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Commit | Line | Data |
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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> | |
eb60ceac CM |
6 | #include "ctree.h" |
7 | #include "disk-io.h" | |
e089f05c | 8 | #include "transaction.h" |
eb60ceac | 9 | |
d98237b3 | 10 | |
e20d96d6 | 11 | static int check_tree_block(struct btrfs_root *root, struct buffer_head *buf) |
eb60ceac | 12 | { |
e20d96d6 | 13 | struct btrfs_node *node = btrfs_buffer_node(buf); |
d98237b3 | 14 | if (buf->b_blocknr != btrfs_header_blocknr(&node->header)) { |
9a8dd150 | 15 | BUG(); |
d98237b3 | 16 | } |
e20d96d6 | 17 | if (root->node && btrfs_header_parentid(&node->header) != |
df2ce34c | 18 | btrfs_header_parentid(btrfs_buffer_header(root->node))) { |
7f5c1516 | 19 | BUG(); |
df2ce34c | 20 | } |
9a8dd150 | 21 | return 0; |
eb60ceac CM |
22 | } |
23 | ||
d98237b3 CM |
24 | struct buffer_head *btrfs_find_tree_block(struct btrfs_root *root, u64 blocknr) |
25 | { | |
26 | struct address_space *mapping = root->fs_info->btree_inode->i_mapping; | |
27 | int blockbits = root->fs_info->sb->s_blocksize_bits; | |
28 | unsigned long index = blocknr >> (PAGE_CACHE_SHIFT - blockbits); | |
29 | struct page *page; | |
30 | struct buffer_head *bh; | |
31 | struct buffer_head *head; | |
32 | struct buffer_head *ret = NULL; | |
33 | ||
34 | page = find_lock_page(mapping, index); | |
35 | if (!page) | |
36 | return NULL; | |
37 | ||
38 | if (!page_has_buffers(page)) | |
39 | goto out_unlock; | |
40 | ||
41 | head = page_buffers(page); | |
42 | bh = head; | |
43 | do { | |
44 | if (buffer_mapped(bh) && bh->b_blocknr == blocknr) { | |
45 | ret = bh; | |
46 | get_bh(bh); | |
47 | goto out_unlock; | |
48 | } | |
49 | bh = bh->b_this_page; | |
50 | } while (bh != head); | |
51 | out_unlock: | |
52 | unlock_page(page); | |
53 | page_cache_release(page); | |
54 | return ret; | |
55 | } | |
56 | ||
57 | struct buffer_head *btrfs_find_create_tree_block(struct btrfs_root *root, | |
58 | u64 blocknr) | |
59 | { | |
60 | struct address_space *mapping = root->fs_info->btree_inode->i_mapping; | |
61 | int blockbits = root->fs_info->sb->s_blocksize_bits; | |
62 | unsigned long index = blocknr >> (PAGE_CACHE_SHIFT - blockbits); | |
63 | struct page *page; | |
64 | struct buffer_head *bh; | |
65 | struct buffer_head *head; | |
66 | struct buffer_head *ret = NULL; | |
67 | u64 first_block = index << (PAGE_CACHE_SHIFT - blockbits); | |
68 | page = grab_cache_page(mapping, index); | |
69 | if (!page) | |
70 | return NULL; | |
71 | ||
d98237b3 CM |
72 | if (!page_has_buffers(page)) |
73 | create_empty_buffers(page, root->fs_info->sb->s_blocksize, 0); | |
74 | head = page_buffers(page); | |
75 | bh = head; | |
76 | do { | |
77 | if (!buffer_mapped(bh)) { | |
78 | bh->b_bdev = root->fs_info->sb->s_bdev; | |
79 | bh->b_blocknr = first_block; | |
80 | set_buffer_mapped(bh); | |
81 | } | |
82 | if (bh->b_blocknr == blocknr) { | |
83 | ret = bh; | |
84 | get_bh(bh); | |
85 | goto out_unlock; | |
86 | } | |
87 | bh = bh->b_this_page; | |
88 | first_block++; | |
89 | } while (bh != head); | |
90 | out_unlock: | |
91 | unlock_page(page); | |
92 | page_cache_release(page); | |
93 | return ret; | |
