 kfree(chunk);
893 return -ENOMEM;
894 }
895
896 stripes = &chunk->stripe;
897 calc_size = num_bytes;
898
899 index = 0;
900 cur = dev_list->next;
901 device = list_entry(cur, struct btrfs_device, dev_list);
902
903 while (index < num_stripes) {
904 struct btrfs_stripe *stripe;
905
906 ret = btrfs_alloc_dev_extent(trans, device,
907 info->chunk_root->root_key.objectid,
908 BTRFS_FIRST_CHUNK_TREE_OBJECTID, key.offset,
909 calc_size, &dev_offset);
910 BUG_ON(ret);
911
912 device->bytes_used += calc_size;
913 ret = btrfs_update_device(trans, device);
914 BUG_ON(ret);
915
916 map->stripes[index].dev = device;
917 map->stripes[index].physical = dev_offset;
918 stripe = stripes + index;
919 btrfs_set_stack_stripe_devid(stripe, device->devid);
920 btrfs_set_stack_stripe_offset(stripe, dev_offset);
921 memcpy(stripe->dev_uuid, device->uuid, BTRFS_UUID_SIZE);
922 index++;
923 }
924
925 /* key was set above */
926 btrfs_set_stack_chunk_length(chunk, num_bytes);
927 btrfs_set_stack_chunk_owner(chunk, extent_root->root_key.objectid);
928 btrfs_set_stack_chunk_stripe_len(chunk, stripe_len);
929 btrfs_set_stack_chunk_type(chunk, type);
930 btrfs_set_stack_chunk_num_stripes(chunk, num_stripes);
931 btrfs_set_stack_chunk_io_align(chunk, stripe_len);
932 btrfs_set_stack_chunk_io_width(chunk, stripe_len);
933 btrfs_set_stack_chunk_sector_size(chunk, extent_root->sectorsize);
934 btrfs_set_stack_chunk_sub_stripes(chunk, sub_stripes);
935 map->sector_size = extent_root->sectorsize;
936 map->stripe_len = stripe_len;
937 map->io_align = stripe_len;
938 map->io_width = stripe_len;
939 map->type = type;
940 map->num_stripes = num_stripes;
941 map->sub_stripes = sub_stripes;
942
943 ret = btrfs_insert_item(trans, chunk_root, &key, chunk,
944 btrfs_chunk_item_size(num_stripes));
945 BUG_ON(ret);
946 *start = key.offset;
947
948 map->ce.start = key.offset;
949 map->ce.size = num_bytes;
950
951 ret = insert_existing_cache_extent(
952 &extent_root->fs_info->mapping_tree.cache_tree,
953 &map->ce);
954 BUG_ON(ret);
955
956 kfree(chunk);
957 return ret;
958 }
959
960 void btrfs_mapping_init(struct btrfs_mapping_tree *tree)
961 {
962 cache_tree_init(&tree->cache_tree);
963 }
964
965 int btrfs_num_copies(struct btrfs_mapping_tree *map_tree, u64 logical, u64 len)
966 {
967 struct cache_extent *ce;
968 struct map_lookup *map;
969 int ret;
970
971 ce = find_first_cache_extent(&map_tree->cache_tree, logical);
972 BUG_ON(!ce);
973 BUG_ON(ce->start > logical || ce->start + ce->size < logical);
974 map = container_of(ce, struct map_lookup, ce);
975
976 if (map->type & (BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID1))
977 ret = map->num_stripes;
978 else if (map->type & BTRFS_BLOCK_GROUP_RAID10)
979 ret = map->sub_stripes;
980 else
981 ret = 1;
982 return ret;
983 }
984
985 int btrfs_rmap_block(struct btrfs_mapping_tree *map_tree,
986 u64 chunk_start, u64 physical, u64 devid,
987 u64 **logical, int *naddrs, int *stripe_len)
988 {
989 struct cache_extent *ce;
990 struct map_lookup *map;
991 u64 *buf;
992 u64 bytenr;
993 u64 length;
994 u64 stripe_nr;
995 int i, j, nr = 0;
996
997 ce = find_first_cache_extent(&map_tree->cache_tree, chunk_start);
998 BUG_ON(!ce);
999 map = container_of(ce, struct map_lookup, ce);
1000
1001 length = ce->size;
