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Btrfs: add disk ioctl, mostly working
[linux-2.6-block.git] / fs / btrfs / disk-io.c
CommitLineData
e20d96d6
CM		 1#include <linux/module.h>
2#include <linux/fs.h>
d98237b3 3#include <linux/blkdev.h>
87cbda5c
CM		 4#include <linux/crypto.h>
5#include <linux/scatterlist.h>
22b0ebda 6#include <linux/swap.h>
0f7d52f4 7#include <linux/radix-tree.h>
eb60ceac
CM		 8#include "ctree.h"
9#include "disk-io.h"
e089f05c 10#include "transaction.h"
0f7d52f4 11#include "btrfs_inode.h"
eb60ceac 12
7eccb903
CM		 13struct dev_lookup {
14 u64 block_start;
15 u64 num_blocks;
16 struct block_device *bdev;
17};
18
8352d8a4
CM		 19int btrfs_insert_dev_radix(struct btrfs_root *root,
20 struct block_device *bdev,
21 u64 block_start,
22 u64 num_blocks)
23{
24 struct dev_lookup *lookup;
25 char b[BDEVNAME_SIZE];
26 int ret;
27
28 lookup = kmalloc(sizeof(*lookup), GFP_NOFS);
29 if (!lookup)
30 return -ENOMEM;
31 lookup->block_start = block_start;
32 lookup->num_blocks = num_blocks;
33 lookup->bdev = bdev;
34printk("inserting %s into dev radix %Lu %Lu\n", bdevname(bdev, b), block_start, num_blocks);
35
36 ret = radix_tree_insert(&root->fs_info->dev_radix, block_start +
37 num_blocks - 1, lookup);
38 return ret;
39}
40
7eccb903
CM		 41u64 bh_blocknr(struct buffer_head *bh)
42{
43 int blkbits = bh->b_page->mapping->host->i_blkbits;
44 u64 blocknr = bh->b_page->index << (PAGE_CACHE_SHIFT - blkbits);
45 unsigned long offset;
46
47 if (PageHighMem(bh->b_page))
48 offset = (unsigned long)bh->b_data;
49 else
50 offset = bh->b_data - (char *)page_address(bh->b_page);
51 blocknr += offset >> (PAGE_CACHE_SHIFT - blkbits);
52 return blocknr;
53}
54
e20d96d6 55static int check_tree_block(struct btrfs_root *root, struct buffer_head *buf)
eb60ceac 56{
e20d96d6 57 struct btrfs_node *node = btrfs_buffer_node(buf);
7eccb903 58 if (bh_blocknr(buf) != btrfs_header_blocknr(&node->header)) {
8352d8a4
CM		 59 printk(KERN_CRIT "bh_blocknr(buf) is %Lu, header is %Lu\n",
60 bh_blocknr(buf), btrfs_header_blocknr(&node->header));
9a8dd150 61 BUG();
d98237b3 62 }
9a8dd150 63 return 0;
eb60ceac
CM		 64}
65
d98237b3
CM		 66struct buffer_head *btrfs_find_tree_block(struct btrfs_root *root, u64 blocknr)
67{
68 struct address_space *mapping = root->fs_info->btree_inode->i_mapping;
69 int blockbits = root->fs_info->sb->s_blocksize_bits;
70 unsigned long index = blocknr >> (PAGE_CACHE_SHIFT - blockbits);
71 struct page *page;
72 struct buffer_head *bh;
73 struct buffer_head *head;
74 struct buffer_head *ret = NULL;
75
2c90e5d6 76
d98237b3
CM		 77 page = find_lock_page(mapping, index);
78 if (!page)
79 return NULL;
80
81 if (!page_has_buffers(page))
82 goto out_unlock;
83
84 head = page_buffers(page);
85 bh = head;
86 do {
7eccb903 87 if (buffer_mapped(bh) && bh_blocknr(bh) == blocknr) {
d98237b3
CM		 88 ret = bh;
89 get_bh(bh);
90 goto out_unlock;
91 }
92 bh = bh->b_this_page;
93 } while (bh != head);
