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6cbd5570 CM |
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 | ||
eb60ceac CM |
19 | #include "ctree.h" |
20 | #include "disk-io.h" | |
7f5c1516 | 21 | #include "transaction.h" |
9a8dd150 | 22 | |
e089f05c CM |
23 | static int split_node(struct btrfs_trans_handle *trans, struct btrfs_root |
24 | *root, struct btrfs_path *path, int level); | |
25 | static int split_leaf(struct btrfs_trans_handle *trans, struct btrfs_root | |
d4dbff95 CM |
26 | *root, struct btrfs_key *ins_key, |
27 | struct btrfs_path *path, int data_size); | |
e089f05c | 28 | static int push_node_left(struct btrfs_trans_handle *trans, struct btrfs_root |
e20d96d6 | 29 | *root, struct buffer_head *dst, struct buffer_head |
e089f05c CM |
30 | *src); |
31 | static int balance_node_right(struct btrfs_trans_handle *trans, struct | |
e20d96d6 CM |
32 | btrfs_root *root, struct buffer_head *dst_buf, |
33 | struct buffer_head *src_buf); | |
e089f05c CM |
34 | static int del_ptr(struct btrfs_trans_handle *trans, struct btrfs_root *root, |
35 | struct btrfs_path *path, int level, int slot); | |
d97e63b6 | 36 | |
df24a2b9 | 37 | inline void btrfs_init_path(struct btrfs_path *p) |
2c90e5d6 | 38 | { |
df24a2b9 | 39 | memset(p, 0, sizeof(*p)); |
2c90e5d6 CM |
40 | } |
41 | ||
df24a2b9 | 42 | struct btrfs_path *btrfs_alloc_path(void) |
2c90e5d6 | 43 | { |
df24a2b9 CM |
44 | struct btrfs_path *path; |
45 | path = kmem_cache_alloc(btrfs_path_cachep, GFP_NOFS); | |
46 | if (path) | |
47 | btrfs_init_path(path); | |
48 | return path; | |
2c90e5d6 CM |
49 | } |
50 | ||
df24a2b9 | 51 | void btrfs_free_path(struct btrfs_path *p) |
be0e5c09 | 52 | { |
df24a2b9 CM |
53 | btrfs_release_path(NULL, p); |
54 | kmem_cache_free(btrfs_path_cachep, p); | |
be0e5c09 CM |
55 | } |
56 | ||
234b63a0 | 57 | void btrfs_release_path(struct btrfs_root *root, struct btrfs_path *p) |
eb60ceac CM |
58 | { |
59 | int i; | |
234b63a0 | 60 | for (i = 0; i < BTRFS_MAX_LEVEL; i++) { |
eb60ceac CM |
61 | if (!p->nodes[i]) |
62 | break; | |
234b63a0 | 63 | btrfs_block_release(root, p->nodes[i]); |
eb60ceac | 64 | } |
aa5d6bed | 65 | memset(p, 0, sizeof(*p)); |
eb60ceac CM |
66 | } |
67 | ||
6702ed49 | 68 | static int __btrfs_cow_block(struct btrfs_trans_handle *trans, struct btrfs_root |
e20d96d6 CM |
69 | *root, struct buffer_head *buf, struct buffer_head |
70 | *parent, int parent_slot, struct buffer_head | |
6702ed49 | 71 | **cow_ret, u64 search_start, u64 empty_size) |
02217ed2 | 72 | { |
e20d96d6 CM |
73 | struct buffer_head *cow; |
74 | struct btrfs_node *cow_node; | |
6702ed49 CM |
75 | int ret = 0; |
76 | int different_trans = 0; | |
02217ed2 | 77 | |
6702ed49 | 78 | WARN_ON(root->ref_cows && trans->transid != root->last_trans); |
ccd467d6 | 79 | WARN_ON(!buffer_uptodate(buf)); |
6702ed49 | 80 | cow = btrfs_alloc_free_block(trans, root, search_start, empty_size); |
54aa1f4d CM |
81 | if (IS_ERR(cow)) |
82 | return PTR_ERR(cow); | |
6702ed49 | 83 | |
e20d96d6 | 84 | cow_node = btrfs_buffer_node(cow); |
2c90e5d6 CM |
85 | if (buf->b_size != root->blocksize || cow->b_size != root->blocksize) |
86 | WARN_ON(1); | |
6702ed49 | 87 | |
e20d96d6 | 88 | memcpy(cow_node, btrfs_buffer_node(buf), root->blocksize); |
7eccb903 | 89 | btrfs_set_header_blocknr(&cow_node->header, bh_blocknr(cow)); |
7f5c1516 | 90 | btrfs_set_header_generation(&cow_node->header, trans->transid); |
4d775673 | 91 | btrfs_set_header_owner(&cow_node->header, root->root_key.objectid); |
6702ed49 CM |
92 | |
93 | WARN_ON(btrfs_header_generation(btrfs_buffer_header(buf)) > | |
94 | trans->transid); | |
95 | if (btrfs_header_generation(btrfs_buffer_header(buf)) != | |
96 | trans->transid) { | |
97 | different_trans = 1; | |
98 | ret = btrfs_inc_ref(trans, root, buf); | |
99 | if (ret) | |
100 | return ret; | |
101 | } else { | |
6702ed49 CM |
102 | clean_tree_block(trans, root, buf); |
103 | } | |
104 | ||
02217ed2 CM |
105 | if (buf == root->node) { |
106 | root->node = cow; | |
e20d96d6 | 107 | get_bh(cow); |
2c90e5d6 | 108 | if (buf != root->commit_root) { |
7eccb903 | 109 | btrfs_free_extent(trans, root, bh_blocknr(buf), 1, 1); |
2c90e5d6 | 110 | } |
234b63a0 | 111 | btrfs_block_release(root, buf); |
02217ed2 | 112 | } else { |
e20d96d6 | 113 | btrfs_set_node_blockptr(btrfs_buffer_node(parent), parent_slot, |
7eccb903 | 114 | bh_blocknr(cow)); |
d6025579 | 115 | btrfs_mark_buffer_dirty(parent); |
6702ed49 CM |
116 | WARN_ON(btrfs_header_generation(btrfs_buffer_header(parent)) != |
117 | trans->transid); | |
7eccb903 | 118 | btrfs_free_extent(trans, root, bh_blocknr(buf), 1, 1); |
02217ed2 | 119 | } |
234b63a0 | 120 | btrfs_block_release(root, buf); |
ccd467d6 | 121 | btrfs_mark_buffer_dirty(cow); |
2c90e5d6 | 122 | *cow_ret = cow; |
02217ed2 CM |
123 | return 0; |
124 | } | |
125 | ||
6702ed49 CM |
126 | int btrfs_cow_block(struct btrfs_trans_handle *trans, struct btrfs_root |
127 | *root, struct buffer_head *buf, struct buffer_head | |
128 | *parent, int parent_slot, struct buffer_head | |
129 | **cow_ret) | |
130 | { | |
131 | u64 search_start; | |
132 | if (trans->transaction != root->fs_info->running_transaction) { | |
133 | printk(KERN_CRIT "trans %Lu running %Lu\n", trans->transid, | |
134 | root->fs_info->running_transaction->transid); | |
135 | WARN_ON(1); | |
136 | } | |
137 | if (trans->transid != root->fs_info->generation) { | |
138 | printk(KERN_CRIT "trans %Lu running %Lu\n", trans->transid, | |
139 | root->fs_info->generation); | |
140 | WARN_ON(1); | |
141 | } | |
142 | if (btrfs_header_generation(btrfs_buffer_header(buf)) == | |
143 | trans->transid) { | |
144 | *cow_ret = buf; | |
145 | return 0; | |
146 | } | |
147 | ||
148 | search_start = bh_blocknr(buf) & ~((u64)65535); | |
149 | return __btrfs_cow_block(trans, root, buf, parent, | |
150 | parent_slot, cow_ret, search_start, 0); | |
151 | } | |
152 | ||
153 | static int close_blocks(u64 blocknr, u64 other) | |
154 | { | |
155 | if (blocknr < other && other - blocknr < 8) | |
156 | return 1; | |
157 | if (blocknr > other && blocknr - other < 8) | |
158 | return 1; | |
159 | return 0; | |
160 | } | |
161 | ||
162 | int btrfs_realloc_node(struct btrfs_trans_handle *trans, | |
163 | struct btrfs_root *root, struct buffer_head *parent, | |
e9d0b13b | 164 | int cache_only, u64 *last_ret) |
6702ed49 CM |
165 | { |
166 | struct btrfs_node *parent_node; | |
167 | struct buffer_head *cur_bh; | |
168 | struct buffer_head *tmp_bh; | |
169 | u64 blocknr; | |
e9d0b13b CM |
170 | u64 search_start = *last_ret; |
171 | u64 last_block = 0; | |
6702ed49 CM |
172 | u64 other; |
173 | u32 parent_nritems; | |
174 | int start_slot; | |
175 | int end_slot; | |
176 | int i; | |
177 | int err = 0; | |
f2183bde | 178 | int parent_level; |
6702ed49 CM |
179 | |
180 | if (trans->transaction != root->fs_info->running_transaction) { | |
181 | printk(KERN_CRIT "trans %Lu running %Lu\n", trans->transid, | |
182 | root->fs_info->running_transaction->transid); | |
183 | WARN_ON(1); | |
184 | } | |
185 | if (trans->transid != root->fs_info->generation) { | |
186 | printk(KERN_CRIT "trans %Lu running %Lu\n", trans->transid, | |
187 | root->fs_info->generation); | |
188 | WARN_ON(1); | |
189 | } | |
190 | parent_node = btrfs_buffer_node(parent); | |
191 | parent_nritems = btrfs_header_nritems(&parent_node->header); | |
f2183bde | 192 | parent_level = btrfs_header_level(&parent_node->header); |
6702ed49 CM |
193 | |
194 | start_slot = 0; | |
195 | end_slot = parent_nritems; | |
196 | ||
197 | if (parent_nritems == 1) | |
198 | return 0; | |
199 | ||
200 | for (i = start_slot; i < end_slot; i++) { | |
201 | int close = 1; | |
202 | blocknr = btrfs_node_blockptr(parent_node, i); | |
e9d0b13b CM |
203 | if (last_block == 0) |
204 | last_block = blocknr; | |
6702ed49 CM |
205 | if (i > 0) { |
206 | other = btrfs_node_blockptr(parent_node, i - 1); | |
207 | close = close_blocks(blocknr, other); | |
208 | } | |
209 | if (close && i < end_slot - 1) { | |
210 | other = btrfs_node_blockptr(parent_node, i + 1); | |
211 | close = close_blocks(blocknr, other); | |
212 | } | |
e9d0b13b CM |
213 | if (close) { |
214 | last_block = blocknr; | |
6702ed49 | 215 | continue; |
e9d0b13b | 216 | } |
6702ed49 CM |
217 | |
218 | cur_bh = btrfs_find_tree_block(root, blocknr); | |
219 | if (!cur_bh || !buffer_uptodate(cur_bh) || | |
f2183bde | 220 | buffer_locked(cur_bh) || !buffer_defrag(cur_bh)) { |
6702ed49 CM |
221 | if (cache_only) { |
222 | brelse(cur_bh); | |
223 | continue; | |
224 | } | |
f2183bde CM |
225 | if (!cur_bh || !buffer_uptodate(cur_bh) || |
226 | buffer_locked(cur_bh)) { | |
227 | brelse(cur_bh); | |
228 | cur_bh = read_tree_block(root, blocknr); | |
229 | } | |
6702ed49 | 230 | } |
e9d0b13b CM |
231 | if (search_start == 0) |
232 | search_start = last_block & ~((u64)65535); | |
233 | ||
6702ed49 CM |
234 | err = __btrfs_cow_block(trans, root, cur_bh, parent, i, |
235 | &tmp_bh, search_start, | |
236 | min(8, end_slot - i)); | |
237 | if (err) | |
238 | break; | |
239 | search_start = bh_blocknr(tmp_bh); | |
f2183bde CM |
240 | *last_ret = search_start; |
241 | if (parent_level == 1) | |
242 | clear_buffer_defrag(tmp_bh); | |
6702ed49 CM |
243 | brelse(tmp_bh); |
244 | } | |
245 | return err; | |
246 | } | |
247 | ||
74123bd7 CM |
248 | /* |
249 | * The leaf data grows from end-to-front in the node. | |
250 | * this returns the address of the start of the last item, | |
251 | * which is the stop of the leaf data stack | |
252 | */ | |
123abc88 CM |
253 | static inline unsigned int leaf_data_end(struct btrfs_root *root, |
254 | struct btrfs_leaf *leaf) | |
be0e5c09 | 255 | { |
7518a238 | 256 | u32 nr = btrfs_header_nritems(&leaf->header); |
be0e5c09 | 257 | if (nr == 0) |
123abc88 | 258 | return BTRFS_LEAF_DATA_SIZE(root); |
0783fcfc | 259 | return btrfs_item_offset(leaf->items + nr - 1); |
be0e5c09 CM |
260 | } |
261 | ||
74123bd7 CM |
262 | /* |
263 | * compare two keys in a memcmp fashion | |
264 | */ | |
9aca1d51 | 265 | static int comp_keys(struct btrfs_disk_key *disk, struct btrfs_key *k2) |
be0e5c09 | 266 | { |
e2fa7227 CM |
267 | struct btrfs_key k1; |
268 | ||
269 | btrfs_disk_key_to_cpu(&k1, disk); | |
270 | ||
271 | if (k1.objectid > k2->objectid) | |
be0e5c09 | 272 | return 1; |
e2fa7227 | 273 | if (k1.objectid < k2->objectid) |
be0e5c09 | 274 | return -1; |
f254e52c CM |
275 | if (k1.flags > k2->flags) |
276 | return 1; | |
277 | if (k1.flags < k2->flags) | |
278 | return -1; | |
70b2befd CM |
279 | if (k1.offset > k2->offset) |
280 | return 1; | |
281 | if (k1.offset < k2->offset) | |
282 | return -1; | |
be0e5c09 CM |
283 | return 0; |
284 | } | |
74123bd7 | 285 | |
123abc88 CM |
286 | static int check_node(struct btrfs_root *root, struct btrfs_path *path, |
287 | int level) | |
aa5d6bed | 288 | { |
234b63a0 | 289 | struct btrfs_node *parent = NULL; |
e20d96d6 | 290 | struct btrfs_node *node = btrfs_buffer_node(path->nodes[level]); |
aa5d6bed | 291 | int parent_slot; |
8d7be552 CM |
