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