1002 if (map->type & BTRFS_BLOCK_GROUP_RAID10)
1003 length = ce->size / (map->num_stripes / map->sub_stripes);
1004 else if (map->type & BTRFS_BLOCK_GROUP_RAID0)
1005 length = ce->size / map->num_stripes;
1006
1007 buf = kzalloc(sizeof(u64) * map->num_stripes, GFP_NOFS);
1008
1009 for (i = 0; i < map->num_stripes; i++) {
1010 if (devid && map->stripes[i].dev->devid != devid)
1011 continue;
1012 if (map->stripes[i].physical > physical ||
1013 map->stripes[i].physical + length <= physical)
1014 continue;
1015
1016 stripe_nr = (physical - map->stripes[i].physical) /
1017 map->stripe_len;
1018
1019 if (map->type & BTRFS_BLOCK_GROUP_RAID10) {
1020 stripe_nr = (stripe_nr * map->num_stripes + i) /
1021 map->sub_stripes;
1022 } else if (map->type & BTRFS_BLOCK_GROUP_RAID0) {
1023 stripe_nr = stripe_nr * map->num_stripes + i;
1024 }
1025 bytenr = ce->start + stripe_nr * map->stripe_len;
1026 for (j = 0; j < nr; j++) {
1027 if (buf[j] == bytenr)
1028 break;
1029 }
1030 if (j == nr)
1031 buf[nr++] = bytenr;
1032 }
1033
1034 *logical = buf;
1035 *naddrs = nr;
1036 *stripe_len = map->stripe_len;
1037
1038 return 0;
1039 }
1040
1041 int btrfs_map_block(struct btrfs_mapping_tree *map_tree, int rw,
1042 u64 logical, u64 *length,
1043 struct btrfs_multi_bio **multi_ret, int mirror_num)
1044 {
1045 struct cache_extent *ce;
1046 struct map_lookup *map;
1047 u64 offset;
1048 u64 stripe_offset;
1049 u64 stripe_nr;
1050 int stripes_allocated = 8;
1051 int stripes_required = 1;
1052 int stripe_index;
1053 int i;
1054 struct btrfs_multi_bio *multi = NULL;
1055
1056 if (multi_ret && rw == READ) {
1057 stripes_allocated = 1;
1058 }
1059 again:
1060 if (multi_ret) {
1061 multi = kzalloc(btrfs_multi_bio_size(stripes_allocated),
1062 GFP_NOFS);
1063 if (!multi)
1064 return -ENOMEM;
1065 }
1066
1067 ce = find_first_cache_extent(&map_tree->cache_tree, logical);
1068 BUG_ON(!ce);
1069 BUG_ON(ce->start > logical || ce->start + ce->size < logical);
1070 map = container_of(ce, struct map_lookup, ce);
1071 offset = logical - ce->start;
1072
1073 if (rw == WRITE) {
1074 if (map->type & (BTRFS_BLOCK_GROUP_RAID1 |
1075 BTRFS_BLOCK_GROUP_DUP)) {
1076 stripes_required = map->num_stripes;
1077 } else if (map->type & BTRFS_BLOCK_GROUP_RAID10) {
1078 stripes_required = map->sub_stripes;
1079 }
1080 }
1081 /* if our multi bio struct is too small, back off and try again */
1082 if (multi_ret && rw == WRITE &&
1083 stripes_allocated < stripes_required) {
1084 stripes_allocated = map->num_stripes;
1085 kfree(multi);
1086 goto again;
1087 }
1088 stripe_nr = offset;
1089 /*
1090 * stripe_nr counts the total number of stripes we have to stride
1091 * to get to this block
1092 */
1093 stripe_nr = stripe_nr / map->stripe_len;
1094
1095 stripe_offset = stripe_nr * map->stripe_len;
1096 BUG_ON(offset < stripe_offset);
1097
1098 /* stripe_offset is the offset of this block in its stripe*/
1099 stripe_offset = offset - stripe_offset;
1100
1101 if (map->type & (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID1 |
1102 BTRFS_BLOCK_GROUP_RAID10 |
1103 BTRFS_BLOCK_GROUP_DUP)) {
1104 /* we limit the length of each bio to what fits in a stripe */
1105 *length = min_t(u64, ce->size - offset,
1106 map->stripe_len - stripe_offset);
1107 } else {
1108 *length = ce->size - offset;
1109 }
1110