292 | int slot; |
293 | struct btrfs_key cpukey; | |
7518a238 | 294 | u32 nritems = btrfs_header_nritems(&node->header); |
aa5d6bed CM |
295 | |
296 | if (path->nodes[level + 1]) | |
e20d96d6 | 297 | parent = btrfs_buffer_node(path->nodes[level + 1]); |
a1f39630 | 298 | |
8d7be552 | 299 | slot = path->slots[level]; |
7518a238 CM |
300 | BUG_ON(nritems == 0); |
301 | if (parent) { | |
e2fa7227 | 302 | struct btrfs_disk_key *parent_key; |
a1f39630 A |
303 | |
304 | parent_slot = path->slots[level + 1]; | |
123abc88 CM |
305 | parent_key = &parent->ptrs[parent_slot].key; |
306 | BUG_ON(memcmp(parent_key, &node->ptrs[0].key, | |
e2fa7227 | 307 | sizeof(struct btrfs_disk_key))); |
1d4f8a0c | 308 | BUG_ON(btrfs_node_blockptr(parent, parent_slot) != |
7518a238 | 309 | btrfs_header_blocknr(&node->header)); |
aa5d6bed | 310 | } |
123abc88 | 311 | BUG_ON(nritems > BTRFS_NODEPTRS_PER_BLOCK(root)); |
8d7be552 CM |
312 | if (slot != 0) { |
313 | btrfs_disk_key_to_cpu(&cpukey, &node->ptrs[slot - 1].key); | |
314 | BUG_ON(comp_keys(&node->ptrs[slot].key, &cpukey) <= 0); | |
315 | } | |
316 | if (slot < nritems - 1) { | |
317 | btrfs_disk_key_to_cpu(&cpukey, &node->ptrs[slot + 1].key); | |
318 | BUG_ON(comp_keys(&node->ptrs[slot].key, &cpukey) >= 0); | |
aa5d6bed CM |
319 | } |
320 | return 0; | |
321 | } | |
322 | ||
123abc88 CM |
323 | static int check_leaf(struct btrfs_root *root, struct btrfs_path *path, |
324 | int level) | |
aa5d6bed | 325 | { |
e20d96d6 | 326 | struct btrfs_leaf *leaf = btrfs_buffer_leaf(path->nodes[level]); |
234b63a0 | 327 | struct btrfs_node *parent = NULL; |
aa5d6bed | 328 | int parent_slot; |
8d7be552 CM |
329 | int slot = path->slots[0]; |
330 | struct btrfs_key cpukey; | |
331 | ||
7518a238 | 332 | u32 nritems = btrfs_header_nritems(&leaf->header); |
aa5d6bed CM |
333 | |
334 | if (path->nodes[level + 1]) | |
e20d96d6 | 335 | parent = btrfs_buffer_node(path->nodes[level + 1]); |
a1f39630 | 336 | |
123abc88 | 337 | BUG_ON(btrfs_leaf_free_space(root, leaf) < 0); |
7518a238 CM |
338 | |
339 | if (nritems == 0) | |
340 | return 0; | |
341 | ||
342 | if (parent) { | |
e2fa7227 | 343 | struct btrfs_disk_key *parent_key; |
a1f39630 A |
344 | |
345 | parent_slot = path->slots[level + 1]; | |
123abc88 | 346 | parent_key = &parent->ptrs[parent_slot].key; |
6702ed49 | 347 | |
aa5d6bed | 348 | BUG_ON(memcmp(parent_key, &leaf->items[0].key, |
e2fa7227 | 349 | sizeof(struct btrfs_disk_key))); |
1d4f8a0c | 350 | BUG_ON(btrfs_node_blockptr(parent, parent_slot) != |
7518a238 | 351 | btrfs_header_blocknr(&leaf->header)); |
aa5d6bed | 352 | } |
8d7be552 CM |
353 | if (slot != 0) { |
354 | btrfs_disk_key_to_cpu(&cpukey, &leaf->items[slot - 1].key); | |
355 | BUG_ON(comp_keys(&leaf->items[slot].key, &cpukey) <= 0); | |
356 | BUG_ON(btrfs_item_offset(leaf->items + slot - 1) != | |
357 | btrfs_item_end(leaf->items + slot)); | |
358 | } | |
359 | if (slot < nritems - 1) { | |
360 | btrfs_disk_key_to_cpu(&cpukey, &leaf->items[slot + 1].key); | |
361 | BUG_ON(comp_keys(&leaf->items[slot].key, &cpukey) >= 0); | |
362 | BUG_ON(btrfs_item_offset(leaf->items + slot) != | |
363 | btrfs_item_end(leaf->items + slot + 1)); | |
aa5d6bed | 364 | } |
8d7be552 CM |
365 | BUG_ON(btrfs_item_offset(leaf->items) + |
366 | btrfs_item_size(leaf->items) != BTRFS_LEAF_DATA_SIZE(root)); | |
aa5d6bed CM |
367 | return 0; |
368 | } | |
369 | ||
123abc88 CM |
370 | static int check_block(struct btrfs_root *root, struct btrfs_path *path, |
371 | int level) | |
aa5d6bed | 372 | { |
3eb0314d CM |
373 | struct btrfs_node *node = btrfs_buffer_node(path->nodes[level]); |
374 | if (memcmp(node->header.fsid, root->fs_info->disk_super->fsid, | |
375 | sizeof(node->header.fsid))) | |
376 | BUG(); | |
aa5d6bed | 377 | if (level == 0) |
123abc88 CM |
378 | return check_leaf(root, path, level); |
379 | return check_node(root, path, level); | |
aa5d6bed CM |
380 | } |
381 | ||
74123bd7 CM |
382 | /* |
383 | * search for key in the array p. items p are item_size apart | |
384 | * and there are 'max' items in p | |
385 | * the slot in the array is returned via slot, and it points to | |
386 | * the place where you would insert key if it is not found in | |
387 | * the array. | |
388 | * | |
389 | * slot may point to max if the key is bigger than all of the keys | |
390 | */ | |
9aca1d51 | 391 | static int generic_bin_search(char *p, int item_size, struct btrfs_key *key, |
be0e5c09 CM |
392 | int max, int *slot) |
393 | { | |
394 | int low = 0; | |
395 | int high = max; | |
396 | int mid; | |
397 | int ret; | |
e2fa7227 | 398 | struct btrfs_disk_key *tmp; |
be0e5c09 CM |
399 | |
400 | while(low < high) { | |
401 | mid = (low + high) / 2; | |
e2fa7227 | 402 | tmp = (struct btrfs_disk_key *)(p + mid * item_size); |
be0e5c09 CM |
403 | ret = comp_keys(tmp, key); |
404 | ||
405 | if (ret < 0) | |
406 | low = mid + 1; | |
407 | else if (ret > 0) | |
408 | high = mid; | |
409 | else { | |
410 | *slot = mid; | |
411 | return 0; | |
412 | } | |
413 | } | |
414 | *slot = low; | |
415 | return 1; | |
416 | } | |
417 | ||
97571fd0 CM |
418 | /* |
419 | * simple bin_search frontend that does the right thing for | |
420 | * leaves vs nodes | |
421 | */ | |
9aca1d51 | 422 | static int bin_search(struct btrfs_node *c, struct btrfs_key *key, int *slot) |
be0e5c09 | 423 | { |
7518a238 | 424 | if (btrfs_is_leaf(c)) { |
234b63a0 | 425 | struct btrfs_leaf *l = (struct btrfs_leaf *)c; |
0783fcfc CM |
426 | return generic_bin_search((void *)l->items, |
427 | sizeof(struct btrfs_item), | |
7518a238 CM |
428 | key, btrfs_header_nritems(&c->header), |
429 | slot); | |
be0e5c09 | 430 | } else { |
123abc88 CM |
431 | return generic_bin_search((void *)c->ptrs, |
432 | sizeof(struct btrfs_key_ptr), | |
7518a238 CM |
433 | key, btrfs_header_nritems(&c->header), |
434 | slot); | |
be0e5c09 CM |
435 | } |
436 | return -1; | |
437 | } | |
438 | ||
e20d96d6 CM |
439 | static struct buffer_head *read_node_slot(struct btrfs_root *root, |
440 | struct buffer_head *parent_buf, | |
bb803951 CM |
441 | int slot) |
442 | { | |
e20d96d6 | 443 | struct btrfs_node *node = btrfs_buffer_node(parent_buf); |
bb803951 CM |
444 | if (slot < 0) |
445 | return NULL; | |
7518a238 | 446 | if (slot >= btrfs_header_nritems(&node->header)) |
bb803951 | 447 | return NULL; |
1d4f8a0c | 448 | return read_tree_block(root, btrfs_node_blockptr(node, slot)); |
bb803951 CM |
449 | } |
450 | ||
e089f05c CM |
451 | static int balance_level(struct btrfs_trans_handle *trans, struct btrfs_root |
452 | *root, struct btrfs_path *path, int level) | |
bb803951 | 453 | { |
e20d96d6 CM |
454 | struct buffer_head *right_buf; |
455 | struct buffer_head *mid_buf; | |
456 | struct buffer_head *left_buf; | |
457 | struct buffer_head *parent_buf = NULL; | |
234b63a0 CM |
458 | struct btrfs_node *right = NULL; |
459 | struct btrfs_node *mid; | |
460 | struct btrfs_node *left = NULL; | |
461 | struct btrfs_node *parent = NULL; | |
bb803951 CM |
462 | int ret = 0; |
463 | int wret; | |
464 | int pslot; | |
bb803951 | 465 | int orig_slot = path->slots[level]; |
54aa1f4d | 466 | int err_on_enospc = 0; |
79f95c82 | 467 | u64 orig_ptr; |
bb803951 CM |
468 | |
469 | if (level == 0) | |
470 | return 0; | |
471 | ||
472 | mid_buf = path->nodes[level]; | |
e20d96d6 | 473 | mid = btrfs_buffer_node(mid_buf); |
1d4f8a0c | 474 | orig_ptr = btrfs_node_blockptr(mid, orig_slot); |
79f95c82 | 475 | |
234b63a0 | 476 | if (level < BTRFS_MAX_LEVEL - 1) |
bb803951 CM |
477 | parent_buf = path->nodes[level + 1]; |
478 | pslot = path->slots[level + 1]; | |
479 | ||
40689478 CM |
480 | /* |
481 | * deal with the case where there is only one pointer in the root | |
482 | * by promoting the node below to a root | |
483 | */ | |
bb803951 | 484 | if (!parent_buf) { |
e20d96d6 | 485 | struct buffer_head *child; |
7eccb903 | 486 | u64 blocknr = bh_blocknr(mid_buf); |
bb803951 | 487 | |
7518a238 | 488 | if (btrfs_header_nritems(&mid->header) != 1) |
bb803951 CM |
489 | return 0; |
490 | ||
491 | /* promote the child to a root */ | |
492 | child = read_node_slot(root, mid_buf, 0); | |
493 | BUG_ON(!child); | |
494 | root->node = child; | |
495 | path->nodes[level] = NULL; | |
d6025579 CM |
496 | clean_tree_block(trans, root, mid_buf); |
497 | wait_on_buffer(mid_buf); | |
bb803951 | 498 | /* once for the path */ |
234b63a0 | 499 | btrfs_block_release(root, mid_buf); |
bb803951 | 500 | /* once for the root ptr */ |
234b63a0 | 501 | btrfs_block_release(root, mid_buf); |
e089f05c | 502 | return btrfs_free_extent(trans, root, blocknr, 1, 1); |
bb803951 | 503 | } |
e20d96d6 | 504 | parent = btrfs_buffer_node(parent_buf); |
bb803951 | 505 | |
123abc88 CM |
506 | if (btrfs_header_nritems(&mid->header) > |
507 | BTRFS_NODEPTRS_PER_BLOCK(root) / 4) | |
bb803951 CM |
508 | return 0; |
509 | ||
54aa1f4d CM |
510 | if (btrfs_header_nritems(&mid->header) < 2) |
511 | err_on_enospc = 1; | |
512 | ||
bb803951 CM |
513 | left_buf = read_node_slot(root, parent_buf, pslot - 1); |
514 | right_buf = read_node_slot(root, parent_buf, pslot + 1); | |
79f95c82 CM |
515 | |
516 | /* first, try to make some room in the middle buffer */ | |
bb803951 | 517 | if (left_buf) { |
54aa1f4d CM |
518 | wret = btrfs_cow_block(trans, root, left_buf, |
519 | parent_buf, pslot - 1, &left_buf); | |
520 | if (wret) { | |
521 | ret = wret; | |
522 | goto enospc; | |
523 | } | |
e20d96d6 | 524 | left = btrfs_buffer_node(left_buf); |
7518a238 | 525 | orig_slot += btrfs_header_nritems(&left->header); |
e089f05c | 526 | wret = push_node_left(trans, root, left_buf, mid_buf); |
79f95c82 CM |
527 | if (wret < 0) |
528 | ret = wret; | |
54aa1f4d CM |
529 | if (btrfs_header_nritems(&mid->header) < 2) |
530 | err_on_enospc = 1; | |
bb803951 | 531 | } |
79f95c82 CM |
532 | |
533 | /* | |
534 | * then try to empty the right most buffer into the middle | |
535 | */ | |
bb803951 | 536 | if (right_buf) { |
54aa1f4d CM |
537 | wret = btrfs_cow_block(trans, root, right_buf, |
538 | parent_buf, pslot + 1, &right_buf); | |
539 | if (wret) { | |
540 | ret = wret; | |
541 | goto enospc; | |
542 | } | |
543 | ||
e20d96d6 | 544 | right = btrfs_buffer_node(right_buf); |
e089f05c | 545 | wret = push_node_left(trans, root, mid_buf, right_buf); |
54aa1f4d | 546 | if (wret < 0 && wret != -ENOSPC) |
79f95c82 | 547 | ret = wret; |
7518a238 | 548 | if (btrfs_header_nritems(&right->header) == 0) { |
7eccb903 | 549 | u64 blocknr = bh_blocknr(right_buf); |
e089f05c | 550 | clean_tree_block(trans, root, right_buf); |
d6025579 CM |
551 | wait_on_buffer(right_buf); |
552 | btrfs_block_release(root, right_buf); | |
bb803951 CM |
553 | right_buf = NULL; |
554 | right = NULL; | |
e089f05c CM |
555 | wret = del_ptr(trans, root, path, level + 1, pslot + |
556 | 1); | |
bb803951 CM |
557 | if (wret) |
558 | ret = wret; | |
e089f05c | 559 | wret = btrfs_free_extent(trans, root, blocknr, 1, 1); |
bb803951 CM |
560 | if (wret) |
561 | ret = wret; | |
562 | } else { | |
d6025579 CM |
563 | btrfs_memcpy(root, parent, |
