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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 | ||
a6b6e75e | 19 | #include <linux/sched.h> |
eb60ceac CM |
20 | #include "ctree.h" |
21 | #include "disk-io.h" | |
7f5c1516 | 22 | #include "transaction.h" |
5f39d397 | 23 | #include "print-tree.h" |
9a8dd150 | 24 | |
e089f05c CM |
25 | static int split_node(struct btrfs_trans_handle *trans, struct btrfs_root |
26 | *root, struct btrfs_path *path, int level); | |
27 | static int split_leaf(struct btrfs_trans_handle *trans, struct btrfs_root | |
d4dbff95 | 28 | *root, struct btrfs_key *ins_key, |
cc0c5538 | 29 | struct btrfs_path *path, int data_size, int extend); |
5f39d397 CM |
30 | static int push_node_left(struct btrfs_trans_handle *trans, |
31 | struct btrfs_root *root, struct extent_buffer *dst, | |
32 | struct extent_buffer *src); | |
33 | static int balance_node_right(struct btrfs_trans_handle *trans, | |
34 | struct btrfs_root *root, | |
35 | struct extent_buffer *dst_buf, | |
36 | struct extent_buffer *src_buf); | |
e089f05c CM |
37 | static int del_ptr(struct btrfs_trans_handle *trans, struct btrfs_root *root, |
38 | struct btrfs_path *path, int level, int slot); | |
d97e63b6 | 39 | |
df24a2b9 | 40 | inline void btrfs_init_path(struct btrfs_path *p) |
2c90e5d6 | 41 | { |
df24a2b9 | 42 | memset(p, 0, sizeof(*p)); |
2c90e5d6 CM |
43 | } |
44 | ||
df24a2b9 | 45 | struct btrfs_path *btrfs_alloc_path(void) |
2c90e5d6 | 46 | { |
df24a2b9 CM |
47 | struct btrfs_path *path; |
48 | path = kmem_cache_alloc(btrfs_path_cachep, GFP_NOFS); | |
2cc58cf2 | 49 | if (path) { |
df24a2b9 | 50 | btrfs_init_path(path); |
2cc58cf2 CM |
51 | path->reada = 1; |
52 | } | |
df24a2b9 | 53 | return path; |
2c90e5d6 CM |
54 | } |
55 | ||
df24a2b9 | 56 | void btrfs_free_path(struct btrfs_path *p) |
be0e5c09 | 57 | { |
df24a2b9 CM |
58 | btrfs_release_path(NULL, p); |
59 | kmem_cache_free(btrfs_path_cachep, p); | |
be0e5c09 CM |
60 | } |
61 | ||
234b63a0 | 62 | void btrfs_release_path(struct btrfs_root *root, struct btrfs_path *p) |
eb60ceac CM |
63 | { |
64 | int i; | |
234b63a0 | 65 | for (i = 0; i < BTRFS_MAX_LEVEL; i++) { |
eb60ceac CM |
66 | if (!p->nodes[i]) |
67 | break; | |
5f39d397 | 68 | free_extent_buffer(p->nodes[i]); |
eb60ceac | 69 | } |
aa5d6bed | 70 | memset(p, 0, sizeof(*p)); |
eb60ceac CM |
71 | } |
72 | ||
5f39d397 CM |
73 | static int __btrfs_cow_block(struct btrfs_trans_handle *trans, |
74 | struct btrfs_root *root, | |
75 | struct extent_buffer *buf, | |
76 | struct extent_buffer *parent, int parent_slot, | |
77 | struct extent_buffer **cow_ret, | |
78 | u64 search_start, u64 empty_size) | |
02217ed2 | 79 | { |
7bb86316 | 80 | u64 root_gen; |
5f39d397 | 81 | struct extent_buffer *cow; |
7bb86316 | 82 | u32 nritems; |
6702ed49 CM |
83 | int ret = 0; |
84 | int different_trans = 0; | |
7bb86316 CM |
85 | int level; |
86 | struct btrfs_key first_key; | |
87 | ||
88 | if (root->ref_cows) { | |
89 | root_gen = trans->transid; | |
90 | } else { | |
91 | root_gen = 0; | |
92 | } | |
02217ed2 | 93 | |
7bb86316 CM |
94 | WARN_ON(root->ref_cows && trans->transid != |
95 | root->fs_info->running_transaction->transid); | |
6702ed49 | 96 | WARN_ON(root->ref_cows && trans->transid != root->last_trans); |
5f39d397 | 97 | |
7bb86316 CM |
98 | level = btrfs_header_level(buf); |
99 | nritems = btrfs_header_nritems(buf); | |
100 | if (nritems) { | |
101 | if (level == 0) | |
102 | btrfs_item_key_to_cpu(buf, &first_key, 0); | |
103 | else | |
104 | btrfs_node_key_to_cpu(buf, &first_key, 0); | |
105 | } else { | |
106 | first_key.objectid = 0; | |
107 | } | |
108 | cow = __btrfs_alloc_free_block(trans, root, buf->len, | |
109 | root->root_key.objectid, | |
110 | root_gen, first_key.objectid, level, | |
db94535d | 111 | search_start, empty_size); |
54aa1f4d CM |
112 | if (IS_ERR(cow)) |
113 | return PTR_ERR(cow); | |
6702ed49 | 114 | |
5f39d397 | 115 | copy_extent_buffer(cow, buf, 0, 0, cow->len); |
db94535d | 116 | btrfs_set_header_bytenr(cow, cow->start); |
5f39d397 CM |
117 | btrfs_set_header_generation(cow, trans->transid); |
118 | btrfs_set_header_owner(cow, root->root_key.objectid); | |
6702ed49 | 119 | |
5f39d397 CM |
120 | WARN_ON(btrfs_header_generation(buf) > trans->transid); |
121 | if (btrfs_header_generation(buf) != trans->transid) { | |
6702ed49 CM |
122 | different_trans = 1; |
123 | ret = btrfs_inc_ref(trans, root, buf); | |
124 | if (ret) | |
125 | return ret; | |
126 | } else { | |
6702ed49 CM |
127 | clean_tree_block(trans, root, buf); |
128 | } | |
129 | ||
02217ed2 | 130 | if (buf == root->node) { |
7bb86316 | 131 | root_gen = btrfs_header_generation(buf); |
02217ed2 | 132 | root->node = cow; |
5f39d397 | 133 | extent_buffer_get(cow); |
2c90e5d6 | 134 | if (buf != root->commit_root) { |
db94535d | 135 | btrfs_free_extent(trans, root, buf->start, |
7bb86316 CM |
136 | buf->len, root->root_key.objectid, |
137 | root_gen, 0, 0, 1); | |
2c90e5d6 | 138 | } |
5f39d397 | 139 | free_extent_buffer(buf); |
02217ed2 | 140 | } else { |
7bb86316 | 141 | root_gen = btrfs_header_generation(parent); |
5f39d397 | 142 | btrfs_set_node_blockptr(parent, parent_slot, |
db94535d | 143 | cow->start); |
74493f7a CM |
144 | WARN_ON(trans->transid == 0); |
145 | btrfs_set_node_ptr_generation(parent, parent_slot, | |
146 | trans->transid); | |
d6025579 | 147 | btrfs_mark_buffer_dirty(parent); |
5f39d397 | 148 | WARN_ON(btrfs_header_generation(parent) != trans->transid); |
7bb86316 CM |
149 | btrfs_free_extent(trans, root, buf->start, buf->len, |
150 | btrfs_header_owner(parent), root_gen, | |
151 | 0, 0, 1); | |
02217ed2 | 152 | } |
5f39d397 | 153 | free_extent_buffer(buf); |
ccd467d6 | 154 | btrfs_mark_buffer_dirty(cow); |
2c90e5d6 | 155 | *cow_ret = cow; |
02217ed2 CM |
156 | return 0; |
157 | } | |
158 | ||
5f39d397 CM |
159 | int btrfs_cow_block(struct btrfs_trans_handle *trans, |
160 | struct btrfs_root *root, struct extent_buffer *buf, | |
161 | struct extent_buffer *parent, int parent_slot, | |
162 | struct extent_buffer **cow_ret) | |
6702ed49 CM |
163 | { |
164 | u64 search_start; | |
f510cfec | 165 | int ret; |
6702ed49 CM |
166 | if (trans->transaction != root->fs_info->running_transaction) { |
167 | printk(KERN_CRIT "trans %Lu running %Lu\n", trans->transid, | |
168 | root->fs_info->running_transaction->transid); | |
169 | WARN_ON(1); | |
170 | } | |
171 | if (trans->transid != root->fs_info->generation) { | |
172 | printk(KERN_CRIT "trans %Lu running %Lu\n", trans->transid, | |
173 | root->fs_info->generation); | |
174 | WARN_ON(1); | |
175 | } | |
5f39d397 | 176 | if (btrfs_header_generation(buf) == trans->transid) { |
6702ed49 CM |
177 | *cow_ret = buf; |
178 | return 0; | |
179 | } | |
180 | ||
db94535d | 181 | search_start = buf->start & ~((u64)BTRFS_BLOCK_GROUP_SIZE - 1); |
f510cfec | 182 | ret = __btrfs_cow_block(trans, root, buf, parent, |
6702ed49 | 183 | parent_slot, cow_ret, search_start, 0); |
f510cfec | 184 | return ret; |
6702ed49 CM |
185 | } |
186 | ||
6b80053d | 187 | static int close_blocks(u64 blocknr, u64 other, u32 blocksize) |
6702ed49 | 188 | { |
6b80053d | 189 | if (blocknr < other && other - (blocknr + blocksize) < 32768) |
6702ed49 | 190 | return 1; |
6b80053d | 191 | if (blocknr > other && blocknr - (other + blocksize) < 32768) |
6702ed49 CM |
192 | return 1; |
193 | return 0; | |
194 | } | |
195 | ||
081e9573 CM |
196 | /* |
197 | * compare two keys in a memcmp fashion | |
198 | */ | |
199 | static int comp_keys(struct btrfs_disk_key *disk, struct btrfs_key *k2) | |
200 | { | |
201 | struct btrfs_key k1; | |
202 | ||
203 | btrfs_disk_key_to_cpu(&k1, disk); | |
204 | ||
205 | if (k1.objectid > k2->objectid) | |
206 | return 1; | |
207 | if (k1.objectid < k2->objectid) | |
208 | return -1; | |
209 | if (k1.type > k2->type) | |
210 | return 1; | |
211 | if (k1.type < k2->type) | |
212 | return -1; | |
213 | if (k1.offset > k2->offset) | |
214 | return 1; | |
215 | if (k1.offset < k2->offset) | |
216 | return -1; | |
217 | return 0; | |
218 | } | |
219 | ||
220 | ||
6702ed49 | 221 | int btrfs_realloc_node(struct btrfs_trans_handle *trans, |
5f39d397 | 222 | struct btrfs_root *root, struct extent_buffer *parent, |
a6b6e75e CM |
223 | int start_slot, int cache_only, u64 *last_ret, |
224 | struct btrfs_key *progress) | |
6702ed49 | 225 | { |
6b80053d CM |
226 | struct extent_buffer *cur; |
227 | struct extent_buffer *tmp; | |
6702ed49 | 228 | u64 blocknr; |
e9d0b13b CM |
229 | u64 search_start = *last_ret; |
230 | u64 last_block = 0; | |
6702ed49 CM |
231 | u64 other; |
232 | u32 parent_nritems; | |
6702ed49 CM |
233 | int end_slot; |
234 | int i; | |
235 | int err = 0; | |
f2183bde | 236 | int parent_level; |
6b80053d CM |
237 | int uptodate; |
238 | u32 blocksize; | |
081e9573 CM |
239 | int progress_passed = 0; |
240 | struct btrfs_disk_key disk_key; | |
6702ed49 | 241 | |
5708b959 CM |
242 | parent_level = btrfs_header_level(parent); |
243 | if (cache_only && parent_level != 1) | |
244 | return 0; | |
245 | ||
6702ed49 CM |
246 | if (trans->transaction != root->fs_info->running_transaction) { |
247 | printk(KERN_CRIT "trans %Lu running %Lu\n", trans->transid, | |
248 | root->fs_info->running_transaction->transid); | |
249 | WARN_ON(1); | |
250 | } | |
251 | if (trans->transid != root->fs_info->generation) { | |
252 | printk(KERN_CRIT "trans %Lu running %Lu\n", trans->transid, | |
253 | root->fs_info->generation); | |
254 | WARN_ON(1); | |
255 | } | |
86479a04 | 256 | |
6b80053d | 257 | parent_nritems = btrfs_header_nritems(parent); |
6b80053d | 258 | blocksize = btrfs_level_size(root, parent_level - 1); |
6702ed49 CM |
259 | end_slot = parent_nritems; |
260 | ||
261 | if (parent_nritems == 1) | |
262 | return 0; | |
263 | ||
264 | for (i = start_slot; i < end_slot; i++) { | |
265 | int close = 1; | |
a6b6e75e | 266 | |
5708b959 CM |
267 | if (!parent->map_token) { |
268 | map_extent_buffer(parent, | |
269 | btrfs_node_key_ptr_offset(i), | |
270 | sizeof(struct btrfs_key_ptr), | |
271 | &parent->map_token, &parent->kaddr, | |
272 | &parent->map_start, &parent->map_len, | |
273 | KM_USER1); | |
274 | } | |
081e9573 CM |
275 | btrfs_node_key(parent, &disk_key, i); |
276 | if (!progress_passed && comp_keys(&disk_key, progress) < 0) | |
277 | continue; | |
278 | ||
279 | progress_passed = 1; | |
6b80053d | 280 | blocknr = btrfs_node_blockptr(parent, i); |
e9d0b13b CM |
281 | if (last_block == 0) |
282 | last_block = blocknr; | |
5708b959 | 283 | |
6702ed49 | 284 | if (i > 0) { |
6b80053d CM |
285 | other = btrfs_node_blockptr(parent, i - 1); |
286 | close = close_blocks(blocknr, other, blocksize); | |
6702ed49 | 287 | } |
5708b959 | 288 | if (close && i < end_slot - 2) { |
6b80053d CM |
289 | other = btrfs_node_blockptr(parent, i + 1); |
290 | close = close_blocks(blocknr, other, blocksize); | |
6702ed49 | 291 | } |
e9d0b13b CM |
292 | if (close) { |
293 | last_block = blocknr; | |
6702ed49 | 294 | continue; |
e9d0b13b | 295 | } |
5708b959 CM |
296 | if (parent->map_token) { |
297 | unmap_extent_buffer(parent, parent->map_token, | |
298 | KM_USER1); | |
299 | parent->map_token = NULL; | |
300 | } | |
6702ed49 | 301 | |
6b80053d CM |
302 | cur = btrfs_find_tree_block(root, blocknr, blocksize); |
303 | if (cur) | |
304 | uptodate = btrfs_buffer_uptodate(cur); | |
305 | else | |
306 | uptodate = 0; | |
5708b959 | 307 | if (!cur || !uptodate) { |
6702ed49 | 308 | if (cache_only) { |
6b80053d | 309 | free_extent_buffer(cur); |
6702ed49 CM |
310 | continue; |
311 | } | |
6b80053d CM |
312 | if (!cur) { |
313 | cur = read_tree_block(root, blocknr, | |
314 | blocksize); | |
315 | } else if (!uptodate) { | |
316 | btrfs_read_buffer(cur); | |
f2183bde | 317 | } |
6702ed49 | 318 | } |
e9d0b13b | 319 | if (search_start == 0) |
6b80053d | 320 | search_start = last_block; |
e9d0b13b | 321 | |
6b80053d CM |
322 | err = __btrfs_cow_block(trans, root, cur, parent, i, |
323 | &tmp, search_start, | |
324 | min(16 * blocksize, | |
325 | (end_slot - i) * blocksize)); | |
252c38f0 | 326 | if (err) { |
6b80053d | 327 | free_extent_buffer(cur); |
6702ed49 | 328 | break; |
252c38f0 | 329 | } |
6b80053d | 330 | search_start = tmp->start; |
5708b959 | 331 | last_block = tmp->start; |
f2183bde CM |
332 | *last_ret = search_start; |
333 | if (parent_level == 1) | |
6b80053d | 334 | btrfs_clear_buffer_defrag(tmp); |
6b80053d | 335 | free_extent_buffer(tmp); |
6702ed49 | 336 | } |
5708b959 CM |
337 | if (parent->map_token) { |
338 | unmap_extent_buffer(parent, parent->map_token, | |
339 | KM_USER1); | |
340 | parent->map_token = NULL; | |
341 | } | |
6702ed49 CM |
342 | return err; |
343 | } | |
344 | ||
74123bd7 CM |
345 | /* |
346 | * The leaf data grows from end-to-front in the node. | |
347 | * this returns the address of the start of the last item, | |
348 | * which is the stop of the leaf data stack | |
349 | */ | |
123abc88 | 350 | static inline unsigned int leaf_data_end(struct btrfs_root *root, |
5f39d397 | 351 | struct extent_buffer *leaf) |
be0e5c09 | 352 | { |
5f39d397 | 353 | u32 nr = btrfs_header_nritems(leaf); |
be0e5c09 | 354 | if (nr == 0) |
123abc88 | 355 | return BTRFS_LEAF_DATA_SIZE(root); |
