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6cbd5570 | 1 | /* |
d352ac68 | 2 | * Copyright (C) 2007,2008 Oracle. All rights reserved. |
6cbd5570 CM |
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" |
925baedd | 24 | #include "locking.h" |
9a8dd150 | 25 | |
e089f05c CM |
26 | static int split_node(struct btrfs_trans_handle *trans, struct btrfs_root |
27 | *root, struct btrfs_path *path, int level); | |
28 | static int split_leaf(struct btrfs_trans_handle *trans, struct btrfs_root | |
d4dbff95 | 29 | *root, struct btrfs_key *ins_key, |
cc0c5538 | 30 | struct btrfs_path *path, int data_size, int extend); |
5f39d397 CM |
31 | static int push_node_left(struct btrfs_trans_handle *trans, |
32 | struct btrfs_root *root, struct extent_buffer *dst, | |
971a1f66 | 33 | struct extent_buffer *src, int empty); |
5f39d397 CM |
34 | static int balance_node_right(struct btrfs_trans_handle *trans, |
35 | struct btrfs_root *root, | |
36 | struct extent_buffer *dst_buf, | |
37 | struct extent_buffer *src_buf); | |
e089f05c CM |
38 | static int del_ptr(struct btrfs_trans_handle *trans, struct btrfs_root *root, |
39 | struct btrfs_path *path, int level, int slot); | |
ad48fd75 YZ |
40 | static int setup_items_for_insert(struct btrfs_trans_handle *trans, |
41 | struct btrfs_root *root, struct btrfs_path *path, | |
42 | struct btrfs_key *cpu_key, u32 *data_size, | |
43 | u32 total_data, u32 total_size, int nr); | |
44 | ||
d97e63b6 | 45 | |
df24a2b9 | 46 | struct btrfs_path *btrfs_alloc_path(void) |
2c90e5d6 | 47 | { |
df24a2b9 | 48 | struct btrfs_path *path; |
e00f7308 JM |
49 | path = kmem_cache_zalloc(btrfs_path_cachep, GFP_NOFS); |
50 | if (path) | |
2cc58cf2 | 51 | path->reada = 1; |
df24a2b9 | 52 | return path; |
2c90e5d6 CM |
53 | } |
54 | ||
b4ce94de CM |
55 | /* |
56 | * set all locked nodes in the path to blocking locks. This should | |
57 | * be done before scheduling | |
58 | */ | |
59 | noinline void btrfs_set_path_blocking(struct btrfs_path *p) | |
60 | { | |
61 | int i; | |
62 | for (i = 0; i < BTRFS_MAX_LEVEL; i++) { | |
63 | if (p->nodes[i] && p->locks[i]) | |
64 | btrfs_set_lock_blocking(p->nodes[i]); | |
65 | } | |
66 | } | |
67 | ||
68 | /* | |
69 | * reset all the locked nodes in the patch to spinning locks. | |
4008c04a CM |
70 | * |
71 | * held is used to keep lockdep happy, when lockdep is enabled | |
72 | * we set held to a blocking lock before we go around and | |
73 | * retake all the spinlocks in the path. You can safely use NULL | |
74 | * for held | |
b4ce94de | 75 | */ |
4008c04a CM |
76 | noinline void btrfs_clear_path_blocking(struct btrfs_path *p, |
77 | struct extent_buffer *held) | |
b4ce94de CM |
78 | { |
79 | int i; | |
4008c04a CM |
80 | |
81 | #ifdef CONFIG_DEBUG_LOCK_ALLOC | |
82 | /* lockdep really cares that we take all of these spinlocks | |
83 | * in the right order. If any of the locks in the path are not | |
84 | * currently blocking, it is going to complain. So, make really | |
85 | * really sure by forcing the path to blocking before we clear | |
86 | * the path blocking. | |
87 | */ | |
88 | if (held) | |
89 | btrfs_set_lock_blocking(held); | |
90 | btrfs_set_path_blocking(p); | |
91 | #endif | |
92 | ||
93 | for (i = BTRFS_MAX_LEVEL - 1; i >= 0; i--) { | |
b4ce94de CM |
94 | if (p->nodes[i] && p->locks[i]) |
95 | btrfs_clear_lock_blocking(p->nodes[i]); | |
96 | } | |
4008c04a CM |
97 | |
98 | #ifdef CONFIG_DEBUG_LOCK_ALLOC | |
99 | if (held) | |
100 | btrfs_clear_lock_blocking(held); | |
101 | #endif | |
b4ce94de CM |
102 | } |
103 | ||
d352ac68 | 104 | /* this also releases the path */ |
df24a2b9 | 105 | void btrfs_free_path(struct btrfs_path *p) |
be0e5c09 | 106 | { |
df24a2b9 CM |
107 | btrfs_release_path(NULL, p); |
108 | kmem_cache_free(btrfs_path_cachep, p); | |
be0e5c09 CM |
109 | } |
110 | ||
d352ac68 CM |
111 | /* |
112 | * path release drops references on the extent buffers in the path | |
113 | * and it drops any locks held by this path | |
114 | * | |
115 | * It is safe to call this on paths that no locks or extent buffers held. | |
116 | */ | |
d397712b | 117 | noinline void btrfs_release_path(struct btrfs_root *root, struct btrfs_path *p) |
eb60ceac CM |
118 | { |
119 | int i; | |
a2135011 | 120 | |
234b63a0 | 121 | for (i = 0; i < BTRFS_MAX_LEVEL; i++) { |
3f157a2f | 122 | p->slots[i] = 0; |
eb60ceac | 123 | if (!p->nodes[i]) |
925baedd CM |
124 | continue; |
125 | if (p->locks[i]) { | |
126 | btrfs_tree_unlock(p->nodes[i]); | |
127 | p->locks[i] = 0; | |
128 | } | |
5f39d397 | 129 | free_extent_buffer(p->nodes[i]); |
3f157a2f | 130 | p->nodes[i] = NULL; |
eb60ceac CM |
131 | } |
132 | } | |
133 | ||
d352ac68 CM |
134 | /* |
135 | * safely gets a reference on the root node of a tree. A lock | |
136 | * is not taken, so a concurrent writer may put a different node | |
137 | * at the root of the tree. See btrfs_lock_root_node for the | |
138 | * looping required. | |
139 | * | |
140 | * The extent buffer returned by this has a reference taken, so | |
141 | * it won't disappear. It may stop being the root of the tree | |
142 | * at any time because there are no locks held. | |
143 | */ | |
925baedd CM |
144 | struct extent_buffer *btrfs_root_node(struct btrfs_root *root) |
145 | { | |
146 | struct extent_buffer *eb; | |
147 | spin_lock(&root->node_lock); | |
148 | eb = root->node; | |
149 | extent_buffer_get(eb); | |
150 | spin_unlock(&root->node_lock); | |
151 | return eb; | |
152 | } | |
153 | ||
d352ac68 CM |
154 | /* loop around taking references on and locking the root node of the |
155 | * tree until you end up with a lock on the root. A locked buffer | |
156 | * is returned, with a reference held. | |
157 | */ | |
925baedd CM |
158 | struct extent_buffer *btrfs_lock_root_node(struct btrfs_root *root) |
159 | { | |
160 | struct extent_buffer *eb; | |
161 | ||
d397712b | 162 | while (1) { |
925baedd CM |
163 | eb = btrfs_root_node(root); |
164 | btrfs_tree_lock(eb); | |
165 | ||
166 | spin_lock(&root->node_lock); | |
167 | if (eb == root->node) { | |
168 | spin_unlock(&root->node_lock); | |
169 | break; | |
170 | } | |
171 | spin_unlock(&root->node_lock); | |
172 | ||
173 | btrfs_tree_unlock(eb); | |
174 | free_extent_buffer(eb); | |
175 | } | |
176 | return eb; | |
177 | } | |
178 | ||
d352ac68 CM |
179 | /* cowonly root (everything not a reference counted cow subvolume), just get |
180 | * put onto a simple dirty list. transaction.c walks this to make sure they | |
181 | * get properly updated on disk. | |
182 | */ | |
0b86a832 CM |
183 | static void add_root_to_dirty_list(struct btrfs_root *root) |
184 | { | |
185 | if (root->track_dirty && list_empty(&root->dirty_list)) { | |
186 | list_add(&root->dirty_list, | |
187 | &root->fs_info->dirty_cowonly_roots); | |
188 | } | |
189 | } | |
190 | ||
d352ac68 CM |
191 | /* |
192 | * used by snapshot creation to make a copy of a root for a tree with | |
193 | * a given objectid. The buffer with the new root node is returned in | |
194 | * cow_ret, and this func returns zero on success or a negative error code. | |
195 | */ | |
be20aa9d CM |
196 | int btrfs_copy_root(struct btrfs_trans_handle *trans, |
197 | struct btrfs_root *root, | |
198 | struct extent_buffer *buf, | |
199 | struct extent_buffer **cow_ret, u64 new_root_objectid) | |
200 | { | |
201 | struct extent_buffer *cow; | |
202 | u32 nritems; | |
203 | int ret = 0; | |
204 | int level; | |
5d4f98a2 | 205 | struct btrfs_disk_key disk_key; |
be20aa9d CM |
206 | |
207 | WARN_ON(root->ref_cows && trans->transid != | |
208 | root->fs_info->running_transaction->transid); | |
209 | WARN_ON(root->ref_cows && trans->transid != root->last_trans); | |
210 | ||
211 | level = btrfs_header_level(buf); | |
212 | nritems = btrfs_header_nritems(buf); | |
5d4f98a2 YZ |
213 | if (level == 0) |
214 | btrfs_item_key(buf, &disk_key, 0); | |
215 | else | |
216 | btrfs_node_key(buf, &disk_key, 0); | |
31840ae1 | 217 | |
5d4f98a2 YZ |
218 | cow = btrfs_alloc_free_block(trans, root, buf->len, 0, |
219 | new_root_objectid, &disk_key, level, | |
220 | buf->start, 0); | |
221 | if (IS_ERR(cow)) | |
be20aa9d CM |
222 | return PTR_ERR(cow); |
223 | ||
224 | copy_extent_buffer(cow, buf, 0, 0, cow->len); | |
225 | btrfs_set_header_bytenr(cow, cow->start); | |
226 | btrfs_set_header_generation(cow, trans->transid); | |
5d4f98a2 YZ |
227 | btrfs_set_header_backref_rev(cow, BTRFS_MIXED_BACKREF_REV); |
228 | btrfs_clear_header_flag(cow, BTRFS_HEADER_FLAG_WRITTEN | | |
229 | BTRFS_HEADER_FLAG_RELOC); | |
230 | if (new_root_objectid == BTRFS_TREE_RELOC_OBJECTID) | |
231 | btrfs_set_header_flag(cow, BTRFS_HEADER_FLAG_RELOC); | |
232 | else | |
233 | btrfs_set_header_owner(cow, new_root_objectid); | |
be20aa9d | 234 | |
2b82032c YZ |
235 | write_extent_buffer(cow, root->fs_info->fsid, |
236 | (unsigned long)btrfs_header_fsid(cow), | |
237 | BTRFS_FSID_SIZE); | |
238 | ||
be20aa9d | 239 | WARN_ON(btrfs_header_generation(buf) > trans->transid); |
5d4f98a2 YZ |
240 | if (new_root_objectid == BTRFS_TREE_RELOC_OBJECTID) |
241 | ret = btrfs_inc_ref(trans, root, cow, 1); | |
242 | else | |
243 | ret = btrfs_inc_ref(trans, root, cow, 0); | |
4aec2b52 | 244 | |
be20aa9d CM |
245 | if (ret) |
246 | return ret; | |
247 | ||
248 | btrfs_mark_buffer_dirty(cow); | |
249 | *cow_ret = cow; | |
250 | return 0; | |
251 | } | |
252 | ||
5d4f98a2 YZ |
253 | /* |
254 | * check if the tree block can be shared by multiple trees | |
255 | */ | |
256 | int btrfs_block_can_be_shared(struct btrfs_root *root, | |
257 | struct extent_buffer *buf) | |
258 | { | |
259 | /* | |
260 | * Tree blocks not in refernece counted trees and tree roots | |
261 | * are never shared. If a block was allocated after the last | |
262 | * snapshot and the block was not allocated by tree relocation, | |
263 | * we know the block is not shared. | |
264 | */ | |
265 | if (root->ref_cows && | |
266 | buf != root->node && buf != root->commit_root && | |
267 | (btrfs_header_generation(buf) <= | |
268 | btrfs_root_last_snapshot(&root->root_item) || | |
269 | btrfs_header_flag(buf, BTRFS_HEADER_FLAG_RELOC))) | |
270 | return 1; | |
271 | #ifdef BTRFS_COMPAT_EXTENT_TREE_V0 | |
272 | if (root->ref_cows && | |
273 | btrfs_header_backref_rev(buf) < BTRFS_MIXED_BACKREF_REV) | |
274 | return 1; | |
275 | #endif | |
276 | return 0; | |
277 | } | |
278 | ||
279 | static noinline int update_ref_for_cow(struct btrfs_trans_handle *trans, | |
280 | struct btrfs_root *root, | |
281 | struct extent_buffer *buf, | |
282 | struct extent_buffer *cow) | |
283 | { | |
284 | u64 refs; | |
285 | u64 owner; | |
286 | u64 flags; | |
287 | u64 new_flags = 0; | |
288 | int ret; | |
289 | ||
290 | /* | |
291 | * Backrefs update rules: | |
292 | * | |
293 | * Always use full backrefs for extent pointers in tree block | |
294 | * allocated by tree relocation. | |
295 | * | |
296 | * If a shared tree block is no longer referenced by its owner | |
297 | * tree (btrfs_header_owner(buf) == root->root_key.objectid), | |
298 | * use full backrefs for extent pointers in tree block. | |
299 | * | |
300 | * If a tree block is been relocating | |
301 | * (root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID), | |
302 | * use full backrefs for extent pointers in tree block. | |
303 | * The reason for this is some operations (such as drop tree) | |
304 | * are only allowed for blocks use full backrefs. | |
305 | */ | |
306 | ||
307 | if (btrfs_block_can_be_shared(root, buf)) { | |
308 | ret = btrfs_lookup_extent_info(trans, root, buf->start, | |
309 | buf->len, &refs, &flags); | |
310 | BUG_ON(ret); | |
311 | BUG_ON(refs == 0); | |
312 | } else { | |
313 | refs = 1; | |
314 | if (root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID || | |
315 | btrfs_header_backref_rev(buf) < BTRFS_MIXED_BACKREF_REV) | |
316 | flags = BTRFS_BLOCK_FLAG_FULL_BACKREF; | |
317 | else | |
318 | flags = 0; | |
319 | } | |
320 | ||
321 | owner = btrfs_header_owner(buf); | |
322 | BUG_ON(owner == BTRFS_TREE_RELOC_OBJECTID && | |
323 | !(flags & BTRFS_BLOCK_FLAG_FULL_BACKREF)); | |
324 | ||
325 | if (refs > 1) { | |
326 | if ((owner == root->root_key.objectid || | |
327 | root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID) && | |
328 | !(flags & BTRFS_BLOCK_FLAG_FULL_BACKREF)) { | |
329 | ret = btrfs_inc_ref(trans, root, buf, 1); | |
330 | BUG_ON(ret); | |
331 | ||
332 | if (root->root_key.objectid == | |
333 | BTRFS_TREE_RELOC_OBJECTID) { | |
334 | ret = btrfs_dec_ref(trans, root, buf, 0); | |
335 | BUG_ON(ret); | |
336 | ret = btrfs_inc_ref(trans, root, cow, 1); | |
337 | BUG_ON(ret); | |
338 | } | |
339 | new_flags |= BTRFS_BLOCK_FLAG_FULL_BACKREF; | |
340 | } else { | |
341 | ||
342 | if (root->root_key.objectid == | |
343 | BTRFS_TREE_RELOC_OBJECTID) | |
344 | ret = btrfs_inc_ref(trans, root, cow, 1); | |
345 | else | |
346 | ret = btrfs_inc_ref(trans, root, cow, 0); | |
347 | BUG_ON(ret); | |
348 | } | |
349 | if (new_flags != 0) { | |
350 | ret = btrfs_set_disk_extent_flags(trans, root, | |
351 | buf->start, | |
352 | buf->len, | |
353 | new_flags, 0); | |
354 | BUG_ON(ret); | |
355 | } | |
356 | } else { | |
357 | if (flags & BTRFS_BLOCK_FLAG_FULL_BACKREF) { | |
358 | if (root->root_key.objectid == | |
359 | BTRFS_TREE_RELOC_OBJECTID) | |
360 | ret = btrfs_inc_ref(trans, root, cow, 1); | |
361 | else | |
362 | ret = btrfs_inc_ref(trans, root, cow, 0); | |
363 | BUG_ON(ret); | |
364 | ret = btrfs_dec_ref(trans, root, buf, 1); | |
365 | BUG_ON(ret); | |
366 | } | |
367 | clean_tree_block(trans, root, buf); | |
368 | } | |
369 | return 0; | |
370 | } | |
371 | ||
d352ac68 | 372 | /* |
d397712b CM |
373 | * does the dirty work in cow of a single block. The parent block (if |
374 | * supplied) is updated to point to the new cow copy. The new buffer is marked | |
375 | * dirty and returned locked. If you modify the block it needs to be marked | |
376 | * dirty again. | |
d352ac68 CM |
377 | * |
378 | * search_start -- an allocation hint for the new block | |
379 | * | |
d397712b CM |
380 | * empty_size -- a hint that you plan on doing more cow. This is the size in |
381 | * bytes the allocator should try to find free next to the block it returns. | |
382 | * This is just a hint and may be ignored by the allocator. | |
d352ac68 | 383 | */ |
d397712b | 384 | static noinline int __btrfs_cow_block(struct btrfs_trans_handle *trans, |
5f39d397 CM |
385 | struct btrfs_root *root, |
386 | struct extent_buffer *buf, | |
387 | struct extent_buffer *parent, int parent_slot, | |
388 | struct extent_buffer **cow_ret, | |
9fa8cfe7 | 389 | u64 search_start, u64 empty_size) |
02217ed2 | 390 | { |
5d4f98a2 | 391 | struct btrfs_disk_key disk_key; |
5f39d397 | 392 | struct extent_buffer *cow; |
7bb86316 | 393 | int level; |
925baedd | 394 | int unlock_orig = 0; |
5d4f98a2 | 395 | u64 parent_start; |
7bb86316 | 396 | |
925baedd CM |
397 | if (*cow_ret == buf) |
398 | unlock_orig = 1; | |
399 | ||
b9447ef8 | 400 | btrfs_assert_tree_locked(buf); |
925baedd | 401 | |
7bb86316 CM |
402 | WARN_ON(root->ref_cows && trans->transid != |
403 | root->fs_info->running_transaction->transid); | |
6702ed49 | 404 | WARN_ON(root->ref_cows && trans->transid != root->last_trans); |
5f39d397 | 405 | |
7bb86316 | 406 | level = btrfs_header_level(buf); |
31840ae1 | 407 | |
5d4f98a2 YZ |
408 | if (level == 0) |
409 | btrfs_item_key(buf, &disk_key, 0); | |
410 | else | |
411 | btrfs_node_key(buf, &disk_key, 0); | |
412 | ||
413 | if (root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID) { | |
414 | if (parent) | |
415 | parent_start = parent->start; | |
416 | else | |
417 | parent_start = 0; | |
418 | } else | |
419 | parent_start = 0; | |
420 | ||
421 | cow = btrfs_alloc_free_block(trans, root, buf->len, parent_start, | |
422 | root->root_key.objectid, &disk_key, | |
423 | level, search_start, empty_size); | |
54aa1f4d CM |
424 | if (IS_ERR(cow)) |
425 | return PTR_ERR(cow); | |
6702ed49 | 426 | |
b4ce94de CM |
427 | /* cow is set to blocking by btrfs_init_new_buffer */ |
428 | ||
5f39d397 | 429 | copy_extent_buffer(cow, buf, 0, 0, cow->len); |
db94535d | 430 | btrfs_set_header_bytenr(cow, cow->start); |
5f39d397 | 431 | btrfs_set_header_generation(cow, trans->transid); |
5d4f98a2 YZ |
432 | btrfs_set_header_backref_rev(cow, BTRFS_MIXED_BACKREF_REV); |
433 | btrfs_clear_header_flag(cow, BTRFS_HEADER_FLAG_WRITTEN | | |
434 | BTRFS_HEADER_FLAG_RELOC); | |
435 | if (root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID) | |
436 | btrfs_set_header_flag(cow, BTRFS_HEADER_FLAG_RELOC); | |
437 | else | |
438 | btrfs_set_header_owner(cow, root->root_key.objectid); | |
6702ed49 | 439 | |
2b82032c YZ |
440 | write_extent_buffer(cow, root->fs_info->fsid, |
441 | (unsigned long)btrfs_header_fsid(cow), | |
442 | BTRFS_FSID_SIZE); | |
443 | ||
5d4f98a2 | 444 | update_ref_for_cow(trans, root, buf, cow); |
1a40e23b | 445 | |
02217ed2 | 446 | if (buf == root->node) { |
925baedd | 447 | WARN_ON(parent && parent != buf); |
5d4f98a2 YZ |
448 | if (root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID || |
449 | btrfs_header_backref_rev(buf) < BTRFS_MIXED_BACKREF_REV) | |
450 | parent_start = buf->start; | |
451 | else | |
452 | parent_start = 0; | |
925baedd CM |
453 | |
454 | spin_lock(&root->node_lock); | |
02217ed2 | 455 | root->node = cow; |
5f39d397 | 456 | extent_buffer_get(cow); |
925baedd CM |
457 | spin_unlock(&root->node_lock); |
458 | ||
86b9f2ec YZ |
459 | btrfs_free_tree_block(trans, root, buf->start, buf->len, |
460 | parent_start, root->root_key.objectid, level); | |
5f39d397 | 461 | free_extent_buffer(buf); |
0b86a832 | 462 | add_root_to_dirty_list(root); |
02217ed2 | 463 | } else { |
5d4f98a2 YZ |
464 | if (root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID) |
465 | parent_start = parent->start; | |
466 | else | |
467 | parent_start = 0; | |
468 | ||
469 | WARN_ON(trans->transid != btrfs_header_generation(parent)); | |
5f39d397 | 470 | btrfs_set_node_blockptr(parent, parent_slot, |
db94535d | 471 | cow->start); |
74493f7a CM |
472 | btrfs_set_node_ptr_generation(parent, parent_slot, |
473 | trans->transid); | |
d6025579 | 474 | btrfs_mark_buffer_dirty(parent); |
86b9f2ec YZ |
475 | btrfs_free_tree_block(trans, root, buf->start, buf->len, |
476 | parent_start, root->root_key.objectid, level); | |
02217ed2 | 477 | } |
925baedd CM |
478 | if (unlock_orig) |
479 | btrfs_tree_unlock(buf); | |
5f39d397 | 480 | free_extent_buffer(buf); |
ccd467d6 | 481 | btrfs_mark_buffer_dirty(cow); |
2c90e5d6 | 482 | *cow_ret = cow; |
02217ed2 CM |
483 | return 0; |
484 | } | |
485 | ||
5d4f98a2 YZ |
486 | static inline int should_cow_block(struct btrfs_trans_handle *trans, |
487 | struct btrfs_root *root, | |
488 | struct extent_buffer *buf) | |
489 | { | |
490 | if (btrfs_header_generation(buf) == trans->transid && | |
491 | !btrfs_header_flag(buf, BTRFS_HEADER_FLAG_WRITTEN) && | |
492 | !(root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID && | |
493 | btrfs_header_flag(buf, BTRFS_HEADER_FLAG_RELOC))) | |
494 | return 0; | |
495 | return 1; | |
496 | } | |
497 | ||
d352ac68 CM |
498 | /* |
499 | * cows a single block, see __btrfs_cow_block for the real work. | |
500 | * This version of it has extra checks so that a block isn't cow'd more than | |
501 | * once per transaction, as long as it hasn't been written yet | |
502 | */ | |
d397712b | 503 | noinline int btrfs_cow_block(struct btrfs_trans_handle *trans, |
5f39d397 CM |
504 | struct btrfs_root *root, struct extent_buffer *buf, |
505 | struct extent_buffer *parent, int parent_slot, | |
9fa8cfe7 | 506 | struct extent_buffer **cow_ret) |
6702ed49 CM |
507 | { |
508 | u64 search_start; | |
f510cfec | 509 | int ret; |
dc17ff8f | 510 | |
6702ed49 | 511 | if (trans->transaction != root->fs_info->running_transaction) { |
d397712b CM |
512 | printk(KERN_CRIT "trans %llu running %llu\n", |
513 | (unsigned long long)trans->transid, | |
514 | (unsigned long long) | |
6702ed49 CM |
515 | root->fs_info->running_transaction->transid); |
516 | WARN_ON(1); | |
517 | } | |
518 | if (trans->transid != root->fs_info->generation) { | |
d397712b CM |
519 | printk(KERN_CRIT "trans %llu running %llu\n", |
520 | (unsigned long long)trans->transid, | |
521 | (unsigned long long)root->fs_info->generation); | |
6702ed49 CM |
522 | WARN_ON(1); |
523 | } | |
dc17ff8f | 524 | |
5d4f98a2 | 525 | if (!should_cow_block(trans, root, buf)) { |
6702ed49 CM |
526 | *cow_ret = buf; |
527 | return 0; | |
528 | } | |
c487685d | 529 | |
0b86a832 | 530 | search_start = buf->start & ~((u64)(1024 * 1024 * 1024) - 1); |
b4ce94de CM |
531 | |
532 | if (parent) | |
533 | btrfs_set_lock_blocking(parent); | |
534 | btrfs_set_lock_blocking(buf); | |
535 | ||
f510cfec | 536 | ret = __btrfs_cow_block(trans, root, buf, parent, |
9fa8cfe7 | 537 | parent_slot, cow_ret, search_start, 0); |
f510cfec | 538 | return ret; |
6702ed49 CM |
539 | } |
540 | ||
d352ac68 CM |
541 | /* |
542 | * helper function for defrag to decide if two blocks pointed to by a | |
543 | * node are actually close by | |
544 | */ | |
6b80053d | 545 | static int close_blocks(u64 blocknr, u64 other, u32 blocksize) |