94out_unlock:
95 unlock_page(page);
d6025579 96 if (ret) {
22b0ebda 97 touch_buffer(ret);
d6025579 98 }
d98237b3
CM		 99 page_cache_release(page);
100 return ret;
101}
102
8352d8a4 103int btrfs_map_bh_to_logical(struct btrfs_root *root, struct buffer_head *bh,
7eccb903
CM		 104 u64 logical)
105{
106 struct dev_lookup *lookup[2];
7eccb903
CM		 107
108 int ret;
109
110 root = root->fs_info->dev_root;
111 ret = radix_tree_gang_lookup(&root->fs_info->dev_radix,
112 (void **)lookup,
113 (unsigned long)logical,
114 ARRAY_SIZE(lookup));
115 if (ret == 0 || lookup[0]->block_start > logical ||
116 lookup[0]->block_start + lookup[0]->num_blocks <= logical) {
117 ret = -ENOENT;
118 goto out;
119 }
120 bh->b_bdev = lookup[0]->bdev;
121 bh->b_blocknr = logical - lookup[0]->block_start;
7eccb903
CM		 122 set_buffer_mapped(bh);
123 ret = 0;
124out:
125 return ret;
126}
127
d98237b3
CM		 128struct buffer_head *btrfs_find_create_tree_block(struct btrfs_root *root,
129 u64 blocknr)
130{
131 struct address_space *mapping = root->fs_info->btree_inode->i_mapping;
132 int blockbits = root->fs_info->sb->s_blocksize_bits;
133 unsigned long index = blocknr >> (PAGE_CACHE_SHIFT - blockbits);
134 struct page *page;
135 struct buffer_head *bh;
136 struct buffer_head *head;
137 struct buffer_head *ret = NULL;
7eccb903 138 int err;
d98237b3 139 u64 first_block = index << (PAGE_CACHE_SHIFT - blockbits);
22b0ebda 140
d98237b3
CM		 141 page = grab_cache_page(mapping, index);
142 if (!page)
143 return NULL;
144
d98237b3
CM		 145 if (!page_has_buffers(page))
146 create_empty_buffers(page, root->fs_info->sb->s_blocksize, 0);
147 head = page_buffers(page);
148 bh = head;
149 do {
150 if (!buffer_mapped(bh)) {
8352d8a4 151 err = btrfs_map_bh_to_logical(root, bh, first_block);
7eccb903 152 BUG_ON(err);
d98237b3 153 }
7eccb903 154 if (bh_blocknr(bh) == blocknr) {
d98237b3
CM		 155 ret = bh;
156 get_bh(bh);
157 goto out_unlock;
158 }
159 bh = bh->b_this_page;
160 first_block++;
161 } while (bh != head);
162out_unlock:
163 unlock_page(page);
22b0ebda
CM		 164 if (ret)
165 touch_buffer(ret);
d98237b3
CM		 166 page_cache_release(page);
167 return ret;
168}
169
d98237b3
CM		 170static int btree_get_block(struct inode *inode, sector_t iblock,
171 struct buffer_head *bh, int create)
172{
7eccb903
CM		 173 int err;
174 struct btrfs_root *root = BTRFS_I(bh->b_page->mapping->host)->root;
8352d8a4 175 err = btrfs_map_bh_to_logical(root, bh, iblock);
7eccb903 176 return err;
d98237b3
CM		 177}
178
f254e52c
CM		 179int btrfs_csum_data(struct btrfs_root * root, char *data, size_t len,
180 char *result)
87cbda5c 181{
87cbda5c
CM		 182 struct scatterlist sg;
183 struct crypto_hash *tfm = root->fs_info->hash_tfm;
184 struct hash_desc desc;
185 int ret;
87cbda5c
CM		 186
187 desc.tfm = tfm;
188 desc.flags = 0;
f254e52c 189 sg_init_one(&sg, data, len);
87cbda5c 190 spin_lock(&root->fs_info->hash_lock);
22b0ebda 191 ret = crypto_hash_digest(&desc, &sg, 1, result);