1111 if (!multi_ret)
1112 goto out;
1113
1114 multi->num_stripes = 1;
1115 stripe_index = 0;
1116 if (map->type & BTRFS_BLOCK_GROUP_RAID1) {
1117 if (rw == WRITE)
1118 multi->num_stripes = map->num_stripes;
1119 else if (mirror_num)
1120 stripe_index = mirror_num - 1;
1121 else
1122 stripe_index = stripe_nr % map->num_stripes;
1123 } else if (map->type & BTRFS_BLOCK_GROUP_RAID10) {
1124 int factor = map->num_stripes / map->sub_stripes;
1125
1126 stripe_index = stripe_nr % factor;
1127 stripe_index *= map->sub_stripes;
1128
1129 if (rw == WRITE)
1130 multi->num_stripes = map->sub_stripes;
1131 else if (mirror_num)
1132 stripe_index += mirror_num - 1;
1133 else
1134 stripe_index = stripe_nr % map->sub_stripes;
1135
1136 stripe_nr = stripe_nr / factor;
1137 } else if (map->type & BTRFS_BLOCK_GROUP_DUP) {
1138 if (rw == WRITE)
1139 multi->num_stripes = map->num_stripes;
1140 else if (mirror_num)
1141 stripe_index = mirror_num - 1;
1142 } else {
1143 /*
1144 * after this do_div call, stripe_nr is the number of stripes
1145 * on this device we have to walk to find the data, and
1146 * stripe_index is the number of our device in the stripe array
1147 */
1148 stripe_index = stripe_nr % map->num_stripes;
1149 stripe_nr = stripe_nr / map->num_stripes;
1150 }
1151 BUG_ON(stripe_index >= map->num_stripes);
1152
1153 for (i = 0; i < multi->num_stripes; i++) {
1154 multi->stripes[i].physical =
1155 map->stripes[stripe_index].physical + stripe_offset +
1156 stripe_nr * map->stripe_len;
1157 multi->stripes[i].dev = map->stripes[stripe_index].dev;
1158 stripe_index++;
1159 }
1160 *multi_ret = multi;
1161 out:
1162 return 0;
1163 }
1164
1165 struct btrfs_device *btrfs_find_device(struct btrfs_root *root, u64 devid,
1166 u8 *uuid, u8 *fsid)
1167 {
1168 struct btrfs_device *device;
1169 struct btrfs_fs_devices *cur_devices;
1170
1171 cur_devices = root->fs_info->fs_devices;
1172 while (cur_devices) {
1173 if (!fsid ||
1174 !memcmp(cur_devices->fsid, fsid, BTRFS_UUID_SIZE)) {
1175 device = __find_device(&cur_devices->devices,
1176 devid, uuid);
1177 if (device)
1178 return device;
1179 }
1180 cur_devices = cur_devices->seed;
1181 }
1182 return NULL;
1183 }
1184
1185 int btrfs_bootstrap_super_map(struct btrfs_mapping_tree *map_tree,
1186 struct btrfs_fs_devices *fs_devices)
1187 {
1188 struct map_lookup *map;
1189 u64 logical = BTRFS_SUPER_INFO_OFFSET;
1190 u64 length = BTRFS_SUPER_INFO_SIZE;
1191 int num_stripes = 0;
1192 int sub_stripes = 0;
1193 int ret;
1194 int i;
1195 struct list_head *cur;
1196
1197 list_for_each(cur, &fs_devices->devices) {
1198 num_stripes++;
1199 }
1200 map = kmalloc(map_lookup_size(num_stripes), GFP_NOFS);
1201 if (!map)
1202 return -ENOMEM;
1203
1204 map->ce.start = logical;
1205 map->ce.size = length;
1206 map->num_stripes = num_stripes;
1207 map->sub_stripes = sub_stripes;
1208 map->io_width = length;
1209 map->io_align = length;
1210 map->sector_size = length;
1211 map->stripe_len = length;
1212 map->type = BTRFS_BLOCK_GROUP_RAID1;
1213
1214 i = 0;
1215 list_for_each(cur, &fs_devices->devices) {
1216 struct btrfs_device *device = list_entry(cur,
1217 struct btrfs_device,
1218 dev_list);
1219 map->stripes[i].physical = logical;
1220 map->stripes[i].dev = device;
1221 i++;
1222 }
1223 ret = insert_existing_cache_extent(&map_tree->cache_tree, &map->ce);