94 | } | |
95 | ||
96 | static sector_t max_block(struct block_device *bdev) | |
97 | { | |
98 | sector_t retval = ~((sector_t)0); | |
99 | loff_t sz = i_size_read(bdev->bd_inode); | |
100 | ||
101 | if (sz) { | |
102 | unsigned int size = block_size(bdev); | |
103 | unsigned int sizebits = blksize_bits(size); | |
104 | retval = (sz >> sizebits); | |
105 | } | |
106 | return retval; | |
107 | } | |
108 | ||
109 | static int btree_get_block(struct inode *inode, sector_t iblock, | |
110 | struct buffer_head *bh, int create) | |
111 | { | |
112 | if (iblock >= max_block(inode->i_sb->s_bdev)) { | |
113 | if (create) | |
114 | return -EIO; | |
115 | ||
116 | /* | |
117 | * for reads, we're just trying to fill a partial page. | |
118 | * return a hole, they will have to call get_block again | |
119 | * before they can fill it, and they will get -EIO at that | |
120 | * time | |
121 | */ | |
122 | return 0; | |
123 | } | |
124 | bh->b_bdev = inode->i_sb->s_bdev; | |
125 | bh->b_blocknr = iblock; | |
126 | set_buffer_mapped(bh); | |
127 | return 0; | |
128 | } | |
129 | ||
f254e52c CM |
130 | int btrfs_csum_data(struct btrfs_root * root, char *data, size_t len, |
131 | char *result) | |
87cbda5c | 132 | { |
87cbda5c CM |
133 | struct scatterlist sg; |
134 | struct crypto_hash *tfm = root->fs_info->hash_tfm; | |
135 | struct hash_desc desc; | |
136 | int ret; | |
87cbda5c CM |
137 | |
138 | desc.tfm = tfm; | |
139 | desc.flags = 0; | |
f254e52c | 140 | sg_init_one(&sg, data, len); |
87cbda5c | 141 | spin_lock(&root->fs_info->hash_lock); |
f254e52c | 142 | ret = crypto_hash_digest(&desc, &sg, len, result); |
87cbda5c CM |
143 | spin_unlock(&root->fs_info->hash_lock); |
144 | if (ret) { | |
145 | printk("sha256 digest failed\n"); | |
146 | } | |
f254e52c CM |
147 | return ret; |
148 | } | |
149 | static int csum_tree_block(struct btrfs_root *root, struct buffer_head *bh, | |
150 | int verify) | |
151 | { | |
152 | char result[BTRFS_CSUM_SIZE]; | |
153 | int ret; | |
154 | struct btrfs_node *node; | |
155 | ||
156 | ret = btrfs_csum_data(root, bh->b_data + BTRFS_CSUM_SIZE, | |
157 | bh->b_size - BTRFS_CSUM_SIZE, result); | |
158 | if (ret) | |
159 | return ret; | |
87cbda5c | 160 | if (verify) { |
f254e52c CM |
161 | if (memcmp(bh->b_data, result, BTRFS_CSUM_SIZE)) { |
162 | printk("checksum verify failed on %lu\n", | |
163 | bh->b_blocknr); | |
164 | return 1; | |
165 | } | |
166 | } else { | |
167 | node = btrfs_buffer_node(bh); | |
168 | memcpy(&node->header.csum, result, BTRFS_CSUM_SIZE); | |
169 | } | |
87cbda5c CM |
170 | return 0; |
171 | } | |
172 | ||
d98237b3 | 173 | static int btree_writepage(struct page *page, struct writeback_control *wbc) |
ed2ff2cb | 174 | { |
87cbda5c CM |
175 | struct buffer_head *bh; |
176 | struct btrfs_root *root = btrfs_sb(page->mapping->host->i_sb); | |
177 | struct buffer_head *head; | |
178 | ||
179 | if (!page_has_buffers(page)) { | |
180 | create_empty_buffers(page, root->fs_info->sb->s_blocksize, | |
181 | (1 << BH_Dirty)|(1 << BH_Uptodate)); | |
182 | } | |
183 | head = page_buffers(page); | |
184 | bh = head; | |
185 | do { | |
186 | if (buffer_dirty(bh)) | |
187 | csum_tree_block(root, bh, 0); | |
188 | bh = bh->b_this_page; | |
189 | } while (bh != head); | |