564 | &parent->ptrs[pslot + 1].key, | |
565 | &right->ptrs[0].key, | |
566 | sizeof(struct btrfs_disk_key)); | |
567 | btrfs_mark_buffer_dirty(parent_buf); | |
bb803951 CM |
568 | } |
569 | } | |
7518a238 | 570 | if (btrfs_header_nritems(&mid->header) == 1) { |
79f95c82 CM |
571 | /* |
572 | * we're not allowed to leave a node with one item in the | |
573 | * tree during a delete. A deletion from lower in the tree | |
574 | * could try to delete the only pointer in this node. | |
575 | * So, pull some keys from the left. | |
576 | * There has to be a left pointer at this point because | |
577 | * otherwise we would have pulled some pointers from the | |
578 | * right | |
579 | */ | |
580 | BUG_ON(!left_buf); | |
e089f05c | 581 | wret = balance_node_right(trans, root, mid_buf, left_buf); |
54aa1f4d | 582 | if (wret < 0) { |
79f95c82 | 583 | ret = wret; |
54aa1f4d CM |
584 | goto enospc; |
585 | } | |
79f95c82 CM |
586 | BUG_ON(wret == 1); |
587 | } | |
7518a238 | 588 | if (btrfs_header_nritems(&mid->header) == 0) { |
79f95c82 | 589 | /* we've managed to empty the middle node, drop it */ |
7eccb903 | 590 | u64 blocknr = bh_blocknr(mid_buf); |
e089f05c | 591 | clean_tree_block(trans, root, mid_buf); |
d6025579 CM |
592 | wait_on_buffer(mid_buf); |
593 | btrfs_block_release(root, mid_buf); | |
bb803951 CM |
594 | mid_buf = NULL; |
595 | mid = NULL; | |
e089f05c | 596 | wret = del_ptr(trans, root, path, level + 1, pslot); |
bb803951 CM |
597 | if (wret) |
598 | ret = wret; | |
e089f05c | 599 | wret = btrfs_free_extent(trans, root, blocknr, 1, 1); |
bb803951 CM |
600 | if (wret) |
601 | ret = wret; | |
79f95c82 CM |
602 | } else { |
603 | /* update the parent key to reflect our changes */ | |
d6025579 CM |
604 | btrfs_memcpy(root, parent, |
605 | &parent->ptrs[pslot].key, &mid->ptrs[0].key, | |
606 | sizeof(struct btrfs_disk_key)); | |
607 | btrfs_mark_buffer_dirty(parent_buf); | |
79f95c82 | 608 | } |
bb803951 | 609 | |
79f95c82 | 610 | /* update the path */ |
bb803951 | 611 | if (left_buf) { |
7518a238 | 612 | if (btrfs_header_nritems(&left->header) > orig_slot) { |
e20d96d6 | 613 | get_bh(left_buf); |
bb803951 CM |
614 | path->nodes[level] = left_buf; |
615 | path->slots[level + 1] -= 1; | |
616 | path->slots[level] = orig_slot; | |
617 | if (mid_buf) | |
234b63a0 | 618 | btrfs_block_release(root, mid_buf); |
bb803951 | 619 | } else { |
7518a238 | 620 | orig_slot -= btrfs_header_nritems(&left->header); |
bb803951 CM |
621 | path->slots[level] = orig_slot; |
622 | } | |
623 | } | |
79f95c82 | 624 | /* double check we haven't messed things up */ |
123abc88 | 625 | check_block(root, path, level); |
e20d96d6 CM |
626 | if (orig_ptr != |
627 | btrfs_node_blockptr(btrfs_buffer_node(path->nodes[level]), | |
628 | path->slots[level])) | |
79f95c82 | 629 | BUG(); |
54aa1f4d | 630 | enospc: |
bb803951 | 631 | if (right_buf) |
234b63a0 | 632 | btrfs_block_release(root, right_buf); |
bb803951 | 633 | if (left_buf) |
234b63a0 | 634 | btrfs_block_release(root, left_buf); |
bb803951 CM |
635 | return ret; |
636 | } | |
637 | ||
e66f709b CM |
638 | /* returns zero if the push worked, non-zero otherwise */ |
639 | static int push_nodes_for_insert(struct btrfs_trans_handle *trans, | |
640 | struct btrfs_root *root, | |
641 | struct btrfs_path *path, int level) | |
642 | { | |
643 | struct buffer_head *right_buf; | |
644 | struct buffer_head *mid_buf; | |
645 | struct buffer_head *left_buf; | |
646 | struct buffer_head *parent_buf = NULL; | |
647 | struct btrfs_node *right = NULL; | |
648 | struct btrfs_node *mid; | |
649 | struct btrfs_node *left = NULL; | |
650 | struct btrfs_node *parent = NULL; | |
651 | int ret = 0; | |
652 | int wret; | |
653 | int pslot; | |
654 | int orig_slot = path->slots[level]; | |
655 | u64 orig_ptr; | |
656 | ||
657 | if (level == 0) | |
658 | return 1; | |
659 | ||
660 | mid_buf = path->nodes[level]; | |
661 | mid = btrfs_buffer_node(mid_buf); | |
662 | orig_ptr = btrfs_node_blockptr(mid, orig_slot); | |
663 | ||
664 | if (level < BTRFS_MAX_LEVEL - 1) | |
665 | parent_buf = path->nodes[level + 1]; | |
666 | pslot = path->slots[level + 1]; | |
667 | ||
668 | if (!parent_buf) | |
669 | return 1; | |
670 | parent = btrfs_buffer_node(parent_buf); | |
671 | ||
672 | left_buf = read_node_slot(root, parent_buf, pslot - 1); | |
673 | ||
674 | /* first, try to make some room in the middle buffer */ | |
675 | if (left_buf) { | |
676 | u32 left_nr; | |
e66f709b CM |
677 | left = btrfs_buffer_node(left_buf); |
678 | left_nr = btrfs_header_nritems(&left->header); | |
33ade1f8 CM |
679 | if (left_nr >= BTRFS_NODEPTRS_PER_BLOCK(root) - 1) { |
680 | wret = 1; | |
681 | } else { | |
54aa1f4d CM |
682 | ret = btrfs_cow_block(trans, root, left_buf, parent_buf, |
683 | pslot - 1, &left_buf); | |
684 | if (ret) | |
685 | wret = 1; | |
686 | else { | |
687 | left = btrfs_buffer_node(left_buf); | |
688 | wret = push_node_left(trans, root, | |
689 | left_buf, mid_buf); | |
690 | } | |
33ade1f8 | 691 | } |
e66f709b CM |
692 | if (wret < 0) |
693 | ret = wret; | |
694 | if (wret == 0) { | |
695 | orig_slot += left_nr; | |
696 | btrfs_memcpy(root, parent, | |
697 | &parent->ptrs[pslot].key, | |
698 | &mid->ptrs[0].key, | |
699 | sizeof(struct btrfs_disk_key)); | |
700 | btrfs_mark_buffer_dirty(parent_buf); | |
701 | if (btrfs_header_nritems(&left->header) > orig_slot) { | |
702 | path->nodes[level] = left_buf; | |
703 | path->slots[level + 1] -= 1; | |
704 | path->slots[level] = orig_slot; | |
705 | btrfs_block_release(root, mid_buf); | |
706 | } else { | |
707 | orig_slot -= | |
708 | btrfs_header_nritems(&left->header); | |
709 | path->slots[level] = orig_slot; | |
710 | btrfs_block_release(root, left_buf); | |
711 | } | |
712 | check_node(root, path, level); | |
713 | return 0; | |
714 | } | |
715 | btrfs_block_release(root, left_buf); | |
716 | } | |
717 | right_buf = read_node_slot(root, parent_buf, pslot + 1); | |
718 | ||
719 | /* | |
720 | * then try to empty the right most buffer into the middle | |
721 | */ | |
722 | if (right_buf) { | |
33ade1f8 | 723 | u32 right_nr; |
e66f709b | 724 | right = btrfs_buffer_node(right_buf); |
33ade1f8 CM |
725 | right_nr = btrfs_header_nritems(&right->header); |
726 | if (right_nr >= BTRFS_NODEPTRS_PER_BLOCK(root) - 1) { | |
727 | wret = 1; | |
728 | } else { | |
54aa1f4d CM |
729 | ret = btrfs_cow_block(trans, root, right_buf, |
730 | parent_buf, pslot + 1, | |
731 | &right_buf); | |
732 | if (ret) | |
733 | wret = 1; | |
734 | else { | |
735 | right = btrfs_buffer_node(right_buf); | |
736 | wret = balance_node_right(trans, root, | |
737 | right_buf, mid_buf); | |
738 | } | |
33ade1f8 | 739 | } |
e66f709b CM |
740 | if (wret < 0) |
741 | ret = wret; | |
742 | if (wret == 0) { | |
743 | btrfs_memcpy(root, parent, | |
744 | &parent->ptrs[pslot + 1].key, | |
745 | &right->ptrs[0].key, | |
746 | sizeof(struct btrfs_disk_key)); | |
747 | btrfs_mark_buffer_dirty(parent_buf); | |
748 | if (btrfs_header_nritems(&mid->header) <= orig_slot) { | |
749 | path->nodes[level] = right_buf; | |
750 | path->slots[level + 1] += 1; | |
751 | path->slots[level] = orig_slot - | |
752 | btrfs_header_nritems(&mid->header); | |
753 | btrfs_block_release(root, mid_buf); | |
754 | } else { | |
755 | btrfs_block_release(root, right_buf); | |
756 | } | |
757 | check_node(root, path, level); | |
758 | return 0; | |
759 | } | |
760 | btrfs_block_release(root, right_buf); | |
761 | } | |
762 | check_node(root, path, level); | |
763 | return 1; | |
764 | } | |
765 | ||
3c69faec CM |
766 | /* |
767 | * readahead one full node of leaves | |
768 | */ | |
769 | static void reada_for_search(struct btrfs_root *root, struct btrfs_path *path, | |
6702ed49 | 770 | int level, int slot) |
3c69faec CM |
771 | { |
772 | struct btrfs_node *node; | |
773 | int i; | |
774 | u32 nritems; | |
775 | u64 item_objectid; | |
776 | u64 blocknr; | |
777 | u64 search; | |
778 | u64 cluster_start; | |
779 | int ret; | |
780 | int nread = 0; | |
781 | int direction = path->reada; | |
782 | struct radix_tree_root found; | |
783 | unsigned long gang[8]; | |
784 | struct buffer_head *bh; | |
785 | ||
6702ed49 CM |
786 | if (level == 0) |
787 | return; | |
788 | ||
789 | if (!path->nodes[level]) | |
3c69faec CM |
790 | return; |
791 | ||
6702ed49 | 792 | node = btrfs_buffer_node(path->nodes[level]); |
3c69faec CM |
793 | search = btrfs_node_blockptr(node, slot); |
794 | bh = btrfs_find_tree_block(root, search); | |
795 | if (bh) { | |
796 | brelse(bh); | |
797 | return; | |
798 | } | |
799 | ||
800 | init_bit_radix(&found); | |
801 | nritems = btrfs_header_nritems(&node->header); | |
802 | for (i = slot; i < nritems; i++) { | |
803 | item_objectid = btrfs_disk_key_objectid(&node->ptrs[i].key); | |
804 | blocknr = btrfs_node_blockptr(node, i); | |
805 | set_radix_bit(&found, blocknr); | |
806 | } | |
807 | if (direction > 0) { | |
808 | cluster_start = search - 4; | |
809 | if (cluster_start > search) | |
810 | cluster_start = 0; | |
811 | } else | |
812 | cluster_start = search + 4; | |
813 | while(1) { | |
814 | ret = find_first_radix_bit(&found, gang, 0, ARRAY_SIZE(gang)); | |
815 | if (!ret) | |
816 | break; | |
817 | for (i = 0; i < ret; i++) { | |
818 | blocknr = gang[i]; | |
819 | clear_radix_bit(&found, blocknr); | |
6702ed49 | 820 | if (nread > 32) |
3c69faec | 821 | continue; |
f2183bde | 822 | if (close_blocks(cluster_start, blocknr)) { |
3c69faec CM |
823 | readahead_tree_block(root, blocknr); |
824 | nread++; | |
3c69faec | 825 | cluster_start = blocknr; |
3c69faec CM |
826 | } |
827 | } | |
828 | } | |
829 | } | |
74123bd7 CM |
830 | /* |
831 | * look for key in the tree. path is filled in with nodes along the way | |
832 | * if key is found, we return zero and you can find the item in the leaf | |
833 | * level of the path (level 0) | |
834 | * | |
835 | * If the key isn't found, the path points to the slot where it should | |
aa5d6bed CM |
836 | * be inserted, and 1 is returned. If there are other errors during the |
837 | * search a negative error number is returned. | |
97571fd0 CM |
838 | * |
839 | * if ins_len > 0, nodes and leaves will be split as we walk down the | |
840 | * tree. if ins_len < 0, nodes will be merged as we walk down the tree (if | |
841 | * possible) | |
74123bd7 | 842 | */ |
e089f05c CM |
843 | int btrfs_search_slot(struct btrfs_trans_handle *trans, struct btrfs_root |
844 | *root, struct btrfs_key *key, struct btrfs_path *p, int | |
845 | ins_len, int cow) | |
be0e5c09 | 846 | { |
e20d96d6 CM |
847 | struct buffer_head *b; |
848 | struct buffer_head *cow_buf; | |
234b63a0 | 849 | struct btrfs_node *c; |
3c69faec | 850 | u64 blocknr; |
be0e5c09 CM |
851 | int slot; |
852 | int ret; | |
853 | int level; | |
3c69faec | 854 | int should_reada = p->reada; |
9f3a7427 CM |
855 | u8 lowest_level = 0; |
856 | ||
6702ed49 CM |
857 | lowest_level = p->lowest_level; |
858 | WARN_ON(lowest_level && ins_len); | |
22b0ebda CM |
859 | WARN_ON(p->nodes[0] != NULL); |