5f39d397 | 356 | return btrfs_item_offset_nr(leaf, nr - 1); |
be0e5c09 CM |
357 | } |
358 | ||
123abc88 CM |
359 | static int check_node(struct btrfs_root *root, struct btrfs_path *path, |
360 | int level) | |
aa5d6bed | 361 | { |
5f39d397 CM |
362 | struct extent_buffer *parent = NULL; |
363 | struct extent_buffer *node = path->nodes[level]; | |
364 | struct btrfs_disk_key parent_key; | |
365 | struct btrfs_disk_key node_key; | |
aa5d6bed | 366 | int parent_slot; |
8d7be552 CM |
367 | int slot; |
368 | struct btrfs_key cpukey; | |
5f39d397 | 369 | u32 nritems = btrfs_header_nritems(node); |
aa5d6bed CM |
370 | |
371 | if (path->nodes[level + 1]) | |
5f39d397 | 372 | parent = path->nodes[level + 1]; |
a1f39630 | 373 | |
8d7be552 | 374 | slot = path->slots[level]; |
7518a238 CM |
375 | BUG_ON(nritems == 0); |
376 | if (parent) { | |
a1f39630 | 377 | parent_slot = path->slots[level + 1]; |
5f39d397 CM |
378 | btrfs_node_key(parent, &parent_key, parent_slot); |
379 | btrfs_node_key(node, &node_key, 0); | |
380 | BUG_ON(memcmp(&parent_key, &node_key, | |
e2fa7227 | 381 | sizeof(struct btrfs_disk_key))); |
1d4f8a0c | 382 | BUG_ON(btrfs_node_blockptr(parent, parent_slot) != |
db94535d | 383 | btrfs_header_bytenr(node)); |
aa5d6bed | 384 | } |
123abc88 | 385 | BUG_ON(nritems > BTRFS_NODEPTRS_PER_BLOCK(root)); |
8d7be552 | 386 | if (slot != 0) { |
5f39d397 CM |
387 | btrfs_node_key_to_cpu(node, &cpukey, slot - 1); |
388 | btrfs_node_key(node, &node_key, slot); | |
389 | BUG_ON(comp_keys(&node_key, &cpukey) <= 0); | |
8d7be552 CM |
390 | } |
391 | if (slot < nritems - 1) { | |
5f39d397 CM |
392 | btrfs_node_key_to_cpu(node, &cpukey, slot + 1); |
393 | btrfs_node_key(node, &node_key, slot); | |
394 | BUG_ON(comp_keys(&node_key, &cpukey) >= 0); | |
aa5d6bed CM |
395 | } |
396 | return 0; | |
397 | } | |
398 | ||
123abc88 CM |
399 | static int check_leaf(struct btrfs_root *root, struct btrfs_path *path, |
400 | int level) | |
aa5d6bed | 401 | { |
5f39d397 CM |
402 | struct extent_buffer *leaf = path->nodes[level]; |
403 | struct extent_buffer *parent = NULL; | |
aa5d6bed | 404 | int parent_slot; |
8d7be552 | 405 | struct btrfs_key cpukey; |
5f39d397 CM |
406 | struct btrfs_disk_key parent_key; |
407 | struct btrfs_disk_key leaf_key; | |
408 | int slot = path->slots[0]; | |
8d7be552 | 409 | |
5f39d397 | 410 | u32 nritems = btrfs_header_nritems(leaf); |
aa5d6bed CM |
411 | |
412 | if (path->nodes[level + 1]) | |
5f39d397 | 413 | parent = path->nodes[level + 1]; |
7518a238 CM |
414 | |
415 | if (nritems == 0) | |
416 | return 0; | |
417 | ||
418 | if (parent) { | |
a1f39630 | 419 | parent_slot = path->slots[level + 1]; |
5f39d397 CM |
420 | btrfs_node_key(parent, &parent_key, parent_slot); |
421 | btrfs_item_key(leaf, &leaf_key, 0); | |
6702ed49 | 422 | |
5f39d397 | 423 | BUG_ON(memcmp(&parent_key, &leaf_key, |
e2fa7227 | 424 | sizeof(struct btrfs_disk_key))); |
1d4f8a0c | 425 | BUG_ON(btrfs_node_blockptr(parent, parent_slot) != |
db94535d | 426 | btrfs_header_bytenr(leaf)); |
5f39d397 CM |
427 | } |
428 | #if 0 | |
429 | for (i = 0; nritems > 1 && i < nritems - 2; i++) { | |
430 | btrfs_item_key_to_cpu(leaf, &cpukey, i + 1); | |
431 | btrfs_item_key(leaf, &leaf_key, i); | |
432 | if (comp_keys(&leaf_key, &cpukey) >= 0) { | |
433 | btrfs_print_leaf(root, leaf); | |
434 | printk("slot %d offset bad key\n", i); | |
435 | BUG_ON(1); | |
436 | } | |
437 | if (btrfs_item_offset_nr(leaf, i) != | |
438 | btrfs_item_end_nr(leaf, i + 1)) { | |
439 | btrfs_print_leaf(root, leaf); | |
440 | printk("slot %d offset bad\n", i); | |
441 | BUG_ON(1); | |
442 | } | |
443 | if (i == 0) { | |
444 | if (btrfs_item_offset_nr(leaf, i) + | |
445 | btrfs_item_size_nr(leaf, i) != | |
446 | BTRFS_LEAF_DATA_SIZE(root)) { | |
447 | btrfs_print_leaf(root, leaf); | |
448 | printk("slot %d first offset bad\n", i); | |
449 | BUG_ON(1); | |
450 | } | |
451 | } | |
aa5d6bed | 452 | } |
5f39d397 CM |
453 | if (nritems > 0) { |
454 | if (btrfs_item_size_nr(leaf, nritems - 1) > 4096) { | |
455 | btrfs_print_leaf(root, leaf); | |
456 | printk("slot %d bad size \n", nritems - 1); | |
457 | BUG_ON(1); | |
458 | } | |
459 | } | |
460 | #endif | |
461 | if (slot != 0 && slot < nritems - 1) { | |
462 | btrfs_item_key(leaf, &leaf_key, slot); | |
463 | btrfs_item_key_to_cpu(leaf, &cpukey, slot - 1); | |
464 | if (comp_keys(&leaf_key, &cpukey) <= 0) { | |
465 | btrfs_print_leaf(root, leaf); | |
466 | printk("slot %d offset bad key\n", slot); | |
467 | BUG_ON(1); | |
468 | } | |
469 | if (btrfs_item_offset_nr(leaf, slot - 1) != | |
470 | btrfs_item_end_nr(leaf, slot)) { | |
471 | btrfs_print_leaf(root, leaf); | |
472 | printk("slot %d offset bad\n", slot); | |
473 | BUG_ON(1); | |
474 | } | |
8d7be552 CM |
475 | } |
476 | if (slot < nritems - 1) { | |
5f39d397 CM |
477 | btrfs_item_key(leaf, &leaf_key, slot); |
478 | btrfs_item_key_to_cpu(leaf, &cpukey, slot + 1); | |
479 | BUG_ON(comp_keys(&leaf_key, &cpukey) >= 0); | |
480 | if (btrfs_item_offset_nr(leaf, slot) != | |
481 | btrfs_item_end_nr(leaf, slot + 1)) { | |
482 | btrfs_print_leaf(root, leaf); | |
483 | printk("slot %d offset bad\n", slot); | |
484 | BUG_ON(1); | |
485 | } | |
aa5d6bed | 486 | } |
5f39d397 CM |
487 | BUG_ON(btrfs_item_offset_nr(leaf, 0) + |
488 | btrfs_item_size_nr(leaf, 0) != BTRFS_LEAF_DATA_SIZE(root)); | |
aa5d6bed CM |
489 | return 0; |
490 | } | |
491 | ||
123abc88 CM |
492 | static int check_block(struct btrfs_root *root, struct btrfs_path *path, |
493 | int level) | |
aa5d6bed | 494 | { |
810191ff | 495 | return 0; |
db94535d | 496 | #if 0 |
5f39d397 | 497 | struct extent_buffer *buf = path->nodes[level]; |
5f39d397 | 498 | |
479965d6 CM |
499 | if (memcmp_extent_buffer(buf, root->fs_info->fsid, |
500 | (unsigned long)btrfs_header_fsid(buf), | |
501 | BTRFS_FSID_SIZE)) { | |
5f39d397 | 502 | printk("warning bad block %Lu\n", buf->start); |
db94535d | 503 | return 1; |
5f39d397 | 504 | } |
db94535d | 505 | #endif |
aa5d6bed | 506 | if (level == 0) |
123abc88 CM |
507 | return check_leaf(root, path, level); |
508 | return check_node(root, path, level); | |
aa5d6bed CM |
509 | } |
510 | ||
74123bd7 | 511 | /* |
5f39d397 CM |
512 | * search for key in the extent_buffer. The items start at offset p, |
513 | * and they are item_size apart. There are 'max' items in p. | |
514 | * | |
74123bd7 CM |
515 | * the slot in the array is returned via slot, and it points to |
516 | * the place where you would insert key if it is not found in | |
517 | * the array. | |
518 | * | |
519 | * slot may point to max if the key is bigger than all of the keys | |
520 | */ | |
5f39d397 CM |
521 | static int generic_bin_search(struct extent_buffer *eb, unsigned long p, |
522 | int item_size, struct btrfs_key *key, | |
523 | int max, int *slot) | |
be0e5c09 CM |
524 | { |
525 | int low = 0; | |
526 | int high = max; | |
527 | int mid; | |
528 | int ret; | |
479965d6 | 529 | struct btrfs_disk_key *tmp = NULL; |
5f39d397 CM |
530 | struct btrfs_disk_key unaligned; |
531 | unsigned long offset; | |
532 | char *map_token = NULL; | |
533 | char *kaddr = NULL; | |
534 | unsigned long map_start = 0; | |
535 | unsigned long map_len = 0; | |
479965d6 | 536 | int err; |
be0e5c09 CM |
537 | |
538 | while(low < high) { | |
539 | mid = (low + high) / 2; | |
5f39d397 CM |
540 | offset = p + mid * item_size; |
541 | ||
542 | if (!map_token || offset < map_start || | |
543 | (offset + sizeof(struct btrfs_disk_key)) > | |
544 | map_start + map_len) { | |
479965d6 | 545 | if (map_token) { |
5f39d397 | 546 | unmap_extent_buffer(eb, map_token, KM_USER0); |
479965d6 CM |
547 | map_token = NULL; |
548 | } | |
549 | err = map_extent_buffer(eb, offset, | |
550 | sizeof(struct btrfs_disk_key), | |
551 | &map_token, &kaddr, | |
552 | &map_start, &map_len, KM_USER0); | |
553 | ||
554 | if (!err) { | |
555 | tmp = (struct btrfs_disk_key *)(kaddr + offset - | |
556 | map_start); | |
557 | } else { | |
558 | read_extent_buffer(eb, &unaligned, | |
559 | offset, sizeof(unaligned)); | |
560 | tmp = &unaligned; | |
561 | } | |
5f39d397 | 562 | |
5f39d397 CM |
563 | } else { |
564 | tmp = (struct btrfs_disk_key *)(kaddr + offset - | |
565 | map_start); | |
566 | } | |
be0e5c09 CM |
567 | ret = comp_keys(tmp, key); |
568 | ||
569 | if (ret < 0) | |
570 | low = mid + 1; | |
571 | else if (ret > 0) | |
572 | high = mid; | |
573 | else { | |
574 | *slot = mid; | |
479965d6 CM |
575 | if (map_token) |
576 | unmap_extent_buffer(eb, map_token, KM_USER0); | |
be0e5c09 CM |
577 | return 0; |
578 | } | |
579 | } | |
580 | *slot = low; | |
5f39d397 CM |
581 | if (map_token) |
582 | unmap_extent_buffer(eb, map_token, KM_USER0); | |
be0e5c09 CM |
583 | return 1; |
584 | } | |
585 | ||
97571fd0 CM |
586 | /* |
587 | * simple bin_search frontend that does the right thing for | |
588 | * leaves vs nodes | |
589 | */ | |
5f39d397 CM |
590 | static int bin_search(struct extent_buffer *eb, struct btrfs_key *key, |
591 | int level, int *slot) | |
be0e5c09 | 592 | { |
5f39d397 CM |
593 | if (level == 0) { |
594 | return generic_bin_search(eb, | |
595 | offsetof(struct btrfs_leaf, items), | |
0783fcfc | 596 | sizeof(struct btrfs_item), |
5f39d397 | 597 | key, btrfs_header_nritems(eb), |
7518a238 | 598 | slot); |
be0e5c09 | 599 | } else { |
5f39d397 CM |
600 | return generic_bin_search(eb, |
601 | offsetof(struct btrfs_node, ptrs), | |
123abc88 | 602 | sizeof(struct btrfs_key_ptr), |
5f39d397 | 603 | key, btrfs_header_nritems(eb), |
7518a238 | 604 | slot); |
be0e5c09 CM |
605 | } |
606 | return -1; | |
607 | } | |
608 | ||
5f39d397 CM |
609 | static struct extent_buffer *read_node_slot(struct btrfs_root *root, |
610 | struct extent_buffer *parent, int slot) | |
bb803951 | 611 | { |
bb803951 CM |
612 | if (slot < 0) |
613 | return NULL; | |
5f39d397 | 614 | if (slot >= btrfs_header_nritems(parent)) |
bb803951 | 615 | return NULL; |
db94535d CM |
616 | return read_tree_block(root, btrfs_node_blockptr(parent, slot), |
617 | btrfs_level_size(root, btrfs_header_level(parent) - 1)); | |
bb803951 CM |
618 | } |
619 | ||
e089f05c CM |
620 | static int balance_level(struct btrfs_trans_handle *trans, struct btrfs_root |
621 | *root, struct btrfs_path *path, int level) | |
bb803951 | 622 | { |
5f39d397 CM |
623 | struct extent_buffer *right = NULL; |
624 | struct extent_buffer *mid; | |
625 | struct extent_buffer *left = NULL; | |
626 | struct extent_buffer *parent = NULL; | |
bb803951 CM |
627 | int ret = 0; |
628 | int wret; | |
629 | int pslot; | |
bb803951 | 630 | int orig_slot = path->slots[level]; |
54aa1f4d | 631 | int err_on_enospc = 0; |
79f95c82 | 632 | u64 orig_ptr; |
bb803951 CM |
633 | |
634 | if (level == 0) | |
635 | return 0; | |
636 | ||
5f39d397 | 637 | mid = path->nodes[level]; |
7bb86316 CM |
638 | WARN_ON(btrfs_header_generation(mid) != trans->transid); |
639 | ||
1d4f8a0c | 640 | orig_ptr = btrfs_node_blockptr(mid, orig_slot); |
79f95c82 | 641 | |
234b63a0 | 642 | if (level < BTRFS_MAX_LEVEL - 1) |
5f39d397 | 643 | parent = path->nodes[level + 1]; |
bb803951 CM |
644 | pslot = path->slots[level + 1]; |
645 | ||
40689478 CM |
646 | /* |
647 | * deal with the case where there is only one pointer in the root | |
648 | * by promoting the node below to a root | |
649 | */ | |
5f39d397 CM |
650 | if (!parent) { |
651 | struct extent_buffer *child; | |
bb803951 | 652 | |
5f39d397 | 653 | if (btrfs_header_nritems(mid) != 1) |
bb803951 CM |
654 | return 0; |
655 | ||
656 | /* promote the child to a root */ | |
5f39d397 | 657 | child = read_node_slot(root, mid, 0); |
bb803951 CM |
658 | BUG_ON(!child); |
659 | root->node = child; | |
660 | path->nodes[level] = NULL; | |
5f39d397 CM |
661 | clean_tree_block(trans, root, mid); |
662 | wait_on_tree_block_writeback(root, mid); | |
bb803951 | 663 | /* once for the path */ |
5f39d397 | 664 | free_extent_buffer(mid); |
7bb86316 CM |
665 | ret = btrfs_free_extent(trans, root, mid->start, mid->len, |
666 | root->root_key.objectid, | |
667 | btrfs_header_generation(mid), 0, 0, 1); | |
bb803951 | 668 | /* once for the root ptr */ |
5f39d397 | 669 | free_extent_buffer(mid); |
db94535d | 670 | return ret; |
bb803951 | 671 | } |
5f39d397 | 672 | if (btrfs_header_nritems(mid) > |
123abc88 | 673 | BTRFS_NODEPTRS_PER_BLOCK(root) / 4) |
bb803951 CM |
674 | return 0; |
675 | ||
5f39d397 | 676 | if (btrfs_header_nritems(mid) < 2) |
54aa1f4d CM |
677 | err_on_enospc = 1; |
678 | ||
5f39d397 CM |
679 | left = read_node_slot(root, parent, pslot - 1); |
680 | if (left) { | |
681 | wret = btrfs_cow_block(trans, root, left, | |
682 | parent, pslot - 1, &left); | |
54aa1f4d CM |
683 | if (wret) { |
684 | ret = wret; | |
685 | goto enospc; | |
686 | } | |
2cc58cf2 | 687 | } |
5f39d397 CM |
688 | right = read_node_slot(root, parent, pslot + 1); |
689 | if (right) { | |
690 | wret = btrfs_cow_block(trans, root, right, | |
691 | parent, pslot + 1, &right); | |
2cc58cf2 CM |
692 | if (wret) { |
693 | ret = wret; | |
694 | goto enospc; | |
695 | } | |
696 | } | |
697 | ||
698 | /* first, try to make some room in the middle buffer */ | |
5f39d397 CM |
699 | if (left) { |
700 | orig_slot += btrfs_header_nritems(left); | |