6702ed49 | 546 | { |
6b80053d | 547 | if (blocknr < other && other - (blocknr + blocksize) < 32768) |
6702ed49 | 548 | return 1; |
6b80053d | 549 | if (blocknr > other && blocknr - (other + blocksize) < 32768) |
6702ed49 CM |
550 | return 1; |
551 | return 0; | |
552 | } | |
553 | ||
081e9573 CM |
554 | /* |
555 | * compare two keys in a memcmp fashion | |
556 | */ | |
557 | static int comp_keys(struct btrfs_disk_key *disk, struct btrfs_key *k2) | |
558 | { | |
559 | struct btrfs_key k1; | |
560 | ||
561 | btrfs_disk_key_to_cpu(&k1, disk); | |
562 | ||
20736aba | 563 | return btrfs_comp_cpu_keys(&k1, k2); |
081e9573 CM |
564 | } |
565 | ||
f3465ca4 JB |
566 | /* |
567 | * same as comp_keys only with two btrfs_key's | |
568 | */ | |
5d4f98a2 | 569 | int btrfs_comp_cpu_keys(struct btrfs_key *k1, struct btrfs_key *k2) |
f3465ca4 JB |
570 | { |
571 | if (k1->objectid > k2->objectid) | |
572 | return 1; | |
573 | if (k1->objectid < k2->objectid) | |
574 | return -1; | |
575 | if (k1->type > k2->type) | |
576 | return 1; | |
577 | if (k1->type < k2->type) | |
578 | return -1; | |
579 | if (k1->offset > k2->offset) | |
580 | return 1; | |
581 | if (k1->offset < k2->offset) | |
582 | return -1; | |
583 | return 0; | |
584 | } | |
081e9573 | 585 | |
d352ac68 CM |
586 | /* |
587 | * this is used by the defrag code to go through all the | |
588 | * leaves pointed to by a node and reallocate them so that | |
589 | * disk order is close to key order | |
590 | */ | |
6702ed49 | 591 | int btrfs_realloc_node(struct btrfs_trans_handle *trans, |
5f39d397 | 592 | struct btrfs_root *root, struct extent_buffer *parent, |
a6b6e75e CM |
593 | int start_slot, int cache_only, u64 *last_ret, |
594 | struct btrfs_key *progress) | |
6702ed49 | 595 | { |
6b80053d | 596 | struct extent_buffer *cur; |
6702ed49 | 597 | u64 blocknr; |
ca7a79ad | 598 | u64 gen; |
e9d0b13b CM |
599 | u64 search_start = *last_ret; |
600 | u64 last_block = 0; | |
6702ed49 CM |
601 | u64 other; |
602 | u32 parent_nritems; | |
6702ed49 CM |
603 | int end_slot; |
604 | int i; | |
605 | int err = 0; | |
f2183bde | 606 | int parent_level; |
6b80053d CM |
607 | int uptodate; |
608 | u32 blocksize; | |
081e9573 CM |
609 | int progress_passed = 0; |
610 | struct btrfs_disk_key disk_key; | |
6702ed49 | 611 | |
5708b959 CM |
612 | parent_level = btrfs_header_level(parent); |
613 | if (cache_only && parent_level != 1) | |
614 | return 0; | |
615 | ||
d397712b | 616 | if (trans->transaction != root->fs_info->running_transaction) |
6702ed49 | 617 | WARN_ON(1); |
d397712b | 618 | if (trans->transid != root->fs_info->generation) |
6702ed49 | 619 | WARN_ON(1); |
86479a04 | 620 | |
6b80053d | 621 | parent_nritems = btrfs_header_nritems(parent); |
6b80053d | 622 | blocksize = btrfs_level_size(root, parent_level - 1); |
6702ed49 CM |
623 | end_slot = parent_nritems; |
624 | ||
625 | if (parent_nritems == 1) | |
626 | return 0; | |
627 | ||
b4ce94de CM |
628 | btrfs_set_lock_blocking(parent); |
629 | ||
6702ed49 CM |
630 | for (i = start_slot; i < end_slot; i++) { |
631 | int close = 1; | |
a6b6e75e | 632 | |
5708b959 CM |
633 | if (!parent->map_token) { |
634 | map_extent_buffer(parent, | |
635 | btrfs_node_key_ptr_offset(i), | |
636 | sizeof(struct btrfs_key_ptr), | |
637 | &parent->map_token, &parent->kaddr, | |
638 | &parent->map_start, &parent->map_len, | |
639 | KM_USER1); | |
640 | } | |
081e9573 CM |
641 | btrfs_node_key(parent, &disk_key, i); |
642 | if (!progress_passed && comp_keys(&disk_key, progress) < 0) | |
643 | continue; | |
644 | ||
645 | progress_passed = 1; | |
6b80053d | 646 | blocknr = btrfs_node_blockptr(parent, i); |
ca7a79ad | 647 | gen = btrfs_node_ptr_generation(parent, i); |
e9d0b13b CM |
648 | if (last_block == 0) |
649 | last_block = blocknr; | |
5708b959 | 650 | |
6702ed49 | 651 | if (i > 0) { |
6b80053d CM |
652 | other = btrfs_node_blockptr(parent, i - 1); |
653 | close = close_blocks(blocknr, other, blocksize); | |
6702ed49 | 654 | } |
0ef3e66b | 655 | if (!close && i < end_slot - 2) { |
6b80053d CM |
656 | other = btrfs_node_blockptr(parent, i + 1); |
657 | close = close_blocks(blocknr, other, blocksize); | |
6702ed49 | 658 | } |
e9d0b13b CM |
659 | if (close) { |
660 | last_block = blocknr; | |
6702ed49 | 661 | continue; |
e9d0b13b | 662 | } |
5708b959 CM |
663 | if (parent->map_token) { |
664 | unmap_extent_buffer(parent, parent->map_token, | |
665 | KM_USER1); | |
666 | parent->map_token = NULL; | |
667 | } | |
6702ed49 | 668 | |
6b80053d CM |
669 | cur = btrfs_find_tree_block(root, blocknr, blocksize); |
670 | if (cur) | |
1259ab75 | 671 | uptodate = btrfs_buffer_uptodate(cur, gen); |
6b80053d CM |
672 | else |
673 | uptodate = 0; | |
5708b959 | 674 | if (!cur || !uptodate) { |
6702ed49 | 675 | if (cache_only) { |
6b80053d | 676 | free_extent_buffer(cur); |
6702ed49 CM |
677 | continue; |
678 | } | |
6b80053d CM |
679 | if (!cur) { |
680 | cur = read_tree_block(root, blocknr, | |
ca7a79ad | 681 | blocksize, gen); |
6b80053d | 682 | } else if (!uptodate) { |
ca7a79ad | 683 | btrfs_read_buffer(cur, gen); |
f2183bde | 684 | } |
6702ed49 | 685 | } |
e9d0b13b | 686 | if (search_start == 0) |
6b80053d | 687 | search_start = last_block; |
e9d0b13b | 688 | |
e7a84565 | 689 | btrfs_tree_lock(cur); |
b4ce94de | 690 | btrfs_set_lock_blocking(cur); |
6b80053d | 691 | err = __btrfs_cow_block(trans, root, cur, parent, i, |
e7a84565 | 692 | &cur, search_start, |
6b80053d | 693 | min(16 * blocksize, |
9fa8cfe7 | 694 | (end_slot - i) * blocksize)); |
252c38f0 | 695 | if (err) { |
e7a84565 | 696 | btrfs_tree_unlock(cur); |
6b80053d | 697 | free_extent_buffer(cur); |
6702ed49 | 698 | break; |
252c38f0 | 699 | } |
e7a84565 CM |
700 | search_start = cur->start; |
701 | last_block = cur->start; | |
f2183bde | 702 | *last_ret = search_start; |
e7a84565 CM |
703 | btrfs_tree_unlock(cur); |
704 | free_extent_buffer(cur); | |
6702ed49 | 705 | } |
5708b959 CM |
706 | if (parent->map_token) { |
707 | unmap_extent_buffer(parent, parent->map_token, | |
708 | KM_USER1); | |
709 | parent->map_token = NULL; | |
710 | } | |
6702ed49 CM |
711 | return err; |
712 | } | |
713 | ||
74123bd7 CM |
714 | /* |
715 | * The leaf data grows from end-to-front in the node. | |
716 | * this returns the address of the start of the last item, | |
717 | * which is the stop of the leaf data stack | |
718 | */ | |
123abc88 | 719 | static inline unsigned int leaf_data_end(struct btrfs_root *root, |
5f39d397 | 720 | struct extent_buffer *leaf) |
be0e5c09 | 721 | { |
5f39d397 | 722 | u32 nr = btrfs_header_nritems(leaf); |
be0e5c09 | 723 | if (nr == 0) |
123abc88 | 724 | return BTRFS_LEAF_DATA_SIZE(root); |
5f39d397 | 725 | return btrfs_item_offset_nr(leaf, nr - 1); |
be0e5c09 CM |
726 | } |
727 | ||
d352ac68 CM |
728 | /* |
729 | * extra debugging checks to make sure all the items in a key are | |
730 | * well formed and in the proper order | |
731 | */ | |
123abc88 CM |
732 | static int check_node(struct btrfs_root *root, struct btrfs_path *path, |
733 | int level) | |
aa5d6bed | 734 | { |
5f39d397 CM |
735 | struct extent_buffer *parent = NULL; |
736 | struct extent_buffer *node = path->nodes[level]; | |
737 | struct btrfs_disk_key parent_key; | |
738 | struct btrfs_disk_key node_key; | |
aa5d6bed | 739 | int parent_slot; |
8d7be552 CM |
740 | int slot; |
741 | struct btrfs_key cpukey; | |
5f39d397 | 742 | u32 nritems = btrfs_header_nritems(node); |
aa5d6bed CM |
743 | |
744 | if (path->nodes[level + 1]) | |
5f39d397 | 745 | parent = path->nodes[level + 1]; |
a1f39630 | 746 | |
8d7be552 | 747 | slot = path->slots[level]; |
7518a238 CM |
748 | BUG_ON(nritems == 0); |
749 | if (parent) { | |
a1f39630 | 750 | parent_slot = path->slots[level + 1]; |
5f39d397 CM |
751 | btrfs_node_key(parent, &parent_key, parent_slot); |
752 | btrfs_node_key(node, &node_key, 0); | |
753 | BUG_ON(memcmp(&parent_key, &node_key, | |
e2fa7227 | 754 | sizeof(struct btrfs_disk_key))); |
1d4f8a0c | 755 | BUG_ON(btrfs_node_blockptr(parent, parent_slot) != |
db94535d | 756 | btrfs_header_bytenr(node)); |
aa5d6bed | 757 | } |
123abc88 | 758 | BUG_ON(nritems > BTRFS_NODEPTRS_PER_BLOCK(root)); |
8d7be552 | 759 | if (slot != 0) { |
5f39d397 CM |
760 | btrfs_node_key_to_cpu(node, &cpukey, slot - 1); |
761 | btrfs_node_key(node, &node_key, slot); | |
762 | BUG_ON(comp_keys(&node_key, &cpukey) <= 0); | |
8d7be552 CM |
763 | } |
764 | if (slot < nritems - 1) { | |
5f39d397 CM |
765 | btrfs_node_key_to_cpu(node, &cpukey, slot + 1); |
766 | btrfs_node_key(node, &node_key, slot); | |
767 | BUG_ON(comp_keys(&node_key, &cpukey) >= 0); | |
aa5d6bed CM |
768 | } |
769 | return 0; | |
770 | } | |
771 | ||
d352ac68 CM |
772 | /* |
773 | * extra checking to make sure all the items in a leaf are | |
774 | * well formed and in the proper order | |
775 | */ | |
123abc88 CM |
776 | static int check_leaf(struct btrfs_root *root, struct btrfs_path *path, |
777 | int level) | |
aa5d6bed | 778 | { |
5f39d397 CM |
779 | struct extent_buffer *leaf = path->nodes[level]; |
780 | struct extent_buffer *parent = NULL; | |
aa5d6bed | 781 | int parent_slot; |
8d7be552 | 782 | struct btrfs_key cpukey; |
5f39d397 CM |
783 | struct btrfs_disk_key parent_key; |
784 | struct btrfs_disk_key leaf_key; | |
785 | int slot = path->slots[0]; | |
8d7be552 | 786 | |
5f39d397 | 787 | u32 nritems = btrfs_header_nritems(leaf); |
aa5d6bed CM |
788 | |
789 | if (path->nodes[level + 1]) | |
5f39d397 | 790 | parent = path->nodes[level + 1]; |
7518a238 CM |
791 | |
792 | if (nritems == 0) | |
793 | return 0; | |
794 | ||
795 | if (parent) { | |
a1f39630 | 796 | parent_slot = path->slots[level + 1]; |
5f39d397 CM |
797 | btrfs_node_key(parent, &parent_key, parent_slot); |
798 | btrfs_item_key(leaf, &leaf_key, 0); | |
6702ed49 | 799 | |
5f39d397 | 800 | BUG_ON(memcmp(&parent_key, &leaf_key, |
e2fa7227 | 801 | sizeof(struct btrfs_disk_key))); |
1d4f8a0c | 802 | BUG_ON(btrfs_node_blockptr(parent, parent_slot) != |
db94535d | 803 | btrfs_header_bytenr(leaf)); |
5f39d397 | 804 | } |
5f39d397 CM |
805 | if (slot != 0 && slot < nritems - 1) { |
806 | btrfs_item_key(leaf, &leaf_key, slot); | |
807 | btrfs_item_key_to_cpu(leaf, &cpukey, slot - 1); | |
808 | if (comp_keys(&leaf_key, &cpukey) <= 0) { | |
809 | btrfs_print_leaf(root, leaf); | |
d397712b | 810 | printk(KERN_CRIT "slot %d offset bad key\n", slot); |
5f39d397 CM |
811 | BUG_ON(1); |
812 | } | |
813 | if (btrfs_item_offset_nr(leaf, slot - 1) != | |
814 | btrfs_item_end_nr(leaf, slot)) { | |
815 | btrfs_print_leaf(root, leaf); | |
d397712b | 816 | printk(KERN_CRIT "slot %d offset bad\n", slot); |
5f39d397 CM |
817 | BUG_ON(1); |
818 | } | |
8d7be552 CM |
819 | } |
820 | if (slot < nritems - 1) { | |
5f39d397 CM |
821 | btrfs_item_key(leaf, &leaf_key, slot); |
822 | btrfs_item_key_to_cpu(leaf, &cpukey, slot + 1); | |
823 | BUG_ON(comp_keys(&leaf_key, &cpukey) >= 0); | |
824 | if (btrfs_item_offset_nr(leaf, slot) != | |
825 | btrfs_item_end_nr(leaf, slot + 1)) { | |
826 | btrfs_print_leaf(root, leaf); | |
d397712b | 827 | printk(KERN_CRIT "slot %d offset bad\n", slot); |
5f39d397 CM |
828 | BUG_ON(1); |
829 | } | |
aa5d6bed | 830 | } |
5f39d397 CM |
831 | BUG_ON(btrfs_item_offset_nr(leaf, 0) + |
832 | btrfs_item_size_nr(leaf, 0) != BTRFS_LEAF_DATA_SIZE(root)); | |
aa5d6bed CM |
833 | return 0; |
834 | } | |
835 | ||
d397712b | 836 | static noinline int check_block(struct btrfs_root *root, |
98ed5174 | 837 | struct btrfs_path *path, int level) |
aa5d6bed | 838 | { |
85d824c4 | 839 | return 0; |
aa5d6bed | 840 | if (level == 0) |
123abc88 CM |
841 | return check_leaf(root, path, level); |
842 | return check_node(root, path, level); | |
aa5d6bed CM |
843 | } |
844 | ||
74123bd7 | 845 | /* |
5f39d397 CM |
846 | * search for key in the extent_buffer. The items start at offset p, |
847 | * and they are item_size apart. There are 'max' items in p. | |
848 | * | |
74123bd7 CM |
849 | * the slot in the array is returned via slot, and it points to |
850 | * the place where you would insert key if it is not found in | |
851 | * the array. | |
852 | * | |
853 | * slot may point to max if the key is bigger than all of the keys | |
854 | */ | |
e02119d5 CM |
855 | static noinline int generic_bin_search(struct extent_buffer *eb, |
856 | unsigned long p, | |
857 | int item_size, struct btrfs_key *key, | |
858 | int max, int *slot) | |
be0e5c09 CM |
859 | { |
860 | int low = 0; | |
861 | int high = max; | |
862 | int mid; | |
863 | int ret; | |
479965d6 | 864 | struct btrfs_disk_key *tmp = NULL; |
5f39d397 CM |
865 | struct btrfs_disk_key unaligned; |
866 | unsigned long offset; | |
867 | char *map_token = NULL; | |
868 | char *kaddr = NULL; | |
869 | unsigned long map_start = 0; | |
870 | unsigned long map_len = 0; | |
479965d6 | 871 | int err; |
be0e5c09 | 872 | |
d397712b | 873 | while (low < high) { |
be0e5c09 | 874 | mid = (low + high) / 2; |
5f39d397 CM |
875 | offset = p + mid * item_size; |
876 | ||
877 | if (!map_token || offset < map_start || | |
878 | (offset + sizeof(struct btrfs_disk_key)) > | |
879 | map_start + map_len) { | |
479965d6 | 880 | if (map_token) { |
5f39d397 | 881 | unmap_extent_buffer(eb, map_token, KM_USER0); |
479965d6 CM |
882 | map_token = NULL; |
883 | } | |
934d375b CM |
884 | |
885 | err = map_private_extent_buffer(eb, offset, | |
479965d6 CM |
886 | sizeof(struct btrfs_disk_key), |
887 | &map_token, &kaddr, | |
888 | &map_start, &map_len, KM_USER0); | |
889 | ||
890 | if (!err) { | |
891 | tmp = (struct btrfs_disk_key *)(kaddr + offset - | |
892 | map_start); | |
893 | } else { | |
894 | read_extent_buffer(eb, &unaligned, | |
895 | offset, sizeof(unaligned)); | |
896 | tmp = &unaligned; | |
897 | } | |
5f39d397 | 898 | |
5f39d397 CM |
899 | } else { |
900 | tmp = (struct btrfs_disk_key *)(kaddr + offset - | |
901 | map_start); | |
902 | } | |
be0e5c09 CM |
903 | ret = comp_keys(tmp, key); |
904 | ||
905 | if (ret < 0) | |
906 | low = mid + 1; | |
907 | else if (ret > 0) | |
908 | high = mid; | |
909 | else { | |
910 | *slot = mid; | |
479965d6 CM |
911 | if (map_token) |
912 | unmap_extent_buffer(eb, map_token, KM_USER0); | |
be0e5c09 CM |
913 | return 0; |
914 | } | |
915 | } | |
916 | *slot = low; | |
5f39d397 CM |
917 | if (map_token) |
918 | unmap_extent_buffer(eb, map_token, KM_USER0); | |
be0e5c09 CM |
919 | return 1; |
920 | } | |
921 | ||
97571fd0 CM |
922 | /* |
923 | * simple bin_search frontend that does the right thing for | |
924 | * leaves vs nodes | |
925 | */ | |
5f39d397 CM |
926 | static int bin_search(struct extent_buffer *eb, struct btrfs_key *key, |
927 | int level, int *slot) | |
be0e5c09 | 928 | { |
5f39d397 CM |
929 | if (level == 0) { |
930 | return generic_bin_search(eb, | |
931 | offsetof(struct btrfs_leaf, items), | |
0783fcfc | 932 | sizeof(struct btrfs_item), |
5f39d397 | 933 | key, btrfs_header_nritems(eb), |
7518a238 | 934 | slot); |
be0e5c09 | 935 | } else { |
5f39d397 CM |
936 | return generic_bin_search(eb, |
937 | offsetof(struct btrfs_node, ptrs), | |
123abc88 | 938 | sizeof(struct btrfs_key_ptr), |
5f39d397 | 939 | key, btrfs_header_nritems(eb), |
7518a238 | 940 | slot); |
be0e5c09 CM |
941 | } |
942 | return -1; | |
943 | } | |
944 | ||
5d4f98a2 YZ |
945 | int btrfs_bin_search(struct extent_buffer *eb, struct btrfs_key *key, |
946 | int level, int *slot) | |
947 | { | |
948 | return bin_search(eb, key, level, slot); | |
949 | } | |
950 | ||
d352ac68 CM |
951 | /* given a node and slot number, this reads the blocks it points to. The |
952 | * extent buffer is returned with a reference taken (but unlocked). | |
953 | * NULL is returned on error. | |
954 | */ | |
e02119d5 | 955 | static noinline struct extent_buffer *read_node_slot(struct btrfs_root *root, |
5f39d397 | 956 | struct extent_buffer *parent, int slot) |
bb803951 | 957 | { |
ca7a79ad | 958 | int level = btrfs_header_level(parent); |
bb803951 CM |
959 | if (slot < 0) |
960 | return NULL; | |
5f39d397 | 961 | if (slot >= btrfs_header_nritems(parent)) |
bb803951 | 962 | return NULL; |
ca7a79ad CM |
963 | |
964 | BUG_ON(level == 0); | |
965 | ||
db94535d | 966 | return read_tree_block(root, btrfs_node_blockptr(parent, slot), |
ca7a79ad CM |
967 | btrfs_level_size(root, level - 1), |
968 | btrfs_node_ptr_generation(parent, slot)); | |
bb803951 CM |
969 | } |
970 | ||
d352ac68 CM |
971 | /* |
972 | * node level balancing, used to make sure nodes are in proper order for | |
973 | * item deletion. We balance from the top down, so we have to make sure | |
974 | * that a deletion won't leave an node completely empty later on. | |
975 | */ | |
e02119d5 | 976 | static noinline int balance_level(struct btrfs_trans_handle *trans, |
98ed5174 CM |
977 | struct btrfs_root *root, |
978 | struct btrfs_path *path, int level) | |
bb803951 | 979 | { |
5f39d397 CM |
980 | struct extent_buffer *right = NULL; |
981 | struct extent_buffer *mid; | |
982 | struct extent_buffer *left = NULL; | |
983 | struct extent_buffer *parent = NULL; | |
bb803951 CM |
984 | int ret = 0; |
985 | int wret; | |
986 | int pslot; | |
bb803951 | 987 | int orig_slot = path->slots[level]; |
54aa1f4d | 988 | int err_on_enospc = 0; |
79f95c82 | 989 | u64 orig_ptr; |
bb803951 CM |
990 | |
991 | if (level == 0) | |
992 | return 0; | |
993 | ||
5f39d397 | 994 | mid = path->nodes[level]; |
b4ce94de | 995 | |
925baedd | 996 | WARN_ON(!path->locks[level]); |
7bb86316 CM |
997 | WARN_ON(btrfs_header_generation(mid) != trans->transid); |
998 | ||
1d4f8a0c | 999 | orig_ptr = btrfs_node_blockptr(mid, orig_slot); |
79f95c82 | 1000 | |
234b63a0 | 1001 | if (level < BTRFS_MAX_LEVEL - 1) |
5f39d397 | 1002 | parent = path->nodes[level + 1]; |
bb803951 CM |
1003 | pslot = path->slots[level + 1]; |
1004 | ||
40689478 CM |
1005 | /* |
1006 | * deal with the case where there is only one pointer in the root | |
1007 | * by promoting the node below to a root | |
1008 | */ | |
5f39d397 CM |
1009 | if (!parent) { |
1010 | struct extent_buffer *child; | |
bb803951 | 1011 | |
5f39d397 | 1012 | if (btrfs_header_nritems(mid) != 1) |
bb803951 CM |
1013 | return 0; |
1014 | ||
1015 | /* promote the child to a root */ | |
5f39d397 | 1016 | child = read_node_slot(root, mid, 0); |
7951f3ce | 1017 | BUG_ON(!child); |
925baedd | 1018 | btrfs_tree_lock(child); |
b4ce94de | 1019 | btrfs_set_lock_blocking(child); |
9fa8cfe7 | 1020 | ret = btrfs_cow_block(trans, root, child, mid, 0, &child); |
2f375ab9 Y |
1021 | BUG_ON(ret); |
1022 | ||
925baedd | 1023 | spin_lock(&root->node_lock); |
bb803951 | 1024 | root->node = child; |
925baedd CM |
1025 | spin_unlock(&root->node_lock); |
1026 | ||
0b86a832 | 1027 | add_root_to_dirty_list(root); |
925baedd | 1028 | btrfs_tree_unlock(child); |
b4ce94de | 1029 | |
925baedd | 1030 | path->locks[level] = 0; |
bb803951 | 1031 | path->nodes[level] = NULL; |
5f39d397 | 1032 | clean_tree_block(trans, root, mid); |
925baedd | 1033 | btrfs_tree_unlock(mid); |
bb803951 | 1034 | /* once for the path */ |
5f39d397 | 1035 | free_extent_buffer(mid); |
86b9f2ec YZ |
1036 | ret = btrfs_free_tree_block(trans, root, mid->start, mid->len, |
1037 | 0, root->root_key.objectid, level); | |
bb803951 | 1038 | /* once for the root ptr */ |
5f39d397 | 1039 | free_extent_buffer(mid); |
db94535d | 1040 | return ret; |
bb803951 | 1041 | } |
5f39d397 | 1042 | if (btrfs_header_nritems(mid) > |
123abc88 | 1043 | BTRFS_NODEPTRS_PER_BLOCK(root) / 4) |
bb803951 CM |
1044 | return 0; |
1045 | ||
5f39d397 | 1046 | if (btrfs_header_nritems(mid) < 2) |
54aa1f4d CM |
1047 | err_on_enospc = 1; |
1048 | ||
5f39d397 CM |
1049 | left = read_node_slot(root, parent, pslot - 1); |
1050 | if (left) { | |
925baedd | 1051 | btrfs_tree_lock(left); |
b4ce94de | 1052 | btrfs_set_lock_blocking(left); |
5f39d397 | 1053 | wret = btrfs_cow_block(trans, root, left, |
9fa8cfe7 | 1054 | parent, pslot - 1, &left); |
54aa1f4d CM |
1055 | if (wret) { |
1056 | ret = wret; | |
1057 | goto enospc; | |
1058 | } | |
2cc58cf2 | 1059 | } |
5f39d397 CM |
1060 | right = read_node_slot(root, parent, pslot + 1); |
1061 | if (right) { | |
925baedd | 1062 | btrfs_tree_lock(right); |
b4ce94de | 1063 | btrfs_set_lock_blocking(right); |
5f39d397 | 1064 | wret = btrfs_cow_block(trans, root, right, |
9fa8cfe7 | 1065 | parent, pslot + 1, &right); |
2cc58cf2 CM |
1066 | if (wret) { |
1067 | ret = wret; | |
1068 | goto enospc; | |
1069 | } | |
1070 | } | |
1071 | ||
1072 | /* first, try to make some room in the middle buffer */ | |
5f39d397 CM |
1073 | if (left) { |
1074 | orig_slot += btrfs_header_nritems(left); | |
bce4eae9 | 1075 | wret = push_node_left(trans, root, left, mid, 1); |
79f95c82 CM |
1076 | if (wret < 0) |
1077 | ret = wret; | |
5f39d397 | 1078 | if (btrfs_header_nritems(mid) < 2) |
54aa1f4d | 1079 | err_on_enospc = 1; |
bb803951 | 1080 | } |
79f95c82 CM |
1081 | |
1082 | /* | |
1083 | * then try to empty the right most buffer into the middle | |
1084 | */ | |
5f39d397 | 1085 | if (right) { |
971a1f66 | 1086 | wret = push_node_left(trans, root, mid, right, 1); |
54aa1f4d | 1087 | if (wret < 0 && wret != -ENOSPC) |
79f95c82 | 1088 | ret = wret; |