860 | WARN_ON(!mutex_is_locked(&root->fs_info->fs_mutex)); | |
bb803951 CM |
861 | again: |
862 | b = root->node; | |
e20d96d6 | 863 | get_bh(b); |
eb60ceac | 864 | while (b) { |
e20d96d6 CM |
865 | c = btrfs_buffer_node(b); |
866 | level = btrfs_header_level(&c->header); | |
02217ed2 CM |
867 | if (cow) { |
868 | int wret; | |
e20d96d6 CM |
869 | wret = btrfs_cow_block(trans, root, b, |
870 | p->nodes[level + 1], | |
871 | p->slots[level + 1], | |
e089f05c | 872 | &cow_buf); |
54aa1f4d CM |
873 | if (wret) { |
874 | btrfs_block_release(root, cow_buf); | |
875 | return wret; | |
876 | } | |
02217ed2 | 877 | b = cow_buf; |
2c90e5d6 | 878 | c = btrfs_buffer_node(b); |
02217ed2 CM |
879 | } |
880 | BUG_ON(!cow && ins_len); | |
2c90e5d6 CM |
881 | if (level != btrfs_header_level(&c->header)) |
882 | WARN_ON(1); | |
883 | level = btrfs_header_level(&c->header); | |
eb60ceac | 884 | p->nodes[level] = b; |
123abc88 | 885 | ret = check_block(root, p, level); |
aa5d6bed CM |
886 | if (ret) |
887 | return -1; | |
be0e5c09 | 888 | ret = bin_search(c, key, &slot); |
7518a238 | 889 | if (!btrfs_is_leaf(c)) { |
be0e5c09 CM |
890 | if (ret && slot > 0) |
891 | slot -= 1; | |
892 | p->slots[level] = slot; | |
d4dbff95 CM |
893 | if (ins_len > 0 && btrfs_header_nritems(&c->header) >= |
894 | BTRFS_NODEPTRS_PER_BLOCK(root) - 1) { | |
e089f05c | 895 | int sret = split_node(trans, root, p, level); |
5c680ed6 CM |
896 | BUG_ON(sret > 0); |
897 | if (sret) | |
898 | return sret; | |
899 | b = p->nodes[level]; | |
e20d96d6 | 900 | c = btrfs_buffer_node(b); |
5c680ed6 | 901 | slot = p->slots[level]; |
bb803951 | 902 | } else if (ins_len < 0) { |
e089f05c CM |
903 | int sret = balance_level(trans, root, p, |
904 | level); | |
bb803951 CM |
905 | if (sret) |
906 | return sret; | |
907 | b = p->nodes[level]; | |
908 | if (!b) | |
909 | goto again; | |
e20d96d6 | 910 | c = btrfs_buffer_node(b); |
bb803951 | 911 | slot = p->slots[level]; |
7518a238 | 912 | BUG_ON(btrfs_header_nritems(&c->header) == 1); |
5c680ed6 | 913 | } |
9f3a7427 CM |
914 | /* this is only true while dropping a snapshot */ |
915 | if (level == lowest_level) | |
916 | break; | |
3c69faec | 917 | blocknr = btrfs_node_blockptr(c, slot); |
6702ed49 CM |
918 | if (should_reada) |
919 | reada_for_search(root, p, level, slot); | |
1d4f8a0c | 920 | b = read_tree_block(root, btrfs_node_blockptr(c, slot)); |
3c69faec | 921 | |
be0e5c09 | 922 | } else { |
234b63a0 | 923 | struct btrfs_leaf *l = (struct btrfs_leaf *)c; |
be0e5c09 | 924 | p->slots[level] = slot; |
123abc88 | 925 | if (ins_len > 0 && btrfs_leaf_free_space(root, l) < |
0783fcfc | 926 | sizeof(struct btrfs_item) + ins_len) { |
d4dbff95 CM |
927 | int sret = split_leaf(trans, root, key, |
928 | p, ins_len); | |
5c680ed6 CM |
929 | BUG_ON(sret > 0); |
930 | if (sret) | |
931 | return sret; | |
932 | } | |
be0e5c09 CM |
933 | return ret; |
934 | } | |
935 | } | |
aa5d6bed | 936 | return 1; |
be0e5c09 CM |
937 | } |
938 | ||
74123bd7 CM |
939 | /* |
940 | * adjust the pointers going up the tree, starting at level | |
941 | * making sure the right key of each node is points to 'key'. | |
942 | * This is used after shifting pointers to the left, so it stops | |
943 | * fixing up pointers when a given leaf/node is not in slot 0 of the | |
944 | * higher levels | |
aa5d6bed CM |
945 | * |
946 | * If this fails to write a tree block, it returns -1, but continues | |
947 | * fixing up the blocks in ram so the tree is consistent. | |
74123bd7 | 948 | */ |
e089f05c CM |
949 | static int fixup_low_keys(struct btrfs_trans_handle *trans, struct btrfs_root |
950 | *root, struct btrfs_path *path, struct btrfs_disk_key | |
951 | *key, int level) | |
be0e5c09 CM |
952 | { |
953 | int i; | |
aa5d6bed | 954 | int ret = 0; |
234b63a0 CM |
955 | for (i = level; i < BTRFS_MAX_LEVEL; i++) { |
956 | struct btrfs_node *t; | |
be0e5c09 | 957 | int tslot = path->slots[i]; |
eb60ceac | 958 | if (!path->nodes[i]) |
be0e5c09 | 959 | break; |
e20d96d6 | 960 | t = btrfs_buffer_node(path->nodes[i]); |
d6025579 CM |
961 | btrfs_memcpy(root, t, &t->ptrs[tslot].key, key, sizeof(*key)); |
962 | btrfs_mark_buffer_dirty(path->nodes[i]); | |
be0e5c09 CM |
963 | if (tslot != 0) |
964 | break; | |
965 | } | |
aa5d6bed | 966 | return ret; |
be0e5c09 CM |
967 | } |
968 | ||
74123bd7 CM |
969 | /* |
970 | * try to push data from one node into the next node left in the | |
79f95c82 | 971 | * tree. |
aa5d6bed CM |
972 | * |
973 | * returns 0 if some ptrs were pushed left, < 0 if there was some horrible | |
974 | * error, and > 0 if there was no room in the left hand block. | |
74123bd7 | 975 | */ |
e089f05c | 976 | static int push_node_left(struct btrfs_trans_handle *trans, struct btrfs_root |
e20d96d6 CM |
977 | *root, struct buffer_head *dst_buf, struct |
978 | buffer_head *src_buf) | |
be0e5c09 | 979 | { |
e20d96d6 CM |
980 | struct btrfs_node *src = btrfs_buffer_node(src_buf); |
981 | struct btrfs_node *dst = btrfs_buffer_node(dst_buf); | |
be0e5c09 | 982 | int push_items = 0; |
bb803951 CM |
983 | int src_nritems; |
984 | int dst_nritems; | |
aa5d6bed | 985 | int ret = 0; |
be0e5c09 | 986 | |
7518a238 CM |
987 | src_nritems = btrfs_header_nritems(&src->header); |
988 | dst_nritems = btrfs_header_nritems(&dst->header); | |
123abc88 | 989 | push_items = BTRFS_NODEPTRS_PER_BLOCK(root) - dst_nritems; |
54aa1f4d | 990 | |
eb60ceac | 991 | if (push_items <= 0) { |
be0e5c09 | 992 | return 1; |
eb60ceac | 993 | } |
be0e5c09 | 994 | |
bb803951 | 995 | if (src_nritems < push_items) |
79f95c82 CM |
996 | push_items = src_nritems; |
997 | ||
d6025579 CM |
998 | btrfs_memcpy(root, dst, dst->ptrs + dst_nritems, src->ptrs, |
999 | push_items * sizeof(struct btrfs_key_ptr)); | |
bb803951 | 1000 | if (push_items < src_nritems) { |
d6025579 | 1001 | btrfs_memmove(root, src, src->ptrs, src->ptrs + push_items, |
e2fa7227 | 1002 | (src_nritems - push_items) * |
123abc88 | 1003 | sizeof(struct btrfs_key_ptr)); |
bb803951 | 1004 | } |
7518a238 CM |
1005 | btrfs_set_header_nritems(&src->header, src_nritems - push_items); |
1006 | btrfs_set_header_nritems(&dst->header, dst_nritems + push_items); | |
d6025579 CM |
1007 | btrfs_mark_buffer_dirty(src_buf); |
1008 | btrfs_mark_buffer_dirty(dst_buf); | |
79f95c82 CM |
1009 | return ret; |
1010 | } | |
1011 | ||
1012 | /* | |
1013 | * try to push data from one node into the next node right in the | |
1014 | * tree. | |
1015 | * | |
1016 | * returns 0 if some ptrs were pushed, < 0 if there was some horrible | |
1017 | * error, and > 0 if there was no room in the right hand block. | |
1018 | * | |
1019 | * this will only push up to 1/2 the contents of the left node over | |
1020 | */ | |
e089f05c | 1021 | static int balance_node_right(struct btrfs_trans_handle *trans, struct |
e20d96d6 CM |
1022 | btrfs_root *root, struct buffer_head *dst_buf, |
1023 | struct buffer_head *src_buf) | |
79f95c82 | 1024 | { |
e20d96d6 CM |
1025 | struct btrfs_node *src = btrfs_buffer_node(src_buf); |
1026 | struct btrfs_node *dst = btrfs_buffer_node(dst_buf); | |
79f95c82 CM |
1027 | int push_items = 0; |
1028 | int max_push; | |
1029 | int src_nritems; | |
1030 | int dst_nritems; | |
1031 | int ret = 0; | |
79f95c82 | 1032 | |
7518a238 CM |
1033 | src_nritems = btrfs_header_nritems(&src->header); |
1034 | dst_nritems = btrfs_header_nritems(&dst->header); | |
123abc88 | 1035 | push_items = BTRFS_NODEPTRS_PER_BLOCK(root) - dst_nritems; |
79f95c82 CM |
1036 | if (push_items <= 0) { |
1037 | return 1; | |
1038 | } | |
1039 | ||
1040 | max_push = src_nritems / 2 + 1; | |
1041 | /* don't try to empty the node */ | |
1042 | if (max_push > src_nritems) | |
1043 | return 1; | |
1044 | if (max_push < push_items) | |
1045 | push_items = max_push; | |
1046 | ||
d6025579 CM |
1047 | btrfs_memmove(root, dst, dst->ptrs + push_items, dst->ptrs, |
1048 | dst_nritems * sizeof(struct btrfs_key_ptr)); | |
1049 | ||
1050 | btrfs_memcpy(root, dst, dst->ptrs, | |
1051 | src->ptrs + src_nritems - push_items, | |
1052 | push_items * sizeof(struct btrfs_key_ptr)); | |
79f95c82 | 1053 | |
7518a238 CM |
1054 | btrfs_set_header_nritems(&src->header, src_nritems - push_items); |
1055 | btrfs_set_header_nritems(&dst->header, dst_nritems + push_items); | |
79f95c82 | 1056 | |
d6025579 CM |
1057 | btrfs_mark_buffer_dirty(src_buf); |
1058 | btrfs_mark_buffer_dirty(dst_buf); | |
aa5d6bed | 1059 | return ret; |
be0e5c09 CM |
1060 | } |
1061 | ||
97571fd0 CM |
1062 | /* |
1063 | * helper function to insert a new root level in the tree. | |
1064 | * A new node is allocated, and a single item is inserted to | |
1065 | * point to the existing root | |
aa5d6bed CM |
1066 | * |
1067 | * returns zero on success or < 0 on failure. | |
97571fd0 | 1068 | */ |
e089f05c CM |
1069 | static int insert_new_root(struct btrfs_trans_handle *trans, struct btrfs_root |
1070 | *root, struct btrfs_path *path, int level) | |
5c680ed6 | 1071 | { |
e20d96d6 | 1072 | struct buffer_head *t; |
234b63a0 CM |
1073 | struct btrfs_node *lower; |
1074 | struct btrfs_node *c; | |
e2fa7227 | 1075 | struct btrfs_disk_key *lower_key; |
5c680ed6 CM |
1076 | |
1077 | BUG_ON(path->nodes[level]); | |
1078 | BUG_ON(path->nodes[level-1] != root->node); | |
1079 | ||
6702ed49 | 1080 | t = btrfs_alloc_free_block(trans, root, root->node->b_blocknr, 0); |
54aa1f4d CM |
1081 | if (IS_ERR(t)) |
1082 | return PTR_ERR(t); | |
e20d96d6 | 1083 | c = btrfs_buffer_node(t); |
123abc88 | 1084 | memset(c, 0, root->blocksize); |
7518a238 CM |
1085 | btrfs_set_header_nritems(&c->header, 1); |
1086 | btrfs_set_header_level(&c->header, level); | |
7eccb903 | 1087 | btrfs_set_header_blocknr(&c->header, bh_blocknr(t)); |
7f5c1516 | 1088 | btrfs_set_header_generation(&c->header, trans->transid); |
4d775673 | 1089 | btrfs_set_header_owner(&c->header, root->root_key.objectid); |
e20d96d6 | 1090 | lower = btrfs_buffer_node(path->nodes[level-1]); |
3eb0314d CM |
1091 | memcpy(c->header.fsid, root->fs_info->disk_super->fsid, |
1092 | sizeof(c->header.fsid)); | |
7518a238 | 1093 | if (btrfs_is_leaf(lower)) |
234b63a0 | 1094 | lower_key = &((struct btrfs_leaf *)lower)->items[0].key; |
5c680ed6 | 1095 | else |
123abc88 | 1096 | lower_key = &lower->ptrs[0].key; |
d6025579 CM |
1097 | btrfs_memcpy(root, c, &c->ptrs[0].key, lower_key, |
1098 | sizeof(struct btrfs_disk_key)); | |
7eccb903 | 1099 | btrfs_set_node_blockptr(c, 0, bh_blocknr(path->nodes[level - 1])); |
d5719762 | 1100 | |
d6025579 | 1101 | btrfs_mark_buffer_dirty(t); |
d5719762 | 1102 | |
5c680ed6 | 1103 | /* the super has an extra ref to root->node */ |
234b63a0 | 1104 | btrfs_block_release(root, root->node); |
5c680ed6 | 1105 | root->node = t; |
e20d96d6 | 1106 | get_bh(t); |
5c680ed6 CM |
1107 | path->nodes[level] = t; |
1108 | path->slots[level] = 0; | |
1109 | return 0; | |
1110 | } | |
1111 | ||
74123bd7 CM |
1112 | /* |
1113 | * worker function to insert a single pointer in a node. | |
1114 | * the node should have enough room for the pointer already | |
97571fd0 | 1115 | * |