701 | wret = push_node_left(trans, root, left, mid); | |
79f95c82 CM |
702 | if (wret < 0) |
703 | ret = wret; | |
5f39d397 | 704 | if (btrfs_header_nritems(mid) < 2) |
54aa1f4d | 705 | err_on_enospc = 1; |
bb803951 | 706 | } |
79f95c82 CM |
707 | |
708 | /* | |
709 | * then try to empty the right most buffer into the middle | |
710 | */ | |
5f39d397 CM |
711 | if (right) { |
712 | wret = push_node_left(trans, root, mid, right); | |
54aa1f4d | 713 | if (wret < 0 && wret != -ENOSPC) |
79f95c82 | 714 | ret = wret; |
5f39d397 | 715 | if (btrfs_header_nritems(right) == 0) { |
db94535d | 716 | u64 bytenr = right->start; |
7bb86316 | 717 | u64 generation = btrfs_header_generation(parent); |
db94535d CM |
718 | u32 blocksize = right->len; |
719 | ||
5f39d397 CM |
720 | clean_tree_block(trans, root, right); |
721 | wait_on_tree_block_writeback(root, right); | |
722 | free_extent_buffer(right); | |
bb803951 | 723 | right = NULL; |
e089f05c CM |
724 | wret = del_ptr(trans, root, path, level + 1, pslot + |
725 | 1); | |
bb803951 CM |
726 | if (wret) |
727 | ret = wret; | |
db94535d | 728 | wret = btrfs_free_extent(trans, root, bytenr, |
7bb86316 CM |
729 | blocksize, |
730 | btrfs_header_owner(parent), | |
731 | generation, 0, 0, 1); | |
bb803951 CM |
732 | if (wret) |
733 | ret = wret; | |
734 | } else { | |
5f39d397 CM |
735 | struct btrfs_disk_key right_key; |
736 | btrfs_node_key(right, &right_key, 0); | |
737 | btrfs_set_node_key(parent, &right_key, pslot + 1); | |
738 | btrfs_mark_buffer_dirty(parent); | |
bb803951 CM |
739 | } |
740 | } | |
5f39d397 | 741 | if (btrfs_header_nritems(mid) == 1) { |
79f95c82 CM |
742 | /* |
743 | * we're not allowed to leave a node with one item in the | |
744 | * tree during a delete. A deletion from lower in the tree | |
745 | * could try to delete the only pointer in this node. | |
746 | * So, pull some keys from the left. | |
747 | * There has to be a left pointer at this point because | |
748 | * otherwise we would have pulled some pointers from the | |
749 | * right | |
750 | */ | |
5f39d397 CM |
751 | BUG_ON(!left); |
752 | wret = balance_node_right(trans, root, mid, left); | |
54aa1f4d | 753 | if (wret < 0) { |
79f95c82 | 754 | ret = wret; |
54aa1f4d CM |
755 | goto enospc; |
756 | } | |
79f95c82 CM |
757 | BUG_ON(wret == 1); |
758 | } | |
5f39d397 | 759 | if (btrfs_header_nritems(mid) == 0) { |
79f95c82 | 760 | /* we've managed to empty the middle node, drop it */ |
7bb86316 | 761 | u64 root_gen = btrfs_header_generation(parent); |
db94535d CM |
762 | u64 bytenr = mid->start; |
763 | u32 blocksize = mid->len; | |
5f39d397 CM |
764 | clean_tree_block(trans, root, mid); |
765 | wait_on_tree_block_writeback(root, mid); | |
766 | free_extent_buffer(mid); | |
bb803951 | 767 | mid = NULL; |
e089f05c | 768 | wret = del_ptr(trans, root, path, level + 1, pslot); |
bb803951 CM |
769 | if (wret) |
770 | ret = wret; | |
7bb86316 CM |
771 | wret = btrfs_free_extent(trans, root, bytenr, blocksize, |
772 | btrfs_header_owner(parent), | |
773 | root_gen, 0, 0, 1); | |
bb803951 CM |
774 | if (wret) |
775 | ret = wret; | |
79f95c82 CM |
776 | } else { |
777 | /* update the parent key to reflect our changes */ | |
5f39d397 CM |
778 | struct btrfs_disk_key mid_key; |
779 | btrfs_node_key(mid, &mid_key, 0); | |
780 | btrfs_set_node_key(parent, &mid_key, pslot); | |
781 | btrfs_mark_buffer_dirty(parent); | |
79f95c82 | 782 | } |
bb803951 | 783 | |
79f95c82 | 784 | /* update the path */ |
5f39d397 CM |
785 | if (left) { |
786 | if (btrfs_header_nritems(left) > orig_slot) { | |
787 | extent_buffer_get(left); | |
788 | path->nodes[level] = left; | |
bb803951 CM |
789 | path->slots[level + 1] -= 1; |
790 | path->slots[level] = orig_slot; | |
5f39d397 CM |
791 | if (mid) |
792 | free_extent_buffer(mid); | |
bb803951 | 793 | } else { |
5f39d397 | 794 | orig_slot -= btrfs_header_nritems(left); |
bb803951 CM |
795 | path->slots[level] = orig_slot; |
796 | } | |
797 | } | |
79f95c82 | 798 | /* double check we haven't messed things up */ |
123abc88 | 799 | check_block(root, path, level); |
e20d96d6 | 800 | if (orig_ptr != |
5f39d397 | 801 | btrfs_node_blockptr(path->nodes[level], path->slots[level])) |
79f95c82 | 802 | BUG(); |
54aa1f4d | 803 | enospc: |
5f39d397 CM |
804 | if (right) |
805 | free_extent_buffer(right); | |
806 | if (left) | |
807 | free_extent_buffer(left); | |
bb803951 CM |
808 | return ret; |
809 | } | |
810 | ||
e66f709b CM |
811 | /* returns zero if the push worked, non-zero otherwise */ |
812 | static int push_nodes_for_insert(struct btrfs_trans_handle *trans, | |
813 | struct btrfs_root *root, | |
814 | struct btrfs_path *path, int level) | |
815 | { | |
5f39d397 CM |
816 | struct extent_buffer *right = NULL; |
817 | struct extent_buffer *mid; | |
818 | struct extent_buffer *left = NULL; | |
819 | struct extent_buffer *parent = NULL; | |
e66f709b CM |
820 | int ret = 0; |
821 | int wret; | |
822 | int pslot; | |
823 | int orig_slot = path->slots[level]; | |
824 | u64 orig_ptr; | |
825 | ||
826 | if (level == 0) | |
827 | return 1; | |
828 | ||
5f39d397 | 829 | mid = path->nodes[level]; |
7bb86316 | 830 | WARN_ON(btrfs_header_generation(mid) != trans->transid); |
e66f709b CM |
831 | orig_ptr = btrfs_node_blockptr(mid, orig_slot); |
832 | ||
833 | if (level < BTRFS_MAX_LEVEL - 1) | |
5f39d397 | 834 | parent = path->nodes[level + 1]; |
e66f709b CM |
835 | pslot = path->slots[level + 1]; |
836 | ||
5f39d397 | 837 | if (!parent) |
e66f709b | 838 | return 1; |
e66f709b | 839 | |
5f39d397 | 840 | left = read_node_slot(root, parent, pslot - 1); |
e66f709b CM |
841 | |
842 | /* first, try to make some room in the middle buffer */ | |
5f39d397 | 843 | if (left) { |
e66f709b | 844 | u32 left_nr; |
5f39d397 | 845 | left_nr = btrfs_header_nritems(left); |
33ade1f8 CM |
846 | if (left_nr >= BTRFS_NODEPTRS_PER_BLOCK(root) - 1) { |
847 | wret = 1; | |
848 | } else { | |
5f39d397 CM |
849 | ret = btrfs_cow_block(trans, root, left, parent, |
850 | pslot - 1, &left); | |
54aa1f4d CM |
851 | if (ret) |
852 | wret = 1; | |
853 | else { | |
54aa1f4d | 854 | wret = push_node_left(trans, root, |
5f39d397 | 855 | left, mid); |
54aa1f4d | 856 | } |
33ade1f8 | 857 | } |
e66f709b CM |
858 | if (wret < 0) |
859 | ret = wret; | |
860 | if (wret == 0) { | |
5f39d397 | 861 | struct btrfs_disk_key disk_key; |
e66f709b | 862 | orig_slot += left_nr; |
5f39d397 CM |
863 | btrfs_node_key(mid, &disk_key, 0); |
864 | btrfs_set_node_key(parent, &disk_key, pslot); | |
865 | btrfs_mark_buffer_dirty(parent); | |
866 | if (btrfs_header_nritems(left) > orig_slot) { | |
867 | path->nodes[level] = left; | |
e66f709b CM |
868 | path->slots[level + 1] -= 1; |
869 | path->slots[level] = orig_slot; | |
5f39d397 | 870 | free_extent_buffer(mid); |
e66f709b CM |
871 | } else { |
872 | orig_slot -= | |
5f39d397 | 873 | btrfs_header_nritems(left); |
e66f709b | 874 | path->slots[level] = orig_slot; |
5f39d397 | 875 | free_extent_buffer(left); |
e66f709b | 876 | } |
e66f709b CM |
877 | return 0; |
878 | } | |
5f39d397 | 879 | free_extent_buffer(left); |
e66f709b | 880 | } |
5f39d397 | 881 | right= read_node_slot(root, parent, pslot + 1); |
e66f709b CM |
882 | |
883 | /* | |
884 | * then try to empty the right most buffer into the middle | |
885 | */ | |
5f39d397 | 886 | if (right) { |
33ade1f8 | 887 | u32 right_nr; |
5f39d397 | 888 | right_nr = btrfs_header_nritems(right); |
33ade1f8 CM |
889 | if (right_nr >= BTRFS_NODEPTRS_PER_BLOCK(root) - 1) { |
890 | wret = 1; | |
891 | } else { | |
5f39d397 CM |
892 | ret = btrfs_cow_block(trans, root, right, |
893 | parent, pslot + 1, | |
894 | &right); | |
54aa1f4d CM |
895 | if (ret) |
896 | wret = 1; | |
897 | else { | |
54aa1f4d | 898 | wret = balance_node_right(trans, root, |
5f39d397 | 899 | right, mid); |
54aa1f4d | 900 | } |
33ade1f8 | 901 | } |
e66f709b CM |
902 | if (wret < 0) |
903 | ret = wret; | |
904 | if (wret == 0) { | |
5f39d397 CM |
905 | struct btrfs_disk_key disk_key; |
906 | ||
907 | btrfs_node_key(right, &disk_key, 0); | |
908 | btrfs_set_node_key(parent, &disk_key, pslot + 1); | |
909 | btrfs_mark_buffer_dirty(parent); | |
910 | ||
911 | if (btrfs_header_nritems(mid) <= orig_slot) { | |
912 | path->nodes[level] = right; | |
e66f709b CM |
913 | path->slots[level + 1] += 1; |
914 | path->slots[level] = orig_slot - | |
5f39d397 CM |
915 | btrfs_header_nritems(mid); |
916 | free_extent_buffer(mid); | |
e66f709b | 917 | } else { |
5f39d397 | 918 | free_extent_buffer(right); |
e66f709b | 919 | } |
e66f709b CM |
920 | return 0; |
921 | } | |
5f39d397 | 922 | free_extent_buffer(right); |
e66f709b | 923 | } |
e66f709b CM |
924 | return 1; |
925 | } | |
926 | ||
3c69faec CM |
927 | /* |
928 | * readahead one full node of leaves | |
929 | */ | |
930 | static void reada_for_search(struct btrfs_root *root, struct btrfs_path *path, | |
6702ed49 | 931 | int level, int slot) |
3c69faec | 932 | { |
5f39d397 | 933 | struct extent_buffer *node; |
3c69faec | 934 | u32 nritems; |
3c69faec | 935 | u64 search; |
6b80053d CM |
936 | u64 lowest_read; |
937 | u64 highest_read; | |
938 | u64 nread = 0; | |
3c69faec | 939 | int direction = path->reada; |
5f39d397 | 940 | struct extent_buffer *eb; |
6b80053d CM |
941 | u32 nr; |
942 | u32 blocksize; | |
943 | u32 nscan = 0; | |
db94535d | 944 | |
a6b6e75e | 945 | if (level != 1) |
6702ed49 CM |
946 | return; |
947 | ||
948 | if (!path->nodes[level]) | |
3c69faec CM |
949 | return; |
950 | ||
5f39d397 | 951 | node = path->nodes[level]; |
3c69faec | 952 | search = btrfs_node_blockptr(node, slot); |
6b80053d CM |
953 | blocksize = btrfs_level_size(root, level - 1); |
954 | eb = btrfs_find_tree_block(root, search, blocksize); | |
5f39d397 CM |
955 | if (eb) { |
956 | free_extent_buffer(eb); | |
3c69faec CM |
957 | return; |
958 | } | |
959 | ||
6b80053d CM |
960 | highest_read = search; |
961 | lowest_read = search; | |
962 | ||
5f39d397 | 963 | nritems = btrfs_header_nritems(node); |
6b80053d | 964 | nr = slot; |
3c69faec | 965 | while(1) { |
6b80053d CM |
966 | if (direction < 0) { |
967 | if (nr == 0) | |
968 | break; | |
969 | nr--; | |
970 | } else if (direction > 0) { | |
971 | nr++; | |
972 | if (nr >= nritems) | |
973 | break; | |
3c69faec | 974 | } |
6b80053d CM |
975 | search = btrfs_node_blockptr(node, nr); |
976 | if ((search >= lowest_read && search <= highest_read) || | |
977 | (search < lowest_read && lowest_read - search <= 32768) || | |
978 | (search > highest_read && search - highest_read <= 32768)) { | |
979 | readahead_tree_block(root, search, blocksize); | |
980 | nread += blocksize; | |
981 | } | |
982 | nscan++; | |
983 | if (path->reada < 2 && (nread > (256 * 1024) || nscan > 32)) | |
984 | break; | |
985 | if(nread > (1024 * 1024) || nscan > 128) | |
986 | break; | |
987 | ||
988 | if (search < lowest_read) | |
989 | lowest_read = search; | |
990 | if (search > highest_read) | |
991 | highest_read = search; | |
3c69faec CM |
992 | } |
993 | } | |
74123bd7 CM |
994 | /* |
995 | * look for key in the tree. path is filled in with nodes along the way | |
996 | * if key is found, we return zero and you can find the item in the leaf | |
997 | * level of the path (level 0) | |
998 | * | |
999 | * If the key isn't found, the path points to the slot where it should | |
aa5d6bed CM |
1000 | * be inserted, and 1 is returned. If there are other errors during the |
1001 | * search a negative error number is returned. | |
97571fd0 CM |
1002 | * |
1003 | * if ins_len > 0, nodes and leaves will be split as we walk down the | |
1004 | * tree. if ins_len < 0, nodes will be merged as we walk down the tree (if | |
1005 | * possible) | |
74123bd7 | 1006 | */ |
e089f05c CM |
1007 | int btrfs_search_slot(struct btrfs_trans_handle *trans, struct btrfs_root |
1008 | *root, struct btrfs_key *key, struct btrfs_path *p, int | |
1009 | ins_len, int cow) | |
be0e5c09 | 1010 | { |
5f39d397 | 1011 | struct extent_buffer *b; |
db94535d | 1012 | u64 bytenr; |
74493f7a | 1013 | u64 ptr_gen; |
be0e5c09 CM |
1014 | int slot; |
1015 | int ret; | |
1016 | int level; | |
3c69faec | 1017 | int should_reada = p->reada; |
9f3a7427 CM |
1018 | u8 lowest_level = 0; |
1019 | ||
6702ed49 CM |
1020 | lowest_level = p->lowest_level; |
1021 | WARN_ON(lowest_level && ins_len); | |
22b0ebda CM |
1022 | WARN_ON(p->nodes[0] != NULL); |
1023 | WARN_ON(!mutex_is_locked(&root->fs_info->fs_mutex)); | |
bb803951 CM |
1024 | again: |
1025 | b = root->node; | |
5f39d397 | 1026 | extent_buffer_get(b); |
eb60ceac | 1027 | while (b) { |
5f39d397 | 1028 | level = btrfs_header_level(b); |
02217ed2 CM |
1029 | if (cow) { |
1030 | int wret; | |
e20d96d6 CM |
1031 | wret = btrfs_cow_block(trans, root, b, |
1032 | p->nodes[level + 1], | |
1033 | p->slots[level + 1], | |
252c38f0 | 1034 | &b); |
54aa1f4d | 1035 | if (wret) { |
5f39d397 | 1036 | free_extent_buffer(b); |
54aa1f4d CM |
1037 | return wret; |
1038 | } | |
02217ed2 CM |
1039 | } |
1040 | BUG_ON(!cow && ins_len); | |
5f39d397 | 1041 | if (level != btrfs_header_level(b)) |
2c90e5d6 | 1042 | WARN_ON(1); |
5f39d397 | 1043 | level = btrfs_header_level(b); |
eb60ceac | 1044 | p->nodes[level] = b; |