5f39d397 | 1089 | if (btrfs_header_nritems(right) == 0) { |
db94535d CM |
1090 | u64 bytenr = right->start; |
1091 | u32 blocksize = right->len; | |
1092 | ||
5f39d397 | 1093 | clean_tree_block(trans, root, right); |
925baedd | 1094 | btrfs_tree_unlock(right); |
5f39d397 | 1095 | free_extent_buffer(right); |
bb803951 | 1096 | right = NULL; |
e089f05c CM |
1097 | wret = del_ptr(trans, root, path, level + 1, pslot + |
1098 | 1); | |
bb803951 CM |
1099 | if (wret) |
1100 | ret = wret; | |
86b9f2ec YZ |
1101 | wret = btrfs_free_tree_block(trans, root, |
1102 | bytenr, blocksize, 0, | |
1103 | root->root_key.objectid, | |
1104 | level); | |
bb803951 CM |
1105 | if (wret) |
1106 | ret = wret; | |
1107 | } else { | |
5f39d397 CM |
1108 | struct btrfs_disk_key right_key; |
1109 | btrfs_node_key(right, &right_key, 0); | |
1110 | btrfs_set_node_key(parent, &right_key, pslot + 1); | |
1111 | btrfs_mark_buffer_dirty(parent); | |
bb803951 CM |
1112 | } |
1113 | } | |
5f39d397 | 1114 | if (btrfs_header_nritems(mid) == 1) { |
79f95c82 CM |
1115 | /* |
1116 | * we're not allowed to leave a node with one item in the | |
1117 | * tree during a delete. A deletion from lower in the tree | |
1118 | * could try to delete the only pointer in this node. | |
1119 | * So, pull some keys from the left. | |
1120 | * There has to be a left pointer at this point because | |
1121 | * otherwise we would have pulled some pointers from the | |
1122 | * right | |
1123 | */ | |
5f39d397 CM |
1124 | BUG_ON(!left); |
1125 | wret = balance_node_right(trans, root, mid, left); | |
54aa1f4d | 1126 | if (wret < 0) { |
79f95c82 | 1127 | ret = wret; |
54aa1f4d CM |
1128 | goto enospc; |
1129 | } | |
bce4eae9 CM |
1130 | if (wret == 1) { |
1131 | wret = push_node_left(trans, root, left, mid, 1); | |
1132 | if (wret < 0) | |
1133 | ret = wret; | |
1134 | } | |
79f95c82 CM |
1135 | BUG_ON(wret == 1); |
1136 | } | |
5f39d397 | 1137 | if (btrfs_header_nritems(mid) == 0) { |
79f95c82 | 1138 | /* we've managed to empty the middle node, drop it */ |
db94535d CM |
1139 | u64 bytenr = mid->start; |
1140 | u32 blocksize = mid->len; | |
925baedd | 1141 | |
5f39d397 | 1142 | clean_tree_block(trans, root, mid); |
925baedd | 1143 | btrfs_tree_unlock(mid); |
5f39d397 | 1144 | free_extent_buffer(mid); |
bb803951 | 1145 | mid = NULL; |
e089f05c | 1146 | wret = del_ptr(trans, root, path, level + 1, pslot); |
bb803951 CM |
1147 | if (wret) |
1148 | ret = wret; | |
86b9f2ec YZ |
1149 | wret = btrfs_free_tree_block(trans, root, bytenr, blocksize, |
1150 | 0, root->root_key.objectid, level); | |
bb803951 CM |
1151 | if (wret) |
1152 | ret = wret; | |
79f95c82 CM |
1153 | } else { |
1154 | /* update the parent key to reflect our changes */ | |
5f39d397 CM |
1155 | struct btrfs_disk_key mid_key; |
1156 | btrfs_node_key(mid, &mid_key, 0); | |
1157 | btrfs_set_node_key(parent, &mid_key, pslot); | |
1158 | btrfs_mark_buffer_dirty(parent); | |
79f95c82 | 1159 | } |
bb803951 | 1160 | |
79f95c82 | 1161 | /* update the path */ |
5f39d397 CM |
1162 | if (left) { |
1163 | if (btrfs_header_nritems(left) > orig_slot) { | |
1164 | extent_buffer_get(left); | |
925baedd | 1165 | /* left was locked after cow */ |
5f39d397 | 1166 | path->nodes[level] = left; |
bb803951 CM |
1167 | path->slots[level + 1] -= 1; |
1168 | path->slots[level] = orig_slot; | |
925baedd CM |
1169 | if (mid) { |
1170 | btrfs_tree_unlock(mid); | |
5f39d397 | 1171 | free_extent_buffer(mid); |
925baedd | 1172 | } |
bb803951 | 1173 | } else { |
5f39d397 | 1174 | orig_slot -= btrfs_header_nritems(left); |
bb803951 CM |
1175 | path->slots[level] = orig_slot; |
1176 | } | |
1177 | } | |
79f95c82 | 1178 | /* double check we haven't messed things up */ |
123abc88 | 1179 | check_block(root, path, level); |
e20d96d6 | 1180 | if (orig_ptr != |
5f39d397 | 1181 | btrfs_node_blockptr(path->nodes[level], path->slots[level])) |
79f95c82 | 1182 | BUG(); |
54aa1f4d | 1183 | enospc: |
925baedd CM |
1184 | if (right) { |
1185 | btrfs_tree_unlock(right); | |
5f39d397 | 1186 | free_extent_buffer(right); |
925baedd CM |
1187 | } |
1188 | if (left) { | |
1189 | if (path->nodes[level] != left) | |
1190 | btrfs_tree_unlock(left); | |
5f39d397 | 1191 | free_extent_buffer(left); |
925baedd | 1192 | } |
bb803951 CM |
1193 | return ret; |
1194 | } | |
1195 | ||
d352ac68 CM |
1196 | /* Node balancing for insertion. Here we only split or push nodes around |
1197 | * when they are completely full. This is also done top down, so we | |
1198 | * have to be pessimistic. | |
1199 | */ | |
d397712b | 1200 | static noinline int push_nodes_for_insert(struct btrfs_trans_handle *trans, |
98ed5174 CM |
1201 | struct btrfs_root *root, |
1202 | struct btrfs_path *path, int level) | |
e66f709b | 1203 | { |
5f39d397 CM |
1204 | struct extent_buffer *right = NULL; |
1205 | struct extent_buffer *mid; | |
1206 | struct extent_buffer *left = NULL; | |
1207 | struct extent_buffer *parent = NULL; | |
e66f709b CM |
1208 | int ret = 0; |
1209 | int wret; | |
1210 | int pslot; | |
1211 | int orig_slot = path->slots[level]; | |
1212 | u64 orig_ptr; | |
1213 | ||
1214 | if (level == 0) | |
1215 | return 1; | |
1216 | ||
5f39d397 | 1217 | mid = path->nodes[level]; |
7bb86316 | 1218 | WARN_ON(btrfs_header_generation(mid) != trans->transid); |
e66f709b CM |
1219 | orig_ptr = btrfs_node_blockptr(mid, orig_slot); |
1220 | ||
1221 | if (level < BTRFS_MAX_LEVEL - 1) | |
5f39d397 | 1222 | parent = path->nodes[level + 1]; |
e66f709b CM |
1223 | pslot = path->slots[level + 1]; |
1224 | ||
5f39d397 | 1225 | if (!parent) |
e66f709b | 1226 | return 1; |
e66f709b | 1227 | |
5f39d397 | 1228 | left = read_node_slot(root, parent, pslot - 1); |
e66f709b CM |
1229 | |
1230 | /* first, try to make some room in the middle buffer */ | |
5f39d397 | 1231 | if (left) { |
e66f709b | 1232 | u32 left_nr; |
925baedd CM |
1233 | |
1234 | btrfs_tree_lock(left); | |
b4ce94de CM |
1235 | btrfs_set_lock_blocking(left); |
1236 | ||
5f39d397 | 1237 | left_nr = btrfs_header_nritems(left); |
33ade1f8 CM |
1238 | if (left_nr >= BTRFS_NODEPTRS_PER_BLOCK(root) - 1) { |
1239 | wret = 1; | |
1240 | } else { | |
5f39d397 | 1241 | ret = btrfs_cow_block(trans, root, left, parent, |
9fa8cfe7 | 1242 | pslot - 1, &left); |
54aa1f4d CM |
1243 | if (ret) |
1244 | wret = 1; | |
1245 | else { | |
54aa1f4d | 1246 | wret = push_node_left(trans, root, |
971a1f66 | 1247 | left, mid, 0); |
54aa1f4d | 1248 | } |
33ade1f8 | 1249 | } |
e66f709b CM |
1250 | if (wret < 0) |
1251 | ret = wret; | |
1252 | if (wret == 0) { | |
5f39d397 | 1253 | struct btrfs_disk_key disk_key; |
e66f709b | 1254 | orig_slot += left_nr; |
5f39d397 CM |
1255 | btrfs_node_key(mid, &disk_key, 0); |
1256 | btrfs_set_node_key(parent, &disk_key, pslot); | |
1257 | btrfs_mark_buffer_dirty(parent); | |
1258 | if (btrfs_header_nritems(left) > orig_slot) { | |
1259 | path->nodes[level] = left; | |
e66f709b CM |
1260 | path->slots[level + 1] -= 1; |
1261 | path->slots[level] = orig_slot; | |
925baedd | 1262 | btrfs_tree_unlock(mid); |
5f39d397 | 1263 | free_extent_buffer(mid); |
e66f709b CM |
1264 | } else { |
1265 | orig_slot -= | |
5f39d397 | 1266 | btrfs_header_nritems(left); |
e66f709b | 1267 | path->slots[level] = orig_slot; |
925baedd | 1268 | btrfs_tree_unlock(left); |
5f39d397 | 1269 | free_extent_buffer(left); |
e66f709b | 1270 | } |
e66f709b CM |
1271 | return 0; |
1272 | } | |
925baedd | 1273 | btrfs_tree_unlock(left); |
5f39d397 | 1274 | free_extent_buffer(left); |
e66f709b | 1275 | } |
925baedd | 1276 | right = read_node_slot(root, parent, pslot + 1); |
e66f709b CM |
1277 | |
1278 | /* | |
1279 | * then try to empty the right most buffer into the middle | |
1280 | */ | |
5f39d397 | 1281 | if (right) { |
33ade1f8 | 1282 | u32 right_nr; |
b4ce94de | 1283 | |
925baedd | 1284 | btrfs_tree_lock(right); |
b4ce94de CM |
1285 | btrfs_set_lock_blocking(right); |
1286 | ||
5f39d397 | 1287 | right_nr = btrfs_header_nritems(right); |
33ade1f8 CM |
1288 | if (right_nr >= BTRFS_NODEPTRS_PER_BLOCK(root) - 1) { |
1289 | wret = 1; | |
1290 | } else { | |
5f39d397 CM |
1291 | ret = btrfs_cow_block(trans, root, right, |
1292 | parent, pslot + 1, | |
9fa8cfe7 | 1293 | &right); |
54aa1f4d CM |
1294 | if (ret) |
1295 | wret = 1; | |
1296 | else { | |
54aa1f4d | 1297 | wret = balance_node_right(trans, root, |
5f39d397 | 1298 | right, mid); |
54aa1f4d | 1299 | } |
33ade1f8 | 1300 | } |
e66f709b CM |
1301 | if (wret < 0) |
1302 | ret = wret; | |
1303 | if (wret == 0) { | |
5f39d397 CM |
1304 | struct btrfs_disk_key disk_key; |
1305 | ||
1306 | btrfs_node_key(right, &disk_key, 0); | |
1307 | btrfs_set_node_key(parent, &disk_key, pslot + 1); | |
1308 | btrfs_mark_buffer_dirty(parent); | |
1309 | ||
1310 | if (btrfs_header_nritems(mid) <= orig_slot) { | |
1311 | path->nodes[level] = right; | |
e66f709b CM |
1312 | path->slots[level + 1] += 1; |
1313 | path->slots[level] = orig_slot - | |
5f39d397 | 1314 | btrfs_header_nritems(mid); |
925baedd | 1315 | btrfs_tree_unlock(mid); |
5f39d397 | 1316 | free_extent_buffer(mid); |
e66f709b | 1317 | } else { |
925baedd | 1318 | btrfs_tree_unlock(right); |
5f39d397 | 1319 | free_extent_buffer(right); |
e66f709b | 1320 | } |
e66f709b CM |
1321 | return 0; |
1322 | } | |
925baedd | 1323 | btrfs_tree_unlock(right); |
5f39d397 | 1324 | free_extent_buffer(right); |
e66f709b | 1325 | } |
e66f709b CM |
1326 | return 1; |
1327 | } | |
1328 | ||
3c69faec | 1329 | /* |
d352ac68 CM |
1330 | * readahead one full node of leaves, finding things that are close |
1331 | * to the block in 'slot', and triggering ra on them. | |
3c69faec | 1332 | */ |
c8c42864 CM |
1333 | static void reada_for_search(struct btrfs_root *root, |
1334 | struct btrfs_path *path, | |
1335 | int level, int slot, u64 objectid) | |
3c69faec | 1336 | { |
5f39d397 | 1337 | struct extent_buffer *node; |
01f46658 | 1338 | struct btrfs_disk_key disk_key; |
3c69faec | 1339 | u32 nritems; |
3c69faec | 1340 | u64 search; |
a7175319 | 1341 | u64 target; |
6b80053d | 1342 | u64 nread = 0; |
3c69faec | 1343 | int direction = path->reada; |
5f39d397 | 1344 | struct extent_buffer *eb; |
6b80053d CM |
1345 | u32 nr; |
1346 | u32 blocksize; | |
1347 | u32 nscan = 0; | |
db94535d | 1348 | |
a6b6e75e | 1349 | if (level != 1) |
6702ed49 CM |
1350 | return; |
1351 | ||
1352 | if (!path->nodes[level]) | |
3c69faec CM |
1353 | return; |
1354 | ||
5f39d397 | 1355 | node = path->nodes[level]; |
925baedd | 1356 | |
3c69faec | 1357 | search = btrfs_node_blockptr(node, slot); |
6b80053d CM |
1358 | blocksize = btrfs_level_size(root, level - 1); |
1359 | eb = btrfs_find_tree_block(root, search, blocksize); | |
5f39d397 CM |
1360 | if (eb) { |
1361 | free_extent_buffer(eb); | |
3c69faec CM |
1362 | return; |
1363 | } | |
1364 | ||
a7175319 | 1365 | target = search; |
6b80053d | 1366 | |
5f39d397 | 1367 | nritems = btrfs_header_nritems(node); |
6b80053d | 1368 | nr = slot; |
d397712b | 1369 | while (1) { |
6b80053d CM |
1370 | if (direction < 0) { |
1371 | if (nr == 0) | |
1372 | break; | |
1373 | nr--; | |
1374 | } else if (direction > 0) { | |
1375 | nr++; | |
1376 | if (nr >= nritems) | |
1377 | break; | |
3c69faec | 1378 | } |
01f46658 CM |
1379 | if (path->reada < 0 && objectid) { |
1380 | btrfs_node_key(node, &disk_key, nr); | |
1381 | if (btrfs_disk_key_objectid(&disk_key) != objectid) | |
1382 | break; | |
1383 | } | |
6b80053d | 1384 | search = btrfs_node_blockptr(node, nr); |
a7175319 CM |
1385 | if ((search <= target && target - search <= 65536) || |
1386 | (search > target && search - target <= 65536)) { | |
ca7a79ad CM |
1387 | readahead_tree_block(root, search, blocksize, |
1388 | btrfs_node_ptr_generation(node, nr)); | |
6b80053d CM |
1389 | nread += blocksize; |
1390 | } | |
1391 | nscan++; | |
a7175319 | 1392 | if ((nread > 65536 || nscan > 32)) |
6b80053d | 1393 | break; |
3c69faec CM |
1394 | } |
1395 | } | |
925baedd | 1396 | |
b4ce94de CM |
1397 | /* |
1398 | * returns -EAGAIN if it had to drop the path, or zero if everything was in | |
1399 | * cache | |
1400 | */ | |
1401 | static noinline int reada_for_balance(struct btrfs_root *root, | |
1402 | struct btrfs_path *path, int level) | |
1403 | { | |
1404 | int slot; | |
1405 | int nritems; | |
1406 | struct extent_buffer *parent; | |
1407 | struct extent_buffer *eb; | |
1408 | u64 gen; | |
1409 | u64 block1 = 0; | |
1410 | u64 block2 = 0; | |
1411 | int ret = 0; | |
1412 | int blocksize; | |
1413 | ||
8c594ea8 | 1414 | parent = path->nodes[level + 1]; |
b4ce94de CM |
1415 | if (!parent) |
1416 | return 0; | |
1417 | ||
1418 | nritems = btrfs_header_nritems(parent); | |
8c594ea8 | 1419 | slot = path->slots[level + 1]; |
b4ce94de CM |
1420 | blocksize = btrfs_level_size(root, level); |
1421 | ||
1422 | if (slot > 0) { | |
1423 | block1 = btrfs_node_blockptr(parent, slot - 1); | |
1424 | gen = btrfs_node_ptr_generation(parent, slot - 1); | |
1425 | eb = btrfs_find_tree_block(root, block1, blocksize); | |
1426 | if (eb && btrfs_buffer_uptodate(eb, gen)) | |
1427 | block1 = 0; | |
1428 | free_extent_buffer(eb); | |
1429 | } | |
8c594ea8 | 1430 | if (slot + 1 < nritems) { |
b4ce94de CM |
1431 | block2 = btrfs_node_blockptr(parent, slot + 1); |
1432 | gen = btrfs_node_ptr_generation(parent, slot + 1); | |
1433 | eb = btrfs_find_tree_block(root, block2, blocksize); | |
1434 | if (eb && btrfs_buffer_uptodate(eb, gen)) | |
1435 | block2 = 0; | |
1436 | free_extent_buffer(eb); | |
1437 | } | |
1438 | if (block1 || block2) { | |
1439 | ret = -EAGAIN; | |
8c594ea8 CM |
1440 | |
1441 | /* release the whole path */ | |
b4ce94de | 1442 | btrfs_release_path(root, path); |
8c594ea8 CM |
1443 | |
1444 | /* read the blocks */ | |
b4ce94de CM |
1445 | if (block1) |
1446 | readahead_tree_block(root, block1, blocksize, 0); | |
1447 | if (block2) | |
1448 | readahead_tree_block(root, block2, blocksize, 0); | |
1449 | ||
1450 | if (block1) { | |
1451 | eb = read_tree_block(root, block1, blocksize, 0); | |
1452 | free_extent_buffer(eb); | |
1453 | } | |
8c594ea8 | 1454 | if (block2) { |
b4ce94de CM |
1455 | eb = read_tree_block(root, block2, blocksize, 0); |
1456 | free_extent_buffer(eb); | |
1457 | } | |
1458 | } | |
1459 | return ret; | |
1460 | } | |
1461 | ||
1462 | ||
d352ac68 | 1463 | /* |
d397712b CM |
1464 | * when we walk down the tree, it is usually safe to unlock the higher layers |
1465 | * in the tree. The exceptions are when our path goes through slot 0, because | |
1466 | * operations on the tree might require changing key pointers higher up in the | |
1467 | * tree. | |
d352ac68 | 1468 | * |
d397712b CM |
1469 | * callers might also have set path->keep_locks, which tells this code to keep |
1470 | * the lock if the path points to the last slot in the block. This is part of | |
1471 | * walking through the tree, and selecting the next slot in the higher block. | |
d352ac68 | 1472 | * |
d397712b CM |
1473 | * lowest_unlock sets the lowest level in the tree we're allowed to unlock. so |
1474 | * if lowest_unlock is 1, level 0 won't be unlocked | |
d352ac68 | 1475 | */ |
e02119d5 CM |
1476 | static noinline void unlock_up(struct btrfs_path *path, int level, |
1477 | int lowest_unlock) | |
925baedd CM |
1478 | { |
1479 | int i; | |
1480 | int skip_level = level; | |
051e1b9f | 1481 | int no_skips = 0; |
925baedd CM |
1482 | struct extent_buffer *t; |
1483 | ||
1484 | for (i = level; i < BTRFS_MAX_LEVEL; i++) { | |
1485 | if (!path->nodes[i]) | |
1486 | break; | |
1487 | if (!path->locks[i]) | |
1488 | break; | |
051e1b9f | 1489 | if (!no_skips && path->slots[i] == 0) { |
925baedd CM |
1490 | skip_level = i + 1; |
1491 | continue; | |
1492 | } | |
051e1b9f | 1493 | if (!no_skips && path->keep_locks) { |
925baedd CM |
1494 | u32 nritems; |
1495 | t = path->nodes[i]; | |
1496 | nritems = btrfs_header_nritems(t); | |
051e1b9f | 1497 | if (nritems < 1 || path->slots[i] >= nritems - 1) { |
925baedd CM |
1498 | skip_level = i + 1; |
1499 | continue; | |
1500 | } | |
1501 | } | |
051e1b9f CM |
1502 | if (skip_level < i && i >= lowest_unlock) |
1503 | no_skips = 1; | |
1504 | ||
925baedd CM |
1505 | t = path->nodes[i]; |
1506 | if (i >= lowest_unlock && i > skip_level && path->locks[i]) { | |
1507 | btrfs_tree_unlock(t); | |
1508 | path->locks[i] = 0; | |
1509 | } | |
1510 | } | |
1511 | } | |
1512 | ||
b4ce94de CM |
1513 | /* |
1514 | * This releases any locks held in the path starting at level and | |
1515 | * going all the way up to the root. | |
1516 | * | |
1517 | * btrfs_search_slot will keep the lock held on higher nodes in a few | |
1518 | * corner cases, such as COW of the block at slot zero in the node. This | |
1519 | * ignores those rules, and it should only be called when there are no | |
1520 | * more updates to be done higher up in the tree. | |
1521 | */ | |
1522 | noinline void btrfs_unlock_up_safe(struct btrfs_path *path, int level) | |
1523 | { | |
1524 | int i; | |
1525 | ||
5d4f98a2 | 1526 | if (path->keep_locks) |
b4ce94de CM |
1527 | return; |
1528 | ||
1529 | for (i = level; i < BTRFS_MAX_LEVEL; i++) { | |
1530 | if (!path->nodes[i]) | |
12f4dacc | 1531 | continue; |
b4ce94de | 1532 | if (!path->locks[i]) |
12f4dacc | 1533 | continue; |
b4ce94de CM |
1534 | btrfs_tree_unlock(path->nodes[i]); |
1535 | path->locks[i] = 0; | |
1536 | } | |
1537 | } | |
1538 | ||
c8c42864 CM |
1539 | /* |
1540 | * helper function for btrfs_search_slot. The goal is to find a block | |
1541 | * in cache without setting the path to blocking. If we find the block | |
1542 | * we return zero and the path is unchanged. | |
1543 | * | |
1544 | * If we can't find the block, we set the path blocking and do some | |
1545 | * reada. -EAGAIN is returned and the search must be repeated. | |
1546 | */ | |
1547 | static int | |
1548 | read_block_for_search(struct btrfs_trans_handle *trans, | |
1549 | struct btrfs_root *root, struct btrfs_path *p, | |
1550 | struct extent_buffer **eb_ret, int level, int slot, | |
1551 | struct btrfs_key *key) | |
1552 | { | |
1553 | u64 blocknr; | |
1554 | u64 gen; | |
1555 | u32 blocksize; | |
1556 | struct extent_buffer *b = *eb_ret; | |
1557 | struct extent_buffer *tmp; | |
76a05b35 | 1558 | int ret; |
c8c42864 CM |
1559 | |
1560 | blocknr = btrfs_node_blockptr(b, slot); | |
1561 | gen = btrfs_node_ptr_generation(b, slot); | |
1562 | blocksize = btrfs_level_size(root, level - 1); | |
1563 | ||
1564 | tmp = btrfs_find_tree_block(root, blocknr, blocksize); | |
1565 | if (tmp && btrfs_buffer_uptodate(tmp, gen)) { | |
76a05b35 CM |
1566 | /* |
1567 | * we found an up to date block without sleeping, return | |
1568 | * right away | |
1569 | */ | |
c8c42864 CM |
1570 | *eb_ret = tmp; |
1571 | return 0; | |
1572 | } | |
1573 | ||
1574 | /* | |
1575 | * reduce lock contention at high levels | |
1576 | * of the btree by dropping locks before | |
76a05b35 CM |
1577 | * we read. Don't release the lock on the current |
1578 | * level because we need to walk this node to figure | |
1579 | * out which blocks to read. | |
c8c42864 | 1580 | */ |
8c594ea8 CM |
1581 | btrfs_unlock_up_safe(p, level + 1); |
1582 | btrfs_set_path_blocking(p); | |
1583 | ||
c8c42864 CM |
1584 | if (tmp) |
1585 | free_extent_buffer(tmp); | |
1586 | if (p->reada) | |
1587 | reada_for_search(root, p, level, slot, key->objectid); | |
1588 | ||
8c594ea8 | 1589 | btrfs_release_path(NULL, p); |
76a05b35 CM |
1590 | |
1591 | ret = -EAGAIN; | |
c8c42864 | 1592 | tmp = read_tree_block(root, blocknr, blocksize, gen); |
76a05b35 CM |
1593 | if (tmp) { |
1594 | /* | |
1595 | * If the read above didn't mark this buffer up to date, | |
1596 | * it will never end up being up to date. Set ret to EIO now | |
1597 | * and give up so that our caller doesn't loop forever | |
1598 | * on our EAGAINs. | |
1599 | */ | |
1600 | if (!btrfs_buffer_uptodate(tmp, 0)) | |
1601 | ret = -EIO; | |
c8c42864 | 1602 | free_extent_buffer(tmp); |
76a05b35 CM |
1603 | } |
1604 | return ret; | |
c8c42864 CM |
1605 | } |
1606 | ||
1607 | /* | |
1608 | * helper function for btrfs_search_slot. This does all of the checks | |
1609 | * for node-level blocks and does any balancing required based on | |
1610 | * the ins_len. | |
1611 | * | |
1612 | * If no extra work was required, zero is returned. If we had to | |
1613 | * drop the path, -EAGAIN is returned and btrfs_search_slot must | |
1614 | * start over | |
1615 | */ | |
1616 | static int | |
1617 | setup_nodes_for_search(struct btrfs_trans_handle *trans, | |
1618 | struct btrfs_root *root, struct btrfs_path *p, | |
1619 | struct extent_buffer *b, int level, int ins_len) | |
1620 | { | |
1621 | int ret; | |
1622 | if ((p->search_for_split || ins_len > 0) && btrfs_header_nritems(b) >= | |
1623 | BTRFS_NODEPTRS_PER_BLOCK(root) - 3) { | |
1624 | int sret; | |
1625 | ||
1626 | sret = reada_for_balance(root, p, level); | |
1627 | if (sret) | |
1628 | goto again; | |
1629 | ||
1630 | btrfs_set_path_blocking(p); | |
1631 | sret = split_node(trans, root, p, level); | |
1632 | btrfs_clear_path_blocking(p, NULL); | |
1633 | ||
1634 | BUG_ON(sret > 0); | |
1635 | if (sret) { | |
1636 | ret = sret; | |
1637 | goto done; | |
1638 | } | |