d98237b3 | 190 | return block_write_full_page(page, btree_get_block, wbc); |
ed2ff2cb CM |
191 | } |
192 | ||
d98237b3 | 193 | static int btree_readpage(struct file * file, struct page * page) |
eb60ceac | 194 | { |
d98237b3 | 195 | return block_read_full_page(page, btree_get_block); |
eb60ceac CM |
196 | } |
197 | ||
d98237b3 CM |
198 | static struct address_space_operations btree_aops = { |
199 | .readpage = btree_readpage, | |
200 | .writepage = btree_writepage, | |
201 | .sync_page = block_sync_page, | |
202 | }; | |
203 | ||
e20d96d6 | 204 | struct buffer_head *read_tree_block(struct btrfs_root *root, u64 blocknr) |
eb60ceac | 205 | { |
d98237b3 | 206 | struct buffer_head *bh = NULL; |
eb60ceac | 207 | |
d98237b3 CM |
208 | bh = btrfs_find_create_tree_block(root, blocknr); |
209 | if (!bh) | |
210 | return bh; | |
211 | lock_buffer(bh); | |
212 | if (!buffer_uptodate(bh)) { | |
213 | get_bh(bh); | |
214 | bh->b_end_io = end_buffer_read_sync; | |
215 | submit_bh(READ, bh); | |
216 | wait_on_buffer(bh); | |
217 | if (!buffer_uptodate(bh)) | |
218 | goto fail; | |
87cbda5c | 219 | csum_tree_block(root, bh, 1); |
d98237b3 CM |
220 | } else { |
221 | unlock_buffer(bh); | |
222 | } | |
223 | if (check_tree_block(root, bh)) | |
cfaa7295 | 224 | BUG(); |
d98237b3 CM |
225 | return bh; |
226 | fail: | |
227 | brelse(bh); | |
228 | return NULL; | |
229 | ||
eb60ceac CM |
230 | } |
231 | ||
e089f05c | 232 | int dirty_tree_block(struct btrfs_trans_handle *trans, struct btrfs_root *root, |
e20d96d6 | 233 | struct buffer_head *buf) |
ed2ff2cb | 234 | { |
e20d96d6 | 235 | mark_buffer_dirty(buf); |
ed2ff2cb CM |
236 | return 0; |
237 | } | |
238 | ||
e089f05c | 239 | int clean_tree_block(struct btrfs_trans_handle *trans, struct btrfs_root *root, |
e20d96d6 | 240 | struct buffer_head *buf) |
ed2ff2cb | 241 | { |
e20d96d6 | 242 | clear_buffer_dirty(buf); |
ed2ff2cb CM |
243 | return 0; |
244 | } | |
245 | ||
123abc88 | 246 | static int __setup_root(struct btrfs_super_block *super, |
9f5fae2f CM |
247 | struct btrfs_root *root, |
248 | struct btrfs_fs_info *fs_info, | |
e20d96d6 | 249 | u64 objectid) |
d97e63b6 | 250 | { |
cfaa7295 | 251 | root->node = NULL; |
a28ec197 | 252 | root->commit_root = NULL; |
123abc88 CM |
253 | root->blocksize = btrfs_super_blocksize(super); |
254 | root->ref_cows = 0; | |
9f5fae2f | 255 | root->fs_info = fs_info; |
3768f368 CM |
256 | memset(&root->root_key, 0, sizeof(root->root_key)); |
257 | memset(&root->root_item, 0, sizeof(root->root_item)); | |
258 | return 0; | |
259 | } | |
260 | ||
123abc88 | 261 | static int find_and_setup_root(struct btrfs_super_block *super, |
9f5fae2f CM |
262 | struct btrfs_root *tree_root, |
263 | struct btrfs_fs_info *fs_info, | |
264 | u64 objectid, | |
e20d96d6 | 265 | struct btrfs_root *root) |
3768f368 CM |
266 | { |
267 | int ret; | |
268 | ||
e20d96d6 | 269 | __setup_root(super, root, fs_info, objectid); |
3768f368 CM |
270 | ret = btrfs_find_last_root(tree_root, objectid, |
271 | &root->root_item, &root->root_key); | |
272 | BUG_ON(ret); | |
273 | ||
274 | root->node = read_tree_block(root, | |
275 | btrfs_root_blocknr(&root->root_item)); | |
3768f368 | 276 | BUG_ON(!root->node); |
d97e63b6 CM |
277 | return 0; |