123abc88 | 1045 | ret = check_block(root, p, level); |
aa5d6bed CM |
1046 | if (ret) |
1047 | return -1; | |
5f39d397 CM |
1048 | ret = bin_search(b, key, level, &slot); |
1049 | if (level != 0) { | |
be0e5c09 CM |
1050 | if (ret && slot > 0) |
1051 | slot -= 1; | |
1052 | p->slots[level] = slot; | |
5f39d397 | 1053 | if (ins_len > 0 && btrfs_header_nritems(b) >= |
d4dbff95 | 1054 | BTRFS_NODEPTRS_PER_BLOCK(root) - 1) { |
e089f05c | 1055 | int sret = split_node(trans, root, p, level); |
5c680ed6 CM |
1056 | BUG_ON(sret > 0); |
1057 | if (sret) | |
1058 | return sret; | |
1059 | b = p->nodes[level]; | |
5c680ed6 | 1060 | slot = p->slots[level]; |
bb803951 | 1061 | } else if (ins_len < 0) { |
e089f05c CM |
1062 | int sret = balance_level(trans, root, p, |
1063 | level); | |
bb803951 CM |
1064 | if (sret) |
1065 | return sret; | |
1066 | b = p->nodes[level]; | |
f510cfec CM |
1067 | if (!b) { |
1068 | btrfs_release_path(NULL, p); | |
bb803951 | 1069 | goto again; |
f510cfec | 1070 | } |
bb803951 | 1071 | slot = p->slots[level]; |
5f39d397 | 1072 | BUG_ON(btrfs_header_nritems(b) == 1); |
5c680ed6 | 1073 | } |
9f3a7427 CM |
1074 | /* this is only true while dropping a snapshot */ |
1075 | if (level == lowest_level) | |
1076 | break; | |
db94535d | 1077 | bytenr = btrfs_node_blockptr(b, slot); |
74493f7a | 1078 | ptr_gen = btrfs_node_ptr_generation(b, slot); |
6702ed49 CM |
1079 | if (should_reada) |
1080 | reada_for_search(root, p, level, slot); | |
db94535d CM |
1081 | b = read_tree_block(root, bytenr, |
1082 | btrfs_level_size(root, level - 1)); | |
74493f7a CM |
1083 | if (ptr_gen != btrfs_header_generation(b)) { |
1084 | printk("block %llu bad gen wanted %llu " | |
1085 | "found %llu\n", | |
1086 | (unsigned long long)b->start, | |
1087 | (unsigned long long)ptr_gen, | |
1088 | (unsigned long long)btrfs_header_generation(b)); | |
1089 | } | |
be0e5c09 CM |
1090 | } else { |
1091 | p->slots[level] = slot; | |
5f39d397 | 1092 | if (ins_len > 0 && btrfs_leaf_free_space(root, b) < |
0783fcfc | 1093 | sizeof(struct btrfs_item) + ins_len) { |
d4dbff95 | 1094 | int sret = split_leaf(trans, root, key, |
cc0c5538 | 1095 | p, ins_len, ret == 0); |
5c680ed6 CM |
1096 | BUG_ON(sret > 0); |
1097 | if (sret) | |
1098 | return sret; | |
1099 | } | |
be0e5c09 CM |
1100 | return ret; |
1101 | } | |
1102 | } | |
aa5d6bed | 1103 | return 1; |
be0e5c09 CM |
1104 | } |
1105 | ||
74123bd7 CM |
1106 | /* |
1107 | * adjust the pointers going up the tree, starting at level | |
1108 | * making sure the right key of each node is points to 'key'. | |
1109 | * This is used after shifting pointers to the left, so it stops | |
1110 | * fixing up pointers when a given leaf/node is not in slot 0 of the | |
1111 | * higher levels | |
aa5d6bed CM |
1112 | * |
1113 | * If this fails to write a tree block, it returns -1, but continues | |
1114 | * fixing up the blocks in ram so the tree is consistent. | |
74123bd7 | 1115 | */ |
5f39d397 CM |
1116 | static int fixup_low_keys(struct btrfs_trans_handle *trans, |
1117 | struct btrfs_root *root, struct btrfs_path *path, | |
1118 | struct btrfs_disk_key *key, int level) | |
be0e5c09 CM |
1119 | { |
1120 | int i; | |
aa5d6bed | 1121 | int ret = 0; |
5f39d397 CM |
1122 | struct extent_buffer *t; |
1123 | ||
234b63a0 | 1124 | for (i = level; i < BTRFS_MAX_LEVEL; i++) { |
be0e5c09 | 1125 | int tslot = path->slots[i]; |
eb60ceac | 1126 | if (!path->nodes[i]) |
be0e5c09 | 1127 | break; |
5f39d397 CM |
1128 | t = path->nodes[i]; |
1129 | btrfs_set_node_key(t, key, tslot); | |
d6025579 | 1130 | btrfs_mark_buffer_dirty(path->nodes[i]); |
be0e5c09 CM |
1131 | if (tslot != 0) |
1132 | break; | |
1133 | } | |
aa5d6bed | 1134 | return ret; |
be0e5c09 CM |
1135 | } |
1136 | ||
74123bd7 CM |
1137 | /* |
1138 | * try to push data from one node into the next node left in the | |
79f95c82 | 1139 | * tree. |
aa5d6bed CM |
1140 | * |
1141 | * returns 0 if some ptrs were pushed left, < 0 if there was some horrible | |
1142 | * error, and > 0 if there was no room in the left hand block. | |
74123bd7 | 1143 | */ |
e089f05c | 1144 | static int push_node_left(struct btrfs_trans_handle *trans, struct btrfs_root |
5f39d397 CM |
1145 | *root, struct extent_buffer *dst, |
1146 | struct extent_buffer *src) | |
be0e5c09 | 1147 | { |
be0e5c09 | 1148 | int push_items = 0; |
bb803951 CM |
1149 | int src_nritems; |
1150 | int dst_nritems; | |
aa5d6bed | 1151 | int ret = 0; |
be0e5c09 | 1152 | |
5f39d397 CM |
1153 | src_nritems = btrfs_header_nritems(src); |
1154 | dst_nritems = btrfs_header_nritems(dst); | |
123abc88 | 1155 | push_items = BTRFS_NODEPTRS_PER_BLOCK(root) - dst_nritems; |
7bb86316 CM |
1156 | WARN_ON(btrfs_header_generation(src) != trans->transid); |
1157 | WARN_ON(btrfs_header_generation(dst) != trans->transid); | |
54aa1f4d | 1158 | |
eb60ceac | 1159 | if (push_items <= 0) { |
be0e5c09 | 1160 | return 1; |
eb60ceac | 1161 | } |
be0e5c09 | 1162 | |
bb803951 | 1163 | if (src_nritems < push_items) |
79f95c82 CM |
1164 | push_items = src_nritems; |
1165 | ||
5f39d397 CM |
1166 | copy_extent_buffer(dst, src, |
1167 | btrfs_node_key_ptr_offset(dst_nritems), | |
1168 | btrfs_node_key_ptr_offset(0), | |
1169 | push_items * sizeof(struct btrfs_key_ptr)); | |
1170 | ||
bb803951 | 1171 | if (push_items < src_nritems) { |
5f39d397 CM |
1172 | memmove_extent_buffer(src, btrfs_node_key_ptr_offset(0), |
1173 | btrfs_node_key_ptr_offset(push_items), | |
1174 | (src_nritems - push_items) * | |
1175 | sizeof(struct btrfs_key_ptr)); | |
1176 | } | |
1177 | btrfs_set_header_nritems(src, src_nritems - push_items); | |
1178 | btrfs_set_header_nritems(dst, dst_nritems + push_items); | |
1179 | btrfs_mark_buffer_dirty(src); | |
1180 | btrfs_mark_buffer_dirty(dst); | |
79f95c82 CM |
1181 | return ret; |
1182 | } | |
1183 | ||
1184 | /* | |
1185 | * try to push data from one node into the next node right in the | |
1186 | * tree. | |
1187 | * | |
1188 | * returns 0 if some ptrs were pushed, < 0 if there was some horrible | |
1189 | * error, and > 0 if there was no room in the right hand block. | |
1190 | * | |
1191 | * this will only push up to 1/2 the contents of the left node over | |
1192 | */ | |
5f39d397 CM |
1193 | static int balance_node_right(struct btrfs_trans_handle *trans, |
1194 | struct btrfs_root *root, | |
1195 | struct extent_buffer *dst, | |
1196 | struct extent_buffer *src) | |
79f95c82 | 1197 | { |
79f95c82 CM |
1198 | int push_items = 0; |
1199 | int max_push; | |
1200 | int src_nritems; | |
1201 | int dst_nritems; | |
1202 | int ret = 0; | |
79f95c82 | 1203 | |
7bb86316 CM |
1204 | WARN_ON(btrfs_header_generation(src) != trans->transid); |
1205 | WARN_ON(btrfs_header_generation(dst) != trans->transid); | |
1206 | ||
5f39d397 CM |
1207 | src_nritems = btrfs_header_nritems(src); |
1208 | dst_nritems = btrfs_header_nritems(dst); | |
123abc88 | 1209 | push_items = BTRFS_NODEPTRS_PER_BLOCK(root) - dst_nritems; |
5f39d397 | 1210 | if (push_items <= 0) |
79f95c82 | 1211 | return 1; |
79f95c82 CM |
1212 | |
1213 | max_push = src_nritems / 2 + 1; | |
1214 | /* don't try to empty the node */ | |
252c38f0 | 1215 | if (max_push >= src_nritems) |
79f95c82 | 1216 | return 1; |
252c38f0 | 1217 | |
79f95c82 CM |
1218 | if (max_push < push_items) |
1219 | push_items = max_push; | |
1220 | ||
5f39d397 CM |
1221 | memmove_extent_buffer(dst, btrfs_node_key_ptr_offset(push_items), |
1222 | btrfs_node_key_ptr_offset(0), | |
1223 | (dst_nritems) * | |
1224 | sizeof(struct btrfs_key_ptr)); | |
d6025579 | 1225 | |
5f39d397 CM |
1226 | copy_extent_buffer(dst, src, |
1227 | btrfs_node_key_ptr_offset(0), | |
1228 | btrfs_node_key_ptr_offset(src_nritems - push_items), | |
1229 | push_items * sizeof(struct btrfs_key_ptr)); | |
79f95c82 | 1230 | |
5f39d397 CM |
1231 | btrfs_set_header_nritems(src, src_nritems - push_items); |
1232 | btrfs_set_header_nritems(dst, dst_nritems + push_items); | |
79f95c82 | 1233 | |
5f39d397 CM |
1234 | btrfs_mark_buffer_dirty(src); |
1235 | btrfs_mark_buffer_dirty(dst); | |
aa5d6bed | 1236 | return ret; |
be0e5c09 CM |
1237 | } |
1238 | ||
97571fd0 CM |
1239 | /* |
1240 | * helper function to insert a new root level in the tree. | |
1241 | * A new node is allocated, and a single item is inserted to | |
1242 | * point to the existing root | |
aa5d6bed CM |
1243 | * |
1244 | * returns zero on success or < 0 on failure. | |
97571fd0 | 1245 | */ |
5f39d397 CM |
1246 | static int insert_new_root(struct btrfs_trans_handle *trans, |
1247 | struct btrfs_root *root, | |
1248 | struct btrfs_path *path, int level) | |
5c680ed6 | 1249 | { |
7bb86316 CM |
1250 | u64 root_gen; |
1251 | u64 lower_gen; | |
5f39d397 CM |
1252 | struct extent_buffer *lower; |
1253 | struct extent_buffer *c; | |
1254 | struct btrfs_disk_key lower_key; | |
5c680ed6 CM |
1255 | |
1256 | BUG_ON(path->nodes[level]); | |
1257 | BUG_ON(path->nodes[level-1] != root->node); | |
1258 | ||
7bb86316 CM |
1259 | if (root->ref_cows) |
1260 | root_gen = trans->transid; | |
1261 | else | |
1262 | root_gen = 0; | |
1263 | ||
1264 | lower = path->nodes[level-1]; | |
1265 | if (level == 1) | |
1266 | btrfs_item_key(lower, &lower_key, 0); | |
1267 | else | |
1268 | btrfs_node_key(lower, &lower_key, 0); | |
1269 | ||
1270 | c = __btrfs_alloc_free_block(trans, root, root->nodesize, | |
1271 | root->root_key.objectid, | |
1272 | root_gen, lower_key.objectid, level, | |
db94535d | 1273 | root->node->start, 0); |
5f39d397 CM |
1274 | if (IS_ERR(c)) |
1275 | return PTR_ERR(c); | |
1276 | memset_extent_buffer(c, 0, 0, root->nodesize); | |
1277 | btrfs_set_header_nritems(c, 1); | |
1278 | btrfs_set_header_level(c, level); | |
db94535d | 1279 | btrfs_set_header_bytenr(c, c->start); |
5f39d397 CM |
1280 | btrfs_set_header_generation(c, trans->transid); |
1281 | btrfs_set_header_owner(c, root->root_key.objectid); | |
5f39d397 CM |
1282 | |
1283 | write_extent_buffer(c, root->fs_info->fsid, | |
1284 | (unsigned long)btrfs_header_fsid(c), | |
1285 | BTRFS_FSID_SIZE); | |
5f39d397 | 1286 | btrfs_set_node_key(c, &lower_key, 0); |
db94535d | 1287 | btrfs_set_node_blockptr(c, 0, lower->start); |
7bb86316 CM |
1288 | lower_gen = btrfs_header_generation(lower); |
1289 | WARN_ON(lower_gen == 0); | |
1290 | ||
1291 | btrfs_set_node_ptr_generation(c, 0, lower_gen); | |
d5719762 | 1292 | |
5f39d397 | 1293 | btrfs_mark_buffer_dirty(c); |
d5719762 | 1294 | |
5c680ed6 | 1295 | /* the super has an extra ref to root->node */ |
5f39d397 CM |
1296 | free_extent_buffer(root->node); |
1297 | root->node = c; | |
1298 | extent_buffer_get(c); | |
1299 | path->nodes[level] = c; | |
5c680ed6 | 1300 | path->slots[level] = 0; |
7bb86316 CM |
1301 | |
1302 | if (root->ref_cows && lower_gen != trans->transid) { | |
1303 | struct btrfs_path *back_path = btrfs_alloc_path(); | |
1304 | int ret; | |
1305 | ret = btrfs_insert_extent_backref(trans, | |
1306 | root->fs_info->extent_root, | |
1307 | path, lower->start, | |
1308 | root->root_key.objectid, | |
1309 | trans->transid, 0, 0); | |
1310 | BUG_ON(ret); | |
1311 | btrfs_free_path(back_path); | |
1312 | } | |
5c680ed6 CM |
1313 | return 0; |
1314 | } | |
1315 | ||
74123bd7 CM |
1316 | /* |
1317 | * worker function to insert a single pointer in a node. | |
1318 | * the node should have enough room for the pointer already | |
97571fd0 | 1319 | * |
74123bd7 CM |
1320 | * slot and level indicate where you want the key to go, and |
1321 | * blocknr is the block the key points to. | |
aa5d6bed CM |
1322 | * |
1323 | * returns zero on success and < 0 on any error | |
74123bd7 | 1324 | */ |
e089f05c CM |
1325 | static int insert_ptr(struct btrfs_trans_handle *trans, struct btrfs_root |
1326 | *root, struct btrfs_path *path, struct btrfs_disk_key | |
db94535d | 1327 | *key, u64 bytenr, int slot, int level) |
74123bd7 | 1328 | { |
5f39d397 | 1329 | struct extent_buffer *lower; |
74123bd7 | 1330 | int nritems; |
5c680ed6 CM |
1331 | |
1332 | BUG_ON(!path->nodes[level]); | |
5f39d397 CM |
1333 | lower = path->nodes[level]; |
1334 | nritems = btrfs_header_nritems(lower); | |
74123bd7 CM |
1335 | if (slot > nritems) |
1336 | BUG(); | |
123abc88 | 1337 | if (nritems == BTRFS_NODEPTRS_PER_BLOCK(root)) |
74123bd7 CM |
1338 | BUG(); |
1339 | if (slot != nritems) { | |
5f39d397 CM |
1340 | memmove_extent_buffer(lower, |
1341 | btrfs_node_key_ptr_offset(slot + 1), | |
1342 | btrfs_node_key_ptr_offset(slot), | |
d6025579 | 1343 | (nritems - slot) * sizeof(struct btrfs_key_ptr)); |
74123bd7 | 1344 | } |
5f39d397 | 1345 | btrfs_set_node_key(lower, key, slot); |
db94535d | 1346 | btrfs_set_node_blockptr(lower, slot, bytenr); |
74493f7a CM |
1347 | WARN_ON(trans->transid == 0); |
1348 | btrfs_set_node_ptr_generation(lower, slot, trans->transid); | |
5f39d397 CM |
1349 | btrfs_set_header_nritems(lower, nritems + 1); |
1350 | btrfs_mark_buffer_dirty(lower); | |
74123bd7 CM |
1351 | return 0; |
1352 | } | |
1353 | ||
97571fd0 CM |
1354 | /* |
1355 | * split the node at the specified level in path in two. | |
1356 | * The path is corrected to point to the appropriate node after the split | |
1357 | * | |
1358 | * Before splitting this tries to make some room in the node by pushing | |