1639 | b = p->nodes[level]; | |
1640 | } else if (ins_len < 0 && btrfs_header_nritems(b) < | |
cfbb9308 | 1641 | BTRFS_NODEPTRS_PER_BLOCK(root) / 2) { |
c8c42864 CM |
1642 | int sret; |
1643 | ||
1644 | sret = reada_for_balance(root, p, level); | |
1645 | if (sret) | |
1646 | goto again; | |
1647 | ||
1648 | btrfs_set_path_blocking(p); | |
1649 | sret = balance_level(trans, root, p, level); | |
1650 | btrfs_clear_path_blocking(p, NULL); | |
1651 | ||
1652 | if (sret) { | |
1653 | ret = sret; | |
1654 | goto done; | |
1655 | } | |
1656 | b = p->nodes[level]; | |
1657 | if (!b) { | |
1658 | btrfs_release_path(NULL, p); | |
1659 | goto again; | |
1660 | } | |
1661 | BUG_ON(btrfs_header_nritems(b) == 1); | |
1662 | } | |
1663 | return 0; | |
1664 | ||
1665 | again: | |
1666 | ret = -EAGAIN; | |
1667 | done: | |
1668 | return ret; | |
1669 | } | |
1670 | ||
74123bd7 CM |
1671 | /* |
1672 | * look for key in the tree. path is filled in with nodes along the way | |
1673 | * if key is found, we return zero and you can find the item in the leaf | |
1674 | * level of the path (level 0) | |
1675 | * | |
1676 | * If the key isn't found, the path points to the slot where it should | |
aa5d6bed CM |
1677 | * be inserted, and 1 is returned. If there are other errors during the |
1678 | * search a negative error number is returned. | |
97571fd0 CM |
1679 | * |
1680 | * if ins_len > 0, nodes and leaves will be split as we walk down the | |
1681 | * tree. if ins_len < 0, nodes will be merged as we walk down the tree (if | |
1682 | * possible) | |
74123bd7 | 1683 | */ |
e089f05c CM |
1684 | int btrfs_search_slot(struct btrfs_trans_handle *trans, struct btrfs_root |
1685 | *root, struct btrfs_key *key, struct btrfs_path *p, int | |
1686 | ins_len, int cow) | |
be0e5c09 | 1687 | { |
5f39d397 | 1688 | struct extent_buffer *b; |
be0e5c09 CM |
1689 | int slot; |
1690 | int ret; | |
33c66f43 | 1691 | int err; |
be0e5c09 | 1692 | int level; |
925baedd | 1693 | int lowest_unlock = 1; |
9f3a7427 CM |
1694 | u8 lowest_level = 0; |
1695 | ||
6702ed49 | 1696 | lowest_level = p->lowest_level; |
323ac95b | 1697 | WARN_ON(lowest_level && ins_len > 0); |
22b0ebda | 1698 | WARN_ON(p->nodes[0] != NULL); |
25179201 | 1699 | |
925baedd CM |
1700 | if (ins_len < 0) |
1701 | lowest_unlock = 2; | |
65b51a00 | 1702 | |
bb803951 | 1703 | again: |
5d4f98a2 YZ |
1704 | if (p->search_commit_root) { |
1705 | b = root->commit_root; | |
1706 | extent_buffer_get(b); | |
1707 | if (!p->skip_locking) | |
1708 | btrfs_tree_lock(b); | |
1709 | } else { | |
1710 | if (p->skip_locking) | |
1711 | b = btrfs_root_node(root); | |
1712 | else | |
1713 | b = btrfs_lock_root_node(root); | |
1714 | } | |
925baedd | 1715 | |
eb60ceac | 1716 | while (b) { |
5f39d397 | 1717 | level = btrfs_header_level(b); |
65b51a00 CM |
1718 | |
1719 | /* | |
1720 | * setup the path here so we can release it under lock | |
1721 | * contention with the cow code | |
1722 | */ | |
1723 | p->nodes[level] = b; | |
1724 | if (!p->skip_locking) | |
1725 | p->locks[level] = 1; | |
1726 | ||
02217ed2 | 1727 | if (cow) { |
c8c42864 CM |
1728 | /* |
1729 | * if we don't really need to cow this block | |
1730 | * then we don't want to set the path blocking, | |
1731 | * so we test it here | |
1732 | */ | |
5d4f98a2 | 1733 | if (!should_cow_block(trans, root, b)) |
65b51a00 | 1734 | goto cow_done; |
5d4f98a2 | 1735 | |
b4ce94de CM |
1736 | btrfs_set_path_blocking(p); |
1737 | ||
33c66f43 YZ |
1738 | err = btrfs_cow_block(trans, root, b, |
1739 | p->nodes[level + 1], | |
1740 | p->slots[level + 1], &b); | |
1741 | if (err) { | |
5f39d397 | 1742 | free_extent_buffer(b); |
33c66f43 | 1743 | ret = err; |
65b51a00 | 1744 | goto done; |
54aa1f4d | 1745 | } |
02217ed2 | 1746 | } |
65b51a00 | 1747 | cow_done: |
02217ed2 | 1748 | BUG_ON(!cow && ins_len); |
5f39d397 | 1749 | if (level != btrfs_header_level(b)) |
2c90e5d6 | 1750 | WARN_ON(1); |
5f39d397 | 1751 | level = btrfs_header_level(b); |
65b51a00 | 1752 | |
eb60ceac | 1753 | p->nodes[level] = b; |
5cd57b2c CM |
1754 | if (!p->skip_locking) |
1755 | p->locks[level] = 1; | |
65b51a00 | 1756 | |
4008c04a | 1757 | btrfs_clear_path_blocking(p, NULL); |
b4ce94de CM |
1758 | |
1759 | /* | |
1760 | * we have a lock on b and as long as we aren't changing | |
1761 | * the tree, there is no way to for the items in b to change. | |
1762 | * It is safe to drop the lock on our parent before we | |
1763 | * go through the expensive btree search on b. | |
1764 | * | |
1765 | * If cow is true, then we might be changing slot zero, | |
1766 | * which may require changing the parent. So, we can't | |
1767 | * drop the lock until after we know which slot we're | |
1768 | * operating on. | |
1769 | */ | |
1770 | if (!cow) | |
1771 | btrfs_unlock_up_safe(p, level + 1); | |
1772 | ||
123abc88 | 1773 | ret = check_block(root, p, level); |
65b51a00 CM |
1774 | if (ret) { |
1775 | ret = -1; | |
1776 | goto done; | |
1777 | } | |
925baedd | 1778 | |
5f39d397 | 1779 | ret = bin_search(b, key, level, &slot); |
b4ce94de | 1780 | |
5f39d397 | 1781 | if (level != 0) { |
33c66f43 YZ |
1782 | int dec = 0; |
1783 | if (ret && slot > 0) { | |
1784 | dec = 1; | |
be0e5c09 | 1785 | slot -= 1; |
33c66f43 | 1786 | } |
be0e5c09 | 1787 | p->slots[level] = slot; |
33c66f43 | 1788 | err = setup_nodes_for_search(trans, root, p, b, level, |
c8c42864 | 1789 | ins_len); |
33c66f43 | 1790 | if (err == -EAGAIN) |
c8c42864 | 1791 | goto again; |
33c66f43 YZ |
1792 | if (err) { |
1793 | ret = err; | |
c8c42864 | 1794 | goto done; |
33c66f43 | 1795 | } |
c8c42864 CM |
1796 | b = p->nodes[level]; |
1797 | slot = p->slots[level]; | |
b4ce94de | 1798 | |
f9efa9c7 CM |
1799 | unlock_up(p, level, lowest_unlock); |
1800 | ||
925baedd | 1801 | if (level == lowest_level) { |
33c66f43 YZ |
1802 | if (dec) |
1803 | p->slots[level]++; | |
5b21f2ed | 1804 | goto done; |
925baedd | 1805 | } |
ca7a79ad | 1806 | |
33c66f43 | 1807 | err = read_block_for_search(trans, root, p, |
c8c42864 | 1808 | &b, level, slot, key); |
33c66f43 | 1809 | if (err == -EAGAIN) |
c8c42864 | 1810 | goto again; |
33c66f43 YZ |
1811 | if (err) { |
1812 | ret = err; | |
76a05b35 | 1813 | goto done; |
33c66f43 | 1814 | } |
76a05b35 | 1815 | |
b4ce94de | 1816 | if (!p->skip_locking) { |
4008c04a | 1817 | btrfs_clear_path_blocking(p, NULL); |
33c66f43 | 1818 | err = btrfs_try_spin_lock(b); |
b4ce94de | 1819 | |
33c66f43 | 1820 | if (!err) { |
b4ce94de CM |
1821 | btrfs_set_path_blocking(p); |
1822 | btrfs_tree_lock(b); | |
4008c04a | 1823 | btrfs_clear_path_blocking(p, b); |
b4ce94de CM |
1824 | } |
1825 | } | |
be0e5c09 CM |
1826 | } else { |
1827 | p->slots[level] = slot; | |
87b29b20 YZ |
1828 | if (ins_len > 0 && |
1829 | btrfs_leaf_free_space(root, b) < ins_len) { | |
b4ce94de | 1830 | btrfs_set_path_blocking(p); |
33c66f43 YZ |
1831 | err = split_leaf(trans, root, key, |
1832 | p, ins_len, ret == 0); | |
4008c04a | 1833 | btrfs_clear_path_blocking(p, NULL); |
b4ce94de | 1834 | |
33c66f43 YZ |
1835 | BUG_ON(err > 0); |
1836 | if (err) { | |
1837 | ret = err; | |
65b51a00 CM |
1838 | goto done; |
1839 | } | |
5c680ed6 | 1840 | } |
459931ec CM |
1841 | if (!p->search_for_split) |
1842 | unlock_up(p, level, lowest_unlock); | |
65b51a00 | 1843 | goto done; |
be0e5c09 CM |
1844 | } |
1845 | } | |
65b51a00 CM |
1846 | ret = 1; |
1847 | done: | |
b4ce94de CM |
1848 | /* |
1849 | * we don't really know what they plan on doing with the path | |
1850 | * from here on, so for now just mark it as blocking | |
1851 | */ | |
b9473439 CM |
1852 | if (!p->leave_spinning) |
1853 | btrfs_set_path_blocking(p); | |
76a05b35 CM |
1854 | if (ret < 0) |
1855 | btrfs_release_path(root, p); | |
65b51a00 | 1856 | return ret; |
be0e5c09 CM |
1857 | } |
1858 | ||
74123bd7 CM |
1859 | /* |
1860 | * adjust the pointers going up the tree, starting at level | |
1861 | * making sure the right key of each node is points to 'key'. | |
1862 | * This is used after shifting pointers to the left, so it stops | |
1863 | * fixing up pointers when a given leaf/node is not in slot 0 of the | |
1864 | * higher levels | |
aa5d6bed CM |
1865 | * |
1866 | * If this fails to write a tree block, it returns -1, but continues | |
1867 | * fixing up the blocks in ram so the tree is consistent. | |
74123bd7 | 1868 | */ |
5f39d397 CM |
1869 | static int fixup_low_keys(struct btrfs_trans_handle *trans, |
1870 | struct btrfs_root *root, struct btrfs_path *path, | |
1871 | struct btrfs_disk_key *key, int level) | |
be0e5c09 CM |
1872 | { |
1873 | int i; | |
aa5d6bed | 1874 | int ret = 0; |
5f39d397 CM |
1875 | struct extent_buffer *t; |
1876 | ||
234b63a0 | 1877 | for (i = level; i < BTRFS_MAX_LEVEL; i++) { |
be0e5c09 | 1878 | int tslot = path->slots[i]; |
eb60ceac | 1879 | if (!path->nodes[i]) |
be0e5c09 | 1880 | break; |
5f39d397 CM |
1881 | t = path->nodes[i]; |
1882 | btrfs_set_node_key(t, key, tslot); | |
d6025579 | 1883 | btrfs_mark_buffer_dirty(path->nodes[i]); |
be0e5c09 CM |
1884 | if (tslot != 0) |
1885 | break; | |
1886 | } | |
aa5d6bed | 1887 | return ret; |
be0e5c09 CM |
1888 | } |
1889 | ||
31840ae1 ZY |
1890 | /* |
1891 | * update item key. | |
1892 | * | |
1893 | * This function isn't completely safe. It's the caller's responsibility | |
1894 | * that the new key won't break the order | |
1895 | */ | |
1896 | int btrfs_set_item_key_safe(struct btrfs_trans_handle *trans, | |
1897 | struct btrfs_root *root, struct btrfs_path *path, | |
1898 | struct btrfs_key *new_key) | |
1899 | { | |
1900 | struct btrfs_disk_key disk_key; | |
1901 | struct extent_buffer *eb; | |
1902 | int slot; | |
1903 | ||
1904 | eb = path->nodes[0]; | |
1905 | slot = path->slots[0]; | |
1906 | if (slot > 0) { | |
1907 | btrfs_item_key(eb, &disk_key, slot - 1); | |
1908 | if (comp_keys(&disk_key, new_key) >= 0) | |
1909 | return -1; | |
1910 | } | |
1911 | if (slot < btrfs_header_nritems(eb) - 1) { | |
1912 | btrfs_item_key(eb, &disk_key, slot + 1); | |
1913 | if (comp_keys(&disk_key, new_key) <= 0) | |
1914 | return -1; | |
1915 | } | |
1916 | ||
1917 | btrfs_cpu_key_to_disk(&disk_key, new_key); | |
1918 | btrfs_set_item_key(eb, &disk_key, slot); | |
1919 | btrfs_mark_buffer_dirty(eb); | |
1920 | if (slot == 0) | |
1921 | fixup_low_keys(trans, root, path, &disk_key, 1); | |
1922 | return 0; | |
1923 | } | |
1924 | ||
74123bd7 CM |
1925 | /* |
1926 | * try to push data from one node into the next node left in the | |
79f95c82 | 1927 | * tree. |
aa5d6bed CM |
1928 | * |
1929 | * returns 0 if some ptrs were pushed left, < 0 if there was some horrible | |
1930 | * error, and > 0 if there was no room in the left hand block. | |
74123bd7 | 1931 | */ |
98ed5174 CM |
1932 | static int push_node_left(struct btrfs_trans_handle *trans, |
1933 | struct btrfs_root *root, struct extent_buffer *dst, | |
971a1f66 | 1934 | struct extent_buffer *src, int empty) |
be0e5c09 | 1935 | { |
be0e5c09 | 1936 | int push_items = 0; |
bb803951 CM |
1937 | int src_nritems; |
1938 | int dst_nritems; | |
aa5d6bed | 1939 | int ret = 0; |
be0e5c09 | 1940 | |
5f39d397 CM |
1941 | src_nritems = btrfs_header_nritems(src); |
1942 | dst_nritems = btrfs_header_nritems(dst); | |
123abc88 | 1943 | push_items = BTRFS_NODEPTRS_PER_BLOCK(root) - dst_nritems; |
7bb86316 CM |
1944 | WARN_ON(btrfs_header_generation(src) != trans->transid); |
1945 | WARN_ON(btrfs_header_generation(dst) != trans->transid); | |
54aa1f4d | 1946 | |
bce4eae9 | 1947 | if (!empty && src_nritems <= 8) |
971a1f66 CM |
1948 | return 1; |
1949 | ||
d397712b | 1950 | if (push_items <= 0) |
be0e5c09 CM |
1951 | return 1; |
1952 | ||
bce4eae9 | 1953 | if (empty) { |
971a1f66 | 1954 | push_items = min(src_nritems, push_items); |
bce4eae9 CM |
1955 | if (push_items < src_nritems) { |
1956 | /* leave at least 8 pointers in the node if | |
1957 | * we aren't going to empty it | |
1958 | */ | |
1959 | if (src_nritems - push_items < 8) { | |
1960 | if (push_items <= 8) | |
1961 | return 1; | |
1962 | push_items -= 8; | |
1963 | } | |
1964 | } | |
1965 | } else | |
1966 | push_items = min(src_nritems - 8, push_items); | |
79f95c82 | 1967 | |
5f39d397 CM |
1968 | copy_extent_buffer(dst, src, |
1969 | btrfs_node_key_ptr_offset(dst_nritems), | |
1970 | btrfs_node_key_ptr_offset(0), | |
d397712b | 1971 | push_items * sizeof(struct btrfs_key_ptr)); |
5f39d397 | 1972 | |
bb803951 | 1973 | if (push_items < src_nritems) { |
5f39d397 CM |
1974 | memmove_extent_buffer(src, btrfs_node_key_ptr_offset(0), |
1975 | btrfs_node_key_ptr_offset(push_items), | |
1976 | (src_nritems - push_items) * | |
1977 | sizeof(struct btrfs_key_ptr)); | |
1978 | } | |
1979 | btrfs_set_header_nritems(src, src_nritems - push_items); | |
1980 | btrfs_set_header_nritems(dst, dst_nritems + push_items); | |
1981 | btrfs_mark_buffer_dirty(src); | |
1982 | btrfs_mark_buffer_dirty(dst); | |
31840ae1 | 1983 | |
79f95c82 CM |
1984 | return ret; |
1985 | } | |
1986 | ||
1987 | /* | |
1988 | * try to push data from one node into the next node right in the | |
1989 | * tree. | |
1990 | * | |
1991 | * returns 0 if some ptrs were pushed, < 0 if there was some horrible | |
1992 | * error, and > 0 if there was no room in the right hand block. | |
1993 | * | |
1994 | * this will only push up to 1/2 the contents of the left node over | |
1995 | */ | |
5f39d397 CM |
1996 | static int balance_node_right(struct btrfs_trans_handle *trans, |
1997 | struct btrfs_root *root, | |
1998 | struct extent_buffer *dst, | |
1999 | struct extent_buffer *src) | |
79f95c82 | 2000 | { |
79f95c82 CM |
2001 | int push_items = 0; |
2002 | int max_push; | |
2003 | int src_nritems; | |
2004 | int dst_nritems; | |
2005 | int ret = 0; | |
79f95c82 | 2006 | |
7bb86316 CM |
2007 | WARN_ON(btrfs_header_generation(src) != trans->transid); |
2008 | WARN_ON(btrfs_header_generation(dst) != trans->transid); | |
2009 | ||
5f39d397 CM |
2010 | src_nritems = btrfs_header_nritems(src); |
2011 | dst_nritems = btrfs_header_nritems(dst); | |
123abc88 | 2012 | push_items = BTRFS_NODEPTRS_PER_BLOCK(root) - dst_nritems; |
d397712b | 2013 | if (push_items <= 0) |
79f95c82 | 2014 | return 1; |
bce4eae9 | 2015 | |
d397712b | 2016 | if (src_nritems < 4) |
bce4eae9 | 2017 | return 1; |
79f95c82 CM |
2018 | |
2019 | max_push = src_nritems / 2 + 1; | |
2020 | /* don't try to empty the node */ | |
d397712b | 2021 | if (max_push >= src_nritems) |
79f95c82 | 2022 | return 1; |
252c38f0 | 2023 | |
79f95c82 CM |
2024 | if (max_push < push_items) |
2025 | push_items = max_push; | |
2026 | ||
5f39d397 CM |
2027 | memmove_extent_buffer(dst, btrfs_node_key_ptr_offset(push_items), |
2028 | btrfs_node_key_ptr_offset(0), | |
2029 | (dst_nritems) * | |
2030 | sizeof(struct btrfs_key_ptr)); | |
d6025579 | 2031 | |
5f39d397 CM |
2032 | copy_extent_buffer(dst, src, |
2033 | btrfs_node_key_ptr_offset(0), | |
2034 | btrfs_node_key_ptr_offset(src_nritems - push_items), | |
d397712b | 2035 | push_items * sizeof(struct btrfs_key_ptr)); |
79f95c82 | 2036 | |
5f39d397 CM |
2037 | btrfs_set_header_nritems(src, src_nritems - push_items); |
2038 | btrfs_set_header_nritems(dst, dst_nritems + push_items); | |
79f95c82 | 2039 | |
5f39d397 CM |
2040 | btrfs_mark_buffer_dirty(src); |
2041 | btrfs_mark_buffer_dirty(dst); | |
31840ae1 | 2042 | |
aa5d6bed | 2043 | return ret; |
be0e5c09 CM |
2044 | } |
2045 | ||
97571fd0 CM |
2046 | /* |
2047 | * helper function to insert a new root level in the tree. | |
2048 | * A new node is allocated, and a single item is inserted to | |
2049 | * point to the existing root | |
aa5d6bed CM |
2050 | * |
2051 | * returns zero on success or < 0 on failure. | |
97571fd0 | 2052 | */ |
d397712b | 2053 | static noinline int insert_new_root(struct btrfs_trans_handle *trans, |
5f39d397 CM |
2054 | struct btrfs_root *root, |
2055 | struct btrfs_path *path, int level) | |
5c680ed6 | 2056 | { |
7bb86316 | 2057 | u64 lower_gen; |
5f39d397 CM |
2058 | struct extent_buffer *lower; |
2059 | struct extent_buffer *c; | |
925baedd | 2060 | struct extent_buffer *old; |
5f39d397 | 2061 | struct btrfs_disk_key lower_key; |
5c680ed6 CM |
2062 | |
2063 | BUG_ON(path->nodes[level]); | |
2064 | BUG_ON(path->nodes[level-1] != root->node); | |
2065 | ||
7bb86316 CM |
2066 | lower = path->nodes[level-1]; |
2067 | if (level == 1) | |
2068 | btrfs_item_key(lower, &lower_key, 0); | |
2069 | else | |
2070 | btrfs_node_key(lower, &lower_key, 0); | |
2071 | ||
31840ae1 | 2072 | c = btrfs_alloc_free_block(trans, root, root->nodesize, 0, |
5d4f98a2 | 2073 | root->root_key.objectid, &lower_key, |
ad3d81ba | 2074 | level, root->node->start, 0); |
5f39d397 CM |
2075 | if (IS_ERR(c)) |
2076 | return PTR_ERR(c); | |
925baedd | 2077 | |
5d4f98a2 | 2078 | memset_extent_buffer(c, 0, 0, sizeof(struct btrfs_header)); |
5f39d397 CM |
2079 | btrfs_set_header_nritems(c, 1); |
2080 | btrfs_set_header_level(c, level); | |
db94535d | 2081 | btrfs_set_header_bytenr(c, c->start); |
5f39d397 | 2082 | btrfs_set_header_generation(c, trans->transid); |
5d4f98a2 | 2083 | btrfs_set_header_backref_rev(c, BTRFS_MIXED_BACKREF_REV); |
5f39d397 | 2084 | btrfs_set_header_owner(c, root->root_key.objectid); |
5f39d397 CM |
2085 | |
2086 | write_extent_buffer(c, root->fs_info->fsid, | |
2087 | (unsigned long)btrfs_header_fsid(c), | |
2088 | BTRFS_FSID_SIZE); | |
e17cade2 CM |
2089 | |
2090 | write_extent_buffer(c, root->fs_info->chunk_tree_uuid, | |
2091 | (unsigned long)btrfs_header_chunk_tree_uuid(c), | |
2092 | BTRFS_UUID_SIZE); | |
2093 | ||
5f39d397 | 2094 | btrfs_set_node_key(c, &lower_key, 0); |
db94535d | 2095 | btrfs_set_node_blockptr(c, 0, lower->start); |
7bb86316 | 2096 | lower_gen = btrfs_header_generation(lower); |
31840ae1 | 2097 | WARN_ON(lower_gen != trans->transid); |
7bb86316 CM |
2098 | |
2099 | btrfs_set_node_ptr_generation(c, 0, lower_gen); | |
d5719762 | 2100 | |
5f39d397 | 2101 | btrfs_mark_buffer_dirty(c); |
d5719762 | 2102 | |
925baedd CM |
2103 | spin_lock(&root->node_lock); |
2104 | old = root->node; | |
5f39d397 | 2105 | root->node = c; |
925baedd CM |
2106 | spin_unlock(&root->node_lock); |
2107 | ||
2108 | /* the super has an extra ref to root->node */ | |
2109 | free_extent_buffer(old); | |
2110 | ||
0b86a832 | 2111 | add_root_to_dirty_list(root); |
5f39d397 CM |
2112 | extent_buffer_get(c); |
2113 | path->nodes[level] = c; | |
925baedd | 2114 | path->locks[level] = 1; |
5c680ed6 CM |
2115 | path->slots[level] = 0; |
2116 | return 0; | |
2117 | } | |
2118 | ||
74123bd7 CM |
2119 | /* |
2120 | * worker function to insert a single pointer in a node. | |
2121 | * the node should have enough room for the pointer already | |
97571fd0 | 2122 | * |
74123bd7 CM |
2123 | * slot and level indicate where you want the key to go, and |
2124 | * blocknr is the block the key points to. | |
aa5d6bed CM |
2125 | * |
2126 | * returns zero on success and < 0 on any error | |
74123bd7 | 2127 | */ |
e089f05c CM |
2128 | static int insert_ptr(struct btrfs_trans_handle *trans, struct btrfs_root |
2129 | *root, struct btrfs_path *path, struct btrfs_disk_key | |
db94535d | 2130 | *key, u64 bytenr, int slot, int level) |
74123bd7 | 2131 | { |
5f39d397 | 2132 | struct extent_buffer *lower; |
74123bd7 | 2133 | int nritems; |
5c680ed6 CM |
2134 | |
2135 | BUG_ON(!path->nodes[level]); | |
5f39d397 CM |
2136 | lower = path->nodes[level]; |
2137 | nritems = btrfs_header_nritems(lower); | |
c293498b | 2138 | BUG_ON(slot > nritems); |
123abc88 | 2139 | if (nritems == BTRFS_NODEPTRS_PER_BLOCK(root)) |
74123bd7 CM |
2140 | BUG(); |
2141 | if (slot != nritems) { | |
5f39d397 CM |
2142 | memmove_extent_buffer(lower, |
2143 | btrfs_node_key_ptr_offset(slot + 1), | |
2144 | btrfs_node_key_ptr_offset(slot), | |
d6025579 | 2145 | (nritems - slot) * sizeof(struct btrfs_key_ptr)); |
74123bd7 | 2146 | } |
5f39d397 | 2147 | btrfs_set_node_key(lower, key, slot); |
db94535d | 2148 | btrfs_set_node_blockptr(lower, slot, bytenr); |
74493f7a CM |
2149 | WARN_ON(trans->transid == 0); |
2150 | btrfs_set_node_ptr_generation(lower, slot, trans->transid); | |
5f39d397 CM |
2151 | btrfs_set_header_nritems(lower, nritems + 1); |
2152 | btrfs_mark_buffer_dirty(lower); | |
74123bd7 CM |
2153 | return 0; |
2154 | } | |
2155 | ||
97571fd0 CM |
2156 | /* |
2157 | * split the node at the specified level in path in two. | |
2158 | * The path is corrected to point to the appropriate node after the split | |
2159 | * | |
2160 | * Before splitting this tries to make some room in the node by pushing | |
2161 | * left and right, if either one works, it returns right away. | |
aa5d6bed CM |
2162 | * |
2163 | * returns 0 on success and < 0 on failure | |
97571fd0 | 2164 | */ |
e02119d5 CM |
2165 | static noinline int split_node(struct btrfs_trans_handle *trans, |
2166 | struct btrfs_root *root, | |
2167 | struct btrfs_path *path, int level) | |
be0e5c09 | 2168 | { |
5f39d397 CM |
2169 | struct extent_buffer *c; |
2170 | struct extent_buffer *split; | |
2171 | struct btrfs_disk_key disk_key; | |
be0e5c09 | 2172 | int mid; |
5c680ed6 | 2173 | int ret; |
aa5d6bed | 2174 | int wret; |
7518a238 | 2175 | u32 c_nritems; |
eb60ceac | 2176 | |
5f39d397 | 2177 | c = path->nodes[level]; |