74123bd7 CM |
1116 | * slot and level indicate where you want the key to go, and |
1117 | * blocknr is the block the key points to. | |
aa5d6bed CM |
1118 | * |
1119 | * returns zero on success and < 0 on any error | |
74123bd7 | 1120 | */ |
e089f05c CM |
1121 | static int insert_ptr(struct btrfs_trans_handle *trans, struct btrfs_root |
1122 | *root, struct btrfs_path *path, struct btrfs_disk_key | |
1123 | *key, u64 blocknr, int slot, int level) | |
74123bd7 | 1124 | { |
234b63a0 | 1125 | struct btrfs_node *lower; |
74123bd7 | 1126 | int nritems; |
5c680ed6 CM |
1127 | |
1128 | BUG_ON(!path->nodes[level]); | |
e20d96d6 | 1129 | lower = btrfs_buffer_node(path->nodes[level]); |
7518a238 | 1130 | nritems = btrfs_header_nritems(&lower->header); |
74123bd7 CM |
1131 | if (slot > nritems) |
1132 | BUG(); | |
123abc88 | 1133 | if (nritems == BTRFS_NODEPTRS_PER_BLOCK(root)) |
74123bd7 CM |
1134 | BUG(); |
1135 | if (slot != nritems) { | |
d6025579 CM |
1136 | btrfs_memmove(root, lower, lower->ptrs + slot + 1, |
1137 | lower->ptrs + slot, | |
1138 | (nritems - slot) * sizeof(struct btrfs_key_ptr)); | |
74123bd7 | 1139 | } |
d6025579 CM |
1140 | btrfs_memcpy(root, lower, &lower->ptrs[slot].key, |
1141 | key, sizeof(struct btrfs_disk_key)); | |
1d4f8a0c | 1142 | btrfs_set_node_blockptr(lower, slot, blocknr); |
7518a238 | 1143 | btrfs_set_header_nritems(&lower->header, nritems + 1); |
d6025579 | 1144 | btrfs_mark_buffer_dirty(path->nodes[level]); |
098f59c2 | 1145 | check_node(root, path, level); |
74123bd7 CM |
1146 | return 0; |
1147 | } | |
1148 | ||
97571fd0 CM |
1149 | /* |
1150 | * split the node at the specified level in path in two. | |
1151 | * The path is corrected to point to the appropriate node after the split | |
1152 | * | |
1153 | * Before splitting this tries to make some room in the node by pushing | |
1154 | * left and right, if either one works, it returns right away. | |
aa5d6bed CM |
1155 | * |
1156 | * returns 0 on success and < 0 on failure | |
97571fd0 | 1157 | */ |
e089f05c CM |
1158 | static int split_node(struct btrfs_trans_handle *trans, struct btrfs_root |
1159 | *root, struct btrfs_path *path, int level) | |
be0e5c09 | 1160 | { |
e20d96d6 | 1161 | struct buffer_head *t; |
234b63a0 | 1162 | struct btrfs_node *c; |
e20d96d6 | 1163 | struct buffer_head *split_buffer; |
234b63a0 | 1164 | struct btrfs_node *split; |
be0e5c09 | 1165 | int mid; |
5c680ed6 | 1166 | int ret; |
aa5d6bed | 1167 | int wret; |
7518a238 | 1168 | u32 c_nritems; |
eb60ceac | 1169 | |
5c680ed6 | 1170 | t = path->nodes[level]; |
e20d96d6 | 1171 | c = btrfs_buffer_node(t); |
5c680ed6 CM |
1172 | if (t == root->node) { |
1173 | /* trying to split the root, lets make a new one */ | |
e089f05c | 1174 | ret = insert_new_root(trans, root, path, level + 1); |
5c680ed6 CM |
1175 | if (ret) |
1176 | return ret; | |
e66f709b CM |
1177 | } else { |
1178 | ret = push_nodes_for_insert(trans, root, path, level); | |
1179 | t = path->nodes[level]; | |
1180 | c = btrfs_buffer_node(t); | |
1181 | if (!ret && | |
1182 | btrfs_header_nritems(&c->header) < | |
1183 | BTRFS_NODEPTRS_PER_BLOCK(root) - 1) | |
1184 | return 0; | |
54aa1f4d CM |
1185 | if (ret < 0) |
1186 | return ret; | |
be0e5c09 | 1187 | } |
e66f709b | 1188 | |
7518a238 | 1189 | c_nritems = btrfs_header_nritems(&c->header); |
6702ed49 | 1190 | split_buffer = btrfs_alloc_free_block(trans, root, t->b_blocknr, 0); |
54aa1f4d CM |
1191 | if (IS_ERR(split_buffer)) |
1192 | return PTR_ERR(split_buffer); | |
1193 | ||
e20d96d6 | 1194 | split = btrfs_buffer_node(split_buffer); |
7518a238 | 1195 | btrfs_set_header_flags(&split->header, btrfs_header_flags(&c->header)); |
9a6f11ed | 1196 | btrfs_set_header_level(&split->header, btrfs_header_level(&c->header)); |
7eccb903 | 1197 | btrfs_set_header_blocknr(&split->header, bh_blocknr(split_buffer)); |
7f5c1516 | 1198 | btrfs_set_header_generation(&split->header, trans->transid); |
4d775673 | 1199 | btrfs_set_header_owner(&split->header, root->root_key.objectid); |
3eb0314d CM |
1200 | memcpy(split->header.fsid, root->fs_info->disk_super->fsid, |
1201 | sizeof(split->header.fsid)); | |
7518a238 | 1202 | mid = (c_nritems + 1) / 2; |
d6025579 CM |
1203 | btrfs_memcpy(root, split, split->ptrs, c->ptrs + mid, |
1204 | (c_nritems - mid) * sizeof(struct btrfs_key_ptr)); | |
7518a238 CM |
1205 | btrfs_set_header_nritems(&split->header, c_nritems - mid); |
1206 | btrfs_set_header_nritems(&c->header, mid); | |
aa5d6bed CM |
1207 | ret = 0; |
1208 | ||
d6025579 CM |
1209 | btrfs_mark_buffer_dirty(t); |
1210 | btrfs_mark_buffer_dirty(split_buffer); | |
e089f05c | 1211 | wret = insert_ptr(trans, root, path, &split->ptrs[0].key, |
7eccb903 | 1212 | bh_blocknr(split_buffer), path->slots[level + 1] + 1, |
123abc88 | 1213 | level + 1); |
aa5d6bed CM |
1214 | if (wret) |
1215 | ret = wret; | |
1216 | ||
5de08d7d | 1217 | if (path->slots[level] >= mid) { |
5c680ed6 | 1218 | path->slots[level] -= mid; |
234b63a0 | 1219 | btrfs_block_release(root, t); |
5c680ed6 CM |
1220 | path->nodes[level] = split_buffer; |
1221 | path->slots[level + 1] += 1; | |
1222 | } else { | |
234b63a0 | 1223 | btrfs_block_release(root, split_buffer); |
be0e5c09 | 1224 | } |
aa5d6bed | 1225 | return ret; |
be0e5c09 CM |
1226 | } |
1227 | ||
74123bd7 CM |
1228 | /* |
1229 | * how many bytes are required to store the items in a leaf. start | |
1230 | * and nr indicate which items in the leaf to check. This totals up the | |
1231 | * space used both by the item structs and the item data | |
1232 | */ | |
234b63a0 | 1233 | static int leaf_space_used(struct btrfs_leaf *l, int start, int nr) |
be0e5c09 CM |
1234 | { |
1235 | int data_len; | |
d4dbff95 CM |
1236 | int nritems = btrfs_header_nritems(&l->header); |
1237 | int end = min(nritems, start + nr) - 1; | |
be0e5c09 CM |
1238 | |
1239 | if (!nr) | |
1240 | return 0; | |
0783fcfc CM |
1241 | data_len = btrfs_item_end(l->items + start); |
1242 | data_len = data_len - btrfs_item_offset(l->items + end); | |
1243 | data_len += sizeof(struct btrfs_item) * nr; | |
d4dbff95 | 1244 | WARN_ON(data_len < 0); |
be0e5c09 CM |
1245 | return data_len; |
1246 | } | |
1247 | ||
d4dbff95 CM |
1248 | /* |
1249 | * The space between the end of the leaf items and | |
1250 | * the start of the leaf data. IOW, how much room | |
1251 | * the leaf has left for both items and data | |
1252 | */ | |
1253 | int btrfs_leaf_free_space(struct btrfs_root *root, struct btrfs_leaf *leaf) | |
1254 | { | |
1255 | int nritems = btrfs_header_nritems(&leaf->header); | |
1256 | return BTRFS_LEAF_DATA_SIZE(root) - leaf_space_used(leaf, 0, nritems); | |
1257 | } | |
1258 | ||
00ec4c51 CM |
1259 | /* |
1260 | * push some data in the path leaf to the right, trying to free up at | |
1261 | * least data_size bytes. returns zero if the push worked, nonzero otherwise | |
aa5d6bed CM |
1262 | * |
1263 | * returns 1 if the push failed because the other node didn't have enough | |
1264 | * room, 0 if everything worked out and < 0 if there were major errors. | |
00ec4c51 | 1265 | */ |
e089f05c CM |
1266 | static int push_leaf_right(struct btrfs_trans_handle *trans, struct btrfs_root |
1267 | *root, struct btrfs_path *path, int data_size) | |
00ec4c51 | 1268 | { |
e20d96d6 CM |
1269 | struct buffer_head *left_buf = path->nodes[0]; |
1270 | struct btrfs_leaf *left = btrfs_buffer_leaf(left_buf); | |
234b63a0 | 1271 | struct btrfs_leaf *right; |
e20d96d6 CM |
1272 | struct buffer_head *right_buf; |
1273 | struct buffer_head *upper; | |
1274 | struct btrfs_node *upper_node; | |
00ec4c51 CM |
1275 | int slot; |
1276 | int i; | |
1277 | int free_space; | |
1278 | int push_space = 0; | |
1279 | int push_items = 0; | |
0783fcfc | 1280 | struct btrfs_item *item; |
7518a238 CM |
1281 | u32 left_nritems; |
1282 | u32 right_nritems; | |
54aa1f4d | 1283 | int ret; |
00ec4c51 CM |
1284 | |
1285 | slot = path->slots[1]; | |
1286 | if (!path->nodes[1]) { | |
1287 | return 1; | |
1288 | } | |
1289 | upper = path->nodes[1]; | |
e20d96d6 CM |
1290 | upper_node = btrfs_buffer_node(upper); |
1291 | if (slot >= btrfs_header_nritems(&upper_node->header) - 1) { | |
00ec4c51 CM |
1292 | return 1; |
1293 | } | |
e20d96d6 CM |
1294 | right_buf = read_tree_block(root, |
1295 | btrfs_node_blockptr(btrfs_buffer_node(upper), slot + 1)); | |
1296 | right = btrfs_buffer_leaf(right_buf); | |
123abc88 | 1297 | free_space = btrfs_leaf_free_space(root, right); |
0783fcfc | 1298 | if (free_space < data_size + sizeof(struct btrfs_item)) { |
234b63a0 | 1299 | btrfs_block_release(root, right_buf); |
00ec4c51 CM |
1300 | return 1; |
1301 | } | |
02217ed2 | 1302 | /* cow and double check */ |
54aa1f4d CM |
1303 | ret = btrfs_cow_block(trans, root, right_buf, upper, |
1304 | slot + 1, &right_buf); | |
1305 | if (ret) { | |
1306 | btrfs_block_release(root, right_buf); | |
1307 | return 1; | |
1308 | } | |
e20d96d6 | 1309 | right = btrfs_buffer_leaf(right_buf); |
123abc88 | 1310 | free_space = btrfs_leaf_free_space(root, right); |
0783fcfc | 1311 | if (free_space < data_size + sizeof(struct btrfs_item)) { |
234b63a0 | 1312 | btrfs_block_release(root, right_buf); |
02217ed2 CM |
1313 | return 1; |
1314 | } | |
1315 | ||
7518a238 | 1316 | left_nritems = btrfs_header_nritems(&left->header); |
a429e513 CM |
1317 | if (left_nritems == 0) { |
1318 | btrfs_block_release(root, right_buf); | |
1319 | return 1; | |
1320 | } | |
1321 | for (i = left_nritems - 1; i >= 1; i--) { | |
00ec4c51 CM |
1322 | item = left->items + i; |
1323 | if (path->slots[0] == i) | |
1324 | push_space += data_size + sizeof(*item); | |
0783fcfc CM |
1325 | if (btrfs_item_size(item) + sizeof(*item) + push_space > |
1326 | free_space) | |
00ec4c51 CM |
1327 | break; |
1328 | push_items++; | |
0783fcfc | 1329 | push_space += btrfs_item_size(item) + sizeof(*item); |
00ec4c51 CM |
1330 | } |
1331 | if (push_items == 0) { | |
234b63a0 | 1332 | btrfs_block_release(root, right_buf); |
00ec4c51 CM |
1333 | return 1; |
1334 | } | |
a429e513 CM |
1335 | if (push_items == left_nritems) |
1336 | WARN_ON(1); | |
7518a238 | 1337 | right_nritems = btrfs_header_nritems(&right->header); |
00ec4c51 | 1338 | /* push left to right */ |
0783fcfc | 1339 | push_space = btrfs_item_end(left->items + left_nritems - push_items); |
123abc88 | 1340 | push_space -= leaf_data_end(root, left); |
00ec4c51 | 1341 | /* make room in the right data area */ |
d6025579 CM |
1342 | btrfs_memmove(root, right, btrfs_leaf_data(right) + |
1343 | leaf_data_end(root, right) - push_space, | |
1344 | btrfs_leaf_data(right) + | |
1345 | leaf_data_end(root, right), BTRFS_LEAF_DATA_SIZE(root) - | |
1346 | leaf_data_end(root, right)); | |
00ec4c51 | 1347 | /* copy from the left data area */ |
d6025579 CM |
1348 | btrfs_memcpy(root, right, btrfs_leaf_data(right) + |
1349 | BTRFS_LEAF_DATA_SIZE(root) - push_space, | |
1350 | btrfs_leaf_data(left) + leaf_data_end(root, left), | |
1351 | push_space); | |
1352 | btrfs_memmove(root, right, right->items + push_items, right->items, | |