1224 if (ret == -EEXIST) {
1225 struct cache_extent *old;
1226 struct map_lookup *old_map;
1227 old = find_cache_extent(&map_tree->cache_tree, logical, length);
1228 old_map = container_of(old, struct map_lookup, ce);
1229 remove_cache_extent(&map_tree->cache_tree, old);
1230 kfree(old_map);
1231 ret = insert_existing_cache_extent(&map_tree->cache_tree,
1232 &map->ce);
1233 }
1234 BUG_ON(ret);
1235 return 0;
1236 }
1237
1238 int btrfs_chunk_readonly(struct btrfs_root *root, u64 chunk_offset)
1239 {
1240 struct cache_extent *ce;
1241 struct map_lookup *map;
1242 struct btrfs_mapping_tree *map_tree = &root->fs_info->mapping_tree;
1243 int readonly = 0;
1244 int i;
1245
1246 ce = find_first_cache_extent(&map_tree->cache_tree, chunk_offset);
1247 BUG_ON(!ce);
1248
1249 map = container_of(ce, struct map_lookup, ce);
1250 for (i = 0; i < map->num_stripes; i++) {
1251 if (!map->stripes[i].dev->writeable) {
1252 readonly = 1;
1253 break;
1254 }
1255 }
1256
1257 return readonly;
1258 }
1259
1260 static struct btrfs_device *fill_missing_device(u64 devid)
1261 {
1262 struct btrfs_device *device;
1263
1264 device = kzalloc(sizeof(*device), GFP_NOFS);
1265 device->devid = devid;
1266 device->fd = -1;
1267 return device;
1268 }
1269
1270 static int read_one_chunk(struct btrfs_root *root, struct btrfs_key *key,
1271 struct extent_buffer *leaf,
1272 struct btrfs_chunk *chunk)
1273 {
1274 struct btrfs_mapping_tree *map_tree = &root->fs_info->mapping_tree;
1275 struct map_lookup *map;
1276 struct cache_extent *ce;
1277 u64 logical;
1278 u64 length;
1279 u64 devid;
1280 u8 uuid[BTRFS_UUID_SIZE];
1281 int num_stripes;
1282 int ret;
1283 int i;
1284
1285 logical = key->offset;
1286 length = btrfs_chunk_length(leaf, chunk);
1287
1288 ce = find_first_cache_extent(&map_tree->cache_tree, logical);
1289
1290 /* already mapped? */
1291 if (ce && ce->start <= logical && ce->start + ce->size > logical) {
1292 return 0;
1293 }
1294
1295 num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
1296 map = kmalloc(map_lookup_size(num_stripes), GFP_NOFS);
1297 if (!map)
1298 return -ENOMEM;
1299
1300 map->ce.start = logical;
1301 map->ce.size = length;
1302 map->num_stripes = num_stripes;
1303 map->io_width = btrfs_chunk_io_width(leaf, chunk);
1304 map->io_align = btrfs_chunk_io_align(leaf, chunk);
1305 map->sector_size = btrfs_chunk_sector_size(leaf, chunk);
1306 map->stripe_len = btrfs_chunk_stripe_len(leaf, chunk);
1307 map->type = btrfs_chunk_type(leaf, chunk);
1308 map->sub_stripes = btrfs_chunk_sub_stripes(leaf, chunk);
1309
1310 for (i = 0; i < num_stripes; i++) {
1311 map->stripes[i].physical =
1312 btrfs_stripe_offset_nr(leaf, chunk, i);
1313 devid = btrfs_stripe_devid_nr(leaf, chunk, i);
1314 read_extent_buffer(leaf, uuid, (unsigned long)
1315 btrfs_stripe_dev_uuid_nr(chunk, i),
1316 BTRFS_UUID_SIZE);
1317 map->stripes[i].dev = btrfs_find_device(root, devid, uuid,
1318 NULL);
1319 if (!map->stripes[i].dev) {
1320 map->stripes[i].dev = fill_missing_device(devid);
1321 printf("warning, device %llu is missing\n",
1322 (unsigned long long)devid);
1323 }
1324
1325 }
1326 ret = insert_existing_cache_extent(&map_tree->cache_tree, &map->ce);
1327 BUG_ON(ret);
1328
1329 return 0;
1330 }
1331