7bb86316 | 2178 | WARN_ON(btrfs_header_generation(c) != trans->transid); |
5f39d397 | 2179 | if (c == root->node) { |
5c680ed6 | 2180 | /* trying to split the root, lets make a new one */ |
e089f05c | 2181 | ret = insert_new_root(trans, root, path, level + 1); |
5c680ed6 CM |
2182 | if (ret) |
2183 | return ret; | |
b3612421 | 2184 | } else { |
e66f709b | 2185 | ret = push_nodes_for_insert(trans, root, path, level); |
5f39d397 CM |
2186 | c = path->nodes[level]; |
2187 | if (!ret && btrfs_header_nritems(c) < | |
c448acf0 | 2188 | BTRFS_NODEPTRS_PER_BLOCK(root) - 3) |
e66f709b | 2189 | return 0; |
54aa1f4d CM |
2190 | if (ret < 0) |
2191 | return ret; | |
be0e5c09 | 2192 | } |
e66f709b | 2193 | |
5f39d397 | 2194 | c_nritems = btrfs_header_nritems(c); |
5d4f98a2 YZ |
2195 | mid = (c_nritems + 1) / 2; |
2196 | btrfs_node_key(c, &disk_key, mid); | |
7bb86316 | 2197 | |
5d4f98a2 | 2198 | split = btrfs_alloc_free_block(trans, root, root->nodesize, 0, |
31840ae1 | 2199 | root->root_key.objectid, |
5d4f98a2 | 2200 | &disk_key, level, c->start, 0); |
5f39d397 CM |
2201 | if (IS_ERR(split)) |
2202 | return PTR_ERR(split); | |
2203 | ||
5d4f98a2 | 2204 | memset_extent_buffer(split, 0, 0, sizeof(struct btrfs_header)); |
5f39d397 | 2205 | btrfs_set_header_level(split, btrfs_header_level(c)); |
db94535d | 2206 | btrfs_set_header_bytenr(split, split->start); |
5f39d397 | 2207 | btrfs_set_header_generation(split, trans->transid); |
5d4f98a2 | 2208 | btrfs_set_header_backref_rev(split, BTRFS_MIXED_BACKREF_REV); |
5f39d397 CM |
2209 | btrfs_set_header_owner(split, root->root_key.objectid); |
2210 | write_extent_buffer(split, root->fs_info->fsid, | |
2211 | (unsigned long)btrfs_header_fsid(split), | |
2212 | BTRFS_FSID_SIZE); | |
e17cade2 CM |
2213 | write_extent_buffer(split, root->fs_info->chunk_tree_uuid, |
2214 | (unsigned long)btrfs_header_chunk_tree_uuid(split), | |
2215 | BTRFS_UUID_SIZE); | |
54aa1f4d | 2216 | |
5f39d397 CM |
2217 | |
2218 | copy_extent_buffer(split, c, | |
2219 | btrfs_node_key_ptr_offset(0), | |
2220 | btrfs_node_key_ptr_offset(mid), | |
2221 | (c_nritems - mid) * sizeof(struct btrfs_key_ptr)); | |
2222 | btrfs_set_header_nritems(split, c_nritems - mid); | |
2223 | btrfs_set_header_nritems(c, mid); | |
aa5d6bed CM |
2224 | ret = 0; |
2225 | ||
5f39d397 CM |
2226 | btrfs_mark_buffer_dirty(c); |
2227 | btrfs_mark_buffer_dirty(split); | |
2228 | ||
db94535d | 2229 | wret = insert_ptr(trans, root, path, &disk_key, split->start, |
5f39d397 | 2230 | path->slots[level + 1] + 1, |
123abc88 | 2231 | level + 1); |
aa5d6bed CM |
2232 | if (wret) |
2233 | ret = wret; | |
2234 | ||
5de08d7d | 2235 | if (path->slots[level] >= mid) { |
5c680ed6 | 2236 | path->slots[level] -= mid; |
925baedd | 2237 | btrfs_tree_unlock(c); |
5f39d397 CM |
2238 | free_extent_buffer(c); |
2239 | path->nodes[level] = split; | |
5c680ed6 CM |
2240 | path->slots[level + 1] += 1; |
2241 | } else { | |
925baedd | 2242 | btrfs_tree_unlock(split); |
5f39d397 | 2243 | free_extent_buffer(split); |
be0e5c09 | 2244 | } |
aa5d6bed | 2245 | return ret; |
be0e5c09 CM |
2246 | } |
2247 | ||
74123bd7 CM |
2248 | /* |
2249 | * how many bytes are required to store the items in a leaf. start | |
2250 | * and nr indicate which items in the leaf to check. This totals up the | |
2251 | * space used both by the item structs and the item data | |
2252 | */ | |
5f39d397 | 2253 | static int leaf_space_used(struct extent_buffer *l, int start, int nr) |
be0e5c09 CM |
2254 | { |
2255 | int data_len; | |
5f39d397 | 2256 | int nritems = btrfs_header_nritems(l); |
d4dbff95 | 2257 | int end = min(nritems, start + nr) - 1; |
be0e5c09 CM |
2258 | |
2259 | if (!nr) | |
2260 | return 0; | |
5f39d397 CM |
2261 | data_len = btrfs_item_end_nr(l, start); |
2262 | data_len = data_len - btrfs_item_offset_nr(l, end); | |
0783fcfc | 2263 | data_len += sizeof(struct btrfs_item) * nr; |
d4dbff95 | 2264 | WARN_ON(data_len < 0); |
be0e5c09 CM |
2265 | return data_len; |
2266 | } | |
2267 | ||
d4dbff95 CM |
2268 | /* |
2269 | * The space between the end of the leaf items and | |
2270 | * the start of the leaf data. IOW, how much room | |
2271 | * the leaf has left for both items and data | |
2272 | */ | |
d397712b | 2273 | noinline int btrfs_leaf_free_space(struct btrfs_root *root, |
e02119d5 | 2274 | struct extent_buffer *leaf) |
d4dbff95 | 2275 | { |
5f39d397 CM |
2276 | int nritems = btrfs_header_nritems(leaf); |
2277 | int ret; | |
2278 | ret = BTRFS_LEAF_DATA_SIZE(root) - leaf_space_used(leaf, 0, nritems); | |
2279 | if (ret < 0) { | |
d397712b CM |
2280 | printk(KERN_CRIT "leaf free space ret %d, leaf data size %lu, " |
2281 | "used %d nritems %d\n", | |
ae2f5411 | 2282 | ret, (unsigned long) BTRFS_LEAF_DATA_SIZE(root), |
5f39d397 CM |
2283 | leaf_space_used(leaf, 0, nritems), nritems); |
2284 | } | |
2285 | return ret; | |
d4dbff95 CM |
2286 | } |
2287 | ||
44871b1b CM |
2288 | static noinline int __push_leaf_right(struct btrfs_trans_handle *trans, |
2289 | struct btrfs_root *root, | |
2290 | struct btrfs_path *path, | |
2291 | int data_size, int empty, | |
2292 | struct extent_buffer *right, | |
2293 | int free_space, u32 left_nritems) | |
00ec4c51 | 2294 | { |
5f39d397 | 2295 | struct extent_buffer *left = path->nodes[0]; |
44871b1b | 2296 | struct extent_buffer *upper = path->nodes[1]; |
5f39d397 | 2297 | struct btrfs_disk_key disk_key; |
00ec4c51 | 2298 | int slot; |
34a38218 | 2299 | u32 i; |
00ec4c51 CM |
2300 | int push_space = 0; |
2301 | int push_items = 0; | |
0783fcfc | 2302 | struct btrfs_item *item; |
34a38218 | 2303 | u32 nr; |
7518a238 | 2304 | u32 right_nritems; |
5f39d397 | 2305 | u32 data_end; |
db94535d | 2306 | u32 this_item_size; |
00ec4c51 | 2307 | |
34a38218 CM |
2308 | if (empty) |
2309 | nr = 0; | |
2310 | else | |
2311 | nr = 1; | |
2312 | ||
31840ae1 | 2313 | if (path->slots[0] >= left_nritems) |
87b29b20 | 2314 | push_space += data_size; |
31840ae1 | 2315 | |
44871b1b | 2316 | slot = path->slots[1]; |
34a38218 CM |
2317 | i = left_nritems - 1; |
2318 | while (i >= nr) { | |
5f39d397 | 2319 | item = btrfs_item_nr(left, i); |
db94535d | 2320 | |
31840ae1 ZY |
2321 | if (!empty && push_items > 0) { |
2322 | if (path->slots[0] > i) | |
2323 | break; | |
2324 | if (path->slots[0] == i) { | |
2325 | int space = btrfs_leaf_free_space(root, left); | |
2326 | if (space + push_space * 2 > free_space) | |
2327 | break; | |
2328 | } | |
2329 | } | |
2330 | ||
00ec4c51 | 2331 | if (path->slots[0] == i) |
87b29b20 | 2332 | push_space += data_size; |
db94535d CM |
2333 | |
2334 | if (!left->map_token) { | |
2335 | map_extent_buffer(left, (unsigned long)item, | |
2336 | sizeof(struct btrfs_item), | |
2337 | &left->map_token, &left->kaddr, | |
2338 | &left->map_start, &left->map_len, | |
2339 | KM_USER1); | |
2340 | } | |
2341 | ||
2342 | this_item_size = btrfs_item_size(left, item); | |
2343 | if (this_item_size + sizeof(*item) + push_space > free_space) | |
00ec4c51 | 2344 | break; |
31840ae1 | 2345 | |
00ec4c51 | 2346 | push_items++; |
db94535d | 2347 | push_space += this_item_size + sizeof(*item); |
34a38218 CM |
2348 | if (i == 0) |
2349 | break; | |
2350 | i--; | |
db94535d CM |
2351 | } |
2352 | if (left->map_token) { | |
2353 | unmap_extent_buffer(left, left->map_token, KM_USER1); | |
2354 | left->map_token = NULL; | |
00ec4c51 | 2355 | } |
5f39d397 | 2356 | |
925baedd CM |
2357 | if (push_items == 0) |
2358 | goto out_unlock; | |
5f39d397 | 2359 | |
34a38218 | 2360 | if (!empty && push_items == left_nritems) |
a429e513 | 2361 | WARN_ON(1); |
5f39d397 | 2362 | |
00ec4c51 | 2363 | /* push left to right */ |
5f39d397 | 2364 | right_nritems = btrfs_header_nritems(right); |
34a38218 | 2365 | |
5f39d397 | 2366 | push_space = btrfs_item_end_nr(left, left_nritems - push_items); |
123abc88 | 2367 | push_space -= leaf_data_end(root, left); |
5f39d397 | 2368 | |
00ec4c51 | 2369 | /* make room in the right data area */ |
5f39d397 CM |
2370 | data_end = leaf_data_end(root, right); |
2371 | memmove_extent_buffer(right, | |
2372 | btrfs_leaf_data(right) + data_end - push_space, | |
2373 | btrfs_leaf_data(right) + data_end, | |
2374 | BTRFS_LEAF_DATA_SIZE(root) - data_end); | |
2375 | ||
00ec4c51 | 2376 | /* copy from the left data area */ |
5f39d397 | 2377 | copy_extent_buffer(right, left, btrfs_leaf_data(right) + |
d6025579 CM |
2378 | BTRFS_LEAF_DATA_SIZE(root) - push_space, |
2379 | btrfs_leaf_data(left) + leaf_data_end(root, left), | |
2380 | push_space); | |
5f39d397 CM |
2381 | |
2382 | memmove_extent_buffer(right, btrfs_item_nr_offset(push_items), | |
2383 | btrfs_item_nr_offset(0), | |
2384 | right_nritems * sizeof(struct btrfs_item)); | |
2385 | ||
00ec4c51 | 2386 | /* copy the items from left to right */ |
5f39d397 CM |
2387 | copy_extent_buffer(right, left, btrfs_item_nr_offset(0), |
2388 | btrfs_item_nr_offset(left_nritems - push_items), | |
2389 | push_items * sizeof(struct btrfs_item)); | |
00ec4c51 CM |
2390 | |
2391 | /* update the item pointers */ | |
7518a238 | 2392 | right_nritems += push_items; |
5f39d397 | 2393 | btrfs_set_header_nritems(right, right_nritems); |
123abc88 | 2394 | push_space = BTRFS_LEAF_DATA_SIZE(root); |
7518a238 | 2395 | for (i = 0; i < right_nritems; i++) { |
5f39d397 | 2396 | item = btrfs_item_nr(right, i); |
db94535d CM |
2397 | if (!right->map_token) { |
2398 | map_extent_buffer(right, (unsigned long)item, | |
2399 | sizeof(struct btrfs_item), | |
2400 | &right->map_token, &right->kaddr, | |
2401 | &right->map_start, &right->map_len, | |
2402 | KM_USER1); | |
2403 | } | |
2404 | push_space -= btrfs_item_size(right, item); | |
2405 | btrfs_set_item_offset(right, item, push_space); | |
2406 | } | |
2407 | ||
2408 | if (right->map_token) { | |
2409 | unmap_extent_buffer(right, right->map_token, KM_USER1); | |
2410 | right->map_token = NULL; | |
00ec4c51 | 2411 | } |
7518a238 | 2412 | left_nritems -= push_items; |
5f39d397 | 2413 | btrfs_set_header_nritems(left, left_nritems); |
00ec4c51 | 2414 | |
34a38218 CM |
2415 | if (left_nritems) |
2416 | btrfs_mark_buffer_dirty(left); | |
5f39d397 | 2417 | btrfs_mark_buffer_dirty(right); |
a429e513 | 2418 | |
5f39d397 CM |
2419 | btrfs_item_key(right, &disk_key, 0); |
2420 | btrfs_set_node_key(upper, &disk_key, slot + 1); | |
d6025579 | 2421 | btrfs_mark_buffer_dirty(upper); |
02217ed2 | 2422 | |
00ec4c51 | 2423 | /* then fixup the leaf pointer in the path */ |
7518a238 CM |
2424 | if (path->slots[0] >= left_nritems) { |
2425 | path->slots[0] -= left_nritems; | |
925baedd CM |
2426 | if (btrfs_header_nritems(path->nodes[0]) == 0) |
2427 | clean_tree_block(trans, root, path->nodes[0]); | |
2428 | btrfs_tree_unlock(path->nodes[0]); | |
5f39d397 CM |
2429 | free_extent_buffer(path->nodes[0]); |
2430 | path->nodes[0] = right; | |
00ec4c51 CM |
2431 | path->slots[1] += 1; |
2432 | } else { | |
925baedd | 2433 | btrfs_tree_unlock(right); |
5f39d397 | 2434 | free_extent_buffer(right); |
00ec4c51 CM |
2435 | } |
2436 | return 0; | |
925baedd CM |
2437 | |
2438 | out_unlock: | |
2439 | btrfs_tree_unlock(right); | |
2440 | free_extent_buffer(right); | |
2441 | return 1; | |
00ec4c51 | 2442 | } |
925baedd | 2443 | |
44871b1b CM |
2444 | /* |
2445 | * push some data in the path leaf to the right, trying to free up at | |
2446 | * least data_size bytes. returns zero if the push worked, nonzero otherwise | |
2447 | * | |
2448 | * returns 1 if the push failed because the other node didn't have enough | |
2449 | * room, 0 if everything worked out and < 0 if there were major errors. | |
2450 | */ | |
2451 | static int push_leaf_right(struct btrfs_trans_handle *trans, struct btrfs_root | |
2452 | *root, struct btrfs_path *path, int data_size, | |
2453 | int empty) | |
2454 | { | |
2455 | struct extent_buffer *left = path->nodes[0]; | |
2456 | struct extent_buffer *right; | |
2457 | struct extent_buffer *upper; | |
2458 | int slot; | |
2459 | int free_space; | |
2460 | u32 left_nritems; | |
2461 | int ret; | |
2462 | ||
2463 | if (!path->nodes[1]) | |
2464 | return 1; | |
2465 | ||
2466 | slot = path->slots[1]; | |
2467 | upper = path->nodes[1]; | |
2468 | if (slot >= btrfs_header_nritems(upper) - 1) | |
2469 | return 1; | |
2470 | ||
2471 | btrfs_assert_tree_locked(path->nodes[1]); | |
2472 | ||
2473 | right = read_node_slot(root, upper, slot + 1); | |
2474 | btrfs_tree_lock(right); | |
2475 | btrfs_set_lock_blocking(right); | |
2476 | ||
2477 | free_space = btrfs_leaf_free_space(root, right); | |
2478 | if (free_space < data_size) | |
2479 | goto out_unlock; | |
2480 | ||
2481 | /* cow and double check */ | |
2482 | ret = btrfs_cow_block(trans, root, right, upper, | |
2483 | slot + 1, &right); | |
2484 | if (ret) | |
2485 | goto out_unlock; | |
2486 | ||
2487 | free_space = btrfs_leaf_free_space(root, right); | |
2488 | if (free_space < data_size) | |
2489 | goto out_unlock; | |
2490 | ||
2491 | left_nritems = btrfs_header_nritems(left); | |
2492 | if (left_nritems == 0) | |
2493 | goto out_unlock; | |
2494 | ||
2495 | return __push_leaf_right(trans, root, path, data_size, empty, | |
2496 | right, free_space, left_nritems); | |
2497 | out_unlock: | |
2498 | btrfs_tree_unlock(right); | |
2499 | free_extent_buffer(right); | |
2500 | return 1; | |
2501 | } | |
2502 | ||
74123bd7 CM |
2503 | /* |
2504 | * push some data in the path leaf to the left, trying to free up at | |
2505 | * least data_size bytes. returns zero if the push worked, nonzero otherwise | |
2506 | */ | |
44871b1b CM |
2507 | static noinline int __push_leaf_left(struct btrfs_trans_handle *trans, |
2508 | struct btrfs_root *root, | |
2509 | struct btrfs_path *path, int data_size, | |
2510 | int empty, struct extent_buffer *left, | |
2511 | int free_space, int right_nritems) | |
be0e5c09 | 2512 | { |
5f39d397 CM |
2513 | struct btrfs_disk_key disk_key; |
2514 | struct extent_buffer *right = path->nodes[0]; | |
be0e5c09 CM |
2515 | int slot; |
2516 | int i; | |
be0e5c09 CM |
2517 | int push_space = 0; |
2518 | int push_items = 0; | |
0783fcfc | 2519 | struct btrfs_item *item; |
7518a238 | 2520 | u32 old_left_nritems; |
34a38218 | 2521 | u32 nr; |
aa5d6bed CM |
2522 | int ret = 0; |
2523 | int wret; | |
db94535d CM |
2524 | u32 this_item_size; |
2525 | u32 old_left_item_size; | |
be0e5c09 CM |
2526 | |
2527 | slot = path->slots[1]; | |
02217ed2 | 2528 | |
34a38218 CM |
2529 | if (empty) |
2530 | nr = right_nritems; | |
2531 | else | |
2532 | nr = right_nritems - 1; | |
2533 | ||
2534 | for (i = 0; i < nr; i++) { | |
5f39d397 | 2535 | item = btrfs_item_nr(right, i); |
db94535d CM |
2536 | if (!right->map_token) { |
2537 | map_extent_buffer(right, (unsigned long)item, | |
2538 | sizeof(struct btrfs_item), | |
2539 | &right->map_token, &right->kaddr, | |
2540 | &right->map_start, &right->map_len, | |
2541 | KM_USER1); | |
2542 | } | |
2543 | ||
31840ae1 ZY |
2544 | if (!empty && push_items > 0) { |
2545 | if (path->slots[0] < i) | |
2546 | break; | |
2547 | if (path->slots[0] == i) { | |
2548 | int space = btrfs_leaf_free_space(root, right); | |
2549 | if (space + push_space * 2 > free_space) | |
2550 | break; | |
2551 | } | |
2552 | } | |
2553 | ||
be0e5c09 | 2554 | if (path->slots[0] == i) |
87b29b20 | 2555 | push_space += data_size; |
db94535d CM |
2556 | |
2557 | this_item_size = btrfs_item_size(right, item); | |
2558 | if (this_item_size + sizeof(*item) + push_space > free_space) | |
be0e5c09 | 2559 | break; |
db94535d | 2560 | |
be0e5c09 | 2561 | push_items++; |
db94535d CM |
2562 | push_space += this_item_size + sizeof(*item); |
2563 | } | |
2564 | ||
2565 | if (right->map_token) { | |
2566 | unmap_extent_buffer(right, right->map_token, KM_USER1); | |
2567 | right->map_token = NULL; | |
be0e5c09 | 2568 | } |
db94535d | 2569 | |
be0e5c09 | 2570 | if (push_items == 0) { |
925baedd CM |
2571 | ret = 1; |
2572 | goto out; | |
be0e5c09 | 2573 | } |
34a38218 | 2574 | if (!empty && push_items == btrfs_header_nritems(right)) |
a429e513 | 2575 | WARN_ON(1); |
5f39d397 | 2576 | |
be0e5c09 | 2577 | /* push data from right to left */ |
5f39d397 CM |
2578 | copy_extent_buffer(left, right, |
2579 | btrfs_item_nr_offset(btrfs_header_nritems(left)), | |
2580 | btrfs_item_nr_offset(0), | |
2581 | push_items * sizeof(struct btrfs_item)); | |
2582 | ||
123abc88 | 2583 | push_space = BTRFS_LEAF_DATA_SIZE(root) - |
d397712b | 2584 | btrfs_item_offset_nr(right, push_items - 1); |
5f39d397 CM |
2585 | |
2586 | copy_extent_buffer(left, right, btrfs_leaf_data(left) + | |
d6025579 CM |
2587 | leaf_data_end(root, left) - push_space, |
2588 | btrfs_leaf_data(right) + | |
5f39d397 | 2589 | btrfs_item_offset_nr(right, push_items - 1), |
d6025579 | 2590 | push_space); |
5f39d397 | 2591 | old_left_nritems = btrfs_header_nritems(left); |
87b29b20 | 2592 | BUG_ON(old_left_nritems <= 0); |
eb60ceac | 2593 | |
db94535d | 2594 | old_left_item_size = btrfs_item_offset_nr(left, old_left_nritems - 1); |
0783fcfc | 2595 | for (i = old_left_nritems; i < old_left_nritems + push_items; i++) { |
5f39d397 | 2596 | u32 ioff; |
db94535d | 2597 | |
5f39d397 | 2598 | item = btrfs_item_nr(left, i); |
db94535d CM |
2599 | if (!left->map_token) { |
2600 | map_extent_buffer(left, (unsigned long)item, | |
2601 | sizeof(struct btrfs_item), | |
2602 | &left->map_token, &left->kaddr, | |
2603 | &left->map_start, &left->map_len, | |
2604 | KM_USER1); | |
2605 | } | |
2606 | ||
5f39d397 CM |
2607 | ioff = btrfs_item_offset(left, item); |
2608 | btrfs_set_item_offset(left, item, | |
db94535d | 2609 | ioff - (BTRFS_LEAF_DATA_SIZE(root) - old_left_item_size)); |
be0e5c09 | 2610 | } |
5f39d397 | 2611 | btrfs_set_header_nritems(left, old_left_nritems + push_items); |
db94535d CM |
2612 | if (left->map_token) { |
2613 | unmap_extent_buffer(left, left->map_token, KM_USER1); | |
2614 | left->map_token = NULL; | |
2615 | } | |
be0e5c09 CM |
2616 | |
2617 | /* fixup right node */ | |
34a38218 | 2618 | if (push_items > right_nritems) { |
d397712b CM |
2619 | printk(KERN_CRIT "push items %d nr %u\n", push_items, |
2620 | right_nritems); | |
34a38218 CM |
2621 | WARN_ON(1); |
2622 | } | |
2623 | ||
2624 | if (push_items < right_nritems) { | |
2625 | push_space = btrfs_item_offset_nr(right, push_items - 1) - | |
2626 | leaf_data_end(root, right); | |
2627 | memmove_extent_buffer(right, btrfs_leaf_data(right) + | |
2628 | BTRFS_LEAF_DATA_SIZE(root) - push_space, | |
2629 | btrfs_leaf_data(right) + | |
2630 | leaf_data_end(root, right), push_space); | |
2631 | ||
2632 | memmove_extent_buffer(right, btrfs_item_nr_offset(0), | |
5f39d397 CM |
2633 | btrfs_item_nr_offset(push_items), |
2634 | (btrfs_header_nritems(right) - push_items) * | |
2635 | sizeof(struct btrfs_item)); | |
34a38218 | 2636 | } |
eef1c494 Y |
2637 | right_nritems -= push_items; |
2638 | btrfs_set_header_nritems(right, right_nritems); | |
123abc88 | 2639 | push_space = BTRFS_LEAF_DATA_SIZE(root); |
5f39d397 CM |
2640 | for (i = 0; i < right_nritems; i++) { |
2641 | item = btrfs_item_nr(right, i); | |
db94535d CM |
2642 | |
2643 | if (!right->map_token) { | |
2644 | map_extent_buffer(right, (unsigned long)item, | |
2645 | sizeof(struct btrfs_item), | |
2646 | &right->map_token, &right->kaddr, | |
2647 | &right->map_start, &right->map_len, | |
2648 | KM_USER1); | |
2649 | } | |
2650 | ||
2651 | push_space = push_space - btrfs_item_size(right, item); | |
2652 | btrfs_set_item_offset(right, item, push_space); | |
2653 | } | |
2654 | if (right->map_token) { | |
2655 | unmap_extent_buffer(right, right->map_token, KM_USER1); | |
2656 | right->map_token = NULL; | |
be0e5c09 | 2657 | } |
eb60ceac | 2658 | |
5f39d397 | 2659 | btrfs_mark_buffer_dirty(left); |
34a38218 CM |
2660 | if (right_nritems) |
2661 | btrfs_mark_buffer_dirty(right); | |
098f59c2 | 2662 | |
5f39d397 CM |
2663 | btrfs_item_key(right, &disk_key, 0); |
2664 | wret = fixup_low_keys(trans, root, path, &disk_key, 1); | |
aa5d6bed CM |
2665 | if (wret) |
2666 | ret = wret; | |
be0e5c09 CM |
2667 | |
2668 | /* then fixup the leaf pointer in the path */ | |
2669 | if (path->slots[0] < push_items) { | |
2670 | path->slots[0] += old_left_nritems; | |
925baedd CM |
2671 | if (btrfs_header_nritems(path->nodes[0]) == 0) |
2672 | clean_tree_block(trans, root, path->nodes[0]); | |
2673 | btrfs_tree_unlock(path->nodes[0]); | |
5f39d397 CM |
2674 | free_extent_buffer(path->nodes[0]); |
2675 | path->nodes[0] = left; | |
be0e5c09 CM |
2676 | path->slots[1] -= 1; |
2677 | } else { | |
925baedd | 2678 | btrfs_tree_unlock(left); |
5f39d397 | 2679 | free_extent_buffer(left); |
be0e5c09 CM |
2680 | path->slots[0] -= push_items; |
2681 | } | |
eb60ceac | 2682 | BUG_ON(path->slots[0] < 0); |
aa5d6bed | 2683 | return ret; |
925baedd CM |
2684 | out: |
2685 | btrfs_tree_unlock(left); | |
2686 | free_extent_buffer(left); | |
2687 | return ret; | |
be0e5c09 CM |
2688 | } |
2689 | ||
44871b1b CM |
2690 | /* |
2691 | * push some data in the path leaf to the left, trying to free up at | |
2692 | * least data_size bytes. returns zero if the push worked, nonzero otherwise | |
2693 | */ | |
2694 | static int push_leaf_left(struct btrfs_trans_handle *trans, struct btrfs_root | |