1359 | * left and right, if either one works, it returns right away. | |
aa5d6bed CM |
1360 | * |
1361 | * returns 0 on success and < 0 on failure | |
97571fd0 | 1362 | */ |
e089f05c CM |
1363 | static int split_node(struct btrfs_trans_handle *trans, struct btrfs_root |
1364 | *root, struct btrfs_path *path, int level) | |
be0e5c09 | 1365 | { |
7bb86316 | 1366 | u64 root_gen; |
5f39d397 CM |
1367 | struct extent_buffer *c; |
1368 | struct extent_buffer *split; | |
1369 | struct btrfs_disk_key disk_key; | |
be0e5c09 | 1370 | int mid; |
5c680ed6 | 1371 | int ret; |
aa5d6bed | 1372 | int wret; |
7518a238 | 1373 | u32 c_nritems; |
eb60ceac | 1374 | |
5f39d397 | 1375 | c = path->nodes[level]; |
7bb86316 | 1376 | WARN_ON(btrfs_header_generation(c) != trans->transid); |
5f39d397 | 1377 | if (c == root->node) { |
5c680ed6 | 1378 | /* trying to split the root, lets make a new one */ |
e089f05c | 1379 | ret = insert_new_root(trans, root, path, level + 1); |
5c680ed6 CM |
1380 | if (ret) |
1381 | return ret; | |
e66f709b CM |
1382 | } else { |
1383 | ret = push_nodes_for_insert(trans, root, path, level); | |
5f39d397 CM |
1384 | c = path->nodes[level]; |
1385 | if (!ret && btrfs_header_nritems(c) < | |
e66f709b CM |
1386 | BTRFS_NODEPTRS_PER_BLOCK(root) - 1) |
1387 | return 0; | |
54aa1f4d CM |
1388 | if (ret < 0) |
1389 | return ret; | |
be0e5c09 | 1390 | } |
e66f709b | 1391 | |
5f39d397 | 1392 | c_nritems = btrfs_header_nritems(c); |
7bb86316 CM |
1393 | if (root->ref_cows) |
1394 | root_gen = trans->transid; | |
1395 | else | |
1396 | root_gen = 0; | |
1397 | ||
1398 | btrfs_node_key(c, &disk_key, 0); | |
1399 | split = __btrfs_alloc_free_block(trans, root, root->nodesize, | |
1400 | root->root_key.objectid, | |
1401 | root_gen, | |
1402 | btrfs_disk_key_objectid(&disk_key), | |
1403 | level, c->start, 0); | |
5f39d397 CM |
1404 | if (IS_ERR(split)) |
1405 | return PTR_ERR(split); | |
1406 | ||
1407 | btrfs_set_header_flags(split, btrfs_header_flags(c)); | |
1408 | btrfs_set_header_level(split, btrfs_header_level(c)); | |
db94535d | 1409 | btrfs_set_header_bytenr(split, split->start); |
5f39d397 CM |
1410 | btrfs_set_header_generation(split, trans->transid); |
1411 | btrfs_set_header_owner(split, root->root_key.objectid); | |
1412 | write_extent_buffer(split, root->fs_info->fsid, | |
1413 | (unsigned long)btrfs_header_fsid(split), | |
1414 | BTRFS_FSID_SIZE); | |
54aa1f4d | 1415 | |
7518a238 | 1416 | mid = (c_nritems + 1) / 2; |
5f39d397 CM |
1417 | |
1418 | copy_extent_buffer(split, c, | |
1419 | btrfs_node_key_ptr_offset(0), | |
1420 | btrfs_node_key_ptr_offset(mid), | |
1421 | (c_nritems - mid) * sizeof(struct btrfs_key_ptr)); | |
1422 | btrfs_set_header_nritems(split, c_nritems - mid); | |
1423 | btrfs_set_header_nritems(c, mid); | |
aa5d6bed CM |
1424 | ret = 0; |
1425 | ||
5f39d397 CM |
1426 | btrfs_mark_buffer_dirty(c); |
1427 | btrfs_mark_buffer_dirty(split); | |
1428 | ||
1429 | btrfs_node_key(split, &disk_key, 0); | |
db94535d | 1430 | wret = insert_ptr(trans, root, path, &disk_key, split->start, |
5f39d397 | 1431 | path->slots[level + 1] + 1, |
123abc88 | 1432 | level + 1); |
aa5d6bed CM |
1433 | if (wret) |
1434 | ret = wret; | |
1435 | ||
5de08d7d | 1436 | if (path->slots[level] >= mid) { |
5c680ed6 | 1437 | path->slots[level] -= mid; |
5f39d397 CM |
1438 | free_extent_buffer(c); |
1439 | path->nodes[level] = split; | |
5c680ed6 CM |
1440 | path->slots[level + 1] += 1; |
1441 | } else { | |
5f39d397 | 1442 | free_extent_buffer(split); |
be0e5c09 | 1443 | } |
aa5d6bed | 1444 | return ret; |
be0e5c09 CM |
1445 | } |
1446 | ||
74123bd7 CM |
1447 | /* |
1448 | * how many bytes are required to store the items in a leaf. start | |
1449 | * and nr indicate which items in the leaf to check. This totals up the | |
1450 | * space used both by the item structs and the item data | |
1451 | */ | |
5f39d397 | 1452 | static int leaf_space_used(struct extent_buffer *l, int start, int nr) |
be0e5c09 CM |
1453 | { |
1454 | int data_len; | |
5f39d397 | 1455 | int nritems = btrfs_header_nritems(l); |
d4dbff95 | 1456 | int end = min(nritems, start + nr) - 1; |
be0e5c09 CM |
1457 | |
1458 | if (!nr) | |
1459 | return 0; | |
5f39d397 CM |
1460 | data_len = btrfs_item_end_nr(l, start); |
1461 | data_len = data_len - btrfs_item_offset_nr(l, end); | |
0783fcfc | 1462 | data_len += sizeof(struct btrfs_item) * nr; |
d4dbff95 | 1463 | WARN_ON(data_len < 0); |
be0e5c09 CM |
1464 | return data_len; |
1465 | } | |
1466 | ||
d4dbff95 CM |
1467 | /* |
1468 | * The space between the end of the leaf items and | |
1469 | * the start of the leaf data. IOW, how much room | |
1470 | * the leaf has left for both items and data | |
1471 | */ | |
5f39d397 | 1472 | int btrfs_leaf_free_space(struct btrfs_root *root, struct extent_buffer *leaf) |
d4dbff95 | 1473 | { |
5f39d397 CM |
1474 | int nritems = btrfs_header_nritems(leaf); |
1475 | int ret; | |
1476 | ret = BTRFS_LEAF_DATA_SIZE(root) - leaf_space_used(leaf, 0, nritems); | |
1477 | if (ret < 0) { | |
1478 | printk("leaf free space ret %d, leaf data size %lu, used %d nritems %d\n", | |
ae2f5411 | 1479 | ret, (unsigned long) BTRFS_LEAF_DATA_SIZE(root), |
5f39d397 CM |
1480 | leaf_space_used(leaf, 0, nritems), nritems); |
1481 | } | |
1482 | return ret; | |
d4dbff95 CM |
1483 | } |
1484 | ||
00ec4c51 CM |
1485 | /* |
1486 | * push some data in the path leaf to the right, trying to free up at | |
1487 | * least data_size bytes. returns zero if the push worked, nonzero otherwise | |
aa5d6bed CM |
1488 | * |
1489 | * returns 1 if the push failed because the other node didn't have enough | |
1490 | * room, 0 if everything worked out and < 0 if there were major errors. | |
00ec4c51 | 1491 | */ |
e089f05c | 1492 | static int push_leaf_right(struct btrfs_trans_handle *trans, struct btrfs_root |
34a38218 CM |
1493 | *root, struct btrfs_path *path, int data_size, |
1494 | int empty) | |
00ec4c51 | 1495 | { |
5f39d397 CM |
1496 | struct extent_buffer *left = path->nodes[0]; |
1497 | struct extent_buffer *right; | |
1498 | struct extent_buffer *upper; | |
1499 | struct btrfs_disk_key disk_key; | |
00ec4c51 | 1500 | int slot; |
34a38218 | 1501 | u32 i; |
00ec4c51 CM |
1502 | int free_space; |
1503 | int push_space = 0; | |
1504 | int push_items = 0; | |
0783fcfc | 1505 | struct btrfs_item *item; |
7518a238 | 1506 | u32 left_nritems; |
34a38218 | 1507 | u32 nr; |
7518a238 | 1508 | u32 right_nritems; |
5f39d397 | 1509 | u32 data_end; |
db94535d | 1510 | u32 this_item_size; |
54aa1f4d | 1511 | int ret; |
00ec4c51 CM |
1512 | |
1513 | slot = path->slots[1]; | |
1514 | if (!path->nodes[1]) { | |
1515 | return 1; | |
1516 | } | |
1517 | upper = path->nodes[1]; | |
5f39d397 | 1518 | if (slot >= btrfs_header_nritems(upper) - 1) |
00ec4c51 | 1519 | return 1; |
5f39d397 | 1520 | |
db94535d CM |
1521 | right = read_tree_block(root, btrfs_node_blockptr(upper, slot + 1), |
1522 | root->leafsize); | |
123abc88 | 1523 | free_space = btrfs_leaf_free_space(root, right); |
0783fcfc | 1524 | if (free_space < data_size + sizeof(struct btrfs_item)) { |
5f39d397 | 1525 | free_extent_buffer(right); |
00ec4c51 CM |
1526 | return 1; |
1527 | } | |
5f39d397 | 1528 | |
02217ed2 | 1529 | /* cow and double check */ |
5f39d397 CM |
1530 | ret = btrfs_cow_block(trans, root, right, upper, |
1531 | slot + 1, &right); | |
54aa1f4d | 1532 | if (ret) { |
5f39d397 | 1533 | free_extent_buffer(right); |
54aa1f4d CM |
1534 | return 1; |
1535 | } | |
123abc88 | 1536 | free_space = btrfs_leaf_free_space(root, right); |
0783fcfc | 1537 | if (free_space < data_size + sizeof(struct btrfs_item)) { |
5f39d397 | 1538 | free_extent_buffer(right); |
02217ed2 CM |
1539 | return 1; |
1540 | } | |
1541 | ||
5f39d397 | 1542 | left_nritems = btrfs_header_nritems(left); |
a429e513 | 1543 | if (left_nritems == 0) { |
5f39d397 | 1544 | free_extent_buffer(right); |
a429e513 CM |
1545 | return 1; |
1546 | } | |
5f39d397 | 1547 | |
34a38218 CM |
1548 | if (empty) |
1549 | nr = 0; | |
1550 | else | |
1551 | nr = 1; | |
1552 | ||
1553 | i = left_nritems - 1; | |
1554 | while (i >= nr) { | |
5f39d397 | 1555 | item = btrfs_item_nr(left, i); |
db94535d | 1556 | |
00ec4c51 CM |
1557 | if (path->slots[0] == i) |
1558 | push_space += data_size + sizeof(*item); | |
db94535d CM |
1559 | |
1560 | if (!left->map_token) { | |
1561 | map_extent_buffer(left, (unsigned long)item, | |
1562 | sizeof(struct btrfs_item), | |
1563 | &left->map_token, &left->kaddr, | |
1564 | &left->map_start, &left->map_len, | |
1565 | KM_USER1); | |
1566 | } | |
1567 | ||
1568 | this_item_size = btrfs_item_size(left, item); | |
1569 | if (this_item_size + sizeof(*item) + push_space > free_space) | |
00ec4c51 CM |
1570 | break; |
1571 | push_items++; | |
db94535d | 1572 | push_space += this_item_size + sizeof(*item); |
34a38218 CM |
1573 | if (i == 0) |
1574 | break; | |
1575 | i--; | |
db94535d CM |
1576 | } |
1577 | if (left->map_token) { | |
1578 | unmap_extent_buffer(left, left->map_token, KM_USER1); | |
1579 | left->map_token = NULL; | |
00ec4c51 | 1580 | } |
5f39d397 | 1581 | |
00ec4c51 | 1582 | if (push_items == 0) { |
5f39d397 | 1583 | free_extent_buffer(right); |
00ec4c51 CM |
1584 | return 1; |
1585 | } | |
5f39d397 | 1586 | |
34a38218 | 1587 | if (!empty && push_items == left_nritems) |
a429e513 | 1588 | WARN_ON(1); |
5f39d397 | 1589 | |
00ec4c51 | 1590 | /* push left to right */ |
5f39d397 | 1591 | right_nritems = btrfs_header_nritems(right); |
34a38218 | 1592 | |
5f39d397 | 1593 | push_space = btrfs_item_end_nr(left, left_nritems - push_items); |
123abc88 | 1594 | push_space -= leaf_data_end(root, left); |
5f39d397 | 1595 | |
00ec4c51 | 1596 | /* make room in the right data area */ |
5f39d397 CM |
1597 | data_end = leaf_data_end(root, right); |
1598 | memmove_extent_buffer(right, | |
1599 | btrfs_leaf_data(right) + data_end - push_space, | |
1600 | btrfs_leaf_data(right) + data_end, | |
1601 | BTRFS_LEAF_DATA_SIZE(root) - data_end); | |
1602 | ||
00ec4c51 | 1603 | /* copy from the left data area */ |
5f39d397 | 1604 | copy_extent_buffer(right, left, btrfs_leaf_data(right) + |
d6025579 CM |
1605 | BTRFS_LEAF_DATA_SIZE(root) - push_space, |
1606 | btrfs_leaf_data(left) + leaf_data_end(root, left), | |
1607 | push_space); | |
5f39d397 CM |
1608 | |
1609 | memmove_extent_buffer(right, btrfs_item_nr_offset(push_items), | |
1610 | btrfs_item_nr_offset(0), | |
1611 | right_nritems * sizeof(struct btrfs_item)); | |
1612 | ||
00ec4c51 | 1613 | /* copy the items from left to right */ |
5f39d397 CM |
1614 | copy_extent_buffer(right, left, btrfs_item_nr_offset(0), |
1615 | btrfs_item_nr_offset(left_nritems - push_items), | |
1616 | push_items * sizeof(struct btrfs_item)); | |
00ec4c51 CM |
1617 | |
1618 | /* update the item pointers */ | |
7518a238 | 1619 | right_nritems += push_items; |
5f39d397 | 1620 | btrfs_set_header_nritems(right, right_nritems); |
123abc88 | 1621 | push_space = BTRFS_LEAF_DATA_SIZE(root); |
7518a238 | 1622 | for (i = 0; i < right_nritems; i++) { |
5f39d397 | 1623 | item = btrfs_item_nr(right, i); |
db94535d CM |
1624 | if (!right->map_token) { |
1625 | map_extent_buffer(right, (unsigned long)item, | |
1626 | sizeof(struct btrfs_item), | |
1627 | &right->map_token, &right->kaddr, | |
1628 | &right->map_start, &right->map_len, | |
1629 | KM_USER1); | |
1630 | } | |
1631 | push_space -= btrfs_item_size(right, item); | |
1632 | btrfs_set_item_offset(right, item, push_space); | |
1633 | } | |
1634 | ||
1635 | if (right->map_token) { | |
1636 | unmap_extent_buffer(right, right->map_token, KM_USER1); | |
1637 | right->map_token = NULL; | |
00ec4c51 | 1638 | } |
7518a238 | 1639 | left_nritems -= push_items; |
5f39d397 | 1640 | btrfs_set_header_nritems(left, left_nritems); |
00ec4c51 | 1641 | |
34a38218 CM |
1642 | if (left_nritems) |
1643 | btrfs_mark_buffer_dirty(left); | |
5f39d397 | 1644 | btrfs_mark_buffer_dirty(right); |
a429e513 | 1645 | |
5f39d397 CM |
1646 | btrfs_item_key(right, &disk_key, 0); |
1647 | btrfs_set_node_key(upper, &disk_key, slot + 1); | |
d6025579 | 1648 | btrfs_mark_buffer_dirty(upper); |
02217ed2 | 1649 | |
00ec4c51 | 1650 | /* then fixup the leaf pointer in the path */ |
7518a238 CM |
1651 | if (path->slots[0] >= left_nritems) { |
1652 | path->slots[0] -= left_nritems; | |
5f39d397 CM |
1653 | free_extent_buffer(path->nodes[0]); |
1654 | path->nodes[0] = right; | |
00ec4c51 CM |
1655 | path->slots[1] += 1; |
1656 | } else { | |
5f39d397 | 1657 | free_extent_buffer(right); |
00ec4c51 CM |
1658 | } |
1659 | return 0; | |
1660 | } | |
74123bd7 CM |
1661 | /* |
1662 | * push some data in the path leaf to the left, trying to free up at | |
1663 | * least data_size bytes. returns zero if the push worked, nonzero otherwise | |
1664 | */ | |
e089f05c | 1665 | static int push_leaf_left(struct btrfs_trans_handle *trans, struct btrfs_root |
34a38218 CM |
1666 | *root, struct btrfs_path *path, int data_size, |
1667 | int empty) | |
be0e5c09 | 1668 | { |
5f39d397 CM |
1669 | struct btrfs_disk_key disk_key; |
1670 | struct extent_buffer *right = path->nodes[0]; | |
1671 | struct extent_buffer *left; | |
be0e5c09 CM |
1672 | int slot; |
