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