2695 | *root, struct btrfs_path *path, int data_size, | |
2696 | int empty) | |
2697 | { | |
2698 | struct extent_buffer *right = path->nodes[0]; | |
2699 | struct extent_buffer *left; | |
2700 | int slot; | |
2701 | int free_space; | |
2702 | u32 right_nritems; | |
2703 | int ret = 0; | |
2704 | ||
2705 | slot = path->slots[1]; | |
2706 | if (slot == 0) | |
2707 | return 1; | |
2708 | if (!path->nodes[1]) | |
2709 | return 1; | |
2710 | ||
2711 | right_nritems = btrfs_header_nritems(right); | |
2712 | if (right_nritems == 0) | |
2713 | return 1; | |
2714 | ||
2715 | btrfs_assert_tree_locked(path->nodes[1]); | |
2716 | ||
2717 | left = read_node_slot(root, path->nodes[1], slot - 1); | |
2718 | btrfs_tree_lock(left); | |
2719 | btrfs_set_lock_blocking(left); | |
2720 | ||
2721 | free_space = btrfs_leaf_free_space(root, left); | |
2722 | if (free_space < data_size) { | |
2723 | ret = 1; | |
2724 | goto out; | |
2725 | } | |
2726 | ||
2727 | /* cow and double check */ | |
2728 | ret = btrfs_cow_block(trans, root, left, | |
2729 | path->nodes[1], slot - 1, &left); | |
2730 | if (ret) { | |
2731 | /* we hit -ENOSPC, but it isn't fatal here */ | |
2732 | ret = 1; | |
2733 | goto out; | |
2734 | } | |
2735 | ||
2736 | free_space = btrfs_leaf_free_space(root, left); | |
2737 | if (free_space < data_size) { | |
2738 | ret = 1; | |
2739 | goto out; | |
2740 | } | |
2741 | ||
2742 | return __push_leaf_left(trans, root, path, data_size, | |
2743 | empty, left, free_space, right_nritems); | |
2744 | out: | |
2745 | btrfs_tree_unlock(left); | |
2746 | free_extent_buffer(left); | |
2747 | return ret; | |
2748 | } | |
2749 | ||
2750 | /* | |
2751 | * split the path's leaf in two, making sure there is at least data_size | |
2752 | * available for the resulting leaf level of the path. | |
2753 | * | |
2754 | * returns 0 if all went well and < 0 on failure. | |
2755 | */ | |
2756 | static noinline int copy_for_split(struct btrfs_trans_handle *trans, | |
2757 | struct btrfs_root *root, | |
2758 | struct btrfs_path *path, | |
2759 | struct extent_buffer *l, | |
2760 | struct extent_buffer *right, | |
2761 | int slot, int mid, int nritems) | |
2762 | { | |
2763 | int data_copy_size; | |
2764 | int rt_data_off; | |
2765 | int i; | |
2766 | int ret = 0; | |
2767 | int wret; | |
2768 | struct btrfs_disk_key disk_key; | |
2769 | ||
2770 | nritems = nritems - mid; | |
2771 | btrfs_set_header_nritems(right, nritems); | |
2772 | data_copy_size = btrfs_item_end_nr(l, mid) - leaf_data_end(root, l); | |
2773 | ||
2774 | copy_extent_buffer(right, l, btrfs_item_nr_offset(0), | |
2775 | btrfs_item_nr_offset(mid), | |
2776 | nritems * sizeof(struct btrfs_item)); | |
2777 | ||
2778 | copy_extent_buffer(right, l, | |
2779 | btrfs_leaf_data(right) + BTRFS_LEAF_DATA_SIZE(root) - | |
2780 | data_copy_size, btrfs_leaf_data(l) + | |
2781 | leaf_data_end(root, l), data_copy_size); | |
2782 | ||
2783 | rt_data_off = BTRFS_LEAF_DATA_SIZE(root) - | |
2784 | btrfs_item_end_nr(l, mid); | |
2785 | ||
2786 | for (i = 0; i < nritems; i++) { | |
2787 | struct btrfs_item *item = btrfs_item_nr(right, i); | |
2788 | u32 ioff; | |
2789 | ||
2790 | if (!right->map_token) { | |
2791 | map_extent_buffer(right, (unsigned long)item, | |
2792 | sizeof(struct btrfs_item), | |
2793 | &right->map_token, &right->kaddr, | |
2794 | &right->map_start, &right->map_len, | |
2795 | KM_USER1); | |
2796 | } | |
2797 | ||
2798 | ioff = btrfs_item_offset(right, item); | |
2799 | btrfs_set_item_offset(right, item, ioff + rt_data_off); | |
2800 | } | |
2801 | ||
2802 | if (right->map_token) { | |
2803 | unmap_extent_buffer(right, right->map_token, KM_USER1); | |
2804 | right->map_token = NULL; | |
2805 | } | |
2806 | ||
2807 | btrfs_set_header_nritems(l, mid); | |
2808 | ret = 0; | |
2809 | btrfs_item_key(right, &disk_key, 0); | |
2810 | wret = insert_ptr(trans, root, path, &disk_key, right->start, | |
2811 | path->slots[1] + 1, 1); | |
2812 | if (wret) | |
2813 | ret = wret; | |
2814 | ||
2815 | btrfs_mark_buffer_dirty(right); | |
2816 | btrfs_mark_buffer_dirty(l); | |
2817 | BUG_ON(path->slots[0] != slot); | |
2818 | ||
44871b1b CM |
2819 | if (mid <= slot) { |
2820 | btrfs_tree_unlock(path->nodes[0]); | |
2821 | free_extent_buffer(path->nodes[0]); | |
2822 | path->nodes[0] = right; | |
2823 | path->slots[0] -= mid; | |
2824 | path->slots[1] += 1; | |
2825 | } else { | |
2826 | btrfs_tree_unlock(right); | |
2827 | free_extent_buffer(right); | |
2828 | } | |
2829 | ||
2830 | BUG_ON(path->slots[0] < 0); | |
2831 | ||
2832 | return ret; | |
2833 | } | |
2834 | ||
74123bd7 CM |
2835 | /* |
2836 | * split the path's leaf in two, making sure there is at least data_size | |
2837 | * available for the resulting leaf level of the path. | |
aa5d6bed CM |
2838 | * |
2839 | * returns 0 if all went well and < 0 on failure. | |
74123bd7 | 2840 | */ |
e02119d5 CM |
2841 | static noinline int split_leaf(struct btrfs_trans_handle *trans, |
2842 | struct btrfs_root *root, | |
2843 | struct btrfs_key *ins_key, | |
2844 | struct btrfs_path *path, int data_size, | |
2845 | int extend) | |
be0e5c09 | 2846 | { |
5d4f98a2 | 2847 | struct btrfs_disk_key disk_key; |
5f39d397 | 2848 | struct extent_buffer *l; |
7518a238 | 2849 | u32 nritems; |
eb60ceac CM |
2850 | int mid; |
2851 | int slot; | |
5f39d397 | 2852 | struct extent_buffer *right; |
d4dbff95 | 2853 | int ret = 0; |
aa5d6bed | 2854 | int wret; |
5d4f98a2 | 2855 | int split; |
cc0c5538 | 2856 | int num_doubles = 0; |
aa5d6bed | 2857 | |
a5719521 YZ |
2858 | l = path->nodes[0]; |
2859 | slot = path->slots[0]; | |
2860 | if (extend && data_size + btrfs_item_size_nr(l, slot) + | |
2861 | sizeof(struct btrfs_item) > BTRFS_LEAF_DATA_SIZE(root)) | |
2862 | return -EOVERFLOW; | |
2863 | ||
40689478 | 2864 | /* first try to make some room by pushing left and right */ |
b3612421 | 2865 | if (data_size && ins_key->type != BTRFS_DIR_ITEM_KEY) { |
34a38218 | 2866 | wret = push_leaf_right(trans, root, path, data_size, 0); |
d397712b | 2867 | if (wret < 0) |
eaee50e8 | 2868 | return wret; |
3685f791 | 2869 | if (wret) { |
34a38218 | 2870 | wret = push_leaf_left(trans, root, path, data_size, 0); |
3685f791 CM |
2871 | if (wret < 0) |
2872 | return wret; | |
2873 | } | |
2874 | l = path->nodes[0]; | |
aa5d6bed | 2875 | |
3685f791 | 2876 | /* did the pushes work? */ |
87b29b20 | 2877 | if (btrfs_leaf_free_space(root, l) >= data_size) |
3685f791 | 2878 | return 0; |
3326d1b0 | 2879 | } |
aa5d6bed | 2880 | |
5c680ed6 | 2881 | if (!path->nodes[1]) { |
e089f05c | 2882 | ret = insert_new_root(trans, root, path, 1); |
5c680ed6 CM |
2883 | if (ret) |
2884 | return ret; | |
2885 | } | |
cc0c5538 | 2886 | again: |
5d4f98a2 | 2887 | split = 1; |
cc0c5538 | 2888 | l = path->nodes[0]; |
eb60ceac | 2889 | slot = path->slots[0]; |
5f39d397 | 2890 | nritems = btrfs_header_nritems(l); |
d397712b | 2891 | mid = (nritems + 1) / 2; |
54aa1f4d | 2892 | |
5d4f98a2 YZ |
2893 | if (mid <= slot) { |
2894 | if (nritems == 1 || | |
2895 | leaf_space_used(l, mid, nritems - mid) + data_size > | |
2896 | BTRFS_LEAF_DATA_SIZE(root)) { | |
2897 | if (slot >= nritems) { | |
2898 | split = 0; | |
2899 | } else { | |
2900 | mid = slot; | |
2901 | if (mid != nritems && | |
2902 | leaf_space_used(l, mid, nritems - mid) + | |
2903 | data_size > BTRFS_LEAF_DATA_SIZE(root)) { | |
2904 | split = 2; | |
2905 | } | |
2906 | } | |
2907 | } | |
2908 | } else { | |
2909 | if (leaf_space_used(l, 0, mid) + data_size > | |
2910 | BTRFS_LEAF_DATA_SIZE(root)) { | |
2911 | if (!extend && data_size && slot == 0) { | |
2912 | split = 0; | |
2913 | } else if ((extend || !data_size) && slot == 0) { | |
2914 | mid = 1; | |
2915 | } else { | |
2916 | mid = slot; | |
2917 | if (mid != nritems && | |
2918 | leaf_space_used(l, mid, nritems - mid) + | |
2919 | data_size > BTRFS_LEAF_DATA_SIZE(root)) { | |
2920 | split = 2 ; | |
2921 | } | |
2922 | } | |
2923 | } | |
2924 | } | |
2925 | ||
2926 | if (split == 0) | |
2927 | btrfs_cpu_key_to_disk(&disk_key, ins_key); | |
2928 | else | |
2929 | btrfs_item_key(l, &disk_key, mid); | |
2930 | ||
2931 | right = btrfs_alloc_free_block(trans, root, root->leafsize, 0, | |
31840ae1 | 2932 | root->root_key.objectid, |
5d4f98a2 | 2933 | &disk_key, 0, l->start, 0); |
cea9e445 CM |
2934 | if (IS_ERR(right)) { |
2935 | BUG_ON(1); | |
5f39d397 | 2936 | return PTR_ERR(right); |
cea9e445 | 2937 | } |
5f39d397 CM |
2938 | |
2939 | memset_extent_buffer(right, 0, 0, sizeof(struct btrfs_header)); | |
db94535d | 2940 | btrfs_set_header_bytenr(right, right->start); |
5f39d397 | 2941 | btrfs_set_header_generation(right, trans->transid); |
5d4f98a2 | 2942 | btrfs_set_header_backref_rev(right, BTRFS_MIXED_BACKREF_REV); |
5f39d397 CM |
2943 | btrfs_set_header_owner(right, root->root_key.objectid); |
2944 | btrfs_set_header_level(right, 0); | |
2945 | write_extent_buffer(right, root->fs_info->fsid, | |
2946 | (unsigned long)btrfs_header_fsid(right), | |
2947 | BTRFS_FSID_SIZE); | |
e17cade2 CM |
2948 | |
2949 | write_extent_buffer(right, root->fs_info->chunk_tree_uuid, | |
2950 | (unsigned long)btrfs_header_chunk_tree_uuid(right), | |
2951 | BTRFS_UUID_SIZE); | |
44871b1b | 2952 | |
5d4f98a2 YZ |
2953 | if (split == 0) { |
2954 | if (mid <= slot) { | |
2955 | btrfs_set_header_nritems(right, 0); | |
2956 | wret = insert_ptr(trans, root, path, | |
2957 | &disk_key, right->start, | |
2958 | path->slots[1] + 1, 1); | |
2959 | if (wret) | |
2960 | ret = wret; | |
925baedd | 2961 | |
5d4f98a2 YZ |
2962 | btrfs_tree_unlock(path->nodes[0]); |
2963 | free_extent_buffer(path->nodes[0]); | |
2964 | path->nodes[0] = right; | |
2965 | path->slots[0] = 0; | |
2966 | path->slots[1] += 1; | |
2967 | } else { | |
2968 | btrfs_set_header_nritems(right, 0); | |
2969 | wret = insert_ptr(trans, root, path, | |
2970 | &disk_key, | |
2971 | right->start, | |
2972 | path->slots[1], 1); | |
2973 | if (wret) | |
2974 | ret = wret; | |
2975 | btrfs_tree_unlock(path->nodes[0]); | |
2976 | free_extent_buffer(path->nodes[0]); | |
2977 | path->nodes[0] = right; | |
2978 | path->slots[0] = 0; | |
2979 | if (path->slots[1] == 0) { | |
2980 | wret = fixup_low_keys(trans, root, | |
2981 | path, &disk_key, 1); | |
d4dbff95 CM |
2982 | if (wret) |
2983 | ret = wret; | |
5ee78ac7 | 2984 | } |
d4dbff95 | 2985 | } |
5d4f98a2 YZ |
2986 | btrfs_mark_buffer_dirty(right); |
2987 | return ret; | |
d4dbff95 | 2988 | } |
74123bd7 | 2989 | |
44871b1b | 2990 | ret = copy_for_split(trans, root, path, l, right, slot, mid, nritems); |
31840ae1 ZY |
2991 | BUG_ON(ret); |
2992 | ||
5d4f98a2 | 2993 | if (split == 2) { |
cc0c5538 CM |
2994 | BUG_ON(num_doubles != 0); |
2995 | num_doubles++; | |
2996 | goto again; | |
a429e513 | 2997 | } |
44871b1b | 2998 | |
be0e5c09 CM |
2999 | return ret; |
3000 | } | |
3001 | ||
ad48fd75 YZ |
3002 | static noinline int setup_leaf_for_split(struct btrfs_trans_handle *trans, |
3003 | struct btrfs_root *root, | |
3004 | struct btrfs_path *path, int ins_len) | |
459931ec | 3005 | { |
ad48fd75 | 3006 | struct btrfs_key key; |
459931ec | 3007 | struct extent_buffer *leaf; |
ad48fd75 YZ |
3008 | struct btrfs_file_extent_item *fi; |
3009 | u64 extent_len = 0; | |
3010 | u32 item_size; | |
3011 | int ret; | |
459931ec CM |
3012 | |
3013 | leaf = path->nodes[0]; | |
ad48fd75 YZ |
3014 | btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); |
3015 | ||
3016 | BUG_ON(key.type != BTRFS_EXTENT_DATA_KEY && | |
3017 | key.type != BTRFS_EXTENT_CSUM_KEY); | |
3018 | ||
3019 | if (btrfs_leaf_free_space(root, leaf) >= ins_len) | |
3020 | return 0; | |
459931ec CM |
3021 | |
3022 | item_size = btrfs_item_size_nr(leaf, path->slots[0]); | |
ad48fd75 YZ |
3023 | if (key.type == BTRFS_EXTENT_DATA_KEY) { |
3024 | fi = btrfs_item_ptr(leaf, path->slots[0], | |
3025 | struct btrfs_file_extent_item); | |
3026 | extent_len = btrfs_file_extent_num_bytes(leaf, fi); | |
3027 | } | |
459931ec CM |
3028 | btrfs_release_path(root, path); |
3029 | ||
459931ec | 3030 | path->keep_locks = 1; |
ad48fd75 YZ |
3031 | path->search_for_split = 1; |
3032 | ret = btrfs_search_slot(trans, root, &key, path, 0, 1); | |
459931ec | 3033 | path->search_for_split = 0; |
ad48fd75 YZ |
3034 | if (ret < 0) |
3035 | goto err; | |
459931ec | 3036 | |
ad48fd75 YZ |
3037 | ret = -EAGAIN; |
3038 | leaf = path->nodes[0]; | |
459931ec | 3039 | /* if our item isn't there or got smaller, return now */ |
ad48fd75 YZ |
3040 | if (ret > 0 || item_size != btrfs_item_size_nr(leaf, path->slots[0])) |
3041 | goto err; | |
3042 | ||
3043 | if (key.type == BTRFS_EXTENT_DATA_KEY) { | |
3044 | fi = btrfs_item_ptr(leaf, path->slots[0], | |
3045 | struct btrfs_file_extent_item); | |
3046 | if (extent_len != btrfs_file_extent_num_bytes(leaf, fi)) | |
3047 | goto err; | |
459931ec CM |
3048 | } |
3049 | ||
b9473439 | 3050 | btrfs_set_path_blocking(path); |
ad48fd75 | 3051 | ret = split_leaf(trans, root, &key, path, ins_len, 1); |
459931ec CM |
3052 | BUG_ON(ret); |
3053 | ||
ad48fd75 | 3054 | path->keep_locks = 0; |
b9473439 | 3055 | btrfs_unlock_up_safe(path, 1); |
ad48fd75 YZ |
3056 | return 0; |
3057 | err: | |
3058 | path->keep_locks = 0; | |
3059 | return ret; | |
3060 | } | |
3061 | ||
3062 | static noinline int split_item(struct btrfs_trans_handle *trans, | |
3063 | struct btrfs_root *root, | |
3064 | struct btrfs_path *path, | |
3065 | struct btrfs_key *new_key, | |
3066 | unsigned long split_offset) | |
3067 | { | |
3068 | struct extent_buffer *leaf; | |
3069 | struct btrfs_item *item; | |
3070 | struct btrfs_item *new_item; | |
3071 | int slot; | |
3072 | char *buf; | |
3073 | u32 nritems; | |
3074 | u32 item_size; | |
3075 | u32 orig_offset; | |
3076 | struct btrfs_disk_key disk_key; | |
3077 | ||
b9473439 CM |
3078 | leaf = path->nodes[0]; |
3079 | BUG_ON(btrfs_leaf_free_space(root, leaf) < sizeof(struct btrfs_item)); | |
3080 | ||
b4ce94de CM |
3081 | btrfs_set_path_blocking(path); |
3082 | ||
459931ec CM |
3083 | item = btrfs_item_nr(leaf, path->slots[0]); |
3084 | orig_offset = btrfs_item_offset(leaf, item); | |
3085 | item_size = btrfs_item_size(leaf, item); | |
3086 | ||
459931ec | 3087 | buf = kmalloc(item_size, GFP_NOFS); |
ad48fd75 YZ |
3088 | if (!buf) |
3089 | return -ENOMEM; | |
3090 | ||
459931ec CM |
3091 | read_extent_buffer(leaf, buf, btrfs_item_ptr_offset(leaf, |
3092 | path->slots[0]), item_size); | |
459931ec | 3093 | |
ad48fd75 | 3094 | slot = path->slots[0] + 1; |
459931ec | 3095 | nritems = btrfs_header_nritems(leaf); |
459931ec CM |
3096 | if (slot != nritems) { |
3097 | /* shift the items */ | |
3098 | memmove_extent_buffer(leaf, btrfs_item_nr_offset(slot + 1), | |
ad48fd75 YZ |
3099 | btrfs_item_nr_offset(slot), |
3100 | (nritems - slot) * sizeof(struct btrfs_item)); | |
459931ec CM |
3101 | } |
3102 | ||
3103 | btrfs_cpu_key_to_disk(&disk_key, new_key); | |
3104 | btrfs_set_item_key(leaf, &disk_key, slot); | |
3105 | ||
3106 | new_item = btrfs_item_nr(leaf, slot); | |
3107 | ||
3108 | btrfs_set_item_offset(leaf, new_item, orig_offset); | |
3109 | btrfs_set_item_size(leaf, new_item, item_size - split_offset); | |
3110 | ||
3111 | btrfs_set_item_offset(leaf, item, | |
3112 | orig_offset + item_size - split_offset); | |
3113 | btrfs_set_item_size(leaf, item, split_offset); | |
3114 | ||
3115 | btrfs_set_header_nritems(leaf, nritems + 1); | |
3116 | ||
3117 | /* write the data for the start of the original item */ | |
3118 | write_extent_buffer(leaf, buf, | |
3119 | btrfs_item_ptr_offset(leaf, path->slots[0]), | |
3120 | split_offset); | |
3121 | ||
3122 | /* write the data for the new item */ | |
3123 | write_extent_buffer(leaf, buf + split_offset, | |
3124 | btrfs_item_ptr_offset(leaf, slot), | |
3125 | item_size - split_offset); | |
3126 | btrfs_mark_buffer_dirty(leaf); | |
3127 | ||
ad48fd75 | 3128 | BUG_ON(btrfs_leaf_free_space(root, leaf) < 0); |
459931ec | 3129 | kfree(buf); |
ad48fd75 YZ |
3130 | return 0; |
3131 | } | |
3132 | ||
3133 | /* | |
3134 | * This function splits a single item into two items, | |
3135 | * giving 'new_key' to the new item and splitting the | |
3136 | * old one at split_offset (from the start of the item). | |
3137 | * | |
3138 | * The path may be released by this operation. After | |
3139 | * the split, the path is pointing to the old item. The | |
3140 | * new item is going to be in the same node as the old one. | |
3141 | * | |
3142 | * Note, the item being split must be smaller enough to live alone on | |
3143 | * a tree block with room for one extra struct btrfs_item | |
3144 | * | |
3145 | * This allows us to split the item in place, keeping a lock on the | |
3146 | * leaf the entire time. | |
3147 | */ | |
3148 | int btrfs_split_item(struct btrfs_trans_handle *trans, | |
3149 | struct btrfs_root *root, | |
3150 | struct btrfs_path *path, | |
3151 | struct btrfs_key *new_key, | |
3152 | unsigned long split_offset) | |
3153 | { | |
3154 | int ret; | |
3155 | ret = setup_leaf_for_split(trans, root, path, | |
3156 | sizeof(struct btrfs_item)); | |
3157 | if (ret) | |
3158 | return ret; | |
3159 | ||
3160 | ret = split_item(trans, root, path, new_key, split_offset); | |
459931ec CM |
3161 | return ret; |
3162 | } | |
3163 | ||
ad48fd75 YZ |
3164 | /* |
3165 | * This function duplicate a item, giving 'new_key' to the new item. | |
3166 | * It guarantees both items live in the same tree leaf and the new item | |
3167 | * is contiguous with the original item. | |
3168 | * | |
3169 | * This allows us to split file extent in place, keeping a lock on the | |
3170 | * leaf the entire time. | |
3171 | */ | |
3172 | int btrfs_duplicate_item(struct btrfs_trans_handle *trans, | |
3173 | struct btrfs_root *root, | |
3174 | struct btrfs_path *path, | |
3175 | struct btrfs_key *new_key) | |
3176 | { | |
3177 | struct extent_buffer *leaf; | |
3178 | int ret; | |
3179 | u32 item_size; | |
3180 | ||
3181 | leaf = path->nodes[0]; | |
3182 | item_size = btrfs_item_size_nr(leaf, path->slots[0]); | |
3183 | ret = setup_leaf_for_split(trans, root, path, | |
3184 | item_size + sizeof(struct btrfs_item)); | |
3185 | if (ret) | |
3186 | return ret; | |
3187 | ||
3188 | path->slots[0]++; | |
3189 | ret = setup_items_for_insert(trans, root, path, new_key, &item_size, | |
3190 | item_size, item_size + | |
3191 | sizeof(struct btrfs_item), 1); | |
3192 | BUG_ON(ret); | |
3193 | ||
3194 | leaf = path->nodes[0]; | |
3195 | memcpy_extent_buffer(leaf, | |
3196 | btrfs_item_ptr_offset(leaf, path->slots[0]), | |
3197 | btrfs_item_ptr_offset(leaf, path->slots[0] - 1), | |
3198 | item_size); | |
3199 | return 0; | |
3200 | } | |
3201 | ||
d352ac68 CM |
3202 | /* |
3203 | * make the item pointed to by the path smaller. new_size indicates | |
3204 | * how small to make it, and from_end tells us if we just chop bytes | |
3205 | * off the end of the item or if we shift the item to chop bytes off | |
3206 | * the front. | |
3207 | */ | |
b18c6685 CM |
3208 | int btrfs_truncate_item(struct btrfs_trans_handle *trans, |
3209 | struct btrfs_root *root, | |
3210 | struct btrfs_path *path, | |
179e29e4 | 3211 | u32 new_size, int from_end) |
b18c6685 CM |
3212 | { |
3213 | int ret = 0; | |
3214 | int slot; | |
3215 | int slot_orig; | |
5f39d397 CM |
3216 | struct extent_buffer *leaf; |
3217 | struct btrfs_item *item; | |
b18c6685 CM |
3218 | u32 nritems; |
3219 | unsigned int data_end; | |
3220 | unsigned int old_data_start; | |
3221 | unsigned int old_size; | |
3222 | unsigned int size_diff; | |
3223 | int i; | |
3224 | ||
3225 | slot_orig = path->slots[0]; | |
5f39d397 | 3226 | leaf = path->nodes[0]; |
179e29e4 CM |
3227 | slot = path->slots[0]; |
3228 | ||
3229 | old_size = btrfs_item_size_nr(leaf, slot); | |
3230 | if (old_size == new_size) | |
3231 | return 0; | |
b18c6685 | 3232 | |
5f39d397 | 3233 | nritems = btrfs_header_nritems(leaf); |
b18c6685 CM |
3234 | data_end = leaf_data_end(root, leaf); |
3235 | ||
5f39d397 | 3236 | old_data_start = btrfs_item_offset_nr(leaf, slot); |
179e29e4 | 3237 | |
b18c6685 CM |
3238 | size_diff = old_size - new_size; |
3239 | ||
3240 | BUG_ON(slot < 0); | |
3241 | BUG_ON(slot >= nritems); | |
3242 | ||
3243 | /* | |
3244 | * item0..itemN ... dataN.offset..dataN.size .. data0.size | |
3245 | */ | |
3246 | /* first correct the data pointers */ | |
3247 | for (i = slot; i < nritems; i++) { | |
5f39d397 CM |
3248 | u32 ioff; |
3249 | item = btrfs_item_nr(leaf, i); | |
db94535d CM |
3250 | |
3251 | if (!leaf->map_token) { | |
3252 | map_extent_buffer(leaf, (unsigned long)item, | |
3253 | sizeof(struct btrfs_item), | |
3254 | &leaf->map_token, &leaf->kaddr, | |
3255 | &leaf->map_start, &leaf->map_len, | |
3256 | KM_USER1); | |
3257 | } | |
3258 | ||
5f39d397 CM |
3259 | ioff = btrfs_item_offset(leaf, item); |
3260 | btrfs_set_item_offset(leaf, item, ioff + size_diff); | |
b18c6685 | 3261 | } |
db94535d CM |
3262 | |
3263 | if (leaf->map_token) { | |
3264 | unmap_extent_buffer(leaf, leaf->map_token, KM_USER1); | |
3265 | leaf->map_token = NULL; | |
3266 | } | |
3267 | ||
b18c6685 | 3268 | /* shift the data */ |
179e29e4 CM |
3269 | if (from_end) { |
3270 | memmove_extent_buffer(leaf, btrfs_leaf_data(leaf) + | |