1673 | int i; | |
1674 | int free_space; | |
1675 | int push_space = 0; | |
1676 | int push_items = 0; | |
0783fcfc | 1677 | struct btrfs_item *item; |
7518a238 | 1678 | u32 old_left_nritems; |
5f39d397 | 1679 | u32 right_nritems; |
34a38218 | 1680 | u32 nr; |
aa5d6bed CM |
1681 | int ret = 0; |
1682 | int wret; | |
db94535d CM |
1683 | u32 this_item_size; |
1684 | u32 old_left_item_size; | |
be0e5c09 CM |
1685 | |
1686 | slot = path->slots[1]; | |
5f39d397 | 1687 | if (slot == 0) |
be0e5c09 | 1688 | return 1; |
5f39d397 | 1689 | if (!path->nodes[1]) |
be0e5c09 | 1690 | return 1; |
5f39d397 | 1691 | |
3685f791 CM |
1692 | right_nritems = btrfs_header_nritems(right); |
1693 | if (right_nritems == 0) { | |
1694 | return 1; | |
1695 | } | |
1696 | ||
5f39d397 | 1697 | left = read_tree_block(root, btrfs_node_blockptr(path->nodes[1], |
db94535d | 1698 | slot - 1), root->leafsize); |
123abc88 | 1699 | free_space = btrfs_leaf_free_space(root, left); |
0783fcfc | 1700 | if (free_space < data_size + sizeof(struct btrfs_item)) { |
5f39d397 | 1701 | free_extent_buffer(left); |
be0e5c09 CM |
1702 | return 1; |
1703 | } | |
02217ed2 CM |
1704 | |
1705 | /* cow and double check */ | |
5f39d397 CM |
1706 | ret = btrfs_cow_block(trans, root, left, |
1707 | path->nodes[1], slot - 1, &left); | |
54aa1f4d CM |
1708 | if (ret) { |
1709 | /* we hit -ENOSPC, but it isn't fatal here */ | |
5f39d397 | 1710 | free_extent_buffer(left); |
54aa1f4d CM |
1711 | return 1; |
1712 | } | |
3685f791 | 1713 | |
123abc88 | 1714 | free_space = btrfs_leaf_free_space(root, left); |
0783fcfc | 1715 | if (free_space < data_size + sizeof(struct btrfs_item)) { |
5f39d397 | 1716 | free_extent_buffer(left); |
02217ed2 CM |
1717 | return 1; |
1718 | } | |
1719 | ||
34a38218 CM |
1720 | if (empty) |
1721 | nr = right_nritems; | |
1722 | else | |
1723 | nr = right_nritems - 1; | |
1724 | ||
1725 | for (i = 0; i < nr; i++) { | |
5f39d397 | 1726 | item = btrfs_item_nr(right, i); |
db94535d CM |
1727 | if (!right->map_token) { |
1728 | map_extent_buffer(right, (unsigned long)item, | |
1729 | sizeof(struct btrfs_item), | |
1730 | &right->map_token, &right->kaddr, | |
1731 | &right->map_start, &right->map_len, | |
1732 | KM_USER1); | |
1733 | } | |
1734 | ||
be0e5c09 CM |
1735 | if (path->slots[0] == i) |
1736 | push_space += data_size + sizeof(*item); | |
db94535d CM |
1737 | |
1738 | this_item_size = btrfs_item_size(right, item); | |
1739 | if (this_item_size + sizeof(*item) + push_space > free_space) | |
be0e5c09 | 1740 | break; |
db94535d | 1741 | |
be0e5c09 | 1742 | push_items++; |
db94535d CM |
1743 | push_space += this_item_size + sizeof(*item); |
1744 | } | |
1745 | ||
1746 | if (right->map_token) { | |
1747 | unmap_extent_buffer(right, right->map_token, KM_USER1); | |
1748 | right->map_token = NULL; | |
be0e5c09 | 1749 | } |
db94535d | 1750 | |
be0e5c09 | 1751 | if (push_items == 0) { |
5f39d397 | 1752 | free_extent_buffer(left); |
be0e5c09 CM |
1753 | return 1; |
1754 | } | |
34a38218 | 1755 | if (!empty && push_items == btrfs_header_nritems(right)) |
a429e513 | 1756 | WARN_ON(1); |
5f39d397 | 1757 | |
be0e5c09 | 1758 | /* push data from right to left */ |
5f39d397 CM |
1759 | copy_extent_buffer(left, right, |
1760 | btrfs_item_nr_offset(btrfs_header_nritems(left)), | |
1761 | btrfs_item_nr_offset(0), | |
1762 | push_items * sizeof(struct btrfs_item)); | |
1763 | ||
123abc88 | 1764 | push_space = BTRFS_LEAF_DATA_SIZE(root) - |
5f39d397 CM |
1765 | btrfs_item_offset_nr(right, push_items -1); |
1766 | ||
1767 | copy_extent_buffer(left, right, btrfs_leaf_data(left) + | |
d6025579 CM |
1768 | leaf_data_end(root, left) - push_space, |
1769 | btrfs_leaf_data(right) + | |
5f39d397 | 1770 | btrfs_item_offset_nr(right, push_items - 1), |
d6025579 | 1771 | push_space); |
5f39d397 | 1772 | old_left_nritems = btrfs_header_nritems(left); |
eb60ceac CM |
1773 | BUG_ON(old_left_nritems < 0); |
1774 | ||
db94535d | 1775 | old_left_item_size = btrfs_item_offset_nr(left, old_left_nritems - 1); |
0783fcfc | 1776 | for (i = old_left_nritems; i < old_left_nritems + push_items; i++) { |
5f39d397 | 1777 | u32 ioff; |
db94535d | 1778 | |
5f39d397 | 1779 | item = btrfs_item_nr(left, i); |
db94535d CM |
1780 | if (!left->map_token) { |
1781 | map_extent_buffer(left, (unsigned long)item, | |
1782 | sizeof(struct btrfs_item), | |
1783 | &left->map_token, &left->kaddr, | |
1784 | &left->map_start, &left->map_len, | |
1785 | KM_USER1); | |
1786 | } | |
1787 | ||
5f39d397 CM |
1788 | ioff = btrfs_item_offset(left, item); |
1789 | btrfs_set_item_offset(left, item, | |
db94535d | 1790 | ioff - (BTRFS_LEAF_DATA_SIZE(root) - old_left_item_size)); |
be0e5c09 | 1791 | } |
5f39d397 | 1792 | btrfs_set_header_nritems(left, old_left_nritems + push_items); |
db94535d CM |
1793 | if (left->map_token) { |
1794 | unmap_extent_buffer(left, left->map_token, KM_USER1); | |
1795 | left->map_token = NULL; | |
1796 | } | |
be0e5c09 CM |
1797 | |
1798 | /* fixup right node */ | |
34a38218 CM |
1799 | if (push_items > right_nritems) { |
1800 | printk("push items %d nr %u\n", push_items, right_nritems); | |
1801 | WARN_ON(1); | |
1802 | } | |
1803 | ||
1804 | if (push_items < right_nritems) { | |
1805 | push_space = btrfs_item_offset_nr(right, push_items - 1) - | |
1806 | leaf_data_end(root, right); | |
1807 | memmove_extent_buffer(right, btrfs_leaf_data(right) + | |
1808 | BTRFS_LEAF_DATA_SIZE(root) - push_space, | |
1809 | btrfs_leaf_data(right) + | |
1810 | leaf_data_end(root, right), push_space); | |
1811 | ||
1812 | memmove_extent_buffer(right, btrfs_item_nr_offset(0), | |
5f39d397 CM |
1813 | btrfs_item_nr_offset(push_items), |
1814 | (btrfs_header_nritems(right) - push_items) * | |
1815 | sizeof(struct btrfs_item)); | |
34a38218 | 1816 | } |
eef1c494 Y |
1817 | right_nritems -= push_items; |
1818 | btrfs_set_header_nritems(right, right_nritems); | |
123abc88 | 1819 | push_space = BTRFS_LEAF_DATA_SIZE(root); |
5f39d397 CM |
1820 | for (i = 0; i < right_nritems; i++) { |
1821 | item = btrfs_item_nr(right, i); | |
db94535d CM |
1822 | |
1823 | if (!right->map_token) { | |
1824 | map_extent_buffer(right, (unsigned long)item, | |
1825 | sizeof(struct btrfs_item), | |
1826 | &right->map_token, &right->kaddr, | |
1827 | &right->map_start, &right->map_len, | |
1828 | KM_USER1); | |
1829 | } | |
1830 | ||
1831 | push_space = push_space - btrfs_item_size(right, item); | |
1832 | btrfs_set_item_offset(right, item, push_space); | |
1833 | } | |
1834 | if (right->map_token) { | |
1835 | unmap_extent_buffer(right, right->map_token, KM_USER1); | |
1836 | right->map_token = NULL; | |
be0e5c09 | 1837 | } |
eb60ceac | 1838 | |
5f39d397 | 1839 | btrfs_mark_buffer_dirty(left); |
34a38218 CM |
1840 | if (right_nritems) |
1841 | btrfs_mark_buffer_dirty(right); | |
098f59c2 | 1842 | |
5f39d397 CM |
1843 | btrfs_item_key(right, &disk_key, 0); |
1844 | wret = fixup_low_keys(trans, root, path, &disk_key, 1); | |
aa5d6bed CM |
1845 | if (wret) |
1846 | ret = wret; | |
be0e5c09 CM |
1847 | |
1848 | /* then fixup the leaf pointer in the path */ | |
1849 | if (path->slots[0] < push_items) { | |
1850 | path->slots[0] += old_left_nritems; | |
5f39d397 CM |
1851 | free_extent_buffer(path->nodes[0]); |
1852 | path->nodes[0] = left; | |
be0e5c09 CM |
1853 | path->slots[1] -= 1; |
1854 | } else { | |
5f39d397 | 1855 | free_extent_buffer(left); |
be0e5c09 CM |
1856 | path->slots[0] -= push_items; |
1857 | } | |
eb60ceac | 1858 | BUG_ON(path->slots[0] < 0); |
aa5d6bed | 1859 | return ret; |
be0e5c09 CM |
1860 | } |
1861 | ||
74123bd7 CM |
1862 | /* |
1863 | * split the path's leaf in two, making sure there is at least data_size | |
1864 | * available for the resulting leaf level of the path. | |
aa5d6bed CM |
1865 | * |
1866 | * returns 0 if all went well and < 0 on failure. | |
74123bd7 | 1867 | */ |
e089f05c | 1868 | static int split_leaf(struct btrfs_trans_handle *trans, struct btrfs_root |
d4dbff95 | 1869 | *root, struct btrfs_key *ins_key, |
cc0c5538 | 1870 | struct btrfs_path *path, int data_size, int extend) |
be0e5c09 | 1871 | { |
7bb86316 | 1872 | u64 root_gen; |
5f39d397 | 1873 | struct extent_buffer *l; |
7518a238 | 1874 | u32 nritems; |
eb60ceac CM |
1875 | int mid; |
1876 | int slot; | |
5f39d397 | 1877 | struct extent_buffer *right; |
0783fcfc | 1878 | int space_needed = data_size + sizeof(struct btrfs_item); |
be0e5c09 CM |
1879 | int data_copy_size; |
1880 | int rt_data_off; | |
1881 | int i; | |
d4dbff95 | 1882 | int ret = 0; |
aa5d6bed | 1883 | int wret; |
cc0c5538 CM |
1884 | int double_split; |
1885 | int num_doubles = 0; | |
d4dbff95 | 1886 | struct btrfs_disk_key disk_key; |
aa5d6bed | 1887 | |
cc0c5538 CM |
1888 | if (extend) |
1889 | space_needed = data_size; | |
1890 | ||
7bb86316 CM |
1891 | if (root->ref_cows) |
1892 | root_gen = trans->transid; | |
1893 | else | |
1894 | root_gen = 0; | |
1895 | ||
40689478 | 1896 | /* first try to make some room by pushing left and right */ |
3685f791 | 1897 | if (ins_key->type != BTRFS_DIR_ITEM_KEY) { |
34a38218 | 1898 | wret = push_leaf_right(trans, root, path, data_size, 0); |
3685f791 | 1899 | if (wret < 0) { |
eaee50e8 | 1900 | return wret; |
3685f791 CM |
1901 | } |
1902 | if (wret) { | |
34a38218 | 1903 | wret = push_leaf_left(trans, root, path, data_size, 0); |
3685f791 CM |
1904 | if (wret < 0) |
1905 | return wret; | |
1906 | } | |
1907 | l = path->nodes[0]; | |
aa5d6bed | 1908 | |
3685f791 | 1909 | /* did the pushes work? */ |
cc0c5538 | 1910 | if (btrfs_leaf_free_space(root, l) >= space_needed) |
3685f791 | 1911 | return 0; |
3326d1b0 | 1912 | } |
aa5d6bed | 1913 | |
5c680ed6 | 1914 | if (!path->nodes[1]) { |
e089f05c | 1915 | ret = insert_new_root(trans, root, path, 1); |
5c680ed6 CM |
1916 | if (ret) |
1917 | return ret; | |
1918 | } | |
cc0c5538 CM |
1919 | again: |
1920 | double_split = 0; | |
1921 | l = path->nodes[0]; | |
eb60ceac | 1922 | slot = path->slots[0]; |
5f39d397 | 1923 | nritems = btrfs_header_nritems(l); |
eb60ceac | 1924 | mid = (nritems + 1)/ 2; |
54aa1f4d | 1925 | |
7bb86316 CM |
1926 | btrfs_item_key(l, &disk_key, 0); |
1927 | ||
1928 | right = __btrfs_alloc_free_block(trans, root, root->leafsize, | |
1929 | root->root_key.objectid, | |
1930 | root_gen, disk_key.objectid, 0, | |
1931 | l->start, 0); | |
5f39d397 CM |
1932 | if (IS_ERR(right)) |
1933 | return PTR_ERR(right); | |
1934 | ||
1935 | memset_extent_buffer(right, 0, 0, sizeof(struct btrfs_header)); | |
db94535d | 1936 | btrfs_set_header_bytenr(right, right->start); |
5f39d397 CM |
1937 | btrfs_set_header_generation(right, trans->transid); |
1938 | btrfs_set_header_owner(right, root->root_key.objectid); | |
1939 | btrfs_set_header_level(right, 0); | |
1940 | write_extent_buffer(right, root->fs_info->fsid, | |
1941 | (unsigned long)btrfs_header_fsid(right), | |
1942 | BTRFS_FSID_SIZE); | |
d4dbff95 CM |
1943 | if (mid <= slot) { |
1944 | if (nritems == 1 || | |
1945 | leaf_space_used(l, mid, nritems - mid) + space_needed > | |
1946 | BTRFS_LEAF_DATA_SIZE(root)) { | |
1947 | if (slot >= nritems) { | |
1948 | btrfs_cpu_key_to_disk(&disk_key, ins_key); | |
5f39d397 | 1949 | btrfs_set_header_nritems(right, 0); |
d4dbff95 | 1950 | wret = insert_ptr(trans, root, path, |
db94535d | 1951 | &disk_key, right->start, |
d4dbff95 CM |
1952 | path->slots[1] + 1, 1); |
1953 | if (wret) | |
1954 | ret = wret; | |
5f39d397 CM |
1955 | free_extent_buffer(path->nodes[0]); |
1956 | path->nodes[0] = right; | |
d4dbff95 CM |
1957 | path->slots[0] = 0; |
1958 | path->slots[1] += 1; | |
1959 | return ret; | |
1960 | } | |
1961 | mid = slot; | |
3326d1b0 CM |
1962 | if (mid != nritems && |
1963 | leaf_space_used(l, mid, nritems - mid) + | |
1964 | space_needed > BTRFS_LEAF_DATA_SIZE(root)) { | |
1965 | double_split = 1; | |
1966 | } | |
d4dbff95 CM |
1967 | } |
1968 | } else { | |
1969 | if (leaf_space_used(l, 0, mid + 1) + space_needed > | |
1970 | BTRFS_LEAF_DATA_SIZE(root)) { | |
cc0c5538 | 1971 | if (!extend && slot == 0) { |
d4dbff95 | 1972 | btrfs_cpu_key_to_disk(&disk_key, ins_key); |
5f39d397 | 1973 | btrfs_set_header_nritems(right, 0); |
d4dbff95 CM |
1974 | wret = insert_ptr(trans, root, path, |
1975 | &disk_key, | |
db94535d | 1976 | right->start, |
098f59c2 | 1977 | path->slots[1], 1); |
d4dbff95 CM |
1978 | if (wret) |
1979 | ret = wret; | |
5f39d397 CM |
1980 | free_extent_buffer(path->nodes[0]); |
1981 | path->nodes[0] = right; | |
d4dbff95 | 1982 | path->slots[0] = 0; |
a429e513 CM |
1983 | if (path->slots[1] == 0) { |
1984 | wret = fixup_low_keys(trans, root, | |
1985 | path, &disk_key, 1); | |
1986 | if (wret) | |
1987 | ret = wret; | |
1988 | } | |
d4dbff95 | 1989 | return ret; |
cc0c5538 CM |
1990 | } else if (extend && slot == 0) { |
1991 | mid = 1; | |
1992 | } else { | |
1993 | mid = slot; | |
1994 | if (mid != nritems && | |
1995 | leaf_space_used(l, mid, nritems - mid) + | |
1996 | space_needed > BTRFS_LEAF_DATA_SIZE(root)) { | |
1997 | double_split = 1; | |
1998 | } | |
5ee78ac7 | 1999 | } |
d4dbff95 CM |
2000 | } |
2001 | } | |
5f39d397 CM |
2002 | nritems = nritems - mid; |
2003 | btrfs_set_header_nritems(right, nritems); | |