1332 static int fill_device_from_item(struct extent_buffer *leaf,
1333 struct btrfs_dev_item *dev_item,
1334 struct btrfs_device *device)
1335 {
1336 unsigned long ptr;
1337
1338 device->devid = btrfs_device_id(leaf, dev_item);
1339 device->total_bytes = btrfs_device_total_bytes(leaf, dev_item);
1340 device->bytes_used = btrfs_device_bytes_used(leaf, dev_item);
1341 device->type = btrfs_device_type(leaf, dev_item);
1342 device->io_align = btrfs_device_io_align(leaf, dev_item);
1343 device->io_width = btrfs_device_io_width(leaf, dev_item);
1344 device->sector_size = btrfs_device_sector_size(leaf, dev_item);
1345
1346 ptr = (unsigned long)btrfs_device_uuid(dev_item);
1347 read_extent_buffer(leaf, device->uuid, ptr, BTRFS_UUID_SIZE);
1348
1349 return 0;
1350 }
1351
1352 static int open_seed_devices(struct btrfs_root *root, u8 *fsid)
1353 {
1354 struct btrfs_fs_devices *fs_devices;
1355 int ret;
1356
1357 fs_devices = root->fs_info->fs_devices->seed;
1358 while (fs_devices) {
1359 if (!memcmp(fs_devices->fsid, fsid, BTRFS_UUID_SIZE)) {
1360 ret = 0;
1361 goto out;
1362 }
1363 fs_devices = fs_devices->seed;
1364 }
1365
1366 fs_devices = find_fsid(fsid);
1367 if (!fs_devices) {
1368 ret = -ENOENT;
1369 goto out;
1370 }
1371
1372 ret = btrfs_open_devices(fs_devices, O_RDONLY);
1373 if (ret)
1374 goto out;
1375
1376 fs_devices->seed = root->fs_info->fs_devices->seed;
1377 root->fs_info->fs_devices->seed = fs_devices;
1378 out:
1379 return ret;
1380 }
1381
1382 static int read_one_dev(struct btrfs_root *root,
1383 struct extent_buffer *leaf,
1384 struct btrfs_dev_item *dev_item)
1385 {
1386 struct btrfs_device *device;
1387 u64 devid;
1388 int ret = 0;
1389 u8 fs_uuid[BTRFS_UUID_SIZE];
1390 u8 dev_uuid[BTRFS_UUID_SIZE];
1391
1392 devid = btrfs_device_id(leaf, dev_item);
1393 read_extent_buffer(leaf, dev_uuid,
1394 (unsigned long)btrfs_device_uuid(dev_item),
1395 BTRFS_UUID_SIZE);
1396 read_extent_buffer(leaf, fs_uuid,
1397 (unsigned long)btrfs_device_fsid(dev_item),
1398 BTRFS_UUID_SIZE);
1399
1400 if (memcmp(fs_uuid, root->fs_info->fsid, BTRFS_UUID_SIZE)) {
1401 ret = open_seed_devices(root, fs_uuid);
1402 if (ret)
1403 return ret;
1404 }
1405
1406 device = btrfs_find_device(root, devid, dev_uuid, fs_uuid);
1407 if (!device) {
1408 printk("warning devid %llu not found already\n",
1409 (unsigned long long)devid);
1410 device = kmalloc(sizeof(*device), GFP_NOFS);
1411 if (!device)
1412 return -ENOMEM;
1413 device->total_ios = 0;
1414 list_add(&device->dev_list,
1415 &root->fs_info->fs_devices->devices);
1416 }
1417
1418 fill_device_from_item(leaf, dev_item, device);
1419 device->dev_root = root->fs_info->dev_root;
1420 return ret;
1421 }
1422
1423 int btrfs_read_super_device(struct btrfs_root *root, struct extent_buffer *buf)
1424 {
1425 struct btrfs_dev_item *dev_item;
1426
1427 dev_item = (struct btrfs_dev_item *)offsetof(struct btrfs_super_block,
1428 dev_item);
1429 return read_one_dev(root, buf, dev_item);
1430 }
1431
1432 int btrfs_read_sys_array(struct btrfs_root *root)
1433 {
1434 struct btrfs_super_block *super_copy = &root->fs_info->super_copy;
1435 struct extent_buffer *sb;
1436 struct btrfs_disk_key *disk_key;
1437 struct btrfs_chunk *chunk;
1438 struct btrfs_key key;
1439 u32 num_stripes;
1440 u32 array_size;
1441 u32 len = 0;
1442 u8 *ptr;