0783fcfc | 1353 | right_nritems * sizeof(struct btrfs_item)); |
00ec4c51 | 1354 | /* copy the items from left to right */ |
d6025579 CM |
1355 | btrfs_memcpy(root, right, right->items, left->items + |
1356 | left_nritems - push_items, | |
1357 | push_items * sizeof(struct btrfs_item)); | |
00ec4c51 CM |
1358 | |
1359 | /* update the item pointers */ | |
7518a238 CM |
1360 | right_nritems += push_items; |
1361 | btrfs_set_header_nritems(&right->header, right_nritems); | |
123abc88 | 1362 | push_space = BTRFS_LEAF_DATA_SIZE(root); |
7518a238 | 1363 | for (i = 0; i < right_nritems; i++) { |
0783fcfc CM |
1364 | btrfs_set_item_offset(right->items + i, push_space - |
1365 | btrfs_item_size(right->items + i)); | |
1366 | push_space = btrfs_item_offset(right->items + i); | |
00ec4c51 | 1367 | } |
7518a238 CM |
1368 | left_nritems -= push_items; |
1369 | btrfs_set_header_nritems(&left->header, left_nritems); | |
00ec4c51 | 1370 | |
d6025579 CM |
1371 | btrfs_mark_buffer_dirty(left_buf); |
1372 | btrfs_mark_buffer_dirty(right_buf); | |
a429e513 | 1373 | |
d6025579 | 1374 | btrfs_memcpy(root, upper_node, &upper_node->ptrs[slot + 1].key, |
e2fa7227 | 1375 | &right->items[0].key, sizeof(struct btrfs_disk_key)); |
d6025579 | 1376 | btrfs_mark_buffer_dirty(upper); |
02217ed2 | 1377 | |
00ec4c51 | 1378 | /* then fixup the leaf pointer in the path */ |
7518a238 CM |
1379 | if (path->slots[0] >= left_nritems) { |
1380 | path->slots[0] -= left_nritems; | |
234b63a0 | 1381 | btrfs_block_release(root, path->nodes[0]); |
00ec4c51 CM |
1382 | path->nodes[0] = right_buf; |
1383 | path->slots[1] += 1; | |
1384 | } else { | |
234b63a0 | 1385 | btrfs_block_release(root, right_buf); |
00ec4c51 | 1386 | } |
098f59c2 CM |
1387 | if (path->nodes[1]) |
1388 | check_node(root, path, 1); | |
00ec4c51 CM |
1389 | return 0; |
1390 | } | |
74123bd7 CM |
1391 | /* |
1392 | * push some data in the path leaf to the left, trying to free up at | |
1393 | * least data_size bytes. returns zero if the push worked, nonzero otherwise | |
1394 | */ | |
e089f05c CM |
1395 | static int push_leaf_left(struct btrfs_trans_handle *trans, struct btrfs_root |
1396 | *root, struct btrfs_path *path, int data_size) | |
be0e5c09 | 1397 | { |
e20d96d6 CM |
1398 | struct buffer_head *right_buf = path->nodes[0]; |
1399 | struct btrfs_leaf *right = btrfs_buffer_leaf(right_buf); | |
1400 | struct buffer_head *t; | |
234b63a0 | 1401 | struct btrfs_leaf *left; |
be0e5c09 CM |
1402 | int slot; |
1403 | int i; | |
1404 | int free_space; | |
1405 | int push_space = 0; | |
1406 | int push_items = 0; | |
0783fcfc | 1407 | struct btrfs_item *item; |
7518a238 | 1408 | u32 old_left_nritems; |
aa5d6bed CM |
1409 | int ret = 0; |
1410 | int wret; | |
be0e5c09 CM |
1411 | |
1412 | slot = path->slots[1]; | |
1413 | if (slot == 0) { | |
1414 | return 1; | |
1415 | } | |
1416 | if (!path->nodes[1]) { | |
1417 | return 1; | |
1418 | } | |
e20d96d6 CM |
1419 | t = read_tree_block(root, |
1420 | btrfs_node_blockptr(btrfs_buffer_node(path->nodes[1]), slot - 1)); | |
1421 | left = btrfs_buffer_leaf(t); | |
123abc88 | 1422 | free_space = btrfs_leaf_free_space(root, left); |
0783fcfc | 1423 | if (free_space < data_size + sizeof(struct btrfs_item)) { |
234b63a0 | 1424 | btrfs_block_release(root, t); |
be0e5c09 CM |
1425 | return 1; |
1426 | } | |
02217ed2 CM |
1427 | |
1428 | /* cow and double check */ | |
54aa1f4d CM |
1429 | ret = btrfs_cow_block(trans, root, t, path->nodes[1], slot - 1, &t); |
1430 | if (ret) { | |
1431 | /* we hit -ENOSPC, but it isn't fatal here */ | |
1432 | return 1; | |
1433 | } | |
e20d96d6 | 1434 | left = btrfs_buffer_leaf(t); |
123abc88 | 1435 | free_space = btrfs_leaf_free_space(root, left); |
0783fcfc | 1436 | if (free_space < data_size + sizeof(struct btrfs_item)) { |
234b63a0 | 1437 | btrfs_block_release(root, t); |
02217ed2 CM |
1438 | return 1; |
1439 | } | |
1440 | ||
a429e513 CM |
1441 | if (btrfs_header_nritems(&right->header) == 0) { |
1442 | btrfs_block_release(root, t); | |
1443 | return 1; | |
1444 | } | |
1445 | ||
1446 | for (i = 0; i < btrfs_header_nritems(&right->header) - 1; i++) { | |
be0e5c09 CM |
1447 | item = right->items + i; |
1448 | if (path->slots[0] == i) | |
1449 | push_space += data_size + sizeof(*item); | |
0783fcfc CM |
1450 | if (btrfs_item_size(item) + sizeof(*item) + push_space > |
1451 | free_space) | |
be0e5c09 CM |
1452 | break; |
1453 | push_items++; | |
0783fcfc | 1454 | push_space += btrfs_item_size(item) + sizeof(*item); |
be0e5c09 CM |
1455 | } |
1456 | if (push_items == 0) { | |
234b63a0 | 1457 | btrfs_block_release(root, t); |
be0e5c09 CM |
1458 | return 1; |
1459 | } | |
a429e513 CM |
1460 | if (push_items == btrfs_header_nritems(&right->header)) |
1461 | WARN_ON(1); | |
be0e5c09 | 1462 | /* push data from right to left */ |
d6025579 CM |
1463 | btrfs_memcpy(root, left, left->items + |
1464 | btrfs_header_nritems(&left->header), | |
1465 | right->items, push_items * sizeof(struct btrfs_item)); | |
123abc88 | 1466 | push_space = BTRFS_LEAF_DATA_SIZE(root) - |
0783fcfc | 1467 | btrfs_item_offset(right->items + push_items -1); |
d6025579 CM |
1468 | btrfs_memcpy(root, left, btrfs_leaf_data(left) + |
1469 | leaf_data_end(root, left) - push_space, | |
1470 | btrfs_leaf_data(right) + | |
1471 | btrfs_item_offset(right->items + push_items - 1), | |
1472 | push_space); | |
7518a238 | 1473 | old_left_nritems = btrfs_header_nritems(&left->header); |
eb60ceac CM |
1474 | BUG_ON(old_left_nritems < 0); |
1475 | ||
0783fcfc | 1476 | for (i = old_left_nritems; i < old_left_nritems + push_items; i++) { |
123abc88 CM |
1477 | u32 ioff = btrfs_item_offset(left->items + i); |
1478 | btrfs_set_item_offset(left->items + i, ioff - | |
1479 | (BTRFS_LEAF_DATA_SIZE(root) - | |
0783fcfc CM |
1480 | btrfs_item_offset(left->items + |
1481 | old_left_nritems - 1))); | |
be0e5c09 | 1482 | } |
7518a238 | 1483 | btrfs_set_header_nritems(&left->header, old_left_nritems + push_items); |
be0e5c09 CM |
1484 | |
1485 | /* fixup right node */ | |
0783fcfc | 1486 | push_space = btrfs_item_offset(right->items + push_items - 1) - |
123abc88 | 1487 | leaf_data_end(root, right); |
d6025579 CM |
1488 | btrfs_memmove(root, right, btrfs_leaf_data(right) + |
1489 | BTRFS_LEAF_DATA_SIZE(root) - push_space, | |
1490 | btrfs_leaf_data(right) + | |
1491 | leaf_data_end(root, right), push_space); | |
1492 | btrfs_memmove(root, right, right->items, right->items + push_items, | |
7518a238 | 1493 | (btrfs_header_nritems(&right->header) - push_items) * |
0783fcfc | 1494 | sizeof(struct btrfs_item)); |
7518a238 CM |
1495 | btrfs_set_header_nritems(&right->header, |
1496 | btrfs_header_nritems(&right->header) - | |
1497 | push_items); | |
123abc88 | 1498 | push_space = BTRFS_LEAF_DATA_SIZE(root); |
eb60ceac | 1499 | |
7518a238 | 1500 | for (i = 0; i < btrfs_header_nritems(&right->header); i++) { |
0783fcfc CM |
1501 | btrfs_set_item_offset(right->items + i, push_space - |
1502 | btrfs_item_size(right->items + i)); | |
1503 | push_space = btrfs_item_offset(right->items + i); | |
be0e5c09 | 1504 | } |
eb60ceac | 1505 | |
d6025579 CM |
1506 | btrfs_mark_buffer_dirty(t); |
1507 | btrfs_mark_buffer_dirty(right_buf); | |
098f59c2 | 1508 | |
e089f05c | 1509 | wret = fixup_low_keys(trans, root, path, &right->items[0].key, 1); |
aa5d6bed CM |
1510 | if (wret) |
1511 | ret = wret; | |
be0e5c09 CM |
1512 | |
1513 | /* then fixup the leaf pointer in the path */ | |
1514 | if (path->slots[0] < push_items) { | |
1515 | path->slots[0] += old_left_nritems; | |
234b63a0 | 1516 | btrfs_block_release(root, path->nodes[0]); |
eb60ceac | 1517 | path->nodes[0] = t; |
be0e5c09 CM |
1518 | path->slots[1] -= 1; |
1519 | } else { | |
234b63a0 | 1520 | btrfs_block_release(root, t); |
be0e5c09 CM |
1521 | path->slots[0] -= push_items; |
1522 | } | |
eb60ceac | 1523 | BUG_ON(path->slots[0] < 0); |
098f59c2 CM |
1524 | if (path->nodes[1]) |
1525 | check_node(root, path, 1); | |
aa5d6bed | 1526 | return ret; |
be0e5c09 CM |
1527 | } |
1528 | ||
74123bd7 CM |
1529 | /* |
1530 | * split the path's leaf in two, making sure there is at least data_size | |
1531 | * available for the resulting leaf level of the path. | |
aa5d6bed CM |
1532 | * |
1533 | * returns 0 if all went well and < 0 on failure. | |
74123bd7 | 1534 | */ |
e089f05c | 1535 | static int split_leaf(struct btrfs_trans_handle *trans, struct btrfs_root |
d4dbff95 CM |
1536 | *root, struct btrfs_key *ins_key, |
1537 | struct btrfs_path *path, int data_size) | |
be0e5c09 | 1538 | { |
e20d96d6 | 1539 | struct buffer_head *l_buf; |
234b63a0 | 1540 | struct btrfs_leaf *l; |
7518a238 | 1541 | u32 nritems; |
eb60ceac CM |
1542 | int mid; |
1543 | int slot; | |
234b63a0 | 1544 | struct btrfs_leaf *right; |
e20d96d6 | 1545 | struct buffer_head *right_buffer; |
0783fcfc | 1546 | int space_needed = data_size + sizeof(struct btrfs_item); |
be0e5c09 CM |
1547 | int data_copy_size; |
1548 | int rt_data_off; | |
1549 | int i; | |
d4dbff95 | 1550 | int ret = 0; |
aa5d6bed | 1551 | int wret; |
d4dbff95 CM |
1552 | int double_split = 0; |
1553 | struct btrfs_disk_key disk_key; | |
aa5d6bed | 1554 | |
40689478 | 1555 | /* first try to make some room by pushing left and right */ |
e089f05c | 1556 | wret = push_leaf_left(trans, root, path, data_size); |
eaee50e8 CM |
1557 | if (wret < 0) |
1558 | return wret; | |
1559 | if (wret) { | |
e089f05c | 1560 | wret = push_leaf_right(trans, root, path, data_size); |
eaee50e8 CM |
1561 | if (wret < 0) |
1562 | return wret; | |
1563 | } | |
aa5d6bed | 1564 | l_buf = path->nodes[0]; |
e20d96d6 | 1565 | l = btrfs_buffer_leaf(l_buf); |
aa5d6bed CM |
1566 | |
1567 | /* did the pushes work? */ | |
123abc88 CM |
1568 | if (btrfs_leaf_free_space(root, l) >= |
1569 | sizeof(struct btrfs_item) + data_size) | |
aa5d6bed CM |
1570 | return 0; |
1571 | ||
5c680ed6 | 1572 | if (!path->nodes[1]) { |
e089f05c | 1573 | ret = insert_new_root(trans, root, path, 1); |
5c680ed6 CM |
1574 | if (ret) |
1575 | return ret; | |
1576 | } | |
eb60ceac | 1577 | slot = path->slots[0]; |
7518a238 | 1578 | nritems = btrfs_header_nritems(&l->header); |
eb60ceac | 1579 | mid = (nritems + 1)/ 2; |
54aa1f4d | 1580 | |
6702ed49 | 1581 | right_buffer = btrfs_alloc_free_block(trans, root, l_buf->b_blocknr, 0); |
54aa1f4d CM |
1582 | if (IS_ERR(right_buffer)) |
1583 | return PTR_ERR(right_buffer); | |
1584 | ||
e20d96d6 | 1585 | right = btrfs_buffer_leaf(right_buffer); |
123abc88 | 1586 | memset(&right->header, 0, sizeof(right->header)); |
7eccb903 | 1587 | btrfs_set_header_blocknr(&right->header, bh_blocknr(right_buffer)); |
7f5c1516 | 1588 | btrfs_set_header_generation(&right->header, trans->transid); |
4d775673 | 1589 | btrfs_set_header_owner(&right->header, root->root_key.objectid); |
7518a238 | 1590 | btrfs_set_header_level(&right->header, 0); |
3eb0314d CM |
1591 | memcpy(right->header.fsid, root->fs_info->disk_super->fsid, |
1592 | sizeof(right->header.fsid)); | |
d4dbff95 CM |
1593 | if (mid <= slot) { |