87cbda5c
CM		 192 spin_unlock(&root->fs_info->hash_lock);
193 if (ret) {
194 printk("sha256 digest failed\n");
195 }
f254e52c
CM		 196 return ret;
197}
198static int csum_tree_block(struct btrfs_root *root, struct buffer_head *bh,
199 int verify)
200{
201 char result[BTRFS_CSUM_SIZE];
202 int ret;
203 struct btrfs_node *node;
204
205 ret = btrfs_csum_data(root, bh->b_data + BTRFS_CSUM_SIZE,
206 bh->b_size - BTRFS_CSUM_SIZE, result);
207 if (ret)
208 return ret;
87cbda5c 209 if (verify) {
f254e52c 210 if (memcmp(bh->b_data, result, BTRFS_CSUM_SIZE)) {
7eccb903
CM		 211 printk("checksum verify failed on %Lu\n",
212 bh_blocknr(bh));
f254e52c
CM		 213 return 1;
214 }
215 } else {
216 node = btrfs_buffer_node(bh);
22b0ebda 217 memcpy(node->header.csum, result, BTRFS_CSUM_SIZE);
f254e52c 218 }
87cbda5c
CM		 219 return 0;
220}
221
d98237b3 222static int btree_writepage(struct page *page, struct writeback_control *wbc)
ed2ff2cb 223{
87cbda5c 224 struct buffer_head *bh;
0f7d52f4 225 struct btrfs_root *root = BTRFS_I(page->mapping->host)->root;
87cbda5c 226 struct buffer_head *head;
87cbda5c
CM		 227 if (!page_has_buffers(page)) {
228 create_empty_buffers(page, root->fs_info->sb->s_blocksize,
229 (1 << BH_Dirty)|(1 << BH_Uptodate));
230 }
231 head = page_buffers(page);
232 bh = head;
233 do {
234 if (buffer_dirty(bh))
235 csum_tree_block(root, bh, 0);
236 bh = bh->b_this_page;
237 } while (bh != head);
d98237b3 238 return block_write_full_page(page, btree_get_block, wbc);
ed2ff2cb
CM		 239}
240
d98237b3 241static int btree_readpage(struct file * file, struct page * page)
eb60ceac 242{
d98237b3 243 return block_read_full_page(page, btree_get_block);
eb60ceac
CM		 244}
245
d98237b3
CM		 246static struct address_space_operations btree_aops = {
247 .readpage = btree_readpage,
248 .writepage = btree_writepage,
249 .sync_page = block_sync_page,
250};
251
e20d96d6 252struct buffer_head *read_tree_block(struct btrfs_root *root, u64 blocknr)
eb60ceac 253{
d98237b3 254 struct buffer_head *bh = NULL;
eb60ceac 255
d98237b3
CM		 256 bh = btrfs_find_create_tree_block(root, blocknr);
257 if (!bh)
258 return bh;
9d64272c
CM		 259 if (buffer_uptodate(bh))
260 goto uptodate;
d98237b3
CM		 261 lock_buffer(bh);
262 if (!buffer_uptodate(bh)) {
263 get_bh(bh);
264 bh->b_end_io = end_buffer_read_sync;
265 submit_bh(READ, bh);
266 wait_on_buffer(bh);
267 if (!buffer_uptodate(bh))
268 goto fail;
87cbda5c 269 csum_tree_block(root, bh, 1);
d98237b3
CM		 270 } else {
271 unlock_buffer(bh);
272 }
9d64272c 273uptodate:
d98237b3 274 if (check_tree_block(root, bh))
cfaa7295 275 BUG();
d98237b3
CM		 276 return bh;
277fail:
278 brelse(bh);
279 return NULL;
eb60ceac
CM		 280}
281
e089f05c 282int dirty_tree_block(struct btrfs_trans_handle *trans, struct btrfs_root *root,
e20d96d6 283 struct buffer_head *buf)
ed2ff2cb 284{
d6025579 285 WARN_ON(atomic_read(&buf->b_count) == 0);
e20d96d6 286 mark_buffer_dirty(buf);