2004 | data_copy_size = btrfs_item_end_nr(l, mid) - leaf_data_end(root, l); | |
2005 | ||
2006 | copy_extent_buffer(right, l, btrfs_item_nr_offset(0), | |
2007 | btrfs_item_nr_offset(mid), | |
2008 | nritems * sizeof(struct btrfs_item)); | |
2009 | ||
2010 | copy_extent_buffer(right, l, | |
d6025579 CM |
2011 | btrfs_leaf_data(right) + BTRFS_LEAF_DATA_SIZE(root) - |
2012 | data_copy_size, btrfs_leaf_data(l) + | |
2013 | leaf_data_end(root, l), data_copy_size); | |
5f39d397 | 2014 | |
123abc88 | 2015 | rt_data_off = BTRFS_LEAF_DATA_SIZE(root) - |
5f39d397 | 2016 | btrfs_item_end_nr(l, mid); |
74123bd7 | 2017 | |
5f39d397 CM |
2018 | for (i = 0; i < nritems; i++) { |
2019 | struct btrfs_item *item = btrfs_item_nr(right, i); | |
db94535d CM |
2020 | u32 ioff; |
2021 | ||
2022 | if (!right->map_token) { | |
2023 | map_extent_buffer(right, (unsigned long)item, | |
2024 | sizeof(struct btrfs_item), | |
2025 | &right->map_token, &right->kaddr, | |
2026 | &right->map_start, &right->map_len, | |
2027 | KM_USER1); | |
2028 | } | |
2029 | ||
2030 | ioff = btrfs_item_offset(right, item); | |
5f39d397 | 2031 | btrfs_set_item_offset(right, item, ioff + rt_data_off); |
0783fcfc | 2032 | } |
74123bd7 | 2033 | |
db94535d CM |
2034 | if (right->map_token) { |
2035 | unmap_extent_buffer(right, right->map_token, KM_USER1); | |
2036 | right->map_token = NULL; | |
2037 | } | |
2038 | ||
5f39d397 | 2039 | btrfs_set_header_nritems(l, mid); |
aa5d6bed | 2040 | ret = 0; |
5f39d397 | 2041 | btrfs_item_key(right, &disk_key, 0); |
db94535d CM |
2042 | wret = insert_ptr(trans, root, path, &disk_key, right->start, |
2043 | path->slots[1] + 1, 1); | |
aa5d6bed CM |
2044 | if (wret) |
2045 | ret = wret; | |
5f39d397 CM |
2046 | |
2047 | btrfs_mark_buffer_dirty(right); | |
2048 | btrfs_mark_buffer_dirty(l); | |
eb60ceac | 2049 | BUG_ON(path->slots[0] != slot); |
5f39d397 | 2050 | |
be0e5c09 | 2051 | if (mid <= slot) { |
5f39d397 CM |
2052 | free_extent_buffer(path->nodes[0]); |
2053 | path->nodes[0] = right; | |
be0e5c09 CM |
2054 | path->slots[0] -= mid; |
2055 | path->slots[1] += 1; | |
eb60ceac | 2056 | } else |
5f39d397 CM |
2057 | free_extent_buffer(right); |
2058 | ||
eb60ceac | 2059 | BUG_ON(path->slots[0] < 0); |
d4dbff95 | 2060 | |
cc0c5538 CM |
2061 | if (double_split) { |
2062 | BUG_ON(num_doubles != 0); | |
2063 | num_doubles++; | |
2064 | goto again; | |
a429e513 | 2065 | } |
be0e5c09 CM |
2066 | return ret; |
2067 | } | |
2068 | ||
b18c6685 CM |
2069 | int btrfs_truncate_item(struct btrfs_trans_handle *trans, |
2070 | struct btrfs_root *root, | |
2071 | struct btrfs_path *path, | |
179e29e4 | 2072 | u32 new_size, int from_end) |
b18c6685 CM |
2073 | { |
2074 | int ret = 0; | |
2075 | int slot; | |
2076 | int slot_orig; | |
5f39d397 CM |
2077 | struct extent_buffer *leaf; |
2078 | struct btrfs_item *item; | |
b18c6685 CM |
2079 | u32 nritems; |
2080 | unsigned int data_end; | |
2081 | unsigned int old_data_start; | |
2082 | unsigned int old_size; | |
2083 | unsigned int size_diff; | |
2084 | int i; | |
2085 | ||
2086 | slot_orig = path->slots[0]; | |
5f39d397 | 2087 | leaf = path->nodes[0]; |
179e29e4 CM |
2088 | slot = path->slots[0]; |
2089 | ||
2090 | old_size = btrfs_item_size_nr(leaf, slot); | |
2091 | if (old_size == new_size) | |
2092 | return 0; | |
b18c6685 | 2093 | |
5f39d397 | 2094 | nritems = btrfs_header_nritems(leaf); |
b18c6685 CM |
2095 | data_end = leaf_data_end(root, leaf); |
2096 | ||
5f39d397 | 2097 | old_data_start = btrfs_item_offset_nr(leaf, slot); |
179e29e4 | 2098 | |
b18c6685 CM |
2099 | size_diff = old_size - new_size; |
2100 | ||
2101 | BUG_ON(slot < 0); | |
2102 | BUG_ON(slot >= nritems); | |
2103 | ||
2104 | /* | |
2105 | * item0..itemN ... dataN.offset..dataN.size .. data0.size | |
2106 | */ | |
2107 | /* first correct the data pointers */ | |
2108 | for (i = slot; i < nritems; i++) { | |
5f39d397 CM |
2109 | u32 ioff; |
2110 | item = btrfs_item_nr(leaf, i); | |
db94535d CM |
2111 | |
2112 | if (!leaf->map_token) { | |
2113 | map_extent_buffer(leaf, (unsigned long)item, | |
2114 | sizeof(struct btrfs_item), | |
2115 | &leaf->map_token, &leaf->kaddr, | |
2116 | &leaf->map_start, &leaf->map_len, | |
2117 | KM_USER1); | |
2118 | } | |
2119 | ||
5f39d397 CM |
2120 | ioff = btrfs_item_offset(leaf, item); |
2121 | btrfs_set_item_offset(leaf, item, ioff + size_diff); | |
b18c6685 | 2122 | } |
db94535d CM |
2123 | |
2124 | if (leaf->map_token) { | |
2125 | unmap_extent_buffer(leaf, leaf->map_token, KM_USER1); | |
2126 | leaf->map_token = NULL; | |
2127 | } | |
2128 | ||
b18c6685 | 2129 | /* shift the data */ |
179e29e4 CM |
2130 | if (from_end) { |
2131 | memmove_extent_buffer(leaf, btrfs_leaf_data(leaf) + | |
2132 | data_end + size_diff, btrfs_leaf_data(leaf) + | |
2133 | data_end, old_data_start + new_size - data_end); | |
2134 | } else { | |
2135 | struct btrfs_disk_key disk_key; | |
2136 | u64 offset; | |
2137 | ||
2138 | btrfs_item_key(leaf, &disk_key, slot); | |
2139 | ||
2140 | if (btrfs_disk_key_type(&disk_key) == BTRFS_EXTENT_DATA_KEY) { | |
2141 | unsigned long ptr; | |
2142 | struct btrfs_file_extent_item *fi; | |
2143 | ||
2144 | fi = btrfs_item_ptr(leaf, slot, | |
2145 | struct btrfs_file_extent_item); | |
2146 | fi = (struct btrfs_file_extent_item *)( | |
2147 | (unsigned long)fi - size_diff); | |
2148 | ||
2149 | if (btrfs_file_extent_type(leaf, fi) == | |
2150 | BTRFS_FILE_EXTENT_INLINE) { | |
2151 | ptr = btrfs_item_ptr_offset(leaf, slot); | |
2152 | memmove_extent_buffer(leaf, ptr, | |
2153 | (unsigned long)fi, | |
2154 | offsetof(struct btrfs_file_extent_item, | |
2155 | disk_bytenr)); | |
2156 | } | |
2157 | } | |
2158 | ||
2159 | memmove_extent_buffer(leaf, btrfs_leaf_data(leaf) + | |
2160 | data_end + size_diff, btrfs_leaf_data(leaf) + | |
2161 | data_end, old_data_start - data_end); | |
2162 | ||
2163 | offset = btrfs_disk_key_offset(&disk_key); | |
2164 | btrfs_set_disk_key_offset(&disk_key, offset + size_diff); | |
2165 | btrfs_set_item_key(leaf, &disk_key, slot); | |
2166 | if (slot == 0) | |
2167 | fixup_low_keys(trans, root, path, &disk_key, 1); | |
2168 | } | |
5f39d397 CM |
2169 | |
2170 | item = btrfs_item_nr(leaf, slot); | |
2171 | btrfs_set_item_size(leaf, item, new_size); | |
2172 | btrfs_mark_buffer_dirty(leaf); | |
b18c6685 CM |
2173 | |
2174 | ret = 0; | |
5f39d397 CM |
2175 | if (btrfs_leaf_free_space(root, leaf) < 0) { |
2176 | btrfs_print_leaf(root, leaf); | |
b18c6685 | 2177 | BUG(); |
5f39d397 | 2178 | } |
b18c6685 CM |
2179 | return ret; |
2180 | } | |
2181 | ||
5f39d397 CM |
2182 | int btrfs_extend_item(struct btrfs_trans_handle *trans, |
2183 | struct btrfs_root *root, struct btrfs_path *path, | |
2184 | u32 data_size) | |
6567e837 CM |
2185 | { |
2186 | int ret = 0; | |
2187 | int slot; | |
2188 | int slot_orig; | |
5f39d397 CM |
2189 | struct extent_buffer *leaf; |
2190 | struct btrfs_item *item; | |
6567e837 CM |
2191 | u32 nritems; |
2192 | unsigned int data_end; | |
2193 | unsigned int old_data; | |
2194 | unsigned int old_size; | |
2195 | int i; | |
2196 | ||
2197 | slot_orig = path->slots[0]; | |
5f39d397 | 2198 | leaf = path->nodes[0]; |
6567e837 | 2199 | |
5f39d397 | 2200 | nritems = btrfs_header_nritems(leaf); |
6567e837 CM |
2201 | data_end = leaf_data_end(root, leaf); |
2202 | ||
5f39d397 CM |
2203 | if (btrfs_leaf_free_space(root, leaf) < data_size) { |
2204 | btrfs_print_leaf(root, leaf); | |
6567e837 | 2205 | BUG(); |
5f39d397 | 2206 | } |
6567e837 | 2207 | slot = path->slots[0]; |
5f39d397 | 2208 | old_data = btrfs_item_end_nr(leaf, slot); |
6567e837 CM |
2209 | |
2210 | BUG_ON(slot < 0); | |
3326d1b0 CM |
2211 | if (slot >= nritems) { |
2212 | btrfs_print_leaf(root, leaf); | |
2213 | printk("slot %d too large, nritems %d\n", slot, nritems); | |
2214 | BUG_ON(1); | |
2215 | } | |
6567e837 CM |
2216 | |
2217 | /* | |
2218 | * item0..itemN ... dataN.offset..dataN.size .. data0.size | |
2219 | */ | |
2220 | /* first correct the data pointers */ | |
2221 | for (i = slot; i < nritems; i++) { | |
5f39d397 CM |
2222 | u32 ioff; |
2223 | item = btrfs_item_nr(leaf, i); | |
db94535d CM |
2224 | |
2225 | if (!leaf->map_token) { | |
2226 | map_extent_buffer(leaf, (unsigned long)item, | |
2227 | sizeof(struct btrfs_item), | |
2228 | &leaf->map_token, &leaf->kaddr, | |
2229 | &leaf->map_start, &leaf->map_len, | |
2230 | KM_USER1); | |
2231 | } | |
5f39d397 CM |
2232 | ioff = btrfs_item_offset(leaf, item); |
2233 | btrfs_set_item_offset(leaf, item, ioff - data_size); | |
6567e837 | 2234 | } |
5f39d397 | 2235 | |
db94535d CM |
2236 | if (leaf->map_token) { |
2237 | unmap_extent_buffer(leaf, leaf->map_token, KM_USER1); | |
2238 | leaf->map_token = NULL; | |
2239 | } | |
2240 | ||
6567e837 | 2241 | /* shift the data */ |
5f39d397 | 2242 | memmove_extent_buffer(leaf, btrfs_leaf_data(leaf) + |
6567e837 CM |
2243 | data_end - data_size, btrfs_leaf_data(leaf) + |
2244 | data_end, old_data - data_end); | |
5f39d397 | 2245 | |
6567e837 | 2246 | data_end = old_data; |
5f39d397 CM |
2247 | old_size = btrfs_item_size_nr(leaf, slot); |
2248 | item = btrfs_item_nr(leaf, slot); | |
2249 | btrfs_set_item_size(leaf, item, old_size + data_size); | |
2250 | btrfs_mark_buffer_dirty(leaf); | |
6567e837 CM |
2251 | |
2252 | ret = 0; | |
5f39d397 CM |
2253 | if (btrfs_leaf_free_space(root, leaf) < 0) { |
2254 | btrfs_print_leaf(root, leaf); | |
6567e837 | 2255 | BUG(); |
5f39d397 | 2256 | } |
6567e837 CM |
2257 | return ret; |
2258 | } | |
2259 | ||
74123bd7 CM |
2260 | /* |
2261 | * Given a key and some data, insert an item into the tree. | |
2262 | * This does all the path init required, making room in the tree if needed. | |
2263 | */ | |
5f39d397 CM |
2264 | int btrfs_insert_empty_item(struct btrfs_trans_handle *trans, |
2265 | struct btrfs_root *root, | |
2266 | struct btrfs_path *path, | |
2267 | struct btrfs_key *cpu_key, u32 data_size) | |
be0e5c09 | 2268 | { |
5f39d397 CM |
2269 | struct extent_buffer *leaf; |
2270 | struct btrfs_item *item; | |
aa5d6bed | 2271 | int ret = 0; |
be0e5c09 | 2272 | int slot; |
eb60ceac | 2273 | int slot_orig; |
7518a238 | 2274 | u32 nritems; |
be0e5c09 | 2275 | unsigned int data_end; |
e2fa7227 CM |
2276 | struct btrfs_disk_key disk_key; |
2277 | ||
2278 | btrfs_cpu_key_to_disk(&disk_key, cpu_key); | |
be0e5c09 | 2279 | |
74123bd7 | 2280 | /* create a root if there isn't one */ |
5c680ed6 | 2281 | if (!root->node) |
cfaa7295 | 2282 | BUG(); |
5f39d397 | 2283 | |
e089f05c | 2284 | ret = btrfs_search_slot(trans, root, cpu_key, path, data_size, 1); |
eb60ceac | 2285 | if (ret == 0) { |
f0930a37 | 2286 | return -EEXIST; |
aa5d6bed | 2287 | } |
ed2ff2cb CM |
2288 | if (ret < 0) |
2289 | goto out; | |
be0e5c09 | 2290 | |
62e2749e | 2291 | slot_orig = path->slots[0]; |
5f39d397 | 2292 | leaf = path->nodes[0]; |
74123bd7 | 2293 | |
5f39d397 | 2294 | nritems = btrfs_header_nritems(leaf); |
123abc88 | 2295 | data_end = leaf_data_end(root, leaf); |
eb60ceac | 2296 | |
123abc88 | 2297 | if (btrfs_leaf_free_space(root, leaf) < |
d4dbff95 | 2298 | sizeof(struct btrfs_item) + data_size) { |
3326d1b0 CM |
2299 | btrfs_print_leaf(root, leaf); |
2300 | printk("not enough freespace need %u have %d\n", | |
2301 | data_size, btrfs_leaf_free_space(root, leaf)); | |
be0e5c09 | 2302 | BUG(); |
d4dbff95 | 2303 | } |
5f39d397 | 2304 | |
62e2749e | 2305 | slot = path->slots[0]; |
eb60ceac | 2306 | BUG_ON(slot < 0); |
5f39d397 | 2307 | |
be0e5c09 CM |
2308 | if (slot != nritems) { |
2309 | int i; | |
5f39d397 | 2310 | unsigned int old_data = btrfs_item_end_nr(leaf, slot); |
be0e5c09 | 2311 | |
5f39d397 CM |
2312 | if (old_data < data_end) { |
2313 | btrfs_print_leaf(root, leaf); | |
2314 | printk("slot %d old_data %d data_end %d\n", | |
2315 | slot, old_data, data_end); | |
2316 | BUG_ON(1); | |
2317 | } | |
be0e5c09 CM |
2318 | /* |
2319 | * item0..itemN ... dataN.offset..dataN.size .. data0.size | |
2320 | */ | |
2321 | /* first correct the data pointers */ | |
db94535d | 2322 | WARN_ON(leaf->map_token); |
0783fcfc | 2323 | for (i = slot; i < nritems; i++) { |
5f39d397 | 2324 | u32 ioff; |
db94535d | 2325 | |
5f39d397 | 2326 | item = btrfs_item_nr(leaf, i); |
db94535d CM |
2327 | if (!leaf->map_token) { |
2328 | map_extent_buffer(leaf, (unsigned long)item, | |
2329 | sizeof(struct btrfs_item), | |
2330 | &leaf->map_token, &leaf->kaddr, | |
2331 | &leaf->map_start, &leaf->map_len, | |
2332 | KM_USER1); | |
2333 | } | |
2334 | ||
5f39d397 CM |
2335 | ioff = btrfs_item_offset(leaf, item); |
2336 | btrfs_set_item_offset(leaf, item, ioff - data_size); | |
0783fcfc | 2337 | } |
db94535d CM |
2338 | if (leaf->map_token) { |
2339 | unmap_extent_buffer(leaf, leaf->map_token, KM_USER1); | |
2340 | leaf->map_token = NULL; | |
2341 | } | |
be0e5c09 CM |
2342 | |
2343 | /* shift the items */ | |
5f39d397 CM |
2344 | memmove_extent_buffer(leaf, btrfs_item_nr_offset(slot + 1), |
2345 | btrfs_item_nr_offset(slot), | |
d6025579 | 2346 | (nritems - slot) * sizeof(struct btrfs_item)); |
be0e5c09 CM |
2347 | |
2348 | /* shift the data */ | |
5f39d397 | 2349 | memmove_extent_buffer(leaf, btrfs_leaf_data(leaf) + |
d6025579 CM |
2350 | data_end - data_size, btrfs_leaf_data(leaf) + |