3271 | data_end + size_diff, btrfs_leaf_data(leaf) + | |
3272 | data_end, old_data_start + new_size - data_end); | |
3273 | } else { | |
3274 | struct btrfs_disk_key disk_key; | |
3275 | u64 offset; | |
3276 | ||
3277 | btrfs_item_key(leaf, &disk_key, slot); | |
3278 | ||
3279 | if (btrfs_disk_key_type(&disk_key) == BTRFS_EXTENT_DATA_KEY) { | |
3280 | unsigned long ptr; | |
3281 | struct btrfs_file_extent_item *fi; | |
3282 | ||
3283 | fi = btrfs_item_ptr(leaf, slot, | |
3284 | struct btrfs_file_extent_item); | |
3285 | fi = (struct btrfs_file_extent_item *)( | |
3286 | (unsigned long)fi - size_diff); | |
3287 | ||
3288 | if (btrfs_file_extent_type(leaf, fi) == | |
3289 | BTRFS_FILE_EXTENT_INLINE) { | |
3290 | ptr = btrfs_item_ptr_offset(leaf, slot); | |
3291 | memmove_extent_buffer(leaf, ptr, | |
d397712b CM |
3292 | (unsigned long)fi, |
3293 | offsetof(struct btrfs_file_extent_item, | |
179e29e4 CM |
3294 | disk_bytenr)); |
3295 | } | |
3296 | } | |
3297 | ||
3298 | memmove_extent_buffer(leaf, btrfs_leaf_data(leaf) + | |
3299 | data_end + size_diff, btrfs_leaf_data(leaf) + | |
3300 | data_end, old_data_start - data_end); | |
3301 | ||
3302 | offset = btrfs_disk_key_offset(&disk_key); | |
3303 | btrfs_set_disk_key_offset(&disk_key, offset + size_diff); | |
3304 | btrfs_set_item_key(leaf, &disk_key, slot); | |
3305 | if (slot == 0) | |
3306 | fixup_low_keys(trans, root, path, &disk_key, 1); | |
3307 | } | |
5f39d397 CM |
3308 | |
3309 | item = btrfs_item_nr(leaf, slot); | |
3310 | btrfs_set_item_size(leaf, item, new_size); | |
3311 | btrfs_mark_buffer_dirty(leaf); | |
b18c6685 CM |
3312 | |
3313 | ret = 0; | |
5f39d397 CM |
3314 | if (btrfs_leaf_free_space(root, leaf) < 0) { |
3315 | btrfs_print_leaf(root, leaf); | |
b18c6685 | 3316 | BUG(); |
5f39d397 | 3317 | } |
b18c6685 CM |
3318 | return ret; |
3319 | } | |
3320 | ||
d352ac68 CM |
3321 | /* |
3322 | * make the item pointed to by the path bigger, data_size is the new size. | |
3323 | */ | |
5f39d397 CM |
3324 | int btrfs_extend_item(struct btrfs_trans_handle *trans, |
3325 | struct btrfs_root *root, struct btrfs_path *path, | |
3326 | u32 data_size) | |
6567e837 CM |
3327 | { |
3328 | int ret = 0; | |
3329 | int slot; | |
3330 | int slot_orig; | |
5f39d397 CM |
3331 | struct extent_buffer *leaf; |
3332 | struct btrfs_item *item; | |
6567e837 CM |
3333 | u32 nritems; |
3334 | unsigned int data_end; | |
3335 | unsigned int old_data; | |
3336 | unsigned int old_size; | |
3337 | int i; | |
3338 | ||
3339 | slot_orig = path->slots[0]; | |
5f39d397 | 3340 | leaf = path->nodes[0]; |
6567e837 | 3341 | |
5f39d397 | 3342 | nritems = btrfs_header_nritems(leaf); |
6567e837 CM |
3343 | data_end = leaf_data_end(root, leaf); |
3344 | ||
5f39d397 CM |
3345 | if (btrfs_leaf_free_space(root, leaf) < data_size) { |
3346 | btrfs_print_leaf(root, leaf); | |
6567e837 | 3347 | BUG(); |
5f39d397 | 3348 | } |
6567e837 | 3349 | slot = path->slots[0]; |
5f39d397 | 3350 | old_data = btrfs_item_end_nr(leaf, slot); |
6567e837 CM |
3351 | |
3352 | BUG_ON(slot < 0); | |
3326d1b0 CM |
3353 | if (slot >= nritems) { |
3354 | btrfs_print_leaf(root, leaf); | |
d397712b CM |
3355 | printk(KERN_CRIT "slot %d too large, nritems %d\n", |
3356 | slot, nritems); | |
3326d1b0 CM |
3357 | BUG_ON(1); |
3358 | } | |
6567e837 CM |
3359 | |
3360 | /* | |
3361 | * item0..itemN ... dataN.offset..dataN.size .. data0.size | |
3362 | */ | |
3363 | /* first correct the data pointers */ | |
3364 | for (i = slot; i < nritems; i++) { | |
5f39d397 CM |
3365 | u32 ioff; |
3366 | item = btrfs_item_nr(leaf, i); | |
db94535d CM |
3367 | |
3368 | if (!leaf->map_token) { | |
3369 | map_extent_buffer(leaf, (unsigned long)item, | |
3370 | sizeof(struct btrfs_item), | |
3371 | &leaf->map_token, &leaf->kaddr, | |
3372 | &leaf->map_start, &leaf->map_len, | |
3373 | KM_USER1); | |
3374 | } | |
5f39d397 CM |
3375 | ioff = btrfs_item_offset(leaf, item); |
3376 | btrfs_set_item_offset(leaf, item, ioff - data_size); | |
6567e837 | 3377 | } |
5f39d397 | 3378 | |
db94535d CM |
3379 | if (leaf->map_token) { |
3380 | unmap_extent_buffer(leaf, leaf->map_token, KM_USER1); | |
3381 | leaf->map_token = NULL; | |
3382 | } | |
3383 | ||
6567e837 | 3384 | /* shift the data */ |
5f39d397 | 3385 | memmove_extent_buffer(leaf, btrfs_leaf_data(leaf) + |
6567e837 CM |
3386 | data_end - data_size, btrfs_leaf_data(leaf) + |
3387 | data_end, old_data - data_end); | |
5f39d397 | 3388 | |
6567e837 | 3389 | data_end = old_data; |
5f39d397 CM |
3390 | old_size = btrfs_item_size_nr(leaf, slot); |
3391 | item = btrfs_item_nr(leaf, slot); | |
3392 | btrfs_set_item_size(leaf, item, old_size + data_size); | |
3393 | btrfs_mark_buffer_dirty(leaf); | |
6567e837 CM |
3394 | |
3395 | ret = 0; | |
5f39d397 CM |
3396 | if (btrfs_leaf_free_space(root, leaf) < 0) { |
3397 | btrfs_print_leaf(root, leaf); | |
6567e837 | 3398 | BUG(); |
5f39d397 | 3399 | } |
6567e837 CM |
3400 | return ret; |
3401 | } | |
3402 | ||
f3465ca4 JB |
3403 | /* |
3404 | * Given a key and some data, insert items into the tree. | |
3405 | * This does all the path init required, making room in the tree if needed. | |
3406 | * Returns the number of keys that were inserted. | |
3407 | */ | |
3408 | int btrfs_insert_some_items(struct btrfs_trans_handle *trans, | |
3409 | struct btrfs_root *root, | |
3410 | struct btrfs_path *path, | |
3411 | struct btrfs_key *cpu_key, u32 *data_size, | |
3412 | int nr) | |
3413 | { | |
3414 | struct extent_buffer *leaf; | |
3415 | struct btrfs_item *item; | |
3416 | int ret = 0; | |
3417 | int slot; | |
f3465ca4 JB |
3418 | int i; |
3419 | u32 nritems; | |
3420 | u32 total_data = 0; | |
3421 | u32 total_size = 0; | |
3422 | unsigned int data_end; | |
3423 | struct btrfs_disk_key disk_key; | |
3424 | struct btrfs_key found_key; | |
3425 | ||
87b29b20 YZ |
3426 | for (i = 0; i < nr; i++) { |
3427 | if (total_size + data_size[i] + sizeof(struct btrfs_item) > | |
3428 | BTRFS_LEAF_DATA_SIZE(root)) { | |
3429 | break; | |
3430 | nr = i; | |
3431 | } | |
f3465ca4 | 3432 | total_data += data_size[i]; |
87b29b20 YZ |
3433 | total_size += data_size[i] + sizeof(struct btrfs_item); |
3434 | } | |
3435 | BUG_ON(nr == 0); | |
f3465ca4 | 3436 | |
f3465ca4 JB |
3437 | ret = btrfs_search_slot(trans, root, cpu_key, path, total_size, 1); |
3438 | if (ret == 0) | |
3439 | return -EEXIST; | |
3440 | if (ret < 0) | |
3441 | goto out; | |
3442 | ||
f3465ca4 JB |
3443 | leaf = path->nodes[0]; |
3444 | ||
3445 | nritems = btrfs_header_nritems(leaf); | |
3446 | data_end = leaf_data_end(root, leaf); | |
3447 | ||
3448 | if (btrfs_leaf_free_space(root, leaf) < total_size) { | |
3449 | for (i = nr; i >= 0; i--) { | |
3450 | total_data -= data_size[i]; | |
3451 | total_size -= data_size[i] + sizeof(struct btrfs_item); | |
3452 | if (total_size < btrfs_leaf_free_space(root, leaf)) | |
3453 | break; | |
3454 | } | |
3455 | nr = i; | |
3456 | } | |
3457 | ||
3458 | slot = path->slots[0]; | |
3459 | BUG_ON(slot < 0); | |
3460 | ||
3461 | if (slot != nritems) { | |
3462 | unsigned int old_data = btrfs_item_end_nr(leaf, slot); | |
3463 | ||
3464 | item = btrfs_item_nr(leaf, slot); | |
3465 | btrfs_item_key_to_cpu(leaf, &found_key, slot); | |
3466 | ||
3467 | /* figure out how many keys we can insert in here */ | |
3468 | total_data = data_size[0]; | |
3469 | for (i = 1; i < nr; i++) { | |
5d4f98a2 | 3470 | if (btrfs_comp_cpu_keys(&found_key, cpu_key + i) <= 0) |
f3465ca4 JB |
3471 | break; |
3472 | total_data += data_size[i]; | |
3473 | } | |
3474 | nr = i; | |
3475 | ||
3476 | if (old_data < data_end) { | |
3477 | btrfs_print_leaf(root, leaf); | |
d397712b | 3478 | printk(KERN_CRIT "slot %d old_data %d data_end %d\n", |
f3465ca4 JB |
3479 | slot, old_data, data_end); |
3480 | BUG_ON(1); | |
3481 | } | |
3482 | /* | |
3483 | * item0..itemN ... dataN.offset..dataN.size .. data0.size | |
3484 | */ | |
3485 | /* first correct the data pointers */ | |
3486 | WARN_ON(leaf->map_token); | |
3487 | for (i = slot; i < nritems; i++) { | |
3488 | u32 ioff; | |
3489 | ||
3490 | item = btrfs_item_nr(leaf, i); | |
3491 | if (!leaf->map_token) { | |
3492 | map_extent_buffer(leaf, (unsigned long)item, | |
3493 | sizeof(struct btrfs_item), | |
3494 | &leaf->map_token, &leaf->kaddr, | |
3495 | &leaf->map_start, &leaf->map_len, | |
3496 | KM_USER1); | |
3497 | } | |
3498 | ||
3499 | ioff = btrfs_item_offset(leaf, item); | |
3500 | btrfs_set_item_offset(leaf, item, ioff - total_data); | |
3501 | } | |
3502 | if (leaf->map_token) { | |
3503 | unmap_extent_buffer(leaf, leaf->map_token, KM_USER1); | |
3504 | leaf->map_token = NULL; | |
3505 | } | |
3506 | ||
3507 | /* shift the items */ | |
3508 | memmove_extent_buffer(leaf, btrfs_item_nr_offset(slot + nr), | |
3509 | btrfs_item_nr_offset(slot), | |
3510 | (nritems - slot) * sizeof(struct btrfs_item)); | |
3511 | ||
3512 | /* shift the data */ | |
3513 | memmove_extent_buffer(leaf, btrfs_leaf_data(leaf) + | |
3514 | data_end - total_data, btrfs_leaf_data(leaf) + | |
3515 | data_end, old_data - data_end); | |
3516 | data_end = old_data; | |
3517 | } else { | |
3518 | /* | |
3519 | * this sucks but it has to be done, if we are inserting at | |
3520 | * the end of the leaf only insert 1 of the items, since we | |
3521 | * have no way of knowing whats on the next leaf and we'd have | |
3522 | * to drop our current locks to figure it out | |
3523 | */ | |
3524 | nr = 1; | |
3525 | } | |
3526 | ||
3527 | /* setup the item for the new data */ | |
3528 | for (i = 0; i < nr; i++) { | |
3529 | btrfs_cpu_key_to_disk(&disk_key, cpu_key + i); | |
3530 | btrfs_set_item_key(leaf, &disk_key, slot + i); | |
3531 | item = btrfs_item_nr(leaf, slot + i); | |
3532 | btrfs_set_item_offset(leaf, item, data_end - data_size[i]); | |
3533 | data_end -= data_size[i]; | |
3534 | btrfs_set_item_size(leaf, item, data_size[i]); | |
3535 | } | |
3536 | btrfs_set_header_nritems(leaf, nritems + nr); | |
3537 | btrfs_mark_buffer_dirty(leaf); | |
3538 | ||
3539 | ret = 0; | |
3540 | if (slot == 0) { | |
3541 | btrfs_cpu_key_to_disk(&disk_key, cpu_key); | |
3542 | ret = fixup_low_keys(trans, root, path, &disk_key, 1); | |
3543 | } | |
3544 | ||
3545 | if (btrfs_leaf_free_space(root, leaf) < 0) { | |
3546 | btrfs_print_leaf(root, leaf); | |
3547 | BUG(); | |
3548 | } | |
3549 | out: | |
3550 | if (!ret) | |
3551 | ret = nr; | |
3552 | return ret; | |
3553 | } | |
3554 | ||
74123bd7 | 3555 | /* |
44871b1b CM |
3556 | * this is a helper for btrfs_insert_empty_items, the main goal here is |
3557 | * to save stack depth by doing the bulk of the work in a function | |
3558 | * that doesn't call btrfs_search_slot | |
74123bd7 | 3559 | */ |
44871b1b CM |
3560 | static noinline_for_stack int |
3561 | setup_items_for_insert(struct btrfs_trans_handle *trans, | |
3562 | struct btrfs_root *root, struct btrfs_path *path, | |
3563 | struct btrfs_key *cpu_key, u32 *data_size, | |
3564 | u32 total_data, u32 total_size, int nr) | |
be0e5c09 | 3565 | { |
5f39d397 | 3566 | struct btrfs_item *item; |
9c58309d | 3567 | int i; |
7518a238 | 3568 | u32 nritems; |
be0e5c09 | 3569 | unsigned int data_end; |
e2fa7227 | 3570 | struct btrfs_disk_key disk_key; |
44871b1b CM |
3571 | int ret; |
3572 | struct extent_buffer *leaf; | |
3573 | int slot; | |
e2fa7227 | 3574 | |
5f39d397 | 3575 | leaf = path->nodes[0]; |
44871b1b | 3576 | slot = path->slots[0]; |
74123bd7 | 3577 | |
5f39d397 | 3578 | nritems = btrfs_header_nritems(leaf); |
123abc88 | 3579 | data_end = leaf_data_end(root, leaf); |
eb60ceac | 3580 | |
f25956cc | 3581 | if (btrfs_leaf_free_space(root, leaf) < total_size) { |
3326d1b0 | 3582 | btrfs_print_leaf(root, leaf); |
d397712b | 3583 | printk(KERN_CRIT "not enough freespace need %u have %d\n", |
9c58309d | 3584 | total_size, btrfs_leaf_free_space(root, leaf)); |
be0e5c09 | 3585 | BUG(); |
d4dbff95 | 3586 | } |
5f39d397 | 3587 | |
be0e5c09 | 3588 | if (slot != nritems) { |
5f39d397 | 3589 | unsigned int old_data = btrfs_item_end_nr(leaf, slot); |
be0e5c09 | 3590 | |
5f39d397 CM |
3591 | if (old_data < data_end) { |
3592 | btrfs_print_leaf(root, leaf); | |
d397712b | 3593 | printk(KERN_CRIT "slot %d old_data %d data_end %d\n", |
5f39d397 CM |
3594 | slot, old_data, data_end); |
3595 | BUG_ON(1); | |
3596 | } | |
be0e5c09 CM |
3597 | /* |
3598 | * item0..itemN ... dataN.offset..dataN.size .. data0.size | |
3599 | */ | |
3600 | /* first correct the data pointers */ | |
db94535d | 3601 | WARN_ON(leaf->map_token); |
0783fcfc | 3602 | for (i = slot; i < nritems; i++) { |
5f39d397 | 3603 | u32 ioff; |
db94535d | 3604 | |
5f39d397 | 3605 | item = btrfs_item_nr(leaf, i); |
db94535d CM |
3606 | if (!leaf->map_token) { |
3607 | map_extent_buffer(leaf, (unsigned long)item, | |
3608 | sizeof(struct btrfs_item), | |
3609 | &leaf->map_token, &leaf->kaddr, | |
3610 | &leaf->map_start, &leaf->map_len, | |
3611 | KM_USER1); | |
3612 | } | |
3613 | ||
5f39d397 | 3614 | ioff = btrfs_item_offset(leaf, item); |
9c58309d | 3615 | btrfs_set_item_offset(leaf, item, ioff - total_data); |
0783fcfc | 3616 | } |
db94535d CM |
3617 | if (leaf->map_token) { |
3618 | unmap_extent_buffer(leaf, leaf->map_token, KM_USER1); | |
3619 | leaf->map_token = NULL; | |
3620 | } | |
be0e5c09 CM |
3621 | |
3622 | /* shift the items */ | |
9c58309d | 3623 | memmove_extent_buffer(leaf, btrfs_item_nr_offset(slot + nr), |
5f39d397 | 3624 | btrfs_item_nr_offset(slot), |
d6025579 | 3625 | (nritems - slot) * sizeof(struct btrfs_item)); |
be0e5c09 CM |
3626 | |
3627 | /* shift the data */ | |
5f39d397 | 3628 | memmove_extent_buffer(leaf, btrfs_leaf_data(leaf) + |
9c58309d | 3629 | data_end - total_data, btrfs_leaf_data(leaf) + |
d6025579 | 3630 | data_end, old_data - data_end); |
be0e5c09 CM |
3631 | data_end = old_data; |
3632 | } | |
5f39d397 | 3633 | |
62e2749e | 3634 | /* setup the item for the new data */ |
9c58309d CM |
3635 | for (i = 0; i < nr; i++) { |
3636 | btrfs_cpu_key_to_disk(&disk_key, cpu_key + i); | |
3637 | btrfs_set_item_key(leaf, &disk_key, slot + i); | |
3638 | item = btrfs_item_nr(leaf, slot + i); | |
3639 | btrfs_set_item_offset(leaf, item, data_end - data_size[i]); | |
3640 | data_end -= data_size[i]; | |
3641 | btrfs_set_item_size(leaf, item, data_size[i]); | |
3642 | } | |
44871b1b | 3643 | |
9c58309d | 3644 | btrfs_set_header_nritems(leaf, nritems + nr); |
aa5d6bed CM |
3645 | |
3646 | ret = 0; | |
5a01a2e3 | 3647 | if (slot == 0) { |
44871b1b | 3648 | struct btrfs_disk_key disk_key; |
5a01a2e3 | 3649 | btrfs_cpu_key_to_disk(&disk_key, cpu_key); |
e089f05c | 3650 | ret = fixup_low_keys(trans, root, path, &disk_key, 1); |
5a01a2e3 | 3651 | } |
b9473439 CM |
3652 | btrfs_unlock_up_safe(path, 1); |
3653 | btrfs_mark_buffer_dirty(leaf); | |
aa5d6bed | 3654 | |
5f39d397 CM |
3655 | if (btrfs_leaf_free_space(root, leaf) < 0) { |
3656 | btrfs_print_leaf(root, leaf); | |
be0e5c09 | 3657 | BUG(); |
5f39d397 | 3658 | } |
44871b1b CM |
3659 | return ret; |
3660 | } | |
3661 | ||
3662 | /* | |
3663 | * Given a key and some data, insert items into the tree. | |
3664 | * This does all the path init required, making room in the tree if needed. | |
3665 | */ | |
3666 | int btrfs_insert_empty_items(struct btrfs_trans_handle *trans, | |
3667 | struct btrfs_root *root, | |
3668 | struct btrfs_path *path, | |
3669 | struct btrfs_key *cpu_key, u32 *data_size, | |
3670 | int nr) | |
3671 | { | |
3672 | struct extent_buffer *leaf; | |
3673 | int ret = 0; | |
3674 | int slot; | |
3675 | int i; | |
3676 | u32 total_size = 0; | |
3677 | u32 total_data = 0; | |
3678 | ||
3679 | for (i = 0; i < nr; i++) | |
3680 | total_data += data_size[i]; | |
3681 | ||
3682 | total_size = total_data + (nr * sizeof(struct btrfs_item)); | |
3683 | ret = btrfs_search_slot(trans, root, cpu_key, path, total_size, 1); | |
3684 | if (ret == 0) | |
3685 | return -EEXIST; | |
3686 | if (ret < 0) | |
3687 | goto out; | |
3688 | ||
3689 | leaf = path->nodes[0]; | |
3690 | slot = path->slots[0]; | |
3691 | BUG_ON(slot < 0); | |
3692 | ||
3693 | ret = setup_items_for_insert(trans, root, path, cpu_key, data_size, | |
3694 | total_data, total_size, nr); | |
3695 | ||
ed2ff2cb | 3696 | out: |
62e2749e CM |
3697 | return ret; |
3698 | } | |
3699 | ||
3700 | /* | |
3701 | * Given a key and some data, insert an item into the tree. | |
3702 | * This does all the path init required, making room in the tree if needed. | |
3703 | */ | |
e089f05c CM |
3704 | int btrfs_insert_item(struct btrfs_trans_handle *trans, struct btrfs_root |
3705 | *root, struct btrfs_key *cpu_key, void *data, u32 | |
3706 | data_size) | |
62e2749e CM |
3707 | { |
3708 | int ret = 0; | |
2c90e5d6 | 3709 | struct btrfs_path *path; |
5f39d397 CM |
3710 | struct extent_buffer *leaf; |
3711 | unsigned long ptr; | |
62e2749e | 3712 | |
2c90e5d6 CM |
3713 | path = btrfs_alloc_path(); |
3714 | BUG_ON(!path); | |
2c90e5d6 | 3715 | ret = btrfs_insert_empty_item(trans, root, path, cpu_key, data_size); |
62e2749e | 3716 | if (!ret) { |
5f39d397 CM |
3717 | leaf = path->nodes[0]; |
3718 | ptr = btrfs_item_ptr_offset(leaf, path->slots[0]); | |
3719 | write_extent_buffer(leaf, data, ptr, data_size); | |
3720 | btrfs_mark_buffer_dirty(leaf); | |
62e2749e | 3721 | } |
2c90e5d6 | 3722 | btrfs_free_path(path); |
aa5d6bed | 3723 | return ret; |
be0e5c09 CM |
3724 | } |
3725 | ||
74123bd7 | 3726 | /* |
5de08d7d | 3727 | * delete the pointer from a given node. |
74123bd7 | 3728 | * |
d352ac68 CM |
3729 | * the tree should have been previously balanced so the deletion does not |
3730 | * empty a node. | |
74123bd7 | 3731 | */ |
e089f05c CM |
3732 | static int del_ptr(struct btrfs_trans_handle *trans, struct btrfs_root *root, |
3733 | struct btrfs_path *path, int level, int slot) | |
be0e5c09 | 3734 | { |
5f39d397 | 3735 | struct extent_buffer *parent = path->nodes[level]; |
7518a238 | 3736 | u32 nritems; |
aa5d6bed | 3737 | int ret = 0; |
bb803951 | 3738 | int wret; |
be0e5c09 | 3739 | |
5f39d397 | 3740 | nritems = btrfs_header_nritems(parent); |
d397712b | 3741 | if (slot != nritems - 1) { |
5f39d397 CM |
3742 | memmove_extent_buffer(parent, |
3743 | btrfs_node_key_ptr_offset(slot), | |
3744 | btrfs_node_key_ptr_offset(slot + 1), | |
d6025579 CM |
3745 | sizeof(struct btrfs_key_ptr) * |
3746 | (nritems - slot - 1)); | |
bb803951 | 3747 | } |
7518a238 | 3748 | nritems--; |
5f39d397 | 3749 | btrfs_set_header_nritems(parent, nritems); |
7518a238 | 3750 | if (nritems == 0 && parent == root->node) { |
5f39d397 | 3751 | BUG_ON(btrfs_header_level(root->node) != 1); |
bb803951 | 3752 | /* just turn the root into a leaf and break */ |
5f39d397 | 3753 | btrfs_set_header_level(root->node, 0); |
bb803951 | 3754 | } else if (slot == 0) { |
5f39d397 CM |
3755 | struct btrfs_disk_key disk_key; |
3756 | ||
3757 | btrfs_node_key(parent, &disk_key, 0); | |
3758 | wret = fixup_low_keys(trans, root, path, &disk_key, level + 1); | |
0f70abe2 CM |
3759 | if (wret) |
3760 | ret = wret; | |
be0e5c09 | 3761 | } |
d6025579 | 3762 | btrfs_mark_buffer_dirty(parent); |
aa5d6bed | 3763 | return ret; |
be0e5c09 CM |
3764 | } |
3765 | ||
323ac95b CM |
3766 | /* |
3767 | * a helper function to delete the leaf pointed to by path->slots[1] and | |
5d4f98a2 | 3768 | * path->nodes[1]. |
323ac95b CM |
3769 | * |
3770 | * This deletes the pointer in path->nodes[1] and frees the leaf | |
3771 | * block extent. zero is returned if it all worked out, < 0 otherwise. | |
3772 | * | |
3773 | * The path must have already been setup for deleting the leaf, including | |
3774 | * all the proper balancing. path->nodes[1] must be locked. | |
3775 | */ | |
5d4f98a2 YZ |
3776 | static noinline int btrfs_del_leaf(struct btrfs_trans_handle *trans, |
3777 | struct btrfs_root *root, | |
3778 | struct btrfs_path *path, | |
3779 | struct extent_buffer *leaf) | |
323ac95b CM |
3780 | { |
3781 | int ret; | |
323ac95b | 3782 | |
5d4f98a2 | 3783 | WARN_ON(btrfs_header_generation(leaf) != trans->transid); |
323ac95b CM |
3784 | ret = del_ptr(trans, root, path, 1, path->slots[1]); |
3785 | if (ret) | |
3786 | return ret; | |
3787 | ||
4d081c41 CM |
3788 | /* |
3789 | * btrfs_free_extent is expensive, we want to make sure we | |
3790 | * aren't holding any locks when we call it | |
3791 | */ | |
3792 | btrfs_unlock_up_safe(path, 0); | |
3793 | ||
86b9f2ec YZ |
3794 | ret = btrfs_free_tree_block(trans, root, leaf->start, leaf->len, |
3795 | 0, root->root_key.objectid, 0); | |
323ac95b CM |
3796 | return ret; |
3797 | } | |
74123bd7 CM |
3798 | /* |
3799 | * delete the item at the leaf level in path. If that empties | |
3800 | * the leaf, remove it from the tree | |
3801 | */ | |
85e21bac CM |
3802 | int btrfs_del_items(struct btrfs_trans_handle *trans, struct btrfs_root *root, |
3803 | struct btrfs_path *path, int slot, int nr) | |
be0e5c09 | 3804 | { |
5f39d397 CM |
3805 | struct extent_buffer *leaf; |
3806 | struct btrfs_item *item; | |
85e21bac CM |
3807 | int last_off; |
3808 | int dsize = 0; | |
aa5d6bed CM |
3809 | int ret = 0; |
3810 | int wret; | |
85e21bac | 3811 | int i; |
7518a238 | 3812 | u32 nritems; |
be0e5c09 | 3813 | |
5f39d397 | 3814 | leaf = path->nodes[0]; |