1443 unsigned long sb_ptr;
1444 u32 cur;
1445 int ret;
1446
1447 sb = btrfs_find_create_tree_block(root, BTRFS_SUPER_INFO_OFFSET,
1448 BTRFS_SUPER_INFO_SIZE);
1449 if (!sb)
1450 return -ENOMEM;
1451 btrfs_set_buffer_uptodate(sb);
1452 write_extent_buffer(sb, super_copy, 0, BTRFS_SUPER_INFO_SIZE);
1453 array_size = btrfs_super_sys_array_size(super_copy);
1454
1455 /*
1456 * we do this loop twice, once for the device items and
1457 * once for all of the chunks. This way there are device
1458 * structs filled in for every chunk
1459 */
1460 ptr = super_copy->sys_chunk_array;
1461 sb_ptr = offsetof(struct btrfs_super_block, sys_chunk_array);
1462 cur = 0;
1463
1464 while (cur < array_size) {
1465 disk_key = (struct btrfs_disk_key *)ptr;
1466 btrfs_disk_key_to_cpu(&key, disk_key);
1467
1468 len = sizeof(*disk_key);
1469 ptr += len;
1470 sb_ptr += len;
1471 cur += len;
1472
1473 if (key.type == BTRFS_CHUNK_ITEM_KEY) {
1474 chunk = (struct btrfs_chunk *)sb_ptr;
1475 ret = read_one_chunk(root, &key, sb, chunk);
1476 BUG_ON(ret);
1477 num_stripes = btrfs_chunk_num_stripes(sb, chunk);
1478 len = btrfs_chunk_item_size(num_stripes);
1479 } else {
1480 BUG();
1481 }
1482 ptr += len;
1483 sb_ptr += len;
1484 cur += len;
1485 }
1486 free_extent_buffer(sb);
1487 return 0;
1488 }
1489
1490 int btrfs_read_chunk_tree(struct btrfs_root *root)
1491 {
1492 struct btrfs_path *path;
1493 struct extent_buffer *leaf;
1494 struct btrfs_key key;
1495 struct btrfs_key found_key;
1496 int ret;
1497 int slot;
1498
1499 root = root->fs_info->chunk_root;
1500
1501 path = btrfs_alloc_path();
1502 if (!path)
1503 return -ENOMEM;
1504
1505 /* first we search for all of the device items, and then we
1506 * read in all of the chunk items. This way we can create chunk
1507 * mappings that reference all of the devices that are afound
1508 */
1509 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
1510 key.offset = 0;
1511 key.type = 0;
1512 again:
1513 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1514 while(1) {
1515 leaf = path->nodes[0];
1516 slot = path->slots[0];
1517 if (slot >= btrfs_header_nritems(leaf)) {
1518 ret = btrfs_next_leaf(root, path);
1519 if (ret == 0)
1520 continue;
1521 if (ret < 0)
1522 goto error;
1523 break;
1524 }
1525 btrfs_item_key_to_cpu(leaf, &found_key, slot);
1526 if (key.objectid == BTRFS_DEV_ITEMS_OBJECTID) {
1527 if (found_key.objectid != BTRFS_DEV_ITEMS_OBJECTID)
1528 break;
1529 if (found_key.type == BTRFS_DEV_ITEM_KEY) {
1530 struct btrfs_dev_item *dev_item;
1531 dev_item = btrfs_item_ptr(leaf, slot,
1532 struct btrfs_dev_item);
1533 ret = read_one_dev(root, leaf, dev_item);
1534 BUG_ON(ret);
1535 }
1536 } else if (found_key.type == BTRFS_CHUNK_ITEM_KEY) {
1537 struct btrfs_chunk *chunk;
1538 chunk = btrfs_item_ptr(leaf, slot, struct btrfs_chunk);
1539 ret = read_one_chunk(root, &found_key, leaf, chunk);
1540 BUG_ON(ret);
1541 }
1542 path->slots[0]++;
1543 }
1544 if (key.objectid == BTRFS_DEV_ITEMS_OBJECTID) {
1545 key.objectid = 0;
1546 btrfs_release_path(root, path);
1547 goto again;
1548 }
1549
1550 btrfs_free_path(path);
1551 ret = 0;
1552 error:
1553 return ret;
1554 }
1555
1556 struct list_head *btrfs_scanned_uuids(void)
1557 {
1558 return &fs_uuids;
1559 }
(deprecated) Btrfs progs developments and patch integration