1594 | if (nritems == 1 || | |
1595 | leaf_space_used(l, mid, nritems - mid) + space_needed > | |
1596 | BTRFS_LEAF_DATA_SIZE(root)) { | |
1597 | if (slot >= nritems) { | |
1598 | btrfs_cpu_key_to_disk(&disk_key, ins_key); | |
1599 | btrfs_set_header_nritems(&right->header, 0); | |
1600 | wret = insert_ptr(trans, root, path, | |
1601 | &disk_key, | |
7eccb903 | 1602 | bh_blocknr(right_buffer), |
d4dbff95 CM |
1603 | path->slots[1] + 1, 1); |
1604 | if (wret) | |
1605 | ret = wret; | |
1606 | btrfs_block_release(root, path->nodes[0]); | |
1607 | path->nodes[0] = right_buffer; | |
1608 | path->slots[0] = 0; | |
1609 | path->slots[1] += 1; | |
1610 | return ret; | |
1611 | } | |
1612 | mid = slot; | |
1613 | double_split = 1; | |
1614 | } | |
1615 | } else { | |
1616 | if (leaf_space_used(l, 0, mid + 1) + space_needed > | |
1617 | BTRFS_LEAF_DATA_SIZE(root)) { | |
1618 | if (slot == 0) { | |
1619 | btrfs_cpu_key_to_disk(&disk_key, ins_key); | |
1620 | btrfs_set_header_nritems(&right->header, 0); | |
1621 | wret = insert_ptr(trans, root, path, | |
1622 | &disk_key, | |
7eccb903 | 1623 | bh_blocknr(right_buffer), |
098f59c2 | 1624 | path->slots[1], 1); |
d4dbff95 CM |
1625 | if (wret) |
1626 | ret = wret; | |
1627 | btrfs_block_release(root, path->nodes[0]); | |
1628 | path->nodes[0] = right_buffer; | |
1629 | path->slots[0] = 0; | |
a429e513 CM |
1630 | if (path->slots[1] == 0) { |
1631 | wret = fixup_low_keys(trans, root, | |
1632 | path, &disk_key, 1); | |
1633 | if (wret) | |
1634 | ret = wret; | |
1635 | } | |
d4dbff95 CM |
1636 | return ret; |
1637 | } | |
1638 | mid = slot; | |
1639 | double_split = 1; | |
1640 | } | |
1641 | } | |
1642 | btrfs_set_header_nritems(&right->header, nritems - mid); | |
123abc88 CM |
1643 | data_copy_size = btrfs_item_end(l->items + mid) - |
1644 | leaf_data_end(root, l); | |
d6025579 CM |
1645 | btrfs_memcpy(root, right, right->items, l->items + mid, |
1646 | (nritems - mid) * sizeof(struct btrfs_item)); | |
1647 | btrfs_memcpy(root, right, | |
1648 | btrfs_leaf_data(right) + BTRFS_LEAF_DATA_SIZE(root) - | |
1649 | data_copy_size, btrfs_leaf_data(l) + | |
1650 | leaf_data_end(root, l), data_copy_size); | |
123abc88 CM |
1651 | rt_data_off = BTRFS_LEAF_DATA_SIZE(root) - |
1652 | btrfs_item_end(l->items + mid); | |
74123bd7 | 1653 | |
0783fcfc | 1654 | for (i = 0; i < btrfs_header_nritems(&right->header); i++) { |
123abc88 | 1655 | u32 ioff = btrfs_item_offset(right->items + i); |
0783fcfc CM |
1656 | btrfs_set_item_offset(right->items + i, ioff + rt_data_off); |
1657 | } | |
74123bd7 | 1658 | |
7518a238 | 1659 | btrfs_set_header_nritems(&l->header, mid); |
aa5d6bed | 1660 | ret = 0; |
e089f05c | 1661 | wret = insert_ptr(trans, root, path, &right->items[0].key, |
7eccb903 | 1662 | bh_blocknr(right_buffer), path->slots[1] + 1, 1); |
aa5d6bed CM |
1663 | if (wret) |
1664 | ret = wret; | |
d6025579 CM |
1665 | btrfs_mark_buffer_dirty(right_buffer); |
1666 | btrfs_mark_buffer_dirty(l_buf); | |
eb60ceac | 1667 | BUG_ON(path->slots[0] != slot); |
be0e5c09 | 1668 | if (mid <= slot) { |
234b63a0 | 1669 | btrfs_block_release(root, path->nodes[0]); |
eb60ceac | 1670 | path->nodes[0] = right_buffer; |
be0e5c09 CM |
1671 | path->slots[0] -= mid; |
1672 | path->slots[1] += 1; | |
eb60ceac | 1673 | } else |
234b63a0 | 1674 | btrfs_block_release(root, right_buffer); |
eb60ceac | 1675 | BUG_ON(path->slots[0] < 0); |
098f59c2 | 1676 | check_node(root, path, 1); |
d4dbff95 CM |
1677 | |
1678 | if (!double_split) | |
1679 | return ret; | |
6702ed49 | 1680 | right_buffer = btrfs_alloc_free_block(trans, root, l_buf->b_blocknr, 0); |
54aa1f4d CM |
1681 | if (IS_ERR(right_buffer)) |
1682 | return PTR_ERR(right_buffer); | |
1683 | ||
d4dbff95 CM |
1684 | right = btrfs_buffer_leaf(right_buffer); |
1685 | memset(&right->header, 0, sizeof(right->header)); | |
7eccb903 | 1686 | btrfs_set_header_blocknr(&right->header, bh_blocknr(right_buffer)); |
d4dbff95 | 1687 | btrfs_set_header_generation(&right->header, trans->transid); |
4d775673 | 1688 | btrfs_set_header_owner(&right->header, root->root_key.objectid); |
d4dbff95 | 1689 | btrfs_set_header_level(&right->header, 0); |
3eb0314d CM |
1690 | memcpy(right->header.fsid, root->fs_info->disk_super->fsid, |
1691 | sizeof(right->header.fsid)); | |
d4dbff95 CM |
1692 | btrfs_cpu_key_to_disk(&disk_key, ins_key); |
1693 | btrfs_set_header_nritems(&right->header, 0); | |
1694 | wret = insert_ptr(trans, root, path, | |
1695 | &disk_key, | |
7eccb903 | 1696 | bh_blocknr(right_buffer), |
d4dbff95 CM |
1697 | path->slots[1], 1); |
1698 | if (wret) | |
1699 | ret = wret; | |
a429e513 CM |
1700 | if (path->slots[1] == 0) { |
1701 | wret = fixup_low_keys(trans, root, path, &disk_key, 1); | |
1702 | if (wret) | |
1703 | ret = wret; | |
1704 | } | |
d4dbff95 CM |
1705 | btrfs_block_release(root, path->nodes[0]); |
1706 | path->nodes[0] = right_buffer; | |
1707 | path->slots[0] = 0; | |
1708 | check_node(root, path, 1); | |
1709 | check_leaf(root, path, 0); | |
be0e5c09 CM |
1710 | return ret; |
1711 | } | |
1712 | ||
b18c6685 CM |
1713 | int btrfs_truncate_item(struct btrfs_trans_handle *trans, |
1714 | struct btrfs_root *root, | |
1715 | struct btrfs_path *path, | |
1716 | u32 new_size) | |
1717 | { | |
1718 | int ret = 0; | |
1719 | int slot; | |
1720 | int slot_orig; | |
1721 | struct btrfs_leaf *leaf; | |
1722 | struct buffer_head *leaf_buf; | |
1723 | u32 nritems; | |
1724 | unsigned int data_end; | |
1725 | unsigned int old_data_start; | |
1726 | unsigned int old_size; | |
1727 | unsigned int size_diff; | |
1728 | int i; | |
1729 | ||
1730 | slot_orig = path->slots[0]; | |
1731 | leaf_buf = path->nodes[0]; | |
1732 | leaf = btrfs_buffer_leaf(leaf_buf); | |
1733 | ||
1734 | nritems = btrfs_header_nritems(&leaf->header); | |
1735 | data_end = leaf_data_end(root, leaf); | |
1736 | ||
1737 | slot = path->slots[0]; | |
1738 | old_data_start = btrfs_item_offset(leaf->items + slot); | |
1739 | old_size = btrfs_item_size(leaf->items + slot); | |
1740 | BUG_ON(old_size <= new_size); | |
1741 | size_diff = old_size - new_size; | |
1742 | ||
1743 | BUG_ON(slot < 0); | |
1744 | BUG_ON(slot >= nritems); | |
1745 | ||
1746 | /* | |
1747 | * item0..itemN ... dataN.offset..dataN.size .. data0.size | |
1748 | */ | |
1749 | /* first correct the data pointers */ | |
1750 | for (i = slot; i < nritems; i++) { | |
1751 | u32 ioff = btrfs_item_offset(leaf->items + i); | |
1752 | btrfs_set_item_offset(leaf->items + i, | |
1753 | ioff + size_diff); | |
1754 | } | |
1755 | /* shift the data */ | |
b18c6685 CM |
1756 | btrfs_memmove(root, leaf, btrfs_leaf_data(leaf) + |
1757 | data_end + size_diff, btrfs_leaf_data(leaf) + | |
1758 | data_end, old_data_start + new_size - data_end); | |
1759 | btrfs_set_item_size(leaf->items + slot, new_size); | |
1760 | btrfs_mark_buffer_dirty(leaf_buf); | |
1761 | ||
1762 | ret = 0; | |
1763 | if (btrfs_leaf_free_space(root, leaf) < 0) | |
1764 | BUG(); | |
1765 | check_leaf(root, path, 0); | |
1766 | return ret; | |
1767 | } | |
1768 | ||
6567e837 CM |
1769 | int btrfs_extend_item(struct btrfs_trans_handle *trans, struct btrfs_root |
1770 | *root, struct btrfs_path *path, u32 data_size) | |
1771 | { | |
1772 | int ret = 0; | |
1773 | int slot; | |
1774 | int slot_orig; | |
1775 | struct btrfs_leaf *leaf; | |
1776 | struct buffer_head *leaf_buf; | |
1777 | u32 nritems; | |
1778 | unsigned int data_end; | |
1779 | unsigned int old_data; | |
1780 | unsigned int old_size; | |
1781 | int i; | |
1782 | ||
1783 | slot_orig = path->slots[0]; | |
1784 | leaf_buf = path->nodes[0]; | |
1785 | leaf = btrfs_buffer_leaf(leaf_buf); | |
1786 | ||
1787 | nritems = btrfs_header_nritems(&leaf->header); | |
1788 | data_end = leaf_data_end(root, leaf); | |
1789 | ||
1790 | if (btrfs_leaf_free_space(root, leaf) < data_size) | |
1791 | BUG(); | |
1792 | slot = path->slots[0]; | |
1793 | old_data = btrfs_item_end(leaf->items + slot); | |
1794 | ||
1795 | BUG_ON(slot < 0); | |
1796 | BUG_ON(slot >= nritems); | |
1797 | ||
1798 | /* | |
1799 | * item0..itemN ... dataN.offset..dataN.size .. data0.size | |
1800 | */ | |
1801 | /* first correct the data pointers */ | |
1802 | for (i = slot; i < nritems; i++) { | |
1803 | u32 ioff = btrfs_item_offset(leaf->items + i); | |
1804 | btrfs_set_item_offset(leaf->items + i, | |
1805 | ioff - data_size); | |
1806 | } | |
1807 | /* shift the data */ | |
1808 | btrfs_memmove(root, leaf, btrfs_leaf_data(leaf) + | |
1809 | data_end - data_size, btrfs_leaf_data(leaf) + | |
1810 | data_end, old_data - data_end); | |
1811 | data_end = old_data; | |
1812 | old_size = btrfs_item_size(leaf->items + slot); | |
1813 | btrfs_set_item_size(leaf->items + slot, old_size + data_size); | |
1814 | btrfs_mark_buffer_dirty(leaf_buf); | |
1815 | ||
1816 | ret = 0; | |
1817 | if (btrfs_leaf_free_space(root, leaf) < 0) | |
1818 | BUG(); | |
1819 | check_leaf(root, path, 0); | |
1820 | return ret; | |
1821 | } | |
1822 | ||
74123bd7 CM |
1823 | /* |
1824 | * Given a key and some data, insert an item into the tree. | |
1825 | * This does all the path init required, making room in the tree if needed. | |
1826 | */ | |
e089f05c CM |
1827 | int btrfs_insert_empty_item(struct btrfs_trans_handle *trans, struct btrfs_root |
1828 | *root, struct btrfs_path *path, struct btrfs_key | |
1829 | *cpu_key, u32 data_size) | |
be0e5c09 | 1830 | { |
aa5d6bed | 1831 | int ret = 0; |
be0e5c09 | 1832 | int slot; |
eb60ceac | 1833 | int slot_orig; |
234b63a0 | 1834 | struct btrfs_leaf *leaf; |
e20d96d6 | 1835 | struct buffer_head *leaf_buf; |
7518a238 | 1836 | u32 nritems; |
be0e5c09 | 1837 | unsigned int data_end; |
e2fa7227 CM |
1838 | struct btrfs_disk_key disk_key; |
1839 | ||
1840 | btrfs_cpu_key_to_disk(&disk_key, cpu_key); | |
be0e5c09 | 1841 | |
74123bd7 | 1842 | /* create a root if there isn't one */ |
5c680ed6 | 1843 | if (!root->node) |
cfaa7295 | 1844 | BUG(); |
e089f05c | 1845 | ret = btrfs_search_slot(trans, root, cpu_key, path, data_size, 1); |
eb60ceac | 1846 | if (ret == 0) { |
f0930a37 | 1847 | return -EEXIST; |
aa5d6bed | 1848 | } |
ed2ff2cb CM |
1849 | if (ret < 0) |
1850 | goto out; | |
be0e5c09 | 1851 | |
62e2749e CM |
1852 | slot_orig = path->slots[0]; |
1853 | leaf_buf = path->nodes[0]; | |
e20d96d6 | 1854 | leaf = btrfs_buffer_leaf(leaf_buf); |
74123bd7 | 1855 | |
7518a238 | 1856 | nritems = btrfs_header_nritems(&leaf->header); |
123abc88 | 1857 | data_end = leaf_data_end(root, leaf); |
eb60ceac | 1858 | |
123abc88 | 1859 | if (btrfs_leaf_free_space(root, leaf) < |
d4dbff95 | 1860 | sizeof(struct btrfs_item) + data_size) { |
be0e5c09 | 1861 | BUG(); |
d4dbff95 | 1862 | } |
62e2749e | 1863 | slot = path->slots[0]; |
eb60ceac | 1864 | BUG_ON(slot < 0); |
be0e5c09 CM |
1865 | if (slot != nritems) { |
1866 | int i; | |
0783fcfc | 1867 | unsigned int old_data = btrfs_item_end(leaf->items + slot); |
be0e5c09 CM |
1868 | |
1869 | /* | |
1870 | * item0..itemN ... dataN.offset..dataN.size .. data0.size | |
1871 | */ | |