ed2ff2cb
CM		 287 return 0;
288}
289
e089f05c 290int clean_tree_block(struct btrfs_trans_handle *trans, struct btrfs_root *root,
e20d96d6 291 struct buffer_head *buf)
ed2ff2cb 292{
d6025579 293 WARN_ON(atomic_read(&buf->b_count) == 0);
e20d96d6 294 clear_buffer_dirty(buf);
ed2ff2cb
CM		 295 return 0;
296}
297
2c90e5d6 298static int __setup_root(int blocksize,
9f5fae2f
CM		 299 struct btrfs_root *root,
300 struct btrfs_fs_info *fs_info,
e20d96d6 301 u64 objectid)
d97e63b6 302{
cfaa7295 303 root->node = NULL;
0f7d52f4 304 root->inode = NULL;
a28ec197 305 root->commit_root = NULL;
2c90e5d6 306 root->blocksize = blocksize;
123abc88 307 root->ref_cows = 0;
9f5fae2f 308 root->fs_info = fs_info;
0f7d52f4
CM		 309 root->objectid = objectid;
310 root->last_trans = 0;
1b05da2e
CM		 311 root->highest_inode = 0;
312 root->last_inode_alloc = 0;
3768f368
CM		 313 memset(&root->root_key, 0, sizeof(root->root_key));
314 memset(&root->root_item, 0, sizeof(root->root_item));
315 return 0;
316}
317
2c90e5d6 318static int find_and_setup_root(int blocksize,
9f5fae2f
CM		 319 struct btrfs_root *tree_root,
320 struct btrfs_fs_info *fs_info,
321 u64 objectid,
e20d96d6 322 struct btrfs_root *root)
3768f368
CM		 323{
324 int ret;
325
2c90e5d6 326 __setup_root(blocksize, root, fs_info, objectid);
3768f368
CM		 327 ret = btrfs_find_last_root(tree_root, objectid,
328 &root->root_item, &root->root_key);
329 BUG_ON(ret);
330
331 root->node = read_tree_block(root,
332 btrfs_root_blocknr(&root->root_item));
3768f368 333 BUG_ON(!root->node);
d97e63b6
CM		 334 return 0;
335}
336
0f7d52f4
CM		 337struct btrfs_root *btrfs_read_fs_root(struct btrfs_fs_info *fs_info,
338 struct btrfs_key *location)
339{
340 struct btrfs_root *root;
341 struct btrfs_root *tree_root = fs_info->tree_root;
342 struct btrfs_path *path;
343 struct btrfs_leaf *l;
1b05da2e 344 u64 highest_inode;
0f7d52f4
CM		 345 int ret = 0;
346
347printk("read_fs_root looking for %Lu %Lu %u\n", location->objectid, location->offset, location->flags);
2619ba1f
CM		 348 root = radix_tree_lookup(&fs_info->fs_roots_radix,
349 (unsigned long)location->objectid);
350 if (root) {
351printk("found %p in cache\n", root);
352 return root;
353 }
0f7d52f4
CM		 354 root = kmalloc(sizeof(*root), GFP_NOFS);
355 if (!root) {
356printk("failed1\n");
357 return ERR_PTR(-ENOMEM);
358 }
359 if (location->offset == (u64)-1) {
360 ret = find_and_setup_root(fs_info->sb->s_blocksize,
361 fs_info->tree_root, fs_info,
362 location->objectid, root);
363 if (ret) {
364printk("failed2\n");
365 kfree(root);
366 return ERR_PTR(ret);
367 }
368 goto insert;
369 }
370
371 __setup_root(fs_info->sb->s_blocksize, root, fs_info,
372 location->objectid);
373
374 path = btrfs_alloc_path();
375 BUG_ON(!path);
376 ret = btrfs_search_slot(NULL, tree_root, location, path, 0, 0);
377 if (ret != 0) {
378printk("internal search_slot gives us %d\n", ret);
379 if (ret > 0)
380 ret = -ENOENT;
381 goto out;