2351 | data_end, old_data - data_end); | |
be0e5c09 CM |
2352 | data_end = old_data; |
2353 | } | |
5f39d397 | 2354 | |
62e2749e | 2355 | /* setup the item for the new data */ |
5f39d397 CM |
2356 | btrfs_set_item_key(leaf, &disk_key, slot); |
2357 | item = btrfs_item_nr(leaf, slot); | |
2358 | btrfs_set_item_offset(leaf, item, data_end - data_size); | |
2359 | btrfs_set_item_size(leaf, item, data_size); | |
2360 | btrfs_set_header_nritems(leaf, nritems + 1); | |
2361 | btrfs_mark_buffer_dirty(leaf); | |
aa5d6bed CM |
2362 | |
2363 | ret = 0; | |
8e19f2cd | 2364 | if (slot == 0) |
e089f05c | 2365 | ret = fixup_low_keys(trans, root, path, &disk_key, 1); |
aa5d6bed | 2366 | |
5f39d397 CM |
2367 | if (btrfs_leaf_free_space(root, leaf) < 0) { |
2368 | btrfs_print_leaf(root, leaf); | |
be0e5c09 | 2369 | BUG(); |
5f39d397 | 2370 | } |
ed2ff2cb | 2371 | out: |
62e2749e CM |
2372 | return ret; |
2373 | } | |
2374 | ||
2375 | /* | |
2376 | * Given a key and some data, insert an item into the tree. | |
2377 | * This does all the path init required, making room in the tree if needed. | |
2378 | */ | |
e089f05c CM |
2379 | int btrfs_insert_item(struct btrfs_trans_handle *trans, struct btrfs_root |
2380 | *root, struct btrfs_key *cpu_key, void *data, u32 | |
2381 | data_size) | |
62e2749e CM |
2382 | { |
2383 | int ret = 0; | |
2c90e5d6 | 2384 | struct btrfs_path *path; |
5f39d397 CM |
2385 | struct extent_buffer *leaf; |
2386 | unsigned long ptr; | |
62e2749e | 2387 | |
2c90e5d6 CM |
2388 | path = btrfs_alloc_path(); |
2389 | BUG_ON(!path); | |
2c90e5d6 | 2390 | ret = btrfs_insert_empty_item(trans, root, path, cpu_key, data_size); |
62e2749e | 2391 | if (!ret) { |
5f39d397 CM |
2392 | leaf = path->nodes[0]; |
2393 | ptr = btrfs_item_ptr_offset(leaf, path->slots[0]); | |
2394 | write_extent_buffer(leaf, data, ptr, data_size); | |
2395 | btrfs_mark_buffer_dirty(leaf); | |
62e2749e | 2396 | } |
2c90e5d6 | 2397 | btrfs_free_path(path); |
aa5d6bed | 2398 | return ret; |
be0e5c09 CM |
2399 | } |
2400 | ||
74123bd7 | 2401 | /* |
5de08d7d | 2402 | * delete the pointer from a given node. |
74123bd7 CM |
2403 | * |
2404 | * If the delete empties a node, the node is removed from the tree, | |
2405 | * continuing all the way the root if required. The root is converted into | |
2406 | * a leaf if all the nodes are emptied. | |
2407 | */ | |
e089f05c CM |
2408 | static int del_ptr(struct btrfs_trans_handle *trans, struct btrfs_root *root, |
2409 | struct btrfs_path *path, int level, int slot) | |
be0e5c09 | 2410 | { |
5f39d397 | 2411 | struct extent_buffer *parent = path->nodes[level]; |
7518a238 | 2412 | u32 nritems; |
aa5d6bed | 2413 | int ret = 0; |
bb803951 | 2414 | int wret; |
be0e5c09 | 2415 | |
5f39d397 | 2416 | nritems = btrfs_header_nritems(parent); |
bb803951 | 2417 | if (slot != nritems -1) { |
5f39d397 CM |
2418 | memmove_extent_buffer(parent, |
2419 | btrfs_node_key_ptr_offset(slot), | |
2420 | btrfs_node_key_ptr_offset(slot + 1), | |
d6025579 CM |
2421 | sizeof(struct btrfs_key_ptr) * |
2422 | (nritems - slot - 1)); | |
bb803951 | 2423 | } |
7518a238 | 2424 | nritems--; |
5f39d397 | 2425 | btrfs_set_header_nritems(parent, nritems); |
7518a238 | 2426 | if (nritems == 0 && parent == root->node) { |
5f39d397 | 2427 | BUG_ON(btrfs_header_level(root->node) != 1); |
bb803951 | 2428 | /* just turn the root into a leaf and break */ |
5f39d397 | 2429 | btrfs_set_header_level(root->node, 0); |
bb803951 | 2430 | } else if (slot == 0) { |
5f39d397 CM |
2431 | struct btrfs_disk_key disk_key; |
2432 | ||
2433 | btrfs_node_key(parent, &disk_key, 0); | |
2434 | wret = fixup_low_keys(trans, root, path, &disk_key, level + 1); | |
0f70abe2 CM |
2435 | if (wret) |
2436 | ret = wret; | |
be0e5c09 | 2437 | } |
d6025579 | 2438 | btrfs_mark_buffer_dirty(parent); |
aa5d6bed | 2439 | return ret; |
be0e5c09 CM |
2440 | } |
2441 | ||
74123bd7 CM |
2442 | /* |
2443 | * delete the item at the leaf level in path. If that empties | |
2444 | * the leaf, remove it from the tree | |
2445 | */ | |
e089f05c CM |
2446 | int btrfs_del_item(struct btrfs_trans_handle *trans, struct btrfs_root *root, |
2447 | struct btrfs_path *path) | |
be0e5c09 | 2448 | { |
be0e5c09 | 2449 | int slot; |
5f39d397 CM |
2450 | struct extent_buffer *leaf; |
2451 | struct btrfs_item *item; | |
be0e5c09 CM |
2452 | int doff; |
2453 | int dsize; | |
aa5d6bed CM |
2454 | int ret = 0; |
2455 | int wret; | |
7518a238 | 2456 | u32 nritems; |
be0e5c09 | 2457 | |
5f39d397 | 2458 | leaf = path->nodes[0]; |
4920c9ac | 2459 | slot = path->slots[0]; |
5f39d397 CM |
2460 | doff = btrfs_item_offset_nr(leaf, slot); |
2461 | dsize = btrfs_item_size_nr(leaf, slot); | |
2462 | nritems = btrfs_header_nritems(leaf); | |
be0e5c09 | 2463 | |
7518a238 | 2464 | if (slot != nritems - 1) { |
be0e5c09 | 2465 | int i; |
123abc88 | 2466 | int data_end = leaf_data_end(root, leaf); |
5f39d397 CM |
2467 | |
2468 | memmove_extent_buffer(leaf, btrfs_leaf_data(leaf) + | |
d6025579 CM |
2469 | data_end + dsize, |
2470 | btrfs_leaf_data(leaf) + data_end, | |
2471 | doff - data_end); | |
5f39d397 | 2472 | |
0783fcfc | 2473 | for (i = slot + 1; i < nritems; i++) { |
5f39d397 | 2474 | u32 ioff; |
db94535d | 2475 | |
5f39d397 | 2476 | item = btrfs_item_nr(leaf, i); |
db94535d CM |
2477 | if (!leaf->map_token) { |
2478 | map_extent_buffer(leaf, (unsigned long)item, | |
2479 | sizeof(struct btrfs_item), | |
2480 | &leaf->map_token, &leaf->kaddr, | |
2481 | &leaf->map_start, &leaf->map_len, | |
2482 | KM_USER1); | |
2483 | } | |
5f39d397 CM |
2484 | ioff = btrfs_item_offset(leaf, item); |
2485 | btrfs_set_item_offset(leaf, item, ioff + dsize); | |
0783fcfc | 2486 | } |
db94535d CM |
2487 | |
2488 | if (leaf->map_token) { | |
2489 | unmap_extent_buffer(leaf, leaf->map_token, KM_USER1); | |
2490 | leaf->map_token = NULL; | |
2491 | } | |
2492 | ||
5f39d397 CM |
2493 | memmove_extent_buffer(leaf, btrfs_item_nr_offset(slot), |
2494 | btrfs_item_nr_offset(slot + 1), | |
d6025579 CM |
2495 | sizeof(struct btrfs_item) * |
2496 | (nritems - slot - 1)); | |
be0e5c09 | 2497 | } |
5f39d397 | 2498 | btrfs_set_header_nritems(leaf, nritems - 1); |
7518a238 | 2499 | nritems--; |
5f39d397 | 2500 | |
74123bd7 | 2501 | /* delete the leaf if we've emptied it */ |
7518a238 | 2502 | if (nritems == 0) { |
5f39d397 CM |
2503 | if (leaf == root->node) { |
2504 | btrfs_set_header_level(leaf, 0); | |
9a8dd150 | 2505 | } else { |
7bb86316 | 2506 | u64 root_gen = btrfs_header_generation(path->nodes[1]); |
5f39d397 CM |
2507 | clean_tree_block(trans, root, leaf); |
2508 | wait_on_tree_block_writeback(root, leaf); | |
e089f05c | 2509 | wret = del_ptr(trans, root, path, 1, path->slots[1]); |
aa5d6bed CM |
2510 | if (wret) |
2511 | ret = wret; | |
e089f05c | 2512 | wret = btrfs_free_extent(trans, root, |
7bb86316 CM |
2513 | leaf->start, leaf->len, |
2514 | btrfs_header_owner(path->nodes[1]), | |
2515 | root_gen, 0, 0, 1); | |
0f70abe2 CM |
2516 | if (wret) |
2517 | ret = wret; | |
9a8dd150 | 2518 | } |
be0e5c09 | 2519 | } else { |
7518a238 | 2520 | int used = leaf_space_used(leaf, 0, nritems); |
aa5d6bed | 2521 | if (slot == 0) { |
5f39d397 CM |
2522 | struct btrfs_disk_key disk_key; |
2523 | ||
2524 | btrfs_item_key(leaf, &disk_key, 0); | |
e089f05c | 2525 | wret = fixup_low_keys(trans, root, path, |
5f39d397 | 2526 | &disk_key, 1); |
aa5d6bed CM |
2527 | if (wret) |
2528 | ret = wret; | |
2529 | } | |
aa5d6bed | 2530 | |
74123bd7 | 2531 | /* delete the leaf if it is mostly empty */ |
7936ca38 | 2532 | if (used < BTRFS_LEAF_DATA_SIZE(root) / 3) { |
be0e5c09 CM |
2533 | /* push_leaf_left fixes the path. |
2534 | * make sure the path still points to our leaf | |
2535 | * for possible call to del_ptr below | |
2536 | */ | |
4920c9ac | 2537 | slot = path->slots[1]; |
5f39d397 CM |
2538 | extent_buffer_get(leaf); |
2539 | ||
34a38218 | 2540 | wret = push_leaf_right(trans, root, path, 1, 1); |
54aa1f4d | 2541 | if (wret < 0 && wret != -ENOSPC) |
aa5d6bed | 2542 | ret = wret; |
5f39d397 CM |
2543 | |
2544 | if (path->nodes[0] == leaf && | |
2545 | btrfs_header_nritems(leaf)) { | |
34a38218 | 2546 | wret = push_leaf_left(trans, root, path, 1, 1); |
54aa1f4d | 2547 | if (wret < 0 && wret != -ENOSPC) |
aa5d6bed CM |
2548 | ret = wret; |
2549 | } | |
5f39d397 CM |
2550 | |
2551 | if (btrfs_header_nritems(leaf) == 0) { | |
7bb86316 | 2552 | u64 root_gen; |
db94535d CM |
2553 | u64 bytenr = leaf->start; |
2554 | u32 blocksize = leaf->len; | |
5f39d397 | 2555 | |
7bb86316 CM |
2556 | root_gen = btrfs_header_generation( |
2557 | path->nodes[1]); | |
2558 | ||
5f39d397 CM |
2559 | clean_tree_block(trans, root, leaf); |
2560 | wait_on_tree_block_writeback(root, leaf); | |
2561 | ||
e089f05c | 2562 | wret = del_ptr(trans, root, path, 1, slot); |
aa5d6bed CM |
2563 | if (wret) |
2564 | ret = wret; | |
5f39d397 CM |
2565 | |
2566 | free_extent_buffer(leaf); | |
db94535d | 2567 | wret = btrfs_free_extent(trans, root, bytenr, |
7bb86316 CM |
2568 | blocksize, |
2569 | btrfs_header_owner(path->nodes[1]), | |
2570 | root_gen, 0, 0, 1); | |
0f70abe2 CM |
2571 | if (wret) |
2572 | ret = wret; | |
5de08d7d | 2573 | } else { |
5f39d397 CM |
2574 | btrfs_mark_buffer_dirty(leaf); |
2575 | free_extent_buffer(leaf); | |
be0e5c09 | 2576 | } |
d5719762 | 2577 | } else { |
5f39d397 | 2578 | btrfs_mark_buffer_dirty(leaf); |
be0e5c09 CM |
2579 | } |
2580 | } | |
aa5d6bed | 2581 | return ret; |
be0e5c09 CM |
2582 | } |
2583 | ||
7bb86316 CM |
2584 | /* |
2585 | * walk up the tree as far as required to find the previous leaf. | |
2586 | * returns 0 if it found something or 1 if there are no lesser leaves. | |
2587 | * returns < 0 on io errors. | |
2588 | */ | |
2589 | int btrfs_prev_leaf(struct btrfs_root *root, struct btrfs_path *path) | |
2590 | { | |
2591 | int slot; | |
2592 | int level = 1; | |
2593 | u64 bytenr; | |
2594 | struct extent_buffer *c; | |
2595 | struct extent_buffer *next = NULL; | |
2596 | ||
2597 | while(level < BTRFS_MAX_LEVEL) { | |
2598 | if (!path->nodes[level]) | |
2599 | return 1; | |
2600 | ||
2601 | slot = path->slots[level]; | |
2602 | c = path->nodes[level]; | |
2603 | if (slot == 0) { | |
2604 | level++; | |
2605 | if (level == BTRFS_MAX_LEVEL) | |
2606 | return 1; | |
2607 | continue; | |
2608 | } | |
2609 | slot--; | |
2610 | ||
2611 | bytenr = btrfs_node_blockptr(c, slot); | |
2612 | if (next) | |
2613 | free_extent_buffer(next); | |
2614 | ||
2615 | if (path->reada < 0) | |
2616 | reada_for_search(root, path, level, slot); | |
2617 | ||
2618 | next = read_tree_block(root, bytenr, | |
2619 | btrfs_level_size(root, level - 1)); | |
2620 | break; | |
2621 | } | |
2622 | path->slots[level] = slot; | |
2623 | while(1) { | |
2624 | level--; | |
2625 | c = path->nodes[level]; | |
2626 | free_extent_buffer(c); | |
2627 | path->nodes[level] = next; | |
2628 | path->slots[level] = 0; | |
2629 | if (!level) | |
2630 | break; | |
2631 | if (path->reada) | |
2632 | reada_for_search(root, path, level, 0); | |
2633 | next = read_tree_block(root, btrfs_node_blockptr(next, 0), | |
2634 | btrfs_level_size(root, level - 1)); | |
2635 | } | |
2636 | return 0; | |
2637 | } | |
2638 | ||
97571fd0 CM |
2639 | /* |
2640 | * walk up the tree as far as required to find the next leaf. | |
0f70abe2 CM |
2641 | * returns 0 if it found something or 1 if there are no greater leaves. |
2642 | * returns < 0 on io errors. | |
97571fd0 | 2643 | */ |
234b63a0 | 2644 | int btrfs_next_leaf(struct btrfs_root *root, struct btrfs_path *path) |
d97e63b6 CM |
2645 | { |
2646 | int slot; | |
2647 | int level = 1; | |
db94535d | 2648 | u64 bytenr; |
5f39d397 CM |
2649 | struct extent_buffer *c; |
2650 | struct extent_buffer *next = NULL; | |
d97e63b6 | 2651 | |
234b63a0 | 2652 | while(level < BTRFS_MAX_LEVEL) { |
d97e63b6 | 2653 | if (!path->nodes[level]) |
0f70abe2 | 2654 | return 1; |
5f39d397 | 2655 | |
d97e63b6 CM |
2656 | slot = path->slots[level] + 1; |
2657 | c = path->nodes[level]; | |
5f39d397 | 2658 | if (slot >= btrfs_header_nritems(c)) { |
d97e63b6 | 2659 | level++; |
7bb86316 CM |
2660 | if (level == BTRFS_MAX_LEVEL) |
2661 | return 1; | |
d97e63b6 CM |
2662 | continue; |
2663 | } | |
5f39d397 | 2664 | |
db94535d | 2665 | bytenr = btrfs_node_blockptr(c, slot); |
cfaa7295 | 2666 | if (next) |
5f39d397 CM |
2667 | free_extent_buffer(next); |
2668 | ||
6702ed49 CM |
2669 | if (path->reada) |
2670 | reada_for_search(root, path, level, slot); | |
5f39d397 | 2671 | |
db94535d CM |
2672 | next = read_tree_block(root, bytenr, |
2673 | btrfs_level_size(root, level -1)); | |
d97e63b6 CM |
2674 | break; |
2675 | } | |
2676 | path->slots[level] = slot; | |
2677 | while(1) { | |
2678 | level--; | |
2679 | c = path->nodes[level]; | |
5f39d397 | 2680 | free_extent_buffer(c); |
d97e63b6 CM |
2681 | path->nodes[level] = next; |
2682 | path->slots[level] = 0; | |
2683 | if (!level) | |
2684 | break; | |
6702ed49 | 2685 | if (path->reada) |
32020611 | 2686 | reada_for_search(root, path, level, 0); |
db94535d CM |
2687 | next = read_tree_block(root, btrfs_node_blockptr(next, 0), |
2688 | btrfs_level_size(root, level - 1)); | |
d97e63b6 CM |
2689 | } |
2690 | return 0; | |
2691 | } |