85e21bac CM |
3815 | last_off = btrfs_item_offset_nr(leaf, slot + nr - 1); |
3816 | ||
3817 | for (i = 0; i < nr; i++) | |
3818 | dsize += btrfs_item_size_nr(leaf, slot + i); | |
3819 | ||
5f39d397 | 3820 | nritems = btrfs_header_nritems(leaf); |
be0e5c09 | 3821 | |
85e21bac | 3822 | if (slot + nr != nritems) { |
123abc88 | 3823 | int data_end = leaf_data_end(root, leaf); |
5f39d397 CM |
3824 | |
3825 | memmove_extent_buffer(leaf, btrfs_leaf_data(leaf) + | |
d6025579 CM |
3826 | data_end + dsize, |
3827 | btrfs_leaf_data(leaf) + data_end, | |
85e21bac | 3828 | last_off - data_end); |
5f39d397 | 3829 | |
85e21bac | 3830 | for (i = slot + nr; i < nritems; i++) { |
5f39d397 | 3831 | u32 ioff; |
db94535d | 3832 | |
5f39d397 | 3833 | item = btrfs_item_nr(leaf, i); |
db94535d CM |
3834 | if (!leaf->map_token) { |
3835 | map_extent_buffer(leaf, (unsigned long)item, | |
3836 | sizeof(struct btrfs_item), | |
3837 | &leaf->map_token, &leaf->kaddr, | |
3838 | &leaf->map_start, &leaf->map_len, | |
3839 | KM_USER1); | |
3840 | } | |
5f39d397 CM |
3841 | ioff = btrfs_item_offset(leaf, item); |
3842 | btrfs_set_item_offset(leaf, item, ioff + dsize); | |
0783fcfc | 3843 | } |
db94535d CM |
3844 | |
3845 | if (leaf->map_token) { | |
3846 | unmap_extent_buffer(leaf, leaf->map_token, KM_USER1); | |
3847 | leaf->map_token = NULL; | |
3848 | } | |
3849 | ||
5f39d397 | 3850 | memmove_extent_buffer(leaf, btrfs_item_nr_offset(slot), |
85e21bac | 3851 | btrfs_item_nr_offset(slot + nr), |
d6025579 | 3852 | sizeof(struct btrfs_item) * |
85e21bac | 3853 | (nritems - slot - nr)); |
be0e5c09 | 3854 | } |
85e21bac CM |
3855 | btrfs_set_header_nritems(leaf, nritems - nr); |
3856 | nritems -= nr; | |
5f39d397 | 3857 | |
74123bd7 | 3858 | /* delete the leaf if we've emptied it */ |
7518a238 | 3859 | if (nritems == 0) { |
5f39d397 CM |
3860 | if (leaf == root->node) { |
3861 | btrfs_set_header_level(leaf, 0); | |
9a8dd150 | 3862 | } else { |
5d4f98a2 | 3863 | ret = btrfs_del_leaf(trans, root, path, leaf); |
323ac95b | 3864 | BUG_ON(ret); |
9a8dd150 | 3865 | } |
be0e5c09 | 3866 | } else { |
7518a238 | 3867 | int used = leaf_space_used(leaf, 0, nritems); |
aa5d6bed | 3868 | if (slot == 0) { |
5f39d397 CM |
3869 | struct btrfs_disk_key disk_key; |
3870 | ||
3871 | btrfs_item_key(leaf, &disk_key, 0); | |
e089f05c | 3872 | wret = fixup_low_keys(trans, root, path, |
5f39d397 | 3873 | &disk_key, 1); |
aa5d6bed CM |
3874 | if (wret) |
3875 | ret = wret; | |
3876 | } | |
aa5d6bed | 3877 | |
74123bd7 | 3878 | /* delete the leaf if it is mostly empty */ |
d717aa1d | 3879 | if (used < BTRFS_LEAF_DATA_SIZE(root) / 3) { |
be0e5c09 CM |
3880 | /* push_leaf_left fixes the path. |
3881 | * make sure the path still points to our leaf | |
3882 | * for possible call to del_ptr below | |
3883 | */ | |
4920c9ac | 3884 | slot = path->slots[1]; |
5f39d397 CM |
3885 | extent_buffer_get(leaf); |
3886 | ||
b9473439 | 3887 | btrfs_set_path_blocking(path); |
85e21bac | 3888 | wret = push_leaf_left(trans, root, path, 1, 1); |
54aa1f4d | 3889 | if (wret < 0 && wret != -ENOSPC) |
aa5d6bed | 3890 | ret = wret; |
5f39d397 CM |
3891 | |
3892 | if (path->nodes[0] == leaf && | |
3893 | btrfs_header_nritems(leaf)) { | |
85e21bac | 3894 | wret = push_leaf_right(trans, root, path, 1, 1); |
54aa1f4d | 3895 | if (wret < 0 && wret != -ENOSPC) |
aa5d6bed CM |
3896 | ret = wret; |
3897 | } | |
5f39d397 CM |
3898 | |
3899 | if (btrfs_header_nritems(leaf) == 0) { | |
323ac95b | 3900 | path->slots[1] = slot; |
5d4f98a2 | 3901 | ret = btrfs_del_leaf(trans, root, path, leaf); |
323ac95b | 3902 | BUG_ON(ret); |
5f39d397 | 3903 | free_extent_buffer(leaf); |
5de08d7d | 3904 | } else { |
925baedd CM |
3905 | /* if we're still in the path, make sure |
3906 | * we're dirty. Otherwise, one of the | |
3907 | * push_leaf functions must have already | |
3908 | * dirtied this buffer | |
3909 | */ | |
3910 | if (path->nodes[0] == leaf) | |
3911 | btrfs_mark_buffer_dirty(leaf); | |
5f39d397 | 3912 | free_extent_buffer(leaf); |
be0e5c09 | 3913 | } |
d5719762 | 3914 | } else { |
5f39d397 | 3915 | btrfs_mark_buffer_dirty(leaf); |
be0e5c09 CM |
3916 | } |
3917 | } | |
aa5d6bed | 3918 | return ret; |
be0e5c09 CM |
3919 | } |
3920 | ||
7bb86316 | 3921 | /* |
925baedd | 3922 | * search the tree again to find a leaf with lesser keys |
7bb86316 CM |
3923 | * returns 0 if it found something or 1 if there are no lesser leaves. |
3924 | * returns < 0 on io errors. | |
d352ac68 CM |
3925 | * |
3926 | * This may release the path, and so you may lose any locks held at the | |
3927 | * time you call it. | |
7bb86316 CM |
3928 | */ |
3929 | int btrfs_prev_leaf(struct btrfs_root *root, struct btrfs_path *path) | |
3930 | { | |
925baedd CM |
3931 | struct btrfs_key key; |
3932 | struct btrfs_disk_key found_key; | |
3933 | int ret; | |
7bb86316 | 3934 | |
925baedd | 3935 | btrfs_item_key_to_cpu(path->nodes[0], &key, 0); |
7bb86316 | 3936 | |
925baedd CM |
3937 | if (key.offset > 0) |
3938 | key.offset--; | |
3939 | else if (key.type > 0) | |
3940 | key.type--; | |
3941 | else if (key.objectid > 0) | |
3942 | key.objectid--; | |
3943 | else | |
3944 | return 1; | |
7bb86316 | 3945 | |
925baedd CM |
3946 | btrfs_release_path(root, path); |
3947 | ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); | |
3948 | if (ret < 0) | |
3949 | return ret; | |
3950 | btrfs_item_key(path->nodes[0], &found_key, 0); | |
3951 | ret = comp_keys(&found_key, &key); | |
3952 | if (ret < 0) | |
3953 | return 0; | |
3954 | return 1; | |
7bb86316 CM |
3955 | } |
3956 | ||
3f157a2f CM |
3957 | /* |
3958 | * A helper function to walk down the tree starting at min_key, and looking | |
3959 | * for nodes or leaves that are either in cache or have a minimum | |
d352ac68 | 3960 | * transaction id. This is used by the btree defrag code, and tree logging |
3f157a2f CM |
3961 | * |
3962 | * This does not cow, but it does stuff the starting key it finds back | |
3963 | * into min_key, so you can call btrfs_search_slot with cow=1 on the | |
3964 | * key and get a writable path. | |
3965 | * | |
3966 | * This does lock as it descends, and path->keep_locks should be set | |
3967 | * to 1 by the caller. | |
3968 | * | |
3969 | * This honors path->lowest_level to prevent descent past a given level | |
3970 | * of the tree. | |
3971 | * | |
d352ac68 CM |
3972 | * min_trans indicates the oldest transaction that you are interested |
3973 | * in walking through. Any nodes or leaves older than min_trans are | |
3974 | * skipped over (without reading them). | |
3975 | * | |
3f157a2f CM |
3976 | * returns zero if something useful was found, < 0 on error and 1 if there |
3977 | * was nothing in the tree that matched the search criteria. | |
3978 | */ | |
3979 | int btrfs_search_forward(struct btrfs_root *root, struct btrfs_key *min_key, | |
e02119d5 | 3980 | struct btrfs_key *max_key, |
3f157a2f CM |
3981 | struct btrfs_path *path, int cache_only, |
3982 | u64 min_trans) | |
3983 | { | |
3984 | struct extent_buffer *cur; | |
3985 | struct btrfs_key found_key; | |
3986 | int slot; | |
9652480b | 3987 | int sret; |
3f157a2f CM |
3988 | u32 nritems; |
3989 | int level; | |
3990 | int ret = 1; | |
3991 | ||
934d375b | 3992 | WARN_ON(!path->keep_locks); |
3f157a2f CM |
3993 | again: |
3994 | cur = btrfs_lock_root_node(root); | |
3995 | level = btrfs_header_level(cur); | |
e02119d5 | 3996 | WARN_ON(path->nodes[level]); |
3f157a2f CM |
3997 | path->nodes[level] = cur; |
3998 | path->locks[level] = 1; | |
3999 | ||
4000 | if (btrfs_header_generation(cur) < min_trans) { | |
4001 | ret = 1; | |
4002 | goto out; | |
4003 | } | |
d397712b | 4004 | while (1) { |
3f157a2f CM |
4005 | nritems = btrfs_header_nritems(cur); |
4006 | level = btrfs_header_level(cur); | |
9652480b | 4007 | sret = bin_search(cur, min_key, level, &slot); |
3f157a2f | 4008 | |
323ac95b CM |
4009 | /* at the lowest level, we're done, setup the path and exit */ |
4010 | if (level == path->lowest_level) { | |
e02119d5 CM |
4011 | if (slot >= nritems) |
4012 | goto find_next_key; | |
3f157a2f CM |
4013 | ret = 0; |
4014 | path->slots[level] = slot; | |
4015 | btrfs_item_key_to_cpu(cur, &found_key, slot); | |
4016 | goto out; | |
4017 | } | |
9652480b Y |
4018 | if (sret && slot > 0) |
4019 | slot--; | |
3f157a2f CM |
4020 | /* |
4021 | * check this node pointer against the cache_only and | |
4022 | * min_trans parameters. If it isn't in cache or is too | |
4023 | * old, skip to the next one. | |
4024 | */ | |
d397712b | 4025 | while (slot < nritems) { |
3f157a2f CM |
4026 | u64 blockptr; |
4027 | u64 gen; | |
4028 | struct extent_buffer *tmp; | |
e02119d5 CM |
4029 | struct btrfs_disk_key disk_key; |
4030 | ||
3f157a2f CM |
4031 | blockptr = btrfs_node_blockptr(cur, slot); |
4032 | gen = btrfs_node_ptr_generation(cur, slot); | |
4033 | if (gen < min_trans) { | |
4034 | slot++; | |
4035 | continue; | |
4036 | } | |
4037 | if (!cache_only) | |
4038 | break; | |
4039 | ||
e02119d5 CM |
4040 | if (max_key) { |
4041 | btrfs_node_key(cur, &disk_key, slot); | |
4042 | if (comp_keys(&disk_key, max_key) >= 0) { | |
4043 | ret = 1; | |
4044 | goto out; | |
4045 | } | |
4046 | } | |
4047 | ||
3f157a2f CM |
4048 | tmp = btrfs_find_tree_block(root, blockptr, |
4049 | btrfs_level_size(root, level - 1)); | |
4050 | ||
4051 | if (tmp && btrfs_buffer_uptodate(tmp, gen)) { | |
4052 | free_extent_buffer(tmp); | |
4053 | break; | |
4054 | } | |
4055 | if (tmp) | |
4056 | free_extent_buffer(tmp); | |
4057 | slot++; | |
4058 | } | |
e02119d5 | 4059 | find_next_key: |
3f157a2f CM |
4060 | /* |
4061 | * we didn't find a candidate key in this node, walk forward | |
4062 | * and find another one | |
4063 | */ | |
4064 | if (slot >= nritems) { | |
e02119d5 | 4065 | path->slots[level] = slot; |
b4ce94de | 4066 | btrfs_set_path_blocking(path); |
e02119d5 | 4067 | sret = btrfs_find_next_key(root, path, min_key, level, |
3f157a2f | 4068 | cache_only, min_trans); |
e02119d5 | 4069 | if (sret == 0) { |
3f157a2f CM |
4070 | btrfs_release_path(root, path); |
4071 | goto again; | |
4072 | } else { | |
4073 | goto out; | |
4074 | } | |
4075 | } | |
4076 | /* save our key for returning back */ | |
4077 | btrfs_node_key_to_cpu(cur, &found_key, slot); | |
4078 | path->slots[level] = slot; | |
4079 | if (level == path->lowest_level) { | |
4080 | ret = 0; | |
4081 | unlock_up(path, level, 1); | |
4082 | goto out; | |
4083 | } | |
b4ce94de | 4084 | btrfs_set_path_blocking(path); |
3f157a2f CM |
4085 | cur = read_node_slot(root, cur, slot); |
4086 | ||
4087 | btrfs_tree_lock(cur); | |
b4ce94de | 4088 | |
3f157a2f CM |
4089 | path->locks[level - 1] = 1; |
4090 | path->nodes[level - 1] = cur; | |
4091 | unlock_up(path, level, 1); | |
4008c04a | 4092 | btrfs_clear_path_blocking(path, NULL); |
3f157a2f CM |
4093 | } |
4094 | out: | |
4095 | if (ret == 0) | |
4096 | memcpy(min_key, &found_key, sizeof(found_key)); | |
b4ce94de | 4097 | btrfs_set_path_blocking(path); |
3f157a2f CM |
4098 | return ret; |
4099 | } | |
4100 | ||
4101 | /* | |
4102 | * this is similar to btrfs_next_leaf, but does not try to preserve | |
4103 | * and fixup the path. It looks for and returns the next key in the | |
4104 | * tree based on the current path and the cache_only and min_trans | |
4105 | * parameters. | |
4106 | * | |
4107 | * 0 is returned if another key is found, < 0 if there are any errors | |
4108 | * and 1 is returned if there are no higher keys in the tree | |
4109 | * | |
4110 | * path->keep_locks should be set to 1 on the search made before | |
4111 | * calling this function. | |
4112 | */ | |
e7a84565 | 4113 | int btrfs_find_next_key(struct btrfs_root *root, struct btrfs_path *path, |
33c66f43 | 4114 | struct btrfs_key *key, int level, |
3f157a2f | 4115 | int cache_only, u64 min_trans) |
e7a84565 | 4116 | { |
e7a84565 CM |
4117 | int slot; |
4118 | struct extent_buffer *c; | |
4119 | ||
934d375b | 4120 | WARN_ON(!path->keep_locks); |
d397712b | 4121 | while (level < BTRFS_MAX_LEVEL) { |
e7a84565 CM |
4122 | if (!path->nodes[level]) |
4123 | return 1; | |
4124 | ||
4125 | slot = path->slots[level] + 1; | |
4126 | c = path->nodes[level]; | |
3f157a2f | 4127 | next: |
e7a84565 | 4128 | if (slot >= btrfs_header_nritems(c)) { |
33c66f43 YZ |
4129 | int ret; |
4130 | int orig_lowest; | |
4131 | struct btrfs_key cur_key; | |
4132 | if (level + 1 >= BTRFS_MAX_LEVEL || | |
4133 | !path->nodes[level + 1]) | |
e7a84565 | 4134 | return 1; |
33c66f43 YZ |
4135 | |
4136 | if (path->locks[level + 1]) { | |
4137 | level++; | |
4138 | continue; | |
4139 | } | |
4140 | ||
4141 | slot = btrfs_header_nritems(c) - 1; | |
4142 | if (level == 0) | |
4143 | btrfs_item_key_to_cpu(c, &cur_key, slot); | |
4144 | else | |
4145 | btrfs_node_key_to_cpu(c, &cur_key, slot); | |
4146 | ||
4147 | orig_lowest = path->lowest_level; | |
4148 | btrfs_release_path(root, path); | |
4149 | path->lowest_level = level; | |
4150 | ret = btrfs_search_slot(NULL, root, &cur_key, path, | |
4151 | 0, 0); | |
4152 | path->lowest_level = orig_lowest; | |
4153 | if (ret < 0) | |
4154 | return ret; | |
4155 | ||
4156 | c = path->nodes[level]; | |
4157 | slot = path->slots[level]; | |
4158 | if (ret == 0) | |
4159 | slot++; | |
4160 | goto next; | |
e7a84565 | 4161 | } |
33c66f43 | 4162 | |
e7a84565 CM |
4163 | if (level == 0) |
4164 | btrfs_item_key_to_cpu(c, key, slot); | |
3f157a2f CM |
4165 | else { |
4166 | u64 blockptr = btrfs_node_blockptr(c, slot); | |
4167 | u64 gen = btrfs_node_ptr_generation(c, slot); | |
4168 | ||
4169 | if (cache_only) { | |
4170 | struct extent_buffer *cur; | |
4171 | cur = btrfs_find_tree_block(root, blockptr, | |
4172 | btrfs_level_size(root, level - 1)); | |
4173 | if (!cur || !btrfs_buffer_uptodate(cur, gen)) { | |
4174 | slot++; | |
4175 | if (cur) | |
4176 | free_extent_buffer(cur); | |
4177 | goto next; | |
4178 | } | |
4179 | free_extent_buffer(cur); | |
4180 | } | |
4181 | if (gen < min_trans) { | |
4182 | slot++; | |
4183 | goto next; | |
4184 | } | |
e7a84565 | 4185 | btrfs_node_key_to_cpu(c, key, slot); |
3f157a2f | 4186 | } |
e7a84565 CM |
4187 | return 0; |
4188 | } | |
4189 | return 1; | |
4190 | } | |
4191 | ||
97571fd0 | 4192 | /* |
925baedd | 4193 | * search the tree again to find a leaf with greater keys |
0f70abe2 CM |
4194 | * returns 0 if it found something or 1 if there are no greater leaves. |
4195 | * returns < 0 on io errors. | |
97571fd0 | 4196 | */ |
234b63a0 | 4197 | int btrfs_next_leaf(struct btrfs_root *root, struct btrfs_path *path) |
d97e63b6 CM |
4198 | { |
4199 | int slot; | |
8e73f275 | 4200 | int level; |
5f39d397 | 4201 | struct extent_buffer *c; |
8e73f275 | 4202 | struct extent_buffer *next; |
925baedd CM |
4203 | struct btrfs_key key; |
4204 | u32 nritems; | |
4205 | int ret; | |
8e73f275 CM |
4206 | int old_spinning = path->leave_spinning; |
4207 | int force_blocking = 0; | |
925baedd CM |
4208 | |
4209 | nritems = btrfs_header_nritems(path->nodes[0]); | |
d397712b | 4210 | if (nritems == 0) |
925baedd | 4211 | return 1; |
925baedd | 4212 | |
8e73f275 CM |
4213 | /* |
4214 | * we take the blocks in an order that upsets lockdep. Using | |
4215 | * blocking mode is the only way around it. | |
4216 | */ | |
4217 | #ifdef CONFIG_DEBUG_LOCK_ALLOC | |
4218 | force_blocking = 1; | |
4219 | #endif | |
925baedd | 4220 | |
8e73f275 CM |
4221 | btrfs_item_key_to_cpu(path->nodes[0], &key, nritems - 1); |
4222 | again: | |
4223 | level = 1; | |
4224 | next = NULL; | |
925baedd | 4225 | btrfs_release_path(root, path); |
8e73f275 | 4226 | |
a2135011 | 4227 | path->keep_locks = 1; |
8e73f275 CM |
4228 | |
4229 | if (!force_blocking) | |
4230 | path->leave_spinning = 1; | |
4231 | ||
925baedd CM |
4232 | ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); |
4233 | path->keep_locks = 0; | |
4234 | ||
4235 | if (ret < 0) | |
4236 | return ret; | |
4237 | ||
a2135011 | 4238 | nritems = btrfs_header_nritems(path->nodes[0]); |
168fd7d2 CM |
4239 | /* |
4240 | * by releasing the path above we dropped all our locks. A balance | |
4241 | * could have added more items next to the key that used to be | |
4242 | * at the very end of the block. So, check again here and | |
4243 | * advance the path if there are now more items available. | |
4244 | */ | |
a2135011 | 4245 | if (nritems > 0 && path->slots[0] < nritems - 1) { |
e457afec YZ |
4246 | if (ret == 0) |
4247 | path->slots[0]++; | |
8e73f275 | 4248 | ret = 0; |
925baedd CM |
4249 | goto done; |
4250 | } | |
d97e63b6 | 4251 | |
d397712b | 4252 | while (level < BTRFS_MAX_LEVEL) { |
8e73f275 CM |
4253 | if (!path->nodes[level]) { |
4254 | ret = 1; | |
4255 | goto done; | |
4256 | } | |
5f39d397 | 4257 | |
d97e63b6 CM |
4258 | slot = path->slots[level] + 1; |
4259 | c = path->nodes[level]; | |
5f39d397 | 4260 | if (slot >= btrfs_header_nritems(c)) { |
d97e63b6 | 4261 | level++; |
8e73f275 CM |
4262 | if (level == BTRFS_MAX_LEVEL) { |
4263 | ret = 1; | |
4264 | goto done; | |
4265 | } | |
d97e63b6 CM |
4266 | continue; |
4267 | } | |
5f39d397 | 4268 | |
925baedd CM |
4269 | if (next) { |
4270 | btrfs_tree_unlock(next); | |
5f39d397 | 4271 | free_extent_buffer(next); |
925baedd | 4272 | } |
5f39d397 | 4273 | |
8e73f275 CM |
4274 | next = c; |
4275 | ret = read_block_for_search(NULL, root, path, &next, level, | |
4276 | slot, &key); | |
4277 | if (ret == -EAGAIN) | |
4278 | goto again; | |
5f39d397 | 4279 | |
76a05b35 CM |
4280 | if (ret < 0) { |
4281 | btrfs_release_path(root, path); | |
4282 | goto done; | |
4283 | } | |
4284 | ||
5cd57b2c | 4285 | if (!path->skip_locking) { |
8e73f275 CM |
4286 | ret = btrfs_try_spin_lock(next); |
4287 | if (!ret) { | |
4288 | btrfs_set_path_blocking(path); | |
4289 | btrfs_tree_lock(next); | |
4290 | if (!force_blocking) | |
4291 | btrfs_clear_path_blocking(path, next); | |
4292 | } | |
4293 | if (force_blocking) | |
4294 | btrfs_set_lock_blocking(next); | |
5cd57b2c | 4295 | } |
d97e63b6 CM |
4296 | break; |
4297 | } | |
4298 | path->slots[level] = slot; | |
d397712b | 4299 | while (1) { |
d97e63b6 CM |
4300 | level--; |
4301 | c = path->nodes[level]; | |
925baedd CM |
4302 | if (path->locks[level]) |
4303 | btrfs_tree_unlock(c); | |
8e73f275 | 4304 | |
5f39d397 | 4305 | free_extent_buffer(c); |
d97e63b6 CM |
4306 | path->nodes[level] = next; |
4307 | path->slots[level] = 0; | |
a74a4b97 CM |
4308 | if (!path->skip_locking) |
4309 | path->locks[level] = 1; | |
8e73f275 | 4310 | |
d97e63b6 CM |
4311 | if (!level) |
4312 | break; | |
b4ce94de | 4313 | |
8e73f275 CM |
4314 | ret = read_block_for_search(NULL, root, path, &next, level, |
4315 | 0, &key); | |
4316 | if (ret == -EAGAIN) | |
4317 | goto again; | |
4318 | ||
76a05b35 CM |
4319 | if (ret < 0) { |
4320 | btrfs_release_path(root, path); | |
4321 | goto done; | |
4322 | } | |
4323 | ||
5cd57b2c | 4324 | if (!path->skip_locking) { |
b9447ef8 | 4325 | btrfs_assert_tree_locked(path->nodes[level]); |
8e73f275 CM |
4326 | ret = btrfs_try_spin_lock(next); |
4327 | if (!ret) { | |
4328 | btrfs_set_path_blocking(path); | |
4329 | btrfs_tree_lock(next); | |
4330 | if (!force_blocking) | |
4331 | btrfs_clear_path_blocking(path, next); | |
4332 | } | |
4333 | if (force_blocking) | |
4334 | btrfs_set_lock_blocking(next); | |
5cd57b2c | 4335 | } |
d97e63b6 | 4336 | } |
8e73f275 | 4337 | ret = 0; |
925baedd CM |
4338 | done: |
4339 | unlock_up(path, 0, 1); | |
8e73f275 CM |
4340 | path->leave_spinning = old_spinning; |
4341 | if (!old_spinning) | |
4342 | btrfs_set_path_blocking(path); | |
4343 | ||
4344 | return ret; | |
d97e63b6 | 4345 | } |
0b86a832 | 4346 | |
3f157a2f CM |
4347 | /* |
4348 | * this uses btrfs_prev_leaf to walk backwards in the tree, and keeps | |
4349 | * searching until it gets past min_objectid or finds an item of 'type' | |
4350 | * | |
4351 | * returns 0 if something is found, 1 if nothing was found and < 0 on error | |
4352 | */ | |
0b86a832 CM |
4353 | int btrfs_previous_item(struct btrfs_root *root, |
4354 | struct btrfs_path *path, u64 min_objectid, | |
4355 | int type) | |
4356 | { | |
4357 | struct btrfs_key found_key; | |
4358 | struct extent_buffer *leaf; | |
e02119d5 | 4359 | u32 nritems; |
0b86a832 CM |
4360 | int ret; |
4361 | ||
d397712b | 4362 | while (1) { |
0b86a832 | 4363 | if (path->slots[0] == 0) { |
b4ce94de | 4364 | btrfs_set_path_blocking(path); |
0b86a832 CM |
4365 | ret = btrfs_prev_leaf(root, path); |
4366 | if (ret != 0) | |
4367 | return ret; | |
4368 | } else { | |
4369 | path->slots[0]--; | |
4370 | } | |
4371 | leaf = path->nodes[0]; | |
e02119d5 CM |
4372 | nritems = btrfs_header_nritems(leaf); |
4373 | if (nritems == 0) | |
4374 | return 1; | |
4375 | if (path->slots[0] == nritems) | |
4376 | path->slots[0]--; | |
4377 | ||
0b86a832 | 4378 | btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); |
e02119d5 CM |
4379 | if (found_key.objectid < min_objectid) |
4380 | break; | |
0a4eefbb YZ |
4381 | if (found_key.type == type) |
4382 | return 0; | |
e02119d5 CM |
4383 | if (found_key.objectid == min_objectid && |
4384 | found_key.type < type) | |
4385 | break; | |
0b86a832 CM |
4386 | } |
4387 | return 1; | |
4388 | } |