382 }
383 l = btrfs_buffer_leaf(path->nodes[0]);
384 memcpy(&root->root_item,
385 btrfs_item_ptr(l, path->slots[0], struct btrfs_root_item),
386 sizeof(root->root_item));
387 memcpy(&root->root_key, location, sizeof(*location));
388 ret = 0;
389out:
390 btrfs_release_path(root, path);
391 btrfs_free_path(path);
392 if (ret) {
393 kfree(root);
394 return ERR_PTR(ret);
395 }
396 root->node = read_tree_block(root,
397 btrfs_root_blocknr(&root->root_item));
398 BUG_ON(!root->node);
399insert:
400printk("inserting %p\n", root);
401 root->ref_cows = 1;
2619ba1f
CM		 402 ret = radix_tree_insert(&fs_info->fs_roots_radix,
403 (unsigned long)root->root_key.objectid,
0f7d52f4
CM		 404 root);
405 if (ret) {
406printk("radix_tree_insert gives us %d\n", ret);
407 brelse(root->node);
408 kfree(root);
409 return ERR_PTR(ret);
410 }
1b05da2e
CM		 411 ret = btrfs_find_highest_inode(root, &highest_inode);
412 if (ret == 0) {
413 root->highest_inode = highest_inode;
414 root->last_inode_alloc = highest_inode;
415printk("highest inode is %Lu\n", highest_inode);
416 }
0f7d52f4
CM		 417printk("all worked\n");
418 return root;
419}
420
8352d8a4
CM		 421int btrfs_open_disk(struct btrfs_root *root, u64 block_start, u64 num_blocks,
422 char *filename, int name_len)
423{
424 char *null_filename;
425 struct block_device *bdev;
426 int ret;
427
428 if (block_start == 0) {
429printk("skipping disk with block_start == 0\n");
430return 0;
431 }
432 null_filename = kmalloc(name_len + 1, GFP_NOFS);
433 if (!null_filename)
434 return -ENOMEM;
435 memcpy(null_filename, filename, name_len);
436 null_filename[name_len] = '\0';
437
438 bdev = open_bdev_excl(null_filename, O_RDWR, root->fs_info->sb);
439 if (IS_ERR(bdev)) {
440 ret = PTR_ERR(bdev);
441 goto out;
442 }
443 set_blocksize(bdev, root->fs_info->sb->s_blocksize);
444 ret = btrfs_insert_dev_radix(root, bdev, block_start, num_blocks);
445 BUG_ON(ret);
446 ret = 0;
447out:
448 kfree(null_filename);
449 return ret;
450}
451
452static int read_device_info(struct btrfs_root *root)
453{
454 struct btrfs_path *path;
455 int ret;
456 struct btrfs_key key;
457 struct btrfs_leaf *leaf;
458 struct btrfs_device_item *dev_item;
459 int nritems;
460 int slot;
461
462 root = root->fs_info->dev_root;
463
464 path = btrfs_alloc_path();
465 if (!path)
466 return -ENOMEM;
467 key.objectid = 0;
468 key.offset = 0;
469 key.flags = 0;
470 btrfs_set_key_type(&key, BTRFS_DEV_ITEM_KEY);
471
472 mutex_lock(&root->fs_info->fs_mutex);
473 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
474 leaf = btrfs_buffer_leaf(path->nodes[0]);
475 nritems = btrfs_header_nritems(&leaf->header);
476 while(1) {
477 slot = path->slots[0];
478 if (slot >= nritems) {
479 ret = btrfs_next_leaf(root, path);
480 if (ret)
481 break;
482 leaf = btrfs_buffer_leaf(path->nodes[0]);
483 nritems = btrfs_header_nritems(&leaf->header);
484 slot = path->slots[0];
485 }
486 btrfs_disk_key_to_cpu(&key, &leaf->items[slot].key);