278 | } | |
279 | ||
e20d96d6 CM |
280 | struct btrfs_root *open_ctree(struct super_block *sb, |
281 | struct buffer_head *sb_buffer, | |
282 | struct btrfs_super_block *disk_super) | |
2e635a27 | 283 | { |
e20d96d6 CM |
284 | struct btrfs_root *root = kmalloc(sizeof(struct btrfs_root), |
285 | GFP_NOFS); | |
286 | struct btrfs_root *extent_root = kmalloc(sizeof(struct btrfs_root), | |
287 | GFP_NOFS); | |
288 | struct btrfs_root *tree_root = kmalloc(sizeof(struct btrfs_root), | |
289 | GFP_NOFS); | |
290 | struct btrfs_root *inode_root = kmalloc(sizeof(struct btrfs_root), | |
291 | GFP_NOFS); | |
292 | struct btrfs_fs_info *fs_info = kmalloc(sizeof(*fs_info), | |
293 | GFP_NOFS); | |
eb60ceac CM |
294 | int ret; |
295 | ||
87cbda5c | 296 | if (!btrfs_super_root(disk_super)) { |
e20d96d6 | 297 | return NULL; |
87cbda5c | 298 | } |
8ef97622 CM |
299 | init_bit_radix(&fs_info->pinned_radix); |
300 | init_bit_radix(&fs_info->pending_del_radix); | |
d98237b3 | 301 | sb_set_blocksize(sb, sb_buffer->b_size); |
9f5fae2f CM |
302 | fs_info->running_transaction = NULL; |
303 | fs_info->fs_root = root; | |
304 | fs_info->tree_root = tree_root; | |
305 | fs_info->extent_root = extent_root; | |
306 | fs_info->inode_root = inode_root; | |
307 | fs_info->last_inode_alloc = 0; | |
308 | fs_info->last_inode_alloc_dirid = 0; | |
e20d96d6 | 309 | fs_info->disk_super = disk_super; |
e20d96d6 | 310 | fs_info->sb = sb; |
d98237b3 CM |
311 | fs_info->btree_inode = new_inode(sb); |
312 | fs_info->btree_inode->i_ino = 1; | |
313 | fs_info->btree_inode->i_size = sb->s_bdev->bd_inode->i_size; | |
314 | fs_info->btree_inode->i_mapping->a_ops = &btree_aops; | |
315 | mapping_set_gfp_mask(fs_info->btree_inode->i_mapping, GFP_NOFS); | |
87cbda5c | 316 | fs_info->hash_tfm = crypto_alloc_hash("sha256", 0, CRYPTO_ALG_ASYNC); |
30ae8467 CM |
317 | spin_lock_init(&fs_info->hash_lock); |
318 | ||
319 | if (!fs_info->hash_tfm || IS_ERR(fs_info->hash_tfm)) { | |
87cbda5c CM |
320 | printk("failed to allocate sha256 hash\n"); |
321 | return NULL; | |
322 | } | |
d98237b3 | 323 | |
79154b1b | 324 | mutex_init(&fs_info->trans_mutex); |
d561c025 | 325 | mutex_init(&fs_info->fs_mutex); |
9f5fae2f CM |
326 | memset(&fs_info->current_insert, 0, sizeof(fs_info->current_insert)); |
327 | memset(&fs_info->last_insert, 0, sizeof(fs_info->last_insert)); | |
3768f368 | 328 | |
e20d96d6 | 329 | __setup_root(disk_super, tree_root, fs_info, BTRFS_ROOT_TREE_OBJECTID); |
d98237b3 CM |
330 | |
331 | fs_info->sb_buffer = read_tree_block(tree_root, sb_buffer->b_blocknr); | |
332 | ||
87cbda5c CM |
333 | if (!fs_info->sb_buffer) { |
334 | printk("failed2\n"); | |
d98237b3 | 335 | return NULL; |
87cbda5c | 336 | } |
d98237b3 CM |
337 | brelse(sb_buffer); |
338 | sb_buffer = NULL; | |
339 | disk_super = (struct btrfs_super_block *)fs_info->sb_buffer->b_data; | |
340 | fs_info->disk_super = disk_super; | |
341 | ||
e20d96d6 CM |
342 | tree_root->node = read_tree_block(tree_root, |
343 | btrfs_super_root(disk_super)); | |
3768f368 CM |
344 | BUG_ON(!tree_root->node); |
345 | ||
e20d96d6 CM |
346 | ret = find_and_setup_root(disk_super, tree_root, fs_info, |
347 | BTRFS_EXTENT_TREE_OBJECTID, extent_root); | |
3768f368 CM |
348 | BUG_ON(ret); |
349 | ||