1872 | /* first correct the data pointers */ | |
0783fcfc | 1873 | for (i = slot; i < nritems; i++) { |
123abc88 | 1874 | u32 ioff = btrfs_item_offset(leaf->items + i); |
0783fcfc CM |
1875 | btrfs_set_item_offset(leaf->items + i, |
1876 | ioff - data_size); | |
1877 | } | |
be0e5c09 CM |
1878 | |
1879 | /* shift the items */ | |
d6025579 CM |
1880 | btrfs_memmove(root, leaf, leaf->items + slot + 1, |
1881 | leaf->items + slot, | |
1882 | (nritems - slot) * sizeof(struct btrfs_item)); | |
be0e5c09 CM |
1883 | |
1884 | /* shift the data */ | |
d6025579 CM |
1885 | btrfs_memmove(root, leaf, btrfs_leaf_data(leaf) + |
1886 | data_end - data_size, btrfs_leaf_data(leaf) + | |
1887 | data_end, old_data - data_end); | |
be0e5c09 CM |
1888 | data_end = old_data; |
1889 | } | |
62e2749e | 1890 | /* setup the item for the new data */ |
d6025579 CM |
1891 | btrfs_memcpy(root, leaf, &leaf->items[slot].key, &disk_key, |
1892 | sizeof(struct btrfs_disk_key)); | |
0783fcfc CM |
1893 | btrfs_set_item_offset(leaf->items + slot, data_end - data_size); |
1894 | btrfs_set_item_size(leaf->items + slot, data_size); | |
7518a238 | 1895 | btrfs_set_header_nritems(&leaf->header, nritems + 1); |
d6025579 | 1896 | btrfs_mark_buffer_dirty(leaf_buf); |
aa5d6bed CM |
1897 | |
1898 | ret = 0; | |
8e19f2cd | 1899 | if (slot == 0) |
e089f05c | 1900 | ret = fixup_low_keys(trans, root, path, &disk_key, 1); |
aa5d6bed | 1901 | |
123abc88 | 1902 | if (btrfs_leaf_free_space(root, leaf) < 0) |
be0e5c09 | 1903 | BUG(); |
62e2749e | 1904 | check_leaf(root, path, 0); |
ed2ff2cb | 1905 | out: |
62e2749e CM |
1906 | return ret; |
1907 | } | |
1908 | ||
1909 | /* | |
1910 | * Given a key and some data, insert an item into the tree. | |
1911 | * This does all the path init required, making room in the tree if needed. | |
1912 | */ | |
e089f05c CM |
1913 | int btrfs_insert_item(struct btrfs_trans_handle *trans, struct btrfs_root |
1914 | *root, struct btrfs_key *cpu_key, void *data, u32 | |
1915 | data_size) | |
62e2749e CM |
1916 | { |
1917 | int ret = 0; | |
2c90e5d6 | 1918 | struct btrfs_path *path; |
62e2749e CM |
1919 | u8 *ptr; |
1920 | ||
2c90e5d6 CM |
1921 | path = btrfs_alloc_path(); |
1922 | BUG_ON(!path); | |
2c90e5d6 | 1923 | ret = btrfs_insert_empty_item(trans, root, path, cpu_key, data_size); |
62e2749e | 1924 | if (!ret) { |
2c90e5d6 CM |
1925 | ptr = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]), |
1926 | path->slots[0], u8); | |
1927 | btrfs_memcpy(root, path->nodes[0]->b_data, | |
d6025579 | 1928 | ptr, data, data_size); |
2c90e5d6 | 1929 | btrfs_mark_buffer_dirty(path->nodes[0]); |
62e2749e | 1930 | } |
2c90e5d6 | 1931 | btrfs_free_path(path); |
aa5d6bed | 1932 | return ret; |
be0e5c09 CM |
1933 | } |
1934 | ||
74123bd7 | 1935 | /* |
5de08d7d | 1936 | * delete the pointer from a given node. |
74123bd7 CM |
1937 | * |
1938 | * If the delete empties a node, the node is removed from the tree, | |
1939 | * continuing all the way the root if required. The root is converted into | |
1940 | * a leaf if all the nodes are emptied. | |
1941 | */ | |
e089f05c CM |
1942 | static int del_ptr(struct btrfs_trans_handle *trans, struct btrfs_root *root, |
1943 | struct btrfs_path *path, int level, int slot) | |
be0e5c09 | 1944 | { |
234b63a0 | 1945 | struct btrfs_node *node; |
e20d96d6 | 1946 | struct buffer_head *parent = path->nodes[level]; |
7518a238 | 1947 | u32 nritems; |
aa5d6bed | 1948 | int ret = 0; |
bb803951 | 1949 | int wret; |
be0e5c09 | 1950 | |
e20d96d6 | 1951 | node = btrfs_buffer_node(parent); |
7518a238 | 1952 | nritems = btrfs_header_nritems(&node->header); |
bb803951 | 1953 | if (slot != nritems -1) { |
d6025579 CM |
1954 | btrfs_memmove(root, node, node->ptrs + slot, |
1955 | node->ptrs + slot + 1, | |
1956 | sizeof(struct btrfs_key_ptr) * | |
1957 | (nritems - slot - 1)); | |
bb803951 | 1958 | } |
7518a238 CM |
1959 | nritems--; |
1960 | btrfs_set_header_nritems(&node->header, nritems); | |
1961 | if (nritems == 0 && parent == root->node) { | |
e20d96d6 CM |
1962 | struct btrfs_header *header = btrfs_buffer_header(root->node); |
1963 | BUG_ON(btrfs_header_level(header) != 1); | |
bb803951 | 1964 | /* just turn the root into a leaf and break */ |
e20d96d6 | 1965 | btrfs_set_header_level(header, 0); |
bb803951 | 1966 | } else if (slot == 0) { |
e089f05c | 1967 | wret = fixup_low_keys(trans, root, path, &node->ptrs[0].key, |
123abc88 | 1968 | level + 1); |
0f70abe2 CM |
1969 | if (wret) |
1970 | ret = wret; | |
be0e5c09 | 1971 | } |
d6025579 | 1972 | btrfs_mark_buffer_dirty(parent); |
aa5d6bed | 1973 | return ret; |
be0e5c09 CM |
1974 | } |
1975 | ||
74123bd7 CM |
1976 | /* |
1977 | * delete the item at the leaf level in path. If that empties | |
1978 | * the leaf, remove it from the tree | |
1979 | */ | |
e089f05c CM |
1980 | int btrfs_del_item(struct btrfs_trans_handle *trans, struct btrfs_root *root, |
1981 | struct btrfs_path *path) | |
be0e5c09 | 1982 | { |
be0e5c09 | 1983 | int slot; |
234b63a0 | 1984 | struct btrfs_leaf *leaf; |
e20d96d6 | 1985 | struct buffer_head *leaf_buf; |
be0e5c09 CM |
1986 | int doff; |
1987 | int dsize; | |
aa5d6bed CM |
1988 | int ret = 0; |
1989 | int wret; | |
7518a238 | 1990 | u32 nritems; |
be0e5c09 | 1991 | |
eb60ceac | 1992 | leaf_buf = path->nodes[0]; |
e20d96d6 | 1993 | leaf = btrfs_buffer_leaf(leaf_buf); |
4920c9ac | 1994 | slot = path->slots[0]; |
0783fcfc CM |
1995 | doff = btrfs_item_offset(leaf->items + slot); |
1996 | dsize = btrfs_item_size(leaf->items + slot); | |
7518a238 | 1997 | nritems = btrfs_header_nritems(&leaf->header); |
be0e5c09 | 1998 | |
7518a238 | 1999 | if (slot != nritems - 1) { |
be0e5c09 | 2000 | int i; |
123abc88 | 2001 | int data_end = leaf_data_end(root, leaf); |
d6025579 CM |
2002 | btrfs_memmove(root, leaf, btrfs_leaf_data(leaf) + |
2003 | data_end + dsize, | |
2004 | btrfs_leaf_data(leaf) + data_end, | |
2005 | doff - data_end); | |
0783fcfc | 2006 | for (i = slot + 1; i < nritems; i++) { |
123abc88 | 2007 | u32 ioff = btrfs_item_offset(leaf->items + i); |
0783fcfc CM |
2008 | btrfs_set_item_offset(leaf->items + i, ioff + dsize); |
2009 | } | |
d6025579 CM |
2010 | btrfs_memmove(root, leaf, leaf->items + slot, |
2011 | leaf->items + slot + 1, | |
2012 | sizeof(struct btrfs_item) * | |
2013 | (nritems - slot - 1)); | |
be0e5c09 | 2014 | } |
7518a238 CM |
2015 | btrfs_set_header_nritems(&leaf->header, nritems - 1); |
2016 | nritems--; | |
74123bd7 | 2017 | /* delete the leaf if we've emptied it */ |
7518a238 | 2018 | if (nritems == 0) { |
eb60ceac | 2019 | if (leaf_buf == root->node) { |
7518a238 | 2020 | btrfs_set_header_level(&leaf->header, 0); |
9a8dd150 | 2021 | } else { |
e089f05c | 2022 | clean_tree_block(trans, root, leaf_buf); |
d6025579 | 2023 | wait_on_buffer(leaf_buf); |
e089f05c | 2024 | wret = del_ptr(trans, root, path, 1, path->slots[1]); |
aa5d6bed CM |
2025 | if (wret) |
2026 | ret = wret; | |
e089f05c | 2027 | wret = btrfs_free_extent(trans, root, |
7eccb903 | 2028 | bh_blocknr(leaf_buf), 1, 1); |
0f70abe2 CM |
2029 | if (wret) |
2030 | ret = wret; | |
9a8dd150 | 2031 | } |
be0e5c09 | 2032 | } else { |
7518a238 | 2033 | int used = leaf_space_used(leaf, 0, nritems); |
aa5d6bed | 2034 | if (slot == 0) { |
e089f05c CM |
2035 | wret = fixup_low_keys(trans, root, path, |
2036 | &leaf->items[0].key, 1); | |
aa5d6bed CM |
2037 | if (wret) |
2038 | ret = wret; | |
2039 | } | |
aa5d6bed | 2040 | |
74123bd7 | 2041 | /* delete the leaf if it is mostly empty */ |
123abc88 | 2042 | if (used < BTRFS_LEAF_DATA_SIZE(root) / 3) { |
be0e5c09 CM |
2043 | /* push_leaf_left fixes the path. |
2044 | * make sure the path still points to our leaf | |
2045 | * for possible call to del_ptr below | |
2046 | */ | |
4920c9ac | 2047 | slot = path->slots[1]; |
e20d96d6 | 2048 | get_bh(leaf_buf); |
e089f05c | 2049 | wret = push_leaf_left(trans, root, path, 1); |
54aa1f4d | 2050 | if (wret < 0 && wret != -ENOSPC) |
aa5d6bed | 2051 | ret = wret; |
f0930a37 | 2052 | if (path->nodes[0] == leaf_buf && |
7518a238 | 2053 | btrfs_header_nritems(&leaf->header)) { |
e089f05c | 2054 | wret = push_leaf_right(trans, root, path, 1); |
54aa1f4d | 2055 | if (wret < 0 && wret != -ENOSPC) |
aa5d6bed CM |
2056 | ret = wret; |
2057 | } | |
7518a238 | 2058 | if (btrfs_header_nritems(&leaf->header) == 0) { |
7eccb903 | 2059 | u64 blocknr = bh_blocknr(leaf_buf); |
e089f05c | 2060 | clean_tree_block(trans, root, leaf_buf); |
d6025579 | 2061 | wait_on_buffer(leaf_buf); |
e089f05c | 2062 | wret = del_ptr(trans, root, path, 1, slot); |
aa5d6bed CM |
2063 | if (wret) |
2064 | ret = wret; | |
234b63a0 | 2065 | btrfs_block_release(root, leaf_buf); |
e089f05c CM |
2066 | wret = btrfs_free_extent(trans, root, blocknr, |
2067 | 1, 1); | |
0f70abe2 CM |
2068 | if (wret) |
2069 | ret = wret; | |
5de08d7d | 2070 | } else { |
d6025579 | 2071 | btrfs_mark_buffer_dirty(leaf_buf); |
234b63a0 | 2072 | btrfs_block_release(root, leaf_buf); |
be0e5c09 | 2073 | } |
d5719762 | 2074 | } else { |
d6025579 | 2075 | btrfs_mark_buffer_dirty(leaf_buf); |
be0e5c09 CM |
2076 | } |
2077 | } | |
aa5d6bed | 2078 | return ret; |
be0e5c09 CM |
2079 | } |
2080 | ||
97571fd0 CM |
2081 | /* |
2082 | * walk up the tree as far as required to find the next leaf. | |
0f70abe2 CM |
2083 | * returns 0 if it found something or 1 if there are no greater leaves. |
2084 | * returns < 0 on io errors. | |
97571fd0 | 2085 | */ |
234b63a0 | 2086 | int btrfs_next_leaf(struct btrfs_root *root, struct btrfs_path *path) |
d97e63b6 CM |
2087 | { |
2088 | int slot; | |
2089 | int level = 1; | |
2090 | u64 blocknr; | |
e20d96d6 CM |
2091 | struct buffer_head *c; |
2092 | struct btrfs_node *c_node; | |
2093 | struct buffer_head *next = NULL; | |
d97e63b6 | 2094 | |
234b63a0 | 2095 | while(level < BTRFS_MAX_LEVEL) { |
d97e63b6 | 2096 | if (!path->nodes[level]) |
0f70abe2 | 2097 | return 1; |
d97e63b6 CM |
2098 | slot = path->slots[level] + 1; |
2099 | c = path->nodes[level]; | |
e20d96d6 CM |
2100 | c_node = btrfs_buffer_node(c); |
2101 | if (slot >= btrfs_header_nritems(&c_node->header)) { | |
d97e63b6 CM |
2102 | level++; |
2103 | continue; | |
2104 | } | |
e20d96d6 | 2105 | blocknr = btrfs_node_blockptr(c_node, slot); |
cfaa7295 | 2106 | if (next) |
234b63a0 | 2107 | btrfs_block_release(root, next); |
6702ed49 CM |
2108 | if (path->reada) |
2109 | reada_for_search(root, path, level, slot); | |
d97e63b6 CM |
2110 | next = read_tree_block(root, blocknr); |
2111 | break; | |
2112 | } | |
2113 | path->slots[level] = slot; | |
2114 | while(1) { | |
2115 | level--; | |
2116 | c = path->nodes[level]; | |
234b63a0 | 2117 | btrfs_block_release(root, c); |
d97e63b6 CM |
2118 | path->nodes[level] = next; |
2119 | path->slots[level] = 0; | |
2120 | if (!level) | |
2121 | break; | |
6702ed49 CM |
2122 | if (path->reada) |
2123 | reada_for_search(root, path, level, slot); | |
1d4f8a0c | 2124 | next = read_tree_block(root, |
e20d96d6 | 2125 | btrfs_node_blockptr(btrfs_buffer_node(next), 0)); |
d97e63b6 CM |
2126 | } |
2127 | return 0; | |
2128 | } |