487 if (btrfs_key_type(&key) != BTRFS_DEV_ITEM_KEY) {
488 path->slots[0]++;
489 continue;
490 }
491 dev_item = btrfs_item_ptr(leaf, slot, struct btrfs_device_item);
492printk("found key %Lu %Lu\n", key.objectid, key.offset);
493 ret = btrfs_open_disk(root, key.objectid, key.offset,
494 (char *)(dev_item + 1),
495 btrfs_device_pathlen(dev_item));
496 BUG_ON(ret);
497 path->slots[0]++;
498 }
499 btrfs_free_path(path);
500 mutex_unlock(&root->fs_info->fs_mutex);
501 return 0;
502}
503
2c90e5d6 504struct btrfs_root *open_ctree(struct super_block *sb)
2e635a27 505{
e20d96d6
CM		 506 struct btrfs_root *extent_root = kmalloc(sizeof(struct btrfs_root),
507 GFP_NOFS);
0bd93ba0
CM		 508 struct btrfs_root *dev_root = kmalloc(sizeof(struct btrfs_root),
509 GFP_NOFS);
e20d96d6
CM		 510 struct btrfs_root *tree_root = kmalloc(sizeof(struct btrfs_root),
511 GFP_NOFS);
e20d96d6
CM		 512 struct btrfs_fs_info *fs_info = kmalloc(sizeof(*fs_info),
513 GFP_NOFS);
eb60ceac 514 int ret;
2c90e5d6 515 struct btrfs_super_block *disk_super;
7eccb903 516 struct dev_lookup *dev_lookup;
eb60ceac 517
8ef97622
CM		 518 init_bit_radix(&fs_info->pinned_radix);
519 init_bit_radix(&fs_info->pending_del_radix);
0f7d52f4 520 INIT_RADIX_TREE(&fs_info->fs_roots_radix, GFP_NOFS);
7eccb903 521 INIT_RADIX_TREE(&fs_info->dev_radix, GFP_NOFS);
2c90e5d6 522 sb_set_blocksize(sb, 4096);
9f5fae2f 523 fs_info->running_transaction = NULL;
9f5fae2f
CM		 524 fs_info->tree_root = tree_root;
525 fs_info->extent_root = extent_root;
0bd93ba0 526 fs_info->dev_root = dev_root;
e20d96d6 527 fs_info->sb = sb;
d98237b3
CM		 528 fs_info->btree_inode = new_inode(sb);
529 fs_info->btree_inode->i_ino = 1;
2c90e5d6 530 fs_info->btree_inode->i_nlink = 1;
d98237b3
CM		 531 fs_info->btree_inode->i_size = sb->s_bdev->bd_inode->i_size;
532 fs_info->btree_inode->i_mapping->a_ops = &btree_aops;
0f7d52f4
CM		 533 BTRFS_I(fs_info->btree_inode)->root = tree_root;
534 memset(&BTRFS_I(fs_info->btree_inode)->location, 0,
535 sizeof(struct btrfs_key));
22b0ebda 536 insert_inode_hash(fs_info->btree_inode);
d98237b3 537 mapping_set_gfp_mask(fs_info->btree_inode->i_mapping, GFP_NOFS);
87cbda5c 538 fs_info->hash_tfm = crypto_alloc_hash("sha256", 0, CRYPTO_ALG_ASYNC);
30ae8467 539 spin_lock_init(&fs_info->hash_lock);
30ae8467 540 if (!fs_info->hash_tfm || IS_ERR(fs_info->hash_tfm)) {
87cbda5c
CM		 541 printk("failed to allocate sha256 hash\n");
542 return NULL;
543 }
79154b1b 544 mutex_init(&fs_info->trans_mutex);
d561c025 545 mutex_init(&fs_info->fs_mutex);
9f5fae2f
CM		 546 memset(&fs_info->current_insert, 0, sizeof(fs_info->current_insert));
547 memset(&fs_info->last_insert, 0, sizeof(fs_info->last_insert));
3768f368 548
0bd93ba0
CM		 549 __setup_root(sb->s_blocksize, dev_root,
550 fs_info, BTRFS_DEV_TREE_OBJECTID);
551
2c90e5d6
CM		 552 __setup_root(sb->s_blocksize, tree_root,
553 fs_info, BTRFS_ROOT_TREE_OBJECTID);
7eccb903
CM		 554