e20d96d6 CM |
350 | ret = find_and_setup_root(disk_super, tree_root, fs_info, |
351 | BTRFS_INODE_MAP_OBJECTID, inode_root); | |
9f5fae2f CM |
352 | BUG_ON(ret); |
353 | ||
e20d96d6 CM |
354 | ret = find_and_setup_root(disk_super, tree_root, fs_info, |
355 | BTRFS_FS_TREE_OBJECTID, root); | |
3768f368 | 356 | BUG_ON(ret); |
a28ec197 | 357 | root->commit_root = root->node; |
e20d96d6 | 358 | get_bh(root->node); |
3768f368 | 359 | root->ref_cows = 1; |
293ffd5f | 360 | root->fs_info->generation = root->root_key.offset + 1; |
eb60ceac CM |
361 | return root; |
362 | } | |
363 | ||
e089f05c | 364 | int write_ctree_super(struct btrfs_trans_handle *trans, struct btrfs_root |
79154b1b | 365 | *root) |
eb60ceac | 366 | { |
d5719762 CM |
367 | struct buffer_head *bh = root->fs_info->sb_buffer; |
368 | btrfs_set_super_root(root->fs_info->disk_super, | |
369 | root->fs_info->tree_root->node->b_blocknr); | |
370 | lock_buffer(bh); | |
371 | clear_buffer_dirty(bh); | |
87cbda5c | 372 | csum_tree_block(root, bh, 0); |
d5719762 CM |
373 | bh->b_end_io = end_buffer_write_sync; |
374 | get_bh(bh); | |
375 | submit_bh(WRITE, bh); | |
376 | wait_on_buffer(bh); | |
377 | if (!buffer_uptodate(bh)) { | |
378 | WARN_ON(1); | |
379 | return -EIO; | |
cfaa7295 CM |
380 | } |
381 | return 0; | |
382 | } | |
383 | ||
e20d96d6 | 384 | int close_ctree(struct btrfs_root *root) |
cfaa7295 | 385 | { |
3768f368 | 386 | int ret; |
e089f05c CM |
387 | struct btrfs_trans_handle *trans; |
388 | ||
79154b1b CM |
389 | trans = btrfs_start_transaction(root, 1); |
390 | btrfs_commit_transaction(trans, root); | |
391 | /* run commit again to drop the original snapshot */ | |
392 | trans = btrfs_start_transaction(root, 1); | |
393 | btrfs_commit_transaction(trans, root); | |
394 | ret = btrfs_write_and_wait_transaction(NULL, root); | |
3768f368 | 395 | BUG_ON(ret); |
79154b1b | 396 | write_ctree_super(NULL, root); |
ed2ff2cb | 397 | |
cfaa7295 | 398 | if (root->node) |
234b63a0 | 399 | btrfs_block_release(root, root->node); |
9f5fae2f CM |
400 | if (root->fs_info->extent_root->node) |
401 | btrfs_block_release(root->fs_info->extent_root, | |
402 | root->fs_info->extent_root->node); | |
403 | if (root->fs_info->inode_root->node) | |
404 | btrfs_block_release(root->fs_info->inode_root, | |
405 | root->fs_info->inode_root->node); | |
406 | if (root->fs_info->tree_root->node) | |
407 | btrfs_block_release(root->fs_info->tree_root, | |
408 | root->fs_info->tree_root->node); | |
234b63a0 | 409 | btrfs_block_release(root, root->commit_root); |
e20d96d6 | 410 | btrfs_block_release(root, root->fs_info->sb_buffer); |
87cbda5c | 411 | crypto_free_hash(root->fs_info->hash_tfm); |
30ae8467 | 412 | truncate_inode_pages(root->fs_info->btree_inode->i_mapping, 0); |
d98237b3 | 413 | iput(root->fs_info->btree_inode); |
e20d96d6 CM |
414 | kfree(root->fs_info->extent_root); |
415 | kfree(root->fs_info->inode_root); | |
416 | kfree(root->fs_info->tree_root); | |
417 | kfree(root->fs_info); | |
418 | kfree(root); | |
eb60ceac CM |
419 | return 0; |
420 | } | |
421 | ||
e20d96d6 | 422 | void btrfs_block_release(struct btrfs_root *root, struct buffer_head *buf) |
eb60ceac | 423 | { |
e20d96d6 | 424 | brelse(buf); |
eb60ceac CM |
425 | } |
426 |