555 dev_lookup = kmalloc(sizeof(*dev_lookup), GFP_NOFS);
556 dev_lookup->block_start = 0;
557 dev_lookup->num_blocks = (u32)-2;
558 dev_lookup->bdev = sb->s_bdev;
559 ret = radix_tree_insert(&fs_info->dev_radix, (u32)-2, dev_lookup);
560 BUG_ON(ret);
2c90e5d6
CM		 561 fs_info->sb_buffer = read_tree_block(tree_root,
562 BTRFS_SUPER_INFO_OFFSET /
563 sb->s_blocksize);
d98237b3 564
0f7d52f4 565 if (!fs_info->sb_buffer)
d98237b3 566 return NULL;
d98237b3 567 disk_super = (struct btrfs_super_block *)fs_info->sb_buffer->b_data;
0f7d52f4 568 if (!btrfs_super_root(disk_super))
2c90e5d6 569 return NULL;
0f7d52f4 570
8352d8a4
CM		 571 i_size_write(fs_info->btree_inode,
572 btrfs_super_total_blocks(disk_super) <<
573 fs_info->btree_inode->i_blkbits);
574
7eccb903
CM		 575 radix_tree_delete(&fs_info->dev_radix, (u32)-2);
576 dev_lookup->block_start = btrfs_super_device_block_start(disk_super);
577 dev_lookup->num_blocks = btrfs_super_device_num_blocks(disk_super);
578 ret = radix_tree_insert(&fs_info->dev_radix,
579 dev_lookup->block_start +
8352d8a4 580 dev_lookup->num_blocks - 1, dev_lookup);
7eccb903
CM		 581 BUG_ON(ret);
582
d98237b3 583 fs_info->disk_super = disk_super;
8352d8a4 584
0bd93ba0
CM		 585 dev_root->node = read_tree_block(tree_root,
586 btrfs_super_device_root(disk_super));
8352d8a4
CM		 587
588 ret = read_device_info(dev_root);
589 BUG_ON(ret);
590
e20d96d6
CM		 591 tree_root->node = read_tree_block(tree_root,
592 btrfs_super_root(disk_super));
3768f368
CM		 593 BUG_ON(!tree_root->node);
594
2c90e5d6
CM		 595 mutex_lock(&fs_info->fs_mutex);
596 ret = find_and_setup_root(sb->s_blocksize, tree_root, fs_info,
e20d96d6 597 BTRFS_EXTENT_TREE_OBJECTID, extent_root);
3768f368
CM		 598 BUG_ON(ret);
599
0f7d52f4 600 fs_info->generation = btrfs_super_generation(disk_super) + 1;
d6e4a428
CM		 601 memset(&fs_info->kobj, 0, sizeof(fs_info->kobj));
602 kobj_set_kset_s(fs_info, btrfs_subsys);
603 kobject_set_name(&fs_info->kobj, "%s", sb->s_id);
604 kobject_register(&fs_info->kobj);
5be6f7f1 605 mutex_unlock(&fs_info->fs_mutex);
0f7d52f4 606 return tree_root;
eb60ceac
CM		 607}
608
e089f05c 609int write_ctree_super(struct btrfs_trans_handle *trans, struct btrfs_root
79154b1b 610 *root)
eb60ceac 611{
d5719762 612 struct buffer_head *bh = root->fs_info->sb_buffer;
2c90e5d6 613
d5719762 614 btrfs_set_super_root(root->fs_info->disk_super,
7eccb903 615 bh_blocknr(root->fs_info->tree_root->node));
d5719762 616 lock_buffer(bh);
2c90e5d6 617 WARN_ON(atomic_read(&bh->b_count) < 1);
d5719762 618 clear_buffer_dirty(bh);
87cbda5c 619 csum_tree_block(root, bh, 0);
d5719762
CM		 620 bh->b_end_io = end_buffer_write_sync;
621 get_bh(bh);
622 submit_bh(WRITE, bh);
623 wait_on_buffer(bh);
624 if (!buffer_uptodate(bh)) {
625 WARN_ON(1);
626 return -EIO;
cfaa7295
CM		 627 }
628 return 0;
629}
630
2619ba1f
CM		 631static int free_fs_root(struct btrfs_fs_info *fs_info, struct btrfs_root *root)
632{
633 radix_tree_delete(&fs_info->fs_roots_radix,
634 (unsigned long)root->root_key.objectid);
635 if (root->inode)
636 iput(root->inode);
637 if (root->node)
638 brelse(root->node);
639 if (root->commit_root)
640 brelse(root->commit_root);
641 kfree(root);
642 return 0;
643}
644
0f7d52f4
CM		 645int del_fs_roots(struct btrfs_fs_info *fs_info)
646{
647 int ret;
648 struct btrfs_root *gang[8];
649 int i;
650
651 while(1) {
652 ret = radix_tree_gang_lookup(&fs_info->fs_roots_radix,
653 (void **)gang, 0,
654 ARRAY_SIZE(gang));
655 if (!ret)
656 break;
2619ba1f
CM		 657 for (i = 0; i < ret; i++)
658 free_fs_root(fs_info, gang[i]);
0f7d52f4
CM		 659 }
660 return 0;
661}
7eccb903
CM		 662static int free_dev_radix(struct btrfs_fs_info *fs_info)
663{
664 struct dev_lookup *lookup[8];
665 struct block_device *super_bdev = fs_info->sb->s_bdev;
666 int ret;
667 int i;
668 while(1) {
669 ret = radix_tree_gang_lookup(&fs_info->dev_radix,
670 (void **)lookup, 0,
671 ARRAY_SIZE(lookup));
672 if (!ret)
673 break;
674 for (i = 0; i < ret; i++) {
675 if (lookup[i]->bdev != super_bdev)
676 close_bdev_excl(lookup[i]->bdev);
677 radix_tree_delete(&fs_info->dev_radix,
678 lookup[i]->block_start +
8352d8a4 679 lookup[i]->num_blocks - 1);
7eccb903
CM		 680 kfree(lookup[i]);
681 }
682 }
683 return 0;
684}
0f7d52f4 685
e20d96d6 686int close_ctree(struct btrfs_root *root)
cfaa7295 687{
3768f368 688 int ret;
e089f05c 689 struct btrfs_trans_handle *trans;
0f7d52f4 690 struct btrfs_fs_info *fs_info = root->fs_info;
e089f05c 691
0f7d52f4 692 mutex_lock(&fs_info->fs_mutex);
79154b1b
CM		 693 trans = btrfs_start_transaction(root, 1);
694 btrfs_commit_transaction(trans, root);
695 /* run commit again to drop the original snapshot */
696 trans = btrfs_start_transaction(root, 1);
697 btrfs_commit_transaction(trans, root);
698 ret = btrfs_write_and_wait_transaction(NULL, root);
3768f368 699 BUG_ON(ret);
79154b1b 700 write_ctree_super(NULL, root);
0f7d52f4
CM		 701 mutex_unlock(&fs_info->fs_mutex);
702
703 if (fs_info->extent_root->node)
704 btrfs_block_release(fs_info->extent_root,
705 fs_info->extent_root->node);
0bd93ba0
CM		 706 if (fs_info->dev_root->node)
707 btrfs_block_release(fs_info->dev_root,
708 fs_info->dev_root->node);
0f7d52f4
CM		 709 if (fs_info->tree_root->node)
710 btrfs_block_release(fs_info->tree_root,
711 fs_info->tree_root->node);
712 btrfs_block_release(root, fs_info->sb_buffer);
713 crypto_free_hash(fs_info->hash_tfm);
714 truncate_inode_pages(fs_info->btree_inode->i_mapping, 0);
715 iput(fs_info->btree_inode);
7eccb903
CM		 716
717 free_dev_radix(fs_info);
0f7d52f4
CM		 718 del_fs_roots(fs_info);
719 kfree(fs_info->extent_root);
0f7d52f4
CM		 720 kfree(fs_info->tree_root);
721 kobject_unregister(&fs_info->kobj);
eb60ceac
CM		 722 return 0;
723}
724
e20d96d6 725void btrfs_block_release(struct btrfs_root *root, struct buffer_head *buf)
eb60ceac 726{
7cfcc17e 727 brelse(buf);
eb60ceac
CM		 728}
729
Linux 6.x block layer and io_uring tree(s)